Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/24/13
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
736 PM MDT SUN JUN 23 2013
.UPDATE...SHORT WAVE TROUGH MOVING ACROSS THE REGION IS TRIGGERING
THUNDERSTORMS OVER CENTRAL AND EASTERN COLORADO. BEST INSTABILITY
REMAINS OVER FAR EASTERN COLORADO WHERE CAPES ARE AROUND 1000 J/KG.
APPEARS THE BEST CHANCE FOR SEVERE STORMS WILL BE ACROSS SOUTHERN
WASHINGTON...ELBERT AND LINCOLN COUNTIES. THE HRRR SHOWS CONVECTION
OVER FAR NORTHEAST COLORADO THROUGH 09Z.
FARTHER WEST...ISOLATED TO SCATTERED STORMS CONTINUE TO MOVE ACROSS
THE MOUNTAINS AND FRONT RANGE. THESE STORMS ARE WEAKER AND ARE ONLY
EXPECTED TO PRODUCE MODERATE TO BRIEF HEAVY RAIN...SMALL HAIL AND
GUSTY WINDS. THE HRRR SHOWS ACTIVITY LINGERING UNTIL 09Z OVER WELD
COUNTY. WILL ADJUST POPS TO LAST THROUGH 09Z...THOUGH EXPECT MOST OF
THE ACTIVITY TO END BY 06Z.
&&
.AVIATION...THUNDERSTORM ACTIVITY WILL CONTINUE IN THE DENVER AREA
THROUGH AT LEAST 03Z. ISOLATED THUNDERSTORMS WILL REMAIN POSSIBLE
THROUGH 09Z...THOUGH MOST OF THE ACTIVITY WILL END MUCH SOONER AND
CLOSER TO 03Z. WINDS WILL REMAIN ERRATIC THROUGH 03Z DUE TO OUTFLOW
WINDS FROM THUNDERSTORMS. EVENTUALLY EXPECT WINDS TO BE SOUTHEAST
AND THEN TURN SOUTH-SOUTHWEST AFTER 06Z. MONDAY WILL BE MUCH DRIER
WITH SOUTHWEST WINDS PREVAILING.
&&
.PREV DISCUSSION... /ISSUED 305 PM MDT SUN JUN 23 2013/
SHORT TERM...SHORT WAVE DISTURBANCE CONTINUES TO PROGRESS
NORTHEASTWARD OVER UTAH AND SOUTHWEST COLORADO AT THIS HOUR. AT
ITS CURRENT SPEED SHOULD SEE ITS AXIS PASSING OVER THE NORTH
CENTRAL MTNS BY 00Z TODAY AND OVER THE FAR NERN PLAINS OF
COLORADO BY 06Z TONIGHT. STRONG MID-LEVEL DESTABLIZATION IN WARM
SECTOR OUT AHEAD OF THE S/W WILL COUPLE WITH SURFACE DEW POINTS IN
THE 25-35 DEG RANGE TO PRODUCE WEAK PULSE-TYPE T-STORMS ALONG THE
CONTINENTAL DIVIDE AND OVER THE FOOTHILLS DURING THE NEXT FEW
HOURS. ONCE ON THE PLAINS...STORM DEVELOPMENT SHOULD BECOME MORE
ORGANIZED...WITH STORMS FORMING IN THE VICINITY OF THE DENVER
CYCLONE AND ALONG THE CONVERGENCE ZONE SOUTH OF THE LOW.
SOUTHEASTERLY LOW-LEVEL FLOW ON THE PLAINS HAS SUPPRESSED DEW
POINTS SOME IN THE PAST FEW HOURS...HOWEVER INTEGRATED
PRECIPITABLE WATER VALUES HAVE CONTINUED TO CREEP UP THRU THE DAY
TO AROUND 0.65 INCH AT DEN. FIRST WAVE OF LOW-TOP CONVECTION
MOVING OFF THE FOOTHILLS AT THIS TIME WILL LIKELY PRODUCE OUTFLOW
BOUNDARIES THAT STRONGER STORMS WILL LIKELY FORM ALONG LATER THIS
AFTERNOON. SFC DEW POINTS IN THE 45-55 DEG F RANGE COMBINED WITH
TEMPERATURES IN THE LOW/MID 80S AND VERY STEEP MID-LEVEL LAPSE
RATES...AOA 8C/KM IN THE 700-500MB LAYER...WILL SUPPORT MEAN LAYER
CAPE VALUES FROM 1300-2200 J/KG ON THE PLAINS BY 00Z/MONDAY.
15-20KT E-SELY LOW- LEVEL WINDS OVERLAYED BY 30KT MID-LEVEL
W-SWLYS WILL ALSO GENERATE SUFFICIENT MEAN LAYER SHEAR FOR
ISOLATED SUPERCELLS ON THE PLAINS...CAPABLE OF LARGE
HAIL...DAMAGING WIND GUSTS AND PERHAPS A TORNADO OR TWO. AREAS TO
THE EAST AND NORTHEAST OF DENVER IN THE BEST POSITION TO SEE THIS
OCCURRING. STORMS IN THE DEEPER MOISTURE ACROSS THE NORTHEAST
CORNER COULD POTENTIALLY PRODUCE 1 TO 1.5 INCHES OF RAIN IN A
SHORT PERIOD OF TIME THIS EVENING. THE STORM PREDICTION CENTER
CURRENTLY HAS NORTHEAST COLORADO IN A SLIGHT RISK FOR SEVERE HAIL
AND WIND...WITH A BULLSEYE NEAR THE NORTHEAST CORNER. STORMS THIS
EVENING MOVE EAST-NORTHEAST WITH THE PASSING SHORTWAVE TROUGH WITH
THE BULK OF THIS ACTIVITY EXITING THE STATE BY AROUND
06Z/MIDNIGHT. TEMPERATURES TONIGHT ABOUT THE SAME AS LAST NIGHT
UNDER CLEARING SKIES AFTER MIDNIGHT.
ON MONDAY...THE FORECAST AREA COMES UNDER THE INFLUENCE OF STRONG
MID-LEVEL SUBSIDENCE AND A MUCH DRIER AIRMASS WITH A VERY WARM
SOUTHWEST FLOW ALOFT. STRONG SOLAR HEATING WILL IN TURN PRODUCE
STEEP BOUNDARY LAYER LAPSE RATES BY AFTERNOON. SOUTH-SOUTHWEST
SFC FLOW WILL PRETTY MUCH SCOUR OUT MUCH OF THE LOW-LEVEL
MOISTURE NOW COVERING THE PLAINS. SO THE CHANCE FOR ANY CONVECTION/
T-STORMS APPEARS MINIMAL AT THIS TIME. CONCERNS TURN TO WILDLAND
FIRE...AND ITS POTENTIAL FOR GROWTH. WILL BE ISSUING A FIREWEATHER
WATCH FOR SOUTH PARK ZONE 214...MIDDLE PARK ZONE 213 AND THE
PALMER DIVIDE ZONE 241 BASED ON LOW RH VALUES AND GUSTY SOUTHWEST
WINDS. THIS WATCH WILL RUN FROM 1 PM MDT TO 8 PM MDT MONDAY.
FINALLY TEMPERATURES ON MONDAY AS MUCH AS 10-12F WARMER THAN
TODAY.
LONG TERM...MODELS SHOW THE SOUTHWESTERLY FLOW ALOFT MONDAY NIGHT
TO BECOME ZONAL BY TUESDAY AS A FLAT UPPER RIDGE SOUTH OF COLORADO
MOVES THIS WAY. THE UPPER RIDGE AXIS BUILDS NORTHWARD TO THE WEST
OF THE CWA TUESDAY NIGHT THROUGH WEDNESDAY NIGHT BRINGING
NORTHWESTERLY FLOW ALOFT TO THE FORECAST AREA. THE SYNOPTIC SCALE
ENERGY IS PROGGED TO BE BENIGN MONDAY NIGHT...THEN WEAK DOWNWARD
QG VERTICAL VELOCITY IS PROGGED TUESDAY THROUGH WEDNESDAY. THE
BOUNDARY LAYER FLOW IS DOMINATED BY DOWNSLOPING TUESDAY...THEN
SOUTHEASTERLIES WEDNESDAY. FOR MOISTURE...MOST OF THE MODELS SHOW
SOME IN THE MID AND UPPER LEVELS MOST OF THE PERIOD...HOWEVER
BOUNDARY LAYER DEW POINTS ARE MAINLY IN THE LOWER 20S TO UPPER 30S
F RANGE ALL FIVE PERIODS. THE ONE EXCEPTION BEING THE FAR
NORTHEAST CORNER MONDAY EVENING...WHERE PROGGED VALUES GET INTO
THE 40S F. ALSO...LATER ON WEDNESDAY THEY COME UP A BIT WITH THE
SOUTHEASTERLY FLOW. THERE IS PRACTICALLY NO CAPE PROGGED OVER THE
CWA ALL FIVE PERIODS...JUST A TAD OVER THE MOUNTAINS AND FOOTHILLS
LATE DAY WEDNESDAY ON THE NAM ONLY. THERE IS NO MEASURABLE
RAINFALL ON ANY OF THE MODEL`S QPF FIELDS ALL FIVE PERIODS. THERE
IS AN OVERWHELMING MID LEVEL CAP OVER THE CWA ACCORDING TO THE
LAPSE RATES FIELDS ALL THE PERIODS. NO POPS ANYWHERE. CONCERNING
FIRE WEATHER ISSUES...WIND SPEEDS ARE RELATIVELY LOW MONDAY NIGHT
INTO WEDNESDAY MORNING. WEDNESDAY AFTERNOON...THE SOUTHEASTERLIES
OVER THE EASTERN HALF OF THE PLAINS COME UP TO NEAR 20 KNOTS.
SOMETHING TO WATCH. FOR TEMPERATURES...TUESDAY`S HIGHS LOOK CLOSE
TO MONDAY`S. WEDNESDAY`S ARE PROGGED UP 1-2 C FROM TUESDAY`S. FOR
THE LATER DAYS...THURSDAY THROUGH SUNDAY...MODELS CONTINUE TO SHOW
AN UPPER RIDGE RIGHT OVER OR PARTIALLY OVER COLORADO ALL FOUR
DAYS. THE RIDGE AXIS IS STILL INDICATED WEST OF THE CWA WITH WEAK
NORTHWESTERLY FLOW ALOFT FOR US. YESTERDAY`S 12Z MODEL RUNS
INDICATED SOME COOLER AIR OVER THE PLAINS FOR FRIDAY AND
SATURDAY. TODAY`S 12Z RUNS INDICATE ONLY A SLIGHTLY COOLER AIR
MASS JUST ON FRIDAY NOW. MOISTURE LOOKS A LITTLE BETTER WITH THE
LATEST RUNS...SO WILL GO WITH "SLIGHT CHANCE"S MOST LATE DAY
PERIODS...MORE SO FOR THE MOUNTAINS AND FOOTHILLS. TEMPERATURES
STAY ABOVE ALL FOUR DAYS.
AVIATION...LOW-TOP CONVECTION NOW MOVING OVER THE DENVER METRO
AREA. COULD SEE WIND GUSTS TO 40 MPH PRODUCED THIS FIRST WAVE OF
MOSTLY DRY CLOUD CELLS. MEANWHILE A DENVER CYCLONE WILL CONTINUE
TO FORM JUST TO THE NORTHEAST OF DENVER. WINDS ACROSS SOUTHERN
PORTIONS OF THE DENVER METRO AREA SHOULD REMAIN SOUTHEASTERLY FOR
THE NEXT FEW HOURS. WHILE WINDS OVER NORTHERN PORTIONS OF THE
METRO AREA WILL TURN NORTH-NORTHEASTERLY. A CONVERGENCE BOUNDARY
SETTING UP OVER THE SOUTH METRO AREA WILL ACT AS A FOCUS FOR
STORM FORMATION IN THE NEXT 1-2 HOURS. STORMS IN THE DENVER METRO
AREA...ESPLY SOUTHERN AND EASTERN PORTIONS...MAY GO SEVERE
BETWEEN 4 PM AND 7 PM MDT. HAIL AND DAMAGING WIND MAIN THREAT.
TERMINAL FORECASTS ALREADY HAVE A TEMPO FOR -TSRA AND STG WIND
GUSTS AFTER 22Z TODAY. OVERNIGHT...SKIES CLEAR WITH DRIER AIR
MOVING DOWN OFF THE FRONT RANGE AND PALMER DIVIDE. ON MONDAY...VFR
CONDITIONS WILL PREVAIL WITH SOUTH-SOUTHWEST WINDS OF 5-12 KTS
FOR MOST OF THE DAY.
FIRE WEATHER...FIRE WEATHER WATCH 1 PM TO 8 PM MDT ON MONDAY FOR
COZ213-214-241. LOW RELATIVE HUMIDITIES AND GUSTY SOUTHWEST WINDS
TO 30 MPH WILL BE POSSIBLE IN THE AFTERNOON AND EARLY EVENING.
HYDROLOGY...STRONG SLOW MOVING T-STORMS OVER THE NORTHEAST
PLAINS THIS EVENING COULD DEPOSIT 1 TO 1.5 INCHES OF RAIN IN A
SHORT PERIOD OF TIME. STORMS ELSEWHERE LATE THIS AFTERNOON AND
EVENING ARE EXPECTED TO PRODUCE NOT MUCH MORE THAN A QUARTER OF
RAIN. DRY WASHES AND ARROYOS ON THE PLAINS MAY PARTIALLY FILL
WITH FAST MOVING RUNOFF FORM THESE HEAVY SHOWERS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING
FOR COZ213-214-241.
&&
$$
SHORT TERM...BAKER
LONG TERM....RJK
AVIATION...MEIER
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
323 PM MDT SAT JUN 22 2013
.SHORT TERM...UPPER LEVEL SHORTWAVE TROUGH NOW PASSING OVER THE
NORTHERN ROCKIES WITH SOUTHWEST FLOW ALOFT OVER COLORADO.
FURTHERMORE A SURFACE TROUGH EXTENDS NORTHWARD ALONG THE FRONT
RANGE FROM A SURFACE LOW IN SOUTHEAST COLORADO. EAST OF THE TROUGH
SFC DEWPOINTS IN THE MID TO UPPER 50S. WESTERN PORTIONS OF THE
DENVER METRO AREA AND FOOTHILLS WEST OF THIS SFC TROUGH DEWPOINTS
IN THE UPPER 30S AND 40S. ON THE PLAINS EVEN WITH THE HIGHER
DEWPOINTS...BOUNDARY LAYER GENERALLY REMAINS CAPPED WITH LOW CIN
VALUES BASED ON LAPS AND RAP MODEL...PARTICULARLY IN THE FAR
NORTHEAST CORNER WHERE LOW CLOUDS FROM EARLIER TODAY HAVE BEEN
RELUCTANT TO BURN AWAY. ISOLATED CONVECTION DEVELOPING OVER
NORTHERN AND CENTRAL PORTIONS OF THE FRONT RANGE NOT PRODUCING
MUCH PRECIP YET AS PER RADAR...BUT WITH THE DRY SUB-CLOUD
ENVIRONMENT...POTENTIAL FOR STRONG/GUSTY MICROBURST WINDS PRETTY
HIGH. IT NOW APPEARS THAT STORM DEVELOPMENT ON THE PLAINS WILL
BEGIN ALONG THE PALMER DIVIDE AND ALONG A CONVERGENCE BOUNDARY
STRADDLING THE DENVER METRO AREA WHERE THE CAP AND BROKEN. THESE
STORMS SHOULD THEN TRACK NORTHEAST INTO DEEPER MOISTURE/GREATER
CAPES WHERE A FEW MAY BECOME SEVERE. AT THIS TIME SHEAR PROFILE
LOOKS MARGINAL FOR TORNADOES. BIGGEST THREAT FROM ISOLATED/WIDELY
SCATTERED MESOS WILL BE LARGE HAIL AND DAMAGING OUTFLOW WINDS...
AND PROBABLY NOT UNTIL AFTER 23Z THIS AFTERNOON. BELIEVE THE
CHANCE FOR SEVERE WEATHER WILL INCREASE OVER THE FAR NORTHEAST
CORNER OF THE STATE EARLY THIS EVENING WITH THE PASSAGE OF A WEAK
UPPER AIR DISTURBANCE VISIBLE ON WATER VAPOR IMAGERY NOW OVER WRN
WY/EXTREME NWRN CO. HAIL AT LEAST UP TO 2 INCHES AND WIND GUSTS TO
AT LEAST 60 MPH A POSSIBILITY.
OVERNIGHT...STORMS IN THE NORTHEAST SHOULD EITHER DISSIPATE OR
MOVE EAST OF THE STATE...LEAVING BEHIND AMPLE LOW LEVEL MOISTURE
IN THE FORM OF A THICK BLANKET OF STRATUS/STRATO-CUMULUS SIMILAR
TO WHAT WE SAW THIS MORNING. DURING THE DAY TOMORROW SOUTHWEST
FLOW ALOFT RESUMES BUT WITH A PRETTY VIGOROUS PERTABATION EMBEDDED
IN THIS FLOW. MODELS SHOW THIS FEATURE LIFTING NORTHEAST ACROSS
THE FORECAST AREA DURING THE AFTERNOON. MEANWHILE COUPLED
CIRCULATION AROUND A SFC LOW IN SE COLORADO AND A STRONG SFC HIGH
IN THE BLACK HILLS AREA WILL HELP TO FUNNEL LOW LEVEL MOISTURE
INTO NORTHEAST COLORADO ON EAST-SOUTHEASTERLY WINDS. SUCH A BNDRY
LAYER FLOW OFTEN GENERATES A DENVER CYCLE AS THE NAM INDICATES.
THIS WOULD POTENTIALLY INCREASE THE RISK OF T-STORMS ALONG AND
EAST OF THE FRONT RANGE AND PERHAPS A THREAT OF HAIL. WITH PW AND
THETA-E VALUES ON THE RISE TOMORROW...LOCALLY HEAVY RAINFALL ALSO
POSSIBLE SOMEWHERE ON THE PLAINS. COOLING ALOFT COUPLED WITH
INCREASED MOISTURE/IE...CLOUD COVER/MEANS LOWER TEMPERATURES. MAX
TEMPERATURES TOMORROW NEAR AVERAGE FOR THE DATE. FOR ALL OF THE
SAME REASONS...RED FLAG WATCH/WARNING NOT NECESSARY.
.LONG TERM...SOUTHWESTERLY FLOW ALOFT IS PROGGED FOR SUNDAY
NIGHT...THEN ZONAL FLOW MOVES IN AND CONTINUES THROUGH TUESDAY
NIGHT. SPEEDS ARE IN THE 30 TO 45 KNOT RANGE AT JET LEVEL ALL
FIVE PERIODS. BENIGN SYNOPTIC SCALE ENERGY IS PROGGED THROUGH THE
PERIODS. THE BOUNDARY LAYER FLOW IS PROGGED TO BE EASTERLY UP INTO
THE FOOTHILLS SUNDAY EVENING. BY MONDAY AFTERNOON...SOUTHWESTERLY
LOW LEVEL WINDS RETURN WITH PROGGED SPEEDS OVER THE SOUTH-CENTRAL
AND EASTERN CWA GETTING AROUND 20 KNOTS. FOR MOISTURE...THERE IS
SOME OVER THE EASTERN THREE-QUARTERS OF THE CWA SUNDAY EVENING.
MODELS ALSO SHOW A STRATUS DECK OVER MUCH OF THE PLAINS LATER
SUNDAY NIGHT INTO MONDAY MORNING. THERE IS LESS MOISTURE AROUND
LATE DAY MONDAY...THEN EVEN LESS LATE DAY TUESDAY. SUNDAY NIGHT`S
DEW POINT READINGS ARE PROGGED IN THE MID 40S TO UPPER 50S F FOR
MOST OF THE PLAINS. BY MONDAY LATE DAY...ONLY THE FAR NORTHEASTERN
BORDER HANGS ON TO 40S TO LOWER 50S F...THE REST OF THE PLAINS ARE
IN THE DRY TEENS TO LOWER 30S F. ALL OF THE CWA IS PROGGED TO HAVE
20S TO MID 30S F ON TUESDAY. THERE IS CAPE OVER THE PLAINS AND
MOST OF THE FOOTHILLS SUNDAY EVENING...WITH VALUES IN THE
1000-2000 J/KG RANGE OVER THE EASTERN HALF OF THE PLAINS. THE CAPE
IS PUSHED TO THE FAR NORTHEAST CORNER FOR LATE DAY MONDAY...THEN
NOTHING FOR LATE DAY TUESDAY. THE QPF FIELDS HAVE QUITE A BIT OF
MEASURABLE RAINFALL OVER THE EASTERN HALF OF THE PLAINS SUNDAY
EVENING. THEN THERE IS A TAD PROGGED OVER THE EASTERN BORDER LATE
MONDAY ON THE GFS...THEN NOTHING ANY WHERE ON TUESDAY. FOR
POPS...WILL GO WITH 10-30%S SUNDAY EVENING FROM THE DIVIDE THROUGH
THE EASTERN BORDER. HIGHEST OVER THE EAST. FOR LATE DAY MONDAY
...JUST MINIMAL POPS OVER THE NORTHEAST CORNER. CONCERNING FIRE
DANGER...THE WINDS GET MARGINALLY STRONG ENOUGH FOR RED FLAG
CRITERIA FOR SOME OF THE CWA LATE DAY MONDAY. THE RELATIVE
HUMIDITIES ARE MARGINAL AS WELL. NO HIGHLIGHTS JUST YET. FOR
TEMPERATURES...MONDAY`S HIGHS CLIMB BACK UP 2-3.5 C ABOVE
SUNDAY`S. TUESDAY`S ARE QUITE SIMILAR TO MONDAY`S. FOR THE LATER
DAYS...WEDNESDAY THROUGH SATURDAY...MODELS SHOW AN UPPER RIDGE TO
THE IMMEDIATE SOUTH OF COLORADO TO BUILD NORTHWARD UP INTO THE
STATE WEDNESDAY AND THURSDAY. BY FRIDAY...THE CENTER IS OVER THE
FOUR CORNERS AND IT`S AXIS IS NORTHWARD ACROSS EASTERN UTAH. BY
SATURDAY...THE CENTER MIGRATES A BIT FURTHER WEST INTO THE EASTERN
GREAT BASIN. THE CWA IS MOSTLY IN WEAK NORTHWESTERLY FLOW ALOFT
ALL FOUR DAYS. THIS ALLOWS FOR A COOLER AIRMASS TO GET INTO THE
CWA FRIDAY AND SATURDAY...WE`LL SEE. THERE IS ALSO A LITTLE BIT OF
MOISTURE HERE AND THERE...BUT NOTHING SIGNIFICANT. TEMPERATURES
ARE PRETTY HOT WEDNESDAY AND THURSDAY...THEN COOL OFF FRIDAY AND
SATURDAY.
&&
.AVIATION...ISOLATED STORMS MOVING OFF THE FOOTHILLS AND PALMER
DIVIDE WILL MOST LIKELY BE HIGH BASED. THAT SAID...THESE CELL WILL
HAVE THE POTENTIAL TO PRODUCE A LIGHT RAIN SHOWER...WIND GUSTS TO
AT LEAST 40 MPH AND DANGEROUS CLOUD-TO-GROUND LIGHTNING. THIS
STORM ACTIVITY IS LIKELY TO MOVE EAST OF THE DENVER METRO BY MID-
EVENING. OVERNIGHT SKIES CLEAR...BUT COULD SEE LOW CLOUDS MOVING
CLOSE TO DIA AROUND MORNING LIGHT. TOMORROW THERE IS A BETTER
CHANCE FOR THUNDERSTORMS CERTAINLY BY AFTERNOON WITH PASSAGE OF AN
UPPER LEVEL WEATHER DISTURBANCE. HAIL...STRONG GUSTY WINDS AND
BRIEF HEAVY RAIN WILL BE POSSIBLE. COULD BRIEFLY SEE MVFR
CONDITIONS WITH THIS AFTERNOON CONVECTION.
&&
.FIRE WEATHER...RED FLAG WARNING WILL REMAIN IN EFFECT UNTIL 8 PM
MDT THIS EVENING FOR COLORADO FIREWEATHER ZONES 211-213-214-216
AND 241. GUSTY WINDS...LOW RELATIVE HUMIDITIES AND DRY FUELS MAIN
REASONS FOR THE WARNING.
&&
.HYDROLOGY...STRONG SLOW MOVING T-STORMS OVER THE FAR NORTHEAST
PLAINS THIS EVENING COULD DEPOSIT 1 TO 2 INCHES OF RAIN IN A
SHORT PERIOD OF TIME. STORMS ELSEWHERE THIS AFTERNOON AND EVENING
ARE NOT EXPECTED TO PRODUCE MUCH MORE THAN A QUARTER OF RAIN.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ211-213-214-
216-241.
&&
$$
SHORT TERM...BAKER
LONG TERM....RJK
AVIATION...BAKER
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1135 AM MDT SAT JUN 22 2013
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 415 AM MDT SAT JUN 22 2013
WEAK OR SHALLOW FRONT IS LOCATED ACROSS MOFFAT/RIO BLANCO COUNTIES
OF NW COLORADO AND NE UTAH. THERE IS SOME (NOT PLENTIFUL) MID
LEVEL MOISTURE STREAMING ACROSS THIS BOUNDARY AS THE RADAR PICKS
UP LOW DBZ RETURNS. VERNAL ASOS HAS STAYED CLR ALL NIGHT...INDICATING
THAT CLOUD BASES ARE ABOVE 12K FEET. TROUGH AXIS OVER THE NRN
INTERMOUNTAIN REGION LIFTS NORTHEAST TOWARD ERN MONTANA/NERN
WYOMING THIS AFTERNOON. SHORT TERM RAP MODEL SHOWS DRIER AIR
SPREADING INTO NE UTAH/NW COLORADO THIS AFTERNOON BEHIND THE
TROUGH AXIS. WHILE THIS IS A REASONABLE SOLUTION...NOT UNUSUAL FOR
AN ISOLATED THUNDERSTORM TO POP OVER THE ERN UINTAS ALONG THE
TRAILING COLD FRONT. GFS40/NAM12 SHOW LOW END CONVECTIVE POTENTIAL
ACROSS THE NRN MOUNTAINS. WILL MAKE A MINOR ADDITION TO THE
FORECAST AND ADD ISOLATED THUNDERSTORMS OVER THE ERN UINTA
MOUNTAINS. OTHERWISE NO CHANGES WITH SOUTHWEST FLOW AND DEEP MIXED
LAYER WILL GENERATE AFTERNOON BREEZES IN THE 20-30 KT
RANGE...ESPECIALLY PARTS OF NW COLORADO.
TONIGHT AND SUNDAY...
THE PERSISTENT SOUTHWEST FLOW THAT HAS BEEN IN PLACE WILL BE
TEMPORARILY DISRUPTED TONIGHT AS A STRONGER PIECE OF ENERGY LIFTS
ACROSS THE NORTHERN ROCKIES INTO THE NORTHERN PLAINS. THIS WILL TURN
THE UPPER FLOW MORE WESTERLY AND HELP PUSH A FRONT INTO THE WESTERN
AND NORTHERN 1/3 OF THE CWA BY MIDNIGHT. WE WILL BE IN THE
SUBSIDENCE PORTION OF THE WAVE OVERNIGHT WHICH SHOULD HELP CLEAR
THINGS OUT AND BRING SLIGHTLY STRONGER INVERSIONS AND COOLER
TEMPERATURES TO MANY PLACES. THE FRONT WILL BE STALLING AND BECOMING
ILL DEFINE BY SUNRISE ON SUNDAY. ALOFT THE SOUTHWESTERLY FLOW WILL
BEGIN TO RE-ESTABLISH ITSELF AS UPSTREAM TROUGHING ONCE AGAIN MOVES
ALONG THE WEST COAST. THERE WILL BE SOME MOISTURE TRAPPED IN THIS
SOUTHWEST FLOW WITH AN ORIGIN ASSOCIATED WITH THE DEEP STREAM OF
HIGH PWATS IN THE NORTHEAST PACIFIC. PWAT PLOTS OVER GJT SHOW THE
NAM MUCH MORE GENEROUS NEAR A HALF OF AN INCH BY PEAK HEATING
SUNDAY...WHILE THE GFS LAGS BELOW A THIRD OF AN INCH. BOTH MODELS
INDICATE SOME WEAK BROAD SCALE ASCENT ASSOCIATED WITH EMBEDDED
ENERGY IN THE FLOW AND THE SUB TROP JET ACROSS THE DESERT SOUTHWEST.
WITH DRY LOW LAYERS THE FOCUS WILL REMAIN ACROSS THE RIDGETOPS WHERE
MOST OF THE ACTION WILL JUST BE BUILDING CU. BETTER MOISTURE GETS
PUSHED UP THE EASTERN DIVIDE IN THE WAKE OF AN FRONT RANGE FRONT. SO
THE BEST CHANCES SEEM TO BE ALONG THE CENTRAL DIVIDE MOUNTAINS WHERE
SMALL POPS WILL BE IN PLACE. TEMPERATURES REMAIN NEAR TO ABOVE
NORMAL.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 415 AM MDT SAT JUN 22 2013
.SUNDAY NIGHT AND MONDAY...
FORCING QUICKLY WANES SUNDAY NIGHT LEAVING DRY CONDITIONS GOING INTO
MONDAY. THETA SURFACES BEGIN TO SHOW STRONG MOISTURE ADVECTION INTO
THE WEST COAST WHICH WILL GRADUALLY BE PICKED UP BY THE SOUTHWEST
FLOW AND DIRECTED TOWARD OUR CWA. HOWEVER THIS WILL NOT BE UNTIL THE
MID WEEK PERIOD SO MONDAY LOOKS TO AGAIN REMAIN MAINLY PRECIPITATION
FREE. WARM TEMPERATURES AND A BATCH OF MID LEVEL COOLING LOOKS TO
BRING SOME GOOD AFTERNOON MIXING IN THIS WARM AIRMASS. OVERALL THE
GRADIENT NOT QUITE AS STRONG AS THE PAST FEW DAYS BUT AFTERNOON
GUSTY WINDS OVER 25 MPH MAY WIDESPREAD AND BRING ANOTHER ROUND OF
CRITICAL FIRE WEATHER CONDITIONS.
TUESDAY THROUGH FRIDAY...
THE WESTERLIES RETREAT NORTHWARD ON TUESDAY...GUSTY AFTERNOON
WINDS MAY STILL EXIST ACROSS THE NORTH. BUT LESS WIND CAN BE
EXPECTED ACROSS THE SOUTH. FOR WEDENESDAY AND BEYOND...STRONG HIGH
PRESSURE BECOMES ANCHORED OVER THE FOUR CORNER STATES. LESS WIND
BUT TURNING HOTTER ACROSS THE ENTIRE AREA. ISOLATED HIGH BASED
THUNDERSTORMS MAY POP OVER THE COLORADO HIGH COUNTRY...BUT THIS
WILL BE DEPENDENT ON HOW MOISTURE WILL TRAPPED BENEATH THE
SUBTROPICAL HIGH.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1134 AM MDT SAT JUN 22 2013
AFTERNOON GUSTS OF 25-30KTS ARE EXPECTED OTHERWISE VFR PREVAILS.
THERE IS A 20 PERCENT CHANCE OF -TSRA NORTH OF KVEL TIL 03Z THIS
EVENING.
&&
.FIRE WEATHER...
ISSUED AT 415 AM SAT JUN 22 2013
FIRE ZONE 201 FUELS HAVE BEEN UPGRADED TO CRITICAL...HOWEVER
HUMIDITY VALUES STAY ABOVE RED FLAG CRITERIA. WILL NOT HOIST A RED
FLAG WARNING FOR ZONE 201. FOR THE REMAINDER OF THE AREA...DEEP
MIXED LAYER AND A STRONG JUNE SUN MEANS ANOTHER DAY OF GUSTY WINDS
AT MANY SPOTS.
GUSTY WINDS AND LOW HUMIDITY WILL CONTINUE THROUGH THE REMAINDER
OF THE WEEKEND...THE QUESTION BEING WHETHER THE WINDS WILL SURPASS
CRITICAL CRITERIA ON SUNDAY. WINDS AT THIS POINT LOOK TO DECREASE
UNDER HEADLINE THRESHOLDS THOUGH LOCAL GUSTS ARE EXPECTED IN THE
AFTERNOON.
ON MONDAY...NEGATIVELY TILTED TROUGH SWIPES NORTHERN REGION OF CWA
AND MAY INCREASE WINDS DURING THE DAY. WILL BE MONITORING THIS
THROUGH THE WEEKEND.
TEMPERATURES LATE NEXT WEEK ASSOCIATED WITH THE BUILDING RIDGE
WILL INCREASE WELL ABOVE NORMAL.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR COZ200-202-203-
207-290>293.
UT...RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR UTZ486-487.
&&
$$
SHORT TERM...PF/15
LONG TERM...15/PF
AVIATION...JDC
FIRE WEATHER...CC
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1120 AM MDT SAT JUN 22 2013
.UPDATE...
&&
.SHORT TERM...TEMPERATURES ON THE PLAINS RUNNING BEHIND YESTERDAY AT
THIS TIME BY 5-10 DEG F...AND 2-6 DEG F BEHIND IN THE HIGH COUNTRY.
THEREFORE THE COOLER MAX TEMPERATURES ALREADY IN THE FCST LOOK
GOOD. LOW CLOUDS BLANKETING MUCH OF NORTHEAST COLORADO EARLIER
THIS MORNING AND STILL OUT NEAR THE NORTHEAST CORNER PARTLY TO
BLAME FOR THE COOLER START TO THE DAY...EVEN WITH A VERY WARM
SOUTHWEST FLOW ALOFT. THIS SWLY FLOW WILL LIKELY MIX DOWN TO THE
SFC PRODUCING GUSTY SWLY WINDS IN THE MTN VALLEYS AND ALONG THE
SRN FOOTHILLS OVER THE NEXT 1-3 HOURS. DEWPTS ALREADY QUITE LOW IN
THESE AREAS...SO RED FLAG WARNING FOR THE MTN VALLEYS AND SRN
FOOTHILLS LOOKS JUSTIFIED. WARNING BEGINS AT NOON MDT. MEANWHILE
HAVE REACHED CONVECTIVE TEMPERATURES IN THE NORTHERN FOOTHILLS AND
ALONG THE SPINE OF THE CONTINENTAL DIVIDE WHERE CU AND TCU ARE
BEGINNING TO FORM. SHOULD SEE THIS PROGRESS CONTINUE THROUGH THE
AFTERNOON AS MID-LEVEL MOISTURE FILTERS IN FROM UTAH AROUND THE
BOTTOM SIDE OF AN UPPER TROUGH APPROACHING WRN WYOMING. HAVE
INCREASED AFTERNOON POPS SLIGHTLY FOR THE NRN MTN RANGES AND NRN
FOOTHILLS...HOWEVER STORMS IN THIS AREA LIKELY TO PRODUCE MORE
GUSTY WIND THAN WETTING RAINFALL THRU EARLY THIS EVENING. ON THE
PLAINS...PLENTY OF CIN OUT THERE NOW...EVEN WITH SFC DEWPOINTS IN
THE MID/UPPER 50S EAST OF A FORT COLLINS-TO-LIMON LINE. MOISTURE
LOOKS SHALLOW ON LAPS AND RUC SOUNDINGS AND CROSS SECTIONS.
THROUGH THE AFTERNOON THE WEST SIDE OF THIS MOISTURE IS PROGGED TO
MIGRATE EAST WITH DRIER SOUTHWESTERLY WINDS COMING OFF THE
FOOTHILLS AND PALMER DIVIDE. BUT ITS OUT ACROSS THE NORTHEAST
CORNER OF THE STATE WHERE LOW-LEVEL MOISTURE WILL HANG TIGHT WITH
SFC BASED CAPES UP AROUND 2500 J/KG BY AROUND 00Z/SUN. SPC HAS
THIS AREA UNDER A SLIGHT RISK FOR SVR T-STORMS. MAY TAKE MOST OF
THE AFTERNOON FOR IT TO DEVELOP OUT THERE WITH ALL OF THE
CIN...PROBABLY NOT UNTIL AFTER 21Z OR 22Z. DAMAGING T-STORM WINDS
AND LARGE HAIL MAIN THREATS. SHOULD SEE MOST OF THIS CONVECTION
WRAPPING UP BY 06Z TONIGHT.
.AVIATION...VFR CONDITIONS ANTICIPATED AT DENVER AREA AIRPORTS
TODAY AND TONIGHT. ISOLATED HIGH BASED AND MOSTLY DRY T-STORMS
DRIFTING OFF THE FOOTHILLS LATE THIS AFTERNOON MAY PRODUCE SOME
GUSTY WINDS...GENERALLY LESS THAN 30 KTS. LITTLE OR NO CHANCE OF
WETTING RAINFALL. SKIES CLEAR OVERNIGHT. LIGHT AND VARIABLE WINDS
AT THIS HOURS EXPECTED TO BECOME SOUTH-SOUTHWEST LATTER THIS
AFTERNOON AT 7-14KTS...THEN DRAINAGE FLOW OVERNIGHT AT LIGHTER
SPEEDS.
&&
.FIRE WEATHER...RED FLAG WARNING GOES INTO EFFECT AT 12 PM MDT
AND RUNS UNTIL 8 PM MDT THIS EVENING FOR COLORADO FIREWEATHER
ZONES 211-213-214-216 AND 241. GUSTY WINDS...LOW RELATIVE
HUMIDITIES AND DRY FUELS MAIN REASONS FOR THE WARNING.
&&
.HYDROLOGY...STRONG STORMS OVER THE FAR NORTHEAST PLAINS THIS
EVENING COULD DROP 1-2 INCHES OF RAIN IN A SHORT PERIOD OF TIME.
OTHERWISE HEAVY RAIN OR FLOODING NOT EXPECTED ELSEWHERE.
&&
.PREV DISCUSSION... /ISSUED 339 AM MDT SAT JUN 22 2013/
SHORT TERM...MAIN CONCERN AGAIN TODAY WILL BE THE SEVERE
POTENTIAL OVER THE PLAINS AND FIRE WEATHER CONCERNS OVER THE
SOUTHERN PORTION OF CWA.
LITTLE CHANGE IN THE SYNOPTIC PATTERN WITH UPPER TROF OVER IDAHO
AND MODEST SOUTHWEST FLOW OVER COLORADO. AT THE SURFACE...LOW
PRESSURE OVER FAR EAST CENTRAL COLORADO WHILE SEVERAL SURGES FROM
LAST NIGHT CONVECTION HAS REPLENISHED THE LOW LEVEL MOISTURE.
SURFACE DEWPOINTS HAVE INCREASED INTO THE MID 40S TO MID 50S WHILE
INTEGRATED PW VALUES ARE AROUND 6 TENTHS OF AN INCH OVER THE FRONT
RANGE WHICH IS JUST SLIGHTLY DOWNWARD FROM 24 HOURS AGO. THIS
MOISTURE WILL AGAIN FLUSH OUT AS THE DRIER AIR MIXES DOWN. THE
QUESTION WILL BE WHERE WILL THE BOUNDARY END UP WITH THE DRIER AIR
TO THE SOUTHWEST AND MORE MOIST AIR TO THE NORTHEAST. APPEARS
STORMS MAY FIRE A BIT MORE TO THE SOUTHWEST THIS AFTERNOON VS.
FRIDAY AND BEST GUESS WOULD BE ALONG A LINE FROM LIMON TO GREELEY
AND POINTS NORTH AND EAST. LATEST WRF SIMULATED IMAGERY SHOWING
SOMETHING SIMILAR TO ABOVE SCENARIO.
STORMS THAT DO DEVELOP WILL PROBABLY BECOME SEVERE WITH SURFACE
BASED CAPES FROM 2000-3000J/KG AND MODEST MID LEVEL FLOW. FURTHER
WEST...WITH THE DRIER AIR MIXING DOWN THERE MAY BE SOME HIGH BASED
SHOWERS WITH GUSTY WINDS THE MAIN THREAT. AS LIKE THIS
NIGHT...EXPECT OUTFLOW BOUNDARIES TO USHER IN HIGHER LOW LEVEL
MOISTURE BY SUNDAY MORNING.
LONG TERM...SW FLOW ALOFT WILL REMAIN OVER THE AREA SUN AND MON.
APPEARS ANOTHER WEAK COOL FNT WILL AFFECT NERN CO ON SUN WITH ESE
LOW LVL FLOW WHICH SHOULD ALLOW DEEPER MOISTURE TO STAY IN PLACE
ACROSS THE PLAINS AND POSSIBLY THE NRN FOOTHILLS. EXPECT THERE
WILL BE A DENVER CYCLONE BY AFTN WITH A CONVERGENCE ZONE SETTING
ALONG OR JUST EAST OF THE FRONT RANGE URBAN CORRIDOR. WITH A
FAVORABLE SHEAR PROFILE IN PLACE AND CAPES BY AFTN RANGING FM
1500-2500 J/KG COULD SEE AN ACTIVE AFTN AND EVENING OVER THE NERN
PLAINS. IN THE MTNS AND HIGHER VALLEYS DRIER AIR WILL REMAIN
PLACE ALTHOUGH COULD SEE A FEW HIGH BASED STORMS EAST OF THE
DIVIDE. FIRE DANGER WILL CONTINUE CRITICAL IN THE HIGHER VALLEYS
AND OVER PARK COUNTY. AS FOR HIGHS TEMPS SHOULD BE A FEW DEGREES
COOLER OVER NERN CO WITH READINGS MAINLY IN THE 80S.
BY MON THE LOW LEVEL FLOW WILL BECOME MORE SLY ON MON OVER NERN CO
WHICH WILL SCOUR OUT LOW LEVEL MOISTURE EXCEPT OVER THE FAR NERN
PLAINS. THERE WILL BE SOME SFC CONVERGENCE AND HIGHER CAPES
NORTHEAST OF A NEW RAYMER TO FORT MORGAN TO LIMON LINE SO MAY SEE
A SLIGHT CHC OF TSTMS BY MID TO LATE AFTN. ELSEWHERE APPEARS A DRY
AIRMASS WILL BE IN PLACE SO WILL KEEP THE REST OF THE AREA DRY.
ONCE AGAIN FIRE DANGER WILL REMAIN VERY HIGH OVER THE HIGHER
VALLEYS AND PARK COUNTY MON AFTN. HIGHS ON MON OVER NERN CO WILL
RISE BACK INTO THE LOWER TO MID 90S.
FOR TUE THE FLOW ALOFT WILL BECOME MORE WLY AS AN UPPER LEVEL
RIDGE BEGINS TO BUILD OVER THE SRN ROCKIES WITH A VERY DRY AIRMASS
IN PLACE. FIRE DANGER WILL REMAIN VERY HIGH ALTHOUGH LOW LEVEL
WINDS MAY NOT BE QUITE AS GUSTY. HIGHS ON TUE WILL RISE INTO THE
90S ACROSS NERN CO. BY WED AND THU AN UPPER LEVEL HIGH WILL BE
CENTERED OVER SWRN CO WITH WLY FLOW ALOFT ACROSS NRN CO. MOISTURE
BOTH DAYS STILL LOOKS MEAGER SO WILL KEEP FCST DRY. HIGHS BOTH
DAYS OVER NERN CO LOOK TO BE IN THE 95 TO 100 DEGREE RANGE.
BY FRI BOTH THE ECMWF AND GFS MOVE THE UPPER LEVEL HIGH A LITTLE
FURTHER WEST WHICH ALLOWS FOR THE FLOW ALOFT TO BECOME MORE NWLY.
BOTH MODELS TRY TO ENTRAIN SOME SUB TROPICAL MOISTURE INTO THE
FLOW AS A WEAK COOL FNT MOVES INTO NERN CO. THUS THIS MAY LEAD TO
A SLIGHT CHC OF AFTN AND EVENING TSTMS OVER THE HIGHER TERRAIN AND
THE PLAINS.
AVIATION...NORTHWEST SURFACE WINDS TO GRADUALLY TURN NORTHEAST
AND EAST BY EARLY AFTERNOON. THEN SOUTHWEST WINDS WILL BEGIN TO
MIX DOWN BY LATE AFTERNOON. THUNDERSTORMS MAY GET A LITTLE CLOSER
TODAY BUT STILL THINK MOST OF THE ACTIVITY WILL BE EAST AND
NORTHEAST OF THE TERMINALS AND WON`T MENTION FOR NOW.
FIRE WEATHER...A REPEAT PERFORMANCE THIS AFTERNOON WITH RED FLAG
CONDITIONS AGAIN ACROSS MTN VALLEYS...PARK COUNTY AND PALMER
DIVIDE. ZONE 216 IS BORDERLINE FOR THE GUSTY WINDS BUT LOOKS LIKE
SHOULD BE A LITTLE STRONGER THAN FRIDAY AND WILL ADD TO THE RED
FLAG WARNINGS.
HYDROLOGY...STRONG STORMS OVER THE FAR NORTHEAST PLAINS COULD
DROP 1-2 INCHES OF RAIN IN A SHORT PERIOD OF TIME. FURTHER
WEST...VERY LITTLE RAINFALL EXPECTED OVER THE FRONT RANGE.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ211-213-214-
216-241.
&&
$$
SHORT TERM...BAKER/ENTREKIN
LONG TERM....RPK
AVIATION...BAKER/ENTREKIN
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
415 AM MDT SAT JUN 22 2013
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 415 AM MDT SAT JUN 22 2013
WEAK OR SHALLOW FRONT IS LOCATED ACROSS MOFFAT/RIO BLANCO COUNTIES
OF NW COLORADO AND NE UTAH. THERE IS SOME (NOT PLENTIFUL) MID
LEVEL MOISTURE STREAMING ACROSS THIS BOUNDARY AS THE RADAR PICKS
UP LOW DBZ RETURNS. VERNAL ASOS HAS STAYED CLR ALL NIGHT...INDICATING
THAT CLOUD BASES ARE ABOVE 12K FEET. TROUGH AXIS OVER THE NRN
INTERMOUNTAIN REGION LIFTS NORTHEAST TOWARD ERN MONTANA/NERN
WYOMING THIS AFTERNOON. SHORT TERM RAP MODEL SHOWS DRIER AIR
SPREADING INTO NE UTAH/NW COLORADO THIS AFTERNOON BEHIND THE
TROUGH AXIS. WHILE THIS IS A REASONABLE SOLUTION...NOT UNUSUAL FOR
AN ISOLATED THUNDERSTORM TO POP OVER THE ERN UINTAS ALONG THE
TRAILING COLD FRONT. GFS40/NAM12 SHOW LOW END CONVECTIVE POTENTIAL
ACROSS THE NRN MOUNTAINS. WILL MAKE A MINOR ADDITION TO THE
FORECAST AND ADD ISOLATED THUNDERSTORMS OVER THE ERN UINTA
MOUNTAINS. OTHERWISE NO CHANGES WITH SOUTHWEST FLOW AND DEEP MIXED
LAYER WILL GENERATE AFTERNOON BREEZES IN THE 20-30 KT
RANGE...ESPECIALLY PARTS OF NW COLORADO.
TONIGHT AND SUNDAY...
THE PERSISTENT SOUTHWEST FLOW THAT HAS BEEN IN PLACE WILL BE
TEMPORARILY DISRUPTED TONIGHT AS A STRONGER PIECE OF ENERGY LIFTS
ACROSS THE NORTHERN ROCKIES INTO THE NORTHERN PLAINS. THIS WILL TURN
THE UPPER FLOW MORE WESTERLY AND HELP PUSH A FRONT INTO THE WESTERN
AND NORTHERN 1/3 OF THE CWA BY MIDNIGHT. WE WILL BE IN THE
SUBSIDENCE PORTION OF THE WAVE OVERNIGHT WHICH SHOULD HELP CLEAR
THINGS OUT AND BRING SLIGHTLY STRONGER INVERSIONS AND COOLER
TEMPERATURES TO MANY PLACES. THE FRONT WILL BE STALLING AND BECOMING
ILL DEFINE BY SUNRISE ON SUNDAY. ALOFT THE SOUTHWESTERLY FLOW WILL
BEGIN TO RE-ESTABLISH ITSELF AS UPSTREAM TROUGHING ONCE AGAIN MOVES
ALONG THE WEST COAST. THERE WILL BE SOME MOISTURE TRAPPED IN THIS
SOUTHWEST FLOW WITH AN ORIGIN ASSOCIATED WITH THE DEEP STREAM OF
HIGH PWATS IN THE NORTHEAST PACIFIC. PWAT PLOTS OVER GJT SHOW THE
NAM MUCH MORE GENEROUS NEAR A HALF OF AN INCH BY PEAK HEATING
SUNDAY...WHILE THE GFS LAGS BELOW A THIRD OF AN INCH. BOTH MODELS
INDICATE SOME WEAK BROAD SCALE ASCENT ASSOCIATED WITH EMBEDDED
ENERGY IN THE FLOW AND THE SUB TROP JET ACROSS THE DESERT SOUTHWEST.
WITH DRY LOW LAYERS THE FOCUS WILL REMAIN ACROSS THE RIDGETOPS WHERE
MOST OF THE ACTION WILL JUST BE BUILDING CU. BETTER MOISTURE GETS
PUSHED UP THE EASTERN DIVIDE IN THE WAKE OF AN FRONT RANGE FRONT. SO
THE BEST CHANCES SEEM TO BE ALONG THE CENTRAL DIVIDE MOUNTAINS WHERE
SMALL POPS WILL BE IN PLACE. TEMPERATURES REMAIN NEAR TO ABOVE
NORMAL.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 415 AM MDT SAT JUN 22 2013
.SUNDAY NIGHT AND MONDAY...
FORCING QUICKLY WANES SUNDAY NIGHT LEAVING DRY CONDITIONS GOING INTO
MONDAY. THETA SURFACES BEGIN TO SHOW STRONG MOISTURE ADVECTION INTO
THE WEST COAST WHICH WILL GRADUALLY BE PICKED UP BY THE SOUTHWEST
FLOW AND DIRECTED TOWARD OUR CWA. HOWEVER THIS WILL NOT BE UNTIL THE
MID WEEK PERIOD SO MONDAY LOOKS TO AGAIN REMAIN MAINLY PRECIPITATION
FREE. WARM TEMPERATURES AND A BATCH OF MID LEVEL COOLING LOOKS TO
BRING SOME GOOD AFTERNOON MIXING IN THIS WARM AIRMASS. OVERALL THE
GRADIENT NOT QUITE AS STRONG AS THE PAST FEW DAYS BUT AFTERNOON
GUSTY WINDS OVER 25 MPH MAY WIDESPREAD AND BRING ANOTHER ROUND OF
CRITICAL FIRE WEATHER CONDITIONS.
TUESDAY THROUGH FRIDAY...
THE WESTERLIES RETREAT NORTHWARD ON TUESDAY...GUSTY AFTERNOON
WINDS MAY STILL EXIST ACROSS THE NORTH. BUT LESS WIND CAN BE
EXPECTED ACROSS THE SOUTH. FOR WEDENESDAY AND BEYOND...STRONG HIGH
PRESSURE BECOMES ANCHORED OVER THE FOUR CORNER STATES. LESS WIND
BUT TURNING HOTTER ACROSS THE ENTIRE AREA. ISOLATED HIGH BASED
THUNDERSTORMS MAY POP OVER THE COLORADO HIGH COUNTRY...BUT THIS
WILL BE DEPENDENT ON HOW MOISTURE WILL TRAPPED BENEATH THE
SUBTROPICAL HIGH.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 415 AM MDT SAT JUN 22 2013
AFTERNOON GUSTS OF 25-30KTS ARE EXPECTED OTHERWISE VFR PREVAILS.
THERE IS A 20 PERCENT CHANCE OF AN AFTERNOON -TSRA NORTH OF KVEL.
&&
.FIRE WEATHER...
ISSUED AT 415 AM SAT JUN 22 2013
FIRE ZONE 201 FUELS HAVE BEEN UPGRADED TO CRITICAL...HOWEVER
HUMIDITY VALUES STAY ABOVE RED FLAG CRITERIA. WILL NOT HOIST A RED
FLAG WARNING FOR ZONE 201. FOR THE REMAINDER OF THE AREA...DEEP
MIXED LAYER AND A STRONG JUNE SUN MEANS ANOTHER DAY OF GUSTY WINDS
AT MANY SPOTS.
GUSTY WINDS AND LOW HUMIDITY WILL CONTINUE THROUGH THE REMAINDER
OF THE WEEKEND...THE QUESTION BEING WHETHER THE WINDS WILL SURPASS
CRITICAL CRITERIA ON SUNDAY. WINDS AT THIS POINT LOOK TO DECREASE
UNDER HEADLINE THRESHOLDS THOUGH LOCAL GUSTS ARE EXPECTED IN THE
AFTERNOON.
ON MONDAY...NEGATIVELY TILTED TROUGH SWIPES NORTHERN REGION OF CWA
AND MAY INCREASE WINDS DURING THE DAY. WILL BE MONITORING THIS
THROUGH THE WEEKEND.
TEMPERATURES LATE NEXT WEEK ASSOCIATED WITH THE BUILDING RIDGE
WILL INCREASE WELL ABOVE NORMAL.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...RED FLAG WARNING FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR
COZ200-202-203-207-290>293.
UT...RED FLAG WARNING FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR
UTZ486-487.
&&
$$
SHORT TERM...PF/15
LONG TERM...15/PF
AVIATION...PF
FIRE WEATHER...CC
AREA FORECAST DISCUSSION
NWS ALBANY NY
659 PM EDT SAT JUN 22 2013
.SYNOPSIS...
WARM AND HUMID CONDITIONS WILL CONTINUE THROUGH THE REMAINDER OF
THE WEEKEND AND INTO THE START OF THE NEW WORK WEEK. THERE WILL BE
THE CHANCE FOR MAINLY AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS UNDER VARIABLE CLOUDS.
&&
.NEAR TERM /THROUGH SUNDAY/...
AS OF 645 PM EDT...THE TREND DURING THE PAST HOUR OR SO IS THAT
SCATTERED SHOWERS HAVE BECOME LESS SCATTERED. A WEAK DISTURBANCE HAS
SET THEM OFF...BUT THE RUC ANALYSIS ASSOCIATED WITH THIS SHORT WAVE
APPEARS TO BE WEAKENING.
THE HRRR AND 18Z NAM INDICATE THIS WILL INDEED BE THE CASE.
HOWEVER...THE WFOWRF HAS INDICATED OTHERWISE...THAT THESE SHOWERS
WILL BECOME ENHANCED AND PROBABLY CONTAIN THUNDER AS WELL.
HOWEVER...LOOKING AT SPC PARAMETERS IT APPEARS THAT THERE WILL NOT
BE AN INCREASE IN MOISTURE OR INSTABILITY (ACTUALLY SHOULD BE
LOWERING WITH LOSS OF HEATING). FORCING APPEARS RATHER MINIMAL AT
THIS TIME WITH THE BEST LOW LEVEL JET CORE ACROSS THE ST LAWRENCE
VALLEY. BELIEVE THE WFOWRF IS PROBABLY NOT CORRECT BUT IT IS
CERTAINLY POSSIBLE.
FOR THIS UPDATE FOLLOWED THE PREVIOUS FORECASTER`S THINKING ALTHOUGH
I TRIMMED DOWN POPS A LITTLE AND ONLY INCLUDE A CHANCE OF THUNDER
SINCE THERE HAVE BEEN VIRTUALLY NO CGS OVER OUR REGION SO FAR.
CLOUDS WILL CONTINUE TO INCREASE FOR AWHILE AND ISOLATED SHOWERS
SHOULD MAKE IT INTO THE CAPITAL REGION AND EVEN SOUTH...BUT AGAIN
NOT EVERYONE WILL HAVE SEE A SHOWER.
FOR THE REST OF THE DAYLIGHT HOURS...LOOK FOR MOST OF US TO REMAIN
RAIN FREE BUT SHOWER IS POSSIBLE FROM THE CAPITAL DISTRICT
NORTHWARD. IT WILL REMAIN SOMEWHAT HUMID AND WARM WITH TEMPERATURES
ONLY VERY SLOW TO FALL BACK INTO THE MID AND UPPER 70S. A SOUTH WIND
WILL AVERAGE 5 TO 10 MPH.
CLOUD COVER FORECAST TONIGHT WILL BE PROBLEMATIC AS CONVECTIVE
DEBRIS ALONG WITH A INCREASE IN LOW LEVEL MOISTURE COULD RESULT IN
TWO CLOUD LAYERS /THE BEST POTENTIAL ALONG AND NORTH OF I90/. SO FOR
NOW...WE WILL CALL IT PT-MOCLOUDY AND KEEP OVERNIGHT LOW TEMPS A BIT
MILD AND CLOSER THE MET MOS VALUES WHICH IS IN AGREEMENT WITH THE
HOURLY LAV/LAMP. LOWS FOR LOWS IN THE 60S...UPPER 60S LOCALLY IN THE
TRI-CITY REGION. ALL INDICATIONS THOUGH POINT TO AN INCREASE IN
CLOUD COVER THIS EVENING...DECREASING OVERNIGHT. DID TWEAK THE CLOUD
COVER A BIT AS WELL ESPECIALLY DURING THE OVERNIGHT.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
WITH A LACK OF STRONG FORCING MECHANISMS IN THE SHORT TERM
COMBINING WITH INCREASE WARMTH AND HUMID CONDITIONS AROUND THE
PERIPHERY OF BERMUDA HIGH...THE CHANCE FOR MAINLY AFTERNOON AND
EARLY EVENING SHOWERS/THUNDERSTORMS. LAPSE RATES ARE MARGINAL WITH
VALUES LESS THAN 6/KM IN THE H850-500 LAYER...HOWEVER...SBCAPES
ARE EXPECTED TO RANGE BETWEEN 1K-2K J/KG DURING THE PEAK HEATING AS
TEMPERATURES CLIMB WELL INTO THE 80S FOR MANY LOCATIONS. OVERNIGHT
LOWS WILL GENERALLY RANGE IN THE 60S...BUT WOULD NOT BE RULE OUT
OUR FIRST 70 DEGREE OVERNIGHT LOW DURING THE NEXT COUPLE OF
NIGHTS.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
THE WEATHER PATTERN LOOKS UNSETTLED THROUGHOUT THE EXTENDED PERIOD.
THE WEAK RIDGE TO OUR SOUTH LOOKS TO SLOWLY RETROGRADE
WESTWARD...STRENGTHENING AS IT SETS UP SHOP OVER THE WESTERN CONUS
BY LATE IN THE WEEK. IN RESPONSE...IT LOOKS AS IF A LONG WAVE TROUGH
WILL SLOWLY DIG INTO THE EASTERN CONUS.
THE DEVIL IN THE DETAILS ARE HARD TO PINPOINT AT THIS TIME. WHAT WE
DO KNOW IS THAT TEMPERATURES WILL SLOWLY COOL DOWN...AND BY NEXT
WEEKEND...SHOULD BE RUNNING SLIGHTLY BELOW NORMAL. THE TRICKIER PART
IS TIMING SPECIFIC DISTURBANCES THAT WILL PROVIDE A FOCUS FOR SHOWER
AND THUNDERSTORMS.
IT LOOKS AS IF TUESDAY WE WILL STILL BE IN A SOUPY AIR MASS WITH
STILL NO GOOD TRIGGER OTHER THAN DIURNAL HEATING TO SPARK SHOWERS
AND THUNDERSTORMS. SO ON THAT DAY...WENT WITH SLIGHT CHANCES OF
SHOWERS EARLY...LOW POPS (30 PERCENT CHANCES) OF SHOWERS AND
THUNDERSTORMS DURING THE AFTERNOON AND EVENING HOURS. TEMPERATURES
WILL CLIMB WELL INTO THE 80S...POSSIBLY TOUCHING 90 IN THE VALLEY
AREAS SOUTH OF ALBANY. IT WILL BE RATHER HUMID AS WELL.
WEDNESDAY...A WEAK COLD FRONTS LOOKS TO CROSS THE REGION SOMETIME
DURING THE DAY...TRIGGERING AGAIN MAINLY LATE AFTERNOON AND EVENING
THUNDERSTORMS. TEMPERATURES LOOK SLIGHTLY COOLER BUT STILL
WARM...WELL INTO THE 80S MOST PLACES AND STILL A BIT HUMID.
A VERY WEAK HIGH PRESSURE MIGHT BRIEFLY BUILD IN WEDNESDAY NIGHT
INTO EARLY THURSDAY SO WHILE WE CANNOT ENTIRELY RULE OUT SHOWERS (20
POPS) WE BELIEVE THIS COULD BE A BRIEF "DRIER" PERIOD WITH SLIGHTLY
LOWER HUMIDITY.
LATER THURSDAY...ALL MODELS INDICATE SURFACE LOW PRESSURE AT THE
SURFACE AND ALOFT WILL HEAD FROM THE GREAT LAKES TOWARD OUR REGION.
THIS SYSTEM LOOKS TO BE THE ONE THAT REALLY BEGINS TO BUCKLE THE
RIDGE IN THE EAST. THIS SYSTEM COULD BRING AN ORGANIZED AREA OF
SHOWERS AND EMBEDDED THUNDERSTORMS (POSSIBLY EVEN A MULTIPLE
CONVECTIVE SYSTEM - MCS) OUR WAY LATE THURSDAY INTO FRIDAY.
HIGHS BOTH THURSDAY AND FRIDAY LOOK TO BE IN THE MID TO UPPER 70S
ACROSS THE HIGHER TERRAIN...AROUND 80 IN THE VALLEYS. IF EITHER DAY
TURNS OUT TO BE A WASHOUT (A POSSIBILITY)...TEMPERATURES WOULD BE A
LITTLE LOWER.
THEN...YET ANOTHER LOW PRESSURE AREA AT THE SURFACE AND ALOFT COULD
BRING YET ANOTHER ROUND OF DISTURBED WEATHER ON FRIDAY INTO EARLY
SATURDAY.
WHILE THE 12Z EUROPEAN HAS A SURFACE LOW MOVING ON BY
SATURDAY...LOW PRESSURE ALOFT LINGERS ACROSS THE GREAT LAKES WHICH
WOULD COOL THE MID AND UPPER LEVELS OF THE ATMOSPHERE TO KEEP THE
THREAT OF ADDITIONAL SHOWERS AND THUNDERSTORMS AROUND...ESPECIALLY
SATURDAY AFTERNOON.
HIGHS SATURDAY MIGHT BE MAINLY IN THE 70S...EXCEPT LOWER 80S ACROSS
THE MID HUDSON VALLEY.
OVERNIGHT LOWS THROUGHOUT THE PERIOD WILL GENERALLY BE IN THE
60S...EXCEPT SOME 50S ACROSS THE HIGHER TERRAIN BY FRIDAY NIGHT.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
A NEARLY STATIONARY FRONTAL BOUNDARY WILL REMAIN LOCATED JUST NORTH
OF THE UNITED STATES/CANADIAN BORDER. A WEAK DISTURBANCE WILL PASS
ALONG THIS BOUNDARY LATER TODAY.
FLYING CONDITIONS ARE CURRENTLY VFR WITH MAINLY JUST SOME SCT HIGH
CLOUDS OVER THE AREA. VFR CONDITIONS LOOK TO CONTINUE THROUGH THE
AFTERNOON AND INTO THE EVENING...AS LOWER TO MID LEVEL CLOUDS START
TO INCREASE AS THE WEAK DISTURBANCE MOVES ALONG THE BOUNDARY TO OUR
NORTH. A FEW PASSING SHOWERS AND AN ISOLD THUNDERSTORM ARE POSSIBLE
BY THIS EVENING INTO TONIGHT...ALTHOUGH SINCE COVERAGE WILL BE
FAIRLY LIMITED...WE WILL LIMIT MENTION TO JUST VCSH FOR THE NORTHERN
TERMINALS OF KGFL/KALB/KPSF.
DUE TO THE CLOUDS AND A LIGHT SOUTHERLY BREEZE OVERNIGHT...NO FOG IS
ANTICIPATED AT KGFL/KALB. CLOUDS MAY BE THINNER AT KPSF/KPOU AND IF
WINDS LIGHTEN UP ENOUGH AFTER MIDNIGHT...THEN SOME BR/FG MAY BE
POSSIBLE. FOR NOW...WILL LIMIT TO JUST MVFR DUE TO THE UNCERTAINTY
ON TIMING/EXTENT AFTER ABOUT 07Z.
AFTER SUNRISE...ANY FOG SHOULD DISSIPATE AND VFR CONDITIONS WILL BE
IN PLACE FOR ALL TERMINALS. CLOUDS SHOULD SCT OUT FOR THE REMAINDER
OF THE MORNING AND EARLY AFTN...ALTHOUGH ADDITIONAL SHOWERS ARE
POSSIBLE LATER ON SUNDAY.
OUTLOOK...
SUN PM-THU...MAINLY VFR. CHC -TSRA/-SHRA MAINLY DURING THE AFTN
INTO THE EVNG.
&&
.FIRE WEATHER...
AS HIGHER LOWER LEVEL MOISTURE CONTINUES TO ADVECT INTO THE
REGION...OVERNIGHT DEW FORMATION ALONG WITH THE CHANCE FOR
ADDITIONAL SHOWERS AND THUNDERSTORMS WILL KEEP THE LOW LEVELS
RATHER MOIST THE NEXT FEW DAYS.
&&
.HYDROLOGY...
OVERALL...FLOWS WILL CONTINUE TO GRADUALLY LOWER CLOSER TO
SEASONAL NORMAL LEVELS OVER THE NEXT 5 DAYS.
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED
THROUGH EARLY NEXT WEEK...HOWEVER WIDESPREAD RAINFALL IS NOT
ANTICIPATED AT THIS TIME...AND NOT ALL LOCATIONS WILL RECEIVE THE
RAINFALL.
AS THE AIR MASS GETS MORE HUMID...SLOW MOVING THUNDERSTORMS COULD
PRODUCE A QUICK INCH OR SO OF RAINFALL WITH HIGHER THAN NORMAL
PWAT VALUES OVER THE HSA. SOME POOR DRAINAGE FLOODING OF LOW LYING
AREAS...AND PONDING OF WATER ON ROADWAYS WILL BE POSSIBLE ANY DAY.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...BGM
NEAR TERM...HWJIV/BGM
SHORT TERM...BGM
LONG TERM...HWJIV
AVIATION...FRUGIS
FIRE WEATHER...BGM
HYDROLOGY...BGM
AREA FORECAST DISCUSSION
NWS ALBANY NY
355 PM EDT SAT JUN 22 2013
.SYNOPSIS...
WARM AND HUMID CONDITIONS WILL CONTINUE THROUGH THE REMAINDER OF
THE WEEKEND AND INTO THE START OF THE NEW WORK WEEK. THERE WILL BE
THE CHANCE FOR MAINLY AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS UNDER VARIABLE CLOUDS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
REGIONAL RADARS THIS AFTERNOON SHOW A WEAK COMPLEX OF CONVECTION
ACROSS LAKE ONTARIO WITH MINIMAL CG/S PER THE NLDN. THIS
APPEARS...PER THE H2O VAPOR LOOP...TO BE ASSOCIATED WITH A WEAK
SHORT WAVE THAT THE LATEST RAP MODEL SUGGESTS WILL MOVE ACROSS THE
NORTHERN 2/3RDS OF THE REGION THROUGH THIS EVENING. WE WILL PLACE
POPS AOA 20-30% AS THE LEADING EDGE WOULD APPROACH AT THE TIME
WHEN THE SUN IS CLOSE TO SETTING FURTHER REDUCING INSTABILITY. IN
FACT...LATEST RUN OF THE HRRR AND 4KM SPC WRF REFLECTIVITIES
SUGGEST THIS INITIAL BATCH WOULD WEAKEN AND ATTEMPT TO REDEVELOP
NORTH OF I90 OVERNIGHT. THIS SECOND SURGE WOULD BE ON THE LEADING
EDGE OF ADDITIONAL WARMTH AND HUMIDITY AS SEEN IN THE THETA-E
FIELDS. HOWEVER...FORCING APPEARS RATHER MINIMAL AT THIS TIME WITH
THE BEST LOW LEVEL JET CORE ACROSS THE ST LAWRENCE VALLEY.
CLOUD COVER FORECAST WILL BE PROBLEMATIC AS CONVECTIVE DEBRIS
ALONG WITH A INCREASE IN LOW LEVEL MOISTURE COULD RESULT IN TWO
CLOUD LAYERS /THE BEST POTENTIAL ALONG AND NORTH OF I90/. SO FOR
NOW...WE WILL CALL IT PT-MOCLOUDY AND KEEP OVERNIGHT LOW TEMPS A
BIT MILD AND CLOSER THE MET MOS VALUES WHICH IS IN AGREEMENT WITH
THE HOURLY LAV/LAMP.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
WITH A LACK OF STRONG FORCING MECHANISMS IN THE SHORT TERM
COMBINING WITH INCREASE WARMTH AND HUMID CONDITIONS AROUND THE
PERIPHERY OF BERMUDA HIGH...THE CHANCE FOR MAINLY AFTERNOON AND
EARLY EVENING SHOWERS/THUNDERSTORMS. LAPSE RATES ARE MARGINAL WITH
VALUES LESS THAN 6/KM IN THE H850-500 LAYER...HOWEVER...SBCAPES
ARE EXPECTED TO RANGE BETWEEN 1K-2K J/KG DURING THE PEAK HEATING AS
TEMPERATURES CLIMB WELL INTO THE 80S FOR MANY LOCATIONS. OVERNIGHT
LOWS WILL GENERALLY RANGE IN THE 60S...BUT WOULD NOT BE RULE OUT
OUR FIRST 70 DEGREE OVERNIGHT LOW DURING THE NEXT COUPLE OF
NIGHTS.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
THE WEATHER PATTERN LOOKS UNSETTLED THROUGHOUT THE EXTENDED PERIOD.
THE WEAK RIDGE TO OUR SOUTH LOOKS TO SLOWLY RETROGRADE
WESTWARD...STRENGTHENING AS IT SETS UP SHOP OVER THE WESTERN CONUS
BY LATE IN THE WEEK. IN RESPONSE...IT LOOKS AS IF A LONG WAVE TROUGH
WILL SLOWLY DIG INTO THE EASTERN CONUS.
THE DEVIL IN THE DETAILS ARE HARD TO PINPOINT AT THIS TIME. WHAT WE
DO KNOW IS THAT TEMPERATURES WILL SLOWLY COOL DOWN...AND BY NEXT
WEEKEND...SHOULD BE RUNNING SLIGHTLY BELOW NORMAL. THE TRICKIER PART
IS TIMING SPECIFIC DISTURBANCES THAT WILL PROVIDE A FOCUS FOR SHOWER
AND THUNDERSTORMS.
IT LOOKS AS IF TUESDAY WE WILL STILL BE IN A SOUPY AIR MASS WITH
STILL NO GOOD TRIGGER OTHER THAN DIURNAL HEATING TO SPARK SHOWERS
AND THUNDERSTORMS. SO ON THAT DAY...WENT WITH SLIGHT CHANCES OF
SHOWERS EARLY...LOW POPS (30 PERCENT CHANCES) OF SHOWERS AND
THUNDERSTORMS DURING THE AFTERNOON AND EVENING HOURS. TEMPERATURES
WILL CLIMB WELL INTO THE 80S...POSSIBLY TOUCHING 90 IN THE VALLEY
AREAS SOUTH OF ALBANY. IT WILL BE RATHER HUMID AS WELL.
WEDNESDAY...A WEAK COLD FRONTS LOOKS TO CROSS THE REGION SOMETIME
DURING THE DAY...TRIGGERING AGAIN MAINLY LATE AFTERNOON AND EVENING
THUNDERSTORMS. TEMPERATURES LOOK SLIGHTLY COOLER BUT STILL
WARM...WELL INTO THE 80S MOST PLACES AND STILL A BIT HUMID.
A VERY WEAK HIGH PRESSURE MIGHT BRIEFLY BUILD IN WEDNESDAY NIGHT
INTO EARLY THURSDAY SO WHILE WE CANNOT ENTIRELY RULE OUT SHOWERS (20
POPS) WE BELIEVE THIS COULD BE A BRIEF "DRIER" PERIOD WITH SLIGHTLY
LOWER HUMIDITY.
LATER THURSDAY...ALL MODELS INDICATE SURFACE LOW PRESSURE AT THE
SURFACE AND ALOFT WILL HEAD FROM THE GREAT LAKES TOWARD OUR REGION.
THIS SYSTEM LOOKS TO BE THE ONE THAT REALLY BEGINS TO BUCKLE THE
RIDGE IN THE EAST. THIS SYSTEM COULD BRING AN ORGANIZED AREA OF
SHOWERS AND EMBEDDED THUNDERSTORMS (POSSIBLY EVEN A MULTIPLE
CONVECTIVE SYSTEM - MCS) OUR WAY LATE THURSDAY INTO FRIDAY.
HIGHS BOTH THURSDAY AND FRIDAY LOOK TO BE IN THE MID TO UPPER 70S
ACROSS THE HIGHER TERRAIN...AROUND 80 IN THE VALLEYS. IF EITHER DAY
TURNS OUT TO BE A WASHOUT (A POSSIBILITY)...TEMPERATURES WOULD BE A
LITTLE LOWER.
THEN...YET ANOTHER LOW PRESSURE AREA AT THE SURFACE AND ALOFT COULD
BRING YET ANOTHER ROUND OF DISTURBED WEATHER ON FRIDAY INTO EARLY
SATURDAY.
WHILE THE 12Z EUROPEAN HAS A SURFACE LOW MOVING ON BY
SATURDAY...LOW PRESSURE ALOFT LINGERS ACROSS THE GREAT LAKES WHICH
WOULD COOL THE MID AND UPPER LEVELS OF THE ATMOSPHERE TO KEEP THE
THREAT OF ADDITIONAL SHOWERS AND THUNDERSTORMS AROUND...ESPECIALLY
SATURDAY AFTERNOON.
HIGHS SATURDAY MIGHT BE MAINLY IN THE 70S...EXCEPT LOWER 80S ACROSS
THE MID HUDSON VALLEY.
OVERNIGHT LOWS THROUGHOUT THE PERIOD WILL GENERALLY BE IN THE
60S...EXCEPT SOME 50S ACROSS THE HIGHER TERRAIN BY FRIDAY NIGHT.
&&
.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
A NEARLY STATIONARY FRONTAL BOUNDARY WILL REMAIN LOCATED JUST NORTH
OF THE UNITED STATES/CANADIAN BORDER. A WEAK DISTURBANCE WILL PASS
ALONG THIS BOUNDARY LATER TODAY.
FLYING CONDITIONS ARE CURRENTLY VFR WITH MAINLY JUST SOME SCT HIGH
CLOUDS OVER THE AREA. VFR CONDITIONS LOOK TO CONTINUE THROUGH THE
AFTERNOON AND INTO THE EVENING...AS LOWER TO MID LEVEL CLOUDS START
TO INCREASE AS THE WEAK DISTURBANCE MOVES ALONG THE BOUNDARY TO OUR
NORTH. A FEW PASSING SHOWERS AND AN ISOLD THUNDERSTORM ARE POSSIBLE
BY THIS EVENING INTO TONIGHT...ALTHOUGH SINCE COVERAGE WILL BE
FAIRLY LIMITED...WE WILL LIMIT MENTION TO JUST VCSH FOR THE NORTHERN
TERMINALS OF KGFL/KALB/KPSF.
DUE TO THE CLOUDS AND A LIGHT SOUTHERLY BREEZE OVERNIGHT...NO FOG IS
ANTICIPATED AT KGFL/KALB. CLOUDS MAY BE THINNER AT KPSF/KPOU AND IF
WINDS LIGHTEN UP ENOUGH AFTER MIDNIGHT...THEN SOME BR/FG MAY BE
POSSIBLE. FOR NOW...WILL LIMIT TO JUST MVFR DUE TO THE UNCERTAINTY
ON TIMING/EXTENT AFTER ABOUT 07Z.
AFTER SUNRISE...ANY FOG SHOULD DISSIPATE AND VFR CONDITIONS WILL BE
IN PLACE FOR ALL TERMINALS. CLOUDS SHOULD SCT OUT FOR THE REMAINDER
OF THE MORNING AND EARLY AFTN...ALTHOUGH ADDITIONAL SHOWERS ARE
POSSIBLE LATER ON SUNDAY.
OUTLOOK...
SUN PM-THU...MAINLY VFR. CHC -TSRA/-SHRA MAINLY DURING THE AFTN
INTO THE EVNG.
&&
.FIRE WEATHER...
AS HIGHER LOWER LEVEL MOISTURE CONTINUES TO ADVECT INTO THE
REGION...OVERNIGHT DEW FORMATION ALONG WITH THE CHANCE FOR
ADDITIONAL SHOWERS AND THUNDERSTORMS WILL KEEP THE LOW LEVELS
RATHER MOIST THE NEXT FEW DAYS.
&&
.HYDROLOGY...
OVERALL...FLOWS WILL CONTINUE TO GRADUALLY LOWER CLOSER TO
SEASONAL NORMAL LEVELS OVER THE NEXT 5 DAYS.
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED
THROUGH EARLY NEXT WEEK...HOWEVER WIDESPREAD RAINFALL IS NOT
ANTICIPATED AT THIS TIME...AND NOT ALL LOCATIONS WILL RECEIVE THE
RAINFALL.
AS THE AIR MASS GETS MORE HUMID...SLOW MOVING THUNDERSTORMS COULD
PRODUCE A QUICK INCH OR SO OF RAINFALL WITH HIGHER THAN NORMAL
PWAT VALUES OVER THE HSA. SOME POOR DRAINAGE FLOODING OF LOW LYING
AREAS...AND PONDING OF WATER ON ROADWAYS WILL BE POSSIBLE ANY DAY.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...BGM
NEAR TERM...BGM
SHORT TERM...BGM
LONG TERM...HWJIV
AVIATION...FRUGIS
FIRE WEATHER...BGM
HYDROLOGY...BGM
FOR THE LATEST UPDATES...PLEASE VISIT OUR WEBPAGE AT
WWW.WEATHER.GOV/ALBANY
AREA FORECAST DISCUSSION
NWS MIAMI FL
137 PM EDT SAT JUN 22 2013
.AVIATION...RADAR SHOWS QUITE A BIT OF SHOWER ACTIVITY OVER THE NW
BAHAMAS AT THIS TIME. THERE HAS BEEN A FEW TSTORMS AS WELL. AS THE
TROUGH ASSOCIATED WITH THIS ACTIVITY MOVES WEST, WE EXPECT
SHOWERS TO MOVE INTO SE FLORIDA TONIGHT, ESPECIALLY AFTER
MIDNIGHT. A FEW THUNDERSTORMS WILL BE POSSIBLE AS WELL AS IT WILL
BE SUFFICIENTLY UNSTABLE ALONG WITH PWATS INCREASING TO AROUND 2
INCHES. GIVEN THESE FORECASTED TRENDS, HAVE ADDED VCTS TO ALL EAST
COAST TAF SITES BEGINNING AFTER MIDNIGHT AND CONTINUING THROUGH
SUNDAY. FOR KAPF, ACTIVITY IS EXPECTED TO REMAIN EAST OF THE
TERMINAL UNTIL AFTER ABOUT NOON ON SUNDAY, SO HELD OFF VCTS THERE
UNTIL 16Z SUNDAY. BRIEF IFR WILL BE POSSIBLE WHERE HEAVIER
SHRA/TSRA OCCURS, THOUGH PREVAILING CONDITIONS ARE EXPECTED TO
REMAIN VFR. THANKS FOR COLLABORATION CWSU MIAMI. /GREGORIA
&&
.PREV DISCUSSION... /ISSUED 1044 AM EDT SAT JUN 22 2013/
UPDATE...
FORECAST WAS UPDATED FOR THE SHORT TERM AND THE REMAINDER OF THE
WEEKEND. LATEST GUIDANCE SUGGESTS THAT FOR TODAY MAINLY ISOLATED
SHOWERS OR ISOLATED THUNDERSTORMS EXPECTED ACROSS THE ATLANTIC
WATERS AND EASTERN HALF OF THE PENINSULA WHILE FOR THE WESTERN
HALF THIS AFTERNOON MORE SCATTERED SHOWER AND THUNDERSTORM
ACTIVITY IS EXPECTED. THE FORECAST WAS ALSO UPDATED TO REFLECT A
CHANCE OF CONVECTION TONIGHT ACROSS THE ATLANTIC WATERS AND THE
EASTERN THIRD OF THE PENINSULA AS A LOW LEVEL TROUGH CONTINUES
TO MOVE WESTWARD ACROSS THE NORTHWEST BAHAMAS AND INTO THE LOCAL
ATLANTIC WATERS. THE LOW LEVEL TROUGH IS FORECAST TO REMAIN MOVING
WESTWARD ACROSS THE REGION TONIGHT THROUGH SUNDAY WITH A CHANCE
OF SHOWERS AND THUNDERSTORMS THROUGH THAT PERIOD.
60
PREV DISCUSSION... /ISSUED 648 AM EDT SAT JUN 22 2013/
AVIATION...
QUIET WEATHER IS EXPECTED FOR THE TAF PERIOD WITH VFR CONDITIONS
PREVAILING. THERE IS SOME TROPICAL MOISTURE TRYING TO MAKE ITS WAY
INTO SOUTH FLORIDA, BUT IS HAVING TROUBLE DUE TO THE DRY AIR IN
PLACE IN THE UPPER LEVELS. THERE IS STILL A SLIGHT CHANCE OF A
SHOWER OR A THUNDERSTORM TODAY, BUT TOO UNCERTAIN TO MAKE ANY
REFERENCE IN THE TAFS AT THIS TIME.
PREV DISCUSSION... /ISSUED 256 AM EDT SAT JUN 22 2013/
SHORT TERM (TODAY THROUGH MONDAY)...
DEEP LAYER RIDGE IS BEGINNING TO SHIFT NORTH AND THE 00Z MFL
SOUNDING WAS SHOWING A DEEP EASTERLY FLOW AT 5 TO 10 KNOTS. THE
TROPICAL WAVE THAT WAS PRODUCING NUMEROUS SHOWERS AND SOME
THUNDERSTORMS A FEW DAYS AGO HAS BEEN FIGHTING SOME DRY AIR THAT
SURROUNDS IT AND HAS NOW MOVED INTO THE CENTRAL CARIBBEAN LOSING MOST
OF ITS CONVECTION. THE NORTHERN PORTION OF THE WAVE HAS BECOME A
TROUGH OVER THE CENTRAL BAHAMAS AND HAS SCATTERED SHOWERS AND FEW
THUNDERSTORMS ASSOCIATED WITH IT. THE TROUGH HAS SLOWED ITS
FORWARD MOVEMENT AND MUCH DRIER AIR ALOFT IS AHEAD OF IT ACROSS
THE WESTERN BAHAMAS AND SOUTH FLORIDA. IN FACT, THE SOUNDING LAST
EVENING SHOWED THE PWAT HAD LOWERED TO 1.13 INCHES WHICH IS BELOW
THE 25TH PERCENTILE FOR MID-LATE JUNE AND THERE WERE ONLY A FEW
STORMS LATE YESTERDAY AS A RESULT OF THIS DRY AIR INTRUSION. DUE TO
THE FACT THE ACTUAL WAVE WILL NOW REMAIN WELL TO OUR SOUTH AND THE
TROUGH AXIS HAS SLOWED, THE HRRR IS SHOWING VIRTUALLY NO ACTION
ALONG THE EAST COAST TODAY AND WITH THE DEEP EAST TO WEST STEERING
FLOW DEPICTS SHOWERS AND STORMS DEVELOPING WELL INLAND AFTER 18Z
AND THEN INCREASING AS THEY MOVE TOWARDS THE COLLIER COUNTY COAST
AND THE LAKE REGION. THEREFORE, WILL LOWER THE POPS TO A SILENT 10
PERCENT OVER THE EAST METRO REGION AND TREND UP TO LOW END
SCATTERED FARTHER INLAND. ALL OF THE GLOBAL MODELS ARE IN GOOD
AGREEMENT WITH THIS SCENARIO AND ALSO INCREASE MOISTURE ON SUNDAY
AS THE TROUGH AXIS APPROACHES. THE MOISTURE WILL STILL BE AROUND
ON MONDAY BUT MODEL FORECAST SOUNDINGS ONLY SHOW AN INCREASE IN
PWAT TO NEAR AVERAGE FOR THIS TIME OF YEAR SO SIGNIFICANT RAINFALL
IS NOT ANTICIPATED.
LONG TERM (MONDAY NIGHT THROUGH FRIDAY)...
THE DEEP LAYER RIDGE WILL BECOME NEARLY STATIONARY ACROSS NORTH
FLORIDA FOR MUCH OF THE UPCOMING WEEK SO THE BEST CHANCES FOR RAIN
WILL BE DURING THE LATE NIGHT AND EARLY MORNING ALONG THE EAST
COAST AND IN THE AFTERNOON TO EARLY EVENING FOR THE INTERIOR AND
SOUTHWEST COAST. MOISTURE INCREASE WILL AGAIN NOT BE PLENTIFUL SO
ONLY ISOLATED AREAS OF HEAVIER RAIN CAN BE EXPECTED MAINLY WHERE
THE AFTERNOON THUNDERSTORMS CAN DEVELOP.
MARINE...
WIND SPEEDS WILL FLUCTUATE THROUGH THE PERIOD BUT REMAIN IN AN
EAST TO SOUTHEAST DIRECTION SO SEAS WILL BE AT 4 FEET OR LESS.
FIRE WEATHER...
NO PROBLEMS OR CONCERNS WITH AMPLE LOW LEVEL MOISTURE REMAINING IN PLACE.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 89 78 88 78 / 20 30 40 20
FORT LAUDERDALE 88 79 88 80 / 20 30 40 20
MIAMI 89 78 88 79 / 20 30 40 20
NAPLES 92 74 92 75 / 40 30 50 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MIAMI FL
1044 AM EDT SAT JUN 22 2013
.UPDATE...
FORECAST WAS UPDATED FOR THE SHORT TERM AND THE REMAINDER OF THE
WEEKEND. LATEST GUIDANCE SUGGESTS THAT FOR TODAY MAINLY ISOLATED
SHOWERS OR ISOLATED THUNDERSTORMS EXPECTED ACROSS THE ATLANTIC
WATERS AND EASTERN HALF OF THE PENINSULA WHILE FOR THE WESTERN
HALF THIS AFTERNOON MORE SCATTERED SHOWER AND THUNDERSTORM
ACTIVITY IS EXPECTED. THE FORECAST WAS ALSO UPDATED TO REFLECT A
CHANCE OF CONVECTION TONIGHT ACROSS THE ATLANTIC WATERS AND THE
EASTERN THIRD OF THE PENINSULA AS A LOW LEVEL TROUGH CONTINUES
TO MOVE WESTWARD ACROSS THE NORTHWEST BAHAMAS AND INTO THE LOCAL
ATLANTIC WATERS. THE LOW LEVEL TROUGH IS FORECAST TO REMAIN MOVING
WESTWARD ACROSS THE REGION TONIGHT THROUGH SUNDAY WITH A CHANCE
OF SHOWERS AND THUNDERSTORMS THROUGH THAT PERIOD.
60
&&
.PREV DISCUSSION... /ISSUED 648 AM EDT SAT JUN 22 2013/
AVIATION...
QUIET WEATHER IS EXPECTED FOR THE TAF PERIOD WITH VFR CONDITIONS
PREVAILING. THERE IS SOME TROPICAL MOISTURE TRYING TO MAKE ITS WAY
INTO SOUTH FLORIDA, BUT IS HAVING TROUBLE DUE TO THE DRY AIR IN
PLACE IN THE UPPER LEVELS. THERE IS STILL A SLIGHT CHANCE OF A
SHOWER OR A THUNDERSTORM TODAY, BUT TOO UNCERTAIN TO MAKE ANY
REFERENCE IN THE TAFS AT THIS TIME.
PREV DISCUSSION... /ISSUED 256 AM EDT SAT JUN 22 2013/
SHORT TERM (TODAY THROUGH MONDAY)...
DEEP LAYER RIDGE IS BEGINNING TO SHIFT NORTH AND THE 00Z MFL
SOUNDING WAS SHOWING A DEEP EASTERLY FLOW AT 5 TO 10 KNOTS. THE
TROPICAL WAVE THAT WAS PRODUCING NUMEROUS SHOWERS AND SOME
THUNDERSTORMS A FEW DAYS AGO HAS BEEN FIGHTING SOME DRY AIR THAT
SURROUNDS IT AND HAS NOW MOVED INTO THE CENTRAL CARIBBEAN LOSING MOST
OF ITS CONVECTION. THE NORTHERN PORTION OF THE WAVE HAS BECOME A
TROUGH OVER THE CENTRAL BAHAMAS AND HAS SCATTERED SHOWERS AND FEW
THUNDERSTORMS ASSOCIATED WITH IT. THE TROUGH HAS SLOWED ITS
FORWARD MOVEMENT AND MUCH DRIER AIR ALOFT IS AHEAD OF IT ACROSS
THE WESTERN BAHAMAS AND SOUTH FLORIDA. IN FACT, THE SOUNDING LAST
EVENING SHOWED THE PWAT HAD LOWERED TO 1.13 INCHES WHICH IS BELOW
THE 25TH PERCENTILE FOR MID-LATE JUNE AND THERE WERE ONLY A FEW
STORMS LATE YESTERDAY AS A RESULT OF THIS DRY AIR INTRUSION. DUE TO
THE FACT THE ACTUAL WAVE WILL NOW REMAIN WELL TO OUR SOUTH AND THE
TROUGH AXIS HAS SLOWED, THE HRRR IS SHOWING VIRTUALLY NO ACTION
ALONG THE EAST COAST TODAY AND WITH THE DEEP EAST TO WEST STEERING
FLOW DEPICTS SHOWERS AND STORMS DEVELOPING WELL INLAND AFTER 18Z
AND THEN INCREASING AS THEY MOVE TOWARDS THE COLLIER COUNTY COAST
AND THE LAKE REGION. THEREFORE, WILL LOWER THE POPS TO A SILENT 10
PERCENT OVER THE EAST METRO REGION AND TREND UP TO LOW END
SCATTERED FARTHER INLAND. ALL OF THE GLOBAL MODELS ARE IN GOOD
AGREEMENT WITH THIS SCENARIO AND ALSO INCREASE MOISTURE ON SUNDAY
AS THE TROUGH AXIS APPROACHES. THE MOISTURE WILL STILL BE AROUND
ON MONDAY BUT MODEL FORECAST SOUNDINGS ONLY SHOW AN INCREASE IN
PWAT TO NEAR AVERAGE FOR THIS TIME OF YEAR SO SIGNIFICANT RAINFALL
IS NOT ANTICIPATED.
LONG TERM (MONDAY NIGHT THROUGH FRIDAY)...
THE DEEP LAYER RIDGE WILL BECOME NEARLY STATIONARY ACROSS NORTH
FLORIDA FOR MUCH OF THE UPCOMING WEEK SO THE BEST CHANCES FOR RAIN
WILL BE DURING THE LATE NIGHT AND EARLY MORNING ALONG THE EAST
COAST AND IN THE AFTERNOON TO EARLY EVENING FOR THE INTERIOR AND
SOUTHWEST COAST. MOISTURE INCREASE WILL AGAIN NOT BE PLENTIFUL SO
ONLY ISOLATED AREAS OF HEAVIER RAIN CAN BE EXPECTED MAINLY WHERE
THE AFTERNOON THUNDERSTORMS CAN DEVELOP.
MARINE...
WIND SPEEDS WILL FLUCTUATE THROUGH THE PERIOD BUT REMAIN IN AN
EAST TO SOUTHEAST DIRECTION SO SEAS WILL BE AT 4 FEET OR LESS.
FIRE WEATHER...
NO PROBLEMS OR CONCERNS WITH AMPLE LOW LEVEL MOISTURE REMAINING IN PLACE.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 78 88 78 88 / 30 40 20 30
FORT LAUDERDALE 79 88 80 88 / 30 40 20 20
MIAMI 78 88 79 89 / 30 40 20 20
NAPLES 74 92 75 92 / 30 50 20 40
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...60/BD
AVIATION/RADAR...57/DG
AREA FORECAST DISCUSSION
NWS MIAMI FL
648 AM EDT SAT JUN 22 2013
.AVIATION...
QUIET WEATHER IS EXPECTED FOR THE TAF PERIOD WITH VFR CONDITIONS
PREVAILING. THERE IS SOME TROPICAL MOISTURE TRYING TO MAKE ITS WAY
INTO SOUTH FLORIDA, BUT IS HAVING TROUBLE DUE TO THE DRY AIR IN
PLACE IN THE UPPER LEVELS. THERE IS STILL A SLIGHT CHANCE OF A
SHOWER OR A THUNDERSTORM TODAY, BUT TOO UNCERTAIN TO MAKE ANY
REFERENCE IN THE TAFS AT THIS TIME.
&&
.PREV DISCUSSION... /ISSUED 256 AM EDT SAT JUN 22 2013/
SHORT TERM (TODAY THROUGH MONDAY)...
DEEP LAYER RIDGE IS BEGINNING TO SHIFT NORTH AND THE 00Z MFL
SOUNDING WAS SHOWING A DEEP EASTERLY FLOW AT 5 TO 10 KNOTS. THE
TROPICAL WAVE THAT WAS PRODUCING NUMEROUS SHOWERS AND SOME
THUNDERSTORMS A FEW DAYS AGO HAS BEEN FIGHTING SOME DRY AIR THAT
SURROUNDS IT AND HAS NOW MOVED INTO THE CENTRAL CARIBBEAN LOSING MOST
OF ITS CONVECTION. THE NORTHERN PORTION OF THE WAVE HAS BECOME A
TROUGH OVER THE CENTRAL BAHAMAS AND HAS SCATTERED SHOWERS AND FEW
THUNDERSTORMS ASSOCIATED WITH IT. THE TROUGH HAS SLOWED ITS
FORWARD MOVEMENT AND MUCH DRIER AIR ALOFT IS AHEAD OF IT ACROSS
THE WESTERN BAHAMAS AND SOUTH FLORIDA. IN FACT, THE SOUNDING LAST
EVENING SHOWED THE PWAT HAD LOWERED TO 1.13 INCHES WHICH IS BELOW
THE 25TH PERCENTILE FOR MID-LATE JUNE AND THERE WERE ONLY A FEW
STORMS LATE YESTERDAY AS A RESULT OF THIS DRY AIR INTRUSION. DUE TO
THE FACT THE ACTUAL WAVE WILL NOW REMAIN WELL TO OUR SOUTH AND THE
TROUGH AXIS HAS SLOWED, THE HRRR IS SHOWING VIRTUALLY NO ACTION
ALONG THE EAST COAST TODAY AND WITH THE DEEP EAST TO WEST STEERING
FLOW DEPICTS SHOWERS AND STORMS DEVELOPING WELL INLAND AFTER 18Z
AND THEN INCREASING AS THEY MOVE TOWARDS THE COLLIER COUNTY COAST
AND THE LAKE REGION. THEREFORE, WILL LOWER THE POPS TO A SILENT 10
PERCENT OVER THE EAST METRO REGION AND TREND UP TO LOW END
SCATTERED FARTHER INLAND. ALL OF THE GLOBAL MODELS ARE IN GOOD
AGREEMENT WITH THIS SCENARIO AND ALSO INCREASE MOISTURE ON SUNDAY
AS THE TROUGH AXIS APPROACHES. THE MOISTURE WILL STILL BE AROUND
ON MONDAY BUT MODEL FORECAST SOUNDINGS ONLY SHOW AN INCREASE IN
PWAT TO NEAR AVERAGE FOR THIS TIME OF YEAR SO SIGNIFICANT RAINFALL
IS NOT ANTICIPATED.
LONG TERM (MONDAY NIGHT THROUGH FRIDAY)...
THE DEEP LAYER RIDGE WILL BECOME NEARLY STATIONARY ACROSS NORTH
FLORIDA FOR MUCH OF THE UPCOMING WEEK SO THE BEST CHANCES FOR RAIN
WILL BE DURING THE LATE NIGHT AND EARLY MORNING ALONG THE EAST
COAST AND IN THE AFTERNOON TO EARLY EVENING FOR THE INTERIOR AND
SOUTHWEST COAST. MOISTURE INCREASE WILL AGAIN NOT BE PLENTIFUL SO
ONLY ISOLATED AREAS OF HEAVIER RAIN CAN BE EXPECTED MAINLY WHERE
THE AFTERNOON THUNDERSTORMS CAN DEVELOP.
MARINE...
WIND SPEEDS WILL FLUCTUATE THROUGH THE PERIOD BUT REMAIN IN AN
EAST TO SOUTHEAST DIRECTION SO SEAS WILL BE AT 4 FEET OR LESS.
FIRE WEATHER...
NO PROBLEMS OR CONCERNS WITH AMPLE LOW LEVEL MOISTURE REMAINING IN PLACE.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 89 78 88 78 / 10 20 20 20
FORT LAUDERDALE 88 79 88 80 / 10 20 20 20
MIAMI 89 78 88 79 / 10 20 20 20
NAPLES 92 74 92 75 / 30 20 20 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...30/KOB
AVIATION/RADAR...13/SI
AREA FORECAST DISCUSSION
NWS MIAMI FL
256 AM EDT SAT JUN 22 2013
.SHORT TERM (TODAY THROUGH MONDAY)...
DEEP LAYER RIDGE IS BEGINNING TO SHIFT NORTH AND THE 00Z MFL
SOUNDING WAS SHOWING A DEEP EASTERLY FLOW AT 5 TO 10 KNOTS. THE
TROPICAL WAVE THAT WAS PRODUCING NUMEROUS SHOWERS AND SOME
THUNDERSTORMS A FEW DAYS AGO HAS BEEN FIGHTING SOME DRY AIR THAT
SURROUNDS IT AND HAS NOW MOVED INTO THE CENTRAL CARIBBEAN LOSING MOST
OF ITS CONVECTION. THE NORTHERN PORTION OF THE WAVE HAS BECOME A
TROUGH OVER THE CENTRAL BAHAMAS AND HAS SCATTERED SHOWERS AND FEW
THUNDERSTORMS ASSOCIATED WITH IT. THE TROUGH HAS SLOWED ITS
FORWARD MOVEMENT AND MUCH DRIER AIR ALOFT IS AHEAD OF IT ACROSS
THE WESTERN BAHAMAS AND SOUTH FLORIDA. IN FACT, THE SOUNDING LAST
EVENING SHOWED THE PWAT HAD LOWERED TO 1.13 INCHES WHICH IS BELOW
THE 25TH PERCENTILE FOR MID-LATE JUNE AND THERE WERE ONLY A FEW
STORMS LATE YESTERDAY AS A RESULT OF THIS DRY AIR INTRUSION. DUE TO
THE FACT THE ACTUAL WAVE WILL NOW REMAIN WELL TO OUR SOUTH AND THE
TROUGH AXIS HAS SLOWED, THE HRRR IS SHOWING VIRTUALLY NO ACTION
ALONG THE EAST COAST TODAY AND WITH THE DEEP EAST TO WEST STEERING
FLOW DEPICTS SHOWERS AND STORMS DEVELOPING WELL INLAND AFTER 18Z
AND THEN INCREASING AS THEY MOVE TOWARDS THE COLLIER COUNTY COAST
AND THE LAKE REGION. THEREFORE, WILL LOWER THE POPS TO A SILENT 10
PERCENT OVER THE EAST METRO REGION AND TREND UP TO LOW END
SCATTERED FARTHER INLAND. ALL OF THE GLOBAL MODELS ARE IN GOOD
AGREEMENT WITH THIS SCENARIO AND ALSO INCREASE MOISTURE ON SUNDAY
AS THE TROUGH AXIS APPROACHES. THE MOISTURE WILL STILL BE AROUND
ON MONDAY BUT MODEL FORECAST SOUNDINGS ONLY SHOW AN INCREASE IN
PWAT TO NEAR AVERAGE FOR THIS TIME OF YEAR SO SIGNIFICANT RAINFALL
IS NOT ANTICIPATED.
.LONG TERM (MONDAY NIGHT THROUGH FRIDAY)...
THE DEEP LAYER RIDGE WILL BECOME NEARLY STATIONARY ACROSS NORTH
FLORIDA FOR MUCH OF THE UPCOMING WEEK SO THE BEST CHANCES FOR RAIN
WILL BE DURING THE LATE NIGHT AND EARLY MORNING ALONG THE EAST
COAST AND IN THE AFTERNOON TO EARLY EVENING FOR THE INTERIOR AND
SOUTHWEST COAST. MOISTURE INCREASE WILL AGAIN NOT BE PLENTIFUL SO
ONLY ISOLATED AREAS OF HEAVIER RAIN CAN BE EXPECTED MAINLY WHERE
THE AFTERNOON THUNDERSTORMS CAN DEVELOP.
&&
.AVIATION...
QUIET WEATHER IS EXPECTED FOR THE TAF PERIOD WITH VFR CONDITIONS
PREVAILING. THERE IS SOME TROPICAL MOISTURE TRYING TO MAKE ITS WAY
INTO SOUTH FLORIDA, BUT IS HAVING TROUBLE DUE TO THE DRY AIR IN
PLACE IN THE UPPER LEVELS. THERE IS STILL A VERY SLIGHT CHANCE OF
A SHOWER OR A THUNDERSTORM TODAY, BUT TOO UNCERTAIN TO MAKE ANY
REFERENCE IN THE TAFS AT THIS TIME.
&&
.MARINE...
WIND SPEEDS WILL FLUCTUATE THROUGH THE PERIOD BUT REMAIN IN AN
EAST TO SOUTHEAST DIRECTION SO SEAS WILL BE AT 4 FEET OR LESS.
&&
.FIRE WEATHER...
NO PROBLEMS OR CONCERNS WITH AMPLE LOW LEVEL MOISTURE REMAINING IN PLACE.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 89 78 88 78 / 10 20 20 20
FORT LAUDERDALE 88 79 88 80 / 10 20 20 20
MIAMI 89 78 88 79 / 10 20 20 20
NAPLES 92 74 92 75 / 30 20 20 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...30/KOB
AVIATION/RADAR...13/SI
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1024 PM CDT SUN JUN 23 2013
.DISCUSSION...
723 PM CDT
MADE MINOR TWEAKS TO THE GOING FORECAST. CONVECTION HAS SUBSIDED
WITH SHOWERS FROM CHICAGO THROUGH STREATOR. EXPECTING THE SHOWERS
TO SLOWLY WEAKEN AND MOVE EASTWARD...PRODUCING UP TO AN ADDITIONAL
TENTH OF AN INCH OF PRECIP. THE CONVECTIVE OUTFLOW COOLED AREAS
BUT MOST PLACES HAVE REBOUNDED...SO ADJUSTED TEMPS TRENDS BUT DID
NOT MAKE MAJOR CHANGES TO LOW TEMPS TONIGHT.
AS FAR AS PRECIP CHANCES THROUGH THE REST OF THE NIGHT...MADE
MINOR ADJUSTMENTS BUT THE OVERALL PICTURE REMAINS THE SAME.
EXPECTING CONVECTION TO REFIRE IN THE FOUR CORNERS AREA OF
NE/IA/MO/KS AND SPREAD ACROSS IA OVERNIGHT. STEERING FLOW WOULD
DIRECT THE STORMS TO THE EAST WITH STORMS ENTERING AREAS ALONG AND
WEST OF THE I-39 CORRIDOR AROUND/AFTER 09Z. HOWEVER CONFIDENCE IS
LOW TO MEDIUM IN HOW CONVECTION WILL EVOLVE AND LOW IN TIMING.
HEAVY RAIN IS A DEFINITE CONCERN...BUT DUE TO LOW CONFIDENCE IN
THE CONVECTIVE EVOLUTION I WILL HOLD OFF ISSUING A FLASH FLOOD
WATCH. LIGHTNING...GUSTY WINDS...AND SMALL HAIL ARE ALSO
POSSIBLE...BUT THINKING SEVERE WEATHER WILL BE ISOLATED AT BEST
DUE TO THE ELEVATED NATURE OF THE STORMS.
JEE
//PREV DISCUSSION...
304 PM CDT
SHOWER/THUNDER CHANCES REMAIN THE BIGGEST FORECAST CHALLENGE
FOLLOWED BY TEMPS WHICH MAY BE AFFECTED BY THE CONVECTION. AFTERNOON
WATER VAPOR IMAGERY SHOWS ONE UPPER LEVEL LOW SPINNING OVER THE
CENTRAL APPALACHIANS WHICH IS LOSING DEFINITION AS IS MOVES SLOWLY
NORTHWARD. THE NEXT UPPER LOW IS SPINNING OVER THE SOUTHERN
CANADIAN PRAIRIES WITH A TROUGH AXIS EXTENDING INTO THE DAKOTAS AND
LIFTING NORTHEAST. THE UPPER FLOW IS LESS AMPLIFIED FURTHER SOUTH OF
THE LOW ACROSS THE CENTRAL PLAINS BUT THERE ARE SEVERAL EMBEDDED
WAVES THAT ARE TRANSLATING NORTHEAST AS WELL. THE NEXT UPPER LOW OF
NOTE IS COMING ONSHORE OVER THE WEST COAST AND HELPING TO AMPLIFY A
RIDGE OVER OREGON/WASHINGTON. ENERGY EMANATING FROM THIS TROUGH WILL
BECOME A PLAYER IN OUR WEATHER LATER THIS WEEK. AT THE SURFACE...LOW
PRESSURE IS POSITIONED OVER NORTHWEST MINNESOTA WITH WEAKER LOW
PRESSURE SPREAD ACROSS THE PLAINS. A COOL FRONTAL BOUNDARY IS
STRETCHED FROM THE MN LOW BUT HAS BECOME DIFFICULT TO IDENTIFY
THANKS TO COLD POOLS FROM MORNING CONVECTION.
THROUGH THIS EVENING...TOUGH FORECAST ONCE AGAIN IN TERMS OF
CONVECTIVE POTENTIAL AND EVOLUTION THROUGH THE PERIOD. OUTFLOW
BOUNDARY FROM EARLIER IOWA CONVECTION IS NOW PUSHING INTO THE
WESTERN CWA TRIGGERING THUNDERSTORMS ALONG IT. A BETTER ORGANIZED
COMPLEX OF STORMS HAS DEVELOPED FROM THE EARLIER CONVECTION BUT IS
MOVING SOUTHEAST ACROSS NORTHERN MISSOURI INTO THE AXIS OF MUCH
BETTER INSTABILITY AS WELL AS BETTER MID LEVEL MOISTURE
ADVECTION. ADDITIONAL SCATTERED STORMS HAVE DEVELOPED OVER THE
SOUTHERN CWA LIKELY IN BETTER CONJUNCTION WITH THE WEAKENING UPPER
LOW OVER APPALACHIA. IN THE NEAR TERM...EXPECT THE OUTFLOW TO
CONTINUE EASTWARD ACROSS THE CWA TRIGGERING SCATTERED STORMS THROUGH
LATE AFTERNOON/EARLY EVENING. MESOANALYSIS SHOWS 2000+ J/KG OF MIXED
LAYER CAPE OVER THE AREA SUPPORTING STRONG UPDRAFTS BUT DEEP LAYER
SHEAR IS WEAK SO CORES SHOULD BE PRETTY PULSEY. LARGE HAIL AND
LOCALLY HEAVY DOWNPOURS ARE THE MAIN CONCERN. GUSTY WINDS ARE ALSO
POSSIBLE BUT RECENT AIRCRAFT SOUNDINGS FROM MDW DO NOT SHOW A TON OF
DRY LOW LEVEL AIR AND RAP ANALYSIS OF DCAPE IS LOW AS WELL. WOULD
EXPECT THAT THIS ACTIVITY WOULD WANE WITH SUNSET.
REST OF TONIGHT AND MONDAY...ATTENTION TURNS TO ADDITIONAL
CONVECTIVE POTENTIAL OVERNIGHT. WATER VAPOR SHOWS A WAVE OVER NE
KS/NW MO WHICH APPEARS TO BE TURNING MORE EASTWARD IN THE LAST FEW
SCANS. THIS IS LIKELY HELPING THE COMPLEX TAKING SHAPE OVER MO.
SHORT TERM/HIGH RES GUIDANCE HAS BEEN ALL OVER THE PLACE WITH HOW
CONVECTION EVOLVES THROUGH TONIGHT. THE MOIST SOUTHWESTERLY FLOW
WILL CONTINUE ACROSS THE REGION TONIGHT AND THE EARLIER COLD FRONTAL
BOUNDARY SEEMS TO BE DEVELOPING ONCE AGAIN ACROSS IOWA AS THE FLOW
HAS SETTLED FROM EARLIER CONVECTION. THIS IS SUPPORTIVE OF NEW
DEVELOPMENT TO THE WEST TONIGHT. THE OUTFLOW CURRENTLY WORKING INTO
THE LOCAL AREA EXTENDS INTO WEST-CENTRAL ILLINOIS AND THERE ARE
HINTS THAT THE SOUTHERN EXTENT OF IT AND LIKELY A BOUNDARY SET UP BY
THE CURRENT COMPLEX MAY STALL OUT SOMEWHERE NOT FAR FROM THE
SOUTHWESTERN CWA. IN ADDITION...THE KS/MO WAVE IS EXPECTED TO CROSS
THIS SAME AREA TONIGHT WHICH IS ALSO EXPECTED TO BE IN AN AREA OF
MID LEVEL WARM ADVECTION. THEREFORE IT IS POSSIBLE ROUNDS OF
CONVECTION COULD DEVELOP TO THE SOUTHWEST OF THE AREA AND ROLL
EASTWARD INTO THE SOUTHERN CWA OVERNIGHT. HAVE NOT MADE MUCH CHANGE
TO OVERNIGHT POPS BUT DID INCREASE THEM SOMEWHAT OVER THE FAR SOUTH.
AS FOR MONDAY...GUIDANCE REMAINS IN POOR AGREEMENT WITH TRACK OF
POTENTIAL UPPER WAVES BUT WATER VAPOR DOES SHOW SOME SIGNS OF A WAVE
COMING ACROSS THE FOUR CORNERS THIS AFTERNOON. THIS WOULD COME ACROSS
THE REGION LATER MONDAY BUT IT IS NOT CLEAR IF IT WILL BE MORE
FOCUSED TO THE NORTH OF THE AREA. WILL CONTINUE WITH MID CHANCE POPS
WITH LATER IN THE DAY MORE FAVORED. PROVIDED THE LATER TIMING WORKS
OUT THEN WE WILL HAVE A BETTER CHANCE TO WARM BUT THERE MAY BE
CONVECTIVE DEBRIS AROUND SO WILL HOLD TEMPS INTO THE MID 80S FOR
MOST AREAS.
TUESDAY THROUGH SUNDAY...THE UPPER FLOW BECOMES LESS AMPLIFIED
TUESDAY BUT WILL LIKELY STILL BE LITTERED WITH WAVES TRAVERSING IT.
HOT AND HUMID AIR WILL STILL BE IN PLACE WITH PRECIPITABLE WATER
VALUES HOVERING AROUND 1.75 INCHES. THESE FACTORS PROVIDE CONTINUED
SUPPORT FOR THUNDERSTORM DEVELOPMENT BUT THERE IS NOT MUCH TO KEY IN
ON FOR A COHERENT FORCING MECHANISM GIVEN THE LOW AMPLITUDE PATTERN.
BY WEDNESDAY...THERE IS SOME AGREEMENT ON SURFACE LOW PRESSURE
HAVING DEVELOPED ACROSS THE CANADIAN PRAIRIES WITH A TROUGH
AXIS/FRONT EXTENDING INTO MINNESOTA AND IOWA...WITH A SECONDARY LOW
POSSIBLY DEVELOPING ACROSS MINNESOTA. THE FRONT LOOKS TO CROSS THE
AREA LATER WEDNESDAY BRINGING SHOWER AND STORM CHANCES WITH IT.
UPPER RIDGING WILL BE BUILDING ACROSS THE WESTERN U.S. AND HIGH
PLAINS WITH A WAVE ORIGINATING FROM THE TROUGH OFF THE WEST COAST
OVERTOPPING THE RIDGE ACROSS THE CANADIAN ROCKIES AND DROPPING
SOUTHEASTWARD INTO THE GREAT LAKES WHILE AMPLIFYING LATE IN THE
WEEK. GFS AND ECMWF DIFFER ON HOW QUICKLY THIS OCCURS BUT THE SIGNAL
HAS BEEN CONSISTENT OVERALL. THIS WILL BRING A SHIFT TO
NORTHWESTERLY AT THE SURFACE AND ALOFT LATE IN THE WEEK AND
NOTICEABLY COOLER TEMPERATURES BY SATURDAY OR SO. LOW POPS WILL
CONTINUE WITH THE FLOW CONTINUING TO FAVOR WEAK SHORTWAVE PASSAGES.
HIGH TEMPS WILL LIKELY HOVER AROUND 90 TUESDAY AND WEDNESDAY
ASSUMING CONVECTION OR CONVECTIVE DEBRIS IS NOT AN ISSUE...WHICH
WOULD SIGNIFICANTLY LOWER HIGHS IF IT IS. WITH THE PASSAGE OF THE
SYSTEM LATER WEDNESDAY COOLER MID LEVEL AIR WILL FILTER IN KEEPING
HIGHS BACK IN THE 80S WITH UPPER 70S POSSIBLE FRIDAY AND SATURDAY.
MDB
&&
.HYDROLOGY...
745 PM CDT
THE CONVECTIVE ACTIVITY THIS EVENING PRODUCED ISOLATED AREAS OF 2+
INCHES OF RAIN AND A BAND OF 1+ INCHES OF RAIN ACROSS LA SALLE
COUNTY. STILL CONSIDERED A FLASH FLOOD WATCH FOR THE WEST AND FAR
SOUTHWEST CWA GIVEN THE RAINFALL OF THE PAST FEW DAYS. CONFIDENCE
REMAINS LOW IN WHERE ORGANIZED CONVECTION WILL SET UP TONIGHT AND
MONDAY SO WILL HOLD OFF UNTIL AREAS AND TIMING CAN BE BETTER
DEFINED.
JEE/MDB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* CHANCE OF SHRA/TSRA MONDAY MORNING AND AGAIN MONDAY AFTERNOON.
* POSSIBLE GUSTY SOUTHWESTERLY WINDS MONDAY. CMS
//DISCUSSION...UPDATED 00Z...
THUNDERSTORMS HAVE HAVE SHOWN A RAPID DIMINISHING TREND OVER THE
LAST HOUR AND EXPECT THIS TO CONTINUE WITH ONLY SHOWERS EXPECTED.
AFTER THESE SHOWERS DIMINISH...DO EXPECT A DRY PERIOD FOR THE
REMAINDER OF THE EVENING BEFORE CHANCES FOR SHOWERS/THUNDERSTORMS
BEGIN TO INCREASE ONCE AGAIN EARLY MONDAY MORNING. SEVERAL CHANCES
FOR SHOWERS AND THUNDERSTORMS DO APPEAR POSSIBLE THROUGHOUT THE
DAY ON MONDAY...BUT WITH CONFIDENCE LOWER ON EXACT TIMING.
ALTHOUGH...MONDAY AFTERNOON APPEARS AS IF IT COULD BE AN ACTIVE
PERIOD. OUTSIDE OF THE THE PRECIP CHANCES THIS FORECAST PERIOD AND
MAYBE SOME PATCHY FOG EARLY MONDAY MORNING...EXPECT VFR CONDITIONS
WITH SOUTH/SOUTHWEST WINDS IN PLACE.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* LOW REGARDING PRECIP POTENTIAL MONDAY MORNING...MEDIUM FOR
MONDAY AFTERNOON.
* MEDIUM FOR WIND SPEEDS/GUSTS THROUGH THE PERIOD. CMS
//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...
TUESDAY THROUGH FRIDAY...PERIODIC CHANCES OF TSRA.
SATURDAY...CHANCE OF SHRA.
RODRIGUEZ
&&
.MARINE...
420 PM CDT
A LARGE AREA OF HIGH PRESSURE EXTENDS FROM THE WESTERN ATLANTIC
SOUTHWESTWARD ACROSS THE SOUTHEASTERN U.S. AND THE NORTHERN GULF
OF MEXICO. THIS HIGH WILL BE MOVING ONLY VERY SLOWLY SOUTHEASTWARD
TONIGHT THROUGH THURSDAY. LOW PRESSURE NEAR LAKE WINNIPEG WILL BE
MOVING SLOWLY EASTWARD ACROSS ONTARIO...REACHING NEAR SOUTHERN JAMES
BAY BY TUESDAY MORNING. THEN...AN AREA OF LOW PRESSURE STRETCHING
FROM THE SOUTHERN CANADIAN PRAIRIE SOUTH ACROSS THE PLAINS WILL MOVE
NORTHEAST DURING TUESDAY AND WEDNESDAY. WITH HIGH PRESSURE SITUATED
FAR TO THE SOUTH THROUGH SOUTHEAST OF THE LAKE AND LOW PRESSURE FROM
FAR WEST THROUGH NORTHWEST TONIGHT INTO THURSDAY...MODERATE TO FRESH
WINDS WILL PERSIST OUT OF THE SOUTH TO SOUTHWEST.
THIS PERSISTENT FLOW WILL KEEP VERY MOIST AIR ACROSS THE WESTERN
GREAT LAKES REGION. WHILE MOST OF THE FOG HAD DISSIPATED ON NORTHERN
LAKE MICHIGAN...WITH THE MOIST AIR AND COOL LAKE WATER FOG IS
EXPECTED TO REDEVELOP TONIGHT AND BECOME DENSE IN AREAS. THE CURRENT
DENSE FOG ADVISORY FOR NORTHERN LAKE MICHIGAN WILL LIKELY NEED TO BE
EXTENDED INTO TUESDAY AND POSSIBLY WEDNESDAY AS THERE WILL BE NO
CHANGE IN AIRMASS UNTIL A COLD FRONT PUSHES ACROSS THE LAKE DURING
LATER WEDNESDAY AND WEDNESDAY NIGHT...SHIFTING WINDS TO OUT OF THE
WEST. A SECONDARY COLD FRONT WILL MOVE ACROSS THE LAKE AND SHIFT
WINDS TO OUT OF THE NORTHWEST DURING LATER THURSDAY AND THURSDAY
NIGHT.
TRS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565
UNTIL 7 AM MONDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS LINCOLN IL
753 PM CDT SUN JUN 23 2013
.DISCUSSION...
ISSUED 747 PM CDT SUN JUN 23 2013
DROPPED THE OVERNIGHT LOWS A COUPLE DEGREES FROM TODAYS
PRECIP...WITH NOT TOO FAR TO GO FOR SOME LOCATIONS THANKS TO
ONGOING PRECIP. SOME MINOR TWEAKS TO THE FORECAST IN REGARDS TO
POPS BEFORE MIDNIGHT...REFLECTING THE EVOLUTION OF THE DYING
PRECIP THAT IS OUT THERE NOW. HOWEVER...MODELS IN THE SHORT TERM
STILL QUITE POLARIZED. WITH THAT IN MIND...AND A COUPLE OF
DISCRETE CELLS IN NRN MO...KEEPING THE LIKELY POPS FOR AFTER
MIDNIGHT IN THE NW. REMAIN IN ACTIVE AND ERRATIC PATTERN THROUGH
THE OVERNIGHT. MANY OUTFLOW BOUNDARIES AND INTERACTIONS IN A
RELATIVELY STABLE AIRMASS...ANY CONCERN FOR SEVERE WEATHER AT THIS
POINT IS FOCUSED MAINLY ON FLOODING POTENTIAL IN THE SOUTHEAST.
UPDATE OUT MOMENTARILY.
HJS
&&
.AVIATION...
ISSUED 658 PM CDT SUN JUN 23 2013
ADJUSTING FORECAST IN THE SHORT TERM TO HANDLE THE SLOWLY
DWINDLING CONVECTION. PRECIP FALLING APART A BIT QUICKER THAN PREV
MODEL RUNS ANTICIPATED...AND AS A RESULT HAVE LEFT TOO MUCH
MENTION OF PRECIP IN MOST OF THE TAFS. CONCERN FOR PRECIP
CONTINUES THROUGH TOMORROW THOUGH MODELS ARE ALL OVER THE PLACE.
MOST FAITH IN HRRR FOR NOW...WHICH HAS A MORE SCT SIGNATURE. WILL
AWAIT NEXT RUN BEFORE CALLING PRECIP AND TIMING FOR TOMORROW.
HJS
&&
.PREV DISCUSSION...
ISSUED 300 PM CDT SUN JUN 23 2013
TWO ONGOING COMPLEXES OF STORMS WILL HIGHLIGHT THE SHORT
TERM...A LINE OF STORMS IN THE NW AND A CLUSTER OF HEAVY RAIN IN
THE SE. HEAT AND PERIODIC STORM CHANCES WILL CONTINUE FOR MUCH OF
THE WEEK UNTIL A MORE SIGNIFICANT UPPER WAVE MAKES PROGRESS FROM
CANADA ACROSS THE GREAT LAKES AND CHANGES OUR UPPER FLOW OUT OF
THE NORTHWEST...AS A TROUGH DEVELOPS IN THE EAST AND A RIDGE TO
OUR WEST.
SHORT TERM...TONIGHT THROUGH THURSDAY.
THE HEAVY RAIN COMPLEX IN THE SOUTHEAST ASSOCIATED WITH A MESO-
VORTEX APPEARS TO BE WEAKENING...ALBEIT WITH STEADY RAINS
CONTINUING ACROSS A WATER-LOGGED AREA. SEVERAL FLASH FLOOD
WARNINGS REMAIN IN EFFECT INTO THIS EVENING FOR THAT AREA...WHERE
3-5 INCHES OF RAIN HAS FALLEN. SPC MESO-ANALYSIS GRAPHICS SHOW
INSTABILITY PARAMETERS IN THE SE AREA APPEAR TO BE
STABILIZING...WHILE BETTER SUPPORT FOR STRONG STORMS EXISTS AHEAD
OF THE LINE OF STORMS ENTERING OUR NW COUNTIES. ML-CAPE VALUES OF
3000-3500 J/KG SHOULD BE ENOUGH TO KEEP THEM ADVANCING INTO OUR
AREA. PRECIPITABLE WATER VALUES AROUND 1.7" AND VERY WEAK WINDS IN
THE MID-UPPER LEVELS LEND SUPPORT FOR HEAVY RAIN FROM THOSE STORMS
INTO THIS EVENING. THEY SHOULD MAINTAIN BETTER FORWARD PROGRESS
BASED ON THE MOVEMENT OF THE UPPER SHORTWAVE ON WATER VAPOR
SATELLITE. THE TRACK OF THE LINE OF STORMS SHOULD EVENTUALLY BEGIN
TO CURL TO THE SOUTHEAST. WE TRIED TO MATCH POPS TO CURRENT
CONDITIONS AND PROGRESS THEM THROUGH THE EVENING AND OVERNIGHT
UTILIZING SATELLITE AND RADAR TRENDS. MODELS HAVE GENERALLY BEEN
ALL OVER THE PLACE WITH CONVECTIVE SOLUTIONS...SO THEY HAVE NOT
BEEN MUCH HELP TO FORECAST DETAILS IN THE NEAR TERM.
WE USED GENERAL MODEL TRENDS WITH THE PROGRESS OF THE OVERALL
PATTERN THROUGH MID WEEK. WE EXPECT TO REMAIN IN THE WARM SECTOR
THROUGH THURSDAY...A GRADUAL BUILDING OF THE UPPER LEVEL RIDGE
INTO CENTRAL IL FOR TUESDAY AND TUESDAY NIGHT...WHICH MAY HELP
SUPPRESS STORMS FOR AROUND 24 HOURS. WE KEPT SLIGHT CHANCE POPS
TUE-TUE NIGHT AS A RESULT. UPPER TROUGHING REDEVELOPS FOR
WEDNESDAY AS A SURFACE TROUGH PROGRESSES ACROSS IL WED NIGHT
INTO THURSDAY. THAT WILL INITIALLY ESTABLISH NORTHWEST FLOW
ALOFT...AND BEGIN OUR AIRMASS CHANGE THAT IS PROJECTED TO FINALLY
BECOME ESTABLISHED NEXT WEEKEND.
IN THE MEAN TIME...TUESDAY AND WEDNESDAY LOOK TO BE OUR HOTTEST
DAYS OF THIS WEEK...AS HEAT INDEX READINGS CLIMB INTO THE 100-105
RANGE EACH AFTERNOON AND EARLY EVENING...OUTSIDE OF ANY STORM
COMPLEXES.
WE INCREASED POPS INTO THE CHANCE CATEGORY FOR WED AFTERNOON AND
CONTINUED CHANCE POPS WED NIGHT...CONFINING THEM TO THE EASTERN
AREAS ON THURSDAY AS THE TROUGH PUSHES EAST INTO INDIANA. WE MAY
SEE ANOTHER ROUND OF STRONG STORMS WITH HEAVY RAIN ALONG THAT
FRONT...AS PLENTY OF MOISTURE POOLING IS PROJECTED TO OCCUR AHEAD
OF THE SYSTEM.
LONG TERM...FRIDAY THROUGH SUNDAY.
A COOLING TREND SHOULD ALREADY BE NOTICEABLE ON FRIDAY AS SURFACE
WINDS TURN OUT OF THE NORTHWEST AND DEWPOINTS BEGIN TO DROP FROM
THE 70S INTO THE 60S. WE HELD ONTO A SLIGHT CHANCE OF SHOWERS AND
STORMS ON FRIDAY...AS THE UPPER TROUGH AXIS DEPARTS EASTWARD AND A
500MB SHORTWAVE ROTATES THROUGH THE BACK SIDE OF THE TROUGH. THE
DAY SHOULD BE DOMINATED BY CLOUDS HELPING TO KEEP HIGHS IN THE MID
80S. DRY CONDITIONS SHOULD RETURN FRI NIGHT...WITH A FEW
INSTABILITY SHOWERS POSSIBLE IN THE EAST ON SATURDAY AS THE COLD
POOL ALOFT PASSES OVER THE AREA. HIGHS ON SATURDAY AND SUNDAY
SHOULD TOP OUT IN THE LOWER 80S WITH OVERNIGHT LOWS IN THE LOW
60S...WITH MUCH LESS HUMIDITY IN THE AIR.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
746 PM CDT SUN JUN 23 2013
.DISCUSSION...
723 PM CDT
MADE MINOR TWEAKS TO THE GOING FORECAST. CONVECTION HAS SUBSIDED
WITH SHOWERS FROM CHICAGO THROUGH STREATOR. EXPECTING THE SHOWERS
TO SLOWLY WEAKEN AND MOVE EASTWARD...PRODUCING UP TO AN ADDITIONAL
TENTH OF AN INCH OF PRECIP. THE CONVECTIVE OUTFLOW COOLED AREAS
BUT MOST PLACES HAVE REBOUNDED...SO ADJUSTED TEMPS TRENDS BUT DID
NOT MAKE MAJOR CHANGES TO LOW TEMPS TONIGHT.
AS FAR AS PRECIP CHANCES THROUGH THE REST OF THE NIGHT...MADE
MINOR ADJUSTMENTS BUT THE OVERALL PICTURE REMAINS THE SAME.
EXPECTING CONVECTION TO REFIRE IN THE FOUR CORNERS AREA OF
NE/IA/MO/KS AND SPREAD ACROSS IA OVERNIGHT. STEERING FLOW WOULD
DIRECT THE STORMS TO THE EAST WITH STORMS ENTERING AREAS ALONG AND
WEST OF THE I-39 CORRIDOR AROUND/AFTER 09Z. HOWEVER CONFIDENCE IS
LOW TO MEDIUM IN HOW CONVECTION WILL EVOLVE AND LOW IN TIMING.
HEAVY RAIN IS A DEFINITE CONCERN...BUT DUE TO LOW CONFIDENCE IN
THE CONVECTIVE EVOLUTION I WILL HOLD OFF ISSUING A FLASH FLOOD
WATCH. LIGHTNING...GUSTY WINDS...AND SMALL HAIL ARE ALSO
POSSIBLE...BUT THINKING SEVERE WEATHER WILL BE ISOLATED AT BEST
DUE TO THE ELEVATED NATURE OF THE STORMS.
JEE
&&
.PREV DISCUSSION...
304 PM CDT
SHOWER/THUNDER CHANCES REMAIN THE BIGGEST FORECAST CHALLENGE
FOLLOWED BY TEMPS WHICH MAY BE AFFECTED BY THE CONVECTION. AFTERNOON
WATER VAPOR IMAGERY SHOWS ONE UPPER LEVEL LOW SPINNING OVER THE
CENTRAL APPALACHIANS WHICH IS LOSING DEFINITION AS IS MOVES SLOWLY
NORTHWARD. THE NEXT UPPER LOW IS SPINNING OVER THE SOUTHERN
CANADIAN PRAIRIES WITH A TROUGH AXIS EXTENDING INTO THE DAKOTAS AND
LIFTING NORTHEAST. THE UPPER FLOW IS LESS AMPLIFIED FURTHER SOUTH OF
THE LOW ACROSS THE CENTRAL PLAINS BUT THERE ARE SEVERAL EMBEDDED
WAVES THAT ARE TRANSLATING NORTHEAST AS WELL. THE NEXT UPPER LOW OF
NOTE IS COMING ONSHORE OVER THE WEST COAST AND HELPING TO AMPLIFY A
RIDGE OVER OREGON/WASHINGTON. ENERGY EMANATING FROM THIS TROUGH WILL
BECOME A PLAYER IN OUR WEATHER LATER THIS WEEK. AT THE SURFACE...LOW
PRESSURE IS POSITIONED OVER NORTHWEST MINNESOTA WITH WEAKER LOW
PRESSURE SPREAD ACROSS THE PLAINS. A COOL FRONTAL BOUNDARY IS
STRETCHED FROM THE MN LOW BUT HAS BECOME DIFFICULT TO IDENTIFY
THANKS TO COLD POOLS FROM MORNING CONVECTION.
THROUGH THIS EVENING...TOUGH FORECAST ONCE AGAIN IN TERMS OF
CONVECTIVE POTENTIAL AND EVOLUTION THROUGH THE PERIOD. OUTFLOW
BOUNDARY FROM EARLIER IOWA CONVECTION IS NOW PUSHING INTO THE
WESTERN CWA TRIGGERING THUNDERSTORMS ALONG IT. A BETTER ORGANIZED
COMPLEX OF STORMS HAS DEVELOPED FROM THE EARLIER CONVECTION BUT IS
MOVING SOUTHEAST ACROSS NORTHERN MISSOURI INTO THE AXIS OF MUCH
BETTER INSTABILITY AS WELL AS BETTER MID LEVEL MOISTURE
ADVECTION. ADDITIONAL SCATTERED STORMS HAVE DEVELOPED OVER THE
SOUTHERN CWA LIKELY IN BETTER CONJUNCTION WITH THE WEAKENING UPPER
LOW OVER APPALACHIA. IN THE NEAR TERM...EXPECT THE OUTFLOW TO
CONTINUE EASTWARD ACROSS THE CWA TRIGGERING SCATTERED STORMS THROUGH
LATE AFTERNOON/EARLY EVENING. MESOANALYSIS SHOWS 2000+ J/KG OF MIXED
LAYER CAPE OVER THE AREA SUPPORTING STRONG UPDRAFTS BUT DEEP LAYER
SHEAR IS WEAK SO CORES SHOULD BE PRETTY PULSEY. LARGE HAIL AND
LOCALLY HEAVY DOWNPOURS ARE THE MAIN CONCERN. GUSTY WINDS ARE ALSO
POSSIBLE BUT RECENT AIRCRAFT SOUNDINGS FROM MDW DO NOT SHOW A TON OF
DRY LOW LEVEL AIR AND RAP ANALYSIS OF DCAPE IS LOW AS WELL. WOULD
EXPECT THAT THIS ACTIVITY WOULD WANE WITH SUNSET.
REST OF TONIGHT AND MONDAY...ATTENTION TURNS TO ADDITIONAL
CONVECTIVE POTENTIAL OVERNIGHT. WATER VAPOR SHOWS A WAVE OVER NE
KS/NW MO WHICH APPEARS TO BE TURNING MORE EASTWARD IN THE LAST FEW
SCANS. THIS IS LIKELY HELPING THE COMPLEX TAKING SHAPE OVER MO.
SHORT TERM/HIGH RES GUIDANCE HAS BEEN ALL OVER THE PLACE WITH HOW
CONVECTION EVOLVES THROUGH TONIGHT. THE MOIST SOUTHWESTERLY FLOW
WILL CONTINUE ACROSS THE REGION TONIGHT AND THE EARLIER COLD FRONTAL
BOUNDARY SEEMS TO BE DEVELOPING ONCE AGAIN ACROSS IOWA AS THE FLOW
HAS SETTLED FROM EARLIER CONVECTION. THIS IS SUPPORTIVE OF NEW
DEVELOPMENT TO THE WEST TONIGHT. THE OUTFLOW CURRENTLY WORKING INTO
THE LOCAL AREA EXTENDS INTO WEST-CENTRAL ILLINOIS AND THERE ARE
HINTS THAT THE SOUTHERN EXTENT OF IT AND LIKELY A BOUNDARY SET UP BY
THE CURRENT COMPLEX MAY STALL OUT SOMEWHERE NOT FAR FROM THE
SOUTHWESTERN CWA. IN ADDITION...THE KS/MO WAVE IS EXPECTED TO CROSS
THIS SAME AREA TONIGHT WHICH IS ALSO EXPECTED TO BE IN AN AREA OF
MID LEVEL WARM ADVECTION. THEREFORE IT IS POSSIBLE ROUNDS OF
CONVECTION COULD DEVELOP TO THE SOUTHWEST OF THE AREA AND ROLL
EASTWARD INTO THE SOUTHERN CWA OVERNIGHT. HAVE NOT MADE MUCH CHANGE
TO OVERNIGHT POPS BUT DID INCREASE THEM SOMEWHAT OVER THE FAR SOUTH.
AS FOR MONDAY...GUIDANCE REMAINS IN POOR AGREEMENT WITH TRACK OF
POTENTIAL UPPER WAVES BUT WATER VAPOR DOES SHOW SOME SIGNS OF A WAVE
COMING ACROSS THE FOUR CORNERS THIS AFTERNOON. THIS WOULD COME ACROSS
THE REGION LATER MONDAY BUT IT IS NOT CLEAR IF IT WILL BE MORE
FOCUSED TO THE NORTH OF THE AREA. WILL CONTINUE WITH MID CHANCE POPS
WITH LATER IN THE DAY MORE FAVORED. PROVIDED THE LATER TIMING WORKS
OUT THEN WE WILL HAVE A BETTER CHANCE TO WARM BUT THERE MAY BE
CONVECTIVE DEBRIS AROUND SO WILL HOLD TEMPS INTO THE MID 80S FOR
MOST AREAS.
TUESDAY THROUGH SUNDAY...THE UPPER FLOW BECOMES LESS AMPLIFIED
TUESDAY BUT WILL LIKELY STILL BE LITTERED WITH WAVES TRAVERSING IT.
HOT AND HUMID AIR WILL STILL BE IN PLACE WITH PRECIPITABLE WATER
VALUES HOVERING AROUND 1.75 INCHES. THESE FACTORS PROVIDE CONTINUED
SUPPORT FOR THUNDERSTORM DEVELOPMENT BUT THERE IS NOT MUCH TO KEY IN
ON FOR A COHERENT FORCING MECHANISM GIVEN THE LOW AMPLITUDE PATTERN.
BY WEDNESDAY...THERE IS SOME AGREEMENT ON SURFACE LOW PRESSURE
HAVING DEVELOPED ACROSS THE CANADIAN PRAIRIES WITH A TROUGH
AXIS/FRONT EXTENDING INTO MINNESOTA AND IOWA...WITH A SECONDARY LOW
POSSIBLY DEVELOPING ACROSS MINNESOTA. THE FRONT LOOKS TO CROSS THE
AREA LATER WEDNESDAY BRINGING SHOWER AND STORM CHANCES WITH IT.
UPPER RIDGING WILL BE BUILDING ACROSS THE WESTERN U.S. AND HIGH
PLAINS WITH A WAVE ORIGINATING FROM THE TROUGH OFF THE WEST COAST
OVERTOPPING THE RIDGE ACROSS THE CANADIAN ROCKIES AND DROPPING
SOUTHEASTWARD INTO THE GREAT LAKES WHILE AMPLIFYING LATE IN THE
WEEK. GFS AND ECMWF DIFFER ON HOW QUICKLY THIS OCCURS BUT THE SIGNAL
HAS BEEN CONSISTENT OVERALL. THIS WILL BRING A SHIFT TO
NORTHWESTERLY AT THE SURFACE AND ALOFT LATE IN THE WEEK AND
NOTICEABLY COOLER TEMPERATURES BY SATURDAY OR SO. LOW POPS WILL
CONTINUE WITH THE FLOW CONTINUING TO FAVOR WEAK SHORTWAVE PASSAGES.
HIGH TEMPS WILL LIKELY HOVER AROUND 90 TUESDAY AND WEDNESDAY
ASSUMING CONVECTION OR CONVECTIVE DEBRIS IS NOT AN ISSUE...WHICH
WOULD SIGNIFICANTLY LOWER HIGHS IF IT IS. WITH THE PASSAGE OF THE
SYSTEM LATER WEDNESDAY COOLER MID LEVEL AIR WILL FILTER IN KEEPING
HIGHS BACK IN THE 80S WITH UPPER 70S POSSIBLE FRIDAY AND SATURDAY.
MDB
&&
.HYDROLOGY...745 PM CDT
THE CONVECTIVE ACTIVITY THIS EVENING PRODUCED ISOLATED AREAS OF 2+
INCHES OF RAIN AND A BAND OF 1+ INCHES OF RAIN ACROSS LA SALLE
COUNTY. STILL CONSIDERED A FLASH FLOOD WATCH FOR THE WEST AND FAR
SOUTHWEST CWA GIVEN THE RAINFALL OF THE PAST FEW DAYS. CONFIDENCE
REMAINS LOW IN WHERE ORGANIZED CONVECTION WILL SET UP TONIGHT AND
MONDAY SO WILL HOLD OFF UNTIL AREAS AND TIMING CAN BE BETTER
DEFINED.
JEE/MDB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* SHOWERS WILL LINGER ACROSS THE TERMINALS OVER THE NEXT COUPLE OF
HOURS BEFORE DRIER CONDITIONS ARE EXPECTED FOR THE REMAINDER OF
THE EVENING.
* POSSIBILITY FOR A CONTINUED ACTIVE PERIOD WITH SEVERAL CHANCES
FOR SHOWERS/THUNDERSTORMS TO MOVE ACROSS THE TERMINALS EARLY
MONDAY MORNING THROUGH MONDAY EVENING.
* SOUTHERLY WINDS AROUND 10KT EXPECTED THIS EVENING.
RODRIGUEZ
//DISCUSSION...UPDATED 00Z...
THUNDERSTORMS HAVE HAVE SHOWN A RAPID DIMINISHING TREND OVER THE
LAST HOUR AND EXPECT THIS TO CONTINUE WITH ONLY SHOWERS EXPECTED.
AFTER THESE SHOWERS DIMINISH...DO EXPECT A DRY PERIOD FOR THE
REMAINDER OF THE EVENING BEFORE CHANCES FOR SHOWERS/THUNDERSTORMS
BEGIN TO INCREASE ONCE AGAIN EARLY MONDAY MORNING. SEVERAL CHANCES
FOR SHOWERS AND THUNDERSTORMS DO APPEAR POSSIBLE THROUGHOUT THE
DAY ON MONDAY...BUT WITH CONFIDENCE LOWER ON EXACT TIMING.
ALTHOUGH...MONDAY AFTERNOON APPEARS AS IF IT COULD BE AN ACTIVE
PERIOD. OUTSIDE OF THE THE PRECIP CHANCES THIS FORECAST PERIOD AND
MAYBE SOME PATCHY FOG EARLY MONDAY MORNING...EXPECT VFR CONDITIONS
WITH SOUTH/SOUTHWEST WINDS IN PLACE.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* HIGH CONFIDENCE WITH SHOWER TRENDS OVER THE NEXT COUPLE OF
HOURS.
* LOW MEDIUM CONFIDENCE WITH PRECIP TRENDS EARLY MONDAY MORNING
THROUGH MONDAY EVENING.
* MEDIUM CONFIDENCE WITH WIND SPEED AND DIRECTION THIS EVENING.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...
TUESDAY THROUGH FRIDAY...PERIODIC CHANCES OF TSRA.
SATURDAY...CHANCE OF SHRA.
RODRIGUEZ
&&
.MARINE...
420 PM CDT
A LARGE AREA OF HIGH PRESSURE EXTENDS FROM THE WESTERN ATLANTIC
SOUTHWESTWARD ACROSS THE SOUTHEASTERN U.S. AND THE NORTHERN GULF
OF MEXICO. THIS HIGH WILL BE MOVING ONLY VERY SLOWLY SOUTHEASTWARD
TONIGHT THROUGH THURSDAY. LOW PRESSURE NEAR LAKE WINNIPEG WILL BE
MOVING SLOWLY EASTWARD ACROSS ONTARIO...REACHING NEAR SOUTHERN JAMES
BAY BY TUESDAY MORNING. THEN...AN AREA OF LOW PRESSURE STRETCHING
FROM THE SOUTHERN CANADIAN PRAIRIE SOUTH ACROSS THE PLAINS WILL MOVE
NORTHEAST DURING TUESDAY AND WEDNESDAY. WITH HIGH PRESSURE SITUATED
FAR TO THE SOUTH THROUGH SOUTHEAST OF THE LAKE AND LOW PRESSURE FROM
FAR WEST THROUGH NORTHWEST TONIGHT INTO THURSDAY...MODERATE TO FRESH
WINDS WILL PERSIST OUT OF THE SOUTH TO SOUTHWEST.
THIS PERSISTENT FLOW WILL KEEP VERY MOIST AIR ACROSS THE WESTERN
GREAT LAKES REGION. WHILE MOST OF THE FOG HAD DISSIPATED ON NORTHERN
LAKE MICHIGAN...WITH THE MOIST AIR AND COOL LAKE WATER FOG IS
EXPECTED TO REDEVELOP TONIGHT AND BECOME DENSE IN AREAS. THE CURRENT
DENSE FOG ADVISORY FOR NORTHERN LAKE MICHIGAN WILL LIKELY NEED TO BE
EXTENDED INTO TUESDAY AND POSSIBLY WEDNESDAY AS THERE WILL BE NO
CHANGE IN AIRMASS UNTIL A COLD FRONT PUSHES ACROSS THE LAKE DURING
LATER WEDNESDAY AND WEDNESDAY NIGHT...SHIFTING WINDS TO OUT OF THE
WEST. A SECONDARY COLD FRONT WILL MOVE ACROSS THE LAKE AND SHIFT
WINDS TO OUT OF THE NORTHWEST DURING LATER THURSDAY AND THURSDAY
NIGHT.
TRS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565
UNTIL 7 AM MONDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS LINCOLN IL
703 PM CDT SUN JUN 23 2013
.DISCUSSION...
ISSUED 300 PM CDT SUN JUN 23 2013
TWO ONGOING COMPLEXES OF STORMS WILL HIGHLIGHT THE SHORT
TERM...A LINE OF STORMS IN THE NW AND A CLUSTER OF HEAVY RAIN IN
THE SE. HEAT AND PERIODIC STORM CHANCES WILL CONTINUE FOR MUCH OF
THE WEEK UNTIL A MORE SIGNIFICANT UPPER WAVE MAKES PROGRESS FROM
CANADA ACROSS THE GREAT LAKES AND CHANGES OUR UPPER FLOW OUT OF
THE NORTHWEST...AS A TROUGH DEVELOPS IN THE EAST AND A RIDGE TO
OUR WEST.
SHORT TERM...TONIGHT THROUGH THURSDAY.
THE HEAVY RAIN COMPLEX IN THE SOUTHEAST ASSOCIATED WITH A MESO-
VORTEX APPEARS TO BE WEAKENING...ALBEIT WITH STEADY RAINS
CONTINUING ACROSS A WATER-LOGGED AREA. SEVERAL FLASH FLOOD
WARNINGS REMAIN IN EFFECT INTO THIS EVENING FOR THAT AREA...WHERE
3-5 INCHES OF RAIN HAS FALLEN. SPC MESO-ANALYSIS GRAPHICS SHOW
INSTABILITY PARAMETERS IN THE SE AREA APPEAR TO BE
STABILIZING...WHILE BETTER SUPPORT FOR STRONG STORMS EXISTS AHEAD
OF THE LINE OF STORMS ENTERING OUR NW COUNTIES. ML-CAPE VALUES OF
3000-3500 J/KG SHOULD BE ENOUGH TO KEEP THEM ADVANCING INTO OUR
AREA. PRECIPITABLE WATER VALUES AROUND 1.7" AND VERY WEAK WINDS IN
THE MID-UPPER LEVELS LEND SUPPORT FOR HEAVY RAIN FROM THOSE STORMS
INTO THIS EVENING. THEY SHOULD MAINTAIN BETTER FORWARD PROGRESS
BASED ON THE MOVEMENT OF THE UPPER SHORTWAVE ON WATER VAPOR
SATELLITE. THE TRACK OF THE LINE OF STORMS SHOULD EVENTUALLY BEGIN
TO CURL TO THE SOUTHEAST. WE TRIED TO MATCH POPS TO CURRENT
CONDITIONS AND PROGRESS THEM THROUGH THE EVENING AND OVERNIGHT
UTILIZING SATELLITE AND RADAR TRENDS. MODELS HAVE GENERALLY BEEN
ALL OVER THE PLACE WITH CONVECTIVE SOLUTIONS...SO THEY HAVE NOT
BEEN MUCH HELP TO FORECAST DETAILS IN THE NEAR TERM.
WE USED GENERAL MODEL TRENDS WITH THE PROGRESS OF THE OVERALL
PATTERN THROUGH MID WEEK. WE EXPECT TO REMAIN IN THE WARM SECTOR
THROUGH THURSDAY...A GRADUAL BUILDING OF THE UPPER LEVEL RIDGE
INTO CENTRAL IL FOR TUESDAY AND TUESDAY NIGHT...WHICH MAY HELP
SUPPRESS STORMS FOR AROUND 24 HOURS. WE KEPT SLIGHT CHANCE POPS
TUE-TUE NIGHT AS A RESULT. UPPER TROUGHING REDEVELOPS FOR
WEDNESDAY AS A SURFACE TROUGH PROGRESSES ACROSS IL WED NIGHT
INTO THURSDAY. THAT WILL INITIALLY ESTABLISH NORTHWEST FLOW
ALOFT...AND BEGIN OUR AIRMASS CHANGE THAT IS PROJECTED TO FINALLY
BECOME ESTABLISHED NEXT WEEKEND.
IN THE MEAN TIME...TUESDAY AND WEDNESDAY LOOK TO BE OUR HOTTEST
DAYS OF THIS WEEK...AS HEAT INDEX READINGS CLIMB INTO THE 100-105
RANGE EACH AFTERNOON AND EARLY EVENING...OUTSIDE OF ANY STORM
COMPLEXES.
WE INCREASED POPS INTO THE CHANCE CATEGORY FOR WED AFTERNOON AND
CONTINUED CHANCE POPS WED NIGHT...CONFINING THEM TO THE EASTERN
AREAS ON THURSDAY AS THE TROUGH PUSHES EAST INTO INDIANA. WE MAY
SEE ANOTHER ROUND OF STRONG STORMS WITH HEAVY RAIN ALONG THAT
FRONT...AS PLENTY OF MOISTURE POOLING IS PROJECTED TO OCCUR AHEAD
OF THE SYSTEM.
LONG TERM...FRIDAY THROUGH SUNDAY.
A COOLING TREND SHOULD ALREADY BE NOTICEABLE ON FRIDAY AS SURFACE
WINDS TURN OUT OF THE NORTHWEST AND DEWPOINTS BEGIN TO DROP FROM
THE 70S INTO THE 60S. WE HELD ONTO A SLIGHT CHANCE OF SHOWERS AND
STORMS ON FRIDAY...AS THE UPPER TROUGH AXIS DEPARTS EASTWARD AND A
500MB SHORTWAVE ROTATES THROUGH THE BACK SIDE OF THE TROUGH. THE
DAY SHOULD BE DOMINATED BY CLOUDS HELPING TO KEEP HIGHS IN THE MID
80S. DRY CONDITIONS SHOULD RETURN FRI NIGHT...WITH A FEW
INSTABILITY SHOWERS POSSIBLE IN THE EAST ON SATURDAY AS THE COLD
POOL ALOFT PASSES OVER THE AREA. HIGHS ON SATURDAY AND SUNDAY
SHOULD TOP OUT IN THE LOWER 80S WITH OVERNIGHT LOWS IN THE LOW
60S...WITH MUCH LESS HUMIDITY IN THE AIR.
&&
.AVIATION...
ISSUED 658 PM CDT SUN JUN 23 2013
ADJUSTING FORECAST IN THE SHORT TERM TO HANDLE THE SLOWLY
DWINDLING CONVECTION. PRECIP FALLING APART A BIT QUICKER THAN PREV
MODEL RUNS ANTICIPATED...AND AS A RESULT HAVE LEFT TOO MUCH
MENTION OF PRECIP IN MOST OF THE TAFS. CONCERN FOR PRECIP
CONTINUES THROUGH TOMORROW THOUGH MODELS ARE ALL OVER THE PLACE.
MOST FAITH IN HRRR FOR NOW...WHICH HAS A MORE SCT SIGNATURE. WILL
AWAIT NEXT RUN BEFORE CALLING PRECIP AND TIMING FOR TOMORROW.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
657 PM CDT SUN JUN 23 2013
.DISCUSSION...
304 PM CDT
SHOWER/THUNDER CHANCES REMAIN THE BIGGEST FORECAST CHALLENGE
FOLLOWED BY TEMPS WHICH MAY BE AFFECTED BY THE CONVECTION. AFTERNOON
WATER VAPOR IMAGERY SHOWS ONE UPPER LEVEL LOW SPINNING OVER THE
CENTRAL APPALACHIANS WHICH IS LOSING DEFINITION AS IS MOVES SLOWLY
NORTHWARD. THE NEXT UPPER LOW IS SPINNING OVER THE SOUTHERN
CANADIAN PRAIRIES WITH A TROUGH AXIS EXTENDING INTO THE DAKOTAS AND
LIFTING NORTHEAST. THE UPPER FLOW IS LESS AMPLIFIED FURTHER SOUTH OF
THE LOW ACROSS THE CENTRAL PLAINS BUT THERE ARE SEVERAL EMBEDDED
WAVES THAT ARE TRANSLATING NORTHEAST AS WELL. THE NEXT UPPER LOW OF
NOTE IS COMING ONSHORE OVER THE WEST COAST AND HELPING TO AMPLIFY A
RIDGE OVER OREGON/WASHINGTON. ENERGY EMANATING FROM THIS TROUGH WILL
BECOME A PLAYER IN OUR WEATHER LATER THIS WEEK. AT THE SURFACE...LOW
PRESSURE IS POSITIONED OVER NORTHWEST MINNESOTA WITH WEAKER LOW
PRESSURE SPREAD ACROSS THE PLAINS. A COOL FRONTAL BOUNDARY IS
STRETCHED FROM THE MN LOW BUT HAS BECOME DIFFICULT TO IDENTIFY
THANKS TO COLD POOLS FROM MORNING CONVECTION.
THROUGH THIS EVENING...TOUGH FORECAST ONCE AGAIN IN TERMS OF
CONVECTIVE POTENTIAL AND EVOLUTION THROUGH THE PERIOD. OUTFLOW
BOUNDARY FROM EARLIER IOWA CONVECTION IS NOW PUSHING INTO THE
WESTERN CWA TRIGGERING THUNDERSTORMS ALONG IT. A BETTER ORGANIZED
COMPLEX OF STORMS HAS DEVELOPED FROM THE EARLIER CONVECTION BUT IS
MOVING SOUTHEAST ACROSS NORTHERN MISSOURI INTO THE AXIS OF MUCH
BETTER INSTABILITY AS WELL AS BETTER MID LEVEL MOISTURE
ADVECTION. ADDITIONAL SCATTERED STORMS HAVE DEVELOPED OVER THE
SOUTHERN CWA LIKELY IN BETTER CONJUNCTION WITH THE WEAKENING UPPER
LOW OVER APPALACHIA. IN THE NEAR TERM...EXPECT THE OUTFLOW TO
CONTINUE EASTWARD ACROSS THE CWA TRIGGERING SCATTERED STORMS THROUGH
LATE AFTERNOON/EARLY EVENING. MESOANALYSIS SHOWS 2000+ J/KG OF MIXED
LAYER CAPE OVER THE AREA SUPPORTING STRONG UPDRAFTS BUT DEEP LAYER
SHEAR IS WEAK SO CORES SHOULD BE PRETTY PULSEY. LARGE HAIL AND
LOCALLY HEAVY DOWNPOURS ARE THE MAIN CONCERN. GUSTY WINDS ARE ALSO
POSSIBLE BUT RECENT AIRCRAFT SOUNDINGS FROM MDW DO NOT SHOW A TON OF
DRY LOW LEVEL AIR AND RAP ANALYSIS OF DCAPE IS LOW AS WELL. WOULD
EXPECT THAT THIS ACTIVITY WOULD WANE WITH SUNSET.
REST OF TONIGHT AND MONDAY...ATTENTION TURNS TO ADDITIONAL
CONVECTIVE POTENTIAL OVERNIGHT. WATER VAPOR SHOWS A WAVE OVER NE
KS/NW MO WHICH APPEARS TO BE TURNING MORE EASTWARD IN THE LAST FEW
SCANS. THIS IS LIKELY HELPING THE COMPLEX TAKING SHAPE OVER MO.
SHORT TERM/HIGH RES GUIDANCE HAS BEEN ALL OVER THE PLACE WITH HOW
CONVECTION EVOLVES THROUGH TONIGHT. THE MOIST SOUTHWESTERLY FLOW
WILL CONTINUE ACROSS THE REGION TONIGHT AND THE EARLIER COLD FRONTAL
BOUNDARY SEEMS TO BE DEVELOPING ONCE AGAIN ACROSS IOWA AS THE FLOW
HAS SETTLED FROM EARLIER CONVECTION. THIS IS SUPPORTIVE OF NEW
DEVELOPMENT TO THE WEST TONIGHT. THE OUTFLOW CURRENTLY WORKING INTO
THE LOCAL AREA EXTENDS INTO WEST-CENTRAL ILLINOIS AND THERE ARE
HINTS THAT THE SOUTHERN EXTENT OF IT AND LIKELY A BOUNDARY SET UP BY
THE CURRENT COMPLEX MAY STALL OUT SOMEWHERE NOT FAR FROM THE
SOUTHWESTERN CWA. IN ADDITION...THE KS/MO WAVE IS EXPECTED TO CROSS
THIS SAME AREA TONIGHT WHICH IS ALSO EXPECTED TO BE IN AN AREA OF
MID LEVEL WARM ADVECTION. THEREFORE IT IS POSSIBLE ROUNDS OF
CONVECTION COULD DEVELOP TO THE SOUTHWEST OF THE AREA AND ROLL
EASTWARD INTO THE SOUTHERN CWA OVERNIGHT. HAVE NOT MADE MUCH CHANGE
TO OVERNIGHT POPS BUT DID INCREASE THEM SOMEWHAT OVER THE FAR SOUTH.
AS FOR MONDAY...GUIDANCE REMAINS IN POOR AGREEMENT WITH TRACK OF
POTENTIAL UPPER WAVES BUT WATER VAPOR DOES SHOW SOME SIGNS OF A WAVE
COMING ACROSS THE FOUR CORNERS THIS AFTERNOON. THIS WOULD COME ACROSS
THE REGION LATER MONDAY BUT IT IS NOT CLEAR IF IT WILL BE MORE
FOCUSED TO THE NORTH OF THE AREA. WILL CONTINUE WITH MID CHANCE POPS
WITH LATER IN THE DAY MORE FAVORED. PROVIDED THE LATER TIMING WORKS
OUT THEN WE WILL HAVE A BETTER CHANCE TO WARM BUT THERE MAY BE
CONVECTIVE DEBRIS AROUND SO WILL HOLD TEMPS INTO THE MID 80S FOR
MOST AREAS.
TUESDAY THROUGH SUNDAY...THE UPPER FLOW BECOMES LESS AMPLIFIED
TUESDAY BUT WILL LIKELY STILL BE LITTERED WITH WAVES TRAVERSING IT.
HOT AND HUMID AIR WILL STILL BE IN PLACE WITH PRECIPITABLE WATER
VALUES HOVERING AROUND 1.75 INCHES. THESE FACTORS PROVIDE CONTINUED
SUPPORT FOR THUNDERSTORM DEVELOPMENT BUT THERE IS NOT MUCH TO KEY IN
ON FOR A COHERENT FORCING MECHANISM GIVEN THE LOW AMPLITUDE PATTERN.
BY WEDNESDAY...THERE IS SOME AGREEMENT ON SURFACE LOW PRESSURE
HAVING DEVELOPED ACROSS THE CANADIAN PRAIRIES WITH A TROUGH
AXIS/FRONT EXTENDING INTO MINNESOTA AND IOWA...WITH A SECONDARY LOW
POSSIBLY DEVELOPING ACROSS MINNESOTA. THE FRONT LOOKS TO CROSS THE
AREA LATER WEDNESDAY BRINGING SHOWER AND STORM CHANCES WITH IT.
UPPER RIDGING WILL BE BUILDING ACROSS THE WESTERN U.S. AND HIGH
PLAINS WITH A WAVE ORIGINATING FROM THE TROUGH OFF THE WEST COAST
OVERTOPPING THE RIDGE ACROSS THE CANADIAN ROCKIES AND DROPPING
SOUTHEASTWARD INTO THE GREAT LAKES WHILE AMPLIFYING LATE IN THE
WEEK. GFS AND ECMWF DIFFER ON HOW QUICKLY THIS OCCURS BUT THE SIGNAL
HAS BEEN CONSISTENT OVERALL. THIS WILL BRING A SHIFT TO
NORTHWESTERLY AT THE SURFACE AND ALOFT LATE IN THE WEEK AND
NOTICEABLY COOLER TEMPERATURES BY SATURDAY OR SO. LOW POPS WILL
CONTINUE WITH THE FLOW CONTINUING TO FAVOR WEAK SHORTWAVE PASSAGES.
HIGH TEMPS WILL LIKELY HOVER AROUND 90 TUESDAY AND WEDNESDAY
ASSUMING CONVECTION OR CONVECTIVE DEBRIS IS NOT AN ISSUE...WHICH
WOULD SIGNIFICANTLY LOWER HIGHS IF IT IS. WITH THE PASSAGE OF THE
SYSTEM LATER WEDNESDAY COOLER MID LEVEL AIR WILL FILTER IN KEEPING
HIGHS BACK IN THE 80S WITH UPPER 70S POSSIBLE FRIDAY AND SATURDAY.
MDB
&&
.HYDROLOGY...
304 PM CDT
GAVE CONSIDERATION TO A FLASH FLOOD WATCH FOR THE WEST AND FAR
SOUTHWEST CWA GIVEN THE RAINFALL OF THE PAST FEW DAYS. GIVEN
FAIRLY LOW CONFIDENCE IN WHERE ORGANIZED CONVECTION WILL SET UP
TONIGHT AND MONDAY WILL HOLD OFF UNTIL AREAS AND TIMING CAN BE
BETTER DEFINED. CURRENT ACTIVITY IS STILL MOVING FAIRLY STEADILY
BUT 1-1.5 INCHES OF RAIN PER HOUR ARE POSSIBLE LOCALLY. WILL PASS
THE CONCERN ABOUT A WATCH TO THE EVENING SHIFT.
MDB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* SHOWERS WILL LINGER ACROSS THE TERMINALS OVER THE NEXT COUPLE OF
HOURS BEFORE DRIER CONDITIONS ARE EXPECTED FOR THE REMAINDER OF
THE EVENING.
* POSSIBILITY FOR A CONTINUED ACTIVE PERIOD WITH SEVERAL CHANCES
FOR SHOWERS/THUNDERSTORMS TO MOVE ACROSS THE TERMINALS EARLY
MONDAY MORNING THROUGH MONDAY EVENING.
* SOUTHERLY WINDS AROUND 10KT EXPECTED THIS EVENING.
RODRIGUEZ
//DISCUSSION...UPDATED 00Z...
THUNDERSTORMS HAVE HAVE SHOWN A RAPID DIMINISHING TREND OVER THE
LAST HOUR AND EXPECT THIS TO CONTINUE WITH ONLY SHOWERS EXPECTED.
AFTER THESE SHOWERS DIMINISH...DO EXPECT A DRY PERIOD FOR THE
REMAINDER OF THE EVENING BEFORE CHANCES FOR SHOWERS/THUNDERSTORMS
BEGIN TO INCREASE ONCE AGAIN EARLY MONDAY MORNING. SEVERAL CHANCES
FOR SHOWERS AND THUNDERSTORMS DO APPEAR POSSIBLE THROUGHOUT THE
DAY ON MONDAY...BUT WITH CONFIDENCE LOWER ON EXACT TIMING.
ALTHOUGH...MONDAY AFTERNOON APPEARS AS IF IT COULD BE AN ACTIVE
PERIOD. OUTSIDE OF THE THE PRECIP CHANCES THIS FORECAST PERIOD AND
MAYBE SOME PATCHY FOG EARLY MONDAY MORNING...EXPECT VFR CONDITIONS
WITH SOUTH/SOUTHWEST WINDS IN PLACE.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* HIGH CONFIDENCE WITH SHOWER TRENDS OVER THE NEXT COUPLE OF
HOURS.
* LOW MEDIUM CONFIDENCE WITH PRECIP TRENDS EARLY MONDAY MORNING
THROUGH MONDAY EVENING.
* MEDIUM CONFIDENCE WITH WIND SPEED AND DIRECTION THIS EVENING.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...
TUESDAY THROUGH FRIDAY...PERIODIC CHANCES OF TSRA.
SATURDAY...CHANCE OF SHRA.
RODRIGUEZ
&&
.MARINE...
420 PM CDT
A LARGE AREA OF HIGH PRESSURE EXTENDS FROM THE WESTERN ATLANTIC
SOUTHWESTWARD ACROSS THE SOUTHEASTERN U.S. AND THE NORTHERN GULF
OF MEXICO. THIS HIGH WILL BE MOVING ONLY VERY SLOWLY SOUTHEASTWARD
TONIGHT THROUGH THURSDAY. LOW PRESSURE NEAR LAKE WINNIPEG WILL BE
MOVING SLOWLY EASTWARD ACROSS ONTARIO...REACHING NEAR SOUTHERN JAMES
BAY BY TUESDAY MORNING. THEN...AN AREA OF LOW PRESSURE STRETCHING
FROM THE SOUTHERN CANADIAN PRAIRIE SOUTH ACROSS THE PLAINS WILL MOVE
NORTHEAST DURING TUESDAY AND WEDNESDAY. WITH HIGH PRESSURE SITUATED
FAR TO THE SOUTH THROUGH SOUTHEAST OF THE LAKE AND LOW PRESSURE FROM
FAR WEST THROUGH NORTHWEST TONIGHT INTO THURSDAY...MODERATE TO FRESH
WINDS WILL PERSIST OUT OF THE SOUTH TO SOUTHWEST.
THIS PERSISTENT FLOW WILL KEEP VERY MOIST AIR ACROSS THE WESTERN
GREAT LAKES REGION. WHILE MOST OF THE FOG HAD DISSIPATED ON NORTHERN
LAKE MICHIGAN...WITH THE MOIST AIR AND COOL LAKE WATER FOG IS
EXPECTED TO REDEVELOP TONIGHT AND BECOME DENSE IN AREAS. THE CURRENT
DENSE FOG ADVISORY FOR NORTHERN LAKE MICHIGAN WILL LIKELY NEED TO BE
EXTENDED INTO TUESDAY AND POSSIBLY WEDNESDAY AS THERE WILL BE NO
CHANGE IN AIRMASS UNTIL A COLD FRONT PUSHES ACROSS THE LAKE DURING
LATER WEDNESDAY AND WEDNESDAY NIGHT...SHIFTING WINDS TO OUT OF THE
WEST. A SECONDARY COLD FRONT WILL MOVE ACROSS THE LAKE AND SHIFT
WINDS TO OUT OF THE NORTHWEST DURING LATER THURSDAY AND THURSDAY
NIGHT.
TRS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565
UNTIL 7 AM MONDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS LINCOLN IL
1258 PM CDT SAT JUN 22 2013
.DISCUSSION...
ISSUED 1044 AM CDT SAT JUN 22 2013
CONVECTIVE CHANCES REMAIN MAIN CONCERN TODAY. PRIMARY OUTFLOW
BOUNDARY IS CURRENTLY PUSHING SOUTH INTO THE NORTHEAST CWA WITH
SCATTERED THUNDERSTORMS DEVELOPING BEHIND THIS FEATURE. THIS
SHOULD CONTINUE INTO EARLY AFTERNOON AS THE BOUNDARY SLIPS
SOUTH...HOWEVER IT SHOULD EVENTUALLY SLOW AND STALL /UNLESS MORE
VIGOROUS CONVECTION KEEPS COLD POOL GOING/ AS IT ENCOUNTERS 10-20
KT SOUTHWEST SYNOPTIC FLOW. SCATTERED SHOWERS AND SPRINKLES
AFFECTING PARTS OF THE WESTERN CWA OUT OF A MID LEVEL DECK AND
FEEL THIS AREA COULD FILL IN WITH SCATTERED TSTMS WITH DAYTIME
HEATING. 12Z ILX SOUNDING SHOWED HIGH CAPES AND VERY WEAK WINDS
ALOFT...WHICH COMBINED WITH A 2 INCH P/W MAKES HEAVY RAIN RATES
AND FREQUENT LIGHTNING MAIN THREATS WITH STORMS TODAY. ISOLATED
PULSE TYPE NEAR SVR POSSIBLE DUE TO PRECIP LOADING BUT LOW BULK
SHEAR MAKES MORE ORGANIZED SVR UNLIKELY. HAVE INCREASED POPS TO LOW
CHANCE OVER MOST OF THE CWA WITH LIKELY POPS IN THE NE CWA WHERE
MORE SIGNIFICANT OUTFLOW BOUNDARY SHIFTS THROUGH NEXT FEW HOURS.
SUNNIER LOCATIONS SHOULD GET INTO THE LOWER 90S AND WITH DEWPOINTS
IN THE LOWER 70S PEAK HEAT INDICES NEAR 100 POSSIBLE.
&&
.AVIATION...
ISSUED 1258 PM CDT SAT JUN 22 2013
OUTFLOW BOUNDARY PUSHING THROUGH THE EASTERN TERMINAL WILL PRODUCE
HIGHEST COVERAGE TSRA EARLY THIS AFTERNOON AFFECTING CMI AND
POSSIBLY DEC. VERY HEAVY RAIN RATES BRINGING VSBYS DOWN BELOW 1SM
IN HEAVIER STORMS. OTHERWISE ONLY ISOLATED ACTIVITY EXPECTED
FARTHER WEST AND HAVE CARRIED VCTS THROUGH AFTERNOON. AFTER THIS
SYSTEM PUSHES SOUTH NOT MUCH FOCUS FOR ADDITIONAL STORMS INTO
SUNDAY MORNING AND MAINLY VFR SKIES EXPECTED. LATER FORECASTS WILL
ADDRESS POSSIBLE MVFR FOG THAT COULD DEVELOP LATE TONIGHT IN
LIGHTER WIND REGIME. SOUTHWEST WINDS WILL PICK UP OVER 10 KTS
AFTER 14Z/SUN.
25
&&
.PREV DISCUSSION...
ISSUED 250 AM CDT SAT JUN 22 2013
2 AM SATELLITE IMAGERY AND RADAR DATA SHOWING A PAIR OF MCS
SYSTEMS MERGING FROM SOUTH DAKOTA EASTWARD INTO SOUTHERN
WISCONSIN. EASTERN END OF THE LINE OF STORMS HAS MADE A SOUTHWARD
PUSH INTO NORTHEAST ILLINOIS...WITH THIS PART OF THE MCS BECOMING
THE DOMINANT ONE AS LIGHTNING DIMINISHES OVER SOUTHERN MINNESOTA.
LINGERING BOUNDARY FROM THE STORMS IN OUR AREA YESTERDAY WRAPS
AROUND THE SOUTHWEST AND SOUTHEAST PARTS OF THE FORECAST AREA.
STILL SEEING A FEW SPRINKLES IN THE FAR SOUTHEAST CWA WITH THIS
BOUNDARY.
FORECAST CHALLENGES FOR THIS PACKAGE GENERALLY REVOLVE AROUND
TIMING OF THUNDERSTORM CHANCES...AS WELL AS THE ONGOING HEAT AND
HUMIDITY.
SHORT TERM...TODAY THROUGH MONDAY...
MODELS ARE STRUGGLING TO GET A HANDLE ON THE CURRENT SITUATION...
WITH THE HRRR AND THE REGIONAL CANADIAN MODEL CLOSEST TO REALITY.
NEITHER OF THESE MODELS SHOW THE STORMS MAKING IT AS FAR SOUTH AS
OUR FORECAST AREA...BUT AS THE MCS FROM YESTERDAY SHOWED...THAT
OUTCOME IS DEFINITELY NOT GUARANTEED. WILL INCLUDE SOME ISOLATED
THUNDERSTORM MENTION IN THE NORTHEAST THIRD OF THE CWA THIS
MORNING...BETWEEN THIS LINE AND POTENTIALLY SOME DEVELOPMENT ALONG
THE OUTFLOW BOUNDARY...WITH AROUND 30 PERCENT CHANCES ACROSS THE
NORTHEAST DURING THE AFTERNOON. HAVE MENTIONED ISOLATED STORMS
ELSEWHERE THIS AFTERNOON AND EARLY EVENING.
FOCUS CONTINUES TO BE WITH TIMING OF VARIOUS MCS FEATURES THIS
WEEKEND. DEVELOPMENT ACROSS IOWA/MINNESOTA ON SUNDAY EXPECTED TO
EXTEND SOUTHWEST INTO MISSOURI...BUT ONLY THE NAM BRINGS ANY OF IT
THIS FAR EAST BY MONDAY MORNING. HAVE LIMITED ANY 30 PERCENT OR
HIGHER POPS TO THE FAR NORTHWEST LATE SUNDAY NIGHT... WITH MORE
WIDESPREAD CHANCES MONDAY. THE ECMWF AND CANADIAN MODELS SHOW THE
MCS SPREADING OVER THE FORECAST AREA... WHILE THE NAM AND GFS
SHUNT IT MORE TO THE NORTHEAST. SEVERE WEATHER POTENTIAL APPEARS
TO INCREASE BY MONDAY...MAINLY IN THE NORTHWEST CWA.
HAVE KEPT HIGH TEMPERATURES RIGHT AROUND 90 DEGREES FOR THE NEXT
FEW DAYS...WITH HEAT INDEX VALUES IN THE MID TO UPPER 90S. WILL
HAVE TO KEEP AN EYE ON HIGHS FOR MONDAY THOUGH...AS THEY COULD BE
LOWER IF THIS MCS DOES PAN OUT.
LONG TERM...TUESDAY THROUGH FRIDAY...
BROAD EAST-WEST RIDGE EXPECTED TO COVER THE SOUTH HALF OF THE
CONUS MUCH OF THE WEEK...WITH THE MAIN STORM TRACK ACROSS THE
NORTHERN STATES. MCS TRACKS REMAINS THE CONCERN AND ALTHOUGH MANY
OF THEM ARE FURTHER NORTH...LEFTOVER OUTFLOWS MAKE IT DIFFICULT TO
PIN DOWN ANY DRY PERIODS WITH ANY CERTAINTY. HIGHEST POPS FROM
WEDNESDAY NIGHT TO FRIDAY ARE TIED INTO PASSAGE OF A COLD FRONT...
WHICH MAY TAKE UNTIL EARLY FRIDAY TO FULLY PASS THE REGION AS THE
UPPER RIDGING BUILDS ACROSS THE ROCKIES AND PUTS THE MIDWEST MORE
OF A TROUGH. THIS PARTICULAR PATTERN WOULD SHOW THE HEAT FINALLY
BREAKING ON FRIDAY...WITH COOLER CONDITIONS NEXT WEEKEND.
GEELHART
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1044 AM CDT SAT JUN 22 2013
.DISCUSSION...
ISSUED 1044 AM CDT SAT JUN 22 2013
CONVECTIVE CHANCES REMAIN MAIN CONCERN TODAY. PRIMARY OUTFLOW
BOUNDARY IS CURRENTLY PUSHING SOUTH INTO THE NORTHEAST CWA WITH
SCATTERED THUNDERSTORMS DEVELOPING BEHIND THIS FEATURE. THIS
SHOULD CONTINUE INTO EARLY AFTERNOON AS THE BOUNDARY SLIPS
SOUTH...HOWEVER IT SHOULD EVENTUALLY SLOW AND STALL /UNLESS MORE
VIGOROUS CONVECTION KEEPS COLD POOL GOING/ AS IT ENCOUNTERS 10-20
KT SOUTHWEST SYNOPTIC FLOW. SCATTERED SHOWERS AND SPRINKLES
AFFECTING PARTS OF THE WESTERN CWA OUT OF A MID LEVEL DECK AND
FEEL THIS AREA COULD FILL IN WITH SCATTERED TSTMS WITH DAYTIME
HEATING. 12Z ILX SOUNDING SHOWED HIGH CAPES AND VERY WEAK WINDS
ALOFT...WHICH COMBINED WITH A 2 INCH P/W MAKES HEAVY RAIN RATES
AND FREQUENT LIGHTNING MAIN THREATS WITH STORMS TODAY. ISOLATED
PULSE TYPE NEAR SVR POSSIBLE DUE TO PRECIP LOADING BUT LOW BULK
SHEAR MAKES MORE ORGANIZED SVR UNLIKELY. HAVE INCREASED POPS TO LOW
CHANCE OVER MOST OF THE CWA WITH LIKELY POPS IN THE NE CWA WHERE
MORE SIGNIFICANT OUTFLOW BOUNDARY SHIFTS THROUGH NEXT FEW HOURS.
SUNNIER LOCATIONS SHOULD GET INTO THE LOWER 90S AND WITH DEWPOINTS
IN THE LOWER 70S PEAK HEAT INDICES NEAR 100 POSSIBLE.
25
&&
.AVIATION...
ISSUED 520 AM CDT SAT JUN 22 2013
COVERAGE OF TSRA AND THE AFFECTS ON CIGS/VSBYS THIS FORECAST PERIOD.
MID LEVEL MOISTURE HAS RAPIDLY DEVELOPED ACRS THE AREA THIS MORNING
IN ADVANCE OF A WEAK UPPER LEVEL DISTURBANCE COUPLED WITH SOME
ELEVATED INSTABILITY. JUST HOW MUCH SHOWER DEVELOPMENT TAKES PLACE
IS STILL IN QUESTION AHEAD OF THIS SYSTEM...BUT WILL COVER FOR NOW
WITH VCTS AND CONTINUE TO TRY TO PIN DOWN SOME BETTER TIMING OF
STORMS IN THE AFTN HOURS. STILL APPEARS THE COVERAGE SHOULD QUICKLY
DIMINISH JUST AFTR SUNSET THIS EVENING WITH MAIN MID AND HIGH LEVEL
MOISTURE REMAINING TONIGHT. IF SKIES SHOULD CLEAR OUT LATER TONIGHT
WE MAY HAVE TO DEAL WITH SOME PATCHY GROUND FOG...BUT FOR NOW WILL
LEAVE OUT OF TAFS. SFC WINDS WILL REMAIN OUT OF A SSW (180-210)
DIRECTION THRU THIS FORECAST PERIOD. SPEEDS WILL RANGE FROM 10 TO
15 KTS TODAY WITH A FEW GUSTS IN THE 15 TO 20 KT RANGE AND THEN
DIMINISH TO AROUND 10 KTS THIS EVENING.
SMITH
&&
.PREV DISCUSSION...
ISSUED 250 AM CDT SAT JUN 22 2013
2 AM SATELLITE IMAGERY AND RADAR DATA SHOWING A PAIR OF MCS
SYSTEMS MERGING FROM SOUTH DAKOTA EASTWARD INTO SOUTHERN
WISCONSIN. EASTERN END OF THE LINE OF STORMS HAS MADE A SOUTHWARD
PUSH INTO NORTHEAST ILLINOIS...WITH THIS PART OF THE MCS BECOMING
THE DOMINANT ONE AS LIGHTNING DIMINISHES OVER SOUTHERN MINNESOTA.
LINGERING BOUNDARY FROM THE STORMS IN OUR AREA YESTERDAY WRAPS
AROUND THE SOUTHWEST AND SOUTHEAST PARTS OF THE FORECAST AREA.
STILL SEEING A FEW SPRINKLES IN THE FAR SOUTHEAST CWA WITH THIS
BOUNDARY.
FORECAST CHALLENGES FOR THIS PACKAGE GENERALLY REVOLVE AROUND
TIMING OF THUNDERSTORM CHANCES...AS WELL AS THE ONGOING HEAT AND
HUMIDITY.
SHORT TERM...TODAY THROUGH MONDAY...
MODELS ARE STRUGGLING TO GET A HANDLE ON THE CURRENT SITUATION...
WITH THE HRRR AND THE REGIONAL CANADIAN MODEL CLOSEST TO REALITY.
NEITHER OF THESE MODELS SHOW THE STORMS MAKING IT AS FAR SOUTH AS
OUR FORECAST AREA...BUT AS THE MCS FROM YESTERDAY SHOWED...THAT
OUTCOME IS DEFINITELY NOT GUARANTEED. WILL INCLUDE SOME ISOLATED
THUNDERSTORM MENTION IN THE NORTHEAST THIRD OF THE CWA THIS
MORNING...BETWEEN THIS LINE AND POTENTIALLY SOME DEVELOPMENT ALONG
THE OUTFLOW BOUNDARY...WITH AROUND 30 PERCENT CHANCES ACROSS THE
NORTHEAST DURING THE AFTERNOON. HAVE MENTIONED ISOLATED STORMS
ELSEWHERE THIS AFTERNOON AND EARLY EVENING.
FOCUS CONTINUES TO BE WITH TIMING OF VARIOUS MCS FEATURES THIS
WEEKEND. DEVELOPMENT ACROSS IOWA/MINNESOTA ON SUNDAY EXPECTED TO
EXTEND SOUTHWEST INTO MISSOURI...BUT ONLY THE NAM BRINGS ANY OF IT
THIS FAR EAST BY MONDAY MORNING. HAVE LIMITED ANY 30 PERCENT OR
HIGHER POPS TO THE FAR NORTHWEST LATE SUNDAY NIGHT... WITH MORE
WIDESPREAD CHANCES MONDAY. THE ECMWF AND CANADIAN MODELS SHOW THE
MCS SPREADING OVER THE FORECAST AREA... WHILE THE NAM AND GFS
SHUNT IT MORE TO THE NORTHEAST. SEVERE WEATHER POTENTIAL APPEARS
TO INCREASE BY MONDAY...MAINLY IN THE NORTHWEST CWA.
HAVE KEPT HIGH TEMPERATURES RIGHT AROUND 90 DEGREES FOR THE NEXT
FEW DAYS...WITH HEAT INDEX VALUES IN THE MID TO UPPER 90S. WILL
HAVE TO KEEP AN EYE ON HIGHS FOR MONDAY THOUGH...AS THEY COULD BE
LOWER IF THIS MCS DOES PAN OUT.
LONG TERM...TUESDAY THROUGH FRIDAY...
BROAD EAST-WEST RIDGE EXPECTED TO COVER THE SOUTH HALF OF THE
CONUS MUCH OF THE WEEK...WITH THE MAIN STORM TRACK ACROSS THE
NORTHERN STATES. MCS TRACKS REMAINS THE CONCERN AND ALTHOUGH MANY
OF THEM ARE FURTHER NORTH...LEFTOVER OUTFLOWS MAKE IT DIFFICULT TO
PIN DOWN ANY DRY PERIODS WITH ANY CERTAINTY. HIGHEST POPS FROM
WEDNESDAY NIGHT TO FRIDAY ARE TIED INTO PASSAGE OF A COLD FRONT...
WHICH MAY TAKE UNTIL EARLY FRIDAY TO FULLY PASS THE REGION AS THE
UPPER RIDGING BUILDS ACROSS THE ROCKIES AND PUTS THE MIDWEST MORE
OF A TROUGH. THIS PARTICULAR PATTERN WOULD SHOW THE HEAT FINALLY
BREAKING ON FRIDAY...WITH COOLER CONDITIONS NEXT WEEKEND.
GEELHART
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
523 AM CDT SAT JUN 22 2013
.DISCUSSION...
ISSUED 250 AM CDT SAT JUN 22 2013
2 AM SATELLITE IMAGERY AND RADAR DATA SHOWING A PAIR OF MCS
SYSTEMS MERGING FROM SOUTH DAKOTA EASTWARD INTO SOUTHERN
WISCONSIN. EASTERN END OF THE LINE OF STORMS HAS MADE A SOUTHWARD
PUSH INTO NORTHEAST ILLINOIS...WITH THIS PART OF THE MCS BECOMING
THE DOMINANT ONE AS LIGHTNING DIMINISHES OVER SOUTHERN MINNESOTA.
LINGERING BOUNDARY FROM THE STORMS IN OUR AREA YESTERDAY WRAPS
AROUND THE SOUTHWEST AND SOUTHEAST PARTS OF THE FORECAST AREA.
STILL SEEING A FEW SPRINKLES IN THE FAR SOUTHEAST CWA WITH THIS
BOUNDARY.
FORECAST CHALLENGES FOR THIS PACKAGE GENERALLY REVOLVE AROUND
TIMING OF THUNDERSTORM CHANCES...AS WELL AS THE ONGOING HEAT AND
HUMIDITY.
SHORT TERM...TODAY THROUGH MONDAY...
MODELS ARE STRUGGLING TO GET A HANDLE ON THE CURRENT SITUATION...
WITH THE HRRR AND THE REGIONAL CANADIAN MODEL CLOSEST TO REALITY.
NEITHER OF THESE MODELS SHOW THE STORMS MAKING IT AS FAR SOUTH AS
OUR FORECAST AREA...BUT AS THE MCS FROM YESTERDAY SHOWED...THAT
OUTCOME IS DEFINITELY NOT GUARANTEED. WILL INCLUDE SOME ISOLATED
THUNDERSTORM MENTION IN THE NORTHEAST THIRD OF THE CWA THIS
MORNING...BETWEEN THIS LINE AND POTENTIALLY SOME DEVELOPMENT ALONG
THE OUTFLOW BOUNDARY...WITH AROUND 30 PERCENT CHANCES ACROSS THE
NORTHEAST DURING THE AFTERNOON. HAVE MENTIONED ISOLATED STORMS
ELSEWHERE THIS AFTERNOON AND EARLY EVENING.
FOCUS CONTINUES TO BE WITH TIMING OF VARIOUS MCS FEATURES THIS
WEEKEND. DEVELOPMENT ACROSS IOWA/MINNESOTA ON SUNDAY EXPECTED TO
EXTEND SOUTHWEST INTO MISSOURI...BUT ONLY THE NAM BRINGS ANY OF IT
THIS FAR EAST BY MONDAY MORNING. HAVE LIMITED ANY 30 PERCENT OR
HIGHER POPS TO THE FAR NORTHWEST LATE SUNDAY NIGHT... WITH MORE
WIDESPREAD CHANCES MONDAY. THE ECMWF AND CANADIAN MODELS SHOW THE
MCS SPREADING OVER THE FORECAST AREA... WHILE THE NAM AND GFS
SHUNT IT MORE TO THE NORTHEAST. SEVERE WEATHER POTENTIAL APPEARS
TO INCREASE BY MONDAY...MAINLY IN THE NORTHWEST CWA.
HAVE KEPT HIGH TEMPERATURES RIGHT AROUND 90 DEGREES FOR THE NEXT
FEW DAYS...WITH HEAT INDEX VALUES IN THE MID TO UPPER 90S. WILL
HAVE TO KEEP AN EYE ON HIGHS FOR MONDAY THOUGH...AS THEY COULD BE
LOWER IF THIS MCS DOES PAN OUT.
LONG TERM...TUESDAY THROUGH FRIDAY...
BROAD EAST-WEST RIDGE EXPECTED TO COVER THE SOUTH HALF OF THE
CONUS MUCH OF THE WEEK...WITH THE MAIN STORM TRACK ACROSS THE
NORTHERN STATES. MCS TRACKS REMAINS THE CONCERN AND ALTHOUGH MANY
OF THEM ARE FURTHER NORTH...LEFTOVER OUTFLOWS MAKE IT DIFFICULT TO
PIN DOWN ANY DRY PERIODS WITH ANY CERTAINTY. HIGHEST POPS FROM
WEDNESDAY NIGHT TO FRIDAY ARE TIED INTO PASSAGE OF A COLD FRONT...
WHICH MAY TAKE UNTIL EARLY FRIDAY TO FULLY PASS THE REGION AS THE
UPPER RIDGING BUILDS ACROSS THE ROCKIES AND PUTS THE MIDWEST MORE
OF A TROUGH. THIS PARTICULAR PATTERN WOULD SHOW THE HEAT FINALLY
BREAKING ON FRIDAY...WITH COOLER CONDITIONS NEXT WEEKEND.
GEELHART
&&
.AVIATION...
ISSUED 520 AM CDT SAT JUN 22 2013
COVERAGE OF TSRA AND THE AFFECTS ON CIGS/VSBYS THIS FORECAST PERIOD.
MID LEVEL MOISTURE HAS RAPIDLY DEVELOPED ACRS THE AREA THIS MORNING
IN ADVANCE OF A WEAK UPPER LEVEL DISTURBANCE COUPLED WITH SOME
ELEVATED INSTABILITY. JUST HOW MUCH SHOWER DEVELOPMENT TAKES PLACE
IS STILL IN QUESTION AHEAD OF THIS SYSTEM...BUT WILL COVER FOR NOW
WITH VCTS AND CONTINUE TO TRY TO PIN DOWN SOME BETTER TIMING OF
STORMS IN THE AFTN HOURS. STILL APPEARS THE COVERAGE SHOULD QUICKLY
DIMINISH JUST AFTR SUNSET THIS EVENING WITH MAIN MID AND HIGH LEVEL
MOISTURE REMAINING TONIGHT. IF SKIES SHOULD CLEAR OUT LATER TONIGHT
WE MAY HAVE TO DEAL WITH SOME PATCHY GROUND FOG...BUT FOR NOW WILL
LEAVE OUT OF TAFS. SFC WINDS WILL REMAIN OUT OF A SSW (180-210)
DIRECTION THRU THIS FORECAST PERIOD. SPEEDS WILL RANGE FROM 10 TO
15 KTS TODAY WITH A FEW GUSTS IN THE 15 TO 20 KT RANGE AND THEN
DIMINISH TO AROUND 10 KTS THIS EVENING.
SMITH
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
252 AM CDT SAT JUN 22 2013
.DISCUSSION...
ISSUED 250 AM CDT SAT JUN 22 2013
2 AM SATELLITE IMAGERY AND RADAR DATA SHOWING A PAIR OF MCS
SYSTEMS MERGING FROM SOUTH DAKOTA EASTWARD INTO SOUTHERN
WISCONSIN. EASTERN END OF THE LINE OF STORMS HAS MADE A SOUTHWARD
PUSH INTO NORTHEAST ILLINOIS...WITH THIS PART OF THE MCS BECOMING
THE DOMINANT ONE AS LIGHTNING DIMINISHES OVER SOUTHERN MINNESOTA.
LINGERING BOUNDARY FROM THE STORMS IN OUR AREA YESTERDAY WRAPS
AROUND THE SOUTHWEST AND SOUTHEAST PARTS OF THE FORECAST AREA.
STILL SEEING A FEW SPRINKLES IN THE FAR SOUTHEAST CWA WITH THIS
BOUNDARY.
FORECAST CHALLENGES FOR THIS PACKAGE GENERALLY REVOLVE AROUND
TIMING OF THUNDERSTORM CHANCES...AS WELL AS THE ONGOING HEAT AND
HUMIDITY.
SHORT TERM...TODAY THROUGH MONDAY...
MODELS ARE STRUGGLING TO GET A HANDLE ON THE CURRENT SITUATION...
WITH THE HRRR AND THE REGIONAL CANADIAN MODEL CLOSEST TO REALITY.
NEITHER OF THESE MODELS SHOW THE STORMS MAKING IT AS FAR SOUTH AS
OUR FORECAST AREA...BUT AS THE MCS FROM YESTERDAY SHOWED...THAT
OUTCOME IS DEFINITELY NOT GUARANTEED. WILL INCLUDE SOME ISOLATED
THUNDERSTORM MENTION IN THE NORTHEAST THIRD OF THE CWA THIS
MORNING...BETWEEN THIS LINE AND POTENTIALLY SOME DEVELOPMENT ALONG
THE OUTFLOW BOUNDARY...WITH AROUND 30 PERCENT CHANCES ACROSS THE
NORTHEAST DURING THE AFTERNOON. HAVE MENTIONED ISOLATED STORMS
ELSEWHERE THIS AFTERNOON AND EARLY EVENING.
FOCUS CONTINUES TO BE WITH TIMING OF VARIOUS MCS FEATURES THIS
WEEKEND. DEVELOPMENT ACROSS IOWA/MINNESOTA ON SUNDAY EXPECTED TO
EXTEND SOUTHWEST INTO MISSOURI...BUT ONLY THE NAM BRINGS ANY OF IT
THIS FAR EAST BY MONDAY MORNING. HAVE LIMITED ANY 30 PERCENT OR
HIGHER POPS TO THE FAR NORTHWEST LATE SUNDAY NIGHT... WITH MORE
WIDESPREAD CHANCES MONDAY. THE ECMWF AND CANADIAN MODELS SHOW THE
MCS SPREADING OVER THE FORECAST AREA... WHILE THE NAM AND GFS
SHUNT IT MORE TO THE NORTHEAST. SEVERE WEATHER POTENTIAL APPEARS
TO INCREASE BY MONDAY...MAINLY IN THE NORTHWEST CWA.
HAVE KEPT HIGH TEMPERATURES RIGHT AROUND 90 DEGREES FOR THE NEXT
FEW DAYS...WITH HEAT INDEX VALUES IN THE MID TO UPPER 90S. WILL
HAVE TO KEEP AN EYE ON HIGHS FOR MONDAY THOUGH...AS THEY COULD BE
LOWER IF THIS MCS DOES PAN OUT.
LONG TERM...TUESDAY THROUGH FRIDAY...
BROAD EAST-WEST RIDGE EXPECTED TO COVER THE SOUTH HALF OF THE
CONUS MUCH OF THE WEEK...WITH THE MAIN STORM TRACK ACROSS THE
NORTHERN STATES. MCS TRACKS REMAINS THE CONCERN AND ALTHOUGH MANY
OF THEM ARE FURTHER NORTH...LEFTOVER OUTFLOWS MAKE IT DIFFICULT TO
PIN DOWN ANY DRY PERIODS WITH ANY CERTAINTY. HIGHEST POPS FROM
WEDNESDAY NIGHT TO FRIDAY ARE TIED INTO PASSAGE OF A COLD FRONT...
WHICH MAY TAKE UNTIL EARLY FRIDAY TO FULLY PASS THE REGION AS THE
UPPER RIDGING BUILDS ACROSS THE ROCKIES AND PUTS THE MIDWEST MORE
OF A TROUGH. THIS PARTICULAR PATTERN WOULD SHOW THE HEAT FINALLY
BREAKING ON FRIDAY...WITH COOLER CONDITIONS NEXT WEEKEND.
GEELHART
&&
.AVIATION...
ISSUED 1154 PM CDT FRI JUN 21 2013
MAIN ISSUE FOR THE TAFS REMAINS THE NEXT ROUND OF CONVECTION AND
THAT LACK OF CONFIDENCE IN ANY MODEL OUTPUT HELPING WITH THE CALL.
GFS REMAINS STORMY IN THE SHORT TERM...AND DRY TOMORROW AFTERNOON.
WHILE THE NAM/WRF IS MORE FOCUSED ON SHOWERS AND THUNDERSTORMS
FROM MID MORNING ON THROUGH THE AFTERNOON. HAVE TRIED TO SPLIT THE
DIFFERENCE IN THE CURRENT FORECAST WITH A NOD TO PERSISTENCE AND
YESTERDAYS MCS. BEST CHANCES FOR TSRA IN THE AFTERNOON. SOUTHERLY
WINDS DOMINATE...AS WELL AS VFR...THOUGH OBVIOUSLY A DROP IN TS
ACTIVITY. TIMING AND COVERAGE CONFIDENCE LOWER THAN NORMAL.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1158 PM CDT FRI JUN 21 2013
.DISCUSSION...
ISSUED 915 PM CDT FRI JUN 21 2013
WITH THE REMAINS OF THE DYING MCS MOVING OUT OF THE STATE TO THE
EAST/SE...PULLING POPS IN THE OVERNIGHT FOR THE AREA. KEEPING SOME
SLIGHTS IN THE EAST FOR ANY REDEVELOPMENT...BUT THE SYSTEM IS
PULLING TOO FAR TO THE EAST AND THE CURRENT RUC/RAPP RUN IS MOSTLY
DRY IN THE OVERNIGHT. ONLY CONCERN FOR THE OVERNIGHT IS THE
POTENTIAL FOR PATCHY FOG WITH THE MOISTURE IN THE BOUNDARY LAYER
DUE TO THE STORMS. BUT THE DWPTS ARE ACTUALLY LOWER IN THE AREAS
THAT SAW RAIN...AND WELL BELOW THE EXPECTED LOWS. WILL CONTINUE
TO MONITOR...UPDATES OUT MOMENTARILY.
&&
.AVIATION...
ISSUED 1154 PM CDT FRI JUN 21 2013
MAIN ISSUE FOR THE TAFS REMAINS THE NEXT ROUND OF CONVECTION AND
THAT LACK OF CONFIDENCE IN ANY MODEL OUTPUT HELPING WITH THE CALL.
GFS REMAINS STORMY IN THE SHORT TERM...AND DRY TOMORROW AFTERNOON.
WHILE THE NAM/WRF IS MORE FOCUSED ON SHOWERS AND THUNDERSTORMS
FROM MIDMORNING ON THROUGH THE AFTERNOON. HAVE TRIED TO SPLIT THE
DIFFERENCE IN THE CURRENT FORECAST WITH A NOD TO PERSISTENCE AND
YESTERDAYS MCS. BEST CHANCES FOR TSRA IN THE AFTERNOON. SOUTHERLY
WINDS DOMINATE...AS WELL AS VFR...THOUGH OBVIOUSLY A DROP IN TS
ACTIVITY. TIMING AND COVERAGE CONFIDENCE LOWER THAN NORMAL.
HJS
&&
.PREV DISCUSSION...
ISSUED 300 PM CDT FRI JUN 21 2013
INITIAL CONCERNS WILL FOCUS ON THE SEVERE POTENTIAL WITH THE LINE
OF STORMS MOVING ACROSS OUR NORTHERN COUNTIES. THEN ATTENTION
TURNS TO THE HEAT AND HUMIDITY WITH PERIODIC STORM CHANCES IN THIS
SUMMER PATTERN. THE EXTENDED FORECAST STILL CALLS FOR OUR NEXT
COLD FRONT TO ARRIVE AROUND THURSDAY.
SHORT TERM...TONIGHT THROUGH MONDAY.
A 30-40 MPH SOUTHWARD MOVING GUST FRONT IS GENERALLY OUTRUNNING
THE LINE OF STORMS BY 5 TO 10 MILES IN MOST AREAS...EXCEPT FOR IN
THE MID-PORTION OF THE LINE FROM DELAVAN TO BLOOMINGTON. STORM
INITIATION REMAINS CLOSER TO THE GUST FRONT IN THAT AREA. THOSE
STORMS ARE THE STRONGEST AT 230 PM...BUT STILL APPEAR TO BE SUB-
SEVERE. HAIL AND WIND REPORTS HAVE BEEN SPARSE, BUT A FEW TREE LIMBS
MAY HAVE BEEN KNOCKED DOWN NEAR DUNLAP AND THE LARGEST HAIL REPORT
WAS DIME SIZED 1N OF MOSSVILLE EARLIER. STORM INTENSITY HAS
GENERALLY WEAKENED SINCE THOSE REPORTS...SO WE CONTINUE TO MONITOR
FOR ANY INTENSIFICATION. SPC MESO-ANALYSIS PAGE SHOWS MORE STABLE
AIR AHEAD OF THE STORMS...WITH WEAKER 0-6KM BULK SHEAR. THERE IS
STILL 1500 J/KG MUCAPE AVAILABLE...SO THE STORMS MAY LINGER AT
LEAST UNTIL THE INDIANA BORDER EARLY THIS EVENING.
INTO EARLY EVENING...A COUPLE 4KM MODELS ARE SHOWING ADDITIONAL
STORM DEVELOPMENT FARTHER WEST IN EASTERN IOWA/NE MO WHERE
INSTABILITY AND SHEAR PARAMS ARE MORE FAVORABLE FOR STORMS.
HOWEVER...THE 18Z HRRR RUN DOES NOT HAVE ANY INDICATION OF THOSE
STORMS. TAKING EVERYTHING INTO CONSIDERATION...WE TRIED TO MAKE
THE POPS/WEATHER GRIDS CONFORM CLOSELY TO THE NEXT 3-5 HOURS OF
CONVECTION...THEN WENT MORE GENERAL BASED ON SATELLITE, RADAR AND
OBSERVATION TRENDS. WE LINGERED SOME HIGHER POPS THROUGH 03Z THIS
EVENING IN THE EAST TO TREND THE CURRENT STORMS EASTWARD...WITH
SLIGHT CHANCE IN OUR WESTERN COUNTIES TO COVER THE NEXT LINE THAT
MAY ARRIVE.
THE REST OF THE NIGHT SHOULD BE MUGGY AND MILD...AS CLOUDS CLEAR
OUT AND LINGERING NORTH WINDS BEHIND THIS LINE OF STORMS RETURNS
TO SOUTHERLY.
SATURDAY WILL BRING ANOTHER ROUND OF AFTERNOON SHOWERS AND STORMS
AS HIGHS CLIMB INTO THE LOWER 90S AND HEAT INDICES REACH AROUND
100. SEVERE CHANCES SHOULD REMAIN LOW IN OUR COUNTIES...WITH THE
SLIGHT RISK FOR DAY 2 NW OF ILLINOIS. THE TRIGGERS FOR STORMS MAY
BE TIED TO THE RESIDUAL OUTFLOW BOUNDARIES FROM TODAY`S
CONVECTION...AND THE PASSAGE OF A WEAK 500 MB SHORTWAVE.
PRECIPITABLE WATER VALUES AROUND 1.75" WILL ALLOW SOME OF THE
STRONGER STORMS TO BE VERY HEAVY RAIN PRODUCERS...WITH RAINFALL
RATES OF 1-2" PER HOUR. LOCALIZED FLASH FLOODING WILL BE
POSSIBLE...DESPITE THE RELATIVELY DRY CONDITIONS OVER THE PAST
COUPLE OF WEEKS IN MOST AREAS. STORMS SHOULD COME TO AN END BY
SATURDAY EVENING...WITH CLEARING SKIES OVERNIGHT.
SUNDAY WILL SEE LESS FAVORABLE INSTABILITY PARAMS...AS MID LEVEL
WARMING PROVIDES A BETTER CAP ON STORM DEVELOPMENT. WE KEPT A DRY
FORECAST FOR SUNDAY...BUT KEPT THE HEAT AND HUMIDITY HIGH. HEAT
INDEX READING SHOULD REMAIN BELOW SATURDAYS READINGS...BUT STILL
IN THE MID TO UPPER 90S.
MONDAY WILL SEE THE RETURN OF STORM CHANCES AS THE NEXT 500MB
SHORTWAVE CREATES SOME FALLING HEIGHTS AND DESTABILIZES THE LOWER
TROPOSPHERE. STORM DEVELOPMENT SHOULD OCCUR IN THE AFTERNOON...AS
SURFACE HEATING HELPS TO ERODE THE CAP. WE WENT WITH CHANCE POPS
IN THE NW HALF OF OUR FORECAST AREA...WITH SLIGHTS DOWN TO I-70.
LONG TERM...TUESDAY THROUGH FRIDAY.
ANOTHER LULL IN THE STORMS IS EXPECTED MONDAY NIGHT THRU TUESDAY
NIGHT...AS THE UPPER TROUGH IN THE N PLAINS BEGINS TO BECOME
PROGRESSIVE. AS THE UPPER TROUGH REACHES THE GREAT LAKES...A
SURFACE COLD FRONT IS FORECAST TO MOVE ACROSS ILLINOIS ON THURSDAY
OR THURSDAY NIGHT. SHOWERS AND STORMS WILL LIKELY DEVELOP ALONG
THAT FEATURE...DESPITE THE WEAKER APPEARANCE OF THE FRONT IN THE
EXTENDED MODELS.
THE NORTHWEST FLOW BEHIND THAT COLD FRONT WILL HELP DROP HIGHS
FROM THE LOW 90S ON TUESDAY AND WED...BACK INTO THE UPPER 80S
THURSDAY AND LOWER 80S ON FRIDAY. DEWPOINTS WILL DROP INTO THE
LOWER 60S ON FRIDAY AS WELL...PROVIDING SOME RELIEF FROM THE HEAT
AND HUMIDITY.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
553 AM EDT SAT JUN 22 2013
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 307 AM EDT SAT JUN 22 2013
POTENTIAL EXISTS FOR OCCASIONAL UPPER DISTURBANCES...RIDING ALONG
THE EDGE OF AN UPPER RIDGE...TO AFFECT CENTRAL INDIANA INTO THE
MIDDLE OF NEXT WEEK. BY NEXT THURSDAY AND FRIDAY...A COLD FRONT MAY
MOVE INTO THE AREA.
&&
.NEAR TERM /TODAY/...
ISSUED AT 307 AM EDT SAT JUN 22 2013
CONFIDENCE IS LOW IN THE THUNDERSTORM FORECAST FOR THIS WEEKEND.
NONE OF THE MODELS APPEAR TO HAVE A HANDLE ON THE MCS CURRENTLY OVER
MN AND WI. THE HRRR MAY BE THE ONLY MODEL TO PROVIDE SOME TRUTH TO
WHAT WILL PREVAIL FOR LATER TODAY...AND THAT IS THE POTENTIAL FOR
REMNANT MCS ACTIVITY TO EVENTUALLY WORK IT/S WAY SOUTH TO CENTRAL
INDIANA BY THIS AFTERNOON AND EARLY EVENING. INCREASED POP COVERAGE
TO INCLUDE THE ENTIRE CWA...WITH SLIGHTLY HIGHER CHANCE POPS ACROSS
THE NORTHERN TIER WHERE ANY REMNANT ACTIVITY IS MOSTLY LIKELY TO
REACH.
IF THIS ACTIVITY DOES REACH CENTRAL INDIANA BY THIS AFTERNOON THEN
TEMPERATURES WILL BE AFFECTED. SINCE CONFIDENCE IS LOW AT THIS
JUNCTURE WILL CONTINUE WITH PERSISTENCE AND WARM HIGHS IN THE UPPER
80S TO AROUND 90.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
ISSUED AT 307 AM EDT SAT JUN 22 2013
SLIGHT CHANCE TO LOW CHANCE POPS WILL CONTINUE THIS EVENING AND THEN
BY 06Z BE DRY. LOWS AROUND 70. SUNDAY AND MONDAY WILL BRING WITH IT
SIMILAR CHALLENGES TO THE THUNDERSTORM FORECAST AS A FEW UPPER LEVEL
DISTURBANCES ARE FORECAST TO MOVE THROUGH. INTRODUCED AT LEAST A
SLIGHT CHANCE POP FOR SUNDAY AFTERNOON...AND AGAIN MONDAY AND
MONDAY NIGHT.
THE OTHER STORY THROUGH AT LEAST MID WEEK WILL BE THE SEASONABLY WARM
TEMPERATURES WITH HIGHS REACHING AROUND THE 90 MARK. DID NOT STRAY
FAR FROM MOS.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
ISSUED AT 315 AM EDT SAT JUN 22 2013
A FAIRLY TYPICAL SUMMERTIME PATTERN WILL SET UP DURING THE EARLY TO
MIDDLE PORTION OF THE WORK WEEK WITH ZONAL FLOW TO WEAK RIDGING
ALOFT AND BROAD SOUTH TO SOUTHWEST FLOW NEAR THE SURFACE. CANNOT
RULE OUT ISOLATED AFTERNOON THUNDERSTORMS UNDER THIS REGIME TUESDAY
AND WEDNESDAY...ALTHOUGH CAPPING MAY BE A HINDRANCE...OTHERWISE
EXPECT MAINLY DRY CONDITIONS EARLY WEEK. THINGS DO TRANSITION LATE
WEEK WITH A MORE POTENT UPPER WAVE AND SURFACE SYSTEM MOVING THROUGH
THE AREA WEDNESDAY NIGHT INTO EARLY FRIDAY. HIGHER POPS WILL BE
NECESSARY HERE.
ON TEMPS...ALLBLEND INITIALIZATION WAS REASONABLE...ALTHOUGH DID
BUMP HIGHS UP A DEGREE IN SOME PERIODS TO ACCOUNT FOR POTENTIAL
IMPACT OF OVERDONE PRECIP IN MODELS. MAXES/MINS WILL BE NEAR TO A
BIT ABOVE CLIMO UNTIL VERY LATE IN THE PERIOD POST COLD FRONT...AS
THE ZONAL TO WEAKLY ANTICYCLONIC PATTERN WOULD DICTATE.
&&
.AVIATION /DISCUSSION FOR THE 22/12Z TAFS/...
ISSUED AT 553 AM EDT SAT JUN 22 2013
VFR THROUGH THE PERIOD.
SCT TO BKN MID TO HIGH LEVEL CLOUD ACROSS THE AREA THIS
MORNING...DEBRIS FROM YESTERDAYS STORMS AND FROM UPSTREAM CONVECTION
OVER NORTHERN ILLINOIS. EXPECT DEVELOPMENT OF BKN VFR CUMULUS
TODAY...AND THUNDERSTORMS WILL BE POSSIBLE...BUT TOO LOW PROBABILITY
AND TOO UNCERTAIN TO INCLUDE IN TAF AT THIS TIME. BEST TIME WOULD
ONCE AGAIN BE AFTERNOON INTO EVENING HOURS.
WINDS WILL BE 10KT OR LESS THROUGHOUT THE PERIOD...GENERALLY FROM
180-220 DEGREES.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF
SHORT TERM...SMF
LONG TERM....NIELD
AVIATION...NIELD
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
429 AM EDT SAT JUN 22 2013
.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 307 AM EDT SAT JUN 22 2013
POTENTIAL EXISTS FOR OCCASIONAL UPPER DISTURBANCES...RIDING ALONG
THE EDGE OF AN UPPER RIDGE...TO AFFECT CENTRAL INDIANA INTO THE
MIDDLE OF NEXT WEEK. BY NEXT THURSDAY AND FRIDAY...A COLD FRONT MAY
MOVE INTO THE AREA.
&&
.NEAR TERM /TODAY/...
ISSUED AT 307 AM EDT SAT JUN 22 2013
CONFIDENCE IS LOW IN THE THUNDERSTORM FORECAST FOR THIS WEEKEND.
NONE OF THE MODELS APPEAR TO HAVE A HANDLE ON THE MCS CURRENTLY OVER
MN AND WI. THE HRRR MAY BE THE ONLY MODEL TO PROVIDE SOME TRUTH TO
WHAT WILL PREVAIL FOR LATER TODAY...AND THAT IS THE POTENTIAL FOR
REMNANT MCS ACTIVITY TO EVENTUALLY WORK IT/S WAY SOUTH TO CENTRAL
INDIANA BY THIS AFTERNOON AND EARLY EVENING. INCREASED POP COVERAGE
TO INCLUDE THE ENTIRE CWA...WITH SLIGHTLY HIGHER CHANCE POPS ACROSS
THE NORTHERN TIER WHERE ANY REMNANT ACTIVITY IS MOSTLY LIKELY TO
REACH.
IF THIS ACTIVITY DOES REACH CENTRAL INDIANA BY THIS AFTERNOON THEN
TEMPERATURES WILL BE AFFECTED. SINCE CONFIDENCE IS LOW AT THIS
JUNCTURE WILL CONTINUE WITH PERSISTENCE AND WARM HIGHS IN THE UPPER
80S TO AROUND 90.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
ISSUED AT 307 AM EDT SAT JUN 22 2013
SLIGHT CHANCE TO LOW CHANCE POPS WILL CONTINUE THIS EVENING AND THEN
BY 06Z BE DRY. LOWS AROUND 70. SUNDAY AND MONDAY WILL BRING WITH IT
SIMILAR CHALLENGES TO THE THUNDERSTORM FORECAST AS A FEW UPPER LEVEL
DISTURBANCES ARE FORECAST TO MOVE THROUGH. INTRODUCED AT LEAST A
SLIGHT CHANCE POP FOR SUNDAY AFTERNOON...AND AGAIN MONDAY AND
MONDAY NIGHT.
THE OTHER STORY THROUGH AT LEAST MID WEEK WILL BE THE SEASONABLY WARM
TEMPERATURES WITH HIGHS REACHING AROUND THE 90 MARK. DID NOT STRAY
FAR FROM MOS.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
ISSUED AT 315 AM EDT SAT JUN 22 2013
A FAIRLY TYPICAL SUMMERTIME PATTERN WILL SET UP DURING THE EARLY TO
MIDDLE PORTION OF THE WORK WEEK WITH ZONAL FLOW TO WEAK RIDGING
ALOFT AND BROAD SOUTH TO SOUTHWEST FLOW NEAR THE SURFACE. CANNOT
RULE OUT ISOLATED AFTERNOON THUNDERSTORMS UNDER THIS REGIME TUESDAY
AND WEDNESDAY...ALTHOUGH CAPPING MAY BE A HINDRANCE...OTHERWISE
EXPECT MAINLY DRY CONDITIONS EARLY WEEK. THINGS DO TRANSITION LATE
WEEK WITH A MORE POTENT UPPER WAVE AND SURFACE SYSTEM MOVING THROUGH
THE AREA WEDNESDAY NIGHT INTO EARLY FRIDAY. HIGHER POPS WILL BE
NECESSARY HERE.
ON TEMPS...ALLBLEND INITIALIZATION WAS REASONABLE...ALTHOUGH DID
BUMP HIGHS UP A DEGREE IN SOME PERIODS TO ACCOUNT FOR POTENTIAL
IMPACT OF OVERDONE PRECIP IN MODELS. MAXES/MINS WILL BE NEAR TO A
BIT ABOVE CLIMO UNTIL VERY LATE IN THE PERIOD POST COLD FRONT...AS
THE ZONAL TO WEAKLY ANTICYCLONIC PATTERN WOULD DICTATE.
&&
.AVIATION /DISCUSSION FOR THE 22/09Z TAF UPDATE/...
ISSUED AT 429 AM EDT SAT JUN 22 2013
NO SIGNIFICANT CHANGES NECESSARY. PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 1213 AM EDT SAT JUN 22 2013
EXPECT MOSTLY VFR CONDITIONS EXCEPT PERHAPS SOME BRIEF OVERNIGHT FOG
TONIGHT AT LAF AND MORESO AT HUF WHERE OVER AN INCH OF RAIN FELL
LAST EVENING. HOWEVER...THINK THERE IS A BETTER CHANCE THAT
CONVECTIVE DEBRIS CLOUDS WILL BE SUFFICIENT TO KEEP THE VISIBILITY
P6SM ESPECIALLY AT LAF. COULD SEE A FEW MORE AFTERNOON STORMS MAINLY
AFTER 16Z...BUT CHANCES TOO SMALL TO MENTION. DID GO WITH A BROKEN
VFR CU DECK THOUGH TO STRESS CONVECTIVE POSSIBILITY.
SOUTH AND SOUTHWEST 7 KNOTS OR LESS TONIGHT WILL INCREASE TO AROUND
10 KNOTS FROM THE SOUTHWEST AFTER 16Z SATURDAY AND BECOME LIGHT TO
CALM AFTER 02Z SUNDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF
SHORT TERM...SMF
LONG TERM....NIELD
AVIATION...MK/NIELD
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
315 AM EDT SAT JUN 22 2013
.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 307 AM EDT SAT JUN 22 2013
POTENTIAL EXISTS FOR OCCASIONAL UPPER DISTURBANCES...RIDING ALONG
THE EDGE OF AN UPPER RIDGE...TO AFFECT CENTRAL INDIANA INTO THE
MIDDLE OF NEXT WEEK. BY NEXT THURSDAY AND FRIDAY...A COLD FRONT MAY
MOVE INTO THE AREA.
&&
.NEAR TERM /TODAY/...
ISSUED AT 307 AM EDT SAT JUN 22 2013
CONFIDENCE IS LOW IN THE THUNDERSTORM FORECAST FOR THIS WEEKEND.
NONE OF THE MODELS APPEAR TO HAVE A HANDLE ON THE MCS CURRENTLY OVER
MN AND WI. THE HRRR MAY BE THE ONLY MODEL TO PROVIDE SOME TRUTH TO
WHAT WILL PREVAIL FOR LATER TODAY...AND THAT IS THE POTENTIAL FOR
REMNANT MCS ACTIVITY TO EVENTUALLY WORK IT/S WAY SOUTH TO CENTRAL
INDIANA BY THIS AFTERNOON AND EARLY EVENING. INCREASED POP COVERAGE
TO INCLUDE THE ENTIRE CWA...WITH SLIGHTLY HIGHER CHANCE POPS ACROSS
THE NORTHERN TIER WHERE ANY REMNANT ACTIVITY IS MOSTLY LIKELY TO
REACH.
IF THIS ACTIVITY DOES REACH CENTRAL INDIANA BY THIS AFTERNOON THEN
TEMPERATURES WILL BE AFFECTED. SINCE CONFIDENCE IS LOW AT THIS
JUNCTURE WILL CONTINUE WITH PERSISTENCE AND WARM HIGHS IN THE UPPER
80S TO AROUND 90.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
ISSUED AT 307 AM EDT SAT JUN 22 2013
SLIGHT CHANCE TO LOW CHANCE POPS WILL CONTINUE THIS EVENING AND THEN
BY 06Z BE DRY. LOWS AROUND 70. SUNDAY AND MONDAY WILL BRING WITH IT
SIMILAR CHALLENGES TO THE THUNDERSTORM FORECAST AS A FEW UPPER LEVEL
DISTURBANCES ARE FORECAST TO MOVE THROUGH. INTRODUCED AT LEAST A
SLIGHT CHANCE POP FOR SUNDAY AFTERNOON...AND AGAIN MONDAY AND
MONDAY NIGHT.
THE OTHER STORY THROUGH AT LEAST MID WEEK WILL BE THE SEASONABLY WARM
TEMPERATURES WITH HIGHS REACHING AROUND THE 90 MARK. DID NOT STRAY
FAR FROM MOS.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
ISSUED AT 315 AM EDT SAT JUN 22 2013
A FAIRLY TYPICAL SUMMERTIME PATTERN WILL SET UP DURING THE EARLY TO
MIDDLE PORTION OF THE WORK WEEK WITH ZONAL FLOW TO WEAK RIDGING
ALOFT AND BROAD SOUTH TO SOUTHWEST FLOW NEAR THE SURFACE. CANNOT
RULE OUT ISOLATED AFTERNOON THUNDERSTORMS UNDER THIS REGIME TUESDAY
AND WEDNESDAY...ALTHOUGH CAPPING MAY BE A HINDRANCE...OTHERWISE
EXPECT MAINLY DRY CONDITIONS EARLY WEEK. THINGS DO TRANSITION LATE
WEEK WITH A MORE POTENT UPPER WAVE AND SURFACE SYSTEM MOVING THROUGH
THE AREA WEDNESDAY NIGHT INTO EARLY FRIDAY. HIGHER POPS WILL BE
NECESSARY HERE.
ON TEMPS...ALLBLEND INITIALIZATION WAS REASONABLE...ALTHOUGH DID
BUMP HIGHS UP A DEGREE IN SOME PERIODS TO ACCOUNT FOR POTENTIAL
IMPACT OF OVERDONE PRECIP IN MODELS. MAXES/MINS WILL BE NEAR TO A
BIT ABOVE CLIMO UNTIL VERY LATE IN THE PERIOD POST COLD FRONT...AS
THE ZONAL TO WEAKLY ANTICYCLONIC PATTERN WOULD DICTATE.
&&
.AVIATION /DISCUSSION FOR THE 22/06Z TAFS/...
ISSUED AT 1213 AM EDT SAT JUN 22 2013
EXPECT MOSTLY VFR CONDITIONS EXCEPT PERHAPS SOME BRIEF OVERNIGHT FOG
TONIGHT AT LAF AND MORESO AT HUF WHERE OVER AN INCH OF RAIN FELL
LAST EVENING. HOWEVER...THINK THERE IS A BETTER CHANCE THAT
CONVECTIVE DEBRIS CLOUDS WILL BE SUFFICIENT TO KEEP THE VISIBILITY
P6SM ESPECIALLY AT LAF. COULD SEE A FEW MORE AFTERNOON STORMS MAINLY
AFTER 16Z...BUT CHANCES TOO SMALL TO MENTION. DID GO WITH A BROKEN
VFR CU DECK THOUGH TO STRESS CONVECTIVE POSSIBILITY.
SOUTH AND SOUTHWEST 7 KNOTS OR LESS TONIGHT WILL INCREASE TO AROUND
10 KNOTS FROM THE SOUTHWEST AFTER 16Z SATURDAY AND BECOME LIGHT TO
CALM AFTER 02Z SUNDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF
SHORT TERM...SMF
LONG TERM....NIELD
AVIATION...MK
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
310 AM EDT SAT JUN 22 2013
.UPDATE...
THE SYNOPSIS...NEAR TERM AND SHORT TERM SECTIONS HAVE BEEN UPDATED
BELOW.
&&
.SYNOPSIS...
ISSUED AT 307 AM EDT SAT JUN 22 2013
POTENTIAL EXISTS FOR OCCASIONAL UPPER DISTURBANCES...RIDING ALONG
THE EDGE OF AN UPPER RIDGE...TO AFFECT CENTRAL INDIANA INTO THE
MIDDLE OF NEXT WEEK. BY NEXT THURSDAY AND FRIDAY...A COLD FRONT MAY
MOVE INTO THE AREA.
&&
.NEAR TERM /TODAY/...
ISSUED AT 307 AM EDT SAT JUN 22 2013
CONFIDENCE IS LOW IN THE THUNDERSTORM FORECAST FOR THIS WEEKEND.
NONE OF THE MODELS APPEAR TO HAVE A HANDLE ON THE MCS CURRENTLY OVER
MN AND WI. THE HRRR MAY BE THE ONLY MODEL TO PROVIDE SOME TRUTH TO
WHAT WILL PREVAIL FOR LATER TODAY...AND THAT IS THE POTENTIAL FOR
REMNANT MCS ACTIVITY TO EVENTUALLY WORK IT/S WAY SOUTH TO CENTRAL
INDIANA BY THIS AFTERNOON AND EARLY EVENING. INCREASED POP COVERAGE
TO INCLUDE THE ENTIRE CWA...WITH SLIGHTLY HIGHER CHANCE POPS ACROSS
THE NORTHERN TIER WHERE ANY REMNANT ACTIVITY IS MOSTLY LIKELY TO
REACH.
IF THIS ACTIVITY DOES REACH CENTRAL INDIANA BY THIS AFTERNOON THEN
TEMPERATURES WILL BE AFFECTED. SINCE CONFIDENCE IS LOW AT THIS
JUNCTURE WILL CONTINUE WITH PERSISTENCE AND WARM HIGHS IN THE UPPER
80S TO AROUND 90.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
ISSUED AT 307 AM EDT SAT JUN 22 2013
SLIGHT CHANCE TO LOW CHANCE POPS WILL CONTINUE THIS EVENING AND THEN
BY 06Z BE DRY. LOWS AROUND 70. SUNDAY AND MONDAY WILL BRING WITH IT
SIMILAR CHALLENGES TO THE THUNDERSTORM FORECAST AS A FEW UPPER LEVEL
DISTURBANCES ARE FORECAST TO MOVE THROUGH. INTRODUCED AT LEAST A
SLIGHT CHANCE POP FOR SUNDAY AFTERNOON...AND AGAIN MONDAY AND
MONDAY NIGHT.
THE OTHER STORY THROUGH AT LEAST MID WEEK WILL BE THE SEASONABLY WARM
TEMPERATURES WITH HIGHS REACHING AROUND THE 90 MARK. DID NOT STRAY
FAR FROM MOS.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
ISSUED AT 242 PM EDT FRI JUN 21 2013
SUMMER TIME PATTERN WILL BE IN PLACE FOR THE BEGINNING OF LONG TERM
PERIOD. WEAK RIDGING ALOFT AND SOUTH/SOUTHWEST FLOW AT THE SURFACE
WILL BE CONDUCIVE TO PERIODS OF DIURNALLY DRIVEN SHOWERS AND
THUNDERSTORMS. HOWEVER...CHANCES FOR SHOWERS AND THUNDERSTORMS
WILL INCREASE LATER IN THE WEEK /MAINLY THURSDAY/ AS AN UPPER LEVEL
LOW TRAVERSES ONTARIO...AND ITS TRAILING COLD FRONT SWEEPS ACROSS
CENTRAL INDIANA.
TEMPS...FELT THAT LATEST INITIALIZATION WAS ON THE COOL SIDE FOR
WARM SOUTHWEST FLOW AT THE SURFACE ON TUESDAY AND WEDNESDAY. AS A
RESULT...TRENDED 1 TO 3 DEGREES ABOVE GUIDANCE FOR DAYTIME HIGHS ON
THOSE DAYS. OTHERWISE...WAS ABLE TO STICK CLOSE TO ALLBLEND
INITIALIZATION NUMBERS FOR THE REMAINDER OF THE EXTENDED PERIOD.
&&
.AVIATION /DISCUSSION FOR THE 22/06Z TAFS/...
ISSUED AT 1213 AM EDT SAT JUN 22 2013
EXPECT MOSTLY VFR CONDITIONS EXCEPT PERHAPS SOME BRIEF OVERNIGHT FOG
TONIGHT AT LAF AND MORESO AT HUF WHERE OVER AN INCH OF RAIN FELL
LAST EVENING. HOWEVER...THINK THERE IS A BETTER CHANCE THAT
CONVECTIVE DEBRIS CLOUDS WILL BE SUFFICIENT TO KEEP THE VISIBILITY
P6SM ESPECIALLY AT LAF. COULD SEE A FEW MORE AFTERNOON STORMS MAINLY
AFTER 16Z...BUT CHANCES TOO SMALL TO MENTION. DID GO WITH A BROKEN
VFR CU DECK THOUGH TO STRESS CONVECTIVE POSSIBILITY.
SOUTH AND SOUTHWEST 7 KNOTS OR LESS TONIGHT WILL INCREASE TO AROUND
10 KNOTS FROM THE SOUTHWEST AFTER 16Z SATURDAY AND BECOME LIGHT TO
CALM AFTER 02Z SUNDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF
SHORT TERM...SMF
LONG TERM....TDUD
AVIATION...MK
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS WICHITA KS
306 PM CDT SAT JUN 22 2013
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 306 PM CDT SAT JUN 22 2013
FORECAST HIGHLIGHTS FOCUS AROUND HOT AND WINDY WEATHER CONTINUING
THROUGH MID WEEK...THUNDERSTORM CHANCES LATE SUN AFTERNOON-NIGHT
OVER CENTRAL KS AND AGAIN THU-THU NIGHT AREAWIDE...AND A COOLING
TREND BY LATE WEEK/NEXT WEEKEND.
APPROACHING SHORTWAVE ENERGY SHOULD INITIATE A FEW THUNDERSTORMS
OVER WESTERN KS LATE THIS AFTERNOON ALONG A SHARPENING DRYLINE. LAST
3 RUNS OF THE HRRR HAVE ALLUDED TO THIS. NOT OUT OF THE REALM OF
POSSIBILITY THAT SOME OF THIS ACTIVITY COULD GET INTO RUSSELL AND
BARTON COUNTIES BETWEEN 8 PM AND MIDNIGHT. HOWEVER...SUSPECT WEAK
FORCING IN CONCERT WITH WARM MID-LEVEL TEMPERATURES/INCREASING CINH
WILL LIKELY DISSIPATE THIS ACTIVITY BEFORE REACHING WESTERN
CORRIDOR. ADDITIONAL ACTIVITY WILL LIKELY AFFECT NEBRASKA AND
POSSIBLY FAR NORTHERN KS OVERNIGHT...BUT WILL LIKELY REMAIN NORTH OF
THE FORECAST AREA.
OTHERWISE...SHORTWAVE ENERGY PROGRESSING ACROSS THE NORTHERN PLAINS
WILL ALLOW A COLD FRONT TO APPROACH CENTRAL KS SUNDAY. THE INCREASED
CONVERGENCE AT PEAK HEATING COULD ALLOW A FEW ISOLATED STORMS TO
FIRE ALONG THE FRONT SUNDAY LATE AFTERNOON...POSSIBLY AFFECTING
LOCATIONS NORTH OF A GREAT BEND-SALINA LINE. HOWEVER...GIVEN WEAK
FORCING AT PEAK HEATING...THINKING THE MORE PROBABLE SCENARIO IS
CLUSTER OF THUNDERSTORMS DEVELOPING OVER NORTHWEST KS/SOUTHWEST NE
AND PROPAGATING EAST/SOUTHEAST INTO CENTRAL KS AFTER DARK. GIVEN
NAM`S PLACEMENT OF FRONT...THINKING LOCATIONS NORTH OF GREAT
BEND-SALINA HAVE A DECENT CHANCE OF SEEING MOISTURE...ALONG WITH
POTENTIAL FOR A STRONG/SEVERE FORWARD PROPAGATING MCS CARRYING AN
ISOLATED DAMAGING WIND THREAT.
FRONT LIFTS NORTH FOR MON-TUE...EFFECTIVELY SHUTTING DOWN
PRECIPITATION CHANCES AND CONTINUING THE WINDY AND HOT WEATHER.
WINDS WILL LIKELY FLIRT WITH WIND ADVISORY CRITERIA ONCE AGAIN SUN
AND MON...AND POSSIBLY TUE AS WELL. FURTHERMORE...PER THE
GFS...CANNOT COMPLETELY RULE OUT A STRAY THUNDERSTORMS GETTING INTO
RUSSELL/BARTON COUNTIES TUE EVENING...BUT ONCE AGAIN SUSPECT BETTER
CHANCES WILL REMAIN WEST/NORTHWEST.
ADK
&&
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 306 PM CDT SAT JUN 22 2013
THE UPPER RIDGE IS PROGGED TO BUILD IN EARNEST ACROSS THE WESTERN
CONUS LATE NEXT WEEK. THE HIGHER AMPLITUDE FLOW REGIME WILL
EVENTUALLY ALLOW A SIGNIFICANT UPPER TROF TO DROP SOUTHEAST ACROSS
THE GREAT LAKES WHICH WILL DEVELOP INTO AN EASTERN CONUS LONGWAVE
BY NEXT WEEKEND. THE RESULT FOR KANSAS WILL BE A CONTINUATION OF
THE BREEZY AND HOT WEATHER THROUGH MID-WEEK WITH A COLD FRONTAL
PASSAGE AND SOMEWHAT COOLER OR LESS HOT CONDITIONS BY
FRIDAY/SATURDAY. LATEST PROGGED LOW LEVEL THICKNESS VALUES/THERMAL
FIELDS WOULD SUPPORT HOTTER MAXS AHEAD OF THE FRONTAL PASSAGE FOR
WEDNESDAY AND THURSDAY...WITH MAXS AT OR ABOVE THE CENTURY MARK
FOR LOCATIONS ALONG/WEST OF I-135. THE GFS LATEST FRONTAL TIMING
COULD ALLOW FOR A VERY HOT BUBBLE OF COMPRESSED AIR ON THE
WESTERLY COMPONENT FLOW ACROSS MUCH OF SOUTHERN KANSAS ON THURSDAY
AFTERNOON. SO FOR NOW HAVE MADE A SLIGHT UP-TWEAK TO THE LOADED
INITIALIZATION WHICH IS ALSO ABOVE GMOS VALUES. WILL CONTINUE TO
CARRY SLIGHT CHANCE POPS THURSDAY INTO EARLY FRIDAY...THOUGH
FORCING REMAINS RATHER WEAK AND LIKELY TIED TO FRONTAL CONVERGENCE
AND MAINLY DIURNALLY DRIVEN CONVECTION WITH CARRYOVER INTO
THURSDAY NIGHT EARLY FRIDAY MORNING.
DARMOFAL
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1213 PM CDT SAT JUN 22 2013
VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD. ONLY AVIATION
CONCERN WILL BE GUSTY WINDS THIS AFTERNOON AND INTO THE EVENING.
WINDS FROM A SOUTHERLY DIRECTION AT SPEEDS IN A 30 TO 35 MPH RANGE
CAN BE EXPECTED WITH GUSTS TO NEAR 40 MPH AT
RSL...GBD...HUT...SLN...ICT...AND AAO.
CHANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 75 96 74 95 / 10 10 10 10
HUTCHINSON 75 98 74 97 / 10 10 20 10
NEWTON 74 96 74 95 / 10 10 10 10
ELDORADO 74 93 74 93 / 0 0 10 10
WINFIELD-KWLD 75 94 74 94 / 0 0 10 10
RUSSELL 75 99 70 98 / 10 20 40 10
GREAT BEND 75 100 71 98 / 10 10 30 10
SALINA 75 98 72 97 / 10 10 40 10
MCPHERSON 75 98 74 96 / 10 10 20 10
COFFEYVILLE 75 92 74 92 / 10 0 10 10
CHANUTE 74 92 74 91 / 10 0 10 10
IOLA 74 92 74 91 / 10 0 10 10
PARSONS-KPPF 75 92 74 91 / 10 0 10 10
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 8 PM CDT THIS EVENING FOR KSZ032-033-047-048-
050-067-082-091.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS TOPEKA KS
1241 PM CDT SAT JUN 22 2013
.UPDATE...
ISSUED AT 1233 PM CDT SAT JUN 22 2013
UPDATED THE AFTERNOON GRIDS TO REMOVE THUNDER AND EVENTUALLY
END ALL PRECIP BY AROUND 19Z. TEMPERATURES...WINDS AND HEAT
INDICES NORTH CENTRAL ALTHOUGH DELAYED...STILL EXPECTED TO RECOVER
THROUGH THE MIDDLE AND LATE AFTERNOON HOURS. WILL LIKELY NEED
ANOTHER UPDATE IN THE NEXT ONE TO TWO HOURS TO REMOVE ALL MENTION
OF PRECIP.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 343 AM CDT SAT JUN 22 2013
LARGE COMPLEX OF RAIN AND THUNDERSTORMS CONTINUES TO MARCH EASTWARD
ACROSS MUCH OF NORTH AND EAST NEBRASKA AND POINTS NE. SOUTHERN
PROGRESS OF THE OUTFLOW HAS SLOWED SOMEWHAT THE PAST HOUR OR SO.
SHORTWAVE TROF NOTED IN WV IMAGERY OVER EASTERN KS ATTM...BUT IS
PRODUCING ONLY CLOUDS SO FAR AS IT PASSES. EVENING SOUNDING AT TOP
SHOWED STEEP LAPSE RATES IN THE 750 TO 550 MB LAYER...HOWEVER CAP IS
STRONG BELOW 700MB AND COLUMN IS DRY THROUGH ABOUT 400MB. ONLY
GUIDANCE THAT SUGGESTS PRECIP THIS MORNING HAS BEEN OUT WEST WITH
THE HRRR FOR SEVERAL RUNS...ALL OTHERS REMAIN DRY. WILL CARRY A
SILENT POP WEST OF MANHATTAN FOR A FEW HOURS THIS MORNING. COULD
GET A BRIEF BREAK NORTH FROM SOME OF THE OUTFLOW FROM THE
NORTH...BUT EXPECT THAT WOULD BE SHORT LIVED. HIGHS STILL EXPECTED
INTO THE LOWER TO MIDDLE 90S WITH HEAT INDICES RUNNING AROUND 100
ALONG THE KS RIVER VALLEY. WINDS BECOME QUITE BREEZY OUT OF THE
SOUTH AS YOU GO WESTWARD...WITH SUSTAINED AFTERNOON WINDS AROUND 30
WITH GUSTS 35-40 POSSIBLE. WILL MONITOR TRENDS FOR WIND ADVISORY
BUT IS BORDERLINE AT THIS TIME. OVERNIGHT LOWS EXPECTED ON THE WARM
SIDE AGAIN IN THE MIDDLE 70S. 67
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 343 AM CDT SAT JUN 22 2013
MID RANGE AND EXTENDED FORECAST (SUNDAY THROUGH FRIDAY)...
VERY LITTLE CHANGE IN THIS FORECAST PACKAGE AS MODELS ARE STILL
CONSISTENT IN SHOWING A LARGE SCALE RIDGING PATTERN ACROSS THE
SOUTHEASTERN PORTION OF THE CONUS THROUGH THE WEEKEND...WITH A
PACIFIC TROUGH OVER THE WEST COAST. LIGHT SOUTHWEST FLOW WILL BE
PRESENT OVER THE ROCKY MOUNTAINS UP THROUGH THE NORTHERN
PLAINS...WITH THE CENTRAL PLAINS BEING ON THE EASTERN FRINGE OF THE
BETTER FLOW. EXPECT WARM TEMPERATURES TO CONTINUE FOR SUNDAY...WITH
A PRETTY DECENT CHANCE FOR RAIN SUNDAY NIGHT AS A DISTURBANCE WITHIN
THE SOUTHWESTERLY FLOW ALOFT WILL TRIGGER A ROUND OF THUNDERSTORMS
ACROSS SOUTHERN NEBRASKA AND NORTHERN KANSAS. THE BEST CHANCE FOR
RAIN WILL BE ALONG THE KS/NE BORDER...WITH DECREASING CHANCES
FURTHER SOUTH ALONG INTERSTATE 70.
EXPECT LITTLE IN THE WAY OF CONVECTIVE CHANCES AFTER THE SUNDAY
NIGHT ROUND OF THUNDERSTORMS. ECMWF HAS BEEN CONSISTENT IN
PREDICTING THE FOUR CORNERS MID LEVEL RIDGE TO SET UP BY MID
WEEK...WHICH WILL KEEP TEMPERATURES IN THE AREA WARM THROUGH THE
EXTENDED PERIOD. TEMPERATURES GENERALLY WILL REMAIN IN THE LOWER TO
MID 90S ACROSS EASTERN KANSAS THROUGH THE EXTENDED PERIOD...WITH
TEMPS REACHING THE MID TO UPPER 90S IN WESTERN KANSAS. THE NEXT
CHANCES FOR RAIN WILL BE RATHER MINIMAL AS A BOUNDARY LOOKS TO SLIDE
INTO THE AREA IN THE THURSDAY/FRIDAY TIME FRAME. THIS BOUNDARY WOULD
BE THE FOCUS FOR ANY POTENTIAL CONVECTION DURING THAT TIME PERIOD.
MADE VIRTUALLY NO CHANGE TO THE FORECAST FOR THE LATE PART OF THE
WEEK FOR THESE POTENTIAL SHOWERS.
JL
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1233 PM CDT SAT JUN 22 2013
VFR CONDITIONS WILL PERSIST THROUGH THE PERIOD AS THIS AFTERNOONS
CONVECTION/SHOWERS TO THE WEST OF THE TERMINALS DISSIPATES AND TONIGHTS
CONVECTION REMAINS NORTH AND WEST OF THE TERMINALS AS WELL THROUGH
THE PERIOD. GUSTY SOUTH WINDS THIS AFTERNOON WILL DECREASE TO
11-14KTS AFT 02Z...BEFORE INCREASING AGAIN AFT 14Z.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...63
SHORT TERM...CRAVEN
LONG TERM...LEIGHTON
AVIATION...63
AREA FORECAST DISCUSSION
NWS TOPEKA KS
618 AM CDT SAT JUN 22 2013
UPDATED FOR AVIATION.
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 343 AM CDT SAT JUN 22 2013
LARGE COMPLEX OF RAIN AND THUNDERSTORMS CONTINUES TO MARCH EASTWARD
ACROSS MUCH OF NORTH AND EAST NEBRASKA AND POINTS NE. SOUTHERN
PROGRESS OF THE OUTFLOW HAS SLOWED SOMEWHAT THE PAST HOUR OR SO.
SHORTWAVE TROF NOTED IN WV IMAGERY OVER EASTERN KS ATTM...BUT IS
PRODUCING ONLY CLOUDS SO FAR AS IT PASSES. EVENING SOUNDING AT TOP
SHOWED STEEP LAPSE RATES IN THE 750 TO 550 MB LAYER...HOWEVER CAP IS
STRONG BELOW 700MB AND COLUMN IS DRY THROUGH ABOUT 400MB. ONLY
GUIDANCE THAT SUGGESTS PRECIP THIS MORNING HAS BEEN OUT WEST WITH
THE HRRR FOR SEVERAL RUNS...ALL OTHERS REMAIN DRY. WILL CARRY A
SILENT POP WEST OF MANHATTAN FOR A FEW HOURS THIS MORNING. COULD
GET A BRIEF BREAK NORTH FROM SOME OF THE OUTFLOW FROM THE
NORTH...BUT EXPECT THAT WOULD BE SHORT LIVED. HIGHS STILL EXPECTED
INTO THE LOWER TO MIDDLE 90S WITH HEAT INDICES RUNNING AROUND 100
ALONG THE KS RIVER VALLEY. WINDS BECOME QUITE BREEZY OUT OF THE
SOUTH AS YOU GO WESTWARD...WITH SUSTAINED AFTERNOON WINDS AROUND 30
WITH GUSTS 35-40 POSSIBLE. WILL MONITOR TRENDS FOR WIND ADVISORY
BUT IS BORDERLINE AT THIS TIME. OVERNIGHT LOWS EXPECTED ON THE WARM
SIDE AGAIN IN THE MIDDLE 70S. 67
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 343 AM CDT SAT JUN 22 2013
MID RANGE AND EXTENDED FORECAST (SUNDAY THROUGH FRIDAY)...
VERY LITTLE CHANGE IN THIS FORECAST PACKAGE AS MODELS ARE STILL
CONSISTENT IN SHOWING A LARGE SCALE RIDGING PATTERN ACROSS THE
SOUTHEASTERN PORTION OF THE CONUS THROUGH THE WEEKEND...WITH A
PACIFIC TROUGH OVER THE WEST COAST. LIGHT SOUTHWEST FLOW WILL BE
PRESENT OVER THE ROCKY MOUNTAINS UP THROUGH THE NORTHERN
PLAINS...WITH THE CENTRAL PLAINS BEING ON THE EASTERN FRINGE OF THE
BETTER FLOW. EXPECT WARM TEMPERATURES TO CONTINUE FOR SUNDAY...WITH
A PRETTY DECENT CHANCE FOR RAIN SUNDAY NIGHT AS A DISTURBANCE WITHIN
THE SOUTHWESTERLY FLOW ALOFT WILL TRIGGER A ROUND OF THUNDERSTORMS
ACROSS SOUTHERN NEBRASKA AND NORTHERN KANSAS. THE BEST CHANCE FOR
RAIN WILL BE ALONG THE KS/NE BORDER...WITH DECREASING CHANCES
FURTHER SOUTH ALONG INTERSTATE 70.
EXPECT LITTLE IN THE WAY OF CONVECTIVE CHANCES AFTER THE SUNDAY
NIGHT ROUND OF THUNDERSTORMS. ECMWF HAS BEEN CONSISTENT IN
PREDICTING THE FOUR CORNERS MID LEVEL RIDGE TO SET UP BY MID
WEEK...WHICH WILL KEEP TEMPERATURES IN THE AREA WARM THROUGH THE
EXTENDED PERIOD. TEMPERATURES GENERALLY WILL REMAIN IN THE LOWER TO
MID 90S ACROSS EASTERN KANSAS THROUGH THE EXTENDED PERIOD...WITH
TEMPS REACHING THE MID TO UPPER 90S IN WESTERN KANSAS. THE NEXT
CHANCES FOR RAIN WILL BE RATHER MINIMAL AS A BOUNDARY LOOKS TO SLIDE
INTO THE AREA IN THE THURSDAY/FRIDAY TIME FRAME. THIS BOUNDARY WOULD
BE THE FOCUS FOR ANY POTENTIAL CONVECTION DURING THAT TIME PERIOD.
MADE VIRTUALLY NO CHANGE TO THE FORECAST FOR THE LATE PART OF THE
WEEK FOR THESE POTENTIAL SHOWERS.
JL
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 616 AM CDT SAT JUN 22 2013
VFR CONDITIONS EXPECTED FOR THE PERIOD. SOUTHERLY WINDS INCREASE
THROUGHOUT THE DAY. CLOUDS GENERALLY AOA 15KFT...WITH NEXT CHANCE
FOR THUNDERSTORMS TOWARD THE NEBRASKA BORDER LATE IN THE PERIOD. 67
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CRAVEN
LONG TERM...LEIGHTON
AVIATION...67
AREA FORECAST DISCUSSION
NWS TOPEKA KS
355 AM CDT SAT JUN 22 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 343 AM CDT SAT JUN 22 2013
LARGE COMPLEX OF RAIN AND THUNDERSTORMS CONTINUES TO MARCH EASTWARD
ACROSS MUCH OF NORTH AND EAST NEBRASKA AND POINTS NE. SOUTHERN
PROGRESS OF THE OUTFLOW HAS SLOWED SOMEWHAT THE PAST HOUR OR SO.
SHORTWAVE TROF NOTED IN WV IMAGERY OVER EASTERN KS ATTM...BUT IS
PRODUCING ONLY CLOUDS SO FAR AS IT PASSES. EVENING SOUNDING AT TOP
SHOWED STEEP LAPSE RATES IN THE 750 TO 550 MB LAYER...HOWEVER CAP IS
STRONG BELOW 700MB AND COLUMN IS DRY THROUGH ABOUT 400MB. ONLY
GUIDANCE THAT SUGGESTS PRECIP THIS MORNING HAS BEEN OUT WEST WITH
THE HRRR FOR SEVERAL RUNS...ALL OTHERS REMAIN DRY. WILL CARRY A
SILENT POP WEST OF MANHATTAN FOR A FEW HOURS THIS MORNING. COULD
GET A BRIEF BREAK NORTH FROM SOME OF THE OUTFLOW FROM THE
NORTH...BUT EXPECT THAT WOULD BE SHORT LIVED. HIGHS STILL EXPECTED
INTO THE LOWER TO MIDDLE 90S WITH HEAT INDICES RUNNING AROUND 100
ALONG THE KS RIVER VALLEY. WINDS BECOME QUITE BREEZY OUT OF THE
SOUTH AS YOU GO WESTWARD...WITH SUSTAINED AFTERNOON WINDS AROUND 30
WITH GUSTS 35-40 POSSIBLE. WILL MONITOR TRENDS FOR WIND ADVISORY
BUT IS BORDERLINE AT THIS TIME. OVERNIGHT LOWS EXPECTED ON THE WARM
SIDE AGAIN IN THE MIDDLE 70S. 67
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 343 AM CDT SAT JUN 22 2013
MID RANGE AND EXTENDED FORECAST (SUNDAY THROUGH FRIDAY)...
VERY LITTLE CHANGE IN THIS FORECAST PACKAGE AS MODELS ARE STILL
CONSISTENT IN SHOWING A LARGE SCALE RIDGING PATTERN ACROSS THE
SOUTHEASTERN PORTION OF THE CONUS THROUGH THE WEEKEND...WITH A
PACIFIC TROUGH OVER THE WEST COAST. LIGHT SOUTHWEST FLOW WILL BE
PRESENT OVER THE ROCKY MOUNTAINS UP THROUGH THE NORTHERN
PLAINS...WITH THE CENTRAL PLAINS BEING ON THE EASTERN FRINGE OF THE
BETTER FLOW. EXPECT WARM TEMPERATURES TO CONTINUE FOR SUNDAY...WITH
A PRETTY DECENT CHANCE FOR RAIN SUNDAY NIGHT AS A DISTURBANCE WITHIN
THE SOUTHWESTERLY FLOW ALOFT WILL TRIGGER A ROUND OF THUNDERSTORMS
ACROSS SOUTHERN NEBRASKA AND NORTHERN KANSAS. THE BEST CHANCE FOR
RAIN WILL BE ALONG THE KS/NE BORDER...WITH DECREASING CHANCES
FURTHER SOUTH ALONG INTERSTATE 70.
EXPECT LITTLE IN THE WAY OF CONVECTIVE CHANCES AFTER THE SUNDAY
NIGHT ROUND OF THUNDERSTORMS. ECMWF HAS BEEN CONSISTENT IN
PREDICTING THE FOUR CORNERS MID LEVEL RIDGE TO SET UP BY MID
WEEK...WHICH WILL KEEP TEMPERATURES IN THE AREA WARM THROUGH THE
EXTENDED PERIOD. TEMPERATURES GENERALLY WILL REMAIN IN THE LOWER TO
MID 90S ACROSS EASTERN KANSAS THROUGH THE EXTENDED PERIOD...WITH
TEMPS REACHING THE MID TO UPPER 90S IN WESTERN KANSAS. THE NEXT
CHANCES FOR RAIN WILL BE RATHER MINIMAL AS A BOUNDARY LOOKS TO SLIDE
INTO THE AREA IN THE THURSDAY/FRIDAY TIME FRAME. THIS BOUNDARY WOULD
BE THE FOCUS FOR ANY POTENTIAL CONVECTION DURING THAT TIME PERIOD.
MADE VIRTUALLY NO CHANGE TO THE FORECAST FOR THE LATE PART OF THE
WEEK FOR THESE POTENTIAL SHOWERS.
JL
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1128 PM CDT FRI JUN 21 2013
VFR CONDITIONS AS SCT TO BKN CIRRUS CLOUDS SKIRT ACROSS
KTOP/KFOE/KMHK. EXPECT GRADIENT TO RELAX SLIGHTLY WITH OVERNIGHT
SOUTH WINDS AROUND 10 KTS AT KTOP/KFOE. KMHK SHOULD STAY UP NEAR 12
KTS. WIND DIRECTION BACKS SLIGHTLY TO THE SOUTH AT SITES...INCREASING
BETWEEN 15-20 KTS WITH GUSTS 25-30 KTS AFT 14Z.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CRAVEN
LONG TERM...LEIGHTON
AVIATION...BOWEN
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1154 PM MDT FRI JUN 21 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 216 PM MDT FRI JUN 21 2013
AS OF 3 PM CDT...2 PM MDT...SKIES ACROSS THE TRI-STATE WERE CLEAR
ALBEIT A LITTLE HAZY FROM SMOKE THAT CONTINUES TO STREAM IN FROM
FIRES IN SOUTH CENTRAL COLORADO. SOME CUMULUS AND TOWERING CUMULUS
COULD BE SEEN ON VISIBLE SATELLITE IMAGERY JUST NORTH OF
AKRON...COLORADO. SOUTH WINDS HAVE PICKED UP MAINLY EAST OF A LINE
FROM TRENTON...NEBRASKA TO COLBY AND LEOTI KANSAS AS A SURFACE LOW
PRESSURE SYSTEM DEEPENS TO THE WEST. TEMPERATURES RANGED FROM THE LOW
90S IN EAST COLORADO TO NEAR 100 ACROSS SOME PARTS OF KANSAS AND
SOUTHWEST NEBRASKA. VERY DRY AIR WAS ALSO STARTING TO MOVE IN FROM
THE SOUTHWEST.
SIMILAR TO YESTERDAY...ISOLATED THUNDERSTORMS ARE EXPECTED TO
DEVELOP ALONG A DRYLINE. SURFACE CONVERGENCE IS BEGINNING TO APPEAR
IN THE SURFACE WIND FIELD ALONG THE DRYLINE WHICH WILL BE THE FOCUS
OF STORM DEVELOPMENT. THE HRRR AND NAM MODELS SUGGEST STORM
INITIATION WILL OCCUR IN FAR WESTERN KANSAS. STORMS SHOULD BE
CONFINED MAINLY ALONG AND EAST OF A LINE FROM YUMA COLORADO TO
GOODLAND KANSAS TO TRIBUNE KANSAS AND WEST OF A LINE FROM MCCOOK
NEBRASKA TO RUSSELL SPRINGS KANSAS. ANY STORM THAT IS ABLE TO
DEVELOP WILL BE STRONG TO SEVERE WITH LARGE HAIL AND DAMAGING WINDS
AS THE MAIN THREATS.
FOR TONIGHT...GUSTY WINDS WILL CONTINUE A LOW LEVEL JET DEVELOPS
OVER THE EASTERN HALF. WINDS SHOULD BE BELOW WIND ADVISORY CRITERIA
WITH THE STRONGEST WINDS REMAINING TO THE SOUTH OVER SOUTHWEST AND
SOUTH CENTRAL KANSAS. LOWS WILL STRUGGLE TO FALL TONIGHT WITH THE
ATMOSPHERE IN A MIXED STATE SO HAVE GONE ABOVE GUIDANCE FOR LOWS.
TONIGHTS TEMPERATURE FORECAST IS VERY SIMILAR TO WHAT ACTUALLY
OCCURRED LAST NIGHT.
FOR TOMORROW...A REPEAT OF TODAY IS EXPECTED FOR THE MOST PART.
TEMPERATURES ARE NOT EXPECTED TO BE AS HOT AS TODAY WITH HIGHS ONLY
REACHING THE MID TO UPPER 90S WITH A FEW SPOTS REACHING 100. A WEAK
FRONT WILL MOVE INTO THE AREA FROM THE NORTH...RESULTING IN MAINLY A
WIND SHIFT WITH EVER SO SLIGHTLY COOLER TEMPERATURES. WITH A DRYLINE
STILL IN PLACE...ISOLATED THUNDERSTORMS ARE POSSIBLE AGAIN FOR
TOMORROW. ANY STORMS THAT ARE ABLE TO DEVELOP WOULD LIKELY BECOME
SEVERE. THERE IS A SLIGHT RISK FOR SEVERE WEATHER ACROSS SOUTHWEST
NEBRASKA TOMORROW AND THAT SEEMS REASONABLE GIVEN THE LOCATION OF
THE FRONT TOMORROW. THE FRONT SHOULD PROVIDE A BETTER FOCUS FOR
THUNDERSTORM DEVELOPMENT OVER THE NORTHERN THIRD OF THE FORECAST
AREA. GUSTY SOUTH WINDS ARE EXPECTED AGAIN WITH A LOW PRESSURE
DEEPENING TO THE WEST.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 215 PM MDT FRI JUN 21 2013
A SIGNIFICANT CHANGE IN THE UPPER PATTERN WILL TAKE PLACE DURING
THIS EXTENDED PERIOD. THE CURRENT SOUTHWEST FLOW ALOFT
ACCOMPANIED BY NUMEROUS MINOR DISTURBANCES WILL TRANSITION TO A
BUILDING UPPER RIDGE...STARTING OVER NM/AZ TUESDAY AND ULTIMATELY
ENCOMPASSING ALL OF THE CENTRAL ROCKIES BY THE END OF THE WEEK.
THERE STILL LOOKS TO BE A COUPLE OF OPPORTUNITIES FOR STORMS
COMING OUT OF COLORADO AND MOVING ACROSS THE CWA SATURDAY AND
SUNDAY EVENING AS WEAK SHORT WAVE TROUGHS MOVE THROUGH THE FLOW.
AFTER THAT...PRECIP POTENTIAL WILL DIMINISH AS THE UPPER RIDGE AND
WARMING MID-LEVEL TEMPS BEGIN TO DOMINATE.
TEMPERATURES ARE EXPECTED TO REMAIN WELL ABOVE NORMAL DURING THE
PERIOD WITH HIGHS MOSTLY IN THE MIDDLE 90S TO NEAR 100 AND LOWS IN
THE 60S TO NEAR 70.
CURRENT EXTENDED GUIDANCE BEYOND THIS PERIOD SUGGESTS THE UPPER
RIDGE WILL CONTINUE TO BUILD NORTH TOWARD IDAHO BY NEXT WEEKEND.
IF THAT PANS OUT...THE UPPER FLOW WILL BECOME NORTHWEST OVER THE
CWA POSSIBLY INCREASING THE CHANCE FOR LATE DAY STORMS MOVING
SOUTHEAST OFF THE CHEYENNE RIDGE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1148 PM MDT FRI JUN 21 2013
CONDITIONS AT MCK AND GLD WILL CONTINUE TO BE VFR THROUGH THE TAF
PERIOD. OUTFLOW FROM THUNDERSTORMS OVER CENTRAL SOUTHERN NEBRASKA
REINFORCING THE COLDFRONTAL BOUNDARY WILL CONTINUE TO AFFECT THE
WINDS AT MCK...KEEPING THEM GENERALLY LIGHT OUT OF THE NORTHEAST
TO EAST OVERNIGHT. WINDS AT MCK WILL TURN SOUTH AND BECOME GUSTY
DURING THE AFTERNOON AS THE FRONT MOVES NORTHWARD. GUSTY SOUTH WINDS
AT GLD WILL SLACKEN SOMEWHAT TOWARDS SUNRISE...BUT WILL RETURN BY
AFTERNOON. THERE IS A POSSIBILITY OF ISOLATED THUNDERSTORMS
DEVELOPING ACROSS THE CENTRAL HIGH PLAINS REGION DURING THE
AFTERNOON AND EVENING...BUT THE CHANCE OF ANY STORM MOVING OVER
EITHER TAF SITE IS SLIM ENOUGH THAT ANY MENTION OF STORMS HAS BEEN
LEFT OUT.
&&
.FIRE WEATHER...
ISSUED AT 216 PM MDT FRI JUN 21 2013
CRITICAL FIRE WEATHER CONDITIONS ARE DEVELOPING TO THE
SOUTHWEST...MAINLY OVER GREELEY AND WALLACE COUNTIES KANSAS AND
CHEYENNE AND KIT CARSON COUNTIES IN COLORADO. EVEN THOUGH RED FLAG
CRITERIA WILL BE MET FOR THESE LOCATIONS TODAY FOR WIND AND RELATIVE
HUMIDITY...RECENT RAINFALL AND HIGHER FUEL MOISTURE CONTENT ARE
PREVENTING EXPLOSIVE FIRE WEATHER CONDITIONS FROM BECOMING A
PROBLEM. THEREFORE...HAVE OPTED NOT TO ISSUE A RED FLAG WARNING.
THE SAME STORY WILL REPEAT ITSELF AGAIN TOMORROW WITH LOW RELATIVE
HUMIDITIES FILTERING IN FROM THE SOUTHWEST AND WINDS INCREASING
BEHIND THE DRYLINE IN THE AFTERNOON. FUELS COULD BE MORE RIPE FOR
FIRE POTENTIAL TOMORROW AFTER A COUPLE HOT DAYS WITH LITTLE RAINFALL
BUT THINKING THAT FUEL MOISTURE WILL STILL BE HIGH ENOUGH THAT A RED
FLAG WARNING WILL NOT BE WARRANTED.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...RRH
LONG TERM...DLF
AVIATION...LOCKHART
FIRE WEATHER...RRH
AREA FORECAST DISCUSSION
NWS JACKSON KY
120 AM EDT SAT JUN 22 2013
.UPDATE...
ISSUED AT 120 AM EDT SAT JUN 22 2013
CLUSTER OF SHOWERS/STORMS WHICH DROPPED SOME SMALL HAIL IN THE TRI-
CITIES AREA OF NORTHEAST TENNESSEE EARLIER CONTINUES TO PINWHEEL
WESTWARD. THESE SHOWERS/STORMS APPEAR DESTINED TO VISIT HARLAN AND
BELL COUNTIES IN SOME SHAPE OR FORM AND WILL HOLD ONTO A 20 POP
THROUGH THE REST OF THE NIGHT FOR THOSE AREAS. OTHERWISE...SHOWERS IN
THE BLUEGRASS HAVE DIED OUT SO REMOVED ANY MENTION OF RAIN THERE.
REST OF THE FORECAST IS ON TRACK...
UPDATE ISSUED AT 900 PM EDT FRI JUN 21 2013
THUNDERSTORMS HAVE DIED DOWN IN OUR FORECAST AREA...BUT ISOLATED
STORMS CONTINUE TO FIRE AROUND US. INHERITED FORECAST DROPPED ALL
MENTION OF POPS AFTER 00Z EXCEPT DOWN SOUTH ALONG THE TN AND VA
BORDERS AND KEPT WITH THIS THINKING. WILL NEED TO MONITOR THE STORMS
FIRING OVER THE BLUEGRASS THOUGH TO MAKE SURE ADDITIONAL ACTIVITY
DOESN/T FIRE ON OUTFLOWS INTO OUR BLUEGRASS COUNTIES. OTHERWISE...
SHOULD BE A QUIET NIGHT WITH REPEAT VALLEY FOG DEVELOPMENT. FORECAST
LOWS IN THE LOW TO MID 60S LOOK GOOD.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 314 PM EDT FRI JUN 21 2013
BEEN WATCHING THE MCS ENTERING NORTHERN ILL TO SEE HOW FAR SOUTH IT
WILL KEEP GOING AND WHERE THE OUTFLOW BOUNDARIES END UP. CURRENT
THINKING IS THAT IF IT DOES NOT FALL APART BEFORE IT REACHES THE
AREA...IT SHOULD STAY WEST OF THE AREA. THE HRRR IS SHOWING ISOLATED
TO SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING DURING THE
AFTERNOON AND EVENING HOURS. THE INSTABILITY IS THERE TO SUPPORT
THUNDERSTORM DEVELOPMENT. ONE CONCERN IS THE DRY AIR IN THE MID
LAYERS WHICH COULD HELP TO PRODUCE SOME STRONG OUTFLOW WINDS. THE
OTHER CONCERN IS THAT THE WINDS ALOFT ARE SO LIGHT...THE STORMS WILL
BE MOVING VERY SLOWLY. THIS MAY ALLOW A LOT OF PRECIPITATION TO FALL
OVER A SMALL AREA AND COULD RESULT IN DITCHES AND LOW WATER
CROSSINGS TO RUN FULL. THERE HAS ALREADY BEEN ONE STRONG STORM
DEVELOP OVER LESLIE COUNTY THIS AFTERNOON. NO REPORTS OF ANY DAMAGE
OR FLOODING WERE RECEIVED. A REPEAT OF THIS DIURNALLY BASED PULSE
THUNDERSTORM ACTIVITY IS ANTICIPATED ON SATURDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 314 PM EDT FRI JUN 21 2013
FAIRLY BUSY PATTERN FOR THE OFFICIAL START OF SUMMER. OVERALL
MODELS ARE IN GOOD AGREEMENT THROUGH THE EXTENDED. IN FAIRLY HIGH
AMPLITUDE FLOW...CORE WESTERLIES REMAINS NORTH OF OUR AREA UNTIL THE
END OF THE FORECAST WINDOW. EASTERN CONUS RIDGING ALOFT RETREATS
WESTWARD WITH TIME THROUGH THE PERIOD. EMBEDDED WITHIN THIS RIDGE
EARLY ON IS AN AREA OF TROUGH-I-NE SS OR A CENTER OF RELATIVE LOWER
HEIGHTS. THIS LOCALIZED AREA OF LOWER HEIGHTS WILL OPEN UP AND DRIFT
NORTHEAST THROUGH THE LATTER PART OF THE WEEKEND AND EARLY NEXT
WEEK...SPREADING ITS LIMITED INFLUENCE THROUGH THE SOUTHERN
APPALACHIANS. FOR SUCH A WEAK FEATURE...CONSISTENT WITH THIS TIME OF
YEAR...THE MODELS DO RATHER WELL IN DEPICTING SIMILAR EVOLUTIONS...
THOUGH THE ECMWF MAINTAINS THE DISTINCT UPPER LOW LONGER THAN THE
GFS. THIS RIDGING ACROSS THE REGION IS SUPPRESSED SOUTHWARD AS THIS
AREA OF LOWER HEIGHTS GRADUALLY LIFTS NORTHWARD ACROSS EASTERN
KENTUCKY SUNDAY. THEREAFTER THE RIDGE SHIFTS WESTWARD AND THE
PATTERN AMPLIFIES...RESULTING IN ENERGY ALONG THE NORTHERN TIER
SETTLING SOUTHWARD ALONG THE EASTERN SIDE OF THE RIDGE...EFFECTIVELY
CARVING OUT A TROUGH OVER THE EASTERN CONUS TO FINISH OUT THE WEEK.
SENSIBLE WEATHER WILL BE DOMINATED BY THE DIURNAL CYCLE THROUGH THE
BULK OF THE EXTENDED AS SFC HIGH PRESSURE OVER THE AREA WILL BE TOO
WEAK TO SUPPRESS ALL CONVECTION ONCE DAYTIME HEATING KICKS IN. THERE
IS REALLY NO FEATURE TO KEY IN ON FOR MORE ORGANIZED...WIDESPREAD
ACTIVITY THROUGH THE START OF THE UPCOMING WORK WEEK. THAT CHANGES
TOWARDS WEEKS END AS A STORM SYSTEM DROPPING SOUTHWARD OUT OF CANADA
HELPS TO GENERATE A BETTER CHANCE FOR RAIN ACROSS OUR AREA...THOUGH
TIMING AND SPECIFICS REMAIN IN DOUBT. WARM AND SEASONABLE WEATHER IS
THUS ON TAP FOR THE REST OF THE WEEKEND AND THROUGH THE START OF THE
NEW WORK WEEK. DURING THE FIRST FEW DAYS OF THE EXTENDED...OUR BEST
OPPORTUNITY FOR SOME GARDEN VARIETY...HIT AND MISS THUNDERSTORMS
APPEARS TO BE SUNDAY AS HEIGHTS DROP SLIGHTLY DUE TO THE PASSING
FEATURE...DISTURBANCE FROM THE SOUTH. ADDITIONAL CLOUD COVER...AND A
BETTER POTENTIAL OF CONVECTION AFTER MID WEEK ON SHOULD HELP TEMPER
THE WARMTH A BIT.
FOR TEMPS GENERALLY STAYED CLOSE TO A BLEND OF MODEL GUIDANCE WHILE
MAINTAINING EFFECTS OF RELATIVE ELEVATION AL DIFFERENCES...WHERE
APPLICABLE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 120 AM EDT SAT JUN 22 2013
SURFACE HIGH PRESSURE WILL PROVIDE FOR MAINLY VFR CONDITIONS AND
LIGHT WINDS ACROSS THE AREA THROUGH THE PERIOD. PATCHY VALLEY FOG
WILL CONTINUE TO DEVELOP THROUGH DAWN...WITH SOME VSBY REDUCTIONS
EXPECTED AT LOZ AND SME. ISOLATED THUNDERSTORMS WILL THEN REFIRE
AFTER ABOUT 17Z TOMORROW...ALTHOUGH THE PROBABILITY THAT ONE WILL
IMPACT A TAF SITE IS ONLY AROUND 20 PERCENT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ABE
SHORT TERM...JJ
LONG TERM...GREIF/RAY
AVIATION...ABE
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
710 PM EDT SUN JUN 23 2013
.SYNOPSIS...
WARM AND MOIST AIR CONTINUES TO POOL SOUTH OF A STATIONARY FRONT
TO OUR NORTH. SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED
EACH DAY THROUGH THE WEEK AS SEVERAL DISTURBANCES CROSS THE
REGION. A LARGE UPPER LEVEL TROUGH WILL APPROACH FROM THE WEST
LATE IN THE WEEK. THIS WILL ALLOW FOR COOLER TEMPERATURES...BUT
INCREASE THE CHANCE FOR SHOWERS ACROSS THE REGION.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
.UPDATE...
HAVE CANCELLED THE SEVERE THUNDERSTORM WATCH FOR COOS...OXFORD...
ANDROSCOGGIN...AND GRAFTON COUNTIES. LARGE AREA OF CIN HAS
DEVELOPED OVER THESE AREAS IN THE WAKE OF A COLD POOL. ANY
THUNDERSTORMS THAT DO DEVELOP OVER THESE AREAS MAY STILL HAVE
HEAVY RAIN...SMALL HAIL...AND GUSTY WINDS...BUT SHOULD STAY NON
SEVERE. THE WATCH CONTINUES FOR SOUTHERN NH AND SW MAINE AS WELL
AS ADJACENT COASTAL AREAS.
SO FAR REPORTS OF SEVERE WEATHER HAVE BEEN SPOTTY WITH A FEW
REPORTS OF WIND DAMAGE AND LARGE HAIL RECEIVED. TEMPERATURES AND
DEW POINTS ARE DROPPING BEHIND THE COLD POOL AND THESE ELEMENTS
HAVE BEEN ADJUSTED IN THE LATEST FORECAST UPDATE.
&&
PREVIOUS DISCUSSION...
MESOSCALE MODELS LIKE THE HRRR HAVE A GOOD HANDLE ON ONGOING
CONVECTION TO OUR WEST. SHOWERS AND THUNDERSTORMS WHICH HAVE
FORMED IN THE HIGHER TERRAIN WILL COALESCE AND SPREAD DOWNSTREAM
IN THE NEXT FEW HOURS AS A COLD POOL DEVELOPS. SHOWERS AND
THUNDERSTORMS SHOULD FORM A LOOSE MULTICELL LINE OVER
CENTRAL/SOUTHERN NEW HAMPSHIRE AND INTO SW MAINE...MOVING OFFSHORE
THIS EVENING. THE SEVERE WEATHER THREAT LOOKS HIGHEST OVER
SOUTHERN AND CENTRAL NEW HAMPSHIRE WHERE MORE INSOLATION HAS
OCCURRED AND SURFACE-BASED CAPES OF 1200-1500 J/KG RESIDE.
THE BIGGEST SEVERE WEATHER THREAT WILL BE DAMAGING WINDS.
TRAINING...AMPLE UNIDIRECTIONAL SHEAR...AND PRECIPITATION LOADING
WILL SUPPORT THE THREAT OF WET DOWN BURSTS. FACTORS LIMITING SEVERE
WEATHER INCLUDE THE LACK OF ANY REAL FOCUSING MECHANISM OR UPPER
LEVEL SUPPORT...AS WELL AS A RELATIVELY HIGH FREEZING LEVEL.
NEW STORMS WILL LIKELY DEVELOP ALONG OUTFLOW MERGERS AND IN AREAS
OF DIFFERENTIAL HEATING.
GYX SOUNDING FROM THIS MORNING HAS 1.72 INCHES OF PRECIPITABLE
WATER...WHICH IS CLOSE TO 2 STANDARD DEVIATIONS ABOVE NORMAL FOR
THE END OF JUNE. SATURATED AND WARM CLOUDS WILL CONTINUE TO SUPPORT
VERY HEAVY RAIN AND WARM RAIN PROCESSES. QPF AMOUNTS FOR THIS
EVENING WILL VARY WIDELY DEPENDING ON WHERE CONVECTION DEVELOPS.
TRAINING CELLS AND ANY UPSLOPE COMPONENT WILL HELP TO LOCALLY
BOOST RAINFALL TOTALS OVER ISOLATED AREAS...PERHAPS 1-2 INCHES.
OTHER LOCATIONS MAY SEE LESS THAN A TENTH OF AN INCH.
MUCH OF THE ACTIVITY WILL DIMINISH WITH THE LOSS OF DIURNAL
HEATING...AND AS A WEAK SURFACE TROUGH SHIFTS OFFSHORE. OVERNIGHT
LOWS WILL BE IN THE LOWER TO MID 60S AS THE LOWER LEVELS OF THE
ATMOSPHERE REMAIN SATURATED...LEADING TO PATCHY DENSE FOG
DEVELOPMENT.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
ANOTHER WEAK TROUGH CROSSES THE AREA TOMORROW WITH NEARLY ZONAL
FLOW ALOFT. SKIES WILL BE PARTLY CLOUDY ACROSS THE SOUTH
INITIALLY...AND THIS ALONG WITH WESTERLY WINDS WILL HELP BOOST
TEMPERATURES INTO THE 80S AND 90S. DEW POINTS REMAIN IN THE UPPER
60S MAKING FOR AN UNPLEASANTLY MUGGY DAY. HEAT INDEX VALUES REACH
THE LOWER 90S...STAYING SHORT OF ADVISORY CRITERIA. MOISTURE
WILL BE WRUNG OUT ONCE AGAIN IN THE FORM OF AFTERNOON AND EVENING
THUNDERSTORMS. HIGHER INSTABILITY WILL BE LOCATED OVER NORTHERN
AREAS...BUT A THUNDERSTORM COULD POP UP ANYWHERE WITH BROAD WEAK
FORCING.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
WARM AND HUMID WEATHER WILL CONTINUE THROUGH TUESDAY AND INTO
WEDNESDAY. WARM 850 MB TEMPERATURES OF +18C COULD LEAD TO HIGHS
REACHING THE 90 DEGREE MARK ACROSS SOUTHERN AND EASTERN NEW
HAMPSHIRE AND SOUTHWEST MAINE. WITH DEW POINTS IN THE UPPER 60S TO
LOW 70S... IT WILL BE HUMID. HEAT INDEX READINGS WILL TOP 90
DEGREES ACROSS THE COASTAL PLAIN OF MAINE AND NEW HAMPSHIRE...
WITH SOME READINGS APPROACHING 95. ALTHOUGH THIS IS SHORT OF
ADVISORY LEVELS... IT WILL STILL BE NOTICEABLY HOT AND HUMID.
WITH HOT AND HUMID WEATHER COMES THE THREAT OF THUNDERSTORMS. A
SHORTWAVE TROUGH WILL BE CROSSING SOUTHERN CANADA AND INTO
NORTHERN NEW ENGLAND ON TUESDAY... ADDING UPPER LEVEL SUPPORT TO
AN UNSTABLE AIR MASS TO PRODUCE THUNDERSTORMS ACROSS THE REGION.
NAM IS SHOWING STRONGER MID AND UPPER LEVEL FLOW THAN THE GFS...
AND IF THIS IS THE CASE THEN THERE WILL BE AMPLE DEEP LAYER SHEAR
TO SUPPORT SUPERCELLS AND MULTICELL CLUSTERS AS DESCRIBED BY THE
STORM PREDICTION CENTER IN THEIR MORNING OUTLOOK INDICATING A
SLIGHT RISK ACROSS NORTHERN NEW ENGLAND. THE UNIDIRECTIONAL SHEAR
INDICATES THAT THERE WILL BE PRIMARILY A DAMAGING WINDS AND HAIL
THREAT RATHER THAN A TORNADO THREAT. IN ADDITION... THE HUMID AIR
WILL ALLOW THUNDERSTORMS TO DROP VERY HEAVY RAINFALL. ANY TRAINING
THUNDERSTORMS COULD LEAD TO FLASH FLOODING.
WITH HIGH DEW POINTS EXPECTED... DO NOT EXPECT TEMPERATURES TO COOL
OFF MUCH TUESDAY NIGHT. AFTER HIGHS IN THE 90S AND DEW POINTS IN
THE UPPER 60S TO LOW 70S... IT WILL BE DIFFICULT FOR TEMPERATURES
TO FALL MUCH BELOW 70 FOR MOST AREAS IN THE FEW HOURS OF NIGHT
THAT EXIST THIS TIME OF YEAR. AS A RESULT... RAISED LOW
TEMPERATURES FROM GUIDANCE VALUES AS MAV/MET TEND TO BE TOO COLD
ON HUMID NIGHTS SUCH AS THIS.
ANOTHER SHORTWAVE TROUGH CROSSES THE AREA TUESDAY NIGHT OR
WEDNESDAY AND WILL PROVIDE ANOTHER CHANCE FOR SHOWERS AND
THUNDERSTORMS. TIMING DIFFERENCES IN THE MODELS MAKES IT DIFFICULT
TO PROVIDE MORE CONFIDENCE VIA HIGHER POP VALUES. GFS AND CMC BOTH
SEEM TO BE SUFFERING FROM FEEDBACK RESULTING FROM CONVECTION. GFS
DEVELOPS A CLOSED 999 MB SURFACE LOW CROSSING THE AREA TUESDAY
NIGHT WHILE THE CMC IS SIMILAR BUT NOT AS STRONG. THIS SOLUTION
SEEMS UNLIKELY AND WAS DISCOUNTED IN FAVOR OF THE ECMWF WHICH
SHOWS A MORE PROGRESSIVE SHORTWAVE CROSSING THE REGION.
A COLD FRONT DROPS SOUTH ACROSS THE AREA ON WEDNESDAY... BRINGING
COOLER AIR DOWN FROM THE GULF OF SAINT LAWRENCE AND EASTERN
CANADA. 850 TEMPERATURES DROP ABOUT 4C WEDNESDAY AS COMPARED TO
TUESDAY AND MAX TEMPERATURES SHOULD REFLECT THIS. HOWEVER...
DOWNSLOPING NORTHWEST WINDS WILL PROVIDE FOR DEEP MIXING ALONG THE
COASTAL PLAIN OF NEW HAMPSHIRE AND SOUTHWEST MAINE... ALLOWING
TEMPERATURES TO CLIMB INTO THE MID TO UPPER 80S FOR ONE MORE DAY.
HIGH PRESSURE BUILDING SOUTH OUT OF EASTERN CANADA WILL BRING AN
EASTERLY TO SOUTHEASTERLY FLOW ON THURSDAY. ECMWF SHOWS A
PRONOUNCED EASTERLY FLOW ACROSS THE AREA WHICH WOULD KEEP A COOL
MARINE AIR MASS IN PLACE. WATER TEMPERATURES OFF THE NEW HAMPSHIRE
COAST AREA IN THE LOW 60S... WHILE WATER TEMPERATURES OFF THE
MIDCOAST OF MAINE ARE IN THE LOW 50S. EVEN THE GFS SHOWS A SOUTH
TO SOUTHEAST FLOW ON THURSDAY WHICH WOULD KEEP MUCH OF MAINE COOL.
AS A RESULT... HAVE GONE WITH COLDER TEMPERATURES FOR WEDNESDAY
WITH HIGHS IN THE LOW 70S ACROSS MAINE TO THE UPPER 70S FOR NEW
HAMPSHIRE. THIS WAS MORE IN LINE WITH THE ECMWF MOS AND HPC.
ALL MODELS NOW IN GOOD AGREEMENT THAT A LARGE SCALE TROUGH WILL BE
APPROACHING THE AREA BY THURSDAY NIGHT... SPREADING BROAD SCALE
LIFT OVER NEW ENGLAND IN COMBINATION WITH AN ONSHORE SOUTHEAST
FLOW. AS A RESULT... INCREASED POPS INTO THE 60 TO 70 PERCENT
RANGE TO REFLECT THE INCREASED CONFIDENCE IN TIMING.
UNFORTUNATELY... THIS BROAD SCALE TROUGH LINGERS TO THE WEST OF
NEW ENGLAND THROUGH THE WEEKEND... LEAVING THE FORECAST AREA WITHIN
THE FAVORABLE AREA FOR RISING MOTION AND PRECIPITATION. TIMING OF
SUBTLE SHORTWAVE TROUGHS WITHIN THE FLOW AND ASSOCIATED SURFACE
FEATURES VARIES AMONG THE MODELS AND IS DIFFICULT TO FORECAST THIS
FAR OUT. AS A RESULT... HAVE INDICATED A CHANCE OF SHOWERS OR
THUNDERSTORMS FROM FRIDAY THROUGH THE WEEKEND.
&&
.AVIATION /23Z SUNDAY THROUGH FRIDAY/...
SHORT TERM...VFR SKIES IN VCTS THIS EVENING. SHOWERS AND
THUNDERSTORMS DIMINISH OVERNIGHT WITH PATCHY DENSE FOG AND STRATUS
DEVELOPING. MOISTURE TRAPPED UNDER AN INVERSION WILL KEEP PERIODS
OF LIFR AND VLIFR CEILINGS IN THE TERMINAL FORECASTS. WEST WINDS
ON MONDAY MAY GUST INTO THE LOWER 20S.
LONG TERM...OVERNIGHT FOG IS POSSIBLE EACH NIGHT IN THE VALLEY
LOCATIONS... AS WELL AS AFTERNOON HAZE AND THUNDERSTORMS THROUGH
TUESDAY. A COLD FRONT BRINGS COOLER AIR IN FOR WEDNESDAY. AN
ONSHORE FLOW ON THURSDAY COULD BRING IFR CONDITIONS PERHAPS
WORSENING TO LIFR BY THURSDAY NIGHT AND FRIDAY IN SHOWERS.
&&
.MARINE...
SHORT TERM...HELD OFF ON A SMALL CRAFT ADVISORY AS GUIDANCE HAS
BEEN OVERDOING WAVE HEIGHTS. THAT SAID A FEW 5-6 FOOTERS MAY
DEVELOP ON THE FAR OUTER WATERS. WINDS WILL STAY BELOW 25 KTS WITH
A FEW GUSTS INTO THE LOWER 20S.
LONG TERM...EXPECT A GENERAL SOUTHWEST FLOW OVER THE WATERS
THROUGH WEDNESDAY THOUGH IT SHOULD REMAIN BELOW 25 KT. GFS MODEL
IS FORECASTING A STRONGER SURFACE LOW TO CROSS INTO THE GULF OF
MAINE FROM THE WEST ON WEDNESDAY BUT THIS IS LIKELY OVERDONE DUE
TO CONVECTION WITHIN THE MODEL. AS A RESULT... WAVE HEIGHTS
GENERATED BY THE WNA WAVE MODEL WERE TOO HIGH ON THE SOUTHWEST
FLOW AHEAD OF THE FRONT. EXPECT WINDS AND WAVES TO STAY BELOW
SMALL CRAFT ADVISORY CONDITIONS AHEAD OF AND BEHIND THE FRONT ON
WEDNESDAY. HIGH PRESSURE DROPS SOUTH OUT OF CANADA AND INTO THE
WESTERN ATLANTIC AND GULF OF MAINE FOR THURSDAY WITH A SOUTHERLY
FLOW RETURNING BY FRIDAY.
&&
.TIDES/COASTAL FLOODING...
A PORTLAND HIGH TIDE OF 11.8 FT IS EXPECTED TONIGHT AT 11:41 PM.
FLOOD STAGE AT PORTLAND IS 12.0 FT. WINDS WILL BECOME WSW TONIGHT
AND NEARLY PARALLEL TO THE COAST. THIS IS NOT A FAVORED DIRECTION
FOR COASTAL EROSION OR SPLASH OVER.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
UPDATE...HANES
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1008 PM EDT SUN JUN 23 2013
.SYNOPSIS...
HIGH PRESSURE BECOMES ANCHORED OFF THE MID ATLANTIC COAST THROUGH
FRIDAY...RESULTING IN A CONTINUED PERIOD OF VERY WARM AND HUMID
CONDITIONS. THERE WILL BE A CHANCE FOR AFTERNOON AND EVENING
THUNDERSTORMS EACH DAY. A COLD FRONT APPROACHES FROM THE WEST
SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
WK TROUGH ALOFT LINGERS INVOF FA THIS EVE. MUCH LESS CNVTN THAN
SAT EVE...AND WHAT THERE HAS BEEN GENLY DISSIPATED IN THE LAST HR
OR TWO. 01Z/24 RUC13 SUGGESTS CONTD (MNLY) SLGT CHC POPS FOR
EXTREME SE PORTION OF FA...AND CNVTN NOW NW OF THE FA TO RMN AWAY
FM THE RGN. OTRW...VRB CLDS TO PCLDY CONDS...WARM AND HUMID
OVRNGT. FG PTNTL IS LO. LO TEMPS FM THE U60S TO L70S.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/...
BERMUDA HIGH PRS BECOMES THE DOMINATE WX FEATURE ACROSS THE SERN
CONUS FOR THE WORKWEEK. ENUF LINGERING MSTR COMBINED WITH DYTME HTNG
RESULTS IN SCT DIURNAL CONVECTION BOTH MON AND TUE WITH THE HIGHEST
CHCS WEST OF CHES BAY. HIGHS MON 85-90...A BIT COOLER ON THE BEACHS.
LOWS MON/TUE NITES U60S-L70S. HIGHS TUE ARND 90...REMAINING IN THE
80S AT THE BEACHES. NOT MUCH OF A TRIGGER SEEN FOR WED AS H5 HGHTS
MAX OUT. WILL KEEP ISLTD POPS FOR NOW. HIGHS WED L90S W OF BAY...U80S
ALONG THE COAST.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A MORE AMPLIFIED PATTERN IS EXPECTED TO DEVELOP OVER NORTH AMERICA
AS WE HEAD INTO LATE IN THE COMING WEEK. A STRONG UPPER RIDGE OF
HIGH PRESSURE WILL DEVELOP OVER THE FOUR CORNERS REGION BY
THURSDAY...THEN REMAINS IN PLACE THROUGH NEXT WEEKEND. MEANWHILE...
A POTENT UPPER LOW DIGGING INTO ONTARIO CANADA ON THURSDAY WILL
CONTINUE TO TRACK SE INTO THE EASTERN GREAT LAKES BY SATURDAY/SUNDAY
AND WILL CARVE OUT A BROAD TROUGH ACROSS THE EASTERN CONUS. AS FAR
AS THE SENSIBLE WX...WARM AND HUMID CONDITIONS ARE EXPECTED TO
CONTINUE THROUGH THE PERIOD. THURSDAY LOOKS TO BE THE LEAST ACTIVE
DAY AS FAR AS CONVECTION (MAINLY SLIGHT CHC POPS)...BEFORE BETTER
ORGANIZATION OF SHOWERS AND TSTMS LOOKS PROBABLE FRI/SAT (40-50%
POPS) AS THE TROUGH SHARPENS OVER THE MID-ATLANTIC. BY SAT
NIGHT/SUNDAY...SFC FRONTAL BOUNDARY LOOKS LIKE IT PUSHES SOUTH OF
THE LOCAL AREA AND STALLS ALONG THE CAROLINA COAST. THIS WOULD FOCUS
CONVECTION MORE ACROSS OUR SOUTHERN AREAS...AND HAVE TRENDED THE
FORECAST IN THAT DIRECTION. HIGHS THROUGH THE PERIOD IN THE UPPER
80S TO LOW 90S AND LOWS MAINLY 70-75.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
A WEAK UPPER LOW PRES SYS OVER WV WILL MOVE NE THRU THE
NIGHT AND SLOWLY WEAKEN. WITH HIGH PRESSURE CENTERED OFF THE MID
ATLANTIC COAST WILL KEEP PLENTY OF LOW LEVEL MOISTURE OVER THE
AREA AS WINDS CONTINUE FROM THE SOUTH. MOST OF THE SHOWERS HAVE
DISSIPATED THIS EVENING BUT AN ISOLATED SHOWER WILL BE POSSIBLE
UNTIL MIDNIGHT. THEN SKIES WILL BE PARTLY CLOUDY WITH A MIX OF MID
AND HIGH LEVEL CLOUDS LEFT FROM THE EARLIER CONVECTION. IT IS
POSSIBLE SOME PATCHY FOG COULD FORM TOWARD MORNING. BEST CHANCES
WILL BE AT RIC PHF AND SBY. WITH STRONGER SURFACE WINDS PERSISTING
THROUGH THE NIGHT ECG AND ORF SHOULD NOT HAVE ANY FOG TONIGHT. IF
THE WIND DOES DIMINISH ECG COULD HAVE SOME PATCHES EARLY IN THE
MORNING. ON MONDAY SCATTERED CU WILL DEVELOP ACROSS THE AREA
DURING THE DAY. ISOLATED CONVECTION WILL AGAIN DEVELOP DURING THE
AFTERNOON. WITH NO STRONG FOCUS FOR THE CONVECTION THESE STORMS
WILL BE ISOLATED AND HARD TO PINPOINT WHERE THEY WILL OCCUR.
HIGH PRESSURE WILL REMAIN ANCHORED OFF THE MID ATLANTIC AND SE
COASTS INTO THE MIDDLE OF NEXT WEEK AND WILL CONTINUE TO STREAM A
MOIST SUBTROPICAL AIRMASS INTO THE REGION. THIS WILL KEEP
UNSETTLED CONDITIONS ACROSS THE AREA WITH RAIN SHOWERS AND
THUNDERSTORMS POSSIBLE EACH DAY.
&&
.MARINE...
MODELS REMAIN IN GOOD AGREEMENT WITH KEEPING BERMUDA HIGH PRESSURE
ANCHORED OFF THE SE COAST THROUGH THE MIDDLE OF THE COMING WEEK.
THIS WEATHER PATTERN WILL KEEP SHWR/TSTM CHANCES IN THE FORECAST
EACH DAY...BUT WILL ALSO BE RATHER BENIGN IN REGARDS TO WIND SPEEDS.
SSW WINDS WILL AVERAGE AOB 15 KT OUTSIDE OF ANY AFTN/EVENING
CONVECTIVE ACTIVITY. EXPECT WAVES OF 1-2 FT ON THE BAY/SOUND/RIVERS
AND SEAS OF GENERALLY 2-4 FT (HIGHEST IN NRN COASTAL WATERS).
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ALB/MPR
NEAR TERM...ALB/MPR
SHORT TERM...MPR
LONG TERM...JDM
AVIATION...JEF/JAB
MARINE...JDM
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1002 PM EDT SUN JUN 23 2013
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE REGION MONDAY.
THE HEAT AND HUMIDITY WILL BUILD THROUGH MIDWEEK UNDER THE
INFLUENCE OF BERMUDA HIGH PRESSURE. AN UPPER TROUGH WILL AMPLIFY
OVER THE GREAT LAKES REGION LATE THIS WEEK AND INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
DIURNAL SHRA/TSRA WERE FEW AND FAR BTWN TAFTN...LKLY DUE TO AN
ABSENCE OF SYNOPTIC SCALE FORCING AND A LT START TO AMS
DSTBLZTN. BUT...AMS DID BECOME UNSTBL BY 21-22Z...AND A FEW TSRA
DVLPD ALNG THE APLCHNS. THESE MULTIPLIED AT THE CONFLUENCE OF
1000-2000 J/KG SBCAPE AND 20 KT BULK SHEAR...AIDED BY WK LLVL
CNVGNC AND OROGRAPHIC LIFT. BOTH RNK/IAD RAOBS DEPICT HOW THE
MTNTOPS WUD BE UNSTBL...AND AREA E OF THE BLURDG CAPPED.
HV MADE UPWD TICK IN POPS/WX IN THE W BASED ON RDR TRENDS. WL CONT
W/ DRY FCST IN THE E. ONLY QUESTION THAT REMAINS WL BE HOW TO
ADDRESS TSRA/SHRA DECAY. HRRR SUGGESTS IT WONT /ALL NGT/... BUT
ITS BEEN IN CATCH-UP MODE MUCH OF THE NGT. OTHER MESO GDNC /WRF-
ARW4 AND RUC13 IN PARTICULAR/ SUGGESTS A QUICK DEMISE. NEW 00Z
NAM KEEPS A SOLN SOMEWHERE IN BTWN. ECHOES HEALTHY ENUF THAT
BELIEVE THEY/LL HANG ON FOR AT LEAST A CPL MORE HRS...BUT HV LOW
CONFIDENCE BYD THAT.
WL HV A MOIST AMS OVNGT /DEWPTS UPR 60S-LWR 70S/ W/ A MOCLR SKY.
THAT SUGGESTS THAT OVNGT FOG DVLPMNT STANDS A BETTER CHC THAN PAST
CPL NGTS. MOST ZONES WL HV PATCHY WORDING. HV BEEFED UP FOG TO
AREAS FOR THOSE LOCATIONS THAT RECEIVED EVNG HRA/TSRA.
LAMP APPEARS TO HV A GOOD FEEL FOR TEMPS...AND HV INCRSD MIN-T
BASED ON LTST RUN. IN PARTICULAR...DOWNTOWNS WONT RADIATE THAT
WELL W/ L70 DEWPTS...WHICH REQD AN INCR OF MIN-T INTO THE 70S.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
500MB TROUGH WILL MOVE EWD THROUGH THE MID-ATLANTIC REGION
MONDAY...AND MODELS INDICATE A POTENTIAL LEE TROUGH DEVELOPING E
OF THE BLUE RIDGE. WARM MOIST AIR CONTINUES TO BE ADVECTED INTO
THE REGION DUE TO AN OFFSHORE BERMUDA HIGH. HIGH TEMPS WARM INTO
THE UPPER 80S/LOW 90S ACROSS THE REGION...WITH MAX HEAT INDICES IN
THE LOW TO MID 90S. DAYTIME SHOWER/TSTM POTENTIAL ONCE AGAIN THROUGH
COMBINATION OF MOIST/UNSTABLE AIRMASS AND THE PASSAGE OF THE UPPER
AND SURFACE TROUGHS.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
HIPRES THAT HAS REMAINED PARKED OFFSHORE WILL SHIFT SOUTHWARD
TOWARD BERMUDA ERY IN THE WEEK. THE NORTHWESTERN PERIPHERY OF THE
RIDGE WILL BREAK DOWN AS A SERIES OF SHORTWAVE TROUGHS CROSS THE
NRN MID-ATLANTIC REGION/NORTHEAST STATES. WAA PATTERN WILL DEVELOP
OVER THE REGION DURING THIS TIME AS WINDS VEER IN RESPONSE TO THE
RIDGE BREAKING DOWN. ABOVE NORMAL TEMPS ARE IN STORE DURING THE
SHORT TERM. FAVORED SLIGHTLY LOWER DEWPOINTS AS DOWNSLOPING W-SWLY
FLOW WILL HELP MIX DOWN DRIER AIR EACH AFTN. NONETHELESS... THE
COMBINED EXPECTED HEAT AND HUMIDITY YIELDS HEAT INDICES IN THE
LOWER TO MID 90S ALONG AND EAST OF I-95 TUE.
GUIDANCE INDICATING THE NEXT MID-LVL SHORTWAVE TROUGH APPROACHING
FROM THE MIDWEST TUE-TUE NGT ALTHOUGH THERE IS UNCERTAINTY IN
TIMING WITH THIS SYSTEM. SHOWERS AND STORMS MAY DEVELOP AGAIN
DURING THE PEAK HEATING HRS.
RETURN FLOW AROUND THE BERMUDA HIGH WILL CONTINUE TO TURN UP THE
HEAT AND HUMIDITY DURING THE MIDDLE OF THE WEEK. THE 00Z GFS PROG
H8 TEMPS OF 20-21C WED AND THU WHILE THE 00Z ECMWF FCST IS A DEGREE
OR TWO LOWER. A COMPROMISE BETWEEN THE TWO MODELS WOULD YIELD MAX
TEMPS IN THE LOW TO MID 90S BOTH DAYS...WHICH WOULD BE THE WARMEST
OF THE YEAR THUS FAR. COMBINED WITH THE HUMIDITY...HEAT INDICES
ARE FCST TO PEAK IN THE MID TO UPPER 90S ALONG AND EAST OF I-95.
CAPPING INVERSION LOOKS STRONGEST ON WED WHILE SYNOPTIC LIFT APPEARS
ABSENT. KEPT WED FCST DRY EAST OF THE BLUE RIDGE ACCORDINGLY WHILE
MTN SHOWERS AND STORMS MAY DEVELOP DURING THE AFTN.
UPPER RIDGE IS FCST TO AMPLIFY OVER THE FOUR CORNERS REGION LATE IN
THE WEEK WHILE DOWNSTREAM TROUGHING DEVELOPS OVER THE GREAT LAKES.
CHANCES FOR SHOWERS AND STORMS WILL INCREASE DURING THIS TIME AS
LIFT AHEAD OF THE TROUGH SPREADS INTO THE MID-ATLANTIC STATES.
UNSETTLED CONDITIONS LOOK TO CONTINUE INTO THE WEEKEND WITH THE
UPPER TROUGH AMPLIFYING OVER THE ERN CONUS.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
VFR FLGT CONDS AT THE AIRPORTS ATTM...AND SHUD REMAIN SO THRU THE
EVNG. DO XPCT MVFR-IFR FOG TO DVLP OVNGT...IMPACTING THE BGNG OF
MRNG PUSHES.
FOG SHUD ERODE BY MID-MRNG...SETTING UP A FAIRLY TYPICAL SUMMER
DAY. XPCT CU DVLPMNT BY ELY AFTN INVOF TROF AXIS...WHICH IN TURN
WUD SUPPORT SCT TSRA. HV 040-050 CLD BASES IN GRIDS...BUT THESE
DONT TRIGGER A CHG GRP IN TAFS. SIMILARLY...THE CONFIDENCE IN
AREAL CVRG AT THIS POINT PRECLUDE A TAF MENTION.
PSBL RADIATIONAL FOG DURING THE ELY MRNG HRS...AND SCT AFTN-EVNG
SHOWERS AND STORMS WL REMAIN THE CALLING CARD INTO MIDWEEK. CHANCES
FOR SHOWER AND STORMS INCREASE LATE IN THE WEEK AS AN UPPER TROUGH
AMPLIFIES OVER THE GREAT LAKES.
&&
.MARINE...
WNDS DECREASED BLO SCA LVLS TAFTN...AND THAT SCA WAS CANX. HWVR...
GDNC SUGGESTING THAT A LLJ WL INDUCE SLY CHANNELING UP THE BAY
THIS EVNG. WL BE SETTING LOOSE A NEW SCA FOR THE BAY UP TO POOLES
ISLAND INCL ERN INLETS FOR THE EVNG HRS-- 8PM-2AM. WNDS SHUD
DECREASE OVNGT-ELY MRNG.
SLY RETURN FLOW AROUND HIPRES WILL CONTINUE THRU MUCH OF WORK WEEK.
WINDS SHOULD BE LGT THRU MIDWEEK BEFORE INCREASING LATE IN THE WEEK
AS A TROUGH APPROACHES FROM THE WEST. WINDS MAY INCREASE TO SCA LVLS
BY THU.
AN ADDTL CONCERN WL BE ALMOST DAILY TSRA CHCS...SPCLY FOR THE
AFTN-EVNG HRS. ALL OF THESE WL POSE LIGHTNING RISKS ALONG W/ LCLY
HIER WNDS/WVS. A FEW OF THESE MAY BE STRONG ENUF TO PROMPT
ISSUANCE OF SPECIAL MARINE WRNGS.
&&
.TIDES/COASTAL FLOODING...
WATER LEVELS HAVE BEEN RUNNING BETWEEN A QUARTER AND A HALF FOOT
ABOVE ASTRONOMICAL TIDE TODAY. THE AFTERNOON HIGH TIDE CYCLE IS
THE LOWER OF THE TWO DIURNAL CYCLES...AND THE TIDE HAS REACHED THE
NORTHER REACHES WITHOUT ANY COASTAL FLOODING CONCERNS. THE MONDAY
MORNING HIDE TIDE WILL BE ASTRONOMICALLY SIMILAR TO SUNDAYS. SINCE
NO TIDAL FLOODING OCCURRED SUNDAY MORNING...ANOMALIES WILL NEED TO
INCREASE IN ORDER TO FLOODING TO OCCUR.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT MONDAY FOR ANZ531>534-
539>541-543.
&&
$$
SYNOPSIS...KCS
NEAR TERM...HTS
SHORT TERM...KCS
LONG TERM...JRK
AVIATION...HTS
MARINE...HTS
TIDES/COASTAL FLOODING...KCS/HTS
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
724 AM EDT SAT JUN 22 2013
.SYNOPSIS...
A WEAK AREA OF LOW PRESSURE WILL LINGER ALONG THE NORTH CAROLINA
COAST THROUGH TODAY. HIGH PRESSURE WILL BE ANCHORED OFF THE MID
ATLANTIC COAST SUNDAY THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
INTERESTING FORECAST CHALLENGES TODAY. HAVE CONVECTION DEVELOPING
ALONG A COASTAL FRONT OVER NORTH CAROLINA AND SLOWLY MOVING NORTH.
THIS IS ASSOCIATED WITH A WEAK PV MAX ALOFT AND CAN BE SEEN ON
WATER VAPOR. MEANWHILE HAVE A WEAK RIDGE OF HIGH PRESSURE ALOFT
JUST TO THE NORTH OF THIS FEATURE. THIS HIGH IS SLOWLY WEAKENING
AND MOVING TO THE EAST. THIS WILL ALLOW THE WEAK TROF TO LIFT
NORTH TODAY. CAN SEE WINDS BECOMING MORE SOUTHEAST ALOFT ON VWP
OBSERVATIONS AROUND THE AREA. THIS WILL ADVECT PLENTY OF MOISTURE
INTO THE SOUTHERN PART OF THE CWA TODAY. WILL FOLLOW THE HRRR IDEA
OF MOVING THE PRECIPITATION FROM NORTH CAROLINA INTO SOUTHEAST
VIRGINIA DURING THE MORNING. COULD SEE SOME BRIEF HEAVY RAIN WITH
SOME OF THE SHOWERS. BY THIS AFTERNOON THE MOISTURE WILL BE PULLED
NORTH OVER MOST OF THE CWA. HOWEVER THE UPPER TROF WILL BE
WEAKENING AND THIS WILL CAUSE THE PRECIPITATION TO MORE SCATTERED.
THIS FOLLOWS THE NAM AND GFS. ALSO THE SREF SHOWS THE BEST CHANCES
FOR PRECIP MOVING TO THE WESTERN SECTIONS OF THE CWA DURING THE
AFTERNOON AND EVENING. SINCE WESTERN AREAS WILL BE SLOWER TO CLOUD
UP WILL HAVE SOME MORE CAPE TO AIDE IN THUNDERSTORM DEVELOPMENT.
AGAIN WITH PLENTY OF MOISTURE AROUND COULD SEE SOME BRIEF HEAVY
DOWNPOURS. TEMPERATURES WILL BE DEPENDENT ON THE AMOUNT OF CLOUD
COVER TODAY. EXPECT TO KEEP MAXES AROUND 80 SOUTHEAST BUT REACH
THE MID 80S ACROSS WESTERN SECTIONS. AGAIN THIS IS CLOSE TO MOS GUIDE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
A SECOND UPPER LOW OVER GEORGIA TODAY WILL SLOWLY LIFT NORTH LATE
TONIGHT AND MOVE ACROSS TO THE WEST OF THE AREA ON SUNDAY. THE
UPPER LOW AGAIN WILL BE WEAKENING AS IT MERGES WITH THE WESTERLY
TO THE NORTH. THIS THIS WILL HELP TO KEEP BEST CHANCES OF SHOWERS
AND THUNDERSTORMS IN THE WESTERN AREAS TONIGHT AND SATURDAY. WITH
THE HIGH PRESSURE CENTERED OFF THE MID ATLANTIC COAST WILL HAVE
MOISTURE FEED OFF THE WATER COMING INTO THE AREA WITH SOME RISE TO
THE EAST WINDS AS THEY APPROACH THE RIDGES TO THE WEST. BY MONDAY
THIS FEATURE IS WEAKENING AND MORE NORTHEAST AWAY FROM THE AREA.
HOWEVER WILL STILL HAVE PLENTY OF MOISTURE ACROSS THE AREA SO WILL
CONTINUE CHANCE TO SLIGHT CHANCE POPS ESPECIALLY ON MONDAY
AFTERNOON WITH THE BEST CHANCES IN THE WEST WHERE THE LOW LEVEL
EAST WINDS WILL BEGIN TO RISE AS THEY APPROACH THE MOUNTAINS TO
THE WEST. WILL GO FAIRLY CLOSE TO MOS GUIDANCE FOR TEMPERATURES
WITH THE WARMEST DAY ON MONDAY AS LESS CLOUD COVER THEN. LOWS AT
NIGHT WILL MAINLY BE IN THE MID TO UPPER 60S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
PERIOD BEGINS WITH A BROAD MID/UPPER LEVEL RIDGE CENTERED OVER
MUCH THE SOUTHERN TIER OF THE CONUS...GRADUALLY EVOLVING INTO A
STRONG RIDGE OVER THE SW STATES WITH A FAIRLY DEEP TROUGH CENTERED
JUST NORTH OF THE GREAT LAKES ACRS ONTARIO CANADA. THIS WILL
TRANSLATE INTO A W/NW UPPER FLOW PATTERN INTO THE MID ATLC STATES.
WHILE A SERIES OF WEAK SHORTWAVES BEGIN TO SHUNT THE RIDGE OFF TO
THE S/SW OF THE CWA TUE/WED...TIMING THESE FEATURES IN THE MEDIUM
RANGE IS QUITE DIFFICULT SO WILL GENLY HAVE ONLY A 20% CHANCE FOR
MAINLY DIURNAL/AFTN/EVENING TSTMS TUE/WED. TEMPERATURES WILL WARM
TO A LITTLE ABOVE AVG FOR LATE JUNE...MAINLY IN THE UPPER 80S TO
LOWER 90S FOR HIGHS WITH LOWS IN THE UPPER 60S TO LOWER 70S. BY
THU/FRI...A MORE DEFINED SFC BOUNDARY SETS UP NOT TOO FAR TO THE
NORTH OF THE CWA...AND 500 MB HEIGHTS SLOWLY FALL...SO HAVE POPS
HIGHER THAN CLIMO BOTH DAYS (ESPECIALLY FRI). HIGHS IN THE UPPER
80S TO LOWER 90S AND LOWS MAINLY FROM 70-75.
&&
.AVIATION /11Z SATURDAY THROUGH WEDNESDAY/...
APART FROM LINGERING IFR/LIFR IVOF KSBY, GENERALLY VFR/MVFR AT
AREA TERMINALS THIS MORNING.
STILL EXPECTING SCT SHRAS TO PUSH NW FROM COASTAL CAROLINAS
TOWARDS COASTAL TERMINALS LATER THIS MORNING, AND HV LEANED ON
HRRR IN TAKING THE PARENT LOW AND THE ASSOCIATED PCPN SHIELD N-NW
INTO NE NC. GIVEN UNCERTAINTY WITH TIMING OF SHRAS, HV GONE WITH
VCSH NOW IN THE TAF AT PHF/ECG/ORF. DO EXPECT TO SEE SOME BREAKS
IN STRATUS AT RIC/SBY AFTER 13-15Z, BUT HV GONE WITH VICINITY SHRA
WORDING AT RIC AFTER 16Z. LOW PRESSURE WL SLOWLY WEAKEN TO OUR
SOUTH,W/ CIGS WL GENERALLY TO RANGE FROM MVFR TO VFR THROUGH THE
AFTN.
OUTLOOK: MORE LATE NIGHT STRATUS IS EXPECTED LATE TONIGHT/SUN
MORNING. OTHERWISE, EXPECT PREDOMINATE VFR CONDITIONS ASIDE FROM
SCATTERED MAINLY DIURNALLY DRIVEN SHRAS SUN AND THROUGH MIDWEEK
AS BREEZY S-SW FLOW REDEVELOPS MON-TUE.
&&
.MARINE...
LATEST OBS CONTINUE TO INDICATE ONSHORE (EAST) FLOW ACRS THE ENTIRE
REGION. WINDS ARE GENLY 15 KT OR LESS (LIGHTEST OVER NORTHERN
AREAS). SEAS CONTINUE TO SLOWLY SUBSIDE THIS MORNING, NOW AOB 4FT
ACROSS THE MID-ATLANTIC WATERS.
NO MAJOR CHANGES TO THE GOING FORECAST WITH THIS PACKAGE. MSAS 3-HR
PRESSURE FALLS CONTINUES TO SHOW SLOW WEAKENING/SLACKENING OF THE
PRESSURE GRADIENT BETWEEN THE INVERTED SFC TROUGH/LOW NEAR KILM AT
08Z AND HIGH PRESSURE OFF NORTHERN MID-ATLANTIC COAST. ACCORDINGLY,
CONTINUE TO EXPECT CONDITIONS TO REMAIN SUB-SCA TODAY. STILL RATHER
UNFAVORABLE BOATING CONDITIONS TODAY, WITH PREDOMINATE LLVL FLOW OUT
OF THE E/NE FLOW AGAIN TODAY WITH SEAS 4 FT AND WAVES 2-3 FT AT THE
MOUTH OF THE BAY.
AS COASTAL FRONT PUSHES BACK WEST THIS AFTN/EVENING, EXPECT WINDS TO
GRADUALLY VEER AROUND TO THE ESE, THEN THE SSE BY 06Z/2A SAT
NIGHT/SUN MORNING WITH SPEEDS AOB 10 KT. THEREAFTER, GOOD MODEL
AGREEMENT IN SETTING UP A RATHER STAGNANT, BUT FAIRLY BENIGN PATTERN
FROM LATE SUN THROUGH THE MIDDLE OF NEXT WEEK. SSW WINDS WL AVERAGE
AOB 15KT OUTSIDE OF ANY DEVELOPING AFTN/EVENING CONVECTION. WAVES
1-2 FT ON THE BAY/SND/RVRS...SEAS GENERALLY 2-4 FT (HIGHEST NORTHERN
COASTAL WATERS).
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR MDZ025.
NC...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR NCZ102.
VA...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR VAZ098>100.
MARINE...NONE.
&&
$$
SYNOPSIS...JAB
NEAR TERM...JAB
SHORT TERM...JAB
LONG TERM...LKB
AVIATION...MAM
MARINE...MAM
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
402 AM EDT SAT JUN 22 2013
.SYNOPSIS...
A WEAK AREA OF LOW PRESSURE WILL LINGER ALONG THE NORTH CAROLINA
COAST THROUGH TODAY. HIGH PRESSURE WILL BE ANCHORED OFF THE MID
ATLANTIC COAST SUNDAY THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
INTERESTING FORECAST CHALLENGES TODAY. HAVE CONVECTION DEVELOPING
ALONG A COASTAL FRONT OVER NORTH CAROLINA AND SLOWLY MOVING NORTH.
THIS IS ASSOCIATED WITH A WEAK PV MAX ALOFT AND CAN BE SEEN ON
WATER VAPOR. MEANWHILE HAVE A WEAK RIDGE OF HIGH PRESSURE ALOFT
JUST TO THE NORTH OF THIS FEATURE. THIS HIGH IS SLOWLY WEAKENING
AND MOVING TO THE EAST. THIS WILL ALLOW THE WEAK TROF TO LIFT
NORTH TODAY. CAN SEE WINDS BECOMING MORE SOUTHEAST ALOFT ON VWP
OBSERVATIONS AROUND THE AREA. THIS WILL ADVECT PLENTY OF MOISTURE
INTO THE SOUTHERN PART OF THE CWA TODAY. WILL FOLLOW THE HRRR IDEA
OF MOVING THE PRECIPITATION FROM NORTH CAROLINA INTO SOUTHEAST
VIRGINIA DURING THE MORNING. COULD SEE SOME BRIEF HEAVY RAIN WITH
SOME OF THE SHOWERS. BY THIS AFTERNOON THE MOISTURE WILL BE PULLED
NORTH OVER MOST OF THE CWA. HOWEVER THE UPPER TROF WILL BE
WEAKENING AND THIS WILL CAUSE THE PRECIPITATION TO MORE SCATTERED.
THIS FOLLOWS THE NAM AND GFS. ALSO THE SREF SHOWS THE BEST CHANCES
FOR PRECIP MOVING TO THE WESTERN SECTIONS OF THE CWA DURING THE
AFTERNOON AND EVENING. SINCE WESTERN AREAS WILL BE SLOWER TO CLOUD
UP WILL HAVE SOME MORE CAPE TO AIDE IN THUNDERSTORM DEVELOPMENT.
AGAIN WITH PLENTY OF MOISTURE AROUND COULD SEE SOME BRIEF HEAVY
DOWNPOURS. TEMPERATURES WILL BE DEPENDENT ON THE AMOUNT OF CLOUD
COVER TODAY. EXPECT TO KEEP MAXES AROUND 80 SOUTHEAST BUT REACH
THE MID 80S ACROSS WESTERN SECTIONS. AGAIN THIS IS CLOSE TO MOS GUIDE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
A SECOND UPPER LOW OVER GEORGIA TODAY WILL SLOWLY LIFT NORTH LATE
TONIGHT AND MOVE ACROSS TO THE WEST OF THE AREA ON SUNDAY. THE
UPPER LOW AGAIN WILL BE WEAKENING AS IT MERGES WITH THE WESTERLY
TO THE NORTH. THIS THIS WILL HELP TO KEEP BEST CHANCES OF SHOWERS
AND THUNDERSTORMS IN THE WESTERN AREAS TONIGHT AND SATURDAY. WITH
THE HIGH PRESSURE CENTERED OFF THE MID ATLANTIC COAST WILL HAVE
MOISTURE FEED OFF THE WATER COMING INTO THE AREA WITH SOME RISE TO
THE EAST WINDS AS THEY APPROACH THE RIDGES TO THE WEST. BY MONDAY
THIS FEATURE IS WEAKENING AND MORE NORTHEAST AWAY FROM THE AREA.
HOWEVER WILL STILL HAVE PLENTY OF MOISTURE ACROSS THE AREA SO WILL
CONTINUE CHANCE TO SLIGHT CHANCE POPS ESPECIALLY ON MONDAY
AFTERNOON WITH THE BEST CHANCES IN THE WEST WHERE THE LOW LEVEL
EAST WINDS WILL BEGIN TO RISE AS THEY APPROACH THE MOUNTAINS TO
THE WEST. WILL GO FAIRLY CLOSE TO MOS GUIDANCE FOR TEMPERATURES
WITH THE WARMEST DAY ON MONDAY AS LESS CLOUD COVER THEN. LOWS AT
NIGHT WILL MAINLY BE IN THE MID TO UPPER 60S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
PERIOD BEGINS WITH A BROAD MID/UPPER LEVEL RIDGE CENTERED OVER
MUCH THE SOUTHERN TIER OF THE CONUS...GRADUALLY EVOLVING INTO A
STRONG RIDGE OVER THE SW STATES WITH A FAIRLY DEEP TROUGH CENTERED
JUST NORTH OF THE GREAT LAKES ACRS ONTARIO CANADA. THIS WILL
TRANSLATE INTO A W/NW UPPER FLOW PATTERN INTO THE MID ATLC STATES.
WHILE A SERIES OF WEAK SHORTWAVES BEGIN TO SHUNT THE RIDGE OFF TO
THE S/SW OF THE CWA TUE/WED...TIMING THESE FEATURES IN THE MEDIUM
RANGE IS QUITE DIFFICULT SO WILL GENLY HAVE ONLY A 20% CHANCE FOR
MAINLY DIURNAL/AFTN/EVENING TSTMS TUE/WED. TEMPERATURES WILL WARM
TO A LITTLE ABOVE AVG FOR LATE JUNE...MAINLY IN THE UPPER 80S TO
LOWER 90S FOR HIGHS WITH LOWS IN THE UPPER 60S TO LOWER 70S. BY
THU/FRI...A MORE DEFINED SFC BOUNDARY SETS UP NOT TOO FAR TO THE
NORTH OF THE CWA...AND 500 MB HEIGHTS SLOWLY FALL...SO HAVE POPS
HIGHER THAN CLIMO BOTH DAYS (ESPECIALLY FRI). HIGHS IN THE UPPER
80S TO LOWER 90S AND LOWS MAINLY FROM 70-75.
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
MODELS CONT TO SHOW A PERSISTENT NE FLOW AHEAD OF APPROACHING SYSTEM
FROM THE SOUTH. ANOTHER STRATUS LAYER DEVELOPING IN ASSOCIATION WITH
REMNANT LLVL MOISTURE TRAPPED BELOW NOCTURNAL INVERSION. THIS WL
LIKELY BRING ANOTHER NIGHT OF IFR VSBYS W/PATCHY FOG. AS LLVL
MOISTURE CONTINUES TO INCREASE, EXPECT IFR TO BE A BIT MORE
WIDESPREAD THIS MORNING THAN THE PREVIOUS TWO.
ASIDE FROM THE FOG, EXPECT SHRAS TO PUSH NW FROM COASTAL CAROLINAS
TOWARDS COASTAL TERMINALS, AND HV LEANED ON HRRR IN TAKING THE
PARENT LOW AND THE ASSOCIATED PCPN SHIELD N-NW INTO NE NC AFTER 12Z
THIS MORNING. PREDOMINATE -RA/SHRA NOW IN THE TAF AT PHF/ECG/ORF
AFTER 13Z, EVENTUALLY REACHING RIC AFTER 15Z. DO EXPECT TO SEE SOME
BREAKS IN STRATUS AT RIC/SBY AFTER 13-15Z, BUT HV GONE WITH VICINITY
SHRA WORDING FOR SCT SHRAS THAT ARE EXPECTED TO DEVELOP BY ERY SAT
AFTN IVOF RIC AS LOW PRESSURE SLOWLY WEAKENS TO OUR SOUTH. CIGS WL
GENERALLY RANGE FROM MVFR TO VFR THROUGH THE AFTN
OUTLOOK: MORE LATE NIGHT STRATUS IS EXPECTED LATE TONIGHT/SUN
MORNING. OTHERWISE, EXPECT PREDOMINATE VFR CONDITIONS ASIDE FROM
SCATTERED MAINLY DIURNALLY DRIVEN SHRAS SUN AND THROUGH MIDWEEK
AS BREEZY S-SW FLOW REDEVELOPS MON-TUE.
&&
.MARINE...
LATEST OBS CONTINUE TO INDICATE ONSHORE (EAST) FLOW ACRS THE ENTIRE
REGION. WINDS ARE GENLY 15 KT OR LESS (LIGHTEST OVER NORTHERN
AREAS). SEAS CONTINUE TO SLOWLY SUBSIDE THIS MORNING, NOW AOB 4FT
ACROSS THE MID-ATLANTIC WATERS.
NO MAJOR CHANGES TO THE GOING FORECAST WITH THIS PACKAGE. MSAS 3-HR
PRESSURE FALLS CONTINUES TO SHOW SLOW WEAKENING/SLACKENING OF THE
PRESSURE GRADIENT BETWEEN THE INVERTED SFC TROUGH/LOW NEAR KILM AT
08Z AND HIGH PRESSURE OFF NORTHERN MID-ATLANTIC COAST. ACCORDINGLY,
CONTINUE TO EXPECT CONDITIONS TO REMAIN SUB-SCA TODAY. STILL RATHER
UNFAVORABLE BOATING CONDITIONS TODAY, WITH PREDOMINATE LLVL FLOW OUT
OF THE E/NE FLOW AGAIN TODAY WITH SEAS 4 FT AND WAVES 2-3 FT AT THE
MOUTH OF THE BAY.
AS COASTAL FRONT PUSHES BACK WEST THIS AFTN/EVENING, EXPECT WINDS TO
GRADUALLY VEER AROUND TO THE ESE, THEN THE SSE BY 06Z/2A SAT
NIGHT/SUN MORNING WITH SPEEDS AOB 10 KT. THEREAFTER, GOOD MODEL
AGREEMENT IN SETTING UP A RATHER STAGNANT, BUT FAIRLY BENIGN PATTERN
FROM LATE SUN THROUGH THE MIDDLE OF NEXT WEEK. SSW WINDS WL AVERAGE
AOB 15KT OUTSIDE OF ANY DEVELOPING AFTN/EVENING CONVECTION. WAVES
1-2 FT ON THE BAY/SND/RVRS...SEAS GENERALLY 2-4 FT (HIGHEST NORTHERN
COASTAL WATERS).
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR MDZ025.
NC...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR NCZ102.
VA...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR VAZ098>100.
MARINE...NONE.
&&
$$
SYNOPSIS...JAB
NEAR TERM...JAB
SHORT TERM...JAB
LONG TERM...LKB
AVIATION...MAM
MARINE...MAM
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
344 AM EDT SAT JUN 22 2013
.SYNOPSIS...
A WEAK AREA OF LOW PRESSURE WILL LINGER ALONG THE NORTH CAROLINA
COAST THROUGH TODAY. HIGH PRESSURE WILL BE ANCHORED OFF THE MID
ATLANTIC COAST SUNDAY THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
INTERESTING FORECAST CHALLENGES TODAY. HAVE CONVECTION DEVELOPING
ALONG A COASTAL FRONT OVER NORTH CAROLINA AND SLOWLY MOVING NORTH.
THIS IS ASSOCIATED WITH A WEAK PV MAX ALOFT AND CAN BE SEEN ON
WATER VAPOR. MEANWHILE HAVE A WEAK RIDGE OF HIGH PRESSURE ALOFT
JUST TO THE NORTH OF THIS FEATURE. THIS HIGH IS SLOWLY WEAKENING
AND MOVING TO THE EAST. THIS WILL ALLOW THE WEAK TROF TO LIFT
NORTH TODAY. CAN SEE WINDS BECOMING MORE SOUTHEAST ALOFT ON VWP
OBSERVATIONS AROUND THE AREA. THIS WILL ADVECT PLENTY OF MOISTURE
INTO THE SOUTHERN PART OF THE CWA TODAY. WILL FOLLOW THE HRRR IDEA
OF MOVING THE PRECIPITATION FROM NORTH CAROLINA INTO SOUTHEAST
VIRGINIA DURING THE MORNING. COULD SEE SOME BRIEF HEAVY RAIN WITH
SOME OF THE SHOWERS. BY THIS AFTERNOON THE MOISTURE WILL BE PULLED
NORTH OVER MOST OF THE CWA. HOWEVER THE UPPER TROF WILL BE
WEAKENING AND THIS WILL CAUSE THE PRECIPITATION TO MORE SCATTERED.
THIS FOLLOWS THE NAM AND GFS. ALSO THE SREF SHOWS THE BEST CHANCES
FOR PRECIP MOVING TO THE WESTERN SECTIONS OF THE CWA DURING THE
AFTERNOON AND EVENING. SINCE WESTERN AREAS WILL BE SLOWER TO CLOUD
UP WILL HAVE SOME MORE CAPE TO AIDE IN THUNDERSTORM DEVELOPMENT.
AGAIN WITH PLENTY OF MOISTURE AROUND COULD SEE SOME BRIEF HEAVY
DOWNPOURS. TEMPERATURES WILL BE DEPENDENT ON THE AMOUNT OF CLOUD
COVER TODAY. EXPECT TO KEEP MAXES AROUND 80 SOUTHEAST BUT REACH
THE MID 80S ACROSS WESTERN SECTIONS. AGAIN THIS IS CLOSE TO MOS GUIDE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
A SECOND UPPER LOW OVER GEORGIA TODAY WILL SLOWLY LIFT NORTH LATE
TONIGHT AND MOVE ACROSS TO THE WEST OF THE AREA ON SUNDAY. THE
UPPER LOW AGAIN WILL BE WEAKENING AS IT MERGES WITH THE WESTERLY
TO THE NORTH. THIS THIS WILL HELP TO KEEP BEST CHANCES OF SHOWERS
AND THUNDERSTORMS IN THE WESTERN AREAS TONIGHT AND SATURDAY. WITH
THE HIGH PRESSURE CENTERED OFF THE MID ATLANTIC COAST WILL HAVE
MOISTURE FEED OFF THE WATER COMING INTO THE AREA WITH SOME RISE TO
THE EAST WINDS AS THEY APPROACH THE RIDGES TO THE WEST. BY MONDAY
THIS FEATURE IS WEAKENING AND MORE NORTHEAST AWAY FROM THE AREA.
HOWEVER WILL STILL HAVE PLENTY OF MOISTURE ACROSS THE AREA SO WILL
CONTINUE CHANCE TO SLIGHT CHANCE POPS ESPECIALLY ON MONDAY
AFTERNOON WITH THE BEST CHANCES IN THE WEST WHERE THE LOW LEVEL
EAST WINDS WILL BEGIN TO RISE AS THEY APPROACH THE MOUNTAINS TO
THE WEST. WILL GO FAIRLY CLOSE TO MOS GUIDANCE FOR TEMPERATURES
WITH THE WARMEST DAY ON MONDAY AS LESS CLOUD COVER THEN. LOWS AT
NIGHT WILL MAINLY BE IN THE MID TO UPPER 60S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
PERIOD BEGINS WITH A BROAD MID/UPPER LEVEL RIDGE CENTERED OVER
MUCH THE SOUTHERN TIER OF THE CONUS...GRADUALLY EVOLVING INTO A
STRONG RIDGE OVER THE SW STATES WITH A FAIRLY DEEP TROUGH CENTERED
JUST NORTH OF THE GREAT LAKES ACRS ONTARIO CANADA. THIS WILL
TRANSLATE INTO A W/NW UPPER FLOW PATTERN INTO THE MID ATLC STATES.
WHILE A SERIES OF WEAK SHORTWAVES BEGIN TO SHUNT THE RIDGE OFF TO
THE S/SW OF THE CWA TUE/WED...TIMING THESE FEATURES IN THE MEDIUM
RANGE IS QUITE DIFFICULT SO WILL GENLY HAVE ONLY A 20% CHANCE FOR
MAINLY DIURNAL/AFTN/EVENING TSTMS TUE/WED. TEMPERATURES WILL WARM
TO A LITTLE ABOVE AVG FOR LATE JUNE...MAINLY IN THE UPPER 80S TO
LOWER 90S FOR HIGHS WITH LOWS IN THE UPPER 60S TO LOWER 70S. BY
THU/FRI...A MORE DEFINED SFC BOUNDARY SETS UP NOT TOO FAR TO THE
NORTH OF THE CWA...AND 500 MB HEIGHTS SLOWLY FALL...SO HAVE POPS
HIGHER THAN CLIMO BOTH DAYS (ESPECIALLY FRI). HIGHS IN THE UPPER
80S TO LOWER 90S AND LOWS MAINLY FROM 70-75.
&&
.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
MODELS CONT TO SHOW A PERSISTENT NE FLOW AHEAD OF APPRCHG SYSTM
FROM THE SOUTH. ANOTHER STRATUS LAYER DVLPNG IN ASSOCIATION WITH
REMNANT LLVL MOISTURE TRAPPED BELOW NOCTURNAL INVERSION. THIS WL
LIKELY BRING ANOTHER NIGHT OF IFR VSBYS W/PATCHY FOG. AS LLVL
MOISTURE CONTINUES TO INCREASE, EXPECT IFR TO BE A BIT MORE
WIDESPREAD THIS MORNING THAN THE PREVIOUS TWO.
ASIDE FROM THE FOG, EXPECT SHRAS TO PUSH NW FROM COASTAL CAROLINAS
TOWARDS COASTAL TERMINALS, AND HV LEANED ON HRRR IN TAKING THE
PARENT LOW AND THE ASSOCIATED PCPN SHIELD N-NW INTO NE NC AFTR 12Z
THIS MORNING. PREDOMINATE -RA/SHRA NOW IN THE TAF AT PHF/ECG/ORF
AFTER 13Z, EVENTUALLY REACHING RIC AFTER 15Z. DO EXPECT TO SEE SOME
BREAKS IN STRATUS AT RIC/SBY AFTER 13-15Z, BUT HV GONE WITH VICINITY
SHRA WORDING FOR SCT SHWRS THAT ARE EXPECTED TO DEVELOP BY ERY SAT
AFTN IVOF RIC AS LOW PRESSURE SLOWLY WEAKENS TO OUR SOUTH. CIGS WL
GENERALLY RANGE FROM MVFR TO VFR THROUGH THE AFTN
OUTLOOK: MORE LATE NIGHT STRATUS IS EXPECTED LATE TONIGHT/SUN
MORNING. OTHERWISE, EXPECT PREDOMINATE VFR CONDITIONS ASIDE FROM
SCATTERED MAINLY DIURNALLY DRIVEN SHRAS SUN AND THROUGH MIDWEEK
AS BREEZY S-SW FLOW REDEVELOPS MON-TUE.
&&
.MARINE...
LATEST OBS CONTINUE TO INDICATE E/NE FLOW ACRS THE ENTIRE REGION.
WINDS ARE GENLY 15 KT OR LESS (LIGHTEST OVER NORTHERN AREAS). SEAS
CONTINUE TO SLOWLY SUBSIDE THIS MORNING, NOW AOB 4FT ACROSS THE
MID-ATLANTIC WATERS.
NO MAJOR CHANGES TO THE GOING FORECAST WITH THIS PACKAGE. MSAS 3-HR
PRESSURE FALLS CONTINUES TO SHOW SLOW WEAKENING/SLACKENING OF THE
PRESSURE GRADIENT BETWEEN THE INVERTED SFC TROUGH/LOW NEAR KILM AT
08Z AND HIGH PRESSURE OFF NORTHERN MID-ATLANTIC COAST. ACCORDINGLY,
CONTINUE TO EXPECT CONDITIONS TO REMAIN SUB-SCA TODAY. STILL RATHER
UNFAVORABLE BOATING CONDITIONS TODAY, WITH PREDOMINATE LLVL FLOW OUT
OF THE E/NE FLOW AGAIN TODAY WITH SEAS 4 FT AND WAVES 2-3 FT AT THE
MOUTH OF THE BAY.
AS COASTAL FRONT, PUSHES BACK WEST, EXPECT WINDS TO GRADUALLY SHIFT
TO THE ESE THEN THE SSE BY SAT NIGHT/SUN (AND SPEEDS WILL AVG AROUND
10 KT). GOOD MODEL AGREEMENT IN SETTING UP A RATHER STAGNANT, BUT
FAIRLY BENIGN PATTERN FROM LATE SUN THROUGH THE MIDDLE OF NEXT WEEK
WITH SSW WINDS AVERAGING 10-15 KT OUTSIDE OF ANY CONVECTION. 1-2 FT
ON THE BAY/SND/RVRS...SEAS GENERALLY 2-4 FT (HIGHEST NORTHERN
COASTAL WATERS).
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR MDZ025.
NC...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR NCZ102.
VA...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR VAZ098>100.
MARINE...NONE.
&&
$$
SYNOPSIS...JAB
NEAR TERM...JAB
SHORT TERM...JAB
LONG TERM...LKB
AVIATION...MAM
MARINE...MAM
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
327 AM EDT SAT JUN 22 2013
.SYNOPSIS...
A WEAK AREA OF LOW PRESSURE WILL LINGER ALONG THE NORTH CAROLINA
COAST THROUGH SATURDAY. HIGH PRESSURE WILL BECOME ANCHORED OFF THE MID
ATLANTIC COAST SUNDAY THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
SFC HIGH PRESSURE EXTENDS OVER THE REGION FROM THE NORTHEAST
TONIGHT. MEANWHILE...AN INVERTED TROUGH/COASTAL FRONT REMAINS OFF
THE CAROLINA COAST. NOT EXPECTING MORE THAN MAINLY ISOLD SHWRS
ACROSS SERN AREAS OVRNGT WITH THE INVERTED TROUGH LINGERING OFF
THE COAST. WE WILL HOWEVER SEE CLOUDS START TO INCREASE FATHER
WEST INTO THE PIEDMONT AS EASTERLY FLOW DEEPENS. NUISANCE LOW
STRATUS/PATCHY FOG WILL ALSO DEVELOP ACROSS THE SOUTHEAST. LOWS
TONIGHT IN THE UPR 50S NW TO THE UPR 60S SERN COASTAL AREAS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY/...
INVERTED TROUGH/COASTAL FRONT WILL LIFT NW AND WEAKEN ALONG THE NC
COAST SATURDAY. BEST LOW-LEVEL MOISTURE STARTS TO SHIFT INLAND
ACROSS SOUTH-CENTRAL VA AND NE NC...AND WE`LL ACTUALLY CARRY CHC
POPS (40-45%) ACROSS THESE AREAS. DESPITE LIMITED FORCING...PWAT`S
AROUND 2 INCHES AND MODEST INSTABILITY (CAPE 1000-1500 J/KG)WILL
HELP GENERATE SOME AFTN THUNDERSTORMS WITH POTENTIAL FOR HEAVY
DOWNPOURS. BECOMING MORE HUMID WITH HIGHS IN THE 80S...EXCEPT
COOLER 70S IMMEDIATE COAST. PCPN WILL WANE WITH THE LOSS OF
DAYTIME HEATING SATURDAY EVENING. LOWS SATURDAY NIGHT IN THE 60S.
A RETURN TO A MORE TYPICAL SUMMERTIME PATTERN IS EXPECTED SUNDAY
INTO MONDAY AS THE COASTAL BOUNDARY IS REPLACED BY BERMUDA HIGH
PRESSURE. THERE WILL BE ENOUGH LINGERING MOISTURE FOR SCT AFTN
CONVECTION BOTH DAYS...ESPECIALLY INLAND...AND WILL COVER THIS
WITH 30% POPS. SEASONABLY WARM AND HUMID WITH HIGHS IN THE 80S TO
AROUND 90...EXCEPT COOLER AT THE BEACHES.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
PERIOD BEGINS WITH A BROAD MID/UPPER LEVEL RIDGE CENTERED OVER
MUCH THE SOUTHERN TIER OF THE CONUS...GRADUALLY EVOLVING INTO A
STRONG RIDGE OVER THE SW STATES WITH A FAIRLY DEEP TROUGH CENTERED
JUST NORTH OF THE GREAT LAKES ACRS ONTARIO CANADA. THIS WILL
TRANSLATE INTO A W/NW UPPER FLOW PATTERN INTO THE MID ATLC STATES.
WHILE A SERIES OF WEAK SHORTWAVES BEGIN TO SHUNT THE RIDGE OFF TO
THE S/SW OF THE CWA TUE/WED...TIMING THESE FEATURES IN THE MEDIUM
RANGE IS QUITE DIFFICULT SO WILL GENLY HAVE ONLY A 20% CHANCE FOR
MAINLY DIURNAL/AFTN/EVENING TSTMS TUE/WED. TEMPERATURES WILL WARM
TO A LITTLE ABOVE AVG FOR LATE JUNE...MAINLY IN THE UPPER 80S TO
LOWER 90S FOR HIGHS WITH LOWS IN THE UPPER 60S TO LOWER 70S. BY
THU/FRI...A MORE DEFINED SFC BOUNDARY SETS UP NOT TOO FAR TO THE
NORTH OF THE CWA...AND 500 MB HEIGHTS SLOWLY FALL...SO HAVE POPS
HIGHER THAN CLIMO BOTH DAYS (ESPECIALLY FRI). HIGHS IN THE UPPER
80S TO LOWER 90S AND LOWS MAINLY FROM 70-75.
&&
.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
MODELS CONT TO SHOW A PERSISTENT NE FLOW AHEAD OF APPRCHG SYSTM
FROM THE SOUTH. ANOTHER STRATUS LAYER DVLPNG IN ASSOCIATION WITH
REMNANT LLVL MOISTURE TRAPPED BELOW NOCTURNAL INVERSION. THIS WL
LIKELY RESULT IN ANOTHER NIGHT OF IFR VSBYS W/PATCHY FOG. AS LLVL
MOISTURE CONTINUES TO INCREASE, EXPECT IFR TO BE A BIT MORE
WIDESPREAD TONIGHT THAN THE PREVIOUS TWO.
ASIDE FROM THE FOG, EXPECT SHRAS TO PUSH NW TOWARDS COASTAL ZONES,
AND HV LEANED ON HRRR IN TAKING THE PARENT LOW AND THE ASSOCIATED
PCPN SHIELD N-NW INTO NE NC AFTR 12Z. PREDOMINATE -RA/SHRA NOW IN
THE TAF AT PHF/ECG/ORF AFTER 13Z. EXPECT SOME BREAKS IN STRATUS AT
RIC/SBY AFTER 13-15Z, BUT HV GONE WITH VICINITY SHRA WORDING FOR
SCT SHWRS THAT ARE EXPECTED TO DEVELOP BY ERY SAT AFTN IVOF RIC
AS LOW PRESSURE SLOWLY WEAKENS TO OUR SOUTH. CIGS WL GENERALLY
RANGE FROM MVFR TO VFR THROUGH THE AFTN
OUTLOOK: MORE LATE NIGHT STRATUS IS EXPECTED LATE TONIGHT/SUN
MORNING. OTHERWISE, EXPECT PREDOMINATE VFR CONDITIONS ASIDE FROM
SCATTERED MAINLY DIURNALLY DRIVEN SHRAS SUN AND THROUGH MIDWEEK
AS BREEZY S-SW FLOW REDEVELOPS MON-TUE.
&&
.MARINE...
LATEST OBS INDICATE E/NE FLOW PREVAILS ACRS THE ENTIRE REGION.
WINDS ARE GENLY 15 KT OR LESS (LIGHTEST OVER NORTHERN AREAS). HAVE
DECIDED TO KEEP SCA IN EFFECT THROUGH 7 PM OVER THE NC COASTAL
WATERS FOR 4-5 FT SEAS (ALTHOUGH FOR THE MOST PART SEAS HAVE
AVERAGED JUST BELOW 5 FT). ELSEWHERE...SEAS ARE 3-4 FT ON THE
COASTAL WATERS, 1-2 FT ON THE BAY/SND/RVRS.
MODELS GENLY FORECAST A SLOW WEAKENING OF THE PRESSURE GRADIENT
BETWEEN THE INVERTED SFC TROUGH/LOW OFF THE NC/SC COAST AND HIGH
PRESSURE OFF THE NJ COAST LATER TONIGHT INTO SAT...SO CONDITIONS
SHOULD NE SUB-SCA THROUGHOUT. THE E/NE FLOW WITH SEAS 4 FT AND
WAVES 2-3 FT AT THE MOUTH OF THE BAY WILL STILL TRANSLATE TO LESS THAN
IDEAL BOATING CONDITIONS ACROSS THE LOWER BAY AND COASTAL WATERS
INTO SAT AFTN HOWEVER.
WINDS GRADUALLY SHIFT TO THE ESE THEN THE SSE BY SAT NIGHT/SUN
(AND SPEEDS WILL AVG AROUND 10 KT). A RATHER STAGNANT, BUT FAIRLY
BENIGN PATTERN IS EXPECTED TO TAKE SHAPE FROM LATE SUN THROUGH THE
MIDDLE OF NEXT WEEK WITH SSW WINDS AVERAGING 10-15 KT OUTSIDE OF
ANY CONVECTION. 1-2 FT ON THE BAY/SND/RVRS...SEAS GENERALLY 2-4
FT (HIGHEST NORTHERN COASTAL WATERS).
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR MDZ025.
NC...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR NCZ102.
VA...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR VAZ098>100.
MARINE...NONE.
&&
$$
SYNOPSIS...JDM
NEAR TERM...JDM/MAS
SHORT TERM...JDM/TMG
LONG TERM...LKB
AVIATION...MAM
MARINE...LKB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
747 PM EDT SUN JUN 23 2013
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 418 PM EDT SUN JUN 23 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL LOW OVER SE
SASK INTO SRN MANITOBA WITH A SHORTWAVE TROUGH EXTENDING INTO ERN ND
AND NW MN. AT THE SFC...A 999MB SFC LOW WAS LOCATED OVER THE NW CORNER
OF MN WITH A WARM FRONT EXTENDING INTO SRN LAKE SUPERIOR. CLEARING
AND AFTERNOON HEATING HAS PUSHED TEMPS INTO THE LOWER 80S OVER WRN
UPPER MI RESULTING IN MLCAPE VALUES TO AROUND 1500 J/KG. SCT
SHRA/TSRA WERE DEVELOPING OVER WRN LAKE SUPERIOR INTO NW UPPER MI
CLOSEST TO THE FORCING ASSOCIATED WITH THE ND/MN SHRTWV.
EXPECT THAT SCT SHRA/SHRA WILL CONTINUE TO DEVELOP BACK THROUGH WRN
UPPER MI LATE THIS AFTERNOON AS A WEAK TROUGH MOVES INTO THE
AREA...PER HIGH RES MODELS. INSTABILITY ALONG WITH 30-35 KT 0-6KM
SHEAR AND 20-25 KT 0-1KM SHEAR COULD SUPPORT AT LEAST ISOLD
STRONG/SEVERE STORMS...WITH STRONG WIND GUSTS AS THE MAIN HAZARD
GIVEN DCAPE VALUES INTO THE 500-1000 J/KG RANGE. EXPECT THAT THE
SHRA/TSRA WILL SPREAD INTO CNTRL UPPER MI BY 21Z-23Z AND THEN
DISSIPATE AND WEAKEN BY LATE EVENING AS THE SHRA/TSRA MOVE TOWARD
THE ERN CWA...AWAY FROM THE THE STRONGER INSTABILITY AND THE SHRTWV
FORCING.
AS THE SHORTWAVE AND LOW MOVE INTO NRN ONTARIO THE DRY SLOT AND
STRONG MID LEVEL DRYING WILL SPREAD ACROSS THE REGION LATE TONIGHT
INTO MONDAY. THIS WILL HELP MINIMIZE CHANCES FOR ADDITIONAL
CONVECTION. WITH SUNSHINE AND 850 MB TEMPS STILL AROUND 15C...TEMPS
WILL AGAIN CLIMB INTO THE LOWER 80S.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 418 PM EDT SUN JUN 23 2013
GENERAL AGREEMENT IN OVERALL LOOK OF LARGER SCALE PATTERN INTO NEXT
WEEKEND THOUGH DETAILS AND SPECIFICS REMAIN UNCERTAIN. TO START ON
MONDAY EVENING...FAIRLY STRONG SHORTWAVE TROUGH WILL BE HEADING EAST
ACROSS NORTHERN ONTARIO LEAVING RIDGING IN ITS WAKE OVER NORTHERN
PLAINS. SFC FRONT AND POOL OF SFC-H85 MOISTURE ALONG THE BOUNDARY
DRIVES SOUTH OF CWA BY LATE MONDAY EVENING RESULTING IN GENERALLY
QUIET AND LESS HUMID WEATHER INTO MUCH OF TUESDAY. GFS AND ECMWF
AGREE HERE...WHILE THE GEM-NH AND THE UKMET DO NOT PUSH WARM FRONT
FAR ENOUGH SOUTH TO KEEP CHANCES OF SHRA/TSRA OUT OF CWA. WILL LEAN
ON THE MORE CONSISTENT ECMWF IDEA WHICH IS SUPPORTED BY WPC HAND
DRAWN SFC MAP.
WITH WARM FRONT AND EDGE OF SFC BASED-MUCAPE MOST LIKELY STILL SOUTH
BY TUESDAY AFTN...WONDER IF MOST AREAS STAY DRY THROUGH TUESDAY. ANY
SHRA/TSRA THAT FORM MONDAY NIGHT INTO TUESDAY MORNING SHOULD STAY
SOUTH OF CWA PER H85-H3 THICKNESSES AND FORWARD PROPAGATING CORFIDI
VECTORS AND EVEN THE MEAN LAYER WIND. INTO TUESDAY NIGHT...ECMWF AND
GFS STILL HAVE SHORTWAVE CRASHING THROUGH TOP EDGE OF LARGER SCALE
RIDGING. WAVE MAY AID IN BRINGING AT LEAST H85 FRONT FAR ENOUGH
NORTH THAT SOUTHERN TIER COULD BE AFFECTED BY SHRA/TSRA TUESDAY
NIGHT AND MUCH OF THE CWA COULD SEE SHRA/TSRA ON WEDNESDAY. GFS
STRONGER WITH THIS WAVE SO MUCH THAT IT PUSHES SFC WARM FRONT INTO
CWA ON WEDNESDAY. PV ANAMOLY THAT GFS CARRIES IN HERE ON WEDNESDAY
TRACKS BACK TO SOUTH EDGE OF STRONG UPR LOW OVER THE ALLUTIANS THIS
MORNING. WAVE LOOKS PRETTY VIGOROUS ON WV LOOP. ECMWF HAS BETTER
TRACK RECORD IN THE EXTENDED...BUT WILL BLEND SOME OF THE GFS IDEA
IN AS WELL SINCE IT SEEMS TO HAVE SOME MERIT.
TROUGH AND HIGHER SFC-H85 DWPNTS PUSH THROUGH AREA WEDNESDAY EVENING
AND COOLER AIR ARRIVES LATER ON THURSDAY. GFS QUICKER AND STRONGER
AS WELL AS FARTHER SOUTH WITH SHORTWAVE TROUGH DIGGING ACROSS UPR
LAKES ON THURSDAY WHILE THE ECMWF SHOWS MORE SEPARATION BTWN THE
WAVE ON WEDNESDAY AND THAT STRONGER TROUGHING. GFS HAS TENDENCY TO
BRING SYSTEMS IN TOO QUICKLY AND ITS SOLUTION VERIFYING AT 12Z
THURSDAY HAS SHOWN TOO MUCH INCONSISTENCY TO PUT MUCH STOCK IN IT AT
THIS POINT. ECMWF HAS TRENDED A BIT SHAPRER WITH TROUGH BUT OVERALL
HAS BEEN MUCH MORE CONSISTENT THAN GFS. WILL PREFER THAT IDEA FOR
NOW. RESULT WILL BE SCT SHRA/TSRA...MAYBE EVEN NMRS FOR A TIME
WEDNESDAY OR WEDNESDAY EVENING...THEN DIMINISHING WITH LOSS OF
INSTABILITY AXIS LATER WEDNESDAY NIGHT. POTENTIAL FOR ANOTHER ROUND
OF SCT SHRA/TSRA DURING PEAK HEATING ON THURSDAY AS AIRMASS OVER THE
REGION IS STILL A BIT UNSTABLE /MLCAPES UP TO 1000 J/KG/ WHILE WNW
FLOW ALOFT INCREASES ON SOUTH EDGE OF UPPER TROUGH. LIGHT AND
VARIABLE SFC WINDS COULD RESULT IN LAKE BREEZE CONVERGENCE AS WELL.
ALWAYS HAVE TO WATCH OUT FOR WNW-NW FLOW ALOFT AS THAT PATTERN WITH
SUFFICIENT INSTABILITY IS ONE THAT CAN RESULT IN AT LEAST SOME
CHANCE OF SEVERE WEATHER.
UPPER TROUGH DOMINATES ON FRIDAY WITH A BIT COOLER AND UNSETTLED
WEATHER. NO TSRA EXPECTED ON FRIDAY AS COOLER TEMPS ALOFT/STEEPER
LAPSE RATES SETUP FROM NORTHERN ONTARIO INTO THE LOWER GREAT LAKES.
COULD BE SHRA AT TIMES THOUGH AS SMALLER SCALE SHORTWAVES ROTATE
AROUND PRIMARY UPPER TROUGH. FRIDAY NIGHT INTO SATURDAY MAY BE KIND
OF BLUSTERY ALONG LK SUPERIOR AND WITH ONSHORE WINDS SWIM RISK MAY
BE HIGHER TO START THE WEEKEND. SMALL CHANCES OF SHRA MAY LINGER
INTO SATURDAY AS WELL. TEMPS SOME AREAS FRIDAY INTO SATURDAY MAY
END UP MORE THAN 10 DEGREES BELOW NORMAL. HIGH PRESSURE BUILDS IN
FOR LATER IN THE WEEKEND...RESULTING IN TEMPS BOUNCING UP AT LEAST
TOWARD NORMAL. NEXT SHORTWAVE IN WNW FLOW APPEARS LATE IN THE WEEKEND
SO HAVE POPS MOVING BACK IN FOR LATE SUNDAY. NO REAL WARM TEMPERATURES
SEEN NEXT WEEKEND OR EVEN INTO EARLY NEXT WEEK AS TROUGHING ALOFT
OVER EASTERN CANADA AND GREAT LAKES KEEPS WARM AIR RESTRICTED TO
WESTERN AND SOUTHERN PORTIONS OF CONUS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 747 PM EDT SUN JUN 23 2013
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE NEAR KSAW THROUGH
EARLY EVENING. OTHERWISE...EXPECT PRIMARILY VFR CONDITIONS THROUGH
THE NIGHT. LATER THIS EVENING WITH ABUNDANT MOISTURE IN PLACE EXPECT
SOME PATCHY FOG TO DEVELOP TOWARDS MORNING AT BOTH KCMX/KSAW AS HAS
BEEN SEEN AT BOTH SITES THROUGH THE WEEK. DO NOT EXPECT EITHER SITE
TO DROP BELOW MVFR IN TERMS OF VISIBILITY. OTHERWISE...EXPECT FAIRLY
QUIET CONDITIONS THROUGH THE TAF PERIOD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 418 PM EDT SUN JUN 23 2013
WINDS SHOULD REMAIN 25 KTS OR LESS THROUGH THE UPCOMING WEEK. MAIN
HAZARD WILL BE SCT THUNDERSTORMS TONIGHT AND FOG. DENSE
FOG ADVISORIES HAVE BEEN EXTENDED THROUGH TONIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 5 AM EDT /4 AM CDT/ MONDAY FOR LSZ162-
263>267.
LAKE MICHIGAN...
DENSE FOG ADVISORY UNTIL 8 AM EDT MONDAY FOR LMZ248-250.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...MCD
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
426 PM EDT SAT JUN 22 2013
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 423 PM EDT SAT JUN 22 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
ALBERTA INTO THE NRN ROCKIES AND A RIDGE OVER THE CNTRL GREAT LAKES
RESULTING IN SW FLOW FROM THE PLAINS THROUGH THE UPPER MS VALLEY.
THE MOST PROMINENT UPSTREAM SHORTWAVE TROUGH WAS MOVING THROUGH WRN
WYOMING. WIDESPREAD LOW LEVEL MOISTURE AND CLOUDS PREVAILED NORTH OF
A WARM FRONT EXTENDING FROM SE MN THROUGH CNTRL WI. TO THE SOUTH OF
THE FRONT...TEMPS OVER ERN IA HAD CLIMBED INTO THE MID AND UPPER 80S
WITH DEWPOINTS INTO THE LOWER 70S.
TONIGHT...AS THE MID LEVEL RIDGE BUILDS TO THE EAST...THE SW FLOW
PATTERN WILL ALLOW THE SFC-850 MB WARM FRONT TO PUSH TO THE NORTH.
ALTHOUGH CONVECTION IS EXPECTED TO REDEVELOP ALONG OR AHEAD OF THE
WARM FRONT THIS EVENING.....UNCERTAINTY WITH THE TIMING/POSITION OF
ANY UPSTREAM SHRTWVS AND THE EVOLUTION OF CONVECTION IS
HIGH. WITH THE FOCUS FOR MOISTURE/LOW LEVEL THETA-E ADVECTION
SHIFTING FROM THE UPPER MS VALLEY TOWARD THE CWA...POPS INCREASE
INTO THE WRN CWA AND ACROSS UPPER MICHIGAN BUT ARE STILL LIMITED TO
CHANCE CATEGORY. SINCE MUCAPE VALUES ARE ONLY EXPECTED IN THE
400-800 J/KG RANGE...ONLY ISOLD TSRA WERE MENTIONED. POTENTIAL FOR
STRONG OR SEVERE STORMS SHOULD REMAIN FARTHER SOUTH NEAR THE GREATER
INSTABILITY.
SUNDAY...AS THE WY SHRTWV LIFTS INTO THE NRN PLAINS A STRENGTHENING
SFC LOW OVER THE ERN DAKOTAS WILL BRING INCREASING SRLY FLOW INTO
THE WRN LAKES AND SHOULD FINALLY PUSH THE WARM FRONT NORTH OF UPPER
MI. HOWEVER...CINH WILL ALSO INCREASE WITH 700 MB TEMPS INTO THE
10C-12C RANGE. SO...TEMPS WILL CLIMB WELL ABOVE NORMAL INTO THE
MID/UPPER 80S AND CONVECTION POTENTIAL WILL BE LIMITED OVER THE
CNTRL AND EAST. HOWEVER...SHRA/TSRA WILL INCREASE AGAIN BY MIDDAY
SUN INTO SUN AFTERNOON AS MODELS CONTINUE TO SUGGEST A WEAK
SHRTWV/IMPULSE COULD BRUSH MAINLY THE WRN CWA. MLCAPE VALUES INTO
THE 1500-2000 J/KG RANGE COMBINED WITH 0-6KM SHEAR VALUES IN THE
30-40 KT RANGE COULD SUPPORT SOME STRONGER AND POSSIBLY SEVERE
STORMS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 423 PM EDT SAT JUN 22 2013
UPPER AIR PATTERN SUNDAY NIGHT INDICATES A DEEPER TROUGH LIFTING
INTO SCNTRL CANADA WITH RIDGING CENTERED OVER OHIO VALLEY. SFC WARM
FRONT SHOULD BE VCNTY OF UPR MICHIGAN/LK SUPERIOR. H85 FRONT ALSO
SHOULD BE MAINLY NORTH OF CWA. FORECAST WILL ASSUME THAT IS GOING TO
BE THE CASE AS LAST COUPLE DAYS...SFC WARM FRONT HAS REMAINED
FARTHER SOUTH THAN FORECAST THANKS TO TSRA AND ASSOCIATED RAIN
COOLED OUTFLOW. DO THINK FRONT WILL HAVE BETTER SHOT OF MAKING IT
NORTH OF UPR MICHIGAN BY SUNDAY NIGHT DUE TO SW FLOW AHEAD OF
STRONGER SHORTWAVE ALOFT. BASED ON INITIAL FOCUS REGION FOR
SHRA/TSRA AND H7 WINDS/FORWARD PROPAGATING CORFIDI VECTORS AND
850-300MB THICKNESS...EXPECT CHANCES OF SHRA/TSRA SUNDAY NIGHT TO
MAINLY BE OVER WESTERN THIRD OF UPR MICHIGAN AND ACROSS LK
SUPERIOR ON EDGE OF H7 CAPPING TIED TO ELEVATED MIXED LAYER /EML/.
AS MENTIONED IN SHORT TERM DISCUSSION...BASED ON AVAILABLE
INSTABILITY AND DEEP LAYER SHEAR...THERE WILL BE POTENTIAL FOR STRONG
OR SEVERE STORMS SUNDAY EVENING OVER THE WEST. NAM/ECMWF FITS THIS
EXPECTATION THE BEST WHILE THE GEM-NH AND GFS SEEM TO SHOW QPF TOO
FAR EAST INTO THE CAPPED AREA. THOSE IDEAS WOULD HAVE BETTER CHANCE
OF VERIFYING IF THE SFC-H85 FRONTS END UP FARTHER SOUTH THAN FORECAST.
CHANCES FOR SHRA/TSRA ON MONDAY LIKELY HIGHEST DURING THE MORNING
AND HIGHEST OVER THE EASTERN CWA ON EDGE OF CAPPING THAT WILL BE
BEING SHUNTED TO THE EAST AND SOUTH AT THAT TIME AS H85 WINDS VEER
MORE WESTERLY. WILD CARD FOR MONDAY IS IF TAIL OF SHORTWAVE AND
ASSOCIATED HEIGHT FALLS MOVING ACROSS NORTHERN LK SUPERIOR ARE
SUFFICIENT ENOUGH TO TRIGGER OTHER SHRA/TSRA ON EDGE OF CAPPING AND
MUCAPE GRADIENT JUST UPSTREAM AND/OR JUST SOUTH OF UPR MICHIGAN. A
PRETTY LOW CHANCE OF THIS...BUT IF IT WOULD HAPPEN THEN THERE IS
POSSIBILITY OF SHRA/TSRA COMPLEX IMPACTING PARTS OF CWA ON MONDAY
MORNING. INTO MONDAY AFTN...WIND FIELD BECOMES GENERALLY LIGHT AND
VARIABLE WHICH OPENS DOOR FOR LK BREEZE SHRA/TSRA OVER MAINLY CNTRL
UPR MICHIGAN /MQT-ESC-P53/. KEPT A SMALL POP IN THERE. WOULD BE VERY
LOW CHANCE IF THERE IS MORE FORMIDABLE CONVECTION AROUND MONDAY
MORNING AS SUBSIDENCE LATER IN THE DAY WOULD LIKELY PUT CAP ON ANY
ADDITIONAL SHRA/TSRA. HIGHS ON MONDAY COULD SURGE INTO THE LOW-MID
80S OVER SCNTRL BUT SHOULD STAY IN THE MID-UPR 70S ELSEWHERE. WILL
BECOME INCREASINGLY LESS HUMID LATER MONDAY AFTN OVER WESTERN UPR
MICHIGAN. DEVELOPING ONSHORE FLOW IN AFTN MAY RESULT IN SOME FOG IN
IMMEDIATE LK SUPERIOR SHORELINE AREAS EAST OF MQT.
GOING TO GO FOR PERIOD OF QUIET WEATHER MONDAY NIGHT AND FOR MOST OF
TUESDAY AS WELL. SFC-H85 FRONTAL BOUNDARIES AND ASSOCIATED SHRA/TSRA
LOOK TO SETTLE WELL TO SOUTH OF CWA MONDAY EVENING. OTHER THAN
WEAKER SHORTWAVES TRAVELLING THROUGH GENERAL FLAT RIDGING
ALOFT...THERE REALLY IS NOT A STRONG ENOUGH FEATURE TO BRING THE
FRONTS BACK TO THE NORTH. EXPECT SHRA/TSRA TO STAY OVER SOUTHERN
HALF OF MN AND WI MONDAY NIGHT INTO TUESDAY MORNING. PERHAPS ISOLD
SHRA/TSRA MAKE INTO TO THE WI BORDER LATE TUESDAY AFTN/EVENING AS
SFC-H85 FRONTS TRY TO LIFT BACK TO THE NORTH OUT AHEAD OF LARGER
SCALE TROUGHING MOVING ACROSS SCNTRL CANADA. ON THE OTHER
HAND...MAYBE THIS NEXT ROUND OF SHRA/TSRA REMAINS MAINLY TO THE
SOUTH OF UPR MICHIGAN SINCE SFC FRONT/MORE ABUNDANT INSTABILITY
STAYS TO THE SOUTH. TOUGH TO SAY REALLY AS AT THE SAME TIME...H7
TEMPS PROGGED TO SURGE UPWARD AS CAPPING BUILDS JUST TO THE SOUTH
OF UPR MICHIGAN. KEPT POPS CHANCE ALL AREAS...WITH HIGHEST CHANCES
CONFINED TO SOUTH CENTRAL UPR MICHIGAN. KEPT SIMILAR IDEA GOING
WEDNESDAY AS WELL WITH HIGHEST POPS ALONG WI BORDER INTO SCNTRL UPR
MICHIGAN. WENT WITH MORE BROADBRUSHED APPROACH TO POPS WEDNESDAY
NIGHT INTO THURSDAY AS COLD FRONT PRESSES IN FROM MANITOBA/ONTARIO
AHEAD OF DEEPER UPR LEVEL TROUGH THAT DIGS INTO UPR LAKES REGION
THURSDAY NIGHT INTO FRIDAY.
WARM AND HUMID AIRMASS EXITS TO THE EAST BY THURSDAY NIGHT. HIGH
TEMPS FOR FRIDAY AND NEXT SATURDAY SHOULD END UP BLO NORMAL ALL
AREAS. COULD SEE CHANCES OF MAINLY RAIN SHOWERS /NO TSRA/ AS UPR
TROUGH SETTLES ACROSS THE AREA. GUSTY NORTHWEST WINDS LIKELY AS WELL
ALONG LK SUPERIOR ON FRIDAY AS THE COOLER AIR ARRIVES. PATTERN WILL
FAVOR POTENTIAL FOR INCREASED SWIM RISK ON THE LAKE SUPERIOR BEACHES
FOR FRIDAY. ARRIVAL OF THE COOLER AND DRIER AIRMASS SHOULD FINALLY
SCOUR OUT THE FOG ON LK SUPERIOR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 155 PM EDT SAT JUN 22 2013
WITH ABUNDANT LOW-LEVEL MOISTURE LINGERING OVER THE REGION NORTH OF
A WARM FRONT...EXPECT LOWER CIGS TO PEVAIL THIS AFTERNOON. UPSLOPE ENE
FLOW INTO SAW WILL KEEP LIFR/IFR CONDITIONS IN PLACE TIL LATE THIS
AFTERNOON WHEN DAYTIME HEATING/MIXING HELPS BRING IMPROVEMENT INTO
THE MVFR RANGE. LOSS OF DAYTIME HEATING AND CONTINUED COOL EASTERLY
UPSLOPE FLOW SHOULD BRING A RETURN OF FOG/LIFR CONDITIONS TO KCMX IN
THE EVENING. DOWNSLOPE SE FLOW SHOULD MAY KEEP MVFR CONDITIONS AT
KIWD INTO THE EVENING. AS FOR PCPN...SHRA/TSRA POTENTIAL IS VERY
UNCERTAIN AND IS EXPECTED TO BE MORE SCT OR ISOLD IF ANY DEVELOPS
LATE THIS AFTERNOON OR EVENING. CONFIDENCE WAS NOT HIGH ENOUGH TO
INCLUDE MENTION IN THE TAF AT THIS ISSUANCE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 423 PM EDT SAT JUN 22 2013
WINDS SHOULD REMAIN 25 KTS OR LESS THROUGH THE UPCOMING WEEK. MAIN
HAZARDS FOR MOST OF THE TIME WILL CONTINUE TO BE THUNDERSTORMS AND
FOG. DENSE FOG ADVISORIES HAVE BEEN EXTENDED INTO SUNDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 10 AM EDT /9 AM CDT/ SUNDAY FOR LSZ162-
240>250-263>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...JLB
MARINE...JLA
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
201 AM EDT SAT JUN 22 2013
.AVIATION...
//DISCUSSION...
THE QUESTION ON WHAT WILL BECOME OF THE CONVECTION OVER SOUTHERN
WISCONSIN IS THE MAIN FOCUS FOR THE TAFS THIS MORNING. THE
UPSTREAM THUNDERSTORM ACTIVITY SEEMS TO BE FOCUSING ON EDGE OF
CAP (SEE 00Z KDVN RAOB) FORCED BY LOCALIZED CVA. THE SHORTWAVE
ENERGY IS A RECYCLED CONVECTIVE VORT MAX THAT HAS EMERGED FROM THE
SOUTH. COLUMN MEAN FLOW OVER SOUTHERN WISCONSIN IS ACTUALLY QUITE
WEAK AS THE LOW LEVEL JET IS WEAK WITHIN THE UPPER LEVEL RIDGE.
CORFIDI VECTORS THROUGH MUCH OF THE MORNING ARE FROM THE EAST
WHICH CORRESPONDS WELL TO THE BACKBUILDING BEHAVIOR SEEN RECENTLY.
THIS LEAVES SERIOUS DOUBT IN POTENTIAL FOR THUNDERSTORMS TO
MIGRATE EASTWARD INTO SOUTHEASTERN MICHIGAN. NEVERTHELESS..00Z
KDTX RAOB SUGGESTS THAT EFFERVESCING WEAK CONVECTION MAY BE
POSSIBLE THIS MORNING OVER THE NORTHERN CWA WITH NOTHING MORE THAN
A MODEST INCREASE IN MOISTURE AND ASSOCIATED CLOUD TOP COOLING.
FOR NOW WILL MAINTAIN FORECAST CONTINUITY AND CONVERT PROB30 TO
TEMPO.
AT KDTW...QUIET WEATHER IS EXPECTED THROUGH THE MORNING HOURS. ANY
SHOWER OR THUNDERSTORM ACTIVITY THAT DEVELOPS IS EXPECTED TO
REMAIN NORTH OF THE DETROIT METRO AREA CLOSER TO THE MOISTURE
GRADIENTS.
//DTW THRESHOLD THREATS...
* LOW CONFIDENCE FOR A BRIEF PERIOD OF CEILINGS AT 5KFT SATURDAY
MORNING.
* LOW CONFIDENCE IN THUNDERSTORMS SATURDAY AFTERNOON.
&&
.PREV DISCUSSION...ISSUED 958 PM EDT FRI JUN 21 2013
UPDATE...
CLOUD SHIELD FROM THE LONG-LIVED MCS...NOW POSITIONED OVER SW
INDIANA WHITTLING INTO THE DEEP INSTABILITY RESERVOIR...HAS
QUICKLY DISSIPATED OVER SOUTHEAST MICHIGAN IN THE BROAD UPPER-
LEVEL ANTI-CYCLONIC FLOW. RETURN DEEP THETA-E ADVECTION IS
ALREADY EVIDENT...IN THE FORM OF FRESH SHOWER DEVELOPMENT...NEAR
LAKE MICHIGAN. THIS INITIAL FEATURE IS EXPECTED TO SLIDE EAST AND
SLOWLY WASH OUT IN THE POST-MIDNIGHT HOURS. WHILE THIS OCCURS
GREATER THETA-E ADVECTION IN THE 925-850MB LAYER...OWING FROM AN
INCREASING NOCTURNAL LOW-LEVEL JET...WILL FILTER INTO THE LOWER
PENINSULA LATE TONIGHT. LATEST RAP SOLUTIONS INDICATE 0-1KM MLCAPE
VALUES CLIMBING TO NEAR 1KJ/KG BY DAYBREAK AND INCREASE FROM THERE
THROUGH THE MORNING HOURS. THE SHARP INSTABILITY GRADIENT WILL
QUICKLY TAKE RESIDENCE ACROSS AREAS ALONG AND NORTH OF I-69.
EXPECT NEW CONVECTION TO CONTINUE TO CYCLE ALONG THE SURGE OF
INSTABILITY ACROSS WISCONSIN AND WESTERN LOWER MICHIGAN AS WARM
FRONTAL DYNAMICS WILL AID IN FORCING ASCENT. FARTHER UPSTREAM
ORGANIZED CONVECTION SHOULD CONTINUE ALONG THE SHARP INSTABILITY
GRADIENT OVER SOUTHEAST MINNESOTA AND CENTRAL WISCONSIN. EXPECT
SOME OF THIS ACTIVITY TO CHURN EAST ALONG THE WELL DEFINED
INSTABILITY GRADIENT THROUGHOUT THE NIGHT AND INTO SATURDAY
MORNING.
PREV DISCUSSION...ISSUED 347 PM EDT FRI JUN 21 2013
SHORT TERM...TONIGHT
SOUTHEAST MICHIGAN REMAINS ON THE OUTER FRINGE OF THE UPPER LEVEL
RIDGE CENTERED OVER MISSOURI (SECOND RIDGE CENTER OVER MID
ATLANTIC)...WHICH MAKES FOR A DIFFICULT FORECAST AS 500 MB HEIGHT
HOVERS AROUND THE NORMALLY CRITICAL VALUE OF 588 DAM.
NONE-THE-LESS...700 MB TEMPS REMAIN BELOW 10 C THROUGH
TONIGHT...WHICH SUGGEST ACTIVITY IS POSSIBLE/NOT FULLY CAPPED.
THE MASSIVE AND LONG LIVED MCS WHICH DEVELOPED OVER THE WESTERN
GREAT LAKES THIS MORNING CONTINUES TO WEAKEN...WITH REMNANT 500 MB
LOW/TROUGH TRACKING THROUGH NORTHERN LOWER MICHIGAN EARLY THIS
EVENING. LATEST RADAR TRENDS SUGGEST A FEW SHOWERS AND POSSIBLE
THUNDERSTORMS MAY SURVIVE THE TRIP ACROSS THE STATE...AS THERE IS
SOME MODEST CAPES (SB CAPES OF 1000 J/KG)/INSTABILITY THE RAIN
COOLED AIRMASS WILL BE MOVING INTO. ON THE FLIP SIDE...DEW PTS ARE
MIXING DOWN INTO THE 50S ACROSS NORTHERN INDIANA/NW OHIO AND INTO
PARTS OF SOUTHERN LOWER MICHIGAN...INDICATIVE OF THE 850-700 MB
THETA-E TROUGH ASSOCIATED WITH THE RIDGE CENTER OVER THE MID
ATLANTIC STATES...AND THUS THE DIRECTION THE FORECAST IS SKEWED WITH
JUST SLIGHT CHANCE POPS SOUTH TO CHANCE POPS NORTH.
THE QUESTION THEN BECOMES WHAT TO DO WITH TONIGHT...AS WISCONSIN LOW
TRACKS NORTHEAST...ALLOWING FOR A DECENT 850 MB JET OF 40+ KNOT TO
SET UP OVER NORTHERN LOWER MICHIGAN THIS EVENING. GOOD
DESTABILIZATION TO REDEVELOP OVER THE WESTERN GREAT LAKES...WITH
ANOTHER MCS DEVELOPING OVER THE EASTERN DAKOTAS THIS AFTERNOON...AND
IT CERTAINLY IS POSSIBLE THIS COMPLEX WILL ARRIVE IN A WEAKENED
STATE OVER LOWER MICHIGAN LATER TONIGHT...DESPITE THE 12Z NAM
INDICATING DISSIPATION OVER WISCONSIN THIS EVENING. EVEN IF THIS
DOES NOT OCCUR...STILL A CHANCE THE LOW LEVEL JET WILL TRIGGER A FEW
SHOWERS/THUNDERSTORMS WITH MOISTURE AXIS MOVING
OVERHEAD...ESPECIALLY AS ONE HEADS NORTH TOWARD SAGINAW BAY...CLOSER
TO THE REMNANT WEAK FRONTAL BOUNDARY AND BETTER MOISTURE TRANSPORT.
WITH INCREASING LOW LEVEL MOISTURE...MINS IN THE 60S ARE EXPECTED.
LONG TERM... SATURDAY THROUGH FRIDAY
EVOLUTION OF CONVECTION OVER THE MIDWEST AND GREAT LAKES REMAINS THE
PRIMARY FORECAST CHALLENGE THROUGH THE WEEKEND AS A MID SUMMER AIR
MASS SPREADS OVER THE REGION. SATELLITE IMAGERY AND MODEL ANALYSIS
FIELDS INDICATE THE CONVECTIVE COMPLEX FROM THIS MORNING YIELDED A
SUBSTANTIAL MCV NOW OVER THE NORTHERN GREAT LAKES BUT WHICH WILL
MOVE EAST IN TIME FOR EITHER THE ONGOING NORTHERN PLAINS
CONVECTION TO MOVE EASTWARD OR FOR A NEW ROUND OF NOCTURNAL
DEVELOPMENT OVER THE UPPER MIDWEST TONIGHT. THE GENESIS REGION
WILL BE FARTHER EAST COMPARED TO LAST NIGHT, MIGRATING WITH THE
LARGE SCALE SURFACE TROUGH FROM THE NORTHERN PLAINS/DAKOTAS INTO
MINNESOTA/NORTHERN WISCONSIN. EXPECT A RESURGENT LOW LEVEL JET TO
FORCE NEW CONVECTION BY LATE THIS EVENING, OR SUPPORT THE ONGOING
STORMS MOVING IN FROM THE DAKOTAS, EITHER OF WHICH WILL HAVE A
CHANCE TO REACH CENTRAL/SE MICHIGAN DURING SATURDAY MORNING.
INITIATION/PERSISTENCE OF EVENING CONVECTION WILL BE FAVORED ALONG
EDGE OF THE MID LEVEL CAP, SUPPORTED BY OBSERVATIONS TO BE ROUGHLY
IN THE 8-10C RANGE AT 700 MB AND AROUND 18C AT 850 MB. THIS, ALONG
WITH A WESTERLY MEAN FLOW WILL SET UP A GENERAL WEST TO EAST
DEVELOPMENT OF STORMS INTO SATURDAY MORNING. LOWER MICHIGAN WILL
BE MORE RECEPTIVE TO MCS PERSISTENCE BY THEN DUE TO INCREASED
POTENTIAL INSTABILITY IN THE WARM SECTOR OVER THE REGION, AT LEAST
COMPARED TO THIS MORNING, BUT WITH THE INSTABILITY AXIS GENERALLY
WEAKENING FROM WEST TO EAST OVER THE GREAT LAKES. THE KEY TO
COVERAGE IN SE MICHIGAN MIGHT BE TIED TO THE INSTABILITY
GRADIENT/CAP TAKING ON MORE OF WEST TO EAST CONFIGURATION AS THE
WARM FRONT MOVES INTO THE NORTHERN GREAT LAKES, WHICH FAVORS THE
TRI CITIES AND NORTHERN THUMB WITH THE GREATEST CHANCE OF STORMS.
SEVERE WEATHER POTENTIAL REMAINS ON THE LOW SIDE AS A MATURE
COMPLEX WILL BE POSSIBLE BUT, AS MENTIONED ABOVE, EXPECTED TO BE
MOVING INTO WEAKER ENVIRONMENT OF INSTABILITY AND MID LEVEL LAPSE
RATES. BULK SHEAR IN THE 0-6 KM LAYER IS ALSO UNFAVORABLE AT
GENERALLY LESS THAN 20 KNOTS AS THE LARGER SCALE RIDGE BUILDS OVER
THE REGION.
CONDITIONS WILL BECOME INCREASINGLY CAPPED FOR THUNDERSTORM ACTIVITY
DURING SATURDAY AFTERNOON THROUGH SUNDAY. AFTER NOCTURNAL CONVECTION
EXITS/DISSIPATES SATURDAY MORNING, MODERATE SOUTHWEST LOW LEVEL FLOW
WILL DISSIPATE ANY LINGERING OUTFLOW BOUNDARIES AND WORK AGAINST
LAKE BREEZE FORMATION/INLAND PENETRATION. ALL OF THIS WILL OCCUR AS
THE UPPER LEVEL RIDGE BUILDS OVER LOWER MICHIGAN AND REINFORCES WARM
AIR THROUGH THE MID LEVELS. THE NEW 12Z RUNS ARE IN GOOD GENERAL
AGREEMENT ON THE CHARACTER OF THE RIDGE WITH 500 MB HEIGHT BUILDING
INTO THE 588-591 RANGE BY SATURDAY NIGHT INTO SUNDAY. THIS WILL
SUPPORT THE RECENTLY ADVERTISED HEAT AND HUMIDITY FOR THE REST OF
THE WEEKEND. SURFACE DEWPOINT PUSHING 70F WILL BOOST HEAT INDEX INTO
THE LOWER 90S SATURDAY AFTERNOON AND TOWARD THE MID 90S SUNDAY WITH
GREATER CONFIDENCE THAT CLOUD COVER WILL HAVE MINIMAL IMPACT ON
AFTERNOON MAX TEMPS.
THE LARGE SCALE PATTERN WILL SUPPORT PERSISTENCE OF WARM AND HUMID
CONDITIONS INTO NEXT WEEK. THE MAIN SOURCE OF FORECAST UNCERTAINTY
DURING MONDAY AND TUESDAY WILL BE WITH THE EVOLUTION OF A WEAK UPPER
LEVEL CIRCULATION NOW OVER THE SOUTHEAST STATES. GLOBAL MODELS
INDICATE THIS FEATURE SLOWLY DRIFTING INTO THE WESTERLIES AS A NEW
SHORT WAVE SLIDES INTO NORTHERN ONTARIO. THE ABSORPTION OF THE UPPER
CIRCULATION OVER THE EASTERN GREAT LAKES WILL COMBINE WITH THE
POTENTIAL FOR A DECAYING FRONTAL BOUNDARY TO SETTLE OVER THE REGION
AND REQUIRE A CONTINUED CHANCE MENTION OF SHOWERS AND STORMS. THERE
REALLY IS NO CONVINCING MODEL SOLUTION THAT OFFERS A SIGNIFICANT
CHANGE OF AIR MASS DURING THE SECOND HALF OF NEXT WEEK UNTIL
PERHAPS FRIDAY. THE LONG WAVE PATTERN IS SHOWN TO RETROGRADE
ENOUGH BY THEN AND OPEN THE DOOR ON A CANADIAN AIR MASS HEADING
INTO NEXT WEEKEND.
MARINE...
GENERALLY LIGHT SOUTHERLY WINDS WILL CONTINUE THROUGH THE
WEEKEND...LEADING TO UNSTABLE ATMOSPHERIC CONDITIONS WHICH COULD
TRIGGER THUNDERSTORMS FROM TIME TO TIME. OUTSIDE OF THUNDERSTORM
ACTIVITY, HIGHLY STABLE CONDITIONS CREATED BY THE WARM AIR OVER THE
COOL LAKE WATER WILL MAINTAIN A MUTED RESPONSE TO THE WAVE GROWTH.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....CB
UPDATE.......MANN
SHORT TERM...SF
LONG TERM....BT
MARINE.......SF
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DULUTH MN
917 AM CDT SAT JUN 22 2013
.UPDATE...
WE UPDATED GRIDS FOR THE SHORT TERM TO ACCOUNT FOR LATEST RADAR
TRENDS. WE REDUCED POPS OVER THE NEXT COUPLE HOURS...BUT DO EXPECT
INCREASING COVERAGE AS THE DAY PROGRESSES. LATEST SPC OUTLOOK
REDUCED THE NORTHWARD EXTENT OF THE SLIGHT RISK AREA FOR SEVERE
STORMS. GIVEN HOW FAR SOUTH THE WARM FRONT IS ATTM...WE AGREE
WITH THAT MOVE. ALTHOUGH SOME STRONGER STORMS MAY STILL OCCUR OVER
THE CWA THIS AFTERNOON. WE ALSO HAVE CONCERNS THAT SOME STRONGER
STORMS MAY ARRIVE TONIGHT AS THE FRONT TRIES TO MOVE NORTH AGAIN
AND WITH AN INCREASING LLJ. A QUICK LOOK AT THE LATEST NAM REVEALS
INCREASING INSTABILITY AND DEEP LAYER SHEAR OVERNIGHT...SO STRONG
TO POSSIBLY SEVERE STORMS MAY ALSO BE POSSIBLE LATE
TONIGHT...MAINLY OVER THE SOUTHERN HALF OF THE CWA.
THE VISIBILITY HAS RISEN IN SILVER BAY...GRAND MARAIS...ASHLAND
AND IRONWOOD THIS MORNING. IF THESE TRENDS HOLD...WE MAY BE ABLE
TO DROP THE DENSE FOG ADVISORY FOR PORTIONS OF THE NORTH AND SOUTH
SHORES. THE ONSHORE FLOW IS STRONGER IN THE TWIN PORTS AREA...SO
FOG SHOULD REMAIN HERE THE LONGEST.
&&
.PREV DISCUSSION... /ISSUED 701 AM CDT SAT JUN 22 2013/
AVIATION...12Z TAF ISSUANCE...
LOW PRESSURE SYSTEM OVER SWRN MN AND ERN NEB WILL CONTINUE TO
SPREAD SHOWERS AND STORMS THROUGH THE REGION TODAY AND TONIGHT.
THE EXACT TIMING AND PLACEMENT OF PRECIP WILL BE DIFFICULT TO NAIL
DOWN...SO KEPT WITH VCSH LATE MORNING AND AFTERNOON...AND ANOTHER
ROUND OF SHOWERS LATE TONIGHT. HAVE FOG THIS MORNING AT DLH LIFTING
BY 15/17Z...BUT KEEPING LOW CLOUDS IN THROUGH MOST OF THE DAY AND
FOG RETURNING TONIGHT. E/NE WINDS WILL BECOME GUSTY THIS AFTERNOON.
PREV DISCUSSION... /ISSUED 409 AM CDT SAT JUN 22 2013/
SHORT TERM...TODAY THROUGH SUNDAY.
THE FOCUS FOR TODAY THROUGH SUNDAY WILL CONTINUE TO BE PCPN
POTENTIAL...AS WELL AS THE CONTINUED POTENTIAL FOR FOG AND
DRIZZLE. PORTIONS OF THE CWA ARE ALSO IN THE SLIGHT RISK FOR
SEVERE WEATHER TODAY AND TONIGHT.
AT 330 AM...IT WAS ESSENTIALLY DRY ACROSS THE NORTHLAND. THERE
WERE A FEW LIGHT SHOWERS NORTH OF THE IRON RANGE...AND ALSO IN NW
WI. WIDESPREAD SHOWERS AND THUNDERSTORMS CONTINUED FROM EASTERN
SOUTH DAKOTA...THROUGH CENTRAL AND SOUTHERN MN AND SOUTHERN WI
WITH WIDESPREAD MCS ACTIVITY IN THOSE AREAS. DENSE FOG CONTINUED
NEAR LAKE SUPERIOR AND HAVE ISSUED A DENSE FOG ADVISORY FOR LAND
AND WATER AREAS.
THE BIG QUESTION IS THE EVOLUTION OF THE WIDESPREAD SHOWERS AND
THUNDERSTORMS TO THE SOUTH OF THE AREA. AS EXPECTED WITH THIS TYPE
OF PATTERN...THE MODELS REALLY DO NOT HAVE A HANDLE ON THE CURRENT
PRECIPITATION. THERE ARE A FEW EXCEPTIONS...INCLUDING THE 4 KM WRF
AND THE 06Z HRRR RAPID REFRESH. BOTH HAVE A RELATIVELY DECENT
HANDLE ON THE CURRENT PRECIPITATION TRENDS...AND BOTH BRING THE
PRECIPITATION NORTH AND EASTWARD INTO OUR CWA. HAVE DONE SOME
DRAMATIC MODIFICATIONS TO POPS AND WEATHER FOR TODAY. THE TWO HIGH
RESOLUTION MODELS ACTUALLY LIFT IT INTO THE CWA BUT DECREASE THE
PRECIPITATION GRADUALLY. WILL KEEP THIS TREND GOING. HAVE ALSO
ADDED AREAS OF DRIZZLE AND DENSE FOG NEAR LAKE SUPERIOR...WHICH
WILL LIKELY CONTINUE THROUGHOUT THE DAY IN SOME FORM.
FOR LATER TODAY AND TONIGHT...MOST OF THE MODEL SOLUTIONS DO BRING
A DRAMATIC INCREASE IN PRECIPITATION...AS A FRONTAL BOUNDARY
STRETCHES FROM SW TO NE ACROSS THE AREA. WILL INCREASE POPS LATER
TODAY AND TONIGHT. COULD STILL SEE SOME STRONG TO SEVERE STORMS IF
WE ARE ABLE TO SEE ENOUGH DAYTIME HEATING FOR SURFACE BASED
CONVECTION. THE FAIRLY HIGH CHANCE OF SHOWERS AND THUNDERSTORMS
WILL ALSO CONTINUE ON SUNDAY...AS THE FRONT REMAINS IN THE AREA.
WILL DEFINITELY NEED TO CONTINUE TO MONITOR THE THREAT OF FLOODING
ACROSS THE AREA. PRECIPITABLE WATER VALUES ARE ON THE ORDER OF 1.8
INCHES TODAY INTO SUNDAY...SO THERE IS ABUNDANT AVAILABLE MOISTURE.
TEMPS WILL BE TROUBLESOME TODAY BASED ON CLOUDS AND PCPN TRENDS.
OVERALL WE SHOULD SEE 70S FOR MOST AREAS TODAY AND SOME 80S
SUNDAY. IT WILL BE DRAMATICALLY COOLER NEAR LAKE SUPERIOR WITH
SOME FAIRLY STRONG NORTHEAST WINDS.
LONG TERM...SUNDAY NIGHT THROUGH FRIDAY NIGHT...
UPPER LOW AND CO-LOCATED SFC LOW WILL MOVE FROM SRN MANITOBA AND WRN
ONTARIO TO THE E/NE ACROSS NRN/CENTRAL ONTARIO SUNDAY NIGHT AND
MONDAY MORNING. A TRAILING COLD FRONT WILL SWEEP ACROSS THE UPPER
MIDWEST AND BRING RAIN SHOWERS AND THUNDERSTORMS TO MUCH OF THE
NORTHLAND THROUGH MON MORNING. HIGH PRESSURE IS EXPECTED TO BUILD IN
ACROSS NRN MN LATE MON AFTERNOON AND INTO MONDAY NIGHT. THIS WILL
ALLOW CONDITIONS TO REMAIN QUIET...AT LEAST UNTIL TUE MORNING WHEN
THE NEXT FRONT IS EXPECTED TO LIFT NWD THROUGH THE REGION AND SPREAD
ANOTHER ROUND OF SHOWERS AND STORMS THROUGH WED EVENING. AN AREA OF
LOW PRESSURE WILL DEVELOP OVER S-CENTRAL CANADA...ON THE NWRN FLANK
OF THE SFC TROUGH/WARM FRONT...AND MOVE EWD INTO NRN ONTARIO ON
THURSDAY. THIS LOW PRESSURE WILL DRAW IN SLIGHTLY COOLER AIR FROM
NRN CANADA AND MODIFY LOW LEVEL THERMAL PROFILES ACROSS NRN MN
ENOUGH TO TRIGGER SHOWERS AND STORMS ACROSS THE REGION THROUGH
FRIDAY.
TEMPERATURES MONDAY THROUGH THURSDAY WILL BE WARM WITH HIGHS IN THE
70S AND 80S...AND 60S AROUND THE PERIPHERY OF LAKE SUPERIOR.
OVERNIGHT LOWS WILL BE MILD WITH TEMPS DROPPING INTO THE UPPER 50S
AND 60S.
AVIATION.../06Z TAF ISSUANCE/
NEXT FEW HOURS A CLUSTER OF THUNDERSTORMS MAY AFFECT KHYR WITH IFR
CIGS AND MVFR VSBYS. OTHERWISE...LAKE EFFECTS ARE PRODUCING
STRATUS OVER MOST OF THE REGION WITH MVFR CIGS...WITH LIFR AT KDLH.
STRATUS HAS LOTS OF HOLES STILL AT KBRD AND KHYR...AND KINL HAS
NOT BEEN AFFECTED AT ALL. THIS STRATUS LAYER SHOULD CONTINUE
OVERNIGHT WITH SOME MVFR FOG ALSO EXPECTED. KDLH TO REMAIN LIFR IN
FOG AND STRATUS WITH THE LIGHT EAST WINDS CONTINUING. WINDS TO
TURN MORE SOUTHERLY SATURDAY IN THE 15Z-18Z TIME RANGE AND EXPECT
CIGS TO IMPROVE DURING THE DAY. SHOWERS AND THUNDERSTORMS ARE
EXPECTED DURING THE AFTERNOON FOR AT LEAST A SHORT TIME...BUT
TIMING AND LOCATION STILL UNCERTAIN SO HAVE LEFT AS VCTS FOR NOW.
&&
.POINT TEMPS/POPS...
DLH 62 57 77 60 / 60 70 60 60
INL 75 62 77 58 / 50 50 60 60
BRD 76 67 82 61 / 60 70 50 50
HYR 78 69 86 63 / 60 70 60 60
ASX 73 61 83 61 / 70 70 60 60
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR MNZ020-021-
037.
WI...DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR WIZ001>004.
LS...DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR LSZ121-
140>148.
SMALL CRAFT ADVISORY UNTIL 10 PM CDT THIS EVENING FOR LSZ143>146.
&&
$$
SHORT TERM...MELDE
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
701 AM CDT SAT JUN 22 2013
.AVIATION...12Z TAF ISSUANCE...
LOW PRESSURE SYSTEM OVER SWRN MN AND ERN NEB WILL CONTINUE TO
SPREAD SHOWERS AND STORMS THROUGH THE REGION TODAY AND TONIGHT.
THE EXACT TIMING AND PLACEMENT OF PRECIP WILL BE DIFFICULT TO NAIL
DOWN...SO KEPT WITH VCSH LATE MORNING AND AFTERNOON...AND ANOTHER
ROUND OF SHOWERS LATE TONIGHT. HAVE FOG THIS MORNING AT DLH LIFTING
BY 15/17Z...BUT KEEPING LOW CLOUDS IN THROUGH MOST OF THE DAY AND
FOG RETURNING TONIGHT. E/NE WINDS WILL BECOME GUSTY THIS AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 409 AM CDT SAT JUN 22 2013/
SHORT TERM...TODAY THROUGH SUNDAY.
THE FOCUS FOR TODAY THROUGH SUNDAY WILL CONTINUE TO BE PCPN
POTENTIAL...AS WELL AS THE CONTINUED POTENTIAL FOR FOG AND
DRIZZLE. PORTIONS OF THE CWA ARE ALSO IN THE SLIGHT RISK FOR
SEVERE WEATHER TODAY AND TONIGHT.
AT 330 AM...IT WAS ESSENTIALLY DRY ACROSS THE NORTHLAND. THERE
WERE A FEW LIGHT SHOWERS NORTH OF THE IRON RANGE...AND ALSO IN NW
WI. WIDESPREAD SHOWERS AND THUNDERSTORMS CONTINUED FROM EASTERN
SOUTH DAKOTA...THROUGH CENTRAL AND SOUTHERN MN AND SOUTHERN WI
WITH WIDESPREAD MCS ACTIVITY IN THOSE AREAS. DENSE FOG CONTINUED
NEAR LAKE SUPERIOR AND HAVE ISSUED A DENSE FOG ADVISORY FOR LAND
AND WATER AREAS.
THE BIG QUESTION IS THE EVOLUTION OF THE WIDESPREAD SHOWERS AND
THUNDERSTORMS TO THE SOUTH OF THE AREA. AS EXPECTED WITH THIS TYPE
OF PATTERN...THE MODELS REALLY DO NOT HAVE A HANDLE ON THE CURRENT
PRECIPITATION. THERE ARE A FEW EXCEPTIONS...INCLUDING THE 4 KM WRF
AND THE 06Z HRRR RAPID REFRESH. BOTH HAVE A RELATIVELY DECENT
HANDLE ON THE CURRENT PRECIPITATION TRENDS...AND BOTH BRING THE
PRECIPITATION NORTH AND EASTWARD INTO OUR CWA. HAVE DONE SOME
DRAMATIC MODIFICATIONS TO POPS AND WEATHER FOR TODAY. THE TWO HIGH
RESOLUTION MODELS ACTUALLY LIFT IT INTO THE CWA BUT DECREASE THE
PRECIPITATION GRADUALLY. WILL KEEP THIS TREND GOING. HAVE ALSO
ADDED AREAS OF DRIZZLE AND DENSE FOG NEAR LAKE SUPERIOR...WHICH
WILL LIKELY CONTINUE THROUGHOUT THE DAY IN SOME FORM.
FOR LATER TODAY AND TONIGHT...MOST OF THE MODEL SOLUTIONS DO BRING
A DRAMATIC INCREASE IN PRECIPITATION...AS A FRONTAL BOUNDARY
STRETCHES FROM SW TO NE ACROSS THE AREA. WILL INCREASE POPS LATER
TODAY AND TONIGHT. COULD STILL SEE SOME STRONG TO SEVERE STORMS IF
WE ARE ABLE TO SEE ENOUGH DAYTIME HEATING FOR SURFACE BASED
CONVECTION. THE FAIRLY HIGH CHANCE OF SHOWERS AND THUNDERSTORMS
WILL ALSO CONTINUE ON SUNDAY...AS THE FRONT REMAINS IN THE AREA.
WILL DEFINITELY NEED TO CONTINUE TO MONITOR THE THREAT OF FLOODING
ACROSS THE AREA. PRECIPITABLE WATER VALUES ARE ON THE ORDER OF 1.8
INCHES TODAY INTO SUNDAY...SO THERE IS ABUNDANT AVAILABLE MOISTURE.
TEMPS WILL BE TROUBLESOME TODAY BASED ON CLOUDS AND PCPN TRENDS.
OVERALL WE SHOULD SEE 70S FOR MOST AREAS TODAY AND SOME 80S
SUNDAY. IT WILL BE DRAMATICALLY COOLER NEAR LAKE SUPERIOR WITH
SOME FAIRLY STRONG NORTHEAST WINDS.
LONG TERM...SUNDAY NIGHT THROUGH FRIDAY NIGHT...
UPPER LOW AND CO-LOCATED SFC LOW WILL MOVE FROM SRN MANITOBA AND WRN
ONTARIO TO THE E/NE ACROSS NRN/CENTRAL ONTARIO SUNDAY NIGHT AND
MONDAY MORNING. A TRAILING COLD FRONT WILL SWEEP ACROSS THE UPPER
MIDWEST AND BRING RAIN SHOWERS AND THUNDERSTORMS TO MUCH OF THE
NORTHLAND THROUGH MON MORNING. HIGH PRESSURE IS EXPECTED TO BUILD IN
ACROSS NRN MN LATE MON AFTERNOON AND INTO MONDAY NIGHT. THIS WILL
ALLOW CONDITIONS TO REMAIN QUIET...AT LEAST UNTIL TUE MORNING WHEN
THE NEXT FRONT IS EXPECTED TO LIFT NWD THROUGH THE REGION AND SPREAD
ANOTHER ROUND OF SHOWERS AND STORMS THROUGH WED EVENING. AN AREA OF
LOW PRESSURE WILL DEVELOP OVER S-CENTRAL CANADA...ON THE NWRN FLANK
OF THE SFC TROUGH/WARM FRONT...AND MOVE EWD INTO NRN ONTARIO ON
THURSDAY. THIS LOW PRESSURE WILL DRAW IN SLIGHTLY COOLER AIR FROM
NRN CANADA AND MODIFY LOW LEVEL THERMAL PROFILES ACROSS NRN MN
ENOUGH TO TRIGGER SHOWERS AND STORMS ACROSS THE REGION THROUGH
FRIDAY.
TEMPERATURES MONDAY THROUGH THURSDAY WILL BE WARM WITH HIGHS IN THE
70S AND 80S...AND 60S AROUND THE PERIPHERY OF LAKE SUPERIOR.
OVERNIGHT LOWS WILL BE MILD WITH TEMPS DROPPING INTO THE UPPER 50S
AND 60S.
AVIATION.../06Z TAF ISSUANCE/
NEXT FEW HOURS A CLUSTER OF THUNDERSTORMS MAY AFFECT KHYR WITH IFR
CIGS AND MVFR VSBYS. OTHERWISE...LAKE EFFECTS ARE PRODUCING
STRATUS OVER MOST OF THE REGION WITH MVFR CIGS...WITH LIFR AT KDLH.
STRATUS HAS LOTS OF HOLES STILL AT KBRD AND KHYR...AND KINL HAS
NOT BEEN AFFECTED AT ALL. THIS STRATUS LAYER SHOULD CONTINUE
OVERNIGHT WITH SOME MVFR FOG ALSO EXPECTED. KDLH TO REMAIN LIFR IN
FOG AND STRATUS WITH THE LIGHT EAST WINDS CONTINUING. WINDS TO
TURN MORE SOUTHERLY SATURDAY IN THE 15Z-18Z TIME RANGE AND EXPECT
CIGS TO IMPROVE DURING THE DAY. SHOWERS AND THUNDERSTORMS ARE
EXPECTED DURING THE AFTERNOON FOR AT LEAST A SHORT TIME...BUT
TIMING AND LOCATION STILL UNCERTAIN SO HAVE LEFT AS VCTS FOR NOW.
&&
.POINT TEMPS/POPS...
DLH 66 57 77 60 / 60 70 60 60
INL 75 62 77 58 / 50 50 60 60
BRD 76 67 82 61 / 70 70 50 50
HYR 78 69 86 63 / 60 70 60 60
ASX 73 61 83 61 / 60 70 60 60
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR MNZ020-021-
037.
WI...DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR WIZ001>004.
LS...DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR LSZ121-
140>148.
SMALL CRAFT ADVISORY UNTIL 10 PM CDT THIS EVENING FOR LSZ143>146.
&&
$$
SHORT TERM...DAP
LONG TERM....TENTINGER
AVIATION...TENTINGER
AREA FORECAST DISCUSSION
NWS DULUTH MN
409 AM CDT SAT JUN 22 2013
.SHORT TERM...TODAY THROUGH SUNDAY.
THE FOCUS FOR TODAY THROUGH SUNDAY WILL CONTINUE TO BE PCPN
POTENTIAL...AS WELL AS THE CONTINUED POTENTIAL FOR FOG AND
DRIZZLE. PORTIONS OF THE CWA ARE ALSO IN THE SLIGHT RISK FOR
SEVERE WEATHER TODAY AND TONIGHT.
AT 330 AM...IT WAS ESSENTIALLY DRY ACROSS THE NORTHLAND. THERE
WERE A FEW LIGHT SHOWERS NORTH OF THE IRON RANGE...AND ALSO IN NW
WI. WIDESPREAD SHOWERS AND THUNDERSTORMS CONTINUED FROM EASTERN
SOUTH DAKOTA...THROUGH CENTRAL AND SOUTHERN MN AND SOUTHERN WI
WITH WIDESPREAD MCS ACTIVITY IN THOSE AREAS. DENSE FOG CONTINUED
NEAR LAKE SUPERIOR AND HAVE ISSUED A DENSE FOG ADVISORY FOR LAND
AND WATER AREAS.
THE BIG QUESTION IS THE EVOLUTION OF THE WIDESPREAD SHOWERS AND
THUNDERSTORMS TO THE SOUTH OF THE AREA. AS EXPECTED WITH THIS TYPE
OF PATTERN...THE MODELS REALLY DO NOT HAVE A HANDLE ON THE CURRENT
PRECIPITATION. THERE ARE A FEW EXCEPTIONS...INCLUDING THE 4 KM WRF
AND THE 06Z HRRR RAPID REFRESH. BOTH HAVE A RELATIVELY DECENT
HANDLE ON THE CURRENT PRECIPITATION TRENDS...AND BOTH BRING THE
PRECIPITATION NORTH AND EASTWARD INTO OUR CWA. HAVE DONE SOME
DRAMATIC MODIFICATIONS TO POPS AND WEATHER FOR TODAY. THE TWO HIGH
RESOLUTION MODELS ACTUALLY LIFT IT INTO THE CWA BUT DECREASE THE
PRECIPITATION GRADUALLY. WILL KEEP THIS TREND GOING. HAVE ALSO
ADDED AREAS OF DRIZZLE AND DENSE FOG NEAR LAKE SUPERIOR...WHICH
WILL LIKELY CONTINUE THROUGHOUT THE DAY IN SOME FORM.
FOR LATER TODAY AND TONIGHT...MOST OF THE MODEL SOLUTIONS DO BRING
A DRAMATIC INCREASE IN PRECIPITATION...AS A FRONTAL BOUNDARY
STRETCHES FROM SW TO NE ACROSS THE AREA. WILL INCREASE POPS LATER
TODAY AND TONIGHT. COULD STILL SEE SOME STRONG TO SEVERE STORMS IF
WE ARE ABLE TO SEE ENOUGH DAYTIME HEATING FOR SURFACE BASED
CONVECTION. THE FAIRLY HIGH CHANCE OF SHOWERS AND THUNDERSTORMS
WILL ALSO CONTINUE ON SUNDAY...AS THE FRONT REMAINS IN THE AREA.
WILL DEFINITELY NEED TO CONTINUE TO MONITOR THE THREAT OF FLOODING
ACROSS THE AREA. PRECIPITABLE WATER VALUES ARE ON THE ORDER OF 1.8
INCHES TODAY INTO SUNDAY...SO THERE IS ABUNDANT AVAILABLE MOISTURE.
TEMPS WILL BE TROUBLESOME TODAY BASED ON CLOUDS AND PCPN TRENDS.
OVERALL WE SHOULD SEE 70S FOR MOST AREAS TODAY AND SOME 80S
SUNDAY. IT WILL BE DRAMATICALLY COOLER NEAR LAKE SUPERIOR WITH
SOME FAIRLY STRONG NORTHEAST WINDS.
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY NIGHT...
UPPER LOW AND CO-LOCATED SFC LOW WILL MOVE FROM SRN MANITOBA AND WRN
ONTARIO TO THE E/NE ACROSS NRN/CENTRAL ONTARIO SUNDAY NIGHT AND
MONDAY MORNING. A TRAILING COLD FRONT WILL SWEEP ACROSS THE UPPER
MIDWEST AND BRING RAIN SHOWERS AND THUNDERSTORMS TO MUCH OF THE
NORTHLAND THROUGH MON MORNING. HIGH PRESSURE IS EXPECTED TO BUILD IN
ACROSS NRN MN LATE MON AFTERNOON AND INTO MONDAY NIGHT. THIS WILL
ALLOW CONDITIONS TO REMAIN QUIET...AT LEAST UNTIL TUE MORNING WHEN
THE NEXT FRONT IS EXPECTED TO LIFT NWD THROUGH THE REGION AND SPREAD
ANOTHER ROUND OF SHOWERS AND STORMS THROUGH WED EVENING. AN AREA OF
LOW PRESSURE WILL DEVELOP OVER S-CENTRAL CANADA...ON THE NWRN FLANK
OF THE SFC TROUGH/WARM FRONT...AND MOVE EWD INTO NRN ONTARIO ON
THURSDAY. THIS LOW PRESSURE WILL DRAW IN SLIGHTLY COOLER AIR FROM
NRN CANADA AND MODIFY LOW LEVEL THERMAL PROFILES ACROSS NRN MN
ENOUGH TO TRIGGER SHOWERS AND STORMS ACROSS THE REGION THROUGH
FRIDAY.
TEMPERATURES MONDAY THROUGH THURSDAY WILL BE WARM WITH HIGHS IN THE
70S AND 80S...AND 60S AROUND THE PERIPHERY OF LAKE SUPERIOR.
OVERNIGHT LOWS WILL BE MILD WITH TEMPS DROPPING INTO THE UPPER 50S
AND 60S.
&&
.AVIATION.../06Z TAF ISSUANCE/
NEXT FEW HOURS A CLUSTER OF THUNDERSTORMS MAY AFFECT KHYR WITH IFR
CIGS AND MVFR VSBYS. OTHERWISE...LAKE EFFECTS ARE PRODUCING
STRATUS OVER MOST OF THE REGION WITH MVFR CIGS...WITH LIFR AT KDLH.
STRATUS HAS LOTS OF HOLES STILL AT KBRD AND KHYR...AND KINL HAS
NOT BEEN AFFECTED AT ALL. THIS STRATUS LAYER SHOULD CONTINUE
OVERNIGHT WITH SOME MVFR FOG ALSO EXPECTED. KDLH TO REMAIN LIFR IN
FOG AND STRATUS WITH THE LIGHT EAST WINDS CONTINUING. WINDS TO
TURN MORE SOUTHERLY SATURDAY IN THE 15Z-18Z TIME RANGE AND EXPECT
CIGS TO IMPROVE DURING THE DAY. SHOWERS AND THUNDERSTORMS ARE
EXPECTED DURING THE AFTERNOON FOR AT LEAST A SHORT TIME...BUT
TIMING AND LOCATION STILL UNCERTAIN SO HAVE LEFT AS VCTS FOR NOW.
&&
.POINT TEMPS/POPS...
DLH 70 57 77 60 / 60 70 60 60
INL 75 62 77 58 / 50 50 60 60
BRD 81 67 82 61 / 70 70 50 50
HYR 83 69 86 63 / 60 70 60 60
ASX 76 61 83 61 / 60 70 60 60
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR MNZ020-021-
037.
WI...DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR WIZ001>004.
LS...DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR LSZ121-
140>148.
SMALL CRAFT ADVISORY FROM 7 AM THIS MORNING TO 10 PM CDT THIS
EVENING FOR LSZ143>146.
&&
$$
SHORT TERM...DAP
LONG TERM....TENTINGER
AVIATION...TENTINGER
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
112 AM CDT SAT JUN 22 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 345 PM CDT FRI JUN 21 2013
ANOTHER ACTIVE SHORT TERM IS EXPECTED...WITH POTENTIAL FOR BOTH
ANOTHER SEVERE WEATHER EVENT AND A SIGNIFICANT FLASH FLOOD EVENT
OVER SRN MN BEING CLOSELY MONITORED TONIGHT.
WARM FRONTAL BOUNDARY AT 3PM STRETCHES FROM ROUGHLY MARSHALL OVER
TOWARD RED WING. VERY UNSTABLE AIRMASS COMBINED WITH A WAVE THAT
CAME OUT OF THE BLACK HILLS THIS MORNING HAS SEVER CLUSTER OF STORMS
OVER SODAK THAT IS RAPIDLY APPROACHING SW MN. THE SYSTEM IS STARTING
TO BOW...WITH HURON REPORTING A WIND GUST OF 87 MPH. HAVE BEEN
LEANING ON THE HRRR HEAVILY ALL DAY TO TRACK THIS SYSTEM ACROSS THE
AREA. EXPECT THESE STORMS TO BASICALLY FOLLOW THE WARM FRONT AND
850-300 THICKNESS LINES TO THE ESE ACROSS SRN MN. TORNADO/LARGE HAIL
TREAT WILL BE HIGHEST ALONG THE SODAK BORDER...WITH THE THREAT
TRANSITIONING OVER TO MORE OF A WIND THREAT AS YOU HEAD EAST. WOULD
NOT BE SURPRISED IF BY 5 OR 6 PM WE ARE COORDINATING WITH THE SPC
FOR A SVR THUNDERSTORM WATCH TO THE EAST OF THE CURRENT TOR WATCH.
FOR TONIGHT THOUGH...THE REAL BIG CONCERN IS THE POTENTIAL FOR A
SIGNIFICANT RAINFALL/FLASH FLOODING EVENT ACROSS SRN MN. THE RAP HAS
THE NOSE OF A PERSISTENT 40-50 KT LLJ COMING UP OUT OF THE PLAINS
AND REMAINING MORE OR LESS STATIONARY INTO SW MN. AS THE HRRR
SHOWS...WITH 3000-5000 J/KG OF MUCAPE REMAINING IN PLACE WITH THE
LLJ...THE PROBABILITY FOR ADDITIONAL TSRA DEVELOPMENT BACK INTO THE
SD/NEB/IA AREA THROUGH THE NIGHT WILL BE HIGH. THIS WILL LEAD TO A
THREAT FOR TRAINING OF STORMS TONIGHT...WITH THE POTENTIAL FOR SOME
RATHER SIGNIFICANT RAINFALL TOTALS IN EXCESS OF 6 INCHES POSSIBLE
FOR TONIGHT. GIVEN THE POTENTIAL...HAVE ISSUED A FLASH FLOOD WATCH
FOR AREAS ALONG AND SOUTH OF AN APPLETON TO CHIPPEWA FALLS
LINE...WITH THE POTENTIAL FOR SEEING MULTIPLE ROUNDS OF STORMS IS
HIGHEST. GIVEN THE SOUTHERN POSITION OF THE WARM FRONT...LESSER
AMOUNTS OF RAINFALL ARE CURRENTLY ANTICIPATED OVER CENTRAL MINNESOTA
INTO NW WISCONSIN.
LIKE TODAY...EXPECT ACTIVITY TO WIND DOWN THROUGH THE MORNING ACROSS
THE MPX AREA...WITH MUCH OF THE LATE MORNING INTO THE EARLY
AFTERNOON REMAINING DRY. THE BIG DIFFERENCE THOUGH ON SATURDAY TO
THE PAST TWO DAYS...IS THE SYNOPTIC COLD/STATIONARY FRONT AND LOW
PRESSURE SYSTEM WILL BE FARTHER EAST. BY THE AFTERNOON...MODELS SHOW
A LEE SIDE LOW DEVELOPING OVER ERN COLORADO...WITH A STATIONARY
FRONT/PRESSURE TROUGH EXTENDING TO THE NORTHEAST TOWARD WRN MN. WITH
THE SYNOPTIC FEATURES FARTHER EAST TOMORROW...THIS SHOULD INCREASE
THE CHANCES FOR THUNDERSTORMS DEVELOPING IN THE AFTERNOON ACROSS THE
MPX AREA...WHICH WILL LEAD TO A HIGHER PROBABILITY FOR SEEING
TORNADOES OR HAIL DURING THE AFTERNOON...BEFORE ANOTHER POTENTIAL
ROUND OF STORMS GOING INTO SATURDAY NIGHT.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 345 PM CDT FRI JUN 21 2013
NO SIGNIFICANT CHANGES FROM THE PREVIOUS FORECAST...WITH SEVERE AND
HYDRO CONCERNS CONTINUING THROUGH EARLY NEXT WEEK. THE UPPER LEVEL
LOW WILL LINGER JUST TO THE WEST...WITH THE SURFACE TROUGH INCHING
EVER CLOSER TO WESTERN MINNESOTA BY THE WEEKEND...AND THE FRONTAL
BOUNDARY STALLED OUT EAST/WEST ACROSS THE FORECAST AREA ONLY TO
OSCILLATE NORTH/SOUTH WITH EACH CONVECTIVE OUTFLOW BOUNDARY. THE
TROPICAL AIRMASS WILL REMAIN IN PLACE THROUGH EARLY NEXT WEEK...WITH
PWAT VALUES IN THE 1.75 TO 2.00 INCH RANGE. SREF 21.09 MLCAPE PLUMES
CONTINUE TO SHOW 2500 TO 4000J/KG DURING THE AFTERNOON...AND THIS
SEEMS REASONABLE CONSIDERING WHAT IS CURRENTLY GOING ON ACROSS
SOUTHWEST MINNESOTA. DEEP LAYER SHEAR WILL ONLY BE IN THE 25KT
RANGE...BUT THE SEVERE WEATHER REMAINS A CONCERN SINCE THE STORMS
MAY BE ABLE TO MODIFY THEIR OWN ENVIRONMENT AS IS THE CASE THIS
AFTERNOON ACROSS EASTERN SOUTH DAKOTA. AS THE SURFACE TROUGH SLOWLY
PROGRESSES EASTWARD...THE POTENTIAL FOR AFTERNOON CONVECTION WILL
INCREASE AS WELL. THEREFORE THE MISSISSIPPI RIVER VALLEY MAY
TRANSITION FROM A PURELY NOCTURNAL EVENT AS WAS THE CASE LAST
NIGHT...TO MORE OF A AFTERNOON AND EVENING FOCUS. FORECAST MODELS
CONTINUE TO SHOW A SHORTWAVE MOVING ACROSS NORTHERN MINNESOTA
SATURDAY NIGHT...SO IF STORMS DO NOT DEVELOP TOMORROW AFTERNOON THEY
WILL CERTAINLY FORM AHEAD OF THAT WAVE. ANOTHER WAVE FOLLOWS FOR
SUNDAY EVENING...SO COULD SEE SOME QUICK REDEVELOPMENT DURING THE
DAY ON SUNDAY.
LOOKING AHEAD...BOTH THE GFS AND ECMWF TRANSITION TO A MORE ZONAL
PATTERN WITH THE H250 JET STRADDLING THE INTERNATIONAL BORDER...AND
CONTINUED CHANCES FOR POPS THROUGH THE MIDDLE OF THE WEEK. THE UPPER
LEVEL RIDGE TRIES TO BUILD ACROSS THE ROCKIES BY LATE NEXT
WEEK...BUT CONFIDENCE IS LOW IN THE DEVELOPMENT OF THIS FEATURE
GIVEN THE CONTINUED DELAYED ONSET WITH EACH MODEL RUN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1249 AM CDT SAT JUN 22 2013
ANOTHER POTENTIALLY ACTIVE 24 HOUR PERIOD EXPECTED...MAINLY IN THE
FIRST 6 HOURS AND THEN IN THE LAST 6 HOURS. CDFNT WOBBLING OVER
THE IA/MN BORDER WILL SLOWLY LIFT N DURG THIS TAF PERIOD.
RAIN/TSTMS ALONG IT OVER MAINLY FAR SRN MN INTO SW WI WILL SLOWLY
SHIFT N THIS MRNG...RESULTING IN DEGRADED CONDS FOR KRWF-KMSP-
KEAU-KRNH. AM THINKING KAXN-KSTC SHOULD STAY OUT OF THE ACTION
THIS MRNG. ONCE THE PRECIP ENDS...WHICH SHOULD BE BY 12Z THIS
MRNG...WILL HAVE A REPRIEVE FROM THE PRECIP AND THERE MAY EVEN BE
A FEW BREAKS IN THE OVC. ONCE THE ATMOS RELOADS ITS
INSTABILITY...LIFT FROM THE NWW-MOVNIG CDFNT AND A CONTINUED MOIST
ATMOS WILL ALLOW FOR RE-DEVELOPMENT OF CONVECTION LATE THIS AFTN
THRU THIS EVE. STILL SOME TIMING ISSUES BUT HAVE GENERALLY
HIGHLIGHTED THE BEST TIMING FOR EACH TAF SITE BASED ON GRIDDED
FORECASTS AND RAP/HRRR MODELS. THESE TEMPO GROUPS AT THE END OF
THE TAFS MAY WELL NEED TO BE ADJUSTED BUT FELT CONFIDENT ENOUGH
ATTM TO AT LEAST HIGHLIGHT THE LIKELY CHC OF TSTMS LATER TDA.
KMSP...GENERALLY LIGHT SHOWERS WITH A SOME IC/CC/CG LIGHTNING OVER
THE FIRST FEW HRS OF THE 06Z TAF THEN PRECIP ACTIVITY WILL WANE
GOING INTO DAYBREAK. PRECIPITATION WILL RESUME LATER THIS EVENING
AND POTENTIALLY INTO THE OVERNIGHT HOURS. STILL SOME TIMING ISSUES
AS TO WHEN BUT HAVE HIGHLIGHTED THE BEST TIMING GIVEN CURRENT
SHORT-TERM MODEL RUNS AND GRIDDED FCSTS. STILL ALSO THE POTENTIAL
FOR WINDS IN EXCESS OF 35 KT LET ALONE THE SLGT RISK FOR SEVERE
TSTMS THIS EVENING AND TNGT.
/OUTLOOK FOR KMSP/
SUN...TSRA LIKELY. VFR OUTSIDE OF TSRA. WINDS SSW 10-15 KTS.
MON...CHC TSRA. VFR OUTSIDE OF TSRA. WINDS S 5-10 KTS.
TUE...CHC TSRA. VFR OUTSIDE OF TSRA. WINDS SSE 10-15 KTS.
&&
.HYDROLOGY...
ISSUED AT 345 PM CDT FRI JUN 21 2013
AS ALLUDED TO EARLIER PWATS WILL BE IN THE 90TH PERCENTILE
THOUGH EARLY NEXT WEEK. THE AREA IS INCREASINGLY VULNERABLE TO BOTH
FLASH FLOODING...AND RIVER FLOODING GIVEN THE WIDESPREAD RAINFALL
AMOUNTS OF 2-4 INCHES FALLING LAST NIGHT. THE EAST/WEST FRONTAL
BOUNDARY SUPPORTS TRAINING THUNDERSTORMS...AND THE H925 MOISTURE
TRANSPORT SURGES NORTHWARD OVERNIGHT AS THE LOW LEVEL JET DECOUPLES
FROM THE BOUNDARY LAYER. CONTINGENCY FORECAST BASED OFF DIFFERENT
QPF SCENARIOS SHOW THE POTENTIAL FOR SIGIFICANT FLOODING BY EARLY
NEXT WEEK ALONG THE QUICKER RESPONSE RIVERS...AND EVENTUALLY THE
LARGER MAIN STEMS OF THE MINNESOTA AND MISSISSIPPI RIVER.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR MNZ041>045-047>070-
073>078-082>085-091>093.
WI...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR WIZ014>016-023>028.
&&
$$
SHORT TERM...MPG
LONG TERM...JRB
AVIATION...JPC
HYDROLOGY...JRB
AREA FORECAST DISCUSSION
NWS JACKSON MS
1217 PM CDT SAT JUN 22 2013
.UPDATE...
WILL UPDATE TO INCREASE POPS A BIT FOR THE AFTERNOON...BUT STILL
EXPECT COVERAGE TO REMAIN FAIRLY ISOLATED. A FEW SHOWERS/THUNDERSHOWERS
HAVE DEVELOPED ALONG/WEST OF THE I-55 CORRIDOR IN REGION OF SUBTLE
LOW LEVEL MOISTURE CONVERGENCE INDUCED BY WEAK UPPER LEVEL DIVERGENCE
ALONG THE MS RIVER. MORNING RUNS OF THE HRRR HAD SEEMED A LITTLE
OVERDONE BUT LOOK PRETTY GOOD RIGHT NOW. /EC/
&&
.PREV DISCUSSION... /ISSUED 1059 AM CDT SAT JUN 22 2013/
UPDATE...
THE FORECAST IS ON TRACK AND ONLY MINOR ADJUSTMENTS WERE MADE TO
TEMPERATURES AND AFTERNOON WEATHER. DID NOT ADJUST LOW POPS...BUT
VARIOUS HIGH-RES GUIDANCE SUGGEST ISOLATED SHOWERS/THUNDERSHOWERS ARE
A GOOD POSSIBILITY OVER WESTERN/SOUTHERN PORTIONS OF THE FORECAST
AREA AND HAVE ADDED EXPLICIT MENTION. /EC/
&&
.AVIATION...
VFR CONDS TO PERSIST THRU THE REMAINDER OF THE DAY. ISOLD SHRA MAY
DEVELOP ACROSS SRN MS THRU THE AFTN BEFORE QUIET CONDS RETURN THIS
EVE. MVFR/IFR CIG AND VSBY MAY DEVELOP AT HBG/PIB TOMORROW MORNING
10-14Z. SFC WINDS WL REMAIN LGT AND ELY/SELY OVR THE NEXT 24 HRS.
/BK/
PREV DISCUSSION... /ISSUED 334 AM CDT SAT JUN 22 2013/
SHORT TERM...TODAY THROUGH SUNDAY NIGHT...WEAK E/SELY ANTICYCLONIC
FLOW AT LOWER LEVELS ALONG WITH BACKING FLOW ALOFT WILL KEEP
CONVECTION GENERALLY QUIET TODAY. ONE OR TWO VERY ISOLATED CELLS
MAY POP UP DURING THE LATE AFTERNOON AND EARLY EVENING BUT
CONDITIONS WILL GENERALLY REMAIN DRY ACROSS THE REGION. RAIN CHANCES
WILL INCREASE SOMEWHAT FOR SUNDAY AFTERNOON AND EVENING...MAINLY IN
THE SOUTH. WEAK LOW LEVEL CONVERGENCE AND THE DEVELOPMENT OF FLAT
UPPER TROUGHING SUNDAY WILL PRODUCE ISOLATED TO SCATTERED SHOWERS
AND THUNDERSTORMS GENERALLY I-20 SWD IN THE AFTERNOON AND EVENING
SUNDAY.
OTHER THAN A FEW SMALL TWEAKS MAV MOS GUIDANCE WAS FOLLOWED...
TEMPERATURES PRIMARILY CONTINUING CLOSE TO SEASONAL NORMS.
LONG TERM...MONDAY INTO NEXT WEEKEND...THIS PORTION OF THE FORECAST
LOOKING RATHER TYPICAL...ALTHOUGH PERHAPS A BIT ON THE DRYISH
SIDE...THROUGH AT LEAST NEXT THURSDAY. THROUGH THE WEEK THE CENTER
OF SUPPRESSIVE SUBTROPICAL RIDGING ALOFT WILL SHIFT FARTHER AND
FARTHER WEST OF OUR REGION ALTHOUGH TRUE TROUGHING SHOULD NOT DIG
DOWN THIS WAY UNTIL AROUND FRIDAY. FLOW AT THE SURFACE WILL
GENERALLY BE WEAK AND SOUTHERLY...BUT EXHIBITING SOME ANTICYCLONIC
TENDENCIES DUE TO AT LEAST WEAK SUBSIDENCE IN THE VICINITY FOR MUCH
OF THE WEEK. BECAUSE OF THIS LATTER FACT...AND THE IDEA THAT SURFACE
COMBINATIONS OF HEAT AND HUMIDITY WILL NOT BE OVERLY HIGH...EXPECT
AFTERNOON CONVECTION TO BE GENERALLY ISOLATED AT BEST THROUGH THE
WORK WEEK. EXCEPTIONS TO THIS COULD COME IN SOUTHERN ZONES BY
THURSDAY AND FRIDAY WHEN ACTIVE SEABREEZE-RELATED BOUNDARIES HAVE A
BETTER CHANCE OF GETTING SUFFICIENTLY NORTH FROM THE COAST.
BY FRIDAY AND DEFINITELY INTO NEXT WEEKEND NUMERICAL MODEL CONSENSUS
IS FAIRLY GOOD THAT A SOMEWHAT SIGNIFICANT SUMMER UPPER LEVEL TROUGH
WILL DIG DOWN INTO THE EASTERN HALF OF THE CONUS. THIS SHOULD DRIVE
A COLD FRONT SOUTH INTO OUR REGION BY SATURDAY...WITH THIS BOUNDARY
REACTING WITH MOISTURE AND INSTABILITY TO INCREASE THUNDERSTORM
PRODUCTION A GOOD DEAL. AT THIS POINT IT IS HARD TO SAY WHETHER THIS
TROUGH WILL BE A BIG ENOUGH DEAL TO TRULY PUSH THE FRONT SOUTH OF
OUR REGION...WHICH IS SOMETHING HARD TO DO AT THE START OF JULY.
AS FOR TEMPERATURES...GFS-BASED MEX GUIDANCE LOOKED GOOD ADVERTISING
TEMPS PERHAPS SLIGHTLY ABOVE AVERAGE FOR HIGHS BUT NEAR AVERAGE FOR
LOWS. I MADE ONLY A FEW SLIGHT TWEAKS THROUGH THE PERIOD BASED ON
TRENDS THUS FAR THIS SUMMER. OF COURSE SOME DEGREE OF COOL DOWN
ANTICIPATED BY NEXT WEEKEND WITH THE FRONT COMING IN...BUT UNTIL
THEN HEAT SHOULD NOT BE OPPRESSIVE ENOUGH TO WARRANT HEAT
ADVISORIES.
FINALLY...MONDAY THROUGH AT LEAST THURSDAY THERE ARE NO SIGNALS FOR
MUCH ROBUST TSTORM ACTIVITY. STRONGER STORMS POSSIBLE WITH THE FRONT
AT THE END OF THE WEEK BUT IT IS STILL WAY TOO EARLY TO ADVERTISE
THAT IN THE HWO. /BB/
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1149 PM CDT FRI JUN 21 2013
.UPDATE...
ISSUED AT 933 PM CDT FRI JUN 21 2013
SCANT CONVECTION THAT DOTTED OUR S IL COUNTIES EARLY THIS EVENING
HAS DISSIPATED...AND AM EXTREMELY HARD-PRESSED TO DISCERN ANY MECHANISM
FOR REDEVELOPMENT OVERNIGHT. STRONGEST 850MB WAA WILL BE FOCUSED
WELL TO OUR N THROUGHOUT THE NIGHT...AND THE MID LEVEL WAA THAT
WAS RESPONSIBLE FOR LAST NIGHTS CONVECTION IS MUCH...MUCH WEAKER
OVER OUR AREA THAN IT WAS LAST NIGHT. SO...WILL GO WITH A DRY
FORECAST FOR REMAINDER OF THE NIGHT WITH SOME OCCASIONAL MID AND
HIGH LEVEL CLOUDINESS. TEMPERATURE TRENDS STILL LOOKING GOOD.
ZONES WILL BE OUT IN A SECOND.
TRUETT
&&
.SHORT TERM...(THROUGH LATE TONIGHT)
ISSUED AT 323 PM CDT FRI JUN 21 2013
THE MAIN SHORT-TERM CONCERN IS THE MCS GENERATED OUTFLOW BOUNDARY
CURRENTLY DROPPING S/SEWD THROUGH CENTRAL IL. WHILE THE MCS
ITSELF IS MOVING SEWD...THE RUC 0-3 KM AND 0-6 KM SHEAR VECTORS
SUGGEST THAT AS LONG AS THIS BOUNDARY MAINTAINS ITS IDENTITY IT
SHOULD CONTINUE TO DROP S/SEWD AND AT LEAST IMPACT AREAS EAST OF
THE MS RIVER LATE THIS AFTERNOON INTO EARLY THIS EVENING. THE AIR
MASS AHEAD OF THIS BOUNDARY IS WEAKLY CAPPED WITH SBCAPE INCREASING
FROM 2000 J/KG IN CENTRAL IL TO NEAR 4000 J/KG ALONG THE RIVER.
THIS COMBINATION OF INSTABILITY/CAPPING AND CONVERGENCE WITH THE
BOUNDARY SUPPORTS A GREATER CHANCE OF MORE ORGANIZED CONVECTION
ACROSS SOUTH CENTRAL IL WHERE SCATTERED THUNDERSTORMS ARE POSSIBLE.
ELSEWHERE THROUGH SUNSET ANY THREAT OF SHOWERS/THUNDERSTORMS WILL
BE ISOLATED PULSE TYPE ACTIVITY ASSOCIATED WITH DIURNAL HEATING. I
THINK THERE WILL THEN BE A LULL FROM SAY AROUND 02-03Z TIL 08Z OR
SO...THEN ANOTHER CHANCE OF SHOWERS AND THUNDERSTORMS...PRIMARILY
ACROSS ERN MO INTO SW/SC IL... ASSOCIATED WITH LOW-MID LEVEL WAA
VIA THE SWLY LLJ AND STEEP MID LEVEL LAPSE RATES. OVERNIGHT LOWS
WILL BE QUITE MILD AND ABOVE SEASONABLE NORMS.
GLASS
.LONG TERM...(SATURDAY THROUGH NEXT FRIDAY)
ISSUED AT 323 PM CDT FRI JUN 21 2013
(SATURDAY THROUGH MONDAY)
BROKEN RECORD FOR WEATHER PATTERN AS WE REMAIN IN WARM SECTOR ON
SATURDAY WITH SOME WEAK INSTABILITY AND PLENTY OF MOISTURE. SO ANY
OLD OUTFLOW BOUNDARY...ETC COULD TRIGGER ISOLATED THUNDERSTORM
DEVELOPMENT...SO KEPT SLIGHT CHANCE POPS FOR SATURDAY AFTERNOON.
OTHERWISE...HIGHS WILL BE IN THE UPPER 80S TO LOW 90S...POSSIBLY IN
THE MID 90S IN THE STL METRO AREA. LOWS SATURDAY NIGHT WILL BE IN
THE LOW 70S.
UPPER RIDGE BUILDS IN A BIT STRONGER ON SUNDAY...SO THUNDERSTORM
CHANCES DIMINISH. BUT HOT AND HUMID CONDITIONS TO PERSIST WITH HIGHS
IN THE UPPER 80S TO LOW 90S. ON SUNDAY NIGHT AND MONDAY...UPPER
RIDGE BEGINS TO WEAKEN AGAIN AS NEXT WEATHER SYSTEM APPROACHES THE
REGION. MCS EXPECTED TO DEVELOP ALONG BOUNDARY OVER IOWA...WITH
SOUTHERN FRINGES SLIDING THROUGH NORTHERN MO/WEST CENTRAL IL ON
MONDAY. LOWS SUNDAY NIGHT WILL BE IN THE LOW TO MID 70S WITH HIGHS
ON MONDAY IN THE UPPER 80S TO LOW 90S.
(MONDAY NIGHT THROUGH FRIDAY)
EXTENDED MODELS CONTINUE TO SLOW DOWN PASSAGE OF THIS COLD
FRONT...SO HOT AND HUMID CONDITIONS TO PERSIST THROUGH THURSDAY WITH
HIGHS EACH DAY IN THE UPPER 80S TO MID 90S. BY WEDNESDAY
NIGHT...COLD FRONT MOVES CLOSER TO AREA WITH CHANCES OF SHOWERS AND
THUNDERSTORMS FOR PORTIONS OF THE AREA WEDNESDAY NIGHT AND THURSDAY.
CONFIDENCE ON TIMING OF FRONTAL PASSAGE LOW...SO FOR NOW HAVE SILENT
SLIGHT CHANCE POPS IN FOR AREA THURSDAY NIGHT AND PORTIONS OF THE
AREA FRIDAY UNTIL FRONT FINALLY MOVES THROUGH. BY FRIDAY HIGHS WILL
BE IN THE MID TO UPPER 80S.
BYRD
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1140 PM CDT FRI JUN 21 2013
NOT MUCH CHANGE FROM PREVIOUS TAF PACKAGE. MIDLEVEL ANTICYCLONE
REMAINS OVERHEAD STEERING ANY ORGANIZED CONVECTION WELL AWAY FROM
THE CWFA. LATEST NAM/GFS DOES TRY AND PAINT OUT SOME LIGHT
PRECIPITATION OVERNIGHT TONIGHT. HOWEVER...MODELS DID NOT SEEM TO
INITIALIZE CURRENT CONVECTION WELL. GIVEN THAT NOTE AND POSITION
BENEATH SYNOPTIC RIDGE...HAVE CONTINUED TO LEAVE OUT ANY MENTION
OF TS/SHRA. SCT HIGH-LEVEL CLOUDINESS WILL GIVE WAY TO MORE
DIURNAL CU WITH VFR BASES. AS FOR WINDS...SOUTHERLY WINDS WILL
CONTINUE THROUGH THE VALID TAF PERIOD AND PICK UP JUST A BIT
DURING THE DAY TOMORROW AROUND 10 KTS. BUFKIT SOUNDINGS DO NOT
SHOW MUCH IN THE WAY OF WINDS TO MIX DOWN TO SFC AT TOP OF
BOUNDARY LAYER UNLIKE THIS AFTERNOON...SO DO NOT HAVE ANY GUSTS MENTIONED.
SPECIFICS FOR KSTL...
NOT MUCH CHANGE FROM PREVIOUS TAF PACKAGE. MIDLEVEL ANTICYCLONE
REMAINS OVERHEAD STEERING ANY ORGANIZED CONVECTION WELL AWAY FROM
LAMBERT FIELD. LATEST NAM/GFS DOES TRY AND PAINT OUT SOME LIGHT
PRECIPITATION OVERNIGHT TONIGHT. HOWEVER...MODELS DID NOT SEEM TO
INITIALIZE CURRENT CONVECTION WELL. GIVEN THAT NOTE AND POSITION
BENEATH SYNOPTIC RIDGE...HAVE CONTINUED TO LEAVE OUT ANY MENTION
OF TS/SHRA. SCT HIGH-LEVEL CLOUDINESS WILL GIVE WAY TO MORE
DIURNAL CU WITH VFR BASES DURING THE DAY ON SATURDAY. AS FOR
WINDS...SOUTHERLY FLOW WILL CONTINUE THROUGH THE VALID TAF PERIOD
AND PICK UP JUST A BIT DURING THE DAY TOMORROW AROUND 10 KTS.
BUFKIT SOUNDINGS DO NOT SHOW MUCH IN THE WAY OF WINDS TO MIX DOWN
TO SFC AT TOP OF BOUNDARY LAYER UNLIKE THIS AFTERNOON...SO DID NOT
DENOTE ANY GUSTS.
GOSSELIN
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
250 PM MDT Sat Jun 22 2013
.DISCUSSION...
Tonight through Monday...Upper trof presently over the state.
Associated cold pool aloft contributing to the instability and
the resulting scattered thunderstorms. Thunderstorm activity has
decreased the past couple of hours but HRRR analysis and the
latest RUC indicate isolated storms remain a possibility during
the evening hours. The upper trof moves east and away from the
area Sunday. Rising heights will bring drier conditions with the
exception of the area along the international boundary. Cyclonic
flow from the departing upper low over central Saskatchewan will
lead to an area of convergence along the border and the
possibility of isolated convection during the afternoon. By
Monday, an increasing southwest flow aloft will bring another round
of moisture and instability to the area with scattered
thunderstorms developing again during the afternoon. Temperatures
will climb to near or slightly above seasonal averages to start
the week. Emanuel
Monday night through Saturday...Expect two different weather
patterns during the period. Early in the week models indicate a
moist southwest flow aloft. A weather disturbance aloft is
expected to move northeast through the area Monday night and
Tuesday with the GFS model faster with this feature than the ECMWF
and GEM models. Models differ with details of their precipitation
forecasts so have not fiddled much with the inherited forecast of
a chance of showers/thunderstorms. At this time it does not look
like thunderstorms will be severe. Then later in the week models
are on the same page in developing a strong upper ridge over the
western U.S. with forecast temperatures rising to well above
normal. Will continue to forecast high temperatures above most
forecast guidance from the models. Thus expect highs in the upper
80s to lower 90s for the lower elevations Friday and Saturday. The
intensifying upper ridge should also result in dry weather
Wednesday night through Friday. Friday night through Saturday
could see an increase in moisture mainly over the northern zones.
Will follow the lead of the Glasgow weather office and mention a
slight chance of showers/thunderstorms in the north. Blank
&&
.AVIATION...
Updated 1720Z.
An unstable airmass remains over the area today. The greatest
instability will be over southwest and central Montana, along and
south of a KHLN to KLWT line. Some of the heavier showers and storms
will produce gusty winds...small hail...and could result in brief
MVFR conditions. Expect most of the showers and storms to diminish
this evening with VFR conditions prevailing through noon Sunday.
Winds will remain light today except near showers and storms.
Langlieb
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 45 75 51 78 / 20 10 10 30
CTB 44 73 49 73 / 10 20 20 40
HLN 45 77 52 78 / 20 10 10 30
BZN 40 76 46 80 / 20 10 10 30
WEY 31 68 36 70 / 20 10 10 30
DLN 39 74 47 74 / 20 10 10 30
HVR 48 77 53 81 / 20 20 10 30
LWT 43 72 48 78 / 40 10 10 30
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...
LONG TERM...
AVIATION...
weather.gov/greatfalls
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
1120 AM MDT Sat Jun 22 2013
UPDATED AVIATION SECTION
.DISCUSSION...
Update forthcoming. Upper trof over the area today will bring
scattered showers and thunderstorms. Radar continues to indicate a
line of showers along the Belts that is very slowly moving to the
north. HRRR analysis indicates this line will become an area of
scattered showers later this afternoon. Have made minor adjustments
to the pop grids. Temperatures look good. Emanuel
&&
.AVIATION...
Updated 1720Z.
An unstable airmass remains over the area today. The greatest
instability will be over southwest and central Montana, along and
south of a KHLN to KLWT line. Some of the heavier showers and storms
will produce gusty winds...small hail...and could result in brief
MVFR conditions. Expect most of the showers and storms to diminish
this evening with VFR conditions prevailing through noon Sunday.
Winds will remain light today except near showers and storms.
Langlieb
&&
.PREV DISCUSSION...Issued 416 AM MDT Sat Jun 22 2013
Today through Monday...Another cool and unsettled weather day is
expected across much of Southwest and Central MT today. With the
main upper level low expected to move eastward across southern
Idaho today...combined with some fairly cold air aloft...another
day of small hail will be possible across portions of Central MT
from any of the stronger storms. Severe storms are not
expected...as the instability is not expected to be very high.
Additionally...light snow will fall this morning across the higher
elevations of Southwest MT...mainly above 7000 feet. New snow
accumulations should generally be less than inch. Afternoon
temperatures will remain a bit below normal...with highs mostly in
the 60s at lower elevations. For Sunday...expect the area to
mainly be in-between storm system...with the flow aloft becoming a
bit more southwesterly. This will result in warmer air returning
to the region...and the best chance for any precipitation to occur
will be over the front range of the Rockies and near the
US/Canadian border. For Monday...the next upper level trof begins
to approach the region. However...forecast models differ on how
far east the trof will be by late Monday afternoon.
Therefore...have continued the slight chance for thunderstorms
east of Great Falls...with higher chances west of Great Falls.
Afternoon temperatures will be on the warm side...especially east
of Great Falls. Brusda
Monday night through Saturday...Expect two different weather
patterns during the period. Early in the week models indicate a
moist southwest flow aloft. A weather disturbance aloft is expected
to move northeast through the area Monday night and Tuesday with the
GFS model faster with this feature than the ECMWF and GEM models.
Models differ with details of their precipitation forecasts so have
not fiddled much with the inherited forecast of a chance of
showers/thunderstorms. At this time it does not look like
thunderstorms will be severe. Then later in the week models are on
the same page in developing a strong upper ridge over the western
U.S. with forecast temperatures rising to well above normal. Will
continue to forecast high temperatures above most forecast guidance
from the models. Thus expect highs in the upper 80s to lower 90s for
the lower elevations Friday and Saturday. The intensifying
upper ridge should also result in dry weather Wednesday night
through Friday. Friday night through Saturday could see an increase
in moisture mainly over the northern zones. Will follow the lead of
the Glasgow weather office and mention a slight chance of
showers/thunderstorms in the north. Blank
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 68 44 78 50 / 50 20 10 10
CTB 67 44 75 48 / 20 10 20 10
HLN 67 45 79 51 / 60 20 10 10
BZN 67 40 80 45 / 80 20 10 10
WEY 59 31 67 35 / 70 20 10 10
DLN 65 39 75 46 / 40 20 10 10
HVR 72 47 79 52 / 20 20 20 10
LWT 62 43 74 47 / 80 30 10 10
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
weather.gov/greatfalls
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
10 AM MDT Sat Jun 22 2013
.DISCUSSION...
Update forthcoming. Upper trof over the area today will bring
scattered showers and thunderstorms. Radar continues to indicate a
line of showers along the Belts that is very slowly moving to the
north. HRRR analysis indicates this line will become an area of
scattered showers later this afternoon. Have made minor adjustments
to the pop grids. Temperatures look good. Emanuel
&&
.AVIATION...
Updated 1130Z.
An upper trough will move over the area today and bring occasional
showers and a few thunderstorms to central and southwest Montana.
Towards the Canadian border expect just a few showers and isolated
thunderstorms. With the showers and thunderstorms expect local MVFR
ceilings and possibly visibilities. Also early this morning there
will be local IFR ceilings/visibilities in fog over central Montana.
Do not expect any taf sites to be affected by fog except possibly
KLWT. Other than local lower conditions with fog and thunderstorms
expect VFR conditions today. With the thunderstorms there will also
be the threat of small hail and gusty winds to possibly as high as
35 knots. Other than gusty winds with some of the thunderstorms
winds should be generally light through the period and confidence in
forecast winds is low to moderate. Showers and thunderstorms will
diminish this evening. Blank
&&
.PREV DISCUSSION...Issued 416 AM MDT Sat Jun 22 2013
Today through Monday...Another cool and unsettled weather day is
expected across much of Southwest and Central MT today. With the
main upper level low expected to move eastward across southern
Idaho today...combined with some fairly cold air aloft...another
day of small hail will be possible across portions of Central MT
from any of the stronger storms. Severe storms are not
expected...as the instability is not expected to be very high.
Additionally...light snow will fall this morning across the higher
elevations of Southwest MT...mainly above 7000 feet. New snow
accumulations should generally be less than inch. Afternoon
temperatures will remain a bit below normal...with highs mostly in
the 60s at lower elevations. For Sunday...expect the area to
mainly be in-between storm system...with the flow aloft becoming a
bit more southwesterly. This will result in warmer air returning
to the region...and the best chance for any precipitation to occur
will be over the front range of the Rockies and near the
US/Canadian border. For Monday...the next upper level trof begins
to approach the region. However...forecast models differ on how
far east the trof will be by late Monday afternoon.
Therefore...have continued the slight chance for thunderstorms
east of Great Falls...with higher chances west of Great Falls.
Afternoon temperatures will be on the warm side...especially east
of Great Falls. Brusda
Monday night through Saturday...Expect two different weather
patterns during the period. Early in the week models indicate a
moist southwest flow aloft. A weather disturbance aloft is expected
to move northeast through the area Monday night and Tuesday with the
GFS model faster with this feature than the ECMWF and GEM models.
Models differ with details of their precipitation forecasts so have
not fiddled much with the inherited forecast of a chance of
showers/thunderstorms. At this time it does not look like
thunderstorms will be severe. Then later in the week models are on
the same page in developing a strong upper ridge over the western
U.S. with forecast temperatures rising to well above normal. Will
continue to forecast high temperatures above most forecast guidance
from the models. Thus expect highs in the upper 80s to lower 90s for
the lower elevations Friday and Saturday. The intensifying
upper ridge should also result in dry weather Wednesday night
through Friday. Friday night through Saturday could see an increase
in moisture mainly over the northern zones. Will follow the lead of
the Glasgow weather office and mention a slight chance of
showers/thunderstorms in the north. Blank
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 68 44 78 50 / 50 20 10 10
CTB 67 44 75 48 / 20 10 20 10
HLN 67 45 79 51 / 60 20 10 10
BZN 67 40 80 45 / 80 20 10 10
WEY 59 31 67 35 / 70 20 10 10
DLN 65 39 75 46 / 40 20 10 10
HVR 72 47 79 52 / 20 20 20 10
LWT 62 43 74 47 / 80 30 10 10
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
weather.gov/greatfalls
AREA FORECAST DISCUSSION
NWS BILLINGS MT
947 AM MDT SAT JUN 22 2013
.UPDATE...
SCATTERED TO ISOLATED SHOWERS AND THUNDERSTORMS ARE CONTINUING
FROM BILLINGS EASTWARD THIS MORNING AS A JET MAX IS DRIVING THIS
PRECIPITATION. UPPER TROUGH OVER WESTERN MONTANA THIS MORNING IS
PUSHING SLOWLY EASTWARD AND WILL MOVE ACROSS SC/SE MT THIS
AFTERNOON. ONLY MAJOR ADJUSTMENT TO THE CURRENT FORECAST WAS TO
ADD A CHANCE OF SEVERE THUNDERSTORMS FROM SHERIDAN EAST THROUGH
BROADUS TO EKALAKA FROM 21Z AFTERNOON THROUGH 03Z THIS EVENING.
CONVECTIVE PARAMETERS ARE HIGHLIGHTING THIS AREA FOR THE POTENTIAL
OF LARGE HAIL AND STRONG WINDS. THE UPPER TROUGH WILL BRING IN
STRONG Q VECTOR FORCING ALONG WITH JET DYNAMICS. THE ONLY DRAW
BACK ON THE SEVERE POTENTIAL THIS AFTERNOON/EVENING WILL BE THE
AMOUNT OF SURFACE HEATING THAT WILL TAKE PLACE TODAY. CURRENTLY
LOW LEVEL STRATUS HAS BEEN OVER THIS AREA BUT DUE EXPECT SOME
BREAKS IN CLOUD COVERE THIS AFTERNOON FOR THE BOUNDARY LAYER TO
DESTABILIZE AND STORMS TAPING INTO LOW LEVEL DEW POINTS IN THE
LOW TO MID 50S. NO CHANGES MADE TO HIGH TEMPERATURES FOR TODAY.
RICHMOND
&&
.SHORT TERM...VALID FOR TDY AND SUN...
WIDESPREAD SHOWERS AND STORMS ARE STILL EXPECTED ACROSS THE REGION
THIS AFTERNOON AND EVENING AS THE 500-HPA LOW NEAR BOISE AT 09 UTC
OPENS UP AND SWINGS ACROSS MT. LOCALLY HEAVY RAINFALL IS LIKELY.
FIRST OF ALL...WE WILL INCLUDE SOME PATCHY FOG IN THE FORECAST FOR
PLACES LIKE BAKER AND MILES CITY UNTIL 15 UTC. LOW TEMPERATURE-DEW
POINT SPREADS AS OF 09 UTC AND HRRR FORECASTS BOTH SUPPORT THAT.
TODAY...THE SCATTERED STORMS WHICH HAVE BEEN DEVELOPING OVER SOUTH
CENTRAL MT OVERNIGHT SHOULD LARGELY EXIT THE AREA BY 12 UTC AS THE
RIGHT ENTRANCE REGION OF THE 75+ KT 300-HPA JET STREAK WHICH SEEMS
RESPONSIBLE FOR THIS ACTIVITY HEADS NORTHEAST. MEANWHILE...FORCING
TIED TO THE 500-HPA TROUGH MAY BE A BIT DELAYED WHEN COMPARED WITH
EARLIER EXPECTATIONS. MOST 00 UTC GUIDANCE PICKED UP ON A BIT OF A
SLOW-DOWN WITH THIS SYSTEM...AND THAT LOOKS LIKE A GOOD SIMULATION
SINCE WE STILL HAVE A CLOSED LOW INSTEAD OF AN OPEN WAVE ACROSS ID
EARLY THIS MORNING. BASED ON THIS...WE DECIDED TO ADVERTISE MAINLY
CHANCE POPS ACROSS MUCH OF THE AREA FROM 12 TO 18 UTC...EXCEPT OUT
AROUND LIVINGSTON WHERE FORCING MAY ARRIVE BY LATE MORNING. THE 00
UTC MULTI-MODEL CONSENSUS STILL SUPPORTS CATEGORICAL POPS FOR MOST
OF THE AREA THIS AFTERNOON WHEN STRONGER VERTICAL MOTION SHOWS UP.
PRECIPITABLE WATER VALUES OF 0.75 INCHES OR MORE CERTAINLY SUGGEST
LOCALLY HEAVY RAINFALL IS LIKELY. WHILE MID-LEVEL LAPSE RATES WILL
BE STEEP ENOUGH TO SUPPORT SOME THUNDER...SEVERE RISK WILL BE KEPT
IN CHECK BY A RELATIVELY COOL BOUNDARY LAYER AND RESULTANT LACK OF
CAPE. WE WILL BE WATCHING BURN SCAR AREAS CLOSELY...BUT THE THREAT
OF FLASH FLOODING WAS NOT SIGNIFICANT ENOUGH FOR A WATCH HEADLINE.
FINALLY...NOTE THAT SOME HIGH-ELEVATION SNOW IS LIKELY TODAY BASED
ON WET-BULB ZERO HEIGHTS WHICH SUGGEST A SNOW LEVEL PERHAPS AS LOW
AS 8700 FT MSL. THE BEARTOOTH HIGHWAY IS A GOOD CANDIDATE FOR SOME
SNOW.
TONIGHT...BASED ON THE MULTI-MODEL CONSENSUS...WE KEPT CATEGORICAL
POPS IN THE FORECAST UNTIL 06 UTC FROM HYSHAM AND SHERIDAN EAST TO
BAKER AND EKALAKA. LIKELY POPS ARE EVEN IN PLAY AT BILLINGS DURING
THE EVENING. BY THIS POINT IN TIME...DEEP MOIST CONVECTION WILL BE
ESTABLISHED OVER PARTS OF THE DAKOTAS AND NEBRASKA...AND THAT DOES
POSE THE RISK OF DISRUPTING MOISTURE ADVECTION INTO OUR AREA. EVEN
SO...THE EXPECTED QG-FORCING SHOULD STILL YIELD PRECIPITATION EAST
OF THE 500-HPA TROUGH AXIS. A DRYING TREND WILL BEGIN ACROSS SOUTH
CENTRAL MT OVERNIGHT AS THAT AXIS HEADS EASTWARD.
SUN...WE LINGERED SOME CHANCE POPS FROM MILES CITY TO BAKER DURING
THE MORNING IN RESPECT TO THE BIT SLOWER DEPARTURE OF THE MID- AND
UPPER-LEVEL TROUGH ADVERTISED BY MOST 00 UTC GUIDANCE. WE ACTUALLY
EVEN LEFT LOW POPS IN BAKER AFTER 18 UTC. HOWEVER...IN GENERAL THE
WHOLE AREA WILL HAVE A DRYING AND WARMING TREND AS FLOW ALOFT WILL
BECOME WESTERLY BY AFTERNOON. MIXING TO 700 HPA OR DEEPER BASED ON
FORECAST SOUNDINGS SUPPORTS HIGHS WELL INTO THE 70S F. SCHULTZ
.LONG TERM...VALID FOR MON...TUE...WED...THU...FRI...
EXTENDED FORECAST STARTS MONDAY AS THE FLOW OPENS UP TO THE
SOUTHWEST AGAIN. WEAK SHORTWAVES GET PULLED ACROSS THE AREA MONDAY
AFTERNOON BUT THE ATMOSPHERE IS PROGGED TO BE FAIRLY DRY SO WILL
KEEP POPS LOW. A STRONG SHORTWAVE IS PROGGED BY THE GFS TO SWING
ACROSS WESTERN ZONES MONDAY EVENING AND THIS SHOULD GENERATE
SCATTERED THUNDERSTORMS AS MOISTURE GETS PULLED IN WITH THIS
SYSTEM.
THE BEST CHANCE OF PRECIPITATION DURING THE EXTENDED PERIOD LOOKS
TO BE ON TUESDAY. HEIGHTS LOWER AS SEVERAL SHORTWAVES DRIFT ACROSS
WITH A STRONG WAVE EARLY IN THE DAY. TIMING OF THIS WAVE MAY BE
PROBLEMATIC AS IT MAY BE TOO EARLY TO TAP INTO THE STRONGEST
INSTABILITY. THAT BEING SAID...PRECIPITABLE WATERS RISE TO OVER
THREE QUARTERS OF AN INCH. LOW LEVEL FLOW DOES TURN WESTERLY AND
THIS MAY DRY OUT THE LOW LEVELS AND LIMIT PRECIP POTENTIAL. THAT
WILL NEED TO BE WATCHED. WILL KEEP SCATTERED POPS IN FOR NOW BUT
MAY NEED TO BE LOWERED IN THE FUTURE.
A STRONG UPPER RIDGE IS FORECAST TO BUILD WEDNESDAY THROUGH NEXT
WEEKEND. SUBTLE DIFFERENCES STARTING TO SHOW UP THOUGH AS THE
MODELS JUST NOW STARTED TO BUILD THE RIDGE A LITTLE FARTHER WEST
AND SET UP WEAK NORTHWEST FLOW OVER THE AREA. HEIGHTS WERE NOT
QUITE AS HIGH AS PREVIOUS RUNS EITHER. THIS WILL BE A TREND TO BE
WATCHED AS THE ECMWF HINTED AT THE SAME THING. DID RAISE FORECAST
HIGHS THROUGH THE END OF THE WEEK AS 700MB TEMPERATURES WERE A
LITTLE TO WARM FOR INHERITED FORECAST HIGHS. TWH
&&
.AVIATION...
SHOWERS AND THUNDERSTORMS WILL IMPACT THE FORECAST AREA TODAY.
THE MOST WIDESPREAD HEAVY RAINFALL WILL BE EAST OF KBIL TO KSHR.
NUMEROUS SHOWERS AND THUNDERSTORMS ARE EXPECTED WEST OF THIS LINE
AS WELL. MVFR FLIGHT CONDITIONS CAN BE EXPECTED WITH THE HEAVY
RAIN. CONDITIONS WILL IMPROVE THIS EVENING IN THE WEST...OVERNIGHT
IN CENTRAL ZONES AND EARLY SUNDAY OUT EAST. CHURCH
&&
.PRELIMINARY POINT TEMP/POPS...
TDY SUN MON TUE WED THU FRI
-------------------------------------------------------
BIL 068 051/078 054/086 062/086 058/085 059/087 058/089
9/T 61/B 11/B 23/T 31/B 10/U 00/U
LVM 065 041/079 046/083 054/081 053/083 052/085 053/085
8/T 51/B 13/T 34/T 31/B 11/U 11/U
HDN 070 049/078 052/087 059/088 057/087 059/088 059/090
9/T 61/B 11/B 22/T 21/B 11/U 10/U
MLS 073 055/079 056/088 062/088 060/087 059/087 060/087
9/T 83/T 11/B 22/T 21/B 10/U 01/U
4BQ 071 049/079 054/087 059/089 058/089 059/089 059/088
9/T 82/T 11/B 22/T 21/B 11/U 11/U
BHK 070 053/075 054/086 059/086 058/086 059/083 058/084
8/T 83/T 13/T 32/T 21/U 11/U 11/U
SHR 069 045/076 049/085 055/086 053/086 054/086 053/087
+/T 81/U 11/B 22/T 21/B 11/U 11/U
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
321 AM MDT SAT JUN 22 2013
.SHORT TERM...VALID FOR TDY AND SUN...
WIDESPREAD SHOWERS AND STORMS ARE STILL EXPECTED ACROSS THE REGION
THIS AFTERNOON AND EVENING AS THE 500-HPA LOW NEAR BOISE AT 09 UTC
OPENS UP AND SWINGS ACROSS MT. LOCALLY HEAVY RAINFALL IS LIKELY.
FIRST OF ALL...WE WILL INCLUDE SOME PATCHY FOG IN THE FORECAST FOR
PLACES LIKE BAKER AND MILES CITY UNTIL 15 UTC. LOW TEMPERATURE-DEW
POINT SPREADS AS OF 09 UTC AND HRRR FORECASTS BOTH SUPPORT THAT.
TODAY...THE SCATTERED STORMS WHICH HAVE BEEN DEVELOPING OVER SOUTH
CENTRAL MT OVERNIGHT SHOULD LARGELY EXIT THE AREA BY 12 UTC AS THE
RIGHT ENTRANCE REGION OF THE 75+ KT 300-HPA JET STREAK WHICH SEEMS
RESPONSIBLE FOR THIS ACTIVITY HEADS NORTHEAST. MEANWHILE...FORCING
TIED TO THE 500-HPA TROUGH MAY BE A BIT DELAYED WHEN COMPARED WITH
EARLIER EXPECTATIONS. MOST 00 UTC GUIDANCE PICKED UP ON A BIT OF A
SLOW-DOWN WITH THIS SYSTEM...AND THAT LOOKS LIKE A GOOD SIMULATION
SINCE WE STILL HAVE A CLOSED LOW INSTEAD OF AN OPEN WAVE ACROSS ID
EARLY THIS MORNING. BASED ON THIS...WE DECIDED TO ADVERTISE MAINLY
CHANCE POPS ACROSS MUCH OF THE AREA FROM 12 TO 18 UTC...EXPECT OUT
AROUND LIVINGSTON WHERE FORCING MAY ARRIVE BY LATE MORNING. THE 00
UTC MULTI-MODEL CONSENSUS STILL SUPPORTS CATEGORICAL POPS FOR MOST
OF THE AREA THIS AFTERNOON WHEN STRONGER VERTICAL MOTION SHOWS UP.
PRECIPITABLE WATER VALUES OF 0.75 INCHES OR MORE CERTAINLY SUGGEST
LOCALLY HEAVY RAINFALL IS LIKELY. WHILE MID-LEVEL LAPSE RATES WILL
BE STEEP ENOUGH TO SUPPORT SOME THUNDER...SEVERE RISK WILL BE KEPT
IN CHECK BY A RELATIVELY COOL BOUNDARY LAYER AND RESULTANT LACK OF
CAPE. WE WILL BE WATCHING BURN SCAR AREAS CLOSELY...BUT THE THREAT
OF FLASH FLOODING WAS NOT SIGNIFICANT ENOUGH FOR A WATCH HEADLINE.
FINALLY...NOTE THAT SOME HIGH-ELEVATION SNOW IS LIKELY TODAY BASED
ON WET-BULB ZERO HEIGHTS WHICH SUGGEST A SNOW LEVEL PERHAPS AS LOW
AS 8700 FT MSL. THE BEARTOOTH HIGHWAY IS A GOOD CANDIDATE FOR SOME
SNOW.
TONIGHT...BASED ON THE MULTI-MODEL CONSENSUS...WE KEPT CATEGORICAL
POPS IN THE FORECAST UNTIL 06 UTC FROM HYSHAM AND SHERIDAN EAST TO
BAKER AND EKALAKA. LIKELY POPS ARE EVEN IN PLAY AT BILLINGS DURING
THE EVENING. BY THIS POINT IN TIME...DEEP MOIST CONVECTION WILL BE
ESTABLISHED OVER PARTS OF THE DAKOTAS AND NEBRASKA...AND THAT DOES
POSE THE RISK OF DISRUPTING MOISTURE ADVECTION INTO OUR AREA. EVEN
SO...THE EXPECTED QG-FORCING SHOULD STILL YIELD PRECIPITATION EAST
OF THE 500-HPA TROUGH AXIS. A DRYING TREND WILL BEGIN ACROSS SOUTH
CENTRAL MT OVERNIGHT AS THAT AXIS HEADS EASTWARD.
SUN...WE LINGERED SOME CHANCE POPS FROM MILES CITY TO BAKER DURING
THE MORNING IN RESPECT TO THE BIT SLOWER DEPARTURE OF THE MID- AND
UPPER-LEVEL TROUGH ADVERTISED BY MOST 00 UTC GUIDANCE. WE ACTUALLY
EVEN LEFT LOW POPS IN BAKER AFTER 18 UTC. HOWEVER...IN GENERAL THE
WHOLE AREA WILL HAVE A DRYING AND WARMING TREND AS FLOW ALOFT WILL
BECOME WESTERLY BY AFTERNOON. MIXING TO 700 HPA OR DEEPER BASED ON
FORECAST SOUNDINGS SUPPORTS HIGHS WELL INTO THE 70S F. SCHULTZ
.LONG TERM...VALID FOR MON...TUE...WED...THU...FRI...
EXTENDED FORECAST STARTS MONDAY AS THE FLOW OPENS UP TO THE
SOUTHWEST AGAIN. WEAK SHORTWAVES GET PULLED ACROSS THE AREA MONDAY
AFTERNOON BUT THE ATMOSPHERE IS PROGGED TO BE FAIRLY DRY SO WILL
KEEP POPS LOW. A STRONG SHORTWAVE IS PROGGED BY THE GFS TO SWING
ACROSS WESTERN ZONES MONDAY EVENING AND THIS SHOULD GENERATE
SCATTERED THUNDERSTORMS AS MOISTURE GETS PULLED IN WITH THIS
SYSTEM.
THE BEST CHANCE OF PRECIPITATION DURING THE EXTENDED PERIOD LOOKS
TO BE ON TUESDAY. HEIGHTS LOWER AS SEVERAL SHORTWAVES DRIFT ACROSS
WITH A STRONG WAVE EARLY IN THE DAY. TIMING OF THIS WAVE MAY BE
PROBLEMATIC AS IT MAY BE TOO EARLY TO TAP INTO THE STRONGEST
INSTABILITY. THAT BEING SAID...PRECIPITABLE WATERS RISE TO OVER
THREE QUARTERS OF AN INCH. LOW LEVEL FLOW DOES TURN WESTERLY AND
THIS MAY DRY OUT THE LOW LEVELS AND LIMIT PRECIP POTENTIAL. THAT
WILL NEED TO BE WATCHED. WILL KEEP SCATTERED POPS IN FOR NOW BUT
MAY NEED TO BE LOWERED IN THE FUTURE.
A STRONG UPPER RIDGE IS FORECAST TO BUILD WEDNESDAY THROUGH NEXT
WEEKEND. SUBTLE DIFFERENCES STARTING TO SHOW UP THOUGH AS THE
MODELS JUST NOW STARTED TO BUILD THE RIDGE A LITTLE FARTHER WEST
AND SET UP WEAK NORTHWEST FLOW OVER THE AREA. HEIGHTS WERE NOT
QUITE AS HIGH AS PREVIOUS RUNS EITHER. THIS WILL BE A TREND TO BE
WATCHED AS THE ECMWF HINTED AT THE SAME THING. DID RAISE FORECAST
HIGHS THROUGH THE END OF THE WEEK AS 700MB TEMPERATURES WERE A
LITTLE TOO WARM FOR INHERITED FORECAST HIGHS. TWH
&&
.AVIATION...
SHOWERS AND THUNDERSTORMS WILL DRIFT NORTH OF BILLINGS EARLY THIS
MORNING. THESE STORMS WILL HAVE HEAVY RAIN PRODUCING LOCAL MVFR
FLYING CONDITIONS. MORE SHOWERS AND THUNDERSTORMS WILL DEVELOP
OVER SOUTHERN SECTIONS BY LATE MORNING AND DRIFT NORTH TO
NORTHEAST THROUGH THE DAY. LOCAL MVFR CONDITIONS CAN BE EXPECTED
WITH HEAVY RAIN. THE MOSTLY LIKELY LOCATION FOR THE HEAVIEST RAIN
LOOKS TO BE EAST OF A BILLINGS TO SHERIDAN LINE...BUT CERTAINLY
SCATTERED STORMS WEST OF THIS LINE WILL CONTAIN HEAVY RAIN TOO.
THE SHOWERS WILL SHIFT OUT OF THE WEST THIS EVENING...CENTRAL
ZONES OVERNIGHT AND THE EAST EARLY SUNDAY. TWH
&&
.PRELIMINARY POINT TEMP/POPS...
TDY SUN MON TUE WED THU FRI
-------------------------------------------------------
BIL 068 051/078 054/086 062/086 058/085 059/087 058/089
9/T 61/B 11/B 23/T 31/B 10/U 00/U
LVM 065 041/079 046/083 054/081 053/083 052/085 053/085
8/T 51/B 13/T 34/T 31/B 11/U 11/U
HDN 070 049/078 052/087 059/088 057/087 059/088 059/090
9/T 61/B 11/B 22/T 21/B 11/U 10/U
MLS 073 055/079 056/088 062/088 060/087 059/087 060/087
8/T 83/T 11/B 22/T 21/B 10/U 01/U
4BQ 071 049/079 054/087 059/089 058/089 059/089 059/088
9/T 82/T 11/B 22/T 21/B 11/U 11/U
BHK 070 053/075 054/086 059/086 058/086 059/083 058/084
8/T 83/T 13/T 32/T 21/U 11/U 11/U
SHR 069 045/076 049/085 055/086 053/086 054/086 053/087
+/T 81/U 11/B 22/T 21/B 11/U 11/U
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
634 PM CDT SUN JUN 23 2013
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 317 PM CDT SUN JUN 23 2013
MORNING MAP ANALYSIS INDICATES QUASI ZONAL TO SOUTHWESTERLY MID TO
UPPER LEVEL FLOW OVER THE WESTERN HALF OF THE CONUS...WITH A
LONGWAVE RIDGE OVER THE EAST. A COUPLE OF MID LEVEL SHORT WAVES ARE
ALSO NOTED...WITH ONE EXTENDING FROM THE UPPER MISSISSIPPI VALLEY
INTO THE NORTHERN PLAINS...AND THE OTHER OVER THE SOUTHWESTERN
CONUS. MID TO UPPER LEVEL JET ENERGY EXTENDS FROM THE
WEST/SOUTHWESTERN CONUS...EAST/NORTHEAST INTO THE CENTRAL
PLAINS...AND THEN NORTH INTO SOUTH CENTRAL CANADA BEFORE FLOWING
EAST INTO SOUTHEASTERN CANADA AND PORTIONS OF THE NORTHEASTERN
CONUS. MID TO UPPER LEVEL FLOW OVER OUR AREA MAXES OUT AT AROUND
60KTS BETWEEN 300MB AND 200MB PER 12Z SOUNDING DATA FROM KLBF AND
KOAX. WATER VAPOR IMAGERY ALSO SHOWS THE AFOREMENTIONED MID LEVEL
SHORT WAVES...ALONG WITH A PAIR OF CLOSED MID LEVEL LOWS. ONE SUCH
LOW IS LOCATED OVER EASTERN ALBERTA AND WESTERN SASKATCHEWAN...AND
THE OTHER IS OVER THE PACIFIC JUST OFF THE COAST OF THE NORTHWESTERN
CONUS. AT THE SURFACE AN AREA OF LOW BAROMETRIC PRESSURE EXISTS OVER
SOUTHWESTERN KANSAS...WITH A FRONTAL BOUNDARY EXTENDING
NORTHEAST FROM THE LOW INTO NORTH CENTRAL KANSAS AND
SOUTHEASTERN NEBRASKA. THE LOW LEVEL WIND FIELD ACROSS MUCH OF OUR
CWA REMAINS FROM THE NORTHEAST FOR THE MOST PART...BUT LOCATIONS
ACROSS OUR SOUTHEAST SUCH AS KK82...KK61...AND KHJH ARE ALL
OBSERVING A SURFACE WIND FROM THE SOUTHEAST.
GUIDANCE FROM THE NAM...OPERATIONAL GFS...EC...AND SREF-MEAN
SUGGESTS THE LOW LEVEL BAROCLINIC ZONE WILL PERSIST OVER
SOUTHEASTERN PORTIONS OF OUR CWA THIS EVENING INTO TONIGHT BEFORE
SURGING NORTH DURING THE DAY MONDAY. THERE ARE
INDICATIONS...ESPECIALLY FROM HIGHER RESOLUTION MODELS SUCH AS THE
NAM12...OF VERY SUBTLE MID LEVEL PERTURBATIONS MOVING OVERHEAD
WITHIN THE MEAN FLOW THIS AFTERNOON AND THIS EVENING. CONFIDENCE ON
SUCH A FEATURE PROMOTING PRECIPITATION PRODUCTION ACROSS OUR AREA
THIS AFTERNOON AND EVENING REMAINS VERY LOW HOWEVER AND AS A
RESULT...WILL CONTINUE RELEGATING ANY AFTERNOON AND EVENING POPS TO
OUR SOUTH/SOUTHEASTERN CWA...IN CLOSEST PROXIMITY TO THE
AFOREMENTIONED LOW LEVEL BAROCLINIC ZONE AND RESULTANT AXIS OF
ENHANCED LOW LEVEL CONVERGENCE AND LIFT. AS FOR THE TIMING OF
CONVECTIVE INITIATION THIS AFTERNOON AND EVENING...FORECAST PROXIMITY
SOUNDINGS FROM THE NAM...OPERATIONAL GFS...AND RAP ALL SUGGEST A
HEALTHY CAP PERSISTING THROUGH AT LEAST 00Z. GIVEN THIS...ITS HARD
TO BUY INTO QPF FIELDS FROM THE NAM...OPERATIONAL GFS...EC...AND
SREF-MEAN...WHICH ALL SUGGEST WIDESPREAD PRECIPITATION WILL BE REALIZED ACROSS
PORTIONS OF OUR SOUTHEAST BEFORE 00Z THIS EVENING. HRRR SIMULATED
REFLECTIVITY LOOKS MUCH MORE REASONABLE...SUGGESTING VERY ISOLATED
CONVECTION OCCURRING ACROSS OUR SOUTHEAST TOWARDS 00Z. GIVEN ALL
THIS...CONFIDENCE IS VERY LOW THAT MUCH PRECIPITATION WILL BE
REALIZED ACROSS OUR AREA PRIOR TO 00Z...BUT CANNOT COMPLETELY RULE
OUT SUCH A SOLUTION AND WILL MAINTAIN ~20% POPS ACROSS OUR SOUTHEAST
23-00Z. 00Z AND BEYOND...FORECAST PROXIMITY SOUNDINGS SUGGEST THE CAPPING
INVERSION WILL WEAKEN SOMEWHAT THUS MAKING CONVECTION SOMEWHAT MORE
LIKELY...A SOLUTION SUPPORTED BY QPF FIELDS FROM THE
NAM...OPERATIONAL GFS...EC...AND SREF-MEAN...AS WELL AS SIMULATED
REFLECTIVITY FROM THE HRRR. GIVEN THIS...WILL GO AHEAD WITH SLIGHTLY
HIGHER POPS...~%30...00-06Z ACROSS OUR SOUTHEAST. SHOULD
SURFACE-BASED CONVECTION BE REALIZED THIS AFTERNOON AND/OR
EVENING...THEN SEVERE WEATHER WILL LIKELY RESULT WITH DEEP LAYER
MUCAPE VALUES IN THE 2000-4000J/KG WAITING FOR UPDRAFT PRODUCTION
AND 30-35KTS OF DEEP LAYER BULK SHEAR FOR UPDRAFT ENHANCEMENT.
CERTAINLY LARGE HAIL AND MICROBURST-RELATED WIND GUSTS WILL BE A
THREAT...BUT ENHANCED HORIZONTAL VORTICITY IN THE VICINITY OF THE
LOW LEVEL BAROCLINIC ZONE COULD ALSO PROMOTE ISOLATED TORNADIC
ACTIVITY. WILL CONTINUE SUCH WORDING IN THE HWO AS A RESULT.
HEADING INTO THE OVERNIGHT HOURS TONIGHT...THE AXIS OF A ~45KT 850MB
JET STREAK IS EXPECTED TO DEVELOP ACROSS PORTIONS OF WESTERN AND
CENTRAL KANSAS...WITH THE NOSE OF THIS LOW LEVEL JET MOVING INTO
SOUTHERN PORTIONS OF OUR CWA BETWEEN 06Z AND 12Z. SHOULD DEEP
CONVECTION BE ONGOING ALONG THE LOW LEVEL BAROCLINIC ZONE...THEN
INCREASING LOW LEVEL THERMAL ADVECTION ALONG THE AXIS OF THE LOW
LEVEL JET COULD CERTAINLY HELP INCREASE SPATIAL COVERAGE OF SAID
CONVECTIVE ACTIVITY. ALSO...IN ADDITION TO POSSIBLE THUNDERSTORM
ACTIVITY OVER PORTIONS OF OUR CWA THIS AFTERNOON AND
EVENING...THUNDERSTORMS ALSO REMAIN POSSIBLE OVER THE CENTRAL HIGH
PLAINS. SHOULD HIGH PLAINS CONVECTION DEVELOP THIS AFTERNOON/EVENING
AND MOVE EAST TOWARDS OUR AREA TONIGHT...ADDITIONAL SHOWER AND
THUNDERSTORM ACTIVITY COULD BE REALIZED OVER OUR AREA
TONIGHT...ESPECIALLY OUR WEST. THIS IS A SOLUTION SUPPORTED BY THE
NAM...OPERATIONAL GFS...SREF-MEAN...AND HRRR. GIVEN ALL THIS...WENT
AHEAD WITH RELATIVELY HIGHER POPS ACROSS MUCH OF THE CWA STARTING
AROUND 06Z. SEVERE WEATHER COULD CERTAINLY BE POSSIBLE DURING THE
EARLY PART OF THE OVERNIGHT HOURS AS THE MORE ROBUST CONVECTION FROM
EARLIER IN THE EVENING...SHOULD IT DEVELOP...MAINTAINS ITSELF. THAT
BEING SAID...BARRING THE DEVELOPMENT OF AN MCS ACROSS THE
REGION...CONVECTIVE ACTIVITY SHOULD WANE IN INTENSITY AS POTENTIAL
INSTABILITY DECREASES 06Z ONWARD.
THERE COULD SOME LINGERING SHOWER AND THUNDERSTORM ACTIVITY ACROSS
OUR AREA AROUND SUNRISE MONDAY...BUT OTHERWISE MONDAY DURING THE DAY
IS EXPECTED TO REMAIN DRY FOR THE MOST PART AS THE WARM FRONT SURGES
NORTH AND AN OVERALL LACK IN KINEMATIC FORCING OVERTAKES THE AREA.
AT THIS TIME THE ONLY REAL THREAT FOR PRECIPITATION DURING THE DAY
MONDAY APPEARS AS THOUGH IT WILL RESIDE OVER OUR SOUTHWESTERN CWA
DURING THE LATE AFTERNOON AND EVENING HOURS...WHICH IS WHERE AND
WHEN GUIDANCE SUGGESTS AN ADVANCING LOW LEVEL DRY LINE WILL BULGE EAST.
AN AREA OF LOCALLY ENHANCED CONVERGENCE AND LIFT IN THE VICINITY OF
THIS DRY LINE BULGE...WORKING IN CONCERT WITH DIABATIC HEATING...MAY
BE ENOUGH TO INITIALIZE ISOLATED SHOWER AND THUNDERSTORM DEVELOPMENT
AND AS A RESULT...~20% POPS ARE FORECAST 21Z MONDAY THROUGH 00Z
TUESDAY ACROSS OUR SOUTHWEST. SHOULD THUNDERSTORM ACTIVITY BE REALIZED LATE
MONDAY AFTERNOON AND/OR EVENING...THEN DEEP LAYER MUCAPE VALUES OF
2000-3000J/KG...ALONG WITH DEEP LAYER BULK SHEAR VALUES OF
~30KTS...WILL BE AVAILABLE FOR UPDRAFT PRODUCTION AND ENHANCEMENT.
GIVEN THIS...WILL GO AHEAD AND HIGHLIGHT THE THREAT FOR ISOLATED
SEVERE WEATHER ACROSS OUR SOUTHWEST MONDAY AFTERNOON AND EVENING.
FINALLY...INCREASING SOUTHERLY FLOW WILL LIKELY BE OBSERVED MONDAY
AFTERNOON ONCE THE SURFACE WARM FRONT SURGES NORTH. GUIDANCE
SUGGESTS A SUSTAINED WIND OF ~24KTS...WITH HIGHER GUSTS APPROACHING
35KTS...WILL BE REALIZED PRIMARILY ACROSS NORTH CENTRAL KANSAS. AS A
RESULT...WILL CONTINUE MENTIONING SUCH CONDITIONS IN THE HWO.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 317 PM CDT SUN JUN 23 2013
MONDAY NIGHT...A VORT MAX LOCATED OVER THE HIGH PLAINS WILL TRACK
EAST ACROSS THE FORECAST AREA. THUNDERSTORMS THAT INITIALLY FORM
ACROSS THE HIGH PLAINS DURING THE MONDAY AFTERNOON HOURS WILL SLIDE
EAST DURING THE EVENING AND OVERNIGHT HOURS...AND IF THEY HOLD
TOGETHER MAY BRING RAIN TO PORTIONS OF THE FORECAST AREA. IN
ADDITION TO RAIN...SOME OF THESE THUNDERSTORMS MAY BE SEVERE WITH
LARGE HAIL AND DAMAGING WINDS POSSIBLE DURING THE EVENING HOURS.
INSTABILITY IS HIGH AND DEEP LAYER SHEAR IS MORE MODEST BUT
SUFFICIENT FOR SEVERE STORMS. THE LIMITING FACTOR WILL BE THE WARM
MID LEVEL CAP AND THUS CONFIDENCE IN THUNDERSTORM DEVELOPMENT AND
COVERAGE IS STILL FAIRLY LOW WITH SLIGHT POPS. THE 12Z ECMWF AND 12Z
NAM FAVOR OUR WEST AND NORTH FOR STORMS...WHILE THE 12Z GFS
HIGHLIGHTS OUR SOUTHEASTERN ZONES. THE ECMWF AND NAM MAKE MORE SENSE
WITH FAVORING NORTH AND WEST ZONES BASED ON THE EXPECTED UPPER WAVE
LOCATION AND THE INCREASING STRENGTH OF THE CAP AS YOU HEAD SOUTH.
TUESDAY AND WEDNESDAY...THE PATTERN WILL BE FAIRLY ZONAL WITH ALL
OF THE BETTER UPPER FLOW AND SHORT WAVES TRACKING ACROSS THE
NORTHERN TIER STATES. AN UPPER RIDGE WILL SLOWLY BEGIN TO BUILD
ACROSS THE SOUTHWEST CONUS STARTING ON WEDNESDAY. A SFC TROUGH AXIS
WILL TRACK EAST THROUGH OUR FORECAST AREA LATE ON TUESDAY AND TURN
THE WINDS TO NORTHERLY BY WEDNESDAY. HOWEVER...A STRONG CAP SHOULD
RESULT IN DRY CONDITIONS FOR MOST AREAS AND WILL CONTINUE TO CALL
FOR A DRY FORECAST...BUT CAN NOT COMPLETELY RULE OUT AN ISOLATED
THUNDERSTORM...HENCE THE 10 PERCENT POPS. TUESDAY WILL BE SCORCHER
WITH HIGHS WELL INTO THE 90S ACROSS NEBRASKA TO OVER 100 ACROSS MUCH
OF NORTHERN KANSAS. TEMPERATURES WILL FALL A FEW DEGREES WITH THE
NORTH WINDS ON WEDNESDAY...BUT CONTINUE TO EXPECT 90S FOR HIGHS.
THURSDAY THROUGH SUNDAY...THERE IS A SHIFT IN THE UPPER PATTERN AS
AN UPPER RIDGE STRENGTHENS ACROSS THE ROCKIES AND AN UPPER TROUGH
PERSISTS ACROSS THE EASTERN CONUS. THIS WILL RESULT IN NORTHWESTERLY
FLOW ALOFT FOR OUR FORECAST AREA. MOST AREAS WILL BE DRY THROUGHOUT
THIS PERIOD GIVEN A LACK OF FORCING. THERE IS A SLIGHT CHANCE OF
THUNDERSTORMS ON THURSDAY INTO THURSDAY NIGHT...BUT MOST RESENT
MODEL RUNS ARE STARTING TO BACK OFF OF THIS ALREADY RATHER SLIGHT
CHANCE OF PRECIPITATION. ANOTHER WEAK COOL FRONT WILL TRY TO WORK
ITS WAY THROUGH AT SOME POINT THURSDAY NIGHT OR FRIDAY...BUT THURSDAY
SHOULD STILL BE A HOT DAY WITH 90S ACROSS NEBRASKA TO NEAR 100 IN
KANSAS. THE COOLER WEATHER WILL SETTLE IN ON FRIDAY AND SATURDAY
WITH EASTERLY TO NORTHEASTERLY SFC WINDS. THIS COOLER FETCH SHOULD
DROP HIGHS BACK INTO THE LOWER AND MID 90S ON FRIDAY...AND THEN 80S
ACROSS NEBRASKA TO LOWER 90S OVER KANSAS ON SATURDAY. TEMPERATURES
BEGIN TO WARM BACK UP ON SUNDAY WITH EVERYONE BACK IN THE 90S.
OVERALL...TEMPERATURES WILL NOT VARY THAT MUCH AND REMAIN RATHER
TOASTY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 622 PM CDT SUN JUN 23 2013
CIGS AT KGRI HAVE INTERMITTENTLY DROPPED TO MVFR...BUT LOOK FOR OVERALL
SCATTERED MVFR TO VFR CLOUDS THIS EVENING. WINDS WILL BE LIGHT
AND VARIABLE AS A WARM FRONTAL BOUNDARY RESIDES JUST SOUTH OF THE
TERMINAL. AN OUTSIDE OF THUNDERSTORMS EXIST DURING THE OVERNIGHT
HOURS AS CONVECTION ALONG THE HIGH PLAINS ROLLS EASTWARD. AS THE
WARM FRONT LIFTS NORTH...SOUTHERLY WINDS WILL INCREASE ON MONDAY
WITH GUSTS NEAR 25KTS POSSIBLE. CLOUDS SHLD REMAIN AT VFR LEVELS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...BRYANT
LONG TERM...WESELY
AVIATION...FAY
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
343 PM CDT SAT JUN 22 2013
.DISCUSSION...
THUNDERSTORM CHANCES THROUGH SUNDAY OR MONDAY...THEN WARMING NEXT
WEEK...REMAIN THE PRIMARY FORECAST CONCERNS.
THUNDERSTORMS THAT DEVELOPED IN WESTERN NEBRASKA FRIDAY
AFTERNOON/EVENING HELD TOGETHER OVERNIGHT FUELED BY THETA-E
ADVECTION ON NOSE OF LOW LEVEL JET. STORMS SWEPT ACROSS MUCH OF
EASTERN NEBRASKA AND WEST CENTRAL IOWA DURING THE MORNING BUT HAD
DECREASED MARKEDLY BY LATE MORNING. ATTENDANT CLOUD SHIELD HELD
TEMPERATURES DOWN MUCH OF THE MORNING...BUT RETURNING SOUTH WINDS
AND MORE SUNSHINE THIS AFTERNOON PUSHED TEMPERATURES TOWARD OR ABOVE
90 IN ALL BUT NORTHEAST NEBRASKA WHERE TEMPS LAGGED IN THE UPPER
70S OR LOWER 80S. DEW POINTS WERE BETWEEN 65 AND 70.
LOOKS LIKE MORNING CONVECTION HAS STABILIZED ATMOSPHERE FOR LATE
AFTERNOON ACTIVITY FOR THE MOST PART. RAP MESOANALYSIS SHOWS
MUCAPE VALUES WELL OVER 2000 J/KG IN THE SOUTHERN HALF OF THE
CWA...BUT LOW LEVEL CONVERGENCE IS NEGLIGIBLE. MEANWHILE IN THE
NORTHEAST WHERE SOME SURFACE CONVERGENCE IS NOTED...COOLER
SURFACE TEMPS BEHIND EXITING CONVECTION HAS KEPT MUCAPE LOW.
EXPECT THAT TO ERODE LATER THIS EVENING AS A MID LEVEL IMPULSE
MOVING OUT OF EASTERN COLORADO/WYOMING COOLS MID LEVEL ATMOSPHERE
AS SURFACE TEMPERATURES REBOUND SOMEWHAT. BETTER CHANCES FOR
EVENING CONVECTION LIES TO OUR WEST WHERE CAPES ARE INCREASING AND
CAP DIMINISHING...AND LATEST MESO DISCUSSIONS FROM SPC SUGGEST
WATCH IS LIKELY FOR PARTS OF WESTERN AND CENTRAL NEBRASKA. THESE
STORMS WILL MOVE NORTHEAST TOWARD NORTHEAST NEBRASKA...THEN
PROPAGATE SOUTHEAST WITH TIME AS LOW LEVEL JET KICKS IN
OVERNIGHT...PROBABLY REACHING THE I-80 CORRIDOR LATE TONIGHT.
SEVERE THREAT SHOULD WANE AFTER MIDNIGHT...BUT ANY OF THE STRONGER
STORMS COULD PRODUCE WIND AND POSSIBLY HAIL AS FREEZING LEVELS
HAVE COME DOWN SOME FROM YESTERDAY.
WOULD EXPECT A DECREASING TREND AGAIN SUNDAY MORNING...THEN
REDEVELOPMENT IN THE AFTERNOON ALONG COLD FRONT THAT WILL BE
DRIFTING INTO THE NORTHWEST CWA IN THE MORNING. WHERE THAT FRONT
WILL SET UP WILL BE AFFECTED BY MORNING CONVECTION...BUT MOST
LIKELY WILL LIE SOMEWHERE CLOSE TO I-80 CORRIDOR IN THE
AFTERNOON. SUNSHINE AND POOLING DEW POINTS ALONG FRONT WILL YIELD
CAPES CLOSE TO 3000 J/KG ALONG WITH 30KT 0-6KM SHEAR. FRONTAL
CONVERGENCE UNDER STEEP LAPSE RATES NEAR 8 C/KM SUGGEST STORMS
WILL FIRE LATE IN THE DAY AS CAP WEAKENS. ALL MODES OF SEVERE ARE
POSSIBLE...AS SHEAR/INSTABILITY AND LOWERING FREEZING LEVELS POINT
TO WIND AND HAIL. AND LOW LEVEL VORTICITY/HELICITY/EHI SUPPORT AN
ISOLATED TORNADO THREAT.
EXPECT STORMS TO CONTINUE THROUGH THE EVENING WITH SEVERE THREAT
GRADUALLY DIMINISHING LATE IN THE EVENING. AGAIN ANOTHER ROUND OF
STORMS FROM THE HIGH PLAINS MAY ROLL ACROSS NORTHERN CWA AFTER
MIDNIGHT.
AFTER MORNING CONVECTION MONDAY...MUCH OF NEXT WEEK LOOKS DRY AS
HEIGHTS BUILD FROM THE SOUTHWEST AND SOUTH INTO THE CENTRAL PLAINS.
HOWEVER ANOTHER ROUND OF STORMS MONDAY AFTERNOON...BUT WOULD FAVOR
AREAS NORTH OF NEBRASKA. BY LATE IN THE WEEK...A MID LEVEL TROUGH
DEEPENING NEAR AND NORTH OF THE GREAT LAKES COULD DRIVE A BACKDOOR
COLD FRONT INTO OUR AREA. MODELS REMAIN BEARISH WITH PRECIP CHANCES
THEN...BUT SLIGHTLY COOLER AIR WILL FOLLOW. LOOKS LIKE HIGHS IN THE
90S WILL BE COMMON THROUGH MUCH OF THE WEEK...WITH 80S FRIDAY AND
SATURDAY.
DERGAN
&&
.AVIATION...18Z TAFS FOR KOMA...KLNK...AND KOFK.
SOUTHEAST WINDS WILL REMAIN STRONG 14 TO 22KTS SUSTAINED WITH
GUSTS 20 TO 30KTS...DECREASING TONIGHT...HOWEVER LLWS DEVELOPS BY
06Z. VFR CONDITIONS FOR NOW WITH BREAK IN THE PRECIPITATION.
THUNDERSTORMS MAY DEVELOP IN THE KOFK AREA LATER THIS AFTERNOON OR
EVENING...HOWEVER FOR NOW INCLUDED MVFR VSBYS WITH THE
PRECIPITATION LATER THIS EVENING AND OVERNIGHT AT ALL THREE
SITES.
ZAPOTOCNY
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
251 PM EDT SAT JUN 22 2013
.SYNOPSIS...
HIGH PRESSURE BUILDING INTO THE NORTHEAST WILL BRING WARM
TEMPERATURES TO THE REGION. INCREASING HUMIDITY LEVELS MAY PROVIDE
THE SPARK FOR A FEW AFTERNOON THUNDERSTORMS THROUGH THE PERIOD. AN
UPPER LEVEL TROUGH WILL SKIRT THROUGH BY MID-WEEK WITH A BETTER
CHANCE FOR SHOWERS AND THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
250 PM UPDATE...
SHOWERS HV DVLPD ACRS SRN ONTARIO THIS AFTN IN CONJUNCTION WITH
S/WV. APPEARS AS THO THE BULK OF THESE SHOWERS/TSTMS WL GO ACRS NRN
ZONES GNRLY NORTH OF THE THRUWAY. ANOTHER LINE OF STORMS IS DVLPNG
ACRS WRN OH AND SLOWLY TRYING TO FILL IN IN CONVERGENCE ZONE AND
POOLING DWPTS. THE LATEST HRRR MODEL DATA THIS WL FILL IN ACRS WRN
PA AND THEN BREAK UP AS IT HEADS FURTHER EAST AWAY FM CONVERGENT
AXIS THEREFORE EXPECT CH THUNDER AFT 00Z OVR FAR NRN ZONES AND ISOLD
AT BEST ACRS REMAINDER OF NY CNTYS WITH LOSS OF DAYTIME HTG.
FCST FOR TONIGHT WL BE COMPLICATED BY TWO POTENTIAL ISSUES. ANY MCS
THAT MAY DVLP ACRS THE NRN PLAINS SPREADING HIGH CIRRUS INTO AREA. A
CLOSED H5 LOW WL DRIFT NORTHWARD FM THE SERN U.S. IN AREA OF
STRONGEST HEIGHT FALLS PER 12Z RAOBS. QUESTION WL BE HOW QUICKLY
THESE CLDS WL IMPACT AREA AND THE RESULT ON FOG DVLPMNT.
FOR NOW HV GONE WITH MOCLDY ACRS NRN ZONES DUE TO BEING CLOSER IN
PROXIMITY TO MAIN STORM TRACK AND STATIONARY BNDRY IN WHICH ANY
SUBTLE S/WVS MAY RIDE ALONG. FURTHER TO THE SOUTH, AT LEAST
INITIALLY TONIGHT SKIES WL BE MOCLR AS UL RIDGE BUILDS IN AHD OF H5
LOW EJECTING NORTH. AFT 06Z FCST WL BE TOTALLY DEPENDENT ON HOW FAST
SYSTEM CAN MV NWRD. LATEST CMC CLD FCST INDICATING CLR SKIES ALL THE
WAY THRU 12Z. 12Z NAM AND GFS INDICATE RIDGE FLATTENING SLIGHTLY
TONIGHT AND ALLOWING CLDS TO SPILL DOWN INTO NEPA THEN PUMPING BACK
UP TWD 12Z. FOR NOW, HV CALLED IT PCLDY AFT 06Z THO THIS MAY NEED
TO BE TWEAKED BY LATER SHIFTS.
AS FOR FOG POTENTIAL BL IS CERTAINLY MOIST ENUF AND WITH RVR VLYS
DROPPING DOWN THIS MRNG, SEE A REPEAT OF THIS, IF CLRNG CAN DEVELOP
ACRS SRN TIER AND POINTS SOUTH. THEREFORE WL KEEP PATCHY FOG IN
GRIDS STARTING AT 09Z AND THEN SCATTERING OUT BY 13Z. EXPECT OVRNGT
MINS TO RMN IN THE 60S AREAWIDE DUE TO CLD CVR AND H8 TEMPS INCRSG
DUE TO CONTD WAA.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
250 PM UPDATE...
SHORT TERM WL RMN AS IS WITH A CHC OF DIURNAL CONVECTION EACH AFTN
AND POTENTIAL FOR RVR VLY FOG OVRNGT. HIGHS WL TOP OUT IN THE M/U
80S EACH DAY WITH MINS DIPPING INTO THE 60S.
H5 LOW WL EJECT THRU OH VLY SUNDAY NGT WITH CHC FOR RENEGADE STORMS
AT ANYTIME ACRS THE CWA. THUS, WL KEEP MENTION OF ISOLD POPS IN FOR
MOST OF THE AREA THRU 12Z MONDAY. MAIN TROF WL ZIP THRU AREA ON
MONDAY WITH BETTER CHC FOR CONVECTION DRG THE AFTN. WV AFT WV WL
PERSIST THRU THE END OF THE SHORT TERM WITH CHC POPS EACH DAY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
MOST OPERATIONAL MODELS AND ENSEMBLES SUGGEST THAT THE PATTERN
WILL BECOME INCREASINGLY CYCLONIC ACROSS THE NORTHEASTERN US
DURING THE UPCOMING WEEK. THIS WILL TEND TO INCREASE THE CHANCES
FOR UNSETTLED CONDITIONS...ESPECIALLY HEADING THROUGH THURSDAY AND
FRIDAY WITH THE WPC ANALYSTS INDICATING THE PASSAGE OF WARM AND
COLD FRONTS EACH DAY. WITH ONLY BROAD FORCING NOTED IN THE MODELS...
NOTHING REALLY SUGGESTS THAT WE WILL BE FACING A PROLONGED SOAKING
EVENT...UNTIL POSSIBLY A SHOT WITH THE FRONTS ON FRIDAY...IF IT
OCCURS. WPC GUIDANCE SUGGESTED 60-70 POPS ON THURS-FRI BUT THIS
IS SUMMER TIME AND CONFIDENCE IS USUALLY NOT HIGH ENOUGH TO GO SO
FAR ABOVE CLIMO AT DAYS 6-7 SO HAVE GONE BELOW THE GUIDANCE AND
EVEN A TAD LOWER THAN OUR PREV FORECAST ACROSS THE BOARD GIVEN
SUCH UNCERTAINTY.
HAVE ALSO NUDGED MAX TEMPERATURES UP HIGHER THAN RECOMMENDED
GUIDANCE GIVEN LITTLE BUDGE IN THE ECMWF/GFS THERMAL FIELDS WHICH
SUGGEST ABOVE NORMAL TEMPERATURES BY 1-2 STANDARD DEVIATIONS FOR
MUCH OF THE WEEK UNTIL THE TROF REALLY KICKS IN GOING INTO NEXT WEEKEND.
SHOULD EASILY SEE UPPER 80S-AROUND 90 WEDNESDAY FOLLOWED BY TEMPS
REMAINING IN THE LOW-MID 80S ONLY TEMPERED BY CLOUDS AND SHOWERS.
MUGGY LOW-MID 60S WILL BE COMMON FOR LOWS.
&&
.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
MINOR DISTURBANCE MOVING ACROSS LOWER ONTARIO WILL ENTER N CNTRL
NY EARLY THIS AFTERNOON WITH A PERIOD OF SHRA/TSRA AFFECTING
KSYR-KRME. DIFFICULT TO ASSESS SOUTHERN EXTENT OF CONVECTIVE
DEVELOPMENT GIVEN BALANCE BETWEEN DESTABILIZATION AND MID-LEVEL
THERMAL CAPPING. FOR NOW...HAVE NOT INCLUDED ANY TSRA SOUTH OF
KSYR-KRME ALTHOUGH SOME MODEL FORECASTS SUGGEST THAT KITH-KBGM
AREAS WILL NEED TO BE MONITORED FOR CB DEVELOPMENT. BEYOND 00Z
TONIGHT...THE CONFIDENCE FOR CONVECTIVE DEVELOPMENT WANES PRETTY
QUICKLY AND HAVE NOT INCLUDED IN THIS UPDATE...ALTHOUGH MODELS
HAVE POTENTIAL ACTIVITY THROUGH 06Z...BUT WILL PLAY TYPICAL
DIURNAL TRENDS ATTM. THE MORE TROUBLESOME CONSIDERATIONS ARE FOR IFR
AND ALTERNATE VSBY RESTRICTIONS DUE TO FOG AND HAZE AS LOW LEVEL
MOISTURE WILL BE INCREASING WITH TIME. I SEE ENOUGH EVIDENCE AT
THIS TIME TO INCLUDE SOME OVERNIGHT MVFR EXTENDING ACROSS MOST
TERMINALS WITH IFR LIKELY DEVELOPING AT KELM. LOW LEVEL STRATOCU
CIGS ARE ALSO IN THE REALM OF POSSIBILITY AND HAVE TAGGED A SCT
010-020 FOOT LAYER ONTO THE VSBY RESTRICTIONS AT SVRL LOCATIONS TO
AT LEAST HINT AT THAT POTENTIAL.
WINDS GENERALLY 5-10 KTS FROM THE SOUTHWEST THIS AFTERNOON AND
SUNDAY WITH LIGHT LOCAL DRAINAGE FLOW TONIGHT.
OUTLOOK...SUN THRU WED...VFR MOST OF THE TIME. MVFR VSBY AND CIG
RESTRICTIONS POSSIBLE WITH PASSING SHRA OR TSRA.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...PVN
NEAR TERM...PVN
SHORT TERM...PVN
LONG TERM...JAB
AVIATION...JAB
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
333 AM EDT SAT JUN 22 2013
.SYNOPSIS...
HIGH PRESSURE ANCHORED OFF THE ATLANTIC COAST WILL KEEP THE NORTH
COUNTRY DRY TODAY WITH PARTLY TO MOSTLY SUNNY SKIES THIS AFTERNOON
AND TEMPERATURES IN THE MID 70S TO LOWER 80S. A WARM FRONT WILL
MOVE SLOWLY THROUGH THE AREA ON SATURDAY WITH SOME SHOWERS AND A
SLIGHT CHANCE OF A THUNDERSTORM WITH TEMPERATURES AGAIN RANGING
THROUGH THE 70S NORTHEAST TO THE LOWER 80S SOUTHWEST. EVEN WARMER
AND MORE HUMID CONDITIONS ARE EXPECTED SUNDAY INTO NEXT WEEK...WITH
DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS...MAINLY DURING THE
AFTERNOON AND EVENING HOURS.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1250 AM EDT SATURDAY...INHERITED FORECAST IN GOOD SHAPE
WITH ONLY UPDATE NEEDED TO INCREASE SKY COVER AS CONVECTIVE DEBRIS
CLOUDS ARE FILLING INTO THE REGION. WITH INCREASED CLOUD COVER
TEMPS SHOULD HOLD FAIRLY STEADY FOR THE REMAINDER OF THE NIGHT IN
THE 50S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY/...
AS OF 323 PM EDT FRIDAY...SATURDAY...MODERATE CONFIDENCE CONTINUES
THAT WE`LL SEE SOME SOME SHOWERS AND A SLIGHT CHANCE OF A
THUNDERSTORM AS THE DECAYING MCV AND SHORT WAVE TROF MOVES ACROSS
THE REGION DURING MIDDAY INTO THE EARLY EVENING. MODEL GUIDANCE
HAS BEEN STRUGGLING WITH THE PLACEMENT OF THIS FEATURE WITH THE
GFS MORE WIDESPREAD AND FURTHER SOUTH AND THE NAM FURTHER NORTH.
HAVE PLAYED IT MORE TOWARD THE GFS/MAV SOLUTION AS RAP ANALYSIS
SHOWS SIGNIFICANT MCV HAS FORMED. SO HIGHER POPS THAN WHAT THE NAM
MOS SUGGESTS AND SLIGHT COOLER TEMPERATURES. HAVE STAYED MAINLY
NEAR 80 WITH COOLER TEMPS NORTHEAST AND WARMER SOUTHWEST. WHERE
CLOUDS/SHOWERS HANG ON IT COULD BE 5 DEGREES COOLER AND WHERE THEY
DISSIPATE 5 DEGREES WARMER.
IN THE ABSENCE OF ANY LARGE SCALE FORCING...ANY CONVECTIVE
ACTIVITY WILL DISSIPATE GOING INTO THE EVENING AND OVERNIGHT
HOURS SAT NIGHT WITH LOWS MAINLY IN THE 60S.
ON SUNDAY...MORE TYPICAL ISOLATED TO SCATTERED AIRMASS TYPE PULSE
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE AGAIN ON SUNDAY MAINLY
IN THE MID TO LATE AFTERNOON/EVENING WITH ACTIVITY SETTLING DOWN
OVERNIGHT SUNDAY NIGHT. CAPE VALUES NOT ALL THAT IMPRESSIVE (BELOW
100 J/KG) WITH GFS SUGGESTING A CAPPING SUBSIDENCE INVERSION MAY
BE IN PLACE SO KEPT A MINIMAL CHANCE POPS IN THE FORECAST. IT
SHOULD BE CONSIDERABLY WARMER AND MORE HUMID AIR PUSHES IN AS THE
WARM FRONT LIFTS NORTHEAST SUNDAY WITH HIGHS IN THE 80S.
SUNDAY NIGHT SHOULD BE VERY MILD WITH READINGS IN THE 60S PERHAPS NEAR 70
AT BTV WITH WARM AND HUMID AIR FIRMLY ENTRENCHED.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 333 AM EDT SATURDAY...FOR THE EXTENDED PERIOD...BROAD UPPER
RIDGE ACROSS THE SOUTHERN HALF OF THE COUNTRY COMBINED WITH STRONG
SFC RIDGE OFFSHORE WILL ALLOW FOR WARM TEMPS ACROSS THE AREA THRU
THE PERIOD. ACCOMPANYING THESE EXPECTED TEMPS WILL ALSO BE THE
CHANCE FOR RW/TRW. MDLS CONTINUE TO SHOW ZONAL FLOW OVER THE
NORTHERN PORTION OF THE COUNTRY AS A RESULT OF UPPER RIDGE TO THE
SOUTH. 850/925 TEMPS RANGING FROM +16C TO +20C WILL BRING DAYTIME
HIGHS WELL INTO THE 80S W/ SOME LOCAL 90F...ESPECIALLY FOR FIRST
HALF OF EXTENDED. THE LATTER PORTION WILL TAPER DOWN TO NEAR 80F
AS BROAD TROUGH WORKING OUT OF THE GREAT LKS REGION BREAKS DOWN
UPPER RIDGE...ALLOWING FOR INCR CHANCES FOR CLDS/MOISTURE W/ BROAD
SW FLOW SETTING UP. OVERNGT LOWS IN THE 50S TO M60S. OVERALL FOR
PRECIP...STILL EXPECTING SCT RW/TRW THRU WEDNESDAY AS WK
SHORTWAVES WORK ALONG NORTHERN FRINGE OF UPPER RIDGE...FOLLOWED BY
MORE AREAL COVERAGE IN TRW/RW AS LOW FROM GREAT LKS APPROACHES.
SOME MDL DIFFERENCES FOR TIMING/PLACEMENT OF TROUGH FOR
THURS/FRI...SO WILL KEEP OVERALL CHANCE POPS IN ATTM. W/ AIRMASS
ON THE HUMID SIDE THRU PERIOD...HIGH PW CONTENT OF NEAR 1.50" WILL
CREATE THE POTENTIAL FOR SOME HEAVY DOWNPOURS IN ANY TRW THAT DOES
DEVELOP...ESPECIALLY THURS/FRI.
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
THROUGH 06Z SUNDAY...VFR COND THRU MUCH OF FORECAST PERIOD. EXPECTING
MID CLD COVER AROUND BKN100-150 TO TRANSLATE DOWN TO BKN035-080
THIS AFTNOON AS WX SYSTEM APPROACHES. MSS/SLK WILL SEE MVFR COND
WITH CEILINGS DOWN NEAR BKN030 AND -RW DRIVING DOWN TO 5-6SM AT
TIMES BY 00Z SUN. AFT MIDDAY...VCSH/-SHRA POSSIBLE FOR ALL AREAS.
WINDS GENERALLY RANGING FROM SE TO SW 5-10KTS.
OUTLOOK 06Z SUNDAY THROUGH WEDNESDAY... MAINLY VFR CONDITIONS WL
PREVAIL THRU THE TIME PERIOD WITH THE EXCEPTION OF BRIEF MVFR/IFR
IN THE HEAVIER SHOWERS/STORMS. BEST CHCS FOR STORMS WL BE DURING
THE AFTERNOON AND EARLY EVENING HRS THRU TUESDAY. IN
ADDITION...SOME PATCHY EARLY MORNING FOG/BR WITH MVFR/IFR WL BE
POSSIBLE IF ANY TAF SITE RECIEVES HEAVY RAINFALL FROM CONVECTION
DURING THE DAYTIME. EXPECT MAINLY SOUTHERLY WINDS THRU THE PERIOD.
&&
.EQUIPMENT...
OBSERVATIONS FROM RUTLAND-SOUTHERN VERMONT REGIONAL AIRPORT
(KRUT) REMAIN UNAVAILABLE DUE TO A TELEPHONE COMMS LINE ISSUE. THE
FAA AOCC IS AWARE OF THE ISSUE...BUT THERE IS NO ESTIMATE AVAILABLE
AT THIS TIME AS TO WHEN THIS COMMS OUTAGE WILL BE FIXED.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...SISSON
NEAR TERM...LAHIFF
SHORT TERM...SISSON
LONG TERM...JN
AVIATION...JN/LOCONTO
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
135 AM EDT SAT JUN 22 2013
.SYNOPSIS...
HIGH PRESSURE ANCHORED OFF THE ATLANTIC COAST WILL KEEP THE NORTH
COUNTRY DRY TODAY WITH PARTLY TO MOSTLY SUNNY SKIES THIS AFTERNOON
AND TEMPERATURES IN THE MID 70S TO LOWER 80S. A WARM FRONT WILL
MOVE SLOWLY THROUGH THE AREA ON SATURDAY WITH SOME SHOWERS AND A
SLIGHT CHANCE OF A THUNDERSTORM WITH TEMPERATURES AGAIN RANGING
THROUGH THE 70S NORTHEAST TO THE LOWER 80S SOUTHWEST. EVEN WARMER
AND MORE HUMID CONDITIONS ARE EXPECTED SUNDAY INTO NEXT WEEK...WITH
DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS...MAINLY DURING THE
AFTERNOON AND EVENING HOURS.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1250 AM EDT SATURDAY...INHERITED FORECAST IN GOOD SHAPE
WITH ONLY UPDATE NEEDED TO INCREASE SKY COVER AS CONVECTIVE DEBRIS
CLOUDS ARE FILLING INTO THE REGION. WITH INCREASED CLOUD COVER
TEMPS SHOULD HOLD FAIRLY STEADY FOR THE REMAINDER OF THE NIGHT IN
THE 50S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY NIGHT/...
AS OF 323 PM EDT FRIDAY...SATURDAY...MODERATE CONFIDENCE CONTINUES
THAT WE`LL SEE SOME SOME SHOWERS AND A SLIGHT CHANCE OF A
THUNDERSTORM AS THE DECAYING MCV AND SHORT WAVE TROF MOVES ACROSS
THE REGION DURING MIDDAY INTO THE EARLY EVENING. MODEL GUIDANCE
HAS BEEN STRUGGLING WITH THE PLACEMENT OF THIS FEATURE WITH THE
GFS MORE WIDESPREAD AND FURTHER SOUTH AND THE NAM FURTHER NORTH.
HAVE PLAYED IT MORE TOWARD THE GFS/MAV SOLUTION AS RAP ANALYSIS
SHOWS SIGNIFICANT MCV HAS FORMED. SO HIGHER POPS THAN WHAT THE NAM
MOS SUGGESTS AND SLIGHT COOLER TEMPERATURES. HAVE STAYED MAINLY
NEAR 80 WITH COOLER TEMPS NORTHEAST AND WARMER SOUTHWEST. WHERE
CLOUDS/SHOWERS HANG ON IT COULD BE 5 DEGREES COOLER AND WHERE THEY
DISSIPATE 5 DEGREES WARMER.
IN THE ABSENCE OF ANY LARGE SCALE FORCING...ANY CONVECTIVE
ACTIVITY WILL DISSIPATE GOING INTO THE EVENING AND OVERNIGHT
HOURS SAT NIGHT WITH LOWS MAINLY IN THE 60S.
ON SUNDAY...MORE TYPICAL ISOLATED TO SCATTERED AIRMASS TYPE PULSE
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE AGAIN ON SUNDAY MAINLY
IN THE MID TO LATE AFTERNOON/EVENING WITH ACTIVITY SETTLING DOWN
OVERNIGHT SUNDAY NIGHT. CAPE VALUES NOT ALL THAT IMPRESSIVE (BELOW
100 J/KG) WITH GFS SUGGESTING A CAPPING SUBSIDENCE INVERSION MAY
BE IN PLACE SO KEPT A MINIMAL CHANCE POPS IN THE FORECAST. IT
SHOULD BE CONSIDERABLY WARMER AND MORE HUMID AIR PUSHES IN AS THE
WARM FRONT LIFTS NORTHEAST SUNDAY WITH HIGHS IN THE 80S.
SUNDAY NIGHT SHOULD BE VERY MILD WITH READINGS IN THE 60S PERHAPS NEAR 70
AT BTV WITH WARM AND HUMID AIR FIRMLY ENTRENCHED.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 350 PM EDT FRIDAY...LARGE SCALE PATTERN WL CONTINUE TO
SUPPORT MID/UPPER LVL RIDGE ACRS THE SE CONUS WITH FAST WESTERLY
FLW ALOFT NEAR THE INTERNATIONAL BORDER THRU EARLY NEXT WEEK. BY
MID TO LATE NEXT WEEK ALL GUIDANCE SUGGESTS A PATTERN CHANGE WITH
DEVELOPMENT OF FULL LATITUDE TROF ACRS THE GREAT LAKES/EASTERN
CONUS AND LARGE RIDGE OVER THE INTER-MOUNTAIN WEST. THIS WL RESULT
IN MUCH ABOVE NORMAL TEMPS FOR MONDAY/TUESDAY WITH CHCS FOR
AFTN/EVENING SHOWERS/STORMS...WITH A TREND TWD COOLER AND WETTER
CONDITIONS BY LATE NEXT WEEK...AS TROF DEVELOPS AND SFC LOW PRES
IMPACTS OUR FA. PROGGED 85H TEMPS NEAR 16C AND 925MB TEMPS BTWN
20-22C ON MONDAY/TUESDAY...SUPPORTS HIGHS WELL INTO THE 80S WITH
EVEN A FEW LOWER 90S POSSIBLE IN THE WARMER VALLEY LOCATIONS. IN
ADDITION...PROGGED SFC DWPTS ARE EXPECTED TO BE IN THE MID/UPPER
60S...CREATING VERY MUGGY CONDITIONS...ESPECIALLY ON MONDAY. THIS
HEAT/HUMIDITY WL HELP TO PRODUCE SOME MODEST CAPE
VALUES...COMBINED WITH EMBEDDED 5H VORTS WL HELP IN THE
DEVELOPMENT OF AFTN/EVENING SHOWERS/STORMS. WL CONT TO MENTION CHC
POPS ATTM...WITH MAIN FOCUS DURING THE PEAK HEATING HRS. ANY
STORMS THAT DUE DEVELOP WL HAVE THE POTENTIAL TO PRODUCE LOCALIZED
HEAVY DOWNPOURS WITH PW VALUES BTWN 1.50 AND 1.75". BETTER
DYNAMICS AND MOISTURE ARRIVES BY LATE NEXT WK...AS MID/UPPER LVL
TROF DEVELOPS OVER THE GREAT LAKES. STILL SOME UNCERTAINTY OF
MAGNITUDE AND POSITION OF SYSTEM ALONG WITH AVAILABLE
MOISTURE...THEREFORE WL MENTION CHC POPS ATTM...WITH TEMPS
DROPPING BACK TO NEAR NORMAL. EXPECT ABOVE NORMAL LOW TEMPS THRU
THE PERIOD...GIVEN AMOUNT OF BL MOISTURE AND POTENTIAL FOR
CLOUDS/PRECIP...MAINLY IN THE U50S MTNS TO NEAR 70F CPV/SLV.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
THROUGH 06Z SUNDAY...VFR COND THRU MUCH OF FORECAST PERIOD. EXPECTING
MID CLD COVER AROUND BKN100-150 TO TRANSLATE DOWN TO BKN035-080
THIS AFTNOON AS WX SYSTEM APPROACHES. MSS/SLK WILL SEE MVFR COND
WITH CEILINGS DOWN NEAR BKN030 AND -RW DRIVING DOWN TO 5-6SM AT
TIMES BY 00Z SUN. AFT MIDDAY...VCSH/-SHRA POSSIBLE FOR ALL AREAS.
WINDS GENERALLY RANGING FROM SE TO SW 5-10KTS.
OUTLOOK 06Z SUNDAY THROUGH WEDNESDAY... MAINLY VFR CONDITIONS WL
PREVAIL THRU THE TIME PERIOD WITH THE EXCEPTION OF BRIEF MVFR/IFR
IN THE HEAVIER SHOWERS/STORMS. BEST CHCS FOR STORMS WL BE DURING
THE AFTERNOON AND EARLY EVENING HRS THRU TUESDAY. IN
ADDITION...SOME PATCHY EARLY MORNING FOG/BR WITH MVFR/IFR WL BE
POSSIBLE IF ANY TAF SITE RECIEVES HEAVY RAINFALL FROM CONVECTION
DURING THE DAYTIME. EXPECT MAINLY SOUTHERLY WINDS THRU THE PERIOD.
&&
.EQUIPMENT...
OBSERVATIONS FROM RUTLAND-SOUTHERN VERMONT REGIONAL AIRPORT
(KRUT) REMAIN UNAVAILABLE DUE TO A TELEPHONE COMMS LINE ISSUE. THE
FAA AOCC IS AWARE OF THE ISSUE...BUT THERE IS NO ESTIMATE AVAILABLE
AT THIS TIME AS TO WHEN THIS COMMS OUTAGE WILL BE FIXED.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...SISSON
NEAR TERM...LAHIFF
SHORT TERM...SISSON
LONG TERM...TABER
AVIATION...JN/LOCONTO
EQUIPMENT...BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1252 AM EDT SAT JUN 22 2013
.SYNOPSIS...
HIGH PRESSURE ANCHORED OFF THE ATLANTIC COAST WILL KEEP THE NORTH
COUNTRY DRY TODAY WITH PARTLY TO MOSTLY SUNNY SKIES THIS AFTERNOON
AND TEMPERATURES IN THE MID 70S TO LOWER 80S. A WARM FRONT WILL
MOVE SLOWLY THROUGH THE AREA ON SATURDAY WITH SOME SHOWERS AND A
SLIGHT CHANCE OF A THUNDERSTORM WITH TEMPERATURES AGAIN RANGING
THROUGH THE 70S NORTHEAST TO THE LOWER 80S SOUTHWEST. EVEN WARMER
AND MORE HUMID CONDITIONS ARE EXPECTED SUNDAY INTO NEXT WEEK...WITH
DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS...MAINLY DURING THE
AFTERNOON AND EVENING HOURS.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1250 AM EDT SATURDAY...INHERITED FORECAST IN GOOD SHAPE
WITH ONLY UPDATE NEEDED TO INCREASE SKY COVER AS CONVECTIVE DEBRIS
CLOUDS ARE FILLING INTO THE REGION. WITH INCREASED CLOUD COVER
TEMPS SHOULD HOLD FAIRLY STEADY FOR THE REMAINDER OF THE NIGHT IN
THE 50S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY NIGHT/...
AS OF 323 PM EDT FRIDAY...SATURDAY...MODERATE CONFIDENCE CONTINUES
THAT WE`LL SEE SOME SOME SHOWERS AND A SLIGHT CHANCE OF A
THUNDERSTORM AS THE DECAYING MCV AND SHORT WAVE TROF MOVES ACROSS
THE REGION DURING MIDDAY INTO THE EARLY EVENING. MODEL GUIDANCE
HAS BEEN STRUGGLING WITH THE PLACEMENT OF THIS FEATURE WITH THE
GFS MORE WIDESPREAD AND FURTHER SOUTH AND THE NAM FURTHER NORTH.
HAVE PLAYED IT MORE TOWARD THE GFS/MAV SOLUTION AS RAP ANALYSIS
SHOWS SIGNIFICANT MCV HAS FORMED. SO HIGHER POPS THAN WHAT THE NAM
MOS SUGGESTS AND SLIGHT COOLER TEMPERATURES. HAVE STAYED MAINLY
NEAR 80 WITH COOLER TEMPS NORTHEAST AND WARMER SOUTHWEST. WHERE
CLOUDS/SHOWERS HANG ON IT COULD BE 5 DEGREES COOLER AND WHERE THEY
DISSIPATE 5 DEGREES WARMER.
IN THE ABSENCE OF ANY LARGE SCALE FORCING...ANY CONVECTIVE
ACTIVITY WILL DISSIPATE GOING INTO THE EVENING AND OVERNIGHT
HOURS SAT NIGHT WITH LOWS MAINLY IN THE 60S.
ON SUNDAY...MORE TYPICAL ISOLATED TO SCATTERED AIRMASS TYPE PULSE
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE AGAIN ON SUNDAY MAINLY
IN THE MID TO LATE AFTERNOON/EVENING WITH ACTIVITY SETTLING DOWN
OVERNIGHT SUNDAY NIGHT. CAPE VALUES NOT ALL THAT IMPRESSIVE (BELOW
100 J/KG) WITH GFS SUGGESTING A CAPPING SUBSIDENCE INVERSION MAY
BE IN PLACE SO KEPT A MINIMAL CHANCE POPS IN THE FORECAST. IT
SHOULD BE CONSIDERABLY WARMER AND MORE HUMID AIR PUSHES IN AS THE
WARM FRONT LIFTS NORTHEAST SUNDAY WITH HIGHS IN THE 80S.
SUNDAY NIGHT SHOULD BE VERY MILD WITH READINGS IN THE 60S PERHAPS NEAR 70
AT BTV WITH WARM AND HUMID AIR FIRMLY ENTRENCHED.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 350 PM EDT FRIDAY...LARGE SCALE PATTERN WL CONTINUE TO
SUPPORT MID/UPPER LVL RIDGE ACRS THE SE CONUS WITH FAST WESTERLY
FLW ALOFT NEAR THE INTERNATIONAL BORDER THRU EARLY NEXT WEEK. BY
MID TO LATE NEXT WEEK ALL GUIDANCE SUGGESTS A PATTERN CHANGE WITH
DEVELOPMENT OF FULL LATITUDE TROF ACRS THE GREAT LAKES/EASTERN
CONUS AND LARGE RIDGE OVER THE INTER-MOUNTAIN WEST. THIS WL RESULT
IN MUCH ABOVE NORMAL TEMPS FOR MONDAY/TUESDAY WITH CHCS FOR
AFTN/EVENING SHOWERS/STORMS...WITH A TREND TWD COOLER AND WETTER
CONDITIONS BY LATE NEXT WEEK...AS TROF DEVELOPS AND SFC LOW PRES
IMPACTS OUR FA. PROGGED 85H TEMPS NEAR 16C AND 925MB TEMPS BTWN
20-22C ON MONDAY/TUESDAY...SUPPORTS HIGHS WELL INTO THE 80S WITH
EVEN A FEW LOWER 90S POSSIBLE IN THE WARMER VALLEY LOCATIONS. IN
ADDITION...PROGGED SFC DWPTS ARE EXPECTED TO BE IN THE MID/UPPER
60S...CREATING VERY MUGGY CONDITIONS...ESPECIALLY ON MONDAY. THIS
HEAT/HUMIDITY WL HELP TO PRODUCE SOME MODEST CAPE
VALUES...COMBINED WITH EMBEDDED 5H VORTS WL HELP IN THE
DEVELOPMENT OF AFTN/EVENING SHOWERS/STORMS. WL CONT TO MENTION CHC
POPS ATTM...WITH MAIN FOCUS DURING THE PEAK HEATING HRS. ANY
STORMS THAT DUE DEVELOP WL HAVE THE POTENTIAL TO PRODUCE LOCALIZED
HEAVY DOWNPOURS WITH PW VALUES BTWN 1.50 AND 1.75". BETTER
DYNAMICS AND MOISTURE ARRIVES BY LATE NEXT WK...AS MID/UPPER LVL
TROF DEVELOPS OVER THE GREAT LAKES. STILL SOME UNCERTAINTY OF
MAGNITUDE AND POSITION OF SYSTEM ALONG WITH AVAILABLE
MOISTURE...THEREFORE WL MENTION CHC POPS ATTM...WITH TEMPS
DROPPING BACK TO NEAR NORMAL. EXPECT ABOVE NORMAL LOW TEMPS THRU
THE PERIOD...GIVEN AMOUNT OF BL MOISTURE AND POTENTIAL FOR
CLOUDS/PRECIP...MAINLY IN THE U50S MTNS TO NEAR 70F CPV/SLV.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
THROUGH 00Z SUNDAY...MAINLY VFR THROUGH THE OVERNIGHT HOURS
THOUGH MID TO HIGH-LEVEL CLOUDINESS WILL BE ON THE INCREASE
PARTICULARLY AFTER MIDNIGHT. WINDS WILL BE LIGHT AND VARIABLE
UNDER BROAD SFC RIDGING. FOR SATURDAY...EXPECTING SHOWERS AND
THUNDERSTORMS AND DEVELOPING SOUTHEASTWARD WITH TIME. EXACT TIMING
ON THE ONSET OF PRECIPITATION IS DIFFICULT IT IS DEPENDENT ON WHAT
EVOLVES WITH THE ONGOING CONVECTION ACROSS THE NORTHERN
PLAINS/GREAT LAKES REGION TONIGHT. HOWEVER BASED ON PRESENT
INDICATIONS THIS APPEARS TO BE IN THE 13-18Z TIMEFRAME. FOR NOW
HAVE TREATED WITH VCSH DURING THAT PERIOD OF TIME. POTENTIAL FOR
MVFR VISIBILITIES (BRIEF IFR VISIBILITIES POSSIBLE IN
STEADIER/HEAVIER RAIN). WINDS WILL BE SOUTH/SOUTHWEST UNDER
10KTS...EXCEPT LIGHT/VARIABLE AT MSS.
OUTLOOK 00Z SUNDAY THROUGH TUESDAY... MAINLY VFR CONDITIONS WL PREVAIL
THRU THE TIME PERIOD WITH THE EXCEPTION OF BRIEF MVFR/IFR IN THE
HEAVIER SHOWERS/STORMS. BEST CHCS FOR STORMS WL BE DURING THE
AFTERNOON AND EARLY EVENING HRS THRU TUESDAY. IN ADDITION...SOME
PATCHY EARLY MORNING FOG/BR WITH MVFR/IFR WL BE POSSIBLE IF ANY
TAF SITE RECIEVES HEAVY RAINFALL FROM CONVECTION DURING THE
DAYTIME. EXPECT MAINLY SOUTHERLY WINDS THRU THE PERIOD.
&&
.EQUIPMENT...
OBSERVATIONS FROM RUTLAND-SOUTHERN VERMONT REGIONAL AIRPORT
(KRUT) REMAIN UNAVAILABLE DUE TO A TELEPHONE COMMS LINE ISSUE. THE
FAA AOCC IS AWARE OF THE ISSUE...BUT THERE IS NO ESTIMATE AVAILABLE
AT THIS TIME AS TO WHEN THIS COMMS OUTAGE WILL BE FIXED.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...SISSON
NEAR TERM...LAHIFF
SHORT TERM...SISSON
LONG TERM...TABER
AVIATION...TABER/LOCONTO
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
145 AM EDT SAT JUN 22 2013
.SYNOPSIS...
A SLOW-MOVING FRONT JUST OFFSHORE...WILL DRIFT WEST AND ONSHORE LATE
TONIGHT AND SATURDAY...INCREASING THE POTENTIAL FOR SHOWERS AND
THUNDERSTORMS. TYPICAL SUMMERTIME WEATHER IS EXPECTED TO RETURN NEXT
WEEK WITH BERMUDA HIGH PRESSURE...THE PIEDMONT TROUGH AND THE DAILY
SEA BREEZE...BECOMING THE DOMINANT SURFACE FEATURES.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 1045 PM FRIDAY...AS WE MOVE FURTHER INTO THE PRE-DAWN
SATURDAY HOURS...CONVECTION ALONG AND AHEAD OF THE COASTAL FRONT
JUST OFFSHORE...WILL OVERSPREAD THE COASTAL AREAS OF THE ILM CWA.
AS SEEN WITH LOCAL AND ADJACENT 88DS...THE CONVECTION FALLS APART
THE FURTHER INLAND IT TRACKS DUE TO THE DRIER AIR MASS IT
ENCOUNTERS. WITH TIME AND AFTER THIS PERIOD...THE AIRMASS OVER
INLAND LOCATIONS WILL BECOME SATURATED AND PRIMED FOR EXTENDED
CONVECTION. TIMING ISSUES CONTINUE FOR THE SPREADING INLAND OF
THE 50-70 POPS OVERNIGHT INTO SATURDAY. LATEST SREF PROBS FOR
MEASURE-ABLE PCPN ILLUSTRATES DRAMATICALLY INCREASING POPS TOWARD
DAYBREAK ACROSS THE MAJORITY OF THE ILM CWA. MIN TEMP GUIDANCE
EARLIER TWEAKED WILL REMAIN AS IS. THE KLTX VWP AND 00Z SOUNDINGS
FROM CHS AND MHX INDICATE AN ONSHORE FLOW SFC THRU AT LEAST 20K
FEET...INDICATIVE OF A SUBTROPICAL/TROPICAL AIR MASS BEING
ADVECTED ACROSS THE FA. 00Z PWS HAVE ALSO INCREASED...UP TO 1.87
INCHES AT MHX AND 1.68 INCHES AT CHS. PWS WILL LIKELY FURTHER RISE
OVERNIGHT...AND THUS WILL CONTINUE TO HIGHLIGHT PONDING OF WATER
POSSIBLE FROM HEAVY DOWNPOURS TONIGHT INTO SATURDAY IN THE HWO.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...THE MAIN FORECAST CHALLENGE WILL BE CENTERED
AROUND POPS MAINLY FOR SATURDAY AS A SEEMINGLY EVER PRESENT FRONT
FINALLY MAKES A MOVE INLAND. I HAVE TRENDED TOWARD THE MORE
AGGRESSIVE MET/NAM GUIDANCE FOR POPS WHICH WARRANT AN INCREASE FOR
SATURDAY`S VALUES. THIS CALLS FOR AN INCREASE IN CLOUD COVER AS
WELL WHILE LEANING TOWARD THE LOWER NUMBERS ALONG THE COAST FOR
HIGHS. AS FOR SATURDAY NIGHT AND SUNDAY THE FRONT WILL BECOME
ABSORBED INTO THE SOUTHERLY SYNOPTIC FLOW AND POPS WILL BE
ADDRESSED ON A MORE TYPICAL FASHION OF HIGHER VALUES BEING IN THE
AFTERNOON AND EARLY EVENING HOURS.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 3 PM FRIDAY...UPPER LEVEL HIGH PRESSURE JUST OFF THE
CAROLINA COAST MONDAY AND TUESDAY. THERE MAY BE A WEAKNESS ON ITS
WESTERN PERIPHERY DUE TO LEFTOVER REMNANTS OF THE UPPER LOW OVER
THE WRN PART OF THE CAROLINAS CURRENTLY. AT THE SURFACE HIGH
PRESSURE TO COVER A BROAD EXPANSE OF THE WEST ATLANTIC. THE
ORIENTATION OF THE HIGH WILL BE WEST TO EAST ELONGATED...WHICH IS
NOT OPTIMAL FOR MOISTURE ADVECTION INTO THE REGION. EVEN SO A
FAIRLY SEASONABLE AND DIURNAL COVERAGE OF CONVECTION SEEMS LIKELY.
WED AND THURS TRANSITIONAL DAYS ALOFT WITH RIDGING BECOMING BROAD
ACROSS THE NATIONS MIDSECTION EARLY ON FOLLOWED BY LARGE INCREASE
IN AMPLITUDE OVER WRN STATES ON THURSDAY. THE TROUGHINESS
DOWNSTREAM OVER THE EAST WILL BE CLOSED OFF QUICKLY PREVENTING
MUCH AMPLITUDE INCREASE/LOCAL EFFECTS. INSTEAD A BROAD AND WEAK
NORTHWESTERLY FLOW DEVELOPS. SURFACE PIEDMONT TROUGHINESS DEVELOPS
AS WELL. IN THE END THE FORMER MAY ACT TO SLIGHTLY INHIBIT
CONVECTION WHILE THE LATTER TRIES TO INCREASE IT. END RESULT MAY
MEAN LITTLE SIGNIFICANT CHANGES IN RAIN CHANCES THROUGH MOST OF
THE PERIOD. ON FRIDAY TROUGHINESS APPEARS TO INCREASE IN AMPLITUDE
OVER THE EASTERN U.S.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 06Z...PERIODS OF MVFR/IFR EXPECTED DUE TO ISOLATED TO
SCATTERED SHOWERS/THUNDERSTORMS...PERIODS OF LOWERED CIGS AND PATCHY
FOG THROUGH THE VALID PERIOD. OTHERWISE VFR.
TRICKY FORECAST CONTINUES FOR THE TAF PERIOD AS A NEARLY STALLED
FRONT OFFSHORE CONTINUES TO SLOWLY MOVE WEST TOWARD THE AREA.
LATEST RADAR IMAGERY DEPICTS SHOWERS AFFECTING MAINLY THE COASTAL
SITES. ANTICIPATE TREND WILL CONTINUE THROUGH THE VALID PERIOD...
WITH HEAVIER RAINFALL EXPECTED TO PUSH TO THE INLAND SITES BY THE
MORNING HOURS. PERIODS OF HEAVY RAINFALL...ALONG WITH INTERMITTENT
PERIODS OF LOWERED CIGS...ARE EXPECTED TO REDUCE CONDITIONS TO
MVFR/IFR THROUGHOUT THE VALID PERIOD. THUNDERSTORM CHANCES WILL
INCREASE ON SATURDAY AS WELL...THOUGH GIVEN UNCERTAINTY HAVE OPTED
TO KEEP VCTS ATTM. AS FOR WINDS...NORTHEAST WINDS 5 TO 8 KTS THROUGH
LATE MORNING ON SATURDAY WILL GRADUALLY BECOME EAST-SOUTHEAST ALONG
THE COAST BY AFTERNOON WITH SUSTAINED WINDS AOB 8 KTS. INTO THE
EVENING HOURS...TSRA CHANCES WILL DIMINISH WITH ISOLATED TO
SCATTERED SHOWERS CONTINUING AND LIGHT EAST-SOUTHEAST WINDS.
EXTENDED OUTLOOK...ISOLATED TO SCATTERED SHOWERS THROUGH WEDNESDAY
AS A STALLED FRONT LINGERS NEAR THE COAST. BETTER CHANCE OF
PRECIPITATION WILL BE IN THE AFTERNOON HOURS WITH LOCALIZED PERIODS
OF MVFR/IFR POSSIBLE.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1045 PM FRIDAY...THE APPROACH AND EVENTUAL PASSAGE OF THE
COASTAL FRONT ONSHORE WILL GOVERN THE WINDS ACROSS THE ILM WATERS.
LOOKING AT A NE-E WIND AHEAD OF THE FRONT...SE-S WIND AFTER ITS
PASSAGE. SFC PG HAVING SOMEWHAT RELAXED AHEAD OF THE FRONT...
RESULTING WITH WIND SPEEDS AROUND 10 KT. HRRR AND NAM INDICATE A
TIGHTENING OF THE GRADIENT AFTER ITS PASSAGE...WITH WIND SPEEDS
AROUND 15 KT...POSSIBLY WITH GUSTS UP TO 20 KT. SIGNIFICANT SEAS
EARLY ON WILL INITIALLY DROP TO 2 TO 3 FT THRUOUT THE ILM
WATERS...THEN INCREASE TO 3 TO 4 FT ALONG AND AFTER THE COASTAL
FRONT PUSHES ONSHORE. THE NAM AND HRRR INDICATE THE FRONT TO PUSH
ONSHORE FROM CAPE FEAR NORTH AROUND DAYBREAK...AND THE REMAINING
WATERS SOUTH OF THE CAPE DURING DAYLIGHT SATURDAY.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...MAIN FORECAST CHALLENGE FOR THE MARINE
COMMUNITY WILL OCCUR EARLY IN THE PERIOD AS A FRONT THAT HAS BEEN
LINGERING OFF THE COAST MAKES A MOVE INLAND. WIND DIRECTION WILL BE
A LOW CONFIDENCE EVENT FOR SATURDAY UNTIL THE SYNOPTIC SOUTHEASTERLY
FLOW BECOMES THE DOMINANT FEATURE LATE SATURDAY. FOR NOW THE COASTAL
AREAS WILL SEE A WEST TO NORTHWEST FLOW EARLY WITH A SOUTHEASTERLY
FLOW ACROSS THE OUTER WATERS. ALL AREAS SHOULD SEE SOUTHEASTERLY
WINDS LATE SATURDAY. FOR SUNDAY A TYPICAL SUMMERTIME PATTERN OF
SOUTHERLY WINDS WILL PREVAIL. FOR THE MOST PART WIND SPEEDS WILL
REMAIN MORE REPRESENTATIVE OF SUMMER WITH 10-15 KNOTS PROBABLY
LEANING MORE TOWARD THE LOWER END OF THE RANGE. WAVEWATCH SEAS
REMAIN IN A 2-4 FOOT RANGE THROUGH THE PERIOD.
LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 3 PM FRIDAY...HIGH PRESSURE ACROSS THE WEST ALTAIC THE ENTIRE
TIME. THIS HIGH WILL EXTEND A RIDGE AXIS INTO THE CAROLINAS THROUGH
THE PERIOD THAT MAY VACILLATE IN BOTH STRENGTH AND LOCATION AT
TIMES. END RESULT WILL BE SMALL VARIATIONS IN WIND DIRECTION BETWEEN
SOUTH AND SOUTHWEST. WIND SPEED WILL SHOW LITTLE ENOUGH CHANGE THAT
A FORECAST OF ABOUT 10 KTS WILL HOLD FOR MOST OF THE TIME. WNA
GUIDANCE SHOWS A MINOR EASTERLY SWELL COMBINING WITH THE WIND WAVES
ON TUESDAY. OVERALL SEAS FORECAST HOWEVER TO REMAIN FAIRLY
UNCHANGING AT A GENERAL 2 TO 4 FT...HIGHEST OFFSHORE.
&&
.TIDES/COASTAL FLOODING...
AS OF 11 PM FRIDAY...HIGH TIDE AND ASSOCIATED HIGHEST GAGE
READINGS HAVE COME AND BY NOW ACROSS THE BEACHES AND NOW ACROSS
ALONG THE CAPE FEAR RIVER. MYRTLE BEACH SPRINGMAID PIER ECLIPSED
7.05 FT MLLW...WRIGHTSVILLE BEACH JOHNNY MERCER PIER AT 5.7 FT
MLLW...AND THE WILMINGTON GAGE IN THE CAPE FEAR RIVER AROUND 5.8
FT MLLW. THE NEXT HIGH TIDE CYCLES SUSCEPTIBLE TO MINOR COASTAL
FLOODING WILL OCCUR ON SATURDAY...SUNDAY AND MONDAY DURING THE MID
TO LATE EVENING HOURS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...SHK
LONG TERM...MBB
AVIATION...SGL/RJD
TIDES/COASTAL FLOODING...DCH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
953 PM CDT SUN JUN 23 2013
.UPDATE...
ISSUED AT 952 PM CDT SUN JUN 23 2013
WANING CONVECTION OVER NORTHERN FOSTER COUNTY SHOULD QUICKLY
DIMINISH IN THE NEXT HOUR. WILL KEEP A CHANCE POP HERE FOR THE
NEXT HOUR. OTHERWISE...ISOLATED SHOWERS FROM SOUTHERN SASKATCHEWAN
INTO NORTHWEST NORTH DAKOTA CONTINUE TO QUICKLY DIMINISH. WILL NOT
MENTION POPS HERE TONIGHT. OTHERWISE...CURRENT FORECAST IS IN GOOD
SHAPE. DID ADJUST CLOUD COVER LOWER FOR MOST AREAS THIS EVENING
AND WAS A LITTLE SLOWER TO INCREASE CLOUD COVER AFTER MIDNIGHT IN
THE WEST. LATEST 01Z HRRR IS BRINGING SOME LIGHT QPF INTO THE FAR
SOUTHWEST BETWEEN 11Z-12Z MONDAY...SO WILL KEEP A SLIGHT CHANCE OF
CONVECTION IN THE FAR SOUTHWEST TOWARD MORNING.
UPDATE ISSUED AT 703 PM CDT SUN JUN 23 2013
MAIN ISSUE WITH THE EARLY EVENING UPDATE IS CURRENT SHOWER AND
THUNDERSTORM ACTIVITY. CURRENTLY SHOWER AND THUNDERSTORMS WERE
LOCATED FROM JUST NORTH OF GARRISON...TO MINOT...AND THEN
NORTHEAST TO ROLETTE COUNTY. WITH A FEW STRAY SHOWERS EXTENDING
BACK TO NEAR CROSBY. ACTIVITY HAS SHOWN A DECREASE IN INTENSITY
IN THE PAST TWO HOURS. HAVE ADJUSTED POPS A BIT LOWER AND
DECREASED AREAL COVERAGE. EXPECT ACTIVITY TO CONTINUE TO DECREASE
OVER THE NEXT FEW HOURS...AND DISSIPATE COMPLETELY BY AROUND 10 PM.
OTHERWISE NO SIGNIFICANT CHANGES TO THE CURRENT FORECAST.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 345 PM CDT SUN JUN 23 2013
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE SCATTERED
STRONG THUNDERSTORMS NORTH THIS AFTERNOON/EARLY EVENING...FOLLOWED
BY ANOTHER CHANCE OF POSSIBLY STRONG TO SEVERE STORMS MONDAY
AFTERNOON.
CURRENTLY...UPPER LOW OVER CENTRAL SASKATCHEWAN WITH A STRONG
EMBEDDED IMPULSE ROTATING NORTHEAST THROUGH THE DEVILS LAKE BASIN
INTO NORTHEAST NORTH DAKOTA. STEEP LAPSE RATES WITH COLD AIR ALOFT
HAS TRIGGERED A FEW STRONGER STORMS NEAR THE INTERNATIONAL
BORDER. A FEW STRONGER STORMS ARE POSSIBLE AND PERHAPS PULSE
SEVERE WITH MUCAPE 1-2K J/KG. LACK OF SUPPORTIVE 0-6KM SHEAR WILL
LIMIT UPDRAFT LONGEVITY. STORMS ARE DIURNAL IN NATURE AND SHOULD
QUICKLY DISSIPATE INTO EARLY THIS EVENING AS THE NOCTURNAL
INVERSION DEVELOPS. BEFORE THIS HAPPENS...WILL NEED TO MONITOR FOR
POSSIBLE FUNNELS/LAND SPOUTS WITH THE NON-SUPERCELL TOR PARAMETER
ELEVATED OVER NORTHWEST NORTH DAKOTA.
MOSTLY CLEAR THE REMAINDER OF THIS EVENING IN THE WAKE OF THE
CURRENT CONVECTION. MODELS DEVELOP A LOW LEVEL JET LATER THIS
EVENING INTO THE OVERNIGHT ACROSS WESTERN SOUTH DAKOTA NOSING
INTO SOUTHWEST NORTH DAKOTA LATE AROUND OR AFTER 09Z. WILL
INTRODUCE SLIGHT CHANCES FOR THUNDER FAR SOUTHWEST 9-12Z GIVEN
THIS FORCING ALONG WITH INCREASING BOUNDARY LAYER MOISTURE. KEPT
SLIGHT CHANCE POPS GOING THROUGH THE MORNING HOURS WEST.
BOUNDARY LAYER MOISTURE CONTINUES TO ADVECT INTO THE REGION
THROUGHOUT THE DAY MONDAY THANKS TO STRONG MID LEVEL FLOW/MOISTURE
FETCH FROM THE SOUTHERN PLAINS INTO THE DAKOTAS WITH SFC DEWPOINT
TEMPS RISING INTO THE 60S AREA WIDE. THIS WILL CONTRIBUTE TO
INCREASING INSTABILITY WITH MUCAPES PROJECTED TO INCREASING TO
AROUND 2500 J/KG IN THE AFTERNOON AS SFC TEMPS WARM INTO THE
LOW/MID 80S. WHILE A CAPPING INVERSION LOOKS TO BE IN PLACE...A
POTENTIAL TRIGGER VIA A LEAD SHORT WAVE IMPULSE IS FORECAST TO
APPROACH THE DAKOTAS MONDAY AFTERNOON LEADING TO CONVECTIVE
INITIALIZATION. WILL MAINTAIN POPS AS IS FOR NOW DUE TO THE
UNCERTAINTY DURING THE AFTERNOON WHERE AND IF STORMS WILL
DEVELOP.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 345 PM CDT SUN JUN 23 2013
POTENTIAL FOR SEVERE THUNDERSTORMS CONTINUE MONDAY NIGHT AND
TUESDAY. SOUTHWEST FLOW ALOFT TRANSITIONS TO A WESTERLY FLOW
WEDNESDAY...THEN NORTHWEST AS RIDGING DEVELOPS OVER THE FOUR
CORNERS. HOWEVER THE RIDGE FLATTENS SATURDAY AS A SHORTWAVE ROLLS
THROUGH. THIS SHOULD BE TEMPORARY AS THE LONG TERM MODEL SUITE THEN
SHOWS A STRONGER AMPLIFICATION OF THE RIDGE TO COMMENCE ACROSS THE
INTERMOUNTAIN WEST JUST BEYOND THIS EXTENDED PERIOD.
FOR MONDAY NIGHT...WITH STRONG WARM/MOIST AIR ADVECTION IN
THE LOWER LEVELS COMBINED WITH A COUPLE OF SHORTWAVES TRANSVERSING
THROUGH VIA A SOUTHWEST FLOW ALOFT...THIS SHOULD BE ENOUGH TO
PROMOTE CONVECTION THROUGH THE NIGHT. SURFACE DEWPOINTS IN THE UPPER
60S TO AROUND 70 WILL YIELD MUGGY CONDITIONS AND VERY WARM OVERNIGHT
LOWS MONDAY NIGHT. THE STRONGEST SHORTWAVE SHIFTS THROUGH ON TUESDAY
AS A SURFACE COLD FRONT MOVES FROM WEST TO EAST. EXPECTING
THUNDERSTORMS LIKELY ALONG AND AHEAD OF THE FRONT. THE SCENARIO THAT
APPEARS MOST LIKELY IS THUNDERSTORMS WILL BE ONGOING FROM MONDAY
NIGHT AND CONTINUE FOR MOST OF TUESDAY INTO TUESDAY EVENING. THE
COLD FRONT SHOULD CLEAR THE JAMES RIVER VALLEY BY 06Z WEDNESDAY.
WEDNESDAY LOOKS MOSTLY DRY WITH THE EXCEPTION OF NORTH CENTRAL NORTH
DAKOTA WHERE A SHORTWAVE WILL MOVE THROUGH PRODUCING A SLIGHT CHC OF
SHOWERS/THUNDERSTORMS. RIDGING WEST OF NORTH DAKOTA AS MENTIONED
ABOVE WILL PROMOTE DRY WEATHER FOR THURSDAY/FRIDAY...THEN A CHANCE
FOR THUNDERSTORMS SATURDAY THROUGH SUNDAY WITH A SHORTWAVE MOVING
THROUGH.
WARMEST HIGH TEMPERATURES WILL BE TUESDAY WITH MID TO UPPER 80S
ALONG WITH HUMID CONDITIONS. DRIER AIR/LOWER DEWPOINTS CAN BE
EXPECTED FOR THE REST OF THE WEEK WITH HIGHS COOLING TO THE UPPER
70S NORTH AND LOWER 80S SOUTH THURSDAY THROUGH SATURDAY. OVERNIGHT
LOWS IN THE 60S TO NEAR 70 TUESDAY MORNING...THEN UPPER 50S FOR THE
REST OF THE LONG TERM PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 952 PM CDT SUN JUN 23 2013
VFR CONDITIONS ARE EXPECTED AT ALL TAF SITES THROUGH THE FORECAST
PERIOD. MAINLY CLEAR SKIES TONIGHT AND INCREASING MID AND HIGH
LEVEL CLOUDINESS ON MONDAY. LIGHT SOUTHWEST WINDS THIS EVENING
WILL SHIFT SOUTH...THEN INCREASE OUT OF THE SOUTHEAST ON MONDAY.
CONVECTION POSSIBLE IN THE WEST MONDAY 18Z-00Z BUT WILL HOLD OFF
ON BRINGING IT TO ANY SINGLE TAF SITE AT THIS TIME.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...NH
LONG TERM...KS
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
935 PM CDT SUN JUN 23 2013
.UPDATE...
ISSUED AT 934 PM CDT SUN JUN 23 2013
THE LAST OF THE SHOWERS DISSIPATING NOW MOVING INTO THE LANGDON-
DEVILS LAKE TO NEW ROCKORD AREAS. RE-DID THE POP GRIDDS TO ACCOUNT
FOR CURRENT AREA AND REMOVED ANY POPS FROM NW MN. NO OTHER CHANGES.
UPDATE ISSUED AT 628 PM CDT SUN JUN 23 2013
WATER VAPOR SHOWS SMALL IMPULSE MOVING INTO FAR SW MANITOBA FROM
SE SASK ATTM....THIS LEADING TO THE BIT MORE COVERAGE OF SHRA/TSRA
IN THAT REGION. SOME OF THIS WILL MOVE INTO DVL REGION AND ALONG
THE NRN BORDER REGION NEXT 1-3 HOURS BEFORE DARK. EXPECT ACTIVITY
TO WEAKEN AND DIMINISH BY 04-05Z AND UPDATED HOURLY POP GRIDDS TO
ACCOUNT FOR THAT. OTHERWISE NOTHING ELSE GOING ON IN MINNESOTA SO
TRIMMED POPS THERE TO ONLY THE FAR NORTH. WINDS WILL DIMINISH BY
02Z AND CU WILL CONTINUE TO DIMINISH LEADING TO A CLEAR SKY IN
MOST AREAS OVERNIGHT. LOWS LOOKED REASONABLE.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 313 PM CDT SUN JUN 23 2013
CONVECTION CHANCES CONTINUE TO BE THE PRIMARY FORECAST PROBLEM FOR
THE PERIOD.
WV LOOP SHOWS THE MAIN SHORTWAVE IS CURRENTLY IN THE PROCESS OF
LIFTING THROUGH THE CWA ON ITS WAY INTO CANADA. THE MAIN SFC LOW
IS ALREADY IN SOUTHERN MANITOBA...WITH ALL BUT THE FAR
NORTHEASTERN CWA SEEING WESTERLY WINDS ON THE SOUTH SIDE OF THE
LOW. THE RAIN BAND FROM THIS MORNING HAS LIFTING NORTH INTO
CANADA...AND SOME CLEARING HAS BEEN GOING ON ALTHOUGH WITH PRETTY
LOW CONVECTIVE TEMPS CU HAS REDEVELOPED RAPIDLY. THERE HAS BEEN A
DECREASE IN MOISTURE AS THE WEST WINDS BRING IN DRIER AIR...BUT
THERE IS STILL A DECENT AMOUNT OF HUMIDITY AND WITH SOME CLEARING
CAPE HAS REACHED AROUND 1000 J/KG ACROSS THE CENTRAL CWA. WHILE
THE BEST LIFT WILL BE QUICKLY MOVING OFF TO THE NORTH THIS
EVENING...THERE IS ENOUGH INSTABILITY HANGING AROUND THAT CANNOT
COMPLETELY RULE OUT THUNDERSTORM REDEVELOPMENT...AND THE RAP AND
HRRR SHOW SIGNS OF THIS ALTHOUGH STRENGTH DOES NOT SEEM IMPRESSIVE
AT THIS POINT. WILL KEEP SOME 30-60 POPS GOING MAINLY NORTH OF THE
HIGHWAY 2 CORRIDOR THROUGH EARLY EVENING BEFORE WE GO DRY AFTER
MIDNIGHT.
MONDAY SHOULD BE FAIRLY QUIET WITH WEAK UPPER RIDGING BETWEEN
SYSTEMS. WINDS WILL SHIFT BACK TO THE SOUTH AS A SFC TROUGH BEGINS
TO DEEPEN OVER THE ROCKIES/WESTERN PLAINS. 850MB TEMPS CLIMB BACK
UP TOWARDS THE UPPER TEENS C AND WITH PLENTY OF SUN WE SHOULD BE
ABLE TO CLIMB INTO THE MID 80S ACROSS MOST OF THE AREA. THE QUIET
CONDITIONS WILL BE SHORT LIVED AS MODELS SHOW SOME INDICATION OF A
WEAK SHORTWAVE MOVING IN MONDAY NIGHT. THINK THERE COULD BE SOME
STORMS MOVING IN FROM THE WEST MONDAY NIGHT...WITH THE MODELS
SHOWING SOME ELEVATED INSTABILITY LIFTING INTO THE CWA OVERNIGHT.
KEPT SOME POPS AROUND 30 PERCENT.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 313 PM CDT SUN JUN 23 2013
THINK THAT THE BETTER CHANCES FOR MORE SIGNIFICANT STORMS WILL BE
TUESDAY WHEN A FAIRLY STRONG SHORTWAVE TROUGH MOVES INTO THE
DAKOTAS. THE SFC TROUGH AXIS WILL MOVE INTO CENTRAL ND...WITH
SOUTHEASTERLY WINDS AHEAD OF IT AND GOOD LOW LEVEL CONVERGENCE.
INSTABILITY WILL DEPEND ON EXACTLY ANYTHING OVERNIGHT
EVOLVES...BUT THERE IS THE POSSIBILITY OF MORE THAN 2000 J/KG OF
CAPE. CONTINUED TO KEEP FAIRLY HIGH POPS FOR THUNDERSTORMS TUESDAY
INTO TUESDAY NIGHT...BUT IS A BIT EARLY FOR ANY SEVERE MENTION AT
THIS TIME.
SOME PRECIP MAY LINGER INTO WEDNESDAY MORNING...BUT OVERALL THERE
SHOULD BE A DRYING TREND AS THE UPPER SHORTWAVE PULLS OFF TOWARDS
THE GREAT LAKES. TEMPS SHOULD BE FAIRLY SEASONABLE IN THE LOW 80S.
WEDNESDAY NIGHT TO SATURDAY NIGHT...MODELS IN GOOD AGREEMENT WITH
RETROGRADING AND AMPLIFYING WESTERN CONUS RIDGE AND GREAT LAKES
TROUGH AT 500MB. AS A RESULT NW FLOW ACROSS THE NORTHERN PLAINS
WILL DEVELOP. THIS WILL MAKE FOR SEASONAL END OF JUNE TEMPERATURES
AND NEARLY CLIMO POPS AS THE TIMING OF ANY WEAK SHORT WAVES
FEATURE WILL NEED TO COINCIDE WITH PEAK HEATING TO INITIATE ANY
DIURNALLY DRIVEN CONVECTION AND OVERALL COVERAGE IS EXPECTED TO BE
LOW...THUS THE LOW POPS IN THE EXTENDED.
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1252 PM CDT SUN JUN 23 2013
LOW PRESSURE TRACKING ALMOST DUE NORTH ALONG RED RIVER NEAR HCO WITH
TROUGH AND EDGE OF RAIN NOW THRU TVF. EXPECT MVFR CIGS TO CONTINUE
TO IMPROVE WITH DRIER AIR MIXING IN ON WESTERLY GUSTS 20 TO
30KTS...SOME ISOLATED SHOWERS THIS AFTERNOON POSSIBLE...WITH VFR
CONDITIONS EXPECTED THIS EVENING AND OVERNIGHT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1252 PM CDT SUN JUN 23 2013
LOW PRESSURE TRACKING ALMOST DUE NORTH ALONG RED RIVER NEAR HCO WITH
TROUGH AND EDGE OF RAIN NOW THRU TVF. EXPECT MVFR CIGS TO CONTINUE
TO IMPROVE WITH DRIER AIR MIXING IN ON WESTERLY GUSTS 20 TO
30KTS...SOME ISOLATED SHOWERS THIS AFTERNOON POSSIBLE...WITH VFR
CONDITIONS EXPECTED THIS EVENING AND OVERNIGHT.
&&
.HYDROLOGY...
ISSUED AT 628 PM CDT SUN JUN 23 2013
NEW WARNINGS WERE DONE FOR THE BUFFALO RIVER AT SABIN AND DILWORTH
FOR MINOR FLOODING.
NEW WARNINGS ACROSS THE SOUTHERN VALLEY AT HARWOOD...WEST
FARGO... KINDRED...ABERCROMBIE WITH AN INCREASE OF FLOODING TO
MODERATE NOW EXPECTED AT WAHPETON AND FARGO AS THE AREA RIVERS
RESPOND TO LAST NIGHTS RAINFALL OF ONE TO TWO INCHES ON ALREADY
SATURATED SOILS. ALSO...MAPLETON WARNING WAS CANCELLED AS THE
RIVER FELL BELOW FLOOD STAGE EARLIER TODAY.
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...RIDDLE
SHORT TERM...JR
LONG TERM...JR/JK
AVIATION...RIDDLE
HYDROLOGY...WJB/JK
AREA FORECAST DISCUSSION
NWS BISMARCK ND
123 AM CDT SAT JUN 22 2013
.UPDATE...
ISSUED AT 122 AM CDT SAT JUN 22 2013
IN REGARDS TO CONVECTION THROUGH 12 UTC...WILL FOLLOW CLOSELY TO
THE 04 UTC HRRR AND RAP WHICH CONTINUE TO REGENERATE CONVECTION
ACROSS THE NORTHWEST AND NORTH CENTRAL IN THE RIGHT ENTRANCE
REGION OF AN UPPER LEVEL JET STREAK...WHICH MATCHES WELL WITH THE
LATEST RADAR TRENDS. OTHERWISE...THERE IS A SLIGHT CHANCE OF
THUNDERSTORMS ACROSS THE REMAINDER OF THE AREA AS THE
AFOREMENTIONED JET STREAK PROPAGATES SOUTHEAST THROUGH THE NIGHT.
DO BELIEVE THAT THE SEVERE THREAT IS QUICKLY DIMINISHING AS -10 TO
-30 HAIL CAPE VALUES HAVE FALLEN BELOW 200 J/KG AND DOWNDRAFT CAPE
VALUES BELOW 500 J/KG.
UPDATE ISSUED AT 952 PM CDT FRI JUN 21 2013
CLOUDS AND CONVECTION FARTHER SOUTH APPEARED TO BE A LIMITING
FACTOR FOR CONVECTION THIS EVENING. CURRENTLY THE NORTHWEST AND
FAR NORTH CENTRAL APPEAR TO BE THE MAIN AREAS OF FOCUS LATE THIS
EVENING ASSOCIATED WITH A WAVE LIFTING THROUGH NORTHEAST MONTANA.
HAVE ADJUSTED POPS ACCORDINGLY WITH HIGHEST POPS IN THESE AREAS
AND LOWER POPS ELSEWHERE. BUT WITH UNSTABLE AIRMASS REMAINING
ALOFT CANNOT PULL POPS COMPLETELY. CLOUD COVER MAY LIMIT FOG
DEVELOPMENT AS WELL...BUT WITH ABUNDANT MOISTURE AROUND AND NEAR
ZERO TEMP/DEWPOINT SPREADS ALREADY...WILL KEEP AREAS OF FOG IN THE
FORECAST ACROSS THE AREA TONIGHT INTO SATURDAY MORNING. NO CHANGES
TO TEMPERATURES...OTHER THAN POPULATE WITH LATEST SIGNIFICANT
WEATHER GRIDS.
UPDATE ISSUED AT 721 PM CDT FRI JUN 21 2013
QUICK UPDATE FOR EVENING POPS. NORTH A LOT OF CONVECTION OVER
WESTERN AND CENTRAL NORTH DAKOTA THIS EVENING. ONE AREA OF
CONVECTION FIRED IN NORTHERN BURLEIGH COUNTY...BUT HAS RECENTLY
DISSIPATED QUICKLY AS IT MOVED INTO A MORE STABLE ATMOSPHERE FROM
WELLS COUNTY NORTHWARD. WILL TONE DOWN POPS THIS EVENING TO MAINLY
SLIGHT CHANCE...EXCEPT ALONG THE FAR WEST WHERE CONVECTION HAS
DEVELOPED OVER EASTERN MONTANA. FOR NOW WILL LEAVE POP CHANCES
ALONE FOR THE OVERNIGHT PERIOD BUT WILL TAKE A CLOSER LOOK LATER
THIS EVENING. DID HAVE SOME STRONG WINDS OVER THE FAR SOUTHEAST
CWA DUE TO WAKE LOW FORMED FROM CONVECTION EARLIER OVER EASTERN
SOUTH DAKOTA. WINDS HERE HAVE ALSO DIMINISHED.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 254 PM CDT FRI JUN 21 2013
FORECAST HIGHLIGHTS WILL BE POSSIBLE SEVERE CONVECTION AND HEAVY
RAIN THROUGH SATURDAY.
CURRENTLY...UPPER LEVEL TROUGH OVER THE WESTERN CONUS AND A RIDGE
OVER THE MISSISSIPPI VALLEY RESULTS IN STRONG SOUTHWEST FLOW
ALOFT ACROSS THE DAKOTAS. STRONGEST CONVECTION RIGHT NOW IS OVER
SOUTH DAKOTA NEAR A STATIONARY FRONT/SFC TROUGH. EARLIER SEVERE
STORMS OVER NORTH DAKOTA QUICKLY WEAKENED AFTER 18Z AS FORCING
ALOFT DIMINISHED.
ADDITIONAL ENERGY MOVING THROUGH THE REGION IN SOUTHWEST FLOW
ALOFT STILL EXPECTED AND WILL MAINTAIN CURRENT THUNDERSTORM
PROBABILITIES AS IS FOR NOW. BEST CHANCE FOR SEVERE WEATHER WILL
CONTINUE TO BE FROM SOUTHWEST ND NORTHEAST INTO THE SOUTHERN
DEVILS LAKE BASIN WHERE THE BEST 0-6KM WIND SHEAR AND INSTABILITY
WILL BE CO LOCATED.
STORMS WILL EVENTUALLY DISSIPATE SOUTH TO NORTH TONIGHT AS FORCING
MOVES NORTH INTO CANADA. EXPECT REDEVELOPMENT OF LOW STRATUS AND
FOG WEST AND CENTRAL TONIGHT.
REDEVELOPMENT OF CONVECTION ON SATURDAY AS ADDITIONAL WAVES ADVECT
THROUGH THE NORTHERN PLAINS.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 254 PM CDT FRI JUN 21 2013
UPPER TROUGH WILL TRAVERSE ACROSS NORTH DAKOTA SUNDAY WITH MORE
SHOWERS AND THUNDERSTORMS. A BIT OF A BREAK SUNDAY NIGHT...BUT WITH
A PROGRESSIVE SOUTHWEST FLOW PERSISTING INTO TUESDAY NIGHT...EXPECT
A COUPLE MORE SHORTWAVES TO SHIFT THROUGH WITH ADDITIONAL CHANCES OF
FOR SHOWERS/THUNDERSTORMS. WEDNESDAY THROUGH FRIDAY...STILL
EXPECTING AN UPPER RIDGE TO DEVELOP OVER THE FOUR CORNERS DURING THE
PERIOD WITH THE RIDGE AXIS AMPLIFYING INTO SOUTHERN CANADA. A
COMPENSATORY NORTHWEST FLOW DEVELOPS INTO WESTERN AND CENTRAL NORTH
DAKOTA THURSDAY AND FRIDAY. THERE COULD BE A COUPLE OF RIDGE TOPPERS
SLIDING THROUGH RESULTING IN A CHANCE FOR SHOWERS AND THUNDERSTORMS
MAINLY IN EAST CENTRAL NORTH DAKOTA...WITH THE WEST REMAINING MORE
STABLE AND DRIER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY EVENING)
ISSUED AT 122 AM CDT SAT JUN 22 2013
MVFR TO IFR STRATUS AND FOG IS EXPECTED TO DEVELOP OVER MOST OF
WESTERN AND CENTRAL NORTH DAKOTA TONIGHT AND CONTINUE THROUGH
APPROXIMATELY 14-15 UTC SATURDAY. THE BEST CHANCES FOR
THUNDERSTORMS ON SATURDAY WILL BE ACROSS WESTERN AND NORTH CENTRAL NORTH
DAKOTA...INCLUDING KISN...KMOT AND KDIK WHERE THUNDERSTORMS MAY
CONTINUE TO REGENERATE MUCH OF THE DAY. OTHERWISE...BELIEVE THE
THREAT FOR STORMS WILL HOLD OFF UNTIL APPROXIMATELY 20-22 UTC FOR
KBIS AND AFTER 05 UTC AT KJMS SATURDAY NIGHT.
&&
.HYDROLOGY...
ISSUED AT 254 PM CDT FRI JUN 21 2013
WILL MAINTAIN THE FLASH FLOOD WATCH AS IS WITH CONTINUED CHANCES
FOR STRONG TO SEVERE THUNDERSTORMS NOW THROUGH SUNDAY...WITH
ADDITIONAL HEAVY RAINFALL POSSIBLE FOR THOSE LOCATIONS THAT HAVE
SEEN SIGNIFICANT RAINFALL AMOUNTS WEDNESDAY NIGHT AND THURSDAY
EVENING ACROSS SOUTH CENTRAL NORTH DAKOTA AND THE JAMES RIVER
VALLEY. SOILS HAVE LITTLE TO NO CAPACITY TO HOLD ADDITIONAL
WATER...ENHANCING RUNOFF AND THE POTENTIAL TO AGGRAVATE THE
ONGOING OVERLAND FLOODING ACROSS THE AREA. A COMPLEX OF
THUNDERSTORMS WITH HEAVY RAINFALL IS POSSIBLE AGAIN SATURDAY NIGHT
INTO SUNDAY. ADDITIONAL RAINFALL AMOUNTS OF 1 TO 3 INCHES ARE
POSSIBLE WITH LOCALLY HIGHER AMOUNTS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH SUNDAY EVENING FOR NDZ023-025-036-037-
046>048-050-051.
&&
$$
UPDATE...AYD
SHORT TERM...NH
LONG TERM...KS
AVIATION...TWH
HYDROLOGY...NH
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
933 PM CDT SUN JUN 23 2013
.UPDATE...
ISSUED AT 930 PM CDT SUN JUN 23 2013
LOW LEVEL JET STARTING TO HELP GENERATE SHOWERS AND THUNDERSTORMS
FROM SOUTHEAST NEBRASKA INTO SOUTHERN IOWA. THESE WILL LIKELY
CONTINUE TO DEVELOP NORTHWARD THROUGH THE EVENING. ALTHOUGH THE LOW
LEVEL JET ORIENTATION WOULD SUGGEST THAT THE BEST COVERAGE WILL
REMAIN SOUTHEAST OF OUR CWA. THIS IS SUPPORTED BY THE LATEST HRRR.
HOWEVER DID GO AHEAD AND ADD IN CHANCE POPS ACROSS OUR FAR SOUTH...AS
CANNOT COMPLETELY RULE OUT A STORM MAKING IT UP THERE AFTER ABOUT
08Z. ATTENTION THEN TURNS TO A WAVE COMING OUT OF THE ROCKIES.
CONVECTION ACROSS NORTHEAST COLORADO SHOULD MOVE EAST THROUGH
NEBRASKA OVERNIGHT. LIFT AND MOISTURE TRANSPORT AHEAD OF THIS WAVE
SHOULD ALLOW CONVECTION TO MAINTAIN ITSELF. PREFER THE FASTER TIMING
OF THE HRRR AS COMPARED TO THE NEW SLOWER 4KM NAM. THIS WOULD BRING
THE THREAT INTO OUR SOUTHWEST AROUND 12Z...PUSHING NORTHEAST THROUGH
THE MORNING HOURS. THIS FITS PRETTY WELL WITH THE GOING FORECAST...SO
DID NOT MAKE ANY CHANGES TO POPS TOMORROW. AS MENTIONED
BELOW...SEVERE THREAT SHOULD BE LOW WITH THIS MORNING
CONVECTION...ALTHOUGH MUCAPE APPROACHING 2000 J/KG MAY BE ENOUGH FOR
A FEW MARGINAL HAIL PRODUCING STORMS. TIMING OF THIS WAVE IS STILL
UNCERTAIN. IF IT ENDS UP SLOWER AND WE ARE ABLE TO GET MORE DAYTIME
HEATING AHEAD OF IT...THE SEVERE POTENTIAL WOULD PROBABLY INCREASE.
STILL TOUGH TO SAY WHAT HAPPENS TOMORROW NIGHT UNTIL WE SEE WHAT THE
FIRST WAVE DOES. SEEMS LIKELY STORMS FIRE IN THE WESTERN PLAINS
DURING THE AFTERNOON WITH A SECOND WAVE. WHETHER THESE SURVIVE INTO
OUR CWA IS STILL UP IN THE AIR...WITH MOST CONVECTION ALLOWING MODELS
SAYING NO...AND THE LOWER RESOLUTION NAM...GFS AND EC SUGGESTING YES.
PROBABLY DEPENDENT ON EXTENT OF DRYING...SUBSIDENCE AND CAPPING BEHIND
THE FIRST WAVE. WILL JUST HAVE TO CONTINUE TO MONITOR TRENDS.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 341 PM CDT SUN JUN 23 2013
A FRONTAL BOUNDARY CONTINUES TO PUSH THROUGH THE EASTERN PORTION OF
THE CWA THIS AFTERNOON AND IS EXPECTED TO EXIT THE AREA LATE THIS
AFTERNOON. CONVECTION WHICH WE EARLIER THOUGHT MIGHT DEVELOP IN OUR
SOUTHEAST LATE THIS AFTERNOON NOW LOOKS TO HOLD OFF UNTIL LATER IN
THE EVENING...WHEN THE BOUNDARY IS OUT OF OUR AREA...SO DO NOT
ANTICIPATE ANY DEVELOPMENT OVER OUR AREA. OTHERWISE...THE REMAINDER
OF THE NIGHT SHOULD BE QUIET AS WEAK HIGH PRESSURE BUILDS INTO THE
REGION. THIS WILL ALLOW FOR WINDS TO DIE OFF...AND CANNOT RULE OUT
SOME PATCHY FOG DEVELOPMENT WITH RECENT RAINS...THOUGH DID NOT
INCLUDE IN FORECAST AT THIS POINT WITH LOW CONFIDENCE. THE FORECAST
BECOMES MORE CHALLENGING LATER TONIGHT INTO MONDAY...WITH MODELS
DIFFERING ON THE TIMING AND STRENGTH OF ANOTHER SHORT WAVE LIFTING
UP OVER THE AREA DURING THE DAY ON MONDAY. MONDAYS SHORT WAVE IS
CURRENTLY VISIBLE ON THE WATER VAPOR IMAGERY NEAR LAS VEGAS NV. THE
GFS/GEM/4KM NAM AND SREF OFFER THE WETTER SOLUTIONS AS THEY ARE
STRONGER IN THE MID LEVELS...WHILE THE ECMWF AND NAM KEEP IT DRY
DURING THE DAYTIME HOURS...ALTHOUGH THE NAM DOES SHOW SOME WEAK PV
ON THE 1.5 SURFACE. ELECTED TO GO WITH THE WETTER SOLUTIONS WITH
850 MB THETA E ADVECTION INCREASING OVER THE AREA AS THE LOW
LEVEL JET CRANKS UP OUT OF EASTERN NEBRASKA. IN ADDITION THERE
WILL BE INSTABILITY AND SOME SHEAR...THOUGH IN THE ABSENCE OF
CAPPING WOULD EXPECT NO REAL UPDRAFT ENERGY TO BE STORED UP. SO
OTHER THAN SOME POSSIBLE SMALL HAIL WOULD NOT EXPECT SEVERE STORMS
DURING THE DAY. THIS OF COURSE WILL IMPACT HIGH TEMPERATURES...SO
WENT WITH COOLER GUIDANCES WITH HIGHS INTO THE LOWER 80S NORTHEAST
TO THE UPPER 80S ALONG THE MISSOURI RIVER CORRIDOR.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 341 PM CDT SUN JUN 23 2013
MONDAY NIGHT IS THE MOST ACTIVE PERIOD IN THE LONGER TERM. ANOTHER
STRONGER SHORT WAVE FOLLOWS MONDAY WAVE...WHICH WATER VAPOR SHOWS
CURRENTLY OFF OF THE CA COAST. INTERESTINGLY...THE HI RES MODELS
WHICH ARE SO ACTIVE ON MONDAY LEAVE MONDAY NIGHT DRY. HOWEVER THE
NAM AND ECMWF ARE WET...ESPECIALLY ALONG AND NORTH OF I 90. THE
ECMWF HAS BEEN VERY CONSISTENT WITH THIS FEATURE FOR 4 OR 5 DAYS
NOW. SO IT IS VERY HARD TO IGNORE. THE NAM IS STRONG WITH THE
PV 1.5...AND ABUNDANT INSTABILITY AND WIND SHEAR CONTINUES. MOST
OF THE RAINFALL WILL OCCUR IN THE EVENING HOURS...AGAIN WITH THE
HIGHEST CHANCES FOR HEAVIER RAINFALL ALONG AND NORTH OF I 90. NAM
PWATS IN THOSE AREAS AVERAGE 1.5 TO 2.0 INCHES AND SOME SEVERE
WEATHER IS POSSIBLE GIVEN THE INSTABILITY PARAMETERS. THE WAVE
QUICKLY EXITS AFTER MIDNIGHT...WHICH WILL LEAVE TUESDAY DRY AND
VERY WARM AND HUMID.
UPPER RIDGING THEN BUILDS AS ADVERTISED AND RETROGRADES WESTWARD
BY LATE WEEK AND NEXT WEEKEND. A SURFACE BOUNDARY MOVES THROUGH
OUR AREA LATE TUESDAY NIGHT SHIFTING OUR WINDS TO THE NORTHWEST
FOR WEDNESDAY. WITH BETTER MIXING...TEMPERATURES WILL STILL BE
QUITE WARM...WITH LESS HUMID CONDITIONS WEST OF I 29. AS THE UPPER
RIDGE RETROGRADES TO THE WEST CREATING A HIGHLY AMPLIFIED PATTERN...
IT STILL LOOKS AS THOUGH TEMPERATURES WILL START A COOLING TREND
ON THURSDAY...LASTING THROUGH THE WEEKEND.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 630 PM CDT SUN JUN 23 2013
CONVECTIVE CURIOSITIES AGAIN PART OF THE FORECAST PROCESS FOR 00Z
TAF COLLECTIVE. ONE WAVE WHICH RECENTLY PUSHED PAST THE FOUR
CORNERS WILL MOVE INTO THE AREA MONDAY MORNING. GIVEN THE LOW
LEVEL JET...AND APPARENT BOUNDARY ACROSS SOUTHEAST
NEBRASKA...EXPECT A FEW STORMS TO DEVELOP ALONG WARM ADVECTIVE
WING AND IMPACT KSUX AREA AFTER 09Z...AND THEN A BETTER COVERAGE
OF SHOWERS/STORMS BY MORNING HOURS FOR KFSD AND KSUX...BUT EXITING
NORTHEAST FAIRLY QUICKLY. UPSTREAM AND STRONGER WAVE UPSTREAM
AROUND RENO NV WILL FOLLOW...AND WILL LIKELY RESULT IN ADDITIONAL
CONVECTION ACROSS THE AREA...BUT FOR NOW HELD OFF MENTION UNTIL
AFTER 00Z. PROBABILITY OF MVFR FOG IS FAIRLY LOW...LIKELY HIGHEST
AROUND KSUX...BUT WILL ALSO HAVE INITIAL INCREASE IN CLOUDS FROM
CONVECTION TO SOUTH...AND WILL NOT MENTION ON THIS FORECAST SET.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
UPDATE...CHENARD
SHORT TERM...JM
LONG TERM...MJ
AVIATION...CHAPMAN
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
925 PM CDT SUN JUN 23 2013
.UPDATE...
WINDS HAVE GONE LIGHT LATE THIS EVENING UNDER CLEAR SKIES AND
SURFACE HIGH PRESSURE RIDGING. THE WINDS WILL TURN SOUTH BEHIND
THIS RETREATING HIGH PRESSURE AREA TONIGHT. ALREADY HAVE MID LEVEL
WAA CLOUDS/ACCAS AND COOLING TOPS IN WY/SE MT LATE THIS EVENING
MOVING QUICKLY EAST. THESE WILL CONTINUE TO MOVE EAST AND MAY
BECOME HIGH BASED SHOWERS/THUNDER AS THEY MOVE INTO WESTERN SD AND
INTO OUR WESTERN CWA LATER TONIGHT. THE LATEST HRRR MODEL SHOWS
SOME SPOTTY QPF LATER TONIGHT. ALREADY HAVE IN SLIGHT CHANCES WEST
IN THE CWA AFTER MIDNIGHT.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT
THE ACTIVE SUMMER PATTERN CONTINUES EARLY THIS WEEK AS RETURN
FLOW MOISTURE AND INSTABILITY MAKE A QUICK RETURN TO THE WESTERN
ZONES OVERNIGHT AND SPREADS EAST MONDAY AND MONDAY EVENING.
MODELS ARE AGAIN OFFERING A CHALLENGING FORECAST WITH TIMING AND
STRENGTH OF SHORTWAVES AND CONVECTION...BUT THUNDERSTORMS LOOK
LIKE A GOOD BET MONDAY NIGHT MOST LOCATIONS AND AGAIN TUESDAY
NIGHT IN THE EAST. SPC HAS AREA IN SLIGHT RISK FOR MONDAY NIGHT
AND THE EASTERN PORTION FOR TUESDAY.
DESPITE RISING HEIGHTS...DEEP SOUTHWEST FLOW ALOFT WILL CONTINUE
TO EJECT SHORTWAVES INTO THE UPPER PLAINS. WITH INSTABILITY
RETURN IN THE WEST LATE TONIGHT HAVE ADDED SMALL POPS TO THE
FORECAST FOR AREAS ALONG AND WEST OF THE MISSOURI RIVER.
HEAT...MOISTURE AND INSTABILITY WILL INCREASE THE NEXT FEW DAYS
WITH TEMPS CLIMBING INTO THE UPPER 80S AND MID 90S BY TUESDAY.
THE HEAT INDEX WILL CLIMB INTO THE MID TO UPPER 90S ON TUESDAY.
AS MENTIONED ABOVE...MODELS IN ARE NOT IN VERY GOOD AGREEMENT
WITH TIMING OF CONVECTION...BUT OVERALL FEEL CONFIDENT FOR
THUNDERSTORMS FOR BOTH MONDAY AND TUESDAY EVENINGS...POSSIBLY
SEVERE AS INSTABILITY INCREASES.
.LONG TERM...WEDNESDAY THROUGH SUNDAY
IT APPEARS THE THEMES RUNNING THROUGHOUT THE EXTENDED ARE WARM AND
MOSTLY DRY. AT THIS POINT...POPS/WX MENTION DO NOT SHOW UP IN THE
OUT PERIODS BASICALLY UNTIL SATURDAY LATE AFTERNOON/EARLY EVENING.
UNTIL THEN...REBOUNDING MID/UPPER LEVEL HEIGHTS ARE FORECAST TO
DEVELOP ACROSS THE WESTERN TWO-THIRDS OF THE CONUS STARTING
WEDNESDAY AND PERSIST THROUGH THE END OF THE PERIOD. A LOW
PRESSURE SYSTEM IS PROGGED TO TRY WORKING THROUGH THE TOP OF THE
RIDGE...IN EFFECT...FLATTENING IT SOMEWHAT OVER THE WEEKEND AND
BRINGING A SMALL CHANCE AT CONVECTION ACROSS THE CWA BY SATURDAY
EVENING. AT THIS TIME...700HPA THERMAL PROGS ARE AT OR ABOVE +14C
ON SATURDAY...SO IT WILL TAKE QUITE A BIT OF MOISTURE/INSTABILITY
AND STRONG FORCING AROUND TO GET STORMS TO DEVELOP IN THAT WARM OF
A MID-LEVEL ENVIRONMENT. SPEAKING OF WARM...WITH HEIGHTS RISING IN
THE ATMOSPHERE...A GOOD CHUNK OF THE EXTENDED SHOULD BE LOOKING AT
NEAR TO ABOVE NORMAL HIGH TEMPERATURES IN THE 80S AND 90S DURING
THE MID TO LATE PORTIONS OF THE WEEK.
&&
.AVIATION...
00Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
VFR CONDITIONS ARE EXPECTED AT ALL TERMINALS THROUGH TONIGHT AND
MONDAY. AN UPPER LEVEL LOW PRESSURE TROUGH ALONG WITH RETURNING
WAA WILL SPREAD MID LEVEL CLOUDS ACROSS THE REGION THROUGH MONDAY.
WITH INSTABILITY ALSO RETURNING/INCREASING...SOME
SHOWERS/THUNDERSTORMS SHOULD ALSO DEVELOP MAINLY LATE TONIGHT AND
MONDAY. LEFT ANY MENTION OUT OF THE TERMINALS AT THIS TIME WITH
THE UNCERTAINTY OF LOCATION AND TIMING INVOLVED.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...MOHR
SHORT TERM...SCARLETT
LONG TERM...DORN
AVIATION...MOHR
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
952 PM CDT SUN JUN 23 2013
.UPDATE...
SHORTWAVE OVER SOUTHEASTERN AND EASTERN NEW MEXICO IN THE
SOUTHWESTERLY UPPER FLOW ACROSS THE PANHANDLES ALLOWING FOR
ADDITIONAL CONVECTION TO DEVELOP IN THE FAR EASTERN PLAINS OF NEW
MEXICO MOVING NORTHEAST INTO THE SOUTHWESTERN TEXAS PANHANDLE.
EXPANDED THE POPS THROUGH 06Z MONDAY A LITTLE FURTHER WESTWARD TO
ACCOUNT FOR THIS ROUND OF CONVECTION. SHORT RANGE MODELS IN GOOD
AGREEMENT SHOWING CONVECTION DEVELOPING ACROSS THE NORTHEAST TEXAS
AND EASTERN OKLAHOMA PANHANDLES TOWARD 09Z MONDAY. INTRODUCED THE 10
POP RULE OVER THE EASTERN SECTIONS OF THE PANHANDLES TO ACCOUNT FOR
THIS POSSIBILITY. DID NOTICE A LONE THUNDERSTORM ACROSS THE
SOUTHEASTERN TEXAS PANHANDLE LAST NIGHT AROUND 09Z SUNDAY OR SO...AND
CANNOT RULE OUT A SIMILAR SCENARIO ACROSS THE NORTHEASTERN OR EASTERN
SECTIONS OF THE FORECAST AREA LATER TONIGHT. LOW LEVEL JET ACROSS THE
EASTERN PANHANDLES LATE TONIGHT MAY ALSO HELP ADDITIONAL CONVECTION
TO DEVELOP LATE TONIGHT. ADJUSTED WIND AND SKY GRIDS TONIGHT...AND
ALSO POPULATED THE SMOKE MANAGEMENT GRIDS WITH THE LATEST NAM DATA
AND UPDATED THE LAL AND 20 FOOT WIND GRIDS. OTHERWISE...NO OTHER
CHANGES MADE TO PREVIOUS FORECAST AND GRIDS.
ALL PUBLIC AND FIRE WEATHER PRODUCTS HAVE BEEN UPDATED AND SENT.
SCHNEIDER
&&
.PREV DISCUSSION... /ISSUED 636 PM CDT SUN JUN 23 2013/
AVIATION...
00Z TAF CYCLE
A SOUTHWESTERLY UPPER FLOW ALONG WITH AN UPPER TROUGH OVER THE PANHANDLES
THIS EVENING AND A DRYLINE LOCATED ACROSS THE WESTERN PANHANDLES WILL
ALLOW FOR ISOLATED CONVECTION ACROSS THE OKLAHOMA PANHANDLE AND THE
SOUTH CENTRAL AND SOUTHEASTERN TEXAS PANHANDLE THROUGH 05Z MONDAY.
CONFIDENCE IN THE CONVECTION MOVING OVER EITHER THE GUYMON OR
AMARILLO TAF SITES IS LOW...HOWEVER WILL INCLUDE VCTS REMARK IN
PREVAILING GROUP AT BOTH TAF SITES THIS EVENING AND WILL CONTINUE TO
MONITOR. OTHERWISE...VFR CONDITIONS WITH MAINLY SCATTERED TO BROKEN
HIGH LEVEL CLOUDS AND SOME SCATTERED HIGH BASED LOW CLOUDS DURING THE
AFTERNOON HOURS UNTIL AROUND SUNSET OR AROUND 02Z TO 04Z MONDAY WILL
PREVAIL. SOUTHEASTERLY TO SOUTHERLY WINDS OF AROUND 10 TO 15 KNOTS OR
LESS AT THE DALHART AND GUYMON TAF SITES UNTIL AROUND 04Z TO 06Z
MONDAY...THEN INCREASING TO AROUND 15 TO 25 KNOTS WITH HIGHER GUSTS
AFTER 04Z TO 06Z MONDAY. SOUTHEASTERLY TO SOUTHERLY WINDS OF 15 TO 25
KNOTS WITH HIGHER GUSTS WILL PREVAIL AT THE AMARILLO TAF SITE THROUGH
THE TAF FORECAST PERIOD.
NOTE TO USERS OF SURFACE OBSERVATION FROM RICK HUSBAND INTERNATIONAL
AIRPORT KAMA...COMMUNICATIONS PROBLEM WITH DATA LINE HAS PREVENTED
LONG-LINE DISSEMINATION OF SURFACE OBS. DATA COLLECTION PLATFORM AT
KAMA ASOS IS FUNCTIONING PROPERLY WITH CONTINUOUS MONITORING OF ALL
ELEMENTS BY AMARILLO NATIONAL WEATHER SERVICE FORECAST STAFF.
SCHNEIDER
PREV DISCUSSION... /ISSUED 319 PM CDT SUN JUN 23 2013/
DISCUSSION...
JUST ONE MORE DAY OF THIS ACTIVE WEATHER PATTERN THAT THE REGION HAS
BEEN UNDER FOR OVER A WEEK NOW.
TONIGHT INTO TOMORROW...PRECIP CHANCES...THOUGH
MENTIONABLE...CONTINUE TO DECLINE AS DRY AIR ADVECTION CONTINUES.
PRECIPITABLE WATER VALUES ON THIS MORNINGS SOUNDING SHOW 0.79
INCHES...WHICH IS 92 PERCENT OF NORMAL...BUT A FAR CRY FROM THE 1
PLUS INCH VALUES WE/VE SEEN LATELY. IN ADDITION...IN THE WAKE OF THE
UPPER LEVEL TROUGH THAT MOVE THROUGH EARLY THIS MORNING...THERE IS
SOME UPPER LEVEL SHORT WAVE RIDGING OVER THE REGION. THIS SHOULD KEEP
COVERAGE OF STORMS VERY LIMITED. HOWEVER...IT IS INTERESTING TO NOTE
THAT THE RAP HIGH RESOLUTION MODEL SHOWS MORE COVERAGE THAN
YESTERDAY. IF ANY STORMS DEVELOP EITHER THIS AFTERNOON OR
TOMORROW...THE POTENTIAL REMAINS FOR MARGINALLY SEVERE HAIL AND DRY
AND HYBRID DOWNBURSTS LEADING TO STRONG WINDS.
TUESDAY THROUGH THURSDAY...INCREASING CONFIDENCE WITH VERY GOOD MODEL
AGREEMENT AND CONSISTENCY THAT THE RIDGE WILL BUILD OVER THE
SOUTHWEST THROUGH THIS PERIOD BRINGING A DRY AND HOT WEATHER PATTERN
THROUGH THE WEEK. STAYED CLOSE TO THE PREVIOUS FORECAST STILL
FAVORING HIGHER MAX TEMPS IN THE NORTHWESTERN PANHANDLES...WHICH
HAVE SEEN VERY LITTLE RAIN...WHILE KEEPING THE SOUTHEASTERN TX
PANHANDLE A FEW DEGREES LOWER DUE TO THE WET SOIL CONDITIONS.
HOWEVER...BY THE END OF THE WEEK...THESE DIFFERENCES MAY BE
NEGLIGIBLE AS THE SOILS DRY.
FRIDAY THROUGH SUNDAY...MODELS CONTINUED THE TREND OF SHOWING A
PERSISTENT RIDGE CONTINUING THROUGH THIS PERIOD. THE COLD FRONT WHICH
WAS SHOWN IN THE GFS TO ARRIVE ON FRIDAY...HAS ALL BUT DISAPPEARED IN
THE 12Z RUN. THUS...STAYED CLOSE TO THE PREVIOUS FORECAST WITH HOT
AND DRY WEATHER CONTINUING THROUGH THE WEEK.
JOHNSON
AVIATION...
FOR THE 18Z TAFS...ANY ISOLATED LATE AFTERNOON AND EARLY EVENING
THUNDERSTORMS ARE EXPECTED TO REMAIN EAST OF TERMINALS. SCATTERED
HIGH-BASED CUMULUS OR ALTOCUMULUS WILL BE THE ONLY CLOUDS OTHER THAN
CIRRUS FOR THIS FORECAST. WIND SHIFT LINE WHICH IS MOVING ACROSS
NORTHWESTERN PART OF FORECAST AREA WILL CAUSE VARIABILITY IN SURFACE
WIND DIRECTION AT NORTHERN TERMINALS UNTIL AROUND 22 OR 23Z
TODAY...WHEN SOUTHERLY SURFACE WINDS RESUME AND COMMENCE GUSTING TO
AROUND 25 KT. FOR KAMA...SOUTHERLY SURFACE WINDS EXPECTED TO
PREVAIL...WITH GUSTS ABOVE 25 KT OCCURRING BETWEEN 21Z TODAY AND 06Z
MONDAY. VFR FORECAST CONTINUES NEXT 24 HOURS.
NOTE TO USERS OF SURFACE OBSERVATION FROM RICK HUSBAND INTERNATIONAL
AIRPORT KAMA...COMMUNICATIONS PROBLEM WITH DATA LINE HAS PREVENTED
LONG-LINE DISSEMINATION OF SURFACE OBS. DATA COLLECTION PLATFORM AT
KAMA ASOS IS FUNCTIONING PROPERLY WITH CONTINUOUS MONITORING OF ALL
ELEMENTS BY AMARILLO NATIONAL WEATHER SERVICE FORECAST STAFF.
COCKRELL
FIRE WEATHER...
ELEVATED TO NEAR CRITICAL FIRE WEATHER CONDITIONS MAY OCCUR TOMORROW
IN THE WESTERN OKLAHOMA AND FAR NORTHWESTERN TEXAS
PANHANDLES...THOUGH UNCERTAINTY REMAINS. MINIMUM RELATIVE HUMIDITY
VALUES SHOULD BE BELOW 15 PERCENT. HOWEVER...THOUGH WINDS ARE
EXPECTED TO BE NEAR 20 MPH...IT IS UNCERTAIN IF THE SURFACE TROUGH
WHICH RESULTED IN LIGHTER WINDS TODAY WILL BE A FACTOR TOMORROW AS
WELL. THOUGH MINIMUM RELATIVE HUMIDITY VALUES WILL DROP BELOW 20
THROUGH THE REMAINDER OF THE WEEK...AS WE SEE A DRIER PATTERN...NO
ADDITIONAL ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED
AT THIS TIME AS WINDS SHOULD BE LIGHT.
JOHNSON
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
08/11
AREA FORECAST DISCUSSION
NWS AMARILLO TX
636 PM CDT SUN JUN 23 2013
.AVIATION...
00Z TAF CYCLE
A SOUTHWESTERLY UPPER FLOW ALONG WITH AN UPPER TROUGH OVER THE PANHANDLES
THIS EVENING AND A DRYLINE LOCATED ACROSS THE WESTERN PANHANDLES WILL
ALLOW FOR ISOLATED CONVECTION ACROSS THE OKLAHOMA PANHANDLE AND THE
SOUTH CENTRAL AND SOUTHEASTERN TEXAS PANHANDLE THROUGH 05Z MONDAY.
CONFIDENCE IN THE CONVECTION MOVING OVER EITHER THE GUYMON OR
AMARILLO TAF SITES IS LOW...HOWEVER WILL INCLUDE VCTS REMARK IN
PREVAILING GROUP AT BOTH TAF SITES THIS EVENING AND WILL CONTINUE TO
MONITOR. OTHERWISE...VFR CONDITIONS WITH MAINLY SCATTERED TO BROKEN
HIGH LEVEL CLOUDS AND SOME SCATTERED HIGH BASED LOW CLOUDS DURING THE
AFTERNOON HOURS UNTIL AROUND SUNSET OR AROUND 02Z TO 04Z MONDAY WILL
PREVAIL. SOUTHEASTERLY TO SOUTHERLY WINDS OF AROUND 10 TO 15 KNOTS OR
LESS AT THE DALHART AND GUYMON TAF SITES UNTIL AROUND 04Z TO 06Z
MONDAY...THEN INCREASING TO AROUND 15 TO 25 KNOTS WITH HIGHER GUSTS
AFTER 04Z TO 06Z MONDAY. SOUTHEASTERLY TO SOUTHERLY WINDS OF 15 TO 25
KNOTS WITH HIGHER GUSTS WILL PREVAIL AT THE AMARILLO TAF SITE THROUGH
THE TAF FORECAST PERIOD.
NOTE TO USERS OF SURFACE OBSERVATION FROM RICK HUSBAND INTERNATIONAL
AIRPORT KAMA...COMMUNICATIONS PROBLEM WITH DATA LINE HAS PREVENTED
LONG-LINE DISSEMINATION OF SURFACE OBS. DATA COLLECTION PLATFORM AT
KAMA ASOS IS FUNCTIONING PROPERLY WITH CONTINUOUS MONITORING OF ALL
ELEMENTS BY AMARILLO NATIONAL WEATHER SERVICE FORECAST STAFF.
SCHNEIDER
&&
.PREV DISCUSSION... /ISSUED 319 PM CDT SUN JUN 23 2013/
DISCUSSION...
JUST ONE MORE DAY OF THIS ACTIVE WEATHER PATTERN THAT THE REGION HAS
BEEN UNDER FOR OVER A WEEK NOW.
TONIGHT INTO TOMORROW...PRECIP CHANCES...THOUGH
MENTIONABLE...CONTINUE TO DECLINE AS DRY AIR ADVECTION CONTINUES.
PRECIPITABLE WATER VALUES ON THIS MORNINGS SOUNDING SHOW 0.79
INCHES...WHICH IS 92 PERCENT OF NORMAL...BUT A FAR CRY FROM THE 1
PLUS INCH VALUES WE/VE SEEN LATELY. IN ADDITION...IN THE WAKE OF THE
UPPER LEVEL TROUGH THAT MOVE THROUGH EARLY THIS MORNING...THERE IS
SOME UPPER LEVEL SHORT WAVE RIDGING OVER THE REGION. THIS SHOULD KEEP
COVERAGE OF STORMS VERY LIMITED. HOWEVER...IT IS INTERESTING TO NOTE
THAT THE RAP HIGH RESOLUTION MODEL SHOWS MORE COVERAGE THAN
YESTERDAY. IF ANY STORMS DEVELOP EITHER THIS AFTERNOON OR
TOMORROW...THE POTENTIAL REMAINS FOR MARGINALLY SEVERE HAIL AND DRY
AND HYBRID DOWNBURSTS LEADING TO STRONG WINDS.
TUESDAY THROUGH THURSDAY...INCREASING CONFIDENCE WITH VERY GOOD MODEL
AGREEMENT AND CONSISTENCY THAT THE RIDGE WILL BUILD OVER THE
SOUTHWEST THROUGH THIS PERIOD BRINGING A DRY AND HOT WEATHER PATTERN
THROUGH THE WEEK. STAYED CLOSE TO THE PREVIOUS FORECAST STILL
FAVORING HIGHER MAX TEMPS IN THE NORTHWESTERN PANHANDLES...WHICH
HAVE SEEN VERY LITTLE RAIN...WHILE KEEPING THE SOUTHEASTERN TX
PANHANDLE A FEW DEGREES LOWER DUE TO THE WET SOIL CONDITIONS.
HOWEVER...BY THE END OF THE WEEK...THESE DIFFERENCES MAY BE
NEGLIGIBLE AS THE SOILS DRY.
FRIDAY THROUGH SUNDAY...MODELS CONTINUED THE TREND OF SHOWING A
PERSISTENT RIDGE CONTINUING THROUGH THIS PERIOD. THE COLD FRONT WHICH
WAS SHOWN IN THE GFS TO ARRIVE ON FRIDAY...HAS ALL BUT DISAPPEARED IN
THE 12Z RUN. THUS...STAYED CLOSE TO THE PREVIOUS FORECAST WITH HOT
AND DRY WEATHER CONTINUING THROUGH THE WEEK.
JOHNSON
AVIATION...
FOR THE 18Z TAFS...ANY ISOLATED LATE AFTERNOON AND EARLY EVENING
THUNDERSTORMS ARE EXPECTED TO REMAIN EAST OF TERMINALS. SCATTERED
HIGH-BASED CUMULUS OR ALTOCUMULUS WILL BE THE ONLY CLOUDS OTHER THAN
CIRRUS FOR THIS FORECAST. WIND SHIFT LINE WHICH IS MOVING ACROSS
NORTHWESTERN PART OF FORECAST AREA WILL CAUSE VARIABILITY IN SURFACE
WIND DIRECTION AT NORTHERN TERMINALS UNTIL AROUND 22 OR 23Z
TODAY...WHEN SOUTHERLY SURFACE WINDS RESUME AND COMMENCE GUSTING TO
AROUND 25 KT. FOR KAMA...SOUTHERLY SURFACE WINDS EXPECTED TO
PREVAIL...WITH GUSTS ABOVE 25 KT OCCURRING BETWEEN 21Z TODAY AND 06Z
MONDAY. VFR FORECAST CONTINUES NEXT 24 HOURS.
NOTE TO USERS OF SURFACE OBSERVATION FROM RICK HUSBAND INTERNATIONAL
AIRPORT KAMA...COMMUNICATIONS PROBLEM WITH DATA LINE HAS PREVENTED
LONG-LINE DISSEMINATION OF SURFACE OBS. DATA COLLECTION PLATFORM AT
KAMA ASOS IS FUNCTIONING PROPERLY WITH CONTINUOUS MONITORING OF ALL
ELEMENTS BY AMARILLO NATIONAL WEATHER SERVICE FORECAST STAFF.
COCKRELL
FIRE WEATHER...
ELEVATED TO NEAR CRITICAL FIRE WEATHER CONDITIONS MAY OCCUR TOMORROW
IN THE WESTERN OKLAHOMA AND FAR NORTHWESTERN TEXAS
PANHANDLES...THOUGH UNCERTAINTY REMAINS. MINIMUM RELATIVE HUMIDITY
VALUES SHOULD BE BELOW 15 PERCENT. HOWEVER...THOUGH WINDS ARE
EXPECTED TO BE NEAR 20 MPH...IT IS UNCERTAIN IF THE SURFACE TROUGH
WHICH RESULTED IN LIGHTER WINDS TODAY WILL BE A FACTOR TOMORROW AS
WELL. THOUGH MINIMUM RELATIVE HUMIDITY VALUES WILL DROP BELOW 20
THROUGH THE REMAINDER OF THE WEEK...AS WE SEE A DRIER PATTERN...NO
ADDITIONAL ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED
AT THIS TIME AS WINDS SHOULD BE LIGHT.
JOHNSON
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
08/11
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
1143 PM CDT FRI JUN 21 2013
.UPDATE...
CONVECTION WAS WINDING DOWN AT THIS HOUR. LIGHT SHOWERS AND A FEW
ISOLATED THUNDERSTORMS WERE THE ONLY ACTIVITY THAT REMAINED.
THEREFORE THE SEVERE THUNDERSTORM WATCH WAS CANCELLED.
&&
.AVIATION...
A FEW LIGHT SHOWERS REMAINED THIS EVENING BUT ARE NOT EXPECTED TO
AFFECT EITHER TAF SITE. A WEAK OUTFLOW BOUNDARY MAY BRIEFLY SHIFT
WINDS TO THE NORTH AT KLBB WITHIN THE NEXT ONE TO TWO HOURS BUT
WIND SPEEDS ARE ANTICIPATED TO BE LIGHT. SOUTHERLY WINDS WILL
INCREASE AGAIN ON SATURDAY AFTERNOON AND MAY LEAD TO LIGHT
VISIBILITY RESTRICTIONS DUE TO BLOWING DUST. ANOTHER CHANCE OF
THUNDERSTORMS WILL ALSO EXIST SATURDAY EVENING BUT CONFIDENCE IS
NOT HIGH ENOUGH TO PLACE IN THE TAF AT THE MOMENT.
&&
.PREV DISCUSSION... /ISSUED 652 PM CDT FRI JUN 21 2013/
UPDATE...
DISTURBANCE EDGING INTO WESTERN NEW MEXICO EXPECTED TO LEAD TO
INCREASING THUNDERSTORMS THROUGH THE EVENING...SHOULD PERSIST
LATER THAN LAST NIGHT. INITIAL ACTIVITY NEAR THE NEW MEXICO BORDER
FAIRLY ISOLATED AND STILL UNCERTAIN HOW MUCH ADDITIONAL DEVELOPMENT
WILL OCCUR...MIXED SIGNALS FROM SHORT-TERM SOLUTIONS. HAIL AND
HIGH WIND THREAT SHOULD TRANSITION TO OUTFLOW DRIVEN STORMS WITH
WIND AND DUST AS PROBABLE ISSUES. SEVERE THUNDERSTORM WATCH VALID
UNTIL 2 AM CDT TONIGHT. RMCQUEEN
AVIATION...
A FEW ISOLATED THUNDERSTORMS HAVE DEVELOPED NEAR THE TEXAS/NEW
MEXICO STATE LINE AND WILL CONTINUE TO MOVE EAST THIS EVENING.
HOWEVER...CONFIDENCE IS LOW ON WHETHER ANY STORMS WILL AFFECT EITHER
TAF SITE. WINDS WILL PICK UP TOMORROW AFTERNOON AGAIN AND LEAD TO
LIGHT VISIBILITY RESTRICTIONS DUE TO BLOWING DUST.
PREV DISCUSSION... /ISSUED 316 PM CDT FRI JUN 21 2013/
SHORT TERM...
FORECAST REVOLVES AROUND THUNDER CHANCES LATE THIS AFTERNOON INTO
TONIGHT. THE REGION REMAINS UNDER SOUTHWEST FLOW ALOFT...WITH ONE
NOTABLE SHORTWAVE TROUGH ACROSS THE PANHANDLES EXITING TO THE
NORTHEAST AND ANOTHER AREA OF LIFT SEEN ON WATER VAPOR IMAGERY
APPROACHING THROUGH AZ. WAS CONCERNED THE FIRST WAVE COULD SPARK A
FEW STORMS ACROSS THE EASTERN ZONES THIS AFTERNOON...AS EARLIER RAP
AND HRRR SOLUTIONS SUGGESTED...BUT THEY HAVE NOW BACKED OFF ON THIS
AND WITH WAVE EXITING PROSPECTS FOR THIS ARE LOW. ALTHOUGH WE WILL
BE POSITIONED BETWEEN THE TWO SYNOPTIC AREAS OF FORCING FOR ASCENT
THIS EVENING...STRONG HEATING AND GOOD MOISTURE LEVELS WERE
RESULTING IN STRONG INSTABILITY AND MINIMAL INHIBITION OVER MUCH OF
THE REGION...WITH 19Z MLCAPE VALUES ANALYZED AOA 2500 J/KG FOR MOST
OF THE FA. IN ADDITION...AN AREA OF LOW-LEVEL MOISTURE CONVERGENCE
WAS NOTED FROM THE CENTRAL TEXAS PANHANDLE SOUTHWESTWARD INTO THE
LEE TROUGH ACROSS SOUTHEASTERN NEW MEXICO. UP TO THIS POINT...STORMS
HAVE BEEN CONFINED TO LOCATIONS IMMEDIATELY ALONG AND EAST OF THE
SACRAMENTO MOUNTAINS...BUT EXPECT ADDITIONAL DEVELOPMENT
NORTHEASTWARD FROM THERE UP INTO THE WESTERN/CENTRAL PANHANDLE
THROUGH LATE THIS AFTERNOON. THE ACTIVITY MAY TRY AND CONGEAL
SOMEWHAT AS IT MOVES EASTWARD ACROSS THE CAPROCK THIS
EVENING...PERHAPS MAKING IT INTO THE ROLLING PLAINS LATER
TONIGHT...THOUGH IT SHOULD BE WANING IN INTENSITY BY LATE EVENING.
EARLY ON...STRONG INSTABILITY AND WEAK TO MODEST WIND SHEAR WILL
SUPPORT A SEVERE THREAT WITH LARGE HAIL...DAMAGING WINDS...LOCALLY
HEAVY RAIN AND THE PROSPECTS FOR BLOWING DUST. HAVE EXPANDED CHANCE
POPS TO ENCOMPASS NEARLY THE ENTIRE SOUTHERN PANHANDLE AND SOUTH
PLAINS THROUGH 06Z BEFORE DROPPING POPS BELOW 15 PERCENT AFTER 06Z.
TEMPERATURES TONIGHT WILL BE MILD AS MOIST SOUTHERLY LOW-LEVEL FLOW
CONTINUES AND HAVE GONE WITH TEMPERATURES SIMILAR TO WHAT WE SAW
THIS MORNING.
TOMORROW WILL BRING ANOTHER HOT DAY WITH LITTLE CHANGE IN THE
OVERALL PATTERN. STRONG DAYTIME HEATING...WITH HIGHS IN THE MIDDLE
90S AND SUFFICIENT MOISTURE...COMBINED WITH CONVERGENCE ALONG A SFC
TROUGH/DRYLINE WILL BRING ANOTHER THREAT OF STRONG/SEVERE
STORMS...FAVORING THE WESTERN ZONES INITIALLY IN THE LATE AFTERNOON
HOURS...THEN EXPANDING EAST.
LONG TERM...
MAIN ISSUE TODAY IS TIMING TRANSITION FROM AFTN THUNDERSTORM
REGIME ACROSS THE WRN ZONES TO HOT AND DRY AREAWIDE. 12Z MODEL
RUNS NOW A BIT SLOWER IN REPLACING THE WRN CONUS UPPER TROUGH WITH
AN AMPLIFYING RIDGE. IT NOW LOOKS LIKE THE LEE SFC TROUGH COULD
REMAIN ACTIVE INTO MONDAY WITH SWLY FLOW ALOFT BEFORE THAT RIDGE
AMPLIFICATION BEGINS OVER THE SRN ROCKIES. THAT SHOULD FINALLY
SHUT PRECIPITATION DOWN OVER THE AREA. AS A RESULT HAVE EXTENDED
SLIGHT CHANCE MENTION INTO MONDAY AFTN AND EVENING. TEMPS WILL
THEN WARM AS THE RIDGE BUILDS OVER THE ROCKIES AND LOW LEVELS DRY
OUT A BIT...WITH HIGH TEMPS LIKELY APPROACHING 10F WARMER THAN
NORMAL BY WEDNESDAY AND THURSDAY. WILL END WITH MENTION OF AN
OUTSIDE SHOT OF PRECIP REENTERING THE PICTURE TOWARD FRIDAY AS
NORTHERLY MID TO UPPER FLOW OVER THE PLAINS COULD SEND A COLD
FRONT AND/OR UPPER DISTURBANCE TOWARD THE FCST AREA. FOR NOW THAT
POSSIBILITY TOO REMOTE TO ADD TO FCST.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 64 93 63 94 63 / 30 20 20 20 20
TULIA 66 94 66 96 67 / 30 20 20 20 20
PLAINVIEW 68 93 68 95 68 / 30 20 20 20 20
LEVELLAND 69 93 68 93 69 / 30 20 20 20 20
LUBBOCK 73 93 70 96 69 / 30 10 20 20 20
DENVER CITY 67 95 68 96 69 / 30 20 20 20 20
BROWNFIELD 70 94 68 95 70 / 30 20 20 20 20
CHILDRESS 72 97 70 97 70 / 20 10 10 10 10
SPUR 72 95 71 95 70 / 20 10 10 10 10
ASPERMONT 73 97 72 97 71 / 20 10 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
01
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
829 PM EDT SUN JUN 23 2013
.SYNOPSIS...
A TYPICAL SUMMER PATTERN CONTINUES WITH HIGH PRESSURE SITUATED
ACROSS THE SOUTHEAST AND SOUTHWEST FLOW KEEPING US WARM AND HUMID
WITH A DAILY THREAT OF SHOWERS AND STORMS THROUGH AT LEAST
MIDWEEK. A COLD FRONT WILL APPROACH THE REGION FROM THE NORTHWEST
LATE IN THE WEEK WITH MORE WIDESPREAD SHOWERS AND THUNDERSTORMS
LIKELY.
&&
.NEAR TERM /THROUGH MONDAY/...
AS OF 310 PM EDT SUNDAY...
THE OVERALL WEATHER PATTERN HAS AN UPPER LEVEL TROUGH TRACKING
NORTHEAST FROM THE SOUTHERN OHIO VALLEY THIS AFTERNOON TO THE
NORTHERN MID ATLANTIC TOMORROW. WHILE THIS TROUGH IS MOVING
NORTHEAST...AN UPPER LEVEL RIDGE WILL TRACK SOUTHWEST FROM BERMUDA
TOWARDS FLORIDA. EVENTUALLY THIS RIDGE WILL RESIDE OVER THE GULF
STATES BY THE MIDDLE OF THE WEEK.
FOR THE IMMEDIATE AREA...THERE WILL BE VERY LITTLE CHANGE IN THE
WEATHER PATTERN OVER THE NEXT 24 HOURS. CONVECTION THIS AFTERNOON
HAS BEEN SLOW TO DEVELOP BY SOME MID LEVEL DRY AIR. THERE ARE A FEW
CELLS LIVING OFF OF MOISTURE AND MODEST INSTABILITIES THAT COULD
GENERATE MORE ACTIVITY FROM GUST FRONTS AS THEY COLLAPSE. CONFIDENCE
IS LOW ON AREAL COVERAGE...THEREFORE HAVE PLACED 20-30 POP ACROSS
MOST OF THE AREA. THE BETTER COVERAGE OF STORMS ARE SOUTH OF THE
AREA AND WILL MAKE A RUN AT RNK SOUTHERN TIER COUNTIES LATER THIS
AFTERNOON INTO THIS EVENING. THIS AFTERNOON AND EVENING
THUNDERSTORMS WILL FADE WITH THE SETTING OF THE SUN.
OVERNIGHT...MUGGY CONDITIONS WITH PATCHY VALLEY FOG DEVELOPING
DURING THE EARLY MORNING HOURS. ON MONDAY...CONTINUED HUMID
CONDITIONS WITH HIT AND MISS DIURNAL CONVECTION.
IF SHOWERS AND THUNDERSTORMS ARE HELD DOWN TOMORROW...THE
AREA WILL SEE SLIGHTLY WARMER TEMPERATURES THAN TODAY.
TEMPERATURES TOMORROW WILL RANGE FROM THE UPPER 70S TO MID 80S
ACROSS THE MOUNTAINS TO THE UPPER 80S IN THE EAST.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
AS OF 215 PM EDT SUNDAY...
HEIGHTS SHOULD CONTINUE TO SLOWLY BUILD INTO MID WEEK AS
SURFACE RIDGING REMAINS OFFSHORE WITH A DEEP WEST TO SW FLOW IN
PLACE. THIS WILL RESULT IN A PERSISTENT PATTERN OF DIURNAL
CONVECTION DURING HEATING...AND MAINLY CLEAR/PC AT NIGHT
ONCE ANY EVENING SHRA/TSRA FADE. HOWEVER APPEARS BEST COVERAGE
OF SHOWERS/STORMS MAY COME ON TUESDAY AS A WEAK MID LEVEL WAVE
RIDES THROUGH THE ZONAL FLOW AROUND THE RIDGE AND PERHAPS
COINCIDES WITH MAX HEATING. THIS SUPPORTED BY THE LASTEST SREF AND
FORECAST LOBE OF HIGHER 85H THETA-E THAT LOOKS TO ROTATE IN FROM
THE WEST TUESDAY AFTERNOON. LACK OF BACKING LOW LEVEL FLOW COULD
INHIBIT COVERAGE A BIT SO STAYING WITH OVERALL CHANCE POPS TUESDAY
INTO TUESDAY EVENING. PASSAGE OR SPLIT OF THIS FEATURE SHOULD ACT
TO ENHANCE THE WESTERLY FLOW ON WEDNESDAY AS THE CWA SLIDES IN
BETWEEN THE TUESDAY FEATURE AND THE NEXT STRONGER UPSTREAM VORT.
THIS MAY ALLOW FOR A BIT MORE CONVERGENCE WESTERN SLOPES WHILE
LIMITING COVERAGE EAST OF THE MOUNTAINS DESPITE DECENT CAPES.
THEREFORE TRIMMED BACK POPS IN ALL EXCEPT THE WESTERN AREAS WHERE
WILL RUN WITH HIGHER CHANCES...RANGING TO ONLY OVERALL SLIGHT
POPS OUT EAST.
INCREASED RIDGING ALOFT ALONG WITH WARMING 85H TEMPS TO
AROUND +20C AND WEST WINDS WILL PUSH HIGHS ABOVE 90 IN THE
PIEDMONT/FOOTHILLS WITH 80S ELSW BOTH TUE/WED. LOWS SHOULD BE
QUITE MUGGY AND MOSTLY IN THE 60S GIVEN MOST DEWPOINTS WHICH MAY
HOLD SOME SPOTS OVER THE SE ABOVE 70.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 1210 PM EDT SUNDAY...
FLAT UPPER RIDGE OVER THE EASTERN U.S. WILL AGAIN BREAK DOWN
THROUGH THE PERIOD WITH PERIODIC S/W ENERGY SPILLING SE AHEAD OF
YET ANOTHER COLD FRONT THAT WILL LEAD TO MORE ERN 5H TROFFINESS
BY THE WEEKEND. TIMING OF FEATURES OFF MODELS WITHIN THIS
TRANSITIONAL PERIOD FROM ZONAL FLOW TO AN EVOLVING BAGGY TROUGH
REGIME WILL REMAIN TRICKY BUT GIVEN HIGH PWATS/HEATING AND UPPER
ENERGY APPEARS THINGS WILL STAY UNSETTLED AHEAD OF THE BOUNDARY.
THIS WOULD BRING DAILY CONVECTIVE CHANCES TO MOST SECTIONS
THU/FRI...WITH FOCUS OVER THE WEST THU AFTERNOON PER AN INIT
WAVE...AND THEN ACROSS THE AREA FRIDAY AHEAD OF THE FRONT WHERE
WILL BE AIDED IN THE EAST BY LEE TROFFINESS. FRONT SHOULD CROSS
THE AREA ON SATURDAY BUT MAY SLOW OVER THE PIEDMONT INTO SATURDAY
NIGHT UNTIL THE 5H TROF SHARPENS/DIGS MORE AND HELPS PUSH IT EAST.
THIS MAY LEAD TO ANOTHER ROUND OF SHOWERS SAT AFTERNOON ESPCLY
EAST WITH DRIER AIR ARRIVING MOST SPOTS BEHIND THE BOUNDARY ON
SUNDAY. VERY WARM TEMPS WITH HIGHS IN THE 80S WEST...TO LOW/MID
90S AHEAD OF THE FRONT THU WILL GET CLIPPED BACK TO 70S/ARND 80
MOUNTAINS...AND LOW/MID 80S EAST BY SUNDAY.
&&
.AVIATION /01Z MONDAY THROUGH FRIDAY/...
AS OF 800 PM EDT SUNDAY
NOT MUCH CHANGE FROM THE PREVIOUS TAF DISCUSSION. VISIBLE SATELLITE
SHOWS A CLEARING TREND ACROSS THE REGION. THE HRRR MODEL SHOWS
LITTLE CLOUD COVER THROUGH THE EVENING. LWB IS THE ONLY LOCATION
EXPECTED TO DROP DOWN TO IFR CIG/VISBYS MONDAY MORNING DUE TO FOG.
PATCHY FOG WILL AFFECT OTHER LOCATIONS AS WELL...HOWEVER AT THIS
POINT ONLY EXPECT MVFR VISBYS AT THE OTHER TAF LOCATIONS. BY 12Z
DAYTIME HEATING WILL ERODE WHATEVER FOG IS LEFT.
BACKED OFF ON THE MENTION OF ANY SHOWERS OR THUNDERSTORMS IN THE
TAFS FOR MONDAY. SOME SHORT WAVE ENERGY SWINGING THROUGH THE
REGION...ALONG WITH A CONTINUED SOUTHERLY FLOW WILL KEEP THE REGION
WARM AND HUMID SO AFTERNOON AND EVENING POP UP SHOWERS AND
THUNDERSTORMS ARE EXPECTED... BUT AT THIS POINT THE ACTIVITY APPEARS
TO BE SCATTERED ENOUGH TO LEAVE ANY MENTION OUT OF ALL LOCATIONS.
.AVIATION EXTENDED...
WE WILL BE TRANSITIONING FROM A FLAT UPPER RIDGE TO A BLOCKY PATTERN
WITH AN EASTERN TROF/WESTERN RIDGE THROUGH THE EXTENDED PERIOD. SFC
HIGH OFF THE EAST COAST WILL KEEP WARM AND MOIST AIR OVER THE REGION
WITH A SERIES OF WAVES RIPPLING THROUGH THE FLOW. THIS WILL
PRIMARILY LEAVE US WITH AN UNSTABLE AIRMASS IN A WEAKLY FORCED
CONVECTIVE ENVIRONMENT THROUGH MIDWEEK. EXPECT A DIURNAL PATTERN OF
CONVECTION WITH VFR IN THE MORNING...THEN MVFR WITH SHRA/TSRA IN THE
AFTERNOON AND EVES...THEN POSSIBLE IFR WITH NOCTURNAL FOG/STRATUS.
WASH...RINSE...REPEAT. LOOKING LIKE LATTER PORTION OF THE WEEK WILL
BE MORE ACTIVE. AS THE PATTERN FINALLY BECOMES MORE AMPLIFIED AND THE
ERN TROF SINKS DOWN INTO THE REGION...IT SHOULD PUSH A COLD FRONT
THROUGH SATURDAY INTO SUNDAY WITH BETTER AVIATION CONDITIONS
THEREAFTER. EXPECT WINDS TO REMAIN ON THE LIGHT SIDE UNTIL THURSDAY
WHEN LOW LEVEL WIND FIELD BEGINS TO INCREASE AS TROF BUILDS DOWN.
&&
.EQUIPMENT...
AS OF 1225 PM EDT SUNDAY...
DANVILLE ASOS VISIBILITY SENSOR REMAINS INOP AND EXPECTED TO BE
FIXED EARLY THIS WEEK.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH/WP
NEAR TERM...RCS
SHORT TERM...JH
LONG TERM...JH
AVIATION...CF/MBS
EQUIPMENT...WP
AREA FORECAST DISCUSSION
NWS SPOKANE WA
815 AM PDT Sat Jun 22 2013
.SYNOPSIS...
Lingering showers from the recent storm system will taper off
today. Temperatures will warm to near normal on Sunday. More wet
and cool weather will arrive on late Sunday and persist through
mid week followed by another warming, dry period to close out the
work-week. Temperatures by the end of the week could be the
hottest of the year so far.
&&
.DISCUSSION...
Updates to the forecast this morning concern the coverage of
showers and thunderstorms this afternoon. Instability this
afternoon is decent, with some guidance showing up to 500 J/kg
CAPE across the northern/eastern mountains (GFS has much less
instability). In addition, satellite imagery shows minor waves
moving down from central BC which could aid the lift. Low level
moisture is plentiful with dew points around 50, so no problem
there. With all this in mind, I`ve increased our chances of rain
for this afternoon/evening across the northern/eastern mountains.
Trajectory of the showers could bring a few of them across the
Spokane/CdA metro area but I`m not confident of thunder there.
The HRRR and 4km WRF show some organized convection moving down
from BC and clipping the WA/BC border this afternoon, which is
where my highest PoPs are. They both show some decent storms, but
keep them north of the border. So this will need to be monitored.
Right now I`m not expecting any strong thunderstorms. RJ
&&
.AVIATION...
12Z TAFS: A weak weather disturbance moving south out of BC will
continue to generate mid level clouds across much of the western
basin into the northern mountains of eastern WA. Farther east
across extreme eastern WA and into the ID Panhandle, early morning
clearing has allowed fog and low stratus to develop in many of the
valleys. This fog (or low stratus) may affect the KGEG, KSFF,
KCOE, KPUW and KLWS TAF sites. Late June sunshine should mix this
out by around 16Z. Scattered showers and isolated thunderstorms
will develop over the mountains of NE WA and N ID this afternoon
and evening but chances are low that this will affect any TAF sites.
/EK
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 70 51 77 55 70 53 / 20 10 0 40 60 70
Coeur d`Alene 69 48 76 55 69 53 / 20 10 10 20 60 70
Pullman 70 47 77 53 69 53 / 10 0 0 40 60 60
Lewiston 78 54 83 57 75 56 / 0 0 0 40 50 60
Colville 75 48 79 56 72 56 / 60 50 10 20 60 70
Sandpoint 69 45 76 54 69 54 / 30 30 10 20 70 80
Kellogg 66 48 74 54 67 53 / 20 20 10 20 70 70
Moses Lake 80 53 82 58 75 55 / 0 0 10 40 50 40
Wenatchee 80 57 80 58 74 54 / 0 0 10 50 60 40
Omak 79 54 80 57 73 56 / 10 10 10 40 60 60
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS GREEN BAY WI
955 PM CDT SUN JUN 23 2013
NEW INFORMATION ADDED TO UPDATE SECTION
.UPDATE...
ISSUED AT 943 PM CDT SUN JUN 23 2013
HAVE REMOVED PCPN CHANCES FOR THE REST OF TONIGHT. DAYTIME INSTABILITY
HAS WANED AND CONVERGENCE ALONG THE BOUNDARY THAT BISECTS THE CWA FROM
NE TO SW (SEE DEW POINT GRADIENT) HAS WEAKENED. 850 MB FLOW IS EXPECTED
TO CONTINUE TO VEER WEST OVERNIGHT...WHICH WILL BRING DRIER AIR INTO
THE REGION. PRECIPITABLE WATER ON THE MPX RAOB DROPPED FROM 1.72 INCH
AT 12Z TO 0.77 INCH AT 00Z.
DISTURBANCE OVER NORTHEAST COLORADO IS EXPECTED TO LIFT NE TOWARD WI
BY MONDAY EVENING. THE LLJ IS ALSO EXPECTED TO BACK SW AND INCREASE
UPSTREAM OF THE REGION...SO PCPN CHANCES SHOULD INCREASE AGAIN
TOMORROW NIGHT.
&&
.SHORT TERM...TONIGHT AND MONDAY
ISSUED AT 252 PM CDT SUN JUN 23 2013
THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A SURFACE
WARM FRONT HAS MOVED THROUGH MOST OF WISCONSIN EXCEPT FOR FAR
NORTHEAST WISCONSIN EARLY THIS AFTERNOON. SOME REMNANT STORMS FROM
AN EARLIER LINE OF CONVECTION ARE MOVING ACROSS SOUTHERN
WISCONSIN...BUT STARTING TO SEE SIGNS OF BEEFY CU DEVELOPING FARTHER
NORTH FROM WAUSHARA COUNTY TO THE WESTERN UPPER PENINSULA. THIS IS
IN A REGION OF BUILDING ML CAPES FROM 1000-1400 J/KG. STILL PLENTY
OF TIME FOR FURTHER DESTABILIZATION TO OCCUR...WITH LIFT VIA
SHORTWAVE OVER NORTHWEST WISCONSIN. AM STILL EXPECTING STORMS TO
FIRE THOUGH IT MAY STILL HAVE A COUPLE HOURS TO GO. ACTUAL FRONT
LIES ACROSS EASTERN MINNESOTA AND CLEARING SKIES ARE MOVING INTO
SOUTHWEST MINNESOTA. IMPACTS FROM CONVECTION ARE THE MAIN FORECAST
CONCERN IN THE SHORT TERM.
TONIGHT..SHORTWAVE OVER NORTHWEST WISCONSIN WILL LIFT NORTHEAST AND
CLEAR NORTHEAST WISCONSIN IN THE EVENING. FORCING ALONG THE TAIL OF
THIS VORT AND FURTHER DESTABILIZATION SHOULD ALLOW SCT STORMS TO
MOVE ACROSS NORTHEAST WISCONSIN IN THE EVENING. WINDS AT 700MB ARE
PRETTY STRONG AT 45 TO 50 KTS...SO ANY STORMS WILL HAVE POTENTIAL AT
CREATING DAMAGING WIND GUSTS AND SMALL HAIL. LOSS OF HEATING AND
EXITING OF THE TAIL OF THE VORT SHOULD LET THE CONVECTION DIMINISH
AND/OR EXIT BY MID TO LATE EVENING. ACTUAL SURFACE FRONT WILL DROP
INTO NORTH-CENTRAL WISCONSIN AFTER MIDNIGHT. CONVERGENCE ALONG THE
FRONT IS VERY WEAK AND THERE IS NO SUPPORT ALOFT...SO COULD SEE SOME
LOW CLOUDS ALONG THE FRONT...MUCH NOT MUCH ELSE. WILL END POPS FROM
NW TO SE AFTER MIDNIGHT. MUGGY LOWS IN THE MID TO UPPER 60S.
MONDAY...SURFACE FRONT WILL STALL ACROSS NORTHERN WISCONSIN IN THE
MORNING. PROGGED SOUNDINGS AND UPSTREAM SATELLITE IMAGERY SHOW
PLENTY OF DRY AIR THROUGH THE COLUMN AND PARTLY TO MOSTLY CLEAR
SKIES. NO CLEAR TRIGGERS UPSTREAM EITHER SO WILL GO WITH A DRY BUT
PARTLY CLOUDY START TO THE DAY. COME AFTERNOON...AN 86/69 PARCEL
OVER THE FOX VALLEY WILL RESULT IN 3000 J/KG OF ML CAPE AND VERY
LITTLE CIN. CONVECTIVE TEMPS ARE IN THE LOW 90S AND DO NOT SEE A
TRIGGER...BUT PERHAPS THE LAKE BREEZE CAN CREATE THE NECESSARY
CONVERGENCE FOR A STORM OR TWO TO POP. WILL KEEP A SLIGHT CHANCE OF
A STORM OVER CENTRAL AND NORTHEAST WISCONSIN WHERE INSTABILITY IS
MAXIMIZED. HIGHS MAINLY IN THE MID 80S.
.LONG TERM...MONDAY NIGHT THROUGH SUNDAY
ISSUED AT 252 PM CDT SUN JUN 23 2013
MEDIUM RANGE MODELS ARE IN GREATER DISAGREEMENT THAN
THE LAST FEW DAYS...ESPECIALLY WITH A POSSIBLE CONVECTIVE COMPLEX
LATE MONDAY NIGHT OR TUESDAY AND AGAIN WEDNESDAY NIGHT WITH THE
POSSIBLE FORMATION OF A CLOSED LOW OVER WISCONSIN OR UPPER
MICHIGAN. AS FAR AS LATE MONDAY NIGHT AND TUESDAY GOES IT LOOKS
LIKE THE GFS IS EXHIBITING SOME SORT OF CONVECTIVE FEEDBACK
PRODUCING A CLOSED UPPER LOW THAT MOVES ACROSS MINNESOTA AND
WISCONSIN PRODUCING CONSIDERABLE CONVECTION. THIS IS LIKELY
OVERDONE AND PREFER THE FLATTER AND SLOWER UPPER SYSTEM THAT SHOULD
BRING SHOWERS AND THUNDERSTORMS TUESDAY AFTERNOON AND EVENING.
THE GFS ALSO FORECASTS A CLOSED UPPER LOW WEDNESDAY NIGHT AND
THURSDAY OVER THE WESTERN GREAT LAKES WHICH SEEMS OVERDONE
CONSIDERING THE CURRENT PATTERN. CANNOT TOTALLY DISCOUNT THE GFS
AS IT HAS SOME SUPPORT FROM THE NAM BUT THE ECMWF IS MUCH FASTER
AND WEAKER. WARM AND HUMID WEATHER EXPECTED THROUGH THURSDAY.
AFTER THURSDAY THE MODELS DO AGREE THAT AN UPPER RIDGE
WILL DEVELOP OVER THE WESTERN UNITED STATES WITH CYCLONIC
NORTHWEST FLOW OVER WISCONSIN. THIS SHOULD BRING COOLER AND DRIER
AIR TO THE REGION BY FRIDAY AND SATURDAY. WHILE IT SHOULD BE
GENERALLY DRY FRIDAY AND SATURDAY THERE COULD BE SCATTERED DIURNAL
SHOWERS WITH COLD TEMPERATURES ALOFT.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 617 PM CDT SUN JUN 23 2013
HARD TO UNDERSTAND WHY STORMS HAVE NOT DEVELOPED THIS AFTERNOON...WITH
PLENTY OF MOISTURE/INSTABILITY AND CONVERGENCE OVER NE/EC WI. GIVEN
THE CURRENT TRENDS...WILL ONLY CARRY A VCTS AT THE GRB TAF SITE FOR
AN HOUR...OTHERWISE DRY. GIVEN THAT THE LOW-LEVEL JET IS EXPECTED
TO WEAKEN AND VEER TO A WESTERLY DIRECTION...CONFIDENCE IN TSTMS IS
TOO LOW TO MENTION FOR THE REST OF THE TAF PERIOD. BEST ESTIMATE
RIGHT NOW IS THAT SOME CONVECTION WILL FIRE MONDAY NIGHT...AS A
WEAK UPPER DISTURBANCE TRACKS THROUGH THE AREA AND A SOUTHWESTERLY
LOW-LEVEL JET REDEVELOPS. MAIN AVIATION CONCERN FOR THIS TAF
PERIOD WOULD APPEAR TO BE FOG POTENTIAL LATE TONIGHT...ALTHOUGH
WILL ONLY MENTION MVFR VSBYS...EXPECT AT RHI WHERE SOME IFR
CONDITIONS MAY OCCUR.
HAVE REMOVED THE MENTION OF LLWS THIS EVENING...AS EARLY DATA FROM
THE GRB RAOB ONLY SHOWED WINDS AROUND 25 KTS JUST OFF THE SURFACE.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE.........KIECKBUSCH
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......KIECKBUSCH
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
904 PM CDT SUN JUN 23 2013
.UPDATE...
THE TRENDS OF THE HRRR ARE ENCOURAGING FOR THE OVERNIGHT HOURS.
THE EARLIER CONVECTION TO THE SOUTH AND ITS EXTENSIVE CLOUD COVER
HAVE HELPED STABILIZE THINGS FOR THE TIME BEING. ALSO...DEEP SHEAR
VALUES REMAIN VERY LOW. CURRENTLY NOT SEEING ANY TRIGGERS TO
SUPPORT ANY WIDESPREAD ELEVATED CONVECTION THROUGH THE OVERNIGHT
HOURS. HOWEVER...JUST CAN/T RULE IT OUT COMPLETELY. OUR NEXT ROUND
OF RAIN SHOULD ARRIVE BY AROUND SUNRISE ON MONDAY. THIS ACTIVITY
IS STARTING TO GET ORGANIZED OVER SOUTHERN IOWA WHERE THE BEST LOW
LEVEL JET INTERACTION IS OCCURRING. THAT/S EXPECTED TO LIFT
NORTHEAST INTO SOUTHERN WISCONSIN DURING THE MORNING. GIVEN THE
HIGH PRECIPITABLE WATER VALUES...WILL KEEP THE FLASH FLOOD WARNING
GOING. ANY STORMS WILL PRODUCE COPIOUS RAINFALL AMOUNTS THAT COULD
CAUSE PROBLEMS ACROSS THE WESTERN FORECAST AREA.
&&
.AVIATION/06Z TAFS/...
GENERALLY EXPECT VFR CONDITIONS THROUGH THE PERIOD. ONLY
EXCEPTIONS ARE THE POTENTIAL FOR SOME MVFR VSBYS DUE TO FOG LATE
TONIGHT INTO MONDAY MORNING. THE OTHER IS THE POTENTIAL FOR BRIEF
MVFR CONDITIONS IN AND AROUND THUNDERSTORMS. BELIEVE ANY
THUNDERSTORM CHANCES WILL HOLD OFF UNTIL AFTER 15Z AT ALL THE TAF
SITES...THEN WE COULD SEE STORMS ON AND OFF DURING THE DAY ON
MONDAY...DIMINISHING BY EVENING.
&&
.PREV DISCUSSION... /ISSUED 341 PM CDT SUN JUN 23 2013/
VERY SHORT TERM...TONIGHT AND MONDAY.
TONIGHT - CONFIDENCE...LOW
SURFACE/UPPER LOW LIFTING NORTH FROM NORTH DAKOTA. ONGOING
CONVECTION DRIVEN BY OUTFLOW AHEAD OF DECAYING IOWA COMPLEX. NICE
LINE MAINLY SOUTH OF THE BORDER WILL SHIFT EAST LATE THIS AFTERNOON
SETTING UP A DRY EVENING FOR A WHILE. TRENDS IN HRRR SUGGEST
ACTIVITY WILL RE-FIRE LATER TONIGHT WITH ARRIVAL OF A RENEWED 850
MILLIBAR JET LET. HOWEVER NOW LATCHING ONTO THE MISSOURI COMPLEX THIS
RENEWED DEVELOPMENT SKEWED FURTHER SOUTHWEST INTO IOWA. THE 12Z SPC
4KM WRF ALSO SHOWS POTENTIAL FOR REDEVELOPMENT WITH THE 850
JET...AND WOULD FAVOR A MORE NORTHERN SOLUTION. IN ADDITION MODELS
SHOW SOME DIVERGENCE WITH RIGHT REAR QUADRANT OF 250-300 MILLIBAR
JET MAX TRAVERSING THE NORTHERN LAKES. REALLY CONCERNED THAT MISSOURI
COMPLEX MAY STEAL OUR THUNDER BY DISRUPTING RETURN OOMPH OF LLJ THIS
FAR NORTH. WILL HAVE TO WAIT AND SEE ON THIS. AFTER COLLABORATING
WITH NEIGHBORS CONSENSUS IS TO HOLD ON TO THE WATCH. MODEL TRENDS
NOT SUGGESTING TRAINING TYPE REDEVELOPMENT SHOULD IT OCCUR...BUT
RATHER SCATTERED TYPE SHRA/TSRA...AND IT MAY ARRIVE VERY LATE.
GIVEN THE HEAVY AMOUNT OF RAIN THAT HAS ALREADY FALLEN IN THE WATCH
AREA WE WON/T NEED A TEXTBOOK FLASH FLOOD SETUP TO LEAD TO POSSIBLE
ISSUES WITH FLOODING. SO WILL HANG ONTO THE WATCH FOR NOW...BUT
GIVEN MODEL VARIATION WITH WHERE LATER DEVELOPMENT OCCURS CONFIDENCE
IN CONVECTIVE TRENDS NOT THE GREATEST.
MONDAY - CONFIDENCE...LOW TO MEDIUM
SOME SUGGESTION THAT THE MORNING 850 JET PEELS OFF AND SETS UP A
LULL IN CONVECTION WITH WEAK RIDGING. GFS AND ECMWF SHOW
REDEVELOPMENT ACROSS THE CWA DURING THE AFTERNOON WHILE THE NAM AND
GEM SHOW A DRIER LOOK. THE GFS IS SHOWING A FAIRLY SIGNIFICANT SURGE
IN THE 850 JET DURING THE AFTERNOON WHILE OTHER MODELS SUGGEST FOCUS
WILL BE FURTHER WEST. PLENTY OF MOISTURE AVAILABLE SO KEEPING THE
FLASH FLOOD WATCH IN PLACE SEEMS THE BEST WAY TO GO AT THIS POINT.
SHORT TERM...MONDAY NIGHT THROUGH WEDNESDAY. FORECAST CONFIDENCE
LOW TO MEDIUM.
WEAK RIDGING BETWEEN ONTARIO SHORT WAVE PUSHING TO THE EAST AND
AHEAD OF NEXT SHORT WAVE CROSSING THE NORTHERN INTERMOUNTAIN REGION
INTO THE NORTHERN PLAINS THAT REACHES WESTERN GREAT LAKES BY
WEDNESDAY MORNING.
COULD BE ONGOING CONVECTION MONDAY EVENING WITH 850 MB WAA/MOISTURE
ADVECTION AND WEAK PERTURBATIONS/MCVS THAT ALL MODELS SHOW AT
DIFFERING TIMES/STRENGTHS FROM MONDAY NIGHT INTO TUESDAY. GFS LOOKS
OVERDONE WITH DEEP LAYER MESOLOW CROSSING CENTRAL WI DURING THE
OVERNIGHT AND WILL BE IGNORED. BEST CHANCES FOR SEEING AN MCS IS
WESTERN CWA AS IT MAY TRACK WITH LOW-LEVEL JET AS IT FOCUSES ON SW
WI AS IT VEERS FROM SOUTH TO SOUTHWEST AROUND 06Z. LIKELY POPS IN
THE WEST TAPERING TO CHANCE IN THE EAST. WHILE PW/S NOT AS ROBUST AS
THE PAST FEW DAYS...STILL 1.3 INCHES TO 1.5 INCHES OR AROUND 135% OF
NORMAL. WILL HAVE TO CONTINUE TO WATCH SATURATED WESTERN CWA FOR
FLASH FLOODING POTENTIAL.
WITH LEE SURFACE CYCLOGENESIS OVER THE PLAINS AHEAD OF SHORT WAVE
TROUGH AND BROAD AREA OF HIGH PRESSURE OVER THE SE U.S. REGION
REMAINS IN THE WARM SECTOR ON SOUTHEASTERN SIDE OF FAIRLY STATIONARY
SURFACE TROUGH WITH A STEADY SSW FEED OF MOIST UNSTABLE AIR INTO THE
REGION. NEXT LOW-LEVEL JET MAX APPROACHES TUE EVENING...WITH 12Z NAM
TAKING DEAD AIM AT SRN WI WHILE GFS MORE SRLY AND FOCUSED ON MN/IA
THEN VEERING TOWARD WI OVERNIGHT AND WEAKENING. WILL HAVE LIKELY
POPS EVERYWHERE TUESDAY NIGHT...WITH CHANCE POPS WEDNESDAY AS TROUGH
MOVES THROUGH.
LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY. FORECAST CONFIDENCE
MEDIUM.
EVOLUTION FROM NEAR-ZONAL FLOW TO A MORE AMPLIFIED PATTERN BEGINS AS
WEDNESDAY SHORT WAVE TROUGH IS FOLLOWED BY A DIGGING TROUGH THAT
DROPS INTO THE UPPER GREAT LAKES. GFS MUCH DEEPER AND COLDER THAN
ECMWF. STREAM OF VORTICITY MAXIMA THROUGH THE REGION KEEPS CHANCE
POPS IN THE FORECAST DURING THIS TRANSITION.
UPPER GREAT LAKES WILL BE IN NW FLOW BETWEEN THE DEEPENING ERN U.S.
TROUGH AND A BROAD AMPLIFYING RIDGE OVER THE WEST BRINGING COOLER
TEMPERATURES CLOSER TO NORMAL FOR THE END OF THE WEEK INTO THE
WEEKEND.
AVIATION/00Z TAFS/...LINE OF CONVECTION FROM EXTREME SRN WI INTO IL
WILL SHIFT EAST OF THE TAF SITES LATE THIS AFTN. EXPECTING LATE
NIGHT REDEVELOPMENT WITH 850 MILLIBAR JET BEING THE PRIMARY FOCUS.
THIS ACTIVITY PROGGD TO AFFECT THE AREA INTO MONDAY MORNING WITH
PERHAPS A LULL DEVELOPING LATE MORNING INTO EARLY AFTERNOON.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...FLASH FLOOD WATCH THROUGH MONDAY EVENING FOR WIZ046-047-056-057-
062-063-067>069.
LM...NONE.
&&
$$
UPDATE...DAVIS
TONIGHT/MONDAY AND AVIATION/MARINE...COLLAR
MONDAY NIGHT THROUGH SUNDAY...REM
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
627 PM CDT SUN JUN 23 2013
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND MONDAY
ISSUED AT 252 PM CDT SUN JUN 23 2013
THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A SURFACE
WARM FRONT HAS MOVED THROUGH MOST OF WISCONSIN EXCEPT FOR FAR
NORTHEAST WISCONSIN EARLY THIS AFTERNOON. SOME REMNANT STORMS FROM
AN EARLIER LINE OF CONVECTION ARE MOVING ACROSS SOUTHERN
WISCONSIN...BUT STARTING TO SEE SIGNS OF BEEFY CU DEVELOPING FARTHER
NORTH FROM WAUSHARA COUNTY TO THE WESTERN UPPER PENINSULA. THIS IS
IN A REGION OF BUILDING ML CAPES FROM 1000-1400 J/KG. STILL PLENTY
OF TIME FOR FURTHER DESTABILIZATION TO OCCUR...WITH LIFT VIA
SHORTWAVE OVER NORTHWEST WISCONSIN. AM STILL EXPECTING STORMS TO
FIRE THOUGH IT MAY STILL HAVE A COUPLE HOURS TO GO. ACTUAL FRONT
LIES ACROSS EASTERN MINNESOTA AND CLEARING SKIES ARE MOVING INTO
SOUTHWEST MINNESOTA. IMPACTS FROM CONVECTION ARE THE MAIN FORECAST
CONCERN IN THE SHORT TERM.
TONIGHT..SHORTWAVE OVER NORTHWEST WISCONSIN WILL LIFT NORTHEAST AND
CLEAR NORTHEAST WISCONSIN IN THE EVENING. FORCING ALONG THE TAIL OF
THIS VORT AND FURTHER DESTABILIZATION SHOULD ALLOW SCT STORMS TO
MOVE ACROSS NORTHEAST WISCONSIN IN THE EVENING. WINDS AT 700MB ARE
PRETTY STRONG AT 45 TO 50 KTS...SO ANY STORMS WILL HAVE POTENTIAL AT
CREATING DAMAGING WIND GUSTS AND SMALL HAIL. LOSS OF HEATING AND
EXITING OF THE TAIL OF THE VORT SHOULD LET THE CONVECTION DIMINISH
AND/OR EXIT BY MID TO LATE EVENING. ACTUAL SURFACE FRONT WILL DROP
INTO NORTH-CENTRAL WISCONSIN AFTER MIDNIGHT. CONVERGENCE ALONG THE
FRONT IS VERY WEAK AND THERE IS NO SUPPORT ALOFT...SO COULD SEE SOME
LOW CLOUDS ALONG THE FRONT...MUCH NOT MUCH ELSE. WILL END POPS FROM
NW TO SE AFTER MIDNIGHT. MUGGY LOWS IN THE MID TO UPPER 60S.
MONDAY...SURFACE FRONT WILL STALL ACROSS NORTHERN WISCONSIN IN THE
MORNING. PROGGED SOUNDINGS AND UPSTREAM SATELLITE IMAGERY SHOW
PLENTY OF DRY AIR THROUGH THE COLUMN AND PARTLY TO MOSTLY CLEAR
SKIES. NO CLEAR TRIGGERS UPSTREAM EITHER SO WILL GO WITH A DRY BUT
PARTLY CLOUDY START TO THE DAY. COME AFTERNOON...AN 86/69 PARCEL
OVER THE FOX VALLEY WILL RESULT IN 3000 J/KG OF ML CAPE AND VERY
LITTLE CIN. CONVECTIVE TEMPS ARE IN THE LOW 90S AND DO NOT SEE A
TRIGGER...BUT PERHAPS THE LAKE BREEZE CAN CREATE THE NECESSARY
CONVERGENCE FOR A STORM OR TWO TO POP. WILL KEEP A SLIGHT CHANCE OF
A STORM OVER CENTRAL AND NORTHEAST WISCONSIN WHERE INSTABILITY IS
MAXIMIZED. HIGHS MAINLY IN THE MID 80S.
.LONG TERM...MONDAY NIGHT THROUGH SUNDAY
ISSUED AT 252 PM CDT SUN JUN 23 2013
MEDIUM RANGE MODELS ARE IN GREATER DISAGREEMENT THAN
THE LAST FEW DAYS...ESPECIALLY WITH A POSSIBLE CONVECTIVE COMPLEX
LATE MONDAY NIGHT OR TUESDAY AND AGAIN WEDNESDAY NIGHT WITH THE
POSSIBLE FORMATION OF A CLOSED LOW OVER WISCONSIN OR UPPER
MICHIGAN. AS FAR AS LATE MONDAY NIGHT AND TUESDAY GOES IT LOOKS
LIKE THE GFS IS EXHIBITING SOME SORT OF CONVECTIVE FEEDBACK
PRODUCING A CLOSED UPPER LOW THAT MOVES ACROSS MINNESOTA AND
WISCONSIN PRODUCING CONSIDERABLE CONVECTION. THIS IS LIKELY
OVERDONE AND PREFER THE FLATTER AND SLOWER UPPER SYSTEM THAT SHOULD
BRING SHOWERS AND THUNDERSTORMS TUESDAY AFTERNOON AND EVENING.
THE GFS ALSO FORECASTS A CLOSED UPPER LOW WEDNESDAY NIGHT AND
THURSDAY OVER THE WESTERN GREAT LAKES WHICH SEEMS OVERDONE
CONSIDERING THE CURRENT PATTERN. CANNOT TOTALLY DISCOUNT THE GFS
AS IT HAS SOME SUPPORT FROM THE NAM BUT THE ECMWF IS MUCH FASTER
AND WEAKER. WARM AND HUMID WEATHER EXPECTED THROUGH THURSDAY.
AFTER THURSDAY THE MODELS DO AGREE THAT AN UPPER RIDGE
WILL DEVELOP OVER THE WESTERN UNITED STATES WITH CYCLONIC
NORTHWEST FLOW OVER WISCONSIN. THIS SHOULD BRING COOLER AND DRIER
AIR TO THE REGION BY FRIDAY AND SATURDAY. WHILE IT SHOULD BE
GENERALLY DRY FRIDAY AND SATURDAY THERE COULD BE SCATTERED DIURNAL
SHOWERS WITH COLD TEMPERATURES ALOFT.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 617 PM CDT SUN JUN 23 2013
HARD TO UNDERSTAND WHY STORMS HAVE NOT DEVELOPED THIS AFTERNOON...WITH
PLENTY OF MOISTURE/INSTABILITY AND CONVERGENCE OVER NE/EC WI. GIVEN
THE CURRENT TRENDS...WILL ONLY CARRY A VCTS AT THE GRB TAF SITE FOR
AN HOUR...OTHERWISE DRY. GIVEN THAT THE LOW-LEVEL JET IS EXPECTED
TO WEAKEN AND VEER TO A WESTERLY DIRECTION...CONFIDENCE IN TSTMS IS
TOO LOW TO MENTION FOR THE REST OF THE TAF PERIOD. BEST ESTIMATE
RIGHT NOW IS THAT SOME CONVECTION WILL FIRE MONDAY NIGHT...AS A
WEAK UPPER DISTURBANCE TRACKS THROUGH THE AREA AND A SOUTHWESTERLY
LOW-LEVEL JET REDEVELOPS. MAIN AVIATION CONCERN FOR THIS TAF
PERIOD WOULD APPEAR TO BE FOG POTENTIAL LATE TONIGHT...ALTHOUGH
WILL ONLY MENTION MVFR VSBYS...EXPECT AT RHI WHERE SOME IFR
CONDITIONS MAY OCCUR.
HAVE REMOVED THE MENTION OF LLWS THIS EVENING...AS EARLY DATA FROM
THE GRB RAOB ONLY SHOWED WINDS AROUND 25 KTS JUST OFF THE SURFACE.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......KIECKBUSCH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
358 PM CDT SAT JUN 22 2013
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 253 PM CDT SAT JUN 22 2013
AT 3 PM...A WARM FRONT WAS LOCATED NEAR THE INTERSTATE 94 CORRIDOR
AND AN OUTFLOW BOUNDARY OVER NORTHERN IOWA. AS THE TEMPERATURES
RISE ABOVE THE CONVECTIVE TEMPERATURES /LOWER 80S/ LATE THIS
AFTERNOON...EXPECT SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP
ALONG AND SOUTH OF THE INTERSTATE 94 CORRIDOR. IN ADDITION...
EXPECT THE SYSTEM MOVING OUT OF NORTHWEST IOWA TO GRADUALLY
UPSCALE AS IT MOVES INTO BETTER CAPES AND MOISTURE TRANSPORT. WITH
0-3 KM SHEAR GREATER THAN 40 KNOTS...THINKING THAT THE STORMS
BECOME MORE COLD POOL DOMINATED THAT THERE WILL ONCE AGAIN BE THE
POTENTIAL FOR SOME BOW ECHOS TO DEVELOP LATE THIS AFTERNOON AND
EVENING. IN ADDITION...WITH 1000 TO 1200 J/KG DCAPES THERE WILL
BE THE POTENTIAL FOR DAMAGING WET MICROBURSTS. WITH PRECIPITABLE
WATER VALUES RUNNING BETWEEN 1.8 AND 2.0 INCHES AND WARM CLOUDS
DEPTHS BETWEEN 4 AND 4.5 KM...EXPECT THE THUNDERSTORMS TO BE VERY
EFFECTIVE RAIN PRODUCERS. HOWEVER IT LOOKS LIKE THEY WILL BE
PROGRESSIVELY MOVING WHICH WILL LIMIT THE THREAT FOR WIDESPREAD FLASH
FLOODING. HOWEVER WITH THIS SAID...WILL STILL HAVE TO WATCH
URBANIZED AREAS WHERE JUST AN INCH OF RAIN AN HOUR CAN RESULT IN
SOME LOCALIZED FLASH FLOODING.
FOR OVERNIGHT...THE 23.12Z DETERMINISTIC MODELS CONTINUE TO SHOW
THAT MUCH OF THE PRECIPITATION FOR THIS TIME PERIOD WILL BE MAINLY
NORTH OF THE INTERSTATE 90 CORRIDOR. THEY HAVE SHOWED THIS FOR THE
PAST 6 MODEL CYCLES. THIS IS IN RESPONSE TO THE TROUGH CURRENTLY
OVER NEBRASKA MOVING NORTHEAST AWAY FROM THE FORECAST AREA. AS
THIS OCCURS...THE NOSE OF THE 850 MB MOISTURE TRANSPORT WILL PUSH
NORTH INTO NORTHERN WISCONSIN. IN THE WAKE OF THIS TROUGH...THE
PRECIPITABLE WATER VALUES DROP TO 1.2 TO 1.4 INCHES...AND THE WARM
CLOUD LAYER DEPTHS FALL INTO THE 3.5 TO 4 KM RANGE. THIS IS IDEA
THAT THE PRECIPITATION COULD BEGIN WANING OVERNIGHT IS SUPPORTED
BY THE LAST 2 RUNS OF THE HRRR WHICH SHOWS A BAND OF SHOWERS
AND THUNDERSTORMS PROGRESSIVELY MOVING NORTHEAST THROUGH CLARK AND
TAYLOR COUNTIES IN NORTH CENTRAL WISCONSIN BETWEEN 23.07Z AND 23.09Z.
FOR SUNDAY AFTERNOON...EXPECT THE UPPER LEVEL TROUGH WHICH HAS
BEEN POSITIONED TO OUR WEST OVER THE LAST SEVERAL DAYS TO MOVE
INTO THE WESTERN PORTIONS OF THE FORECAST AREA. WHILE THE 850 MB
MOISTURE TRANSPORT IS NOT THAT IMPRESSIVE. PRECIPITABLE WATER
VALUES DO CLIMB TO AROUND 1.8 INCHES...WARM CLOUD LAYER DEPTHS
CLIMB ABOVE 4 KM...AND CORFIDI VECTORS SUGGEST TRAINING ALONG AND
AHEAD OF THE COLD FRONT. AS A RESULT...WILL HAVE TO WATCH FOR THE
POTENTIAL FOR SOME FLOODING. CERTAINTY ON THE SPEED AND LOCATION
OF THIS FRONT WAS NOT HIGH ENOUGH TO GO WITH A FLASH FLOOD WATCH
AT THIS TIME.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 253 PM CDT SAT JUN 22 2013
ON SUNDAY NIGHT AND MONDAY...THE MODELS CONTINUE TO SHOW THAT A SHORT
WAVE TROUGH WILL MOVE ACROSS WESTERN AND NORTHERN MINNESOTA. AS
THIS OCCURS...EXPECT A COLD FRONT TO MOVE THROUGH THE REGION. THIS
FRONT WILL BE THE FOCUS FOR ADDITIONAL SHOWER AND THUNDERSTORM
ACTIVITY. IT MAY MOVE FAR ENOUGH EAST TO ALLOW SOME DRYING ON
MONDAY AFTERNOON.
FROM MONDAY NIGHT THROUGH WEDNESDAY...THE MODELS CONTINUE TO SHOW
THAT A STATIONARY FRONT WILL LINGER ACROSS THE AREA. WHILE THE
MODELS HAVE CONSISTENTLY SHOWED THIS...THEY CONTINUE TO STRUGGLE
ON THE LOCATION AND TIMING OF THUNDERSTORM COMPLEXES WHICH MOVE
THROUGH THE REGION...SO JUST WENT WITH THE ALL BLEND TEMPERATURES
AND PRECIPITATION CHANCES.
FOR THE REMAINDER OF THIS TIME PERIOD...IT CONTINUES TO LOOK LIKE
THE UPPER LEVEL RIDGE WILL RETROGRADE WEST INTO THE WESTERN UNITED
STATES. THIS WOULD PLACE THE AREA UNDER NORTHWEST FLOW ALOFT. AS
A RESULT...EXPECT NEAR TO SLIGHTLY BELOW-NORMAL TEMPERATURES.
PRECIPITATION CHANCES ARE NOT CLEAR AS THERE WILL THE POTENTIAL
FOR SHORT WAVE TROUGHS TO MOVE SOUTHEAST THROUGH THE AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1248 PM CDT SAT JUN 22 2013
EXPECTING SCATTERED THUNDERSTORMS TO FIRE THIS AFTERNOON ALONG A
WARM FRONT SITUATED ALONG THE IA/MN BORDER. PLAN ON THE BULK OF THIS
THUNDERSTORM ACTIVITY TO EXTEND FROM KFSD THROUGH SOUTH-CENTRAL
MN...WITH EASTERN FRINGES OF THIS CONVECTION REACHING TOWARD THE
MISSISSIPPI RIVER INCLUDING KRST/KLSE TAF SITES. THE WARM FRONT IS
EXPECTED TO PUSH NORTH OF THE AREA AFTER MIDNIGHT...TAKING THE
THUNDERSTORM ACTIVITY WITH IT. BOTTOM LINE...INCLUDED VCTS BKN030-035CB
IN THE KRST/KLSE TAFS FROM 21Z THROUGH 06Z. OTHER THAN SOME 6SM
BR IN THE 08-13Z TIME FRAME...EXPECTING VFR CONDITIONS THEN TO
PREVAIL THROUGH 18Z SUNDAY. SHRA/TS LOOKING LIKELY AGAIN SUNDAY
AFTERNOON/EVENING AS A COLD FRONT PUSHES EAST OUT OF THE NORTHERN
PLAINS TOWARD THE AREA.
&&
.HYDROLOGY...
ISSUED AT 253 PM CDT SAT JUN 22 2013
HYDRO CONCERNS LINGER ACROSS TURKEY...UPPER IOWA...SOUTHERN HALF OF
THE KICKAPOO...BLACK...AND TURTLE CREEK. IN ADDITION...THE SMALL
STREAMS ACROSS ALLAMAKEE AND CLAYTON COUNTIES IN NORTHEAST IOWA...
AND CRAWFORD AND GRANT COUNTIES IN SOUTHWEST WISCONSIN.
FORTUNATELY IT LOOKS LIKE THE HEAVIEST RAIN POTENTIAL FOR TONIGHT
WILL BE MAINLY NORTH OF MOST OF THESE BASINS. HOWEVER THERE IS
CONCERN ON SUNDAY THAT THERE COULD BE ANOTHER ROUND OF HEAVY RAIN
THAT COULD AFFECT THE AREA ON SUNDAY AFTERNOON AND NIGHT. HOWEVER
DUE TO THE UNCERTAINTY ON THE SPEED OF THIS SYSTEM...RAINFALL
AMOUNTS ARE NOT CLEAR.
IN ADDITION TO THE SHORT TERM WATER CONCERNS...THERE IS A RIVER
FLOOD WATCH FOR THE MISSISSIPPI AT WABASHA...WINONA...AND
LA CROSSE. THESE RIVERS ARE EXPECTED TO GO ABOVE FLOOD STAGE UNTIL
AFTER JULY 1ST.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...DAS
HYDROLOGY...BOYNE
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 246 PM CDT SAT JUN 22 2013
THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A
COMPLICATED WEATHER MAP THIS AFTERNOON ACROSS THE REGION. OUTFLOW
BOUNDARY FROM LAST NIGHTS STORMS REACHED INTO CENTRAL ILLINOIS AND
CENTRAL IOWA...BUT IS NOW RETURNING NORTHWARD INTO SOUTHERN
MINNESOTA. MEANWHILE...HIGH PRESSURE OVER ONTARIO IS PUSHING A WEAK
CANADIAN FRONT INTO CENTRAL WISCONSIN AND CENTRAL MINNESOTA.
LOOKING ALOFT...VARIOUS SHORTWAVE TROUGHS ARE PROGRESSING NORTHEAST
OVER THE NORTHERN MISSISSIPPI VALLEY AND THE UPPER PENINSULA. RADAR
IS PRETTY QUIET ACROSS THE REGION SO FAR THIS AFTERNOON...BUT THE
ATMOSPHERE IS STILL RECOVERING FROM LAST NIGHTS CONVECTION.
INSTABILITY IS BEGINNING TO BUILD OVER SOUTHERN MINNESOTA IN CLOSE
PROXIMITY TO THE RETURNING OUTFLOW BOUNDARY. LOW LEVEL CONVERGENCE
IS MAXIMIZED HERE...SO THIS BOUNDARY LOOKS TO BE THE FOCUS FOR THE
REST OF THE AFTERNOON AND HEADING INTO THE EVENING.
OBVIOUSLY...IMPACTS FROM POSSIBLE CONVECTION IS THE MAIN FORECAST
CONCERN IN THE SHORT TERM.
TONIGHT...THE LLJ WILL DEVELOP AGAIN AHEAD OF SHORTWAVE TROUGHS
EXTENDING FROM THE CENTRAL GREAT PLAINS TO LAKE SUPERIOR.
NAM/RUC/GFS SUGGEST MASS CONVERGENCE ALONG THE NOSE OF THE LLJ WILL
TAKE PLACE ACROSS CENTRAL OR SOUTHERN MINNESOTA...AND INTO WESTERN
WISCONSIN WHERE THE RETURNING OUTFLOW BOUNDARY/WARM FRONT WILL
RESIDE. AS INCREASING FLOW LIFTS OVER THIS BOUNDARY IN CONJUNCTION
WITH ELEVATED INSTABILITY OF 1000-2000 J/KG...ANTICIPATE ANOTHER MCS
TO DEVELOP OVER CENTRAL OR SOUTHERN MINNESOTA THIS EVENING BEFORE
TRACKING EAST ALONG THE BOUNDARY. THINK INSTABILITY WILL HAVE
RECOVERED ENOUGH BY THIS EVENING FOR ANY CONVECTION TO REACH CENTRAL
WISCONSIN OR EVEN THE FOX VALLEY BEFORE IT TURNS TO THE SOUTHEAST
LATE TONIGHT. LATEST MODELS ARE GENERALLY ALL OVER THE PLACE WITH
PRECIP TRENDS...SO CONFIDENCE IS RATHER LOW. BUT THE FRONT HAS BEEN
ACTIVE WITH MCS/S THE PAST SEVERAL NIGHTS...SO AS LONG AS
INSTABILITY DEVELOPS ALONG THE BOUNDARY THIS AFTERNOON...CANNOT RULE
OUT THE POSSIBILITY OF AN MCS DEVELOPING THIS EVENING. BIGGEST
THREAT WOULD BE HEAVY RAINFALL/FLOODING...BUT STRONG STRAIGHT LINE
WINDS AND SMALL HAIL COULD ALSO OCCUR IF INSTABILITY RECOVERS
ENOUGH. LOWS MAINLY IN THE 60S.
SUNDAY...MUCH OF THE DETAILS REVOLVE AROUND WHAT HAPPENS
TONIGHT...AND IF CONVECTION CAN LAY OUT ANOTHER OUTFLOW BOUNDARY
WHICH KEEPS THE REGION STABLE FOR MUCH OF THE DAY. IF THIS
OCCURS...MUCH OF THE MORNING INTO EARLY AFTERNOON MAY TURN OUT TO
BE DRY. DURING THE AFTERNOON THOUGH...A SHORTWAVE TROUGH MOVING
INTO NORTHWEST WISCONSIN WILL HELP SOUTHERLY FLOW STRENGTHEN AND
PUSH INSTABILITY NORTHWARD. REALLY TOUGH TO SAY HOW MUCH
INSTABILITY WILL BE PRESENT...DUE TO UNCERTAINTIES IN
HEATING...AND ALSO PROGGED SOUNDINGS APPEAR TO BE CONVECTIVELY
ADJUSTED. BUT WITH WIND FIELDS STRENGTHENING TOMORROW...FAIRLY
UNIDIRECTIONAL SHEAR CALLS FOR DAMAGING WINDS AND LARGE HAIL AS
THE MAIN THREATS. CENTRAL AND NORTH-CENTRAL WISCONSIN SHOULD HAVE
THE BEST CHANCE OF STORMS TOMORROW AFTERNOON AND WILL KEEP THE
HIGHEST POPS OVER THERE. WITH SOUTHERLY WINDS...TEMPS SHOULD REACH
MOSTLY IN THE MID TO UPPER 80S...PERHAPS A LITTLE LOWER OVER N-C
WISCONSIN.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 246 PM CDT SAT JUN 22 2013
SOUTHWEST UPPER FLOW AND SEVERAL WEAK FRONTAL BOUNDARIES WILL
KEEP THE THREAT OF PRECIPITATION IN THE FORECAST THROUGH THE
MIDDLE OF THE WEEK. A WEAK COLD FRONT WILL MOVE THROUGH SUNDAY
NIGHT AND SHOULD BE ACCOMPANIED WITH SHOWERS AND THUNDERSTORMS.
THERE COULD BE A BREAK IN THE ACTION MONDAY BEFORE THE FRONT LIFTS
SLOWLY NORTH AND PERHAPS STALL OVER THE FORECAST AREA TUESDAY AND
WEDNESDAY. A MORE SIGNIFICANT COLD FRONT SHOULD MOVE THROUGH
THURSDAY AND BE FOLLOWED BY DRY AND PLEASANT WEATHER FOR THE END
OF THE WEEK.
THERE ARE THREATS OF SEVERE THUNDERSTORMS MONDAY THROUGH WEDNESDAY
AFTERNOONS WITH HIGH CAPES AND MODERATE MID LEVEL WINDS. HIGH
PRECIPITABLE WATER VALUES AND SLOW MOVING STORMS ALSO COULD
PRODUCE EXCESSIVE RAINS. WILL MENTION IN THE HAZARDOUS WEATHER
OUTLOOK.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1236 PM CDT SAT JUN 22 2013
CONFIDENCE HAS NOT IMPROVED ANY IN THE FORECAST DETAILS OVER THE
NEXT 24 HOURS. PARTIAL CLEARING OCCURRING IN THE VICINITY OF
VARIOUS SHORTWAVE TROUGHS OVER MINNESOTA AND WESTERN WISCONSIN SUGGESTS
POTENTIAL FOR STORMS WILL INCREASE LATER THIS AFTERNOON IF THESE
TRENDS CONTINUE. IF STORMS DEVELOP...WOULD LIKELY IMPACT CENTRAL
AND NORTH-CENTRAL WISCONSIN. NOCTURNAL STORMS COULD ALSO REFIRE
ALONG A WARM FRONT AS IT LIFTS NORTH OVER MINNESOTA AND WISCONSIN
TONIGHT. IF THIS OCCURS...STORMS WOULD TRACK ALONG THE WARM FRONT
EAST-SOUTHEAST INTO NORTH-CENTRAL WISCONSIN AND POSSIBLY NORTHEAST
WISCONSIN LATE. UNCERTAINTIES REVOLVING AROUND LOCATION AND TIMING
OF STORMS IS TOO HIGH TO INCLUDE TSRA IN TAFS AT THIS TIME.
OTHERWISE...CIGS IMPROVING THIS AFTERNOON TO VFR.
&&
.MARINE...DENSE FOG IS THE PRIMARY CONCERN OVER LAKE MICHIGAN AS
WARM AND MOOIST AIR FLOWS NORTH OVER THE COLDER WATERS. DENSE FOG
WILL PROBABLY FORM TONIGHT ALONG THE LAKESHORE SOUTH OF STURGEON
BAY AND WILL LIKELY EXPAND NORTHWARD TONIGHT AND SUNDAY. THERE MAY
BE SOME DISSIPATION OF THE FOG SUNDAY AFTERNOON WHEN THE WIND
PICKS UP. THERE MAY BE PERIODS OF DENSE FOG THROUGH WEDNESDAY WITH
A POSSIBLE BREAK MONDAY AND MONDAY NIGHT.
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......MPC
MARINE.........RDM
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1249 PM CDT SAT JUN 22 2013
.UPDATE...
ISSUED AT 1248 PM CDT SAT JUN 22 2013
CURRENTLY WATCHING A WARM FRONT ALONG THE MN/IA WARM FRONT FOR
THUNDERSTORM DEVELOPMENT THIS AFTERNOON. RAP PRODUCES
5000-5500J/KG OF 0-1KM ML MUCAPE ALONG THIS WARM FRONT WITH
INCREASING MOISTURE TRANSPORT/HEATING. ALSO...SIGNIFICANT 0-6KM
BULK SHEAR OF 35-40KT DEPICTED ALONG/NORTH OF THE FRONT. THINKING
THAT WITH HEATING AND WARM FRONTAL BOUNDARY MAKING A MOVE
NORTH...CONVECTION WILL FIRE ALONG THE FRONT WITH MOST NUMEROUS
SHRA/TS ACTIVITY FROM KFSD AND ALONG THE MN/IA BORDER...WITH
EASTERN FRINGES OF THIS CONVECTION GETTING INTO NORTHEAST
IA/SOUTHEAST MN LATE IN THE AFTERNOON. OF NOTE IS STRONG 0-1
MLCIN IN PLACE RIGHT NOW. FEEL THIS WILL EVENTUALLY ERODE THOUGH
AS CIRRUS SHIELD FROM THIS MORNING/S STORMS DISSOLVES AND SURFACE
HEATING GETS GOING. GIVEN THE ABOVE SIGNALS...POTENTIAL IS THERE FOR
DISCRETE SUPERCELLS WITH LARGE HAIL/WIND/ISOLATED TORNADO THREAT
MAINLY FOR PORTIONS OF SOUTHEAST MN/NORTHEAST IA.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 349 AM CDT SAT JUN 22 2013
MAIN FORECAST CONCERNS THIS PERIOD...SHRA/TSRA CHANCES...HEAVY RAIN
AND SEVERE THREATS THRU THE PERIOD...TEMPERATURES.
DATA ANALYSIS AT 06Z HAD LOW PRESSURE OVER EASTERN CO WITH A
TROUGH TO THE NORTHEAST INTO THE UPPER MIDWEST. SEVERAL WEAKER WAVES
OF LOW PRESSURE ALONG THIS TROUGH/FRONT INTO WI/MI. TROUGH AND OLD
OUTFLOW BOUNDARIES REMAIN THE FOCUS FOR SHRA/TSRA DEVELOPMENT AGAIN
EARLY THIS MORNING AS THE LOW LEVEL JET AND MOISTURE TRANSPORT PUSH
AN AIRMASS WITH 1.5 TO 2 INCH PW/S NORTH/NORTHEAST INTO IA/MN/WI.
RATHER MASSIVE CONVECTIVE COMPLEX EARLY THIS MORNING FROM SOUTHERN
LK MI TO SOUTHERN MN AND EASTERN NEB...AROUND THE EDGE OF THE
STRONGER MID LEVEL CAPPING. UNDER THE CAPPING...EARLY MORNING TEMPS
IN THE MID 70S TO NEAR 80 ACROSS MUCH OF IA.
22.00Z MODELS LOOK TO HAVE INITIALIZED WELL...THOUGH NOT AS
SIMILARLY AS ONE WOULD LIKE. AS EXPECTED IN A FORECAST DOMINATED BY
MESO-SCALE FORCINGS AND CONVECTION ACROSS THE REGION...SOLUTIONS
OFFERING A VARIETY OF SENSIBLE WEATHER OUTCOMES FOR THE NEXT FEW
DAYS. DPROG/DT OF 500MB HGTS AT 22.00Z SHOWED THE MODEL RUNS OF
20.00Z AND 21.00Z VERIFIED QUITE WELL WITH THE LARGER SCALE FEATURES
OVER NOAM/EASTERN PAC. MOST OF THE EARLIER RUNS WERE A BIT WEAK WITH
SHORTWAVE FEATURES OVER THE CENTRAL CONUS TO GREAT LAKES AND WERE A
BIT HIGH WITH 500MB HGTS OVER THE UPPER MIDWEST. MODELS TRENDING
TOWARD A TIGHTER CONSENSUS TODAY THRU SUN...AT LEAST WITH THE
NORTHERN ROCKIES TROUGH AS IT LIFTS INTO THE NORTHERN PLAINS. TREND
IS A BIT STRONGER WITH TROUGHING AS IT LIFTS ACROSS THE NORTHERN
PLAINS TOWARD NORTHERN MN/WESTERN ONT TONIGHT/SUN. PLENTY OF DETAIL
DIFFERENCES WITH SMALLER SCALE FEATURES THRU THE SOUTHWEST FLOW
ACROSS THE CENTRAL PLAINS INTO UPPER MIDWEST AHEAD OF THE TROUGH.
CHECK OF OBS VS. MODEL DATA AT 06Z SHOWED MODELS TO BE REASONABLE
WITH THE SFC MASS FIELDS OVER THE CENTRAL CONUS...BUT SFC PRESSURE
FIELDS QUITE DISTURBED FROM EASTERN NEB TO WI BY ALL THE ONGOING
CONVECTION. PER WV IMAGERY...ECMWF LOOKS BEST WITH THE CENTRAL CONUS
SHORTWAVE DETAILS. MOST OF THE OTHERS LOOK TO SUFFER SOME FORM OF
CONVECTIVE FEEDBACK WITH COMPACT/STRONG VORTICITY MAXIMA OVER THE
NORTHERN PLAINS/UPPER MIDWEST. ECMWF/GEM/SREF LOOKED BETTER WITH
THE 00-06Z PRECIP OVER THE UPPER MIDWEST...NAM/GFS WERE TOO FAR
SOUTH WITH CONVECTION OVER IA. LOCAL/REGIONAL WRF MODELS CATCHING
ONTO CONVECTIVE EVOLUTION EARLY THIS MORNING. FIRST TO CATCH IT WERE
THE ARX-WRF AND EAST-ARW. GIVEN THE MODEL DIFFERENCES AND THEIR
IMPACTS ON THE SENSIBLE WEATHER THRU THE WEEKEND...SHORT TERM FCST
CONFIDENCE IS BELOW AVERAGE. GENERALLY FAVORED A MODEL/ENSEMBLE
CONSENSUS...WEIGHTED TOWARD THE NON GFS/NAM MODELS.
FAVORING THE SUITE OF LOCAL/REGIONAL HIGH-RES WRF MODELS...CONVECTION
WILL BE ONGOING ACROSS AT LEAST PORTIONS OF THE AREA THIS MORNING AS
THE LOW LEVEL JET/MOISTURE TRANSPORT/THETA-E CONVERGENCE VEERS ACROSS
MN/IA/WI. TRENDED SHRA/TSRA CHANCES TOWARD 70-80 PERCENT ACROSS MUCH
OF THE FCST AREA AT 12Z...THEN TRENDING DOWNWARD THRU THE MORNING.
ONLY CARRIED 20-40 PERCENT SHRA/TSRA CHANCES ACROSS MAINLY THE
NORTHWEST/NORTH PARTS OF THE FCST AREA THIS AFTERNOON...CLOSER TO THE
MAIN TROUGH/FRONTAL BOUNDARY AND THE MID LEVEL WARMING/CAPPING
BUILDING OVER THE SOUTHEAST HALF OF THE FCST AREA. WITH WHAT LOOKS
TO BE A BREAK LATER THIS MORNING/AFTERNOON...WILL NOT EXTEND FLASH
FLOOD WATCH BEYOND ITS CURRENT 17Z END TIME. MOISTURE TRANSPORT
INCREASES INTO THE AREA AGAIN THIS AFTERNOON WITH 2K-3K J/KG OF
CAPE AND SOUNDINGS SHOWING MINIMAL CAPPING...WILL LEAVE A 20-40
PERCENT SHRA/TSRA CHANCE THRU THE AFTERNOON. GIVEN THE /FAT/ CAPES...
STORMS THIS AFTERNOON/EARLY THIS EVENING WOULD POSE A THREAT OF
LARGE HAIL. APPEARS AREA MAY GET MORE OF A BREAK FROM THE WIDESPREAD
CONVECTION TONIGHT/EARLY SUN AS THE MAIN TROUGH/FRONT WITH ITS
CONVERGENCE/LIFT MOVE NORTH OF THE AREA. LEFT SHRA/TSRA CHANCES
TONIGHT MAINLY IN THE 20-40 PERCENT RANGE. DAY CREW WILL HAVE TO RE-
EVALUATE THE HYDRO SITUATION...WATCH TRENDS THRU THE DAY AND SEE
WHICH IF ANY OF THE MODELS ARE MORE CORRECT WITH CONVECTIVE EVOLUTION
THE NEXT 24-36HRS.
BY SUN AFTERNOON THE MAIN MID LEVEL TROUGH LIFTING INTO NORTHWEST MN
PUSHES THE SFC-850MB FRONT/TROUGH BACK TO THE SOUTHEAST. FORCING/
LIFT AHEAD OF THIS FEATURE PUSHING INTO THE AIRMASS OVER THE AREA
WITH SOME 2K-3K J/KG MU CAPE AND PW VALUES OF 1.5 TO 2 INCHES SHOULD
IGNITE ANOTHER ROUND OF SHRA/TSRA WITH HEAVY RAIN AND SEVERE
POTENTIAL. GIVEN THE RECENT RAINS APPEARS ANOTHER FLASH FLOOD WATCH
MAY BE NEEDED SUN AFTERNOON/EVENING.
HIGH TEMPERATURES TODAY/SUN REMAIN TRICKY...BASED ON WHEN CONVECTION
WOULD CLEAR THE AREA AND HOW QUICKLY CLOUDS THIN/CLEAR AND ALLOW
FOR SOME SUNSHINE. GIVEN THE UNCERTAINTIES...STAYED NEAR THE MODEL/
ENSEMBLE CONSENSUS FOR HIGHS/LOWS TODAY THRU SUN.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 349 AM CDT SAT JUN 22 2013
MODEL CONSENSUS CONTINUES TO IMPROVE FOR SUN NIGHT THRU MON NIGHT AS
THE MID LEVEL TROUGH LIFTS INTO ONT AND HGTS RISE OVER THE REGION.
HOWEVER THE LOWER LEVEL PATTERN REMAINS ACTIVE/UNSETTLED...WITH
PLENTY OF MODEL DETAIL DIFFERENCES. FCST CONFIDENCE IN THIS PERIOD
REMAINS BELOW AVERAGE. THE PASSING MID LEVEL TROUGH PUSHES THE WEAK
SFC TROUGH/FRONT INTO ACROSS THE AREA SUN NIGHT. SHRA/TSRA CHANCES IN
THE 50-70 PERCENT RANGE SUN NIGHT LOOK REASONABLE. GIVEN THE
FORCING...STRONG INSTABILITY AND INCREASED WINDS/SHEAR ALOFT...TSRA
SUN NIGHT COULD BE SEVERE WITH THREATS OF WINDS AND HAIL. THE
TROUGH/FRONT FROM SUN/AFTERNOON/EVENING LIFTS BACK NORTH ALREADY ON
ON MON...PROVIDING FOCUS FOR CONVERGENCE/LIFT AND SHRA/TSRA
FORMATION...THIS AS MODELS SHOW POTENTIAL FOR ONE OR MORE SHORTWAVES
TO BE RIPPLING THRU THE FLOW AND ACROSS THE REGION. CONTINUED 20-40
PERCENT SHRA/TSRA CHANCES MON. LOW LEVEL JET/MOISTURE TRANSPORT/
THETA-E CONVERGENCE INCREASE INTO THE AREA MON NIGHT AS THIS BOUNDARY
LIFTS NORTH ACROSS THE AREA. CARRIED 30-50 PERCENT SHRA/TSRA CHANCES
MON NIGHT.
GIVEN THE LOWER CONFIDENCE ON THE CONVECTIVE DETAILS...USED A
MODEL/ENSEMBLE CONSENSUS FOR LOWS/HIGHS SUN NIGHT THRU MON NIGHT.
WITH ALL THE SHORT TERM CONCERNS AND UNCERTAINTIES...NOT MUCH TIME
SPENT LOOKING AT THE DAY 4-7 PERIOD. MEDIUM RANGE MODEL RUNS OF
22.00Z DO OFFER SOME CONSENSUS FOR A FLAT WEST TO SOUTHWEST FLOW
ALOFT OVER THE CENTRAL CONUS TUE/WED...WITH SHORTWAVES TO BE
RIPPLING THRU THIS FLOW AND ACROSS THE REGION. LONGER TERM FCST
CONFIDENCE AVERAGE. WITH THE MOIST/UNSTABLE AIRMASS IN PLACE AND ONE
OR MORE BOUNDARIES FLOATING AROUND THE REGION...SHRA/TSRA CHANCES
LOOK TO CONTINUE TUE THRU AT LEAST WED NIGHT. BY THU MODELS POINT TO
RIDGING BUILDING OVER THE WESTERN CONUS AND THE FLOW ALOFT OVER THE
UPPER MIDWEST BECOMING NORTHWEST FOR THU/FRI. THIS NORTHWEST FLOW
WOULD DRIVE SOME DRIER/COOLER AIR FROM SOUTH CENTRAL CAN/NORTHERN
PLAINS...AND DECREASING SHRA/TSRA CHANCES...INTO THE AREA FOR THE
LATER PARTS OF THE WEEK. MODEL/ENSEMBLE CONSENSUS HIGHS/LOWS FOR
TUE THRU FRI LOOK WELL TRENDED FOR NOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1248 PM CDT SAT JUN 22 2013
EXPECTING SCATTERED THUNDERSTORMS TO FIRE THIS AFTERNOON ALONG A
WARM FRONT SITUATED ALONG THE IA/MN BORDER. PLAN ON THE BULK OF THIS
THUNDERSTORM ACTIVITY TO EXTEND FROM KFSD THROUGH SOUTH-CENTRAL
MN...WITH EASTERN FRINGES OF THIS CONVECTION REACHING TOWARD THE
MISSISSIPPI RIVER INCLUDING KRST/KLSE TAF SITES. THE WARM FRONT IS
EXPECTED TO PUSH NORTH OF THE AREA AFTER MIDNIGHT...TAKING THE
THUNDERSTORM ACTIVITY WITH IT. BOTTOM LINE...INCLUDED VCTS BKN030-035CB
IN THE KRST/KLSE TAFS FROM 21Z THROUGH 06Z. OTHER THAN SOME 6SM
BR IN THE 08-13Z TIME FRAME...EXPECTING VFR CONDITIONS THEN TO
PREVAIL THROUGH 18Z SUNDAY. SHRA/TS LOOKING LIKELY AGAIN SUNDAY
AFTERNOON/EVENING AS A COLD FRONT PUSHES EAST OUT OF THE NORTHERN
PLAINS TOWARD THE AREA.
&&
.HYDROLOGY...TONIGHT INTO SATURDAY
ISSUED AT 349 AM CDT SAT JUN 22 2013
A FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH NOON TODAY. CONVECTION
SHOULD BE WANING/ENDING THRU THE MORNING...WITH PLENTY OF
UNCERTAINTY CONCERNING REDEVELOPMENT AND EVOLUTION THIS AFTERNOON
AND EVENING. HEAVY RAINS FROM FRI EVENING/EARLY THIS MORNING WERE
NOT AS WIDESPREAD AS THE NIGHT BEFORE. CONVECTION THIS AFTERNOON/
EVENING APPEARS AS THOUGH IT MAY BE MORE SCATTERED AND PROGRESSIVE
THUS WILL NOT BE EXTENDING THE FLASH FLOOD WATCH AT THIS TIME.
MAIN FORCING/LIFT LOOK TO LIFT NORTH OF THE FCST AREA FOR TONIGHT/
SUN MORNING...BUT STRONGER FORCING /IN THE FORM OF A PASSING MID
LEVEL TROUGH AND APPROACHING SFC-850MB TROUGH/FRONT/ MOVES BACK
INTO THE AREA SUN AFTERNOON/EVENING. MORE WIDESPREAD CONVECTION...
CAPABLE OF PRODUCING HEAVY RAINS...LOOKS LIKELY AS THESE FEATURES
PASS. APPEARS A FLASH FLOOD WATCH MAY BE NEEDED AGAIN SUN
AFTERNOON INTO SUN NIGHT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...DAS
SHORT TERM...RRS
LONG TERM....RRS
AVIATION...DAS
HYDROLOGY....RRS
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1237 PM CDT SAT JUN 22 2013
UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND SUNDAY
ISSUED AT 442 AM CDT SAT JUN 22 2013
CONTINUE WITH ISSUES ON WHERE AND WHEN CONVECTION WILL AFFECT
AREA. WATER VAPOR IMAGERY SHOWING NUMBER OF DISTURBANCES MOVING
THROUGH SOUTHWEST FLOW ALOFT OVER UPPER MIDWEST. CONVECTION
ASSOCIATED WITH THESE DISTURBANCES CURRENTLY EXTENDS OVER SOUTHERN
WI THROUGH MN AND NEBRASKA. MAIN ISSUES TONIGHT WITH THE
CONVECTION...HEAVY RAIN. IR IMAGERY SHOWING WARMING TOPS ATTM WITH
DOWNWARD TREND EXPECTED TO CONTINUE INTO THE MORNING HOURS. OVER
NORTHEAST WI...STABLE AIR FILTERED SOUTH BEHIND BOUNDARY DROPPING
SOUTH OUT OF LAKE SUPERIOR DURING THE EVENING. MODEL OF CHOICE
QUESTIONABLE...WHILE GFS AND TO SOME EXTENT EC APPEARED TO BE
DOING WELL AT 6Z WITH CONVECTIVE TRENDS...THEY QUICKLY LOSE
REALITY AS MOVE INTO THIS MORNING. HAVE TRENDED TOWARDS CURRENT
RADAR TRENDS AND HRRR WHICH BRINGS WAINING CONVECTION NORTH INTO
CENTRAL AND NORTH CENTRAL WI THIS MORNING. THUS WILL GO HIGH
CHANCE OR LIKELY OVER THESE LOCATIONS FOR FIRST PART OF DAY.
REMAINDER OF AREA...LOWER CHANCE POPS THROUGH THE DAY. HRRR
SUGGEST LIMITED PCPN THROUGH AFTERNOON. THIS MAKES SENSE AS BEST
FORCING/ ISENTROPIC LIFT WEST OVER SOUTHERN MN THIS
AFTERNOON...EVENING. MODELS CONTINUE TO TRY AND BRING WARM FRONT
NORTH THROUGH THE AREA TONIGHT. WITH UNCERTAINTY...WILL STICK TO
CHANCE POPS THROUGH SUN. COLD FRONT APPROACHES STATE LATE IN DAY
SUN AS MAIN UPPER WAVE LIFTS NORTHEAST THROUGH HIGH PLAINS.
TRENDED POPS HIGHER WEST GIVEN PROXIMITY OF FRONT.
AGAIN OVERNIGHT STORMS PRODUCED SIG PCPN AS HAVE PLENTY OF
MOISTURE TO WORK WITH WITH PW`S IN 1.5 TO 2.0 INCH RANGE. THIS TO
CONTINUE INTO SUNDAY. PLENTY OF INSTABILITY AROUND THROUGH THE
PERIOD...THOUGH SHEAR IS LIMITED AT LEAST UNTIL SUN...WHEN MODELS
SUGGEST INCREASES TO NR 40 KTS. WILL CONTINUE TO HIGHLIGHT HEAVY
RAIN POTENTIAL AS MAIN ISSUE...WITH STRONG DAMAGING WIND THREAT
POSSIBLE TODAY AND TONIGHT.
GIVEN LOW CLOUDS/CLOUDS EXPECTED FOR FIRST HALF OF DAY AND
EASTERLY COMPONENT OF WIND...HAVE DROPPED HIGHS A GOOD 5 DEGS
TODAY. HAVE NOT MADE ANY SIG CHANGE TO SUN ATTM DUE TO UNCERTAINTY
ON CONVECTION.
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY
ISSUED AT 442 AM CDT SAT JUN 22 2013
UPPER RIDGE WILL GRADUALLY RETROGRADE WESTWARD INTO THE WESTERN
UNITED STATES. THIS WILL EVENTUALLY CHANGE THE SOUTHWEST FLOW
PATTERN TO A NORTHWEST FLOW PATTERN...BRINGING COOLER TEMPERATURES
AND LOWER HUMIDITY BY THE END OF THE WEEK.
CONSIDERING MODELS ARE HAVING TOUGH TIME OVER THE LAST FEW DAYS
IN THE PLACEMENT OF CONVECTION AND LOCALLY HEAVY RAIN...LOWER
THAN NORMAL CONFIDENCE IN THE DETAILS OF THE FORECAST AS THE MODELS
CONTINUE TO SHOW SEVERAL COMPLEXES MOVING ACROSS THE WESTERN GREAT
LAKES EARLY TO MIDDLE OF NEXT WEEK. THEREFORE...WILL CONTINUE CHANCES
OF SHOWERS AND THUNDERSTORMS EACH DAY THROUGHOUT THE PERIOD. SOME
INDICATIONS BY THE MODELS THAT MONDAY COULD END UP BEING DRIER THAN
ADVERTISED...BUT WILL BELIEVE IT WHEN I SEE IT.
STILL THE POTENTIAL FOR SEVERE WEATHER AND LOCALLY HEAVY EARLY TO
MIDDLE PORTIONS OF NEXT WEEK. HAZARDOUS WEATHER OUTLOOK HAS THIS
MENTIONED ALONG WITH THE UNCERTAINTY IN TIMING. ONLY MINOR CHANGES
MADE TO THE EXTENDED FORECAST ON A FEW DAYS...MORE COORDINATION
PURPOSES.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1236 PM CDT SAT JUN 22 2013
CONFIDENCE HAS NOT IMPROVED ANY IN THE FORECAST DETAILS OVER THE
NEXT 24 HOURS. PARTIAL CLEARING OCCURRING IN THE VICINITY OF
VARIOUS SHORTWAVE TROUGHS OVER MINNESOTA AND WESTERN WISCONSIN SUGGESTS
POTENTIAL FOR STORMS WILL INCREASE LATER THIS AFTERNOON IF THESE
TRENDS CONTINUE. IF STORMS DEVELOP...WOULD LIKELY IMPACT CENTRAL
AND NORTH-CENTRAL WISCONSIN. NOCTURNAL STORMS COULD ALSO REFIRE
ALONG A WARM FRONT AS IT LIFTS NORTH OVER MINNESOTA AND WISCONSIN
TONIGHT. IF THIS OCCURS...STORMS WOULD TRACK ALONG THE WARM FRONT
EAST-SOUTHEAST INTO NORTH-CENTRAL WISCONSIN AND POSSIBLY NORTHEAST
WISCONSIN LATE. UNCERTAINTIES REVOLVING AROUND LOCATION AND TIMING
OF STORMS IS TOO HIGH TO INCLUDE TSRA IN TAFS AT THIS TIME.
OTHERWISE...CIGS IMPROVING THIS AFTERNOON TO VFR.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....TE
LONG TERM......ECKBERG
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1020 AM CDT SAT JUN 22 2013
.UPDATE...
N-S CONVECTIVE BAND OVER SOUTHERN WI WILL CONTINUE TO MOVE EAST TO
OVER LAKE MICHIGAN BY EARLY AFTERNOON. HAVE UPDATED THE FORECAST TO
REFLECT THIS AND INCREASED CHANCES OF RAIN TO CATEGORICAL. HAVE
KNOCKED MAX TEMPS DOWN A FEW DEGREES SINCE USUAL DAYTIME HEATING
WILL NOT BE THERE. IN FACT...WE WILL PROBABLY KNOCK THEM BACK IN
MORE SINCE IT`LL BE MOSTLY CLOUDY WITH CONVECTIVE CLOUD CANOPY
OVERHEAD. YESTERDAY WE NEVER RECOVERED PAST 80.
THE AFTERNOON HOURS SHOULD BE QUIET AFTER THE CONVECTIVE BAND
EXITS....LIKE YESTERDAY. FORECAST MODELS..BOTH THE LARGE SCALE AND
MESO TYPES HAVE VARIOUS SOLUTIONS FOR THUNDERSTORM POSSIBILITIES
THIS AFTERNOON AND TONIGHT. GIVEN THAT LOW LEVEL BOUNDARY HAS BEEN
SHOVED BACK SOUTH INTO NORTHERN ILLINOIS MAKES IT DIFFICULT TO GET
REGENERATION OF STORMS OVER SOUTHERN WI UNTIL LATE IN THE
AFTERNOON. HRRR MODELS HINTS AT THIS.
.AVIATION/18Z TAFS/...
JUST PRIOR TO 18Z THERE WERE POCKETS OF IFR CIGS ALONG OR NEAR THE
LAKE MICHIGAN SHORELINE FROM MILWAUKEE TO KENOSHA. EXPECT THESE
CONDITIONS TO BE REINFORCED BY CONVECTIVE RAIN BAND WHICH WILL MOVE
FROM SOUTHCENTRAL INTO SOUTHEAST WISCONSIN AND THEN OVER LAKE
MICHIGAN. OTHERWISE...VFR CONDS WITH MULTIPLE LAYERS OF CLOUDS.
BRIEF MVFR VSBY CONDITIONS WITH THE HEAVIER SHOWERS/RAIN. CIGS AND
VISIBILITIES SHOULD BE UP AND DOWN SATURDAY NIGHT WITH ADDITIONAL
CHANCES OF SHOWERS AND STORMS. HOWEVER...GENERALLY VFR CONDS
EXPECTED.
.PREV DISCUSSION...ISSUED 238 AM CDT SAT JUN 21 2013
.SHORT TERM...TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM.
THE 250 MB UPPER RIDGE EXTENDS FROM THE SOUTHEAST U.S. INTO THE LAKE
MICHIGAN AREA...WITH A SHORTWAVE OVER THE NORTHERN ROCKIES. AT 500
MB A MODERATE SOUTHWEST FLOW WILL PERSIST ACROSS THE NORTHERN
PLAINS TO NORTHWEST WISCONSIN.
ACTIVE THUNDERSTORM FORECAST FOR THIS PERIOD ACROSS THE AREA. SHORT
TERM MODELS INDICATE THE SURFACE WARM FRONT WILL BE NEAR THE
FORECAST AREA AND TENT TO SHIFT NORTHWARD TONIGHT. 850MB THERMAL
RIDGE WILL REMAIN POINTED INTO THE REGION TODAY AND TONIGHT.
THE NOSE OF THE 850MB LOW LEVEL JET IS ACROSS SOUTHERN WISCONSIN
EARLY THIS MORNING...THEN PUSHES EAST TOWARDS THE EASTERN GREAT
LAKES WHILE THE MAIN JET ACROSS THE CENTRAL PLAINS INTO IOWA TODAY
WITH A 30 KNOT FLOW ACROSS SOUTHERN WISCONSIN AGAIN TONIGHT.
PRECIPITABLE WATER VALUES REMAIN HIGH AROUND 1.5 TO 2 INCHES.
NONE OF THE MESO MODELS ARE DOING A VERY GOOD JOB WITH THE
THUNDERSTORMS. IT APPEARS A WEST TO EAST LINE OF THUNDERSTORMS
EXTENDS FROM THE IOWA MINNESOTA BORDER TO SOUTHERN LAKE MICHIGAN
JUST NORTH OF THE 850 MOISTURE TRANSPORT VECTORS. THE EAST PART OF
THIS LINE WAS SAGGING SOUTH...BUT WEST OF MADISON THERE IS A SLOW
NORTH PUSH.
THIS WOULD SUPPORT A LARGE MCC WHICH SHOULD AFFECT THE FORECAST AREA
THIS MORNING. THEN MORE STORMS COULD FORM THIS AFTERNOON AND
TONIGHT. HEAVY RAINFALL IS EXPECTED AND A FLASH FLOOD WATCH MAY BE
NEEDED. HOWEVER THE CURRENT SHORT TERM MESO MODELS WOULD NOT
INDICATE ENOUGH RAINFALL FOR THIS.
TEMPERATURES ARE GOING TO BE TOUGH AS WELL...DEPENDING ON CONVECTION
TRENDS AND CLOUDS. M ID 80S MOST LIKELY GIVEN THE EXPECTED CLOUD
DEBRIS. HOWEVER WITH THE HIGH DEW POINTS IT WILL BE HUMID.
.SUNDAY THROUGH MONDAY NIGHT...FORECAST CONFIDENCE MEDIUM.
MAIN CONCERNS ARE WX/POPS AND HIGH TEMPERATURES. SUNDAYS WEATHER
ARE TIED TO WHETHER OR NOT A MESOSCALE LIFTING MECHANISM WILL BE
PRESENT AND CAP CAN HOLD. OTHERWISE THE OTHER INGREDIENTS FOR DEEP
MOIST CONVECTION WILL BE PRESENT - A MODERATELY UNSTABLE ENVIRONMENT
WITH AT LEAST 1500-2000 J/KG MEAN LAYER CAPE AND AMPLE LOW-LEVEL
MOISTURE WITH SURFACE DEW POINTS AROUND 70. THOUGH STORM MODE AND
ORGANIZATION WILL BE A LIMITING FACTOR IN ALL OF THIS GIVEN THE LOW
VALUES OF DEEP LAYER 0-6 KM SHEAR. DRY CONDITIONS MAY BE SEEN IF
THE CAP HOLDS AND SUNDAY LACKS A LIFTING MECHANISM. KEPT A SLIGHT
CHANCE/CHANCE GIVEN THE UNCERTAINTY.
THE BETTER CHANCE FOR PRECIP EXISTS SUNDAY NIGHT INTO MONDAY.
WHEREIN...NUMERICAL MODELS ARE IN A GENERAL AGREEMENT OF A SHORT
WAVE TROUGH AND AN ASSOCIATED VORT MAX MOVING THROUGH THE AREA
OVERNIGHT/EARLY MONDAY. PRECIP CHANCES CONTINUE MONDAY AS PRECIP
FROM THE MORNING COULD LINGER AND GIVEN THE SUPPORT OF SYNOPTIC
LIFT...SEEN WITH LOW-LEVEL Q-VECTOR DIVG IN PLACE AND LIGHT LOW-
LEVEL WAA OCCURRING.
THE MODEL CONSENSUS FOR 925 HPA TEMPS SUNDAY ARE AROUND 24-26 C THAT
CORRESPOND TO 87-91 F PROVIDED INSOLATION/MIXING IS SUFFICIENT. ANY
CONVECTIVE DEBRIS THOUGH WOULD IMPACT THIS. RH FIELDS AND WHAT IS
EXPECTED REGARDING WX/POPS GIVE CONFIDENCE TO LEAN TOWARDS THE
HIGHER GUIDANCE WITH HIGHS IN THE UPPER 80S-AROUND 90 FORECAST.
HEAT INDICES ARE EXPECTED TO BE GENERALLY IN THE MID TO UPPER 90S
SUNDAY.
.LONG TERM...TUESDAY THROUGH FRIDAY NIGHT...FORECAST CONFIDENCE
MEDIUM.
SHIFT IN THE PATTERN STILL EXPECTED THIS WEEK WITH A MORE ZONAL 500
HPA PATTERN DEVELOPING MONDAY-TUESDAY ASSOCIATED WITH HT RISES IN
THE NORTHERN ROCKIES AND GREAT PLAINS SUNDAY-EARLY MONDAY. CHANCES
FOR PRECIP WILL CONTINUE INTO THE NEW WORK WEEK AS SHORT WAVES
TROUGHS TRAVERSE THE REGION WITH THE BEST CHANCES TUESDAY
AFTERNOON INTO WEDNESDAY. HIGHS ABOVE NORMAL UNTIL FRIDAY WHEN
PATTERN BREAKS DOWN AS A LONG WAVE TROUGH DEVELOPS OVER THE GREAT
LAKES REGION. NORTHWEST FLOW WILL USHER COOLER AIR FRIDAY AND
SATURDAY WITH HIGHS MOVING TOWARDS BELOW/NEAR NORMAL SEASONAL
VALUES.
&&
.AVIATION/12Z TAFS/...
A BAND OF THUNDERSTORMS WILL EXTEND ACROSS SOUTHERN WISCONSIN
DURING THE EARLY MORNING HOURS. MVFR/IFR IN STORMS...WITH VFR TO
THE NORTH OF THE BAND. SOME MVFR CLOUDS THIS MORNING...THEN MAINLY
VFR. THE CHANCE OF THUNDERSTORMS WILL CONTINUE THIS AFTERNOON AND
TONIGHT WITH A WARM FRONT ACROSS/NEAR SOUTHERN WISCONSIN.
&&
.MARINE...
DEW POINTS RISING THROUGH THE 60S WILL OVERSPREAD THE COOL LAKE
WATERS TODAY AND TONIGHT. SOME FOG FORMATION IS POSSIBLE...AND MAY
LINGER ON AND OFF THROUGH THE WEEKEND.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...SH
SUNDAY THROUGH FRIDAY...ET
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
653 AM CDT SAT JUN 22 2013
UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND SUNDAY
ISSUED AT 442 AM CDT SAT JUN 22 2013
CONTINUE WITH ISSUES ON WHERE AND WHEN CONVECTION WILL AFFECT
AREA. WATER VAPOR IMAGERY SHOWING NUMBER OF DISTURBANCES MOVING
THROUGH SOUTHWEST FLOW ALOFT OVER UPPER MIDWEST. CONVECTION
ASSOCIATED WITH THESE DISTURBANCES CURRENTLY EXTENDS OVER SOUTHERN
WI THROUGH MN AND NEBRASKA. MAIN ISSUES TONIGHT WITH THE
CONVECTION...HEAVY RAIN. IR IMAGERY SHOWING WARMING TOPS ATTM WITH
DOWNWARD TREND EXPECTED TO CONTINUE INTO THE MORNING HOURS. OVER
NORTHEAST WI...STABLE AIR FILTERED SOUTH BEHIND BOUNDARY DROPPING
SOUTH OUT OF LAKE SUPERIOR DURING THE EVENING. MODEL OF CHOICE
QUESTIONABLE...WHILE GFS AND TO SOME EXTENT EC APPEARED TO BE
DOING WELL AT 6Z WITH CONVECTIVE TRENDS...THEY QUICKLY LOSE
REALITY AS MOVE INTO THIS MORNING. HAVE TRENDED TOWARDS CURRENT
RADAR TRENDS AND HRRR WHICH BRINGS WAINING CONVECTION NORTH INTO
CENTRAL AND NORTH CENTRAL WI THIS MORNING. THUS WILL GO HIGH
CHANCE OR LIKELY OVER THESE LOCATIONS FOR FIRST PART OF DAY.
REMAINDER OF AREA...LOWER CHANCE POPS THROUGH THE DAY. HRRR
SUGGEST LIMITED PCPN THROUGH AFTERNOON. THIS MAKES SENSE AS BEST
FORCING/ ISENTROPIC LIFT WEST OVER SOUTHERN MN THIS
AFTERNOON...EVENING. MODELS CONTINUE TO TRY AND BRING WARM FRONT
NORTH THROUGH THE AREA TONIGHT. WITH UNCERTAINTY...WILL STICK TO
CHANCE POPS THROUGH SUN. COLD FRONT APPROACHES STATE LATE IN DAY
SUN AS MAIN UPPER WAVE LIFTS NORTHEAST THROUGH HIGH PLAINS.
TRENDED POPS HIGHER WEST GIVEN PROXIMITY OF FRONT.
AGAIN OVERNIGHT STORMS PRODUCED SIG PCPN AS HAVE PLENTY OF
MOISTURE TO WORK WITH WITH PW`S IN 1.5 TO 2.0 INCH RANGE. THIS TO
CONTINUE INTO SUNDAY. PLENTY OF INSTABILITY AROUND THROUGH THE
PERIOD...THOUGH SHEAR IS LIMITED AT LEAST UNTIL SUN...WHEN MODELS
SUGGEST INCREASES TO NR 40 KTS. WILL CONTINUE TO HIGHLIGHT HEAVY
RAIN POTENTIAL AS MAIN ISSUE...WITH STRONG DAMAGING WIND THREAT
POSSIBLE TODAY AND TONIGHT.
GIVEN LOW CLOUDS/CLOUDS EXPECTED FOR FIRST HALF OF DAY AND
EASTERLY COMPONENT OF WIND...HAVE DROPPED HIGHS A GOOD 5 DEGS
TODAY. HAVE NOT MADE ANY SIG CHANGE TO SUN ATTM DUE TO UNCERTAINTY
ON CONVECTION.
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY
ISSUED AT 442 AM CDT SAT JUN 22 2013
UPPER RIDGE WILL GRADUALLY RETROGRADE WESTWARD INTO THE WESTERN
UNITED STATES. THIS WILL EVENTUALLY CHANGE THE SOUTHWEST FLOW
PATTERN TO A NORTHWEST FLOW PATTERN...BRINGING COOLER TEMPERATURES
AND LOWER HUMIDITY BY THE END OF THE WEEK.
CONSIDERING MODELS ARE HAVING TOUGH TIME OVER THE LAST FEW DAYS
IN THE PLACEMENT OF CONVECTION AND LOCALLY HEAVY RAIN...LOWER
THAN NORMAL CONFIDENCE IN THE DETAILS OF THE FORECAST AS THE MODELS
CONTINUE TO SHOW SEVERAL COMPLEXES MOVING ACROSS THE WESTERN GREAT
LAKES EARLY TO MIDDLE OF NEXT WEEK. THEREFORE...WILL CONTINUE CHANCES
OF SHOWERS AND THUNDERSTORMS EACH DAY THROUGHOUT THE PERIOD. SOME
INDICATIONS BY THE MODELS THAT MONDAY COULD END UP BEING DRIER THAN
ADVERTISED...BUT WILL BELIEVE IT WHEN I SEE IT.
STILL THE POTENTIAL FOR SEVERE WEATHER AND LOCALLY HEAVY EARLY TO
MIDDLE PORTIONS OF NEXT WEEK. HAZARDOUS WEATHER OUTLOOK HAS THIS
MENTIONED ALONG WITH THE UNCERTAINTY IN TIMING. ONLY MINOR CHANGES
MADE TO THE EXTENDED FORECAST ON A FEW DAYS...MORE COORDINATION
PURPOSES.
&&
.AVIATION...FOR 12Z TAF ISSUANCE
ISSUED AT 638 AM CDT SAT JUN 22 2013
LOW CIGS OVER FAR NORTH ASSOCIATED WITH STABLE NORTHEAST FLOW OFF
LAKE SUPERIOR AND ABUNDANT LOW LEVEL MOISTURE WILL LIFT THIS
MORNING AS DECAYING AREA OF CONVECTION MOVES INTO THE REGION.
MORNING SHOWERS AND THUNDERSTORMS EXPECTED TO CONTINUE TO WANE WITH
QUIET MID DAY PERIOD EXPECTED. SHOWER AND TSTM REDEVELOPMENT
POSSIBLE LATER THIS AFTERNOON ESPECIALLY NORTHWEST PORTION OF WI
AS NEXT UPPER DISTURBANCE MOVES THROUGH. STRONG INSTABILITY IS
EXPECTED...SO STRONG/SEVERE TSTMS WITH TORRENTIAL RAINFALL ARE
POSSIBLE.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....TE
LONG TERM......ECKBERG
AVIATION.......TE
FORECAST DISCUSSION FOR ROUTINE MORNING FORECAST ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND SUNDAY
ISSUED AT 442 AM CDT SAT JUN 22 2013
CONTINUE WITH ISSUES ON WHERE AND WHEN CONVECTION WILL AFFECT
AREA. WATER VAPOR IMAGERY SHOWING NUMBER OF DISTURBANCES MOVING
THROUGH SOUTHWEST FLOW ALOFT OVER UPPER MIDWEST. CONVECTION
ASSOCIATED WITH THESE DISTURBANCES CURRENTLY EXTENDS OVER SOUTHERN
WI THROUGH MN AND NEBRASKA. MAIN ISSUES TONIGHT WITH THE
CONVECTION...HEAVY RAIN. IR IMAGERY SHOWING WARMING TOPS ATTM WITH
DOWNWARD TREND EXPECTED TO CONTINUE INTO THE MORNING HOURS. OVER
NORTHEAST WI...STABLE AIR FILTERED SOUTH BEHIND BOUNDARY DROPPING
SOUTH OUT OF LAKE SUPERIOR DURING THE EVENING. MODEL OF CHOICE
QUESTIONABLE...WHILE GFS AND TO SOME EXTENT EC APPEARED TO BE
DOING WELL AT 6Z WITH CONVECTIVE TRENDS...THEY QUICKLY LOSE
REALITY AS MOVE INTO THIS MORNING. HAVE TRENDED TOWARDS CURRENT
RADAR TRENDS AND HRRR WHICH BRINGS WAINING CONVECTION NORTH INTO
CENTRAL AND NORTH CENTRAL WI THIS MORNING. THUS WILL GO HIGH
CHANCE OR LIKELY OVER THESE LOCATIONS FOR FIRST PART OF DAY.
REMAINDER OF AREA...LOWER CHANCE POPS THROUGH THE DAY. HRRR
SUGGEST LIMITED PCPN THROUGH AFTERNOON. THIS MAKES SENSE AS BEST
FORCING/ ISENTROPIC LIFT WEST OVER SOUTHERN MN THIS
AFTERNOON...EVENING. MODELS CONTINUE TO TRY AND BRING WARM FRONT
NORTH THROUGH THE AREA TONIGHT. WITH UNCERTAINTY...WILL STICK TO
CHANCE POPS THROUGH SUN. COLD FRONT APPROACHES STATE LATE IN DAY
SUN AS MAIN UPPER WAVE LIFTS NORTHEAST THROUGH HIGH PLAINS.
TRENDED POPS HIGHER WEST GIVEN PROXIMITY OF FRONT.
AGAIN OVERNIGHT STORMS PRODUCED SIG PCPN AS HAVE PLENTY OF
MOISTURE TO WORK WITH WITH PW`S IN 1.5 TO 2.0 INCH RANGE. THIS TO
CONTINUE INTO SUNDAY. PLENTY OF INSTABILITY AROUND THROUGH THE
PERIOD...THOUGH SHEAR IS LIMITED AT LEAST UNTIL SUN...WHEN MODELS
SUGGEST INCREASES TO NR 40 KTS. WILL CONTINUE TO HIGHLIGHT HEAVY
RAIN POTENTIAL AS MAIN ISSUE...WITH STRONG DAMAGING WIND THREAT
POSSIBLE TODAY AND TONIGHT.
GIVEN LOW CLOUDS/CLOUDS EXPECTED FOR FIRST HALF OF DAY AND
EASTERLY COMPONENT OF WIND...HAVE DROPPED HIGHS A GOOD 5 DEGS
TODAY. HAVE NOT MADE ANY SIG CHANGE TO SUN ATTM DUE TO UNCERTAINTY
ON CONVECTION.
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY
ISSUED AT 442 AM CDT SAT JUN 22 2013
UPPER RIDGE WILL GRADUALLY RETROGRADE WESTWARD INTO THE WESTERN
UNITED STATES. THIS WILL EVENTUALLY CHANGE THE SOUTHWEST FLOW
PATTERN TO A NORTHWEST FLOW PATTERN...BRINGING COOLER TEMPERATURES
AND LOWER HUMIDITY BY THE END OF THE WEEK.
CONSIDERING MODELS ARE HAVING TOUGH TIME OVER THE LAST FEW DAYS
IN THE PLACEMENT OF CONVECTION AND LOCALLY HEAVY RAIN...LOWER
THAN NORMAL CONFIDENCE IN THE DETAILS OF THE FORECAST AS THE MODELS
CONTINUE TO SHOW SEVERAL COMPLEXES MOVING ACROSS THE WESTERN GREAT
LAKES EARLY TO MIDDLE OF NEXT WEEK. THEREFORE...WILL CONTINUE CHANCES
OF SHOWERS AND THUNDERSTORMS EACH DAY THROUGHOUT THE PERIOD. SOME
INDICATIONS BY THE MODELS THAT MONDAY COULD END UP BEING DRIER THAN
ADVERTISED...BUT WILL BELIEVE IT WHEN I SEE IT.
STILL THE POTENTIAL FOR SEVERE WEATHER AND LOCALLY HEAVY EARLY TO
MIDDLE PORTIONS OF NEXT WEEK. HAZARDOUS WEATHER OUTLOOK HAS THIS
MENTIONED ALONG WITH THE UNCERTAINTY IN TIMING. ONLY MINOR CHANGES
MADE TO THE EXTENDED FORECAST ON A FEW DAYS...MORE COORDINATION
PURPOSES.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1048 PM CDT FRI JUN 21 2013
INITIAL CLUSTER OF TSTMS HAS WEKENED AS IT MOVED TOWARD CENTRAL
WI LATE THIS EVENING. ALTHOUGH THE FIRST ROUND OF STORMS SHOULD MISS
THE TAF SITES...THERE SHOULD STILL BE A CHANCE OF STORMS ACROSS
MUCH OF C/EC WI OVERNIGHT. MVFR CONDITIONS MAY ACCOMPANY THE TSTMS.
LOW CLOUDS WILL BE FOUND ACROSS NORTHERN WI OVERNIGHT...AND MAY
ALSO BE OCCUR ACROSS C/EC WI LATE TONIGHT INTO EARLY SAT. IMPROVING
CONDITIONS ARE EXPECTED BY MID TO LATE SAT MORNING...WITH SCT TSTMS
REDEVELOPING DURING THE LATE AFTERNOON/EARLY EVENING. STRONG INSTABILITY
IS EXPECTED...SO STRONG/SEVERE TSTMS WITH TORRENTIAL RAINFALL ARE
POSSIBLE.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....TE
LONG TERM......ECKBERG
AVIATION.......KIECKBUSCH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1213 AM CDT SAT JUN 22 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 355 PM CDT FRI JUN 21 2013
AT 3 PM...A THUNDERSTORM COMPLEX WAS LOCATED OVER EASTERN SOUTH
DAKOTA. THE HRRR SEEMS TO BE HANDLING THIS SYSTEM THE BEST THIS
AFTERNOON. IT SHOWS THAT THIS SYSTEM WILL MOVE NORTHEAST INTO
NORTHEAST SOUTH DAKOTA AND WEST CENTRAL MINNESOTA LATE THIS
AFTERNOON AND EARLY EVENING. THIS SYSTEM IS INITIALLY FOLLOWING THE
SHORT WAVE TROUGH. HOWEVER AS THE LOW LEVEL JET STRENGTHENS THIS
EVENING AND STRONG 850 MB MOISTURE TRANSPORT WILL MOVE INTO THE
FORECAST AREA. EXPECT SOME DEVELOPMENT ALONG THE ADVANCING WARM
FRONT ON THE SOUTH OF THIS PERIPHERY OF THIS SYSTEM. MLCAPES ALONG
THIS BOUNDARY CLIMB TO AROUND 5000 J/KG LATE THIS AFTERNOON AND
THEN CONTINUES INTO THE EARLY EVENING. WHILE THE 0-6 KM SHEAR IS
NOT FAVORABLE FOR SUPERCELLS...THE 0-3 KM BULK SHEAR IS OVER
40 KNOTS AND IT WILL BE FAVORABLE FOR DAMAGING WINDS. IN ADDITION
WITH DCAPES OVER 1500 J/KG...THIS WOULD ALSO MAKE IT FAVORABLE FOR
THE STORMS TO PRODUCE DAMAGING WINDS. CURRENTLY EXPECTING THE
CURRENT CONVECTION TO EVOLVE INTO 1 OR MORE BOW ECHOS AS THEY
BECOME MORE COLD POOL DOMINANT...AND THESE LINES WOULD LIKELY MOVE
ALONG OR NORTH OF THE INTERSTATE 90 CORRIDOR BETWEEN 22.03Z AND
22.09Z. HOWEVER IF THE BOUNDARY DOES NOT LIFT AS FAR NORTH AS THE
MESO MODELS INDICATE...THIS CONVECTION COULD POTENTIALLY BE
FURTHER SOUTH TONIGHT.
FLASH FLOODING IS ALSO A CONCERN TONIGHT AS WARM CLOUD LAYER
DEPTHS CLIMB INTO THE 4 TO 4.5 KM RANGE AND PRECIPITABLE WATER
VALUES CLIMB INTO THE 1.8 TO 2.0 INCH RANGE. WITH THE LOW LEVEL
JET CONTINUING TO IMPINGE ON THE FRONT NEAR THE MINNESOTA AND IOWA
BORDER...EXPECT CONVECTION TO CONTINUE TO DEVELOP ACROSS EASTERN
NEBRASKA...WESTERN IOWA AND SOUTHWEST MINNESOTA THROUGHOUT THE
NIGHT. THIS CONVECTION WOULD THEN TRAIN INTO THE FORECAST AREA
WITH THE MEAN WIND. WOULD NOT BE SHOCKED TO SEE 3 TO 5 INCHES OF
RAIN FALL ACROSS PARTS OF THE AREA TONIGHT. THERE MAY BE EVEN SOME
LOCALLY HIGHER AMOUNTS. THIS LOOKS LIKE A CLASSIC MADDOX WARM
FRONTAL FLASH FLOOD EVENT. DUE TO THIS...ISSUED A FLASH FLOOD
WATCH FOR TONIGHT AND SATURDAY MORNING. THE SHOWERS AND
THUNDERSTORMS WILL GRADUALLY DIMINISH ON SATURDAY MORNING AS THE
LOW LEVEL JET WEAKENS.
ON SATURDAY AFTERNOON...THE MODELS SHOW THAT THE WARM FRONT WILL MOVE
NORTHWARD TOWARD THE INTERSTATE 94 CORRIDOR. WITH THERE NOT MUCH
MOISTURE CONVERGENCE ALONG THIS FRONT AND SOME CAPPING
ALOFT...THERE IS A POTENTIAL THAT THE COULD BE SOME DRY HOURS.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 355 PM CDT FRI JUN 21 2013
ON SATURDAY NIGHT...MANY OF THE DETERMINISTIC MODELS SUGGEST THAT
THE 850 MB MOISTURE TRANSPORT WILL SHIFT NORTHEAST OF THE AREA BY
LATE EVENING. AS A RESULT...MANY OF THESE MODELS HAS THE FORECAST
AREA DRYING OUT DURING THE 23.06Z TO 23.12Z TIME FRAME. IF THIS
TREND CONTINUES...MAY HAVE TO LOWER OR POSSIBLY TAKE THESE
PRECIPITATION CHANCES OUT OF THE FORECAST.
FROM SUNDAY INTO TUESDAY...THE MODELS CONTINUE TO STRUGGLE WITH
THE LOCATION OF THE FRONT AND WHERE MESOSCALE COMPLEXES MAY
DEVELOP. AS A RESULT...THE FORECAST CONFIDENCE FOR THE TIMING AND
LOCATION OF THE PRECIPITATION IS NOT AS CERTAIN. DUE TO
THIS...STAYED WITH THE CONSALL PRECIPITATION CHANCES AND ALSO WITH
THEIR MAXIMUM AND MINIMUM TEMPERATURES. ON ANY OF THESE
DAYS...TEMPERATURES COULD EASILY CLIMB INTO THE LOWER 90S IF
ENOUGH SUNSHINE CAN OCCUR.
FROM WEDNESDAY INTO FRIDAY...THE DETERMINISTIC MODELS ARE SHOWING
THAT THE UPPER LEVEL RIDGE WILL RETROGRADE INTO THE WESTERN UNITED
STATES AND WESTERN CANADA. THIS IS IN RESPONSE TO A MODERATE
MADDEN JULIAN OSCILLATION MOVING TOWARD THE INTERNATIONAL DATELINE.
WHEN THIS OCCURS IN SUMMER...CLIMATE PREDICTION CENTER COMPOSITES
FAVOR ABOVE NORMAL TEMPERATURE ANOMALIES ACROSS THE WESTERN UNITED
STATES. AS A RESULT...CONFIDENCE IS HIGH THAT THIS WILL
OCCUR...BUT THE EXACT TIME WHEN THIS WILL ULTIMATELY TAKE PLACE IS
STILL A BIT UNCERTAIN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1212 AM CDT SAT JUN 22 2013
CONVECTION HAS BEEN STEADILY INCREASING SOUTH OF THE TAF SITES
THIS EVENING AS THE LOW LEVEL JET INTERSECTS THE SURFACE BOUNDARY
SITTING ACROSS NORTHEAST IOWA. EXPECT TO SEE THIS AREA FILL IN
WITH CONVECTIVE ACTIVITY AND LIFT TO THE NORTH AND THEN MERGE WITH
THE ACTIVITY COMING IN FROM SOUTHERN MINNESOTA. THIS ACTIVITY
SHOULD THEN PROGRESS EAST ACROSS THE REGION DURING THE LATE NIGHT
HOURS INTO EARLY SATURDAY MORNING. CAN NOT RULE OUT SOME GUSTY
WINDS UNTIL THE MAIN BAND OF STORMS FROM THE WEST PASSES THROUGH
ALONG WITH IFR CONDITIONS IN THE RAIN. ONCE THE MAIN BAND GOES
THROUGH SHOULD CONTINUE TO SEE SOME SHOWERS AND OCCASIONAL
THUNDERSTORMS FOR A COUPLE OF HOURS WITH MVFR CONDITIONS POSSIBLE.
EXPECTING A RETURN TO VFR CONDITIONS ONCE THE RAIN ENDS AND THEN
THE QUESTION BECOMES WHEN AND WHERE THE NEXT ROUND OF CONVECTION
WILL FORM. THE 21.12Z HI-RES ARW HAS BEEN DOING A DECENT JOB IN
THIS PATTERN AND SHOWS THE SURFACE BOUNDARY REMAINING SOUTH OF THE
TAF SITES WITH ACTIVITY DEVELOPING IN THE LATE AFTERNOON AND
CONTINUING INTO THE EVENING AS THE NEXT SHORT WAVE TROUGH COMES
TOWARD THE AREA. CONFIDENCE ON THE TIMING AND PLACEMENT OF THIS IS
NOT HIGH ENOUGH TO GO BEYOND A VCTS AT THIS TIME.
&&
.HYDROLOGY...TONIGHT INTO SATURDAY
ISSUED AT 355 PM CDT FRI JUN 21 2013
OVERNIGHT 1 TO 2 INCHES OF RAIN FELL ACROSS SOUTHEAST
MINNESOTA...AND WEST CENTRAL AND NORTH CENTRAL WISCONSIN...AND
2 TO 4 INCHES FELL ACROSS NORTHEAST IOWA...AND SOUTHWEST AND
CENTRAL WISCONSIN. THIS CAUSED RIVER FLOOD WARNINGS TO BE ISSUED
ALONG THE BLACK AND KICKAPOO RIVERS IN WESTERN WISCONSIN. AS A
STRONG LOW LEVEL JET BRINGS ABUNDANT MOISTURE INTO THE AREA
TONIGHT. EXPECT THAT 3 TO 5 INCHES MAY FALL ACROSS PARTS OF THE
AREA TONIGHT. A FEW LOCAL SPOTS MAY SEE EVEN HIGHER AMOUNTS.
THINKING THAT THE BEST CHANCES ARE ALONG AND NORTH OF THE
INTERSTATE 90 CORRIDOR. HOWEVER THERE IS STILL SOME UNCERTAINTY IN
THIS. THIS ADDITIONAL RAIN WILL LIKELY RESULT IN SOME FLASH
FLOODING TONIGHT. AS A RESULT...WENT WITH A FLASH FLOOD WATCH FOR
THE ENTIRE AREA TONIGHT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR WIZ017-029-
032>034-041>044-053>055-061.
MN...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR MNZ079-086>088-
094>096.
IA...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR IAZ008>011-018-
019-029-030.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...04
HYDROLOGY...BOYNE
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1127 PM MDT FRI JUN 21 2013
.UPDATE...
ISSUED AT 1025 PM MDT FRI JUN 21 2013
CONVECTION CONTINUES TO WIND DOWN ACROSS THE CWA AS THE
ATMOSPHERE STABILIZES. ALTHOUGH A FEW LIGHT SHOWERS AND EMBEDDED
THUNDERSTORMS WILL STILL BE A POSSIBILITY ACROSS EASTERN AND
NORTHERN ZONES THROUGH THE REST OF THE NIGHT...NO LONGER EXPECT
THE POSSIBILITY OF SEVERE WEATHER. SO...HAVE LET THE SEVERE
THUNDERSTORM WATCH EXPIRE AT 10 PM. INITIAL GLANCE AT 00Z MODEL
DATA CONTINUES TO POINT TO ANOTHER ACTIVE DAY ON SATURDAY. HAHN
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 300 PM MDT FRI JUN 21 2013
BELIEVE WE ARE PRIMED FOR A SEVERE WEATHER EPISODE THIS AFTERNOON.
CONDITIONS ARE SET FOR SEVERE THUNDERSTORMS. CHALLENGES ARE WHERE
AND WHEN.
CURRENTLY...STRATUS LAYER ON VISIBLE IMAGERY CONTINUES TO ERODE
ACROSS DAWES AND SIOUX COUNTIES IN THE PANHANDLE AND NIOBRARA
COUNTY IN EAST CENTRAL WYOMING. DEWPOINTS REMAIN EXTREMELY HIGH
(FOR OUR NECK OF THE WOODS)...IN THE PANHANDLE. ALLIANCE STILL
REPORTING A DEW POINT OF 67 DEGREES...WITH LOW TO MID 60S
ELSEWHERE. LATEST STORM PREDICTION CENTER MESOANALYSIS SHOWING
CAPE ALREADY IN MOST OF THE PANHANDLE OF 4500 TO 5000 J/KG. ALL
THAT IS NEEDED IS A LIFTING MECHANISM AND THAT IS DEVELOPING. A
DRY LINE LAYS ACROSS EXTREME SOUTHEASTERN WYOMING...ROUGHLY FROM
JUST EAST OF CHEYENNE TO JUST WEST OF TORRINGTON AND THEN
NORTHWEST TO DOUGLAS. BEHIND THIS LINE...DEWPOINTS HAVE FALLEN
INTO THE 20S. ALONG THIS LINE...SEEING CU DEVELOPING ALONG THE
LINE. HAVE A PRETTY GOOD CELL ALREADY DEVELOPING IN NORTHERN
LARAMIE COUNTY AND SOUTHERN GOSHEN COUNTY. THIS IS MOST LIKELY THE
START OF OUR EVENT. JUST RECEIVED A SWOMCD FROM SPC AT 113 PM STATING
A WATCH IS LIKELY...SO ANOTHER HOUR OR SO...CONVECTION SHOULD
INITIATE.
LATEST HRRR COMPOSITE REFLECTIVITY FORECAST SHOWING THAT CELL IN
SOUTHERN GOSHEN COUNTY TAKING OFF AROUND 3 PM. BY THAT TIME...LOW
STRATUS SHOULD BE MIXED OUT OVER THE NORTHERN PANHANDLE. SUPER CELL
THEN MOVES EAST INTO THE CENTRAL PANHANDLE. WITH SUCH LARGE
CAPE...GOING TO SEE SOME VERY LARGE HAIL REPORTS. NAM/WRF FORECAST
SOUNDINGS CONTINUE TO SHOW STRONGLY VEERING WINDS WITH
NORTHEASTERLY TO EASTERLY SURFACE WINDS AND 35-40KT SOUTHWESTERLY
WINDS AT 700MBS. MORE THAN ENOUGH SHEAR TO SUPPORT SUPERCELLS
CONTINUING INTO THE PANHANDLE. LATEST NAM HELICITIES FOR LATER
THIS AFTERNOON/EVENING SHOWING 150M2/S2...INCREASING TO OVER
300M2/S2 OVER CONVERSE AND NIOBRARA COUNTIES AFTER 00Z...SPREADING
INTO THE NORTHERN PANHANDLE AFTERWARDS. LCLS QUITE LOW UP THERE AS
WELL...SO THE TORNADO THREAT WILL LIKELY BE FROM 23Z THROUGH MAYBE
02 TO 03Z TIME FRAME. SEVERE THUNDERSTORMS COULD LAST WELL INTO THE
EVENING AND OVERNIGHT HOURS IN THE PANHANDLE.
FOR SATURDAY...PRETTY MUCH A REPEAT OF TODAY WITH SEVERE
THUNDERSTORMS OVER EAST CENTRAL WYOMING AND NEBRASKA PANHANDLE.
SHOULD BEGIN TO SEE A DECREASE IN LOW LEVEL MOISTURE SUNDAY AS
WINDS SHIFT TO THE SOUTHWEST. COULD STILL SEE SOME SEVERE
THUNDERSTORMS IN THE PANHANDLE SUNDAY AFTERNOON.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 300 PM MDT FRI JUN 21 2013
DUE TO THE THREAT OF SEVERE WEATHER THIS AFTERNOON...WILL KEEP
LONG TERM DISCUSSION BRIEF SINCE NOT MUCH HAS CHANGED SINCE
YESTERDAY.
MODELS CONTINUING TO SHOW SOUTHWEST FLOW ALOFT AND RELATIVELY
QUIET WEATHER FOR NEXT WEEK. THERE APPEARS TO BE LITTLE IN THE WAY OF
RAINFALL CHANCES ACROSS SOUTHEAST WYOMING NEXT WEEK...WITH A
SLIGHTLY BETTER CHANCE ACROSS WESTERN NEBRASKA ON MONDAY AHEAD OF
A WEAK COOL FRONT. MODELS SHOW THIS PACIFIC FRONT SLIDING
EASTWARD ACROSS THE NORTHERN ROCKIES MONDAY NIGHT AND INTO
TUESDAY. THE GFS AND THE GEM HAVE TRENDED TOWARDS THE ECMWF
SOLUTION...SHOWING THE FRONT STALLING FURTHER TO THE NORTH AS THE
UPPER LEVEL TROUGH IS FURTHER NORTH AS WELL AND MORE PROGRESSIVE.
THE MAIN IMPACT FROM THIS FRONT WILL BE WINDY CONDITIONS...MAINLY
WEST OF THE LARAMIE RANGE ON MONDAY AND TUESDAY. TEMPERATURES WILL
NOT LOWER MUCH...IF AT ALL...ESPECIALLY FURTHER SOUTH NEAR THE I80
CORRIDOR. THERE APPEARS TO BE A BETTER CHANCE OF TSTORMS AHEAD OF
THIS FRONT ON MONDAY...AS A WEAK SHORTWAVE MOVES NORTHEAST ACROSS
THE HIGH PLAINS. INCREASED POP MONDAY AND MONDAY EVENING MAINLY
ACROSS WESTERN NEBRASKA. AFTER THAT...MODELS ALL INDICATE A STRONG
UPPER LEVEL HIGH DEVELOPING AND INTENSIFYING NEAR THE FOUR
CORNERS REGION BY WEDNESDAY AND THURSDAY. THIS WILL RESULT IN A
PERIOD OF LIGHT WINDS BUT ALSO VERY WARM OR HOT TEMPERATURES
THROUGH LATE NEXT WEEK. WITH THE EXCEPTION OF MONDAY...KEPT POP
BELOW 10 PERCENT THROUGH THE WEEK. HIGH TEMPERATURES WILL CONTINUE
TO BE ABOVE NORMAL AND GENERALLY IN THE 80S AND 90S. THIS UPPER
LEVEL HIGH WILL BEGIN TO DRIFT WESTWARD BY LATE IN THE
WEEK...ALLOWING A CANADIAN COLD FRONT TO PUSH SOUTH. THIS MAY
INCREASE PRECIPITATION AND TSTORM CHANCES BY NEXT WEEKEND DUE
FAVORABLE EASTERLY FLOW BEHIND THE BOUNDARY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY EVENING)
ISSUED AT 1127 PM MDT FRI JUN 21 2013
VFR EXPECTED ACROSS SE WYOMING THROUGH SAT MORNING. SCTD SHOWERS
AND A FEW STORMS WILL CONTINUE OVER PARTS OF THE PANHANDLE THROUGH
09Z WITH RESIDUAL MOISTURE POSSIBLY PRODUCING SOME SCTD IFR CIGS AFT
09Z UNTIL ABOUT 15Z. SCTD SHOWERS AND STORMS EXPECTED AGAIN SAT
AFTERNOON AND EVENING MAINLY OVER THE PANHANDLE.
&&
.FIRE WEATHER...
ISSUED AT 300 PM MDT FRI JUN 21 2013
DRY AND BREEZY CONDITIONS CONTINUE ALONG AND WEST OF THE LARAMIE
RANGE THIS AFTERNOON. TO THE EAST IN THE PANHANDLE AND UP OVER
NIOBRARA COUNTY...HIGH HUMIDITIES WILL LEAD TO SEVERE
THUNDERSTORMS LATER THIS AFTERNOON AND EVENING. HUMIDITIES OUT
WEST ONCE AGAIN IN THE SINGLE DIGITS WITH WIND GUSTS FROM THE
SOUTHWEST AT 30 TO 35 MPH. WINDS WILL EASE AFTER SUNSET.
CONDITIONS LOOK TO REPEAT FOR SATURDAY AND TO A LESSER EXTENT ON
SUNDAY AFTERNOON. STRONG WINDS WILL CONTINUE NEXT
WEEK...PARTICULARLY MONDAY NIGHT INTO TUESDAY WITH WIND GUSTS
EXCEEDING 40 MPH POSSIBLE OUT WEST.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...HAHN
SHORT TERM...CLAYCOMB
LONG TERM...TJT
AVIATION...RE
FIRE WEATHER...CLAYCOMB
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1025 PM MDT FRI JUN 21 2013
.UPDATE...
ISSUED AT 1025 PM MDT FRI JUN 21 2013
CONVECTION CONTINUES TO WIND DOWN ACROSS THE CWA AS THE
ATMOSPHERE STABILIZES. ALTHOUGH A FEW LIGHT SHOWERS AND EMBEDDED
THUNDERSTORMS WILL STILL BE A POSSIBILITY ACROSS EASTERN AND
NORTHERN ZONES THROUGH THE REST OF THE NIGHT...NO LONGER EXPECT
THE POSSIBILITY OF SEVERE WEATHER. SO...HAVE LET THE SEVERE
THUNDERSTORM WATCH EXPIRE AT 10 PM. INITIAL GLANCE AT 00Z MODEL
DATA CONTINUES TO POINT TO ANOTHER ACTIVE DAY ON SATURDAY. HAHN
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 300 PM MDT FRI JUN 21 2013
BELIEVE WE ARE PRIMED FOR A SEVERE WEATHER EPISODE THIS AFTERNOON.
CONDITIONS ARE SET FOR SEVERE THUNDERSTORMS. CHALLENGES ARE WHERE
AND WHEN.
CURRENTLY...STRATUS LAYER ON VISIBLE IMAGERY CONTINUES TO ERODE
ACROSS DAWES AND SIOUX COUNTIES IN THE PANHANDLE AND NIOBRARA
COUNTY IN EAST CENTRAL WYOMING. DEWPOINTS REMAIN EXTREMELY HIGH
(FOR OUR NECK OF THE WOODS)...IN THE PANHANDLE. ALLIANCE STILL
REPORTING A DEW POINT OF 67 DEGREES...WITH LOW TO MID 60S
ELSEWHERE. LATEST STORM PREDICTION CENTER MESOANALYSIS SHOWING
CAPE ALREADY IN MOST OF THE PANHANDLE OF 4500 TO 5000 J/KG. ALL
THAT IS NEEDED IS A LIFTING MECHANISM AND THAT IS DEVELOPING. A
DRY LINE LAYS ACROSS EXTREME SOUTHEASTERN WYOMING...ROUGHLY FROM
JUST EAST OF CHEYENNE TO JUST WEST OF TORRINGTON AND THEN
NORTHWEST TO DOUGLAS. BEHIND THIS LINE...DEWPOINTS HAVE FALLEN
INTO THE 20S. ALONG THIS LINE...SEEING CU DEVELOPING ALONG THE
LINE. HAVE A PRETTY GOOD CELL ALREADY DEVELOPING IN NORTHERN
LARAMIE COUNTY AND SOUTHERN GOSHEN COUNTY. THIS IS MOST LIKELY THE
START OF OUR EVENT. JUST RECEIVED A SWOMCD FROM SPC AT 113 PM STATING
A WATCH IS LIKELY...SO ANOTHER HOUR OR SO...CONVECTION SHOULD
INITIATE.
LATEST HRRR COMPOSITE REFLECTIVITY FORECAST SHOWING THAT CELL IN
SOUTHERN GOSHEN COUNTY TAKING OFF AROUND 3 PM. BY THAT TIME...LOW
STRATUS SHOULD BE MIXED OUT OVER THE NORTHERN PANHANDLE. SUPER CELL
THEN MOVES EAST INTO THE CENTRAL PANHANDLE. WITH SUCH LARGE
CAPE...GOING TO SEE SOME VERY LARGE HAIL REPORTS. NAM/WRF FORECAST
SOUNDINGS CONTINUE TO SHOW STRONGLY VEERING WINDS WITH
NORTHEASTERLY TO EASTERLY SURFACE WINDS AND 35-40KT SOUTHWESTERLY
WINDS AT 700MBS. MORE THAN ENOUGH SHEAR TO SUPPORT SUPERCELLS
CONTINUING INTO THE PANHANDLE. LATEST NAM HELICITIES FOR LATER
THIS AFTERNOON/EVENING SHOWING 150M2/S2...INCREASING TO OVER
300M2/S2 OVER CONVERSE AND NIOBRARA COUNTIES AFTER 00Z...SPREADING
INTO THE NORTHERN PANHANDLE AFTERWARDS. LCLS QUITE LOW UP THERE AS
WELL...SO THE TORNADO THREAT WILL LIKELY BE FROM 23Z THROUGH MAYBE
02 TO 03Z TIME FRAME. SEVERE THUNDERSTORMS COULD LAST WELL INTO THE
EVENING AND OVERNIGHT HOURS IN THE PANHANDLE.
FOR SATURDAY...PRETTY MUCH A REPEAT OF TODAY WITH SEVERE
THUNDERSTORMS OVER EAST CENTRAL WYOMING AND NEBRASKA PANHANDLE.
SHOULD BEGIN TO SEE A DECREASE IN LOW LEVEL MOISTURE SUNDAY AS
WINDS SHIFT TO THE SOUTHWEST. COULD STILL SEE SOME SEVERE
THUNDERSTORMS IN THE PANHANDLE SUNDAY AFTERNOON.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 300 PM MDT FRI JUN 21 2013
DUE TO THE THREAT OF SEVERE WEATHER THIS AFTERNOON...WILL KEEP
LONG TERM DISCUSSION BRIEF SINCE NOT MUCH HAS CHANGED SINCE
YESTERDAY.
MODELS CONTINUING TO SHOW SOUTHWEST FLOW ALOFT AND RELATIVELY
QUIET WEATHER FOR NEXT WEEK. THERE APPEARS TO BE LITTLE IN THE WAY OF
RAINFALL CHANCES ACROSS SOUTHEAST WYOMING NEXT WEEK...WITH A
SLIGHTLY BETTER CHANCE ACROSS WESTERN NEBRASKA ON MONDAY AHEAD OF
A WEAK COOL FRONT. MODELS SHOW THIS PACIFIC FRONT SLIDING
EASTWARD ACROSS THE NORTHERN ROCKIES MONDAY NIGHT AND INTO
TUESDAY. THE GFS AND THE GEM HAVE TRENDED TOWARDS THE ECMWF
SOLUTION...SHOWING THE FRONT STALLING FURTHER TO THE NORTH AS THE
UPPER LEVEL TROUGH IS FURTHER NORTH AS WELL AND MORE PROGRESSIVE.
THE MAIN IMPACT FROM THIS FRONT WILL BE WINDY CONDITIONS...MAINLY
WEST OF THE LARAMIE RANGE ON MONDAY AND TUESDAY. TEMPERATURES WILL
NOT LOWER MUCH...IF AT ALL...ESPECIALLY FURTHER SOUTH NEAR THE I80
CORRIDOR. THERE APPEARS TO BE A BETTER CHANCE OF TSTORMS AHEAD OF
THIS FRONT ON MONDAY...AS A WEAK SHORTWAVE MOVES NORTHEAST ACROSS
THE HIGH PLAINS. INCREASED POP MONDAY AND MONDAY EVENING MAINLY
ACROSS WESTERN NEBRASKA. AFTER THAT...MODELS ALL INDICATE A STRONG
UPPER LEVEL HIGH DEVELOPING AND INTENSIFYING NEAR THE FOUR
CORNERS REGION BY WEDNESDAY AND THURSDAY. THIS WILL RESULT IN A
PERIOD OF LIGHT WINDS BUT ALSO VERY WARM OR HOT TEMPERATURES
THROUGH LATE NEXT WEEK. WITH THE EXCEPTION OF MONDAY...KEPT POP
BELOW 10 PERCENT THROUGH THE WEEK. HIGH TEMPERATURES WILL CONTINUE
TO BE ABOVE NORMAL AND GENERALLY IN THE 80S AND 90S. THIS UPPER
LEVEL HIGH WILL BEGIN TO DRIFT WESTWARD BY LATE IN THE
WEEK...ALLOWING A CANADIAN COLD FRONT TO PUSH SOUTH. THIS MAY
INCREASE PRECIPITATION AND TSTORM CHANCES BY NEXT WEEKEND DUE
FAVORABLE EASTERLY FLOW BEHIND THE BOUNDARY.
&&
.AVIATION...(FOR THE 00Z TAF ISSUANCE)
VFR CONDITIONS EXPECTED ALONG AND WEST OF INTERSTATE 25 THROUGH
TONIGHT FOR SOUTHEAST WYOMING...ALTHOUGH SOME LOW CIGS MAY DEVELOP
NEAR THE CHEYENNE RIDGE INCLUDING KCYS AFTER 09Z. STRONG TO SEVERE
THUNDERSTORMS WILL CONTINUE EARLY THIS EVENING ACROSS WESTERN
NEBRASKA AND EXTREME EASTERN WYOMING. ERRATIC GUSTY WINDS UP TO 50
MPH...HAIL...AND IFR CONDITIONS HAVE BEEN REPORTED LATE THIS
AFTERNOON...AND MAY CONTINUE WITH THESE THUNDERSTORMS EAST OF A LINE
FROM KIMBALL NEBRASKA TO LUSK WYOMING. THUNDERSTORMS WILL LINGER
THROUGH LATE TONIGHT BEFORE PUSHING EAST OF THE AREA BY MIDNIGHT.
IFR CONDITIONS IN LOW CIGS AND FOG ARE EXPECTED TO RETURN AFTER
MIDNIGHT ACROSS THE HIGH PLAINS OF WESTERN NEBRASKA AND PORTIONS OF
SOUTHEAST WYOMING.
&&
.FIRE WEATHER...
ISSUED AT 300 PM MDT FRI JUN 21 2013
DRY AND BREEZY CONDITIONS CONTINUE ALONG AND WEST OF THE LARAMIE
RANGE THIS AFTERNOON. TO THE EAST IN THE PANHANDLE AND UP OVER
NIOBRARA COUNTY...HIGH HUMIDITIES WILL LEAD TO SEVERE
THUNDERSTORMS LATER THIS AFTERNOON AND EVENING. HUMIDITIES OUT
WEST ONCE AGAIN IN THE SINGLE DIGITS WITH WIND GUSTS FROM THE
SOUTHWEST AT 30 TO 35 MPH. WINDS WILL EASE AFTER SUNSET.
CONDITIONS LOOK TO REPEAT FOR SATURDAY AND TO A LESSER EXTENT ON
SUNDAY AFTERNOON. STRONG WINDS WILL CONTINUE NEXT
WEEK...PARTICULARLY MONDAY NIGHT INTO TUESDAY WITH WIND GUSTS
EXCEEDING 40 MPH POSSIBLE OUT WEST.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...HAHN
SHORT TERM...CLAYCOMB
LONG TERM...TJT
AVIATION...TJT
FIRE WEATHER...CLAYCOMB
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1038 PM MDT SUN JUN 23 2013
.UPDATE...
ISSUED AT 447 PM MDT SUN JUN 23 2013
UPDATED TO ISSUE A SEVERE THUNDERSTORM WATCH FOR AREAS EAST OF A
LINE FROM COLORADO SPRINGS TO SPRINGFIELD. THIS WATCH GOES THROUGH
MIDNIGHT. THE MAIN THREATS WILL BE LIGHTNING...DAMAGING OUTFLOW
WIND GUSTS AND HAIL TO ONE INCH IN DIAMETER. MOZLEY
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 227 PM MDT SUN JUN 23 2013
...CONTINUED DANGEROUS FIRE WEATHER CONDITIONS...
CURRENTLY...SMOKE FROM THE WEST FORK COMPLEX IS STARTING TO SHIFT
EAST ACROSS THE SAN LUIS VALLEY AND SHOULD CONTINUE TO PUSH EAST
THROUGH THE EVENING. RADAR HAS BEEN PRETTY QUIET WITH A FEW CELLS
BUBBLING NEAR THE SPANISH PEAKS/WALSENBURG AREA. SOUTHEASTERLY
SURFACE FLOW HAS KEPT MOISTURE IN PLACE ACROSS THE PLAINS WITH DEW
POINTS IN THE 40S TO MID 50S. TEMPERATURES ARE WARM WITH UPPER 80S
TO LOWER 90S FOR THE LOWER ELEVATIONS.
TONIGHT...MAIN CONCERN FOR THIS EVENING WILL BE THE POTENTIAL FOR
SEVERE THUNDERSTORMS ACROSS THE PLAINS. CUMULUS HAVE BEEN
PERCOLATING ACROSS THE RAMPART RANGE AND EASTERN MOUNTAINS THIS
AFTERNOON AND AS AN UPPER LEVEL DISTURBANCE MOVES THROUGH THE
SOUTHWEST FLOW ALOFT...IT WILL LIKELY TRIGGER ISOLATED
THUNDERSTORMS. FOLLOWED A BLEND OF THE WRF SOLUTIONS AND HRRR WHICH
DEVELOP SPOTTY CONVECTION FROM COLORADO SPRINGS...SOUTHEAST TO
SPRINGFIELD AND TRACK THEM EAST ACROSS THE PLAINS THROUGH 05Z.
UPDRAFT HELICITY VALUES ARE WEAK BASED ON THE NSSL WRF SOLUTION AND
SHEARS ARE ONLY RUNNING AROUND 30 KTS SO CURRENTLY THINKING THE MAIN
THREATS WILL BE HAIL TO ONE INCH IN DIAMETER AND STRONG THUNDERSTORM
OUTFLOW WINDS. THE TORNADO THREAT LOOKS TO REMAIN NORTH IN
NORTHEAST COLORADO. EXPECT ALL ACTIVITY TO SHIFT EAST INTO KANSAS
THROUGH 06Z WITH DRY CONDITIONS THE REST OF THE NIGHT.
MONDAY...AN UPPER TROUGH WILL MOVE OUT OF THE PACIFIC NORTHWEST
WHICH WILL INCREASE SOUTHWESTERLY FLOW ACROSS COLORADO. THIS WILL
SET THE STAGE FOR WIDESPREAD EXTREME FIRE WEATHER CONDITIONS WITH
WINDS GUSTING TO 30 TO 40 MPH...AND HUMIDITY VALUES WELL UNDER 10
PERCENT. EXTREME CAUTION IS ADVISED ACROSS ALL OF SOUTHERN
COLORADO...BUT PARTICULARLY OVER THE MOUNTAIN REGIONS AND AREAS
ALONG AND WEST OF I-25. THE STRONG WINDS SHOULD ALSO ALLOW
TEMPERATURES TO WARM QUICKLY INTO TO THE UPPER 90S TO LOWER 100S
ACROSS THE PLAINS. SMOKE FROM AREA FIRES WILL SPREAD ACROSS MUCH OF
THE AREA BY THE AFTERNOON WITH REDUCED VISIBILITIES AND POOR AIR
QUALITY. MOZLEY
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 227 PM MDT SUN JUN 23 2013
THERE COULD BE A FEW SHOWERS/TSTMS ALONG THE ERN BORDER EARLY MON
EVENING...BUT WL LEAVE THE FORECAST DRY OUT THERE FOR NOW. DRY
WESTERLY FLOW IS EXPECTED OVR THE FORECAST AREA ON TUE. IT LOOKS
LIKE LOW LEVEL MSTR OVR THE ERN SAN JUAN AND LA GARITA MTNS MAY BE
A LITTLE HIGHER ON TUE...KEEPING MIN RH VALUES HIGH ENOUGH THAT A
FIRE WX HIGHLIGHT SHOULD NOT BE NEEDED FOR THAT AREA. HOWEVER
THERE IS A CHANCE THAT THE WINDS WL BE STRONG ENOUGH...ALONG WITH
DRY ENOUGH HUMIDITIES OVER THE SAN LUIS VALLEY (FIRE ZONE 224) AND
ALONG THE SANGRE DE CRISTO MTNS (FIRE ZONE 225)...TO WARRANT A FIRE
WEATHER WATCH. THE REST OF THE AREA SHOULD NOT HAVE STRONG ENOUGH
WINDS TO WARRANT A FIRE HIGHLIGHT.
FOR WED AN UPR RIDGE CENTER IS EXPECTED TO BE OVR THE WEST CENTRAL
NM...WITH THE FLOW ALOFT OVR THE FORECAST AREA BECOMING MORE
NORTHWESTERLY. STILL LOOKS DRY ACRS THE AREA...WITH MAYBE JUST A
COUPLE SHOWERS/TSTMS POPPING UP OVR SOME MTN LOCATIONS. THE UPR
RIDGE THEN REMAINS OVR THE AREA THU THRU SAT WITH MODELS
INDICATING SOME MSTR TRAPPED UNDER THE RIDGE AND THE POTENTIAL FOR
JUST A FEW SHOWERS/TSTMS OVR AND NR THE MTNS. THE GFS SHOWS THE
POTENTIAL FOR A WEATHER SYSTEM MOVING BY TO THE NORTH SAT
NIGHT/SUN FLATTENING THE RIDGE AND SENDING A FRONT INTO THE AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1031 PM MDT SUN JUN 23 2013
THE MAIN AVN CONCERN TOMORROW WILL BE INCREASED SOUTHWEST
WINDS OVER THE AREA FROM LATE MORNING THROUGH EARLY EVENING.
WINDS COULD GUST IN THE 30-40 MPH RANGE BY LATE AFTERNOON...
PARTICULARLY AT KALS AND KCOS. THE SOUTHWEST WINDS ALOFT
WILL ALSO LEAD TO INCREASED SMOKE AT ALL TERMINALS IN THE
AFTERNOON AND EVENING. DEPENDING ON HOW ACTIVE THE WEST FORK
FIRE COMPLEX GETS...VISIBILITY MAY DROP TO MVFR OR LOWER
AGAIN BY EARLY EVENING. ROSE
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 11 AM TO 8 PM MDT MONDAY FOR COZ220>230.
FIRE WEATHER WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING
FOR COZ224-225.
&&
$$
UPDATE...MOZLEY
SHORT TERM...MOZLEY
LONG TERM...28
AVIATION...ROSE
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
319 AM CDT MON JUN 24 2013
.DISCUSSION...
723 PM CDT
MADE MINOR TWEAKS TO THE GOING FORECAST. CONVECTION HAS SUBSIDED
WITH SHOWERS FROM CHICAGO THROUGH STREATOR. EXPECTING THE SHOWERS
TO SLOWLY WEAKEN AND MOVE EASTWARD...PRODUCING UP TO AN ADDITIONAL
TENTH OF AN INCH OF PRECIP. THE CONVECTIVE OUTFLOW COOLED AREAS
BUT MOST PLACES HAVE REBOUNDED...SO ADJUSTED TEMPS TRENDS BUT DID
NOT MAKE MAJOR CHANGES TO LOW TEMPS TONIGHT.
AS FAR AS PRECIP CHANCES THROUGH THE REST OF THE NIGHT...MADE
MINOR ADJUSTMENTS BUT THE OVERALL PICTURE REMAINS THE SAME.
EXPECTING CONVECTION TO REFIRE IN THE FOUR CORNERS AREA OF
NE/IA/MO/KS AND SPREAD ACROSS IA OVERNIGHT. STEERING FLOW WOULD
DIRECT THE STORMS TO THE EAST WITH STORMS ENTERING AREAS ALONG AND
WEST OF THE I-39 CORRIDOR AROUND/AFTER 09Z. HOWEVER CONFIDENCE IS
LOW TO MEDIUM IN HOW CONVECTION WILL EVOLVE AND LOW IN TIMING.
HEAVY RAIN IS A DEFINITE CONCERN...BUT DUE TO LOW CONFIDENCE IN
THE CONVECTIVE EVOLUTION I WILL HOLD OFF ISSUING A FLASH FLOOD
WATCH. LIGHTNING...GUSTY WINDS...AND SMALL HAIL ARE ALSO
POSSIBLE...BUT THINKING SEVERE WEATHER WILL BE ISOLATED AT BEST
DUE TO THE ELEVATED NATURE OF THE STORMS.
JEE
//PREV DISCUSSION...
304 PM CDT
SHOWER/THUNDER CHANCES REMAIN THE BIGGEST FORECAST CHALLENGE
FOLLOWED BY TEMPS WHICH MAY BE AFFECTED BY THE CONVECTION. AFTERNOON
WATER VAPOR IMAGERY SHOWS ONE UPPER LEVEL LOW SPINNING OVER THE
CENTRAL APPALACHIANS WHICH IS LOSING DEFINITION AS IS MOVES SLOWLY
NORTHWARD. THE NEXT UPPER LOW IS SPINNING OVER THE SOUTHERN
CANADIAN PRAIRIES WITH A TROUGH AXIS EXTENDING INTO THE DAKOTAS AND
LIFTING NORTHEAST. THE UPPER FLOW IS LESS AMPLIFIED FURTHER SOUTH OF
THE LOW ACROSS THE CENTRAL PLAINS BUT THERE ARE SEVERAL EMBEDDED
WAVES THAT ARE TRANSLATING NORTHEAST AS WELL. THE NEXT UPPER LOW OF
NOTE IS COMING ONSHORE OVER THE WEST COAST AND HELPING TO AMPLIFY A
RIDGE OVER OREGON/WASHINGTON. ENERGY EMANATING FROM THIS TROUGH WILL
BECOME A PLAYER IN OUR WEATHER LATER THIS WEEK. AT THE SURFACE...LOW
PRESSURE IS POSITIONED OVER NORTHWEST MINNESOTA WITH WEAKER LOW
PRESSURE SPREAD ACROSS THE PLAINS. A COOL FRONTAL BOUNDARY IS
STRETCHED FROM THE MN LOW BUT HAS BECOME DIFFICULT TO IDENTIFY
THANKS TO COLD POOLS FROM MORNING CONVECTION.
THROUGH THIS EVENING...TOUGH FORECAST ONCE AGAIN IN TERMS OF
CONVECTIVE POTENTIAL AND EVOLUTION THROUGH THE PERIOD. OUTFLOW
BOUNDARY FROM EARLIER IOWA CONVECTION IS NOW PUSHING INTO THE
WESTERN CWA TRIGGERING THUNDERSTORMS ALONG IT. A BETTER ORGANIZED
COMPLEX OF STORMS HAS DEVELOPED FROM THE EARLIER CONVECTION BUT IS
MOVING SOUTHEAST ACROSS NORTHERN MISSOURI INTO THE AXIS OF MUCH
BETTER INSTABILITY AS WELL AS BETTER MID LEVEL MOISTURE
ADVECTION. ADDITIONAL SCATTERED STORMS HAVE DEVELOPED OVER THE
SOUTHERN CWA LIKELY IN BETTER CONJUNCTION WITH THE WEAKENING UPPER
LOW OVER APPALACHIA. IN THE NEAR TERM...EXPECT THE OUTFLOW TO
CONTINUE EASTWARD ACROSS THE CWA TRIGGERING SCATTERED STORMS THROUGH
LATE AFTERNOON/EARLY EVENING. MESOANALYSIS SHOWS 2000+ J/KG OF MIXED
LAYER CAPE OVER THE AREA SUPPORTING STRONG UPDRAFTS BUT DEEP LAYER
SHEAR IS WEAK SO CORES SHOULD BE PRETTY PULSEY. LARGE HAIL AND
LOCALLY HEAVY DOWNPOURS ARE THE MAIN CONCERN. GUSTY WINDS ARE ALSO
POSSIBLE BUT RECENT AIRCRAFT SOUNDINGS FROM MDW DO NOT SHOW A TON OF
DRY LOW LEVEL AIR AND RAP ANALYSIS OF DCAPE IS LOW AS WELL. WOULD
EXPECT THAT THIS ACTIVITY WOULD WANE WITH SUNSET.
REST OF TONIGHT AND MONDAY...ATTENTION TURNS TO ADDITIONAL
CONVECTIVE POTENTIAL OVERNIGHT. WATER VAPOR SHOWS A WAVE OVER NE
KS/NW MO WHICH APPEARS TO BE TURNING MORE EASTWARD IN THE LAST FEW
SCANS. THIS IS LIKELY HELPING THE COMPLEX TAKING SHAPE OVER MO.
SHORT TERM/HIGH RES GUIDANCE HAS BEEN ALL OVER THE PLACE WITH HOW
CONVECTION EVOLVES THROUGH TONIGHT. THE MOIST SOUTHWESTERLY FLOW
WILL CONTINUE ACROSS THE REGION TONIGHT AND THE EARLIER COLD FRONTAL
BOUNDARY SEEMS TO BE DEVELOPING ONCE AGAIN ACROSS IOWA AS THE FLOW
HAS SETTLED FROM EARLIER CONVECTION. THIS IS SUPPORTIVE OF NEW
DEVELOPMENT TO THE WEST TONIGHT. THE OUTFLOW CURRENTLY WORKING INTO
THE LOCAL AREA EXTENDS INTO WEST-CENTRAL ILLINOIS AND THERE ARE
HINTS THAT THE SOUTHERN EXTENT OF IT AND LIKELY A BOUNDARY SET UP BY
THE CURRENT COMPLEX MAY STALL OUT SOMEWHERE NOT FAR FROM THE
SOUTHWESTERN CWA. IN ADDITION...THE KS/MO WAVE IS EXPECTED TO CROSS
THIS SAME AREA TONIGHT WHICH IS ALSO EXPECTED TO BE IN AN AREA OF
MID LEVEL WARM ADVECTION. THEREFORE IT IS POSSIBLE ROUNDS OF
CONVECTION COULD DEVELOP TO THE SOUTHWEST OF THE AREA AND ROLL
EASTWARD INTO THE SOUTHERN CWA OVERNIGHT. HAVE NOT MADE MUCH CHANGE
TO OVERNIGHT POPS BUT DID INCREASE THEM SOMEWHAT OVER THE FAR SOUTH.
AS FOR MONDAY...GUIDANCE REMAINS IN POOR AGREEMENT WITH TRACK OF
POTENTIAL UPPER WAVES BUT WATER VAPOR DOES SHOW SOME SIGNS OF A WAVE
COMING ACROSS THE FOUR CORNERS THIS AFTERNOON. THIS WOULD COME ACROSS
THE REGION LATER MONDAY BUT IT IS NOT CLEAR IF IT WILL BE MORE
FOCUSED TO THE NORTH OF THE AREA. WILL CONTINUE WITH MID CHANCE POPS
WITH LATER IN THE DAY MORE FAVORED. PROVIDED THE LATER TIMING WORKS
OUT THEN WE WILL HAVE A BETTER CHANCE TO WARM BUT THERE MAY BE
CONVECTIVE DEBRIS AROUND SO WILL HOLD TEMPS INTO THE MID 80S FOR
MOST AREAS.
TUESDAY THROUGH SUNDAY...THE UPPER FLOW BECOMES LESS AMPLIFIED
TUESDAY BUT WILL LIKELY STILL BE LITTERED WITH WAVES TRAVERSING IT.
HOT AND HUMID AIR WILL STILL BE IN PLACE WITH PRECIPITABLE WATER
VALUES HOVERING AROUND 1.75 INCHES. THESE FACTORS PROVIDE CONTINUED
SUPPORT FOR THUNDERSTORM DEVELOPMENT BUT THERE IS NOT MUCH TO KEY IN
ON FOR A COHERENT FORCING MECHANISM GIVEN THE LOW AMPLITUDE PATTERN.
BY WEDNESDAY...THERE IS SOME AGREEMENT ON SURFACE LOW PRESSURE
HAVING DEVELOPED ACROSS THE CANADIAN PRAIRIES WITH A TROUGH
AXIS/FRONT EXTENDING INTO MINNESOTA AND IOWA...WITH A SECONDARY LOW
POSSIBLY DEVELOPING ACROSS MINNESOTA. THE FRONT LOOKS TO CROSS THE
AREA LATER WEDNESDAY BRINGING SHOWER AND STORM CHANCES WITH IT.
UPPER RIDGING WILL BE BUILDING ACROSS THE WESTERN U.S. AND HIGH
PLAINS WITH A WAVE ORIGINATING FROM THE TROUGH OFF THE WEST COAST
OVERTOPPING THE RIDGE ACROSS THE CANADIAN ROCKIES AND DROPPING
SOUTHEASTWARD INTO THE GREAT LAKES WHILE AMPLIFYING LATE IN THE
WEEK. GFS AND ECMWF DIFFER ON HOW QUICKLY THIS OCCURS BUT THE SIGNAL
HAS BEEN CONSISTENT OVERALL. THIS WILL BRING A SHIFT TO
NORTHWESTERLY AT THE SURFACE AND ALOFT LATE IN THE WEEK AND
NOTICEABLY COOLER TEMPERATURES BY SATURDAY OR SO. LOW POPS WILL
CONTINUE WITH THE FLOW CONTINUING TO FAVOR WEAK SHORTWAVE PASSAGES.
HIGH TEMPS WILL LIKELY HOVER AROUND 90 TUESDAY AND WEDNESDAY
ASSUMING CONVECTION OR CONVECTIVE DEBRIS IS NOT AN ISSUE...WHICH
WOULD SIGNIFICANTLY LOWER HIGHS IF IT IS. WITH THE PASSAGE OF THE
SYSTEM LATER WEDNESDAY COOLER MID LEVEL AIR WILL FILTER IN KEEPING
HIGHS BACK IN THE 80S WITH UPPER 70S POSSIBLE FRIDAY AND SATURDAY.
MDB
&&
.HYDROLOGY...
745 PM CDT
THE CONVECTIVE ACTIVITY THIS EVENING PRODUCED ISOLATED AREAS OF 2+
INCHES OF RAIN AND A BAND OF 1+ INCHES OF RAIN ACROSS LA SALLE
COUNTY. STILL CONSIDERED A FLASH FLOOD WATCH FOR THE WEST AND FAR
SOUTHWEST CWA GIVEN THE RAINFALL OF THE PAST FEW DAYS. CONFIDENCE
REMAINS LOW IN WHERE ORGANIZED CONVECTION WILL SET UP TONIGHT AND
MONDAY SO WILL HOLD OFF UNTIL AREAS AND TIMING CAN BE BETTER
DEFINED.
JEE/MDB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* MAINLY SOUTHERLY WINDS ARND 10KT...OCCASIONAL GUSTS LATE
MORNING/AFTN TO 20-24KT. IF TSRA DEVELOP WIND DIR COULD BECOME
VRB FOR A PERIOD OF TIME.
* PRECIP DEVELOPS...LOW COVERAGE EXPECTED LATE THIS MORNING THRU
AFTN.
BEACHLER
//DISCUSSION...UPDATED 06Z...
SIMILAR SETUP AGAIN TODAY AS HAS BEEN THE CASE THE PAST FEW
DAYS...ISOLATED TSRA DEVELOPING. EXPECT MAINLY SOUTHERLY WINDS
ARND 10KT INCREASING WITH GUSTS TO 20-24KT BY LATE MORNING THRU
THE AFTN. THE WILDCARD WILL BE CLOUD COVER WHICH COULD LIMIT HOW
GUSTY WINDS BECOME. THEN THE FOCUS TURNS TOWARDS TIMING OF
PRECIP DEVELOPMENT. EARLY THIS MORNING AN AREA OF SHRA/TSRA WAS
PULSING NORTHEAST...HOWEVER IT DOES NOT APPEAR THIS SHOULD HOLD
TOGETHER AND IMPACT THE TAF SITES. LATER THIS MORNING A WEAK WAVE
DOES TRY TO PUSH OVERHEAD...AND EXPECT SLOW DEVELOPMENT TO
THUNDERSTORMS MIDDAY/AFTN. THE COVERAGE SHOULD BE MINIMAL AND MORE
OF A PULSE LIKE ENVIRONMENT...WHICH COULD POSE A CHALLENGE FOR A
FEW SITES SEEING CHAOTIC WIND DIR/SPEEDS FOR A BRIEF PERIOD OF
TIME IN/AROUND THUNDERSTORMS.
WINDS THEN BEGIN TO DIMINISH TO ARND 5-7KT OVERNIGHT INTO EARLY
TUE...WITH POSSIBLY A REPEAT WITH ISOLATED SHRA/TSRA IN THE AREA
AFT 06Z TUE.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM CONFIDENCE IN TIMING OF SHRA/TSRA DEVELOPMENT.
* HIGH CONFIDENCE IN MAINLY SOUTHERLY WIND SPEEDS/GUSTS.
* MEDIUM CONFIDENCE VFR CONDS WILL PREVAIL.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...
TUESDAY THROUGH FRIDAY...PERIODIC CHANCES OF TSRA.
SATURDAY...CHANCE OF SHRA.
RODRIGUEZ
&&
.MARINE...
312 AM CDT
MAIN MARINE CONCERNS IS ON DENSE FOG FOR THE NORTHERN HALF OF THE
LAKE...AND POSSIBLY LINGERING THROUGH MID-WEEK. PERIODIC
THUNDERSTORMS CHANCES ARE EXPECTED THROUGH THE NEXT SEVERAL DAYS
AS WELL.
MINIMAL CHANGES TO PREVIOUS FORECASTS...WITH BROAD RIDGE OF HIGH
PRESSURE ANCHORED OVER THE WESTERN ATLANTIC OCEAN...BEGINNING TO
DRIFT SOUTH THROUGH THE NEXT FEW DAYS. A LOW PRESSURE NEAR LAKE
WINNIPEG WILL DRIFT EAST TOWARDS JAMES BAY TUESDAY MORNING...WHILE
ANOTHER AREA OF LOW PRESSURE STRETCHING FROM SOUTHERN CANADA TO
THE CENTRAL PLAINS BEGINS TO DRIFT NORTHEAST WEDNESDAY. THE
COMBINATION OF THE WESTERN ATLANTIC OCEAN RIDGE AND CENTRAL
PLAINS/CANADIAN LOW...WILL MAINTAIN A GENERALLY SOUTHERLY FLOW OF
WARM/MOIST AIR ACROSS LAKE MICHIGAN. THIS SHOULD KEEP ANY FOG OUT
OF THE SOUTHERN ZONES...HOWEVER AREAS OF DENSE FOG WILL REDEVELOP
FOR THE NORTHERN HALF AND COULD EASILY PERSIST THROUGH MID-WEEK.
HAVE EXTENDED THE MARINE FOG ADVISORY THROUGH DAYBREAK TUE...BUT
COULD EASILY SEE THIS NEEDING TO BE EXTENDED EVEN FURTHER OUT IN
TIME. WINDS WILL GENERALLY BE SOUTHERLY TO AT TIMES
SOUTHWESTERLY...WITH SPEEDS OVERNIGHT IN A 10-15KT RANGE AND
INCREASING TO 15 TO 20 KT DURING THE DAY. WITH ANY THUNDERSTORMS
THAT DEVELOP...WINDS AND WAVES WILL EASILY BE HIGHER IN AND AROUND
THESE THUNDERSTORMS.
A COLD FRONT PUSHES ACROSS THE LAKE DURING WEDNESDAY
NIGHT...SHIFTING WINDS TO OUT OF THE WEST. A SECONDARY COLD FRONT
WILL MOVE ACROSS THE LAKE AND SHIFT WINDS TO OUT OF THE NORTHWEST
DURING LATER THURSDAY AND THURSDAY NIGHT.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ008-ILZ010-ILZ011-ILZ019
UNTIL 7 PM MONDAY.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565
UNTIL 10 AM TUESDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1259 AM CDT MON JUN 24 2013
.DISCUSSION...
723 PM CDT
MADE MINOR TWEAKS TO THE GOING FORECAST. CONVECTION HAS SUBSIDED
WITH SHOWERS FROM CHICAGO THROUGH STREATOR. EXPECTING THE SHOWERS
TO SLOWLY WEAKEN AND MOVE EASTWARD...PRODUCING UP TO AN ADDITIONAL
TENTH OF AN INCH OF PRECIP. THE CONVECTIVE OUTFLOW COOLED AREAS
BUT MOST PLACES HAVE REBOUNDED...SO ADJUSTED TEMPS TRENDS BUT DID
NOT MAKE MAJOR CHANGES TO LOW TEMPS TONIGHT.
AS FAR AS PRECIP CHANCES THROUGH THE REST OF THE NIGHT...MADE
MINOR ADJUSTMENTS BUT THE OVERALL PICTURE REMAINS THE SAME.
EXPECTING CONVECTION TO REFIRE IN THE FOUR CORNERS AREA OF
NE/IA/MO/KS AND SPREAD ACROSS IA OVERNIGHT. STEERING FLOW WOULD
DIRECT THE STORMS TO THE EAST WITH STORMS ENTERING AREAS ALONG AND
WEST OF THE I-39 CORRIDOR AROUND/AFTER 09Z. HOWEVER CONFIDENCE IS
LOW TO MEDIUM IN HOW CONVECTION WILL EVOLVE AND LOW IN TIMING.
HEAVY RAIN IS A DEFINITE CONCERN...BUT DUE TO LOW CONFIDENCE IN
THE CONVECTIVE EVOLUTION I WILL HOLD OFF ISSUING A FLASH FLOOD
WATCH. LIGHTNING...GUSTY WINDS...AND SMALL HAIL ARE ALSO
POSSIBLE...BUT THINKING SEVERE WEATHER WILL BE ISOLATED AT BEST
DUE TO THE ELEVATED NATURE OF THE STORMS.
JEE
//PREV DISCUSSION...
304 PM CDT
SHOWER/THUNDER CHANCES REMAIN THE BIGGEST FORECAST CHALLENGE
FOLLOWED BY TEMPS WHICH MAY BE AFFECTED BY THE CONVECTION. AFTERNOON
WATER VAPOR IMAGERY SHOWS ONE UPPER LEVEL LOW SPINNING OVER THE
CENTRAL APPALACHIANS WHICH IS LOSING DEFINITION AS IS MOVES SLOWLY
NORTHWARD. THE NEXT UPPER LOW IS SPINNING OVER THE SOUTHERN
CANADIAN PRAIRIES WITH A TROUGH AXIS EXTENDING INTO THE DAKOTAS AND
LIFTING NORTHEAST. THE UPPER FLOW IS LESS AMPLIFIED FURTHER SOUTH OF
THE LOW ACROSS THE CENTRAL PLAINS BUT THERE ARE SEVERAL EMBEDDED
WAVES THAT ARE TRANSLATING NORTHEAST AS WELL. THE NEXT UPPER LOW OF
NOTE IS COMING ONSHORE OVER THE WEST COAST AND HELPING TO AMPLIFY A
RIDGE OVER OREGON/WASHINGTON. ENERGY EMANATING FROM THIS TROUGH WILL
BECOME A PLAYER IN OUR WEATHER LATER THIS WEEK. AT THE SURFACE...LOW
PRESSURE IS POSITIONED OVER NORTHWEST MINNESOTA WITH WEAKER LOW
PRESSURE SPREAD ACROSS THE PLAINS. A COOL FRONTAL BOUNDARY IS
STRETCHED FROM THE MN LOW BUT HAS BECOME DIFFICULT TO IDENTIFY
THANKS TO COLD POOLS FROM MORNING CONVECTION.
THROUGH THIS EVENING...TOUGH FORECAST ONCE AGAIN IN TERMS OF
CONVECTIVE POTENTIAL AND EVOLUTION THROUGH THE PERIOD. OUTFLOW
BOUNDARY FROM EARLIER IOWA CONVECTION IS NOW PUSHING INTO THE
WESTERN CWA TRIGGERING THUNDERSTORMS ALONG IT. A BETTER ORGANIZED
COMPLEX OF STORMS HAS DEVELOPED FROM THE EARLIER CONVECTION BUT IS
MOVING SOUTHEAST ACROSS NORTHERN MISSOURI INTO THE AXIS OF MUCH
BETTER INSTABILITY AS WELL AS BETTER MID LEVEL MOISTURE
ADVECTION. ADDITIONAL SCATTERED STORMS HAVE DEVELOPED OVER THE
SOUTHERN CWA LIKELY IN BETTER CONJUNCTION WITH THE WEAKENING UPPER
LOW OVER APPALACHIA. IN THE NEAR TERM...EXPECT THE OUTFLOW TO
CONTINUE EASTWARD ACROSS THE CWA TRIGGERING SCATTERED STORMS THROUGH
LATE AFTERNOON/EARLY EVENING. MESOANALYSIS SHOWS 2000+ J/KG OF MIXED
LAYER CAPE OVER THE AREA SUPPORTING STRONG UPDRAFTS BUT DEEP LAYER
SHEAR IS WEAK SO CORES SHOULD BE PRETTY PULSEY. LARGE HAIL AND
LOCALLY HEAVY DOWNPOURS ARE THE MAIN CONCERN. GUSTY WINDS ARE ALSO
POSSIBLE BUT RECENT AIRCRAFT SOUNDINGS FROM MDW DO NOT SHOW A TON OF
DRY LOW LEVEL AIR AND RAP ANALYSIS OF DCAPE IS LOW AS WELL. WOULD
EXPECT THAT THIS ACTIVITY WOULD WANE WITH SUNSET.
REST OF TONIGHT AND MONDAY...ATTENTION TURNS TO ADDITIONAL
CONVECTIVE POTENTIAL OVERNIGHT. WATER VAPOR SHOWS A WAVE OVER NE
KS/NW MO WHICH APPEARS TO BE TURNING MORE EASTWARD IN THE LAST FEW
SCANS. THIS IS LIKELY HELPING THE COMPLEX TAKING SHAPE OVER MO.
SHORT TERM/HIGH RES GUIDANCE HAS BEEN ALL OVER THE PLACE WITH HOW
CONVECTION EVOLVES THROUGH TONIGHT. THE MOIST SOUTHWESTERLY FLOW
WILL CONTINUE ACROSS THE REGION TONIGHT AND THE EARLIER COLD FRONTAL
BOUNDARY SEEMS TO BE DEVELOPING ONCE AGAIN ACROSS IOWA AS THE FLOW
HAS SETTLED FROM EARLIER CONVECTION. THIS IS SUPPORTIVE OF NEW
DEVELOPMENT TO THE WEST TONIGHT. THE OUTFLOW CURRENTLY WORKING INTO
THE LOCAL AREA EXTENDS INTO WEST-CENTRAL ILLINOIS AND THERE ARE
HINTS THAT THE SOUTHERN EXTENT OF IT AND LIKELY A BOUNDARY SET UP BY
THE CURRENT COMPLEX MAY STALL OUT SOMEWHERE NOT FAR FROM THE
SOUTHWESTERN CWA. IN ADDITION...THE KS/MO WAVE IS EXPECTED TO CROSS
THIS SAME AREA TONIGHT WHICH IS ALSO EXPECTED TO BE IN AN AREA OF
MID LEVEL WARM ADVECTION. THEREFORE IT IS POSSIBLE ROUNDS OF
CONVECTION COULD DEVELOP TO THE SOUTHWEST OF THE AREA AND ROLL
EASTWARD INTO THE SOUTHERN CWA OVERNIGHT. HAVE NOT MADE MUCH CHANGE
TO OVERNIGHT POPS BUT DID INCREASE THEM SOMEWHAT OVER THE FAR SOUTH.
AS FOR MONDAY...GUIDANCE REMAINS IN POOR AGREEMENT WITH TRACK OF
POTENTIAL UPPER WAVES BUT WATER VAPOR DOES SHOW SOME SIGNS OF A WAVE
COMING ACROSS THE FOUR CORNERS THIS AFTERNOON. THIS WOULD COME ACROSS
THE REGION LATER MONDAY BUT IT IS NOT CLEAR IF IT WILL BE MORE
FOCUSED TO THE NORTH OF THE AREA. WILL CONTINUE WITH MID CHANCE POPS
WITH LATER IN THE DAY MORE FAVORED. PROVIDED THE LATER TIMING WORKS
OUT THEN WE WILL HAVE A BETTER CHANCE TO WARM BUT THERE MAY BE
CONVECTIVE DEBRIS AROUND SO WILL HOLD TEMPS INTO THE MID 80S FOR
MOST AREAS.
TUESDAY THROUGH SUNDAY...THE UPPER FLOW BECOMES LESS AMPLIFIED
TUESDAY BUT WILL LIKELY STILL BE LITTERED WITH WAVES TRAVERSING IT.
HOT AND HUMID AIR WILL STILL BE IN PLACE WITH PRECIPITABLE WATER
VALUES HOVERING AROUND 1.75 INCHES. THESE FACTORS PROVIDE CONTINUED
SUPPORT FOR THUNDERSTORM DEVELOPMENT BUT THERE IS NOT MUCH TO KEY IN
ON FOR A COHERENT FORCING MECHANISM GIVEN THE LOW AMPLITUDE PATTERN.
BY WEDNESDAY...THERE IS SOME AGREEMENT ON SURFACE LOW PRESSURE
HAVING DEVELOPED ACROSS THE CANADIAN PRAIRIES WITH A TROUGH
AXIS/FRONT EXTENDING INTO MINNESOTA AND IOWA...WITH A SECONDARY LOW
POSSIBLY DEVELOPING ACROSS MINNESOTA. THE FRONT LOOKS TO CROSS THE
AREA LATER WEDNESDAY BRINGING SHOWER AND STORM CHANCES WITH IT.
UPPER RIDGING WILL BE BUILDING ACROSS THE WESTERN U.S. AND HIGH
PLAINS WITH A WAVE ORIGINATING FROM THE TROUGH OFF THE WEST COAST
OVERTOPPING THE RIDGE ACROSS THE CANADIAN ROCKIES AND DROPPING
SOUTHEASTWARD INTO THE GREAT LAKES WHILE AMPLIFYING LATE IN THE
WEEK. GFS AND ECMWF DIFFER ON HOW QUICKLY THIS OCCURS BUT THE SIGNAL
HAS BEEN CONSISTENT OVERALL. THIS WILL BRING A SHIFT TO
NORTHWESTERLY AT THE SURFACE AND ALOFT LATE IN THE WEEK AND
NOTICEABLY COOLER TEMPERATURES BY SATURDAY OR SO. LOW POPS WILL
CONTINUE WITH THE FLOW CONTINUING TO FAVOR WEAK SHORTWAVE PASSAGES.
HIGH TEMPS WILL LIKELY HOVER AROUND 90 TUESDAY AND WEDNESDAY
ASSUMING CONVECTION OR CONVECTIVE DEBRIS IS NOT AN ISSUE...WHICH
WOULD SIGNIFICANTLY LOWER HIGHS IF IT IS. WITH THE PASSAGE OF THE
SYSTEM LATER WEDNESDAY COOLER MID LEVEL AIR WILL FILTER IN KEEPING
HIGHS BACK IN THE 80S WITH UPPER 70S POSSIBLE FRIDAY AND SATURDAY.
MDB
&&
.HYDROLOGY...
745 PM CDT
THE CONVECTIVE ACTIVITY THIS EVENING PRODUCED ISOLATED AREAS OF 2+
INCHES OF RAIN AND A BAND OF 1+ INCHES OF RAIN ACROSS LA SALLE
COUNTY. STILL CONSIDERED A FLASH FLOOD WATCH FOR THE WEST AND FAR
SOUTHWEST CWA GIVEN THE RAINFALL OF THE PAST FEW DAYS. CONFIDENCE
REMAINS LOW IN WHERE ORGANIZED CONVECTION WILL SET UP TONIGHT AND
MONDAY SO WILL HOLD OFF UNTIL AREAS AND TIMING CAN BE BETTER
DEFINED.
JEE/MDB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* MAINLY SOUTHERLY WINDS ARND 10KT...OCCASIONAL GUSTS LATE
MORNING/AFTN TO 20-24KT. IF TSRA DEVELOP WIND DIR COULD BECOME
VRB FOR A PERIOD OF TIME.
* PRECIP DEVELOPS...LOW COVERAGE EXPECTED LATE THIS MORNING THRU
AFTN.
BEACHLER
//DISCUSSION...UPDATED 06Z...
SIMILAR SETUP AGAIN TODAY AS HAS BEEN THE CASE THE PAST FEW
DAYS...ISOLATED TSRA DEVELOPING. EXPECT MAINLY SOUTHERLY WINDS
ARND 10KT INCREASING WITH GUSTS TO 20-24KT BY LATE MORNING THRU
THE AFTN. THE WILDCARD WILL BE CLOUD COVER WHICH COULD LIMIT HOW
GUSTY WINDS BECOME. THEN THE FOCUS TURNS TOWARDS TIMING OF
PRECIP DEVELOPMENT. EARLY THIS MORNING AN AREA OF SHRA/TSRA WAS
PULSING NORTHEAST...HOWEVER IT DOES NOT APPEAR THIS SHOULD HOLD
TOGETHER AND IMPACT THE TAF SITES. LATER THIS MORNING A WEAK WAVE
DOES TRY TO PUSH OVERHEAD...AND EXPECT SLOW DEVELOPMENT TO
THUNDERSTORMS MIDDAY/AFTN. THE COVERAGE SHOULD BE MINIMAL AND MORE
OF A PULSE LIKE ENVIRONMENT...WHICH COULD POSE A CHALLENGE FOR A
FEW SITES SEEING CHAOTIC WIND DIR/SPEEDS FOR A BRIEF PERIOD OF
TIME IN/AROUND THUNDERSTORMS.
WINDS THEN BEGIN TO DIMINISH TO ARND 5-7KT OVERNIGHT INTO EARLY
TUE...WITH POSSIBLY A REPEAT WITH ISOLATED SHRA/TSRA IN THE AREA
AFT 06Z TUE.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM CONFIDENCE IN TIMING OF SHRA/TSRA DEVELOPMENT.
* HIGH CONFIDENCE IN MAINLY SOUTHERLY WIND SPEEDS/GUSTS.
* MEDIUM CONFIDENCE VFR CONDS WILL PREVAIL.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...
TUESDAY THROUGH FRIDAY...PERIODIC CHANCES OF TSRA.
SATURDAY...CHANCE OF SHRA.
RODRIGUEZ
&&
.MARINE...
420 PM CDT
A LARGE AREA OF HIGH PRESSURE EXTENDS FROM THE WESTERN ATLANTIC
SOUTHWESTWARD ACROSS THE SOUTHEASTERN U.S. AND THE NORTHERN GULF
OF MEXICO. THIS HIGH WILL BE MOVING ONLY VERY SLOWLY SOUTHEASTWARD
TONIGHT THROUGH THURSDAY. LOW PRESSURE NEAR LAKE WINNIPEG WILL BE
MOVING SLOWLY EASTWARD ACROSS ONTARIO...REACHING NEAR SOUTHERN JAMES
BAY BY TUESDAY MORNING. THEN...AN AREA OF LOW PRESSURE STRETCHING
FROM THE SOUTHERN CANADIAN PRAIRIE SOUTH ACROSS THE PLAINS WILL MOVE
NORTHEAST DURING TUESDAY AND WEDNESDAY. WITH HIGH PRESSURE SITUATED
FAR TO THE SOUTH THROUGH SOUTHEAST OF THE LAKE AND LOW PRESSURE FROM
FAR WEST THROUGH NORTHWEST TONIGHT INTO THURSDAY...MODERATE TO FRESH
WINDS WILL PERSIST OUT OF THE SOUTH TO SOUTHWEST.
THIS PERSISTENT FLOW WILL KEEP VERY MOIST AIR ACROSS THE WESTERN
GREAT LAKES REGION. WHILE MOST OF THE FOG HAD DISSIPATED ON NORTHERN
LAKE MICHIGAN...WITH THE MOIST AIR AND COOL LAKE WATER FOG IS
EXPECTED TO REDEVELOP TONIGHT AND BECOME DENSE IN AREAS. THE CURRENT
DENSE FOG ADVISORY FOR NORTHERN LAKE MICHIGAN WILL LIKELY NEED TO BE
EXTENDED INTO TUESDAY AND POSSIBLY WEDNESDAY AS THERE WILL BE NO
CHANGE IN AIRMASS UNTIL A COLD FRONT PUSHES ACROSS THE LAKE DURING
LATER WEDNESDAY AND WEDNESDAY NIGHT...SHIFTING WINDS TO OUT OF THE
WEST. A SECONDARY COLD FRONT WILL MOVE ACROSS THE LAKE AND SHIFT
WINDS TO OUT OF THE NORTHWEST DURING LATER THURSDAY AND THURSDAY
NIGHT.
TRS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565
UNTIL 7 AM MONDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS TOPEKA KS
406 AM CDT MON JUN 24 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 352 AM CDT MON JUN 24 2013
ANOTHER DIFFICULT FORECAST AS MESOSCALE FEATURES CONTINUE TO DEFINE
CONVECTIVE POTENTIAL...AND ARE DIFFICULT TO FORECAST MORE THAN A FEW
HOURS OUT. FOR TODAY...SOUNDINGS SUGGEST WAVE LIFTING OUT OF
OK/CTRL KS MAY SATURATE MID LEVELS ENOUGH TO SUPPORT SOME ISOLATED
CONVECTION THIS MORNING...AND WILL LEAVE AN ISOLATED POP TO REFLECT
THIS. HRRR MODEL...WHICH HAS PERFORMED WELL IN THE MORNING RUNS THIS
WEEK...DEPICTS CONVECTIVE COMPLEX OVER SC NEBRASKA SLIDING SLIGHTLY
TO THE SE AND BACK-BUILD INTO OUR FORECAST AREA LATER THIS
MORNING. FRONTAL BOUNDARY HAS SHIFTED FARTHER NORTHWARD AND SUSPECT
COMPLEX WILL STAY NORTH OF THE FA. ALSO SHOULD CONSIDER OUTFLOW
MOVING SE OUT OF IOWA CONVECTION AND WHERE THAT MAY END UP ON THE
KS/MO BORDER THIS AFTERNOON. AT THIS TIME LESS CINH AND BETTER
DYNAMICS COME TOGETHER NORTH OF THE AREA. HAVE STARTED WITH A SILENT
POP IN THE NE COUNTIES AND WILL MONITOR FOR DEVELOPMENT. BREEZY
SOUTHERLY WINDS WILL BE NEAR BUT GENERALLY BELOW WIND ADVISORY
CRITERIA AND WILL HOLD OFF FOR NOW. HIGHS TODAY IN THE 90S FOLLOWED
BY WARM OVERNIGHT LOWS IN THE MIDDLE 70S. WITH ANOTHER COMPLEX
MOVING NORTH OF THE FORECAST AREA LATE MONDAY INTO EARLY
TUESDAY...WILL CARRY A SLIGHT CHANCE POP ACROSS THE FAR NORTHERN
COUNTIES AS MAY SEE SOME LATE NIGHT COLD POOL LLJ INTERACTION. 67
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 352 AM CDT MON JUN 24 2013
MID RANGE AND EXTENDED FORECAST (TUESDAY THROUGH SUNDAY)...
WARM...MUGGY...AND DRY CONDITIONS EXPECTED TO PERSIST THROUGH MOST OF
THE MID RANGE AND EXTENDED PERIOD. FOR TUESDAY AND WEDNESDAY THE MID
LEVEL RIDGE GETS SOMEWHAT FLATTENED OUT AND DEAMPLIFIED AS THE HIGH
PRESSURE EXPANDS ACROSS THE SOUTHERN PLAINS. EVENTUALLY...BY MID
WEEK THE RIDGE WILL BECOME CENTERED OVER THE FOUR CORNERS REGION OF
THE US...AND WILL BECOME MOVE AMPLIFIED AS THE WEEK PROGRESSES. WITH
THE EASTERN EDGE OF THE HIGH PRESSURE DOME IN THE VICINITY OF
NORTHEAST KANSAS EXPECT SOME MID LEVEL NWLY FLOW TO REMAIN OVER THE
FORECAST AREA...WHICH WILL BRING THE POTENTIAL FOR MCS DEVELOPMENT
WITHIN THE FLOW. FOR NOW WILL KEEP A MOSTLY DRY FORECAST THROUGH THE
EXTENDED PERIOD...WITH THE LONE EXCEPTION OF THURSDAY NIGHT WHERE
THE ECMWF AND GFS AGREE ON THUNDERSTORMS DEVELOPING ALONG THE
PERIPHERY OF THE RIDGE AND DROPPING SOUTH/SOUTHEASTWARD OUT OF SE
NEBRASKA INTO NE KANSAS. GIVEN THE LACK OF ANY STRONG SIGNAL OF
OBVIOUS LIFTING MECHANISMS WILL ONLY GO WITH A SLIGHT CHANCE FOR
SHOWERS AND THUNDERSTORMS FOR THAT PERIOD. OTHERWISE...EXPECT A
RATHER WARM AND MUGGY PERIOD FOR TUES THROUGH THURS AS DAY TIME
HIGHS WILL GENERALLY REACH THE MID TO UPPER 90S...WITH HEAT INDEX
VALUES RANGING BETWEEN 100 AND 105 ACROSS MOST OF THE FORECAST AREA.
TEMPERATURES WILL COOL OFF A BIT FOR THE END OF THE WORK WEEK
THROUGH THE WEEKEND...AS A SURFACE HIGH BRINGS COOLER AIR INTO
NORTHEAST KANSAS. EXPECT TEMPS FOR FRIDAY THROUGH MONDAY TO BE IN
THE UPPER 80S TO PERHAPS THE MID 90S.
JL
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1101 PM CDT SUN JUN 23 2013
VFR IS THE PREVAILING CATEGORY AT KTOP/KFOE/KMHK AS SOUTH
SOUTHEAST WINDS REMAIN STEADY AROUND 10 KTS. CONVECTION FORMING
OVER FAR EASTERN COLORADO MAY ORGANIZE INTO A THUNDERSTORM COMPLEX
AND ENTER THE AREA AFT 11Z. INSERTED A VCTS ATTM AS EXACT TIMING
OF THE TSRA IS STILL UNCERTAIN. GUSTS INCREASE UP TO 30 KTS AFT
14Z MONDAY.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CRAVEN
LONG TERM...LEIGHTON
AVIATION...BOWEN
AREA FORECAST DISCUSSION
NWS CARIBOU ME
535 AM EDT MON JUN 24 2013
.SYNOPSIS...
UNSETTLED CONDITIONS WITH SCATTERED SHOWERS AND THUNDERSTORMS WILL
PERSIST THROUGH MID WEEK.&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE 0530L: DECAYING MCS HAS REACHED OUR FAR WRN ZONES ATTM.
THIS A LITTLE FASTER THAN ERLYR EXPECTED SO HAVE ADJUSTED POPS FOR
CURRENT AND EXPECTED TRENDS THRU THE AM HRS. REMAINDER OF THE FCST UNCHANGED...
DECAYING MCS OVR SRN QUEBEC ATTM ABOUT TO ENTER FAR WRN MAINE...
OTHERWISE...PARTLY TO MOSTLY CLOUDY SKIES ACROSS THE FA ATTM W/
SOME FOG ACROSS THE N. NOT MUCH CHANGE IN THE OVERALL PTRN ACROSS
OUR AREA LAST 24 HRS AT LEAST IN THE UPPER LEVELS OF THE ATMOS AS
BRISK WNW FLOW ALOFT PERSISTS W/ OCNL DISTURBANCES EMBEDDED IN
THIS FLOW. IN THE LOWER LEVELS - A VRY WARM AND HUMID SWRLY FLOW
IS NOW IN PLACE ACROSS THE ENTIRE REGION W/ TDS GENERALLY IN THE
LOWER TO MID 60S. THE DECAYING MCS IS SHOWN BY THE SHORTER TERM
MODELS SUCH AS THE RUC TO CONT TO MV ESEWRD AND HOLD TOGETHER ENUF
TO HAVE SOME IMPACT ON OUR WRN ZNS ERLY TDY THEN ACROSS OUR S
CENTRAL ZNS THRU THE AM HRS AND POPS ACROSS THESE AREAS WILL
REFLECT THIS. OTHERWISE...ANOTHER UPPER DISTURBANCE IS FCST TO
SLIDE ESEWRD ACROSS THE FA LATER TDY AND PROVIDE ANOTHER UPTICK IN
SHOWERS/TSTMS.
UNLIKE SUN...WHERE MOST ACTION WAS S OF THE AREA - APPEARS TDY
THAT THINGS HAVE SHIFTED A LITTLE FURTHER N W/ THE INTRUSION OF
THE WARMER AND MORE HUMID AIR. AS A RESULT...WILL CARRY MAINLY CHC
POPS ACROSS THE REMAINDER OF THE FA TDY INTO THIS EVE W/ ACTIVITY
EXPECTED TO AGAIN WEAKEN/DISSIPATE LATER THIS EVE AS THIS UPPER
DISTURBANCE MVS AWAY FROM THE REGION. THIS WILL SET THE STAGE FOR
MORE PATCHY FOG W/ THE FOG PROBABLY A LITTLE MORE WDSPRD THAN THIS
AM W/ THE HUMID AIRMASS PERSISTING. TEMPS TDY WILL BE A LITTLE
TRICKY... CLDS AND SHOWERS WILL NO DOUBT HAVE SOME IMPACT AND
PROBABLY KEEP MOST AREAS FROM REACHING FULL POTENTIAL TDY.
STILL...A LITTLE SUNSHINE FROM TIME TO TIME IS EXPECTED AND WILL
GO A LONG WAY IN HEATING THINGS UP SO WILL HANG ONTO HIGHS INTO
THE LOWER 80S N W/ MID TO PSBLY UPPER 80S CENTRAL AND INTERIOR
DOWNEAST...&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
PERIOD WILL BEGIN WITH A SURFACE HIGH SETUP IN THE ATLANTIC AND
BOUNDARY DRAPED JUST TO THE NORTH OF THE REGION. THE SURFACE HIGH
WILL CONTINUE TO PUMP WARM AND MOIST AIR INTO THE REGION. GUIDANCE
IS IN FAIR AGREEMENT WITH THE BOUNDARY AND SURFACE LOW BEGINNING
TO DROP SOUTH THROUGH THE DAY ON TUESDAY. THIS COMBINED WITH
BETTER UPPER LEVEL DYNAMICS WITH THE REGION LOCATED IN THE
FAVORABLE RIGHT ENTRANCE REGION OF UPPER LEVEL JET ENHANCING
DIVERGENCE ALOFT. ALSO WITH WARM AND MOIST UNSTABLE AIR IN PLACE
CAPE VALUES WILL BE GENERALLY BETWEEN 500 TO 1500 J/KG. THESE
DYNAMICS WILL MAKE IT POSSIBLE TO HAVE SOME MORE ENHANCED
THUNDERSTORM ACTIVITY TUESDAY AFTERNOON AND EVENING. RIGHT NOW
THINKING IS THERE WILL BE THE POTENTIAL FOR SMALL HAIL AND GUSTY
WINDS BUT THIS MAY NEED TO BE ENHANCED FURTHER IF DYNAMICS
CONTINUE TO COME TOGETHER. BEST CHANCES STILL LOOK TO BE ACROSS
THE NORTHERN AND CENTRAL PORTIONS OF THE REGION WHERE BEST
SUPPORTING DYNAMICS ARE PRESENT.
THERE IS SOME MODEL DIVERGENCE FOR WEDNESDAY WITH THE MOST OF
GUIDANCE WANTING TO KEEP THE LOW PRESSURE ACROSS THE REGION WHILE
THE 23/12Z ECMWF WANTS TO KEEP IT DRIER. RIGHT NOW WILL KEEP
DECENT CONSISTENCY WITH PREVIOUS FORECAST WITH MORE SHOWERY TYPE
ACTIVITY. TEMPERATURES FOR WEDNESDAY LOOK TO BE COOLER ALTHOUGH
THIS WILL BE HIGHLY DEPENDENT ON CLOUD COVER.&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
THE GUIDANCE IS STILL A BIT DIVERGENT IN THE BEGINNING OF THE LONG
TERM PERIOD. THE 24/00Z GFS/GEM WANTS TO HOLD ON TO THE BOUNDARY
AND SURFACE LOW A BIT LONGER THAN THE 23/12Z ECMWF FOR WEDNESDAY
NIGHT. THEN WE WILL SEE ANOTHER STRONG UPPER LEVEL DISTURBANCE
ACROSS THE GREAT LAKES CONTINUE TO PROGRESS EAST. ALL THE LONG
RANGE GUIDANCE INDICATES THIS MOVING EAST BUT WITH SLIGHT DIFFERENCES
IN TIMING. GENERALLY IT LOOKS LIKE THIS SYSTEM WILL BEGIN
PROGRESSING INTO THE REGION THURSDAY AFTERNOON. RIGHT NOW THE
GUIDANCE ALSO WANTS INDICATE THIS UPPER LEVEL LOW BECOMING QUASI-
STATIONARY GENERALLY ACROSS THE GREAT LAKES AND OHIO VALLEY. THIS
WOULD KEEP THE REGION IN A ACTIVE PATTERN THROUGH MUCH OF THE LONG
TERM PERIOD. THIS QUASI-STATIONARY TROUGH SETUP IS ALSO GENERALLY
SUPPORTED BY THE 23/12Z GFS/ECMWF RESPECTIVE ENSEMBLE MEAN. HIGH
AND LOW TEMPERATURES FOR THE PERIOD WILL GENERALLY BE NEAR NORMAL.
&&
.AVIATION /10Z MONDAY THROUGH FRIDAY/...
NEAR TERM: VRBL CONDS ACROSS THE AREA THIS AM W/ SOME IFR IN FOG
ACROSS THE N TO VFR CONDS ACROSS THE S. EXPECT FOG TO DISSIPATE
ERLY THIS AM W/ PREDOM VFR CONDS TDY EXPECT OCNL MVFR TO BRIEF IFR
PSBL IN ANY SHOWERS/TSTMS. FOG WILL AGAIN BE A THREAT TNGT ALONG
W/ A CONTD CHC OF SHOWERS AND PSBL THUNDER...
SHORT TERM: MOST SITES LOOK TO STAY VFR THROUGH THE PERIOD WITH
THE EXCEPTION OF THOSE SITES THAT RECEIVE SHOWER AND THUNDERSTORM
ACTIVITY. THIS WILL BE MORE LIKELY FOR THE NORTHERN SITES.
&&
.MARINE...
NEAR TERM: WINDS/SEAS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT
ADVISORY LEVELS THRU TONIGHT. VISIBILITIES COULD BE REDUCED IN PATCHY
FOG TODAY AND IN MORE WDSPRD AREAS OF FOG TNGT.
SHORT TERM: MARINE: NO HEADLINES EXPECTED AT THIS TIME WITH SEAS
GENERALLY STAYING 2 TO 4 FT AND WINDS 10 TO 15 KT. VISIBILITIES
COULD BE REDUCED WITH SHOWERS.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...KHW
SHORT TERM...JORDAN
LONG TERM...JORDAN
AVIATION...KHW/JORDAN
MARINE...KHW/JORDAN
AREA FORECAST DISCUSSION
NWS GRAY ME
534 AM EDT MON JUN 24 2013
.SYNOPSIS...
WARM AND MOIST AIR CONTINUES TO POOL ALONG AND SOUTH OF A
STATIONARY FRONT SITUATED TO OUR NORTH. SCATTERED SHOWERS AND
THUNDERSTORMS ARE EXPECTED EACH DAY THROUGH THE WEEK AS SEVERAL
DISTURBANCES CROSS THE REGION. A LARGE UPPER LEVEL TROUGH WILL
APPROACH FROM THE WEST LATE IN THE WEEK. THIS WILL ALLOW FOR
COOLER TEMPERATURES...BUT INCREASE THE CHANCE FOR SHOWERS ACROSS
THE REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE...
UPDATE EARLY THIS MORNING IF FOR THE CHANCES OF PRECIPTATION BEING
LIMITED THIS MORNING...WITH THE EXCEPTION OF THE NORTH AND
MOUNTAINS WHERE OLD MCS CONTINUES TO DETEORATE AND MOVE EAST
ACROSS MAINE. LATEST HRRR MODEL IS PICKING UP ON THIS SYSTEM WELL
THIS MORNING. CONVECTIVE INITIATION THIS AFTERNOON APPEARS TO BE
AROUND 18Z-19Z OVER VERMONT. CELLS WILL ENTER NEW HAMPSHIRE BY
AROUND 20Z.
PREV DISC...
THE REMAINS OF AN MCS WILL CROSS NORTHERN SECTIONS EARLY THIS
MORNING...AS IT CONTINUES TO WEAKEN AS IT MOVES EAST. A DEVELOPING
WESTERLY FLOW ALOFT WILL ALLOW 850 MB TEMPERATURES TO CLIMB TO AOA
+16C DURING THE AFTERNOON HOURS. WITH AMPLE MIXING...WE SHOULD
EXPECT SOME LOWER 90S OVER SOUTHERN/CENTRAL NH AND ADJACENT
SECTIONS OF WESTERN MAINE. THERE WILL BE A SURFACE TROUGH SITUATED
NEAR AND ALONG THE COASTLINE...SO ONSHORE WINDS WILL LIKELY KEEP
THINGS COOLER OVER THE MIDCOAST REGION.
CAPES SOAR THIS AFTERNOON INTO THE 1500 J/KG RANGE OVER SOUTHERN
MAINE AND POSSIBLY SOUTHERN NEW HAMPSHIRE DURING THE AFTERNOON
HOURS TODAY AS A SHORT WAVE APPROACHES FROM THE WEST. LIS DROP
SIGNIFICANTLY AS WELL. WE ARE NOT OUTLOOKED BY SPC TODAY...HOWEVER
FEEL COMPELLED TO AT LEAST MENTIONED GUSTY WINDS AND SMALL HAIL IN
THIS AREA.
PRECIPITABLE WATER VALUES WILL BE VERY HIGH TODAY...CLOSE TO 1.75
INCHES. WESTERLY FLOW SHOULD ALLOW FOR QUICK PROGRESSION OF
STORMS. NEVERTHELESS...ANY TRAINING ECHOES WILL NEED TO BE
MONITORED CLOSELY FOR THE THREAT OF HEAVY RAINFALL.
USED A BLEND OF MAV/MET MOS FOR DAYTIME MAX TEMPERATURES...WHICH
PLACES MANY AREAS IN THE LOWER 90S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
PATCHY FOG WILL REDEVELOP TONIGHT...ESPECIALLY IN THE VALLEY
LOCATIONS. THEREAFTER...SHOWERS AND THUNDERSTORMS WILL DEVELOP
DURING THE EARLY AFTERNOON HOURS ON TUESDAY AS VORT MAX APPROACHES
FROM THE NORTH. EXPECT SEVERAL STORMS TO PRODUCE DAMAGING WIND
GUSTS AS THE PRIMARY THREAT FOR SEVERE WEATHER AS THE WIND MAX
CROSSES THE REGION...BUT WE CAN`T RULE OUT THE POSSIBILITY OF LARGE
HAIL AS WELL. WILL HIGHLIGHT THIS IN THE HWO.
EXPECT MANY COMMUNITIES TO TOP OUT AT OR ABOVE 90 DEGREES ONCE
AGAIN OVER SOUTHER/CENTRAL NEW HAMPSHIRE AND WESTERN MAINE.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
THRU THE OUTLOOK PERIOD THE EVOLUTION OF A LONG WAVE TROF WILL
BECOME ESTABLISHED OVER THE ERN GT LAKES AND EXTEND S INTO THE
OHIO VALLEY. THIS L/WV TROF WILL BECOME THE MAIN WX PRODUCER FOR
THE FCST PERIOD OF WED-SUN. THE DEVELOPING EASTERN L/WV TROF WILL
MEAN A CONTINUED MOIST AND UNSTBL SSWLY FLOW AT THE SFC/ALOFT THRU
THE WEEK. SHWRS/TSTMS ARE EXPECTED THROUGHOUT THE WEEK AND INTO
THE WEEKEND. TEMPS WILL BE COOLER THROUGH THE WEEK DUE TO PLENTY
OF CLOUDS AND THE MOIST SLY FLOW. HIGH TEMPS WILL BE MOSTLY IN THE
70S BUT DEWPOINTS WILL REMAIN HIGH SO IT WILL BE MUGGY AS WELL.
USED A BLEND OF THE MAV/MET GUID FOR 4TH/5TH PERIODS AND THEN THE
ADJUSTED MEX TEMPS FOR DAYS 4-7.
&&
.AVIATION /10Z MONDAY THROUGH FRIDAY/...
SHORT TERM...
MOISTURE TRAPPED UNDER AN INVERSION WILL KEEP PERIODS OF LIFR AND
VLIFR CEILINGS IN THE TERMINAL FORECASTS EARLY THIS MORNING. WEST
WINDS TODAY MAY GUST INTO THE LOWER 20S. WINDS AND THE POTENTIAL
FOR HAIL IS POSSIBLE OVER SOUTHERN AREAS OF MAINE THIS AFTERNOON
AND OVER ALL AREAS ON TUESDAY.
LONG TERM...
VARIABLE CONDS EXPECTED THRU THE OUTLOOK PERIOD. VFR CONDS ARE
EXPECTED AT TIMES BUT WILL LOWER TO MVFR TO IFR IN SCT SHWRS/TSTMS
THROUGHOUT THE MIDDLE TO END OF THE WEEK.
&&
.MARINE...
SHORT TERM...
WINDS MAY BECOME GUSTY OVER THE OUTER WATERS TODAY...BUT MOST
LIKELY REMAINING BELOW SCA CRITERIA. SIMILAR CONDITIONS WILL
FOLLOW ON TUESDAY.
LONG TERM...
WINDS/SEAS WILL REMAIN BLO SCA CONDS THRU THURSDAY BUT MAY
INCREASE TO SCA CRITERIA ON FRI DUE TO AN INCREASING SLY PRES
GRADIENT ALLOWING WINDS AND SEAS TO INCREASE.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CARIBOU ME
407 AM EDT MON JUN 24 2013
.SYNOPSIS...
UNSETTLED CONDITIONS WITH SCATTERED SHOWERS AND THUNDERSTORMS WILL
PERSIST THROUGH MID WEEK.&&
.NEAR TERM /THROUGH TONIGHT/...
DECAYING MCS OVR SRN QUEBEC ATTM ABOUT TO ENTER FAR WRN MAINE...
OTHERWISE...PARTLY TO MOSTLY CLOUDY SKIES ACROSS THE FA ATTM W/
SOME FOG ACROSS THE N. NOT MUCH CHANGE IN THE OVERALL PTRN ACROSS
OUR AREA LAST 24 HRS AT LEAST IN THE UPPER LEVELS OF THE ATMOS AS
BRISK WNW FLOW ALOFT PERSISTS W/ OCNL DISTURBANCES EMBEDDED IN
THIS FLOW. IN THE LOWER LEVELS - A VRY WARM AND HUMID SWRLY FLOW
IS NOW IN PLACE ACROSS THE ENTIRE REGION W/ TDS GENERALLY IN THE
LOWER TO MID 60S. THE DECAYING MCS IS SHOWN BY THE SHORTER TERM
MODELS SUCH AS THE RUC TO CONT TO MV ESEWRD AND HOLD TOGETHER ENUF
TO HAVE SOME IMPACT ON OUR WRN ZNS ERLY TDY THEN ACROSS OUR S
CENTRAL ZNS THRU THE AM HRS AND POPS ACROSS THESE AREAS WILL
REFLECT THIS. OTHERWISE...ANOTHER UPPER DISTURBANCE IS FCST TO
SLIDE ESEWRD ACROSS THE FA LATER TDY AND PROVIDE ANOTHER UPTICK IN
SHOWERS/TSTMS.
UNLIKE SUN...WHERE MOST ACTION WAS S OF THE AREA - APPEARS TDY
THAT THINGS HAVE SHIFTED A LITTLE FURTHER N W/ THE INTRUSION OF
THE WARMER AND MORE HUMID AIR. AS A RESULT...WILL CARRY MAINLY CHC
POPS ACROSS THE REMAINDER OF THE FA TDY INTO THIS EVE W/ ACTIVITY
EXPECTED TO AGAIN WEAKEN/DISSIPATE LATER THIS EVE AS THIS UPPER
DISTURBANCE MVS AWAY FROM THE REGION. THIS WILL SET THE STAGE FOR
MORE PATCHY FOG W/ THE FOG PROBABLY A LITTLE MORE WDSPRD THAN THIS
AM W/ THE HUMID AIRMASS PERSISTING. TEMPS TDY WILL BE A LITTLE
TRICKY... CLDS AND SHOWERS WILL NO DOUBT HAVE SOME IMPACT AND
PROBABLY KEEP MOST AREAS FROM REACHING FULL POTENTIAL TDY.
STILL...A LITTLE SUNSHINE FROM TIME TO TIME IS EXPECTED AND WILL
GO A LONG WAY IN HEATING THINGS UP SO WILL HANG ONTO HIGHS INTO
THE LOWER 80S N W/ MID TO PSBLY UPPER 80S CENTRAL AND INTERIOR
DOWNEAST...&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
PERIOD WILL BEGIN WITH A SURFACE HIGH SETUP IN THE ATLANTIC AND
BOUNDARY DRAPED JUST TO THE NORTH OF THE REGION. THE SURFACE HIGH
WILL CONTINUE TO PUMP WARM AND MOIST AIR INTO THE REGION. GUIDANCE
IS IN FAIR AGREEMENT WITH THE BOUNDARY AND SURFACE LOW BEGINNING TO
DROP SOUTH THROUGH THE DAY ON TUESDAY. THIS COMBINED WITH BETTER
UPPER LEVEL DYNAMICS WITH THE REGION LOCATED IN THE FAVORABLE
RIGHT ENTRANCE REGION OF UPPER LEVEL JET ENHANCING DIVERGENCE
ALOFT. ALSO WITH WARM AND MOIST UNSTABLE AIR IN PLACE CAPE VALUES
WILL BE GENERALLY BETWEEN 500 TO 1500 J/KG. THESE DYNAMICS WILL
MAKE IT POSSIBLE TO HAVE SOME MORE ENHANCED THUNDERSTORM ACTIVITY
TUESDAY AFTERNOON AND EVENING. RIGHT NOW THINKING IS THERE WILL BE
THE POTENTIAL FOR SMALL HAIL AND GUSTY WINDS BUT THIS MAY NEED TO
BE ENHANCED FURTHER IF DYNAMICS CONTINUE TO COME TOGETHER. BEST
CHANCES STILL LOOK TO BE ACROSS THE NORTHERN AND CENTRAL PORTIONS
OF THE REGION WHERE BEST SUPPORTING DYNAMICS ARE PRESENT.
THERE IS SOME MODEL DIVERGENCE FOR WEDNESDAY WITH THE MOST OF
GUIDANCE WANTING TO KEEP THE LOW PRESSURE ACROSS THE REGION WHILE
THE 23/12Z ECMWF WANTS TO KEEP IT DRIER. RIGHT NOW WILL KEEP
DECENT CONSISTENCY WITH PREVIOUS FORECAST WITH MORE SHOWERY TYPE
ACTIVITY. TEMPERATURES FOR WEDNESDAY LOOK TO BE COOLER ALTHOUGH
THIS WILL BE HIGHLY DEPENDENT ON CLOUD COVER.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
THE GUIDANCE IS STILL A BIT DIVERGENT IN THE BEGINNING OF THE LONG
TERM PERIOD. THE 24/00Z GFS/GEM WANTS TO HOLD ON TO THE BOUNDARY
AND SURFACE LOW A BIT LONGER THAN THE 23/12Z ECMWF FOR WEDNESDAY
NIGHT. THEN WE WILL SEE ANOTHER STRONG UPPER LEVEL DISTURBANCE
ACROSS THE GREAT LAKES CONTINUE TO PROGRESS EAST. ALL THE LONG
RANGE GUIDANCE INDICATES THIS MOVING EAST BUT WITH SLIGHT DIFFERENCES
IN TIMING. GENERALLY IT LOOKS LIKE THIS SYSTEM WILL BEGIN
PROGRESSING INTO THE REGION THURSDAY AFTERNOON. RIGHT NOW THE
GUIDANCE ALSO WANTS INDICATE THIS UPPER LEVEL LOW BECOMING QUASI-
STATIONARY GENERALLY ACROSS THE GREAT LAKES AND OHIO VALLEY. THIS
WOULD KEEP THE REGION IN A ACTIVE PATTERN THROUGH MUCH OF THE LONG
TERM PERIOD. THIS QUASI-STATIONARY TROUGH SETUP IS ALSO GENERALLY
SUPPORTED BY THE 23/12Z GFS/ECMWF RESPECTIVE ENSEMBLE MEAN. HIGH
AND LOW TEMPERATURES FOR THE PERIOD WILL GENERALLY BE NEAR NORMAL.
&&
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
NEAR TERM: VRBL CONDS ACROSS THE AREA THIS AM W/ SOME IFR IN FOG
ACROSS THE N TO VFR CONDS ACROSS THE S. EXPECT FOG TO DISSIPATE
ERLY THIS AM W/ PREDOM VFR CONDS TDY EXPECT OCNL MVFR TO BRIEF IFR
PSBL IN ANY SHOWERS/TSTMS. FOG WILL AGAIN BE A THREAT TNGT ALONG
W/ A CONTD CHC OF SHOWERS AND PSBL THUNDER...
SHORT TERM: MOST SITES LOOK TO STAY VFR THROUGH THE PERIOD WITH
THE EXCEPTION OF THOSE SITES THAT RECEIVE SHOWER AND THUNDERSTORM
ACTIVITY. THIS WILL BE MORE LIKELY FOR THE NORTHERN SITES.
&&
.MARINE...
NEAR TERM: WINDS/SEAS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT
ADVISORY LEVELS THRU TONIGHT. VISIBILITIES COULD BE REDUCED IN PATCHY
FOG TODAY AND IN MORE WDSPRD AREAS OF FOG TNGT.
SHORT TERM: MARINE: NO HEADLINES EXPECTED AT THIS TIME WITH SEAS
GENERALLY STAYING 2 TO 4 FT AND WINDS 10 TO 15 KT. VISIBILITIES
COULD BE REDUCED WITH SHOWERS.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...KHW
SHORT TERM...JORDAN
LONG TERM...JORDAN
AVIATION...KHW/JORDAN
MARINE...KHW/JORDAN
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
120 AM EDT MON JUN 24 2013
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 418 PM EDT SUN JUN 23 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL LOW OVER SE
SASK INTO SRN MANITOBA WITH A SHORTWAVE TROUGH EXTENDING INTO ERN ND
AND NW MN. AT THE SFC...A 999MB SFC LOW WAS LOCATED OVER THE NW CORNER
OF MN WITH A WARM FRONT EXTENDING INTO SRN LAKE SUPERIOR. CLEARING
AND AFTERNOON HEATING HAS PUSHED TEMPS INTO THE LOWER 80S OVER WRN
UPPER MI RESULTING IN MLCAPE VALUES TO AROUND 1500 J/KG. SCT
SHRA/TSRA WERE DEVELOPING OVER WRN LAKE SUPERIOR INTO NW UPPER MI
CLOSEST TO THE FORCING ASSOCIATED WITH THE ND/MN SHRTWV.
EXPECT THAT SCT SHRA/SHRA WILL CONTINUE TO DEVELOP BACK THROUGH WRN
UPPER MI LATE THIS AFTERNOON AS A WEAK TROUGH MOVES INTO THE
AREA...PER HIGH RES MODELS. INSTABILITY ALONG WITH 30-35 KT 0-6KM
SHEAR AND 20-25 KT 0-1KM SHEAR COULD SUPPORT AT LEAST ISOLD
STRONG/SEVERE STORMS...WITH STRONG WIND GUSTS AS THE MAIN HAZARD
GIVEN DCAPE VALUES INTO THE 500-1000 J/KG RANGE. EXPECT THAT THE
SHRA/TSRA WILL SPREAD INTO CNTRL UPPER MI BY 21Z-23Z AND THEN
DISSIPATE AND WEAKEN BY LATE EVENING AS THE SHRA/TSRA MOVE TOWARD
THE ERN CWA...AWAY FROM THE THE STRONGER INSTABILITY AND THE SHRTWV
FORCING.
AS THE SHORTWAVE AND LOW MOVE INTO NRN ONTARIO THE DRY SLOT AND
STRONG MID LEVEL DRYING WILL SPREAD ACROSS THE REGION LATE TONIGHT
INTO MONDAY. THIS WILL HELP MINIMIZE CHANCES FOR ADDITIONAL
CONVECTION. WITH SUNSHINE AND 850 MB TEMPS STILL AROUND 15C...TEMPS
WILL AGAIN CLIMB INTO THE LOWER 80S.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 418 PM EDT SUN JUN 23 2013
GENERAL AGREEMENT IN OVERALL LOOK OF LARGER SCALE PATTERN INTO NEXT
WEEKEND THOUGH DETAILS AND SPECIFICS REMAIN UNCERTAIN. TO START ON
MONDAY EVENING...FAIRLY STRONG SHORTWAVE TROUGH WILL BE HEADING EAST
ACROSS NORTHERN ONTARIO LEAVING RIDGING IN ITS WAKE OVER NORTHERN
PLAINS. SFC FRONT AND POOL OF SFC-H85 MOISTURE ALONG THE BOUNDARY
DRIVES SOUTH OF CWA BY LATE MONDAY EVENING RESULTING IN GENERALLY
QUIET AND LESS HUMID WEATHER INTO MUCH OF TUESDAY. GFS AND ECMWF
AGREE HERE...WHILE THE GEM-NH AND THE UKMET DO NOT PUSH WARM FRONT
FAR ENOUGH SOUTH TO KEEP CHANCES OF SHRA/TSRA OUT OF CWA. WILL LEAN
ON THE MORE CONSISTENT ECMWF IDEA WHICH IS SUPPORTED BY WPC HAND
DRAWN SFC MAP.
WITH WARM FRONT AND EDGE OF SFC BASED-MUCAPE MOST LIKELY STILL SOUTH
BY TUESDAY AFTN...WONDER IF MOST AREAS STAY DRY THROUGH TUESDAY. ANY
SHRA/TSRA THAT FORM MONDAY NIGHT INTO TUESDAY MORNING SHOULD STAY
SOUTH OF CWA PER H85-H3 THICKNESSES AND FORWARD PROPAGATING CORFIDI
VECTORS AND EVEN THE MEAN LAYER WIND. INTO TUESDAY NIGHT...ECMWF AND
GFS STILL HAVE SHORTWAVE CRASHING THROUGH TOP EDGE OF LARGER SCALE
RIDGING. WAVE MAY AID IN BRINGING AT LEAST H85 FRONT FAR ENOUGH
NORTH THAT SOUTHERN TIER COULD BE AFFECTED BY SHRA/TSRA TUESDAY
NIGHT AND MUCH OF THE CWA COULD SEE SHRA/TSRA ON WEDNESDAY. GFS
STRONGER WITH THIS WAVE SO MUCH THAT IT PUSHES SFC WARM FRONT INTO
CWA ON WEDNESDAY. PV ANAMOLY THAT GFS CARRIES IN HERE ON WEDNESDAY
TRACKS BACK TO SOUTH EDGE OF STRONG UPR LOW OVER THE ALLUTIANS THIS
MORNING. WAVE LOOKS PRETTY VIGOROUS ON WV LOOP. ECMWF HAS BETTER
TRACK RECORD IN THE EXTENDED...BUT WILL BLEND SOME OF THE GFS IDEA
IN AS WELL SINCE IT SEEMS TO HAVE SOME MERIT.
TROUGH AND HIGHER SFC-H85 DWPNTS PUSH THROUGH AREA WEDNESDAY EVENING
AND COOLER AIR ARRIVES LATER ON THURSDAY. GFS QUICKER AND STRONGER
AS WELL AS FARTHER SOUTH WITH SHORTWAVE TROUGH DIGGING ACROSS UPR
LAKES ON THURSDAY WHILE THE ECMWF SHOWS MORE SEPARATION BTWN THE
WAVE ON WEDNESDAY AND THAT STRONGER TROUGHING. GFS HAS TENDENCY TO
BRING SYSTEMS IN TOO QUICKLY AND ITS SOLUTION VERIFYING AT 12Z
THURSDAY HAS SHOWN TOO MUCH INCONSISTENCY TO PUT MUCH STOCK IN IT AT
THIS POINT. ECMWF HAS TRENDED A BIT SHAPRER WITH TROUGH BUT OVERALL
HAS BEEN MUCH MORE CONSISTENT THAN GFS. WILL PREFER THAT IDEA FOR
NOW. RESULT WILL BE SCT SHRA/TSRA...MAYBE EVEN NMRS FOR A TIME
WEDNESDAY OR WEDNESDAY EVENING...THEN DIMINISHING WITH LOSS OF
INSTABILITY AXIS LATER WEDNESDAY NIGHT. POTENTIAL FOR ANOTHER ROUND
OF SCT SHRA/TSRA DURING PEAK HEATING ON THURSDAY AS AIRMASS OVER THE
REGION IS STILL A BIT UNSTABLE /MLCAPES UP TO 1000 J/KG/ WHILE WNW
FLOW ALOFT INCREASES ON SOUTH EDGE OF UPPER TROUGH. LIGHT AND
VARIABLE SFC WINDS COULD RESULT IN LAKE BREEZE CONVERGENCE AS WELL.
ALWAYS HAVE TO WATCH OUT FOR WNW-NW FLOW ALOFT AS THAT PATTERN WITH
SUFFICIENT INSTABILITY IS ONE THAT CAN RESULT IN AT LEAST SOME
CHANCE OF SEVERE WEATHER.
UPPER TROUGH DOMINATES ON FRIDAY WITH A BIT COOLER AND UNSETTLED
WEATHER. NO TSRA EXPECTED ON FRIDAY AS COOLER TEMPS ALOFT/STEEPER
LAPSE RATES SETUP FROM NORTHERN ONTARIO INTO THE LOWER GREAT LAKES.
COULD BE SHRA AT TIMES THOUGH AS SMALLER SCALE SHORTWAVES ROTATE
AROUND PRIMARY UPPER TROUGH. FRIDAY NIGHT INTO SATURDAY MAY BE KIND
OF BLUSTERY ALONG LK SUPERIOR AND WITH ONSHORE WINDS SWIM RISK MAY
BE HIGHER TO START THE WEEKEND. SMALL CHANCES OF SHRA MAY LINGER
INTO SATURDAY AS WELL. TEMPS SOME AREAS FRIDAY INTO SATURDAY MAY
END UP MORE THAN 10 DEGREES BELOW NORMAL. HIGH PRESSURE BUILDS IN
FOR LATER IN THE WEEKEND...RESULTING IN TEMPS BOUNCING UP AT LEAST
TOWARD NORMAL. NEXT SHORTWAVE IN WNW FLOW APPEARS LATE IN THE WEEKEND
SO HAVE POPS MOVING BACK IN FOR LATE SUNDAY. NO REAL WARM TEMPERATURES
SEEN NEXT WEEKEND OR EVEN INTO EARLY NEXT WEEK AS TROUGHING ALOFT
OVER EASTERN CANADA AND GREAT LAKES KEEPS WARM AIR RESTRICTED TO
WESTERN AND SOUTHERN PORTIONS OF CONUS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 120 AM EDT MON JUN 24 2013
WITH HUMID AIR MASS IN PLACE AND SOME RAINFALL ACROSS THE AREA
YESTERDAY...MAY SEE SOME FOG OVERNIGHT...REDUCING VIS TO MVFR. GIVEN
STRONGER WINDS JUST ABOVE NOCTURNAL INVERSION THAT WILL INDUCE
SUFFICIENT MECHANICAL MIXING...FOG SHOULDN`T BECOME TOO THICK TO
REDUCE VIS BLO MVFR. OTHERWISE...VFR CONDITIONS SHOULD PREVAIL THRU
THE PERIOD AT KIWD/KCMX/KSAW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 418 PM EDT SUN JUN 23 2013
WINDS SHOULD REMAIN 25 KTS OR LESS THROUGH THE UPCOMING WEEK. MAIN
HAZARD WILL BE SCT THUNDERSTORMS TONIGHT AND FOG. DENSE
FOG ADVISORIES HAVE BEEN EXTENDED THROUGH TONIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 5 AM EDT /4 AM CDT/ EARLY THIS MORNING
FOR LSZ162-263>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...ROLFSON
MARINE...JLB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
ISSUED BY THE NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
115 AM CDT MON JUN 24 2013
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 317 PM CDT SUN JUN 23 2013
MORNING MAP ANALYSIS INDICATES QUASI ZONAL TO SOUTHWESTERLY MID TO
UPPER LEVEL FLOW OVER THE WESTERN HALF OF THE CONUS...WITH A
LONGWAVE RIDGE OVER THE EAST. A COUPLE OF MID LEVEL SHORT WAVES ARE
ALSO NOTED...WITH ONE EXTENDING FROM THE UPPER MISSISSIPPI VALLEY
INTO THE NORTHERN PLAINS...AND THE OTHER OVER THE SOUTHWESTERN
CONUS. MID TO UPPER LEVEL JET ENERGY EXTENDS FROM THE
WEST/SOUTHWESTERN CONUS...EAST/NORTHEAST INTO THE CENTRAL
PLAINS...AND THEN NORTH INTO SOUTH CENTRAL CANADA BEFORE FLOWING
EAST INTO SOUTHEASTERN CANADA AND PORTIONS OF THE NORTHEASTERN
CONUS. MID TO UPPER LEVEL FLOW OVER OUR AREA MAXES OUT AT AROUND
60KTS BETWEEN 300MB AND 200MB PER 12Z SOUNDING DATA FROM KLBF AND
KOAX. WATER VAPOR IMAGERY ALSO SHOWS THE AFOREMENTIONED MID LEVEL
SHORT WAVES...ALONG WITH A PAIR OF CLOSED MID LEVEL LOWS. ONE SUCH
LOW IS LOCATED OVER EASTERN ALBERTA AND WESTERN SASKATCHEWAN...AND
THE OTHER IS OVER THE PACIFIC JUST OFF THE COAST OF THE NORTHWESTERN
CONUS. AT THE SURFACE AN AREA OF LOW BAROMETRIC PRESSURE EXISTS OVER
SOUTHWESTERN KANSAS...WITH A FRONTAL BOUNDARY EXTENDING
NORTHEAST FROM THE LOW INTO NORTH CENTRAL KANSAS AND
SOUTHEASTERN NEBRASKA. THE LOW LEVEL WIND FIELD ACROSS MUCH OF OUR
CWA REMAINS FROM THE NORTHEAST FOR THE MOST PART...BUT LOCATIONS
ACROSS OUR SOUTHEAST SUCH AS KK82...KK61...AND KHJH ARE ALL
OBSERVING A SURFACE WIND FROM THE SOUTHEAST.
GUIDANCE FROM THE NAM...OPERATIONAL GFS...EC...AND SREF-MEAN
SUGGESTS THE LOW LEVEL BAROCLINIC ZONE WILL PERSIST OVER
SOUTHEASTERN PORTIONS OF OUR CWA THIS EVENING INTO TONIGHT BEFORE
SURGING NORTH DURING THE DAY MONDAY. THERE ARE
INDICATIONS...ESPECIALLY FROM HIGHER RESOLUTION MODELS SUCH AS THE
NAM12...OF VERY SUBTLE MID LEVEL PERTURBATIONS MOVING OVERHEAD
WITHIN THE MEAN FLOW THIS AFTERNOON AND THIS EVENING. CONFIDENCE ON
SUCH A FEATURE PROMOTING PRECIPITATION PRODUCTION ACROSS OUR AREA
THIS AFTERNOON AND EVENING REMAINS VERY LOW HOWEVER AND AS A
RESULT...WILL CONTINUE RELEGATING ANY AFTERNOON AND EVENING POPS TO
OUR SOUTH/SOUTHEASTERN CWA...IN CLOSEST PROXIMITY TO THE
AFOREMENTIONED LOW LEVEL BAROCLINIC ZONE AND RESULTANT AXIS OF
ENHANCED LOW LEVEL CONVERGENCE AND LIFT. AS FOR THE TIMING OF
CONVECTIVE INITIATION THIS AFTERNOON AND EVENING...FORECAST PROXIMITY
SOUNDINGS FROM THE NAM...OPERATIONAL GFS...AND RAP ALL SUGGEST A
HEALTHY CAP PERSISTING THROUGH AT LEAST 00Z. GIVEN THIS...ITS HARD
TO BUY INTO QPF FIELDS FROM THE NAM...OPERATIONAL GFS...EC...AND
SREF-MEAN...WHICH ALL SUGGEST WIDESPREAD PRECIPITATION WILL BE REALIZED ACROSS
PORTIONS OF OUR SOUTHEAST BEFORE 00Z THIS EVENING. HRRR SIMULATED
REFLECTIVITY LOOKS MUCH MORE REASONABLE...SUGGESTING VERY ISOLATED
CONVECTION OCCURRING ACROSS OUR SOUTHEAST TOWARDS 00Z. GIVEN ALL
THIS...CONFIDENCE IS VERY LOW THAT MUCH PRECIPITATION WILL BE
REALIZED ACROSS OUR AREA PRIOR TO 00Z...BUT CANNOT COMPLETELY RULE
OUT SUCH A SOLUTION AND WILL MAINTAIN ~20% POPS ACROSS OUR SOUTHEAST
23-00Z. 00Z AND BEYOND...FORECAST PROXIMITY SOUNDINGS SUGGEST THE CAPPING
INVERSION WILL WEAKEN SOMEWHAT THUS MAKING CONVECTION SOMEWHAT MORE
LIKELY...A SOLUTION SUPPORTED BY QPF FIELDS FROM THE
NAM...OPERATIONAL GFS...EC...AND SREF-MEAN...AS WELL AS SIMULATED
REFLECTIVITY FROM THE HRRR. GIVEN THIS...WILL GO AHEAD WITH SLIGHTLY
HIGHER POPS...~%30...00-06Z ACROSS OUR SOUTHEAST. SHOULD
SURFACE-BASED CONVECTION BE REALIZED THIS AFTERNOON AND/OR
EVENING...THEN SEVERE WEATHER WILL LIKELY RESULT WITH DEEP LAYER
MUCAPE VALUES IN THE 2000-4000J/KG WAITING FOR UPDRAFT PRODUCTION
AND 30-35KTS OF DEEP LAYER BULK SHEAR FOR UPDRAFT ENHANCEMENT.
CERTAINLY LARGE HAIL AND MICROBURST-RELATED WIND GUSTS WILL BE A
THREAT...BUT ENHANCED HORIZONTAL VORTICITY IN THE VICINITY OF THE
LOW LEVEL BAROCLINIC ZONE COULD ALSO PROMOTE ISOLATED TORNADIC
ACTIVITY. WILL CONTINUE SUCH WORDING IN THE HWO AS A RESULT.
HEADING INTO THE OVERNIGHT HOURS TONIGHT...THE AXIS OF A ~45KT 850MB
JET STREAK IS EXPECTED TO DEVELOP ACROSS PORTIONS OF WESTERN AND
CENTRAL KANSAS...WITH THE NOSE OF THIS LOW LEVEL JET MOVING INTO
SOUTHERN PORTIONS OF OUR CWA BETWEEN 06Z AND 12Z. SHOULD DEEP
CONVECTION BE ONGOING ALONG THE LOW LEVEL BAROCLINIC ZONE...THEN
INCREASING LOW LEVEL THERMAL ADVECTION ALONG THE AXIS OF THE LOW
LEVEL JET COULD CERTAINLY HELP INCREASE SPATIAL COVERAGE OF SAID
CONVECTIVE ACTIVITY. ALSO...IN ADDITION TO POSSIBLE THUNDERSTORM
ACTIVITY OVER PORTIONS OF OUR CWA THIS AFTERNOON AND
EVENING...THUNDERSTORMS ALSO REMAIN POSSIBLE OVER THE CENTRAL HIGH
PLAINS. SHOULD HIGH PLAINS CONVECTION DEVELOP THIS AFTERNOON/EVENING
AND MOVE EAST TOWARDS OUR AREA TONIGHT...ADDITIONAL SHOWER AND
THUNDERSTORM ACTIVITY COULD BE REALIZED OVER OUR AREA
TONIGHT...ESPECIALLY OUR WEST. THIS IS A SOLUTION SUPPORTED BY THE
NAM...OPERATIONAL GFS...SREF-MEAN...AND HRRR. GIVEN ALL THIS...WENT
AHEAD WITH RELATIVELY HIGHER POPS ACROSS MUCH OF THE CWA STARTING
AROUND 06Z. SEVERE WEATHER COULD CERTAINLY BE POSSIBLE DURING THE
EARLY PART OF THE OVERNIGHT HOURS AS THE MORE ROBUST CONVECTION FROM
EARLIER IN THE EVENING...SHOULD IT DEVELOP...MAINTAINS ITSELF. THAT
BEING SAID...BARRING THE DEVELOPMENT OF AN MCS ACROSS THE
REGION...CONVECTIVE ACTIVITY SHOULD WANE IN INTENSITY AS POTENTIAL
INSTABILITY DECREASES 06Z ONWARD.
THERE COULD SOME LINGERING SHOWER AND THUNDERSTORM ACTIVITY ACROSS
OUR AREA AROUND SUNRISE MONDAY...BUT OTHERWISE MONDAY DURING THE DAY
IS EXPECTED TO REMAIN DRY FOR THE MOST PART AS THE WARM FRONT SURGES
NORTH AND AN OVERALL LACK IN KINEMATIC FORCING OVERTAKES THE AREA.
AT THIS TIME THE ONLY REAL THREAT FOR PRECIPITATION DURING THE DAY
MONDAY APPEARS AS THOUGH IT WILL RESIDE OVER OUR SOUTHWESTERN CWA
DURING THE LATE AFTERNOON AND EVENING HOURS...WHICH IS WHERE AND
WHEN GUIDANCE SUGGESTS AN ADVANCING LOW LEVEL DRY LINE WILL BULGE EAST.
AN AREA OF LOCALLY ENHANCED CONVERGENCE AND LIFT IN THE VICINITY OF
THIS DRY LINE BULGE...WORKING IN CONCERT WITH DIABATIC HEATING...MAY
BE ENOUGH TO INITIALIZE ISOLATED SHOWER AND THUNDERSTORM DEVELOPMENT
AND AS A RESULT...~20% POPS ARE FORECAST 21Z MONDAY THROUGH 00Z
TUESDAY ACROSS OUR SOUTHWEST. SHOULD THUNDERSTORM ACTIVITY BE REALIZED LATE
MONDAY AFTERNOON AND/OR EVENING...THEN DEEP LAYER MUCAPE VALUES OF
2000-3000J/KG...ALONG WITH DEEP LAYER BULK SHEAR VALUES OF
~30KTS...WILL BE AVAILABLE FOR UPDRAFT PRODUCTION AND ENHANCEMENT.
GIVEN THIS...WILL GO AHEAD AND HIGHLIGHT THE THREAT FOR ISOLATED
SEVERE WEATHER ACROSS OUR SOUTHWEST MONDAY AFTERNOON AND EVENING.
FINALLY...INCREASING SOUTHERLY FLOW WILL LIKELY BE OBSERVED MONDAY
AFTERNOON ONCE THE SURFACE WARM FRONT SURGES NORTH. GUIDANCE
SUGGESTS A SUSTAINED WIND OF ~24KTS...WITH HIGHER GUSTS APPROACHING
35KTS...WILL BE REALIZED PRIMARILY ACROSS NORTH CENTRAL KANSAS. AS A
RESULT...WILL CONTINUE MENTIONING SUCH CONDITIONS IN THE HWO.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 317 PM CDT SUN JUN 23 2013
MONDAY NIGHT...A VORT MAX LOCATED OVER THE HIGH PLAINS WILL TRACK
EAST ACROSS THE FORECAST AREA. THUNDERSTORMS THAT INITIALLY FORM
ACROSS THE HIGH PLAINS DURING THE MONDAY AFTERNOON HOURS WILL SLIDE
EAST DURING THE EVENING AND OVERNIGHT HOURS...AND IF THEY HOLD
TOGETHER MAY BRING RAIN TO PORTIONS OF THE FORECAST AREA. IN
ADDITION TO RAIN...SOME OF THESE THUNDERSTORMS MAY BE SEVERE WITH
LARGE HAIL AND DAMAGING WINDS POSSIBLE DURING THE EVENING HOURS.
INSTABILITY IS HIGH AND DEEP LAYER SHEAR IS MORE MODEST BUT
SUFFICIENT FOR SEVERE STORMS. THE LIMITING FACTOR WILL BE THE WARM
MID LEVEL CAP AND THUS CONFIDENCE IN THUNDERSTORM DEVELOPMENT AND
COVERAGE IS STILL FAIRLY LOW WITH SLIGHT POPS. THE 12Z ECMWF AND 12Z
NAM FAVOR OUR WEST AND NORTH FOR STORMS...WHILE THE 12Z GFS
HIGHLIGHTS OUR SOUTHEASTERN ZONES. THE ECMWF AND NAM MAKE MORE SENSE
WITH FAVORING NORTH AND WEST ZONES BASED ON THE EXPECTED UPPER WAVE
LOCATION AND THE INCREASING STRENGTH OF THE CAP AS YOU HEAD SOUTH.
TUESDAY AND WEDNESDAY...THE PATTERN WILL BE FAIRLY ZONAL WITH ALL
OF THE BETTER UPPER FLOW AND SHORT WAVES TRACKING ACROSS THE
NORTHERN TIER STATES. AN UPPER RIDGE WILL SLOWLY BEGIN TO BUILD
ACROSS THE SOUTHWEST CONUS STARTING ON WEDNESDAY. A SFC TROUGH AXIS
WILL TRACK EAST THROUGH OUR FORECAST AREA LATE ON TUESDAY AND TURN
THE WINDS TO NORTHERLY BY WEDNESDAY. HOWEVER...A STRONG CAP SHOULD
RESULT IN DRY CONDITIONS FOR MOST AREAS AND WILL CONTINUE TO CALL
FOR A DRY FORECAST...BUT CAN NOT COMPLETELY RULE OUT AN ISOLATED
THUNDERSTORM...HENCE THE 10 PERCENT POPS. TUESDAY WILL BE SCORCHER
WITH HIGHS WELL INTO THE 90S ACROSS NEBRASKA TO OVER 100 ACROSS MUCH
OF NORTHERN KANSAS. TEMPERATURES WILL FALL A FEW DEGREES WITH THE
NORTH WINDS ON WEDNESDAY...BUT CONTINUE TO EXPECT 90S FOR HIGHS.
THURSDAY THROUGH SUNDAY...THERE IS A SHIFT IN THE UPPER PATTERN AS
AN UPPER RIDGE STRENGTHENS ACROSS THE ROCKIES AND AN UPPER TROUGH
PERSISTS ACROSS THE EASTERN CONUS. THIS WILL RESULT IN NORTHWESTERLY
FLOW ALOFT FOR OUR FORECAST AREA. MOST AREAS WILL BE DRY THROUGHOUT
THIS PERIOD GIVEN A LACK OF FORCING. THERE IS A SLIGHT CHANCE OF
THUNDERSTORMS ON THURSDAY INTO THURSDAY NIGHT...BUT MOST RESENT
MODEL RUNS ARE STARTING TO BACK OFF OF THIS ALREADY RATHER SLIGHT
CHANCE OF PRECIPITATION. ANOTHER WEAK COOL FRONT WILL TRY TO WORK
ITS WAY THROUGH AT SOME POINT THURSDAY NIGHT OR FRIDAY...BUT THURSDAY
SHOULD STILL BE A HOT DAY WITH 90S ACROSS NEBRASKA TO NEAR 100 IN
KANSAS. THE COOLER WEATHER WILL SETTLE IN ON FRIDAY AND SATURDAY
WITH EASTERLY TO NORTHEASTERLY SFC WINDS. THIS COOLER FETCH SHOULD
DROP HIGHS BACK INTO THE LOWER AND MID 90S ON FRIDAY...AND THEN 80S
ACROSS NEBRASKA TO LOWER 90S OVER KANSAS ON SATURDAY. TEMPERATURES
BEGIN TO WARM BACK UP ON SUNDAY WITH EVERYONE BACK IN THE 90S.
OVERALL...TEMPERATURES WILL NOT VARY THAT MUCH AND REMAIN RATHER
TOASTY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 115 AM CDT MON JUN 24 2013
GENERALLY VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. CONVECTION
DEVELOPING OFF THE HIGHS PLAINS EARLY TONIGHT WILL SHIFT NEWD AND MAY
IMPACT THE GRI TERMINAL AROUND 9-11Z AND WILL INCLUDE A TEMPO GROUP
FOR THIS. OTHERWISE SOME MVFR CIGS ARE AROUND THE REGION...BUT WE
EXPECT MUCH OF THIS TO LIFT NWD OVERNIGHT BUT SOME MVFR CIGS/VISBY
ARE POSSIBLE IN THE TSRA. OTHERWISE SOUTHERLY WINDS WILL INCREASE
THROUGH THE DAY ON MON.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...
LONG TERM...
AVIATION...BOUSTEAD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
105 AM CDT MON JUN 24 2013
.UPDATE...
ISSUED AT 105 AM CDT MON JUN 24 2013
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE AS THE INHERITED
FORECAST IS WELL ON TRACK. LEFT FOG OUT OF THE FORECAST FOR
NOW...HOWEVER...WILL CONTINUE TO MONITOR THROUGH THE NIGHT WITH
LOW TEMPERATURE-DEW POINT SPREADS ESPECIALLY ACROSS THE NORTH WITH
LIGHT WINDS AND CLEAR SKIES. DID REMOVE THE MENTION OF A SLIGHT
CHANCE OF THUNDERSTORMS ACROSS THE FAR SOUTHWEST LATE TONIGHT WITH
LARGE SCALE SUBSIDENCE AND ONLY WEAK LOW LEVEL WARM AIR ADVECTION.
IN REGARDS TO THE SEVERE THREAT ON MONDAY...SPC IN THEIR DAY ONE
OUTLOOK HAS PLACED THE ENTIRE CWA UNDER A SLIGHT RISK. SEE THE SPC
DAY 1 OUTLOOK FOR DETAILS.
UPDATE ISSUED AT 952 PM CDT SUN JUN 23 2013
WANING CONVECTION OVER NORTHERN FOSTER COUNTY SHOULD QUICKLY
DIMINISH IN THE NEXT HOUR. WILL KEEP A CHANCE POP HERE FOR THE
NEXT HOUR. OTHERWISE...ISOLATED SHOWERS FROM SOUTHERN SASKATCHEWAN
INTO NORTHWEST NORTH DAKOTA CONTINUE TO QUICKLY DIMINISH. WILL NOT
MENTION POPS HERE TONIGHT. OTHERWISE...CURRENT FORECAST IS IN GOOD
SHAPE. DID ADJUST CLOUD COVER LOWER FOR MOST AREAS THIS EVENING
AND WAS A LITTLE SLOWER TO INCREASE CLOUD COVER AFTER MIDNIGHT IN
THE WEST. LATEST 01Z HRRR IS BRINGING SOME LIGHT QPF INTO THE FAR
SOUTHWEST BETWEEN 11Z-12Z MONDAY...SO WILL KEEP A SLIGHT CHANCE OF
CONVECTION IN THE FAR SOUTHWEST TOWARD MORNING.
UPDATE ISSUED AT 703 PM CDT SUN JUN 23 2013
MAIN ISSUE WITH THE EARLY EVENING UPDATE IS CURRENT SHOWER AND
THUNDERSTORM ACTIVITY. CURRENTLY SHOWER AND THUNDERSTORMS WERE
LOCATED FROM JUST NORTH OF GARRISON...TO MINOT...AND THEN
NORTHEAST TO ROLETTE COUNTY. WITH A FEW STRAY SHOWERS EXTENDING
BACK TO NEAR CROSBY. ACTIVITY HAS SHOWN A DECREASE IN INTENSITY
IN THE PAST TWO HOURS. HAVE ADJUSTED POPS A BIT LOWER AND
DECREASED AREAL COVERAGE. EXPECT ACTIVITY TO CONTINUE TO DECREASE
OVER THE NEXT FEW HOURS...AND DISSIPATE COMPLETELY BY AROUND 10 PM.
OTHERWISE NO SIGNIFICANT CHANGES TO THE CURRENT FORECAST.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 345 PM CDT SUN JUN 23 2013
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE SCATTERED
STRONG THUNDERSTORMS NORTH THIS AFTERNOON/EARLY EVENING...FOLLOWED
BY ANOTHER CHANCE OF POSSIBLY STRONG TO SEVERE STORMS MONDAY
AFTERNOON.
CURRENTLY...UPPER LOW OVER CENTRAL SASKATCHEWAN WITH A STRONG
EMBEDDED IMPULSE ROTATING NORTHEAST THROUGH THE DEVILS LAKE BASIN
INTO NORTHEAST NORTH DAKOTA. STEEP LAPSE RATES WITH COLD AIR ALOFT
HAS TRIGGERED A FEW STRONGER STORMS NEAR THE INTERNATIONAL
BORDER. A FEW STRONGER STORMS ARE POSSIBLE AND PERHAPS PULSE
SEVERE WITH MUCAPE 1-2K J/KG. LACK OF SUPPORTIVE 0-6KM SHEAR WILL
LIMIT UPDRAFT LONGEVITY. STORMS ARE DIURNAL IN NATURE AND SHOULD
QUICKLY DISSIPATE INTO EARLY THIS EVENING AS THE NOCTURNAL
INVERSION DEVELOPS. BEFORE THIS HAPPENS...WILL NEED TO MONITOR FOR
POSSIBLE FUNNELS/LAND SPOUTS WITH THE NON-SUPERCELL TOR PARAMETER
ELEVATED OVER NORTHWEST NORTH DAKOTA.
MOSTLY CLEAR THE REMAINDER OF THIS EVENING IN THE WAKE OF THE
CURRENT CONVECTION. MODELS DEVELOP A LOW LEVEL JET LATER THIS
EVENING INTO THE OVERNIGHT ACROSS WESTERN SOUTH DAKOTA NOSING
INTO SOUTHWEST NORTH DAKOTA LATE AROUND OR AFTER 09Z. WILL
INTRODUCE SLIGHT CHANCES FOR THUNDER FAR SOUTHWEST 9-12Z GIVEN
THIS FORCING ALONG WITH INCREASING BOUNDARY LAYER MOISTURE. KEPT
SLIGHT CHANCE POPS GOING THROUGH THE MORNING HOURS WEST.
BOUNDARY LAYER MOISTURE CONTINUES TO ADVECT INTO THE REGION
THROUGHOUT THE DAY MONDAY THANKS TO STRONG MID LEVEL FLOW/MOISTURE
FETCH FROM THE SOUTHERN PLAINS INTO THE DAKOTAS WITH SFC DEWPOINT
TEMPS RISING INTO THE 60S AREA WIDE. THIS WILL CONTRIBUTE TO
INCREASING INSTABILITY WITH MUCAPES PROJECTED TO INCREASING TO
AROUND 2500 J/KG IN THE AFTERNOON AS SFC TEMPS WARM INTO THE
LOW/MID 80S. WHILE A CAPPING INVERSION LOOKS TO BE IN PLACE...A
POTENTIAL TRIGGER VIA A LEAD SHORT WAVE IMPULSE IS FORECAST TO
APPROACH THE DAKOTAS MONDAY AFTERNOON LEADING TO CONVECTIVE
INITIALIZATION. WILL MAINTAIN POPS AS IS FOR NOW DUE TO THE
UNCERTAINTY DURING THE AFTERNOON WHERE AND IF STORMS WILL
DEVELOP.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 345 PM CDT SUN JUN 23 2013
POTENTIAL FOR SEVERE THUNDERSTORMS CONTINUE MONDAY NIGHT AND
TUESDAY. SOUTHWEST FLOW ALOFT TRANSITIONS TO A WESTERLY FLOW
WEDNESDAY...THEN NORTHWEST AS RIDGING DEVELOPS OVER THE FOUR
CORNERS. HOWEVER THE RIDGE FLATTENS SATURDAY AS A SHORTWAVE ROLLS
THROUGH. THIS SHOULD BE TEMPORARY AS THE LONG TERM MODEL SUITE THEN
SHOWS A STRONGER AMPLIFICATION OF THE RIDGE TO COMMENCE ACROSS THE
INTERMOUNTAIN WEST JUST BEYOND THIS EXTENDED PERIOD.
FOR MONDAY NIGHT...WITH STRONG WARM/MOIST AIR ADVECTION IN
THE LOWER LEVELS COMBINED WITH A COUPLE OF SHORTWAVES TRANSVERSING
THROUGH VIA A SOUTHWEST FLOW ALOFT...THIS SHOULD BE ENOUGH TO
PROMOTE CONVECTION THROUGH THE NIGHT. SURFACE DEWPOINTS IN THE UPPER
60S TO AROUND 70 WILL YIELD MUGGY CONDITIONS AND VERY WARM OVERNIGHT
LOWS MONDAY NIGHT. THE STRONGEST SHORTWAVE SHIFTS THROUGH ON TUESDAY
AS A SURFACE COLD FRONT MOVES FROM WEST TO EAST. EXPECTING
THUNDERSTORMS LIKELY ALONG AND AHEAD OF THE FRONT. THE SCENARIO THAT
APPEARS MOST LIKELY IS THUNDERSTORMS WILL BE ONGOING FROM MONDAY
NIGHT AND CONTINUE FOR MOST OF TUESDAY INTO TUESDAY EVENING. THE
COLD FRONT SHOULD CLEAR THE JAMES RIVER VALLEY BY 06Z WEDNESDAY.
WEDNESDAY LOOKS MOSTLY DRY WITH THE EXCEPTION OF NORTH CENTRAL NORTH
DAKOTA WHERE A SHORTWAVE WILL MOVE THROUGH PRODUCING A SLIGHT CHC OF
SHOWERS/THUNDERSTORMS. RIDGING WEST OF NORTH DAKOTA AS MENTIONED
ABOVE WILL PROMOTE DRY WEATHER FOR THURSDAY/FRIDAY...THEN A CHANCE
FOR THUNDERSTORMS SATURDAY THROUGH SUNDAY WITH A SHORTWAVE MOVING
THROUGH.
WARMEST HIGH TEMPERATURES WILL BE TUESDAY WITH MID TO UPPER 80S
ALONG WITH HUMID CONDITIONS. DRIER AIR/LOWER DEWPOINTS CAN BE
EXPECTED FOR THE REST OF THE WEEK WITH HIGHS COOLING TO THE UPPER
70S NORTH AND LOWER 80S SOUTH THURSDAY THROUGH SATURDAY. OVERNIGHT
LOWS IN THE 60S TO NEAR 70 TUESDAY MORNING...THEN UPPER 50S FOR THE
REST OF THE LONG TERM PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 105 AM CDT MON JUN 24 2013
VFR CONDITIONS IN GENERAL ARE EXPECTED ACROSS WESTERN AND CENTRAL
NORTH DAKOTA FOR THE 06 UTC TAF CYCLE. CANNOT RULE OUT PATCHY FOG
LATE TONIGHT...HOWEVER...DUE TO UNCERTAINTY AND LOW
COVERAGE...WILL LEAVE THE MENTION OUT OF THE TAFS FOR NOW. ON
MONDAY THE MAIN THREAT WILL BE THE POTENTIAL FOR SEVERE
THUNDERSTORMS AREA WIDE LATE MONDAY AFTERNOON AND THROUGH THE
EVENING. FOR NOW GIVEN UNCERTAINTY...CODED AS VCTS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...NH
LONG TERM...KS
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1149 PM CDT SUN JUN 23 2013
.UPDATE...
ISSUED AT 1145 PM CDT SUN JUN 23 2013
THE SHOWERS IN THE DVL BASIN HAVE NOW DISSIPATED. REST OF THE
NIGHT WILL BE DRY. KEPT LOWS AS FCST.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 313 PM CDT SUN JUN 23 2013
CONVECTION CHANCES CONTINUE TO BE THE PRIMARY FORECAST PROBLEM FOR
THE PERIOD.
WV LOOP SHOWS THE MAIN SHORTWAVE IS CURRENTLY IN THE PROCESS OF
LIFTING THROUGH THE CWA ON ITS WAY INTO CANADA. THE MAIN SFC LOW
IS ALREADY IN SOUTHERN MANITOBA...WITH ALL BUT THE FAR
NORTHEASTERN CWA SEEING WESTERLY WINDS ON THE SOUTH SIDE OF THE
LOW. THE RAIN BAND FROM THIS MORNING HAS LIFTING NORTH INTO
CANADA...AND SOME CLEARING HAS BEEN GOING ON ALTHOUGH WITH PRETTY
LOW CONVECTIVE TEMPS CU HAS REDEVELOPED RAPIDLY. THERE HAS BEEN A
DECREASE IN MOISTURE AS THE WEST WINDS BRING IN DRIER AIR...BUT
THERE IS STILL A DECENT AMOUNT OF HUMIDITY AND WITH SOME CLEARING
CAPE HAS REACHED AROUND 1000 J/KG ACROSS THE CENTRAL CWA. WHILE
THE BEST LIFT WILL BE QUICKLY MOVING OFF TO THE NORTH THIS
EVENING...THERE IS ENOUGH INSTABILITY HANGING AROUND THAT CANNOT
COMPLETELY RULE OUT THUNDERSTORM REDEVELOPMENT...AND THE RAP AND
HRRR SHOW SIGNS OF THIS ALTHOUGH STRENGTH DOES NOT SEEM IMPRESSIVE
AT THIS POINT. WILL KEEP SOME 30-60 POPS GOING MAINLY NORTH OF THE
HIGHWAY 2 CORRIDOR THROUGH EARLY EVENING BEFORE WE GO DRY AFTER
MIDNIGHT.
MONDAY SHOULD BE FAIRLY QUIET WITH WEAK UPPER RIDGING BETWEEN
SYSTEMS. WINDS WILL SHIFT BACK TO THE SOUTH AS A SFC TROUGH BEGINS
TO DEEPEN OVER THE ROCKIES/WESTERN PLAINS. 850MB TEMPS CLIMB BACK
UP TOWARDS THE UPPER TEENS C AND WITH PLENTY OF SUN WE SHOULD BE
ABLE TO CLIMB INTO THE MID 80S ACROSS MOST OF THE AREA. THE QUIET
CONDITIONS WILL BE SHORT LIVED AS MODELS SHOW SOME INDICATION OF A
WEAK SHORTWAVE MOVING IN MONDAY NIGHT. THINK THERE COULD BE SOME
STORMS MOVING IN FROM THE WEST MONDAY NIGHT...WITH THE MODELS
SHOWING SOME ELEVATED INSTABILITY LIFTING INTO THE CWA OVERNIGHT.
KEPT SOME POPS AROUND 30 PERCENT.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 313 PM CDT SUN JUN 23 2013
THINK THAT THE BETTER CHANCES FOR MORE SIGNIFICANT STORMS WILL BE
TUESDAY WHEN A FAIRLY STRONG SHORTWAVE TROUGH MOVES INTO THE
DAKOTAS. THE SFC TROUGH AXIS WILL MOVE INTO CENTRAL ND...WITH
SOUTHEASTERLY WINDS AHEAD OF IT AND GOOD LOW LEVEL CONVERGENCE.
INSTABILITY WILL DEPEND ON EXACTLY ANYTHING OVERNIGHT
EVOLVES...BUT THERE IS THE POSSIBILITY OF MORE THAN 2000 J/KG OF
CAPE. CONTINUED TO KEEP FAIRLY HIGH POPS FOR THUNDERSTORMS TUESDAY
INTO TUESDAY NIGHT...BUT IS A BIT EARLY FOR ANY SEVERE MENTION AT
THIS TIME.
SOME PRECIP MAY LINGER INTO WEDNESDAY MORNING...BUT OVERALL THERE
SHOULD BE A DRYING TREND AS THE UPPER SHORTWAVE PULLS OFF TOWARDS
THE GREAT LAKES. TEMPS SHOULD BE FAIRLY SEASONABLE IN THE LOW 80S.
WEDNESDAY NIGHT TO SATURDAY NIGHT...MODELS IN GOOD AGREEMENT WITH
RETROGRADING AND AMPLIFYING WESTERN CONUS RIDGE AND GREAT LAKES
TROUGH AT 500MB. AS A RESULT NW FLOW ACROSS THE NORTHERN PLAINS
WILL DEVELOP. THIS WILL MAKE FOR SEASONAL END OF JUNE TEMPERATURES
AND NEARLY CLIMO POPS AS THE TIMING OF ANY WEAK SHORT WAVES
FEATURE WILL NEED TO COINCIDE WITH PEAK HEATING TO INITIATE ANY
DIURNALLY DRIVEN CONVECTION AND OVERALL COVERAGE IS EXPECTED TO BE
LOW...THUS THE LOW POPS IN THE EXTENDED.
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1252 PM CDT SUN JUN 23 2013
LOW PRESSURE TRACKING ALMOST DUE NORTH ALONG RED RIVER NEAR HCO WITH
TROUGH AND EDGE OF RAIN NOW THRU TVF. EXPECT MVFR CIGS TO CONTINUE
TO IMPROVE WITH DRIER AIR MIXING IN ON WESTERLY GUSTS 20 TO
30KTS...SOME ISOLATED SHOWERS THIS AFTERNOON POSSIBLE...WITH VFR
CONDITIONS EXPECTED THIS EVENING AND OVERNIGHT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1145 PM CDT SUN JUN 23 2013
LTITLE CHANGE FROM PREV FCST. WINDS DOWN BACKING MORE SOUTH-
SOUTHWEST IN MOST AREAS AND UNDER 10 KTS. IT WILL STAY THIS WAY
TIL JUST PAST SUNRISE. BY 16Z EXPECT WINDS TO TURN A BIT MORE
SOUTHWEST AND SOUNDINGS INDICATE A PRETTY GOOD MIXED LAYER SO
WOULDNT BE SUPRISED TO SEE SOME GUSTS TO 20 KTS OR SO DURING PEAK
HEATING MONDAY. VFR ALL DAY MONDAY WITH A FEW CU OR SOME CIRRUS
MOVING IN. SOME AC MOVING INTO DVL-FAR REGIONS MON EARLY EVE.
COULD BE SOME THUNDER BY 06Z TUE IN DVL-FAR BUT LEFT OUT SINCE
VERY UNCERTAIN.
&&
.HYDROLOGY...
ISSUED AT 628 PM CDT SUN JUN 23 2013
NEW WARNINGS WERE DONE FOR THE BUFFALO RIVER AT SABIN AND DILWORTH
FOR MINOR FLOODING.
NEW WARNINGS ACROSS THE SOUTHERN VALLEY AT HARWOOD...WEST
FARGO... KINDRED...ABERCROMBIE WITH AN INCREASE OF FLOODING TO
MODERATE NOW EXPECTED AT WAHPETON AND FARGO AS THE AREA RIVERS
RESPOND TO LAST NIGHTS RAINFALL OF ONE TO TWO INCHES ON ALREADY
SATURATED SOILS. ALSO...MAPLETON WARNING WAS CANCELLED AS THE
RIVER FELL BELOW FLOOD STAGE EARLIER TODAY.
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...RIDDLE
SHORT TERM...JR
LONG TERM...JR/JK
AVIATION...RIDDLE
HYDROLOGY...WJB/JK
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1233 AM CDT MON JUN 24 2013
.UPDATE...
ISSUED AT 930 PM CDT SUN JUN 23 2013
LOW LEVEL JET STARTING TO HELP GENERATE SHOWERS AND THUNDERSTORMS
FROM SOUTHEAST NEBRASKA INTO SOUTHERN IOWA. THESE WILL LIKELY
CONTINUE TO DEVELOP NORTHWARD THROUGH THE EVENING. ALTHOUGH THE LOW
LEVEL JET ORIENTATION WOULD SUGGEST THAT THE BEST COVERAGE WILL
REMAIN SOUTHEAST OF OUR CWA. THIS IS SUPPORTED BY THE LATEST HRRR.
HOWEVER DID GO AHEAD AND ADD IN CHANCE POPS ACROSS OUR FAR SOUTH...AS
CANNOT COMPLETELY RULE OUT A STORM MAKING IT UP THERE AFTER ABOUT
08Z. ATTENTION THEN TURNS TO A WAVE COMING OUT OF THE ROCKIES.
CONVECTION ACROSS NORTHEAST COLORADO SHOULD MOVE EAST THROUGH
NEBRASKA OVERNIGHT. LIFT AND MOISTURE TRANSPORT AHEAD OF THIS WAVE
SHOULD ALLOW CONVECTION TO MAINTAIN ITSELF. PREFER THE FASTER TIMING
OF THE HRRR AS COMPARED TO THE NEW SLOWER 4KM NAM. THIS WOULD BRING
THE THREAT INTO OUR SOUTHWEST AROUND 12Z...PUSHING NORTHEAST THROUGH
THE MORNING HOURS. THIS FITS PRETTY WELL WITH THE GOING FORECAST...SO
DID NOT MAKE ANY CHANGES TO POPS TOMORROW. AS MENTIONED
BELOW...SEVERE THREAT SHOULD BE LOW WITH THIS MORNING
CONVECTION...ALTHOUGH MUCAPE APPROACHING 2000 J/KG MAY BE ENOUGH FOR
A FEW MARGINAL HAIL PRODUCING STORMS. TIMING OF THIS WAVE IS STILL
UNCERTAIN. IF IT ENDS UP SLOWER AND WE ARE ABLE TO GET MORE DAYTIME
HEATING AHEAD OF IT...THE SEVERE POTENTIAL WOULD PROBABLY INCREASE.
STILL TOUGH TO SAY WHAT HAPPENS TOMORROW NIGHT UNTIL WE SEE WHAT THE
FIRST WAVE DOES. SEEMS LIKELY STORMS FIRE IN THE WESTERN PLAINS
DURING THE AFTERNOON WITH A SECOND WAVE. WHETHER THESE SURVIVE INTO
OUR CWA IS STILL UP IN THE AIR...WITH MOST CONVECTION ALLOWING MODELS
SAYING NO...AND THE LOWER RESOLUTION NAM...GFS AND EC SUGGESTING YES.
PROBABLY DEPENDENT ON EXTENT OF DRYING...SUBSIDENCE AND CAPPING BEHIND
THE FIRST WAVE. WILL JUST HAVE TO CONTINUE TO MONITOR TRENDS.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 341 PM CDT SUN JUN 23 2013
A FRONTAL BOUNDARY CONTINUES TO PUSH THROUGH THE EASTERN PORTION OF
THE CWA THIS AFTERNOON AND IS EXPECTED TO EXIT THE AREA LATE THIS
AFTERNOON. CONVECTION WHICH WE EARLIER THOUGHT MIGHT DEVELOP IN OUR
SOUTHEAST LATE THIS AFTERNOON NOW LOOKS TO HOLD OFF UNTIL LATER IN
THE EVENING...WHEN THE BOUNDARY IS OUT OF OUR AREA...SO DO NOT
ANTICIPATE ANY DEVELOPMENT OVER OUR AREA. OTHERWISE...THE REMAINDER
OF THE NIGHT SHOULD BE QUIET AS WEAK HIGH PRESSURE BUILDS INTO THE
REGION. THIS WILL ALLOW FOR WINDS TO DIE OFF...AND CANNOT RULE OUT
SOME PATCHY FOG DEVELOPMENT WITH RECENT RAINS...THOUGH DID NOT
INCLUDE IN FORECAST AT THIS POINT WITH LOW CONFIDENCE. THE FORECAST
BECOMES MORE CHALLENGING LATER TONIGHT INTO MONDAY...WITH MODELS
DIFFERING ON THE TIMING AND STRENGTH OF ANOTHER SHORT WAVE LIFTING
UP OVER THE AREA DURING THE DAY ON MONDAY. MONDAYS SHORT WAVE IS
CURRENTLY VISIBLE ON THE WATER VAPOR IMAGERY NEAR LAS VEGAS NV. THE
GFS/GEM/4KM NAM AND SREF OFFER THE WETTER SOLUTIONS AS THEY ARE
STRONGER IN THE MID LEVELS...WHILE THE ECMWF AND NAM KEEP IT DRY
DURING THE DAYTIME HOURS...ALTHOUGH THE NAM DOES SHOW SOME WEAK PV
ON THE 1.5 SURFACE. ELECTED TO GO WITH THE WETTER SOLUTIONS WITH
850 MB THETA E ADVECTION INCREASING OVER THE AREA AS THE LOW
LEVEL JET CRANKS UP OUT OF EASTERN NEBRASKA. IN ADDITION THERE
WILL BE INSTABILITY AND SOME SHEAR...THOUGH IN THE ABSENCE OF
CAPPING WOULD EXPECT NO REAL UPDRAFT ENERGY TO BE STORED UP. SO
OTHER THAN SOME POSSIBLE SMALL HAIL WOULD NOT EXPECT SEVERE STORMS
DURING THE DAY. THIS OF COURSE WILL IMPACT HIGH TEMPERATURES...SO
WENT WITH COOLER GUIDANCES WITH HIGHS INTO THE LOWER 80S NORTHEAST
TO THE UPPER 80S ALONG THE MISSOURI RIVER CORRIDOR.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 341 PM CDT SUN JUN 23 2013
MONDAY NIGHT IS THE MOST ACTIVE PERIOD IN THE LONGER TERM. ANOTHER
STRONGER SHORT WAVE FOLLOWS MONDAY WAVE...WHICH WATER VAPOR SHOWS
CURRENTLY OFF OF THE CA COAST. INTERESTINGLY...THE HI RES MODELS
WHICH ARE SO ACTIVE ON MONDAY LEAVE MONDAY NIGHT DRY. HOWEVER THE
NAM AND ECMWF ARE WET...ESPECIALLY ALONG AND NORTH OF I 90. THE
ECMWF HAS BEEN VERY CONSISTENT WITH THIS FEATURE FOR 4 OR 5 DAYS
NOW. SO IT IS VERY HARD TO IGNORE. THE NAM IS STRONG WITH THE
PV 1.5...AND ABUNDANT INSTABILITY AND WIND SHEAR CONTINUES. MOST
OF THE RAINFALL WILL OCCUR IN THE EVENING HOURS...AGAIN WITH THE
HIGHEST CHANCES FOR HEAVIER RAINFALL ALONG AND NORTH OF I 90. NAM
PWATS IN THOSE AREAS AVERAGE 1.5 TO 2.0 INCHES AND SOME SEVERE
WEATHER IS POSSIBLE GIVEN THE INSTABILITY PARAMETERS. THE WAVE
QUICKLY EXITS AFTER MIDNIGHT...WHICH WILL LEAVE TUESDAY DRY AND
VERY WARM AND HUMID.
UPPER RIDGING THEN BUILDS AS ADVERTISED AND RETROGRADES WESTWARD
BY LATE WEEK AND NEXT WEEKEND. A SURFACE BOUNDARY MOVES THROUGH
OUR AREA LATE TUESDAY NIGHT SHIFTING OUR WINDS TO THE NORTHWEST
FOR WEDNESDAY. WITH BETTER MIXING...TEMPERATURES WILL STILL BE
QUITE WARM...WITH LESS HUMID CONDITIONS WEST OF I 29. AS THE UPPER
RIDGE RETROGRADES TO THE WEST CREATING A HIGHLY AMPLIFIED PATTERN...
IT STILL LOOKS AS THOUGH TEMPERATURES WILL START A COOLING TREND
ON THURSDAY...LASTING THROUGH THE WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1231 AM CDT MON JUN 24 2013
ONE WAVE WHICH RECENTLY PUSHED PAST THE FOUR CORNERS WILL MOVE
INTO THE AREA EARLY THIS MORNING. GIVEN THE LOW LEVEL JET...AND
APPARENT BOUNDARY ACROSS SOUTHEAST/CENTRAL NEBRASKA...EXPECT A
FEW STORMS TO DEVELOP ALONG WARM ADVECTIVE WING AND IMPACT KSUX
AREA AFTER 09Z...AND THEN A BETTER COVERAGE OF SHOWERS/STORMS BY
MORNING HOURS FOR KFSD AND KSUX...BUT EXITING NORTHEAST FAIRLY
QUICKLY. UPSTREAM AND STRONGER WAVE UPSTREAM AROUND RENO NV WILL
FOLLOW...AND WILL LIKELY RESULT IN ADDITIONAL CONVECTION ACROSS
THE AREA...BUT FOR NOW HELD OFF MENTION UNTIL AFTER 00Z.
PROBABILITY OF MVFR FOG IS FAIRLY LOW...LIKELY HIGHEST AROUND
KSUX...BUT WILL ALSO HAVE INITIAL INCREASE IN CLOUDS FROM
CONVECTION TO SOUTH...AND WILL NOT MENTION ON THIS FORECAST SET.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
UPDATE...CHENARD
SHORT TERM...JM
LONG TERM...MJ
AVIATION...08
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1223 AM CDT MON JUN 24 2013
.UPDATE...
SEE UPDATED AVIATION DISCUSSION BELOW.
WINDS HAVE GONE LIGHT LATE THIS EVENING UNDER CLEAR SKIES AND
SURFACE HIGH PRESSURE RIDGING. THE WINDS WILL TURN SOUTH BEHIND
THIS RETREATING HIGH PRESSURE AREA TONIGHT. ALREADY HAVE MID LEVEL
WAA CLOUDS/ACCAS AND COOLING TOPS IN WY/SE MT LATE THIS EVENING
MOVING QUICKLY EAST. THESE WILL CONTINUE TO MOVE EAST AND MAY
BECOME HIGH BASED SHOWERS/THUNDER AS THEY MOVE INTO WESTERN SD AND
INTO OUR WESTERN CWA LATER TONIGHT. THE LATEST HRRR MODEL SHOWS
SOME SPOTTY QPF LATER TONIGHT. ALREADY HAVE IN SLIGHT CHANCES WEST
IN THE CWA AFTER MIDNIGHT.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT
THE ACTIVE SUMMER PATTERN CONTINUES EARLY THIS WEEK AS RETURN
FLOW MOISTURE AND INSTABILITY MAKE A QUICK RETURN TO THE WESTERN
ZONES OVERNIGHT AND SPREADS EAST MONDAY AND MONDAY EVENING.
MODELS ARE AGAIN OFFERING A CHALLENGING FORECAST WITH TIMING AND
STRENGTH OF SHORTWAVES AND CONVECTION...BUT THUNDERSTORMS LOOK
LIKE A GOOD BET MONDAY NIGHT MOST LOCATIONS AND AGAIN TUESDAY
NIGHT IN THE EAST. SPC HAS AREA IN SLIGHT RISK FOR MONDAY NIGHT
AND THE EASTERN PORTION FOR TUESDAY.
DESPITE RISING HEIGHTS...DEEP SOUTHWEST FLOW ALOFT WILL CONTINUE
TO EJECT SHORTWAVES INTO THE UPPER PLAINS. WITH INSTABILITY
RETURN IN THE WEST LATE TONIGHT HAVE ADDED SMALL POPS TO THE
FORECAST FOR AREAS ALONG AND WEST OF THE MISSOURI RIVER.
HEAT...MOISTURE AND INSTABILITY WILL INCREASE THE NEXT FEW DAYS
WITH TEMPS CLIMBING INTO THE UPPER 80S AND MID 90S BY TUESDAY.
THE HEAT INDEX WILL CLIMB INTO THE MID TO UPPER 90S ON TUESDAY.
AS MENTIONED ABOVE...MODELS IN ARE NOT IN VERY GOOD AGREEMENT
WITH TIMING OF CONVECTION...BUT OVERALL FEEL CONFIDENT FOR
THUNDERSTORMS FOR BOTH MONDAY AND TUESDAY EVENINGS...POSSIBLY
SEVERE AS INSTABILITY INCREASES.
.LONG TERM...WEDNESDAY THROUGH SUNDAY
IT APPEARS THE THEMES RUNNING THROUGHOUT THE EXTENDED ARE WARM AND
MOSTLY DRY. AT THIS POINT...POPS/WX MENTION DO NOT SHOW UP IN THE
OUT PERIODS BASICALLY UNTIL SATURDAY LATE AFTERNOON/EARLY EVENING.
UNTIL THEN...REBOUNDING MID/UPPER LEVEL HEIGHTS ARE FORECAST TO
DEVELOP ACROSS THE WESTERN TWO-THIRDS OF THE CONUS STARTING
WEDNESDAY AND PERSIST THROUGH THE END OF THE PERIOD. A LOW
PRESSURE SYSTEM IS PROGGED TO TRY WORKING THROUGH THE TOP OF THE
RIDGE...IN EFFECT...FLATTENING IT SOMEWHAT OVER THE WEEKEND AND
BRINGING A SMALL CHANCE AT CONVECTION ACROSS THE CWA BY SATURDAY
EVENING. AT THIS TIME...700HPA THERMAL PROGS ARE AT OR ABOVE +14C
ON SATURDAY...SO IT WILL TAKE QUITE A BIT OF MOISTURE/INSTABILITY
AND STRONG FORCING AROUND TO GET STORMS TO DEVELOP IN THAT WARM OF
A MID-LEVEL ENVIRONMENT. SPEAKING OF WARM...WITH HEIGHTS RISING IN
THE ATMOSPHERE...A GOOD CHUNK OF THE EXTENDED SHOULD BE LOOKING AT
NEAR TO ABOVE NORMAL HIGH TEMPERATURES IN THE 80S AND 90S DURING
THE MID TO LATE PORTIONS OF THE WEEK.
&&
.AVIATION...
06Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
VFR CONDITIONS ARE EXPECTED AT ALL TERMINALS THROUGH TONIGHT AND
MONDAY. AN UPPER LEVEL LOW PRESSURE TROUGH ALONG WITH RETURNING
WAA WILL SPREAD MID LEVEL CLOUDS ACROSS THE REGION THROUGH MONDAY.
WITH INSTABILITY ALSO RETURNING/INCREASING...SOME
SHOWERS/THUNDERSTORMS SHOULD ALSO DEVELOP MAINLY LATE TONIGHT AND
MONDAY. LEFT ANY MENTION OUT OF THE TERMINALS AT THIS TIME WITH
THE UNCERTAINTY OF LOCATION AND TIMING INVOLVED. SOUTHEAST WINDS
WILL ALSO BECOME BREEZY ON MONDAY AT 15 TO 20 KNOTS WITH HIGHER
GUSTS AT MBG AND PIR.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...WISE
SHORT TERM...DORN
LONG TERM...SCARLETT
AVIATION...WISE
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
310 AM EDT MON JUN 24 2013
.SHORT TERM (TODAY AND TONIGHT)...
SOME SHOWERS ARE PERSISTING IN THE SOUTHERN HALF OF THE AREA THIS
MORNING...AND THE RUC SHOWS AN AREA OF LOW LEVEL MOISTURE
CONVERGENCE IN THIS AREA. THE RUC SHOWS THIS WEAKENING BY 12Z...BUT
WILL INCLUDE A SLIGHT CHANCE POP IN ALL AREAS THROUGH THE MORNING.
IN THE AFTERNOON...WE WILL SEE A REMNANT VORT MAX FROM CONVECTION
OVER W KY ENTER THE AREA...AND THE NAM DEVELOPS CONVECTION IN MIDDLE
TN AND THE PLATEAU ALONG AN OUTFLOW BOUNDARY. INSTABILITY APPEARS
GREATEST IN THAT AREA...SO WILL HAVE HIGHEST POPS WEST TODAY...BUT
STILL IN THE CHANCE RANGE EVERYWHERE. WILL CONTINUE WITH PERSISTENCE
FOR TEMPERATURES TODAY AND TONIGHT.
.LONG TERM (TUESDAY THROUGH SUNDAY)...
BERMUDA RIDGE WILL REMAIN OVER THE SOUTHEAST UNITED STATES THROUGH
MID-WEEK. GFS AND NAM SHOW PWS AND INSTABILITY INCREASING TO 1.4 TO
1.6 INCHES FOR TUESDAY AND WEDNESDAY..SO COVERAGE AND INTENSITY OF
STORMS WILL LIKELY INCREASE TO SCATTERED. FOR THURSDAY INTO NEXT
WEEKEND...RIDGING OVER THE SOUTHERN APPALACHIANS WILL WEAKEN
ALLOWING A SERIES OF UPPER SHORT- WAVES OVER THE GREAT LAKES INTO
THE NORTHEAST TO CARVE OUT A LONG- WAVE TROUGH OVER THE EASTERN
UNITED STATES.
LOOKING AT INSTABILITY AND UPPER DYNAMICS...BEST CHANCE OF MORE
WIDESPREAD STRONG TO SEVERE STORMS STILL POINT TO THURSDAY AND WILL
MENTION IN THE HWO. A COLD FRONT MOVING THROUGH SATURDAY WILL BRING
IN DRIER DEWPOINTS FOR SUNDAY.
AS FOR TEMPERATURES...GENERALLY FOLLOWED GFS NUMBERS CLOSELY..EXCEPT
FOR THE LATTER HALF OF THE WEEK. LOWER THICKNESS AND GREATER
COVERAGE OF CLOUDS AND CONVECTION DOES NOT WARRANT THE GFS HIGHS..SO
UNDER-CUT A DEGREE OR TWO.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 88 68 90 70 90 / 40 30 30 10 30
KNOXVILLE MCGHEE TYSON AIRPORT, TN 87 67 89 69 90 / 40 30 20 10 30
OAK RIDGE, TN 86 67 89 69 90 / 40 20 20 10 30
TRI CITIES AIRPORT, TN 87 64 88 63 89 / 30 20 30 10 30
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DGS/DH
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1128 PM CDT SUN JUN 23 2013
.AVIATION...
VFR EXPECTED TO DOMINATE...THOUGH WRF/NAM AND RAP SOLUTIONS
CONTINUE TO INDICATE NEAR-SATURATION OCCURRING BETWEEN 11Z-15Z AT
KLBB MONDAY MORNING NEAR H850 MB OR CLOSE TO 2000 FEET ABOVE THE
GROUND. SLIGHT UPGRADE IN WORDING TO A TEMPO SCATTERED LOW CLOUD
GROUP FOR KLBB DURING THIS PERIOD. FOR MONDAY AFTERNOON...LATEST
SOLUTIONS IN-LINE WITH OUR THINKING THAT THE SURFACE DRY-LINE SHOULD
NOT MAKE AS MUCH HEADWAY TO THE EAST...REMAINING WEST-NORTHWEST
OF KLBB. THUNDER CHANCES TOO LIMITED TO INCLUDE IN THIS TAF EDITION.
RMCQUEEN
&&
.PREV DISCUSSION... /ISSUED 924 PM CDT SUN JUN 23 2013/
UPDATE...
SHOWER CHANCES HAVE DWINDLED MOST OF THE AREA AS THE DRY-LINE
RETREATED RAPIDLY TO THE WEST THIS EVENING. RETAINED ISOLATED
MENTION ACROSS THE NORTHWEST...AND REMOVED THUNDER MENTION
ELSEWHERE. RMCQUEEN
PREV DISCUSSION... /ISSUED 717 PM CDT SUN JUN 23 2013/
UPDATE...
HIGH-BASED SHOWERS HAVE BEEN LATE TO DEVELOP...POSSIBLY DEVELOPED AS
DRY-LINE RETREATED INTO THE WESTERN SOUTH PLAINS. AS SUCH... SOME
DOUBT WHETHER THESE WEAK CELLS WILL BE ABLE TO SURVIVE AS THEY
TREK TO THE EAST-NORTHEAST. AND ALREADY WE ARE SEEING WEAKENING
TREND. RMCQUEEN
AVIATION...
ISOLATED HIGH-BASED SHOWERS HAVE DEVELOPED LATE ABOUT 20 MILES
WEST OF KLBB...AFTER WE ALREADY ISSUED THE 00Z TAF. WILL STUDY
CLOSE THE NEED FOR ADDING SHOWER OR THUNDER MENTION FOR KLBB. VFR
CONDITIONS OTHERWISE EXPECTED TO DOMINATE WITH SOUTHWEST FLOW
ALOFT AND A SURFACE TROUGH. STILL OUTSIDE RISK OF MVFR CEILINGS AT
KLBB EARLY MONDAY MORNING. RMCQUEEN
PREV DISCUSSION... /ISSUED 314 PM CDT SUN JUN 23 2013/
SHORT TERM...
LITTLE CHANGE IN THE LARGE SCALE PATTERN OR OVERALL THINKING WITH
REGARDS TO THE FORECAST TONIGHT INTO MONDAY...WITH BIGGEST CONCERN
REVOLVING AROUND STORM CHANCES THIS EVENING AND AGAIN LATE IN THE
DAY MONDAY. THE REGION CONTINUES TO RESIDE ON THE THE SOUTHERN
FRINGE OF SOUTHWESTERLY FLOW ALOFT WITH SEVERAL SUBTLE WEAKNESSES
MOVING THROUGH THE FLOW AND SKIRTING THE AREA PERHAPS PROVIDING WEAK
SUPPORT...THOUGH NWP IS MIXED WITH THIS SIGNAL. REGARDLESS..STRONG
HEATING IS TAKING PLACE WITH A SFC TROUGH STRETCHING FROM THE
CENTRAL TEXAS PANHANDLE INTO SOUTHEAST NEW MEXICO. AS OF 19Z...LIGHT
SOUTHWESTERLY WINDS AND DEWPOINTS FALLING INTO THE 40S AND 30S HAVE
INVADED THE WESTERN ZONES...SETTING UP A DIFFUSE DRYLINE...WITH
DEWPOINTS IN THE 50S ACROSS THE CENTRAL ZONES AND SOME LOWER 60S
HOLDING OFF THE CAPROCK. DEEP MIXING AND CONVERGENCE ALONG THE
DRYLINE MAY BE ENOUGH TO TRIGGER ISOLATED TO WIDELY SCATTERED
CONVECTION THROUGH EARLY THIS EVENING. IN ADDITION...THE TTU-WRF AND
HRRR SUGGEST OROGRAPHIC FORCING NEAR CAPROCK CANYONS MAY BE ENOUGH
TO INITIATE A STORM THERE. LATEST OBJECTIVE ANALYSIS SHOWS MLCAPES
AOA 2000 J/KG EAST OF THE DRYLINE...THOUGH WITH SOME INHIBITION YET
TO BE OVERCOME. DEEP LAYER SHEAR IS NOT OVERLY IMPRESSIVE...AROUND
25 KNOTS...PERHAPS PUSHING TOWARD 30 KNOTS BY THIS EVENING. THAT
SAID...IF STORMS DO DEVELOP...STRONG INSTABILITY COUPLED WITH THE
MODEST SHEAR WOULD SUPPORT A SEVERE THREAT. IN ADDITION...SLOW STORM
MOTIONS AND PWATS HOLDING IN EXCESS OF 1 INCH WILL SUPPORT A LOCALLY
HEAVY RAIN THREAT. ANY CONVECTION SHOULD FADE BY LATE THIS EVENING
AS THE LOWER ATMOSPHERE COOLS. HOWEVER...A SIMILAR SETUP WILL
PRESENT ITSELF AGAIN ON MONDAY THOUGH THE MOST RECENT SOLUTIONS DO
SUGGEST THE SFC TROUGH/DRYLINE WILL HALT FURTHER TO THE WEST NEAR
THE TX/NM LINE DURING THE AFTERNOON...KEEPING THE BEST STORM CHANCES
A LITTLE FURTHER WEST AS WELL.
BREEZY SOUTHERLY SFC WINDS OVERNIGHT /BENEATH A MODEST LLJ/ WILL
YIELD ANOTHER MILD NIGHT WITH LOWS BY MORNING RANGING FROM THE
MID-60S NORTHWEST TO MID-70S SOUTHEAST. THESE SOUTHERLY WINDS MAY
TRANSPORT SLIGHTLY IMPROVED LOW-LEVEL MOISTURE FROM WHAT WE SAW THIS
MORNING AND COULD EVEN RESULT IN A FEW LOW CLOUDS TOWARD MORNING.
ANOTHER HOT DAY WILL FOLLOW WITH HIGHS WELL INTO THE 90S.
TEMPERATURES MAY ACTUALLY STAY A FEW DEGREES COOLER ACROSS THE
WESTERN ZONES WHERE MOISTURE LEVELS SHOULD STAY HIGHER THAN TODAY.
ONGOING FORECAST HAD ALL OF THIS WELL IN HAND AND ONLY MINOR
ADJUSTMENTS WERE MADE TO THE FORECAST GRIDS.
LONG TERM...
UPPER RIDGE TO BEGIN BUILDING OVER THE ROCKIES TUESDAY WITH
INCREASING HEIGHTS AND MID LEVEL TEMPS LIKELY SHUTTING DOWN
DIURNAL PRECIP CHANCES...ALTHOUGH MODELS GIVING SOME INDICATION OF
ISOLATED HIGH-BASED STORMS DURING THE LATE AFTERNOON...A
POSSIBILITY TOO REMOTE ATTM TO INCREASE POPS TO SLIGHT CHANCE
CATEGORY. OTHER ISSUE IS PRECIP CHANCES FRIDAY THROUGH SUNDAY.
PREVIOUS MODEL RUNS INDICATED POTENTIAL FOR A COLD FRONT AND/OR
UPPER LEVEL DISTURBANCES TO MOVE SWD DOWN THE PLAINS ON THE EAST
SIDE OF THE UPPER RIDGE. THIS MORNING RUNS NOW PUSHING A PORTION
OF THE RIDGE EWD ALL THE WAY TOWARD THE LOWER MISSISSIPPI VALLEY
WHICH WOULD KEEP PRECIP MECHANISMS SHUT DOWN. WITH POPS ALREADY
BELOW MENTION DURING THAT PERIOD...WILL KEEP THEM THERE WITH JUST
SOME SLIGHT MASSAGING OF THOSE SUB-15 PCT POPS. THE POTENTIAL FOR
THE RIDGE TO BUILD EWD ALSO MEANS TEMPS WARMER THAN INDICATED IN
LAST SEVERAL FCST CYCLES AND WILL NUDGE UPWARDS BASICALLY KEEPING
HIGHS IN THE UPPER 90S ON THE CAPROCK AND NEAR 100 OFF THE CAP
THROUGH THE PERIOD WHILE OVERNIGHT LOWS GENERALLY MID 60S TO NEAR
70 ON THE CAP TO LOWER 70S OFF.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 66 95 65 99 66 / 20 20 20 10 10
TULIA 68 94 68 99 67 / 20 20 20 10 10
PLAINVIEW 70 95 69 99 69 / 20 20 20 10 10
LEVELLAND 67 95 68 99 69 / 20 20 20 10 10
LUBBOCK 70 95 71 99 72 / 20 20 20 10 10
DENVER CITY 68 95 69 99 69 / 20 20 20 10 10
BROWNFIELD 66 96 68 99 69 / 20 20 20 10 10
CHILDRESS 73 97 72 100 73 / 20 10 10 10 10
SPUR 71 96 71 99 72 / 10 10 10 10 10
ASPERMONT 75 98 73 99 74 / 10 10 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
05/99/05
AREA FORECAST DISCUSSION
NWS AMARILLO TX
1117 PM CDT SUN JUN 23 2013
.AVIATION...
06Z TAFS...BREEZY SOUTHERLY WINDS WILL BE THE RULE THROUGH THE NEXT
24 HOURS...WITH GUSTS AROUND 30 KTS EXPECTED LATE MONDAY MORNING INTO
MONDAY EVENING. A FEW SHOWERS ARE CURRENTLY SLOWLY MOVING TOWARD KAMA.
STILL PRETTY LOW CONFIDENCE THAT THEY/LL REACH THE TERMINAL BEFORE
DISSIPATING...AND EVEN IF THEY DO...IMPACTS WILL BE MINIMAL.
THUNDERSTORMS WILL ONCE AGAIN BE POSSIBLE LATE MONDAY AFTERNOON AND
EVENING...BUT CONFIDENCE IN THESE DIRECTLY IMPACTING A TERMINAL IS
TOO LOW TO MENTION ATTM. VFR CONDITIONS ANTICIPATED OUTSIDE OF ANY
THUNDERSTORMS.
NOTE TO USERS OF SURFACE OBSERVATION FROM RICK HUSBAND INTERNATIONAL
AIRPORT KAMA...COMMUNICATIONS PROBLEM WITH DATA LINE HAS PREVENTED
LONG-LINE DISSEMINATION OF SURFACE OBS. DATA COLLECTION PLATFORM AT
KAMA ASOS IS FUNCTIONING PROPERLY WITH CONTINUOUS MONITORING OF ALL
ELEMENTS BY AMARILLO NATIONAL WEATHER SERVICE FORECAST STAFF.
KB
&&
.PREV DISCUSSION... /ISSUED 952 PM CDT SUN JUN 23 2013/
UPDATE...
SHORTWAVE OVER SOUTHEASTERN AND EASTERN NEW MEXICO IN THE
SOUTHWESTERLY UPPER FLOW ACROSS THE PANHANDLES ALLOWING FOR
ADDITIONAL CONVECTION TO DEVELOP IN THE FAR EASTERN PLAINS OF NEW
MEXICO MOVING NORTHEAST INTO THE SOUTHWESTERN TEXAS PANHANDLE.
EXPANDED THE POPS THROUGH 06Z MONDAY A LITTLE FURTHER WESTWARD TO
ACCOUNT FOR THIS ROUND OF CONVECTION. SHORT RANGE MODELS IN GOOD
AGREEMENT SHOWING CONVECTION DEVELOPING ACROSS THE NORTHEAST TEXAS
AND EASTERN OKLAHOMA PANHANDLES TOWARD 09Z MONDAY. INTRODUCED THE 10
POP RULE OVER THE EASTERN SECTIONS OF THE PANHANDLES TO ACCOUNT FOR
THIS POSSIBILITY. DID NOTICE A LONE THUNDERSTORM ACROSS THE
SOUTHEASTERN TEXAS PANHANDLE LAST NIGHT AROUND 09Z SUNDAY OR SO...AND
CANNOT RULE OUT A SIMILAR SCENARIO ACROSS THE NORTHEASTERN OR EASTERN
SECTIONS OF THE FORECAST AREA LATER TONIGHT. LOW LEVEL JET ACROSS THE
EASTERN PANHANDLES LATE TONIGHT MAY ALSO HELP ADDITIONAL CONVECTION
TO DEVELOP LATE TONIGHT. ADJUSTED WIND AND SKY GRIDS TONIGHT...AND
ALSO POPULATED THE SMOKE MANAGEMENT GRIDS WITH THE LATEST NAM DATA
AND UPDATED THE LAL AND 20 FOOT WIND GRIDS. OTHERWISE...NO OTHER
CHANGES MADE TO PREVIOUS FORECAST AND GRIDS.
ALL PUBLIC AND FIRE WEATHER PRODUCTS HAVE BEEN UPDATED AND SENT.
SCHNEIDER
PREV DISCUSSION... /ISSUED 319 PM CDT SUN JUN 23 2013/
DISCUSSION...
JUST ONE MORE DAY OF THIS ACTIVE WEATHER PATTERN THAT THE REGION HAS
BEEN UNDER FOR OVER A WEEK NOW.
TONIGHT INTO TOMORROW...PRECIP CHANCES...THOUGH
MENTIONABLE...CONTINUE TO DECLINE AS DRY AIR ADVECTION CONTINUES.
PRECIPITABLE WATER VALUES ON THIS MORNINGS SOUNDING SHOW 0.79
INCHES...WHICH IS 92 PERCENT OF NORMAL...BUT A FAR CRY FROM THE 1
PLUS INCH VALUES WE/VE SEEN LATELY. IN ADDITION...IN THE WAKE OF THE
UPPER LEVEL TROUGH THAT MOVE THROUGH EARLY THIS MORNING...THERE IS
SOME UPPER LEVEL SHORT WAVE RIDGING OVER THE REGION. THIS SHOULD KEEP
COVERAGE OF STORMS VERY LIMITED. HOWEVER...IT IS INTERESTING TO NOTE
THAT THE RAP HIGH RESOLUTION MODEL SHOWS MORE COVERAGE THAN
YESTERDAY. IF ANY STORMS DEVELOP EITHER THIS AFTERNOON OR
TOMORROW...THE POTENTIAL REMAINS FOR MARGINALLY SEVERE HAIL AND DRY
AND HYBRID DOWNBURSTS LEADING TO STRONG WINDS.
TUESDAY THROUGH THURSDAY...INCREASING CONFIDENCE WITH VERY GOOD MODEL
AGREEMENT AND CONSISTENCY THAT THE RIDGE WILL BUILD OVER THE
SOUTHWEST THROUGH THIS PERIOD BRINGING A DRY AND HOT WEATHER PATTERN
THROUGH THE WEEK. STAYED CLOSE TO THE PREVIOUS FORECAST STILL
FAVORING HIGHER MAX TEMPS IN THE NORTHWESTERN PANHANDLES...WHICH
HAVE SEEN VERY LITTLE RAIN...WHILE KEEPING THE SOUTHEASTERN TX
PANHANDLE A FEW DEGREES LOWER DUE TO THE WET SOIL CONDITIONS.
HOWEVER...BY THE END OF THE WEEK...THESE DIFFERENCES MAY BE
NEGLIGIBLE AS THE SOILS DRY.
FRIDAY THROUGH SUNDAY...MODELS CONTINUED THE TREND OF SHOWING A
PERSISTENT RIDGE CONTINUING THROUGH THIS PERIOD. THE COLD FRONT WHICH
WAS SHOWN IN THE GFS TO ARRIVE ON FRIDAY...HAS ALL BUT DISAPPEARED IN
THE 12Z RUN. THUS...STAYED CLOSE TO THE PREVIOUS FORECAST WITH HOT
AND DRY WEATHER CONTINUING THROUGH THE WEEK.
JOHNSON
FIRE WEATHER...
ELEVATED TO NEAR CRITICAL FIRE WEATHER CONDITIONS MAY OCCUR TOMORROW
IN THE WESTERN OKLAHOMA AND FAR NORTHWESTERN TEXAS
PANHANDLES...THOUGH UNCERTAINTY REMAINS. MINIMUM RELATIVE HUMIDITY
VALUES SHOULD BE BELOW 15 PERCENT. HOWEVER...THOUGH WINDS ARE
EXPECTED TO BE NEAR 20 MPH...IT IS UNCERTAIN IF THE SURFACE TROUGH
WHICH RESULTED IN LIGHTER WINDS TODAY WILL BE A FACTOR TOMORROW AS
WELL. THOUGH MINIMUM RELATIVE HUMIDITY VALUES WILL DROP BELOW 20
THROUGH THE REMAINDER OF THE WEEK...AS WE SEE A DRIER PATTERN...NO
ADDITIONAL ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED
AT THIS TIME AS WINDS SHOULD BE LIGHT.
JOHNSON
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
08/11
AREA FORECAST DISCUSSION
NWS SPOKANE WA
224 AM PDT Mon Jun 24 2013
.SYNOPSIS...
A wet pattern will continue across the Inland Northwest through
mid week...with frequent showers and scattered thunderstorms
common. The weather the second half of the week will be
dramatically different as a warming and drying trend quickly
develops by late week. Summer-like temperatures will be possible
by the weekend.
&&
.DISCUSSION...
Today and tonight...Offshore low pressure buttressed against
interior ridging with an axis positioned over Eastern Montana
is allowing a moist and very dynamic southwest flow of moisture
and energy to continue to pass through Eastern Washington and
Northern Idaho. Negatively tilted shortwaves ejecting up through
this flow have enough energy to merit not only high pops and
moderate QPF for rain but also the mention of thunderstorms.
Recent HRRR model runs hint at once the elevated forced convective
showers and thunderstorms pass associated with the largest
baroclinic negatively tilted frontal zone passing through right
now there will be not so much a break in the activity but a
decreasing trend between the time when the elevated convection
either exits into Canada or erodes/weakens some along its back
trailing edges and the time near 18Z and beyond where surface
based convection is expected to start filling in the breaks.
Therefore the forecast will remain cluttered with moderate to high
pops, QPF, along with some mention of thunderstorms that decreases
substantially with loss of daytime heating allowing the surface
based convection to subside...especially noted after 6Z tonight.
/Pelatti
Tues through Fri Nt: This four-day period will be the transition
period characterized by wet weather Tue and Wed, then by a rapid
warming and drying trend Thurs and Fri. The primary concern will
be how much pcpn will fall in the mtn zones of Nrn Wa, the Id
Panhandle and the East Slopes of the Cascades. Three-day model
guidance QPF is depositing (through about Wed) big ranges anywhere
from 0.60-1.50 inches for these zones... with the SREF the least
and the GFS the highest amnts. A complicating factor in our pcpn
amnt fcst is the number of quick-moving waves that track across
the Pac Nw through mid-week. There are at least four subtle
features (depending on the model), all of which contain a decent
SW moisture tap, with pwat values averaging around one inch. The
latest TPW loop shows a nearly SW-to-NE plume of 200% of normal
values aimed at Nrn Calif. Our waves should be able to tap into at
least 100-150% values. Adding to the complexity of the wide-
ranging rainfall amnts is the element of instability, especially
late afternoon. This will be the dominating factor that will
produce wide-ranging rainfall amnts over very short distances.
Streams that will be affected most will be those across NE WA and
the N Id Panhandle...especially where the recent heavy pcpn fell the
last couple weeks...as well as the Stehekin River near the Cascade
crest.bz
Saturday through Monday...A ridge of high pressure will build north
near the Inland Northwest, bringing with it drying conditions and
above normal temperatures. The extended models are consistent in
building a ridge into the region, but how amplified the ridge is
and its placement are still in question. The difference is
forecasting temperatures in the 90s to temperatures a little
"cooler" in the 80s. Previous forecasts had lowered temperatures
a tad on Saturday and did not see any reason to deviate from this.
Until a little better consistency occurs, the forecast will trend
to the ridge building into eastern Washington and the Idaho
panhandle a little more each day, and thus warming temperatures a
few degrees each day. Precipitation chances remain near nil,
except for early Saturday where a lingering shower or thunderstorm
may occur over Idaho panhandle. ty
&&
.AVIATION...
06Z TAFS: Conditions will continue to deteriorate across the region
as a negatively tilted trough interacts with deep moisture over the
region to produce thickening and lowering ceilings with widespread
rain through about 16Z as the area of moisture moves from southwest to
northeast through the interior Pacific Northwest. Expect MVFR
ceilings at most TAF sites at times with improving conditions with
higher CIGS after 18Z Monday. TC
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 67 53 66 52 73 54 / 90 80 80 50 20 10
Coeur d`Alene 66 55 66 52 73 53 / 100 80 80 50 20 20
Pullman 66 52 66 51 74 52 / 70 60 70 50 20 10
Lewiston 71 57 74 57 80 58 / 70 60 60 60 30 20
Colville 71 54 70 51 75 52 / 100 70 80 60 20 20
Sandpoint 66 54 67 51 71 52 / 100 80 90 60 30 20
Kellogg 63 52 63 51 69 52 / 80 80 80 50 30 20
Moses Lake 74 58 69 56 80 58 / 50 30 50 20 20 10
Wenatchee 74 57 69 57 79 60 / 50 30 50 20 20 10
Omak 73 56 70 53 77 54 / 70 50 60 30 20 20
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
FORECAST DISCUSSION FOR ROUTINE MORNING FORECAST ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND TUESDAY
ISSUED AT 444 AM CDT MON JUN 24 2013
THE CONTINUING SAGA ON WHERE AND WHEN FOR CONVECTION CONTINUES THIS
MORNING. LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY HINT AT
WEAK BOUNDARY OVER NORTHEAST WI SEEN IN DEW POINTS. AREA OF
DISORGANIZED TSTMS MOVING NORTH THROUGH IA AND WESTERN IL.
STARTING TO SEE MORE MOVEMENT TO EAST OVER IL IN LATEST SCANS WHICH
WOULD GO WITH MODELS PROJECTION OF LLVL JET SHIFTING MORE TO THE
WEST AND WEAKENING BY 12Z.
HRRR SEEMS TO HAVE BEST HANDLE ON CURRENT TRENDS...SHOWING ONLY
SPOTTY CONVECTION OVER CWA TODAY MAINLY OVER THE SOUTH HALF.
ALL MODELS STILL SHOWING VARIETY OF SOLUTIONS IN QPF PATTERN
THROUGH THIS PERIOD. HAVE TRENDED TOWARD NAM TODAY GIVEN DRIER
AIR WORKING IN AS SEEN IN SIG DROP IN PWATS ON MSP SOUNDING LAST
EVENING. SFC BASED INSTABILITY STILL SIG 1-2K...THOUGH NOT SEEING
ANY REAL TRIGGER/LIFT TODAY. WENT WITH SLIGHTS FOR LATE DAY
CONVECTION SOUTH AND EAST ALONG LAKE BREEZE BOUNDARY.
FORCING AND MOISTURE WORKS BACK INTO THE AREA THIS EVENING WITH
STRENGTHENING LLVL FLOW POINTING INTO SOUTHWEST WI AFTER
06Z. ALSO SEEING SOME SUPPORT FROM RRQ OF JET MAX MOVING THROUGH
LAKE SUPERIOR REGION. WILL GO WITH INCREASING CHANCE POPS TONIGHT
HIGH CHANCE POPS TUE AS FGEN/ISENTROPIC LIFT MAXIMIZED OVER CWA
FROM 12Z TO 18Z TUES. CWA REMAINS IN SLIGHT RISK AREA ON TUE.
SHEAR BETTER SOUTH FOR SOME WIND CONCERNS. WBZERO HGTS RATHER
HIGH FOR LARGE HAIL. WITH PWATS RETURNING TO 1.5 TO 2 INCHES AGAIN
HEAVY RAIN MORE OF CONCERN.
.LONG TERM...TUESDAY NIGHT THROUGH SUNDAY
ISSUED AT 444 AM CDT MON JUN 24 2013
500MB RIDGE EXPECTED TO BUILD ACROSS THE WESTERN UNITED STATES
WHILE UPPER TROUGH DEEPENS AND POSSIBLY CLOSES OFF ACROSS THE
WESTERN GREAT LAKES BY THE END OF THE WORK WEEK INTO NEXT WEEKEND.
FORECAST ISSUES ALREADY AT THE START OF THE PERIOD TUESDAY NIGHT.
HAVE CONCERNS ON THE PLACEMENT OF CONVECTION TUESDAY EVENING ACROSS
NORTHERN WISCONSIN. BELIEF IS THAT THE AXIS OF HEAVIER PRECIPITATION
TOO FAR NORTH. THINK BAND WILL BE FURTHER SOUTH AS FIRST COMPLEX OF
STORMS LATE MONDAY NIGHT AND TUESDAY WILL PUSH AN OUTFLOW BOUNDARY
SOUTHWARD THAN WHAT THE MODELS SHOW...SIMILAR TOO WHAT HAPPENED A
FEW DAYS AGO. GFS QPF FIELD SEEMS REASONABLE BASED ON MY CURRENT
THINKING. THIS COULD AFFECT THE RAIN CHANCES ACROSS THE NORTH
TUESDAY EVENING. SOUTHERN SECTIONS OF THE FORECAST AREA WILL BE
CLOSE ENOUGH TO STILL WARRANT LIKELY CHANCES. 500MB TROUGH SWINGS
INTO THE AREA TOWARDS 12Z WEDNESDAY...WARRANTING LIKELY POPS EVEN
ACROSS THE NORTH. UPPER TROUGH WILL SWING ACROSS THE AREA ON
WEDNESDAY. RAISED POPS TO 50 TO 55 PERCENT...AND MAY BUMP THEM
UP A LITTLE MORE BEFORE FORECAST ISSUANCE. THE UPPER TROUGH
SHOULD SWING EAST INTO LOWER MICHIGAN WEDNESDAY NIGHT. THERE WILL
STILL BE SOME LINGERING EVENING SHOWERS AND A FEW STORMS. MID
LEVEL LAPSE RATES NOT IMPRESSIVE...THEREFORE ONLY EXPECTED ISOLATED
NATURE OF ANY THUNDERSTORMS WEDNESDAY EVENING.
NORTHWEST FLOW ALOFT WILL CONTINUE THURSDAY AND FRIDAY...ALTHOUGH
A DEEPER 500MB TROUGH WILL SWING ACROSS THE AREA FRIDAY AFTERNOON AND
FRIDAY NIGHT. WILL CONTINUE THE SMALL CHANCES FOR SHOWERS SATURDAY...
BUT NOT TOO OPTIMISTIC WE WOULD SEE THEM AT THIS TIME SINCE UPPER
TROUGH WILL WELL EAST OF THE AREA WITH BUILDING HEIGHTS. CANADIAN
HIGH PRESSURE WILL DOMINATE THE WEATHER PATTERN ON SUNDAY...ALTHOUGH
COULD NOT RULE OUT A FEW ISOLATED SHOWERS SUNDAY AFTERNOON.
FOR THE MOST PART...VERIFICATION DATA HAS SHOWN WE AND NUMERICAL
GUIDANCE HAS BEEN TOO WARM OF LATE. DID NUDGE TEMPERATURES DOWN A
DEGREE OR TWO MOST PERIODS. WILL NEED TO WATCH WEDNESDAY...IF IT
STAYS CLOUDY AND THERE IS A LOT OF RAIN AROUND DURING THE DAY...
TEMPERATURES COULD STAY IN THE 70S.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1122 PM CDT SUN JUN 23 2013
GETTING A HANDLE ON PCPN TRENDS HAS BEEN A TOUGH TASK OVER THE
PAST FEW DAYS...SO OVERALL CONFIDENCE REMAINS LOW. REGARDLESS...
CURRENT INDICATIONS ARE THAT THE REST OF TONIGHT AND MUCH OF
MONDAY SHOULD BE DRY. SOME DRIER AIR WILL CONTINUE TO OVERSPREAD
NORTHERN WI TONIGHT...AND REMAIN IN PLACE ON MONDAY. WILL STILL
NEED TO MONITOR FOR POSSIBLE CONVECTIVE DEVELOPMENT ALONG ANY
WEAK BOUNDARIES DURING THE AFTERNOON...BUT CONFIDENCE IS TOO LOW
TO MENTION IN THE TAFS. BEST ESTIMATE RIGHT NOW IS THAT SOME
CONVECTION WILL FIRE MONDAY NIGHT...AS A WEAK UPPER DISTURBANCE
TRACKS THROUGH THE AREA AND A SOUTHWESTERLY LOW-LEVEL JET
REDEVELOPS.
THERE IS SOME POTENTIAL FOR FOG LATE TONIGHT...ALTHOUGH WILL ONLY
MENTION MVFR VSBYS...EXCEPT AT RHI WHERE SOME IFR CONDITIONS MAY
OCCUR.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....TE
LONG TERM......ECKBERG
AVIATION.......KIECKBUSCH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
415 AM CDT MON JUN 24 2013
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 415 AM CDT MON JUN 24 2013
06Z DATA ANALYSIS HAD LOW PRESSURE OVER LK WINNIPEG AND OVER THE
OK/TX PANHANDLE AREA...WITH A WEAK RIDGE OF HIGH PRESSURE IN BETWEEN
ACROSS SD TO IA. FRONTAL BOUNDARY/TROUGH FROM THE TX/OK LOW WAS
ACROSS KS TO NORTHERN MO. WARM/MOISTURE ADVECTION/THETA-E
CONVERGENCE OVER THIS BOUNDARY FOCUSED FROM EASTERN CO TO SOUTHERN
IA...WHERE CONVECTION WAS FIRING EARLY THIS MORNING. THE FCST AREA
AND REST OF WI/MN GETTING A NEEDED BREAK FROM THE SHRA/TSRA SO FAR
SUNDAY THRU THIS MORNING...BEING NORTH/EAST OF THE SFC-700MB RIDGE
AXIS.
INITIALIZATIONS OF 24.00Z MODELS BETTER THAN THE PAST COUPLE 00Z
CYCLES...THIS EXCEPT FOR THE GFS TOO HIGH ON SFC DEW POINTS OVER
MUCH OF THE MID/UPPER MS VALLEY. EVEN WITH TIGHTER/BETTER
INITIALIZATIONS...SOLUTIONS CONTINUE TO HAVE MESO-SCALE DIFFERENCES
WHICH IMPACT THE SENSIBLE WEATHER IN THE SHORT TERM. DPROG/DT OF
500MB HGTS AT 24.00Z SHOWED THE MODEL RUNS OF 22.00Z AND 23.00Z
VERIFIED WELL ACROSS NOAM/EASTERN PAC...FAVORING STRONGER OF EARLIER
RUNS WITH THE TROUGH/ENERGY NEAR LK WINNIPEG AND THE TROUGHING OVER
CA. MODEL CONSENSUS REMAINS GOOD WITH THE LARGER SCALE FEATURES
TODAY THRU TUE BUT PLENTY OF DETAIL DIFFERENCES REMAIN WITH THE
WEAKER SHORTWAVES THRU THE SOUTHWEST FLOW OVER THE CENTRAL CONUS.
GENERAL TREND IS A LITTLE FLATTER WITH THE CENTRAL CONUS RIDGING AND
STRONGER WITH UNIDENTIFIABLE SHORTWAVE FEATURES. CHECK OF OBS VS.
MODEL DATA AT 06Z SHOWED ALL TO BE REASONABLE WITH THE SFC MASS
FIELDS OVER THE CENTRAL CONUS. PER WV IMAGERY MODELS LOOKED GOOD
WITH THE LARGER SHORTWAVES OVER NOAM...WHILE STRUGGLING WITH WHAT
LOOKED TO BE A WEAK SHORTWAVE AIDING THE NEB/CO/KS CONVECTION. AS
HAS BEEN THE CASE THE PAST FEW DAYS...MODELS HAVING DIFFICULTIES
WITH CONVECTION OVER THE CENTRAL CONUS. CLOSEST WITH THE 00-06Z
PRECIP LOOKED TO BE THE GFS AND THE HRRR WRF MODEL. NO ONE CLEAR
FAVORITE. WITH ALL THE MODEL SCENARIOS ON HOW CONVECTION PLAYS OUT
THE NEXT 48-72HRS AND MOST MODELS CONTINUING TO STRUGGLE WITH THAT
EARLY THIS MORNING...SHORT-TERM CONFIDENCE REMAINS BELOW AVERAGE.
FORECAST TODAY/TONIGHT HINGES ON WHERE THE KS/NORTHERN MO BOUNDARY
ENDS UP. MODEL CONSENSUS LIFTS THIS BOUNDARY...AND ITS FOCUS FOR
FORCING/LIFT/CONVECTION INITIATION...SLOWLY NORTH TODAY/TONIGHT...
TO SOUTHWEST MN TO EASTERN IA/NORTHWEST IL BY 12Z TUE. MOISTURE
TRANSPORT/THETA-E CONVERGENCE ON NOSE OF THE 850MB JET ALREADY
FIRING THE CONVECTION OVER IA...WITH THIS TRANSLATING EAST/NORTHEAST
TOWARD AND INTO THE SOUTHEAST END OF THE FCST AREA. WILL EXTEND THE
FLASH FLOOD WATCH FOR THE SOUTHEAST END OF THE FCST AREA THRU THE
MORNING.
LOW LEVEL MOISTURE TRANSPORT/THETA-E CONVERGENCE CONTINUES TO
INCREASE OVER THE FRONT AND TOWARD THE AREA TODAY AS LOW PRESSURE
LIFTS INTO NEB. GENERAL MODEL CONSENSUS FOR CONVECTION TO SLOWLY
BUILD WEST/SOUTH OF THE FCST AREA THIS MORNING THE LIFT INTO THE AREA
THIS AFTERNOON. PER THE HRRR...PART OF THIS IS THE COMPLEX MOVING
ACROSS NEB EARLY THIS MORNING. LEANING TOWARD THE HRRR WHICH HAS
BEEN DOING A DECENT JOB WITH THE CO/NEB CONVECTION AND THAT ACROSS
IA...THE NEB CONVECTION GROWS ONCE IT REACHES STRONGER/RICHER
MOISTURE TRANSPORT OVER EASTERN NEB/WESTERN IA. SOME FORM OF
CONVECTIVE COMPLEX THEN HEADS TOWARD THE FCST AREA FOR THE AFTERNOON.
LOW LEVEL THERMODYNAMIC FORCING STRENGTHENS INTO THE AREA TONIGHT
ALONG WITH THE MOISTURE TRANSPORT AS THE FRONT SLOWLY LIFTS NORTH.
RAISED SHRA/TSRA CHANCES INTO THE 60-70 PERCENT RANGE FOR TONIGHT
INTO TUE MORNING. ANY TSRA WILL REMAIN EFFICIENT RAIN MAKERS WITH PW
VALUES IN THE 1.5 TO 1.75 INCH RANGE...ML CAPES OF 2K-3K J/KG AND
WARM CLOUD DEPTHS OF 3.5 TO 4KM. WITH MANY AREAS WATERLOGGED AND
HAVING ONGOING FLOODING ISSUES...WILL EXPAND THE FLASH FLOOD WATCH
TO COVER ALL BUT CLARK/TAYLOR COUNTIES FOR THIS AFTERNOON THRU MID
MORNING TUE.
FORCING SIGNALS GET A LITTLE MORE MUDDIED TUE. THIS NOT UNEXPECTED
DUE TO POTENTIAL DIFFERENT OUTCOMES WITH CONVECTION OVER THE UPPER
MIDWEST TONIGHT. APPEARS THE FRONT WILL REMAIN SOUTH OF THE FCST
AREA WITH THE 925-850MB FLOW CONTINUING TO PUSH/LIFT MOISTURE
NORTHWARD OVER IT. CONTINUED 40-60 PERCENT SHRA/TSRA CHANCES OVER
MUCH OF THE FCST AREA TUE. MAY NEED TO EXTEND THE FLASH FLOOD WATCH
THRU TUE INTO TUE NIGHT...BUT WILL DEAL WITH THAT ONCE WE GET PAST
TONIGHT.
ON TOP OF THE HEAVY RAIN CONCERNS...A FEW OF THE TSRA COULD BE
SEVERE THIS AFTERNOON/EVENING AND AGAIN TUE INTO TUE EVENING DUE
TO THE STRONG INSTABILITY...INCREASE OF THE 0-6KM SHEAR AND
POTENTIAL FOR TSRA TO ORGANIZE INTO COMPLEXES WITH STRONG COLD
POOLS. SEE SWODY1 AND SWODY2 FOR MORE DETAILS.
USED A BLEND OF THE NUMERICAL TEMP GUIDANCE FOR HIGHS/LOWS FOR
TODAY THRU TUE.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 415 AM CDT MON JUN 24 2013
FOR TUE NIGHT THRU WED NIGHT MODELS SHOW THE REMNANTS OF THE
TROUGHING NOW OVER CA WILL LIFT INTO AND ACROSS THE UPPER MIDWEST.
TREND CONTINUES TO FAVOR STRONGER OF THE EARLIER RUNS. WITH THIS
BEING A LARGER SCALE FEATURE AND THE DECENT MODEL CONSISTENCY FCST
CONFIDENCE FOR THIS PERIOD IS AVERAGE.
AS THE STRONGER MID LEVEL TROUGH MOVES INTO THE UPPER MIDWEST TUE
NIGHT THE PLAINS SFC LOW MOVES INTO MN/WI. LOWER LEVEL THERMO
DYNAMIC FORCING/LIFT AND MOISTURE TRANSPORT REMAINS STRONG INTO THE
AREA AHEAD OF THESE FEATURES. WHERE THE FRONT AHEAD OF THE LOW FROM
TODAY/TUE ENDS UP WILL DETERMINE WHERE THE STRONGER LIFT WILL BE.
MODEL CONSENSUS HAS IT SOMEWHERE OVER THE FCST AREA TUE NIGHT...
THUS CARRIED HIGHEST SHRA/TSRA CHANCES IN THE 60-70 PERCENT RANGE
OVER THE NORTHEAST 2/3 OF THE FCST AREA. PW VALUES REMAIN IN THE 1.5
TO 1.75 INCH RANGE WITH ANY STORMS CAPABLE OF PRODUCING HEAVY RAINS.
AGAIN...WILL LIKELY NEED MORE FLASH FLOOD WATCHES FOR PORTIONS OF
THE AREA INTO TUE NIGHT WITH POTENTIAL FOR ANOTHER 0.5 TO 1.5
INCHES...LOCALLY MORE...OF RAIN.
ONCE THIS STRONGER MID LEVEL TROUGH PASSES TUE NIGHT/WED MORNING THE
FLOW PATTERN OVER NOAM BEGINS TO CHANGE WITH RIDGING BUILDING OVER
THE WESTERN CONUS AND INCREASING NORTHWEST FLOW ALOFT OVER THE
UPPER MIDWEST. DRIER AIR AND HIGH PRESSURE WILL SLOWLY SPREAD INTO
MN/IA/WI WED/WED NIGHT. SHRA/TSRA CHANCES WILL LINGER WED WITH THE
SFC LOW-MID LEVEL TROUGH OVER THE REGION. SHRA/TSRA CHANCES
DECREASE WED NIGHT AS HGTS RISE AND THE SFC-MID LEVEL LOW/TROUGH
MOVE EAST OF THE AREA.
DUE TO THE CONVECTION DETAIL UNCERTAINTIES...CONTINUED TO USE THE
MODEL/ENSEMBLE CONSENSUS FOR LOWS/HIGHS IN THE TUE NIGHT TO WED
NIGHT PERIOD.
ONCE AGAIN NOT A LOT OF TIME SPENT LOOKING AT THE DAY 4-7 PERIOD.
24.00Z MEDIUM RANGE MODELS MAINTAIN A GOOD CONSENSUS FOR THE
BUILDING WESTERN NOAM RIDGING AND EASTERN NOAM TROUGHING IN THE THU-
SUN PERIOD...WHICH PUTS THE REGION UNDER INCREASING NORTHWEST FLOW
ALOFT. THU-SUN SHAPING UP TO BE A DRIER PERIOD WITH TEMPERATURES
COOLING TO NEAR OR A BIT BELOW NORMAL. FCST CONFIDENCE FOR THIS
PERIOD LOOKS TO BE AVERAGE TO GOOD.
DRIER HIGH PRESSURE BUILDS IN FOR THU-SUN...BUT PLENTY OF RESIDUAL
LOW LEVEL MOISTURE AND MAXIMUM EVAPO-TRANSPIRATION FROM WELL WATERED
VEGETATION AND WET SOILS APPEAR TO REMAIN...ALONG WITH STEEP LOW/
MID LEVEL LAPSE RATES AND SHORTWAVES RIPPLING THRU THE NORTHWEST
FLOW ALOFT. THU-SUN TRENDING TO BE DRY DAYS BUT SOME SMALLER
MAINLY DIURNAL SHRA/TSRA CHANCES TO PERSIST...AIDED BY THE PASSING
SHORTWAVES FROM TIME TO TIME. MODEL/ENSEMBLE CONSENSUS FOR HIGHS/
LOWS IN THE DAY 4-7 PERIOD LOOK WELL TRENDED FOR NOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1141 PM CDT SUN JUN 23 2013
WATCHING A LINE OF CONVECTION ACROSS SOUTHERN IOWA THIS EVENING
WITH THE CONCERN OF WHETHER THIS WILL MOVE NORTHEAST INTO THE AREA.
THE 24.02Z HRRR AND ITS PREVIOUS RUNS HAVE BEEN DOING A DECENT JOB
HANDLING THIS FEATURE AND ATTEMPTS TO BRING IT NORTHEAST BUT
WEAKEN IT WITH TIME. RECENT RADAR TRENDS SUGGEST ONLY A VERY SLOW
NORTHEAST MOVEMENT WHILE THE CORFIDI VECTORS WOULD SUGGEST A MORE
EASTWARD MOVEMENT. FOR NOW...PLAN TO CONTINUE WITH A DRY FORECAST
AND ONLY SHOW SOME VFR CLOUDS FROM THIS SYSTEM GETTING INTO THE
AREA. VARIOUS SOLUTIONS ON HOW MONDAY PLAYS OUT. WITH THE MAIN
BOUNDARY NOW WELL SOUTH OF THE AREA...SEVERAL MODELS INDICATING
THE NEXT ROUND OF CONVECTION SHOULD DEVELOP AGAIN OVER SOUTHERN
IOWA AND REMAIN TO THE SOUTH OF THE AREA. MODELS ALSO SHOW
DIFFERENT IDEAS WITH THE ONGOING CONVECTION OVER COLORADO. THE
23.12Z GEM AND ECMWF BRING THIS NORTHEAST AND EAST INTO THE AREA
WITH THE MEAN FLOW WHILE THE HRRR TAKES IT MORE EAST ACROSS
NEBRASKA AND KANSAS RIDING THE CAPE GRADIENT WHILE FEEDING OFF
THE LOW LEVEL MOISTURE FIELD. WOULD TEND TO THINK THE HRRR IDEA
HAS A HIGHER PROBABILITY OF VERIFYING...BUT THERE IS A SHORT WAVE
TROUGH DRIVING THIS SYSTEM THAT SHOULD GET INTO THE AREA LATE
MONDAY AFTERNOON OR EVENING. WITH THE FORCING FROM THAT...CANNOT
TOTALLY RULE OUT SOME CONVECTION DEVELOPING BUT WITH LOW
CONFIDENCE HAVE ONLY INCLUDED A VCTS AT THIS TIME.
&&
.HYDROLOGY...
ISSUED AT 415 AM CDT MON JUN 24 2013
THE THREAT FOR HEAVY RAINS CONTINUES/RETURNS TODAY AS YET ANOTHER
LOW LIFTS INTO THE CENTRAL PLAINS AND MOISTURE TRANSPORT INCREASES
INTO THE AREA. A FRONT SLOWLY LIFTING NORTH FROM KS/NORTHERN MO WILL
BE THE FOCUS FOR LIFT AND GENERATING TSRA TODAY/TONIGHT/TUE. THIS
BOUNDARY EXPECTED TO REMAIN SOUTH OF THE AREA THRU TUE...WITH THE
ZONE OF STRONGER LIFT REMAINING CLOSE TO OR OVER THE FCST AREA.
THUNDERSTORMS WILL CONTINUE TO BE EFFICIENT RAIN PRODUCERS. RAINFALL
AMOUNTS THIS AFTERNOON AND TONIGHT COULD RANGE FROM 0.50 TO 1.50
INCHES...WITH LOCALLY HIGHER AMOUNTS POSSIBLE. SINCE MUCH OF THE
AREA HAS SEEN ANYWHERE FROM 2 TO 10 INCHES DURING THE LAST 3 TO 4
DAYS...IT WILL NOT TAKE MUCH RAIN TO PRODUCE MORE FLOODING PROBLEMS.
ADDITION FLASH FLOODING IS QUITE POSSIBLE ACROSS PARTS OF THE
FORECAST AREA TODAY THRU TUE NIGHT. HOWEVER THERE CONTINUES TO BE
MUCH UNCERTAINTY ON WHERE THIS RAIN MAY FALL. CONTINUED THE FLASH
FLOOD WATCH FOR THE SOUTHEAST END OF THE FCST AREA THIS MORNING
THEN ISSUED A BROADER FLASH FLOOD WATCH FOR ALL BUT CLARK/TAYLOR
COUNTIES THIS AFTERNOON THROUGH MID MORNING TUE. APPEARS ANOTHER
ROUND OF WIDESPREAD CONVECTION IS POSSIBLE TUE NIGHT/WED MORNING
AND ADDITIONAL FLASH FLOOD WATCHES ARE LIKELY FOR THOSE PERIODS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FLASH FLOOD WATCH FROM NOON CDT TODAY THROUGH TUESDAY MORNING
FOR WIZ032>034-041>044-053.
FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR WIZ054-055-061.
MN...FLASH FLOOD WATCH FROM NOON CDT TODAY THROUGH TUESDAY MORNING
FOR MNZ079-086>088-094>096.
IA...FLASH FLOOD WATCH FROM NOON CDT TODAY THROUGH TUESDAY MORNING
FOR IAZ008>010-018-019.
FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR IAZ011-029-030.
&&
$$
SHORT TERM...RRS
LONG TERM....RRS
AVIATION.....04
HYDROLOGY....RRS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1141 PM CDT SUN JUN 23 2013
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 344 PM CDT SUN JUN 23 2013
AT 3 PM...A LINE OF SHOWERS AND THUNDERSTORMS WAS MOVING ACROSS
NORTHERN ILLINOIS. MEANWHILE THERE WAS ANOTHER CONVERGENT BOUNDARY
ALONG THE MISSISSIPPI RIVER. BOTH THE 23.12Z ARW AND NMM DEVELOP A
LINE OF THE SHOWERS AND THUNDERSTORMS ALONG THE LATTER BOUNDARY
BETWEEN 23.21Z AND 24.00Z. HOWEVER THEY ALSO HAVE AROUND 3000 J/KG
OF SURFACE BASED CAPE AND THE SPC SURFACE BASED CAPE IS CURRENTLY
ONLY AROUND 500 J/KG...SO THINKING THAT THE AREA WILL REMAIN DRY
FOR LATE THIS AFTERNOON LIKE THE LAST 3 HOURLY RUNS OF THE HRRR
HAVE BEEN SHOWING.
FOR THIS EVENING...THE 23.12Z MESO /RAP...NMM...AND ARW/ AND
DETERMINISTIC MODELS SUGGEST THAT THE COMBINATION OF MODERATE 850
MB MOISTURE TRANSPORT AND 2 TO 3K MOST UNSTABLE CAPES WILL RESULT
IN THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS ACROSS NORTHEAST
IOWA...AND CENTRAL AND SOUTHWEST WISCONSIN. THE HRRR WAS
SUGGESTING A SIMILAR SCENARIO EARLIER THIS MORNING AND HAS SINCE
BACKED AWAY FROM THIS SOLUTION. WITH THERE BEING SUCH AGREEMENT IN
THE MODELS OPTED TO KEEP A 20 TO 60 PERCENT CHANCE GOING FOR THIS
AREA TONIGHT. WITH LITTLE OR NO PRECIPITATION EXPECTED ELSEWHERE
ACROSS THE FORECAST AREA...WILL DROP THE FLASH FLOOD WATCH
ACROSS SOUTHEAST MINNESOTA AND PARTS OF WEST CENTRAL WISCONSIN.
FOR OVERNIGHT...BOTH THE ECMWF AND NOW THE HRRR SHOW THAT A SHORT
WAVE CURRENTLY OVER THE TEXAS PANHANDLE WILL MOVE NORTHEAST INTO
NORTHEAST IOWA AND SOUTHWEST WISCONSIN. THE HRRR SHOWS AN AREA OF
SHOWERS AND THUNDERSTORMS SURGING NORTHWARD TOWARD THE FORECAST
AREA AFTER 07Z. DUE TO THIS KEPT...THE PRECIPITATION CHANCES IN
THE 20 TO 60 PERCENT RANGE. WITH PRECIPITABLE WATER VALUES AROUND
1.8 INCHES AND WARM CLOUD LAYER DEPTHS UP 4.5 KM...THESE
THUNDERSTORMS WILL BE VERY EFFICIENT RAIN PRODUCERS...THUS...KEPT
THE FLASH FLOOD WATCH UP NORTHEAST IOWA AND SOUTHWEST AND CENTRAL
WISCONSIN. THE ONLY QUESTION IN THE FORECAST IS WHETHER WE HAVE
THE PRECIPITATION CHANCES DECREASING TOO FAST TOWARD SUNRISE.
ON MONDAY...THERE IS UNCERTAINTY ON HOW LONG THE SHORT WAVE WILL
LINGER ACROSS SOUTHWEST WISCONSIN AND NORTHEAST IOWA. WITH MANY OF
THE MESO MODELS DRY FOR THE MORNING...DECIDED TO TREND THE
PRECIPITATION CHANCES TOWARD THE DRY SIDE. DURING THE
AFTERNOON...THERE IS UNCERTAINTY ON HOW FAST THE 850 MB MOISTURE
TRANSPORT WILL DEVELOP ACROSS THE AREA. THE NAM HAS IT DEVELOPING
DURING THE LATE AFTERNOON AND MANY OF THE OTHER MODELS SUGGEST
THAT IT MIGHT OCCUR ON MONDAY NIGHT. WITH THERE BEING VERY LITTLE
CONSISTENCY IN THE MODELS OVER THE PAST SEVERAL DAYS...DECIDED TO
COMPROMISE WITH 30 TO 40 PERCENT PRECIPITATION PROBABILITIES. LIKE
OVER THE WEEKEND...THE 0-6 KM SHEAR REMAINS LESS THAN 40 KNOTS.
HOWEVER THE 0-3KM CONTINUES ABOVE 30 KNOTS...THUS COULD SEE THE
POTENTIAL FOR SOME BOWING SEGMENTS AS THE THUNDERSTORMS BECOME
COLD POOL DOMINANT.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 344 PM CDT SUN JUN 23 2013
ON MONDAY NIGHT...THE MODELS CONTINUE TO SHOW THAT A MESOSCALE
CONVECTIVE COMPLEX WILL DEVELOP JUST WEST OF THE FORECAST AREA AND
THEN MOVE THROUGH THE FORECAST AREA DURING THE NIGHT. WITH STRONG
850 MB MOISTURE TRANSPORT AND ISENTROPIC LIFT INTO THE REGION...
PRECIPITABLE WATER VALUES RUNNING AROUND 2 INCHES...AND WARM CLOUD
DEPTHS EXCEEDING 4 KM...EXPECT AN AREA OF HEAVY RAIN /POTENTIALLY
3 TO 5 INCHES/ TO FALL ACROSS PARTS OF THE FORECAST AREA. MANY OF
THE MODELS ARE SUGGESTING ALONG AND NORTH OF THE INTERSTATE 90
CORRIDOR. HOWEVER WITH THE MODELS BEING A BIT TOO FAR NORTH
LATELY...THERE IS A POSSIBILITY THAT THE HEAVIEST PRECIPITATION
MAY FALL ACROSS NORTHEAST IOWA AND SOUTHWEST WISCONSIN. WILL
LIKELY HAVE TO ISSUE ANOTHER FLASH FLOOD WATCH FOR THIS TIME
PERIOD EITHER LATE TONIGHT OR ON MONDAY.
FROM TUESDAY AFTERNOON INTO TUESDAY NIGHT...THE MODELS SHOW YET
ANOTHER MESOSCALE CONVECTIVE COMPLEX MOVING THROUGH THE REGION.
WITH THE MODELS CONTINUING TO SHOW STRONG 850 MB MOISTURE
TRANSPORT AND ISENTROPIC LIFT INTO THE REGION... PRECIPITABLE
WATER VALUES RUNNING AROUND 2 INCHES...AND WARM CLOUD DEPTHS
EXCEEDING 4 KM...EXPECT AN AREA OF HEAVY RAIN /POTENTIALLY ANOTHER 3
TO 5 INCHES/ TO FALL ACROSS PARTS OF THE FORECAST AREA. AT THIS TIME...
IT LOOKS LIKE THE HEAVIEST RAIN WOULD FALL ALONG AND SOUTH OF THE
INTERSTATE 90 CORRIDOR.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1141 PM CDT SUN JUN 23 2013
WATCHING A LINE OF CONVECTION ACROSS SOUTHERN IOWA THIS EVENING
WITH THE CONCERN OF WHETHER THIS WILL MOVE NORTHEAST INTO THE AREA.
THE 24.02Z HRRR AND ITS PREVIOUS RUNS HAVE BEEN DOING A DECENT JOB
HANDLING THIS FEATURE AND ATTEMPTS TO BRING IT NORTHEAST BUT
WEAKEN IT WITH TIME. RECENT RADAR TRENDS SUGGEST ONLY A VERY SLOW
NORTHEAST MOVEMENT WHILE THE CORFIDI VECTORS WOULD SUGGEST A MORE
EASTWARD MOVEMENT. FOR NOW...PLAN TO CONTINUE WITH A DRY FORECAST
AND ONLY SHOW SOME VFR CLOUDS FROM THIS SYSTEM GETTING INTO THE
AREA. VARIOUS SOLUTIONS ON HOW MONDAY PLAYS OUT. WITH THE MAIN
BOUNDARY NOW WELL SOUTH OF THE AREA...SEVERAL MODELS INDICATING
THE NEXT ROUND OF CONVECTION SHOULD DEVELOP AGAIN OVER SOUTHERN
IOWA AND REMAIN TO THE SOUTH OF THE AREA. MODELS ALSO SHOW
DIFFERENT IDEAS WITH THE ONGOING CONVECTION OVER COLORADO. THE
23.12Z GEM AND ECMWF BRING THIS NORTHEAST AND EAST INTO THE AREA
WITH THE MEAN FLOW WHILE THE HRRR TAKES IT MORE EAST ACROSS
NEBRASKA AND KANSAS RIDING THE CAPE GRADIENT WHILE FEEDING OFF
THE LOW LEVEL MOISTURE FIELD. WOULD TEND TO THINK THE HRRR IDEA
HAS A HIGHER PROBABILITY OF VERIFYING...BUT THERE IS A SHORT WAVE
TROUGH DRIVING THIS SYSTEM THAT SHOULD GET INTO THE AREA LATE
MONDAY AFTERNOON OR EVENING. WITH THE FORCING FROM THAT...CANNOT
TOTALLY RULE OUT SOME CONVECTION DEVELOPING BUT WITH LOW
CONFIDENCE HAVE ONLY INCLUDED A VCTS AT THIS TIME.
&&
.HYDROLOGY...
ISSUED AT 344 PM CDT SUN JUN 23 2013
WITH SLIGHTLY DRIER AIR MOVING INTO SOUTHEAST MINNESOTA AND WEST-
CENTRAL WISCONSIN THIS AFTERNOON...THE THREAT FOR HEAVY RAIN HAS
GREATLY DIMINISHED ACROSS MUCH OF SOUTHEAST MINNESOTA AND PARTS OF
WEST CENTRAL WISCONSIN. AS A RESULT...DROPPED THE FLASH FLOOD
WATCH IN THESE AREAS. MEANWHILE IN SOUTHWEST AND CENTRAL WISCONSIN
AND NORTHEAST IOWA...THERE WILL BE THE POTENTIAL FOR THE
DEVELOPMENT OF THUNDERSTORMS ACROSS THESE AREAS FROM LATE EVENING
INTO THE OVERNIGHT. CONDITIONS CONTINUE TO BE FAVORABLE FOR THE
THUNDERSTORMS TO EFFICIENT RAIN PRODUCERS. RAINFALL AMOUNTS
TONIGHT COULD RANGE FROM 0.50 TO 1.50 INCHES. SINCE THESE AREAS
HAVE SEEN ANYWHERE FROM 6 TO 10 INCHES DURING THE LAST 3 DAYS...IT
WILL NOT TAKE MUCH WATER TO PRODUCE FLASH FLOODING.
ADDITION FLASH FLOODING LOOKS LIKELY ACROSS PARTS OF THE FORECAST
AREA ON MONDAY NIGHT AND FROM TUESDAY AFTERNOON INTO TUESDAY NIGHT.
EACH OF THESE EVENTS COULD PRODUCE 3 TO 5 INCHES OF RAIN ACROSS
THE AREA. HOWEVER THERE CONTINUES TO BE MUCH UNCERTAINTY ON WHERE
THIS RAIN MAY FALL. EXPECT ADDITIONAL FLASH FLOOD WATCHES TO BE
ISSUED FOR THESE TIME PERIODS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FLASH FLOOD WATCH UNTIL 7 AM CDT MONDAY FOR WIZ041>044-053>055-
061.
MN...FLASH FLOOD WATCH UNTIL 7 AM CDT MONDAY FOR MNZ096.
IA...FLASH FLOOD WATCH UNTIL 7 AM CDT MONDAY FOR IAZ008>011-018-019-
029-030.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...04
HYDROLOGY...BOYNE
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1133 PM CDT SUN JUN 23 2013
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.UPDATE...
ISSUED AT 943 PM CDT SUN JUN 23 2013
HAVE REMOVED PCPN CHANCES FOR THE REST OF TONIGHT. DAYTIME INSTABILITY
HAS WANED AND CONVERGENCE ALONG THE BOUNDARY THAT BISECTS THE CWA FROM
NE TO SW (SEE DEW POINT GRADIENT) HAS WEAKENED. 850 MB FLOW IS EXPECTED
TO CONTINUE TO VEER WEST OVERNIGHT...WHICH WILL BRING DRIER AIR INTO
THE REGION. PRECIPITABLE WATER ON THE MPX RAOB DROPPED FROM 1.72 INCH
AT 12Z TO 0.77 INCH AT 00Z.
DISTURBANCE OVER NORTHEAST COLORADO IS EXPECTED TO LIFT NE TOWARD WI
BY MONDAY EVENING. THE LLJ IS ALSO EXPECTED TO BACK SW AND INCREASE
UPSTREAM OF THE REGION...SO PCPN CHANCES SHOULD INCREASE AGAIN
TOMORROW NIGHT.
&&
.SHORT TERM...TONIGHT AND MONDAY
ISSUED AT 252 PM CDT SUN JUN 23 2013
THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A SURFACE
WARM FRONT HAS MOVED THROUGH MOST OF WISCONSIN EXCEPT FOR FAR
NORTHEAST WISCONSIN EARLY THIS AFTERNOON. SOME REMNANT STORMS FROM
AN EARLIER LINE OF CONVECTION ARE MOVING ACROSS SOUTHERN
WISCONSIN...BUT STARTING TO SEE SIGNS OF BEEFY CU DEVELOPING FARTHER
NORTH FROM WAUSHARA COUNTY TO THE WESTERN UPPER PENINSULA. THIS IS
IN A REGION OF BUILDING ML CAPES FROM 1000-1400 J/KG. STILL PLENTY
OF TIME FOR FURTHER DESTABILIZATION TO OCCUR...WITH LIFT VIA
SHORTWAVE OVER NORTHWEST WISCONSIN. AM STILL EXPECTING STORMS TO
FIRE THOUGH IT MAY STILL HAVE A COUPLE HOURS TO GO. ACTUAL FRONT
LIES ACROSS EASTERN MINNESOTA AND CLEARING SKIES ARE MOVING INTO
SOUTHWEST MINNESOTA. IMPACTS FROM CONVECTION ARE THE MAIN FORECAST
CONCERN IN THE SHORT TERM.
TONIGHT..SHORTWAVE OVER NORTHWEST WISCONSIN WILL LIFT NORTHEAST AND
CLEAR NORTHEAST WISCONSIN IN THE EVENING. FORCING ALONG THE TAIL OF
THIS VORT AND FURTHER DESTABILIZATION SHOULD ALLOW SCT STORMS TO
MOVE ACROSS NORTHEAST WISCONSIN IN THE EVENING. WINDS AT 700MB ARE
PRETTY STRONG AT 45 TO 50 KTS...SO ANY STORMS WILL HAVE POTENTIAL AT
CREATING DAMAGING WIND GUSTS AND SMALL HAIL. LOSS OF HEATING AND
EXITING OF THE TAIL OF THE VORT SHOULD LET THE CONVECTION DIMINISH
AND/OR EXIT BY MID TO LATE EVENING. ACTUAL SURFACE FRONT WILL DROP
INTO NORTH-CENTRAL WISCONSIN AFTER MIDNIGHT. CONVERGENCE ALONG THE
FRONT IS VERY WEAK AND THERE IS NO SUPPORT ALOFT...SO COULD SEE SOME
LOW CLOUDS ALONG THE FRONT...MUCH NOT MUCH ELSE. WILL END POPS FROM
NW TO SE AFTER MIDNIGHT. MUGGY LOWS IN THE MID TO UPPER 60S.
MONDAY...SURFACE FRONT WILL STALL ACROSS NORTHERN WISCONSIN IN THE
MORNING. PROGGED SOUNDINGS AND UPSTREAM SATELLITE IMAGERY SHOW
PLENTY OF DRY AIR THROUGH THE COLUMN AND PARTLY TO MOSTLY CLEAR
SKIES. NO CLEAR TRIGGERS UPSTREAM EITHER SO WILL GO WITH A DRY BUT
PARTLY CLOUDY START TO THE DAY. COME AFTERNOON...AN 86/69 PARCEL
OVER THE FOX VALLEY WILL RESULT IN 3000 J/KG OF ML CAPE AND VERY
LITTLE CIN. CONVECTIVE TEMPS ARE IN THE LOW 90S AND DO NOT SEE A
TRIGGER...BUT PERHAPS THE LAKE BREEZE CAN CREATE THE NECESSARY
CONVERGENCE FOR A STORM OR TWO TO POP. WILL KEEP A SLIGHT CHANCE OF
A STORM OVER CENTRAL AND NORTHEAST WISCONSIN WHERE INSTABILITY IS
MAXIMIZED. HIGHS MAINLY IN THE MID 80S.
.LONG TERM...MONDAY NIGHT THROUGH SUNDAY
ISSUED AT 252 PM CDT SUN JUN 23 2013
MEDIUM RANGE MODELS ARE IN GREATER DISAGREEMENT THAN
THE LAST FEW DAYS...ESPECIALLY WITH A POSSIBLE CONVECTIVE COMPLEX
LATE MONDAY NIGHT OR TUESDAY AND AGAIN WEDNESDAY NIGHT WITH THE
POSSIBLE FORMATION OF A CLOSED LOW OVER WISCONSIN OR UPPER
MICHIGAN. AS FAR AS LATE MONDAY NIGHT AND TUESDAY GOES IT LOOKS
LIKE THE GFS IS EXHIBITING SOME SORT OF CONVECTIVE FEEDBACK
PRODUCING A CLOSED UPPER LOW THAT MOVES ACROSS MINNESOTA AND
WISCONSIN PRODUCING CONSIDERABLE CONVECTION. THIS IS LIKELY
OVERDONE AND PREFER THE FLATTER AND SLOWER UPPER SYSTEM THAT SHOULD
BRING SHOWERS AND THUNDERSTORMS TUESDAY AFTERNOON AND EVENING.
THE GFS ALSO FORECASTS A CLOSED UPPER LOW WEDNESDAY NIGHT AND
THURSDAY OVER THE WESTERN GREAT LAKES WHICH SEEMS OVERDONE
CONSIDERING THE CURRENT PATTERN. CANNOT TOTALLY DISCOUNT THE GFS
AS IT HAS SOME SUPPORT FROM THE NAM BUT THE ECMWF IS MUCH FASTER
AND WEAKER. WARM AND HUMID WEATHER EXPECTED THROUGH THURSDAY.
AFTER THURSDAY THE MODELS DO AGREE THAT AN UPPER RIDGE
WILL DEVELOP OVER THE WESTERN UNITED STATES WITH CYCLONIC
NORTHWEST FLOW OVER WISCONSIN. THIS SHOULD BRING COOLER AND DRIER
AIR TO THE REGION BY FRIDAY AND SATURDAY. WHILE IT SHOULD BE
GENERALLY DRY FRIDAY AND SATURDAY THERE COULD BE SCATTERED DIURNAL
SHOWERS WITH COLD TEMPERATURES ALOFT.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1122 PM CDT SUN JUN 23 2013
GETTING A HANDLE ON PCPN TRENDS HAS BEEN A TOUGH TASK OVER THE
PAST FEW DAYS...SO OVERALL CONFIDENCE REMAINS LOW. REGARDLESS...
CURRENT INDICATIONS ARE THAT THE REST OF TONIGHT AND MUCH OF
MONDAY SHOULD BE DRY. SOME DRIER AIR WILL CONTINUE TO OVERSPREAD
NORTHERN WI TONIGHT...AND REMAIN IN PLACE ON MONDAY. WILL STILL
NEED TO MONITOR FOR POSSIBLE CONVECTIVE DEVELOPMENT ALONG ANY
WEAK BOUNDARIES DURING THE AFTERNOON...BUT CONFIDENCE IS TOO LOW
TO MENTION IN THE TAFS. BEST ESTIMATE RIGHT NOW IS THAT SOME
CONVECTION WILL FIRE MONDAY NIGHT...AS A WEAK UPPER DISTURBANCE
TRACKS THROUGH THE AREA AND A SOUTHWESTERLY LOW-LEVEL JET
REDEVELOPS.
THERE IS SOME POTENTIAL FOR FOG LATE TONIGHT...ALTHOUGH WILL ONLY
MENTION MVFR VSBYS...EXCEPT AT RHI WHERE SOME IFR CONDITIONS MAY
OCCUR.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE.........KIECKBUSCH
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......KIECKBUSCH
AREA FORECAST DISCUSSION
NWS ALBANY NY
1003 AM EDT MON JUN 24 2013
.SYNOPSIS...
VERY WARM AND HUMID CONDITIONS WILL CONTINUE EARLY THIS WEEK WITH
THE THREAT OF SHOWERS AND THUNDERSTORMS MAINLY DURING THE AFTERNOON
AND EVENING HOURS. STORMS WILL HAVE THE POTENTIAL TO PRODUCE LOCALLY
HEAVY RAINFALL. OUR NIGHTS WILL BE CONTINUE TO BE MUGGY WITH PATCHY
FOG. MORE PERSISTENT CHANCES FOR SHOWERS AND THUNDERSTORMS ARE
EXPECTED LATER IN THE WEEK INTO THE WEEKEND AS A SLOW MOVING LOW
PRESSURE SYSTEM IMPACTS THE REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 955 AM...ANOTHER HAZY...HOT AND HUMID DAY SHAPING UP. 12Z ALY
SOUNDING SHOWS PLENTY OF ENERGY FOR AFTERNOON THUNDERSTORMS. WATER
VAPOR LOOP SHOWS CLOSED LOW SPINNING OVER WESTERN PENNSYLVANIA.
THIS UPPER LEVEL LOW IS EXPECTED TO MOVE OVER THE SOUTHERN PART OF
THE ALBANY FORECAST AREA OVER THE NEXT 12-18 HOURS AND SHOULD BE A
FOCUS FOR STORMS. PWAT ON 12Z ALY SOUNDING WAS 1.77 INCHES SO
COPIOUS MOISTURE FOR HEAVY RAINERS. PIT 12Z SOUNDING...UNDER UPPER
LEVEL LOW...HAS STEEPER LAPSE RATES. 12Z HRRR SHOWING A MORE
WIDESPREAD THREAT OF AFTERNOON STORMS. WILL HAVE TO MONITOR FOR
LATER FLASH FLOOD WATCH IF LARGE AREA OF HEAVY RAIN DEVELOPS.
COULD BE AN EXCITING DAY...
PREVIOUS...
THE RIDGE WILL WEAKEN A TAD TODAY AS THE REMNANTS OF THE UPPER
LOW FROM OVER THE TENNESSEE VALLEY MOVES EASTWARD. THIS WILL BE
THE MAIN FEATURE TRIGGERING CONVECTION ACROSS THE AREA TODAY AND
IT WILL ACCOMPANY THE HEATING OF THE DAY. MODEL GUIDANCE SUGGESTS
CAPE VALUES OF PEAKING AT 1000-2000 J/KG WITH DEW POINTS IN THE
MID TO UPPER 60S. LAPSE RATE OF 6 TO 6.5 C/KM ARE EXPECTED THIS
AFTERNOON WITH THE GFS INDICATING 7 C/KM POSSIBLE. MEAN FLOW IS
RATHER WEAK AT 15 TO 20 KNOTS SO STORMS WILL MOVE RATHER SLOWLY
AND CONVECTION WILL BE LOOSELY ORGANIZED. THE STORM PREDICTION
CENTER HAS THE AREA/REGION IN THE GENERAL THUNDERSTORM OUTLOOK FOR
TODAY AND TONIGHT. FREEZING LEVEL IS HIGH JUST OVER 14000 FEET ON
THE 00Z/MON ALY SOUNDING...SO SOME STORMS WILL PRODUCE LOCALLY
HEAVY RAINFALL. THIS ALONG WITH THE RATHER SLOW MOVEMENT HAVE
ADDED ENHANCED WORDING OF HEAVY RAINFALL TO THE FORECAST AND WILL
KEEP MENTION IN THE HAZARDOUS WEATHER OUTLOOK. CONVECTION IS
EXPECTED TO DIMINISH THIS EVENING AS THE WEAKENING UPPER
LOW/TROUGH MOVES OFF TO THE EAST AND WITH THE LOSS OF DAYTIME
HEATING.
LOOKING AT TEMPERATURES IN THE 80S WITH AROUND 90 DEGREES UP THE
HUDSON VALLEY INTO CAPITAL DISTRICT. DEW POINTS WILL BE IN THE MID
TO UPPER 60S MAKING IT FELL EVEN HOTTER. HEAT INDICES SHOULD REACH
THE MID 90S UP THE HUDSON RIVER VALLEY.
ANOTHER MUGGY NIGHT WITH LOWS AND DEW POINTS IN THE 60S. WINDS WILL
BECOME LIGHT TO CALM WINDS. HAVE ADDED PATCHY FOG MAINLY IN THE
RIVER VALLEY LOCATIONS.
&&
.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
BY TUESDAY MORNING FLOW WILL BECOME NEARLY ZONAL ACROSS THE REGION.
A WEAKENING SURFACE LOW AND MID LEVEL SHORT WAVE TROUGH WILL MOVE
EASTWARD ACROSS SOUTHERN CANADA PASSING WELL TO OUR NORTH TUESDAY.
PLUS GUIDANCE INDICATES SMALL PIECES OF ENERGY SHOULD MOVE THROUGH
THE FLOW FARTHER SOUTH ACROSS OUR REGION.ALL THIS LEADS TO ANOTHER
ROUND OF CONVECTION MAINLY DURING THE AFTERNOON AND EVENING HOURS
TUESDAY WITH THE HEATING OF THE DAY. THE BETTER DYNAMICS AND SHEAR
WILL BE ACROSS NORTHERN NEW YORK INTO NORTHERN NEW ENGLAND AND THIS
IS WHERE THE STORM PREDICTION CENTER HAS GONE WITH A SLIGHT RISK FOR
SEVERE THUNDERSTORMS. FARTHER SOUTH ACROSS OUR FORECAST AREA MEAN
FLOW WILL STILL BE RATHER WEAK AROUND 20 KNOTS. IT WILL BE ANOTHER
HOT DAY SIMILAR TO MONDAY IN TEMPERATURES AND HEAT INDICES.
A WEAK FRONTAL BOUNDARY WILL BE BROUGHT SOUTHWARD INTO THE REGION
TUESDAY NIGHT...HOWEVER DUE TO THE FLOW ALOFT THE BOUNDARY WILL
STALL ACROSS THE REGION. A MORE VIGOROUS SHORT WAVE WILL MOVE INTO
THE LONGWAVE TROUGH OVER THE GREAT LAKES REGION WEDNESDAY AND
WEDNESDAY NIGHT AND HEIGHTS WILL BEGIN TO FALL. CHANCES FOR
CONVECTION WILL NOT BE LIMITED MAINLY TO THE AFTERNOON AND EVENING
HOURS THIS TIME. AS HEIGHTS CONTINUE TO FALL WILL HAVE LARGE SCALE
ASCENT THE BOUNDARY WILL BEGIN TO MOVE BACK NORTHWARD AS A WARM
FRONT.
PRECIPITABLE WATER VALUES WILL STILL BE HIGH SO LOCALLY HEAVY
RAINFALL IS EXPECTED WITH SOME STORMS...SO HAVE MENTIONED IN OUR
HAZARDOUS WEATHER OUTLOOK.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AN UNSETTLED AND WET EXTENDED FORECAST IS LIKELY ACROSS NY AND NEW
ENGLAND WITH PERSISTENT CHANCES OF SHOWERS AND THUNDERSTORMS...AS A
MID AND UPPER LEVEL TROUGH WILL INITIALLY IMPACT THE REGION TO CLOSE
THE WEEK...AND THEN IT MAY CLOSE OR CUT OFF NEAR THE GREAT LAKES
REGION AND SRN ONTARIO FOR THE WEEKEND.
THE LATEST GFS/ECMWF/CANADIAN GGEM/ENSEMBLE GUIDANCE AND HPC
GRAPHICS ARE IN PRETTY GOOD AGREEMENT FOR AN ACTIVE STRETCH OF
WEATHER. THEIR ARE SOME SUBTLE DIFFERENCES FOR THE TIMING OF THE
SHORT-WAVE IMPULSE ROTATING THROUGH THE UPPER LEVEL TROUGH...BUT ALL
AN ALL...IT IS EXTREMELY DIFFICULT TO FIND A SUSTAINED DRY STRETCH
OF WX TO CLOSE JUNE.
THU-FRI...A WAVE OF LOW PRESSURE APPROACHES THE FCST AREA FROM THE
GREAT LAKES REGION WITH SOME OVER RUNNING SHOWERS AND THUNDERSTORMS
AHEAD OF A WARM FRONT. THE WARM FRONT MAY BUST THROUGH PORTIONS OF
THE FCST AREA FOR A POTENTIAL OF STRONG THUNDERSTORMS...IF HEATING
IS REALIZED. THE DETAILS ARE NEBULOUS AND MURKY...SO WE WILL CALL
IT A CHANCE OF SHOWERS AND THUNDERSTORMS...THU INTO THU NIGHT. A
S/SW H850 LLJ OF 30-45 KTS WILL TRANSPORT IN SOME GULF
MOISTURE...AND PWATS WILL CONTINUE TO RUN ABOVE NORMAL. THE SFC LOW
BEGINS TO OCCLUDE AND CLOSE OFF JUST NORTHWEST OF LAKE ONTARIO AND
NRN NY ON FRI. THE GFS CONTINUES TO PAINT MODERATE AMOUNTS OF
INSTABILITY FOR THE POTENTIAL OF SHOWERS AND THUNDERSTORMS AGAIN.
THE SUBTROPICAL HIGH REMAINS ANCHORED DOWNSTREAM CONTINUING A DEEP
S/SW FETCH OF MOISTURE. THIS LONG DURATION STRETCH OF WX...BEGINS
TO MATERIALIZE INTO POTENTIALLY A CLASSIC GREAT LAKES CSTAR CUTOFF
LOW WARM SEASON EVENT. TEMPS LOOK TO RUN SLIGHTLY BELOW TO NEAR
NORMAL FOR THE THESE DAYS WITH HIGHS IN THE M70S TO L80S AND LOWS IN
THE U50S TO 60S.
SAT-MON...THE LONGWAVE TROUGH BEGINS TO AMPLIFY WITH THE EMBEDDED
500 HPA CLOSED CIRCULATIONS OVER THE CNTRL AND ERN GREAT LAKES. A
COLD FRONT BEGINS TO STALL OUT NEAR THE ERN CONUS SEABOARD.
MULTIPLE SHORT-WAVES LIFT NORTHWARD ON THE EAST SIDE OF TROUGH.
PERSISTENT BANDS OF SHOWERS AND THUNDERSTORMS TIMED TO THE DIURNAL
HEATING AND THE PROPAGATION OF THE IMPULSES ARE POSSIBLE FOR THE
WEEKEND INTO EARLY NEXT WEEK. THEIR IS A SMALL POSSIBILITY THAT
DRYING IN THE WAKE OF DISTURBANCES MAY PROMOTE MINI DRY STRETCHES.
AGAIN...THIS APPEARS TO FIT A GREAT LAKES WARM SEASON CSTAR
CLOSED/CUTOFF SCENARIO FOR AN EXTENDED PERIOD OF SHOWERS AND
THUNDERSTORMS. THE WEEKEND IS DOMINATED BY A POSITIVE TILT
SCENARIO...PERHAPS SHIFTING NEUTRAL BY EARLY NEXT WEEK. H850 TEMPS
CONTINUE TO BE IN THE +14C TO +16C RANGE WITH LIMITED HEATING EACH
DAY WITH A RESIDUAL COLD POOL ALOFT...AND THE ACTIVE S/SW FLOW.
EXPECT HIGHS TO CONTINUE IN THE 70S TO L80S WITH LOWS IN THE U50S TO
60S. TOO EARLY TO PINPOINT LOCATIONS...BUT SOME HYDRO PROBLEMS COULD
MATERIALIZE...IF LOCATIONS GET REPEATEDLY HIT BY BANDS OF SHOWERS
AND THUNDERSTORMS.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
HIGH PRESSURE NEAR THE MID ATLANTIC REGION WILL CONTINUE TO FUNNEL
NORTHWARD WARM AND HUMID AIR THE NEXT FEW DAYS. A WEAK MID LEVEL
DISTURBANCE MAY FOCUS SOME ISOLD-SCT SHOWERS AND THUNDERSTORMS THIS
AFTERNOON INTO THE EARLY EVENING.
VFR CONDITIONS ARE EXPECTED MOST OF THE DAY. THERE IS THE THREAT OF
SOME DIURNALLY TIMED SHOWERS AND THUNDERSTORMS. OUR CONFIDENCE
REMAINS AT ABOUT 25 TO 30 PERCENT FOR THUNDERSTORMS...SO A VCSH
GROUP HAS BEEN USED IN THE TAFS AT THIS TIME IN THE 18Z-00Z TIME
FRAME. IN THE WAKE OF THE DISTURBANCE THE SKIES WILL CLEAR AND SOME
PATCHY MIST/FOG MAY FORM AGAIN PRIOR OR JUST AFTER MIDNIGHT AT ALL
THE TAF SITES.
THE WINDS WILL INCREASE FROM THE SOUTH TO SOUTHWEST AT 5-10
KTS...AND VEER TO THE WEST TO SOUTHWEST AT AROUND 10 KTS WITH SOME
GUSTS CLOSE TO 20 KTS AT KPSF AND KALB. EXPECT THE WINDS TO BECOME
LIGHT TO CALM IN THE EARLY EVENING.
OUTLOOK...
TUE...MAINLY VFR. CHC -TSRA/-SHRA MAINLY DURING THE AFTN INTO THE
EVNG. MVFR-IFR FOG LATE AT NIGHT INTO EARLY IN THE MORNING.
WED...MAINLY VFR. SLIGHT CHC -TSRA/-SHRA.
THU-FRI...VFR/MVFR. CHC -TSRAS/-SHRAS.
&&
.FIRE WEATHER...
VERY WARM AND HUMID CONDITIONS WILL CONTINUE EARLY THIS WEEK WITH
THE THREAT OF SHOWERS AND THUNDERSTORMS MAINLY DURING THE AFTERNOON
AND EVENING HOURS. STORMS WILL HAVE THE POTENTIAL TO PRODUCE LOCALLY
HEAVY RAINFALL. OUR NIGHTS WILL BE CONTINUE TO BE MUGGY WITH PATCHY
FOG. MORE PERSISTENT CHANCES FOR SHOWERS AND THUNDERSTORMS ARE
EXPECTED LATER IN THE WEEK INTO THE WEEKEND AS A SLOW MOVING LOW
PRESSURE SYSTEM IMPACTS THE REGION.
&&
.HYDROLOGY...
INCREASING UNSETTLED WEATHER THIS WEEK. EARLY IN THE WEEK THE CHANCES
OF SHOWERS AND THUNDERSTORMS WILL BE MAINLY DURING THE AFTERNOON AND
EVENING HOURS. HOWEVER...PERSISTENT CHANCES OF SHOWERS AND
THUNDERSTORMS ARE EXPECTED FOR THE LATER PART OF THE WEEK INTO THE
WEEKEND AS A MID/UPPER LEVEL TROUGH IMPACTS THE REGION.
STORMS WILL HAVE THE POTENTIAL TO PRODUCE LOCALLY HEAVY RAINFALL ALL
WEEK WITH HIGH PRECIPITABLE WATER VALUES. EARLY IN THE WEEK FLOW ALOFT
WILL BE RATHER LIGHT SO STORMS WILL BE SLOWER MOVERS. FLOW IS
EXPECTED TO INCREASE LATER IN THE WEEK. PONDING OF WATER ON
ROADWAYS ALONG WITH MINOR FLOODING OF LOW LYING AND POOR DRAINAGE
AREAS WILL BE POSSIBLE. PLUS SOME SMALL STREAMS...CREEKS...AND
BROOKS MAY REACH BANKFULL OR EVEN FLOODING QUICKLY IN THE HEAVY
RAINFALL ASSOCIATED WITH THE THUNDERSTORMS ESPECIALLY IF STORMS
MOVE OVER THE SAME AREA REPEATEDLY.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...IAA
NEAR TERM...IAA/SND
SHORT TERM...IAA
LONG TERM...WASULA
AVIATION...WASULA
FIRE WEATHER...IAA
HYDROLOGY...IAA
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
959 AM EDT MON JUN 24 2013
.SYNOPSIS...
A BERMUDA HIGH PRESSURE SYSTEM WILL REMAIN OFF THE SOUTHEAST UNITED
STATES COAST FOR THIS UPCOMING WEEK. A BACKDOOR COLD FRONT WILL TRY
TO SINK SOUTHWARD INTO THE FORECAST AREA ON WEDNESDAY AND THURSDAY
BEFORE RETREATING NORTHWARD. A COLD FRONT WILL MOVE THROUGH THE
GREAT LAKES THURSDAY AND FRIDAY IS FORECAST TO APPROACH THE FORECAST
AREA SATURDAY AND MOVE THROUGH BY SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE UPPER LOW NOTED IN WV IMAGERY IS MOVING SLOWLY EWD THRU PA
THIS MORNING RESULTING IN SW FLOW ALOFT AS WELL AS AT THE SFC. 12Z
SOUNDINGS FROM IAD/APG SHOW DECENT CAPE IF CNVCTV TEMPS ARE
REACHED...AND ABOUT 1.5 IN PWAT WHICH IS SOMEWHAT ABOVE NORMAL FOR
THIS TIME OF YEAR. AMS NEAR THE CENTER OF THE UPPER LOW SEEMS TO
BE DRIER BUT COOLER ALOFT SO NOT SURE EXACTLY HOW THIS WILL PLAY
OUT FOR AFTN CONVECTION. BOTH THE RAP AND THE HRRR SHOW CNVTN
DEVELOPING AROUND 17Z. TODAYS TEMPS WERE TWEAKED UP A DEGREE OR
TWO BUT OTRW NO CHANGES TO THE CURRENT FCST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
THE UPPER LEVEL LOW WILL CONTINUE TO PROGRESS TOWARDS THE EAST
TONIGHT AS IT BECOMES LESS AND LESS DEFINED. THE LAST REMNANTS OF
THE EVENING CONVECTION SHOULD ALSO BE MOVING OUT OF THE REGION OR AT
LEAST OVER OUR NORTHERN ZONES BY LATE EVENING. HI-RES MODELS STILL
SHOW A FEW MID-LEVELS RIPPLES PULLING THROUGH IN THE MAINLY ZONAL
FLOW ALOFT SO A FEW PASSING SHOWERS LATE TONIGHT IS STILL POSSIBLE
ALTHOUGH THEY WILL BE MORE ISOLATED.
EXPECT MORE CLEARING TO TAKE PLACE WHEN COMPARED TO SUNDAY NIGHT
WHICH SHOULD ALLOW US TO RADIATE A BIT MORE. THE SURFACE FLOW SHOULD
BECOME LIGHT FROM THE SOUTHWEST...AGAIN, BUT THIS TIME WE COULD SEE
SLIGHTLY COOLER DEWPOINTS ADVECTED INTO THE REGION. ONCE AGAIN NOT
QUITE SURE THE EXTENT OF ANY FOG FORMATION AND QUITE FRANKLY THE
GUIDANCE IS NOT ALL THAT EXCITED EITHER...WILL KEEP IN PATCHY FOG
FOR TONIGHT.
TEMPERATURES TONIGHT SHOULD BE A COUPLE DEGREES COOLER THAN SUNDAY
NIGHT OUTSIDE THE URBAN HEAT ISLAND. USED A BLEND OF THE MET/MAV
WITH HEAVIER WEIGHTING TOWARDS THE COOLER MAV.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
SEVERAL ABOVE NORMAL TEMPERATURE DAYS IN STORE FOR THE AREA WITH
PLENTY OF HUMIDITY ALSO. THE BERMUDA HIGH PRESSURE AREA WILL SLOWLY
LOSE ITS INFLUENCE ON OUR WEATHER AS A DEEPENING TROUGH AND SFC LOW
MOVE INTO THE AREA FRI AND INTO THE WEEKEND. WE HAVE MOSTLY USED WPC
TEMPS/POPS FOR THE OVERNIGHT EXTENDED PACKAGE. THERE WILL BE DAILY
CHCS FOR SHOWERS/TSTMS DURING THE EXTENDED PERIOD. THE ADDED
CLOUDINESS AND SHOWERS WILL TEMPER THE MAGNITUDE OF THE ABOVE NORMAL
TEMPERATURES.
WE ARE FORECASTING HIGH TEMPERATURE READINGS TO REACH THE LOW 90S IN
MANY AREAS TUE-THU WITH PERHAPS A FEW MID 90S ON WED. HUMIDITY
LEVELS WILL BE MODERATE/HIGH WITH DEW POINTS IN THE MID 60S TO
AROUND 70S. THIS WILL PRODUCE APPARENT TEMPERATURES IN THE LOW/MID
90S ACROSS THE AREA. IT MAY BE NECESSARY TO ISSUE SOME HEAT RELATED
HEADLINES AS WE MOVE TOWARD THE MID-WEEK PERIOD. OVERNIGHT LOWS WILL
MOSTLY BE IN THE MID/UPPER 60S WITH SOME LOW 70S ACROSS METRO
PHILADELPHIA.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
A PLUME OF LOW CLDS WITH IFR CIGS FORMED EARLIER THIS MORNING OFF
THE NRN END OF CHES BAY AND AFFECTED BOTH PHL AND ILG FOR A COUPLE
OF HOURS. AS OF 1230Z THESE CLOUDS HAD DISSIPATED AND VFR CONDS
PREVAIL.
TODAY...VFR WITH SOUTHWEST WINDS. A WEAK SURFACE TROUGH WILL PUSH IN
FROM THE WEST THIS AFTERNOON AND COULD PROVIDE ENOUGH LIFT TO SPARK
WIDELY SCATTERED SHOWERS. DID NOT PLACE THESE IN THE TAFS AT THIS
TIME GIVEN LACK OF SPATIAL COVERAGE AND LOW CONFIDENCE ON INITIATION.
TONIGHT...THE SYSTEM THAT HAS BEEN KEEPING THE MID AND HIGH DECK
AROUND FOR THE PAST COUPLE OF DAYS IS FORECAST TO MOVE TO OUR
NORTHEAST TONIGHT. THIS WOULD ALLOW SKIES TO BECOME CLEARER THAN ON
PAST NIGHTS AND FOR BETTER RADIATIONAL COOLING TO TAKE PLACE. ANY
ADDED MOISTURE FROM THE SHOWERS WILL HELP FOR ANOTHER ROUND OF
GROUND FOG TO FORM. DO NOT HAVE THE CONFIDENCE YET TO PLACE IN THE
TAFS BUT WE WILL HAVE A BETTER CHANCE IF SKIES REALLY DO CLEAR OUT.
OUTLOOK...
TUE-WED...MOSTLY VFR WITH SHORT PERIODS OF SUB-VFR IN MORNING FOG
AND/OR SCT SHOWERS/TSTMS.
THU-FRI...VFR/MVFR IN MORE NUMEROUS SHOWERS/TSTMS.
&&
.MARINE...
ANOTHER TRANQUIL DAY IS EXPECTED ACROSS OUR WATERS WITH SOUTHWEST
WINDS AROUND 10-15KTS. STILL COULD SEE SOME GUSTS UPWARDS OF 20KTS
SEAS WILL CONTINUE TO BE AROUND 3 FEET TODAY AND THEN GRADUALLY
BUILD UPWARDS OF 4 FEET BY TONIGHT.
OUTLOOK...
SUB-SCA CONDITIONS MUCH OF THE WEEK WITH MOSTLY SW/S WINDS ON THE
WATERS. SCA WINDS/SEAS POSSIBLE FRI.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...O`HARA
NEAR TERM...AMC
SHORT TERM...HEAVENER
LONG TERM...O`HARA
AVIATION...AMC/HEAVENER/O`HARA
MARINE...HEAVENER/O`HARA
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
1052 AM EDT MON JUN 24 2013
.UPDATE...
500MB ANALYSIS SHOWS A TROUGH ACROSS WESTERN AL. THIS FEATURE HAS
SERVED TO FOCUS MOSTLY SHOWERS THIS MORNING ACROSS NORTH CENTRAL
AL...AND NOW NW GA. DO THINK ANY SCT PRECIP LATE THIS MORNING AND
EARLY AFTERNOON WILL BE CONCENTRATED CLOSEST TO THE TROUGH.
HOWEVER...FOR THE REMAINDER OF THE AFTERNOON...DO THINK PRECIP
WILL FOCUS JUST ALONG AND AHEAD OF THE SEA BREEZE ACROSS THE SE
CWFA. THE 12Z RUN OF THE HRRR SHOWS THIS FAIRLY WELL.
12Z SOUNDING ANALYSIS SHOWS A MOIST COLUMN UP THROUGH 750MB WITH
LIGHT SW FLOW IN THE BOUNDARY LAYER. PWATS ARE AROUND AN INCH AND
THREE QUARTERS...SO ANY THUNDERSTORMS THAT DEVELOP WILL BE CAPABLE
OF PRODUCING LOCALLY HEAVY DOWNPOURS. SURFACE WILL REMAIN PRETTY
UNSTABLE THROUGH THE DAY...SO SCT/NRMS TSTMS WILL BE POSSIBLE. A
FEW THUNDERSTORMS COULD BECOME STRONG AND PRODUCE PROLIFIC
LIGHTNING STRIKES...BUT THE POTENTIAL FOR SEVERE WEATHER IS RATHER
LOW.
&&
.PREV DISCUSSION... /ISSUED 734 AM EDT MON JUN 24 2013/
SHORT TERM /TODAY THROUGH TUESDAY/...
/ISSUED AT 402 AM EDT MON JUN 24 2013/
CURRENT CONVECTION OVER THE NORTHEAST MOUNTAINS RESPONDING TO A
MOIST UPSLOPE FLOW ALOFT. THIS WILL SLOWLY SHIFT INTO NORTH CAROLINA
HOWEVER THERE REMAINS ENOUGH OF A RISK TO KEEP LOW POPS GOING INTO
THE MID MORNING HOURS. ISOLATED SHOWERS HAVE ALSO DEVELOPED ACROSS
PARTS OF SOUTH AND EAST GA RESPONDING TO A WEAK SHORT WAVE IN THE
MID LEVELS. THIS KEEPS ENOUGH OF A RISK TO KEEP LOW POPS GOING INTO
THE MID MORNING HOURS AS WELL OVER PARTS OF CENTRAL GA. A SHORT WAVE
MOVING THROUGH THE MISSISSIPPI VALLEY WILL MOVE INTO THE CWA THIS
AFTERNOON. COMBINING THIS WITH AMPLE GULF AND ATLANTIC MOISTURE
SHOULD AID IN SCATTERED TO NUMEROUS THUNDERSTORMS THIS
AFTERNOON...MOST NUMEROUS ACROSS CENTRAL GA WHERE LIKELY POPS SEEM
IN ORDER. CONVECTION SHOULD DIMINISH AFTER SUNSET WITH SOME
LINGERING SHOWERS ACROSS THE NORTHEAST MOUNTAINS AND ALSO CENTRAL GA
INTO THE MORNING HOURS ON TUESDAY.
RISING H5 HEIGHTS WILL INCREASE THICKNESSES TODAY. THIS SHOULD
PRODUCE WARMER TEMPS TODAY. THE NAM IS A BIT COOLER AND HAVE OPTED
FOR THE WARMER GFS BOTH TODAY AND TUESDAY.
17
LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
/ISSUED AT 402 AM EDT MON JUN 24 2013/
DIURNAL CONVECTION EXPECTED EACH AFTERNOON AND EVENING THROUGH THE
WEEK. MODELS IN GOOD AGREEMENT WITH SURFACE RIDGE LOSING ITS GRIP
ON THE SOUTHEAST BY WEEKS END...AND UPPER LEVEL RIDGE BUILDING AND
REMAINING OVER THE WESTERN US AS LONG WAVE TROUGH SETS UP OVER THE
EAST COAST BY FRIDAY. WITH THE EASTERN EXTENT OF THE UPPER LEVEL
RIDGE MORE LIMITED THAN PREVIOUSLY EXPECTED...HAVE COOLED EXTENDED
HIGH TEMPERATURES A DEGREE OR TWO. STILL LOOKING FOR HIGHS IN THE
UPPER 80S AND LOW 90S.
HAVE INCREASED POPS SOMEWHAT FOR THE WEEKEND...AND EXPECT THIS
UPWARD TREND IN THE FORECAST TO CONTINUE IN THE COMING DAYS. ENHANCED
MOISTURE ACROSS THE REGION AS A RESULT OF THE UPPER LEVEL TROUGH
AND ASSOCIATED FRONTAL BOUNDARY SHOULD SUPPORT MORE SIGNIFICANT
COVERAGE OF PRECIP ACTIVITY. ANTICIPATE FRONTAL PASSAGE BY EARLY NEXT
WEEK...WITH DROP IN POPS AND SLIGHTLY COOLER TEMPERATURES IN STORE
AS A RESULT.
31
AVIATION...
12Z UPDATE...
WIDESPREAD IFR CIGS SHOULD LIFT TO MVFR BY MID MORNING AND VFR BY
NOON. EXPECT CONVECTION TO START AROUND NOON AND BECOME SCATTERED
ACROSS NORTH GA AND NUMEROUS ACROSS CENTRAL GA. THE CONVECTION
SHOULD DISSIPATE AFTER SUNSET. WINDS WILL BE SOUTHWEST THROUGH THE
FORECAST BUT WITH SPEEDS LESS THAN 10 KTS. IFR CIGS SHOULD DEVELOP
LATE TONIGHT ACROSS THE FORECAST AREA.
//ATL CONFIDENCE...12Z UPDATE...
MEDIUM ON CIG HGTS EARLY THIS MORNING.
HIGH ON OCCURRENCE OF CONVECTION THIS AFTERNOON...LOW ON IMPACTS TO
ATL.
17
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 87 69 89 70 / 40 40 30 20
ATLANTA 88 71 88 72 / 30 30 30 20
BLAIRSVILLE 83 63 84 65 / 40 40 30 20
CARTERSVILLE 87 68 88 70 / 30 30 30 20
COLUMBUS 91 73 92 73 / 60 60 30 20
GAINESVILLE 86 69 88 71 / 40 40 30 20
MACON 89 70 91 72 / 60 60 30 20
ROME 89 68 91 70 / 30 30 30 20
PEACHTREE CITY 88 68 90 70 / 40 40 30 20
VIDALIA 91 73 91 74 / 60 60 30 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...LISTEMAA
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1029 AM CDT MON JUN 24 2013
.DISCUSSION...
ISSUED 1028 AM CDT MON JUN 24 2013
HAVE MADE ONLY MINOR CHANGES TO GRIDS AND ZFP THIS MORNING TO
REFLECT THE CONTINUED POTENTIAL FOR THE REDEVELOPMENT OF SHOWERS
AND THUNDERSTORMS NORTH OF I-74. HRRR RUNS CONTINUE TO ALTERNATE
BETWEEN LOW POPS FOR THE REMAINDER OF THE DAY AND AN MCS ROLLING
ACROSS THE REGION. WITH SHORTWAVE NOW MOVING ACROSS IOWA COMBINING
WITH ANTICEDENT BOUNDARIES AND ABUNDANT PRECIP WATER...OVER 2
STANDARD DEVIATIONS ABOVE CLIMATOLOGY...HAVE INCREASED POPS NORTH
OF I-74 AND LOWERED HIGHS THERE. HAVE ALSO MADE SOME ADJUSTMENTS
TO REFLECT ONLY SCTATERED CLOUDS IN KIJX/KSPI AREA.
BARKER
&&
.AVIATION...
ISSUED 600 AM CDT MON JUN 24 2013
MAIN CONCERN WILL BE COVERAGE OF STORMS AGAIN TODAY AND THEIR
AFFECT ON CIGS AND VSBYS...OTHERWISE...WE EXPECT MAINLY VFR
CONDITIONS DURING THIS PERIOD (TIL 12Z TUE). MAIN BAND OF
STORMS HAS STAYED ROUGHLY NORTH OF A PIA TO BMI LINE THIS
MORNING. PIA EXPERIENCING SOME OCCASIONAL MVFR CIGS WITH
SOME OF THE HEAVIER SHOWERS THIS MORNING BUT AS THE AREA OF
RAIN GRADUALLY SHIFT TO THE NORTH AND EAST LATER IN THE
MORNING...EXPECT MAINLY VFR CONDITIONS TO PREVAIL AT PIA.
SCATTERED STORMS ARE AGAIN EXPECTED THIS AFTN INTO EARLY
THIS EVENING (ROUGHLY FROM 20Z-02Z) AS ANOTHER WEAK UPPER
LEVEL DISTURBANCE BRINGS THE ROUND OF STORMS THRU. COVERAGE
AT THIS POINT LOOKS TO SCATTERED TO INCLUDE A TEMPO GROUP
FOR ANY ONE SITE SO WILL CONTINUE WITH VCTS. SFC WINDS
WILL BE SOUTHERLY 12 TO 17 KTS TODAY AND AROUND 10 KTS TNT.
SMITH
&&
.PREV DISCUSSION...
ISSUED 240 AM CDT MON JUN 24 2013
ONGOING PARADE OF MCS ACTIVITY AND ASSOCIATED HEAVY RAINFALL WILL
CONTINUE TO BE A CONCERN FOR A COUPLE MORE DAYS. LATEST MCS
COVERED A GOOD PORTION OF IOWA...ALBEIT A BIT SMALLER THAN RECENT
NIGHTS...AND WAS BEING FED BY 40-45 KNOT LOW LEVEL JET. HAVE HAD
SOME STRONG THUNDERSTORMS SPREADING INTO THE NORTHWEST CWA OVER
THE LAST COUPLE HOURS ALONG A VERY SUBTLE SURFACE BOUNDARY.
MESOSCALE VORTEX FROM SUNDAY CONVECTION OVER THE SOUTHEAST CWA
STILL EVIDENT ON RADAR IMAGERY JUST EAST OF MOUNT VERNON.
SHORT TERM...TODAY THROUGH WEDNESDAY...
AS THE CASE HAS BEEN OVER THE LAST FEW DAYS...MODEL SOLUTIONS ARE
FAIRLY VARIED WITH MESOSCALE FEATURES NOT HANDLED ESPECIALLY WELL.
MCV IS ROTATING SOUTHEAST AND ACTIVITY WITH THIS FEATURE SHOULD
BE OUT OF OUR AREA BY SUNRISE...SO AM PLANNING TO KEEP THE FAR
SOUTHEAST DRY THIS MORNING. FOCUS DURING THE MORNING WILL MORE BE
ACROSS THE NORTHWEST AND ANY INFLUENCES FROM LEFTOVER BOUNDARIES
AND NEWER ONES FROM THE CURRENT CONVECTION. WILL HAVE THE HIGHEST
POPS DURING THE AFTERNOON AS MORE OF THE DAYTIME HEATING IS A
FACTOR. PRECIPITABLE WATER VALUES AROUND 1.7 TO 1.8 INCHES POINT
TO SOME HEAVY DOWNPOURS AGAIN...ALTHOUGH CENTRAL PARTS OF THE CWA
ARE MORE ABLE TO HANDLE THE HEAVY RAIN THAN THE SOUTHEAST...WHERE
1-HOUR FLASH FLOOD GUIDANCE IS ONLY AROUND A HALF INCH FROM
EFFINGHAM TO FLORA. MAIN SEVERE WEATHER RISK WILL BE WEST OF I-55
THIS AFTERNOON WHERE 0-6KM SHEAR EXPECTED TO INCREASE TO AROUND 40
KNOTS...ALTHOUGH A PULSE SEVERE STORM CANNOT BE RULED OUT
ELSEWHERE.
MAIN THUNDERSTORM FOCUS SHIFTS NORTHWARD LATE TONIGHT THROUGH
TUESDAY NIGHT. WITH MORE SUNSHINE...TUESDAY SHOULD BE THE HOTTEST
DAY OF THE WEEK WITH HEAT INDEX VALUES AT OR JUST ABOVE 100. HAVE
SOME CONCERN FOR SIMILAR VALUES WEDNESDAY...ALTHOUGH THIS WILL
DEPEND ON TIMING OF A FRONTAL PASSAGE AND ASSOCIATED
THUNDERSTORMS. MORE WIDESPREAD RISK OF SEVERE WEATHER EXPECTED ON
WEDNESDAY WHICH WOULD HELP TEMPER THE HIGHS SOMEWHAT. SOME
ADDITIONAL HEAVY RAIN LIKELY AGAIN ON WEDNESDAY WITH THE STORMS...
AS PWAT VALUES RISE BACK TO AROUND 1.8 INCHES.
LONG TERM...THURSDAY THROUGH SUNDAY...
UPPER RIDGING STILL PROGGED TO BUILD ACROSS THE WESTERN CONUS
DURING THE LATTER PART OF THE WEEK...WITH A SLOW COOLING TREND.
CYCLONIC FLOW OVER THE GREAT LAKES JUSTIFIES SOME LOW CHANCE POPS
OR SLIGHT CHANCES THURSDAY THROUGH FRIDAY...BUT THIS SHOULD FADE
AS HIGH PRESSURE BUILDS IN FROM THE NORTHWEST OVER THE WEEKEND.
GEELHART
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
629 AM CDT MON JUN 24 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 352 AM CDT MON JUN 24 2013
ANOTHER DIFFICULT FORECAST AS MESOSCALE FEATURES CONTINUE TO DEFINE
CONVECTIVE POTENTIAL...AND ARE DIFFICULT TO FORECAST MORE THAN A FEW
HOURS OUT. FOR TODAY...SOUNDINGS SUGGEST WAVE LIFTING OUT OF
OK/CTRL KS MAY SATURATE MID LEVELS ENOUGH TO SUPPORT SOME ISOLATED
CONVECTION THIS MORNING...AND WILL LEAVE AN ISOLATED POP TO REFLECT
THIS. HRRR MODEL...WHICH HAS PERFORMED WELL IN THE MORNING RUNS THIS
WEEK...DEPICTS CONVECTIVE COMPLEX OVER SC NEBRASKA SLIDING SLIGHTLY
TO THE SE AND BACK-BUILD INTO OUR FORECAST AREA LATER THIS
MORNING. FRONTAL BOUNDARY HAS SHIFTED FARTHER NORTHWARD AND SUSPECT
COMPLEX WILL STAY NORTH OF THE FA. ALSO SHOULD CONSIDER OUTFLOW
MOVING SE OUT OF IOWA CONVECTION AND WHERE THAT MAY END UP ON THE
KS/MO BORDER THIS AFTERNOON. AT THIS TIME LESS CINH AND BETTER
DYNAMICS COME TOGETHER NORTH OF THE AREA. HAVE STARTED WITH A SILENT
POP IN THE NE COUNTIES AND WILL MONITOR FOR DEVELOPMENT. BREEZY
SOUTHERLY WINDS WILL BE NEAR BUT GENERALLY BELOW WIND ADVISORY
CRITERIA AND WILL HOLD OFF FOR NOW. HIGHS TODAY IN THE 90S FOLLOWED
BY WARM OVERNIGHT LOWS IN THE MIDDLE 70S. WITH ANOTHER COMPLEX
MOVING NORTH OF THE FORECAST AREA LATE MONDAY INTO EARLY
TUESDAY...WILL CARRY A SLIGHT CHANCE POP ACROSS THE FAR NORTHERN
COUNTIES AS MAY SEE SOME LATE NIGHT COLD POOL LLJ INTERACTION. 67
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 352 AM CDT MON JUN 24 2013
MID RANGE AND EXTENDED FORECAST (TUESDAY THROUGH SUNDAY)...
WARM...MUGGY...AND DRY CONDITIONS EXPECTED TO PERSIST THROUGH MOST OF
THE MID RANGE AND EXTENDED PERIOD. FOR TUESDAY AND WEDNESDAY THE MID
LEVEL RIDGE GETS SOMEWHAT FLATTENED OUT AND DEAMPLIFIED AS THE HIGH
PRESSURE EXPANDS ACROSS THE SOUTHERN PLAINS. EVENTUALLY...BY MID
WEEK THE RIDGE WILL BECOME CENTERED OVER THE FOUR CORNERS REGION OF
THE US...AND WILL BECOME MOVE AMPLIFIED AS THE WEEK PROGRESSES. WITH
THE EASTERN EDGE OF THE HIGH PRESSURE DOME IN THE VICINITY OF
NORTHEAST KANSAS EXPECT SOME MID LEVEL NWLY FLOW TO REMAIN OVER THE
FORECAST AREA...WHICH WILL BRING THE POTENTIAL FOR MCS DEVELOPMENT
WITHIN THE FLOW. FOR NOW WILL KEEP A MOSTLY DRY FORECAST THROUGH THE
EXTENDED PERIOD...WITH THE LONE EXCEPTION OF THURSDAY NIGHT WHERE
THE ECMWF AND GFS AGREE ON THUNDERSTORMS DEVELOPING ALONG THE
PERIPHERY OF THE RIDGE AND DROPPING SOUTH/SOUTHEASTWARD OUT OF SE
NEBRASKA INTO NE KANSAS. GIVEN THE LACK OF ANY STRONG SIGNAL OF
OBVIOUS LIFTING MECHANISMS WILL ONLY GO WITH A SLIGHT CHANCE FOR
SHOWERS AND THUNDERSTORMS FOR THAT PERIOD. OTHERWISE...EXPECT A
RATHER WARM AND MUGGY PERIOD FOR TUES THROUGH THURS AS DAY TIME
HIGHS WILL GENERALLY REACH THE MID TO UPPER 90S...WITH HEAT INDEX
VALUES RANGING BETWEEN 100 AND 105 ACROSS MOST OF THE FORECAST AREA.
TEMPERATURES WILL COOL OFF A BIT FOR THE END OF THE WORK WEEK
THROUGH THE WEEKEND...AS A SURFACE HIGH BRINGS COOLER AIR INTO
NORTHEAST KANSAS. EXPECT TEMPS FOR FRIDAY THROUGH MONDAY TO BE IN
THE UPPER 80S TO PERHAPS THE MID 90S.
JL
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 626 AM CDT MON JUN 24 2013
EXPECT ANOTHER DAY WITH BREEZY SOUTH WINDS AND VCTS AT TIMES. HAVE
CARRIED 14Z AT MHK WITH 15Z AT TOP/FOE THEN ENDING LATER AFTERNOON
HOURS. KEPT WIND SPEEDS UP OVERNIGHT BUT WILL LIKELY NEED TO BRING
GUSTS OUT FOR A LATER PERIOD NEXT TAF ISSUANCE.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CRAVEN
LONG TERM...LEIGHTON
AVIATION...67
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1052 AM CDT MON JUN 24 2013
.MESOSCALE DISCUSSION...
ISSUED AT 1052 CDT MON JUN 24 2013
IR AND VISIBILE SATELLITE...AS WELL AS KVWX RADAR IMAGERY SUGGEST
A SMALL MESOSCALE VORTEX/SMALL SCALE TROUGH OVER SOUTHWEST INDIANA
NEAR KEVV BETWEEN 14Z-15Z. THIS FEATURE SHOULD ENGAGE ENOUGH LIFT
TO SUPPORT LOCALIZED UPDRAFTS CAPABLE OF PRODUCING SMALL HAIL
/POSSIBLY UP TO NICKLE SIZE/ ALONG AND TO THE EAST AND SOUTHEAST
OF THE VORTEX...LEADING INTO THE REMAINDER OF SOUTHWEST INDIANA
AND THE PENNYRILE REGION OF WEST KENTUCKY THIS MORNING.
ALSO...GIVEN THE SLOW MOVEMENT OF THIS FEATURE /LESS THAN 12
KNOTS/...AND PRECIPITABLE WATER VALUES AROUND TWO INCHES...WOULD
NOT BE SURPRISED TO SEE MINIMUM HOURLY RAINFALL VALUES BETWEEN
0.80 AND 1.10 INCHES IN THE HEAVIER RAINFALL CORES. WITH THIS IN
MIND...ADDED A MENTION OF SMALL HAIL/HEAVY RAIN TO THE HIGHEST POP
CATEGORY AREA FOR THE REMAINDER OF THE MORNING AND INTO THE EARLY
AFTERNOON MAINLY FOR HEAVY RAIN.
FURTHER TO THE WEST...THETA-E CONVERGENCE OVER SOUTHEAST MO SHOULD
CONTINUE TO EVOLVE IN THE WEEK CONVERGENT FLOW...JUST EAST OF THE
SOUTHEAST MO FOOTHILLS. SURFACE BASED INSTABILITY WILL REMAIN
HIGH...SO ANTICIPATE SOME ISOLATED DEVELOPMENT DURING THE
AFTERNOON OVER THE SOUTHEAST MISSOURI FOOTHILL INTO SOUTHWEST
ILLINOIS...MAINLY WEST OF INTERSTATE 57.
AM ALSO CONCERNED WITH DIFFERENTIAL HEATING AND AN INSTABILITY
GRADIENT WEST OF THE CURRENT CONVECTION THIS AFTERNOON...WITH WEAK
SURFACE CONVERGENCE LEADING TO AT LEAST SOME RENEWED...BUT BRIEF
DEVELOPMENT FROM THE LAND BETWEEN THE LAKES NORTHWARD TO THE
CONFLUENCE OF THE OHIO/WABASH RIVER...WEST OF THE CURRENT
CONVECTIVE ACTIVITY THIS MORNING. THE 3KM HRRR AND 4KM NAM-WRF
/NMM VERSION/ SEEM TO PICK UP ON THESE FEATURES AND SO TRIED TO
ADJUST ACCORDINGLY.
AN URBAN AND SMALL STREAM FLOOD ADVISORY WILL LIKELY BE POSTED FOR
THOSE COUNTIES ALONG AND EITHER SIDE OF THE MCV THIS MORNING AND
INTO THE EARLY AFTERNOON TO ACCOUNT FOR THE EFFICIENT RAINFALL
WITH THE STRONGER THUNDERSTORM CORES.
&&
.UPDATE...
ISSUED AT 643 AM CDT MON JUN 24 2013
UPDATED AVIATION DISCUSSION FOR 12Z TAFS.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 354 AM CDT MON JUN 24 2013
WEAK FLOW PATTERN WILL PERSIST ACROSS MUCH OF THE SOUTHERN AND
EASTERN U.S. THROUGH MID WEEK. AS A RESULT...MUCH OF THE LOCAL
WEATHER PATTERN WILL BE DRIVEN BY MESOSCALE INFLUENCES TYPICALLY
NOT HANDLED WELL BY OPERATIONAL MODELS. THE MAIN INFLUENCE TODAY
APPEARS TO BE AN MCV CURRENTLY DRIVING CONVECTIVE ACTIVITY OVER
SOUTHEAST ILLINOIS AND SOUTHWEST INDIANA. THE LATEST NAM AND HRW-
WRF RUNS APPEAR TO HAVE THE BEST HANDLE ON THIS FEATURE. FOLLOWING
THIS GUIDANCE...THE BEST POTENTIAL FOR SHOWERS AND THUNDERSTORMS
TODAY APPEARS TO BE OVER THE EASTERN HALF OF THE AREA...ESPECIALLY
SOUTHEAST ILLINOIS...SOUTHWEST INDIANA...AND THE PENNYRILE REGION
OF WESTERN KENTUCKY...AS THE MCV SLOWLY WORKS ITS WAY EAST ACROSS
THE AREA. WILL MAINTAIN THE POTENTIAL FOR ISOLATED MAINLY
DIURNALLY DRIVEN STORMS ELSEWHERE.
MOST MODELS ARE IN AGREEMENT THAT THE CHANCE FOR THUNDERSTORMS
SHOULD DROP OFF CONSIDERABLY TONIGHT THROUGH TUESDAY NIGHT WITH
NO SUBSTANTIAL FOCUSING MECHANISM. BETTER CHANCES FOR ISOLATED
ACTIVITY SHOULD BE CONFINED TO EASTERN AREAS AGAIN ON TUESDAY. IT
WILL REMAIN VERY WARM AND HUMID THROUGH THE NEAR TERM...WITH LOWS
IN THE LOWER 70S AND HIGHS IN THE LOWER 90S.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 354 AM CDT MON JUN 24 2013
THE MODELS CONTINUE TO ADVERTISE WHAT HAS BEEN FORECAST FOR A FEW
DAYS NOW. A SIGNIFICANT MID LEVEL HIGH CENTER OVER THE INTERMOUNTAIN
WEST WILL BECOME ESTABLISHED...WHILE A TROF OVER THE NE/ERN U.S.
MORPHS INTO A CLOSED LOW FEATURE AROUND THE GREAT LAKES REGION BY
THE WEEKEND ENHANCING THE TROF ALL THE WAY TO THE GULF COAST. THIS
WILL PLACE US IN AN UNSETTLED NW FLOW REGIME ALOFT WITH A SOMEWHAT
ILL DEFINED SURFACE PRESSURE PATTERN...THAT SHOULD CONTAIN MORE THAN
ONE SUBTLE WIND SHIFT UNTIL FRIDAY NIGHT WHEN THE FINAL ONE SHOULD
MOVE THROUGH ONCE THE TROF DEEPENS ENOUGH. PRECIP CHANCES NOT REAL
CLEAR CUT IN THIS FLOW PATTERN. HARD TO RULE OUT GIVEN THE TIME OF
YEAR AND UNSETTLED NATURE TO THE FLOW. GIVEN TIMING ISSUES AND MODEL
VARIANCE WHICH IS YIELDING LOW CONFIDENCE...WILL KEEP POPS IN CHECK
AND LOW FOR NOW. THERE IS STILL SOME PERSISTENCE WITH RESPECT TO
LATE WEDNESDAY INTO WEDNESDAY NIGHT...IN THAT THERE MAY BE A
CONVECTIVE SYSTEM THAT WILL AFFECT THE AREA. TEMPS ARE A BLEND OF
ECMWF LONG RANGE MOS / GFS MOS AND HPC GUIDANCE.
&&
.AVIATION...
ISSUED AT 643 AM CDT MON JUN 24 2013
A MESOSCALE VORTEX WILL CONTINUE TO TOUCH OFF SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS AT KEVV AND KOWB THROUGH MID MORNING...WITH
DRY CONDITIONS ELSEWHERE. ISOLATED TO WIDELY SCATTERED THUNDERSTORMS
MAY DEVELOP IN THE HEAT OF THE DAY JUST ABOUT ANYWHERE...BUT LOW
CONFIDENCE PRECLUDES MENTION IN TAFS AT THIS POINT. VFR CONDITIONS
WILL OTHERWISE PREVAIL. EXPECT SOUTHERLY WINDS AOB 10 KNOTS.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
MESOSCALE...SMITH
SHORT TERM...RJP
LONG TERM...CN
AVIATION...RJP
AREA FORECAST DISCUSSION
NWS GRAY ME
1205 PM EDT MON JUN 24 2013
.SYNOPSIS...
WARM AND MOIST AIR CONTINUES TO POOL ALONG AND SOUTH OF A
STATIONARY FRONT SITUATED TO OUR NORTH. SCATTERED SHOWERS AND
THUNDERSTORMS ARE EXPECTED EACH DAY THROUGH THE WEEK AS SEVERAL
DISTURBANCES CROSS THE REGION. A LARGE UPPER LEVEL TROUGH WILL
APPROACH FROM THE WEST LATE IN THE WEEK. THIS WILL ALLOW FOR
COOLER TEMPERATURES...BUT INCREASE THE CHANCE FOR SHOWERS ACROSS
THE REGION.
&&
.NEAR TERM /TODAY/...
NOON UPDATE...
HAVE MADE CHANGES TO THE POP STRUCTURE THROUGH THE AFTERNOON.
CUMULUS FIELD NOTED ON VISIBLE SATELLITE BUT NOTHING THAT IS READY
TO DEVELOP DEEP CONVECTION. SOME CONVECTION DEVELOPING OVER THE
ADIRONDACKS IN NEW YORK STATE WILL MOVE EAST THROUGH THE AFTERNOON.
ADDITIONAL DEVELOPMENT IS MOST LIKELY OVER THE HIGHER TERRAIN OF
NEW HAMPSHIRE AND NORTHWEST MAINE BUT COULD ALSO OCCUR ON THE
COASTAL PLAIN LATER IN THE AFTERNOON ONCE TEMPERATURES REACH THEIR
PEAK AND THE CAP BECOMES SUFFICIENTLY OVERCOME.
845 AM UPDATE...
HAVE UPDATED MOST OF THE GRIDDED FORECAST DATABASE THIS MORNING TO
BETTER REFLECT CURRENT FORECAST THINKING. LEFT POP STRUCTURE IN
PLACE FOR THIS AFTERNOON AS THERE WILL BE PLENTY OF CAPE AVAILABLE
WITH THE HEATING AND HUMIDITY THIS AFTERNOON. HOWEVER... UNSURE
THAT THERE WILL BE ENOUGH OF A FOCUSING MECHANISM TO HELP US
OVERCOME THE CAP. SEEMS LIKE THE BEST CHANCE WOULD BE TO GET SOME
STORMS GOING OVER THE MOUNTAINS. IF THIS DOES OCCUR... IT APPEARS
THAT HAIL AND WINDS WILL BE THE PRIMARY THREAT. WITH NEW DEW POINT
FORECAST... SOME AREAS OF SOUTHWEST MAINE SEE HEAT INDEX VALUES
REACH THE UPPER 90S TO NEAR 100 THIS AFTERNOON BUT NOT WIDESPREAD
ENOUGH FOR A HEAT ADVISORY.
630AM UPDATE...
UPDATE EARLY THIS MORNING TO LOWER THE CHANCES OF PRECIPITATION
OVER MUCH OF THE REGION THIS MORNING. THE EXCEPTION CONTINUES TO
BE THE NORTH AND MOUNTAINS WHERE OLD MCS CONTINUES TO DETERIORATE
AND MOVE EAST ACROSS MAINE. LATEST HRRR MODEL IS PICKING UP ON
THIS SYSTEM WELL THIS MORNING.
TIMING OF CONVECTIVE INITIATION TODAY APPEARS TO BE AROUND 16Z-
18Z OVER VERMONT. CELLS WILL ENTER NEW HAMPSHIRE BY AROUND 19Z OR 20Z
AND SPREAD QUICKLY TO THE EAST.
OTHERWISE...HAVE MADE SOME MINOR ADJUSTMENTS TO THE CLOUD...DEW
POINT AND MAX TEMPERATURE GRIDS BASED ON CURRENT TRENDS AND
OBSERVATIONS.
PREVIOUS DISCUSSION...
THE REMAINS OF AN MCS WILL CROSS NORTHERN SECTIONS EARLY THIS
MORNING...AS IT CONTINUES TO WEAKEN AS IT MOVES EAST. A DEVELOPING
WESTERLY FLOW ALOFT WILL ALLOW 850 MB TEMPERATURES TO CLIMB TO AT
OR ABOVE +16C DURING THE AFTERNOON HOURS. WITH AMPLE MIXING...WE
SHOULD EXPECT SOME LOWER 90S OVER SOUTHERN/CENTRAL NEW HAMPSHIRE
AND ADJACENT SECTIONS OF WESTERN MAINE. THERE WILL BE A SURFACE
TROUGH SITUATED NEAR AND ALONG THE COASTLINE...SO ONSHORE WINDS
WILL LIKELY KEEP THINGS COOLER OVER THE MIDCOAST REGION.
CAPES SOAR THIS AFTERNOON INTO THE 1500 J/KG RANGE OVER SOUTHERN
MAINE AND POSSIBLY SOUTHERN NEW HAMPSHIRE DURING THE AFTERNOON
HOURS TODAY AS A SHORT WAVE APPROACHES FROM THE WEST. LI VALUES
DROP SIGNIFICANTLY AS WELL. WE ARE NOT OUTLOOKED BY SPC
TODAY...HOWEVER FEEL COMPELLED TO AT LEAST MENTIONED GUSTY WINDS
AND SMALL HAIL IN THIS AREA.
PRECIPITABLE WATER VALUES WILL BE VERY HIGH TODAY...CLOSE TO 1.75
INCHES. WESTERLY FLOW SHOULD ALLOW FOR QUICK PROGRESSION OF
STORMS. NEVERTHELESS...ANY TRAINING ECHOES WILL NEED TO BE
MONITORED CLOSELY FOR THE THREAT OF HEAVY RAINFALL.
USED A BLEND OF MAV/MET MOS FOR DAYTIME MAX TEMPERATURES...WHICH
PLACES MANY AREAS IN THE LOWER 90S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
PATCHY FOG WILL REDEVELOP TONIGHT...ESPECIALLY IN THE VALLEY
LOCATIONS. THEREAFTER...SHOWERS AND THUNDERSTORMS WILL DEVELOP
DURING THE EARLY AFTERNOON HOURS ON TUESDAY AS VORT MAX APPROACHES
FROM THE NORTH. EXPECT SEVERAL STORMS TO PRODUCE DAMAGING WIND
GUSTS AS THE PRIMARY THREAT FOR SEVERE WEATHER AS THE WIND MAX
CROSSES THE REGION...BUT WE CANNOT RULE OUT THE POSSIBILITY OF
LARGE HAIL AS WELL. WILL HIGHLIGHT THIS IN THE HWO.
EXPECT MANY COMMUNITIES TO TOP OUT AT OR ABOVE 90 DEGREES ONCE
AGAIN OVER SOUTHERN/CENTRAL NEW HAMPSHIRE AND WESTERN MAINE.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
THRU THE OUTLOOK PERIOD THE EVOLUTION OF A LONG WAVE TROUGH WILL
BECOME ESTABLISHED OVER THE EASTERN GREAT LAKES AND EXTEND SOUTH
INTO THE OHIO VALLEY. THIS LONG WAVE TROUGH WILL BECOME THE MAIN
WEATHER PRODUCER FOR THE FORECAST PERIOD OF WEDNESDAY THROUGH
SUNDAY. THE DEVELOPING EASTERN LONG WAVE TROUGH WILL MEAN A
CONTINUED MOIST AND UNSTABLE SSW FLOW AT THE SURFACE AND ALOFT
THRU THE WEEK. SHOWERS/THUNDERSTORMS ARE EXPECTED THROUGHOUT THE
WEEK AND INTO THE WEEKEND. TEMPERATURES WILL BE COOLER THROUGH THE
WEEK DUE TO PLENTY OF CLOUDS AND THE MOIST SOUTHERLY FLOW. HIGH
TEMPERATURES WILL BE MOSTLY IN THE 70S BUT DEW POINTS WILL REMAIN
HIGH SO IT WILL BE MUGGY AS WELL.
USED A BLEND OF THE MAV/MET GUIDANCE FOR 4TH/5TH PERIODS AND THEN
THE ADJUSTED MEX TEMPERATURES FOR DAYS 4-7.
&&
.AVIATION /16Z MONDAY THROUGH FRIDAY/...
SHORT TERM...WEST WINDS TODAY MAY GUST INTO THE LOWER 20S. WINDS
AND THE POTENTIAL FOR HAIL IS POSSIBLE OVER SOUTHERN AREAS OF
MAINE THIS AFTERNOON AND OVER ALL AREAS ON TUESDAY.
LONG TERM...
VARIABLE CONDITIONS EXPECTED THRU THE OUTLOOK PERIOD. VFR
CONDITIONS ARE EXPECTED AT TIMES BUT WILL LOWER TO MVFR TO IFR
IN SCATTERED SHOWERS/THUNDERSTORMS THROUGHOUT THE MIDDLE TO END OF
THE WEEK.
&&
.MARINE...
SHORT TERM...
WINDS MAY BECOME GUSTY OVER THE OUTER WATERS TODAY...BUT MOST
LIKELY REMAINING BELOW SCA CRITERIA. SIMILAR CONDITIONS WILL
FOLLOW ON TUESDAY.
LONG TERM...
WINDS/SEAS WILL REMAIN BELOW SCA CONDITIONS THRU THURSDAY BUT MAY
INCREASE TO SCA CRITERIA ON FRIDAY DUE TO AN INCREASING SOUTHERLY
PRESSURE GRADIENT ALLOWING WINDS AND SEAS TO INCREASE.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
NEAR TERM UPDATE...KIMBLE
SHORT TERM...CANNON
LONG TERM...MARINE
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1021 AM EDT MON JUN 24 2013
.SYNOPSIS...
UNSETTLED CONDITIONS WITH SCATTERED SHOWERS AND THUNDERSTORMS WILL
PERSIST THROUGH MID WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
10AM UPDATE...
THE DECAYING MCS IS BRINGING SHOWERS TO HANCOCK AND WASHINGTON
COUNTIES AT THIS TIME AND WILL EXIT THE FORECAST AREA IN THE NEXT
FEW HOURS. SKIES WILL CLEAR FROM NW TO SE AS THE CLOUDS ASSOCIATED
WITH THE OLD MCS LEAVE THE STATE. THIS WILL PRODUCE HIGHS IN THE
MID TO UPPER 80S WITH UNCOMFORTABLE HUMIDITY. ADJUSTED HIGHS UP A FEW
DEGREES. DAYTIME HEATING WILL CREATE SOME DESTABILIZATION WITH THE
BEST CHANCES FOR STRONG STORMS IN THE REMOTE AREAS OF NORTHERN
SOMERSET...PISCATAQUIS AND AROOSTOOK COUNTIES THIS EVENING. STRONG
WIND GUSTS WOULD APPEAR TO BE THE BIGGEST THREAT. HOWEVER...WITH A
STRONG LLJ...HIGH PWATS AND WELL OVER 10K FT OF WARM CLOUD...HEAVY
RAIN IS ALSO A CONCERN.
UPDATE 0530L: DECAYING MCS HAS REACHED OUR FAR WRN ZONES ATTM.
THIS A LITTLE FASTER THAN ERLYR EXPECTED SO HAVE ADJUSTED POPS FOR
CURRENT AND EXPECTED TRENDS THRU THE AM HRS. REMAINDER OF THE FCST UNCHANGED...
DECAYING MCS OVR SRN QUEBEC ATTM ABOUT TO ENTER FAR WRN MAINE...
OTHERWISE...PARTLY TO MOSTLY CLOUDY SKIES ACROSS THE FA ATTM W/
SOME FOG ACROSS THE N. NOT MUCH CHANGE IN THE OVERALL PTRN ACROSS
OUR AREA LAST 24 HRS AT LEAST IN THE UPPER LEVELS OF THE ATMOS AS
BRISK WNW FLOW ALOFT PERSISTS W/ OCNL DISTURBANCES EMBEDDED IN
THIS FLOW. IN THE LOWER LEVELS - A VRY WARM AND HUMID SWRLY FLOW
IS NOW IN PLACE ACROSS THE ENTIRE REGION W/ TDS GENERALLY IN THE
LOWER TO MID 60S. THE DECAYING MCS IS SHOWN BY THE SHORTER TERM
MODELS SUCH AS THE RUC TO CONT TO MV ESEWRD AND HOLD TOGETHER ENUF
TO HAVE SOME IMPACT ON OUR WRN ZNS ERLY TDY THEN ACROSS OUR S
CENTRAL ZNS THRU THE AM HRS AND POPS ACROSS THESE AREAS WILL
REFLECT THIS. OTHERWISE...ANOTHER UPPER DISTURBANCE IS FCST TO
SLIDE ESEWRD ACROSS THE FA LATER TDY AND PROVIDE ANOTHER UPTICK IN
SHOWERS/TSTMS.
UNLIKE SUN...WHERE MOST ACTION WAS S OF THE AREA - APPEARS TDY
THAT THINGS HAVE SHIFTED A LITTLE FURTHER N W/ THE INTRUSION OF
THE WARMER AND MORE HUMID AIR. AS A RESULT...WILL CARRY MAINLY CHC
POPS ACROSS THE REMAINDER OF THE FA TDY INTO THIS EVE W/ ACTIVITY
EXPECTED TO AGAIN WEAKEN/DISSIPATE LATER THIS EVE AS THIS UPPER
DISTURBANCE MVS AWAY FROM THE REGION. THIS WILL SET THE STAGE FOR
MORE PATCHY FOG W/ THE FOG PROBABLY A LITTLE MORE WDSPRD THAN THIS
AM W/ THE HUMID AIRMASS PERSISTING. TEMPS TDY WILL BE A LITTLE
TRICKY... CLDS AND SHOWERS WILL NO DOUBT HAVE SOME IMPACT AND
PROBABLY KEEP MOST AREAS FROM REACHING FULL POTENTIAL TDY.
STILL...A LITTLE SUNSHINE FROM TIME TO TIME IS EXPECTED AND WILL
GO A LONG WAY IN HEATING THINGS UP SO WILL HANG ONTO HIGHS INTO
THE LOWER 80S N W/ MID TO PSBLY UPPER 80S CENTRAL AND INTERIOR
DOWNEAST...
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
PERIOD WILL BEGIN WITH A SURFACE HIGH SETUP IN THE ATLANTIC AND
BOUNDARY DRAPED JUST TO THE NORTH OF THE REGION. THE SURFACE HIGH
WILL CONTINUE TO PUMP WARM AND MOIST AIR INTO THE REGION. GUIDANCE
IS IN FAIR AGREEMENT WITH THE BOUNDARY AND SURFACE LOW BEGINNING
TO DROP SOUTH THROUGH THE DAY ON TUESDAY. THIS COMBINED WITH
BETTER UPPER LEVEL DYNAMICS WITH THE REGION LOCATED IN THE
FAVORABLE RIGHT ENTRANCE REGION OF UPPER LEVEL JET ENHANCING
DIVERGENCE ALOFT. ALSO WITH WARM AND MOIST UNSTABLE AIR IN PLACE
CAPE VALUES WILL BE GENERALLY BETWEEN 500 TO 1500 J/KG. THESE
DYNAMICS WILL MAKE IT POSSIBLE TO HAVE SOME MORE ENHANCED
THUNDERSTORM ACTIVITY TUESDAY AFTERNOON AND EVENING. RIGHT NOW
THINKING IS THERE WILL BE THE POTENTIAL FOR SMALL HAIL AND GUSTY
WINDS BUT THIS MAY NEED TO BE ENHANCED FURTHER IF DYNAMICS
CONTINUE TO COME TOGETHER. BEST CHANCES STILL LOOK TO BE ACROSS
THE NORTHERN AND CENTRAL PORTIONS OF THE REGION WHERE BEST
SUPPORTING DYNAMICS ARE PRESENT.
THERE IS SOME MODEL DIVERGENCE FOR WEDNESDAY WITH THE MOST OF
GUIDANCE WANTING TO KEEP THE LOW PRESSURE ACROSS THE REGION WHILE
THE 23/12Z ECMWF WANTS TO KEEP IT DRIER. RIGHT NOW WILL KEEP
DECENT CONSISTENCY WITH PREVIOUS FORECAST WITH MORE SHOWERY TYPE
ACTIVITY. TEMPERATURES FOR WEDNESDAY LOOK TO BE COOLER ALTHOUGH
THIS WILL BE HIGHLY DEPENDENT ON CLOUD COVER.&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
THE GUIDANCE IS STILL A BIT DIVERGENT IN THE BEGINNING OF THE LONG
TERM PERIOD. THE 24/00Z GFS/GEM WANTS TO HOLD ON TO THE BOUNDARY
AND SURFACE LOW A BIT LONGER THAN THE 23/12Z ECMWF FOR WEDNESDAY
NIGHT. THEN WE WILL SEE ANOTHER STRONG UPPER LEVEL DISTURBANCE
ACROSS THE GREAT LAKES CONTINUE TO PROGRESS EAST. ALL THE LONG
RANGE GUIDANCE INDICATES THIS MOVING EAST BUT WITH SLIGHT DIFFERENCES
IN TIMING. GENERALLY IT LOOKS LIKE THIS SYSTEM WILL BEGIN
PROGRESSING INTO THE REGION THURSDAY AFTERNOON. RIGHT NOW THE
GUIDANCE ALSO WANTS INDICATE THIS UPPER LEVEL LOW BECOMING QUASI-
STATIONARY GENERALLY ACROSS THE GREAT LAKES AND OHIO VALLEY. THIS
WOULD KEEP THE REGION IN A ACTIVE PATTERN THROUGH MUCH OF THE LONG
TERM PERIOD. THIS QUASI-STATIONARY TROUGH SETUP IS ALSO GENERALLY
SUPPORTED BY THE 23/12Z GFS/ECMWF RESPECTIVE ENSEMBLE MEAN. HIGH
AND LOW TEMPERATURES FOR THE PERIOD WILL GENERALLY BE NEAR NORMAL.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
NEAR TERM: VRBL CONDS ACROSS THE AREA THIS AM W/ SOME IFR IN FOG
ACROSS THE N TO VFR CONDS ACROSS THE S. EXPECT FOG TO DISSIPATE
ERLY THIS AM W/ PREDOM VFR CONDS TDY EXPECT OCNL MVFR TO BRIEF IFR
PSBL IN ANY SHOWERS/TSTMS. FOG WILL AGAIN BE A THREAT TNGT ALONG
W/ A CONTD CHC OF SHOWERS AND PSBL THUNDER...
SHORT TERM: MOST SITES LOOK TO STAY VFR THROUGH THE PERIOD WITH
THE EXCEPTION OF THOSE SITES THAT RECEIVE SHOWER AND THUNDERSTORM
ACTIVITY. THIS WILL BE MORE LIKELY FOR THE NORTHERN SITES.
&&
.MARINE...
NEAR TERM: WINDS/SEAS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT
ADVISORY LEVELS THRU TONIGHT. VISIBILITIES COULD BE REDUCED IN PATCHY
FOG TODAY AND IN MORE WDSPRD AREAS OF FOG TNGT.
SHORT TERM: MARINE: NO HEADLINES EXPECTED AT THIS TIME WITH SEAS
GENERALLY STAYING 2 TO 4 FT AND WINDS 10 TO 15 KT. VISIBILITIES
COULD BE REDUCED WITH SHOWERS.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...KHW/MCW
SHORT TERM...JORDAN
LONG TERM...JORDAN
AVIATION...KHW/MCW/JORDAN
MARINE...KHW/MCW/JORDAN
AREA FORECAST DISCUSSION
NWS GRAY ME
852 AM EDT MON JUN 24 2013
.SYNOPSIS...
WARM AND MOIST AIR CONTINUES TO POOL ALONG AND SOUTH OF A
STATIONARY FRONT SITUATED TO OUR NORTH. SCATTERED SHOWERS AND
THUNDERSTORMS ARE EXPECTED EACH DAY THROUGH THE WEEK AS SEVERAL
DISTURBANCES CROSS THE REGION. A LARGE UPPER LEVEL TROUGH WILL
APPROACH FROM THE WEST LATE IN THE WEEK. THIS WILL ALLOW FOR
COOLER TEMPERATURES...BUT INCREASE THE CHANCE FOR SHOWERS ACROSS
THE REGION.
&&
.NEAR TERM /TODAY/...
845 AM UPDATE...
HAVE UPDATED MOST OF THE GRIDDED FORECAST DATABASE THIS MORNING TO
BETTER REFLECT CURRENT FORECAST THINKING. LEFT POP STRUCTURE IN
PLACE FOR THIS AFTERNOON AS THERE WILL BE PLENTY OF CAPE AVAILABLE
WITH THE HEATING AND HUMIDITY THIS AFTERNOON. HOWEVER... UNSURE
THAT THERE WILL BE ENOUGH OF A FOCUSING MECHANISM TO HELP US
OVERCOME THE CAP. SEEMS LIKE THE BEST CHANCE WOULD BE TO GET SOME
STORMS GOING OVER THE MOUNTAINS. IF THIS DOES OCCUR... IT APPEARS
THAT HAIL AND WINDS WILL BE THE PRIMARY THREAT. WITH NEW DEW POINT
FORECAST... SOME AREAS OF SOUTHWEST MAINE SEE HEAT INDEX VALUES
REACH THE UPPER 90S TO NEAR 100 THIS AFTERNOON BUT NOT WIDESPREAD
ENOUGH FOR A HEAT ADVISORY.
630AM UPDATE...
UPDATE EARLY THIS MORNING TO LOWER THE CHANCES OF PRECIPITATION
OVER MUCH OF THE REGION THIS MORNING. THE EXCEPTION CONTINUES TO
BE THE NORTH AND MOUNTAINS WHERE OLD MCS CONTINUES TO DETERIORATE
AND MOVE EAST ACROSS MAINE. LATEST HRRR MODEL IS PICKING UP ON
THIS SYSTEM WELL THIS MORNING.
TIMING OF CONVECTIVE INITIATION TODAY APPEARS TO BE AROUND 16Z-
18Z OVER VERMONT. CELLS WILL ENTER NEW HAMPSHIRE BY AROUND 19Z OR 20Z
AND SPREAD QUICKLY TO THE EAST.
OTHERWISE...HAVE MADE SOME MINOR ADJUSTMENTS TO THE CLOUD...DEW
POINT AND MAX TEMPERATURE GRIDS BASED ON CURRENT TRENDS AND
OBSERVATIONS.
PREVIOUS DISCUSSION...
THE REMAINS OF AN MCS WILL CROSS NORTHERN SECTIONS EARLY THIS
MORNING...AS IT CONTINUES TO WEAKEN AS IT MOVES EAST. A DEVELOPING
WESTERLY FLOW ALOFT WILL ALLOW 850 MB TEMPERATURES TO CLIMB TO AT
OR ABOVE +16C DURING THE AFTERNOON HOURS. WITH AMPLE MIXING...WE
SHOULD EXPECT SOME LOWER 90S OVER SOUTHERN/CENTRAL NEW HAMPSHIRE
AND ADJACENT SECTIONS OF WESTERN MAINE. THERE WILL BE A SURFACE
TROUGH SITUATED NEAR AND ALONG THE COASTLINE...SO ONSHORE WINDS
WILL LIKELY KEEP THINGS COOLER OVER THE MIDCOAST REGION.
CAPES SOAR THIS AFTERNOON INTO THE 1500 J/KG RANGE OVER SOUTHERN
MAINE AND POSSIBLY SOUTHERN NEW HAMPSHIRE DURING THE AFTERNOON
HOURS TODAY AS A SHORT WAVE APPROACHES FROM THE WEST. LI VALUES
DROP SIGNIFICANTLY AS WELL. WE ARE NOT OUTLOOKED BY SPC
TODAY...HOWEVER FEEL COMPELLED TO AT LEAST MENTIONED GUSTY WINDS
AND SMALL HAIL IN THIS AREA.
PRECIPITABLE WATER VALUES WILL BE VERY HIGH TODAY...CLOSE TO 1.75
INCHES. WESTERLY FLOW SHOULD ALLOW FOR QUICK PROGRESSION OF
STORMS. NEVERTHELESS...ANY TRAINING ECHOES WILL NEED TO BE
MONITORED CLOSELY FOR THE THREAT OF HEAVY RAINFALL.
USED A BLEND OF MAV/MET MOS FOR DAYTIME MAX TEMPERATURES...WHICH
PLACES MANY AREAS IN THE LOWER 90S.
&&
.SHORT TERM /TONIGHT AND TUESDAY/...
PATCHY FOG WILL REDEVELOP TONIGHT...ESPECIALLY IN THE VALLEY
LOCATIONS. THEREAFTER...SHOWERS AND THUNDERSTORMS WILL DEVELOP
DURING THE EARLY AFTERNOON HOURS ON TUESDAY AS VORT MAX APPROACHES
FROM THE NORTH. EXPECT SEVERAL STORMS TO PRODUCE DAMAGING WIND
GUSTS AS THE PRIMARY THREAT FOR SEVERE WEATHER AS THE WIND MAX
CROSSES THE REGION...BUT WE CANNOT RULE OUT THE POSSIBILITY OF
LARGE HAIL AS WELL. WILL HIGHLIGHT THIS IN THE HWO.
EXPECT MANY COMMUNITIES TO TOP OUT AT OR ABOVE 90 DEGREES ONCE
AGAIN OVER SOUTHERN/CENTRAL NEW HAMPSHIRE AND WESTERN MAINE.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
THRU THE OUTLOOK PERIOD THE EVOLUTION OF A LONG WAVE TROUGH WILL
BECOME ESTABLISHED OVER THE EASTERN GREAT LAKES AND EXTEND SOUTH
INTO THE OHIO VALLEY. THIS LONG WAVE TROUGH WILL BECOME THE MAIN
WEATHER PRODUCER FOR THE FORECAST PERIOD OF WEDNESDAY THROUGH
SUNDAY. THE DEVELOPING EASTERN LONG WAVE TROUGH WILL MEAN A
CONTINUED MOIST AND UNSTABLE SSW FLOW AT THE SURFACE AND ALOFT
THRU THE WEEK. SHOWERS/THUNDERSTORMS ARE EXPECTED THROUGHOUT THE
WEEK AND INTO THE WEEKEND. TEMPERATURES WILL BE COOLER THROUGH THE
WEEK DUE TO PLENTY OF CLOUDS AND THE MOIST SOUTHERLY FLOW. HIGH
TEMPERATURES WILL BE MOSTLY IN THE 70S BUT DEW POINTS WILL REMAIN
HIGH SO IT WILL BE MUGGY AS WELL.
USED A BLEND OF THE MAV/MET GUIDANCE FOR 4TH/5TH PERIODS AND THEN
THE ADJUSTED MEX TEMPERATURES FOR DAYS 4-7.
&&
.AVIATION /13Z MONDAY THROUGH FRIDAY/...
SHORT TERM...WEST WINDS TODAY MAY GUST INTO THE LOWER 20S. WINDS
AND THE POTENTIAL FOR HAIL IS POSSIBLE OVER SOUTHERN AREAS OF
MAINE THIS AFTERNOON AND OVER ALL AREAS ON TUESDAY.
LONG TERM...
VARIABLE CONDITIONS EXPECTED THRU THE OUTLOOK PERIOD. VFR
CONDITIONS ARE EXPECTED AT TIMES BUT WILL LOWER TO MVFR TO IFR
IN SCATTERED SHOWERS/THUNDERSTORMS THROUGHOUT THE MIDDLE TO END OF
THE WEEK.
&&
.MARINE...
SHORT TERM...
WINDS MAY BECOME GUSTY OVER THE OUTER WATERS TODAY...BUT MOST
LIKELY REMAINING BELOW SCA CRITERIA. SIMILAR CONDITIONS WILL
FOLLOW ON TUESDAY.
LONG TERM...
WINDS/SEAS WILL REMAIN BELOW SCA CONDITIONS THRU THURSDAY BUT MAY
INCREASE TO SCA CRITERIA ON FRIDAY DUE TO AN INCREASING SOUTHERLY
PRESSURE GRADIENT ALLOWING WINDS AND SEAS TO INCREASE.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
NEAR TERM UPDATE...KIMBLE
SHORT TERM...CANNON
LONG TERM...MARINE
AREA FORECAST DISCUSSION
NWS GRAY ME
629 AM EDT MON JUN 24 2013
.SYNOPSIS...
WARM AND MOIST AIR CONTINUES TO POOL ALONG AND SOUTH OF A
STATIONARY FRONT SITUATED TO OUR NORTH. SCATTERED SHOWERS AND
THUNDERSTORMS ARE EXPECTED EACH DAY THROUGH THE WEEK AS SEVERAL
DISTURBANCES CROSS THE REGION. A LARGE UPPER LEVEL TROUGH WILL
APPROACH FROM THE WEST LATE IN THE WEEK. THIS WILL ALLOW FOR
COOLER TEMPERATURES...BUT INCREASE THE CHANCE FOR SHOWERS ACROSS
THE REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
UPDATE EARLY THIS MORNING TO LOWER THE CHANCES OF PRECIPTATION
OVER MUCH OF THE REGION THIS MORNING. THE EXCEPTION CONTINUES TO
BE THE NORTH AND MOUNTAINS WHERE OLD MCS CONTINUES TO DETEORATE
AND MOVE EAST ACROSS MAINE. LATEST HRRR MODEL IS PICKING UP ON
THIS SYSTEM WELL THIS MORNING.
TIMING OF CONVECTIVE INITIATION TODAY APPEARS TO BE AROUND 16Z-
18Z OVER VERMONT. CELLS WILL ENTER NEW HAMPSHIRE BY AROUND 19Z OR 20Z
AND SPREAD QUICKLY TO THE EAST.
OTHERWISE...HAVE MADE SOME MINOR ADJUSTMENTS TO THE CLOUD...DEW
POINT AND MAX TEMPERATURE GRIDS BASED ON CURRENT TRENDS AND
OBSERVATIONS.
PREV DISC...
THE REMAINS OF AN MCS WILL CROSS NORTHERN SECTIONS EARLY THIS
MORNING...AS IT CONTINUES TO WEAKEN AS IT MOVES EAST. A DEVELOPING
WESTERLY FLOW ALOFT WILL ALLOW 850 MB TEMPERATURES TO CLIMB TO AOA
+16C DURING THE AFTERNOON HOURS. WITH AMPLE MIXING...WE SHOULD
EXPECT SOME LOWER 90S OVER SOUTHERN/CENTRAL NH AND ADJACENT
SECTIONS OF WESTERN MAINE. THERE WILL BE A SURFACE TROUGH SITUATED
NEAR AND ALONG THE COASTLINE...SO ONSHORE WINDS WILL LIKELY KEEP
THINGS COOLER OVER THE MIDCOAST REGION.
CAPES SOAR THIS AFTERNOON INTO THE 1500 J/KG RANGE OVER SOUTHERN
MAINE AND POSSIBLY SOUTHERN NEW HAMPSHIRE DURING THE AFTERNOON
HOURS TODAY AS A SHORT WAVE APPROACHES FROM THE WEST. LIS DROP
SIGNIFICANTLY AS WELL. WE ARE NOT OUTLOOKED BY SPC TODAY...HOWEVER
FEEL COMPELLED TO AT LEAST MENTIONED GUSTY WINDS AND SMALL HAIL IN
THIS AREA.
PRECIPITABLE WATER VALUES WILL BE VERY HIGH TODAY...CLOSE TO 1.75
INCHES. WESTERLY FLOW SHOULD ALLOW FOR QUICK PROGRESSION OF
STORMS. NEVERTHELESS...ANY TRAINING ECHOES WILL NEED TO BE
MONITORED CLOSELY FOR THE THREAT OF HEAVY RAINFALL.
USED A BLEND OF MAV/MET MOS FOR DAYTIME MAX TEMPERATURES...WHICH
PLACES MANY AREAS IN THE LOWER 90S.
&&
.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
PATCHY FOG WILL REDEVELOP TONIGHT...ESPECIALLY IN THE VALLEY
LOCATIONS. THEREAFTER...SHOWERS AND THUNDERSTORMS WILL DEVELOP
DURING THE EARLY AFTERNOON HOURS ON TUESDAY AS VORT MAX APPROACHES
FROM THE NORTH. EXPECT SEVERAL STORMS TO PRODUCE DAMAGING WIND
GUSTS AS THE PRIMARY THREAT FOR SEVERE WEATHER AS THE WIND MAX
CROSSES THE REGION...BUT WE CAN`T RULE OUT THE POSSIBILITY OF LARGE
HAIL AS WELL. WILL HIGHLIGHT THIS IN THE HWO.
EXPECT MANY COMMUNITIES TO TOP OUT AT OR ABOVE 90 DEGREES ONCE
AGAIN OVER SOUTHER/CENTRAL NEW HAMPSHIRE AND WESTERN MAINE.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
THRU THE OUTLOOK PERIOD THE EVOLUTION OF A LONG WAVE TROF WILL
BECOME ESTABLISHED OVER THE ERN GT LAKES AND EXTEND S INTO THE
OHIO VALLEY. THIS L/WV TROF WILL BECOME THE MAIN WX PRODUCER FOR
THE FCST PERIOD OF WED-SUN. THE DEVELOPING EASTERN L/WV TROF WILL
MEAN A CONTINUED MOIST AND UNSTBL SSWLY FLOW AT THE SFC/ALOFT THRU
THE WEEK. SHWRS/TSTMS ARE EXPECTED THROUGHOUT THE WEEK AND INTO
THE WEEKEND. TEMPS WILL BE COOLER THROUGH THE WEEK DUE TO PLENTY
OF CLOUDS AND THE MOIST SLY FLOW. HIGH TEMPS WILL BE MOSTLY IN THE
70S BUT DEWPOINTS WILL REMAIN HIGH SO IT WILL BE MUGGY AS WELL.
USED A BLEND OF THE MAV/MET GUID FOR 4TH/5TH PERIODS AND THEN THE
ADJUSTED MEX TEMPS FOR DAYS 4-7.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
SHORT TERM...
MOISTURE TRAPPED UNDER AN INVERSION WILL KEEP PERIODS OF LIFR AND
VLIFR CEILINGS IN THE TERMINAL FORECASTS EARLY THIS MORNING. WEST
WINDS TODAY MAY GUST INTO THE LOWER 20S. WINDS AND THE POTENTIAL
FOR HAIL IS POSSIBLE OVER SOUTHERN AREAS OF MAINE THIS AFTERNOON
AND OVER ALL AREAS ON TUESDAY.
LONG TERM...
VARIABLE CONDS EXPECTED THRU THE OUTLOOK PERIOD. VFR CONDS ARE
EXPECTED AT TIMES BUT WILL LOWER TO MVFR TO IFR IN SCT SHWRS/TSTMS
THROUGHOUT THE MIDDLE TO END OF THE WEEK.
&&
.MARINE...
SHORT TERM...
WINDS MAY BECOME GUSTY OVER THE OUTER WATERS TODAY...BUT MOST
LIKELY REMAINING BELOW SCA CRITERIA. SIMILAR CONDITIONS WILL
FOLLOW ON TUESDAY.
LONG TERM...
WINDS/SEAS WILL REMAIN BLO SCA CONDS THRU THURSDAY BUT MAY
INCREASE TO SCA CRITERIA ON FRI DUE TO AN INCREASING SLY PRES
GRADIENT ALLOWING WINDS AND SEAS TO INCREASE.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HASTINGS NE
ISSUED BY NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
527 AM CDT MON JUN 24 2013
.DISCUSSION...
SCATTERED THUNDERSTORMS WILL MOVE THROUGH THE FORECAST AREA THIS
MORNING. A SEVERE WATCH CONTINUES FOR A FEW OF OUR NEBRASKA
COUNTIES UNTIL 6 AM...BUT OVERALL STORMS HAVE WEAKENED AND
EXISTING WATCH WILL PROBABLY BE ALLOWED TO EXPIRE ON SCHEDULE.
THUNDERSTORMS WILL PROBABLY HAVE ENDED ALTOGETHER BY 18Z AS THE
WEAK WAVE CONTINUES TO MOVE NORTHEAST OF THE AREA. ADDITIONAL
THUNDERSTORMS COULD DEVELOP IN OUR WESTERN FORECAST AREA LATE THIS
AFTERNOON AND COULD CONTINUE THROUGH THE EVENING HOURS WITH A
SLIGHT RISK FOR SEVERE STORMS DURING THIS TIME.
BEYOND TODAY AND TONIGHT...A PERIOD OF HOT WEATHER WILL CONTINUE
THROUGH MOST OF THE REMAINDER OF THE WEEK WITH AFTERNOON TEMPS IN
THE MID 90S TO LOWER 100S. THERE IS A WEAK FRONT THAT PUSHES
THROUGH THE AREA TUESDAY AFTERNOON...WHICH PROVIDES ONLY VERY
SLIGHT RELIEF PRIMARILY TO OUR NORTHERN FORECAST AREA. DID NOT
INCLUDE ANY PRECIP CHANCES WITH THE FRONT AS WE MAY BE TOO CAPPED
TO GET ANYTHING TO DEVELOP.
ALSO LEFT REMAINDER OF FORECAST DRY AS THE REGION REMAINS IN A
WEAK RIDGE PATTERN. CONFIDENCE LEVEL IS JUST TOO LOW TO
EFFECTIVELY TIME ANY SUBTLE WAVES THIS FAR OUT.
&&
.PREV DISCUSSION...
SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 317 PM CDT SUN JUN 23 2013
MORNING MAP ANALYSIS INDICATES QUASI ZONAL TO SOUTHWESTERLY MID TO
UPPER LEVEL FLOW OVER THE WESTERN HALF OF THE CONUS...WITH A
LONGWAVE RIDGE OVER THE EAST. A COUPLE OF MID LEVEL SHORT WAVES ARE
ALSO NOTED...WITH ONE EXTENDING FROM THE UPPER MISSISSIPPI VALLEY
INTO THE NORTHERN PLAINS...AND THE OTHER OVER THE SOUTHWESTERN
CONUS. MID TO UPPER LEVEL JET ENERGY EXTENDS FROM THE
WEST/SOUTHWESTERN CONUS...EAST/NORTHEAST INTO THE CENTRAL
PLAINS...AND THEN NORTH INTO SOUTH CENTRAL CANADA BEFORE FLOWING
EAST INTO SOUTHEASTERN CANADA AND PORTIONS OF THE NORTHEASTERN
CONUS. MID TO UPPER LEVEL FLOW OVER OUR AREA MAXES OUT AT AROUND
60KTS BETWEEN 300MB AND 200MB PER 12Z SOUNDING DATA FROM KLBF AND
KOAX. WATER VAPOR IMAGERY ALSO SHOWS THE AFOREMENTIONED MID LEVEL
SHORT WAVES...ALONG WITH A PAIR OF CLOSED MID LEVEL LOWS. ONE SUCH
LOW IS LOCATED OVER EASTERN ALBERTA AND WESTERN SASKATCHEWAN...AND
THE OTHER IS OVER THE PACIFIC JUST OFF THE COAST OF THE NORTHWESTERN
CONUS. AT THE SURFACE AN AREA OF LOW BAROMETRIC PRESSURE EXISTS OVER
SOUTHWESTERN KANSAS...WITH A FRONTAL BOUNDARY EXTENDING
NORTHEAST FROM THE LOW INTO NORTH CENTRAL KANSAS AND
SOUTHEASTERN NEBRASKA. THE LOW LEVEL WIND FIELD ACROSS MUCH OF OUR
CWA REMAINS FROM THE NORTHEAST FOR THE MOST PART...BUT LOCATIONS
ACROSS OUR SOUTHEAST SUCH AS KK82...KK61...AND KHJH ARE ALL
OBSERVING A SURFACE WIND FROM THE SOUTHEAST.
GUIDANCE FROM THE NAM...OPERATIONAL GFS...EC...AND SREF-MEAN
SUGGESTS THE LOW LEVEL BAROCLINIC ZONE WILL PERSIST OVER
SOUTHEASTERN PORTIONS OF OUR CWA THIS EVENING INTO TONIGHT BEFORE
SURGING NORTH DURING THE DAY MONDAY. THERE ARE
INDICATIONS...ESPECIALLY FROM HIGHER RESOLUTION MODELS SUCH AS THE
NAM12...OF VERY SUBTLE MID LEVEL PERTURBATIONS MOVING OVERHEAD
WITHIN THE MEAN FLOW THIS AFTERNOON AND THIS EVENING. CONFIDENCE ON
SUCH A FEATURE PROMOTING PRECIPITATION PRODUCTION ACROSS OUR AREA
THIS AFTERNOON AND EVENING REMAINS VERY LOW HOWEVER AND AS A
RESULT...WILL CONTINUE RELEGATING ANY AFTERNOON AND EVENING POPS TO
OUR SOUTH/SOUTHEASTERN CWA...IN CLOSEST PROXIMITY TO THE
AFOREMENTIONED LOW LEVEL BAROCLINIC ZONE AND RESULTANT AXIS OF
ENHANCED LOW LEVEL CONVERGENCE AND LIFT. AS FOR THE TIMING OF
CONVECTIVE INITIATION THIS AFTERNOON AND EVENING...FORECAST PROXIMITY
SOUNDINGS FROM THE NAM...OPERATIONAL GFS...AND RAP ALL SUGGEST A
HEALTHY CAP PERSISTING THROUGH AT LEAST 00Z. GIVEN THIS...ITS HARD
TO BUY INTO QPF FIELDS FROM THE NAM...OPERATIONAL GFS...EC...AND
SREF-MEAN...WHICH ALL SUGGEST WIDESPREAD PRECIPITATION WILL BE REALIZED ACROSS
PORTIONS OF OUR SOUTHEAST BEFORE 00Z THIS EVENING. HRRR SIMULATED
REFLECTIVITY LOOKS MUCH MORE REASONABLE...SUGGESTING VERY ISOLATED
CONVECTION OCCURRING ACROSS OUR SOUTHEAST TOWARDS 00Z. GIVEN ALL
THIS...CONFIDENCE IS VERY LOW THAT MUCH PRECIPITATION WILL BE
REALIZED ACROSS OUR AREA PRIOR TO 00Z...BUT CANNOT COMPLETELY RULE
OUT SUCH A SOLUTION AND WILL MAINTAIN ~20% POPS ACROSS OUR SOUTHEAST
23-00Z. 00Z AND BEYOND...FORECAST PROXIMITY SOUNDINGS SUGGEST THE CAPPING
INVERSION WILL WEAKEN SOMEWHAT THUS MAKING CONVECTION SOMEWHAT MORE
LIKELY...A SOLUTION SUPPORTED BY QPF FIELDS FROM THE
NAM...OPERATIONAL GFS...EC...AND SREF-MEAN...AS WELL AS SIMULATED
REFLECTIVITY FROM THE HRRR. GIVEN THIS...WILL GO AHEAD WITH SLIGHTLY
HIGHER POPS...~%30...00-06Z ACROSS OUR SOUTHEAST. SHOULD
SURFACE-BASED CONVECTION BE REALIZED THIS AFTERNOON AND/OR
EVENING...THEN SEVERE WEATHER WILL LIKELY RESULT WITH DEEP LAYER
MUCAPE VALUES IN THE 2000-4000J/KG WAITING FOR UPDRAFT PRODUCTION
AND 30-35KTS OF DEEP LAYER BULK SHEAR FOR UPDRAFT ENHANCEMENT.
CERTAINLY LARGE HAIL AND MICROBURST-RELATED WIND GUSTS WILL BE A
THREAT...BUT ENHANCED HORIZONTAL VORTICITY IN THE VICINITY OF THE
LOW LEVEL BAROCLINIC ZONE COULD ALSO PROMOTE ISOLATED TORNADIC
ACTIVITY. WILL CONTINUE SUCH WORDING IN THE HWO AS A RESULT.
HEADING INTO THE OVERNIGHT HOURS TONIGHT...THE AXIS OF A ~45KT 850MB
JET STREAK IS EXPECTED TO DEVELOP ACROSS PORTIONS OF WESTERN AND
CENTRAL KANSAS...WITH THE NOSE OF THIS LOW LEVEL JET MOVING INTO
SOUTHERN PORTIONS OF OUR CWA BETWEEN 06Z AND 12Z. SHOULD DEEP
CONVECTION BE ONGOING ALONG THE LOW LEVEL BAROCLINIC ZONE...THEN
INCREASING LOW LEVEL THERMAL ADVECTION ALONG THE AXIS OF THE LOW
LEVEL JET COULD CERTAINLY HELP INCREASE SPATIAL COVERAGE OF SAID
CONVECTIVE ACTIVITY. ALSO...IN ADDITION TO POSSIBLE THUNDERSTORM
ACTIVITY OVER PORTIONS OF OUR CWA THIS AFTERNOON AND
EVENING...THUNDERSTORMS ALSO REMAIN POSSIBLE OVER THE CENTRAL HIGH
PLAINS. SHOULD HIGH PLAINS CONVECTION DEVELOP THIS AFTERNOON/EVENING
AND MOVE EAST TOWARDS OUR AREA TONIGHT...ADDITIONAL SHOWER AND
THUNDERSTORM ACTIVITY COULD BE REALIZED OVER OUR AREA
TONIGHT...ESPECIALLY OUR WEST. THIS IS A SOLUTION SUPPORTED BY THE
NAM...OPERATIONAL GFS...SREF-MEAN...AND HRRR. GIVEN ALL THIS...WENT
AHEAD WITH RELATIVELY HIGHER POPS ACROSS MUCH OF THE CWA STARTING
AROUND 06Z. SEVERE WEATHER COULD CERTAINLY BE POSSIBLE DURING THE
EARLY PART OF THE OVERNIGHT HOURS AS THE MORE ROBUST CONVECTION FROM
EARLIER IN THE EVENING...SHOULD IT DEVELOP...MAINTAINS ITSELF. THAT
BEING SAID...BARRING THE DEVELOPMENT OF AN MCS ACROSS THE
REGION...CONVECTIVE ACTIVITY SHOULD WANE IN INTENSITY AS POTENTIAL
INSTABILITY DECREASES 06Z ONWARD.
THERE COULD SOME LINGERING SHOWER AND THUNDERSTORM ACTIVITY ACROSS
OUR AREA AROUND SUNRISE MONDAY...BUT OTHERWISE MONDAY DURING THE DAY
IS EXPECTED TO REMAIN DRY FOR THE MOST PART AS THE WARM FRONT SURGES
NORTH AND AN OVERALL LACK IN KINEMATIC FORCING OVERTAKES THE AREA.
AT THIS TIME THE ONLY REAL THREAT FOR PRECIPITATION DURING THE DAY
MONDAY APPEARS AS THOUGH IT WILL RESIDE OVER OUR SOUTHWESTERN CWA
DURING THE LATE AFTERNOON AND EVENING HOURS...WHICH IS WHERE AND
WHEN GUIDANCE SUGGESTS AN ADVANCING LOW LEVEL DRY LINE WILL BULGE EAST.
AN AREA OF LOCALLY ENHANCED CONVERGENCE AND LIFT IN THE VICINITY OF
THIS DRY LINE BULGE...WORKING IN CONCERT WITH DIABATIC HEATING...MAY
BE ENOUGH TO INITIALIZE ISOLATED SHOWER AND THUNDERSTORM DEVELOPMENT
AND AS A RESULT...~20% POPS ARE FORECAST 21Z MONDAY THROUGH 00Z
TUESDAY ACROSS OUR SOUTHWEST. SHOULD THUNDERSTORM ACTIVITY BE REALIZED LATE
MONDAY AFTERNOON AND/OR EVENING...THEN DEEP LAYER MUCAPE VALUES OF
2000-3000J/KG...ALONG WITH DEEP LAYER BULK SHEAR VALUES OF
~30KTS...WILL BE AVAILABLE FOR UPDRAFT PRODUCTION AND ENHANCEMENT.
GIVEN THIS...WILL GO AHEAD AND HIGHLIGHT THE THREAT FOR ISOLATED
SEVERE WEATHER ACROSS OUR SOUTHWEST MONDAY AFTERNOON AND EVENING.
FINALLY...INCREASING SOUTHERLY FLOW WILL LIKELY BE OBSERVED MONDAY
AFTERNOON ONCE THE SURFACE WARM FRONT SURGES NORTH. GUIDANCE
SUGGESTS A SUSTAINED WIND OF ~24KTS...WITH HIGHER GUSTS APPROACHING
35KTS...WILL BE REALIZED PRIMARILY ACROSS NORTH CENTRAL KANSAS. AS A
RESULT...WILL CONTINUE MENTIONING SUCH CONDITIONS IN THE HWO.
LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 317 PM CDT SUN JUN 23 2013
MONDAY NIGHT...A VORT MAX LOCATED OVER THE HIGH PLAINS WILL TRACK
EAST ACROSS THE FORECAST AREA. THUNDERSTORMS THAT INITIALLY FORM
ACROSS THE HIGH PLAINS DURING THE MONDAY AFTERNOON HOURS WILL SLIDE
EAST DURING THE EVENING AND OVERNIGHT HOURS...AND IF THEY HOLD
TOGETHER MAY BRING RAIN TO PORTIONS OF THE FORECAST AREA. IN
ADDITION TO RAIN...SOME OF THESE THUNDERSTORMS MAY BE SEVERE WITH
LARGE HAIL AND DAMAGING WINDS POSSIBLE DURING THE EVENING HOURS.
INSTABILITY IS HIGH AND DEEP LAYER SHEAR IS MORE MODEST BUT
SUFFICIENT FOR SEVERE STORMS. THE LIMITING FACTOR WILL BE THE WARM
MID LEVEL CAP AND THUS CONFIDENCE IN THUNDERSTORM DEVELOPMENT AND
COVERAGE IS STILL FAIRLY LOW WITH SLIGHT POPS. THE 12Z ECMWF AND 12Z
NAM FAVOR OUR WEST AND NORTH FOR STORMS...WHILE THE 12Z GFS
HIGHLIGHTS OUR SOUTHEASTERN ZONES. THE ECMWF AND NAM MAKE MORE SENSE
WITH FAVORING NORTH AND WEST ZONES BASED ON THE EXPECTED UPPER WAVE
LOCATION AND THE INCREASING STRENGTH OF THE CAP AS YOU HEAD SOUTH.
TUESDAY AND WEDNESDAY...THE PATTERN WILL BE FAIRLY ZONAL WITH ALL
OF THE BETTER UPPER FLOW AND SHORT WAVES TRACKING ACROSS THE
NORTHERN TIER STATES. AN UPPER RIDGE WILL SLOWLY BEGIN TO BUILD
ACROSS THE SOUTHWEST CONUS STARTING ON WEDNESDAY. A SFC TROUGH AXIS
WILL TRACK EAST THROUGH OUR FORECAST AREA LATE ON TUESDAY AND TURN
THE WINDS TO NORTHERLY BY WEDNESDAY. HOWEVER...A STRONG CAP SHOULD
RESULT IN DRY CONDITIONS FOR MOST AREAS AND WILL CONTINUE TO CALL
FOR A DRY FORECAST...BUT CAN NOT COMPLETELY RULE OUT AN ISOLATED
THUNDERSTORM...HENCE THE 10 PERCENT POPS. TUESDAY WILL BE SCORCHER
WITH HIGHS WELL INTO THE 90S ACROSS NEBRASKA TO OVER 100 ACROSS MUCH
OF NORTHERN KANSAS. TEMPERATURES WILL FALL A FEW DEGREES WITH THE
NORTH WINDS ON WEDNESDAY...BUT CONTINUE TO EXPECT 90S FOR HIGHS.
THURSDAY THROUGH SUNDAY...THERE IS A SHIFT IN THE UPPER PATTERN AS
AN UPPER RIDGE STRENGTHENS ACROSS THE ROCKIES AND AN UPPER TROUGH
PERSISTS ACROSS THE EASTERN CONUS. THIS WILL RESULT IN NORTHWESTERLY
FLOW ALOFT FOR OUR FORECAST AREA. MOST AREAS WILL BE DRY THROUGHOUT
THIS PERIOD GIVEN A LACK OF FORCING. THERE IS A SLIGHT CHANCE OF
THUNDERSTORMS ON THURSDAY INTO THURSDAY NIGHT...BUT MOST RESENT
MODEL RUNS ARE STARTING TO BACK OFF OF THIS ALREADY RATHER SLIGHT
CHANCE OF PRECIPITATION. ANOTHER WEAK COOL FRONT WILL TRY TO WORK
ITS WAY THROUGH AT SOME POINT THURSDAY NIGHT OR FRIDAY...BUT THURSDAY
SHOULD STILL BE A HOT DAY WITH 90S ACROSS NEBRASKA TO NEAR 100 IN
KANSAS. THE COOLER WEATHER WILL SETTLE IN ON FRIDAY AND SATURDAY
WITH EASTERLY TO NORTHEASTERLY SFC WINDS. THIS COOLER FETCH SHOULD
DROP HIGHS BACK INTO THE LOWER AND MID 90S ON FRIDAY...AND THEN 80S
ACROSS NEBRASKA TO LOWER 90S OVER KANSAS ON SATURDAY. TEMPERATURES
BEGIN TO WARM BACK UP ON SUNDAY WITH EVERYONE BACK IN THE 90S.
OVERALL...TEMPERATURES WILL NOT VARY THAT MUCH AND REMAIN RATHER
TOASTY.
AVIATION...(FOR THE 06Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 115 AM CDT MON JUN 24 2013
GENERALLY VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. CONVECTION
DEVELOPING OFF THE HIGHS PLAINS EARLY TONIGHT WILL SHIFT NEWD AND MAY
IMPACT THE GRI TERMINAL AROUND 9-11Z AND WILL INCLUDE A TEMPO GROUP
FOR THIS. OTHERWISE SOME MVFR CIGS ARE AROUND THE REGION...BUT WE
EXPECT MUCH OF THIS TO LIFT NWD OVERNIGHT BUT SOME MVFR CIGS/VISBY
ARE POSSIBLE IN THE TSRA. OTHERWISE SOUTHERLY WINDS WILL INCREASE
THROUGH THE DAY ON MON.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1016 AM EDT MON JUN 24 2013
.SYNOPSIS...
VERY WARM AND HUMID CONDITIONS WILL REMAIN IN PLACE ACROSS THE
REGION FOR THE BULK OF THIS WEEK...BUT UNLIKE THE PAST FEW DAYS WHEN
THUNDERSTORMS WERE FEW AND FAR BETWEEN...CONVECTION WILL GRADUALLY
BECOME MORE WIDESPREAD.
&&
.NEAR TERM /THROUGH TONIGHT/...
12Z BUF SOUNDING SHOWS MORE INSTABILITY AND PRECIPITABLE WATER
COMPARED TO YESTERDAY. IN ADDITION...WILL HAVE TO DEAL WITH UPPER
LEVEL TROUGH CLEARLY SEEN IN WATER VAPOR IMAGERY OVER PA MOVING NE.
EXPECT CONVECTION TO FIRE ONCE WE CAN GET SOME SURFACE BASED LIFT
EARLY THIS AFTERNOON...PROBABLY ALONG A LAKE ERIE BREEZE SIMILAR TO
SUNDAY. THIS SHOULD BE ON THE NW OR W SIDE OF THE ABOVE MENTIONED
UPPER LEVEL DISTURBANCE. WINDS ALOFT ARE FORECAST TO BE ABOUT 15-20
KTS...ALTHOUGH PRECIPITABLE WATER IS EXPECTED TO BE ON THE
DECREASE. THERE WILL BE A THREAT FOR SLOW MOVING STORMS AGAIN
TODAY...BUT CONFIDENCE IS NOT HIGH ENOUGH FOR A FLASH FLOOD WATCH.
BASED ON MESOSCALE MODEL GUIDANCE /SSEO AND HRRR AND LOCAL MODELS/
THE BIGGEST THREAT APPEARS TO BE WELL INLAND...FINGER LAKES AND/OR
CENTRAL NY. WILL KEEP THE WELL THOUGHT OUT LIKELY POPS FROM
CONTINUITY FOR THAT REGION. OTHERWISE...EXPECT ANOTHER WARM/HUMID
DAY WITH PARTIAL SUNSHINE.
WARMING MID LEVELS AND GENERAL SUBSIDENCE WILL BE FOUND IN THE WAKE
OF THE EXITING CIRCULATION MONDAY NIGHT. THIS IN COMBINATION WITH
THE WEAKENING OF THE DIURNAL INSTABILITY SHOULD LEAD TO ANOTHER FAIR
WARM AND HUMID NIGHT...ALTHOUGH CONVECTION IN THE AFOREMENTIONED
AREAS WILL STILL BE WANING DURING THE EVENING HOURS.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
ON TUESDAY...YET ANOTHER IN A SERIES OF MID LEVEL SHORTWAVES WILL
WORK FROM THE CENTRAL TO LOWER GREAT LAKES IN THE NEARLY ZONAL FLOW
ALOFT. WHILE THE 00Z GUIDANCE SUITE CONTINUES TO SHOW SOME
DISAGREEMENT IN THE TIMING OF THIS WAVE...A ROUGH MODEL CONSENSUS
SUGGESTS THAT THIS FEATURE WILL AT LEAST GET CLOSE ENOUGH TO ACT AS
A TRIGGER FOR CONVECTION AT SOME POINT...POTENTIALLY AS EARLY AS
TUESDAY MORNING ACROSS FAR WESTERN NEW YORK PER THE MORE CONSISTENT
GFS/ECMWF SOLUTIONS. COUPLED WITH DIURNAL HEATING OF OUR VERY WARM
AND HUMID AIRMASS AND RESULTANT SBCAPES OF 1000-2000 J/KG...THIS
SHOULD RESULT IN ANOTHER ROUND OF AT LEAST SCATTERED CONVECTION
AREAWIDE. THE GREATEST AREAL COVERAGE WILL ONCE AGAIN BE MOST LIKELY
FROM THE SOUTHERN TIER NORTHEASTWARD ACROSS THE GENESEE VALLEY/
FINGER LAKES TO INTERIOR PORTIONS OF THE NORTH COUNTRY...WHERE LOW
LEVEL INSTABILITY WILL BE MAXIMIZED AND LAKE BREEZE BOUNDARIES
SHOULD PROVIDE ADDED LOCALIZED LIFT OF THE UNSTABLE AIRMASS. A
SLIGHTLY STRONGER MID LEVEL TROPOSPHERIC FLOW COMPARED TO THE
PREVIOUS FEW DAYS SHOULD MEAN THAT THERE WILL AT LEAST BE A SOMEWHAT
LOWER RISK FOR LOCALIZED HEAVY RAINFALL/FLOODING...HOWEVER THIS
MAY ALSO LEAD TO A SOMEWHAT GREATER POTENTIAL FOR A FEW STRONGER
STORMS...PARTICULARLY ACROSS THE NORTH COUNTRY AND SAINT LAWRENCE
VALLEY WHERE THE OVERALL MID LEVEL FLOW SHOULD BE STRONGEST.
DURING THE COURSE OF TUESDAY NIGHT...CONVECTION SHOULD GENERALLY BE
ON A DOWNWARD TREND THROUGH MUCH OF THE THE NIGHT...THOUGH THE EXACT
SPEED OF THIS DIMINISHING TREND NOW APPEARS TO BE MUCH MORE IN
QUESTION COMPARED TO 24 HOURS AGO. OF THE AVAILABLE GUIDANCE...THE
ECMWF REMAINS VERY CONSISTENT WITH ITS PREVIOUS RUNS IN ADVECTING A
SUBSTANTIAL SURGE OF DRIER AIR ALOFT INTO THE AREA IN THE WAKE OF
TUESDAY`S SHORTWAVE AND ITS ATTENDANT WEAK FRONTAL BOUNDARY ...WHICH
RESULTS IN CONVECTION QUICKLY DIMINISHING ACROSS THE AREA DURING THE
EVENING...FOLLOWED BY MAINLY DRY WEATHER FOR A TIME BEFORE SOME
ADDITIONAL UPSTREAM CONVECTION ARRIVES LATER ON IN THE NIGHT. IN
CONTRAST...THE GFS/GEM ARE A BIT SLOWER WITH THE DEPARTURE OF
SHORTWAVE ENERGY ALOFT...AND CONSEQUENTLY ADVECT ANOTHER ROUND OF
UPSTREAM CONVECTION /AND POTENTIALLY AN MCS/ ACROSS THE AREA DURING
THE EVENING...FOLLOWED BY DECENT DRYING FROM WEST TO EAST OVERNIGHT.
MEANWHILE...THE NAM IS A SUBSTANTIAL OUTLIER IN LINGERING THE
AFOREMENTIONED SURFACE FRONT ACROSS THE AREA THROUGH THE NIGHT...
WITH ADDITIONAL CONVECTION RIPPLING EAST ALONG AND NORTH OF THIS
BOUNDARY RIGHT THROUGH THE NIGHT.
THROWING OUT THE 00Z NAM...WHICH IS OUT OF SYNC WITH ALL OF THE
OTHER GUIDANCE AND PER EXPERIENCE IS USUALLY NOT AS RELIABLE THIS
FAR OUT...WILL AIM MORE CONSERVATIVE AND KEEP AT LEAST A LOW CHANCE
OF CONVECTION IN AREAWIDE FOR THE FIRST HALF OF THE NIGHT GIVEN THE
AFOREMENTIONED UNCERTAINTIES IN TIMING...FOLLOWED BY A RETURN TO
MAINLY DRY CONDITIONS OVERNIGHT FOLLOWING A ECMWF/GFS/GEM CONSENSUS
AND OUR PREVIOUS CONTINUITY.
ON WEDNESDAY...IT APPEARS TO BE A CASE OF DEJA VU AS THE NEXT AND
POTENTIALLY STRONGER SHORTWAVE TROUGH AND ASSOCIATED SURFACE
REFLECTION SETTLES ACROSS THE GREAT LAKES...WITH AN ASSOCIATED WARM
FRONTAL BOUNDARY DEVELOPING EASTWARD ACROSS THE LOWER GREAT LAKES
AND NEW YORK STATE. COUPLED WITH INCREASING DAYTIME INSTABILITY...
THIS WILL ONCE AGAIN LEAD TO INCREASING CHANCES OF CONVECTION FROM
WEST TO EAST...AGAIN POTENTIALLY BEGINNING EARLY IN THE DAY ACROSS
EXTREME FAR WESTERN NEW YORK AS THE LEAD EDGE OF THIS NEXT SYSTEM
INTERACTS WITH SOME ELEVATED INSTABILITY. AS SUCH...WILL HAVE
BROADBRUSH CHANCE POPS IN PLAY...AND GENERALLY INCREASING FROM WEST
TO EAST THROUGH THE COURSE OF THE DAY.
WEDNESDAY NIGHT AND THURSDAY...THE AXIS OF THE AFOREMENTIONED
SHORTWAVE TROUGH AND MODEST SURFACE WAVE WILL TRANSLATE FURTHER
EAST INTO THE LOWER GREAT LAKES AND NEW YORK STATE. THIS WILL LEAD
TO A FURTHER UPTICK IN CONVECTIVE CHANCES...PARTICULARLY DURING THE
DAY ON THURSDAY WHEN THESE FEATURES WILL MOVE OVERHEAD...AND WILL
ONCE AGAIN BE ABLE TO TAKE ADVANTAGE OF INCREASING DIURNAL
INSTABILITY. WILL THUS CONTINUE TO INDICATE AN INCREASING TREND IN
POPS THROUGH THESE TWO PERIODS...CULMINATING IN A MIX OF HIGH CHANCE
TO LOW LIKELY VALUES ON THURSDAY...WITH THE HIGHEST VALUES ACROSS
THE NORTH COUNTRY/SAINT LAWRENCE VALLEY...WHICH WILL BE ALONG AND
NORTH OF THE TRACK OF THE SURFACE LOW/ATTENDANT WARM FRONT. THURSDAY
NIGHT...WILL KEEP BROADBRUSH HIGH CHANCE POPS ACROSS THE REGION AS
THE BROAD SURFACE WAVE LINGERS IN PLACE OVERHEAD...AND THE MID LEVEL
SHORTWAVE TROUGH BEGINS TO DEEPEN AS IT STARTS TO GET REINFORCED BY
ADDITIONAL SHORTWAVE ENERGY DROPPING SOUTHEAST FROM CENTRAL CANADA.
AS FOR TEMPERATURES...WARM AND HUMID WEATHER WILL CONTINUE TO BE THE
RULE THROUGH THIS PERIOD AS 850 MB TEMPS REMAIN LOCKED IN THE +16C
TO +18C RANGE...AND SURFACE DEWPOINTS LINGER IN THE MID TO UPPER
60S. THE WARMEST TEMPS WILL LIKELY OCCUR TUESDAY AND WEDNESDAY WHEN
PRECIPITATION/CLOUD COVERAGE WILL BE SOMEWHAT LESS...ALLOWING HIGH
TEMPS TO REACH INTO THE MID-UPPER 80S IN MOST PLACES...THOUGH AREAS
IMMEDIATELY NORTHEAST OF THE LAKES WILL LIKELY BE SOMEWHAT COOLER
DUE TO THE PREVAILING SOUTHWESTERLY LOW LEVEL FLOW. THURSDAY WILL
THEN LIKELY BE A LITTLE COOLER AS CONVECTIVE COVERAGE INCREASES...
WITH READINGS GENERALLY PEAKING IN THE LOWER TO MID 80S.
MEANWHILE...NIGHTTIME PERIODS WILL REMAIN RATHER SULTRY...WITH TEMPS
ONLY SETTLING INTO THE 65-70 DEGREE RANGE EACH NIGHT.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
DURING THE LONG TERM PERIOD...ROBUST LARGE-SCALE TROUGHING WILL
DEVELOP ACROSS OUR REGION AS PLENTIFUL SHORTWAVE ENERGY OVER
CENTRAL CANADA DROPS SOUTHEASTWARD INTO THE EXISTING MODEST MID
LEVEL TROUGH OVER THE GREAT LAKES...EVENTUALLY CARVING OUT A
SUBSTANTIAL UPPER LEVEL TROUGH IN THE PROCESS. THIS WILL RESULT IN
CONTINUED UNSETTLED WEATHER RIGHT THROUGH NEXT WEEKEND AS HEIGHT
FALLS/COOLING TEMPS ALOFT OVERSPREAD LINGERING WARM AND HUMID AIR
IN THE BOUNDARY LAYER. THIS WILL ESPECIALLY BE THE CASE DURING THE
DAYLIGHT HOURS OF FRIDAY AND SATURDAY WHEN THE BEST COMBINATIONS
OF INSTABILITY... AVAILABLE MOISTURE...AND LARGE-SCALE FORCING
WILL BE REALIZED... FOR WHICH HIGH CHANCE TO LOW LIKELY POPS WILL
BE IN PLAY. BY SUNDAY...CONVECTIVE POTENTIAL AND COVERAGE SHOULD
BEGIN TO LOWER SOMEWHAT AS THE AXIS OF DEEPEST MOISTURE ASSOCIATED
WITH THE TROUGH SHIFTS A LITTLE TO OUR EAST...THOUGH SCATTERED
SHOWERS AND STORMS WILL REMAIN A DISTINCT POSSIBILITY.
OVER TIME...THIS EVOLUTION IN THE PATTERN WILL ALSO LEAD TO A
GRADUAL AND MODEST REDUCTION IN TEMPERATURE AND HUMIDITY LEVELS AS
SOMEWHAT COOLER/DRIER AIR WORKS INTO OUR REGION...WITH READINGS
FALLING BACK TO NORMAL EARLY SUMMER LEVELS BY NEXT WEEKEND. MORE
SPECIFICALLY...850 MB TEMPS WILL GRADUALLY SETTLE FROM THE MID TEENS
BACK TO THE +12C TO +14C RANGE...AND THIS COUPLED WITH INCREASED
CLOUD COVER AND PRECIPITATION WILL RESULT IN DAYTIME HIGHS SLIPPING
BACK TO THE UPPER 70S/LOWER 80S FOR FRIDAY AND SATURDAY...AND THE
MID AND UPPER 70S BY SUNDAY. MEANWHILE...SURFACE DEWPOINTS WILL DROP
BACK TO SOMEWHAT MORE COMFORTABLE LEVELS IN THE UPPER 50S/LOWER 60S.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
WHILE VFR CONDITIONS WILL BE FOUND AT ALL OF THE COMMERCIAL AVIATION
SITES THIS AFTERNOON...THERE WILL BE AN INCREASED THREAT FOR
CONVECTION. THIS WILL MAINLY BE THE CASE OVER THE SRN TIER AND
FINGER LAKES REGION... WHERE SLOW MOVING THUNDERSTORMS THIS
AFTERNOON AND EVENING COULD PRODUCE HEAVY RAINS AND POSSIBLY SOME
SMALL HAIL. ANY SUCH CONVECTION WILL THEN WEAKEN AND DISSIPATE
WITHIN A COUPLE HOURS AFTER SUNSET...LEAVING MAINLY VFR CONDITIONS
IN PLACE FOR TONIGHT.
OUTLOOK...
TUESDAY THROUGH THURSDAY...MAINLY VFR WITH A CHANCE OF SHOWERS AND
THUNDERSTORMS.
&&
.MARINE...
HIGH PRESSURE WELL OFF THE SOUTHEAST COAST WILL KEEP A RELATIVELY
WEAK SFC PRESSURE GRADIENT OVER THE LOWER GREAT LAKES INTO THE
MIDDLE OF THE COMING WEEK. THIS WILL RESULT IN LIGHT SOUTH TO
SOUTHWEST WINDS ON BOTH LAKES ERIE AND ONTARIO...WITH NEGLIGIBLE
WAVES.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...RSH
NEAR TERM...RSH/ZAFF
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...RSH/ZAFF
MARINE...RSH
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
1006 AM EDT MON JUN 24 2013
.DISCUSSION...
VORT MAX ASSOCIATED WITH CONVECTION OVER W KY STILL LOOKS TO BE
SLOWLY DRIFTING TOWARD OUR AREA. THE APPROACH OF THIS FEATURE WILL
BRING AN INCREASE IN MOISTURE AND HELP TO TRIGGER CONVECTION THIS
AFTERNOON. LATEST RUC SOUNDINGS SHOW CAPES GENERALLY RANGING FROM
2000 TO 2500 J/KG BY 18Z. SOME AREAS MAY BECOME SLIGHTLY MORE OR
LESS UNSTABLE DEPENDING ON CLOUD COVER. IT STILL LOOKS LIKE AREAS TO
THE WEST HAVE GREATER CHANCES OF SEEING CONVECTION...AS LATEST NAM
AND RUC MODELS DEVELOP CONVECTION OVER MIDDLE TN AND ADVANCE IT
TOWARDS THE PLATEAU. CONVECTIVE COVERAGE SHOULD BE A LITTLE MORE
WIDESPREAD THAN THE PAST FEW DAYS AND NOT LIMITED TO ONLY THE HIGHER
ELEVATIONS. ALSO...CAN`T RULE OUT AN ISOLATED SEVERE STORM TODAY DUE
TO INCREASED INSTABILITY AND MOISTURE...WITH THE MAIN THREAT BEING
DAMAGING WINDS. LOCALLY HEAVY RAINFALL IS ALSO POSSIBLE DUE TO SLOW
STORM MOTIONS OF AROUND 9 KTS.
OVERALL...CURRENT FORECAST APPEARS TO BE ON TRACK. NO UPDATES
PLANNED AT THIS TIME.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 88 68 90 70 90 / 40 30 30 10 30
KNOXVILLE MCGHEE TYSON AIRPORT, TN 87 67 89 69 90 / 40 30 20 10 30
OAK RIDGE, TN 86 67 89 69 90 / 40 20 20 10 30
TRI CITIES AIRPORT, TN 87 64 88 63 89 / 30 20 30 10 30
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
SR
AREA FORECAST DISCUSSION
NWS SPOKANE WA
444 AM PDT Mon Jun 24 2013
.SYNOPSIS...
A wet pattern will continue across the Inland Northwest through
mid week...with frequent showers and scattered thunderstorms
common. The weather the second half of the week will be
dramatically different as a warming and drying trend quickly
develops by late week. Summer-like temperatures will be possible
by the weekend.
&&
.DISCUSSION...
Today and tonight...Offshore low pressure buttressed against
interior ridging with an axis positioned over Eastern Montana
is allowing a moist and very dynamic southwest flow of moisture
and energy to continue to pass through Eastern Washington and
Northern Idaho. Negatively tilted shortwaves ejecting up through
this flow have enough energy to merit not only high pops and
moderate QPF for rain but also the mention of thunderstorms.
Recent HRRR model runs hint at once the elevated forced convective
showers and thunderstorms pass associated with the largest
baroclinic negatively tilted frontal zone passing through right
now there will be not so much a break in the activity but a
decreasing trend between the time when the elevated convection
either exits into Canada or erodes/weakens some along its back
trailing edges and the time near 18Z and beyond where surface
based convection is expected to start filling in the breaks.
Therefore the forecast will remain cluttered with moderate to high
pops, QPF, along with some mention of thunderstorms that decreases
substantially with loss of daytime heating allowing the surface
based convection to subside...especially noted after 6Z tonight.
/Pelatti
Tues through Fri Nt: This four-day period will be the transition
period characterized by wet weather Tue and Wed, then by a rapid
warming and drying trend Thurs and Fri. The primary concern will
be how much pcpn will fall in the mtn zones of Nrn Wa, the Id
Panhandle and the East Slopes of the Cascades. Three-day model
guidance QPF is depositing (through about Wed) big ranges anywhere
from 0.60-1.50 inches for these zones... with the SREF the least
and the GFS the highest amnts. A complicating factor in our pcpn
amnt fcst is the number of quick-moving waves that track across
the Pac Nw through mid-week. There are at least four subtle
features (depending on the model), all of which contain a decent
SW moisture tap, with pwat values averaging around one inch. The
latest TPW loop shows a nearly SW-to-NE plume of 200% of normal
values aimed at Nrn Calif. Our waves should be able to tap into at
least 100-150% values. Adding to the complexity of the wide-
ranging rainfall amnts is the element of instability, especially
late afternoon. This will be the dominating factor that will
produce wide-ranging rainfall amnts over very short distances.
Streams that will be affected most will be those across NE WA and
the N Id Panhandle...especially where the recent heavy pcpn fell the
last couple weeks...as well as the Stehekin River near the Cascade
crest.bz
Saturday through Monday...A ridge of high pressure will build north
near the Inland Northwest, bringing with it drying conditions and
above normal temperatures. The extended models are consistent in
building a ridge into the region, but how amplified the ridge is
and its placement are still in question. The difference is
forecasting temperatures in the 90s to temperatures a little
"cooler" in the 80s. Previous forecasts had lowered temperatures
a tad on Saturday and did not see any reason to deviate from this.
Until a little better consistency occurs, the forecast will trend
to the ridge building into eastern Washington and the Idaho
panhandle a little more each day, and thus warming temperatures a
few degrees each day. Precipitation chances remain near nil,
except for early Saturday where a lingering shower or thunderstorm
may occur over Idaho panhandle. ty
&&
.AVIATION...
12Z TAFS: Negatively tilted trof passage keeps aviation area wet
and unsettled today with MVFR ceilings at most TAF sites. Some
improvement as far as decreasing showers and raising of ceilings
expected after 03Z Tuesday. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 67 53 66 52 73 54 / 90 80 80 50 20 10
Coeur d`Alene 66 55 66 52 73 53 / 100 80 80 50 20 20
Pullman 66 52 66 51 74 52 / 70 60 70 50 20 10
Lewiston 71 57 74 57 80 58 / 70 60 60 60 30 20
Colville 71 54 70 51 75 52 / 100 70 80 60 20 20
Sandpoint 66 54 67 51 71 52 / 100 80 90 60 30 20
Kellogg 63 52 63 51 69 52 / 80 80 80 50 30 20
Moses Lake 74 58 69 56 80 58 / 50 30 50 20 20 10
Wenatchee 74 57 69 57 79 60 / 50 30 50 20 20 10
Omak 73 56 70 53 77 54 / 70 50 60 30 20 20
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
702 AM CDT MON JUN 24 2013
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 415 AM CDT MON JUN 24 2013
06Z DATA ANALYSIS HAD LOW PRESSURE OVER LK WINNIPEG AND OVER THE
OK/TX PANHANDLE AREA...WITH A WEAK RIDGE OF HIGH PRESSURE IN BETWEEN
ACROSS SD TO IA. FRONTAL BOUNDARY/TROUGH FROM THE TX/OK LOW WAS
ACROSS KS TO NORTHERN MO. WARM/MOISTURE ADVECTION/THETA-E
CONVERGENCE OVER THIS BOUNDARY FOCUSED FROM EASTERN CO TO SOUTHERN
IA...WHERE CONVECTION WAS FIRING EARLY THIS MORNING. THE FCST AREA
AND REST OF WI/MN GETTING A NEEDED BREAK FROM THE SHRA/TSRA SO FAR
SUNDAY THRU THIS MORNING...BEING NORTH/EAST OF THE SFC-700MB RIDGE
AXIS.
INITIALIZATIONS OF 24.00Z MODELS BETTER THAN THE PAST COUPLE 00Z
CYCLES...THIS EXCEPT FOR THE GFS TOO HIGH ON SFC DEW POINTS OVER
MUCH OF THE MID/UPPER MS VALLEY. EVEN WITH TIGHTER/BETTER
INITIALIZATIONS...SOLUTIONS CONTINUE TO HAVE MESO-SCALE DIFFERENCES
WHICH IMPACT THE SENSIBLE WEATHER IN THE SHORT TERM. DPROG/DT OF
500MB HGTS AT 24.00Z SHOWED THE MODEL RUNS OF 22.00Z AND 23.00Z
VERIFIED WELL ACROSS NOAM/EASTERN PAC...FAVORING STRONGER OF EARLIER
RUNS WITH THE TROUGH/ENERGY NEAR LK WINNIPEG AND THE TROUGHING OVER
CA. MODEL CONSENSUS REMAINS GOOD WITH THE LARGER SCALE FEATURES
TODAY THRU TUE BUT PLENTY OF DETAIL DIFFERENCES REMAIN WITH THE
WEAKER SHORTWAVES THRU THE SOUTHWEST FLOW OVER THE CENTRAL CONUS.
GENERAL TREND IS A LITTLE FLATTER WITH THE CENTRAL CONUS RIDGING AND
STRONGER WITH UNIDENTIFIABLE SHORTWAVE FEATURES. CHECK OF OBS VS.
MODEL DATA AT 06Z SHOWED ALL TO BE REASONABLE WITH THE SFC MASS
FIELDS OVER THE CENTRAL CONUS. PER WV IMAGERY MODELS LOOKED GOOD
WITH THE LARGER SHORTWAVES OVER NOAM...WHILE STRUGGLING WITH WHAT
LOOKED TO BE A WEAK SHORTWAVE AIDING THE NEB/CO/KS CONVECTION. AS
HAS BEEN THE CASE THE PAST FEW DAYS...MODELS HAVING DIFFICULTIES
WITH CONVECTION OVER THE CENTRAL CONUS. CLOSEST WITH THE 00-06Z
PRECIP LOOKED TO BE THE GFS AND THE HRRR WRF MODEL. NO ONE CLEAR
FAVORITE. WITH ALL THE MODEL SCENARIOS ON HOW CONVECTION PLAYS OUT
THE NEXT 48-72HRS AND MOST MODELS CONTINUING TO STRUGGLE WITH THAT
EARLY THIS MORNING...SHORT-TERM CONFIDENCE REMAINS BELOW AVERAGE.
FORECAST TODAY/TONIGHT HINGES ON WHERE THE KS/NORTHERN MO BOUNDARY
ENDS UP. MODEL CONSENSUS LIFTS THIS BOUNDARY...AND ITS FOCUS FOR
FORCING/LIFT/CONVECTION INITIATION...SLOWLY NORTH TODAY/TONIGHT...
TO SOUTHWEST MN TO EASTERN IA/NORTHWEST IL BY 12Z TUE. MOISTURE
TRANSPORT/THETA-E CONVERGENCE ON NOSE OF THE 850MB JET ALREADY
FIRING THE CONVECTION OVER IA...WITH THIS TRANSLATING EAST/NORTHEAST
TOWARD AND INTO THE SOUTHEAST END OF THE FCST AREA. WILL EXTEND THE
FLASH FLOOD WATCH FOR THE SOUTHEAST END OF THE FCST AREA THRU THE
MORNING.
LOW LEVEL MOISTURE TRANSPORT/THETA-E CONVERGENCE CONTINUES TO
INCREASE OVER THE FRONT AND TOWARD THE AREA TODAY AS LOW PRESSURE
LIFTS INTO NEB. GENERAL MODEL CONSENSUS FOR CONVECTION TO SLOWLY
BUILD WEST/SOUTH OF THE FCST AREA THIS MORNING THE LIFT INTO THE AREA
THIS AFTERNOON. PER THE HRRR...PART OF THIS IS THE COMPLEX MOVING
ACROSS NEB EARLY THIS MORNING. LEANING TOWARD THE HRRR WHICH HAS
BEEN DOING A DECENT JOB WITH THE CO/NEB CONVECTION AND THAT ACROSS
IA...THE NEB CONVECTION GROWS ONCE IT REACHES STRONGER/RICHER
MOISTURE TRANSPORT OVER EASTERN NEB/WESTERN IA. SOME FORM OF
CONVECTIVE COMPLEX THEN HEADS TOWARD THE FCST AREA FOR THE AFTERNOON.
LOW LEVEL THERMODYNAMIC FORCING STRENGTHENS INTO THE AREA TONIGHT
ALONG WITH THE MOISTURE TRANSPORT AS THE FRONT SLOWLY LIFTS NORTH.
RAISED SHRA/TSRA CHANCES INTO THE 60-70 PERCENT RANGE FOR TONIGHT
INTO TUE MORNING. ANY TSRA WILL REMAIN EFFICIENT RAIN MAKERS WITH PW
VALUES IN THE 1.5 TO 1.75 INCH RANGE...ML CAPES OF 2K-3K J/KG AND
WARM CLOUD DEPTHS OF 3.5 TO 4KM. WITH MANY AREAS WATERLOGGED AND
HAVING ONGOING FLOODING ISSUES...WILL EXPAND THE FLASH FLOOD WATCH
TO COVER ALL BUT CLARK/TAYLOR COUNTIES FOR THIS AFTERNOON THRU MID
MORNING TUE.
FORCING SIGNALS GET A LITTLE MORE MUDDIED TUE. THIS NOT UNEXPECTED
DUE TO POTENTIAL DIFFERENT OUTCOMES WITH CONVECTION OVER THE UPPER
MIDWEST TONIGHT. APPEARS THE FRONT WILL REMAIN SOUTH OF THE FCST
AREA WITH THE 925-850MB FLOW CONTINUING TO PUSH/LIFT MOISTURE
NORTHWARD OVER IT. CONTINUED 40-60 PERCENT SHRA/TSRA CHANCES OVER
MUCH OF THE FCST AREA TUE. MAY NEED TO EXTEND THE FLASH FLOOD WATCH
THRU TUE INTO TUE NIGHT...BUT WILL DEAL WITH THAT ONCE WE GET PAST
TONIGHT.
ON TOP OF THE HEAVY RAIN CONCERNS...A FEW OF THE TSRA COULD BE
SEVERE THIS AFTERNOON/EVENING AND AGAIN TUE INTO TUE EVENING DUE
TO THE STRONG INSTABILITY...INCREASE OF THE 0-6KM SHEAR AND
POTENTIAL FOR TSRA TO ORGANIZE INTO COMPLEXES WITH STRONG COLD
POOLS. SEE SWODY1 AND SWODY2 FOR MORE DETAILS.
USED A BLEND OF THE NUMERICAL TEMP GUIDANCE FOR HIGHS/LOWS FOR
TODAY THRU TUE.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 415 AM CDT MON JUN 24 2013
FOR TUE NIGHT THRU WED NIGHT MODELS SHOW THE REMNANTS OF THE
TROUGHING NOW OVER CA WILL LIFT INTO AND ACROSS THE UPPER MIDWEST.
TREND CONTINUES TO FAVOR STRONGER OF THE EARLIER RUNS. WITH THIS
BEING A LARGER SCALE FEATURE AND THE DECENT MODEL CONSISTENCY FCST
CONFIDENCE FOR THIS PERIOD IS AVERAGE.
AS THE STRONGER MID LEVEL TROUGH MOVES INTO THE UPPER MIDWEST TUE
NIGHT THE PLAINS SFC LOW MOVES INTO MN/WI. LOWER LEVEL THERMO
DYNAMIC FORCING/LIFT AND MOISTURE TRANSPORT REMAINS STRONG INTO THE
AREA AHEAD OF THESE FEATURES. WHERE THE FRONT AHEAD OF THE LOW FROM
TODAY/TUE ENDS UP WILL DETERMINE WHERE THE STRONGER LIFT WILL BE.
MODEL CONSENSUS HAS IT SOMEWHERE OVER THE FCST AREA TUE NIGHT...
THUS CARRIED HIGHEST SHRA/TSRA CHANCES IN THE 60-70 PERCENT RANGE
OVER THE NORTHEAST 2/3 OF THE FCST AREA. PW VALUES REMAIN IN THE 1.5
TO 1.75 INCH RANGE WITH ANY STORMS CAPABLE OF PRODUCING HEAVY RAINS.
AGAIN...WILL LIKELY NEED MORE FLASH FLOOD WATCHES FOR PORTIONS OF
THE AREA INTO TUE NIGHT WITH POTENTIAL FOR ANOTHER 0.5 TO 1.5
INCHES...LOCALLY MORE...OF RAIN.
ONCE THIS STRONGER MID LEVEL TROUGH PASSES TUE NIGHT/WED MORNING THE
FLOW PATTERN OVER NOAM BEGINS TO CHANGE WITH RIDGING BUILDING OVER
THE WESTERN CONUS AND INCREASING NORTHWEST FLOW ALOFT OVER THE
UPPER MIDWEST. DRIER AIR AND HIGH PRESSURE WILL SLOWLY SPREAD INTO
MN/IA/WI WED/WED NIGHT. SHRA/TSRA CHANCES WILL LINGER WED WITH THE
SFC LOW-MID LEVEL TROUGH OVER THE REGION. SHRA/TSRA CHANCES
DECREASE WED NIGHT AS HGTS RISE AND THE SFC-MID LEVEL LOW/TROUGH
MOVE EAST OF THE AREA.
DUE TO THE CONVECTION DETAIL UNCERTAINTIES...CONTINUED TO USE THE
MODEL/ENSEMBLE CONSENSUS FOR LOWS/HIGHS IN THE TUE NIGHT TO WED
NIGHT PERIOD.
ONCE AGAIN NOT A LOT OF TIME SPENT LOOKING AT THE DAY 4-7 PERIOD.
24.00Z MEDIUM RANGE MODELS MAINTAIN A GOOD CONSENSUS FOR THE
BUILDING WESTERN NOAM RIDGING AND EASTERN NOAM TROUGHING IN THE THU-
SUN PERIOD...WHICH PUTS THE REGION UNDER INCREASING NORTHWEST FLOW
ALOFT. THU-SUN SHAPING UP TO BE A DRIER PERIOD WITH TEMPERATURES
COOLING TO NEAR OR A BIT BELOW NORMAL. FCST CONFIDENCE FOR THIS
PERIOD LOOKS TO BE AVERAGE TO GOOD.
DRIER HIGH PRESSURE BUILDS IN FOR THU-SUN...BUT PLENTY OF RESIDUAL
LOW LEVEL MOISTURE AND MAXIMUM EVAPO-TRANSPIRATION FROM WELL WATERED
VEGETATION AND WET SOILS APPEAR TO REMAIN...ALONG WITH STEEP LOW/
MID LEVEL LAPSE RATES AND SHORTWAVES RIPPLING THRU THE NORTHWEST
FLOW ALOFT. THU-SUN TRENDING TO BE DRY DAYS BUT SOME SMALLER
MAINLY DIURNAL SHRA/TSRA CHANCES TO PERSIST...AIDED BY THE PASSING
SHORTWAVES FROM TIME TO TIME. MODEL/ENSEMBLE CONSENSUS FOR HIGHS/
LOWS IN THE DAY 4-7 PERIOD LOOK WELL TRENDED FOR NOW.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 702 AM CDT MON JUN 24 2013
SHOWERS AND THUNDERSTORMS WILL MOVE INTO THE REGION LATE THIS
AFTERNOON AS A WARM FRONT LIFTS INTO NORTHERN IOWA/SOUTHERN
WISCONSIN. PLAN ON SHOWERS AND STORMS IMPACTING THE TAF SITES
THROUGH THE EVENING HOURS INTO EARLY TUESDAY MORNING. THE RAIN MAY
BECOME HEAVY AT TIMES. A FEW THUNDERSTORMS MAY PRODUCE GUSTY
WINDS...ESPECIALLY LATE THIS AFTERNOON INTO THE EVENING HOURS.
VISIBILITIES WILL BE REDUCED TO 3SM IN THE HEAVIER THUNDERSTORMS.
OTHERWISE...PLAN ON VFR/MVFR CONDITIONS BEFORE THE STORMS MOVE IN
WITH CLOUD BASES IN THE 3000 TO 4000 FT RANGE.
&&
.HYDROLOGY...
ISSUED AT 415 AM CDT MON JUN 24 2013
THE THREAT FOR HEAVY RAINS CONTINUES/RETURNS TODAY AS YET ANOTHER
LOW LIFTS INTO THE CENTRAL PLAINS AND MOISTURE TRANSPORT INCREASES
INTO THE AREA. A FRONT SLOWLY LIFTING NORTH FROM KS/NORTHERN MO WILL
BE THE FOCUS FOR LIFT AND GENERATING TSRA TODAY/TONIGHT/TUE. THIS
BOUNDARY EXPECTED TO REMAIN SOUTH OF THE AREA THRU TUE...WITH THE
ZONE OF STRONGER LIFT REMAINING CLOSE TO OR OVER THE FCST AREA.
THUNDERSTORMS WILL CONTINUE TO BE EFFICIENT RAIN PRODUCERS. RAINFALL
AMOUNTS THIS AFTERNOON AND TONIGHT COULD RANGE FROM 0.50 TO 1.50
INCHES...WITH LOCALLY HIGHER AMOUNTS POSSIBLE. SINCE MUCH OF THE
AREA HAS SEEN ANYWHERE FROM 2 TO 10 INCHES DURING THE LAST 3 TO 4
DAYS...IT WILL NOT TAKE MUCH RAIN TO PRODUCE MORE FLOODING PROBLEMS.
ADDITION FLASH FLOODING IS QUITE POSSIBLE ACROSS PARTS OF THE
FORECAST AREA TODAY THRU TUE NIGHT. HOWEVER THERE CONTINUES TO BE
MUCH UNCERTAINTY ON WHERE THIS RAIN MAY FALL. CONTINUED THE FLASH
FLOOD WATCH FOR THE SOUTHEAST END OF THE FCST AREA THIS MORNING
THEN ISSUED A BROADER FLASH FLOOD WATCH FOR ALL BUT CLARK/TAYLOR
COUNTIES THIS AFTERNOON THROUGH MID MORNING TUE. APPEARS ANOTHER
ROUND OF WIDESPREAD CONVECTION IS POSSIBLE TUE NIGHT/WED MORNING
AND ADDITIONAL FLASH FLOOD WATCHES ARE LIKELY FOR THOSE PERIODS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FLASH FLOOD WATCH FROM NOON CDT TODAY THROUGH TUESDAY MORNING
FOR WIZ032>034-041>044-053.
FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR WIZ054-055-061.
MN...FLASH FLOOD WATCH FROM NOON CDT TODAY THROUGH TUESDAY MORNING
FOR MNZ079-086>088-094>096.
IA...FLASH FLOOD WATCH FROM NOON CDT TODAY THROUGH TUESDAY MORNING
FOR IAZ008>010-018-019.
FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR IAZ011-029-030.
&&
$$
SHORT TERM...RRS
LONG TERM....RRS
AVIATION...WETENKAMP
HYDROLOGY....RRS
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
649 AM CDT MON JUN 24 2013
UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND TUESDAY
ISSUED AT 444 AM CDT MON JUN 24 2013
THE CONTINUING SAGA ON WHERE AND WHEN FOR CONVECTION CONTINUES THIS
MORNING. LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY HINT AT
WEAK BOUNDARY OVER NORTHEAST WI SEEN IN DEW POINTS. AREA OF
DISORGANIZED TSTMS MOVING NORTH THROUGH IA AND WESTERN IL.
STARTING TO SEE MORE MOVEMENT TO EAST OVER IL IN LATEST SCANS WHICH
WOULD GO WITH MODELS PROJECTION OF LLVL JET SHIFTING MORE TO THE
WEST AND WEAKENING BY 12Z.
HRRR SEEMS TO HAVE BEST HANDLE ON CURRENT TRENDS...SHOWING ONLY
SPOTTY CONVECTION OVER CWA TODAY MAINLY OVER THE SOUTH HALF.
ALL MODELS STILL SHOWING VARIETY OF SOLUTIONS IN QPF PATTERN
THROUGH THIS PERIOD. HAVE TRENDED TOWARD NAM TODAY GIVEN DRIER
AIR WORKING IN AS SEEN IN SIG DROP IN PWATS ON MSP SOUNDING LAST
EVENING. SFC BASED INSTABILITY STILL SIG 1-2K...THOUGH NOT SEEING
ANY REAL TRIGGER/LIFT TODAY. WENT WITH SLIGHTS FOR LATE DAY
CONVECTION SOUTH AND EAST ALONG LAKE BREEZE BOUNDARY.
FORCING AND MOISTURE WORKS BACK INTO THE AREA THIS EVENING WITH
STRENGTHENING LLVL FLOW POINTING INTO SOUTHWEST WI AFTER
06Z. ALSO SEEING SOME SUPPORT FROM RRQ OF JET MAX MOVING THROUGH
LAKE SUPERIOR REGION. WILL GO WITH INCREASING CHANCE POPS TONIGHT
HIGH CHANCE POPS TUE AS FGEN/ISENTROPIC LIFT MAXIMIZED OVER CWA
FROM 12Z TO 18Z TUES. CWA REMAINS IN SLIGHT RISK AREA ON TUE.
SHEAR BETTER SOUTH FOR SOME WIND CONCERNS. WBZERO HGTS RATHER
HIGH FOR LARGE HAIL. WITH PWATS RETURNING TO 1.5 TO 2 INCHES AGAIN
HEAVY RAIN MORE OF CONCERN.
.LONG TERM...TUESDAY NIGHT THROUGH SUNDAY
ISSUED AT 444 AM CDT MON JUN 24 2013
500MB RIDGE EXPECTED TO BUILD ACROSS THE WESTERN UNITED STATES
WHILE UPPER TROUGH DEEPENS AND POSSIBLY CLOSES OFF ACROSS THE
WESTERN GREAT LAKES BY THE END OF THE WORK WEEK INTO NEXT WEEKEND.
FORECAST ISSUES ALREADY AT THE START OF THE PERIOD TUESDAY NIGHT.
HAVE CONCERNS ON THE PLACEMENT OF CONVECTION TUESDAY EVENING ACROSS
NORTHERN WISCONSIN. BELIEF IS THAT THE AXIS OF HEAVIER PRECIPITATION
TOO FAR NORTH. THINK BAND WILL BE FURTHER SOUTH AS FIRST COMPLEX OF
STORMS LATE MONDAY NIGHT AND TUESDAY WILL PUSH AN OUTFLOW BOUNDARY
SOUTHWARD THAN WHAT THE MODELS SHOW...SIMILAR TOO WHAT HAPPENED A
FEW DAYS AGO. GFS QPF FIELD SEEMS REASONABLE BASED ON MY CURRENT
THINKING. THIS COULD AFFECT THE RAIN CHANCES ACROSS THE NORTH
TUESDAY EVENING. SOUTHERN SECTIONS OF THE FORECAST AREA WILL BE
CLOSE ENOUGH TO STILL WARRANT LIKELY CHANCES. 500MB TROUGH SWINGS
INTO THE AREA TOWARDS 12Z WEDNESDAY...WARRANTING LIKELY POPS EVEN
ACROSS THE NORTH. UPPER TROUGH WILL SWING ACROSS THE AREA ON
WEDNESDAY. RAISED POPS TO 50 TO 55 PERCENT...AND MAY BUMP THEM
UP A LITTLE MORE BEFORE FORECAST ISSUANCE. THE UPPER TROUGH
SHOULD SWING EAST INTO LOWER MICHIGAN WEDNESDAY NIGHT. THERE WILL
STILL BE SOME LINGERING EVENING SHOWERS AND A FEW STORMS. MID
LEVEL LAPSE RATES NOT IMPRESSIVE...THEREFORE ONLY EXPECTED ISOLATED
NATURE OF ANY THUNDERSTORMS WEDNESDAY EVENING.
NORTHWEST FLOW ALOFT WILL CONTINUE THURSDAY AND FRIDAY...ALTHOUGH
A DEEPER 500MB TROUGH WILL SWING ACROSS THE AREA FRIDAY AFTERNOON AND
FRIDAY NIGHT. WILL CONTINUE THE SMALL CHANCES FOR SHOWERS SATURDAY...
BUT NOT TOO OPTIMISTIC WE WOULD SEE THEM AT THIS TIME SINCE UPPER
TROUGH WILL WELL EAST OF THE AREA WITH BUILDING HEIGHTS. CANADIAN
HIGH PRESSURE WILL DOMINATE THE WEATHER PATTERN ON SUNDAY...ALTHOUGH
COULD NOT RULE OUT A FEW ISOLATED SHOWERS SUNDAY AFTERNOON.
FOR THE MOST PART...VERIFICATION DATA HAS SHOWN WE AND NUMERICAL
GUIDANCE HAS BEEN TOO WARM OF LATE. DID NUDGE TEMPERATURES DOWN A
DEGREE OR TWO MOST PERIODS. WILL NEED TO WATCH WEDNESDAY...IF IT
STAYS CLOUDY AND THERE IS A LOT OF RAIN AROUND DURING THE DAY...
TEMPERATURES COULD STAY IN THE 70S.
&&
.AVIATION...FOR 12Z TAF ISSUANCE
ISSUED AT 641 AM CDT MON JUN 24 2013
WILL CONTINUE TO DEAL WITH WHEN AND WHERE SHOWERS AND
THUNDERSTORMS WILL BREAK OUT. WESTERLY FLOW AND DRIER AIR ALOFT
WILL EXPECTED TO LEAD TO MOSTLY DRY DAY...THOUGH STILL RATHER
HUMID AND UNSTABLE AT LOW LEVELS SO MAY SEE POSSIBLE CONVECTIVE
DEVELOPMENT ALONG ANY WEAK BOUNDARIES DURING THE AFTERNOON LIKE
LAKE BREEZE BOUNDARY. BEST ESTIMATE RIGHT NOW IS THAT SOME
CONVECTION WILL FIRE MONDAY NIGHT...AS A UPPER DISTURBANCE TRACKS
THROUGH THE AREA AND A SOUTHWESTERLY LOW-LEVEL JET REDEVELOPS.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....TE
LONG TERM......ECKBERG
AVIATION.......TE
AREA FORECAST DISCUSSION
NWS ALBANY NY
450 PM EDT MON JUN 24 2013
.SYNOPSIS...
VERY WARM AND HUMID CONDITIONS WILL CONTINUE EARLY THIS WEEK WITH
THE THREAT OF SHOWERS AND THUNDERSTORMS MAINLY DURING THE AFTERNOON
AND EVENING HOURS. STORMS WILL HAVE THE POTENTIAL TO PRODUCE LOCALLY
HEAVY RAINFALL. OUR NIGHTS WILL BE CONTINUE TO BE MUGGY WITH PATCHY
FOG. MORE PERSISTENT CHANCES FOR SHOWERS AND THUNDERSTORMS ARE
EXPECTED LATER IN THE WEEK INTO THE WEEKEND AS A SLOW MOVING LOW
PRESSURE SYSTEM IMPACTS THE REGION.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
AS OF 955 AM...ANOTHER HAZY...HOT AND HUMID DAY SHAPING UP. 12Z ALY
SOUNDING SHOWS PLENTY OF ENERGY FOR AFTERNOON THUNDERSTORMS. WATER
VAPOR LOOP SHOWS CLOSED LOW SPINNING OVER WESTERN PENNSYLVANIA.
THIS UPPER LEVEL LOW IS EXPECTED TO MOVE OVER THE SOUTHERN PART OF
THE ALBANY FORECAST AREA OVER THE NEXT 12-18 HOURS AND SHOULD BE A
FOCUS FOR STORMS. PWAT ON 12Z ALY SOUNDING WAS 1.77 INCHES SO
COPIOUS MOISTURE FOR HEAVY RAINERS. PIT 12Z SOUNDING...UNDER UPPER
LEVEL LOW...HAS STEEPER LAPSE RATES. 12Z HRRR SHOWING A MORE
WIDESPREAD THREAT OF AFTERNOON STORMS. WILL HAVE TO MONITOR FOR
LATER FLASH FLOOD WATCH IF LARGE AREA OF HEAVY RAIN DEVELOPS.
COULD BE AN EXCITING DAY...
PREVIOUS...
THE RIDGE WILL WEAKEN A TAD TODAY AS THE REMNANTS OF THE UPPER
LOW FROM OVER THE TENNESSEE VALLEY MOVES EASTWARD. THIS WILL BE
THE MAIN FEATURE TRIGGERING CONVECTION ACROSS THE AREA TODAY AND
IT WILL ACCOMPANY THE HEATING OF THE DAY. MODEL GUIDANCE SUGGESTS
CAPE VALUES OF PEAKING AT 1000-2000 J/KG WITH DEW POINTS IN THE
MID TO UPPER 60S. LAPSE RATE OF 6 TO 6.5 C/KM ARE EXPECTED THIS
AFTERNOON WITH THE GFS INDICATING 7 C/KM POSSIBLE. MEAN FLOW IS
RATHER WEAK AT 15 TO 20 KNOTS SO STORMS WILL MOVE RATHER SLOWLY
AND CONVECTION WILL BE LOOSELY ORGANIZED. THE STORM PREDICTION
CENTER HAS THE AREA/REGION IN THE GENERAL THUNDERSTORM OUTLOOK FOR
TODAY AND TONIGHT. FREEZING LEVEL IS HIGH JUST OVER 14000 FEET ON
THE 00Z/MON ALY SOUNDING...SO SOME STORMS WILL PRODUCE LOCALLY
HEAVY RAINFALL. THIS ALONG WITH THE RATHER SLOW MOVEMENT HAVE
ADDED ENHANCED WORDING OF HEAVY RAINFALL TO THE FORECAST AND WILL
KEEP MENTION IN THE HAZARDOUS WEATHER OUTLOOK. CONVECTION IS
EXPECTED TO DIMINISH THIS EVENING AS THE WEAKENING UPPER
LOW/TROUGH MOVES OFF TO THE EAST AND WITH THE LOSS OF DAYTIME
HEATING.
LOOKING AT TEMPERATURES IN THE 80S WITH AROUND 90 DEGREES UP THE
HUDSON VALLEY INTO CAPITAL DISTRICT. DEW POINTS WILL BE IN THE MID
TO UPPER 60S MAKING IT FELL EVEN HOTTER. HEAT INDICES SHOULD REACH
THE MID 90S UP THE HUDSON RIVER VALLEY.
ANOTHER MUGGY NIGHT WITH LOWS AND DEW POINTS IN THE 60S. WINDS WILL
BECOME LIGHT TO CALM WINDS. HAVE ADDED PATCHY FOG MAINLY IN THE
RIVER VALLEY LOCATIONS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
BY TUESDAY MORNING FLOW WILL BECOME NEARLY ZONAL ACROSS THE REGION.
A WEAKENING SURFACE LOW AND MID LEVEL SHORT WAVE TROUGH WILL MOVE
EASTWARD ACROSS SOUTHERN CANADA PASSING WELL TO OUR NORTH TUESDAY.
PLUS GUIDANCE INDICATES SMALL PIECES OF ENERGY SHOULD MOVE THROUGH
THE FLOW FARTHER SOUTH ACROSS OUR REGION.ALL THIS LEADS TO ANOTHER
ROUND OF CONVECTION MAINLY DURING THE AFTERNOON AND EVENING HOURS
TUESDAY WITH THE HEATING OF THE DAY. THE BETTER DYNAMICS AND SHEAR
WILL BE ACROSS NORTHERN NEW YORK INTO NORTHERN NEW ENGLAND AND THIS
IS WHERE THE STORM PREDICTION CENTER HAS GONE WITH A SLIGHT RISK FOR
SEVERE THUNDERSTORMS. FARTHER SOUTH ACROSS OUR FORECAST AREA MEAN
FLOW WILL STILL BE RATHER WEAK AROUND 20 KNOTS. IT WILL BE ANOTHER
HOT DAY SIMILAR TO MONDAY IN TEMPERATURES AND HEAT INDICES.
A WEAK FRONTAL BOUNDARY WILL BE BROUGHT SOUTHWARD INTO THE REGION
TUESDAY NIGHT...HOWEVER DUE TO THE FLOW ALOFT THE BOUNDARY WILL
STALL ACROSS THE REGION. A MORE VIGOROUS SHORT WAVE WILL MOVE INTO
THE LONGWAVE TROUGH OVER THE GREAT LAKES REGION WEDNESDAY AND
WEDNESDAY NIGHT AND HEIGHTS WILL BEGIN TO FALL. CHANCES FOR
CONVECTION WILL NOT BE LIMITED MAINLY TO THE AFTERNOON AND EVENING
HOURS THIS TIME. AS HEIGHTS CONTINUE TO FALL WILL HAVE LARGE SCALE
ASCENT THE BOUNDARY WILL BEGIN TO MOVE BACK NORTHWARD AS A WARM
FRONT.
PRECIPITABLE WATER VALUES WILL STILL BE HIGH SO LOCALLY HEAVY
RAINFALL IS EXPECTED WITH SOME STORMS...SO HAVE MENTIONED IN OUR
HAZARDOUS WEATHER OUTLOOK.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AN UNSETTLED AND WET EXTENDED FORECAST IS LIKELY ACROSS NY AND NEW
ENGLAND WITH PERSISTENT CHANCES OF SHOWERS AND THUNDERSTORMS...AS A
MID AND UPPER LEVEL TROUGH WILL INITIALLY IMPACT THE REGION TO CLOSE
THE WEEK...AND THEN IT MAY CLOSE OR CUT OFF NEAR THE GREAT LAKES
REGION AND SRN ONTARIO FOR THE WEEKEND.
THE LATEST GFS/ECMWF/CANADIAN GGEM/ENSEMBLE GUIDANCE AND HPC
GRAPHICS ARE IN PRETTY GOOD AGREEMENT FOR AN ACTIVE STRETCH OF
WEATHER. THEIR ARE SOME SUBTLE DIFFERENCES FOR THE TIMING OF THE
SHORT-WAVE IMPULSE ROTATING THROUGH THE UPPER LEVEL TROUGH...BUT ALL
AN ALL...IT IS EXTREMELY DIFFICULT TO FIND A SUSTAINED DRY STRETCH
OF WX TO CLOSE JUNE.
THU-FRI...A WAVE OF LOW PRESSURE APPROACHES THE FCST AREA FROM THE
GREAT LAKES REGION WITH SOME OVER RUNNING SHOWERS AND THUNDERSTORMS
AHEAD OF A WARM FRONT. THE WARM FRONT MAY BUST THROUGH PORTIONS OF
THE FCST AREA FOR A POTENTIAL OF STRONG THUNDERSTORMS...IF HEATING
IS REALIZED. THE DETAILS ARE NEBULOUS AND MURKY...SO WE WILL CALL
IT A CHANCE OF SHOWERS AND THUNDERSTORMS...THU INTO THU NIGHT. A
S/SW H850 LLJ OF 30-45 KTS WILL TRANSPORT IN SOME GULF
MOISTURE...AND PWATS WILL CONTINUE TO RUN ABOVE NORMAL. THE SFC LOW
BEGINS TO OCCLUDE AND CLOSE OFF JUST NORTHWEST OF LAKE ONTARIO AND
NRN NY ON FRI. THE GFS CONTINUES TO PAINT MODERATE AMOUNTS OF
INSTABILITY FOR THE POTENTIAL OF SHOWERS AND THUNDERSTORMS AGAIN.
THE SUBTROPICAL HIGH REMAINS ANCHORED DOWNSTREAM CONTINUING A DEEP
S/SW FETCH OF MOISTURE. THIS LONG DURATION STRETCH OF WX...BEGINS
TO MATERIALIZE INTO POTENTIALLY A CLASSIC GREAT LAKES CSTAR CUTOFF
LOW WARM SEASON EVENT. TEMPS LOOK TO RUN SLIGHTLY BELOW TO NEAR
NORMAL FOR THE THESE DAYS WITH HIGHS IN THE M70S TO L80S AND LOWS IN
THE U50S TO 60S.
SAT-MON...THE LONGWAVE TROUGH BEGINS TO AMPLIFY WITH THE EMBEDDED
500 HPA CLOSED CIRCULATIONS OVER THE CNTRL AND ERN GREAT LAKES. A
COLD FRONT BEGINS TO STALL OUT NEAR THE ERN CONUS SEABOARD.
MULTIPLE SHORT-WAVES LIFT NORTHWARD ON THE EAST SIDE OF TROUGH.
PERSISTENT BANDS OF SHOWERS AND THUNDERSTORMS TIMED TO THE DIURNAL
HEATING AND THE PROPAGATION OF THE IMPULSES ARE POSSIBLE FOR THE
WEEKEND INTO EARLY NEXT WEEK. THEIR IS A SMALL POSSIBILITY THAT
DRYING IN THE WAKE OF DISTURBANCES MAY PROMOTE MINI DRY STRETCHES.
AGAIN...THIS APPEARS TO FIT A GREAT LAKES WARM SEASON CSTAR
CLOSED/CUTOFF SCENARIO FOR AN EXTENDED PERIOD OF SHOWERS AND
THUNDERSTORMS. THE WEEKEND IS DOMINATED BY A POSITIVE TILT
SCENARIO...PERHAPS SHIFTING NEUTRAL BY EARLY NEXT WEEK. H850 TEMPS
CONTINUE TO BE IN THE +14C TO +16C RANGE WITH LIMITED HEATING EACH
DAY WITH A RESIDUAL COLD POOL ALOFT...AND THE ACTIVE S/SW FLOW.
EXPECT HIGHS TO CONTINUE IN THE 70S TO L80S WITH LOWS IN THE U50S TO
60S. TOO EARLY TO PINPOINT LOCATIONS...BUT SOME HYDRO PROBLEMS COULD
MATERIALIZE...IF LOCATIONS GET REPEATEDLY HIT BY BANDS OF SHOWERS
AND THUNDERSTORMS.
&&
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
AS OF 445 PM EDT...MOST OF THE THUNDERSTORMS HAVE STAYED AWAY FROM
THE TAF SITES. ONCE BRUSHED KALB/KGFL...ONE IS JUST NORTH OF KPOU.
IT LOOKS AS IF ONE CELL MIGHT HIT KPSF SO AMENDED TO INCLUDE A TEMPO
FOR MVFR THUNDER 21-22Z.
STILL MORE THUNDERSTORMS UPSTREAM ALTHOUGH OVERALL THE TREND HAS
WEAKENED SLIGHTLY BUT STILL PLENTY OF INSTABILITY TO WORK WITH...NOT
OUT OF THE WOODS YET. EXCEPT FOR KPSF WILL CONTINUE WITH GENERAL
VCSH BUT THAT COULD CHANGE AT ANY TIME THROUGH 00Z. STAY TUNED AND
KEEP CHECKING THE TAFS AND AVIATION DISCUSSION.
AFTER WE LOOSE THE CELLS THIS EVENING...CONCERNS FOCUS TO FOG
ISSUES...ESPECIALLY AT KGFL WHERE BELIEVE IT WILL HAPPEN. ELSEWHERE
WENT WITH MVFR FOG.
THE WINDS TODAY WILL BE FROM A WESTERLY DIRECTION AT 5-10 KNOTS
WITH OCCASIONAL GUST TO 15 KNOTS. EXPECT THE WINDS TO BECOME LIGHT TO
CALM IN THE EARLY EVENING AND REMAIN LIGHT THROUGH TUESDAY.
OUTLOOK...
TUE...MAINLY VFR. CHC -TSRA/-SHRA MAINLY DURING THE AFTN INTO THE
EVNG. MVFR-IFR FOG LATE AT NIGHT INTO EARLY IN THE MORNING.
WED...MAINLY VFR. SLIGHT CHC -TSRA/-SHRA.
THU-FRI...VFR/MVFR. CHC -TSRAS/-SHRAS.
&&
.FIRE WEATHER...
VERY WARM AND HUMID CONDITIONS WILL CONTINUE EARLY THIS WEEK WITH
THE THREAT OF SHOWERS AND THUNDERSTORMS MAINLY DURING THE AFTERNOON
AND EVENING HOURS. STORMS WILL HAVE THE POTENTIAL TO PRODUCE LOCALLY
HEAVY RAINFALL. OUR NIGHTS WILL BE CONTINUE TO BE MUGGY WITH PATCHY
FOG. MORE PERSISTENT CHANCES FOR SHOWERS AND THUNDERSTORMS ARE
EXPECTED LATER IN THE WEEK INTO THE WEEKEND AS A SLOW MOVING LOW
PRESSURE SYSTEM IMPACTS THE REGION.
&&
.HYDROLOGY...
INCREASING UNSETTLED WEATHER THIS WEEK. EARLY IN THE WEEK THE
CHANCES OF SHOWERS AND THUNDERSTORMS WILL BE MAINLY DURING THE
AFTERNOON AND EVENING HOURS. HOWEVER...PERSISTENT CHANCES OF SHOWERS
AND THUNDERSTORMS ARE EXPECTED FOR THE LATER PART OF THE WEEK INTO
THE WEEKEND AS A MID/UPPER LEVEL TROUGH IMPACTS THE REGION.
STORMS WILL HAVE THE POTENTIAL TO PRODUCE LOCALLY HEAVY RAINFALL ALL
WEEK WITH HIGH PRECIPITABLE WATER VALUES. EARLY IN THE WEEK FLOW
ALOFT WILL BE RATHER LIGHT SO STORMS WILL BE SLOWER MOVERS. FLOW IS
EXPECTED TO INCREASE LATER IN THE WEEK. PONDING OF WATER ON ROADWAYS
ALONG WITH MINOR FLOODING OF LOW LYING AND POOR DRAINAGE AREAS WILL
BE POSSIBLE. PLUS SOME SMALL STREAMS...CREEKS...AND BROOKS MAY REACH
BANKFULL OR EVEN FLOODING QUICKLY IN THE HEAVY RAINFALL ASSOCIATED
WITH THE THUNDERSTORMS ESPECIALLY IF STORMS MOVE OVER THE SAME AREA
REPEATEDLY.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...BGM
NEAR TERM...BGM
SHORT TERM...BGM
LONG TERM...BGM
AVIATION...SND/HWJIV
FIRE WEATHER...BGM
HYDROLOGY...BGM
AREA FORECAST DISCUSSION
NWS ALBANY NY
148 PM EDT MON JUN 24 2013
.SYNOPSIS...
VERY WARM AND HUMID CONDITIONS WILL CONTINUE EARLY THIS WEEK WITH
THE THREAT OF SHOWERS AND THUNDERSTORMS MAINLY DURING THE AFTERNOON
AND EVENING HOURS. STORMS WILL HAVE THE POTENTIAL TO PRODUCE LOCALLY
HEAVY RAINFALL. OUR NIGHTS WILL BE CONTINUE TO BE MUGGY WITH PATCHY
FOG. MORE PERSISTENT CHANCES FOR SHOWERS AND THUNDERSTORMS ARE
EXPECTED LATER IN THE WEEK INTO THE WEEKEND AS A SLOW MOVING LOW
PRESSURE SYSTEM IMPACTS THE REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 955 AM...ANOTHER HAZY...HOT AND HUMID DAY SHAPING UP. 12Z ALY
SOUNDING SHOWS PLENTY OF ENERGY FOR AFTERNOON THUNDERSTORMS. WATER
VAPOR LOOP SHOWS CLOSED LOW SPINNING OVER WESTERN PENNSYLVANIA.
THIS UPPER LEVEL LOW IS EXPECTED TO MOVE OVER THE SOUTHERN PART OF
THE ALBANY FORECAST AREA OVER THE NEXT 12-18 HOURS AND SHOULD BE A
FOCUS FOR STORMS. PWAT ON 12Z ALY SOUNDING WAS 1.77 INCHES SO
COPIOUS MOISTURE FOR HEAVY RAINERS. PIT 12Z SOUNDING...UNDER UPPER
LEVEL LOW...HAS STEEPER LAPSE RATES. 12Z HRRR SHOWING A MORE
WIDESPREAD THREAT OF AFTERNOON STORMS. WILL HAVE TO MONITOR FOR
LATER FLASH FLOOD WATCH IF LARGE AREA OF HEAVY RAIN DEVELOPS.
COULD BE AN EXCITING DAY...
PREVIOUS...
THE RIDGE WILL WEAKEN A TAD TODAY AS THE REMNANTS OF THE UPPER
LOW FROM OVER THE TENNESSEE VALLEY MOVES EASTWARD. THIS WILL BE
THE MAIN FEATURE TRIGGERING CONVECTION ACROSS THE AREA TODAY AND
IT WILL ACCOMPANY THE HEATING OF THE DAY. MODEL GUIDANCE SUGGESTS
CAPE VALUES OF PEAKING AT 1000-2000 J/KG WITH DEW POINTS IN THE
MID TO UPPER 60S. LAPSE RATE OF 6 TO 6.5 C/KM ARE EXPECTED THIS
AFTERNOON WITH THE GFS INDICATING 7 C/KM POSSIBLE. MEAN FLOW IS
RATHER WEAK AT 15 TO 20 KNOTS SO STORMS WILL MOVE RATHER SLOWLY
AND CONVECTION WILL BE LOOSELY ORGANIZED. THE STORM PREDICTION
CENTER HAS THE AREA/REGION IN THE GENERAL THUNDERSTORM OUTLOOK FOR
TODAY AND TONIGHT. FREEZING LEVEL IS HIGH JUST OVER 14000 FEET ON
THE 00Z/MON ALY SOUNDING...SO SOME STORMS WILL PRODUCE LOCALLY
HEAVY RAINFALL. THIS ALONG WITH THE RATHER SLOW MOVEMENT HAVE
ADDED ENHANCED WORDING OF HEAVY RAINFALL TO THE FORECAST AND WILL
KEEP MENTION IN THE HAZARDOUS WEATHER OUTLOOK. CONVECTION IS
EXPECTED TO DIMINISH THIS EVENING AS THE WEAKENING UPPER
LOW/TROUGH MOVES OFF TO THE EAST AND WITH THE LOSS OF DAYTIME
HEATING.
LOOKING AT TEMPERATURES IN THE 80S WITH AROUND 90 DEGREES UP THE
HUDSON VALLEY INTO CAPITAL DISTRICT. DEW POINTS WILL BE IN THE MID
TO UPPER 60S MAKING IT FELL EVEN HOTTER. HEAT INDICES SHOULD REACH
THE MID 90S UP THE HUDSON RIVER VALLEY.
ANOTHER MUGGY NIGHT WITH LOWS AND DEW POINTS IN THE 60S. WINDS WILL
BECOME LIGHT TO CALM WINDS. HAVE ADDED PATCHY FOG MAINLY IN THE
RIVER VALLEY LOCATIONS.
&&
.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
BY TUESDAY MORNING FLOW WILL BECOME NEARLY ZONAL ACROSS THE REGION.
A WEAKENING SURFACE LOW AND MID LEVEL SHORT WAVE TROUGH WILL MOVE
EASTWARD ACROSS SOUTHERN CANADA PASSING WELL TO OUR NORTH TUESDAY.
PLUS GUIDANCE INDICATES SMALL PIECES OF ENERGY SHOULD MOVE THROUGH
THE FLOW FARTHER SOUTH ACROSS OUR REGION.ALL THIS LEADS TO ANOTHER
ROUND OF CONVECTION MAINLY DURING THE AFTERNOON AND EVENING HOURS
TUESDAY WITH THE HEATING OF THE DAY. THE BETTER DYNAMICS AND SHEAR
WILL BE ACROSS NORTHERN NEW YORK INTO NORTHERN NEW ENGLAND AND THIS
IS WHERE THE STORM PREDICTION CENTER HAS GONE WITH A SLIGHT RISK FOR
SEVERE THUNDERSTORMS. FARTHER SOUTH ACROSS OUR FORECAST AREA MEAN
FLOW WILL STILL BE RATHER WEAK AROUND 20 KNOTS. IT WILL BE ANOTHER
HOT DAY SIMILAR TO MONDAY IN TEMPERATURES AND HEAT INDICES.
A WEAK FRONTAL BOUNDARY WILL BE BROUGHT SOUTHWARD INTO THE REGION
TUESDAY NIGHT...HOWEVER DUE TO THE FLOW ALOFT THE BOUNDARY WILL
STALL ACROSS THE REGION. A MORE VIGOROUS SHORT WAVE WILL MOVE INTO
THE LONGWAVE TROUGH OVER THE GREAT LAKES REGION WEDNESDAY AND
WEDNESDAY NIGHT AND HEIGHTS WILL BEGIN TO FALL. CHANCES FOR
CONVECTION WILL NOT BE LIMITED MAINLY TO THE AFTERNOON AND EVENING
HOURS THIS TIME. AS HEIGHTS CONTINUE TO FALL WILL HAVE LARGE SCALE
ASCENT THE BOUNDARY WILL BEGIN TO MOVE BACK NORTHWARD AS A WARM
FRONT.
PRECIPITABLE WATER VALUES WILL STILL BE HIGH SO LOCALLY HEAVY
RAINFALL IS EXPECTED WITH SOME STORMS...SO HAVE MENTIONED IN OUR
HAZARDOUS WEATHER OUTLOOK.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AN UNSETTLED AND WET EXTENDED FORECAST IS LIKELY ACROSS NY AND NEW
ENGLAND WITH PERSISTENT CHANCES OF SHOWERS AND THUNDERSTORMS...AS A
MID AND UPPER LEVEL TROUGH WILL INITIALLY IMPACT THE REGION TO CLOSE
THE WEEK...AND THEN IT MAY CLOSE OR CUT OFF NEAR THE GREAT LAKES
REGION AND SRN ONTARIO FOR THE WEEKEND.
THE LATEST GFS/ECMWF/CANADIAN GGEM/ENSEMBLE GUIDANCE AND HPC
GRAPHICS ARE IN PRETTY GOOD AGREEMENT FOR AN ACTIVE STRETCH OF
WEATHER. THEIR ARE SOME SUBTLE DIFFERENCES FOR THE TIMING OF THE
SHORT-WAVE IMPULSE ROTATING THROUGH THE UPPER LEVEL TROUGH...BUT ALL
AN ALL...IT IS EXTREMELY DIFFICULT TO FIND A SUSTAINED DRY STRETCH
OF WX TO CLOSE JUNE.
THU-FRI...A WAVE OF LOW PRESSURE APPROACHES THE FCST AREA FROM THE
GREAT LAKES REGION WITH SOME OVER RUNNING SHOWERS AND THUNDERSTORMS
AHEAD OF A WARM FRONT. THE WARM FRONT MAY BUST THROUGH PORTIONS OF
THE FCST AREA FOR A POTENTIAL OF STRONG THUNDERSTORMS...IF HEATING
IS REALIZED. THE DETAILS ARE NEBULOUS AND MURKY...SO WE WILL CALL
IT A CHANCE OF SHOWERS AND THUNDERSTORMS...THU INTO THU NIGHT. A
S/SW H850 LLJ OF 30-45 KTS WILL TRANSPORT IN SOME GULF
MOISTURE...AND PWATS WILL CONTINUE TO RUN ABOVE NORMAL. THE SFC LOW
BEGINS TO OCCLUDE AND CLOSE OFF JUST NORTHWEST OF LAKE ONTARIO AND
NRN NY ON FRI. THE GFS CONTINUES TO PAINT MODERATE AMOUNTS OF
INSTABILITY FOR THE POTENTIAL OF SHOWERS AND THUNDERSTORMS AGAIN.
THE SUBTROPICAL HIGH REMAINS ANCHORED DOWNSTREAM CONTINUING A DEEP
S/SW FETCH OF MOISTURE. THIS LONG DURATION STRETCH OF WX...BEGINS
TO MATERIALIZE INTO POTENTIALLY A CLASSIC GREAT LAKES CSTAR CUTOFF
LOW WARM SEASON EVENT. TEMPS LOOK TO RUN SLIGHTLY BELOW TO NEAR
NORMAL FOR THE THESE DAYS WITH HIGHS IN THE M70S TO L80S AND LOWS IN
THE U50S TO 60S.
SAT-MON...THE LONGWAVE TROUGH BEGINS TO AMPLIFY WITH THE EMBEDDED
500 HPA CLOSED CIRCULATIONS OVER THE CNTRL AND ERN GREAT LAKES. A
COLD FRONT BEGINS TO STALL OUT NEAR THE ERN CONUS SEABOARD.
MULTIPLE SHORT-WAVES LIFT NORTHWARD ON THE EAST SIDE OF TROUGH.
PERSISTENT BANDS OF SHOWERS AND THUNDERSTORMS TIMED TO THE DIURNAL
HEATING AND THE PROPAGATION OF THE IMPULSES ARE POSSIBLE FOR THE
WEEKEND INTO EARLY NEXT WEEK. THEIR IS A SMALL POSSIBILITY THAT
DRYING IN THE WAKE OF DISTURBANCES MAY PROMOTE MINI DRY STRETCHES.
AGAIN...THIS APPEARS TO FIT A GREAT LAKES WARM SEASON CSTAR
CLOSED/CUTOFF SCENARIO FOR AN EXTENDED PERIOD OF SHOWERS AND
THUNDERSTORMS. THE WEEKEND IS DOMINATED BY A POSITIVE TILT
SCENARIO...PERHAPS SHIFTING NEUTRAL BY EARLY NEXT WEEK. H850 TEMPS
CONTINUE TO BE IN THE +14C TO +16C RANGE WITH LIMITED HEATING EACH
DAY WITH A RESIDUAL COLD POOL ALOFT...AND THE ACTIVE S/SW FLOW.
EXPECT HIGHS TO CONTINUE IN THE 70S TO L80S WITH LOWS IN THE U50S TO
60S. TOO EARLY TO PINPOINT LOCATIONS...BUT SOME HYDRO PROBLEMS COULD
MATERIALIZE...IF LOCATIONS GET REPEATEDLY HIT BY BANDS OF SHOWERS
AND THUNDERSTORMS.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
POP UP AFTERNOON THUNDERSTORMS DOT THE RADAR SCOPE. PROBABILITY OF
ANY ONE STORM HITTING A TAF SITE IS STILL LESS THAN 30 PERCENT.
WE`LL CONTINUE TO MONITOR AND SEE IF ANY CLUSTERS OF STORMS
DEVELOP WHICH MAY MOVE TOWARD ANY PARTICULAR TAF SITE.
THE WINDS TODAY WILL BE FROM A WESTERLY DIRECTION AT 5-10 KNOTS
WITH OCCASIONAL GUST TO 15 KNOTS. EXPECT THE WINDS TO BECOME LIGHT TO
CALM IN THE EARLY EVENING AND REMAIN LIGHT THROUGH TUESDAY.
OUTLOOK...
TUE...MAINLY VFR. CHC -TSRA/-SHRA MAINLY DURING THE AFTN INTO THE
EVNG. MVFR-IFR FOG LATE AT NIGHT INTO EARLY IN THE MORNING.
WED...MAINLY VFR. SLIGHT CHC -TSRA/-SHRA.
THU-FRI...VFR/MVFR. CHC -TSRAS/-SHRAS.
&&
.FIRE WEATHER...
VERY WARM AND HUMID CONDITIONS WILL CONTINUE EARLY THIS WEEK WITH
THE THREAT OF SHOWERS AND THUNDERSTORMS MAINLY DURING THE AFTERNOON
AND EVENING HOURS. STORMS WILL HAVE THE POTENTIAL TO PRODUCE LOCALLY
HEAVY RAINFALL. OUR NIGHTS WILL BE CONTINUE TO BE MUGGY WITH PATCHY
FOG. MORE PERSISTENT CHANCES FOR SHOWERS AND THUNDERSTORMS ARE
EXPECTED LATER IN THE WEEK INTO THE WEEKEND AS A SLOW MOVING LOW
PRESSURE SYSTEM IMPACTS THE REGION.
&&
.HYDROLOGY...
INCREASING UNSETTLED WEATHER THIS WEEK. EARLY IN THE WEEK THE CHANCES
OF SHOWERS AND THUNDERSTORMS WILL BE MAINLY DURING THE AFTERNOON AND
EVENING HOURS. HOWEVER...PERSISTENT CHANCES OF SHOWERS AND
THUNDERSTORMS ARE EXPECTED FOR THE LATER PART OF THE WEEK INTO THE
WEEKEND AS A MID/UPPER LEVEL TROUGH IMPACTS THE REGION.
STORMS WILL HAVE THE POTENTIAL TO PRODUCE LOCALLY HEAVY RAINFALL ALL
WEEK WITH HIGH PRECIPITABLE WATER VALUES. EARLY IN THE WEEK FLOW ALOFT
WILL BE RATHER LIGHT SO STORMS WILL BE SLOWER MOVERS. FLOW IS
EXPECTED TO INCREASE LATER IN THE WEEK. PONDING OF WATER ON
ROADWAYS ALONG WITH MINOR FLOODING OF LOW LYING AND POOR DRAINAGE
AREAS WILL BE POSSIBLE. PLUS SOME SMALL STREAMS...CREEKS...AND
BROOKS MAY REACH BANKFULL OR EVEN FLOODING QUICKLY IN THE HEAVY
RAINFALL ASSOCIATED WITH THE THUNDERSTORMS ESPECIALLY IF STORMS
MOVE OVER THE SAME AREA REPEATEDLY.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...IAA
NEAR TERM...IAA/SND/BGM
SHORT TERM...IAA
LONG TERM...WASULA
AVIATION...SND
FIRE WEATHER...IAA
HYDROLOGY...IAA
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
339 PM EDT MON JUN 24 2013
.SHORT TERM /TONIGHT THROUGH TUESDAY/...
500MB SURFACE ANALYSIS SHOWS A TROUGH SITUATED ACROSS NORTHERN
GA...CENTRAL AL AND SOUTHEAST MS. SHOWERS AND THUNDERSTORMS HAVE
DEVELOPED IN THE BASE OF THE TROUGH THIS AFTERNOON...AND CONTINUE TO
APPROACH WESTERN GA. THE LATEST RUN OF THE HRRR HAS THE ACTIVITY
FROM THE WEST CONGEALING WITH THE SE ACTIVITY LATE THIS AFTERNOON.
ACTIVITY SHOULD DECREASE IN STRENGTH AND COVERAGE WITH THE LOSS OF
HEATING FOR THE EARLY EVENING HOURS.
FOR OVERNIGHT...WV LOOP SHOWS A GOOD PIECE OF SHORTWAVE ENERGY
DROPPING SE IN THE FLOW ACROSS W KY THIS AFTERNOON. MODELS DO
DEVELOP SCT ACTIVITY MAINLY ACROSS NORTHERN GA OVERNIGHT. WITH SOME
MARGINAL INSTABILITY PRESENT OVERNIGHT...SCT SHRA/TSRA SEEM VERY
REASONABLE.
THE 500MB TROUGH AXIS IS PROGGED TO BE ACROSS THE CENTRAL CWFA
DURING THE DAY TOMORROW. THIS SHOULD LEAD TO A LITTLE MORE COVERAGE
OF STORMS ACROSS THE REGION. PWATS REMAIN THE SAME ACROSS NORTHERN
GA...BUT WILL CREEP UP TO AROUND 2 INCHES ACROSS THE CENTRAL AND
SOUTHERN CWFA. IN ADDITION...BL WINDS REMAIN VERY LIGHT (AOB
15K)...SO MOVEMENT OF STORMS WILL BE VERY SLOW OR NEARLY STATIONARY.
EVEN THOUGH THE ATMOS WILL BE MARGINALLY UNSTABLE AT THE
SURFACE...MID LEVEL LAPSE RATES AND SHEAR REMAIN VERY WEAK. THE
POTENTIAL FOR SEVERE WEATHER REMAINS LOW...BUT STRONG THUNDERSTORMS
ARE POSSIBLE...WITH AN ISOLATED SEVERE STORM NOT OUT OF THE
QUESTION.
NLISTEMAA
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
DIURNAL CONVECTION EXPECTED TO CONTINUE ACROSS THE AREA EACH
AFTERNOON AND EVENING THROUGH DAY 7. MODELS IN GOOD AGREEMENT
WITH SURFACE RIDGE LOSING ITS GRIP ON THE SOUTHEAST BY WEEKS
END. THEY ARE ALSO IN GOOD AGREEMENT WITH THE UPPER LEVEL RIDGE
BUILDING AND REMAINING OVER THE WESTERN US AS LONG WAVE TROUGH
SETS UP OVER THE EAST COAST BY FRIDAY. WITH THE EASTERN EXTENT OF
THE UPPER LEVEL RIDGE MORE LIMITED THAN PREVIOUSLY EXPECTED...HAVE
COOLED EXTENDED HIGH TEMPERATURES A DEGREE OR TWO. STILL LOOKING
FOR HIGHS IN THE UPPER 80S AND LOW 90S. HAVE INCREASED POPS
SOMEWHAT FOR THE WEEKEND...AND EXPECT THIS UPWARD TREND IN THE
FORECAST TO CONTINUE IN THE COMING DAYS. ENHANCED MOISTURE ACROSS
THE REGION AS A RESULT OF THE UPPER LEVEL TROUGH AND ASSOCIATED
FRONTAL BOUNDARY SHOULD SUPPORT MORE SIGNIFICANT COVERAGE OF
PRECIP ACTIVITY. ANTICIPATE FRONTAL PASSAGE BY EARLY NEXT
WEEK...WITH DROP IN POPS AND SLIGHTLY COOLER TEMPERATURES IN STORE
AS A RESULT.
31/01
&&
.AVIATION...
18Z UPDATE...
NO MAJOR CHANGES TO THE TAFS FOR THIS CYCLE. DIFFERENTIAL HEATING
BOUNDARY AND SHEAR AXIS ALOFT CONTINUE TO DEVELOP SCT SHRA/TSRA
ACROSS NORTHERN GA THIS AFTERNOON. IN ADDITION...A CONVERGENCE
ZONE HAS ALSO DEVELOPED ACROSS THE SE. HAVE GONE VERY CLOSE TO THE
13Z HRRR SOLUTION...WITH THE BEST CHANCE OF TSRA AT ATL BETWEEN 21Z
AND 23Z. COVERAGE SHOULD BE HIGHER TOMORROW AS SHEAR AXIX SLIPS
EAST OVER THE CWFA TOMROROW.
//ATL CONFIDENCE...18Z UPDATE...
MEDIUM CONFIDENCE CONVECTIVE TIMING. HIGH CONFIDENCE REMAINING
ELEMENTS.
NLISTEMAA
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 69 87 69 90 / 50 50 20 30
ATLANTA 70 86 71 88 / 50 50 20 30
BLAIRSVILLE 64 81 64 86 / 40 40 20 40
CARTERSVILLE 69 88 69 89 / 50 40 20 30
COLUMBUS 71 91 72 92 / 60 60 20 30
GAINESVILLE 68 85 70 87 / 50 40 20 30
MACON 71 89 71 90 / 60 60 20 30
ROME 68 89 69 91 / 40 40 20 30
PEACHTREE CITY 69 87 69 88 / 50 50 20 30
VIDALIA 72 88 73 92 / 60 60 20 30
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...NLISTEMAA
LONG TERM....01
AVIATION...NLISTEMAA
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
144 PM EDT MON JUN 24 2013
.PREV DISCUSSION... /ISSUED 1052 AM EDT MON JUN 24 2013/
UPDATE...
500MB ANALYSIS SHOWS A TROUGH ACROSS WESTERN AL. THIS FEATURE HAS
SERVED TO FOCUS MOSTLY SHOWERS THIS MORNING ACROSS NORTH CENTRAL
AL...AND NOW NW GA. DO THINK ANY SCT PRECIP LATE THIS MORNING AND
EARLY AFTERNOON WILL BE CONCENTRATED CLOSEST TO THE TROUGH.
HOWEVER...FOR THE REMAINDER OF THE AFTERNOON...DO THINK PRECIP
WILL FOCUS JUST ALONG AND AHEAD OF THE SEA BREEZE ACROSS THE SE
CWFA. THE 12Z RUN OF THE HRRR SHOWS THIS FAIRLY WELL.
12Z SOUNDING ANALYSIS SHOWS A MOIST COLUMN UP THROUGH 750MB WITH
LIGHT SW FLOW IN THE BOUNDARY LAYER. PWATS ARE AROUND AN INCH AND
THREE QUARTERS...SO ANY THUNDERSTORMS THAT DEVELOP WILL BE CAPABLE
OF PRODUCING LOCALLY HEAVY DOWNPOURS. SURFACE WILL REMAIN PRETTY
UNSTABLE THROUGH THE DAY...SO SCT/NRMS TSTMS WILL BE POSSIBLE. A
FEW THUNDERSTORMS COULD BECOME STRONG AND PRODUCE PROLIFIC
LIGHTNING STRIKES...BUT THE POTENTIAL FOR SEVERE WEATHER IS RATHER
LOW.
PREV DISCUSSION... /ISSUED 734 AM EDT MON JUN 24 2013/
SHORT TERM /TODAY THROUGH TUESDAY/...
/ISSUED AT 402 AM EDT MON JUN 24 2013/
CURRENT CONVECTION OVER THE NORTHEAST MOUNTAINS RESPONDING TO A
MOIST UPSLOPE FLOW ALOFT. THIS WILL SLOWLY SHIFT INTO NORTH CAROLINA
HOWEVER THERE REMAINS ENOUGH OF A RISK TO KEEP LOW POPS GOING INTO
THE MID MORNING HOURS. ISOLATED SHOWERS HAVE ALSO DEVELOPED ACROSS
PARTS OF SOUTH AND EAST GA RESPONDING TO A WEAK SHORT WAVE IN THE
MID LEVELS. THIS KEEPS ENOUGH OF A RISK TO KEEP LOW POPS GOING INTO
THE MID MORNING HOURS AS WELL OVER PARTS OF CENTRAL GA. A SHORT WAVE
MOVING THROUGH THE MISSISSIPPI VALLEY WILL MOVE INTO THE CWA THIS
AFTERNOON. COMBINING THIS WITH AMPLE GULF AND ATLANTIC MOISTURE
SHOULD AID IN SCATTERED TO NUMEROUS THUNDERSTORMS THIS
AFTERNOON...MOST NUMEROUS ACROSS CENTRAL GA WHERE LIKELY POPS SEEM
IN ORDER. CONVECTION SHOULD DIMINISH AFTER SUNSET WITH SOME
LINGERING SHOWERS ACROSS THE NORTHEAST MOUNTAINS AND ALSO CENTRAL GA
INTO THE MORNING HOURS ON TUESDAY.
RISING H5 HEIGHTS WILL INCREASE THICKNESSES TODAY. THIS SHOULD
PRODUCE WARMER TEMPS TODAY. THE NAM IS A BIT COOLER AND HAVE OPTED
FOR THE WARMER GFS BOTH TODAY AND TUESDAY.
17
LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
/ISSUED AT 402 AM EDT MON JUN 24 2013/
DIURNAL CONVECTION EXPECTED EACH AFTERNOON AND EVENING THROUGH THE
WEEK. MODELS IN GOOD AGREEMENT WITH SURFACE RIDGE LOSING ITS GRIP
ON THE SOUTHEAST BY WEEKS END...AND UPPER LEVEL RIDGE BUILDING AND
REMAINING OVER THE WESTERN US AS LONG WAVE TROUGH SETS UP OVER THE
EAST COAST BY FRIDAY. WITH THE EASTERN EXTENT OF THE UPPER LEVEL
RIDGE MORE LIMITED THAN PREVIOUSLY EXPECTED...HAVE COOLED EXTENDED
HIGH TEMPERATURES A DEGREE OR TWO. STILL LOOKING FOR HIGHS IN THE
UPPER 80S AND LOW 90S.
HAVE INCREASED POPS SOMEWHAT FOR THE WEEKEND...AND EXPECT THIS
UPWARD TREND IN THE FORECAST TO CONTINUE IN THE COMING DAYS. ENHANCED
MOISTURE ACROSS THE REGION AS A RESULT OF THE UPPER LEVEL TROUGH
AND ASSOCIATED FRONTAL BOUNDARY SHOULD SUPPORT MORE SIGNIFICANT
COVERAGE OF PRECIP ACTIVITY. ANTICIPATE FRONTAL PASSAGE BY EARLY NEXT
WEEK...WITH DROP IN POPS AND SLIGHTLY COOLER TEMPERATURES IN STORE
AS A RESULT.
31
&&
.AVIATION...
18Z UPDATE...
NO MAJOR CHANGES TO THE TAFS FOR THIS CYCLE. DIFFERENTIAL HEATING
BOUNDARY AND SHEAR AXIS ALOFT CONTINUE TO DEVELOP SCT SHRA/TSRA
ACROSS NORTHERN GA THIS AFTERNOON. IN ADDITION...A CONVERGENCE
ZONE HAS ALSO DEVELOPED ACROSS THE SE. HAVE GONE VERY CLOSE TO THE
13Z HRRR SOLUTION...WITH THE BEST CHANCE OF TSRA AT ATL BETWEEN 21Z
AND 23Z. COVERAGE SHOULD BE HIGHER TOMORROW AS SHEAR AXIX SLIPS
EAST OVER THE CWFA TOMROROW.
//ATL CONFIDENCE...18Z UPDATE...
MEDIUM CONFIDENCE CONVECTIVE TIMING. HIGH CONFIDENCE REMAINING
ELEMENTS.
NLISTEMAA
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 87 69 89 70 / 50 50 50 20
ATLANTA 88 71 88 72 / 50 50 50 20
BLAIRSVILLE 83 63 84 65 / 40 40 40 20
CARTERSVILLE 87 68 88 70 / 50 50 40 20
COLUMBUS 91 73 92 73 / 50 50 60 20
GAINESVILLE 86 69 88 71 / 50 50 40 20
MACON 89 70 91 72 / 60 60 60 20
ROME 89 68 91 70 / 40 40 40 20
PEACHTREE CITY 88 68 90 70 / 50 50 50 20
VIDALIA 91 73 91 74 / 60 60 60 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
516 PM CDT MON JUN 24 2013
.MESOSCALE DISCUSSION...
505 PM CDT
THE MOST FOCUS REMAINS ALONG THE I-88 CORRIDOR AND NORTH AND SOUTH
OF THAT BY AROUND 30 MILES. THE APEX IS MOVING AT A FORWARD SPEED
OF 60+ MPH AND THE MESO-VORTICY NEAR THE DEKALB/LASALLE BORDER HAS
A FAIRLY LONG HISTORY...AFTER WEAKENING SOME FROM BUREAU COUNTY
AND NOW HAS RE-INTENSIFIED. THIS CONTINUES TO BE VERY CLOSE TO A
WEST-TO-EAST BOUNDARY PER EARLIER VISIBLE SATELLITE. 0-3 KM CAPE
FROM SPC RAP OBJECTIVE ANALYSIS HAS VALUES AT 150-175 J/KG...SO
CERTAINLY FAVORABLE FOR STRETCHING ALONG THIS. STILL...THE PRIMARY
WIDESPREAD THREAT REMAINS DAMAGING WINDS PER RADAR AND
ENVIRONMENTAL SIGNATURES.
ON THE LARGE SCALE RADAR AND SATELLITE THIS FORWARD-PROPAGATING MCS
LOOKS VERY WELL-ORGANIZED. THE ENVIRONMENT CONTINUES TO BE
FAVORABLE FOR SUSTAINABILITY...WITH DEEP CAPE AT OR IN EXCESS OF
3000 J/KG...STEEP LOW-LEVEL LAPSE RATES AND ASSOCIATED THETA-E
DIFFERENCE...AND STRONG 0-1 AND 0-3 KM SHEAR ADVECTING EAST WITHIN
THE MCS FOR COLD POOL SUSTAINABILITY.
MTF
.DISCUSSION...
327 PM CDT
SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT...
A VERY ACTIVE PERIOD OF WEATHER IS EXPECTED...AT LEAST FOR PORTIONS
OF THE AREA...THROUGH WEDNESDAY. THIS INCLUDES A FEW PERIODS OF
SEVERE THUNDERSTORMS AND ALSO A GOOD THREAT FOR VERY HEAVY RAINFALL
AND POSSIBLE FLASH FLOODING. AS SUCH...THIS WILL BE THE FOCUS OF THE
FORECAST.
WE HAVE EXTENDED THE FLASH FLOOD WATCH FOR OUR WESTERN COUNTIES
THROUGH TONIGHT.
TEMPERATURES ACROSS NORTHERN ILLINOIS AND NW INDIANA HAVE JUMPED
INTO THE LOW TO MID 80S OVER THE PAST COUPLE HOURS AFTER THE MORNING
CLOUD COVER CLEARED. WITH DEW POINTS NEAR 70...THIS IS RESULTING IN
MLCAPES AROUND 2,000 J/KG ACROSS THE AREA...PER SPC MESOANALYSIS
PAGE. IN ADDITION...IT APPEARS THAT THE 0-6 KM SHEAR MAY END UP A
BIT STRONGER THAN PREVIOUSLY THOUGHT. VWP DATA INDICATES THAT A SPEED
MAX AROUND 50 KT ...ASSOCIATED WITH A MID LEVEL DISTURBANCE MOVING
INTO NORTHWESTERN IOWA...IS PUNCHING EASTWARD ACROSS IOWA. THUS IT
APPEARS THAT 40 KT OF DEEP LAYER SHEER MAY OVERSPREAD THIS AREA
LATER THIS AFTERNOON AND EVENING AS THIS SPEED MAX SHIFTS EASTWARD.
CURRENT THOUGHTS ARE THAT THE LINE OF CONVECTION TO THE WEST WILL
POSE A SEVERE THREAT FOR MOST OF THE AREA INTO THE EARLY EVENING
HOURS. STRONG DAMAGING WINDS...POSSIBLY IN EXCESS OF 80 MPH...WILL
BE THE PRIMARY THREAT ALONG WITH A SMALL POTENTIAL OF SOME
MARGINALLY SEVERE HAIL.
IT APPEARS THE MAIN FOCUS FOR CONVECTION MAY SHIFT NORTH INTO
WISCONSIN LATER TONIGHT AS THE LOW LEVEL JET FOCUSES FARTHER NORTH.
HOWEVER...THIS APPEARS TO BE SHORTED LIVED...AS CONVECTIVE CHANCES
WILL RETURN ON TUESDAY. IT APPEARS THAT ADDITIONAL PERTURBATIONS IN
THE MEAN QUASI-ZONAL MID LEVEL FLOW...WILL INTERACT WITH THE VERY
MOIST AND UNSTABLE ATMOSPHERE ACROSS THE AREA. IT APPEARS THE CAP
WILL REMAIN FAIRLY WEAK DURING THE DAY...SO IT APPEARS THAT AT LEAST
SOME WIDELY SCATTERED CONVECTION MAY OCCUR...MAINLY ACROSS FAR
NORTHERN ILLINOIS. THIS ACTIVITY COULD AGAIN POSS A SEVERE RISK
ACROSS NORTHERN ILLINOIS WITH STEEP MID LEVEL LAPSE RATES HELPING
PRODUCE MLCAPES IN EXCESS OF 3000 J/KG.
TUESDAY CONVECTION LOOKS LIKE IT WILL BECOME MORE NUMEROUS TUESDAY
EVENING/NIGHT. THE QUASI-ZONAL FLOW PATTERN ACROSS THE CONUS IS
EXPECTED TO BEGIN AMPLIFYING...IN RESPONSE TO AN UPPER LOW OVER THE
EASTERN PACIFIC. ULTIMATELY THIS WILL SET THE STAGE FROM A BUILDING
MID/UPPER LEVEL RIDGE ACROSS THE WESTERN CONUS AND FALLING HEIGHTS
ACROSS THE GREAT LAKES REGION. THIS PROCESS SHOULD ALLOW
ANOTHER...STRONGER...SHORT WAVE TO MOVE ACROSS THE AREA ON
WEDNESDAY. IT APPEARS THIS FEATURE WILL FOCUS THE NOSE OF A 40 KT
LOW LEVEL JET RIGHT ACROSS SOUTHERN WISCONSIN AND NORTHERN ILLINOIS
TUESDAY NIGHT INTO WEDNESDAY. THIS COULD SET THE STAGE FOR VERY HEAVY
RAINFALL ACROSS PORTIONS OF NORTHERN ILLINOIS INTO WEDNESDAY. THIS
LOOKS TO BE THE PERIOD TO REALLY WATCH FOR POSSIBLE FLOODING ACROSS
THE AREA. PWATS ARE PROGGED TO REACH NEARLY 2.00 INCHES...WHICH IS
AROUND THE 99 PERCENTILE. IN ADDITION...THE SOUTHWESTERLY ORIENTATION
OF THE LOW LEVEL JET COULD OFFSET THE MEAN CLOUD BEARING
FLOW...POSSIBLY RESULTING IN SLOW MOVING OR BACK BUILDING SEGMENTS
TUESDAY NIGHT. HOWEVER...CONFIDENCE IN THE EXACT PLACEMENT OF THE
HEAVIEST RAIN REMAINS IN QUESTION AT THIS TIME...BUT GUIDANCE IS
HINTING THAT NORTHERN ILLINOIS COULD LIE IN THE FAVORED ZONE. THIS
WILL HAVE TO BE WATCHED...WITH THE POSSIBLY OF A FLASH FLOOD WATCH
NEEDED FOR PORTIONS OF NORTHERN ILLINOIS AND NORTHWESTERN INDIANA
DURING THIS PERIOD.
THE SEVERE CONVECTIVE THREAT SHOULD BEGIN TO WANE WEDNESDAY
EVENING AS THE MID LEVEL DISTURBANCE SHIFT EAST OF THE AREA.
TEMPERATURES LOOK TO CONTINUE TO BE PROBLEMATIC FOR THE NEXT COUPLE
OF DAYS...WITH ADDITIONAL BUST POTENTIAL WITH CONVECTIVE ACTIVITY.
HOWEVER...I ONLY MADE MINOR CHANCES TO THE GOING TEMP
FORECAST...MAINLY TO COOL THE NORTHERN AREAS BY A COUPLE DEGREES.
KJB
EXTENDED FORECAST...THURSDAY THROUGH MONDAY...
QUASI ZONAL FLOW IN THE SOUTHERN STREAM EARLY IN THE WEEK WILL
TRANSITION BY THE SECOND HALF OF THE WEEK TO AN INCREASINGLY
AMPLIFIED BROAD WESTERN CONUS RIDGE AND ITS CORRESPONDING LONGWAVE
TROUGH OVER THE EASTERN CONUS. THIS WOULD PUT THE LOCAL AREA IN
NORTHWEST UPPER FLOW EARLY IN THE WEEKEND...AND THEN UNDER AN UPPER
LOW PUSHING SOUTHWEST ACROSS THE GREAT LAKES BY SUNDAY. THE MOST
OBVIOUS RAMIFICATION WILL BE MUCH COOLER HIGHS...ESPECIALLY FOR THE
WEEKEND AND EARLY NEXT WEEK. IN ADDITION...GFS/ECMWF ARE SUGGESTING
THE POSSIBILITY OF THUNDERSTORMS TRIGGERED BY SHORTWAVE ENERGY
DROPPING ACROSS THE AREA INTO THE BASE OF THE EASTERN TROUGH
THURSDAY AND FRIDAY...WHEN CONSIDERABLE LOW LEVEL MOISTURE REMAINS
IN PLACE OVER THE AREA. DEWPOINTS FALL ALONG WITH THE TEMPERATURES
BY THE WEEKEND...BUT THE DEEPENING UPPER LOW ALSO SUPPORTS A
CONTINUED CHANCE OF SHOWERS INTO MONDAY.
EML
&&
.DISCUSSION...
327 PM CDT
SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT...
A VERY ACTIVE PERIOD OF WEATHER IS EXPECTED...AT LEAST FOR PORTIONS
OF THE AREA...THROUGH WEDNESDAY. THIS INCLUDES A FEW PERIODS OF
SEVERE THUNDERSTORMS AND ALSO A GOOD THREAT FOR VERY HEAVY RAINFALL
AND POSSIBLE FLASH FLOODING. AS SUCH...THIS WILL BE THE FOCUS OF THE
FORECAST.
WE HAVE EXTENDED THE FLASH FLOOD WATCH FOR OUR WESTERN COUNTIES
THROUGH TONIGHT.
TEMPERATURES ACROSS NORTHERN ILLINOIS AND NW INDIANA HAVE JUMPED
INTO THE LOW TO MID 80S OVER THE PAST COUPLE HOURS AFTER THE MORNING
CLOUD COVER CLEARED. WITH DEW POINTS NEAR 70...THIS IS RESULTING IN
MLCAPES AROUND 2,000 J/KG ACROSS THE AREA...PER SPC MESOANALYSIS
PAGE. IN ADDITION...IT APPEARS THAT THE 0-6 KM SHEAR MAY END UP A
BIT STRONGER THAN PREVIOUSLY THOUGHT. VWP DATA INDICATES THAT A SPEED
MAX AROUND 50 KT ...ASSOCIATED WITH A MID LEVEL DISTURBANCE MOVING
INTO NORTHWESTERN IOWA...IS PUNCHING EASTWARD ACROSS IOWA. THUS IT
APPEARS THAT 40 KT OF DEEP LAYER SHEER MAY OVERSPREAD THIS AREA
LATER THIS AFTERNOON AND EVENING AS THIS SPEED MAX SHIFTS EASTWARD.
CURRENT THOUGHTS ARE THAT THE LINE OF CONVECTION TO THE WEST WILL
POSE A SEVERE THREAT FOR MOST OF THE AREA INTO THE EARLY EVENING
HOURS. STRONG DAMAGING WINDS...POSSIBLY IN EXCESS OF 80 MPH...WILL
BE THE PRIMARY THREAT ALONG WITH A SMALL POTENTIAL OF SOME
MARGINALLY SEVERE HAIL.
IT APPEARS THE MAIN FOCUS FOR CONVECTION MAY SHIFT NORTH INTO
WISCONSIN LATER TONIGHT AS THE LOW LEVEL JET FOCUSES FARTHER NORTH.
HOWEVER...THIS APPEARS TO BE SHORTED LIVED...AS CONVECTIVE CHANCES
WILL RETURN ON TUESDAY. IT APPEARS THAT ADDITIONAL PERTURBATIONS IN
THE MEAN QUASI-ZONAL MID LEVEL FLOW...WILL INTERACT WITH THE VERY
MOIST AND UNSTABLE ATMOSPHERE ACROSS THE AREA. IT APPEARS THE CAP
WILL REMAIN FAIRLY WEAK DURING THE DAY...SO IT APPEARS THAT AT LEAST
SOME WIDELY SCATTERED CONVECTION MAY OCCUR...MAINLY ACROSS FAR
NORTHERN ILLINOIS. THIS ACTIVITY COULD AGAIN POSS A SEVERE RISK
ACROSS NORTHERN ILLINOIS WITH STEEP MID LEVEL LAPSE RATES HELPING
PRODUCE MLCAPES IN EXCESS OF 3000 J/KG.
TUESDAY CONVECTION LOOKS LIKE IT WILL BECOME MORE NUMEROUS TUESDAY
EVENING/NIGHT. THE QUASI-ZONAL FLOW PATTERN ACROSS THE CONUS IS
EXPECTED TO BEGIN AMPLIFYING...IN RESPONSE TO AN UPPER LOW OVER THE
EASTERN PACIFIC. ULTIMATELY THIS WILL SET THE STAGE FROM A BUILDING
MID/UPPER LEVEL RIDGE ACROSS THE WESTERN CONUS AND FALLING HEIGHTS
ACROSS THE GREAT LAKES REGION. THIS PROCESS SHOULD ALLOW
ANOTHER...STRONGER...SHORT WAVE TO MOVE ACROSS THE AREA ON
WEDNESDAY. IT APPEARS THIS FEATURE WILL FOCUS THE NOSE OF A 40 KT
LOW LEVEL JET RIGHT ACROSS SOUTHERN WISCONSIN AND NORTHERN ILLINOIS
TUESDAY NIGHT INTO WEDNESDAY. THIS COULD SET THE STAGE FOR VERY HEAVY
RAINFALL ACROSS PORTIONS OF NORTHERN ILLINOIS INTO WEDNESDAY. THIS
LOOKS TO BE THE PERIOD TO REALLY WATCH FOR POSSIBLE FLOODING ACROSS
THE AREA. PWATS ARE PROGGED TO REACH NEARLY 2.00 INCHES...WHICH IS
AROUND THE 99 PERCENTILE. IN ADDITION...THE SOUTHWESTERLY ORIENTATION
OF THE LOW LEVEL JET COULD OFFSET THE MEAN CLOUD BEARING
FLOW...POSSIBLY RESULTING IN SLOW MOVING OR BACK BUILDING SEGMENTS
TUESDAY NIGHT. HOWEVER...CONFIDENCE IN THE EXACT PLACEMENT OF THE
HEAVIEST RAIN REMAINS IN QUESTION AT THIS TIME...BUT GUIDANCE IS
HINTING THAT NORTHERN ILLINOIS COULD LIE IN THE FAVORED ZONE. THIS
WILL HAVE TO BE WATCHED...WITH THE POSSIBLY OF A FLASH FLOOD WATCH
NEEDED FOR PORTIONS OF NORTHERN ILLINOIS AND NORTHWESTERN INDIANA
DURING THIS PERIOD.
THE SEVERE CONVECTIVE THREAT SHOULD BEGIN TO WANE WEDNESDAY
EVENING AS THE MID LEVEL DISTURBANCE SHIFT EAST OF THE AREA.
TEMPERATURES LOOK TO CONTINUE TO BE PROBLEMATIC FOR THE NEXT COUPLE
OF DAYS...WITH ADDITIONAL BUST POTENTIAL WITH CONVECTIVE ACTIVITY.
HOWEVER...I ONLY MADE MINOR CHANCES TO THE GOING TEMP
FORECAST...MAINLY TO COOL THE NORTHERN AREAS BY A COUPLE DEGREES.
KJB
EXTENDED FORECAST...THURSDAY THROUGH MONDAY...
QUASI ZONAL FLOW IN THE SOUTHERN STREAM EARLY IN THE WEEK WILL
TRANSITION BY THE SECOND HALF OF THE WEEK TO AN INCREASINGLY
AMPLIFIED BROAD WESTERN CONUS RIDGE AND ITS CORRESPONDING LONGWAVE
TROUGH OVER THE EASTERN CONUS. THIS WOULD PUT THE LOCAL AREA IN
NORTHWEST UPPER FLOW EARLY IN THE WEEKEND...AND THEN UNDER AN UPPER
LOW PUSHING SOUTHWEST ACROSS THE GREAT LAKES BY SUNDAY. THE MOST
OBVIOUS RAMIFICATION WILL BE MUCH COOLER HIGHS...ESPECIALLY FOR THE
WEEKEND AND EARLY NEXT WEEK. IN ADDITION...GFS/ECMWF ARE SUGGESTING
THE POSSIBILITY OF THUNDERSTORMS TRIGGERED BY SHORTWAVE ENERGY
DROPPING ACROSS THE AREA INTO THE BASE OF THE EASTERN TROUGH
THURSDAY AND FRIDAY...WHEN CONSIDERABLE LOW LEVEL MOISTURE REMAINS
IN PLACE OVER THE AREA. DEWPOINTS FALL ALONG WITH THE TEMPERATURES
BY THE WEEKEND...BUT THE DEEPENING UPPER LOW ALSO SUPPORTS A
CONTINUED CHANCE OF SHOWERS INTO MONDAY.
EML
&&
.HYDROLOGY...
433 PM CDT
A SHORT PERIOD OF HEAVY RAINFALL WILL ACCOMPANY THE LINE OF STORMS
CURRENTLY APPROACHING NORTH CENTRAL ILLINOIS. THIS COULD RESULT IN
SOME MINOR FLOODING...ESPECIALLY IN AREAS THAT WERE HIT WITH 1 TO 2
INCHES OF RAINFALL THIS MORNING. HOWEVER...ADDITIONAL PERIODS OF
HEAVY RAINFALL ARE EXPECTED LATE TUESDAY INTO WEDNESDAY. DURING THIS
PERIOD PRECIPITABLE WATER VALUES COULD BE AROUND 2 INCHES...WHICH
IS AROUND THE 99TH PERCENTILE. ANOTHER DECENT MID LEVEL DISTURBANCE
IS EXPECTED TO APPROACH THE AREA TUESDAY NIGHT AND INTO
WEDNESDAY...AND THIS SYSTEM LOOKS TO INDUCE A SOUTHWESTERLY LOW
LEVEL JET...THAT COULD OFFSET THE FORWARD STORM MOTION...RESULTING
IN SLOW MOVING OR BACK BUILDING THUNDERSTORMS TUESDAY NIGHT INTO
WEDNESDAY. AT THIS TIME...UNCERTAINTY REMAINS AS TO WHERE EXACTLY
THE HEAVIEST RAIN WILL FALL...BUT GUIDANCE CONTINUES TO HINT AT
NORTHERN ILLINOIS AND NORTHWESTERN INDIANA. THIS WILL HAVE TO BE
WATCHED FOR POSSIBILITY OF A FLASH FLOOD WATCH FOR MOST OF THE
AREA AS RAINFALL AMOUNTS IN EXCESS OF 2 INCHES IS CERTAINLY
POSSIBLE ACROSS PORTIONS OF THE AREA.
KJB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* SQUALL LINE/BOW ECHO TO IMPACT ORD/MDW AT 23Z
* POTENTIAL FOR DAMAGING WIND GUSTS OF 60-75 KTS
* VSBY REDUCED LESS THAN 1 MILE IN TORRENTIAL RAIN LASTING 15-25 MIN
* STRONGEST WINDS LASTING 5 TO 10 MIN
* PSBL FOG DEVELOPMENT OVERNIGHT INTO EARLY TUE.
ED F
//DISCUSSION...UPDATED 18Z...
WARM AND HUMID CONDITIONS IN PLACE ALONG WITH VARIOUS BOUNDARIES TO
KEEP NEXT ROUND OF SHRA/TSRA IN THE FORECAST INTO THIS EVENING.
ATMOSPHERE TO CONTINUE TO RECOVER FROM MORNING CONVECTIVE ACTIVITY.
THINKING IS A FEW TSRA ARE POSSIBLE BY MID AFTERNOON IN AREAS OF
LESSENING/THINNING OF CLOUD COVER AND MAY EXPAND IN COVERAGE BY LATE
AFTERNOON IF MORE WIDESPREAD SUNSHINE OCCURS. CIRROSTRATUS SHIELD
ASSOCIATED WITH ORGANIZED AREAS OF TSRA/SHRA OVER IA MAY LIMIT
AMOUNT/DURATION OF SUN. TSRA CLUSTERS OVER IA EXPECTED TO ORGANIZE
FURTHER AND TRACK ACROSS NORTHERN ILLINOIS AND POSSIBLY NORTHWEST
INDIANA INTO THE EVENING.
SURFACE WARM FRONT EXPECTED TO REMAIN IN THE VICINITY OR JUST SOUTH
OF THE TERMINALS. GIVEN HUMID ATMOSPHERE AND ADDITIONAL RAINFALL
AREAS OF MAINLY LIGHT FOG ARE LIKELY OVERNIGHT.
ZEBIC
//ORD AND MDW CONFIDENCE...UPDATED 22Z...
* HIGH CONFIDENCE IN SHRA/TSRA...MEDIUM CONFIDENCE IN PRECISE
TIMING
* LOW CONFIDENNCE IN SPECIFC PEAK WIND GUST VALUE - BEST ESTIMATE
45-50 KTS BUT POTENTIAL FOR GUST TO 75 KTS EXISTS.
* LOW CONFIDENCE IN WIND FORECAST ONCE SQUALL LINE MOVES THROUGH...
MAY SEE PERIOD OF EAST WINDS.
* LOW CONFIDENCE IN OVERNIGHT FOG DEVELOPMENT REDUCING VSBYS.
ED F
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT THROUGH FRIDAY...PERIODIC CHANCES FOR
THUNDERSTORMS. OTHERWISE EXPECT VFR CIGS.
FRIDAY AND SATURDAY...CHANCE FOR SHOWERS. MAINLY VFR.
SUNDAY...VFR.
BEACHLER
&&
.MARINE...
411 PM CDT
HIGH PRESSURE REMAINS PARKED OFF THE CAROLINA COASTWHILE LOW
PRESSURE CONTINUES TO DRIFT NORTHWARD ACROSS CENTRAL MANITOBA AND
ONTARIO. ADDITIONAL LOW PRESSURE WILL DEVELOP FROM THE CANADIAN
PRAIRIES TO THE NORTHERN PLAINS TUESDAY AND MOVE EASTWARD INTO
WEDNESDAY WITH A CLOSED LOW DEVELOPING OVER THE WESTERN GREAT LAKES
BY WEDNESDAY NIGHT. A LARGER LOW WILL DEVELOP IVER THE GREAT LAKES
LATER FRIDAY AND LIKELY LINGER THROUGH THE WEEKEND BEFORE HIGH
PRESSURE BUILDS IN FROM THE WEST EARLY NEXT WEEK. SOUTHERN WINDS
WILL BE IN PLACE INTO WEDNESDAY WHEN THE FIRST SFC LOW PASSES WHICH
WILL TURN WINDS WEST AND NORTHWEST. SPEEDS WILL FLUCTUATE UP AND
DOWN UNTIL THE LOW PASSES SIMILAR TO PREVIOUS DAYS. A STABLE AIR
MASS OVER THE WATER WILL KEEP AREAS OF DENSE FOG GOING ACROSS MUCH
OF THE NORTHERN PART OF THE LAKE INTO TUESDAY AND PROBABLY INTO
WEDNESDAY FOR THAT MATTER SO THE DENSE FOG ADVISORY MAY NEED TO BE
EXTENDED. WIND SPEEDS LOOK TO REMAIN ON THE LIGHER SIDE FROM
WEDNESDAY THROUGH THE WEEKEND WITH A FAIRLY BAGGY PRESSURE GRADIENT
DEVELOPING AND THE DIRECTION WILL LIKELY VARY FROM WEST TO NORTH.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ008-ILZ010-ILZ011-ILZ019
UNTIL 7 AM TUESDAY.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565
UNTIL 10 AM TUESDAY.
&&
$$
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AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
510 PM CDT MON JUN 24 2013
.MESOSCALE DISCUSSION...
505 PM CDT
THE MOST FOCUS REMAINS ALONG THE I-88 CORRIDOR AND NORTH AND SOUTH
OF THAT BY AROUND 30 MILES. THE APEX IS MOVING AT A FORWARD SPEED
OF 60+ MPH AND THE MESO-VORTICY NEAR THE DEKALB/LASALLE BORDER HAS
A FAIRLY LONG HISTORY...AFTER WEAKENING SOME FROM BUREAU COUNTY
AND NOW HAS RE-INTENSIFIED. THIS CONTINUES TO BE VERY CLOSE TO A
WEST-TO-EAST BOUNDARY PER EARLIER VISIBLE SATELLITE. 0-3 KM CAPE
FROM SPC RAP OBJECTIVE ANALYSIS HAS VALUES AT 150-175 J/KG...SO
CERTAINLY FAVORABLE FOR STRETCHING ALONG THIS. STILL...THE PRIMARY
WIDESPREAD THREAT REMAINS DAMAGING WINDS PER RADAR AND
ENVIRONMENTAL SIGNATURES.
ON THE LARGE SCALE RADAR AND SATELLITE THIS FORWARD-PROPAGATING MCS
LOOKS VERY WELL-ORGANIZED. THE ENVIRONMENT CONTINUES TO BE
FAVORABLE FOR SUSTAINABILITY...WITH DEEP CAPE AT OR IN EXCESS OF
3000 J/KG...STEEP LOW-LEVEL LAPSE RATES AND ASSOCIATED THETA-E
DIFFERENCE...AND STRONG 0-1 AND 0-3 KM SHEAR ADVECTING EAST WITHIN
THE MCS FOR COLD POOL SUSTAINABILITY.
MTF
.DISCUSSION...
327 PM CDT
SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT...
A VERY ACTIVE PERIOD OF WEATHER IS EXPECTED...AT LEAST FOR PORTIONS
OF THE AREA...THROUGH WEDNESDAY. THIS INCLUDES A FEW PERIODS OF
SEVERE THUNDERSTORMS AND ALSO A GOOD THREAT FOR VERY HEAVY RAINFALL
AND POSSIBLE FLASH FLOODING. AS SUCH...THIS WILL BE THE FOCUS OF THE
FORECAST.
WE HAVE EXTENDED THE FLASH FLOOD WATCH FOR OUR WESTERN COUNTIES
THROUGH TONIGHT.
TEMPERATURES ACROSS NORTHERN ILLINOIS AND NW INDIANA HAVE JUMPED
INTO THE LOW TO MID 80S OVER THE PAST COUPLE HOURS AFTER THE MORNING
CLOUD COVER CLEARED. WITH DEW POINTS NEAR 70...THIS IS RESULTING IN
MLCAPES AROUND 2,000 J/KG ACROSS THE AREA...PER SPC MESOANALYSIS
PAGE. IN ADDITION...IT APPEARS THAT THE 0-6 KM SHEAR MAY END UP A
BIT STRONGER THAN PREVIOUSLY THOUGHT. VWP DATA INDICATES THAT A SPEED
MAX AROUND 50 KT ...ASSOCIATED WITH A MID LEVEL DISTURBANCE MOVING
INTO NORTHWESTERN IOWA...IS PUNCHING EASTWARD ACROSS IOWA. THUS IT
APPEARS THAT 40 KT OF DEEP LAYER SHEER MAY OVERSPREAD THIS AREA
LATER THIS AFTERNOON AND EVENING AS THIS SPEED MAX SHIFTS EASTWARD.
CURRENT THOUGHTS ARE THAT THE LINE OF CONVECTION TO THE WEST WILL
POSE A SEVERE THREAT FOR MOST OF THE AREA INTO THE EARLY EVENING
HOURS. STRONG DAMAGING WINDS...POSSIBLY IN EXCESS OF 80 MPH...WILL
BE THE PRIMARY THREAT ALONG WITH A SMALL POTENTIAL OF SOME
MARGINALLY SEVERE HAIL.
IT APPEARS THE MAIN FOCUS FOR CONVECTION MAY SHIFT NORTH INTO
WISCONSIN LATER TONIGHT AS THE LOW LEVEL JET FOCUSES FARTHER NORTH.
HOWEVER...THIS APPEARS TO BE SHORTED LIVED...AS CONVECTIVE CHANCES
WILL RETURN ON TUESDAY. IT APPEARS THAT ADDITIONAL PERTURBATIONS IN
THE MEAN QUASI-ZONAL MID LEVEL FLOW...WILL INTERACT WITH THE VERY
MOIST AND UNSTABLE ATMOSPHERE ACROSS THE AREA. IT APPEARS THE CAP
WILL REMAIN FAIRLY WEAK DURING THE DAY...SO IT APPEARS THAT AT LEAST
SOME WIDELY SCATTERED CONVECTION MAY OCCUR...MAINLY ACROSS FAR
NORTHERN ILLINOIS. THIS ACTIVITY COULD AGAIN POSS A SEVERE RISK
ACROSS NORTHERN ILLINOIS WITH STEEP MID LEVEL LAPSE RATES HELPING
PRODUCE MLCAPES IN EXCESS OF 3000 J/KG.
TUESDAY CONVECTION LOOKS LIKE IT WILL BECOME MORE NUMEROUS TUESDAY
EVENING/NIGHT. THE QUASI-ZONAL FLOW PATTERN ACROSS THE CONUS IS
EXPECTED TO BEGIN AMPLIFYING...IN RESPONSE TO AN UPPER LOW OVER THE
EASTERN PACIFIC. ULTIMATELY THIS WILL SET THE STAGE FROM A BUILDING
MID/UPPER LEVEL RIDGE ACROSS THE WESTERN CONUS AND FALLING HEIGHTS
ACROSS THE GREAT LAKES REGION. THIS PROCESS SHOULD ALLOW
ANOTHER...STRONGER...SHORT WAVE TO MOVE ACROSS THE AREA ON
WEDNESDAY. IT APPEARS THIS FEATURE WILL FOCUS THE NOSE OF A 40 KT
LOW LEVEL JET RIGHT ACROSS SOUTHERN WISCONSIN AND NORTHERN ILLINOIS
TUESDAY NIGHT INTO WEDNESDAY. THIS COULD SET THE STAGE FOR VERY HEAVY
RAINFALL ACROSS PORTIONS OF NORTHERN ILLINOIS INTO WEDNESDAY. THIS
LOOKS TO BE THE PERIOD TO REALLY WATCH FOR POSSIBLE FLOODING ACROSS
THE AREA. PWATS ARE PROGGED TO REACH NEARLY 2.00 INCHES...WHICH IS
AROUND THE 99 PERCENTILE. IN ADDITION...THE SOUTHWESTERLY ORIENTATION
OF THE LOW LEVEL JET COULD OFFSET THE MEAN CLOUD BEARING
FLOW...POSSIBLY RESULTING IN SLOW MOVING OR BACK BUILDING SEGMENTS
TUESDAY NIGHT. HOWEVER...CONFIDENCE IN THE EXACT PLACEMENT OF THE
HEAVIEST RAIN REMAINS IN QUESTION AT THIS TIME...BUT GUIDANCE IS
HINTING THAT NORTHERN ILLINOIS COULD LIE IN THE FAVORED ZONE. THIS
WILL HAVE TO BE WATCHED...WITH THE POSSIBLY OF A FLASH FLOOD WATCH
NEEDED FOR PORTIONS OF NORTHERN ILLINOIS AND NORTHWESTERN INDIANA
DURING THIS PERIOD.
THE SEVERE CONVECTIVE THREAT SHOULD BEGIN TO WANE WEDNESDAY
EVENING AS THE MID LEVEL DISTURBANCE SHIFT EAST OF THE AREA.
TEMPERATURES LOOK TO CONTINUE TO BE PROBLEMATIC FOR THE NEXT COUPLE
OF DAYS...WITH ADDITIONAL BUST POTENTIAL WITH CONVECTIVE ACTIVITY.
HOWEVER...I ONLY MADE MINOR CHANCES TO THE GOING TEMP
FORECAST...MAINLY TO COOL THE NORTHERN AREAS BY A COUPLE DEGREES.
KJB
EXTENDED FORECAST...THURSDAY THROUGH MONDAY...
QUASI ZONAL FLOW IN THE SOUTHERN STREAM EARLY IN THE WEEK WILL
TRANSITION BY THE SECOND HALF OF THE WEEK TO AN INCREASINGLY
AMPLIFIED BROAD WESTERN CONUS RIDGE AND ITS CORRESPONDING LONGWAVE
TROUGH OVER THE EASTERN CONUS. THIS WOULD PUT THE LOCAL AREA IN
NORTHWEST UPPER FLOW EARLY IN THE WEEKEND...AND THEN UNDER AN UPPER
LOW PUSHING SOUTHWEST ACROSS THE GREAT LAKES BY SUNDAY. THE MOST
OBVIOUS RAMIFICATION WILL BE MUCH COOLER HIGHS...ESPECIALLY FOR THE
WEEKEND AND EARLY NEXT WEEK. IN ADDITION...GFS/ECMWF ARE SUGGESTING
THE POSSIBILITY OF THUNDERSTORMS TRIGGERED BY SHORTWAVE ENERGY
DROPPING ACROSS THE AREA INTO THE BASE OF THE EASTERN TROUGH
THURSDAY AND FRIDAY...WHEN CONSIDERABLE LOW LEVEL MOISTURE REMAINS
IN PLACE OVER THE AREA. DEWPOINTS FALL ALONG WITH THE TEMPERATURES
BY THE WEEKEND...BUT THE DEEPENING UPPER LOW ALSO SUPPORTS A
CONTINUED CHANCE OF SHOWERS INTO MONDAY.
EML
&&
.HYDROLOGY...
433 PM CDT
A SHORT PERIOD OF HEAVY RAINFALL WILL ACCOMPANY THE LINE OF STORMS
CURRENTLY APPROACHING NORTH CENTRAL ILLINOIS. THIS COULD RESULT IN
SOME MINOR FLOODING...ESPECIALLY IN AREAS THAT WERE HIT WITH 1 TO 2
INCHES OF RAINFALL THIS MORNING. HOWEVER...ADDITIONAL PERIODS OF
HEAVY RAINFALL ARE EXPECTED LATE TUESDAY INTO WEDNESDAY. DURING THIS
PERIOD PRECIPITABLE WATER VALUES COULD BE AROUND 2 INCHES...WHICH
IS AROUND THE 99TH PERCENTILE. ANOTHER DECENT MID LEVEL DISTURBANCE
IS EXPECTED TO APPROACH THE AREA TUESDAY NIGHT AND INTO
WEDNESDAY...AND THIS SYSTEM LOOKS TO INDUCE A SOUTHWESTERLY LOW
LEVEL JET...THAT COULD OFFSET THE FORWARD STORM MOTION...RESULTING
IN SLOW MOVING OR BACK BUILDING THUNDERSTORMS TUESDAY NIGHT INTO
WEDNESDAY. AT THIS TIME...UNCERTAINTY REMAINS AS TO WHERE EXACTLY
THE HEAVIEST RAIN WILL FALL...BUT GUIDANCE CONTINUES TO HINT AT
NORTHERN ILLINOIS AND NORTHWESTERN INDIANA. THIS WILL HAVE TO BE
WATCHED FOR POSSIBILITY OF A FLASH FLOOD WATCH FOR MOST OF THE
AREA AS RAINFALL AMOUNTS IN EXCESS OF 2 INCHES IS CERTAINLY
POSSIBLE ACROSS PORTIONS OF THE AREA.
KJB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* SHRA/TSRA INTO EVENING AND ASSOCIATED POTENTIALLY ERRATIC WIND.
* PSBL FOG DEVELOPMENT OVERNIGHT INTO EARLY TUE.
ZEBIC
//DISCUSSION...UPDATED 18Z...
WARM AND HUMID CONDITIONS IN PLACE ALONG WITH VARIOUS BOUNDARIES TO
KEEP NEXT ROUND OF SHRA/TSRA IN THE FORECAST INTO THIS EVENING.
ATMOSPHERE TO CONTINUE TO RECOVER FROM MORNING CONVECTIVE ACTIVITY.
THINKING IS A FEW TSRA ARE POSSIBLE BY MID AFTERNOON IN AREAS OF
LESSENING/THINNING OF CLOUD COVER AND MAY EXPAND IN COVERAGE BY LATE
AFTERNOON IF MORE WIDESPREAD SUNSHINE OCCURS. CIRROSTRATUS SHIELD
ASSOCIATED WITH ORGANIZED AREAS OF TSRA/SHRA OVER IA MAY LIMIT
AMOUNT/DURATION OF SUN. TSRA CLUSTERS OVER IA EXPECTED TO ORGANIZE
FURTHER AND TRACK ACROSS NORTHERN ILLINOIS AND POSSIBLY NORTHWEST
INDIANA INTO THE EVENING.
SURFACE WARM FRONT EXPECTED TO REMAIN IN THE VICINITY OR JUST SOUTH
OF THE TERMINALS. GIVEN HUMID ATMOSPHERE AND ADDITIONAL RAINFALL
AREAS OF MAINLY LIGHT FOG ARE LIKELY OVERNIGHT.
ZEBIC
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE IN SHRA/TSRA...MEDIUM CONFIDENCE IN PRECISE
TIMING/COVERAGE.
* HIGH CONFIDENCE IN WIND FORECAST.
* LOW CONFIDENCE IN OVERNIGHT FOG DEVELOPMENT REDUCING VSBYS.
ZEBIC
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT THROUGH FRIDAY...PERIODIC CHANCES FOR
THUNDERSTORMS. OTHERWISE EXPECT VFR CIGS.
FRIDAY AND SATURDAY...CHANCE FOR SHOWERS. MAINLY VFR.
SUNDAY...VFR.
BEACHLER
&&
.MARINE...
411 PM CDT
HIGH PRESSURE REMAINS PARKED OFF THE CAROLINA COASTWHILE LOW
PRESSURE CONTINUES TO DRIFT NORTHWARD ACROSS CENTRAL MANITOBA AND
ONTARIO. ADDITIONAL LOW PRESSURE WILL DEVELOP FROM THE CANADIAN
PRAIRIES TO THE NORTHERN PLAINS TUESDAY AND MOVE EASTWARD INTO
WEDNESDAY WITH A CLOSED LOW DEVELOPING OVER THE WESTERN GREAT LAKES
BY WEDNESDAY NIGHT. A LARGER LOW WILL DEVELOP IVER THE GREAT LAKES
LATER FRIDAY AND LIKELY LINGER THROUGH THE WEEKEND BEFORE HIGH
PRESSURE BUILDS IN FROM THE WEST EARLY NEXT WEEK. SOUTHERN WINDS
WILL BE IN PLACE INTO WEDNESDAY WHEN THE FIRST SFC LOW PASSES WHICH
WILL TURN WINDS WEST AND NORTHWEST. SPEEDS WILL FLUCTUATE UP AND
DOWN UNTIL THE LOW PASSES SIMILAR TO PREVIOUS DAYS. A STABLE AIR
MASS OVER THE WATER WILL KEEP AREAS OF DENSE FOG GOING ACROSS MUCH
OF THE NORTHERN PART OF THE LAKE INTO TUESDAY AND PROBABLY INTO
WEDNESDAY FOR THAT MATTER SO THE DENSE FOG ADVISORY MAY NEED TO BE
EXTENDED. WIND SPEEDS LOOK TO REMAIN ON THE LIGHER SIDE FROM
WEDNESDAY THROUGH THE WEEKEND WITH A FAIRLY BAGGY PRESSURE GRADIENT
DEVELOPING AND THE DIRECTION WILL LIKELY VARY FROM WEST TO NORTH.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ008-ILZ010-ILZ011-ILZ019
UNTIL 7 AM TUESDAY.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565
UNTIL 10 AM TUESDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS LINCOLN IL
1201 PM CDT MON JUN 24 2013
.DISCUSSION...
ISSUED 1028 AM CDT MON JUN 24 2013
HAVE MADE ONLY MINOR CHANGES TO GRIDS AND ZFP THIS MORNING TO
REFLECT THE CONTINUED POTENTIAL FOR THE REDEVELOPMENT OF SHOWERS
AND THUNDERSTORMS NORTH OF I-74. HRRR RUNS CONTINUE TO ALTERNATE
BETWEEN LOW POPS FOR THE REMAINDER OF THE DAY AND AN MCS ROLLING
ACROSS THE REGION. WITH SHORTWAVE NOW MOVING ACROSS IOWA COMBINING
WITH ANTECEDENT BOUNDARIES AND ABUNDANT PRECIP WATER...OVER 2
STANDARD DEVIATIONS ABOVE CLIMATOLOGY...HAVE INCREASED POPS NORTH
OF I-74 AND LOWERED HIGHS THERE. HAVE ALSO MADE SOME ADJUSTMENTS
TO REFLECT ONLY SCATTERED CLOUDS IN KIJX/KSPI AREA.
BARKER
&&
.AVIATION...
ISSUED 1201 PM CDT MON JUN 24 2013
DIFFICULT TO DELINEATE DETAILS IN THIS AFTERNOONS FORECAST. LOTS
OF PLAYERS IN THE GAME THIS TIME AROUND. SHORTWAVE CROSSING IOWA
IS CURRENTLY PRODUCING STRONG TO SEVERE CONVECTION. AS THE FORCING
PUSHES EAST IT WILL INTERACT WITH RESIDUAL BOUNDARIES ACROSS
ILLINOIS FROM LAST NIGHTS DOWNPOURS. ABUNDANT MOISTURE EVIDENT
WITH 2+ STANDARD DEVIATION PRECIP WATER VALUES IN PLACE. HOWEVER...MODELS
ARE FORECASTING SOME WARMING AT MID-LEVELS WHICH MAY LIMIT COVERAGE
OF CONVECTION BY THE TIME IT REACHES CENTRAL ILLINOIS TAF SITES.
FOR NOW WILL ASSUME THAT COLD POOL BEHIND INCOMING CONVECTION WILL
BE SUFFICIENT TO COMPENSATE FOR ANY FORECASTED WARMING AND WILL
HIT CONVECTION HARD...PARTICULARLY IN THE WESTERN TERMINALS LATE
THIS AFTERNOON AND EARLY EVENING.
IN SHORT-TERM...A PACKET OF GRAVITY WAVES IS PUSHING SOUTH THROUGH
CENTRAL ILLINOIS AT THIS TIME ENABLING SOME LOW CLOUDS TO BRIEFLY
IMPACT TERMINALS AND PRODUCING SOME WIND SHIFTS. WILL INCLUDE AS
MUCH DETAIL AS POSSIBLE...BUT SOME GENERALIZATIONS WILL BE NECESSARY.
BARKER
&&
.PREV DISCUSSION...
ISSUED 240 AM CDT MON JUN 24 2013
ONGOING PARADE OF MCS ACTIVITY AND ASSOCIATED HEAVY RAINFALL WILL
CONTINUE TO BE A CONCERN FOR A COUPLE MORE DAYS. LATEST MCS
COVERED A GOOD PORTION OF IOWA...ALBEIT A BIT SMALLER THAN RECENT
NIGHTS...AND WAS BEING FED BY 40-45 KNOT LOW LEVEL JET. HAVE HAD
SOME STRONG THUNDERSTORMS SPREADING INTO THE NORTHWEST CWA OVER
THE LAST COUPLE HOURS ALONG A VERY SUBTLE SURFACE BOUNDARY.
MESOSCALE VORTEX FROM SUNDAY CONVECTION OVER THE SOUTHEAST CWA
STILL EVIDENT ON RADAR IMAGERY JUST EAST OF MOUNT VERNON.
SHORT TERM...TODAY THROUGH WEDNESDAY...
AS THE CASE HAS BEEN OVER THE LAST FEW DAYS...MODEL SOLUTIONS ARE
FAIRLY VARIED WITH MESOSCALE FEATURES NOT HANDLED ESPECIALLY WELL.
MCV IS ROTATING SOUTHEAST AND ACTIVITY WITH THIS FEATURE SHOULD
BE OUT OF OUR AREA BY SUNRISE...SO AM PLANNING TO KEEP THE FAR
SOUTHEAST DRY THIS MORNING. FOCUS DURING THE MORNING WILL MORE BE
ACROSS THE NORTHWEST AND ANY INFLUENCES FROM LEFTOVER BOUNDARIES
AND NEWER ONES FROM THE CURRENT CONVECTION. WILL HAVE THE HIGHEST
POPS DURING THE AFTERNOON AS MORE OF THE DAYTIME HEATING IS A
FACTOR. PRECIPITABLE WATER VALUES AROUND 1.7 TO 1.8 INCHES POINT
TO SOME HEAVY DOWNPOURS AGAIN...ALTHOUGH CENTRAL PARTS OF THE CWA
ARE MORE ABLE TO HANDLE THE HEAVY RAIN THAN THE SOUTHEAST...WHERE
1-HOUR FLASH FLOOD GUIDANCE IS ONLY AROUND A HALF INCH FROM
EFFINGHAM TO FLORA. MAIN SEVERE WEATHER RISK WILL BE WEST OF I-55
THIS AFTERNOON WHERE 0-6KM SHEAR EXPECTED TO INCREASE TO AROUND 40
KNOTS...ALTHOUGH A PULSE SEVERE STORM CANNOT BE RULED OUT
ELSEWHERE.
MAIN THUNDERSTORM FOCUS SHIFTS NORTHWARD LATE TONIGHT THROUGH
TUESDAY NIGHT. WITH MORE SUNSHINE...TUESDAY SHOULD BE THE HOTTEST
DAY OF THE WEEK WITH HEAT INDEX VALUES AT OR JUST ABOVE 100. HAVE
SOME CONCERN FOR SIMILAR VALUES WEDNESDAY...ALTHOUGH THIS WILL
DEPEND ON TIMING OF A FRONTAL PASSAGE AND ASSOCIATED
THUNDERSTORMS. MORE WIDESPREAD RISK OF SEVERE WEATHER EXPECTED ON
WEDNESDAY WHICH WOULD HELP TEMPER THE HIGHS SOMEWHAT. SOME
ADDITIONAL HEAVY RAIN LIKELY AGAIN ON WEDNESDAY WITH THE STORMS...
AS PWAT VALUES RISE BACK TO AROUND 1.8 INCHES.
LONG TERM...THURSDAY THROUGH SUNDAY...
UPPER RIDGING STILL PROGGED TO BUILD ACROSS THE WESTERN CONUS
DURING THE LATTER PART OF THE WEEK...WITH A SLOW COOLING TREND.
CYCLONIC FLOW OVER THE GREAT LAKES JUSTIFIES SOME LOW CHANCE POPS
OR SLIGHT CHANCES THURSDAY THROUGH FRIDAY...BUT THIS SHOULD FADE
AS HIGH PRESSURE BUILDS IN FROM THE NORTHWEST OVER THE WEEKEND.
GEELHART
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
400 PM CDT MON JUN 24 2013
...UPDATED FOR SYNOPSIS AND SHORT TERM DISCUSSION...
.SYNOPSIS...
ISSUED AT 353 PM CDT MON JUN 24 2013
A FAIRLY STRONG SHORTWAVE TROUGH BY LATE JUNE STANDARDS WAS
APPROACHING THE SOUTHERN AND CENTRAL HIGH PLAINS THIS AFTERNOON.
AHEAD OF THIS FEATURE, STRONG SURFACE TROUGH HAD DEVELOPED OVER THE
HIGH PLAINS, WITH STRONG SOUTHERLY WINDS ACROSS SOUTHWEST KANSAS.
ELEVATED CONVECTION IN ADVANCE OF THIS SYSTEM DEVELOPED THIS MORNING
EAST OF DODGE CITY AND THEN MOVED EAST AND WEAKENED. ANOTHER BATCH
OF ELEVATED CONVECTION DEVELOPED WEST OF A SURFACE DRYLINE IN
SOUTHEAST COLORADO AND MOVED INTO FAR SOUTHWEST KANSAS THIS
AFTERNOON. SURFACE BASED CONVECTION HAD NOT YET DEVELOPED AS OF 3
PM.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 353 PM CDT MON JUN 24 2013
THE SHORT RANGE HRRR DOES INDICATE STORMS DEVELOPING IN THE TEXAS
AND OKLAHOMA PANHANDLES THIS AFTERNOON AS UPPER LEVEL FORCING
AIDS IN LOW LEVEL CONVERGENCE ALONG THE DRYLINE. GIVEN THE FAIRLY
STRONG MID LEVEL FLOW FROM THE SOUTHWEST, THIS CONVECTION SHOULD
MOVE NORTHEASTWARD FAIRLY RAPIDLY INTO SOUTHWEST KANSAS THIS
EVENING. SURFACE BASED CAPE VALUES WERE APPROACHING 3000 J/KG FROM
THE TEXAS PANHANDLE INTO SOUTHWEST KANSAS AHEAD OF THE DRYLINE.
0-6 KM BULK SHEAR WAS APPROACHING 40 KTS IN THIS SAME AREA, BUT
LOW LEVEL SHEAR WAS VERY WEAK. GIVEN THE EXPECTED HIGH DEWPOINT
DEPRESSIONS AND RESULTANT HIGH CLOUD BASES, THE STORMS MAY DEVELOP
QUITE A BIT OF OUTFLOW, AND THIS MAY LIMIT THE SEVERITY AS FAR AS
HAIL SIZE IS CONCERNED (SINCE THE STORMS MAY NOT REMAIN AS
SUPERCELL STRUCTURES AS LONG). BUT HAIL AS LARGE AS GOLFBALLS IS
POSSIBLE WITH THE STRONGEST STORMS. IT IS UNCLEAR HOW ORGANIZED
THE STORMS WILL BE AND HOW WIDESPREAD AND HEAVY THE RESULTANT
RAINFALL WOULD BE. BUT STORM CHANCES WERE INCREASED TO 30-40% FOR
PARTS OF SOUTHWEST KANSAS INCLUDING DODGE CITY, JETMORE AND LARNED
GIVEN THE SIGNIFICANT FORCING AND SURFACE BASED CAPE.
AFTER THE AFOREMENTIONED SHORTWAVE TROUGH PASSES TONIGHT AND WITH
THE LOSS OF DAYTIME HEATING, STORM CHANCES WILL DIMINISH RAPIDLY BY
LATE EVENING. THE LOW LEVEL WINDS WILL BEGIN TO VEER AS WELL AND
THIS WILL RESULT IN THE AXIS OF DEEP MOISTURE SHIFTING EASTWARD.
SOUTHWEST WINDS AT 15 KTS EVEN LATE TONIGHT WILL PREVENT TEMPERATURES
FROM DROPPING BELOW THE LOWER 70S AT DODGE CITY, HAYS AND PRATT,
WITH ONLY SLIGHTLY COOLER READINGS NEAR THE COLORADO BORDER.
BEHIND THE SHORTWAVE TROUGH, A WEAK COLD FRONT WILL PROGRESS INTO
CENTRAL KANSAS TUESDAY AFTERNOON, WITH A TRAILING DRYLINE EAST OF
DODGE CITY AND INTO THE PANHANDLES. VERY HOT TEMPERATURES FROM 103
TO 106F ARE EXPECTED IMMEDIATELY BEHIND THE DRYLINE WHERE THE LOW
LEVEL AIR HAS MOVED DOWNSLOPE AND WARMED ADIABATICALLY. ONLY
SLIGHTLY COOLER AIR CAN BE EXPECTED IN FAR WESTERN KANSAS ON THE
HIGHER TERRAIN, AND BEHIND THE WEAK COLD FRONT FROM WAKEENEY TO
DIGHTON. THUNDERSTORMS ARE NOT EXPECTED TUESDAY AFTERNOON GIVEN
THE LACK OF FORCING IN THE WAKE OF THE SHORTWAVE TROUGH AND SINCE
THE LOW LEVEL MOIST AXIS WILL HAVE SHIFTED FURTHER EAST BY THE
TIME OF PEAK HEATING.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 336 PM CDT MON JUN 24 2013
ZONAL FLOW ALOFT WILL BE IN PLACE OVER THE LOWER 48 STATES AT THE
BEGINNING OF THE EXTENDED PERIOD. A SHORTWAVE TROUGH THAT IS NOW
MOVING THROUGH THE GREAT BASIN AND DESERT SOUTHWEST WILL BE EXITING
THE NORTHERN AND CENTRAL PLAINS TUESDAY EVENING. THIS SYSTEM WILL
BRING A WEAK FRONTAL BOUNDARY SOUTH ACROSS WESTERN KANSAS IN ITS
WAKE LATE TUESDAY AFTERNOON AND EVENING. PRECIPITATION CHANCES LOOK
FAIRLY SMALL GIVEN THE LACK OF UPPER SUPPORT AND A FAIRLY DRY
AIRMASS.
THROUGH THE MIDDLE PART OF THE WEEK, 500 MILLIBAR HEIGHTS WILL BE
BUILDING OVER THE WESTERN AND CENTRAL PART OF THE COUNTRY. WITH
INCREASING THICKNESS VALUES OVER WESTERN KANSAS WE SHOULD SEE
DAYTIME HIGH TEMPERATURES WARMING BACK UP TO AROUND OR ABOVE 100
DEGREES ESPECIALLY BY THURSDAY. THE UPPER RIDGE BECOMES MORE
AMPLIFIED OVER WESTERN NORTH AMERICA TOWARD THE UPCOMING WEEKEND
WITH UPPER LEVEL FLOW BECOMING MORE NORTHWESTERLY OVER THE CENTRAL
PLAINS. A WEAK FRONTAL BOUNDARY IS FORECAST TO MOVE SOUTH THROUGH
THE CENTRAL HIGH PLAINS EARLY FRIDAY WITH EASTERLY UPSLOPE FLOW
SETTING UP INTO THE EASTERN SLOPES OF THE ROCKIES. AFTERNOON
THUNDERSTORMS SHOULD DEVELOP OFF THE FRONT RANGE. GIVEN THE UPPER
LEVEL FLOW, SOME OF THESE COULD MOVE INTO FAR WESTERN KANSAS FRIDAY
EVENING.
THE UPPER LEVEL FLOW OVER THE CENTRAL PART OF THE COUNTRY BECOMES
EVEN MORE MERIDIONAL THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK.
THE MEDIUM RANGE MODELS HAVE ALL BEEN TRENDING IN THIS DIRECTION
THROUGH THE PAST FEW RUNS. THINK THAT THE CURRENT WEEK TWO OUTLOOK
SHOULD BE TRENDED BACK TO AT LEAST NEAR NORMAL TEMPERATURES FOR NOW
BUT BASED ON FORECAST TEMPERATURES, WE COULD BE EVEN COOLER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1256 PM CDT MON JUN 24 2013
A TROUGH OF LOW PRESSURE IN THE LEE OF THE ROCKIES WILL LEAD TO
STRONG SOUTH WINDS THROUGH TONIGHT, WITH 20-25 KTS TODAY AND 15KTS
TONIGHT. THE WINDS WILL GRADUALLY WEAKEN AND SHIFT TO THE WEST
AFTER 12Z TUESDAY AS THE SURFACE TROUGH PROGRESSES EASTWARD INTO
WESTERN KANSAS. THERE IS A SMALL CHANCE OF A THUNDERSTORM NEAR
KHYS AND KDDC THIS AFTERNOON AND EVENING. VFR CONDITIONS WILL
PERSIST ASIDE FROM THUNDERSTORMS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 74 105 69 101 / 40 0 0 0
GCK 72 104 65 101 / 20 0 0 0
EHA 70 103 66 101 / 10 0 0 0
LBL 74 105 68 104 / 20 0 0 0
HYS 74 104 70 101 / 30 0 0 0
P28 74 100 74 101 / 20 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 8 PM CDT THIS EVENING FOR KSZ030-031-043>046-
062>066-075>081-085>090.
RED FLAG WARNING UNTIL 9 PM CDT /8 PM MDT/ THIS EVENING FOR
KSZ061-062-074.
&&
$$
SYNOPSIS...FINCH
SHORT TERM...FINCH
LONG TERM...GERARD
AVIATION...FINCH
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1252 PM CDT MON JUN 24 2013
.UPDATE...
ISSUED AT 1251 PM CDT MON JUN 24 2013
UPDATED THE FORECAST TO ADD SCATTERED THUNDERSTORMS FOR MUCH OF
THE AREA FOR THE REST OF THE AFTERNOON. A SMALL WAVE WAS MOVING
NORTHEAST OUT OF NEW MEXICO AND HAS SUSTAINED CONVECTION FROM
SOUTHWEST KANSAS INTO NORTHEAST KANSAS. ATMOSPHERE REMAINS
UNSTABLE WITH PLENTY OF MOISTURE. WATER VAPOR SATELLITE SHOWING A
MOISTURE STREAMING NORTHEAST FROM MEXICO.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 352 AM CDT MON JUN 24 2013
ANOTHER DIFFICULT FORECAST AS MESOSCALE FEATURES CONTINUE TO DEFINE
CONVECTIVE POTENTIAL...AND ARE DIFFICULT TO FORECAST MORE THAN A FEW
HOURS OUT. FOR TODAY...SOUNDINGS SUGGEST WAVE LIFTING OUT OF
OK/CTRL KS MAY SATURATE MID LEVELS ENOUGH TO SUPPORT SOME ISOLATED
CONVECTION THIS MORNING...AND WILL LEAVE AN ISOLATED POP TO REFLECT
THIS. HRRR MODEL...WHICH HAS PERFORMED WELL IN THE MORNING RUNS THIS
WEEK...DEPICTS CONVECTIVE COMPLEX OVER SC NEBRASKA SLIDING SLIGHTLY
TO THE SE AND BACK-BUILD INTO OUR FORECAST AREA LATER THIS
MORNING. FRONTAL BOUNDARY HAS SHIFTED FARTHER NORTHWARD AND SUSPECT
COMPLEX WILL STAY NORTH OF THE FA. ALSO SHOULD CONSIDER OUTFLOW
MOVING SE OUT OF IOWA CONVECTION AND WHERE THAT MAY END UP ON THE
KS/MO BORDER THIS AFTERNOON. AT THIS TIME LESS CINH AND BETTER
DYNAMICS COME TOGETHER NORTH OF THE AREA. HAVE STARTED WITH A SILENT
POP IN THE NE COUNTIES AND WILL MONITOR FOR DEVELOPMENT. BREEZY
SOUTHERLY WINDS WILL BE NEAR BUT GENERALLY BELOW WIND ADVISORY
CRITERIA AND WILL HOLD OFF FOR NOW. HIGHS TODAY IN THE 90S FOLLOWED
BY WARM OVERNIGHT LOWS IN THE MIDDLE 70S. WITH ANOTHER COMPLEX
MOVING NORTH OF THE FORECAST AREA LATE MONDAY INTO EARLY
TUESDAY...WILL CARRY A SLIGHT CHANCE POP ACROSS THE FAR NORTHERN
COUNTIES AS MAY SEE SOME LATE NIGHT COLD POOL LLJ INTERACTION. 67
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 352 AM CDT MON JUN 24 2013
MID RANGE AND EXTENDED FORECAST (TUESDAY THROUGH SUNDAY)...
WARM...MUGGY...AND DRY CONDITIONS EXPECTED TO PERSIST THROUGH MOST OF
THE MID RANGE AND EXTENDED PERIOD. FOR TUESDAY AND WEDNESDAY THE MID
LEVEL RIDGE GETS SOMEWHAT FLATTENED OUT AND DEAMPLIFIED AS THE HIGH
PRESSURE EXPANDS ACROSS THE SOUTHERN PLAINS. EVENTUALLY...BY MID
WEEK THE RIDGE WILL BECOME CENTERED OVER THE FOUR CORNERS REGION OF
THE US...AND WILL BECOME MOVE AMPLIFIED AS THE WEEK PROGRESSES. WITH
THE EASTERN EDGE OF THE HIGH PRESSURE DOME IN THE VICINITY OF
NORTHEAST KANSAS EXPECT SOME MID LEVEL NWLY FLOW TO REMAIN OVER THE
FORECAST AREA...WHICH WILL BRING THE POTENTIAL FOR MCS DEVELOPMENT
WITHIN THE FLOW. FOR NOW WILL KEEP A MOSTLY DRY FORECAST THROUGH THE
EXTENDED PERIOD...WITH THE LONE EXCEPTION OF THURSDAY NIGHT WHERE
THE ECMWF AND GFS AGREE ON THUNDERSTORMS DEVELOPING ALONG THE
PERIPHERY OF THE RIDGE AND DROPPING SOUTH/SOUTHEASTWARD OUT OF SE
NEBRASKA INTO NE KANSAS. GIVEN THE LACK OF ANY STRONG SIGNAL OF
OBVIOUS LIFTING MECHANISMS WILL ONLY GO WITH A SLIGHT CHANCE FOR
SHOWERS AND THUNDERSTORMS FOR THAT PERIOD. OTHERWISE...EXPECT A
RATHER WARM AND MUGGY PERIOD FOR TUES THROUGH THURS AS DAY TIME
HIGHS WILL GENERALLY REACH THE MID TO UPPER 90S...WITH HEAT INDEX
VALUES RANGING BETWEEN 100 AND 105 ACROSS MOST OF THE FORECAST AREA.
TEMPERATURES WILL COOL OFF A BIT FOR THE END OF THE WORK WEEK
THROUGH THE WEEKEND...AS A SURFACE HIGH BRINGS COOLER AIR INTO
NORTHEAST KANSAS. EXPECT TEMPS FOR FRIDAY THROUGH MONDAY TO BE IN
THE UPPER 80S TO PERHAPS THE MID 90S.
JL
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1251 PM CDT MON JUN 24 2013
VFR CONDITIONS EXPECTED OUTSIDE OF CONVECTIVE ACTIVITY THROUGH THE
PERIOD. SOUTH WINDS WILL CONTINUE NEAR 16 KTS WITH HIGHER GUSTS.
CONVECTIVE OUTFLOW BOUNDARIES WILL AFFECT THE WIND DIRECTION AND
SPEED. ADDED VCTS FOR SCATTERED CONVECTION THAT MAY LAST UNTIL
23Z. WINDS WILL DECREASE SOME TONIGHT THEN INCREASE AGAIN AFTER
14Z TUESDAY.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...53
SHORT TERM...CRAVEN
LONG TERM...LEIGHTON
AVIATION...53
AREA FORECAST DISCUSSION
NWS CARIBOU ME
123 PM EDT MON JUN 24 2013
.SYNOPSIS...
UNSETTLED CONDITIONS WITH SCATTERED SHOWERS AND THUNDERSTORMS WILL
PERSIST THROUGH MID WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
1PM UPDATE...
ADDED ENHANCED WORDING FOR THUNDERSTORMS THIS EVENING IN NORTHERN
ZONES. STRONG THUNDERSTORMS IN QUEBEC WILL ADVECT TOWARDS THE
NORTHWESTERN PORTION OF THE STATE THIS EVENING. THE STORMS WILL
WEAKEN AS THEY CROSS THE FORECAST AREA THIS EVENING. BEST CHANCE
FOR THE STRONGER STORMS WILL BE IN NORTHERN SOMERSET...NORTHERN
PISCATAQUIS AND NORTHERN AROOSTOOK COUNTIES. IN A LINE DOES
FORM...WILL HAVE TO CONSIDER ADDING POPS TO SOUTHERN PISCATAQUIS
AND PENOBSCOT COUNTIES FOR THIS EVENING.
10AM UPDATE...
THE DECAYING MCS IS BRINGING SHOWERS TO HANCOCK AND WASHINGTON
COUNTIES AT THIS TIME AND WILL EXIT THE FORECAST AREA IN THE NEXT
FEW HOURS. SKIES WILL CLEAR FROM NW TO SE AS THE CLOUDS ASSOCIATED
WITH THE OLD MCS LEAVE THE STATE. THIS WILL PRODUCE HIGHS IN THE
MID TO UPPER 80S WITH UNCOMFORTABLE HUMIDITY. ADJUSTED HIGHS UP A FEW
DEGREES. DAYTIME HEATING WILL CREATE SOME DESTABILIZATION WITH THE
BEST CHANCES FOR STRONG STORMS IN THE REMOTE AREAS OF NORTHERN
SOMERSET...PISCATAQUIS AND AROOSTOOK COUNTIES THIS EVENING. STRONG
WIND GUSTS WOULD APPEAR TO BE THE BIGGEST THREAT. HOWEVER...WITH A
STRONG LLJ...HIGH PWATS AND WELL OVER 10K FT OF WARM CLOUD...HEAVY
RAIN IS ALSO A CONCERN.
UPDATE 0530L: DECAYING MCS HAS REACHED OUR FAR WRN ZONES ATTM.
THIS A LITTLE FASTER THAN ERLYR EXPECTED SO HAVE ADJUSTED POPS FOR
CURRENT AND EXPECTED TRENDS THRU THE AM HRS. REMAINDER OF THE FCST UNCHANGED...
DECAYING MCS OVR SRN QUEBEC ATTM ABOUT TO ENTER FAR WRN MAINE...
OTHERWISE...PARTLY TO MOSTLY CLOUDY SKIES ACROSS THE FA ATTM W/
SOME FOG ACROSS THE N. NOT MUCH CHANGE IN THE OVERALL PTRN ACROSS
OUR AREA LAST 24 HRS AT LEAST IN THE UPPER LEVELS OF THE ATMOS AS
BRISK WNW FLOW ALOFT PERSISTS W/ OCNL DISTURBANCES EMBEDDED IN
THIS FLOW. IN THE LOWER LEVELS - A VRY WARM AND HUMID SWRLY FLOW
IS NOW IN PLACE ACROSS THE ENTIRE REGION W/ TDS GENERALLY IN THE
LOWER TO MID 60S. THE DECAYING MCS IS SHOWN BY THE SHORTER TERM
MODELS SUCH AS THE RUC TO CONT TO MV ESEWRD AND HOLD TOGETHER ENUF
TO HAVE SOME IMPACT ON OUR WRN ZNS ERLY TDY THEN ACROSS OUR S
CENTRAL ZNS THRU THE AM HRS AND POPS ACROSS THESE AREAS WILL
REFLECT THIS. OTHERWISE...ANOTHER UPPER DISTURBANCE IS FCST TO
SLIDE ESEWRD ACROSS THE FA LATER TDY AND PROVIDE ANOTHER UPTICK IN
SHOWERS/TSTMS.
UNLIKE SUN...WHERE MOST ACTION WAS S OF THE AREA - APPEARS TDY
THAT THINGS HAVE SHIFTED A LITTLE FURTHER N W/ THE INTRUSION OF
THE WARMER AND MORE HUMID AIR. AS A RESULT...WILL CARRY MAINLY CHC
POPS ACROSS THE REMAINDER OF THE FA TDY INTO THIS EVE W/ ACTIVITY
EXPECTED TO AGAIN WEAKEN/DISSIPATE LATER THIS EVE AS THIS UPPER
DISTURBANCE MVS AWAY FROM THE REGION. THIS WILL SET THE STAGE FOR
MORE PATCHY FOG W/ THE FOG PROBABLY A LITTLE MORE WDSPRD THAN THIS
AM W/ THE HUMID AIRMASS PERSISTING. TEMPS TDY WILL BE A LITTLE
TRICKY... CLDS AND SHOWERS WILL NO DOUBT HAVE SOME IMPACT AND
PROBABLY KEEP MOST AREAS FROM REACHING FULL POTENTIAL TDY.
STILL...A LITTLE SUNSHINE FROM TIME TO TIME IS EXPECTED AND WILL
GO A LONG WAY IN HEATING THINGS UP SO WILL HANG ONTO HIGHS INTO
THE LOWER 80S N W/ MID TO PSBLY UPPER 80S CENTRAL AND INTERIOR
DOWN EAST...
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
PERIOD WILL BEGIN WITH A SURFACE HIGH SETUP IN THE ATLANTIC AND
BOUNDARY DRAPED JUST TO THE NORTH OF THE REGION. THE SURFACE HIGH
WILL CONTINUE TO PUMP WARM AND MOIST AIR INTO THE REGION. GUIDANCE
IS IN FAIR AGREEMENT WITH THE BOUNDARY AND SURFACE LOW BEGINNING
TO DROP SOUTH THROUGH THE DAY ON TUESDAY. THIS COMBINED WITH
BETTER UPPER LEVEL DYNAMICS WITH THE REGION LOCATED IN THE
FAVORABLE RIGHT ENTRANCE REGION OF UPPER LEVEL JET ENHANCING
DIVERGENCE ALOFT. ALSO WITH WARM AND MOIST UNSTABLE AIR IN PLACE
CAPE VALUES WILL BE GENERALLY BETWEEN 500 TO 1500 J/KG. THESE
DYNAMICS WILL MAKE IT POSSIBLE TO HAVE SOME MORE ENHANCED
THUNDERSTORM ACTIVITY TUESDAY AFTERNOON AND EVENING. RIGHT NOW
THINKING IS THERE WILL BE THE POTENTIAL FOR SMALL HAIL AND GUSTY
WINDS BUT THIS MAY NEED TO BE ENHANCED FURTHER IF DYNAMICS
CONTINUE TO COME TOGETHER. BEST CHANCES STILL LOOK TO BE ACROSS
THE NORTHERN AND CENTRAL PORTIONS OF THE REGION WHERE BEST
SUPPORTING DYNAMICS ARE PRESENT.
THERE IS SOME MODEL DIVERGENCE FOR WEDNESDAY WITH THE MOST OF
GUIDANCE WANTING TO KEEP THE LOW PRESSURE ACROSS THE REGION WHILE
THE 23/12Z ECMWF WANTS TO KEEP IT DRIER. RIGHT NOW WILL KEEP
DECENT CONSISTENCY WITH PREVIOUS FORECAST WITH MORE SHOWERY TYPE
ACTIVITY. TEMPERATURES FOR WEDNESDAY LOOK TO BE COOLER ALTHOUGH
THIS WILL BE HIGHLY DEPENDENT ON CLOUD COVER.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
THE GUIDANCE IS STILL A BIT DIVERGENT IN THE BEGINNING OF THE LONG
TERM PERIOD. THE 24/00Z GFS/GEM WANTS TO HOLD ON TO THE BOUNDARY
AND SURFACE LOW A BIT LONGER THAN THE 23/12Z ECMWF FOR WEDNESDAY
NIGHT. THEN WE WILL SEE ANOTHER STRONG UPPER LEVEL DISTURBANCE
ACROSS THE GREAT LAKES CONTINUE TO PROGRESS EAST. ALL THE LONG
RANGE GUIDANCE INDICATES THIS MOVING EAST BUT WITH SLIGHT DIFFERENCES
IN TIMING. GENERALLY IT LOOKS LIKE THIS SYSTEM WILL BEGIN
PROGRESSING INTO THE REGION THURSDAY AFTERNOON. RIGHT NOW THE
GUIDANCE ALSO WANTS INDICATE THIS UPPER LEVEL LOW BECOMING QUASI-
STATIONARY GENERALLY ACROSS THE GREAT LAKES AND OHIO VALLEY. THIS
WOULD KEEP THE REGION IN A ACTIVE PATTERN THROUGH MUCH OF THE LONG
TERM PERIOD. THIS QUASI-STATIONARY TROUGH SETUP IS ALSO GENERALLY
SUPPORTED BY THE 23/12Z GFS/ECMWF RESPECTIVE ENSEMBLE MEAN. HIGH
AND LOW TEMPERATURES FOR THE PERIOD WILL GENERALLY BE NEAR NORMAL.
&&
.AVIATION /17Z MONDAY THROUGH FRIDAY/...
NEAR TERM: VRBL CONDS ACROSS THE AREA THIS AM W/ SOME IFR IN FOG
ACROSS THE N TO VFR CONDS ACROSS THE S. EXPECT FOG TO DISSIPATE
ERLY THIS AM W/ PREDOM VFR CONDS TDY EXPECT OCNL MVFR TO BRIEF IFR
PSBL IN ANY SHOWERS/TSTMS. FOG WILL AGAIN BE A THREAT TNGT ALONG
W/ A CONTD CHC OF SHOWERS AND PSBL THUNDER...
SHORT TERM: MOST SITES LOOK TO STAY VFR THROUGH THE PERIOD WITH
THE EXCEPTION OF THOSE SITES THAT RECEIVE SHOWER AND THUNDERSTORM
ACTIVITY. THIS WILL BE MORE LIKELY FOR THE NORTHERN SITES.
&&
.MARINE...
NEAR TERM: WINDS/SEAS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT
ADVISORY LEVELS THRU TONIGHT. VISIBILITIES COULD BE REDUCED IN PATCHY
FOG TODAY AND IN MORE WDSPRD AREAS OF FOG TNGT.
SHORT TERM: MARINE: NO HEADLINES EXPECTED AT THIS TIME WITH SEAS
GENERALLY STAYING 2 TO 4 FT AND WINDS 10 TO 15 KT. VISIBILITIES
COULD BE REDUCED WITH SHOWERS.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...KHW/MCW
SHORT TERM...JORDAN
LONG TERM...JORDAN
AVIATION...KHW/MCW/JORDAN
MARINE...KHW/MCW/JORDAN
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
412 PM CDT Mon Jun 24 2013
.SHORT TERM...(This Evening through Tuesday Night)
Issued at 355 PM CDT MON JUN 24 2013
Main concern will be with potential for convection again tonight and
then increasing heat conditions Tuesday. Latest HRRR model shows shortwave
trough in synoptic flow to hold together as it moves into eastern
Kansas. Dynamics are fairly weak as this is just a ripple in the
nearly zonal flow over the region. However...there is some modest
instability and potential for a decent LLJ late tonight....so another
nocturnal MCS could move through...especially in northern zones where
mid level lapse rates favor better instability.
On Tuesday...there still is a chance in the afternoon in the northern
zones for some convection to fire as yet another very weak short wave
trough moves through. Also of concern is what might be left over in
terms of outflow boundaries from any activity tonight.
Therefore...will keep a chance in the northern zones for tomorrow.
Meanwhile the thermal ridge begins to build to the west with 850mb
temperatures into the middle and upper 20s deg C in western and
central kansas. As this thermal ridge moves towards the area...we
will see heat indices begin to edge up to low 100s. Will not issue
advisory for Tuesday but have mentioned it in the hazardous weather
outlook.
Tuesday night...yet another chance for some nocturnal MCS activity
mainly in the northeastern zones as the thermal ridge axis moves over
the western areas and should limit convection there.
.LONG TERM...(Wednesday through Monday)
Issued at 355 PM CDT MON JUN 24 2013
Beginning in the middle of the work week, the flattened zonal flow
across the nation will begin to amplify as the prevailing westerlies
begin to buckle across the U.S.A./Canadian border. The buckling in
the flow will be lead by a weak shortwave Wednesday, with our region
quickly finding itself in the the northwest flow as the ridge axis
of the amplifying ridge pops up to to our west. However, as the
weekend arrives the trough across the Great Lakes will gather some
energy, expanding enough to possibly but much of our forecast area
on the cool side of the still prevailing northwest flow.
The pattern for the week will dictate hot and humid conditions
through the middle of the work week, with Wednesday and Thursday
being particularly muggy and troublesome. Dew points will be
critical mid-week on determining the need for a heat advisory as
heat indices will be ranging in the low 100s. Currently, forecast
numbers are coming up just shy of criteria, though this currently
looks due to the fact that afternoon dew points will likely mix out
a little as the hot air advecting in aloft from the southwest will
also be a bit dry.
By Friday...temperatures are expected to back off a little from the
hot and humid readings of the previous few days as the trough over
the Great Lakes begins to dominate the eastern CONUS. Readings for
Friday will still reach in the 90s, but the humidity wont be as bad;
and for the weekend temperatures should range through the 80s.
As for precipitation, only true potential for more than isolated
storms looks to be focused on Thursday night into Friday morning as
the edge of the Great Lakes trough begins pushing back to the
southwest. Have kept POPs in the chance category owing to the
vagaries of forecast timing in a northwest flow.
&&
.AVIATION...(For the 18Z TAFS through 18Z Tuesday Afternoon)
Issued at 1221 PM CDT MON JUN 24 2013
An outflow boundary has moved through STJ and MCI temporarily
shifting winds to the NW however winds should back to the south by
19Z. Thunderstorms will be possible over STJ through 19Z with no
cig/vis restrictions. These storms will skirt MCI and there may be a
bit of development along the outflow boundary continuing the chance
for a thunderstorm at MCI, thusly have left VCTS in the MCI TAF
through 19Z. MKC should remain dry. Beyond the 19Z period, conds
should remain VFR at the terminals with gusty winds out of the south
through tonight. Gusts will diminish overnight but winds will remain
out of the south between 10-15kts. Winds will become gusty again by
mid morning tomorrow with sustained winds between 15-20kts and gusts
25-30kts.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
SHORT TERM...Adolphson/73
LONG TERM...Cutter
AVIATION...73
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
611 PM EDT MON JUN 24 2013
.SYNOPSIS...
HIGH PRESSURE OFF THE MIDDLE ATLANTIC COAST WILL CONTINUE TO
BRING A SOUTHERLY FLOW OF WARM AND HUMID AIR TO THE AREA THROUGH
MID WEEK. A WEAK COLD FRONT WILL STALL TO OUR NORTH ACROSS THE
CENTRAL GREAT LAKES TUESDAY. A STRONGER COLD FRONT WILL MOVE
ACROSS THE REGION THURSDAY NIGHT INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
BAND OF AFTERNOON CONVECTION LOST SUPPORT AND DISSIPATED ABOUT
HALFWAY ACROSS THE CWA. AIRMASS REMAINS SOMEWHAT UNSTABLE THE REST
OF THE NIGHT. HRRR AND RUC SHOW SOME OF THE CONVECTION OVER LWR MI
WITH A VERY WEAK S/W WORKING ESE INTO THE LERI AREA THIS EVENING
THEN SOME PART OF THE COMPLEX OVER NW IL MAKING IT AROUND THE LERI
AREA AROUND MIDNIGHT OR SO. WILL KEEP CHANCE POPS GOING BUT TRY AND
DEPICT SOME BETTER TIMING.
LOWS WILL BE ABOVE GUIDANCE BY A DEGREE OR TWO.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
NEW DAY...SAME CONCERNS. UPPER FLOW IS NOW FAIRLY ZONAL THANKS TO
THE FLATTENING RIDGE. MODELS SHOW AN UPPER TROF DEVELOPING TO OUR
WEST BY WEDNESDAY AND THEN MOVING INTO THE REGION THURSDAY. IT
THEN GETS TRAPPED IN THE AREA AND THEN REINFORCED FOR THE WEEKEND
BUT THAT WILL BE COVERED IN THE SECTION BELOW. FOR TUESDAY MODELS
SHOW CONTINUED DEEP MOISTURE ACROSS THE AREA WITH WEAK
DISTURBANCES ALOFT MOVING THROUGH THE AREA. EXPECTING MORE
COVERAGE THAN TODAY AND WILL HAVE LIKELY TO HIGH CHANCE ACROSS THE
NORTHERN TIER OF COUNTIES WITH 30-40% SOUTH. TUESDAY NIGHT INTO
WEDNESDAY MODELS SHOW THICKNESS PACKING NORTHWEST TO SOUTHEAST
ACROSS THE AREA WITH THE LIKELY GENERATION POINT FOR MCS
DEVELOPMENT TO OUR NORTHWEST. CONCERNED THAT WE HAVE CONVECTION
MOVE INTO THE AREA TUESDAY NIGHT FROM THE NORTHWEST LASTING INTO
WEDNESDAY. WILL HAVE LIKELY POPS NORTHWEST PA AND NERN OHIO AND
MID/HIGH CHANCE ELSEWHERE TUESDAY NIGHT AND EARLY WEDNESDAY. LAKE
WEDNESDAY WILL HAVE LIKELY POPS MOVING IN FROM THE NORTHWEST WITH
APPROACHING UPPER TROF. THURSDAY AN UPPER TROF REMAINS OVER THE
AREA WITH DEEP MOISTURE STILL IN PLACE SO WILL CONTINUE LIKELY
POPS CENTRAL AND EAST WITH CHANCE POPS WEST. TEMPS WELL ABOVE
NORMAL THROUGH MID WEEK AND THEN NEAR NORMAL THURSDAY.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
UPPER LEVEL TROUGH DIGS INTO THE CENTRAL GREAT LAKES ON FRIDAY THEN
AMPLIFIES AS IT SLOWLY PIVOTS EAST OVER THE WEEKEND. THIS WILL CAUSE
LOW PRESSURE AT THE SURFACE TO RETROGRADE TO THE WEST WITH A
CONTINUED CHANCE OF SHOWERS AND THUNDERSTORMS WITHIN THE BROAD
CYCLONIC FLOW THROUGH AT LEAST SATURDAY. WILL CARRY A 30-50 PERCENT
POP FOR FRIDAY AND SATURDAY WITH A DECREASING TREND FOR SUNDAY AS
DRIER AIR GETS WRAPPED INTO THE SYSTEM FROM THE WEST. HIGHS WILL BE
NEAR NORMAL ON FRIDAY...AROUND 80...BEFORE DROPPING BACK INTO THE
70S OVER THE WEEKEND. ADJUSTED HIGHS DOWN SEVERAL DEGREES FOR
SATURDAY/SUNDAY CLOSER TO RAW MODEL VALUES INSTEAD OF MEX GUIDANCE
WHICH IS LIKELY RUNNING TOO HIGH AS IT TRENDS TOWARDS CLIMO IN THE
LATER PERIODS.
&&
.AVIATION /19Z MONDAY THROUGH SATURDAY/...
SCATTERED THUNDERSTORMS HAVE DEVELOPED ALONG A BOUNDARY EXTENDING
FROM NEAR DETROIT TO WEST OF MANSFIELD AND COLUMBUS. THESE
THUNDERSTORMS ARE MOVING NORTHEAST AT APPROXIMATELY 20 MPH AND HAVE
TRIED TO TIME INTO THE TERMINALS BETWEEN 18-00Z EXCEPT FDY/ERI WHERE
CHANCES LOOK TO0 LOW. ANY THUNDERSTORM THAT REACHES A TERMINAL MAY
PRODUCE BRIEF HEAVY RAIN AND WIND GUSTS UP TO 35 KNOTS. VFR
CONDITIONS EXPECTED TO PERSIST OUTSIDE OF THUNDERSTORMS. TRYING TO
TIME ANY ADDITIONAL SHOWERS AND THUNDERSTORMS FOR LATER IN THE TAF
PERIOD IS DIFFICULT AND WILL DEPEND ON LEFT OVER BOUNDARIES AND
EVOLUTION OF UPSTREAM ACTIVITY. MODELS SUGGEST ANOTHER ROUND OF
SHOWERS AND SCATTERED THUNDERSTORMS MAY TRY TO MOVE SOUTHEAST OUT OF
MICHIGAN EARLY TUESDAY MORNING AND ADDED SHOWERS INTO THE MORE
FAVORED LOCATIONS. ALSO INCLUDED MVFR HZ/BR AT A FEW SITES BETWEEN
10-13Z GIVEN THE HIGH HUMIDITY.
.OUTLOOK...NON-VFR IN SCATTERED SHOWERS/THUNDERSTORMS AND EARLY
MORNING MIST/HAZE THROUGH SATURDAY.
&&
.MARINE...
SOUTHWEST FLOW WILL CONTINUE ON THE LAKE AHEAD OF LOW PRESSURE THAT
WILL EVENTUALLY APPROACH LATE WEDNESDAY FROM THE PLAINS. SPEEDS WILL
INCREASE TO 10-20 KNOTS FOR A PERIOD OF TIME BEFORE SLOWLY VEERING
TO THE NORTHWEST THURSDAY AND FRIDAY AS THE LOW SHIFTS TO THE
EASTERN GREAT LAKES.
TIMING OF THUNDERSTORMS WILL BE DIFFICULT OVER THE NEXT SEVERAL DAYS
WITH MULTIPLE ROUNDS OF CONVECTION EXPECTED...ESPECIALLY FROM
TUESDAY THROUGH THURSDAY. THUNDERSTORMS HAVE THE POTENTIAL TO BE
STRONG GIVEN THE HOT AND HUMID AIRMASS OVER THE REGION.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TK
NEAR TERM...TK/ADAMS
SHORT TERM...TK
LONG TERM...KEC
AVIATION...KEC
MARINE...KEC
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
324 PM EDT MON JUN 24 2013
.SYNOPSIS...
DISTURBANCES EMBEDDED IN ZONAL FLOW WILL CONTINUE TO INTERACT WITH
A WARM AND UNSTABLE AIRMASS TO BRING CHANCES FOR SHOWERS AND
THUNDERSTORMS TO THE AREA THROUGH MID WEEK. AN APPROACHING COLD
FRONT WILL BRING INCREASING CHANCES FOR PRECIPITATION STARTING
WEDNESDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
ZONAL FLOW HAS DEVELOPED ALOFT ACROSS THE OHIO VALLEY TODAY. A
WEAKENING COMPLEX OVERNIGHT ASSOCIATED WITH A DISTURBANCE EMBEDDED
IN THE ZONAL FLOW BROUGHT A CONVERGENT LOW LEVEL BOUNDARY TO THE
AREA LATE THIS MORNING AND HAS BEEN THE FOCUS FOR SHOWERS AND
THUNDERSTORMS THIS AFTERNOON. THIS ACTIVITY WILL CONTINUE EASTWARD
AND APPEARS THAT IT WILL REACH THE EASTERN EDGE OF THE FORECAST
AREA BY THIS EVENING. A LOT OF UNCERTAINTY IS LEFT BEHIND THIS
DEPARTING BAND OF CONVECTION...WITH SKIES CLEARING ACROSS THE
NORTHWESTERN HALF OF OF THE ILN AREA THIS AFTERNOON. A DECAYING
MCV ACROSS NORTHERN INDIANA MAY ACT AS A FOCUS FOR ADDITIONAL
CONVECTION ACROSS NORTHERN INDIANA LATE THIS AFTERNOON...AS THE
ATMOSPHERE DESTABILIZES IN THE WAKE OF THIS MORNINGS CLOUD COVER.
LAPS SOUNDINGS SHOW UP TO 3000 J/KG SFC BASED CAPE JUST TO THE
WEST OF OUR NORTHWESTERN ZONES...WITH THE RAP INDICATING THAT
DESTABILIZATION WILL CONTINUE INTO THE AFTERNOON AND EARLY
EVENING. THE BIG QUESTION BECOMES HOW MUCH FORCING WILL THERE BE
FROM THE DECAYING MCV...IF ANY...TO PRODUCE CONVECTION LATE THIS
AFTERNOON. WITH THIS UNCERTAINTY IN MIND...AM FORECASTING CHANCE
POPS TO MOVE INTO OUR NORTHWESTERN ZONES LATE THIS AFTERNOON AND
EVENING...IN CASE THIS CONVECTION DOES INITIATE.
ANY CONVECTION THAT DOES DEVELOP WILL LIKELY DIMINISH AROUND
SUNSET AS LOW LEVEL FLOW REMAINS WEAK ACROSS OUR AREA...NOT
SUPPORTIVE OF NOCTURNAL CONVECTION. SOME CONVECTION WILL PROBABLY
REMAIN ONGOING TO OUR NORTH AND NORTHWEST TONIGHT...WHERE LOW TO
MID LEVEL FLOW IS STRONGER.
TONIGHT WILL BE ANOTHER WARM ONE WITH THE WARM AND HUMID AIRMASS
IN PLACE. WENT JUST BELOW GUIDANCE BASED ON BIASES FOR THE PAST
COUPLE OF NIGHTS...WITH SOME A WARM BIAS IN THE MODELS BEING
NOTICED IN OUR TYPICALLY COOLER VALLEYS.
&&
.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
ANOTHER DISTURBANCE WILL FOLLOW IN THE WAKE OF TODAYS DISTURBANCE
ON TUESDAY. LATEST RAP/NAM/ARW INDICATE THIS DISTURBANCE WILL BE
CROSSING SOUTHERN LAKE MICHIGAN EARLY TUESDAY. THE QUESTION
IS HOW ARE MODELS HANDLING SOME WARMER AIR ALOFT MOVING INTO
THE REGION...AND ITS AFFECT ON A DEVELOPING A CAP ACROSS OUR AREA
TUESDAY. MOST MODELS ARE INDICATING A WEAK CAP AROUND 5 KFT AGL
BASICALLY SOUTH OF INTERSTATE 70 ON TUESDAY...WHICH WOULD LIMIT
AND CONVECTION FROM INITIATING AS THE DISTURBANCE PASSES TO OUR
NORTH TUESDAY AFTERNOON. THE NAM/SREF DO NOT BUY INTO THIS
SOLUTION...AND HAVE A MUCH WEAKER...AND BREAKABLE CAP IN PLACE.
BASED ON THE INHERENT UNCERTAINTIES IN THIS CURRENT CONVECTIVE
REGIME...AND THE FACT THAT A GOOD DEAL OF LOW LEVEL MOISTURE IS IN
PLACE...CANNOT RULE OUT CONVECTION IN THE SOUTH TUESDAY. WENT WITH
CHANCE POPS FOR ALL ZONES WITH 30 POPS IN THE SOUTH AND 40 POPS
MAINLY NORTH OF INTERSTATE 70. HIGH TEMPERATURES...BARRING ANY
DEBRIS CLOUDS TO START OFF WITH...WILL RISE INTO THE UPPER 80S TO
LOWER 90S DURING THE AFTERNOON.
UNCERTAINTY INCREASES EVEN FURTHER GOING INTO TUESDAY NIGHT...WITH
ADDITIONAL CONVECTION POSSIBLE MAINLY ACROSS THE NORTH AS UPPER
LEVEL ENERGY IMPULSES CONTINUE TO MOVE WEST TO EAST IN THE ZONAL
FLOW. KEPT POPS IN THE SLIGHT CHANCE TO CHANCE RANGE FOR NOW...IN
CASE SOME OF THIS CONVECTION MAKES IT INTO OUR FORECAST AREA
DURING THE OVERNIGHT TIME PERIOD. ANOTHER WARM NIGHT WILL RESULT
WITH THE CONTINUED WARM AIRMASS. AM ANTICIPATING ENHANCED CLOUD COVER
TUESDAY NIGHT WITH SOME CONVECTION TO OUR NORTH...AND POSSIBLE
RETURN FLOW CONTINUING INTO THE NIGHT. TEMPERATURES MAY ONLY
BOTTOM OUT IN THE LOWER 70S ACROSS MANY OF OUR ZONES...EXCEPT FOR
PERHAPS THE RURAL EASTERN ZONES.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
THERE ARE SOME MODEL DISCREPANCIES AS TO HOW MUCH IF ANY PCPN WILL
BE ONGOING WEDNESDAY MORNING. WILL TREND TOWARD A DRIER FORECAST AT
THE ONSET BUT HANG ON TO SOME LOWER POPS JUST TO COVER THE THREAT.
ASSUMING THERE ARE NOT TOO MANY LINGERING DEBRIS CLOUDS...WE SHOULD
THEN BE ABLE TO DESTABILIZE NICELY THROUGH THE AFTERNOON IF
TEMPERATURES CAN PUSH INTO THE UPPER 80S TO NEAR 90. THIS WOULD
RESULT IN ML CAPE VALUES IN THE 2000 TO POSSIBLY 3000 J/KG RANGE.
THE COMBINATION OF THIS AND SHORT WAVE ENERGY MOVING DOWN ACROSS THE
WESTERN GREAT LAKES INTO OUR AREA WEDNESDAY AFTERNOON INTO WEDNESDAY
NIGHT...SHOULD LEAD TO A DECENT CHANCE OF THUNDERSTORMS PUSHING IN
FROM THE NORTHWEST LATE IN THE DAY. WITH INCREASING DYNAMICS ACROSS
THE AREA AND FAVORABLE TIMING...THERE IS THE POSSIBILITY OF SOME
SEVERE STORMS...ESPECIALLY LATE WEDNESDAY AFTERNOON INTO WEDNESDAY
EVENING. PCPN CHANCES WILL THEN CONTINUE INTO THURSDAY AS THE COLD
FRONT MOVES THROUGH. HIGHEST POPS FOR THURSDAY WILL BE ACROSS OUR
EAST/SOUTHEAST...CLOSER TO THE UPPER LEVEL TROUGH AND WHERE THE COLD
FRONT WILL BE LAST TO MOVE THROUGH.
BUILDING RIDGE OVER THE WESTERN UNITED STATES WILL CONTINUE TO
CARVE OUT A TROUGH ACROSS THE EAST THROUGH THE REMAINDER OF THE LONG
TERM PERIOD. THIS WILL KEEP TEMPERATURES FAIRLY SEASONABLE FRIDAY
THROUGH MONDAY WITH HIGHS GENERALLY IN THE LOWER 80S. MODELS ARE
SHOWING VARIOUS WEAK SHORT WAVES PROGRESSING THROUGH THE TROUGH BUT
IT IS TOUGH TO PINPOINT ANY KIND OF TIMING. AS A RESULT...WITH THE
UPPER LEVEL TROUGH IN PLACE AND GIVEN THE TIME OF YEAR...THINK THE
BEST WAY TO GO IS TO TREND THE POPS DIURNAL BUT KEEP THEM ON THE LOW
SIDE THROUGH THE WEEKEND.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
CONVECTION WILL AFFECT TAF SITES THIS AFTERNOON INTO THIS EVENING.
IT APPEARS THAT CMH AND LCK WILL SEE A CLUSTER OF THUNDERSTORMS
EARLY THIS AFTERNOON. OTHER CONVECTION AIDED BY AN UPPER AIR
TROUGH MAY DEVELOP AND IMPACT OTHER TAF SITES...WHICH WILL THEN
DIE DOWN WITH LOSS OF DAYTIME HEATING. BR IS EXPECTED LATE TONIGHT
AT LUK AND ILN. LACK OF UPPER SUPPORT MAY LIMIT CONVECTIVE
FORMATION ON TUESDAY.
OUTLOOK...SHOWERS AND THUNDERSTORMS WILL OCCUR FROM WEDNESDAY
AFTERNOON THROUGH THURSDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...LATTO
NEAR TERM...LATTO
SHORT TERM...LATTO
LONG TERM...JGL
AVIATION...CONIGLIO
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
704 PM EDT MON JUN 24 2013
.SYNOPSIS...
A BERMUDA HIGH WILL REMAIN IN PLACE OFF THE ATLANTIC COAST THROUGH
THE WEEK...DRIVING PERSISTENT MOIST SOUTHERLY FLOW INTO THE REGION.
AFTERNOON SHOWERS AND THUNDERSTORMS WILL REMAIN A POSSIBILITY EACH
DAY. A COLD FRONT PASSAGE OVER THE WEEKEND WILL BRING AN INCREASE IN
RAIN CHANCES AND SLIGHTLY COOLER TEMPERATURES BEFORE CLEARING THE
AREA EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TUESDAY/...
AS OF 700 PM EDT MONDAY...OUTFLOW BNDRYS ARE WORKING INTO THE
UPSTATE AND NE GA FROM THE SOUTH...TRIGGERING SOME CONVECTION IN
THEIR WAKE. THERE IS ALSO SOME ACTIVITY ALONG THE BLUE
RIDGE...ESPECIALLY UP IN NORTH CAROLINA. I TRIMMED POPS BACK ACROSS
THE WRN NC PIEDMONT AND THE ERN FOOTHILLS AND THE NE PIEDMONT OF
SOUTH CAROLINA. SINCE THESE AREAS WERE WORKED OVER BY CONVECTION
THEY SHOULD ENJOY A QUIET EVENING. HOWEVER...LATER TONIGHT WE MAY
SEE CONVECTION DEVELOP ONCE AGAIN AS THE SEA BREEZE FRONT PUSHES IN
FROM THE SOUTH BETWEEN ABOUT MIDNIGHT AND 2 AM. LAST NIGHT THIS
HELPED TO KICK OFF SHOWERS AND STORMS...AND IF SOMETHING DOESN/T
WORK OVER THE SRN PART OF THE SC/GA PARTS OF THE FA...I/D EXPECT TO
SEE SOMETHING LIKE THAT AGAIN.
AS OF 435 PM EDT MONDAY...STRONG TO SEVERE STORMS ARE CONTINUING
ALONG THE I-40 CORRIDOR OF NORTH CAROLINA. OVER THE UPSTATE..NE GA
AND MOST OF THE NC MTNS ITS GENERALLY QUIET RIGHT NOW. HOWEVER...THE
AIRMASS IS QUITE UNSTABLE OVER THIS AREA AND AS OUTFLOW BNDRYS WORK
IN FROM THE SOUTH AND WEST WE SHOULD SEE MORE DEVELOPMENT INTO THE
EARLY EVENING HOURS. THEREFORE I HAVE POPS RAMPING BACK UP INTO THE
THE HIGH CHANCE RANGE IN A COUPLE HOURS.
AS OF 225 PM EDT...COVERAGE OF SHOWERS AND THUNDERSTORMS REMAINS
FAIRLY HIGH ACROSS THE ERN HALF OF THE CWFA IN THE LOWER 70S
DEWPOINT AIR EAST OF THE MOUNTAINS. WITH SFC BASED CAPE VALUES IN
THE 2000 TO 3000 J/KG RANGE ACROSS MUCH OF THE REGION...ANTICIPATE
ADDITIONAL DEVELOPMENT ON EARLIER OUTFLOWS...AND NEW DEVELOPMENT
ACROSS THE MOUNTAINS IN WEAK BL CONVERGENCE AND LIGHT SW UPSLOPE. A
FEW SEVERE STORMS REMAIN POSSIBLE GIVEN THE INSTABILITY...BUT DCAPE
VALUES ARE GENERALLY 900 J/KG OR LESS AND PROFILES FAIRLY MOIST...SO
IT WILL TAKE VERY TALL STORMS. WILL FEATURE MAINLY SOLID CHC TO LOW
LIKELY POPS FOR THE LATE AFTN HOURS...EXCEPT CATEGORICAL ON THE ERN
FRINGE.
UPPER FORCING WILL SLOWLY IMPROVE THROUGH THE PERIOD AS H5
TROUGHINESS CONTINUES ALONG THE SRN APPALACHIANS...WITH WEAK UPPER
DIVERGENCE SETTING UP OVER THE MTNS THROUGH TUE. LOW LEVEL SW FLOW
SHOULD PROVIDE SOME UPSLOPE ENHANCEMENT IN THE SW MTNS WHERE CHC
POPS WILL BE KEPT GOING THE LONGEST TONIGHT. SIGNALS ARE MIXED ON
LOW STRATUS DEVELOPMENT TUE MORNING GIVEN A MORE SW TO W DIRECTION
IN THE BL FLOW VERSUS THE SRLY WINDS OBSERVED THIS MORNING. EXPECT
MIN TEMPS TO BE QUITE WARM. THE UPPER FORCING...PWAT IN PROFILES
AROUND 1.75 INCHES...AND A DEVELOPING LEE TROUGH SHOULD GET LIKELY
COVERAGE GOING AGAIN EARLY ON TUESDAY...WITH SIMILAR HAZARDS OF
LOCALLY HEAVY RAINFALL AND AN ISOLD SEVERE THREAT. THICKNESSES
SUPPORT VERY WARM TEMPS NEAR 90 TUE AFTN IN THE PIEDMONT...BUT CLOUD
COVER AND PRECIP SHOULD CURB THAT SOMEWHAT.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
AS OF 230 PM MONDAY...THE SHORT TERM PERIOD LOOKS RATHER
ACTIVE...HIGHLIGHTED BY A SERIES OF UPPER LEVEL IMPULSES AIDING IN
DIURNAL CONVECTION...AND AN UPPER TROF DIVING THROUGH THE OHIO
VALLEY THROUGH THE END OF THE PERIOD. TUESDAY EVENING A PERSISTENT
BERMUDA HIGH WILL CONTINUE TO PROMOTE SOUTHERLY FLOW. MID TO UPPER
60S DEWPOINTS AND SURFACE TEMPERATURES IN THE 80S WILL CONTINUE TO
ALLOW FOR ENOUGH INSTABILITY FOR CONVECTION INTO THE EVENING HOURS.
THUS...KEPT SOLID CHANCE POPS THROUGH SUNSET. MEANWHILE...UPPER
LEVEL PATTERN BEGINS TO AMPLIFY SOMEWHAT AS TROF DEEPENS ACROSS THE
UPPER MIDWEST. AS THE DISTURBANCE MOVES EASTWARD THROUGH THE
GREAT LAKES REGION ON WEDNESDAY...HEIGHTS ACROSS NORTHEAST GEORGIA
AND THE CAROLINAS WILL BEGIN TO FALL. AS FLOW AT THE SURFACE
REMAINS SOUTHERLY...AND HEIGHTS FALL ALOFT...EXPECTING SOME RATHER
WIDESPREAD CONVECTION TO OCCUR WEDNESDAY AFTERNOON. BOTH GFS AND
NAM FORECAST SOUNDINGS INDICATE SUBSTANTIAL DRYING IN THE MID LEVELS
INTO THE AFTERNOON HOURS THUS STEEPENING LAPSE RATES.
LIKEWISE...SBCAPE VALUES NEARING 1500-2000J/KG CANNOT BE RULED
OUT...ESPECIALLY ACROSS THE HIGHER TERRAIN AND THE UPSTATE OF SC.
KEPT HIGH END CHANCE POPS ACROSS THE ENTIRE REGION WITH SLIGHTLY
HIGHER POPS OVER THE ABOVE MENTIONED AREAS. WITH ALL THAT
SAID...SHEAR PROFILES LOOK RATHER BLEAK AS FLOW THROUGH THE COLUMN
IS WEAK. THUS NOT EXPECTING ANY ROTATING STORMS...LEADING TO A MORE
DAMAGING WIND...LARGE HAIL...AND HEAVY RAINFALL THREAT. MOST IF NOT
ALL CONVECTION SHOULD CEASE BY NEAR OR SLIGHTLY AFTER SUNSET ON
WEDNESDAY EVENING AS DIURNAL HEATING IS LOST. TEMPERATURES WILL BE
SLIGHTLY ABOVE NORMAL FOR MOST AREAS ON WEDNESDAY.
AS THE UPPER TROF DIGS OUT ACROSS THE OHIO AND TENNESSEE RIVER
VALLEYS ON THURSDAY...UPPER LEVEL HEIGHTS WILL FALL FURTHER...AND A
SURFACE COLD FRONT WILL BE MOVING CLOSER TO THE REGION. EXPECTING
MUCH OF THE SAME ON THURSDAY AS SURFACE HEATING AND MODEST DEWPOINTS
WILL ALLOW FOR SUBSTANTIAL CAPE. HOWEVER ALTHOUGH NOT THAT
HIGH...THURSDAY WILL YIELD MORE SHEAR THAN WEDNESDAY AS THE TROF
BASE SWINGS THROUGH...AND THE COLD FRONT APPROACHES. THIS WILL LEAD
TO AT LEAST SOME POTENTIAL FOR BETTER CONVECTIVE ORGANIZATION. LOOK
FOR THE MAIN THREATS ON THURSDAY TO BE DAMAGING WINDS...LARGE
HAIL...AND HEAVY RAINFALL. CONVECTION WILL LIKELY BE MOST INTENSE
ALONG AND AHEAD OF THE FRONT DURING THE AFTERNOON HOURS. WENT WITH
LIKELY POPS EARLY IN THE DAY ACROSS THE HIGHER TERRAIN AND SOLID
CHANCE POPS ELSEWHERE. TEMPERATURES ON THURSDAY WILL BE AT OR
SLIGHTLY BELOW NORMAL AS THUNDERSTORM DEVELOPMENT WILL PLAY A MAJOR
ROLE.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 200 PM MONDAY...THE EXTENDED PERIOD BEGINS WITH THE CWA ON THE
FAR WESTERN PERIPHERY OF A BERMUDA HIGH AND AN UPPER LEVEL TROUGH
QUICKLY DEVELOPING OVER THE REGION ON THURSDAY. THE TROUGH DEEPENS
OVER THE WEEKEND AND TAKES OVER THE MAJORITY OF THE EASTERN
CONUS...WHILE A COLD FRONT APPROACHES WITH THE TROUGH AND THEN
STALLS OUT OVER THE AREA FOR THE WEEKEND. THE TROUGH REMAINS THE
DOMINANT FEATURE FOR MOST OF THE EXTENDED PERIOD...WITH HIGH
PRESSURE ONLY BEGINNING TO BUILD BACK IN TO THE WEST OF THE FORECAST
AREA BY EARLY NEXT WEEK. CONVECTION WILL BE MAINLY DIURNAL IN
NATURE...WITH ISOLATED TO SCATTERED COVERAGE OVER THE FOOTHILLS AND
MOUNTAINS EACH AFTERNOON. THE HIGHEST POPS WILL BE FEATURED EARLY IN
THE WEEKEND WITH THE FRONTAL PASSAGE. CLOUD COVER AND THE PERSISTENT
UPPER TROUGH WILL KEEP HIGH TEMPERATURES SLIGHTLY COOLER THAN
AVERAGE OVER THE WEEKEND...BUT NORTHWESTERLY FLOW FOLLOWING THE
FRONT WILL DRY OUT THE AIRMASS AND ALLOW A SLIGHT WARMING TREND BY
LATE WEEKEND/EARLY NEXT WEEK.
&&
.AVIATION /23Z MONDAY THROUGH SATURDAY/...
AT KCLT...THE TRAINING CLUSTER OF THUNDERSTORMS HAS SET UP MAINLY S
TO SE OF THE AIRFIELD THIS AFTN...BUT CLOSE ENOUGH TO CARRY WALL TO
WALL THUNDER THROUGH 00Z...WITH TEMPO GUSTS AND MVFR RESTRICTIONS IN
ANY HEAVIER RAINFALL. WE COULD SEE ADDITIONAL DEVELOPMENT FROM THE
FOOTHILLS LATER THIS AFTN/EVENING PER THE LATEST HRRR RUN.
CONFIDENCE IS LOWER ON THAT...SO WILL RAMP DOWN TO A VCSH FOR NOW.
CIGS AND VSBY ARE A REAL QUESTION MARK OVERNIGHT...WITH SOME STRATUS
LIKELY IN THE LOWER PIEDMONT...BUT WITH SW TO W BL FLOW PROVIDING
MUCH LESS OF A PUSH INTO THE TERMINAL AREA. WILL HINT THAT WAY WITH
SCT010 BUT KEEP CIGS AND VSBY VFR FOR NOW. EXPECT AN EARLY START TO
CONVECTION AGAIN ON TUE WITH VERY MOIST PROFILES AND SLIGHTLY
IMPROVING UPPER SUPPORT.
ELSEWHERE...THUNDERSTORMS ARE LIKELY AT TIMES AT ALL THE MTN AND
FOOTHILLS TAF LOCATIONS THIS AFTN AND EVENING. WILL RIDE ON SOME
FAIRLY BROAD VCTS GROUPS FOR NOW...BUT TEMPO WILL LIKELY BE NEEDED
AT TIMES LATER ON. EXPECT MAINLY VFR CIGS EXCEPT BRIEF MVFR IN ANY
TSTMS ALONG WITH BRIEFLY GUSTY WINDS. SCT SHRA OR TSRA COULD
CONTINUE INTO THE OVERNIGHT HOURS...BUT WITH THE BEST FOCUS IN SW
MTN UPSLOPE AREAS...SO WILL ALLOW COVERAGE TO WANE FOR NOW. MTN
VALLEY FOG/CIG PROBLEMS LOOK LIKELY...WITH IFR AT KAVL BY 08Z. EAST
OF THE MTNS...CONFIDENCE IS LOWER GIVEN THE SW TO W BL FLOW. SOME
STRATUS SEEMS LIKELY TOWARD DAYBREAK...AND POSSIBLY VSBY ISSUES IF
THE TERMINALS SEE HEAVY RAINFALL LATE TODAY. EXPECT ANOTHER EARLY
START TO CONVECTION ON TUE WITH THE AIRMASS REMAINING VERY MOIST.
OUTLOOK...EXPECT UNSETTLED WEATHER AT THE TERMINAL LOCATIONS THROUGH
THE WEEK...WITH UPPER TROUGHINESS PERSISTING AND THEN DEEPENING MID
TO LATE WEEK. THIS SHOULD LEAD TO MORNING FOG/STRATUS
RESTRICTIONS...WITH MAINLY AFTN/EVENING TSRA EACH DAY.
CONFIDENCE TABLE...
23-05Z 05-11Z 11-17Z 17-23Z
KCLT HIGH 100% HIGH 98% HIGH 86% MED 60%
KGSP HIGH 100% HIGH 97% HIGH 100% HIGH 80%
KAVL HIGH 100% MED 65% MED 66% MED 75%
KHKY HIGH 100% HIGH 98% HIGH 95% HIGH 100%
KGMU HIGH 100% HIGH 97% HIGH 98% HIGH 80%
KAND HIGH 100% HIGH 100% HIGH 90% HIGH 80%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...VISIN
NEAR TERM...HG/MCAVOY
SHORT TERM...CDG
LONG TERM...VISIN
AVIATION...HG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
509 PM EDT MON JUN 24 2013
.SYNOPSIS...
A BERMUDA HIGH WILL REMAIN IN PLACE OFF THE ATLANTIC COAST THROUGH
THE WEEK...DRIVING PERSISTENT MOIST SOUTHERLY FLOW INTO THE REGION.
AFTERNOON SHOWERS AND THUNDERSTORMS WILL REMAIN A POSSIBILITY EACH
DAY. A COLD FRONT PASSAGE OVER THE WEEKEND WILL BRING AN INCREASE IN
RAIN CHANCES AND SLIGHTLY COOLER TEMPERATURES BEFORE CLEARING THE
AREA EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TUESDAY/...
AS OF 435 PM EDT MONDAY...STRONG TO SEVERE STORMS ARE CONTINUING
ALONG THE I-40 CORRIDOR OF NORTH CAROLINA. OVER THE UPSTATE..NE GA
AND MOST OF THE NC MTNS ITS GENERALLY QUIET RIGHT NOW. HOWEVER...THE
AIRMASS IS QUITE UNSTABLE OVER THIS AREA AND AS OUTFLOW BNDRYS WORK
IN FROM THE SOUTH AND WEST WE SHOULD SEE MORE DEVELOPMENT INTO THE
EARLY EVENING HOURS. THEREFORE I HAVE POPS RAMPING BACK UP INTO THE
THE HIGH CHANCE RANGE IN A COUPLE HOURS.
AS OF 225 PM EDT...COVERAGE OF SHOWERS AND THUNDERSTORMS REMAINS
FAIRLY HIGH ACROSS THE ERN HALF OF THE CWFA IN THE LOWER 70S
DEWPOINT AIR EAST OF THE MOUNTAINS. WITH SFC BASED CAPE VALUES IN
THE 2000 TO 3000 J/KG RANGE ACROSS MUCH OF THE REGION...ANTICIPATE
ADDITIONAL DEVELOPMENT ON EARLIER OUTFLOWS...AND NEW DEVELOPMENT
ACROSS THE MOUNTAINS IN WEAK BL CONVERGENCE AND LIGHT SW UPSLOPE. A
FEW SEVERE STORMS REMAIN POSSIBLE GIVEN THE INSTABILITY...BUT DCAPE
VALUES ARE GENERALLY 900 J/KG OR LESS AND PROFILES FAIRLY MOIST...SO
IT WILL TAKE VERY TALL STORMS. WILL FEATURE MAINLY SOLID CHC TO LOW
LIKELY POPS FOR THE LATE AFTN HOURS...EXCEPT CATEGORICAL ON THE ERN
FRINGE.
UPPER FORCING WILL SLOWLY IMPROVE THROUGH THE PERIOD AS H5
TROUGHINESS CONTINUES ALONG THE SRN APPALACHIANS...WITH WEAK UPPER
DIVERGENCE SETTING UP OVER THE MTNS THROUGH TUE. LOW LEVEL SW FLOW
SHOULD PROVIDE SOME UPSLOPE ENHANCEMENT IN THE SW MTNS WHERE CHC
POPS WILL BE KEPT GOING THE LONGEST TONIGHT. SIGNALS ARE MIXED ON
LOW STRATUS DEVELOPMENT TUE MORNING GIVEN A MORE SW TO W DIRECTION
IN THE BL FLOW VERSUS THE SRLY WINDS OBSERVED THIS MORNING. EXPECT
MIN TEMPS TO BE QUITE WARM. THE UPPER FORCING...PWAT IN PROFILES
AROUND 1.75 INCHES...AND A DEVELOPING LEE TROUGH SHOULD GET LIKELY
COVERAGE GOING AGAIN EARLY ON TUESDAY...WITH SIMILAR HAZARDS OF
LOCALLY HEAVY RAINFALL AND AN ISOLD SEVERE THREAT. THICKNESSES
SUPPORT VERY WARM TEMPS NEAR 90 TUE AFTN IN THE PIEDMONT...BUT CLOUD
COVER AND PRECIP SHOULD CURB THAT SOMEWHAT.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
AS OF 230 PM MONDAY...THE SHORT TERM PERIOD LOOKS RATHER
ACTIVE...HIGHLIGHTED BY A SERIES OF UPPER LEVEL IMPULSES AIDING IN
DIURNAL CONVECTION...AND AN UPPER TROF DIVING THROUGH THE OHIO
VALLEY THROUGH THE END OF THE PERIOD. TUESDAY EVENING A PERSISTENT
BERMUDA HIGH WILL CONTINUE TO PROMOTE SOUTHERLY FLOW. MID TO UPPER
60S DEWPOINTS AND SURFACE TEMPERATURES IN THE 80S WILL CONTINUE TO
ALLOW FOR ENOUGH INSTABILITY FOR CONVECTION INTO THE EVENING HOURS.
THUS...KEPT SOLID CHANCE POPS THROUGH SUNSET. MEANWHILE...UPPER
LEVEL PATTERN BEGINS TO AMPLIFY SOMEWHAT AS TROF DEEPENS ACROSS THE
UPPER MIDWEST. AS THE DISTURBANCE MOVES EASTWARD THROUGH THE
GREAT LAKES REGION ON WEDNESDAY...HEIGHTS ACROSS NORTHEAST GEORGIA
AND THE CAROLINAS WILL BEGIN TO FALL. AS FLOW AT THE SURFACE
REMAINS SOUTHERLY...AND HEIGHTS FALL ALOFT...EXPECTING SOME RATHER
WIDESPREAD CONVECTION TO OCCUR WEDNESDAY AFTERNOON. BOTH GFS AND
NAM FORECAST SOUNDINGS INDICATE SUBSTANTIAL DRYING IN THE MID LEVELS
INTO THE AFTERNOON HOURS THUS STEEPENING LAPSE RATES.
LIKEWISE...SBCAPE VALUES NEARING 1500-2000J/KG CANNOT BE RULED
OUT...ESPECIALLY ACROSS THE HIGHER TERRAIN AND THE UPSTATE OF SC.
KEPT HIGH END CHANCE POPS ACROSS THE ENTIRE REGION WITH SLIGHTLY
HIGHER POPS OVER THE ABOVE MENTIONED AREAS. WITH ALL THAT
SAID...SHEAR PROFILES LOOK RATHER BLEAK AS FLOW THROUGH THE COLUMN
IS WEAK. THUS NOT EXPECTING ANY ROTATING STORMS...LEADING TO A MORE
DAMAGING WIND...LARGE HAIL...AND HEAVY RAINFALL THREAT. MOST IF NOT
ALL CONVECTION SHOULD CEASE BY NEAR OR SLIGHTLY AFTER SUNSET ON
WEDNESDAY EVENING AS DIURNAL HEATING IS LOST. TEMPERATURES WILL BE
SLIGHTLY ABOVE NORMAL FOR MOST AREAS ON WEDNESDAY.
AS THE UPPER TROF DIGS OUT ACROSS THE OHIO AND TENNESSEE RIVER
VALLEYS ON THURSDAY...UPPER LEVEL HEIGHTS WILL FALL FURTHER...AND A
SURFACE COLD FRONT WILL BE MOVING CLOSER TO THE REGION. EXPECTING
MUCH OF THE SAME ON THURSDAY AS SURFACE HEATING AND MODEST DEWPOINTS
WILL ALLOW FOR SUBSTANTIAL CAPE. HOWEVER ALTHOUGH NOT THAT
HIGH...THURSDAY WILL YIELD MORE SHEAR THAN WEDNESDAY AS THE TROF
BASE SWINGS THROUGH...AND THE COLD FRONT APPROACHES. THIS WILL LEAD
TO AT LEAST SOME POTENTIAL FOR BETTER CONVECTIVE ORGANIZATION. LOOK
FOR THE MAIN THREATS ON THURSDAY TO BE DAMAGING WINDS...LARGE
HAIL...AND HEAVY RAINFALL. CONVECTION WILL LIKELY BE MOST INTENSE
ALONG AND AHEAD OF THE FRONT DURING THE AFTERNOON HOURS. WENT WITH
LIKELY POPS EARLY IN THE DAY ACROSS THE HIGHER TERRAIN AND SOLID
CHANCE POPS ELSEWHERE. TEMPERATURES ON THURSDAY WILL BE AT OR
SLIGHTLY BELOW NORMAL AS THUNDERSTORM DEVELOPMENT WILL PLAY A MAJOR
ROLE.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 200 PM MONDAY...THE EXTENDED PERIOD BEGINS WITH THE CWA ON THE
FAR WESTERN PERIPHERY OF A BERMUDA HIGH AND AN UPPER LEVEL TROUGH
QUICKLY DEVELOPING OVER THE REGION ON THURSDAY. THE TROUGH DEEPENS
OVER THE WEEKEND AND TAKES OVER THE MAJORITY OF THE EASTERN
CONUS...WHILE A COLD FRONT APPROACHES WITH THE TROUGH AND THEN
STALLS OUT OVER THE AREA FOR THE WEEKEND. THE TROUGH REMAINS THE
DOMINANT FEATURE FOR MOST OF THE EXTENDED PERIOD...WITH HIGH
PRESSURE ONLY BEGINNING TO BUILD BACK IN TO THE WEST OF THE FORECAST
AREA BY EARLY NEXT WEEK. CONVECTION WILL BE MAINLY DIURNAL IN
NATURE...WITH ISOLATED TO SCATTERED COVERAGE OVER THE FOOTHILLS AND
MOUNTAINS EACH AFTERNOON. THE HIGHEST POPS WILL BE FEATURED EARLY IN
THE WEEKEND WITH THE FRONTAL PASSAGE. CLOUD COVER AND THE PERSISTENT
UPPER TROUGH WILL KEEP HIGH TEMPERATURES SLIGHTLY COOLER THAN
AVERAGE OVER THE WEEKEND...BUT NORTHWESTERLY FLOW FOLLOWING THE
FRONT WILL DRY OUT THE AIRMASS AND ALLOW A SLIGHT WARMING TREND BY
LATE WEEKEND/EARLY NEXT WEEK.
&&
.AVIATION /21Z MONDAY THROUGH SATURDAY/...
AT KCLT...THE TRAINING CLUSTER OF THUNDERSTORMS HAS SET UP MAINLY S
TO SE OF THE AIRFIELD THIS AFTN...BUT CLOSE ENOUGH TO CARRY WALL TO
WALL THUNDER THROUGH 00Z...WITH TEMPO GUSTS AND MVFR RESTRICTIONS IN
ANY HEAVIER RAINFALL. WE COULD SEE ADDITIONAL DEVELOPMENT FROM THE
FOOTHILLS LATER THIS AFTN/EVENING PER THE LATEST HRRR RUN.
CONFIDENCE IS LOWER ON THAT...SO WILL RAMP DOWN TO A VCSH FOR NOW.
CIGS AND VSBY ARE A REAL QUESTION MARK OVERNIGHT...WITH SOME STRATUS
LIKELY IN THE LOWER PIEDMONT...BUT WITH SW TO W BL FLOW PROVIDING
MUCH LESS OF A PUSH INTO THE TERMINAL AREA. WILL HINT THAT WAY WITH
SCT010 BUT KEEP CIGS AND VSBY VFR FOR NOW. EXPECT AN EARLY START TO
CONVECTION AGAIN ON TUE WITH VERY MOIST PROFILES AND SLIGHTLY
IMPROVING UPPER SUPPORT.
ELSEWHERE...THUNDERSTORMS ARE LIKELY AT TIMES AT ALL THE MTN AND
FOOTHILLS TAF LOCATIONS THIS AFTN AND EVENING. WILL RIDE ON SOME
FAIRLY BROAD VCTS GROUPS FOR NOW...BUT TEMPO WILL LIKELY BE NEEDED
AT TIMES LATER ON. EXPECT MAINLY VFR CIGS EXCEPT BRIEF MVFR IN ANY
TSTMS ALONG WITH BRIEFLY GUSTY WINDS. SCT SHRA OR TSRA COULD
CONTINUE INTO THE OVERNIGHT HOURS...BUT WITH THE BEST FOCUS IN SW
MTN UPSLOPE AREAS...SO WILL ALLOW COVERAGE TO WANE FOR NOW. MTN
VALLEY FOG/CIG PROBLEMS LOOK LIKELY...WITH IFR AT KAVL BY 08Z. EAST
OF THE MTNS...CONFIDENCE IS LOWER GIVEN THE SW TO W BL FLOW. SOME
STRATUS SEEMS LIKELY TOWARD DAYBREAK...AND POSSIBLY VSBY ISSUES IF
THE TERMINALS SEE HEAVY RAINFALL LATE TODAY. EXPECT ANOTHER EARLY
START TO CONVECTION ON TUE WITH THE AIRMASS REMAINING VERY MOIST.
OUTLOOK...EXPECT UNSETTLED WEATHER AT THE TERMINAL LOCATIONS THROUGH
THE WEEK...WITH UPPER TROUGHINESS PERSISTING AND THEN DEEPENING MID
TO LATE WEEK. THIS SHOULD LEAD TO MORNING FOG/STRATUS
RESTRICTIONS...WITH MAINLY AFTN/EVENING TSRA EACH DAY.
CONFIDENCE TABLE...
20-02Z 02-08Z 08-14Z 14-20Z
KCLT HIGH 100% HIGH 100% HIGH 100% MED 79%
KGSP HIGH 100% HIGH 100% HIGH 99% HIGH 91%
KAVL HIGH 100% HIGH 81% MED 66% MED 69%
KHKY HIGH 100% HIGH 100% HIGH 85% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 99% HIGH 91%
KAND HIGH 100% HIGH 100% HIGH 94% HIGH 93%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...VISIN
NEAR TERM...HG/MCAVOY
SHORT TERM...CDG
LONG TERM...VISIN
AVIATION...HG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
237 PM EDT MON JUN 24 2013
.SYNOPSIS...
A BERMUDA HIGH WILL REMAIN IN PLACE OFF THE ATLANTIC COAST THROUGH
THE WEEK...DRIVING PERSISTENT MOIST SOUTHERLY FLOW INTO THE REGION.
AFTERNOON SHOWERS AND THUNDERSTORMS WILL REMAIN A POSSIBILITY EACH
DAY. A COLD FRONT PASSAGE OVER THE WEEKEND WILL BRING AN INCREASE IN
RAIN CHANCES AND SLIGHTLY COOLER TEMPERATURES BEFORE CLEARING THE
AREA EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TUESDAY/...
AS OF 225 PM EDT...COVERAGE OF SHOWERS AND THUNDERSTORMS REMAINS
FAIRLY HIGH ACROSS THE ERN HALF OF THE CWFA IN THE LOWER 70S
DEWPOINT AIR EAST OF THE MOUNTAINS. WITH SFC BASED CAPE VALUES IN
THE 2000 TO 3000 J/KG RANGE ACROSS MUCH OF THE REGION...ANTICIPATE
ADDITIONAL DEVELOPMENT ON EARLIER OUTFLOWS...AND NEW DEVELOPMENT
ACROSS THE MOUNTAINS IN WEAK BL CONVERGENCE AND LIGHT SW UPSLOPE. A
FEW SEVERE STORMS REMAIN POSSIBLE GIVEN THE INSTABILITY...BUT DCAPE
VALUES ARE GENERALLY 900 J/KG OR LESS AND PROFILES FAIRLY MOIST...SO
IT WILL TAKE VERY TALL STORMS. WILL FEATURE MAINLY SOLID CHC TO LOW
LIKELY POPS FOR THE LATE AFTN HOURS...EXCEPT CATEGORICAL ON THE ERN
FRINGE.
UPPER FORCING WILL SLOWLY IMPROVE THROUGH THE PERIOD AS H5
TROUGHINESS CONTINUES ALONG THE SRN APPALACHIANS...WITH WEAK UPPER
DIVERGENCE SETTING UP OVER THE MTNS THROUGH TUE. LOW LEVEL SW FLOW
SHOULD PROVIDE SOME UPSLOPE ENHANCEMENT IN THE SW MTNS WHERE CHC
POPS WILL BE KEPT GOING THE LONGEST TONIGHT. SIGNALS ARE MIXED ON
LOW STRATUS DEVELOPMENT TUE MORNING GIVEN A MORE SW TO W DIRECTION
IN THE BL FLOW VERSUS THE SRLY WINDS OBSERVED THIS MORNING. EXPECT
MIN TEMPS TO BE QUITE WARM. THE UPPER FORCING...PWAT IN PROFILES
AROUND 1.75 INCHES...AND A DEVELOPING LEE TROUGH SHOULD GET LIKELY
COVERAGE GOING AGAIN EARLY ON TUESDAY...WITH SIMILAR HAZARDS OF
LOCALLY HEAVY RAINFALL AND AN ISOLD SEVERE THREAT. THICKNESSES
SUPPORT VERY WARM TEMPS NEAR 90 TUE AFTN IN THE PIEDMONT...BUT CLOUD
COVER AND PRECIP SHOULD CURB THAT SOMEWHAT.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
AS OF 230 PM MONDAY...THE SHORT TERM PERIOD LOOKS RATHER
ACTIVE...HIGHLIGHTED BY A SERIES OF UPPER LEVEL IMPULSES AIDING IN
DIURNAL CONVECTION...AND AN UPPER TROF DIVING THROUGH THE OHIO
VALLEY THROUGH THE END OF THE PERIOD. TUESDAY EVENING A PERSISTENT
BERMUDA HIGH WILL CONTINUE TO PROMOTE SOUTHERLY FLOW. MID TO UPPER
60S DEWPOINTS AND SURFACE TEMPERATURES IN THE 80S WILL CONTINUE TO
ALLOW FOR ENOUGH INSTABILITY FOR CONVECTION INTO THE EVENING HOURS.
THUS...KEPT SOLID CHANCE POPS THROUGH SUNSET. MEANWHILE...UPPER
LEVEL PATTERN BEGINS TO AMPLIFY SOMEWHAT AS TROF DEEPENS ACROSS THE
UPPER MIDWEST. AS THE DISTURBANCE MOVES EASTWARD THROUGH THE
GREAT LAKES REGION ON WEDNESDAY...HEIGHTS ACROSS NORTHEAST GEORGIA
AND THE CAROLINAS WILL BEGIN TO FALL. AS FLOW AT THE SURFACE
REMAINS SOUTHERLY...AND HEIGHTS FALL ALOFT...EXPECTING SOME RATHER
WIDESPREAD CONVECTION TO OCCUR WEDNESDAY AFTERNOON. BOTH GFS AND
NAM FORECAST SOUNDINGS INDICATE SUBSTANTIAL DRYING IN THE MID LEVELS
INTO THE AFTERNOON HOURS THUS STEEPENING LAPSE RATES.
LIKEWISE...SBCAPE VALUES NEARING 1500-2000J/KG CANNOT BE RULED
OUT...ESPECIALLY ACROSS THE HIGHER TERRAIN AND THE UPSTATE OF SC.
KEPT HIGH END CHANCE POPS ACROSS THE ENTIRE REGION WITH SLIGHTLY
HIGHER POPS OVER THE ABOVE MENTIONED AREAS. WITH ALL THAT
SAID...SHEAR PROFILES LOOK RATHER BLEAK AS FLOW THROUGH THE COLUMN
IS WEAK. THUS NOT EXPECTING ANY ROTATING STORMS...LEADING TO A MORE
DAMAGING WIND...LARGE HAIL...AND HEAVY RAINFALL THREAT. MOST IF NOT
ALL CONVECTION SHOULD CEASE BY NEAR OR SLIGHTLY AFTER SUNSET ON
WEDNESDAY EVENING AS DIURNAL HEATING IS LOST. TEMPERATURES WILL BE
SLIGHTLY ABOVE NORMAL FOR MOST AREAS ON WEDNESDAY.
AS THE UPPER TROF DIGS OUT ACROSS THE OHIO AND TENNESSEE RIVER
VALLEYS ON THURSDAY...UPPER LEVEL HEIGHTS WILL FALL FURTHER...AND A
SURFACE COLD FRONT WILL BE MOVING CLOSER TO THE REGION. EXPECTING
MUCH OF THE SAME ON THURSDAY AS SURFACE HEATING AND MODEST DEWPOINTS
WILL ALLOW FOR SUBSTANTIAL CAPE. HOWEVER ALTHOUGH NOT THAT
HIGH...THURSDAY WILL YIELD MORE SHEAR THAN WEDNESDAY AS THE TROF
BASE SWINGS THROUGH...AND THE COLD FRONT APPROACHES. THIS WILL LEAD
TO AT LEAST SOME POTENTIAL FOR BETTER CONVECTIVE ORGANIZATION. LOOK
FOR THE MAIN THREATS ON THURSDAY TO BE DAMAGING WINDS...LARGE
HAIL...AND HEAVY RAINFALL. CONVECTION WILL LIKELY BE MOST INTENSE
ALONG AND AHEAD OF THE FRONT DURING THE AFTERNOON HOURS. WENT WITH
LIKELY POPS EARLY IN THE DAY ACROSS THE HIGHER TERRAIN AND SOLID
CHANCE POPS ELSEWHERE. TEMPERATURES ON THURSDAY WILL BE AT OR
SLIGHTLY BELOW NORMAL AS THUNDERSTORM DEVELOPMENT WILL PLAY A MAJOR
ROLE.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 200 PM MONDAY...THE EXTENDED PERIOD BEGINS WITH THE CWA ON THE
FAR WESTERN PERIPHERY OF A BERMUDA HIGH AND AN UPPER LEVEL TROUGH
QUICKLY DEVELOPING OVER THE REGION ON THURSDAY. THE TROUGH DEEPENS
OVER THE WEEKEND AND TAKES OVER THE MAJORITY OF THE EASTERN
CONUS...WHILE A COLD FRONT APPROACHES WITH THE TROUGH AND THEN
STALLS OUT OVER THE AREA FOR THE WEEKEND. THE TROUGH REMAINS THE
DOMINANT FEATURE FOR MOST OF THE EXTENDED PERIOD...WITH HIGH
PRESSURE ONLY BEGINNING TO BUILD BACK IN TO THE WEST OF THE FORECAST
AREA BY EARLY NEXT WEEK. CONVECTION WILL BE MAINLY DIURNAL IN
NATURE...WITH ISOLATED TO SCATTERED COVERAGE OVER THE FOOTHILLS AND
MOUNTAINS EACH AFTERNOON. THE HIGHEST POPS WILL BE FEATURED EARLY IN
THE WEEKEND WITH THE FRONTAL PASSAGE. CLOUD COVER AND THE PERSISTENT
UPPER TROUGH WILL KEEP HIGH TEMPERATURES SLIGHTLY COOLER THAN
AVERAGE OVER THE WEEKEND...BUT NORTHWESTERLY FLOW FOLLOWING THE
FRONT WILL DRY OUT THE AIRMASS AND ALLOW A SLIGHT WARMING TREND BY
LATE WEEKEND/EARLY NEXT WEEK.
&&
.AVIATION /19Z MONDAY THROUGH SATURDAY/...
AT KCLT...THE TRAINING CLUSTER OF THUNDERSTORMS HAS SET UP MAINLY S
TO SE OF THE AIRFIELD THIS AFTN...BUT CLOSE ENOUGH TO CARRY WALL TO
WALL THUNDER THROUGH 00Z...WITH TEMPO GUSTS AND MVFR RESTRICTIONS IN
ANY HEAVIER RAINFALL. WE COULD SEE ADDITIONAL DEVELOPMENT FROM THE
FOOTHILLS LATER THIS AFTN/EVENING PER THE LATEST HRRR RUN.
CONFIDENCE IS LOWER ON THAT...SO WILL RAMP DOWN TO A VCSH FOR NOW.
CIGS AND VSBY ARE A REAL QUESTION MARK OVERNIGHT...WITH SOME STRATUS
LIKELY IN THE LOWER PIEDMONT...BUT WITH SW TO W BL FLOW PROVIDING
MUCH LESS OF A PUSH INTO THE TERMINAL AREA. WILL HINT THAT WAY WITH
SCT010 BUT KEEP CIGS AND VSBY VFR FOR NOW. EXPECT AN EARLY START TO
CONVECTION AGAIN ON TUE WITH VERY MOIST PROFILES AND SLIGHTLY
IMPROVING UPPER SUPPORT.
ELSEWHERE...THUNDERSTORMS ARE LIKELY AT TIMES AT ALL THE MTN AND
FOOTHILLS TAF LOCATIONS THIS AFTN AND EVENING. WILL RIDE ON SOME
FAIRLY BROAD VCTS GROUPS FOR NOW...BUT TEMPO WILL LIKELY BE NEEDED
AT TIMES LATER ON. EXPECT MAINLY VFR CIGS EXCEPT BRIEF MVFR IN ANY
TSTMS ALONG WITH BRIEFLY GUSTY WINDS. SCT SHRA OR TSRA COULD
CONTINUE INTO THE OVERNIGHT HOURS...BUT WITH THE BEST FOCUS IN SW
MTN UPSLOPE AREAS...SO WILL ALLOW COVERAGE TO WANE FOR NOW. MTN
VALLEY FOG/CIG PROBLEMS LOOK LIKELY...WITH IFR AT KAVL BY 08Z. EAST
OF THE MTNS...CONFIDENCE IS LOWER GIVEN THE SW TO W BL FLOW. SOME
STRATUS SEEMS LIKELY TOWARD DAYBREAK...AND POSSIBLY VSBY ISSUES IF
THE TERMINALS SEE HEAVY RAINFALL LATE TODAY. EXPECT ANOTHER EARLY
START TO CONVECTION ON TUE WITH THE AIRMASS REMAINING VERY MOIST.
OUTLOOK...EXPECT UNSETTLED WEATHER AT THE TERMINAL LOCATIONS THROUGH
THE WEEK...WITH UPPER TROUGHINESS PERSISTING AND THEN DEEPENING MID
TO LATE WEEK. THIS SHOULD LEAD TO MORNING FOG/STRATUS
RESTRICTIONS...WITH MAINLY AFTN/EVENING TSRA EACH DAY.
CONFIDENCE TABLE...
18-24Z 00-06Z 06-12Z 12-18Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 90%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 94% MED 66% MED 71%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 95%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 95% HIGH 95%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...VISIN
NEAR TERM...HG
SHORT TERM...CDG
LONG TERM...VISIN
AVIATION...HG
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
314 PM MDT MON JUN 24 2013
.SHORT TERM...THIS EVENING THROUGH TUESDAY NIGHT
ISSUED AT 313 PM MDT MON JUN 24 2013
CURRENT SURFACE ANALYSIS SHOWS LOW PRESSURE OVER SOUTHEASTERN
MT...WITH WARM FRONT STRETCHING EAST-SOUTHEASTWARD ACROSS NORTHERN
SD. A DRYLINE HAS DEVELOPED SOUTH OF THE LOW ACROSS EASTERN WY.
UPPER LEVEL ANALYSIS SHOWS LOW OVER SOUTHWESTERN ONTARIO...WITH
ANOTHER LOW OFF THE PACIFIC NW COAST. SOUTHWEST FLOW ALOFT IS IN
PLACE ACROSS THE REGION...WITH IMBEDDED SHORTWAVE ENERGY CROSSING
THE REGION. THE NEXT SHORTWAVE UPSTREAM IS MOVING EAST-NORTHEAST
ACROSS CENTRAL AND EASTERN PORTIONS OF WY. REGIONAL RADARS SHOWING
SOME SHOWERS AND STORMS DEVELOPING ACROSS EASTERN WY INTO FAR
WESTERN NEB AND SOUTHWESTERN SD. SKIES ARE PARTLY CLOUDY/MOSTLY
SUNNY ACROSS THE AREA WITH TEMPS GENERALLY IN THE 80S. SOUTH TO
SOUTHEAST WINDS CONTINUE TO BRING LOW LEVEL MOISTURE INTO THE
AREA...WITH DEWPOINTS IN THE UPPER 50S TO MID 60S ACROSS MUCH OF
THE PLAINS RIGHT NOW.
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS CAN BE EXPECTED LATE
TODAY INTO THIS EVENING AS SHORTWAVE ENERGY CROSSES THE AREA. THE
BEST CHANCES FOR PCPN STILL LOOK TO BE ACROSS SOUTHWESTERN INTO
CENTRAL SD. WITH INSTABILITY INCREASING THROUGH LATE TODAY THERE
WILL BE ISOLATED STRONG TO SEVERE STORMS ACROSS THE AREA WITH
LARGE HAIL AND STRONG WIND GUSTS. SHEAR WILL BE ADEQUATE FOR
POSSIBLE SUPERCELLS AS WELL. THE ACTIVITY COULD ORGANIZE INTO AN MCS
THIS EVENING OVER EASTERN PORTIONS OF THE AREA. SHOWERS AND STORMS
WITH THIS WAVE SHOULD GENERALLY END OVER THE CWA BY 06Z.
HOWEVER...ISOLATED SHOWERS/STORMS COULD DEVELOP ACROSS NORTHERN
PORTIONS OF THE CWA LATE TONIGHT AS SOUTHERLY LOW LEVEL JET
INTENSIFIES OVER THE AREA AHEAD OF APPROACHING COLD FRONT.
COLD FRONT WILL MOVE THROUGH THE AREA FROM WEST TO EAST LATE TONIGHT
AND TUESDAY MORNING. THE FRONT COULD STALL OUT OVER SOUTH CENTRAL SD
TUESDAY AFTERNOON. ANY CHANCES FOR SHOWERS AND THUNDERSTORMS SHOULD
BE LIMITED TO NORTHERN AND EASTERN PORTIONS OF THE CWA...MAINLY
DURING THE LATE MORNING AND EARLY AFTERNOON HOURS. DRIER AIR WILL
BUILD IN BEHIND THE FRONT. HOWEVER...NOT MUCH IN THE WAY OF COOLER
AIR IS EXPECTED. HIGHS WILL STILL BE IN THE UPPER 70S AND 80S...WITH
A FEW LOCATIONS AROUND SOUTH CENTRAL SD REACHING 90 DEGREES. BREEZY
TO WINDY NORTHWESTERLY WINDS WILL DEVELOP BEHIND THE FRONT...
ESPECIALLY ACROSS THE NORTHWESTERN AND WEST CENTRAL SD PLAINS. SKIES
WILL BECOME MAINLY CLEAR LATE IN THE DAY WITH DECREASING WIND DURING
THE EVENING.
&&
.LONG TERM...WEDNESDAY THROUGH MONDAY
ISSUED AT 313 PM MDT MON JUN 24 2013
WESTERN ATLANTIC BLOCKING WITH A CONTINUED DEEP NEGATIVE HEIGHT
ANOMALY OVER THE NORTHERN PAC WILL FAVOR A NEAR OMEGA BLOCK OVER
NOAM...WITH A STAUNCH WESTERN NOAM RIDGE EXPECTED. THIS WILL KEEP
THE REGION IN MAINLY DRY NW FLOW. HOWEVER...A RIDGE TOPPING
DISTURBANCE CANNOT BE RULED OUT TOWARD THIS WEEKEND AS INDICATED
IN THE ECMWF. THE QUESTION REMAINS WHETHER THE RIDGE WILL REMAIN
OVER WESTERN NOAM OR BEING TO SHIFT EAST AS SIGNALED IN THE MEAN
GEFS. EITHER WAY...A DRY FORECAST IS FAVORED ATTM. IN
ADDITION...THE REGION WILL REMAIN ON THE EDGE OF THE ASSOCIATED
THERMAL RIDGE...WITH TEMPS IN THE 90S POSSIBLE AT TIMES...EVEN
WARMER BY EARLY NEXT WEEK IF THE RIDGE DOES SHIFT EAST.
OVERALL...VERY LITTLE CHANGE MADE TO THE PREVIOUS FORECAST. WILL SIDE
SLIGHTLY BELOW GUIDANCE MOST OF THE PERIOD GIVEN THE CONTINUED
WARM MODEL BIAS OF LATE...LIKELY FUELED BY ONGOING GREEN AND MOIST
CONDITIONS. RETAINED LOW POPS THIS WEEKEND...WITH DRY CONDITIONS
OTHERWISE
&&
.AVIATION...FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING
ISSUED AT 313 PM MDT MON JUN 24 2013
A STRONG UPPER LEVEL DISTURBANCE AND ASSOCIATED SFC TROUGH WILL
ADVECT THROUGH THE REGION TODAY...SUPPORTING TS DEVELOPMENT THIS
AFTERNOON/EVENING...POSSIBLY SEVERE. STRONG CAPPING MAY LIMIT
STORMS TO DISCRETE SUPERCELLS. HOWEVER...SOME HIRES MODEL
SOLUTIONS FAVOR THE DEVELOPMENT OF A SQUALL LINE ACROSS WESTERN
SD...PROPAGATING EAST THROUGH THE SD PLAINS THIS EVENING. WILL
RETAIN PREVIOUS VCTS MENTION AT GCC AND WILL ADD TEMPO ON A NEED
BE BASIS. DID ADD A TEMPO AT RAP WHERE BETTER CHANCES FOR TS WILL
BE FOUND. MVFR TO IFR CIGS/VIS WOULD BE POSSIBLE WITH ANY
THUNDERSTORM. COLD FRONT WILL PROPAGATE THROUGH THE AREA TUES
MORNING...WITH WINDS SHIFTING NW AND BECOMING BREEZY AT
TIMES...ESP OVER THE SD PLAINS.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
SHORT TERM...26
LONG TERM...JC
AVIATION...JC
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
1132 AM MDT MON JUN 24 2013
.UPDATE...
ISSUED AT 941 AM MDT MON JUN 24 2013
CURRENT SURFACE ANALYSIS SHOWS LOW PRESSURE OVER FAR SOUTHEASTERN
MT...WITH WARM FRONT STRETCHING SOUTHEASTWARD ACROSS WESTERN SD.
UPPER LEVEL ANALYSIS SHOWS LOW OVER SOUTHWESTERN ONTARIO...WITH
ANOTHER LOW OFF THE PACIFIC NW COAST. SOUTHWEST FLOW ALOFT IS IN
PLACE ACROSS THE REGION...WITH IMBEDDED SHORTWAVE ENERGY OVER THE
REGION. ONE SHORTWAVE IS MOVING ACROSS EASTERN PORTIONS OF NEB AND
SD...WITH SHOWERS EXITING SOUTH CENTRAL SD. ANOTHER SHORTWAVE IS
NOTED OVER EASTERN UT AND NORTHWESTERN CO...MOVING NORTHEASTWARD
INTO SOUTHERN WY. SKIES ARE MOSTLY SUNNY ACROSS MUCH OF THE
AREA...WITH TEMPS IN THE UPPER 60S AND 70S. SOUTH TO SOUTHEAST
WINDS CONTINUE TO BRING INCREASING MOISTURE INTO THE AREA...WITH
DEWPOINTS IN THE UPPER 50S AND LOWER 60S ACROSS MUCH OF THE
PLAINS RIGHT NOW.
HAVE MADE MOSTLY MINOR UPDATES TO THE FORECAST FOR THE REST OF
TODAY AND INTO TONIGHT. REMOVED POPS FOR LATE THIS MORNING AND
ADJUSTED AFTERNOON POPS SLIGHTLY TO GIVE BETTER CHANCES FOR LATE
AFTERNOON. SHORTWAVE TO THE SOUTHWEST WILL PUSH INTO SOUTHWESTERN
PORTIONS OF THE CWA DURING THE MID AFTERNOON AND TRACK NORTHEAST
ACROSS THE AREA DURING THE LATE AFTERNOON AND EVENING. LOW
PRESSURE WILL REMAIN OVER NORTHWESTERN PORTIONS OF THE AREA INTO
THE AFTERNOON AND THEN SLOWLY MOVE EAST AS THE SHORTWAVE SLIDES
THROUGH. A DRY LINE WILL ALSO DEVELOP TO THE SOUTH OF THE LOW
ACROSS FAR EASTERN WY DURING THE AFTERNOON...HELPING TO AID IN
THUNDERSTORM DEVELOPMENT AS THE SHORTWAVE ARRIVES. THE BEST
CHANCES FOR PCPN LOOK TO BE ACROSS SOUTHWESTERN INTO CENTRAL SD
LATE THIS AFTERNOON AND EVENING. WITH INSTABILITY PROGGED TO BE
VERY HIGH LATE TODAY AND THIS EVENING...ESPECIALLY SOUTH AND EAST
OF THE BLACK HILLS...THERE WILL LIKELY BE A FEW STRONG TO SEVERE
STORMS ACROSS THE AREA...WITH LARGE HAIL AND STRONG WIND GUSTS.
SHEAR WILL BE ADEQUATE FOR ISOLATED SUPERCELLS AS WELL.
THE OTHER MAIN ADJUSTMENT TO THE FORECAST WAS TO RAISE HIGH TEMPS
A COUPLE OF DEGREES ACROSS AREAS SOUTH AND EAST OF THE BLACK HILLS
AS WARM FRONT LIFTS SLOWLY NORTH AND EAST DURING THE DAY.
&&
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
ISSUED AT 358 AM MDT MON JUN 24 2013
UPPER LEVEL ANALYSIS HAS WEAK RIDGING ACROSS THE NORTHERN AND
CENTRAL PLAINS WITH LARGE TROF OVER THE PACIFIC NORTHWEST. ONGOING
MCS IS PUSHING THROUGH CENTRAL NEBRASKA...AND LOOKS TO CLIP FAR
SOUTH CENTRAL SOUTH DAKOTA EARLY THIS MORNING. AT THE
SURFACE...HIGH PRESSURE IS LOCATED OVER THE CENTRAL CONUS...WITH
LOW PRESSURE DEVELOPING OVER THE NORTHERN ROCKIES. TEMPERATURES
ARE MILD THIS MORNING...MAINLY IN THE 60S. WINDS ARE GENERALLY OUT
OF THE SOUTH TO SOUTHEAST AT 5 TO 15 MPH.
FOR TODAY...OVERNIGHT CONVECTION WILL GRAZE FAR SOUTH CENTRAL
SOUTH DAKOTA DURING THE EARLY MORNING HOURS. BY THE AFTERNOON
INSTABILITY INCREASES GREATLY ACROSS WESTERN SOUTH DAKOTA WITH SOME
MODELS INDICATING CAPE VALUES EASILY OVER 3000 J/KG. SHEAR WILL
BE ADEQUATE TO SUPPORT SUPERCELLS...PARTICULARLY OVER THE ERN CWA.
STRONG STORMS COULD DEVELOP BY EARLY/MID AFTERNOON AS INITIAL WAVE
LIFTS THROUGH SWRLY FLOW. MAIN THREAT WITH THESE STORMS WILL BE
LARGE HAIL AND DAMAGING WINDS. CHANCES WILL CONTINUE INTO THE
EARLY EVENING WITH STORMS PUSHING TO THE EAST OF THE AREA BY LATE
EVENING.
ON TUESDAY...UPPER SHORTWAVE TROF WILL SWING THROUGH WESTERN NORTH
DAKOTA BY EARLY AFTERNOON...AS SURFACE TROF SLIDES THROUGH EASTERN
SOUTH DAKOTA. BEST CHANCE FOR PRECIP WILL BE CONFINED TO NORTH AND
WESTERN PORTIONS OF THE FORECAST AREA. REMAINDER OF THE AREA
SHOULD SEE PARTLY CLOUDY SKIES AND BREEZY WEST TO NORTHWEST WINDS
AS SURFACE TROF MOVES EAST OF THE AREA. HIGH TEMPS WILL BE IN THE
70S AND 80S.
&&
.LONG TERM...WEDNESDAY THROUGH SUNDAY
ISSUED AT 358 AM MDT MON JUN 24 2013
UPPER RIDGE BUILDING OVER THE WESTERN CONUS WILL BRING DRY AND
WARM WEATHER THROUGH THE END OF THE WORK WEEK. MODELS DIVERGE NEXT
WEEKEND AS TO THE STRENGTH OF THE RIDGE. ECMWF KEEPS THE RIDGE
AMPLIFIED OVER THE NRN ROCKIES/NRN PLAINS WHILE THE GFS SHOWS A
SLIGHT BREAKDOWN IN THE RIDGE WITH WESTERLIES DEVELOPING. WILL
FAVOR SLIGHT CHANCES FOR POPS OVER THE WEEKEND...WHILE KEEPING
TEMPS ABOVE AVERAGE.
&&
.AVIATION...FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON
ISSUED AT 1129 AM MDT MON JUN 24 2013
A STRONG UPPER LEVEL DISTURBANCE AND ASSOCIATED SFC
TROUGH WILL ADVECT THROUGH THE REGION TODAY...SUPPORTING TS
DEVELOPMENT THIS AFTERNOON/EVENING...POSSIBLY SEVERE. STRONG CAPPING
MAY LIMIT STORMS TO DISCRETE SUPERCELLS. HOWEVER...SOME HIRES MODEL
SOLUTIONS FAVOR THE DEVELOPMENT OF A SQUALL LINE ACROSS WESTERN
SD...PROPAGATING EAST THROUGH THE SD PLAINS THIS EVENING. WILL
RETAIN PREVIOUS VCTS MENTION AT GCC AND WILL ADD TEMPO ON A NEED
BE BASIS. DID ADD A TEMPO AT RAP WHERE BETTER CHANCES FOR TS WILL
BE FOUND. MVFR TO IFR CIGS/VIS WOULD BE POSSIBLE WITH ANY
THUNDERSTORM. COLD FRONT WILL PROPAGATE THROUGH THE AREA TUES
MORNING...WITH WINDS SHIFTING NW AND BECOMING BREEZY AT
TIMES...ESP OVER THE SD PLAINS.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
UPDATE...26
SHORT TERM...15
LONG TERM...JOHNSON
AVIATION...JC
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
327 PM EDT MON JUN 24 2013
.SYNOPSIS...
A TYPICAL SUMMER PATTERN CONTINUES WITH HIGH PRESSURE SITUATED
ACROSS THE SOUTHEAST AND SOUTHWEST FLOW KEEPING US WARM AND
HUMID WITH A DAILY THREAT OF SHOWERS AND STORMS THROUGH AT LEAST
MIDWEEK. A COLD FRONT WILL APPROACH THE REGION FROM THE NORTHWEST
LATE IN THE WEEK WITH MORE WIDESPREAD SHOWERS AND THUNDERSTORMS
LIKELY BY THURSDAY OR FRIDAY. THE FRONT LOOKS TO SLOW DOWN
CROSSING THE REGION OVER THE WEEKEND KEEPING SHOWERS AND STORMS
AROUND INTO AT LEAST SUNDAY.
&&
.NEAR TERM /THROUGH TUESDAY/...
AS OF 230 PM EDT MONDAY...
WIDELY SCATTERED CONVECTION LOOKS TO CONTINUE ACROSS THE AREA
INTO THIS EVENING WITH PERHAPS A GRADUAL MIGRATION OF STORM
DEVELOPMENT OFF INTO THE NE/EASTERN COUNTIES WHERE BETTER
HEATING/INSTAB EXISTS AND A WEAK VORT TAIL WILL BE PASSING
ACROSS. THIS SIMILAR TO THE LATEST HRRR AND RAP SOLUTIONS WHICH
END UP WITH MOST COVERAGE OVER THE EAST OR SE AS THE WEAK CAP
ALOFT LOOKS TO GIVE WAY BEFORE LOSS OF HEATING. THINK WESTERN
AREAS MAY ACTUALLY SEE LESS GIVEN CLOUDS AND LOWER CAPE DUE TO
EARLIER SHRA SO TRIMMING POPS BACK A BIT FAR WEST EARLY ON WHILE
GOING WITH CONTINUED SCATTERED COVERAGE EAST. AGAIN WITH LACK
OF MUCH UPPER SUPPORT...EXPECT COVERAGE TO BECOME MORE ISOLATED
THIS EVENING WITH SOME FOG DEVELOPING VALLEYS AND WHERE DOWNPOURS
OCCURRED EARLIER. SOME ADDED SHRA THEN POSSIBLE AGAIN LATER
TONIGHT AS THE WEAK UPSTREAM VORT OVER KY SLIDES EAST AND DAMPENS
OUT ACROSS THE MOUNTAINS BY MORNING. SINCE GUIDANCE NOT LATCHING
ONTO MUCH LIFT WITH THIS FEATURE...WILL ONLY KEEP A TOKEN POP IN
FAR WEST FOR NOW AND LEAVE ELSW DRY LATER ON.
LOWS A BIT MORE WARM/MUGGY OVERNIGHT WITH TEMPS ONLY DROPPING
INTO THE MID 60S TO AROUND 70 WITH LOW 60S ONLY IN THE DEEPEST
VALLEYS.
5H WEAKNESS SLOWS ACROSS THE REGION ON TUESDAY WITH LOW LEVEL
WESTERLY FLOW TURNING MORE SW DURING THE AFTERNOON AS THE EASTERN
LEE TROF SLIDES FARTHER EAST. FCST SOUNDINGS ARE EVEN MORE MOIST
THAN TODAY WITH LITTLE CAP ALTHOUGH QUESTIONS WITH THE DEGREE OF
ORGANIZATION UNDER SUCH WEAK FLOW ALOFT. THINK ENOUGH THETA-E
SUPPORT TO AT LEAST HAVE ANOTHER ROUND OF SCATTERED POPS BUT
WITH MORE MULTICELL CLUSTERS POSSIBLE ESPLY MOUNTAINS WHERE WILL
BE A BIT COOLER ALOFT. LOOKS LIKE WEAK DOWNSLOPE MAY CAUSE A
DELAY IN TSRA EAST WITH MORE OF A LATE AFTERNOON SCENARIO AIDED
BY WESTERN COVERAGE MOVING EAST AFTER SOME LOW LEVEL BACKING HAS
DEVELOPED. FOR NOW WILL CONTINUE TREND OF HIGH CHANCE POPS BUT MAY
NEED TO GO HIGHER LATER PENDING UPDATED MODEL SOLUTIONS.
WITH 85H TEMPS A COUPLE DEGREES WARMER AND LIGHT WEST
WINDS...WOULD EXPECT HIGHS TO TOP 90 SE...AND HEAD WELL INTO THE
80S OUTSIDE OF THE HIGHER ELEVATIONS...CLOSER TO THE WARMER MAV
MOS.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
AS OF 305 PM EDT MONDAY...
ZONAL FLOW AND A LEE TROUGH WILL START THE WEATHER PATTERN
TUESDAY NIGHT. THIS PATTERN WILL HAVE FADING DIURNAL
THUNDERSTORMS IN THE EVENING WITH PATCHY FOG DEVELOPING WHERE IT
RAINED DURING THE DAY TUESDAY. THE LEE TROUGH WILL HELP INITIATE
SCATTERED CONVECTION AGAIN WEDNESDAY AFTERNOON. PWATS ARE AROUND
NORMAL WITH MOISTURE ADVECTION COMING FROM THE SOUTHWEST. WITH
MOISTURE AND HEATING...A FEW STORMS COULD BE STRONG TO SEVERE
WEDNESDAY AFTERNOON AND EVENING. CORFIDI VECTORS ARE ALSO VERY
WEAK TUESDAY AND WEDNESDAY. STORMS WILL BE SLOW MOVING/ANCHORED
CREATING A VERY LOCALIZED FLASH FLOOD THREAT. ONCE AGAIN...SHOWERS
WILL FADE AFTER SUNSET WITH A FEW HANGING ON UNTIL MIDNIGHT WITH
LINGER INSTABILITIES.
TEMPERATURES WILL RUN WARMER THAN NORMAL THROUGH THE PERIOD BY 5
DEGREES OR SO. OVERNIGHT LOWS GENERALLY IN THE 60S WITH DAY TIME
HIGHS IN THE 80S...LOW 90S IN THE PIEDMONT.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 230 PM EDT MONDAY...
AN OCCLUDED LOW WILL WORKS ITS WAY TO THE EAST THURSDAY FROM THE
GREAT LAKES TO LAKE ERIE. WITH A LEE TROUGH IN THE EAST AND AN
APPROACHING WEAK FRONT/UPPER LEVEL TROUGH FROM THE WEST...MORE
AREAL COVERAGE OF CONVECTION IS EXPECTED THURSDAY AFTERNOON. HAIL
AND STRAIGHT LINE WINDS WILL BE THE PRIMARY THREAT. PWATS
INCREASE TO 2 STANDARD DEVIATION ABOVE NORMAL...MAKING FLASH
FLOOD A THREAT AS WELL.
THE FRONT AND LEE TROUGH BECOME ONE ON FRIDAY. CONVERGENCE IN
THIS SURFACE TROUGH SHOULD GENERATE STRONG CONVECTION...MAINLY
OVER THE PIEDMONT. NOT MUCH OF AN AIRMASS CHANGE AS THE FRONT
JOINS THE LEE TROUGH...THEREFORE CAN NOT RULE OUT THUNDERSTORMS
ACROSS THE MOUNTAINS AND FOOTHILLS FRIDAY.
A STRONGER FRONT IS EXPECTED TO APPROACH THE REGION ON SATURDAY.
THIS FRONT WILL BRING ANOTHER ROUND OF AREA-WIDE CHANCES OF
STRONG TO SEVERE THUNDERSTORMS. LOW CONFIDENCE ON FRONTAL TIMING
WITH A STRONG BLOCKING RIDGE IN THE WESTERN ATLANTIC THROUGH THE
PERIOD. EVEN IF THE FRONT TRACKS ACROSS THE AREA SATURDAY...RAIN
CHANCES WILL STILL EXIST SUNDAY AND MONDAY. THE BLOCKING RIDGE
COULD STALL THE FRONT INLAND OF THE EAST COAST...POSSIBLY
INTO THE PIEDMONT. WAVES WILL TRACK ALONG THE FRONT SUNDAY AND
MONDAY KEEPING THE CHANCE OF RAIN INTO EARLY NEXT WEEK.
TEMPERATURES WILL REMAIN WARMER THAN NORMAL INTO THE WEEKEND.
THE MORE AREAL COVERAGE OF SHOWERS DURING A GIVEN DAY WILL KEEP
TEMPERATURES CLOSER TO NORMAL.
&&
.AVIATION /19Z MONDAY THROUGH SATURDAY/...
AS OF 110 PM EDT MONDAY
SCATTERED SHRA/TSRA CLUSTERS HAVE DEVELOPED ACROSS THE MOUNTAINS
EARLY THIS AFTERNOON ALONG THE PERIPHERY OF THE EARLIER MID DECK.
EXPECT THIS COVERAGE TO SLOWLY INCREASE WHILE PUSHING SLOWLY EAST
UNTIL FADING OUT EARLY THIS EVENING. HOWEVER STILL LOW CONFIDENCE
IN WHETHER OR NOT ANY TAF LOCATION WILL EXPERIENCE A SHRA DIRECTLY
BUT ENOUGH OF A THREAT TO INCLUDE A VCTS MENTION AT MOST SPOTS
WITH A PERIOD OF PREVAILING MVFR VSBY AT KBLF THROUGH THE
AFTERNOON. ANY MORE ORGANIZED SHOWER OR STORM CLUSTER THAT DOES
COME IN THE VICINITY OF THE TAF LOCATIONS MAY RESULT IN A PERIOD
OF BRIEF IFR CIGS/VSBY WHICH WILL TEMPO AS NEEDED.
MOST OF THE DAYTIME ACTIVITY SHOULD DISSIPATE AFTER SUNSET.
HOWEVER...THERE MAY BE SOME LINGERING SHOWER ACTIVITY WEST OF THE
MTNS ASSOCIATED WITH A WEAK MID LEVEL WAVE THAT IS MOVING EAST
ACROSS KENTUCKY. THIS SHOWER ACTIVITY MAY REACH KBLF AFTER
MIDNIGHT TONIGHT...BUT WILL KEEP OUT OF THE TAF FCST ATTM UNTIL
CAN BE MORE CERTAIN OF TIMING GIVEN QUICK DISSIPATION OF SHRA OF
LATE WITH LOSS OF HEATING. OTRW APPEARS FOG WILL BE A BIT MORE
WIDESPREAD OVERNIGHT GIVEN HIGHER DEWPOINTS AND MORE RESIDUAL
MOISTURE FROM AFTERNOON CONVECTION. EXPECT A PERIOD OF MVFR AT
MOST SITES EXCLUDING KROA...AND PERHAPS KBLF WHILE KLWB/KBCB LOOK
TO DROP INTO IFR LEVELS WITH SOME LOW STRATUS AROUND LATE TONIGHT.
LOW CONDITIONS SHOULD IMPROVE BY MID MORNING TUE...FOLLOWED BY
MORE SCTD/BKN VFR CU AND DEVELOPING SHRA/TSRA AS A WEAK IMPULSE
ALOFT PUSHES ACROSS. WEST WIND MAY CAUSE LESS COVERAGE EARLY ON
WITH MORE ORGANIZED TSRA POSSIBLE BEYOND THE VALID TAF PERIOD
TUE AFTERNOON.
.AVIATION EXTENDED...
WE WILL BE TRANSITIONING FROM A FLAT UPPER RIDGE TO A BLOCKY PATTERN
WITH AN EASTERN CONUS TROF/WESTERN CONUS RIDGE THROUGH THE
EXTENDED PERIOD. SFC HIGH OFF THE EAST COAST WILL KEEP WARM AND
MOIST AIR OVER THE REGION WITH A SERIES OF WAVES RIPPLING THROUGH
THE FLOW. THIS WILL PRIMARILY LEAVE US WITH AN UNSTABLE AIRMASS IN
A WEAKLY FORCED CONVECTIVE ENVIRONMENT THROUGH MIDWEEK. EXPECT A
DIURNAL PATTERN OF CONVECTION WITH VFR IN THE MORNING...THEN MVFR
WITH SHRA/TSRA IN THE AFTERNOON AND EVE...THEN POSSIBLE IFR WITH
NOCTURNAL FOG/STRATUS. LOOKING LIKE LATTER PORTION OF THE WEEK
WILL BE MORE ACTIVE. AS THE PATTERN FINALLY BECOMES MORE AMPLIFIED
AND THE ERN TROF SINKS DOWN INTO THE REGION...IT SHOULD PUSH A
COLD FRONT THROUGH TOWARD THE END OF THE WEEK...WITH BETTER
AVIATION CONDITIONS THEREAFTER. EXPECT WINDS TO REMAIN ON THE
LIGHT SIDE UNTIL THURSDAY WHEN LOW LEVEL WIND FIELD BEGINS TO
INCREASE AHEAD OF APPROACHING COLD FRONT. BEST COVERAGE OF STORMS
LOOKS TO BE ON THURSDAY AS WELL WITH A POSSIBLE LINE AHEAD OF THE
FRONT THRUSDAY AFTERNOON/EVENING.
&&
.EQUIPMENT...
AS OF 1225 PM EDT SUNDAY...
DANVILLE ASOS VISIBILITY SENSOR REMAINS INOP AND EXPECTED TO BE
FIXED TUESDAY OR WEDNESDAY OF THIS WEEK.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH/WP
NEAR TERM...JH
SHORT TERM...RCS
LONG TERM...RCS
AVIATION...JH/PM
EQUIPMENT...WP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
405 PM CDT MON JUN 24 2013
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 304 PM CDT MON JUN 24 2013
AT 3 PM...A SQUALL LINE WAS MOVING EAST THROUGH EAST-CENTRAL
AND SOUTHEAST IOWA. THIS LINE HAS WIPED OUT MUCH OF THE
INSTABILITY THAT MANY OF 24.00Z AND 24.06Z MODELS WERE FORECASTING
TO MOVE INTO NORTHEAST IOWA...SOUTHEAST MINNESOTA...AND SOUTHWEST
AND CENTRAL WISCONSIN TONIGHT. EVEN SOME OF THE 24.12Z
DETERMINISTIC MODELS WERE NOT HANDLING THIS LINE WELL...SO THEY ARE
TOO HIGH ON THEIR CAPES ACROSS IOWA. IN ADDITION...THIS LINE ALSO
DISRUPTED THE 925 MB AND 850 MB MOISTURE TRANSPORT INTO THE
REGION. AS A RESULT...THE HEAVY RAIN THREAT FOR THIS EVENING LOOKS
MUCH LESS THAN WHAT IT WAS LOOKING LIKE EARLIER THIS MORNING.
FOR OVERNIGHT...THERE IS A LOT OF UNCERTAINTY ON HOW THIS PERIOD
IS GOING TO MATERIALIZE. THE 24.12Z NAM WHICH HAD A SLIGHTLY
BETTER HANDLE ON THE SQUALL LINE PUSHED AN OUTFLOW BOUNDARY SOUTH
TO THE MISSOURI AND IOWA BORDER...THUS ITS BEST MOISTURE
TRANSPORT IS FOCUSED MUCH FURTHER SOUTH. THE 925 MB MOISTURE
TRANSPORT HAS SHIFTED TOWARD SOUTHERN IOWA. IF THIS VERIFIES...
MUCH OF THE PRECIPITATION WOULD REMAIN SOUTH OF THE AREA FOR THIS
TIME PERIOD. EVEN THE LATEST RAP IS LEANING TOWARD THIS SCENARIO
TOO. MEANWHILE BOTH THE ECMWF AND GEM MODELS SUGGEST THAT AS THE
SHORT WAVE IN THE SOUTHERN PLAINS MOVES NORTHEAST INTO THE
SOUTHERN PLAINS...THE 850 MB MOISTURE TRANSPORT SHIFTS BACK
NORTHWARD TOWARD THE AREA TOWARD SUNRISE. IF THIS SCENARIO
VERIFIES...THERE COULD BE A POTENTIAL FOR THE REDEVELOPMENT OF
SHOWERS AND THUNDERSTORMS LATE TONIGHT. WITH ITS PRECIPTABLE WATER
VALUE CLOSE TO 2.00 INCHES AND WARM CLOUD LAYER DEPTHS UP TO
4.5 KM...THERE WOULD BE THE POTENTIAL FOR HEAVY RAIN. WITH SO MANY
DIVERSE MODEL SOLUTIONS...OPTED TO LOWER THE PRECIPITATION CHANCES
SOME AND ALSO SHIFTED THE HIGHER CHANCES TO LATER IN THE NIGHT.
HOPEFULLY...THE 24.00Z MODELS WILL BE BETTER AT RESOLVING THE
STABLE LAYER THAT WAS LEFT IN THE WAKE OF THE SQUALL LINE.
ON TUESDAY...EXPECT THE 925 MB AND 850 MB MOISTURE TRANSPORT TO
INCREASE ACROSS IOWA. HOWEVER THERE IS SOME UNCERTAINTY HOW FAR
NORTH THIS OCCUR. THE 24.18Z NAM AND 24.12Z GFS WOULD SUGGEST
THAT THE HEAVIEST RAIN WOULD FALL ACROSS CENTRAL IOWA. MEANWHILE
THE 24.12Z ECMWF AND GEM WOULD SUGGEST THAT THE HEAVIEST RAIN WOULD
FALL SOUTH OF INTERSTATE 90. WITH THE INITIAL CONDITIONS SO
MUDDLED...CONFIDENCE IS NOT THAT HIGH.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 304 PM CDT MON JUN 24 2013
ON TUESDAY NIGHT...MUCH OF THIS TIME PERIOD REMAINS UNCLEAR DUE
TO UNCERTAINTIES ON WHERE THE BOUNDARIES WILL END UP FROM TONIGHT
AND WHERE THUNDERSTORMS DEVELOP ON TUESDAY. THE GEM AND ECMWF
HAVE THEIR MESOSCALE CONVECTIVE COMPLEXES MOVING ALONG AND SOUTH
OF THE INTERSTATE 94 CORRIDOR. MEANWHILE THE GFS AND NAM SUGGEST
THAT THE MESOSCALE CONVECTIVE COMPLEX WILL DEVELOP ACROSS
IOWA...AND THEN MOVES IT NORTHEAST WITH THE SHORT WAVE INTO THE
FORECAST AREA. WITH WARM CLOUD LAYER DEPTHS OVER 4 KM AND
PRECIPITABLE WATER VALUES AROUND 2 INCHES. THERE WILL BE THE
POTENTIAL FOR SOME FLASH FLOODING.
ON WEDNESDAY AND WEDNESDAY EVENING...ADDITIONAL SHOWERS AND
THUNDERSTORMS WILL BE POSSIBLE ACROSS THE AREA AS THE LOW PRESSURE
AREA MOVES EAST ACROSS THE AREA. PRECIPITABLE WATER VALUES SLOWLY
DROP TO AROUND 1.60 INCHES AND THE WARM CLOUD LAYER DEPTHS FALL
INTO THE 3 TO 3.5 KM RANGE. WHILE THERE WILL BE THE POTENTIAL FOR
SOME HEAVY RAIN...THE AMOUNTS LOOK TO BE MUCH LESS THAN WHAT THEY
ARE FROM TONIGHT INTO TUESDAY NIGHT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 129 PM CDT MON JUN 24 2013
PERIODS OF TSRA WILL OCCUR THROUGH ABOUT 00Z. THIS MAY NEED TO BE
EXTENDED IN THE TAF SITES...WILL MONITOR...AS 18Z TAFS HAVE 2
HOURS OF TEMPO TSRA.
MASSIVE CONVECTIVE COMPLEX ACROSS IA HAS REALLY IMPACTED TSRA
FORECAST FOR THE OVERNIGHT HOURS. WAS THINKING THAT A MASSIVE RAIN
EVENT WAS IN PLACE BUT WITH THE IA CONVECTION...MANY OF THE GOOD
SET UP PARAMETERS ARE NOT AS FAVORABLE ANY LONGER OVERNIGHT. LATER
FORECASTS MAY REMOVE THE TSRA TO LESSER HOURS OR IMPACT. CEILINGS
WILL ALSO BE VERY DIFFICULT WITH MESSY...UNORGANIZED PATTERN
THROUGH THE PERIOD.
CONFIDENCE IS LOW IN THE TAF BEYOND 4-5 HOURS.
&&
.HYDROLOGY...
ISSUED AT 304 PM CDT MON JUN 24 2013
WITH A WIDE VARIETY OF SOLUTIONS IN THE 24.12Z AND 24.18Z
MODELS...CONFIDENCE HAS LOWERED ON THE THREAT FOR FLASH FLOODING
TONIGHT. HOWEVER WITH MANY RIVERS REMAINING EITHER HIGH OR ARE
FLOODING ACROSS NORTHEAST IOWA AND SOUTHWEST WISCONSIN. CONFIDENCE
WAS NOT HIGH ENOUGH TO CANCEL THE FLASH FLOOD WATCH.
LOOKING AHEAD TO TUESDAY AND TUESDAY NIGHT...SOME MODELS SUGGEST
THAT HEAVY RAIN COULD FALL SOUTH OF INTERSTATE 94. MEANWHILE OTHER
MODELS HINT THAT THE HEAVIEST PRECIPITATION WILL REMAIN SOUTH OF
THE FORECAST AREA. WITH SUCH DIVERSE SPREADS IN THE MODELS...OPTED
NOT TO EXTEND THE FLASH FLOOD WATCH INTO TUESDAY NIGHT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR WIZ032>034-041>044-
053>055-061.
MN...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR MNZ079-086>088-
094>096.
IA...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR IAZ008>011-018-019-
029-030.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...BAUMGARDT
HYDROLOGY...BOYNE
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
334 PM CDT MON JUN 24 2013
.VERY SHORT TERM...TONIGHT AND TUESDAY.
TONIGHT - CONFIDENCE...LOW
EXPECTING A WEAKENED VERSION OF IOWA COMPLEX TO TRAVERSE ACROSS
THE CWA LATER THIS AFTERNOON AND EARLY EVENING. STRONGEST PORTION
OF IOWA COMPLEX WILL LIKELY RIDE THE MLCAPE GRADIENT IN NORTHERN
IL PER SPC MESO ANALYSIS...BUT SOME INCREASE INSTABILITY SNEAKING
BACK NORTH TOWARDS THE SRN COUNTIES. IN FACT 3 HOURLY MLCAPE
CHANGE WHILE GREATEST IN NRN IL...DOES SHOW AN AXIS INTO THE FAR
SOUTH. THIS CLOSE ENOUGH CALL IN THE SOUTHERN TIER OF COUNTIES FOR
THE SVR WATCH FROM SPC. LIKE LAST NIGHT THE MAIN CHALLENGE IS THE
DEGREE AND LOCATION OF REDEVELOPMENT BECOMES THE KEY QUESTION.
GETTING MODEL SOLUTIONS ALL OVER THE MAP FROM HEAVY RAINS...TO
SCATTERED DEVELOPMENT TO NEXT TO NOTHING. MODELS CONSENSUS OF 850
MILLIBAR JET CORE LOOKS VERY SIMILAR TO WHERE WE NOTICED IT SUNDAY
PROGGD FOR 12Z THIS MORNING. AND GIVEN WHERE ONGOING CONVECTION IS
LAYING ITSELF OUT HAVE SOME CONCERN THAT IT MAY BE ANOTHER
GLANCING SHOT ONCE AGAIN. HRRR DOES SHOW SOME ELEVATED DEVELOPMENT
LATER TONIGHT. SO CERTAINLY WORTHY OF KEEPING THE WATCH GOING FOR
NOW.
TUESDAY - CONFIDENCE...MEDIUM
AXIS OF LOW LEVEL JET TRANSLATES EAST A BIT AND IS AIMED MORE
TOWARDS SOUTHERN WI. 500 MILLIBAR SHOWS PERIODIC VORTICITY MAXIMA
WAVERING THROUGH THE WEAK WESTERLY FLOW. SOME UPPER DIVERGENCE NOTED
AS WELL...THOUGH OVERALL JET ACTION LOOKS PRETTY WEAK. CWASP NUMBERS
IN THE 60S...A FEW LOW 70S OFF THE NAM. BUT NOTHING EXTREME. WILL
KEEP HIGH END CHANCE/LIKELY POPS GOING WITH THE OVERALL PATTERN
STILL FAVORING CONVECTION DUE INSTABILITY AND RIPPLES IN THE FLOW.
.SHORT TERM...TUESDAY NIGHT THROUGH THURSDAY.
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...FORECAST CONFIDENCE LOW TO
MEDIUM.
EVOLUTION FROM MOIST AND UNSTABLE NEAR-ZONAL WSW FLOW TO COOLER AND
DRIER NW FLOW BEGINS WITH APPROACH OF SHORT WAVE TROUGH AND
ASSOCIATED SURFACE LOW FROM THE DAKOTAS TUESDAY NIGHT...AND THEN
PASSAGE OF THE TROUGH AND LOW THROUGH THE WESTERN GREAT LAKES
WEDNESDAY AND WEDNESDAY NIGHT.
BETTER FORCING FROM THERMAL ADVECTION PER NAM/GFS 850-700MB Q-VECTOR
CONVERGENCE MAXIMA FOLLOWS A FAMILIAR PATTERN OF LATE ACROSS
NRN/CENTRAL IA INTO NRN IL...JUST BRUSHING SRN WI...WHICH FOLLOWS
ALONG THE NOSE OF THE THERMAL RIDGE AND STRONGEST 850 MB WINDS AS
THEY VEER FROM SOUTH TO SOUTHEAST WITH WAVE PASSAGE. HOWEVER
CONFIDENT FOR LIKELY POPS EVERYWHERE IN CWA WITH LARGE SALE FORCING
FOR ASCENT PROVIDED BY DIFFERENTIAL CVA THAT WORKS ON UNSTABLE AIR
MASS...WITH LOW LEVEL FORCING PROVIDED BY LOW TO MID-LAYER
FRONTOGENETIC FORCING.
FLOODING A CONCERN WITH ANY CONVECTION IN THIS MOISTURE RICH
ENVIRONMENT WITH 1.7 TO 1.9 INCH PW/S OR ABOUT 160 PCT OF NORMAL.
BEST PERFORMING MODEL QPF FORECASTS BRING AREAL AVERAGE
PRECIPITATION OF 1 TO 1.5 INCHES TO THE CWA...BUT ACTUAL AMOUNTS
WILL BE MUCH HIGHER WITH ANY MCS THAT MOVES ACROSS CWA.
KEPT LIKELY POPS IN THE NORTH WITH BETTER OMEGA AS SFC LOW MOVES
THROUGH WEDNESDAY...AND CHANCE POPS EVERYWHERE ELSE...TAPERING OFF
WEDNESDAY NIGHT FROM WEST TO EAST BEHIND THE LOW.
WITH EXPECTED CONVECTION AND AT LEAST A SIGNIFICANT AMOUNT OF CLOUD
DEBRIS WENT WITH BLENDED HIGHS THAT TEND TOWARD THE COOLER SIDE OF
GUIDANCE.
THURSDAY...FORECAST CONFIDENCE MEDIUM.
MODELS DIFFER WITH HOW FAR EAST TO TAKE INITIAL SHORT WAVE TROUGH BY
THURSDAY MORNING...BUT ALL SHOW VORTICITY MAXIMA DROPPING THROUGH
EASTERN WI AT SOME POINT DURING THE DAY THURSDAY. NAM SOUNDINGS LOOK
A BIT TOO GENEROUS WITH SURFACE DEW POINTS...BUT LOW TO MID 80 TEMPS
WITH MID-UPPER 60 DEW POINTS STILL YIELD TALL SKINNY SURFACE-BASED
CAPE OF AT LEAST 600-800 J/KG...SO WILL HAVE CHANCE THUNDER IN THE
EAST...BUT LEAVE WESTERN AREAS DRY.
.LONG TERM...THURSDAY NIGHT THROUGH MONDAY. FORECAST CONFIDENCE
MEDIUM.
MODELS CONTINUE TO DIG EASTERN TROUGH THROUGH THE END OF THE WORK
WEEK AND DROP A A REINFORCING SHORT WAVE THROUGH THE REGION THAT
AIDS IN CLOSING OFF A 500 MB LOW SOMEWHERE OVER THE CENTRAL/EASTERN
GREAT LAKES SATURDAY. INSTABILITY WITH THE 500 COLD POOL OVER THE
REGION AND VORT MAXES ROTATING THROUGH THE TROUGH WILL KEEP AT LEAST
SLIGHT CHANCE POPS IN THROUGH THE EXTENDED...WITH AT OR SLIGHTLY
BELOW NORMAL TEMPERATURES INTO NEXT WEEK.
&&
.AVIATION/00Z TAFS/...CONVECTION ACROSS IOWA TO HAVE GREATEST IMPACT
IN FAR SRN WI INTO EARLY EVENING. STRONGEST ACTIVITY LOOKING TO STAY
SOUTH OF THE BORDER. THEN SETUP LOOKS SIMILAR TO LAST NIGHT WHERE
REDEVELOPMENT BECOMES FOCUSED FURTHER SOUTH. MODEL SOLUTIONS ARE
QUITE DIVERGENT ON HOW THE LATE NIGHT CONVECTION PLAYS OUT. BUT IF
LAST NIGHT IS ANY INDICATION...SOME TSRA POSSIBLE LATER TONIGHT INTO
THE EARLY MORNING HOURS...THEN MORE REDEVELOPMENT DURG TUE AFTN/EVE.
OVERALL...VFR WITH POCKETS OF MVFR/ISOLATED IFR IN ANY OF THE
HEAVIER STORMS.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR WIZ046-047-056-057-
062-063-067>069.
LM...NONE.
&&
$$
TONIGHT/TUESDAY AND AVIATION/MARINE...COLLAR
TUESDAY NIGHT THROUGH MONDAY...REM
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND TUESDAY
ISSUED AT 226 PM CDT MON JUN 24 2013
THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A
SHORTWAVE TROUGH MOVING ENE OVER FAR EASTERN SOUTH DAKOTA AND INTO
SOUTHWEST MINNESOTA. AREA OF CONVECTION AHEAD OF THIS TROUGH IS
DRAWING CLOSER TO THE SW WISCONSIN BORDER. CLOUD COVER OVER CENTRAL
AND EAST-CENTRAL WISCONSIN HAS LIMITED HEATING SOMEWHAT TODAY...BUT
ML CAPES ARE APPROACHED A 1K J/KG...THOUGH STILL HAVE SOME CIN TO
OVERCOME. NOT SURE IF THIS INHIBITION WILL GET OVERCOME...SINCE
CLOUDS WILL ONLY THICKEN FROM HERE ON OUT. MOSTLY CLEAR SKIES EXIST
BEHIND THIS SHORTWAVE OVER THE CENTRAL PLAINS...AND THE NEXT
SHORTWAVE IS MOVING OVER THE CENTRAL ROCKIES. MAIN FORECAST
CONCERNS INCLUDE PRECIP CHANCES TONIGHT...AND SEVERE WEATHER CHANCES
TOMORROW.
TONIGHT...THE SHORTWAVE TROUGH MOVING INTO FAR SOUTHWEST MINNESOTA
WILL CONTINUE TO TRACK ENE ACROSS SOUTHERN MINNESOTA AND THE
NORTHERN HALF OF WISCONSIN THIS EVENING. CURRENT TRAJECTORY OF
PRECIPITATION WILL PLACE THE BEST CHANCES SOUTH OF A TOMAHAWK TO
IRON MOUNTAIN LINE. WITH CLOUD COVER KEEPING TEMPERATURES IN THE
UPPER 70S TO LOWER 80S OVER CENTRAL AND EAST-CENTRAL WISCONSIN...THE
STORMS WILL HAVE SOME CIN TO OVERCOME DESPITE ML CAPES AROUND 1000
J/KG. THINKING SEVERE CHANCES IS RATHER REMOTE SINCE THE NORTHERN
END OF THE THUNDERSTORM COMPLEX IS MOSTLY STRATIFORM. PWATS WILL BE
INCREASING OVER 1.50 INCHES SO THINKING HEAVY RAINFALL WILL BE THE
MAIN THREAT WITH THESE STORMS...BUT EVEN THAT DOES LOOK THAT
POSSIBLE. SHOWERS AND STORMS WILL HAVE MOSTLY EXITED THE REGION BY
LATE IN THE EVENING...AND THEY SHOULD LAY OUT AN OUTFLOW BOUNDARY
OVER SOUTHERN WISCONSIN OR POINTS FURTHER SOUTH. RETURN FLOW WILL
REDEVELOP OVER THE NORTHERN PLAINS LATE SO THINKING ANY CONVECTION
LATE TONIGHT WILL FALL ALONG THIS OUTFLOW BOUNDARY. HAVE DROPPED
POPS SIGNIFICANTLY AFTER MIDNIGHT AND ACROSS NORTHERN WISCONSIN.
MUGGY LOWS IN THE MIDDLE 60S.
TUESDAY...MUCH OF THE DETAILS IN TOMORROWS WEATHER WILL REVOLVE
AROUND WHERE RESULTING OUTFLOW BOUNDARIES END UP AND HOW QUICKLY THE
ATMOSPHERE CAN RECOVER. IF THE LAST FEW DAYS ARE ANY
INDICATION...IT COULD TAKE UNTIL MID TO LATE AFTERNOON FOR
DESTABILIZATION TO OCCUR. BY THIS TIME...RETURN FLOW WILL BE
SPREADING NORTHEAST INTO THE REGION AS A SHORTWAVE CURRENTLY OVER
COLORADO LIFTS INTO THE NORTHERN MISSISSIPPI VALLEY. DO NOT TRUST
MODEL SOUNDINGS MUCH...BUT TEMPS IN THE LOW TO MID 80S AND DEWPOINTS
IN THE UPPER 60S SHOULD YIELD AT LEAST 1000 J/KG OF CAPE. 0-6KM
BULK SHEAR IS RATHER POOR AROUND 20 KTS...SO WILL BE TOUGH TO GET
ANY ORGANIZED CONVECTION. BUT CANNOT RULE OUT AN ISOLATED MENTION
IF THE INSTABILITY RECOVERS. HIGHS IN THE LOW TO MID 80S.
.LONG TERM...TUESDAY NIGHT THROUGH MONDAY
ISSUED AT 226 PM CDT MON JUN 24 2013
BRIEF PERIOD OF ZONAL FLOW WILL BE ACCOMPANIED BY PRIMARY
SHORTWAVE FORECAST TO TRAVERSE THE WESTERN GREAT LAKES DURING THE
MIDDLE OF THE WORK WEEK. THERAFTER...THE MEDIUM RANGE GUIDANCE
CONTINUES TO ADVERTIZE PRONOUNCED RIDGING OVER THE WESTERN CONUS
WITH DEEPENING DOWNSTREAM TROUGH ACROSS THE GREAT LAKES AND OHIO
VALLEY. LOTS OF UNCERTAINTY WITH RESPECT TO THE DETAILS OF
EMBEDDED DISTURBANCES WITHIN THE INCREASING NORTHWESTERLY FLOW
OVER THE STATE LATE IN THE WORK WEEK. DAILY AVERAGE TEMPERATURES
SHOULD REMAIN ABOVE NORMAL...THEN FALL OFF CLOSER TO NORMAL OR
PERHAPS A LITTLE BELOW NORMAL BY THE WEEKEND.
TUESDAY NIGHT AND WEDNESDAY...
PRIMARY FORECAST CHALLENGE EARLY IN THE EXTENDED WILL BE TRYING
TO NARROW DOWN THE TIMING AND LOCATION OF CONVECTIVE ACTIVITY
ASSOCIATED WITH THE PRIMARY SHORTWAVE DISTURBANCE TUESDAY NIGHT
AND WEDNESDAY. FORECAST CONFIDENCE FOR THIS PERIOD IS LOW.
NOT GOING TO BUCK TRENDS PAST FEW DAYS AND WILL BET AGAINST
QUASISTATIONARY FRONTAL BOUNDARY NEAR THE ILLINOIS-WISCONSIN
MAKING MUCH NORTHWARD PROGRESS INTO THE FORECAST AREA TUESDAY
NIGHT DESPITE RATHER ROBUST SOUTHWESTERLY LOW-LEVEL FLOW AHEAD OF
THE APPROACHING SHORTWAVE. LATEST MODEL TRENDS SEEM TO SUGGEST
THAT BULK OF DEEP CONVECTION WILL FIRE ALONG BOUNDARY TO OUR
SOUTHWEST AROUND 00Z WEDNESDAY THEN HEAD MORE EASTERLY MAINLY
ACROSS THE SOUTHERN THIRD OF THE STATE TUESDAY NIGHT...AS LLJ
VEERS WSW BY 12Z WEDNESDAY. WILL TWEAK POPS SOMEWHAT TUESDAY
PLACING HIGHEST PROBABALITIES ACROSS THE SOUTHERN THIRD OF THE
FORECAST AREA AND TAPERING TO CHANCE ACROSS THE FAR NORTHEAST. IF
THIS SCENARIO PLAYS OUT...FEEL BEST COMBINATION OF SHEAR AND
INSTABLITY SUPPORTAIVE OF SEVERE STORMS WILL ALSO BE FOCUSED
GENERALLY SOUTH OF HIGHWAY 29 TUESDAY NIGHT. PW VALUES FORECAST
TO REMAIN QUITE HIGH...NEARLY 2SD ABOVE NORMAL TUESDAY
NIGHT...THUS LOCALLY HEAVY RAINFALL IS ALSO THREAT. AS SHORTWAVE
TROUGH AND ASSOCIATED SURFACE LOW MOVE ACROSS THE FORECAQST AREA
WEDNESDAY EXPECT MORE WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY
OVER THE ENTIRE FORECAST AREA. AT THIS TIME APPEARS WILL BE
CONSIDERABLE CLOUDS AROUND DURING THE DAY ON WEDNESDAY THUS FEEL
SEVERE THREAT WILL BE MARGINAL. AGAIN SOME POTENTIAL FOR LOCALLY
HEAVY RAINFALL ESPECIALLY OVER THE FOX VALLEY. WILL TREND MAX
TEMPS A FEW DEGREES LOWER WEDNESDAY ASSUMING MORE WIDESPREAD
PRECIPITATION AND CLOUD COVER. /EB/
THURSDAY INTO THE WEEKEND...
LONG RANGE MODELS IN AGREEMENT ON DEVELOPMENT OF HUGE UPPER RIDGE
OVER 110 W LATITUDE AND TROF OVER GREAT LAKES. THIS SPELLS A
SHOWERY PERIOD WITH TEMPS AOB NORMAL ACROSS REGION FRIDAY INTO
MONDAY. BOTH ECMWF AND GFS SHOW SIGNS OF ADDITIONAL ENERGY
DIGGING INTO TROF NEXT WEEK...KEEPING THE COOLISH WEATHER AROUND.
/JKL/.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1228 PM CDT MON JUN 24 2013
A THUNDERSTORM COMPLEX OVER SOUTHERN MINNESOTA AND IOWA IS EXPECTED
TO MOVE NORTHEAST THIS AFTERNOON INTO WISCONSIN. CURRENT TRENDS
SUPPORT CENTRAL AND NORTHEAST WISCONSIN RECEIVING SHOWERS AND
THUNDERSTORMS FROM THIS COMPLEX LATE THIS AFTERNOON AND INTO THE
EVENING. CIGS/VSBYS WILL LIKELY FALL INTO THE MVFR RANGE WITHIN ANY
THUNDERSTORMS. FOLLOWING THE PASSAGE OF THESE STORMS...WILL LIKELY
SEE A BREAK BUT UNCERTAINTY WILL BE HIGH AS TO HOW LONG. ITS QUITE
POSSIBLE THAT THE BREAK COULD LAST UNTIL TOMORROW AFTERNOON BEFORE
THE NEXT AROUND OF SHOWERS AND STORMS ARRIVE.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......JKL
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
131 PM CDT MON JUN 24 2013
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 129 PM CDT MON JUN 24 2013
THIS IS A TOUGH ONE. CONFIDENCE WAS HIGHER THIS MORNING THAT A
SIGNIFICANT FLOODING SET UP WAS IN PLACE TONIGHT. HOWEVER...THE
MASSIVE AMOUNT OF CONVECTION OVER IOWA AND INTO NRN MO IS CRASHING
CONFIDENCE LEVELS. IT APPEARS THE OVERNIGHT COULD BE ALMOST DRY.
THE IDEAL SIGNIFICANT FLOODING SCENARIO IS IOWA BEING PRETTY CLEAN
AT THIS POINT AND BUILDING INSTABILITY...VERY HIGH INSTABILITY.
THEN...THE LOW-LEVEL JET BECOMING ACTIVE AND CONVERGENT ACROSS
MOST OF SRN MN...WITH INDIVIDUAL STORMS TRACKING EAST. THIS HAD
BEEN THE SIGNAL IN THE MODEL GUIDANCE SINCE YESTERDAY...BUT THIS
IS NOT GOING TO VERIFY WITH THE CURRENT WIDESPREAD CONVECTION
FOULING IT UP. THE WARM FRONT AND ISENTROPIC SLOPE IS BEING PUSHED
FURTHER SOUTH /GUESS IT IS A COLD FRONT THEN/. THIS IS ACTUALLY
GOOD NEWS AS WE WERE PRETTY WORRIED ABOUT A LONG AXIS FROM KFSD-
KLSE OF PROLONGED LOW-LEVEL JET UP SLOPE AND CONVERGENCE OF AN
UNSTABLE AIR MASS...AND DEEP WARM CLOUD REPEATING THUNDERSTORMS.
IN FACT...THE MOST RECENT TWO RAP RUNS OF 16-17Z BOTH HAVE
MIGRATED TOWARD THIS DRIER SCENARIO AND EVEN HAVE WESTERLY 850 MB
FLOW OVERNIGHT.
SO...WE ARE BEGINNING TO BELIEVE A MORE LIKELY OUTCOME MAY BE
CONVECTION MOVING THROUGH THIS AFTERNOON AND EARLY EVENING...AND
A RECOVERY PERIOD NEEDED BEFORE MORE WEATHER OCCURS. INSTABILITY
SHIFTING NORTH INTO THE KFSD AREA LATE OVERNIGHT INITIATING
CONVECTION IN NORTHWEST IA TUESDAY...SHIFTING EAST. BUT...IT COULD
MEAN NO HIGHER END RAINFALL NUMBERS WE UPGRADED TO THIS
MORNING...AND LESSER IMPACT FOR SURE. WE ARE TAKING A CAUTIOUS
APPROACH ON THIS...BUT IT APPEARS LESS THREAT MAY BE PRESENTING
ITSELF.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 415 AM CDT MON JUN 24 2013
FOR TUE NIGHT THRU WED NIGHT MODELS SHOW THE REMNANTS OF THE
TROUGHING NOW OVER CA WILL LIFT INTO AND ACROSS THE UPPER MIDWEST.
TREND CONTINUES TO FAVOR STRONGER OF THE EARLIER RUNS. WITH THIS
BEING A LARGER SCALE FEATURE AND THE DECENT MODEL CONSISTENCY FCST
CONFIDENCE FOR THIS PERIOD IS AVERAGE.
AS THE STRONGER MID LEVEL TROUGH MOVES INTO THE UPPER MIDWEST TUE
NIGHT THE PLAINS SFC LOW MOVES INTO MN/WI. LOWER LEVEL THERMO
DYNAMIC FORCING/LIFT AND MOISTURE TRANSPORT REMAINS STRONG INTO THE
AREA AHEAD OF THESE FEATURES. WHERE THE FRONT AHEAD OF THE LOW FROM
TODAY/TUE ENDS UP WILL DETERMINE WHERE THE STRONGER LIFT WILL BE.
MODEL CONSENSUS HAS IT SOMEWHERE OVER THE FCST AREA TUE NIGHT...
THUS CARRIED HIGHEST SHRA/TSRA CHANCES IN THE 60-70 PERCENT RANGE
OVER THE NORTHEAST 2/3 OF THE FCST AREA. PW VALUES REMAIN IN THE 1.5
TO 1.75 INCH RANGE WITH ANY STORMS CAPABLE OF PRODUCING HEAVY RAINS.
AGAIN...WILL LIKELY NEED MORE FLASH FLOOD WATCHES FOR PORTIONS OF
THE AREA INTO TUE NIGHT WITH POTENTIAL FOR ANOTHER 0.5 TO 1.5
INCHES...LOCALLY MORE...OF RAIN.
ONCE THIS STRONGER MID LEVEL TROUGH PASSES TUE NIGHT/WED MORNING THE
FLOW PATTERN OVER NOAM BEGINS TO CHANGE WITH RIDGING BUILDING OVER
THE WESTERN CONUS AND INCREASING NORTHWEST FLOW ALOFT OVER THE
UPPER MIDWEST. DRIER AIR AND HIGH PRESSURE WILL SLOWLY SPREAD INTO
MN/IA/WI WED/WED NIGHT. SHRA/TSRA CHANCES WILL LINGER WED WITH THE
SFC LOW-MID LEVEL TROUGH OVER THE REGION. SHRA/TSRA CHANCES
DECREASE WED NIGHT AS HGTS RISE AND THE SFC-MID LEVEL LOW/TROUGH
MOVE EAST OF THE AREA.
DUE TO THE CONVECTION DETAIL UNCERTAINTIES...CONTINUED TO USE THE
MODEL/ENSEMBLE CONSENSUS FOR LOWS/HIGHS IN THE TUE NIGHT TO WED
NIGHT PERIOD.
ONCE AGAIN NOT A LOT OF TIME SPENT LOOKING AT THE DAY 4-7 PERIOD.
24.00Z MEDIUM RANGE MODELS MAINTAIN A GOOD CONSENSUS FOR THE
BUILDING WESTERN NOAM RIDGING AND EASTERN NOAM TROUGHING IN THE THU-
SUN PERIOD...WHICH PUTS THE REGION UNDER INCREASING NORTHWEST FLOW
ALOFT. THU-SUN SHAPING UP TO BE A DRIER PERIOD WITH TEMPERATURES
COOLING TO NEAR OR A BIT BELOW NORMAL. FCST CONFIDENCE FOR THIS
PERIOD LOOKS TO BE AVERAGE TO GOOD.
DRIER HIGH PRESSURE BUILDS IN FOR THU-SUN...BUT PLENTY OF RESIDUAL
LOW LEVEL MOISTURE AND MAXIMUM EVAPO-TRANSPIRATION FROM WELL WATERED
VEGETATION AND WET SOILS APPEAR TO REMAIN...ALONG WITH STEEP LOW/
MID LEVEL LAPSE RATES AND SHORTWAVES RIPPLING THRU THE NORTHWEST
FLOW ALOFT. THU-SUN TRENDING TO BE DRY DAYS BUT SOME SMALLER
MAINLY DIURNAL SHRA/TSRA CHANCES TO PERSIST...AIDED BY THE PASSING
SHORTWAVES FROM TIME TO TIME. MODEL/ENSEMBLE CONSENSUS FOR HIGHS/
LOWS IN THE DAY 4-7 PERIOD LOOK WELL TRENDED FOR NOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 129 PM CDT MON JUN 24 2013
PERIODS OF TSRA WILL OCCUR THROUGH ABOUT 00Z. THIS MAY NEED TO BE
EXTENDED IN THE TAF SITES...WILL MONITOR...AS 18Z TAFS HAVE 2
HOURS OF TEMPO TSRA.
MASSIVE CONVECTIVE COMPLEX ACROSS IA HAS REALLY IMPACTED TSRA
FORECAST FOR THE OVERNIGHT HOURS. WAS THINKING THAT A MASSIVE RAIN
EVENT WAS IN PLACE BUT WITH THE IA CONVECTION...MANY OF THE GOOD
SET UP PARAMETERS ARE NOT AS FAVORABLE ANY LONGER OVERNIGHT. LATER
FORECASTS MAY REMOVE THE TSRA TO LESSER HOURS OR IMPACT. CEILINGS
WILL ALSO BE VERY DIFFICULT WITH MESSY...UNORGANIZED PATTERN
THROUGH THE PERIOD.
CONFIDENCE IS LOW IN THE TAF BEYOND 4-5 HOURS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR WIZ032>034-041>044-
053>055-061.
MN...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR MNZ079-086>088-
094>096.
IA...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR IAZ008>011-018-019-
029-030.
&&
$$
SHORT TERM...BAUMGARDT
LONG TERM....RRS
AVIATION...BAUMGARDT
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1228 PM CDT MON JUN 24 2013
UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND TUESDAY
ISSUED AT 444 AM CDT MON JUN 24 2013
THE CONTINUING SAGA ON WHERE AND WHEN FOR CONVECTION CONTINUES THIS
MORNING. LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY HINT AT
WEAK BOUNDARY OVER NORTHEAST WI SEEN IN DEW POINTS. AREA OF
DISORGANIZED TSTMS MOVING NORTH THROUGH IA AND WESTERN IL.
STARTING TO SEE MORE MOVEMENT TO EAST OVER IL IN LATEST SCANS WHICH
WOULD GO WITH MODELS PROJECTION OF LLVL JET SHIFTING MORE TO THE
WEST AND WEAKENING BY 12Z.
HRRR SEEMS TO HAVE BEST HANDLE ON CURRENT TRENDS...SHOWING ONLY
SPOTTY CONVECTION OVER CWA TODAY MAINLY OVER THE SOUTH HALF.
ALL MODELS STILL SHOWING VARIETY OF SOLUTIONS IN QPF PATTERN
THROUGH THIS PERIOD. HAVE TRENDED TOWARD NAM TODAY GIVEN DRIER
AIR WORKING IN AS SEEN IN SIG DROP IN PWATS ON MSP SOUNDING LAST
EVENING. SFC BASED INSTABILITY STILL SIG 1-2K...THOUGH NOT SEEING
ANY REAL TRIGGER/LIFT TODAY. WENT WITH SLIGHTS FOR LATE DAY
CONVECTION SOUTH AND EAST ALONG LAKE BREEZE BOUNDARY.
FORCING AND MOISTURE WORKS BACK INTO THE AREA THIS EVENING WITH
STRENGTHENING LLVL FLOW POINTING INTO SOUTHWEST WI AFTER
06Z. ALSO SEEING SOME SUPPORT FROM RRQ OF JET MAX MOVING THROUGH
LAKE SUPERIOR REGION. WILL GO WITH INCREASING CHANCE POPS TONIGHT
HIGH CHANCE POPS TUE AS FGEN/ISENTROPIC LIFT MAXIMIZED OVER CWA
FROM 12Z TO 18Z TUES. CWA REMAINS IN SLIGHT RISK AREA ON TUE.
SHEAR BETTER SOUTH FOR SOME WIND CONCERNS. WBZERO HGTS RATHER
HIGH FOR LARGE HAIL. WITH PWATS RETURNING TO 1.5 TO 2 INCHES AGAIN
HEAVY RAIN MORE OF CONCERN.
.LONG TERM...TUESDAY NIGHT THROUGH SUNDAY
ISSUED AT 444 AM CDT MON JUN 24 2013
500MB RIDGE EXPECTED TO BUILD ACROSS THE WESTERN UNITED STATES
WHILE UPPER TROUGH DEEPENS AND POSSIBLY CLOSES OFF ACROSS THE
WESTERN GREAT LAKES BY THE END OF THE WORK WEEK INTO NEXT WEEKEND.
FORECAST ISSUES ALREADY AT THE START OF THE PERIOD TUESDAY NIGHT.
HAVE CONCERNS ON THE PLACEMENT OF CONVECTION TUESDAY EVENING ACROSS
NORTHERN WISCONSIN. BELIEF IS THAT THE AXIS OF HEAVIER PRECIPITATION
TOO FAR NORTH. THINK BAND WILL BE FURTHER SOUTH AS FIRST COMPLEX OF
STORMS LATE MONDAY NIGHT AND TUESDAY WILL PUSH AN OUTFLOW BOUNDARY
SOUTHWARD THAN WHAT THE MODELS SHOW...SIMILAR TOO WHAT HAPPENED A
FEW DAYS AGO. GFS QPF FIELD SEEMS REASONABLE BASED ON MY CURRENT
THINKING. THIS COULD AFFECT THE RAIN CHANCES ACROSS THE NORTH
TUESDAY EVENING. SOUTHERN SECTIONS OF THE FORECAST AREA WILL BE
CLOSE ENOUGH TO STILL WARRANT LIKELY CHANCES. 500MB TROUGH SWINGS
INTO THE AREA TOWARDS 12Z WEDNESDAY...WARRANTING LIKELY POPS EVEN
ACROSS THE NORTH. UPPER TROUGH WILL SWING ACROSS THE AREA ON
WEDNESDAY. RAISED POPS TO 50 TO 55 PERCENT...AND MAY BUMP THEM
UP A LITTLE MORE BEFORE FORECAST ISSUANCE. THE UPPER TROUGH
SHOULD SWING EAST INTO LOWER MICHIGAN WEDNESDAY NIGHT. THERE WILL
STILL BE SOME LINGERING EVENING SHOWERS AND A FEW STORMS. MID
LEVEL LAPSE RATES NOT IMPRESSIVE...THEREFORE ONLY EXPECTED ISOLATED
NATURE OF ANY THUNDERSTORMS WEDNESDAY EVENING.
NORTHWEST FLOW ALOFT WILL CONTINUE THURSDAY AND FRIDAY...ALTHOUGH
A DEEPER 500MB TROUGH WILL SWING ACROSS THE AREA FRIDAY AFTERNOON AND
FRIDAY NIGHT. WILL CONTINUE THE SMALL CHANCES FOR SHOWERS SATURDAY...
BUT NOT TOO OPTIMISTIC WE WOULD SEE THEM AT THIS TIME SINCE UPPER
TROUGH WILL WELL EAST OF THE AREA WITH BUILDING HEIGHTS. CANADIAN
HIGH PRESSURE WILL DOMINATE THE WEATHER PATTERN ON SUNDAY...ALTHOUGH
COULD NOT RULE OUT A FEW ISOLATED SHOWERS SUNDAY AFTERNOON.
FOR THE MOST PART...VERIFICATION DATA HAS SHOWN WE AND NUMERICAL
GUIDANCE HAS BEEN TOO WARM OF LATE. DID NUDGE TEMPERATURES DOWN A
DEGREE OR TWO MOST PERIODS. WILL NEED TO WATCH WEDNESDAY...IF IT
STAYS CLOUDY AND THERE IS A LOT OF RAIN AROUND DURING THE DAY...
TEMPERATURES COULD STAY IN THE 70S.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1228 PM CDT MON JUN 24 2013
A THUNDERSTORM COMPLEX OVER SOUTHERN MINNESOTA AND IOWA IS EXPECTED
TO MOVE NORTHEAST THIS AFTERNOON INTO WISCONSIN. CURRENT TRENDS
SUPPORT CENTRAL AND NORTHEAST WISCONSIN RECEIVING SHOWERS AND
THUNDERSTORMS FROM THIS COMPLEX LATE THIS AFTERNOON AND INTO THE
EVENING. CIGS/VSBYS WILL LIKELY FALL INTO THE MVFR RANGE WITHIN ANY
THUNDERSTORMS. FOLLOWING THE PASSAGE OF THESE STORMS...WILL LIKELY
SEE A BREAK BUT UNCERTAINTY WILL BE HIGH AS TO HOW LONG. ITS QUITE
POSSIBLE THAT THE BREAK COULD LAST UNTIL TOMORROW AFTERNOON BEFORE
THE NEXT AROUND OF SHOWERS AND STORMS ARRIVE.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....TE
LONG TERM......ECKBERG
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1110 AM CDT MON JUN 24 2013
.UPDATE...NO CHANGES TO FLASH FLOOD WATCH HEADLINE. MAIN ACTION IN IOWA.
AIRMASS RELATIVELY MORE STABLE HERE IN SRN WI DUE TO CLOUD DEBRIS
FROM LATE NIGHT/EARLY MRNG MCS. NEW HRRR PUTS ERN IA AND NRN IL
MORE IN THE HOT SPOT THIS AFTERNOON AND THIS MAKES SENSE GIVEN THE
OUTLAW OF WHERE BETTER AIRMASS RESIDES TO SUPPORT SUSTAINED
STRONGER CONVECTION. MODELS ARE ALL SHOWING MORE CONVECTION
RE-FIRING TONIGHT ACRS SRN WI WITH ANOTHER 850 JET CORE ARRIVING
FROM THE SOUTHWEST...BUT LIKE LAST NIGHT WILL HAVE TO SEE HOW ALL
THIS ONGOING CONVECTION AFFECTS EFFECTIVE BOUNDARY
POSITION/AIRMASS CHARACTERISTICS AS WE HEAD INTO THE NIGHT. ALL
IN ALL FLASH FLOOD WATCH STILL LOOKS OK.
PC
&&
.AVIATION/18Z TAFS/...VFR CEILINGS FOR MUCH OF THE PERIOD.
CONVECTIVE TRENDS SUGGEST MAIN ACTION IN IOWA WILL MORE THAN
LIKELY AFFECT ERN IA AND NRN IL INTO THE EARLY EVENING...POSSIBLY
GRAZING THE FAR SOUTH...PER HRRR. POTENTIAL FOR CONVECTION TONIGHT
WILL DEPEND ON HOW THE ONGOING STORMS IN IOWA DISTRIBUTES
BOUNDARIES AND HOW THESE INTERACT WITH RENEWED 850 JET FOR THE
EVENING AND OVERNIGHT.
PC
&&
.PREV DISCUSSION... /ISSUED 412 AM CDT MON JUN 24 2013/
SHORT TERM...
TODAY AND TONIGHT-FORECAST CONFIDENCE MEDIUM.
FIRST CONCERN IS ONGOING MCS IN IOWA ON NOSE OF LOW LEVEL JET.
MODELS POINT NOSE OF JET FARTHER NORTH AND EAST DURING THE EARLY
MORNING SO THIS WILL COMING INTO MAINLY SOUTHWEST PARTS OF THE AREA
THAT WERE POUNDED BY HEAVY RAIN A COUPLE OF DAYS AGO. SEEMS THAT
RIGHT ENTRANCE REGION OF 90 KNOT 250 MB WIND MAX IN MN MAY BE AIDING
THESE STORMS.
OTHERWISE PERSISTENT 850-700 MB WARM ADVECTION WITHIN BROAD 850 MB
LOW LEVEL JET AND MOIST AIRMASS SHOULD YIELD SCATTERED TO NUMEROUS
THUNDERSTORMS TODAY AND TONIGHT.
TIMING AND LOCATION DIFFICULT AS USUAL WITH CONVECTION AND
ASSOCIATED MESOSCALE OUTFLOW BOUNDARIES BUT PRECIPITABLE WATER
VALUES WILL BE IN 130-160% OF NORMAL RANGE SO POTENTIAL FOR HEAVY
RAIN TO CONTINUE. FRANKLY YOU COULD EXTEND THE FLASH FLOOD WATCH
UNTIL WEDNESDAY MORNING BUT AFTER DISCUSSING THE MATTER WITH
SURROUNDING WFOS SEEMS THAT WE SHOULD FOCUS ON THE NEXT 12-24
HOURS. AFTER MUCH DELIBERATION DECIDED TO MATCH UP WITH ARX AND
EXTEND THE WATCH UNTIL 10 AM ON TUESDAY.
THESE SITUATIONS ARE ALWAYS DIFFICULT BECAUSE TRYING TO FORECAST QPF
FOR THE WHOLE AREA WITHOUT KNOWING WHICH COUPLE OF COUNTIES WILL GET
HIT WITH 3-5 INCHES OF RAIN OR MORE IS ALMOST IMPOSSIBLE. SO WE
BROAD BRUSH 0.50 TO 1.00" QPF KNOWING THAT SOME AREAS WILL GET VERY
LITTLE RAIN AND OTHERS MUCH MORE.
MARGINAL HAIL AND WIND THREAT EXISTS BUT SHOULD BE RELATIVELY MINOR
IN COMPARISON TO TUESDAY EVENING.
TUESDAY THROUGH WEDNESDAY NIGHT...FORECAST CONFIDENCE MEDIUM.
UNSETTLED PERIOD WITH MODELS PUTTING OUT A LOT OF CONVECTIVE DRIVEN
PRECIP AS THE WET AND HUMID PATTERN CONTINUES. MODELS ARE IN A
GENERAL/BROAD AGREEMENT REGARDING THE NEAR-ZONAL PATTERN AND A FEW
SHORT WAVE TROUGHS RIPPLING THROUGH. THE MAIN CONCERN IS TUESDAY
INTO WEDNESDAY. A SHORT WAVE TROUGH WILL BEGIN TO MOVE ACROSS THE
CWA LATE TUESDAY...WHERE THE BEST CHANCES FOR PRECIP ARE. LIKELY
POPS ACROSS MUCH OF THE CWA FROM 0Z TO 12Z WEDNESDAY WHERE DECENT
SYNOPTIC ASCENT...WITH Q-VECTOR DIVG AND LOW-LEVEL WAA...WILL
COINCIDE WITH A LLJ THAT WILL INITIAL TAKE AIM AT SOUTH CENTRAL
WI. THE LLJ THEN BECOMES MORE WSW BY 12Z WED. SFC LOW PRESSURE
TROUGH AND BOUNDARY EXPECTED TO BE OVER CENTRAL WI AT THIS TIME
TUESDAY AFTERNOON. GIVEN THE SETUP...DO CONCUR WITH PREV FCST
DISCUSSION CONCEPTUALLY ON A MCS TRAVERSING THE CWA GIVEN THE
LLJS FOCUS.
FLASH FLOOD/HEAVY RAIN POTENTIAL THIS PERIOD...WITH HIGH
PRECIPITABLE WATER VALUES AROUND 1.7-1.9 AT ITS PEAK IN THE
EVENING TUES/EARLY WED. STRONG THUNDERSTORM THREAT AS WELL TUESDAY
AND WEDNESDAY GIVEN ENVIRONMENT WITH AMPLE INSTABILITY AND
MOISTURE. OF NOTE...DEEP LAYER SHEAR MORE ROBUST THAN WE HAVE SEEN
PREVIOUSLY THE LAST FEW DAYS...WITH VALUES AROUND 20-30 KTS.
THUS...A DECENT SIGNAL IN SIGSVR ALSO. THE POTENTIAL FOR A WIND
AND HAIL THREAT DOES EXIST. A SLIGHT RISK IS PRESENT FOR ALL OF
THE CWA IN SPCS DAY 2 CATEGORICAL OUTLOOK THIS MORNING. SPC
OUTLOOK ON DAY 3 HAS THE EASTERN TWO THIRDS OF THE CWA IN SLIGHT
RISK ALSO.
HIGHS WERE LOWERED A BIT TUES AND WED...AND LEANED MORE TOWARDS
THE COOLER CONSENSUS GUIDANCE GIVEN THE SKY COVER ANTICIPATED AND
MOIST COLUMNS.
LONG TERM...
THURSDAY THROUGH SUNDAY NIGHT...FORECAST CONFIDENCE MEDIUM.
COOLING TREND BEGINS FRIDAY/THIS WEEKEND. MODELS IN AGREEMENT WITH
THE FLOW BECOMING MORE AMPLIFIED WITH A LONG WAVE TROUGH DIGGING
INTO THE GREAT LAKES REGION. GFS CONTINUES TO DIG NOTABLY
STRONGER WITH LARGER HT FALLS COMPARED TO NAM AND ECMWF. NW FLOW
THEN TAKES OVER THIS WEEKEND WITH COOLER TEMPS ALOFT BROUGHT
TOWARDS WISCONSIN. SFC HIGH PRESSURE BEGINS TO BUILDS IN SUNDAY
AND PERSIST THROUGH THE BEGINNING OF MONDAY.
AVIATION/12Z TAFS/...
AS IS TYPICAL IN CONVECTIVE SITUATIONS...MUCH OF THE TIME WILL BE
VFR WITH BRIEF AND DIFFICULT TO TIME PERIODS OF MVFR OR LOWER.
PRETTY MUCH A COIN TOSS PROBABILITY NEXT 24 HOURS SO WILL BE
CONSERVATIVE.
SEEMS THAT MORNING MCS MOVING OUT OF IOWA AND NORTHERN ILLINOIS WILL
MAINLY JUST BRUSH THE TAF SITES BUT SEVERAL ROUNDS ARE POSSIBLE BUT
ESPECIALLY TONIGHT AS AFTERNOON ACTIVITY MOVES ON NOSE OF LOW LEVEL
JET FROM IOWA AND MINNESOTA INTO WISCONSIN.
PESKY MVFR FOG IS POSSIBLE THIS MORNING AND AGAIN TONIGHT WITH HIGH
DEW POINTS BUT PROBABILITY IS A TAD LOW TO PUT IN TAFS.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR WIZ046-047-056-057-
062-063-067>069.
LM...NONE.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...CRAVEN
TUESDAY THROUGH SUNDAY...ET