Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/23/13
AREA FORECAST DISCUSSION
NWS PUEBLO CO
933 PM MDT SAT JUN 22 2013
NEW FIRE WEATHER SECTION
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 257 PM MDT SAT JUN 22 2013
...CRITICAL FIRE WEATHER CONDITIONS CONTINUE...
CURRENTLY...A SHORTWAVE TROUGH IS CURRENTLY MOVING ACROSS WYOMING
WITH THE BASE DOWN ACROSS NORTH CENTRAL COLORADO. THIS HAS LED TO
CUMULUS DEVELOPMENT FROM NEAR GUNNISON NORTHEAST THROUGH THE PALMER
DIVIDE. INSTABILITY IS WEAK WHICH SHOULD HELP KEEP THUNDERSTORM
ACTIVITY FROM DEVELOPING THIS AFTERNOON AND EVENING. SMOKE FROM THE
WEST FORK COMPLEX IS MAKING ITS DAILY SHIFT EASTWARD AND IMPACT MOST
OF THE REGION...ESPECIALLY THE SAN LUIS VALLEY...PUEBLO AND COLORADO
SPRINGS. TEMPERATURES ARE WARM WITH MID TO UPPER 90S ACROSS MUCH OF
THE LOWER ELEVATIONS. WINDS HAVE BEEN GUSTY...WITH 25 TO 30 KTS FOR
AREAS ALONG AND WEST OF I-25 AND HUMIDITY VALUES HAVE FALLEN TO LESS
THAN 10 PERCENT FOR MUCH OF THE AREA.
TONIGHT...THE SHORTWAVE OVER WYOMING WILL LIFT OFF TO THE NORTHEAST
OVERNIGHT. A WEAK COLD FRONT IS FORECAST TO DROP SOUTH ACROSS THE
EASTERN PLAINS BY 06Z. FOLLOWED A BLEND OF THE VARIOUS WRF
SOLUTIONS AS FAR AS FRONTAL PROGRESS. THE HIGH RES SOLUTIONS STALL
THE FRONT FROM NEAR COLORADO SPRINGS...SOUTHEAST TO NEAR
SPRINGFIELD. WINDS NORTH OF THE BOUNDARY WILL REMAIN NORTHERLY
WHILE AREAS SOUTH OF THE BOUNDARY MAINTAIN THEIR BREEZY SOUTHWEST
CONDITIONS. THIS WILL ALSO KEEP HUMIDITY VALUES FROM RECOVERING
MUCH SOUTH OF THE FRONT...WHILE MOISTURE POOLS TO THE NORTH.
OVERNIGHT LOWS WILL REMAIN MILD WITH 50S TO 60S FOR THE PLAINS.
SMOKE WILL IMPACT THE REGION THROUGH THE EVENING...WITH IMPROVING
CONDITIONS BEHIND THE FRONT AS NORTH WINDS SHIFT THE SMOKE SOUTH AND
MIX IT OUT.
SUNDAY...ANOTHER DANGEROUS FIRE WEATHER DAY ON STORE FOR MUCH OF
SOUTH CENTRAL COLORADO. THE FRONT THAT IS STALLED OVER THE PLAINS
WILL EVENTUALLY TRANSITION SOUTHWARD DURING THE MORNING HOURS WITH
SOUTHEASTERLY FLOW DEVELOPING THROUGH THE AFTERNOON. HIGH RES
SOLUTIONS KEEP A PUSH OF SOUTHWESTERLY FLOW ACROSS THE RATON MESA
AREA WHICH WILL LIKELY KEEP THE EAST PEAK FIRE ACTIVE. THEREFORE
HAVE THE HIGHEST FIRE WEATHER DANGER OVER THE SAN JUANS...LA
GARITAS...THE SAN LUIS VALLEY...AND EASTERN MOUNTAINS. LESS
CONFIDENCE OVER EASTERN HUERFANO AND WESTERN LAS ANIMAS COUNTIES
WHICH SHOULD BE MONITORED...AND DEPEND ON HOW FAR EAST THE
SOUTHWESTERLY PUSH MAKES IT. EXTREME CAUTION IS ADVISED OVER THIS
REGION DUE TO THE DANGEROUS FIRE WEATHER CONDITIONS. IN
ADDITION...THERE IS A SLIM SEVERE WEATHER RISK OVER KIOWA AND
PROWERS COUNTIES SUNDAY AFTERNOON AND EVENING. MOISTURE POOLED
BEHIND THE FRONT AND WEAK ENERGY IN THE SOUTHWEST FLOW ALOFT WILL
LEAD TO THIS CHANCE. DAMAGING WINDS AND LARGE HAIL WILL BE POSSIBLE
WITH ANY STORMS THAT DO FORM...BUT CURRENT POPS ARE ONLY ABOUT 10 TO
15 PERCENT. THIS WILL NEED TO BE WATCHED. MOZLEY
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 257 PM MDT SAT JUN 22 2013
MAINLY DRY...SW FLOW ALOFT WL CONTINUE OVR THE AREA SUN NIGHT AND
MON. WL GO WITH A DRY FORECAST FOR MON ALONG WITH BREEZY
CONDITIONS...ONCE AGAIN LEADING TO THE POTENTIAL FOR CRITICAL FIRE
WEATHER CONDITIONS. WL ISSUE A FIRE WX WATCH FOR THE I-25
CORRIDOR...THE ERN MTS...THE SAN LUIS VALLEY AND THE SOUTHWEST CO
MTNS...WHERE IT LOOKS LIKE RH AND WIND CRITERIA COULD BE MET...ALONG
WITH FUELS BEING DRY IN THESE AREAS. ON TUE THE FLOW ALOFT BECOMES
MORE WESTERLY BUT THERE IS STILL LITTLE MOISTURE AND WL GO WITH
ANOTHER DRY AND HOT FORECAST. IN GENERAL...THE SFC WINDS ON TUE
LOOK A BIT LIGHTER AND THUS THERE SHOULD BE LESS OF A THREAT FOR
CRITICAL FIRE WX CONDITIONS.
WED AN UPR RIDGE IS FORECAST TO BE CENTERED OVR SRN CO AND NRN
NM...WHICH THEN SHIFTS WESTWARD OVER UT AND AZ FOR THU THRU SAT.
A LITTLE MSTR TRAPPED UNDER THE RIDGE COULD LEAD TO MAINLY A FEW
MOUNTAIN SHOWERS/TSTMS. WITH LIGHTER WINDS EXPECTED UNDER THE
RIDGE...THERE WL BE LESS OF A CHANCE FOR FIRE WX CONCERNS. TEMPS
WL REMAIN QUITE WARM EACH DAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 257 PM MDT SAT JUN 22 2013
VFR CONDITIONS AT ALL TERMINALS THROUGH MUCH OF THE FORECAST PERIOD.
SOUTHWEST WINDS WITH WIDESPREAD GUSTS 25-30 KTS POSSIBLE AT ALL
TERMINALS THROUGH EARLY EVENING. SMOKE FROM FIRES OVER THE
CONTINENTAL DIVIDE WILL ALSO MOVE OVER AREA TERMINALS BY LATE
AFTERNOON AND EVENING WHICH MAY REDUCE VISIBILITIES TO NEAR MVFR
LEVELS...ESPECIALLY AT KPUB AND KCOS. A WEAK COLD FRONT WILL MOVE SOUTH
ACROSS KCOS AND KPUB AFTER 06Z TONIGHT WITH A NORTHERLY WIND SHIFT.
MOZLEY
&&
.FIRE WEATHER...
ISSUED AT 933 PM MDT SAT JUN 22 2013
WILL NOT MAKE ANY CHANGES TO THE RED FLAG WARNING FOR SUNDAY.
LATEST NAM..RUC...AND HRRR ARE MORE OPTIMISTIC FOR LOW LEVEL
MOISTURE REACHING FIRE WEATHER ZONES 229 AND 230. SUSPECT
SOUTHEAST WINDS WILL REMAIN IN THESE ZONES WELL INTO THE
AFTERNOON. WHILE HUMIDITIES MAY FALL TO 15 PERCENT OR LOWER DURING
THE AFTERNOON...SOUTHEAST WINDS WILL CONTINUE WITH SPEEDS BELOW
RED FLAG CRITERIA. UNFORTUNATELY...MOISTURE WILL NOT BE DEEP
ENOUGH TO ANY PRECIPITATION...EXCEPT PERHAPS CLOSER TO THE KANSAS
BORDER. LOW LEVEL MOISTURE WILL REACH THE EASTERN SLOPES OF THE
EASTERN MOUNTAINS AND MAY BRIEFLY REACH INTO THE SAN LUIS VALLEY.
HOWEVER...ANY MOISTURE IN THE EASTERN MOUNTAINS AND HIGH VALLEYS
WILL MIX OUT DURING THE MORNING. TROUGH PASSING THROUGH ZONE 220
WILL KEEP HUMIDITIES JUST HIGH ENOUGH FOR RED FLAG CONDITIONS NOT
TO BE REACHED. WILL UPDATE GRIDS GRIDS SHORTLY BASED ON NEW NAM
AND MET GUIDANCE. --PGW--
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM MONDAY MORNING THROUGH MONDAY EVENING
FOR COZ221>230.
RED FLAG WARNING FROM 11 AM TO 8 PM MDT SUNDAY FOR COZ223>225.
&&
$$
SHORT TERM...MOZLEY
LONG TERM...28
AVIATION...MOZLEY
FIRE WEATHER...PGW
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
801 PM MDT SAT JUN 22 2013
.UPDATE...CLUSTER OF SHOWERS AND THUNDERSTORMS OVER THE
NORTHEAST CORNER OF COLORADO WILL EXIT THE STATE THIS EVENING YET.
AN UPPER LEVEL TROUGH MOVING OUT OF THE GREAT BASIN AND NORTHERN
ROCKIES HAS PRODUCED LIFT OVER THE HIGHER TERRAIN. HOWEVER...JUST
VIRGA OR LIGHT RAIN HAS FALLEN BECAUSE OF THE DRY AIRMASS IN PLACE.
A WEAK COLD FRONT...MERGED WITH OUTFLOW FROM THUNDERSTORMS OVER
WYOMING...IS MOVING SOUTH INTO NORTHEAST COLORADO. THIS HAS
TRIGGERED A THUNDERSTORM JUST EAST OF CHEYENNE. BECAUSE OF THIS
AND THE UPPER LEVEL DISTURBANCE TO THE WEST...WILL KEEP 10-20
POPS IN THROUGH THE EVENING. THE RAP/NAM SHOWING SOME LOW CLOUDS
TOWARDS DAY BREAK. DID ADD SOME CLOUDS TO THE FORECAST FOR AFTER
MIDNIGHT.
&&
.AVIATION...EASTERLY WINDS WILL TURN NORTHERLY AROUND 05Z AS COLD
FRONT FROM WYOMING PUSHES THROUGH THE DENVER AREA. THIS WILL
INCREASE LOW LEVEL MOISTURE AND PERHAPS BRING LOW CLOUDS FROM
10-15Z SUNDAY MORNING. SOME MODELS SHOW LOW CLOUDS AND SOME DON`T.
CURRENT TAF HANDLES THIS WITH A FEW AT 2000 FEET. WILL ADD MORE
LOW CLOUDS AT THE 06Z TAF ISSUANCE IF MODELS CONTINUE TO TREND
TOWARD LOW CLOUDS. THERE WILL BE ANOTHER CHANCE FOR LATE DAY
SHOWERS AND STORMS ON SUNDAY.
&&
.PREV DISCUSSION... /ISSUED 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
UPDATE/AVIATION...MEIER
AREA FORECAST DISCUSSION
NWS ALBANY NY
729 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/...
MAINLY VFR CONDITIONS ARE EXPECTED THROUGH SUNDAY. HOWEVER...THERE
COULD BE SOME FOG ISSUES OVERNIGHT. IT NOW APPEARS THE CLOUDS COULD
EVEN THIN ENOUGH FOR SOME FOG TO FORM AT KGFL. HOWEVER...COUNTERING
THAT WOULD BE A LIGHT BREEZE...EXPECTED TO REMAIN UP MUCH OF THE
NIGHT AT THE SITE. FOR NOW...WE MENTIONED VCFG THERE BETWEEN 08Z-11Z
TO COVER UNCERTAINTY. THIS ALSO ASSUMED THAT WIDELY SCATTERED
SHOWERS (VCSH) DOES NOT WET THE GROUND EXTENSIVELY. WIDELY SCATTERED
SHOWERS ARE EXPECTED TO CONTINUE THROUGHOUT THE EVENING IN RESPONSE
TO A VERY WEAK DISTURBANCE MOVING OVERHEAD.
WE WILL CONTINUE THE IDEA OF MVFR FOG AT KPOU AND KPSF OVERNIGHT
SINCE LESS IN THE WAY OF CLOUDS ARE EXPECT THERE AS WELL AS PERHAPS
A LIGHTER BREEZE.
AFTER SUNRISE...ANY FOG WILL DISSIPATE AND VFR CONDITIONS WILL BE
IN PLACE FOR ALL TERMINALS. CLOUDS SHOULD SCT OUT FOR THE REMAINDER
OF THE MORNING THROUGH MIDDAY...ALTHOUGH ADDITIONAL SHOWERS ARE
POSSIBLE LATER ON SUNDAY. FOR NOW...WENT THE VCSH CONCEPT FROM
MIDDAY ON.
A SOUTH TO SOUTHWEST WIND WILL BE AROUND 5KTS TONIGHT...INCREASING
TO NEARLY 10KTS LATER ON SUNDAY.
OUTLOOK...
SUN NITE-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...HWJIV
FIRE WEATHER...BGM
HYDROLOGY...BGM
AREA FORECAST DISCUSSION
NWS ALBANY NY
636 AM EDT FRI JUN 21 2013
.SYNOPSIS...
HIGH PRESSURE WILL TAKE UP RESIDENCE JUST OFF THE EASTERN SEABOARD
TODAY INTO THE WEEKEND. A SOUTHWESTERLY FLOW AROUND THIS HIGH
PRESSURE AREA WILL RESULT IN WARMER TEMPERATURES AND RISING LEVELS
OF HUMIDITY. ISOLATED TO SCATTERED SHOWERS OR THUNDERSTORMS WILL BE
POSSIBLE EACH DAY...MAINLY DURING THE AFTERNOON AND EVENING HOURS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 630 AM EDT...AS HIGH PRESSURE SETTLES IN JUST OFF THE
EASTERN SEABOARD TODAY...A RETURN WEST-SOUTHWEST FLOW ALOFT WILL
DEVELOP AND ALLOW TEMPERATURES TO WARM MORE THAN PREVIOUS DAYS.
NAM/GFS STILL SHOWING A SUBTLE LOW LEVEL CONVERGENCE ZONE SETTING
UP FROM JUST SOUTH OF KALB TO NEAR KPOU...MAINLY SEEN ON SURFACE
WIND FIELDS. INSPECTING HIGHER RESOLUTION MODELS...THE 4KM WRF-
NMM...LOCAL HIRESWRF AND EVEN THE HRRR SHOWING A FEW CELLS POPPING
UP IN THE GENERAL VICINITY OF THE CONVERGENCE ZONE THIS AFTERNOON.
COVERAGE LOOKS TO BE ISOLATED AT BEST...WITH MOST OF THE AREA
ESPECIALLY FROM ALBANY NORTHWARD REMAINING DRY. INSTABILITY LOOKS
MEAGER...BUT GIVEN SLIGHTLY HIGHER DEWPOINTS AND TEMPS IN THE
80S...WILL MENTION POSSIBLE THUNDER. THERE MAY BE A FEW MORE
CLOUDS AROUND THAN PRIOR DAYS...BUT SKIES SHOULD STILL AVERAGE
MOSTLY-PARTLY SUNNY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
ANY ISOLATED CONVECTION WILL QUICKLY DIMINISH THIS EVENING WITH LOSS
OF DAYTIME HEATING. TEMPERATURES WILL BE MILDER THAN THE PAST FEW
NIGHT DUE TO CONTINUED WARMING ALOFT.
THE WEEKEND WILL FEATURE SUMMER-LIKE WARMTH ALONG WITH THE CHANCE
FOR SOME THUNDERSTORMS...WHICH WILL MAINLY BE DIURNALLY DRIVEN.
THERE ARE SOME SUBTLETIES THAT WILL HAVE AN IMPACT ON
COVERAGE/TIMING OF CONVECTION.
ON SATURDAY...THE REGION WILL STILL BE UNDER THE INFLUENCE OF A W-NW
FLOW ALOFT ON THE NORTHERN PERIPHERY OF A BUILDING UPPER LEVEL RIDGE
OVER THE OHIO VALLEY AND MID ATLANTIC REGION. VARIOUS SOURCES OF
GUIDANCE INDICATING A WEAK DISTURBANCE OR TWO EMBEDDED IN THE FLOW
WILL PASS THROUGH MAINLY THE NORTHERN HALF OF THE AREA. THIS COULD
BE ENOUGH FORCING TO TRIGGER SCATTERED CONVECTION GIVEN AN INCREASE
IN LOW LEVEL DEWPOINTS AND PRECIPITABLE WATER NEARING OR EXCEEDING
1.5 INCHES. WILL MENTION CHANCE POPS ACROSS THE NORTHERN 2/3 OF THE
AREA...WITH SLIGHT CHANCE SOUTH. SBCAPE GENERALLY FORECAST TO BE
AROUND 500-1000 J/KG...WITH 850-500MB LAPSE RATES ONLY AROUND 5.5 TO
6.0 C/KM...SO T-STORMS ARE NOT EXPECTED TO BE SEVERE. DEPENDING ON
EVENTUAL DEGREE OF CLOUD COVER SATURDAY AFTERNOON...TEMPERATURES
COULD REACH THE MID 80S IN MOST VALLEY LOCATIONS.
CONVECTION SHOULD DIMINISH DURING THE EVENING HOURS AS DAYTIME
HEATING IS LOST AND THE UPPER LEVEL DISTURBANCES MOVE EAST OF THE
REGION.
SUNDAY MAY FEATURE ADDITIONAL MAINLY SCATTERED SHOWERS AND
T-STORMS...WHICH SHOULD BE DIURNALLY DRIVEN AND POSSIBLY EVEN TIED
TO TERRAIN/DIFFERENTIAL HEATING AREAS AS THE UPPER RIDGE BUILDS
ACROSS THE AREA. THE NAM IS DEPICTING A FLATTER FLOW REGIME
ALOFT...WHILE THE GFS/ECMWF TENDS TO BUILD THE UPPER RIDGE MORE.
SINCE IT IS A COUPLE DAYS AWAY...THERE IS QUITE A BIT OF UNCERTAINTY
AS TO THE DEGREE OF CONVECTION THAT EVOLVES. WILL MENTION LOW CHANCE
POPS FOR MUCH OF THE AREA...WITH SLIGHT CHANCE SOUTH. WILL HAVE TO
WATCH UPSTREAM OVER THE UPPER GREAT LAKES FOR ANY CONVECTIVE
FOOTPRINTS THAT MAY EVENTUALLY IMPACT THE REGION...ESPECIALLY IF WE
REMAIN ON THE NORTHERN PERIPHERY OF THE UPPER RIDGE. SUNDAY SHOULD
BE THE WARMEST DAY SINCE JUNE 2ND ACROSS THE AREA AS ADDITIONAL
WARMING ALOFT OCCURS WITH MID TO UPPER 80S EXPECTED FOR MUCH OF THE
REGION.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
FLAT BROAD UPPER RIDGING SHOULD SET UP OVER EASTERN NORTH AMERICA
WITH SMALL PIECES OF UPPER LEVEL ENERGY TRACKING AROUND THE NORTHERN
PERIPHERY OF THE RIDGE MONDAY THROUGH TUESDAY NIGHT. THESE LITTLE
PIECES OF UPPER ENERGY SHOULD ENHANCE THE THREAT OF SHOWERS/TSTMS
EACH AFTN/EVENING AND HAVE FORECAST 30 TO 40 PERCENT POPS EACH
AFTN/EVENING...AND 20 TO 30 PERCENT POPS DURING THE OVERNIGHT AND
MORNING HOURS. FOR SUNDAY NIGHT HAVE FORECAST DRY CONDITIONS.
ALTHOUGH NOT AS IMPRESSIVE AS LAST NIGHT...THE GFS/ECMWF STILL SHOW
A DEEPENING UPPER LEVEL TROF WILL MOVE INTO THE REGION BY WEDNESDAY
AFTN WITH AN EVEN GREATER THREAT FOR SHOWERS/TSTMS WED AFTN THROUGH
THURSDAY. FOR EACH AFTN/EVENING DURING THIS PERIOD HAVE FORECAST 40
TO 50 PERCENT POPS...AND 30 TO 40 PERCENT DURING THE OVERNIGHT
AND EARLY MORNING HOURS.
IT WILL BE VERY WARM OR HOT EARLY IN THE LONG TERM PERIOD...WITH A
BIT OF A COOL DOWN WEDNESDAY AND THURSDAY AS THE UPPER LEVEL TROF
MOVES INTO THE REGION. IT WILL BE HUMID DURING THE ENTIRE PERIOD
WITH DEWPOINTS GENERALLY IN THE 60S.
HIGHS MONDAY AND TUESDAY WILL BE IN THE 80S TO AROUND 90...THEN
UPPER 70S AND 80S WEDNESDAY...AND MID 70S TO LOWER 80S THURSDAY.
LOWS WILL GENERALLY BE IN THE UPPER 50S AND 60S SUNDAY NIGHT THROUGH
WEDNESDAY NIGHT.
&&
.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
ANY LEFTOVER FOG AT KGFL/KPSF WILL HAVE DISIPATED BY THE START
OF THE NEW TAF PERIOD (12Z). SO EXPECT VFR CONDITIONS AT THE
KALB/KPOU/KGFL/KPSF TAF SITES THROUGH TONIGHT. THE EXCEPTION WILL BE
POSSIBLE LATE NIGHT MVFR/IFR FOG AT KGFL/KPSF. WITH HIGH PRESSURE
OVER THE REGION CONDITIONS WILL BE MAINLY P6SM SCT250 WITH A FEW
CUMULUS CLOUDS THIS AFTERNOON. LATE TONIGHT THE HIGH CLOUDS SHOULD
BECOME BKN.
LIGHT SURFACE WINDS EARLY THIS MORNING WILL BECOME SOUTH TO
SOUTHWEST AT LESS THAN 8 KTS DURING THE REST OF FRIDAY...THEN MAINLY
CALM WINDS AGAIN TONIGHT.
OUTLOOK...
SAT...MAINLY VFR. SLGT CHC -TSRA/-SHRA.
SUN-TUE...MAINLY VFR. CHC -TSRA/-SHRA.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS CONTINUE DUE TO THE PAST SEVERAL WEEKS OF
WET WEATHER.
HIGH PRESSURE WILL MOVE OFF THE EAST COAST TODAY INTO THE WEEKEND.
ISOLATED TO SCATTERED SHOWERS OR THUNDERSTORMS ARE POSSIBLE FROM
THIS AFTERNOON AFTERNOON THROUGH THE WEEKEND...ALONG WITH A GRADUAL
WARMING TREND. DEW FORMATION SHOULD OCCUR EACH NIGHT WITH THE RISING
LEVELS OF HUMIDITY.
&&
.HYDROLOGY...
FLOWS REMAIN ABOVE NORMAL ACROSS THE HYDRO SERVICE AREA.
FROM TODAY INTO EARLY NEXT WEEK...THERE MAY ISOLATED TO SCATTERED
SHOWERS OR THUNDERSTORMS...BUT WIDESPREAD RAINFALL IS NOT
ANTICIPATED AT THIS TIME...AND NOT ALL LOCATIONS WILL SEE RAINFALL.
THUS...RIVER LEVELS ARE EXPECTED TO CONTINUE TO GRADUALLY RECEDE
DURING THIS TIME.
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...JPV
NEAR TERM...JPV
SHORT TERM...JPV
LONG TERM...GJM
AVIATION...GJM
FIRE WEATHER...FRUGIS/JPV
HYDROLOGY...FRUGIS/JPV
AREA FORECAST DISCUSSION
NWS ALBANY NY
416 AM EDT FRI JUN 21 2013
.SYNOPSIS...
HIGH PRESSURE WILL TAKE UP RESIDENCE JUST OFF THE EASTERN SEABOARD
TODAY INTO THE WEEKEND. A SOUTHWESTERLY FLOW AROUND THIS HIGH
PRESSURE AREA WILL RESULT IN WARMER TEMPERATURES AND RISING LEVELS
OF HUMIDITY. ISOLATED TO SCATTERED SHOWERS OR THUNDERSTORMS WILL BE
POSSIBLE EACH DAY...MAINLY DURING THE AFTERNOON AND EVENING HOURS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 415 AM EDT...AS HIGH PRESSURE SETTLES IN JUST OFF THE
EASTERN SEABOARD TODAY...A RETURN WEST-SOUTHWEST FLOW ALOFT WILL
DEVELOP AND ALLOW TEMPERATURES TO WARM MORE THAN PREVIOUS DAYS.
NAM/GFS STILL SHOWING A SUBTLE LOW LEVEL CONVERGENCE ZONE SETTING
UP FROM JUST SOUTH OF KALB TO NEAR KPOU...MAINLY SEEN ON SURFACE
WIND FIELDS. INSPECTING HIGHER RESOLUTION MODELS...THE 4KM WRF-
NMM...LOCAL HIRESWRF AND EVEN THE HRRR SHOWING A FEW CELLS POPPING
UP IN THE GENERAL VICINITY OF THE CONVERGENCE ZONE THIS AFTERNOON.
COVERAGE LOOKS TO BE ISOLATED AT BEST...WITH MOST OF THE AREA
ESPECIALLY FROM ALBANY NORTHWARD REMAINING DRY. INSTABILITY LOOKS
MEAGER...BUT GIVEN SLIGHTLY HIGHER DEWPOINTS AND TEMPS IN THE
80S...WILL MENTION POSSIBLE THUNDER. THERE MAY BE A FEW MORE
CLOUDS AROUND THAN PRIOR DAYS...BUT SKIES SHOULD STILL AVERAGE
MOSTLY-PARTLY SUNNY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
ANY ISOLATED CONVECTION WILL QUICKLY DIMINISH THIS EVENING WITH LOSS
OF DAYTIME HEATING. TEMPERATURES WILL BE MILDER THAN THE PAST FEW
NIGHT DUE TO CONTINUED WARMING ALOFT.
THE WEEKEND WILL FEATURE SUMMER-LIKE WARMTH ALONG WITH THE CHANCE
FOR SOME THUNDERSTORMS...WHICH WILL MAINLY BE DIURNALLY DRIVEN.
THERE ARE SOME SUBTLETIES THAT WILL HAVE AN IMPACT ON
COVERAGE/TIMING OF CONVECTION.
ON SATURDAY...THE REGION WILL STILL BE UNDER THE INFLUENCE OF A W-NW
FLOW ALOFT ON THE NORTHERN PERIPHERY OF A BUILDING UPPER LEVEL RIDGE
OVER THE OHIO VALLEY AND MID ATLANTIC REGION. VARIOUS SOURCES OF
GUIDANCE INDICATING A WEAK DISTURBANCE OR TWO EMBEDDED IN THE FLOW
WILL PASS THROUGH MAINLY THE NORTHERN HALF OF THE AREA. THIS COULD
BE ENOUGH FORCING TO TRIGGER SCATTERED CONVECTION GIVEN AN INCREASE
IN LOW LEVEL DEWPOINTS AND PRECIPITABLE WATER NEARING OR EXCEEDING
1.5 INCHES. WILL MENTION CHANCE POPS ACROSS THE NORTHERN 2/3 OF THE
AREA...WITH SLIGHT CHANCE SOUTH. SBCAPE GENERALLY FORECAST TO BE
AROUND 500-1000 J/KG...WITH 850-500MB LAPSE RATES ONLY AROUND 5.5 TO
6.0 C/KM...SO T-STORMS ARE NOT EXPECTED TO BE SEVERE. DEPENDING ON
EVENTUAL DEGREE OF CLOUD COVER SATURDAY AFTERNOON...TEMPERATURES
COULD REACH THE MID 80S IN MOST VALLEY LOCATIONS.
CONVECTION SHOULD DIMINISH DURING THE EVENING HOURS AS DAYTIME
HEATING IS LOST AND THE UPPER LEVEL DISTURBANCES MOVE EAST OF THE
REGION.
SUNDAY MAY FEATURE ADDITIONAL MAINLY SCATTERED SHOWERS AND
T-STORMS...WHICH SHOULD BE DIURNALLY DRIVEN AND POSSIBLY EVEN TIED
TO TERRAIN/DIFFERENTIAL HEATING AREAS AS THE UPPER RIDGE BUILDS
ACROSS THE AREA. THE NAM IS DEPICTING A FLATTER FLOW REGIME
ALOFT...WHILE THE GFS/ECMWF TENDS TO BUILD THE UPPER RIDGE MORE.
SINCE IT IS A COUPLE DAYS AWAY...THERE IS QUITE A BIT OF UNCERTAINTY
AS TO THE DEGREE OF CONVECTION THAT EVOLVES. WILL MENTION LOW CHANCE
POPS FOR MUCH OF THE AREA...WITH SLIGHT CHANCE SOUTH. WILL HAVE TO
WATCH UPSTREAM OVER THE UPPER GREAT LAKES FOR ANY CONVECTIVE
FOOTPRINTS THAT MAY EVENTUALLY IMPACT THE REGION...ESPECIALLY IF WE
REMAIN ON THE NORTHERN PERIPHERY OF THE UPPER RIDGE. SUNDAY SHOULD
BE THE WARMEST DAY SINCE JUNE 2ND ACROSS THE AREA AS ADDITIONAL
WARMING ALOFT OCCURS WITH MID TO UPPER 80S EXPECTED FOR MUCH OF THE
REGION.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
FLAT BROAD UPPER RIDGING SHOULD SET UP OVER EASTERN NORTH AMERICA
WITH SMALL PIECES OF UPPER LEVEL ENERGY TRACKING AROUND THE NORTHERN
PERIPHERY OF THE RIDGE MONDAY THROUGH TUESDAY NIGHT. THESE LITTLE
PIECES OF UPPER ENERGY SHOULD ENHANCE THE THREAT OF SHOWERS/TSTMS
EACH AFTN/EVENING AND HAVE FORECAST 30 TO 40 PERCENT POPS EACH
AFTN/EVENING...AND 20 TO 30 PERCENT POPS DURING THE OVERNIGHT AND
MORNING HOURS. FOR SUNDAY NIGHT HAVE FORECAST DRY CONDITIONS.
ALTHOUGH NOT AS IMPRESSIVE AS LAST NIGHT...THE GFS/ECMWF STILL SHOW
A DEEPENING UPPER LEVEL TROF WILL MOVE INTO THE REGION BY WEDNESDAY
AFTN WITH AN EVEN GREATER THREAT FOR SHOWERS/TSTMS WED AFTN THROUGH
THURSDAY. FOR EACH AFTN/EVENING DURING THIS PERIOD HAVE FORECAST 40
TO 50 PERCENT POPS...AND 30 TO 40 PERCENT DURING THE OVERNIGHT
AND EARLY MORNING HOURS.
IT WILL BE VERY WARM OR HOT EARLY IN THE LONG TERM PERIOD...WITH A
BIT OF A COOL DOWN WEDNESDAY AND THURSDAY AS THE UPPER LEVEL TROF
MOVES INTO THE REGION. IT WILL BE HUMID DURING THE ENTIRE PERIOD
WITH DEWPOINTS GENERALLY IN THE 60S.
HIGHS MONDAY AND TUESDAY WILL BE IN THE 80S TO AROUND 90...THEN
UPPER 70S AND 80S WEDNESDAY...AND MID 70S TO LOWER 80S THURSDAY.
LOWS WILL GENERALLY BE IN THE UPPER 50S AND 60S SUNDAY NIGHT THROUGH
WEDNESDAY NIGHT.
&&
.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
ALTHOUGH NOT OCCURRING YET...HAVE INCLUDED TEMPO GROUPS FOR IFR FOG
AT KGFL/KPSF SINCE CLEAR SKIES AND CALM WINDS WILL CONTINUE THROUGH
AFTER SUNRISE. OTHER THAN THE POSSIBLE IFR AT KGFL/KPSF...EXPECT VFR
CONDITIONS AT ALL THE TAF SITES (KALB/KPOU/KGFL/KPSF) THROUGH THE
TAF PERIOD ENDING AT 06Z SATURDAY. WITH HIGH PRESSURE OVER THE
REGION CONDITIONS WILL BE MAINLY P6SM SCT250 WITH A FEW CUMULUS
CLOUDS THIS AFTERNOON.
MAINLY OR LIGHT SOUTH WINDS THROUGH A FEW HOURS AFTER SUNRISE...THEN
SOUTH TO SOUTHWEST WINDS AT LESS THAN 8 KTS DURING THE REST OF
FRIDAY...THEN CALM WINDS AGAIN FRIDAY NIGHT.
OUTLOOK...
LATE FRI NITE...MAINLY VFR. NO SIG WX.
SAT...MAINLY VFR. SLGT CHC -TSRA/-SHRA.
SUN-TUE...MAINLY VFR. CHC -TSRA/-SHRA.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS CONTINUE DUE TO THE PAST SEVERAL WEEKS OF
WET WEATHER.
HIGH PRESSURE WILL MOVE OFF THE EAST COAST TODAY INTO THE WEEKEND.
ISOLATED TO SCATTERED SHOWERS OR THUNDERSTORMS ARE POSSIBLE FROM
THIS AFTERNOON AFTERNOON THROUGH THE WEEKEND...ALONG WITH A GRADUAL
WARMING TREND. DEW FORMATION SHOULD OCCUR EACH NIGHT WITH THE RISING
LEVELS OF HUMIDITY.
&&
.HYDROLOGY...
FLOWS REMAIN ABOVE NORMAL ACROSS THE HYDRO SERVICE AREA.
FROM TODAY INTO EARLY NEXT WEEK...THERE MAY ISOLATED TO SCATTERED
SHOWERS OR THUNDERSTORMS...BUT WIDESPREAD RAINFALL IS NOT
ANTICIPATED AT THIS TIME...AND NOT ALL LOCATIONS WILL SEE RAINFALL.
THUS...RIVER LEVELS ARE EXPECTED TO CONTINUE TO GRADUALLY RECEDE
DURING THIS TIME.
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...JPV
NEAR TERM...JPV
SHORT TERM...JPV
LONG TERM...GJM
AVIATION...GJM
FIRE WEATHER...FRUGIS/JPV
HYDROLOGY...FRUGIS/JPV
AREA FORECAST DISCUSSION
NWS MIAMI FL
251 AM EDT FRI JUN 21 2013
SHORT TERM (TODAY THROUGH SUNDAY)...
NOT MUCH HAS CHANGED FROM EARLIER THINKING. DEEP LAYER RIDGE HAS
BECOME ESTABLISHED ACROSS THE FLORIDA PENINSULA AND IT WILL SHIFT
JUST SLIGHTLY NORTH TODAY AS A TROPICAL WAVE APPROACHES FROM THE
BAHAMAS. DRIER ALOFT AHEAD OF THE WAVE WILL MOVE OVER SOUTH
FLORIDA TODAY WITH PWAT DROPPING TO AROUND 1.5 INCHES.OR SLIGHTLY
LESS AND THIS SEEN ON SATELLITE DERIVED TOTAL PWAT WITH GLOBAL
MODELS ALSO IN GOOD AGREEMENT. THE HRRR IS SHOWING ONLY A FEW SHRA
ALONG THE EAST COAST EARLY THIS MORNING AND THEN DEVELOPS
CONVECTION FROM NEAR BELLE GLADES TO NAPLES AREA AND POINTS NORTH
AFTER 18Z SO THIS ALL SEEMS REASONABLE. THE WAVE IS CURRENTLY
LOCATED ACROSS THE EASTERN BAHAMAS AND EXTENDING SOUTH INTO THE
CARIBBEAN THROUGH THE DOMINICAN REPUBLIC AND HAS LOST MUCH OF ITS
CONVECTION. THE GLOBAL MODELS ARE NOT TOO TERRIBLY IMPRESSED WITH
IT BUT DO INCREASE THE MOISTURE ACROSS SOUTH FLORIDA BY EARLY
SATURDAY SO THERE SHOULD BE AN INCREASE IN SHOWER ACTIVITY OVER
THE ATLANTIC OFF THE SOUTHEAST COAST LATE TONIGHT AND THEN THESE
MOVING ONSHORE DURING THE DAY. THE WAVE WILL CONTINUE WESTWARD BY
SUNDAY WITH DRIER AIR AGAIN MOVING IN ALOFT LATE IN THE WEEKEND
FOR A DECREASE IN CONVECTION WITH THE GREATEST CONCENTRATION NEAR
THE SOUTHWEST COAST.
.LONG TERM (SUNDAY NIGHT THROUGH THURSDAY)...
A DEEP EASTERLY FLOW WILL BE ESTABLISHED ALL OF NEXT WEEK WITH
FORECAST SOUNDINGS SHOWING PWAT AT AROUND 1.6-1.7 INCHES SO
SLIGHTLY BELOW THE LATE JUNE AVERAGE WHICH IS ABOUT 1.75 INCHES.
STEERING FLOW WILL BE SUCH THAT THE BEST CHANCES FOR RAINFALL WILL
BE ALONG THE ATLANTIC COAST DURING THE LATE NIGHT AND EARLY
MORNING SHIFTING TO THE INTERIOR AND GULF COAST DURING THE
AFTERNOON AND EVENINGS.
&&
.AVIATION...
MODELS INDICATE A DRIER AND QUIETER WEATHER DAY TODAY. THE ONLY
AREA HAS ANY PRECIPITATION REFLECTED IN THE TAFS AT THIS TIME IS
KAPF, WITH A VCSH. EVEN SO, THERE IS A SLIGHT CHANCE OF A
THUNDERSTORM ACROSS MOST OF SOUTH FLORIDA, WITH A SLIGHTLY HIGHER
CHANCE OF ONE FOR KAPF. OTHERWISE, A PARTLY CLOUDY DAY, WITH
SOUTHEASTERLY WINDS BETWEEN 10 AND 15 KTS. WINDS SHOULD BECOME
MORE EASTERLY IN THE EVENING AND DROP TO 5 TO 10 KTS.
&&
.MARINE...
MARINE CONDITIONS WILL REMAIN BELOW ADVISORY CRITERIA BUT THERE
COULD BE AN INCREASE IN THE SOUTHEAST WIND OVER THE WEEKEND TO 15
KNOTS OR A LITTLE HIGHER. BUT SEAS WILL GENERALLY BE 4 FEET OR
LESS THROUGH THE PERIOD.
&&
.FIRE WEATHER...
NO PROBLEMS OR CONCERNS WITH AMPLE LOW LEVEL MOISTURE THROUGH THE
WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 88 78 87 77 / 20 20 40 30
FORT LAUDERDALE 87 78 87 78 / 20 20 40 30
MIAMI 89 78 88 77 / 20 20 40 30
NAPLES 92 73 93 74 / 30 20 40 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...30/KOB
AVIATION/RADAR...13/SI
AREA FORECAST DISCUSSION
NWS POCATELLO ID
254 AM MDT FRI JUN 21 2013
.DISCUSSION...UPPER LOW CONTINUES TO SPIN OVER WESTERN MONTANA AND
THE IDAHO PANHANDLE THIS MORNING AND IS SEEN SPINNING UP A COUPLE
OF VORT LOBES THAT WILL MOVE THROUGH TODAY AND TONIGHT. THE FIRST
IS CURRENTLY PRODUCING SHOWERS OVER SOUTHWEST IDAHO. HRRR PROJECTS
THIS WAVE OF ENERGY TO MOVE THROUGH THE SNAKE PLAIN THIS MORNING
AND IN THE UPPER SNAKE HIGHLANDS AROUND NOON. NOT EXPECTING MUCH
TO REACH THE GROUND...BUT HAVE INCLUDED SLIGHT CHANCE POPS OVER
THE SOUTHERN HIGHLANDS THIS MORNING. THE SECOND LOBE WILL SWING
AROUND ON SATURDAY MORNING IMPACTING MAINLY THE CENTRAL IDAHO
MOUNTAINS...BUT THE SNAKE PLAIN MAY SEE INCREASED WINDS AS THE
TROUGH SWINGS THROUGH.
MOVING AHEAD TO SATURDAY NIGHT AND SUNDAY...UPPER RIDGING WILL MOVE
ACROSS THE AREA RESULTING IN WARM AND DRY WEATHER. LONG-TERM MODELS
ARE PROJECTING ANOTHER STRONG PACIFIC TROUGH TO ADVANCE INTO THE
PACIFIC NORTHWEST MONDAY. HIGHER POPS THEN ARE EXPECTED FOR MONDAY
NIGHT AND TUESDAY AS THE HIGHER PWATS ARE BROUGHT IN WITH A 110+ KT
JET STREAK EDGING INTO NORTHERN CALIFORNIA. SHOWERS WILL BEGIN TO
WRAP UP AROUND TUESDAY NIGHT AND WEDNESDAY AS AN UPPER HIGH BEGINS
BUILDING INTO THE WEST BRINGING MUCH WARMER TEMPERATURES IN THE
LATTER HALF OF NEXT WEEK WITH HIGHS BACK UP IN THE 90S. HINSBERGER
&&
.AVIATION...A LOW PRESSURE SYSTEM ADVANCING EAST ALONG THE NRN
NEVADA BORDER EARLY THIS MORNING WILL LIFT NE INTO MONTANA THIS
AFTERNOON WITH SCT SHOWERS AND VFR CIGS SPREADING ACROSS THE
REGION THIS MORNING. PARTIAL CLEARING IS EXPECTED OVERNIGHT AS THE
WAVE LIFTS FURTHER NE ACROSS MONTANA AND THE PRIMARY LOW REMAINS
POSITIONED OVER THE IDAHO PANHANDLE. HUSTON
&&
.FIRE WEATHER...EARLY MORNING SATELLITE IMAGERY SHOWED A LOW
POSITIONED OVER THE IDAHO PANHANDLE AS A SECONDARY DISTURBANCE
ROTATED THROUGH THE BASE OF THE LOW WORKING EAST ALONG THE NRN
NEVADA BORDER WITH AN ASSOCIATED BAND OF SHOWERS ADVANCING EAST
AHEAD OF THE DISTURBANCE. MODEL SOLUTIONS SUGGEST THAT THE SECONDARY
WAVE WILL ROTATE THROUGH SE IDAHO THIS MORNING AND INTO SW MONTANA
THIS AFTERNOON WITH ATTENDING SHOWERS FAVORED ACROSS THE
SALMON-CHALLIS AND TARGHEE DISTRICTS TODAY AND TO A LESSER EXTENT
THE SRN AND ERN DISTRICTS. TONIGHT AND SATURDAY...THE MAIN LOW WILL
BEGIN TO SHIFT EAST INTO SW MONTANA AS AN INCREASINGLY DRIER NW FLOW
OVERSPREADS THE REGION SATURDAY AFTERNOON AHEAD OF THE NEXT PACIFIC
STORM SYSTEM ADVANCING INTO NW COASTAL WATERS. DISTURBANCES EJECTING
FROM THIS SYSTEM ARE EXPECTED TO ROTATE THROUGH THE NW STATES EARLY
NEXT WEEK PROVIDING UNSETTLE/SHOWERY CONDITIONS THROUGH AT LEAST
TUESDAY. FOR THE LATTER HALF OF THE WEEK...THERE APPEARS TO BE
GOOD MODEL CONSENSUS THAT A STRONG UPPER RIDGE WILL BUILD ACROSS THE
WEST BRINGING WARMER THAN NORMAL TEMPERATURES BACK TO THE REGION.
HUSTON
&&
.PIH WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
324 PM CDT FRI JUN 21 2013
.DISCUSSION...
329 AM CDT
THE MAIN FORECAST CHALLENGE FOR THE SHORT TERM WILL BE THE EVOLUTION
OF THE MCS OVER THE UPPER MS VALLEY TODAY. THIS COULD BE FOLLOWED
BY ADDITIONAL STORM CLUSTERS THROUGH SATURDAY...AND AGAIN MONDAY
THROUGH WEDNESDAY. ALSO THE BUILDING HEAT AND HUMIDITY THROUGH
THE MIDDLE OF NEXT WEEK.
IN THE SHORT TERM A NARROW BAND OF SHOWERS AND WEAK THUNDERSTORMS
EXTENDS FROM WESTERN WI TO THE IL/IA BORDER. THIS ACTIVITY OCCURRING
ALONG AN AXIS OF HIGHER LOW LEVEL MOISTURE AND THE EASTERN EDGE OF
THE LOW LEVEL JET. EXPECT THIS ACTIVITY TO WEAKEN AND DIE EARLY THIS
MORNING AS IT MOVES INTO DRIER AND MORE STABLE ATMOSPHERE. HAVE SOME
LOW POPS FOR FAR WESTERN COUNTIES THROUGH MID MORNING. MEANWHILE
VERY ACTIVE MCS OVER MN DIVING SOUTHEAST. THIS ACTIVITY SHOULD BE
ON A DIURNALLY WEAKENING TREND LATER THIS MORNING. MEAN MID AND
UPPER LEVEL WINDS ARE WESTERLY WITH FLAT RIDGE ACROSS THE UPPER MS
VALLEY AND GREAT LAKES...WHICH MIGHT SUGGEST THIS WILL REMAIN
MAINLY NORTH OVER WISCONSIN...BUT ACTIVITY IS DROPPING SOUTHEAST
AS CONVECTION BACK BUILDS INTO LOW LEVEL JET. IF IT HOLDS
TOGETHER ON ITS PRESENT COURSE...IT WILL BE APPROACHING NORTHWEST
AND NORTH CENTRAL IL BY LATE MORNING. HRRR SEEMS TO BE THE MOST
AGGRESSIVE OF THE SHORT TERM GUIDANCE IN BRINGING PRECIP INTO
NORTHERN IL TODAY. DEEP LAYER SHEAR WILL BE LACKING THIS FAR
SOUTH BUT WITH BUILDING HEAT AND SURFACE DEW POINTS CLIMBING INTO
THE MID AND UPPER 60S...THERE MAY BE SUFFICIENT LOW LEVEL
INSTABILITY FOR STORMS TO CONTINUE SOUTHEASTWARD INTO IL. HAVE
MAINTAINED 30-40 PERCENT POPS MAINLY FOR NORTHERN COUPLE OF TIERS
OF COUNTIES. SPC HAS MUCH OF NORTHERN IL IN SLIGHT RISK FOR WIND
AND HAIL THREAT. THE ASSOCIATED CIRRUS SHIELD MAY ALSO IMPACT
TEMPERATURES. THEREFORE HAVE LOWERED MAX TEMPS ACROSS THE FAR NORTH
DOWN A COUPLE DEGREES TO THE MID 80S WHILE KEEPING MAX TEMPS IN
UPPER 80S TO NEAR 90 FURTHER SOUTH. EXPECT SOUTH WINDS TO BE
SUFFICIENTLY STRONG TO PREVENT A LAKE BREEZE. ALTHOUGH WITH SOUTH
TO SLIGHTLY EAST OF SOUTH WINDS...A WEAK LAKE BREEZE MAY DRIFT
ONSHORE ACROSS NORTHERN COOK AND LAKE COUNTY IN THIS AFTERNOON.
ANOTHER MCS MAY DEVELOP AND MOVE THROUGH THE NORTHERN PART OF THE
FORECAST AREA AGAIN SATURDAY AS A SERIES OF WEAK WAVES MOVES THROUGH
THE RING OF FIRE ACROSS THE GREAT LAKES. BUT LOW CONFIDENCE THIS FAR
OUT. THE GENERAL TREND OF THE MODELS IS TO SLOWLY BUILD THE RIDGE
INTO THE WESTERN GREAT LAKES OVER THE WEEKEND. THEREFORE HAVE JUST
LOW CHANCE POPS FOR SATURDAY AND A DRY FORECAST FOR SUNDAY. MONDAY
THROUGH WEDNESDAY A SERIES OF WAVES SUPPRESSES THE RIDGE...WHICH
EVENTUALLY RE-ESTABLISHES ITSELF OVER THE WESTERN US. BY THE END
OF THE WEEK MODELS IN DECENT AGREEMENT IN DEVELOPING AN UPPER LOW
OVER THE GREAT LAKES.
MAX TEMPERATURES EXPECTED TO BE IN THE UPPER 80S TO AROUND 90 TODAY
THROUGH WEDNESDAY...WITH DEW POINTS IN THE UPPER 60S TO AROUND 70.
THIS PRODUCES HEAT INDEX VALUES IN MID TO UPPER 90S. THIS IS
BELOW LOCAL HEAT ADVISORY THRESHOLDS. HOWEVER SEEING AS THIS IS
THE FIRST HEAT WAVE OF THE SUMMER AND IT MAY PERSIST FOR SEVERAL
DAYS. A HEAT ADVISORY MAY NEED TO BE CONSIDERED BY EARLY TO MID
WEEK. ANY THUNDERSTORMS AND ASSOCIATED CLOUD COVER/OUTFLOW
BOUNDARIES MAY TEMPORARILY COOL THINGS DOWN AND IMPACT ANY FUTURE
DECISIONS ON HEAT HEADLINES.
PATTERN LOOKS TO BECOME MUCH COOLER NEXT WEEKEND.
ALLSOPP
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* VARIABLE WIND DIRECTION BETWEEN SW AND SE NEXT FEW HOURS
BECOMING MORE SOUTHEAST.
MDB
//DISCUSSION...UPDATED 20Z...
CONVECTION NOW TO THE SOUTHEAST OF THE TERMINALS WITH SOME
LINGERING LIGHT RAIN AND EMBEDDED THUNDER MOVING OUT OF THE AREA.
WINDS HAVE BEEN SOMEWHAT ERRATIC BUT THE TREND LOOKS TO BE MORE
SOUTHEASTERLY BY LATE AFTERNOON. GUSTS LOOK TO COME UP AND MAY
NEED TO BUMP THEM UP FOR A BRIEF TIME TOWARD 21-22Z. BEYOND THAT
PRECIP THREAT LOOKS MINIMAL THROUGH THE EVENING BUT WILL NEED TO
WATCH CONVECTION CURRENTLY OVER EASTERN SOUTH DAKOTA WHICH MAY
TRACK NEAR THE AREA LATE TONIGHT OR SATURDAY MORNING.
MDB
FROM 18Z...
LINE OF STORMS CONTINUES TO MOVE EASTWARD WITH OUTFLOW/WIND SHIFT
OUT AHEAD OF IT. OUTFLOW WILL REACH MDW SHORTLY AND GYY BY
1830-19Z OR SO. ARRIVAL OF STORMS AT GYY MAY NEED TO BE DELAYED
SLIGHTLY AS THE EASTWARD PROGRESS HAS SLOWED SLIGHTLY BUT IT DOES
LOOK AS THOUGH THEY WILL REACH THE FIELD. OTHERWISE RFD LOOKS TO
GET BACK INTO LIGHTER RAIN WITH SOME EMBEDDED THUNDER WHICH DOES
LOOK TO AFFECT THE CHICAGO AREA TERMINALS THROUGH MID AFTERNOON
BEHIND THE MAIN LINE. WINDS WILL BE A CHALLENGE WITH A SHIFT TO
NORTHWEST WITH THE OUTFLOW. BASED ON LATEST TRENDS...EXPECT THE
NORTHERLY DIRECTION TO CONTINUE IMMEDIATELY BEHIND THE LINE WITH
REDUCED SPEEDS BEFORE DIRECTION BECOMES VARIABLE BETWEEN NORTH AND
EAST. WINDS WILL EVENTUALLY BECOME SOUTHERLY BUT HAVE LOW
CONFIDENCE IN TIMING. ONCE THE PRECIP ENDS THIS AFTERNOON
ADDITIONAL DEVELOPMENT LOOKS TO BE FOCUSED SOUTH OF THE TERMINALS.
LOW CHANCES FOR SHRA/TSRA CONTINUE OVERNIGHT BUT AT THIS POINT
CONFIDENCE IN OCCURRENCE AND COVERAGE IS LOW SO WILL LEAVE MENTION
OUT FOR NOW. UPPER RIDGING WILL BE BUILDING IN SATURDAY SO
SHRA/TSRA THREAT WILL DIMINISH THROUGH THE DAY. SOUTHWESTERLY
WINDS ARE EXPECTED SATURDAY WITH GUSTS TO AROUND 20 KT EXPECTED BY
MIDDAY.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM CONFIDENCE IN WIND TRENDS THROUGH THE EVENING.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...VFR.
SUNDAY...MAINLY VFR. CHC THUNDERSTORMS LATE.
MONDAY THROUGH THURSDAY...PERIODIC CHANCES FOR THUNDERSTORMS.
OTHERWISE VFR.
BEACHLER
&&
.MARINE...
323 PM CDT
S TO SW MODERATE TO OCCASIONALLY FRESH BREEZES WILL PREVAIL ON LAKE
MI FOR THE NEXT SEVERAL DAYS AS A BROAD AREA OF HIGH PRESSURE WILL
REMAIN CENTERED OVER THE WESTERN ATLANTIC...EXTENDING BACK TO THE
WEST ACROSS THE SOUTHEASTERN U.S. WHILE AN AREA OF LOW PRESSURE
DRIFTS VERY SLOWLY EASTWARD ACROSS THE PLAINS.
THIS PREVAILING S TO SW WIND WILL CONTINUE TO SPREAD VERY WARM AND
MOIST AIR ACROSS THE REGION TONIGHT...AND MAINTAIN IT THROUGH THE
WEEKEND AND INTO NEXT WEEK. AS THIS WARM MOIST AIR MOVES OUT OVER
THE COOL OPEN WATERS OF LAKE MI FOG WILL FORM AND MAY BECOME DENSE
AT TIMES.
DISTURBANCES MOVING E FROM THE NORTHERN PLAINS AND ACROSS THE UPPER
GREAT LAKES DURING THE NEXT SEVERAL DAYS WILL MAINTAIN PERIODIC
CHANCES FOR SHOWERS AND THUNDERSTORMS.
TRS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
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AREA FORECAST DISCUSSION
NWS LINCOLN IL
305 PM CDT FRI JUN 21 2013
.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.
SHIMON
&&
.AVIATION...
ISSUED 1240 PM CDT FRI JUN 21 2013
CONVECTION TO OUR NORTH CONTINUES TO SLOWLY SINK SOUTHEAST EARLY
THIS AFTERNOON. LEADING EDGE OF COLD POOL/OUTFLOW BOUNDARY CLEARLY EVIDENT
ON KDVN REFLECTIVITY AND IS SHIFTING SOUTH AROUND 20 KTS AND IS NOW
PUSHING INTO NORTHERN KNOX AND STARK COUNTIES. IF THIS MAINTAINS
TRENDS WOULD PASS THROUGH KPIA JUST BEFORE 19Z AND KBMI AT 20Z.
BEHIND THIS BOUNDARY WINDS SHIFT NORTH GUSTING AROUND 20 KTS. LIFT
OFF THE BOUNDARY IS PRODUCING SCATTERED TSRA BEHIND IT SO HAVE
INCLUDED VCTS AFTER PASSAGE FOR KPIA/KBMI WITH A TEMP PERIOD AT
KPIA WHERE HAVE HIGHER CONFIDENCE. BOUNDARY SHOULD EVENTUALLY SLOW AND
STALL AS MAIN CONVECTIVE BATCH TO THE NORTH SHIFTS EAST...AND
10-20 KT SOUTHWEST SYNOPTIC FLOW PROVIDES RESISTANCE. SO HAVE KEPT
THIS ACTIVITY OUT OF THE TERMINALS FARTHER SOUTH/EAST. GUSTY S/SW
WINDS WILL DROP BELOW 10 KTS AFTER SUNSET...THEN PICK UP AGAIN
AFTER 14Z/SAT.
25
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
300 PM CDT FRI JUN 21 2013
.DISCUSSION...
329 AM CDT
THE MAIN FORECAST CHALLENGE FOR THE SHORT TERM WILL BE THE EVOLUTION
OF THE MCS OVER THE UPPER MS VALLEY TODAY. THIS COULD BE FOLLOWED
BY ADDITIONAL STORM CLUSTERS THROUGH SATURDAY...AND AGAIN MONDAY
THROUGH WEDNESDAY. ALSO THE BUILDING HEAT AND HUMIDITY THROUGH
THE MIDDLE OF NEXT WEEK.
IN THE SHORT TERM A NARROW BAND OF SHOWERS AND WEAK THUNDERSTORMS
EXTENDS FROM WESTERN WI TO THE IL/IA BORDER. THIS ACTIVITY OCCURRING
ALONG AN AXIS OF HIGHER LOW LEVEL MOISTURE AND THE EASTERN EDGE OF
THE LOW LEVEL JET. EXPECT THIS ACTIVITY TO WEAKEN AND DIE EARLY THIS
MORNING AS IT MOVES INTO DRIER AND MORE STABLE ATMOSPHERE. HAVE SOME
LOW POPS FOR FAR WESTERN COUNTIES THROUGH MID MORNING. MEANWHILE
VERY ACTIVE MCS OVER MN DIVING SOUTHEAST. THIS ACTIVITY SHOULD BE
ON A DIURNALLY WEAKENING TREND LATER THIS MORNING. MEAN MID AND
UPPER LEVEL WINDS ARE WESTERLY WITH FLAT RIDGE ACROSS THE UPPER MS
VALLEY AND GREAT LAKES...WHICH MIGHT SUGGEST THIS WILL REMAIN
MAINLY NORTH OVER WISCONSIN...BUT ACTIVITY IS DROPPING SOUTHEAST
AS CONVECTION BACK BUILDS INTO LOW LEVEL JET. IF IT HOLDS
TOGETHER ON ITS PRESENT COURSE...IT WILL BE APPROACHING NORTHWEST
AND NORTH CENTRAL IL BY LATE MORNING. HRRR SEEMS TO BE THE MOST
AGGRESSIVE OF THE SHORT TERM GUIDANCE IN BRINGING PRECIP INTO
NORTHERN IL TODAY. DEEP LAYER SHEAR WILL BE LACKING THIS FAR
SOUTH BUT WITH BUILDING HEAT AND SURFACE DEW POINTS CLIMBING INTO
THE MID AND UPPER 60S...THERE MAY BE SUFFICIENT LOW LEVEL
INSTABILITY FOR STORMS TO CONTINUE SOUTHEASTWARD INTO IL. HAVE
MAINTAINED 30-40 PERCENT POPS MAINLY FOR NORTHERN COUPLE OF TIERS
OF COUNTIES. SPC HAS MUCH OF NORTHERN IL IN SLIGHT RISK FOR WIND
AND HAIL THREAT. THE ASSOCIATED CIRRUS SHIELD MAY ALSO IMPACT
TEMPERATURES. THEREFORE HAVE LOWERED MAX TEMPS ACROSS THE FAR NORTH
DOWN A COUPLE DEGREES TO THE MID 80S WHILE KEEPING MAX TEMPS IN
UPPER 80S TO NEAR 90 FURTHER SOUTH. EXPECT SOUTH WINDS TO BE
SUFFICIENTLY STRONG TO PREVENT A LAKE BREEZE. ALTHOUGH WITH SOUTH
TO SLIGHTLY EAST OF SOUTH WINDS...A WEAK LAKE BREEZE MAY DRIFT
ONSHORE ACROSS NORTHERN COOK AND LAKE COUNTY IN THIS AFTERNOON.
ANOTHER MCS MAY DEVELOP AND MOVE THROUGH THE NORTHERN PART OF THE
FORECAST AREA AGAIN SATURDAY AS A SERIES OF WEAK WAVES MOVES THROUGH
THE RING OF FIRE ACROSS THE GREAT LAKES. BUT LOW CONFIDENCE THIS FAR
OUT. THE GENERAL TREND OF THE MODELS IS TO SLOWLY BUILD THE RIDGE
INTO THE WESTERN GREAT LAKES OVER THE WEEKEND. THEREFORE HAVE JUST
LOW CHANCE POPS FOR SATURDAY AND A DRY FORECAST FOR SUNDAY. MONDAY
THROUGH WEDNESDAY A SERIES OF WAVES SUPPRESSES THE RIDGE...WHICH
EVENTUALLY RE-ESTABLISHES ITSELF OVER THE WESTERN US. BY THE END
OF THE WEEK MODELS IN DECENT AGREEMENT IN DEVELOPING AN UPPER LOW
OVER THE GREAT LAKES.
MAX TEMPERATURES EXPECTED TO BE IN THE UPPER 80S TO AROUND 90 TODAY
THROUGH WEDNESDAY...WITH DEW POINTS IN THE UPPER 60S TO AROUND 70.
THIS PRODUCES HEAT INDEX VALUES IN MID TO UPPER 90S. THIS IS
BELOW LOCAL HEAT ADVISORY THRESHOLDS. HOWEVER SEEING AS THIS IS
THE FIRST HEAT WAVE OF THE SUMMER AND IT MAY PERSIST FOR SEVERAL
DAYS. A HEAT ADVISORY MAY NEED TO BE CONSIDERED BY EARLY TO MID
WEEK. ANY THUNDERSTORMS AND ASSOCIATED CLOUD COVER/OUTFLOW
BOUNDARIES MAY TEMPORARILY COOL THINGS DOWN AND IMPACT ANY FUTURE
DECISIONS ON HEAT HEADLINES.
PATTERN LOOKS TO BECOME MUCH COOLER NEXT WEEKEND.
ALLSOPP
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* VARIABLE WIND DIRECTION BETWEEN SW AND SE NEXT FEW HOURS
BECOMING MORE SOUTHEAST.
MDB
//DISCUSSION...UPDATED 20Z...
CONVECTION NOW TO THE SOUTHEAST OF THE TERMINALS WITH SOME
LINGERING LIGHT RAIN AND EMBEDDED THUNDER MOVING OUT OF THE AREA.
WINDS HAVE BEEN SOMEWHAT ERRATIC BUT THE TREND LOOKS TO BE MORE
SOUTHEASTERLY BY LATE AFTERNOON. GUSTS LOOK TO COME UP AND MAY
NEED TO BUMP THEM UP FOR A BRIEF TIME TOWARD 21-22Z. BEYOND THAT
PRECIP THREAT LOOKS MINIMAL THROUGH THE EVENING BUT WILL NEED TO
WATCH CONVECTION CURRENTLY OVER EASTERN SOUTH DAKOTA WHICH MAY
TRACK NEAR THE AREA LATE TONIGHT OR SATURDAY MORNING.
MDB
FROM 18Z...
LINE OF STORMS CONTINUES TO MOVE EASTWARD WITH OUTFLOW/WIND SHIFT
OUT AHEAD OF IT. OUTFLOW WILL REACH MDW SHORTLY AND GYY BY
1830-19Z OR SO. ARRIVAL OF STORMS AT GYY MAY NEED TO BE DELAYED
SLIGHTLY AS THE EASTWARD PROGRESS HAS SLOWED SLIGHTLY BUT IT DOES
LOOK AS THOUGH THEY WILL REACH THE FIELD. OTHERWISE RFD LOOKS TO
GET BACK INTO LIGHTER RAIN WITH SOME EMBEDDED THUNDER WHICH DOES
LOOK TO AFFECT THE CHICAGO AREA TERMINALS THROUGH MID AFTERNOON
BEHIND THE MAIN LINE. WINDS WILL BE A CHALLENGE WITH A SHIFT TO
NORTHWEST WITH THE OUTFLOW. BASED ON LATEST TRENDS...EXPECT THE
NORTHERLY DIRECTION TO CONTINUE IMMEDIATELY BEHIND THE LINE WITH
REDUCED SPEEDS BEFORE DIRECTION BECOMES VARIABLE BETWEEN NORTH AND
EAST. WINDS WILL EVENTUALLY BECOME SOUTHERLY BUT HAVE LOW
CONFIDENCE IN TIMING. ONCE THE PRECIP ENDS THIS AFTERNOON
ADDITIONAL DEVELOPMENT LOOKS TO BE FOCUSED SOUTH OF THE TERMINALS.
LOW CHANCES FOR SHRA/TSRA CONTINUE OVERNIGHT BUT AT THIS POINT
CONFIDENCE IN OCCURRENCE AND COVERAGE IS LOW SO WILL LEAVE MENTION
OUT FOR NOW. UPPER RIDGING WILL BE BUILDING IN SATURDAY SO
SHRA/TSRA THREAT WILL DIMINISH THROUGH THE DAY. SOUTHWESTERLY
WINDS ARE EXPECTED SATURDAY WITH GUSTS TO AROUND 20 KT EXPECTED BY
MIDDAY.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM CONFIDENCE IN WIND TRENDS THROUGH THE EVENING.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...VFR.
SUNDAY...MAINLY VFR. CHC THUNDERSTORMS LATE.
MONDAY THROUGH THURSDAY...PERIODIC CHANCES FOR THUNDERSTORMS.
OTHERWISE VFR.
BEACHLER
&&
.MARINE...
240 AM CDT
MAIN CONCERN FOR LAKE MICHIGAN WILL BE POTENTIAL FOR FOG
DEVELOPMENT AND TIMING...ALONG WITH CHANCES FOR THUNDERSTORMS. AT
THIS TIME THERE DOES NOT APPEAR TO BE ANY WIND/WAVE HAZARDS
EXPECTED IN THE NEXT SEVERAL DAYS.
HIGH PRESURE ANCHORED ACROSS THE WESTERN ATLANTIC OCEAN ALONG WITH
A BROAD LOW PRESSURE ANCHORED OVER THE CENTRAL PLAINS...WILL
MAINTAIN THE SOUTHERLY FLOW OVER THE LAKE. IN ADDITION VERY WARM
AIR WILL SLIDE OVER THE COOLER OPEN WATERS OF THE LAKE...AND HELP
TO KEEP WAVES FROM BUILDING TO LARGE. THE GRADIENT THIS AFTERNOON
DOES INCREASE WHICH MAY ALLOW WINDS TO INCREASE TO AROUND 20-25KT
FOR THE NORTHERN HALF OF THE LAKE...HOWEVER WAVES SHOULD ONLY
BUILD TO 2 TO 4 FT. AT TIMES WINDS MAY GUST TO 25 KT FURTHER SOUTH
THIS AFTERNOON. THUNDERSTORMS ARE FORECAST FOR THE NEXT SEVERAL
DAYS...HOWEVER THESE DO NOT APPEAR TO BE AN ALL DAY OR NIGHT
THING. BUT WINDS/WAVES WILL BE HIGHER IN AND AROUND ANY
THUNDERSTORMS THAT DO SLIDE ACROSS THE LAKE.
AS MENTIONED EARLIER ABOUT THE FOG DEVELOPMENT. IT DOES APPEAR
THAT WITH ENOUGH WIND THIS AFTERNOON FOG WILL HOLD OFF UNTIL
PERHAPS LATE TONIGHT OR POSSIBLY SATURDAY. A WARM FRONT WILL LIFT
NORTH OVER THE LAKE...WITH FOG DEVELOPMENT EXPECTED JUST AFTER
PASSAGE. THIS STILL APPEARS TO FAVOR THE NORTHERN PORTIONS OF THE
LAKE AND AT TIMES COULD BE DENSE. ONCE FOG DEVELOPS IT COULD
EASILY LINGER THROUGH EARLY NEXT WEEK AS THE WINDS ARE NOT
EXPECTED TO BE VERY STRONG.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
101 PM CDT FRI JUN 21 2013
.DISCUSSION...
329 AM CDT
THE MAIN FORECAST CHALLENGE FOR THE SHORT TERM WILL BE THE EVOLUTION
OF THE MCS OVER THE UPPER MS VALLEY TODAY. THIS COULD BE FOLLOWED
BY ADDITIONAL STORM CLUSTERS THROUGH SATURDAY...AND AGAIN MONDAY
THROUGH WEDNESDAY. ALSO THE BUILDING HEAT AND HUMIDITY THROUGH
THE MIDDLE OF NEXT WEEK.
IN THE SHORT TERM A NARROW BAND OF SHOWERS AND WEAK THUNDERSTORMS
EXTENDS FROM WESTERN WI TO THE IL/IA BORDER. THIS ACTIVITY OCCURRING
ALONG AN AXIS OF HIGHER LOW LEVEL MOISTURE AND THE EASTERN EDGE OF
THE LOW LEVEL JET. EXPECT THIS ACTIVITY TO WEAKEN AND DIE EARLY THIS
MORNING AS IT MOVES INTO DRIER AND MORE STABLE ATMOSPHERE. HAVE SOME
LOW POPS FOR FAR WESTERN COUNTIES THROUGH MID MORNING. MEANWHILE
VERY ACTIVE MCS OVER MN DIVING SOUTHEAST. THIS ACTIVITY SHOULD BE
ON A DIURNALLY WEAKENING TREND LATER THIS MORNING. MEAN MID AND
UPPER LEVEL WINDS ARE WESTERLY WITH FLAT RIDGE ACROSS THE UPPER MS
VALLEY AND GREAT LAKES...WHICH MIGHT SUGGEST THIS WILL REMAIN
MAINLY NORTH OVER WISCONSIN...BUT ACTIVITY IS DROPPING SOUTHEAST
AS CONVECTION BACK BUILDS INTO LOW LEVEL JET. IF IT HOLDS
TOGETHER ON ITS PRESENT COURSE...IT WILL BE APPROACHING NORTHWEST
AND NORTH CENTRAL IL BY LATE MORNING. HRRR SEEMS TO BE THE MOST
AGGRESSIVE OF THE SHORT TERM GUIDANCE IN BRINGING PRECIP INTO
NORTHERN IL TODAY. DEEP LAYER SHEAR WILL BE LACKING THIS FAR
SOUTH BUT WITH BUILDING HEAT AND SURFACE DEW POINTS CLIMBING INTO
THE MID AND UPPER 60S...THERE MAY BE SUFFICIENT LOW LEVEL
INSTABILITY FOR STORMS TO CONTINUE SOUTHEASTWARD INTO IL. HAVE
MAINTAINED 30-40 PERCENT POPS MAINLY FOR NORTHERN COUPLE OF TIERS
OF COUNTIES. SPC HAS MUCH OF NORTHERN IL IN SLIGHT RISK FOR WIND
AND HAIL THREAT. THE ASSOCIATED CIRRUS SHIELD MAY ALSO IMPACT
TEMPERATURES. THEREFORE HAVE LOWERED MAX TEMPS ACROSS THE FAR NORTH
DOWN A COUPLE DEGREES TO THE MID 80S WHILE KEEPING MAX TEMPS IN
UPPER 80S TO NEAR 90 FURTHER SOUTH. EXPECT SOUTH WINDS TO BE
SUFFICIENTLY STRONG TO PREVENT A LAKE BREEZE. ALTHOUGH WITH SOUTH
TO SLIGHTLY EAST OF SOUTH WINDS...A WEAK LAKE BREEZE MAY DRIFT
ONSHORE ACROSS NORTHERN COOK AND LAKE COUNTY IN THIS AFTERNOON.
ANOTHER MCS MAY DEVELOP AND MOVE THROUGH THE NORTHERN PART OF THE
FORECAST AREA AGAIN SATURDAY AS A SERIES OF WEAK WAVES MOVES THROUGH
THE RING OF FIRE ACROSS THE GREAT LAKES. BUT LOW CONFIDENCE THIS FAR
OUT. THE GENERAL TREND OF THE MODELS IS TO SLOWLY BUILD THE RIDGE
INTO THE WESTERN GREAT LAKES OVER THE WEEKEND. THEREFORE HAVE JUST
LOW CHANCE POPS FOR SATURDAY AND A DRY FORECAST FOR SUNDAY. MONDAY
THROUGH WEDNESDAY A SERIES OF WAVES SUPPRESSES THE RIDGE...WHICH
EVENTUALLY RE-ESTABLISHES ITSELF OVER THE WESTERN US. BY THE END
OF THE WEEK MODELS IN DECENT AGREEMENT IN DEVELOPING AN UPPER LOW
OVER THE GREAT LAKES.
MAX TEMPERATURES EXPECTED TO BE IN THE UPPER 80S TO AROUND 90 TODAY
THROUGH WEDNESDAY...WITH DEW POINTS IN THE UPPER 60S TO AROUND 70.
THIS PRODUCES HEAT INDEX VALUES IN MID TO UPPER 90S. THIS IS
BELOW LOCAL HEAT ADVISORY THRESHOLDS. HOWEVER SEEING AS THIS IS
THE FIRST HEAT WAVE OF THE SUMMER AND IT MAY PERSIST FOR SEVERAL
DAYS. A HEAT ADVISORY MAY NEED TO BE CONSIDERED BY EARLY TO MID
WEEK. ANY THUNDERSTORMS AND ASSOCIATED CLOUD COVER/OUTFLOW
BOUNDARIES MAY TEMPORARILY COOL THINGS DOWN AND IMPACT ANY FUTURE
DECISIONS ON HEAT HEADLINES.
PATTERN LOOKS TO BECOME MUCH COOLER NEXT WEEKEND.
ALLSOPP
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* TSRA CROSSING THE TERMINALS WITH IFR VSBY AND VERY HEAVY
RAINFALL.
* NORTH TO NORTHWEST WINDS GUSTY WITH STORMS THEN DIMINISHING AND
BECOMING VARIABLE FROM NORTH TO EAST...THEN EVENTUALLY BACK TO
SOUTHERLY MID AFTERNOON.
MDB
//DISCUSSION...UPDATED 18Z...
LINE OF STORMS CONTINUES TO MOVE EASTWARD WITH OUTFLOW/WIND SHIFT
OUT AHEAD OF IT. OUTFLOW WILL REACH MDW SHORTLY AND GYY BY
1830-19Z OR SO. ARRIVAL OF STORMS AT GYY MAY NEED TO BE DELAYED
SLIGHTLY AS THE EASTWARD PROGRESS HAS SLOWED SLIGHTLY BUT IT DOES
LOOK AS THOUGH THEY WILL REACH THE FIELD. OTHERWISE RFD LOOKS TO
GET BACK INTO LIGHTER RAIN WITH SOME EMBEDDED THUNDER WHICH DOES
LOOK TO AFFECT THE CHICAGO AREA TERMINALS THROUGH MID AFTERNOON
BEHIND THE MAIN LINE. WINDS WILL BE A CHALLENGE WITH A SHIFT TO
NORTHWEST WITH THE OUTFLOW. BASED ON LATEST TRENDS...EXPECT THE
NORTHERLY DIRECTION TO CONTINUE IMMEDIATELY BEHIND THE LINE WITH
REDUCED SPEEDS BEFORE DIRECTION BECOMES VARIABLE BETWEEN NORTH AND
EAST. WINDS WILL EVENTUALLY BECOME SOUTHERLY BUT HAVE LOW
CONFIDENCE IN TIMING. ONCE THE PRECIP ENDS THIS AFTERNOON
ADDITIONAL DEVELOPMENT LOOKS TO BE FOCUSED SOUTH OF THE TERMINALS.
LOW CHANCES FOR SHRA/TSRA CONTINUE OVERNIGHT BUT AT THIS POINT
CONFIDENCE IN OCCURRENCE AND COVERAGE IS LOW SO WILL LEAVE MENTION
OUT FOR NOW. UPPER RIDGING WILL BE BUILDING IN SATURDAY SO
SHRA/TSRA THREAT WILL DIMINISH THROUGH THE DAY. SOUTHWESTERLY
WINDS ARE EXPECTED SATURDAY WITH GUSTS TO AROUND 20 KT EXPECTED BY
MIDDAY.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE IN TSRA TRENDS BEFORE 19Z...MEDIUM CONFIDENCE IN
LINGERING LIGHT RAIN AND EMBEDDED TS THROUGH MID AFTERNOON. HIGH
CONFIDENCE IN PERIODIC IFR VSBY WITH MAIN LINE.
* HIGH CONFIDENCE IN NORTH TO NORTHWEST WINDS WITH STORMS...MEDIUM
CONFIDENCE IN DIMINISHING TREND AND VARIABILITY BETWEEN NORTH
AND EAST...THEN EVENTUALLY TURNING SOUTHERLY...LOW CONFIDENCE IN
TIMING.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...VFR.
SUNDAY...MAINLY VFR. CHC THUNDERSTORMS LATE.
MONDAY THROUGH THURSDAY...PERIODIC CHANCES FOR THUNDERSTORMS.
OTHERWISE VFR.
BEACHLER
&&
.MARINE...
240 AM CDT
MAIN CONCERN FOR LAKE MICHIGAN WILL BE POTENTIAL FOR FOG
DEVELOPMENT AND TIMING...ALONG WITH CHANCES FOR THUNDERSTORMS. AT
THIS TIME THERE DOES NOT APPEAR TO BE ANY WIND/WAVE HAZARDS
EXPECTED IN THE NEXT SEVERAL DAYS.
HIGH PRESURE ANCHORED ACROSS THE WESTERN ATLANTIC OCEAN ALONG WITH
A BROAD LOW PRESSURE ANCHORED OVER THE CENTRAL PLAINS...WILL
MAINTAIN THE SOUTHERLY FLOW OVER THE LAKE. IN ADDITION VERY WARM
AIR WILL SLIDE OVER THE COOLER OPEN WATERS OF THE LAKE...AND HELP
TO KEEP WAVES FROM BUILDING TO LARGE. THE GRADIENT THIS AFTERNOON
DOES INCREASE WHICH MAY ALLOW WINDS TO INCREASE TO AROUND 20-25KT
FOR THE NORTHERN HALF OF THE LAKE...HOWEVER WAVES SHOULD ONLY
BUILD TO 2 TO 4 FT. AT TIMES WINDS MAY GUST TO 25 KT FURTHER SOUTH
THIS AFTERNOON. THUNDERSTORMS ARE FORECAST FOR THE NEXT SEVERAL
DAYS...HOWEVER THESE DO NOT APPEAR TO BE AN ALL DAY OR NIGHT
THING. BUT WINDS/WAVES WILL BE HIGHER IN AND AROUND ANY
THUNDERSTORMS THAT DO SLIDE ACROSS THE LAKE.
AS MENTIONED EARLIER ABOUT THE FOG DEVELOPMENT. IT DOES APPEAR
THAT WITH ENOUGH WIND THIS AFTERNOON FOG WILL HOLD OFF UNTIL
PERHAPS LATE TONIGHT OR POSSIBLY SATURDAY. A WARM FRONT WILL LIFT
NORTH OVER THE LAKE...WITH FOG DEVELOPMENT EXPECTED JUST AFTER
PASSAGE. THIS STILL APPEARS TO FAVOR THE NORTHERN PORTIONS OF THE
LAKE AND AT TIMES COULD BE DENSE. ONCE FOG DEVELOPS IT COULD
EASILY LINGER THROUGH EARLY NEXT WEEK AS THE WINDS ARE NOT
EXPECTED TO BE VERY STRONG.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS LINCOLN IL
1240 PM CDT FRI JUN 21 2013
.DISCUSSION...
ISSUED 1039 AM CDT FRI JUN 21 2013
SEVERE CONVECTIVE COMPLEX TO OUR NORTH MAIN ISSUE. THIS HAS BEEN
MAINTAINED BY A 40-45 KT SW 925 MB LOW LEVEL JET EVIDENT ON AREA
VWP/S AND A SIGNIFICANT SHORTWAVE SHIFTING THROUGH NRN WI. LATEST
RAP FORECASTS INDICATE THE LLJ WEAKENING TO AROUND 20 KTS AND
BACKING AROUND TO THE SOUTH BY MIDDAY...AND CONVECTIVE MODEL WHICH
HAS BEEN HANDLING THIS COMPLEX BEST /3-KM HRRR/ SHOWS LINE
WEAKENING AS IT SHIFTS SE INTO AFTERNOON. LATEST RADAR TRENDS SHOW
COLD POOL HAS SURGED OUT WELL AHEAD OF THE MIDDLE PORTION OF THE
LINE WITH A WEAKENING TREND ALREADY NOTED DOWN THE MISSISSIPPI
VALLEY...WHILE SVR/NEAR SVR WIND GUSTS CONTINUE IN PARTS OF NE IA
AN NORTH CENTRAL IL. ALSO BEST SHEAR REMAINS TO OUR NORTH TIED TO
THE SHORTWAVE AND WITH ALL THESE FACTORS IN MIND FEEL ACTIVITY
WILL WEAKEN AS IT APPROACHES THE NORTHERN CWA IN THE NEXT FEW
HOURS. HAVE UPPED POPS TO MID-HIGH CHANCE NORTH OF A GALESBURG TO EL
PASO LINE FOR EARLY AFTERNOON WITH CHANCES QUICKLY DIMINISHING
SOUTH OF THERE AS ACTIVITY TENDS TO FADE BY MID AFTERNOON. WILL
KEEP A CLOSE EYE ON THESE TRENDS THOUGH AS 1500-2000 J/KG MLCAPES
WILL BE PRESENT OVER CENTRAL IL. ANOTHER CONCERN WILL BE POTENTIAL
MID/LATE AFTERNOON DEVELOPMENT ALONG RESULTING OUTFLOW BOUNDARY
AND SOME HI-RES GUIDANCE INCLUDING HRRR AND 4KM NSSL WRF POINT TO
A FAVORED AREA ALONG AN INSTABILITY AXIS IN SE IA/NE MO/WEST
CENTRAL IL AFTER 21Z. THUS HAVE SLIGHT CHANCE POPS FOR THE FAR
WEST LATE AFTERNOON. OTHERWISE...BULK OF CWA SHOULD REMAIN DRY
TODAY AND HOT AND HUMID WEATHER WILL BE THE MAIN STORY. 10 AM
TEMPS ALREADY IN THE MID 80S AND WHILE INCOMING CIRRUS SHIELD MAY
INHIBIT TEMP RISE SOMEWHAT...STILL THINK WIDESPREAD HIGHS IN THE
LOW 90S LIKELY. THESE TEMPS COMBINED WITH DEWPOINTS IN THE UPPER
60S WILL PRODUCE AFTERNOON HEAT INDICES IN THE MID TO UPPER 90S.
&&
.AVIATION...
ISSUED 1240 PM CDT FRI JUN 21 2013
CONVECTION TO OUR NORTH CONTINUES TO SLOWLY SINK SOUTHEAST EARLY
THIS AFTERNOON. LEADING EDGE OF COLD POOL/OUTFLOW BOUNDARY CLEARLY EVIDENT
ON KDVN REFLECTIVITY AND IS SHIFTING SOUTH AROUND 20 KTS AND IS NOW
PUSHING INTO NORTHERN KNOX AND STARK COUNTIES. IF THIS MAINTAINS
TRENDS WOULD PASS THROUGH KPIA JUST BEFORE 19Z AND KBMI AT 20Z.
BEHIND THIS BOUNDARY WINDS SHIFT NORTH GUSTING AROUND 20 KTS. LIFT
OFF THE BOUNDARY IS PRODUCING SCATTERED TSRA BEHIND IT SO HAVE
INCLUDED VCTS AFTER PASSAGE FOR KPIA/KBMI WITH A TEMP PERIOD AT
KPIA WHERE HAVE HIGHER CONFIDENCE. BOUNDARY SHOULD EVENTUALLY SLOW AND
STALL AS MAIN CONVECTIVE BATCH TO THE NORTH SHIFTS EAST...AND
10-20 KT SOUTHWEST SYNOPTIC FLOW PROVIDES RESISTANCE. SO HAVE KEPT
THIS ACTIVITY OUT OF THE TERMINALS FARTHER SOUTH/EAST. GUSTY S/SW
WINDS WILL DROP BELOW 10 KTS AFTER SUNSET...THEN PICK UP AGAIN
AFTER 14Z/SAT.
25
&&
.PREV DISCUSSION...
ISSUED 256 AM CDT FRI JUN 21 2013
QUIET SUMMER-LIKE WEATHER WILL PREVAIL FOR SEVERAL DAYS...WITH
THE NEXT SIGNIFICANT CHANCE FOR RAIN HOLDING OFF UNTIL THE MIDDLE
OF NEXT WEEK.
SHORT TERM...TODAY THROUGH SUNDAY
MCS CURRENTLY ACROSS MINNESOTA WILL TRACK E/SE INTO WISCONSIN
THIS MORNING...REMAINING WELL NORTH OF CENTRAL ILLINOIS. FURTHER
SOUTH BENEATH THE BUILDING UPPER-LEVEL RIDGE...A WEAK FRONTAL
BOUNDARY IS SETTING OFF WIDELY SCATTERED SHOWERS/THUNDER ACROSS
EASTERN IOWA AND WESTERN ILLINOIS. THINK THIS SUBTLE BOUNDARY WILL
CONTINUE TO BE THE MAIN FOCUSING MECHANISM FOR ADDITIONAL
CONVECTION THROUGHOUT THE DAY. DUE TO LACK OF UPPER SUPPORT AND
WARMING MID-LEVELS BENEATH THE RIDGE...WIDESPREAD CONVECTION WILL
REMAIN UNLIKELY. WILL CARRY 20 POPS ALONG AND WEST OF I-55 IN
CLOSE PROXIMITY TO THE FRONT...WITH DRY WEATHER FURTHER EAST AND
SOUTH. WILL BE A VERY WARM/HUMID DAY AS WELL...WITH AFTERNOON
HIGHS REACHING THE LOWER 90S.
MODELS CONTINUE TO SUGGEST ISOLATED DIURNAL CONVECTION WILL
DEVELOP SATURDAY AFTERNOON...AS MID-LEVEL CAP REMAINS MARGINAL.
WILL CONTINUE TO FEATURE SLIGHT CHANCE POPS ACCORDINGLY. AS CAP
STRENGTHENS...SUNDAY LOOKS TO BE A SUNNY AND DRY DAY. MAIN STORY
TODAY THROUGH SUNDAY WILL BE THE HEAT. HIGH TEMPS EACH DAY WILL
RISE INTO THE LOWER 90S...WHILE OVERNIGHT LOWS ONLY DROP INTO THE
LOWER 70S. THESE TEMPERATURES COMBINED WITH DEWPOINTS IN THE UPPER
60S AND LOWER 70S...WILL PRODUCE AFTERNOON HEAT INDEX READINGS OF
95 TO 100 DEGREES.
LONG TERM...MONDAY THROUGH THURSDAY
UPPER RIDGE WILL GRADUALLY RETROGRADE WESTWARD NEXT WEEK...WITH
BOTH THE GFS AND ECMWF SHOWING RIDGE BUILDING OVER THE ROCKIES BY
WEDNESDAY/THURSDAY. AS A RESULT...INCREASING NORTHWESTERLY FLOW
DOWNSTREAM FROM THE RIDGE WILL PUSH A COLD FRONT INTO ILLINOIS BY
THE MIDDLE OF THE WEEK. MODELS STILL EXHIBIT A BIT OF A SPREAD IN
SOLUTIONS...BUT GENERAL CONSENSUS BRINGS FRONT INTO THE AREA BY
WEDNESDAY NIGHT/THURSDAY. HAVE INTRODUCED CHANCE POPS ACROSS THE
NORTHERN CWA ON WEDNESDAY...THEN EVERYWHERE WEDNESDAY NIGHT INTO
THURSDAY. ONCE FRONT PASSES...COOLER AND LESS HUMID WEATHER WILL
ARRIVE BY THE END OF NEXT WEEK.
BARNES
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1152 AM CDT FRI JUN 21 2013
.MESOSCALE DISCUSSION...
1150 AM CDT UPDATE
CONVECTION HAS ORGANIZED INTO A LINE FROM NE OF MILWAUKEE BACK TO
NEAR PRINCETON AND CONTINUES TO MOVE EASTWARD. LATEST MESOANALYSIS
SHOWS THE CIN HAS ERODED AHEAD OF THE LINE ACROSS THE AREA WITH
SURFACE BASED AND MIXED LAYER INSTABILITY INCREASING TO AROUND
1500 J/KG. OUTFLOW HAS PUSHED AHEAD OF THE NORTHERN PART OF THE
LINE BUT CONTINUES TO INTERACT WITH THE SOUTHWEST PORTION ACROSS
SOUTHERN DEKALB...LEE AND FAR NW LA SALLE COUNTIES. THE AXIS OF
GREATEST INSTABILITY ALONG WITH STEEPEST LAPSE RATES IS ACROSS THE
SOUTHWEST CWA WHICH SUPPORTS LATEST RADAR TRENDS OF RENEWED AND
FAIRLY STRONG DEVELOPMENT OF STORMS BACK TOWARDS PRINCETON.
OVERALL THE GREATEST SEVERE THREAT APPEARS TO BE FROM ALONG AND
SOUTH OF INTERSTATE 88 BACK TO INTERSTATE 80 WHERE BEST PARAMETERS
LINE UP. SOUTHERN EXTENT MAY EXPAND FURTHER SOUTHWEST AND
EVENTUALLY AFFECT PONTIAC AND POINTS SOUTH EARLY THIS AFTERNOON AS
THE OUTFLOW SLIPS SOUTHWARD. TO THE NORTH...SEVERE THREAT LOOKS
MORE LIMITED WITH THAT PORTION OF THE LINE LOOKING OUTFLOW
DOMINANT AT THE MOMENT. LOCALIZED FLOODING IS A POSSIBILITY WITH A
VERY MOIST ATMOSPHERE AND SOME REGENERATION OF CELLS OVER AREAS
PREVIOUSLY AFFECTED BY HEAVY DOWNPOURS. THIS WILL BE FOCUSED
CLOSER TO THE OUTFLOW BOUNDARY ACROSS SOUTHERN LEE AND MAY EXPAND
INTO LA SALLE COUNTY IN THE NEXT HOUR OR SO. OTHERWISE URBAN AREAS
WILL BE SUSCEPTIBLE TO PONDING AND LOCALIZED FLOODING. OVERALL
HAVE SEEN RAINFALL RATES ON THE ORDER OF AROUND AN INCH PER HOUR.
MDB
&&
.DISCUSSION...
329 AM CDT
THE MAIN FORECAST CHALLENGE FOR THE SHORT TERM WILL BE THE EVOLUTION
OF THE MCS OVER THE UPPER MS VALLEY TODAY. THIS COULD BE FOLLOWED
BY ADDITIONAL STORM CLUSTERS THROUGH SATURDAY...AND AGAIN MONDAY
THROUGH WEDNESDAY. ALSO THE BUILDING HEAT AND HUMIDITY THROUGH
THE MIDDLE OF NEXT WEEK.
IN THE SHORT TERM A NARROW BAND OF SHOWERS AND WEAK THUNDERSTORMS
EXTENDS FROM WESTERN WI TO THE IL/IA BORDER. THIS ACTIVITY OCCURRING
ALONG AN AXIS OF HIGHER LOW LEVEL MOISTURE AND THE EASTERN EDGE OF
THE LOW LEVEL JET. EXPECT THIS ACTIVITY TO WEAKEN AND DIE EARLY THIS
MORNING AS IT MOVES INTO DRIER AND MORE STABLE ATMOSPHERE. HAVE SOME
LOW POPS FOR FAR WESTERN COUNTIES THROUGH MID MORNING. MEANWHILE
VERY ACTIVE MCS OVER MN DIVING SOUTHEAST. THIS ACTIVITY SHOULD BE
ON A DIURNALLY WEAKENING TREND LATER THIS MORNING. MEAN MID AND
UPPER LEVEL WINDS ARE WESTERLY WITH FLAT RIDGE ACROSS THE UPPER MS
VALLEY AND GREAT LAKES...WHICH MIGHT SUGGEST THIS WILL REMAIN
MAINLY NORTH OVER WISCONSIN...BUT ACTIVITY IS DROPPING SOUTHEAST
AS CONVECTION BACK BUILDS INTO LOW LEVEL JET. IF IT HOLDS
TOGETHER ON ITS PRESENT COURSE...IT WILL BE APPROACHING NORTHWEST
AND NORTH CENTRAL IL BY LATE MORNING. HRRR SEEMS TO BE THE MOST
AGGRESSIVE OF THE SHORT TERM GUIDANCE IN BRINGING PRECIP INTO
NORTHERN IL TODAY. DEEP LAYER SHEAR WILL BE LACKING THIS FAR
SOUTH BUT WITH BUILDING HEAT AND SURFACE DEW POINTS CLIMBING INTO
THE MID AND UPPER 60S...THERE MAY BE SUFFICIENT LOW LEVEL
INSTABILITY FOR STORMS TO CONTINUE SOUTHEASTWARD INTO IL. HAVE
MAINTAINED 30-40 PERCENT POPS MAINLY FOR NORTHERN COUPLE OF TIERS
OF COUNTIES. SPC HAS MUCH OF NORTHERN IL IN SLIGHT RISK FOR WIND
AND HAIL THREAT. THE ASSOCIATED CIRRUS SHIELD MAY ALSO IMPACT
TEMPERATURES. THEREFORE HAVE LOWERED MAX TEMPS ACROSS THE FAR NORTH
DOWN A COUPLE DEGREES TO THE MID 80S WHILE KEEPING MAX TEMPS IN
UPPER 80S TO NEAR 90 FURTHER SOUTH. EXPECT SOUTH WINDS TO BE
SUFFICIENTLY STRONG TO PREVENT A LAKE BREEZE. ALTHOUGH WITH SOUTH
TO SLIGHTLY EAST OF SOUTH WINDS...A WEAK LAKE BREEZE MAY DRIFT
ONSHORE ACROSS NORTHERN COOK AND LAKE COUNTY IN THIS AFTERNOON.
ANOTHER MCS MAY DEVELOP AND MOVE THROUGH THE NORTHERN PART OF THE
FORECAST AREA AGAIN SATURDAY AS A SERIES OF WEAK WAVES MOVES THROUGH
THE RING OF FIRE ACROSS THE GREAT LAKES. BUT LOW CONFIDENCE THIS FAR
OUT. THE GENERAL TREND OF THE MODELS IS TO SLOWLY BUILD THE RIDGE
INTO THE WESTERN GREAT LAKES OVER THE WEEKEND. THEREFORE HAVE JUST
LOW CHANCE POPS FOR SATURDAY AND A DRY FORECAST FOR SUNDAY. MONDAY
THROUGH WEDNESDAY A SERIES OF WAVES SUPPRESSES THE RIDGE...WHICH
EVENTUALLY RE-ESTABLISHES ITSELF OVER THE WESTERN US. BY THE END
OF THE WEEK MODELS IN DECENT AGREEMENT IN DEVELOPING AN UPPER LOW
OVER THE GREAT LAKES.
MAX TEMPERATURES EXPECTED TO BE IN THE UPPER 80S TO AROUND 90 TODAY
THROUGH WEDNESDAY...WITH DEW POINTS IN THE UPPER 60S TO AROUND 70.
THIS PRODUCES HEAT INDEX VALUES IN MID TO UPPER 90S. THIS IS
BELOW LOCAL HEAT ADVISORY THRESHOLDS. HOWEVER SEEING AS THIS IS
THE FIRST HEAT WAVE OF THE SUMMER AND IT MAY PERSIST FOR SEVERAL
DAYS. A HEAT ADVISORY MAY NEED TO BE CONSIDERED BY EARLY TO MID
WEEK. ANY THUNDERSTORMS AND ASSOCIATED CLOUD COVER/OUTFLOW
BOUNDARIES MAY TEMPORARILY COOL THINGS DOWN AND IMPACT ANY FUTURE
DECISIONS ON HEAT HEADLINES.
PATTERN LOOKS TO BECOME MUCH COOLER NEXT WEEKEND.
ALLSOPP
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* LINE OF TS ARRIVING IN THE 17-18Z TIME FRAME.
* WIND SHIFT TO NW WITH GUSTS EXPECTED AND VSBY BRIEFLY DOWN TO
AROUND 1SM.
* LIGHT/VARIABLE NW-NE WINDS EXPECTED BEHIND MAIN LINE OF
STORMS...WINDS THEN EXPECTED TO RETURN TO SOUTHERLY BY MID
AFTERNOON.
* -RA/EMBEDDED TS LINGERS THROUGH EARLY AFTERNOON.
MDB
//DISCUSSION...UPDATED 16Z...
LINE OF STORMS NOW ORIENTED FROM W OF KENW TO KDKB TO W OF KVYS AND
MOVING EAST. SOUTHERN EXTENT HAS INCREASED SO HAVE SO HAVE HIGHER
CONFIDENCE IN MDW BEING AFFECTED AND HAVE AMENDED TO SHOW THIS.
OTHERWISE ORD/DPA WILL BE AFFECTED AS WELL. WILL LIKELY NEED TO
HIT THE TS HARDER AT GYY WITH ARRIVAL TOWARD 1830/19Z OR SO.
EXPECT WIND SHIFT TO THE N/NNW WITH THE STORMS WITH WINDS THEN
DIMINISHING AND BECOMING VARIABLE FROM THE NORTH AND EAST...BEFORE
EVENTUALLY BECOMING SOUTHERLY AGAIN.
MDB
FROM 12Z...
LARGE COMPLEX OF THUNDERSTORMS OVER THE UPPER MIDWEST EARLY THIS
MORNING WAS SLOWLY SLIDING SOUTHEAST. REGIONAL RADAR INDICATED A
LINE OF THUNDERSTORMS STILL ASSOCIATED WITH THIS COMPLEX
STRETCHING FROM FAR NORTHEAST IOWA INTO WEST CENTRAL WISCONSIN.
GUIDANCE INDICATES THAT THIS LINE WILL BEGIN TO WEAKEN AS IT
CONTINUES TO SLIDES SOUTHEAST. CURRENT THINKING IS THAT SOME
REMNANTS OF THIS LINE OF THUNDERSTORMS MAY ARRIVE LATER THIS
MORNING. THE TIMING WOULD BE INTO RFD ARND 16Z THEN FURTHER EAST
AT ORD/MDW/DPA/GYY CLOSER TO 18Z ARRIVAL. WITH SOME HEATING AHEAD
OF THIS LINE OVER NORTHERN IL/NORTHWEST IN AIRFIELDS...THIS MAY
AID IN MAINTAINING THIS LINE OF CONVECTION. AT THIS TIME HAVE
OPTED TO GO WITH A VCTS RATHER THAN A PREVAILING MENTION. BUT THAT
MAY NEED TO BE CHANGED FOR THE 14Z AMD.
SOUTHERLY WINDS WILL CONTINUE THRU MUCH OF THE DAY WITH OCCASIONAL
GUSTS BEGINNING TO OCCUR LATER THIS MORNING TO AROUND 20 KT.
CLOUD DECKS SHUD BE AROUND 5KFT AGL...AND MAY SLOWLY GROW IN
COVERAGE THROUGHOUT THE AFT FROM A SCT TO BKN. GUIDANCE IS THEN
REDEVELOPING A LINE OF SHOWERS/THUNDERSTORMS LATE THIS AFTN/EVE
ALONG A REMNANT BOUNDARY FROM THIS MORNING CONVECTION. SOME OF
THESE THUNDERSTORMS COULD BE STRONG TO SEVERE...WITH THE MAIN HAZARDS
BEING WIND/HAIL.
SOUTHERLY WINDS PERSIST OVERNIGHT AND DIMINISH TO ARND 10KT...WITH
SOME TURNING TO THE SOUTHWEST EXPECTED OVERNIGHT TOWARDS DAYBREAK
SAT. OVERALL EXPECT VFR CONDS THROUGHOUT...HOWEVER WITH ANY
THUNDERSTORM ACTIVITY THIS COULD EASILY BE LIMITED TO MVFR.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH CONFIDENCE IN TS TIMING.
* HIGH CONFIDENCE IN WIND SHIFT TO NW WITH GUSTS...MEDIUM
CONFIDENCE IN GUSTS SPEEDS...HIGH CONFIDENCE IN IFR VSBY.
* MEDIUM CONFIDENCE IN WIND TRENDS BEHIND MAIN LINE OF
STORMS...LOW CONFIDENCE IN TIMING OF DIRECTION CHANGES.
* LOW-MEDIUM CONFIDENCE IN COVERAGE/DURATION OF LINGERING
-RA/EMBEDDED TS EARLY THIS AFTERNOON.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...VFR.
SUNDAY...MAINLY VFR. CHC THUNDERSTORMS LATE.
MONDAY THROUGH THURSDAY...PERIODIC CHANCES FOR THUNDERSTORMS.
OTHERWISE VFR.
BEACHLER
&&
.MARINE...
240 AM CDT
MAIN CONCERN FOR LAKE MICHIGAN WILL BE POTENTIAL FOR FOG
DEVELOPMENT AND TIMING...ALONG WITH CHANCES FOR THUNDERSTORMS. AT
THIS TIME THERE DOES NOT APPEAR TO BE ANY WIND/WAVE HAZARDS
EXPECTED IN THE NEXT SEVERAL DAYS.
HIGH PRESURE ANCHORED ACROSS THE WESTERN ATLANTIC OCEAN ALONG WITH
A BROAD LOW PRESSURE ANCHORED OVER THE CENTRAL PLAINS...WILL
MAINTAIN THE SOUTHERLY FLOW OVER THE LAKE. IN ADDITION VERY WARM
AIR WILL SLIDE OVER THE COOLER OPEN WATERS OF THE LAKE...AND HELP
TO KEEP WAVES FROM BUILDING TO LARGE. THE GRADIENT THIS AFTERNOON
DOES INCREASE WHICH MAY ALLOW WINDS TO INCREASE TO AROUND 20-25KT
FOR THE NORTHERN HALF OF THE LAKE...HOWEVER WAVES SHOULD ONLY
BUILD TO 2 TO 4 FT. AT TIMES WINDS MAY GUST TO 25 KT FURTHER SOUTH
THIS AFTERNOON. THUNDERSTORMS ARE FORECAST FOR THE NEXT SEVERAL
DAYS...HOWEVER THESE DO NOT APPEAR TO BE AN ALL DAY OR NIGHT
THING. BUT WINDS/WAVES WILL BE HIGHER IN AND AROUND ANY
THUNDERSTORMS THAT DO SLIDE ACROSS THE LAKE.
AS MENTIONED EARLIER ABOUT THE FOG DEVELOPMENT. IT DOES APPEAR
THAT WITH ENOUGH WIND THIS AFTERNOON FOG WILL HOLD OFF UNTIL
PERHAPS LATE TONIGHT OR POSSIBLY SATURDAY. A WARM FRONT WILL LIFT
NORTH OVER THE LAKE...WITH FOG DEVELOPMENT EXPECTED JUST AFTER
PASSAGE. THIS STILL APPEARS TO FAVOR THE NORTHERN PORTIONS OF THE
LAKE AND AT TIMES COULD BE DENSE. ONCE FOG DEVELOPS IT COULD
EASILY LINGER THROUGH EARLY NEXT WEEK AS THE WINDS ARE NOT
EXPECTED TO BE VERY STRONG.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1133 AM CDT FRI JUN 21 2013
.MESOSCALE DISCUSSION...
1000 AM CDT
COMPLEX OF STORMS CONTINUES TO EVOLVE ACROSS SOUTHERN WI/FAR NW
IL/NE IA. LATEST RADAR TRENDS SHOW REFLECTIVITY WEAKENING TOWARD
THE DBQ AREA WITH A MORE PERSISTENT LINE NOW SET UP FROM SOUTHERN
CENTRAL WI BACK TO FREEPORT AND SAVANNA MOVING EASTWARD. THE
ATMOSPHERE AHEAD OF THIS ACROSS THE LOCAL AREA IS STILL CAPPED AND
THE COMPLEX IS BEGINNING TO OUTRUN BETTER DEEP LAYER SHEAR. SOME
OUTFLOW IS PRESENT BASED ON SFC OBS SHIFTING WINDS TO THE
NORTHWEST WITH SOME GUSTINESS BUT THE LINE MAY BE BECOMING
ELEVATED. THAT SAID...WINDS SOUTH OF THE LINE HAVE TURNED MORE
SOUTH-SOUTHWEST HELPING TO FEED SLIGHTLY HIGHER DEWPOINT AIR
NORTHWARD. HOWEVER...IT DOES LOOK TO BE A FEW MORE HOURS BEFORE
CAPPING CAN ERODE WHICH WOULD LIKELY BE TOO LATE TO INTERSECT WITH
CURRENT STORMS. AT THIS POINT EXPECT THE BEST COVERAGE OF STORMS
TO MOVE EAST OR EAST-SOUTHEAST ALONG A LINE FROM FREEPORT TO
CHICAGO THOUGH THE SOUTHERN END OF THE LINE MAY BE MORE VARIABLE
IN COVERAGE. HEAVY DOWNPOURS WILL OCCUR AND THE LATEST RADAR SCANS
HAVE SHOWN A SLOWING TREND SO LOCALIZED FLOODING IS A THREAT WITH
1 INCH+ PER HOUR RAINFALL RATES LIKELY BASED ON UPSTREAM REPORTS.
AN ISOLATED STRONG/SEVERE WIND THREAT EXISTS MAINLY IF CAPPING CAN
ERODE. A BOUNDARY MAY LAY OUT ACROSS THE AREA THANKS TO THIS
ACTIVITY LEADING TO AT LEAST A LOW CHANCE FOR NEW DEVELOPMENT
LATER TODAY.
MDB
&&
.DISCUSSION...
329 AM CDT
THE MAIN FORECAST CHALLENGE FOR THE SHORT TERM WILL BE THE EVOLUTION
OF THE MCS OVER THE UPPER MS VALLEY TODAY. THIS COULD BE FOLLOWED
BY ADDITIONAL STORM CLUSTERS THROUGH SATURDAY...AND AGAIN MONDAY
THROUGH WEDNESDAY. ALSO THE BUILDING HEAT AND HUMIDITY THROUGH
THE MIDDLE OF NEXT WEEK.
IN THE SHORT TERM A NARROW BAND OF SHOWERS AND WEAK THUNDERSTORMS
EXTENDS FROM WESTERN WI TO THE IL/IA BORDER. THIS ACTIVITY OCCURRING
ALONG AN AXIS OF HIGHER LOW LEVEL MOISTURE AND THE EASTERN EDGE OF
THE LOW LEVEL JET. EXPECT THIS ACTIVITY TO WEAKEN AND DIE EARLY THIS
MORNING AS IT MOVES INTO DRIER AND MORE STABLE ATMOSPHERE. HAVE SOME
LOW POPS FOR FAR WESTERN COUNTIES THROUGH MID MORNING. MEANWHILE
VERY ACTIVE MCS OVER MN DIVING SOUTHEAST. THIS ACTIVITY SHOULD BE
ON A DIURNALLY WEAKENING TREND LATER THIS MORNING. MEAN MID AND
UPPER LEVEL WINDS ARE WESTERLY WITH FLAT RIDGE ACROSS THE UPPER MS
VALLEY AND GREAT LAKES...WHICH MIGHT SUGGEST THIS WILL REMAIN
MAINLY NORTH OVER WISCONSIN...BUT ACTIVITY IS DROPPING SOUTHEAST
AS CONVECTION BACK BUILDS INTO LOW LEVEL JET. IF IT HOLDS
TOGETHER ON ITS PRESENT COURSE...IT WILL BE APPROACHING NORTHWEST
AND NORTH CENTRAL IL BY LATE MORNING. HRRR SEEMS TO BE THE MOST
AGGRESSIVE OF THE SHORT TERM GUIDANCE IN BRINGING PRECIP INTO
NORTHERN IL TODAY. DEEP LAYER SHEAR WILL BE LACKING THIS FAR
SOUTH BUT WITH BUILDING HEAT AND SURFACE DEW POINTS CLIMBING INTO
THE MID AND UPPER 60S...THERE MAY BE SUFFICIENT LOW LEVEL
INSTABILITY FOR STORMS TO CONTINUE SOUTHEASTWARD INTO IL. HAVE
MAINTAINED 30-40 PERCENT POPS MAINLY FOR NORTHERN COUPLE OF TIERS
OF COUNTIES. SPC HAS MUCH OF NORTHERN IL IN SLIGHT RISK FOR WIND
AND HAIL THREAT. THE ASSOCIATED CIRRUS SHIELD MAY ALSO IMPACT
TEMPERATURES. THEREFORE HAVE LOWERED MAX TEMPS ACROSS THE FAR NORTH
DOWN A COUPLE DEGREES TO THE MID 80S WHILE KEEPING MAX TEMPS IN
UPPER 80S TO NEAR 90 FURTHER SOUTH. EXPECT SOUTH WINDS TO BE
SUFFICIENTLY STRONG TO PREVENT A LAKE BREEZE. ALTHOUGH WITH SOUTH
TO SLIGHTLY EAST OF SOUTH WINDS...A WEAK LAKE BREEZE MAY DRIFT
ONSHORE ACROSS NORTHERN COOK AND LAKE COUNTY IN THIS AFTERNOON.
ANOTHER MCS MAY DEVELOP AND MOVE THROUGH THE NORTHERN PART OF THE
FORECAST AREA AGAIN SATURDAY AS A SERIES OF WEAK WAVES MOVES THROUGH
THE RING OF FIRE ACROSS THE GREAT LAKES. BUT LOW CONFIDENCE THIS FAR
OUT. THE GENERAL TREND OF THE MODELS IS TO SLOWLY BUILD THE RIDGE
INTO THE WESTERN GREAT LAKES OVER THE WEEKEND. THEREFORE HAVE JUST
LOW CHANCE POPS FOR SATURDAY AND A DRY FORECAST FOR SUNDAY. MONDAY
THROUGH WEDNESDAY A SERIES OF WAVES SUPPRESSES THE RIDGE...WHICH
EVENTUALLY RE-ESTABLISHES ITSELF OVER THE WESTERN US. BY THE END
OF THE WEEK MODELS IN DECENT AGREEMENT IN DEVELOPING AN UPPER LOW
OVER THE GREAT LAKES.
MAX TEMPERATURES EXPECTED TO BE IN THE UPPER 80S TO AROUND 90 TODAY
THROUGH WEDNESDAY...WITH DEW POINTS IN THE UPPER 60S TO AROUND 70.
THIS PRODUCES HEAT INDEX VALUES IN MID TO UPPER 90S. THIS IS
BELOW LOCAL HEAT ADVISORY THRESHOLDS. HOWEVER SEEING AS THIS IS
THE FIRST HEAT WAVE OF THE SUMMER AND IT MAY PERSIST FOR SEVERAL
DAYS. A HEAT ADVISORY MAY NEED TO BE CONSIDERED BY EARLY TO MID
WEEK. ANY THUNDERSTORMS AND ASSOCIATED CLOUD COVER/OUTFLOW
BOUNDARIES MAY TEMPORARILY COOL THINGS DOWN AND IMPACT ANY FUTURE
DECISIONS ON HEAT HEADLINES.
PATTERN LOOKS TO BECOME MUCH COOLER NEXT WEEKEND.
ALLSOPP
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* LINE OF TS ARRIVING IN THE 17-18Z TIME FRAME.
* WIND SHIFT TO NW WITH GUSTS EXPECTED AND VSBY BRIEFLY DOWN TO
AROUND 1SM.
* LIGHT/VARIABLE NW-NE WINDS EXPECTED BEHIND MAIN LINE OF
STORMS...WINDS THEN EXPECTED TO RETURN TO SOUTHERLY BY MID
AFTERNOON.
* -RA/EMBEDDED TS LINGERS THROUGH EARLY AFTERNOON.
MDB
//DISCUSSION...UPDATED 16Z...
LINE OF STORMS NOW ORIENTED FROM W OF KENW TO KDKB TO W OF KVYS AND
MOVING EAST. SOUTHERN EXTENT HAS INCREASED SO HAVE SO HAVE HIGHER
CONFIDENCE IN MDW BEING AFFECTED AND HAVE AMENDED TO SHOW THIS.
OTHERWISE ORD/DPA WILL BE AFFECTED AS WELL. WILL LIKELY NEED TO
HIT THE TS HARDER AT GYY WITH ARRIVAL TOWARD 1830/19Z OR SO.
EXPECT WIND SHIFT TO THE N/NNW WITH THE STORMS WITH WINDS THEN
DIMINISHING AND BECOMING VARIABLE FROM THE NORTH AND EAST...BEFORE
EVENTUALLY BECOMING SOUTHERLY AGAIN.
MDB
FROM 12Z...
LARGE COMPLEX OF THUNDERSTORMS OVER THE UPPER MIDWEST EARLY THIS
MORNING WAS SLOWLY SLIDING SOUTHEAST. REGIONAL RADAR INDICATED A
LINE OF THUNDERSTORMS STILL ASSOCIATED WITH THIS COMPLEX
STRETCHING FROM FAR NORTHEAST IOWA INTO WEST CENTRAL WISCONSIN.
GUIDANCE INDICATES THAT THIS LINE WILL BEGIN TO WEAKEN AS IT
CONTINUES TO SLIDES SOUTHEAST. CURRENT THINKING IS THAT SOME
REMNANTS OF THIS LINE OF THUNDERSTORMS MAY ARRIVE LATER THIS
MORNING. THE TIMING WOULD BE INTO RFD ARND 16Z THEN FURTHER EAST
AT ORD/MDW/DPA/GYY CLOSER TO 18Z ARRIVAL. WITH SOME HEATING AHEAD
OF THIS LINE OVER NORTHERN IL/NORTHWEST IN AIRFIELDS...THIS MAY
AID IN MAINTAINING THIS LINE OF CONVECTION. AT THIS TIME HAVE
OPTED TO GO WITH A VCTS RATHER THAN A PREVAILING MENTION. BUT THAT
MAY NEED TO BE CHANGED FOR THE 14Z AMD.
SOUTHERLY WINDS WILL CONTINUE THRU MUCH OF THE DAY WITH OCCASIONAL
GUSTS BEGINNING TO OCCUR LATER THIS MORNING TO AROUND 20 KT.
CLOUD DECKS SHUD BE AROUND 5KFT AGL...AND MAY SLOWLY GROW IN
COVERAGE THROUGHOUT THE AFT FROM A SCT TO BKN. GUIDANCE IS THEN
REDEVELOPING A LINE OF SHOWERS/THUNDERSTORMS LATE THIS AFTN/EVE
ALONG A REMNANT BOUNDARY FROM THIS MORNING CONVECTION. SOME OF
THESE THUNDERSTORMS COULD BE STRONG TO SEVERE...WITH THE MAIN HAZARDS
BEING WIND/HAIL.
SOUTHERLY WINDS PERSIST OVERNIGHT AND DIMINISH TO ARND 10KT...WITH
SOME TURNING TO THE SOUTHWEST EXPECTED OVERNIGHT TOWARDS DAYBREAK
SAT. OVERALL EXPECT VFR CONDS THROUGHOUT...HOWEVER WITH ANY
THUNDERSTORM ACTIVITY THIS COULD EASILY BE LIMITED TO MVFR.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH CONFIDENCE IN TS TIMING.
* HIGH CONFIDENCE IN WIND SHIFT TO NW WITH GUSTS...MEDIUM
CONFIDENCE IN GUSTS SPEEDS...HIGH CONFIDENCE IN IFR VSBY.
* MEDIUM CONFIDENCE IN WIND TRENDS BEHIND MAIN LINE OF
STORMS...LOW CONFIDENCE IN TIMING OF DIRECTION CHANGES.
* LOW-MEDIUM CONFIDENCE IN COVERAGE/DURATION OF LINGERING
-RA/EMBEDDED TS EARLY THIS AFTERNOON.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...VFR.
SUNDAY...MAINLY VFR. CHC THUNDERSTORMS LATE.
MONDAY THROUGH THURSDAY...PERIODIC CHANCES FOR THUNDERSTORMS.
OTHERWISE VFR.
BEACHLER
&&
.MARINE...
240 AM CDT
MAIN CONCERN FOR LAKE MICHIGAN WILL BE POTENTIAL FOR FOG
DEVELOPMENT AND TIMING...ALONG WITH CHANCES FOR THUNDERSTORMS. AT
THIS TIME THERE DOES NOT APPEAR TO BE ANY WIND/WAVE HAZARDS
EXPECTED IN THE NEXT SEVERAL DAYS.
HIGH PRESURE ANCHORED ACROSS THE WESTERN ATLANTIC OCEAN ALONG WITH
A BROAD LOW PRESSURE ANCHORED OVER THE CENTRAL PLAINS...WILL
MAINTAIN THE SOUTHERLY FLOW OVER THE LAKE. IN ADDITION VERY WARM
AIR WILL SLIDE OVER THE COOLER OPEN WATERS OF THE LAKE...AND HELP
TO KEEP WAVES FROM BUILDING TO LARGE. THE GRADIENT THIS AFTERNOON
DOES INCREASE WHICH MAY ALLOW WINDS TO INCREASE TO AROUND 20-25KT
FOR THE NORTHERN HALF OF THE LAKE...HOWEVER WAVES SHOULD ONLY
BUILD TO 2 TO 4 FT. AT TIMES WINDS MAY GUST TO 25 KT FURTHER SOUTH
THIS AFTERNOON. THUNDERSTORMS ARE FORECAST FOR THE NEXT SEVERAL
DAYS...HOWEVER THESE DO NOT APPEAR TO BE AN ALL DAY OR NIGHT
THING. BUT WINDS/WAVES WILL BE HIGHER IN AND AROUND ANY
THUNDERSTORMS THAT DO SLIDE ACROSS THE LAKE.
AS MENTIONED EARLIER ABOUT THE FOG DEVELOPMENT. IT DOES APPEAR
THAT WITH ENOUGH WIND THIS AFTERNOON FOG WILL HOLD OFF UNTIL
PERHAPS LATE TONIGHT OR POSSIBLY SATURDAY. A WARM FRONT WILL LIFT
NORTH OVER THE LAKE...WITH FOG DEVELOPMENT EXPECTED JUST AFTER
PASSAGE. THIS STILL APPEARS TO FAVOR THE NORTHERN PORTIONS OF THE
LAKE AND AT TIMES COULD BE DENSE. ONCE FOG DEVELOPS IT COULD
EASILY LINGER THROUGH EARLY NEXT WEEK AS THE WINDS ARE NOT
EXPECTED TO BE VERY STRONG.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1039 AM CDT FRI JUN 21 2013
.DISCUSSION...
ISSUED 1039 AM CDT FRI JUN 21 2013
SEVERE CONVECTIVE COMPLEX TO OUR NORTH MAIN ISSUE. THIS HAS BEEN
MAINTAINED BY A 40-45 KT SW 925 MB LOW LEVEL JET EVIDENT ON AREA
VWP/S AND A SIGNIFICANT SHORTWAVE SHIFTING THROUGH NRN WI. LATEST
RAP FORECASTS INDICATE THE LLJ WEAKENING TO AROUND 20 KTS AND
BACKING AROUND TO THE SOUTH BY MIDDAY...AND CONVECTIVE MODEL WHICH
HAS BEEN HANDLING THIS COMPLEX BEST /3-KM HRRR/ SHOWS LINE
WEAKENING AS IT SHIFTS SE INTO AFTERNOON. LATEST RADAR TRENDS SHOW
COLD POOL HAS SURGED OUT WELL AHEAD OF THE MIDDLE PORTION OF THE
LINE WITH A WEAKENING TREND ALREADY NOTED DOWN THE MISSISSIPPI
VALLEY...WHILE SVR/NEAR SVR WIND GUSTS CONTINUE IN PARTS OF NE IA
AN NORTH CENTRAL IL. ALSO BEST SHEAR REMAINS TO OUR NORTH TIED TO
THE SHORTWAVE AND WITH ALL THESE FACTORS IN MIND FEEL ACTIVITY
WILL WEAKEN AS IT APPROACHES THE NORTHERN CWA IN THE NEXT FEW
HOURS. HAVE UPPED POPS TO MID-HIGH CHANCE NORTH OF A GALESBURG TO EL
PASO LINE FOR EARLY AFTERNOON WITH CHANCES QUICKLY DIMINISHING
SOUTH OF THERE AS ACTIVITY TENDS TO FADE BY MID AFTERNOON. WILL
KEEP A CLOSE EYE ON THESE TRENDS THOUGH AS 1500-2000 J/KG MLCAPES
WILL BE PRESENT OVER CENTRAL IL. ANOTHER CONCERN WILL BE POTENTIAL
MID/LATE AFTERNOON DEVELOPMENT ALONG RESULTING OUTFLOW BOUNDARY
AND SOME HI-RES GUIDANCE INCLUDING HRRR AND 4KM NSSL WRF POINT TO
A FAVORED AREA ALONG AN INSTABILITY AXIS IN SE IA/NE MO/WEST
CENTRAL IL AFTER 21Z. THUS HAVE SLIGHT CHANCE POPS FOR THE FAR
WEST LATE AFTERNOON. OTHERWISE...BULK OF CWA SHOULD REMAIN DRY
TODAY AND HOT AND HUMID WEATHER WILL BE THE MAIN STORY. 10 AM
TEMPS ALREADY IN THE MID 80S AND WHILE INCOMING CIRRUS SHIELD MAY
INHIBIT TEMP RISE SOMEWHAT...STILL THINK WIDESPREAD HIGHS IN THE
LOW 90S LIKELY. THESE TEMPS COMBINED WITH DEWPOINTS IN THE UPPER
60S WILL PRODUCE AFTERNOON HEAT INDICES IN THE MID TO UPPER 90S.
25
&&
.AVIATION...
ISSUED 655 AM CDT FRI JUN 21 2013
1027 MB HIGH PRESSURE OFF THE MID ATLANTIC COAST AND RIDGING
WESTWARD INTO THE OHIO VALLEY TO BE NEARLY STATIONARY INTO SAT
MORNING WHILE 1003 MB LOW PRESSUE OVER EASTERN CO INTO SW NEBRASKA
WITH FRONTAL BOUNDARY EXTENDING NE INTO SOUTHERN MN TO ALSO REMAIN
IN PLACE NEXT 24 HOURS. VFR CONDITIONS SHOULD CONTINUE ACROSS THE
CENTRAL IL TERMINAL AIRPORTS NEXT 24 HOURS THROUGH 12Z/7 AM SAT.
SCATTERED TO BROKEN MID/HIGH CLOUDS TO SPREAD SE FROM THE IL RIVER
ACROSS CENTRAL IL DURING TODAY AS SCATTERED CUMULUS CLOUDS WITH
BASES OF 4-6K FT DEVELOP AFTER 15Z/10 AM. CURULE FROM RUC MODEL
SHOWS BROKEN CUMULUS CEILINGS NORTH AND SOUTH OF CENTRAL IL THIS
AFTERNOON. HAVE VCSH AT PIA OVER IL RIVER VALLEY THIS AFTERNOON
AFTER 18Z/1 PM BUT BETTER CHANCE OF CONVECTION WILL BE NW TOWARD
IA. FEW TO SCATTERED CLOUDS LINGER TONIGHT. SOUTH WINDS 10-15 KTS
WITH GUSTS AROUND 20 KTS AFTER 15Z/10 AM TODAY AND DIMINISH TO
5-10 KTS AFTER SUNSET.
07
&&
.PREV DISCUSSION...
ISSUED 256 AM CDT FRI JUN 21 2013
QUIET SUMMER-LIKE WEATHER WILL PREVAIL FOR SEVERAL DAYS...WITH
THE NEXT SIGNIFICANT CHANCE FOR RAIN HOLDING OFF UNTIL THE MIDDLE
OF NEXT WEEK.
SHORT TERM...TODAY THROUGH SUNDAY
MCS CURRENTLY ACROSS MINNESOTA WILL TRACK E/SE INTO WISCONSIN
THIS MORNING...REMAINING WELL NORTH OF CENTRAL ILLINOIS. FURTHER
SOUTH BENEATH THE BUILDING UPPER-LEVEL RIDGE...A WEAK FRONTAL
BOUNDARY IS SETTING OFF WIDELY SCATTERED SHOWERS/THUNDER ACROSS
EASTERN IOWA AND WESTERN ILLINOIS. THINK THIS SUBTLE BOUNDARY WILL
CONTINUE TO BE THE MAIN FOCUSING MECHANISM FOR ADDITIONAL
CONVECTION THROUGHOUT THE DAY. DUE TO LACK OF UPPER SUPPORT AND
WARMING MID-LEVELS BENEATH THE RIDGE...WIDESPREAD CONVECTION WILL
REMAIN UNLIKELY. WILL CARRY 20 POPS ALONG AND WEST OF I-55 IN
CLOSE PROXIMITY TO THE FRONT...WITH DRY WEATHER FURTHER EAST AND
SOUTH. WILL BE A VERY WARM/HUMID DAY AS WELL...WITH AFTERNOON
HIGHS REACHING THE LOWER 90S.
MODELS CONTINUE TO SUGGEST ISOLATED DIURNAL CONVECTION WILL
DEVELOP SATURDAY AFTERNOON...AS MID-LEVEL CAP REMAINS MARGINAL.
WILL CONTINUE TO FEATURE SLIGHT CHANCE POPS ACCORDINGLY. AS CAP
STRENGTHENS...SUNDAY LOOKS TO BE A SUNNY AND DRY DAY. MAIN STORY
TODAY THROUGH SUNDAY WILL BE THE HEAT. HIGH TEMPS EACH DAY WILL
RISE INTO THE LOWER 90S...WHILE OVERNIGHT LOWS ONLY DROP INTO THE
LOWER 70S. THESE TEMPERATURES COMBINED WITH DEWPOINTS IN THE UPPER
60S AND LOWER 70S...WILL PRODUCE AFTERNOON HEAT INDEX READINGS OF
95 TO 100 DEGREES.
LONG TERM...MONDAY THROUGH THURSDAY
UPPER RIDGE WILL GRADUALLY RETROGRADE WESTWARD NEXT WEEK...WITH
BOTH THE GFS AND ECMWF SHOWING RIDGE BUILDING OVER THE ROCKIES BY
WEDNESDAY/THURSDAY. AS A RESULT...INCREASING NORTHWESTERLY FLOW
DOWNSTREAM FROM THE RIDGE WILL PUSH A COLD FRONT INTO ILLINOIS BY
THE MIDDLE OF THE WEEK. MODELS STILL EXHIBIT A BIT OF A SPREAD IN
SOLUTIONS...BUT GENERAL CONSENSUS BRINGS FRONT INTO THE AREA BY
WEDNESDAY NIGHT/THURSDAY. HAVE INTRODUCED CHANCE POPS ACROSS THE
NORTHERN CWA ON WEDNESDAY...THEN EVERYWHERE WEDNESDAY NIGHT INTO
THURSDAY. ONCE FRONT PASSES...COOLER AND LESS HUMID WEATHER WILL
ARRIVE BY THE END OF NEXT WEEK.
BARNES
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1000 AM CDT FRI JUN 21 2013
.MESOSCALE DISCUSSION...
1000 AM CDT
COMPLEX OF STORMS CONTINUES TO EVOLVE ACROSS SOUTHERN WI/FAR NW
IL/NE IA. LATEST RADAR TRENDS SHOW REFLECTIVITY WEAKENING TOWARD
THE DBQ AREA WITH A MORE PERSISTENT LINE NOW SET UP FROM SOUTHERN
CENTRAL WI BACK TO FREEPORT AND SAVANNA MOVING EASTWARD. THE
ATMOSPHERE AHEAD OF THIS ACROSS THE LOCAL AREA IS STILL CAPPED AND
THE COMPLEX IS BEGINNING TO OUTRUN BETTER DEEP LAYER SHEAR. SOME
OUTFLOW IS PRESENT BASED ON SFC OBS SHIFTING WINDS TO THE
NORTHWEST WITH SOME GUSTINESS BUT THE LINE MAY BE BECOMING
ELEVATED. THAT SAID...WINDS SOUTH OF THE LINE HAVE TURNED MORE
SOUTH-SOUTHWEST HELPING TO FEED SLIGHTLY HIGHER DEWPOINT AIR
NORTHWARD. HOWEVER...IT DOES LOOK TO BE A FEW MORE HOURS BEFORE
CAPPING CAN ERODE WHICH WOULD LIKELY BE TOO LATE TO INTERSECT WITH
CURRENT STORMS. AT THIS POINT EXPECT THE BEST COVERAGE OF STORMS
TO MOVE EAST OR EAST-SOUTHEAST ALONG A LINE FROM FREEPORT TO
CHICAGO THOUGH THE SOUTHERN END OF THE LINE MAY BE MORE VARIABLE
IN COVERAGE. HEAVY DOWNPOURS WILL OCCUR AND THE LATEST RADAR SCANS
HAVE SHOWN A SLOWING TREND SO LOCALIZED FLOODING IS A THREAT WITH
1 INCH+ PER HOUR RAINFALL RATES LIKELY BASED ON UPSTREAM REPORTS.
AN ISOLATED STRONG/SEVERE WIND THREAT EXISTS MAINLY IF CAPPING CAN
ERODE. A BOUNDARY MAY LAY OUT ACROSS THE AREA THANKS TO THIS
ACTIVITY LEADING TO AT LEAST A LOW CHANCE FOR NEW DEVELOPMENT
LATER TODAY.
MDB
&&
.DISCUSSION...
329 AM CDT
THE MAIN FORECAST CHALLENGE FOR THE SHORT TERM WILL BE THE EVOLUTION
OF THE MCS OVER THE UPPER MS VALLEY TODAY. THIS COULD BE FOLLOWED
BY ADDITIONAL STORM CLUSTERS THROUGH SATURDAY...AND AGAIN MONDAY
THROUGH WEDNESDAY. ALSO THE BUILDING HEAT AND HUMIDITY THROUGH
THE MIDDLE OF NEXT WEEK.
IN THE SHORT TERM A NARROW BAND OF SHOWERS AND WEAK THUNDERSTORMS
EXTENDS FROM WESTERN WI TO THE IL/IA BORDER. THIS ACTIVITY OCCURRING
ALONG AN AXIS OF HIGHER LOW LEVEL MOISTURE AND THE EASTERN EDGE OF
THE LOW LEVEL JET. EXPECT THIS ACTIVITY TO WEAKEN AND DIE EARLY THIS
MORNING AS IT MOVES INTO DRIER AND MORE STABLE ATMOSPHERE. HAVE SOME
LOW POPS FOR FAR WESTERN COUNTIES THROUGH MID MORNING. MEANWHILE
VERY ACTIVE MCS OVER MN DIVING SOUTHEAST. THIS ACTIVITY SHOULD BE
ON A DIURNALLY WEAKENING TREND LATER THIS MORNING. MEAN MID AND
UPPER LEVEL WINDS ARE WESTERLY WITH FLAT RIDGE ACROSS THE UPPER MS
VALLEY AND GREAT LAKES...WHICH MIGHT SUGGEST THIS WILL REMAIN
MAINLY NORTH OVER WISCONSIN...BUT ACTIVITY IS DROPPING SOUTHEAST
AS CONVECTION BACK BUILDS INTO LOW LEVEL JET. IF IT HOLDS
TOGETHER ON ITS PRESENT COURSE...IT WILL BE APPROACHING NORTHWEST
AND NORTH CENTRAL IL BY LATE MORNING. HRRR SEEMS TO BE THE MOST
AGGRESSIVE OF THE SHORT TERM GUIDANCE IN BRINGING PRECIP INTO
NORTHERN IL TODAY. DEEP LAYER SHEAR WILL BE LACKING THIS FAR
SOUTH BUT WITH BUILDING HEAT AND SURFACE DEW POINTS CLIMBING INTO
THE MID AND UPPER 60S...THERE MAY BE SUFFICIENT LOW LEVEL
INSTABILITY FOR STORMS TO CONTINUE SOUTHEASTWARD INTO IL. HAVE
MAINTAINED 30-40 PERCENT POPS MAINLY FOR NORTHERN COUPLE OF TIERS
OF COUNTIES. SPC HAS MUCH OF NORTHERN IL IN SLIGHT RISK FOR WIND
AND HAIL THREAT. THE ASSOCIATED CIRRUS SHIELD MAY ALSO IMPACT
TEMPERATURES. THEREFORE HAVE LOWERED MAX TEMPS ACROSS THE FAR NORTH
DOWN A COUPLE DEGREES TO THE MID 80S WHILE KEEPING MAX TEMPS IN
UPPER 80S TO NEAR 90 FURTHER SOUTH. EXPECT SOUTH WINDS TO BE
SUFFICIENTLY STRONG TO PREVENT A LAKE BREEZE. ALTHOUGH WITH SOUTH
TO SLIGHTLY EAST OF SOUTH WINDS...A WEAK LAKE BREEZE MAY DRIFT
ONSHORE ACROSS NORTHERN COOK AND LAKE COUNTY IN THIS AFTERNOON.
ANOTHER MCS MAY DEVELOP AND MOVE THROUGH THE NORTHERN PART OF THE
FORECAST AREA AGAIN SATURDAY AS A SERIES OF WEAK WAVES MOVES THROUGH
THE RING OF FIRE ACROSS THE GREAT LAKES. BUT LOW CONFIDENCE THIS FAR
OUT. THE GENERAL TREND OF THE MODELS IS TO SLOWLY BUILD THE RIDGE
INTO THE WESTERN GREAT LAKES OVER THE WEEKEND. THEREFORE HAVE JUST
LOW CHANCE POPS FOR SATURDAY AND A DRY FORECAST FOR SUNDAY. MONDAY
THROUGH WEDNESDAY A SERIES OF WAVES SUPPRESSES THE RIDGE...WHICH
EVENTUALLY RE-ESTABLISHES ITSELF OVER THE WESTERN US. BY THE END
OF THE WEEK MODELS IN DECENT AGREEMENT IN DEVELOPING AN UPPER LOW
OVER THE GREAT LAKES.
MAX TEMPERATURES EXPECTED TO BE IN THE UPPER 80S TO AROUND 90 TODAY
THROUGH WEDNESDAY...WITH DEW POINTS IN THE UPPER 60S TO AROUND 70.
THIS PRODUCES HEAT INDEX VALUES IN MID TO UPPER 90S. THIS IS
BELOW LOCAL HEAT ADVISORY THRESHOLDS. HOWEVER SEEING AS THIS IS
THE FIRST HEAT WAVE OF THE SUMMER AND IT MAY PERSIST FOR SEVERAL
DAYS. A HEAT ADVISORY MAY NEED TO BE CONSIDERED BY EARLY TO MID
WEEK. ANY THUNDERSTORMS AND ASSOCIATED CLOUD COVER/OUTFLOW
BOUNDARIES MAY TEMPORARILY COOL THINGS DOWN AND IMPACT ANY FUTURE
DECISIONS ON HEAT HEADLINES.
PATTERN LOOKS TO BECOME MUCH COOLER NEXT WEEKEND.
ALLSOPP
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* TS POTENTIAL TOWARD 17Z.
* VARIABLE WIND DIRECTION POSSIBLE 17-18 OR 19Z THANKS TO TS
ACTIVITY.
MDB
//DISCUSSION...UPDATED 14Z...
COMPLEX OF TS CONTINUES TO MOVE SOUTH AND EAST ACROSS SW WI AND NE
IA. BEST ESTIMATE IS THAT THE ACTIVITY WILL REMAIN MOST FOCUSED
NORTH AND WEST OF THE TERMINALS THROUGH MIDDAY...BUT RFD WILL
LIKELY SEE A PERIOD OF STORMS TOWARD 15-1530Z BRINGING A SHIFT TO
NORTH OR NORTHWEST WINDS BEFORE THEY SHIFT BACK TO THE SOUTHEAST.
WILL CONTINUE TO MONITOR TRENDS FOR DPA/ORD/MDW BUT THE FAVORED
TIME OF ACTIVITY IS APPROX 17Z REGARDLESS OF COVERAGE/INTENSITY.
THE COMPLEX CONTINUES TO EVOLVE WITH SOME DECAY OCCURRING NEAR
DBQ. A DOMINANT LINE MAY RESULT THAT RIDES FROM FEP TO ORD/MDW
WITH ANOTHER AREA REMAINING FOCUSED NEAR THE MS RIVER. ADDITIONAL
TAF ADJUSTMENTS MAY BE NEEDED PRIOR TO 16Z. STORMS SHOULD LAST
APPROX AN HOUR OR SO WITH SOME EMBEDDED TS BEHIND THE MAIN LINE
LINGERING FOR ANOTHER HOUR OR TWO. LOW POTENTIAL FOR ADDITIONAL
ACTIVITY CONTINUES LATER THIS AFTERNOON AND EVENING BUT PROB IS
TOO LOW TO INCLUDE IN TAF FOR NOW.
MDB
FROM 12Z...
LARGE COMPLEX OF THUNDERSTORMS OVER THE UPPER MIDWEST EARLY THIS
MORNING WAS SLOWLY SLIDING SOUTHEAST. REGIONAL RADAR INDICATED A
LINE OF THUNDERSTORMS STLL ASSOCIATED WITH THIS COMPLEX
STRETCHING FROM FAR NORTHEAST IOWA INTO WEST CENTRAL WISCONSIN.
GUIDANCE INDICATES THAT THIS LINE WILL BEGIN TO WEAKEN AS IT
CONTINUES TO SLIDES SOUTHEAST. CURRENT THINKING IS THAT SOME
REMNANTS OF THIS LINE OF THUNDERSTORMS MAY ARRIVE LATER THIS
MORNING. THE TIMING WOULD BE INTO RFD ARND 16Z THEN FURTHER EAST
AT ORD/MDW/DPA/GYY CLOSER TO 18Z ARRIVAL. WITH SOME HEATING AHEAD
OF THIS LINE OVER NORTHERN IL/NORTHWEST IN AIRFIELDS...THIS MAY
AID IN MAINTAINING THIS LINE OF CONVECTION. AT THIS TIME HAVE
OPTED TO GO WITH A VCTS RATHER THAN A PREVAILING MENTION. BUT THAT
MAY NEED TO BE CHANGED FOR THE 14Z AMD.
SOUTHERLY WINDS WILL CONTINUE THRU MUCH OF THE DAY WITH OCCASIONAL
GUSTS BEGINNING TO OCCUR LATER THIS MORNING TO AROUND 20 KT.
CLOUD DECKS SHUD BE AROUND 5KFT AGL...AND MAY SLOWLY GROW IN
COVERAGE THROUGHOUT THE AFT FROM A SCT TO BKN. GUIDANCE IS THEN
REDEVELOPING A LINE OF SHOWERS/THUNDERSTORMS LATE THIS AFTN/EVE
ALONG A REMNANT BOUNDARY FROM THIS MORNING CONVECTION. SOME OF
THESE THUNDERSTORMS COULD BE STRONG TO SEVERE...WITH THE MAIN HAZARDS
BEING WIND/HAIL.
SOUTHERLY WINDS PERSIST OVERNIGHT AND DIMINISH TO ARND 10KT...WITH
SOME TURNING TO THE SOUTHWEST EXPECTED OVERNIGHT TOWARDS DAYBREAK
SAT. OVERALL EXPECT VFR CONDS THROUGHOUT...HOWEVER WITH ANY
THUNDERSTORM ACTIVITY THIS COULD EASILY BE LIMITED TO MVFR.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* MEDIUM CONFIDENCE IN AT LEAST SOME TS ACTIVITY NEAR THE
TERMINALS BY 17/18Z OR SO.
* MEDIUM CONFIDENCE IN VARIABLE/ERRATIC WINDS DEVELOPING WITH TS
ACTIVITY TOWARD 17/18Z
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...VFR.
SUNDAY...MAINLY VFR. CHC THUNDERSTORMS LATE.
MONDAY THROUGH THURSDAY...PERIODIC CHANCES FOR THUNDERSTORMS.
OTHERWISE VFR.
BEACHLER
&&
.MARINE...
240 AM CDT
MAIN CONCERN FOR LAKE MICHIGAN WILL BE POTENTIAL FOR FOG
DEVELOPMENT AND TIMING...ALONG WITH CHANCES FOR THUNDERSTORMS. AT
THIS TIME THERE DOES NOT APPEAR TO BE ANY WIND/WAVE HAZARDS
EXPECTED IN THE NEXT SEVERAL DAYS.
HIGH PRESURE ANCHORED ACROSS THE WESTERN ATLANTIC OCEAN ALONG WITH
A BROAD LOW PRESSURE ANCHORED OVER THE CENTRAL PLAINS...WILL
MAINTAIN THE SOUTHERLY FLOW OVER THE LAKE. IN ADDITION VERY WARM
AIR WILL SLIDE OVER THE COOLER OPEN WATERS OF THE LAKE...AND HELP
TO KEEP WAVES FROM BUILDING TO LARGE. THE GRADIENT THIS AFTERNOON
DOES INCREASE WHICH MAY ALLOW WINDS TO INCREASE TO AROUND 20-25KT
FOR THE NORTHERN HALF OF THE LAKE...HOWEVER WAVES SHOULD ONLY
BUILD TO 2 TO 4 FT. AT TIMES WINDS MAY GUST TO 25 KT FURTHER SOUTH
THIS AFTERNOON. THUNDERSTORMS ARE FORECAST FOR THE NEXT SEVERAL
DAYS...HOWEVER THESE DO NOT APPEAR TO BE AN ALL DAY OR NIGHT
THING. BUT WINDS/WAVES WILL BE HIGHER IN AND AROUND ANY
THUNDERSTORMS THAT DO SLIDE ACROSS THE LAKE.
AS MENTIONED EARLIER ABOUT THE FOG DEVELOPMENT. IT DOES APPEAR
THAT WITH ENOUGH WIND THIS AFTERNOON FOG WILL HOLD OFF UNTIL
PERHAPS LATE TONIGHT OR POSSIBLY SATURDAY. A WARM FRONT WILL LIFT
NORTH OVER THE LAKE...WITH FOG DEVELOPMENT EXPECTED JUST AFTER
PASSAGE. THIS STILL APPEARS TO FAVOR THE NORTHERN PORTIONS OF THE
LAKE AND AT TIMES COULD BE DENSE. ONCE FOG DEVELOPS IT COULD
EASILY LINGER THROUGH EARLY NEXT WEEK AS THE WINDS ARE NOT
EXPECTED TO BE VERY STRONG.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
935 AM CDT FRI JUN 21 2013
.DISCUSSION...
329 AM CDT
THE MAIN FORECAST CHALLENGE FOR THE SHORT TERM WILL BE THE EVOLUTION
OF THE MCS OVER THE UPPER MS VALLEY TODAY. THIS COULD BE FOLLOWED
BY ADDITIONAL STORM CLUSTERS THROUGH SATURDAY...AND AGAIN MONDAY
THROUGH WEDNESDAY. ALSO THE BUILDING HEAT AND HUMIDITY THROUGH
THE MIDDLE OF NEXT WEEK.
IN THE SHORT TERM A NARROW BAND OF SHOWERS AND WEAK THUNDERSTORMS
EXTENDS FROM WESTERN WI TO THE IL/IA BORDER. THIS ACTIVITY OCCURRING
ALONG AN AXIS OF HIGHER LOW LEVEL MOISTURE AND THE EASTERN EDGE OF
THE LOW LEVEL JET. EXPECT THIS ACTIVITY TO WEAKEN AND DIE EARLY THIS
MORNING AS IT MOVES INTO DRIER AND MORE STABLE ATMOSPHERE. HAVE SOME
LOW POPS FOR FAR WESTERN COUNTIES THROUGH MID MORNING. MEANWHILE
VERY ACTIVE MCS OVER MN DIVING SOUTHEAST. THIS ACTIVITY SHOULD BE
ON A DIURNALLY WEAKENING TREND LATER THIS MORNING. MEAN MID AND
UPPER LEVEL WINDS ARE WESTERLY WITH FLAT RIDGE ACROSS THE UPPER MS
VALLEY AND GREAT LAKES...WHICH MIGHT SUGGEST THIS WILL REMAIN
MAINLY NORTH OVER WISCONSIN...BUT ACTIVITY IS DROPPING SOUTHEAST
AS CONVECTION BACK BUILDS INTO LOW LEVEL JET. IF IT HOLDS
TOGETHER ON ITS PRESENT COURSE...IT WILL BE APPROACHING NORTHWEST
AND NORTH CENTRAL IL BY LATE MORNING. HRRR SEEMS TO BE THE MOST
AGGRESSIVE OF THE SHORT TERM GUIDANCE IN BRINGING PRECIP INTO
NORTHERN IL TODAY. DEEP LAYER SHEAR WILL BE LACKING THIS FAR
SOUTH BUT WITH BUILDING HEAT AND SURFACE DEW POINTS CLIMBING INTO
THE MID AND UPPER 60S...THERE MAY BE SUFFICIENT LOW LEVEL
INSTABILITY FOR STORMS TO CONTINUE SOUTHEASTWARD INTO IL. HAVE
MAINTAINED 30-40 PERCENT POPS MAINLY FOR NORTHERN COUPLE OF TIERS
OF COUNTIES. SPC HAS MUCH OF NORTHERN IL IN SLIGHT RISK FOR WIND
AND HAIL THREAT. THE ASSOCIATED CIRRUS SHIELD MAY ALSO IMPACT
TEMPERATURES. THEREFORE HAVE LOWERED MAX TEMPS ACROSS THE FAR NORTH
DOWN A COUPLE DEGREES TO THE MID 80S WHILE KEEPING MAX TEMPS IN
UPPER 80S TO NEAR 90 FURTHER SOUTH. EXPECT SOUTH WINDS TO BE
SUFFICIENTLY STRONG TO PREVENT A LAKE BREEZE. ALTHOUGH WITH SOUTH
TO SLIGHTLY EAST OF SOUTH WINDS...A WEAK LAKE BREEZE MAY DRIFT
ONSHORE ACROSS NORTHERN COOK AND LAKE COUNTY IN THIS AFTERNOON.
ANOTHER MCS MAY DEVELOP AND MOVE THROUGH THE NORTHERN PART OF THE
FORECAST AREA AGAIN SATURDAY AS A SERIES OF WEAK WAVES MOVES THROUGH
THE RING OF FIRE ACROSS THE GREAT LAKES. BUT LOW CONFIDENCE THIS FAR
OUT. THE GENERAL TREND OF THE MODELS IS TO SLOWLY BUILD THE RIDGE
INTO THE WESTERN GREAT LAKES OVER THE WEEKEND. THEREFORE HAVE JUST
LOW CHANCE POPS FOR SATURDAY AND A DRY FORECAST FOR SUNDAY. MONDAY
THROUGH WEDNESDAY A SERIES OF WAVES SUPPRESSES THE RIDGE...WHICH
EVENTUALLY RE-ESTABLISHES ITSELF OVER THE WESTERN US. BY THE END
OF THE WEEK MODELS IN DECENT AGREEMENT IN DEVELOPING AN UPPER LOW
OVER THE GREAT LAKES.
MAX TEMPERATURES EXPECTED TO BE IN THE UPPER 80S TO AROUND 90 TODAY
THROUGH WEDNESDAY...WITH DEW POINTS IN THE UPPER 60S TO AROUND 70.
THIS PRODUCES HEAT INDEX VALUES IN MID TO UPPER 90S. THIS IS
BELOW LOCAL HEAT ADVISORY THRESHOLDS. HOWEVER SEEING AS THIS IS
THE FIRST HEAT WAVE OF THE SUMMER AND IT MAY PERSIST FOR SEVERAL
DAYS. A HEAT ADVISORY MAY NEED TO BE CONSIDERED BY EARLY TO MID
WEEK. ANY THUNDERSTORMS AND ASSOCIATED CLOUD COVER/OUTFLOW
BOUNDARIES MAY TEMPORARILY COOL THINGS DOWN AND IMPACT ANY FUTURE
DECISIONS ON HEAT HEADLINES.
PATTERN LOOKS TO BECOME MUCH COOLER NEXT WEEKEND.
ALLSOPP
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* TS POTENTIAL TOWARD 17Z.
* VARIABLE WIND DIRECTION POSSIBLE 17-18 OR 19Z THANKS TO TS
ACTIVITY.
MDB
//DISCUSSION...UPDATED 14Z...
COMPLEX OF TS CONTINUES TO MOVE SOUTH AND EAST ACROSS SW WI AND NE
IA. BEST ESTIMATE IS THAT THE ACTIVITY WILL REMAIN MOST FOCUSED
NORTH AND WEST OF THE TERMINALS THROUGH MIDDAY...BUT RFD WILL
LIKELY SEE A PERIOD OF STORMS TOWARD 15-1530Z BRINGING A SHIFT TO
NORTH OR NORTHWEST WINDS BEFORE THEY SHIFT BACK TO THE SOUTHEAST.
WILL CONTINUE TO MONITOR TRENDS FOR DPA/ORD/MDW BUT THE FAVORED
TIME OF ACTIVITY IS APPROX 17Z REGARDLESS OF COVERAGE/INTENSITY.
THE COMPLEX CONTINUES TO EVOLVE WITH SOME DECAY OCCURRING NEAR
DBQ. A DOMINANT LINE MAY RESULT THAT RIDES FROM FEP TO ORD/MDW
WITH ANOTHER AREA REMAINING FOCUSED NEAR THE MS RIVER. ADDITIONAL
TAF ADJUSTMENTS MAY BE NEEDED PRIOR TO 16Z. STORMS SHOULD LAST
APPROX AN HOUR OR SO WITH SOME EMBEDDED TS BEHIND THE MAIN LINE
LINGERING FOR ANOTHER HOUR OR TWO. LOW POTENTIAL FOR ADDITIONAL
ACTIVITY CONTINUES LATER THIS AFTERNOON AND EVENING BUT PROB IS
TOO LOW TO INCLUDE IN TAF FOR NOW.
MDB
FROM 12Z...
LARGE COMPLEX OF THUNDERSTORMS OVER THE UPPER MIDWEST EARLY THIS
MORNING WAS SLOWLY SLIDING SOUTHEAST. REGIONAL RADAR INDICATED A
LINE OF THUNDERSTORMS STLL ASSOCIATED WITH THIS COMPLEX
STRETCHING FROM FAR NORTHEAST IOWA INTO WEST CENTRAL WISCONSIN.
GUIDANCE INDICATES THAT THIS LINE WILL BEGIN TO WEAKEN AS IT
CONTINUES TO SLIDES SOUTHEAST. CURRENT THINKING IS THAT SOME
REMNANTS OF THIS LINE OF THUNDERSTORMS MAY ARRIVE LATER THIS
MORNING. THE TIMING WOULD BE INTO RFD ARND 16Z THEN FURTHER EAST
AT ORD/MDW/DPA/GYY CLOSER TO 18Z ARRIVAL. WITH SOME HEATING AHEAD
OF THIS LINE OVER NORTHERN IL/NORTHWEST IN AIRFIELDS...THIS MAY
AID IN MAINTAINING THIS LINE OF CONVECTION. AT THIS TIME HAVE
OPTED TO GO WITH A VCTS RATHER THAN A PREVAILING MENTION. BUT THAT
MAY NEED TO BE CHANGED FOR THE 14Z AMD.
SOUTHERLY WINDS WILL CONTINUE THRU MUCH OF THE DAY WITH OCCASIONAL
GUSTS BEGINNING TO OCCUR LATER THIS MORNING TO AROUND 20 KT.
CLOUD DECKS SHUD BE AROUND 5KFT AGL...AND MAY SLOWLY GROW IN
COVERAGE THROUGHOUT THE AFT FROM A SCT TO BKN. GUIDANCE IS THEN
REDEVELOPING A LINE OF SHOWERS/THUNDERSTORMS LATE THIS AFTN/EVE
ALONG A REMNANT BOUNDARY FROM THIS MORNING CONVECTION. SOME OF
THESE THUNDERSTORMS COULD BE STRONG TO SEVERE...WITH THE MAIN HAZARDS
BEING WIND/HAIL.
SOUTHERLY WINDS PERSIST OVERNIGHT AND DIMINISH TO ARND 10KT...WITH
SOME TURNING TO THE SOUTHWEST EXPECTED OVERNIGHT TOWARDS DAYBREAK
SAT. OVERALL EXPECT VFR CONDS THROUGHOUT...HOWEVER WITH ANY
THUNDERSTORM ACTIVITY THIS COULD EASILY BE LIMITED TO MVFR.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* MEDIUM CONFIDENCE IN AT LEAST SOME TS ACTIVITY NEAR THE
TERMINALS BY 17/18Z OR SO.
* MEDIUM CONFIDENCE IN VARIABLE/ERRATIC WINDS DEVELOPING WITH TS
ACTIVITY TOWARD 17/18Z
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...VFR.
SUNDAY...MAINLY VFR. CHC THUNDERSTORMS LATE.
MONDAY THROUGH THURSDAY...PERIODIC CHANCES FOR THUNDERSTORMS.
OTHERWISE VFR.
BEACHLER
&&
.MARINE...
240 AM CDT
MAIN CONCERN FOR LAKE MICHIGAN WILL BE POTENTIAL FOR FOG
DEVELOPMENT AND TIMING...ALONG WITH CHANCES FOR THUNDERSTORMS. AT
THIS TIME THERE DOES NOT APPEAR TO BE ANY WIND/WAVE HAZARDS
EXPECTED IN THE NEXT SEVERAL DAYS.
HIGH PRESURE ANCHORED ACROSS THE WESTERN ATLANTIC OCEAN ALONG WITH
A BROAD LOW PRESSURE ANCHORED OVER THE CENTRAL PLAINS...WILL
MAINTAIN THE SOUTHERLY FLOW OVER THE LAKE. IN ADDITION VERY WARM
AIR WILL SLIDE OVER THE COOLER OPEN WATERS OF THE LAKE...AND HELP
TO KEEP WAVES FROM BUILDING TO LARGE. THE GRADIENT THIS AFTERNOON
DOES INCREASE WHICH MAY ALLOW WINDS TO INCREASE TO AROUND 20-25KT
FOR THE NORTHERN HALF OF THE LAKE...HOWEVER WAVES SHOULD ONLY
BUILD TO 2 TO 4 FT. AT TIMES WINDS MAY GUST TO 25 KT FURTHER SOUTH
THIS AFTERNOON. THUNDERSTORMS ARE FORECAST FOR THE NEXT SEVERAL
DAYS...HOWEVER THESE DO NOT APPEAR TO BE AN ALL DAY OR NIGHT
THING. BUT WINDS/WAVES WILL BE HIGHER IN AND AROUND ANY
THUNDERSTORMS THAT DO SLIDE ACROSS THE LAKE.
AS MENTIONED EARLIER ABOUT THE FOG DEVELOPMENT. IT DOES APPEAR
THAT WITH ENOUGH WIND THIS AFTERNOON FOG WILL HOLD OFF UNTIL
PERHAPS LATE TONIGHT OR POSSIBLY SATURDAY. A WARM FRONT WILL LIFT
NORTH OVER THE LAKE...WITH FOG DEVELOPMENT EXPECTED JUST AFTER
PASSAGE. THIS STILL APPEARS TO FAVOR THE NORTHERN PORTIONS OF THE
LAKE AND AT TIMES COULD BE DENSE. ONCE FOG DEVELOPS IT COULD
EASILY LINGER THROUGH EARLY NEXT WEEK AS THE WINDS ARE NOT
EXPECTED TO BE VERY STRONG.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS LINCOLN IL
700 AM CDT FRI JUN 21 2013
.DISCUSSION...
ISSUED 256 AM CDT FRI JUN 21 2013
QUIET SUMMER-LIKE WEATHER WILL PREVAIL FOR SEVERAL DAYS...WITH
THE NEXT SIGNIFICANT CHANCE FOR RAIN HOLDING OFF UNTIL THE MIDDLE
OF NEXT WEEK.
SHORT TERM...TODAY THROUGH SUNDAY
MCS CURRENTLY ACROSS MINNESOTA WILL TRACK E/SE INTO WISCONSIN
THIS MORNING...REMAINING WELL NORTH OF CENTRAL ILLINOIS. FURTHER
SOUTH BENEATH THE BUILDING UPPER-LEVEL RIDGE...A WEAK FRONTAL
BOUNDARY IS SETTING OFF WIDELY SCATTERED SHOWERS/THUNDER ACROSS
EASTERN IOWA AND WESTERN ILLINOIS. THINK THIS SUBTLE BOUNDARY WILL
CONTINUE TO BE THE MAIN FOCUSING MECHANISM FOR ADDITIONAL
CONVECTION THROUGHOUT THE DAY. DUE TO LACK OF UPPER SUPPORT AND
WARMING MID-LEVELS BENEATH THE RIDGE...WIDESPREAD CONVECTION WILL
REMAIN UNLIKELY. WILL CARRY 20 POPS ALONG AND WEST OF I-55 IN
CLOSE PROXIMITY TO THE FRONT...WITH DRY WEATHER FURTHER EAST AND
SOUTH. WILL BE A VERY WARM/HUMID DAY AS WELL...WITH AFTERNOON
HIGHS REACHING THE LOWER 90S.
MODELS CONTINUE TO SUGGEST ISOLATED DIURNAL CONVECTION WILL
DEVELOP SATURDAY AFTERNOON...AS MID-LEVEL CAP REMAINS MARGINAL.
WILL CONTINUE TO FEATURE SLIGHT CHANCE POPS ACCORDINGLY. AS CAP
STRENGTHENS...SUNDAY LOOKS TO BE A SUNNY AND DRY DAY. MAIN STORY
TODAY THROUGH SUNDAY WILL BE THE HEAT. HIGH TEMPS EACH DAY WILL
RISE INTO THE LOWER 90S...WHILE OVERNIGHT LOWS ONLY DROP INTO THE
LOWER 70S. THESE TEMPERATURES COMBINED WITH DEWPOINTS IN THE UPPER
60S AND LOWER 70S...WILL PRODUCE AFTERNOON HEAT INDEX READINGS OF
95 TO 100 DEGREES.
LONG TERM...MONDAY THROUGH THURSDAY
UPPER RIDGE WILL GRADUALLY RETROGRADE WESTWARD NEXT WEEK...WITH
BOTH THE GFS AND ECMWF SHOWING RIDGE BUILDING OVER THE ROCKIES BY
WEDNESDAY/THURSDAY. AS A RESULT...INCREASING NORTHWESTERLY FLOW
DOWNSTREAM FROM THE RIDGE WILL PUSH A COLD FRONT INTO ILLINOIS BY
THE MIDDLE OF THE WEEK. MODELS STILL EXHIBIT A BIT OF A SPREAD IN
SOLUTIONS...BUT GENERAL CONSENSUS BRINGS FRONT INTO THE AREA BY
WEDNESDAY NIGHT/THURSDAY. HAVE INTRODUCED CHANCE POPS ACROSS THE
NORTHERN CWA ON WEDNESDAY...THEN EVERYWHERE WEDNESDAY NIGHT INTO
THURSDAY. ONCE FRONT PASSES...COOLER AND LESS HUMID WEATHER WILL
ARRIVE BY THE END OF NEXT WEEK.
BARNES
&&
.AVIATION...
ISSUED 655 AM CDT FRI JUN 21 2013
1027 MB HIGH PRESSURE OFF THE MID ATLANTIC COAST AND RIDGING
WESTWARD INTO THE OHIO VALLEY TO BE NEARLY STATIONARY INTO SAT
MORNING WHILE 1003 MB LOW PRESSUE OVER EASTERN CO INTO SW NEBRASKA
WITH FRONTAL BOUNDARY EXTENDING NE INTO SOUTHERN MN TO ALSO REMAIN
IN PLACE NEXT 24 HOURS. VFR CONDITIONS SHOULD CONTINUE ACROSS THE
CENTRAL IL TERMINAL AIRPORTS NEXT 24 HOURS THROUGH 12Z/7 AM SAT.
SCATTERED TO BROKEN MID/HIGH CLOUDS TO SPREAD SE FROM THE IL RIVER
ACROSS CENTRAL IL DURING TODAY AS SCATTERED CUMULUS CLOUDS WITH
BASES OF 4-6K FT DEVELOP AFTER 15Z/10 AM. CURULE FROM RUC MODEL
SHOWS BROKEN CUMULUS CEILINGS NORTH AND SOUTH OF CENTRAL IL THIS
AFTERNOON. HAVE VCSH AT PIA OVER IL RIVER VALLEY THIS AFTERNOON
AFTER 18Z/1 PM BUT BETTER CHANCE OF CONVECTION WILL BE NW TOWARD
IA. FEW TO SCATTERED CLOUDS LINGER TONIGHT. SOUTH WINDS 10-15 KTS
WITH GUSTS AROUND 20 KTS AFTER 15Z/10 AM TODAY AND DIMINISH TO
5-10 KTS AFTER SUNSET.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
637 AM CDT FRI JUN 21 2013
.DISCUSSION...
329 AM CDT
THE MAIN FORECAST CHALLENGE FOR THE SHORT TERM WILL BE THE EVOLUTION
OF THE MCS OVER THE UPPER MS VALLEY TODAY. THIS COULD BE FOLLOWED
BY ADDITIONAL STORM CLUSTERS THROUGH SATURDAY...AND AGAIN MONDAY
THROUGH WEDNESDAY. ALSO THE BUILDING HEAT AND HUMIDITY THROUGH
THE MIDDLE OF NEXT WEEK.
IN THE SHORT TERM A NARROW BAND OF SHOWERS AND WEAK THUNDERSTORMS
EXTENDS FROM WESTERN WI TO THE IL/IA BORDER. THIS ACTIVITY OCCURRING
ALONG AN AXIS OF HIGHER LOW LEVEL MOISTURE AND THE EASTERN EDGE OF
THE LOW LEVEL JET. EXPECT THIS ACTIVITY TO WEAKEN AND DIE EARLY THIS
MORNING AS IT MOVES INTO DRIER AND MORE STABLE ATMOSPHERE. HAVE SOME
LOW POPS FOR FAR WESTERN COUNTIES THROUGH MID MORNING. MEANWHILE
VERY ACTIVE MCS OVER MN DIVING SOUTHEAST. THIS ACTIVITY SHOULD BE
ON A DIURNALLY WEAKENING TREND LATER THIS MORNING. MEAN MID AND
UPPER LEVEL WINDS ARE WESTERLY WITH FLAT RIDGE ACROSS THE UPPER MS
VALLEY AND GREAT LAKES...WHICH MIGHT SUGGEST THIS WILL REMAIN
MAINLY NORTH OVER WISCONSIN...BUT ACTIVITY IS DROPPING SOUTHEAST
AS CONVECTION BACK BUILDS INTO LOW LEVEL JET. IF IT HOLDS
TOGETHER ON ITS PRESENT COURSE...IT WILL BE APPROACHING NORTHWEST
AND NORTH CENTRAL IL BY LATE MORNING. HRRR SEEMS TO BE THE MOST
AGGRESSIVE OF THE SHORT TERM GUIDANCE IN BRINGING PRECIP INTO
NORTHERN IL TODAY. DEEP LAYER SHEAR WILL BE LACKING THIS FAR
SOUTH BUT WITH BUILDING HEAT AND SURFACE DEW POINTS CLIMBING INTO
THE MID AND UPPER 60S...THERE MAY BE SUFFICIENT LOW LEVEL
INSTABILITY FOR STORMS TO CONTINUE SOUTHEASTWARD INTO IL. HAVE
MAINTAINED 30-40 PERCENT POPS MAINLY FOR NORTHERN COUPLE OF TIERS
OF COUNTIES. SPC HAS MUCH OF NORTHERN IL IN SLIGHT RISK FOR WIND
AND HAIL THREAT. THE ASSOCIATED CIRRUS SHIELD MAY ALSO IMPACT
TEMPERATURES. THEREFORE HAVE LOWERED MAX TEMPS ACROSS THE FAR NORTH
DOWN A COUPLE DEGREES TO THE MID 80S WHILE KEEPING MAX TEMPS IN
UPPER 80S TO NEAR 90 FURTHER SOUTH. EXPECT SOUTH WINDS TO BE
SUFFICIENTLY STRONG TO PREVENT A LAKE BREEZE. ALTHOUGH WITH SOUTH
TO SLIGHTLY EAST OF SOUTH WINDS...A WEAK LAKE BREEZE MAY DRIFT
ONSHORE ACROSS NORTHERN COOK AND LAKE COUNTY IN THIS AFTERNOON.
ANOTHER MCS MAY DEVELOP AND MOVE THROUGH THE NORTHERN PART OF THE
FORECAST AREA AGAIN SATURDAY AS A SERIES OF WEAK WAVES MOVES THROUGH
THE RING OF FIRE ACROSS THE GREAT LAKES. BUT LOW CONFIDENCE THIS FAR
OUT. THE GENERAL TREND OF THE MODELS IS TO SLOWLY BUILD THE RIDGE
INTO THE WESTERN GREAT LAKES OVER THE WEEKEND. THEREFORE HAVE JUST
LOW CHANCE POPS FOR SATURDAY AND A DRY FORECAST FOR SUNDAY. MONDAY
THROUGH WEDNESDAY A SERIES OF WAVES SUPPRESSES THE RIDGE...WHICH
EVENTUALLY RE-ESTABLISHES ITSELF OVER THE WESTERN US. BY THE END
OF THE WEEK MODELS IN DECENT AGREEMENT IN DEVELOPING AN UPPER LOW
OVER THE GREAT LAKES.
MAX TEMPERATURES EXPECTED TO BE IN THE UPPER 80S TO AROUND 90 TODAY
THROUGH WEDNESDAY...WITH DEW POINTS IN THE UPPER 60S TO AROUND 70.
THIS PRODUCES HEAT INDEX VALUES IN MID TO UPPER 90S. THIS IS
BELOW LOCAL HEAT ADVISORY THRESHOLDS. HOWEVER SEEING AS THIS IS
THE FIRST HEAT WAVE OF THE SUMMER AND IT MAY PERSIST FOR SEVERAL
DAYS. A HEAT ADVISORY MAY NEED TO BE CONSIDERED BY EARLY TO MID
WEEK. ANY THUNDERSTORMS AND ASSOCIATED CLOUD COVER/OUTFLOW
BOUNDARIES MAY TEMPORARILY COOL THINGS DOWN AND IMPACT ANY FUTURE
DECISIONS ON HEAT HEADLINES.
PATTERN LOOKS TO BECOME MUCH COOLER NEXT WEEKEND.
ALLSOPP
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* SOUTH WINDS ARND 10 KT WITH OCCASIONAL GUSTS TO 20 KT THIS AFTN.
* POSSIBLE REMNANTS OF THUNDERSTORMS ARRIVING AFT 17Z. THEN
POSSIBLE REDEVELOPMENT OF THUNDERSTORMS LATE THIS AFTN/EVE.
BEACHLER
//DISCUSSION...UPDATED 12Z...
LARGE COMPLEX OF THUNDERSTORMS OVER THE UPPER MIDWEST EARLY THIS
MORNING WAS SLOWLY SLIDING SOUTHEAST. REGIONAL RADAR INDICATED A
LINE OF THUNDERSTORMS STILL ASSOCIATED WITH THIS COMPLEX
STRETCHING FROM FAR NORTHEAST IOWA INTO WEST CENTRAL WISCONSIN.
GUIDANCE INDICATES THAT THIS LINE WILL BEGIN TO WEAKEN AS IT
CONTINUES TO SLIDES SOUTHEAST. CURRENT THINKING IS THAT SOME
REMNANTS OF THIS LINE OF THUNDERSTORMS MAY ARRIVE LATER THIS
MORNING. THE TIMING WOULD BE INTO RFD ARND 16Z THEN FURTHER EAST
AT ORD/MDW/DPA/GYY CLOSER TO 18Z ARRIVAL. WITH SOME HEATING AHEAD
OF THIS LINE OVER NORTHERN IL/NORTHWEST IN AIRFIELDS...THIS MAY
AID IN MAINTAINING THIS LINE OF CONVECTION. AT THIS TIME HAVE
OPTED TO GO WITH A VCTS RATHER THAN A PREVAILING MENTION. BUT THAT
MAY NEED TO BE CHANGED FOR THE 14Z AMD.
SOUTHERLY WINDS WILL CONTINUE THRU MUCH OF THE DAY WITH OCCASIONAL
GUSTS BEGINNING TO OCCUR LATER THIS MORNING TO AROUND 20 KT.
CLOUD DECKS SHUD BE AROUND 5KFT AGL...AND MAY SLOWLY GROW IN
COVERAGE THROUGHOUT THE AFT FROM A SCT TO BKN. GUIDANCE IS THEN
REDEVELOPING A LINE OF SHOWERS/THUNDERSTORMS LATE THIS AFTN/EVE
ALONG A REMNANT BOUNDARY FROM THIS MORNING CONVECTION. SOME OF
THESE THUNDERSTORMS COULD BE STRONG TO SEVERE...WITH THE MAIN HAZARDS
BEING WIND/HAIL.
SOUTHERLY WINDS PERSIST OVERNIGHT AND DIMINISH TO ARND 10KT...WITH
SOME TURNING TO THE SOUTHWEST EXPECTED OVERNIGHT TOWARDS DAYBREAK
SAT. OVERALL EXPECT VFR CONDS THROUGHOUT...HOWEVER WITH ANY
THUNDERSTORM ACTIVITY THIS COULD EASILY BE LIMITED TO MVFR.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* HIGH CONFIDENCE IN WIND DIR/SPEED/GUSTS FORECAST.
* HIGH CONFIDENCE IN OCCASIONAL THUNDERSTORMS.
* LOW CONFIDENCE THAT THUNDERSTORMS WILL DIRECTLY IMPACT
AIRFIELDS.
* MEDIUM CONFIDENCE IN THUNDERSTORM TIMING.
* MEDIUM CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...VFR.
SUNDAY...MAINLY VFR. CHC THUNDERSTORMS LATE.
MONDAY THROUGH THURSDAY...PERIODIC CHANCES FOR THUNDERSTORMS.
OTHERWISE VFR.
BEACHLER
&&
.MARINE...
240 AM CDT
MAIN CONCERN FOR LAKE MICHIGAN WILL BE POTENTIAL FOR FOG
DEVELOPMENT AND TIMING...ALONG WITH CHANCES FOR THUNDERSTORMS. AT
THIS TIME THERE DOES NOT APPEAR TO BE ANY WIND/WAVE HAZARDS
EXPECTED IN THE NEXT SEVERAL DAYS.
HIGH PRESURE ANCHORED ACROSS THE WESTERN ATLANTIC OCEAN ALONG WITH
A BROAD LOW PRESSURE ANCHORED OVER THE CENTRAL PLAINS...WILL
MAINTAIN THE SOUTHERLY FLOW OVER THE LAKE. IN ADDITION VERY WARM
AIR WILL SLIDE OVER THE COOLER OPEN WATERS OF THE LAKE...AND HELP
TO KEEP WAVES FROM BUILDING TO LARGE. THE GRADIENT THIS AFTERNOON
DOES INCREASE WHICH MAY ALLOW WINDS TO INCREASE TO AROUND 20-25KT
FOR THE NORTHERN HALF OF THE LAKE...HOWEVER WAVES SHOULD ONLY
BUILD TO 2 TO 4 FT. AT TIMES WINDS MAY GUST TO 25 KT FURTHER SOUTH
THIS AFTERNOON. THUNDERSTORMS ARE FORECAST FOR THE NEXT SEVERAL
DAYS...HOWEVER THESE DO NOT APPEAR TO BE AN ALL DAY OR NIGHT
THING. BUT WINDS/WAVES WILL BE HIGHER IN AND AROUND ANY
THUNDERSTORMS THAT DO SLIDE ACROSS THE LAKE.
AS MENTIONED EARLIER ABOUT THE FOG DEVELOPMENT. IT DOES APPEAR
THAT WITH ENOUGH WIND THIS AFTERNOON FOG WILL HOLD OFF UNTIL
PERHAPS LATE TONIGHT OR POSSIBLY SATURDAY. A WARM FRONT WILL LIFT
NORTH OVER THE LAKE...WITH FOG DEVELOPMENT EXPECTED JUST AFTER
PASSAGE. THIS STILL APPEARS TO FAVOR THE NORTHERN PORTIONS OF THE
LAKE AND AT TIMES COULD BE DENSE. ONCE FOG DEVELOPS IT COULD
EASILY LINGER THROUGH EARLY NEXT WEEK AS THE WINDS ARE NOT
EXPECTED TO BE VERY STRONG.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
408 AM CDT FRI JUN 21 2013
.DISCUSSION...
329 AM CDT
THE MAIN FORECAST CHALLENGE FOR THE SHORT TERM WILL BE THE EVOLUTION
OF THE MCS OVER THE UPPER MS VALLEY TODAY. THIS COULD BE FOLLOWED
BY ADDITIONAL STORM CLUSTERS THROUGH SATURDAY...AND AGAIN MONDAY
THROUGH WEDNESDAY. ALSO THE BUILDING HEAT AND HUMIDITY THROUGH
THE MIDDLE OF NEXT WEEK.
IN THE SHORT TERM A NARROW BAND OF SHOWERS AND WEAK THUNDERSTORMS
EXTENDS FROM WESTERN WI TO THE IL/IA BORDER. THIS ACTIVITY OCCURRING
ALONG AN AXIS OF HIGHER LOW LEVEL MOISTURE AND THE EASTERN EDGE OF
THE LOW LEVEL JET. EXPECT THIS ACTIVITY TO WEAKEN AND DIE EARLY THIS
MORNING AS IT MOVES INTO DRIER AND MORE STABLE ATMOSPHERE. HAVE SOME
LOW POPS FOR FAR WESTERN COUNTIES THROUGH MID MORNING. MEANWHILE
VERY ACTIVE MCS OVER MN DIVING SOUTHEAST. THIS ACTIVITY SHOULD BE
ON A DIURNALLY WEAKENING TREND LATER THIS MORNING. MEAN MID AND
UPPER LEVEL WINDS ARE WESTERLY WITH FLAT RIDGE ACROSS THE UPPER MS
VALLEY AND GREAT LAKES...WHICH MIGHT SUGGEST THIS WILL REMAIN
MAINLY NORTH OVER WISCONSIN...BUT ACTIVITY IS DROPPING SOUTHEAST
AS CONVECTION BACK BUILDS INTO LOW LEVEL JET. IF IT HOLDS
TOGETHER ON ITS PRESENT COURSE...IT WILL BE APPROACHING NORTHWEST
AND NORTH CENTRAL IL BY LATE MORNING. HRRR SEEMS TO BE THE MOST
AGGRESSIVE OF THE SHORT TERM GUIDANCE IN BRINGING PRECIP INTO
NORTHERN IL TODAY. DEEP LAYER SHEAR WILL BE LACKING THIS FAR
SOUTH BUT WITH BUILDING HEAT AND SURFACE DEW POINTS CLIMBING INTO
THE MID AND UPPER 60S...THERE MAY BE SUFFICIENT LOW LEVEL
INSTABILITY FOR STORMS TO CONTINUE SOUTHEASTWARD INTO IL. HAVE
MAINTAINED 30-40 PERCENT POPS MAINLY FOR NORTHERN COUPLE OF TIERS
OF COUNTIES. SPC HAS MUCH OF NORTHERN IL IN SLIGHT RISK FOR WIND
AND HAIL THREAT. THE ASSOCIATED CIRRUS SHIELD MAY ALSO IMPACT
TEMPERATURES. THEREFORE HAVE LOWERED MAX TEMPS ACROSS THE FAR NORTH
DOWN A COUPLE DEGREES TO THE MID 80S WHILE KEEPING MAX TEMPS IN
UPPER 80S TO NEAR 90 FURTHER SOUTH. EXPECT SOUTH WINDS TO BE
SUFFICIENTLY STRONG TO PREVENT A LAKE BREEZE. ALTHOUGH WITH SOUTH
TO SLIGHTLY EAST OF SOUTH WINDS...A WEAK LAKE BREEZE MAY DRIFT
ONSHORE ACROSS NORTHERN COOK AND LAKE COUNTY IN THIS AFTERNOON.
ANOTHER MCS MAY DEVELOP AND MOVE THROUGH THE NORTHERN PART OF THE
FORECAST AREA AGAIN SATURDAY AS A SERIES OF WEAK WAVES MOVES THROUGH
THE RING OF FIRE ACROSS THE GREAT LAKES. BUT LOW CONFIDENCE THIS FAR
OUT. THE GENERAL TREND OF THE MODELS IS TO SLOWLY BUILD THE RIDGE
INTO THE WESTERN GREAT LAKES OVER THE WEEKEND. THEREFORE HAVE JUST
LOW CHANCE POPS FOR SATURDAY AND A DRY FORECAST FOR SUNDAY. MONDAY
THROUGH WEDNESDAY A SERIES OF WAVES SUPPRESSES THE RIDGE...WHICH
EVENTUALLY RE-ESTABLISHES ITSELF OVER THE WESTERN US. BY THE END
OF THE WEEK MODELS IN DECENT AGREEMENT IN DEVELOPING AN UPPER LOW
OVER THE GREAT LAKES.
MAX TEMPERATURES EXPECTED TO BE IN THE UPPER 80S TO AROUND 90 TODAY
THROUGH WEDNESDAY...WITH DEW POINTS IN THE UPPER 60S TO AROUND 70.
THIS PRODUCES HEAT INDEX VALUES IN MID TO UPPER 90S. THIS IS
BELOW LOCAL HEAT ADVISORY THRESHOLDS. HOWEVER SEEING AS THIS IS
THE FIRST HEAT WAVE OF THE SUMMER AND IT MAY PERSIST FOR SEVERAL
DAYS. A HEAT ADVISORY MAY NEED TO BE CONSIDERED BY EARLY TO MID
WEEK. ANY THUNDERSTORMS AND ASSOCIATED CLOUD COVER/OUTFLOW
BOUNDARIES MAY TEMPORARILY COOL THINGS DOWN AND IMPACT ANY FUTURE
DECISIONS ON HEAT HEADLINES.
PATTERN LOOKS TO BECOME MUCH COOLER NEXT WEEKEND.
ALLSOPP
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* SOUTHERLY WINDS LESS THAN 10KT THRU DAYBREAK...FREQUENT GUSTS
BETWEEN 15-20KT LATE MORNING THRU EARLY EVENING.
* PSBL THUNDERSTORMS AFT 20Z THRU EARLY EVENING.
BEACHLER
//DISCUSSION...UPDATED 06Z...
REGIONAL RADAR SHOWS A BROKEN LINE OF SHOWERS AND THUNDERSTORMS
JUST WEST OF THE MISSISSIPPI RIVER IN EASTERN IOWA. THIS AREA OF
PRECIPITATION WAS SLIDING EAST...HOWEVER ALL GUIDANCE IS POINTING
TOWARDS THIS LINE WEAKENING OVER THE NEXT SEVERAL HOURS AND NOT
REACHING THE TAF SITES. FEEL RELATIVELY CONFIDENT IN THIS
SCENARIO...AND HAVE CONTINUED TO KEEP THE TAF SITES DRY THRU
DAYBREAK. A WEAK LOW PRESSURE CENTERED ACROSS THE CENTRAL
PLAINS...WILL MAINTAIN A SOUTHERLY FLOW FOR NORTHERN IL/NORTHWEST
IN AIRFIELDS TODAY. A WEAK INCREASE IN THE GRADIENT DOES APPEAR
LIKELY LATE MORNING THROUGH THE AFTERN/EARLY EVENING HOURS...WHICH
SHOULD RESULT IN FREQUENT GUSTS BETWEEN 15-20KT. AFT SUNSET
TOWARDS 02-03Z SAT...WINDS WILL DIMINISH TO ARND 10KT FROM THE
SOUTH.
THE OTHER CONCERN IS FOR A COMPLEX OF THUNDERSTORMS CURRENTLY OVER
THE UPPER MIDWEST...AND POSSIBLY CLIPPING NORTHERN IL/NORTHWEST IN
AIRFIELDS LATER THIS AFTN. WITH INCREASING MID-LVL HIGH
PRESSURE...THIS SHOULD KEEP THE BULK OF THE PRECIP TO THE NORTH.
ALTHOUGH THIS BEING SAID GUIDANCE DOES INDICATE SOME THUNDERSTORMS
BRUSHING THE TAF SITES. HAVE OPTED TO MAINTAIN THE MENTION WITHIN
A PROB30 GROUP.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* HIGH CONFIDENCE IN WIND DIR/SPEED/GUSTS.
* HIGH CONFIDENCE IN CIGS FORECAST THRU EARLY AFTN.
* MEDIUM CONFIDENCE IN PRECIP DEVELOPMENT AND COVERAGE.
* LOW CONFIDENCE IN THUNDERSTORMS IMPACTING TAF SITES.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 12Z SATURDAY-12Z THURSDAY...UPDATED 00Z...
SATURDAY...CHANCE TS. ELSE VFR.
SUNDAY...VFR.
MONDAY THROUGH WEDNESDAY...PERIODIC CHANCES FOR TS. ELSE VFR.
ZEBIC
&&
.MARINE...
240 AM CDT
MAIN CONCERN FOR LAKE MICHIGAN WILL BE POTENTIAL FOR FOG
DEVELOPMENT AND TIMING...ALONG WITH CHANCES FOR THUNDERSTORMS. AT
THIS TIME THERE DOES NOT APPEAR TO BE ANY WIND/WAVE HAZARDS
EXPECTED IN THE NEXT SEVERAL DAYS.
HIGH PRESURE ANCHORED ACROSS THE WESTERN ATLANTIC OCEAN ALONG WITH
A BROAD LOW PRESSURE ANCHORED OVER THE CENTRAL PLAINS...WILL
MAINTAIN THE SOUTHERLY FLOW OVER THE LAKE. IN ADDITION VERY WARM
AIR WILL SLIDE OVER THE COOLER OPEN WATERS OF THE LAKE...AND HELP
TO KEEP WAVES FROM BUILDING TO LARGE. THE GRADIENT THIS AFTERNOON
DOES INCREASE WHICH MAY ALLOW WINDS TO INCREASE TO AROUND 20-25KT
FOR THE NORTHERN HALF OF THE LAKE...HOWEVER WAVES SHOULD ONLY
BUILD TO 2 TO 4 FT. AT TIMES WINDS MAY GUST TO 25 KT FURTHER SOUTH
THIS AFTERNOON. THUNDERSTORMS ARE FORECAST FOR THE NEXT SEVERAL
DAYS...HOWEVER THESE DO NOT APPEAR TO BE AN ALL DAY OR NIGHT
THING. BUT WINDS/WAVES WILL BE HIGHER IN AND AROUND ANY
THUNDERSTORMS THAT DO SLIDE ACROSS THE LAKE.
AS MENTIONED EARLIER ABOUT THE FOG DEVELOPMENT. IT DOES APPEAR
THAT WITH ENOUGH WIND THIS AFTERNOON FOG WILL HOLD OFF UNTIL
PERHAPS LATE TONIGHT OR POSSIBLY SATURDAY. A WARM FRONT WILL LIFT
NORTH OVER THE LAKE...WITH FOG DEVELOPMENT EXPECTED JUST AFTER
PASSAGE. THIS STILL APPEARS TO FAVOR THE NORTHERN PORTIONS OF THE
LAKE AND AT TIMES COULD BE DENSE. ONCE FOG DEVELOPS IT COULD
EASILY LINGER THROUGH EARLY NEXT WEEK AS THE WINDS ARE NOT
EXPECTED TO BE VERY STRONG.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
338 AM CDT FRI JUN 21 2013
.DISCUSSION...
329 AM CDT
THE MAIN FORECAST CHALLENGE FOR THE SHORT TERM WILL BE THE EVOLUTION
OF THE MCS OVER THE UPPER MS VALLEY TODAY. THIS COULD BE FOLLOWED
BY ADDITIONAL STORM CLUSTERS THROUGH SATURDAY...AND AGAIN MONDAY
THROUGH WEDNESDAY. ALSO THE BUILDING HEAT AND HUMIDITY THROUGH
THE MIDDLE OF NEXT WEEK.
IN THE SHORT TERM A NARROW BAND OF SHOWERS AND WEAK THUNDERSTORMS
EXTENDS FROM WESTERN WI TO THE IL/IA BORDER. THIS ACTIVITY OCCURRING
ALONG AN AXIS OF HIGHER LOW LEVEL MOISTURE AND THE EASTERN EDGE OF
THE LOW LEVEL JET. EXPECT THIS ACTIVITY TO WEAKEN AND DIE EARLY THIS
MORNING AS IT MOVES INTO DRIER AND MORE STABLE ATMOSPHERE. HAVE SOME
LOW POPS FOR FAR WESTERN COUNTIES THROUGH MID MORNING. MEANWHILE
VERY ACTIVE MCS OVER MN DIVING SOUTHEAST. THIS ACTIVITY SHOULD BE
ON A DIURNALLY WEAKENING TREND LATER THIS MORNING. MEAN MID AND
UPPER LEVEL WINDS ARE WESTERLY WITH FLAT RIDGE ACROSS THE UPPER MS
VALLEY AND GREAT LAKES...WHICH MIGHT SUGGEST THIS WILL REMAIN
MAINLY NORTH OVER WISCONSIN...BUT ACTIVITY IS DROPPING SOUTHEAST
AS CONVECTION BACK BUILDS INTO LOW LEVEL JET. IF IT HOLDS
TOGETHER ON ITS PRESENT COURSE...IT WILL BE APPROACHING NORTHWEST
AND NORTH CENTRAL IL BY LATE MORNING. HRRR SEEMS TO BE THE MOST
AGGRESSIVE OF THE SHORT TERM GUIDANCE IN BRINGING PRECIP INTO
NORTHERN IL TODAY. DEEP LAYER SHEAR WILL BE LACKING THIS FAR
SOUTH BUT WITH BUILDING HEAT AND SURFACE DEW POINTS CLIMBING INTO
THE MID AND UPPER 60S...THERE MAY BE SUFFICIENT LOW LEVEL
INSTABILITY FOR STORMS TO CONTINUE SOUTHEASTWARD INTO IL. HAVE
MAINTAINED 30-40 PERCENT POPS MAINLY FOR NORTHERN COUPLE OF TIERS
OF COUNTIES. SPC HAS MUCH OF NORTHERN IL IN SLIGHT RISK FOR WIND
AND HAIL THREAT. THE ASSOCIATED CIRRUS SHIELD MAY ALSO IMPACT
TEMPERATURES. THEREFORE HAVE LOWERED MAX TEMPS ACROSS THE FAR NORTH
DOWN A COUPLE DEGREES TO THE MID 80S WHILE KEEPING MAX TEMPS IN
UPPER 80S TO NEAR 90 FURTHER SOUTH. EXPECT SOUTH WINDS TO BE
SUFFICIENTLY STRONG TO PREVENT A LAKE BREEZE. ALTHOUGH WITH SOUTH
TO SLIGHTLY EAST OF SOUTH WINDS...A WEAK LAKE BREEZE MAY DRIFT
ONSHORE ACROSS NORTHERN COOK AND LAKE COUNTY IN THIS AFTERNOON.
ANOTHER MCS MAY DEVELOP AND MOVE THROUGH THE NORTHERN PART OF THE
FORECAST AREA AGAIN SATURDAY AS A SERIES OF WEAK WAVES MOVES THROUGH
THE RING OF FIRE ACROSS THE GREAT LAKES. BUT LOW CONFIDENCE THIS FAR
OUT. THE GENERAL TREND OF THE MODELS IS TO SLOWLY BUILD THE RIDGE
INTO THE WESTERN GREAT LAKES OVER THE WEEKEND. THEREFORE HAVE JUST
LOW CHANCE POPS FOR SATURDAY AND A DRY FORECAST FOR SUNDAY. MONDAY
THROUGH WEDNESDAY A SERIES OF WAVES SUPPRESSES THE RIDGE...WHICH
EVENTUALLY RE-ESTABLISHES ITSELF OVER THE WESTERN US. BY THE END
OF THE WEEK MODELS IN DECENT AGREEMENT IN DEVELOPING AN UPPER LOW
OVER THE GREAT LAKES.
MAX TEMPERATURES EXPECTED TO BE IN THE UPPER 80S TO AROUND 90 TODAY
THROUGH WEDNESDAY...WITH DEW POINTS IN THE UPPER 60S TO AROUND 70.
THIS PRODUCES HEAT INDEX VALUES IN MID TO UPPER 90S. THIS IS
BELOW LOCAL HEAT ADVISORY THRESHOLDS. HOWEVER SEEING AS THIS IS
THE FIRST HEAT WAVE OF THE SUMMER AND IT MAY PERSIST FOR SEVERAL
DAYS. A HEAT ADVISORY MAY NEED TO BE CONSIDERED BY EARLY TO MID
WEEK. ANY THUNDERSTORMS AND ASSOCIATED CLOUD COVER/OUTFLOW
BOUNDARIES MAY TEMPORARILY COOL THINGS DOWN AND IMPACT ANY FUTURE
DECISIONS ON HEAT HEADLINES.
PATTERN LOOKS TO BECOME MUCH COOLER NEXT WEEKEND.
ALLSOPP
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* SOUTHERLY WINDS LESS THAN 10KT THRU DAYBREAK...FREQUENT GUSTS
BETWEEN 15-20KT LATE MORNING THRU EARLY EVENING.
* PSBL THUNDERSTORMS AFT 20Z THRU EARLY EVENING.
BEACHLER
//DISCUSSION...UPDATED 06Z...
REGIONAL RADAR SHOWS A BROKEN LINE OF SHOWERS AND THUNDERSTORMS
JUST WEST OF THE MISSISSIPPI RIVER IN EASTERN IOWA. THIS AREA OF
PRECIPITATION WAS SLIDING EAST...HOWEVER ALL GUIDANCE IS POINTING
TOWARDS THIS LINE WEAKENING OVER THE NEXT SEVERAL HOURS AND NOT
REACHING THE TAF SITES. FEEL RELATIVELY CONFIDENT IN THIS
SCENARIO...AND HAVE CONTINUED TO KEEP THE TAF SITES DRY THRU
DAYBREAK. A WEAK LOW PRESSURE CENTERED ACROSS THE CENTRAL
PLAINS...WILL MAINTAIN A SOUTHERLY FLOW FOR NORTHERN IL/NORTHWEST
IN AIRFIELDS TODAY. A WEAK INCREASE IN THE GRADIENT DOES APPEAR
LIKELY LATE MORNING THROUGH THE AFTERN/EARLY EVENING HOURS...WHICH
SHOULD RESULT IN FREQUENT GUSTS BETWEEN 15-20KT. AFT SUNSET
TOWARDS 02-03Z SAT...WINDS WILL DIMINISH TO ARND 10KT FROM THE
SOUTH.
THE OTHER CONCERN IS FOR A COMPLEX OF THUNDERSTORMS CURRENTLY OVER
THE UPPER MIDWEST...AND POSSIBLY CLIPPING NORTHERN IL/NORTHWEST IN
AIRFIELDS LATER THIS AFTN. WITH INCREASING MID-LVL HIGH
PRESSURE...THIS SHOULD KEEP THE BULK OF THE PRECIP TO THE NORTH.
ALTHOUGH THIS BEING SAID GUIDANCE DOES INDICATE SOME THUNDERSTORMS
BRUSHING THE TAF SITES. HAVE OPTED TO MAINTAIN THE MENTION WITHIN
A PROB30 GROUP.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE IN WIND DIR/SPEED/GUSTS.
* HIGH CONFIDENCE IN CIGS FORECAST THRU EARLY AFTN.
* MEDIUM CONFIDENCE IN PRECIP DEVELOPMENT AND COVERAGE.
* LOW CONFIDENCE IN THUNDERSTORMS IMPACTING TAF SITES.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 12Z SATURDAY-12Z THURSDAY...UPDATED 00Z...
SATURDAY...CHANCE TS. ELSE VFR.
SUNDAY...VFR.
MONDAY THROUGH WEDNESDAY...PERIODIC CHANCES FOR TS. ELSE VFR.
ZEBIC
&&
.MARINE...
240 AM CDT
MAIN CONCERN FOR LAKE MICHIGAN WILL BE POTENTIAL FOR FOG
DEVELOPMENT AND TIMING...ALONG WITH CHANCES FOR THUNDERSTORMS. AT
THIS TIME THERE DOES NOT APPEAR TO BE ANY WIND/WAVE HAZARDS
EXPECTED IN THE NEXT SEVERAL DAYS.
HIGH PRESURE ANCHORED ACROSS THE WESTERN ATLANTIC OCEAN ALONG WITH
A BROAD LOW PRESSURE ANCHORED OVER THE CENTRAL PLAINS...WILL
MAINTAIN THE SOUTHERLY FLOW OVER THE LAKE. IN ADDITION VERY WARM
AIR WILL SLIDE OVER THE COOLER OPEN WATERS OF THE LAKE...AND HELP
TO KEEP WAVES FROM BUILDING TO LARGE. THE GRADIENT THIS AFTERNOON
DOES INCREASE WHICH MAY ALLOW WINDS TO INCREASE TO AROUND 20-25KT
FOR THE NORTHERN HALF OF THE LAKE...HOWEVER WAVES SHOULD ONLY
BUILD TO 2 TO 4 FT. AT TIMES WINDS MAY GUST TO 25 KT FURTHER SOUTH
THIS AFTERNOON. THUNDERSTORMS ARE FORECAST FOR THE NEXT SEVERAL
DAYS...HOWEVER THESE DO NOT APPEAR TO BE AN ALL DAY OR NIGHT
THING. BUT WINDS/WAVES WILL BE HIGHER IN AND AROUND ANY
THUNDERSTORMS THAT DO SLIDE ACROSS THE LAKE.
AS MENTIONED EARLIER ABOUT THE FOG DEVELOPMENT. IT DOES APPEAR
THAT WITH ENOUGH WIND THIS AFTERNOON FOG WILL HOLD OFF UNTIL
PERHAPS LATE TONIGHT OR POSSIBLY SATURDAY. A WARM FRONT WILL LIFT
NORTH OVER THE LAKE...WITH FOG DEVELOPMENT EXPECTED JUST AFTER
PASSAGE. THIS STILL APPEARS TO FAVOR THE NORTHERN PORTIONS OF THE
LAKE AND AT TIMES COULD BE DENSE. ONCE FOG DEVELOPS IT COULD
EASILY LINGER THROUGH EARLY NEXT WEEK AS THE WINDS ARE NOT
EXPECTED TO BE VERY STRONG.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1232 PM CDT FRI JUN 21 2013
.SHORT TERM.../TODAY/...
ISSUED AT 331 AM CDT FRI JUN 21 2013
LARGE CONVECTIVE COMPLEX OVER MN BEGINNING TO TURN SOUTHEAST AND
BATTLING H700 CAP AT THIS TIME AS IT DOES. CONTINUED CONCERNS EARLY
THIS MORNING AS TO HOW FAR SOUTH THIS WILL TURN BEFORE THE CAP
BECOMES TOO STRONG FOR ANY FURTHER SOUTH DRIFT. COLD POOL HAS
DEVELOPED WITH SFC WINDS AND OUTFLOW PROPAGATING BACK TO THE
SOUTHWEST. THIS SUGGESTS THAT IT MAY CLIP NORTHERN IOWA WITH STORMS
THIS MORNING BETWEEN 4 AND 8 AM...IF THE LINE IS ABLE TO CONTINUE
BREAKING THE CAP BACK TO THE SOUTHWEST...MAY SEE ADDITIONAL STORMS
INTO CENTRAL IOWA. CURRENT MESO MODELS ARE LACKING IN ANY AGREEMENT
BUT THE HRRR HAS BEEN MORE REALISTIC WITH FEATURES SO FAR AND IT
ONLY SCRAPES NORTHERN IOWA EARLY TODAY WITH THIS COMPLEX OF STORMS.
ONCE SYSTEM MOVES EAST WILL BE LEFT WITH ANOTHER VERY WARM AND HUMID
DAY. THIS WILL RESULT IN HIGHS IN THE UPPER 80S TO LOWER 90S THIS
AFTERNOON WITH SOUTH WINDS AND GENEROUS DEW POINTS IN THE 60S AND
LOWER 70S. MORE CONVECTION MAY DEVELOP THIS AFTERNOON NORTH OF
HIGHWAY 20 ALONG ANY LINGERING OUTFLOW BOUNDARY FROM THE OVERNIGHT
CONVECTIVE COMPLEX AND THIS IS MORE LIKELY AFT 19Z THROUGH THE
REMAINDER OF THE AFTERNOON. WILL BE MONITORING CONVECTIVE TRENDS
THROUGH THE MORNING HOURS.
.LONG TERM.../TONIGHT THROUGH THURSDAY/...
ISSUED AT 331 AM CDT FRI JUN 21 2013
EXTENDED FORECAST CONTINUES TO CENTER AROUND LARGE UPPER LEVEL LOW
ACROSS PAC NW...AND SURFACE LOW ACROSS NORTHERN PLAINS WITH WARM
FRONT IN SOUTHERN SD/MN. THIS WILL CONTINUE TO BE THE FOCUS FOR
AFTERNOON CONVECTION...AND MODELS AGAIN SUGGEST MCS DEVELOPMENT
OVERNIGHT. HOWEVER..AS UPPER LOW PUSHES EASTWARD...RIDGE PUSHES
NORTH OF IOWA...AND UPPER LEVEL FLOW IS EXPECTED TO TAKE ANY
OVERNIGHT MCS NORTH OF IOWA. THOUGH...CURRENTLY ONGOING MCS ACROSS
SOUTHERN MINNESOTA MAY PRODUCE AN OUTFLOW BOUNDARY INTO NORTHERN
IOWA...WHICH MAY ALLOW FOR TRACK OF MCS TO BE FURTHER SOUTH INTO
NORTHERN IOWA. THOUGH GIVEN STRENGTH OF UPPER LEVEL LOW...STILL
PREFER NORTHERN SOLUTION...AND HAVE KEPT POPS CONFINED TO
NORTHERN IOWA OVERNIGHT.
SATURDAY NIGHT LOOKS TO BE ACTIVE AS WELL...WITH FRONTAL BOUNDARY
PUSHING INTO NORTHWESTERN IOWA. THIS COULD BE FOCUS FOR AFTERNOON
THUNDERSTORM DEVELOPMENT...WITH AGAIN OVERNIGHT MCS...THOUGH WITH
INFLUENCE FROM UPPER LOW MODELS CONTINUE TO PULL CONVECTION
NORTHWEST OF IOWA...AND HAVE KEPT POPS AGAIN CONFINED TO THE
NORTH...AS WARM MID LEVEL TEMPS WILL HELP TO KEEP CAP ACROSS MOST
OF CENTRAL IOWA. SUNDAY FRONTAL BOUNDARY WILL PUSH INTO CENTRAL
IOWA...WITH ENOUGH FORCING TO LEAD TO PROLONGED PERIODS OF
PRECIPITATION THROUGH THE DAY AND OVERNIGHT...THOUGH WILL PUSH EAST
OF REGION BY MONDAY. SHORTWAVE PUSHING ACROSS NE/SD BORDER WILL
BRING ADDITIONAL SHOT OF PRECIPITATION FOR TUESDAY...LINGERING IN
THE EAST THROUGH WEDNESDAY.
TEMPERATURES WILL BE HOT THROUGH THE BEGINNING OF THE PERIOD AS
SOUTHERLY SURFACE FLOW AND WAA PERSISTS UNDER RIDGE. THIS WILL
ALLOW TEMPERATURES TO CLIMB INTO THE 90S ACROSS MUCH OF THE
CWA...THOUGH COULD GO HIGHER THAN GOING IF ABLE TO MIX WELL. HEAT
INDEX VALUES WILL BE NEAR 100 THROUGH THE WEEKEND IN THE
AFTERNOONS. THIS WILL BE THE FIRST EXPOSURE SUMMER LIKE
HEAT/HUMIDITY FOR MUCH OF THE REGION...AND MAY BE TAXING.
HOWEVER...OVERNIGHT TEMPERATURES EXPECTED TO COOL INTO THE 70S AND
WILL PROVIDE SOME RELIEF. IN ADDITION...BEHIND FRONTAL BOUNDARY
MONDAY TEMPERATURES WILL COOL SOMEWHAT...BUT WILL QUICKLY REBOUND
BACK INTO THE UPPER 80S AND LOW 80S FOR MOST OF THE REMAINDER OF
THE PERIOD.
&&
.AVIATION...21/18Z
ISSUED AT 1232 PM CDT FRI JUN 21 2013
PROBLEMATIC CONVECTIVE FORECAST COMPLICATES THE TAFS THROUGH
TONIGHT. CURRENTLY WDLY SCT SHRA/TSRA ARE AFFECTING OR APPROACHING
KFOD/KDSM/KOTM...BUT THEY ARE SMALL AND OF MINIMAL/BRIEF IMPACT SO
HAVE ADVERTISED ONLY WITH VCTS THIS AFTN AT THOSE TERMINALS.
MEANWHILE A LARGE CLUSTER OF TSRA ACROSS CTL SDAK IS APPROACHING
AND MAY IMPACT THE NORTHERN TERMINALS OVERNIGHT. THESE STORMS
COULD HAVE A MORE SUBSTANTIAL IMPACT...HOWEVER UNCERTAINTY IN
CONVECTIVE EVOLUTION IS HIGH AND THEY MAY NOT REACH THE AREA AT
ALL. THUS HAVE ALSO GONE WITH VCTS FOR THAT SCENARIO. BR IS ALSO
EXPECTED LATE TONIGHT...ESPECIALLY ACROSS THE NORTH...BUT DUE TO
UNPREDICTABILITY OF OTHER VARIABLES HAVE ONLY INCLUDED 6SM AT THIS
TIME. EXPECT FREQUENT TAF UPDATES LATER TODAY AND TONIGHT.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...REV
LONG TERM...AWB
AVIATION...LEE
AREA FORECAST DISCUSSION
NWS DES MOINES IA
617 AM CDT FRI JUN 21 2013
.SHORT TERM.../TODAY/...
ISSUED AT 331 AM CDT FRI JUN 21 2013
LARGE CONVECTIVE COMPLEX OVER MN BEGINNING TO TURN SOUTHEAST AND
BATTLING H700 CAP AT THIS TIME AS IT DOES. CONTINUED CONCERNS EARLY
THIS MORNING AS TO HOW FAR SOUTH THIS WILL TURN BEFORE THE CAP
BECOMES TOO STRONG FOR ANY FURTHER SOUTH DRIFT. COLD POOL HAS
DEVELOPED WITH SFC WINDS AND OUTFLOW PROPAGATING BACK TO THE
SOUTHWEST. THIS SUGGESTS THAT IT MAY CLIP NORTHERN IOWA WITH STORMS
THIS MORNING BETWEEN 4 AND 8 AM...IF THE LINE IS ABLE TO CONTINUE
BREAKING THE CAP BACK TO THE SOUTHWEST...MAY SEE ADDITIONAL STORMS
INTO CENTRAL IOWA. CURRENT MESO MODELS ARE LACKING IN ANY AGREEMENT
BUT THE HRRR HAS BEEN MORE REALISTIC WITH FEATURES SO FAR AND IT
ONLY SCRAPES NORTHERN IOWA EARLY TODAY WITH THIS COMPLEX OF STORMS.
ONCE SYSTEM MOVES EAST WILL BE LEFT WITH ANOTHER VERY WARM AND HUMID
DAY. THIS WILL RESULT IN HIGHS IN THE UPPER 80S TO LOWER 90S THIS
AFTERNOON WITH SOUTH WINDS AND GENEROUS DEW POINTS IN THE 60S AND
LOWER 70S. MORE CONVECTION MAY DEVELOP THIS AFTERNOON NORTH OF
HIGHWAY 20 ALONG ANY LINGERING OUTFLOW BOUNDARY FROM THE OVERNIGHT
CONVECTIVE COMPLEX AND THIS IS MORE LIKELY AFT 19Z THROUGH THE
REMAINDER OF THE AFTERNOON. WILL BE MONITORING CONVECTIVE TRENDS
THROUGH THE MORNING HOURS.
.LONG TERM.../TONIGHT THROUGH THURSDAY/...
ISSUED AT 331 AM CDT FRI JUN 21 2013
EXTENDED FORECAST CONTINUES TO CENTER AROUND LARGE UPPER LEVEL LOW
ACROSS PAC NW...AND SURFACE LOW ACROSS NORTHERN PLAINS WITH WARM
FRONT IN SOUTHERN SD/MN. THIS WILL CONTINUE TO BE THE FOCUS FOR
AFTERNOON CONVECTION...AND MODELS AGAIN SUGGEST MCS DEVELOPMENT
OVERNIGHT. HOWEVER..AS UPPER LOW PUSHES EASTWARD...RIDGE PUSHES
NORTH OF IOWA...AND UPPER LEVEL FLOW IS EXPECTED TO TAKE ANY
OVERNIGHT MCS NORTH OF IOWA. THOUGH...CURRENTLY ONGOING MCS ACROSS
SOUTHERN MINNESOTA MAY PRODUCE AN OUTFLOW BOUNDARY INTO NORTHERN
IOWA...WHICH MAY ALLOW FOR TRACK OF MCS TO BE FURTHER SOUTH INTO
NORTHERN IOWA. THOUGH GIVEN STRENGTH OF UPPER LEVEL LOW...STILL
PREFER NORTHERN SOLUTION...AND HAVE KEPT POPS CONFINED TO
NORTHERN IOWA OVERNIGHT.
SATURDAY NIGHT LOOKS TO BE ACTIVE AS WELL...WITH FRONTAL BOUNDARY
PUSHING INTO NORTHWESTERN IOWA. THIS COULD BE FOCUS FOR AFTERNOON
THUNDERSTORM DEVELOPMENT...WITH AGAIN OVERNIGHT MCS...THOUGH WITH
INFLUENCE FROM UPPER LOW MODELS CONTINUE TO PULL CONVECTION
NORTHWEST OF IOWA...AND HAVE KEPT POPS AGAIN CONFINED TO THE
NORTH...AS WARM MID LEVEL TEMPS WILL HELP TO KEEP CAP ACROSS MOST
OF CENTRAL IOWA. SUNDAY FRONTAL BOUNDARY WILL PUSH INTO CENTRAL
IOWA...WITH ENOUGH FORCING TO LEAD TO PROLONGED PERIODS OF
PRECIPITATION THROUGH THE DAY AND OVERNIGHT...THOUGH WILL PUSH EAST
OF REGION BY MONDAY. SHORTWAVE PUSHING ACROSS NE/SD BORDER WILL
BRING ADDITIONAL SHOT OF PRECIPITATION FOR TUESDAY...LINGERING IN
THE EAST THROUGH WEDNESDAY.
TEMPERATURES WILL BE HOT THROUGH THE BEGINNING OF THE PERIOD AS
SOUTHERLY SURFACE FLOW AND WAA PERSISTS UNDER RIDGE. THIS WILL
ALLOW TEMPERATURES TO CLIMB INTO THE 90S ACROSS MUCH OF THE
CWA...THOUGH COULD GO HIGHER THAN GOING IF ABLE TO MIX WELL. HEAT
INDEX VALUES WILL BE NEAR 100 THROUGH THE WEEKEND IN THE
AFTERNOONS. THIS WILL BE THE FIRST EXPOSURE SUMMER LIKE
HEAT/HUMIDITY FOR MUCH OF THE REGION...AND MAY BE TAXING.
HOWEVER...OVERNIGHT TEMPERATURES EXPECTED TO COOL INTO THE 70S AND
WILL PROVIDE SOME RELIEF. IN ADDITION...BEHIND FRONTAL BOUNDARY
MONDAY TEMPERATURES WILL COOL SOMEWHAT...BUT WILL QUICKLY REBOUND
BACK INTO THE UPPER 80S AND LOW 80S FOR MOST OF THE REMAINDER OF
THE PERIOD.
&&
.AVIATION...21/12Z
ISSUED AT 617 AM CDT FRI JUN 21 2013
MAIN CONCERN WILL BE CONVECTION EARLY TODAY AND AGAIN THIS AFTERNOON
AND NIGHT. AMBIENT WINDS WILL ALSO POSE SOME ISSUES AS GRADIENT
REMAINS STRONG WITH SOUTH WINDS THROUGH THE DAY MIXING TO ABOUT 20
TO 25 KTS ACROSS THE REGION. OLD MCC IN MINNESOTA EARLY TODAY
CONTINUES TO PUSH EAST WITH OUTFLOW BOUNDARY CONVECTION NOW ENTERING
NORTHERN IOWA. THIS WILL MAINLY AFFECT KMCW EARLY TODAY AND POSSIBLY
KALO TO A LESSER EXTENT. WINDS MAY PICK UP AS BOUNDARY INTERACTS
WITH MORE UNSTABLE AIR THROUGH ABOUT 16Z AND WILL MONITOR FOR STRONG
WIND GUST POTENTIAL AT KMCW AND KALO. ONCE CONVECTION PUSHES EAST...
GRADIENT WINDS WILL INCREASE FROM THE SOUTH AFT 16Z. OLD OUTFLOW
BOUNDARY MAY BE FOCUS FOR AFTERNOON CONVECTION NORTH SITES ONCE
AGAIN BUT STRONG CAP AT H700 WILL INHIBIT ANY CONVECTION FOR KFOD
KDSM...AND KOTM THROUGH REMAINDER OF PERIOD. AS NIGHTFALL APPROACHES
ANOTHER ROUND OF CONVECTION MAY DEVELOP NORTH OF STATE AND AGAIN
AFFECT NORTHERN SITES BETWEEN 04 AND 09Z ON THE 22ND.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...REV
LONG TERM...AWB
AVIATION...REV
AREA FORECAST DISCUSSION
NWS DES MOINES IA
335 AM CDT FRI JUN 21 2013
.SHORT TERM.../TODAY/...
ISSUED AT 331 AM CDT FRI JUN 21 2013
LARGE CONVECTIVE COMPLEX OVER MN BEGINNING TO TURN SOUTHEAST AND
BATTLING H700 CAP AT THIS TIME AS IT DOES. CONTINUED CONCERNS EARLY
THIS MORNING AS TO HOW FAR SOUTH THIS WILL TURN BEFORE THE CAP
BECOMES TOO STRONG FOR ANY FURTHER SOUTH DRIFT. COLD POOL HAS
DEVELOPED WITH SFC WINDS AND OUTFLOW PROPAGATING BACK TO THE
SOUTHWEST. THIS SUGGESTS THAT IT MAY CLIP NORTHERN IOWA WITH STORMS
THIS MORNING BETWEEN 4 AND 8 AM...IF THE LINE IS ABLE TO CONTINUE
BREAKING THE CAP BACK TO THE SOUTHWEST...MAY SEE ADDITIONAL STORMS
INTO CENTRAL IOWA. CURRENT MESO MODELS ARE LACKING IN ANY AGREEMENT
BUT THE HRRR HAS BEEN MORE REALISTIC WITH FEATURES SO FAR AND IT
ONLY SCRAPES NORTHERN IOWA EARLY TODAY WITH THIS COMPLEX OF STORMS.
ONCE SYSTEM MOVES EAST WILL BE LEFT WITH ANOTHER VERY WARM AND HUMID
DAY. THIS WILL RESULT IN HIGHS IN THE UPPER 80S TO LOWER 90S THIS
AFTERNOON WITH SOUTH WINDS AND GENEROUS DEW POINTS IN THE 60S AND
LOWER 70S. MORE CONVECTION MAY DEVELOP THIS AFTERNOON NORTH OF
HIGHWAY 20 ALONG ANY LINGERING OUTFLOW BOUNDARY FROM THE OVERNIGHT
CONVECTIVE COMPLEX AND THIS IS MORE LIKELY AFT 19Z THROUGH THE
REMAINDER OF THE AFTERNOON. WILL BE MONITORING CONVECTIVE TRENDS
THROUGH THE MORNING HOURS.
.LONG TERM.../TONIGHT THROUGH THURSDAY/...
ISSUED AT 331 AM CDT FRI JUN 21 2013
EXTENDED FORECAST CONTINUES TO CENTER AROUND LARGE UPPER LEVEL LOW
ACROSS PAC NW...AND SURFACE LOW ACROSS NORTHERN PLAINS WITH WARM
FRONT IN SOUTHERN SD/MN. THIS WILL CONTINUE TO BE THE FOCUS FOR
AFTERNOON CONVECTION...AND MODELS AGAIN SUGGEST MCS DEVELOPMENT
OVERNIGHT. HOWEVER..AS UPPER LOW PUSHES EASTWARD...RIDGE PUSHES
NORTH OF IOWA...AND UPPER LEVEL FLOW IS EXPECTED TO TAKE ANY
OVERNIGHT MCS NORTH OF IOWA. THOUGH...CURRENTLY ONGOING MCS ACROSS
SOUTHERN MINNESOTA MAY PRODUCE AN OUTFLOW BOUNDARY INTO NORTHERN
IOWA...WHICH MAY ALLOW FOR TRACK OF MCS TO BE FURTHER SOUTH INTO
NORTHERN IOWA. THOUGH GIVEN STRENGTH OF UPPER LEVEL LOW...STILL
PREFER NORTHERN SOLUTION...AND HAVE KEPT POPS CONFINED TO
NORTHERN IOWA OVERNIGHT.
SATURDAY NIGHT LOOKS TO BE ACTIVE AS WELL...WITH FRONTAL BOUNDARY
PUSHING INTO NORTHWESTERN IOWA. THIS COULD BE FOCUS FOR AFTERNOON
THUNDERSTORM DEVELOPMENT...WITH AGAIN OVERNIGHT MCS...THOUGH WITH
INFLUENCE FROM UPPER LOW MODELS CONTINUE TO PULL CONVECTION
NORTHWEST OF IOWA...AND HAVE KEPT POPS AGAIN CONFINED TO THE
NORTH...AS WARM MID LEVEL TEMPS WILL HELP TO KEEP CAP ACROSS MOST
OF CENTRAL IOWA. SUNDAY FRONTAL BOUNDARY WILL PUSH INTO CENTRAL
IOWA...WITH ENOUGH FORCING TO LEAD TO PROLONGED PERIODS OF
PRECIPITATION THROUGH THE DAY AND OVERNIGHT...THOUGH WILL PUSH EAST
OF REGION BY MONDAY. SHORTWAVE PUSHING ACROSS NE/SD BORDER WILL
BRING ADDITIONAL SHOT OF PRECIPITATION FOR TUESDAY...LINGERING IN
THE EAST THROUGH WEDNESDAY.
TEMPERATURES WILL BE HOT THROUGH THE BEGINNING OF THE PERIOD AS
SOUTHERLY SURFACE FLOW AND WAA PERSISTS UNDER RIDGE. THIS WILL
ALLOW TEMPERATURES TO CLIMB INTO THE 90S ACROSS MUCH OF THE
CWA...THOUGH COULD GO HIGHER THAN GOING IF ABLE TO MIX WELL. HEAT
INDEX VALUES WILL BE NEAR 100 THROUGH THE WEEKEND IN THE
AFTERNOONS. THIS WILL BE THE FIRST EXPOSURE SUMMER LIKE
HEAT/HUMIDITY FOR MUCH OF THE REGION...AND MAY BE TAXING.
HOWEVER...OVERNIGHT TEMPERATURES EXPECTED TO COOL INTO THE 70S AND
WILL PROVIDE SOME RELIEF. IN ADDITION...BEHIND FRONTAL BOUNDARY
MONDAY TEMPERATURES WILL COOL SOMEWHAT...BUT WILL QUICKLY REBOUND
BACK INTO THE UPPER 80S AND LOW 80S FOR MOST OF THE REMAINDER OF
THE PERIOD.
&&
.AVIATION...21/06Z
ISSUED AT 1204 AM CDT FRI JUN 21 2013
PLENTY OF MID/HIGH CLOUDS OVER IA AT 06Z BUT CONDITIONS REMAIN
VFR...EVEN WITH SCT CONVECTION EAST OF DMX TAF SITES. CONFIDENCE
IN CONVECTIVE TRENDS HAS DIMINISHED CONSIDERABLY AS NEARLY ALL
MODELS HAVE OVERDONE PRECIP INTO IA THIS EVENING AND HI RES MODELS
DO NOT APPEAR TO BE HANDLING PROGRESSION OF MN PRECIP WELL. THUS
UNTIL TRENDS BECOME MORE CLEAR HAVE REMOVED ALL MENTION OF PRECIP.
YOU COULD MAKE AN ARGUMENT FOR SOME MENTION OVERNIGHT INTO FRI
AND HAVE CHOSEN DRY RATHER THAN PROLONGED LOW CONFIDENCE
INCLUSION. SOUNDINGS SUGGEST SOMEWHAT BRISK SLY WINDS DURING PEAK
HEATING...MUCH LIKE WHAT OCCURRED THU.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...REV
LONG TERM...AWB
AVIATION...SMALL
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1204 AM CDT FRI JUN 21 2013
.UPDATE...
ISSUED AT 1203 AM CDT FRI JUN 21 2013
NO SIGNIFICANT FORECAST CHANGES HAVE BEEN MADE BUT OVERALL
CONFIDENCE IN CONVECTIVE TRENDS HAS DIMINISHED AS MODELS SEEM TO
BE DOING A POOR JOB HANDLING REALITY AT THE MOMENT. MOST 00Z
OPERATIONAL MODELS HAVE BEEN OVERZEALOUS WITH THEIR CONVECTION
INTO IA THIS EVENING...AND THE MOST RECENT RUNS OF HI RES MODELS
WITH THE POSSIBLE EXCEPTION OF RECENT HRRR RUNS HAVE BEEN TOO
QUICK EVOLVING THE MN MCS INTO A MORE ORGANIZED LINE DROPPING
TOWARD IA. MN MCS IS STILL MULTICELLULAR AND AS OF YET SHOWING
LITTLE SIGNS OF CONGEALING SWD. MODEL SOUNDINGS CONTINUE TO
DEPICT GRADUALLY MOISTENING TOWARD 06Z...BUT IF WARM ADVECTION
DOES NOT TRIGGER CONVECTION BY 09Z GENESIS WINDOW MAY HAVE BEEN
MISSED AS THIS MOISTURE WINDOWS SEEMS SOMEWHAT TRANSIENT. 03Z HRRR
ONLY BARELY BRUSHES NERN SECTIONS WITH MN COMPLEX 09-12Z WITH
NOTHING FARTHER SOUTH UNTIL LATER FRI MORNING.
&&
.SHORT TERM.../TONIGHT/...
ISSUED AT 407 PM CDT THU JUN 20 2013
THOUGH CAPE VALUES HAVE RANGED FROM 1000 TO 3000...WITH WIDESPREAD
DEWPOINTS IN THE MID 60S...THE LACK OF A FORCING MECHANISM HAS
HELPED IN PREVENTING CONVECTION FROM DEVELOPING ACROSS IOWA THUS FAR
TODAY. THERE IS A DOUBLE BARRELED AREA OF LOW PRESSURE TO THE
WEST...WITH ONE LOW SET UP OVER NEBRASKA...AND THE OTHER LOW OVER
NORTHERN MINNESOTA. THE SOUTHERN...LARGER...AREA OF LOW PRESSURE IS
NOT GOING TO MOVE VERY MUCH OVERNIGHT.
THUNDERSTORMS ARE EXPECTED ACROSS PARTS OF IOWA TONIGHT...AND THEY
SHOULD COME IN TWO DIFFERENT WAVES. WAVE ONE WILL BE FOCUSED OVER
WESTERN IOWA TONIGHT. THERE IS A STRONG LOW LEVEL JET SET UP OVER
IOWA...ALIGNED FROM SW TO NE...WHICH IS EXPECTED TO REMAIN IN PLACE
AND STRENGTHEN TONIGHT...REINFORCING MOISTURE FLOW FROM THE GULF TO
IOWA. A SHORT WAVE IS SLATED RIDE ALONG THE LOW AND MEET UP WITH
THE ENHANCED LOW LEVEL JET TONIGHT AROUND 06Z...WHICH IS A TYPICAL
TIME FOR NOCTURNAL CONVECTION TO DEVELOP...WITH THE CONDITIONS FOR
OVERTURNING IN PLACE.
WAVE TWO WILL COME FROM THE NORTH VIA A MCS WHICH IS EXPECTED TO
DEVELOP IN THE DAKOTAS AND MOVE EAST ACROSS MINNESOTA DURING THE
OVERNIGHT. WHILE MOST OF THE THUNDERSTORMS WILL BE IN
MINNESOTA...STORMS WILL LIKELY MAKE IT INTO THE DMX CWA...ESPECIALLY
NORTH OF INTERSTATE 80...AS A BOUNDARY SHOULD BE IN PLACE TO FOCUS
THE CONVECTION FOR THE MCS. CAPE VALUES SHOULD REMAIN IN THE 1000 TO
3000 RANGE OVERNIGHT...THERE IS THETA-E ADVECTION EXPECTED ACROSS
IOWA...AND THERE IS UPPER LEVEL DIVERGENCE OVER IOWA...WHICH ALL
SHOULD HELP SUSTAIN THE CONVECTION ALONG THE BOUNDARY AS THE MCS
PASSES THROUGH NORTHERN IOWA.
WITH THE REINFORCED MOISTURE TO REMAIN IN PLACE...OVERNIGHT
TEMPERATURES SHOULD REMAIN WELL ABOVE NORMAL IN THE UPPER 60S TO
LOWER 70S.
.LONG TERM.../FRIDAY THROUGH THURSDAY/...
ISSUED AT 407 PM CDT THU JUN 20 2013
THE FORECAST IS GENERALLY PROGRESSING AS EXPECTED WITH THE
COMBINATION OF UPPER LOW OVER THE PACIFIC NORTHWEST AND A
SUBTROPICAL HIGH OVER THE SOUTH TO SOUTHEAST YIELDING AN
INCREASING SOUTHWEST FLOW INTO IOWA. STILL POTENTIAL FOR OVERNIGHT
CONVECTION TO LINGER ACROSS THE AREA THROUGH FRIDAY MORNING BEFORE
AN INCREASING ELEVATED MIXED LAYER SPREADS INTO THE STATE AND CAPS
MUCH OF THE AREA FOR THE REMAINDER OF THE DAY. TEMPERATURES AT 700
MB BY LATE FRIDAY WILL BE IN THE 12C-14C RANGE. AN APPROACHING
SHORT WAVE FRIDAY NIGHT WILL HELP COOL THE MID LEVELS A BIT FIRE A
FEW STORMS. THE PRIMARY FOCUS FOR THUNDERSTORMS ON FRIDAY
AFTERNOON IS EXPECTED TO BE TO THE NORTHWEST OVER SOUTH DAKOTA.
CERTAINLY POSSIBLE SOME OF THIS ACTIVITY SPILLS OVER INTO NORTH
CENTRAL IOWA FRIDAY EVENING BEFORE THE CAP REESTABLISHES ON
SATURDAY. ANY STORMS WOULD HAVE SEVERE POTENTIAL AND A LOCALLY
HEAVY RAIN POTENTIAL WITH GOOD INSTABILITY...SUFFICIENT SHEAR AND
PWATS NEARING 1.75 INCHES.
ON SATURDAY THE STRONG ELEVATED MIXED LAYER REESTABLISHES WITH
CONVECTIVE INHIBITIONS EXPECTED TO HOLD FOR EVERYWHERE EXCEPT
POTENTIALLY NEARING THE MINNESOTA BORDER. A SERIES OF STRONG SHORT
WAVES PASS THROUGH THE REGION SATURDAY NIGHT THROUGH SUNDAY NIGHT
AND WILL KEEP CONVECTIVE CHANCES GOING THROUGH THE PERIOD MAINLY
CONFINED TO THE NORTH AND NORTHWEST BEFORE BEING MORE WIDESPREAD
SUNDAY NIGHT. THE REMAINDER OF THE EXTENDED WILL FEATURE STRONG
RIDGING BUILDING INTO THE INTER MOUNTAIN WEST EARLY TO MID NEXT
WEEK WITH MID 20C 850 MB TEMPERATURES ENTRENCHED ACROSS IOWA. THIS
WILL BE A DRIER PERIOD OVERALL BEFORE AN UPPER LOW DROPS INTO THE
NORTHERN PLAINS LATE WEDNESDAY INTO THURSDAY.
TEMPERATURES THROUGH THE FORECAST WILL BE SUMMER LIKE WITH WARMER
AND MORE HUMID CONDITIONS ARRIVING BY FRIDAY. HIGHS IN THE UPPER
80S TO MID 90S WITH DEWPOINTS IN THE UPPER 60S TO MID 70S WILL BE
COMMON THROUGHOUT LEADING HEAT INDEX VALUES EXCEEDING 100 AT TIMES.
&&
.AVIATION...21/06Z
ISSUED AT 1204 AM CDT FRI JUN 21 2013
PLENTY OF MID/HIGH CLOUDS OVER IA AT 06Z BUT CONDITIONS REMAIN
VFR...EVEN WITH SCT CONVECTION EAST OF DMX TAF SITES. CONFIDENCE
IN CONVECTIVE TRENDS HAS DIMINISHED CONSIDERABLY AS NEARLY ALL
MODELS HAVE OVERDONE PRECIP INTO IA THIS EVENING AND HI RES MODELS
DO NOT APPEAR TO BE HANDLING PROGRESSION OF MN PRECIP WELL. THUS
UNTIL TRENDS BECOME MORE CLEAR HAVE REMOVED ALL MENTION OF PRECIP.
YOU COULD MAKE AN ARGUMENT FOR SOME MENTION OVERNIGHT INTO FRI
AND HAVE CHOSEN DRY RATHER THAN PROLONGED LOW CONFIDENCE
INCLUSION. SOUNDINGS SUGGEST SOMEWHAT BRISK SLY WINDS DURING PEAK
HEATING...MUCH LIKE WHAT OCCURRED THU.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
UPDATE...SMALL
SHORT TERM...KOTENBERG
LONG TERM...DONAVON
AVIATION...SMALL
AREA FORECAST DISCUSSION
NWS WICHITA KS
652 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 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 651 PM CDT SAT JUN 22 2013
VFR CONDITIONS ARE EXPECTED ACROSS THE REGION FOR THE NEXT 24
HOURS. THE MAIN CONCERN WILL BE CONTINUED GUSTY SOUTH-SOUTHWEST
WINDS AS THE LEE SIDE TROUGH REMAINS STATIONARY OVER WRN KS. WILL
SEE THE STRONGEST WINDS DURING THE DAYTIME HOURS...BUT STILL COULD
SEE SOME GUSTS TO 20-25 KTS OVERNIGHT.
CONVECTION OVER NW KS COULD POSSIBLY TREK EAST-NORTHEAST LATE
TONIGHT...BUT WILL STAY MAINLY JUST TO THE NW OF KRSL. COULD SEE AN
OUTFLOW BOUNDARY FROM THIS CONVECTION DROP SOUTHEAST...WHICH COULD
LEAD TO AN ISOLATED SHOWER CHANCE NEAR KRSL FROM 09-12Z/SUN. BUT
GIVEN THE REMOTE CHANCE FOR THIS TO OCCUR...WILL NOT ADD ANY MENTION
INTO THE KRSL TAF JUST YET.
KETCHAM
&&
.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...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
217 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 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1115 AM MDT FRI JUN 21 2013
VFR CONDITIONS ARE FORECAST FOR THE NEXT 24 HOURS AT KMCK AND
KGLD. IT IS POSSIBLE THAT ISOLATED...HIGH-BASED THUNDERSTORMS
DEVELOP THIS AFTERNOON ALONG A DRYLINE AND MOVE TO THE EAST.
COVERAGE SHOULD BE FAIRLY SPARSE SO DID NOT MENTION ANY THUNDER IN
THE TAFS. GUSTY SOUTH WINDS WILL BEGIN THIS AFTERNOON AND CONTINUE
WELL INTO THE NIGHT. WINDS AT KGLD WILL VEER TO THE NORTHWEST
TOMORROW MORNING AS A WEAK FRONT MOVES IN WHILE WINDS AT KMCK
SHOULD REMAIN FROM THE SOUTH.
&&
.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...RRH
FIRE WEATHER...RRH
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1207 AM CDT FRI JUN 21 2013
...UPDATE TO AVIATION...
.UPDATE...
ISSUED AT 1009 PM CDT THU JUN 20 2013
A FEW RECENT RUNS OF HI RES NEAR TERM MODELS...THE HRRR IN
PARTICULAR...HAVE INDICATED POTENTIAL FOR THUNDERSTORMS OVER
WESTERN KANSAS TO GRADUALLY WORK INTO NORTH CENTRAL KANSAS...AND
PERHAPS CLIPPING THE CONCORDIA AND BELLEVILLE AREAS AROUND
SUNRISE. THE ONGOING DEVELOPMENT IN WESTERN KANSAS AROUND 10 PM
SEEMS TO HAVE BEEN PICKED UP WELL BY THESE MODEL RUNS...AND SEEMS
TO BE LINKED TO A CONVERGENT ZONE ON THE NOSE OF AN INTENSIFYING
LOW LEVEL JET EVIDENT ON DDC WIND PROFILE. WHILE THERE IS AMPLE
INSTABILITY ACROSS MUCH OF CENTRAL AND EASTERN KANSAS...5000 J/KG
SBCAPE WITH THE 00Z TOP SOUNDING...IT ALSO APPEARS TO BE CAPPED
OFF. THE ONLY LIFTING MECHANISM CAPABLE OF OVERCOMING THIS CAP
WOULD SEEM TO BE THE CONVERGENCE ALONG THE NOSE OF THE LLJ. THE
LOCATION OF THIS FAVORED ASCENT IS FORECAST TO EXTEND FROM ITS
CURRENT LOCATION IN WEST CENTRAL KANSAS...UP INTO SOUTH CENTRAL
AND SOUTHEAST NEBRASKA. WITH THAT IN MIND...STILL FEEL PRETTY
COMFORTABLE IN HAVING NO MENTION OF TSTORMS IN THE FORECAST FOR
THE OVERNIGHT AND EARLY MORNING HOURS. HOWEVER...THE 10 TO 14
PERCENT CHANCE OF PRECIP OVER NORTH CENTRAL KANSAS IS THERE FOR A
REASON AS THERE IS STILL A VERY SMALL CHANCE THAT A STORM OR TWO
COULD MOVE INTO THAT REGION AROUND SUNRISE. WILL CONTINUE TO
MONITOR THE SITUATION AND MAKE ADJUSTMENTS IF NEEDED.
BARJENBRUCH
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 305 PM CDT THU JUN 20 2013
20Z WATER VAPOR SHOWS A CLOSED UPPER LOW OVER THE NORTHERN ROCKIES
AND PACIFIC NORTHWEST AND A SHORTWAVE ROUNDING AN UPPER RIDGE AND
MOVING INTO THE UPPER MIDWEST/GREAT LAKES REGION. SREF AND RAP
MODELS SHOW THE UPPER RIDGE OVER THE SOUTHERN PLAINS TO BE GRADUALLY
STRENGTHENING WITH HEIGHTS RISING OVER CENTRAL AND EASTERN KS. AT
THE SURFACE...OBS SHOW A TROUGH AXIS FROM THE SOUTHERN HIGHS PLAINS
NORTH INTO THE NORTHERN PLAINS. THIS HAS CAUSED A STRENGTHENING
SURFACE PRESSURE GRADIENT AND GUSTY SOUTH WINDS ACROSS THE REGION.
FOR TONIGHT AND FRIDAY...THE NAM HAS NOT SHOWN VERY GOOD PERFORMANCE
RECENTLY WITH ITS HANDLING OF CONVECTION. THE OTHER SOLUTIONS
INCLUDING THE GFS/ECMWF/GEM/ARW SUGGEST THAT WITH THE STRENGTHENING
UPPER LEVEL RIDGE ACROSS THE FORECAST AREA PRECIP WILL REMAIN NORTH
AND EAST OF THE FORECAST AREA THROUGH FRIDAY. SO WITH THIS IN MIND
HAVE OPTED TO IGNORE THE NAM SOLUTION AND THE QPF IT BRINGS THROUGH.
THERE DOES NOT APPEAR TO BE ANY STRONG FORCING IN THE FORM OF A
SHORTWAVE OR STRONG ISENTROPIC LIFT OVER THE AREA TO GENERATE
PRECIP...SO THE FORECAST WILL REMAIN DRY THROUGH FRIDAY. LOWS
TONIGHT SHOULD BE QUITE MILD WITH THE STRONG SURFACE PRESSURE
GRADIENT KEEPING WINDS UP THROUGH THE NIGHT. LOWS ARE EXPECTED TO BE
IN THE LOWER TO MID 70S. HIGHS FRIDAY LOOK TO BE RATHER SIMILAR TO
TODAYS BASED ON THE 850 TEMPS OF THE GFS/ECMWF/GEM. WITH THE BOUNDARY
LAYER MIXING TO AROUND 850MB...HIGHS SHOULD BE IN THE LOWER TO MID
90S. WINDS FRIDAY LOOK TO BE QUITE BREEZY ONCE AGAIN WITH THE STRONG
PRESSURE GRADIENT RIGHT OVER THE FORECAST AREA. CONSIDERED THE NEED
FOR A WIND ADVISORY FRIDAY AFTERNOON BUT DECIDED THE LIKELIHOOD OF
ADVISORY LEVEL WINDS WAS NOT HIGH ENOUGH FOR AN ADVISORY AT THIS
TIME. THE NAM IS THE ONLY MODEL THAT HAS A REALLY STRONG PRESSURE
GRADIENT AND SUSTAINED WINDS AROUND 30MPH. SO GIVEN ITS RECENT
TRACK RECORD OVER THE LAST DAY OR TWO...DO NOT FEEL COMFORTABLE
PUTTING MUCH STOCK INTO IT. LATER SHIFTS CAN REEVALUATE.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 305 PM CDT THU JUN 20 2013
FRIDAY NIGHT THROUGH SUNDAY...
FRIDAY NIGHT A FRONTAL BOUNDARY IS EXPECTED TO MOVE INTO NORTHERN
NEBRASKA AND NORTHEAST COLORADO. THUNDERSTORMS MAY DEVELOP ALONG THE
BOUNDARY IN NEBRASKA...BUT ARE EXPECTED TO REMAIN WELL TO THE NORTH
OF THE CWA. THERMAL RIDGE WILL REMAIN IN PLACE ON SATURDAY ACROSS
THE CENTRAL PLAINS. THE UPPER RIDGE OVER THE CENTRAL PLAINS WILL
BREAKDOWN AS A SHORTWAVE TROUGH MOVES ACROSS THE NORTHERN ROCKIES
AND NORTHERN PLAINS. THE FRONTAL BOUNDARY WILL SLIDE A LITTLE
FURTHER SOUTHEAST SATURDAY NIGHT AND SUNDAY. SOME SCATTERED
THUNDERSTORMS ARE POSSIBLE ALONG THE FRONT IN NEBRASKA AND COULD
AFFECT THE NORTHERN CWA. BETTER FORCING WILL REMAIN TO THE NORTH OF
THE CWA. TEMPERATURES WILL REMAIN ON THE HOT SIDE WITH HIGHS IN THE
90S SATURDAY AND SUNDAY. LOWS IN THE LOWER TO MIDDLE 70S ARE
EXPECTED. HEAT INDICES IN THE UPPER 90S TO LOW 100S ARE POSSIBLE
EACH DAY.
SUNDAY NIGHT THROUGH THURSDAY...
ON SUNDAY THE MAIN SHORTWAVE TROUGH WILL BE LIFTING NORTHEAST
THROUGH THE NORTHERN PLAINS WHILE THE TRAILING FRONT PUSHES SOUTH
INTO EASTERN NEBRASKA AND WESTERN KANSAS. MEANWHILE AN EMBEDDED
SHORTWAVE IN THE SOUTHWEST FLOW WILL SLIDE ACROSS THE REGION
AIDING IN THUNDERSTORM DEVELOPMENT ALONG AND NEAR THE SFC FRONT.
IT DOES APPEAR THAT THE BETTER CHANCES FOR STORMS WILL BE ACROSS
AREAS NORTH OF INTERSTATE 70 SUNDAY NIGHT. AN UPPER LEVEL RIDGE
WILL THEN BUILD OVER THE PLAINS CAUSING HIGH TEMPERATURES TO REACH
THE MID TO UPPER 90S WITH HEAT INDICES IN THE LOW 100S MONDAY
THROUGH THE PERIOD. THE RIDGE WILL CONTINUE TO BUILD MORE ACROSS
THE WESTERN US WHICH WILL ALLOW THE LONGWAVE TROUGH TO DIG SOUTH
ACROSS THE EASTERN US. THIS WILL BRING A FRONT INTO THE REGION ON
WEDNESDAY AND THURSDAY INCREASES CHANCES FOR PRECIP.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1156 PM CDT THU JUN 20 2013
VFR CONDITIONS ARE FORECAST THROUGH THE TAF PERIOD. EXPECT TO
REMAIN BELOW LLWS CRITERIA TONIGHT BUT 1000 FT WINDS WILL BE
STRONG AT 45 TO 50 KTS. WILL SEE SURFACE GUSTS OF 25 TO 30 KTS
THROUGH THE DAY ON FRIDAY.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BARJENBRUCH
SHORT TERM...WOLTERS
LONG TERM...SANDERS/WOYNICK
AVIATION...BARJENBRUCH
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
300 AM EDT FRI JUN 21 2013
.UPDATE...
ISSUED AT 122 AM EDT FRI JUN 21 2013
WILL ALLOW FOR A DRY FORECAST ACROSS THE ENTIRE AREA FOR THE REST OF
THE OVERNIGHT AS RADAR TRENDS HAVE SHOWED A CONTINUED GRADUAL
DISSIPATION OF THE CONVECTION NEAR THE KY/TN/VA BORDERS. ALSO
FRESHENED UP THE HOURLY TEMPERATURES...DEW POINTS...AND SKY COVER
ACCORDING TO THE LATEST TRENDS IN OBSERVATIONS.
UPDATE ISSUED AT 941 PM EDT THU JUN 20 2013
VERY FEW CHANGES NEEDED TO THE FORECAST TONIGHT. STORMS BACK-
BUILDING INTO WISE COUNTY VA MAY SNEAK BACK INTO HARLAN AND LETCHER
COUNTIES OVER THE NEXT HOUR OR TWO SO WILL MAINTAIN A SMALL CHANCE
OF A STORM THERE FOR A FEW MORE HOURS WITH DRY CONDITIONS
ANTICIPATED FOR THE REST OF THE AREA TONIGHT. FORECAST LOWS A COUPLE
DEGREES WARMER THAN LAST NIGHT APPEAR ON TARGET SO NO CHANGES THERE.
HAVE A GOOD NIGHT...
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 323 PM EDT THU JUN 20 2013
AS OF MID AFTERNOON...A RIDGE OF HIGH PRESSURE WAS CENTERED OVER
NORTHERN MEXICO AND THE SOUTHERN PLAINS WITH RIDGING EXTENDING NORTH
THROUGH THE PLAINS AND GENERAL RIDGING SOUTHEAST INTO THE GULF OF
MEXICO. MEANWHILE...A SHORTWAVE IS WORKING THROUGH THE OH VALLEY WITH
WEAK TROUGHING IN PLACE OVER THE LOWER OH VALLEY AND TN VALLEY REGION
INTO THE SOUTHEAST. AF THE SFC...HIGH PRESSURE WAS CENTERED OVER THE
NORTHEASTERN CONUS WITH RIDGING SOUTHWEST INTO THE OH VALLEY.
CONVECTION SO FAR HAS GENERALLY BEEN CONFINED TO THE NORTHERN
CUMBERLAND PLATEAU OF TN INTO THE LAKE CUMBERLAND REGION.
FOR THE REMAINDER OF THIS AFTERNOON AND INTO THIS EVENING...
CONVECTION SHOULD CONTINUE TO DEVELOP ALONG THE TN AND VA BORDERS
AS THE SHORTWAVE WORKS ACROSS THE OH VALLEY. CONVECTION SHOULD WANE
THROUGH THE EVENING WITH LOSS OF DAYTIME HEATING WITH CU DISSIPATING
DURING THAT TIME AS WELL. AREAS OF VALLEY FOG SHOULD DEVELOP TONIGHT
WITH DEWPOINTS AROUND 60 OR IN THE LOWER 60S AND A RELATIVELY WEAK
PRESSURE GRADIENT IN PLACE. SOME OF THIS WILL ALMOST CERTAINLY BECOME
DENSE IN THE RIVER VALLEYS...ESPECIALLY IN THE BIG SANDY REGION. POPS
FOR THE REMAINDER OF THE AFTERNOON INTO THE EVENING WERE RELATIVELY
UNCHANGED AS RECENT TRENDS ARE GENERALLY SUPPORTIVE OF THESE WHEN
CONSIDERED WITH RECENT MODEL GUIDANCE INCLUDING RECENT HRRR RUNS THAT
EVENTUALLY DEVELOP CONVECTION NEAR THE VA BORDER AND THEN HAVE A
COUPLE OF GENERATIONS OF IT WORKING TOWARD THE NORTHWEST OVER THE
SOUTHEASTERN COUNTIES.
THE REGION WILL BE IN A GENERAL WEAKNESS BETWEEN RIDGING OVER THE
ATLANTIC AND OVER THE MS VALLEY REGION WHILE A WEAK UPPER LEVEL LOW
IS PROGGED OVER THE SOUTHEASTERN STATES FOR FRI AND FRI NIGHT.
GENERALLY DIURNALLY DRIVEN CONVECTION IS ANTICIPATED FRI AFTERNOON
INTO FRI EVENING AS THERE ARE NO OTHER REAL TRIGGERS. SLIGHT CHANCE
POPS WERE USED FOR ALL AREAS ALONG SOUTH OF INTERSTATE 64 WITH A
LITTLE BIT OF CHANCE OVER THE HIGHEST TERRAIN ALONG THE VA BORDER.
PATCHY VALLEY FOG IS AGAIN FAVORED WITH SFC HIGH PRESSURE CENTERED TO
OUR EAST AND NORTHEAST WITH RELATIVELY HIGH DEWPOINTS AND A WEAK
PRESSURE GRADIENT. MUCH OF THE CLOUD COVER SHOULD THIN ON FRI NIGHT
WITH LOSS OF DAYTIME HEATING.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 300 AM EDT FRI JUN 21 2013
THE MODELS BEGIN THE EXTENDED WITH PRETTY GOOD AGREEMENT ALOFT AS
THE WESTERLIES ARE WELL TO THE NORTH OF THE AREA WHILE GENERALLY
WEAK RIDGING IS FOUND THROUGH THE SOUTHEAST THIRD OF THE NATION.
EMBEDDED WITHIN THIS RIDGE IS A WEAKNESS CENTERED OVER THE NORTHERN
GEORGIA AND ALABAMA LINE. THIS LOCALIZED AREA OF LOWER HEIGHTS WILL
OPEN UP AND DRIFT NORTHEAST THROUGH THE LATTER PART OF THE WEEKEND
AND START OF THE NEXT WORK 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 AND GEM. BY MONDAY NIGHT...
THIS AREA OF WEAKNESS WILL HAVE SUPPRESSED THIS PART OF THE RIDGE AS
ITS CORE STARTS TO PUSH MORE WESTERLY...MAKING FOR LOWER HEIGHTS FOR
OUR AREA AND A BIT BETTER INTERACTION WITH THE WESTERLIES AREA...
STILL RUNNING MAINLY NORTH OF THE GREAT LAKES. LOWER HEIGHTS ON THE
NORTHEAST SIDE OF THE...NOW SOUTHWEST...RIDGE WILL BE THE RULE
THROUGH THE MIDDLE OF NEXT WEEK AS THE MID LEVEL WAVES MOVING BY TO
THE NORTH PASS INCREASINGLY CLOSER TO EASTERN KENTUCKY. AS THE RIDGE
RETROGRADES FURTHER WEST AND THEN NORTH...BUILDING AS IT DOES...THE
SOUTHERN MOST OF THESE WAVES LOOKS TO CROSS THROUGH THE OHIO VALLEY
ON THURSDAY...IN THE ECMWF. MEANWHILE...THE GFS TAKES A PROPER
TROUGH INTO THE UPPER MIDWEST AND DROPS ITS INFLUENCE SOUTHEAST INTO
AND THROUGH THE BREADTH OF THE OHIO VALLEY BY THURSDAY EVENING. FOR
NOW WILL LEAN TOWARD THE MORE PROGRESSIVE ECMWF SOLUTION...THOUGH
BOTH ARE HINTING AT A DECENT PATTERN ADJUSTMENT WROUGHT BY THE
BUILDING RIDGE OVER THE CENTRAL AND SOUTHERN ROCKIES TOWARD THE END
OF 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 CONVECTION ONCE THE DAYTIME HEATING TAKES HOLD.
EVEN SO...THERE REALLY IS NO FEATURE TO KEY IN ON FOR MORE
WIDESPREAD OR ORGANIZED ACTIVITY THROUGH THE START OF THE NEW WORK
WEEK. THAT CHANGES BY WEDNESDAY AS FALLING HEIGHTS AND ENERGY FROM
THE WESTERLIES AT MID LEVELS SHOULD BE ENOUGH TO HELP GENERATE
BETTER CLUSTERS OF STORMS FOR OUR AREA...THOUGH TIMING AND SPECIFICS
REMAIN IN DOUBT. WARM AND SEASONABLE WEATHER IS THUS ON TAP FOR THE
REST OF THE WEEKEND THROUGH THE START OF THE NEW WORK WEEK BEFORE A
LITTLE MORE CLOUDS AND CONVECTION FROM MID WEEK ON...TEMPER THE
WARMTH A BIT.
THE CR GRID LOAD CAME IN A BIT HEAVY ON THE POPS...ESPECIALLY EARLY.
DID MAKE HOURLY ADJUSTMENTS TO THE POPS AND SKY COVER TO BETTER
REFLECT THE TIMES OF PEAK CONVECTION SUNDAY INTO TUESDAY. ALSO MADE
SOME FINE TUNE ADJUSTMENTS TO TEMPERATURES EACH NIGHT BASED ON
RELATIVE ELEVATIONAL DIFFERENCES FROM SATURDAY NIGHT THROUGH MONDAY
NIGHT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 122 AM EDT FRI JUN 21 2013
SURFACE HIGH PRESSURE WILL PROVIDE FOR MAINLY VFR CONDITIONS AND
LIGHT WINDS ACROSS THE AREA THROUGH THE PERIOD. THERE WILL BE SOME
IFR OR WORSE FOG TO CONTEND WITH IN THE DEEPER RIVER
VALLEYS THROUGH 13 OR 14Z...HOWEVER EXPECT THIS TO STEER CLEAR OF
THE TAF SITES...WITH PERHAPS JUST SOME TEMPORARY MVFR BETWEEN 10 AND
12Z AT SME AND LOZ. DURING PEAK HEATING...A FEW SHOWERS AND STORMS WILL
ALSO THREATEN THE AREA...HOWEVER THE COVERAGE LOOKS TO BE TOO LIMITED
TO INCLUDE A MENTION IN THE TAFS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...JP
LONG TERM...GREIF
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
122 AM EDT FRI JUN 21 2013
.UPDATE...
ISSUED AT 122 AM EDT FRI JUN 21 2013
WILL ALLOW FOR A DRY FORECAST ACROSS THE ENTIRE AREA FOR THE REST OF
THE OVERNIGHT AS RADAR TRENDS HAVE SHOWED A CONTINUED GRADUAL
DISSIPATION OF THE CONVECTION NEAR THE KY/TN/VA BORDERS. ALSO
FRESHENED UP THE HOURLY TEMPERATURES...DEW POINTS...AND SKY COVER
ACCORDING TO THE LATEST TRENDS IN OBSERVATIONS.
UPDATE ISSUED AT 941 PM EDT THU JUN 20 2013
VERY FEW CHANGES NEEDED TO THE FORECAST TONIGHT. STORMS BACK-
BUILDING INTO WISE COUNTY VA MAY SNEAK BACK INTO HARLAN AND LETCHER
COUNTIES OVER THE NEXT HOUR OR TWO SO WILL MAINTAIN A SMALL CHANCE
OF A STORM THERE FOR A FEW MORE HOURS WITH DRY CONDITIONS
ANTICIPATED FOR THE REST OF THE AREA TONIGHT. FORECAST LOWS A COUPLE
DEGREES WARMER THAN LAST NIGHT APPEAR ON TARGET SO NO CHANGES THERE.
HAVE A GOOD NIGHT...
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 323 PM EDT THU JUN 20 2013
AS OF MID AFTERNOON...A RIDGE OF HIGH PRESSURE WAS CENTERED OVER
NORTHERN MEXICO AND THE SOUTHERN PLAINS WITH RIDGING EXTENDING NORTH
THROUGH THE PLAINS AND GENERAL RIDGING SOUTHEAST INTO THE GULF OF
MEXICO. MEANWHILE...A SHORTWAVE IS WORKING THROUGH THE OH VALLEY WITH
WEAK TROUGHING IN PLACE OVER THE LOWER OH VALLEY AND TN VALLEY REGION
INTO THE SOUTHEAST. AF THE SFC...HIGH PRESSURE WAS CENTERED OVER THE
NORTHEASTERN CONUS WITH RIDGING SOUTHWEST INTO THE OH VALLEY.
CONVECTION SO FAR HAS GENERALLY BEEN CONFINED TO THE NORTHERN
CUMBERLAND PLATEAU OF TN INTO THE LAKE CUMBERLAND REGION.
FOR THE REMAINDER OF THIS AFTERNOON AND INTO THIS EVENING...
CONVECTION SHOULD CONTINUE TO DEVELOP ALONG THE TN AND VA BORDERS
AS THE SHORTWAVE WORKS ACROSS THE OH VALLEY. CONVECTION SHOULD WANE
THROUGH THE EVENING WITH LOSS OF DAYTIME HEATING WITH CU DISSIPATING
DURING THAT TIME AS WELL. AREAS OF VALLEY FOG SHOULD DEVELOP TONIGHT
WITH DEWPOINTS AROUND 60 OR IN THE LOWER 60S AND A RELATIVELY WEAK
PRESSURE GRADIENT IN PLACE. SOME OF THIS WILL ALMOST CERTAINLY BECOME
DENSE IN THE RIVER VALLEYS...ESPECIALLY IN THE BIG SANDY REGION. POPS
FOR THE REMAINDER OF THE AFTERNOON INTO THE EVENING WERE RELATIVELY
UNCHANGED AS RECENT TRENDS ARE GENERALLY SUPPORTIVE OF THESE WHEN
CONSIDERED WITH RECENT MODEL GUIDANCE INCLUDING RECENT HRRR RUNS THAT
EVENTUALLY DEVELOP CONVECTION NEAR THE VA BORDER AND THEN HAVE A
COUPLE OF GENERATIONS OF IT WORKING TOWARD THE NORTHWEST OVER THE
SOUTHEASTERN COUNTIES.
THE REGION WILL BE IN A GENERAL WEAKNESS BETWEEN RIDGING OVER THE
ATLANTIC AND OVER THE MS VALLEY REGION WHILE A WEAK UPPER LEVEL LOW
IS PROGGED OVER THE SOUTHEASTERN STATES FOR FRI AND FRI NIGHT.
GENERALLY DIURNALLY DRIVEN CONVECTION IS ANTICIPATED FRI AFTERNOON
INTO FRI EVENING AS THERE ARE NO OTHER REAL TRIGGERS. SLIGHT CHANCE
POPS WERE USED FOR ALL AREAS ALONG SOUTH OF INTERSTATE 64 WITH A
LITTLE BIT OF CHANCE OVER THE HIGHEST TERRAIN ALONG THE VA BORDER.
PATCHY VALLEY FOG IS AGAIN FAVORED WITH SFC HIGH PRESSURE CENTERED TO
OUR EAST AND NORTHEAST WITH RELATIVELY HIGH DEWPOINTS AND A WEAK
PRESSURE GRADIENT. MUCH OF THE CLOUD COVER SHOULD THIN ON FRI NIGHT
WITH LOSS OF DAYTIME HEATING.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 339 PM EDT THU JUN 20 2013
THE LONG TERM STARTS OUT ON SATURDAY WITH AN UPPER RIDGE DOMINATING
THE SOUTHEAST COAST WITH A RESIDUAL WEAK CUTOFF UPPER LOW LOCATED
NEAR THE AL-TN-GA BORDER. CONFIDENCE IN THE FORECAST IS VERY LOW
BECAUSE THE MODELS REALLY DO NOT DO VERY WELL WITH THESE RESIDUAL
LOWS THIS TIME OF THE YEAR. THE FORECAST POSITIONS CAN BE VASTLY
DIFFERENT BASED ON THE POSITION OF THE UPPER LOW...AS IT CAN BRING
WITH IT INCREASED INSTABILITY AND A GREATER CHANCE FOR
PRECIPITATION. IN GENERAL...CONDITIONS WILL BE WARM WITH LOTS OF
CONVECTIVE ACTIVITY. THE THUNDER SHOULD TEND TO HAVE AN AFTERNOON
AND EARLY EVENING MAXIMUM...HOWEVER AN ISOLATED STORM MAY CONTINUE
INTO THE OVERNIGHT HOURS. SOME OF THE STORMS MAY BECOME STRONG
HOWEVER SHOULD STAY BELOW SEVERE CRITERIA. IN PLACES WHERE
THUNDERSTORMS DO OCCUR...THERE COULD BE SOME LOCALIZED HIGH WATER
WITH DITCHES AND LOW WATER CROSSINGS RUNNING FULL DUE TO THE VERY
SLOW MOVEMENT OF THE STORMS. TEMPERATURES WILL CONTINUE TO BE VERY
SEASONAL WITH HIGH TEMPERATURES STAYING IN THE MID 80S. THIS PATTERN
SHOULD CONTINUE THROUGH THE END OF THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 122 AM EDT FRI JUN 21 2013
SURFACE HIGH PRESSURE WILL PROVIDE FOR MAINLY VFR CONDITIONS AND
LIGHT WINDS ACROSS THE AREA THROUGH THE PERIOD. THERE WILL BE SOME
IFR OR WORSE FOG TO CONTEND WITH IN THE DEEPER RIVER
VALLEYS THROUGH 13 OR 14Z...HOWEVER EXPECT THIS TO STEER CLEAR OF
THE TAF SITES...WITH PERHAPS JUST SOME TEMPORARY MVFR BETWEEN 10 AND
12Z AT SME AND LOZ. DURING PEAK HEATING...A FEW SHOWERS AND STORMS WILL
ALSO THREATEN THE AREA...HOWEVER THE COVERAGE LOOKS TO BE TOO LIMITED
TO INCLUDE A MENTION IN THE TAFS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...JP
LONG TERM...JJ
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
744 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 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 743 PM EDT SAT JUN 22 2013
WITH ABUNDANT LOW-LEVEL MOISTURE LINGERING OVER THE REGION TO THE N
OF A WARM FRONT...IFR/LIFR CONDITIONS ARE LIKELY TO SET IN AGAIN
TONIGHT AT KCMX/KSAW AS BOTH OF THESE TERMINALS WILL ALSO HAVE A
LIGHT UPSLOPE WIND. WITH WINDS VEERING AROUND TO A DOWNSLOPE SE/S
DIRECTION AT KIWD...CONDITIONS THERE SHOULD NOT FALL BLO MVFR.
DAYTIME HEATING COMBINED WITH WARM FRONT LIFTING N OF THE AREA SUN
WILL RESULT IN ALL TERMINALS IMPROVING TO VFR. AS FOR PCPN...
SHRA/TSRA POTENTIAL REMAINS VERY UNCERTAIN. THERE IS SOME POTENTIAL
FOR SHRA/TSRA LATE TONIGHT/SUN MORNING AS WARM FRONT LIFTS N ACROSS
THE AREA...AND THEN PERHAPS MID/LATE SUN AFTN AS INSTABILITY BUILDS
IN WARM/HUMID AIR MASS. HOWEVER...SINCE CONFIDENCE IN
COVERAGE/LOCATION OF ANY CONVECTION THAT MIGHT DEVELOP IS VERY
LOW...DID NOT INCLUDE A MENTION OF SHRA/TSRA IN THIS FCST 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...ROLFSON
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
455 AM EDT FRI JUN 21 2013
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 431 PM EDT THU JUN 20 2013
UPPER AIR PATTERN FEATURES DEEP TROUGHING OVER NORTHWEST CONUS WITH
RIDGING DOWNSTREAM OVER NORTHERN PLAINS. SFC FRONT WITH DRIER AIR IS
WORKING ACROSS DAKOTAS WITH WEAK SFC LOW OVR NCNTRL SD BTWN KBIS AND
KABR. BASED ON SFC OBS AND VIS SATELLITE APPEARS WARM FRONT EXTENDS
FROM SFC LOW ACROSS CNTRL MN AND INTO NORTHWEST WI. NOT MUCH OF A
TEMP GRADIENT AT H85 BUT RIBBON OF HIGHER H85-H7 DWPNT ALONG WITH
H85 CONVERGENCE FROM NORTHERN MN ACROSS UPR MICHIGAN IS SERVING AS
FOCUS WAVE AFTER WAVE OF SCT SHRA/ISOLD TSRA. NO STRONG TSTM THOUGH
AS CAPE AVAILABLE OVR THE AREA IS BLO 1000 J/KG. DEEP LAYER SHEAR IS
MARGINAL AS WELL...MAYBE UP TO 30 KTS. STRONGEST CONVECTION TODAY
HAVE HAD LIGHTNING BUT HAVE REALLY SHOWN LITTLE TILT OWING TO THE
LIMITED INSTABILITY/SHEAR.
BASED ON WV LOOP/LIGHTNING AND RUC ANALYSIS...DOES SEEM THAT THERE
IS ONE WEAKER SHORTWAVE OVER NORTHWEST WI...ANOTHER NEAR THE DLH
AREA...AND A STRONGER WAVE LIFTING ENE ACROSS NORTHEAST ND. EXPECT
ISOLD-SCATTERED SHRA AND TSRA OVR CWA THROUGH EVENING...ESPECIALLY
NORTHERN HALF...AS THESE WAVES SLIDE THROUGH ALONG THE BOUNDARY AT
H85. OVERALL...LIMITED INSTABILITY SHOULD PRECLUDE STRONGER STORMS
THIS EVENING OVR MUCH OF CWA. EXCEPTION MAY BE IN FAR SW VCNTY OF
IWD AS MLCAPE BUILDING UP OVER 1000J/KG JUST TO SOUTHWEST OF WEST
CWA AND SWRLY STORM MOTION COULD RESULT IN STRONGER STORM WITH GUSTY
WINDS AND HAIL. THUS FAR NO REAL INDICATIONS OF THIS WITH UPSTREAM
STORMS BUT IT IS SOMETHING TO WATCH.
LATER TONIGHT...MAIN QUESTION IS WHAT WILL OCCUR WITH UPSTREAM
CONVECTION. IN A NUTSHELL...APPEARS THAT IF PRIMARY AREA OF
CONVECTIVE DEVELOPING THROUGH EARLY EVENING OCCURS ALONG AND EAST OF
SFC LOW...850-300MB THICKNESS/ORIENTATION OF HIGHEST MUCAPE/FORWARD
PROPAGATING CORFIDI VECTORS POINT TO MAIN TRACK OF SHRA/TSRA COMPLEX
OR BONIFIDE MCS MAINLY STAYING SOUTH OF CWA...WOULD BE CLOSE IN THE
SOUTHWEST CWA THOUGH. ON THE OTHER HAND...IF CONVECTION OVR
NORTHEAST ND CONTINUES TO DRIFT ACROSS RIDGE TOP IT COULD ADVECT
AND/OR SPUR ON ADDITIONAL SHRA/TSRA OVERNIGHT IN NORTHERN MN AND
BASED ON 850-300MB THICKNESSES...SHRA/TSRA WOULD TRACK INTO FAR
WESTERN UPR MICHIGAN 08Z-12Z. INCREASING SFC-ML CAPES AND 0-1KM
SHEAR UP TO 20 KTS AND BOW-LIKE APPEARANCE FROM VARIOUS HIGHER
RESOLUTION MODELS INDICATE IF THIS CONVECTION IMPACTS WESTERN CWA
THERE COULD BE STRONG WIND GUSTS. WITH ALL THE CLOUD COVER AND
POSSIBLE SHRA/TSRA WILL BE A WARM NIGHT WITH LOWS IN THE MID 50S
EAST AND STAYING ABOVE 60 DEGREES OVER THE WEST.
FOR FRIDAY...CONDITIONAL FORECAST FOR SURE. IF THE SHRA/TSRA ARE
AROUND IN THE MORNING...EXPECT A GENERAL LULL LATE MORNING INTO MOST
OF THE AFTN DUE TO THE SUBSIDENCE IN WAKE OF THE CONVECTION. MIXING
TO H9 WOULD SUPPORT HIGHS WELL INTO THE 70S IF NOT REACHING 80 WITH
ENOUGH SUNSHINE. AFTN INSTABILITY AND WARM FRONT/OUTFLOW IN THE VCNTY
COULD LEAD TO MORE DEVELOPING SHRA/TSRA MID-LATE AFTN. LOW CHANCE
POPS FOR ALL AREAS AFTER THE MAIN SHRA/TSRA CHANCES IN THE MORNING.
BEST CHANCE IN THE AFTN WOULD PROBABLY BE IN THE WEST/SOUTHWEST CWA
WITH BETTER SHOT OF EARLIER CLEARING/WARMER TEMPERATURES. HUMID
CONDITIONS THAT HAVE DEVELOPED TODAY WILL CONTINUE THROUGH FRIDAY
WITH DWPNTS STAYING AT OR ABOVE 60 IN MANY AREAS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 431 AM EDT FRI JUN 21 2013
UPPER AIR PATTERN CONSISTS OF A 500 MB TROUGH OVER THE WESTERN U.S.
AND A SHORTWAVE OVER THE UPPER MISSISSIPPI RIVER VALLEY WITH A RIDGE
OVER THE UPPER GREAT LAKES 12Z SAT. THE TROUGH AND SHORTWAVE MOVE
THROUGH THE AREA THIS WEEKEND AND WILL BRING UNSETTLED WEATHER TO
THE AREA. THIS IS GOING TO BE HARD TO TIME ANY LITTLE WAVES THAT
MOVE THROUGH THE AREA. WITH A FRONT IN THE AREA...HARD TO TIME POPS
AND WILL CONTINUE WITH THE CHANCE POPS THAT WERE IN THERE. ONE THING
I DID DO THOUGH WAS RAISE HIGH TEMPERATURES A BIT FOR SAT AND
SUNDAY. 850 MB TEMPERATURES ALOFT GET CLOSE TO 20C AND MIXING THIS
DOWN TO THE SFC GIVES ME HIGHS NEAR 90 ON SUNDAY. WENT LOWER 80S ON
SATURDAY AND MID TO UPPER 80S ON SUNDAY. ANY SUNSHINE WILL HELP WARM
THE TEMPERATURES UP AND AGAIN DO NOT THINK BOTH DAYS WILL BE
WASHOUTS BY ANY MEANS. BROADBRUSHING CHANCE POPS LOOKS GOOD FOR BOTH
DAYS. OTHERWISE...NO MAJOR CHANGES TO THE GOING FORECAST. LOOKS
HUMID AND WARM AS WELL.
IN THE EXTENDED...GFS AND ECMWF SHOW A BROAD 500 MB RIDGE ACROSS THE
SOUTHERN AND EASTERN U.S. 12Z MON WITH A DEEP TROUGH ACROSS THE
WESTERN U.S. THERE IS ALSO A SHORTWAVE TROUGH MOVING THROUGH SOUTH
CENTRAL CANADA AT THAT TIME. THIS SHORTWAVE HELPS TO FLATTEN THE
RIDGE A BIT OVER THE AREA AND CONTINUE TO PUT THE AREA IN THE RING
OF FIRE CONVECTION SCENARIO ON THE EDGE OF THE RIDGE. ANY SHORTWAVE
THAT MOVES THROUGH HAS THE POTENTIAL TO KICK OFF SOME SHOWERS AND
THUNDERSTORMS. UPPER PATTERN THEN EVOLVES INTO A RIDGE ACROSS THE
ROCKIES ON THU WITH TROUGHING OVER THE UPPER GREAT LAKES THEN WITH
AREA STILL IN THE RING OF FIRE SCENARIO THEN. LOOKS PRETTY UNSETTLED
THROUGH THIS EXTENDED PERIOD ALONG WITH SOME WARMER WEATHER AND
ABOVE NORMAL TEMPERATURES AND HUMIDITY THIS FORECAST PERIOD. TRYING
TO TIME THE PERIODS OF CONVECTION WILL BE DIFFICULT AND DO NOT THINK
THE WHOLE TIME WILL BE A WASHOUT EITHER AS THERE WILL BE SOME BRIEF
DRY PERIODS IN THERE. BROADBRUSHING CHANCE POPS FOR THE PERIOD LOOKS
GOOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1212 AM EDT FRI JUN 21 2013
WILL BE A CHALLENGING FCST THRU THIS PERIOD DUE TO UNCERTAINTIES IN
CONVECTION AND LOW CLOUDS/FOG. INITIALLY...AS EXPECTED...MAIN AREAS
OF TSRA SO FAR TONIGHT HAVE BEEN SLIDING SE TO THE S OF THE AREA AS
CONVECTION FOLLOWS 850-300MB THICKNESS PATTERN. SHRA FARTHER N THAT
HAVE BEEN AFFECTING KIWD/KCMX/KSAW SHOULD DIMINISH FOR A WHILE. AT
KCMX...COOL EASTERLY UPSLOPE FLOW OFF LAKE SUPERIOR INTO HIGHER DWPT
AIR MASS OVER THE KEWEENAW HAS RESULTED IN LIFR CONDITIONS...AND
LIFR WILL LINGER THRU THE NIGHT UNDER CONTINUED LIGHT EASTERLY
WINDS. AT KSAW...WITH -SHRA DIMINISHING...FOG/MVFR CONDITIONS SHOULD
PREVAIL OVERNIGHT. NOT OUT OF THE QUESTION THAT CONDITIONS COULD
FALL TO IFR WITH FOG/STRATUS. DOWNSLOPE E/SE WINDS SHOULD ALLOW VFR
CONDITIONS OVERNIGHT AT KIWD THOUGH MVFR WILL OCCUR WITH ANY
SHRA/TSRA. LATER IN THE NIGHT...DISTURBANCE EMERGING FROM THE NRN
PLAINS SHOULD SUPPORT A MORE ORGANIZED CLUSTER OF SHRA/TSRA
SPREADING TOWARD THE AREA. GIVEN ARRIVAL DURING THE MORNING IN THE
USUAL DIURNAL MIN FOR CONVECTION...TSRA POTENTIAL SHOULD BE MORE
LIMITED. INCLUDED MVFR CONDITIONS WITH SHRA/VCTS AT KIWD...BUT JUST
SHRA AT KCMX/KSAW. AFTER A FEW HRS OF PCPN...CONDITIONS SHOULD BREAK
OUT TO VFR AT KIWD/KSAW...BUT MAY RETURN TO IFR UNDER CONTINUED COOL
UPSLOPE EASTERLY FLOW AT KCMX. EXPECT A BREAK OUT TO VFR AT KCMX IN
THE AFTN. ADDITIONAL CONVECTIVE DEVELOPMENT THIS AFTN/EVENING IS
UNCERTAIN. FOR NOW...WILL PLAN FOR A MORE LIKELY DRY SCENARIO IN THE
WAKE OF SHORTWAVE PASSING IN THE MORNING/EARLY AFTN. FOG MVFR
CONDITIONS MAY DEVELOP THIS EVENING AT KIWD/KSAW WHILE COOL EASTERLY
UPSLOPE FLOW ARGUES FOR A RETURN TO LIFR AT KCMX.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 455 AM EDT FRI JUN 21 2013
WINDS SHOULD REMAIN AROUND 25KTS OR LESS...WITH THE MAIN THREAT
BEING SHOWERS AND THUNDERSTORMS...AND FOG THROUGH THE ENTIRE PERIOD.
WHILE THE PRESSURE WILL ONLY CHANGE MARGINALLY THROUGH TUESDAY...A
TROUGH OF LOW PRESSURE WILL BE OVER OR NEAR LAKE SUPERIOR...WITH
STRONGER LOW PRESSURE TO OUR WEST PUSHING ROUNDS OF MOIST UNSTABLE
AIR NORTHWARD ACROSS THE GREAT LAKES REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLA
LONG TERM...07
AVIATION...ROLFSON
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
431 AM EDT FRI JUN 21 2013
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 431 PM EDT THU JUN 20 2013
UPPER AIR PATTERN FEATURES DEEP TROUGHING OVER NORTHWEST CONUS WITH
RIDGING DOWNSTREAM OVER NORTHERN PLAINS. SFC FRONT WITH DRIER AIR IS
WORKING ACROSS DAKOTAS WITH WEAK SFC LOW OVR NCNTRL SD BTWN KBIS AND
KABR. BASED ON SFC OBS AND VIS SATELLITE APPEARS WARM FRONT EXTENDS
FROM SFC LOW ACROSS CNTRL MN AND INTO NORTHWEST WI. NOT MUCH OF A
TEMP GRADIENT AT H85 BUT RIBBON OF HIGHER H85-H7 DWPNT ALONG WITH
H85 CONVERGENCE FROM NORTHERN MN ACROSS UPR MICHIGAN IS SERVING AS
FOCUS WAVE AFTER WAVE OF SCT SHRA/ISOLD TSRA. NO STRONG TSTM THOUGH
AS CAPE AVAILABLE OVR THE AREA IS BLO 1000 J/KG. DEEP LAYER SHEAR IS
MARGINAL AS WELL...MAYBE UP TO 30 KTS. STRONGEST CONVECTION TODAY
HAVE HAD LIGHTNING BUT HAVE REALLY SHOWN LITTLE TILT OWING TO THE
LIMITED INSTABILITY/SHEAR.
BASED ON WV LOOP/LIGHTNING AND RUC ANALYSIS...DOES SEEM THAT THERE
IS ONE WEAKER SHORTWAVE OVER NORTHWEST WI...ANOTHER NEAR THE DLH
AREA...AND A STRONGER WAVE LIFTING ENE ACROSS NORTHEAST ND. EXPECT
ISOLD-SCATTERED SHRA AND TSRA OVR CWA THROUGH EVENING...ESPECIALLY
NORTHERN HALF...AS THESE WAVES SLIDE THROUGH ALONG THE BOUNDARY AT
H85. OVERALL...LIMITED INSTABILITY SHOULD PRECLUDE STRONGER STORMS
THIS EVENING OVR MUCH OF CWA. EXCEPTION MAY BE IN FAR SW VCNTY OF
IWD AS MLCAPE BUILDING UP OVER 1000J/KG JUST TO SOUTHWEST OF WEST
CWA AND SWRLY STORM MOTION COULD RESULT IN STRONGER STORM WITH GUSTY
WINDS AND HAIL. THUS FAR NO REAL INDICATIONS OF THIS WITH UPSTREAM
STORMS BUT IT IS SOMETHING TO WATCH.
LATER TONIGHT...MAIN QUESTION IS WHAT WILL OCCUR WITH UPSTREAM
CONVECTION. IN A NUTSHELL...APPEARS THAT IF PRIMARY AREA OF
CONVECTIVE DEVELOPING THROUGH EARLY EVENING OCCURS ALONG AND EAST OF
SFC LOW...850-300MB THICKNESS/ORIENTATION OF HIGHEST MUCAPE/FORWARD
PROPAGATING CORFIDI VECTORS POINT TO MAIN TRACK OF SHRA/TSRA COMPLEX
OR BONIFIDE MCS MAINLY STAYING SOUTH OF CWA...WOULD BE CLOSE IN THE
SOUTHWEST CWA THOUGH. ON THE OTHER HAND...IF CONVECTION OVR
NORTHEAST ND CONTINUES TO DRIFT ACROSS RIDGE TOP IT COULD ADVECT
AND/OR SPUR ON ADDITIONAL SHRA/TSRA OVERNIGHT IN NORTHERN MN AND
BASED ON 850-300MB THICKNESSES...SHRA/TSRA WOULD TRACK INTO FAR
WESTERN UPR MICHIGAN 08Z-12Z. INCREASING SFC-ML CAPES AND 0-1KM
SHEAR UP TO 20 KTS AND BOW-LIKE APPEARANCE FROM VARIOUS HIGHER
RESOLUTION MODELS INDICATE IF THIS CONVECTION IMPACTS WESTERN CWA
THERE COULD BE STRONG WIND GUSTS. WITH ALL THE CLOUD COVER AND
POSSIBLE SHRA/TSRA WILL BE A WARM NIGHT WITH LOWS IN THE MID 50S
EAST AND STAYING ABOVE 60 DEGREES OVER THE WEST.
FOR FRIDAY...CONDITIONAL FORECAST FOR SURE. IF THE SHRA/TSRA ARE
AROUND IN THE MORNING...EXPECT A GENERAL LULL LATE MORNING INTO MOST
OF THE AFTN DUE TO THE SUBSIDENCE IN WAKE OF THE CONVECTION. MIXING
TO H9 WOULD SUPPORT HIGHS WELL INTO THE 70S IF NOT REACHING 80 WITH
ENOUGH SUNSHINE. AFTN INSTABILITY AND WARM FRONT/OUTFLOW IN THE VCNTY
COULD LEAD TO MORE DEVELOPING SHRA/TSRA MID-LATE AFTN. LOW CHANCE
POPS FOR ALL AREAS AFTER THE MAIN SHRA/TSRA CHANCES IN THE MORNING.
BEST CHANCE IN THE AFTN WOULD PROBABLY BE IN THE WEST/SOUTHWEST CWA
WITH BETTER SHOT OF EARLIER CLEARING/WARMER TEMPERATURES. HUMID
CONDITIONS THAT HAVE DEVELOPED TODAY WILL CONTINUE THROUGH FRIDAY
WITH DWPNTS STAYING AT OR ABOVE 60 IN MANY AREAS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 431 AM EDT FRI JUN 21 2013
UPPER AIR PATTERN CONSISTS OF A 500 MB TROUGH OVER THE WESTERN U.S.
AND A SHORTWAVE OVER THE UPPER MISSISSIPPI RIVER VALLEY WITH A RIDGE
OVER THE UPPER GREAT LAKES 12Z SAT. THE TROUGH AND SHORTWAVE MOVE
THROUGH THE AREA THIS WEEKEND AND WILL BRING UNSETTLED WEATHER TO
THE AREA. THIS IS GOING TO BE HARD TO TIME ANY LITTLE WAVES THAT
MOVE THROUGH THE AREA. WITH A FRONT IN THE AREA...HARD TO TIME POPS
AND WILL CONTINUE WITH THE CHANCE POPS THAT WERE IN THERE. ONE THING
I DID DO THOUGH WAS RAISE HIGH TEMPERATURES A BIT FOR SAT AND
SUNDAY. 850 MB TEMPERATURES ALOFT GET CLOSE TO 20C AND MIXING THIS
DOWN TO THE SFC GIVES ME HIGHS NEAR 90 ON SUNDAY. WENT LOWER 80S ON
SATURDAY AND MID TO UPPER 80S ON SUNDAY. ANY SUNSHINE WILL HELP WARM
THE TEMPERATURES UP AND AGAIN DO NOT THINK BOTH DAYS WILL BE
WASHOUTS BY ANY MEANS. BROADBRUSHING CHANCE POPS LOOKS GOOD FOR BOTH
DAYS. OTHERWISE...NO MAJOR CHANGES TO THE GOING FORECAST. LOOKS
HUMID AND WARM AS WELL.
IN THE EXTENDED...GFS AND ECMWF SHOW A BROAD 500 MB RIDGE ACROSS THE
SOUTHERN AND EASTERN U.S. 12Z MON WITH A DEEP TROUGH ACROSS THE
WESTERN U.S. THERE IS ALSO A SHORTWAVE TROUGH MOVING THROUGH SOUTH
CENTRAL CANADA AT THAT TIME. THIS SHORTWAVE HELPS TO FLATTEN THE
RIDGE A BIT OVER THE AREA AND CONTINUE TO PUT THE AREA IN THE RING
OF FIRE CONVECTION SCENARIO ON THE EDGE OF THE RIDGE. ANY SHORTWAVE
THAT MOVES THROUGH HAS THE POTENTIAL TO KICK OFF SOME SHOWERS AND
THUNDERSTORMS. UPPER PATTERN THEN EVOLVES INTO A RIDGE ACROSS THE
ROCKIES ON THU WITH TROUGHING OVER THE UPPER GREAT LAKES THEN WITH
AREA STILL IN THE RING OF FIRE SCENARIO THEN. LOOKS PRETTY UNSETTLED
THROUGH THIS EXTENDED PERIOD ALONG WITH SOME WARMER WEATHER AND
ABOVE NORMAL TEMPERATURES AND HUMIDITY THIS FORECAST PERIOD. TRYING
TO TIME THE PERIODS OF CONVECTION WILL BE DIFFICULT AND DO NOT THINK
THE WHOLE TIME WILL BE A WASHOUT EITHER AS THERE WILL BE SOME BRIEF
DRY PERIODS IN THERE. BROADBRUSHING CHANCE POPS FOR THE PERIOD LOOKS
GOOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1212 AM EDT FRI JUN 21 2013
WILL BE A CHALLENGING FCST THRU THIS PERIOD DUE TO UNCERTAINTIES IN
CONVECTION AND LOW CLOUDS/FOG. INITIALLY...AS EXPECTED...MAIN AREAS
OF TSRA SO FAR TONIGHT HAVE BEEN SLIDING SE TO THE S OF THE AREA AS
CONVECTION FOLLOWS 850-300MB THICKNESS PATTERN. SHRA FARTHER N THAT
HAVE BEEN AFFECTING KIWD/KCMX/KSAW SHOULD DIMINISH FOR A WHILE. AT
KCMX...COOL EASTERLY UPSLOPE FLOW OFF LAKE SUPERIOR INTO HIGHER DWPT
AIR MASS OVER THE KEWEENAW HAS RESULTED IN LIFR CONDITIONS...AND
LIFR WILL LINGER THRU THE NIGHT UNDER CONTINUED LIGHT EASTERLY
WINDS. AT KSAW...WITH -SHRA DIMINISHING...FOG/MVFR CONDITIONS SHOULD
PREVAIL OVERNIGHT. NOT OUT OF THE QUESTION THAT CONDITIONS COULD
FALL TO IFR WITH FOG/STRATUS. DOWNSLOPE E/SE WINDS SHOULD ALLOW VFR
CONDITIONS OVERNIGHT AT KIWD THOUGH MVFR WILL OCCUR WITH ANY
SHRA/TSRA. LATER IN THE NIGHT...DISTURBANCE EMERGING FROM THE NRN
PLAINS SHOULD SUPPORT A MORE ORGANIZED CLUSTER OF SHRA/TSRA
SPREADING TOWARD THE AREA. GIVEN ARRIVAL DURING THE MORNING IN THE
USUAL DIURNAL MIN FOR CONVECTION...TSRA POTENTIAL SHOULD BE MORE
LIMITED. INCLUDED MVFR CONDITIONS WITH SHRA/VCTS AT KIWD...BUT JUST
SHRA AT KCMX/KSAW. AFTER A FEW HRS OF PCPN...CONDITIONS SHOULD BREAK
OUT TO VFR AT KIWD/KSAW...BUT MAY RETURN TO IFR UNDER CONTINUED COOL
UPSLOPE EASTERLY FLOW AT KCMX. EXPECT A BREAK OUT TO VFR AT KCMX IN
THE AFTN. ADDITIONAL CONVECTIVE DEVELOPMENT THIS AFTN/EVENING IS
UNCERTAIN. FOR NOW...WILL PLAN FOR A MORE LIKELY DRY SCENARIO IN THE
WAKE OF SHORTWAVE PASSING IN THE MORNING/EARLY AFTN. FOG MVFR
CONDITIONS MAY DEVELOP THIS EVENING AT KIWD/KSAW WHILE COOL EASTERLY
UPSLOPE FLOW ARGUES FOR A RETURN TO LIFR AT KCMX.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 431 PM EDT THU JUN 20 2013
FOG...AND ANY STRONGER STORMS /WITH WINDS AND/OR SMALL HAIL/ WILL BE
THE MAIN HAZARDS THROUGH THE WEEKEND. OTHERWISE WINDS SHOULD REMAIN
AT OR BELOW 25KTS.
A TROUGH OF ACROSS LAKE SUPERIOR WILL...DEEPEN FRIDAY NIGHT...AND
AGAIN SUNDAY THROUGH MONDAY. THIS WILL BE IN RESPONSE TO AN
ELONGATED AREA OF LOW PRESSURE STRETCHING FROM SOUTHWESTERN CANADA
THROUGH EASTERN COLORADO. EXPECT THE AREA OF LOW PRESSURE TO
CONSOLIDATE ACROSS THE CENTRAL PLAINS ON SATURDAY...BEFORE SHIFTING
INTO MANITOBA ON SUNDAY...AND EXITING EASTWARD THROUGH ONTARIO ON
MONDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLA
LONG TERM...07
AVIATION...ROLFSON
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1212 AM EDT FRI JUN 21 2013
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 431 PM EDT THU JUN 20 2013
UPPER AIR PATTERN FEATURES DEEP TROUGHING OVER NORTHWEST CONUS WITH
RIDGING DOWNSTREAM OVER NORTHERN PLAINS. SFC FRONT WITH DRIER AIR IS
WORKING ACROSS DAKOTAS WITH WEAK SFC LOW OVR NCNTRL SD BTWN KBIS AND
KABR. BASED ON SFC OBS AND VIS SATELLITE APPEARS WARM FRONT EXTENDS
FROM SFC LOW ACROSS CNTRL MN AND INTO NORTHWEST WI. NOT MUCH OF A
TEMP GRADIENT AT H85 BUT RIBBON OF HIGHER H85-H7 DWPNT ALONG WITH
H85 CONVERGENCE FROM NORTHERN MN ACROSS UPR MICHIGAN IS SERVING AS
FOCUS WAVE AFTER WAVE OF SCT SHRA/ISOLD TSRA. NO STRONG TSTM THOUGH
AS CAPE AVAILABLE OVR THE AREA IS BLO 1000 J/KG. DEEP LAYER SHEAR IS
MARGINAL AS WELL...MAYBE UP TO 30 KTS. STRONGEST CONVECTION TODAY
HAVE HAD LIGHTNING BUT HAVE REALLY SHOWN LITTLE TILT OWING TO THE
LIMITED INSTABILITY/SHEAR.
BASED ON WV LOOP/LIGHTNING AND RUC ANALYSIS...DOES SEEM THAT THERE
IS ONE WEAKER SHORTWAVE OVER NORTHWEST WI...ANOTHER NEAR THE DLH
AREA...AND A STRONGER WAVE LIFTING ENE ACROSS NORTHEAST ND. EXPECT
ISOLD-SCATTERED SHRA AND TSRA OVR CWA THROUGH EVENING...ESPECIALLY
NORTHERN HALF...AS THESE WAVES SLIDE THROUGH ALONG THE BOUNDARY AT
H85. OVERALL...LIMITED INSTABILITY SHOULD PRECLUDE STRONGER STORMS
THIS EVENING OVR MUCH OF CWA. EXCEPTION MAY BE IN FAR SW VCNTY OF
IWD AS MLCAPE BUILDING UP OVER 1000J/KG JUST TO SOUTHWEST OF WEST
CWA AND SWRLY STORM MOTION COULD RESULT IN STRONGER STORM WITH GUSTY
WINDS AND HAIL. THUS FAR NO REAL INDICATIONS OF THIS WITH UPSTREAM
STORMS BUT IT IS SOMETHING TO WATCH.
LATER TONIGHT...MAIN QUESTION IS WHAT WILL OCCUR WITH UPSTREAM
CONVECTION. IN A NUTSHELL...APPEARS THAT IF PRIMARY AREA OF
CONVECTIVE DEVELOPING THROUGH EARLY EVENING OCCURS ALONG AND EAST OF
SFC LOW...850-300MB THICKNESS/ORIENTATION OF HIGHEST MUCAPE/FORWARD
PROPAGATING CORFIDI VECTORS POINT TO MAIN TRACK OF SHRA/TSRA COMPLEX
OR BONIFIDE MCS MAINLY STAYING SOUTH OF CWA...WOULD BE CLOSE IN THE
SOUTHWEST CWA THOUGH. ON THE OTHER HAND...IF CONVECTION OVR
NORTHEAST ND CONTINUES TO DRIFT ACROSS RIDGE TOP IT COULD ADVECT
AND/OR SPUR ON ADDITIONAL SHRA/TSRA OVERNIGHT IN NORTHERN MN AND
BASED ON 850-300MB THICKNESSES...SHRA/TSRA WOULD TRACK INTO FAR
WESTERN UPR MICHIGAN 08Z-12Z. INCREASING SFC-ML CAPES AND 0-1KM
SHEAR UP TO 20 KTS AND BOW-LIKE APPEARANCE FROM VARIOUS HIGHER
RESOLUTION MODELS INDICATE IF THIS CONVECTION IMPACTS WESTERN CWA
THERE COULD BE STRONG WIND GUSTS. WITH ALL THE CLOUD COVER AND
POSSIBLE SHRA/TSRA WILL BE A WARM NIGHT WITH LOWS IN THE MID 50S
EAST AND STAYING ABOVE 60 DEGREES OVER THE WEST.
FOR FRIDAY...CONDITIONAL FORECAST FOR SURE. IF THE SHRA/TSRA ARE
AROUND IN THE MORNING...EXPECT A GENERAL LULL LATE MORNING INTO MOST
OF THE AFTN DUE TO THE SUBSIDENCE IN WAKE OF THE CONVECTION. MIXING
TO H9 WOULD SUPPORT HIGHS WELL INTO THE 70S IF NOT REACHING 80 WITH
ENOUGH SUNSHINE. AFTN INSTABILITY AND WARM FRONT/OUTFLOW IN THE VCNTY
COULD LEAD TO MORE DEVELOPING SHRA/TSRA MID-LATE AFTN. LOW CHANCE
POPS FOR ALL AREAS AFTER THE MAIN SHRA/TSRA CHANCES IN THE MORNING.
BEST CHANCE IN THE AFTN WOULD PROBABLY BE IN THE WEST/SOUTHWEST CWA
WITH BETTER SHOT OF EARLIER CLEARING/WARMER TEMPERATURES. HUMID
CONDITIONS THAT HAVE DEVELOPED TODAY WILL CONTINUE THROUGH FRIDAY
WITH DWPNTS STAYING AT OR ABOVE 60 IN MANY AREAS.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 431 PM EDT THU JUN 20 2013
FRI NIGHT...
AFTER THE EXPECTED AREA OF SHRA/TSRA EXITS THE ERN CWA FRI
EVENING... CONSENSUS OF MODELS SUGGEST PERHAPS A BREAK IN SHRA/TSRA
BY LATE FRI EVENING BEFORE MORE CONVECTION DEVELOPS OVER THE UPPER
MS VALLEY ALONG THE 850 MB WARM FRONT. THE FCST REFLECTS MODEL
TRENDS THAT KEEP THE FOCUS FOR CONVECTIVE DEVELOPMENT WITH THE
GREATEST INSTABILITY AND NOSE OF THE LLJ FARTHER SOUTH COMPARED TO
EARLIER RUNS.
SATURDAY AND SUNDAY...
AS THE MID LEVEL RIDGE BUILDS TO THE EAST...SW FLOW PATTERN WILL
ALLOW THE 850 MB WARM FRONT TO PUSH TO THE NORTH WITH WARM AND HUMID
AIR BECOMING ENTRENCHED OVER THE REGION. EVEN THOUGH THE MODELS HINT
AT POTENTIAL FOR A SHORTWAVE TROUGH MOVING OUT OF THE PLAINS TOWARD
NW ONTARIO SAT INTO SAT EVENING...UNCERTAINTY WITH THE
TIMING/POSITION OF THIS FEATURES AND THE IMPACT ON CONVECTIVE
DEVELOPMENT IS HIGH. WITH THE FOCUS FOR MOISTURE/LOW LEVEL THETA-E
ADVECTION SHIFTING FROM THE UPPER MS VALLEY TOWARD THE AREA...POPS
INCREASE INTO THE WRN CWA BY LATE AFTERNOON AND ACROSS UPPER
MICHIGAN SATURDAY NIGHT. WITH MLCAPE/MUCAPE VALUES INCREASING AT
LEAST INTO THE 1K-2K J/KG RANGE...THERE WILL BE A GREATER POTENTIAL
FOR STRONGER STORMS. THE MAIN HAZARD WILL BE HEAVY RAIN AS PWAT
VALUES CLIMB TO 1.5 TO 1.8 INCHES (150-180 PCT OR NORMAL).
WITH THE RIDGE BUILDING INTO THE AREA SUNDAY...CIN WILL INCREASE
WITH 700 MB TEMPS INTO THE 10C-12C RANGE. SO...TEMPS WILL CLIMB WELL
ABOVE NORMAL INTO THE 80S AND CONVECTION POTENTIAL WILL DECREASE.
HOWEVER...SHRA/TSRA MAY INCREASE AGAIN BY SUNDAY NIGHT AS A STRONGER
SHRTWV HELPS FLATTEN THE RIDGE AND BRINGS A WEAK SFC TROUGH INTO THE
REGION.
MON-THU...
THERE MAY BE DRIER PERIOD WITH A WEAK MID LEVEL AND SFC RIDGE INTO
THE AREA MON INTO TUE. HOWEVER...CONFIDENCE REMAINS LOW WITH THE
RETROGRADING RIDGE LEADING TO A MORE ZONAL PATTERN. AS THE RIDGE
BUILDS OVER THE WRN CONUS...A MORE NW FLOW PATTERN WILL STILL KEEP
POTENTIAL FOR SHRA/TSRA GOING. TEMPS SHOULD TRANSITION BACK TOWARD
MORE NORMAL VALUES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1212 AM EDT FRI JUN 21 2013
WILL BE A CHALLENGING FCST THRU THIS PERIOD DUE TO UNCERTAINTIES IN
CONVECTION AND LOW CLOUDS/FOG. INITIALLY...AS EXPECTED...MAIN AREAS
OF TSRA SO FAR TONIGHT HAVE BEEN SLIDING SE TO THE S OF THE AREA AS
CONVECTION FOLLOWS 850-300MB THICKNESS PATTERN. SHRA FARTHER N THAT
HAVE BEEN AFFECTING KIWD/KCMX/KSAW SHOULD DIMINISH FOR A WHILE. AT
KCMX...COOL EASTERLY UPSLOPE FLOW OFF LAKE SUPERIOR INTO HIGHER DWPT
AIR MASS OVER THE KEWEENAW HAS RESULTED IN LIFR CONDITIONS...AND
LIFR WILL LINGER THRU THE NIGHT UNDER CONTINUED LIGHT EASTERLY
WINDS. AT KSAW...WITH -SHRA DIMINISHING...FOG/MVFR CONDITIONS SHOULD
PREVAIL OVERNIGHT. NOT OUT OF THE QUESTION THAT CONDITIONS COULD
FALL TO IFR WITH FOG/STRATUS. DOWNSLOPE E/SE WINDS SHOULD ALLOW VFR
CONDITIONS OVERNIGHT AT KIWD THOUGH MVFR WILL OCCUR WITH ANY
SHRA/TSRA. LATER IN THE NIGHT...DISTURBANCE EMERGING FROM THE NRN
PLAINS SHOULD SUPPORT A MORE ORGANIZED CLUSTER OF SHRA/TSRA
SPREADING TOWARD THE AREA. GIVEN ARRIVAL DURING THE MORNING IN THE
USUAL DIURNAL MIN FOR CONVECTION...TSRA POTENTIAL SHOULD BE MORE
LIMITED. INCLUDED MVFR CONDITIONS WITH SHRA/VCTS AT KIWD...BUT JUST
SHRA AT KCMX/KSAW. AFTER A FEW HRS OF PCPN...CONDITIONS SHOULD BREAK
OUT TO VFR AT KIWD/KSAW...BUT MAY RETURN TO IFR UNDER CONTINUED COOL
UPSLOPE EASTERLY FLOW AT KCMX. EXPECT A BREAK OUT TO VFR AT KCMX IN
THE AFTN. ADDITIONAL CONVECTIVE DEVELOPMENT THIS AFTN/EVENING IS
UNCERTAIN. FOR NOW...WILL PLAN FOR A MORE LIKELY DRY SCENARIO IN THE
WAKE OF SHORTWAVE PASSING IN THE MORNING/EARLY AFTN. FOG MVFR
CONDITIONS MAY DEVELOP THIS EVENING AT KIWD/KSAW WHILE COOL EASTERLY
UPSLOPE FLOW ARGUES FOR A RETURN TO LIFR AT KCMX.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 431 PM EDT THU JUN 20 2013
FOG...AND ANY STRONGER STORMS /WITH WINDS AND/OR SMALL HAIL/ WILL BE
THE MAIN HAZARDS THROUGH THE WEEKEND. OTHERWISE WINDS SHOULD REMAIN
AT OR BELOW 25KTS.
A TROUGH OF ACROSS LAKE SUPERIOR WILL...DEEPEN FRIDAY NIGHT...AND
AGAIN SUNDAY THROUGH MONDAY. THIS WILL BE IN RESPONSE TO AN
ELONGATED AREA OF LOW PRESSURE STRETCHING FROM SOUTHWESTERN CANADA
THROUGH EASTERN COLORADO. EXPECT THE AREA OF LOW PRESSURE TO
CONSOLIDATE ACROSS THE CENTRAL PLAINS ON SATURDAY...BEFORE SHIFTING
INTO MANITOBA ON SUNDAY...AND EXITING EASTWARD THROUGH ONTARIO ON
MONDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLA
LONG TERM...JLB
AVIATION...ROLFSON
MARINE...JLB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
650 PM CDT SAT JUN 22 2013
.UPDATE...
ISSUED AT 645 PM CDT SAT JUN 22 2013
RECENT TRENDS WITH THE HRRR ALONG WITH HEAVY RAIN PROBABILITIES
FROM THE SREF AND THE OVERNIGHT QPF PLACEMENT FROM THE ECMWF HAS
PROMPTED A FLASH FLOOD WATCH THROUGH EARLY SUNDAY MORNING FOR A
GOOD PORTION OF CENTRAL AND SOUTHERN MN. RAINFALL AMOUNTS FROM THE
HRRR ARE IN THE 2 TO 3 INCH RANGE FROM MONTEVIDEO AND APPLETON ON
EAST THROUGH THE TWIN CITIES. THIS LINES UP WELL WITH THE SREF
PROBABILITIES OF 1 AND 2 INCH RAINS OVERNIGHT AND THE 12 HOUR QPF
FROM THE ECMWF. THIS IS ALSO AT THE NOSE OF THE RAP 925-850MB
MOISTURE TRANSPORT BETWEEN 06Z AND 12Z.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 334 PM CDT SAT JUN 22 2013
BIG THING TO START OFF THE SHORT TERM IS THE PRESENCE OF A
STRENGTHENING WARM FRONT ACROSS SRN MN...WHICH STRETCHES FROM
MARSHALL OVER TO FARIBAULT AND LA CROSSE AT 330 PM. SOUTH OF THE
BOUNDARY...SKIES HAVE CLEARED...WITH TEMPS RISING TO AROUND 90 TO
GO WITH MID/UPPER 60 DEWPOINTS. THIS BOUNDARY IS BEING REINFORCED
BY A COOL AND SHALLOW RIDGE OF HIGH PRESSURE THAT HAS COME DOWN FROM
THE NORTHEAST OFF OF LAKE SUPERIOR. FARTHER WEST...THERE IS A
DIFFUSE PRESSURE TROUGH/FRONT ORIENTED N/S ACROSS THE CENTRAL
DAKOTAS.
TONIGHT...THE WARM FRONT WILL TRY TO PUSH NORTH TO ABOUT THE I-94
CORRIDOR...BUT WILL CONTINUALLY BE STRUGGLING AGAINST LAKE SUPERIOR
HIGH. BY SUNDAY MORNING...THE TROUGH BACK OVER THE DAKOTAS WILL MOVE
INTO MN AND WILL BE BISECTING MN FROM THE SW CORNER UP TOWARD THE
INL AREA BY SUNDAY AFTERNOON.
FOR TONIGHT...LOTS OF UNCERTAINTY WITH HOW CONVECTION WILL EVOLVE.
ATMOSPHERE OVER MN/NRN WI REMAINS OVERTURNED AND WORKED OVER FROM
LAST NIGHTS CONVECTION...AS EVIDENCED BY MID LEVEL LAPSE RATES ON
THE SPC MESO ANALYSIS OF 5 TO 7 DEG C PER KM....THOUGH THEY HAVE
STARTED TO SHOWS SIGNS OF RECOVERING IN THE LAST COUPLE OF HOURS.
THESE WEAK LAPSE RATES WILL LIKELY KEEP THINGS FAIRLY BENIGN ACROSS
THE MPX AREA UNTIL CLOSER TO 00Z. AS 00Z APPROACHES...A 30-40KT LLJ
WILL BEGIN COMING UP OUT OF IA AND IMPINGING ON THE WARM FRONT
ACROSS MN...WHICH SHOULD REALLY START TO RAMP UP PRECIP CHANCES.
MAIN QUESTION THEN FOR TONIGHT BECOMES HOW FAR NORTH DOES THE WARM
FRONT AND NOSE OF THE LLJ GO. ONCE AGAIN...EXPECT THE NOSE OF THE
LLJ TO BE VERY ACTIVE...WITH WIDESPREAD TSRA THAT WILL HAVE THE
POTENTIAL TO TRAIN...WITH ANOTHER ROUND OF HEAVY RAIN AND FLASH
FLOODING BEING POSSIBLE TONIGHT. IN ADDITION TO THE HEAVY
RAIN...SHEAR WILL BE SUFFICIENT ENOUGH TO WARRANT A RISK OF SEVERE
WEATHER THROUGH THE NIGHT...WITH THE MAIN TREAT BEING WET MICRO/DOWN
BURSTS ONCE AGAIN. GOING WITH A BLEND OF THE ECMWF/GFS/NAM...THE
PART OF THE AREA THAT WOULD BE MOST AT RISK FOR SEEING THUNDERSTORMS
WOULD ESSENTIALLY BE THE HEART OF THE MPX CWA FROM SW MN...UP
THROUGH THE TWIN CITIES AND OVER INTO WRN WI.
UNFORTUNATELY...HI-RES MODELS ARE OF NO USE TONIGHT...AS EACH WRF
MEMBER HAS ITS OWN UNIQUE IDEA OF HOW THINGS WILL EVOLVE. AND THE
HRRR HAS SHOWN CONSIDERABLE VARIABILITY FROM RUN TO RUN. GIVEN ALL
OF THE UNCERTAINTY...CAN NOT PIN DOWN EXACTLY WHERE THE GREATEST
FLASH FLOOD EXISTS THROUGH TONIGHT...SO HAVE OPTED NOT TO ISSUE A
FLASH FLOOD WATCH. GREATEST THREAT OF COURSE WOULD BE ALONG/NORTH OF
THE WARM FRONT...WHEREVER IT DECIDES TO SETUP SHOP TONIGHT.
FOR SUNDAY...THE DAKOTAS BOUNDARY WILL BE DRIFTING INTO MN...WITH
DRIER AIR COMING IN BEHIND IT. THIS MAY ACTUALLY ALLOW FOR A DRY DAY
IN WRN MN...BUT ON THE OTHER SIDE OF THE CWA...THE LLJ WILL BE
INCREASING BY THE AFTERNOON...WITH THUNDERSTORMS EXPECTED TO AGAIN
EXPAND IN COVERAGE FROM SOUTH CENTRAL MN INTO WRN WI.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 334 PM CDT SAT JUN 22 2013
THUNDERSTORM ACTIVITY WILL LIKELY BE ONGOING AT THE START OF THE
LONG TERM PERIOD SUNDAY EVENING ACROSS WRN WI. WEST OF THE COLD
FRONT...DRIER AIR WILL FINALLY BRING CLEARING CONDITIONS AND A
RESPITE FROM REPEATED ROUNDS OF CONVECTION SUNDAY NIGHT AND
MONDAY.
RIDGING WILL BUILD OVER THE PLAINS MONDAY. 925 MB TEMPS MONDAY
WILL RISE TO BETWEEN +23 AND +25C...SO THINKING HIGHS IN THE UPPER
80S ARE LIKELY AND SEVERAL LOCATIONS OVER SWRN MN COULD REACH THE
LOWER 90S.
THE NOSE OF MID LEVEL RIDGING WILL BEGIN TO REACH SRN MN TUESDAY.
MODELS CONTINUE TO ADVERTISE ANOTHER DISTURBANCE SLIDING AROUND...
AND TO THE NORTH OF THIS RIDGING MONDAY NIGHT AND TUESDAY.
MAINTAINED MEDIUM POPS THROUGHOUT THIS TIME. FOLLOWING THE PASSAGE
OF THE ANY MORNING MCS/S...TUESDAY MAY TURN HOT AND HUMID PRIOR
TO COLD FRONTAL PASSAGE TUESDAY EVENING. NAM WOULD FAVOR HIGHS IN
THE LOW/MID 90S WITH PRONOUNCED THERMAL RIDGING. GFS/ECMWF ARE
SLIGHTLY COOLER ACROSS THE ERN CWA WITH MCS CLOUDINESS PERSISTING
INTO THE AFTERNOON HOURS.
A MUCH DRIER PERIOD WILL TAKE HOLD IN THE LATTER HALF OF THE LONG
TERM WITH RIDGING RETROGRADING BACK INTO THE WESTERN STATES AND A
ZONAL TO NORTHWEST FLOW RETURNING TO THE MIDWEST/GREAT LAKES.
THIS WILL BRING COOLER THAN NORMAL TEMPERATURES TO MUCH OF THE
EASTERN CONUS HEADING INTO THE HOLIDAY WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 645 PM CDT SAT JUN 22 2013
CONVECTION UNDERWAY EARLY THIS EVENING ACROSS PORTIONS OF
SOUTHERN MN AND ADJOINING AREAS OF WI ALONG A BOUNDARY. THIS
BOUNDARY WILL LIFT SLOWLY NORTHWARD TONIGHT WITH STORMS BECOMING
MORE WIDESPREAD. RECENT TRENDS FROM THE HRRR POINT TO EXTENSIVE
CONVECTION AFFECTING KAXN AND KRWF ON EASTWARD TO KMSP DURING THE LATE
EVENING AND OVERNIGHT HOURS. AS PER THE PAST TWO NIGHTS...LOW MVFR
OR IFR CEILINGS DEVELOPING IN THE WAKE OF THE CONVECTION ALONG
WITH BR. EXPECT CEILINGS TO IMPROVE TO VFR BY LATE MORNING AS MIXING
OCCURS WITH INCREASING S TO SW WINDS OF 12-15 KNOTS WITH GUSTS TO
25 KNOTS.
KMSP...
MAIN CONCERN OVERNIGHT IS WHEN THUNDERSTORMS SPREAD IN. THE MOST
CONCENTRATED STORMS ARE EXPECTED BETWEEN 07Z AND 11Z BUT COULD
START AS EARLY AS 05Z. LOW MVFR/IFR CEILINGS IN THE WAKE OF THE
STORMS INTO SUNDAY MORNING WITH IMPROVEMENT TO VFR BY 15Z. LIGHT
NE WINDS THIS EVENING BECOMING SE AFTER MIDNIGHT AND THEN MORE
SOUTHERLY BY LATE SUNDAY MORNING. SPEEDS INCREASING TO 10 TO 15
KNOTS ON SUNDAY. SCATTERED SHOWERS SUNDAY MORNING WITH
THUNDERSTORMS POSSIBLE SUNDAY AFTERNOON/EVENING.
/OUTLOOK FOR KMSP/
MON...VFR. WIND SE 5-10 KTS.
MON NIGHT...CHC TSRA. VFR OUTSIDE OF TSRA. WINDS SE 5-10 KTS.
TUE...CHC TSRA. VFR OUTSIDE OF TSRA. WINDS SSE 10-15 KTS.
WED...CHC TSRA. VFR OUTSIDE OF TSRA. WINDS S SHIFT TO NW 10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...FLASH FLOOD WATCH THROUGH SUNDAY MORNING FOR MNZ041-042-047>049-
051-054>062-064>069-073>076-082-083-091.
WI...NONE.
&&
$$
UPDATE...RAH
SHORT TERM...MPG
LONG TERM...BORGHOFF
AVIATION...RAH
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
346 PM CDT FRI JUN 21 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 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 127 PM CDT FRI JUN 21 2013
WINDS STARTING TO SETTLE BACK TO THE EAST IN THE WAKE OF LAST
NIGHTS SYSTEM. GOING OF THE H7 TEMP MESOANALYSIS...BELIEVE THE MPX
AREA IS CAPPED FOR ANY CONVECTION THIS AFTERNOON...INSTEAD WE ARE
WAITING ON THE GROWING AREA OF STORMS OVER SODAK FOR MORE TSRA
ACTIVITY. RELIED HEAVILY ON THE HRRR TO TIME THESE SODAK STORMS
ACROSS THE TERMINALS TONIGHT. AT THE MOMENT...IS LIKELY THEY MAY
SKIRT JUST TO THE SOUTH OF AXN/STC...SO HAVE NO TEMP GROUPS THERE.
AFTER THAT...HRRR IS INDICATING STORMS WILL CONTINUE TO FIRE ON
THE NOSE OF THE LLJ OVER SE SODAK AND CONTINUE TO TRACK EAST...SO
THERE IS THE POTENTIAL FOR RWF IN PARTICULAR TO SEE AT LEAST A
COUPLE OF ROUNDS OF STORMS TONIGHT. MVFR CIGS WILL LINGER ACROSS
WRN WI FOR THE NEXT COUPLE OF HOURS. SHOULD THEN SEE VFR CONDS
UNTIL NEXT ROUND OF STORMS MOVE IN...WITH CIGS EXPECTED TO BEHAVE
VERY SIMILAR TO HOW THEY DID OVERNIGHT INTO THIS PAST MORNING.
KMSP...HRRR HAS BEEN CONSISTENT WITH TRACKING ANOTHER STRONG TO
SEVERE LINE OF STORMS ACROSS MSP THIS EVENING...THOUGH A BIT
EARLIER TONIGHT...WITH THE 3Z-6Z PERIOD LOOKING LIKE THE MOST
LIKELY WINDOW FOR ANOTHER ROUND OF STORMS. HRRR IS SHOWING STORMS
CONTINUING TO FIRE THROUGH THE NIGHT WEST OF THIS FIRST LINE.
CURRENT THINKING IS THAT ADDITIONAL CONVECTION WILL BE MAINLY SOUTH
OF THE FIELD...BUT IF THIS ADDITIONAL ACTIVITY DOES GO FARTHER
NORTH THAN CURRENTLY INDICATED...THEN THERE COULD BE SIGNIFICANT
IMPACTS DUE TO CONVECTION FOR MUCH OF THE NIGHT INTO SAT MORNING.
BY SATURDAY AFTERNOON...MOIST UNSTABLE AIRMASS WILL LEAD TO THE
POTENTIAL FOR MORE DIURNALLY DRIVEN CONVECTION TO END THE TAF.
/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 FROM 9 PM CDT THIS EVENING THROUGH SATURDAY
AFTERNOON FOR MNZ054-056>060-062>070-073>078-082>085-
091>093.
WI...FLASH FLOOD WATCH FROM 9 PM CDT THIS EVENING THROUGH SATURDAY
AFTERNOON FOR WIZ023>028.
&&
$$
SHORT TERM...MPG
LONG TERM...JRB
AVIATION...MPG
HYDROLOGY...JRB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
127 PM CDT FRI JUN 21 2013
.UPDATE...
ISSUED AT 1142 AM CDT FRI JUN 21 2013
LARGE MCS FROM LAST NIGHT HAS NOW PUSHED INTO ERN WI AND NRN IL.
IN ITS WAKE...STRONG OUTFLOW BOUNDARY HAS DEVELOPED IN IOWA FROM
ROUGHLY THE QUAD CITIES BACK TO AROUND THE SIOUX CITY AREA. BASED
ON WIND FIELD...MAIN WARM FRONTAL BOUNDARY STRETCHES FROM SOUTH OF
CANBY SOUTHEAST TOWARD ST. JAMES AND ALBERT LEA.
WITH THE MORNING UPDATE...DID CUT BACK SIGNIFICANTLY ON POPS
THROUGH 00Z AS VERY FEW HI-RES CAMS SHOW ANY CONVECTION FORMING
DURING THE DAYLIGHT HOURS IN MN/WI. COUPLE OF REASONS FOR THIS
APPEARS TO BE THE FACT THAT THE ATMO IS PRETTY WORKED OVER AFTER
LAST NIGHT /AS SEEN WITH 12Z KMPX SOUNDING AND OUTFLOW BOUNDARY
DOWN IN IA/...ALONG WITH THE PRESENCE OF A CAPPING EML MOVING IN
FROM NEB...WITH THE 16Z SPC MESO ANALYSIS SHOWING THE +12C
ISOTHERM AT H7 CLEAR UP TO THE US-212 CORRIDOR IN MN. FOR THIS
REASON...STILL FEEL THAT THE MPX AREA WILL REMAIN HIGH AND DRY
THROUGH TODAY. HOWEVER...YOU CAN NOT COMPLETELY RULE OUT SOMETHING
FORMING ALONG WITH WARM FRONT LATER THIS AFTERNOON /AS MENTIONED
IN THE SPC DAY1 OUTLOOK/. IF SOMETHING WERE TO DEVELOP...THEN THE RISK FOR
LARGE HAIL...DAMAGING WINDS...AND POSSIBLY EVEN A TORNADO WILL
EXIST.
ONCE AGAIN HOWEVER...MORE ROBUST CONVECTION IN THE FORM OF AN MCS
IS EXPECTED TONIGHT. BASED ON THE HRRR AND 21.12 MPXWRF...THIS MCS
LOOKS LIKE IT WILL EVOLVE FROM THE LARGE THUNDERSTORM CURRENTLY
OVER THE BADLANDS OF SODAK. TO GO ALONG WITH THESE...THE 9Z
MEMBERS OF THE HOPWRF SHOW A SIMILAR TREND OCCURRING WITH
CONVECTION THIS AFTERNOON/EVENING AS WELL. LIKE LAST NIGHT...0-1KM
SHEAR WILL BE INCREASING AS NOCTURNAL LLJ INCREASES IN
STRENGTH...SO ANOTHER SEVERE BOW ECHO LOOKS LIKELY...JUST A MATTER
OF HOW FAR NORTH IT TRACKS.
GIVEN THE EXPECTATION OF ANOTHER MCS...MAY HAVE TO HOIST ANOTHER
FLASH FLOOD WATCH FOR TONIGHT ONCE A BETTER FEEL FOR WHERE THIS
NEXT MCS WILL TRACK CAN BE DETERMINED.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 422 AM CDT FRI JUN 21 2013
WE WILL KEEP THIS DISCUSSION SHORT AND SWEET. IT HAS BEEN A LONG
NIGHT. A MATURE MCS IS NOW IN THE EASTERN THIRD OF THE FORECAST
AREA AFTER TRACKING ACROSS THE ENTIRE STATE OF MN AND INTO WI
THROUGH THE OVERNIGHT HOURS. THERE IS LITTLE CHANGE IN THE LARGE-
SCALE FLOW REGIME ACROSS MN/WI OVER THE NEXT 24-36 HOURS.
SOUTHWESTERLY FLOW ALOFT WITH THE RIDGE OVERHEAD. 925MB-850MB
MOISTURE TRANSPORT EXPLODED LAST NIGHT AND WE SAW THE RESULT WITH
WIDESPREAD SEVERE WEATHER. THERE REALLY IS NOT MUCH DIFFERENCE
WITH THE UPCOMING SHORT TERM PATTERN. THERE IS DECENT CONSENSUS
AMONGST THE NAM/GFS/ECMWF WITH THE DEVELOPMENT OF ANOTHER
CONVECTIVE COMPLEX LATE IN THE AFTERNOON AND EVENING NEAR THE
MN/SD BORDER AND MARCHING THAT EAST WITH TIME. MODERATE TO HIGH
INSTABILITY VALUES WILL NOT BE A PROBLEM AS WE RELOAD TODAY AND
THE DEEP LAYER SHEAR WILL BE STRONG ENOUGH TO SUPPORT ORGANIZED
CONVECTION. SOME OF THE HIGHER RESOLUTION /CONVECTIVE ALLOWING
MODELS/ WE LOOK AT FOCUS MORE OF THE CONVECTION TO THE SOUTH IN
NE/IA. THIS WOULD BE FARTHER SOUTH THAN THE NAM/ECMWF/GFS/.
ADMITTEDLY SO...THESE THREE RUNS DO HAVE SOME DIFFERENCES. THE GFS
AND ECMWF ARE SIMILAR IN THE LOCATION OF CONVECTIVE INITIATION.
THE NAM IS FARTHER SOUTH BUT THE GFS AND ECMWF ARE SIMILAR.
HOWEVER...THE GFS IS FASTER. WE WILL HAVE TO PAY ATTENTION TO THE
OUTFLOW FROM THIS MORNING`S CONVECTION...THAT COULD BE A TRIGGER
TODAY. HOWEVER...THERE SHOULD BE AN EAST-WEST BOUNDARY...SO FLASH
FLOODING WILL AGAIN BE A MAJOR THREAT ALONG WITH THE HAIL AND
WIND...ESPECIALLY GIVEN THE SATURATED SOILS AFTER THIS MORNING. SO
IN SUMMARY...GET READY TO DO THIS ALL AGAIN TONIGHT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 422 AM CDT FRI JUN 21 2013
POTENT RIDGE OVER THE WRN CONUS WITH LONGWAVE TROUGHING OVER THE
WRN CONUS WILL PROMOTE PROGRESSIVE SWLY FLOW OVER THE UPR MISS
RIVER VALLEY REGION. DEEP MOISTURE...WITH PWATS NEARING 2
INCHES...WILL BE COMMON SAT THRU MON. SEVERAL SHTWV DISTURBANCES
FLYING WITHIN THE SW FLOW ALONG WITH A DEEPENING LOW PRES CENTER
OVER THE ERN DAKOTAS INTO WRN MN WITH THE WFO MPX CWFA IN THE WARM
SECTOR SPELLS ADDITIONAL ROUNDS OF HEAVY RAIN AND TSTMS THRU THE
WEEKEND. INSTABILITY REMAINS HIGH...WITH MLCAPES IN THE 3000-4000
J/KG RANGE...AND THE SAT PERIOD MAY START OUT WITH AN MCS AND/OR
CLUSTER OF TSTMS EXITING THE AREA. WIDESCALE LIFT...STEEP LAPSE
RATES AND ENHANCED BULK SHEAR WILL AGAIN PROMOTE THE RE-
DEVELOPMENT OF TSTMS BY SAT EVE INTO SAT NIGHT...SOME OF WHICH MAY
BE SEVERE WITH LARGE HAIL AND DMGG WINDS. A SIMILAR SITUATION WILL
THEN PRESENT ITSELF FOR SUN AS THE UPR TROUGH SHIFTS SLIGHTLY E...
HELPING DROP H5 HEIGHTS WHILE ENHANCING MID- AND UPR-LEVEL
JETTING. CONVECTIVE ACTIVITY MAY WELL AGAIN CONTINUE FROM LATE SAT
NIGHT INTO EARLY SUN MORNING...THEN AGAIN BECOME REINVIGORATED
FROM MIDDAY HEATING TO SPARK LATE AFTN AND EVE TSTMS FOR SUN. THE
DEEP MOISTURE REMAINING IN PLACE WILL AGAIN PROMOTE HEAVY RAIN AS
WELL. THIS LONGWAVE TROUGH WILL LIFT OUT GOING INTO MON...BUT WILL
GRADUALLY BE REPLACED BY ANOTHER UPPER LEVEL LOW CURRENTLY NEAR
ALASKA THAT WILL DROP ACROSS WRN CANADA INTO THE NRN PLAINS WED
THROUGH THU. THIS WILL THEN CREATE THE WRN RIDGE/ERN TROF PATTERN
THAT WILL SHOVE A LOW PRES CENTER NEWD ACRS MN INTO THE GRT LAKES
WED WITH THE UPR LOW TRAILING IT THRU THU. MID TO HIGH CHC RANGE
POPS WILL REMAIN IN THE FCST THRU THE MIDDLE OF NEXT WEEK...WITH
AGAIN CHCS FOR STRONG TSTMS ALONG WITH HVY RAIN. VERY LITTLE
CHANGE IN AIRMASS IS EXPECTED THRU THE MIDDLE OF NEXT WEEK...
WHICH MEANS HIGHS IN THE MID-UPR 80S AND LOWS IN THE MID 60S TO
LWR 70S. IN ADDITION...DEWPOINTS WILL REMAIN IN THE 60S TO LWR
70S WHICH MEANS HEAT INDEX VALUES UP INTO THE MID 90S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 127 PM CDT FRI JUN 21 2013
WINDS STARTING TO SETTLE BACK TO THE EAST IN THE WAKE OF LAST
NIGHTS SYSTEM. GOING OF THE H7 TEMP MESOANALYSIS...BELIEVE THE MPX
AREA IS CAPPED FOR ANY CONVECTION THIS AFTERNOON...INSTEAD WE ARE
WAITING ON THE GROWING AREA OF STORMS OVER SODAK FOR MORE TSRA
ACTIVITY. RELIED HEAVILY ON THE HRRR TO TIME THESE SODAK STORMS
ACROSS THE TERMINALS TONIGHT. AT THE MOMENT...IS LIKELY THEY MAY
SKIRT JUST TO THE SOUTH OF AXN/STC...SO HAVE NO TEMP GROUPS THERE.
AFTER THAT...HRRR IS INDICATING STORMS WILL CONTINUE TO FIRE ON
THE NOSE OF THE LLJ OVER SE SODAK AND CONTINUE TO TRACK EAST...SO
THERE IS THE POTENTIAL FOR RWF IN PARTICULAR TO SEE AT LEAST A
COUPLE OF ROUNDS OF STORMS TONIGHT. MVFR CIGS WILL LINGER ACROSS
WRN WI FOR THE NEXT COUPLE OF HOURS. SHOULD THEN SEE VFR CONDS
UNTIL NEXT ROUND OF STORMS MOVE IN...WITH CIGS EXPECTED TO BEHAVE
VERY SIMILAR TO HOW THEY DID OVERNIGHT INTO THIS PAST MORNING.
KMSP...HRRR HAS BEEN CONSISTENT WITH TRACKING ANOTHER STRONG TO
SEVERE LINE OF STORMS ACROSS MSP THIS EVENING...THOUGH A BIT
EARLIER TONIGHT...WITH THE 3Z-6Z PERIOD LOOKING LIKE THE MOST
LIKELY WINDOW FOR ANOTHER ROUND OF STORMS. HRRR IS SHOWING STORMS
CONTINUING TO FIRE THROUGH THE NIGHT WEST OF THIS FIRST LINE.
CURRENT THINKING IS THAT ADDITIONAL CONVECTION WILL BE MAINLY SOUTH
OF THE FIELD...BUT IF THIS ADDITIONAL ACTIVITY DOES GO FARTHER
NORTH THAN CURRENTLY INDICATED...THEN THERE COULD BE SIGNIFICANT
IMPACTS DUE TO CONVECTION FOR MUCH OF THE NIGHT INTO SAT MORNING.
BY SATURDAY AFTERNOON...MOIST UNSTABLE AIRMASS WILL LEAD TO THE
POTENTIAL FOR MORE DIURNALLY DRIVEN CONVECTION TO END THE TAF.
/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 422 AM CDT FRI JUN 21 2013
SEVERAL ROUNDS OF SHOWERS AND THUNDERSTORMS EXPECTED THROUGH THIS
WEEKEND ARE LIKELY TO PRODUCE HIGH RAINFALL TOTALS ACROSS THE
AREA...POTENTIALLY LEADING TO LOCALIZED FLOODING PROBLEMS. THE
PRIMARY TIME OF CONCERN WILL BE THROUGH LATE THIS MORNING...AND
AGAIN OVERNIGHT TONIGHT. THE OVERALL SYNOPTIC PATTERN IS SUCH
THAT A STRONG LOW PRESSURE AREA ACROSS THE WESTERN CONUS...AND A
HIGH PRESSURE AREA ACROSS THE EASTERN CONUS...ARE EXPECTED TO MOVE
VERY LITTLE OVER THE NEXT FEW DAYS...WHICH MEANS WE WILL REMAIN IN
A FAVORABLE ENVIRONMENT FOR THUNDERSTORMS DEVELOPMENT EACH
AFTERNOON/NIGHT. THIS SETUP HAS ALREADY BEGUN TO OPEN THE DOOR FOR
GULF MOISTURE TO BEGIN STREAMING INTO THE UPPER MIDWEST. SURFACE
DEW POINT TEMPERATURES WILL REACH 70 DEGREES WITH PRECIPITABLE
WATER VALUES BETWEEN 1.5 AND 2 INCHES. IN ADDITION...STRONG
MOISTURE TRANSPORT FROM THE GULF WILL AID IN DEVELOPING HEAVY
RAINFALL RATES. THIS MOIST AIR MASS WILL REMAIN OVER THE AREA FOR
THE NEXT SEVERAL DAYS...AND GIVEN THE ABUNDANT MOISTURE
AVAILABLE...EXTREMELY HEAVY RAINFALL RATES OF UP TO 3 INCHES PER
HOUR WILL BE POSSIBLE IN STRONG THUNDERSTORMS THAT TRAVERSE THE
AREA THROUGH THE WEEKEND. ANTECEDENT SOIL CONDITIONS ARE GENERALLY
MOIST GIVEN THE WET SPRING...WHICH ENHANCES THE POTENTIAL FOR
FLASH FLOODING. THROUGH NEXT WEEK...RAINFALL TOTALS COULD RANGE
FROM 3 TO 5 INCHES...WHICH WILL ALSO LEAD TO RISES ON MAIN STEM
RIVERS NEXT WEEK.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
UPDATE...MPG
SHORT TERM...CLF
LONG TERM...JPC
AVIATION...MPG
HYDROLOGY...JPC
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1143 AM CDT FRI JUN 21 2013
.UPDATE...
ISSUED AT 1142 AM CDT FRI JUN 21 2013
LARGE MCS FROM LAST NIGHT HAS NOW PUSHED INTO ERN WI AND NRN IL.
IN ITS WAKE...STRONG OUTFLOW BOUNDARY HAS DEVELOPED IN IOWA FROM
ROUGHLY THE QUAD CITIES BACK TO AROUND THE SIOUX CITY AREA. BASED
ON WIND FIELD...MAIN WARM FRONTAL BOUNDARY STRETCHES FROM SOUTH OF
CANBY SOUTHEAST TOWARD ST. JAMES AND ALBERT LEA.
WITH THE MORNING UPDATE...DID CUT BACK SIGNIFICANTLY ON POPS
THROUGH 00Z AS VERY FEW HI-RES CAMS SHOW ANY CONVECTION FORMING
DURING THE DAYLIGHT HOURS IN MN/WI. COUPLE OF REASONS FOR THIS
APPEARS TO BE THE FACT THAT THE ATMO IS PRETTY WORKED OVER AFTER
LAST NIGHT /AS SEEN WITH 12Z KMPX SOUNDING AND OUTFLOW BOUNDARY
DOWN IN IA/...ALONG WITH THE PRESENCE OF A CAPPING EML MOVING IN
FROM NEB...WITH THE 16Z SPC MESO ANALYSIS SHOWING THE +12C
ISOTHERM AT H7 CLEAR UP TO THE US-212 CORRIDOR IN MN. FOR THIS
REASON...STILL FEEL THAT THE MPX AREA WILL REMAIN HIGH AND DRY
THROUGH TODAY. HOWEVER...YOU CAN NOT COMPLETELY RULE OUT SOMETHING
FORMING ALONG WITH WARM FRONT LATER THIS AFTERNOON /AS MENTIONED
IN THE SPC DAY1 OUTLOOK/. IF SOMETHING WERE TO DEVELOP...THEN THE RISK FOR
LARGE HAIL...DAMAGING WINDS...AND POSSIBLY EVEN A TORNADO WILL
EXIST.
ONCE AGAIN HOWEVER...MORE ROBUST CONVECTION IN THE FORM OF AN MCS
IS EXPECTED TONIGHT. BASED ON THE HRRR AND 21.12 MPXWRF...THIS MCS
LOOKS LIKE IT WILL EVOLVE FROM THE LARGE THUNDERSTORM CURRENTLY
OVER THE BADLANDS OF SODAK. TO GO ALONG WITH THESE...THE 9Z
MEMBERS OF THE HOPWRF SHOW A SIMILAR TREND OCCURRING WITH
CONVECTION THIS AFTERNOON/EVENING AS WELL. LIKE LAST NIGHT...0-1KM
SHEAR WILL BE INCREASING AS NOCTURNAL LLJ INCREASES IN
STRENGTH...SO ANOTHER SEVERE BOW ECHO LOOKS LIKELY...JUST A MATTER
OF HOW FAR NORTH IT TRACKS.
GIVEN THE EXPECTATION OF ANOTHER MCS...MAY HAVE TO HOIST ANOTHER
FLASH FLOOD WATCH FOR TONIGHT ONCE A BETTER FEEL FOR WHERE THIS
NEXT MCS WILL TRACK CAN BE DETERMINED.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 422 AM CDT FRI JUN 21 2013
WE WILL KEEP THIS DISCUSSION SHORT AND SWEET. IT HAS BEEN A LONG
NIGHT. A MATURE MCS IS NOW IN THE EASTERN THIRD OF THE FORECAST
AREA AFTER TRACKING ACROSS THE ENTIRE STATE OF MN AND INTO WI
THROUGH THE OVERNIGHT HOURS. THERE IS LITTLE CHANGE IN THE LARGE-
SCALE FLOW REGIME ACROSS MN/WI OVER THE NEXT 24-36 HOURS.
SOUTHWESTERLY FLOW ALOFT WITH THE RIDGE OVERHEAD. 925MB-850MB
MOISTURE TRANSPORT EXPLODED LAST NIGHT AND WE SAW THE RESULT WITH
WIDESPREAD SEVERE WEATHER. THERE REALLY IS NOT MUCH DIFFERENCE
WITH THE UPCOMING SHORT TERM PATTERN. THERE IS DECENT CONSENSUS
AMONGST THE NAM/GFS/ECMWF WITH THE DEVELOPMENT OF ANOTHER
CONVECTIVE COMPLEX LATE IN THE AFTERNOON AND EVENING NEAR THE
MN/SD BORDER AND MARCHING THAT EAST WITH TIME. MODERATE TO HIGH
INSTABILITY VALUES WILL NOT BE A PROBLEM AS WE RELOAD TODAY AND
THE DEEP LAYER SHEAR WILL BE STRONG ENOUGH TO SUPPORT ORGANIZED
CONVECTION. SOME OF THE HIGHER RESOLUTION /CONVECTIVE ALLOWING
MODELS/ WE LOOK AT FOCUS MORE OF THE CONVECTION TO THE SOUTH IN
NE/IA. THIS WOULD BE FARTHER SOUTH THAN THE NAM/ECMWF/GFS/.
ADMITTEDLY SO...THESE THREE RUNS DO HAVE SOME DIFFERENCES. THE GFS
AND ECMWF ARE SIMILAR IN THE LOCATION OF CONVECTIVE INITIATION.
THE NAM IS FARTHER SOUTH BUT THE GFS AND ECMWF ARE SIMILAR.
HOWEVER...THE GFS IS FASTER. WE WILL HAVE TO PAY ATTENTION TO THE
OUTFLOW FROM THIS MORNING`S CONVECTION...THAT COULD BE A TRIGGER
TODAY. HOWEVER...THERE SHOULD BE AN EAST-WEST BOUNDARY...SO FLASH
FLOODING WILL AGAIN BE A MAJOR THREAT ALONG WITH THE HAIL AND
WIND...ESPECIALLY GIVEN THE SATURATED SOILS AFTER THIS MORNING. SO
IN SUMMARY...GET READY TO DO THIS ALL AGAIN TONIGHT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 422 AM CDT FRI JUN 21 2013
POTENT RIDGE OVER THE WRN CONUS WITH LONGWAVE TROUGHING OVER THE
WRN CONUS WILL PROMOTE PROGRESSIVE SWLY FLOW OVER THE UPR MISS
RIVER VALLEY REGION. DEEP MOISTURE...WITH PWATS NEARING 2
INCHES...WILL BE COMMON SAT THRU MON. SEVERAL SHTWV DISTURBANCES
FLYING WITHIN THE SW FLOW ALONG WITH A DEEPENING LOW PRES CENTER
OVER THE ERN DAKOTAS INTO WRN MN WITH THE WFO MPX CWFA IN THE WARM
SECTOR SPELLS ADDITIONAL ROUNDS OF HEAVY RAIN AND TSTMS THRU THE
WEEKEND. INSTABILITY REMAINS HIGH...WITH MLCAPES IN THE 3000-4000
J/KG RANGE...AND THE SAT PERIOD MAY START OUT WITH AN MCS AND/OR
CLUSTER OF TSTMS EXITING THE AREA. WIDESCALE LIFT...STEEP LAPSE
RATES AND ENHANCED BULK SHEAR WILL AGAIN PROMOTE THE RE-
DEVELOPMENT OF TSTMS BY SAT EVE INTO SAT NIGHT...SOME OF WHICH MAY
BE SEVERE WITH LARGE HAIL AND DMGG WINDS. A SIMILAR SITUATION WILL
THEN PRESENT ITSELF FOR SUN AS THE UPR TROUGH SHIFTS SLIGHTLY E...
HELPING DROP H5 HEIGHTS WHILE ENHANCING MID- AND UPR-LEVEL
JETTING. CONVECTIVE ACTIVITY MAY WELL AGAIN CONTINUE FROM LATE SAT
NIGHT INTO EARLY SUN MORNING...THEN AGAIN BECOME REINVIGORATED
FROM MIDDAY HEATING TO SPARK LATE AFTN AND EVE TSTMS FOR SUN. THE
DEEP MOISTURE REMAINING IN PLACE WILL AGAIN PROMOTE HEAVY RAIN AS
WELL. THIS LONGWAVE TROUGH WILL LIFT OUT GOING INTO MON...BUT WILL
GRADUALLY BE REPLACED BY ANOTHER UPPER LEVEL LOW CURRENTLY NEAR
ALASKA THAT WILL DROP ACROSS WRN CANADA INTO THE NRN PLAINS WED
THROUGH THU. THIS WILL THEN CREATE THE WRN RIDGE/ERN TROF PATTERN
THAT WILL SHOVE A LOW PRES CENTER NEWD ACRS MN INTO THE GRT LAKES
WED WITH THE UPR LOW TRAILING IT THRU THU. MID TO HIGH CHC RANGE
POPS WILL REMAIN IN THE FCST THRU THE MIDDLE OF NEXT WEEK...WITH
AGAIN CHCS FOR STRONG TSTMS ALONG WITH HVY RAIN. VERY LITTLE
CHANGE IN AIRMASS IS EXPECTED THRU THE MIDDLE OF NEXT WEEK...
WHICH MEANS HIGHS IN THE MID-UPR 80S AND LOWS IN THE MID 60S TO
LWR 70S. IN ADDITION...DEWPOINTS WILL REMAIN IN THE 60S TO LWR
70S WHICH MEANS HEAT INDEX VALUES UP INTO THE MID 90S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 727 AM CDT FRI JUN 21 2013
BRIEF REPRIVE FROM THE THUNDERSTORMS LATE THIS MORNING AND
AFTERNOON...BUT INSTABILITY WILL BUILD THIS AFTERNOON AND SET THE
STAGE FOR ANOTHER ROUND OF THUNDERSTORMS THIS EVENING. STRONG WIND
AND HEAVY RAIN WILL BE A THREAT AT ALL TAF SITES FROM ABOUT 23Z
UNTIL 09-10Z.
KMSP...
VFR EXPECTED TODAY...BUT THUNDERSTORM CHANCES INCREASE LATE THIS
AFTERNOON. THE EVENT TODAY...SHOULD BE A LITTLE EARLIER WHEN
COMPARED TO THE TIMING OF LAST NIGHT`S STORMS.
/OUTLOOK FOR KMSP/
SAT...TSRA LIKELY. VFR OUTSIDE OF TSRA. WINDS SE 10 KTS
SUN...TSRA LIKELY. VFR OUTSIDE OF TSRA. WINDS SSW 10-15 KTS.
MON...CHC TSRA. VFR OUTSIDE OF TSRA. WINDS S 5-10KTS.
&&
.HYDROLOGY...
ISSUED AT 422 AM CDT FRI JUN 21 2013
SEVERAL ROUNDS OF SHOWERS AND THUNDERSTORMS EXPECTED THROUGH THIS
WEEKEND ARE LIKELY TO PRODUCE HIGH RAINFALL TOTALS ACROSS THE
AREA...POTENTIALLY LEADING TO LOCALIZED FLOODING PROBLEMS. THE
PRIMARY TIME OF CONCERN WILL BE THROUGH LATE THIS MORNING...AND
AGAIN OVERNIGHT TONIGHT. THE OVERALL SYNOPTIC PATTERN IS SUCH
THAT A STRONG LOW PRESSURE AREA ACROSS THE WESTERN CONUS...AND A
HIGH PRESSURE AREA ACROSS THE EASTERN CONUS...ARE EXPECTED TO MOVE
VERY LITTLE OVER THE NEXT FEW DAYS...WHICH MEANS WE WILL REMAIN IN
A FAVORABLE ENVIRONMENT FOR THUNDERSTORMS DEVELOPMENT EACH
AFTERNOON/NIGHT. THIS SETUP HAS ALREADY BEGUN TO OPEN THE DOOR FOR
GULF MOISTURE TO BEGIN STREAMING INTO THE UPPER MIDWEST. SURFACE
DEW POINT TEMPERATURES WILL REACH 70 DEGREES WITH PRECIPITABLE
WATER VALUES BETWEEN 1.5 AND 2 INCHES. IN ADDITION...STRONG
MOISTURE TRANSPORT FROM THE GULF WILL AID IN DEVELOPING HEAVY
RAINFALL RATES. THIS MOIST AIR MASS WILL REMAIN OVER THE AREA FOR
THE NEXT SEVERAL DAYS...AND GIVEN THE ABUNDANT MOISTURE
AVAILABLE...EXTREMELY HEAVY RAINFALL RATES OF UP TO 3 INCHES PER
HOUR WILL BE POSSIBLE IN STRONG THUNDERSTORMS THAT TRAVERSE THE
AREA THROUGH THE WEEKEND. ANTECEDENT SOIL CONDITIONS ARE GENERALLY
MOIST GIVEN THE WET SPRING...WHICH ENHANCES THE POTENTIAL FOR
FLASH FLOODING. THROUGH NEXT WEEK...RAINFALL TOTALS COULD RANGE
FROM 3 TO 5 INCHES...WHICH WILL ALSO LEAD TO RISES ON MAIN STEM
RIVERS NEXT WEEK.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
UPDATE...MPG
SHORT TERM...CLF
LONG TERM...JPC
AVIATION...CLF
HYDROLOGY...JPC
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
602 PM CDT FRI JUN 21 2013
.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 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 556 PM CDT FRI JUN 21 2013
THE STRONG MIDLEVEL RIDGE WILL CONTINUE TO CONTROL THE WEATHER
PATTERN THROUGH SATURDAY NIGHT. INSTABILITY WILL BE PLENTIFUL
TOMORROW AFTERNOON...BUT COVERAGE SHOULD ONCE AGAIN REMAIN
ISOLATED SINCE ANY LARGE-SCALE FORCING MECHANISM FOR ASCENT SHOULD
BE LACKING. THEREFORE...HAVE CONTINUED TO LEAVE ANY MENTION OF TS
0R SHRA OUT OF TAFS FOR NOW. DIURNAL CU SHOULD DEVELOP WITH BASES
AROUND 5000 FEET TOMORROW AROUND MIDDAY WITH WINDS THROUGHOUT THE
VALID TAF PERIOD REMAINING OUT OF THE SOUTH.
SPECIFICS FOR KSTL...
THE STRONG MIDLEVEL RIDGE WILL CONTINUE TO CONTROL THE WEATHER
PATTERN THROUGH SATURDAY NIGHT FOR LAMBERT FIELD. INSTABILITY WILL BE
PLENTIFUL TOMORROW AFTERNOON...BUT COVERAGE OF ANY STORMS WHICH
WOULD DEVELOP SHOULD ONCE AGAIN REMAIN ISOLATED SINCE ANY LARGE-
SCALE FORCING MECHANISM FOR ASCENT SHOULD BE LACKING.
THEREFORE...HAVE CONTINUED TO LEAVE ANY MENTION OF TS 0R SHRA OUT
OF TAF FOR NOW. DIURNAL CU SHOULD DEVELOP WITH BASES AROUND 5000
FEET TOMORROW AROUND MIDDAY WITH WINDS THROUGHOUT THE VALID TAF
PERIOD REMAINING OUT OF THE SOUTH.
GOSSELIN
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
325 PM CDT FRI JUN 21 2013
.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 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1216 PM CDT FRI JUN 21 2013
VFR CONDITIONS ARE EXPECTED TO DOMINATE THROUGH THE PERIOD WITH DIURNAL
CU AND SCATTERED MID CLOUDS AT NIGHT. A TYPICAL SUMMERTIME WARM
MOIST AND UNSTABLE AIR MASS IS PRESENT ACROSS THE AREA WHICH MEANS
AN ISOLATED THUNDERSTORM COULD DEVELOP JUST ABOUT ANYWHERE THIS
AFTERNOON UNTIL SUNSET. BEST INDICATIONS AT THIS TIME ARE THAT NE
MISSOURI INTO WEST CENTRAL IL MAY HAVE SLIGHTLY BETTER
PROBABILITIES. THE THREAT HOWEVER AT ANY TAF SITE IS TOO LOW TO
MENTION AT THIS TIME.
SPECIFICS FOR KSTL...
VFR CONDITIONS ARE EXPECTED TO DOMINATE THROUGH THE PERIOD WITH DIURNAL
CU AND SCATTERED MID CLOUDS AT NIGHT. A TYPICAL SUMMERTIME WARM
MOIST AND UNSTABLE AIR MASS IS PRESENT ACROSS THE AREA WHICH MEANS
AN ISOLATED THUNDERSTORM COULD DEVELOP JUST ABOUT ANYWHERE...THE
THREAT HOWEVER IS TOO LOW TO MENTION AT THIS TIME.
GLASS
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
1004 PM MDT Sat Jun 22 2013
.UPDATE...
The forecast area remains under the broad cyclonic circulation aloft
around an upper low centered over AB/SK, with one of several
shortwaves rotating around the larger low lifting east across
south-central MT and WY this evening. Instability from the
relatively cold pool of air aloft and cyclonic flow produced
widely scattered showers and weak thunderstorms across much of
the area this afternoon and evening, and this activity will
continue to decrease through the remainder of this evening.
Clearing skies and relatively light winds are expected overnight
with low temps in the 40s across most of the area. The Gallatin
valley received a quick period of wetting rain late in the evening
and clearing skies and light winds may lead to some patchy fog
development there, however with only about 7hrs of darkness this
time of year, am not expecting fog to be particularly dense or
widespread there. Hoenisch
&&
.AVIATION...
Updated 0405Z.
Scattered showers and thunderstorms will persist into the night as a
weak disturbance aloft moves through central Montana. The airmass
will not be as unstable Sunday although weak instability will
develop again during the afternoon,so isolated showers or
thunderstorms are possible. VFR conditions will prevail through the
next 24 hours.
&&
.PREV DISCUSSION...
/ISSUED 527 PM MDT Sat Jun 22 2013/
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
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 45 75 51 78 / 20 10 10 30
CTB 44 73 49 73 / 20 20 20 40
HLN 45 77 52 78 / 20 10 10 30
BZN 40 76 46 80 / 30 10 10 30
WEY 31 68 36 70 / 10 10 10 30
DLN 39 74 47 74 / 20 10 10 30
HVR 48 77 53 81 / 30 20 10 30
LWT 43 72 48 78 / 40 10 10 30
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
weather.gov/greatfalls
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
923 PM MDT Sat Jun 22 2013
.UPDATE...
The forecast area remains under the broad cyclonic circulation aloft
around an upper low centered over AB/SK, with one of several
shortwaves rotating around the larger low lifting east across
south-central MT and WY this evening. Instability from the
relatively cold pool of air aloft and cyclonic flow produced
widely scattered showers and weak thunderstorms across much of
the area this afternoon and evening, and this activity will
continue to decrease through the remainder of this evening.
Clearing skies and relatively light winds are expected overnight
with low temps in the 40s across most of the area. The Gallatin
valley received a quick period of wetting rain late in the evening
and clearing skies and light winds may lead to some patchy fog
development there, however with only about 7hrs of darkness this
time of year, am not expecting fog to be particularly dense or
widespread there. Hoenisch
&&
.AVIATION...
Updated 2326Z.
Scattered showers and thunderstorms will continue into the early
evening but the upper level low pressure system will move east
tonight and the airmass will stabilize. Weak instability will
develop again Sunday afternoon although only isolated showers or
thunderstorms are expected. VFR conditions will prevail through the
next 24 hours.
&&
.PREV DISCUSSION...
/ISSUED 527 PM MDT Sat Jun 22 2013/
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
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 45 75 51 78 / 20 10 10 30
CTB 44 73 49 73 / 20 20 20 40
HLN 45 77 52 78 / 20 10 10 30
BZN 40 76 46 80 / 30 10 10 30
WEY 31 68 36 70 / 10 10 10 30
DLN 39 74 47 74 / 20 10 10 30
HVR 48 77 53 81 / 30 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
527 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 2326Z.
Scattered showers and thunderstorms will continue into the early
evening but the upper level low pressure system will move east
tonight and the airmass will stabilize. Weak instability will
develop again Sunday afternoon although only isolated showers or
thunderstorms are expected. VFR conditions will prevail through the
next 24 hours.
&&
.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.
&&
$$
weather.gov/greatfalls
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
930 AM MDT FRI JUN 21 2013
.UPDATE...
AREA OF SEVERE THUNDERSTORMS THAT WAS OVER SE MT THIS MORNING HAS
MOVED INTO THE DAKOTAS. RECEIVED REPORTS OF GOLF BALL SIZED HAIL
AND FUNNEL CLOUDS FROM THE STORMS EARLIER THIS MORNING. MORE
CONVECTION WAS MOVING INTO THIS AREA FROM NE WY ON RADAR.
SHORTWAVES AND ISENTROPIC LIFT WILL PROVIDE LIFT TO SE MT...AND
MID LEVEL LAPSE RATES WERE UNSTABLE. WHILE THE HRRR MOVES
PRECIPITATION OUT OF THIS AREA THIS MORNING AND DOES NOT
REGENERATE IT...PREFER THE SSEO WHICH DOES REDEVELOP CONVECTION
OVER THIS AREA BY THIS EVENING. OTHER CONVECTION WILL DEVELOP
ACROSS THE REGION UNDER THE ACTIVE SW FLOW ASSOCIATED WITH THE
UPPER LOW AND IN THE RIGHT ENTRANCE REGION OF AN UPPER JET.
AIRMASS ACROSS THE AREA WILL BE UNSTABLE WITH GOOD SHEAR. NOTED
INVERTED-V SOUNDINGS FROM KMLS W AND HAVE ADDED MENTION OF SMALL
HAIL AND GUSTY WINDS TO THE FORECAST. WILL CONTINUE THE SEVERE
WORDING IN THE SE. OTHERWISE...LOWERED DEWPOINTS A BIT TODAY BASED
ON CURRENT AND EXPECTED TRENDS. HIGH TEMPERATURES IN THE 60S AND
70S WERE ON TRACK PER EXPECTED MIXING. ARTHUR
&&
.SHORT TERM...VALID FOR TDY AND SAT...
SEVERAL OPPORTUNITIES FOR SHOWERS AND STORMS WILL EXIST DURING THE
NEXT 36 HOURS AS THE UPPER-LEVEL TROUGH CENTERED OVER ID AT 09 UTC
HEADS EAST. WHILE THE RESERVOIR OF STRONGEST INSTABILITY WILL STAY
ANCHORED DOWNSTREAM IN THE DAKOTAS...ENOUGH INGREDIENTS WILL EXIST
FOR SOME RISK OF SEVERE STORMS ACROSS PARTS OF OUR AREA TOO.
EARLY THIS MORNING...ELEVATED CONVECTION FED ON A 30+ KT LOW-LEVEL
JET HAS BEEN FORMING EAST OF BILLINGS SINCE ABOUT 06 UTC. INFRARED
SATELLITE IMAGES SUGGEST ANOTHER SUBTLE SHORT WAVE IMPULSE LOCATED
OVER CENTRAL AND NORTHEAST WY WILL MOVE INTO SOUTHEASTERN MT BY 12
UTC. THAT LENDS CREDENCE TO THE LAST SEVERAL HRRR RUNS AND SEVERAL
OTHER HIGH-RESOLUTION...CONVECTION-ALLOWING MODEL SIMULATIONS FROM
00 UTC IN SHOWING ROBUST STORMS DEVELOPING BY MORNING FROM BROADUS
AND EKALAKA TOWARD BAKER. FORECAST SOUNDINGS AND RAP ANALYSES SHOW
MUCAPE ON THE ORDER OF 1000 J/KG...MID LEVEL LAPSE RATES OF 7 C/KM
OR BETTER...AND EFFECTIVE SHEAR OF 60 KT IN SOUTHEASTERN MT DURING
THE MORNING. THUS...SOME SEVERE HAIL IS POSSIBLE...AND WE ACTUALLY
DECIDED TO MENTION THE RISK OF SEVERE STORMS EXPLICITLY WITHIN THE
FORECAST DURING THE MORNING AT BROADUS...BAKER...AND EKALAKA.
LATER TODAY...WE KEPT THE MENTION OF SEVERE STORMS IN SOUTHEASTERN
MT...AND EXPANDED IT BACK WEST AS FAR AS SHERIDAN AND LODGE GRASS.
THE WESTWARD EXTENSION OF THE SEVERE RISK WAS DONE LARGELY TO GIVE
DUE RESPECT TO CALIBRATED SEVERE THUNDERSTORM PROBABILITIES OFF OF
THE 21 UTC SREF...WHICH ARE FOCUSED IN THE SHERIDAN AREA BY THE 21
TO 00 UTC TIME FRAME. WE HAVE TO ADMIT THOUGH THAT CONFIDENCE WITH
THIS EVENT REMAINS BELOW-NORMAL...AND EARLY-DAY CONVECTION WILL BE
A PLAYER IN HOW THINGS EVOLVE LATER TOO. IF IT IS PERSISTENT...THE
BOUNDARY LAYER MAY NOT DESTABILIZE ENOUGH FOR SURFACE-BASED STORMS
BY LATE AFTERNOON. ON THE OTHER HAND...ENOUGH ELEVATED INSTABILITY
EXISTS TO SUPPORT SEVERE HAIL EVEN IF CONVECTION JUST CONTINUES TO
REGENERATE OVER SOUTHEASTERN MT THROUGH THE DAY. FINALLY...WE ALSO
INCREASED POPS OVER SOUTH CENTRAL MT FROM LIVINGSTON TO BIG TIMBER
AND HARLOWTON THIS AFTERNOON TOO WHERE A DIFFERENT WAVE WILL ALLOW
AT LEAST WEAK AND SCATTERED SHOWERS AND STORMS TO FORM.
TONIGHT...ONCE EVENING CONVECTION WINDS DOWN AND/OR MOVES OFF INTO
THE DAKOTAS...WE MIGHT HAVE A BIT OF A BREAK IN PRECIPITATION. THE
00 UTC ECMWF SUGGESTS ANOTHER WEAK SHORT WAVE TROUGH WILL GENERATE
MORE SHOWERS OR STORMS OVER SOUTHEASTERN MT TOWARD DAYBREAK THOUGH
AND THAT IS A GOOD EXAMPLE OF WHY CHANCE POPS REMAIN NECESSARY FOR
MOST AREAS IN THE 06 TO 12 UTC TIME FRAME.
SAT...THE 500-HPA TROUGH AXIS IS EXPECTED TO SWEEP ACROSS THE AREA
DURING THE AFTERNOON AND EVENING. STRONG QG-FORCING CONCOMITANT TO
THAT TROUGH AND INSTABILITY AHEAD OF THE 500-HPA COLD POOL WILL BE
SUFFICIENT TO GENERATE A HEALTHY BATCH OF CONVECTION. WE INCREASED
POPS INTO THE CATEGORICAL /80 PERCENT/ RANGE ALONG AND EAST OF THE
BILLINGS TO SHERIDAN LINE TO REFLECT THE LIKELIHOOD FOR AT LEAST A
PERIOD OF STORMS AHEAD OF THE TROUGH. THAT MOVE HAS STRONG SUPPORT
FROM THE 00 UTC MULTI-MODEL CONSENSUS. WE WILL ACTUALLY HAVE A LOW
RISK OF SEVERE STORMS AGAIN TOO...ESPECIALLY IF STORMS ARE ABLE TO
GET FAR ENOUGH AHEAD OF THE MID-LEVEL TROUGH AXIS...WHERE THEY MAY
HAVE ACCESS TO STRONGER EFFECTIVE SHEAR. SCHULTZ
.LONG TERM...VALID FOR SUN...MON...TUE...WED...THU...
THE EARLY PART OF THE EXTENDED FORECAST LOOKS UNSETTLED WITH A
DRYING AND WARMING TREND FROM WEDNESDAY ONWARD. THE BEST CHANCE OF
SHOWERS AND THUNDERSTORMS WILL BE MONDAY AND TUESDAY AS SOUTHWEST
FLOW OPENS UP AGAIN AND PROVIDES SEVERAL SHORTWAVES AND DEEPENING
MOISTURE. RAISED POPS FOR TUESDAY AS MODELS HAVE SLOWED DOWN A BIT
ON BUILDING THE RIDGE NOW UNTIL WEDNESDAY.
MODELS WERE CONSISTENT IN BUILDING A STRONG RIDGE INTO THE
NORTHERN ROCKIES WEDNESDAY INTO FRIDAY. THE GFS ACTUALLY HAS A
594DM HEIGHT LINE WORKING INTO SOUTHWEST MONTANA FRIDAY. THAT
WOULD LEAD TO A WARM AND MAINLY DRY FORECAST. WILL HAVE TO WATCH
FOR RIDGE RIDING SHORTWAVES FOR ISOLATED CONVECTION...BUT AT THIS
TIME THE MODELS WERE DRY WITH THE MID LEVEL FLOW. TWH
&&
.AVIATION...
SHOWERS AND THUNDERSTORMS WILL DEVELOP WEST OF KBIL BY LATE THIS
MORNING AND MOVE EAST DURING THE AFTERNOON. THUNDERSTORMS WILL BE
LIKELY THROUGHOUT THE DAY ACROSS SOUTHEAST MONTANA WITH SOME
THUNDERSTORMS CONTAINING HEAVY RAIN AND LARGE HAIL. LOCAL MVFR TO
IFR CONDITIONS CAN BE EXPECTED IN AND NEAR THE THUNDERSTORM
ACTIVITY. OTHERWISE...VFR CONDITIONS WILL PREVAIL ACROSS THE
FORECAST AREA. THE MOUNTAINS WILL BE OBSCURED AT TIMES. HOOLEY
&&
.PRELIMINARY POINT TEMP/POPS...
TDY SAT SUN MON TUE WED THU
-------------------------------------------------------
BIL 073 052/068 049/078 054/083 058/084 057/083 057/084
5/T 38/T 61/B 11/B 23/T 31/B 10/U
LVM 069 043/066 044/079 046/083 051/083 052/086 051/087
6/T 57/T 51/B 12/T 23/T 31/B 11/U
HDN 075 051/070 048/078 052/083 054/085 056/084 058/085
5/T 38/T 61/B 11/B 22/T 21/B 10/U
MLS 076 056/072 053/080 056/084 059/085 059/086 057/086
5/T 58/T 82/T 12/T 22/T 21/B 11/U
4BQ 075 054/071 051/079 054/085 057/086 057/087 058/088
6/T 68/T 82/T 12/T 22/T 21/U 11/U
BHK 074 055/069 052/076 054/085 059/084 060/086 057/082
7/T 67/T 82/T 12/T 33/T 21/B 11/U
SHR 075 050/069 045/076 049/082 052/084 051/085 052/084
5/T 48/T 61/B 11/B 22/T 21/B 00/U
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
320 AM MDT FRI JUN 21 2013
.SHORT TERM...VALID FOR TDY AND SAT...
SEVERAL OPPORTUNITIES FOR SHOWERS AND STORMS WILL EXIST DURING THE
NEXT 36 HOURS AS THE UPPER-LEVEL TROUGH CENTERED OVER ID AT 09 UTC
HEADS EAST. WHILE THE RESERVOIR OF STRONGEST INSTABILITY WILL STAY
ANCHORED DOWNSTREAM IN THE DAKOTAS...ENOUGH INGREDIENTS WILL EXIST
FOR SOME RISK OF SEVERE STORMS ACROSS PARTS OF OUR AREA TOO.
EARLY THIS MORNING...ELEVATED CONVECTION FED ON A 30+ KT LOW-LEVEL
JET HAS BEEN FORMING EAST OF BILLINGS SINCE ABOUT 06 UTC. INFRARED
SATELLITE IMAGES SUGGEST ANOTHER SUBTLE SHORT WAVE IMPULSE LOCATED
OVER CENTRAL AND NORTHEAST WY WILL MOVE INTO SOUTHEASTERN MT BY 12
UTC. THAT LENDS CREDENCE TO THE LAST SEVERAL HRRR RUNS AND SEVERAL
OTHER HIGH-RESOLUTION...CONVECTION-ALLOWING MODEL SIMULATIONS FROM
00 UTC IN SHOWING ROBUST STORMS DEVELOPING BY MORNING FROM BROADUS
AND EKALAKA TOWARD BAKER. FORECAST SOUNDINGS AND RAP ANALYSES SHOW
MUCAPE ON THE ORDER OF 1000 J/KG...MID LEVEL LAPSE RATES OF 7 C/KM
OR BETTER...AND EFFECTIVE SHEAR OF 60 KT IN SOUTHEASTERN MT DURING
THE MORNING. THUS...SOME SEVERE HAIL IS POSSIBLE...AND WE ACTUALLY
DECIDED TO MENTION THE RISK OF SEVERE STORMS EXPLICITLY WITHIN THE
FORECAST DURING THE MORNING HOURS AT BROADUS...BAKER..AND EKALAKA.
LATER TODAY...WE KEPT THE MENTION OF SEVERE STORMS IN SOUTHEASTERN
MT...AND EXPANDED IT BACK WEST AS FAR AS SHERIDAN AND LODGE GRASS.
THE WESTWARD EXTENSION OF THE SEVERE RISK WAS DONE LARGELY TO GIVE
DUE RESPECT TO CALIBRATED SEVERE THUNDERSTORM PROBABILITIES OFF OF
THE 21 UTC SREF...WHICH ARE FOCUSED IN THE SHERIDAN AREA BY THE 21
TO 00 UTC TIME FRAME. WE HAVE TO ADMIT THOUGH THAT CONFIDENCE WITH
THIS EVENT REMAINS BELOW-NORMAL...AND EARLY-DAY CONVECTION WILL BE
A PLAYER IN HOW THINGS EVOLVE LATER TOO. IF IT IS PERSISTENT...THE
BOUNDARY LAYER MAY NOT DESTABILIZE ENOUGH FOR SURFACE-BASED STORMS
BY LATE AFTERNOON. ON THE OTHER HAND...ENOUGH ELEVATED INSTABILITY
EXISTS TO SUPPORT SEVERE HAIL EVEN IF CONVECTION JUST CONTINUES TO
REGENERATE OVER SOUTHEASTERN MT THROUGH THE DAY. FINALLY...WE ALSO
INCREASED POPS OVER SOUTH CENTRAL MT FROM LIVINGSTON TO BIG TIMBER
AND HARLOWTON THIS AFTERNOON TOO WHERE A DIFFERENT WAVE WILL ALLOW
AT LEAST WEAK AND SCATTERED SHOWERS AND STORMS TO FORM.
TONIGHT...ONCE EVENING CONVECTION WINDS DOWN AND/OR MOVES OFF INTO
THE DAKOTAS...WE MIGHT HAVE A BIT OF A BREAK IN PRECIPITATION. THE
00 UTC ECMWF SUGGESTS ANOTHER WEAK SHORT WAVE TROUGH WILL GENERATE
MORE SHOWERS OR STORMS OVER SOUTHEASTERN MT TOWARD DAYBREAK THOUGH
AND THAT IS A GOOD EXAMPLE OF WHY CHANCE POPS REMAIN NECESSARY FOR
MOST AREAS IN THE 06 TO 12 UTC TIME FRAME.
SAT...THE 500-HPA TROUGH AXIS IS EXPECTED TO SWEEP ACROSS THE AREA
DURING THE AFTERNOON AND EVENING. STRONG QG-FORCING CONCOMITANT TO
THAT TROUGH AND INSTABILITY AHEAD OF THE 500-HPA COLD POOL WILL BE
SUFFICIENT TO GENERATE A HEALTHY BATCH OF CONVECTION. WE INCREASED
POPS INTO THE CATEGORICAL /80 PERCENT/ RANGE ALONG AND EAST OF THE
BILLINGS TO SHERIDAN LINE TO REFLECT THE LIKELIHOOD FOR AT LEAST A
PERIOD OF STORMS AHEAD OF THE TROUGH. THAT MOVE HAS STRONG SUPPORT
FROM THE 00 UTC MULTI-MODEL CONSENSUS. WE WILL ACTUALLY HAVE A LOW
RISK OF SEVERE STORMS AGAIN TOO...ESPECIALLY IF STORMS ARE ABLE TO
GET FAR ENOUGH AHEAD OF THE MID-LEVEL TROUGH AXIS...WHERE THEY MAY
HAVE ACCESS TO STRONGER EFFECTIVE SHEAR. SCHULTZ
.LONG TERM...VALID FOR SUN...MON...TUE...WED...THU...
THE EARLY PART OF THE EXTENDED FORECAST LOOKS UNSETTLED WITH A
DRYING AND WARMING TREND FROM WEDNESDAY ONWARD. THE BEST CHANCE OF
SHOWERS AND THUNDERSTORMS WILL BE MONDAY AND TUESDAY AS SOUTHWEST
FLOW OPENS UP AGAIN AND PROVIDES SEVERAL SHORTWAVES AND DEEPENING
MOISTURE. RAISED POPS FOR TUESDAY AS MODELS HAVE SLOWED DOWN A BIT
ON BUILDING THE RIDGE NOW UNTIL WEDNESDAY.
MODELS WERE CONSISTENT IN BUILDING A STRONG RIDGE INTO THE
NORTHERN ROCKIES WEDNESDAY INTO FRIDAY. THE GFS ACTUALLY HAS A
594DM HEIGHT LINE WORKING INTO SOUTHWEST MONTANA FRIDAY. THAT
WOULD LEAD TO A WARM AND MAINLY DRY FORECAST. WILL HAVE TO WATCH
FOR RIDGE RIDING SHORTWAVES FOR ISOLATED CONVECTION...BUT AT THIS
TIME THE MODELS WERE DRY WITH THE MID LEVEL FLOW. TWH
&&
.AVIATION...
SHOWERS AND THUNDERSTORMS WILL CONTINUE TO DEVELOP EAST OF A
ROUNDUP TO BILLINGS LINE EARLY THIS MORNING. SOME STORMS COULD
CONTAIN HEAVY RAIN AND SMALL HAIL OVER SOUTHEAST MONTANA.
THUNDERSTORM DEVELOPMENT WILL SPREAD INTO WESTERN SECTIONS BY LATE
MORNING. LOCAL MVFR CONDITIONS CAN BE EXPECTED IN THE STRONGER
STORMS. THUNDERSTORMS CHANCES WILL CONTINUE TONIGHT BUT THE MOST
LIKELY LOCATION FOR ADDITIONAL RAINFALL WILL BE OVER THE
SOUTHEAST. TWH
&&
.PRELIMINARY POINT TEMP/POPS...
TDY SAT SUN MON TUE WED THU
-------------------------------------------------------
BIL 073 052/068 049/078 054/083 058/084 057/083 057/084
5/T 38/T 61/B 11/B 23/T 31/B 10/U
LVM 069 043/066 044/079 046/083 051/083 052/086 051/087
6/T 57/T 51/B 12/T 23/T 31/B 11/U
HDN 075 051/070 048/078 052/083 054/085 056/084 058/085
5/T 38/T 61/B 11/B 22/T 21/B 10/U
MLS 076 056/072 053/080 056/084 059/085 059/086 057/086
6/T 58/T 82/T 12/T 22/T 21/B 11/U
4BQ 075 054/071 051/079 054/085 057/086 057/087 058/088
7/T 68/T 82/T 12/T 22/T 21/U 11/U
BHK 074 055/069 052/076 054/085 059/084 060/086 057/082
7/T 67/T 82/T 12/T 33/T 21/B 11/U
SHR 075 050/069 045/076 049/082 052/084 051/085 052/084
5/T 48/T 61/B 11/B 22/T 21/B 00/U
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
638 PM CDT SAT JUN 22 2013
.AVIATION...00Z TAFS FOR KOMA...KLNK...AND KOFK.
MAIN CONCERN IS CONVECTION BREAKING ACROSS ERN NEB TONIGHT.
ACTIVITY IS ALREADY APPEARING ON LATEST RADAR LOOP...AND SHOULD BE
ORGANIZING/INTENSIFYING ALONG A FRONTAL BNDRY EXTENDING FROM ABOUT
KSUX TO KMCK WITHIN THE NEXT HOUR OR SO. DIFFICULT TO DETERMINE WHEN
TSRA WILL BEGIN SLIDING EAST WITH SFC BNDRY AND AFFECT THE TAFS
SITES. FOR NOW AM THINKING TSRA ACTIVITY SHOULD BE REACHING KOFK
FIRST SOMETIME TWD MIDNIGHT...THEN KOMA/KLNK SHORTLY AFTER.
OTHERWISE...VFR CONDITIONS THEN PREVAILING AFT 12Z SUN MORNING.
DEE
&&
.PREV DISCUSSION... /ISSUED 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
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
204 AM CDT FRI JUN 21 2013
.DISCUSSION...
HAVE REMOVED POPS FROM THE NORTHERN CWA FOR THE OVERNIGHT HOURS.
DID KEEP SOUTHERN CWA DRY FOR NOW...BUT WILL NEED TO MONITOR
TRENDS OF CONVECTION IN SOUTH CENTRAL NEB/NORTH CENTRAL KS. SPC
MESOANALYSIS INDICATES CONVECTION IS MOVING INTO INCREASING MUCIN
AS IT PROGRESSES EASTWARD...BUT HAVE LOW CONFIDENCE IN
FORECAST...AS MODELS HAVE NOT CAPTURED ONGOING CONVECTION WELL
ACROSS THE CENTRAL US. THE AIRMASS DOES ACTUALLY BECOME MORE
UNSTABLE FURTHER EASTWARD INTO EASTERN NEB...SO IF CONVECTION
SURVIVES TO THE WESTERN CWA...IT WOULD HAVE A GOOD SHOT AT
SURVIVING INTO THE AREA.
MAYES
&&
.AVIATION...
06Z TAFS FOR KOMA...KLNK...AND KOFK.
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF CYCLE...WITH SOME
MID-LEVEL CLOUDS POSSIBLE THIS MORNING. HAVE INCLUDED A WIND
SHEAR MENTION AT ALL SITES WITH THE POTENTIAL FOR WINDS TO
DECOUPLE IN THE OVERNIGHT/EARLY MORNING HOURS...BUT EXPECT WIND
GUSTS TO PICK UP QUICKLY AGAIN BY MID-MORNING.
MAYES
&&
.PREV DISCUSSION... /ISSUED 304 PM CDT THU JUN 20 2013/
SHORT TERM...TONIGHT THROUGH FRIDAY.
THE PRIMARY FORECAST CONCERNS IN THIS PERIOD ARE STILL THE POTENTIAL
FOR TSTMS AND TEMPERATURES.
UPPER AIR CHARTS FROM THIS MORNING SHOWED THE FOLLOWING. 80 KNOT
WINDS AT 300 MB STRETCHED FROM NORTHERN CALIFORNIA INTO WYOMING. A
LONGWAVE TROUGH WAS OVER THE WESTERN U.S. WITH A WEAK RIDGE OVER THE
PLAINS. 12 HOUR HEIGHT FALLS OF 110 METERS WERE NOTED AT 500 MB OVER
MONTANA. THERMAL RIDGE AT 700 MB EXTENDED FROM MEXICO NORTHWARD INTO
EASTERN COLORADO. THE KOAX 12Z SOUNDING SHOWED A 700 MB TEMP OF 8 C
AND A DEWPOINT OF 4 C. MOIST BAND AT 700 MB EXTENDED FROM WEST
TEXAS UP INTO THE DAKOTAS. THIS MOISTURE WILL BE ONE OF THE THINGS
TO MONITOR IN REGARDS TO CONVECTIVE COVERAGE THE NEXT SEVERAL
DAYS.
SURFACE ANALYSIS EARLY THIS AFTN SHOWED ONE LOW PRESSURE CENTER UP
ALONG THE NORTH DAKOTA/SOUTH DAKOTA BORDER AND ANOTHER IN SOUTHEAST
COLORADO. A COLD FRONT STRETCHED FROM THE LOW OVER THE DAKOTAS DOWN
INTO WESTERN NEBRASKA AND NORTHEAST COLORADO. GUSTY SOUTH WINDS WERE
IN PLACE ACROSS THE FORECAST AREA WITH DEWPOINTS IN THE UPPER 60S
TO AROUND 70.
THIS EVENING...WINDS SHOULD RELAX A LITTLE. THE ATMOSPHERE WILL BE
VERY UNSTABLE...WITH CAPE VALUES IN EXCESS OF 3000 J/KG AND 0-6 KM
SHEAR VALUES OF 20-30 KNOTS. HOWEVER...LIKE YESTERDAY...WE DO NOT
HAVE MUCH OF A FOCUSING MECHANISM FOR STORM DEVELOPMENT. MOST
RECENT HRRR AND 13 KM RAP MODELS SUGGEST SOME STORMS ARE POSSIBLE
ALONG AND EAST OF THE MID LEVEL CAP...AS WELL AS ACROSS PARTS OF
NORTHEAST NEBRASKA. 4 KM WRF-NMM RUN FROM 12Z IS MUCH MORE BULLISH
WITH STORM DEVELOPMENT THIS EVENING FROM THE DAKOTAS/MINNESOTA DOWN
INTO PARTS OF NORTHERN AND WESTERN NEBRASKA. ALTHOUGH THAT IS ONE
POSSIBILITY...TENDED TO SHY AWAY FROM THAT SCENARIO. BOTH THE 12Z
NAM AND GFS ALSO APPEARED TOO WET TONIGHT IN OUR AREA.
FRIDAY...KEPT THUNDERSTORM CHANCES BELOW 15 PERCENT. TEMPERATURES
SHOULD TOP OUT IN THE LOWER OR MID 90S WITH MAX HEAT INDICES UP NEAR
100. WINDS SHOULD INCREASE INTO THE BREEZY OR WINDY CATEGORY AGAIN.
MILLER
LONG TERM...FRIDAY NIGHT THROUGH THURSDAY.
THE BEST CHANCES FOR THUNDERSTORMS IN THIS PERIOD APPEAR TO BE FROM
SATURDAY NIGHT THROUGH SUNDAY NIGHT. A GENERAL BLEND/CONSENSUS OF
THE 12Z MODELS IS THAT A FRONTAL BOUNDARY SHOULD PUSH INTO OUR AREA
FROM THE NORTHWEST SATURDAY NIGHT...THEN LINGER IN THE AREA SUNDAY
AND SUNDAY NIGHT. INSTABILITY AND SHEAR APPEAR THAT THEY WOULD BE
ADEQUATE FOR SOME ORGANIZED SEVERE WEATHER.
THE TENDENCY FOR A TROUGH AT 500 MB OVER THE WESTERN U.S. SHOULD
CONTINUE INTO EARLY NEXT WEEK. AFTER THAT...A MORE SUMMER-LIKE FLOW
PATTERN IS FORECAST TO DEVELOP DUE TO RETROGRESSION. TROUGH AXIS
WILL SHIFT BACK TO AROUND 140 DEGS WEST LONGITUDE WHILE A 500 MB
RIDGE STRENGTHENS OVER THE DESERT SOUTHWEST AND SOUTHERN ROCKIES.
KEPT A MAINLY DRY FORECAST GOING FOR MONDAY INTO THURSDAY...DUE TO
LOW CONFIDENCE. KEPT HIGHS MAINLY IN THE UPPER 80S TO MID 90S WITH
LOWS IN THE UPPER 60S TO MID 70S.
MILLER
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1144 PM MDT THU JUN 20 2013
.AVIATION...
06Z TAF CYCLE
ONLY AN ISOLATED TSTM REMAINS NEAR KROW ATTM...AND WILL BE MOVING
OUT OF THE AREA IN THE NEXT HOUR OR SO. ADDITIONALLY...SMOKE FROM THE
WILDFIRE WEST OF KTCS MAY IMPACT AREAS NEAR AND SE OF KONM
TONIGHT. OTHERWISE...DRYLINE HAS RETREATED FARTHER WEST THAN
ANTICIPATED EARLIER...AND HAS NOW PUSHED THROUGH KSAF. DO NOT
EXPECT A CANYON WIND INTO ABQ BUT CAN EXPECT SOME EAST-SE WIND GUSTS
TO 25KT FOR ANOTHER HOUR OR TWO AT KSAF. STRONGER WINDS CAN BE
EXPECTED ACROSS THE PLAINS WHERE GUSTS BETWEEN 35 AND 40KTS WILL
BE POSSIBLE THROUGH 09-10Z. STRONG SW WINDS WILL RAMP BACK UP
ACROSS CENTRAL AND WESTERN NM ON FRIDAY...WITH GUSTS NEAR 35KTS. A
FEW SHOWERS OR TSTMS WILL AGAIN BE POSSIBLE FRIDAY AFTERNOON AND
EVENING ACROSS THE SE PLAINS. ERRATIC WIND GUSTS AND SMALL HAIL
WOULD BE THE MAIN THREATS. TIMING AND COVERAGE IS QUESTIONABLE...
THUS ONLY INSERTED A VCTS INTO KTCC AND KROW TAFS ATTM. AFTER THE
CONVECTION ENDS FRIDAY EVENING...ANOTHER ROUND OF STRONG SOUTHERLY
WINDS WILL IMPACT EASTERN NM. SE WINDS ASSOCIATED WITH THE
DRYLINE MAY REACH KSAF LATE FRIDAY NIGHT.
34
&&
.PREV DISCUSSION...328 PM MDT THU JUN 20 2013...
SATELLITE AND SURFACE MOISTURE ANALYSIS SHOW THE MOIST AXIS FOCUSED
FROM NORTHERN MEXICO ACROSS SE NEW MEXICO INTO WEST TX. THE LATEST
RADAR TRENDS INDICATE SHOWER AND STORM COVERAGE INCREASING IN THIS
AREA...WHICH COINCIDES WELL WITH THE 17Z HRRR AND RIDGE OF HIGHEST
THETA-E VALUES FROM THE NAM AND GFS. FARTHER WEST THE FOCUS FOR DRY
AND BREEZY CONDITIONS COINCIDES WITH A MID/UPPER LEVEL DRY SLOT
STRETCHING FROM THE BAJA INTO NORTH CENTRAL NM.
THE DEFINITION OF PERSISTENCE WILL HOLD VERY TRUE ACROSS OUR AREA AS
THERE WILL BE VERY LITTLE CHANGE TO THE PATTERN CONFIGURATION THRU
TUESDAY OF NEXT WEEK. EXPECT VERY DRY...BREEZY...AND HOT CONDITIONS
FOR CENTRAL AND WESTERN NM WITH A FEW STORMS FOCUSED OVER THE SE AND
EAST CENTRAL PLAINS. MAX AND MIN TEMPS WILL BE NEARLY THE SAME EVERY
PERIOD AND ABOVE NORMAL HOWEVER NO RECORDS ARE EXPECTED.
UNFORTUNATELY...EVEN HOTTER CONDITIONS BUT WITH LESS WIND WILL OCCUR
FOR THE WEDNESDAY THRU SATURDAY PERIOD OF NEXT WEEK. THIS MAY BE THE
PEAK FOR THE SUMMER WITH A 596 TO 599DM H5 RIDGE CENTERED DIRECTLY
OVER NORTHERN NM AND SOUTHERN CO. THE ECMWF AND GFS THEN SHOW THE
RIDGE WOBBLING WESTWARD INTO NORTHERN AZ ALLOWING A MOIST BACK DOOR
FRONT TO SLIDE INTO THE EAST. THIS WOULD PROVIDE FOR ANOTHER UPTICK
IN STORM COVERAGE HOWEVER CONFIDENCE ON THIS PATTERN IS VERY LOW AS
CONSISTENCY IS POOR FROM MODEL RUN TO RUN.
GUYER
.FIRE WEATHER...
DRY LINE HAS BEEN DRIVEN BACK TO A LINE FROM JUST EAST OF TUCUMCARI
TO NEAR OR JUST W OF DUNKEN...PRETTY MAJOR EROSION CONSIDERING HOW
FAR WEST IT GOT EARLY THIS MORNING. SHOULD WAFT BACK W TONIGHT...BUT
NOT QUITE AS FAR W AS EARLY TODAY. POOR RH RECOVERIES TONIGHT WEST
OF DRY LINE...BASICALLY W OF A RATON TO RUIDOSO LINE. GOOD TO
EXCELLENT RECOVERIES TO E OF THE DRY LINE. SOME SHOWERS AND STORMS
OF WET VARIETY INTO THE EVE NEAR TO E OF TUCUMCARI TO RUIDOSO LINE.
RED FLAG CONDITIONS OF THIS AFTN SHOULD DROP OUT BETWEEN 7 AND 9 PM.
AT LEAST THRU NEXT TUE LOOKING FOR CURRENT PATTERN TO NOT CHANGE
MUCH...GENERALLY A PATTERN OF A FEW TO SCT SHOWERS AND
STORMS...MOSTLY WET...GENERALLY NEAR AND EAST OF A TUCUMCARI TO
RUIDOSO LINE. MAY ON A COUPLE OF OCCASIONS SEE THAT LINE SHIFT UP TO
75 OR 100 MILES FARTHER E OR W DURING THIS PERIOD. SET UP WILL BE A
PACIFIC NW TROUGH AND AN UPPER HIGH GENERALLY CENTERED BETWEEN
CENTRAL TX AND FAR N MEXICO. VERY DRY AIR WILL KEEP COMING ACROSS NW
HALF TO TWO THIRDS OF NM AROUND THE HIGH...RESULTING IN EXTREMELY
LOW RH MINIMUMS AND MANY HOURS OF SINGLE DIGIT HUMIDITIES TO
CONTINUE AS WELL FROM THE CENTRAL MTN CHAIN WEST TO THE AZ BORDER.
THOUGH DRY THE AIRMASS WILL BE UNSTABLE WITH DAYTIME HEATING AND
ABOVE NORMAL TEMPERATURES. HAINES VALUES OF 6 AND EVEN SOME
LOCALIZED SUPER HAINES WILL SHOW UP LATE IN THE DAY FOR AT LEAST THE
NEXT 3 TO 4 DAYS.
AS FOR HIGHLIGHTS...AM CONTINUING THE RED FLAG WARNING INTO THIS EVE
AS BEFORE...AS MORE AREAS THAN NOT ARE VERY NEAR OR A LITTLE OVER
CRITICAL THRESHOLDS. UPGRADED EXISTING WATCH FOR FRI TO RED FLAG
WARNING AND ADDED FIRE ZONE 104...MAINLY WEST AND CENTRAL
PORTIONS...LARGELY BASED ON HOW FAR E DRYLINE PROGRESSED TODAY. SEE
NO REASON FOR IT NOT TO GET AT LEAST AS FAR E AS CLAYTON FRI
AFTN...MAIN REASON THAT ZONE ADDED. STILL BELIEVE MOST OF LOWER
TERRAIN OF 101 WILL BE MARGINAL AT MOST FOR CRITICAL CONDITIONS FRI
AFTN...BUT HIGHER TERRAIN THERE SHOULD DO BETTER AND WITH DEGREE OF
DRYNESS AND HEAT FELT IT BEST TO UPGRADE THAT ZONE ALONG WITH THE
REST. ALSO HOISTED FIRE WX WATCH FOR SAT AFTN AND EARLY EVE FOR 102
THROUGH 104...107 AND WESTERN PART OF 108.
43
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM SATURDAY AFTERNOON THROUGH SATURDAY EVENING
FOR THE FOLLOWING ZONES...NMZ102>104-107-108.
RED FLAG WARNING FROM 1 PM TO 8 PM MDT FRIDAY FOR THE FOLLOWING
ZONES...NMZ101>105.
&&
$$
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1134 PM EDT SAT JUN 22 2013
.SYNOPSIS...
PARTLY TO MOSTLY CLOUDY...WARM...AND INCREASINGLY MUGGY CONDITIONS
WILL PERSIST WELL INTO THE COMING WEEK WITH A SERIES OF WEAK
DISTURBANCES BRINGING AT LEAST A CHANCE OF SHOWERS AND THUNDERSTORMS
ON EACH DAY.
&&
.NEAR TERM /THROUGH SUNDAY/...
A STALLED SURFACE FRONT/CONVERGENCE ZONE LIES FROM NORTHERN NY WEST
ALONG THE NORTHERN SHORE OF LAKE ONTARIO TO NORTH OF LAKE ERIE.
ALONG AND TO THE SOUTH OF THIS BOUNDARY SPC MESOANALYSIS SHOWS
DECENT INSTABILITY IN PLACE WITH WARM AND HUMID AIRMASS IN PLACE.
A WEAK CAP HELD THE ACTIVITY OFF MOST OF THE EARLY EVENING BUT NOW
AREA RADARS ARE SHOWING SHOWER AND THUNDERSTORMS INCREASING OVER
THE NIAGARA PENINSULA SHIFTING TOWARD THE NIAGARA FRONTIER. OVER THE
EASTERN HALF OF LAKE ONTARIO MORE ACTIVITY IS SHIFTING EAST TO THE
NORTH COUNTRY. THESE ARE BEING TRIGGERED BY CONVERGENCE WITH THE
FRONT AND BY OUTFLOW BOUNDARIES WHICH HAVE BEEN LEFT FROM SOME OF
THE STRONGER CELLS. IN THE UPPER LEVELS A SUBTLE SHORTWAVE IS ALSO
CONTRIBUTING TO THIS ACTIVITY WITH SYNOPTIC FORCING. HAVE KEPT
CHANCES FOR SHOWERS AND THUNDERSTORMS IN THE FORECAST FOR MOST OF
THE CWA FROM LAKE ONTARIO SOUTH TO JUST ALONG THE SOUTHERN TIER
COUNTIES WHERE A SLIGHT CHANCE IS IN PLACE. THE LATEST HRRR MODEL
HAS CAUGHT ON TO THIS AND SHOWS THAT ACTIVITY SHOULD PEAK AROUND
MIDNIGHT BEFORE SHIFTING OFF TO THE EAST AND DISSIPATING BY DAYBREAK.
OTHERWISE...EXPECT PARTLY TO MOSTLY CLOUDY SKIES AND VERY MUGGY
CONDITIONS AS HIGHER DEWPOINT AIR IS ADVECTED INTO THE REGION FROM
THE OHIO/MISSISSIPPI VALLEYS. AS SUCH...ONLY EXPECT LOWS TO ONLY
DROP INTO THE MID TO UPPER 60S ACROSS MOST AREAS...THOUGH HIGHER
ELEVATIONS OF THE SOUTHERN TIER AND TUG HILL MAY RUN SLIGHTLY
COOLER...IN THE LOWER 60S.
SUNDAY WILL BE HOT AND MUGGY AS THE REGION WILL REMAIN UNDER THE
INFLUENCE OF WARM AND MOIST RETURN FLOW AROUND THE BERMUDA HIGH
PARKED OVER THE WESTERN ATLANTIC. TEMPERATURES WILL TOP OUT IN THE
MID TO UPPER 80S AND WITH DEWPOINTS IN THE UPPER 60S...IT WILL BE
QUITE STICKY INDEED. THE INCREASING MOISTURE IN THE BOUNDARY LAYER
SHOULD CREATE A MORE FAVORABLE ENVIRONMENT FOR T HE DEVELOPMENT OF
AFTERNOON SHOWERS AND THUNDERSTORMS...PARTICULARLY INLAND FROM THE
STABILIZING INFLUENCE OF THE LAKES. HOWEVER...THE PRESENCE OF A
BROAD UPPER LEVEL RIDGE OVER THE REGION MEANS THAT ANY ACTIVITY WILL
LIKELY BE SCATTERED AND NOT WELL ORGANIZED.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
SUNDAY NIGHT LEFTOVER SHOWERS AND THUNDERSTORMS FROM THE DAYTIME
HEATING WILL GRADUALLY DIMINISH THROUGH THE EVENING HOURS. IT WILL
REMAIN WARM OVERNIGHT WITH A LIGHT SOUTHERLY FLOW. OVERNIGHT LOWS
WILL ONLY DROP BACK INTO UPPER 60S...WITH SEVERAL LOCATIONS ACROSS
THE LAKE PLAIN LIKELY TO NOT FALL PAST THE 70F MARK. A WARM NIGHT
WILL ALSO BE MUGGY AS DEW POINTS WILL NOT BE TOO MUCH COOLER.
A SHORTWAVE ADVANCING NORTHWARD UP THE WESTERN SPINE OF THE
APPALACHIANS MAY BRING MORE SHOWERS AND THUNDERSTORMS INTO FAR
WESTERN NEW YORK LATE IN THE OVERNIGHT PERIOD. GIVEN THE WARM AND
HUMID CONDITIONS TO THE AIRMASS SOUNDINGS OF BOTH THE NAM AND GFS
SHOW 300 TO 500 J/KG OF ELEVATED INSTABILITY OVER SW NYS BY DAWN
MONDAY MORNING. LIFT AHEAD OF THIS LITTLE SHORTWAVE...AND SOME
INCREASE IN MOISTURE FROM THE ATLANTIC WITH THIS FEATURE WILL LIKELY
SPAWN A FEW SHOWERS AND PERHAPS THUNDERSTORMS LATE SUNDAY NIGHT AND
INTO MONDAY MORNING ACROSS WESTERN NEW YORK.
THROUGH THE DAY ON MONDAY THIS FEATURE WILL REACH THE MEAN WESTERLY
FLOW ACROSS THE NORTHERN US...AND BEGIN TO ADVANCE EASTWARD. AS THE
DAY CARRIES ON THE FOCUS FOR SHOWERS AND THUNDERSTORMS WILL ALSO BE
TOWARDS OUR EASTERN SECTIONS...WITH LAKE BREEZE BOUNDARIES ALSO
SUPPLYING BOUNDARIES FOR CONVECTIVE ACTIVITY. AS THE DAY PROGRESSES
AND THE LAND MASS WARMS WELL INTO THE 80S A SOUTHWEST WIND OFF BOTH
LAKE ERIE AND ONTARIO WILL DEVELOP. THIS SOUTHWEST WIND SHOULD
STABILIZE THE ATMOSPHERE SUCH THAT THERE WILL ONLY BE A SLIGHT
CHANCE FOR A SHOWER OR THUNDERSTORM THROUGH THE AFTERNOON AND
EVENING HOURS DOWNWIND OF BOTH LAKES ERIE AND ONTARIO. TEMPERATURES
AT 850 HPA AVERAGE AROUND 16C ACROSS THE REGION. THIS WILL BRING
AFTERNOON HIGHS INTO THE MID 80S...WITH A POSSIBLE 90F READING IN
THE TRADITIONALLY WARMER GENESEE VALLEY. TEMPERATURES WILL BE COOLER
DOWNWIND OF LAKE ERIE AND ONTARIO...AND WITH THE LIGHT SOUTHWEST
WINDS...JUST THE IMMEDIATE LAKE ONTARIO SHORELINE WILL PRESENT
COOLER TEMPERATURES THAN INLAND LOCATIONS.
MONDAY EVENING AGAIN SHOWERS AND THUNDERSTORMS WILL DIMINISH WITH
THE LOSS OF DAYTIME HEATING AND THE DEPARTURE OF THE UPPER LEVEL
SHORTWAVE. LATER IN THE NIGHT SHOWERS AND THUNDERSTORMS THAT
BLOSSOMED OVER THE ONTARIO PENINSULA MAY DRIFT EASTWARD INTO OUR FAR
WESTERN AREAS. WITH SOME ELEVATED INSTABILITY LINGERING IN THE WARM
AND MUGGY AIRMASS WILL CONTINUE WITH A LOW CHANCE POP ACROSS WESTERN
NEW YORK LATER IN THE NIGHT. OVERNIGHT LOWS WILL CONTINUE TO BE WARM
WITH MUGGINESS REMAINING WITH LOWS SIMILAR TO SUNDAY NIGHT...UPPER
60S AND A FEW LOW 70 READINGS.
ON TUESDAY ANOTHER COMPACT SHORTWAVE WILL CREST THE EASTERN
RIDGE...FURTHER SUPPRESSING IT TO THE SOUTH. THIS SHORTWAVE
ENCOUNTERING THE WARM AND MOIST AIRMASS OVER THE GREAT LAKES REGION
WILL PRODUCE ADDITIONAL SHOWERS AND THUNDERSTORMS. WITH THE DAYTIME
INSTABILITY OF 1000 TO 2000 J/KG ACROSS INLAND AREAS WILL AGAIN HAVE
THE HIGHEST POPS FOR SHOWERS AND THUNDERSTORMS HERE...BUT LIKE
MONDAY WILL PAINT CHANCE POPS ACROSS THE ENTIRE CWA. TUESDAY NIGHT
ACTIVITY MAY DIMINISH SLOWER WITH THE SHORTWAVE STILL PASSING ACROSS
THE CWA. WILL LEAVE A CHANCE FOR SHOWERS AND THUNDERSTORMS THROUGH
THE NIGHT...ESPECIALLY ACROSS WNY WHERE ADDITIONAL SHOWERS AND
THUNDERSTORMS MAY CARRY INTO THE REGION FROM THE WEST.
TEMPERATURES ALOFT AT 850 HPA ON TUESDAY MAY ACTUALLY WARM SOME AHEAD OF
THE COMPACT SHORT WAVE WITH TEMPERATURES AT 5K FEET PEAKING AROUND
17 TO 18C. HOWEVER WITH CLOUDS LIKELY TO BE A LITTLE MORE ABUNDANT
AFTERNOON HIGHS WILL BE SIMILAR TO MONDAY...WITH HIGHS IN THE MID
80S. WITH NO CHANGE IN AIRMASS OVERNIGHT LOWS AND HUMIDITY WILL BE
SIMILAR TO RECENT NIGHTS WITH LOWS IN THE MID TO UPPER 60S...AND
CONTINUED MUGGY WITH DEW POINTS IN THE MID 60S AS WELL.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
SUMMERS WARMTH AND HUMIDITY WILL GRIP THE REGION TO START THIS TIME
PERIOD...FOLLOWED BY COOLER AIRMASS TO START NEXT WEEKEND.
THUNDERSTORMS WILL BE POSSIBLE THROUGH THE PERIOD...ESPECIALLY ON
THE BOUNDARY BETWEEN THESE TWO AIRMASSES WHERE SOME THUNDERSTORMS
COULD BE STRONG.
ON WEDNESDAY A WEAK COLD FRONT WILL BE DROPPING SOUTHWARD THROUGH
NEW YORK STATE. OUR REGION WILL BE ON THE TAIL END OF THIS
FRONT...LEAVING JUST A CHANCE FOR SHOWERS AND THUNDERSTORMS...GIVEN
THAT 1000 TO 1500 J/KG OF SBCAPE WILL STILL BE PRESENT. WARM AND
HUMID CONDITIONS WILL CONTINUE WITH WIDESPREAD HIGHS IN THE LOWER TO
MID 80S EXPECTED...WITH DEWPOINTS IN THE MID 60S. THUNDERSTORMS THAT
DO DEVELOP WEDNESDAY WILL END THROUGH THE EVENING HOURS AS DAYTIME
HEATING DIMINISHING AND THE WEAK SFC COLD FRONT...A TRIGGERING
BOUNDARY FOR THUNDERSTORMS...FOCUSES MORE TO THE EAST.
ON THURSDAY A FAIRLY POTENT SHORTWAVE WILL BE CROSSING FROM SOUTHERN
CANADA INTO THE NORTHERN GREAT LAKES. AS THIS SHORTWAVE ROUNDS THE
UPPER LEVEL RIDGE THAT HAS BEEN ANCHORED OVER THE WEST IT WILL DROP
SOUTHEASTWARD AND CARVE AN UPPER LEVEL TROUGH OVER THE CENTRAL GREAT
LAKES. AHEAD OF THIS FEATURE HIGHER THETA-E AIR WILL BEGIN TO PUSH
NORTHEASTWARD...INCREASING THE INSTABILITY OVER THE OHIO VALLEY AND
EASTERN GREAT LAKES REGION. THUNDERSTORMS WILL BE POSSIBLE THURSDAY
WITH THE DAYTIME INSTABILITY AND A CHANCE FOR STORMS WILL CONTINUE
AS POSSIBLE UPSTREAM THUNDERSTORM COMPLEXES POSSIBLY CLIP WESTERN
NEW YORK THROUGH THE NIGHT.
AS WE GET INTO FRIDAY...THIS MAY BE THE MOST ACTIVE DAY AS THE CLASH
BETWEEN THE WARM AND HUMID AIRMASS OVER OUR REGION IS ENCROACHED
UPON BY THE UPPER LEVEL TROUGH AND COLDER TEMPERATURES. MID LEVEL
THETA-E WILL PEAK THIS DAY AHEAD OF THE POOL OF COLDER AIR...THOUGH
THE HIGHEST VALUES WILL REMAIN ACROSS THE OHIO VALLEY. AT THE
SURFACE A SURFACE LOW WILL CUT ACROSS SOUTHERN ONTARIO CANADA AND
DRAG A COLD FRONT TOWARDS WESTERN NEW YORK FRIDAY AFTERNOON. IT IS
POSSIBLE THAT THE COLD FRONT DOES NOT PASS THROUGH THE REGION TILL
FRIDAY NIGHT MAINTAINING THE THREAT FOR THUNDERSTORMS THROUGH THE
NIGHT. WITH UPPER LEVEL HEIGHT FALLS...AND PLENTY OF MOISTURE
COMBINED WITH LIFT FROM THE COLD FRONT EXPECT SHOWERS AND
THUNDERSTORMS TO DEVELOP THROUGH THE DAY WITH ACTIVITY SLOWLY
DRIFTING EASTWARD WITH THE ADVANCEMENT OF THE COLD FRONT THROUGH THE
NIGHT.
THE 12Z GFS BRINGS THE COLD FRONT TO OUR EAST BY SATURDAY....WHILE
THE 12Z ECMWF IS SLIGHTLY SLOWER. WITH BOTH MODELS PLACING THE UPPER
LEVEL TROUGH JUST TO OUR WEST THROUGH THE DAY WILL MAINTAIN THE
CHANCE FOR A SHOWER. THERE WILL STILL BE A CHANCE FOR A SHOWER OR
THUNDERSTORM WITH THE COLDER POOL OF AIR OVERHEAD...AND A STILL WARM
SURFACE WITH TEMPERATURES IN THE MID TO UPPER 70S.
TEMPERATURES WEDNESDAY THROUGH FRIDAY WILL BE SOME 5 TO 10 DEGREES
ABOVE NORMAL...WITH HIGHS IN THE MID TO UPPER 80S. NIGHTTIME LOWS
WILL ONLY DROP BACK INTO THE MID TO UPPER 60S...WITH THE POSSIBILITY
OF LOWS NOT FALLING BELOW 70F ON THE LAKE PLAIN EACH NIGHT.
&&
.AVIATION /04Z SUNDAY THROUGH THURSDAY/...
SHOWER AND THUNDERSTORM ACTIVITY HAS PICKED UP LATE THIS EVENING
ACROSS THE NIAGARA PENINSULA WHICH WILL SHIFT EAST TO KBUF/KIAG
THROUGH MIDNIGHT OR SO. SAME SCENARIO FOR KART AND EVENTUALLY KROC.
MAINLY VFR CIGS/VIS EXCEPT IN CONVECTION WHERE MVFR/IFR VIS IS
POSSIBLE. KART CONTINUE IN AND OUT OF MVFR/IFR VIS IN LIGHT FOG
AFTER RECEIVING NUMEROUS SHOWERS EARLIER AND WITH MORE ON THE WAY. ALL
GUIDANCE KEEPS KART BELOW VFR THROUGH THE NIGHT WITH THE GFS SHOWING
1/2SM FG OVER NIGHT BUT LIFTS TO VFR BY LATER TOMORROW MORNING. WENT
AHEAD WITH IFR VIS AFTER 07Z WHEN MORE SHOWERS AND POSSIBLE STORMS
INCREASE MOISTURE AT KART. HAVE STAYED AWAY FROM GOING TO IFR VIS
OVERNIGHT IN FOG FOR NOW BUT KEEP MVFR THROUGH 15Z. VFR EXPECTED
SUNDAY AFTER ANY LINGERING FOG BURNS OFF AT KART. MOST TAFS WILL
STAY DRY AS ANY CONVECTION ON SUNDAY LOOKS TO REMAIN WELL INLAND.
OUTLOOK...
SUNDAY NIGHT THROUGH THURSDAY...MAINLY VFR WITH A CHANCE OF SHOWERS
AND THUNDERSTORMS.
&&
.MARINE...
SOUTHWESTERLY FLOW OF 15 KNOTS OR LESS WILL PERSIST ACROSS THE LOWER
GREAT LAKES AT LEAST THROUGH THE MIDDLE OF THE COMING WEEK AS THE
BERMUDA HIGH WILL REMAIN FIRMLY ENTRENCHED OVER THE WESTERN
ATLANTIC. A SERIES OF WEAK UPPER LEVEL DISTURBANCES WILL BRING A
CHANCE OF SHOWERS AND THUNDERSTORMS TO THE REGION FOR THE NEXT
SEVERAL DAYS AS WELL.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...WOOD
NEAR TERM...SMITH/WOOD
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...SMITH
MARINE...SMITH/WOOD
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
742 PM EDT SAT JUN 22 2013
.SYNOPSIS...
HIGH PRESSURE BUILDING INTO THE NORTHEAST WILL BRING WARM
AIR 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/...
7PM...SHWRS WEAKENING OVER THE NRN CWA THIS EVENING. WILL KEEP A
SLGT CHANCE FOR THE EVENING BUT PCPN IS OVER THE FOR THE MOST
PART. CLDS AND RAIN DID KEEP TEMPS A BIT LWR ACROSS THE NRN CWA SO
HAVE ADJUSTED THE TEMPS AND MAX ACCORDINGLY. WITH THE
PCPN...EXPANDED THE CVRG OF FOG OVRNGT OVER THE NRN AREAS. PRVS
DISC BLO...
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 /00Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS EXPECTED AT ALL OF THE TAF SITES INTO THE EARLY
MORNING. PATCHY MVFR AND IFR VSBYS WILL DEVELOP IN THE RIVER
VALLEYS FROM 08Z-12Z INCLUDING AT ELM. OTHERWISE VFR CONDITIONS
WILL CONTINUE ON SUNDAY. ISOLATED THUNDERSTORMS WILL DEVELOP
SUNDAY AFTERNOON... WITH COVERAGE TOO SMALL TO INCLUDE IN ANY TAF
SITES AT THIS TIME.
WINDS WILL BE VARIABLE AT LESS THAN 10 KTS TONIGHT... THEN
SOUTHWEST INCREASING TO AROUND 10 KTS ON SUNDAY.
OUTLOOK...SUN NGT 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...DGM/PVN
NEAR TERM...DGM/PVN
SHORT TERM...PVN
LONG TERM...JAB
AVIATION...MSE
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
706 PM EDT SAT JUN 22 2013
.SYNOPSIS...
HIGH PRESSURE BUILDING INTO THE NORTHEAST WILL BRING WARM
AIR 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/...
7PM...SHWRS WEAKENING OVER THE NRN CWA THIS EVENING. WILL KEEP A
SLGT CHANCE FOR THE EVENING BUT PCPN IS OVER THE FOR THE MOST
PART. CLDS AND RAIN DID KEEP TEMPS A BIT LWR ACROSS THE NRN CWA SO
HAVE ADJUSTED THE TEMPS AND MAX ACCORDINGLY. WITH THE
PCPN...EXPANDED THE CVRG OF FOG OVRNGT OVER THE NRN AREAS. PRVS
DISC BLO...
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 /23Z 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...DGM/PVN
NEAR TERM...DGM/PVN
SHORT TERM...PVN
LONG TERM...JAB
AVIATION...JAB
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
656 PM EDT FRI JUN 21 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 SATURDAY MORNING/...
AS OF 323 PM EDT FRIDAY...TONIGHT BEGINS WITH CLEAR TO PARTLY
CLOUDY SKIES THIS EVENING...BUT CLOUD COVER WILL INCREASE AFTER
MIDNIGHT AS DEBRIS CLOUDS FROM A MESOSCALE CONVECTIVE COMPLEX AND
IT`S ASSOCIATED VORTICITY OVER THE UPPER GREAT LAKES RIDES EAST
SOUTHEASTWARD ALONG THE A DEVELOPING WARM FRONTAL BOUNDARY OVER
OUR AREA. TEMPS WILL RUN RIGHT AROUND SEASONAL NORMALS IN THE 50S
TO NEAR 60 IN THE VALLEYS.
&&
.SHORT TERM /6 AM SATURDAY 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 FOREAST. 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 /00Z 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...SISSON
SHORT TERM...SISSON
LONG TERM...TABER
AVIATION...TABER/LOCONTO
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
348 PM EDT FRI JUN 21 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 SATURDAY MORNING/...
AS OF 323 PM EDT FRIDAY...TONIGHT BEGINS WITH CLEAR TO PARTLY
CLOUDY SKIES THIS EVENING...BUT CLOUD COVER WILL INCREASE AFTER
MIDNIGHT AS DEBRIS CLOUDS FROM A MESOSCALE CONVECTIVE COMPLEX AND
IT`S ASSOCIATED VORTICITY OVER THE UPPER GREAT LAKES RIDES EAST
SOUTHEASTWARD ALONG THE A DEVELOPING WARM FRONTAL BOUNDARY OVER
OUR AREA. TEMPS WILL RUN RIGHT AROUND SEASONAL NORMALS IN THE 50S
TO NEAR 60 IN THE VALLEYS.
&&
.SHORT TERM /6 AM SATURDAY 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 FOREAST. 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 /20Z FRIDAY THROUGH WEDNESDAY/...
THROUGH 18Z SATURDAY...AVIATION CHALLENGE WL BE POTENTIAL FOR RAIN
SHOWERS WITH EMBEDDED RUMBLES OF THUNDER AFT 12Z SAT. CRNT VIS
SATL PIC SHOWS A FEW FAIR WX CUMULUS CLOUDS ACRS THE
MTNS...OTHERWISE SKIES ARE CLR ATTM. VFR CONDITIONS WL PREVAIL
OVERNIGHT WITH CLOUDS INCREASING FROM WEST TO EAST ACRS OUR TAF
SITES. THE COMBINED OF S/W ENERGY AND MID LVL MOISTURE WL RIDE
ALONG A SFC BOUNDARY ON SATURDAY TO PRODUCE SHOWERS LIKELY. WL
MENTION VCSH ATTM AFT 15Z FOR OUR CENTRAL/NORTHERN TAF
SITES...WITH NO RESTRICTION TO VIS ANTICIPATED. LIGHT SOUTH TO
SOUTHWEST WINDS TODAY...WL BECM TRRN DRIVEN OVERNIGHT...BEFORE
SHIFTING BACK TO THE SOUTH ON SATURDAY.
OUTLOOK 18Z SATURDAY 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...SISSON
SHORT TERM...SISSON
LONG TERM...TABER
AVIATION...TABER
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
323 PM EDT FRI JUN 21 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 SATURDAY MORNING/...
AS OF 323 PM EDT FRIDAY...TONIGHT BEGINS WITH CLEAR TO PARTLY
CLOUDY SKIES THIS EVENING...BUT CLOUD COVER WILL INCREASE AFTER
MIDNIGHT AS DEBRIS CLOUDS FROM A MESOSCALE CONVECTIVE COMPLEX AND
IT`S ASSOCIATED VORTICITY OVER THE UPPER GREAT LAKES RIDES EAST
SOUTHEASTWARD ALONG THE A DEVELOPING WARM FRONTAL BOUNDARY OVER
OUR AREA. TEMPS WILL RUN RIGHT AROUND SEASONAL NORMALS IN THE 50S
TO NEAR 60 IN THE VALLEYS.
&&
.SHORT TERM /6 AM SATURDAY 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 FOREAST. 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 339 AM EDT FRIDAY...FOR THE EXTENDED PERIOD...THE ENTIRE
NORTH COUNTRY WILL SEE WARM/HOT TEMPS...HUMID CONDITIONS AND THE
CHANCE FOR RW/TRW FOR ALMOST THE ENTIRE TIMEFRAME. THE SETUP FOR
THE AFOREMENTIONED CONDITIONS... LATEST MDLS CONTINUE TO SHOW
LARGE BLOCKING RIDGE TO SET UP OVER SOUTHERN AND EASTERN PORTIONS
OF THE COUNTRY. SFC FLOW AROUND THE RIDGE WILL BRING IN WARM/HUMID
AIR...WHICH CURRENTLY RESIDES OVER CENTRAL/SOUTHERN PORTIONS OF
THE COUNTRY. 850/925 TEMPS THRU PERIOD RANGE FROM +18C TO
+24C...SUPPORTING MDL GUIDANCE NUMBERS OF M/U 80S TO AROUND 90F IN
SPOTS...AND OVERNGT LOWS IN THE U50S TO M60S. MANY AREA THOUGH
WILL HAVE DAYTIME HIGHS TEMPERED BY CLD COVER FROM DIURNAL
HEATING(CREATING TRW/RW)...AND A COUPLE OF WK SYSTEMS RIDING OVER
NORTHERN PORTIONS OF THE RIDGE...WITH MAIN FOCUS OVER N NY. GOING
INTO NEXT WED/THURS MDLS DO DIFFER ON TIMING/PLACEMENT OF
APPROACHING LOW DIGGING OUT OF CENTRAL CANADA. W/ GFS BRINGING
THRU GREAT LKS AND LATEST ECMWF HAVE SYSTEM DIVE SE FROM CENTRAL
CANADA AND INTO CWA. BOTH MDLS SUGGEST PRECIP WILL OCCUR W/ MAIN
FOCUS OVER WESTERN PORTIONS OF THE CWA...SO HAVE CONCENTRATED
HIGHER POPS THERE. OVERALL THESE TWO DAYS HAVE BETTER CHANCES FOR
CONVECTION BROUGHT ABOUT BY DYNAMICS OF APPROACHING LOW/TROUGH.
BEGINNING PORTION OF FORECAST PERIOD WILL SEE ANY TRW FOCUS ALONG
NORTHERN HALF OF CWA AS RIDGE WILL KEEP SOUTHWARD PUSH TO A
MINIMUM.
&&
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
THROUGH 18Z SATURDAY...AVIATION CHALLENGE WL BE POTENTIAL FOR RAIN
SHOWERS WITH EMBEDDED RUMBLES OF THUNDER AFT 12Z SAT. CRNT VIS
SATL PIC SHOWS A FEW FAIR WX CUMULUS CLOUDS ACRS THE
MTNS...OTHERWISE SKIES ARE CLR ATTM. VFR CONDITIONS WL PREVAIL
OVERNIGHT WITH CLOUDS INCREASING FROM WEST TO EAST ACRS OUR TAF
SITES. THE COMBINED OF S/W ENERGY AND MID LVL MOISTURE WL RIDE
ALONG A SFC BOUNDARY ON SATURDAY TO PRODUCE SHOWERS LIKELY. WL
MENTION VCSH ATTM AFT 15Z FOR OUR CENTRAL/NORTHERN TAF
SITES...WITH NO RESTRICTION TO VIS ANTICIPATED. LIGHT SOUTH TO
SOUTHWEST WINDS TODAY...WL BECM TRRN DRIVEN OVERNIGHT...BEFORE
SHIFTING BACK TO THE SOUTH ON SATURDAY.
OUTLOOK 18Z SATURDAY 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...SISSON
SHORT TERM...SISSON
LONG TERM...JN
AVIATION...TABER
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
240 PM EDT FRI JUN 21 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 PM THIS EVENING/...
AS OF 239 PM EDT FRIDAY...PREVIOUS FORECAST ON TRACK FOR HIGHS IN
THE UPPER 70S TO LOWER 80S UNDER PARTLY TO MOSTLY SUNNY SKIES WITH
SOME FAIR WEATHER CUMULUS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
AS OF 239 PM EDT FRIDAY...TONIGHT BEGINS WITH PARTLY CLOUDY SKIES
THIS EVENING...BUT CLOUD COVER WILL INCREASE TOWARDS MIDNIGHT AS
DEBRIS CLOUDS FROM A MESOSCALE CONVECTIVE COMPLEX AND IT`S
ASSOCIATED VORTICITY OVER THE UPPER GREAT LAKES RIDES EAST
SOUTHEASTWARD ALONG THE A DEVELOPING WARM FRONTAL BOUNDARY OVER OUR
AREA. TEMPS WILL RUN RIGHT AROUND SEASONAL NORMALS IN THE 50S TO
NEAR 60 IN THE VALLEYS.
FOR 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. EL RIDGE ACROSS THE GREAT LAKES REGION AND
DEVELOP SHOWERS AND THUNDERSTORMS ACROSS THE BTV CWA DURING THE
MID-DAY TO EVENING HOURS. BUT 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 SUGGEST AND
SLIGHT COOLER TEMPERATURES. HAVE STAYED MAINLY NEAR 80 COOLER
NORTHEAST AND WARMER SOUTHWEST, BUT 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 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. 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 AS WARMER AND MORE HUMID AIR PUSHES IN AS THE WARM FRONT
LIFTS NORTHEAST.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 339 AM EDT FRIDAY...FOR THE EXTENDED PERIOD...THE ENTIRE
NORTH COUNTRY WILL SEE WARM/HOT TEMPS...HUMID CONDITIONS AND THE
CHANCE FOR RW/TRW FOR ALMOST THE ENTIRE TIMEFRAME. THE SETUP FOR
THE AFOREMENTIONED CONDITIONS... LATEST MDLS CONTINUE TO SHOW
LARGE BLOCKING RIDGE TO SET UP OVER SOUTHERN AND EASTERN PORTIONS
OF THE COUNTRY. SFC FLOW AROUND THE RIDGE WILL BRING IN WARM/HUMID
AIR...WHICH CURRENTLY RESIDES OVER CENTRAL/SOUTHERN PORTIONS OF
THE COUNTRY. 850/925 TEMPS THRU PERIOD RANGE FROM +18C TO
+24C...SUPPORTING MDL GUIDANCE NUMBERS OF M/U 80S TO AROUND 90F IN
SPOTS...AND OVERNGT LOWS IN THE U50S TO M60S. MANY AREA THOUGH
WILL HAVE DAYTIME HIGHS TEMPERED BY CLD COVER FROM DIURNAL
HEATING(CREATING TRW/RW)...AND A COUPLE OF WK SYSTEMS RIDING OVER
NORTHERN PORTIONS OF THE RIDGE...WITH MAIN FOCUS OVER N NY. GOING
INTO NEXT WED/THURS MDLS DO DIFFER ON TIMING/PLACEMENT OF
APPROACHING LOW DIGGING OUT OF CENTRAL CANADA. W/ GFS BRINGING
THRU GREAT LKS AND LATEST ECMWF HAVE SYSTEM DIVE SE FROM CENTRAL
CANADA AND INTO CWA. BOTH MDLS SUGGEST PRECIP WILL OCCUR W/ MAIN
FOCUS OVER WESTERN PORTIONS OF THE CWA...SO HAVE CONCENTRATED
HIGHER POPS THERE. OVERALL THESE TWO DAYS HAVE BETTER CHANCES FOR
CONVECTION BROUGHT ABOUT BY DYNAMICS OF APPROACHING LOW/TROUGH.
BEGINNING PORTION OF FORECAST PERIOD WILL SEE ANY TRW FOCUS ALONG
NORTHERN HALF OF CWA AS RIDGE WILL KEEP SOUTHWARD PUSH TO A
MINIMUM.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
THROUGH 18Z SATURDAY...AVIATION CHALLENGE WL BE POTENTIAL FOR RAIN
SHOWERS WITH EMBEDDED RUMBLES OF THUNDER AFT 12Z SAT. CRNT VIS
SATL PIC SHOWS A FEW FAIR WX CUMULUS CLOUDS ACRS THE
MTNS...OTHERWISE SKIES ARE CLR ATTM. VFR CONDITIONS WL PREVAIL
OVERNIGHT WITH CLOUDS INCREASING FROM WEST TO EAST ACRS OUR TAF
SITES. THE COMBINED OF S/W ENERGY AND MID LVL MOISTURE WL RIDE
ALONG A SFC BOUNDARY ON SATURDAY TO PRODUCE SHOWERS LIKELY. WL
MENTION VCSH ATTM AFT 15Z FOR OUR CENTRAL/NORTHERN TAF
SITES...WITH NO RESTRICTION TO VIS ANTICIPATED. LIGHT SOUTH TO
SOUTHWEST WINDS TODAY...WL BECM TRRN DRIVEN OVERNIGHT...BEFORE
SHIFTING BACK TO THE SOUTH ON SATURDAY.
OUTLOOK 18Z SATURDAY 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...SISSON
SHORT TERM...SISSON
LONG TERM...JN
AVIATION...TABER
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1242 PM EDT FRI JUN 21 2013
.SYNOPSIS...
TODAY IS THE OFFICIAL START OF SUMMER. A SLOW-MOVING FRONT OFFSHORE
WILL DRIFT WEST AND ONSHORE EARLY SATURDAY...INCREASING THE RISK FOR
SHOWERS AND THUNDERSTORMS. TYPICAL SUMMERTIME WEATHER IS EXPECTED
NEXT WEEK WITH BERMUDA HIGH PRESSURE AND THE PIEDMONT TROUGH
BECOMING THE DOMINANT SURFACE FEATURES.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 100 PM FRIDAY...FAIRLY THICK CLOUDS IN THE WILMINGTON/CAPE
FEAR AREA HAVE HELD TEMPERATURES TO 80 DEGREES SO FAR...WITH NO
INLAND CONVECTION SO FAR. I HAVE TRIMMED POPS BACK TO ONLY 30
PERCENT THROUGH 6 PM FOR THIS AREA GIVEN RECENTLY HRRR RUNS SHOWING
LESSER INDICATED COVERAGE ON ITS LAST SEVERAL RUNS. ALONG THE SC
COAST THE HRRR CONTINUES TO INDICATE SOME POTENTIAL FOR SCATTERED
SHOWER/T-STORM DEVELOPMENT THIS AFTERNOON SO DESPITE THE CURRENT
MOSTLY CLEAR/PARTLY CLOUDY SKIES I AM MAINTAINING 20-40 PERCENT
CHANCES THERE. NO SIGNIFICANT CHANGES HAVE BEEN MADE FARTHER INLAND
WHERE MAINLY SUNNY SKIES HAVE ALLOWED TEMPERATURES TO RISE INTO THE
LOWER 80S ALONG AND WEST OF THE I-95 CORRIDOR. SOME UPPER 80S MAY
EVEN OCCUR FOR HIGHS TODAY FROM LUMBERTON WEST THROUGH
BENNETTSVILLE. PREVIOUS DISCUSSION FROM 1030 AM FOLLOWS...
YESTERDAY`S STALLED FRONT IS SHOWN ON SATELLITE IMAGERY AND ON MODEL
ANALYSES TO BE LOCATED ABOUT 50 MILES SOUTHEAST OF BALD HEAD ISLAND
NC. THE FRONT WILL MOVE A LITTLE CLOSER TO THE COAST TODAY BUT
SHOULD REMAIN OFFSHORE. THIS MOVEMENT IS BEING AIDED BY HIGH
PRESSURE OVER THE WEST-CENTRAL ATLANTIC DEVELOPING A SUBSTANTIAL
FETCH OF EAST AND SOUTHEAST WINDS ACROSS THE BAHAMAS AND WESTERN
ATLANTIC. A RIBBON OF DEEP MID LEVEL MOISTURE LOCATED OVER THE FRONT
WILL ALSO ADVECT CLOSER TO THE COAST TODAY AND TONIGHT...AIDED BY
THE CIRCULATION AROUND A WEAK MID AND UPPER LEVEL LOW ACROSS
NORTHERN GEORGIA AND EASTERN TENNESSEE.
MORNING LOW CLOUDS ALONG THE COAST ARE BURNING OFF BUT THERE IS A
DEEP ENOUGH LOW-LEVEL INVERSION ON THE 12Z MHX AND CHS SOUNDINGS
THAT THIS MOISTURE WILL LIKELY JUST CREATE A STRATOCUMULUS DECK A
LITTLE HIGHER UP...AT LEAST UNTIL THIS INVERSION CAN BREAK AS
TEMPERATURES RISE TO AROUND 80 BY NOON OR SO. AT THIS POINT ISOLATED
SHOWERS MAY BEGIN TO DEVELOP WITH LIMITED CONVECTIVE INSTABILITY
(CAPE: 500-800 J/KG) IN REGIONS CLOSE ENOUGH TO THE COAST TO HAVE
DEWPOINTS IN THE MID 60S OR HIGHER. FARTHER INLAND FOR FLORENCE AND
LUMBERTON THE AIRMASS IS CONSIDERABLY DRIER AND ANY CUMULUS CLOUD
DEVELOPMENT WILL BE SUBSTANTIALLY DELAYED UNTIL MID TO LATE
AFTERNOON WHEN ENOUGH MOISTURE FINALLY ADVECTS THAT FAR WEST.
CHANGES TO THE FORECAST THIS MORNING INCLUDE RAISING HIGH
TEMPERATURE FORECASTS INLAND A DEGREE OR TWO...CUTTING POPS BY 10-20
PERCENT THROUGH THE DAY AND REMOVING REMOVING POPS WEST OF
INTERSTATE 95...AND ADJUSTING CLOUD COVER FORECASTS TO REFLECT THE
PRESENCE OF THE SUBSTANTIAL AREA OF DRY AIR INLAND.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 3 AM FRIDAY...WEAK QUASI-STATIONARY FRONT/COASTAL TROUGH WILL
BE NEAR THE COAST AT THE START OF THE PERIOD. THIS FEATURE WILL
SLOWLY MOVE INLAND SAT INTO SUN WITH CONVECTION DEVELOPING ALONG AND
BEHIND THE BOUNDARY. COASTAL AREAS WILL BE FAVORED AS BOUNDARY IS
NOT EXPECTED TO MOVE VERY FAR INLAND DURING SAT. WEAK MID LEVEL
PATTERN AND DIFFUSE NATURE OF THE SURFACE TROUGH WILL KEEP
ACTIVITY DIURNAL IN NATURE SO COVERAGE SHOULD DECREASE WITH THE
LOSS OF HEATING SAT EVENING.
SUN SHOULD BE SIMILAR TO SAT BUT WITH ACTIVITY DEVELOPING A LITTLE
EARLIER AND A LITTLE FARTHER INLAND. VERY LITTLE WILL BE LEFT OF THE
COASTAL TROUGH AT THIS POINT BUT ITS REMAINS MAY STILL HELP
GENERATE THE FIRST ROUND OF CONVECTION SUN. SEA BREEZE WILL HELP
GET ACTIVITY GOING CLOSER TO THE COAST. WILL MAINTAIN CHC POP FOR
BOTH SAT AND SUN BUT WITH AN INCREASE SAT AND SLIGHT REDUCTION FOR
SUN. MORE CONVERGENCE ALONG THE BOUNDARY SAT SUGGEST BETTER POP
CHANCES EARLY. LIMITED CONVERGENCE AND INCREASING SUBSIDENCE AS
WEAK MID LEVEL RIDGE BUILDS SUN BOTH WORK TO SUPPRESS CONVECTION.
TEMPERATURES BELOW CLIMO FOR SAT WILL INCREASE SLIGHTLY SUN AS
HEIGHTS/THICKNESS START TO INCREASE UNDER BUILDING RIDGE AND
SOUTHERLY FLOW BECOMES ESTABLISHED. LOWS WILL BE NEAR CLIMO BOTH
NIGHTS...HELD UP BY LINGERING DEBRIS CLOUDS AND MOIST LOW LEVEL
SOUTHERLY FLOW.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 3 AM FRIDAY...PERIOD WILL BE MARKED BY A TYPICAL SUMMER
PATTERN. BERMUDA HIGH AND PIEDMONT TROUGH COMBO AT THE SURFACE WITH
WEAK RIDGING ALOFT. THIS SETUP WILL BRING PLENTY OF DEEP MOISTURE TO
THE REGION WITH PRECIPITABLE WATER VALUES APPROACHING 2 INCHES NEXT
WEEK. EXPECT CONVECTION ON BOTH THE SEA BREEZE AND PIEDMONT TROUGH
THROUGHOUT THE PERIOD. LATER IN THE WEEK STRENGTHENING 5H RIDGE
OVER THE WEST STATES WEAKENS RIDGING OVER THE SOUTHEAST. THIS
SHOULD RESULT IN AN INCREASE IN STORM COVERAGE LATE NEXT WEEK.
WILL MAINTAIN INHERITED DIURNAL CHC POP WITH AN SLIGHT INCREASE
LATE IN THE PERIOD.
TEMPERATURES WILL BE NEAR CLIMO AT THE START OF THE PERIOD BUT THEN
BEGIN A STEADY INCREASE AS SUMMER TAKES HOLD. BOTH GFS/ECMWF
INCREASE 850 TEMPS FROM 15C MON MORNING TO NEAR 20C BY THE END OF
THE PERIOD.
&&
.AVIATION /12Z FRIDAY THROUGH WEDNESDAY/...
AS OF 12Z...MOISTURE LURKING OFFSHORE WILL SLOWLY EDGE TOWARD THE
COAST THROUGH THE AFTERNOON. SOME ISOLATED/SCATTERED CONVECTION IS
EXPECTED...PERHAPS MOVING INLAND BY LATE AFTERNOON WITH A WEAK
SEABREEZE. TONIGHT DEEPER MOISTURE BEGINS TO IMPINGE THE
COAST...WITH MODERATE TO HEAVY SHOWERS EXPECTED AT THE MYRTLE BEACH
AIRPORTS AFTER MIDNIGHT...AND POTENTIALLY MAKING IT TO ILM A COUPLE
OF HOURS LATER.
SATURDAY...SCATTERED SHOWERS ARE EXPECTED THROUGH THE END OF THE
FORECAST PERIOD...WITH LBT AND FLO GETTING INTO THE ACT BY MID
MORNING. CONTINUED LIGHT NORTHEAST SFC WINDS THROUGH THE PERIOD...A
BIT MORE EASTERLY ALONG THE COAST.
EXTENDED OUTLOOK...MODERATE CHANCE OF SHOWERS THROUGH WEDNESDAY AS A
STALLED FRONT LINGERS NEAR THE COAST. BEST CHANCE FOR PRECIP WILL BE
IN THE AFTERNOON...WITH LOCAL MVFR/IFR CONDITIONS POSSIBLE.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 100 PM FRIDAY...THE WORST OF THE NORTHEAST WINDS APPEAR TO BE
OVER AS EXPECTED. BUOY AND BEACHFRONT WEATHER STATIONS ARE SHOWING
WINDS 3-5 KNOTS LESS THAN EARLIER THIS MORNING. THIS IMPROVING TREND
SHOULD CONTINUE INTO THE AFTERNOON AS THE OFFSHORE FRONT DRAWS A
LITTLER NEARER TO THE COASTAL WATERS. PREVIOUS DISCUSSION FROM 1030
AM FOLLOWS...
YESTERDAY`S STALLED FRONT IS NOW BEGINNING TO PUSH WESTWARD TOWARD
THE COAST. SATELLITE AND MODEL ANALYSIS SHOWS THE BOUNDARY IS ABOUT
50 MILES SOUTHEAST OF BALD HEAD ISLAND...OR APPROXIMATELY 20 MILES
SOUTHEAST OF THE FRYING PAN SHOALS BUOY WHERE INCIDENTALLY A
NORTHEAST WIND CONTINUES. THE BOUNDARY WILL MAKE ONLY A LITTLE
PROGRESS WESTWARD THROUGH THE AFTERNOON HOURS WITH A MAINLY
NORTHEAST WIND EXPECTED WITHIN THE COASTAL WATERS. WIND SPEEDS ARE
STRONGEST THIS MORNING...A SOLID 15 KNOTS WITH 20 KNOT GUSTS STILL
BEING OBSERVED AT THE FRYING PAN SHOALS BUOY AND ON BALD HEAD
ISLAND. THE PRESSURE GRADIENT WILL WEAKEN THIS AFTERNOON WITH WIND
SPEEDS DIMINISHING TO 10-15 KNOTS. SEAS REMAIN IN THE 3-5 FT RANGE
WITH A BROAD SPECTRUM OF WAVE PERIODS FROM 4-10 SECONDS OBSERVED ON
SPECTRAL WAVE OUTPUT FROM THE FRYING PAN SHOALS BUOY. THE WAVEWATCH
MODEL SHOWS A DOMINANT WAVE PERIOD AROUND 6 SECONDS TODAY WITH A
NOTABLE WAVE TRAIN AT 9 SECONDS PERIOD TOO.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 3 AM FRIDAY...ILL DEFINED GRADIENT DURING THE PERIOD WILL
KEEP WIND SPEEDS UNDER 10 KT THROUGH SUN NIGHT. NORTHEAST TO EAST
FLOW SAT MORNING WILL BECOME EAST TO SOUTHEAST DURING THE DAY AS
WEAK TROUGH MOVES ONSHORE. ELONGATED SURFACE RIDGE OFF THE MID
ATLANTIC COAST SLIDES SOUTH SAT NIGHT INTO SUN WITH LIGHT WINDS
GRADUALLY VEERING FROM EAST-SOUTHEAST TO SOUTH-SOUTHEAST. SEAS
WILL RUN 2 TO 3 FT MAINLY AS WEAK EASTERLY SWELL.
LONG TERM /MONDAY THROUGH TUESDAY/...
AS OF 3 AM FRIDAY...SOUTHWEST FLOW WILL PERSIST THROUGH THE
PERIOD WITH BERMUDA HIGH PRESSURE AND PIEDMONT TROUGH BEING THE
MAIN SURFACE FEATURES. LITTLE CHANGE TO THE GRADIENT THROUGH THE
PERIOD WILL KEEP WINDS 10 TO 15 KT WITH SLIGHTLY HIGHER SPEEDS
EACH AFTERNOON AS TROUGH BECOMES MORE DEFINED. SEAS RUN 2 TO 4 FT
WITH SOUTHERLY SWELL BECOMING MORE NOTICEABLE.
&&
.TIDES/COASTAL FLOODING...
AS OF 3 AM FRIDAY...TIDAL RANGES ARE EXPANDING WITH THE ARRIVAL OF
THE FULL MOON ON SUNDAY. THE DOWNTOWN WILMINGTON TIDE GAUGE DID
BRIEFLY EXCEED ITS MINOR COASTAL FLOOD THRESHOLD LAST EVE.
HOWEVER...THE DEPARTURES MAY NOT BE AS SIGNIFICANT TONIGHT GIVEN THE
ONSHORE FLOW WILL BE WEAKER. WILL NOT ISSUE ANY COASTAL FLOOD
ADVISORIES AT THIS TIME. HOWEVER...WE WILL CONTINUE TO CLOSELY
MONITOR TRENDS. ALTHOUGH WATER LEVELS WILL BE ELEVATED DURING BOTH
HIGH TIDE CYCLES INTO EARLY NEXT WEEK...BOTH ALONG THE CAPE FEAR
RIVER AND THE COAST...THE HIGHEST OF THE PREDICTED TIDES IS THE PM
TIDE. HIGH TIDE TONIGHT IS 630 PM ALONG THE IMMEDIATE COAST AND NEAR
830 PM ALONG THE CAPE FEAR RIVER IN DOWNTOWN WILMINGTON.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...III
LONG TERM...III
AVIATION...43
TIDES/COASTAL FLOODING...RJD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
139 AM EDT FRI JUN 21 2013
.SYNOPSIS...
TODAY IS THE OFFICIAL START OF SUMMER. HIGH PRESSURE WILL RETREAT AS
A LINGERING FRONT OFFSHORE NUDGES BACK TO THE WEST THROUGH THE
WEEKEND...BRINGING AN INCREASING RISK FOR SHOWERS AND THUNDERSTORMS.
TYPICAL SUMMERTIME WEATHER IS EXPECTED NEXT WEEK WITH BERMUDA HIGH
PRESSURE AND THE PIEDMONT TROUGH BECOMING THE DOMINANT SURFACE
FEATURES.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AS OF 1045 PM THURSDAY...MODEL CONSENSUS CONTINUES WITH THE STALLED
FRONT OFFSHORE FROM THE CAROLINAS...DRIFTING WESTWARD TOWARD THE
CAROLINA COASTLINES OVERNIGHT. IT MAY REACH THE OUTER WATERS OF
THE COASTAL WATERS WELL AFTER DAYBREAK FRIDAY. THE STUBBORN NOSE
OF HIGH PRESSURE RIDGING SOUTHWEST FROM ITS 1030 MB CENTER...WILL
HOLD ITS GROUND OVERNIGHT INTO FRIDAY. DRIER AIR WITH DEWPOINTS IN
THE 50S ACROSS THE NORTHERN PORTIONS OF THE ILM CWA...RISING INTO
THE 60S ACROSS THE SOUTHERN PORTIONS OF THE ILM CWA. DEWPOINTS WILL
ONLY MODERATE SOME TONIGHT AS THE SFC HIGH CONTINUES TO WEDGE
SOUTHWEST ACROSS THE AREA. MAINLY CIRRUS TO AFFECT THE ILM CWA
TONIGHT...WITH MID TO HIGH LEVEL CLOUDINESS ASSOCIATED WITH THE
STALLED FRONT POSSIBLY REACHING THE COASTAL COUNTIES DURING THE
PRE-DAWN FRI HOURS. PCPN ASSOCIATED WITH THE ADVANCING WESTWARD
MOVING FRONT...WILL BE HIGHLIGHTED IN THE LOW CHANCE CATEGORY BY 6
AM FRI...MAINLY OVER THE ADJACENT COASTAL WATERS. FEW TWEAKS TO
THE CURRENT MIN TEMP FORECAST CLOSER TO THE COAST...OTHERWISE
REMAINDER OF THE TEMP FCST LOOKS AOK.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
AS OF 300 PM THURSDAY...DRY HIGH PRESSURE NOSING IN FROM THE
NORTHEAST INTO THE CENTRAL CAROLINAS WILL GET PUSHED FARTHER
INLAND AS THE LINGERING FRONT TO OUR SOUTHEAST MOVES BACK TOWARD
THE COAST. A VERY TIGHT GRADIENT WILL EXIST BETWEEN THE VERY DRY
AIR TO THE NORTHWEST AND THE MOISTURE LADEN AIR MASS TO THE
SOUTHEAST. PCP WATER VALUES WILL BE DOWN TO A HALF INCH IN CENTRAL
NC BUT WILL BE UP TO 2 INCHES ALONG COASTAL SC. THIS LINGERING
BOUNDARY WILL RETURN TO THE COAST AS IT GRADUALLY WEAKENS THROUGH
THE WEEKEND. INITIALLY IT WILL SPREAD CLOUDS OVER THE COASTAL
AREAS BUT THROUGH THE DAY ON FRI THE CLOUDS WILL SPREAD FURTHER
INLAND. LOOKS LIKE THE BEST MOISTURE RETURN AND CONVERGENCE WILL
BE CLOSER TO THE SC COAST ON FRI AS WINDS SHIFT TO THE E-SE
THROUGH DAY. BY SATURDAY THE BOUNDARY WILL MOVE FAR ENOUGH INLAND
WITH WINDS COMING AROUND TO THE EAST TO SOUTHEAST OVER MOST OF
AREA WITH DEEPER MOISTURE MAKING ITS WAY IN.
DEEP MOISTURE AND WEAK STEERING FLOW COULD POSE A FLOOD THREAT BUT
MOST MODEL QPF HAS BACKED OFF OF TOTAL AMOUNTS. SOUNDINGS AND
MOISTURE PROFILES SUGGEST A HUGE INCREASE IN MOISTURE THROUGH THE
MID TO UPPER LAYERS ESPECIALLY AND MAY SEE MUCH MORE IN THE WAY
OF CLOUDS THAN PCP. FLOODING MAY BE VERY LOCALIZED.
TEMPERATURES WILL REMAIN BELOW CLIMO THROUGH THE PERIOD WITH
CLOUDS AND PCP HOLDING THEM DOWN ALONG THE COAST AND SLIGHTLY
COOLER AIR MASS INLAND. MAX TEMPS WILL REMAIN IN THE LOW TO MID
80S MOST PLACES. LOWS WILL RUN A LITTLE CLOSER TO CLIMO...THOUGH
STILL UNDER.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 300 PM THURSDAY...BIGGEST QUESTION MARK DURING THE LONG TERM
CONTINUES TO BE HOW A DECAYING COASTAL TROUGH/REMNANT FRONT...WHICH
WILL LIFT BACK NORTH ACROSS THE AREA SUNDAY...WILL IMPACT THE AREA.
WHILE ECMWF CONTINUES TO BE THE DRIEST OF THE MODELS...IT HAS
TRENDED WETTER...AND IT NOW LOOKS LIKE SUNDAY WILL BE PRETTY CLOUDY
WITH SHOWERS/TSTMS...ESPECIALLY THE EASTERN HALF OF THE AREA. STILL
MUCH UNCERTAINTY THOUGH SINCE THE BOUNDARY IS WEAKENING...AND THE
ANTECEDENT AIRMASS LOOKS QUITE DRY. BUT WILL INCREASE POP TO
MEDIUM-CHC AS THE BOUNDARY LIFTS NORTH INTO AN AIRMASS WITH PWATS
RISING TO 1.75 INCHES.
BEHIND THIS BOUNDARY...MORE TYPICAL SUMMERTIME PATTERN SETS UP FOR
THE REMAINDER OF THE EXTENDED WITH BERMUDA HIGH ANCHORING OVER THE
WESTERN ATLANTIC OCEAN AND MID-LEVEL RIDGING BULGING ACROSS THE
SOUTHERN TIER. THIS WILL PUMP CONSIDERABLE MOISTURE INTO THE REGION
AND WILL SUPPORT AT LEAST SCATTERED SEA BREEZE AND PIEDMONT TROUGH
CONVECTION EACH DAY NEXT WEEK. BY WED/THU...LARGE UPPER RIDGE
EXPANDS ACROSS THE SOUTHWEST...WEAKENING THE RIDGE IN THE EAST...AND
MORE WIDESPREAD CONVECTION IS POSSIBLE DURING THAT TIME.
TEMPS WILL RISE SLOWLY THROUGH THE PERIOD...WITH SUNDAY BEING THE
COOLEST DAY WITH TEMPS SLIGHTLY BELOW CLIMO. A WARMING TREND
COMMENCES THEREAFTER AS TEMPS RISE TO ABOVE NORMAL MUCH OF NEXT
WEEK.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 06Z...EXPECT VFR TO CONTINUE THROUGH THE VALID PERIOD WITH THE
EXCEPTION OF POTENTIAL MVFR CEILINGS 09-13Z AT THE COAST.
VFR CONTINUES ACROSS THE AREA WITH NE WINDS AOB 8 KTS. GIVEN LATEST
ANALYSIS WILL CONTINUE TO CARRY THE POTENTIAL FOR MORNING STRATUS
ALONG THE COAST CREATING MVFR/POSSIBLE BRIEF IFR. OTHERWISE VFR WILL
PREVAIL WITH INCREASING CLOUDS THROUGHOUT THE DAY AS A FRONT OFF THE
CAROLINA COAST BEGINS TO MOVE WEST. ISOLATED TO SCATTERED SHOWERS/
THUNDERSTORMS THROUGHOUT THE DAY...ESPECIALLY ALONG THE COAST...WITH
EAST- NORTHEAST WINDS AOB 10 KTS. INTO THE EVENING HOURS...VFR WILL
PREVAIL WITH BKN/OVC SKIES AND LIGHT NORTHEAST WINDS.
EXTENDED OUTLOOK...MODERATE CHANCE OF SHOWERS THROUGH TUESDAY AS A
STALLED FRONT LINGERS NEAR THE COAST. BEST CHANCE FOR PRECIP WILL BE
IN THE AFTERNOON...WITH LOCAL MVFR/IFR CONDITIONS POSSIBLE.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1045 PM THURSDAY...WEDGE OF HIGH PRESSURE ACROSS THE INLAND
CAROLINAS...AND THE STALLED FRONT OFFSHORE AND PARALLEL TO THE
CAROLINA COASTLINES...WILL COMBINE TO PRODUCE A NE-E WIND 15 TO 20
KT FOR MUCH OF THE OVERNIGHT PERIOD...POSSIBLY DIMINISHING TO
AROUND 15 KT BY DAYBREAK FRIDAY. DURING THE PRE-DAWN FRI
HOURS...THE STALLED FRONT WILL BEGIN TO ADVANCE WESTWARD AND
POSSIBLY REACH THE OUTER WATERS OF THE COASTAL WATERS WELL AFTER
DAYBREAK FRI. LATEST HRRR SFC WIND OUTPUT FOLLOWED CLOSELY.
FIVE TO 6 SECOND AVERAGE PERIOD WIND DRIVEN WAVES WILL DOMINATE
SIGNIFICANT SEAS. EXPECT 3 TO 5 FOOT SIG SEA HEIGHTS FOR THE
REMAINDER OF THE OVERNIGHT...WITH 2 TO 4 FT SOUTH OF CAPE FEAR TO
MYRTLE BEACH WHICH LIES IN A PROTECTIVE SHADOW RESULTING FROM NE-E
WIND DRIVEN WAVES MOVING ACROSS FRYING PAN SHOALS. WILL CONTINUE
THE BORDERLINE SCEC THROUGH 6 AM.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 300 PM THURSDAY...NORTHEAST WINDS WILL DIMINISH TO UNDER 15
KTS FRI AS LINGERING SURFACE BOUNDARY EAST TO SOUTHEAST OF THE
WATERS MOVES CLOSER AND SURFACE HIGH RETREATS A LITTLE FARTHER
INLAND. AS WINDS LIGHTEN THEY WILL VEER AROUND BECOMING MORE
EASTERLY AND EVENTUALLY SOUTHEAST AS BOUNDARY SHIFTS CLOSER TO THE
COAST. ONCE THE WEAKENING FRONT/TROUGH MOVES INLAND BY SATURDAY
THE WINDS WILL BECOME MORE SOUTHEASTERLY. EXPECT A SPIKE IN WINDS
AND A GREATER E-SE FLOW CLOSE TO THE SHORE EACH AFTERNOON. SEAS 3
TO 4 FT FRI DECREASE TO 2 TO 3 FT ON SAT AND UNDER 3 FT SAT NIGHT
AS WINDS LIGHTEN WITH A SLIGHTLY LONGER PERIOD UP TO 10 SEC
EAST-SOUTHEASTERLY SWELL.
LONG TERM /SUNDAY THROUGH TUESDAY/...
AS OF 300 PM THURSDAY...LIGHT SE WINDS LESS THAN 10 KTS SUNDAY WILL
GRADUALLY VEER TO THE SOUTHWEST BY MONDAY AND PERSIST THROUGH THE
REMAINDER OF THE PERIOD AS BERMUDA HIGH PRESSURE ANCHORS OFFSHORE.
WHILE WIND SPEEDS WILL INCREASE AS THEY TURN TO THE SW...THEY WILL
REMAIN ONLY 10-15 KTS MONDAY AND TUESDAY. WHILE A WEAK WIND WAVE
CONTRIBUTION WILL EXIST WITHIN THE WAVE SPECTRUM...SEAS BECOME
INCREASINGLY SWELL-DOMINATED THROUGH THE PERIOD THANKS TO THE
PERSISTENT FETCH AROUND BERMUDA HIGH. WAVE AMPLITUDES WILL BE 1-3 FT
SUNDAY...GROWING TO 2-4 FT MONDAY AND TUESDAY.
&&
.TIDES/COASTAL FLOODING...
AS OF 300 PM THURSDAY...TIDAL RANGES ARE EXPANDING AS THE FULL MOON
APPROACHES THIS WEEKEND. SEVERAL HIGH TIDES THIS WEEKEND MAY
REACH MINOR COASTAL FLOODING CRITERIA ALONG THE CAPE FEAR RIVER AT
DOWNTOWN WILMINGTON. THIS IS NOT EXPECTED TO BE A MAJOR EVENT...BUT
ANYTIME THE RIVER RISES TO MORE THAN 5.50 FEET ABOVE MLLW PROBLEMS
DEVELOP ALONG BATTLESHIP ROAD AND NEAR THE U.S.S. NORTH CAROLINA
BATTLESHIP MEMORIAL. THIS EVENING`S HIGH TIDE SHOULD FALL SHORT OF
5.50 FEET...BUT HIGH TIDES SATURDAY AND SUNDAY EVENINGS HAVE MUCH
BETTER POTENTIAL TO PRODUCE MINOR FLOODING.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...DCH
SHORT TERM...RGZ
LONG TERM...JDW
AVIATION...SGL/RJD
TIDES/COASTAL FLOODING...TRA
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
712 PM CDT SAT JUN 22 2013
.UPDATE...
ISSUED AT 702 PM CDT SAT JUN 22 2013
ISSUE IS CONVECTIVE TRENDS THE NEXT 12 HOURS...AND HOW THINGS MAY
OR MAY NOT EVOLVE IS NOT CLEAR CUT THIS EVE. A WELL DEFINED WARM
FRONT EXTENDS FROM NEAR RED WING MN INTO NORTHWEST IOWA THEN INTO
CENTRAL NEBRASKA. SPC MESO ANALYSIS SHOWS 5-6K J/KG CAPES ALONG
THIS BOUNDARY AND A 40 KT 850 JET TONIGHT OVER THIS BOUNDARY. SO
ALL THINGS WOULD INDICATE JUST NORTH OF THIS FEATURE WILL BE
ACTIVE FROM NRN NEBRASKA/SRN SD INTO SRN MN. ALSO PWATS HIGHEST
THERE WITH 1.70 INCHES AND WPC STATEMENTS INDICATING HEAVY RAIN
THREAT THERE.
SECOND HAVE A WELL DEFINED UPPER SHORT WAVE MOVING THRU NRN
WYOMING AND THIS WILL MOVE NORTHEAST THRU WRN ND INTO WRN MANITOBA
INTO SUNDAY. MOST MODELS HAVE THIS PLAN WITH GENERAL AREA OF RAIN-
STORMS FROM WRN ND INTO WRN MANITOBA THRU 18Z SUN. THAT LEAVES ERN
ND/NW MN IN BETWEEN AGAIN. HOWEVER...UNLIKE LAST NIGHT WE DO HAVE
A SFC BOUNDARY IN PLACE FROM WEST OF PORTAGE MB TO BTWN CANDO-
RUGBY THEN TO AROUND WISHEK ND. NOW NARROW LINE OF STORMS IN
MANITOBA WITH FEATURE. THEN ONE SEVERE CELL GOT GOING ALONG LINE
AND IN MAX 2500 J/KG SFC CAPE AREA NR WISHEK ND SOUTHEAST OF
BISMARCK. NOT SURE IF THIS IS MOSTLY HEAT DRIVEN SINCE SUPPORT FOR
THIS CELL ALOFT IS NOT GREAT WITH BULK SHEAR IN WRN ND.
THEN HAVE BOW STRUCTING MOVING EAST THRU WRN SD AND IDEA IS THIS
WILL MOVE INTO NORTH CENTRAL SD THIS EVE AND HRRR DOES HAVE
SOMETHING WITH THIS INTO NE SD LATER TONIGHT THEN SWINGS SOME
PRECIP NORTHEAST INTO NRN MN AFTER 12Z. THIS LEAVES NRN VALLEY IN
GENERALLY THE LEAST THREAT ZONE.
UPDATED POPS TO MATCH A BIT OF THE ABOVE REASONING.
WILL KEEP FFA AS IS THRU 12Z BUT INDICATIONS HEAVY RAIN THREAT NOT
TERRIBLY HIGH AS MAIN DEEPER MOISTURE LOCKED ALONG WARM FRONT TO
OUR SOUTH.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 319 PM CDT SAT JUN 22 2013
MAIN CONCERN CONTINUES TO BE CONVECTION CHANCES THROUGH THE
PERIOD.
THE MAIN UPPER TROUGH IS STILL SEEN MOVING THROUGH THE NORTHERN
ROCKIES BUT IS FINALLY STARTING TO SLOWLY KICK OFF TO THE EAST.
SEVERAL LEAD SHORTWAVES ARE EVIDENT ON WV LOOP IN THE
SOUTHWESTERLY FLOW AHEAD OF THE MAIN TROUGH. ONE SIGNIFICANT
SHORTWAVE IS OVER THE CENTRAL ROCKIES CURRENTLY SETTING OFF STORMS
IN CO AND WY. THIS SHORTWAVE WILL MOVE INTO PARTS OF WESTERN NORTH
DAKOTA AND COULD POSSIBLY IMPACT OUR SOUTHWESTERN COUNTIES.
ANOTHER WEAK SHORTWAVE MODELS HAVE MOVING INTO CENTRAL MN OVERNIGHT.
MODEL PERFORMANCE HAS BEEN POOR LATELY AND DO NOT FEEL CONFIDENT
IN ANY ONE SOLUTION. SPC MESOANALYSIS HAS 2000 OR MORE J/KG OF
CAPE OVER OUR WESTERN COUNTIES...BUT THERE HAS BEEN NO BULK SHEAR
AND NOT MUCH IN THE WAY OF LIFT TO SET ANYTHING GOING. THINK THAT
THE REST OF THE AFTERNOON AND EVENING SHOULD BE FAIRLY DRY...WITH
THE BULK OF THE ACTIVITY HOLDING OFF UNTIL AFTER MIDNIGHT TONIGHT.
LATER ON TONIGHT THERE WILL BE BETTER CHANCES OF THE ACTIVITY TO
OUR SOUTHWEST ORGANIZING AND MOVING THROUGH. THINK SOME DAMAGING
WINDS ARE NOT OUT OF THE QUESTION WITH PRETTY GOOD DOWNDRAFT CAPE
AVAILABLE. SOME VARIATION IN THE MODELS BETWEEN WHICH GETS THE
MOST PRECIP...THE SOUTH OR THE NORTHWEST. AT THIS POINT MANY OF
THE NORTHERN COUNTIES HAVE RECEIVED NOT NEARLY AS MUCH RAINFALL AS
THE SOUTH AND IT LOOKS LIKE THE DVL TO GFK TO BJI AREA WILL BE ON
THE SHORT END AGAIN TONIGHT. THUS REMOVED THOSE COUNTIES FROM THE
FLASH FLOOD WATCH BUT WILL MAINTAIN THEM FURTHER SOUTH FOR NOW.
THE MAIN UPPER TROUGH WILL FINALLY MOVE OUT INTO THE PLAINS
TOMORROW. IT SEEMS AT THIS POINT THAT THE SFC TROUGH WILL MOVE
OVER THE CWA AT SOME POINT. THE MODELS ALSO SHOW SIGNS OF A DRIER
AND SLIGHTLY COOLER AIR COMING INTO THE AREA WITH A FRONTAL
BOUNDARY. THINK THERE COULD BE SOME THUNDERSTORM ACTIVITY ALONG
THIS BOUNDARY AS IT MOVES THROUGH OUR SOUTHEASTERN COUNTIES DURING
PEAK HEATING...AND SOME ADDITIONAL PRECIP IN THE NORTHERN
COUNTIES NEARER THE MAIN SHORTWAVE. ADJUSTED POPS ACCORDINGLY.
PRECIP SHOULD TAPER OFF SUNDAY NIGHT AS THE UPPER TROUGH FINALLY
BEGINS TO PULL NORTHEASTWARD INTO ONT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 319 PM CDT SAT JUN 22 2013
MONDAY SHOULD BE FAIRLY QUIET WITH WEST TO SOUTHWESTERLY FLOW
ALOFT. WINDS WILL SHIFT BACK TO THE SOUTH AS A TROUGH DEVELOPS
OVER THE NORTHERN ROCKIES. MODELS SHOW HINTS OF A WEAK SHORTWAVE
MOVING THROUGH MONDAY NIGHT AND BRINGING ANOTHER ROUND OF
PRECIP...ALTHOUGH THERE IS STILL SOME UNCERTAINTY AS TO EXACT
TIMING. KEPT SOME 20-40 POPS GOING FOR NOW.
MODELS INITIALIZED WELL AND IN GENERAL AGREEMENT WITH RESPECT TO
OVERALL PATTERN. OTHERWISE...MAIN CHALLENGE WILL BE UNSETTLED NATURE
OF PATTERN THRU THE EXTENDED PERIOD. MEAN UPPER RIDGE IS PROGGED
OVER THE FA WITH A SERIES OF IMPULSES MOVING THRU THE FLOW RESULTING
IN INCREASED INSTABILITY AND GREATER CHANCES FOR -SHRA/-TSRA. THE
ASSOCIATED SFC SYSTEM LOOKS TO FINALLY PUSH OUT BY DAY 6 AND WEAK
SFC RIDGING MOVES IN. THUS...EXPECTING MORE STABLE...DRIER AND A BIT
COOLER CONDITIONS THRU THE END OF THE EXTENDED PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 702 PM CDT SAT JUN 22 2013
WELL ISSUE WILL BE LATER TONIGHT INTO SUNDAY MORNING IN REGARDS TO
LOWER MVFR CIGS. LAST NIGHT HAD RAIN MOVE THRU NE SD INTO CNTRL
MN AND THEN LOW CLOUDS FORM AND MOVE NORTHWARD. WILL NOT HAVE THAT
TONIGHT AT LEAST NOT EARLY ON. THUS IDEA OF LOWER CLOUDS FORMING
OR SPREADING NORTH LATE TONIGHT-SUN AM NOT CERTAIN. DID KEEP THIS
EVE VFR BUT KEPT IDEA OF SOME MVFR CIGS LATER TONIGHT ALONG WITH
SOME SHOWERS OR THUNDER AT MOST SITES AFTER 08Z-10Z. WINDS
GENERALLY SOUTH-SOUTHEAST LESS THAN 10 KTS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...FLASH FLOOD WATCH UNTIL 7 AM CDT SUNDAY FOR NDZ014-024-028>030-
038-039-049-052-053.
MN...FLASH FLOOD WATCH UNTIL 7 AM CDT SUNDAY FOR MNZ002-003-022>024-
027>032-040.
&&
$$
UPDATE...RIDDLE
SHORT TERM...JR
LONG TERM...JR/HOPKINS
AVIATION...RIDDLE
AREA FORECAST DISCUSSION
NWS BISMARCK ND
117 PM CDT FRI JUN 21 2013
.UPDATE...
ISSUED AT 120 PM CDT FRI JUN 21 2013
MODIFIED POPS BASED ON LATEST RADAR. DAYTIME TEMPERATURES ALSO
TRENDED COOLER WITH EXTENSIVE CLOUDINESS IN PLACE. MAIN
THUNDERSTORM COMPLEX OVER SOUTH CENTRAL NORTH DAKOTA...ADVECTING
EAST AND SLIGHTLY NORTH.
UPDATE ISSUED AT 1100 AM CDT FRI JUN 21 2013
WILL ALLOW THE DENSE FOG ADVISORY TO EXPIRE AT 11 AM CDT.
VISIBILITIES CONTINUE TO IMPROVE ACROSS WEST AND CENTRAL NORTH
DAKOTA. PATCHY AREAS OF FOG MAY LINGER INTO THE AFTERNOON SOME
LOCATIONS WITH VERY HIGH BOUNDARY LAYER MOISTURE IN PLACE...WITH
SURFACE DEWPOINTS IN THE 60S TO EVEN AROUND 70F SOME LOCATIONS.
LATEST RAP (13Z AND 14Z RUNS) SEEMS TO BE DOING THE BEST SO FAR
WITH CURRENT SHOWERS AND STORMS...WEST AND SOUTH WITH THE HEAVIER
ECHOS SOUTHWEST OVER ADAMS AND HETTINGER COUNTIES.
SKIES SHOULD REMAIN MAINLY CLOUDY THROUGHOUT THE DAY ALONG WITH
CHANCES FOR SHOWERS AND THUNDERSTORMS...SOME SEVERE...WITH
NUMEROUS EMBEDDED WAVES LIFTING ACROSS THE DAKOTAS. BEST CHANCE
FOR WIDESPREAD CONVECTION WITH SEVERE WEATHER AND HEAVY RAIN WILL
BE MID/LATE AFTERNOON INTO THIS EVENING WITH PEAK HEATING AND
INSTABILITY MAXIMIZED. MODELS ARE KEYING IN ON CONVECTION FIRING
UP ACROSS SOUTH DAKOTA LIFTING NORTH AND EAST TODAY INTO THIS
EVENING...WITH A DRY/QUIET PERIOD IN THE WAKE OF THIS ACTIVITY
LATE TONIGHT. WITH RICH BOUNDARY LAYER MOISTURE REMAINING IN
PLACE...REDEVELOPMENT OF FOG AND STRATUS IS LOOKING LIKELY ONCE
SKIES TREND SCT-SKC.
UPDATE ISSUED AT 908 AM CDT FRI JUN 21 2013
MAIN UPDATE WAS TO EXTEND THE DENSE FOG ADVISORY UNTIL 11 AM CDT
WITH SEVERAL AREA OBSERVING SITES REPORTING 1/4 MILE OR LESS STILL.
UPDATE ISSUED AT 618 AM CDT FRI JUN 21 2013
UPDATE TO ISSUE DENSE FOG ADVISORY FOR PORTIONS OF THE FORECAST
AREA AS OBS/WEBCAMS/SPOTTER REPORTS INDICATING DENSE FOG COVERAGE
IS NOW SIGNIFICANT...AND WARRANTS HEADLINES. ALSO INCREASED POPS
SLIGHTLY FAR WEST PER LATEST RADAR TRENDS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 402 AM CDT FRI JUN 21 2013
THE HIGHLIGHT OF THE SHORT TERM IS SEVERE CONVECTIVE POTENTIAL
THIS AFTERNOON THROUGH TONIGHT. THE MAIN QUESTION IS HOW QUICKLY
CAPPING WILL BE ERODED TO ALLOW FOR SURFACE BASED CONVECTION THIS
AFTERNOON. THE 00 UTC NAM/GFS BUFR SOUNDINGS DO VARY SIGNIFICANTLY
IN REGARDS TO THE STRENGTH OF THIS CAPPING...WITH THE GFS HOLDING
A STRONG CAP THROUGH THE AFTERNOON...WITH THE NAM SHOWING LITTLE
CONVECTIVE INHIBITION BY 18 UTC. THE 03 UTC SREF SOUNDINGS DO SHOW
WEAKER CAPPING THAN THE GFS...HOWEVER...THE 00 UTC 4 KM WRF HAS
LITTLE AFTERNOON CONVECTION ACROSS THE AREA. THUS...DID LIMIT POPS
TO SLIGHT CHANCE OR CHANCE PRIOR TO 00 UTC. SHOULD CAPPING BE
ERODED...ML CAPE VALUES OF 2500-3500 J/KG WITH 50 KTS OF DEEP
LAYER SHEAR ARE AVAILABLE...WITH VERY LARGE HAIL POSSIBLE GIVEN
-10 TO -30 C CAPE VALUES NEAR 1000 J/KG.
THE BETTER CHANCES FOR THUNDERSTORMS ARE THIS EVENING AND TONIGHT
WITH A POTENTIAL MCS PROPAGATING OUT OF SOUTH DAKOTA WITH THE
ARRIVAL OF GREATER UPPER LEVEL FORCING. IN ADDITION TO LARGE HAIL
AND DAMAGING WINDS...HEAVY RAINFALL WILL BECOME AN INCREASING
THREAT...ESPECIALLY FOR THOSE AREAS IMPACTED BY HEAVY RAINFALL
WEDNESDAY AND THURSDAY...WITH PWATS 1.50 INCHES AND K INDEX VALUES
OF 35-40 C.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 402 AM CDT FRI JUN 21 2013
THE MAIN FORECAST CONCERNS DURING THE LONG TERM PERIOD ARE THE
POTENTIAL FOR CONTINUED HEAVY RAIN AND FLASH FLOODING OVER THE
WEEKEND. MODEL CONSENSUS INDICATES AN UPPER TROUGH MOVING INTO THE
NORTHERN PLAINS SATURDAY AND SATURDAY NIGHT. BROAD SYNOPTIC LIFT
WILL SUPPORT WIDESPREAD SHOWERS AND THUNDERSTORMS...ESPECIALLY LATER
IN THE DAY. THE JAMES RIVER VALLEY WILL AGAIN BE UNDER THE GUN FOR
ADDITIONAL FLOODING...ALONG WITH ISOLATED SEVERE STORMS. BY
SUNDAY...THE UPPER LOW WILL LIFT NORTH WITH THE FOCUS OF SHOWERS AND
STORMS ACROSS THE NORTHERN COUNTIES...WHICH WILL DIMINISH SUNDAY
NIGHT. SOUTHWEST FLOW WILL PERSIST MONDAY AND TUESDAY WITH RAIN
EXPECTED TO BE MORE SCATTERED ACROSS THE STATE. BY THURSDAY...AN
UPPER RIDGE WILL BEGIN TO SPREAD INTO WESTERN NORTH DAKOTA. CLOUDS
WILL KEEP AFTERNOON TEMPS DOWN MAINLY IN THE 70S OVER THE
WEEKEND...FOLLOWED BY NEAR TO SLIGHTLY ABOVE NORMAL TEMPS IN THE LOW
80S BY EARLY TO MID WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 120 PM CDT FRI JUN 21 2013
STRATUS WILL CONTINUE ACROSS PORTIONS OF WESTERN AND CENTRAL
NORTH DAKOTA GIVEN THE HUMID AIRMASS IN PLACE...WITH MVFR
CONDITIONS EXPECTED AT TIMES. THUNDERSTORMS ARE POSSIBLE THIS
AFTERNOON INTO THIS EVENING. STRATUS AND FOG EXPECTED TO REDEVELOP
OVERNIGHT INTO SATURDAY MORNING.
&&
.HYDROLOGY...
ISSUED AT 120 PM CDT FRI JUN 21 2013
EXPANDED THE FLASH FLOOD WATCH INTO EMMONS COUNTY GIVEN THE
SIGNIFICANT RAINFALL THAT OCCURRED THURSDAY EVENING. MULTIPLE
ROUNDS OF STRONG TO SEVERE THUNDERSTORMS ARE EXPECTED
FRIDAY 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 EXPECTED
FRIDAY EVENING AND NIGHT...AND 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...NH
LONG TERM...RP KINNEY
HYDROLOGY...AYD/NH
AVIATION...NH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1103 AM CDT FRI JUN 21 2013
.UPDATE...
ISSUED AT 1100 AM CDT FRI JUN 21 2013
WILL ALLOW THE DENSE FOG ADVISORY TO EXPIRE AT 11 AM CDT.
VISIBILITIES CONTINUE TO IMPROVE ACROSS WEST AND CENTRAL NORTH
DAKOTA. PATCHY AREAS OF FOG MAY LINGER INTO THE AFTERNOON SOME
LOCATIONS WITH VERY HIGH BOUNDARY LAYER MOISTURE IN PLACE...WITH
SURFACE DEWPOINTS IN THE 60S TO EVEN AROUND 70F SOME LOCATIONS.
LATEST RAP (13Z AND 14Z RUNS) SEEMS TO BE DOING THE BEST SO FAR
WITH CURRENT SHOWERS AND STORMS...WEST AND SOUTH WITH THE HEAVIER
ECHOS SOUTHWEST OVER ADAMS AND HETTINGER COUNTIES.
SKIES SHOULD REMAIN MAINLY CLOUDY THROUGHOUT THE DAY ALONG WITH
CHANCES FOR SHOWERS AND THUNDERSTORMS...SOME SEVERE...WITH
NUMEROUS EMBEDDED WAVES LIFTING ACROSS THE DAKOTAS. BEST CHANCE
FOR WIDESPREAD CONVECTION WITH SEVERE WEATHER AND HEAVY RAIN WILL
BE MID/LATE AFTERNOON INTO THIS EVENING WITH PEAK HEATING AND
INSTABILITY MAXIMIZED. MODELS ARE KEYING IN ON CONVECTION FIRING
UP ACROSS SOUTH DAKOTA LIFTING NORTH AND EAST TODAY INTO THIS
EVENING...WITH A DRY/QUIET PERIOD IN THE WAKE OF THIS ACTIVITY
LATE TONIGHT. WITH RICH BOUNDARY LAYER MOISTURE REMAINING IN
PLACE...REDEVELOPMENT OF FOG AND STRATUS IS LOOKING LIKELY ONCE
SKIES TREND SCT-SKC.
UPDATE ISSUED AT 908 AM CDT FRI JUN 21 2013
MAIN UPDATE WAS TO EXTEND THE DENSE FOG ADVISORY UNTIL 11 AM CDT
WITH SEVERAL AREA OBSERVING SITES REPORTING 1/4 MILE OR LESS STILL.
UPDATE ISSUED AT 618 AM CDT FRI JUN 21 2013
UPDATE TO ISSUE DENSE FOG ADVISORY FOR PORTIONS OF THE FORECAST
AREA AS OBS/WEBCAMS/SPOTTER REPORTS INDICATING DENSE FOG COVERAGE
IS NOW SIGNIFICANT...AND WARRANTS HEADLINES. ALSO INCREASED POPS
SLIGHTLY FAR WEST PER LATEST RADAR TRENDS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 402 AM CDT FRI JUN 21 2013
THE HIGHLIGHT OF THE SHORT TERM IS SEVERE CONVECTIVE POTENTIAL
THIS AFTERNOON THROUGH TONIGHT. THE MAIN QUESTION IS HOW QUICKLY
CAPPING WILL BE ERODED TO ALLOW FOR SURFACE BASED CONVECTION THIS
AFTERNOON. THE 00 UTC NAM/GFS BUFR SOUNDINGS DO VARY SIGNIFICANTLY
IN REGARDS TO THE STRENGTH OF THIS CAPPING...WITH THE GFS HOLDING
A STRONG CAP THROUGH THE AFTERNOON...WITH THE NAM SHOWING LITTLE
CONVECTIVE INHIBITION BY 18 UTC. THE 03 UTC SREF SOUNDINGS DO SHOW
WEAKER CAPPING THAN THE GFS...HOWEVER...THE 00 UTC 4 KM WRF HAS
LITTLE AFTERNOON CONVECTION ACROSS THE AREA. THUS...DID LIMIT POPS
TO SLIGHT CHANCE OR CHANCE PRIOR TO 00 UTC. SHOULD CAPPING BE
ERODED...ML CAPE VALUES OF 2500-3500 J/KG WITH 50 KTS OF DEEP
LAYER SHEAR ARE AVAILABLE...WITH VERY LARGE HAIL POSSIBLE GIVEN
-10 TO -30 C CAPE VALUES NEAR 1000 J/KG.
THE BETTER CHANCES FOR THUNDERSTORMS ARE THIS EVENING AND TONIGHT
WITH A POTENTIAL MCS PROPAGATING OUT OF SOUTH DAKOTA WITH THE
ARRIVAL OF GREATER UPPER LEVEL FORCING. IN ADDITION TO LARGE HAIL
AND DAMAGING WINDS...HEAVY RAINFALL WILL BECOME AN INCREASING
THREAT...ESPECIALLY FOR THOSE AREAS IMPACTED BY HEAVY RAINFALL
WEDNESDAY AND THURSDAY...WITH PWATS 1.50 INCHES AND K INDEX VALUES
OF 35-40 C.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 402 AM CDT FRI JUN 21 2013
THE MAIN FORECAST CONCERNS DURING THE LONG TERM PERIOD ARE THE
POTENTIAL FOR CONTINUED HEAVY RAIN AND FLASH FLOODING OVER THE
WEEKEND. MODEL CONSENSUS INDICATES AN UPPER TROUGH MOVING INTO THE
NORTHERN PLAINS SATURDAY AND SATURDAY NIGHT. BROAD SYNOPTIC LIFT
WILL SUPPORT WIDESPREAD SHOWERS AND THUNDERSTORMS...ESPECIALLY LATER
IN THE DAY. THE JAMES RIVER VALLEY WILL AGAIN BE UNDER THE GUN FOR
ADDITIONAL FLOODING...ALONG WITH ISOLATED SEVERE STORMS. BY
SUNDAY...THE UPPER LOW WILL LIFT NORTH WITH THE FOCUS OF SHOWERS AND
STORMS ACROSS THE NORTHERN COUNTIES...WHICH WILL DIMINISH SUNDAY
NIGHT. SOUTHWEST FLOW WILL PERSIST MONDAY AND TUESDAY WITH RAIN
EXPECTED TO BE MORE SCATTERED ACROSS THE STATE. BY THURSDAY...AN
UPPER RIDGE WILL BEGIN TO SPREAD INTO WESTERN NORTH DAKOTA. CLOUDS
WILL KEEP AFTERNOON TEMPS DOWN MAINLY IN THE 70S OVER THE
WEEKEND...FOLLOWED BY NEAR TO SLIGHTLY ABOVE NORMAL TEMPS IN THE LOW
80S BY EARLY TO MID WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1100 AM CDT FRI JUN 21 2013
PATCHY FOG AND STRATUS WILL CONTINUE ACROSS MUCH OF WESTERN AND
CENTRAL NORTH DAKOTA GIVEN THE HUMID AIRMASS IN PLACE...WITH MVFR
TO IFR CONDITIONS EXPECTED AT TIMES. ISOLATED THUNDERSTORMS ARE
POSSIBLE THIS AFTERNOON...WITH A GREATER CHANCE FOR THUNDERSTORMS
AFTER 22 UTC FRIDAY AFTERNOON MOVING FROM SOUTH TO NORTH THROUGH
FRIDAY EVENING.
&&
.HYDROLOGY...
ISSUED AT 402 AM CDT FRI JUN 21 2013
EXPANDED THE FLASH FLOOD WATCH INTO EMMONS COUNTY GIVEN THE
SIGNIFICANT RAINFALL THAT OCCURRED THURSDAY EVENING. MULTIPLE
ROUNDS OF STRONG TO SEVERE THUNDERSTORMS ARE EXPECTED
FRIDAY 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 EXPECTED
FRIDAY EVENING AND NIGHT...AND 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...NH
LONG TERM...RP KINNEY
AVIATION...NH
AREA FORECAST DISCUSSION
NWS NORMAN OK
1221 PM CDT FRI JUN 21 2013
.DISCUSSION...
REFER TO THE 18Z AVIATION FORECAST BELOW...
&&
.AVIATION...
EXPECT MAINLY VFR CONDITIONS WITH GUSTY SOUTH WINDS TO PREVAIL
THROUGH THE TAF PERIOD. VERY ISOLATED SHRA AND OR TSRA MAY DEVELOP
AT TERMINALS ACROSS SOUTHWEST OKLAHOMA AND WESTERN NORTH TEXAS.
THESE WILL LARGELY BE DRIVEN BY DAYTIME HEATING...AND SHOULD
DIMINISH AROUND SUNSET. STRONGER STORMS WILL BE CAPABLE OF STRONG
AND GUSTY WINDS...BUT OVERALL IMPACTS SHOULD REMAIN MINOR.
&&
.PREV DISCUSSION... /ISSUED 1036 AM CDT FRI JUN 21 2013/
DISCUSSION...
WEAK ECHOES OVER THE PANHANDLES CONTINUE ON RADARS...BUT THERE IS
LITTLE OR NO ACTUAL PRECIPITATION HITTING THE GROUND...AND
EASTWARD PROGRESS HAS BEEN VERY SLOW. OUR EXISTING 10-15 PERCENT
POPS IN FAR NORTHWEST OKLAHOMA ARE PROBABLY A BIT OPTIMISTIC...BUT
DO SEEM REASONABLE AT THIS POINT.
SHORT-RANGE MODELS STILL SHOW ISOLATED OR SCATTERED CONVECTION
DEVELOPING THIS AFTERNOON OVER SOUTHWEST OKLAHOMA. THE EXISTING
POPS AGAIN LOOK REASONABLE FOR NOW. AS MENTIONED PREVIOUSLY...ANY
STORMS THAT DEVELOP IN THIS ENVIRONMENT WILL BE PULSE
STORMS...WITH RAPID DEVELOPMENT...SHORT DURATION...AND THE
POTENTIAL FOR STRONG WINDS AND HEAVY RAIN.
OTHERWISE...TODAY WILL BE ANOTHER WARM...HUMID...AND BREEZY DAY
ACROSS OKLAHOMA AND NORTH TEXAS. NO CHANGES TO THE CURRENT
FORECAST ARE PLANNED FOR THIS MORNING.
PREV DISCUSSION... /ISSUED 658 AM CDT FRI JUN 21 2013/
UPDATE...
REDUCED RAIN CHANCES THIS MORNING ACROSS NORTHWEST OKLAHOMA. ADDED
10 PERCENT ISOLATED MENTION ACROSS LOCATIONS SOUTHWEST OF A ENID
TO STILLWATER LINE THIS AFTERNOON.
DISCUSSION...
CONVECTION OVER NORTHWEST OKLAHOMA HAS DISSIPATED THIS
MORNING...BUT MAY REDEVELOP OVER THE NEXT FEW HOURS.
LATEST HRRR RUNS HAVE BEEN CONSISTENT IN DEVELOPING A
FEW STORMS NEAR A VERNON TO LAWTON TO OKLAHOMA CITY LINE
BETWEEN 1 AND 5 PM THIS AFTERNOON. THUS...ADDED A 10 PERCENT
ISOLATED MENTION IN THESE LOCATIONS. IF THESE STORMS DEVELOP...
THEY COULD BE STRONG WITH GUSTY WINDS AND LOCALLY HEAVY RAINFALL
AS THEY WOULD BE SLOW MOVERS AND PULSE IN NATURE.
PRODUCTS HAVE BEEN UPDATED.
MBS
PREV DISCUSSION... /ISSUED 622 AM CDT FRI JUN 21 2013/
DISCUSSION...
AVIATION DISCUSSION FOR THE 12Z TAFS IS BELOW.
AVIATION...
VFR CONDITIONS ARE EXPECTED TO CONTINUE.
SOUTH WINDS WILL INCREASE AND BECOME GUSTY AT ALL SITES
BY 15Z...THEN BE SLOW TO DIMINISH AFTER 01Z ACROSS
WESTERN OKLAHOMA.
MVFR CEILINGS SHOULD STAY JUST SOUTH OF KSPS-KMLC
AND DISSIPATE BY 18Z.
CHANCES FOR TSRA AND NON CONVECTIVE LOW LEVEL WIND SHEAR
APPEAR TO BE TOO LOW TO MENTION.
MBS
PREV DISCUSSION... /ISSUED 357 AM CDT FRI JUN 21 2013/
DISCUSSION...
HOT AND MAINLY RAINFREE WEATHER WILL BE THE MAIN
STORY OVER THE NEXT SEVERAL DAYS.
THIS MORNING...A FEW HIGH BASED THUNDERSTORMS WILL
CONTINUE OVER FAR NORTHWEST OKLAHOMA...MAINLY NORTHWEST
OF A CHEYENNE TO ALVA LINE. NO SEVERE STORMS ARE EXPECTED.
KEPT 10-30 PERCENT...ISOLATED TO SCATTERED COVERAGE MENTION
THIS MORNING IN THESE AREAS...THOUGH THESE STORMS MAY DISSIPATE
QUICKLY OVER THE NEXT HOUR OR TWO.
THIS AFTERNOON AND EARLY THIS EVENING...GENERALLY EXPECT ANOTHER
HOT AND DRY DAY. SOME LATEST HRRR GUIDANCE HINTED THAT ISOLATED TO
SCATTERED STORMS MAY DEVELOP NEAR A VERNON TO LAWTON TO OKLAHOMA
CITY LINE BETWEEN 1 AND 5 PM...WEAKENING TOWARDS SUNSET. THE ONLY
NOTICEABLE TRIGGER FOR LIFT WOULD BE A WEAK SHORT WAVE/POSSIBLE MCV
CURRENTLY NEAR LUBBOCK TEXAS. CHANCES OF STORMS DEVELOPING SEEM
TOO LOW TO MENTION AT THIS TIME DUE TO STRONG CAPPING...THOUGH
WILL CLOSELY MONITOR. IF STORMS DEVELOP...A FEW PULSE MICROBURSTS
WITH GUSTY WINDS AND LOCALLY HEAVY RAIN WOULD BE POSSIBLE AS THE
AIR WILL BE UNSTABLE.
LATER TONIGHT THROUGH THURSDAY...GENERALLY HOT AND RAINFREE
WEATHER WILL CONTINUE. LIKE YESTERDAY EVENING...A FEW STORMS MAY
MOVE INTO FAR WESTERN OR NORTHWESTERN OKLAHOMA EACH NIGHT...BUT
ODDS ARE GOOD THAT MOST LOCATIONS WILL STAY DRY. THINK HIGHS WILL
INCREASE SLIGHTLY EACH DAY...ESPECIALLY AS THE GROUND DRIES OUT. A
WEAK FRONT MAY MAKE IT TOWARDS THE AREA LATE WEDNESDAY INTO
THURSDAY WHICH COULD BRING A BIT HIGHER RAIN CHANCES TO THE AREA.
FOR NOW...KEPT RAIN CHANCES BELOW 20 PERCENT DURING THIS TIME
FRAME. TEMPERATURES WILL GENERALLY BE 5 TO 10 DEGREES ABOVE
AVERAGE. WEDNESDAY MAY BE THE HOTTEST DAY WITH TRIPLE DIGIT HEAT
ACROSS MUCH OF WESTERN OKLAHOMA AND WESTERN NORTH TEXAS.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 72 95 72 94 / 10 0 10 10
HOBART OK 71 100 71 99 / 10 0 10 10
WICHITA FALLS TX 72 99 72 98 / 10 0 0 0
GAGE OK 70 97 70 96 / 10 10 10 10
PONCA CITY OK 72 95 72 94 / 10 10 10 10
DURANT OK 72 94 72 93 / 0 10 0 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
23/84/84
AREA FORECAST DISCUSSION
NWS NORMAN OK
1036 AM CDT FRI JUN 21 2013
.DISCUSSION...
WEAK ECHOES OVER THE PANHANDLES CONTINUE ON RADARS...BUT THERE IS
LITTLE OR NO ACTUAL PRECIPITATION HITTING THE GROUND...AND
EASTWARD PROGRESS HAS BEEN VERY SLOW. OUR EXISTING 10-15 PERCENT
POPS IN FAR NORTHWEST OKLAHOMA ARE PROBABLY A BIT OPTIMISTIC...BUT
DO SEEM REASONABLE AT THIS POINT.
SHORT-RANGE MODELS STILL SHOW ISOLATED OR SCATTERED CONVECTION
DEVELOPING THIS AFTERNOON OVER SOUTHWEST OKLAHOMA. THE EXISTING
POPS AGAIN LOOK REASONABLE FOR NOW. AS MENTIONED PREVIOUSLY...ANY
STORMS THAT DEVELOP IN THIS ENVIRONMENT WILL BE PULSE
STORMS...WITH RAPID DEVELOPMENT...SHORT DURATION...AND THE
POTENTIAL FOR STRONG WINDS AND HEAVY RAIN.
OTHERWISE...TODAY WILL BE ANOTHER WARM...HUMID...AND BREEZY DAY
ACROSS OKLAHOMA AND NORTH TEXAS. NO CHANGES TO THE CURRENT
FORECAST ARE PLANNED FOR THIS MORNING.
&&
.PREV DISCUSSION... /ISSUED 658 AM CDT FRI JUN 21 2013/
UPDATE...
REDUCED RAIN CHANCES THIS MORNING ACROSS NORTHWEST OKLAHOMA. ADDED
10 PERCENT ISOLATED MENTION ACROSS LOCATIONS SOUTHWEST OF A ENID
TO STILLWATER LINE THIS AFTERNOON.
DISCUSSION...
CONVECTION OVER NORTHWEST OKLAHOMA HAS DISSIPATED THIS
MORNING...BUT MAY REDEVELOP OVER THE NEXT FEW HOURS.
LATEST HRRR RUNS HAVE BEEN CONSISTENT IN DEVELOPING A
FEW STORMS NEAR A VERNON TO LAWTON TO OKLAHOMA CITY LINE
BETWEEN 1 AND 5 PM THIS AFTERNOON. THUS...ADDED A 10 PERCENT
ISOLATED MENTION IN THESE LOCATIONS. IF THESE STORMS DEVELOP...
THEY COULD BE STRONG WITH GUSTY WINDS AND LOCALLY HEAVY RAINFALL
AS THEY WOULD BE SLOW MOVERS AND PULSE IN NATURE.
PRODUCTS HAVE BEEN UPDATED.
MBS
PREV DISCUSSION... /ISSUED 622 AM CDT FRI JUN 21 2013/
DISCUSSION...
AVIATION DISCUSSION FOR THE 12Z TAFS IS BELOW.
AVIATION...
VFR CONDITIONS ARE EXPECTED TO CONTINUE.
SOUTH WINDS WILL INCREASE AND BECOME GUSTY AT ALL SITES
BY 15Z...THEN BE SLOW TO DIMINISH AFTER 01Z ACROSS
WESTERN OKLAHOMA.
MVFR CEILINGS SHOULD STAY JUST SOUTH OF KSPS-KMLC
AND DISSIPATE BY 18Z.
CHANCES FOR TSRA AND NON CONVECTIVE LOW LEVEL WIND SHEAR
APPEAR TO BE TOO LOW TO MENTION.
MBS
PREV DISCUSSION... /ISSUED 357 AM CDT FRI JUN 21 2013/
DISCUSSION...
HOT AND MAINLY RAINFREE WEATHER WILL BE THE MAIN
STORY OVER THE NEXT SEVERAL DAYS.
THIS MORNING...A FEW HIGH BASED THUNDERSTORMS WILL
CONTINUE OVER FAR NORTHWEST OKLAHOMA...MAINLY NORTHWEST
OF A CHEYENNE TO ALVA LINE. NO SEVERE STORMS ARE EXPECTED.
KEPT 10-30 PERCENT...ISOLATED TO SCATTERED COVERAGE MENTION
THIS MORNING IN THESE AREAS...THOUGH THESE STORMS MAY DISSIPATE
QUICKLY OVER THE NEXT HOUR OR TWO.
THIS AFTERNOON AND EARLY THIS EVENING...GENERALLY EXPECT ANOTHER
HOT AND DRY DAY. SOME LATEST HRRR GUIDANCE HINTED THAT ISOLATED TO
SCATTERED STORMS MAY DEVELOP NEAR A VERNON TO LAWTON TO OKLAHOMA
CITY LINE BETWEEN 1 AND 5 PM...WEAKENING TOWARDS SUNSET. THE ONLY
NOTICEABLE TRIGGER FOR LIFT WOULD BE A WEAK SHORT WAVE/POSSIBLE MCV
CURRENTLY NEAR LUBBOCK TEXAS. CHANCES OF STORMS DEVELOPING SEEM
TOO LOW TO MENTION AT THIS TIME DUE TO STRONG CAPPING...THOUGH
WILL CLOSELY MONITOR. IF STORMS DEVELOP...A FEW PULSE MICROBURSTS
WITH GUSTY WINDS AND LOCALLY HEAVY RAIN WOULD BE POSSIBLE AS THE
AIR WILL BE UNSTABLE.
LATER TONIGHT THROUGH THURSDAY...GENERALLY HOT AND RAINFREE
WEATHER WILL CONTINUE. LIKE YESTERDAY EVENING...A FEW STORMS MAY
MOVE INTO FAR WESTERN OR NORTHWESTERN OKLAHOMA EACH NIGHT...BUT
ODDS ARE GOOD THAT MOST LOCATIONS WILL STAY DRY. THINK HIGHS WILL
INCREASE SLIGHTLY EACH DAY...ESPECIALLY AS THE GROUND DRIES OUT. A
WEAK FRONT MAY MAKE IT TOWARDS THE AREA LATE WEDNESDAY INTO
THURSDAY WHICH COULD BRING A BIT HIGHER RAIN CHANCES TO THE AREA.
FOR NOW...KEPT RAIN CHANCES BELOW 20 PERCENT DURING THIS TIME
FRAME. TEMPERATURES WILL GENERALLY BE 5 TO 10 DEGREES ABOVE
AVERAGE. WEDNESDAY MAY BE THE HOTTEST DAY WITH TRIPLE DIGIT HEAT
ACROSS MUCH OF WESTERN OKLAHOMA AND WESTERN NORTH TEXAS.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 94 72 95 72 / 10 10 0 10
HOBART OK 97 71 100 71 / 20 10 0 10
WICHITA FALLS TX 98 72 99 72 / 10 10 0 0
GAGE OK 96 70 97 70 / 10 10 10 10
PONCA CITY OK 94 72 95 72 / 10 10 10 10
DURANT OK 93 72 94 72 / 10 0 10 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
23/84
AREA FORECAST DISCUSSION...UPDATED
NWS NORMAN OK
658 AM CDT FRI JUN 21 2013
.UPDATE...
REDUCED RAIN CHANCES THIS MORNING ACROSS NORTHWEST OKLAHOMA. ADDED
10 PERCENT ISOLATED MENTION ACROSS LOCATIONS SOUTHWEST OF A ENID
TO STILLWATER LINE THIS AFTERNOON.
&&
.DISCUSSION...
CONVECTION OVER NORTHWEST OKLAHOMA HAS DISSIPATED THIS
MORNING...BUT MAY REDEVELOP OVER THE NEXT FEW HOURS.
LATEST HRRR RUNS HAVE BEEN CONSISTENT IN DEVELOPING A
FEW STORMS NEAR A VERNON TO LAWTON TO OKLAHOMA CITY LINE
BETWEEN 1 AND 5 PM THIS AFTERNOON. THUS...ADDED A 10 PERCENT
ISOLATED MENTION IN THESE LOCATIONS. IF THESE STORMS DEVELOP...
THEY COULD BE STRONG WITH GUSTY WINDS AND LOCALLY HEAVY RAINFALL
AS THEY WOULD BE SLOW MOVERS AND PULSE IN NATURE.
PRODUCTS HAVE BEEN UPDATED.
MBS
&&
.PREV DISCUSSION... /ISSUED 622 AM CDT FRI JUN 21 2013/
DISCUSSION...
AVIATION DISCUSSION FOR THE 12Z TAFS IS BELOW.
AVIATION...
VFR CONDITIONS ARE EXPECTED TO CONTINUE.
SOUTH WINDS WILL INCREASE AND BECOME GUSTY AT ALL SITES
BY 15Z...THEN BE SLOW TO DIMINISH AFTER 01Z ACROSS
WESTERN OKLAHOMA.
MVFR CEILINGS SHOULD STAY JUST SOUTH OF KSPS-KMLC
AND DISSIPATE BY 18Z.
CHANCES FOR TSRA AND NON CONVECTIVE LOW LEVEL WIND SHEAR
APPEAR TO BE TOO LOW TO MENTION.
MBS
PREV DISCUSSION... /ISSUED 357 AM CDT FRI JUN 21 2013/
DISCUSSION...
HOT AND MAINLY RAINFREE WEATHER WILL BE THE MAIN
STORY OVER THE NEXT SEVERAL DAYS.
THIS MORNING...A FEW HIGH BASED THUNDERSTORMS WILL
CONTINUE OVER FAR NORTHWEST OKLAHOMA...MAINLY NORTHWEST
OF A CHEYENNE TO ALVA LINE. NO SEVERE STORMS ARE EXPECTED.
KEPT 10-30 PERCENT...ISOLATED TO SCATTERED COVERAGE MENTION
THIS MORNING IN THESE AREAS...THOUGH THESE STORMS MAY DISSIPATE
QUICKLY OVER THE NEXT HOUR OR TWO.
THIS AFTERNOON AND EARLY THIS EVENING...GENERALLY EXPECT ANOTHER
HOT AND DRY DAY. SOME LATEST HRRR GUIDANCE HINTED THAT ISOLATED TO
SCATTERED STORMS MAY DEVELOP NEAR A VERNON TO LAWTON TO OKLAHOMA
CITY LINE BETWEEN 1 AND 5 PM...WEAKENING TOWARDS SUNSET. THE ONLY
NOTICEABLE TRIGGER FOR LIFT WOULD BE A WEAK SHORT WAVE/POSSIBLE MCV
CURRENTLY NEAR LUBBOCK TEXAS. CHANCES OF STORMS DEVELOPING SEEM
TOO LOW TO MENTION AT THIS TIME DUE TO STRONG CAPPING...THOUGH
WILL CLOSELY MONITOR. IF STORMS DEVELOP...A FEW PULSE MICROBURSTS
WITH GUSTY WINDS AND LOCALLY HEAVY RAIN WOULD BE POSSIBLE AS THE
AIR WILL BE UNSTABLE.
LATER TONIGHT THROUGH THURSDAY...GENERALLY HOT AND RAINFREE
WEATHER WILL CONTINUE. LIKE YESTERDAY EVENING...A FEW STORMS MAY
MOVE INTO FAR WESTERN OR NORTHWESTERN OKLAHOMA EACH NIGHT...BUT
ODDS ARE GOOD THAT MOST LOCATIONS WILL STAY DRY. THINK HIGHS WILL
INCREASE SLIGHTLY EACH DAY...ESPECIALLY AS THE GROUND DRIES OUT. A
WEAK FRONT MAY MAKE IT TOWARDS THE AREA LATE WEDNESDAY INTO
THURSDAY WHICH COULD BRING A BIT HIGHER RAIN CHANCES TO THE AREA.
FOR NOW...KEPT RAIN CHANCES BELOW 20 PERCENT DURING THIS TIME
FRAME. TEMPERATURES WILL GENERALLY BE 5 TO 10 DEGREES ABOVE
AVERAGE. WEDNESDAY MAY BE THE HOTTEST DAY WITH TRIPLE DIGIT HEAT
ACROSS MUCH OF WESTERN OKLAHOMA AND WESTERN NORTH TEXAS.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 94 72 95 72 / 10 10 0 10
HOBART OK 97 71 100 71 / 20 10 0 10
WICHITA FALLS TX 98 72 99 72 / 10 10 0 0
GAGE OK 96 70 97 70 / 10 10 10 10
PONCA CITY OK 94 72 95 72 / 10 10 10 10
DURANT OK 93 72 94 72 / 10 0 10 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
03/17
AREA FORECAST DISCUSSION
NWS NORMAN OK
622 AM CDT FRI JUN 21 2013
.DISCUSSION...
AVIATION DISCUSSION FOR THE 12Z TAFS IS BELOW.
&&
.AVIATION...
VFR CONDITIONS ARE EXPECTED TO CONTINUE.
SOUTH WINDS WILL INCREASE AND BECOME GUSTY AT ALL SITES
BY 15Z...THEN BE SLOW TO DIMINISH AFTER 01Z ACROSS
WESTERN OKLAHOMA.
MVFR CEILINGS SHOULD STAY JUST SOUTH OF KSPS-KMLC
AND DISSIPATE BY 18Z.
CHANCES FOR TSRA AND NON CONVECTIVE LOW LEVEL WIND SHEAR
APPEAR TO BE TOO LOW TO MENTION.
MBS
&&
.PREV DISCUSSION... /ISSUED 357 AM CDT FRI JUN 21 2013/
DISCUSSION...
HOT AND MAINLY RAINFREE WEATHER WILL BE THE MAIN
STORY OVER THE NEXT SEVERAL DAYS.
THIS MORNING...A FEW HIGH BASED THUNDERSTORMS WILL
CONTINUE OVER FAR NORTHWEST OKLAHOMA...MAINLY NORTHWEST
OF A CHEYENNE TO ALVA LINE. NO SEVERE STORMS ARE EXPECTED.
KEPT 10-30 PERCENT...ISOLATED TO SCATTERED COVERAGE MENTION
THIS MORNING IN THESE AREAS...THOUGH THESE STORMS MAY DISSIPATE
QUICKLY OVER THE NEXT HOUR OR TWO.
THIS AFTERNOON AND EARLY THIS EVENING...GENERALLY EXPECT ANOTHER
HOT AND DRY DAY. SOME LATEST HRRR GUIDANCE HINTED THAT ISOLATED TO
SCATTERED STORMS MAY DEVELOP NEAR A VERNON TO LAWTON TO OKLAHOMA
CITY LINE BETWEEN 1 AND 5 PM...WEAKENING TOWARDS SUNSET. THE ONLY
NOTICEABLE TRIGGER FOR LIFT WOULD BE A WEAK SHORT WAVE/POSSIBLE MCV
CURRENTLY NEAR LUBBOCK TEXAS. CHANCES OF STORMS DEVELOPING SEEM
TOO LOW TO MENTION AT THIS TIME DUE TO STRONG CAPPING...THOUGH
WILL CLOSELY MONITOR. IF STORMS DEVELOP...A FEW PULSE MICROBURSTS
WITH GUSTY WINDS AND LOCALLY HEAVY RAIN WOULD BE POSSIBLE AS THE
AIR WILL BE UNSTABLE.
LATER TONIGHT THROUGH THURSDAY...GENERALLY HOT AND RAINFREE
WEATHER WILL CONTINUE. LIKE YESTERDAY EVENING...A FEW STORMS MAY
MOVE INTO FAR WESTERN OR NORTHWESTERN OKLAHOMA EACH NIGHT...BUT
ODDS ARE GOOD THAT MOST LOCATIONS WILL STAY DRY. THINK HIGHS WILL
INCREASE SLIGHTLY EACH DAY...ESPECIALLY AS THE GROUND DRIES OUT. A
WEAK FRONT MAY MAKE IT TOWARDS THE AREA LATE WEDNESDAY INTO
THURSDAY WHICH COULD BRING A BIT HIGHER RAIN CHANCES TO THE AREA.
FOR NOW...KEPT RAIN CHANCES BELOW 20 PERCENT DURING THIS TIME
FRAME. TEMPERATURES WILL GENERALLY BE 5 TO 10 DEGREES ABOVE
AVERAGE. WEDNESDAY MAY BE THE HOTTEST DAY WITH TRIPLE DIGIT HEAT
ACROSS MUCH OF WESTERN OKLAHOMA AND WESTERN NORTH TEXAS.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 94 72 95 72 / 10 10 0 10
HOBART OK 97 71 100 71 / 10 10 0 10
WICHITA FALLS TX 98 72 99 72 / 10 10 0 0
GAGE OK 96 70 97 70 / 10 10 10 10
PONCA CITY OK 94 72 95 72 / 0 10 10 10
DURANT OK 93 72 94 72 / 0 0 10 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
03/17/17
AREA FORECAST DISCUSSION
NWS NORMAN OK
357 AM CDT FRI JUN 21 2013
.DISCUSSION...
HOT AND MAINLY RAINFREE WEATHER WILL BE THE MAIN
STORY OVER THE NEXT SEVERAL DAYS.
THIS MORNING...A FEW HIGH BASED THUNDERSTORMS WILL
CONTINUE OVER FAR NORTHWEST OKLAHOMA...MAINLY NORTHWEST
OF A CHEYENNE TO ALVA LINE. NO SEVERE STORMS ARE EXPECTED.
KEPT 10-30 PERCENT...ISOLATED TO SCATTERED COVERAGE MENTION
THIS MORNING IN THESE AREAS...THOUGH THESE STORMS MAY DISSIPATE
QUICKLY OVER THE NEXT HOUR OR TWO.
THIS AFTERNOON AND EARLY THIS EVENING...GENERALLY EXPECT ANOTHER
HOT AND DRY DAY. SOME LATEST HRRR GUIDANCE HINTED THAT ISOLATED TO
SCATTERED STORMS MAY DEVELOP NEAR A VERNON TO LAWTON TO OKLAHOMA
CITY LINE BETWEEN 1 AND 5 PM...WEAKENING TOWARDS SUNSET. THE ONLY
NOTICEABLE TRIGGER FOR LIFT WOULD BE A WEAK SHORT WAVE/POSSIBLE MCV
CURRENTLY NEAR LUBBOCK TEXAS. CHANCES OF STORMS DEVELOPING SEEM
TOO LOW TO MENTION AT THIS TIME DUE TO STRONG CAPPING...THOUGH
WILL CLOSELY MONITOR. IF STORMS DEVELOP...A FEW PULSE MICROBURSTS
WITH GUSTY WINDS AND LOCALLY HEAVY RAIN WOULD BE POSSIBLE AS THE
AIR WILL BE UNSTABLE.
LATER TONIGHT THROUGH THURSDAY...GENERALLY HOT AND RAINFREE
WEATHER WILL CONTINUE. LIKE YESTERDAY EVENING...A FEW STORMS MAY
MOVE INTO FAR WESTERN OR NORTHWESTERN OKLAHOMA EACH NIGHT...BUT
ODDS ARE GOOD THAT MOST LOCATIONS WILL STAY DRY. THINK HIGHS WILL
INCREASE SLIGHTLY EACH DAY...ESPECIALLY AS THE GROUND DRIES OUT. A
WEAK FRONT MAY MAKE IT TOWARDS THE AREA LATE WEDNESDAY INTO
THURSDAY WHICH COULD BRING A BIT HIGHER RAIN CHANCES TO THE AREA.
FOR NOW...KEPT RAIN CHANCES BELOW 20 PERCENT DURING THIS TIME
FRAME. TEMPERATURES WILL GENERALLY BE 5 TO 10 DEGREES ABOVE
AVERAGE. WEDNESDAY MAY BE THE HOTTEST DAY WITH TRIPLE DIGIT HEAT
ACROSS MUCH OF WESTERN OKLAHOMA AND WESTERN NORTH TEXAS.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 94 72 95 72 / 10 10 0 10
HOBART OK 97 71 100 71 / 10 10 0 10
WICHITA FALLS TX 98 72 99 72 / 10 10 0 0
GAGE OK 96 70 97 70 / 10 10 10 10
PONCA CITY OK 94 72 95 72 / 0 10 10 10
DURANT OK 93 72 94 72 / 0 0 10 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
03/17
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
1156 PM CDT THU JUN 20 2013
.UPDATE...FOR 06Z AVIATION DISCUSSION.
&&
.AVIATION...06Z AVIATION DISCUSSION.
UNCERTANTIES...SHWRS/TSTMS ACTUAL LOCATION DEVELOPMENTAL IMPACTS...
MVFR FOG FORMATION THRU 21/15Z. WITH RAINFALL NEAR ALL TAF SITES FROM
AFTERNOON/EVENING CONVECTION...EXPECT WITH LIGHT WINDS AND RADITIONAL
POTENTIAL THE POSSIBILITY OF TEMPO MVFR FOG CONDITIONS 21/08Z-21/12Z...
MOST ENHANCED CSV. EXPECT ISO/SCT DIURNAL BASED SHWRS/TSTMS 21/19Z-22/02Z...
BUT WITH LOCATIONAL DEVELOPMENT HARD TO PINPOINT THIS FAR OUT...BUT
THE POSSIBILITY STILL THERE...WILL GO WITH VCTS REMARKS WITH CB MENTIONED.
ACTIVITY SHOULD DISSIPATE BY 22/02Z WITH SCT CI POSSIBLE THRU 22/06Z.
&&
.PREV DISCUSSION.../ISSUED 753 PM CDT THU JUN 20 2013/
UPDATE...
WEAK MID LEVEL IMPULSE IN PLACE ACROSS THE MID STATE THIS EVENING.
THIS HAS HELPED TO PRODUCE THE ISOL TO SCT SHOWER AND TSTM
ACTIVITY EARLIER THIS AFTERNOON AND EVENING. ACTIVITY IS BEGINNING
TO TAPER OFF AS WE CONTINUE TO LOSE OUR DAYTIME HEATING. LATEST
00Z LAPS INSTABILITY DATA SHOWING A MARKED DECREASE IN INSTABILITY
LEVELS FROM 23Z TO 00Z. RADAR IS ALSO SHOWING A DECREASE IN
INTENSITY AND IS FURTHER SUPPORTED BY AN HRRR CONVECTIVE DECREASE
WITH TIME.
WILL ISSUE UPDATE TO REMOVE THE LATE AFTERNOON WORDING.
OTW...CONVECTION WILL STILL CONTINUE FOR ANOTHER HOUR OR TWO. ONCE
CONVECTION COMPLETELY WINDS DOWN WILL REISSUE AGAIN AND REMOVE ALL
CONVECTION FROM ZONES. REMAINDER OF THE GRIDDED DATA LOOKS TO BE
IN GOOD SHAPE. UPDATE WILL BE ISSUED SHORTLY.
PREV DISCUSSION.../ISSUED 623 PM CDT THU JUN 20 2013/
AVIATION 00Z DISCUSSION...
WEAK MID LEVEL IMPULSE WILL MOVE EASTWARD ACROSS THE MID STATE
THROUGH EARLY EVENING. AS A RESULT...ISOL SHOWERS AND TSTMS WILL
BE POSSIBLE...GENERALLY PRIOR TO 03Z AND MAINLY ACROSS EASTERN
AREAS OF THE MID STATE. AFT 03Z...SKIES WILL CLEAR WITH SOME
SLIGHT BR VSBY REDUCTION FROM 06Z-12Z. SCT CONVECTIVE CU DECK AT 5KFT
WILL RETURN ON FRIDAY AFTERNOON WITH ISOL STORMS POSSIBLE...MAINLY
CSV AREA.
PREV DISCUSSION.../ISSUED 304 PM CDT THU JUN 20 2013/
DISCUSSION...
WEAK UPPER TROUGH REMAINS OVER THE REGION THIS AFTERNOON WITH
SHORTWAVE JUST UPSTREAM. MODERATE MOISTURE SOURCE AND SLIGHTLY
INCREASED INSTABILITY EXPECTED TO CONTINUE ISO-SCT CONVECTION
INTO THE EARLY EVE.
WEAK UPPER TROUGH WILL MAKE SLOW TRANSITION TO RIDGING INTO THE
LATE WEEKEND...ALTHOUGH WEAK TROUGH AXIS DOES LINGER ALONG THE
EASTERN SEABOARD. THIS WILL KEEP ANYTHING ORGANIZED FROM AFFECTING
THE MID-SOUTH THUS CURRENT TREND WILL CONTINUE. MODERATE MOISTURE
BELOW H7 AND DAYTIME HEATING/ELEVATED INSTABILITY WILL KEEP
LARGELY DIURNAL ISO-SCT STORMS IN THE MIX THROUGH LATE SUNDAY.
NO REAL APPRECIABLE CHANGES IN OVERALL PATTERN EARLY NEXT WEEK
BUT CHANGES ARE IN SIGHT BY EARLY WED. UPPER RIDGE BREAKING DOWN
MID-WEEK AS UPPER LOW SCOOTS NEAR THE US/CANADIAN BORDER. THIS
WILL SHARPEN TROUGH OVER THE EASTERN US LATE WEEK...WITH AXIS
SWINGING THROUGH POSSIBLY FRI. DAYTIME HEATING PUSHING TEMPS WELL
INTO THE 80S TO AROUND 90 WILL PRODUCE DIURNAL CONVECTION THROUGH
WED...WITH PCPN CHANCES RAMPING UP LATE IN THE WEEK WITH INCOMING
TROUGH.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
31
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
915 PM CDT SAT JUN 22 2013
.UPDATE...
RETAINED ISOLATED THUNDER THIS EVENING ONLY IN THE SOUTHWESTERN
SOUTH PLAINS WHERE SHOWERS HAVE AT LEAST BEEN FLIRTING WITH THE
AREA. OTHERWISE...LATEST SHORT-TERM GUIDANCE HAS CONFIRMED MOST
TRENDS THAT THUNDER CHANCES CONTINUE TO DWINDLE. UPDATED FOR LOWER
THUNDERSTORM CHANCES AND REMOVAL OF SEVERE WORDING FOR THIS
EVENING. RMCQUEEN
&&
.PREV DISCUSSION... /ISSUED 723 PM CDT SAT JUN 22 2013/
UPDATE...
THUNDERSTORM OPPORTUNITIES APPEAR DIMINISHING WITH DECREASING
CUMULUS FIELD TO OUR SOUTHWEST...OVERSPREADING HIGH CLOUDS WITH
SLOWLY FALLING TEMPERATURES...AND STILL 40 TO 60 JOULES PER
KILOGRAM OF CONVECTIVE INHIBITION TO OVERCOME. LATEST RAP SPREADS
EVEN HIGHER INHIBITION AIRMASS INTO THE AREA BY 02Z-03Z WITH
LATEST RUN INDICATING ONLY VERY ISOLATED STORMS IN THE NEXT HOUR OR
TWO....WHILE THE HRRR HAS BEEN FAR OVERDONE AND TOO FAST WITH
DEVELOPMENT TO OUR NORTH...BUT AT LEAST HAS BEEN PLAYING DOWN
THUNDER DEVELOPMENT OVER MUCH OF THE SOUTH PLAINS AREA. CONVECTIVE
ENERGY SHOULD IT BE RELEASED AND COMBINED WITH 30-35 KNOTS OF DEEP
LAYER SHEAR WOULD INDICATE A POTENTIAL FOR SEVERE STORMS YET...SO
WE WILL MAINTAIN CURRENT FORECAST OF LOW THUNDER CHANCES FOR NOW.
RMCQUEEN
AVIATION...
VFR WITH MODERATE SURFACE TROUGH AND UPPER LEVEL SOUTHWEST FLOW
WILL DOMINATE. THUNDER CHANCES APPEAR ONLY MARGINAL AT THIS POINT
MAINLY FOR KLBB THIS EVENING...SO WE WILL NOT INCLUDE MORE THAN A
VICINITY MENTION IN THE KLBB TAF FOR NOW. RMCQUEEN
PREV DISCUSSION... /ISSUED 325 PM CDT SAT JUN 22 2013/
SHORT TERM...
THE PRIMARY FOCUS REMAINS ON CONVECTIVE CHANCES LATE THIS AFTERNOON
INTO THE EVENING AND AGAIN ON STORM CHANCES LATE TOMORROW
AFTERNOON...INCLUDING THE PROSPECTS FOR SEVERE WEATHER. LARGE SCALE
PATTERN WILL NOT CHANGE MUCH LOCALLY AS THE REGION REMAINS ON THE
SOUTHERN FRINGE OF SOUTHWESTERLY FLOW ALOFT. ONE PRONOUNCED
SHORTWAVE TROUGH WILL LIFT ACROSS THE NORTHERN HIGH PLAINS TONIGHT
WHILE WATER VAPOR IMAGERY DOES SHOW INCREASING SUPPORT/MOISTENING
APPROACHING THROUGH NM AND AZ. WEAK SUPPORT ALOFT COUPLED WITH A
DRYLINE CURRENTLY TIGHTENING ACROSS THE FAR WESTERN ZONES SHOULD BE
ENOUGH TO TRIGGER SCATTERED CONVECTION BY LATE THIS AFTERNOON OR
EARLY THIS EVENING. STRONG INSTABILITY ALONG AND ESPECIALLY JUST
EAST OF THE DRYLINE AND IMPROVING 0-6 KM SHEAR WILL SUPPORT A SEVERE
WEATHER RISK INTO THIS EVENING...INCLUDING DAMAGING WINDS AND LARGE
HAIL. IN ADDITION...STORM MOTIONS WILL BE FAIRLY SLOW...PARTICULARLY
IF ANY MID-LEVEL CYCLONIC ROTATION CAN BE ACQUIRED /WHICH WILL BE
POSSIBLE/ AND GIVEN ABOVE AVERAGE PWATS IN PLACE...A LOCALIZED HEAVY
RAIN THREAT WILL EXIST. IN GENERAL...THIS ACTIVITY WILL ADVANCE
EASTWARD BUT WILL LIKELY HAVE DIFFICULTY MOVING TOO FAR OFF INTO THE
ROLLING PLAINS GIVEN THE STRONGER INHIBITION PROGGED THERE.
CONVECTION WILL WANE LATE TONIGHT BUT A SIMILAR SETUP WILL REDEVELOP
ON SUNDAY SETTING THE STAGE FOR ANOTHER CHANCE OF STORMS...PRIMARILY
ON THE CAPROCK. LATEST GUIDANCE DOES SUGGEST MOISTURE...INSTABILITY
AND SHEAR WILL BE LOWER THAN TODAY SO THIS MAY MODULATE STORM
COVERAGE AND INTENSITY SUNDAY AFTERNOON. OTHERWISE...MILD CONDITIONS
WILL CONTINUE WITH LOWS TONIGHT RANGING FROM THE MID 60S NORTHWEST
TO MID 70S SOUTHEAST AND AFTERNOON HIGHS ON SUNDAY WELL INTO THE
90S.
LONG TERM...
NO SIGNIFICANT CHANGES TO THE FCST THIS AFTN. STILL APPEARS THAT
MONDAY WILL BE THE LAST DAY TO SEE THUNDERSTORMS IN THE LOW LEVEL
MOISTURE AXIS UNDERNEATH SWLY MID TO UPPER LEVEL FLOW BEFORE UPPER
RIDGING BUILDS OVER THE ROCKIES. THAT RIDGE SHOULD SHUT
EFFECTIVELY SHUT OFF PRECIP CHANCES FOR TUESDAY THROUGH THURSDAY
AND INCREASED HEIGHTS AND THICKNESSES CONTINUE TO SUGGEST WARMER
TEMPERATURES...BUT STAYING AWAY FROM EXTREME HEAT WITH THE HEIGHT
AND THERMAL RIDGES CENTERED OVER COLORADO AND NORTHERN NEW MEXICO.
STILL A SIGNAL IN THE MEDIUM RANGE OF PRECIP WORKING INTO THE FCST
AREA FRIDAY AND/OR SATURDAY AS THE UPPER RIDGE SHIFTS WWD TOWARD
UTAH AND ARIZONA ALLOWING DEEPER NORTHERLY FLOW TO DEVELOP ACROSS
THE PLAINS AND THUS THE POSSIBILITY OF A COLD FRONT AND UPPER
DISTURBANCES TO ADVANCE TOWARD THE AREA. WILL NUDGE POPS TOWARD
SLIGHT CHANCE BUT KEEP THEM JUST BELOW MENTION WAITING TO SEE IF
FUTURE RUNS CONTINUE TO ADVERTISE THIS PATTERN.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 64 94 66 93 66 / 10 20 20 20 20
TULIA 66 93 67 94 67 / 10 20 20 20 20
PLAINVIEW 68 92 67 93 69 / 10 20 20 20 20
LEVELLAND 65 94 68 92 69 / 10 20 20 20 20
LUBBOCK 70 94 69 94 71 / 10 20 20 20 20
DENVER CITY 66 97 69 94 69 / 20 20 20 20 20
BROWNFIELD 65 95 68 92 69 / 20 20 20 20 20
CHILDRESS 72 96 70 96 71 / 10 10 10 10 10
SPUR 70 93 70 94 71 / 10 10 10 10 10
ASPERMONT 75 96 71 97 73 / 10 10 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
05/99
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
723 PM CDT SAT JUN 22 2013
.UPDATE...
THUNDERSTORM OPPORTUNITIES APPEAR DIMINISHING WITH DECREASING
CUMULUS FIELD TO OUR SOUTHWEST...OVERSPREADING HIGH CLOUDS WITH
SLOWLY FALLING TEMPERATURES...AND STILL 40 TO 60 JOULES PER
KILOGRAM OF CONVECTIVE INHIBITION TO OVERCOME. LATEST RAP SPREADS
EVEN HIGHER INHIBITION AIRMASS INTO THE AREA BY 02Z-03Z WITH
LATEST RUN INDICATING ONLY VERY ISOLATED STORMS IN THE NEXT HOUR OR
TWO....WHILE THE HRRR HAS BEEN FAR OVERDONE AND TOO FAST WITH
DEVELOPMENT TO OUR NORTH...BUT AT LEAST HAS BEEN PLAYING DOWN
THUNDER DEVELOPMENT OVER MUCH OF THE SOUTH PLAINS AREA. CONVECTIVE
ENERGY SHOULD IT BE RELEASED AND COMBINED WITH 30-35 KNOTS OF DEEP
LAYER SHEAR WOULD INDICATE A POTENTIAL FOR SEVERE STORMS YET...SO
WE WILL MAINTAIN CURRENT FORECAST OF LOW THUNDER CHANCES FOR NOW.
RMCQUEEN
&&
.AVIATION...
VFR WITH MODERATE SURFACE TROUGH AND UPPER LEVEL SOUTHWEST FLOW
WILL DOMINATE. THUNDER CHANCES APPEAR ONLY MARGINAL AT THIS POINT
MAINLY FOR KLBB THIS EVENING...SO WE WILL NOT INCLUDE MORE THAN A
VICINITY MENTION IN THE KLBB TAF FOR NOW. RMCQUEEN
&&
.PREV DISCUSSION... /ISSUED 325 PM CDT SAT JUN 22 2013/
SHORT TERM...
THE PRIMARY FOCUS REMAINS ON CONVECTIVE CHANCES LATE THIS AFTERNOON
INTO THE EVENING AND AGAIN ON STORM CHANCES LATE TOMORROW
AFTERNOON...INCLUDING THE PROSPECTS FOR SEVERE WEATHER. LARGE SCALE
PATTERN WILL NOT CHANGE MUCH LOCALLY AS THE REGION REMAINS ON THE
SOUTHERN FRINGE OF SOUTHWESTERLY FLOW ALOFT. ONE PRONOUNCED
SHORTWAVE TROUGH WILL LIFT ACROSS THE NORTHERN HIGH PLAINS TONIGHT
WHILE WATER VAPOR IMAGERY DOES SHOW INCREASING SUPPORT/MOISTENING
APPROACHING THROUGH NM AND AZ. WEAK SUPPORT ALOFT COUPLED WITH A
DRYLINE CURRENTLY TIGHTENING ACROSS THE FAR WESTERN ZONES SHOULD BE
ENOUGH TO TRIGGER SCATTERED CONVECTION BY LATE THIS AFTERNOON OR
EARLY THIS EVENING. STRONG INSTABILITY ALONG AND ESPECIALLY JUST
EAST OF THE DRYLINE AND IMPROVING 0-6 KM SHEAR WILL SUPPORT A SEVERE
WEATHER RISK INTO THIS EVENING...INCLUDING DAMAGING WINDS AND LARGE
HAIL. IN ADDITION...STORM MOTIONS WILL BE FAIRLY SLOW...PARTICULARLY
IF ANY MID-LEVEL CYCLONIC ROTATION CAN BE ACQUIRED /WHICH WILL BE
POSSIBLE/ AND GIVEN ABOVE AVERAGE PWATS IN PLACE...A LOCALIZED HEAVY
RAIN THREAT WILL EXIST. IN GENERAL...THIS ACTIVITY WILL ADVANCE
EASTWARD BUT WILL LIKELY HAVE DIFFICULTY MOVING TOO FAR OFF INTO THE
ROLLING PLAINS GIVEN THE STRONGER INHIBITION PROGGED THERE.
CONVECTION WILL WANE LATE TONIGHT BUT A SIMILAR SETUP WILL REDEVELOP
ON SUNDAY SETTING THE STAGE FOR ANOTHER CHANCE OF STORMS...PRIMARILY
ON THE CAPROCK. LATEST GUIDANCE DOES SUGGEST MOISTURE...INSTABILITY
AND SHEAR WILL BE LOWER THAN TODAY SO THIS MAY MODULATE STORM
COVERAGE AND INTENSITY SUNDAY AFTERNOON. OTHERWISE...MILD CONDITIONS
WILL CONTINUE WITH LOWS TONIGHT RANGING FROM THE MID 60S NORTHWEST
TO MID 70S SOUTHEAST AND AFTERNOON HIGHS ON SUNDAY WELL INTO THE
90S.
LONG TERM...
NO SIGNIFICANT CHANGES TO THE FCST THIS AFTN. STILL APPEARS THAT
MONDAY WILL BE THE LAST DAY TO SEE THUNDERSTORMS IN THE LOW LEVEL
MOISTURE AXIS UNDERNEATH SWLY MID TO UPPER LEVEL FLOW BEFORE UPPER
RIDGING BUILDS OVER THE ROCKIES. THAT RIDGE SHOULD SHUT
EFFECTIVELY SHUT OFF PRECIP CHANCES FOR TUESDAY THROUGH THURSDAY
AND INCREASED HEIGHTS AND THICKNESSES CONTINUE TO SUGGEST WARMER
TEMPERATURES...BUT STAYING AWAY FROM EXTREME HEAT WITH THE HEIGHT
AND THERMAL RIDGES CENTERED OVER COLORADO AND NORTHERN NEW MEXICO.
STILL A SIGNAL IN THE MEDIUM RANGE OF PRECIP WORKING INTO THE FCST
AREA FRIDAY AND/OR SATURDAY AS THE UPPER RIDGE SHIFTS WWD TOWARD
UTAH AND ARIZONA ALLOWING DEEPER NORTHERLY FLOW TO DEVELOP ACROSS
THE PLAINS AND THUS THE POSSIBILITY OF A COLD FRONT AND UPPER
DISTURBANCES TO ADVANCE TOWARD THE AREA. WILL NUDGE POPS TOWARD
SLIGHT CHANCE BUT KEEP THEM JUST BELOW MENTION WAITING TO SEE IF
FUTURE RUNS CONTINUE TO ADVERTISE THIS PATTERN.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 64 94 66 93 66 / 20 20 20 20 20
TULIA 66 93 67 94 67 / 30 20 20 20 20
PLAINVIEW 68 92 67 93 69 / 30 20 20 20 20
LEVELLAND 65 94 68 92 69 / 30 20 20 20 20
LUBBOCK 70 94 69 94 71 / 30 20 20 20 20
DENVER CITY 66 97 69 94 69 / 30 20 20 20 20
BROWNFIELD 65 95 68 92 69 / 30 20 20 20 20
CHILDRESS 72 96 70 96 71 / 10 10 10 10 10
SPUR 70 93 70 94 71 / 10 10 10 10 10
ASPERMONT 75 96 71 97 73 / 10 10 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
05/99/05
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
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.
&&
$$
23/07
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1246 PM CDT FRI JUN 21 2013
.AVIATION...
BREEZY SOUTHERLY WINDS WERE BEGINNING TO LOFT SOME BLDU AT LBB
AGAIN THOUGH NOT QUITE TO THE DEGREE OF YESTERDAY AT THIS SAME
TIME. STILL...THINK VISIBILITIES WILL DROP TO MVFR LEVELS THIS
AFTERNOON BEFORE IMPROVING THIS EVENING WHEN WINDS SUBSIDE AND/OR
SHOWERS CLEAR OUT THE AIR. OTHER CONCERN REVOLVES AROUND
CONVECTIVE CHANCES AT THE TERMINALS THIS AFTERNOON INTO THE
EVENING. CDS OR LBB COULD SEE A STORM FROM MID-LATE AFTN THROUGH
THE EVENING. THINK BEST CHANCES WILL BE AT LBB THIS EVENING THOUGH
CONFIDENCE NOT TERRIBLY HIGH OF A DIRECT IMPACT. THUS HAVE
INCLUDED A VCTS MENTION AT LBB FROM 23-03Z...THOUGH WILL OBVIOUSLY
MONITOR CLOSELY AND AMEND AS NECESSARY.
&&
.PREV DISCUSSION... /ISSUED 1059 AM CDT FRI JUN 21 2013/
UPDATE...
MINOR UPDATE TO EXPAND POPS TO INCLUDE THE EASTERN ZONES THIS
AFTERNOON. ALSO CHANGED BLOWING DUST MENTION FROM PATCHY TO AREAS
ON MUCH OF THE CAPROCK INTO THE WESTERN ROLLING PLAINS FOR THIS
AFTERNOON INTO THE EVENING HOURS.
MORNING WATER VAPOR IMAGERY SHOWS SOUTHWESTERLY FLOW ALOFT OVER
THE REGION...WITH A RIBBON OF MID-LEVEL MOISTURE STRETCHING FROM
KANSAS SOUTHWARD THROUGH OKLAHOMA...THE EASTERN PANHANDLES AND
THROUGH THE EASTERN 1/2 OF THE CWA THEN TO POINTS SOUTH AND
SOUTHWEST. THIS SUB-TROPICAL MOISTURE FETCH WAS IN ADVANCE OF A
EAST-NORTHEASTWARD MOVING SHORTWAVE TROUGH THAT HAS ALREADY AIDED
IN A FEW SHOWERS/STORMS ACROSS THE CENTRAL PANHANDLE THIS MORNING.
RECENT HRRR AND RAP GUIDANCE INDICATE SAID FACTORS WILL BE ENOUGH
TO DEVELOP ISOLATED TO SCATTERED MOIST CONVECTION OFF THE CAPROCK
THIS AFTERNOON AND FOR THIS REASON HAVE INSERTED A SLIGHT CHANCE
OF STORMS THERE AFTER 18Z. FURTHER WEST...DRIER MID-LEVEL AIR IS
WORKING INTO THE REGION...BUT THE SFC TROUGH AND STRONG HEATING
SHOULD BE ENOUGH TO POP ADDITIONAL ISOLATED TO SCATTERED
THUNDERSTORMS THIS AFTERNOON SOMEWHERE NEAR OR JUST WEST OF THE
TX/NM LINE...WHICH WILL MOVE EASTWARD THROUGH THE EVENING HOURS
WHILE GRADUALLY WANING IN INTENSITY. FAIRLY STRONG INSTABILITY
/SBCAPES PUSHING 2000 J/KG/ AND MODEST DEEP LAYER SHEAR /GENERALLY
AOB 35 KNOTS/ COULD SUPPORT A FEW STRONG/SEVERE CELLS...THOUGH
OVERALL STORM ORGANIZATION WILL LIKELY BE LIMITED. IN ADDITION TO
THE POSSIBILITY OF DUSTY OUTFLOWS WITH ANY CONVECTION...BREEZY
SOUTHERLY WINDS WILL LIKELY RESULT IN A FAIR AMOUNT OF BLOWING
DUST AGAIN THIS AFTERNOON INTO THE EVENING...SIMILAR TO YESTERDAY.
THE REMAINDER OF THE FORECAST REMAINS IN GOOD SHAPE. UPDATE
PRODUCTS HAVE BEEN SENT.
PREV DISCUSSION... /ISSUED 638 AM CDT FRI JUN 21 2013/
AVIATION...
BREEZY SOUTH WINDS WILL GUST TO NEAR 30 KNOTS TODAY AS A SURFACE
TROUGH REMAINS IN CLOSE PROXIMITY TO BOTH TERMINALS. THEREFORE...WILL
LEAVE PREVAILING MVFR CONDITIONS IN FOR BOTH SITES FROM MID-LATE
MORNING THROUGH MID EVENING GIVEN THE LIKELIHOOD OF BLOWING DUST
AGAIN TODAY. KLBB WILL SEE A BETTER CHANCE FOR SHOWERS OR STORMS
IN THE VICINITY THAN KCDS...BUT CONFIDENCE IN COVERAGE IS NOT HIGH
ENOUGH AT THIS TIME TO WARRANT MENTION.
PREV DISCUSSION... /ISSUED 409 AM CDT FRI JUN 21 2013/
SHORT TERM...
ISOLATED SHOWERS AND EMBEDDED THUNDER WILL CONTINUE TO WANE INTO THE
EARLY MORNING HOURS. TIGHTENING SURFACE TROUGH NEAR THE NEW MEXICO
STATE LINE ALONG WITH POSITIONING BEHIND A WAKE LOW NEAR THE
INTERSTATE 40 CORRIDOR EAST OF AMARILLO HAVE KEPT WIND GUSTS IN THE
40 TO 50 MPH RANGE ON AN ABERNATHY TO FLOYDADA LINE. SHOULD SEE
THESE STRONG GUSTS EXIT TO THE NORTH AND EAST AS THE WAKE LOW MOVES
OFF IN THIS DIRECTION AND PRESSURE GRADIENT SOMEWHAT WEAKENS AWAY
FROM THE TROUGH AXIS.
SOUTHWEST FLOW REGIME WILL MAINTAIN ITSELF ALOFT TODAY AS BROAD
TROUGHING BLANKETS MUCH OF THE WESTERN CONUS WITH UPPER RIDGING
SOUTHEAST OF WEST TEXAS. FALLING PRESSURES IN CORRESPONDENCE WITH
THE ABOVE REFERENCED DEEPENING SURFACE TROUGH EXTENDING FROM THE
FRONT RANGE INTO EASTERN NEW MEXICO WILL LEAD TO THE BEST
THUNDERSTORM CHANCES ACROSS THE FAR SOUTHWEST PANHANDLE AND WESTERN
SOUTH PLAINS. RIBBON OF THETA-E VALUES WILL BE HIGHEST HERE WITH
GREATER INSTABILITY AS SUFFICIENT MOISTURE REMAINS IN PLACE WITH
DEWPOINTS IN THE UPPER 50S TO LOWER 60S.
MORE PRONOUNCED ELEVATED MIXED LAYER TO THE EAST INTO THE
ROLLING PLAINS AND EXTREME SOUTHEAST PANHANDLE WILL PRECLUDE
CONVECTIVE INITIATION...BUT A 30 TO 40 KNOT LOW LEVEL JET AND
INCREASING DEEP LAYER SHEAR TO NEAR 30 KNOTS MAY BE ENOUGH FOR
PREEXISTING ACTIVITY TO SKIRT EAST OFF THE CAPROCK. STEEP LAPSE RATES
ON EITHER SIDE OF THE ELEVATED MIXED LAYER AND RELATIVELY DRY NEAR
SURFACE AIR DUE TO TEMPERATURES IN THE 90S WILL PROMOTE LARGE HAIL
AND WIND GUSTS OF 50 TO 60 MPH IN STRONGER STORMS WEST OF THE
ESCARPMENT DURING THE AFTERNOON AND EARLY EVENING. STORMS SHOULD
WIND DOWN POST DIURNAL HEATING AND LEAVE A FEW STRAGGLING SHOWERS
MOVING TO THE NORTH AND EAST. WINDS WILL REMAIN IN THE 10 TO 15 MPH
RANGE OVERNIGHT AND COMBINE WITH RESIDUAL MOISTURE TO KEEP LOW
TEMPERATURES A FEW DEGREES ABOVE CLIMATOLOGY...RANGING FROM THE MID
TO UPPER 60S ON THE CAPROCK AND UPPER 60S TO LOW 70S IN THE ROLLING
PLAINS AND FAR SOUTHEAST PANHANDLE.
LONG TERM...
BY SATURDAY MORNING...ELONGATED UPPER LOW WILL BE POSITIONED FROM
IDAHO TO NORTHERN AB/SK WITH BROAD SOUTHWESTERLY FLOW ACROSS THE
CENTRAL STATES. HIGH WILL CONTINUE TO STRENGTHEN ACROSS THE
SOUTHEASTERN USA THOUGH THERE WILL BE A WEAKNESS OUT NEAR THE
SMOKY MTNS. THE HIGH WILL BUILD AND SHIFT EAST TO WEST BY THE
MIDDLE OF NEXT WEEK BEFORE STRENGTHENING FURTHER OVER THE FOUR
CORNERS BY LATE IN THE WEEK WITH THE PATTERN LARGELY REMAINING
STAGNANT OUT THROUGH 240 HOURS.
INDICATIONS SUGGEST THAT THE WET PATTERN ACROSS OUR WESTERN ZONES
WILL CONTINUE THROUGH AT LEAST SUNDAY WITH LESS OPPORTUNITY MONDAY
EVENING AND THEREAFTER AS PATTERN CHANGES OVERHEAD. HAVE BUMPED
POPS SAT/SUN AND TRIMMED MONDAY LEAVING THINGS DRY THEREAFTER.
TEMPERATURES WILL BE ON THE INCREASE NEXT WEEK WITH VALUES
APPROACHING THE CENTURY MARK BY MID WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 64 94 63 95 63 / 30 20 20 20 20
TULIA 66 93 66 94 66 / 30 20 20 20 20
PLAINVIEW 68 93 67 93 67 / 30 20 20 20 20
LEVELLAND 68 94 68 94 67 / 30 20 20 20 20
LUBBOCK 69 94 69 94 68 / 20 10 20 20 20
DENVER CITY 67 94 69 95 68 / 30 20 20 20 20
BROWNFIELD 68 94 69 94 69 / 20 20 20 20 20
CHILDRESS 70 97 70 96 71 / 20 10 10 10 10
SPUR 70 97 71 97 70 / 20 10 10 10 10
ASPERMONT 71 99 72 98 72 / 20 10 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
23
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
1059 AM CDT FRI JUN 21 2013
.UPDATE...
MINOR UPDATE TO EXPAND POPS TO INCLUDE THE EASTERN ZONES THIS
AFTERNOON. ALSO CHANGED BLOWING DUST MENTION FROM PATCHY TO AREAS
ON MUCH OF THE CAPROCK INTO THE WESTERN ROLLING PLAINS FOR THIS
AFTERNOON INTO THE EVENING HOURS.
MORNING WATER VAPOR IMAGERY SHOWS SOUTHWESTERLY FLOW ALOFT OVER
THE REGION...WITH A RIBBON OF MID-LEVEL MOISTURE STRETCHING FROM
KANSAS SOUTHWARD THROUGH OKLAHOMA...THE EASTERN PANHANDLES AND
THROUGH THE EASTERN 1/2 OF THE CWA THEN TO POINTS SOUTH AND
SOUTHWEST. THIS SUB-TROPICAL MOISTURE FETCH WAS IN ADVANCE OF A
EAST-NORTHEASTWARD MOVING SHORTWAVE TROUGH THAT HAS ALREADY AIDED
IN A FEW SHOWERS/STORMS ACROSS THE CENTRAL PANHANDLE THIS MORNING.
RECENT HRRR AND RAP GUIDANCE INDICATE SAID FACTORS WILL BE ENOUGH
TO DEVELOP ISOLATED TO SCATTERED MOIST CONVECTION OFF THE CAPROCK
THIS AFTERNOON AND FOR THIS REASON HAVE INSERTED A SLIGHT CHANCE
OF STORMS THERE AFTER 18Z. FURTHER WEST...DRIER MID-LEVEL AIR IS
WORKING INTO THE REGION...BUT THE SFC TROUGH AND STRONG HEATING
SHOULD BE ENOUGH TO POP ADDITIONAL ISOLATED TO SCATTERED
THUNDERSTORMS THIS AFTERNOON SOMEWHERE NEAR OR JUST WEST OF THE
TX/NM LINE...WHICH WILL MOVE EASTWARD THROUGH THE EVENING HOURS
WHILE GRADUALLY WANING IN INTENSITY. FAIRLY STRONG INSTABILITY
/SBCAPES PUSHING 2000 J/KG/ AND MODEST DEEP LAYER SHEAR /GENERALLY
AOB 35 KNOTS/ COULD SUPPORT A FEW STRONG/SEVERE CELLS...THOUGH
OVERALL STORM ORGANIZATION WILL LIKELY BE LIMITED. IN ADDITION TO
THE POSSIBILITY OF DUSTY OUTFLOWS WITH ANY CONVECTION...BREEZY
SOUTHERLY WINDS WILL LIKELY RESULT IN A FAIR AMOUNT OF BLOWING
DUST AGAIN THIS AFTERNOON INTO THE EVENING...SIMILAR TO YESTERDAY.
THE REMAINDER OF THE FORECAST REMAINS IN GOOD SHAPE. UPDATE
PRODUCTS HAVE BEEN SENT.
&&
.PREV DISCUSSION... /ISSUED 638 AM CDT FRI JUN 21 2013/
AVIATION...
BREEZY SOUTH WINDS WILL GUST TO NEAR 30 KNOTS TODAY AS A SURFACE
TROUGH REMAINS IN CLOSE PROXIMITY TO BOTH TERMINALS. THEREFORE...WILL
LEAVE PREVAILING MVFR CONDITIONS IN FOR BOTH SITES FROM MID-LATE
MORNING THROUGH MID EVENING GIVEN THE LIKELIHOOD OF BLOWING DUST
AGAIN TODAY. KLBB WILL SEE A BETTER CHANCE FOR SHOWERS OR STORMS
IN THE VICINITY THAN KCDS...BUT CONFIDENCE IN COVERAGE IS NOT HIGH
ENOUGH AT THIS TIME TO WARRANT MENTION.
PREV DISCUSSION... /ISSUED 409 AM CDT FRI JUN 21 2013/
SHORT TERM...
ISOLATED SHOWERS AND EMBEDDED THUNDER WILL CONTINUE TO WANE INTO THE
EARLY MORNING HOURS. TIGHTENING SURFACE TROUGH NEAR THE NEW MEXICO
STATE LINE ALONG WITH POSITIONING BEHIND A WAKE LOW NEAR THE
INTERSTATE 40 CORRIDOR EAST OF AMARILLO HAVE KEPT WIND GUSTS IN THE
40 TO 50 MPH RANGE ON AN ABERNATHY TO FLOYDADA LINE. SHOULD SEE
THESE STRONG GUSTS EXIT TO THE NORTH AND EAST AS THE WAKE LOW MOVES
OFF IN THIS DIRECTION AND PRESSURE GRADIENT SOMEWHAT WEAKENS AWAY
FROM THE TROUGH AXIS.
SOUTHWEST FLOW REGIME WILL MAINTAIN ITSELF ALOFT TODAY AS BROAD
TROUGHING BLANKETS MUCH OF THE WESTERN CONUS WITH UPPER RIDGING
SOUTHEAST OF WEST TEXAS. FALLING PRESSURES IN CORRESPONDENCE WITH
THE ABOVE REFERENCED DEEPENING SURFACE TROUGH EXTENDING FROM THE
FRONT RANGE INTO EASTERN NEW MEXICO WILL LEAD TO THE BEST
THUNDERSTORM CHANCES ACROSS THE FAR SOUTHWEST PANHANDLE AND WESTERN
SOUTH PLAINS. RIBBON OF THETA-E VALUES WILL BE HIGHEST HERE WITH
GREATER INSTABILITY AS SUFFICIENT MOISTURE REMAINS IN PLACE WITH
DEWPOINTS IN THE UPPER 50S TO LOWER 60S.
MORE PRONOUNCED ELEVATED MIXED LAYER TO THE EAST INTO THE
ROLLING PLAINS AND EXTREME SOUTHEAST PANHANDLE WILL PRECLUDE
CONVECTIVE INITIATION...BUT A 30 TO 40 KNOT LOW LEVEL JET AND
INCREASING DEEP LAYER SHEAR TO NEAR 30 KNOTS MAY BE ENOUGH FOR
PREEXISTING ACTIVITY TO SKIRT EAST OFF THE CAPROCK. STEEP LAPSE RATES
ON EITHER SIDE OF THE ELEVATED MIXED LAYER AND RELATIVELY DRY NEAR
SURFACE AIR DUE TO TEMPERATURES IN THE 90S WILL PROMOTE LARGE HAIL
AND WIND GUSTS OF 50 TO 60 MPH IN STRONGER STORMS WEST OF THE
ESCARPMENT DURING THE AFTERNOON AND EARLY EVENING. STORMS SHOULD
WIND DOWN POST DIURNAL HEATING AND LEAVE A FEW STRAGGLING SHOWERS
MOVING TO THE NORTH AND EAST. WINDS WILL REMAIN IN THE 10 TO 15 MPH
RANGE OVERNIGHT AND COMBINE WITH RESIDUAL MOISTURE TO KEEP LOW
TEMPERATURES A FEW DEGREES ABOVE CLIMATOLOGY...RANGING FROM THE MID
TO UPPER 60S ON THE CAPROCK AND UPPER 60S TO LOW 70S IN THE ROLLING
PLAINS AND FAR SOUTHEAST PANHANDLE.
LONG TERM...
BY SATURDAY MORNING...ELONGATED UPPER LOW WILL BE POSITIONED FROM
IDAHO TO NORTHERN AB/SK WITH BROAD SOUTHWESTERLY FLOW ACROSS THE
CENTRAL STATES. HIGH WILL CONTINUE TO STRENGTHEN ACROSS THE
SOUTHEASTERN USA THOUGH THERE WILL BE A WEAKNESS OUT NEAR THE
SMOKY MTNS. THE HIGH WILL BUILD AND SHIFT EAST TO WEST BY THE
MIDDLE OF NEXT WEEK BEFORE STRENGTHENING FURTHER OVER THE FOUR
CORNERS BY LATE IN THE WEEK WITH THE PATTERN LARGELY REMAINING
STAGNANT OUT THROUGH 240 HOURS.
INDICATIONS SUGGEST THAT THE WET PATTERN ACROSS OUR WESTERN ZONES
WILL CONTINUE THROUGH AT LEAST SUNDAY WITH LESS OPPORTUNITY MONDAY
EVENING AND THEREAFTER AS PATTERN CHANGES OVERHEAD. HAVE BUMPED
POPS SAT/SUN AND TRIMMED MONDAY LEAVING THINGS DRY THEREAFTER.
TEMPERATURES WILL BE ON THE INCREASE NEXT WEEK WITH VALUES
APPROACHING THE CENTURY MARK BY MID WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 91 64 94 63 95 / 30 30 20 20 20
TULIA 91 66 93 66 94 / 20 30 20 20 20
PLAINVIEW 91 68 93 67 93 / 20 30 20 20 20
LEVELLAND 92 68 94 68 94 / 20 30 20 20 20
LUBBOCK 92 69 94 69 94 / 20 20 10 20 20
DENVER CITY 94 67 94 69 95 / 20 30 20 20 20
BROWNFIELD 93 68 94 69 94 / 20 20 20 20 20
CHILDRESS 95 70 97 70 96 / 20 20 10 10 10
SPUR 94 70 97 71 97 / 20 20 10 10 10
ASPERMONT 96 71 99 72 98 / 20 20 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
23
AREA FORECAST DISCUSSION...UPDATED
NWS SPOKANE WA
1039 PM PDT Thu Jun 20 2013
.SYNOPSIS...
Rain will continue tonight and early Friday but will decrease in
intensity and gradually subside by Friday evening. A drying and
warming trend is expected Saturday and early Sunday with the
exception of isolated mountain thunderstorms. More wet and cool
weather will arrive as early as Sunday afternoon and persist
through midweek followed by another warming, dry period to close
out the work-week.
&&
.UPDATE...
Did an update to increase chance of precipitation most locations
early this evening and then again overnight. Closed low currently
resides over southern Alberta and will retrograde west back toward
eastern WA and northern ID. HRRR model is hinting at some wrap
around precipitation currently over southeastern British Columbia
moving southwest through the evening and into the eastern Cascades
overnight. Also the area of rain currently over the basin will
slowly shift north and east through the evening and overnight
hours into extreme eastern WA and north ID. So, overall a very
wet, soggy night. Summer solstice is at 1004 tonight, and it feels
like April. /Nisbet
&&
.AVIATION...
06Z TAFS: The rain band from Spokane to Moses Lake has become
less organized tonight and will continue through tomorrow morning
as the upper support shears over the next 18 hours.
Stratus is expected to develop through the early morning
hours. Ceilings at or below 1000 feet at Spokane, Pullman, and Coeur
D`Alene seems like a good bet. Summer solstice means the most
daylight of the year, so it will be interesting to see how long we
can keep stratus. The air mass will be very moist tomorrow, but the
high sun angle should eventually break up the low cloud deck. Showers
continue through the day, but finally have no mention of rain aft
23-03Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 46 59 46 70 50 75 / 100 70 20 10 0 20
Coeur d`Alene 44 59 45 69 48 75 / 100 70 40 20 10 20
Pullman 44 59 43 69 47 74 / 70 60 50 10 10 20
Lewiston 48 65 50 76 54 81 / 50 60 40 10 0 20
Colville 46 64 45 73 47 79 / 90 50 20 20 10 20
Sandpoint 46 60 46 67 45 74 / 100 70 50 30 30 20
Kellogg 45 57 44 65 47 72 / 100 70 60 30 30 20
Moses Lake 50 71 49 79 55 81 / 100 30 10 0 0 20
Wenatchee 51 71 52 78 59 80 / 100 20 10 0 0 20
Omak 48 71 49 77 52 80 / 80 20 10 10 0 20
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1053 PM CDT SAT JUN 22 2013
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.UPDATE...
ISSUED AT 856 PM CDT SAT JUN 22 2013
HAVE UPDATED THE GRIDS/ZFP TO FOCUS HIGHEST POPS OVER OUR FAR
SOUTHERN TIER OF COUNTIES. TSTMS HAVE DEVELOPED NORTH OF THE
STATIONARY FRONT...WHICH EXTENDS ACROSS SOUTHERN WI. CURRENT
STORMS HEADED TOWARD WAUSHARA COUNTY SHOWING SOME SIGNS OF
POSSIBLE STRONG WINDS...BUT ARE BECOMING MORE ELEVATED WITH
TIME...AS SBCAPE IS DOWN TO 200 J/KG AND SBCIN IS AT OR ABOVE
150 J/KG. LOCALLY HEAVY RAINFALL LOOKS LIKE THE MAIN THREAT
OVER THE NEXT 3-5 HOURS...MAINLY SOUTH OF A LINE FROM ISW TO
MTW.
SOME WEAKER CONVECTION WAS SLOWLY EDGING TOWARD NC WI...SO
WILL HAVE CHANCE POPS SPREADING ACROSS NORTHERN WI OVERNIGHT.
A FEW MODELS ARE SUGGESTING THAT CONVECTION MAY TRY TO FILL
BACK IN OVER OUR SW COUNTIES OVERNIGHT AS THE LLJ CRANKS UP
OVER SOUTHERN MN AND SW WI IN ASSOCIATION WITH A S/W TROF
APPROACHING FROM THE PLAINS. HAVE HEDGED POPS SLIGHTLY HIGHER
IN OUR SW COUNTIES LATE TONIGHT...BUT KEPT THEM IN CHANCE
CATEGORY FOR NOW.
&&
.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 06Z TAF ISSUANCE
ISSUED AT 1046 PM CDT SAT JUN 22 2013
RAIN AND EMBEDDED TSTMS WERE OCCURRING ACROSS MUCH OF CENTRAL AND
EAST CENTRAL WI LATE THIS EVG...BUT SHOULD DIMINISH OVERNIGHT AS
THE LOW-LEVEL JET VEERS WEST. WITH THE WARM FRONT LIKELY STAYING
TO OUR SOUTH OVERNIGHT...WIDESPREAD LOW CLOUDS SHOULD REDEVELOP
OVER MOST OF THE FORECAST AREA OVERNIGHT INTO EARLY SUNDAY.
IMPROVING CONDITIONS SHOULD OCCUR BY LATE MORNING. AN UPPER LEVEL
DISTURBANCE OVER THE PLAINS WILL BRUSH THROUGH C/NC WI DURING THE
MIDDAY PERIOD ON SUNDAY...AND MAY TRIGGER SCT TSTMS AT
CWA/AUW/RHI. STORMS COULD REACH ATW/GRB LATE AFTERNOON/EARLY EVG.
CONFIDENCE IN THE DETAILS REMAINS FAIRLY LOW.
&&
.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.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE.........KIECKBUSCH
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......KIECKBUSCH
MARINE.........RDM
AREA FORECAST DISCUSSION...UPDATED
NWS GREEN BAY WI
905 PM CDT SAT JUN 22 2013
NEW INFORMATION ADDED TO UPDATE SECTION
.UPDATE...
ISSUED AT 856 PM CDT SAT JUN 22 2013
HAVE UPDATED THE GRIDS/ZFP TO FOCUS HIGHEST POPS OVER OUR FAR
SOUTHERN TIER OF COUNTIES. TSTMS HAVE DEVELOPED NORTH OF THE
STATIONARY FRONT...WHICH EXTENDS ACROSS SOUTHERN WI. CURRENT
STORMS HEADED TOWARD WAUSHARA COUNTY SHOWING SOME SIGNS OF
POSSIBLE STRONG WINDS...BUT ARE BECOMING MORE ELEVATED WITH
TIME...AS SBCAPE IS DOWN TO 200 J/KG AND SBCIN IS AT OR ABOVE
150 J/KG. LOCALLY HEAVY RAINFALL LOOKS LIKE THE MAIN THREAT
OVER THE NEXT 3-5 HOURS...MAINLY SOUTH OF A LINE FROM ISW TO
MTW.
SOME WEAKER CONVECTION WAS SLOWLY EDGING TOWARD NC WI...SO
WILL HAVE CHANCE POPS SPREADING ACROSS NORTHERN WI OVERNIGHT.
A FEW MODELS ARE SUGGESTING THAT CONVECTION MAY TRY TO FILL
BACK IN OVER OUR SW COUNTIES OVERNIGHT AS THE LLJ CRANKS UP
OVER SOUTHERN MN AND SW WI IN ASSOCIATION WITH A S/W TROF
APPROACHING FROM THE PLAINS. HAVE HEDGED POPS SLIGHTLY HIGHER
IN OUR SW COUNTIES LATE TONIGHT...BUT KEPT THEM IN CHANCE
CATEGORY FOR NOW.
&&
.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 00Z TAF ISSUANCE
ISSUED AT 628 PM CDT SAT JUN 22 2013
TSTMS WERE DEVELOPING IN SOUTHEAST MN...NORTHEAST IA AND WEST
CENTRAL AND SOUTHWEST WI LATE THIS AFTERNOON...ALONG AND NORTH OF
A WARM FRONTAL BOUNDARY. THESE SHOULD AFFECT MAINLY C/EC WI THIS
EVENING INTO EARLY SUNDAY MORNING. ALTHOUGH STRONG WINDS AND SMALL
HAIL ARE POSSIBLE...THE PRIMARY THREAT SHOULD BE TORRENTIAL
RAINFALL. MVFR CIGS WERE STILL OBSERVED AT SEVERAL LOCATIONS...
AND SUSPECT THAT LOW CLOUDS WILL BECOME MORE PREVALENT OVERNIGHT
NORTH OF THE WARM FRONT. WILL HAVE TEMPO GROUPS FOR LIFR CIGS
AT RHI/AUW/CWA LATE TONIGHT...WITH IMPROVING CONDITIONS EXPECTED
BY MID-MORNING. AN UPPER LEVEL DISTURBANCE OVER THE PLAINS WILL
BRUSH THROUGH C/NC WI DURING THE MIDDAY PERIOD ON SUNDAY...AND MAY
TRIGGER SCT TSTMS AT CWA/AUW/RHI. CONFIDENCE IN THE DETAILS REMAINS
FAIRLY LOW.
&&
.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.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE.........KIECKBUSCH
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......KIECKBUSCH
MARINE.........RDM
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
641 PM CDT SAT JUN 22 2013
UPDATED AVIATION PORTION FOR 00Z TAF 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 00Z TAF ISSUANCE
ISSUED AT 628 PM CDT SAT JUN 22 2013
TSTMS WERE DEVELOPING IN SOUTHEAST MN...NORTHEAST IA AND WEST
CENTRAL AND SOUTHWEST WI LATE THIS AFTERNOON...ALONG AND NORTH OF
A WARM FRONTAL BOUNDARY. THESE SHOULD AFFECT MAINLY C/EC WI THIS
EVENING INTO EARLY SUNDAY MORNING. ALTHOUGH STRONG WINDS AND SMALL
HAIL ARE POSSIBLE...THE PRIMARY THREAT SHOULD BE TORRENTIAL
RAINFALL. MVFR CIGS WERE STILL OBSERVED AT SEVERAL LOCATIONS...
AND SUSPECT THAT LOW CLOUDS WILL BECOME MORE PREVALENT OVERNIGHT
NORTH OF THE WARM FRONT. WILL HAVE TEMPO GROUPS FOR LIFR CIGS
AT RHI/AUW/CWA LATE TONIGHT...WITH IMPROVING CONDITIONS EXPECTED
BY MID-MORNING. AN UPPER LEVEL DISTURBANCE OVER THE PLAINS WILL
BRUSH THROUGH C/NC WI DURING THE MIDDAY PERIOD ON SUNDAY...AND MAY
TRIGGER SCT TSTMS AT CWA/AUW/RHI. CONFIDENCE IN THE DETAILS REMAINS
FAIRLY LOW.
&&
.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.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......KIECKBUSCH
MARINE.........RDM
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
631 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 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 630 PM CDT SAT JUN 22 2013
A WARM FRONT EXTENDED FROM NEAR KFBL TO NEAR KMFI WITH ANOTHER
BOUNDARY ACROSS NORTHEAST IOWA...BETWEEN KMCW AND KAUM...INTO
SOUTHWEST WISCONSIN NEAR KLNR. SCATTERED STORMS HAVE DEVELOPED
ALONG BOTH OF THESE BOUNDARIES AND ARE MOVING OFF TO THE
NORTHEAST. INITIAL ACTIVITY HAS ALREADY MOVE PAST KRST AND WITH
NOTHING DOWNSTREAM AT THIS TIME...PLAN TO START THEM WITH VCTS AND
TEMPO A SHORT PERIOD OF A STORM AT THE AIRPORT EARLY THIS EVENING.
WILL ALSO START KLSE WITH VCTS BUT CARRY A TEMPO A LITTLE LONGER
TO ACCOUNT FOR THE ACTIVITY DOWNSTREAM INTO NORTHEAST IOWA. AFTER
THE MIDDLE OF THE EVENING...UNCLEAR ON WHERE THE STORMS WILL BE
DEVELOP AS THE LOW LEVEL JET STRENGTHENS AND INTERACTS WITH THE
BOUNDARIES. STILL EXPECTING THE BOUNDARIES TO BE IN THE AREA BUT
MOVING NORTH...SO HAVE LEFT VCTS IN AND PLAN TO UPDATE IF A STORM
LOOKS TO THREATEN ONE OF THE AIRPORTS. WILL CONTINUE WITH THE
PREVIOUS THINKING THAT THE BOUNDARIES WILL BE NORTH OF THE TAF
SITES BY LATE TONIGHT INTO SUNDAY WITH ANY CONVECTION ALSO NORTH
OF THE AREA. COULD ONCE AGAIN SEE MORE STORMS DEVELOP LATE SUNDAY
AFTERNOON BUT WITH LOW CONFIDENCE ON THIS...WILL PLAN TO ADDRESS
THIS WITH THE NEXT SET OF FORECASTS.
&&
.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...04
HYDROLOGY...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
355 PM CDT FRI JUN 21 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 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1150 AM CDT FRI JUN 21 2013
DIFFICULT FORECAST FOR SHRA/TS CHANCES AS VARIOUS SFC
BOUNDARIES...UPPER AIR DISTURBANCES...AND POSITIONING OF THE LOW
LEVEL MOISTURE TRANSPORT ARE ALL GOING TO HAVE A HAND IN WHERE PCPN
DEVELOPS. GIVEN THIS SCENARIO...CONFIDENCE IS LOW IN PINPOINTING THE
SHRA/TS CHANCES OUTSIDE OF A 6 HOUR WINDOW.
THAT SAID...WEST-EAST RUNNING SFC BOUNDARY IS JUST SOUTH OF THE
KRST/KLSE LATE THIS MORNING...AND IS SLATED TO EITHER LINGER THERE
OR MOVE JUST A BIT NORTH. SHRA/TS COULD FIRE ALONG THE BOUNDARY
LATER THIS AFTERNOON...ALTHOUGH LOOKS ISOLD AT THIS TIME. BETTER
CHANCES WILL COME LATER TONIGHT AS A THUNDERSTORM COMPLEX IS
EXPECTED TO DEVELOP OVER THE NORTHERN PLAINS...ROLLING EAST ACROSS
THE REGION TONIGHT. MODELS GENERALLY FAVOR KEEPING IT NORTH
OF I-90...BUT COULD IMPACT KRST/KLSE. AGAIN...WITH CONFIDENCE NOT
HIGH IN TIMING/POSITIONING OF LIKELY CONVECTIVE COMPLEXES...WILL
STAY WITH VCTS/VCSH MENTION. TAFS WILL BE UPDATED AS TRENDS BECOME
CLEARER.
&&
.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 FROM 9 PM CDT THIS EVENING THROUGH SATURDAY
MORNING FOR WIZ017-029-032>034-041>044-053>055-061.
MN...FLASH FLOOD WATCH FROM 9 PM CDT THIS EVENING THROUGH SATURDAY
MORNING FOR MNZ079-086>088-094>096.
IA...FLASH FLOOD WATCH FROM 9 PM CDT THIS EVENING THROUGH SATURDAY
MORNING FOR IAZ008>011-018-019-029-030.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION.....RIECK
HYDROLOGY...BOYNE
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1243 PM CDT FRI JUN 21 2013
.UPDATE...MCC CONTINUES HEADING SOUTHEAST AT STEADY PACE. LEADING
EDGE OF SQUALL THAT HAS RECENTLY BEEN PRODUCING 25-35 KNOT GUSTS
IS OVER RACINE/KENOSHA IS NOW OFFSHORE.
LOCAL WAKE LOW PARAMETER SUGGESTS POTENTIAL FOR 40-50 MPH GUSTS
ALONG BACK EDGE OF PRECIPITATION CURRENTLY FROM SAUK TO FOND DU
LAC COUNTIES. HAVE RECENTLY SEEN GUSTS TO 34 KNOTS AT KDLL...33
KNOTS AT KFLD...AND 32 KNOTS AT KOSH. HAVE 35 KNOT GUSTS IN THE
NEXT COUPLE HOURS OF GRIDS ACROSS NORTHERN TWO TIERS OF COUNTIES.
HRRR AND LOCAL WSWRF 4KM ARW CORE SHOW THAT IT GETS QUIET FROM
EARLY AFTERNOON INTO THIS EVENING...IN THE WAKE OF THE MCC. CHANCE
POPS AFTER MIDNIGHT...BUT WITH LOW LEVEL JET FOCUSED WELL WEST IT
SEEMS THAT WARM ADVECTION STORMS OVER TOP OF COLD POOL FROM MCS
MAY BE HARDER TO ACHIEVE. CONSENSUS HAS CHANCE POPS AFTER
MIDNIGHT...AND THAT LOOKS GOOD AS REMNANTS OF SD MCS TRY AND MAKE
THEIR WAY INTO THE RIDGE AXIS LATE.
CRAVEN
&&
.AVIATION/18Z TAFS/...LINGERING SHOWERS AND STORMS WITH SOME
IFR/MVFR VISIBILITIES WILL DIMINISH OVER THE NEXT HOUR OR SO
ACROSS TAF SITES. DRY CONDITIONS ARE THEN EXPECTED THROUGH THE
REST OF THIS AFTERNOON AND INTO THIS EVENING...WITH VFR
CONDITIONS.
GUSTY SOUTH TO SOUTHEAST WINDS OF 20 KNOTS SUSTAINED WITH GUSTS TO
AROUND 35 KNOTS ARE EXPECTED AT MADISON AND POSSIBLY THE EASTERN
SITES THROUGH 19Z TO 20Z THIS AFTERNOON. LEFT GUSTS TO AROUND 20
KNOTS IN THE EASTERN SITES FOR NOW...DUE TO LOW CONFIDENCE WITH
THE HIGHER GUSTS THERE. GUSTS SHOULD LOWER BY LATER THIS
AFTERNOON.
LEFT VFR CONDITIONS GOING THROUGH TONIGHT AND SATURDAY...AS
THUNDERSTORM CHANCES LINGER BUT LOW CONFIDENCE IN TIMING AND
PLACEMENT OF STORMS. MAY SEE MVFR VISIBILITIES WITH LIGHT FOG AT
SITES BETWEEN 09Z AND 14Z SATURDAY. MODEST SOUTH WINDS SHOULD
LINGER LATER TONIGHT INTO SATURDAY.
WOOD
&&
.PREV DISCUSSION... /ISSUED 308 AM CDT FRI JUN 21 2013/
TODAY AND TONIGHT...FORECAST CONFIDENCE MEDIUM.
THIS WARM...MOIST AND UNSTABLE SOUTHWESTERLY FLOW REGIME IS
TYPICALLY DIFFICULT TO RESOLVE DETAILED CONVECTIVE TRENDS BEYOND
ABOUT 12HRS. CONVECTION BEYOND 12HRS DEPENDS HIGHLY ON THE BEHAVIOR
OF CONVECTION IN THE PRECEDING 12HRS. FOR INSTANCE...ALL THE HI
RESOLUTION SHORT RANGE MODELS ARE HAVING DIFFICULTY WITH THE
CONVECTION OVER MN EARLY THIS MORNING. EARLIER MODEL RUNS DEVELOPED
THIS INTO A BIG BOW ECHO THAT RACED ACROSS THE FORECAST AREA AROUND
12Z. THE REALITY IS THAT IT IS STAYING UP TO THE NORTH MUCH LONGER
AND MAY END UP JUST SKIRTING THE NORTHERN FORECAST AREA BEFORE
DIMINISHING WITH TYPICAL DIURNAL TRENDS. THE TURN TO THE SOUTHEAST
NEEDS THE COLD POOL DYNAMICS TO GET ORGANIZED AND THAT APPEARS TO BE
HAPPENING AROUND 07Z THIS MORNING. EACH HRRR RUN HAS BEEN BACKING
OFF ON THE SPEED AND OVERALL DEVELOPMENT. THE NOSE OF THE LOW LEVEL
JET AND BEST INSTABILITY ARE TO THE WEST AND NORTH...BUT WILL LEAN
NORTHEAST INTO THE AREA TODAY. THE MODELS CONTINUE TO BE TOO BULLISH
ON SFC MOISTURE. FOR NOW...THERE DOES SEEM TO BE A CONSENSUS THAT WE
WILL LIKELY SEE THE MN CONVECTION ROLL ACROSS THE AREA THIS MORNING
AS THE LOW LEVEL JET AND MOISTURE LEAN INTO THE AREA. THIS SHOULD
LAY OUT A LOW LEVEL BAROCLINIC ZONE THAT COULD BE THE FOCUS FOR MORE
CONVECTION LATER THIS AFTERNOON. WE SHOULD SEE ANOTHER MCS DEVELOP
OUT IN THE PLAINS THIS AFTERNOON AND ROLL INTO THE CWA LATER
TONIGHT. SO LONG STORY SHORT...LOOK FOR MORNING CONVECTION TO
DIMINISH THIS AFTERNOON WITH ANOTHER ROUND LATE TONIGHT INTO
SATURDAY MORNING. TEMPS MIGHT BE HELD DOWN A BIT TODAY IF WE ARE
SLOW TO SCOUR OUT THE MORNING CONVECTIVE DEBRIS. TEMPS WON/T DROP
TOO FAR TONIGHT AS WE ARE SOLIDLY IN THE WARM SECTOR.
SATURDAY THROUGH SUNDAY NIGHT...FORECAST CONFIDENCE MEDIUM TO HIGH.
PRECIP CHANCES CONTINUE TO EXIST EARLY ON THIS PERIOD EVEN THOUGH
500 HPA SHORT WAVE TROUGHS TRAVERSE MAINLY TO OUR NORTH AND WEST.
CWA CONTINUES TO LIE UNDER A MID-LEVEL RIDGE WITH SHORT WAVE TROUGHS
RIDING THROUGH. THE NOCTURNAL LLJ MAINLY FOCUSES ON SOUTHWEST AND
WEST CENTRAL WISCONSIN...PEAKING SATURDAY NIGHT. MODELS DO SHOW
LOW-LEVEL WAA AT THIS TIME...BUT WAA MORE PERSISTENT AND STRONGER
OUTSIDE THE CWA. FURTHER...ALTHOUGH SOME SYNOPTIC LIFT WILL BE
PRESENT IN THE PERIOD...THE THERMODYNAMIC ENVIRONMENT WILL NOT BE
THAT PRIMED. BUFKIT SOUNDINGS AND LOW-LEVEL THERMO ENVIRONMENT SHOW
A CAPPED ENVIRONMENT COINCIDING WITH LOW-LEVEL THERMAL RIDGE. THIS
COULD POTENTIALLY LIMIT OUR THUNDER CHANCES THIS WEEKEND.
OTHERWISE...AMPLE MEAN LAYER INSTABILITY IN THE PERIOD WILL COMBINE
WITH SUFFICIENT MOISTURE...ESPECIALLY CONSIDERING SFC DEW POINTS
FCST IN THE UPPER 60S TO AROUND 70 DURING THE DAY SAT AND SUN. SHEAR
WILL BE A LIMITING FACTOR THOUGH FOR ANY ORGANIZED DEVELOPMENT IN
THE PERIOD. DEEP LAYER 0-6KM SHEAR IS ONLY AROUND 15-25 KTS. THIS
SUGGEST ORDINARY THUNDERSTORMS AND SOME MULTICELL ORGANIZATION TYPE
STORM MODES. SATURDAY IS EXPECTED TO GIVE THE CWA THE BEST CHANCE
FOR CONVECTION GIVEN THE BETTER INSTABILITY AND PROXIMITY OF THE
EFFECTIVE BOUNDARY. THOUGH GIVEN THE AFOREMENTIONED CAP AND THE
UNCERTAIN POSITION OF THE BOUNDARY...CONTINUED WITH CHANCES ON
SATURDAY.
WARM AND ABOVE NORMAL HIGHS EXPECTED SATURDAY AND SUNDAY. MODEL
CONSENSUS OF 925 HPA TEMPS ARE AROUND 25-27 C SAT AND 24-26 C SUN
THAT CORRESPOND TO 89-93 F AND 87-91 F...RESPECTIVELY. NOTE...WILL
HAVE TO WATCH APPARENT TEMPS/HEAT INDEX VALUES SUNDAY GIVEN THE
MOIST SFC DEW POINTS IN THE UPPER 60S/AROUND 70 AND SFC HIGHS AROUND
90 IN PORTIONS OF THE CWA...AS HEAT INDEX VALUES REACH LOW AND MID
90S SAT AND WELL INTO THE MID AND UPPER 90S SUN. POTENTIAL RISK OF
HEAT INDEX VALUES FURTHER SUBSTANTIATED BY LOOKING AT CIPS IMPACT
BASED GUIDANCES PROBABILITY OF SFC HEAT INDEX VALUES EXCEEDING
95 F THAT HAS HIGH PROBS IN SOUTH CENTRAL AND SOUTHEAST WI.
MONDAY THROUGH THURSDAY NIGHT...FORECAST CONFIDENCE MEDIUM.
PERIOD CHARACTERIZED GENERALLY BY A MID-LEVEL ZONAL FLOW...THAT
BREAKS DOWN LATE THURSDAY INTO FRIDAY AS A MORE AMPLIFIED PATTERN
TAKES OVER. THE LATTER SHARED BY BOTH THE GFS AND ECMWF. VARIOUS S/W
TROUGHS MOVE THROUGH THOUGH DIFFERENCES BETWEEN FEATURES AND TIMING
MAKE FCST UNCERTAIN. THE GENERAL SW FLOW AND THERMAL ENVIRONMENT
THOUGH SHOULD KEEP READINGS NEAR OR ABOVE THEIR SEASONAL NORMAL
VALUES. SEASONAL NORMAL VALUES THIS TIME OF THE YEAR ARE USUALLY
AROUND 81-82 TO 78-79 WEST TO EAST ACROSS THE CWA. BY THURSDAY INTO
FRIDAY WITH A LONG WAVE TROUGH DIGGING INTO THE GREAT LAKES
REGION...FLOW BECOMES MORE OUT OF THE NW-N AND HIGH TEMPERATURES
BEGIN TRENDING DOWNWARD.
AVIATION/12Z TAFS/...MAIN AVIATION CONCERN DURING THE PERIOD IS
TIMING OF ANY CONVECTION...AND THAT WILL BE CHALLENGING.
OVERALL...CONDITIONS SHOULD BE VFR. THE EXCEPTION WILL BE IN AND
AROUND ANY THUNDERSTORMS WHERE VSBY AND CIGS COULD BRIEFLY DROP TO
MVFR LEVELS. WE SHOULD SEE STORMS MOVE THROUGH THE AREA THIS
MORNING...AS THE REMNANTS OF STORMS UP TO OUR NORTHWEST EARLY THIS
MORNING ROLL SOUTHEAST THROUGH THE AREA. THERE SHOULD BE A BREAK IN
THE ACTIVITY THIS AFTERNOON...BUT CAN/T RULE OUT NEW DEVELOPMENT
ALONG ANY REMNANT OUTFLOW/BAROCLINIC BOUNDARIES DURING THE HEAT OF
THE AFTERNOON. THE NEXT BEST CHANCE FOR STORMS WOULD BE LATER
TONIGHT AS ANOTHER LARGE COMPLEX OF STORMS THAT DEVELOPS UPSTREAM
EARLIER IN THE AFTERNOON ROLLS IN.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...CRAVEN/WOOD
TODAY/TONIGHT AND AVIATION/MARINE...DAVIS
SATURDAY THROUGH THURSDAY...ET
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
308 AM CDT FRI JUN 21 2013
.TODAY AND TONIGHT...FORECAST CONFIDENCE MEDIUM.
THIS WARM...MOIST AND UNSTABLE SOUTHWESTERLY FLOW REGIME IS
TYPICALLY DIFFICULT TO RESOLVE DETAILED CONVECTIVE TRENDS BEYOND
ABOUT 12HRS. CONVECTION BEYOND 12HRS DEPENDS HIGHLY ON THE BEHAVIOR
OF CONVECTION IN THE PRECEDING 12HRS. FOR INSTANCE...ALL THE HI
RESOLUTION SHORT RANGE MODELS ARE HAVING DIFFICULTY WITH THE
CONVECTION OVER MN EARLY THIS MORNING. EARLIER MODEL RUNS DEVELOPED
THIS INTO A BIG BOW ECHO THAT RACED ACROSS THE FORECAST AREA AROUND
12Z. THE REALITY IS THAT IT IS STAYING UP TO THE NORTH MUCH LONGER
AND MAY END UP JUST SKIRTING THE NORTHERN FORECAST AREA BEFORE
DIMINISHING WITH TYPICAL DIURNAL TRENDS. THE TURN TO THE SOUTHEAST
NEEDS THE COLD POOL DYNAMICS TO GET ORGANIZED AND THAT APPEARS TO BE
HAPPENING AROUND 07Z THIS MORNING. EACH HRRR RUN HAS BEEN BACKING
OFF ON THE SPEED AND OVERALL DEVELOPMENT. THE NOSE OF THE LOW LEVEL
JET AND BEST INSTABILITY ARE TO THE WEST AND NORTH...BUT WILL LEAN
NORTHEAST INTO THE AREA TODAY. THE MODELS CONTINUE TO BE TOO BULLISH
ON SFC MOISTURE. FOR NOW...THERE DOES SEEM TO BE A CONSENSUS THAT WE
WILL LIKELY SEE THE MN CONVECTION ROLL ACROSS THE AREA THIS MORNING
AS THE LOW LEVEL JET AND MOISTURE LEAN INTO THE AREA. THIS SHOULD
LAY OUT A LOW LEVEL BAROCLINIC ZONE THAT COULD BE THE FOCUS FOR MORE
CONVECTION LATER THIS AFTERNOON. WE SHOULD SEE ANOTHER MCS DEVELOP
OUT IN THE PLAINS THIS AFTERNOON AND ROLL INTO THE CWA LATER
TONIGHT. SO LONG STORY SHORT...LOOK FOR MORNING CONVECTION TO
DIMINISH THIS AFTERNOON WITH ANOTHER ROUND LATE TONIGHT INTO
SATURDAY MORNING. TEMPS MIGHT BE HELD DOWN A BIT TODAY IF WE ARE
SLOW TO SCOUR OUT THE MORNING CONVECTIVE DEBRIS. TEMPS WON/T DROP
TOO FAR TONIGHT AS WE ARE SOLIDLY IN THE WARM SECTOR.
SATURDAY THROUGH SUNDAY NIGHT...FORECAST CONFIDENCE MEDIUM TO HIGH.
PRECIP CHANCES CONTINUE TO EXIST EARLY ON THIS PERIOD EVEN THOUGH
500 HPA SHORT WAVE TROUGHS TRAVERSE MAINLY TO OUR NORTH AND WEST.
CWA CONTINUES TO LIE UNDER A MID-LEVEL RIDGE WITH SHORT WAVE TROUGHS
RIDING THROUGH. THE NOCTURNAL LLJ MAINLY FOCUSES ON SOUTHWEST AND
WEST CENTRAL WISCONSIN...PEAKING SATURDAY NIGHT. MODELS DO SHOW
LOW-LEVEL WAA AT THIS TIME...BUT WAA MORE PERSISTENT AND STRONGER
OUTSIDE THE CWA. FURTHER...ALTHOUGH SOME SYNOPTIC LIFT WILL BE
PRESENT IN THE PERIOD...THE THERMODYNAMIC ENVIRONMENT WILL NOT BE
THAT PRIMED. BUFKIT SOUNDINGS AND LOW-LEVEL THERMO ENVIRONMENT SHOW
A CAPPED ENVIRONMENT COINCIDING WITH LOW-LEVEL THERMAL RIDGE. THIS
COULD POTENTIALLY LIMIT OUR THUNDER CHANCES THIS WEEKEND.
OTHERWISE...AMPLE MEAN LAYER INSTABILITY IN THE PERIOD WILL COMBINE
WITH SUFFICIENT MOISTURE...ESPECIALLY CONSIDERING SFC DEW POINTS
FCST IN THE UPPER 60S TO AROUND 70 DURING THE DAY SAT AND SUN. SHEAR
WILL BE A LIMITING FACTOR THOUGH FOR ANY ORGANIZED DEVELOPMENT IN
THE PERIOD. DEEP LAYER 0-6KM SHEAR IS ONLY AROUND 15-25 KTS. THIS
SUGGEST ORDINARY THUNDERSTORMS AND SOME MULTICELL ORGANIZATION TYPE
STORM MODES. SATURDAY IS EXPECTED TO GIVE THE CWA THE BEST CHANCE
FOR CONVECTION GIVEN THE BETTER INSTABILITY AND PROXIMITY OF THE
EFFECTIVE BOUNDARY. THOUGH GIVEN THE AFOREMENTIONED CAP AND THE
UNCERTAIN POSITION OF THE BOUNDARY...CONTINUED WITH CHANCES ON
SATURDAY.
WARM AND ABOVE NORMAL HIGHS EXPECTED SATURDAY AND SUNDAY. MODEL
CONSENSUS OF 925 HPA TEMPS ARE AROUND 25-27 C SAT AND 24-26 C SUN
THAT CORRESPOND TO 89-93 F AND 87-91 F...RESPECTIVELY. NOTE...WILL
HAVE TO WATCH APPARENT TEMPS/HEAT INDEX VALUES SUNDAY GIVEN THE
MOIST SFC DEW POINTS IN THE UPPER 60S/AROUND 70 AND SFC HIGHS AROUND
90 IN PORTIONS OF THE CWA...AS HEAT INDEX VALUES REACH LOW AND MID
90S SAT AND WELL INTO THE MID AND UPPER 90S SUN. POTENTIAL RISK OF
HEAT INDEX VALUES FURTHER SUBSTANTIATED BY LOOKING AT CIPS IMPACT
BASED GUIDANCES PROBABILITY OF SFC HEAT INDEX VALUES EXCEEDING
95 F THAT HAS HIGH PROBS IN SOUTH CENTRAL AND SOUTHEAST WI.
MONDAY THROUGH THURSDAY NIGHT...FORECAST CONFIDENCE MEDIUM.
PERIOD CHARACTERIZED GENERALLY BY A MID-LEVEL ZONAL FLOW...THAT
BREAKS DOWN LATE THURSDAY INTO FRIDAY AS A MORE AMPLIFIED PATTERN
TAKES OVER. THE LATTER SHARED BY BOTH THE GFS AND ECMWF. VARIOUS S/W
TROUGHS MOVE THROUGH THOUGH DIFFERENCES BETWEEN FEATURES AND TIMING
MAKE FCST UNCERTAIN. THE GENERAL SW FLOW AND THERMAL ENVIRONMENT
THOUGH SHOULD KEEP READINGS NEAR OR ABOVE THEIR SEASONAL NORMAL
VALUES. SEASONAL NORMAL VALUES THIS TIME OF THE YEAR ARE USUALLY
AROUND 81-82 TO 78-79 WEST TO EAST ACROSS THE CWA. BY THURSDAY INTO
FRIDAY WITH A LONG WAVE TROUGH DIGGING INTO THE GREAT LAKES
REGION...FLOW BECOMES MORE OUT OF THE NW-N AND HIGH TEMPERATURES
BEGIN TRENDING DOWNWARD.
&&
.AVIATION/12Z TAFS/...MAIN AVIATION CONCERN DURING THE PERIOD IS
TIMING OF ANY CONVECTION...AND THAT WILL BE CHALLENGING.
OVERALL...CONDITIONS SHOULD BE VFR. THE EXCEPTION WILL BE IN AND
AROUND ANY THUNDERSTORMS WHERE VSBY AND CIGS COULD BRIEFLY DROP TO
MVFR LEVELS. WE SHOULD SEE STORMS MOVE THROUGH THE AREA THIS
MORNING...AS THE REMNANTS OF STORMS UP TO OUR NORTHWEST EARLY THIS
MORNING ROLL SOUTHEAST THROUGH THE AREA. THERE SHOULD BE A BREAK IN
THE ACTIVITY THIS AFTERNOON...BUT CAN/T RULE OUT NEW DEVELOPMENT
ALONG ANY REMNANT OUTFLOW/BAROCLINIC BOUNDARIES DURING THE HEAT OF
THE AFTERNOON. THE NEXT BEST CHANCE FOR STORMS WOULD BE LATER
TONIGHT AS ANOTHER LARGE COMPLEX OF STORMS THAT DEVELOPS UPSTREAM
EARLIER IN THE AFTERNOON ROLLS IN.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...DAVIS
SATURDAY THROUGH THURSDAY...ET
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
214 AM CDT FRI JUN 21 2013
.SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT)
ISSUED AT 214 AM CDT FRI JUN 21 2013
AS SOUTHWEST UPPER FLOW CONTINUES TO ADVECT WARM AIR AND MOISTURE
INTO UPPER MIDWEST...FORECAST CHALLENGE REMAINS TIMING MESOSCALE
CONVECTIVE COMPLEXES. SEEMS LIKE A DIFFICULT TASK AT TIMES ONLY A
FEW HOURS OUT.
UPPER LOW CONTINUES TO SPIN OVER NORTHWEST U.S. WITH LARGE WESTERN
CONUS TROUGH. STEADY LOW LEVEL JET EARLY THIS MORNING AROUND 45 KTS
IS FUELING LARGE CONVECTIVE SYSTEM OVER CENTRAL MINNESOTA. CELLS
STARTED OVERNIGHT A BIT MORE DISCRETELY BUT AS COLD POOL HAS BEEN
DEVELOPING...MORE OF A LINEAR STRUCTURE UNFOLDING WHICH MAY CONTINUE
BUILDING SOUTHEAST ALONG WELL DEFINED WARM FRONT OR BOUNDARY INTO
AREA BEFORE DAYBREAK. LOWER MIXED LAYER CAPE VALUES AND LOWER SHEAR
WOULD SUGGEST SYSTEM COULD WEAKEN AS IT APPROACHES WISCONSIN BUT
WILL HAVE TO MONITOR THIS...WHICH COULD INCLUDE A FEW WARNINGS. HAVE
ALSO BEEN TRACKING BAND OF CONVECTION ACROSS WESTERN WISCONSIN THAT
SEEM TO DEVELOP ALONG MID LEVEL NOSE OF WARMER AIR BUT SEEMS
UNLIKELY THESE WOULD UPSCALE INTO ANYTHING OF SIGNIFICANCE.
MESOSCALE MODELS AND SHORT TERM MODELS CONTINUE TO CHANGE NEARLY AS
QUICKLY AS RADAR IMAGERY WHICH HURTS ANY CONFIDENCE IN THIS
FORECAST. WITH BASIC UPPER AIR PATTERN CHANGING LITTLE...HAVE BEEN
TRYING TO TIME THINGS BASED ON BEST SIGNALS OF MOISTURE TRANSPORT.
THIS TENDS TO INCREASE ACROSS OUR AREA NEXT 48 HOURS SO EXPECT
GRADUAL TREND IN CONVECTIVE SYSTEM DEVELOPMENT ZONE FROM DAKOTAS AND
WESTERN MINNESOTA CLOSER TO UPPER MISSISSIPPI RIVER AREA GOING INTO
WEEKEND. THIS SHOULD BOOST RAIN THREAT AS WELL...BUT EXACTLY WHEN IS
DIFFICULT. PLENTY OF CAPE TO WORK WITH ALTHOUGH DEEPER SHEAR DOES
REMAIN FURTHER NORTHWEST...CLOSER TO DYNAMICS. COULD SEE A BREAK IN
ACTION LATER TODAY BEFORE ADDITIONAL DEVELOPMENT TAKES PLACE AROUND
RIDGE HEADING INTO FRIDAY NIGHT. SAME PATTERN COULD KEEP GOING INTO
SUNDAY NIGHT.
REPEAT ROUNDS OF CONVECTION COULD ALSO LEAD TO PROBLEMATIC FLOOD
THREAT BUT GIVEN UNCERTAINTY OF TRACKS OF THESE SYSTEMS...WILL HAVE
TO MONITOR SHORT TERM CONDITIONS FOR ANY SPECIFIC FOCUS AREAS.
TEMPERATURES SHOULD REMAIN FAIRLY PERSISTENT FROM DAY TO DAY WITH
SUBTLE CHANGES DEPENDING ON HOW MUCH CLOUD DEBRIS IMPACTS HIGHS. DID
DROP HIGHS TODAY NORTH AND EAST OF LA CROSSE WHERE CONFIDENCE IN
CLOUD SHIELD INTO AFTERNOON IS HIGHEST. WARMEST LOW LEVEL
TEMPERATURES COME IN OVER WEEKEND SO DID BOOST HIGHS A FEW DEGRESS.
IN ADDITION...DEW POINTS DID NOT RESPOND AS QUICKLY AS EXPECTED ON
THURSDAY...PERHAPS DUE TO RECENT DRY WEATHER...SOURCE REGION OF
AIRMASS...AND IMMATURE CROPS. SCALE BACK CLIMB OF DEW POINTS ANOTHER
24 HOURS BUT OVER TIME AS MORE SOUTHWEST FLOW DEVELOPS...EXPECT THE
LOWER 70 DEGREE DEW POINTS TO ADVECT INTO AREA WITH MUGGY CONDITIONS
BEFORE WEEKEND ENDS. THIS COULD BOOST HEAT INDEX VALUES INTO 95 TO
100 DEGREES AT PEAK HEATING DURING MID TO LATE AFTERNOONS.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 214 AM CDT FRI JUN 21 2013
LATER FORECAST PERIODS WILL INVOLVE PATTERN SHIFT AS HEIGHTS RISE IN
THE WESTERN CONUS. UPPER LOW OVER NORTHWEST...OR ROUNDS OF SHORT
WAVE ENERGY...WILL EVENTUALLY SHIFT ALONG NORTHERN TIER OF STATES OR
FAR SOUTHERN CANADA AS NORTHWEST FLOW DEVELOPS INTO WESTERN GREAT
LAKES.
AS RIDGE AHEAD OF TROUGH BREAKS DOWN...COULD SEE BOUNDARY EVENTUALLY
SHIFT SOUTH THROUGH AREA WITH EVEN MORE CHANCES OF CONVECTION WELL
INTO EARLY NEXT WEEK. EXPECT COOLING TREND IN THIS SCENARIO AS WELL
BUT COULD BE MORE GRADUAL THAN A SHARP COLD FRONT.
MEDIUM RANGE GUIDANCE SUGGESTS SHORT WAVE TROUGH COULD DROP THROUGH
IN DEVELOPING NORTHWEST FLOW LATE WEDNESDAY INTO THURSDAY MORNING
COULD SPARK YET MORE RAIN SHOWERS BEFORE DRIER...NORTHWEST REGIME
SETS UP AS WESTERN MEAN RIDGE BUILDS TO CLOSE OUT THE MONTH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1138 PM CDT THU JUN 20 2013
COMPLEX OF STORMS OVER NORTHWEST MINNESOTA INTO EASTERN NORTH
DAKOTA HAS YET TO FORM INTO A LINE AND START MOVING MOVING EAST AS
EARLIER DEPICTED BY SEVERAL MODELS. THE 21.02Z HRRR NOW SUGGESTS
THAT THIS COMPLEX OF STORMS WILL NEVER GET HERE BUT RATHER STAY
NORTH OF THE WARM FRONT THAT EXTENDS ACROSS CENTRAL MINNESOTA INTO
NORTHERN WISCONSIN. RATHER...ADDITIONAL DEVELOPMENT IS EXPECTED TO
OCCUR SOUTH OF THE BOUNDARY IN THE LOW LEVEL JET AND MOISTURE
TRANSPORT AXIS OVER SOUTHERN MINNESOTA INTO NORTHERN IOWA. SOME
INDICATIONS THAT THIS IS OCCURRING WITH RECENT DEVELOPMENT OVER
SOUTHERN MINNESOTA. THE HRRR THEN CONTINUES TO EXPAND THIS THROUGH
THE NIGHT AND BRINGS IT INTO THE AREA LATE. HAVE THUS CONTINUED
THE TRENDS OF THE PREVIOUS FORECASTS BUT PUSHED THE TIMING BACK
JUST A LITTLE. COULD STILL SEE SOME GUSTY WINDS AND MVFR
VISIBILITY RESTRICTIONS SO MAINTAINED THOSE TRENDS AS WELL. STILL
EXPECTING THE ACTIVITY TO CLEAR THE AREA BY THE MIDDLE OF FRIDAY
MORNING WITH LITTLE CHANCE OF ANYTHING AFTER THAT FOR THE
REMAINDER OF THE PERIOD WITH THE NEXT ROUND OF STORMS REMAINING
WELL OFF TO THE WEST THROUGH 22.06Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...SHEA
LONG TERM....SHEA
AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1138 PM CDT THU JUN 20 2013
.SHORT TERM...(TONIGHT THROUGH SUNDAY)
ISSUED AT 316 PM CDT THU JUN 20 2013
MAIN FORECAST CONCERNS ARE PRECIPITATION CHANCES AND POTENTIAL
SEVERE WITH THUNDERSTORMS THROUGH PERIOD.
LATEST WATER VAPOR SATELLITE IMAGERY SHOWING WEAK SHORTWAVE TROUGH
LIFTING NORTHEAST INTO NORTH CENTRAL WISCONSIN AND A SERIES OF
SHORTWAVE TROUGHS OVER LAKE SUPERIOR WESTWARD TO NORTH DAKOTA. LATEST
MOSAIC RADAR INDICATES SHOWERS AND THUNDERSTORMS ACROSS NORTHERN
WISCONSIN INTO EASTERN NORTH DAKOTA. THIS IS IN RESPONSE TO 925-850MB
MOISTURE TRANSPORT AND NOSE OF LOW LEVEL JET PER 20.15Z RAP.
THE 20.12Z GFS/NAM CONTINUE TO BE IN GOOD AGREEMENT IN CARVING
UPPER LEVEL TROUGH OVER THE WESTERN UNITED STATES AND EJECTING
OUT A SERIES OF SHORTWAVE TROUGHS EMBEDDED IN SOUTHWESTERLY
FLOW ALOFT INTO THE NORTHERN PLAINS AND UPPER GREAT LAKES
REGION OVER THE NEXT SEVERAL DAYS. BIGGEST DIFFERENCES REMAIN ARE
THE TIMING AND PLACEMENT OF THE SHORTWAVE TROUGHS OVER
THE UPPER GREAT LAKES REGION THROUGH THE PERIOD. THE DETERMINISTIC
MODELS ARE OKAY IN AGREEMENT WITH SURFACE FRONT PLACEMENT THROUGH 12Z
SATURDAY...THEN THE 20.12Z NAM PUSHES SURFACE FRONT FARTHER SOUTH
THAN THE GFS. CONFIDENCE IN FORECAST BEGINS TO LOWER AFTER 12Z
SATURDAY.
TONIGHT INTO FRIDAY...THE 20.12Z GFS/NAM AND 20.15Z RAP ALL
INDICATING DECENT 925-850MB MOISTURE TRANSPORT AND LOW LEVEL JET TO
INCREASE THIS EVENING OVER FORECAST AREA. WITH A SERIES OF SHORTWAVE
TROUGHS OVER THE NORTHERN PLAINS...HIGH RESOLUTION MODELS OF THE
20.12Z SPC WRF...20.12Z ARW-EAST AND 20.16Z HRRR SHOW A COMPLEX OF
THUNDERSTORMS OVER EASTERN NORTH DAKOTA AND NORTHERN SOUTH DAKOTA
ON THE NOSE OF THE LOW LEVEL JET/925-850MB MOISTURE TRANSPORT...TO
MOVE EAST-SOUTHEAST INTO THE NORTHERN PORTIONS OF THE FORECAST AREA
AROUND 09Z TO 12Z. THE 20.12Z GFS/NAM INDICATE SOME SORT OF COMPLEX
OF THUNDERSTORMS TO TRACK INTO THE NORTHERN PORTIONS OF THE FORECAST
AREA. CONFIDENCE IS INCREASING A COMPLEX OF THUNDERSTORMS WILL MOVE
INTO THE NORTHERN PORTIONS OF THE FORECAST AREA. SEVERE POTENTIAL
STILL EXIST WITH THE 20.12Z GFS/NAM SHOW 0-3KM SHEAR OF 25-35 KNOTS
AND 0-6KM MOST UNSTABLE CAPE OF 1000-2000 J/KG OVER NORTHERN
PORTIONS OF FORECAST AREA 06Z-12Z FRIDAY. THE COMPLEX OF STORMS
SHOULD DEVELOP INTO A LINE/SQUALL LINE OF STORMS OVERNIGHT AND HAVE
THE POTENTIAL FOR DAMAGING WINDS ACROSS THE NORTHERN PORTIONS OF THE
FORECAST AREA.
FRIDAY NIGHT INTO SUNDAY...ACTIVE WEATHER PATTERN CONTINUES...AS
THE 20.12Z GFS/NAM CONTINUE TO INDICATE A SERIES OF SHORTWAVE
TROUGHS TO MOVE INTO THE UPPER MIDWEST AND UPPER GREAT LAKES
REGION. THE 20.12Z GFS/NAM CONTINUE TO HAVE DIFFERENCES IN TIMING
AND PLACEMENT OF THE SHORTWAVE TROUGHS/SURFACE FRONT ACROSS THE
UPPER MIDWEST AND GREAT LAKES REGION. THE DETERMINISTIC MODELS DO
SHOW 20 TO 30 KNOTS OF 0-3KM WIND SHEAR AND ELEVATED CAPE OF A 2000-
3000 J/KG FRIDAY THROUGH 06Z SATURDAY. POTENTIAL IS THERE FOR
THUNDERSTORMS TO BECOME SEVERE WITH THE MAIN THREAT TO BE DAMAGING
WINDS. HOWEVER...THE DETERMINISTIC MODELS ARE FOCUSING THE BEST
CHANCES FOR CONVECTION TO AFFECT MAINLY THE NORTHERN HALF OF THE
FORECAST AREA THROUGH SUNDAY...WITH THE 20.12Z GFS SUGGESTING MUCH OF
THE CONVECTION TO BE NORTH AND NORTHWEST OF THE FORECAST AREA.
CONFIDENCE IN FORECAST REMAINS LOW FRIDAY NIGHT INTO SUNDAY.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 316 PM CDT THU JUN 20 2013
MAIN FORECAST CONCERNS ARE PRECIPITATION CHANCES THROUGH THE PERIOD.
THE 20.12Z GFS/NAM/GEM ARE IN AGREEMENT IN EJECTING OUT A
COUPLE OF SHORTWAVE TROUGHS INTO THE UPPER MIDWEST THROUGH 00Z
WEDNESDAY...THEN MODELS BEGIN TO DIG UPPER LEVEL TROUGH OVER THE
GREAT LAKES REGION AND DEVELOP NORTHWEST FLOW ALOFT OVER FORECAST
AREA WEDNESDAY INTO THURSDAY. WITH ENOUGH LIFT AND MOISTURE IN
ASSOCIATION WITH SHORTWAVE TROUGHS WILL CONTINUE WITH SMALL CHANCES
OF PRECIPITATION THROUGH MUCH OF THE PERIOD. TEMPERATURES THROUGH
12Z WEDNESDAY WILL BE ABOVE NORMAL...AS THE DETERMINISTIC MODELS
ADVECT WARMER AIR ALOFT INTO FORECAST AREA MONDAY INTO
TUESDAY. THE 20.12Z GFS/ECMWF ARE SHOWING 925MB TEMPERATURES PLUS 24
TO 27 DEGREES CELSIUS BY 00Z WEDNESDAY AND THE 20.00Z GEFS
INDICATE STANDARDIZED ANOMALIES OF 1-1.5 ABOVE NORMAL. THIS WILL
ALLOW TEMPERATURES TO CLIMB INTO THE UPPER 80S TO POSSIBLY
INTO THE MIDDLE 90S ACROSS FORECAST AREA. COOLER AIR WILL FILTER
INTO THE FORECAST BEHIND SURFACE LOW/SHORTWAVE TROUGH WEDNESDAY INTO
THURSDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1138 PM CDT THU JUN 20 2013
COMPLEX OF STORMS OVER NORTHWEST MINNESOTA INTO EASTERN NORTH
DAKOTA HAS YET TO FORM INTO A LINE AND START MOVING MOVING EAST AS
EARLIER DEPICTED BY SEVERAL MODELS. THE 21.02Z HRRR NOW SUGGESTS
THAT THIS COMPLEX OF STORMS WILL NEVER GET HERE BUT RATHER STAY
NORTH OF THE WARM FRONT THAT EXTENDS ACROSS CENTRAL MINNESOTA INTO
NORTHERN WISCONSIN. RATHER...ADDITIONAL DEVELOPMENT IS EXPECTED TO
OCCUR SOUTH OF THE BOUNDARY IN THE LOW LEVEL JET AND MOISTURE
TRANSPORT AXIS OVER SOUTHERN MINNESOTA INTO NORTHERN IOWA. SOME
INDICATIONS THAT THIS IS OCCURRING WITH RECENT DEVELOPMENT OVER
SOUTHERN MINNESOTA. THE HRRR THEN CONTINUES TO EXPAND THIS THROUGH
THE NIGHT AND BRINGS IT INTO THE AREA LATE. HAVE THUS CONTINUED
THE TRENDS OF THE PREVIOUS FORECASTS BUT PUSHED THE TIMING BACK
JUST A LITTLE. COULD STILL SEE SOME GUSTY WINDS AND MVFR
VISIBILITY RESTRICTIONS SO MAINTAINED THOSE TRENDS AS WELL. STILL
EXPECTING THE ACTIVITY TO CLEAR THE AREA BY THE MIDDLE OF FRIDAY
MORNING WITH LITTLE CHANCE OF ANYTHING AFTER THAT FOR THE
REMAINDER OF THE PERIOD WITH THE NEXT ROUND OF STORMS REMAINING
WELL OFF TO THE WEST THROUGH 22.06Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DTJ
LONG TERM....DTJ
AVIATION...04
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
947 PM MDT SAT JUN 22 2013
.UPDATE...
ISSUED AT 938 PM MDT SAT JUN 22 2013
SHOWERS AND TSTMS ARE REALLY BEGINNING TO WIND DOWN AS THE STRONG
SHORTWAVE PASSES ACROSS THE CWA AND THE SUBSIDENCE FOLLOWS. KEPT
SCATTERED SHOWERS IN THE NEBRASKA PANHANDLE THROUGH MIDNIGHT THEN
REMOVED ANY MENTION OF PRECIP. SHOULD BE A QUIET NIGHT AS A WEAK
FRONTAL PASSAGE SWITCHES WINDS TO THE NORTH. THE NAM SUGGESTS LOW
CLOUDS WILL BE POSSIBLE OVER THE PLAINS LATER TONIGHT WHEREAS THE
GFS IS DRIER IN THE LLVLS. WILL KEEP LOW CLOUDS OUT OF THE GRIDS
FOR NOW WITH THE HRRR ONLY SHOWING IFR CIGS ALONG THE SOUTHERN
LARAMIE RANGE EASTWARD INTO LARAMIE COUNTY.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 417 PM MDT SAT JUN 22 2013
THE CLUSTER OF THUNDERSTORMS MOVING THROUGH AREAS EAST OF THE
LARAMIE RANGE WILL CONTINUE TO SHIFT EAST DURING THE COURSE OF THE
EVENING. 0-1KM STORM RELATIVE HELICITY VALUES ARE RANGING FROM
50-100M^2/S^2 IN GOSHEN AND ALBANY COUNTIES. FURTHER EAST OF THIS
LCLS ARE A BIT LOWER WITH VALUES RANGING FROM 500M- 1000M.
THEREFORE...CONTINUED TORNADO THREAT LOOKS TO BE FAIRLY MARGINAL
THIS EVENING...BUT STILL CANNOT RULE SOME BRIEF TOUCHDOWNS AS THE
LINE CONTINUES TO PUSH EAST. MEANWHILE...LARGE HAIL AND DAMAGING
WIND THREAT STILL LOOKS FAVORABLE AT THIS TIME. ALL OF THIS
ACTIVITY CONTINUES TO DEVELOP AHEAD OF THE MAIN SHORTWAVE PIVOTING
THROUGH CENTRAL WYOMING. THIS SHORTWAVE WILL CONTINUE TO SHIFT
EAST THIS EVENING AND BRING DRIER AIR INTO THIS EVENING. WE WILL
BE CLEARING THE TORNADO WATCH IN CONVERSE AND ALBANY COUNTIES
SHORTLY.
TONIGHT AND SUNDAY:
CLEARING SKIES ARE EXPECTED LATE THIS EVENING AND OVERNIGHT AS THE
SUBSIDENCE BUILDS IN WITH THE PASSING SHORTWAVE. IT MAY BE QUITE
COOL IN A FEW LOCATIONS WITH 40S IN WYOMING AND 50S IN THE
NEBRASKA PANHANDLE. LEE SIDE TROF DOES TRY TO SET UP CAMP...BUT
NOT REAL CONFIDENT THAT SHOWERS AND STORMS WILL DEVELOP. FOR
NOW...WE WILL CONSISTENCY SAKE WE WILL KEEP THE CHANCE OF SHOWERS
AND THUNDERSTORMS IN THE PICTURE.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 417 PM MDT SAT JUN 22 2013
NOT MANY CHANGES MADE TO THE LONG TERM DUE TO WIDESPREAD SEVERE
WEATHER THIS AFTERNOON. WE WILL NEED TO WATCH FOR A POTENTIAL
SHORTWAVE MOVING THROUGH THE NORTHERN PARTS OF THE FORECAST AREA
MONDAY NIGHT AND TUESDAY WHICH MAY BRING A CHANCE OF SHOWERS OF
THUNDERSTORMS. OTHERWISE...THE UPPER LEVEL RIDGE WILL CONTINUE TO
BUILD OVER THE REGION LATER IN THE WEEK AND BRING WARMER
TEMPERATURES.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED
AT 530 PM MDT SAT JUN 22 2013
VFR CONDITIONS ARE EXPECTED ACROSS THE WYOMING TAF SITES TONIGHT.
HOWEVER...THERE MAY BE A CHANCE OF ISOLATED AFTERNOON
THUNDERSTORMS MAINLY NEAR THE CYS TAF SITE ON SUNDAY AFTERNOON IN
ASSOCIATION WITH A WEAK UPPER LEVEL WAVE MOVING THROUGH SOUTHEAST
WYOMING AND SOUTHERN NEBRASKA PANHANDLE LATE SUNDAY AFTERNOON.
&&
.FIRE WEATHER...
ISSUED AT 417 PM MDT SAT JUN 22 2013
LOW RELATIVE HUMIDITIES WILL BE IN STORE FOR AREAS MAINLY WEST OF
THE LARAMIE RANGE SUNDAY AFTERNOON. OTHERWISE...THE LEE SIDE TROF
IS EXPECTED TO DEVELOP OVER THE AREA ON MONDAY WITH GUSTY AND DRY
SOUTHWEST FLOW POSSIBLE WEST OF THE LARAMIE RANGE ON MONDAY WHICH
WILL FAVOR INCREASE FIRE RISK.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...FINCH
SHORT TERM...REC
LONG TERM...SLA
AVIATION...REC
FIRE WEATHER...REC
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
220 PM MDT FRI JUN 21 2013
.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 18Z TAFS THROUGH 18Z SATURDAY MORNING)
ISSUED AT 1139 AM MDT FRI JUN 21 2013
LOW CIGS WILL LINGER THROUGH 21Z OVER PORTIONS OF THE NEBRASKA
PANHANDLE WESTWARD INTO EAST CENTRAL WYOMING. OTHERWISE...VFR
CONDITIONS ARE EXPECTED ALONG THE I80 CORRIDOR FROM RAWLINS TO
SIDNEY NEBRASKA UNTIL LATE THIS AFTERNOON. THUNDERSTORMS...SOME
SEVERE...WILL DEVELOP ALONG THE NEBRASKA/WYOMING STATE LINE AROUND
21Z AND MOVE NORTHEAST THROUGH THIS EVENING. ERRATIC GUSTY WINDS UP
TO 50 MPH...HAIL...AND IFR CONDITIONS ARE POSSIBLE WITH THESE
THUNDERSTORMS EAST OF A LINE FROM KIMBALL NEBRASKA TO LUSK
WYOMING...INCLUDING KCDR...KSNY...KBFF...AND KAIA. 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.
&&
$$
SHORT TERM...CLAYCOMB
LONG TERM...TJT
AVIATION...TJT
FIRE WEATHER...CLAYCOMB
AREA FORECAST DISCUSSION
NWS LINCOLN IL
231 AM CDT SUN JUN 23 2013
.DISCUSSION...
ISSUED 230 AM CDT SUN JUN 23 2013
SHORT TERM...TODAY THROUGH TUESDAY...
PROBLEMATIC FORECAST CONTINUES FOR THE NEXT FEW DAYS IN REGARDS TO
CONVECTIVE DEVELOPMENT. EVENTS OF THE LAST COUPLE DAYS HAVE SHOWN
HOW LEFTOVER BOUNDARIES LEAD TO REDEVELOPMENT IN THE HEAT OF THE
DAY...AND ANOTHER SUCH BOUNDARY IS DROPPING SOUTHWARD THROUGH
FAR NORTHERN ILLINOIS...FORMED BY A DECAYING MCS OVER WISCONSIN
AND SOUTHEAST MINNESOTA. SOME WEAK BOUNDARIES ALSO DETECTED OVER
SOUTHEAST ILLINOIS LOOPING WESTWARD INTO AREAS SOUTHWEST OF SAINT
LOUIS. STORMS THAT FORM TODAY SHOULD BE VERY EFFICIENT RAIN MAKERS
AGAIN...AS PRECIPITABLE WATER VALUES WILL BE AROUND 1.7 INCHES AND
700 MB WINDS OF LESS THAN 10 KNOTS INDICATE THE STORMS WILL BE IN
NO HURRY TO MOVE ONCE THEY FORM. LATEST RAP AND HRRR MODELS SHOW
SOME DEVELOPMENT TAKING PLACE AS EARLY AS SUNRISE NEAR THE
SOUTHERN OUTFLOW...AND AFTERNOON DEVELOPMENT SHOULD ACCOMPANY THE
NORTHERN BOUNDARY. HAVE GONE A LITTLE MORE AGGRESSIVE WITH THE
POPS AS A RESULT WITH 30-40 PERCENT MOST AREAS TODAY.
OVERNIGHT PROBLEM THEN SHIFTS TO TRACK OF THE NEXT MCS WHICH
SHOULD FORM OVER IOWA THIS EVENING. NAM AND GFS ARE MORE
PROGRESSIVE WITH SPREADING IT OVER MUCH OF ILLINOIS BY EARLY
MONDAY MORNING...WHILE THE LATEST ECMWF IS SLOWER AND SHUNTS MOST
OF IT OFF TO OUR NORTH. LEANING TOWARD A MORE SOUTHERN SOLUTION AT
THE MOMENT WITH 40-50 PERCENT POPS FROM ABOUT I-55 NORTHWEST...
WITH MAINLY SLIGHT CHANCES ACROSS THE SOUTHEAST. ONCE THIS
PARTICULAR MCS EXITS ON MONDAY...THE STORM TRACK FOR THE NEXT
ROUND SHIFTS A BIT FURTHER NORTH AS SOME UPPER RIDGING BUILDS INTO
THE MID-MISSISSIPPI VALLEY.
TEMPERATURE-WISE...STILL LOOKING LIKE 90 DEGREES OR A BIT HIGHER
IS LIKELY THE NEXT FEW DAYS...PROVIDED THE STORMS DO NOT GET OUT
OF CONTROL. SLOW BUILD OF THE DEW POINTS TOWARD THE MID 70S WILL
RESULT IN HEAT INDEX VALUES A FEW DEGREES HIGHER EACH DAY...WITH
MOST AREAS JUST ABOVE 100 FOR HEAT INDEX BY TUESDAY AFTERNOON.
LONG TERM...WEDNESDAY THROUGH SATURDAY...
SUMMER-TIME PATTERN TO CONTINUE THROUGH MID WEEK. MAIN STORM TRACK
WILL BE ACROSS THE NORTH CENTRAL STATES...WITH SOME POTENTIAL FOR
SHOWERS/STORMS FURTHER SOUTH AS THE OUTFLOWS FROM THE NIGHTLY MCS
SYSTEMS DROP INTO OUR AREA. BEST CHANCE OF RAIN WILL PROBABLY BE
WEDNESDAY NIGHT...AS A SHORTWAVE DROPS INTO THE MIDWEST ALONG WITH
AN ASSOCIATED SURFACE BOUNDARY.
AS THE END OF THE WEEK PROGRESSES...UPPER LEVEL RIDGING WILL BUILD
ACROSS THE ROCKIES...WITH A NORTHWEST FLOW BRINGING COOLER
CONDITIONS TO THE MIDWEST FOR FRIDAY AND ESPECIALLY THE WEEKEND.
THINK MOST OF THE RAIN THREAT WILL BE OUT OF THE AREA BY THURSDAY
EVENING...BUT WEAK TROUGHS ROTATING THROUGH THE MIDWEST MAY
COMPLICATE THIS THINKING.
GEELHART
&&
.AVIATION...
ISSUED 1201 AM CDT SUN JUN 23 2013
SOME SHIFTS IN THE FORECAST AS DEC CMI AND BMI ALL DROPPING TEMPS
CLOSE TO DWPTS AND INCREASING CHANCE FOR AT LEAST MVFR VIS. HRRR
AND 4KM WRF BOTH SHOWING ENOUGH SCT SHOWERS TO START THE TREND FOR
TOMORROW STARTING IN THE 16-18Z TIME FRAME. MAY NEED TO CONVERT TO
THUNDER SHOULD THE TREND CONTINUE. SOUTHERLY FLOW THROUGH THE
OVERNIGHT...WILL BE A BIT OF AN ISSUE FOR FG DEVELOPMENT. GETTING
GUSTY AGAIN TOMORROW AND TAKING ON A BIT OF A SWRLY COMPONENT.
SCATTERING CLOUDS BACK OUT AFTER SUNSET TOMORROW.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WICHITA KS
1146 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 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1142 PM CDT SAT JUN 22 2013
BREEZY SOUTHERLY WINDS WILL BEGIN TO DIMINISH ACROSS CENTRAL
KANSAS ON SUNDAY AS A SURFACE TROUGH AXIS APPROACHES THE AREA.
FURTHER EAST...ANOTHER BREEZY DAY IS ANTICIPATED WITH SPEEDS
AROUND 25 KNOTS GUSTING INTO THE 30-35 KNOT RANGE. THIS TROUGH
AXIS MAY ALSO SERVE AS A FOCUS FOR LATE AFTERNOON AND EVENING
THUNDERSTORM DEVELOPMENT IMPACTING KRSL AND POSSIBLE KSLN DURING
THE EVENING/OVERNIGHT HOURS ON SUNDAY. THERE IS STILL SOME CONCERN
FOR AN ISOLATED SHOWER OR THUNDERSTORM IMPACTING CENTRAL KANSAS
LATE TONIGHT/EARLY TOMORROW MORNING AS AN OUTFLOW BOUNDARY ACROSS
WESTERN KANSAS RACES EASTWARD AFTER 12-14Z.
&&
.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...
NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
220 AM EDT SUN JUN 23 2013
.UPDATE...
ISSUED AT 1250 AM EDT SUN JUN 23 2013
UPDATED THE FORECAST TO REMOVE THE POPS AND FINE TUNE TEMPS THROUGH
THE REST OF THE NIGHT. UPDATES HAVE BEEN SENT TO THE NDFD AND WEB
SERVERS ALONG WITH A FRESHENED ZFP AND HWO.
UPDATE ISSUED AT 1027 PM EDT SAT JUN 22 2013
UPDATED THE FORECAST TO BETTER REFLECT CURRENT CONDITIONS AND MODEL
TRENDS. ISOLATED THE SCATTERED THUNDERSTORMS HAVE BEEN PERCOLATING
WEST OF A LINE FROM MOUNT STERLING TO HARLAN. A FEW OF THESE
PULSING THUNDERSTORMS HAVE BECOME STRONG...HOWEVER THEY HAVE STAYED
BELOW SEVERE CRITERIA. THE HRRR AND EXTRAPOLATION INDICATE ALL THE
STORMS SHOULD BE MOVING OUT OF THE AREA BY MIDNIGHT. SOME AREAS
DIRECTLY UNDERNEATH THE STORMS HAVE RECEIVED AND MUCH AS 1.5 INCHES
OF RAIN...HOWEVER THE STORMS HAVE BEEN MOSTLY MISSING THE RAIN GAGES OUT
THERE. WILL HAVE A BETTER IDEA WHEN ALL THE CO-OPS REPORT IN THE
MORNING. THE REST OF FORECAST IS ON TRACK.
UPDATE ISSUED AT 812 PM EDT SAT JUN 22 2013
UPDATED THE FORECAST TO BETTER REFLECT CURRENT CONDITIONS AND MODEL
TRENDS. THUNDERSTORMS HAVE BEEN HAVING A HARD TIME GETTING STRONG
THIS AFTERNOON AND EVENING. PART OF THE PROBLEM IS SOME WARMING THE
MID LEVELS WHICH IS HELPING TO CAP THEM OFF. THE STRONGEST STORMS
THIS EVENING WERE OVER KNOX AND WAYNE COUNTIES. THEY NEVER QUITE GOT
TO THE POINT WHERE A SPECIAL WEATHER STATEMENT WAS NEEDED AND THEY
WERE NOT CLOSE TO THE CRITERIA WE USED TO ISSUE SEVERE THUNDERSTORM
WARNINGS. EXPECT STORMS TO DIE OFF BY 10 PM. SOME PATCHY VALLEY FOG
IS EXPECTED TONIGHT...ESPECIALLY IN AREAS THAT RECEIVED RAIN THIS
EVENING. THE REST OF THE FORECAST IS ON TRACK.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 320 PM EDT SAT JUN 22 2013
CONVECTION ACROSS THE CWA HAS BEEN LIMITED SO FAR THIS AFTERNOON.
APPEARS MID LEVEL CAPPING IS JUST A BIT TOO STRONG TO OVERCOME AND IS
RESPONSIBLE FOR DAMPENING ACTIVITY THUS FAR. AS A RESULT PULLED BACK
SLIGHTLY ON POPS FOR THE REMAINDER OF THE AFTERNOON. ALOFT A WEAK
UPPER LOW WILL MOVE SLOWLY NORTHWARD ACROSS THE REGION DURING THE
NEXT 24 HOURS. CAPPING SHOULD WEAKEN A BIT ON SUNDAY AS THE UPPER LOW
MOVES OVERHEAD. SO CONTINUED TO ADVERTISE SLIGHTLY BETTER COVERAGE OR
SCATTERED ACTIVITY SUNDAY AFTERNOON FOR AT LEAST A GOOD PORTION OF
THE CWA. NO SIGNIFICANT CHANGES TO TEMPS. DID NUDGE THEM TOWARDS A
BLEND OF LATEST MODEL GUIDANCE. WITH A PERSISTENT PATTERN IN PLACE
THERE SHOULD NOT BE TOO MUCH VARIATION IN DAY TO DAY SENSIBLE
WEATHER...A TYPICAL SUMMER LIKE PATTERN.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 320 PM EDT SAT JUN 22 2013
DURING THE FIRST HALF OF THE TIME FRAME THE MAIN WESTERLIES SHOULD
BE TO OUR NORTH...WITH AN UPPER LEVEL RIDGE AXIS ORIENTED WEST/EAST
OVER THE SOUTHERN CONUS. WITHOUT A CRUSHING RIDGE OVER US AND WITH A
WARM AND MOIST AIR MASS STILL IN PLACE...WILL EXPECT SHOWERS AND
THUNDERSTORMS TO POP UP AT TIMES. IT SHOULD BE LARGELY A DIURNAL
TREND LINKED WITH PEAK HEATING. HOWEVER...DUE TO LACK OF FEATURES TO
FOCUS CONVECTION...POPS WILL BE LOW...GENERALLY 20-30 PERCENT EACH
AFTERNOON...AND DROPPING OFF AT NIGHT.
LATE IN THE WEEK...THE UPPER RIDGE IS EXPECTED TO BUILD MUCH
STRONGER OVER THE SOUTHWEST CONUS...ALLOWING TROUGHING TO DEVELOP IN
THE EAST. SHORTWAVE TROUGHS DROPPING INTO THE SYNOPTIC SCALE TROUGH
WILL THEN PROVIDE A FOCUS FOR CONVECTION. ONE SUCH SHORTWAVE
TROUGH...ALBEIT FAIRLY WEAK...IS SHOWN BY BOTH THE ECMWF AND GFS
MODELS ARRIVING ON THURSDAY. WILL USE LOW CHANCE POPS AREA WIDE WITH
THIS. MODELS THEN SHOW THE LARGE SCALE UPPER TROUGH CONTINUING TO
DEEPEN...AND BRINGING A SURFACE COLD FRONT INTO THE AREA FROM THE
NORTHWEST ON FRIDAY. WILL RAISE POPS TO 50 PERCENT WITH THIS
FEATURE. IF THE CURRENT FORECAST SCENARIO HOLDS IN FUTURE RUNS...
POPS WILL LIKELY GO HIGHER. BOTH THE ECMWF AND GFS GENERATE PRECIP
BEHIND THE COLD FRONT UNDER THE UPPER TROUGH ON SATURDAY. THE GFS
DOES SHOW A SURFACE TROUGH MOVING THROUGH...AND GFS MEX MOS HAS 50
PERCENT POPS ON SATURDAY. HOWEVER...FORECAST SOUNDINGS DO NOT LOOK
ALL THAT SUPPORTIVE OF PRECIP...AND THE ECMWF IS LIGHTER WITH ITS
QPF FIELD THAN THE GFS. WILL UNDERCUT THE MOS AND GO WITH 30 PERCENT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 220 AM EDT SUN JUN 23 2013
ALTHOUGH VFR CONDITIONS CAN BE EXPECTED THROUGH THE BULK OF THE
FORECAST PERIOD...THERE WILL LIKELY BE TIMES OF MVFR OR LOWER VIS AND
CIGS EARLY THIS MORNING FROM FOG...ESPECIALLY AT LOZ WHERE A BIT OF
RAIN AGAIN FELL. OTHERWISE...SCATTERED THUNDERSTORMS FROM MID DAY
INTO THE EARLY EVENING ON SUNDAY WILL ALSO THREATEN TO REDUCE VIS
AND CIGS TO MVFR...BUT MOST SITES WILL PROBABLY STAY STORM AND
PROBLEM FREE. WINDS WILL BE LIGHT AND VARIABLE THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...RAY
LONG TERM...HAL
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1250 AM EDT SUN JUN 23 2013
.UPDATE...
ISSUED AT 1250 AM EDT SUN JUN 23 2013
UPDATED THE FORECAST TO REMOVE THE POPS AND FINE TUNE TEMPS THROUGH
THE REST OF THE NIGHT. UPDATES HAVE BEEN SENT TO THE NDFD AND WEB
SERVERS ALONG WITH A FRESHENED ZFP AND HWO.
UPDATE ISSUED AT 1027 PM EDT SAT JUN 22 2013
UPDATED THE FORECAST TO BETTER REFLECT CURRENT CONDITIONS AND MODEL
TRENDS. ISOLATED THE SCATTERED THUNDERSTORMS HAVE BEEN PERCOLATING
WEST OF A LINE FROM MOUNT STERLING TO HARLAN. A FEW OF THESE
PULSING THUNDERSTORMS HAVE BECOME STRONG...HOWEVER THEY HAVE STAYED
BELOW SEVERE CRITERIA. THE HRRR AND EXTRAPOLATION INDICATE ALL THE
STORMS SHOULD BE MOVING OUT OF THE AREA BY MIDNIGHT. SOME AREAS
DIRECTLY UNDERNEATH THE STORMS HAVE RECEIVED AND MUCH AS 1.5 INCHES
OF RAIN...HOWEVER THE STORMS HAVE BEEN MOSTLY MISSING THE RAIN GAGES OUT
THERE. WILL HAVE A BETTER IDEA WHEN ALL THE CO-OPS REPORT IN THE
MORNING. THE REST OF FORECAST IS ON TRACK.
UPDATE ISSUED AT 812 PM EDT SAT JUN 22 2013
UPDATED THE FORECAST TO BETTER REFLECT CURRENT CONDITIONS AND MODEL
TRENDS. THUNDERSTORMS HAVE BEEN HAVING A HARD TIME GETTING STRONG
THIS AFTERNOON AND EVENING. PART OF THE PROBLEM IS SOME WARMING THE
MID LEVELS WHICH IS HELPING TO CAP THEM OFF. THE STRONGEST STORMS
THIS EVENING WERE OVER KNOX AND WAYNE COUNTIES. THEY NEVER QUITE GOT
TO THE POINT WHERE A SPECIAL WEATHER STATEMENT WAS NEEDED AND THEY
WERE NOT CLOSE TO THE CRITERIA WE USED TO ISSUE SEVERE THUNDERSTORM
WARNINGS. EXPECT STORMS TO DIE OFF BY 10 PM. SOME PATCHY VALLEY FOG
IS EXPECTED TONIGHT...ESPECIALLY IN AREAS THAT RECEIVED RAIN THIS
EVENING. THE REST OF THE FORECAST IS ON TRACK.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 320 PM EDT SAT JUN 22 2013
CONVECTION ACROSS THE CWA HAS BEEN LIMITED SO FAR THIS AFTERNOON.
APPEARS MID LEVEL CAPPING IS JUST A BIT TOO STRONG TO OVERCOME AND IS
RESPONSIBLE FOR DAMPENING ACTIVITY THUS FAR. AS A RESULT PULLED BACK
SLIGHTLY ON POPS FOR THE REMAINDER OF THE AFTERNOON. ALOFT A WEAK
UPPER LOW WILL MOVE SLOWLY NORTHWARD ACROSS THE REGION DURING THE
NEXT 24 HOURS. CAPPING SHOULD WEAKEN A BIT ON SUNDAY AS THE UPPER LOW
MOVES OVERHEAD. SO CONTINUED TO ADVERTISE SLIGHTLY BETTER COVERAGE OR
SCATTERED ACTIVITY SUNDAY AFTERNOON FOR AT LEAST A GOOD PORTION OF
THE CWA. NO SIGNIFICANT CHANGES TO TEMPS. DID NUDGE THEM TOWARDS A
BLEND OF LATEST MODEL GUIDANCE. WITH A PERSISTENT PATTERN IN PLACE
THERE SHOULD NOT BE TOO MUCH VARIATION IN DAY TO DAY SENSIBLE
WEATHER...A TYPICAL SUMMER LIKE PATTERN.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 320 PM EDT SAT JUN 22 2013
DURING THE FIRST HALF OF THE TIME FRAME THE MAIN WESTERLIES SHOULD
BE TO OUR NORTH...WITH AN UPPER LEVEL RIDGE AXIS ORIENTED WEST/EAST
OVER THE SOUTHERN CONUS. WITHOUT A CRUSHING RIDGE OVER US AND WITH A
WARM AND MOIST AIR MASS STILL IN PLACE...WILL EXPECT SHOWERS AND
THUNDERSTORMS TO POP UP AT TIMES. IT SHOULD BE LARGELY A DIURNAL
TREND LINKED WITH PEAK HEATING. HOWEVER...DUE TO LACK OF FEATURES TO
FOCUS CONVECTION...POPS WILL BE LOW...GENERALLY 20-30 PERCENT EACH
AFTERNOON...AND DROPPING OFF AT NIGHT.
LATE IN THE WEEK...THE UPPER RIDGE IS EXPECTED TO BUILD MUCH
STRONGER OVER THE SOUTHWEST CONUS...ALLOWING TROUGHING TO DEVELOP IN
THE EAST. SHORTWAVE TROUGHS DROPPING INTO THE SYNOPTIC SCALE TROUGH
WILL THEN PROVIDE A FOCUS FOR CONVECTION. ONE SUCH SHORTWAVE
TROUGH...ALBEIT FAIRLY WEAK...IS SHOWN BY BOTH THE ECMWF AND GFS
MODELS ARRIVING ON THURSDAY. WILL USE LOW CHANCE POPS AREA WIDE WITH
THIS. MODELS THEN SHOW THE LARGE SCALE UPPER TROUGH CONTINUING TO
DEEPEN...AND BRINGING A SURFACE COLD FRONT INTO THE AREA FROM THE
NORTHWEST ON FRIDAY. WILL RAISE POPS TO 50 PERCENT WITH THIS
FEATURE. IF THE CURRENT FORECAST SCENARIO HOLDS IN FUTURE RUNS...
POPS WILL LIKELY GO HIGHER. BOTH THE ECMWF AND GFS GENERATE PRECIP
BEHIND THE COLD FRONT UNDER THE UPPER TROUGH ON SATURDAY. THE GFS
DOES SHOW A SURFACE TROUGH MOVING THROUGH...AND GFS MEX MOS HAS 50
PERCENT POPS ON SATURDAY. HOWEVER...FORECAST SOUNDINGS DO NOT LOOK
ALL THAT SUPPORTIVE OF PRECIP...AND THE ECMWF IS LIGHTER WITH ITS
QPF FIELD THAN THE GFS. WILL UNDERCUT THE MOS AND GO WITH 30 PERCENT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 812 PM EDT SAT JUN 22 2013
THUNDERSTORMS SHOULD DYE DOWN BY 2Z. EXPECT SOME PATCHY DENSE VALLEY
FOG IN THE VALLEYS AGAIN TONIGHT...ESPECIALLY IN THE LOCATIONS THAT
SAY RAINFALL TODAY. LOOKING FOR VFR CONDITIONS THROUGH THE BULK OF
THE FORECAST. WILL ALL THINGS BEING PRETTY MUCH EQUAL DECIDED TO LEAN
HEAVILY ON PERSISTENCE FOR TIMING OF LIGHT FOG AT EACH TERMINAL.
LOOKING FOR DIURNAL ISOLD TO SCATTERED SHOWERS AND THUNDERSTORMS TO
BEGIN FIRING ACROSS THE AREA AFTER 18Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...RAY
LONG TERM...HAL
AVIATION...JJ
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
119 AM EDT SUN JUN 23 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 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 118 AM EDT SUN JUN 23 2013
WITH ABUNDANT LOW-LEVEL MOISTURE LINGERING OVER THE REGION TO THE N
OF A WARM FRONT...IFR/LIFR CONDITIONS ARE EXPECTED THRU THE NIGHT AT
KCMX/KSAW AS BOTH OF THESE TERMINALS WILL ALSO HAVE A LIGHT UPSLOPE
WIND. UNDER A DOWNSLOPE SE/S WIND AT KIWD...CONDITIONS THERE SHOULD
NOT FALL BLO MVFR. DAYTIME HEATING COMBINED WITH WARM FRONT LIFTING
N OF THE AREA TODAY WILL RESULT IN ALL TERMINALS IMPROVING TO VFR.
AS FOR PCPN...SHRA/TSRA POTENTIAL REMAINS UNCERTAIN. THERE APPEARS
TO BE INCREASING POTENTIAL FOR SHRA/TSRA IN THE MORNING HRS AS WARM
FRONT LIFTS N INTO THE AREA. HAVE INCLUDED VCSH TO TREND TOWARD PCPN
POSSIBILITY. NOT THE IDEAL TIME OF DAY FOR TSRA...BUT TSRA NOT OUT
OF THE QUESTION. MAY SEE ANOTHER ROUND OF SHRA/TSRA LATE THIS
AFTN/EVENING AS INSTABILITY BUILDS IN WARM/HUMID AIR MASS.
HOWEVER...CONFIDENCE IN COVERAGE/LOCATION OF ANY CONVECTION THAT
MIGHT DEVELOP IS VERY LOW. FOR NOW...ONLY INCLUDED VCTS LATE AFTN AT
KSAW AS SOME OF THE HIGHER RESOLUTION MODEL GUIDANCE HINTS AT A
BETTER POTENTIAL OF CONVECTION ACROSS CNTRL UPPER MI.
&&
.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/ THIS MORNING FOR
LSZ162-240>250-263>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...ROLFSON
MARINE...JLA
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
133 AM CDT SUN JUN 23 2013
.UPDATE...
ISSUED AT 645 PM CDT SAT JUN 22 2013
RECENT TRENDS WITH THE HRRR ALONG WITH HEAVY RAIN PROBABILITIES
FROM THE SREF AND THE OVERNIGHT QPF PLACEMENT FROM THE ECMWF HAS
PROMPTED A FLASH FLOOD WATCH THROUGH EARLY SUNDAY MORNING FOR A
GOOD PORTION OF CENTRAL AND SOUTHERN MN. RAINFALL AMOUNTS FROM THE
HRRR ARE IN THE 2 TO 3 INCH RANGE FROM MONTEVIDEO AND APPLETON ON
EAST THROUGH THE TWIN CITIES. THIS LINES UP WELL WITH THE SREF
PROBABILITIES OF 1 AND 2 INCH RAINS OVERNIGHT AND THE 12 HOUR QPF
FROM THE ECMWF. THIS IS ALSO AT THE NOSE OF THE RAP 925-850MB
MOISTURE TRANSPORT BETWEEN 06Z AND 12Z.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 334 PM CDT SAT JUN 22 2013
BIG THING TO START OFF THE SHORT TERM IS THE PRESENCE OF A
STRENGTHENING WARM FRONT ACROSS SRN MN...WHICH STRETCHES FROM
MARSHALL OVER TO FARIBAULT AND LA CROSSE AT 330 PM. SOUTH OF THE
BOUNDARY...SKIES HAVE CLEARED...WITH TEMPS RISING TO AROUND 90 TO
GO WITH MID/UPPER 60 DEWPOINTS. THIS BOUNDARY IS BEING REINFORCED
BY A COOL AND SHALLOW RIDGE OF HIGH PRESSURE THAT HAS COME DOWN
FROM THE NORTHEAST OFF OF LAKE SUPERIOR. FARTHER WEST...THERE IS
A DIFFUSE PRESSURE TROUGH/FRONT ORIENTED N/S ACROSS THE CENTRAL
DAKOTAS.
TONIGHT...THE WARM FRONT WILL TRY TO PUSH NORTH TO ABOUT THE I-94
CORRIDOR...BUT WILL CONTINUALLY BE STRUGGLING AGAINST LAKE
SUPERIOR HIGH. BY SUNDAY MORNING...THE TROUGH BACK OVER THE
DAKOTAS WILL MOVE INTO MN AND WILL BE BISECTING MN FROM THE SW
CORNER UP TOWARD THE INL AREA BY SUNDAY AFTERNOON.
FOR TONIGHT...LOTS OF UNCERTAINTY WITH HOW CONVECTION WILL EVOLVE.
ATMOSPHERE OVER MN/NRN WI REMAINS OVERTURNED AND WORKED OVER
FROM LAST NIGHTS CONVECTION...AS EVIDENCED BY MID LEVEL LAPSE
RATES ON THE SPC MESO ANALYSIS OF 5 TO 7 DEG C PER KM....THOUGH
THEY HAVE STARTED TO SHOWS SIGNS OF RECOVERING IN THE LAST COUPLE
OF HOURS. THESE WEAK LAPSE RATES WILL LIKELY KEEP THINGS FAIRLY
BENIGN ACROSS THE MPX AREA UNTIL CLOSER TO 00Z. AS 00Z
APPROACHES...A 30-40KT LLJ WILL BEGIN COMING UP OUT OF IA AND
IMPINGING ON THE WARM FRONT ACROSS MN...WHICH SHOULD REALLY START
TO RAMP UP PRECIP CHANCES. MAIN QUESTION THEN FOR TONIGHT BECOMES
HOW FAR NORTH DOES THE WARM FRONT AND NOSE OF THE LLJ GO. ONCE
AGAIN...EXPECT THE NOSE OF THE LLJ TO BE VERY ACTIVE...WITH
WIDESPREAD TSRA THAT WILL HAVE THE POTENTIAL TO TRAIN...WITH
ANOTHER ROUND OF HEAVY RAIN AND FLASH FLOODING BEING POSSIBLE
TONIGHT. IN ADDITION TO THE HEAVY RAIN...SHEAR WILL BE SUFFICIENT
ENOUGH TO WARRANT A RISK OF SEVERE WEATHER THROUGH THE
NIGHT...WITH THE MAIN TREAT BEING WET MICRO/DOWN BURSTS ONCE
AGAIN. GOING WITH A BLEND OF THE ECMWF/GFS/NAM...THE PART OF THE
AREA THAT WOULD BE MOST AT RISK FOR SEEING THUNDERSTORMS WOULD
ESSENTIALLY BE THE HEART OF THE MPX CWA FROM SW MN...UP THROUGH
THE TWIN CITIES AND OVER INTO WRN WI.
UNFORTUNATELY...HI-RES MODELS ARE OF NO USE TONIGHT...AS EACH WRF
MEMBER HAS ITS OWN UNIQUE IDEA OF HOW THINGS WILL EVOLVE. AND
THE HRRR HAS SHOWN CONSIDERABLE VARIABILITY FROM RUN TO RUN. GIVEN
ALL OF THE UNCERTAINTY...CAN NOT PIN DOWN EXACTLY WHERE THE
GREATEST FLASH FLOOD EXISTS THROUGH TONIGHT...SO HAVE OPTED NOT TO
ISSUE A FLASH FLOOD WATCH. GREATEST THREAT OF COURSE WOULD BE
ALONG/NORTH OF THE WARM FRONT...WHEREVER IT DECIDES TO SETUP SHOP
TONIGHT.
FOR SUNDAY...THE DAKOTAS BOUNDARY WILL BE DRIFTING INTO MN...WITH
DRIER AIR COMING IN BEHIND IT. THIS MAY ACTUALLY ALLOW FOR A DRY
DAY IN WRN MN...BUT ON THE OTHER SIDE OF THE CWA...THE LLJ WILL
BE INCREASING BY THE AFTERNOON...WITH THUNDERSTORMS EXPECTED TO
AGAIN EXPAND IN COVERAGE FROM SOUTH CENTRAL MN INTO WRN WI.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 334 PM CDT SAT JUN 22 2013
THUNDERSTORM ACTIVITY WILL LIKELY BE ONGOING AT THE START OF THE
LONG TERM PERIOD SUNDAY EVENING ACROSS WRN WI. WEST OF THE COLD
FRONT...DRIER AIR WILL FINALLY BRING CLEARING CONDITIONS AND A
RESPITE FROM REPEATED ROUNDS OF CONVECTION SUNDAY NIGHT AND
MONDAY.
RIDGING WILL BUILD OVER THE PLAINS MONDAY. 925 MB TEMPS MONDAY
WILL RISE TO BETWEEN +23 AND +25C...SO THINKING HIGHS IN THE UPPER
80S ARE LIKELY AND SEVERAL LOCATIONS OVER SWRN MN COULD REACH
THE LOWER 90S.
THE NOSE OF MID LEVEL RIDGING WILL BEGIN TO REACH SRN MN TUESDAY.
MODELS CONTINUE TO ADVERTISE ANOTHER DISTURBANCE SLIDING AROUND...
AND TO THE NORTH OF THIS RIDGING MONDAY NIGHT AND TUESDAY.
MAINTAINED MEDIUM POPS THROUGHOUT THIS TIME. FOLLOWING THE PASSAGE
OF THE ANY MORNING MCS/S...TUESDAY MAY TURN HOT AND HUMID PRIOR TO
COLD FRONTAL PASSAGE TUESDAY EVENING. NAM WOULD FAVOR HIGHS IN THE
LOW/MID 90S WITH PRONOUNCED THERMAL RIDGING. GFS/ECMWF ARE
SLIGHTLY COOLER ACROSS THE ERN CWA WITH MCS CLOUDINESS PERSISTING
INTO THE AFTERNOON HOURS.
A MUCH DRIER PERIOD WILL TAKE HOLD IN THE LATTER HALF OF THE LONG
TERM WITH RIDGING RETROGRADING BACK INTO THE WESTERN STATES AND A
ZONAL TO NORTHWEST FLOW RETURNING TO THE MIDWEST/GREAT LAKES.
THIS WILL BRING COOLER THAN NORMAL TEMPERATURES TO MUCH OF THE
EASTERN CONUS HEADING INTO THE HOLIDAY WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1242 AM CDT SUN JUN 23 2013
NOCTURNAL CONVECTION AGAIN FIRING OVER SRN MN...N OF A LINGERING
STNRY FNT OVER NR IA. THIS FNT WILL TRANSITION TO A WMFNT AND
SLOWLY LIFT N OVERNIGHT AS ADDITIONAL STORMS TRAVERSE THE FNT FROM
W TO E. KRWF THE FIRST TO BE AFFECTED...THEN ACTIVITY WILL
STEADILY SPREAD E. CONDS WILL LIKELY DEGRADE TO MVFR AND POSSIBLY
IFR IN THE TSTM ACTIVITY. THAT BEING SAID...HAVE ALSO SEEN REPORTS
OF A FEW POCKETS OF IFR CIGS...BUT THESE ARE NOT EXPECTED TO LAST
LONG...ESP IF RAIN WASHES IT OUT. CONDS TO GENERALLY IMPROVE TO
VFR BY LATE MRNG AS MIXING OCCURS WITH INCRG S WINDS. VFR WILL
THEN PERSIST THRU MOST OF THE DAY FOR WRN-CENTRAL MN WHILE WRN MN
INTO WRN WI SEE OCNL MVFR CONDS WITH LINGERING SHWRS.
KMSP...MAIN CONCERN REMAINS THE TIMING OF TSTMS. BEST TIMING PUTS
TSTMS INTO THE MSP AREA 07Z-10Z BUT COULD LAST SLIGHTLY LONGER.
MVFR-IFR CIGS WILL LINGER IN THE WAKE OF THESE STORMS. CONDS
IMPROVE GRADUALLY THRU THE DAY WHILE SHWRS/TSTMS DEVELOP E OF THE
MSP TERMINAL. AFTER RELATIVELY LIGHT E WINDS THIS MRNG...SE WINDS
INCRS TO ARND 15 KT THRU THIS AFTN WITH OCNL GUSTS TO ARND 25MPH.
/OUTLOOK FOR KMSP/
MON...VFR. WIND SE 5-10 KTS.
MON NIGHT...CHC TSRA. VFR OUTSIDE OF TSRA. WINDS SE 5-10 KTS.
TUE...CHC TSRA. VFR OUTSIDE OF TSRA. WINDS SSE 10-15 KTS.
WED...CHC TSRA. VFR OUTSIDE OF TSRA. WINDS S SHIFT TO NW 10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...FLASH FLOOD WATCH UNTIL 10 AM CDT THIS MORNING FOR MNZ041-042-
047>049-051-054>062-064>069-073>076-082-083-091.
WI...NONE.
&&
$$
UPDATE...RAH
SHORT TERM...MPG
LONG TERM...BORGHOFF
AVIATION...JPC
AREA FORECAST DISCUSSION
NWS BILLINGS MT
331 AM MDT SUN JUN 23 2013
.SHORT TERM...VALID FOR TDY AND MON...
A WARMING TREND IS IN STORE TODAY AND MON IN THE WAKE OF THE SHORT
WAVE TROUGH WHICH BROUGHT MOISTURE SAT. OUR ATTENTION WILL TURN TO
A CONDITIONAL RISK OF SEVERE STORMS IN SOUTHEASTERN MT BY MON AS A
PLUME OF HIGHER BOUNDARY LAYER MOISTURE TRIES TO MAKE A RUN TOWARD
AT LEAST BAKER JUST AS 500-HPA FLOW BECOMES SOUTHWEST ONCE MORE.
TODAY...A DRYING AND WELL-MIXED AIR MASS WILL YIELD A WARM DAY. WE
HAVE HIGHS A BIT ABOVE THE 00 UTC MULTI-MODEL CONSENSUS OVER PARTS
OF THE AREA IN RESPECT TO EXPECTED MIXING...WHICH SHOULD EXTEND TO
600 HPA IN SOUTH CENTRAL MT AND 700 HPA IN SOUTHEASTERN MT. ONLY A
LOW POP WAS RETAINED IN BAKER THIS MORNING. WE ALSO WENT WITHOUT A
MENTION OF FOG...AS VISIBILITIES OVER SOUTHEASTERN MT HAVE COME UP
SINCE 06 UTC AS WINDS BECAME WEST-SOUTHWEST. HRRR OUTPUT ALSO SAYS
MOST OF THE FOG WILL STAY NORTH AND EAST OF THE AREA THIS MORNING.
TONIGHT...A QUIET PERIOD IS IN STORE FOR MOST OF THE AREA...BUT WE
WILL NEED TO CONSIDER THE POTENTIAL FOR ELEVATED CONVECTION ACROSS
SOUTHEASTERN MT WITH LATER FORECASTS. SERIOUS THOUGHT WAS GIVEN TO
ADDING SOME LOW POPS FOR STORMS AFTER 09 UTC TO AT LEAST BAKER AND
EKALAKA AS A 30 KT LOW-LEVEL JET DEVELOPS. THE 00 UTC GUIDANCE ALL
SHOWS A GRADIENT IN NEGATIVE SHOWALTER INDICES NORMAL TO THAT LOW-
LEVEL JET TOO...WHICH CAN OFTEN BE A GOOD FORECAST SIGNAL FOR SOME
NOCTURNAL STORMS. HOWEVER...HEIGHTS ALOFT WILL BE RISING TOO...AND
THE SUBSIDENCE ASSOCIATED WITH THAT PROCESS CAN DETER DEVELOPMENT.
THUS...WE LEFT A DRY FORECAST IN TACT TONIGHT. NOTE THOUGH THAT WE
ALREADY HAD LOW POPS IN BAKER AND EKALAKA FROM 12 TO 18 UTC ON MON
AND THUS THOSE WERE LEFT IN PLAY.
MON...A MID-LEVEL THERMAL RIDGE WITH 700-HPA TEMPERATURES FROM +11
TO +13 C WILL CROSS THE AREA...LEADING TO HIGHS WELL INTO THE 80S.
MIXING MAY BE SUFFICIENT FOR A CRACK AT 90 F...ESPECIALLY IN SOUTH
CENTRAL MT. GUIDANCE AGREES THAT A LEE TROUGH AND SURFACE LOW WILL
FORM OVER THE AREA...AND SOUTH-SOUTHEAST FLOW SHOULD HAVE A CHANCE
OF PULLING HIGHER DEWPOINTS INTO SOUTHEASTERN MT. MOST MODELS SHOW
SURFACE DEWPOINTS OF 55 TO 60 F AROUND BAKER AND EKALAKA BENEATH A
PLUME OF STEEP MID-LEVEL LAPSE RATES IN EXCESS OF 8 C/KM. ONLY ONE
MEMBER OF THE 21 UTC SREF HAS LESS THAN 1800 J/KG OF MLCAPE ACROSS
THAT AREA BY PEAK HEATING...AND MOST HAVE VALUES OF 2500 J/KG JUST
LIKE THE 00 UTC NAM AND ECMWF SUPPORT. SURFACE HEATING WILL LIKELY
BE ENOUGH TO REMOVE MLCIN...BUT FORCING IS IN QUESTION SINCE THERE
MAY NOT BE MUCH LOW-LEVEL MASS CONVERGENCE IN PLACE. THE CHANCE OF
SEVERE STORMS DRIVEN BY EXPECTED MLCAPE AND VEERING /THOUGH RATHER
MODEST/ WIND PROFILES IS THUS HIGHLY CONDITIONAL ON STORMS GETTING
GOING IN THE FIRST PLACE. MEANWHILE...WE WILL ALSO HAVE CHANCES OF
SOME WEAKER AND HIGH-BASED STORMS ELSEWHERE...ESPECIALLY CLOSER TO
LIVINGSTON WHERE HEIGHTS ALOFT WILL FALL A BIT BY 00 UTC. SCHULTZ
.LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT...
OVERALL THEME OF THE EXTENDED REMAINS IN TACT WITH A RIDGE
PROGGED TO BUILD TO END THE WEEK INTO NEXT WEEKEND. THE TIMING OF
MID LEVEL HEIGHT INCREASES KEEPS BEING DELAYED LITTLE BY A LITTLE.
A SHORTWAVE TROUGH WILL MOVE THROUGH THE AREA EARLY IN THE DAY.
TIMING OF THE WAVE MAY LIMIT CONVECTION CHANCES BUT WILL KEEP
SCATTERED POPS IN AS STILL A FEW DAYS OUT TO GET THE TIMING OF
THIS WAVE DOWN. THE SHORTWAVE ZIPS EAST AND VEERS THE FLOW TO THE
WEST FOR ZONAL FLOW WEDNESDAY. THIS WILL SET UP A PERIOD OF DRY
WEATHER AS THE UPPER RIDGE TO THE SOUTH STARTS TO BUILD IN EARNEST
WEDNESDAY NIGHT.
WILL HAVE TO WATCH RIDGE RIDING SHORTWAVES FROM FRIDAY ONWARD AS
THE TAP TO PACIFIC MOISTURE MAY BE ENOUGH TO TRIGGER CONVECTION.
LOW LEVEL FLOW LOOKS TO BE EASTERLY DURING THIS PERIOD WHICH WILL
KEEP DEWPOINTS UP. LIMITING FACTOR FOR CONVECTION WILL BE THE
STRENGTH OF THE RIDGE ITSELF. WILL KEEP POPS OUT FRIDAY. DID ADD
THEM SATURDAY AS BOTH THE GFS AND ECMWF WERE FAIRLY AGGRESSIVE IN
SLIDING A CHUNK OF ENERGY WITH MID LEVEL MOISTURE INTO THE AREA.
THE MAIN BUILDING OF THE RIDGE HAS HELD OFF UNTIL EARLY NEXT WEEK
AND THE MODELS WERE HAVING DIFFICULTY WITH CONSISTENCY ON THIS.
THE CONSENSUS DOES SEEM TO BE TO DELAY THE HIGHER HEIGHTS AND TO
SHIFT THE AXIS INTO THE GREAT BASIN. THIS POSITION WOULD KEEP THE
POSSIBILITY OF BACK DOOR COOL FRONTS IN PLAY AND WOULD SUPPRESS
MONSOONAL TYPE OF MOISTURE FROM WRAPPING INTO THE STATE. TWH
&&
.AVIATION...
ISOLATED MORNING SHOWERS AND THUNDERSTORMS WILL BE CONFINED TO
LOCATIONS NORTH AND EAST OF A KMLS TO KBHK LINE. THERE IS A
POSSIBILITY OF MVFR CONDITIONS IN A HEAVIER SHOWER BUT VFR IS
EXPECTED TO BE PREDOMINATE. THE CHANCE OF PRECIPITATION WILL EXIT
THIS AFTERNOON. THE REST OF THE AREA WILL HAVE A MOSTLY SUNNY SKY
WITH LIGHT WIND. TWH
&&
.PRELIMINARY POINT TEMP/POPS...
TDY MON TUE WED THU FRI SAT
-------------------------------------------------------
BIL 078 053/088 062/086 058/087 059/088 059/089 059/090
1/U 11/B 23/T 21/B 10/U 00/U 02/T
LVM 078 044/085 054/081 053/083 052/084 053/085 053/086
1/B 13/T 34/T 21/B 11/U 11/U 12/T
HDN 080 051/089 059/088 057/089 059/090 059/091 059/093
1/U 11/B 23/T 21/B 11/U 10/U 01/U
MLS 078 056/089 062/088 060/088 059/087 060/087 060/089
1/B 12/T 23/T 21/B 10/U 01/U 11/U
4BQ 078 052/089 059/089 058/090 059/090 059/089 059/090
1/U 12/T 22/T 21/U 11/U 11/U 11/U
BHK 075 053/086 059/086 058/085 059/084 058/084 061/085
2/W 13/T 32/T 21/U 11/U 10/U 01/U
SHR 078 049/086 055/086 053/087 054/087 053/088 053/089
1/U 11/B 22/T 21/B 11/U 11/U 11/U
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1221 AM CDT SUN JUN 23 2013
.AVIATION...
06Z TAFS FOR KOFK...KOMA AND KLNK.
CONVECTION MOVING THROUGH CENTRAL NEBRASKA WAS SENDING AN OUTFLOW
BOUNDARY TOWARD EASTERN NEBRASKA...THUS INCLUDED A WIND GUST
MENTION WITH TEMPO TSTM GROUP EARLY IN TAF PERIOD AT ALL SITES.
CONVECTION DEVELOPING BEHIND LEADING LINE IN SW NEBR COULD MOVE
ACROSS TAF SITES SUNDAY MORNING AND THIS WILL HAVE TO BE
MONITORED FOR POSSIBLE INCLUSION LATER. HOWEVER...WITH INITIAL
FORECAST ONLY CARRIED A FEW HOUR WINDOW WITH INITIAL THUNDERSTORM
SURGE. GUSTY SOUTH SOUTHEAST SFC WINDS HAVE DEVELOPED AHEAD OF
CONVECTION WILL LIKELY TURN VARIABLE AFTER CONVECTION PASSES
THROUGH. THIS CONVECTION SHOULD AID IN A WEAK FRONT PUSHING
THROUGH KOFK SUNDAY MIDDAY WITH NNW WINDS BEHIND IT. AHEAD OF
BOUNDARY SRLY WINDS AND A PROB30 GROUP WAS CARRIED AT KOMA/KLNK
FOR ADDITIONAL TSTORM DEVELOPMENT LATE SUNDAY AFTERNOON/EVENING.
CHERMOK
&&
.PREV DISCUSSION... /ISSUED 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
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
320 AM MDT SUN JUN 23 2013
.DISCUSSION..
DRYLINE HAS MADE LESS PROGRESS WESTWARD ATTM THAN IN PREVIOUS
NIGHTS...AND AT 3 AM WAS STRETCHED FROM KROW NORTHEAST TO NEAR KCAO.
AT THE SAME TIME...A BOUNDARY FROM APPARENTLY THE CONVECTIVE COMPLEX
OVER WRN NE AND KS...OR AT LEAST AIDED BY IT...HAD SAGGED TO KLHX
AND KLAA. LATEST RUC13 INDICATES THE BOUNDARY COULD REACH KTCC OR
EVEN FARTHER SOUTH BY MIDMORNING...AND BY EARLY AFTERNOON IT COULD
BE STRETCHED FROM THE RATON AREA TO KTCC. 06Z NAM MAKES FOR AN
INTERESTING FORECAST WITH THE SURFACE LOW REMAINING CENTERED NEAR
KLVS RATHER THAN LIFTING INTO NE CO LATE THIS AFTERNOON. THIS CHANGE
COULD RESULT IN A LITTLE LESS WIND...AS WELL AS A LITTLE MORE AREAL
COVERAGE OF THE SLIGHT CHANCE POPS WE CURRENTLY HAVE PAINTED IN FAR
NE NM. OTHERWISE...SHOULD BE LESS HIGH CLOUDS AROUND TODAY WITH
LITTLE CHANGE IN HIGH TEMPERATURES FOR MOST LOCALES.
WINDS TO BE A BIT STRONGER MONDAY...SHUNTING ANY MID LEVEL MOISTURE
THAT TRIES TO WORK IT/S WAY NORTHWARD INTO SOUTHERN AND EASTERN
SECTIONS OF THE STATE...ALTHOUGH IT/S NOW FORECAST TO BE SOMEWHAT
LESS THAN PREVIOUS MODEL RUNS SUGGESTED...AND SEEPAGE INTO SOUTHWEST
NM APPEARS LESS LIKELY. STILL THERE IS PLENTY OF MOISTURE JUST SOUTH
OF THE BORDER SO LEFT POPS PRETTY MUCH ALONE. DRYLINE CAN/T SEEM TO
MAKE MUCH PROGRESS WESTWARD FOR THE NEXT FEW DAYS WITH THE LEE
TROUGH STAYING PUT. UPPER HIGH REMAINS PROGGED TO SHIFT NORTHWARD BY
TUESDAY ALLOWING WINDS TO RELAX...HEADING FOR THE FOUR CORNERS
REGION MID TO LATE WEEK. WEDNESDAY INTO THURSDAY COULD BE THE
HOTTEST DAYS OF THE WEEK FOR THE CENTRAL AND WEST. EVIDENCE OF A
FRONT INVADING THE EASTERN PLAINS FRIDAY-ISH COULD SPARK SHOWERS AND
STORMS IN THE NORTH CENTRAL/EAST. BY NEXT WEEKEND...THE HIGH CENTER
STARTS TRIPPING TOWARD SALT LAKE...WITH POTENTIAL FOR CONVECTION TO
DEVELOP OVER THE NRN HIGH TERRAIN AND DRIFT SOUTH TO SOUTHWESTWARD
INTO CENTRAL/WRN VALLEYS.
&&
.FIRE WEATHER...
...CRITICAL FIRE WEATHER CONDITIONS EXPECTED OVER MUCH OF CENTRAL TO
EASTERN NM TODAY WITH MORE WIDESPREAD CONDITIONS ON MONDAY...
TODAY`S FORECAST WILL BE TRICKY...ESPECIALLY WITH REGARDS TO THE
WINDS. THIS WILL HAVE LARGE IMPLICATIONS ON THE DURATION AND SPATIAL
EXTENT OF CRITICAL FIRE WEATHER THIS AFTERNOON. OVERALL...THE MAIN
FEATURES THAT HAVE BEEN DICTATING THE WEATHER PATTERN THE PAST FEW
DAYS ARE STILL AT WORK...WITHOUT ANY BLATANT OR LARGE CHANGES. ANY
DIFFERENCES WILL BE FAIRLY SUBTLE. HOWEVER...MIXING HEIGHTS MAY
EXCEED YESTERDAY`S LEVELS DUE TO LESS HIGH CIRRUS CLOUDS. MODEL
DEPICTION OF MIXING HEIGHTS IS RATHER SPLOTCHY...INDICATIVE THAT IT
IS HAVING DIFFICULTY RESOLVING IT. ALSO...SOUTHWESTERLIES ALOFT
REMAIN RELATIVELY STRONG FOR LATE JUNE...HOSTING SPEEDS OF 15-20 KT
AT H7 AND UP TO 20-25 KT AT H5 WHICH SHOULD BE WITHIN THE MIXED
LAYER OF MOST SITES. THE EASTERN HALF OF THE FORECAST AREA WILL ALSO
HAVE POTENTIAL FOR A BETTER SURFACE PRESSURE GRADIENT...DEPENDING ON
WHERE THE LEE SIDE SURFACE LOW ESTABLISHES ITSELF. A CLUSTER OF
CONVECTION IN THE CENTRAL PLAINS OF THE NATION HAS HELPED USHER A
BOUNDARY SOUTHWARD INTO COLORADO. IF THIS BOUNDARY SPILLS FARTHER
SOUTH INTO NM...BEYOND WHAT MOST MODELS ARE INDICATING...IT COULD
WREAK HAVOC ON WIND FORECAST DUE TO ORIENTATION OF THE SURFACE LOW
AND ASSOCIATED GRADIENT. HUMIDITY WILL TANK LESS THAN 10 PERCENT
OVER MOST OF THE FORECAST AREA TODAY WITH THE FAR EASTERN PLAINS
NEAR TX BEING THE ONLY EXCEPTION. HIGHLY UNSTABLE AND WELL-MIXED
AIRMASS WOULD SEEM TO SUPPORT A GUSTY DAY FOR MUCH OF THE AREA...AND
BEST CONFIDENCE FOR CRITICAL WINDS EXTENDS ALONG AND EAST OF A
SOCORRO TO CLINES CORNERS TO RATON LINE...EXCLUDING SOME OF THE FAR
PLAINS ALONG THE OK/TX BORDERS. HAVE THROWN IN MIDDLE RIO GRANDE
FWZ106 TO THE WARNING. WOULD NOT BE SURPRISED TO SEE A COUPLE OF
STRAY GUSTS TO 35 MPH IN THE WEST CENTRAL ZONES...BUT CONFIDENCE IS
NOT HIGH ENOUGH TO PULL TRIGGER ON WARNING.
CONFIDENCE IS A BIT HIGHER ON MONDAY DUE TO STRONGER WIND SIGNALS
SUCH AS BETTER AGREEMENT ON THE SURFACE LOW PLACEMENT AND STRONGER
WINDS ALOFT OF 20 TO 35 KT IN THE H7-H5 LAYER. VERY DRY AIRMASS
ALOFT AND REINFORCEMENT FROM A MID LEVEL DRY SLOT WILL MAKE ANOTHER
EXTREMELY LOW RH REGIME WITH POOR RECOVERIES MONDAY MORNING AND
PROLONGED SINGLE DIGIT READINGS. HAVE EXTENDED WATCH FOR MONDAY TO
INCLUDE MIDDLE RIO GRANDE AND NORTHWESTERN AND WEST CENTRAL
HIGHLANDS/MOUNTAINS. HAVE LEFT NORTHERN MOUNTAINS AND NORTHWEST
PLATEAU OUT DUE TO LOWER CONFIDENCE IN THE WINDS...BUT THIS WILL
NEED TO BE SCRUTINIZED OVER THE NEXT 24 HOURS.
THE WINDS ALOFT DO RELAX SOME INTO TUESDAY AS THE UPPER HIGH BEGINS
TO DRIFT NORTHWARD. STILL...A SUFFICIENT LEE SIDE SURFACE LOW WILL
KEEP SOME BREEZY/WINDY CONDITIONS GOING IN THE EAST...PRIMARILY NEAR
THE I-40 CORRIDOR. INTO WEDNESDAY AND THROUGH THE REST OF THE WEEK
THE UPPER HIGH WILL ESTABLISH ITSELF OVER THE DESERT
SOUTHWEST...PERIODICALLY CENTERING NEAR OR CLOSE TO THE FOUR
CORNERS. THIS WILL SPELL DRY AND HOT CONDITIONS...BUT WITH LOW
WINDS. MOISTURE MAY FINALLY BEGIN TO ARRIVE FROM THE EAST BY THE
WEEKEND AS A BACK DOOR FRONT AND ONSHORE FLOW FROM THE GULF OF
MEXICO SEEP IN.
52
&&
.AVIATION...
06Z TAF CYCLE
VFR CONDITIONS WILL PREVAIL FOR THE NEXT 24 HOURS. DRYLINE IS
CURRENTLY RETREATING AND STRONG S/SE WINDS WITH GUSTS NEAR 30KTS
ARE ALSO RETURNING EAST OF THE DRYLINE. THESE GUSTS WILL BE
POSSIBLE THROUGH APPROXIMATELY 10Z MAINLY ALONG AND EAST OF A
KCAO TO KROW LINE. ON SUNDAY...W/SW WINDS WILL INCREASE BY LATE
MORNING...WITH GUSTS BETWEEN 20 AND 35KTS LIKELY DURING THE
AFTERNOON. DRYLINE SHOULD MIX BACK OUT TO AT LEAST THE TX
BORDER...LIMITING TS POTENTIAL TO ALL AREAS EXCEPT PERHAPS ROOSEVELT
COUNTY. THE DRYLINE WILL RETREAT AGAIN SUNDAY NIGHT...WITH GUSTY
S/SE WINDS RETURNING TO THE EAST OF IT.
34
&&
.PRELIMINARY POINT TEMPS/POPS...
FARMINGTON...................... 92 51 92 51 / 0 0 0 5
DULCE........................... 88 40 89 41 / 0 0 5 5
CUBA............................ 87 45 86 45 / 0 0 5 5
GALLUP.......................... 88 45 87 44 / 0 0 5 5
EL MORRO........................ 87 43 86 43 / 0 0 5 5
GRANTS.......................... 89 47 89 46 / 0 0 5 5
QUEMADO......................... 89 47 89 46 / 0 0 5 5
GLENWOOD........................ 96 50 94 55 / 0 0 5 5
CHAMA........................... 80 43 80 43 / 0 0 5 5
LOS ALAMOS...................... 86 54 87 53 / 0 0 5 5
PECOS........................... 82 56 83 55 / 5 5 5 5
CERRO/QUESTA.................... 85 49 84 48 / 0 0 5 5
RED RIVER....................... 80 41 80 41 / 0 0 5 5
ANGEL FIRE...................... 80 42 81 43 / 0 0 5 5
TAOS............................ 87 43 86 43 / 0 0 5 5
MORA............................ 82 51 83 52 / 5 5 5 5
ESPANOLA........................ 92 48 92 49 / 0 0 5 5
SANTA FE........................ 89 50 89 50 / 0 0 5 5
SANTA FE AIRPORT................ 92 52 92 52 / 0 0 5 5
ALBUQUERQUE FOOTHILLS........... 93 60 93 60 / 0 0 5 5
ALBUQUERQUE HEIGHTS............. 96 62 95 62 / 0 0 5 5
ALBUQUERQUE VALLEY.............. 98 55 96 56 / 0 0 5 5
ALBUQUERQUE WEST MESA........... 98 57 95 57 / 0 0 5 5
LOS LUNAS....................... 96 59 97 59 / 0 0 5 5
RIO RANCHO...................... 95 60 95 59 / 0 0 5 5
SOCORRO......................... 101 64 100 64 / 0 0 5 5
SANDIA PARK/CEDAR CREST......... 89 57 91 57 / 0 0 5 5
TIJERAS......................... 92 58 93 57 / 0 0 5 5
MORIARTY/ESTANCIA............... 91 53 91 52 / 5 5 5 5
CLINES CORNERS.................. 89 56 89 55 / 5 5 5 5
GRAN QUIVIRA.................... 92 58 92 58 / 5 5 10 5
CARRIZOZO....................... 93 63 93 64 / 5 5 10 5
RUIDOSO......................... 87 53 87 57 / 10 10 10 20
CAPULIN......................... 90 52 90 51 / 5 5 5 5
RATON........................... 93 53 93 52 / 5 5 5 5
SPRINGER........................ 91 53 92 51 / 5 5 5 5
LAS VEGAS....................... 89 52 90 53 / 5 5 5 5
CLAYTON......................... 96 61 97 61 / 20 10 5 10
ROY............................. 93 58 94 56 / 5 5 5 5
CONCHAS......................... 97 60 98 59 / 5 5 5 10
SANTA ROSA...................... 98 62 98 61 / 0 5 5 10
TUCUMCARI....................... 102 68 103 67 / 5 5 10 10
CLOVIS.......................... 98 64 97 64 / 10 10 20 10
PORTALES........................ 99 65 98 65 / 20 10 20 10
FORT SUMNER..................... 100 66 100 65 / 5 5 10 10
ROSWELL......................... 105 69 104 68 / 20 10 20 10
PICACHO......................... 95 63 96 63 / 10 10 10 10
ELK............................. 90 62 91 63 / 10 10 10 20
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 1 PM THIS AFTERNOON TO 8 PM MDT THIS EVENING
FOR THE FOLLOWING ZONES...NMZ102>104-106>108.
FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING FOR
THE FOLLOWING ZONES...NMZ102>109.
&&
$$
AREA FORECAST DISCUSSION
NWS RALEIGH NC
300 AM EDT SUN JUN 23 2013
.SYNOPSIS...
WEAK LOW PRESSURE OVER EASTERN NORTH CAROLINA WILL GRADUALLY
DISSIPATE TODAY. A SURFACE TROUGH WILL LINGER OVER THE PIEDMONT
THROUGH MID WEEK... AS A WARM AND MOIST AIR MASS HOLDS OVER THE
REGION.
&&
.NEAR TERM /THROUGH MONDAY NIGHT/...
AS OF 300 AM SUNDAY...
THE WAVE OF LOW PRESSURE THAT MOVED THROUGH EASTERN NC LAST EVENING
IS NOW MOVING INTO SOUTH CENTRAL VA...AND THE BULK OF HEAVY RAIN ON
ITS EASTERN FLANK IS EXITING THE NORTHERN COASTAL PLAIN. IN ITS
WAKE...A WEAK BOUNDARY LINGERS NEAR THE I-95 CORRIDOR...WHERE A FEW
SHOWERS AND THUNDER STORMS CONTINUE TO DEVELOP. HRRR SIM
REFLECTIVITY SUGGEST PRECIP WILL EVENTUALLY SHIFT NORTHWESTWARD INTO
THE PIEDMONT THIS MORNING AS AN UPPER LEVEL LOW OVER THE TN VALLEY
LIFTS ALONG THE APPALACHIANS. AS THE DAY WEARS ON...A BROAD
SOUTH-SOUTHEASTERLY LOW LEVEL FLOW WILL DOMINATE AS THE BERMUDA HIGH
BECOMES ESTABLISHED. MOISTURE CONVERGENCE IN THE VICINITY OF THE
WEAK BOUNDARY SHOULD BE THE MAIN FOCUS FOR WHAT WILL OTHERWISE BE
SCATTERED SHOWERS AND STORMS IN AN ENVIRONMENT CHARACTERIZED BY PW
AROUND 1.8 INCHES AND MLCAPE OF 500-1000 J/KG. HIGHS SHOULD REACH
THE MID 80S UNDER PARTLY TO MOSTLY CLOUDY SKIES.
TONIGHT...
A FEW SHOWERS MAY LINGER INTO THE EVENING HOURS...BUT CONVECTION
SHOULD BE MOSTLY DIURNAL IN NATURES. LOW CLOUDS ARE EXPECTED ONCE
AGAIN OVERNIGHT AND LOWS WILL FALL ONLY INTO THE UPPER 60S.
MONDAY AND MONDAY NIGHT...
MOIST SOUTHERLY FLOW WILL CONTINUE ON MONDAY WITH UPPER LEVEL
HEIGHTS SLOWLY BUILDING OVER THE WESTERN ATLANTIC AND
WEST-SOUTHWESTERLY FLOW ALOFT OVER NC. A WEAK LEE TROUGH WILL BEGIN
TO DEVELOP OVER THE PIEDMONT...BUT ITS NOT APPARENT HOW MUCH OF A
FOCUS THIS WILL BE FOR AFTERNOON CONVECTION.
THERMODYNAMICALLY...THE ATMOSPHERE WILL BE VERY SIMILARLY TO
SUNDAY...WITH WEAK LAPSE RATES AND MLCAPE POSSIBLY APPROACHING 1000
J/KG ACROSS THE SOUTH AND EAST. PW WILL REMAIN WELL ABOVE 1.5
INCHES...SUGGESTING SCATTERED SHOWERS AND STORMS WILL BE POSSIBLE.
HIGHS WILL BE A COUPLE DEGREES WARMER THAN SUNDAY AS THE UPPER RIDGE
BUILDS CLOSER TO THE COAST...85-89. LOWS MONDAY NIGHT IN THE UPPER
60S AND LOWER 70S.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 240 AM SUNDAY...
FOR TUESDAY/TUESDAY NIGHT: THE MID LEVEL ANTICYCLONE NOW CENTERED
OVER THE WRN ATLANTIC WILL HAVE EVOLVED INTO A WEAKER BUT MORE
EXPANSIVE RIDGE COVERING MUCH OF THE SOUTHERN HALF OF THE COUNTRY
(WEST COAST EXCEPTED) BY TUESDAY... RESULTING IN A WEAK WNW STEERING
FLOW OVER NC AND POOR DEEP LAYER SHEAR AS THE WESTERLIES RETREAT
WELL TO THE NORTH. MODERATE TO POTENTIALLY HIGH INSTABILITY IS
EXPECTED BY AFTERNOON WITH GFS-PROJECTED MLCAPE OF 2000-2800 J/KG
PARTICULARLY OVER THE EASTERN AND SOUTHERN PORTIONS OF CENTRAL NC...
SUPPORTIVE OF AT LEAST SCATTERED SHOWERS AND STORMS WITH DAYTIME
HEATING GIVEN PRECIP WATER VALUES OF 1.6-2.0 INCHES... 150-180
PERCENT OF NORMAL. AN MCV INDICATED BY THE MODELS OVER NEB EARLY
MONDAY MORNING IS EXPECTED TO TRACK ACROSS MI/IN/OH BY TUESDAY
MORNING BEFORE TRACKING ACROSS THE MID ATLANTIC REGION LATE
TUESDAY/TUESDAY NIGHT. THIS ADDED DYNAMIC FORCING FOR ASCENT FROM
DPVA (ALBEIT WEAK) COULD RESULT IN BETTER COVERAGE OF CONVECTION IN
AND NEAR AND EAST OF THE SURFACE LEE TROUGH LATE AFTERNOON THROUGH
THE EVENING. WILL GRADUALLY INCREASE POPS THROUGH THE AFTERNOON TO
40-50 PERCENT... CONTINUING AND SPREADING WEST TO EAST THROUGH THE
EVENING BEFORE TAPERING BACK DOWN TO SLIGHT CHANCES OVERNIGHT... AS
WE HANG ON TO A WARM MOIST AIR MASS AND AT LEAST MARGINAL
INSTABILITY. THICKNESSES SHOULD BE VERY CLOSE TO NORMAL...
INDICATIVE OF HIGHS 85-90 WITH SKIES VARYING BETWEEN PARTLY AND
MOSTLY CLOUDY. MILD LOWS OF 67-73 WITH INCREASING MID AND HIGH
CLOUDS OVERNIGHT AS THE MCV APPROACHES.
FOR WEDNESDAY/WEDNESDAY NIGHT: EXPECT A COUPLE OF SHOWERS AND AN
ISOLATED STORM OR TWO TO PERSIST INTO WEDNESDAY MORNING GIVEN THE
VERY MOIST (PW OF 1.5-1.9 IN.) AND SOMEWHAT UNSTABLE (MLCAPE OF
1000-1500 J/KG) ENVIRONMENT EVEN EARLY IN THE DAY... WITH THE
PERSISTENT LEE TROUGH EXTENDING THROUGH CENTRAL NC AND SUBTLE
WEAKNESS ALOFT OVER ERN NC. THE WEAK WIND FIELD AND LACK OF DISTINCT
SHARP FEATURES TO FOCUS CONVECTION RESULTS IN A FORECAST WITH HIGH
CONFIDENCE IN AT LEAST SCATTERED SHOWERS/STORMS BUT LITTLE
CONFIDENCE IN THE DETAILS OF EXACTLY WHO IS MOST LIKELY TO SEE RAIN
IN CENTRAL NC. PRECIP WATER REMAINS HIGH ANOMALOUSLY HIGH AND THE
GFS TRANSLATES THE STEADILY RISING THICKNESSES AND WARMING SURFACE
TEMPS TO GREATER INSTABILITY... 2200-3000 J/KG OF MLCAPE ESPECIALLY
FROM HIGHWAY 1 EAST. EXPECT ANOTHER ROUND OF GOOD CHANCE POPS
FOCUSED ON THE AFTERNOON AND EVENING... AND AS SHOULD BE THE CASE
TUESDAY... THE WEAK WIND FIELD WILL LEAD TO MEANDERING AND
UNORGANIZED MULTICELL CONVECTION. HIGHS 87-92 AND LOWS 69-73. -GIH
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 250 AM SUNDAY...
EVOLUTION TOWARD A MORE AMPLIFIED PATTERN OVER NOAM WILL OCCUR AS WE
HEAD INTO THE WEEKEND. A MID LEVEL ANTICYCLONE WILL STRENGTHEN OVER
THE FOUR CORNERS REGION IN RESPONSE TO A POWERFUL VORTEX OVER THE
NORTHEAST PACIFIC NEAR 47N/140W... WHICH EJECTS SHORTWAVE ENERGY
INTO CENTRAL CANADA AND A MID LEVEL JET ACROSS THE DAKOTAS. THE
RESULTING FALLING HEIGHTS OVER ONTARIO CULMINATE IN A CLOSED LOW
OVER MI OVER THE WEEKEND AND A TREND TOWARD DEEPENING LONGWAVE
TROUGHING OVER THE EASTERN HALF OF THE CONUS OVER THE WEEKEND.
PRECIP WATER SHOULD REMAIN ABOVE NORMAL THROUGH THE PERIOD WITH
SHARPENING OF THE SURFACE TROUGH THROUGH CENTRAL NC AND AN
INCREASING WNW MID LEVEL FLOW... FACILITATING GREATER ORGANIZATION
OF SHOWERS/STORMS AS WE HEAD INTO THE WEEKEND. GIVEN THIS IMPROVING
SHEAR AND LITTLE EXPECTED CHANGE IN THE MOISTURE AND THERMAL PROFILE
OVER THE AREA... WILL HOLD ONTO DAILY SCATTERED SHOWERS AND
STORMS... MAINLY AFTERNOON AND EVENING. LOW LEVEL THICKNESSES HOLD
SLIGHTLY ABOVE NORMAL... SO EXPECT HIGHS IN THE MID 80S TO AROUND
90. WARM LOWS IN THE UPPER 60S TO LOWER 70S. -GIH
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 150 AM SUNDAY...
POOR AVIATION CONDITIONS WILL CONTINUE THIS MORNING...THOUGH
CONDITIONS WILL LIKELY VARY FROM LIFR TO MVFR. CONFIDENCE IN HOW
QUICKLY LOW CEILINGS WILL DEVELOP REMAINS UNCERTAIN...THOUGH IFR
CEILINGS ARE BEGINNING TO SHOW UP AROUND KFAY...AND SHOULD EXPAND
NORTHWARD THROUGH 09Z. MEANWHILE...AN UPPER LEVEL LOW MOVING
NORTHEAST ALONG THE APPALACHIANS WILL CONTINUE TO SUPPORT A FEW
ISOLATED SHOWERS AND STORMS...MAINLY IN THE VICINITY OF A WEAK
BOUNDARY EXTENDING FROM KFAY TO KRWI TO KIXA.
THE ATMOSPHERE OVER CENTRAL NC WILL CONTINUE TO BE VERY MOIST
TODAY...CAUSING CEILINGS TO LIFT SLOWLY AFTER SUNRISE. MVFR
CONDITIONS ARE EXPECTED BY 15-16Z...WITH VFR CONDITIONS POTENTIALLY
DEVELOPING BY 18Z WITH A LIGHT SOUTHERLY WIND. SCATTERED SHOWERS AND
STORMS WILL STILL BE POSSIBLE...THOUGH CONFIDENCE IN LOCATION AND
TIMING IS MUCH TOO LOW FOR MENTION IN TAFS.
OUTLOOK...
WARM AND MOIST SOUTHERLY FLOW AROUND A BERMUDA HIGH WILL BRING
UNSETTLED WEATHER FOR MUCH OF THE WEEKEND...WITH SUB-VFR CONDITIONS
POSSIBLE EACH MORNING AND SCATTERED SHOWERS/STORMS IN THE AFTERNOON
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...BLS
SHORT TERM...HARTFIELD
LONG TERM...HARTFIELD
AVIATION...BLS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
351 AM CDT SUN JUN 23 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 320 AM CDT SUN JUN 23 2013
THE HIGHLIGHT OF THE SHORT TERM ARE CONVECTIVE CHANCES FOR TODAY.
CURRENTLY...WIDESPREAD LIGHT TO MODERATE RAIN WITH EMBEDDED
THUNDERSTORMS CONTINUES ACROSS MOST OF NORTHERN NORTH DAKOTA IN
ASSOCIATION WITH THE RIGHT ENTRANCE REGION OF THE UPPER LEVEL JET
STREAK AHEAD OF THE STRONG SHORTWAVE. AS THIS WAVE CONTINUES TO
PROPAGATE TO THE NORTHEAST THROUGH THE MORNING AND AFTERNOON...THE
AREA OF MORE WIDESPREAD PRECIPITATION ACROSS NORTHERN NORTH DAKOTA
WILL BECOME FOCUSED INTO MANITOBA. HOWEVER...WITH CLEARING SKIES
EXPECT SURFACE DESTABILIZATION AND THE DEVELOPMENT OF DIURNALLY
DRIVEN SCATTERED SHOWERS AND THUNDERSTORMS AS DEPICTED BY THE 00
UTC 4KM WRF AND THE 06 UTC HRRR AREA WIDE. DO NOT ANTICIPATE
WIDESPREAD SEVERE THUNDERSTORMS...HOWEVER...ML CAPE VALUES NEAR
1000 J/KG AND DEEP LAYER SHEAR OF 30-35 KTS SUGGEST THE POTENTIAL
FOR MARGINAL SEVERE HAIL WITH THE STRONGER STORMS. CONVECTION IS
EXPECTED TO QUICKLY FADE WITH SUNSET...WITH FOG POSSIBLE WITH
CLEAR SKIES AND LIGHT WINDS IN A WEAK SURFACE RIDGE AXIS TONIGHT.
DID CANCEL THE FLASH FLOOD WATCH THAT WAS IN EFFECT FOR THE JAMES
RIVER VALLEY AND PORTIONS OF FAR SOUTH CENTRAL NORTH DAKOTA. WHILE
SCATTERED THUNDERSTORMS ARE POSSIBLE TODAY...THE THREAT FOR FLASH
FLOODING IS NO LONGER ANTICIPATED. SEE THE HYDROLOGY DISCUSSION
FOR DETAILS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 320 AM CDT SUN JUN 23 2013
THE MAIN FOCUS TODAY IS ON THE POTENTIAL FOR STRONG/SEVERE
THUNDERSTORMS MONDAY THROUGH TUESDAY NIGHT.
ANOTHER LOW PRESSURE SYSTEM IS SCHEDULED TO MOVE ACROSS THE NORTHERN
PLAINS TUESDAY AS THE FOUR CORNERS MID/UPPER LEVEL RIDGE AND
NORTHEASTERN PACIFIC MID/UPPER LEVEL TROUGH MAINTAIN A BELT OF
WESTERLIES ACROSS THE NORTHERN ROCKIES AND DAKOTAS. THE 00 UTC
NAM/ECMWF/GFS/GEM GLOBAL ALL AGREE ON GENERAL TIMING OF THE
SYSTEM...BUT THERE IS SIGNIFICANT SPREAD ON THE TIMING/LOCATION OF
ASSOCIATED CONVECTION. THE UNCERTAINTY ASSOCIATED WITH COMPLEX
MESOSCALE INTERACTIONS IS LARGE...SO THERE IS NO EASY WAY TO PICK
THE SINGLE MODEL SOLUTION MOST LIKELY TO VERIFY. THUS...FORECASTS
USED A CONSENSUS BLEND OF ALL AVAILABLE UTC MODELS/ENSEMBLES.
THE STORM PREDICTION CENTER FORECAST FROM THEIR OUTLOOKS CALLS
FOR LATE AFTERNOON CONVECTION ALONG THE MT/ND BORDER LOOKS TO FORM
AN MCS THAT PROPAGATES INTO THE CENTRAL PLAINS ON MONDAY NIGHT.
CONVECTION LOOKS TO REGENERATE OVER CENTRAL NORTH DAKOTA ON TUESDAY
FOR ANOTHER ROUND IN CENTRAL AND EASTERN COUNTIES.
THEREAFTER...00 UTC MODELS/ENSEMBLES GENERALLY AGREE ON A MORE
DIURNAL NATURE FOR THE ISOLATED CONVECTION THAT DOES INITIATE AMIDST
STRONGER RIDGING ALOFT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 320 AM CDT SUN JUN 23 2013
LIGHT TO MODERATE RAIN WITH EMBEDDED THUNDERSTORMS WILL CONTINUE
AT KISN...KMOT AND KJMS THIS MORNING...WITH ACTIVITY BECOMING
SCATTERED ACROSS ALL OF WESTERN AND CENTRAL NORTH DAKOTA THROUGH
THE AFTERNOON. GIVEN THE NEAR SATURATED SURFACE OBSERVATIONS THIS
MORNING...POCKETS OF MVFR/IFR FOG AND STRATUS IS POSSIBLE.
&&
.HYDROLOGY...
ISSUED AT 320 AM CDT SUN JUN 23 2013
DID CANCEL THE FLASH FLOOD WATCH THAT WAS IN EFFECT FOR THE JAMES
RIVER VALLEY AND PORTIONS OF SOUTH CENTRAL NORTH DAKOTA. WHILE
SCATTERED THUNDERSTORMS ARE POSSIBLE TODAY...MUCH LOWER
PRECIPITABLE WATER VALUES AND LOWER CONVECTIVE COVERAGE NEGATES
THE FLASH FLOOD THREAT. HOWEVER...WILL HAVE TO MONITOR THESE AREAS
AGAIN MONDAY AND TUESDAY AS STRONG TO SEVERE THUNDERSTORMS ARE
POSSIBLE WITH THE RETURN OF DEEP MOISTURE.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...AYD
LONG TERM...SCHECK
AVIATION...AYD
HYDROLOGY...AYD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
348 AM CDT SUN JUN 23 2013
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 345 AM CDT SUN JUN 23 2013
THE MAIN CHALLENGE THIS MORNING WILL BE SEVERE STORM THREAT TODAY
AND MORE STORMS POSSIBLE MON NIGHT AND TUE. MODELS ARE IN GOOD
OVERALL AGREEMENT...AND WILL FOLLOW THE HRRR INITIALLY THEN SIDE
WITH THE CONSISTENT GFS.
FOR TODAY...EXPECT AN MCS TO BE ONGOING THIS MORNING MOVING FROM
SW TO NE. THERE COULD BE LOCALLY HEAVY RAINFALL THIS MORNING IN
THE SOUTH...AND THIS AREA IS QUITE SATURATED SO WILL CONTINUE WITH
THE FLASH FLOOD WARNING UNTIL 12Z. THERE COULD BE A MORE ORGANIZED
SEVERE THREAT BY EARLY AFTERNOON MAINLY IN THE MN COUNTIES ALONG A
COLD FRONT...MLCAPE TO AROUND 2000 J/KG AND AMPLE DEEP LAYERED
SHEAR. THE MAIN THREATS SHOULD BE LARGE HAIL AND DAMAGING WINDS.
FOR TONIGHT...ANY CONVECTION SHOULD QUICKLY MOVE OUT OF THE
EASTERN AREAS DURING THE EVENING. DRIER AIR WILL ADVECT INTO THE
REGION WITH GENERAL LIGHT WINDS. WILL HAVE TO WATCH FOR PATCHY FOG
IN AREAS THAT GET RAIN...BUT FOR NOW WON/T MENTION WITH AREAL
COVERAGE NOT CERTAIN.
ON MONDAY...EXPECT A DRY AND WARM DAY WITH 850MB TEMPS WARMING TO
AROUND +18C. MOISTURE PROFILES WILL BEGIN TO INCREASE BY AFTERNOON
IN THE WEST AHEAD OF THE NEXT SHORTWAVE.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 345 AM CDT SUN JUN 23 2013
FOR MONDAY NIGHT AND TUE...THE THREAT FOR SHOWERS AND STORMS WILL
ONCE AGAIN INCREASE WITH SHORTWAVE ENERGY MOVING THROUGH GENERAL
SW FLOW ALOFT. TIMING STILL REMAINS A QUESTION...BUT THE SEVERE
THREAT COULD ALSO INCREASE AT LEAST IN THE WEST ON TUE...AND WILL
FEEL LIKE SUMMER WITH TEMPS ABOVE NORMAL AND PLENTY OF MOISTURE IN
PLACE.
FOR WEDNESDAY THROUGH SATURDAY...A LONG WAVE TROUGH AXIS DEVELOPS
OVER THE EASTERN PACIFIC AND THE EASTERN US WHILE A LONG WAVE
RIDGE DEVELOPS OVER THE NORTHERN ROCKIES AND INTO THE CANADIAN
ROCKIES. PATTERN BECOMES MORE NORTHWEST FLOW ALOFT WITH TIME.
ECMWF BEGINS THE PERIOD AS A FASTER SOLUTION THAN THE GFS. THE ECMWF
MAINTAINS A CONSISTENT FAST BIAS THROUGH THE PERIOD. THE ECMWF HAS
TRENDED WITH FASTER SOLUTIONS OVER THE LAST FEW MODEL RUNS WHILE
THE GFS HAS TRENDED SLOWER. WILL BLEND THE TWO MODELS AND WILL SPEED
UP PRECIPITATION A BIT FROM TODAYS RUN AND MAY KEEP YESTERDAYS RUN
WITH SOME TIME PERIODS.
LITTLE CHANGE TO TEMPS THIS PERIOD FROM YESTERDAYS RUN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1151 PM CDT SAT JUN 22 2013
BESIDES SOME THUNDER THREAT...MAIN ISSUE NOW IS AREA OF LOW CLOUDS
THAT IS MOVING WEST FROM LAKE SUPERIOR INTO THE ERN FCST AREA. HOW
FAR THAT WILL GET IS UNKNOWN BUT COULD BE INTO VALLEY LATER
TONIGHT SO DID INCLUDE SOME IFR OR LOW END MVFR CIGS DUE TO LIGHT
WINDS AND HUMID CONDITIONS. MAIN THREAT FOR RAIN AND STORMS EARLY
ON DVL REGION WILL SPREAD INTO THE RRV 10Z-17Z THEN INTO ERN FCST
AREA AS FRONT MOVES THROUGH. WINDS WILL TURN WEST BEHIND FRONT
MIDDAY TO AFTN WITH GUSTS TO 20+KTS AT DVL-FAR-GFK PSBL.
&&
.HYDROLOGY...
ISSUED AT 345 AM CDT SUN JUN 23 2013
RIVER RISES CONTINUE IN THE SOUTHERN VALLEY AND WAHPETON IS
NEARING A CREST NEAR MODERATE FLOOD STAGE. ADDITIONAL HEAVY
RAINFALL IS OCCURRING ACROSS PORTIONS OF THE SOUTHERN BASIN THIS
MORNING...AND ADDITIONAL LOCAL RISES WILL NEED TO BE MONITORED WITH
HEAVY RAIN RATES EXPECTED.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...FLASH FLOOD WATCH UNTIL 7 AM CDT THIS MORNING FOR NDZ014-024-
028>030-038-039-049-052-053.
MN...FLASH FLOOD WATCH UNTIL 7 AM CDT THIS MORNING FOR MNZ002-003-
022>024-027>032-040.
&&
$$
SHORT TERM...DK
LONG TERM...HOPPES/DK
AVIATION...RIDDLE
HYDROLOGY...DK
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
224 AM CDT SUN JUN 23 2013
.DISCUSSION...
RADAR SCOPE PPINE AS OF 07Z FOLLOWING AN ISOLATED THUNDERSTORM OVER
DAVIDSON COUNTY BACK BEFORE MIDNIGHT. 850 MBAR DEWPOINTS POOLED
ACROSS DAVIDSON COUNTY ON THE RUC BETWEEN 03Z AND 05Z POSSIBLY
CONTRIBUTING TO THE FORMATION OF THE STORM. AT THE SAME TIME UPPER
LEVEL LOW WAS SPINNING OVER EASTERN TENNESSEE. UK/NAM/GFS/GFSENSEMBLE
AND ECMWF ALL SHOW THIS LOW LIFTING NORTH TODAY WITH BROAD UPPER
RIDGE DEVELOPING OVER THE SOUTHERN US. THIS MEANS A SUMMER PATTERN
WITH BERMUDA HIGH RIDGING IN OVER THE SOUTHEASTERN US FOR THE NEXT
SEVERAL DAYS. BY THE LATTER PART OF THE WORK WEEK THE UPPER LEVEL
HIGH WILL BE CENTERED OVER THE WESTERN US WITH TROUGHING OVER THE
EASTERN US...BOTH EURO/ENSEMBLE AND GFS SHOW THIS DEVELOPING. WE
ARE BASICALLY LOOKING AT SUMMER TYPE CONVECTION THAT COULD ALSO OCCUR
NOCTURNALLY THIS TIME OF THE YEAR. AS THE TROUGH DEVELOPS OVER THE
EASTERN US ON THURSDAY WE DO HAVE A FRONT DROPPING DOWN THIS WAY
BUT SEEMS TO HAVE A HARD TIME GETTING VERY FAR SOUTH. TEMPS DO
LOOK TO BACK OFF A LITTLE BY SUNDAY. OTHERWISE...LOOK FOR WARM
DAYS AND NOT MUCH RELIEF AT NIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 90 70 88 70 / 20 20 30 30
CLARKSVILLE 90 69 87 69 / 20 20 20 20
CROSSVILLE 84 65 83 65 / 20 20 30 30
COLUMBIA 90 69 89 70 / 20 20 30 30
LAWRENCEBURG 90 68 90 69 / 20 20 30 30
WAVERLY 90 69 88 70 / 20 20 20 20
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
BOYD
01
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1148 PM CDT SAT JUN 22 2013
.AVIATION...
CONTINUED VFR CONDITIONS WITH MODEST SOUTHWEST FLOW ALOFT AND
SURFACE TROUGH OVER THE HIGH PLAINS. THUNDER CHANCES MAY DEVELOP
NEAR KLBB AGAIN SUNDAY LATE AFTERNOON AND EVENING...NOT CERTAIN
ENOUGH TO INCLUDE MENTION AT THIS TIME IN THE TAFS. RMCQUEEN
&&
.PREV DISCUSSION... /ISSUED 915 PM CDT SAT JUN 22 2013/
UPDATE...
RETAINED ISOLATED THUNDER THIS EVENING ONLY IN THE SOUTHWESTERN
SOUTH PLAINS WHERE SHOWERS HAVE AT LEAST BEEN FLIRTING WITH THE
AREA. OTHERWISE...LATEST SHORT-TERM GUIDANCE HAS CONFIRMED MOST
TRENDS THAT THUNDER CHANCES CONTINUE TO DWINDLE. UPDATED FOR LOWER
THUNDERSTORM CHANCES AND REMOVAL OF SEVERE WORDING FOR THIS
EVENING. RMCQUEEN
PREV DISCUSSION... /ISSUED 723 PM CDT SAT JUN 22 2013/
UPDATE...
THUNDERSTORM OPPORTUNITIES APPEAR DIMINISHING WITH DECREASING
CUMULUS FIELD TO OUR SOUTHWEST...OVERSPREADING HIGH CLOUDS WITH
SLOWLY FALLING TEMPERATURES...AND STILL 40 TO 60 JOULES PER
KILOGRAM OF CONVECTIVE INHIBITION TO OVERCOME. LATEST RAP SPREADS
EVEN HIGHER INHIBITION AIRMASS INTO THE AREA BY 02Z-03Z WITH
LATEST RUN INDICATING ONLY VERY ISOLATED STORMS IN THE NEXT HOUR OR
TWO....WHILE THE HRRR HAS BEEN FAR OVERDONE AND TOO FAST WITH
DEVELOPMENT TO OUR NORTH...BUT AT LEAST HAS BEEN PLAYING DOWN
THUNDER DEVELOPMENT OVER MUCH OF THE SOUTH PLAINS AREA. CONVECTIVE
ENERGY SHOULD IT BE RELEASED AND COMBINED WITH 30-35 KNOTS OF DEEP
LAYER SHEAR WOULD INDICATE A POTENTIAL FOR SEVERE STORMS YET...SO
WE WILL MAINTAIN CURRENT FORECAST OF LOW THUNDER CHANCES FOR NOW.
RMCQUEEN
AVIATION...
VFR WITH MODERATE SURFACE TROUGH AND UPPER LEVEL SOUTHWEST FLOW
WILL DOMINATE. THUNDER CHANCES APPEAR ONLY MARGINAL AT THIS POINT
MAINLY FOR KLBB THIS EVENING...SO WE WILL NOT INCLUDE MORE THAN A
VICINITY MENTION IN THE KLBB TAF FOR NOW. RMCQUEEN
PREV DISCUSSION... /ISSUED 325 PM CDT SAT JUN 22 2013/
SHORT TERM...
THE PRIMARY FOCUS REMAINS ON CONVECTIVE CHANCES LATE THIS AFTERNOON
INTO THE EVENING AND AGAIN ON STORM CHANCES LATE TOMORROW
AFTERNOON...INCLUDING THE PROSPECTS FOR SEVERE WEATHER. LARGE SCALE
PATTERN WILL NOT CHANGE MUCH LOCALLY AS THE REGION REMAINS ON THE
SOUTHERN FRINGE OF SOUTHWESTERLY FLOW ALOFT. ONE PRONOUNCED
SHORTWAVE TROUGH WILL LIFT ACROSS THE NORTHERN HIGH PLAINS TONIGHT
WHILE WATER VAPOR IMAGERY DOES SHOW INCREASING SUPPORT/MOISTENING
APPROACHING THROUGH NM AND AZ. WEAK SUPPORT ALOFT COUPLED WITH A
DRYLINE CURRENTLY TIGHTENING ACROSS THE FAR WESTERN ZONES SHOULD BE
ENOUGH TO TRIGGER SCATTERED CONVECTION BY LATE THIS AFTERNOON OR
EARLY THIS EVENING. STRONG INSTABILITY ALONG AND ESPECIALLY JUST
EAST OF THE DRYLINE AND IMPROVING 0-6 KM SHEAR WILL SUPPORT A SEVERE
WEATHER RISK INTO THIS EVENING...INCLUDING DAMAGING WINDS AND LARGE
HAIL. IN ADDITION...STORM MOTIONS WILL BE FAIRLY SLOW...PARTICULARLY
IF ANY MID-LEVEL CYCLONIC ROTATION CAN BE ACQUIRED /WHICH WILL BE
POSSIBLE/ AND GIVEN ABOVE AVERAGE PWATS IN PLACE...A LOCALIZED HEAVY
RAIN THREAT WILL EXIST. IN GENERAL...THIS ACTIVITY WILL ADVANCE
EASTWARD BUT WILL LIKELY HAVE DIFFICULTY MOVING TOO FAR OFF INTO THE
ROLLING PLAINS GIVEN THE STRONGER INHIBITION PROGGED THERE.
CONVECTION WILL WANE LATE TONIGHT BUT A SIMILAR SETUP WILL REDEVELOP
ON SUNDAY SETTING THE STAGE FOR ANOTHER CHANCE OF STORMS...PRIMARILY
ON THE CAPROCK. LATEST GUIDANCE DOES SUGGEST MOISTURE...INSTABILITY
AND SHEAR WILL BE LOWER THAN TODAY SO THIS MAY MODULATE STORM
COVERAGE AND INTENSITY SUNDAY AFTERNOON. OTHERWISE...MILD CONDITIONS
WILL CONTINUE WITH LOWS TONIGHT RANGING FROM THE MID 60S NORTHWEST
TO MID 70S SOUTHEAST AND AFTERNOON HIGHS ON SUNDAY WELL INTO THE
90S.
LONG TERM...
NO SIGNIFICANT CHANGES TO THE FCST THIS AFTN. STILL APPEARS THAT
MONDAY WILL BE THE LAST DAY TO SEE THUNDERSTORMS IN THE LOW LEVEL
MOISTURE AXIS UNDERNEATH SWLY MID TO UPPER LEVEL FLOW BEFORE UPPER
RIDGING BUILDS OVER THE ROCKIES. THAT RIDGE SHOULD SHUT
EFFECTIVELY SHUT OFF PRECIP CHANCES FOR TUESDAY THROUGH THURSDAY
AND INCREASED HEIGHTS AND THICKNESSES CONTINUE TO SUGGEST WARMER
TEMPERATURES...BUT STAYING AWAY FROM EXTREME HEAT WITH THE HEIGHT
AND THERMAL RIDGES CENTERED OVER COLORADO AND NORTHERN NEW MEXICO.
STILL A SIGNAL IN THE MEDIUM RANGE OF PRECIP WORKING INTO THE FCST
AREA FRIDAY AND/OR SATURDAY AS THE UPPER RIDGE SHIFTS WWD TOWARD
UTAH AND ARIZONA ALLOWING DEEPER NORTHERLY FLOW TO DEVELOP ACROSS
THE PLAINS AND THUS THE POSSIBILITY OF A COLD FRONT AND UPPER
DISTURBANCES TO ADVANCE TOWARD THE AREA. WILL NUDGE POPS TOWARD
SLIGHT CHANCE BUT KEEP THEM JUST BELOW MENTION WAITING TO SEE IF
FUTURE RUNS CONTINUE TO ADVERTISE THIS PATTERN.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 64 94 66 93 66 / 10 20 20 20 20
TULIA 66 93 67 94 67 / 10 20 20 20 20
PLAINVIEW 68 92 67 93 69 / 10 20 20 20 20
LEVELLAND 65 94 68 92 69 / 10 20 20 20 20
LUBBOCK 70 94 69 94 71 / 10 20 20 20 20
DENVER CITY 66 97 69 94 69 / 20 20 20 20 20
BROWNFIELD 65 95 68 92 69 / 20 20 20 20 20
CHILDRESS 72 96 70 96 71 / 10 10 10 10 10
SPUR 70 93 70 94 71 / 10 10 10 10 10
ASPERMONT 75 96 71 97 73 / 10 10 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/99/05
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
346 AM CDT SUN JUN 23 2013
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 346 AM CDT SUN JUN 23 2013
MAIN FORECAST CONCERNS THIS PACKAGE...SHRA/TSRA/HEAVY RAINS/SEVERE
THREAT THROUGH THE PERIOD...TEMPERATURES.
DATA ANALYSIS AT 06Z HAD LOW PRESSURE OVER EASTERN CO/WESTERN KS
WITH A TROUGH NORTHEAST TO NEAR THE DAKOTAS/MN BORDER. A COUPLE OF
BOUNDARIES/WEAKER TROUGHS EXTENDED EAST-WEST ACROSS NORTHERN IA AND
WI/IL BORDER AND FROM NEAR KFSD TO NORTHWEST WI. THESE LAST TWO
LIKELY ARTIFACTS OF BOTH ONGOING CONVECTION AND THAT FROM LAST
NIGHT. LOW LEVEL JET/MOISTURE TRANSPORT/THETA-E CONVERGENCE
IMPINGING ON THE NORTHERN IA BOUNDARY PRODUCING ANOTHER ROUND OF
HEAVY RAIN PRODUCING TSRA ACROSS EASTERN SD TO SOUTHERN WI.
DANGEROUS FLASH FLOODING OCCURRING OVER FAR NORTHEAST IA AND FAR
SOUTHWEST WI WHERE HEAVY RAINS HAVE FALLEN FOR THE SECOND STRAIGHT
NIGHT.
NO LARGE...GLARING ERRORS NOTED WITH 23.00Z MODEL INITIALIZATIONS...
THOUGH PLENTY OF SMALLER/MESO-SCALE DIFFERENCES IN THE 850-500MB
FIELDS. MUCH MORE THAN ONE WOULD LIKE TO SEE WHEN THE FCST AND
SENSIBLE WEATHER OUTCOMES ARE KEYED TO THE SMALL SCALE FEATURES.
DPROG/DT OF 500MB HGTS AT 23.00Z SHOWED THE MODEL RUNS OF 21.00Z
AND 22.00Z VERIFIED WELL ACROSS NOAM/EASTERN PAC...AT LEAST WITH
THE LARGER SCALE FEATURES. ALL EARLIER RUNS LOOKED TOO WEAK WITH
THE SHORTWAVE FEATURES IN THE SOUTHWEST FLOW FROM MN/WI TO TX/CO.
EVEN WITH SOME DIFFERENCES AT THE START...AT LEAST AT 500MB MODELS
QUITE SIMILAR FOR TODAY/TONIGHT AS THE TROUGH EXITING THE NORTHERN
ROCKIES LIFTS NORTHEAST INTO MAN/WESTERN ONT. SOME DIFFERENCES WITH
THE TROUGH/LOW AT 12Z MON ONCE IT IS IN MAN/ONT BUT THIS WELL NORTH
OF THE FCST AREA. MODELS SURPRISINGLY SIMILAR WITH A SMALL SOUTHWEST
FLOW SHORTWAVE TO BE APPROACHING/CROSSING THE AREA MONDAY. CHECK OF
OBS VS. MODEL DATA AT 06Z SHOWED MOST WERE A BIT WEAK WITH A WAVE
OF LOW PRESSURE OVER NORTHEAST NEB AND THE BOUNDARY ACROSS NORTHERN
IA. MOST WERE STRUGGLING A BIT WITH SFC DEW POINTS IN THE MOISTURE
PLUME OVER THE MID/UPPER MS VALLEY. PER WV IMAGERY AND REGIONAL
RADAR REFLECTIVITY...ECMWF LOOKED A LITTLE BETTER WITH THE
SHORTWAVE DETAILS ACROSS THE CENTRAL CONUS. MODELS AGAIN GENERALLY
STRUGGLING WITH THE 00-06Z PRECIP ACROSS THE REGION. SOME BETTER IN
AREAS THAN OTHERS BUT OVERALL NO ONE MODEL LOOKED BETTER THAN THE
OTHERS. FAVORED A MODEL/ENSEMBLE CONSENSUS HEADED BY THE LOCAL
REGIONAL WRF MODELS...WHICH WERE BETTER AT DEPICTING THE CONVECTION
ACROSS THE AREA THRU THE EVENING HOURS. WITH THE MESO-SCALE DETAIL
DIFFERENCES...SHORT-TERM FCST CONFIDENCE NEAR TO BELOW AVERAGE THIS
CYCLE.
PER THE MODEL CONSENSUS...FORCING FOR CONVECTION OVER THE AREA EARLY
THIS MORNING LOOKS TO WANE AS THE SD SHORTWAVE LIFTS INTO MN. THIS
INCREASES THE MID LEVEL FLOW AND TAKES MORE OF THE MOISTURE TRANSPORT
WITH IT...PASSING NORTHWEST OF THE FCST AREA. ANY BREAK FROM THE
CONVECTION THEN LOOKS TO BE SHORT LIVED. AS THE MAIN SHORTWAVE LIFTS
ACROSS THE DAKOTAS TODAY IT PUSHES THE SFC-700MB TROUGH BACK TO THE
EAST/SOUTH ALONG WITH THE LOW LEVEL JET/MOISTURE TRANSPORT/THETA-E
CONVERGENCE. AS THIS TROUGHING APPROACHES SHRA/TSRA EXPECTED TO
DEVELOP ALONG IT THEN MOVE ACROSS THE FCST AREA DURING THE LATE
AFTERNOON/EVENING HOURS. PW VALUES REMAIN IN THE 1.5 TO 2 INCH
RANGE AND WARM CLOUD DEPTH OF 3.5 TO 4KM...ANY TSRA WILL ONCE AGAIN
BE EFFICIENT RAIN PRODUCERS WITH THE THREAT OF MORE HEAVY RAINS
ACROSS THE FCST AREA. GIVEN THE PAST 2 NIGHTS OF HEAVY RAINS AND NO
ROOM TO PUT ANY MORE WATER...WILL ISSUE A FLASH FLOOD WATCH FOR ALL
BUT CLARK/TAYLOR COUNTIES FROM 3 PM THIS AFTERNOON TO 7 AM MON
MORNING. TRENDED RAIN CHANCES TOWARD 70 PERCENT WITH THE APPROACH/
PASSAGE OF THE SFC/LOW LEVEL TROUGH THIS AFTERNOON/EVENING.
ML CAPES IN THE 2K-3K RANGE THIS AFTERNOON HOWEVER MOST OF THE SHEAR
IS IN THE 0-3KM LAYER AT 15-30KTS. THIS WITH THE APPROACHING
TROUGH/FRONT...FAVORABLE FORCING AND LOWER LEVEL WIND SHEAR FOR
LINEAR CONVECTIVE SYSTEMS AND BOWING SEGMENTS FOR A DAMAGING WIND
THREAT WITH MORE ORGANIZED TSRA. SEE SWODY1 FOR MORE DETAILS.
APPEARS TO BE ANOTHER BREAK LATER TONIGHT/MON MORNING WITH THE MAIN
FORCING/LIFT AND MOISTURE TRANSPORT PUSHED EAST/SOUTH OF THE AREA...
BUT NOT BY FAR. IF MODEL CONSENSUS IS CORRECT WITH ANOTHER
SOUTHWEST FLOW SHORTWAVE TO MOVE INTO THE REGION MON...LOW LEVEL
JET/MOISTURE TRANSPORT/THETA-E CONVERGENCE ARE AGAIN POINTED AT THE
FCST AREA FOR MON AFTERNOON/EVENING. THIS WITH ML CAPES OF 2K TO 4K
J/KG AND PW VALUES OF 1.5 TO 2 INCHES IN THE INFLOW AIRMASS. RAISED
SHRA/TSRA CHANCES FOR MON AFTERNOON BUT MORE OF THIS MAY BE INTO
MONDAY EVENING/NIGHT. THE WAY THINGS HAVE BEEN GOING...ITS LIKELY
ANOTHER FLASH FLOOD WATCH WILL BE NEEDED FOR MON NIGHT.
USED A MODEL/ENSEMBLE CONSENSUS FOR HIGHS/LOWS TODAY THRU MON.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 346 AM CDT SUN JUN 23 2013
MODEL CONSENSUS TREND FOR MON NIGHT THRU TUE NIGHT IS STRONGER WITH
ANOTHER SHORTWAVE TROUGH TO COME OUT OF THE ROCKIES MON NIGHT AND
END UP OVER THE UPPER MIDWEST BY WED MORNING. HOWEVER RUN-TO-RUN
CONSISTENCY ON THIS FEATURE NOT THAT GOOD. FCST CONFIDENCE IN THIS
PERIOD AVERAGE.
MON NIGHT THRU TUE NIGHT LOOKS LIKE A CONTINUATION OF THE UNSETTLED/
WET STRETCH OF DAYS. THE VERY MOIST AND UNSTABLE AIRMASS WILL
REMAIN IN PLACE OVER THE REGION THRU TUE NIGHT. THIS AS MORE
SHORTWAVE ENERGY RIPPLES THRU THE FLOW AND ACROSS THE REGION AND
ONE OR MORE FRONTAL BOUNDARY NEAR OR MOVING ACROSS THE FCST AREA.
COMPLEX OF SHRA/TSRA INITIATED MON AFTERNOON EXPECTED TO BE MOVING
ACROSS THE REGION MON NIGHT. AFTER THIS ONE CLEARS THE AREA/
DIMINISHES TUE MORNING...ATMOSPHERE LOOKS TO QUICKLY RELOAD. WITH THE
APPROACH OF ANOTHER SHORTWAVE AND AN INCREASING LOW LEVEL JET AND
MOISTURE TRANSPORT TOWARD THE AREA...YET ANOTHER CONVECTIVE COMPLEX
WITH THE THREAT OF MORE HEAVY RAINS LOOKS TO DEVELOP MOVE ACROSS
SOME PORTION OF IA/MN/WI. DIFFERENCES IN THE DETAILS BY TUE/TUE
NIGHT SO PLENTY OF UNCERTAINTY ON WHERE THE GREATEST HEAVY RAIN
THREAT WOULD BE. DUE TO THE CONVECTION UNKNOWNS...FOR NOW USED THE
MODEL/ENSEMBLE CONSENSUS OF LOWS/HIGHS MON NIGHT THRU TUE NIGHT.
MEDIUM RANGE MODEL RUNS OF 23.00Z CONTINUE TO SHOW A PATTERN
TRANSITION IN THE WED-SAT PERIOD. INCREASING SIGNAL FOR RIDGING TO
BUILD OVER THE WESTERN CONUS WITH DOWNSTREAM NORTHWEST FLOW
DEVELOPING OVER THE UPPER MIDWEST. GIVEN DECENT BETWEEN MODEL AND
RUN-TO-RUN CONSISTENCY...FCST CONFIDENCE IN THE DAY 4-7 PERIOD
AVERAGE TO GOOD THIS CYCLE.
WED-SAT TRENDING TO BE A DRIER/COOLER PERIOD AS THE FLOW TRANSITIONS
TO THE NORTHWEST. APPEARS TUE NIGHT/WED MORNING MAY BE THE LAST OF
THE CONVECTIVE COMPLEX/HEAVY RAIN THREATS. FLOW BECOMES BRIEFLY
WESTERLY/ZONAL WED WITH THE MID LEVEL TROUGH AND SFC LOW MOVING EAST
OF THE REGION. THIS CHANGE PUSHES THE VERY MOIST AIRMASS OUT OF THE
AREA. SHRA/TSRA STILL POSSIBLE WED INTO THU NIGHT WITH PASSAGE OF
THE SFC LOW WED THEN WEAK NORTHWEST FLOW SHORTWAVES WED NIGHT INTO
SAT. ANY OF THESE SHRA/TSRA THESE WOULD BE MUCH MORE SCATTERED IN
COVERAGE /ESPECIALLY BY THU/...HAVE LESS MOISTURE/INSTABILITY
TO WORK WITH AND BE MORE DIURNALLY DRIVEN. SMALLER MODEL CONSENSUS
SHRA/TSRA CHANCES FOR MUCH OF THE WED-SAT PERIOD LOOK REASONABLE
AT THIS TIME. MODEL/ENSEMBLE CONSENSUS HIGHS/LOWS FOR THIS PERIOD
LOOK GOOD AS WELL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1237 AM CDT SUN JUN 23 2013
BOUNDARY ACROSS NORTHEAST IOWA INTO SOUTHWEST WISCONSIN HAS SHOWN
NO MOVEMENT THROUGH THE EVENING HOURS WITH STORMS CONTINUING ALONG
AND NORTH OF IT. REGIONAL AND LOCAL RADAR DOES SHOW A BREAK IN THE
ACTIVITY BACK IN THE INTERSTATE 35 CORRIDOR. THE NEXT ROUND OF
CONVECTION OVER SOUTHWEST MINNESOTA INTO SOUTH DAKOTA HAS A MORE
NORTHEAST MOVEMENT. THE LAST TWO RUNS OF THE LOCAL ARX-LAPS HAS
LATCHED ONTO THESE DIFFERENT AREAS OF CONVECTION WITH THE 23.03Z
RUN TAKING THE ACTIVITY OVER THE AREA OFF TO THE EAST AND OUT OF
THE REGION DURING THE OVERNIGHT WHILE TAKING THE NEXT ROUND PAST
THE AREA TO THE NORTH. THE 23.03Z HRRR SHOWS THE SAME TRENDS SO
PLAN TO CONTINUE THE TSRA THROUGH 08Z AT KRST AND 10Z AT KLSE.
AFTER THAT WILL JUST DROP BACK TO VCSH FOR A SHORT WHILE BEFORE
GOING TOTALLY DRY FOR THE REMAINDER OF THE MORNING. MVFR
CONDITIONS WILL BE POSSIBLE WITH ANY OF THE TSRA ACTIVITY UNTIL IT
ENDS. BY MID TO LATE AFTERNOON...THE 23.00Z NAM INDICATES THE
SYNOPTIC BOUNDARY SHOULD PUSH INTO THE AREA WITH A SHORT WAVE
TROUGH AND AS THE UPPER LEVEL FLOW TRIES TO TURN A LITTLE MORE TO
THE WEST. SHOULD SEE MORE CONVECTION DEVELOP ALONG THIS BOUNDARY
AND HAVE PUT IN A VCTS TO SHOW THIS WITH THE EXPECTATION THAT
LATER FORECASTS WILL DETAIL THE TIMING BETTER.
&&
.HYDROLOGY...
ISSUED AT 346 AM CDT SUN JUN 23 2013
FLOODING AND FLASH FLOODING ONGOING ACROSS PORTIONS OF THE FCST
AREA THIS MORNING...ALONG THE MN/IA BORDER INTO FAR SOUTHWEST
WI. THIS BEING COVERED BY FLASH FLOOD AND AREAL FLOOD WARNINGS.
DUE TO THE RECENT RAINS OF THE PAST FEW DAYS...SATURATED SOILS AND
THE THREAT FOR ANOTHER ROUND OF 1/2 TO 1 INCH OF RAIN...LOCALLY 2
INCHES OR MORE IN REPEATING TSRA LATER THIS AFTERNOON AND TONIGHT
WITH THE APPROACH OF THE SFC THRU MID LEVEL TROUGH...WILL ISSUE A
FLASH FLOOD WATCH FROM 3 PM THIS AFTERNOON TO 7 AM MONDAY.
TRIBUTARY RIVERS LIKE THE KICAKPOO...BLACK...UPPER IOWA AND TURKEY
RIVERS CONTINUE TO RISE AND REACH FLOOD STAGE AS WELL. ADDITIONAL
HEAVY RAINS AND HIGH RUNOFF PERCENTAGES WILL ONLY CREATE MORE
PROBLEMS WITH THESE LARGER RIVERS...ESPECIALLY AS THIS PERIOD OF
STORMY WEATHER AND THREAT OF MORE ROUNDS OF HEAVY RAINS CONTINUES.
IN ADDITION TO THE SHORT TERM WATER CONCERNS...THERE IS A RIVER
FLOOD WATCH FOR THE MISSISSIPPI AT WABASHA...WINONA...AND LA CROSSE.
WATER FROM THE TRIBUTARY RIVERS...AND RIVERS NORTH OF THE FCST AREA
WILL EVENTUALLY MAKE ITS WAY INTO THE MS RIVER...WITH THE MS RIVER
AT THESE LOCATIONS EXPECTED TO RISE ABOVE FLOOD STAGE AROUND OR
AFTER THE 1ST OF JULY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FLASH FLOOD WATCH FROM 3 PM CDT THIS AFTERNOON THROUGH MONDAY
MORNING FOR WIZ032>034-041>044-053>055-061.
MN...FLASH FLOOD WATCH FROM 3 PM CDT THIS AFTERNOON THROUGH MONDAY
MORNING FOR MNZ079-086>088-094>096.
IA...FLASH FLOOD WATCH FROM 3 PM CDT THIS AFTERNOON THROUGH MONDAY
MORNING FOR IAZ008>011-018-019-029-030.
&&
$$
SHORT TERM...RRS
LONG TERM....RRS
AVIATION.....04
HYDROLOGY....RRS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1238 AM CDT SUN JUN 23 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 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1237 AM CDT SUN JUN 23 2013
BOUNDARY ACROSS NORTHEAST IOWA INTO SOUTHWEST WISCONSIN HAS SHOWN
NO MOVEMENT THROUGH THE EVENING HOURS WITH STORMS CONTINUING ALONG
AND NORTH OF IT. REGIONAL AND LOCAL RADAR DOES SHOW A BREAK IN THE
ACTIVITY BACK IN THE INTERSTATE 35 CORRIDOR. THE NEXT ROUND OF
CONVECTION OVER SOUTHWEST MINNESOTA INTO SOUTH DAKOTA HAS A MORE
NORTHEAST MOVEMENT. THE LAST TWO RUNS OF THE LOCAL ARXLAPS HAS
LATCHED ONTO THESE DIFFERENT AREAS OF CONVECTION WITH THE 23.03Z
RUN TAKING THE ACTIVITY OVER THE AREA OFF TO THE EAST AND OUT OF
THE REGION DURING THE OVERNIGHT WHILE TAKING THE NEXT ROUND PAST
THE AREA TO THE NORTH. THE 23.03Z HRRR SHOWS THE SAME TRENDS SO
PLAN TO CONTINUE THE TSRA THROUGH 08Z AT KRST AND 10Z AT KLSE.
AFTER THAT WILL JUST DROP BACK TO VCSH FOR A SHORT WHILE BEFORE
GOING TOTALLY DRY FOR THE REMAINDER OF THE MORNING. MVFR
CONDITIONS WILL BE POSSIBLE WITH ANY OF THE TSRA ACTIVITY UNTIL IT
ENDS. BY MID TO LATE AFTERNOON...THE 23.00Z NAM INDICATES THE
SYNOPTIC BOUNDARY SHOULD PUSH INTO THE AREA WITH A SHORT WAVE
TROUGH AND AS THE UPPER LEVEL FLOW TRIES TO TURN A LITTLE MORE TO
THE WEST. SHOULD SEE MORE CONVECTION DEVELOP ALONG THIS BOUNDARY
AND HAVE PUT IN A VCTS TO SHOW THIS WITH THE EXPECTATION THAT
LATER FORECASTS WILL DETAIL THE TIMING BETTER.
&&
.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...04
HYDROLOGY...BOYNE
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1053 PM MDT SAT JUN 22 2013
.UPDATE...
ISSUED AT 938 PM MDT SAT JUN 22 2013
SHOWERS AND TSTMS ARE REALLY BEGINNING TO WIND DOWN AS THE STRONG
SHORTWAVE PASSES ACROSS THE CWA AND THE SUBSIDENCE FOLLOWS. KEPT
SCATTERED SHOWERS IN THE NEBRASKA PANHANDLE THROUGH MIDNIGHT THEN
REMOVED ANY MENTION OF PRECIP. SHOULD BE A QUIET NIGHT AS A WEAK
FRONTAL PASSAGE SWITCHES WINDS TO THE NORTH. THE NAM SUGGESTS LOW
CLOUDS WILL BE POSSIBLE OVER THE PLAINS LATER TONIGHT WHEREAS THE
GFS IS DRIER IN THE LLVLS. WILL KEEP LOW CLOUDS OUT OF THE GRIDS
FOR NOW WITH THE HRRR ONLY SHOWING IFR CIGS ALONG THE SOUTHERN
LARAMIE RANGE EASTWARD INTO LARAMIE COUNTY.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 417 PM MDT SAT JUN 22 2013
THE CLUSTER OF THUNDERSTORMS MOVING THROUGH AREAS EAST OF THE
LARAMIE RANGE WILL CONTINUE TO SHIFT EAST DURING THE COURSE OF THE
EVENING. 0-1KM STORM RELATIVE HELICITY VALUES ARE RANGING FROM
50-100M^2/S^2 IN GOSHEN AND ALBANY COUNTIES. FURTHER EAST OF THIS
LCLS ARE A BIT LOWER WITH VALUES RANGING FROM 500M- 1000M.
THEREFORE...CONTINUED TORNADO THREAT LOOKS TO BE FAIRLY MARGINAL
THIS EVENING...BUT STILL CANNOT RULE SOME BRIEF TOUCHDOWNS AS THE
LINE CONTINUES TO PUSH EAST. MEANWHILE...LARGE HAIL AND DAMAGING
WIND THREAT STILL LOOKS FAVORABLE AT THIS TIME. ALL OF THIS
ACTIVITY CONTINUES TO DEVELOP AHEAD OF THE MAIN SHORTWAVE PIVOTING
THROUGH CENTRAL WYOMING. THIS SHORTWAVE WILL CONTINUE TO SHIFT
EAST THIS EVENING AND BRING DRIER AIR INTO THIS EVENING. WE WILL
BE CLEARING THE TORNADO WATCH IN CONVERSE AND ALBANY COUNTIES
SHORTLY.
TONIGHT AND SUNDAY:
CLEARING SKIES ARE EXPECTED LATE THIS EVENING AND OVERNIGHT AS THE
SUBSIDENCE BUILDS IN WITH THE PASSING SHORTWAVE. IT MAY BE QUITE
COOL IN A FEW LOCATIONS WITH 40S IN WYOMING AND 50S IN THE
NEBRASKA PANHANDLE. LEE SIDE TROF DOES TRY TO SET UP CAMP...BUT
NOT REAL CONFIDENT THAT SHOWERS AND STORMS WILL DEVELOP. FOR
NOW...WE WILL CONSISTENCY SAKE WE WILL KEEP THE CHANCE OF SHOWERS
AND THUNDERSTORMS IN THE PICTURE.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 417 PM MDT SAT JUN 22 2013
NOT MANY CHANGES MADE TO THE LONG TERM DUE TO WIDESPREAD SEVERE
WEATHER THIS AFTERNOON. WE WILL NEED TO WATCH FOR A POTENTIAL
SHORTWAVE MOVING THROUGH THE NORTHERN PARTS OF THE FORECAST AREA
MONDAY NIGHT AND TUESDAY WHICH MAY BRING A CHANCE OF SHOWERS OF
THUNDERSTORMS. OTHERWISE...THE UPPER LEVEL RIDGE WILL CONTINUE TO
BUILD OVER THE REGION LATER IN THE WEEK AND BRING WARMER
TEMPERATURES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY EVENING)
ISSUED AT 1053 PM MDT SAT JUN 22 2013
THUNDERSTORM ACTIVITY HAS SLID EAST OF AREA TERMINALS LATE THIS
EVENING...GIVING WAY TO DRIER CONDITIONS DURING THE MORNING HOURS. A
WEAK FRONT WILL SURGE SOUTH POTENTIALLY PRODUCING TO MVFR CIGS FOR A
TIME AT KCYS...KCDR AND KAIA BETWEEN 08Z-13Z. OTHERWISE...ANTICIPATE
VFR CONDITIONS TO PREVAIL THROUGH THE MORNING. ANOTHER ROUND OF
-TSRA ARE EXPECTED FOR KCYS...KBFF AND KSNY ON SUNDAY AFTERNOON...SO
HAVE ADDED VCTS MENTION TO THOSE AIRFIELDS AFTER 18Z.
&&
.FIRE WEATHER...
ISSUED AT 417 PM MDT SAT JUN 22 2013
LOW RELATIVE HUMIDITIES WILL BE IN STORE FOR AREAS MAINLY WEST OF
THE LARAMIE RANGE SUNDAY AFTERNOON. OTHERWISE...THE LEE SIDE TROF
IS EXPECTED TO DEVELOP OVER THE AREA ON MONDAY WITH GUSTY AND DRY
SOUTHWEST FLOW POSSIBLE WEST OF THE LARAMIE RANGE ON MONDAY WHICH
WILL FAVOR INCREASED FIRE RISK.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...FINCH
SHORT TERM...REC
LONG TERM...SLA
AVIATION...CH
FIRE WEATHER...REC
AREA FORECAST DISCUSSION
NWS ALBANY NY
1026 AM EDT SUN JUN 23 2013
.SYNOPSIS...
A WARM AND HUMID AIR MASS WILL CONTINUE THIS AFTERNOON THROUGH
THE MIDDLE OF NEXT WEEK. ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS WILL BE POSSIBLE IN THE AFTERNOON AND EARLY EVENING
THE NEXT FEW DAYS. SOME LOCALLY HEAVY RAINFALL WILL BE
POSSIBLE...AND PATCHY FOG WILL BE COMMON WITH MUGGY CONDITIONS
EACH NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1026 AM EDT...A DIFFUSE FRONTAL BOUNDARY CONTINUES TO BE
NORTH OF THE FORECAST AREA THIS MORNING. SOME SHOWERS AND
THUNDERSTORMS MOVED ACROSS THE SOUTHERN ADIRONDACKS EARLY THIS
MORNING...LEAVING UP TO AN INCH OF RAINFALL /ACCORDING TO RADAR
ESTIMATES/ IN SPOTS NEAR INDIAN LAKE.
THE FRONTAL BOUNDARY WILL CONTINUE TO LIFT NORTHWARD DURING THE
DAY...AS A SUBTROPICAL HIGH OFF THE MID ATLANTIC COAST AT THE
SFC...AND ALOFT CONTINUES TO FUNNEL HUMID AIR NORTHWARD. SFC
DEWPTS TODAY WILL RISE INTO THE MID AND U60S IN SOME LOCATIONS
WITH SOUTH TO SOUTHWEST SFC LAYER WINDS. H850 TEMPS INCREASE TO
+16 TO +17C WITH PARTLY TO MOSTLY SUNNY CONDITIONS. MAX TEMPS IN
THE M80S TO NEAR 90F WILL BE LIKELY IN THE VALLEYS WITH U70S TO
L80S OVER THE MTNS.
WEAK MID LEVEL VORTICES MOVING ALONG THE RIM OF THE UPPER LEVEL
RIDGE MAY TRIGGER SOME ISOLD-SCT THUNDERSTORMS TODAY. THE BEST 0-6
KM BULK SHEAR IS ACTUALLY JUST NORTH OF THE FCST AREA ACROSS NRN
NY AND NRN NEW ENGLAND WITH 20-30 KTS. MOST OF THE ALY FCST AREA
WILL BE IN A WEAK SHEAR ENVIRONMENT OF 10-20 KTS FOR PULSE OR VERY
LOOSELY ORGANIZED THUNDERSTORMS. FREEZING LEVELS WILL BE HIGH IN
THE 12-14 KFT AGL RANGE WITH WBZ HEIGHTS AROUND 11 KFT AGL.
SBCAPES WILL BE IN THE 500-1500 J/KG RANGE ACCORDING TO THE GFS.
NOT BUYING INTO THE NAM/S FAIRLY WIDESPREAD LOWER 70S DEWPT AIR OVER
THE REGION WITH SBCAPES OF 2000-3000 J/KG.
THE NEW 12Z NAM...AS WELL AS THE 12Z 3KM HRRR AND THE 12Z LOCAL
HIRES WRF SHOW CELLULAR CONVECTION POPPING UP ACROSS THE
ADIRONDACKS BY THE EARLY TO MID AFTN...AND MORE ACTIVITY
DEVELOPING AND MOVING ACROSS THE MOHAWK VALLEY...CAPITAL REGION
AND SRN VT...BY THE MID/LATE AFTN AND INTO THE EVENING HOURS. EACH
MODEL HAS THE PLACEMENT/TIMING SLIGHTLY DIFFERENT...BUT THE
CONVECTIVE MODE /CELLULAR PULSE TYPE STORMS/ SEEMS TO BE SIMILAR
IN EACH MODEL.
THIS MORNING/S 12Z KALY SOUNDING SHOWED A PWAT OF 1.62. AS A
RESULT...A MENTION OF HVY RAIN HAS BEEN INCLUDED WITH ISOLD-SCT
THUNDERSTORMS TODAY IN THE GRIDDED...TEXT FORECASTS...AND HWO
STATEMENT. AN ISOLD SEVERE MAY BE POSSIBLE TOO...ESPECIALLY IN
THE NRN ZONES...BUT THE FORECASTED WEAK MID LEVEL LAPSE RATES OF
LESS THAN 6 C/KM AND LIMITED AMOUNTS OF SHEAR IN THE 0-6 KM LAYER
SHOULD PROHIBIT WIDESPREAD STRONG CELLS. SPC MAINTAINS A /SEE
TEXT/ AREA ACROSS THE CENTRAL/NORTHERN PART OF THE CWA AND WE WILL
CONTINUE TO MONITOR MESOSCALE TRENDS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
TONIGHT...THE ISOLD TO SCT CONVECTION SHOULD SHRIVEL UP QUICKLY
BEFORE MIDNIGHT WITH THE LOSS OF THE DAYTIME HEATING. A PARTIAL
CLEARING WILL ALLOW PATCHY FOG JUST ABOUT ANYWHERE IN THE FCST
AREA WITH THE MOIST LOW LEVELS. IT HAS BEEN ADDED TO THE FORECAST
GRIDS. STICKY CONDITIONS WILL PREVAIL WITH LOWS IN THE MID AND
U60S IN THE VALLEYS...AND LOWER TO M60S OVER THE HILLS AND MTNS.
MONDAY...THE SULTRY CONDITIONS IN PLACE WILL PROMOTE INCREASED
CHANCES OF MORE PULSE THUNDERSTORMS WITH DEEP SHEAR VALUES LESS
THAN 15 KTS. SBCAPES WILL SOLIDLY BE IN THE 1000-2000 J/KG RANGE.
SOME THUNDERSTORMS MAY BE SLOW MOVERS OR LATCH TO THE TERRAIN FOR
A QUICK INCH OR TWO OF RAINFALL IN THE ANOMALOUSLY HIGH PWAT AIR
MASS. THE NAM SHOWS HINTS OF A SHORT-WAVE TROUGH IN THE W/SW ALOFT
MOVING THROUGH DURING THE AFTERNOON. THE ECMWF/GFS ALSO SHOW A
SUBTLE SHORT-WAVE TROUGH IN THE FLOW ALOFT. THE MID LEVEL LAPSE
RATES STEEPEN TO AROUND 6.5C/KM ON THE GFS. 850HPA THETA-E VALUES
INCREASE TO CLOSE TO 340K ACROSS PORTIONS CNTRL-ERN NY. THE
THETA-E RIDGE WEAKENS SLIGHTLY TOWARDS NIGHT FALL WITH THE PASSAGE
OF THIS TROUGH. HVY RAIN HAS BEEN INCLUDED WITH THE THUNDERSTORMS
AGAIN IN THE GRIDS/TEXT PRODUCTS. H850 TEMPS INCREASE CLOSE TO +17
TO +18C WITH THE GFSMOS TEMPS MUCH WARMER THAN THE METMOS TEMPS. A
BLEND WAS USED WITH A SHADING A LITTLE CLOSER TO THE GFSMOS VALUES
WITH SOUTHWEST TO WEST WINDS IN THE SFC TO BOUNDARY LAYER...TEMPS
MAY SPIKE UP A LITTLE BIT IN THE VALLEYS DUE TO DOWNSLOPING WITH
HIGHS IN THE U80S TO L90S WITH U70S TO M80S OVER THE HILLS AND
MTNS. APPARENT TEMPS COULD GET INTO M90S OR EVEN A FEW U90S IN THE
MID HUDSON VALLEY.
MONDAY NIGHT...SOME SUBSIDENCE OR DRYING ALOFT IN THE WAKE OF THE
TROUGH WILL ALLOW THE SKIES TO GO AT LEAST PARTLY
CLOUDY...ESPECIALLY THE NRN ZONES. PATCHY FOG WILL BE POSSIBLE
AGAIN WITH LOWS IN THE 60S.
TUE-TUE NIGHT...THE BROKEN RECORD FCST CONTINUES WITH DIURNAL
DRIVEN ISOLD-SCT SHOWERS AND THUNDERSTORMS AGAIN. INITIAL
CONVECTION WILL LIKELY BE FROM DIFFERENTIAL HEATING BTWN THE MTNS
AND VALLEYS...BUT POTENTIAL LAKE BREEZES OR WEAK SFC TROUGHS
UPSTREAM WILL HAVE TO BE MONITORED FOR MORE ORGANIZED CONVECTION.
STILL FAVORING THE GFS IN TERMS OF SHEAR AND INSTABILITY. SBCAPES
WILL LIKELY BE IN THE 1000-1500 J/KG RANGE WITH WEAKER MID LEVEL
LAPSE RATES COMPARED TO MONDAY. HIGHS WILL BE SIMILAR TO MON WITH
SOME L90S IN THE HUDSON RIVER VALLEY...AND WIDESPREAD 80S OVER THE
FCST AREA. MUGGY CONDITIONS WILL CONTINUE OVERNIGHT WITH MID AND
U60S IN THE VALLEYS...AND L60S OVER THE HIGH PEAKS.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
THE MODEL GUIDANCE AND ENSEMBLES ARE IN GOOD AGREEMENT WITH THE
LONGWAVE PATTERN AND CONTINUE TO INDICATE THE SUBTROPICAL RIDGE
SETTLES IN OVER THE SOUTHWESTERN UNITED STATES AND AMPLIFIES WITH
TROUGHING OVER THE GREAT LAKES REGION AND NORTHEAST INCREASING.
OVERALL THIS WILL RESULT IN THE WEATHER BECOMING MORE UNSETTLED
OVER THE NORTHEAST AS PIECES OF SHORT WAVE ENERGY MOVE THROUGH THE
TROUGH DEEPENING IT.
THE DIFFERENCES IN THE GUIDANCE LIES WITH THE TIMING OF INDIVIDUAL
SHORT WAVES AND THE MOVEMENT AND PLACEMENT OF BOUNDARIES. A WEAK
BACKDOOR FRONT IS EXPECTED TO MOVE SOUTHWARD INTO THE REGION MID
WEEK THEN RETURN BACK NORTHWARD AS A WARM FRONT LATE IN THE WEEK AS
THE TROUGH DEEPENS OVER THE REGION AND A LOW PRESSURE SYSTEM
APPROACHES. THE REGION IS EXPECTED TO BE IN THE WARM SECTOR OF THE
SYSTEM INTO THE WEEKEND WITH THE SYSTEM`S COLD FRONT EVENTUALLY
CROSSING THE REGION SATURDAY NIGHT/SUNDAY.
TEMPERATURES ARE EXPECTED TO RETURN TO MORE SEASONABLE LEVELS.
HOWEVER DEWPOINTS WILL REMAIN HIGH...IN THE 60S...MAKING FOR HUMID
CONDITIONS.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
SCATTERED STORMS CONTINUE TO MOVE ACROSS NORTHERN NEW YORK STATE IN
THE VICINITY OF A WEAK SURFACE BOUNDARY. CHANCES FOR CONVECTION WILL
INCREASE AND SPREAD SOUTHWARD ACROSS MUCH OF THE FORECAST AREA AS
ANOTHER WEAK UPPER LEVEL DISTURBANCE APPROACHES AND MOVING ACROSS
THE REGION. EXPECTING ISOLATED TO SCATTERED CONVECTION ESPECIALLY
THIS AFTERNOON INTO EARLY EVENING HOURS. HAVE ADDRESSED THIS THREAT
WITH VCSH IN TAFS EXCEPT NOT KPOU AS ACTIVITY SHOULD BE TO THEIR
NORTH. DEWPOINT TEMPERATURES WILL BE ON THE RISE TODAY WELL INTO THE
60S SO EXPECT SOME FOG TO DEVELOP TONIGHT...MAINLY MVFR AS WILL HAVE
CLOUDS ACROSS THE REGION.
SOUTH TO SOUTHWEST WINDS TODAY AT 8 TO 12 KNOTS WITH SOME GUSTS INTO
THE TEENS AT KALB AND KPSF. WINDS WILL WEAKEN DURING THE EVENING
BECOMING LIGHT AND VARIABLE FOR THE OVERNIGHT.
OUTLOOK...
MON-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...MAINLY VFR. CHC -TSRA/-SHRA.
&&
.FIRE WEATHER...
A WARM AND HUMID AIR MASS WILL CONTINUE TODAY THROUGH
THE MIDDLE OF NEXT WEEK. ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS WILL BE POSSIBLE IN THE AFTERNOON AND EARLY EVENING
THE NEXT FEW DAYS.
RH LEVELS WILL REMAIN HIGH EACH NIGHT INTO THE MIDDLE OF NEXT WEEK
FOR THE FORMATION OF DEW ACROSS EASTERN NEW YORK AND WESTERN NEW
ENGLAND. NO FIRE WEATHER CONCERNS ARE EXPECTED AT THIS TIME.
&&
.HYDROLOGY...
FLOWS CONTINUE TO RECEDE TO LATE JUNE SEASONAL LEVELS. THE NEXT 5
DAYS WILL FEATURE ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS
WHICH WILL LIKELY NOT HAVE A SIGNIFICANT IMPACT ON THE MAIN STEM
RIVERS.
SLOW MOVING THUNDERSTORMS COULD PRODUCE A QUICK INCH OR TWO OF
RAINFALL WITH HIGHER THAN NORMAL PRECIPITABLE WATER VALUES OVER
THE HYDRO SERVICE AREA. SOME POOR DRAINAGE FLOODING OF LOW LYING
AREAS...AND PONDING OF WATER ON ROADWAYS WILL BE POSSIBLE ANY DAY
INTO THURSDAY. SOME SMALL STREAMS...CREEKS...AND BROOKS MAY REACH
BANKFULL QUICKLY IN THE HEAVY RAINFALL ASSOCIATED WITH THE
THUNDERSTORMS.
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...FRUGIS/WASULA
NEAR TERM...FRUGIS/WASULA
SHORT TERM...WASULA
LONG TERM...IAA
AVIATION...IAA
FIRE WEATHER...WASULA
HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1028 AM CDT SUN JUN 23 2013
.DISCUSSION...
ISSUED 1027 AM CDT SUN JUN 23 2013
CURRENT CONVECTION OVER SOUTHEAST CWA FIRING OFF LEFTOVER
BOUNDARIES FROM YESTERDAYS STORMS AND LIFT OFF WESTERN FRINGE OF
CLOSED MID LEVEL LOW CENTERED OVER KY. THIS OCCURRING IN A VERY
HIGH 1.8 P/W AIRMASS AND WEAK WINDS ALOFT SO STORMS ARE SLOW
MOVERS AND POSE A HEAVY RAIN THREAT. HI-RES MODELS GRADUALLY PUSH
THIS AREA EAST AFFECTING MUCH OF SE IL THROUGH MID AFTERNOON.
OTHER AREA OF CONCERN IS LINE OF STORMS SHIFTING THROUGH CENTRAL
IA WHICH HAS SHOWN RECENT CLOUD TOP COOLING ON IR SAT IMAGERY. IF
THIS HOLDS TOGETHER LIKELY WOULDNT REACH WESTERN CWA UNTIL
EVENING. HOWEVER OUTFLOW PUSHING AHEAD OF THIS ALREADY INTO
EASTERN IA EVIDENT ON KDVN REFLECTIVITY IMAGERY. AWIPS DISTANCE
SPEED TOOL BRINGS THIS INTO KNOX CO NEAR NOON AND WILL NEED TO
MONITOR NEW CONVECTION POSSIBLY FIRING ALONG/BEHIND THIS AS HAS
OCCURRED IN CWA PAST TWO DAYS. AIRMASS SHOWS LITTLE CHANGE FROM
YESTERDAY WITH HIGH P/W WEAK WINDS ALOFT AND MODERATE INSTABILITY.
THEREFORE HEAVY RAIN REMAINS PRIMARY THREAT THROUGH BULK SHEAR
INCREASES TO 30 KTS THIS AFTERNOON ACROSS THE WESTERN HALF AND
WOULD GIVE SOME ORGANIZATION FOR A LOW END SVR WIND AND HAIL
THREAT. HAVE INCREASED POPS TO LIKELY OVER THE SOUTHEAST INTO
EARLY AFTERNOON...THEN HAVE CHANCE POPS OVER REMAINDER OF CWA WITH
HIGHEST CHANCES OVER THE WEST. HIGHS WILL AGAIN REACH THE LOWER
90S IN AREAS THAT SEE MORE SUN AND WITH DEWPOINTS AROUND 70 PEAK
HEAT INDICES WILL BE IN THE UPPER 90S.
25
&&
.AVIATION...
ISSUED 532 AM CDT SUN JUN 23 2013
COVERAGE OF CONVECTION THIS PERIOD AND ITS AFFECT ON CIGS/VSBYS
THE MAIN FORECAST CHALLENGE. REMNANT CONVECTIVELY INDUCED VORT
MAX OVER SOUTH CENTRAL IL THIS MORNING TRYING TO KICK OFF SOME
MORE SHOWERS AND THUNDERSTORMS OVER SE AND SRN IL...SOUTH OF OUR
TAF SITES. EXPECT THAT AREA TO FILL IN LATER THIS MORNING...POSSIBLY
AFFECT KCMI AFTR 15Z. ADDITIONAL CONVECTION WILL BE POSSIBLE ACRS
THE WEST LATER THIS AFTN AS STORMS ACRS IOWA RE-ITENSIFY JUST WEST
OF THE MISSISSIPPI RIVER AND THEN HEAD EAST. SOME OF THE MODELS
TRY TO CURE THOSE STORMS MORE TO THE SE WHILE OPERATIONAL MODELS
SUGGEST MORE OF AN EASTWARD TRACK WHICH WOULD INCLUDE ALL OF OUR
SITES LATE THIS AFTN AND EARLY THIS EVENING. WILL STILL INCLUDE
VCTS DURING THE TIME FRAME WE THINK THE STORMS WILL BE MOVING
THRU...AND THEN ONCE CONFIDENCE INCREASES WITH RESPECT TO TIMING
AND COVERAGE...WE WOULD THEN BE ABLE TO PIN DOWN A TIME FRAME FOR
A TEMPO GROUP.
AWAY FROM THE SHOWERS AND TSRA...WE CAN EXPECT VFR CONDITIONS...BUT
ANY TAF AREA THAT SEES THE PRECIP MAY EXPERIENCE SOME BRIEF MVFR AND
LOCALLY IFR CIGS AND VSBYS IN SOME OF THE HEAVIER PRECIP. SFC WINDS
WILL REMAIN OUT OF THE SOUTH TODAY WITH SPEEDS OF 10 TO 15 KTS WITH
OCCASIONAL GUSTS UP TO 20 KTS BEFORE WINDS DIMINISH TO AROUND 10 KTS
THIS EVENING.
SMITH
&&
.PREV DISCUSSION...
ISSUED 230 AM CDT SUN JUN 23 2013
SHORT TERM...TODAY THROUGH TUESDAY...
PROBLEMATIC FORECAST CONTINUES FOR THE NEXT FEW DAYS IN REGARDS TO
CONVECTIVE DEVELOPMENT. EVENTS OF THE LAST COUPLE DAYS HAVE SHOWN
HOW LEFTOVER BOUNDARIES LEAD TO REDEVELOPMENT IN THE HEAT OF THE
DAY...AND ANOTHER SUCH BOUNDARY IS DROPPING SOUTHWARD THROUGH
FAR NORTHERN ILLINOIS...FORMED BY A DECAYING MCS OVER WISCONSIN
AND SOUTHEAST MINNESOTA. SOME WEAK BOUNDARIES ALSO DETECTED OVER
SOUTHEAST ILLINOIS LOOPING WESTWARD INTO AREAS SOUTHWEST OF SAINT
LOUIS. STORMS THAT FORM TODAY SHOULD BE VERY EFFICIENT RAIN MAKERS
AGAIN...AS PRECIPITABLE WATER VALUES WILL BE AROUND 1.7 INCHES AND
700 MB WINDS OF LESS THAN 10 KNOTS INDICATE THE STORMS WILL BE IN
NO HURRY TO MOVE ONCE THEY FORM. LATEST RAP AND HRRR MODELS SHOW
SOME DEVELOPMENT TAKING PLACE AS EARLY AS SUNRISE NEAR THE
SOUTHERN OUTFLOW...AND AFTERNOON DEVELOPMENT SHOULD ACCOMPANY THE
NORTHERN BOUNDARY. HAVE GONE A LITTLE MORE AGGRESSIVE WITH THE
POPS AS A RESULT WITH 30-40 PERCENT MOST AREAS TODAY.
OVERNIGHT PROBLEM THEN SHIFTS TO TRACK OF THE NEXT MCS WHICH
SHOULD FORM OVER IOWA THIS EVENING. NAM AND GFS ARE MORE
PROGRESSIVE WITH SPREADING IT OVER MUCH OF ILLINOIS BY EARLY
MONDAY MORNING...WHILE THE LATEST ECMWF IS SLOWER AND SHUNTS MOST
OF IT OFF TO OUR NORTH. LEANING TOWARD A MORE SOUTHERN SOLUTION AT
THE MOMENT WITH 40-50 PERCENT POPS FROM ABOUT I-55 NORTHWEST...
WITH MAINLY SLIGHT CHANCES ACROSS THE SOUTHEAST. ONCE THIS
PARTICULAR MCS EXITS ON MONDAY...THE STORM TRACK FOR THE NEXT
ROUND SHIFTS A BIT FURTHER NORTH AS SOME UPPER RIDGING BUILDS INTO
THE MID-MISSISSIPPI VALLEY.
TEMPERATURE-WISE...STILL LOOKING LIKE 90 DEGREES OR A BIT HIGHER
IS LIKELY THE NEXT FEW DAYS...PROVIDED THE STORMS DO NOT GET OUT
OF CONTROL. SLOW BUILD OF THE DEW POINTS TOWARD THE MID 70S WILL
RESULT IN HEAT INDEX VALUES A FEW DEGREES HIGHER EACH DAY...WITH
MOST AREAS JUST ABOVE 100 FOR HEAT INDEX BY TUESDAY AFTERNOON.
LONG TERM...WEDNESDAY THROUGH SATURDAY...
SUMMER-TIME PATTERN TO CONTINUE THROUGH MID WEEK. MAIN STORM TRACK
WILL BE ACROSS THE NORTH CENTRAL STATES...WITH SOME POTENTIAL FOR
SHOWERS/STORMS FURTHER SOUTH AS THE OUTFLOWS FROM THE NIGHTLY MCS
SYSTEMS DROP INTO OUR AREA. BEST CHANCE OF RAIN WILL PROBABLY BE
WEDNESDAY NIGHT...AS A SHORTWAVE DROPS INTO THE MIDWEST ALONG WITH
AN ASSOCIATED SURFACE BOUNDARY.
AS THE END OF THE WEEK PROGRESSES...UPPER LEVEL RIDGING WILL BUILD
ACROSS THE ROCKIES...WITH A NORTHWEST FLOW BRINGING COOLER
CONDITIONS TO THE MIDWEST FOR FRIDAY AND ESPECIALLY THE WEEKEND.
THINK MOST OF THE RAIN THREAT WILL BE OUT OF THE AREA BY THURSDAY
EVENING...BUT WEAK TROUGHS ROTATING THROUGH THE MIDWEST MAY
COMPLICATE THIS THINKING.
GEELHART
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
538 AM CDT SUN JUN 23 2013
.DISCUSSION...
ISSUED 230 AM CDT SUN JUN 23 2013
SHORT TERM...TODAY THROUGH TUESDAY...
PROBLEMATIC FORECAST CONTINUES FOR THE NEXT FEW DAYS IN REGARDS TO
CONVECTIVE DEVELOPMENT. EVENTS OF THE LAST COUPLE DAYS HAVE SHOWN
HOW LEFTOVER BOUNDARIES LEAD TO REDEVELOPMENT IN THE HEAT OF THE
DAY...AND ANOTHER SUCH BOUNDARY IS DROPPING SOUTHWARD THROUGH
FAR NORTHERN ILLINOIS...FORMED BY A DECAYING MCS OVER WISCONSIN
AND SOUTHEAST MINNESOTA. SOME WEAK BOUNDARIES ALSO DETECTED OVER
SOUTHEAST ILLINOIS LOOPING WESTWARD INTO AREAS SOUTHWEST OF SAINT
LOUIS. STORMS THAT FORM TODAY SHOULD BE VERY EFFICIENT RAIN MAKERS
AGAIN...AS PRECIPITABLE WATER VALUES WILL BE AROUND 1.7 INCHES AND
700 MB WINDS OF LESS THAN 10 KNOTS INDICATE THE STORMS WILL BE IN
NO HURRY TO MOVE ONCE THEY FORM. LATEST RAP AND HRRR MODELS SHOW
SOME DEVELOPMENT TAKING PLACE AS EARLY AS SUNRISE NEAR THE
SOUTHERN OUTFLOW...AND AFTERNOON DEVELOPMENT SHOULD ACCOMPANY THE
NORTHERN BOUNDARY. HAVE GONE A LITTLE MORE AGGRESSIVE WITH THE
POPS AS A RESULT WITH 30-40 PERCENT MOST AREAS TODAY.
OVERNIGHT PROBLEM THEN SHIFTS TO TRACK OF THE NEXT MCS WHICH
SHOULD FORM OVER IOWA THIS EVENING. NAM AND GFS ARE MORE
PROGRESSIVE WITH SPREADING IT OVER MUCH OF ILLINOIS BY EARLY
MONDAY MORNING...WHILE THE LATEST ECMWF IS SLOWER AND SHUNTS MOST
OF IT OFF TO OUR NORTH. LEANING TOWARD A MORE SOUTHERN SOLUTION AT
THE MOMENT WITH 40-50 PERCENT POPS FROM ABOUT I-55 NORTHWEST...
WITH MAINLY SLIGHT CHANCES ACROSS THE SOUTHEAST. ONCE THIS
PARTICULAR MCS EXITS ON MONDAY...THE STORM TRACK FOR THE NEXT
ROUND SHIFTS A BIT FURTHER NORTH AS SOME UPPER RIDGING BUILDS INTO
THE MID-MISSISSIPPI VALLEY.
TEMPERATURE-WISE...STILL LOOKING LIKE 90 DEGREES OR A BIT HIGHER
IS LIKELY THE NEXT FEW DAYS...PROVIDED THE STORMS DO NOT GET OUT
OF CONTROL. SLOW BUILD OF THE DEW POINTS TOWARD THE MID 70S WILL
RESULT IN HEAT INDEX VALUES A FEW DEGREES HIGHER EACH DAY...WITH
MOST AREAS JUST ABOVE 100 FOR HEAT INDEX BY TUESDAY AFTERNOON.
LONG TERM...WEDNESDAY THROUGH SATURDAY...
SUMMER-TIME PATTERN TO CONTINUE THROUGH MID WEEK. MAIN STORM TRACK
WILL BE ACROSS THE NORTH CENTRAL STATES...WITH SOME POTENTIAL FOR
SHOWERS/STORMS FURTHER SOUTH AS THE OUTFLOWS FROM THE NIGHTLY MCS
SYSTEMS DROP INTO OUR AREA. BEST CHANCE OF RAIN WILL PROBABLY BE
WEDNESDAY NIGHT...AS A SHORTWAVE DROPS INTO THE MIDWEST ALONG WITH
AN ASSOCIATED SURFACE BOUNDARY.
AS THE END OF THE WEEK PROGRESSES...UPPER LEVEL RIDGING WILL BUILD
ACROSS THE ROCKIES...WITH A NORTHWEST FLOW BRINGING COOLER
CONDITIONS TO THE MIDWEST FOR FRIDAY AND ESPECIALLY THE WEEKEND.
THINK MOST OF THE RAIN THREAT WILL BE OUT OF THE AREA BY THURSDAY
EVENING...BUT WEAK TROUGHS ROTATING THROUGH THE MIDWEST MAY
COMPLICATE THIS THINKING.
GEELHART
&&
.AVIATION...
ISSUED 532 AM CDT SUN JUN 23 2013
COVERAGE OF CONVECTION THIS PERIOD AND ITS AFFECT ON CIGS/VSBYS
THE MAIN FORECAST CHALLENGE. REMNANT CONVECTIVELY INDUCED VORT
MAX OVER SOUTH CENTRAL IL THIS MORNING TRYING TO KICK OFF SOME
MORE SHOWERS AND THUNDERSTORMS OVER SE AND SRN IL...SOUTH OF OUR
TAF SITES. EXPECT THAT AREA TO FILL IN LATER THIS MORNING...POSSIBLY
AFFECT KCMI AFTR 15Z. ADDITIONAL CONVECTION WILL BE POSSIBLE ACRS
THE WEST LATER THIS AFTN AS STORMS ACRS IOWA RE-ITENSIFY JUST WEST
OF THE MISSISSIPPI RIVER AND THEN HEAD EAST. SOME OF THE MODELS
TRY TO CURE THOSE STORMS MORE TO THE SE WHILE OPERATIONAL MODELS
SUGGEST MORE OF AN EASTWARD TRACK WHICH WOULD INCLUDE ALL OF OUR
SITES LATE THIS AFTN AND EARLY THIS EVENING. WILL STILL INCLUDE
VCTS DURING THE TIME FRAME WE THINK THE STORMS WILL BE MOVING
THRU...AND THEN ONCE CONFIDENCE INCREASES WITH RESPECT TO TIMING
AND COVERAGE...WE WOULD THEN BE ABLE TO PIN DOWN A TIME FRAME FOR
A TEMPO GROUP.
AWAY FROM THE SHOWERS AND TSRA...WE CAN EXPECT VFR CONDITIONS...BUT
ANY TAF AREA THAT SEES THE PRECIP MAY EXPERIENCE SOME BRIEF MVFR AND
LOCALLY IFR CIGS AND VSBYS IN SOME OF THE HEAVIER PRECIP. SFC WINDS
WILL REMAIN OUT OF THE SOUTH TODAY WITH SPEEDS OF 10 TO 15 KTS WITH
OCCASIONAL GUSTS UP TO 20 KTS BEFORE WINDS DIMINISH TO AROUND 10 KTS
THIS EVENING.
SMITH
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WICHITA KS
902 AM CDT SUN JUN 23 2013
.UPDATE...
ISSUED AT 902 AM CDT SUN JUN 23 2013
PERSISTENT 315-320K ISENTROPIC ASCENT AMIDST A MOIST/UNSTABLE
AIRMASS AS DEPICTED BY RUC SHOULD ALLOW ISOLATED TO WIDELY
SCATTERED SHOWERS/THUNDERSTORMS TO LINGER THROUGH A GOOD PORTION
OF THE MORNING OVER PORTIONS OF EAST-CENTRAL AND SOUTH-CENTRAL KS.
ACTIVITY IS LIKELY ROOTED AT AND ABOVE 700MB...SO AVAILABLE
INSTABILITY TO WORK WITH ISN`T FANTASTIC FOR HAIL PRODUCTION...BUT
PROBABLY ENOUGH FOR SMALL HAIL IN THE STRONGEST CORES. AS
ATMOSPHERE BECOMES BETTER MIXED WITH DAYTIME HEATING AND 800-600MB
FLOW BACKS...ANTICIPATE THIS ACTIVITY TO GRADUALLY DISSIPATE BY
AROUND LUNCHTIME.
ADK
&&
UPDATE ISSUED AT 720 AM CDT SUN JUN 23 2013
SCT -SHRA THAT DEVELOPED BETWEEN I-135 & I-35 ~600AM HAVE SLOWLY BUT
GRADUALLY STRENGTHENED WITH ISOLD -TSRA BEGINNING TO APPEAR OVER NW
BUTLER COUNTY AT 7AM. HAVE UPDATED ALL POP-RELATED GRIDS TO DEPICT
THIS TREND. ALSO ADJUSTED POPS FOR THIS AFTERNOON TO BETTER ALIGN
WITH ANTICIPATED COVERAGE & INTENSITY OF TSRA.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 236 AM CDT SUN JUN 23 2013
LEE LOW WILL PERSIST NEAR THE CO/KS BORDER DURING THE PERIOD BENEATH
SOUTHWESTERLY MID-LEVEL FLOW PATTERN. THIS WILL MAINTAIN STRONG A
THERMAL RIDGE AND VERY WARM TEMPERATURES IN OUR AREA ALONG WITH
GUSTY SOUTHERLY WINDS. A WEAK COLD FRONT POSSIBLY AIDED BY
CONVECTIVE OUTFLOW FROM MCS IN NEBRASKA...WILL SINK INTO
NORTHWESTERN KS THIS MORNING BEFORE STALLING. VERY STRONG
INSTABILITY WILL DEVELOP THIS AFTERNOON IN OUR AREA AND NORTH OF THE
FRONT WHERE LOW-LEVEL MOISTURE WILL BE POOLING. A FEW STORMS MAY
TRY TO GET GOING IN THE WEAK FRONTAL CONVERGENCE ZONE LATE THIS PM
ALTHOUGH CONVECTIVE INHIBITION MAY BE TOO STRONG TO OVERCOME. THE
MORE PROBABLE SCENARIO IS THAT STORMS WILL FORM OVER THE HIGHER
TERRAIN TO OUR WEST/NORTHWEST IN UPSLOPE FLOW IN THE PM/EVE...AND MOVE
EASTWARD VIA CORFIDI PROPAGATION VECTORS SUNDAY NIGHT ACROSS
NORTHERN KS/SOUTHERN NEB AS AN MCS CLUSTER OR TWO. THIS ACTIVITY
WILL BE AIDED BY A WEAK SHORTWAVE OVER SOUTHERN CA EARLY THIS AM.
THIS COULD AFFECT OUR CENTRAL KS COUNTIES ESP NEAR/NORTH OF I-70.
STRONG-SEVERE WIND GUSTS COULD ACCOMPANY ANY STORMS THIS PM AND
TONIGHT WITH DCAPES OF 1500-2000 J/KG. THE PROGGED FRONTAL
SURFACE/OUTFLOW BOUNDARY SHOULD LIFT NORTH OF OUR AREA MONDAY WITH
STRONG SOUTHERLY WINDS DEVELOPING IN CENTRAL/SOUTH CENTRAL KS. A
WIND ADVISORY MAY BE REQUIRED.
JMC
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 236 AM CDT SUN JUN 23 2013
THE MEDIUM RANGE MODELS REMAIN CONSISTENT IN DEPICTING AN AMPLIFYING
UPPER PATTERN ACROSS THE CONUS...FEATURING A STRONG UPPER LEVEL HIGH
DEVELOPING OVER THE SOUTHERN ROCKIES WITH UPPER TROUGHING DEEPENING
OVER THE NORTHEAST. WEDNESDAY INTO THURSDAY WILL REMAIN HOT WITH
HIGHS 100-103 IN CENTRAL/SOUTH CENTRAL KS...AND UPPER 90S SOUTHEAST.
THE UPPER FLOW PATTERN WILL ALLOW A WEAK COLD FRONT TO PUSH SLOWLY
SOUTHWARD THROUGH OUR AREA WITH SLIGHTLY COOLER/LESS HOT WEATHER BY
FRIDAY/SATURDAY. VERY SLIGHT CHANCE OF THUNDERSTORMS AS THE FRONT
MOVES THROUGH...TIED MAINLY TO WEAK FRONTAL CONVERGENCE AND STRONG
DIURNAL HEATING. NOT OPTIMISTIC THAT MANY PLACES WILL GET RAIN HOWEVER.
JMC
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 720 AM CDT SUN JUN 23 2013
DRAWING IMMEDIATE ATTENTION IS SCT -TSRA THAT ARE SLOWLY STRENGTHENING
BETWEEN I-135 & I-35 THIS MORNING. --RA OCCURRED AT KICT 625-640AM BUT
HAVE MOVED NE OF THE TERMINAL. STILL CLOSE ENOUGH TO WARRANT A "VCTS"
TIL 15Z. S WINDS TO INCREASE CONSIDERABLY OVER MOST AREAS LATE THIS
MORNING (KRSL THE EXCEPTION) AS WEAK COLD FRONT STALLS IN NE-SW MANNER
FROM ERN NEBRASKA TO SW KS. FRONT TO BECOME FOCUS FOR INCREASED TSRA
LATE THIS AFTERNOON WITH COVERAGE SLOWLY SPREADING W/SW FROM NRN TO
SW KS. HAVE KEPT "VCTS" INTACT FOR ALL AFFECTED TERMINALS BUT DETAILS
WILL BE PROVIDED...ESPECIALLY FROM 24/00Z ISSUANCE ONWARD.
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 95 74 95 76 / 10 10 10 0
HUTCHINSON 97 74 97 76 / 10 20 10 10
NEWTON 94 74 95 75 / 20 10 10 0
ELDORADO 92 74 93 75 / 20 10 10 0
WINFIELD-KWLD 94 74 94 76 / 10 10 10 0
RUSSELL 98 70 99 75 / 20 40 10 10
GREAT BEND 98 71 99 75 / 10 30 10 10
SALINA 96 72 97 76 / 30 40 10 10
MCPHERSON 96 74 96 76 / 20 20 10 10
COFFEYVILLE 91 74 92 75 / 10 10 10 0
CHANUTE 91 74 91 75 / 10 10 10 0
IOLA 91 74 91 74 / 10 10 10 0
PARSONS-KPPF 90 74 91 75 / 10 10 10 0
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
956 AM 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 LOWER OUR TEMPERATURES...BUT INCREASE
THE CHANCE FOR SHOWERS ACROSS THE REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
.UPDATE...THE LATEST GYX SOUNDING FROM THIS MORNING HAS 1.72
INCHES OF PRECIPITABLE WATER. THIS WILL SUPPORT VERY HEAVY RAIN AT
TIMES AND HAVE INCREASED QPF FOR THIS AFTERNOON AND EVENING
ACROSS MOST OF THE AREA. TRAINING AND ANY UPSLOPE COMPONENT WILL
HELP BOOST RAINFALL TOTALS OVER ISOLATED AREAS.
MESO MODELS LIKE THE HRRR HAVE A GOOD HANDLE ON CONVECTION THIS
MORNING. THIS FIRST ROUND OF SHOWERS WILL REMAIN CONFINED TO THE
COAST AND SOUTHERN NH. MODELS INITIATE CONVECTION AGAIN BY
ROUGHLY 1 PM IN THE HIGHER TERRAIN BEFORE SPREADING THEM
DOWNSTREAM. AN AREA OF HEAVIER SHOWERS AND THUNDERSTORMS SHOULD
FORM A LOOSE MULTICELL LINE OVER SOUTHERN NH AND INTO SW MAINE LATE
THIS AFTERNOON. BREAKS IN CLOUD COVER HAS ALLOWED MUCH OF NH TO
RECEIVE INSOLATION. IF SEVERE WEATHER DOES DEVELOP...IT WOULD
MOST LIKELY OCCUR OVER SOUTHERN AND CENTRAL NH.
&&
PREVIOUS DISCUSSION...ATTM ONE S/WV IS SHEARING OUT TO THE
E...WHILE A SECOND ENTERS THE WNW FLOW FROM THE UPPER MIDWEST
CONVECTION TO OUR W. THE LEAD S/WV IS DRIVING SCT CONVECTION
ACROSS THE NORTHEAST...PERCOLATING ON THE EDGE OF BUILDING HEAT
DOME. THIS ACTIVITY WILL LIKELY CONTINUE INTO THE MORNING...AS
TRAILING S/WV INDUCES SOME FASTER MID LVL FLOW FROM THE WSW.
AS EVIDENT ON SATELLITE FOG PRODUCT ALREADY...SOME BREAKS IN THE
CLOUDS ARE APPEARING ON THE SRN EDGE OF THESE SHRA/TSTMS. THIS
WILL ALLOW STRONG INSOLATION TO TAKE PLACE EARLY IN THE DAY. TEMPS
SHOULD QUICKLY RISE THRU THE 70S...REACHING THE UPPER 80S IN FAR
SRN ZONES. CLOUDS AND ONSHORE COMPONENT TO THE WINDS FARTHER E
WILL LIMIT OVERALL HIGH TEMPS. HOWEVER...INCREASINGLY MOIST AIR
MASS WILL MAKE IT FEEL MUGGY ACROSS THE WHOLE AREA.
QUESTION THEN BECOMES CONVECTIVE ACTIVITY THIS AFTERNOON. CRUDELY
TAKING THE 23/00Z GYX SOUNDING AND MODIFYING FOR EXPECTED
AFTERNOON TEMP AND DEW POINT FOR THE FOOTHILLS REGION...ABOUT
83/65...YIELDS ROUGHLY 1500 J/KG CAPE. WITH NO STRONG ADVECTIVE
PROCESSES TAKING PLACE THIS SEEMS REASONABLE. SOME MODEL GUIDANCE
IS AGGRESSIVELY JUICING THE LLVLS WITH UPPER 60S TO NEAR 70 DEW
POINTS AND PRODUCING CAPE WELL OVER 2000 J/KG. NOT EXPECTED THIS
KIND OF INSTABILITY TODAY...BUT RATHER 1000 TO 1500...WHICH IS MORE
THAN ENOUGH FOR STRONGER STORMS.
HOWEVER...WITH RIDGING IN PLACE AT H5 THERE LACKS A DISCERNIBLE
TRIGGER TO SPARK TSTM DEVELOPMENT. MOST LIKELY WE/LL HAVE TO RELY
ON STRONG DIURNAL HEATING. WILL HAVE TO MONITOR UPSTREAM S/WV TO
SEE IF THIS SUBTLE FEATURE CAN ASSIST IN CONVECTIVE INITIATION.
CONVECTION ALLOWING MODELS ARE IN REASONABLE AGREEMENT THAT
DEVELOP OCCURS TODAY IN VICINITY OF THE NRN HUDSON AND CHAMPLAIN
VALLEYS. THIS ACTIVITY SPILLS OVER INTO WRN ZONES BY MID
AFTERNOON. FOR NOW HAVE KEPT POP IN THE SCT TO ISOLATED
RANGE...GIVEN THE UNCERTAINTY IN THE FORECAST.
PWATS PUSHING 2 SD ABOVE NORMAL POINT TOWARDS HEAVY RAINFALL BEING
THE MAIN THREAT WITH AFTERNOON CONVECTION. GIVEN THE FORECAST WIND
FIELD ALOFT...STORM MOTION SHOULD BE AOB 20 KT FROM THE WNW. SLOW
STORM MOTION COULD YIELD SOME LOCALIZED FLOODING IF STORMS TRAIN
OVER THE SAME AREAS. SHEAR AND INSTABILITY FAIL TO OVERLAP WELL
THIS AFTERNOON...SO WIDESPREAD ORGANIZED STORMS APPEAR UNLIKELY.
HOWEVER...MULTICELL CLUSTERS...STORM MERGERS...AND PRECIP LOADING
IN THE COLUMN COULD LEAD TO A FEW GUSTY STORMS AND AN ISOLATED
SEVERE WIND GUST. STRONG HEATING IN THE LOW LEVELS WILL BRING
0-3 KM LAPSE RATES UP TOWARDS 8 C/KM. THIS IS MORE THAN SUPPORTIVE
OF GUSTY OUTFLOWS. FREEZING LVLS ARE HIGH...BUT SUFFICIENT CAPE
EXISTS IN THE -10 TO -30 C LAYER TO GET SOME SUB SEVERE HAIL.
CONVECTION WILL WANE QUICKLY AFTER SUNSET...AS LACK OF STRONG
FORCING WILL LEAVE STORMS DEPENDENT ON DAYTIME HEATING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
REMAINING SHRA/TSTMS WILL CONTINUE TO WEAKEN OVERNIGHT. A FEW SHRA
COULD LINGER ON THE EDGE OF THE CAP IN THE FAR NRN ZONES AGAIN
INTO THE MORNING. ANOTHER WARM AND MUGGY NIGHT IS EXPECTED...WITH
PATCHY FOG...ESPECIALLY IN AREAS THAT RECEIVE RAINFALL THEN CLEAR
OUT.
ANOTHER HAZY...HOT...AND HUMID DAY WILL MEAN ANOTHER AFTERNOON
WITH MODERATE INSTABILITY. DIURNAL SHRA/TSTMS WILL BE PSBL AGAIN
DUE TO STRONG INSOLATION...BUT AGAIN THERE LACKS FORCING
OTHERWISE. MORE NOTICEABLE MAY BE TEMPS RISING INTO THE 80S WITH
DEW POINTS PUSHING 70. THIS WILL MEAN APPARENT TEMPS IN THE
90S...AND THE THREAT OF HEAT STRESS FOR ANYONE WITH ACTIVITIES
OUTDOORS DURING MIDDAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
THE PATTERN WILL BE VERY SIMILAR OVER THE NEXT FEW DAYS FROM TOWN
TO TOWN. A STRENGTHENING WESTERLY FLOW ALOFT WILL ALLOW
INCREASINGLY WARMER AND MORE MUGGY AIR INTO THE REGION. ON
MONDAY...EXPECT A FEW HIGH TEMPERATURES TO TOP OUT ABOVE 90
DEGREES OVER SOUTHERN NEW HAMPSHIRE AS 850 MB TEMPS REACH +18C.
THERE WILL BE SCATTERED SHOWERS AND THUNDERSTORMS...MAINLY DURING
THE AFTERNOON AND EARLY EVENING HOURS AS A SHORT WAVE CROSSES THE
REGION. THERE COULD BE A FEW STORMS ON MONDAY WITH DAMAGING WIND
GUSTS AS CAPES AND PRECIPITABLE WATER VALUES REMAIN HIGH.
SIMILAR CONDITIONS WILL CONTINUE ON TUESDAY...WITH MAINLY
NOCTURNAL SHOWERS AND THUNDERSTORMS ACROSS THE REGION.
MODELS VARY ON WHETHER A BACKDOOR COLD FRONT WILL CROSS THE REGION
BY EARLY WEDNESDAY. IN ANY CASE...WINDS WILL VEER WITH TIME ON
WEDNESDAY...ALLOWING SLIGHTLY COOLER AIR INTO THE REGION AFTER A
WARM START.
00Z MODEL SUITE IN RELATIVELY CLOSE AGREEMENT BY THURSDAY AS LARGE
TROUGH APPROACHES FROM THE WEST. THIS ALLOWS A SOUTHERLY SURFACE
FLOW TO DEVELOP OFF THE CHILLY BRINK OF THE GULF OF MAINE AND THE
ATLANTIC SEABOARD...DROPPING OUR TEMPS ACROSS THE REGION AND ALSO
INCREASING OUR CHANCES OF RAINFALL FOR LATE IN THE WEEK. A
WET...SHOWERY PATTERN WILL CONTINUE RIGHT INTO THE WEEKEND.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...PATCHY VALLEY FOG WILL PERSIST INTO THE
MORNING...WITH OTHERWISE VFR HZ. SCT SHRA/TSTMS THIS AFTERNOON ARE
EXPECTED FOR THE AREA...ESPECIALLY KHIE...KLEB...AND KCON. ANY
SHRA/TSTM COULD BRING MVFR OR LOWER CONDS. SOME PATCHY FOG IS
POSSIBLE AGAIN TONIGHT. SCT TO ISOLATED TSTMS ON MON COULD BRING
MORE LOCAL MVFR OR LOWER CONDS.
LONG TERM...
EXPECT NOCTURNAL FOG TO BE THE ONLY MAJOR FLIGHT RESTRICTIONS
OVER THE NEXT SEVERAL DAYS. SHOWERS AND THUNDERSTORMS ARE POSSIBLE
EACH AFTERNOON...ESPECIALLY AT INLAND TERMINALS.
&&
.MARINE...
SHORT TERM...WINDS AND SEAS ARE EXPECTED TO REMAIN BELOW SCA
THRESHOLDS FOR THE PERIOD. AN ISOLATED GUST NEAR 25 KT OR WAVE
NEAR 5 FT IS POSSIBLE THIS AFTERNOON.
LONG TERM...
LIGHT SOUTHWEST FLOW EXPECTED AROUND HIGH PRESSURE TO THE EAST FOR
MUCH OF THE WEEK.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
UPDATE...HANES
LEGRO/JC
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1121 AM EDT SUN JUN 23 2013
.SYNOPSIS...
PARTY CLOUDY SKIES AND WARM WEATHER WILL BE THE RULE THIS WEEK.
THERE WILL BE A CHANCE OF SHOWERS OR A THUNDERSTORM ESPECIALLY IN
AFTERNOON AND EARLY EVENING EACH DAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
1115 UPDATE...
CHALLENGING FORECAST FOR THIS AFTERNOON. CONVECTIVE CHANCES HAVE A
LOT OF COMPETING PARAMETERS TODAY. BIG PLUME OF HIGHER PWATS OVER
VA WILL PASS EAST OF THE AREA TODAY. STILL NOT A LOT OF DEEP LOW
LEVEL MOISTURE IN AREA SOUNDINGS SUGGUESTING THAT INSTABILITY WILL
PEAK BY EARLY AFTERNOON AND THEN DECREASE LATER TODAY AS THE
BOUNDARY LAYER DEEPENS AND DRY AIR MIXES IN. OVERALL STILL THINK
THAT SLIGHT CHANCE TO LOW CHANCE POPS ARE WARRANTED ESPECIALLY
OVER TERRAIN. HRRR STILL SUGGESTING THAT WIDELY SCATTERED
CONVECTION WILL DEVELOP ELSEWHERE. MINIMAL CHANGES TO THE FORECAST
THIS MORNING.
MANNING
PREVIOUS...
H5 RIDGE AXIS FINALLY PUSHING ACROSS FORECAST AREA TODAY AS
WEAK UPPER LOW TN/KY SLIDES NORTHEAST. ALTHOUGH UPPER LOW
WEAKENING...A LITTLE COLDER TEMPERATURES (-10 TO -12C) WILL
TRANSLATE WITH LOW. DEW POINTS EXPECTED AT LEAST IN THE MID TO
UPPER 60S. THE COMBINATION OF A LITTLE STEEPER MID-TROPOSPHERIC
LAPSE RATES (MORE INSTABILITY) AND SIGNIFICANT LOW LEVEL MOISTURE
WILL GIVE US A CHANCE OF AFTERNOON OR EVENING SHOWERS OR A
THUNDERSTORM. WILL CARRY A 30 POP THIS AFTERNOON INTO THIS
EVENING. AREA OF SIGNIFICANT PRECIPITABLE WATER (ALMOST 2 INCHES)
LOCATED VIRGINIA PIEDMONT THIS MORNING. HOWEVER, NOT SURE THIS
REALLY JUICY AIR WILL MAKE IT THIS FAR NORTH AND WEST. BEST
MOISTURE FLUX AND MOISTURE TRANSPORT WOULD GIVE US A GLANCING BLOW
AT BEST AND SUGGEST THAT BEST PW/S MIGHT PUSH OFF TO OUR EAST AS
REMNANT LOW MOVES NORTH EAST. HOWEVER...WITH RELATIVELY SLOW
MOVEMENT OF ANY CONVECTION AND RESPECTABLE MOISTURE COULD STILL
GET SIGNIFICANT DOWNPOUR IN ANY CONVECTION.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
RATHER FLAT UPPER H5 FLOW INTO MONDAY...HOWEVER WEAK IMPULSE IN
UPPER FLOW AND DIURNAL HEATING ADDING INSTABILITY...SO WILL
CONTINUE WITH CHANCE POPS OF SHOWERS AND THUNDERSTORM...ESPECIALLY
LATE AFTERNOON AND EVENING. ON TUESDAY...A LITTLE STRONG UPPER
LEVEL SHORT WAVE PUSHES EAST IN A GENERAL ZONAL H5 FLOW. THE ADDED
MID-TROPOSPHERIC LIFT COMBINED WITH ADDED INSTABILITY AND A TAD BIT
MORE SHEAR SHOULD GIVE US A LITTLE BETTER CHANCE OF SHOWERS AND
THUNDERSTORMS AND WENT WITH NEAR 50 POP FOR AFTERNOON AND EVENING.
NAM A LITTLE FASTER WITH THIS IMPULSE THAN GFS...BUT BOTH MODELS
EXHIBIT A BROADER PRECIP FIELD WITH APPROACH OF THIS UPPER SHORT
WAVE.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
THE MODELS CONTINUE TO SUPPORT A SHIFT FROM A ZONAL PATTERN TO A
MORE AMPLIFIED ONE AS A RIDGE BUILDS OVER THE WESTERN CONUS THROUGH
THE WEEK. HOWEVER...EACH MODEL CONTINUES TO HANDLE THE SERIES OF
FAST MOVING SHORTWAVES EMBEDDED WITHIN THE FLOW DIFFERENTLY. WITH
LOWER CONFIDENCE...KEPT POPS MOSTLY IN THE CHANCE CATEGORY FOR MUCH
OF THE FORECAST PERIOD UNTIL BOTH THE GFS...ECMWF...AND THE ENSEMBLE
MEANS SWING A COLD FRONT ACROSS THE REGION OVER THE WEEKEND. DESPITE
THE BLANKET CHANCE POPS...THINK THAT MUCH OF THE CONVECTION WILL
REMAIN DIURNALLY DRIVEN THROUGH THE PERIOD. IN ADDITION...ALL
GUIDANCE CONTINUES TO SUGGEST TEMPERATURES WILL BE ABOVE SEASONAL
AVERAGES UNTIL THE COLD FRONT PASSAGE.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
GENERAL VFR CONDITIONS ARE EXPECTED THROUGH MUCH OF THE TAF PERIOD
AS HIGH PRESSURE SHIFTS OFF EAST AND A CUTOFF UPPER LOW SLOWLY
WOBBLES NORTHWARD TOWARD THE REGION. WHILE THIS LOW COULD LEAD TO
A BETTER FOCUS FOR CONVECTION...MOST OF THE GUIDANCE STILL
SUGGESTS COVERAGE WILL BE WIDELY SCATTERED. THUS...WILL LEAVE THE
THUNDER MENTION OUT OF ANY TAF SITES FOR NOW. DIURNAL CUMULUS IS
EXPECTED AFTER SUNRISE. SOUTHWESTERLY WINDS OF 5-10KTS ARE
EXPECTED THROUGH THE AFTERNOON.
OUTLOOK.../SUNDAY THROUGH THURSDAY/...
GENERALLY VFR BUT WITH INCREASING CHANCES FOR SOME EARLY MORNING FOG
AS HUMIDITY INCREASES. SCATTERED SHOWERS AND THUNDERSTORMS
WILL RETURN TO THE FORECAST FOR SUNDAY AFTERNOON THROUGH AT LEAST
MIDWEEK.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BILLINGS MT
915 AM MDT SUN JUN 23 2013
.UPDATE...
ZONAL FLOW HAS SET UP ACROSS THE AREA TODAY IN THE WAKE OF
YESTERDAYS SHORT WAVE TROUGH. SURFACE LOW OVER NORTHERN NORTH
DAKOTA IS WRAPPING PRECIPITATION BACK INTO NORTHEAST MONTANA THIS
MORNING BUT RAIN WILL STAY NORTH OF FALLON COUNTY. HAVE REMOVED
POPS THERE FOR THIS MORNING. WESTERLY FLOW WILL BRING DRIER AIR
INTO THE FORECAST TODAY AND TEMPERATURES WILL WARM INTO THE MID TO
UPPER 70S AT MOST LOCATIONS. 12Z TEMPERATURE GUIDANCE AGREES WELL
WITH CURRENT FORECAST HIGHS AND NO CHANGES MADE. ONLY OTHER CHANGE
WAS TO LOWER CLOUD COVER OVER OUR NORTHEAST ZONES THIS MORNING.
RICHMOND
&&
.SHORT TERM...VALID FOR TDY AND MON...
A WARMING TREND IS IN STORE TODAY AND MON IN THE WAKE OF THE SHORT
WAVE TROUGH WHICH BROUGHT MOISTURE SAT. OUR ATTENTION WILL TURN TO
A CONDITIONAL RISK OF SEVERE STORMS IN SOUTHEASTERN MT BY MON AS A
PLUME OF HIGHER BOUNDARY LAYER MOISTURE TRIES TO MAKE A RUN TOWARD
AT LEAST BAKER JUST AS 500-HPA FLOW BECOMES SOUTHWEST ONCE MORE.
TODAY...A DRYING AND WELL-MIXED AIR MASS WILL YIELD A WARM DAY. WE
HAVE HIGHS A BIT ABOVE THE 00 UTC MULTI-MODEL CONSENSUS OVER PARTS
OF THE AREA IN RESPECT TO EXPECTED MIXING...WHICH SHOULD EXTEND TO
600 HPA IN SOUTH CENTRAL MT AND 700 HPA IN SOUTHEASTERN MT. ONLY A
LOW POP WAS RETAINED IN BAKER THIS MORNING. WE ALSO WENT WITHOUT A
MENTION OF FOG...AS VISIBILITIES OVER SOUTHEASTERN MT HAVE COME UP
SINCE 06 UTC AS WINDS BECAME WEST-SOUTHWEST. HRRR OUTPUT ALSO SAYS
MOST OF THE FOG WILL STAY NORTH AND EAST OF THE AREA THIS MORNING.
TONIGHT...A QUIET PERIOD IS IN STORE FOR MOST OF THE AREA...BUT WE
WILL NEED TO CONSIDER THE POTENTIAL FOR ELEVATED CONVECTION ACROSS
SOUTHEASTERN MT WITH LATER FORECASTS. SERIOUS THOUGHT WAS GIVEN TO
ADDING SOME LOW POPS FOR STORMS AFTER 09 UTC TO AT LEAST BAKER AND
EKALAKA AS A 30 KT LOW-LEVEL JET DEVELOPS. THE 00 UTC GUIDANCE ALL
SHOWS A GRADIENT IN NEGATIVE SHOWALTER INDICES NORMAL TO THAT LOW-
LEVEL JET TOO...WHICH CAN OFTEN BE A GOOD FORECAST SIGNAL FOR SOME
NOCTURNAL STORMS. HOWEVER...HEIGHTS ALOFT WILL BE RISING TOO...AND
THE SUBSIDENCE ASSOCIATED WITH THAT PROCESS CAN DETER DEVELOPMENT.
THUS...WE LEFT A DRY FORECAST IN TACT TONIGHT. NOTE THOUGH THAT WE
ALREADY HAD LOW POPS IN BAKER AND EKALAKA FROM 12 TO 18 UTC ON MON
AND THUS THOSE WERE LEFT IN PLAY.
MON...A MID-LEVEL THERMAL RIDGE WITH 700-HPA TEMPERATURES FROM +11
TO +13 C WILL CROSS THE AREA...LEADING TO HIGHS WELL INTO THE 80S.
MIXING MAY BE SUFFICIENT FOR A CRACK AT 90 F...ESPECIALLY IN SOUTH
CENTRAL MT. GUIDANCE AGREES THAT A LEE TROUGH AND SURFACE LOW WILL
FORM OVER THE AREA...AND SOUTH-SOUTHEAST FLOW SHOULD HAVE A CHANCE
OF PULLING HIGHER DEWPOINTS INTO SOUTHEASTERN MT. MOST MODELS SHOW
SURFACE DEWPOINTS OF 55 TO 60 F AROUND BAKER AND EKALAKA BENEATH A
PLUME OF STEEP MID-LEVEL LAPSE RATES IN EXCESS OF 8 C/KM. ONLY ONE
MEMBER OF THE 21 UTC SREF HAS LESS THAN 1800 J/KG OF MLCAPE ACROSS
THAT AREA BY PEAK HEATING...AND MOST HAVE VALUES OF 2500 J/KG JUST
LIKE THE 00 UTC NAM AND ECMWF SUPPORT. SURFACE HEATING WILL LIKELY
BE ENOUGH TO REMOVE MLCIN...BUT FORCING IS IN QUESTION SINCE THERE
MAY NOT BE MUCH LOW-LEVEL MASS CONVERGENCE IN PLACE. THE CHANCE OF
SEVERE STORMS DRIVEN BY EXPECTED MLCAPE AND VEERING /THOUGH RATHER
MODEST/ WIND PROFILES IS THUS HIGHLY CONDITIONAL ON STORMS GETTING
GOING IN THE FIRST PLACE. MEANWHILE...WE WILL ALSO HAVE CHANCES OF
SOME WEAKER AND HIGH-BASED STORMS ELSEWHERE...ESPECIALLY CLOSER TO
LIVINGSTON WHERE HEIGHTS ALOFT WILL FALL A BIT BY 00 UTC. SCHULTZ
.LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT...
OVERALL THEME OF THE EXTENDED REMAINS IN TACT WITH A RIDGE
PROGGED TO BUILD TO END THE WEEK INTO NEXT WEEKEND. THE TIMING OF
MID LEVEL HEIGHT INCREASES KEEPS BEING DELAYED LITTLE BY LITTLE. A
SHORTWAVE TROUGH WILL MOVE THROUGH THE AREA EARLY IN THE DAY.
TIMING OF THE WAVE MAY LIMIT CONVECTION CHANCES BUT WILL KEEP
SCATTERED POPS IN AS STILL A FEW DAYS OUT TO GET THE TIMING OF
THIS WAVE DOWN. THE SHORTWAVE ZIPS EAST AND VEERS THE FLOW TO THE
WEST FOR ZONAL FLOW WEDNESDAY. THIS WILL SET UP A PERIOD OF DRY
WEATHER AS THE UPPER RIDGE TO THE SOUTH STARTS TO BUILD IN EARNEST
WEDNESDAY NIGHT.
WILL HAVE TO WATCH RIDGE RIDING SHORTWAVES FROM FRIDAY ONWARD AS
THE TAP TO PACIFIC MOISTURE MAY BE ENOUGH TO TRIGGER CONVECTION.
LOW LEVEL FLOW LOOKS TO BE EASTERLY DURING THIS PERIOD WHICH WILL
KEEP DEWPOINTS UP. LIMITING FACTOR FOR CONVECTION WILL BE THE
STRENGTH OF THE RIDGE ITSELF. WILL KEEP POPS OUT FRIDAY. DID ADD
THEM SATURDAY AS BOTH THE GFS AND ECMWF WERE FAIRLY AGGRESSIVE IN
SLIDING A CHUNK OF ENERGY WITH MID LEVEL MOISTURE INTO THE AREA.
THE MAIN BUILDING OF THE RIDGE HAS HELD OFF UNTIL EARLY NEXT WEEK
AND THE MODELS WERE HAVING DIFFICULTY WITH CONSISTENCY ON THIS.
THE CONSENSUS DOES SEEM TO BE TO DELAY THE HIGHER HEIGHTS AND TO
SHIFT THE AXIS INTO THE GREAT BASIN. THIS POSITION WOULD KEEP THE
POSSIBILITY OF BACK DOOR COOL FRONTS IN PLAY AND WOULD SUPPRESS
MONSOONAL TYPE OF MOISTURE FROM WRAPPING INTO THE STATE. TWH
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL ACROSS ALL FLIGHT TERMINALS TODAY
THROUGH TONIGHT. RICHMOND
&&
.PRELIMINARY POINT TEMP/POPS...
TDY MON TUE WED THU FRI SAT
-------------------------------------------------------
BIL 078 053/088 062/086 058/087 059/088 059/089 059/090
1/U 11/B 23/T 21/B 10/U 00/U 02/T
LVM 078 044/085 054/081 053/083 052/084 053/085 053/086
1/B 13/T 34/T 21/B 11/U 11/U 12/T
HDN 080 051/089 059/088 057/089 059/090 059/091 059/093
1/U 11/B 23/T 21/B 11/U 10/U 01/U
MLS 078 056/089 062/088 060/088 059/087 060/087 060/089
1/U 12/T 23/T 21/B 10/U 01/U 11/U
4BQ 078 052/089 059/089 058/090 059/090 059/089 059/090
1/U 12/T 22/T 21/U 11/U 11/U 11/U
BHK 075 053/086 059/086 058/085 059/084 058/084 061/085
1/B 13/T 32/T 21/U 11/U 10/U 01/U
SHR 078 049/086 055/086 053/087 054/087 053/088 053/089
1/U 11/B 22/T 21/B 11/U 11/U 11/U
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
541 AM MDT SUN JUN 23 2013
.AVIATION...
12Z TAF CYCLE
WINDS WILL INCREASE THIS AFTERNOON WITH SOME GUSTS BETWEEN 25 TO
30 KT. VFR CONDITIONS WILL PREVAIL OUTSIDE OF ANY SHOWER/STORMS. ANY
PRECIPITATION WILL BE CONFINED WELL INTO THE FAR EASTERN PLAINS
NEAR THE TX/OK BORDERS WHERE SHOWERS AND STORMS WILL PRODUCE LOCAL
ENHANCEMENTS TO THE GUSTY WINDS. WINDS WILL DIMINISH MOST
LOCATIONS AFTER SUNSET...BUT WILL REMAIN PERSISTENTLY STRONG IN
THE EASTERN PLAINS THROUGH THE EVENING AND INTO THE EARLY MORNING
MONDAY.
52
&&
.PREV DISCUSSION...320 AM MDT SUN JUN 23 2013...
.DISCUSSION..
DRYLINE HAS MADE LESS PROGRESS WESTWARD ATTM THAN IN PREVIOUS
NIGHTS...AND AT 3 AM WAS STRETCHED FROM KROW NORTHEAST TO NEAR KCAO.
AT THE SAME TIME...A BOUNDARY FROM APPARENTLY THE CONVECTIVE COMPLEX
OVER WRN NE AND KS...OR AT LEAST AIDED BY IT...HAD SAGGED TO KLHX
AND KLAA. LATEST RUC13 INDICATES THE BOUNDARY COULD REACH KTCC OR
EVEN FARTHER SOUTH BY MIDMORNING...AND BY EARLY AFTERNOON IT COULD
BE STRETCHED FROM THE RATON AREA TO KTCC. 06Z NAM MAKES FOR AN
INTERESTING FORECAST WITH THE SURFACE LOW REMAINING CENTERED NEAR
KLVS RATHER THAN LIFTING INTO NE CO LATE THIS AFTERNOON. THIS CHANGE
COULD RESULT IN A LITTLE LESS WIND...AS WELL AS A LITTLE MORE AREAL
COVERAGE OF THE SLIGHT CHANCE POPS WE CURRENTLY HAVE PAINTED IN FAR
NE NM. OTHERWISE...SHOULD BE LESS HIGH CLOUDS AROUND TODAY WITH
LITTLE CHANGE IN HIGH TEMPERATURES FOR MOST LOCALES.
WINDS TO BE A BIT STRONGER MONDAY...SHUNTING ANY MID LEVEL MOISTURE
THAT TRIES TO WORK IT/S WAY NORTHWARD INTO SOUTHERN AND EASTERN
SECTIONS OF THE STATE...ALTHOUGH IT/S NOW FORECAST TO BE SOMEWHAT
LESS THAN PREVIOUS MODEL RUNS SUGGESTED...AND SEEPAGE INTO SOUTHWEST
NM APPEARS LESS LIKELY. STILL THERE IS PLENTY OF MOISTURE JUST SOUTH
OF THE BORDER SO LEFT POPS PRETTY MUCH ALONE. DRYLINE CAN/T SEEM TO
MAKE MUCH PROGRESS WESTWARD FOR THE NEXT FEW DAYS WITH THE LEE
TROUGH STAYING PUT. UPPER HIGH REMAINS PROGGED TO SHIFT NORTHWARD BY
TUESDAY ALLOWING WINDS TO RELAX...HEADING FOR THE FOUR CORNERS
REGION MID TO LATE WEEK. WEDNESDAY INTO THURSDAY COULD BE THE
HOTTEST DAYS OF THE WEEK FOR THE CENTRAL AND WEST. EVIDENCE OF A
FRONT INVADING THE EASTERN PLAINS FRIDAY-ISH COULD SPARK SHOWERS AND
STORMS IN THE NORTH CENTRAL/EAST. BY NEXT WEEKEND...THE HIGH CENTER
STARTS TRIPPING TOWARD SALT LAKE...WITH POTENTIAL FOR CONVECTION TO
DEVELOP OVER THE NRN HIGH TERRAIN AND DRIFT SOUTH TO SOUTHWESTWARD
INTO CENTRAL/WRN VALLEYS.
.FIRE WEATHER...
...CRITICAL FIRE WEATHER CONDITIONS EXPECTED OVER MUCH OF CENTRAL TO
EASTERN NM TODAY WITH MORE WIDESPREAD CONDITIONS ON MONDAY...
TODAY`S FORECAST WILL BE TRICKY...ESPECIALLY WITH REGARDS TO THE
WINDS. THIS WILL HAVE LARGE IMPLICATIONS ON THE DURATION AND SPATIAL
EXTENT OF CRITICAL FIRE WEATHER THIS AFTERNOON. OVERALL...THE MAIN
FEATURES THAT HAVE BEEN DICTATING THE WEATHER PATTERN THE PAST FEW
DAYS ARE STILL AT WORK...WITHOUT ANY BLATANT OR LARGE CHANGES. ANY
DIFFERENCES WILL BE FAIRLY SUBTLE. HOWEVER...MIXING HEIGHTS MAY
EXCEED YESTERDAY`S LEVELS DUE TO LESS HIGH CIRRUS CLOUDS. MODEL
DEPICTION OF MIXING HEIGHTS IS RATHER SPLOTCHY...INDICATIVE THAT IT
IS HAVING DIFFICULTY RESOLVING IT. ALSO...SOUTHWESTERLIES ALOFT
REMAIN RELATIVELY STRONG FOR LATE JUNE...HOSTING SPEEDS OF 15-20 KT
AT H7 AND UP TO 20-25 KT AT H5 WHICH SHOULD BE WITHIN THE MIXED
LAYER OF MOST SITES. THE EASTERN HALF OF THE FORECAST AREA WILL ALSO
HAVE POTENTIAL FOR A BETTER SURFACE PRESSURE GRADIENT...DEPENDING ON
WHERE THE LEE SIDE SURFACE LOW ESTABLISHES ITSELF. A CLUSTER OF
CONVECTION IN THE CENTRAL PLAINS OF THE NATION HAS HELPED USHER A
BOUNDARY SOUTHWARD INTO COLORADO. IF THIS BOUNDARY SPILLS FARTHER
SOUTH INTO NM...BEYOND WHAT MOST MODELS ARE INDICATING...IT COULD
WREAK HAVOC ON WIND FORECAST DUE TO ORIENTATION OF THE SURFACE LOW
AND ASSOCIATED GRADIENT. HUMIDITY WILL TANK LESS THAN 10 PERCENT
OVER MOST OF THE FORECAST AREA TODAY WITH THE FAR EASTERN PLAINS
NEAR TX BEING THE ONLY EXCEPTION. HIGHLY UNSTABLE AND WELL-MIXED
AIRMASS WOULD SEEM TO SUPPORT A GUSTY DAY FOR MUCH OF THE AREA...AND
BEST CONFIDENCE FOR CRITICAL WINDS EXTENDS ALONG AND EAST OF A
SOCORRO TO CLINES CORNERS TO RATON LINE...EXCLUDING SOME OF THE FAR
PLAINS ALONG THE OK/TX BORDERS. HAVE THROWN IN MIDDLE RIO GRANDE
FWZ106 TO THE WARNING. WOULD NOT BE SURPRISED TO SEE A COUPLE OF
STRAY GUSTS TO 35 MPH IN THE WEST CENTRAL ZONES...BUT CONFIDENCE IS
NOT HIGH ENOUGH TO PULL TRIGGER ON WARNING.
CONFIDENCE IS A BIT HIGHER ON MONDAY DUE TO STRONGER WIND SIGNALS
SUCH AS BETTER AGREEMENT ON THE SURFACE LOW PLACEMENT AND STRONGER
WINDS ALOFT OF 20 TO 35 KT IN THE H7-H5 LAYER. VERY DRY AIRMASS
ALOFT AND REINFORCEMENT FROM A MID LEVEL DRY SLOT WILL MAKE ANOTHER
EXTREMELY LOW RH REGIME WITH POOR RECOVERIES MONDAY MORNING AND
PROLONGED SINGLE DIGIT READINGS. HAVE EXTENDED WATCH FOR MONDAY TO
INCLUDE MIDDLE RIO GRANDE AND NORTHWESTERN AND WEST CENTRAL
HIGHLANDS/MOUNTAINS. HAVE LEFT NORTHERN MOUNTAINS AND NORTHWEST
PLATEAU OUT DUE TO LOWER CONFIDENCE IN THE WINDS...BUT THIS WILL
NEED TO BE SCRUTINIZED OVER THE NEXT 24 HOURS.
THE WINDS ALOFT DO RELAX SOME INTO TUESDAY AS THE UPPER HIGH BEGINS
TO DRIFT NORTHWARD. STILL...A SUFFICIENT LEE SIDE SURFACE LOW WILL
KEEP SOME BREEZY/WINDY CONDITIONS GOING IN THE EAST...PRIMARILY NEAR
THE I-40 CORRIDOR. INTO WEDNESDAY AND THROUGH THE REST OF THE WEEK
THE UPPER HIGH WILL ESTABLISH ITSELF OVER THE DESERT
SOUTHWEST...PERIODICALLY CENTERING NEAR OR CLOSE TO THE FOUR
CORNERS. THIS WILL SPELL DRY AND HOT CONDITIONS...BUT WITH LOW
WINDS. MOISTURE MAY FINALLY BEGIN TO ARRIVE FROM THE EAST BY THE
WEEKEND AS A BACK DOOR FRONT AND ONSHORE FLOW FROM THE GULF OF
MEXICO SEEP IN.
52
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 1 PM THIS AFTERNOON TO 8 PM MDT THIS EVENING
FOR THE FOLLOWING ZONES...NMZ102>104-106>108.
FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING FOR
THE FOLLOWING ZONES...NMZ102>109.
&&
$$
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1009 AM EDT SUN JUN 23 2013
.SYNOPSIS...
WE WILL CONTINUE OUR TREND OF A WARM AND INCREASINGLY HUMID
PATTERN. WEAK PASSING DISTURBANCES WILL RESULT IN SCATTERED
SHOWERS AND THUNDERSTORMS IN EACH OF THE NEXT SEVERAL DAYS...WITH
BEST CHANCES IN THE AFTERNOON HOURS.
&&
.NEAR TERM /THROUGH TONIGHT/...
950 AM UPDATE...
FCST IN FAIRLY GOOD SHAPE THIS MORNING...ONLY MINOR ADJUSTMENTS
NEEDED TO ACCOUNT FOR LATEST TRENDS. THAT SAID...MAIN FOCUS REMAINS
CENTERED ON POSSIBLE CONVECTION LATER THIS MORNING/AFTERNOON AS
REGION WARMS WELL INTO THE THE MIDDLE TO UPPER 80S IN A MODERATELY
MOIST AND UNSTABLE ENVIRONMENT. LATEST OBSERVATIONS ALREADY
SHOWING SYR AT 85 THIS HR AND HAVE INCREASED MAX TEMPS UPWARD A
DEGREE OR TWO IN SOME LOCATIONS.
LATE MORNING WATER VAPOR IMAGERY SHOWING A FAIRLY WELL DEFINED
SHEAR AXIS LIFTING NORTH FROM SOUTHERN PENNSYLVANIA ALONG THE
NORTHERN PERIPHERY OF AN UPPER LOW THAT CONTINUES SPINNING THIS HR
ACROSS THE CENTRAL APPALACHIANS. RUC LAYERED 500-300 MB VORTICITY
SHOWS A SERIES OF EMBEDDED VORTICITY MAXIMA SLOWLY CREEPING NORTH
TOWARDS OUR AREA. THAT SAID...MAIN UPPER FORCING FOR ANY
CONVECTION LATER TODAY WILL LIKELY ARRIVE FROM THESE EMBEDDED FEATURES
WITH ADDITIONAL LOW-LEVEL FORCING POSSIBLY BEING SUPPLIED BY
INCREASED LOW-LEVEL CONVERGENCE ALONG A WEAK SURFACE TROUGH THAT
MODELS FCST TO MOVE THROUGH THE REGION LATER TODAY. LATEST HIGH
RES MODELS SUGGEST FAIRLY ISOLATED ACTIVITY DEVELOPING LATER TODAY
AND CONSIDERING THAT THE FORCING MECHANISMS ARE FAIR WEAK IN
NATURE...HAVE ELECTED TO TRIM BACK POPS INTO THE SCATTERED
CATEGORY GOING INTO THE AFTERNOON.
ABOVE SAID...12Z BUF RAOB SHOWING A FAIR AMOUNT OF DRY AIR ALOFT
WITH STEEP MID-LEVEL LAPSE RATES. CONSIDERING THE AMOUNT OF DRY
AIR ALOFT...IF ANY CONVECTION WERE TO DEVELOP...A FEW ROGUE PULSEY
TYPE SEVERE STORMS WITH LOCALLY HEAVY RAINS CANNOT BE RULED OUT
THANKS FOR WEAK WINDS ALOFT AND SLOW STORM MOVEMENT. WILL CONTINUE
TO MONITOR AND UPDATE AS NECESSARY.
645 AM UPDATE...
LATEST HIGH RES MODEL RUNS ARE COMING INTO GOOD AGREEMENT NOW ON
WAVE BEING ABLE TO INITIATE CONVECTION...INCLUDING THE
HRRR...RAP/RUC...AND WRFARW. OPERATIONAL 06Z NAM...00Z GEM...AND
EVEN SOMEWHAT THE 06Z GFS CONCUR ON AT LEAST THE GENERAL IDEA.
GRIDS HAVE BEEN UPDATED ACCORDINGLY WITH LARGER AREA OF MORE
DETERMINISTIC 60-70 PERCENT POPS FROM FINGER LAKES EASTWARD ACROSS
THE REMAINDER OF CENTRAL NY ESPECIALLY 18Z-22Z TIME FRAME. ALSO
HIGH CHANCE POPS SINKING INTO NORTHERN TIER OF PA 20Z SUN-01Z MON
TIME FRAME.
PREVIOUS DISCUSSION...
AFTER SEVERAL DRY DAYS...AREAS NORTH OF THE NEW YORK THRUWAY
FINALLY GOT SOME SCATTERED SHOWERS SATURDAY INTO OVERNIGHT DUE TO
THE INCREASINGLY MOIST AIR MASS...AND WEAK PASSING DISTURBANCES ON
THE SOUTHERN PERIPHERY OF THE BELT OF WESTERLIES. MORE OF THE AREA
WILL GET INVOLVED IN THAT TODAY...THOUGH BEST CHANCES WILL AGAIN
BE IN CENTRAL NEW YORK.
A LOOSELY DEFINED UPPER LOW IS CURRENTLY SPINNING ON THE KY/TN
BORDER...WHILE THE MAIN BELT OF WESTERLIES CARRIES OVER FROM THE
UPPER MIDWEST THROUGH THE NORTHERN GREAT LAKES AND INTO NEW
ENGLAND. BETWEEN THOSE FEATURES...AN UPPER RIDGE STILL EXTENDS
ACROSS THE MIDATLANTIC STATES BACK TOWARDS THE UPPER OHIO VALLEY.
THE UPPER RIDGE IS LOSING ITS GRIP HOWEVER. MODELS DISAGREE ON HOW
QUICKLY MOISTURE FILLS THE VOID OF LOWER PRECIPITABLE WATER ALONG
THE RIDGE AXIS. IN ASSIGNING POPS TODAY...THE SREF APPEARS WAY
OVERDONE...AND UPSTREAM 00Z SUN SOUNDINGS IN BUFFALO NY AND WHITE
LAKE MI CONFIRM LOWER PRECIPITABLE WATER VALUES THAN SUGGESTED BY
SREF. THAT BEING SAID...THERE WILL DEFINITELY BE A GRADIENT IN
RAIN CHANCES. IT CAN BE CONFIDENTLY STATED THAT THE NORTHERN
ZONES WILL HAVE PWATS AT LEAST AROUND AN INCH-AND-TWO-
THIRDS...VERSUS THE SOUTHERN ZONES WHERE PWATS STAY UNDER AN
INCH-AND-A-HALF. IN BETWEEN...ACROSS THE TWIN TIERS...MODELS
DISAGREE ON AMOUNT OF MOISTURE AND THUS INSTABILITY.
AS A RESULT OF THE HIGHER PWATS...MODEL SOUNDINGS AGREE ON NORTHERN
ZONES HAVING MORE INSTABILITY...GREATER THAN 1000 J/KG...YET FARTHER
SOUTH IS MORE UNCERTAIN. ALSO...THE NORTHERN ZONES WILL BE MORE
PRONE TO SOME ALBEIT LIMITED FORCING FROM WEAK SHORTWAVES. I HAVE
KEYED IN ON WEAK VORTICITY WAVE THAT SHOWS UP ON GEM/NAM/WRFARW
MODELS WHICH WILL ENTER FINGER LAKES AROUND MIDDAY AND DRIFT
EASTWARD FROM THERE IN THE AFTERNOON...HIGH CHANCE TO LIKELY POPS.
RESULTANT CONVECTION WILL HAVE A FIGHT AS IT TRIES TO MAKE
SOUTHEAST PROGRESS...WITH LESS FRIENDLY AIR MASS...AND THUS LOWER
POPS. THOUGH THERE IS FAIR AMOUNT OF CONFIDENCE THAT THE
CONVECTIVE SHOWERS WILL CONTAIN THUNDER...SHEAR AND OTHER
PARAMETERS ARE LACKING AND THUS NOT EXPECTING ANY ORGANIZED
SEVERE THREAT. SPC DAY 1 CONVECTIVE OUTLOOK ONLY HAS A
BROADBRUSHED 5 PCT CHANCE OF SEVERE IN AN AXIS FROM LOWER MICHIGAN
THROUGH PARTS OF OUR REGION AND INTERIOR NEW ENGLAND.
MET AND MAV GUIDANCE WAS OVERALL JUST SLIGHTLY TOO WARM WITH
TEMPERATURES SATURDAY...AND I SUSPECT THE SAME MAY BE TRUE TODAY
CONSIDERING AMOUNT OF MOISTURE AND PROSPECTS FOR SCATTERED
CONVECTION. FOR HIGHS I BLENDED MAV/MET WITH THE SLIGHTLY COOLER
LAV GUIDANCE. STILL A WARM AND HUMID DAY...WITH HIGHS 80S AREAWIDE
AND EVEN SOME LOWER ELEVATION SPOTS NEAR 90. ANOTHER MUGGY NIGHT
TONIGHT WITH LOWS IN THE MID TO UPPER 60S.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
350 AM UPDATE...
LEFTOVERS OF UPPER LOW NOW OVER KY/TN BORDER...WILL DRIFT
NORTHWARD AROUND COLLAPSING UPPER RIDGE...AND CARRY THROUGH OUR
REGION MONDAY. DESPITE THAT LITTLE BIT OF ENERGY...PRECIPITABLE
WATER VALUES WILL ACTUALLY BE LOWERING THROUGH THE DAY. DIURNAL
HEATING AND MODEST INSTABILITY MOSTLY LESS THAN 1000 J/KG SHOULD
ALLOW FOR SCATTERED SHOWERS AND THUNDERSTORMS...WITH BEST CHANCES
GENERALLY FROM CENTRAL SOUTHERN TIER OF NY TO NEPA /THOUGH AT
LEAST SOME CHANCE AREAWIDE/.
COME TUESDAY...PRECIPITABLE WATER VALUES LOOK TO RETURN ABOVE 1.5
INCHES AND WE WILL ALSO AGAIN BE PENETRATED BY THE BELT OF
WESTERLIES AND EMBEDDED WAVES. UNCERTAINTY ON TIMING OF WAVES AND
MESOSCALE INFLUENCES PREVENTED ME FROM GOING HIGHER THAN 40-50 PCT
POPS...BUT AT LEAST SCATTERED DIURNALLY-DRIVEN CONVECTION LOOKS
LIKE A FAIR BET.
BOTH MONDAY AND TUESDAY...DAYTIME TEMPERATURES WILL REMAIN
ROUGHLY 6 TO 9 DEGREES ABOVE CLIMATOLOGY. DEWPOINTS IN ABOUT THE
MID 60S MONDAY WILL SNEAK MORE INTO THE UPPER 60S TUESDAY...ALLOWING
HEAT INDICES TO ECLIPSE 90 AT LOWER ELEVATIONS. DESPITE THE HEAT AND
HUMIDITY...CAPES FAIRLY MODEST AND CONVECTIVE PARAMETERS SUCH AS
SHEAR ARE ONLY MARGINAL AT BEST...THUS OPPORTUNITY FOR AN
ORGANIZED SEVERE THREAT APPEARS QUITE LOW.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
A FLAT RIDGE WILL EXIST OVER MUCH OF THE EASTERN CONUS THIS
PERIOD. IMPULSES WILL ROTATE OVER THE TOP OF THE RIDGE, WHILE
WARM/MOIST AIR WILL REMAIN IN PLACE ACROSS NY/PA TYPIFIED BY 850MB
TEMPS OF 16C TO 20C.
THE RESULT WILL BE A MILD TEMPERATURE PATTERN, WITH THE DAILY
THREAT FOR ISOLATED TO SCATTERED THUNDERSTORMS. THE BEST CHANCE
FOR THUNDERSTORMS WILL BE ON THURSDAY, WHEN A TROF OVER SOUTHERN
CANADA DIPS ACROSS THE GREAT LAKES TOWARD LAKE ONTARIO.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
ATMOSPHERE WILL DESTABILIZE THIS AFTERNOON WITH CAPES PROJECTED AT
1000-2000 J/KG. A WEAK WAVE WILL DRIFT ACROSS THE REGION,
INCREASING THE POTENTIAL FOR THUNDERSTORM DEVELOPMENT. LATEST HRRR
CONCURS, BRINGING A LINE OF CONVECTION THROUGH CENTRAL NY BETWEEN
18Z AND 22Z.
WITH INCREASED CONFIDENCE FOR AFTERNOON CONVECTION...TAFS WILL NOW
INCLUDE TEMPO GROUPS FOR THUNDER AT THE NY TERMINALS.
OUTLOOK...MON 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...MDP
NEAR TERM...CMG/MDP
SHORT TERM...MDP
LONG TERM...DJP
AVIATION...DJP
AREA FORECAST DISCUSSION
NWS RALEIGH NC
700 AM EDT SUN JUN 23 2013
.SYNOPSIS...
WEAK LOW PRESSURE OVER EASTERN NORTH CAROLINA WILL GRADUALLY
DISSIPATE TODAY. A SURFACE TROUGH WILL LINGER OVER THE PIEDMONT
THROUGH MID WEEK... AS A WARM AND MOIST AIR MASS HOLDS OVER THE
REGION.
&&
.NEAR TERM /THROUGH MONDAY NIGHT/...
AS OF 300 AM SUNDAY...
THE WAVE OF LOW PRESSURE THAT MOVED THROUGH EASTERN NC LAST EVENING
IS NOW MOVING INTO SOUTH CENTRAL VA...AND THE BULK OF HEAVY RAIN ON
ITS EASTERN FLANK IS EXITING THE NORTHERN COASTAL PLAIN. IN ITS
WAKE...A WEAK BOUNDARY LINGERS NEAR THE I-95 CORRIDOR...WHERE A FEW
SHOWERS AND THUNDER STORMS CONTINUE TO DEVELOP. HRRR SIM
REFLECTIVITY SUGGEST PRECIP WILL EVENTUALLY SHIFT NORTHWESTWARD INTO
THE PIEDMONT THIS MORNING AS AN UPPER LEVEL LOW OVER THE TN VALLEY
LIFTS ALONG THE APPALACHIANS. AS THE DAY WEARS ON...A BROAD
SOUTH-SOUTHEASTERLY LOW LEVEL FLOW WILL DOMINATE AS THE BERMUDA HIGH
BECOMES ESTABLISHED. MOISTURE CONVERGENCE IN THE VICINITY OF THE
WEAK BOUNDARY SHOULD BE THE MAIN FOCUS FOR WHAT WILL OTHERWISE BE
SCATTERED SHOWERS AND STORMS IN AN ENVIRONMENT CHARACTERIZED BY PW
AROUND 1.8 INCHES AND MLCAPE OF 500-1000 J/KG. HIGHS SHOULD REACH
THE MID 80S UNDER PARTLY TO MOSTLY CLOUDY SKIES.
TONIGHT...
A FEW SHOWERS MAY LINGER INTO THE EVENING HOURS...BUT CONVECTION
SHOULD BE MOSTLY DIURNAL IN NATURES. LOW CLOUDS ARE EXPECTED ONCE
AGAIN OVERNIGHT AND LOWS WILL FALL ONLY INTO THE UPPER 60S.
MONDAY AND MONDAY NIGHT...
MOIST SOUTHERLY FLOW WILL CONTINUE ON MONDAY WITH UPPER LEVEL
HEIGHTS SLOWLY BUILDING OVER THE WESTERN ATLANTIC AND
WEST-SOUTHWESTERLY FLOW ALOFT OVER NC. A WEAK LEE TROUGH WILL BEGIN
TO DEVELOP OVER THE PIEDMONT...BUT ITS NOT APPARENT HOW MUCH OF A
FOCUS THIS WILL BE FOR AFTERNOON CONVECTION.
THERMODYNAMICALLY...THE ATMOSPHERE WILL BE VERY SIMILARLY TO
SUNDAY...WITH WEAK LAPSE RATES AND MLCAPE POSSIBLY APPROACHING 1000
J/KG ACROSS THE SOUTH AND EAST. PW WILL REMAIN WELL ABOVE 1.5
INCHES...SUGGESTING SCATTERED SHOWERS AND STORMS WILL BE POSSIBLE.
HIGHS WILL BE A COUPLE DEGREES WARMER THAN SUNDAY AS THE UPPER RIDGE
BUILDS CLOSER TO THE COAST...85-89. LOWS MONDAY NIGHT IN THE UPPER
60S AND LOWER 70S.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 240 AM SUNDAY...
FOR TUESDAY/TUESDAY NIGHT: THE MID LEVEL ANTICYCLONE NOW CENTERED
OVER THE WRN ATLANTIC WILL HAVE EVOLVED INTO A WEAKER BUT MORE
EXPANSIVE RIDGE COVERING MUCH OF THE SOUTHERN HALF OF THE COUNTRY
(WEST COAST EXCEPTED) BY TUESDAY... RESULTING IN A WEAK WNW STEERING
FLOW OVER NC AND POOR DEEP LAYER SHEAR AS THE WESTERLIES RETREAT
WELL TO THE NORTH. MODERATE TO POTENTIALLY HIGH INSTABILITY IS
EXPECTED BY AFTERNOON WITH GFS-PROJECTED MLCAPE OF 2000-2800 J/KG
PARTICULARLY OVER THE EASTERN AND SOUTHERN PORTIONS OF CENTRAL NC...
SUPPORTIVE OF AT LEAST SCATTERED SHOWERS AND STORMS WITH DAYTIME
HEATING GIVEN PRECIP WATER VALUES OF 1.6-2.0 INCHES... 150-180
PERCENT OF NORMAL. AN MCV INDICATED BY THE MODELS OVER NEB EARLY
MONDAY MORNING IS EXPECTED TO TRACK ACROSS MI/IN/OH BY TUESDAY
MORNING BEFORE TRACKING ACROSS THE MID ATLANTIC REGION LATE
TUESDAY/TUESDAY NIGHT. THIS ADDED DYNAMIC FORCING FOR ASCENT FROM
DPVA (ALBEIT WEAK) COULD RESULT IN BETTER COVERAGE OF CONVECTION IN
AND NEAR AND EAST OF THE SURFACE LEE TROUGH LATE AFTERNOON THROUGH
THE EVENING. WILL GRADUALLY INCREASE POPS THROUGH THE AFTERNOON TO
40-50 PERCENT... CONTINUING AND SPREADING WEST TO EAST THROUGH THE
EVENING BEFORE TAPERING BACK DOWN TO SLIGHT CHANCES OVERNIGHT... AS
WE HANG ON TO A WARM MOIST AIR MASS AND AT LEAST MARGINAL
INSTABILITY. THICKNESSES SHOULD BE VERY CLOSE TO NORMAL...
INDICATIVE OF HIGHS 85-90 WITH SKIES VARYING BETWEEN PARTLY AND
MOSTLY CLOUDY. MILD LOWS OF 67-73 WITH INCREASING MID AND HIGH
CLOUDS OVERNIGHT AS THE MCV APPROACHES.
FOR WEDNESDAY/WEDNESDAY NIGHT: EXPECT A COUPLE OF SHOWERS AND AN
ISOLATED STORM OR TWO TO PERSIST INTO WEDNESDAY MORNING GIVEN THE
VERY MOIST (PW OF 1.5-1.9 IN.) AND SOMEWHAT UNSTABLE (MLCAPE OF
1000-1500 J/KG) ENVIRONMENT EVEN EARLY IN THE DAY... WITH THE
PERSISTENT LEE TROUGH EXTENDING THROUGH CENTRAL NC AND SUBTLE
WEAKNESS ALOFT OVER ERN NC. THE WEAK WIND FIELD AND LACK OF DISTINCT
SHARP FEATURES TO FOCUS CONVECTION RESULTS IN A FORECAST WITH HIGH
CONFIDENCE IN AT LEAST SCATTERED SHOWERS/STORMS BUT LITTLE
CONFIDENCE IN THE DETAILS OF EXACTLY WHO IS MOST LIKELY TO SEE RAIN
IN CENTRAL NC. PRECIP WATER REMAINS HIGH ANOMALOUSLY HIGH AND THE
GFS TRANSLATES THE STEADILY RISING THICKNESSES AND WARMING SURFACE
TEMPS TO GREATER INSTABILITY... 2200-3000 J/KG OF MLCAPE ESPECIALLY
FROM HIGHWAY 1 EAST. EXPECT ANOTHER ROUND OF GOOD CHANCE POPS
FOCUSED ON THE AFTERNOON AND EVENING... AND AS SHOULD BE THE CASE
TUESDAY... THE WEAK WIND FIELD WILL LEAD TO MEANDERING AND
UNORGANIZED MULTICELL CONVECTION. HIGHS 87-92 AND LOWS 69-73. -GIH
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 250 AM SUNDAY...
EVOLUTION TOWARD A MORE AMPLIFIED PATTERN OVER NOAM WILL OCCUR AS WE
HEAD INTO THE WEEKEND. A MID LEVEL ANTICYCLONE WILL STRENGTHEN OVER
THE FOUR CORNERS REGION IN RESPONSE TO A POWERFUL VORTEX OVER THE
NORTHEAST PACIFIC NEAR 47N/140W... WHICH EJECTS SHORTWAVE ENERGY
INTO CENTRAL CANADA AND A MID LEVEL JET ACROSS THE DAKOTAS. THE
RESULTING FALLING HEIGHTS OVER ONTARIO CULMINATE IN A CLOSED LOW
OVER MI OVER THE WEEKEND AND A TREND TOWARD DEEPENING LONGWAVE
TROUGHING OVER THE EASTERN HALF OF THE CONUS OVER THE WEEKEND.
PRECIP WATER SHOULD REMAIN ABOVE NORMAL THROUGH THE PERIOD WITH
SHARPENING OF THE SURFACE TROUGH THROUGH CENTRAL NC AND AN
INCREASING WNW MID LEVEL FLOW... FACILITATING GREATER ORGANIZATION
OF SHOWERS/STORMS AS WE HEAD INTO THE WEEKEND. GIVEN THIS IMPROVING
SHEAR AND LITTLE EXPECTED CHANGE IN THE MOISTURE AND THERMAL PROFILE
OVER THE AREA... WILL HOLD ONTO DAILY SCATTERED SHOWERS AND
STORMS... MAINLY AFTERNOON AND EVENING. LOW LEVEL THICKNESSES HOLD
SLIGHTLY ABOVE NORMAL... SO EXPECT HIGHS IN THE MID 80S TO AROUND
90. WARM LOWS IN THE UPPER 60S TO LOWER 70S. -GIH
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AS OF 700 AM SUNDAY...
CEILINGS AND VSBYS VARY WIDELY ACROSS CENTRAL NC...WITH PATCHY
LIFR/IFR CONDITIONS BEING REPORTED AMONG WHAT IS OTHERWISE VFR
CONDITIONS. STRATUS AFFECTING KFAY AND KRWI WILL LIFT AND
EVENTUALLY SCATTER OUT THIS MORNING...REACHING VFR BY 13-14Z.
SCATTERED SHOWERS AND STORMS WILL BE POSSIBLE THIS AFTERNOON...WITH
THE HIGHEST PROBABILITY FROM THE CENTRAL PIEDMONT TO THE COASTAL
PLAIN (KRDU/KFAY/KRWI )...WHERE A WEAK BOUNDARY LINGERS.
TONIGHT...
WITH HIGH PRESSURE OVER THE WESTERN ATLANTIC AND MOIST SOUTHERLY
FLOW ACROSS CENTRAL NC...THE PATTERN WOULD SUGGEST THE POTENTIAL FOR
STRATUS TO DEVELOP. FORECAST SOUNDINGS DO NOT INDICATE WIDESPREAD
STRATUS...BUT CROSS SECTIONS OF RELATIVE HUMIDITY SUGGEST VERY LOW
STRATUS AND/OR FOG WILL BE POSSIBLE.
OUTLOOK...
WARM AND MOIST SOUTHERLY FLOW AROUND A BERMUDA HIGH WILL BRING
UNSETTLED WEATHER FOR MUCH OF THE WEEKEND...WITH SUB-VFR CONDITIONS
POSSIBLE EACH MORNING AND SCATTERED SHOWERS/STORMS IN THE AFTERNOON
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...BLS
SHORT TERM...HARTFIELD
LONG TERM...HARTFIELD
AVIATION...BLS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1050 AM CDT SUN JUN 23 2013
.UPDATE...
ISSUED AT 1050 AM CDT SUN JUN 23 2013
MAIN UPDATES WERE TO MODIFY SKY COVER AND PRECIP/THUNDER CHANCES
BASED ON LATEST SATELLITE AND RADAR IMAGERY. TEMPERATURES WERE
TRENDED DOWN A TAD NORTH TO ACCOUNT FOR EXTENSIVE CLOUD
COVER...WHICH IS EXPECTED TO PERSIST INTO THE AFTERNOON HOURS
LIMITING DAYTIME HEATING.
THERE REMAINS A CHANCE FOR ISOLATED CONVECTION...SHOWERS OR WEAK
THUNDERSTORMS...OVER MUCH OF THE WEST AND CENTRAL THIS AFTERNOON WITH
THE UPPER TROUGH OVER NORTH DAKOTA ALONG WITH SOME INSTABILITY
STILL PRESENT.
UPDATE ISSUED AT 639 AM CDT SUN JUN 23 2013
THERE WERE MINOR UPDATES TO ACCOUNT FOR THE LATEST SATELLITE AND
RADAR IMAGERY TRENDS. CYCLONIC FLOW ALOFT WILL HELP ERODE THE CAP
THIS AFTERNOON TO RELEASE WEAK CONVECTIVE INSTABILITY IN THE FORM
OF WEAK THUNDERSTORMS...AS INDICATED BY THE LAST SEVERAL RUNS OF
THE HRRR MODEL.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 320 AM CDT SUN JUN 23 2013
THE HIGHLIGHT OF THE SHORT TERM ARE CONVECTIVE CHANCES FOR TODAY.
CURRENTLY...WIDESPREAD LIGHT TO MODERATE RAIN WITH EMBEDDED
THUNDERSTORMS CONTINUES ACROSS MOST OF NORTHERN NORTH DAKOTA IN
ASSOCIATION WITH THE RIGHT ENTRANCE REGION OF THE UPPER LEVEL JET
STREAK AHEAD OF THE STRONG SHORTWAVE. AS THIS WAVE CONTINUES TO
PROPAGATE TO THE NORTHEAST THROUGH THE MORNING AND AFTERNOON...THE
AREA OF MORE WIDESPREAD PRECIPITATION ACROSS NORTHERN NORTH DAKOTA
WILL BECOME FOCUSED INTO MANITOBA. HOWEVER...WITH CLEARING SKIES
EXPECT SURFACE DESTABILIZATION AND THE DEVELOPMENT OF DIURNALLY
DRIVEN SCATTERED SHOWERS AND THUNDERSTORMS AS DEPICTED BY THE 00
UTC 4KM WRF AND THE 06 UTC HRRR AREA WIDE. DO NOT ANTICIPATE
WIDESPREAD SEVERE THUNDERSTORMS...HOWEVER...ML CAPE VALUES NEAR
1000 J/KG AND DEEP LAYER SHEAR OF 30-35 KTS SUGGEST THE POTENTIAL
FOR MARGINAL SEVERE HAIL WITH THE STRONGER STORMS. CONVECTION IS
EXPECTED TO QUICKLY FADE WITH SUNSET...WITH FOG POSSIBLE WITH
CLEAR SKIES AND LIGHT WINDS IN A WEAK SURFACE RIDGE AXIS TONIGHT.
DID CANCEL THE FLASH FLOOD WATCH THAT WAS IN EFFECT FOR THE JAMES
RIVER VALLEY AND PORTIONS OF FAR SOUTH CENTRAL NORTH DAKOTA. WHILE
SCATTERED THUNDERSTORMS ARE POSSIBLE TODAY...THE THREAT FOR FLASH
FLOODING IS NO LONGER ANTICIPATED. SEE THE HYDROLOGY DISCUSSION
FOR DETAILS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 320 AM CDT SUN JUN 23 2013
THE MAIN FOCUS TODAY IS ON THE POTENTIAL FOR STRONG/SEVERE
THUNDERSTORMS MONDAY THROUGH TUESDAY NIGHT.
ANOTHER LOW PRESSURE SYSTEM IS SCHEDULED TO MOVE ACROSS THE NORTHERN
PLAINS TUESDAY AS THE FOUR CORNERS MID/UPPER LEVEL RIDGE AND
NORTHEASTERN PACIFIC MID/UPPER LEVEL TROUGH MAINTAIN A BELT OF
WESTERLIES ACROSS THE NORTHERN ROCKIES AND DAKOTAS. THE 00 UTC
NAM/ECMWF/GFS/GEM GLOBAL ALL AGREE ON GENERAL TIMING OF THE
SYSTEM...BUT THERE IS SIGNIFICANT SPREAD ON THE TIMING/LOCATION OF
ASSOCIATED CONVECTION. THE UNCERTAINTY ASSOCIATED WITH COMPLEX
MESOSCALE INTERACTIONS IS LARGE...SO THERE IS NO EASY WAY TO PICK
THE SINGLE MODEL SOLUTION MOST LIKELY TO VERIFY. THUS...FORECASTS
USED A CONSENSUS BLEND OF ALL AVAILABLE UTC MODELS/ENSEMBLES.
THE STORM PREDICTION CENTER FORECAST FROM THEIR OUTLOOKS CALLS
FOR LATE AFTERNOON CONVECTION ALONG THE MT/ND BORDER LOOKS TO FORM
AN MCS THAT PROPAGATES INTO THE CENTRAL PLAINS ON MONDAY NIGHT.
CONVECTION LOOKS TO REGENERATE OVER CENTRAL NORTH DAKOTA ON TUESDAY
FOR ANOTHER ROUND IN CENTRAL AND EASTERN COUNTIES.
THEREAFTER...00 UTC MODELS/ENSEMBLES GENERALLY AGREE ON A MORE
DIURNAL NATURE FOR THE ISOLATED CONVECTION THAT DOES INITIATE AMIDST
STRONGER RIDGING ALOFT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1050 AM CDT SUN JUN 23 2013
WILL MAINTAIN VCSH OR VCTS FOR KISN-KMOT-KBIS-KJMS THROUGH 00Z
EARLY THIS EVENING. MVFR CU DEVELOPING ACROSS THE SOUTHERN
TERMINALS AS SKIES CLEAR. MVFR ALSO AT KMOT NEAR AN UPPER LEVEL
LOW PRESSURE SYSTEM. SKIES WILL TREND VFR ALL LOCATIONS BY EARLY
THIS EVENING AND PERSIST THROUGH 12Z MONDAY.
&&
.HYDROLOGY...
ISSUED AT 320 AM CDT SUN JUN 23 2013
DID CANCEL THE FLASH FLOOD WATCH THAT WAS IN EFFECT FOR THE JAMES
RIVER VALLEY AND PORTIONS OF SOUTH CENTRAL NORTH DAKOTA. WHILE
SCATTERED THUNDERSTORMS ARE POSSIBLE TODAY...MUCH LOWER
PRECIPITABLE WATER VALUES AND LOWER CONVECTIVE COVERAGE NEGATES
THE FLASH FLOOD THREAT. HOWEVER...WILL HAVE TO MONITOR THESE AREAS
AGAIN MONDAY AND TUESDAY AS STRONG TO SEVERE THUNDERSTORMS ARE
POSSIBLE WITH THE RETURN OF DEEP MOISTURE.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...AYD
LONG TERM...SCHECK
AVIATION...NH
HYDROLOGY...AYD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1008 AM CDT SUN JUN 23 2013
.UPDATE...
ISSUED AT 1007 AM CDT SUN JUN 23 2013
MADE SOME ADJUSTMENTS TO POPS FOR CURRENT RADAR TRENDS. THE PRECIP
HAS LIFTED OUT OF OUR SOUTHERN COUNTIES AS DRY AIR HAS MOVED
IN...AND THAT AREA SHOULD SEE SOME CLEARING LATER ON TODAY.
FURTHER NORTH...THERE IS STILL A LOT OF MOISTURE CONVERGENCE AND
PRECIP REDEVELOPMENT ALONG THE NORTHERN END OF THE SFC TROUGH
AXIS/FRONTAL BOUNDARY FROM DEVILS LAKE TOWARDS MAYVILLE. MORE
SHOWERS AND STORMS HAVE DEVELOPED IN THE NORTHEASTERN COUNTIES
ALSO AND THINK THAT DEVELOPMENT SHOULD CONTINUE THROUGH MUCH OF
THE DAY AS THE MAIN UPPER LOW KICKS SLOWLY OUT. SEVERITY LATER ON
WILL DEPEND ON DESTABILIZATION...BUT WILL HAVE TO WATCH THE NORTH
FOR ANYTHING GOING UNDER THE MAIN UPPER LOW.
UPDATE ISSUED AT 655 AM CDT SUN JUN 23 2013
AN AREA OF SHOWERS AND EMBEDDED THUNDER CONTINUES TO MOVE SLOWLY
NORTH THIS MORNING. EXPECT A SLOW WEAKENING TREND FOR A FEW
HOURS...BEFORE ACTIVITY INCREASES LATER THIS MORNING AND EARLY
AFTERNOON. NO MAJOR CHANGES TO THE FORECAST WITH THIS UPDATE.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 345 AM CDT SUN JUN 23 2013
THE MAIN CHALLENGE THIS MORNING WILL BE SEVERE STORM THREAT TODAY
AND MORE STORMS POSSIBLE MON NIGHT AND TUE. MODELS ARE IN GOOD
OVERALL AGREEMENT...AND WILL FOLLOW THE HRRR INITIALLY THEN SIDE
WITH THE CONSISTENT GFS.
FOR TODAY...EXPECT AN MCS TO BE ONGOING THIS MORNING MOVING FROM
SW TO NE. THERE COULD BE LOCALLY HEAVY RAINFALL THIS MORNING IN
THE SOUTH...AND THIS AREA IS QUITE SATURATED SO WILL CONTINUE WITH
THE FLASH FLOOD WARNING UNTIL 12Z. THERE COULD BE A MORE ORGANIZED
SEVERE THREAT BY EARLY AFTERNOON MAINLY IN THE MN COUNTIES ALONG A
COLD FRONT...MLCAPE TO AROUND 2000 J/KG AND AMPLE DEEP LAYERED
SHEAR. THE MAIN THREATS SHOULD BE LARGE HAIL AND DAMAGING WINDS.
FOR TONIGHT...ANY CONVECTION SHOULD QUICKLY MOVE OUT OF THE
EASTERN AREAS DURING THE EVENING. DRIER AIR WILL ADVECT INTO THE
REGION WITH GENERAL LIGHT WINDS. WILL HAVE TO WATCH FOR PATCHY FOG
IN AREAS THAT GET RAIN...BUT FOR NOW WON/T MENTION WITH AREAL
COVERAGE NOT CERTAIN.
ON MONDAY...EXPECT A DRY AND WARM DAY WITH 850MB TEMPS WARMING TO
AROUND +18C. MOISTURE PROFILES WILL BEGIN TO INCREASE BY AFTERNOON
IN THE WEST AHEAD OF THE NEXT SHORTWAVE.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 345 AM CDT SUN JUN 23 2013
FOR MONDAY NIGHT AND TUE...THE THREAT FOR SHOWERS AND STORMS WILL
ONCE AGAIN INCREASE WITH SHORTWAVE ENERGY MOVING THROUGH GENERAL
SW FLOW ALOFT. TIMING STILL REMAINS A QUESTION...BUT THE SEVERE
THREAT COULD ALSO INCREASE AT LEAST IN THE WEST ON TUE...AND WILL
FEEL LIKE SUMMER WITH TEMPS ABOVE NORMAL AND PLENTY OF MOISTURE IN
PLACE.
FOR WEDNESDAY THROUGH SATURDAY...A LONG WAVE TROUGH AXIS DEVELOPS
OVER THE EASTERN PACIFIC AND THE EASTERN US WHILE A LONG WAVE
RIDGE DEVELOPS OVER THE NORTHERN ROCKIES AND INTO THE CANADIAN
ROCKIES. PATTERN BECOMES MORE NORTHWEST FLOW ALOFT WITH TIME.
ECMWF BEGINS THE PERIOD AS A FASTER SOLUTION THAN THE GFS. THE ECMWF
MAINTAINS A CONSISTENT FAST BIAS THROUGH THE PERIOD. THE ECMWF HAS
TRENDED WITH FASTER SOLUTIONS OVER THE LAST FEW MODEL RUNS WHILE
THE GFS HAS TRENDED SLOWER. WILL BLEND THE TWO MODELS AND WILL SPEED
UP PRECIPITATION A BIT FROM TODAYS RUN AND MAY KEEP YESTERDAYS RUN
WITH SOME TIME PERIODS.
LITTLE CHANGE TO TEMPS THIS PERIOD FROM YESTERDAYS RUN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 655 AM CDT SUN JUN 23 2013
AN AREA OF IFR CIGS/VSBY HAS DEVELOP NEAR BJI AND SHOULD SLOWLY
IMPROVE THIS MORNING. EXPECT AREAS OF SHOWERS AND A FEW STORMS
WITH WINDS SHIFTING TO THE WEST BY LATE MORNING/EARLY AFTERNOON
FROM WEST TO EAST BEHIND A COOL FRONT. DRIER AIR WILL ADVECT INTO
THE REGION BY LATER THIS AFTERNOON AND PRECIP SHOULD END ALONG
WITH VFR CONDITIONS IN ALL AREAS BY LATE AFTERNOON/EARLY EVENING.
&&
.HYDROLOGY...
ISSUED AT 345 AM CDT SUN JUN 23 2013
RIVER RISES CONTINUE IN THE SOUTHERN VALLEY AND WAHPETON IS
NEARING A CREST NEAR MODERATE FLOOD STAGE. ADDITIONAL HEAVY
RAINFALL IS OCCURRING ACROSS PORTIONS OF THE SOUTHERN BASIN THIS
MORNING...AND ADDITIONAL LOCAL RISES WILL NEED TO BE MONITORED
TODAY ALONG WITH ADDITIONAL HEAVY RAINFALL.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...DK
LONG TERM...HOPPES/DK
AVIATION...DK
HYDROLOGY...DK
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
653 AM CDT SUN JUN 23 2013
.UPDATE...
ISSUED AT 655 AM CDT SUN JUN 23 2013
AN AREA OF SHOWERS AND EMBEDDED THUNDER CONTINUES TO MOVE SLOWLY
NORTH THIS MORNING. EXPECT A SLOW WEAKENING TREND FOR A FEW
HOURS...BEFORE ACTIVITY INCREASES LATER THIS MORNING AND EARLY
AFTERNOON. NO MAJOR CHANGES TO THE FORECAST WITH THIS UPDATE.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 345 AM CDT SUN JUN 23 2013
THE MAIN CHALLENGE THIS MORNING WILL BE SEVERE STORM THREAT TODAY
AND MORE STORMS POSSIBLE MON NIGHT AND TUE. MODELS ARE IN GOOD
OVERALL AGREEMENT...AND WILL FOLLOW THE HRRR INITIALLY THEN SIDE
WITH THE CONSISTENT GFS.
FOR TODAY...EXPECT AN MCS TO BE ONGOING THIS MORNING MOVING FROM
SW TO NE. THERE COULD BE LOCALLY HEAVY RAINFALL THIS MORNING IN
THE SOUTH...AND THIS AREA IS QUITE SATURATED SO WILL CONTINUE WITH
THE FLASH FLOOD WARNING UNTIL 12Z. THERE COULD BE A MORE ORGANIZED
SEVERE THREAT BY EARLY AFTERNOON MAINLY IN THE MN COUNTIES ALONG A
COLD FRONT...MLCAPE TO AROUND 2000 J/KG AND AMPLE DEEP LAYERED
SHEAR. THE MAIN THREATS SHOULD BE LARGE HAIL AND DAMAGING WINDS.
FOR TONIGHT...ANY CONVECTION SHOULD QUICKLY MOVE OUT OF THE
EASTERN AREAS DURING THE EVENING. DRIER AIR WILL ADVECT INTO THE
REGION WITH GENERAL LIGHT WINDS. WILL HAVE TO WATCH FOR PATCHY FOG
IN AREAS THAT GET RAIN...BUT FOR NOW WON/T MENTION WITH AREAL
COVERAGE NOT CERTAIN.
ON MONDAY...EXPECT A DRY AND WARM DAY WITH 850MB TEMPS WARMING TO
AROUND +18C. MOISTURE PROFILES WILL BEGIN TO INCREASE BY AFTERNOON
IN THE WEST AHEAD OF THE NEXT SHORTWAVE.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 345 AM CDT SUN JUN 23 2013
FOR MONDAY NIGHT AND TUE...THE THREAT FOR SHOWERS AND STORMS WILL
ONCE AGAIN INCREASE WITH SHORTWAVE ENERGY MOVING THROUGH GENERAL
SW FLOW ALOFT. TIMING STILL REMAINS A QUESTION...BUT THE SEVERE
THREAT COULD ALSO INCREASE AT LEAST IN THE WEST ON TUE...AND WILL
FEEL LIKE SUMMER WITH TEMPS ABOVE NORMAL AND PLENTY OF MOISTURE IN
PLACE.
FOR WEDNESDAY THROUGH SATURDAY...A LONG WAVE TROUGH AXIS DEVELOPS
OVER THE EASTERN PACIFIC AND THE EASTERN US WHILE A LONG WAVE
RIDGE DEVELOPS OVER THE NORTHERN ROCKIES AND INTO THE CANADIAN
ROCKIES. PATTERN BECOMES MORE NORTHWEST FLOW ALOFT WITH TIME.
ECMWF BEGINS THE PERIOD AS A FASTER SOLUTION THAN THE GFS. THE ECMWF
MAINTAINS A CONSISTENT FAST BIAS THROUGH THE PERIOD. THE ECMWF HAS
TRENDED WITH FASTER SOLUTIONS OVER THE LAST FEW MODEL RUNS WHILE
THE GFS HAS TRENDED SLOWER. WILL BLEND THE TWO MODELS AND WILL SPEED
UP PRECIPITATION A BIT FROM TODAYS RUN AND MAY KEEP YESTERDAYS RUN
WITH SOME TIME PERIODS.
LITTLE CHANGE TO TEMPS THIS PERIOD FROM YESTERDAYS RUN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 655 AM CDT SUN JUN 23 2013
AN AREA OF IFR CIGS/VSBY HAS DEVELOP NEAR BJI AND SHOULD SLOWLY
IMPROVE THIS MORNING. EXPECT AREAS OF SHOWERS AND A FEW STORMS
WITH WINDS SHIFTING TO THE WEST BY LATE MORNING/EARLY AFTERNOON
FROM WEST TO EAST BEHIND A COOL FRONT. DRIER AIR WILL ADVECT INTO
THE REGION BY LATER THIS AFTERNOON AND PRECIP SHOULD END ALONG
WITH VFR CONDITIONS IN ALL AREAS BY LATE AFTERNOON/EARLY EVENING.
&&
.HYDROLOGY...
ISSUED AT 345 AM CDT SUN JUN 23 2013
RIVER RISES CONTINUE IN THE SOUTHERN VALLEY AND WAHPETON IS
NEARING A CREST NEAR MODERATE FLOOD STAGE. ADDITIONAL HEAVY
RAINFALL IS OCCURRING ACROSS PORTIONS OF THE SOUTHERN BASIN THIS
MORNING...AND ADDITIONAL LOCAL RISES WILL NEED TO BE MONITORED
TODAY ALONG WITH ADDITIONAL HEAVY RAINFALL.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...DK
SHORT TERM...DK
LONG TERM...HOPPES/DK
AVIATION...DK
HYDROLOGY...DK
AREA FORECAST DISCUSSION
NWS BISMARCK ND
643 AM CDT SUN JUN 23 2013
.UPDATE...
ISSUED AT 639 AM CDT SUN JUN 23 2013
THERE WERE MINOR UPDATES TO ACCOUNT FOR THE LATEST SATELLITE AND
RADAR IMAGERY TRENDS. CYCLONIC FLOW ALOFT WILL HELP ERODE THE CAP
THIS AFTERNOON TO RELEASE WEAK CONVECTIVE INSTABILITY IN THE FORM
OF WEAK THUNDERSTORMS...AS INDICATED BY THE LAST SEVERAL RUNS OF
THE HRRR MODEL.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 320 AM CDT SUN JUN 23 2013
THE HIGHLIGHT OF THE SHORT TERM ARE CONVECTIVE CHANCES FOR TODAY.
CURRENTLY...WIDESPREAD LIGHT TO MODERATE RAIN WITH EMBEDDED
THUNDERSTORMS CONTINUES ACROSS MOST OF NORTHERN NORTH DAKOTA IN
ASSOCIATION WITH THE RIGHT ENTRANCE REGION OF THE UPPER LEVEL JET
STREAK AHEAD OF THE STRONG SHORTWAVE. AS THIS WAVE CONTINUES TO
PROPAGATE TO THE NORTHEAST THROUGH THE MORNING AND AFTERNOON...THE
AREA OF MORE WIDESPREAD PRECIPITATION ACROSS NORTHERN NORTH DAKOTA
WILL BECOME FOCUSED INTO MANITOBA. HOWEVER...WITH CLEARING SKIES
EXPECT SURFACE DESTABILIZATION AND THE DEVELOPMENT OF DIURNALLY
DRIVEN SCATTERED SHOWERS AND THUNDERSTORMS AS DEPICTED BY THE 00
UTC 4KM WRF AND THE 06 UTC HRRR AREA WIDE. DO NOT ANTICIPATE
WIDESPREAD SEVERE THUNDERSTORMS...HOWEVER...ML CAPE VALUES NEAR
1000 J/KG AND DEEP LAYER SHEAR OF 30-35 KTS SUGGEST THE POTENTIAL
FOR MARGINAL SEVERE HAIL WITH THE STRONGER STORMS. CONVECTION IS
EXPECTED TO QUICKLY FADE WITH SUNSET...WITH FOG POSSIBLE WITH
CLEAR SKIES AND LIGHT WINDS IN A WEAK SURFACE RIDGE AXIS TONIGHT.
DID CANCEL THE FLASH FLOOD WATCH THAT WAS IN EFFECT FOR THE JAMES
RIVER VALLEY AND PORTIONS OF FAR SOUTH CENTRAL NORTH DAKOTA. WHILE
SCATTERED THUNDERSTORMS ARE POSSIBLE TODAY...THE THREAT FOR FLASH
FLOODING IS NO LONGER ANTICIPATED. SEE THE HYDROLOGY DISCUSSION
FOR DETAILS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 320 AM CDT SUN JUN 23 2013
THE MAIN FOCUS TODAY IS ON THE POTENTIAL FOR STRONG/SEVERE
THUNDERSTORMS MONDAY THROUGH TUESDAY NIGHT.
ANOTHER LOW PRESSURE SYSTEM IS SCHEDULED TO MOVE ACROSS THE NORTHERN
PLAINS TUESDAY AS THE FOUR CORNERS MID/UPPER LEVEL RIDGE AND
NORTHEASTERN PACIFIC MID/UPPER LEVEL TROUGH MAINTAIN A BELT OF
WESTERLIES ACROSS THE NORTHERN ROCKIES AND DAKOTAS. THE 00 UTC
NAM/ECMWF/GFS/GEM GLOBAL ALL AGREE ON GENERAL TIMING OF THE
SYSTEM...BUT THERE IS SIGNIFICANT SPREAD ON THE TIMING/LOCATION OF
ASSOCIATED CONVECTION. THE UNCERTAINTY ASSOCIATED WITH COMPLEX
MESOSCALE INTERACTIONS IS LARGE...SO THERE IS NO EASY WAY TO PICK
THE SINGLE MODEL SOLUTION MOST LIKELY TO VERIFY. THUS...FORECASTS
USED A CONSENSUS BLEND OF ALL AVAILABLE UTC MODELS/ENSEMBLES.
THE STORM PREDICTION CENTER FORECAST FROM THEIR OUTLOOKS CALLS
FOR LATE AFTERNOON CONVECTION ALONG THE MT/ND BORDER LOOKS TO FORM
AN MCS THAT PROPAGATES INTO THE CENTRAL PLAINS ON MONDAY NIGHT.
CONVECTION LOOKS TO REGENERATE OVER CENTRAL NORTH DAKOTA ON TUESDAY
FOR ANOTHER ROUND IN CENTRAL AND EASTERN COUNTIES.
THEREAFTER...00 UTC MODELS/ENSEMBLES GENERALLY AGREE ON A MORE
DIURNAL NATURE FOR THE ISOLATED CONVECTION THAT DOES INITIATE AMIDST
STRONGER RIDGING ALOFT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 639 AM CDT SUN JUN 23 2013
LIGHT TO MODERATE RAIN WITH EMBEDDED THUNDERSTORMS WILL CONTINUE
AT KISN AND KMOT THIS MORNING...WITH ACTIVITY BECOMING SCATTERED
ACROSS ALL OF WESTERN AND CENTRAL NORTH DAKOTA THROUGH THE
AFTERNOON. GIVEN THE NEAR SATURATED SURFACE OBSERVATIONS THIS
MORNING...POCKETS OF MVFR/IFR FOG AND STRATUS ARE POSSIBLE THROUGH
15 UTC.
&&
.HYDROLOGY...
ISSUED AT 320 AM CDT SUN JUN 23 2013
DID CANCEL THE FLASH FLOOD WATCH THAT WAS IN EFFECT FOR THE JAMES
RIVER VALLEY AND PORTIONS OF SOUTH CENTRAL NORTH DAKOTA. WHILE
SCATTERED THUNDERSTORMS ARE POSSIBLE TODAY...MUCH LOWER
PRECIPITABLE WATER VALUES AND LOWER CONVECTIVE COVERAGE NEGATES
THE FLASH FLOOD THREAT. HOWEVER...WILL HAVE TO MONITOR THESE AREAS
AGAIN MONDAY AND TUESDAY AS STRONG TO SEVERE THUNDERSTORMS ARE
POSSIBLE WITH THE RETURN OF DEEP MOISTURE.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SCHECK
SHORT TERM...AYD
LONG TERM...SCHECK
AVIATION...AYD
HYDROLOGY...AYD
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1036 AM CDT SUN JUN 23 2013
.UPDATE...CELLS ARE ALREADY POPPING UP ALONG THE CUMBERLAND
PLATEAU, WHERE SURFACE HUMIDITIES ARE HIGHEST. HRRR APPEARS TO
HAVE A GOOD HANDLE ON THE CURRENT ACTIVITY, AND IT SUGGESTS
NOTHING MORE THAN ISOLATED CONVECTION FOR THE REMAINDER OF MIDDLE
TENNESSEE FOR THE AFTERNOON. SO WILL GO AHEAD AN INCREASE POP`S
ALONG THE PLATEAU FOR THE REST OF TODAY AND LEAVE ISOLATED IN FOR
EVERYONE ELSE.
&&
.PREV DISCUSSION... /ISSUED 627 AM CDT SUN JUN 23 2013/
AVIATION...
AFTER LOCAL 4SM BR DISSIPATES EXPECT VFR CONDITIONS AT ALL THREE
TAF SITES THROUGH THE TAF PERIOD...UNLESS IMPACTED BY A STRONG
STORM THEN MVFR VIS MAY BE RESULT IN A BRIEF DOWNPOUR. EXPECT
THE DIURNLAL CU THAT HAS BEEN IMPACTING MIDDLE TENNESSEE OVER THE
LAST FEW DAYS TO REDEVELOP AGAIN TODAY AFTER 16Z THIS MORNING...THEN
DISSIPATE SOMETIME AFTER 00Z. ISOLATED CHANCES AT BEST FOR STRONG
STORMS.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
ROSE
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1048 AM CDT SUN JUN 23 2013
.UPDATE...NO CHANGES PLANNED TO FFA AT THIS TIME. SURFACE/UPPER
LOW LIFTING NORTH FROM NORTH DAKOTA. MEANWHILE CONVECTION ACROSS
IA HAS SHOWN A WEAKENING TREND...ESPECIALLY IN NRN IA. PLENTY OF
INSTABILITY IN THE CLEAR AIR ACROSS SRN WI. HRRR SUGGESTS ACTIVITY
INCREASES A BIT ON OUTFLOW AHEAD OF THE WEAKENING CONVECTIVE
SYSTEM AS IT HEADS INTO WI EARLY/MID AFTERNOON. 850 JET LIFTS
NORTH DURING THE AFTERNOON WITH BETTER 500 FORCING ALSO TO OUR
NORTHWEST. SO WILL RELAY ON LOW LEVEL OUTFLOW OR CONVECTIVE
INDUCED VORT MAX FOR FORCING MECHANISM THIS AFTERNOON. ARRIVAL OF
SOUTHWEST 850 JET TONIGHT RENEWS THREAT FOR ADDITIONAL CONVECTIVE
DEVELOPMENT AND FLASH FLOOD THREAT.
PC
&&
.AVIATION/18Z TAFS/...ONGOING CONVECTION ACRS IA SHOWING
WEAKENING. HOWEVER AIRMASS ACROSS SRN WI UNSTABLE. POTENTIAL FOR
ONGOING PRECIP BAND TO REINTENSIFY OR AS MESO MODELS
SUGGEST...DEVELOPMENT ALONG OUTFLOW BOUNDARY THIS AFTERNOON.
ADDITIONAL TSRA LIKELY OVERNIGHT AS 850 LOW LEVEL JET BECOMES BETTER
ORIENTED TOWARDS SRN WI.
PC
&&
.PREV DISCUSSION... /ISSUED 321 AM CDT SUN JUN 23 2013/
SHORT TERM...
TODAY AND TONIGHT...FORECAST CONFIDENCE MEDIUM.
HIGH RESOLUTION MODELS HAVE HAD A GOOD HANDLE ON THE RAPID DECAY OF
MCS OVERNIGHT. ONE ACTIVE AREA OF STORMS MOVING ALONG THE
MISSISSIPPI RIVER TOWARD SOUTHWEST WISCONSIN BUT EVEN THIS HAS SHOWN
DOWNWARD TREND AND SHOULD BE GONE BEFORE 12Z.
OUTFLOW BOUNDARY PUSHED SOUTH INTO NORTHERN ILLINOIS AND WE MAY HAVE
AN ISSUE AGAIN WITH HIGH TEMPERATURES DUE TO DEBRIS CLOUDS AND LOW
LEVEL COLD POOL. BUT THERE SHOULD BE MORE SUN AND WARMER HIGHS AND
TDS AROUND 70F SHOULD MAKE IT FEEL PRETTY MUGGY.
LOW LEVEL JET WEAKENS AND SHIFTS WEST FOR A TIME TODAY SO IT LOOKS
LIKE A PRETTY QUIET MORNING AND EARLY AFTERNOON. BOTH GFS AND NAM
HAVE A DRY POCKET MOVING ACROSS SOUTHERN WISCONSIN TODAY AND THERE
IS SUBTLE EVIDENCE OF THAT ON SATELLITE CURRENTLY.
THEN LOW LEVEL POSITIVE THETA-E ADVECTION KICKS IN LATE THIS
AFTERNOON IN THE WEST AND TONIGHT ACROSS MOST OF THE AREA AS SHORT
WAVE TROUGH BRUSHES AREA TO THE NORTH AND LOW LEVEL JET LEANS OVER
AGAIN. PATTERN OF WEAK UPPER TROUGHS TOPPING RIDGE AXIS WITH AN
EAST-WEST OUTFLOW BOUNDARY TO FOCUS CONVECTION HAS THIS LOOKING MUCH
LIKE SERIES OF MADDOX MESOHIGH TYPE FLASH FLOOD EVENTS.
NAM AND GFS SHOW PRECIPITABLE WATER INCREASING TO 150-175% OF NORMAL
WITH VALUES OF 1.7 TO 2.0". CORFIDI VECTORS HAVE THE OMINOUS LIGHT
AND VARIABLE LOOK AS THEY HAVE PAST COUPLE OF DAYS SO HEAVY RAIN
THREAT SEEMS TO CONTINUE.
ALTHOUGH THE MODELS HAVE THE LOOK OF A FAST MOVING LINE OF
STORMS...WIDESPREAD 4-8" RAINFALL OVER THE WEST THE PAST COUPLE OF
DAYS AND ONGOING FLOODING CALLS FOR A FLASH FLOOD WATCH FROM THIS
AFTERNOON INTO TONIGHT. PER COORDINATION WITH ARX AND DVN WILL
START THIS IN THE MIDDLE AFTERNOON AND THEN RUN IT THROUGH TONIGHT
AND MONDAY AS THE BOUNDARY STALLS AND THE LOW LEVEL JET SITS OVER
THE AREA WITH HIGH MOISTURE AND INSTABILITY.
ADJUSTED THE QPF UP A BIT TONIGHT AND MONDAY ABOVE GUIDANCE IN THE
WESTERN HALF THOUGH CONFIDENCE ON WHERE TO PUT HIGHEST AMOUNTS AND
HOW HIGH TO GO BUT LOCALLY 1-2" PER 12 HOURS SEEMS PLAUSIBLE. WITH
1 HOUR FFG ONLY 1 TO 1.5" IN THE WEST WE WILL REMAIN VULNERABLE FOR
SEVERAL DAYS TO FLASH FLOODING IN THE HILLY TERRAIN OF SOUTH CENTRAL
WISCONSIN.
MONDAY THROUGH TUESDAY NIGHT...FORECAST CONFIDENCE MEDIUM.
CONVECTION POTENTIAL AND MODEL TIMING/FEATURE DIFFERENCES CONTRIBUTE
TO THE UNCERTAINTY THIS FCST PERIOD. MODELS GENERALLY FORECAST A
SHORT WAVE TROUGH AND VORT MAX TO BEGIN TRAVERSING THE CWA MONDAY
AFTERNOON. THE THERMODYNAMIC ENVIRONMENT WILL BE ON ITS WAY TO
BEING PRIMED AS SEEN BY STEEPENING MID-LEVEL LAPSE RATES AND
SYNOPTIC ASCENT THAT IS PRESENT WITH Q-VECTOR DIVG AND LOW-LEVEL
WAA OCCURRING.
HOWEVER...THE PRIMARY CONCERN LOOKS TO BE TIED TO THE PRESENCE OF OR
LACK OF LIFT/FOCUS...BE IT A RESIDUAL OUTFLOW BOUNDARY OR SFC
BOUNDARY. OTHERWISE AMPLE INSTABILITY IN EITHER MEAN LAYER OR MOST
UNSTABLE CAPE WILL COMBINE WITH SUFFICIENT MOISTURE...WITH SFC DEW
POINTS FCST IN THE UPPER 60S-LOW 70S. DEEP LAYER 0-6 KM SHEAR
COULD BE THE LIMITING FACTOR WITH ANY DEVELOPMENT MONDAY BUT IT
DOES BEGIN TO INCREASE AFTER 0Z TUESDAY...THOUGH MODEL DIFFERENCES
EXIST HERE AS WELL. LLJ AT THIS TIME EXPECTED TO BE FOCUSED ON
SOUTHWEST IOWA. FOR POPS/WX WENT WITH A CONSENSUS APPROACH GIVEN
THE MODEL DIFFERENCES AND CONVECTION UNCERTAINTY.
HEAVY RAIN COULD BE A CONCERN GIVEN PRECIPITABLE WATER VALUES ARE
AROUND 150 PERCENT OF NORMAL/AT 1.5-1.8 INCHES AND CORFIDI VECTORS
EXHIBIT SLOW MOTIONS. ESPECIALLY IF THE HARDER HIT AREAS IN THE
WESTERN HALF OF THE CWA SEE ADDITIONAL HEAVY RAINFALL.
925 HPA TEMPERATURES HAVE A BIT OF A SPREAD MONDAY WITH THE
ECMWF COOLER THAN THE NAM/GFS. ALSO...WE HAVE BEEN A BIT WARM THE LAST
FEW FCST IN REGARD TO HIGHS...SO WENT WITH CONSENSUS GUIDANCE AND
STAYED AWAY FROM THE HIGHER INDIVIDUAL MODEL GUIDANCE.
LONG TERM...
WEDNESDAY THROUGH SATURDAY NIGHT...FORECAST CONFIDENCE MEDIUM.
WARM TEMPERATURES AND HUMID CONDITIONS CONTINUE INTO THURSDAY. AFTER
WHICH THE UPPER-LEVEL PATTERN CHANGES WITH A 500 HPA TROUGH
DEVELOPING OVER THE GREAT LAKES REGION AND A NORTHWEST FLOW TAKING OVER.
MODELS QUITE A BIT APART IN REGARD TO HOW THE PATTERN EVOLVES WITH
THE GFS DIGGING NOTABLY STRONGER. BEST CHANCES FOR PRECIP WED AND
OVERNIGHT WITH FRONTAL PASSAGE. SFC HIGH PRESSURE BEGINS TO BUILD
IN AT THE END OF THE TIME PERIOD.
AVIATION/12Z TAFS/...
OTHER THAN PESKY MVFR VISIBILITY DROPS IN LIGHT FOG EARLY THIS
MORNING AND AGAIN TONIGHT...GENERALLY VFR CONDITIONS OUTSIDE OF
THUNDERSTORMS. EXPECT MVFR AT KMSN TONIGHT WITH THUNDERSTORMS
AROUND BUT MUCH OF THE ACTIVITY COULD STAY WEST OF THE SOUTHEAST WI
TAFS TONIGHT AND ESPECIALLY BEFORE MIDNIGHT.
WITH ABOUT A 4 MB GRADIENT BETWEEN KGRB AND KUGN NOT EXPECTING MUCH
INLAND PENETRATION OF THE LAKE BREEZE THIS AFTERNOON BUT WILL BE A
CLOSE CALL AT KMKE IN THE 19-23Z PERIOD.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...FLASH FLOOD WATCH FROM 3 PM CDT THIS AFTERNOON THROUGH MONDAY
EVENING FOR WIZ046-047-056-057-062-063-067>069.
LM...NONE.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...CRAVEN
MONDAY THROUGH SATURDAY...ET
AREA FORECAST DISCUSSION
NWS PUEBLO CO
454 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 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 227 PM MDT SUN JUN 23 2013
VFR CONDITIONS AT ALL TERMINALS THROUGH THE NEXT 24 HOURS. WINDS
GUSTING 20 TO 25 KTS HAVE SPREAD ACROSS ALL TERMINALS. SMOKE IS
STARTING TO SPREAD EAST OVER THE SAN LUIS VALLEY...BUT THE LATE
START HAS KEPT THE DENSITY AND COVERAGE A BIT LESS AND DO NOT FORESEE
IT BEING AN ISSUE AT KPUB OR KCOS TONIGHT. AN ISOLATED THUNDERSTORM
IS POSSIBLE OVER THE PLAINS THIS EVENING...BUT NOT ANTICIPATING ANY
DEVELOPMENT AT OR NEAR THE TERMINALS. MOZLEY
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 11 AM TO 8 PM MDT MONDAY FOR COZ220>230.
RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ223>225.
FIRE WEATHER WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING
FOR COZ224-225.
&&
$$
UPDATE...MOZLEY
SHORT TERM...MOZLEY
LONG TERM...28
AVIATION...MOZLEY
AREA FORECAST DISCUSSION
NWS PUEBLO CO
251 PM MDT SUN JUN 23 2013
.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 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 227 PM MDT SUN JUN 23 2013
VFR CONDITIONS AT ALL TERMINALS THROUGH THE NEXT 24 HOURS. WINDS
GUSTING 20 TO 25 KTS HAVE SPREAD ACROSS ALL TERMINALS. SMOKE IS
STARTING TO SPREAD EAST OVER THE SAN LUIS VALLEY...BUT THE LATE
START HAS KEPT THE DENSITY AND COVERAGE A BIT LESS AND DO NOT FORESEE
IT BEING AN ISSUE AT KPUB OR KCOS TONIGHT. AN ISOLATED THUNDERSTORM
IS POSSIBLE OVER THE PLAINS THIS EVENING...BUT NOT ANTICIPATING ANY
DEVELOPMENT AT OR NEAR THE TERMINALS. MOZLEY
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 11 AM TO 8 PM MDT MONDAY FOR COZ220>230.
RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ223>225.
FIRE WEATHER WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING
FOR COZ224-225.
&&
$$
SHORT TERM...MOZLEY
LONG TERM...28
AVIATION...MOZLEY
AREA FORECAST DISCUSSION
NWS ALBANY NY
145 PM EDT SUN JUN 23 2013
.SYNOPSIS...
A WARM AND HUMID AIR MASS WILL CONTINUE THIS AFTERNOON THROUGH
THE MIDDLE OF NEXT WEEK. ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS WILL BE POSSIBLE IN THE AFTERNOON AND EARLY EVENING
THE NEXT FEW DAYS. SOME LOCALLY HEAVY RAINFALL WILL BE
POSSIBLE...AND PATCHY FOG WILL BE COMMON WITH MUGGY CONDITIONS
EACH NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 130 PM EDT...CONVECTION HAS INITIATED ALONG THE DIFFUSE
FRONTAL BOUNDARY ACROSS NORTHERN NY AND WESTWARD ALONG THE LAKE
BREEZE BOUNDARY AND INTO THE FINGER LAKES REGION. EXPERIMENTAL WRF
REFLECTIVITIES SUGGEST MORE UPSCALE GROWTH TO CONTINUE AS SBCAPES
PER LAPS/SPC-MESOSCALE WINDOW ARE CLOSE TO 3K J/KG. IN FACT...SPC
HAS INCREASED OUR PROBABILITIES INTO A SLIGHT RISK FOR SEVERE
WEATHER WITH THE RECENT SWOMCD HINTING AT THE POTENTIAL FOR A
WATCH. BEST SHEAR REMAINS MAINLY TO OUR NORTH AND MID LEVEL LAPSE
RATES REMAIN LESS THAN IDEAL FOR VIGOROUS UPDRAFTS...HOWEVER...WITH
DEWPOINTS NOW HOVERING NEAR 70F AND TEMPS NEAR 90F THE ENVIRONMENT
IS CONDUCIVE FOR CELLULAR STRUCTURES AND/OR SMALL BOWS ALONG THE
COLD POOL THAT IS GENERATED.
AS OF 1026 AM EDT...A DIFFUSE FRONTAL BOUNDARY CONTINUES TO BE
NORTH OF THE FORECAST AREA THIS MORNING. SOME SHOWERS AND
THUNDERSTORMS MOVED ACROSS THE SOUTHERN ADIRONDACKS EARLY THIS
MORNING...LEAVING UP TO AN INCH OF RAINFALL /ACCORDING TO RADAR
ESTIMATES/ IN SPOTS NEAR INDIAN LAKE.
THE FRONTAL BOUNDARY WILL CONTINUE TO LIFT NORTHWARD DURING THE
DAY...AS A SUBTROPICAL HIGH OFF THE MID ATLANTIC COAST AT THE
SFC...AND ALOFT CONTINUES TO FUNNEL HUMID AIR NORTHWARD. SFC
DEWPTS TODAY WILL RISE INTO THE MID AND U60S IN SOME LOCATIONS
WITH SOUTH TO SOUTHWEST SFC LAYER WINDS. H850 TEMPS INCREASE TO
+16 TO +17C WITH PARTLY TO MOSTLY SUNNY CONDITIONS. MAX TEMPS IN
THE M80S TO NEAR 90F WILL BE LIKELY IN THE VALLEYS WITH U70S TO
L80S OVER THE MTNS.
WEAK MID LEVEL VORTICES MOVING ALONG THE RIM OF THE UPPER LEVEL
RIDGE MAY TRIGGER SOME ISOLD-SCT THUNDERSTORMS TODAY. THE BEST 0-6
KM BULK SHEAR IS ACTUALLY JUST NORTH OF THE FCST AREA ACROSS NRN
NY AND NRN NEW ENGLAND WITH 20-30 KTS. MOST OF THE ALY FCST AREA
WILL BE IN A WEAK SHEAR ENVIRONMENT OF 10-20 KTS FOR PULSE OR VERY
LOOSELY ORGANIZED THUNDERSTORMS. FREEZING LEVELS WILL BE HIGH IN
THE 12-14 KFT AGL RANGE WITH WBZ HEIGHTS AROUND 11 KFT AGL.
SBCAPES WILL BE IN THE 500-1500 J/KG RANGE ACCORDING TO THE GFS.
NOT BUYING INTO THE NAM/S FAIRLY WIDESPREAD LOWER 70S DEWPT AIR OVER
THE REGION WITH SBCAPES OF 2000-3000 J/KG.
THE NEW 12Z NAM...AS WELL AS THE 12Z 3KM HRRR AND THE 12Z LOCAL
HIRES WRF SHOW CELLULAR CONVECTION POPPING UP ACROSS THE
ADIRONDACKS BY THE EARLY TO MID AFTN...AND MORE ACTIVITY
DEVELOPING AND MOVING ACROSS THE MOHAWK VALLEY...CAPITAL REGION
AND SRN VT...BY THE MID/LATE AFTN AND INTO THE EVENING HOURS. EACH
MODEL HAS THE PLACEMENT/TIMING SLIGHTLY DIFFERENT...BUT THE
CONVECTIVE MODE /CELLULAR PULSE TYPE STORMS/ SEEMS TO BE SIMILAR
IN EACH MODEL.
THIS MORNING/S 12Z KALY SOUNDING SHOWED A PWAT OF 1.62. AS A
RESULT...A MENTION OF HVY RAIN HAS BEEN INCLUDED WITH ISOLD-SCT
THUNDERSTORMS TODAY IN THE GRIDDED...TEXT FORECASTS...AND HWO
STATEMENT. AN ISOLD SEVERE MAY BE POSSIBLE TOO...ESPECIALLY IN
THE NRN ZONES...BUT THE FORECASTED WEAK MID LEVEL LAPSE RATES OF
LESS THAN 6 C/KM AND LIMITED AMOUNTS OF SHEAR IN THE 0-6 KM LAYER
SHOULD PROHIBIT WIDESPREAD STRONG CELLS. SPC MAINTAINS A /SEE
TEXT/ AREA ACROSS THE CENTRAL/NORTHERN PART OF THE CWA AND WE WILL
CONTINUE TO MONITOR MESOSCALE TRENDS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
TONIGHT...THE ISOLD TO SCT CONVECTION SHOULD SHRIVEL UP QUICKLY
BEFORE MIDNIGHT WITH THE LOSS OF THE DAYTIME HEATING. A PARTIAL
CLEARING WILL ALLOW PATCHY FOG JUST ABOUT ANYWHERE IN THE FCST
AREA WITH THE MOIST LOW LEVELS. IT HAS BEEN ADDED TO THE FORECAST
GRIDS. STICKY CONDITIONS WILL PREVAIL WITH LOWS IN THE MID AND
U60S IN THE VALLEYS...AND LOWER TO M60S OVER THE HILLS AND MTNS.
MONDAY...THE SULTRY CONDITIONS IN PLACE WILL PROMOTE INCREASED
CHANCES OF MORE PULSE THUNDERSTORMS WITH DEEP SHEAR VALUES LESS
THAN 15 KTS. SBCAPES WILL SOLIDLY BE IN THE 1000-2000 J/KG RANGE.
SOME THUNDERSTORMS MAY BE SLOW MOVERS OR LATCH TO THE TERRAIN FOR
A QUICK INCH OR TWO OF RAINFALL IN THE ANOMALOUSLY HIGH PWAT AIR
MASS. THE NAM SHOWS HINTS OF A SHORT-WAVE TROUGH IN THE W/SW ALOFT
MOVING THROUGH DURING THE AFTERNOON. THE ECMWF/GFS ALSO SHOW A
SUBTLE SHORT-WAVE TROUGH IN THE FLOW ALOFT. THE MID LEVEL LAPSE
RATES STEEPEN TO AROUND 6.5C/KM ON THE GFS. 850HPA THETA-E VALUES
INCREASE TO CLOSE TO 340K ACROSS PORTIONS CNTRL-ERN NY. THE
THETA-E RIDGE WEAKENS SLIGHTLY TOWARDS NIGHT FALL WITH THE PASSAGE
OF THIS TROUGH. HVY RAIN HAS BEEN INCLUDED WITH THE THUNDERSTORMS
AGAIN IN THE GRIDS/TEXT PRODUCTS. H850 TEMPS INCREASE CLOSE TO +17
TO +18C WITH THE GFSMOS TEMPS MUCH WARMER THAN THE METMOS TEMPS. A
BLEND WAS USED WITH A SHADING A LITTLE CLOSER TO THE GFSMOS VALUES
WITH SOUTHWEST TO WEST WINDS IN THE SFC TO BOUNDARY LAYER...TEMPS
MAY SPIKE UP A LITTLE BIT IN THE VALLEYS DUE TO DOWNSLOPING WITH
HIGHS IN THE U80S TO L90S WITH U70S TO M80S OVER THE HILLS AND
MTNS. APPARENT TEMPS COULD GET INTO M90S OR EVEN A FEW U90S IN THE
MID HUDSON VALLEY.
MONDAY NIGHT...SOME SUBSIDENCE OR DRYING ALOFT IN THE WAKE OF THE
TROUGH WILL ALLOW THE SKIES TO GO AT LEAST PARTLY
CLOUDY...ESPECIALLY THE NRN ZONES. PATCHY FOG WILL BE POSSIBLE
AGAIN WITH LOWS IN THE 60S.
TUE-TUE NIGHT...THE BROKEN RECORD FCST CONTINUES WITH DIURNAL
DRIVEN ISOLD-SCT SHOWERS AND THUNDERSTORMS AGAIN. INITIAL
CONVECTION WILL LIKELY BE FROM DIFFERENTIAL HEATING BTWN THE MTNS
AND VALLEYS...BUT POTENTIAL LAKE BREEZES OR WEAK SFC TROUGHS
UPSTREAM WILL HAVE TO BE MONITORED FOR MORE ORGANIZED CONVECTION.
STILL FAVORING THE GFS IN TERMS OF SHEAR AND INSTABILITY. SBCAPES
WILL LIKELY BE IN THE 1000-1500 J/KG RANGE WITH WEAKER MID LEVEL
LAPSE RATES COMPARED TO MONDAY. HIGHS WILL BE SIMILAR TO MON WITH
SOME L90S IN THE HUDSON RIVER VALLEY...AND WIDESPREAD 80S OVER THE
FCST AREA. MUGGY CONDITIONS WILL CONTINUE OVERNIGHT WITH MID AND
U60S IN THE VALLEYS...AND L60S OVER THE HIGH PEAKS.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
THE MODEL GUIDANCE AND ENSEMBLES ARE IN GOOD AGREEMENT WITH THE
LONGWAVE PATTERN AND CONTINUE TO INDICATE THE SUBTROPICAL RIDGE
SETTLES IN OVER THE SOUTHWESTERN UNITED STATES AND AMPLIFIES WITH
TROUGHING OVER THE GREAT LAKES REGION AND NORTHEAST INCREASING.
OVERALL THIS WILL RESULT IN THE WEATHER BECOMING MORE UNSETTLED
OVER THE NORTHEAST AS PIECES OF SHORT WAVE ENERGY MOVE THROUGH THE
TROUGH DEEPENING IT.
THE DIFFERENCES IN THE GUIDANCE LIES WITH THE TIMING OF INDIVIDUAL
SHORT WAVES AND THE MOVEMENT AND PLACEMENT OF BOUNDARIES. A WEAK
BACKDOOR FRONT IS EXPECTED TO MOVE SOUTHWARD INTO THE REGION MID
WEEK THEN RETURN BACK NORTHWARD AS A WARM FRONT LATE IN THE WEEK AS
THE TROUGH DEEPENS OVER THE REGION AND A LOW PRESSURE SYSTEM
APPROACHES. THE REGION IS EXPECTED TO BE IN THE WARM SECTOR OF THE
SYSTEM INTO THE WEEKEND WITH THE SYSTEM`S COLD FRONT EVENTUALLY
CROSSING THE REGION SATURDAY NIGHT/SUNDAY.
TEMPERATURES ARE EXPECTED TO RETURN TO MORE SEASONABLE LEVELS.
HOWEVER DEWPOINTS WILL REMAIN HIGH...IN THE 60S...MAKING FOR HUMID
CONDITIONS.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
WITH A VERY WARM AND MUGGY AIR MASS IN PLACE...SCATTERED SHOWERS AND
THUNDERSTORMS ARE DEVELOPING ACROSS NORTHERN AND WESTERN PORTIONS OF
THE REGION. THERE IS THE POTENTIAL FOR THESE TSRA TO AFFECT
KGFL/KALB/KPOU BY THE LATE AFTN OR EVENING HOURS...SO HAVE INCLUDED
A TEMPO FOR THOSE SITES. KPOU SHOULD REMAIN FAR ENOUGH TO THE SOUTH
AND CAPPED TO AVOID ANY TSTM ACTIVITY. WITHIN ANY TSTM...THERE IS
THE POSSIBILITY OF A QUICK BURST OF HVY RAINFALL AND A STRONG WIND
GUST AS WELL.
ANY TSTM ACTIVITY SHOULD DIMINISH AFTER EVENING WITH THE LOSS OF
HEATING. WITH THE HIGH DEWPOINTS AND LIGHT WINDS IN PLACE...SOME
FOG WILL DEVELOP TONIGHT...ESP IF ANY TERMINALS RECEIVE ANY
RAINFALL. THE SITES MOST LIKELY TO SEE IFR FOG WOULD BE
KGFL/KPSF...MAINLY AFTER MIDNIGHT.
ANY FOG WILL DISSIPATE SHORTLY AFTER SUNRISE ON MONDAY...ALLOWING
FOR VFR CONDITIONS TO RETURN TO ALL SITES FOR MONDAY MORNING.
OUTLOOK...
MON PM-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...MAINLY VFR. CHC -TSRA/-SHRA.
&&
.FIRE WEATHER...
A WARM AND HUMID AIR MASS WILL CONTINUE TODAY THROUGH
THE MIDDLE OF NEXT WEEK. ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS WILL BE POSSIBLE IN THE AFTERNOON AND EARLY EVENING
THE NEXT FEW DAYS.
RH LEVELS WILL REMAIN HIGH EACH NIGHT INTO THE MIDDLE OF NEXT WEEK
FOR THE FORMATION OF DEW ACROSS EASTERN NEW YORK AND WESTERN NEW
ENGLAND. NO FIRE WEATHER CONCERNS ARE EXPECTED AT THIS TIME.
&&
.HYDROLOGY...
FLOWS CONTINUE TO RECEDE TO LATE JUNE SEASONAL LEVELS. THE NEXT 5
DAYS WILL FEATURE ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS
WHICH WILL LIKELY NOT HAVE A SIGNIFICANT IMPACT ON THE MAIN STEM
RIVERS.
SLOW MOVING THUNDERSTORMS COULD PRODUCE A QUICK INCH OR TWO OF
RAINFALL WITH HIGHER THAN NORMAL PRECIPITABLE WATER VALUES OVER
THE HYDRO SERVICE AREA. SOME POOR DRAINAGE FLOODING OF LOW LYING
AREAS...AND PONDING OF WATER ON ROADWAYS WILL BE POSSIBLE ANY DAY
INTO THURSDAY. SOME SMALL STREAMS...CREEKS...AND BROOKS MAY REACH
BANKFULL QUICKLY IN THE HEAVY RAINFALL ASSOCIATED WITH THE
THUNDERSTORMS.
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...FRUGIS/WASULA
NEAR TERM...BGM/FRUGIS/WASULA
SHORT TERM...WASULA
LONG TERM...IAA
AVIATION...FRUGIS
FIRE WEATHER...WASULA
HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
128 PM EDT SUN JUN 23 2013
.SYNOPSIS...
A WARM AND HUMID AIR MASS WILL CONTINUE THIS AFTERNOON THROUGH
THE MIDDLE OF NEXT WEEK. ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS WILL BE POSSIBLE IN THE AFTERNOON AND EARLY EVENING
THE NEXT FEW DAYS. SOME LOCALLY HEAVY RAINFALL WILL BE
POSSIBLE...AND PATCHY FOG WILL BE COMMON WITH MUGGY CONDITIONS
EACH NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1026 AM EDT...A DIFFUSE FRONTAL BOUNDARY CONTINUES TO BE
NORTH OF THE FORECAST AREA THIS MORNING. SOME SHOWERS AND
THUNDERSTORMS MOVED ACROSS THE SOUTHERN ADIRONDACKS EARLY THIS
MORNING...LEAVING UP TO AN INCH OF RAINFALL /ACCORDING TO RADAR
ESTIMATES/ IN SPOTS NEAR INDIAN LAKE.
THE FRONTAL BOUNDARY WILL CONTINUE TO LIFT NORTHWARD DURING THE
DAY...AS A SUBTROPICAL HIGH OFF THE MID ATLANTIC COAST AT THE
SFC...AND ALOFT CONTINUES TO FUNNEL HUMID AIR NORTHWARD. SFC
DEWPTS TODAY WILL RISE INTO THE MID AND U60S IN SOME LOCATIONS
WITH SOUTH TO SOUTHWEST SFC LAYER WINDS. H850 TEMPS INCREASE TO
+16 TO +17C WITH PARTLY TO MOSTLY SUNNY CONDITIONS. MAX TEMPS IN
THE M80S TO NEAR 90F WILL BE LIKELY IN THE VALLEYS WITH U70S TO
L80S OVER THE MTNS.
WEAK MID LEVEL VORTICES MOVING ALONG THE RIM OF THE UPPER LEVEL
RIDGE MAY TRIGGER SOME ISOLD-SCT THUNDERSTORMS TODAY. THE BEST 0-6
KM BULK SHEAR IS ACTUALLY JUST NORTH OF THE FCST AREA ACROSS NRN
NY AND NRN NEW ENGLAND WITH 20-30 KTS. MOST OF THE ALY FCST AREA
WILL BE IN A WEAK SHEAR ENVIRONMENT OF 10-20 KTS FOR PULSE OR VERY
LOOSELY ORGANIZED THUNDERSTORMS. FREEZING LEVELS WILL BE HIGH IN
THE 12-14 KFT AGL RANGE WITH WBZ HEIGHTS AROUND 11 KFT AGL.
SBCAPES WILL BE IN THE 500-1500 J/KG RANGE ACCORDING TO THE GFS.
NOT BUYING INTO THE NAM/S FAIRLY WIDESPREAD LOWER 70S DEWPT AIR OVER
THE REGION WITH SBCAPES OF 2000-3000 J/KG.
THE NEW 12Z NAM...AS WELL AS THE 12Z 3KM HRRR AND THE 12Z LOCAL
HIRES WRF SHOW CELLULAR CONVECTION POPPING UP ACROSS THE
ADIRONDACKS BY THE EARLY TO MID AFTN...AND MORE ACTIVITY
DEVELOPING AND MOVING ACROSS THE MOHAWK VALLEY...CAPITAL REGION
AND SRN VT...BY THE MID/LATE AFTN AND INTO THE EVENING HOURS. EACH
MODEL HAS THE PLACEMENT/TIMING SLIGHTLY DIFFERENT...BUT THE
CONVECTIVE MODE /CELLULAR PULSE TYPE STORMS/ SEEMS TO BE SIMILAR
IN EACH MODEL.
THIS MORNING/S 12Z KALY SOUNDING SHOWED A PWAT OF 1.62. AS A
RESULT...A MENTION OF HVY RAIN HAS BEEN INCLUDED WITH ISOLD-SCT
THUNDERSTORMS TODAY IN THE GRIDDED...TEXT FORECASTS...AND HWO
STATEMENT. AN ISOLD SEVERE MAY BE POSSIBLE TOO...ESPECIALLY IN
THE NRN ZONES...BUT THE FORECASTED WEAK MID LEVEL LAPSE RATES OF
LESS THAN 6 C/KM AND LIMITED AMOUNTS OF SHEAR IN THE 0-6 KM LAYER
SHOULD PROHIBIT WIDESPREAD STRONG CELLS. SPC MAINTAINS A /SEE
TEXT/ AREA ACROSS THE CENTRAL/NORTHERN PART OF THE CWA AND WE WILL
CONTINUE TO MONITOR MESOSCALE TRENDS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
TONIGHT...THE ISOLD TO SCT CONVECTION SHOULD SHRIVEL UP QUICKLY
BEFORE MIDNIGHT WITH THE LOSS OF THE DAYTIME HEATING. A PARTIAL
CLEARING WILL ALLOW PATCHY FOG JUST ABOUT ANYWHERE IN THE FCST
AREA WITH THE MOIST LOW LEVELS. IT HAS BEEN ADDED TO THE FORECAST
GRIDS. STICKY CONDITIONS WILL PREVAIL WITH LOWS IN THE MID AND
U60S IN THE VALLEYS...AND LOWER TO M60S OVER THE HILLS AND MTNS.
MONDAY...THE SULTRY CONDITIONS IN PLACE WILL PROMOTE INCREASED
CHANCES OF MORE PULSE THUNDERSTORMS WITH DEEP SHEAR VALUES LESS
THAN 15 KTS. SBCAPES WILL SOLIDLY BE IN THE 1000-2000 J/KG RANGE.
SOME THUNDERSTORMS MAY BE SLOW MOVERS OR LATCH TO THE TERRAIN FOR
A QUICK INCH OR TWO OF RAINFALL IN THE ANOMALOUSLY HIGH PWAT AIR
MASS. THE NAM SHOWS HINTS OF A SHORT-WAVE TROUGH IN THE W/SW ALOFT
MOVING THROUGH DURING THE AFTERNOON. THE ECMWF/GFS ALSO SHOW A
SUBTLE SHORT-WAVE TROUGH IN THE FLOW ALOFT. THE MID LEVEL LAPSE
RATES STEEPEN TO AROUND 6.5C/KM ON THE GFS. 850HPA THETA-E VALUES
INCREASE TO CLOSE TO 340K ACROSS PORTIONS CNTRL-ERN NY. THE
THETA-E RIDGE WEAKENS SLIGHTLY TOWARDS NIGHT FALL WITH THE PASSAGE
OF THIS TROUGH. HVY RAIN HAS BEEN INCLUDED WITH THE THUNDERSTORMS
AGAIN IN THE GRIDS/TEXT PRODUCTS. H850 TEMPS INCREASE CLOSE TO +17
TO +18C WITH THE GFSMOS TEMPS MUCH WARMER THAN THE METMOS TEMPS. A
BLEND WAS USED WITH A SHADING A LITTLE CLOSER TO THE GFSMOS VALUES
WITH SOUTHWEST TO WEST WINDS IN THE SFC TO BOUNDARY LAYER...TEMPS
MAY SPIKE UP A LITTLE BIT IN THE VALLEYS DUE TO DOWNSLOPING WITH
HIGHS IN THE U80S TO L90S WITH U70S TO M80S OVER THE HILLS AND
MTNS. APPARENT TEMPS COULD GET INTO M90S OR EVEN A FEW U90S IN THE
MID HUDSON VALLEY.
MONDAY NIGHT...SOME SUBSIDENCE OR DRYING ALOFT IN THE WAKE OF THE
TROUGH WILL ALLOW THE SKIES TO GO AT LEAST PARTLY
CLOUDY...ESPECIALLY THE NRN ZONES. PATCHY FOG WILL BE POSSIBLE
AGAIN WITH LOWS IN THE 60S.
TUE-TUE NIGHT...THE BROKEN RECORD FCST CONTINUES WITH DIURNAL
DRIVEN ISOLD-SCT SHOWERS AND THUNDERSTORMS AGAIN. INITIAL
CONVECTION WILL LIKELY BE FROM DIFFERENTIAL HEATING BTWN THE MTNS
AND VALLEYS...BUT POTENTIAL LAKE BREEZES OR WEAK SFC TROUGHS
UPSTREAM WILL HAVE TO BE MONITORED FOR MORE ORGANIZED CONVECTION.
STILL FAVORING THE GFS IN TERMS OF SHEAR AND INSTABILITY. SBCAPES
WILL LIKELY BE IN THE 1000-1500 J/KG RANGE WITH WEAKER MID LEVEL
LAPSE RATES COMPARED TO MONDAY. HIGHS WILL BE SIMILAR TO MON WITH
SOME L90S IN THE HUDSON RIVER VALLEY...AND WIDESPREAD 80S OVER THE
FCST AREA. MUGGY CONDITIONS WILL CONTINUE OVERNIGHT WITH MID AND
U60S IN THE VALLEYS...AND L60S OVER THE HIGH PEAKS.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
THE MODEL GUIDANCE AND ENSEMBLES ARE IN GOOD AGREEMENT WITH THE
LONGWAVE PATTERN AND CONTINUE TO INDICATE THE SUBTROPICAL RIDGE
SETTLES IN OVER THE SOUTHWESTERN UNITED STATES AND AMPLIFIES WITH
TROUGHING OVER THE GREAT LAKES REGION AND NORTHEAST INCREASING.
OVERALL THIS WILL RESULT IN THE WEATHER BECOMING MORE UNSETTLED
OVER THE NORTHEAST AS PIECES OF SHORT WAVE ENERGY MOVE THROUGH THE
TROUGH DEEPENING IT.
THE DIFFERENCES IN THE GUIDANCE LIES WITH THE TIMING OF INDIVIDUAL
SHORT WAVES AND THE MOVEMENT AND PLACEMENT OF BOUNDARIES. A WEAK
BACKDOOR FRONT IS EXPECTED TO MOVE SOUTHWARD INTO THE REGION MID
WEEK THEN RETURN BACK NORTHWARD AS A WARM FRONT LATE IN THE WEEK AS
THE TROUGH DEEPENS OVER THE REGION AND A LOW PRESSURE SYSTEM
APPROACHES. THE REGION IS EXPECTED TO BE IN THE WARM SECTOR OF THE
SYSTEM INTO THE WEEKEND WITH THE SYSTEM`S COLD FRONT EVENTUALLY
CROSSING THE REGION SATURDAY NIGHT/SUNDAY.
TEMPERATURES ARE EXPECTED TO RETURN TO MORE SEASONABLE LEVELS.
HOWEVER DEWPOINTS WILL REMAIN HIGH...IN THE 60S...MAKING FOR HUMID
CONDITIONS.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
WITH A VERY WARM AND MUGGY AIR MASS IN PLACE...SCATTERED SHOWERS AND
THUNDERSTORMS ARE DEVELOPING ACROSS NORTHERN AND WESTERN PORTIONS OF
THE REGION. THERE IS THE POTENTIAL FOR THESE TSRA TO AFFECT
KGFL/KALB/KPOU BY THE LATE AFTN OR EVENING HOURS...SO HAVE INCLUDED
A TEMPO FOR THOSE SITES. KPOU SHOULD REMAIN FAR ENOUGH TO THE SOUTH
AND CAPPED TO AVOID ANY TSTM ACTIVITY. WITHIN ANY TSTM...THERE IS
THE POSSIBILITY OF A QUICK BURST OF HVY RAINFALL AND A STRONG WIND
GUST AS WELL.
ANY TSTM ACTIVITY SHOULD DIMINISH AFTER EVENING WITH THE LOSS OF
HEATING. WITH THE HIGH DEWPOINTS AND LIGHT WINDS IN PLACE...SOME
FOG WILL DEVELOP TONIGHT...ESP IF ANY TERMINALS RECEIVE ANY
RAINFALL. THE SITES MOST LIKELY TO SEE IFR FOG WOULD BE
KGFL/KPSF...MAINLY AFTER MIDNIGHT.
ANY FOG WILL DISSIPATE SHORTLY AFTER SUNRISE ON MONDAY...ALLOWING
FOR VFR CONDITIONS TO RETURN TO ALL SITES FOR MONDAY MORNING.
OUTLOOK...
MON PM-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...MAINLY VFR. CHC -TSRA/-SHRA.
&&
.FIRE WEATHER...
A WARM AND HUMID AIR MASS WILL CONTINUE TODAY THROUGH
THE MIDDLE OF NEXT WEEK. ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS WILL BE POSSIBLE IN THE AFTERNOON AND EARLY EVENING
THE NEXT FEW DAYS.
RH LEVELS WILL REMAIN HIGH EACH NIGHT INTO THE MIDDLE OF NEXT WEEK
FOR THE FORMATION OF DEW ACROSS EASTERN NEW YORK AND WESTERN NEW
ENGLAND. NO FIRE WEATHER CONCERNS ARE EXPECTED AT THIS TIME.
&&
.HYDROLOGY...
FLOWS CONTINUE TO RECEDE TO LATE JUNE SEASONAL LEVELS. THE NEXT 5
DAYS WILL FEATURE ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS
WHICH WILL LIKELY NOT HAVE A SIGNIFICANT IMPACT ON THE MAIN STEM
RIVERS.
SLOW MOVING THUNDERSTORMS COULD PRODUCE A QUICK INCH OR TWO OF
RAINFALL WITH HIGHER THAN NORMAL PRECIPITABLE WATER VALUES OVER
THE HYDRO SERVICE AREA. SOME POOR DRAINAGE FLOODING OF LOW LYING
AREAS...AND PONDING OF WATER ON ROADWAYS WILL BE POSSIBLE ANY DAY
INTO THURSDAY. SOME SMALL STREAMS...CREEKS...AND BROOKS MAY REACH
BANKFULL QUICKLY IN THE HEAVY RAINFALL ASSOCIATED WITH THE
THUNDERSTORMS.
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...FRUGIS/WASULA
NEAR TERM...FRUGIS/WASULA
SHORT TERM...WASULA
LONG TERM...IAA
AVIATION...FRUGIS
FIRE WEATHER...WASULA
HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
421 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 18Z...
* SOUTH/SOUTHWEST WINDS EXPECTING THROUGH THIS
AFTERNOON...POSSIBLY BECOMING MORE SOUTHWEST AS OUTFLOW BOUNDARY
APPROACHES FROM THE WEST.
* SLIGHT POSSIBILITY FOR AN ISOLATED SHOWER LATE THIS AFTERNOON.
* POSSIBILITY FOR A CONTINUED ACTIVE PERIOD WITH SEVERAL CHANCES
FOR SHOWERS/THUNDERSTORMS TO MOVE ACROSS THE TERMINALS TONIGHT
THROUGH MONDAY AFTERNOON.
RODRIGUEZ
//DISCUSSION...UPDATED 18Z...
VERY COMPLEX FORECAST PERIOD AS THE POTENTIAL FOR AN ACTIVE
WEATHER PATTERN OVER THE TERMINALS REMAINS. DESPITE AN ABUNDANCE
OF MOISTURE AND INSTABILITY ACROSS THE AREA...THERE IS A LACK OF
ANY CLEAR GOOD FORCING MECHANISMS WITH PRECIP TRENDS LOW AT THIS
TIME WITH MODEL GUIDANCE NOT TOO MUCH OF ANY HELP. ALTHOUGH IN THE
NEAR TERM...CONTINUE TO MONITOR SOME FAIRLY WEAK MID LEVEL
FEATURES AS WELL AS SEVERAL OUTFLOW BOUNDARIES PROPAGATING ACROSS
THE REGION. WITH THESE FEATURES IN PLACE...THERE IS THE
POSSIBILITY FOR SHOWERS OR EVEN AN ISOLATED THUNDERSTORM. ALTHOUGH
DESPITE THE BOUNDARIES/MID LEVEL FEATURES...THE ORIENTATION AND
WEAKNESS OF THEM SHOULD ONLY PROVIDE ISOLATED TO AT BEST WIDELY
SCATTERED DEVELOPMENT THIS AFTERNOON WITH ANYTHING THAT DOES
DEVELOP TO BE ON THE BRIEF SIDE. SO WITH THIS LOW COVERAGE/LOW
CONFIDENCE OF THIS AT THIS TIME...HAVE OPTED TO LEAVE OUT ANY
MENTION OF PRECIP AT THIS TIME. WILL ALSO NEED TO CONTINUE TO
MONITOR THE POTENTIAL FOR UPSTREAM DEVELOPMENT LATER THIS EVENING
TO POSSIBLY SHIFT EAST ACROSS THE TERMINALS LATER TONIGHT...AS
ONCE AGAIN CONFIDENCE REMAINS LOW AT THIS POSSIBILITY. AS WAS
MENTIONED ABOVE...SEVERAL FEATURES COULD MOVE ACROSS THE REGION
ONCE AGAIN ON MONDAY WITH SHOWERS/THUNDERSTORMS ONCE AGAIN
POSSIBLE. WITH CONTINUED LOW CONFIDENCE AT THIS TIME...HAVE ONCE
AGAIN LEFT OUT ANY MENTION OF PRECIP.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE WITH WIND SPEED AND DIRECTION THROUGH THIS
AFTERNOON...WITH LOW MEDIUM CONFIDENCE OF THE MORE SOUTHWEST
DIRECTION WITH THE PASSAGE OF THE BOUNDARY.
* LOW CONFIDENCE OF SHOWERS THIS AFTERNOON.
* LOW CONFIDENCE WITH PRECIP/CONVECTIVE TRENDS THIS PERIOD.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT THROUGH FRIDAY...PERIODIC CHANCES OF TSRA.
SATURDAY...MAINLY VFR. CHC OF SHOWERS.
BEACHLER
&&
.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 CHICAGO/ROMEOVILLE IL
306 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 18Z...
* SOUTH/SOUTHWEST WINDS EXPECTING THROUGH THIS
AFTERNOON...POSSIBLY BECOMING MORE SOUTHWEST AS OUTFLOW BOUNDARY
APPROACHES FROM THE WEST.
* SLIGHT POSSIBILITY FOR AN ISOLATED SHOWER LATE THIS AFTERNOON.
* POSSIBILITY FOR A CONTINUED ACTIVE PERIOD WITH SEVERAL CHANCES
FOR SHOWERS/THUNDERSTORMS TO MOVE ACROSS THE TERMINALS TONIGHT
THROUGH MONDAY AFTERNOON.
RODRIGUEZ
//DISCUSSION...UPDATED 18Z...
VERY COMPLEX FORECAST PERIOD AS THE POTENTIAL FOR AN ACTIVE
WEATHER PATTERN OVER THE TERMINALS REMAINS. DESPITE AN ABUNDANCE
OF MOISTURE AND INSTABILITY ACROSS THE AREA...THERE IS A LACK OF
ANY CLEAR GOOD FORCING MECHANISMS WITH PRECIP TRENDS LOW AT THIS
TIME WITH MODEL GUIDANCE NOT TOO MUCH OF ANY HELP. ALTHOUGH IN THE
NEAR TERM...CONTINUE TO MONITOR SOME FAIRLY WEAK MID LEVEL
FEATURES AS WELL AS SEVERAL OUTFLOW BOUNDARIES PROPAGATING ACROSS
THE REGION. WITH THESE FEATURES IN PLACE...THERE IS THE
POSSIBILITY FOR SHOWERS OR EVEN AN ISOLATED THUNDERSTORM. ALTHOUGH
DESPITE THE BOUNDARIES/MID LEVEL FEATURES...THE ORIENTATION AND
WEAKNESS OF THEM SHOULD ONLY PROVIDE ISOLATED TO AT BEST WIDELY
SCATTERED DEVELOPMENT THIS AFTERNOON WITH ANYTHING THAT DOES
DEVELOP TO BE ON THE BRIEF SIDE. SO WITH THIS LOW COVERAGE/LOW
CONFIDENCE OF THIS AT THIS TIME...HAVE OPTED TO LEAVE OUT ANY
MENTION OF PRECIP AT THIS TIME. WILL ALSO NEED TO CONTINUE TO
MONITOR THE POTENTIAL FOR UPSTREAM DEVELOPMENT LATER THIS EVENING
TO POSSIBLY SHIFT EAST ACROSS THE TERMINALS LATER TONIGHT...AS
ONCE AGAIN CONFIDENCE REMAINS LOW AT THIS POSSIBILITY. AS WAS
MENTIONED ABOVE...SEVERAL FEATURES COULD MOVE ACROSS THE REGION
ONCE AGAIN ON MONDAY WITH SHOWERS/THUNDERSTORMS ONCE AGAIN
POSSIBLE. WITH CONTINUED LOW CONFIDENCE AT THIS TIME...HAVE ONCE
AGAIN LEFT OUT ANY MENTION OF PRECIP.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE WITH WIND SPEED AND DIRECTION THROUGH THIS
AFTERNOON...WITH LOW MEDIUM CONFIDENCE OF THE MORE SOUTHWEST
DIRECTION WITH THE PASSAGE OF THE BOUNDARY.
* LOW CONFIDENCE OF SHOWERS THIS AFTERNOON.
* LOW CONFIDENCE WITH PRECIP/CONVECTIVE TRENDS THIS PERIOD.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT THROUGH FRIDAY...PERIODIC CHANCES OF TSRA.
SATURDAY...MAINLY VFR. CHC OF SHOWERS.
BEACHLER
&&
.MARINE...
326 AM CDT
BROAD RIDGE OF HIGH PRESSURE REMAINS ANCHORED ACROSS THE WESTERN
ATLANTIC OCEAN STRETCHING NORTH THROUGH QUEBEC. A TROUGH OF LOW
PRESSURE OVER THE CENTRAL PLAINS WILL LIFT NORTH INTO
ALBERTA...THEN SLOWLY SLIDE EAST ACROSS CENTRAL ONTARIO MONDAY
WITH A TRAILING FRONTAL BOUNDARY SAGGING SOUTH ACROSS MID LAKE
MONDAY. THIS FRONTAL BOUNDARY WILL THEN STRETCH WEST THROUGH
CENTRAL IOWA...AS ANOTHER AREA OF LOW PRESSURE WILL DEVELOP
ACROSS THE CENTRAL PLAINS AND SLOWLY SLIDE NORTHEAST TOWARDS THE
UPPER MIDWEST WEDNESDAY NIGHT INTO THURSDAY. AT TIMES WINDS WILL
BECOME GUSTY THIS AFTERNOON TO 20-25KT...HOWEVER WITH THE VERY
WARM/MOIST AIR FLOWING OVER THE COOLER LAKE THIS MAY HOLD GUSTS
DOWN ARND 20KT.
THE OTHER CONCERN FOR TODAY/TONIGHT AND THROUGH MONDAY WILL BE ON
FOG. IT DOES APPEAR THAT PATCHY DENSE FOG WILL HOVER OVER THE
LAKE...MAINLY THE NORTHERN HALF AGAIN TODAY THROUGH TONIGHT.
HOWEVER WITH A CONTINUED FEED OF WIND...IT DOES NOT APPEAR
FAVORABLE FOR WIDESPREAD DENSE FOG AT THIS TIME. SO HAVE OPTED TO
KEEP MENTION AS PATCHY DENSE FOG.
WINDS WILL REMAIN SOUTHERLY THROUGH THE NEXT SEVERAL DAYS...UNTIL
A PATTERN CHANGE DEVELOPS LATE IN THE UPCOMING WEEK. THEN WINDS
WILL BEGIN TO SHIFT WEST/NORTHWEST TOWARDS FRIDAY/SATURDAY.
BEACHLER
&&
.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
103 PM CDT SUN JUN 23 2013
.DISCUSSION...
ISSUED 1027 AM CDT SUN JUN 23 2013
CURRENT CONVECTION OVER SOUTHEAST CWA FIRING OFF LEFTOVER
BOUNDARIES FROM YESTERDAYS STORMS AND LIFT OFF WESTERN FRINGE OF
CLOSED MID LEVEL LOW CENTERED OVER KY. THIS OCCURRING IN A VERY
HIGH 1.8 P/W AIRMASS AND WEAK WINDS ALOFT SO STORMS ARE SLOW
MOVERS AND POSE A HEAVY RAIN THREAT. HI-RES MODELS GRADUALLY PUSH
THIS AREA EAST AFFECTING MUCH OF SE IL THROUGH MID AFTERNOON.
OTHER AREA OF CONCERN IS LINE OF STORMS SHIFTING THROUGH CENTRAL
IA WHICH HAS SHOWN RECENT CLOUD TOP COOLING ON IR SAT IMAGERY. IF
THIS HOLDS TOGETHER LIKELY WOULDNT REACH WESTERN CWA UNTIL
EVENING. HOWEVER OUTFLOW PUSHING AHEAD OF THIS ALREADY INTO
EASTERN IA EVIDENT ON KDVN REFLECTIVITY IMAGERY. AWIPS DISTANCE
SPEED TOOL BRINGS THIS INTO KNOX CO NEAR NOON AND WILL NEED TO
MONITOR NEW CONVECTION POSSIBLY FIRING ALONG/BEHIND THIS AS HAS
OCCURRED IN CWA PAST TWO DAYS. AIRMASS SHOWS LITTLE CHANGE FROM
YESTERDAY WITH HIGH P/W WEAK WINDS ALOFT AND MODERATE INSTABILITY.
THEREFORE HEAVY RAIN REMAINS PRIMARY THREAT THROUGH BULK SHEAR
INCREASES TO 30 KTS THIS AFTERNOON ACROSS THE WESTERN HALF AND
WOULD GIVE SOME ORGANIZATION FOR A LOW END SVR WIND AND HAIL
THREAT. HAVE INCREASED POPS TO LIKELY OVER THE SOUTHEAST INTO
EARLY AFTERNOON...THEN HAVE CHANCE POPS OVER REMAINDER OF CWA WITH
HIGHEST CHANCES OVER THE WEST. HIGHS WILL AGAIN REACH THE LOWER
90S IN AREAS THAT SEE MORE SUN AND WITH DEWPOINTS AROUND 70 PEAK
HEAT INDICES WILL BE IN THE UPPER 90S.
&&
.AVIATION...
ISSUED 102 PM CDT SUN JUN 23 2013
ISOLATED THUNDERSTORMS BEGINNING TO DEVELOP AS CONVECTIVE TEMPS
ARE REACHED THIS AFTERNOON AND HAVE VCTS UNTIL 02Z. A BETTER
CHANCE FOR STORMS MID AFTERNOON INTO EARLY EVENING AS COMPLEX
CURRENTLY PUSHING INTO EASTERN IA MOVES ACROSS CENTRAL IL. LATEST
RUN OF HI-RES MODELS INDICATES THIS AFFECTING CENTRAL IL TERMINALS
BEGINNING AT 20Z AT KPIA AND EXITING KCMI AROUND 02Z. TEMPO VSBY
REDUCTIONS AND MVFR CEILINGS DURING THIS TIMEFRAME. ISOLATED
HEAVIER CELLS COULD BRING IFR CEILINGS/VSBYS AND GUSTY VARIABLE
WINDS FOR A BRIEF TIME. AFTER THIS ACTIVITY SHIFTS EAST THIS
EVENING...LOW CONFIDENCE IN REDEVELOPMENT OVERNIGHT WITH HIGHER
CHANCES TO OUR WEST. SOUTHWEST WINDS GUSTING AROUND 20 KTS THIS
AFTERNOON WILL SUBSIDE TO UNDER 10 KTS AFTER O2Z...THEN PICK UP TO
10-15 KTS AFTER 14Z/MON.
25
&&
.PREV DISCUSSION...
ISSUED 230 AM CDT SUN JUN 23 2013
SHORT TERM...TODAY THROUGH TUESDAY...
PROBLEMATIC FORECAST CONTINUES FOR THE NEXT FEW DAYS IN REGARDS TO
CONVECTIVE DEVELOPMENT. EVENTS OF THE LAST COUPLE DAYS HAVE SHOWN
HOW LEFTOVER BOUNDARIES LEAD TO REDEVELOPMENT IN THE HEAT OF THE
DAY...AND ANOTHER SUCH BOUNDARY IS DROPPING SOUTHWARD THROUGH
FAR NORTHERN ILLINOIS...FORMED BY A DECAYING MCS OVER WISCONSIN
AND SOUTHEAST MINNESOTA. SOME WEAK BOUNDARIES ALSO DETECTED OVER
SOUTHEAST ILLINOIS LOOPING WESTWARD INTO AREAS SOUTHWEST OF SAINT
LOUIS. STORMS THAT FORM TODAY SHOULD BE VERY EFFICIENT RAIN MAKERS
AGAIN...AS PRECIPITABLE WATER VALUES WILL BE AROUND 1.7 INCHES AND
700 MB WINDS OF LESS THAN 10 KNOTS INDICATE THE STORMS WILL BE IN
NO HURRY TO MOVE ONCE THEY FORM. LATEST RAP AND HRRR MODELS SHOW
SOME DEVELOPMENT TAKING PLACE AS EARLY AS SUNRISE NEAR THE
SOUTHERN OUTFLOW...AND AFTERNOON DEVELOPMENT SHOULD ACCOMPANY THE
NORTHERN BOUNDARY. HAVE GONE A LITTLE MORE AGGRESSIVE WITH THE
POPS AS A RESULT WITH 30-40 PERCENT MOST AREAS TODAY.
OVERNIGHT PROBLEM THEN SHIFTS TO TRACK OF THE NEXT MCS WHICH
SHOULD FORM OVER IOWA THIS EVENING. NAM AND GFS ARE MORE
PROGRESSIVE WITH SPREADING IT OVER MUCH OF ILLINOIS BY EARLY
MONDAY MORNING...WHILE THE LATEST ECMWF IS SLOWER AND SHUNTS MOST
OF IT OFF TO OUR NORTH. LEANING TOWARD A MORE SOUTHERN SOLUTION AT
THE MOMENT WITH 40-50 PERCENT POPS FROM ABOUT I-55 NORTHWEST...
WITH MAINLY SLIGHT CHANCES ACROSS THE SOUTHEAST. ONCE THIS
PARTICULAR MCS EXITS ON MONDAY...THE STORM TRACK FOR THE NEXT
ROUND SHIFTS A BIT FURTHER NORTH AS SOME UPPER RIDGING BUILDS INTO
THE MID-MISSISSIPPI VALLEY.
TEMPERATURE-WISE...STILL LOOKING LIKE 90 DEGREES OR A BIT HIGHER
IS LIKELY THE NEXT FEW DAYS...PROVIDED THE STORMS DO NOT GET OUT
OF CONTROL. SLOW BUILD OF THE DEW POINTS TOWARD THE MID 70S WILL
RESULT IN HEAT INDEX VALUES A FEW DEGREES HIGHER EACH DAY...WITH
MOST AREAS JUST ABOVE 100 FOR HEAT INDEX BY TUESDAY AFTERNOON.
LONG TERM...WEDNESDAY THROUGH SATURDAY...
SUMMER-TIME PATTERN TO CONTINUE THROUGH MID WEEK. MAIN STORM TRACK
WILL BE ACROSS THE NORTH CENTRAL STATES...WITH SOME POTENTIAL FOR
SHOWERS/STORMS FURTHER SOUTH AS THE OUTFLOWS FROM THE NIGHTLY MCS
SYSTEMS DROP INTO OUR AREA. BEST CHANCE OF RAIN WILL PROBABLY BE
WEDNESDAY NIGHT...AS A SHORTWAVE DROPS INTO THE MIDWEST ALONG WITH
AN ASSOCIATED SURFACE BOUNDARY.
AS THE END OF THE WEEK PROGRESSES...UPPER LEVEL RIDGING WILL BUILD
ACROSS THE ROCKIES...WITH A NORTHWEST FLOW BRINGING COOLER
CONDITIONS TO THE MIDWEST FOR FRIDAY AND ESPECIALLY THE WEEKEND.
THINK MOST OF THE RAIN THREAT WILL BE OUT OF THE AREA BY THURSDAY
EVENING...BUT WEAK TROUGHS ROTATING THROUGH THE MIDWEST MAY
COMPLICATE THIS THINKING.
GEELHART
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WICHITA KS
109 PM CDT SUN JUN 23 2013
.UPDATE...
ISSUED AT 109 PM CDT SUN JUN 23 2013
ELEVATED SHOWER/THUNDERSTORM ACTIVITY CONTINUES TO WANE AS
EXPECTED ALONG THE TURNPIKE CORRIDOR. OTHERWISE...ADDITIONAL
SCATTERED THUNDERSTORMS ARE EXPECTED TO FORM LATE THIS
AFTERNOON/EARLY EVENING ALONG A FRONT/OLD CONVECTIVE OUTFLOW
DRAPED ACROSS CENTRAL/NORTHERN KS. DESPITE THE LAST SEVERAL RUNS
OF THE HRRR...THERE REMAINS QUESTIONS REGARDING CONVECTIVE
COVERAGE EARLY ON GIVEN CAP STRENGTH...ALTHOUGH PROBABILITIES
SHOULD INCREASE BY MID-EVENING AS LOW-LEVEL JET INTENSIFIES.
ML INSTABILITY UPWARDS OF 2500-3000 J/KG IN CONCERT WITH 25-40 KTS
OF MID-LEVEL FLOW WILL LIKELY BE ENOUGH TO PRODUCE STRONG/SEVERE
STORMS CAPABLE OF GOLFBALL SIZE HAIL AND DAMAGING DOWNBURST
WINDS...WITH ACTIVITY POSSIBLY EVENTUALLY EVOLVING INTO A SEVERE
MCS AS THE EVENING/OVERNIGHT PROGRESSES.
ADK
&&
UPDATE ISSUED AT 902 AM CDT SUN JUN 23 2013
PERSISTENT 315-320K ISENTROPIC ASCENT AMIDST A MOIST/UNSTABLE
AIRMASS AS DEPICTED BY RUC SHOULD ALLOW ISOLATED TO WIDELY
SCATTERED SHOWERS/THUNDERSTORMS TO LINGER THROUGH A GOOD PORTION
OF THE MORNING OVER PORTIONS OF EAST-CENTRAL AND SOUTH-CENTRAL KS.
ACTIVITY IS LIKELY ROOTED AT AND ABOVE 700MB...SO AVAILABLE
INSTABILITY TO WORK WITH ISN`T FANTASTIC FOR HAIL PRODUCTION...BUT
PROBABLY ENOUGH FOR SMALL HAIL IN THE STRONGEST CORES. AS
ATMOSPHERE BECOMES BETTER MIXED WITH DAYTIME HEATING AND 800-600MB
FLOW BACKS...ANTICIPATE THIS ACTIVITY TO GRADUALLY DISSIPATE BY
AROUND LUNCHTIME.
ADK
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 236 AM CDT SUN JUN 23 2013
LEE LOW WILL PERSIST NEAR THE CO/KS BORDER DURING THE PERIOD BENEATH
SOUTHWESTERLY MID-LEVEL FLOW PATTERN. THIS WILL MAINTAIN STRONG A
THERMAL RIDGE AND VERY WARM TEMPERATURES IN OUR AREA ALONG WITH
GUSTY SOUTHERLY WINDS. A WEAK COLD FRONT POSSIBLY AIDED BY
CONVECTIVE OUTFLOW FROM MCS IN NEBRASKA...WILL SINK INTO
NORTHWESTERN KS THIS MORNING BEFORE STALLING. VERY STRONG
INSTABILITY WILL DEVELOP THIS AFTERNOON IN OUR AREA AND NORTH OF THE
FRONT WHERE LOW-LEVEL MOISTURE WILL BE POOLING. A FEW STORMS MAY
TRY TO GET GOING IN THE WEAK FRONTAL CONVERGENCE ZONE LATE THIS PM
ALTHOUGH CONVECTIVE INHIBITION MAY BE TOO STRONG TO OVERCOME. THE
MORE PROBABLE SCENARIO IS THAT STORMS WILL FORM OVER THE HIGHER
TERRAIN TO OUR WEST/NORTHWEST IN UPSLOPE FLOW IN THE PM/EVE...AND MOVE
EASTWARD VIA CORFIDI PROPAGATION VECTORS SUNDAY NIGHT ACROSS
NORTHERN KS/SOUTHERN NEB AS AN MCS CLUSTER OR TWO. THIS ACTIVITY
WILL BE AIDED BY A WEAK SHORTWAVE OVER SOUTHERN CA EARLY THIS AM.
THIS COULD AFFECT OUR CENTRAL KS COUNTIES ESP NEAR/NORTH OF I-70.
STRONG-SEVERE WIND GUSTS COULD ACCOMPANY ANY STORMS THIS PM AND
TONIGHT WITH DCAPES OF 1500-2000 J/KG. THE PROGGED FRONTAL
SURFACE/OUTFLOW BOUNDARY SHOULD LIFT NORTH OF OUR AREA MONDAY WITH
STRONG SOUTHERLY WINDS DEVELOPING IN CENTRAL/SOUTH CENTRAL KS. A
WIND ADVISORY MAY BE REQUIRED.
JMC
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 236 AM CDT SUN JUN 23 2013
THE MEDIUM RANGE MODELS REMAIN CONSISTENT IN DEPICTING AN AMPLIFYING
UPPER PATTERN ACROSS THE CONUS...FEATURING A STRONG UPPER LEVEL HIGH
DEVELOPING OVER THE SOUTHERN ROCKIES WITH UPPER TROUGHING DEEPENING
OVER THE NORTHEAST. WEDNESDAY INTO THURSDAY WILL REMAIN HOT WITH
HIGHS 100-103 IN CENTRAL/SOUTH CENTRAL KS...AND UPPER 90S SOUTHEAST.
THE UPPER FLOW PATTERN WILL ALLOW A WEAK COLD FRONT TO PUSH SLOWLY
SOUTHWARD THROUGH OUR AREA WITH SLIGHTLY COOLER/LESS HOT WEATHER BY
FRIDAY/SATURDAY. VERY SLIGHT CHANCE OF THUNDERSTORMS AS THE FRONT
MOVES THROUGH...TIED MAINLY TO WEAK FRONTAL CONVERGENCE AND STRONG
DIURNAL HEATING. NOT OPTIMISTIC THAT MANY PLACES WILL GET RAIN HOWEVER.
JMC
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 109 PM CDT SUN JUN 23 2013
STRONG/GUSTY SOUTHERLY WINDS WILL CONTINUE TO AFFECT THE REGION
THROUGH THE NEXT 24 HOURS. OUTFLOW BOUNDARY/FRONT WILL BE FOCUS
FOR SCATTERED THUNDERSTORM DEVELOPMENT LATE THIS AFTERNOON/EVENING
FOR KSLN-KRSL...SOME OF WHICH COULD BE STRONG/SEVERE WITH LARGE
HAIL AND DAMAGING WINDS. LATER TONIGHT WHEN ACTIVITY HAS
WEAKENED...CANNOT COMPLETELY RULE OUT A FEW REMNANT
SHOWERS/THUNDERSTORMS GETTING INTO KHUT-KICT.
ADK
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 95 74 95 76 / 20 10 10 0
HUTCHINSON 97 74 97 76 / 10 20 10 10
NEWTON 94 74 95 75 / 20 10 10 0
ELDORADO 92 74 93 75 / 20 10 10 0
WINFIELD-KWLD 94 74 94 76 / 20 10 10 0
RUSSELL 98 70 99 75 / 30 40 10 10
GREAT BEND 98 71 99 75 / 20 30 10 10
SALINA 96 72 97 76 / 30 40 10 10
MCPHERSON 96 74 96 76 / 10 20 10 10
COFFEYVILLE 91 74 92 75 / 10 10 10 0
CHANUTE 91 74 91 75 / 10 10 10 0
IOLA 91 74 91 74 / 10 10 10 0
PARSONS-KPPF 90 74 91 75 / 10 10 10 0
&&
.ICT WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAY ME
342 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 /TONIGHT/...
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 DOWNBURSTS. 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 /MONDAY 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 /18Z 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.
&&
$$
HANES/KIMBLE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
422 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 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 157 PM EDT SUN JUN 23 2013
VFR CONDITIONS ARE EXPECTED THROUGH MOST OF THE AFTERNOON.
HOWEVER...SCT SHRA/TSRA ARE EXPECTED TO DEVELOP AND MOVE THROUGH
CMX/SAW WHICH WOULD BRING A PERIOD OF MVFR CONDITIONS WITH THE
POTENTIAL FOR GUSTY WINDS. HOWEVER...THERE WAS STILL SOME UNCERTAINTY
WITH THE TIMING/COVERAGE OF ANY TSRA. AFTER A TROUGH MOVES THROUGH
THIS EVENING...SLIGHTLY DRIER AIR WILL MOVE IN KEEPING MAINLY VFR
CONDITIONS INTO MONDAY MORNING.
&&
.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...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
325 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 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1246 PM CDT SUN JUN 23 2013
TEMPORARY MVFR CONDITIONS FORECAST THROUGH 19Z...WITH PREVAILING
VFR CONDITIONS OTHERWISE FORECAST THROUGH THE NEXT 24 HOURS.
A PERIODIC CEILING NEAR 2000FT AGL CONTINUES TO APPEAR AT KGRI. AS
DIABATIC HEATING CONTINUES TO INCREASE HOWEVER...ANY LINGERING
STRATUS SHOULD BREAK APART AND INCREASE IN HEIGHT...WITH
PREVAILING VFR CONDITIONS EXPECTED BY 19Z. PASSING CLOUDS...WITH
BASES BETWEEN 3000FT AGL AND 8000FT AGL WILL THEN REMAIN POSSIBLE
THROUGH THE REMAINDER OF THE TAF PERIOD....WITH SCATTERED CLOUDS
CLOSER TO 15000FT AGL ALSO FORECAST. THERE IS A LOW CHANCE FOR
SHOWER AND THUNDERSTORM ACTIVITY AT KGRI THROUGH TONIGHT. THE
PROBABILITY OF SUCH CONDITIONS BEING OBSERVED AT KGRI IS TOO LOW
FOR INSERTION INTO THE TAF AT THIS TIME HOWEVER. THE SURFACE WIND
WILL REMAIN LIGHT AND VARIABLE FOR THE MOST PART THROUGH TONIGHT
BEFORE BECOMING MORE ESTABLISHED FROM THE SOUTHEAST MONDAY
MORNING. THE AXIS OF A LOW LEVEL JET...WITH SUSTAINED WINDS NEAR
45KTS...IS EXPECTED TO DEVELOP OVER PORTIONS OF KANSAS TONIGHT. AT
THIS TIME IT APPEARS THIS LOW LEVEL JET WILL REMAIN FAR ENOUGH
SOUTH THUS PREVENTING THE DEVELOPMENT OF LOW LEVEL WIND SHEAR AT
KGRI. THAT BEING SAID...THE DEVELOPMENT OF THIS LOW LEVEL JET WILL
NEED TO BE MONITORED TO ENSURE IT DOES NOT MOVE FARTHER NORTH THAN
CURRENTLY FORECAST...OTHERWISE LOW LEVEL WIND SHEAR COULD
POTENTIALLY BE OBSERVED AT KGRI OVERNIGHT TONIGHT. VISIBILITY
RESTRICTION IS NOT EXPECTED AT KGRI THROUGH THE NEXT 24 HOURS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...BRYANT
LONG TERM...WESELY
AVIATION...BRYANT
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1132 AM MDT SUN JUN 23 2013
.AVIATION...
18Z TAF CYCLE
VFR CIGS AND VIZ NEXT 24 HOURS. AFTERNOON ISOLD CONVECTION DVLPG
AFTER 20Z OVER EXTREME SOUTHEAST NM NEAR TX BORDER...AND IN
NORTHEAST CORNER OF NM NEAR OK PANHANDLE. TURBULENT SOUTHWEST FLOW
CONTINUING ALOFT AS SURFACE LOW PRESSURE DEEPENS OVER THE OK
PANHANDLE AND EXTENDS TROUGH ACROSS EASTERN NM TO WEST TX BIG BEND
COUNTRY. GUSTY SOUTHWEST WINDS DEVELOPING AFTER 19Z THIS AFTERNOON
WILL BE TYPICALLY G25KTS...WITH G30KTS IN TAF FOR LVS OVER EAST
SLOPES OF THE SANGRE DE CRISTO RANGE AND CENTRAL MT CHAIN. SPEEDS
DECREASING AFTER 03Z SUNSET TONIGHT. SIMILAR WIND REGIME ON TAP
FROM 16Z ONWARD MON MORNING.
SHY
&&
.PREV DISCUSSION...320 AM MDT SUN JUN 23 2013...
.DISCUSSION..
DRY LINE HAS MADE LESS PROGRESS WESTWARD ATTM THAN IN PREVIOUS
NIGHTS...AND AT 3 AM WAS STRETCHED FROM KROW NORTHEAST TO NEAR KCAO.
AT THE SAME TIME...A BOUNDARY FROM APPARENTLY THE CONVECTIVE COMPLEX
OVER WRN NE AND KS...OR AT LEAST AIDED BY IT...HAD SAGGED TO KLHX
AND KLAA. LATEST RUC13 INDICATES THE BOUNDARY COULD REACH KTCC OR
EVEN FARTHER SOUTH BY MID MORNING...AND BY EARLY AFTERNOON IT COULD
BE STRETCHED FROM THE RATON AREA TO KTCC. 06Z NAM MAKES FOR AN
INTERESTING FORECAST WITH THE SURFACE LOW REMAINING CENTERED NEAR
KLVS RATHER THAN LIFTING INTO NE CO LATE THIS AFTERNOON. THIS CHANGE
COULD RESULT IN A LITTLE LESS WIND...AS WELL AS A LITTLE MORE AREAL
COVERAGE OF THE SLIGHT CHANCE POPS WE CURRENTLY HAVE PAINTED IN FAR
NE NM. OTHERWISE...SHOULD BE LESS HIGH CLOUDS AROUND TODAY WITH
LITTLE CHANGE IN HIGH TEMPERATURES FOR MOST LOCALES.
WINDS TO BE A BIT STRONGER MONDAY...SHUNTING ANY MID LEVEL MOISTURE
THAT TRIES TO WORK IT/S WAY NORTHWARD INTO SOUTHERN AND EASTERN
SECTIONS OF THE STATE...ALTHOUGH IT/S NOW FORECAST TO BE SOMEWHAT
LESS THAN PREVIOUS MODEL RUNS SUGGESTED...AND SEEPAGE INTO SOUTHWEST
NM APPEARS LESS LIKELY. STILL THERE IS PLENTY OF MOISTURE JUST SOUTH
OF THE BORDER SO LEFT POPS PRETTY MUCH ALONE. DRY LINE CAN/T SEEM TO
MAKE MUCH PROGRESS WESTWARD FOR THE NEXT FEW DAYS WITH THE LEE
TROUGH STAYING PUT. UPPER HIGH REMAINS PROGGED TO SHIFT NORTHWARD BY
TUESDAY ALLOWING WINDS TO RELAX...HEADING FOR THE FOUR CORNERS
REGION MID TO LATE WEEK. WEDNESDAY INTO THURSDAY COULD BE THE
HOTTEST DAYS OF THE WEEK FOR THE CENTRAL AND WEST. EVIDENCE OF A
FRONT INVADING THE EASTERN PLAINS FRIDAY-ISH COULD SPARK SHOWERS AND
STORMS IN THE NORTH CENTRAL/EAST. BY NEXT WEEKEND...THE HIGH CENTER
STARTS TRIPPING TOWARD SALT LAKE...WITH POTENTIAL FOR CONVECTION TO
DEVELOP OVER THE NRN HIGH TERRAIN AND DRIFT SOUTH TO SOUTHWESTWARD
INTO CENTRAL/WRN VALLEYS.
.FIRE WEATHER...
...CRITICAL FIRE WEATHER CONDITIONS EXPECTED OVER MUCH OF CENTRAL TO
EASTERN NM TODAY WITH MORE WIDESPREAD CONDITIONS ON MONDAY...
TODAY`S FORECAST WILL BE TRICKY...ESPECIALLY WITH REGARDS TO THE
WINDS. THIS WILL HAVE LARGE IMPLICATIONS ON THE DURATION AND SPATIAL
EXTENT OF CRITICAL FIRE WEATHER THIS AFTERNOON. OVERALL...THE MAIN
FEATURES THAT HAVE BEEN DICTATING THE WEATHER PATTERN THE PAST FEW
DAYS ARE STILL AT WORK...WITHOUT ANY BLATANT OR LARGE CHANGES. ANY
DIFFERENCES WILL BE FAIRLY SUBTLE. HOWEVER...MIXING HEIGHTS MAY
EXCEED YESTERDAY`S LEVELS DUE TO LESS HIGH CIRRUS CLOUDS. MODEL
DEPICTION OF MIXING HEIGHTS IS RATHER SPLOTCHY...INDICATIVE THAT IT
IS HAVING DIFFICULTY RESOLVING IT. ALSO...SOUTHWESTERLIES ALOFT
REMAIN RELATIVELY STRONG FOR LATE JUNE...HOSTING SPEEDS OF 15-20 KT
AT H7 AND UP TO 20-25 KT AT H5 WHICH SHOULD BE WITHIN THE MIXED
LAYER OF MOST SITES. THE EASTERN HALF OF THE FORECAST AREA WILL ALSO
HAVE POTENTIAL FOR A BETTER SURFACE PRESSURE GRADIENT...DEPENDING ON
WHERE THE LEE SIDE SURFACE LOW ESTABLISHES ITSELF. A CLUSTER OF
CONVECTION IN THE CENTRAL PLAINS OF THE NATION HAS HELPED USHER A
BOUNDARY SOUTHWARD INTO COLORADO. IF THIS BOUNDARY SPILLS FARTHER
SOUTH INTO NM...BEYOND WHAT MOST MODELS ARE INDICATING...IT COULD
WREAK HAVOC ON WIND FORECAST DUE TO ORIENTATION OF THE SURFACE LOW
AND ASSOCIATED GRADIENT. HUMIDITY WILL TANK LESS THAN 10 PERCENT
OVER MOST OF THE FORECAST AREA TODAY WITH THE FAR EASTERN PLAINS
NEAR TX BEING THE ONLY EXCEPTION. HIGHLY UNSTABLE AND WELL-MIXED
AIR MASS WOULD SEEM TO SUPPORT A GUSTY DAY FOR MUCH OF THE AREA...AND
BEST CONFIDENCE FOR CRITICAL WINDS EXTENDS ALONG AND EAST OF A
SOCORRO TO CLINES CORNERS TO RATON LINE...EXCLUDING SOME OF THE FAR
PLAINS ALONG THE OK/TX BORDERS. HAVE THROWN IN MIDDLE RIO GRANDE
FWZ106 TO THE WARNING. WOULD NOT BE SURPRISED TO SEE A COUPLE OF
STRAY GUSTS TO 35 MPH IN THE WEST CENTRAL ZONES...BUT CONFIDENCE IS
NOT HIGH ENOUGH TO PULL TRIGGER ON WARNING.
CONFIDENCE IS A BIT HIGHER ON MONDAY DUE TO STRONGER WIND SIGNALS
SUCH AS BETTER AGREEMENT ON THE SURFACE LOW PLACEMENT AND STRONGER
WINDS ALOFT OF 20 TO 35 KT IN THE H7-H5 LAYER. VERY DRY AIR MASS
ALOFT AND REINFORCEMENT FROM A MID LEVEL DRY SLOT WILL MAKE ANOTHER
EXTREMELY LOW RH REGIME WITH POOR RECOVERIES MONDAY MORNING AND
PROLONGED SINGLE DIGIT READINGS. HAVE EXTENDED WATCH FOR MONDAY TO
INCLUDE MIDDLE RIO GRANDE AND NORTHWESTERN AND WEST CENTRAL
HIGHLANDS/MOUNTAINS. HAVE LEFT NORTHERN MOUNTAINS AND NORTHWEST
PLATEAU OUT DUE TO LOWER CONFIDENCE IN THE WINDS...BUT THIS WILL
NEED TO BE SCRUTINIZED OVER THE NEXT 24 HOURS.
THE WINDS ALOFT DO RELAX SOME INTO TUESDAY AS THE UPPER HIGH BEGINS
TO DRIFT NORTHWARD. STILL...A SUFFICIENT LEE SIDE SURFACE LOW WILL
KEEP SOME BREEZY/WINDY CONDITIONS GOING IN THE EAST...PRIMARILY NEAR
THE I-40 CORRIDOR. INTO WEDNESDAY AND THROUGH THE REST OF THE WEEK
THE UPPER HIGH WILL ESTABLISH ITSELF OVER THE DESERT
SOUTHWEST...PERIODICALLY CENTERING NEAR OR CLOSE TO THE FOUR
CORNERS. THIS WILL SPELL DRY AND HOT CONDITIONS...BUT WITH LOW
WINDS. MOISTURE MAY FINALLY BEGIN TO ARRIVE FROM THE EAST BY THE
WEEKEND AS A BACK DOOR FRONT AND ONSHORE FLOW FROM THE GULF OF
MEXICO SEEP IN.
52
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR THE FOLLOWING
ZONES...NMZ102>104-106>108.
FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING FOR
THE FOLLOWING ZONES...NMZ102>109.
&&
$$
43/99
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
150 PM EDT SUN JUN 23 2013
.SYNOPSIS...
WE WILL CONTINUE OUR TREND OF A WARM AND INCREASINGLY HUMID
PATTERN. WEAK PASSING DISTURBANCES WILL RESULT IN SCATTERED
SHOWERS AND THUNDERSTORMS IN EACH OF THE NEXT SEVERAL DAYS...WITH
BEST CHANCES IN THE AFTERNOON HOURS.
&&
.NEAR TERM /THROUGH TONIGHT/...
115 PM UPDATE...
CONVECTION ACTIVELY DEVELOPING THIS HR ACROSS THE NORTHERN FINGER
LAKES IN LAKE PLAIN IN CLOSE PROXIMITY TO LAKE SHADOW BOUNDARY
WHICH NOW EXTENDS WELL INLAND FROM LAKE ERIE. FOR WHAT ITS
WORTH...RECENT HRRR RUNS HAVE BEEN SUGGESTING SUCH AN EVALUATION
AND ITS NICE TO SEE SHORT TERM HIGH-RES MODEL GUIDANCE ADDING
VALUE TO THE NEAR TERM FCST PERIOD. THAT SAID...LATEST SPC DAY-1
OUTLOOK PLACES THE NORTHERN HALF OF THE CWA IN A SLGT RISK FOR
SEVERE WITH STRONG WINDS BEING THE BIGGEST THREAT...LIKELY A
MANIFESTATION OF FAIRLY PRONOUNCED DRY AIR ALOFT AS EVIDENCED IN
VARIOUS 12Z RAOBS. LARGE HAIL ALSO A POSSIBILITY CONSIDERING THE
STRONG BUOYANCY ACROSS THE AREA WITH LATEST SPC MESO PAGE
SUGGESTING MLCAPE VALUES ON THE ORDER OF 2000-2500 J/KG ACROSS THE
AREA. WILL CONTINUE TO MONITOR.
950 AM UPDATE... FCST IN FAIRLY GOOD SHAPE THIS MORNING...ONLY
MINOR ADJUSTMENTS NEEDED TO ACCOUNT FOR LATEST TRENDS. THAT
SAID...MAIN FOCUS REMAINS CENTERED ON POSSIBLE CONVECTION LATER
THIS MORNING/AFTERNOON AS REGION WARMS WELL INTO THE THE MIDDLE TO
UPPER 80S IN A MODERATELY MOIST AND UNSTABLE ENVIRONMENT. LATEST
OBSERVATIONS ALREADY SHOWING SYR AT 85 THIS HR AND HAVE INCREASED
MAX TEMPS UPWARD A DEGREE OR TWO IN SOME LOCATIONS.
LATE MORNING WATER VAPOR IMAGERY SHOWING A FAIRLY WELL DEFINED
SHEAR AXIS LIFTING NORTH FROM SOUTHERN PENNSYLVANIA ALONG THE
NORTHERN PERIPHERY OF AN UPPER LOW THAT CONTINUES SPINNING THIS HR
ACROSS THE CENTRAL APPALACHIANS. RUC LAYERED 500-300 MB VORTICITY
SHOWS A SERIES OF EMBEDDED VORTICITY MAXIMA SLOWLY CREEPING NORTH
TOWARDS OUR AREA. THAT SAID...MAIN UPPER FORCING FOR ANY
CONVECTION LATER TODAY WILL LIKELY ARRIVE FROM THESE EMBEDDED FEATURES
WITH ADDITIONAL LOW-LEVEL FORCING POSSIBLY BEING SUPPLIED BY
INCREASED LOW-LEVEL CONVERGENCE ALONG A WEAK SURFACE TROUGH THAT
MODELS FCST TO MOVE THROUGH THE REGION LATER TODAY. LATEST HIGH
RES MODELS SUGGEST FAIRLY ISOLATED ACTIVITY DEVELOPING LATER TODAY
AND CONSIDERING THAT THE FORCING MECHANISMS ARE FAIR WEAK IN
NATURE...HAVE ELECTED TO TRIM BACK POPS INTO THE SCATTERED
CATEGORY GOING INTO THE AFTERNOON.
ABOVE SAID...12Z BUF RAOB SHOWING A FAIR AMOUNT OF DRY AIR ALOFT
WITH STEEP MID-LEVEL LAPSE RATES. CONSIDERING THE AMOUNT OF DRY
AIR ALOFT...IF ANY CONVECTION WERE TO DEVELOP...A FEW ROGUE PULSEY
TYPE SEVERE STORMS WITH LOCALLY HEAVY RAINS CANNOT BE RULED OUT
THANKS FOR WEAK WINDS ALOFT AND SLOW STORM MOVEMENT. WILL CONTINUE
TO MONITOR AND UPDATE AS NECESSARY.
645 AM UPDATE...
LATEST HIGH RES MODEL RUNS ARE COMING INTO GOOD AGREEMENT NOW ON
WAVE BEING ABLE TO INITIATE CONVECTION...INCLUDING THE
HRRR...RAP/RUC...AND WRFARW. OPERATIONAL 06Z NAM...00Z GEM...AND
EVEN SOMEWHAT THE 06Z GFS CONCUR ON AT LEAST THE GENERAL IDEA.
GRIDS HAVE BEEN UPDATED ACCORDINGLY WITH LARGER AREA OF MORE
DETERMINISTIC 60-70 PERCENT POPS FROM FINGER LAKES EASTWARD ACROSS
THE REMAINDER OF CENTRAL NY ESPECIALLY 18Z-22Z TIME FRAME. ALSO
HIGH CHANCE POPS SINKING INTO NORTHERN TIER OF PA 20Z SUN-01Z MON
TIME FRAME.
PREVIOUS DISCUSSION...
AFTER SEVERAL DRY DAYS...AREAS NORTH OF THE NEW YORK THRUWAY
FINALLY GOT SOME SCATTERED SHOWERS SATURDAY INTO OVERNIGHT DUE TO
THE INCREASINGLY MOIST AIR MASS...AND WEAK PASSING DISTURBANCES ON
THE SOUTHERN PERIPHERY OF THE BELT OF WESTERLIES. MORE OF THE AREA
WILL GET INVOLVED IN THAT TODAY...THOUGH BEST CHANCES WILL AGAIN
BE IN CENTRAL NEW YORK.
A LOOSELY DEFINED UPPER LOW IS CURRENTLY SPINNING ON THE KY/TN
BORDER...WHILE THE MAIN BELT OF WESTERLIES CARRIES OVER FROM THE
UPPER MIDWEST THROUGH THE NORTHERN GREAT LAKES AND INTO NEW
ENGLAND. BETWEEN THOSE FEATURES...AN UPPER RIDGE STILL EXTENDS
ACROSS THE MID-ATLANTIC STATES BACK TOWARDS THE UPPER OHIO VALLEY.
THE UPPER RIDGE IS LOSING ITS GRIP HOWEVER. MODELS DISAGREE ON HOW
QUICKLY MOISTURE FILLS THE VOID OF LOWER PRECIPITABLE WATER ALONG
THE RIDGE AXIS. IN ASSIGNING POPS TODAY...THE SREF APPEARS WAY
OVERDONE...AND UPSTREAM 00Z SUN SOUNDINGS IN BUFFALO NY AND WHITE
LAKE MI CONFIRM LOWER PRECIPITABLE WATER VALUES THAN SUGGESTED BY
SREF. THAT BEING SAID...THERE WILL DEFINITELY BE A GRADIENT IN
RAIN CHANCES. IT CAN BE CONFIDENTLY STATED THAT THE NORTHERN
ZONES WILL HAVE PWATS AT LEAST AROUND AN INCH-AND-TWO-
THIRDS...VERSUS THE SOUTHERN ZONES WHERE PWATS STAY UNDER AN
INCH-AND-A-HALF. IN BETWEEN...ACROSS THE TWIN TIERS...MODELS
DISAGREE ON AMOUNT OF MOISTURE AND THUS INSTABILITY.
AS A RESULT OF THE HIGHER PWATS...MODEL SOUNDINGS AGREE ON NORTHERN
ZONES HAVING MORE INSTABILITY...GREATER THAN 1000 J/KG...YET FARTHER
SOUTH IS MORE UNCERTAIN. ALSO...THE NORTHERN ZONES WILL BE MORE
PRONE TO SOME ALBEIT LIMITED FORCING FROM WEAK SHORTWAVES. I HAVE
KEYED IN ON WEAK VORTICITY WAVE THAT SHOWS UP ON GEM/NAM/WRFARW
MODELS WHICH WILL ENTER FINGER LAKES AROUND MIDDAY AND DRIFT
EASTWARD FROM THERE IN THE AFTERNOON...HIGH CHANCE TO LIKELY POPS.
RESULTANT CONVECTION WILL HAVE A FIGHT AS IT TRIES TO MAKE
SOUTHEAST PROGRESS...WITH LESS FRIENDLY AIR MASS...AND THUS LOWER
POPS. THOUGH THERE IS FAIR AMOUNT OF CONFIDENCE THAT THE
CONVECTIVE SHOWERS WILL CONTAIN THUNDER...SHEAR AND OTHER
PARAMETERS ARE LACKING AND THUS NOT EXPECTING ANY ORGANIZED
SEVERE THREAT. SPC DAY 1 CONVECTIVE OUTLOOK ONLY HAS A
BROAD-BRUSHED 5 PCT CHANCE OF SEVERE IN AN AXIS FROM LOWER MICHIGAN
THROUGH PARTS OF OUR REGION AND INTERIOR NEW ENGLAND.
MET AND MAV GUIDANCE WAS OVERALL JUST SLIGHTLY TOO WARM WITH
TEMPERATURES SATURDAY...AND I SUSPECT THE SAME MAY BE TRUE TODAY
CONSIDERING AMOUNT OF MOISTURE AND PROSPECTS FOR SCATTERED
CONVECTION. FOR HIGHS I BLENDED MAV/MET WITH THE SLIGHTLY COOLER
LAV GUIDANCE. STILL A WARM AND HUMID DAY...WITH HIGHS 80S AREA WIDE
AND EVEN SOME LOWER ELEVATION SPOTS NEAR 90. ANOTHER MUGGY NIGHT
TONIGHT WITH LOWS IN THE MID TO UPPER 60S.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
350 AM UPDATE...
LEFTOVERS OF UPPER LOW NOW OVER KY/TN BORDER...WILL DRIFT
NORTHWARD AROUND COLLAPSING UPPER RIDGE...AND CARRY THROUGH OUR
REGION MONDAY. DESPITE THAT LITTLE BIT OF ENERGY...PRECIPITABLE
WATER VALUES WILL ACTUALLY BE LOWERING THROUGH THE DAY. DIURNAL
HEATING AND MODEST INSTABILITY MOSTLY LESS THAN 1000 J/KG SHOULD
ALLOW FOR SCATTERED SHOWERS AND THUNDERSTORMS...WITH BEST CHANCES
GENERALLY FROM CENTRAL SOUTHERN TIER OF NY TO NEPA /THOUGH AT
LEAST SOME CHANCE AREA WIDE/.
COME TUESDAY...PRECIPITABLE WATER VALUES LOOK TO RETURN ABOVE 1.5
INCHES AND WE WILL ALSO AGAIN BE PENETRATED BY THE BELT OF
WESTERLIES AND EMBEDDED WAVES. UNCERTAINTY ON TIMING OF WAVES AND
MESOSCALE INFLUENCES PREVENTED ME FROM GOING HIGHER THAN 40-50 PCT
POPS...BUT AT LEAST SCATTERED DIURNALLY-DRIVEN CONVECTION LOOKS
LIKE A FAIR BET.
BOTH MONDAY AND TUESDAY...DAYTIME TEMPERATURES WILL REMAIN
ROUGHLY 6 TO 9 DEGREES ABOVE CLIMATOLOGY. DEW POINTS IN ABOUT THE
MID 60S MONDAY WILL SNEAK MORE INTO THE UPPER 60S TUESDAY...ALLOWING
HEAT INDICES TO ECLIPSE 90 AT LOWER ELEVATIONS. DESPITE THE HEAT AND
HUMIDITY...CAPES FAIRLY MODEST AND CONVECTIVE PARAMETERS SUCH AS
SHEAR ARE ONLY MARGINAL AT BEST...THUS OPPORTUNITY FOR AN
ORGANIZED SEVERE THREAT APPEARS QUITE LOW.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
A FLAT RIDGE WILL EXIST OVER MUCH OF THE EASTERN CONUS THIS
PERIOD. IMPULSES WILL ROTATE OVER THE TOP OF THE RIDGE, WHILE
WARM/MOIST AIR WILL REMAIN IN PLACE ACROSS NY/PA TYPIFIED BY 850MB
TEMPS OF 16C TO 20C.
THE RESULT WILL BE A MILD TEMPERATURE PATTERN, WITH THE DAILY
THREAT FOR ISOLATED TO SCATTERED THUNDERSTORMS. THE BEST CHANCE
FOR THUNDERSTORMS WILL BE ON THURSDAY, WHEN A TROF OVER SOUTHERN
CANADA DIPS ACROSS THE GREAT LAKES TOWARD LAKE ONTARIO.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
18Z SUN UPDATE... DVLPG SHRA/TSRA THIS AFTN MAY PROVIDE
RESTRICTIVE CONDS AT KSYR/KRME THROUGH ABT 20Z...AND PERHAPS IN
THE VICINITY OF KELM/KITH BY 20-22Z. FOR NOW...WE`LL LEAVE MENTION
OF ANY RESTRICTIONS OUT OF KBGM/KAVP OVER THE NEAR-TERM...AS TSRA
OCCURRENCES ARE MORE UNCERTAIN AT THESE LOCATIONS.
OVERNIGHT INTO MON AM...QUIET CONDS OVERALL...BUT SOME LGT FOG/HZ
COULD BRING MVFR RESTRICTIONS AT KRME/KITH/KBGM/KAVP AFTER 06Z...WITH
SOME LOCALLY DENSE VLY FOG STILL PSBL IN THE VICINITY OF KELM (IFR
CONDS).
SHRA/TSRA COULD DVLP AGN BY MON AFTN...BUT SCTD COVERAGE PRECLUDES
THEIR MENTION IN THE TERMINALS AT THIS EARLY JUNCTURE.
OUTLOOK...TUE THROUGH FRI...
RESTRICTIONS ARE PSBL EACH DAY...MAINLY IN THE AFTN/EVE...WITH AT
LEAST SCTD SHRA/TSRA FORESEEN. PATCHES OF OVERNIGHT/EARLY AM LOW
CLDS/FOG ARE ALSO PSBL.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...CMG/MDP
SHORT TERM...MDP
LONG TERM...DJP
AVIATION...MLJ
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
126 PM EDT SUN JUN 23 2013
.SYNOPSIS...
WE WILL CONTINUE OUR TREND OF A WARM AND INCREASINGLY HUMID
PATTERN. WEAK PASSING DISTURBANCES WILL RESULT IN SCATTERED
SHOWERS AND THUNDERSTORMS IN EACH OF THE NEXT SEVERAL DAYS...WITH
BEST CHANCES IN THE AFTERNOON HOURS.
&&
.NEAR TERM /THROUGH TONIGHT/...
115 PM UPDATE...
CONVECTION ACTIVELY DEVELOPING THIS HR ACROSS THE NORTHERN FINGER
LAKES IN LAKE PLAIN IN CLOSE PROXIMITY TO LAKE SHADOW BOUNDARY
WHICH NOW EXTENDS WELL INLAND FROM LAKE ERIE. FOR WHAT ITS
WORTH...RECENT HRRR RUNS HAVE BEEN SUGGESTING SUCH AN EVALUATION
AND ITS NICE TO SEE SHORT TERM HIGH-RES MODEL GUIDANCE ADDING
VALUE TO THE NEAR TERM FCST PERIOD. THAT SAID...LATEST SPC DAY-1
OUTLOOK PLACES THE NORTHERN HALF OF THE CWA IN A SLGT RISK FOR
SEVERE WITH STRONG WINDS BEING THE BIGGEST THREAT...LIKEY A
MANIFESTATION OF FAIRLY PRONOUNCED DRY AIR ALOFT AS EVIDENCED IN
VARIOUS 12Z RAOBS. LARGE HAIL ALSO A POSSIBILITY CONSIDERING THE
STRONG BUOYANCY ACROSS THE AREA WITH LATEST SPC MESO PAGE
SUGGESTING MLCAPE VALUES ON THE ORDER OF 2000-2500 J/KG ACROSS THE
AREA. WILL CONTINUE TO MONITOR.
950 AM UPDATE... FCST IN FAIRLY GOOD SHAPE THIS MORNING...ONLY
MINOR ADJUSTMENTS NEEDED TO ACCOUNT FOR LATEST TRENDS. THAT
SAID...MAIN FOCUS REMAINS CENTERED ON POSSIBLE CONVECTION LATER
THIS MORNING/AFTERNOON AS REGION WARMS WELL INTO THE THE MIDDLE TO
UPPER 80S IN A MODERATELY MOIST AND UNSTABLE ENVIRONMENT. LATEST
OBSERVATIONS ALREADY SHOWING SYR AT 85 THIS HR AND HAVE INCREASED
MAX TEMPS UPWARD A DEGREE OR TWO IN SOME LOCATIONS.
LATE MORNING WATER VAPOR IMAGERY SHOWING A FAIRLY WELL DEFINED
SHEAR AXIS LIFTING NORTH FROM SOUTHERN PENNSYLVANIA ALONG THE
NORTHERN PERIPHERY OF AN UPPER LOW THAT CONTINUES SPINNING THIS HR
ACROSS THE CENTRAL APPALACHIANS. RUC LAYERED 500-300 MB VORTICITY
SHOWS A SERIES OF EMBEDDED VORTICITY MAXIMA SLOWLY CREEPING NORTH
TOWARDS OUR AREA. THAT SAID...MAIN UPPER FORCING FOR ANY
CONVECTION LATER TODAY WILL LIKELY ARRIVE FROM THESE EMBEDDED FEATURES
WITH ADDITIONAL LOW-LEVEL FORCING POSSIBLY BEING SUPPLIED BY
INCREASED LOW-LEVEL CONVERGENCE ALONG A WEAK SURFACE TROUGH THAT
MODELS FCST TO MOVE THROUGH THE REGION LATER TODAY. LATEST HIGH
RES MODELS SUGGEST FAIRLY ISOLATED ACTIVITY DEVELOPING LATER TODAY
AND CONSIDERING THAT THE FORCING MECHANISMS ARE FAIR WEAK IN
NATURE...HAVE ELECTED TO TRIM BACK POPS INTO THE SCATTERED
CATEGORY GOING INTO THE AFTERNOON.
ABOVE SAID...12Z BUF RAOB SHOWING A FAIR AMOUNT OF DRY AIR ALOFT
WITH STEEP MID-LEVEL LAPSE RATES. CONSIDERING THE AMOUNT OF DRY
AIR ALOFT...IF ANY CONVECTION WERE TO DEVELOP...A FEW ROGUE PULSEY
TYPE SEVERE STORMS WITH LOCALLY HEAVY RAINS CANNOT BE RULED OUT
THANKS FOR WEAK WINDS ALOFT AND SLOW STORM MOVEMENT. WILL CONTINUE
TO MONITOR AND UPDATE AS NECESSARY.
645 AM UPDATE...
LATEST HIGH RES MODEL RUNS ARE COMING INTO GOOD AGREEMENT NOW ON
WAVE BEING ABLE TO INITIATE CONVECTION...INCLUDING THE
HRRR...RAP/RUC...AND WRFARW. OPERATIONAL 06Z NAM...00Z GEM...AND
EVEN SOMEWHAT THE 06Z GFS CONCUR ON AT LEAST THE GENERAL IDEA.
GRIDS HAVE BEEN UPDATED ACCORDINGLY WITH LARGER AREA OF MORE
DETERMINISTIC 60-70 PERCENT POPS FROM FINGER LAKES EASTWARD ACROSS
THE REMAINDER OF CENTRAL NY ESPECIALLY 18Z-22Z TIME FRAME. ALSO
HIGH CHANCE POPS SINKING INTO NORTHERN TIER OF PA 20Z SUN-01Z MON
TIME FRAME.
PREVIOUS DISCUSSION...
AFTER SEVERAL DRY DAYS...AREAS NORTH OF THE NEW YORK THRUWAY
FINALLY GOT SOME SCATTERED SHOWERS SATURDAY INTO OVERNIGHT DUE TO
THE INCREASINGLY MOIST AIR MASS...AND WEAK PASSING DISTURBANCES ON
THE SOUTHERN PERIPHERY OF THE BELT OF WESTERLIES. MORE OF THE AREA
WILL GET INVOLVED IN THAT TODAY...THOUGH BEST CHANCES WILL AGAIN
BE IN CENTRAL NEW YORK.
A LOOSELY DEFINED UPPER LOW IS CURRENTLY SPINNING ON THE KY/TN
BORDER...WHILE THE MAIN BELT OF WESTERLIES CARRIES OVER FROM THE
UPPER MIDWEST THROUGH THE NORTHERN GREAT LAKES AND INTO NEW
ENGLAND. BETWEEN THOSE FEATURES...AN UPPER RIDGE STILL EXTENDS
ACROSS THE MIDATLANTIC STATES BACK TOWARDS THE UPPER OHIO VALLEY.
THE UPPER RIDGE IS LOSING ITS GRIP HOWEVER. MODELS DISAGREE ON HOW
QUICKLY MOISTURE FILLS THE VOID OF LOWER PRECIPITABLE WATER ALONG
THE RIDGE AXIS. IN ASSIGNING POPS TODAY...THE SREF APPEARS WAY
OVERDONE...AND UPSTREAM 00Z SUN SOUNDINGS IN BUFFALO NY AND WHITE
LAKE MI CONFIRM LOWER PRECIPITABLE WATER VALUES THAN SUGGESTED BY
SREF. THAT BEING SAID...THERE WILL DEFINITELY BE A GRADIENT IN
RAIN CHANCES. IT CAN BE CONFIDENTLY STATED THAT THE NORTHERN
ZONES WILL HAVE PWATS AT LEAST AROUND AN INCH-AND-TWO-
THIRDS...VERSUS THE SOUTHERN ZONES WHERE PWATS STAY UNDER AN
INCH-AND-A-HALF. IN BETWEEN...ACROSS THE TWIN TIERS...MODELS
DISAGREE ON AMOUNT OF MOISTURE AND THUS INSTABILITY.
AS A RESULT OF THE HIGHER PWATS...MODEL SOUNDINGS AGREE ON NORTHERN
ZONES HAVING MORE INSTABILITY...GREATER THAN 1000 J/KG...YET FARTHER
SOUTH IS MORE UNCERTAIN. ALSO...THE NORTHERN ZONES WILL BE MORE
PRONE TO SOME ALBEIT LIMITED FORCING FROM WEAK SHORTWAVES. I HAVE
KEYED IN ON WEAK VORTICITY WAVE THAT SHOWS UP ON GEM/NAM/WRFARW
MODELS WHICH WILL ENTER FINGER LAKES AROUND MIDDAY AND DRIFT
EASTWARD FROM THERE IN THE AFTERNOON...HIGH CHANCE TO LIKELY POPS.
RESULTANT CONVECTION WILL HAVE A FIGHT AS IT TRIES TO MAKE
SOUTHEAST PROGRESS...WITH LESS FRIENDLY AIR MASS...AND THUS LOWER
POPS. THOUGH THERE IS FAIR AMOUNT OF CONFIDENCE THAT THE
CONVECTIVE SHOWERS WILL CONTAIN THUNDER...SHEAR AND OTHER
PARAMETERS ARE LACKING AND THUS NOT EXPECTING ANY ORGANIZED
SEVERE THREAT. SPC DAY 1 CONVECTIVE OUTLOOK ONLY HAS A
BROADBRUSHED 5 PCT CHANCE OF SEVERE IN AN AXIS FROM LOWER MICHIGAN
THROUGH PARTS OF OUR REGION AND INTERIOR NEW ENGLAND.
MET AND MAV GUIDANCE WAS OVERALL JUST SLIGHTLY TOO WARM WITH
TEMPERATURES SATURDAY...AND I SUSPECT THE SAME MAY BE TRUE TODAY
CONSIDERING AMOUNT OF MOISTURE AND PROSPECTS FOR SCATTERED
CONVECTION. FOR HIGHS I BLENDED MAV/MET WITH THE SLIGHTLY COOLER
LAV GUIDANCE. STILL A WARM AND HUMID DAY...WITH HIGHS 80S AREAWIDE
AND EVEN SOME LOWER ELEVATION SPOTS NEAR 90. ANOTHER MUGGY NIGHT
TONIGHT WITH LOWS IN THE MID TO UPPER 60S.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
350 AM UPDATE...
LEFTOVERS OF UPPER LOW NOW OVER KY/TN BORDER...WILL DRIFT
NORTHWARD AROUND COLLAPSING UPPER RIDGE...AND CARRY THROUGH OUR
REGION MONDAY. DESPITE THAT LITTLE BIT OF ENERGY...PRECIPITABLE
WATER VALUES WILL ACTUALLY BE LOWERING THROUGH THE DAY. DIURNAL
HEATING AND MODEST INSTABILITY MOSTLY LESS THAN 1000 J/KG SHOULD
ALLOW FOR SCATTERED SHOWERS AND THUNDERSTORMS...WITH BEST CHANCES
GENERALLY FROM CENTRAL SOUTHERN TIER OF NY TO NEPA /THOUGH AT
LEAST SOME CHANCE AREAWIDE/.
COME TUESDAY...PRECIPITABLE WATER VALUES LOOK TO RETURN ABOVE 1.5
INCHES AND WE WILL ALSO AGAIN BE PENETRATED BY THE BELT OF
WESTERLIES AND EMBEDDED WAVES. UNCERTAINTY ON TIMING OF WAVES AND
MESOSCALE INFLUENCES PREVENTED ME FROM GOING HIGHER THAN 40-50 PCT
POPS...BUT AT LEAST SCATTERED DIURNALLY-DRIVEN CONVECTION LOOKS
LIKE A FAIR BET.
BOTH MONDAY AND TUESDAY...DAYTIME TEMPERATURES WILL REMAIN
ROUGHLY 6 TO 9 DEGREES ABOVE CLIMATOLOGY. DEWPOINTS IN ABOUT THE
MID 60S MONDAY WILL SNEAK MORE INTO THE UPPER 60S TUESDAY...ALLOWING
HEAT INDICES TO ECLIPSE 90 AT LOWER ELEVATIONS. DESPITE THE HEAT AND
HUMIDITY...CAPES FAIRLY MODEST AND CONVECTIVE PARAMETERS SUCH AS
SHEAR ARE ONLY MARGINAL AT BEST...THUS OPPORTUNITY FOR AN
ORGANIZED SEVERE THREAT APPEARS QUITE LOW.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
A FLAT RIDGE WILL EXIST OVER MUCH OF THE EASTERN CONUS THIS
PERIOD. IMPULSES WILL ROTATE OVER THE TOP OF THE RIDGE, WHILE
WARM/MOIST AIR WILL REMAIN IN PLACE ACROSS NY/PA TYPIFIED BY 850MB
TEMPS OF 16C TO 20C.
THE RESULT WILL BE A MILD TEMPERATURE PATTERN, WITH THE DAILY
THREAT FOR ISOLATED TO SCATTERED THUNDERSTORMS. THE BEST CHANCE
FOR THUNDERSTORMS WILL BE ON THURSDAY, WHEN A TROF OVER SOUTHERN
CANADA DIPS ACROSS THE GREAT LAKES TOWARD LAKE ONTARIO.
&&
.AVIATION /17Z SUNDAY THROUGH THURSDAY/...
ATMOSPHERE WILL DESTABILIZE THIS AFTERNOON WITH CAPES PROJECTED AT
1000-2000 J/KG. A WEAK WAVE WILL DRIFT ACROSS THE REGION,
INCREASING THE POTENTIAL FOR THUNDERSTORM DEVELOPMENT. LATEST HRRR
CONCURS, BRINGING A LINE OF CONVECTION THROUGH CENTRAL NY BETWEEN
18Z AND 22Z.
WITH INCREASED CONFIDENCE FOR AFTERNOON CONVECTION...TAFS WILL NOW
INCLUDE TEMPO GROUPS FOR THUNDER AT THE NY TERMINALS.
OUTLOOK...MON 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...MDP
NEAR TERM...CMG/MDP
SHORT TERM...MDP
LONG TERM...DJP
AVIATION...DJP
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
314 PM CDT SUN JUN 23 2013
.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.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...JR
LONG TERM...JR/JK
AVIATION...JK
AREA FORECAST DISCUSSION
NWS BISMARCK ND
120 PM CDT SUN JUN 23 2013
.UPDATE...
ISSUED AT 120 PM CDT SUN JUN 23 2013
MAIN UPDATES EARLY THIS AFTERNOON WERE TO AGAIN MODIFY SKY COVER
AND PRECIP/THUNDER CHANCES BASED ON LATEST SATELLITE AND RADAR
IMAGERY. THERE REMAINS A CHANCE FOR ISOLATED
CONVECTION...SHOWERS OR WEAK THUNDERSTORMS...OVER MUCH OF THE WEST
AND CENTRAL THIS AFTERNOON...WITH THE BEST CHANCES NORTH CLOSE TO
THE UPPER TROUGH. TEMPERATURE ADJUSTMENTS FROM THE PREVIOUS UPDATE
STILL LOOKING GOOD.
UPDATE ISSUED AT 1050 AM CDT SUN JUN 23 2013
MAIN UPDATES WERE TO MODIFY SKY COVER AND PRECIP/THUNDER CHANCES
BASED ON LATEST SATELLITE AND RADAR IMAGERY. TEMPERATURES WERE
TRENDED DOWN A TAD NORTH TO ACCOUNT FOR EXTENSIVE CLOUD
COVER...WHICH IS EXPECTED TO PERSIST INTO THE AFTERNOON HOURS
LIMITING DAYTIME HEATING.
THERE REMAINS A CHANCE FOR ISOLATED CONVECTION...SHOWERS OR WEAK
THUNDERSTORMS...OVER MUCH OF THE WEST AND CENTRAL THIS AFTERNOON WITH
THE UPPER TROUGH OVER NORTH DAKOTA ALONG WITH SOME INSTABILITY
STILL PRESENT.
UPDATE ISSUED AT 639 AM CDT SUN JUN 23 2013
THERE WERE MINOR UPDATES TO ACCOUNT FOR THE LATEST SATELLITE AND
RADAR IMAGERY TRENDS. CYCLONIC FLOW ALOFT WILL HELP ERODE THE CAP
THIS AFTERNOON TO RELEASE WEAK CONVECTIVE INSTABILITY IN THE FORM
OF WEAK THUNDERSTORMS...AS INDICATED BY THE LAST SEVERAL RUNS OF
THE HRRR MODEL.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 320 AM CDT SUN JUN 23 2013
THE HIGHLIGHT OF THE SHORT TERM ARE CONVECTIVE CHANCES FOR TODAY.
CURRENTLY...WIDESPREAD LIGHT TO MODERATE RAIN WITH EMBEDDED
THUNDERSTORMS CONTINUES ACROSS MOST OF NORTHERN NORTH DAKOTA IN
ASSOCIATION WITH THE RIGHT ENTRANCE REGION OF THE UPPER LEVEL JET
STREAK AHEAD OF THE STRONG SHORTWAVE. AS THIS WAVE CONTINUES TO
PROPAGATE TO THE NORTHEAST THROUGH THE MORNING AND AFTERNOON...THE
AREA OF MORE WIDESPREAD PRECIPITATION ACROSS NORTHERN NORTH DAKOTA
WILL BECOME FOCUSED INTO MANITOBA. HOWEVER...WITH CLEARING SKIES
EXPECT SURFACE DESTABILIZATION AND THE DEVELOPMENT OF DIURNALLY
DRIVEN SCATTERED SHOWERS AND THUNDERSTORMS AS DEPICTED BY THE 00
UTC 4KM WRF AND THE 06 UTC HRRR AREA WIDE. DO NOT ANTICIPATE
WIDESPREAD SEVERE THUNDERSTORMS...HOWEVER...ML CAPE VALUES NEAR
1000 J/KG AND DEEP LAYER SHEAR OF 30-35 KTS SUGGEST THE POTENTIAL
FOR MARGINAL SEVERE HAIL WITH THE STRONGER STORMS. CONVECTION IS
EXPECTED TO QUICKLY FADE WITH SUNSET...WITH FOG POSSIBLE WITH
CLEAR SKIES AND LIGHT WINDS IN A WEAK SURFACE RIDGE AXIS TONIGHT.
DID CANCEL THE FLASH FLOOD WATCH THAT WAS IN EFFECT FOR THE JAMES
RIVER VALLEY AND PORTIONS OF FAR SOUTH CENTRAL NORTH DAKOTA. WHILE
SCATTERED THUNDERSTORMS ARE POSSIBLE TODAY...THE THREAT FOR FLASH
FLOODING IS NO LONGER ANTICIPATED. SEE THE HYDROLOGY DISCUSSION
FOR DETAILS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 320 AM CDT SUN JUN 23 2013
THE MAIN FOCUS TODAY IS ON THE POTENTIAL FOR STRONG/SEVERE
THUNDERSTORMS MONDAY THROUGH TUESDAY NIGHT.
ANOTHER LOW PRESSURE SYSTEM IS SCHEDULED TO MOVE ACROSS THE NORTHERN
PLAINS TUESDAY AS THE FOUR CORNERS MID/UPPER LEVEL RIDGE AND
NORTHEASTERN PACIFIC MID/UPPER LEVEL TROUGH MAINTAIN A BELT OF
WESTERLIES ACROSS THE NORTHERN ROCKIES AND DAKOTAS. THE 00 UTC
NAM/ECMWF/GFS/GEM GLOBAL ALL AGREE ON GENERAL TIMING OF THE
SYSTEM...BUT THERE IS SIGNIFICANT SPREAD ON THE TIMING/LOCATION OF
ASSOCIATED CONVECTION. THE UNCERTAINTY ASSOCIATED WITH COMPLEX
MESOSCALE INTERACTIONS IS LARGE...SO THERE IS NO EASY WAY TO PICK
THE SINGLE MODEL SOLUTION MOST LIKELY TO VERIFY. THUS...FORECASTS
USED A CONSENSUS BLEND OF ALL AVAILABLE UTC MODELS/ENSEMBLES.
THE STORM PREDICTION CENTER FORECAST FROM THEIR OUTLOOKS CALLS
FOR LATE AFTERNOON CONVECTION ALONG THE MT/ND BORDER LOOKS TO FORM
AN MCS THAT PROPAGATES INTO THE CENTRAL PLAINS ON MONDAY NIGHT.
CONVECTION LOOKS TO REGENERATE OVER CENTRAL NORTH DAKOTA ON TUESDAY
FOR ANOTHER ROUND IN CENTRAL AND EASTERN COUNTIES.
THEREAFTER...00 UTC MODELS/ENSEMBLES GENERALLY AGREE ON A MORE
DIURNAL NATURE FOR THE ISOLATED CONVECTION THAT DOES INITIATE AMIDST
STRONGER RIDGING ALOFT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 120 PM CDT SUN JUN 23 2013
WILL MAINTAIN VCSH OR VCTS FOR ALL BUT KDIK THROUGH 00Z EARLY
THIS EVENING. SCT-BKN MVFR CU CONTINUES TO DEVELOP AND SPREAD
EAST ACROSS THE SOUTHERN TERMINALS AS SKIES CLEAR. BEST CHANCE FOR
SHOWERS AND ISOLATED THUNDERSTORMS NORTH CENTRAL AT KMOT NEAR AN
UPPER LEVEL LOW PRESSURE SYSTEM. SKIES WILL TREND VFR ALL
LOCATIONS BY EARLY THIS EVENING AND PERSIST THROUGH 18Z MONDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...AYD
LONG TERM...SCHECK
AVIATION...NH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1252 PM CDT SUN JUN 23 2013
.UPDATE...
ISSUED AT 1252 PM CDT SUN JUN 23 2013
ADJUSTED POPS AGAIN FOR CURRENT RADAR TRENDS AS THE MAIN RAIN BAND
LIFTS FURTHER NORTH...BUT EXPECT SOME REDEVELOPMENT MAINLY OVER
THE NORTHERN CWA AS THE MAIN UPPER SYSTEM COMES OUT AND WITH A BIT
OF HEATING...SO KEPT POPS HIGH OVER THE NORTHERN COUNTIES THROUGH
THIS EVENING. WILL HAVE TO WATCH HOW MUCH CLEARING WE CAN GET THIS
AFTERNOON IN ORDER TO DESTABILIZE AS THE BETTER SHEAR STARTS TO
MOVE INTO THE AREA IN ORDER TO GET ANY SEVERE. LOWERED TEMPS A BIT
IN SOME AREAS AS SOME LOCATIONS HAVE STAYED CLOUDY AND RAINY AND
WILL ONLY RECOVER UP INTO THE UPPER 60S TODAY.
UPDATE ISSUED AT 1007 AM CDT SUN JUN 23 2013
MADE SOME ADJUSTMENTS TO POPS FOR CURRENT RADAR TRENDS. THE PRECIP
HAS LIFTED OUT OF OUR SOUTHERN COUNTIES AS DRY AIR HAS MOVED
IN...AND THAT AREA SHOULD SEE SOME CLEARING LATER ON TODAY.
FURTHER NORTH...THERE IS STILL A LOT OF MOISTURE CONVERGENCE AND
PRECIP REDEVELOPMENT ALONG THE NORTHERN END OF THE SFC TROUGH
AXIS/FRONTAL BOUNDARY FROM DEVILS LAKE TOWARDS MAYVILLE. MORE
SHOWERS AND STORMS HAVE DEVELOPED IN THE NORTHEASTERN COUNTIES
ALSO AND THINK THAT DEVELOPMENT SHOULD CONTINUE THROUGH MUCH OF
THE DAY AS THE MAIN UPPER LOW KICKS SLOWLY OUT. SEVERITY LATER ON
WILL DEPEND ON DESTABILIZATION...BUT WILL HAVE TO WATCH THE NORTH
FOR ANYTHING GOING UNDER THE MAIN UPPER LOW.
UPDATE ISSUED AT 655 AM CDT SUN JUN 23 2013
AN AREA OF SHOWERS AND EMBEDDED THUNDER CONTINUES TO MOVE SLOWLY
NORTH THIS MORNING. EXPECT A SLOW WEAKENING TREND FOR A FEW
HOURS...BEFORE ACTIVITY INCREASES LATER THIS MORNING AND EARLY
AFTERNOON. NO MAJOR CHANGES TO THE FORECAST WITH THIS UPDATE.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 345 AM CDT SUN JUN 23 2013
THE MAIN CHALLENGE THIS MORNING WILL BE SEVERE STORM THREAT TODAY
AND MORE STORMS POSSIBLE MON NIGHT AND TUE. MODELS ARE IN GOOD
OVERALL AGREEMENT...AND WILL FOLLOW THE HRRR INITIALLY THEN SIDE
WITH THE CONSISTENT GFS.
FOR TODAY...EXPECT AN MCS TO BE ONGOING THIS MORNING MOVING FROM
SW TO NE. THERE COULD BE LOCALLY HEAVY RAINFALL THIS MORNING IN
THE SOUTH...AND THIS AREA IS QUITE SATURATED SO WILL CONTINUE WITH
THE FLASH FLOOD WARNING UNTIL 12Z. THERE COULD BE A MORE ORGANIZED
SEVERE THREAT BY EARLY AFTERNOON MAINLY IN THE MN COUNTIES ALONG A
COLD FRONT...MLCAPE TO AROUND 2000 J/KG AND AMPLE DEEP LAYERED
SHEAR. THE MAIN THREATS SHOULD BE LARGE HAIL AND DAMAGING WINDS.
FOR TONIGHT...ANY CONVECTION SHOULD QUICKLY MOVE OUT OF THE
EASTERN AREAS DURING THE EVENING. DRIER AIR WILL ADVECT INTO THE
REGION WITH GENERAL LIGHT WINDS. WILL HAVE TO WATCH FOR PATCHY FOG
IN AREAS THAT GET RAIN...BUT FOR NOW WON/T MENTION WITH AREAL
COVERAGE NOT CERTAIN.
ON MONDAY...EXPECT A DRY AND WARM DAY WITH 850MB TEMPS WARMING TO
AROUND +18C. MOISTURE PROFILES WILL BEGIN TO INCREASE BY AFTERNOON
IN THE WEST AHEAD OF THE NEXT SHORTWAVE.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 345 AM CDT SUN JUN 23 2013
FOR MONDAY NIGHT AND TUE...THE THREAT FOR SHOWERS AND STORMS WILL
ONCE AGAIN INCREASE WITH SHORTWAVE ENERGY MOVING THROUGH GENERAL
SW FLOW ALOFT. TIMING STILL REMAINS A QUESTION...BUT THE SEVERE
THREAT COULD ALSO INCREASE AT LEAST IN THE WEST ON TUE...AND WILL
FEEL LIKE SUMMER WITH TEMPS ABOVE NORMAL AND PLENTY OF MOISTURE IN
PLACE.
FOR WEDNESDAY THROUGH SATURDAY...A LONG WAVE TROUGH AXIS DEVELOPS
OVER THE EASTERN PACIFIC AND THE EASTERN US WHILE A LONG WAVE
RIDGE DEVELOPS OVER THE NORTHERN ROCKIES AND INTO THE CANADIAN
ROCKIES. PATTERN BECOMES MORE NORTHWEST FLOW ALOFT WITH TIME.
ECMWF BEGINS THE PERIOD AS A FASTER SOLUTION THAN THE GFS. THE ECMWF
MAINTAINS A CONSISTENT FAST BIAS THROUGH THE PERIOD. THE ECMWF HAS
TRENDED WITH FASTER SOLUTIONS OVER THE LAST FEW MODEL RUNS WHILE
THE GFS HAS TRENDED SLOWER. WILL BLEND THE TWO MODELS AND WILL SPEED
UP PRECIPITATION A BIT FROM TODAYS RUN AND MAY KEEP YESTERDAYS RUN
WITH SOME TIME PERIODS.
LITTLE CHANGE TO TEMPS THIS PERIOD FROM YESTERDAYS RUN.
&&
.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 1252 PM CDT SUN JUN 23 2013
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.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...DK
LONG TERM...HOPPES/DK
AVIATION...JK
HYDROLOGY...JK
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1254 PM CDT SUN JUN 23 2013
.UPDATE...FOR 18Z TAFS.
&&
.AVIATION...
WEAK UPPER LOW JUST EAST OF THE PLATEAU EXPECTED TO TRANSITION
INTO AN UPPER TROUGH OVER THE NEXT 24HRS. THIS WILL CONTINUE
TO FOCUS CONVECTION CSV VICINITY INTO THE EVENING...WITH VERY
LITTLE CHANCE BNA/CKV. BOUNDARY LAYER MOISTURE MORE ABUNDANT AS
WELL WHICH COULD LEAD TO MVFR FOG OVERNIGHT BNA/CKV...WITH
CEILINGS/VSBYS EVEN LOWER CSV. CONDITIONS WILL IMPROVE RAPIDLY
13-14Z MONDAY.
&&
.PREV DISCUSSION... /ISSUED 1036 AM CDT SUN JUN 23 2013/
UPDATE...CELLS ARE ALREADY POPPING UP ALONG THE CUMBERLAND
PLATEAU, WHERE SURFACE HUMIDITIES ARE HIGHEST. HRRR APPEARS TO
HAVE A GOOD HANDLE ON THE CURRENT ACTIVITY, AND IT SUGGESTS
NOTHING MORE THAN ISOLATED CONVECTION FOR THE REMAINDER OF MIDDLE
TENNESSEE FOR THE AFTERNOON. SO WILL GO AHEAD AN INCREASE POP`S
ALONG THE PLATEAU FOR THE REST OF TODAY AND LEAVE ISOLATED IN FOR
EVERYONE ELSE.
PREV DISCUSSION... /ISSUED 627 AM CDT SUN JUN 23 2013/
AVIATION...
AFTER LOCAL 4SM BR DISSIPATES EXPECT VFR CONDITIONS AT ALL THREE
TAF SITES THROUGH THE TAF PERIOD...UNLESS IMPACTED BY A STRONG
STORM THEN MVFR VIS MAY BE RESULT IN A BRIEF DOWNPOUR. EXPECT
THE DIURNLAL CU THAT HAS BEEN IMPACTING MIDDLE TENNESSEE OVER THE
LAST FEW DAYS TO REDEVELOP AGAIN TODAY AFTER 16Z THIS MORNING...THEN
DISSIPATE SOMETIME AFTER 00Z. ISOLATED CHANCES AT BEST FOR STRONG
STORMS.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07
AREA FORECAST DISCUSSION
NWS AMARILLO TX
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
&&
.PRELIMINARY POINT TEMPS/POPS...
AMARILLO TX 97 68 95 68 98 / 20 5 5 5 0
BEAVER OK 98 71 97 72 99 / 10 20 20 20 0
BOISE CITY OK 100 65 100 68 101 / 10 10 5 5 0
BORGER TX 99 70 96 71 99 / 20 10 10 10 0
BOYS RANCH TX 100 70 98 68 102 / 20 5 5 5 0
CANYON TX 98 68 96 68 98 / 20 5 10 10 0
CLARENDON TX 96 68 94 70 96 / 20 20 20 20 0
DALHART TX 101 64 101 64 102 / 10 5 5 5 0
GUYMON OK 99 69 99 68 100 / 10 5 10 10 0
HEREFORD TX 99 67 94 66 98 / 20 5 5 5 0
LIPSCOMB TX 96 71 96 73 99 / 20 20 20 20 0
PAMPA TX 95 68 94 69 98 / 20 20 20 20 0
SHAMROCK TX 97 70 95 72 99 / 10 20 20 20 0
WELLINGTON TX 99 71 97 72 97 / 10 20 20 20 0
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
03/16
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
344 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 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1230 PM CDT SUN JUN 23 2013
TSRA SHOULD REMAIN SOUTH OF THE TAF SITES THROUGH THE PERIOD. HAVE
REMOVED THE TSRA CHANCES IN THE TAFS...BUT WILL KEEP A CLOSE EYE
ON ADDING THESE BACK. IT APPEARS A VFR PERIOD IS WARRANTED.
&&
.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 THROUGH MONDAY MORNING FOR WIZ041>044-053>055-
061.
MN...FLASH FLOOD WATCH THROUGH MONDAY MORNING FOR MNZ096.
IA...FLASH FLOOD WATCH THROUGH MONDAY 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
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.
&&
$$
TONIGHT/MONDAY AND AVIATION/MARINE...COLLAR
MONDAY NIGHT THROUGH SUNDAY...REM
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST 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 18Z TAF ISSUANCE
ISSUED AT 1240 PM CDT SUN JUN 23 2013
A WEAK FRONT WILL PASS ACROSS THE REGION THIS AFTERNOON. WITH
CONTINUED HEATING...STORMS SHOULD REDEVELOP ALONG THIS
FRONT...THOUGH EXACT TIMING/IMPACT IS STILL UNCERTAIN. INSTABILITY
HAS BEEN SLOW TO BUILD THIS MORNING...SO THINKING THIS MAY BE A MID
TO LATE AFTERNOON THING...WHICH COULD ENTIRELY MISS THE CENTRAL AND
NORTH-CENTRAL WISCONSIN TAF SITES. DUE TO THE UNCERTAINTY...WILL
LEAVE ANY MENTION OF THUNDER OUT OF THOSE TAF SITES. BETTER CHANCES
APPEAR TO OCCUR OVER THE FOX VALLEY AND LAKE SHORE LATE THIS
AFTERNOON...SO HAVE ADDED A TEMPO GROUP. BEHIND THE FRONT...MVFR
CLOUD DECK WILL LIKELY IMPACT N-C WISCONSIN TONIGHT. VSBYS TO ALL
FALL INTO THE MVFR RANGE LATE TONIGHT WITH THE HUMID AIRMASS IN
PLACE. LOOKING LIKE GOOD FLYING WEATHER TOMORROW AT THE MOMENT.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......MPC