Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 05/16/13
AREA FORECAST DISCUSSION
NWS TUCSON AZ
235 AM MST TUE MAY 14 2013
.SYNOPSIS...A WEAK LOW IN NORTHERN MEXICO WILL PUSH NORTHEAST
THROUGH THE AREA TODAY...WITH A CHANCE OF MAINLY MOUNTAIN
THUNDERSTORMS THIS AFTERNOON AND EVENING. OTHERWISE...TEMPERATURES
WILL CONTINUE TO HEAT UP DURING THE WORK WEEK WITH HIGHS NEAR 100
DEGREES IN THE LOWER DESERT LOCATIONS AND 90S ELSEWHERE. A STRONGER
SYSTEM WILL MOVE NORTH OF THE REGION THIS COMING WEEKEND...RESULTING
IN SEVERAL DEGREES OF COOLING AND BREEZY CONDITIONS.
&&
.DISCUSSION...SOME MID CLOUD ENHANCEMENT THIS MORNING ON THE
NORTHERN PERIPHERY OF THE WEAKENING LOW IN NORTHWEST MEXICO. A FEW
SPRINKLES REACHING THE GROUND UNDER MOSTLY VIRGA EARLY THIS MORNING.
SOME BOUNDARY LAYER MOISTURE INCREASE UNDER THE MID LEVEL
MOISTURE...AS THE LOW SHEARS INTO NEW MEXICO ON IT`S WAY TO HIGHER
LATITUDES OVER THE NEXT 12 TO 24 HOURS. WE SHOULD MANAGE ENOUGH
INSTABILITY FOR UNSEASONABLE MODERATE CONVECTIVE DEVELOPMENT OVER
THE MOUNTAINS AS REFLECTED BY LATEST HRRR AND NAMDNG5 TRENDS. LATEST
RAPID REFRESH AND PREVIOUS UOFAZ WRF OUTPUT SUGGEST DEVELOPING 250
TO 400 VALLEY CAPE THIS AFTERNOON. COMBINED WITH A LESS FAVORABLE
FLOW WE STILL DON`T EXPECT TO BE ABLE TO SUPPORT MUCH CONVECTION IN
MOST VALLEY LOCATIONS...HOWEVER SOME ORGANIZED OUTFLOW FROM
COLLAPSING STORMS AS THEY TRY TO PUSH INTO VALLEYS EXPECTED AND FEW
HUNDREDTHS HERE AND THERE NOT OUT OF THE QUESTION.
THE RIDGE CLEANS UP A BIT AS THIS WEAKNESS KICKS WELL NORTHEAST
TONIGHT...BUT LOSES GEOMETRY AS THE AXIS SHIFTS EAST OF US THURSDAY
WITH A DEVELOPING SYSTEM NEAR THE PACIFIC NORTHWEST. AFTER A PAUSE
IN THE HEATING TREND TODAY...WE`LL HAVE TIME TO JUMP BACK INTO
HOTTER TEMPERATURES WEDNESDAY AND THURSDAY BUT STILL HAVING A HARD
TIME JUSTIFYING THE FIRST 100 AT TIA...98 OR 99 IS ABOUT ALL WE CAN
CURRENTLY SQUEEZE OUT OF THE FORECASTED THICKNESS AND HEIGHT TRENDS.
TROUGH PUSHING THROUGH THE REGION FRIDAY INTO THE WEEKEND. AS ONE
MIGHT EXPECT FOR THE SECOND HALF OF MAY...DYNAMICS AND BEST MOISTURE
WELL NORTH OF OUR CWA BUT WE CAN EXPECT A MODEST COOLING TREND AND
GUSTY WINDS OUT OF THE SYSTEM.
WEAKENING RIDGE PHASING ACROSS THE AREA EARLY NEXT WEEK COULD BRING
THE FIRST 100 FOR TIA MONDAY OR TUESDAY IF WE CAN`T MANAGE IT THIS
WEEK.
&&
.AVIATION...SKC-SCT 12KFT AGL LCL BKN 10KFT AGL WITH ISOLD -SHRA.
FROM 14/20Z THRU 15/04Z SCT-BKN 12KFT WDLY SCTD -SHRA/TS BKN 8KFT
AGL...MAINLY E AND S OF KTUS. AFT 15/04Z...FEW-SCT LCLY BKN 10KFT
AGL. SFC WIND E-S 5-10 KTS WITH LCL GUSTS TO 18 KTS...FROM 14/19Z
THRU 15/04Z SFC WND W-S 8-15 KTS WITH OCNL GUSTS 18-24 KTS...HIGHER
GUSTS NR SHRA/TS E AND S OF KTUS...AFT 15/04Z WIND TERRAIN DRIVEN
LESS THAN 10 KTS. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...A WEAK UPPER LOW OVER NORTHERN MEXICO WILL MOVE
NORTHEAST TODAY INTO THIS EVENING. ENOUGH MOISTURE IS AROUND FOR THE
DEVELOPMENT OF ISOLATED SHOWERS...POSSIBLY A THUNDERSTORM...FROM
TUCSON EAST AND SOUTH. WEAK RIDGE OF HIGH PRESSURE OVER THE AREA
WEDNESDAY AND THURSDAY BEFORE AN UPPER LEVEL TROUGH MOVES THROUGH
THE INTERMOUNTAIN WEST FRIDAY AND SATURDAY BRINGING BREEZY TO
LOCALLY WINDY CONDITIONS TO THE REGION.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
MEYER/GLUECK
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
932 AM MDT TUE MAY 14 2013
.UPDATE...OVERALL JUST MINOR ADJUSTMENTS TO THE GRIDS TODAY. MDLS
INDICATE MORE OF AN INVERTED PROFILE WITH THE SOUNDINGS THIS
AFTERNOON AS THE LOW LEVEL MOISTURE MIXES OUT...SO LIGHT RAINFALL
AND GUSTY OUTFLOW WINDS THE MAIN PRODUCTS OF THESE STORMS. ISOLD
COVERAGE EAST OF I-25 SHOULD NOT BECOME A REALITY UNTIL THIS
EVENING. HRRR INDICATES THE BEST TSTM COVERAGE THIS AFTN WILL BE
ALONG THE PALMER DIVIDE. FCST CAPES AROUND 500 J/KG...WITH
TEMPERATURES LIKELY EQUALING OR EXCEEDING OUR RECORD HIGH IN
DENVER FOR THIS DATE. WEAK FRONTAL BOUNDARY SHOULD BACK ITS WAY
INTO THE CWFA THIS EVENING.
&&
.AVIATION...NO BIG ADJUSTMENTS PLANNED AT THIS TIME. GUSTY OUTFLOW
WINDS THE PRIMARY ISSUE WITH THE TSTMS THIS AFTN SO ADDED TEMPO
PERIOD IN THE 23-01Z TIME FRAME TO REFLECT THIS...OTHERWISE THE
REST OF THE TAF LOOKS ON TRACK.
&&
.PREV DISCUSSION... /ISSUED 356 AM MDT TUE MAY 14 2013/
SHORT TERM...A FLAT UPPER LEVEL RIDGE WILL BE OVER THE AREA THRU
TONIGHT WITH WEAK FLOW ALOFT. AT THE SURFACE THERE WILL BE A WK
BNDRY MOVING ACROSS NERN CO BY MIDDAY WITH LOW LVL WINDS BECOMING
NNE BY MIDDAY AND THEN MORE ELY BY LATE AFTN. OVERALL INSTABILITY
IS NOT THAT GREAT BASED ON CURRENT SOUNDINGS WITH CAPES UNDER 500
J/KG. HOWEVER WITH SOME INCREASE IN MID LEVEL MOISTURE WILL SEE
SOME HIGH BASED STORMS OVER THE HIGHER TERRAIN THIS AFTN. OVER
NERN CO THE NAM SHOWS SOME ISOLD TO WDLY SCT CONVECTION BY 21Z
WHILE GFS KEEPS ALL OF THE ACTIVITY IN THE FOOTHILLS AND MTNS THRU
00Z. FOR NOW WILL JUST KEEP SOME LOW POPS ALONG THE FRONT RANGE AND
ACROSS THE PALMER DIVIDE IN THE 21Z-00Z TIME PERIOD. AS FOR HIGHS
WK BNDRY MOVING ACROSS NERN CO DOES NOT HAVE ANY COOL AIR SO WITH
LITTLE CHANGE TO 850-700 MB TEMPS HIGHS SHOULD BE SIMILAR TO MON.
RECORD HIGH AT DENVER IS 87 WHICH COULD BE TIED OR BKN.
FOR TONIGHT THE NAM AND GFS INCREASE THE LOW LEVEL MOISTURE
ACROSS NERN CO THIS EVENING AS A COOL FNT MOVES INTO THE AREA.
THE GFS BLOWS UP CONVECTION IN THE 00Z-06Z TIMEFRAME OVER NERN CO
WHILE THE NAM HAS FAR LESS ACTIVITY AS WELL AS THE ECMWF. FOR NOW
WILL TREND MORE TOWARDS THE NAM AND ECMWF AND KEEP A SLIGHT CHC
ACROSS THE PLAINS.
LONG TERM...GENERALLY SPEAKING...THE NEXT WEEK OF WEATHER WILL
PRIMARILY BE ISOLATED-SCATTERED AFTERNOON CONVECTION OVER THE
MOUNTAINS AND A SLIGHT CHANCE OF AFTERNOON OR EVENING SHOWERS ON
THE PLAINS. WHEN LOOKING AT THE DETAILS...WEDNESDAY AFTERNOON WILL
FEATURE A SPLIT IN THE UPPER FLOW...THURSDAY WILL HAVE INCREASING
SOUTHWEST FLOW ALOFT...WHILE FRIDAY NIGHT AND SATURDAY FEATURE A
BROAD UPPER TROUGH MOVING OVER THE STATE. NONE OF THESE PATTERNS
LOOKS LIKE THEY WILL HAVE THE STRENGTH TO GENERATE SIGNIFICANT
SHOWER ACTIVITY...BUT UNCERTAINTY EXISTS OVER HOW MUCH LOW LEVEL
MOISTURE WILL ADVECT INTO THE REGION WHILE A SURFACE LOW RESIDES
OVER EASTERN COLORADO FROM WEDNESDAY THROUGH SATURDAY.
THEREFORE...WILL NOT MAKE ANY BIG CHANGES TO THE PREVIOUS
FORECAST. IT STILL LOOKS LIKE THURSDAY...FRIDAY AND SATURDAY WILL
BE WARMER THAN NORMAL BEFORE A COOL SURGE MOVES IN SATURDAY NIGHT
CAUSING COOLER TEMPERATURES ON SUNDAY AND MONDAY. AT THAT
TIME...THE ECMWF AND GFS INDICATE THERE WILL ALSO BE A BROAD UPPER
TROUGH OVER THE STATE WHICH MAY HELP ORGANIZE SOME SHOWER
ACTIVITY...ASSUMING ENOUGH MOISTURE IS PRESENT TO FEED INTO THE
DEVELOPING CONVECTION. SATURDAY EVENING COULD ALSO BE A LITTLE BIT
BREEZY AROUND THE PASSAGE OF THE UPPER TROUGH AXIS.
AVIATION...DRAINAGE WINDS EARLY THIS MORNING WILL BECOME LIGHT
NWLY BY 16Z AND THEN MORE NLY BY 18Z. BY 21Z WINDS WILL BECOME
MORE ENE WITH SPEEDS AROUND 10 MPH AND THEN ELY BY 00Z. THERE
COULD BE ISOLD HIGH BASED TSTMS MAINLY AFTER 23Z WHICH COULD
PRODUCE SOME VARIABLE GUSTY WINDS FOR A BRIEF PERIOD OF TIME. AT
THIS TIME WILL JUST MENTION VCTS IN THE 23Z-03Z TIME PERIOD. WINDS
EARLY THIS EVENING WILL BECOME MORE SELY AND THEN MAY TREND MORE
SWLY AFTER 03Z. A COOL FRONT MAY AFFECT THE AIRPORT BY 12Z WED
WITH WINDS BECOMING MORE NLY.
HYDROLOGY...RAINFALL AMOUNTS WILL BE UNDER ONE QUARTER INCH SO NO
ISSUES ARE EXPECTED.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...COOPER
LONG TERM....DANKERS
AVIATION...COOPER
AREA FORECAST DISCUSSION
NWS TAUNTON MA
705 PM EDT TUE MAY 14 2013
.SYNOPSIS...
COOL CONDITIONS WILL PERSIST TONIGHT AS A HIGH PRESSURE RIDGE
BUILDS ACROSS NEW ENGLAND. A WARM FRONT WILL APPROACH...BRINGING
SHOWERS INTO THE REGION WEDNESDAY AFTERNOON AND NIGHT. HIGH
PRESSURE BUILDS SOUTH FROM CANADA WITH DRY WEATHER AND SEASONABLE
TEMPERATURES FOR MOST OF THURSDAY THROUGH NEXT TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
7 PM UPDATE...
CLOUDS IN PLACE OVER SOUTHERN NEW ENGLAND MOVING SOUTHEAST.
CONTINUE TO EXPECT THEM TO DIMINISH/DISSIPATE AFTER SUNSET. RADAR
SHOWS LIGHT SHOWERS...MOSTLY MOVING OFF THE COASTS OF MAINE AND NH
AND PASSING JUST EAST OF CAPE ANN.
NO CHANGES IN FORECAST THINKING. ADJUSTED TEMPS AND WINDS TOWARD
OBSERVED VALUES AND PROJECTED THE NEXT FEW HOURS USING A BLEND OF
THE GLAMP AND HRRR MODELS.
PREVIOUS DISCUSSION...
HIGH PRES RIDGE WILL BUILD OUT OF NY STATE ACROSS NEW ENGLAND
TONIGHT...BRINGING DIMINISHING WINDS. HOWEVER...APPEARS THERE WILL
BE JUST ENOUGH WIND THROUGH MOST OF THE NIGHT ESPECIALLY ACROSS
CENTRAL AND EASTERN AREAS TO ESCAPE A LONG FROST. MAY SEE PATCHY
FROST FOR AN HOUR OR TWO AFTER 06Z ACROSS THESE AREAS. BEST SHOT
OF PATCHY FROST WILL OCCUR ACROSS S NH/N CENTRAL AND NW MA...WHERE
THE GROWING SEASON HAS NOT BEGUN YET.
EXPECT OVERNIGHT LOWS IN THE MID TO UPPER 30S ACROSS THE NORMALLY
COLDER INLAND LOCATIONS...RANGING TO THE MID 40S ALONG THE
IMMEDIATE COAST.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
WEDNESDAY...
UPPER LEVEL PATTERN REMAINS PROGRESSIVE ACROSS THE LOWER 48...SO
EXPECT NEXT DISTURBANCE TO WORK OUT OF THE GREAT LAKES DURING WED.
WILL SEE CLOUDS INCREASE STEADILY DURING THE DAY WITH THE APPROACH
OF A WARM FRONT. SHOWERS WILL MOVE INTO THE CT VALLEY IN THE
AFTERNOON AND MOVE STEADILY E. MAY HAVE MARGINAL INSTABILITY...
WITH TOTAL TOTALS FROM 48 TO 50 MOVING ACROSS SOUTHERN AREAS.
HAVE MENTIONED ISOLD THUNDER THERE...BUT LOW CONFIDENCE ON THIS
ASPECT. TOTAL QFP WILL BE AROUND 0.25 INCHES...BUT CAN NOT RULE
OUT LOCALIZED SPOTTY DOWNPOURS.
AS WARM FRONT PASSES...S-SW WINDS WILL PICK UP WITH GUSTS UP TO
20-25 KT FROM AROUND 18Z INTO THE EVENING...HIGHEST ALONG THE S
COAST.
EXPECT HIGHS IN THE 60S...EXCEPT THE MID-UPPER 50S ALONG THE S
COAST.
WEDNESDAY NIGHT...
TRAILING COLD FRONT WILL STEADILY MOVE ACROSS THE REGION EARLY.
SHOWERS SHOULD PUSH E AFTER MIDNIGHT...EXITING THE CAPE AND
ISLANDS BY 10Z OR SO. WINDS WILL SHIFT TO W AND DIMINISH. WITH
CLOUDS LINGERING...EXPECT TEMPS TO ONLY FALL BACK TO THE MID 40S
TO LOWER 50S.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
BIG PICTURE...
UPPER TROUGH OVER NEW ENGLAND AND THE MARITIMES LATE WEEK AND
OVER THE WEEKEND. UPPER RIDGE BUILDS ON MONDAY-TUESDAY.
MODEL PREFERENCES...
MODEL MASS FIELDS THIS SIDE OF THE GREAT LAKES LOOK RATHER
SIMILAR THROUGH THE PERIOD. WE USED A BLEND OF THE LONG RANGE
HPC/GMOS TEMPS AND GFS/ECMWF SKY COVER. POP CONTOURS WERE HAND
DRAWN BASED ON OVERLAID QPF FIELDS.
THE DAILIES...
THURSDAY... COLD FRONT MOVES OFFSHORE EARLY. UPPER TROUGH AND COLD
POOL MOVE ACROSS DURING THE DAY. SOME DESTABILIZATION/CAA ALOFT/
OVER OUR AREA...BUT THE FOCUS OF THIS WILL TAKE PLACE OVER
VT/NH/MAINE. EXPECT DIURNAL CUMULUS BUT AIRMASS LOOKS TOO DRY FOR
SHOWERS. MIXING WILL BE DEEP...REACHING ABOVE 800 MB. WINDS IN
THIS LAYER ARE EXPECTED TO REACH 35 KNOTS...EVEN A FEW INDICATIONS
OF NEAR 40 KNOTS HIGH IN THE LAYER. SO WIND GUSTS ABOVE 30 KNOTS
ARE ALSO EXPECTED DURING THE AFTERNOON. CLOUDS AND WIND DIMINISH
IN THE EVENING. TEMPS ARE A BLEND OF MOS.
FRIDAY THROUGH SUNDAY... DRY THROUGH THE PERIOD AS HIGH PRESSURE
BUILDS SOUTH FROM NORTHERN QUEBEC. THE HIGH SHIFTS OFFSHORE DURING
SUNDAY. THERE MAY BE ADDITIONAL DIURNAL CUMULUS ESPECIALLY ON FRIDAY-
SATURDAY AND IN THIS RESPECT THE FORECAST MAY BE TOO OPTIMISTIC WITH
SUNSHINE. BUT THE AIRMASS LOOKS SUFFICIENTLY DRY TO LIMIT CLOUD
DEVELOPMENT. TEMPS ARE A BLEND OF LONG-RANGE MOS.
SUNDAY NIGHT-MONDAY-TUESDAY... BUILDING RIDGE ALOFT WILL WORK TO
KEEP THE WEATHER DRY. WARM ADVECTION WEST OF THE SURFACE HIGH WILL
BRING ISENTROPIC LIFT AND WORK TO INCREASE SKY COVER. CLOUDS OVER
THE MID ATLANTIC/OHIO VALLEY WILL GET CAUGHT UP IN THE RETURN FLOW
AND GET DRAWN NORTH. NOT A LOT OF CONFIDENCE IN THIS PART OF THE
FORECAST...BUT MOST OF THE FAVORABLE PARAMETERS FOR SHOWERS WILL
REMAIN TO OUR WEST OVER NY/PA THIS PERIOD. SOME SEMBLANCE OF A
WARM FRONT MOVES THROUGH LATER SUNDAY NIGHT/MONDAY...AND WE HAVE
INCLUDED CHANCE POPS DURING THIS PERIOD IN OUR WESTERN AND
NORTHERN ZONES. MORE SHOWERS APPROACH FROM THE WEST LATE
TUESDAY...AND SO WE HAVE CHANCE POPS ENTER FROM THE WEST TUESDAY
NIGHT. STAY TUNED FOR LATER FORECAST CYCLES AS THIS SETUP BECOMES
CLEARER.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH WEDNESDAY NIGHT/...
TONIGHT...HIGH CONFIDENCE. VFR WITH DIMINISHING WIND. DIMINISHING
SKY COVER BETWEEN 9 PM AND MIDNIGHT.
WEDNESDAY...MODERATE TO HIGH CONFIDENCE. VFR MOST OF THE DAY. MAY
SEE PATCHY MVFR CIGS/VSBYS MOVE INTO CT VALLEY LATE IN THE DAY.
SCT SHOWERS MOVE IN FROM W-E DURING THE DAY AS WARM FRONT
APPROACHES.
WEDNESDAY NIGHT...MODERATE CONFIDENCE. CIGS/VSBYS LOWERING TO MVFR
WITH POCKETS OF IFR CONDITIONS IN SCT-WIDESPREAD SHOWERS AND FOG.
S-SW WINDS MAY GUST TO 25 KT EARLY BEFORE WIND SHIFT. LOW
CONFIDENCE OF ISOLD THUNDER. CONDITIONS IMPROVE ACROSS WESTERN
AREAS AFTER MIDNIGHT ON W-NW WINDS.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK...THURSDAY THROUGH SUNDAY...
THURSDAY... AREAS OF IFR IN MORNING FOG...OTHERWISE VFR. VFR
LEVEL CLOUDS DEVELOP MIDDAY/AFTERNOON ESPECIALLY SOUTHERN
NH/NORTHERN MASS. WEST-NORTHWEST WINDS INCREASE DURING THE
MORNING...WITH GUSTS TO 35 KNOTS EXPECTED IN THE AFTERNOON AND
DIMINISHING IN THE EVENING.
FRIDAY THROUGH SUNDAY... VFR THROUGH THE PERIOD. LIGHTER WINDS
WITH POTENTIAL FOR MIDDAY/AFTERNOON SEABREEZES EACH DAY.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH WEDNESDAY NIGHT/...
HIGH CONFIDENCE THROUGH PERIOD.
EXPECT WINDS AND SEAS TO REMAIN BELOW SMALL CRAFT THROUGH
WEDNESDAY MORNING. S-SW WINDS WILL PICK UP...GUSTING TO 25 KT OVER
THE OPEN WATERS. SEAS WILL ALSO BUILD...UP TO 8 FT ON THE OUTER
WATERS. WINDS WILL SHIFT TO W AND GRADUALLY DIMINISH LATE WED AS
COLD FRONT PASSES. SEAS WILL REMAIN AOA 5 FT THROUGH WED NIGHT.
OUTLOOK...THURSDAY THROUGH SUNDAY...
THURSDAY...SEAS 5 TO 7 FEET ON THE OUTER WATERS AND RI/BID
SOUNDS...SO A SMALL CRAFT ADVISORY FOR SEAS WILL CONTINUE TO BE
NEEDED. WINDS OVER LAND WILL INCREASE TO 25-35 KNOTS MIDDAY AND
AFTERNOON. SOME OF THIS WIND MAY AFFECT THE NEARSHORE WATERS AND
REQUIRE A SMALL CRAFT HEADLINE AS WELL.
FRIDAY THROUGH SUNDAY... WINDS AND SEAS EXPECTED TO REMAIN BELOW
SMALL CRAFT CRITERIA MOST OF THE PERIOD. SEAS ON THE OUTER WATERS
MAY APPROACH 5 FEET ON SUNDAY.
&&
.FIRE WEATHER...
WEDNESDAY...EXPECT MINIMUM RH VALUES TO RANGE FROM THE MID 30S
ACROSS E MA TO 50-60 PERCENT ACROSS S COAST...CAPE COD AND THE
ISLANDS EARLY WED...THEN WILL INCREASE AS CLOUDS AND SHOWERS MOVE
IN. GREEN-UP ALSO CONTINUES...AS MUCH OF THE REGION REMAINS BELOW
NORMAL FOR TOTAL RAINFALL OVER THE LAST TWO MONTHS. S-SW WINDS
WILL BECOME GUSTY...UP TO 20-25 KT WED AFTERNOON AND NIGHT BUT
SHOULD SEE WIDESPREAD SHOWERS MOVING IN. NOT EXPECTING A LOT OF
RAINFALL LATE WED AND WED NIGHT...MAINLY AROUND 0.25 INCHES.
THE FORECASTED RAINFALL WILL BE OF SOME HELP TOWARDS THE BELOW
NORMAL RAINFALL CONDITIONS. HOWEVER...THE REGION REMAINS DRY
POSSIBLY CONDUCIVE TOWARDS FUTURE FIRE WEATHER POTENTIAL.
OUTLOOK...
MINIMUM RELATIVE HUMIDITY FOR THURSDAY AND FRIDAY IS EXPECTED AT
20 TO 30 PERCENT EACH DAY. WEST-NORTHWEST WINDS ON THURSDAY WILL
INCREASE BY MIDDAY WITH AFTERNOON GUSTS TO 30 KNOTS AND POSSIBLY
35 KNOTS. THESE CONDITIONS ON THURSDAY WILL NEED TO BE WATCHED.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM WEDNESDAY TO 2 AM EDT THURSDAY
FOR ANZ232.
SMALL CRAFT ADVISORY FROM 2 PM WEDNESDAY TO 8 AM EDT THURSDAY
FOR ANZ235-237-250-254>256.
SMALL CRAFT ADVISORY FROM 2 PM WEDNESDAY TO 6 AM EDT THURSDAY
FOR ANZ251.
&&
$$
SYNOPSIS...WTB/EVT
NEAR TERM...WTB/EVT/THOMPSON
SHORT TERM...EVT
LONG TERM...WTB
AVIATION...WTB/EVT/THOMPSON
MARINE...WTB/EVT
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
540 PM EDT TUE MAY 14 2013
.SYNOPSIS...
HIGH PRESSURE WILL MOVE OFF THE SOUTHEAST COAST TONIGHT AND OUT TO
SEA INTO THURSDAY. A WARM FRONT IS FORECAST TO LIFT THROUGH OUR AREA
ON EARLY WEDNESDAY, FOLLOWED BY A COLD FRONT WEDNESDAY NIGHT. THIS
FRONT WILL SAG TO OUR SOUTH AND STALL FOR THE LATE WEEK PERIOD AND
INTO THE WEEKEND. THE FRONT MAY LIFT BACK NORTHWARD ACROSS THE AREA
AS A WARM FRONT EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
USED THE LATEST RAP AND HR3 TO MAKE SOME SOUTHWARD ADJUSTMENTS TO
MENTION OF PCPN AT ONSET EARLY OVERNIGHT. SO FAR AIRPORTS IN WRN
PA ARE OBSERVING TRACES. OTHERWISE TEMPS WERE TWEAKED SLIGHTLY
DOWNWARD BASED ON CURRENT TEMPS. MOST OTHER PARAMETERS AND GRIDS
DID NOT NEED MUCH CHANGE.
RAPIDLY THICKENING AND LOWERING CIGS ...THE BAND YOU SEE ON 19Z
SATELLITE IMAGERY FROM MICHIGAN TO W PTNS PA AND NYS. SCT LIGHT
SHOWERS EXPECTED...MOSTLY TRACE...AFTER MIDNIGHT AND MODELED IMO
PRETTY WELL BY THE 00Z/14 NSSL WRF AND NOW THE 18Z RAP...FLYING
SEWD 30-40 KT. LIGHT S WIND IN THE WAA PATTERN BEHIND THE
DEPARTING SFC HIGH OFF THE SE USA COAST.
50 50 BLENDED 12Z/14 NCEP MOS GUIDANCE FOR TEMPS/WINDS/DEWS.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
WEDNESDAY...THE 12Z GFS LOOKS LIKE MY IDEA OF A BEST MODEL SOLN OF
THE 12Z INTERNATIONAL SUITE. THE 12/14 GFS IMO HAS THE RIGHT IDEA
ABOUT STRONG CONVECTION AND PROBABLY STREAMING EAST SOUTHEAST FROM
SOUTHERN PA ACROSS S NJ AND OR THE DELMARVA LATE IN THE DAY WEDNESDAY.
SPC 1715Z SWODY2 ASSESSMENT MATCHES MY THINKING.
THE INCREASING BOUNDARY LAYER MOISTURE MAY BE OVERDONE BY THE MODELS,
THUS LIMITING INSTABILITY AND THE POTENTIAL FOR INITIATING CONVECTION.
THE 18Z GFS LAMP HAS GRIDDED LAMP TSTM PROBS IN W NYS AND NW PA BY
14Z.
MODEL REMNANTS OF AN EML NOW SPREADING EWD FROM THE MIDWEST THAT
SUPPORTS CONCERN FOR HAILERS....INCREASING THE 700-500MB LAPSE
RATES LATE IN THE DAY.
MORE THAN ADEQUATE BULK SHEAR FOR SVR WIND... AND SO THE QUESTION
BECOMES...IS THERE ENOUGH MOISTURE TO SUPPORT TSTM GENERATION. 12Z/14
GFS ML CAPE IS ONLY 600J LATER IN THE DAY AND SO DID NOT WORD HAIL
OR GUSTY WINDS IN THE ZONE PRODUCTS.
OTRW TEMPS/WINDS/DEWS ARE 50 50 BLENDED 12Z/14 NCEP MOS GUIDANCE
WITH A LEAN TO A WARMER TEMP SOLN SINCE MOST OF THE DAY SHOULD
BE RAINFREE.
CONFIDENCE ON POPS IS BELOW AVG AND I MAY BE OVER FCST THE CHC OF
A SHOWER OR TSTM WED AFTN.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
THE PRE-FRONTAL SURFACE TROUGH AND ANY ASSOCIATED CONVECTION SHOULD
BE PROGRESSING THROUGH THE AREA DURING THE EARLY EVENING TIME
WEDNESDAY. ONCE THE TROUGH MOVES THROUGH AND THE SUN GOES DOWN,
ANY CONVECTION SHOULD DIMINISH. THE ACTUAL COLD FRONT IS NOT
EXPECTED TO MOVE THROUGH THE AREA UNTIL WEDNESDAY NIGHT. THERE
STILL COULD BE A FEW SHOWERS AROUND UNTIL THE FRONT ACTUALLY MOVES
THROUGH, BUT ANY THUNDERSTORM ACTIVITY SHOULD HAVE ENDED BY THE
TIME THE FRONT APPROACHES.
THE AFOREMENTIONED COLD FRONT WILL SAG TO OUR SOUTH THURSDAY INTO
FRIDAY, WHILE THE PARENT LOW WILL SPIN THROUGH NEW ENGLAND AND
INTO THE CANADIAN MARITIMES. THIS WILL KEEP A STEADY WEST TO
NORTHWEST FLOW ACROSS THE AREA. EVEN THOUGH A WEAK SURFACE TROUGH
IS FORECAST TO CROSS THE AREA ON THURSDAY, MOST OF THE AREA SHOULD
REMAIN DRY THURSDAY AND FRIDAY. THE EXCEPTION TO THIS WILL BE
ACROSS THE SOUTHERN THIRD OF THE AREA, WHICH WOULD BE CLOSE TO THE
OLD COLD FRONT AS IT SLOWLY SAGS TO OUR SOUTH, BEFORE STALLING.
THERE MAY BE ENOUGH MOISTURE AND LIFT TO CREATE A FEW SCATTERED
SHOWERS/THUNDERSTORMS ACROSS SOUTHERN NEW JERSEY AND THE DELMARVA.
AS WE MOVE INTO THE WEEKEND, THE LOW TO OUR NORTHEAST WILL SLIDE OUT
TO SEA, ALLOWING FOR HIGH PRESSURE TO BUILD ACROSS THE NORTHEAST.
THIS HIGH IS EXPECTED TO PUSH OFF THE NEW ENGLAND COAST AND TO
OUR EAST THROUGH THE WEEKEND. THIS WILL PUT OUR AREA INTO AN
EASTERLY/SOUTHEASTERLY FLOW FOR MUCH OF THE WEEKEND, WHICH COULD
HELP KEEP OUR TEMPERATURES FRONT RISING VERY MUCH. IT MAY ALSO
KEEP SOME CLOUD COVER ACROSS THE AREA, AND WITH AN INCREASE IN
MOISTURE, ANY ADDITIONAL LIFT COULD LEAD TO SOME PRECIPITATION.
FOR NOW WE ONLY KEEP CHANCE/SLIGHT CHANCE POPS THROUGH THE
WEEKEND.
THE FRONT THAT STALLS TO OUR SOUTH IS EXPECTED TO BEGIN LIFTING
BACK NORTHWARD AS A WARM FRONT BY LATE SUNDAY INTO MONDAY. THIS
COULD LEAD TO SOME SHOWER ACTIVITY SUNDAY NIGHT INTO MONDAY. THEN
WE WAIT AND SEE WHAT HAPPENS WITH THE NEXT SYSTEM AS IT MOVES OUT
OF THE CENTRAL/NORTHERN PLAINS AND THROUGH THE GREAT LAKES.
GFS/ECMWF DIFFER ON HOW FAST THEY MOVE THE SYSTEM. IT`S POSSIBLE
IT COULD GET HERE AS EARLY AS WEDNESDAY, BUT WE WILL SEE HOW
MODELS HANDLE IT OVER THE NEXT FEW DAYS.
&&
.AVIATION /22Z TUESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
TONIGHT...VFR CIGS AOA 7000 FT DEVELOPING FM WNW TO ESE WITH SCT
SPRINKLES OR LIGHT .02/HR SHOWERS STREAMING SEWD 30-40 KT AFTER
04Z. LIGHT SOUTH SFC WIND.
WEDNESDAY...VFR SCT-BKN CLOUDS AOA 5000 FT WITH ONLY A SMALL
CHANCE OF A LEFTOVER SHOWER POSSIBLE IN THE MORNING BUT A BAND OF
SCT-BKN SHOWERS AND ISO STRONG TSTMS EXPECTED LATE IN THE DAY...
PROBABLY MOVING ESEWD THRU SE PA NEAR KPHL. SSW WIND GUSTS 15 KT
IN THE AFTN. STRONGER WLY GUST TO 35 KT `POSSIBLE` IN A LATE DAY
TSTM VCNTY KPHL. CONFIDENCE ON THUNDERSTORM INITIATION WED AFTN IN
SRN PA IS BELOW AVG DUE TO MOST MODELS NOT FCSTG MUCH IF ANY
SHOWER ACTIVITY.
OUTLOOK...
WEDNESDAY NIGHT...MOSTLY VFR CONDITIONS. MVFR POSSIBLE WITH ANY
SHOWERS/THUNDERSTORMS EARLY.
THURSDAY-FRIDAY...MOSTLY VFR CONDITIONS.
SATURDAY-SUNDAY...MAINLY VFR CONDITIONS...POSSIBLE PERIODS OF MVFR
SATURDAY NIGHT. SHOWERS ALSO POSSIBLE
&&
.MARINE...
HIGH PRESSURE WILL MOVE OVER THE SERN CONUS TODAY AND THEN FURTHER
EWD OVER THE SERN COASTAL WATERS TONIGHT. AS A RESULT THE WIND
AND SEAS ARE EXPECTED TO REMAIN BELOW SCA CRITERIA THRU THE NEAR
PERIOD.
WEDNESDAY...GUIDANCE INDICATES OUR COASTAL WATERS WILL REACH SCA
WIND GUSTS DURING THE DAYTIME WEDNESDAY WITH SEAS BUILDING TO 5
FT ON THE ATLC WATERS DURING THE AFTN GENERATED BY THE SLY FLOW
AHEAD OF AN APPROACHING WFRONT. FOR LOWER DE BAY THERE MAY BE A
PERIOD OF SCA WIND GUSTS WEDNESDAY BUT CONFIDENCE WAS NOT HIGH
ENOUGH AT THIS TIME TO INCLUDE THIS AS A HEADLINE.
AM STARTING THE SCA A BIT SOONER ON THE ATLC WATERS WEDNESDAY...
AROUND 12Z. WILL LEAVE IT TO THE MID SHIFT TO ISSUE FOR DE BAY.
OUTLOOK...
THE SMALL CRAFT ADVISORY WILL REMAIN IN EFFECT THROUGH WEDNESDAY
NIGHT AS SEAS WILL LIKELY REMAIN ABOVE 5 FEET AND WINDS COULD GUST
AROUND 25 KNOTS EARLY. HOWEVER, AFTER THE COLD FRONT MOVES
THROUGH, WINDS ARE EXPECTED TO DROP BELOW ADVISORY LEVELS THROUGH
FRIDAY NIGHT. SEAS MAY REMAIN AROUND 5 FEET INTO EARLY THURSDAY,
BUT NOT CONFIDENT ENOUGH TO EXTEND THE ADVISORY OUT ANOTHER DAY
YET. ONCE SEAS DROP BELOW 5 FEET, THEY WILL REMAIN SO THROUGH
FRIDAY NIGHT.
AS WE MOVE INTO THE WEEKEND, HIGH PRESSURE BUILDS TO OUR
NORTH/NORTHEAST, WHICH WILL PRESENT AN EAST/SOUTHEAST FETCH ACROSS
THE WATERS. WINDS COULD BEGIN APPROACHING SMALL CRAFT CONDITIONS
STARTING SATURDAY NIGHT AND SEAS COULD BEGIN INCREASING AS WELL
CLOSE TO 5 FEET BY SUNDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 7 AM WEDNESDAY TO 8 AM EDT THURSDAY
FOR ANZ450>455.
&&
$$
SYNOPSIS...ROBERTSON
NEAR TERM...DRAG/GIGI
SHORT TERM...DRAG
LONG TERM...ROBERTSON
AVIATION...DRAG/ROBERTSON
MARINE...DRAG/ROBERTSON
AREA FORECAST DISCUSSION
NWS LINCOLN IL
837 PM CDT WED MAY 15 2013
.DISCUSSION...
ISSUED 837 PM CDT WED MAY 15 2013
STATIONARY FRONTAL BOUNDARY BISECTS CENTRAL ILLINOIS THIS
EVENING...WITH COOLER/SLIGHTLY DRIER AIR FILTERING INTO THE FAR
NORTHERN KILX CWA WHERE DEWPOINTS HAVE DROPPED INTO THE UPPER 40S
AND LOWER 50S. FURTHER SOUTH...MOISTURE POOLING ALONG THE BOUNDARY
HAS RESULTED IN DEWPOINTS IN THE LOWER 60S ALONG THE I-72
CORRIDOR. 01Z/8PM IR SATELLITE IMAGERY IS BEGINNING TO SHOW AC
DEVELOPING ALONG THE FRONT...WITH REGIONAL RADAR SHOWING SCATTERED
THUNDERSTORMS DEVELOPING FURTHER WEST ACROSS NORTHERN MISSOURI.
23Z HRRR SUGGESTS CONVECTION WILL DEVELOP EASTWARD ALONG THE
FRONT INTO WEST-CENTRAL ILLINOIS AFTER 03Z/10PM. BASED ON POSITION
OF FRONT AND LATEST HIGH-RES MODEL DATA...HAVE LOWERED POPS TO
JUST SLIGHT CHANCE ACROSS THE SE CWA ALONG/SOUTH OF I-70. FURTHER
NORTH...WENT WITH SCATTERED WORDING ACROSS THE CENTRAL AND
NORTHERN ZONES IN CLOSER PROXIMITY TO THE BOUNDARY. ALSO ADJUSTED
OVERNIGHT LOWS UP A FEW DEGREES...WITH LOWER TO MIDDLE 60S IN MOST
LOCATIONS...EXCEPT COOLER UPPER 50S FAR NORTH. ZONE UPDATE HAS
ALREADY BEEN ISSUED.
BARNES
&&
.AVIATION...
ISSUED 632 PM CDT WED MAY 15 2013
STATIONARY FRONTAL BOUNDARY CURRENTLY DRAPED ACROSS THE AREA WILL
BE THE MAIN FOCUSING MECHANISM FOR WIDELY SCATTERED SHOWERS/THUNDER
THROUGH THE ENTIRE 00Z TAF PERIOD. LATEST RADAR IMAGERY SHOWS VERY
LITTLE PRECIP OCCURRING NOW...ALTHOUGH MOST HIGH-RES MODELS TEND
TO DEVELOP CONVECTION ALONG THE I-72 CORRIDOR AFTER 03Z. WHILE
SOME MODEL SOLUTIONS DIMINISH THIS SCATTERED CONVECTION
OVERNIGHT...OTHERS KEEP IT GOING RIGHT THROUGH THE NIGHT INTO
THURSDAY. DUE TO UNCERTAINTIES CONCERNING EXACT TIMING AND
LOCATION OF ANY CONVECTION...HAVE OPTED TO CARRY ONLY VCTS AT THE
TAF SITES FOR THIS FORECAST ISSUANCE. WILL MENTION THUNDER BETWEEN
03Z AND 08Z AT THE I-72 TERMINALS...WITH DRY CONDITIONS FURTHER
NORTH. AFTER THAT...WILL BRING BACK VCTS AFTER 14Z AS DAYTIME
INSTABILITY RETURNS AND SCATTERED SHOWERS/STORMS DEVELOP IN THE
VICINITY OF THE BOUNDARY. WILL KEEP THUNDER OUT OF THE TAF FOR
BOTH KPIA AND KBMI UNTIL THURSDAY AFTERNOON ONCE FRONT SLOWLY
BEGINS TO RETREAT BACK NORTHWARD. WINDS WILL BE LIGHT/VARIABLE
THROUGHOUT THE PERIOD.
BARNES
&&
.PREV DISCUSSION...
ISSUED 259 PM CDT WED MAY 15 2013
FORECAST CONCERN TODAY IS THE POPS ASSOCIATED WITH THE STALLING
FRONT OVER THE REGION INTO THE WEEKEND...AND THEN THE APPROACH OF
THE MAIN UPPER WAVE AND FRONT THE FIRST PART OF NEXT WEEK.
.SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT.
MORNING UPPER AIR DATA AND SPC INSTABILITY ANALYSIS SHOWS THE
EAST-WEST FRONTAL ZONE HAD MADE INTO THE NORTH CENTRAL PART OF IL
TODAY...WITH ENOUGH CONVERGENCE ON THE BOUNDARY TO CONTINUE THE
TREND THAT BEGAN OVERNIGHT...OF ELEVATED CONVECTION FORMING AND
MOVING EAST ALONG THE FRONTAL ZONE. THIS TREND HAS BEEN THE CASE
ALL DAY...AS THE UPPER AIR SHOWED A TONGUE OF LOW LEVEL MOISTURE
SURGING NORTH FROM TX OVER MO INTO THE BOUNDARY ZONE. SPC MESODATA
CONTINUED TO SHOW AIR SOUTH OF THE BOUNDARY CAPPED AND THE PCPN
REMAINING ELEVATED. EXPECT THIS TREND TO REMAIN OVERNIGHT...WITH
THE FRONT SAGGING A LITTLE SOUTH.
WITH THE FRONT PROGGED TO BE IN THE REGION BY ALL THE MODELS ON
THURSDAY...WILL KEEP POPS IN THE LIKELY CAT THROUGH CENTRAL REGION.
ADDITIONAL SUPPORT FOR DEVELOPMENT WITH UPPER LEVEL REMAINS OF THE
WEAKENING UPPER WAVE THAT IS OVER TX TODAY. THAT SYSTEM WILL BE
DRIFTING TO THE EAST NORTHEAST OVER OK TO AR. THIS SYSTEM IS
FORECAST TO WASH OUT THURSDAY NIGHT AND THEN THE UPPER RIDGE
BEGINS TO START TO BUILD OVER AREA. LOWERING POPS THEN FRIDAY AND
INTO FRIDAY NIGHT.
.LONG TERM...SATURDAY THROUGH WEDNESDAY.
THE APPROACH OF THE DEEPENING UPPER LOW/WAVE ON SUNDAY GRADUALLY
INCREASES POPS OVER WEST SUNDAY. GFS AND NEW EUR ARE DIFFERENT IN
THE DETAILS ON THE APPROACHING FRONT AND THE UPPER LOW/TROUGH
CONFIGURATION. TODAYS RUN DOES NOT DISPLAY A CLEAR SYSTEM MOVING
THROUGH...BUT A MORE GRADUAL MOVEMENT OF THE UPPER SYSTEM...WHICH
RESULTS IN A LONGER PERIOD OF POPS...FOR SUNDAY INTO THE DAY
WEDNESDAY. WILL STILL HAVE TO WATCH MONDAY FOR SIGNIFICANT
CONVECTION...AS SOUNDING AND HODOGRAPH ON THAT DAY STILL SHOW
POTENTIAL FOR STRONG STORMS.
GOETSCH
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1233 PM CDT TUE MAY 14 2013
...UPDATED AVIATION AND PUBLIC DISCUSSION...
.UPDATE...
ISSUED AT 1233 PM CDT TUE MAY 14 2013
HOT CONDITIONS CONTINUE TO STREAM INTO WESTERN AND NORTHWEST IOWA...
ALREADY BREAKING RECORDS IN SOME PORTIONS OF THE STATE TODAY. WINDS
GENERALLY FULLY MIXED NOW SO WARMING OVER THESE AREAS WILL SLOW...
BUT STILL MANAGE TO PUSH A FEW SPOTS IN OUR WEST TO NORTHWEST
FORECAST AREA IN EXCESS OF 100F THIS AFTERNOON. HIGHS ACROSS CENTRAL
AND SOUTHEAST LOOK REASONABLE...AND HAVE RAISED HIGHS NORTH AND WEST
PORTIONS FOR TODAY. DEW POINTS HAVE RISEN MOST AREAS THROUGH THE
MORNING HOURS AND HAVE MADE ADJUSTMENTS...SOME POOLING TAKING PLACE
OVER CENTRAL IOWA NOW...WITH AREAS SEEING MIXING DEW POINTS RAPIDLY
TANKING BACK INTO THE 40S.
.SHORT TERM.../TODAY/...
ISSUED AT 407 AM CDT TUE MAY 14 2013
FORECAST CHALLENGE TODAY IS WITH RECORD OR
NEAR RECORD HIGH MAX TEMPS...DEW POINTS AND WINDS. MODELS STILL
INITIALIZING TOO MOIST WITH THE RAP CONTINUING TO BE THE DRY
SOLUTION TODAY. RAP ALSO HAS THE BETTER HANDLE ON THE TEMPS
TODAY...SO LEANED CLOSER TO THE RAP SOLUTION.
WINDS WILL INCREASE LATE THIS MORNING AND CONTINUE TO MIX DURING THE
AFTERNOON WITH RAP SHOWING THE BEST DRY ADIABATIC SOUNDING. MIXING
TO 850MB SHOULD TAP INTO THE +25C TEMPERATURES ADVECTING INTO
WESTERN TO NORTHERN IOWA BY THIS AFTERNOON. NAM/GFS/ECMWF SOUNDINGS
ARE NOT AS AGGRESSIVE WITH THE MIXING TODAY...AND POSSIBLY ONE
REASON THESE MODELS OVERDOING THE DEW POINTS. TEMPS OVERNIGHT
REMAINING IN THE UPPER 50S/LOWER 60S ACROSS MUCH OF THE FORECAST
AREA...AND WITH THE NORTHWEST FORECAST AREA RISING 2-4 DEGREES
WARMER MONDAY THAN ANTICIPATED...CONFIDENT ENOUGH TO TWEAK MAX TEMPS
UP SLIGHTLY OVER THE WEST AND NORTH. WENT ROUGHLY 3 TO 5 DEGREES
ABOVE THE WARMEST GUIDANCE TODAY. WITH THE DRIER DEW POINTS AND RH
VALUES COMBINED WITH THE GUSTY SOUTHWEST WINDS...DECIDED TO UPGRADE
TO A RED FLAG WARNING. SEE FIRE WEATHER DISCUSSION FOR FURTHER
DETAILS.
.LONG TERM.../TONIGHT THROUGH MONDAY/...
ISSUED AT 400 AM CDT TUE MAY 14 2013
THE FRONTAL BOUNDARY WILL DROP SLOWLY SOUTH THROUGH THE STATE
OVERNIGHT BEFORE STALLING IN THE ZONAL FLOW JUST SOUTH INTO
MISSOURI ON WEDNESDAY. MOISTURE REMAINS QUITE LIMITED WITH THE
SYSTEM. ANY SHOWERS AND THUNDERSTORMS THAT DO FORM WILL BE
EXTREMELY HIGH BASED AND ABOVE THE PRIMARY AREA OF FORCING. THIS
COMBINED WITH THE LACK OF ASSOCIATED MOISTURE WILL KEEP ANY
ACTIVITY QUITE SPARSE. BROAD AREA OF LOW PRESSURE WILL BECOME
REFOCUSED OVER WYOMING AND THE WESTERN DAKOTAS THURSDAY INTO
FRIDAY. THIS WILL HELP DRIVE THE FRONTAL BOUNDARY BACK NORTH AS A
WARM FRONT. PRECIPITATION CHANCES WILL CONTINUE MAINLY OVER THE
SOUTH WEDNESDAY BEFORE SPREADING BACK NORTH WITH THE FRONTAL
PASSAGE THROUGH THE END OF THE WEEK.
HAVE MAINTAINED THUNDERSTORM CHANCES ON SATURDAY THOUGH THE SIGNS
BEGINNING TO POINT TO THE STATE BEING IN THE WARM SECTOR WITH THE
WARM FRONT MOVING NORTH OF THE STATE. WARM AIR ALOFT WOULD LEAVE A
FAIR AMOUNT OF CONVECTIVE INHIBITION TO OVERCOME ON SATURDAY.
BETTER CHANCE FOR THUNDERSTORMS AND POSSIBLY SEVERE WEATHER WOULD
BE SUNDAY AS A THE UPPER LEVEL RIDGE BEGINS TO BE SHOVED EAST BY
AN UPPER LEVEL SYSTEM ENTERING THE NORTHWESTERN CONUS. THIS WILL
INCREASE THE SOUTHWEST FLOW INTO THE STATE EARLY SUNDAY WITH A
COLD FRONT ARRIVING LATER IN THE DAY. CERTAINLY A FAVORABLE SETUP
FOR SURFACE BASED CONVECTION WITH THE PRIMARY THREATS OF WIND AND
HAIL WITH THE TRIPLE POINT WELL TO THE NORTH...BUT IT IS STILL
SEVERAL DAYS AWAY.
TEMPERATURES THROUGH THE PERIOD WILL BE SEASONAL TO ABOVE NORMAL.
POSSIBLY CLOUD COVER ON WEDNESDAY AND THURSDAY WILL HAVE AN IMPACT
ON TEMPERATURES. THURSDAY ESPECIALLY WILL BE COOLER THAN THE NORTH
DUE TO PRECIPITATION AND CLOUDS. LIKELY A RETURN TO THE 80S ON
SATURDAY WITH DEWPOINTS POSSIBLY RISING INTO THE 60S.
&&
.AVIATION...14/18Z
ISSUED AT 1233 PM CDT TUE MAY 14 2013
MAIN CONCERNS THIS PERIOD REMAIN WINDS AND POTENTIAL FOR SOME
THUNDER FOR THE LATE AFTERNOON AND OVERNIGHT HOURS. WINDS CONTINUE
STRONG NORTHWEST AND NORTH AREAS WHERE MIXED LAYER RAPIDLY REACHING
FULL DEPTH EARLY THIS AFTERNOON. WILL CONTINUE TO SEE STRONG WINDS
THROUGH 23Z DIMINISHING THEREAFTER. WITH MOISTURE POOLING OVER
PORTIONS OF CENTRAL IOWA...SOME CONCERNS OF INSTABILITY THOUGH NO
FOCUSING MECHANISM UNTIL BOUNDARY APPROACHES THIS EVENING. WITH
BOUNDARY SOUTH OF AREA OVERNIGHT...SOME RETURN FLOW ALOFT SHOWS MORE
PROMISE TO INITIATE SCATTERED CONVECTION OVER THE SOUTH. HAVE
INCLUDED VCSH FOR KDSM AND KOTM...BUT OTHERWISE WILL KEEP DRY FOR
THIS PERIOD UNTIL ANY BETTER ORGANIZATION SHOWS ITS HAND.
&&
.FIRE WEATHER...
UPDATE AT 1233 PM TUE...NO CHANGES TO GOING CONDITIONS AND AREAL
EXTENT FOR THE REMAINDER OF THIS AFTERNOON.
STRONGEST WIND GUSTS AND LOWEST RELATIVE HUMIDITY VALUES ARE
EXPECTED BETWEEN NOON AND 7PM TODAY OVER WESTERN AND NORTHERN
PORTIONS OF THE FORECAST AREA. RH VALUES RANGING FROM 17 TO 22
PERCENT AND SUSTAINED WINDS AROUND 25 MPH OR SLIGHTLY HIGHER ARE
LIKELY DURING THE AFTERNOON. GFDI VALUES RANGES IN THE MODERATE TO
HIGH CATEGORY PAST NOON TODAY AND MAY BARELY BUMP INTO THE EXTREME
CATEGORY FOR A FEW HOURS BETWEEN 2PM AND 5PM THIS AFTERNOON.
MIXING HEIGHT LOOKS TO BE IN THE 3000 TO 3500 FEET LATE THIS
MORNING AND INTO THE AFTERNOON...WITH A SHORT STINT OF MIXING
HIGHER. REPLACED THE FIRE WEATHER WATCH WITH A RED FLAG WARNING
DUE TO THE VERY LOW RH VALUES...STRONG WINDS...AND FUELS NOT
ENTIRELY GREEN YET.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR
ADAIR-ADAMS-AUDUBON-BOONE-CALHOUN-CARROLL-CASS-CERRO GORDO-
CRAWFORD-DALLAS-EMMET-FRANKLIN-GREENE-GUTHRIE-HAMILTON-HANCOCK-
HUMBOLDT-KOSSUTH-PALO ALTO-POCAHONTAS-SAC-WEBSTER-WINNEBAGO-
WORTH-WRIGHT.
&&
$$
SHORT TERM...PODRAZIK
LONG TERM...DONAVON
AVIATION...REV
FIRE WEATHER...PODRAZIK
AREA FORECAST DISCUSSION
NWS DES MOINES IA
643 AM CDT TUE MAY 14 2013
...UPDATED AVIATION DISCUSSION...
.SHORT TERM.../TODAY /...
ISSUED AT 407 AM CDT TUE MAY 14 2013
FORECAST CHALLENGE TODAY IS WITH RECORD OR
NEAR RECORD HIGH MAX TEMPS...DEW POINTS AND WINDS. MODELS STILL
INITIALIZING TOO MOIST WITH THE RAP CONTINUING TO BE THE DRY
SOLUTION TODAY. RAP ALSO HAS THE BETTER HANDLE ON THE TEMPS
TODAY...SO LEANED CLOSER TO THE RAP SOLUTION.
WINDS WILL INCREASE LATE THIS MORNING AND CONTINUE TO MIX DURING THE
AFTERNOON WITH RAP SHOWING THE BEST DRY ADIABATIC SOUNDING. MIXING
TO 850MB SHOULD TAP INTO THE +25C TEMPERATURES ADVECTING INTO
WESTERN TO NORTHERN IOWA BY THIS AFTERNOON. NAM/GFS/ECMWF SOUNDINGS
ARE NOT AS AGGRESSIVE WITH THE MIXING TODAY...AND POSSIBLY ONE
REASON THESE MODELS OVERDOING THE DEW POINTS. TEMPS OVERNIGHT
REMAINING IN THE UPPER 50S/LOWER 60S ACROSS MUCH OF THE FORECAST
AREA...AND WITH THE NORTHWEST FORECAST AREA RISING 2-4 DEGREES
WARMER MONDAY THAN ANTICIPATED...CONFIDENT ENOUGH TO TWEAK MAX TEMPS
UP SLIGHTLY OVER THE WEST AND NORTH. WENT ROUGHLY 3 TO 5 DEGREES
ABOVE THE WARMEST GUIDANCE TODAY. WITH THE DRIER DEW POINTS AND RH
VALUES COMBINED WITH THE GUSTY SOUTHWEST WINDS...DECIDED TO UPGRADE
TO A RED FLAG WARNING. SEE FIRE WEATHER DISCUSSION FOR FURTHER
DETAILS.
.LONG TERM.../TONIGHT THROUGH MONDAY/...
ISSUED AT 400 AM CDT TUE MAY 14 2013
THE FRONTAL BOUNDARY WILL DROP SLOWLY SOUTH THROUGH THE STATE
OVERNIGHT BEFORE STALLING IN THE ZONAL FLOW JUST SOUTH INTO
MISSOURI ON WEDNESDAY. MOISTURE REMAINS QUITE LIMITED WITH THE
SYSTEM. ANY SHOWERS AND THUNDERSTORMS THAT DO FORM WILL BE
EXTREMELY HIGH BASED AND ABOVE THE PRIMARY AREA OF FORCING. THIS
COMBINED WITH THE LACK OF ASSOCIATED MOISTURE WILL KEEP ANY
ACTIVITY QUITE SPARSE. BROAD AREA OF LOW PRESSURE WILL BECOME
REFOCUSED OVER WYOMING AND THE WESTERN DAKOTAS THURSDAY INTO
FRIDAY. THIS WILL HELP DRIVE THE FRONTAL BOUNDARY BACK NORTH AS A
WARM FRONT. PRECIPITATION CHANCES WILL CONTINUE MAINLY OVER THE
SOUTH WEDNESDAY BEFORE SPREADING BACK NORTH WITH THE FRONTAL
PASSAGE THROUGH THE END OF THE WEEK.
HAVE MAINTAINED THUNDERSTORM CHANCES ON SATURDAY THOUGH THE SIGNS
BEGINNING TO POINT TO THE STATE BEING IN THE WARM SECTOR WITH THE
WARM FRONT MOVING NORTH OF THE STATE. WARM AIR ALOFT WOULD LEAVE A
FAIR AMOUNT OF CONVECTIVE INHIBITION TO OVERCOME ON SATURDAY.
BETTER CHANCE FOR THUNDERSTORMS AND POSSIBLY SEVERE WEATHER WOULD
BE SUNDAY AS A THE UPPER LEVEL RIDGE BEGINS TO BE SHOVED EAST BY
AN UPPER LEVEL SYSTEM ENTERING THE NORTHWESTERN CONUS. THIS WILL
INCREASE THE SOUTHWEST FLOW INTO THE STATE EARLY SUNDAY WITH A
COLD FRONT ARRIVING LATER IN THE DAY. CERTAINLY A FAVORABLE SETUP
FOR SURFACE BASED CONVECTION WITH THE PRIMARY THREATS OF WIND AND
HAIL WITH THE TRIPLE POINT WELL TO THE NORTH...BUT IT IS STILL
SEVERAL DAYS AWAY.
TEMPERATURES THROUGH THE PERIOD WILL BE SEASONAL TO ABOVE NORMAL.
POSSIBLY CLOUD COVER ON WEDNESDAY AND THURSDAY WILL HAVE AN IMPACT
ON TEMPERATURES. THURSDAY ESPECIALLY WILL BE COOLER THAN THE NORTH
DUE TO PRECIPITATION AND CLOUDS. LIKELY A RETURN TO THE 80S ON
SATURDAY WITH DEWPOINTS POSSIBLY RISING INTO THE 60S.
&&
.AVIATION...14/12Z
ISSUED AT 641 AM CDT TUE MAY 14 2013
WINDS WILL INCREASE LATE THIS MORNING AND EXPECTING STRONGEST
WINDS TO MIX DURING THE AFTERNOON. SHOULD SEE SOME GUSTS AT
MCW/DSM/FOD TO AROUND 30 KNOTS...SLIGHTLY LESS AT ALO/OTM.
OTHERWISE...VFR CONDITIONS WILL PREVAIL.
&&
.FIRE WEATHER...
STRONGEST WIND GUSTS AND LOWEST RELATIVE HUMIDITY VALUES ARE
EXPECTED BETWEEN NOON AND 7PM TODAY OVER WESTERN AND NORTHERN
PORTIONS OF THE FORECAST AREA. RH VALUES RANGING FROM 17 TO 22
PERCENT AND SUSTAINED WINDS AROUND 25 MPH OR SLIGHTLY HIGHER ARE
LIKELY DURING THE AFTERNOON. GFDI VALUES RANGES IN THE MODERATE TO
HIGH CATEGORY PAST NOON TODAY AND MAY BARELY BUMP INTO THE EXTREME
CATEGORY FOR A FEW HOURS BETWEEN 2PM AND 5PM THIS AFTERNOON.
MIXING HEIGHT LOOKS TO BE IN THE 3000 TO 3500 FEET LATE THIS
MORNING AND INTO THE AFTERNOON...WITH A SHORT STINT OF MIXING
HIGHER. REPLACED THE FIRE WEATHER WATCH WITH A RED FLAG WARNING
DUE TO THE VERY LOW RH VALUES...STRONG WINDS...AND FUELS NOT
ENTIRELY GREEN YET.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR
ADAIR-ADAMS-AUDUBON-BOONE-CALHOUN-CARROLL-CASS-CERRO GORDO-
CRAWFORD-DALLAS-EMMET-FRANKLIN-GREENE-GUTHRIE-HAMILTON-HANCOCK-
HUMBOLDT-KOSSUTH-PALO ALTO-POCAHONTAS-SAC-WEBSTER-WINNEBAGO-
WORTH-WRIGHT.
&&
$$
SHORT TERM...PODRAZIK
LONG TERM...DONAVON
AVIATION...PODRAZIK
FIRE WEATHER...PODRAZIK
AREA FORECAST DISCUSSION
NWS DES MOINES IA
408 AM CDT TUE MAY 14 2013
.SHORT TERM.../TODAY /...
ISSUED AT 407 AM CDT TUE MAY 14 2013
FORECAST CHALLENGE TODAY IS WITH RECORD OR
NEAR RECORD HIGH MAX TEMPS...DEW POINTS AND WINDS. MODELS STILL
INITIALIZING TOO MOIST WITH THE RAP CONTINUING TO BE THE DRY
SOLUTION TODAY. RAP ALSO HAS THE BETTER HANDLE ON THE TEMPS
TODAY...SO LEANED CLOSER TO THE RAP SOLUTION.
WINDS WILL INCREASE LATE THIS MORNING AND CONTINUE TO MIX DURING THE
AFTERNOON WITH RAP SHOWING THE BEST DRY ADIABATIC SOUNDING. MIXING
TO 850MB SHOULD TAP INTO THE +25C TEMPERATURES ADVECTING INTO
WESTERN TO NORTHERN IOWA BY THIS AFTERNOON. NAM/GFS/ECMWF SOUNDINGS
ARE NOT AS AGGRESSIVE WITH THE MIXING TODAY...AND POSSIBLY ONE
REASON THESE MODELS OVERDOING THE DEW POINTS. TEMPS OVERNIGHT
REMAINING IN THE UPPER 50S/LOWER 60S ACROSS MUCH OF THE FORECAST
AREA...AND WITH THE NORTHWEST FORECAST AREA RISING 2-4 DEGREES
WARMER MONDAY THAN ANTICIPATED...CONFIDENT ENOUGH TO TWEAK MAX TEMPS
UP SLIGHTLY OVER THE WEST AND NORTH. WENT ROUGHLY 3 TO 5 DEGREES
ABOVE THE WARMEST GUIDANCE TODAY. WITH THE DRIER DEW POINTS AND RH
VALUES COMBINED WITH THE GUSTY SOUTHWEST WINDS...DECIDED TO UPGRADE
TO A RED FLAG WARNING. SEE FIRE WEATHER DISCUSSION FOR FURTHER
DETAILS.
.LONG TERM.../TONIGHT THROUGH MONDAY/...
ISSUED AT 400 AM CDT TUE MAY 14 2013
THE FRONTAL BOUNDARY WILL DROP SLOWLY SOUTH THROUGH THE STATE
OVERNIGHT BEFORE STALLING IN THE ZONAL FLOW JUST SOUTH INTO
MISSOURI ON WEDNESDAY. MOISTURE REMAINS QUITE LIMITED WITH THE
SYSTEM. ANY SHOWERS AND THUNDERSTORMS THAT DO FORM WILL BE
EXTREMELY HIGH BASED AND ABOVE THE PRIMARY AREA OF FORCING. THIS
COMBINED WITH THE LACK OF ASSOCIATED MOISTURE WILL KEEP ANY
ACTIVITY QUITE SPARSE. BROAD AREA OF LOW PRESSURE WILL BECOME
REFOCUSED OVER WYOMING AND THE WESTERN DAKOTAS THURSDAY INTO
FRIDAY. THIS WILL HELP DRIVE THE FRONTAL BOUNDARY BACK NORTH AS A
WARM FRONT. PRECIPITATION CHANCES WILL CONTINUE MAINLY OVER THE
SOUTH WEDNESDAY BEFORE SPREADING BACK NORTH WITH THE FRONTAL
PASSAGE THROUGH THE END OF THE WEEK.
HAVE MAINTAINED THUNDERSTORM CHANCES ON SATURDAY THOUGH THE SIGNS
BEGINNING TO POINT TO THE STATE BEING IN THE WARM SECTOR WITH THE
WARM FRONT MOVING NORTH OF THE STATE. WARM AIR ALOFT WOULD LEAVE A
FAIR AMOUNT OF CONVECTIVE INHIBITION TO OVERCOME ON SATURDAY.
BETTER CHANCE FOR THUNDERSTORMS AND POSSIBLY SEVERE WEATHER WOULD
BE SUNDAY AS A THE UPPER LEVEL RIDGE BEGINS TO BE SHOVED EAST BY
AN UPPER LEVEL SYSTEM ENTERING THE NORTHWESTERN CONUS. THIS WILL
INCREASE THE SOUTHWEST FLOW INTO THE STATE EARLY SUNDAY WITH A
COLD FRONT ARRIVING LATER IN THE DAY. CERTAINLY A FAVORABLE SETUP
FOR SURFACE BASED CONVECTION WITH THE PRIMARY THREATS OF WIND AND
HAIL WITH THE TRIPLE POINT WELL TO THE NORTH...BUT IT IS STILL
SEVERAL DAYS AWAY.
TEMPERATURES THROUGH THE PERIOD WILL BE SEASONAL TO ABOVE NORMAL.
POSSIBLY CLOUD COVER ON WEDNESDAY AND THURSDAY WILL HAVE AN IMPACT
ON TEMPERATURES. THURSDAY ESPECIALLY WILL BE COOLER THAN THE NORTH
DUE TO PRECIPITATION AND CLOUDS. LIKELY A RETURN TO THE 80S ON
SATURDAY WITH DEWPOINTS POSSIBLY RISING INTO THE 60S.
&&
.AVIATION...14/06Z
ISSUED AT 1145 PM CDT MON MAY 13 2013
VFR CONDITIONS THROUGH THE TAF PERIOD...WITH SOUTHERLY WINDS
INCREASING THROUGH THE DAY TUESDAY. WINDS TO BECOME MORE
SOUTHWESTERLY TO WESTERLY AS A FRONTAL BOUNDARY APPROACHES TUESDAY
EVENING. SCT-BKN150 HIGH CLOUDS POSSIBLE THROUGH THE PERIOD.
&&
.FIRE WEATHER...
STRONGEST WIND GUSTS AND LOWEST RELATIVE HUMIDITY VALUES ARE
EXPECTED BETWEEN NOON AND 7PM TODAY OVER WESTERN AND NORTHERN
PORTIONS OF THE FORECAST AREA. RH VALUES RANGING FROM 17 TO 22
PERCENT AND SUSTAINED WINDS AROUND 25 MPH OR SLIGHTLY HIGHER ARE
LIKELY DURING THE AFTERNOON. GFDI VALUES RANGES IN THE MODERATE TO
HIGH CATEGORY PAST NOON TODAY AND MAY BARELY BUMP INTO THE EXTREME
CATEGORY FOR A FEW HOURS BETWEEN 2PM AND 5PM THIS AFTERNOON.
MIXING HEIGHT LOOKS TO BE IN THE 3000 TO 3500 FEET LATE THIS
MORNING AND INTO THE AFTERNOON...WITH A SHORT STINT OF MIXING
HIGHER. REPLACED THE FIRE WEATHER WATCH WITH A RED FLAG WARNING
DUE TO THE VERY LOW RH VALUES...STRONG WINDS...AND FUELS NOT
ENTIRELY GREEN YET.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR
ADAIR-ADAMS-AUDUBON-BOONE-CALHOUN-CARROLL-CASS-CERRO GORDO-
CRAWFORD-DALLAS-EMMET-FRANKLIN-GREENE-GUTHRIE-HAMILTON-HANCOCK-
HUMBOLDT-KOSSUTH-PALO ALTO-POCAHONTAS-SAC-WEBSTER-WINNEBAGO-
WORTH-WRIGHT.
&&
$$
SHORT TERM...PODRAZIK
LONG TERM...DONAVON
AVIATION...BEERENDS
FIRE WEATHER...PODRAZIK
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
355 PM CDT TUE MAY 14 2013
...UPDATED LONG TERM SECTION...
.SYNOPSIS...
ISSUED AT 931 AM CDT TUE MAY 14 2013
THE 14.12Z 250 HPA RAOB MAP SHOWED TWO JETS ACROSS NORTH AMERICA. THE
POLAR JET WAS LOCATED ACROSS THE NORTHERN PORTIONS OF UNITED STATES
AND INTO CANADA. THE STRONGEST WINDS WERE LOCATED FROM NOVA SCOTIA AND
INTO THE CANADIAN MARITIMES WITH MAGNITUDES AROUND 180 KT. NEXT, THE
SUBTROPICAL JET WAS LOCATED FARTHER SOUTH WITH HIGHEST MAGNITUDES AROUND
90 KT ACROSS FLORIDA. CLOSER TO KANSAS, FLOW WAS QUITE WEAK AT 15 KT. AT
500 HPA, A TROF WAS MOVING ONSHORE ACROSS CENTRAL CALIFORNIA. DAMPENING
SHORTWAVE RIDGING WAS DOWNSTREAM OF THIS FEATURE ACROSS THE 4 CORNERS
REGION. A WEAK LOW WAS LOCATED ACROSS PORTIONS OF MEXICO. A SHORTWAVE
TROF WAS MOVING ACROSS THE CENTRAL CANADIAN PRAIRIES. AN ELONGATED TROF
WAS LOCATED ACROSS THE NE U.S. AND SE CANADA. AT 700 HPA, TEMPERATURES
ACROSS SW KANSAS WERE FAIRLY WARM (10 DEG C). AT 850 HPA, 25 DEG C AT
KDDC WAS SLIGHTLY UNDER THE +2 STANDARD DEVIATION STATISTICAL MARK.
AT THE SFC, A COLD FRONT WAS LOCATED ACROSS THE NORTHERN PLAINS AND
A SURFACE LEE TROF WAS LOCATED ACROSS FAR WESTERN KANSAS.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 252 PM CDT TUE MAY 14 2013
TONIGHT:
EARLY AFTERNOON VISIBLE SATELLITE IMAGERY SHOWS A FIELD OF CUMULUS HUMILIS
CLOUDS ACROSS NORTHWEST KANSAS. THESE CLOUDS ARE IN ASSOCIATION WITH
A LEE SURFACE TROF ACROSS NORTHWEST KANSAS AND WEAK INSTABILITY. RAP
AND HRRR KEEPS THIS ACTIVITY NORTHWEST OF THE FORECAST AREA OF RESPONSIBILITY
THROUGH TONIGHT. I HAVE 14 PERCENT PRECIPITATION PROBABILITIES IN THE
GRIDS THROUGH EARLY EVENING ACROSS WEST CENTRAL KANSAS. OTHERWISE, TONIGHT
WILL BE CLEAR AND PRECIPITATION FREE. LEE TROUGHING WILL CONTINUE THROUGH
THE OVERNIGHT PERIOD. SOUTHERLY WINDS IN ASSOCIATION WITH THIS FEATURE
WILL CONTINUE OVERNIGHT AS WELL. THESE WINDS WILL KEEP TEMPERATURES
MILD WITH LOWS IN THE UPPER 50S AND LOWER 60S DEG F.
TOMORROW:
ON WEDNESDAY, A LEE INDUCED LOW/TROF ACROSS SOUTHEASTERN COLORADO WILL DEEPEN
THROUGH THE AFTERNOON. THIS WILL CAUSE A WARM FRONT TO LIFT NORTHWARD
ACROSS PORTIONS OF WESTERN KANSAS. HIGHS TOMORROW IN THE WARM SECTOR
WILL BE WARM TO HOT AGAIN WITH HIGHS IN THE 86-91 DEG F RANGE. RAMPED
UP POPS IN THE AFTERNOON ACROSS THE EASTERN PORTIONS OF THE FORECAST
AREA OF RESPONSIBILITY. THERE IS SOME UNCERTAINTY IN WHERE CONVECTION
WILL DEVELOP ALONG THE FRONT AS MODELS DIFFER WITH THE FRONT POSITION.
12Z NAM DEVELOPS THUNDERSTORMS FROM LIBERAL TO HAYS, WHILE 12Z GFS KEEPS
PRECIPITATION MAINLY EAST OF HIGHWAY 183. THE WRF-NMM ECHOES THE NAM
SOLUTION, WHERE THE WRF-ARW KEEPS THE REGION DRY. DUE TO THE UNCERTAINTY,
WILL LIMIT PRECIPITATION PROBABILITIES IN THE SLIGHT CHANCE CATEGORY.
IF THE NAM SOLUTION IS CORRECT WITH MOISTURE, MLCAPE LOOKS TO BE AROUND
1500-3000 J/KG, MAINLY ACROSS SC KANSAS. 0-6 KM BULK SHEAR IS ON THE
WEAKER SIDE AT 30-35 KT. UPPER LEVEL WIND SHEAR IS VERY WEAK AT 15-30
KT. LCL`S WILL BE FAIRLY HIGH AS WELL. PUTTING THIS ALL TOGETHER, THE
OVERALL THREAT FOR HIGH END SEVERE WEATHER IS VERY LOW. THE MAIN THREAT
TOMORROW IS MARGINAL HAIL SIZE PERHAPS UP TO QUARTERS AND 50-60 MPH
OUTFLOW FROM THUNDERSTORMS.
LASTLY, LESS FIRE WEATHER CONCERNS ARE EXPECTED TOMORROW AFTERNOON AS
SLIGHTLY HIGHER DEWPOINTS AND RESULTANT HIGHER RELATIVE HUMIDITIES ARE
EXPECTED.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 354 PM CDT TUE MAY 14 2013
PRECIPITATION CHANCES, SEVERITY, AND COVERAGE WILL BE CHALLENGES IN
THE FORECAST LATE WEEK INTO THE WEEKEND...ALONG WITH AFTERNOON
TEMPERATURES WITH DRYLINE POSITION UNCERTAINTY.
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT:
A LOW AMPLITUDE SHORTWAVE TROUGH (CURRENTLY SEEN ON WATER VAPOR
SPINNING ACROSS CENTRAL CALIFORNIA) WILL BE MOVING TOWARD THE
CENTRAL HIGH PLAINS DURING THIS TIME FRAME. A WEAK FRONT MOVING
INTO EAST-CENTRAL COLORADO AND WEST-CENTRAL KANSAS WILL BE THE FOCUS
FOR THUNDERSTORMS LATE AFTERNOON WEDNESDAY...BUT THIS FRONT WILL
DISSOLVE BY WEDNESDAY NIGHT. A SMALL...LOOSELY ORGANIZED AREA OF
CONVECTION AHEAD OF THE APPROACHING WAVE MAY HOLD TOGETHER AS IT
APPROACHES FAR WEST-CENTRAL KANSAS...BUT CONFIDENCE IN THIS IS VERY
LOW AND ONLY SLIGHT CHANCE POPS ARE WARRANTED AT THIS TIME. ON
THURSDAY...THERE IS A LOT OF DISAGREEMENT ON THE 850MB
THERMODYNAMICS/MOISTURE BETWEEN THE NCEP MODELS AND THE ECMWF MODEL.
THE GFS AND NAM SHOW COPIOUS AMOUNTS OF MOISTURE AND NEAR-SATURATED
RH AT 850MB THROUGH 18Z THURSDAY WHICH IS AFFECTING THE BOUNDARY
LAYER TEMPERATURES TO THE POINT THAT THE NCEP MODELS KEEP
TEMPERATURES IN THE 70S FOR MUCH OF THE DAY. THE NCEP MODELS TEND TO
BE A BIT TOO AGGRESSIVE IN HOLDING ONTO STRATUS TOO LONG SO THE
OFFICIAL FORECAST FOR HIGHS THURSDAY WILL REFLECT MORE CLOSELY THE
ECMWF MODEL.
A DRYLINE WILL NO DOUBT BE A PREVAILING FEATURE, HOWEVER, WHICH
SHOULD FOCUS A FEW ISOLATED STORMS BY LATE AFTERNOON/EARLY
EVENING...ESPECIALLY SINCE THE AFOREMENTIONED LOW AMPLITUDE
SHORTWAVE TROUGH WILL BE PASSING JUST TO THE NORTH AIDING IN SOME
SLIGHT MID LEVEL COOLING AND OVERALL SLIGHT ENHANCEMENT OF DEEP
TROPOSPHERIC UPWARD VERTICAL MOTION. MID LEVEL FLOW AT THE BASE OF
THIS TROUGH AXIS OF 25 TO 35 KNOTS (500MB) ACROSS WESTERN KANSAS
WILL PROVIDE THE NECESSARY SHEAR ALONG WITH SOUTH-SOUTHEAST BOUNDARY
LAYER FLOW FOR SUPERCELL STORMS (ALONG WITH THE UPPER 50S TO NEAR 60
DEWPOINTS AT THE SURFACE). ANY THUNDERSTORMS LATE THURSDAY/THURSDAY
EVENING SHOULD DISSOLVE AFTER SUNSET AS INSOLATION GOES AWAY AND THE
SHORTWAVE TROUGH EXITS THE CENTRAL PLAINS.
FRIDAY AND SATURDAY:
A MUCH MORE IMPRESSIVE PACIFIC JET WILL ENTER THE SOUTHWEST/GREAT
BASIN REGION DURING THIS TIME FRAME...ENTERING THE ROCKIES AND
WESTERN PLAINS SATURDAY. THE DRYLINE WILL BE THE FOCUS FOR
THUNDERSTORMS BOTH OF THESE DAYS...BUT SATURDAY WILL BE THE BETTER
DAY OF THE TWO FOR MORE ORGANIZED SUPERCELL STORMS GIVEN THE GREATER
LOW LEVEL CONVERGENCE EXPECTED ALONG THE DRYLINE NEAR AND JUST SOUTH
OF THE SURFACE LOW. WILL HAVE CHANCE POPS NORTH OF A DIGHTON TO
LACROSSE LINE WHERE THE FORECAST SURFACE LOW WILL BE PER THE ECMWF
MODEL. SOUTH AND SOUTHWEST OF THE SURFACE LOW...HOT TEMPERATURES
WILL BE FOUND OVER A LARGER AREA THAN PREVIOUS DAYS WITH SOME UPPER
90S EVEN POSSIBLE.
SUNDAY AND BEYOND:
THE INITIAL JET STREAK WILL LIFT NORTH INTO THE NORTHERN PLAINS
LEADING TO THE FORMATION OF AN UPPER LOW...HOWEVER AN ENERGETIC JET
WILL STILL REMAIN ACROSS THE GREAT BASIN INTO THE CENTRAL ROCKIES
WHICH COULD LEAD TO DEVELOPMENT OF A SECONDARY LOW LATE SUNDAY INTO
MONDAY. SOME SLIGHT CHANCE POPS WERE INCLUDED THROUGH THE ALLBLEND
GUIDANCE ON SUNDAY AND MONDAY GIVEN THE PROSPECTS OF SOME POTENTIAL
POST-FRONTAL CONVECTION ROLLING EAST OFF THE EASTERN COLORADO
TERRAIN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1200 PM CDT TUE MAY 14 2013
VFR CIGS EXPECTED THROUGH PD. SOUTHWESTERLY WINDS 18-23 KT WILL CONTINUE
THIS AFTERNOON AND EVENTUALLY BACK SOUTHERLY 10-15 KT BY DUSK.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 60 89 60 86 / 0 20 20 10
GCK 58 92 59 88 / 10 10 10 20
EHA 56 91 58 92 / 0 10 10 20
LBL 57 92 60 92 / 0 10 10 10
HYS 59 90 60 83 / 10 20 20 10
P28 63 86 63 84 / 0 20 20 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR KSZ043>045-
062>064-075>078-084>088.
&&
$$
SYNOPSIS...SUGDEN
SHORT TERM...SUGDEN
LONG TERM...UMSCHEID
AVIATION...SUGDEN
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
252 PM CDT TUE MAY 14 2013
...UPDATE TO SHORT TERM DISCUSSION...
.SYNOPSIS...
ISSUED AT 931 AM CDT TUE MAY 14 2013
THE 14.12Z 250 HPA RAOB MAP SHOWED TWO JETS ACROSS NORTH AMERICA. THE
POLAR JET WAS LOCATED ACROSS THE NORTHERN PORTIONS OF UNITED STATES
AND INTO CANADA. THE STRONGEST WINDS WERE LOCATED FROM NOVA SCOTIA AND
INTO THE CANADIAN MARITIMES WITH MAGNITUDES AROUND 180 KT. NEXT, THE
SUBTROPICAL JET WAS LOCATED FARTHER SOUTH WITH HIGHEST MAGNITUDES AROUND
90 KT ACROSS FLORIDA. CLOSER TO KANSAS, FLOW WAS QUITE WEAK AT 15 KT. AT
500 HPA, A TROF WAS MOVING ONSHORE ACROSS CENTRAL CALIFORNIA. DAMPENING
SHORTWAVE RIDGING WAS DOWNSTREAM OF THIS FEATURE ACROSS THE 4 CORNERS
REGION. A WEAK LOW WAS LOCATED ACROSS PORTIONS OF MEXICO. A SHORTWAVE
TROF WAS MOVING ACROSS THE CENTRAL CANADIAN PRAIRIES. AN ELONGATED TROF
WAS LOCATED ACROSS THE NE U.S. AND SE CANADA. AT 700 HPA, TEMPERATURES
ACROSS SW KANSAS WERE FAIRLY WARM (10 DEG C). AT 850 HPA, 25 DEG C AT
KDDC WAS SLIGHTLY UNDER THE +2 STANDARD DEVIATION STATISTICAL MARK.
AT THE SFC, A COLD FRONT WAS LOCATED ACROSS THE NORTHERN PLAINS AND
A SURFACE LEE TROF WAS LOCATED ACROSS FAR WESTERN KANSAS.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 252 PM CDT TUE MAY 14 2013
TONIGHT:
EARLY AFTERNOON VISIBLE SATELLITE IMAGERY SHOWS A FIELD OF CUMULUS HUMILIS
CLOUDS ACROSS NORTHWEST KANSAS. THESE CLOUDS ARE IN ASSOCIATION WITH
A LEE SURFACE TROF ACROSS NORTHWEST KANSAS AND WEAK INSTABILITY. RAP
AND HRRR KEEPS THIS ACTIVITY NORTHWEST OF THE FORECAST AREA OF RESPONSIBILITY
THROUGH TONIGHT. I HAVE 14 PERCENT PRECIPITATION PROBABILITIES IN THE
GRIDS THROUGH EARLY EVENING ACROSS WEST CENTRAL KANSAS. OTHERWISE, TONIGHT
WILL BE CLEAR AND PRECIPITATION FREE. LEE TROUGHING WILL CONTINUE THROUGH
THE OVERNIGHT PERIOD. SOUTHERLY WINDS IN ASSOCIATION WITH THIS FEATURE
WILL CONTINUE OVERNIGHT AS WELL. THESE WINDS WILL KEEP TEMPERATURES
MILD WITH LOWS IN THE UPPER 50S AND LOWER 60S DEG F.
TOMORROW:
ON WEDNESDAY, A LEE INDUCED LOW/TROF ACROSS SOUTHEASTERN COLORADO WILL DEEPEN
THROUGH THE AFTERNOON. THIS WILL CAUSE A WARM FRONT TO LIFT NORTHWARD
ACROSS PORTIONS OF WESTERN KANSAS. HIGHS TOMORROW IN THE WARM SECTOR
WILL BE WARM TO HOT AGAIN WITH HIGHS IN THE 86-91 DEG F RANGE. RAMPED
UP POPS IN THE AFTERNOON ACROSS THE EASTERN PORTIONS OF THE FORECAST
AREA OF RESPONSIBILITY. THERE IS SOME UNCERTAINTY IN WHERE CONVECTION
WILL DEVELOP ALONG THE FRONT AS MODELS DIFFER WITH THE FRONT POSITION.
12Z NAM DEVELOPS THUNDERSTORMS FROM LIBERAL TO HAYS, WHILE 12Z GFS KEEPS
PRECIPITATION MAINLY EAST OF HIGHWAY 183. THE WRF-NMM ECHOES THE NAM
SOLUTION, WHERE THE WRF-ARW KEEPS THE REGION DRY. DUE TO THE UNCERTAINTY,
WILL LIMIT PRECIPITATION PROBABILITIES IN THE SLIGHT CHANCE CATEGORY.
IF THE NAM SOLUTION IS CORRECT WITH MOISTURE, MLCAPE LOOKS TO BE AROUND
1500-3000 J/KG, MAINLY ACROSS SC KANSAS. 0-6 KM BULK SHEAR IS ON THE
WEAKER SIDE AT 30-35 KT. UPPER LEVEL WIND SHEAR IS VERY WEAK AT 15-30
KT. LCL`S WILL BE FAIRLY HIGH AS WELL. PUTTING THIS ALL TOGETHER, THE
OVERALL THREAT FOR HIGH END SEVERE WEATHER IS VERY LOW. THE MAIN THREAT
TOMORROW IS MARGINAL HAIL SIZE PERHAPS UP TO QUARTERS AND 50-60 MPH
OUTFLOW FROM THUNDERSTORMS.
LASTLY, LESS FIRE WEATHER CONCERNS ARE EXPECTED TOMORROW AFTERNOON AS
SLIGHTLY HIGHER DEWPOINTS AND RESULTANT HIGHER RELATIVE HUMIDITIES ARE
EXPECTED.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 342 AM CDT TUE MAY 14 2013
.THROUGH FRIDAY...
AN ACTIVE WEATHER PATTERN IS FORECAST FOR THE REMAINDER OF THE
WEEK INTO THE WEEKEND AS A FEW DISTURBANCES MOVE THROUGH THE PLAINS.
AN UPPER LEVEL LOW WILL BE MOVING ACROSS KANSAS AS THE LONG TERM
PERIOD BEGINS ON WEDNESDAY WITH A WEAK UPPER LEVEL SHORTWAVE MOVING
ACROSS NORTHERN KANSAS ON THURSDAY. TOWARDS THE SURFACE, A COLD
FRONT IS PROGGED TO MOVE SOUTH ACROSS NEBRASKA AND INTO NORTHERN
KANSAS WEDNESDAY AFTERNOON BEFORE BECOMING STATIONARY WEDNESDAY
NIGHT. MEANWHILE, A DRYLINE WILL FORM ACROSS WESTERN KANSAS IN THE
AFTERNOON. A FEW THUNDERSTORMS MAY FORM IN THE LATE AFTERNOON ACROSS
CENTRAL AND SOUTH CENTRAL KANSAS IN THE LATE AFTERNOON INTO THE
EARLY EVENING. A FEW THUNDERSTORMS WILL THEN BE POSSIBLE ACROSS THE
AFOREMENTIONED FRONT ACROSS CENTRAL AND WEST CENTRAL KANSAS IN THE
EVENING. SKIES WILL GENERALLY BE PARTLY CLOUDY DURING THE DAY
BECOMING MOSTLY CLOUDY ACROSS MUCH OF WESTERN KANSAS DURING THE
OVERNIGHT PERIOD. ALTHOUGH, FAR WESTERN KANSAS SHOULD REMAIN MOSTLY
CLEAR THROUGHOUT THE DAY AND NIGHT. WINDS WEDNESDAY WILL GENERALLY
BE FROM A SOUTHERLY DIRECTION DURING THE DAY BECOMING LIGHT AND
VARIABLE OVERNIGHT.
THE FRONTAL BOUNDARY THEN MOVES BACK NORTH AS A WARM FRONT ON
THURSDAY WITH PARTLY CLOUDY SKIES ACROSS WESTERN KANSAS. A DRYLINE
WILL REMAIN PERSISTENT ACROSS WESTERN KANSAS AND MAY ALLOW FOR AN
ISOLATED THUNDERSTORM OR TWO TO FORM EAST OF HIGHWAY 83 THURSDAY
AFTERNOON. THESE STORMS WILL LIKELY PERISH SHORTLY AFTER SUNSET
GIVEN ABSENCE OF LARGE SCALE FORCING FOR ASCENT. ALSO, A FEW MODELS
SUGGEST A CLUSTER OF THUNDERSTORMS OR A MCS TO MOVE ACROSS NEBRASKA
OR NORTHERN KANSAS. THIS WILL NEED TO BE MONITORED IN CASE FUTURE
MODELS PLACE THIS CHANCE FARTHER SOUTH.
UPPER LEVEL RIDGING BUILDS ACROSS THE PLAINS FRIDAY WITH AN UPPER
LEVEL TROUGH DIGGING INTO THE WESTERN UNITED STATES. THERE WILL ONCE
AGAIN BE A VERY SLIGHT CHANCE OF ISOLATED THUNDERSTORMS ACROSS
CENTRAL AND SOUTH CENTRAL KANSAS IN THE AFTERNOON. HOWEVER, AN EML
BECOMES MORE PREVALENT AND MAY CAP ANY CONVECTION FROM OCCURRING.
MOSTLY CLEAR SKIES WILL BE FOUND ACROSS WESTERN KANSAS WITH A FEW
CUMULUS CLOUDS IN THE AFTERNOON.
.THIS WEEKEND INTO EARLY NEXT WEEK...
SATURDAY CONTINUES TO BE THE BEST CHANCE OF PRECIPITATION, BUT ONCE
AGAIN GENERALLY CONFINED TO CENTRAL AND SOUTH CENTRAL KANSAS. THIS
IS DUE TO THE AFOREMENTIONED UPPER LEVEL TROUGH SPINNING INTO THE
ROCKIES AND AN UPPER LEVEL JET NOSING INTO WESTERN KANSAS. TOWARDS
THE SURFACE, AN AREA OF LOW PRESSURE AND DRYLINE WILL INTENSIFY
ACROSS WESTERN KANSAS AS THE DAY PROGRESSES. LOW LEVEL CONVERGENCE
SHOULD BE STRONG ENOUGH GIVEN THE INCREASED LARGER SCALE UPWARD
VERTICAL MOTION TO PROMOTE A FEW SEVERE STORMS. MID RANGE MODELS
CONTINUE TO INDICATE AMPLE LOW LEVEL MOISTURE AHEAD OF THIS LOW WITH
ENOUGH WIND SHEAR TO PROMOTE SUPERCELL DEVELOPMENT. THUNDERSTORMS
CONTINUE ACROSS THIS AREA SATURDAY NIGHT INTO SUNDAY MORNING BUT
SHOULD BECOME LESS INTENSE DUE TO THE LACK OF DAYTIME HEATING. A
COLD FRONT IS FORECAST TO MOVE THROUGH THE AREA SUNDAY SHIFTING
WINDS TO MORE OF A NORTHERLY DIRECTION. DRIER CONDITIONS ARE THEN
SUGGESTED BY THE LONG RANGE MODELS DURING THE FIRST PART OF NEXT
WEEK AS AN UPPER LEVEL RIDGE BUILDS ACROSS THE WESTERN UNITED STATES
AND SURFACE HIGH PRESSURE BUILDS INTO THE AREA.
.TEMPERATURES...
TEMPERATURES WILL REMAIN ABOVE NORMAL THROUGHOUT THE REMAINDER OF
THE WEEK INTO THE WEEKEND. HIGHS WILL GENERALLY BE IN THE 80S WITH
THE EXCEPTION OF FRIDAY AND SATURDAY WHERE 90S WILL BE POSSIBLE.
LOWS WILL GENERALLY BE IN THE LOWER 60S WITH THE EXCEPTION OF FAR
WESTERN KANSAS WHERE UPPER 50S WILL BE POSSIBLE. MODELS SUGGEST A
SLIGHT COOL DOWN BY THE BEGINNING OF NEXT WEEK WITH HIGHS IN THE 70S
AND LOW 80S WITH LOWS IN THE 50S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1200 PM CDT TUE MAY 14 2013
VFR CIGS EXPECTED THROUGH PD. SOUTHWESTERLY WINDS 18-23 KT WILL CONTINUE
THIS AFTERNOON AND EVENTUALLY BACK SOUTHERLY 10-15 KT BY DUSK.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 60 89 60 85 / 0 20 10 20
GCK 58 92 59 86 / 10 10 10 20
EHA 56 91 58 89 / 0 10 10 10
LBL 57 92 60 88 / 0 10 10 10
HYS 59 90 60 84 / 10 20 20 30
P28 63 86 63 83 / 0 20 20 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR KSZ043>045-
062>064-075>078-084>088.
&&
$$
SYNOPSIS...SUGDEN
SHORT TERM...SUGDEN
LONG TERM...HOVORKA_42
AVIATION...SUGDEN
AREA FORECAST DISCUSSION
NWS JACKSON KY
1050 PM EDT WED MAY 15 2013
.UPDATE...
ISSUED AT 1050 PM EDT WED MAY 15 2013
A SCATTERED LINE OF CONVECTION HAS DEVELOPED OVER THE PAST FEW
HOURS...BASICALLY JUST NORTH OF A INDIANAPOLIS TO DAYTON LINE. BASED
ON THE SPEED AND MOVEMENT OF THIS CONVECTION...IT SHOULD NOT REACH
THE OUR NORTHERN COUNTIES UNTIL AT LEAST AFTER DAYBREAK. IN
FACT...THE LATEST RAP AND HRRR DO NOT SHOW MUCH OF ANYTHING IMPACTING
EASTERN KENTUCKY UNTIL EARLY TOMORROW AFTERNOON AT THE EARLIEST.
LOOKING AT THE LATEST OBS SHOWS QUITE A BIT OF LOW LEVEL DRY AIR HAS
ADVECTED INTO THE AREA THIS EVENING WITH DEWPOINTS ON THE RIDGES
STILL FALLING OVER THE PAST FEW HOURS THROUGH THE 40S. THIS ALL
SUPPORTS THE LATER ONSET OF PRECIPITATION TOMORROW AFTERNOON...IF AT
ALL. ANY CONVECTION WILL STILL LIKELY BE SPORADIC. FOR NOW...WILL CUT
BACK ON POPS THROUGH TOMORROW MORNING...AND LEAVE SOME HIGHER POPS IN
THE AFTERNOON PERIOD. FORECAST LOWS STILL LOOK ON TARGET.
UPDATE ISSUED AT 742 PM EDT WED MAY 15 2013
DEWPOINTS HAVE MIXED OUT INTO THE MID TO UPPER 40S IN MANY AREAS THIS
AFTERNOON. THIS PUTS DEWPOINTS QUITE A BIT LOWER THAN YESTERDAY AT
THIS TIME. STILL HAVE A PRETTY GOOD PRESSURE GRADIENT...BUT STARTING
TO THINK THE EASTERN VALLEYS MAY COOL OFF A BIT BETTER THAN EARLIER
ANTICIPATED GIVEN THE DRIER AIR IN PLACE. THUS...PLAN TO LOWER THE
EASTERN SHELTERED VALLEYS. THE BLUEGRASS DIDN`T MIX QUITE AS WELL
TODAY WITH DEWPOINTS STILL IN THE LOW TO MID 50S. THIS LEADS US TO
PRECIPITATION CHANCES FOR TONIGHT. WITH DEWPOINTS SO LOW
PRESENTLY...BEST RAIN CHANCES WILL LIKELY REMAIN NEAR THE AXIS OF
HIGHER DEWPOINTS ACROSS NORTHERN KENTUCKY. THUS...PLAN TO TRIM BACK
ANY PRECIPITATION CHANCES TO BASICALLY AREAS WELL NORTH OF I-64. THE
RAIN CHANCES MAY HOLD OFF WELL INTO TOMORROW BEFORE BETTER CHANCES
ARRIVE IN THE AFTERNOON. AGAIN...LATEST MODEL GUIDANCE IS PEGGING
MOST OF THE CONVECTION ACROSS THE NORTH...CLOSER TO THE SURFACE
BOUNDARY. WOULD NOT BE SURPRISED TO SEE SOUTHERN AND SOUTHEAST
KENTUCKY WITH VERY LITTLE SHOWER OR THUNDERSTORM ACTIVITY THROUGH
TOMORROW. FOR NOW WILL UPDATE TO REFINE THE LATEST THINKING WITH
TEMPERATURES AND RAIN CHANCES.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 340 PM EDT WED MAY 15 2013
18Z SFC ANALYSIS SHOWS A DECENT PRESSURE GRADIENT THROUGH EAST
KENTUCKY ATTM FROM A DEEP SFC LOW PASSING OFF TO THE NORTHEAST AND
HIGH PRESSURE OVER THE SOUTHEAST. THIS GRADIENT HAS KEPT BREEZY WEST
SOUTHWEST WINDS GOING OVER EAST KENTUCKY TODAY. AT THE SAME TIME...
CLEAR SKIES ALLOWED FOR PLENTY OF SUNSHINE. ALL TOGETHER THIS HAS
LED TO LIKELY THE WARMEST DAY OF THE YEAR THUS FAR...ONCE THE HIGHS
ARE TALLIED...WITH READINGS PRETTY UNIFORM THROUGH THE CWA IN THE
MID 80S. DEWPOINTS ARE UP FROM YESTERDAY...BY STILL NOT TOO HUMID
WITH VALUES IN THE LOW TO MID 50S.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION
OF THE FORECAST AS THEY ALL TAKE A SOUTHERN STREAM LOW EAST FROM THE
SOUTHERN PLAINS TONIGHT AND THURSDAY. THIS WILL OPEN UP AS IT
APPROACHES KENTUCKY ON THURSDAY...KNOCKING DOWN THE MODERATE RIDGING
THAT WE ENJOYED TODAY. AS THE LOW OPENS UP...ITS ENERGY WILL STREAM
OVER KENTUCKY AND KEEP THE WEATHER UNSETTLED INTO FRIDAY MORNING.
GIVEN THE MODEL SIMILARITIES HAVE MAINLY FOLLOWED THE HIGHER
RESOLUTION NAM12 FOR WEATHER SPECIFICS THROUGH THE FORECAST.
SENSIBLE WEATHER WILL FEATURE ANOTHER MILD NIGHT...BUT NOT QUITE AS
BREEZY. DO EXPECT A SMALL TO MODERATE RIDGE TO VALLEY SPLIT WITH
SOME OF THE SHELTERED LOCATIONS LIKELY BOTTOMING OUT AROUND MIDNIGHT
BEFORE SEEING THEIR TEMPS RISE A TAD TOWARD DAWN. AGAIN...JUST A HINT
OF PATCHY FOG CAN BE EXPECTED IN THE RIVER VALLEYS AND NEAR THE
LAKES. A BACK DOOR COLD FRONT WILL SLIP TOWARD THE AREA LATE TONIGHT
FROM THE NORTH. FROM THIS SCATTERED SHOWERS OR A STRAY THUNDERSTORM
WILL BE POSSIBLE BY DAWN...MAINLY NORTH OF THE MOUNTAIN PARKWAY. THIS
BOUNDARY...STALLING JUST TO THE NORTH OF THE CWA...AND THE APPROACH
OF THE UPPER LOW FROM THE WEST WILL LIKELY BE ENOUGH FOR SCATTERED TO
NUMEROUS SHOWERS AND THUNDERSTORMS DEVELOPING BY MIDDAY THURSDAY.
EXPECT PRETTY GOOD COVERAGE THROUGH THE AFTERNOON...BUT THE DIRECT
HITS MAYBE AROUND 50 PERCENT FOR ANY SPECIFIC LOCATION. THE DIURNAL
NATURE OF THE CONVECTION WILL MEAN A TAPERING BACK TO MAINLY ISOLATED
SHOWERS BY MIDNIGHT AND ANOTHER MILD NIGHT WITH A POTENTIAL FOR
PATCHY FOG IN THE VALLEYS BY DAWN FRIDAY.
FOR TEMPERATURES...USED THE CONSSHORT AS A STARTING POINT WITH ONLY
MINOR ADJUSTMENTS BASED ON TERRAIN TONIGHT. AS FOR POPS...ENDED UP
HIGHER THAN MOS THROUGH THE PERIOD GIVEN THE ANTICIPATED GOOD
COVERAGE ON THURSDAY AND LINGERING CHANCES INTO THAT NIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 245 PM EDT WED MAY 15 2013
MODELS IN GOOD AGREEMENT FOR THE LONG TERM PORTION OF THE FORECAST
WITH THE OVERALL PATTERN...AND WITH THE EXPECTATION OF ABOVE NORMAL
TEMPERATURES. AT THE BEGINNING OF THE PERIOD A FRONTAL BOUNDARY IS
FORECAST TO BE OVER SOUTHERN OHIO. THIS IDEA IS SUPPORTED BY
OPERATIONAL MODELS...AS WELL AS THE SREF AND GFS ENSEMBLE. THE
FRONTAL BOUNDARY WILL MEANDER IN THE OH VALLEY THROUGH THE UPCOMING
WEEKEND...AND WILL REMAIN THE FOCUS FOR CONVECTION. FRONT MAY SLIP
INTO NORTHERN PART OF FORECAST AREA DURING WEEKEND...BUT DO NOT
EXPECT IT TO GET MUCH FURTHER SOUTH THAN THAT. A SHORT WAVE TROF
MOVES EAST FOR THE FIRST PART OF THE WEEKEND...THOUGH THERE IS NOT
GOOD MODEL AGREEMENT ON THE IMPACT OF THIS. THE EXPECTATION IS THAT
THIS MAY INCREASE PRECIPITATION CHANCES FOR EARLY PART OF THE
WEEKEND.
BY MONDAY PRECIPITATION CHANCES SHOULD BE ON THE DECREASE AS UPPER
RIDGING BUILDS ACROSS THE AREA...AND THE SURFACE FRONT LIFTS NORTH.
MODELS ARE IN GOOD AGREEMENT WITH THE UPPER LOW OVER THE NORTHERN
PLAINS EARLY NEXT WEEK. IN FACT FOR THE 12Z TUESDAY FORECAST THE 12Z
GFS...00Z ECMWF AND 00Z GFS ENSEMBLE MEAN ALL HAVE THE 5H LOW IN THE
VICINITY OF THE MN SD BORDER...WITH THE 12Z ECMWF PLACING IT NEAR
THE IA SD NE TRI STATE AREA. WITH THE NORTHERN PLAINS MID AND UPPER
LOW CLOSING OFF THE ASSOCIATED SURFACE LOW AND COLD FRONT WILL BE
SLOW TO MOVE EAST. AT THIS TIME IT APPEARS THE MOST LIKELY SCENARIO
WILL BE THAT THE COLD FRONT WILL MOVE INTO THE AREA SOMETIME ON
WEDNESDAY...WITH AN INCREASED CHANCE OF SHOWERS AND THUNDERSTORMS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 742 PM EDT WED MAY 15 2013
VFR CONDITIONS WILL HOLD THROUGH THE TAF FORECAST PERIOD. A THREAT OF
THUNDERSTORMS WILL ARRIVE FROM THE NORTH LATE TOMORROW MORNING INTO
THE AFTERNOON. AT THIS TIME...TOO MUCH UNCERTAINTY TO GO WITH A
PREVAILING THUNDERSTORM GROUP AS THE THUNDERSTORMS COULD STAY NORTH
OR NOT IMPACT THE TAF SITES. THUS...GOING TO ONLY INCLUDE A VCTS AT
KJKL FOR NOW. OTHERWISE...LIGHT WINDS TONIGHT WILL BECOME
SOUTHWESTERLY AT 5 TO 10 KNOTS ON THURSDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KAS
SHORT TERM...GREIF
LONG TERM...SBH
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
922 PM EDT WED MAY 15 2013
.SYNOPSIS...
HIGH PRESSURE REMAINS CENTERED OFF THE MID ATLANTIC COAST THROUGH
FRIDAY. A WEAK FRONT APPROACHES THE AREA FROM THE NORTH THURSDAY
AFTERNOON THEN SETTLES OVER THE AREA FRIDAY INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
THE LATEST SURFACE ANALYSIS INDICATES A ~1022MB SURFACE HIGH
CENTERED OVER THE EAST-CENTRAL GULF COAST, WITH A SURFACE RIDGE
AXIS EXTENDING NE JUST OFF THE SOUTHEAST COAST. ALOFT, A RATHER
PROGRESSIVE NORTHERN STREAM FLOW EXISTS, WITH QUASI-ZONAL FLOW
ACROSS THE NORTHERN TIER OF STATES. MEANWHILE, WEAK SHORTWAVE
RIDGING HAS DEVELOPED ACROSS THE SOUTHEAST AHEAD OF CLOSED UPPER
LOW WHICH CONTINUES TO SLOWLY MEANDER ACROSS THE SOUTHERN PLAINS.
A WEAK DISTURBANCE DROPPING SE OF THE LOWER GRT LAKES HAVE
TRIGGERED A FEW ISOLATED SHRAS THIS EVENING, MAINLY ALONG AND
JUST SOUTH OF THE MASON-DIXON LINE INVOF FNTL BNDRY DRAPED NW-SE
FM SOUTH CENTRAL PA TO OH VLY THIS EVE. HRRR CONTINUES TO WEAKEN
THIS ACTIVITY JUST TO OUR NORTH, THOUGH POTENTIAL DOES EXIST FOR
AN ISOLATED SHRA OR TWO OVER FAR NORTHERN PART OF DORCHESTER,
WICOMICO, AND WORCESTER COUNTIES (US-50 AND NORTH) THROUGH ABOUT
6Z/2A OR SO BEFORE IT AND THE ASSD WARM FRONT CLEAR THE NORTHERN
MID-ATLANTIC COAST LATE TONIGHT. OTHERWISE, LOOK FOR A MILD,
COMFORTABLE OVERNIGHT, UNDER A CLEAR TO PARTLY CLOUDY SKY. EARLY
MORNING LOW TEMPS MAINLY IN THE L/M60S.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
FNTL BNDRY FM THE N BEGINS TO PUSH SLOLY S THU...REACHING NRN
AREAS OF FA IN THE AFTN...THEN TO THE S THU NGT INTO FRI. NOT THE
BEST FORCING OR DYNAMICS FOR ORGANIZED CNVTN...THOUGH SOME POOLING
OF SFC-LO LVL DEWPTS COMBINED W/ HEATING PTNTLLY ENOUGH FOR
ISOLD/SCT CNVTN. WILL CARRY 20-40% POPS ACRS THE FA THU AFTN INTO
THU NGT. THE BNDRY SHIFTS S TO NR OR JUST S OF THE NC/VA BRDR ON
FRI...W/ PSBL FOCUS FOR ANY PCPN FM CNTRL/SRN VA INTO NE NC. WHILE
ENOUGH TIME FOR DECENT WRMG ON THU (BEFORE THE BNDRY REACHES THE
FA)...WILL BE ABLE TO HAVE TEMPS REACH THE 80S XCP RIGHT AT THE
CST (ON THE ERN SHR). PSNY THU...THEN VRB CLDS OR MCLDY THU NGT
INTO FRI.
THE BNDRY TO RMN NRLY STNRY INVOF NRN NC LT FRI THROUGH SAT. SFC
HI PRES PASSING BY N AND THROUGH NEW ENG WILL LEAD TO ONSHR
WINDS...CONTD VRB CLDS OR MCLDY CONDS AND LO PROB FOR PCPN. HI
TEMPS SAT FM ARND 70F AT THE CST...TO MNLY THE M/U70S INLAND.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
A WEAK FRONTAL BOUNDARY WILL LINGER ACROSS THE MID-ATLANTIC SUNDAY.
THIS IS IN ADDITION TO A WEAK UPPER DISTURBANCE PASSING OVERHEAD
WILL PRODUCE A CHANCE FOR SHOWERS AND THUNDERSTORMS. AN H5 RIDGE
AXIS BUILDS OVER THEN EASTERN U.S. MON-WED OF NEXT WEEK. MODELS SHOW
A LOT OF UNCERTAINTY AS TO JUST HOW MUCH SHOWER/TSTM ACTIVITY WILL
OCCUR EARLY NEXT WEEK. DUE TO A LACK OF A TRIGGER TO GET ORGANIZED
TSTMS GOING...WILL LIMIT PCPN CHANCES TO THE 20-30% RANGE REACH DAY.
TEMPS WILL REMAIN ON THE WARM/MILD SIDE THROUGH THE PERIOD WITH
HIGHS IN THEN 70S AND 80S AND LOWS IN THE 60S.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
SW WINDS WILL OCCUR OVER THE REGION TONIGHT WITH GUSTY WINDS 15 TO
20 KT ALONG THE COAST. WINDS WITH GENERALLY STAY BRISK ALONG THE
COAST THRU MUCH OF THE NIGHT. VFR CONDS OVER THE CWA WITH MOSTLY CLR
SKIES OR HIGH THIN CLOUDS. A SLOW MOVG COLD FRONT WILL LIE WELL
NORTH OF THE AREA LATE TONIGHT AND THU. SW WINDS TONIGHT WILL SHIFT
TO THE W-WNW ON THU. MOSTLY DRY CONDS ON THU BUT INCREASING CLOUDS
TO THE NORTH MAY AFFECT SBY AND RIC IN THE LATE AFTN/EVENING.
THE BACK DOOR COLD FRONT WILL SLOWLY DRIFT SWD THU AFTN THROUGH
THE END OF THE WEEK...BEFORE STALLING OVER NC AT THE BEGINNING OF
THE WEEKEND. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL
BE POSSIBLE EACH AFTERNOON AND EVENING THROUGH THE END OF THE
WEEK.
&&
.MARINE...
S-SW FLOW CONTINUES ACROSS THE MARINE AREA THROUGH LATE THIS EVENING
WITH MARGINAL SMALL CRAFT CONDITIONS (SAVE THE SOUTHERN COASTAL
WATERS). WILL LEAVE CURRENT HEADLINES UNCHANGED. WINDS TURN SW TO W
LATE TONIGHT AND DECREASE IN ADVANCE OF A BACKDOOR COLD FRONT THAT
SLOWLY SAGS SOUTHWARD THURS...CROSSING THE WATERS THURS NIGHT INTO FRI
BEFORE STALLING OVER THE CAROLINAS. WINDS WILL SHIFT FROM THE SW TO
THE N/NE POST FRONTAL...BUT EXPECTED TO REMAIN BELOW SCA THRESHOLDS.
E-SE WINDS LESS THAN 15 KT ARE EXPECTED OVER THE WEEKEND.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 AM EDT THURSDAY FOR ANZ630>634-
638.
SMALL CRAFT ADVISORY UNTIL 7 AM EDT THURSDAY FOR ANZ650-652-
654.
&&
$$
SYNOPSIS...ALB
NEAR TERM...ALB
SHORT TERM...ALB
LONG TERM...JDM
AVIATION...JEF
MARINE...JDM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
725 PM EDT WED MAY 15 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 409 PM EDT WED MAY 15 2013
WV IMAGERY AND RUC ANALYSIS INDICATED WNW MID/UPPER LEVEL FLOW
THROUGH THE NRN GREAT LAKES ON THE SRN FLANK OF A TROUGH OVER NRN
ONTARIO TO THE SRN END OF JAMES BAY. A WEAK SHORTWAVE TROUGH
OVER THE SE CORNER OF MANITOBA SUPPORTED AN AREA OF MID CLOUDS AND
SOME SCT/ISOLD -SHRA INTO NW MN. AT THE SFC...A TIGHT PRES GRADIENT
PERSISTED BTWN A 995 MB LOW BTWN JAMES BAY AND LAKE SUPERIOR AND A
RIDGE FROM THE NRN PLAINS INTO SRN MN. WNW WINDS HAVE GUSTED AT OR
ABOVE 30 MPH OVER MUCH OF UPPER MI AND TO NEAR 45 MPH WHERE TERRAIN
HAS BOOSTED THE WINDS AT CMX. SUNSHINE WITH TEMPS INTO THE LOWER TO
MID 70S AND DEEP MIXING TO AROUND 750 MB HAS LOWERED DEWPOINTS TO
AROUND 30F WITH RH VALUES TO AROUND 20 PCT. THE COMBINATION OF THE
DRY AIR WINDS HAS RESULTED IN CRITICAL FIRE WEATHER CONDITIONS.
TONIGHT...AS THE PRES GRADIENT WEAKENS AND DAYTIME HEATING
SUBSIDES...WINDS WILL DIMINISH QUICKLY THIS EVENING AND BECOME LIGHT
OVERNIGHT. HIGHER RES SHORT RANGE MODELS SUGGEST THAT THE BEST
CHANCES OF PCPN ASSOCIATED WITH THE MANITOBA SHORTWAVE OVER THE SW
HALF OF UPPER MI. EVEN THERE...WITH DRY LOW LEVELS AND WEAK FORCING
WITH THE SHRTWV MAINLY JUST SPRINKLES AT MOST WOULD BE EXPECTED.
SO...ONLY A SMALL AREA OF SLIGHT CHANCE POPS WERE INCLUDED.
THURSDAY...EXPECT COOLER CONDITIONS OVER THE NORTH HALF OF UPPER MI
WITH NRLY WINDS BEHIND A COLD FRONT MOVING THROUGH THE AREA LATE
TONIGHT. WITH 850 MB TEMPS RANGING FROM AROUND 4C NORTH TO TO 9C
SOUTH...TEMPS SHOULD RANGE FROM THE LOWER 50S NEAR LAKE SUPERIOR TO
THE LOWER 70S INLAND SOUTHWEST. SUNSHINE AND FAVORABLE MIXING WILL
AGAIN DROP DEWPOINTS INTO THE LOWER 30S WITH RH VALUES TO AROUND 25
PERCENT SOUTH. HOWEVER...WITH WINDS ONLY TO AROUND 10 MPH...THE
WILDFIRE RISK WILL BE LOWER THAN TODAY.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 440 PM EDT WED MAY 15 2013
TEMPS WILL HOLD STEADY IN THE 60S ON FRIDAY AND SATURDAY...WITH A
WARM UP FOR SUNDAY AS SSE WINDS INCREASE AHEAD OF LOW PRESSURE
NEARING FROM THE CENTRAL PLAINS. AT THIS POINT THE STRONGER WINDS
LOOK TO BE ASSOCIATED WITH INCREASED DEW POINTS...LIMITING
SIGNIFICANT FIRE CONCERNS.
THERE IS A LOT OF UNCERTAINTY WITH THE MID TO LONGER RANGE OF THIS
FORECAST...WITH THE TRACK AND TIMING OF THE SLOW MOVING LOW PRESSURE
SYSTEM. WITH THAT SAID...THERE IS A SLIGHT CHANCE OF SHOWERS AND
THUNDERSTORMS IN THE FORECAST FROM SATURDAY ON /MAINLY WEST/.
THUNDERSTORM CHANCES ARE NOT THAT IMPRESSIVE. IT LOOKS LIKE THE BEST
CHANCE FOR SHOWERS AND THUNDERSTORMS ACROSS THE ENTIRE CWA WILL HOLD
OFF UNTIL MONDAY...WITH THE SFC LOW IS SET UP OVER THE EASTERN
DAKOTAS AND WESTERN MN. THE SYSTEM CONTINUES TO SLOW DOWN...AS IT
WAS ORIGINALLY EXPECTED TO CROSS UPPER MI ON SUNDAY...AT LEAST OF A
COUPLE OF DAYS AGO. NOW IT LOOKS TO HOLD OFF UNTIL TUESDAY AT THE
EARLIEST /12Z ECMWF SOLUTION/. THE GFS IS EVEN SLOWER...AND HAS THE
500MB LOW OVER ND TUESDAY AFTERNOON RETROGRADING AND CONSOLIDATING
WITH THE DEEP LOW PUSHING INTO THE PACIFIC NORTHWEST. WILL OPT FOR
FOR A SOLUTION CLOSER TO THE ECMWF AT THIS POINT...WITH LOWER
CONFIDENCE IN THE FORECAST BEYOND SUNDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 723 PM EDT WED MAY 15 2013
WITH LOSS OF DAYTIME HEATING/MIXING...EXPECT DIMINISHING WINDS THIS
EVNG. ALTHOUGH A WEAK LO PRES TROF WL PASS UPR MI TNGT AND A -SHRA
IS PSBL MAINLY AT IWD...DRYNESS OF AIRMASS IN PLACE INDICATES VFR
CONDITIONS WL PREVAIL. HI PRES WL BUILD OVER THE UPR LKS ON THU...
BRINGING CONTINUED VFR CONDITIONS AND LIGHTER N-E WINDS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 PM EDT WED MAY 15 2013
EXPECT WINDS WITH GUSTS 25 KNOTS TO DIMINISH TONIGHT AS HIGH PRES
BUILDS INTO THE REGION. HIGH PRESSURE WILL EXPAND ACROSS GREAT LAKES
INTO THE WEEKEND WITH EAST-SOUTHEAST WINDS AT OR BLO 25 KTS. WINDS
BECOME SOUTHERLY LATE THIS WEEKEND AHEAD OF LOW PRESSURE TROUGH
PUSHING IN FROM NORTHERN PLAINS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
RED FLAG WARNING UNTIL 9 PM EDT /8 PM CDT/ THIS EVENING FOR
MIZ002-004>006-009>014-084-085.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
446 PM EDT TUE MAY 14 2013
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 422 PM EDT TUE MAY 14 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A ZONAL MID/UPPER LEVEL
PATTERN ACROSS THE NRN CONUS WITH A PROMINENT SHORTWAVE TROUGH NEAR
WINNIPEG. AT THE SFC...A 992 MB LOW WAS ALSO LOCATED OVER SE
MANITOBA WITH A COLD FRONT THROUGH NW MN INTO ERN SD. A WARM FRONT
STRETCHED FROM CNTRL MN INTO SRN WI. RADAR INDICATED WEAK RETURNS
WITH VERY LIGHT SHOWERS(VIRGA OR SPRINKLES) THROUGH CNTRL UPPER MI
AS THE BAND OF 310K (750-600 MB)ISENTROPIC LIFT MOVES THROUGH THE
AREA. SATELLITE SHOWED SKIES CLEARING OVER THE WEST AS DRIER AIR
BEHIND THE PCPN BAND MOVES IN.
TONIGHT...MODELS SUGGEST THAT AS THE MID LEVEL SHRTWV TROUGH AND
ASSOCIATED SFC TROUGH MOVES THROUGH UPPER MI SOME SHOWERS MAY
DEVELOP...MAINLY ACROSS NRN LAKE SUPERIOR AND POSSIBLY INTO THE NRN
PORTIONS OF UPPER MI ON THE SRN TAIL OF THE STRONGER QVECTOR CONV
AND FAVORABLE ISENTROPIC ASCENT JUST AHEAD OF THE SFC TROUGH. MUCAPE
VALUES (LIFTING FROM NEAR 750 MB) OF 500-1000 J/KG STILL SUPPORT A
CONDITIONAL THREAT OF TSRA. ALTHOUGH EFFECTIVE SHEAR VALUES ARE
MARGINAL (20-30 KT) SOME SMALL HAIL MAY BE POSSIBLE WITH ANY TSRA
THAT DEVELOP. CONFIDENCE IN SHRA/TSRA DEVELOPMENT IS LIMITED AS
MODELS HAVE TRENDED TOO HIGH WITH LOW LEVEL MOISTURE AVAILABILITY.
SO...ONLY LOWER END CHANCE POPS WERE INCLUDED.
WED...MODEL SOUNDINGS SHOW STRONG MID-LVL DRYING/SUBSIDENCE IN THE WAKE OF
THE COLD FRONT AS 850 MB TEMPS DROP TO AROUND 5C EARLY WED BUT
REBOUND TO TO AROUND 8C-9C WED AFTERNOON. MIXING HEIGHTS ABOVE 800
MB SHOULD MIX A SIGNIFICANT ENOUGH PORTION OF THE VERY DRY 800-650 MB
LAYER TO DROP DEWPOINTS INLAND TO AROUND 30F. WITH TEMPS INTO THE
LOWER TO MID 70S...RH VALUES WILL DROP TO AROUND 20 PERCENT. NW WIND
SHOULD ALSO INCREASE TO AROUND 15 MPH WITH GUSTS OF 20-25 MPH IN THE
AFTERNOON. SO...A FIRE WEATHER WATCH WAS ISSUED FOR MOST OF INLAND
WEST AND CENTRAL UPPER MICHIGAN.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 444 PM EDT TUE MAY 14 2013
OUR STRONGER WINDS WILL QUICKLY DIMINISH WEDNESDAY NIGHT...EVEN WITH
A REINFORCING SFC TROUGH STRETCHED W-E OVER LAKE SUPERIOR AT 06Z
THURSDAY SINKING SE ACROSS EASTERN UPPER MI BY 12Z THURSDAY. WITH
THAT RH VALUES SHOULD QUICKLY REBOUND TO 35 PERCENT OR BETTER BY 03Z
THURSDAY.
BEHIND THE EXITING TROUGH...HIGH PRESSURE SITUATED OVER S CENTRAL
CANADA WEDNESDAY NIGHT WILL PUSH ACROSS THE CWA AND BE DIRECTLY
OVERHEAD DURING THE DAY THURSDAY...BEFORE SLOWLY EXITING EASTERN
UPPER MI/LAKE SUPERIOR THURSDAY NIGHT INTO FRIDAY.
THURSDAY WILL BE DRY ONCE AGAIN FOR SOUTH CENTRAL AREAS...AND IN
PARTICULAR GOGEBIC...ONTONAGON...IRON...AND DICKINSON COUNTIES.
WINDS WILL BE MUCH LIGHTER THAN WEDNESDAY GIVEN THE DIMINISHED
PRESSURE GRADIENT...AVERAGING 5-10KTS. A WILDFIRE POTENTIAL
STATEMENT MAY BE NEEDED...BUT IS REALLY MARGINAL GIVEN THE NEAR
NORMAL TEMPS FOR THIS TIME OF YEAR...AND LIGHTER WINDS. THE WINDS
ARE THE MAIN THREAT THIS TIME OF YEAR...GIVEN THAT THE MAIN CARRIER
OF FIRES IS THE DRY GRASSES.
THE LINGERING HIGH OVER THE EAST WILL KEEP DRIER AIR IN
PLACE...LIMITING THE POTENTIAL FOR ANY SHOWERS TO MOVE MUCH EAST OF
A LINE FROM MQT TO ESC UNTIL SATURDAY MORNING.
EXPECT INCREASED S FLOW STARTING FRIDAY NIGHT...IN ADVANCE OF A
NEARING LOW DEVELOPING ACROSS THE CENTRAL PLAINS STATES. SEVERAL
WARMER NIGHTS ARE FIGURED WITH MID 40S FOR LOWS FRIDAY NIGHT...NEAR
50F SATURDAY NIGHT AND AGAIN SUNDAY NIGHT. THE LATEST TREND IS TO
MINIMIZE THE POTENTIAL FOR THUNDERSTORM ACTIVITY UNTIL THE SFC LOW
AND 500MB TROUGH GET A BIT CLOSER TO THE CWA...AROUND OR AFTER THE
SUNDAY TIME PERIOD. EXPECT THE ELONGATED LOW STRETCHING FROM
NORTHEAST MN TO N TX AT 18Z SUNDAY /ECMWF FARTHEST EAST/ TO
CONSOLIDATE OVER WESTERN UPPER MICHIGAN SUNDAY EVENING. THE 12Z GFS
DOES NOT BRING THE LOW TO WESTERN UPPER MI UNTIL TUESDAY. NEEDLESS
TO SAY THIS WILL BE A SLOW MOVING SYSTEM...WITH SEVERAL ROUNDS OF
PRECIP ROTING INTO THE REGION. WILL GO WITH A MODEL CONSENSUS BEYOND
SUNDAY...GIVEN THE LARGER DISCREPANCIES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 139 PM EDT TUE MAY 14 2013
VFR CONDITIONS SHOULD PREVAIL AT ALL THREE TAF SITES THROUGH THE
FORECAST PERIOD. A PERIOD OF MID CLOUDS IS EXPECTED THROUGH MID
AFTERNOON AS A BAND OF DISSIPATING LIGHT SHOWERS OR SPRINKLES MOVES
THROUGH WRN UPPER MI. ANOTHER ROUND OF ISOLD SHRA/TSRA POSSIBLE THIS
EVENING AS PRIMARY SFC FRONT ARRIVES. PLENTY OF DRY AIR REMAINS OVER
THE AREA WHICH MAY INHIBIT DEVELOPMENT. WENT FOR SHORT PERIOD OF
VCSH AT CMX WHICH IS IN BEST PROXIMITY TO A DISTURANCE TO THE NORTH
AND LIFT AHEAD OF A WARM FRONT...THEN SHARP DRYING/CLEARING
OVERNIGHT TONIGHT. WILL ALSO SEE GUSTY WEST WINDS IN WAKE OF THE
FRONT...STRONGEST AT THE MORE EXPOSED KCMX.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 422 PM EDT TUE MAY 14 2013
SOUTHERLY FLOW WAS INCREASING AHEAD OF A LOW PRESSURE SYSTEM MOVING
EAST THROUGH SOUTHERN CANADA. WINDS INCREASE TO 25 KTS TONIGHT INTO WED
BUT WILL BE LIMITED AS LOW LEVEL WARM AIR ADVECTION RESULTS IN
INCREASING STABILITY. WINDS ARE EXPECTED TO REMAIN BELOW
30KTS LATER THIS WEEK AND INTO THE WEEKEND. AFTER COOL AND WINTRY
WEATHER FOR THE SPRING SO FAR...SUMMERTIME WEATHER IS BECOMING MORE
COMMON. THUNDERSTORMS ARE POSSIBLE TONIGHT AND ENDING BY
EARLY WEDNESDAY. ANOTHER ROUND OF THUNDERSTORMS WILL BE POSSIBLE
WEST ON SATURDAY/SATURDAY NIGHT...AND ACROSS ALL OF LAKE SUPERIOR
SUNDAY THROUGH MONDAY MORNING.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FIRE WEATHER WATCH FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY
EVENING FOR MIZ002-004>006-009>014-084-085.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
423 PM EDT TUE MAY 14 2013
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 422 PM EDT TUE MAY 14 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A ZONAL MID/UPPER LEVEL
PATTERN ACROSS THE NRN CONUS WITH A PROMINENT SHORTWAVE TROUGH NEAR
WINNIPEG. AT THE SFC...A 992 MB LOW WAS ALSO LOCATED OVER SE
MANITOBA WITH A COLD FRONT THROUGH NW MN INTO ERN SD. A WARM FRONT
STRETCHED FROM CNTRL MN INTO SRN WI. RADAR INDICATED WEAK RETURNS
WITH VERY LIGHT SHOWERS(VIRGA OR SPRINKLES) THROUGH CNTRL UPPER MI
AS THE BAND OF 310K (750-600 MB)ISENTROPIC LIFT MOVES THROUGH THE
AREA. SATELLITE SHOWED SKIES CLEARING OVER THE WEST AS DRIER AIR
BEHIND THE PCPN BAND MOVES IN.
TONIGHT...MODELS SUGGEST THAT AS THE MID LEVEL SHRTWV TROUGH AND
ASSOCIATED SFC TROUGH MOVES THROUGH UPPER MI SOME SHOWERS MAY
DEVELOP...MAINLY ACROSS NRN LAKE SUPERIOR AND POSSIBLY INTO THE NRN
PORTIONS OF UPPER MI ON THE SRN TAIL OF THE STRONGER QVECTOR CONV
AND FAVORABLE ISENTROPIC ASCENT JUST AHEAD OF THE SFC TROUGH. MUCAPE
VALUES (LIFTING FROM NEAR 750 MB) OF 500-1000 J/KG STILL SUPPORT A
CONDITIONAL THREAT OF TSRA. ALTHOUGH EFFECTIVE SHEAR VALUES ARE
MARGINAL (20-30 KT) SOME SMALL HAIL MAY BE POSSIBLE WITH ANY TSRA
THAT DEVELOP. CONFIDENCE IN SHRA/TSRA DEVELOPMENT IS LIMITED AS
MODELS HAVE TRENDED TOO HIGH WITH LOW LEVEL MOISTURE AVAILABILITY.
SO...ONLY LOWER END CHANCE POPS WERE INCLUDED.
WED...MODEL SOUNDINGS SHOW STRONG MID-LVL DRYING/SUBSIDENCE IN THE WAKE OF
THE COLD FRONT AS 850 MB TEMPS DROP TO AROUND 5C EARLY WED BUT
REBOUND TO TO AROUND 8C-9C WED AFTERNOON. MIXING HEIGHTS ABOVE 800
MB SHOULD MIX A SIGNIFICANT ENOUGH PORTION OF THE VERY DRY 800-650 MB
LAYER TO DROP DEWPOINTS INLAND TO AROUND 30F. WITH TEMPS INTO THE
LOWER TO MID 70S...RH VALUES WILL DROP TO AROUND 20 PERCENT. NW WIND
SHOULD ALSO INCREASE TO AROUND 15 MPH WITH GUSTS OF 20-25 MPH IN THE
AFTERNOON. SO...A FIRE WEATHER WATCH WAS ISSUED FOR MOST OF INLAND
WEST AND CENTRAL UPPER MICHIGAN.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 625 AM EDT TUE MAY 14 2013
MODEL SNDGS SHOW GOOD MID-LVL DRYING/SUBSIDENCE IN THE WAKE OF THE
COLD FRONT AS 8H TEMPS DROP TO 8-9C. MODELS INDICATE PW VALUES DROP
BLO .5 INCH OR OR 60-70 PERCENT OF NORMAL. GFE MIXED DEWPOINT TOOL
FOR THE NAM AND GFS SHOWS POTENTIAL FOR DEWPOINTS TO DROP INTO THE
LOWER TO MID 20S OVER THE WRN INTERIOR. LOOKING AT HOW DRY MODEL
SNDGS ARE ABV 825 MB THESE DEWPOINTS WOULD NOT BE FAR-FETCHED AT
ALL...ESPECIALLY IF WE MIX NEAR 800 MB. WITH T/TD OF 74/24 MIN RH
VALUES WOULD DROP NEAR 15 PERCENT. NW WIND SHOULD STAY JUST BLO RED
FLAG CRITERIA WITH SUSTAINED WINDS AROUND 15 KT AND GUSTS AROUND 20
KT. HOWEVER IF PCPN IS LIMITED TUE NIGHT...FIRE DANGER WILL
DEFINITELY BE A CONCERN FOR WEDNESDAY. DAY SHIFT MAY NEED TO
COORDINATE WITH FIRE WX USERS TODAY TO SEE IF FIRE WEATHER WATCH MAY
BE NEEDED FOR WED AFTERNOON.
MODELS SHOW A TROUGH MOVING THROUGH THE AREA WED NIGHT BUT NO PCPN
IS EXPECTED FM THIS FEATURE AS THE AIRMASS AND FCST WILL REMAIN DRY
INTO FRI MORNING UNDER CONFLUENT FLOW ALOFT AND BUILDING 5H RDG
HEIGHTS. EXPECT THE SURFACE RIDGE OF HIGH PRESSURE TO BE DIRECTLY
OVERHEAD ON THURSDAY WHICH WILL RESULT IN LIGHT WINDS AND LAKE
BREEZES CIRCULATIONS.
INCREASING WAA/ISENTROPIC LIFT FRI AFTERNOON INTO SAT MORNING
SPREADING FM WEST TO EAST ACROSS THE CWA WILL BRING AN INCREASED CHC
OF SHOWERS FRI NIGHT INTO SATURDAY MORNING FOR MUCH OF THE CWA. FCST
SHOWALTER INDICES AND MUCAPE VALUES INDICATE CHC OF THUNDERSTORMS
DURING THIS TIME WILL BE MAINLY CONFINED TO THE WEST HALF OF THE CWA
LATE FRI NIGHT INTO SAT MORNING. AS 850 MB WARM FRONT LIFTS NORTH OF
THE CWA BY SATURDAY AFTERNOON...MODEL SNDGS SUGGEST ENVIRONMENT WILL
BECOME CAPPED BY WARMER/DRIER AIR AND THUS EXPECT A LULL IN SHOWER
ACTIVITY FOR SAT AFTERNOON INTO AT LEAST SAT EVENING.
BOTH THE 00Z ECMWF AND GFS INDICATE A SHORTWAVE LIFTING OUT FM BASE
OF UPR TROUGH OVER THE SRN PLAINS AND TOWARD THE UPPER MS VALLEY ON
SUNDAY. THIS SHORTWAVE WILL HELP PUSH FRONTAL BOUNDARY CLOSER TO THE
UPPER MS VALLEY AND OUR WRN CWA ESPECIALLY SUN AFTERNOON. 8H THETA-E
MAXIMUM ALONG THE FRONTAL BOUNDARY AND CORRESPONDING INCREASE IN
INSTABILITY (MLCAPES REACH 700-1200 J/KG OVER WEST HALF) WILL
WARRANT AN INCREASED CHC OF SHRA AND TSRA FOR SUNDAY ESPECIALLY OVER
THE WEST HALF. WILL MAINTAIN HIGH CHC POPS FOR SHRA/TSRA SUN NIGHT
INTO MONDAY ACROSS THE CWA AS MAIN SHORTWAVE AND ASSOC COLD FRONT
MOVE ACROSS THE UPPER GREAT LAKES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 139 PM EDT TUE MAY 14 2013
VFR CONDITIONS SHOULD PREVAIL AT ALL THREE TAF SITES THROUGH THE
FORECAST PERIOD. A PERIOD OF MID CLOUDS IS EXPECTED THROUGH MID
AFTERNOON AS A BAND OF DISSIPATING LIGHT SHOWERS OR SPRINKLES MOVES
THROUGH WRN UPPER MI. ANOTHER ROUND OF ISOLD SHRA/TSRA POSSIBLE THIS
EVENING AS PRIMARY SFC FRONT ARRIVES. PLENTY OF DRY AIR REMAINS OVER
THE AREA WHICH MAY INHIBIT DEVELOPMENT. WENT FOR SHORT PERIOD OF
VCSH AT CMX WHICH IS IN BEST PROXIMITY TO A DISTURANCE TO THE NORTH
AND LIFT AHEAD OF A WARM FRONT...THEN SHARP DRYING/CLEARING
OVERNIGHT TONIGHT. WILL ALSO SEE GUSTY WEST WINDS IN WAKE OF THE
FRONT...STRONGEST AT THE MORE EXPOSED KCMX.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 422 PM EDT TUE MAY 14 2013
SOUTHERLY FLOW WAS INCREASING AHEAD OF A LOW PRESSURE SYSTEM MOVING
EAST THROUGH SOUTHERN CANADA. WINDS INCREASE TO 25 KTS TONIGHT INTO WED
BUT WILL BE LIMITED AS LOW LEVEL WARM AIR ADVECTION RESULTS IN
INCREASING STABILITY. WINDS ARE EXPECTED TO REMAIN BELOW
30KTS LATER THIS WEEK AND INTO THE WEEKEND. AFTER COOL AND WINTRY
WEATHER FOR THE SPRING SO FAR...SUMMERTIME WEATHER IS BECOMING MORE
COMMON. THUNDERSTORMS ARE POSSIBLE TONIGHT AND ENDING BY
EARLY WEDNESDAY. ANOTHER ROUND OF THUNDERSTORMS WILL BE POSSIBLE
WEST ON SATURDAY/SATURDAY NIGHT...AND ACROSS ALL OF LAKE SUPERIOR
SUNDAY THROUGH MONDAY MORNING.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FIRE WEATHER WATCH FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY
EVENING FOR MIZ002-004>006-009>014-084-085.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...VOSS
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
142 AM EDT TUE MAY 14 2013
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 351 PM EDT MON MAY 13 2013
TWO WAVES/DISTURBANCES WILL BE THE FOCUS FOR THE FORECAST...WITH
THE FIRST ONE AFFECTING THE AREA TONIGHT AND THE OTHER TOMORROW
AFTERNOON/EVENING.
LATEST WV IMAGERY AND RUC ANALYSIS SHOWS THE AREA UNDER RIDGING
ALOFT AS THE UPPER TROUGH THAT HAD BEEN AFFECTING THE AREA THIS
WEEKEND SHIFTING EAST ACROSS QUEBEC AND AN UPPER RIDGE OVER THE
WESTERN CONUS. THERE IS A DECENT AMOUNT OF MOISTURE ROUNDING THE
RIDGE WITH A 996MB LOW JUST TO THE WEST OF LAKE WINNIPEG. CLOSER TO
HOME...SKIES WERE CLEAR OVER MUCH OF UPPER MICHIGAN THIS
MORNING...BUT INCREASING MID-HIGH CLOUDS ARE SPREADING ACROSS THE
AREA THIS AFTERNOON. BAND OF RAIN IS STARTING TO MOVE INTO WESTERN
LAKE SUPERIOR AT THIS TIME AND IS ASSOCIATED WITH A THIN AREA OF
800-500MB MOISTURE AND 700MB F-GEN.
EXPECT THE BAND TO CONTINUE EAST-SOUTHEAST THIS EVENING AS THE
700MB F-GEN AND BROAD 850-700MB WARM AIR ADVECTION CONTINUE.
BUT...WITH THE 500MB SHORTWAVE AND ASSOCIATED HEIGHT FALLS SHIFTING
EAST THROUGH ONTARIO AND WELL NORTH OF THE AREA ALONG WITH BEING
UNDER THE WRONG AREA OF THE UPPER JET /RIGHT EXIT/ THE BETTER
FORCING ISN/T OVER THE AREA. PLUS...WITH THE DRY AIR IT WILL BE
RUNNING INTO...WONDERING IF THAT WILL LIMIT THE INTENSITY SOME.
WITH AS PERSISTENT AS IT HAS BEEN TODAY...DID BUMP UP POPS A
TOUCH TO GET MORE CHANCE/SCATTERED WORDING IN FOR THIS
EVENING...BUT BASED OFF THE LIMITED RAIN AMOUNTS SEEN UPSTREAM
/TRACE TO A COUPLE HUNDREDTHS/ DIDN/T WANT TO GO MUCH ABOVE THAT. AS
ADDITIONAL 850-700MB MOISTURE SLIDES SOUTHEAST ACROSS THE EASTERN
CWA TONIGHT...WOULD THINK THE PRECIPITATION CHANCES SHOULD INCREASE
SOME OVERNIGHT. THERE IS LITTLE OR NO INSTABILITY WITH THIS PASSING
WAA...AS MID LEVEL LAPSE RATES ARE ONLY AROUND 3-5 C/KM...SO WILL
KEEP THUNDER OUT OF THE FORECAST. WITH THE BETTER CONSISTENCY IN
THIS MOISTURE ARRIVING OVER THE EAST...DID BUMP UP VALUES TO HIGH
CHANCE POPS THERE.
EXPECT TO SEE A BRIEF REPRIEVE ON TUESDAY MORNING BEHIND THE INITIAL
AREA OF WAA TONIGHT. THIS WILL LIKELY PRODUCE SOME BREAKS OR
CLEARING OVER AT LEAST THE WEST HALF OF THE CWA DURING THE MORNING
HOURS BEFORE MID-HIGH CLOUDS STREAM BACK INTO THE AREA. THEN...THE
SHORTWAVE THAT IS CURRENTLY ENTERING THE PACIFIC NORTHWEST WILL BE
MOVING EAST-NORTHEAST ALONG THE US/CANADIAN BORDER AND BE NEAR LAKE
WINNIPEG BY 18Z TUESDAY. WARM AIR ADVECTION WILL AGAIN BE ON THE
INCREASE FROM WEST TO EAST DURING THE AFTERNOON. MOISTURE WILL ALSO
BE LIMITED AS IT MOVES THROUGH THE AREA DURING THE AFTERNOON. BEST
MOISTURE AND CLOSEST PROXIMITY TO THE SHORTWAVE WILL BE OVER THE
NORTHWEST HALF OF THE CWA...SO WILL HAVE HIGHEST POPS THEIR DURING
THE LATTER PART OF THE AFTERNOON. QPF/REFLECTIVITY FROM HIGH
RESOLUTION MODEL RUNS SEEM TO MATCH THIS IDEA AND LEADS TO GREATER
CONFIDENCE.
ELEVATED INSTABILITY IS MARGINAL ALONG/NORTH THE WARM FRONT...WITH
THE BEST INSTABILITY FARTHER SOUTHWEST AND AHEAD OF THE COLD
FRONT. THIS IS LARGELY DUE TO THE MID-LEVEL LAPSE RATES STRUGGLING
TO GET ABOVE 6C/KM. THUS...THUNDER POTENTIAL WILL BE SLIM THROUGH
THE AFTERNOON HOURS. IF ANY ELEVATED THUNDERSTORMS
DEVELOP...WOULDN/T EXPECT THEM TO BE TOO STRONG...AS EFFECTIVE SHEAR
VALUES WILL LIKELY BE BELOW 30KTS THROUGH 00Z ACROSS ALL BUT THE FAR
SOUTHWEST CWA.
AFTER A COOL WEEKEND...TEMPERATURES HAVE STARTED TO REBOUND TODAY
AND EXPECT IT TO CONTINUE ON TUESDAY. THE WARM AIR ADVECTING INTO
THE AREA ON TUESDAY ALONG WITH INCREASING SOUTHERLY FLOW SHOULD LEAD
TO HIGHS IN THE LOWER 70S OVER THE FAR WEST AND A GRADIENT TO THE
50S OVER THE EAST HALF.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 351 PM EDT MON MAY 13 2013
MUCH OF THIS PERIOD WILL BE MARKED BY THE PRESENCE OF A 70KT OR
GREATER 250MB JET OVER UPPER MICHIGAN AND/OR LAKE SUPERIOR...AT
LEAST FROM TUESDAY NIGHT THROUGH SATURDAY MORNING. THIS WILL KEEP
THE AREA IN A RELATIVELY BUSY WEATHER PATTERN...IN BETWEEN THE DOME
OF HOT AIR OVER MUCH OF THE WESTERN HALF OF THE NATION...AND COLDER
AIR RESIDING OVER CANADA.
WE WILL START OUT TUESDAY NIGHT WITH A STACKED 500MB TROUGH-SFC LOW
SET UP JUST NORTH OF CYRL IN WESTERN MANITOBA. A COLD FRONT WILL
EXTEND S FROM THE SFC LOW...THROUGH THE EASTERN THIRD OF MN TO A
SECONDARY SFC LOW/TRIPLE POINT THAT MAY BE DEVELOPING NEAR KDLH.
THE LOCATION OF THE WARM FRONT IS KEY...LIKELY SET UP FROM THE
ARROWHEAD OF MN DOWN AND NEAR THE WI BORDER OF UPPER MI AT 00Z
WEDNESDAY. AS IS TYPICAL...THESE SPLITTING SYSTEMS CAN DEVELOP AND
ROB US OF MOISTURE...AS CONVECTION POPS UP OVER WI. EXPECT
WAA...LIMITED FORCING WILL LIKELY PERSIST...WITH MUCH OF THE BEST
FORCING CLOSER TO THE MAIN SFC/500MB TROUGH ACROSS ONTARIO /WHERE AN
AVERAGE QUARTER OF AN INCH OR MORE OF RAIN IS EXPECTED/. WE LOOK TO
BE IN A PRETTY CAPPED ENVIRONMENT...WITH THE BEST CHANCE FOR ANY
STRONGER SHOWERS OR THUNDERSTORMS OVER SOUTH CENTRAL AND EASTERN
UPPER MI DURING THE LATE EVENING HOURS...AND EVEN THEN LIKELY
ELEVATED ABOVE THE DRY AIR. THE SOUTHERN LOW/COLD FRONT WILL BE OVER
EASTERN UPPER MI/LAKE SUPERIOR BY 09Z WEDNESDAY...AND EAST OF UPPER
MI BY 12Z.
COOLER/DRIER AIR WILL SWEEP IN FOR WEDNESDAY...WITH 850MB TEMPS
FALLING FROM A MAX 14-18C OVERNIGHT TO AN AVERAGE 7-8C DURING THE
DAY WEDNESDAY. PW VALUES FALL TO 0.37 TO 0.44IN...OR 60-70 PERCENT
OF NORMAL...WITH THE LOWEST VALUES AWAY FROM THE KEWEENAW PENINSULA
AND EXTREME S CENTRAL UPPER MI. EXPECT A MORE MODERATED AIRMASS FROM
MUNISING EASTWARD AS MORE MOIST AIR SLIDES IN NEAR THE SHORELINE. A
WORST CASE SCENARIO...WITH THE NAM MIXING UP TO 650-700MB DURING THE
AFTERNOON HOURS...DEW POINTS MIXING DOWN INTO THE UPPER 20S
/F/ WOULD RESULT IN AFTERNOON MIN RH VALUES OF 19-25 PERCENT FROM
JUST E OF IWD TO NORTHERN DELTA COUNTY...WITH GUSTS 25-30KTS. ON A
POSITIVE NOTE...THE LATEST MODEL RUNS ARE NOT QUITE AS STRONG WITH
THE WINDS. WILL NEED TO WAIT AND SEE IF THIS TREND HOLDS. IF
LIMITED...OR NO...PRECIPITATION FALLS TUESDAY NIGHT...FIRE CONCERNS
WILL BE ELEVATED.
BEHIND THE ELONGATED LOW SHIFTING EAST INTO QUEBEC WEDNESDAY
NIGHT...DRY WEATHER WILL REMAIN THROUGH FRIDAY MORNING...WITH COOL
WEST TO NORTHWEST FLOW LINGERING. EXPECT THE RIDGE OF HIGH PRESSURE
TO BE DIRECTLY OVERHEAD ON THURSDAY...WITH LIGHT WINDS AND LAKE
BREEZES EXPECTED.
OUR NEXT WEATHER MAKER WILL BE ORGANIZING ACROSS THE CENTRAL PLAINS
FRIDAY NIGHT THROUGH SATURDAY...BEFORE SHIFTING TOWARD MN AND IA
SATURDAY NIGHT. THE SFC LOW WILL SIT AND SPIN BEFORE FINALLY EXITING
NORTHEASTWARD ACROSS W LAKE SUPERIOR AROUND 06Z MONDAY AND SOUTHERN
ONTARIO DURING THE DAY MONDAY...AS THE 500MB TROUGH/LOW DIVES ACROSS
THE NORTHERN PLAINS SUNDAY INTO SUNDAY NIGHT. ADDED TS CHANCES
SATURDAY THROUGH MONDAY MORNING...BEFORE THE END TO THE BULK OF
MOISTURE. AT THIS POINT IT LOOKS LIKE THERE WILL BE A GOOD CHANCE OF
SOAKING RAIN OVER THE FAR W PORTIONS OF UPPER MI FRIDAY NIGHT
THROUGH SATURDAY...WITH ANOTHER ROUND POSSIBLE LATER SUNDAY INTO
MONDAY AS THE COLD FRONT SWINGS THROUGH.
OTHER THAN SUNDAY TIMING DIFFERENCES BETWEEN THE 12Z RUNS OF THE GFS
AND ECMWF...THE FCST MODELS ARE IN NORMAL TO SLIGHTLY ABOVE NORMAL
AGREEMENT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 139 AM EDT TUE MAY 14 2013
VFR CONDITIONS REMAIN THE RULE AT ALL THREE TAF SITES THROUGH THE
FORECAST PERIOD. CLOUD COVER AND RAIN SHOWERS HAVE ALL BUT EXITED
KIWD AREA AND WILL MOVE OUT OF KCMX BY 8Z...AND KSAW SHORTLY AFTER
THEN. WEAK RIDGING ALOFT BEHIND THE DISTURBANCE WILL REDUCE CLOUD
COVER UNTIL THE APPROACH OF THE NEXT SHORT WAVE BRINGS INCREASING MID
AND HIGH CLOUDS TO THE AREA IN THE LATE AFTERNOON/EVENING. AT THIS
TIME...BETTER MOISTURE AND LOW LEVEL FORCING TO BE FOUND SOUTH OF THE
AREA IN WI...WHILE BETTER DYNAMIC LIFT LOCATED NORTH OF THE
BORDER...LEAVING THE THREE TAF SITES IN BETWEEN. WITH NO STRONG
SIGNAL...WILL JUST MENTION VCSH AT KIWD AND KCMX AND WILL LEAVE OUT
OF KSAW FOR NOW. &&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 351 PM EDT MON MAY 13 2013
HIGH PRESSURE WILL DEPART THE AREA THIS EVENING. THIS WILL LEAD TO
INCREASING SOUTHERLY FLOW TONIGHT INTO TUESDAY AHEAD OF A LOW
PRESSURE SYSTEM MOVING EAST THROUGH SOUTHERN CANADA. AT THIS
POINT...THE INCREASING WARM AIR ABOVE THE SURFACE SHOULD LIMIT GUST
TO 20KTS IN MOST LOCATIONS FOR OVERNIGHT TONIGHT AND TUESDAY.
DISPITE A COUPLE OF SIGNIFICANT SYSTEMS PUSHING THROUGH THE AREA
TUESDAY-TUESDAY NIGHT...AND AGAIN THIS WEEKEND...WINDS ARE CURRENTLY
ANTICIPATED TO REMAIN BELOW 30KTS. IT IS THAT TIME OF YEAR
AGAIN...THERE WILL BE A ROUND OF THUNDERSTORMS POSSIBLE TUESDAY
AFTERNOON OVER WESTERN LAKE SUPERIOR...PUSHING EASTWARD OVERNIGHT
AND ENDING EARLY WEDNESDAY. ANOTHER ROUND OF THUNDERSTORMS WILL BE
POSSIBLE WEST ON SATURDAY/SATURDAY NIGHT...AND ACROSS ALL OF LAKE
SUPERIOR SUNDAY THROUGH MONDAY MORNING.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...KF
AVIATION...RJT
MARINE...SRF/KF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
126 PM CDT TUE MAY 14 2013
.UPDATE...
ISSUED AT 1241 PM CDT TUE MAY 14 2013
DECAYING CLOUDS AND SHOWERS NOW OVER WRN WI HAS GENERATED A STRONG
WARM FRONT ACROSS MN FROM ABOUT ABOUT DODGE CENTER...TO LE SEUR
AND UP TO ABOUT MORRIS...WHERE IT MEETS UP WITH A N-S ORIENTED
"COLD" FRONT THAT SITS JUST EAST OF FERGUS FALLS TO MARSHALL AT 1
PM. THIS WARM FRONT IS PROBABLY LEADING TO SOME COLD FEET FOR
FORECASTERS IN THE TWIN CITIES AND CENTRAL MN...WHERE AT 1 PM IT
WAS ONLY 81 AT MSP. HOWEVER...TO THOSE QUESTIONING 90S OCCURRING
IN THE TWIN CITIES...BE PATIENT...TEMPERATURES ON THE OTHER SIDE
OF THE WARM REALLY TAKE OFF. FOR INSTANCE...OLIVIA WENT FROM 81
TO 95 IN 90 MINUTES AND MANKATO WENT FROM 84 AT NOON TO 97 AT 1
PM. SO BE PATIENT...ALL IT WILL TAKE IS AN HOUR OR TWO IN THE WARM
SECTOR TO START PUSHING TEMPERATURES INTO THE MID 90S! STILL
CONFIDENT THAT THE RECORD OF 95 AT MSP IS VERY MUCH IN JEOPARDY
TODAY.
FINALLY...18Z AVIATION DISCUSSION ADDED BELOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 440 AM CDT TUE MAY 14 2013
THERE ARE MANY CONCERNS TODAY AS A LOW PRESSURE SYSTEM AND COLD
FRONT MOVE ACROSS THE FA DURING THE AFTERNOON AND EVENING. A SMALL
COMPLEX OF THUNDERSTORMS DID DEVELOP OVER NORTH DAKOTA OVERNIGHT AS
EXPECTED. THIS AREA OF PRECIPITATION WILL ADVANCE ACROSS NORTHERN
MN THIS MORNING. CONSENSUS FROM THE WRF MODELS WAS LITTLE
(SPRINKLES) OR NOTHING REACHING DOWN INTO CENTRAL MN OTHER THAN
SOME CLOUDS. BY LATE MORNING...THE LOW AND COLD FRONT SHOULD BE
INTO FAR WESTERN AREAS OF MN. SOUTH TO SOUTHWEST WINDS WILL INCREASE
AHEAD OF THE FRONT WHILE RATHER STRONG WEST/NORTHWEST WINDS OCCUR
IN THE WAKE OF THE FRONT. A LOW LEVEL THERMAL RIDGE WILL ADVANCE
NORTHEAST FROM THE CENTRAL PLAINS AND REACH INTO THE TWIN CITIES
BY LATE IN THE AFTERNOON. THE SHORT TERM MODELS REMAIN CONSISTENT
ON 23-26 DEG C AIR AT 850MB FROM THE TWIN CITIES ON SOUTHWEST INTO
NORTHERN IA RESPECTIVELY. HIGHS RECENTLY TO OUR WEST AND NORTHWEST
(CANADA) HAVE BEEN RUNNING REAL CLOSE TO 20 DEGREES ABOVE THESE
CONVERTED VALUES. THIS WOULD YIELD HIGHS FROM 93 TO 99 DEGREES.
AS A RESULT... OUR CURRENT FORECAST WAS RAISED A FEW DEGREES...
ESPECIALLY ACROSS SOUTH CENTRAL MN... WHERE THE RAP SOUNDINGS WERE
SHOWING HIGHS OF 100-103. THIS ALSO RESULTED IN A RECORD HIGH BEING
FORECAST FOR THE TWIN CITIES.
THE HEAT TODAY HAS LEAD TO THE ISSUANCE OF A HEAT ADVISORY FROM
THE TWIN CITIES ON SOUTH AND SOUTHWEST TO ALBERT LEA AND REDWOOD
FALLS. THIS IS A DRY HEAT BEING ACCOMPANIED BY 20 TO 25 MPH WINDS
DURING THE AFTERNOON... WHICH MAY LEAD TO DEHYDRATION ISSUES FOR
THOSE WORKING OUTSIDE. ANOTHER IMPORTANT ISSUE IS THAT THE TWIN
CITIES HAS ONLY BEEN IN THE 80S ONCE SO FAR THIS YEAR WITH 81
DEGREES ON APRIL 28TH. THIS BURST OF HEAT MAY LEAD TO HEALTH
ISSUES.
ANOTHER CONCERN TODAY IS THE POTENTIAL FOR WIND ADVISORY CRITERIA
BEING MET IN THE NORTHWEST CWA IN THE MID TO LATE AFTERNOON HOURS.
THE RAP LOW LEVEL WINDS IN THE 200-300 FOOT RANGE ARE FORECAST IN
THE UPPER 20 KNOT RANGE. THIS IS THE HIGHEST OF ALL THE GUIDANCE.
THE NAM WINDS WERE MORE IN THE 23-24 KNOT RANGE WHICH BLENDED WELL
WITH THE LAMP GUIDANCE. CRITERIA FOR A WIND ADVISORY HAS A BETTER
CHANCE OF BEGIN MET OVER NORTH DAKOTA. AT THIS POINT WE HELD OFF
ON ISSUING AN ADVISORY.
FINALLY...ALTHOUGH A STRONG CAP EXISTS IN THE 700-750MB RANGE
TODAY...THERE REMAINS SOME POTENTIAL FOR CONVECTION TO BREACH THE
CAP AND DEVELOP DURING THE LATE AFTERNOON/EVENING ALONG THE
FRONT... MAINLY TO THE EAST AND SOUTH OF THE TWIN CITIES. WE KEPT
THE SMALL CHANCES FOR THUNDERSTORMS AS IS. OUR LOCAL WRF WAS THE
MOST AGGRESSIVE WITH ACTIVITY DEVELOPING FROM JUST SOUTH OF THE
TWIN CITIES TO OMAHA AROUND 21Z...WHILE THE NMM WRF HAS SOME
STORMS JUST EAST OF US. MOST OF THE SOLUTIONS SHOW A HIGHER CHANCE
FOR STORMS OVER IA TONIGHT AS WELL AS IN NORTHEAST WI. GIVEN THE
SHEAR FORECAST...STORMS THAT DO DEVELOP COULD BECOME SEVERE WITH
LARGE HAIL AND DAMAGING WINDS... ESPECIALLY WITH THE INVERTED V
SOUNDING. NAM DOWNDRAFT CAPE VALUES ARE ON THE ORDER OF 1000 J/KG
OVER WEST CENTRAL WI AND SE MN LATE THIS AFTERNOON AND EVENING.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 415 AM CDT TUE MAY 14 2013
WEDNESDAY THROUGH MONDAY...QUIET AND SEASONABLE WEATHER WILL GIVE
WAY TO A WETTER PATTERN AT THE END OF THE PERIOD. SEVERE WEATHER IS
ALSO POSSIBLE FOR THE WEEKEND. EARLY MORNING NORTHERN HEMISPHERIC IR
IMAGERY TOGETHER WITH THE ECMWF 250MB HEIGHTS AND WINDS IDENTIFIED
ZONAL FLOW ACROSS THE WESTERN CONUS...WITH A LOW AMPLITUDE PATTERN
ACROSS THE PACIFIC. FOR WEDNESDAY AND THURSDAY THIS ZONAL FLOW WILL
SET UP ACROSS INTERNATIONAL BORDER...WITH NEGATIVE VORTICITY
ADVECTION AND WEAK SUBSIDENCE ACROSS THE UPPER MIDWEST. THIS WILL
RESULT IN TWO DRY DAYS WITH LIGHT WINDS AND TEMPERATURES 5 TO 10
DEGREES ABOVE THE SEASONAL AVERAGE FOR MID MAY.
BY THURSDAY NIGHT THE AFOREMENTIONED LOW AMPLITUDE JET ACROSS THE
PACIFIC WILL BEGIN TO DIG ACROSS THE WESTERN US...WITH A BROAD AREA
OF LEE SIDE TROUGHING ALONG THE EASTERN SPINE OF THE ROCKIES. THIS
WILL INDUCE SOUTHERLY FLOW WITH GULF MOISTURE TRANSPORT ACROSS THE
CENTRAL CONUS...AND GRADUALLY BUILD AN UPPER LEVEL RIDGE THURSDAY
NIGHT INTO FRIDAY. MEANWHILE THE COLD FRONT THAT WILL HAVE PASSED
THROUGH THE AREA ON TUESDAY AND STALL OUT ACROSS SOUTHERN IOWA WILL
LIFT NORTHWARD AS A WARM FRONT. LOW LEVEL THETA_E ADVECTION AS SEEN
IN THE H925-850 LAYER SHOULD PROMOTE THUNDERSTORM DEVELOPMENT ALONG
THE WARM FRONT...WHILE THE UPPER LEVEL ANTICYCLONIC FLOW ALOFT
ALLOWS EVACUATES THE OUTFLOW FROM THESES STORMS AND ALLOWS THEM TO
PERSIST. DIFFICULT TO QUANTIFY THE CONVECTIVE POTENTIAL SINCE THE
LOW LEVEL MOISTURE HAS BEEN UNRELIABLE LATELY. HOWEVER...THE
SYNOPTIC SETUP WITH GULF MOISTURE ADVECTION INCREASES CONFIDENCE
THAT THESE MOISTURE DEPENDENT VARIABLES...A.K.A. CAPE...ARE
REASONABLY REPRESENTED. DEEP LAYER SHEAR PROFILES VARY DEPENDING ON
THE TIMING AND PLACEMENT OF THE WARM FRONT...BUT BOTH THE 14.12 GFS
AND ECMWF ARE IN GOOD AGREEMENT AND LIFT THE FRONT THROUGH THE CWA
ON FRIDAY. MEANWHILE THE UPPER LEVEL JET WILL CONTINUE TO CARVE OUT
A TROUGH OVER THE FOUR CORNERS REGION. THE GFS...GEM...AND ECMWF ALL
DEVELOP A SURFACE LOW AND TRACK IT ACROSS THE UPPER MIDWEST FOR THE
WEEKEND...BRINGING CONTINUED CHANCES FOR PRECIP. THE RUN TOTAL
PRECIP FROM THE GFS AND ECMWF INDICATE THAT OVER 3 INCHES OF RAIN
ARE POSSIBLE. WITH THIS PROLONGED PERIOD OF PRECIP. IN
SUMMATION...EXPECT AN MCS TO DEVELOP THURSDAY NIGHT AND MOVE ACROSS
THE REGION FRIDAY AS THE WARM FRONT LIFTS NORTHWARD. THEN WILL SEE
CONTINUES CHANCES FOR THUNDERSTORMS SATURDAY AND SUNDAY AS THE UPPER
LEVEL DYNAMICS BECOME MORE FAVORABLE FOR ASCENT. SEVERE WEATHER
REMAINS POSSIBLE...BUT CONFIDENCE IN THE EXACT PLACEMENT OF THE
MESOSCALE FEATURES IS LOW AT THIS TIME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1241 PM CDT TUE MAY 14 2013
WARM FRONT MENTIONED IN UPDATE LEADING TO BIGGEST AVIATION ISSUE
THIS PERIOD...WIND DIRECTIONS. NORTH OF THE WARM FRONT...WINDS
HAVE BACKED CONSIDERABLY MORE THAN EXPECTED...WITH STC/MSP/RNH/EAU
ALL EXPERIENCING ESE WINDS. COLD FRONT IN THE AREA OF AXN RIGHT
NOW AND 12Z TAFS STILL HAD FROPA AND WIND SHIFT TIMED WELL...SO
MADE FEW CHANGES TO THE TIMING OF THE FROPA WITH THESE TAFS. WARM
SECTOR JUST TO HOT/DRY TO THINK THERE IS EVEN A REMOTE CHANCE FOR
A TSRA...SO DID NOT CONTINUE MENTION OF TS AT EAU. REST OF TAF
LOOKS GOOD...WITH WEAKER NW WINDS AND MAINLY CLEAR SKIES EXPECTED
FROM TONIGHT THROUGH WEDNESDAY.
KMSP...OUTSIDE OF TWEAKING WIND DIRECTION TO BE MORE SE AT THE
BEGINNING...FEW CHANGES WERE NEEDED FOR THE TAF. EXPECT A FAIRLY
RAPID VEERING OF WINDS THIS AFTERNOON AS THE COLD FRONT MOVES
THROUGH BETWEEN 21 AND 22Z. DURING THIS HOUR WIND SPEEDS WILL
LIKELY BACK OFF SOME..BUT EXPECT 270-300 WINDS TO QUICKLY PICK UP
IN STRENGTH AND GUSTINESS IN ITS WAKE. LOOKS LIKE THE WIND SHIFT
SHOULD COME IN JUST BEFORE THE EVENING PUSH STARTS...SO SHOULD BE
ABLE TO GET RUNWAYS TURNED AROUND BEFORE PEAK VOLUME HITS.
/OUTLOOK FOR KMSP/
THU...VFR. LGT AND VRBL WINDS.
FRI...VFR WITH MVFR/-TSRA LIKELY. SE WINDS 10 KTS.
SAT...MVFR OR LOWER WITH -TSRA LIKELY. SE WINDS 5-10 KTS.
&&
.FIRE WEATHER...
ISSUED AT 440 AM CDT TUE MAY 14 2013
A RED FLAG WARNING NOW COVERS ALL OF OUR MN COUNTIES FOR THIS
AFTERNOON AND EARLY EVENING. A DRY SURGE OF HEAT WILL OCCUR TODAY
WITH AFTERNOON HUMIDITY VALUES LOWERING TO A FEW PERCENT ABOVE AND
BELOW 20. THE VERY LOW HUMIDITY COUPLED WITH SOUTHWEST TO WEST
WINDS FROM 20 TO 25 MPH ...WITH GUSTS TO 35 MPH... COULD LEAD TO
DANGEROUS WILDFIRE CONDITIONS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR MNZ041>045-
047>070-073>078-082>085-091>093.
HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR MNZ059>063-065>070-
073>077-082>085-091>093.
WI...NONE.
&&
$$
UPDATE...MPG
SHORT TERM...RAH
LONG TERM...JRB
AVIATION...MPG
FIRE WEATHER...RAH
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
633 AM CDT TUE MAY 14 2013
.FIRE WEATHER...
ISSUED AT 440 AM CDT TUE MAY 14 2013
A RED FLAG WARNING NOW COVERS ALL OF OUR MN COUNTIES FOR THIS
AFTERNOON AND EARLY EVENING. A DRY SURGE OF HEAT WILL OCCUR TODAY
WITH AFTERNOON HUMIDITY VALUES LOWERING TO A FEW PERCENT ABOVE AND
BELOW 20. THE VERY LOW HUMIDITY COUPLED WITH SOUTHWEST TO WEST
WINDS FROM 20 TO 25 MPH ...WITH GUSTS TO 35 MPH... COULD LEAD TO
DANGEROUS WILDFIRE CONDITIONS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 440 AM CDT TUE MAY 14 2013
THERE ARE MANY CONCERNS TODAY AS A LOW PRESSURE SYSTEM AND COLD
FRONT MOVE ACROSS THE FA DURING THE AFTERNOON AND EVENING. A SMALL
COMPLEX OF THUNDERSTORMS DID DEVELOP OVER NORTH DAKOTA OVERNIGHT AS
EXPECTED. THIS AREA OF PRECIPITATION WILL ADVANCE ACROSS NORTHERN
MN THIS MORNING. CONSENSUS FROM THE WRF MODELS WAS LITTLE
(SPRINKLES) OR NOTHING REACHING DOWN INTO CENTRAL MN OTHER THAN
SOME CLOUDS. BY LATE MORNING...THE LOW AND COLD FRONT SHOULD BE
INTO FAR WESTERN AREAS OF MN. SOUTH TO SOUTHWEST WINDS WILL INCREASE
AHEAD OF THE FRONT WHILE RATHER STRONG WEST/NORTHWEST WINDS OCCUR
IN THE WAKE OF THE FRONT. A LOW LEVEL THERMAL RIDGE WILL ADVANCE
NORTHEAST FROM THE CENTRAL PLAINS AND REACH INTO THE TWIN CITIES
BY LATE IN THE AFTERNOON. THE SHORT TERM MODELS REMAIN CONSISTENT
ON 23-26 DEG C AIR AT 850MB FROM THE TWIN CITIES ON SOUTHWEST INTO
NORTHERN IA RESPECTIVELY. HIGHS RECENTLY TO OUR WEST AND NORTHWEST
(CANADA) HAVE BEEN RUNNING REAL CLOSE TO 20 DEGREES ABOVE THESE
CONVERTED VALUES. THIS WOULD YIELD HIGHS FROM 93 TO 99 DEGREES.
AS A RESULT... OUR CURRENT FORECAST WAS RAISED A FEW DEGREES...
ESPECIALLY ACROSS SOUTH CENTRAL MN... WHERE THE RAP SOUNDINGS WERE
SHOWING HIGHS OF 100-103. THIS ALSO RESULTED IN A RECORD HIGH BEING
FORECAST FOR THE TWIN CITIES.
THE HEAT TODAY HAS LEAD TO THE ISSUANCE OF A HEAT ADVISORY FROM
THE TWIN CITIES ON SOUTH AND SOUTHWEST TO ALBERT LEA AND REDWOOD
FALLS. THIS IS A DRY HEAT BEING ACCOMPANIED BY 20 TO 25 MPH WINDS
DURING THE AFTERNOON... WHICH MAY LEAD TO DEHYDRATION ISSUES FOR
THOSE WORKING OUTSIDE. ANOTHER IMPORTANT ISSUE IS THAT THE TWIN
CITIES HAS ONLY BEEN IN THE 80S ONCE SO FAR THIS YEAR WITH 81
DEGREES ON APRIL 28TH. THIS BURST OF HEAT MAY LEAD TO HEALTH
ISSUES.
ANOTHER CONCERN TODAY IS THE POTENTIAL FOR WIND ADVISORY CRITERIA
BEING MET IN THE NORTHWEST CWA IN THE MID TO LATE AFTERNOON HOURS.
THE RAP LOW LEVEL WINDS IN THE 200-300 FOOT RANGE ARE FORECAST IN
THE UPPER 20 KNOT RANGE. THIS IS THE HIGHEST OF ALL THE GUIDANCE.
THE NAM WINDS WERE MORE IN THE 23-24 KNOT RANGE WHICH BLENDED WELL
WITH THE LAMP GUIDANCE. CRITERIA FOR A WIND ADVISORY HAS A BETTER
CHANCE OF BEGIN MET OVER NORTH DAKOTA. AT THIS POINT WE HELD OFF
ON ISSUING AN ADVISORY.
FINALLY...ALTHOUGH A STRONG CAP EXISTS IN THE 700-750MB RANGE
TODAY...THERE REMAINS SOME POTENTIAL FOR CONVECTION TO BREACH THE
CAP AND DEVELOP DURING THE LATE AFTERNOON/EVENING ALONG THE
FRONT... MAINLY TO THE EAST AND SOUTH OF THE TWIN CITIES. WE KEPT
THE SMALL CHANCES FOR THUNDERSTORMS AS IS. OUR LOCAL WRF WAS THE
MOST AGGRESSIVE WITH ACTIVITY DEVELOPING FROM JUST SOUTH OF THE
TWIN CITIES TO OMAHA AROUND 21Z...WHILE THE NMM WRF HAS SOME
STORMS JUST EAST OF US. MOST OF THE SOLUTIONS SHOW A HIGHER CHANCE
FOR STORMS OVER IA TONIGHT AS WELL AS IN NORTHEAST WI. GIVEN THE
SHEAR FORECAST...STORMS THAT DO DEVELOP COULD BECOME SEVERE WITH
LARGE HAIL AND DAMAGING WINDS... ESPECIALLY WITH THE INVERTED V
SOUNDING. NAM DOWNDRAFT CAPE VALUES ARE ON THE ORDER OF 1000 J/KG
OVER WEST CENTRAL WI AND SE MN LATE THIS AFTERNOON AND EVENING.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 415 AM CDT TUE MAY 14 2013
WEDNESDAY THROUGH MONDAY...QUIET AND SEASONABLE WEATHER WILL GIVE
WAY TO A WETTER PATTERN AT THE END OF THE PERIOD. SEVERE WEATHER IS
ALSO POSSIBLE FOR THE WEEKEND. EARLY MORNING NORTHERN HEMISPHERIC IR
IMAGERY TOGETHER WITH THE ECMWF 250MB HEIGHTS AND WINDS IDENTIFIED
ZONAL FLOW ACROSS THE WESTERN CONUS...WITH A LOW AMPLITUDE PATTERN
ACROSS THE PACIFIC. FOR WEDNESDAY AND THURSDAY THIS ZONAL FLOW WILL
SET UP ACROSS INTERNATIONAL BORDER...WITH NEGATIVE VORTICITY
ADVECTION AND WEAK SUBSIDENCE ACROSS THE UPPER MIDWEST. THIS WILL
RESULT IN TWO DRY DAYS WITH LIGHT WINDS AND TEMPERATURES 5 TO 10
DEGREES ABOVE THE SEASONAL AVERAGE FOR MID MAY.
BY THURSDAY NIGHT THE AFOREMENTIONED LOW AMPLITUDE JET ACROSS THE
PACIFIC WILL BEGIN TO DIG ACROSS THE WESTERN US...WITH A BROAD AREA
OF LEE SIDE TROUGHING ALONG THE EASTERN SPINE OF THE ROCKIES. THIS
WILL INDUCE SOUTHERLY FLOW WITH GULF MOISTURE TRANSPORT ACROSS THE
CENTRAL CONUS...AND GRADUALLY BUILD AN UPPER LEVEL RIDGE THURSDAY
NIGHT INTO FRIDAY. MEANWHILE THE COLD FRONT THAT WILL HAVE PASSED
THROUGH THE AREA ON TUESDAY AND STALL OUT ACROSS SOUTHERN IOWA WILL
LIFT NORTHWARD AS A WARM FRONT. LOW LEVEL THETA_E ADVECTION AS SEEN
IN THE H925-850 LAYER SHOULD PROMOTE THUNDERSTORM DEVELOPMENT ALONG
THE WARM FRONT...WHILE THE UPPER LEVEL ANTICYCLONIC FLOW ALOFT
ALLOWS EVACUATES THE OUTFLOW FROM THESES STORMS AND ALLOWS THEM TO
PERSIST. DIFFICULT TO QUANTIFY THE CONVECTIVE POTENTIAL SINCE THE
LOW LEVEL MOISTURE HAS BEEN UNRELIABLE LATELY. HOWEVER...THE
SYNOPTIC SETUP WITH GULF MOISTURE ADVECTION INCREASES CONFIDENCE
THAT THESE MOISTURE DEPENDENT VARIABLES...A.K.A. CAPE...ARE
REASONABLY REPRESENTED. DEEP LAYER SHEAR PROFILES VARY DEPENDING ON
THE TIMING AND PLACEMENT OF THE WARM FRONT...BUT BOTH THE 14.12 GFS
AND ECMWF ARE IN GOOD AGREEMENT AND LIFT THE FRONT THROUGH THE CWA
ON FRIDAY. MEANWHILE THE UPPER LEVEL JET WILL CONTINUE TO CARVE OUT
A TROUGH OVER THE FOUR CORNERS REGION. THE GFS...GEM...AND ECMWF ALL
DEVELOP A SURFACE LOW AND TRACK IT ACROSS THE UPPER MIDWEST FOR THE
WEEKEND...BRINGING CONTINUED CHANCES FOR PRECIP. THE RUN TOTAL
PRECIP FROM THE GFS AND ECMWF INDICATE THAT OVER 3 INCHES OF RAIN
ARE POSSIBLE. WITH THIS PROLONGED PERIOD OF PRECIP. IN
SUMMATION...EXPECT AN MCS TO DEVELOP THURSDAY NIGHT AND MOVE ACROSS
THE REGION FRIDAY AS THE WARM FRONT LIFTS NORTHWARD. THEN WILL SEE
CONTINUES CHANCES FOR THUNDERSTORMS SATURDAY AND SUNDAY AS THE UPPER
LEVEL DYNAMICS BECOME MORE FAVORABLE FOR ASCENT. SEVERE WEATHER
REMAINS POSSIBLE...BUT CONFIDENCE IN THE EXACT PLACEMENT OF THE
MESOSCALE FEATURES IS LOW AT THIS TIME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 548 AM CDT TUE MAY 14 2013
A COLD FRONT ACROSS THE EASTERN DAKOTAS WILL MOVE INTO WESTERN MN
BY 15Z. THE FRONT SHOULD REACH THE TWIN CITIES AROUND 22Z AND PASS
KEAU BY 15/02Z. SOME STORMS HAVE DEVELOPED ALONG THE FRONT THIS
MORNING AND WILL BE PASSING THROUGH KAXN THROUGH 15Z. GUSTY WINDS
TO 40 KNOTS MAY OCCUR WITH THESE STORMS. THE ACTIVITY IS EXPECTED
TO WANE DURING THE MORNING AS A MID LEVEL CAP DEVELOPS. THIS
SHOULD HOLD OFF CONVECTION OVER EASTERN AREAS FOR MUCH OF THE
AFTERNOON... BUT BY 22Z OR SO SEVERAL WRF MODELS ARE HINTING AT
STORMS DEVELOPING JUST SOUTH AND EAST OF KMSP. THE SITE WITH THE
GREATEST RISK FOR SEEING A STORM IS KEAU AND A PROB GROUP FOR TSRA
REMAINS. ANOTHER CONCERN TODAY IS THE WIND. THE PREVIOUS TAF
FORECASTS HAD THIS HANDLED WELL AND LITTLE CHANGE WAS MADE.
INITIALLY S TO SW WINDS WILL INCREASE AHEAD OF THE FRONT TO 15
KNOTS WITH GUSTS INTO THE 20-25 KNOT RANGE AND THEN BECOME W TO NW
WITH FROPA NEAR 20 KNOTS WITH GUSTS TO NEAR 30 KNOTS. THE WIND
WILL THEN DIMINISH DURING THE EVENING.
KMSP...SOUTH WINDS (180-200) INCREASING TO 12 KNOTS WITH GUSTS 18
KNOTS BY 16Z THEN BECOMING MORE SW FOR THE AFTERNOON (210-230)
WITH A FURTHER INCREASE TO 15-20 KNOTS. GUSTS AROUND 25 KNOTS WILL
ALSO OCCUR. WEST WINDS AROUND 20 KNOTS FOR THE LATE
AFTERNOON/EVENING PUSH. GUSTS WILL CONTINUE. THERE IS ALSO A
THREAT FOR STORMS TO DEVELOP...BUT AT THIS TIME THEY ARE EXPECTED
TO BE EAST AND SOUTH OF THE AIRFIELD. DIMINISHING WIND AFTER 15/03Z.
/OUTLOOK FOR KMSP/
WED...VFR. NW WINDS 10 KTS.
THU...VFR. LGT AND VRBL WINDS.
FRI...VFR WITH MVFR/-TSRA POSSIBLE. SE WINDS 10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...RED FLAG WARNING FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR
MNZ041>045-047>070-073>078-082>085-091>093.
HEAT ADVISORY FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR
MNZ059>063-065>070-073>077-082>085-091>093.
WI...NONE.
&&
$$
FIRE WEATHER...RAH
SHORT TERM...RAH
LONG TERM...JRB
AVIATION...RAH
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
443 AM CDT TUE MAY 14 2013
.FIRE WEATHER...
ISSUED AT 440 AM CDT TUE MAY 14 2013
A RED FLAG WARNING NOW COVERS ALL OF OUR MN COUNTIES FOR THIS
AFTERNOON AND EARLY EVENING. A DRY SURGE OF HEAT WILL OCCUR TODAY
WITH AFTERNOON HUMIDITY VALUES LOWERING TO A FEW PERCENT ABOVE AND
BELOW 20. THE VERY LOW HUMIDITY COUPLED WITH SOUTHWEST TO WEST
WINDS FROM 20 TO 25 MPH ...WITH GUSTS TO 35 MPH... COULD LEAD TO
DANGEROUS WILDFIRE CONDITIONS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 440 AM CDT TUE MAY 14 2013
THERE ARE MANY CONCERNS TODAY AS A LOW PRESSURE SYSTEM AND COLD
FRONT MOVE ACROSS THE FA DURING THE AFTERNOON AND EVENING. A SMALL
COMPLEX OF THUNDERSTORMS DID DEVELOP OVER NORTH DAKOTA OVERNIGHT AS
EXPECTED. THIS AREA OF PRECIPITATION WILL ADVANCE ACROSS NORTHERN
MN THIS MORNING. CONSENSUS FROM THE WRF MODELS WAS LITTLE
(SPRINKLES) OR NOTHING REACHING DOWN INTO CENTRAL MN OTHER THAN
SOME CLOUDS. BY LATE MORNING...THE LOW AND COLD FRONT SHOULD BE
INTO FAR WESTERN AREAS OF MN. SOUTH TO SOUTHWEST WINDS WILL INCREASE
AHEAD OF THE FRONT WHILE RATHER STRONG WEST/NORTHWEST WINDS OCCUR
IN THE WAKE OF THE FRONT. A LOW LEVEL THERMAL RIDGE WILL ADVANCE
NORTHEAST FROM THE CENTRAL PLAINS AND REACH INTO THE TWIN CITIES
BY LATE IN THE AFTERNOON. THE SHORT TERM MODELS REMAIN CONSISTENT
ON 23-26 DEG C AIR AT 850MB FROM THE TWIN CITIES ON SOUTHWEST INTO
NORTHERN IA RESPECTIVELY. HIGHS RECENTLY TO OUR WEST AND NORTHWEST
(CANADA) HAVE BEEN RUNNING REAL CLOSE TO 20 DEGREES ABOVE THESE
CONVERTED VALUES. THIS WOULD YIELD HIGHS FROM 93 TO 99 DEGREES.
AS A RESULT... OUR CURRENT FORECAST WAS RAISED A FEW DEGREES...
ESPECIALLY ACROSS SOUTH CENTRAL MN... WHERE THE RAP SOUNDINGS WERE
SHOWING HIGHS OF 100-103. THIS ALSO RESULTED IN A RECORD HIGH BEING
FORECAST FOR THE TWIN CITIES.
THE HEAT TODAY HAS LEAD TO THE ISSUANCE OF A HEAT ADVISORY FROM
THE TWIN CITIES ON SOUTH AND SOUTHWEST TO ALBERT LEA AND REDWOOD
FALLS. THIS IS A DRY HEAT BEING ACCOMPANIED BY 20 TO 25 MPH WINDS
DURING THE AFTERNOON... WHICH MAY LEAD TO DEHYDRATION ISSUES FOR
THOSE WORKING OUTSIDE. ANOTHER IMPORTANT ISSUE IS THAT THE TWIN
CITIES HAS ONLY BEEN IN THE 80S ONCE SO FAR THIS YEAR WITH 81
DEGREES ON APRIL 28TH. THIS BURST OF HEAT MAY LEAD TO HEALTH
ISSUES.
ANOTHER CONCERN TODAY IS THE POTENTIAL FOR WIND ADVISORY CRITERIA
BEING MET IN THE NORTHWEST CWA IN THE MID TO LATE AFTERNOON HOURS.
THE RAP LOW LEVEL WINDS IN THE 200-300 FOOT RANGE ARE FORECAST IN
THE UPPER 20 KNOT RANGE. THIS IS THE HIGHEST OF ALL THE GUIDANCE.
THE NAM WINDS WERE MORE IN THE 23-24 KNOT RANGE WHICH BLENDED WELL
WITH THE LAMP GUIDANCE. CRITERIA FOR A WIND ADVISORY HAS A BETTER
CHANCE OF BEGIN MET OVER NORTH DAKOTA. AT THIS POINT WE HELD OFF
ON ISSUING AN ADVISORY.
FINALLY...ALTHOUGH A STRONG CAP EXISTS IN THE 700-750MB RANGE
TODAY...THERE REMAINS SOME POTENTIAL FOR CONVECTION TO BREACH THE
CAP AND DEVELOP DURING THE LATE AFTERNOON/EVENING ALONG THE
FRONT... MAINLY TO THE EAST AND SOUTH OF THE TWIN CITIES. WE KEPT
THE SMALL CHANCES FOR THUNDERSTORMS AS IS. OUR LOCAL WRF WAS THE
MOST AGGRESSIVE WITH ACTIVITY DEVELOPING FROM JUST SOUTH OF THE
TWIN CITIES TO OMAHA AROUND 21Z...WHILE THE NMM WRF HAS SOME
STORMS JUST EAST OF US. MOST OF THE SOLUTIONS SHOW A HIGHER CHANCE
FOR STORMS OVER IA TONIGHT AS WELL AS IN NORTHEAST WI. GIVEN THE
SHEAR FORECAST...STORMS THAT DO DEVELOP COULD BECOME SEVERE WITH
LARGE HAIL AND DAMAGING WINDS... ESPECIALLY WITH THE INVERTED V
SOUNDING. NAM DOWNDRAFT CAPE VALUES ARE ON THE ORDER OF 1000 J/KG
OVER WEST CENTRAL WI AND SE MN LATE THIS AFTERNOON AND EVENING.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 415 AM CDT TUE MAY 14 2013
WEDNESDAY THROUGH MONDAY...QUIET AND SEASONABLE WEATHER WILL GIVE
WAY TO A WETTER PATTERN AT THE END OF THE PERIOD. SEVERE WEATHER IS
ALSO POSSIBLE FOR THE WEEKEND. EARLY MORNING NORTHERN HEMISPHERIC IR
IMAGERY TOGETHER WITH THE ECMWF 250MB HEIGHTS AND WINDS IDENTIFIED
ZONAL FLOW ACROSS THE WESTERN CONUS...WITH A LOW AMPLITUDE PATTERN
ACROSS THE PACIFIC. FOR WEDNESDAY AND THURSDAY THIS ZONAL FLOW WILL
SET UP ACROSS INTERNATIONAL BORDER...WITH NEGATIVE VORTICITY
ADVECTION AND WEAK SUBSIDENCE ACROSS THE UPPER MIDWEST. THIS WILL
RESULT IN TWO DRY DAYS WITH LIGHT WINDS AND TEMPERATURES 5 TO 10
DEGREES ABOVE THE SEASONAL AVERAGE FOR MID MAY.
BY THURSDAY NIGHT THE AFOREMENTIONED LOW AMPLITUDE JET ACROSS THE
PACIFIC WILL BEGIN TO DIG ACROSS THE WESTERN US...WITH A BROAD AREA
OF LEE SIDE TROUGHING ALONG THE EASTERN SPINE OF THE ROCKIES. THIS
WILL INDUCE SOUTHERLY FLOW WITH GULF MOISTURE TRANSPORT ACROSS THE
CENTRAL CONUS...AND GRADUALLY BUILD AN UPPER LEVEL RIDGE THURSDAY
NIGHT INTO FRIDAY. MEANWHILE THE COLD FRONT THAT WILL HAVE PASSED
THROUGH THE AREA ON TUESDAY AND STALL OUT ACROSS SOUTHERN IOWA WILL
LIFT NORTHWARD AS A WARM FRONT. LOW LEVEL THETA_E ADVECTION AS SEEN
IN THE H925-850 LAYER SHOULD PROMOTE THUNDERSTORM DEVELOPMENT ALONG
THE WARM FRONT...WHILE THE UPPER LEVEL ANTICYCLONIC FLOW ALOFT
ALLOWS EVACUATES THE OUTFLOW FROM THESES STORMS AND ALLOWS THEM TO
PERSIST. DIFFICULT TO QUANTIFY THE CONVECTIVE POTENTIAL SINCE THE
LOW LEVEL MOISTURE HAS BEEN UNRELIABLE LATELY. HOWEVER...THE
SYNOPTIC SETUP WITH GULF MOISTURE ADVECTION INCREASES CONFIDENCE
THAT THESE MOISTURE DEPENDENT VARIABLES...A.K.A. CAPE...ARE
REASONABLY REPRESENTED. DEEP LAYER SHEAR PROFILES VARY DEPENDING ON
THE TIMING AND PLACEMENT OF THE WARM FRONT...BUT BOTH THE 14.12 GFS
AND ECMWF ARE IN GOOD AGREEMENT AND LIFT THE FRONT THROUGH THE CWA
ON FRIDAY. MEANWHILE THE UPPER LEVEL JET WILL CONTINUE TO CARVE OUT
A TROUGH OVER THE FOUR CORNERS REGION. THE GFS...GEM...AND ECMWF ALL
DEVELOP A SURFACE LOW AND TRACK IT ACROSS THE UPPER MIDWEST FOR THE
WEEKEND...BRINGING CONTINUED CHANCES FOR PRECIP. THE RUN TOTAL
PRECIP FROM THE GFS AND ECMWF INDICATE THAT OVER 3 INCHES OF RAIN
ARE POSSIBLE. WITH THIS PROLONGED PERIOD OF PRECIP. IN
SUMMATION...EXPECT AN MCS TO DEVELOP THURSDAY NIGHT AND MOVE ACROSS
THE REGION FRIDAY AS THE WARM FRONT LIFTS NORTHWARD. THEN WILL SEE
CONTINUES CHANCES FOR THUNDERSTORMS SATURDAY AND SUNDAY AS THE UPPER
LEVEL DYNAMICS BECOME MORE FAVORABLE FOR ASCENT. SEVERE WEATHER
REMAINS POSSIBLE...BUT CONFIDENCE IN THE EXACT PLACEMENT OF THE
MESOSCALE FEATURES IS LOW AT THIS TIME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1201 AM CDT TUE MAY 14 2013
VFR CONDITIONS THROUGH THE TAF PERIOD WITH JUST SOME HIGH CLOUDS
POSSIBLE. WIND WILL BE THE BIGGEST AVIATION WEATHER CONCERN
TOMORROW. WE SHOULD SEE PLENTY OF GUSTS BETWEEN 20-30 KTS IN MN BY
THE LATE MORNING OUT OF THE S-SW. WIND WILL FOLLOW IN WI 2-3 HOURS
LATER. EXPECT GUSTS NEAR OR OVER 30 KTS IN MANY LOCATIONS BY THE
AFTERNOON. NO REAL CONCERN WITH SHOWERS AND THUNDERSTORMS OUTSIDE
OF FAR EASTERN MN AND WESTERN WI TOMORROW AFTERNOON AND EVENING.
INCLUDE VCTS IN THE FORECAST FOR KEAU...BUT CONFIDENCE IN STORM
DEVELOPMENT AND COVERAGE IS STILL A BIG QUESTION MARK.
KMSP...
NO CONCERNS WITH THE CEILINGS OR VISIBILITY OVER THE NEXT 30
HOURS. THERE IS A SLIM CHANCE FOR A SHOWER OR THUNDERSTORM
TOMORROW AFTERNOON...BUT EVEN IF WE WERE CONFIDENT IN
DEVELOPMENT...THE COVERAGE LOOKS BETTER TO THE EAST AND IT SHOULD
EVEN BE ISOLATED WHERE IT DOES OCCUR. WINDS WILL BE STRONG OUT OF
THE S-SW BY THE AFTERNOON AND SLOWLY VEER AND REMAIN STRONG
THROUGH THE EVENING PUSH.
/OUTLOOK FOR KMSP/
WED...VFR. NW WINDS 10 KTS.
THU...VFR. WINDS W 5 KTS.
FRI...MVFR POSSIBLE WITH CHC -TSRA. WINDS SE 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...RED FLAG WARNING FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR
MNZ041>045-047>070-073>078-082>085-091>093.
HEAT ADVISORY FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR
MNZ059>063-065>070-073>077-082>085-091>093.
WI...NONE.
&&
$$
FIRE WEATHER...RAH
SHORT TERM...RAH
LONG TERM...JRB
AVIATION...CLF
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
845 PM MDT Wed May 15 2013
.DISCUSSION...
Update forthcoming. Have made some adjustments to the pop and
weather grids for the overnight period. Both the RUC and HRRR
analysis continue to show shower activity moving into southwest
Montana overnight as southwest flow aloft ahead of a west coast
upper trof maintains a moist and unstable feed into the state.
Increasing cloud cover should help keep temperatures a bit warmer
than last night`s readings and will leave them alone. Emanuel
&&
.AVIATION...
UPDATED 0030Z.
VFR conditions will prevail throughout the TAF period. Mid and upper
clouds will continue to move into the area from the west southwest
with some overnight and early morning isolated showers possible
across Southwest Montana. The confidence of any individual airport
seeing showers is low so have kept only VCSH in for now. Low level
moisture increases after 18Z Thursday as a trough moves in from the
west. Confidence is moderate in the 24 to 36 hour period including
lower ceilings and showers at most of the TAF sites.
&&
.PREV DISCUSSION...Issued 237 PM MDT Wed May 15 2013
Wednesday through Friday...A change in the weather pattern is
expected as the upper level ridge of high pressure slowly exits the
area as a cooler and a generally unsettled weather pattern replaces
it. A large scale trough should begin its approach over the Pacific
Coast by late this evening and will stream moisture in ahead of it.
This upper level diffluence along with above average moisture should
allow for some showers and thunderstorms to develop over the higher
terrain and move off slowly towards the north east. Severe
thunderstorms are not expected at this time...however strong gusty
winds and hail could occur with any of these storms. Temperatures
will begin to return toward seasonal averages and struggle to get
out of the 60s as the short term progress and more moisture flows
into the area with the cooler temperatures. Exact timing of the
larger impulses of upper level support is a point of inconsistency
between the models however the cooler wetter pattern with showers
and afternoon thunderstorms should carry into the long term
forecast. Suk
Friday night through Wednesday...An unsettled weather pattern is
expected through much of the period as a broad trough moves into the
area Friday night. This trough will be the dominate weather feature
through the weekend before pushing east Monday evening. By Tuesday
the next upper level low is positioned off the Pac NW coast. Even
with the trough in place temperatures will be near normal.
Precipitation on Friday evening will be mostly confined to the
southwest. However by Saturday and Sunday the area of afternoon
thunderstorms expands into north-central Montana. Model soundings
show deep moisture and some instability...mostly Saturday
afternoon...however there is not good spatial agreement with
convective parameters such as CAPE...shear and LIs. So do not expect
a lot of svr t-storms over the weekend. By Monday and Tuesday models
start to differ regarding the strength of ridging which tries to
make its way into Montana. The EC model is the strongest and
warmest. The current forecast is a model blend with a little more
weight with the EC. This is short-lived as the affects of the next
upper-level low off the Pac NW coast starts to move into western and
central Montana by mid to late week. Mercer
&&
.HYDROLOGY...
Increased releases out of Gibson Reservoir are causing rises along
the Sun River and the higher flows are expected to continue at
least through this week. At this time, these rises are not
expected to exceed flood stage. Elsewhere, cooler temperatures will
moderate the melting of the snowpack. However, the increased chance
of precipitation will also increase the chance for further
rises in rivers and streams across much of north central and
southwest Montana through the upcoming weekend.
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 43 65 42 62 / 20 50 30 40
CTB 40 65 38 63 / 20 50 30 30
HLN 47 66 43 61 / 20 50 40 50
BZN 44 68 41 63 / 30 60 50 60
WEY 42 62 39 60 / 30 60 50 60
DLN 43 65 40 60 / 20 60 50 60
HVR 45 70 43 71 / 10 50 40 20
LWT 44 63 41 61 / 20 60 50 40
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
weather.gov/greatfalls
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1239 PM CDT TUE MAY 14 2013
.UPDATE...
ISSUED AT 1238 PM CDT TUE MAY 14 2013
LITTLE CHANGE FOR THIS UPDATE. TWEAKED TEMPS AND DEW POINTS TO
MATCH THE CURVE HOWEVER DID NOT ALTER MAX T OR MIN RH. IN THE LAST
HOUR HAVE HAD WINDS STARTING TO PICK UP WITH GUSTS BETWEEN 30 AND
38 KTS. WIND AND RED FLAG HEADLINES IN EFFECT TO 9PM LOOK APROPOS.
UPDATE ISSUED AT 959 AM CDT TUE MAY 14 2013
SHOWERS HAVE EXITED THE AREA AND HAVE REMOVED POPS FOR ALL BUT THE
NORTHERN RRV INTO THE LAKE OF THE WOODS AREA FOR POSSIBLE
REDEVELOPMENT THIS AFTERNOON. AS OF 14Z WEST WIND SHIFT JUST EAST
OF BISMARCK NORTH TO MCCLUSKY NEAR RUGBY TO BOTTINEAU. BEHIND THE
FROPA STILL EXPECTING EFFICIENT MIXING TO 750MB...ALLOWING FOR
RAPID WARM UP. GUSTS BETWEEN 40 AND 50 MPH STILL EXPECTED.
UPDATE ISSUED AT 658 AM CDT TUE MAY 14 2013
SHOWERS AND THUNDERSTORMS HAVE BECOME MORE NUMEROUS ACROSS THE
FORECAST AREA...WITH A STRONG LINE SEGMENT PRODUCING SPORADIC
SEVERE (50+ KTS) DOWNBURST WINDS ACROSS BARNES/CASS COUNTIES.
INCREASED POPS TO 100 PERCENT TO ACCOUNT FOR CURRENT CONVECTIVE
ACTIVITY. ISOLATED STRONG TO SEVERE WINDS ARE POSSIBLE ELSEWHERE
WITH THIS LINE AS ITS FORWARD PROPAGATION IS NEAR 60 MPH. PERSONS
IN THE PATH OF THIS STORM SHOULD PAY CLOSE ATTENTION TO THE LATEST
STATEMENTS AND/OR WARNINGS. REST OF THE FORECAST OK FOR NOW WITH
NO OTHER MAJOR CHANGES.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 355 AM CDT TUE MAY 14 2013
FORECAST CHALLENGES INCLUDE SHOWERS AND THUNDERSTORMS THIS
MORNING...FOLLOWED BY STRONG WINDS AND CRITICAL FIRE WEATHER
CONDITIONS THIS AFTERNOON. GFS/NAM/ECMWF/GEM ARE IN GOOD
AGREEMENT...BUT WILL USE LATEST HRRR FOR PRECIPITATION TRENDS
THROUGH 18 UTC. THEREAFTER...A BLENDED SOLUTION SHOULD SUFFICE.
08 UTC WATER VAPOR LOOP SHOWS A STRONG...YET PROGRESSIVE SHORT
WAVE MOVING ALONG THE CANADIAN BORDER AND INTO NORTHEAST MT. A
CLUSTER OF SHOWERS AND THUNDERSTORMS HAVE DEVELOPED ACROSS CENTRAL
ND IN AN AREA OF WEAK ELEVATED INSTABILITY AND INCREASED
DIVERGENCE ALOFT AHEAD OF A SURFACE COLD FRONT WHICH STRETCHES
FROM NEAR WILLISTON TO MILES CITY MT. LATEST HRRR SHOWS THIS
CONVECTIVE ACTIVITY MOVING EASTWARD THROUGH THE EARLY MORNING AND
INTO THE MN ARROWHEAD AFTER 15 UTC. INCREASED POPS FROM 60 TO 80
PERCENT ACROSS THE NORTHERN HALF OF THE FORECAST AREA THIS MORNING
WHERE A QUICK QUARTER INCH OF RAIN IS POSSIBLE... ESPECIALLY FOR
THOSE AREAS THAT SEE THUNDERSTORMS.
THE COLD FRONT IS FORECAST TO REACH THE VALLEY FLOOR BY 18 UTC.
WITH STRONG LOW-MID LEVEL COLD AIR ADVECTION IN ITS WAKE...AN
ADIABATIC BOUNDARY LAYER TO 750 HPA AND 30 TO 40 KTS TO MIX
DOWN...EXPECT WINDY CONDITIONS TO DEVELOP FROM WEST TO EAST
THROUGH THE AFTERNOON. WEST WINDS FROM 30 TO 40 MPH WITH GUSTS UP
TO 50 MPH ACROSS THE HIGHER TERRAIN OF EASTERN ND NECESSITATES A
WIND ADVISORY FROM 17 TO 02 UTC FOR ALL AREAS EXPECT THE FAR
EASTERN COUNTIES. WILL CANCEL THE HIGH WIND WATCH AS WINDS ARE NOT
EXPECTED TO REACH CRITERIA. HIGH TEMPERATURES TODAY STILL
EXPECTED TO CLIMB INTO THE MID 70S TO MID 80S BEFORE FRONTAL
PASSAGE AND WHEN COMBINED WITH STRONG WINDS AND LOW RH WILL CREATE
DANGEROUS FIRE WEATHER CONDITIONS. SEE DISCUSSION BELOW FOR MORE
DETAIL.
THIS AFTERNOON THROUGH WEDNESDAY WILL BE DRY AS SURFACE HIGH
PRESSURE BUILDS ACROSS THE REGION. WINDS WILL DIMINISH SOMEWHAT
AFTER SUNSET...BUT REMAIN ELEVATED FROM THE WEST-NORTHWEST TONIGHT
THROUGH WEDNESDAY. TOMORROW WILL BE A BIT COOLER WITH AFTERNOON
HIGHS IN THE 70S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 355 AM CDT TUE MAY 14 2013
WEDNESDAY NIGHT THROUGH MOST OF THURSDAY WILL BE DRY...BUT EXPECT
PRECIPITATION CHANCES TO INCREASE THURSDAY NIGHT AHEAD OF THE NEXT
PACIFIC TROUGH. GFS/ECMWF BOTH SHOW A WIDE SWATH OF SHOWERS AND
STORMS MOVING INTO EASTERN ND BY 12 UTC FRIDAY. INCREASED POPS
INTO THE HIGH CHANCE CATEGORY...BUT IF MODEL TRENDS CONTINUE...
WILL NEED TO INCREASE FURTHER. DON/T EXPECT MUCH TEMPERATURE
CHANGE FROM WEDNESDAY WITH THURSDAY/S HIGHS IN THE 70S.
00Z ECMWF/GFS WERE IN GOOD AGREEMENT WITH OVERALL PATTERN FRI-MON
IN SHOWING A LARGE 500 MB TROUGH OVER THE ROCKIES LIFTING
NORTHEAST INTO THE NRN PLAINS AND EVENTUAL 500 MB LOW FORMATION IN
MINNESOTA. THIS LEADS TO AN EXTENDED PERIOD OF PRECIPITATION
CHANCES THRU THE PD. SHOWWALTERS FROM THE MODELS PROG INDICATE
SOME THUNDERSTORM POTENTIAL FRI-SUN THEN MOSTLY SHOWERS ON MONDAY.
OVER THE 4 DAY PERIOD...SOME HEAVY RAINFALL TOTALS ARE POSSIBLE
SOMEWHERE IN OUR REGION AS PWATS INCREASE TO 1.50 INCHES OVER SE
ND INTO NRN MN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1238 PM CDT TUE MAY 14 2013
IT WILL BE VERY WINDY THROUGH THIS EVENING...WITH WEST TO NORTHWEST
WINDS GUSTING TO AROUND 35KT AT TIMES. CIGS WILL REMAIN IN THE VFR
CATEGORY WITH MAINLY HIGH CLOUDS AND SOME SHALLOW CUMULUS THIS
AFTERNOON MAINLY IN THE NORTH. WINDS WILL TURN MORE NORTHERLY AFTER
SUNSET AND DECREASE OVERNIGHT.
&&
.FIRE WEATHER...
ISSUED AT 959 AM CDT TUE MAY 14 2013
RED FLAG WARNING CONTINUES FOR ALL OF ERN ND INTO MUCH OF NW/WCNTRL
MN (EXCEPT LAKE OF THE WOODS AND NORTH BELTRAMI REGIONS) FOR 17Z TUE
TO 02Z WED. FUELS REMAIN DRY AND PRIME. WILDFIRE ONGOING NEAR GRYGLA
IN SOUTHEASTERN MARSHALL COUNTY. FUELS REMAIN DRY IN ERN ND AS
WELL...THOUGH PARTS OF NE ND AND FAR NW MN WILL SEE SOME RAINFALL
THIS MORNING. BELIEVE THAT EARLY MORNING LOW PCPN AMTS WILL NOT HAVE
GREAT IMPACT ON DECREASING HUMIDITIES THIS AFTERNOON AS DEEP MIXING
LAYER COMBINES WITH STRONG WEST NORTHWEST WINDS TO YIELD VALUES
BELOW 25 PERCENT EVEN IN WEST CENTRAL MN. WILL MONITOR HUMIDITY
LEVELS THROUGHOUT THE DAY AND ADJUST ACCORDINGLY.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...RED FLAG WARNING UNTIL 9 PM CDT THIS EVENING FOR NDZ006>008-
014>016-024-026>030-038-039-049-052>054.
WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR NDZ006>008-014>016-
024-026>030-038-039-049-052>054.
MN...RED FLAG WARNING UNTIL 9 PM CDT THIS EVENING FOR MNZ001>005-007-
008-013>017-022>024-027>032-040.
WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR MNZ001>005-007-008-
013>016-022-023-027>031-040.
&&
$$
UPDATE...JK
SHORT TERM...ROGERS
LONG TERM...ROGERS/RIDDLE
AVIATION...DK
FIRE WEATHER...WJB
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
959 AM CDT TUE MAY 14 2013
.UPDATE...
ISSUED AT 959 AM CDT TUE MAY 14 2013
SHOWERS HAVE EXITED THE AREA AND HAVE REMOVED POPS FOR ALL BUT THE
NORTHERN RRV INTO THE LAKE OF THE WOODS AREA FOR POSSIBLE
REDEVELOPMENT THIS AFTERNOON. AS OF 14Z WEST WIND SHIFT JUST EAST
OF BISMARCK NORTH TO MCCLUSKY NEAR RUGBY TO BOTTINEAU. BEHIND THE
FROPA STILL EXPECTING EFFICIENT MIXING TO 750MB...ALLOWING FOR
RAPID WARM UP. GUSTS BETWEEN 40 AND 50 MPH STILL EXPECTED.
UPDATE ISSUED AT 658 AM CDT TUE MAY 14 2013
SHOWERS AND THUNDERSTORMS HAVE BECOME MORE NUMEROUS ACROSS THE
FORECAST AREA...WITH A STRONG LINE SEGMENT PRODUCING SPORADIC
SEVERE (50+ KTS) DOWNBURST WINDS ACROSS BARNES/CASS COUNTIES.
INCREASED POPS TO 100 PERCENT TO ACCOUNT FOR CURRENT CONVECTIVE
ACTIVITY. ISOLATED STRONG TO SEVERE WINDS ARE POSSIBLE ELSEWHERE
WITH THIS LINE AS ITS FORWARD PROPAGATION IS NEAR 60 MPH. PERSONS
IN THE PATH OF THIS STORM SHOULD PAY CLOSE ATTENTION TO THE LATEST
STATEMENTS AND/OR WARNINGS. REST OF THE FORECAST OK FOR NOW WITH
NO OTHER MAJOR CHANGES.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 355 AM CDT TUE MAY 14 2013
FORECAST CHALLENGES INCLUDE SHOWERS AND THUNDERSTORMS THIS
MORNING...FOLLOWED BY STRONG WINDS AND CRITICAL FIRE WEATHER
CONDITIONS THIS AFTERNOON. GFS/NAM/ECMWF/GEM ARE IN GOOD
AGREEMENT...BUT WILL USE LATEST HRRR FOR PRECIPITATION TRENDS
THROUGH 18 UTC. THEREAFTER...A BLENDED SOLUTION SHOULD SUFFICE.
08 UTC WATER VAPOR LOOP SHOWS A STRONG...YET PROGRESSIVE SHORT
WAVE MOVING ALONG THE CANADIAN BORDER AND INTO NORTHEAST MT. A
CLUSTER OF SHOWERS AND THUNDERSTORMS HAVE DEVELOPED ACROSS CENTRAL
ND IN AN AREA OF WEAK ELEVATED INSTABILITY AND INCREASED
DIVERGENCE ALOFT AHEAD OF A SURFACE COLD FRONT WHICH STRETCHES
FROM NEAR WILLISTON TO MILES CITY MT. LATEST HRRR SHOWS THIS
CONVECTIVE ACTIVITY MOVING EASTWARD THROUGH THE EARLY MORNING AND
INTO THE MN ARROWHEAD AFTER 15 UTC. INCREASED POPS FROM 60 TO 80
PERCENT ACROSS THE NORTHERN HALF OF THE FORECAST AREA THIS MORNING
WHERE A QUICK QUARTER INCH OF RAIN IS POSSIBLE... ESPECIALLY FOR
THOSE AREAS THAT SEE THUNDERSTORMS.
THE COLD FRONT IS FORECAST TO REACH THE VALLEY FLOOR BY 18 UTC.
WITH STRONG LOW-MID LEVEL COLD AIR ADVECTION IN ITS WAKE...AN
ADIABATIC BOUNDARY LAYER TO 750 HPA AND 30 TO 40 KTS TO MIX
DOWN...EXPECT WINDY CONDITIONS TO DEVELOP FROM WEST TO EAST
THROUGH THE AFTERNOON. WEST WINDS FROM 30 TO 40 MPH WITH GUSTS UP
TO 50 MPH ACROSS THE HIGHER TERRAIN OF EASTERN ND NECESSITATES A
WIND ADVISORY FROM 17 TO 02 UTC FOR ALL AREAS EXPECT THE FAR
EASTERN COUNTIES. WILL CANCEL THE HIGH WIND WATCH AS WINDS ARE NOT
EXPECTED TO REACH CRITERIA. HIGH TEMPERATURES TODAY STILL
EXPECTED TO CLIMB INTO THE MID 70S TO MID 80S BEFORE FRONTAL
PASSAGE AND WHEN COMBINED WITH STRONG WINDS AND LOW RH WILL CREATE
DANGEROUS FIRE WEATHER CONDITIONS. SEE DISCUSSION BELOW FOR MORE
DETAIL.
THIS AFTERNOON THROUGH WEDNESDAY WILL BE DRY AS SURFACE HIGH
PRESSURE BUILDS ACROSS THE REGION. WINDS WILL DIMINISH SOMEWHAT
AFTER SUNSET...BUT REMAIN ELEVATED FROM THE WEST-NORTHWEST TONIGHT
THROUGH WEDNESDAY. TOMORROW WILL BE A BIT COOLER WITH AFTERNOON
HIGHS IN THE 70S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 355 AM CDT TUE MAY 14 2013
WEDNESDAY NIGHT THROUGH MOST OF THURSDAY WILL BE DRY...BUT EXPECT
PRECIPITATION CHANCES TO INCREASE THURSDAY NIGHT AHEAD OF THE NEXT
PACIFIC TROUGH. GFS/ECMWF BOTH SHOW A WIDE SWATH OF SHOWERS AND
STORMS MOVING INTO EASTERN ND BY 12 UTC FRIDAY. INCREASED POPS
INTO THE HIGH CHANCE CATEGORY...BUT IF MODEL TRENDS CONTINUE...
WILL NEED TO INCREASE FURTHER. DON/T EXPECT MUCH TEMPERATURE
CHANGE FROM WEDNESDAY WITH THURSDAY/S HIGHS IN THE 70S.
00Z ECMWF/GFS WERE IN GOOD AGREEMENT WITH OVERALL PATTERN FRI-MON
IN SHOWING A LARGE 500 MB TROUGH OVER THE ROCKIES LIFTING
NORTHEAST INTO THE NRN PLAINS AND EVENTUAL 500 MB LOW FORMATION IN
MINNESOTA. THIS LEADS TO AN EXTENDED PERIOD OF PRECIPITATION
CHANCES THRU THE PD. SHOWWALTERS FROM THE MODELS PROG INDICATE
SOME THUNDERSTORM POTENTIAL FRI-SUN THEN MOSTLY SHOWERS ON MONDAY.
OVER THE 4 DAY PERIOD...SOME HEAVY RAINFALL TOTALS ARE POSSIBLE
SOMEWHERE IN OUR REGION AS PWATS INCREASE TO 1.50 INCHES OVER SE
ND INTO NRN MN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 959 AM CDT TUE MAY 14 2013
EXPECT STRONG WEST- NORTHWEST WIND TO DEVELOP AND CONTINUE THROUGH
THE AFTERNOON WITH GUSTS UP TO 40 KTS POSSIBLE... ESPECIALLY AT
KDVL/KGFK/KFAR. CONDITIONS WILL IMPROVE MARKEDLY LATER THIS
EVENING AND OVERNIGHT.
&&
.FIRE WEATHER...
ISSUED AT 959 AM CDT TUE MAY 14 2013
RED FLAG WARNING CONTINUES FOR ALL OF ERN ND INTO MUCH OF NW/WCNTRL
MN (EXCEPT LAKE OF THE WOODS AND NORTH BELTRAMI REGIONS) FOR 17Z TUE
TO 02Z WED. FUELS REMAIN DRY AND PRIME. WILDFIRE ONGOING NEAR GRYGLA
IN SOUTHEASTERN MARSHALL COUNTY. FUELS REMAIN DRY IN ERN ND AS
WELL...THOUGH PARTS OF NE ND AND FAR NW MN WILL SEE SOME RAINFALL
THIS MORNING. BELIEVE THAT EARLY MORNING LOW PCPN AMTS WILL NOT HAVE
GREAT IMPACT ON DECREASING HUMIDITIES THIS AFTERNOON AS DEEP MIXING
LAYER COMBINES WITH STRONG WEST NORTHWEST WINDS TO YIELD VALUES
BELOW 25 PERCENT EVEN IN WEST CENTRAL MN. WILL MONITOR HUMIDITY
LEVELS THROUGHOUT THE DAY AND ADJUST ACCORDINGLY.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...RED FLAG WARNING UNTIL 9 PM CDT THIS EVENING FOR NDZ006>008-
014>016-024-026>030-038-039-049-052>054.
WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR NDZ006>008-014>016-
024-026>030-038-039-049-052>054.
MN...RED FLAG WARNING UNTIL 9 PM CDT THIS EVENING FOR MNZ001>005-007-
008-013>017-022>024-027>032-040.
WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR MNZ001>005-007-008-
013>016-022-023-027>031-040.
&&
$$
UPDATE...JK
SHORT TERM...ROGERS
LONG TERM...ROGERS/RIDDLE
AVIATION...TG
FIRE WEATHER...WJB
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
658 AM CDT TUE MAY 14 2013
.UPDATE...
ISSUED AT 658 AM CDT TUE MAY 14 2013
SHOWERS AND THUNDERSTORMS HAVE BECOME MORE NUMEROUS ACROSS THE
FORECAST AREA...WITH A STRONG LINE SEGMENT PRODUCING SPORADIC
SEVERE (50+ KTS) DOWNBURST WINDS ACROSS BARNES/CASS COUNTIES.
INCREASED POPS TO 100 PERCENT TO ACCOUNT FOR CURRENT CONVECTIVE
ACTIVITY. ISOLATED STRONG TO SEVERE WINDS ARE POSSIBLE ELSEWHERE
WITH THIS LINE AS ITS FORWARD PROPAGATION IS NEAR 60 MPH. PERSONS
IN THE PATH OF THIS STORM SHOULD PAY CLOSE ATTENTION TO THE LATEST
STATEMENTS AND/OR WARNINGS. REST OF THE FORECAST OK FOR NOW WITH
NO OTHER MAJOR CHANGES.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 355 AM CDT TUE MAY 14 2013
FORECAST CHALLENGES INCLUDE SHOWERS AND THUNDERSTORMS THIS
MORNING...FOLLOWED BY STRONG WINDS AND CRITICAL FIRE WEATHER
CONDITIONS THIS AFTERNOON. GFS/NAM/ECMWF/GEM ARE IN GOOD
AGREEMENT...BUT WILL USE LATEST HRRR FOR PRECIPITATION TRENDS
THROUGH 18 UTC. THEREAFTER...A BLENDED SOLUTION SHOULD SUFFICE.
08 UTC WATER VAPOR LOOP SHOWS A STRONG...YET PROGRESSIVE SHORT
WAVE MOVING ALONG THE CANADIAN BORDER AND INTO NORTHEAST MT. A
CLUSTER OF SHOWERS AND THUNDERSTORMS HAVE DEVELOPED ACROSS CENTRAL
ND IN AN AREA OF WEAK ELEVATED INSTABILITY AND INCREASED
DIVERGENCE ALOFT AHEAD OF A SURFACE COLD FRONT WHICH STRETCHES
FROM NEAR WILLISTON TO MILES CITY MT. LATEST HRRR SHOWS THIS
CONVECTIVE ACTIVITY MOVING EASTWARD THROUGH THE EARLY MORNING AND
INTO THE MN ARROWHEAD AFTER 15 UTC. INCREASED POPS FROM 60 TO 80
PERCENT ACROSS THE NORTHERN HALF OF THE FORECAST AREA THIS MORNING
WHERE A QUICK QUARTER INCH OF RAIN IS POSSIBLE... ESPECIALLY FOR
THOSE AREAS THAT SEE THUNDERSTORMS.
THE COLD FRONT IS FORECAST TO REACH THE VALLEY FLOOR BY 18 UTC.
WITH STRONG LOW-MID LEVEL COLD AIR ADVECTION IN ITS WAKE...AN
ADIABATIC BOUNDARY LAYER TO 750 HPA AND 30 TO 40 KTS TO MIX
DOWN...EXPECT WINDY CONDITIONS TO DEVELOP FROM WEST TO EAST
THROUGH THE AFTERNOON. WEST WINDS FROM 30 TO 40 MPH WITH GUSTS UP
TO 50 MPH ACROSS THE HIGHER TERRAIN OF EASTERN ND NECESSITATES A
WIND ADVISORY FROM 17 TO 02 UTC FOR ALL AREAS EXPECT THE FAR
EASTERN COUNTIES. WILL CANCEL THE HIGH WIND WATCH AS WINDS ARE NOT
EXPECTED TO REACH CRITERIA. HIGH TEMPERATURES TODAY STILL
EXPECTED TO CLIMB INTO THE MID 70S TO MID 80S BEFORE FRONTAL
PASSAGE AND WHEN COMBINED WITH STRONG WINDS AND LOW RH WILL CREATE
DANGEROUS FIRE WEATHER CONDITIONS. SEE DISCUSSION BELOW FOR MORE
DETAIL.
THIS AFTERNOON THROUGH WEDNESDAY WILL BE DRY AS SURFACE HIGH
PRESSURE BUILDS ACROSS THE REGION. WINDS WILL DIMINISH SOMEWHAT
AFTER SUNSET...BUT REMAIN ELEVATED FROM THE WEST-NORTHWEST TONIGHT
THROUGH WEDNESDAY. TOMORROW WILL BE A BIT COOLER WITH AFTERNOON
HIGHS IN THE 70S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 355 AM CDT TUE MAY 14 2013
WEDNESDAY NIGHT THROUGH MOST OF THURSDAY WILL BE DRY...BUT EXPECT
PRECIPITATION CHANCES TO INCREASE THURSDAY NIGHT AHEAD OF THE NEXT
PACIFIC TROUGH. GFS/ECMWF BOTH SHOW A WIDE SWATH OF SHOWERS AND
STORMS MOVING INTO EASTERN ND BY 12 UTC FRIDAY. INCREASED POPS
INTO THE HIGH CHANCE CATEGORY...BUT IF MODEL TRENDS CONTINUE...
WILL NEED TO INCREASE FURTHER. DON/T EXPECT MUCH TEMPERATURE
CHANGE FROM WEDNESDAY WITH THURSDAY/S HIGHS IN THE 70S.
00Z ECMWF/GFS WERE IN GOOD AGREEMENT WITH OVERALL PATTERN FRI-MON
IN SHOWING A LARGE 500 MB TROUGH OVER THE ROCKIES LIFTING
NORTHEAST INTO THE NRN PLAINS AND EVENTUAL 500 MB LOW FORMATION IN
MINNESOTA. THIS LEADS TO AN EXTENDED PERIOD OF PRECIPITATION
CHANCES THRU THE PD. SHOWWALTERS FROM THE MODELS PROG INDICATE
SOME THUNDERSTORM POTENTIAL FRI-SUN THEN MOSTLY SHOWERS ON MONDAY.
OVER THE 4 DAY PERIOD...SOME HEAVY RAINFALL TOTALS ARE POSSIBLE
SOMEWHERE IN OUR REGION AS PWATS INCREASE TO 1.50 INCHES OVER SE
ND INTO NRN MN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 658 AM CDT TUE MAY 14 2013
AN AREA OF SHOWERS AND THUNDERSTORMS ALONG AND EAST OF THE VALLEY
WILL MOVE RAPIDLY INTO THE MN ARROWHEAD LATER THIS MORNING.
CEILINGS ARE VFR...BUT BRIEF HIGH WIND GUSTS ARE POSSIBLE WITH THE
LEADING EDGE OF STORMS. EXPECT STRONG WEST-NORTHWEST WIND TO
DEVELOP LATER THIS MORNING AND CONTINUE THROUGH THE AFTERNOON WITH
GUSTS UP TO 40 KTS POSSIBLE...ESPECIALLY AT KDVL/KGFK/KFAR.
CONDITIONS WILL IMPROVE MARKEDLY LATER THIS EVENING AND OVERNIGHT.
&&
.FIRE WEATHER...
ISSUED AT 355 AM CDT TUE MAY 14 2013
WILL ISSUE RED FLAG WARNING FOR ALL OF ERN ND INTO MUCH OF NW/WCNTRL
MN (EXCEPT LAKE OF THE WOODS AND NORTH BELTRAMI REGIONS) FOR 17Z TUE
TO 02Z WED. EVENING DISCUSSION WITH MN FIRE AGENCY INDICATES FUELS
ARE DRY AND PRIME. WILDFIRE ONGOING NEAR GRYGLA IN SOUTHEASTERN
MARSHALL COUNTY. FUELS REMAIN DRY IN ERN ND AS WELL...THOUGH PARTS
OF NE ND AND FAR NW MN WILL SEE SOME RAINFALL THIS MORNING. THE
EXTENT OF RAINFALL THIS MORNING IS STILL UNCERTAIN. AIDING IN FIRE
POTENTIAL IS STRONG WESTERLY WINDS THAT WILL SPREAD EAST BEHIND
THE COLD FRONT INTO ERN ND MIDDAY AND INTO NW/WCNTRL MN THIS AFTN
WITH GUSTS 40-50 MPH IN ERN ND AND 35 TO 45 MPH IN THE PRAIRIE
REGIONS OF NW/WCNTRL MN. THUS RED FLAG WARNING ISSUED. NOW HOURLY
TRENDS OF RELATIVE HUMIDITY WILL BE A CHALLENGE AND VERY DIFFICULT
TO FORECAST FOR DUE TO IMPACTS OF ANY MORNING PRECIP AND LOCATION.
THUS COULD HAVE WIDE VARIATIONS THIS MORNING-MIDDAY UNTIL THE
FRONT AND WESTERLY WINDS ARRIVE.
&&
.HYDROLOGY...
ISSUED AT 1258 PM CDT MON MAY 13 2013
RIVER FLOOD WARNINGS CONTINUE ON THE RED RIVER AT OSLO...DRAYTON
AND PEMBINA. RIVER STAGES AT DRAYTON AND PEMBINA ARE CONTINUING A
SLOW RECESSION...WITH STAGES AT OSLO FALLING MORE RAPIDLY.
OTHERWISE...MOST OTHER POINTS ON THE MAINSTEM RED AND ON THE ND/MN
TRIBUTARIES SHOW RECEDING OR NEARLY STEADY LEVELS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...RED FLAG WARNING FROM NOON TODAY TO 9 PM CDT THIS EVENING FOR
NDZ006>008-014>016-024-026>030-038-039-049-052>054.
WIND ADVISORY FROM NOON TODAY TO 9 PM CDT THIS EVENING FOR
NDZ006>008-014>016-024-026>030-038-039-049-052>054.
MN...RED FLAG WARNING FROM NOON TODAY TO 9 PM CDT THIS EVENING FOR
MNZ001>005-007-008-013>017-022>024-027>032-040.
WIND ADVISORY FROM NOON TODAY TO 9 PM CDT THIS EVENING FOR
MNZ001>005-007-008-013>016-022-023-027>031-040.
&&
$$
UPDATE...ROGERS
SHORT TERM...ROGERS
LONG TERM...ROGERS/RIDDLE
AVIATION...ROGERS
FIRE WEATHER...RIDDLE
HYDROLOGY...SPEICHER
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
355 AM CDT TUE MAY 14 2013
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 355 AM CDT TUE MAY 14 2013
FORECAST CHALLENGES INCLUDE SHOWERS AND THUNDERSTORMS THIS
MORNING...FOLLOWED BY STRONG WINDS AND CRITICAL FIRE WEATHER
CONDITIONS THIS AFTERNOON. GFS/NAM/ECMWF/GEM ARE IN GOOD
AGREEMENT...BUT WILL USE LATEST HRRR FOR PRECIPITATION TRENDS
THROUGH 18 UTC. THEREAFTER...A BLENDED SOLUTION SHOULD SUFFICE.
08 UTC WATER VAPOR LOOP SHOWS A STRONG...YET PROGRESSIVE SHORT
WAVE MOVING ALONG THE CANADIAN BORDER AND INTO NORTHEAST MT. A
CLUSTER OF SHOWERS AND THUNDERSTORMS HAVE DEVELOPED ACROSS CENTRAL
ND IN AN AREA OF WEAK ELEVATED INSTABILITY AND INCREASED
DIVERGENCE ALOFT AHEAD OF A SURFACE COLD FRONT WHICH STRETCHES
FROM NEAR WILLISTON TO MILES CITY MT. LATEST HRRR SHOWS THIS
CONVECTIVE ACTIVITY MOVING EASTWARD THROUGH THE EARLY MORNING AND
INTO THE MN ARROWHEAD AFTER 15 UTC. INCREASED POPS FROM 60 TO 80
PERCENT ACROSS THE NORTHERN HALF OF THE FORECAST AREA THIS MORNING
WHERE A QUICK QUARTER INCH OF RAIN IS POSSIBLE... ESPECIALLY FOR
THOSE AREAS THAT SEE THUNDERSTORMS.
THE COLD FRONT IS FORECAST TO REACH THE VALLEY FLOOR BY 18 UTC.
WITH STRONG LOW-MID LEVEL COLD AIR ADVECTION IN ITS WAKE...AN
ADIABATIC BOUNDARY LAYER TO 750 HPA AND 30 TO 40 KTS TO MIX
DOWN...EXPECT WINDY CONDITIONS TO DEVELOP FROM WEST TO EAST
THROUGH THE AFTERNOON. WEST WINDS FROM 30 TO 40 MPH WITH GUSTS UP
TO 50 MPH ACROSS THE HIGHER TERRAIN OF EASTERN ND NECESSITATES A
WIND ADVISORY FROM 17 TO 02 UTC FOR ALL AREAS EXPECT THE FAR
EASTERN COUNTIES. WILL CANCEL THE HIGH WIND WATCH AS WINDS ARE NOT
EXPECTED TO REACH CRITERIA. HIGH TEMPERATURES TODAY STILL
EXPECTED TO CLIMB INTO THE MID 70S TO MID 80S BEFORE FRONTAL
PASSAGE AND WHEN COMBINED WITH STRONG WINDS AND LOW RH WILL CREATE
DANGEROUS FIRE WEATHER CONDITIONS. SEE DISCUSSION BELOW FOR MORE
DETAIL.
THIS AFTERNOON THROUGH WEDNESDAY WILL BE DRY AS SURFACE HIGH
PRESSURE BUILDS ACROSS THE REGION. WINDS WILL DIMINISH SOMEWHAT
AFTER SUNSET...BUT REMAIN ELEVATED FROM THE WEST-NORTHWEST TONIGHT
THROUGH WEDNESDAY. TOMORROW WILL BE A BIT COOLER WITH AFTERNOON
HIGHS IN THE 70S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 355 AM CDT TUE MAY 14 2013
WEDNESDAY NIGHT THROUGH MOST OF THURSDAY WILL BE DRY...BUT EXPECT
PRECIPITATION CHANCES TO INCREASE THURSDAY NIGHT AHEAD OF THE NEXT
PACIFIC TROUGH. GFS/ECMWF BOTH SHOW A WIDE SWATH OF SHOWERS AND
STORMS MOVING INTO EASTERN ND BY 12 UTC FRIDAY. INCREASED POPS
INTO THE HIGH CHANCE CATEGORY...BUT IF MODEL TRENDS CONTINUE...
WILL NEED TO INCREASE FURTHER. DON/T EXPECT MUCH TEMPERATURE
CHANGE FROM WEDNESDAY WITH THURSDAY/S HIGHS IN THE 70S.
00Z ECMWF/GFS WERE IN GOOD AGREEMENT WITH OVERALL PATTERN FRI-MON
IN SHOWING A LARGE 500 MB TROUGH OVER THE ROCKIES LIFTING
NORTHEAST INTO THE NRN PLAINS AND EVENTUAL 500 MB LOW FORMATION IN
MINNESOTA. THIS LEADS TO AN EXTENDED PERIOD OF PRECIPITATION
CHANCES THRU THE PD. SHOWWALTERS FROM THE MODELS PROG INDICATE
SOME THUNDERSTORM POTENTIAL FRI-SUN THEN MOSTLY SHOWERS ON MONDAY.
OVER THE 4 DAY PERIOD...SOME HEAVY RAINFALL TOTALS ARE POSSIBLE
SOMEWHERE IN OUR REGION AS PWATS INCREASE TO 1.50 INCHES OVER SE
ND INTO NRN MN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1154 PM CDT MON MAY 13 2013
VFR CONDITIONS WILL CONTINUE THROUGHOUT THE PERIOD. A FEW SHOWERS
OR THUNDERSTORMS ARE POSSIBLE 09Z AND AFTER AROUND KDVL AND
FURTHER EAST LATER ON. WINDS WILL PICK UP OUT OF THE WEST AFTER
18Z WITH 20 TO 30 KTS AND GUSTS ABOVE 35 KTS. WINDS WILL DIMINISH
AFTER 01Z WEDNESDAY.
&&
.FIRE WEATHER...
ISSUED AT 355 AM CDT TUE MAY 14 2013
WILL ISSUE RED FLAG WARNING FOR ALL OF ERN ND INTO MUCH OF NW/WCNTRL
MN (EXCEPT LAKE OF THE WOODS AND NORTH BELTRAMI REGIONS) FOR 17Z TUE
TO 02Z WED. EVENING DISCUSSION WITH MN FIRE AGENCY INDICATES FUELS
ARE DRY AND PRIME. WILDFIRE ONGOING NEAR GRYGLA IN SOUTHEASTERN
MARSHALL COUNTY. FUELS REMAIN DRY IN ERN ND AS WELL...THOUGH PARTS
OF NE ND AND FAR NW MN WILL SEE SOME RAINFALL THIS MORNING. THE
EXTENT OF RAINFALL THIS MORNING IS STILL UNCERTAIN. AIDING IN FIRE
POTENTIAL IS STRONG WESTERLY WINDS THAT WILL SPREAD EAST BEHIND
THE COLD FRONT INTO ERN ND MIDDAY AND INTO NW/WCNTRL MN THIS AFTN
WITH GUSTS 40-50 MPH IN ERN ND AND 35 TO 45 MPH IN THE PRAIRIE
REGIONS OF NW/WCNTRL MN. THUS RED FLAG WARNING ISSUED. NOW HOURLY
TRENDS OF RELATIVE HUMIDITY WILL BE A CHALLENGE AND VERY DIFFICULT
TO FORECAST FOR DUE TO IMPACTS OF ANY MORNING PRECIP AND LOCATION.
THUS COULD HAVE WIDE VARIATIONS THIS MORNING-MIDDAY UNTIL THE
FRONT AND WESTERLY WINDS ARRIVE.
&&
.HYDROLOGY...
ISSUED AT 1258 PM CDT MON MAY 13 2013
RIVER FLOOD WARNINGS CONTINUE ON THE RED RIVER AT OSLO...DRAYTON
AND PEMBINA. RIVER STAGES AT DRAYTON AND PEMBINA ARE CONTINUING A
SLOW RECESSION...WITH STAGES AT OSLO FALLING MORE RAPIDLY.
OTHERWISE...MOST OTHER POINTS ON THE MAINSTEM RED AND ON THE ND/MN
TRIBUTARIES SHOW RECEDING OR NEARLY STEADY LEVELS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...RED FLAG WARNING FROM NOON TODAY TO 9 PM CDT THIS EVENING FOR
NDZ006>008-014>016-024-026>030-038-039-049-052>054.
WIND ADVISORY FROM NOON TODAY TO 9 PM CDT THIS EVENING FOR
NDZ006>008-014>016-024-026>030-038-039-049-052>054.
MN...RED FLAG WARNING FROM NOON TODAY TO 9 PM CDT THIS EVENING FOR
MNZ001>005-007-008-013>017-022>024-027>032-040.
WIND ADVISORY FROM NOON TODAY TO 9 PM CDT THIS EVENING FOR
MNZ001>005-007-008-013>016-022-023-027>031-040.
&&
$$
SHORT TERM...ROGERS
LONG TERM...ROGERS/RIDDLE
AVIATION...JR
FIRE WEATHER...RIDDLE
HYDROLOGY...SPEICHER
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
917 PM EDT WED MAY 15 2013
.SYNOPSIS...
A COLD FRONT JUST SOUTH OF THE LAKESHORE WILL PUSH INTO CENTRAL OHIO
TONIGHT AND THEN STALL. THE FRONT WILL LIFT NORTH AS A WARM FRONT
THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
COLD FRONT CURRENTLY SOUTH OF THE LAKESHORE. A COUPLE OF SHOWERS
HAVE POPPED UP JUST SOUTH OF KNOX COUNTY. WILL KEEP THE SLIGHT
CHANCE FOR A SHOWER/TS FROM FINDLAY TO MILLERSBURG. HRRR AND RAP
WANT TO PAINT SOME QPF TONIGHT. WITH BOUNDARY IN THE VICINITY AND
A LITTLE BIT OF ENERGY UPSTREAM...DID NOT WANT A COMPLETELY DRY
FORECAST. FOR TEMPS WENT UPPER 40S TO THE MID 50S. THERE IS ENOUGH
UPSTREAM CLOUDINESS TO GIVE US A VARIABLY CLOUDY OVERNIGHT.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY NIGHT/...
MODELS CONTINUE TO STALL THE FRONT WELL SOUTH OF THE AREA. GFS A
LITTLE SLOWER TODAY MOVING THE FRONT NORTH. EXCEPT FOR THE EXTREME
SW PORTION OF THE FORECAST AREA REMOVED MENTION OF POPS FOR FRIDAY
AND FRIDAY NIGHT. MODELS STILL IN CONFLICT FOR SATURDAY. ECMWF
KEEPS FRONT SOUTH OF THE AREA ON SATURDAY WHILE GFS CONTINUES TO
HAVE THE FRONT ACROSS THE AREA. FOR NOW SEE NO REASON TO START FLIP
FLOPPING FORECASTS THIS FAR OUT WHEN THINGS ARE STILL IN DOUBT. SO
FOR NOW KEPT CHANCE POPS GOING FOR SATURDAY.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
THE RIDGE IS STILL PROGGED TO BUILD ACROSS THE AREA THIS WEEKEND
THROUGH EARLY NEXT WEEK. THE CHANCES OF SHOWERS/STORMS SHOULD
DIMINISH UNDER THE BUILDING RIDGE. CANNOT TOTALLY RULE OUT OUT A
SHOWER OR THUNDERSTORM GIVEN THE OLD FRONTAL BOUNDARY OR SOME
OUTFLOW/MESO BOUNDARY... INCREASING HEAT ETC...BUT FOR THE
MOST PART SUNDAY AND MONDAY SHOULD BE WARM AND MOSTLY RAIN FREE. CUT
BACK ON THE 12 HOUR POP SUNDAY/MONDAY MOSTLY TO 15 TO 25 PERCENT.
THIS WILL BE "SLIGHT CHANCE" IN MOST FORECASTS WHICH DOES NOT SHOW
UP IN MOST OF OUR TEXT FORECASTS (AFTER THE FIRST DAY).
BY THE MIDDLE OF NEXT WEEK THE NEXT FRONT FROM THE WEST SHOULD WORK
INTO THE AREA. IT WILL LIKELY NOT BE IN A HURRY TO MOVE EAST AS A
TROUGH ALOFT IS PROGGED TO BE DEEPENING IN THE MIDDLE OF THE
COUNTRY. WILL HAVE A HIGHER CHANCE OF SHOWERS AND THUNDERSTORMS BY
TUESDAY AND WEDNESDAY. WILL BEGIN TO CUT BACK ON TEMPERATURES BY
NEXT WEDNESDAY GIVEN THE INCREASE IN CLOUDS AND SHOWERS.
FORECAST HIGHS WILL BE ABOVE GUIDANCE GIVEN THE BIG RIDGE AND THE
TIME OF YEAR. HIGHS 75 TO 80 SUNDAY...AROUND 80 OR IN THE LOWER 80S
MONDAY AND TUESDAY...THEN 70S WEDNESDAY. LOWS GENERALLY MID 50S TO
THE LOWER 60S.
&&
.AVIATION /01Z THURSDAY THROUGH MONDAY/...
THE COLD FRONT THAT MOVED THROUGH THE AREA TODAY WAS BECOMING
STATIONARY ACROSS CENTRAL OHIO WITH WEAK HIGH PRESSURE BUILDING INTO
NORTHWEST OHIO. A WEAK IMPULSE ALOFT WILL MOVE ACROSS THE AREA
TONIGHT. SOME MID AND UPPER CLOUDS WERE ASSOCIATED WITH THIS
IMPULSE. IN FACT SOME LIGHT SHOWERS WERE ALSO ASSOCIATED WITH
THAT IMPULSE. THESE SHOWERS ARE EXPECTED TO DISSIPATE BEFORE
GETTING INTO THE AREA.
HOWEVER...WITH THE FRONTAL BOUNDARY WEST TO EAST ACROSS CENTRAL
OHIO A WAVE IS EXPECTED TO MOVE ALONG THE BOUNDARY TONIGHT AS PER
THE RAP AND HRRR MODELS AND THAT MAY CAUSE SOME SHOWERS TO
DEVELOP. AT THIS TIME NOT EXPECTING ANY PRECIPITATION AT THE TAF
SITES. THE SHOWERS WILL BE MAINLY SOUTH OF A FDY TO MFD TO CAK
LINE. SOME CLOUDS AROUND 5000 FEET ARE LIKELY TO DEVELOP IN THAT AREA.
EVEN THOUGH THE WINDS ARE DECREASING THE AIRMASS IS VERY DRY AND
WITH SOME CLOUDS AROUND NOT EXPECTING ANY FOG AT THE TAF SITES.
ISOLATED MVFR FOG MAY DEVELOP AROUND SUNRISE AT SOME FAVORED
LOCATIONS.
THURSDAY WILL BE VFR WITH LIGHT W TO NW WINDS. THE BOUNDARY WILL
REMAIN ACROSS CENTRAL OHIO AND ANY SHOWER OR THUNDERSTORM ACTIVITY
WILL BE WELL SOUTH OF THE FORECAST AREA.
.OUTLOOK... NON-VFR POSSIBLE IN SHOWERS OR THUNDERSTORMS
FRIDAY NIGHT THROUGH SUNDAY.
&&
.MARINE...
THE WINDS AND WAVES DECREASED ON SCHEDULE. WILL LET THE SMALL CRAFT
ADVISORY EXPIRE ON THE EAST END. ONLY MINOR CHANGES MADE TO THE
OVERNIGHT FORECAST.
HIGH PRESSURE WILL SLOWLY BUILD EAST ACROSS THE LAKE FROM THURSDAY
THROUGH THE WEEKEND. TEMPERATURES WILL BE ABOVE NORMAL THROUGH THIS
TIME WITH STABLE CONDITIONS ON THE LAKE. WINDS WILL GENERALLY BE
LESS THAN 15 KNOTS WITH WAVES LESS THAN 2 FEET. LOW PRESSURE WILL
SLOWLY APPROACH THE REGION FROM THE WEST EARLY NEXT WEEK BRINGING
INCREASING CHANCES OF SHOWERS AND THUNDERSTORMS.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...DJB
NEAR TERM...DJB/OUDEMAN
SHORT TERM...DJB
LONG TERM...KOSARIK
AVIATION...KIELTYKA
MARINE...KEC/KIELTYKA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
751 PM EDT WED MAY 15 2013
.SYNOPSIS...
A COLD FRONT JUST SOUTH OF THE LAKESHORE WILL PUSH INTO CENTRAL OHIO
TONIGHT AND THEN STALL. THE FRONT WILL LIFT NORTH AS A WARM FRONT
THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
COLD FRONT CURRENTLY SOUTH OF THE LAKESHORE. SHOWERS HAVE ENDED
ACROSS THE SOUTHERN TIER OF COUNTIES. SO HAVE REMOVED THE PRECIP
CHANCES FOR THE REMAINDER OF THE EVENING. DID HOWEVER RE-INTRODUCE
A SLIGHT CHANCE FOR A SHOWER/TS FROM FINDLAY TO MILLERSBURG. HRRR
AND RAP WANT TO PAINT SOME QPF TONIGHT. IT HAS A REASONABLE
PICTURE FOR THE CONDITIONS RIGHT NOW...AND WITH BOUNDARY IN THE
VICINITY AND A LITTLE BIT OF ENERGY UPSTREAM...DID NOT WANT A
COMPLETELY DRY FORECAST. WILL WATCH FOR THIS TONIGHT. FOR TEMPS
WENT UPPER 40S TO THE MID 50S. HOWEVER...BELIEVE THE MODELS
OVERDOING THE CLOUDS TONIGHT...IF THAT IS THE CASE TEMPS WILL BE A
LITTLE LOWER.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY NIGHT/...
MODELS CONTINUE TO STALL THE FRONT WELL SOUTH OF THE AREA. GFS A
LITTLE SLOWER TODAY MOVING THE FRONT NORTH. EXCEPT FOR THE EXTREME
SW PORTION OF THE FORECAST AREA REMOVED MENTION OF POPS FOR FRIDAY
AND FRIDAY NIGHT. MODELS STILL IN CONFLICT FOR SATURDAY. ECMWF
KEEPS FRONT SOUTH OF THE AREA ON SATURDAY WHILE GFS CONTINUES TO
HAVE THE FRONT ACROSS THE AREA. FOR NOW SEE NO REASON TO START FLIP
FLOPPING FORECASTS THIS FAR OUT WHEN THINGS ARE STILL IN DOUBT. SO
FOR NOW KEPT CHANCE POPS GOING FOR SATURDAY.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
THE RIDGE IS STILL PROGGED TO BUILD ACROSS THE AREA THIS WEEKEND
THROUGH EARLY NEXT WEEK. THE CHANCES OF SHOWERS/STORMS SHOULD
DIMINISH UNDER THE BUILDING RIDGE. CANNOT TOTALLY RULE OUT OUT A
SHOWER OR THUNDERSTORM GIVEN THE OLD FRONTAL BOUNDARY OR SOME
OUTFLOW/MESO BOUNDARY... INCREASING HEAT ETC...BUT FOR THE
MOST PART SUNDAY AND MONDAY SHOULD BE WARM AND MOSTLY RAIN FREE. CUT
BACK ON THE 12 HOUR POP SUNDAY/MONDAY MOSTLY TO 15 TO 25 PERCENT.
THIS WILL BE "SLIGHT CHANCE" IN MOST FORECASTS WHICH DOES NOT SHOW
UP IN MOST OF OUR TEXT FORECASTS (AFTER THE FIRST DAY).
BY THE MIDDLE OF NEXT WEEK THE NEXT FRONT FROM THE WEST SHOULD WORK
INTO THE AREA. IT WILL LIKELY NOT BE IN A HURRY TO MOVE EAST AS A
TROUGH ALOFT IS PROGGED TO BE DEEPENING IN THE MIDDLE OF THE
COUNTRY. WILL HAVE A HIGHER CHANCE OF SHOWERS AND THUNDERSTORMS BY
TUESDAY AND WEDNESDAY. WILL BEGIN TO CUT BACK ON TEMPERATURES BY
NEXT WEDNESDAY GIVEN THE INCREASE IN CLOUDS AND SHOWERS.
FORECAST HIGHS WILL BE ABOVE GUIDANCE GIVEN THE BIG RIDGE AND THE
TIME OF YEAR. HIGHS 75 TO 80 SUNDAY...AROUND 80 OR IN THE LOWER 80S
MONDAY AND TUESDAY...THEN 70S WEDNESDAY. LOWS GENERALLY MID 50S TO
THE LOWER 60S.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
THE COLD FRONT THAT MOVED THROUGH THE AREA TODAY WAS BECOMING
STATIONARY ACROSS CENTRAL OHIO WITH WEAK HIGH PRESSURE BUILDING INTO
NORTHWEST OHIO. A WEAK IMPULSE ALOFT WILL MOVE ACROSS THE AREA
TONIGHT. SOME MID AND UPPER CLOUDS WERE ASSOCIATED WITH THIS
IMPULSE. IN FACT SOME LIGHT SHOWERS WERE ALSO ASSOCIATED WITH
THAT IMPULSE. THESE SHOWERS ARE EXPECTED TO DISSIPATE BEFORE
GETTING INTO THE AREA.
HOWEVER...WITH THE FRONTAL BOUNDARY WEST TO EAST ACROSS CENTRAL
OHIO A WAVE IS EXPECTED TO MOVE ALONG THE BOUNDARY TONIGHT AS PER
THE RAP AND HRRR MODELS AND THAT MAY CAUSE SOME SHOWERS TO
DEVELOP. AT THIS TIME NOT EXPECTING ANY PRECIPITATION AT THE TAF
SITES. THE SHOWERS WILL BE MAINLY SOUTH OF A FDY TO MFD TO CAK
LINE. SOME CLOUDS AROUND 5000 FEET ARE LIKELY TO DEVELOP IN THAT AREA.
EVEN THOUGH THE WINDS ARE DECREASING THE AIRMASS IS VERY DRY AND
WITH SOME CLOUDS AROUND NOT EXPECTING ANY FOG AT THE TAF SITES.
ISOLATED MVFR FOG MAY DEVELOP AROUND SUNRISE AT SOME FAVORED
LOCATIONS.
THURSDAY WILL BE VFR WITH LIGHT W TO NW WINDS. THE BOUNDARY WILL
REMAIN ACROSS CENTRAL OHIO AND ANY SHOWER OR THUNDERSTORM ACTIVITY
WILL BE WELL SOUTH OF THE FORECAST AREA.
.OUTLOOK... NON-VFR POSSIBLE IN SHOWERS OR THUNDERSTORMS
FRIDAY NIGHT THROUGH SUNDAY.
&&
.MARINE...
A FAIRLY TIGHT PRESSURE GRADIENT IS IN PLACE ACROSS LAKE ERIE THIS
AFTERNOON EXTENDING FROM LOW PRESSURE APPROACHING JAMES BAY. THIS
TROUGH WILL SHIFT EAST OF THE LAKE THIS EVENING...PUSHING A COLD
FRONT SOUTH ACROSS THE LAKE WITH DECREASING WINDS AND WAVES. THE
SMALL CRAFT ADVISORY WEST OF AVON WILL BE ALLOWED TO EXPIRE AT 4 PM
AND THE ENDING TIME OF 10 PM STILL LOOKS ON TRACK FOR THE EASTERN
PORTION OF THE LAKE.
HIGH PRESSURE WILL SLOWLY BUILD EAST ACROSS THE LAKE FROM THURSDAY
THROUGH THE WEEKEND. TEMPERATURES WILL BE ABOVE NORMAL THROUGH THIS
TIME WITH STABLE CONDITIONS ON THE LAKE. WINDS WILL GENERALLY BE
LESS THAN 15 KNOTS WITH WAVES LESS THAN 2 FEET. LOW PRESSURE WILL
SLOWLY APPROACH THE REGION FROM THE WEST EARLY NEXT WEEK BRINGING
INCREASING CHANCES OF SHOWERS AND THUNDERSTORMS.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR
LEZ146>149.
&&
$$
SYNOPSIS...DJB
NEAR TERM...DJB/OUDEMAN
SHORT TERM...DJB
LONG TERM...KOSARIK
AVIATION...KIELTYKA
MARINE...KEC
AREA FORECAST DISCUSSION...UPDATED
NWS PORTLAND OR
855 PM PDT WED MAY 15 2013
.SYNOPSIS...A SERIES OF UPPER LEVEL DISTURBANCES WILL MOVE THROUGH
THE PACIFIC NW DURING THE LATTER HALF OF THE WEEK...KEEPING A THREAT
OF SHOWERS IN THE FORECAST THROUGH SAT. THERE MAY BE A BREAK IN
SYSTEMS SUN OR MON...THEN A COOLER SYSTEM IS EXPECTED TO DROP DOWN
INTO THE REGION AROUND TUE.
&&
.UPDATE...FOR THE EVENING...THERE IS A BLOSSOMING AREA OF CLOUDS IN
WARM AIR ADVECTION JUST OFFSHORE AND ACTIVITY EVIDENT ON KRTX RADAR
AS WELL BOTH INLAND AND OFFSHORE. MODEL FORECASTS AND WV PICTURES
INDICATE THE DEEPER MOISTURE ASSOCIATED WITH THE NEXT SET OF
SHORTWAVES REMAINS ALONG THE SOUTHERN TIER OF COUNTIES AND INTO
SOUTHERN OREGON...BUT THE HRRR INDICATES ENOUGH ACTIVITY MAKING IT
INTO THE COAST AND COAST RANGE TO WARRANT THE LIKELY POPS FOR MOST
COAST RANGE WEST...LOOKS LIKE SOME RAIN WILL SPREAD INTO THE VALLEY
TONIGHT BUT WILL NOT EVERYWHERE AS THE ECHOES LOOK FRAGMENTED AND
NOT COMPLETELY FILLED IN. THEN IT LOOKS LIKE TOMORROW WE GET
SOME DEFORMATION PRECIPITATION AND A DIURNAL INCREASE RELATED TO THE
UPPER TROUGH BEING RIGHT ON TOP OF US AND THE SHORTWAVE PASSING BY
TO THE SOUTH. HAVE RAISED POPS ACCORDINGLY FOR TOMORROW AFTERNOON.
GENERAL THEME REMAINS THE SAME MENTIONED IN THE SHORT TERM
DISCUSSION BELOW. KMD
.SHORT TERM...SATELLITE DERIVED PRECIPITABLE WATER IMAGES SHOW A
LONG FETCH OF SUBTROPICAL MOISTURE STREAMING ACROSS THE PACIFIC
TOWARDS THE CA OREGON BORDER. IN THE WESTERLY FLOW ALOFT...SEEN IN
WATER VAPOR PICTURES...MODELS DEPICT A SERIES OF SHORTWAVES MOVING
THROUGH. THE FIRST TROUGH JUST OFFSHORE...IS SLOW TO MOVE THROUGH
WITH MULTIPLE EMBEDDED SHORTWAVES AFFECTING THE AREA TONIGHT THROUGH
THU NIGHT. ANOTHER TROUGH...ORIGINATING NEAR 160W...IS FORECAST BY
GFS AND ECMWF TO REACH THE AREA DURING THE DAY SAT. WITH MOIST
ONSHORE FLOW CONTINUING THROUGH THE NEXT SEVERAL DAYS...WILL NEED TO
LEAVE IN SOME POPS THROUGHOUT THE TIME PERIOD...BUT WILL TRY TO
REFLECT ENHANCED POPS TONIGHT THROUGH THU EVENING...AND AGAIN ON SAT.
LATEST LOOK AT BUFR SOUNDINGS SUGGEST AT BEST A MINIMAL THREAT FOR
THUNDERSTORMS WITH THE SHOWERS...MOST LIKELY THU...BUT STILL
PROBABLY NOT WORTH THE MENTION AT THIS POINT. TEMPS THROUGH SAT
LIKELY TO REMAIN NEAR OR SLIGHTLY BELOW NORMAL.
.LONG TERM...SATURDAY EVENING THROUGH WEDNESDAY...THE REMNANTS OF A
FRONTAL SYSTEM WILL MOVE THROUGH THE AREA LATE THIS WEEKEND...
KEEPING THE REGION COOL...CLOUDY AND DAMP. EXPECT BRIEF RIDGING TO
DEVELOP OVER THE PACIFIC NORTHWEST MONDAY...WITH DRY CONDITIONS AND
TEMPERATURES NEAR NORMAL. THE NEXT SIGNIFICANT SYSTEM ARRIVES LATE
MONDAY NIGHT/TUESDAY...WITH SNOW LEVELS DROPPING NEAR CASCADE
PASSES. COOLER AND UNSETTLED WEATHER WILL LINGER THROUGH THE
REMAINDER OF THE WEEK. /27
&&
.AVIATION...THERE WILL BE LITTLE CHANGE IN FLIGHT CONDITIONS
TONIGHT AND THURSDAY AS A SURFACE LOW OFFSHORE WILL CONTINUE
CLOUDY CONDITIONS WITH PERIODS OF LIGHT RAIN. MOSTLY MVFR CIGS
THIS EVENING WITH LOCAL VFR TO THE FAR SOUTH. WIDESPREAD MVFR
CONDITIONS WITH SPOTTY IFR ALONG THE COAST IS EXPECTED AFTER
08Z...AS WELL AS MORE STEADY RAIN. RAIN WITH VARIABLE CIGS AND
VISIBILITIES WILL PERSIST THROUGH MUCH OF THURSDAY. WINDS WILL
WEAKEN TONIGHT AND BE GENERALLY LIGHT AND VARIABLE THURSDAY.
KPDX AND APPROACHES...MOSTLY VFR CONDITIONS FOR THE REST OF THE
EVENING. CIGS WILL LOWER AROUND 10Z WITH MIX OF VFR AND MVFR FOR MOST
OF THURSDAY.
&&
.MARINE...GUSTY WINDS ARE EASING THIS EVENING AND AM GOING TO HAVE
THE SMALL CRAFT ADVISORY FOR THE INNER WATERS EXPIRE AT 9 PM
TONIGHT. THE WINDS WILL CONTINUE TO DECREASE TONIGHT AND THURSDAY
AS A WEAK SURFACE LOW MOVES OVER THE WATERS. WEAK SURFACE PRESSURE
WILL MAINTAIN LIGHT WINDS AND LOW SEAS THROUGH FRIDAY NIGHT. THE
NEXT FRONT THAT MAY CAUSE WINDS TO INCREASE ABOVE 20 KT IS
EXPECTED SATURDAY. SEAS WILL REMAIN BELOW 7 FT THROUGH THE
WEEKEND.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...NONE.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
325 PM CDT TUE MAY 14 2013
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 211 PM CDT TUE MAY 14 2013
FRONT CONTINUES TO MOVE ACROSS THE CWA THIS AFTERNOON. RECORD HEAT
OUT AHEAD OF THE FRONT WITH LOW TO EVEN MID 100S ACROSS NORTHWEST
IOWA AND PORTIONS OF SOUTHWEST MINNESOTA...AND STILL LOW TO MID 90S
BEHIND THE FRONT ACROSS SOUTHEAST SOUTH DAKOTA. WITH DEWPOINTS
MIXING OUT...NOT MUCH IN THE WAY OF INSTABILITY AHEAD OF THE FRONT.
ALTHOUGH THE HRRR AND RUC HAVE CONTINUED TO SHOW SOME ISOLATED
DEVELOPMENT ALONG THE FRONT BY 22Z. GIVEN THAT BOTH OF THESE SHORT
RANGE MODELS ARE DOING A PRETTY GOOD JOB WITH SURFACE TEMPS AND
DEWPOINTS..THINK SOME ISOLATED CONVECTION MAY FIRE AS WE MIX THROUGH
WHATEVER CAP THERE IS. HOWEVER LOOKS LIKE THIS THREAT IS MAINLY
SOUTH AND SOUTHEAST OF OUR CWA...THUS WILL KEEP THE FORECAST DRY
THROUGH THE EVENING. WEAK COLD AIR ADVECTION CONTINUES THROUGH THE
NIGHT...WITH WINDS WEAKENING. THUS WHILE LOWS WILL BE ABOVE
NORMAL...MAY STILL SEE THEM GET DOWN INTO THE LOW TO MID 50S BY
MORNING IN MOST LOCATIONS.
MID LEVEL FRONTAL BOUNDARY LINGERS OVERHEAD TONIGHT INTO
TOMORROW...WITH A WEAK WAVE RIDING OVER THE RIDGE. SO WILL SEE A
REGION OF WEAK LIFT AND DECENT MID LEVEL LAPSE RATES. HOWEVER THETAE
ADVECTION IS PRETTY WEEK...AND LOW LEVELS WILL REMAIN VERY DRY. WILL
PROBABLY SEE SOME ELEVATED CONVECTION FORM ACROSS WESTERN NEBRASKA
AND SOUTH DAKOTA TONIGHT...WHICH WILL TRY TO MOVE EAST TOWARDS OUR
AREA. HOWEVER GIVEN THE ABOVE LIMITATIONS...THINK THE CHANCE OF
MEASURABLE PRECIP IN OUR CWA IS TOO LOW TO MENTION AT THIS TIME.
HOWEVER CAN NOT RULE OUT AN ISOLATED SHOWER OR SOME SPRINKLES
REACHING THE GROUND ANYTIME FROM LATE TONIGHT THROUGH THE DAY
TOMORROW. HIGH TEMPERATURES A BIT TRICKY GIVEN CLOUD COVER
POTENTIAL. BUT FEEL WE WILL SEE PERIODS OF SUN AS WELL...WITH
GENERALLY PARTLY TO AT TIMES MOSTLY SUNNY SKIES. AND RECENTLY WE
HAVE BEEN GETTING WARMER THAN JUST ABOUT EVERY GUIDANCE...SO DESPITE
CLOUD COVER CONCERNS WENT AHEAD AND RAISED HIGHS A COUPLE
DEGREES...GENERALLY IN THE UPPER 70S TO AROUND 80.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 325 PM CDT TUE MAY 14 2013
THE FRONT SOUTH OF THE AREA WILL BEGIN TO MOVE NORTH AS A WARM
FRONT WEDNESDAY NIGHT AND SHOULD BEGIN TO BRING SOME MORE MOIST
AND UNSTABLE AIR INTO THE AREA BY THE END OF THE NIGHT. LOW
TEMEPRATURES SHOULD BE NEAR SEASONAL VALUES BEFORE MOST OF THE
HUMID AIR GETS HERE ON THURSDAY. THE THREAT OF THUNDERSTORMS IN
WARM ADVECTION PATTERN NORTH OF THE FRONT MAY BEGIN IN THE SOUTH
LATE WEDNESDAY NIGHT. THIS THREAT SHOULD GENERALLY BE AROUND FOR
THE REST OF THE FORECAST...ALTHOUGH WILL KEEP POPS MINIMAL ON
FRIDAY AS IT LOOKS LIKE THERE MAY BE A BREAK ON THAT DAY. THEN THE
THREAT WILL INCREASE AGAIN FOR THE WEEKEND AS MAIN UPPER TROUGH
APPROACHES...WITH THE PEAK THREAT SATURDAY NIGHT. A SEVERE THREAT
OR MODESTLY HEAVY RAIN SEEMS POSSIBLE OVER THE WEEKEND.
INSTABILITY AND MOISTURE UNCERTAIN WITH IT BEING WELL DISCUSSED
ABOUT THE TOO HIGH GFS DEW POINTS. IN ANY EVENT TEMPERATURES WILL
BE WARM DURING THE DAY BUT EVEN WARMER RELATIVE TO NORMAL AT
NIGHT...OR NO REAL HOT SPELL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1227 PM CDT TUE MAY 14 2013
VFR CONDITIONS EXPECTED THROUGH THE PERIOD. WINDS GUSTING TO AROUND
30 KTS WILL CONTINUE THROUGH THE DAY...FROM THE SOUTHWEST AHEAD OF AN
APPROACHING COLD FRONT AND THE NORTHWEST BEHIND IT. WINDS WILL
DIMINISH TONIGHT. WILL LIKELY SEE SOME INCREASING MID CLOUDS LATER
TONIGHT INTO TOMORROW. CHANCE OF A FEW SHOWERS OUT OF THESE
CLOUDS...BUT WITH DRY LOW LEVELS DO NOT THINK MUCH OF ANYTHING WILL
REACH THE SURFACE.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR SDZ255>258.
MN...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR MNZ900.
IA...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR IAZ300-301.
NE...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR NEZ249.
&&
$$
SHORT TERM...CHENARD
LONG TERM...
AVIATION...CHENARD
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
212 PM CDT TUE MAY 14 2013
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 211 PM CDT TUE MAY 14 2013
FRONT CONTINUES TO MOVE ACROSS THE CWA THIS AFTERNOON. RECORD HEAT
OUT AHEAD OF THE FRONT WITH LOW TO EVEN MID 100S ACROSS NORTHWEST
IOWA AND PORTIONS OF SOUTHWEST MINNESOTA...AND STILL LOW TO MID 90S
BEHIND THE FRONT ACROSS SOUTHEAST SOUTH DAKOTA. WITH DEWPOINTS
MIXING OUT...NOT MUCH IN THE WAY OF INSTABILITY AHEAD OF THE FRONT.
ALTHOUGH THE HRRR AND RUC HAVE CONTINUED TO SHOW SOME ISOLATED
DEVELOPMENT ALONG THE FRONT BY 22Z. GIVEN THAT BOTH OF THESE SHORT
RANGE MODELS ARE DOING A PRETTY GOOD JOB WITH SURFACE TEMPS AND
DEWPOINTS..THINK SOME ISOLATED CONVECTION MAY FIRE AS WE MIX THROUGH
WHATEVER CAP THERE IS. HOWEVER LOOKS LIKE THIS THREAT IS MAINLY
SOUTH AND SOUTHEAST OF OUR CWA...THUS WILL KEEP THE FORECAST DRY
THROUGH THE EVENING. WEAK COLD AIR ADVECTION CONTINUES THROUGH THE
NIGHT...WITH WINDS WEAKENING. THUS WHILE LOWS WILL BE ABOVE
NORMAL...MAY STILL SEE THEM GET DOWN INTO THE LOW TO MID 50S BY
MORNING IN MOST LOCATIONS.
MID LEVEL FRONTAL BOUNDARY LINGERS OVERHEAD TONIGHT INTO
TOMORROW...WITH A WEAK WAVE RIDING OVER THE RIDGE. SO WILL SEE A
REGION OF WEAK LIFT AND DECENT MID LEVEL LAPSE RATES. HOWEVER THETAE
ADVECTION IS PRETTY WEEK...AND LOW LEVELS WILL REMAIN VERY DRY. WILL
PROBABLY SEE SOME ELEVATED CONVECTION FORM ACROSS WESTERN NEBRASKA
AND SOUTH DAKOTA TONIGHT...WHICH WILL TRY TO MOVE EAST TOWARDS OUR
AREA. HOWEVER GIVEN THE ABOVE LIMITATIONS...THINK THE CHANCE OF
MEASURABLE PRECIP IN OUR CWA IS TOO LOW TO MENTION AT THIS TIME.
HOWEVER CAN NOT RULE OUT AN ISOLATED SHOWER OR SOME SPRINKLES
REACHING THE GROUND ANYTIME FROM LATE TONIGHT THROUGH THE DAY
TOMORROW. HIGH TEMPERATURES A BIT TRICKY GIVEN CLOUD COVER
POTENTIAL. BUT FEEL WE WILL SEE PERIODS OF SUN AS WELL...WITH
GENERALLY PARTLY TO AT TIMES MOSTLY SUNNY SKIES. AND RECENTLY WE
HAVE BEEN GETTING WARMER THAN JUST ABOUT EVERY GUIDANCE...SO DESPITE
CLOUD COVER CONCERNS WENT AHEAD AND RAISED HIGHS A COUPLE
DEGREES...GENERALLY IN THE UPPER 70S TO AROUND 80.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 343 AM CDT TUE MAY 14 2013
SURFACE HIGH PRESSURE BUILDS SOUTHWARD INTO THE REGION ON WEDNESDAY
AND WEDNESDAY NIGHT...PROVIDING FOR PLEASANT CONDITIONS WITH
TEMPERATURES CLOSE TO NORMAL FOR THIS TIME OF YEAR. THIS WILL PLAY
OUT TO HIGHS IN THE MID AND UPPER 70S...WITH LOWS EARLY ON THURSDAY
IN THE UPPER 40S TO LOWER 50S.
THE HIGH MOVES EASTWARD ON THURSDAY WITH A SOUTHERLY FLOW RETURNING
TO OUR AREA ON THE BACKSIDE OF THE HIGH. THINK MOST OF THE DAY WILL
REMAIN DRY WITH WARMING TEMPERATURES...INTO THE UPPER 70S TO AROUND
80 FOR AFTERNOON HIGHS. CANNOT RULE OUT SOME THUNDERSTORM
DEVELOPMENT IN OUR SOUTHWEST LATER IN THE AFTERNOON...WITH A BETTER
CHANCE ON THURSDAY NIGHT AS A WARM FRONT BEGINS TO LIFT THROUGH
NEBRASKA AND 850 MB CONVERGENCE IS ENHANCED AS A LOW LEVEL JET
DEVELOPS THROUGH THE REGION. DOES APPEAR TO BE ENOUGH ELEVATED
CAPE...500 TO 1000 J/KG...AND EFFECTIVE SHEAR OF AROUND 30 KTS IN
THE EVENING THAT CANNOT RULE OUT A COUPLE OF SEVERE STORMS WITH
LARGE HAIL.
A MESSY PATTERN CONTINUES THROUGH THE EXTENDED...FRIDAY INTO MONDAY
OF NEXT WEEK...WITH PERIODIC CHANCES OF CONVECTION THROUGH THE
PERIOD WITH A BOUNDARY MEANDERING AROUND THE AREA AND A SERIES OF
SUBTLE WAVES TRACKING ACROSS THE REGION. HARD TO TIME THIS
CONVECTION DEPENDENT ON WHERE SYNOPTIC/MESOSCALE FEATURES SET
UP...BUT WITH INCREASING LOW LEVEL MOISTURE AND INSTABILITY ACROSS
THE REGION THROUGH THE WEEKEND THERE IS FAIRLY HIGH CONFIDENCE THAT
CONVECTION WILL OCCUR. CONVECTIVE PARAMETERS WOULD ALSO SUGGEST THAT
SEVERE STORMS WILL BE POSSIBLE FOR THOSE DAYS. AN UPPER LEVEL TROUGH
FINALLY SWINGS OUT OF THE WESTERN U.S. ON SUNDAY AND
MONDAY...KEEPING A CHANCE OF CONVECTION ACROSS THE REGION...AS WELL
AS BRINGING A COOLING TREND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1227 PM CDT TUE MAY 14 2013
VFR CONDITIONS EXPECTED THROUGH THE PERIOD. WINDS GUSTING TO AROUND
30 KTS WILL CONTINUE THROUGH THE DAY...FROM THE SOUTHWEST AHEAD OF AN
APPROACHING COLD FRONT AND THE NORTHWEST BEHIND IT. WINDS WILL
DIMINISH TONIGHT. WILL LIKELY SEE SOME INCREASING MID CLOUDS LATER
TONIGHT INTO TOMORROW. CHANCE OF A FEW SHOWERS OUT OF THESE
CLOUDS...BUT WITH DRY LOW LEVELS DO NOT THINK MUCH OF ANYTHING WILL
REACH THE SURFACE.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR SDZ255>258.
MN...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR MNZ900.
IA...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR IAZ300-301.
NE...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR NEZ249.
&&
$$
SHORT TERM...CHENARD
LONG TERM...JM
AVIATION...CHENARD
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1229 PM CDT TUE MAY 14 2013
.UPDATE...
ISSUED AT 1029 AM CDT TUE MAY 14 2013
FORECAST LOOKS IN PRETTY GOOD SHAPE. RED FLAG WARNING LOOKS
GOOD...WITH BLUSTERY SOUTHWEST WINDS AHEAD OF THE COLD
FRONT...TRANSITIONING TO NORTHWEST BEHIND IT. EXPECT FREQUENT GUSTS
INTO THE 25 TO 35 MPH RANGE WITH RELATIVE HUMIDITY DROPPING TO AROUND
20 PERCENT...OR EVEN A LITTLE LOWER AHEAD OF THE FRONT THIS
AFTERNOON. LEADING EDGE OF THE ACCAS IS A SOME SORT OF BOUNDARY WITH
WINDS TURNING MORE WEST SOUTHWESTERLY BEHIND IT. HOWEVER THE TRUE
COLD FRONT IS BEHIND THIS...HAVING JUST GONE THROUGH CHAMBERLAIN AND
HURON WITH THEIR WINDS TURNING NORTHWEST. WENT AHEAD AND RAISED
HIGHS A FEW DEGREES FOR TODAY...WITH READINGS AROUND 100 LOOKING
LIKELY ACROSS NORTHEAST NEBRASKA AND NORTHWEST IOWA...LOCATIONS THAT
WILL STAY JUST AHEAD OF THE COLD FRONT THROUGH THE PEAK OF DAYTIME
HEATING. CONVECTION CHANCES WITH THE FRONT STILL LOOK LOW WITH
DEWPOINTS MIXING OUT. HOWEVER HRRR IS SHOWING SOME ACTIVITY AFTER
21Z. AND GIVEN THAT ITS BOUNDARY LAYER DEPICTION SEEMS DECENT...CAN
NOT COMPLETELY IGNORE THE CHANCE. HOWEVER IT DOES APPEAR THAT THE
BEST CHANCE WILL STAY SOUTH OF OUR CWA ACROSS NEBRASKA...THUS WILL
KEEP THE FORECAST DRY FOR NOW. ALTHOUGH ANY STORM THAT IS ABLE TO
FORM WOULD BE CAPABLE OF POTENTIALLY SEVERE WIND GUSTS GIVEN THE DRY
PROFILES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 343 AM CDT TUE MAY 14 2013
MAIN CHALLENGE FOR TODAY WILL BE WINDS/HUMIDITY LEVELS/ASSOCIATED
FIRE WEATHER CONCERNS IN MIXY ENVIRONMENT AHEAD OF AND BEHIND COOL
FRONT WHICH WILL PUSH SOUTHEAST ACROSS THE REGION THROUGH THE DAY.
LOW LEVEL TEMPERATURES AHEAD OF THE FRONT EASILY SUPPORTIVE OF MID
90S ACROSS MUCH OF NORTHWEST IOWA THIS AFTERNOON...WITH SOME MODELS
SHOWING POTENTIAL FOR HIGHS CLOSER TO OR JUST ABOVE THE CENTURY MARK.
WITH THE STRONG MIXING COMES LIKELIHOOD OF MIXING DRIER AIR ALOFT TO
THE SURFACE. MODELS HAVE BEEN HAVING DIFFICULTY CAPTURING THE DIURNAL
DRYING TREND WITH AFTERNOON MIXING...HANGING ONTO SHALLOW MOISTURE OR
MIXING BOUNDARY LAYER MOISTURE UPWARD RATHER THAN BRINGING DRIER AIR
TO SURFACE AS DEEPER MIXING COMMENCES. RUC SEEMS TO HANDLE IT BETTER
THAN NAM/GFS...AND MORE CLOSELY FOLLOWED THAT IDEA THROUGH THE LATE
MORNING/AFTERNOON...THOUGH NOT QUITE AS DRY AS RUC INDICATES AT THIS
POINT GIVEN EXTREME DISPARITY FROM OTHER MODELS /AS MUCH AS 10-15F
DRIER THAN MOST OTHER GUIDANCE FOR 21Z/. DRIEST AIR SHOULD BE OVER
FAR SOUTHEAST AND WESTERN PARTS OF THE FORECAST AREA DURING PEAK
HEATING...WITH SLIGHT MOISTURE POOLING IN SOMEWHAT LESS MIXY AREA
RIGHT ALONG THE FRONT...FORECAST TO BE JUST EAST OF KYKN-KFSD-KMML
LINE AT 21Z. ALL THIS LEADS TO MINIMUM HUMIDITY LEVELS OF 15-25
PERCENT THIS AFTERNOON... AND THIS ALONG WITH WINDS GUSTING IN THE
25-30KT RANGE STILL SUPPORTIVE OF RED FLAG WARNING WHICH WAS ISSUED
ON THE DAY SHIFT YESTERDAY.
COLD FRONT SETTLES SOUTH OF THE AREA TONIGHT...WITH COOLING
TEMPERATURES AND DYING WINDS OVERNIGHT. LOWS LOOK TO DROP INTO THE
UPPER 40S NORTHWEST...TO MID 50S THROUGH THE LOWER MISSOURI RIVER
VALLEY INTO NORTHWESTERN IOWA.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 343 AM CDT TUE MAY 14 2013
SURFACE HIGH PRESSURE BUILDS SOUTHWARD INTO THE REGION ON WEDNESDAY
AND WEDNESDAY NIGHT...PROVIDING FOR PLEASANT CONDITIONS WITH
TEMPERATURES CLOSE TO NORMAL FOR THIS TIME OF YEAR. THIS WILL PLAY
OUT TO HIGHS IN THE MID AND UPPER 70S...WITH LOWS EARLY ON THURSDAY
IN THE UPPER 40S TO LOWER 50S.
THE HIGH MOVES EASTWARD ON THURSDAY WITH A SOUTHERLY FLOW RETURNING
TO OUR AREA ON THE BACKSIDE OF THE HIGH. THINK MOST OF THE DAY WILL
REMAIN DRY WITH WARMING TEMPERATURES...INTO THE UPPER 70S TO AROUND
80 FOR AFTERNOON HIGHS. CANNOT RULE OUT SOME THUNDERSTORM
DEVELOPMENT IN OUR SOUTHWEST LATER IN THE AFTERNOON...WITH A BETTER
CHANCE ON THURSDAY NIGHT AS A WARM FRONT BEGINS TO LIFT THROUGH
NEBRASKA AND 850 MB CONVERGENCE IS ENHANCED AS A LOW LEVEL JET
DEVELOPS THROUGH THE REGION. DOES APPEAR TO BE ENOUGH ELEVATED
CAPE...500 TO 1000 J/KG...AND EFFECTIVE SHEAR OF AROUND 30 KTS IN
THE EVENING THAT CANNOT RULE OUT A COUPLE OF SEVERE STORMS WITH
LARGE HAIL.
A MESSY PATTERN CONTINUES THROUGH THE EXTENDED...FRIDAY INTO MONDAY
OF NEXT WEEK...WITH PERIODIC CHANCES OF CONVECTION THROUGH THE
PERIOD WITH A BOUNDARY MEANDERING AROUND THE AREA AND A SERIES OF
SUBTLE WAVES TRACKING ACROSS THE REGION. HARD TO TIME THIS
CONVECTION DEPENDENT ON WHERE SYNOPTIC/MESOSCALE FEATURES SET
UP...BUT WITH INCREASING LOW LEVEL MOISTURE AND INSTABILITY ACROSS
THE REGION THROUGH THE WEEKEND THERE IS FAIRLY HIGH CONFIDENCE THAT
CONVECTION WILL OCCUR. CONVECTIVE PARAMETERS WOULD ALSO SUGGEST THAT
SEVERE STORMS WILL BE POSSIBLE FOR THOSE DAYS. AN UPPER LEVEL TROUGH
FINALLY SWINGS OUT OF THE WESTERN U.S. ON SUNDAY AND
MONDAY...KEEPING A CHANCE OF CONVECTION ACROSS THE REGION...AS WELL
AS BRINGING A COOLING TREND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1227 PM CDT TUE MAY 14 2013
VFR CONDITIONS EXPECTED THROUGH THE PERIOD. WINDS GUSTING TO AROUND
30 KTS WILL CONTINUE THROUGH THE DAY...FROM THE SOUTHWEST AHEAD OF AN
APPROACHING COLD FRONT AND THE NORTHWEST BEHIND IT. WINDS WILL
DIMINISH TONIGHT. WILL LIKELY SEE SOME INCREASING MID CLOUDS LATER
TONIGHT INTO TOMORROW. CHANCE OF A FEW SHOWERS OUT OF THESE
CLOUDS...BUT WITH DRY LOW LEVELS DO NOT THINK MUCH OF ANYTHING WILL
REACH THE SURFACE.
&&
.FIRE WEATHER...
ISSUED AT 343 AM CDT TUE MAY 14 2013
RED FLAG WARNING STILL LOOKS WARRANTED FOR THE AFTERNOON AND EARLY
EVENING. GUSTY SOUTHWEST WINDS OF 25 TO 35 MPH AHEAD OF COOL FRONT
WILL SWITCH TO NORTHWEST BEHIND THE FRONT AND REMAIN AS STRONG. ALONG
WITH THE GUSTY WINDS WILL BE DRY RELATIVE HUMIDITY LEVELS IN THE 15
TO 25 PERCENT RANGE...AS DRY AND UNSEASONABLY WARM AIR ALOFT MIXES TO
THE SURFACE. AREAS RIGHT ALONG THE FRONT MAY NOT SEE AS SUSTAINED A
PERIOD OF RED FLAG CRITERIA DUE TO MOISTURE POOLING AND LIGHTER/LESS
GUSTY WINDS WITHIN THE FRONTAL ZONE...BUT SHOULD STILL REACH CRITERIA
AT TIMES. RECENT GREENING OF COOL SEASON GRASSES MAY SLOW FIRE STARTS
ACROSS THE AREA...BUT ANY FIRES THAT DO IGNITE WILL SPREAD VERY
QUICKLY IN THE LINGERING DORMANT TALL GRASSES.
SOME MODELS ALSO INDICATE POTENTIAL FOR EVEN WARMER/DRIER AIR MIXING
TO THE SURFACE AHEAD OF THE FRONT...MAINLY IN NORTHWEST IOWA THIS
AFTERNOON...SO THIS WILL BE WATCHED CLOSELY THROUGHOUT THE DAY.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR SDZ255>258.
MN...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR MNZ900.
IA...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR IAZ300-301.
NE...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR NEZ249.
&&
$$
UPDATE...CHENARD
SHORT TERM...JH/JM
LONG TERM...JM
AVIATION...CHENARD
FIRE WEATHER...JH
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1038 AM CDT TUE MAY 14 2013
.UPDATE...
ISSUED AT 1029 AM CDT TUE MAY 14 2013
FORECAST LOOKS IN PRETTY GOOD SHAPE. RED FLAG WARNING LOOKS
GOOD...WITH BLUSTERY SOUTHWEST WINDS AHEAD OF THE COLD
FRONT...TRANSITIONING TO NORTHWEST BEHIND IT. EXPECT FREQUENT GUSTS
INTO THE 25 TO 35 MPH RANGE WITH RELATIVE HUMIDITY DROPPING TO AROUND
20 PERCENT...OR EVEN A LITTLE LOWER AHEAD OF THE FRONT THIS
AFTERNOON. LEADING EDGE OF THE ACCAS IS A SOME SORT OF BOUNDARY WITH
WINDS TURNING MORE WEST SOUTHWESTERLY BEHIND IT. HOWEVER THE TRUE
COLD FRONT IS BEHIND THIS...HAVING JUST GONE THROUGH CHAMBERLAIN AND
HURON WITH THEIR WINDS TURNING NORTHWEST. WENT AHEAD AND RAISED
HIGHS A FEW DEGREES FOR TODAY...WITH READINGS AROUND 100 LOOKING
LIKELY ACROSS NORTHEAST NEBRASKA AND NORTHWEST IOWA...LOCATIONS THAT
WILL STAY JUST AHEAD OF THE COLD FRONT THROUGH THE PEAK OF DAYTIME
HEATING. CONVECTION CHANCES WITH THE FRONT STILL LOOK LOW WITH
DEWPOINTS MIXING OUT. HOWEVER HRRR IS SHOWING SOME ACTIVITY AFTER
21Z. AND GIVEN THAT ITS BOUNDARY LAYER DEPICTION SEEMS DECENT...CAN
NOT COMPLETELY IGNORE THE CHANCE. HOWEVER IT DOES APPEAR THAT THE
BEST CHANCE WILL STAY SOUTH OF OUR CWA ACROSS NEBRASKA...THUS WILL
KEEP THE FORECAST DRY FOR NOW. ALTHOUGH ANY STORM THAT IS ABLE TO
FORM WOULD BE CAPABLE OF POTENTIALLY SEVERE WIND GUSTS GIVEN THE DRY
PROFILES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 343 AM CDT TUE MAY 14 2013
MAIN CHALLENGE FOR TODAY WILL BE WINDS/HUMIDITY LEVELS/ASSOCIATED
FIRE WEATHER CONCERNS IN MIXY ENVIRONMENT AHEAD OF AND BEHIND COOL
FRONT WHICH WILL PUSH SOUTHEAST ACROSS THE REGION THROUGH THE DAY.
LOW LEVEL TEMPERATURES AHEAD OF THE FRONT EASILY SUPPORTIVE OF MID
90S ACROSS MUCH OF NORTHWEST IOWA THIS AFTERNOON...WITH SOME MODELS
SHOWING POTENTIAL FOR HIGHS CLOSER TO OR JUST ABOVE THE CENTURY MARK.
WITH THE STRONG MIXING COMES LIKELIHOOD OF MIXING DRIER AIR ALOFT TO
THE SURFACE. MODELS HAVE BEEN HAVING DIFFICULTY CAPTURING THE DIURNAL
DRYING TREND WITH AFTERNOON MIXING...HANGING ONTO SHALLOW MOISTURE OR
MIXING BOUNDARY LAYER MOISTURE UPWARD RATHER THAN BRINGING DRIER AIR
TO SURFACE AS DEEPER MIXING COMMENCES. RUC SEEMS TO HANDLE IT BETTER
THAN NAM/GFS...AND MORE CLOSELY FOLLOWED THAT IDEA THROUGH THE LATE
MORNING/AFTERNOON...THOUGH NOT QUITE AS DRY AS RUC INDICATES AT THIS
POINT GIVEN EXTREME DISPARITY FROM OTHER MODELS /AS MUCH AS 10-15F
DRIER THAN MOST OTHER GUIDANCE FOR 21Z/. DRIEST AIR SHOULD BE OVER
FAR SOUTHEAST AND WESTERN PARTS OF THE FORECAST AREA DURING PEAK
HEATING...WITH SLIGHT MOISTURE POOLING IN SOMEWHAT LESS MIXY AREA
RIGHT ALONG THE FRONT...FORECAST TO BE JUST EAST OF KYKN-KFSD-KMML
LINE AT 21Z. ALL THIS LEADS TO MINIMUM HUMIDITY LEVELS OF 15-25
PERCENT THIS AFTERNOON... AND THIS ALONG WITH WINDS GUSTING IN THE
25-30KT RANGE STILL SUPPORTIVE OF RED FLAG WARNING WHICH WAS ISSUED
ON THE DAY SHIFT YESTERDAY.
COLD FRONT SETTLES SOUTH OF THE AREA TONIGHT...WITH COOLING
TEMPERATURES AND DYING WINDS OVERNIGHT. LOWS LOOK TO DROP INTO THE
UPPER 40S NORTHWEST...TO MID 50S THROUGH THE LOWER MISSOURI RIVER
VALLEY INTO NORTHWESTERN IOWA.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 343 AM CDT TUE MAY 14 2013
SURFACE HIGH PRESSURE BUILDS SOUTHWARD INTO THE REGION ON WEDNESDAY
AND WEDNESDAY NIGHT...PROVIDING FOR PLEASANT CONDITIONS WITH
TEMPERATURES CLOSE TO NORMAL FOR THIS TIME OF YEAR. THIS WILL PLAY
OUT TO HIGHS IN THE MID AND UPPER 70S...WITH LOWS EARLY ON THURSDAY
IN THE UPPER 40S TO LOWER 50S.
THE HIGH MOVES EASTWARD ON THURSDAY WITH A SOUTHERLY FLOW RETURNING
TO OUR AREA ON THE BACKSIDE OF THE HIGH. THINK MOST OF THE DAY WILL
REMAIN DRY WITH WARMING TEMPERATURES...INTO THE UPPER 70S TO AROUND
80 FOR AFTERNOON HIGHS. CANNOT RULE OUT SOME THUNDERSTORM
DEVELOPMENT IN OUR SOUTHWEST LATER IN THE AFTERNOON...WITH A BETTER
CHANCE ON THURSDAY NIGHT AS A WARM FRONT BEGINS TO LIFT THROUGH
NEBRASKA AND 850 MB CONVERGENCE IS ENHANCED AS A LOW LEVEL JET
DEVELOPS THROUGH THE REGION. DOES APPEAR TO BE ENOUGH ELEVATED
CAPE...500 TO 1000 J/KG...AND EFFECTIVE SHEAR OF AROUND 30 KTS IN
THE EVENING THAT CANNOT RULE OUT A COUPLE OF SEVERE STORMS WITH
LARGE HAIL.
A MESSY PATTERN CONTINUES THROUGH THE EXTENDED...FRIDAY INTO MONDAY
OF NEXT WEEK...WITH PERIODIC CHANCES OF CONVECTION THROUGH THE
PERIOD WITH A BOUNDARY MEANDERING AROUND THE AREA AND A SERIES OF
SUBTLE WAVES TRACKING ACROSS THE REGION. HARD TO TIME THIS
CONVECTION DEPENDENT ON WHERE SYNOPTIC/MESOSCALE FEATURES SET
UP...BUT WITH INCREASING LOW LEVEL MOISTURE AND INSTABILITY ACROSS
THE REGION THROUGH THE WEEKEND THERE IS FAIRLY HIGH CONFIDENCE THAT
CONVECTION WILL OCCUR. CONVECTIVE PARAMETERS WOULD ALSO SUGGEST THAT
SEVERE STORMS WILL BE POSSIBLE FOR THOSE DAYS. AN UPPER LEVEL TROUGH
FINALLY SWINGS OUT OF THE WESTERN U.S. ON SUNDAY AND
MONDAY...KEEPING A CHANCE OF CONVECTION ACROSS THE REGION...AS WELL
AS BRINGING A COOLING TREND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 634 AM CDT TUE MAY 14 2013
MAIN AVIATION CONCERN TODAY WILL BE GUSTY WINDS...FIRST OUT OF THE
SOUTHWEST BY 14Z AHEAD OF APPROACHING COLD FRONT...WITH THE WINDS
BECOMING NORTHWEST AS THE FRONT PROGRESSES SOUTHEAST ACROSS THE
FORECAST AREA THROUGH THE DAY. GUSTY WINDS WILL SUBSIDE WITH SUNSET
AROUND 15/01Z. VFR CONDITIONS THROUGH THE PERIOD.
&&
.FIRE WEATHER...
ISSUED AT 343 AM CDT TUE MAY 14 2013
RED FLAG WARNING STILL LOOKS WARRANTED FOR THE AFTERNOON AND EARLY
EVENING. GUSTY SOUTHWEST WINDS OF 25 TO 35 MPH AHEAD OF COOL FRONT
WILL SWITCH TO NORTHWEST BEHIND THE FRONT AND REMAIN AS STRONG. ALONG
WITH THE GUSTY WINDS WILL BE DRY RELATIVE HUMIDITY LEVELS IN THE 15
TO 25 PERCENT RANGE...AS DRY AND UNSEASONABLY WARM AIR ALOFT MIXES TO
THE SURFACE. AREAS RIGHT ALONG THE FRONT MAY NOT SEE AS SUSTAINED A
PERIOD OF RED FLAG CRITERIA DUE TO MOISTURE POOLING AND LIGHTER/LESS
GUSTY WINDS WITHIN THE FRONTAL ZONE...BUT SHOULD STILL REACH CRITERIA
AT TIMES. RECENT GREENING OF COOL SEASON GRASSES MAY SLOW FIRE STARTS
ACROSS THE AREA...BUT ANY FIRES THAT DO IGNITE WILL SPREAD VERY
QUICKLY IN THE LINGERING DORMANT TALL GRASSES.
SOME MODELS ALSO INDICATE POTENTIAL FOR EVEN WARMER/DRIER AIR MIXING
TO THE SURFACE AHEAD OF THE FRONT...MAINLY IN NORTHWEST IOWA THIS
AFTERNOON...SO THIS WILL BE WATCHED CLOSELY THROUGHOUT THE DAY.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR SDZ255>258.
MN...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR MNZ900.
IA...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR IAZ300-301.
NE...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR NEZ249.
&&
$$
UPDATE...CHENARD
SHORT TERM...JH/JM
LONG TERM...JM
AVIATION...JH
FIRE WEATHER...JH
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
634 AM CDT TUE MAY 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 343 AM CDT TUE MAY 14 2013
MAIN CHALLENGE FOR TODAY WILL BE WINDS/HUMIDITY LEVELS/ASSOCIATED
FIRE WEATHER CONCERNS IN MIXY ENVIRONMENT AHEAD OF AND BEHIND COOL
FRONT WHICH WILL PUSH SOUTHEAST ACROSS THE REGION THROUGH THE DAY.
LOW LEVEL TEMPERATURES AHEAD OF THE FRONT EASILY SUPPORTIVE OF MID
90S ACROSS MUCH OF NORTHWEST IOWA THIS AFTERNOON...WITH SOME MODELS
SHOWING POTENTIAL FOR HIGHS CLOSER TO OR JUST ABOVE THE CENTURY MARK.
WITH THE STRONG MIXING COMES LIKELIHOOD OF MIXING DRIER AIR ALOFT TO
THE SURFACE. MODELS HAVE BEEN HAVING DIFFICULTY CAPTURING THE DIURNAL
DRYING TREND WITH AFTERNOON MIXING...HANGING ONTO SHALLOW MOISTURE OR
MIXING BOUNDARY LAYER MOISTURE UPWARD RATHER THAN BRINGING DRIER AIR
TO SURFACE AS DEEPER MIXING COMMENCES. RUC SEEMS TO HANDLE IT BETTER
THAN NAM/GFS...AND MORE CLOSELY FOLLOWED THAT IDEA THROUGH THE LATE
MORNING/AFTERNOON...THOUGH NOT QUITE AS DRY AS RUC INDICATES AT THIS
POINT GIVEN EXTREME DISPARITY FROM OTHER MODELS /AS MUCH AS 10-15F
DRIER THAN MOST OTHER GUIDANCE FOR 21Z/. DRIEST AIR SHOULD BE OVER
FAR SOUTHEAST AND WESTERN PARTS OF THE FORECAST AREA DURING PEAK
HEATING...WITH SLIGHT MOISTURE POOLING IN SOMEWHAT LESS MIXY AREA
RIGHT ALONG THE FRONT...FORECAST TO BE JUST EAST OF KYKN-KFSD-KMML
LINE AT 21Z. ALL THIS LEADS TO MINIMUM HUMIDITY LEVELS OF 15-25
PERCENT THIS AFTERNOON... AND THIS ALONG WITH WINDS GUSTING IN THE
25-30KT RANGE STILL SUPPORTIVE OF RED FLAG WARNING WHICH WAS ISSUED
ON THE DAY SHIFT YESTERDAY.
COLD FRONT SETTLES SOUTH OF THE AREA TONIGHT...WITH COOLING
TEMPERATURES AND DYING WINDS OVERNIGHT. LOWS LOOK TO DROP INTO THE
UPPER 40S NORTHWEST...TO MID 50S THROUGH THE LOWER MISSOURI RIVER
VALLEY INTO NORTHWESTERN IOWA.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 343 AM CDT TUE MAY 14 2013
SURFACE HIGH PRESSURE BUILDS SOUTHWARD INTO THE REGION ON WEDNESDAY
AND WEDNESDAY NIGHT...PROVIDING FOR PLEASANT CONDITIONS WITH
TEMPERATURES CLOSE TO NORMAL FOR THIS TIME OF YEAR. THIS WILL PLAY
OUT TO HIGHS IN THE MID AND UPPER 70S...WITH LOWS EARLY ON THURSDAY
IN THE UPPER 40S TO LOWER 50S.
THE HIGH MOVES EASTWARD ON THURSDAY WITH A SOUTHERLY FLOW RETURNING
TO OUR AREA ON THE BACKSIDE OF THE HIGH. THINK MOST OF THE DAY WILL
REMAIN DRY WITH WARMING TEMPERATURES...INTO THE UPPER 70S TO AROUND
80 FOR AFTERNOON HIGHS. CANNOT RULE OUT SOME THUNDERSTORM
DEVELOPMENT IN OUR SOUTHWEST LATER IN THE AFTERNOON...WITH A BETTER
CHANCE ON THURSDAY NIGHT AS A WARM FRONT BEGINS TO LIFT THROUGH
NEBRASKA AND 850 MB CONVERGENCE IS ENHANCED AS A LOW LEVEL JET
DEVELOPS THROUGH THE REGION. DOES APPEAR TO BE ENOUGH ELEVATED
CAPE...500 TO 1000 J/KG...AND EFFECTIVE SHEAR OF AROUND 30 KTS IN
THE EVENING THAT CANNOT RULE OUT A COUPLE OF SEVERE STORMS WITH
LARGE HAIL.
A MESSY PATTERN CONTINUES THROUGH THE EXTENDED...FRIDAY INTO MONDAY
OF NEXT WEEK...WITH PERIODIC CHANCES OF CONVECTION THROUGH THE
PERIOD WITH A BOUNDARY MEANDERING AROUND THE AREA AND A SERIES OF
SUBTLE WAVES TRACKING ACROSS THE REGION. HARD TO TIME THIS
CONVECTION DEPENDENT ON WHERE SYNOPTIC/MESOSCALE FEATURES SET
UP...BUT WITH INCREASING LOW LEVEL MOISTURE AND INSTABILITY ACROSS
THE REGION THROUGH THE WEEKEND THERE IS FAIRLY HIGH CONFIDENCE THAT
CONVECTION WILL OCCUR. CONVECTIVE PARAMETERS WOULD ALSO SUGGEST THAT
SEVERE STORMS WILL BE POSSIBLE FOR THOSE DAYS. AN UPPER LEVEL TROUGH
FINALLY SWINGS OUT OF THE WESTERN U.S. ON SUNDAY AND
MONDAY...KEEPING A CHANCE OF CONVECTION ACROSS THE REGION...AS WELL
AS BRINGING A COOLING TREND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 634 AM CDT TUE MAY 14 2013
MAIN AVIATION CONCERN TODAY WILL BE GUSTY WINDS...FIRST OUT OF THE
SOUTHWEST BY 14Z AHEAD OF APPROACHING COLD FRONT...WITH THE WINDS
BECOMING NORTHWEST AS THE FRONT PROGRESSES SOUTHEAST ACROSS THE
FORECAST AREA THROUGH THE DAY. GUSTY WINDS WILL SUBSIDE WITH SUNSET
AROUND 15/01Z. VFR CONDITIONS THROUGH THE PERIOD.
&&
.FIRE WEATHER...
ISSUED AT 343 AM CDT TUE MAY 14 2013
RED FLAG WARNING STILL LOOKS WARRANTED FOR THE AFTERNOON AND EARLY
EVENING. GUSTY SOUTHWEST WINDS OF 25 TO 35 MPH AHEAD OF COOL FRONT
WILL SWITCH TO NORTHWEST BEHIND THE FRONT AND REMAIN AS STRONG. ALONG
WITH THE GUSTY WINDS WILL BE DRY RELATIVE HUMIDITY LEVELS IN THE 15
TO 25 PERCENT RANGE...AS DRY AND UNSEASONABLY WARM AIR ALOFT MIXES TO
THE SURFACE. AREAS RIGHT ALONG THE FRONT MAY NOT SEE AS SUSTAINED A
PERIOD OF RED FLAG CRITERIA DUE TO MOISTURE POOLING AND LIGHTER/LESS
GUSTY WINDS WITHIN THE FRONTAL ZONE...BUT SHOULD STILL REACH CRITERIA
AT TIMES. RECENT GREENING OF COOL SEASON GRASSES MAY SLOW FIRE STARTS
ACROSS THE AREA...BUT ANY FIRES THAT DO IGNITE WILL SPREAD VERY
QUICKLY IN THE LINGERING DORMANT TALL GRASSES.
SOME MODELS ALSO INDICATE POTENTIAL FOR EVEN WARMER/DRIER AIR MIXING
TO THE SURFACE AHEAD OF THE FRONT...MAINLY IN NORTHWEST IOWA THIS
AFTERNOON...SO THIS WILL BE WATCHED CLOSELY THROUGHOUT THE DAY.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...RED FLAG WARNING FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR
SDZ255>258.
MN...RED FLAG WARNING FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR
MNZ900.
IA...RED FLAG WARNING FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR
IAZ300-301.
NE...RED FLAG WARNING FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR
NEZ249.
&&
$$
SHORT TERM...JH/JM
LONG TERM...JM
AVIATION...JH
FIRE WEATHER...JH
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
343 AM CDT TUE MAY 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 343 AM CDT TUE MAY 14 2013
MAIN CHALLENGE FOR TODAY WILL BE WINDS/HUMIDITY LEVELS/ASSOCIATED
FIRE WEATHER CONCERNS IN MIXY ENVIRONMENT AHEAD OF AND BEHIND COOL
FRONT WHICH WILL PUSH SOUTHEAST ACROSS THE REGION THROUGH THE DAY.
LOW LEVEL TEMPERATURES AHEAD OF THE FRONT EASILY SUPPORTIVE OF MID
90S ACROSS MUCH OF NORTHWEST IOWA THIS AFTERNOON...WITH SOME MODELS
SHOWING POTENTIAL FOR HIGHS CLOSER TO OR JUST ABOVE THE CENTURY MARK.
WITH THE STRONG MIXING COMES LIKELIHOOD OF MIXING DRIER AIR ALOFT TO
THE SURFACE. MODELS HAVE BEEN HAVING DIFFICULTY CAPTURING THE DIURNAL
DRYING TREND WITH AFTERNOON MIXING...HANGING ONTO SHALLOW MOISTURE OR
MIXING BOUNDARY LAYER MOISTURE UPWARD RATHER THAN BRINGING DRIER AIR
TO SURFACE AS DEEPER MIXING COMMENCES. RUC SEEMS TO HANDLE IT BETTER
THAN NAM/GFS...AND MORE CLOSELY FOLLOWED THAT IDEA THROUGH THE LATE
MORNING/AFTERNOON...THOUGH NOT QUITE AS DRY AS RUC INDICATES AT THIS
POINT GIVEN EXTREME DISPARITY FROM OTHER MODELS /AS MUCH AS 10-15F
DRIER THAN MOST OTHER GUIDANCE FOR 21Z/. DRIEST AIR SHOULD BE OVER
FAR SOUTHEAST AND WESTERN PARTS OF THE FORECAST AREA DURING PEAK
HEATING...WITH SLIGHT MOISTURE POOLING IN SOMEWHAT LESS MIXY AREA
RIGHT ALONG THE FRONT...FORECAST TO BE JUST EAST OF KYKN-KFSD-KMML
LINE AT 21Z. ALL THIS LEADS TO MINIMUM HUMIDITY LEVELS OF 15-25
PERCENT THIS AFTERNOON... AND THIS ALONG WITH WINDS GUSTING IN THE
25-30KT RANGE STILL SUPPORTIVE OF RED FLAG WARNING WHICH WAS ISSUED
ON THE DAY SHIFT YESTERDAY.
COLD FRONT SETTLES SOUTH OF THE AREA TONIGHT...WITH COOLING
TEMPERATURES AND DYING WINDS OVERNIGHT. LOWS LOOK TO DROP INTO THE
UPPER 40S NORTHWEST...TO MID 50S THROUGH THE LOWER MISSOURI RIVER
VALLEY INTO NORTHWESTERN IOWA.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 343 AM CDT TUE MAY 14 2013
SURFACE HIGH PRESSURE BUILDS SOUTHWARD INTO THE REGION ON WEDNESDAY
AND WEDNESDAY NIGHT...PROVIDING FOR PLEASANT CONDITIONS WITH
TEMPERATURES CLOSE TO NORMAL FOR THIS TIME OF YEAR. THIS WILL PLAY
OUT TO HIGHS IN THE MID AND UPPER 70S...WITH LOWS EARLY ON THURSDAY
IN THE UPPER 40S TO LOWER 50S.
THE HIGH MOVES EASTWARD ON THURSDAY WITH A SOUTHERLY FLOW RETURNING
TO OUR AREA ON THE BACKSIDE OF THE HIGH. THINK MOST OF THE DAY WILL
REMAIN DRY WITH WARMING TEMPERATURES...INTO THE UPPER 70S TO AROUND
80 FOR AFTERNOON HIGHS. CANNOT RULE OUT SOME THUNDERSTORM
DEVELOPMENT IN OUR SOUTHWEST LATER IN THE AFTERNOON...WITH A BETTER
CHANCE ON THURSDAY NIGHT AS A WARM FRONT BEGINS TO LIFT THROUGH
NEBRASKA AND 850 MB CONVERGENCE IS ENHANCED AS A LOW LEVEL JET
DEVELOPS THROUGH THE REGION. DOES APPEAR TO BE ENOUGH ELEVATED
CAPE...500 TO 1000 J/KG...AND EFFECTIVE SHEAR OF AROUND 30 KTS IN
THE EVENING THAT CANNOT RULE OUT A COUPLE OF SEVERE STORMS WITH
LARGE HAIL.
A MESSY PATTERN CONTINUES THROUGH THE EXTENDED...FRIDAY INTO MONDAY
OF NEXT WEEK...WITH PERIODIC CHANCES OF CONVECTION THROUGH THE
PERIOD WITH A BOUNDARY MEANDERING AROUND THE AREA AND A SERIES OF
SUBTLE WAVES TRACKING ACROSS THE REGION. HARD TO TIME THIS
CONVECTION DEPENDENT ON WHERE SYNOPTIC/MESOSCALE FEATURES SET
UP...BUT WITH INCREASING LOW LEVEL MOISTURE AND INSTABILITY ACROSS
THE REGION THROUGH THE WEEKEND THERE IS FAIRLY HIGH CONFIDENCE THAT
CONVECTION WILL OCCUR. CONVECTIVE PARAMETERS WOULD ALSO SUGGEST THAT
SEVERE STORMS WILL BE POSSIBLE FOR THOSE DAYS. AN UPPER LEVEL TROUGH
FINALLY SWINGS OUT OF THE WESTERN U.S. ON SUNDAY AND
MONDAY...KEEPING A CHANCE OF CONVECTION ACROSS THE REGION...AS WELL
AS BRINGING A COOLING TREND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1045 PM CDT MON MAY 13 2013
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. LIGHT WESTERLY
FLOW SHOULD GRADUALLY BECOME MORE SOUTHERLY THROUGH THE OVERNIGHT.
GUSTY CONDITIONS WILL RETURN 14-15 Z WITH WINDS SHIFTING TO THE
NORTHWEST THROUGHOUT THE DAY TUESDAY AS A COLD FRONT MOVES
THROUGH. THE GUSTY CONDITIONS SHOULD SUBSIDE WITH SUNSET.
&&
.FIRE WEATHER...
ISSUED AT 343 AM CDT TUE MAY 14 2013
RED FLAG WARNING STILL LOOKS WARRANTED FOR THE AFTERNOON AND EARLY
EVENING. GUSTY SOUTHWEST WINDS OF 25 TO 35 MPH AHEAD OF COOL FRONT
WILL SWITCH TO NORTHWEST BEHIND THE FRONT AND REMAIN AS STRONG. ALONG
WITH THE GUSTY WINDS WILL BE DRY RELATIVE HUMIDITY LEVELS IN THE 15
TO 25 PERCENT RANGE...AS DRY AND UNSEASONABLY WARM AIR ALOFT MIXES TO
THE SURFACE. AREAS RIGHT ALONG THE FRONT MAY NOT SEE AS SUSTAINED A
PERIOD OF RED FLAG CRITERIA DUE TO MOISTURE POOLING AND LIGHTER/LESS
GUSTY WINDS WITHIN THE FRONTAL ZONE...BUT SHOULD STILL REACH CRITERIA
AT TIMES. RECENT GREENING OF COOL SEASON GRASSES MAY SLOW FIRE STARTS
ACROSS THE AREA...BUT ANY FIRES THAT DO IGNITE WILL SPREAD VERY
QUICKLY IN THE LINGERING DORMANT TALL GRASSES.
SOME MODELS ALSO INDICATE POTENTIAL FOR EVEN WARMER/DRIER AIR MIXING
TO THE SURFACE AHEAD OF THE FRONT...MAINLY IN NORTHWEST IOWA THIS
AFTERNOON...SO THIS WILL BE WATCHED CLOSELY THROUGHOUT THE DAY.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...RED FLAG WARNING FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR
SDZ255>258.
MN...RED FLAG WARNING FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR
MNZ900.
IA...RED FLAG WARNING FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR
IAZ300-301.
NE...RED FLAG WARNING FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR
NEZ249.
&&
$$
SHORT TERM...JH/JM
LONG TERM...JM
AVIATION...
FIRE WEATHER...JH
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
934 PM CDT WED MAY 15 2013
.UPDATE...
EVENING FORECAST UPDATE.
&&
.DISCUSSION...
MONITORING SEVERE WEATHER OUTBREAK OVER N C TX WITH GREAT
INTEREST. UNFORTUNATELY SAD THAT THERE HAS BEEN SIGNIFICANT
DAMAMGE IN AREAS SW OF DFW METROPLEX. MAIN CONCERN IS THAT THE 12Z
WRF-ARW AND RECENT RUNS OF HRRR TRY TO BRING A LINE OF STORMS INTO
THE NORTHERN PORTIONS OF SE TX LATE TONIGHT INTO TOMORROW MORNING.
FOR NOW DO NOT SEE A LINE OF STORMS FORMING YET AND WILL WATCH FOR
THIS TO HAPPEN. THINK 30 POPS FOR NOW LOOKS ON TRACK FOR NOW.
ENVIRONMENT IS A LOT LESS FAVORABLE FOR SEVERE WEATHER WITH MOST
OF THE AREA CAPPED AND WITH LESS THAN 1000 J/KG OF CAPE. SUSPECT
THAT STORMS WILL WEAKEN AS THEY MOVE TOWARDS SE TX. THAT IS IF A
LINE OF STORMS CAN FORM WHICH GIVEN THE STORM MODE OF ISO
SUPERCELLS...NOT SURE THAT WILL HAPPEN. RIGHT NOW AREAS FROM
COLLEGE STATION TO CROCKETT ARE ON THE EDGE OF BETTER SUPERCELL
ENVIRONMENT BUT IT IS A FINE LINE. POSSIBLE SPC MAY WATCH THESE
AREAS LATER THIS EVENING BUT REMAINS TO BE SEEN SINCE THE STORM
ENVIRONMENT IS NOT AS FAVORABLE. UPDATED FORECAST HAS BEEN SENT.
39
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 68 85 71 89 72 / 30 10 10 10 10
HOUSTON (IAH) 69 84 71 88 71 / 20 10 10 10 10
GALVESTON (GLS) 72 79 73 78 74 / 20 10 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 4 AM CDT THURSDAY FOR
THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA
SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
TO FREEPORT 20 TO 60 NM.
&&
$$
DISCUSSION...39
AREA FORECAST DISCUSSION
NWS BROWNSVILLE TX
155 PM CDT TUE MAY 14 2013
.SHORT TERM.../TONIGHT THROUGH WEDNESDAY NIGHT/...EVEN THOUGH THE
LATEST RUC13 MODEL RUNS CONTINUE TO SHOW SHOWERS DEVELOPING
ACROSS THE CWA THIS AFTERNOON...RADAR AND SATELLITE IMAGES INDICATE
NOT MUCH IN THE WAY OF RAIN DEVELOPING AS OF YET. SURFACE
INSTABILITY IS MARGINAL ACROSS THE RIO GRANDE VALLEY AND THE CLOUD
COVER MAY BE INHIBITING THE INSTABILITY. IN ADDITION...WATER VAPOR
SAT IMAGES AND NAM80 500MB VORTICITY ANALYSIS INDICATE NEGATIVE VORT
CENTER JUST TO THE WEST OF THE AREA. CURRENT FORECAST THINKING IS
THAT AS THE 500MB LOW ACROSS NORTHWEST MEXICO IS KICKED EASTWARD
WITH THE SHORTWAVE TROUGH MOVING INTO SOUTHERN CALIFORNIA...SHOWERS
AND THUNDERSTORMS WILL DEVELOP LATER THIS AFTERNOON INTO THIS
EVENING ACROSS THE MEXICAN PLATEAU AND MOVE EASTWARD INTO THE
WESTERN PORTIONS OF THE CWA TONIGHT INTO EARLY WEDNESDAY. WITH THAT
SAID...WILL ADJUST TIMING OF POPS TONIGHT INTO WED NIGHT AND KEEP AT
LEAST A CHANCE OF RAIN ACROSS MOST OF THE AREA THROUGH WED
AFTERNOON. RAIN CHANCES SHOULD DIMINISH WED AFTERNOON INTO WED
EVENING AS SUBSIDENCE WILL INCREASE ACROSS SOUTHWEST TX AS THE UPPER
LEVEL LOW MOVES ACROSS NORTHWEST TX WEDNESDAY.
.LONG TERM.../THURSDAY THROUGH TUESDAY NIGHT/...
LOW PRESSURE SYSTEM OVER BAJA CA WILL QUICKLY MOVE ACROSS SOUTH
CENTRAL TEXAS WED INTO THU WITH SURFACE HIGH PRESSURE TO THE EAST
MOVING SOUTHWARD OVER THE GULF WATERS AS IT INTERACTS WITH THE LOW
PRESSURE OVER WEST TEXAS. AS THIS SYSTEM LIFTS TO THE NORTHEAST...
THE SURFACE WINDS WILL RETURN TO THE SOUTHEAST ACROSS SOUTH TEXAS
AND THE GRADIENT IN RETURN WILL STRENGTHEN. EXPECT BREEZE CONDITIONS
BETWEEN 20 TO 25 MPH THURSDAY AFTERNOON. MOST OF THE MOISTURE SEEN
IN THE LAST FEW DAYS WILL DROP DRAMATICALLY ACROSS THE AREA WITH THE
BUFF SOUNDING NEAR KBRO SHOWING THE INFILTRATION OF THE DRIER AIR IN
THE UPPER AND MID LEVEL OF THE ATMOSPHERE AND A DROP IN THE PWAT
VALUES TO 1.34 INCHES AND INTO 1.10 INCHES TOWARDS THE WEST. THE
DRIER AIR MASS FROM THE RIDGE BUILDING ACROSS THE WESTERN PLAINS
WILL SET UP THAT DRIER AND WARM PATTERN FOR MOST OF THE LONG TERM
FORECAST. HIGH TEMPERATURES THURSDAY THROUGH SUNDAY WILL BE WARM AND
HUMID REACHING THE MID TO UPPER 90S THROUGH THE WEEK. ANOTHER TROUGH
DIGS SOUTHWARD ALONG BAJA CALIFORNIA AND SWING NORTHEASTWARD INTO
THE CENTRAL PLAINS SATURDAY AND SUNDAY. THE MAIN IMPACT WITH THIS
SYSTEM FOR SOUTH TEXAS WILL BE THE SE WINDS AND THE ABUNDANT WARM
TEMPERATURES ACROSS THE CWA WITH NO CONVECTION AS THE SYSTEM REMAINS
NORTH OF THE CWA. EXPECT SURFACE GRADIENT TO INCREASE WITH BREEZE TO
CONDITIONS THIS WEEKEND.
NEXT WEEK...THE TROUGH WILL CONTINUE TO MOVE NORTHEAST AND STRENGTHEN
ITS SURFACE TROUGH OVER NORTH CENTRAL PLAINS. THIS WILL CONTINUE TO
KEEP THE AREA UNDER SOUTHEAST WINDS ACROSS THE CWA. BY TUESDAY...THE
HIGH PRESSURE ALOFT BUILDS FROM THE SOUTH AND A VERY WEAK GRADIENT
AT THE SURFACE RETURNS. LOW TEMPERATURES FOR MUCH OF THE LONG TERM
FORECAST REMAIN IN THE MID 70S ACROSS THE AREA.
&&
.MARINE...TONIGHT THROUGH WEDNESDAY NIGHT...SEAS WERE NEAR 4 FEET WITH
SOUTHEAST WINDS NEAR 10 KNOTS AT BUOY020 EARLY THIS AFTERNOON. WINDS
WILL INCREASE ACROSS THE COASTAL WATERS TONIGHT AS THE PRESSURE
GRADIENT INCREASES ACROSS THE WESTERN GULF OF MEXICO. MODERATE TO
STRONG SOUTHEAST WINDS WILL PREVAIL TONIGHT WITH SCEC CONDITIONS
LIKELY OFFSHORE. THE SCEC CONDITIONS WILL PERSIST WEDNESDAY INTO WED
NIGHT...ESPECIALLY OFFSHORE...AS THE PRESSURE GRADIENT REMAINS
STRONG ACROSS THE LOWER TEXAS COAST.
THURSDAY THROUGH TUESDAY...
THE UPPER LEVEL SYSTEM OVER THE BAJA CA WILL FINALLY BEGIN TO MOVE
NORTHEAST WEDNESDAY INTO THURSDAY LIMITING THE AREA OF ANY
CONVECTION. THE SURFACE HIGH PRESSURE OVER THE SOUTHEAST PLAINS WILL
BEGIN TO SHIFT SOUTH OVER THE GULF WATERS SHIFTING WINDS ACROSS THE
GULF TOWARDS THE SE. WINDS WILL INCREASE THURSDAY AFTERNOON WITH
POSSIBLE SCA FOR MUCH OF THE DAY AND EARLY EVENING AS WINDS INCREASE.
THIS SE FLOW WILL PREVAIL FOR MUCH OF THE LONG TERM FORECAST BUT WILL
WEAKEN BY NEXT WEEK. SEAS WILL BE BETWEEN 4 TO 5 FEET OVER THE GULF
WATERS AS THERE WILL BE A LONG DURATION FETCH OVER THE GULF. THE UPPER
AND LOWER FLOW WILL WEAKEN AND KEEP THE WAVE HEIGHT 5 FEET OR LESS.
&&
.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL 75 83 74 86 / 40 40 20 10
BROWNSVILLE 72 84 72 89 / 40 40 20 10
HARLINGEN 72 87 73 92 / 40 40 20 10
MCALLEN 74 90 74 95 / 50 40 20 0
RIO GRANDE CITY 73 92 73 98 / 50 30 10 0
SOUTH PADRE ISLAND 75 80 75 81 / 40 40 20 10
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
61/67
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT
ISSUED AT 327 PM CDT TUE MAY 14 2013
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A REMNANT
NOCTURNAL MCS DIMINISHING ACROSS NORTHERN AND CENTRAL WISCONSIN
EARLY THIS AFTERNOON AFTER IT PRODUCED LIGHT SHOWERS OVER PARTS OF
THE AREA. AT THE SURFACE...A WARM FRONT EXTENDS FROM AN AREA OF LOW
PRESSURE OVER SOUTH-CENTRAL MINNESOTA TO NORTHEAST ILLINOIS. AND A
COLD FRONT ALSO EXTENDS FROM THAT SURFACE LOW SOUTHWEST TO THE
PANHANDLE OF NEBRASKA. TEMPERATURES TO THE SOUTHWEST OF THE WARM
FRONT ARE IN THE UPPER 80S TO 100 DEGREES...BUT STILL PLENTY OF 70S
TO THE NORTH OF THE BOUNDARY. CONVECTION ALONG EITHER BOUNDARY HAS
FAILED TO DEVELOP SO FAR. THE LATEST MESOANALYSIS SUGGESTS SB CIN
HAS BEEN ERODING OVER NE IOWA WHICH APPEARS TO BE THE MOSTLY LIKELY
LOCATION OF THUNDERSTORM DEVELOPMENT LATER THIS AFTERNOON. WITH
TEMPS EXPECTED TO TOP OUT ONLY IN THE 70S TO LOWER 80S ACROSS OUR
REGION THIS AFTERNOON...HAVING A HARD TIME SEEING ANY THUNDERSTORM
DEVELOPMENT IN OUR AREA...ESPECIALLY SINCE THERE IS NO SURFACE BASED
NOR MOST UNSTABLE CAPE AS OF YET...AND DEWPOINTS ARE IN THE LOWER
40S. WILL CONSEQUENTLY REMOVE ANY THUNDERSTORM CHANCES FOR THE REST
OF THE AFTERNOON. AS THE LOW MOVES ACROSS THE REGION
TONIGHT...SMALL PRECIP CHANCES ARE THE MAIN FORECAST CONCERN.
TONIGHT...WEAK LOW PRESSURE WILL MOVE FROM FAR NW WISCONSIN ACROSS
THE UPPER PENINSULA THIS EVENING. AS THIS OCCURS...AN 850MB WARM
FRONT WILL LIFT ACROSS NE WISCONSIN EARLY IN THE EVENING WHILE THE
COLD FRONT WILL SWEEP FROM NW TO SE ACROSS THE STATE MID TO LATE
EVENING. DESPITE THE WARM SECTOR REACHING INTO CENTRAL AND
EAST-CENTRAL WISCONSIN THIS EVENING...12Z SOUNDINGS FROM MPX AND DVN
AND PROGGED SOUNDINGS ALL INDICATE AMPLE DRY AIR BELOW 600 AND
700MB. ONLY SB CAPES EXISTING ACROSS THE REGION CURRENTLY ARE OVER
SW MN AND IOWA WHERE TEMPS RANGE FROM THE UPPER 80S TO THE UPPER
90S. NOT GOING TO COME CLOSE TO REACHING THOSE READINGS THIS
EVENING...SO THE POSSIBILITY OF STORMS DEVELOPING WITHIN THE WARM
SECTOR SEEMS TOO LOW TO MENTION IN THE FORECAST. IF STORMS WERE TO
DEVELOP...THE BEST CHANCES APPEAR TO BE OVER FAR N-C TO FAR NE
WISCONSIN EARLY TO MID EVENING DUE TO SOME INDICATIONS FROM THE RUC
OF THE NOSE OF THE LLJ POINTED IN THAT DIRECTION. IN ADDITION...THERE
IS SOME ELEVATED CAPE IN THE 850-800MB LAYER AROUND 850 J/KG AND
THAT REGION WOULD BE CLOSER TO THE EDGE OF THE MID-LEVEL CAP.
CAPPING WILL REMAIN TOUGH TO OVERCOME...SINCE BUFKIT SOUNDINGS
INDICATE ELEVATED CIN UPWARDS OF 150 J/KG. WILL LEAVE AN ISOLATED
STORM IN THE FORECAST FOR THIS REGION TONIGHT...BUT
ADMITTEDLY...CHANCES ARE QUITE SMALL. IF STORMS DO FIRE...STRONG
SHEAR WOULD SUPPORT ORGANIZATION THAT COULD LEAD TO HAIL AND STRONG
GUSTY WINDS. THE THREAT OF ISOLATED STORMS WILL DEPART LATE THIS
EVENING AND SKIES WILL BECOME CLEAR OVERNIGHT. WARM EVENING TEMPS
WILL FALL INTO THE 50S FOR LOWS TONIGHT.
.LONG TERM...WEDNESDAY THROUGH TUESDAY
ISSUED AT 327 PM CDT TUE MAY 14 2013
MAIN FCST CONCERNS INCLUDE FIRE WEATHER POTENTIAL ON WEDS/THURS...THEN
PCPN TRENDS FOR THE END OF THIS WEEK AND EARLY NEXT WEEK.
A VERY DRY AIR MASS WILL RESIDE OVER THE REGION FROM WEDNESDAY INTO
THURSDAY...WITH DEEP MIXING ALLOWING TEMPERATURES TO WARM NICELY...
AND ALSO CAUSING DEW POINTS TO PLUMMET DURING THE AFTERNOONS. HIGH
TEMPERATURES WILL BE WELL INTO THE 70S BOTH DAYS.
MODELS AGREE ON A GRADUAL RETURN OF PCPN CHANCES FROM THE WEST LATE
THURSDAY NIGHT AND INTO THE WEEKEND. THE LATEST TRENDS DON`T SUPPORT
AS MUCH OF A WASHOUT FOR THE WEEKEND AS WAS PREVIOUSLY SUSPECTED...
SO POPS HAVE BEEN LOWERED A BIT AND TEMPERATURES ARE EXPECTED TO BE
A LITTLE WARMER. RIGHT NOW...THE GREATEST THREAT OF SIGNIFICANT PCPN
APPEARS TO BE DURING THE SUNDAY NIGHT THROUGH MONDAY NIGHT TIME FRAME...
AS A LOW PRESSURE SYSTEM AND ASSOCIATED FRONTAL SYSTEM MOVES THROUGH.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1230 PM CDT TUE MAY 14 2013
WEAKENING MID-LEVEL DISTURBANCE WILL GENERATE SCT VERY
LIGHT SHOWERS OVER NORTH-CENTRAL AND CENTRAL WISCONSIN THROUGH
MID-AFTERNOON...BUT CONDITIONS TO REMAIN VFR. THEN LOW PRESSURE
WILL MOVE ACROSS CENTRAL MINNESOTA AND THE UPPER PENINSULA TONIGHT.
ISOLATED STORMS ARE POSSIBLE AHEAD OF THIS LOW...MAINLY ACROSS THE
UPPER PENINSULA...BUT THINK THE AIRMASS WILL BE TOO DRY FOR
THUNDERSTORM DEVELOPMENT OVER CENTRAL AND NORTHERN WISCONSIN. LLWS
TO DEVELOPMENT THIS EVENING AHEAD OF THE LOW...AND THEN BEHIND THE
LOW AS WELL. VFR CONDITIONS EXPECTED TOMORROW WITH GUSTY NORTHWEST
WINDS.
&&
.FIRE WEATHER...
ISSUED AT 327 PM CDT TUE MAY 14 2013
TEMPERATURES IN THE 70S AND MINIMUM RELATIVE HUMIDITIES OF 20 TO 25
PERCENT IN THE SANDY SOIL AREAS CAN BE EXPECTED ON WEDS AND THURS.
NORTHWEST WINDS WILL GUST TO AROUND 30 MPH IN FAR NE WI ON WEDNESDAY
AFTERNOON...SETTING THE STAGE FOR A CRITICAL FIRE WEATHER DAY. A
FIRE WEATHER WATCH WILL BE ISSUED FOR FAR NE WI FROM NOON THROUGH
7 PM ON WEDNESDAY. WINDS WILL NOT BE AS STRONG ON THURSDAY...SO
HEADLINES SHOULD NOT BE NEEDED THEN.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY
EVENING FOR WIZ012-013-073.
&&
$$
SHORT TERM.....MPC
LONG TERM......KIECKBUSCH
AVIATION.......MPC
FIRE WEATHER...KIECKBUSCH
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1230 PM CDT TUE MAY 14 2013
UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND WEDNESDAY
ISSUED AT 436 AM CDT TUE MAY 14 2013
FORECAST CONCERNS ON TEMPERATURES TODAY AND CHANCE FOR
THUNDERSTORMS LATER THIS AFTERNOON AND THIS EVENING. HAVE TRENDED
TOWARDS GEM/NAM FOR GUIDANCE ON THIS PACKAGE. ECMWF NOW TRENDING
TOWARDS NAM WITH BETTER CHANCE FOR PCPN A BIT FURTHER SOUTH INTO
CENTRAL WI CLOSER TO WARM FRONT POSITION.
LAST EVENING SOUNDINGS SHOWS WHAT THE ISSUE WITH THIS
FORECAST...THAT BEING TOO DRY. AREA OF HIGH BASED SHOWERS WENT
THROUGH LAST NIGHT AROUND MIDNIGHT ASSOCIATED WITH STRONG WAA/850
WARM FRONT. NOTHING MORE THAN SPRINKLES SEEN. MID CLOUDINESS NOW
EXITING EASTERN WI.
FOCUS ON FAST MOVING SHORT WAVE ALONG CANADIAN BORDER AND FRONTAL
SYSTEM NOW MOVING THROUGH NORTHERN PLAINS. BY MID AFTERNOON...WARM FRONT
TO LIFT NORTH INTO SOUTHWEST WI. RATHER WARM AIR MASS TO PUSH INTO
STATE TODAY WITH 850 TEMPS INTO THE 20S OVER CENTRAL WI. WITH STEEP
MID-LEVEL LAPSE RATES BETWEEN 8 AND 9 C/KM....AND WARM
FRONT...WILL CONTINUE TO CARRY SMALL/ISOLD CHANCE FOR
THUNDERSTORMS. MODEL SOUNDINGS SUGGEST STRONG CIN THROUGH THE DAY
GIVEN DRY AIRMASS BELOW 600MB. SOUNDINGS ALSO SHOW CAPE HIGH
BASED...MAINLY ABOVE 600MB. THIS TO LEAD TO HIGH BASED
THUNDERSTORM THREAT...WHICH IF STORMS DO DEVELOP WOULD LIKELY LEAD TO
GUSTY WINDS...POSSIBLY HAIL. COLD FRONT TO PUSH THROUGH STATE BY
MIDNIGHT LEADING TO DRY FORECAST FOR REST OF NIGHT AND WEDNESDAY.
ON WEDNESDAY...GUSTY NORTHWEST WINDS BEHIND FRONT AND LOW
HUMIDITIES WITH MIXING TO 5K FEET OR HIGHER MAY LEAD TO INCREASED
FIRE DANGER.
TEMPERATURES TO BE WELL ABOVE NORM TODAY...DROPPING CLOSER TO
NORMS ON WEDNESDAY. FEW MODELS...INCLUDING HRRR SUGGEST 90 INTO
SOUTHWEST WI. HAVE BUMPED TEMPS UP SLIGHTLY THROUGHOUT CWA.
.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY
ISSUED AT 436 AM CDT TUE MAY 14 2013
SURFACE HIGH PRESSURE MOVING ACROSS THE REGION AHEAD OF AN UPPER
LEVEL RIDGE SHOULD KEEP THE EARLY PART OF THE LONG TERM FORECAST
DRY. THE 00Z NAM AND 00Z GFS GENERATED SOME QPF DURING THE DAY ON
THURSDAY...BUT SINCE THE 00Z ECMWF...PREVIOUS FORECAST AND
SURROUNDING GRIDS WERE DRY...A DRY FORECAST APPEARED TO BE THE WAY
TO GO.
A SHORT WAVE AND WARM ADVECTION AHEAD OF A SURFACE TROUGH
APPROACHING FROM THE PLAINS WILL BRING A CHANCE OF SHOWERS AND
THUNDERSTORMS TO THE AREA STARTING ON FRIDAY. VARIOUS SHORT WAVES
AHEAD OF THE MAIN UPPER TROUGH AND A SURFACE FRONTAL
BOUNDARY...COMBINED WITH A FEED OF GULF MOISTURE AHEAD OF A
DEVELOPING SURFACE LOW WILL KEEP AT LEAST A CHANCE OF SHOWERS AND
THUNDERSTORMS THROUGH THE END OF THE FORECAST PERIOD.
CLOUDS AND PRECIPITATION WILL KEEP TEMPERATURES FROM WARMING TOO
MUCH ABOVE NORMAL DURING THE DAYTIME...BUT THE SAME FACTORS SHOULD
KEEP TEMPERATURES WELL ABOVE NORMAL AT NIGHT.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1230 PM CDT TUE MAY 14 2013
WEAKENING MID-LEVEL DISTURBANCE WILL GENERATE SCT VERY
LIGHT SHOWERS OVER NORTH-CENTRAL AND CENTRAL WISCONSIN THROUGH
MID-AFTERNOON...BUT CONDITIONS TO REMAIN VFR. THEN LOW PRESSURE
WILL MOVE ACROSS CENTRAL MINNESOTA AND THE UPPER PENINSULA TONIGHT.
ISOLATED STORMS ARE POSSIBLE AHEAD OF THIS LOW...MAINLY ACROSS THE
UPPER PENINSULA...BUT THINK THE AIRMASS WILL BE TOO DRY FOR
THUNDERSTORM DEVELOPMENT OVER CENTRAL AND NORTHERN WISCONSIN. LLWS
TO DEVELOPMENT THIS EVENING AHEAD OF THE LOW...AND THEN BEHIND THE
LOW AS WELL. VFR CONDITIONS EXPECTED TOMORROW WITH GUSTY NORTHWEST
WINDS.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....TE
LONG TERM......MG
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
627 AM CDT TUE MAY 14 2013
UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND WEDNESDAY
ISSUED AT 436 AM CDT TUE MAY 14 2013
FORECAST CONCERNS ON TEMPERATURES TODAY AND CHANCE FOR
THUNDERSTORMS LATER THIS AFTERNOON AND THIS EVENING. HAVE TRENDED
TOWARDS GEM/NAM FOR GUIDANCE ON THIS PACKAGE. ECMWF NOW TRENDING
TOWARDS NAM WITH BETTER CHANCE FOR PCPN A BIT FURTHER SOUTH INTO
CENTRAL WI CLOSER TO WARM FRONT POSITION.
LAST EVENING SOUNDINGS SHOWS WHAT THE ISSUE WITH THIS
FORECAST...THAT BEING TOO DRY. AREA OF HIGH BASED SHOWERS WENT
THROUGH LAST NIGHT AROUND MIDNIGHT ASSOCIATED WITH STRONG WAA/850
WARM FRONT. NOTHING MORE THAN SPRINKLES SEEN. MID CLOUDINESS NOW
EXITING EASTERN WI.
FOCUS ON FAST MOVING SHORT WAVE ALONG CANADIAN BORDER AND FRONTAL
SYSTEM NOW MOVING THROUGH NORTHERN PLAINS. BY MID AFTERNOON...WARM FRONT
TO LIFT NORTH INTO SOUTHWEST WI. RATHER WARM AIR MASS TO PUSH INTO
STATE TODAY WITH 850 TEMPS INTO THE 20S OVER CENTRAL WI. WITH STEEP
MID-LEVEL LAPSE RATES BETWEEN 8 AND 9 C/KM....AND WARM
FRONT...WILL CONTINUE TO CARRY SMALL/ISOLD CHANCE FOR
THUNDERSTORMS. MODEL SOUNDINGS SUGGEST STRONG CIN THROUGH THE DAY
GIVEN DRY AIRMASS BELOW 600MB. SOUNDINGS ALSO SHOW CAPE HIGH
BASED...MAINLY ABOVE 600MB. THIS TO LEAD TO HIGH BASED
THUNDERSTORM THREAT...WHICH IF STORMS DO DEVELOP WOULD LIKELY LEAD TO
GUSTY WINDS...POSSIBLY HAIL. COLD FRONT TO PUSH THROUGH STATE BY
MIDNIGHT LEADING TO DRY FORECAST FOR REST OF NIGHT AND WEDNESDAY.
ON WEDNESDAY...GUSTY NORTHWEST WINDS BEHIND FRONT AND LOW
HUMIDITIES WITH MIXING TO 5K FEET OR HIGHER MAY LEAD TO INCREASED
FIRE DANGER.
TEMPERATURES TO BE WELL ABOVE NORM TODAY...DROPPING CLOSER TO
NORMS ON WEDNESDAY. FEW MODELS...INCLUDING HRRR SUGGEST 90 INTO
SOUTHWEST WI. HAVE BUMPED TEMPS UP SLIGHTLY THROUGHOUT CWA.
.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY
ISSUED AT 436 AM CDT TUE MAY 14 2013
SURFACE HIGH PRESSURE MOVING ACROSS THE REGION AHEAD OF AN UPPER
LEVEL RIDGE SHOULD KEEP THE EARLY PART OF THE LONG TERM FORECAST
DRY. THE 00Z NAM AND 00Z GFS GENERATED SOME QPF DURING THE DAY ON
THURSDAY...BUT SINCE THE 00Z ECMWF...PREVIOUS FORECAST AND
SURROUNDING GRIDS WERE DRY...A DRY FORECAST APPEARED TO BE THE WAY
TO GO.
A SHORT WAVE AND WARM ADVECTION AHEAD OF A SURFACE TROUGH
APPROACHING FROM THE PLAINS WILL BRING A CHANCE OF SHOWERS AND
THUNDERSTORMS TO THE AREA STARTING ON FRIDAY. VARIOUS SHORT WAVES
AHEAD OF THE MAIN UPPER TROUGH AND A SURFACE FRONTAL
BOUNDARY...COMBINED WITH A FEED OF GULF MOISTURE AHEAD OF A
DEVELOPING SURFACE LOW WILL KEEP AT LEAST A CHANCE OF SHOWERS AND
THUNDERSTORMS THROUGH THE END OF THE FORECAST PERIOD.
CLOUDS AND PRECIPITATION WILL KEEP TEMPERATURES FROM WARMING TOO
MUCH ABOVE NORMAL DURING THE DAYTIME...BUT THE SAME FACTORS SHOULD
KEEP TEMPERATURES WELL ABOVE NORMAL AT NIGHT.
&&
.AVIATION...FOR 12Z TAF ISSUANCE
ISSUED AT 612 AM CDT TUE MAY 14 2013
LLWS CONDITIONS TO PERSIST THROUGH 15Z IN THE EAST...OTHERWISE VFR
CONDITIONS WILL CONTINUE THROUGH THE PERIOD. ISOLD TO SCT
THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON INTO TONIGHT AS A
WARM/COLD FRONT MOVE THROUGH THE STATE. THUNDERSTORMS EXPECTED TO
BE HIGH BASED WITH STRONG...GUSTY WINDS POSSIBLE WITH ANY THUNDERSTORM
THAT DEVELOPS.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....TE
LONG TERM......MG
AVIATION.......TE
FORECAST DISCUSSION FOR ROUTINE MORNING FORECAST ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND WEDNESDAY
ISSUED AT 436 AM CDT TUE MAY 14 2013
FORECAST CONCERNS ON TEMPERATURES TODAY AND CHANCE FOR
THUNDERSTORMS LATER THIS AFTERNOON AND THIS EVENING. HAVE TRENDED
TOWARDS GEM/NAM FOR GUIDANCE ON THIS PACKAGE. ECMWF NOW TRENDING
TOWARDS NAM WITH BETTER CHANCE FOR PCPN A BIT FURTHER SOUTH INTO
CENTRAL WI CLOSER TO WARM FRONT POSITION.
LAST EVENING SOUNDINGS SHOWS WHAT THE ISSUE WITH THIS
FORECAST...THAT BEING TOO DRY. AREA OF HIGH BASED SHOWERS WENT
THROUGH LAST NIGHT AROUND MIDNIGHT ASSOCIATED WITH STRONG WAA/850
WARM FRONT. NOTHING MORE THAN SPRINKLES SEEN. MID CLOUDINESS NOW
EXITING EASTERN WI.
FOCUS ON FAST MOVING SHORT WAVE ALONG CANADIAN BORDER AND FRONTAL
SYSTEM NOW MOVING THROUGH NORTHERN PLAINS. BY MID AFTERNOON...WARM FRONT
TO LIFT NORTH INTO SOUTHWEST WI. RATHER WARM AIR MASS TO PUSH INTO
STATE TODAY WITH 850 TEMPS INTO THE 20S OVER CENTRAL WI. WITH STEEP
MID-LEVEL LAPSE RATES BETWEEN 8 AND 9 C/KM....AND WARM
FRONT...WILL CONTINUE TO CARRY SMALL/ISOLD CHANCE FOR
THUNDERSTORMS. MODEL SOUNDINGS SUGGEST STRONG CIN THROUGH THE DAY
GIVEN DRY AIRMASS BELOW 600MB. SOUNDINGS ALSO SHOW CAPE HIGH
BASED...MAINLY ABOVE 600MB. THIS TO LEAD TO HIGH BASED
THUNDERSTORM THREAT...WHICH IF STORMS DO DEVELOP WOULD LIKELY LEAD TO
GUSTY WINDS...POSSIBLY HAIL. COLD FRONT TO PUSH THROUGH STATE BY
MIDNIGHT LEADING TO DRY FORECAST FOR REST OF NIGHT AND WEDNESDAY.
ON WEDNESDAY...GUSTY NORTHWEST WINDS BEHIND FRONT AND LOW
HUMIDITIES WITH MIXING TO 5K FEET OR HIGHER MAY LEAD TO INCREASED
FIRE DANGER.
TEMPERATURES TO BE WELL ABOVE NORM TODAY...DROPPING CLOSER TO
NORMS ON WEDNESDAY. FEW MODELS...INCLUDING HRRR SUGGEST 90 INTO
SOUTHWEST WI. HAVE BUMPED TEMPS UP SLIGHTLY THROUGHOUT CWA.
.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY
ISSUED AT 436 AM CDT TUE MAY 14 2013
SURFACE HIGH PRESSURE MOVING ACROSS THE REGION AHEAD OF AN UPPER
LEVEL RIDGE SHOULD KEEP THE EARLY PART OF THE LONG TERM FORECAST
DRY. THE 00Z NAM AND 00Z GFS GENERATED SOME QPF DURING THE DAY ON
THURSDAY...BUT SINCE THE 00Z ECMWF...PREVIOUS FORECAST AND
SURROUNDING GRIDS WERE DRY...A DRY FORECAST APPEARED TO BE THE WAY
TO GO.
A SHORT WAVE AND WARM ADVECTION AHEAD OF A SURFACE TROUGH
APPROACHING FROM THE PLAINS WILL BRING A CHANCE OF SHOWERS AND
THUNDERSTORMS TO THE AREA STARTING ON FRIDAY. VARIOUS SHORT WAVES
AHEAD OF THE MAIN UPPER TROUGH AND A SURFACE FRONTAL
BOUNDARY...COMBINED WITH A FEED OF GULF MOISTURE AHEAD OF A
DEVELOPING SURFACE LOW WILL KEEP AT LEAST A CHANCE OF SHOWERS AND
THUNDERSTORMS THROUGH THE END OF THE FORECAST PERIOD.
CLOUDS AND PRECIPITATION WILL KEEP TEMPERATURES FROM WARMING TOO
MUCH ABOVE NORMAL DURING THE DAYTIME...BUT THE SAME FACTORS SHOULD
KEEP TEMPERATURES WELL ABOVE NORMAL AT NIGHT.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1034 PM CDT MON MAY 13 2013
MID LEVEL CLOUDS WITH ISOLATED SHOWERS WILL LINGER
EASTERN WISCONSIN OVERNIGHT. LLWS CONDITIONS TO PERSIST THROUGH
15Z TUESDAY. VFR CONDITIONS WILL CONTINUE TUESDAY...WITH PERHAPS A
CHANCE OF A MVFR CIGS WITH SHOWERS OR A THUNDERSTORM TUESDAY NIGHT
WITH THE PASSAGE OF A COLD FRONT.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....TE
LONG TERM......MG
AVIATION.......TDH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
407 PM MDT TUE MAY 14 2013
.SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT)
ISSUED AT 234 PM MDT TUE MAY 14 2013
WIDESPREAD CUMULUS HAVE DEVELOPED ALONG THE SOUTHERN ZONES THIS
AFTERNOON IN A VERY DEEP BOUNDARY LAYER. RADAR IS SHOWING SOME
WEAK SHOWERS OUT THERE...HOWEVER ITS PROBABLY MOSTLY VIRGA WITH
GUSTY WINDS. THIS ISOLATED SHOWER ACTIVITY WILL LIKELY CONTINUE
INTO THE EVENING AS THE RUC SHOWS AROUND 100-200 J/KG OF CAPE
THROUGH AROUND 03Z. LAPS ANALYSIS SHOWS A WEAK FRONT LOCATED FROM
DOUGLAS TO SIDNEY WITH HIGHER LLVL MOISTURE (DEWPOINTS IN THE 40S)
BEHIND IT AND THE MUCH DRIER AIR TO THE SOUTH OF IT. THE MODELS
HAVE THIS BOUNDARY PUSHING TO THE SOUTHWEST OVERNIGHT AND STALLING
ALONG THE LARAMIE RANGE IN THE MORNING. BOTH THE GFS AND NAM SHOW
SOME IMPRESSIVE LLVL MOISTURE BEING ADVECTED IN ON EAST-TO-
SOUTHEAST WINDS BY THE MORNING. INCREASED DEWPOINTS INTO THE LOW-
TO-MID 40S OVER THE PLAINS OF SOUTHEAST WY FROM WEDNESDAY MORNING
THROUGH THE AFTERNOON.
THE COMBINATION OF HIGHER LLVL MOISTURE AND SLIGHTLY COOLER
MIDLEVEL TEMPS ON WEDNESDAY AFTERNOON WILL RESULT IN GOOD SFC
INSTABILITY ALONG AND EAST OF THE LARAMIE RANGE. THE GFS AND NAM
BOTH SHOW LIFTED INDICES OF -3C TO -5C WHICH TRANSLATES INTO
1000-1250 J/KG OF CAPE. THE TREND OF THE MODELS HAS BEEN TO
INCREASE CONVECTIVE POTENTIAL AND QPF FOR WEDNESDAY AFTERNOON AND
EVENING. FOR THIS REASON...UP POPS INTO THE CHANCE CATEGORY OVER
THE MTNS AND PLAINS. THE DEEP LAYER SHEAR DOES NOT LOOK IMPRESSIVE
OVER THE SOUTHERN ZONES (AROUND 20 KTS)...HOWEVER FURTHER TO THE
NORTH ACROSS CONVERSE/NIOBRARA COUNTIES THE MIDLEVEL WINDS ARE
STRONGER AND 0-6KM SHEAR APPROACHES 40 KTS. SO IT LOOKS LIKE THAT
WILL BE THE REGION TO MONITOR FOR STRONGER STORMS WITH SOME SMALL
HAIL POTENTIAL. THE STORMS THAT DEVELOP OVER THE LARAMIE RANGE IN
THE EARLY AFTERNOON WILL PROGRESS EASTWARD INTO PORTIONS OF THE
WESTERN NEBRASKA PANHANDLE BY THE EARLY EVENING. TEMPS WILL BE
AROUND 10 DEGREES COOLER ON WEDNESDAY WITH THE MOIST SE SFC WINDS
AND GREATER CLOUD COVER.
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 234 PM MDT TUE MAY 14 2013
THURSDAY...WEAK SHORTWAVE RIDGING ALOFT. WILL SEE ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS...PRIMARILY ORIENTED ALONG THE SURFACE
TROUGH AXIS FROM EASTERN WYOMING SOUTHWARD THROUGH EASTERN COLORADO.
FRIDAY...FLOW ALOFT BACKS TO SOUTHWEST IN ADVANCE OF NEXT SHORTWAVE
TROUGH ALOFT. QUITE WARM WITH A DECENT LOW LEVEL THERMAL RIDGE
ORIENTED NORTH TO SOUTH ALONG A DECENT SURFACE TROUGH OVER OUR
COUNTIES. ISOLATED AFTERNOON AND EVENING THUNDERSTORMS ALONG A LOW
LEVEL CONVERGENCE AXIS FROM CASPER TO CHADRON TO SIDNEY...WITH AREAL
COVERAGE OF THUNDERSTORMS MINIMIZED BY WARM TEMPERATURES ALOFT
PROVIDING SIGNIFICANT CONVECTIVE INHIBITION...CIN.
SATURDAY...DECENT NEGATIVELY TILTED SHORTWAVE TROUGH ALOFT ROTATES
EASTWARD ACROSS OUR COUNTIES AND ALONG WITH ITS ASSOCIATED PACIFIC
ORIGIN COLD FRONT...EXPECT ISOLATED TO SCATTERED AFTERNOON AND
EVENING THUNDERSTORMS...MOST NUMEROUS NEAR THE MOUNTAINS DUE TO
DIFFERENTIAL HEATING AND OROGRAPHIC EFFECTS.
SUNDAY...A DEFINITE BRITISH ISLES COASTAL FEEL TYPE DAY. BRISK
WINDS...COOLER TEMPERATURES AND ISOLATED TO SCATTERED AFTERNOON AND
EVENING SHOWERS AND THUNDERSTORMS ON TAP WITH NORTHWEST FLOW ALOFT
AND ENOUGH LOW AND MID LEVEL MOISTURE TO BE LIFTED BY DAYTIME
HEATING EFFECTS AND CYCLONIC FLOW ALOFT. LOW LEVEL DOWNSLOPE WINDS
WILL PRODUCE A RAIN SHADOW EFFECT FROM WHEATLAND TO CHEYENNE AND
MINIMIZE PRECIPITATION COVERAGE.
MONDAY...REFRESHINGLY COOL START TO THE TRADITIONAL WORKWEEK IN THE
WAKE OF THE RELATIVELY STRONG SHORTWAVE TROUGH PASSAGE AND WITH COOL
NORTH WINDS IN USHERING IN RELATIVELY COOL CANADIAN AIR. ISOLATED
AFTERNOON SHOWERS AND THUNDERSTORMS. TEMPERATURES WILL STILL BE NEAR
NORMAL THOUGH.
TUESDAY...TRANSITORY SHORTWAVE RIDGE ALOFT MOVES ACROSS OUR COUNTIES
AND ALONG WITH MUCH LESS LOW AND MID LEVEL MOISTURE...ONLY ISOLATED
AFTERNOON AND EVENING THUNDERSTORMS EXPECTED.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY AFTERNOON)
ISSUED AT 402 PM MDT TUE MAY 14 2013
VFR PREVAILS.
THROUGH 02Z TONIGHT...ISOLATED HIGH BASED SHOWERS AND THUNDERSTORMS
WILL AFFECT THE LARAMIE AND CHEYENNE TAFS WITH GUSTY AND ERRATIC
WINDS AS ISOLATED SHOWERS AND THUNDERSTORMS DEVELOP OVER AND NEAR
THE SNOWY...SIERRA MADRE AND SOUTHERN LARAMIE RANGES. SHOWERS AND
THUNDERSTORMS WILL PRODUCE LOCALIZED TURBULENCE.
PERIODS OF SCATTERED TO BROKEN LOW AND MIDDLE CLOUDS AT OR ABOVE
6000 FEET AGL.
A WEAK COLD FRONT WILL MOVE SOUTHWESTWARD TO THE LEE OF THE LARAMIE
RANGE THIS EVENING. SURFACE HIGH PRESSURE WILL MOVE INTO SOUTH
DAKOTA TONIGHT PRODUCING WEAK LOW LEVEL UPSLOPE SOUTH AND
SOUTHEAST WINDS ACROSS TAF SITES. LOW LEVEL SOUTH AND SOUTHEAST
WINDS WILL STRENGTHEN WEDNESDAY MORNING...WITH SCATTERED CUMULUS
AND TOWERING CUMULUS DEVELOPMENT ALONG AND WEST OF INTERSTATE 25
BY LATE MORNING...ALONG WITH ISOLATED THUNDERSTORMS IN THIS AREA
TOWARDS NOON. SCATTERED SHOWERS AND THUNDERSTORMS WILL DEVELOP
OVER SOUTHEAST WYOMING AFTER NOON WEDNESDAY PRODUCING LOCALIZED
MVFR AND ERRATIC AND GUSTY WINDS TO 50 MPH.
&&
.FIRE WEATHER...
ISSUED AT 234 PM MDT TUE MAY 14 2013
RELATIVE HUMIDITY VALUES HAVE DROPPED BELOW 15 PERCENT THIS
AFTERNOON ACROSS MUCH OF THE LOWER ELEVATIONS IN A VERY WARM
AIRMASS. WINDS HAVE BECOME WEAK NORTHERLY OVER THE PANHANDLE
BEHIND A WEAK FRONT...WITH GUSTS GENERALLY BELOW 20 MPH.
TEMPERATURES ON WEDNESDAY ARE EXPECTED TO BE AROUND 10 DEGREES
COOLER WITH SOUTHEAST WINDS ALONG AND EAST OF THE LARAMIE RANGE.
THE INCREASING LOW LEVEL MOISTURE WILL PROMOTE SCATTERED SHOWERS
AND THUNDERSTORMS ON WEDNESDAY AFTERNOON AND EVENING.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...FINCH
LONG TERM...RUBIN
AVIATION...RUBIN
FIRE WEATHER...FINCH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
303 PM MDT TUE MAY 14 2013
.SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT)
ISSUED AT 234 PM MDT TUE MAY 14 2013
WIDESPREAD CUMULUS HAVE DEVELOPED ALONG THE SOUTHERN ZONES THIS
AFTERNOON IN A VERY DEEP BOUNDARY LAYER. RADAR IS SHOWING SOME
WEAK SHOWERS OUT THERE...HOWEVER ITS PROBABLY MOSTLY VIRGA WITH
GUSTY WINDS. THIS ISOLATED SHOWER ACTIVITY WILL LIKELY CONTINUE
INTO THE EVENING AS THE RUC SHOWS AROUND 100-200 J/KG OF CAPE
THROUGH AROUND 03Z. LAPS ANALYSIS SHOWS A WEAK FRONT LOCATED FROM
DOUGLAS TO SIDNEY WITH HIGHER LLVL MOISTURE (DEWPOINTS IN THE 40S)
BEHIND IT AND THE MUCH DRIER AIR TO THE SOUTH OF IT. THE MODELS
HAVE THIS BOUNDARY PUSHING TO THE SOUTHWEST OVERNIGHT AND STALLING
ALONG THE LARAMIE RANGE IN THE MORNING. BOTH THE GFS AND NAM SHOW
SOME IMPRESSIVE LLVL MOISTURE BEING ADVECTED IN ON EAST-TO-
SOUTHEAST WINDS BY THE MORNING. INCREASED DEWPOINTS INTO THE LOW-
TO-MID 40S OVER THE PLAINS OF SOUTHEAST WY FROM WEDNESDAY MORNING
THROUGH THE AFTERNOON.
THE COMBINATION OF HIGHER LLVL MOISTURE AND SLIGHTLY COOLER
MIDLEVEL TEMPS ON WEDNESDAY AFTERNOON WILL RESULT IN GOOD SFC
INSTABILITY ALONG AND EAST OF THE LARAMIE RANGE. THE GFS AND NAM
BOTH SHOW LIFTED INDICES OF -3C TO -5C WHICH TRANSLATES INTO
1000-1250 J/KG OF CAPE. THE TREND OF THE MODELS HAS BEEN TO
INCREASE CONVECTIVE POTENTIAL AND QPF FOR WEDNESDAY AFTERNOON AND
EVENING. FOR THIS REASON...UP POPS INTO THE CHANCE CATEGORY OVER
THE MTNS AND PLAINS. THE DEEP LAYER SHEAR DOES NOT LOOK IMPRESSIVE
OVER THE SOUTHERN ZONES (AROUND 20 KTS)...HOWEVER FURTHER TO THE
NORTH ACROSS CONVERSE/NIOBRARA COUNTIES THE MIDLEVEL WINDS ARE
STRONGER AND 0-6KM SHEAR APPROACHES 40 KTS. SO IT LOOKS LIKE THAT
WILL BE THE REGION TO MONITOR FOR STRONGER STORMS WITH SOME SMALL
HAIL POTENTIAL. THE STORMS THAT DEVELOP OVER THE LARAMIE RANGE IN
THE EARLY AFTERNOON WILL PROGRESS EASTWARD INTO PORTIONS OF THE
WESTERN NEBRASKA PANHANDLE BY THE EARLY EVENING. TEMPS WILL BE
AROUND 10 DEGREES COOLER ON WEDNESDAY WITH THE MOIST SE SFC WINDS
AND GREATER CLOUD COVER.
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 234 PM MDT TUE MAY 14 2013
THURSDAY...WEAK SHORTWAVE RIDGING ALOFT. WILL SEE ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS...PRIMARILY ORIENTED ALONG THE SURFACE
TROUGH AXIS FROM EASTERN WYOMING SOUTHWARD THROUGH EASTERN COLORADO.
FRIDAY...FLOW ALOFT BACKS TO SOUTHWEST IN ADVANCE OF NEXT SHORTWAVE
TROUGH ALOFT. QUITE WARM WITH A DECENT LOW LEVEL THERMAL RIDGE
ORIENTED NORTH TO SOUTH ALONG A DECENT SURFACE TROUGH OVER OUR
COUNTIES. ISOLATED AFTERNOON AND EVENING THUNDERSTORMS ALONG A LOW
LEVEL CONVERGENCE AXIS FROM CASPER TO CHADRON TO SIDNEY...WITH AREAL
COVERAGE OF THUNDERSTORMS MINIMIZED BY WARM TEMPERATURES ALOFT
PROVIDING SIGNIFICANT CONVECTIVE INHIBITION...CIN.
SATURDAY...DECENT NEGATIVELY TILTED SHORTWAVE TROUGH ALOFT ROTATES
EASTWARD ACROSS OUR COUNTIES AND ALONG WITH ITS ASSOCIATED PACIFIC
ORIGIN COLD FRONT...EXPECT ISOLATED TO SCATTERED AFTERNOON AND
EVENING THUNDERSTORMS...MOST NUMEROUS NEAR THE MOUNTAINS DUE TO
DIFFERENTIAL HEATING AND OROGRAPHIC EFFECTS.
SUNDAY...A DEFINITE BRITISH ISLES COASTAL FEEL TYPE DAY. BRISK
WINDS...COOLER TEMPERATURES AND ISOLATED TO SCATTERED AFTERNOON AND
EVENING SHOWERS AND THUNDERSTORMS ON TAP WITH NORTHWEST FLOW ALOFT
AND ENOUGH LOW AND MID LEVEL MOISTURE TO BE LIFTED BY DAYTIME
HEATING EFFECTS AND CYCLONIC FLOW ALOFT. LOW LEVEL DOWNSLOPE WINDS
WILL PRODUCE A RAIN SHADOW EFFECT FROM WHEATLAND TO CHEYENNE AND
MINIMIZE PRECIPITATION COVERAGE.
MONDAY...REFRESHINGLY COOL START TO THE TRADITIONAL WORKWEEK IN THE
WAKE OF THE RELATIVELY STRONG SHORTWAVE TROUGH PASSAGE AND WITH COOL
NORTH WINDS IN USHERING IN RELATIVELY COOL CANADIAN AIR. ISOLATED
AFTERNOON SHOWERS AND THUNDERSTORMS. TEMPERATURES WILL STILL BE NEAR
NORMAL THOUGH.
TUESDAY...TRANSITORY SHORTWAVE RIDGE ALOFT MOVES ACROSS OUR COUNTIES
AND ALONG WITH MUCH LESS LOW AND MID LEVEL MOISTURE...ONLY ISOLATED
AFTERNOON AND EVENING THUNDERSTORMS EXPECTED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY MORNING)
ISSUED AT 1106 AM MDT TUE MAY 14 2013
VFR PREVAILS.
THROUGH 02Z TONIGHT...ISOLATED HIGH BASED SHOWERS AND THUNDERSTORMS
MAY AFFECT THE LARAMIE AND CHEYENNE TAFS WITH GUSTY AND ERRATIC
WINDS AS ISOLATED SHOWERS AND THUNDERSTORMS DEVELOP OVER AND NEAR
THE SNOWY...SIERRA MADRE AND SOUTHERN LARAMIE RANGES. SHOWERS
AND THUNDERSTORMS WILL PRODUCE LOCALIZED TURBULENCE.
PERIODS OF SCATTERED TO BROKEN LOW AND MIDDLE CLOUDS AT OR ABOVE
6000 FEET AGL.
A WEAK COLD FRONT WILL MOVE SOUTHWESTWARD TO THE LEE OF THE LARAMIE
RANGE THIS AFTERNOON AND THIS EVENING. SURFACE HIGH PRESSURE WILL
MOVE INTO SOUTH DAKOTA TONIGHT PRODUCING WEAK LOW LEVEL UPSLOPE
SOUTH AND SOUTHEAST WINDS ACROSS TAF SITES. LOW LEVEL SOUTH AND
SOUTHEAST WINDS WILL STRENGTHEN WEDNESDAY MORNING...WITH
SCATTERED CUMULUS AND TOWERING CUMULUS DEVELOPMENT ALONG AND
WEST OF INTERSTATE 25 BY LATE MORNING...ALONG WITH ISOLATED
THUNDERSTORMS IN THIS AREA TOWARDS NOON.
&&
.FIRE WEATHER...
ISSUED AT 234 PM MDT TUE MAY 14 2013
RELATIVE HUMIDITY VALUES HAVE DROPPED BELOW 15 PERCENT THIS
AFTERNOON ACROSS MUCH OF THE LOWER ELEVATIONS IN A VERY WARM
AIRMASS. WINDS HAVE BECOME WEAK NORTHERLY OVER THE PANHANDLE
BEHIND A WEAK FRONT...WITH GUSTS GENERALLY BELOW 20 MPH.
TEMPERATURES ON WEDNESDAY ARE EXPECTED TO BE AROUND 10 DEGREES
COOLER WITH SOUTHEAST WINDS ALONG AND EAST OF THE LARAMIE RANGE.
THE INCREASING LOW LEVEL MOISTURE WILL PROMOTE SCATTERED SHOWERS
AND THUNDERSTORMS ON WEDNESDAY AFTERNOON AND EVENING.
&&
.HYDROLOGY...
ISSUED AT 234 PM MDT TUE MAY 14 2013
TEMPERATURES THIS AFTERNOON HAVE CLIMBED INTO THE 60S ACROSS THE
SNOWY AND SIERRA MADRE RANGES. LATEST RIVER GAGES ON THE
RIVERS IN CARBON AND ALBANY COUNTY ARE SHOWING A STEADY INCREASE
IN RIVER LEVELS...PEAKING OUT DURING THE LATE EVENING. THOUGH
RIVERS ARE EXPECTED TO STAY WITHIN THEIR BANKS...OUTDOOR
ENTHUSIASTS OR PERSONS LIVING NEAR THESE RIVERS IN SOUTHEAST
WYOMING NEED TO MONITOR RIVERS AND STREAMS NEAR THEIR CAMPSITES OR
HOMES IN CASE RAPID RISES DO OCCUR. THERE IS STILL PLENTY OF SNOW
PACK THAT WILL MELT OVER THE NEXT FEW DAYS AS TEMPERATURES WILL
REMAIN ABOVE NORMAL THROUGH FRIDAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...FINCH
LONG TERM...RUBIN
AVIATION...RUBIN
FIRE WEATHER...FINCH
HYDROLOGY...FINCH
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
335 AM EDT THU MAY 16 2013
.SYNOPSIS...
07Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS BROAD MID/UPPER LEVEL
RIDGING OVER THE SE CONUS AND FL PENINSULA EARLY THIS MORNING WHICH
WILL BE QUICKLY DE-AMPLIFYING THROUGH THE DAY/EVENING IN RESPONSE TO
THE APPROACH OF SHORTWAVE ENERGY EJECTING EASTWARD FROM THE SOUTHERN
PLAINS. THIS SHORTWAVE ENERGY WAS RESPONSIBLE FOR A SEVERE
WEATHER/TORNADO OUTBREAK ACROSS TEXAS THIS PAST EVENING...HOWEVER IT
WILL ENCOUNTER VERY DIFFERENT CONDITIONS AS IT PASSES BY OUR
REGION...AND IS LIKELY TO EXIT THE FORECAST AREA WITHOUT FANFARE.
16/00Z KTBW SOUNDING PROFILE SHOWED THE INFLUENCE OF THE UPPER RIDGE
WITH A WEAK SUBSIDENCE INVERSION AT THE TOP OF THE MIXING LAYER
AROUND 800MB. 800MB IS AROUND 7000KFT...SO VERY IMPRESSIVE MIXING ON
WEDNESDAY...ALTHOUGH NOT UNUSUAL FOR MAY. SKIES REMAIN MOSTLY CLEAR
ACROSS THE REGION OTHER THAN SOME PASSING THIN HIGH LEVEL CIRRUS
FROM TIME TO TIME. MORE IN THE WAY OF CLOUDS CAN BE SEEN TO OUR WEST
ACROSS THE CENTRAL GULF OF MEXICO WITHIN THE SYNOPTIC FORCING AHEAD
OF THE APPROACHING SHORTWAVE. SOME OF THIS MID/HIGH LEVEL CLOUDINESS
WILL BE CROSSING THE REGION LATER TODAY INTO THURSDAY...MAINLY OVER
CENTRAL/NORTHERN ZONES.
AT THE SURFACE...SUBTROPICAL RIDGE AXIS REMAINS STUCK IN PLACE FROM
OFF THE NE FLORIDA COAST BACK WESTWARD THROUGH THE NATURE COAST AND
INTO THE NE GULF OR MEXICO. THIS POSITION WILL REMAIN GENERALLY
UNCHANGED FOR THE NEXT SEVERAL DAYS...WITH PERHAPS A SLIGHT
NORTHWARD ADVANCEMENT OVER THE WEEKEND.
&&
.SHORT TERM (TODAY THROUGH SATURDAY)...
TODAY/TONIGHT...
LITTLE CHANGE IN FORECAST PHILOSOPHY OVER THE PAST 24 HOURS WITH
RESPECT TO THE FORECAST FOR THE FINAL TWO DAYS OF THE WORK WEEK.
MID/UPPER LEVEL RIDGE QUICKLY BREAKS DOWN TODAY AND IS SUPPRESSED
SOUTHWARD IN RESPONSE TO THE APPROACH AND ARRIVAL OF SHORTWAVE
ENERGY MOVING EASTWARD ALONG THE NORTHERN GULF COAST. OVERALL THIS
ENERGY WILL BEGIN TO SHEAR OUT AND BECOME MORE BROAD IN NATURE AS IT
NEARS THE NORTHERN PART OF FLORIDA. HOWEVER...THE OVERALL SYNOPTIC
FORCING OVERSPREADING THE REGION IS NOT ALL THAT WEAK...AND NORMALLY
WOULD BE EXPECTING ASSOCIATED SHOWER CHANCES. HOWEVER...THIS TIME
AROUND...COLUMN MOISTURE BELOW 500MB WILL SIMPLY BE LACKING...AND
THE ENVIRONMENT IS QUITE HOSTILE FOR CONVECTION TO BECOME ESTABLISH
WITH A DEEP LAYER (850-600MB) OF THETA-E VALUES BELOW 320K. WILL
CONTINUE TO LEAVE MENTION OF ANY SHOWERS OUT OF THE FORECAST. THE
ONLY REAL "IMPACT" WE SHOULD SEE FROM THIS PASSING ENERGY WILL BE A
BAND OF MID/HIGH LEVEL CLOUDS...AGAIN MAINLY OVER THE NORTHERN
ZONES. A FAVORABLE ENVIRONMENT SHOULD AGAIN ALLOW THE BOUNDARY LAYER
TO MIX UP TO AT LEAST 6KFT BY LATE AFTERNOON. 850-800MB TEMPS AROUND
14-15C WILL MIX DOWN EASILY INTO THE MIDDLE 80 INLAND WITH WARMER
SPOTS INTO THE UPPER 80S. SLIGHTLY COOLER AT THE BEACHES AS FLOW
TURNS ONSHORE FOR THE AFTERNOON. LOW TEMPERATURES TONIGHT ONLY DROP
TO THE LOWER 60S FOR THE COOLEST SPOTS.
FRIDAY/FRIDAY NIGHT...
SHORTWAVE AXIS WILL CROSS THE AREA DURING THE DAY AND EXIT TO OUR
EAST FRIDAY NIGHT. ENSEMBLE MODEL GUIDANCE STILL AGREES IN A SMALL
INCREASE IN OVERALL COLUMN MOISTURE FOR MOST SPOTS (OR AT LEAST A
THINNER LAYER OF SUPER DRY AIR) AND WILL KEEP A SLIGHT CHANCE 20%
POP IN THE GRIDS FOR AN AFTERNOON/EVENING SHOWER. THESE ISOLATED
SHOWERS WILL GENERALLY BE AWAY FROM THE BEACHES AS THE SEA-BREEZE
MAKES AT LEAST SOME INLAND PROGRESS. ANY CONVECTIVE CELLS WILL
HOWEVER STILL HAVE TO OVERCOME A GENERALLY HOSTILE THETA-E
ENVIRONMENT BETWEEN 5-15KFT. THIS HOSTILE ENVIRONMENT SHOULD KEEP
COVERAGE OF AFTERNOON CONVECTION LOW. TEMPERATURES WILL BE
SEASONABLE...WITH WARMER INLAND LOCATIONS REACHING THE LOWER 90 BY
MID/LATE AFTERNOON. OVERNIGHT LOWS FRIDAY NIGHT IN THE 60S INLAND
AND ALONG THE NATURE COAST AND AROUND 70 FOR TAMPA BAY SOUTHWARD
ALONG THE IMMEDIATE SUNCOAST.
SATURDAY...
A SUMMER-LIKE DAY APPEARS IN STORE FOR THE FIRST HALF OF THE
UPCOMING WEEKEND. MAIN SHORTWAVE WILL BE GONE TO OUR WEST...HOWEVER
THE MID/UPPER LEVEL PATTERN LEFT BEHIND IN ITS WAKE WILL REMAIN WEAK
OR "BAGGY" IN NATURE. THIS LACK OF SYNOPTIC SUPPRESSION ALONG WITH
AN INCREASINGLY FAVORABLE MOISTURE PROFILE SHOULD RETURN OUR
FORECAST TO CHANCE POPS (30-40%) DURING THE AFTERNOON/EARLY EVENING
HOURS. NOT LOOKING FOR A WET DAY BY ANY MEANS...BUT RATHER JUST A
MORE TYPICAL DISTRIBUTION OF BRIEF SEA-BREEZE CONVECTION. GOOD
MIXING AND 850MB BETWEEN 15-16C WILL HELP PUSH MANY SPOTS AWAY FROM
THE BEACHES INTO THE LOWER 90S. ENJOY!
&&
.LONG TERM (SUNDAY THROUGH NEXT WEDNESDAY)...
THE PERIOD BEGINS WITH AN UPPER LEVEL TROUGH FROM THE CANADIAN
ROCKIES TO THE FOUR CORNERS REGION...A RIDGE OVER THE WESTERN GULF
THAT REACHES NORTH TO THE UPPER MIDWEST...AND WEAK TROUGHING DOWN
THE EASTERN SEABOARD. THROUGH MID-WEEK THE WESTERN TROUGH DEEPENS
INTO A CLOSED LOW AS IT TRACKS EAST...TO THE MID WEST OR UPPER GREAT
LAKES...AND FLATTENS THE GULF RIDGE. MEANWHILE THE WEAK TROUGHING
CONTINUES ALONG OR JUST OFF THE EAST COAST AS IT SETTLES SOUTHWARD.
AT THE SURFACE...HIGH PRESSURE OVER THE ATLANTIC ALONG LATITUDE 30
NORTH...REINFORCED BY HIGH PRESSURE MOVING SOUTH FROM NEW ENGLAND
EARLY IN THE WEEK...RIDGES WEST ACROSS THE SE U.S. AND FL TO THE
CENTRAL GULF COAST DURING THE PERIOD.
THERE ARE SOME DIFFERENCES IN THE MODEL SOLUTIONS BUT THESE ARE
EXPECTED TO HAVE LIMITED IMPACT TO THE AREA...SO THE FORECAST
PHILOSOPHY CONTINUES WITH LITTLE CHANGE. A PREVAILING EAST AND SE
LOW LEVEL FLOW...BUT SLACK ENOUGH FOR AFTERNOON SEA BREEZES...
PROVIDES AMPLE MOISTURE WHICH ALONG WITH SEA BREEZE BOUNDARIES
AND A WEAK PATTERN ALOFT RESULTS IN SLIGHT CHANCE TO CHANCE
THUNDERSTORMS. THE TIMING WILL FAVOR MAINLY AFTERNOON AND EVENING.
TEMPERATURES WILL RUN NEAR NORMAL FOR THE LOWS WHILE
HIGHS WILL BE NEAR TO A DEGREE OR TWO ABOVE.
&&
.AVIATION...
VFR CONDITIONS THROUGH THE NEXT 24 HOURS WITH FEW TO SCT CLOUDS.
LIGHT EAST WINDS BECOME SE AFTER SUNRISE THEN TAKE ON A BAY/SEA
BREEZE COMPONENT DURING THE AFTERNOON.
&&
.MARINE...
THE SUBTROPICAL RIDGE AXIS WILL REMAIN IN PLACE ACROSS THE NORTHEAST
GULF OF MEXICO INTO THE UPCOMING WEEKEND. PATTERN THROUGH SATURDAY
WILL RESULT IN GENERALLY EAST TO WEST FLOW DURING THE OVERNIGHT AND
MORNING HOURS WITH THE FLOW THEN WEAKENING AND BECOMING VARIABLE FOR
THE AFTERNOON AND EVENING...WHILE ONSHORE SEA BREEZES DEVELOP NEAR
THE COAST. CHANCES FOR AN AFTERNOON OR EVENING THUNDERSTORM WILL
INCREASE DURING THE UPCOMING WEEKEND NEAR THE COAST...HOWEVER IT
CURRENTLY APPEARS THAT MOST OF THE STORMS SHOULD REMAIN A BIT
INLAND.
&&
.FIRE WEATHER...
SURFACE HIGH PRESSURE REMAINS IN CONTROL OF THE REGION THROUGH THE
UPCOMING WEEKEND. RELATIVE HUMIDITY WILL BRIEFLY APPROACH CRITICAL
LEVELS THIS AFTERNOON AND AGAIN ON FRIDAY AFTERNOON AWAY FROM THE
COAST...BUT EXTENDED DURATIONS OF THESE LOW RELATIVE HUMIDITY VALUES
ARE NOT EXPECTED...AND NO RED FLAG WARNINGS ARE REQUIRED. THE SLOW
INCREASE IN LOW LEVEL MOISTURE WILL CONTINUE INTO THE UPCOMING
WEEKEND AND SHOULD PREVENT ANY CRITICAL LEVELS OF RELATIVE HUMIDITY
FOR SATURDAY AND SUNDAY. THE FORECAST WILL ALSO SEE INCREASING
CHANCES FOR WIDELY SCATTERED AFTERNOON AND EVENING STORMS INTO THE
UPCOMING WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 87 69 88 72 / 0 0 10 10
FMY 89 67 90 71 / 10 10 20 20
GIF 88 66 91 67 / 0 0 20 10
SRQ 86 67 85 70 / 0 10 10 10
BKV 88 60 89 64 / 0 10 10 10
SPG 86 73 87 74 / 0 0 10 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/MARINE/FIRE WEATHER...MROCZKA
LONG TERM/AVIATION/DECISION SUPPORT...RUDE
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1143 PM CDT WED MAY 15 2013
.DISCUSSION...
ISSUED 837 PM CDT WED MAY 15 2013
STATIONARY FRONTAL BOUNDARY BISECTS CENTRAL ILLINOIS THIS
EVENING...WITH COOLER/SLIGHTLY DRIER AIR FILTERING INTO THE FAR
NORTHERN KILX CWA WHERE DEWPOINTS HAVE DROPPED INTO THE UPPER 40S
AND LOWER 50S. FURTHER SOUTH...MOISTURE POOLING ALONG THE BOUNDARY
HAS RESULTED IN DEWPOINTS IN THE LOWER 60S ALONG THE I-72
CORRIDOR. 01Z/8PM IR SATELLITE IMAGERY IS BEGINNING TO SHOW AC
DEVELOPING ALONG THE FRONT...WITH REGIONAL RADAR SHOWING SCATTERED
THUNDERSTORMS DEVELOPING FURTHER WEST ACROSS NORTHERN MISSOURI.
23Z HRRR SUGGESTS CONVECTION WILL DEVELOP EASTWARD ALONG THE
FRONT INTO WEST-CENTRAL ILLINOIS AFTER 03Z/10PM. BASED ON POSITION
OF FRONT AND LATEST HIGH-RES MODEL DATA...HAVE LOWERED POPS TO
JUST SLIGHT CHANCE ACROSS THE SE CWA ALONG/SOUTH OF I-70. FURTHER
NORTH...WENT WITH SCATTERED WORDING ACROSS THE CENTRAL AND
NORTHERN ZONES IN CLOSER PROXIMITY TO THE BOUNDARY. ALSO ADJUSTED
OVERNIGHT LOWS UP A FEW DEGREES...WITH LOWER TO MIDDLE 60S IN MOST
LOCATIONS...EXCEPT COOLER UPPER 50S FAR NORTH. ZONE UPDATE HAS
ALREADY BEEN ISSUED.
&&
.AVIATION...
ISSUED 1142 PM CDT WED MAY 15 2013
STATIONARY FRONTAL BOUNDARY CURRENTLY DRAPED ACROSS THE AREA WILL
BE THE MAIN FOCUSING MECHANISM FOR WIDELY SCATTERED SHOWERS/THUNDER
THROUGH THE ENTIRE 06Z TAF PERIOD. LATEST RADAR IMAGERY SHOWS
SCATTERED CONVECTION IMMEDIATELY AHEAD OF THE FRONT SOUTH OF THE
I-72 CORRIDOR...WITH ANOTHER BROKEN LINE OF SHOWERS/STORMS
DEVELOPING FURTHER NORTH ALONG THE UPPER-LEVEL FRONT FROM THE
PEORIA AREA WESTWARD. SINCE NO TERMINAL IS IMMEDIATELY THREATENED
BY CONVECTION AT THIS TIME...WILL JUST CARRY VCTS ACROSS THE
BOARD. MODEL SOLUTIONS VARY OVERNIGHT...HOWEVER BOTH THE NAM AND
HRRR STILL SUGGEST A DIMINISHING TREND...WHICH WILL BE FOLLOWED
FOR THIS FORECAST ISSUANCE. WILL THEREFORE END THUNDER MENTION
AFTER 09Z. SCATTERED SHOWERS/THUNDER WILL RE-DEVELOP ON THURSDAY
AS THE FRONT BEGINS TO SLOWLY LIFT BACK NORTHWARD. WILL BRING VCTS
BACK INTO THE FORECAST AT KSPI AND KDEC AFTER 14Z...SPREADING
NORTH TO KPIA BY 20Z. WINDS WILL INITIALLY BE LIGHT/VARIABLE
TONIGHT INTO THURSDAY MORNING...THEN WILL BECOME SOUTHERLY BY
AFTERNOON AND EVENING AS THE FRONT SHIFTS NORTHWARD.
BARNES
&&
.PREV DISCUSSION...
ISSUED 259 PM CDT WED MAY 15 2013
FORECAST CONCERN TODAY IS THE POPS ASSOCIATED WITH THE STALLING
FRONT OVER THE REGION INTO THE WEEKEND...AND THEN THE APPROACH OF
THE MAIN UPPER WAVE AND FRONT THE FIRST PART OF NEXT WEEK.
.SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT.
MORNING UPPER AIR DATA AND SPC INSTABILITY ANALYSIS SHOWS THE
EAST-WEST FRONTAL ZONE HAD MADE INTO THE NORTH CENTRAL PART OF IL
TODAY...WITH ENOUGH CONVERGENCE ON THE BOUNDARY TO CONTINUE THE
TREND THAT BEGAN OVERNIGHT...OF ELEVATED CONVECTION FORMING AND
MOVING EAST ALONG THE FRONTAL ZONE. THIS TREND HAS BEEN THE CASE
ALL DAY...AS THE UPPER AIR SHOWED A TONGUE OF LOW LEVEL MOISTURE
SURGING NORTH FROM TX OVER MO INTO THE BOUNDARY ZONE. SPC MESODATA
CONTINUED TO SHOW AIR SOUTH OF THE BOUNDARY CAPPED AND THE PCPN
REMAINING ELEVATED. EXPECT THIS TREND TO REMAIN OVERNIGHT...WITH
THE FRONT SAGGING A LITTLE SOUTH.
WITH THE FRONT PROGGED TO BE IN THE REGION BY ALL THE MODELS ON
THURSDAY...WILL KEEP POPS IN THE LIKELY CAT THROUGH CENTRAL REGION.
ADDITIONAL SUPPORT FOR DEVELOPMENT WITH UPPER LEVEL REMAINS OF THE
WEAKENING UPPER WAVE THAT IS OVER TX TODAY. THAT SYSTEM WILL BE
DRIFTING TO THE EAST NORTHEAST OVER OK TO AR. THIS SYSTEM IS
FORECAST TO WASH OUT THURSDAY NIGHT AND THEN THE UPPER RIDGE
BEGINS TO START TO BUILD OVER AREA. LOWERING POPS THEN FRIDAY AND
INTO FRIDAY NIGHT.
.LONG TERM...SATURDAY THROUGH WEDNESDAY.
THE APPROACH OF THE DEEPENING UPPER LOW/WAVE ON SUNDAY GRADUALLY
INCREASES POPS OVER WEST SUNDAY. GFS AND NEW EUR ARE DIFFERENT IN
THE DETAILS ON THE APPROACHING FRONT AND THE UPPER LOW/TROUGH
CONFIGURATION. TODAYS RUN DOES NOT DISPLAY A CLEAR SYSTEM MOVING
THROUGH...BUT A MORE GRADUAL MOVEMENT OF THE UPPER SYSTEM...WHICH
RESULTS IN A LONGER PERIOD OF POPS...FOR SUNDAY INTO THE DAY
WEDNESDAY. WILL STILL HAVE TO WATCH MONDAY FOR SIGNIFICANT
CONVECTION...AS SOUNDING AND HODOGRAPH ON THAT DAY STILL SHOW
POTENTIAL FOR STRONG STORMS.
GOETSCH
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
131 AM EDT THU MAY 16 2013
.SYNOPSIS...
HIGH PRESSURE REMAINS CENTERED OFF THE MID ATLANTIC COAST THROUGH
FRIDAY. A WEAK FRONT APPROACHES THE AREA FROM THE NORTH THURSDAY
AFTERNOON THEN SETTLES OVER THE AREA FRIDAY INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
THE LATEST SURFACE ANALYSIS INDICATES A ~1022MB SURFACE HIGH
CENTERED OVER THE EAST-CENTRAL GULF COAST, WITH A SURFACE RIDGE
AXIS EXTENDING NE JUST OFF THE SOUTHEAST COAST. ALOFT, A RATHER
PROGRESSIVE NORTHERN STREAM FLOW EXISTS, WITH QUASI-ZONAL FLOW
ACROSS THE NORTHERN TIER OF STATES. MEANWHILE, WEAK SHORTWAVE
RIDGING HAS DEVELOPED ACROSS THE SOUTHEAST AHEAD OF CLOSED UPPER
LOW WHICH CONTINUES TO SLOWLY MEANDER ACROSS THE SOUTHERN PLAINS.
A WEAK DISTURBANCE DROPPING SE OF THE LOWER GRT LAKES HAVE
TRIGGERED A FEW ISOLATED SHRAS THIS EVENING, MAINLY ALONG AND
JUST SOUTH OF THE MASON-DIXON LINE INVOF FNTL BNDRY DRAPED NW-SE
FM SOUTH CENTRAL PA TO OH VLY THIS EVE. HRRR CONTINUES TO WEAKEN
THIS ACTIVITY JUST TO OUR NORTH, THOUGH POTENTIAL DOES EXIST FOR
AN ISOLATED SHRA OR TWO OVER FAR NORTHERN PART OF DORCHESTER,
WICOMICO, AND WORCESTER COUNTIES (US-50 AND NORTH) THROUGH ABOUT
6Z/2A OR SO BEFORE IT AND THE ASSD WARM FRONT CLEAR THE NORTHERN
MID-ATLANTIC COAST LATE TONIGHT. OTHERWISE, LOOK FOR A MILD,
COMFORTABLE OVERNIGHT, UNDER A CLEAR TO PARTLY CLOUDY SKY. EARLY
MORNING LOW TEMPS MAINLY IN THE L/M60S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY/...
FNTL BNDRY FM THE N BEGINS TO PUSH SLOLY S THU...REACHING NRN
AREAS OF FA IN THE AFTN...THEN TO THE S THU NGT INTO FRI. NOT THE
BEST FORCING OR DYNAMICS FOR ORGANIZED CNVTN...THOUGH SOME POOLING
OF SFC-LO LVL DEWPTS COMBINED W/ HEATING PTNTLLY ENOUGH FOR
ISOLD/SCT CNVTN. WILL CARRY 20-40% POPS ACRS THE FA THU AFTN INTO
THU NGT. THE BNDRY SHIFTS S TO NR OR JUST S OF THE NC/VA BRDR ON
FRI...W/ PSBL FOCUS FOR ANY PCPN FM CNTRL/SRN VA INTO NE NC. WHILE
ENOUGH TIME FOR DECENT WRMG ON THU (BEFORE THE BNDRY REACHES THE
FA)...WILL BE ABLE TO HAVE TEMPS REACH THE 80S XCP RIGHT AT THE
CST (ON THE ERN SHR). PSNY THU...THEN VRB CLDS OR MCLDY THU NGT
INTO FRI.
THE BNDRY TO RMN NRLY STNRY INVOF NRN NC LT FRI THROUGH SAT. SFC
HI PRES PASSING BY N AND THROUGH NEW ENG WILL LEAD TO ONSHR
WINDS...CONTD VRB CLDS OR MCLDY CONDS AND LO PROB FOR PCPN. HI
TEMPS SAT FM ARND 70F AT THE CST...TO MNLY THE M/U70S INLAND.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
A WEAK FRONTAL BOUNDARY WILL LINGER ACROSS THE MID-ATLANTIC SUNDAY.
THIS IS IN ADDITION TO A WEAK UPPER DISTURBANCE PASSING OVERHEAD
WILL PRODUCE A CHANCE FOR SHOWERS AND THUNDERSTORMS. AN H5 RIDGE
AXIS BUILDS OVER THEN EASTERN U.S. MON-WED OF NEXT WEEK. MODELS SHOW
A LOT OF UNCERTAINTY AS TO JUST HOW MUCH SHOWER/TSTM ACTIVITY WILL
OCCUR EARLY NEXT WEEK. DUE TO A LACK OF A TRIGGER TO GET ORGANIZED
TSTMS GOING...WILL LIMIT PCPN CHANCES TO THE 20-30% RANGE REACH DAY.
TEMPS WILL REMAIN ON THE WARM/MILD SIDE THROUGH THE PERIOD WITH
HIGHS IN THEN 70S AND 80S AND LOWS IN THE 60S.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
LOW PRESSURE WILL TRACK THROUGH SE CANADA TODAY AS AN ATTENDANT
COLD FRONT SLOWLY SAGS SWD INTO THE MID ATLANTIC. HIGH PRESSURE WILL
REMAIN OFF THE SOUTHEAST COAST. GENERALLY CLEAR SKIES THIS
MORNING...EXCEPT MID/UPPER LEVEL CLOUDS ASSOCIATED WITH THE FRONT
MOVING ACROSS NRN VA AND THE MD ERN SHORE. SW WINDS GENERALLY AOB
10 KT THIS MORNING WITH A FEW GUSTS UP TO 25 KT ALONG THE
IMMEDIATE COAST. FOR TODAY...NOT AS BREEZY AS WEDS AFTERNOON WITH
W/SW WINDS GENERALLY AROUND 10 TO 15 KT WITH GUSTS UP TO 20 KT. AS
THE FRONT DROPS INTO NRN VA THIS AFTERNOON...ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON INTO
THIS EVENING ACROSS THE REGION...GENERALLY NORTH OF THE NC/VA
BORDER. MVFR/IFR VSBYS POSSIBLE IN THUNDERSTORMS WITH GUSTS UP TO
35 KT. HOWEVER...CONFIDENCE IS NOT HIGH ATTM DUE TO LACK OF
COVERAGE...SO WILL NOT INCLUDE IN TAFS.
THE COLD FRONT WILL CONTINUE TO SLOWLY PROGRESS SWD...CROSSING THE
REGION LATE TONIGHT THROUGH FRIDAY. WINDS WILL BACK FROM THE W/SW
TO THE NW BEHIND THE FRONT. SHOWERS AND THUNDERSTORMS WILL AGAIN
BE POSSIBLE FRI AFTERNOON/EVENING...MAINLY ACROSS SRN VA/NRN NC.
THE FRONT WILL STALL OVER THE CAROLINAS THIS WEEKEND...WITH
ADDITIONAL SHOWERS AND THUNDERSTORMS POSSIBLE.
&&
.MARINE...
S-SW FLOW CONTINUES ACROSS THE MARINE AREA THROUGH LATE THIS EVENING
WITH MARGINAL SMALL CRAFT CONDITIONS (SAVE THE SOUTHERN COASTAL
WATERS). WILL LEAVE CURRENT HEADLINES UNCHANGED. WINDS TURN SW TO W
LATE TONIGHT AND DECREASE IN ADVANCE OF A BACKDOOR COLD FRONT THAT
SLOWLY SAGS SOUTHWARD THURS...CROSSING THE WATERS THURS NIGHT INTO FRI
BEFORE STALLING OVER THE CAROLINAS. WINDS WILL SHIFT FROM THE SW TO
THE N/NE POST FRONTAL...BUT EXPECTED TO REMAIN BELOW SCA THRESHOLDS.
E-SE WINDS LESS THAN 15 KT ARE EXPECTED OVER THE WEEKEND.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EDT EARLY THIS MORNING FOR
ANZ630>632-634.
SMALL CRAFT ADVISORY UNTIL 7 AM EDT THIS MORNING FOR ANZ650-
652-654.
&&
$$
SYNOPSIS...ALB/MPR
NEAR TERM...ALB
SHORT TERM...MPR
LONG TERM...JDM
AVIATION...SAM
MARINE...JDM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
139 AM EDT THU MAY 16 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 409 PM EDT WED MAY 15 2013
WV IMAGERY AND RUC ANALYSIS INDICATED WNW MID/UPPER LEVEL FLOW
THROUGH THE NRN GREAT LAKES ON THE SRN FLANK OF A TROUGH OVER NRN
ONTARIO TO THE SRN END OF JAMES BAY. A WEAK SHORTWAVE TROUGH
OVER THE SE CORNER OF MANITOBA SUPPORTED AN AREA OF MID CLOUDS AND
SOME SCT/ISOLD -SHRA INTO NW MN. AT THE SFC...A TIGHT PRES GRADIENT
PERSISTED BTWN A 995 MB LOW BTWN JAMES BAY AND LAKE SUPERIOR AND A
RIDGE FROM THE NRN PLAINS INTO SRN MN. WNW WINDS HAVE GUSTED AT OR
ABOVE 30 MPH OVER MUCH OF UPPER MI AND TO NEAR 45 MPH WHERE TERRAIN
HAS BOOSTED THE WINDS AT CMX. SUNSHINE WITH TEMPS INTO THE LOWER TO
MID 70S AND DEEP MIXING TO AROUND 750 MB HAS LOWERED DEWPOINTS TO
AROUND 30F WITH RH VALUES TO AROUND 20 PCT. THE COMBINATION OF THE
DRY AIR WINDS HAS RESULTED IN CRITICAL FIRE WEATHER CONDITIONS.
TONIGHT...AS THE PRES GRADIENT WEAKENS AND DAYTIME HEATING
SUBSIDES...WINDS WILL DIMINISH QUICKLY THIS EVENING AND BECOME LIGHT
OVERNIGHT. HIGHER RES SHORT RANGE MODELS SUGGEST THAT THE BEST
CHANCES OF PCPN ASSOCIATED WITH THE MANITOBA SHORTWAVE OVER THE SW
HALF OF UPPER MI. EVEN THERE...WITH DRY LOW LEVELS AND WEAK FORCING
WITH THE SHRTWV MAINLY JUST SPRINKLES AT MOST WOULD BE EXPECTED.
SO...ONLY A SMALL AREA OF SLIGHT CHANCE POPS WERE INCLUDED.
THURSDAY...EXPECT COOLER CONDITIONS OVER THE NORTH HALF OF UPPER MI
WITH NRLY WINDS BEHIND A COLD FRONT MOVING THROUGH THE AREA LATE
TONIGHT. WITH 850 MB TEMPS RANGING FROM AROUND 4C NORTH TO TO 9C
SOUTH...TEMPS SHOULD RANGE FROM THE LOWER 50S NEAR LAKE SUPERIOR TO
THE LOWER 70S INLAND SOUTHWEST. SUNSHINE AND FAVORABLE MIXING WILL
AGAIN DROP DEWPOINTS INTO THE LOWER 30S WITH RH VALUES TO AROUND 25
PERCENT SOUTH. HOWEVER...WITH WINDS ONLY TO AROUND 10 MPH...THE
WILDFIRE RISK WILL BE LOWER THAN TODAY.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 440 PM EDT WED MAY 15 2013
TEMPS WILL HOLD STEADY IN THE 60S ON FRIDAY AND SATURDAY...WITH A
WARM UP FOR SUNDAY AS SSE WINDS INCREASE AHEAD OF LOW PRESSURE
NEARING FROM THE CENTRAL PLAINS. AT THIS POINT THE STRONGER WINDS
LOOK TO BE ASSOCIATED WITH INCREASED DEW POINTS...LIMITING
SIGNIFICANT FIRE CONCERNS.
THERE IS A LOT OF UNCERTAINTY WITH THE MID TO LONGER RANGE OF THIS
FORECAST...WITH THE TRACK AND TIMING OF THE SLOW MOVING LOW PRESSURE
SYSTEM. WITH THAT SAID...THERE IS A SLIGHT CHANCE OF SHOWERS AND
THUNDERSTORMS IN THE FORECAST FROM SATURDAY ON /MAINLY WEST/.
THUNDERSTORM CHANCES ARE NOT THAT IMPRESSIVE. IT LOOKS LIKE THE BEST
CHANCE FOR SHOWERS AND THUNDERSTORMS ACROSS THE ENTIRE CWA WILL HOLD
OFF UNTIL MONDAY...WITH THE SFC LOW IS SET UP OVER THE EASTERN
DAKOTAS AND WESTERN MN. THE SYSTEM CONTINUES TO SLOW DOWN...AS IT
WAS ORIGINALLY EXPECTED TO CROSS UPPER MI ON SUNDAY...AT LEAST OF A
COUPLE OF DAYS AGO. NOW IT LOOKS TO HOLD OFF UNTIL TUESDAY AT THE
EARLIEST /12Z ECMWF SOLUTION/. THE GFS IS EVEN SLOWER...AND HAS THE
500MB LOW OVER ND TUESDAY AFTERNOON RETROGRADING AND CONSOLIDATING
WITH THE DEEP LOW PUSHING INTO THE PACIFIC NORTHWEST. WILL OPT FOR
FOR A SOLUTION CLOSER TO THE ECMWF AT THIS POINT...WITH LOWER
CONFIDENCE IN THE FORECAST BEYOND SUNDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 137 AM EDT THU MAY 16 2013
EXPECT VFR CONDITIONS/LIGHT N-E WINDS THIS TAF PERIOD WITH DRY HI
PRES DOMINATING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 PM EDT WED MAY 15 2013
EXPECT WINDS WITH GUSTS 25 KNOTS TO DIMINISH TONIGHT AS HIGH PRES
BUILDS INTO THE REGION. HIGH PRESSURE WILL EXPAND ACROSS GREAT LAKES
INTO THE WEEKEND WITH EAST-SOUTHEAST WINDS AT OR BLO 25 KTS. WINDS
BECOME SOUTHERLY LATE THIS WEEKEND AHEAD OF LOW PRESSURE TROUGH
PUSHING IN FROM NORTHERN PLAINS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1230 AM CDT THU MAY 16 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 348 PM CDT WED MAY 15 2013
FORECAST COULD BE PRETTY COMPLICATED CONCERNING CHANCES OF
PRECIPITATION FOR THE SHORT TERM.
FOR STARTERS...A NEARLY STATIONARY BOUNDARY IN OUR FAR SOUTHERN CWA
COULD BE THE FOCUS OF SOME AFTERNOON AND EVENING THUNDERSTORM
ACTIVITY. SHEAR IS EXTREMELY WEAK AND INSTABILITY IS MARGINAL AT
BEST. WE STILL HAVE INVERTED V SOUNDINGS...BUT NOT MIXING NEARLY AS
HIGH AS YESTERDAY...AND AIR NOT NEARLY AS DRY. OUR MAIN CONCERN
WOULD BE TO GET AN ISOLATED STRONG TO SEVERE WIND GUST...BUT THIS
WOULD BE A LONGSHOT. WENT CLOSER WITH RAP FOR DEWPOINTS AND WIND
WITHIN THE FIRST 6 TO 12 HOURS AS THE SOLUTIONS OF THIS MODEL HAVE
BEEN SUPERIOR TO OTHERS. I HAD TO INCREASE THE TOP END OF WIND
SPEEDS A BIT AS WE ARE MIXING A BIT BETTER THAN WHAT IS
FORECAST...BUT AS THE FRONT EDGES NORTH...WIND SPEEDS SHOULD
DECREASE ACROSS MUCH OF THE CWA. WENT TOWARD CONSRAW FOR DEWPOINTS
AS WE GET CLOSER TO THE OVERNIGHT HOURS INTO THURSDAY. THERE IS A
BIT OF A SIGNAL FOR SOME FOG TONIGHT FROM THE SREF SO WILL
CONTINUE WITH MENTIONING OF PATCHY FOG...ESPECIALLY AS THE FRONT
MOVES NORTH.
THE FORECAST GETS A LITTLE MUDDLED TONIGHT FOR PRECIPITATION
CHANCES. MODELS ARE GENERALLY LIFTING THE BOUNDARY TO THE NORTH AS A
WARM FRONT. THERE WILL NOT BE MUCH OF A LOW-LEVEL JET TO SUSTAIN ANY
CONVECTION THAT MIGHT FIRE UP THIS AFTERNOON AND EVENING. WITH
DECREASING WITH SUNSET...MOST CONVECTION SHOULD DIE OUT.
OVERNIGHT...HOWEVER...SOME MODELS ARE INDICATING THE POSSIBILITY OF
MORE CONVECTION MAINLY IN THE NORTHERN CWA. THE NMM INDICATES A
POSSIBLE SMALL-SCALE MCS DEVELOP OVER THE CWA OF LBF AND FOLLOW THE
BOUNDARY TO THE EAST ACROSS THE NORTHERN CWA...WHICH MAY POSSIBLY
LAST INTO THE EARLY MORNING HOURS.
THEN ANOTHER LULL IS LIKELY BY LATE MORNING THURSDAY INTO EARLY
AFTERNOON AS THE BOUNDARY TO THE NORTH EITHER CONTINUES TO LIFT
NORTH OR WASHES OUT...DEPENDING ON WHICH SOLUTION IS REALIZED.
EITHER WAY...A LULL IS LIKELY. A MID-LEVEL PERTURBATION IS STILL
FORECAST TO MOVE EAST ACROSS THE AREA BY THURSDAY AFTERNOON...BUT
AMPLITUDE SHOULD REMAIN QUITE LOW. AS A THETA E RIDGE SHIFTS
EAST...ALONG WITH THE WEAK PERTURBATION...WE SHOULD HAVE A GOOD SHOT
OF SOME SHOWERS AND THUNDERSHOWERS...ESPECIALLY WEST/INTO CENTRAL
PARTS OF THE CWA. MUCAPES WILL BE HIGH ENOUGH TO SUSTAIN
THUNDERSTORMS...BUT SHEAR WILL BE WEAK ONCE AGAIN...SO SEVERE
WEATHER WOULD NOT BE OUT OF THE QUESTION...BUT CERTAINLY NO OUTBREAK
IS ANTICIPATED.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 348 PM CDT WED MAY 15 2013
FOCUS OF THE LONG TERM PERIOD WILL CENTER AROUND CHANCES FOR
THUNDERSTORMS...SOME OF WHICH MIGHT BE POSSIBLY SEVERE AT
TIMES...MAINLY SATURDAY AFTERNOON THROUGH SUNDAY EVENING.
THE CUTOFF LOW ACROSS THE DESERT SOUTHWEST WILL FINALLY BEGIN TO
INGEST BACK INTO THE MEAN FLOW THROUGHOUT THE SHORT TERM...FINALLY
SHIFTING OFF TO THE SOUTHEAST ACROSS MISSOURI AND ARKANSAS BY
THURSDAY NIGHT. THROUGH THE OVERNIGHT PERIODS...A WEAK UPPER LEVEL
DISTURBANCE WILL BEGIN TO SHIFT ACROSS THE PLAINS...ON THE BACKSIDE
OF THE UPPER LEVEL LOW. MODELS DISAGREE ON THE DEPTH OF THE
WAVE...WITH THE ECMWF...UKMET AND NAM SOLUTIONS A BIT MORE SHALLOW
THAN THE DEEPER PROGRESSIVE GFS. AT THE SURFACE...MODELS INDICATE A
A DEVELOPING TROUGH ALONG THE FRONT RANGE OF THE ROCKIES...WITH SOME
SORT OF FRONT...WASHED OUT BOUNDARY SHIFTING NORTH OF THE OUTLOOK
AREA. COMBINED WITH THE WAVE AND WARM AIR ADVECTION...MODELS
CONTINUE TO HINT AT AT LEAST A CHANCE FOR PRECIPITATION...WITH THE
GFS HEDGING FURTHER SOUTH INTO KANSAS. AT THIS POINT...REALLY NOT
BUYING INTO THE SOUTHERN SOLUTION AND TRENDING MORE TOWARDS A
NEBRASKA RAIN EVENT.
AFTER THE PASSAGE OF THE UPPER LEVEL WAVE...SUBSIDENCE TAKES
HOLD...AND CURRENT THINKING IS THAT MUCH OF FRIDAY DURING THE DAY
WILL BE DRY. HOWEVER...BY FRIDAY AFTERNOON AND EVENING...ANOTHER
UPPER LEVEL TROUGH WILL BEGIN TO SHIFT INTO THE AREA. WITH THE
EASTWARD PROGRESSION OF THE TROUGH...HEIGHT FALLS...AND A SURFACE
LEESIDE TROUGH...ITS POSSIBLE WESTERN PORTIONS OF NEBRASKA COULD SEE
SOME CONVECTION FRIDAY AFTERNOON. A FAIRLY DECENT LLJ IS EXPECTED TO
DEVELOP ACROSS WESTERN AREAS AND SHIFT EASTWARD OVERNIGHT. THIS
COMBINED WITH A DECENT THETA E RIDGE OVER THE OUTLOOK AREA...WENT
AHEAD AND CONTINUED AT LEAST SLIGHT POPS OVERNIGHT. SHOULD STORMS
DEVELOP...THERE IS PLENTY OF INSTABILITY TO WORK WITH...ABOUT
2000-3000 J/KG. HOWEVER...A STRONG CAP EXISTS WITH 700 MB
TEMPERATURES NEAR 10 TO 11 DEGREES...AND BULK SHEAR IS LIMITED
AROUND 20 TO 30 KTS.
SATURDAY LOOKS TO BE THE MAIN FOCUS OF THE MID TERM PERIOD...AS THE
UPPER LEVEL LOW SHIFTS EASTWARD. BY SATURDAY AFTERNOON...THE SURFACE
TROUGH BECOMES ELONGATED ALONG THE FRONT RANGE. BOTH THE GFS AND
ECMWF SOLUTIONS HAVE BEGUN TO TREND A BIT SLOWER IN PREVIOUS
RUNS...BRINGING IN CHANCES FOR PRECIPITATION ACROSS THE
WEST...MAINLY DURING LATE AFTERNOON AND EVENING. INSTABILITY IS
QUITE HIGH DURING THE SATURDAY AFTERNOON PERIOD THROUGH
OVERNIGHT...WITH 4000 TO 5000 J/KG POSSIBLE. AGAIN...AS HAS BEEN THE
CASE MOST OF THIS WEEK...700 MB TEMPERATURES ARE ON THE ORDER OF 10
TO 12 AND EVEN 13 DEGREES AT TIMES. 0 TO 6 KM BULK SHEAR IS ALSO AT
ITS HIGHEST SATURDAY EVENING...CLIMBING TO NEAR 30 TO 40 KTS...WITH
50 KTS EXPECTED FURTHER WEST.
BY SUNDAY AFTERNOON...THE SURFACE TROUGH AND FRONTAL BOUNDARY WILL
FINALLY MIGRATE EASTWARD ACROSS THE CWA. THIS WILL GIVE US YET
ANOTHER CHANCE FOR PRECIPITATION...POSSIBLY SEVERE AS THE CWA
REMAINS SITUATED JUST ON THE EASTERN FRINGE OF THE UPPER LEVEL
TROUGH. THE ECMWF SOLUTIONS TENDS TO BE A BIT MORE PROGRESSIVE THAN
THE GFS SOLUTION WITH A CLOSED LOW ACROSS NORTHERN NEBRASKA BY 0Z
MONDAY...WHILE THE GFS REMAINS CLOSED OVER THE PANHANDLE. SEVERE IS
BEGINNING TO LOOK POSSIBLE ALSO ON SUNDAY. INSTABILITY DOES NOT LOOK
QUITE AS STRONG AS SATURDAY BUT STILL IS NEAR 2000 J/KG OF MOST
UNSTABLE CAPE. HOWEVER...THE CAP IS ALSO NOT QUITE AS STRONG WITH
700 MB TEMPERATURES ON THE ORDER OF 6 TO 7 DEGREES CELSIUS.
THEREFORE...SEVERE STORMS DO NOT LOOK OUT OF THE QUESTION FOR SUNDAY
AFTERNOON.
THROUGH THE REST OF THE LONG TERM...THE UPPER LEVEL LOW SPINS ACROSS
THE PLAINS GENERATING CHANCES FOR PRECIPITATION THROUGH MONDAY.
HOWEVER...AN UPPER LEVEL RIDGE LOOKS TO SLOWLY BEGIN TO BUILD ACROSS
THE DESERT SOUTHWEST TOWARDS THE BEGINNING OF NEXT WEEK. AS
SUCH...THE UPPER LEVEL LOW EJECTS NORTHWARD...WITH PRECIPITATION
QUICKLY EXITING THE REGION. DECIDED TO PULL OUT ANY SLIGHT MENTION
OF PRECIPITATION ALONG THE FRINGES OF THE CWA AS THE CWA SEEMS TO
BECOME DRY SLOTTED BY MONDAY NIGHT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1230 AM CDT THU MAY 16 2013
VFR CONDITIONS ARE EXPECTED AT THE TERMINAL DURING THE VALID TAF
PERIOD. MAIN CONCERN DURING THIS TAF PERIOD IS THE CHANCE FOR
THUNDERSTORMS THURSDAY AFTERNOON. THESE STORMS SHOULD BE ISOLATED
IN NATURE AND NOT WIDESPREAD. CHANCES WILL DIMINISH AFTER
MIDNIGHT TOMORROW. THERE COULD BE SOME PATCHY FOG IN THE MORNING
AROUND THE TERMINAL...HOWEVER...CONFIDENCE IS NOT HIGH AT THE
MOMENT AND WILL NOT MENTION THIS IN THE TAF FOR NOW. CONDITIONS
WILL BE MONITORED CLOSELY AND AN AMENDMENT MAY BE ISSUED LATER
THIS EVENING...IF NEEDED.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...HEINLEIN
LONG TERM...SALTZMAN
AVIATION...GUERRERO
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
154 AM EDT THU MAY 16 2013
.SYNOPSIS...
A COLD FRONT JUST SOUTH OF THE LAKESHORE WILL PUSH INTO CENTRAL OHIO
TONIGHT AND THEN STALL. THE FRONT WILL LIFT NORTH AS A WARM FRONT
THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
COLD FRONT CURRENTLY SOUTH OF THE LAKESHORE. A COUPLE OF SHOWERS
HAVE POPPED UP JUST SOUTH OF KNOX COUNTY. WILL KEEP THE SLIGHT
CHANCE FOR A SHOWER/TS FROM FINDLAY TO MILLERSBURG. HRRR AND RAP
WANT TO PAINT SOME QPF TONIGHT. WITH BOUNDARY IN THE VICINITY AND
A LITTLE BIT OF ENERGY UPSTREAM...DID NOT WANT A COMPLETELY DRY
FORECAST. FOR TEMPS WENT UPPER 40S TO THE MID 50S. THERE IS ENOUGH
UPSTREAM CLOUDINESS TO GIVE US A VARIABLY CLOUDY OVERNIGHT.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY NIGHT/...
MODELS CONTINUE TO STALL THE FRONT WELL SOUTH OF THE AREA. GFS A
LITTLE SLOWER TODAY MOVING THE FRONT NORTH. EXCEPT FOR THE EXTREME
SW PORTION OF THE FORECAST AREA REMOVED MENTION OF POPS FOR FRIDAY
AND FRIDAY NIGHT. MODELS STILL IN CONFLICT FOR SATURDAY. ECMWF
KEEPS FRONT SOUTH OF THE AREA ON SATURDAY WHILE GFS CONTINUES TO
HAVE THE FRONT ACROSS THE AREA. FOR NOW SEE NO REASON TO START FLIP
FLOPPING FORECASTS THIS FAR OUT WHEN THINGS ARE STILL IN DOUBT. SO
FOR NOW KEPT CHANCE POPS GOING FOR SATURDAY.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
THE RIDGE IS STILL PROGGED TO BUILD ACROSS THE AREA THIS WEEKEND
THROUGH EARLY NEXT WEEK. THE CHANCES OF SHOWERS/STORMS SHOULD
DIMINISH UNDER THE BUILDING RIDGE. CANNOT TOTALLY RULE OUT OUT A
SHOWER OR THUNDERSTORM GIVEN THE OLD FRONTAL BOUNDARY OR SOME
OUTFLOW/MESO BOUNDARY... INCREASING HEAT ETC...BUT FOR THE
MOST PART SUNDAY AND MONDAY SHOULD BE WARM AND MOSTLY RAIN FREE. CUT
BACK ON THE 12 HOUR POP SUNDAY/MONDAY MOSTLY TO 15 TO 25 PERCENT.
THIS WILL BE "SLIGHT CHANCE" IN MOST FORECASTS WHICH DOES NOT SHOW
UP IN MOST OF OUR TEXT FORECASTS (AFTER THE FIRST DAY).
BY THE MIDDLE OF NEXT WEEK THE NEXT FRONT FROM THE WEST SHOULD WORK
INTO THE AREA. IT WILL LIKELY NOT BE IN A HURRY TO MOVE EAST AS A
TROUGH ALOFT IS PROGGED TO BE DEEPENING IN THE MIDDLE OF THE
COUNTRY. WILL HAVE A HIGHER CHANCE OF SHOWERS AND THUNDERSTORMS BY
TUESDAY AND WEDNESDAY. WILL BEGIN TO CUT BACK ON TEMPERATURES BY
NEXT WEDNESDAY GIVEN THE INCREASE IN CLOUDS AND SHOWERS.
FORECAST HIGHS WILL BE ABOVE GUIDANCE GIVEN THE BIG RIDGE AND THE
TIME OF YEAR. HIGHS 75 TO 80 SUNDAY...AROUND 80 OR IN THE LOWER 80S
MONDAY AND TUESDAY...THEN 70S WEDNESDAY. LOWS GENERALLY MID 50S TO
THE LOWER 60S.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
FRONTAL BOUNDARY IS NEARLY STATIONARY ACROSS THE SOUTHERN PORTION
OF THE FORECAST AREA AND THUNDERSTORMS CONTINUE TO DEVELOP ALONG
THE LINE. MANSFIELD WILL BE THE ONLY SITE AFFECTED BY THE
CONVECTION AND SHOULD BE BRIEF.
OTHERWISE...CLEARING WILL WORK INTO THE AREA THROUGH THE REST OF
THE NIGHT INTO TODAY. WINDS SHOULD BE LIGHT AND VARIABLE BECOMING
NORTHEAST BY THE END OF THE PERIOD.
.OUTLOOK... NON-VFR POSSIBLE IN SHOWERS OR THUNDERSTORMS
FRIDAY NIGHT THROUGH SUNDAY.
&&
.MARINE...
THE WINDS AND WAVES DECREASED ON SCHEDULE. WILL LET THE SMALL CRAFT
ADVISORY EXPIRE ON THE EAST END. ONLY MINOR CHANGES MADE TO THE
OVERNIGHT FORECAST.
HIGH PRESSURE WILL SLOWLY BUILD EAST ACROSS THE LAKE FROM THURSDAY
THROUGH THE WEEKEND. TEMPERATURES WILL BE ABOVE NORMAL THROUGH THIS
TIME WITH STABLE CONDITIONS ON THE LAKE. WINDS WILL GENERALLY BE
LESS THAN 15 KNOTS WITH WAVES LESS THAN 2 FEET. LOW PRESSURE WILL
SLOWLY APPROACH THE REGION FROM THE WEST EARLY NEXT WEEK BRINGING
INCREASING CHANCES OF SHOWERS AND THUNDERSTORMS.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...DJB
NEAR TERM...DJB/OUDEMAN
SHORT TERM...DJB
LONG TERM...KOSARIK
AVIATION...LOMBARDY
MARINE...KEC/KIELTYKA
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
601 AM EDT THU MAY 16 2013
.SYNOPSIS...
AN WEST-EAST FRONTAL BOUNDARY ALONG THE MASON DIXON LINE EARLY
THIS MORNING WILL SINK SOUTHWARD INTO THE CENTRAL APPALACHIANS AND
BECOME QUASI-STATIONARY...PIVOTING TO A NW-SE ORIENTATION.
MEANWHILE...HIGH PRESSURE WILL MIGRATE EASTWARD ACROSS
SOUTHEASTERN CANADA WITH ONSHORE FLOW DEVELOPING ACROSS THE MID-
ATLANTIC REGION. THE FRONTAL BOUNDARY WILL SLOWLY PUSH BACK TO THE
NORTH AS A WARM FRONT OVER THE WEEKEND...AND LIFT NORTH OF THE
AREA BY EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
08Z SFC ANALYSIS PLACES QUASI-STATIONARY FRONT FROM SOUTHERN PA
WESTWARD TO SE IOWA. MOST CONVECTIVELY ACTIVE PORTION OF THIS FRONT
IS OVR SE OHIO/SW PA AT 08Z...THE RESULT OF LG SCALE FORCING AHEAD
OF SHORTWAVE MOVING OVR THE E GRT LKS. AS THIS FEATURE TRACKS
EAST...EXPECT THE BEST CHC OF SHRA AND A FEW TSRA TO SHIFT FROM THE
LAUREL HIGHLANDS TO THE LOWER SUSQ VALLEY BY 12Z. LATEST RAP AND
NAMPARA SIMULATED RADAR DATA BOTH INDICATE A SIMILAR SCENARIO
PLAYING OUT EARLY THIS AM.
SHORTWAVE WILL PASS EAST OF THE AREA BY LATE AM...WITH ENOUGH OF A
NWRLY FLOW BEHIND IT TO PUSH THE SFC FRONT JUST SOUTH OF THE MASON
DIXON LINE BY THIS AFTN. DIURNAL HEATING/DESTABILIZATION...COMBINED
WITH APPROACH OF NEXT SHORTWAVE OVR THE GRT LKS...SHOULD CAUSE A NEW
ROUND OF CONVECTION TO FIRE ALONG FRONT JUST SOUTH OF PA THIS AFTN.
WILL MAINTAIN ONLY A SLIGHT CHC ALONG OUR S TIER COUNTIES.
ALTHOUGH TODAY WILL DAWN MCLDY ACROSS SOUTHERN PA...A GOOD DEAL OF
SUNSHINE APPEARS LIKELY EVERYWHERE BY AFTN...AS WNW FLOW DRAWS DRIER
AIR INTO THE STATE. ENS MEAN 8H TEMPS OF ARND 13C SHOULD SUPPORT
HIGH TEMPS FROM THE M70S OVR THE ALLEGHENY PLATEAU...TO THE L80S IN
THE SUSQ VALLEY.
ALL MDL DATA INDICATING HIGH PRES RIDGE AND ASSOC DRY AIR MASS NOSES
SEWRD INTO PA TONIGHT...BRINGING MCLEAR SKIES AND LIGHT WINDS TO ALL
OF CENTRAL PA. THE DRIEST AIR...AS DEPICTED BY GEFS NEGATIVE PWAT
ANOMALIES...REMAIN ACROSS THE NORTHERN HALF OF THE STATE...WHERE
READINGS ARE LIKELY TO DIP INTO THE M/U30S. CAN/T RULE OUT SOME
PATCHY FROST UP THERE...BUT GROWING SEASON HAS NOT OFFICIALLY BEGUN
UP THERE...SO NO ADVISORY NEEDED.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
SFC HIGH PRES WILL SLIDE EWD FROM ONTARIO TO THE MARITIMES BY 12Z
SUNDAY...WITH ONSHORE FLOW DEVELOPING ACRS THE MID-ATLC STATES.
EXPECT SFC RIDGING AND LACK OF ANY SIGNIFICANT MID-UPPER LEVEL
FORCING TO LIMIT PCPN THROUGH MOST OF THE PERIOD. THE HIGHEST POPS
ARE OVER THE SERN ZONES SAT NGT AS AN UPPER LEVEL WAVE DRIFTS EWD
ACRS KY/TN INTO THE CNTRL APPLCHNS AND INTERACTS WITH ONSHORE MSTR
FEED INTERSECTING RETREATING Q-STNRY/WARM FRONT LIFTING NWD OVER
THE MID-ATLC. EXPECT LOW CLOUDS TO DEVELOP FROM SOUTH TO NORTH ON
SAT NGT IN SELY FLOW REGIME. TEMPS WILL BE WARMER ON FRIDAY WITH
MORE SUN.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
GUIDANCE CONTINUES TO TREND COOLER FOR SUNDAY WITH HIGHS IN THE
MID-UPPER 60S...AS MOIST ONSHORE FLOW STRENGTHENS /-2SD 850MB U
WIND ANOMALY IN GEFS/ AND BRINGS EXTENSIVE CLOUD COVER TO THE
REGION. MDL LI PROGS SHOW A CAD PATTERN IN THE LOW-LEVELS AS THE
WARM FRONT PIVOTS AND STALLS ALONG THE ALLEGHENY FRONT. WITH
STABLE CONDITIONS EXPECTED...CHANGED WX TYPE TO LGT RAIN AS
INSTABILITY SHOULD BE LOCATED WEST OF THE MTNS. FOCUS FOR PCPN
INTO MONDAY SHOULD REMAIN SOUTH OF PA OVER THE VA/NC IN CONJCT
WITH UPPER LEVEL WAVE AND MAX PWAT ANOM NR +2SD. HIGHEST POPS ARE
AGAIN OVER THE ERN 1/2 OF THE CWA AS SELY FLOW CONTS TO IMPINGE ON
SLOWLY RETREATING/DIFFUSE N-S WARM FRONT.
THE LG SCALE PATTERN IS FCST TO TURN DECIDEDLY MORE AMPLIFIED NEXT
WEEK...WITH THE MAIN SYNOPTIC FEATURE OF INTEREST BEING AN UPPER
LOW OVER THE NRN PLAINS/UPR MS VLY. H5 HGTS SHOULD RISE DOWNSTREAM
OF THIS SYSTEM...WITH CENTRAL PA LKLY BREAKING INTO THE WARM
SECTOR BY NEXT TUES AS THE PESKY WARM FRONT LIFTS NORTH INTO NEW
ENGLAND. THIS SHOULD AFFORD ONE OR TWO VERY WARM LATE SPRING DAYS
WITH HIGHS 75-80F. THERE IS A HIGH SPREAD BETWEEN THE GFS/ECMWF
CONCERNING THE POTENTIAL UPPER MIDWEST CUT-OFF. THEREFORE UTILIZED
A 50/50 BLEND OF THEIR RESPECTIVE MOS PRODUCTS FOR THE DAY 5-7
FCST.
&&
.AVIATION /10Z THURSDAY THROUGH MONDAY/...
A SLOW-MOVING COLD FRONT MOVING WILL BE ACCOMPANIED BY A ROUND OF
SHRA...AND PERHAPS EVEN AN ISOLATED TSRA...EARLY THIS MORNING
ACROSS THE SOUTHERN PA AIRFIELDS. BASED ON LATEST RADAR
LOOP...MVFR CONDS WILL BE POSSIBLE BTWN 10Z-11Z AT JST/AOO...AFTER
WHICH A RETURN TO VFR CONDS APPEARS LIKELY. AT MDT/LNS...VSBY
REDUCTIONS IN SHRA/FOG COULD LAST UNTIL ARND 13Z.
BY LATE MORNING...THE FRONTAL BOUNDARY SHOULD SHIFT SOUTH OF
PA...RESULTING IN A HIGH DEGREE OF CONFIDENCE IN VFR CONDS ACROSS
THE ENTIRE STATE.
.OUTLOOK...
FRI-SUN...NO SIG WX EXPECTED.
MON...AM LOW CIGS POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...FITZGERALD
SHORT TERM...STEINBUGL
LONG TERM...STEINBUGL
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
547 AM EDT THU MAY 16 2013
.SYNOPSIS...
AN WEST-EAST FRONTAL BOUNDARY ALONG THE MASON DIXON LINE EARLY
THIS MORNING WILL SINK SOUTHWARD INTO THE CENTRAL APPALACHIANS AND
BECOME QUASI-STATIONARY...PIVOTING TO A NW-SE ORIENTATION.
MEANWHILE...HIGH PRESSURE WILL MIGRATE EASTWARD ACROSS
SOUTHEASTERN CANADA WITH ONSHORE FLOW DEVELOPING ACROSS THE MID-
ATLANTIC REGION. THE FRONTAL BOUNDARY WILL SLOWLY PUSH BACK TO THE
NORTH AS A WARM FRONT OVER THE WEEKEND...AND LIFT NORTH OF THE
AREA BY EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
08Z SFC ANALYSIS PLACES QUASI-STATIONARY FRONT FROM SOUTHERN PA
WESTWARD TO SE IOWA. MOST CONVECTIVELY ACTIVE PORTION OF THIS FRONT
IS OVR SE OHIO/SW PA AT 08Z...THE RESULT OF LG SCALE FORCING AHEAD
OF SHORTWAVE MOVING OVR THE E GRT LKS. AS THIS FEATURE TRACKS
EAST...EXPECT THE BEST CHC OF SHRA AND A FEW TSRA TO SHIFT FROM THE
LAUREL HIGHLANDS TO THE LOWER SUSQ VALLEY BY 12Z. LATEST RAP AND
NAMPARA SIMULATED RADAR DATA BOTH INDICATE A SIMILAR SCENARIO
PLAYING OUT EARLY THIS AM.
SHORTWAVE WILL PASS EAST OF THE AREA BY LATE AM...WITH ENOUGH OF A
NWRLY FLOW BEHIND IT TO PUSH THE SFC FRONT JUST SOUTH OF THE MASON
DIXON LINE BY THIS AFTN. DIURNAL HEATING/DESTABILIZATION...COMBINED
WITH APPROACH OF NEXT SHORTWAVE OVR THE GRT LKS...SHOULD CAUSE A NEW
ROUND OF CONVECTION TO FIRE ALONG FRONT JUST SOUTH OF PA THIS AFTN.
WILL MAINTAIN ONLY A SLIGHT CHC ALONG OUR S TIER COUNTIES.
ALTHOUGH TODAY WILL DAWN MCLDY ACROSS SOUTHERN PA...A GOOD DEAL OF
SUNSHINE APPEARS LIKELY EVERYWHERE BY AFTN...AS WNW FLOW DRAWS DRIER
AIR INTO THE STATE. ENS MEAN 8H TEMPS OF ARND 13C SHOULD SUPPORT
HIGH TEMPS FROM THE M70S OVR THE ALLEGHENY PLATEAU...TO THE L80S IN
THE SUSQ VALLEY.
ALL MDL DATA INDICATING HIGH PRES RIDGE AND ASSOC DRY AIR MASS NOSES
SEWRD INTO PA TONIGHT...BRINGING MCLEAR SKIES AND LIGHT WINDS TO ALL
OF CENTRAL PA. THE DRIEST AIR...AS DEPICTED BY GEFS NEGATIVE PWAT
ANOMALIES...REMAIN ACROSS THE NORTHERN HALF OF THE STATE...WHERE
READINGS ARE LIKELY TO DIP INTO THE M/U30S. CAN/T RULE OUT SOME
PATCHY FROST UP THERE...BUT GROWING SEASON HAS NOT OFFICIALLY BEGUN
UP THERE...SO NO ADVISORY NEEDED.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
SFC HIGH PRES WILL SLIDE EWD FROM ONTARIO TO THE MARITIMES BY 12Z
SUNDAY...WITH ONSHORE FLOW DEVELOPING ACRS THE MID-ATLC STATES.
EXPECT SFC RIDGING AND LACK OF ANY SIGNIFICANT MID-UPPER LEVEL
FORCING TO LIMIT PCPN THROUGH MOST OF THE PERIOD. THE HIGHEST POPS
ARE OVER THE SERN ZONES SAT NGT AS AN UPPER LEVEL WAVE DRIFTS EWD
ACRS KY/TN INTO THE CNTRL APPLCHNS AND INTERACTS WITH ONSHORE MSTR
FEED INTERSECTING RETREATING Q-STNRY/WARM FRONT LIFTING NWD OVER
THE MID-ATLC. EXPECT LOW CLOUDS TO DEVELOP FROM SOUTH TO NORTH ON
SAT NGT IN SELY FLOW REGIME. TEMPS WILL BE WARMER ON FRIDAY WITH
MORE SUN.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
GUIDANCE CONTINUES TO TREND COOLER FOR SUNDAY WITH HIGHS IN THE
MID-UPPER 60S...AS MOIST ONSHORE FLOW STRENGTHENS /-2SD 850MB U
WIND ANOMALY IN GEFS/ AND BRINGS EXTENSIVE CLOUD COVER TO THE
REGION. MDL LI PROGS SHOW A CAD PATTERN IN THE LOW-LEVELS AS THE
WARM FRONT PIVOTS AND STALLS ALONG THE ALLEGHENY FRONT. WITH
STABLE CONDITIONS EXPECTED...CHANGED WX TYPE TO LGT RAIN AS
INSTABILITY SHOULD BE LOCATED WEST OF THE MTNS. FOCUS FOR PCPN
INTO MONDAY SHOULD REMAIN SOUTH OF PA OVER THE VA/NC IN CONJCT
WITH UPPER LEVEL WAVE AND MAX PWAT ANOM NR +2SD. HIGHEST POPS ARE
AGAIN OVER THE ERN 1/2 OF THE CWA AS SELY FLOW CONTS TO IMPINGE ON
SLOWLY RETREATING/DIFFUSE N-S WARM FRONT.
THE LG SCALE PATTERN IS FCST TO TURN DECIDEDLY MORE AMPLIFIED NEXT
WEEK...WITH THE MAIN SYNOPTIC FEATURE OF INTEREST BEING AN UPPER
LOW OVER THE NRN PLAINS/UPR MS VLY. H5 HGTS SHOULD RISE DOWNSTREAM
OF THIS SYSTEM...WITH CENTRAL PA LKLY BREAKING INTO THE WARM
SECTOR BY NEXT TUES AS THE PESKY WARM FRONT LIFTS NORTH INTO NEW
ENGLAND. THIS SHOULD AFFORD ONE OR TWO VERY WARM LATE SPRING DAYS
WITH HIGHS 75-80F. THERE IS A HIGH SPREAD BETWEEN THE GFS/ECMWF
CONCERNING THE POTENTIAL UPPER MIDWEST CUT-OFF. THEREFORE UTILIZED
A 50/50 BLEND OF THEIR RESPECTIVE MOS PRODUCTS FOR THE DAY 5-7
FCST.
&&
.AVIATION /09Z THURSDAY THROUGH MONDAY/...
A STALLED FRONTAL BOUNDARY LYING ACROSS SOUTHERN PA WILL PROVIDE
THE FOCUS FOR A FEW SHRA AND EVEN AN ISOLATED TSRA THIS MORNING.
05Z DWPT DEPRESSIONS AND NR TERM MDL DATA SUGGEST MDT AND LNS
WILL LIKELY SEE A BIT OF FOG IN THE 08Z-12Z TIME FRAME. MDL
GUIDANCE SUGGESTS VSBYS WILL GO NO LOWER THAN MVFR. HOWEVER...WOULD
NOT RULE OUT A BRIEF DIP TO IFR AT MDT/LNS...WHERE GROUND REMAINS
WET FROM YESTERDAY/S RAINFALL.
HIGHER DWPT DEPRESSIONS AT JST AND AOO INDICATE THEY WILL LIKELY
REMAIN VFR UNLESS A HEAVY SHRA/TSRA HAPPENS TO OCCUR BEFORE DAWN.
ANY EARLY FOG SHOULD LIFT SHORTLY AFTER SUNRISE. HOWEVER...WILL
STILL HAVE TO CONTEND WITH THE SLIGHT CHC OF A LATE AM SHRA/TSRA
ACROSS THE SOUTHERN AIRFIELDS. BY AFTN...THE FRONTAL BOUNDARY
SHOULD SHIFT SOUTH OF PA...RESULTING IN A HIGH DEGREE OF
CONFIDENCE IN VFR CONDS ACROSS THE ENTIRE STATE.
.OUTLOOK...
FRI-SUN...NO SIG WX EXPECTED.
MON...AM LOW CIGS POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...FITZGERALD
SHORT TERM...STEINBUGL
LONG TERM...STEINBUGL
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1148 PM CDT WED MAY 15 2013
.UPDATE...
UPDATED FORECAST FOR SEVERE THUNDERSTORM WATCH 162
&&
.DISCUSSION...
BOW ECHO OVER C TX SHOULD PROGRESS TOWARDS SE TX TONIGHT INTO THE
EARLY MORNING HOURS. THINK MOMENTUM FROM SYSTEM SHOULD CARRY IT
INTO KCLL/KUTS AREA AROUND 6-8Z. STORM ENVIRONMENT STILL NOT AS
ROBUST AS C TX WITH LIMITED CAPE AND CIN FROM OVERNIGHT
STABILIZATION. MAIN THREAT FROM THE SQUALL LINE WILL BE STRAIGHT
LINE WINDS WITH HAIL AS SECONDARY THREAT. UPDATED FORECAST HAS
BEEN SENT.
39
&&
.PREV DISCUSSION... /ISSUED 934 PM CDT WED MAY 15 2013/
UPDATE...
EVENING FORECAST UPDATE.
DISCUSSION...
MONITORING SEVERE WEATHER OUTBREAK OVER N C TX WITH GREAT
INTEREST. UNFORTUNATELY SAD THAT THERE HAS BEEN SIGNIFICANT
DAMAMGE IN AREAS SW OF DFW METROPLEX. MAIN CONCERN IS THAT THE 12Z
WRF-ARW AND RECENT RUNS OF HRRR TRY TO BRING A LINE OF STORMS INTO
THE NORTHERN PORTIONS OF SE TX LATE TONIGHT INTO TOMORROW MORNING.
FOR NOW DO NOT SEE A LINE OF STORMS FORMING YET AND WILL WATCH FOR
THIS TO HAPPEN. THINK 30 POPS FOR NOW LOOKS ON TRACK FOR NOW.
ENVIRONMENT IS A LOT LESS FAVORABLE FOR SEVERE WEATHER WITH MOST
OF THE AREA CAPPED AND WITH LESS THAN 1000 J/KG OF CAPE. SUSPECT
THAT STORMS WILL WEAKEN AS THEY MOVE TOWARDS SE TX. THAT IS IF A
LINE OF STORMS CAN FORM WHICH GIVEN THE STORM MODE OF ISO
SUPERCELLS...NOT SURE THAT WILL HAPPEN. RIGHT NOW AREAS FROM
COLLEGE STATION TO CROCKETT ARE ON THE EDGE OF BETTER SUPERCELL
ENVIRONMENT BUT IT IS A FINE LINE. POSSIBLE SPC MAY WATCH THESE
AREAS LATER THIS EVENING BUT REMAINS TO BE SEEN SINCE THE STORM
ENVIRONMENT IS NOT AS FAVORABLE. UPDATED FORECAST HAS BEEN SENT.
39
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 68 85 71 89 72 / 50 20 10 10 10
HOUSTON (IAH) 69 84 71 88 71 / 30 20 10 10 10
GALVESTON (GLS) 72 79 73 78 74 / 20 10 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 4 AM CDT THURSDAY FOR
THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA
SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
TO FREEPORT 20 TO 60 NM.
&&
$$
DISCUSSION...39
AREA FORECAST DISCUSSION...CORRECTED
NWS DENVER/BOULDER CO
934 AM MDT THU MAY 16 2013
.CORRECTED AVIATION DISCUSSION.
.UPDATE...SHORT WAVE HAS EXITED THE AREA BUT ENOUGH MOISTURE AND
INSTABILITY BEHIND THE WAVE TO INITIATE A TSTM OVER FORT MORGAN
IN THE LAST FEW MINUTES. OVERALL FORECAST LOOKS ON TRACK. HAVE
NUDGED THE POPS UPWARD IN THE MOUNTAINS THIS AFTN. A FAIRLY
UNIFORM W-NWLY FLOW ALOFT IS PROGGED FOR THIS AFTN....SOME OF
WHICH WILL SHOULD MIX DOWN TO THE SURFACE. CAPES IN THE DENVER
AREA ARE PROGGED TO BE AROUND 400 J/KG WITH THE LOWER LEVELS
DRYING OUT. AS A RESULT...HIGH BASED ISOLATED TSTMS WITH GUSTY
OUTFLOW WINDS TO 35 KTS THE MAIN BIPRODUCT OF THE STORMS. THE PW
VALUES ARE HIGHER FURTHER EAST. EAST OF A STERLING TO AKRON
LINE...AN ISOLATED SEVERE THUNDERSTORM POSSIBLE WITH WIND GUSTS TO
60 MPH AND HAIL TO ONE INCH...ALONG WITH BRIEF HEAVY RAINFALL.
STORM MOTIONS WNWLY AT 10-15 KTS THIS AFTN.
&&
.AVIATION...WEAK BOUNDARY PUSHED THROUGH KDEN EARLIER THIS
MORNING...BUT WINDS BACK TO A S-SWLY COMPONENT. LGT WINDS AND
WEAK SFC PRESSURE GRADIENT MAKE IT HARD FOR MDLS TO KEY IN ON A
PREVAILING WIND. COULD SEE WNWLY WINDS MIX DOWN TO THE SFC WITH
THE LOWER LEVELS DRYING OUT THIS AFTN SO WL GO WITH NW WINDS THIS
AFTN IN THE TAF. SOME BOUNDARY LIKELY LINGERING NEAR OR JUST EAST OF
KDEN SO HAVE INCLUDED VCTS AS WELL WITH THE POTENTIAL FOR HIGH BASED
GUSTY OUTFLOW WINDS THIS AFTN. AS A RESULT MAY ALSO HAVE TO ADD A
TEMPO GROUP WITH GUSTS TO 35 KTS IN THE 21-01Z PERIOD IN THE 18Z
ISSUANCE.
&&
.PREV DISCUSSION... /ISSUED 407 AM MDT THU MAY 16 2013/
SHORT TERM...A WEAK UPPER LEVEL TROUGH WAS MOVING INTO NORTHEAST
COLORADO EARLY THIS MORNING WITH SCATTERED SHOWERS AND ISOLD TSTMS
OVER THE FAR NERN CORNER. THIS WK UPPER LEVEL TROUGH SHOULD EXIT
AREA BY 18Z. BY AFTN THE FLOW ALOFT WILL BE MAINLY ZONAL. LATEST
RAP IS SHOWING CAPES BLO 500 J/KG OVER THE HIGHER TERRAIN AND THE
FRONT RANGE HOWEVER OVER THE FAR NE PLAINS CAPES ARE FCST AOA 1000
J/KG. LATEST RAP SHOWS A WK BNDRY SETTING UP FM A STERLING TO
AKRON LN WHICH COULD ACT AS A FOCUS FOR STRONGER TSTM DEVELOPMENT
BY LATE AFTN INTO THE EARLY EVENING HOURS. OVERALL SHEAR WILL BE
BETTER THIS AFTN IN THIS AREA SO THERE COULD BE AN ISOLD MARGINAL
SVR STORM OR TWO. ELSEWHERE THERE WILL BE SOME WDLY SCT CONVECTION
IN THE MTNS...FOOTHILLS AND OVER THE PALMER DIVIDE. AS FOR HIGHS
850-700 MB TEMPS ARE 2-3 DEGREES WARMER THAN WED SO AFTN HIGHS
SHOULD RISE INTO THE 80S OVER NERN CO. FOR TONIGHT LOOKS LIKE
MOST CONVECTION SHOULD END BY EARLY EVENING AS SEE NOTHING TO KEEP
IT GOING AFTER SUNSET.
LONG TERM...AFTER A DRY AND WARM DAY ON FRIDAY IT LOOKS LIKE THE
REST OF THE FORECAST PERIOD WILL BE COOL AND SOMEWHAT UNSETTLED.
INITIALLY...DRY AND WARM SOUTHWESTERLY FLOW ALOFT WILL PREVAIL
FRIDAY...BRINGING ANOTHER EARLY TASTE OF SUMMER TO THE STATE.
SATURDAY WILL BE A TRANSITIONAL DAY AS AN UPPER TROUGH SETTLES
OVER THE NORTHWEST QUARTER OF THE NATION WITH COLORADO COMING
UNDER THE LEADING EDGE OF THE ADVANCING MOISTURE AND COOLER
TEMPERATURES ALOFT. TROUGHINESS WILL THEN REMAIN OVER THE FORECAST
AREA THROUGH MONDAY NIGHT AND TUESDAY. WEAK DYNAMIC LIFT
ASSOCIATED WITH THE UPPER TROUGH WILL BE OVER THE STATE FOR
SEVERAL DAYS WITH INEVITABLE SHORT WAVE DISTURBANCES MOVING
THROUGH THE TROUGH AT TIMES. ALL THIS SHOULD COMBINE WITH DAILY
HEATING TO PRODUCE ROUNDS OF AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS. AT LOWER LEVELS...IT APPEARS THAT THE SURFACE LOW
WILL REMAIN FAR ENOUGH EAST TO KEEP GULF MOISTURE MORE IN KANSAS
THAN IN EASTERN COLORADO. STILL ENOUGH MOISTURE SHOULD BE AROUND
FOR LIGHT TO MODERATE PRECIPITATION AT TIMES EACH DAY.
TEMPERATURES WILL GET PROGRESSIVELY COOLER THROUGH MONDAY AND THEN
BEGIN WARMING TUESDAY AND WEDNESDAY AS THE UPPER TROUGH FINALLY
MOVES OUT OF STATE AND AN UPPER RIDGE MOVES IN FROM THE WEST.
WITHOUT STRONG DYNAMICS OR ANY APPRECIABLE JET STREAM WINDS...IT
DOES APPEAR THAT THUNDERSTORMS THROUGH THE WEEKEND WILL LACK
ORGANIZATION WHICH WILL LIMIT THE POTENTIAL FOR SEVERE WEATHER. ON
THE OTHER HAND...STORM MOTIONS COULD BE SLOW AT TIMES MAKING
LOCALIZED HEAVY RAIN POSSIBLE...ESPECIALLY IF ANY GULF MOISTURE
SNEAKS IN FROM THE EAST.
AVIATION...COULD SEE AN ISOLD TSTM OR TWO THIS AFTN IN THE
22Z-01Z PERIOD ESPECIALLY SOUTH OF DIA SO FOR NOW WILL KEEP NEXT
TAF VOID OF TSTMS. WINDS EARLY THIS MORNING WERE DRAINAGE. BY MID
TO LATE MORNING THE NAM AND RAP SHOW WINDS RATHER LIGHT AND
VARIABLE AROUND 5 KTS. BY EARLY AFTN THE RAP HAS THE WINDS ESE AND
THEN MORE SSW BY 21Z. MEANWHILE THE NAM HAS THE WINDS BECOMING WNW
BY 18Z AND KEEPS THEM THAT WAY THRU 00Z. AT THIS POINT NOT SURE
WHICH WAY TO TREND THEM. WITH WLY MID LVL FLOW OUTFLOW BOUNDARIES
FM CONVECTION IN THE FOOTHILLS COULD TURN THE WINDS MORE WNW BY
21Z SO WILL FOLLOW NAM FOR NOW. BY EARLY THIS EVENING WINDS SHOULD
GRADUALLY BECOME DRAINAGE AFTER SUNSET.
HYDROLOGY...THERE WILL BE SOME WIDELY SCATTERED HIGHER BASED
THUNDERSTORMS THIS AFTERNOON NR THE BURN AREAS HOWEVER RAINFALL
AMOUNTS SHOULD BE UNDER A QUARTER INCH.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...COOPER
LONG TERM....DANKERS
AVIATION...COOPER
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
929 AM MDT THU MAY 16 2013
.UPDATE...SHORT WAVE HAS EXITED THE AREA BUT ENOUGH MOISTURE AND
INSTABILITY BEHIND THE WAVE TO INITIATE A TSTM OVER FORT MORGAN
IN THE LAST FEW MINUTES. OVERALL FORECAST LOOKS ON TRACK. HAVE
NUDGED THE POPS UPWARD IN THE MOUNTAINS THIS AFTN. A FAIRLY
UNIFORM W-NWLY FLOW ALOFT IS PROGGED FOR THIS AFTN....SOME OF
WHICH WILL SHOULD MIX DOWN TO THE SURFACE. CAPES IN THE DENVER
AREA ARE PROGGED TO BE AROUND 400 J/KG WITH THE LOWER LEVELS
DRYING OUT. AS A RESULT...HIGH BASED ISOLATED TSTMS WITH GUSTY
OUTFLOW WINDS TO 35 KTS THE MAIN BIPRODUCT OF THE STORMS. THE PW
VALUES ARE HIGHER FURTHER EAST. EAST OF A STERLING TO AKRON
LINE...AN ISOLATED SEVERE THUNDERSTORM POSSIBLE WITH WIND GUSTS TO
60 MPH AND HAIL TO ONE INCH...ALONG WITH BRIEF HEAVY RAINFALL.
STORM MOTIONS WNWLY AT 10-15 KTS THIS AFTN.
&&
.AVIATION...WEAK BOUNDARY PUSHED THROUGH KDEN EARLIER THIS
MORNING...BUT WINDS BACK TO A S-SWLY COMPONENT. LGT WINDS AND
WEAK SFC PRESSURE GRADIENT MAKE IT HARD FOR MDLS TO KEY IN ON A
PREVAILING WIND. COULD SEE WNWLY WINDS MIX DOWN TO THE SFC WITH
THE LOWER LEVELS DRYING OUT THIS AFTN SO WL GO WITH NW WINDS THIS
AFTN IN THE TAF. SOME BOUNDARY LIKELY LINGERING NEAR OR JUST EAST
OF KDEN SO HAVE INCLUDED VCTS AS WELL WITH THE POTENTIAL FOR HIGH
BASED GUSTY OUTFLOW WINDS THIS AFTN. AS A RESULT HAVE ADD A TEMPO
GROUP WITH GUSTS TO 35 KTS IN THE 21-01Z PERIOD.
&&
.PREV DISCUSSION... /ISSUED 407 AM MDT THU MAY 16 2013/
SHORT TERM...A WEAK UPPER LEVEL TROUGH WAS MOVING INTO NORTHEAST
COLORADO EARLY THIS MORNING WITH SCATTERED SHOWERS AND ISOLD TSTMS
OVER THE FAR NERN CORNER. THIS WK UPPER LEVEL TROUGH SHOULD EXIT
AREA BY 18Z. BY AFTN THE FLOW ALOFT WILL BE MAINLY ZONAL. LATEST
RAP IS SHOWING CAPES BLO 500 J/KG OVER THE HIGHER TERRAIN AND THE
FRONT RANGE HOWEVER OVER THE FAR NE PLAINS CAPES ARE FCST AOA 1000
J/KG. LATEST RAP SHOWS A WK BNDRY SETTING UP FM A STERLING TO
AKRON LN WHICH COULD ACT AS A FOCUS FOR STRONGER TSTM DEVELOPMENT
BY LATE AFTN INTO THE EARLY EVENING HOURS. OVERALL SHEAR WILL BE
BETTER THIS AFTN IN THIS AREA SO THERE COULD BE AN ISOLD MARGINAL
SVR STORM OR TWO. ELSEWHERE THERE WILL BE SOME WDLY SCT CONVECTION
IN THE MTNS...FOOTHILLS AND OVER THE PALMER DIVIDE. AS FOR HIGHS
850-700 MB TEMPS ARE 2-3 DEGREES WARMER THAN WED SO AFTN HIGHS
SHOULD RISE INTO THE 80S OVER NERN CO. FOR TONIGHT LOOKS LIKE
MOST CONVECTION SHOULD END BY EARLY EVENING AS SEE NOTHING TO KEEP
IT GOING AFTER SUNSET.
LONG TERM...AFTER A DRY AND WARM DAY ON FRIDAY IT LOOKS LIKE THE
REST OF THE FORECAST PERIOD WILL BE COOL AND SOMEWHAT UNSETTLED.
INITIALLY...DRY AND WARM SOUTHWESTERLY FLOW ALOFT WILL PREVAIL
FRIDAY...BRINGING ANOTHER EARLY TASTE OF SUMMER TO THE STATE.
SATURDAY WILL BE A TRANSITIONAL DAY AS AN UPPER TROUGH SETTLES
OVER THE NORTHWEST QUARTER OF THE NATION WITH COLORADO COMING
UNDER THE LEADING EDGE OF THE ADVANCING MOISTURE AND COOLER
TEMPERATURES ALOFT. TROUGHINESS WILL THEN REMAIN OVER THE FORECAST
AREA THROUGH MONDAY NIGHT AND TUESDAY. WEAK DYNAMIC LIFT
ASSOCIATED WITH THE UPPER TROUGH WILL BE OVER THE STATE FOR
SEVERAL DAYS WITH INEVITABLE SHORT WAVE DISTURBANCES MOVING
THROUGH THE TROUGH AT TIMES. ALL THIS SHOULD COMBINE WITH DAILY
HEATING TO PRODUCE ROUNDS OF AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS. AT LOWER LEVELS...IT APPEARS THAT THE SURFACE LOW
WILL REMAIN FAR ENOUGH EAST TO KEEP GULF MOISTURE MORE IN KANSAS
THAN IN EASTERN COLORADO. STILL ENOUGH MOISTURE SHOULD BE AROUND
FOR LIGHT TO MODERATE PRECIPITATION AT TIMES EACH DAY.
TEMPERATURES WILL GET PROGRESSIVELY COOLER THROUGH MONDAY AND THEN
BEGIN WARMING TUESDAY AND WEDNESDAY AS THE UPPER TROUGH FINALLY
MOVES OUT OF STATE AND AN UPPER RIDGE MOVES IN FROM THE WEST.
WITHOUT STRONG DYNAMICS OR ANY APPRECIABLE JET STREAM WINDS...IT
DOES APPEAR THAT THUNDERSTORMS THROUGH THE WEEKEND WILL LACK
ORGANIZATION WHICH WILL LIMIT THE POTENTIAL FOR SEVERE WEATHER. ON
THE OTHER HAND...STORM MOTIONS COULD BE SLOW AT TIMES MAKING
LOCALIZED HEAVY RAIN POSSIBLE...ESPECIALLY IF ANY GULF MOISTURE
SNEAKS IN FROM THE EAST.
AVIATION...COULD SEE AN ISOLD TSTM OR TWO THIS AFTN IN THE
22Z-01Z PERIOD ESPECIALLY SOUTH OF DIA SO FOR NOW WILL KEEP NEXT
TAF VOID OF TSTMS. WINDS EARLY THIS MORNING WERE DRAINAGE. BY MID
TO LATE MORNING THE NAM AND RAP SHOW WINDS RATHER LIGHT AND
VARIABLE AROUND 5 KTS. BY EARLY AFTN THE RAP HAS THE WINDS ESE AND
THEN MORE SSW BY 21Z. MEANWHILE THE NAM HAS THE WINDS BECOMING WNW
BY 18Z AND KEEPS THEM THAT WAY THRU 00Z. AT THIS POINT NOT SURE
WHICH WAY TO TREND THEM. WITH WLY MID LVL FLOW OUTFLOW BOUNDARIES
FM CONVECTION IN THE FOOTHILLS COULD TURN THE WINDS MORE WNW BY
21Z SO WILL FOLLOW NAM FOR NOW. BY EARLY THIS EVENING WINDS SHOULD
GRADUALLY BECOME DRAINAGE AFTER SUNSET.
HYDROLOGY...THERE WILL BE SOME WIDELY SCATTERED HIGHER BASED
THUNDERSTORMS THIS AFTERNOON NR THE BURN AREAS HOWEVER RAINFALL
AMOUNTS SHOULD BE UNDER A QUARTER INCH.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...COOPER
LONG TERM....DANKERS
AVIATION...COOPER
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
407 AM MDT THU MAY 16 2013
.SHORT TERM...A WEAK UPPER LEVEL TROUGH WAS MOVING INTO NORTHEAST
COLORADO EARLY THIS MORNING WITH SCATTERED SHOWERS AND ISOLD TSTMS
OVER THE FAR NERN CORNER. THIS WK UPPER LEVEL TROUGH SHOULD EXIT
AREA BY 18Z. BY AFTN THE FLOW ALOFT WILL BE MAINLY ZONAL. LATEST
RAP IS SHOWING CAPES BLO 500 J/KG OVER THE HIGHER TERRAIN AND THE
FRONT RANGE HOWEVER OVER THE FAR NE PLAINS CAPES ARE FCST AOA 1000
J/KG. LATEST RAP SHOWS A WK BNDRY SETTING UP FM A STERLING TO
AKRON LN WHICH COULD ACT AS A FOCUS FOR STRONGER TSTM DEVELOPMENT
BY LATE AFTN INTO THE EARLY EVENING HOURS. OVERALL SHEAR WILL BE
BETTER THIS AFTN IN THIS AREA SO THERE COULD BE AN ISOLD MARGINAL
SVR STORM OR TWO. ELSEWHERE THERE WILL BE SOME WDLY SCT CONVECTION
IN THE MTNS...FOOTHILLS AND OVER THE PALMER DIVIDE. AS FOR HIGHS
850-700 MB TEMPS ARE 2-3 DEGREES WARMER THAN WED SO AFTN HIGHS
SHOULD RISE INTO THE 80S OVER NERN CO. FOR TONIGHT LOOKS LIKE
MOST CONVECTION SHOULD END BY EARLY EVENING AS SEE NOTHING TO KEEP
IT GOING AFTER SUNSET.
.LONG TERM...AFTER A DRY AND WARM DAY ON FRIDAY IT LOOKS LIKE THE
REST OF THE FORECAST PERIOD WILL BE COOL AND SOMEWHAT UNSETTLED.
INITIALLY...DRY AND WARM SOUTHWESTERLY FLOW ALOFT WILL PREVAIL
FRIDAY...BRINGING ANOTHER EARLY TASTE OF SUMMER TO THE STATE.
SATURDAY WILL BE A TRANSITIONAL DAY AS AN UPPER TROUGH SETTLES
OVER THE NORTHWEST QUARTER OF THE NATION WITH COLORADO COMING
UNDER THE LEADING EDGE OF THE ADVANCING MOISTURE AND COOLER
TEMPERATURES ALOFT. TROUGHINESS WILL THEN REMAIN OVER THE FORECAST
AREA THROUGH MONDAY NIGHT AND TUESDAY. WEAK DYNAMIC LIFT
ASSOCIATED WITH THE UPPER TROUGH WILL BE OVER THE STATE FOR
SEVERAL DAYS WITH INEVITABLE SHORT WAVE DISTURBANCES MOVING
THROUGH THE TROUGH AT TIMES. ALL THIS SHOULD COMBINE WITH DAILY
HEATING TO PRODUCE ROUNDS OF AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS. AT LOWER LEVELS...IT APPEARS THAT THE SURFACE LOW
WILL REMAIN FAR ENOUGH EAST TO KEEP GULF MOISTURE MORE IN KANSAS
THAN IN EASTERN COLORADO. STILL ENOUGH MOISTURE SHOULD BE AROUND
FOR LIGHT TO MODERATE PRECIPITATION AT TIMES EACH DAY.
TEMPERATURES WILL GET PROGRESSIVELY COOLER THROUGH MONDAY AND THEN
BEGIN WARMING TUESDAY AND WEDNESDAY AS THE UPPER TROUGH FINALLY
MOVES OUT OF STATE AND AN UPPER RIDGE MOVES IN FROM THE WEST.
WITHOUT STRONG DYNAMICS OR ANY APPRECIABLE JET STREAM WINDS...IT
DOES APPEAR THAT THUNDERSTORMS THROUGH THE WEEKEND WILL LACK
ORGANIZATION WHICH WILL LIMIT THE POTENTIAL FOR SEVERE WEATHER. ON
THE OTHER HAND...STORM MOTIONS COULD BE SLOW AT TIMES MAKING
LOCALIZED HEAVY RAIN POSSIBLE...ESPECIALLY IF ANY GULF MOISTURE
SNEAKS IN FROM THE EAST.
&&
.AVIATION...COULD SEE AN ISOLD TSTM OR TWO THIS AFTN IN THE
22Z-01Z PERIOD ESPECIALLY SOUTH OF DIA SO FOR NOW WILL KEEP NEXT
TAF VOID OF TSTMS. WINDS EARLY THIS MORNING WERE DRAINAGE. BY MID
TO LATE MORNING THE NAM AND RAP SHOW WINDS RATHER LIGHT AND
VARIABLE AROUND 5 KTS. BY EARLY AFTN THE RAP HAS THE WINDS ESE AND
THEN MORE SSW BY 21Z. MEANWHILE THE NAM HAS THE WINDS BECOMING WNW
BY 18Z AND KEEPS THEM THAT WAY THRU 00Z. AT THIS POINT NOT SURE
WHICH WAY TO TREND THEM. WITH WLY MID LVL FLOW OUTFLOW BOUNDARIES
FM CONVECTION IN THE FOOTHILLS COULD TURN THE WINDS MORE WNW BY
21Z SO WILL FOLLOW NAM FOR NOW. BY EARLY THIS EVENING WINDS SHOULD
GRADUALLY BECOME DRAINAGE AFTER SUNSET.
&&
.HYDROLOGY...THERE WILL BE SOME WIDELY SCATTERED HIGHER BASED
THUNDERSTORMS THIS AFTERNOON NR THE BURN AREAS HOWEVER RAINFALL
AMOUNTS SHOULD BE UNDER A QUARTER INCH.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RPK
LONG TERM....DANKERS
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS JACKSON KY
1046 AM EDT THU MAY 16 2013
.UPDATE...
ISSUED AT 1046 AM EDT THU MAY 16 2013
CONVECTION ASSOCIATED WITH THE SURFACE FRONT OVER OH HAS MADE LITTLE
SOUTHWARD PROGRESS THIS MORNING. HOWEVER...A BOUNDARY FROM SOUTHERN
OH CONVECTION HAS MOVED SOUTH INTO KY...AND THIS IS INTERACTING WITH
ENERGY ROTATING NORTHEAST FROM THE MID LEVEL LOW OVER OK. SHOWERS AND
THUNDERSTORMS HAVE BEEN DEVELOPING FROM SDF EAST TO SOUTH OF LEX.
THE 12Z HRRR IS HANDLING THIS FAIRLY WELL...AND THE 12Z NAM IS ALSO
SHOWING THIS. BASED ON CURRENT ANALYSIS...TRENDS AND LATEST MODEL
GUIDANCE HAVE MADE ADJUSTMENTS TO PRECIPITATION CHANCES FOR TODAY. HAVE
INCREASED COVERAGE IN THE CENTRAL PART OF THE AREA TO SCATTERED WITH
A 30 PERCENT CHANCE AND HAVE DECREASED THE PROBABILITY IN THE FAR
SOUTH FROM 40 PERCENT TO 30 PERCENT. WILL CONTINUE TO CARRY THE
HIGHEST SHOWER AND THUNDERSTORM CHANCES IN THE NORTH.
UPDATE ISSUED AT 857 AM EDT THU MAY 16 2013
CLOUDS HAVE INCREASED QUICKLY THIS MORNING...AND HAVE UPDATED THE
NDFD AND ZFP TO REFLECT THIS. MOSTLY CLOUDY SKIES NOW FORECAST ACROSS
THE ENTIRE AREA FOR TODAY. HRRR IS HANDLING CURRENT CONVECTION FAIRLY
WELL. 11Z HRRR POINTS TOWARDS A NORTH TO SOUTH RAIN PROBABILITY
CHANCE THIS AFTERNOON...WITH BEST CHANCE IN THE NORTH. WILL TAKE A
LOOK AT INCOMING 12Z DATA FOR ANY POSSIBLE UPDATES TO THE RAIN
PROBABILITIES FOR THIS AFTERNOON.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 253 AM EDT THU MAY 16 2013
THERE ARE TWO MAIN INGREDIENTS TO THIS FORECAST WHICH INDIVIDUALLY
AND COLLECTIVELY ADD SOME DIFFICULTY TO THE FORECAST. THERE IS A COLD
FRONT SOUTH OF THE GREAT LAKES WHICH IS SAGGING TO THE SOUTH. THERE
IS ALSO AN UPPER LOW OVER OKLAHOMA EMBEDDED IS A WEAKER SOUTHERLY
STREAM. THESE TWO SYSTEMS ARE BOTH GOING TO BE EFFECTING THE WEATHER
OVER THE AREA OVER THE NEXT TWO DAYS. AT 230 AM THERE WAS A LINE OF
SHOWER AND THUNDERSTORMS WHICH EXTENDED FROM SOUTHWEST PENNSYLVANIA AND
THEN PASSED SOUTH OF COLUMBUS AND THEN ACROSS DAYTON. THIS SYSTEM
WILL BE SAGGING TO THE SOUTH. THE BIG QUESTION IS HOW FAR SOUTH WILL
THE FRONT MOVE. THE NAM STALLS THIS FRONT OUT ALONG THE OHIO RIVER
VALLEY. AS A RESULT...KEPT THE BEST CHANCE FOR RAIN TODAY AND
TONIGHT NORTH OF I 64 IN THE BLUEGRASS. THE MODELS ARE ALSO
GENERATING SOME ENERGY OUT AHEAD OF THE UPPER LOW WHICH WILL BE
MOVING TO THE EAST THE AREA SOUTH OF I 64 WILL BE IN THE GENERALLY
UNSTABLE WARM SECTOR TODAY AND TONIGHT WITH SOME ENERGY SPINNING
AROUND THE UPPER LOW WHICH MAY MOVE INTO THE AREA LATER TODAY. THIS
IS MOST LIKELY GOING TO EFFECT THE AREA SOUTH OF THE HAL ROGERS
PARKWAY. SO THERE IS A SLOT ACROSS THE CENTRAL PORTION OF EASTERN
KENTUCKY WHICH SHOULD BE SOUTH OF THE INFLUENCE OF THE FRONT AND
NORTH OF THE INFLUENCE OF THE UPPER LOW. THE ONE THING THAT IS A BIT
OF A WILD CARD IS IF THE THUNDERSTORMS TO THE NORTH ARE ABLE TO
CREATE A COLD POOL TODAY WHICH PROPAGATES SOUTH ACROSS EASTERN
KENTUCKY. THE NAM BUFFER SOUNDING HAS A LIFTED INDEX OF AROUND -5
THIS AFTERNOON...SO IF A COLD POOL DOES MOVE INTO THE AREA...THERE
WILL BE PLENTY OF INSTABILITY TO KEEP IT GOING. THE SCENARIO IS NOT
IN THE FORECAST...HOWEVER BEARS WATCHING.THERE SHOULD BE PLENTY OF
CLOUDS TODAY...HOWEVER THE LOWER LAYERS ARE FAIRLY DRY AND IT SHOULD
TAKE A WHILE TO BE ABLE TO MOISTEN THEM UP ENOUGH FOR THE RAIN TO
REACH THE GROUND. THE TEMPERATURES WILL BE SO DEPENDENT ON HOW
EXTENSIVE THE SHOWERS WILL BE TODAY. WENT A BIT WARMER THAN THE MODEL
CONSENSUS AND BLENDED CLOSER TO THE WARMER NAM MOS FOR TODAY AND
TOMORROW.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 253 AM EDT THU MAY 16 2013
MODE LS ARE IN FAIR AGREEMENT...BETTER WITH RELATIVELY SLOW BUT
PROGRESSIVE UPPER AIR PATTERN THAN WITH SURFACE FEATURES. EXTENDED
STARTS OUT WITH AN OPEN WAVE TRACKING EASTWARD ACROSS THE OHIO/TN
VALLEY REGIONS THROUGH THE WEEKEND. SHORTWAVE RIDGE THEN TRANSITS
THE REGION MONDAY BEFORE SLOW MOVING LOW PRESSURE SYSTEM OVER THE
NORTH CENTRAL PLAINS SHIFTS INTO THE MIDWEST...OR GREAT LAKES BY THE
END OF THE FORECAST WINDOW. WE FALL UNDER A SOUTHWEST FLOW REGIME
ALOFT DURING THE INTERIM. ECMWF...WITH SUPPORT FROM THE CANADIAN
APPEARS MORE ORGANIZED AND FURTHER SOUTH WITH THE UPPER LOW MOVING
OUT OF THE PLAINS AND INTO THE MIDWEST VERSUS THE GFS WHICH KEEPS
THE UPPER LOW UP OVER THE NORTHERN TIER. MODELS DIVERGE EVEN MORE
SIGNIFICANTLY JUST BEYOND THE END OF THE FORECAST PERIOD. TENDENCY
IS TO LEAN TOWARDS THE TYPICALLY MORE ACCURATE...RELIABLE ECMWF WITH
RESPECT TO THE EVOLUTION OF THE UPPER AIR PATTERN.
AT THE SURFACE...AGAIN MODELS DIFFER CONSIDERABLY ON THE EVENTUAL
POSITION SOUTHERN EXTENT OF SURFACE COLD FRONTAL BOUNDARY ACROSS THE
OHIO VALLEY EARLY IN THE FORECAST. THE NAM/GFS BRINGS THE BOUNDARY
AS FAR SOUTH AS AN IND TO DAY LINE LATE THIS AFTERNOON AND/OR EARLY
FRIDAY MORNING RESPECTIVELY. THE ECMWF BRINGS THE BOUNDARY SOUTHWARD
TO BETWEEN DAY AND CVG BY EARLY SATURDAY MORNING...APPARENTLY WITH
SUPPORT FROM THE UPPER LEVEL WAVE THAT PUSHES THROUGH THE REGION.
END RESULT IS THAT THE BOUNDARY NEVER REALLY SEEMS TO MAKE IT AS FAR
SOUTH AS THE OHIO RIVER...IN A TRUE SUMMERTIME LIKE FASHION. THIS
DOES NOT BODE WELL FOR THE OPPORTUNITY OF RAIN UNLESS CONVECTION
ALONG THE FRONTAL BOUNDARY BECOMES MORE ORGANIZED AND MANAGES TO
MAKE A SURGE SOUTHWARD INTO OUR AREA. BEST OPPORTUNITY FOR THIS...
OR JUST SHOWER AND THUNDERSTORM ACTIVITY IN GENERAL WILL COME AS THE
UPPER LEVEL WAVE OR DISTURBANCE GRADUALLY SHIFTS THROUGH THE REGION
SATURDAY AND SUNDAY. TRENDED DRIER SUNDAY NIGHT THROUGH MONDAY NIGHT
WITH UPPER LEVEL RIDGING BUILDING INTO THE AREA. THREAT OF SHOWERS
AND THUNDERSTORMS INCREASE AGAIN TOWARDS THE END OF THE FORECAST
WINDOW...TUESDAY NIGHT AND/OR WEDNESDAY AND BEYOND AS SYSTEM MORE
THAN LIKELY MAKES A MOVE TOWARDS OUR AREA OUT OF THE NORTH CENTRAL
PLAINS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 725 AM EDT THU MAY 16 2013
VFR CONDITIONS WILL HOLD THROUGH THE TAF FORECAST PERIOD. A THREAT
OF THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON WITH THUNDERSTORMS
MOVING FROM THE NORTH IN THE JKL AREA AND FROM THE SOUTH FOR LOZ AND
SME. THERE IS ONLY AND SLIGHT CHANCE AT JKL AND A CHANCE AT SME AND
LOZ. THERE IS TOO MUCH UNCERTAINTY TO GO WITH A PREVAILING
THUNDERSTORM GROUP AS THE THUNDERSTORMS COULD STAY NORTH OR SOUTH AND
MAY NOT IMPACT THE TAF SITES.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...JJ
LONG TERM...RAY
AVIATION...JJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
857 AM EDT THU MAY 16 2013
.UPDATE...
ISSUED AT 857 AM EDT THU MAY 16 2013
CLOUDS HAVE INCREASED QUICKLY THIS MORNING...AND HAVE UPDATED THE
NDFD AND ZFP TO REFLECT THIS. MOSTLY CLOUDY SKIES NOW FORECAST ACROSS
THE ENTIRE AREA FOR TODAY. HRRR IS HANDLING CURRENT CONVECTION FAIRLY
WELL. 11Z HRRR POINTS TOWARDS A NORTH TO SOUTH RAIN PROBABILITY
CHANCE THIS AFTERNOON...WITH BEST CHANCE IN THE NORTH. WILL TAKE A
LOOK AT INCOMING 12Z DATA FOR ANY POSSIBLE UPDATES TO THE RAIN
PROBABILITIES FOR THIS AFTERNOON.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 253 AM EDT THU MAY 16 2013
THERE ARE TWO MAIN INGREDIENTS TO THIS FORECAST WHICH INDIVIDUALLY
AND COLLECTIVELY ADD SOME DIFFICULTY TO THE FORECAST. THERE IS A COLD
FRONT SOUTH OF THE GREAT LAKES WHICH IS SAGGING TO THE SOUTH. THERE
IS ALSO AN UPPER LOW OVER OKLAHOMA EMBEDDED IS A WEAKER SOUTHERLY
STREAM. THESE TWO SYSTEMS ARE BOTH GOING TO BE EFFECTING THE WEATHER
OVER THE AREA OVER THE NEXT TWO DAYS. AT 230 AM THERE WAS A LINE OF
SHOWER AND THUNDERSTORMS WHICH EXTENDED FROM SOUTHWEST PENNSYLVANIA AND
THEN PASSED SOUTH OF COLUMBUS AND THEN ACROSS DAYTON. THIS SYSTEM
WILL BE SAGGING TO THE SOUTH. THE BIG QUESTION IS HOW FAR SOUTH WILL
THE FRONT MOVE. THE NAM STALLS THIS FRONT OUT ALONG THE OHIO RIVER
VALLEY. AS A RESULT...KEPT THE BEST CHANCE FOR RAIN TODAY AND
TONIGHT NORTH OF I 64 IN THE BLUEGRASS. THE MODELS ARE ALSO
GENERATING SOME ENERGY OUT AHEAD OF THE UPPER LOW WHICH WILL BE
MOVING TO THE EAST THE AREA SOUTH OF I 64 WILL BE IN THE GENERALLY
UNSTABLE WARM SECTOR TODAY AND TONIGHT WITH SOME ENERGY SPINNING
AROUND THE UPPER LOW WHICH MAY MOVE INTO THE AREA LATER TODAY. THIS
IS MOST LIKELY GOING TO EFFECT THE AREA SOUTH OF THE HAL ROGERS
PARKWAY. SO THERE IS A SLOT ACROSS THE CENTRAL PORTION OF EASTERN
KENTUCKY WHICH SHOULD BE SOUTH OF THE INFLUENCE OF THE FRONT AND
NORTH OF THE INFLUENCE OF THE UPPER LOW. THE ONE THING THAT IS A BIT
OF A WILD CARD IS IF THE THUNDERSTORMS TO THE NORTH ARE ABLE TO
CREATE A COLD POOL TODAY WHICH PROPAGATES SOUTH ACROSS EASTERN
KENTUCKY. THE NAM BUFFER SOUNDING HAS A LIFTED INDEX OF AROUND -5
THIS AFTERNOON...SO IF A COLD POOL DOES MOVE INTO THE AREA...THERE
WILL BE PLENTY OF INSTABILITY TO KEEP IT GOING. THE SCENARIO IS NOT
IN THE FORECAST...HOWEVER BEARS WATCHING.THERE SHOULD BE PLENTY OF
CLOUDS TODAY...HOWEVER THE LOWER LAYERS ARE FAIRLY DRY AND IT SHOULD
TAKE A WHILE TO BE ABLE TO MOISTEN THEM UP ENOUGH FOR THE RAIN TO
REACH THE GROUND. THE TEMPERATURES WILL BE SO DEPENDENT ON HOW
EXTENSIVE THE SHOWERS WILL BE TODAY. WENT A BIT WARMER THAN THE MODEL
CONSENSUS AND BLENDED CLOSER TO THE WARMER NAM MOS FOR TODAY AND
TOMORROW.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 253 AM EDT THU MAY 16 2013
MODE LS ARE IN FAIR AGREEMENT...BETTER WITH RELATIVELY SLOW BUT
PROGRESSIVE UPPER AIR PATTERN THAN WITH SURFACE FEATURES. EXTENDED
STARTS OUT WITH AN OPEN WAVE TRACKING EASTWARD ACROSS THE OHIO/TN
VALLEY REGIONS THROUGH THE WEEKEND. SHORTWAVE RIDGE THEN TRANSITS
THE REGION MONDAY BEFORE SLOW MOVING LOW PRESSURE SYSTEM OVER THE
NORTH CENTRAL PLAINS SHIFTS INTO THE MIDWEST...OR GREAT LAKES BY THE
END OF THE FORECAST WINDOW. WE FALL UNDER A SOUTHWEST FLOW REGIME
ALOFT DURING THE INTERIM. ECMWF...WITH SUPPORT FROM THE CANADIAN
APPEARS MORE ORGANIZED AND FURTHER SOUTH WITH THE UPPER LOW MOVING
OUT OF THE PLAINS AND INTO THE MIDWEST VERSUS THE GFS WHICH KEEPS
THE UPPER LOW UP OVER THE NORTHERN TIER. MODELS DIVERGE EVEN MORE
SIGNIFICANTLY JUST BEYOND THE END OF THE FORECAST PERIOD. TENDENCY
IS TO LEAN TOWARDS THE TYPICALLY MORE ACCURATE...RELIABLE ECMWF WITH
RESPECT TO THE EVOLUTION OF THE UPPER AIR PATTERN.
AT THE SURFACE...AGAIN MODELS DIFFER CONSIDERABLY ON THE EVENTUAL
POSITION SOUTHERN EXTENT OF SURFACE COLD FRONTAL BOUNDARY ACROSS THE
OHIO VALLEY EARLY IN THE FORECAST. THE NAM/GFS BRINGS THE BOUNDARY
AS FAR SOUTH AS AN IND TO DAY LINE LATE THIS AFTERNOON AND/OR EARLY
FRIDAY MORNING RESPECTIVELY. THE ECMWF BRINGS THE BOUNDARY SOUTHWARD
TO BETWEEN DAY AND CVG BY EARLY SATURDAY MORNING...APPARENTLY WITH
SUPPORT FROM THE UPPER LEVEL WAVE THAT PUSHES THROUGH THE REGION.
END RESULT IS THAT THE BOUNDARY NEVER REALLY SEEMS TO MAKE IT AS FAR
SOUTH AS THE OHIO RIVER...IN A TRUE SUMMERTIME LIKE FASHION. THIS
DOES NOT BODE WELL FOR THE OPPORTUNITY OF RAIN UNLESS CONVECTION
ALONG THE FRONTAL BOUNDARY BECOMES MORE ORGANIZED AND MANAGES TO
MAKE A SURGE SOUTHWARD INTO OUR AREA. BEST OPPORTUNITY FOR THIS...
OR JUST SHOWER AND THUNDERSTORM ACTIVITY IN GENERAL WILL COME AS THE
UPPER LEVEL WAVE OR DISTURBANCE GRADUALLY SHIFTS THROUGH THE REGION
SATURDAY AND SUNDAY. TRENDED DRIER SUNDAY NIGHT THROUGH MONDAY NIGHT
WITH UPPER LEVEL RIDGING BUILDING INTO THE AREA. THREAT OF SHOWERS
AND THUNDERSTORMS INCREASE AGAIN TOWARDS THE END OF THE FORECAST
WINDOW...TUESDAY NIGHT AND/OR WEDNESDAY AND BEYOND AS SYSTEM MORE
THAN LIKELY MAKES A MOVE TOWARDS OUR AREA OUT OF THE NORTH CENTRAL
PLAINS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 725 AM EDT THU MAY 16 2013
VFR CONDITIONS WILL HOLD THROUGH THE TAF FORECAST PERIOD. A THREAT
OF THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON WITH THUNDERSTORMS
MOVING FROM THE NORTH IN THE JKL AREA AND FROM THE SOUTH FOR LOZ AND
SME. THERE IS ONLY AND SLIGHT CHANCE AT JKL AND A CHANCE AT SME AND
LOZ. THERE IS TOO MUCH UNCERTAINTY TO GO WITH A PREVAILING
THUNDERSTORM GROUP AS THE THUNDERSTORMS COULD STAY NORTH OR SOUTH AND
MAY NOT IMPACT THE TAF SITES.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...JJ
LONG TERM...RAY
AVIATION...JJ
AREA FORECAST DISCUSSION
NWS GAYLORD MI
951 AM EDT THU MAY 16 2013
.SYNOPSIS...
ISSUED AT 353 AM EDT THU MAY 16 2013
HIGH PRESSURE WILL GRADUALLY BUILD FROM HUDSON BAY INTO NORTHERN
MICHIGAN THROUGH THE WEEKEND. THIS WEATHER PATTERN PROVIDE PLENTY OF
SUNSHINE AND WARM TEMPERATURES EACH DAY...WHILE ALSO DELIVERING
CLEAR AND CHILLY NIGHTS. OUR NEXT CHANCE FOR RAIN WILL WAIT UNTIL
EARLY NEXT WEEK...AS LOW PRESSURE TAKES SHAPE ACROSS THE WESTERN
LAKES.
&&
.UPDATE...
ISSUED AT 951 AM EDT THU MAY 16 2013
ANOTHER QUIET MORNING ACROSS THE NORTH WOODS...ALTHOUGH NOT WITHOUT
AT LEAST A FEW FORECAST CHALLENGES. BAND OF ACCAS ALONG CORRIDOR OF
IMPRESSIVE H8-H7 LAPSE RATES CONTINUES TO SPILL INTO FAR SOUTHWEST
SECTIONS OF THE AREA...AND SHOULD CONTINUE TO DO SO FOR THE NEXT
COUPLE HOURS. MUCH FURTHER NORTH...EXTENSIVE AREA OF STRATUS
CONTINUES TO SAG SOUTH AROUND BACKSIDE OF QUEBEC CENTERED LOW
PRESSURE. DIURNAL TRENDS AND DOWNSLOPING STARTING TO TAKE ITS
TOLL...WITH NOTABLE THINNING ALONG ITS SOUTHERN FLANK. STILL APPEARS
SOME OF THIS MAY SNEAK INTO EASTERN UPPER MICHIGAN...WITH ADDED
MOISTURE PERHAPS ENTICING A DIURNALLY DRIVEN STRATO-CU RESPONSE.
OTHERWISE...A DRY AND MOSTLY SUNNY DAY IS EXPECTED ACROSS THE AREA.
ONTO FIRE WEATHER CONCERNS: SECONDARY WEAK COLD FRONT HAS EXITED
SOUTH OF THE AREA...WHICH SHOULD ALLOW AFTERNOON HIGHS TO FALL JUST
SHORT OF RED FLAG CRITERIA (ESSENTIALLY...A FEW DEGREES COOLER THAN
THOSE OBSERVED YESTERDAY). WINDS AND RH VALUES...HOWEVER...EXPECTED
TO MAKE A RUN AT CRITICAL LEVELS. CORE OF GUSTY NORTHWEST WINDS (15
TO 25 MPH) EXPECTED ACROSS NORTHEAST LOWER...ESPECIALLY THROUGH
EARLY AFTERNOON. REGIONAL 12Z SOUNDING ANALYSIS AND BACKWARD
TRAJECTORY RAP GUIDANCE BOTH SUPPORT DEWPOINTS MIXING OUT INTO THE
LOWER 30S (ISOLATED UPPER 20S) THROUGH THIS AFTERNOON...PRODUCING RH
READINGS WELL BELOW 30 PERCENT ACROSS A GOOD PORTION OF INTERIOR
NORTHERN LOWER MICHIGAN. WHILE A ROGUE REG FLAG OBSERVATION OR TWO
MORE THAN EXPECTED...ESPECIALLY ACROSS THE HURON NATION FOREST
AREA...THESE SHOULD BE MORE THAN EXCEPTION THAN THE RULE...AND NOT
WORTHY OF ANY SPECIFIC HEADLINE. WILL CONTINUE TO MONITOR.
UPDATE ISSUED AT 618 AM EDT THU MAY 16 2013
NARROW LINE OF MID CLOUD PRESSING INTO NRN LOWER MICHIGAN...BUT
HAS BEEN THINNING OUT CONSIDERABLY AND NOT LIKELY TO HAVE MUCH OF
AN IMPACT ON SKY COVER THIS MORNING. TO THE NORTH...STRATUS
SLOWLY SAGGING SOUTHWARD INTO LAKE SUPERIOR WITH SHALLOW COLD
ADVECTION BEHIND THE WEAK FRONT THAT IS DROPPING THROUGH THE
REGION. NOT ENTIRELY CLEAR JUST HOW MUCH OF THE STRATUS WILL GET
INTO THE U.P. AND SUSPECT A GOOD PART WILL MIX OUT WITH DAYTIME
HEATING. BUT HAVE NUDGED UP SKY COVER (PARTLY SUNNY) FOR EASTERN
UPPER MICHIGAN LATER TODAY ACCORDINGLY.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 353 AM EDT THU MAY 16 2013
OVERVIEW: FAIRLY PROGRESSIVE FLOW PATTERN ACROSS THE CONUS WITH LOW
AMPLITUDE TROUGHINESS IN THE EASTERN GREAT LAKES INTO NEW ENGLAND
AND LOW AMPLITUDE RIDGING ADVANCING THROUGH THE PLAINS. PATTERN
EXPECTED TO AMPLIFY OVER THE NEXT SEVERAL DAYS WITH RIDGING BUILDING
THROUGH THE MIDWEST AND GREAT LAKES HEADING INTO THE WEEKEND...
SIGNALING WARMER AND RAIN-FREE DAYS AHEAD.
ON THE SMALLER SCALE...LOW PRESSURE SYSTEM IS LOCATED OVER WESTERN
QUEBEC WITH A SUBTLE FRONT CURVING BACK ACROSS THE NRN LAKES/SRN
ONTARIO REGION. FRONT IS FORECAST SAG DOWN INTO LOWER MICHIGAN TODAY
RESULTING IN SUBTLE COOLING. SO TAKE YESTERDAYS HIGHS AND TRIM OFF A
FEW DEGREES...THAT SHOULD YIELD A DECENT RESULT. NO SENSIBLE WEATHER
OCCURRING OR EXPECTED TO OCCUR WITH THE FRONT ALTHOUGH THERE IS ONE
BATCH OF MID CLOUD AND SPOTTY ELEVATED RADAR RETURNS ACROSS NRN
WISCONSIN ASSOCIATED WITH POCKET OF STEEP LOW-MID LEVEL LAPSE RATES
THAT WILL SLIDE INTO LOWER MICHIGAN TODAY. IN ADDITION...CLOUD COVER
ACROSS ONTARIO BEHIND THE FRONT MAY MAKE A RUN TOWARD EASTERN UPPER
MICHIGAN BEYOND THE FRONT THIS AFTERNOON. OVERALL...EXPECT PARTLY
CLOUDY TO MOSTLY SUNNY SKIES.
FIRE WEATHER CONCERNS...DRY ANTECEDENT CONDITIONS ALREADY IN PLACE
AND FORECAST SOUNDINGS ONCE AGAIN SUGGEST THE POTENTIAL FOR SFC
DEWPOINTS TO DROP OFF THIS AFTERNOON AFTER HEATING/MIXING TAPS VERY
DRY AIR ALOFT. LOW 30S DEWPOINTS PROBABLY EASILY ATTAINABLE...WITH
EVEN LOW VALUES POSSIBLE IF WE MIX DEEP ENOUGH. THIS WILL RESULT IN
MIN AFTERNOON RH VALUES ACROSS INLAND NRN LOWER MICHIGAN DIPPING
BELOW 25 PERCENT. HOWEVER...TEMPS WILL LARGELY REMAIN BELOW RED FLAG
CRITERIA AND WINDS TODAY WILL NOT BE NEARLY AS GUSTY AS WEDNESDAY.
NO HEADLINES...BUT WILL CONTINUE TO MENTION AN ELEVATED FIRE DANGER
THIS AFTERNOON/EVENING IN TH HAZARDOUS WEATHER OUTLOOK.
TONIGHT...MAINLY CLEAR SKIES/LIGHTER WINDS AND LOW DEWPOINTS WILL
ALLOW TEMPS TO DROP INTO THE 30S FOR MOST AREAS...WITH SOME FROST A
POSSIBILITY AS WELL. DONT EXPECT WIDESPREAD FREEZING CONDITIONS...
BUT DAY SHIFT MAY NEED TO CONSIDER FROST ADVISORY POSSIBILITIES.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 353 AM EDT THU MAY 16 2013
QUIET AND DOWNRIGHT SPECTACULAR LATE SPRING WEATHER REMAINS ON TAP
AS WE WRAP UP THE WORK WEEK AND HEAD THROUGH THE WEEKEND...WITH
REALLY NO MAJOR CONCERNS FORESEEN THROUGH SUNDAY. WHAT HAPPENS
THEREAFTER IS A BIT MORE IN QUESTION...BUT SIGNS CONTINUE TO POINT
TOWARD INCREASING PRECIPITATION CHANCES SOMETIME DURING THE FIRST
HALF OF NEXT WEEK. THE WEATHER PATTERN THROUGH THE WEEKEND IS A
QUIET ONE FOR NORTHERN MICHIGAN...FEATURING A TRANSITION FROM A
RATHER FLAT FLOW ACROSS THE NORTHERN TIER...TOWARD ONE OF AMPLIFIED
UPPER RIDGING BUILDING ACROSS THE WESTERN LAKES BY SUNDAY...
DOWNSTREAM OF RATHER SHARP TROUGH AMPLIFICATION TAKING SHAPE OVER
THE ROCKIES AND EVENTUALLY PLAINS/MISSISSIPPI VALLEY EARLY NEXT
WEEK. SAID PATTERN WILL ALSO FORCE A RATHER PRONOUNCED AREA OF MID
LEVEL CONFLUENCE ACROSS MUCH OF EASTERN CANADA WITH TIME...HELPING
DRIVE LOW LEVEL RIDGING FROM HUDSON BAY THIS WEEKEND INTO SOUTHERN
NEWFOUNDLAND BY EARLY NEXT WEEK.
LOOKING AT A FEW SPECIFICS...JUST NOT TERRIBLY EXCITED BY ANY PRECIP
CHANCES THROUGH THE WEEKEND...AS LOW LEVEL RIDGING DOMINATES WHILE
MID LEVEL HEIGHTS GRADUALLY BUILD WITH TIME. ANY MAJOR PRECIP THREAT
SHOULD BE CONFINED ACROSS THE OHIO AND MID MISSISSIPPI VALLEYS ALONG
A STALLED FRONTAL BOUNDARY (NEAR ITS CLIMO-FAVORED LOCATION THIS
TIME OF YEAR). JUST NOT BUYING INTO NAM/GFS DEPICTION OF ELEVATED
CONVECTION FIRING THIS FAR NORTH LATER FRIDAY NIGHT INTO SATURDAY...
AS THIS APPEARS TO BE TIED TO ERRONEOUS MOISTURE TRANSPORT NORTHWARD
(THIS IS A BIG PROBLEM SO FAR THIS YEAR). IN ADDITION...THE BEST
LOWER LEVEL CONVERGENCE LOOKS TO RESIDE WELL NORTHWEST OF THE AREA
ALONG AN ELEVATED WARM FRONT THROUGH WESTERN ONTARIO...WHILE A
PRONOUNCED SUB-800MB DRY WEDGE DOMINATES NORTHERN MICHIGAN. AS
SUCH...REALLY LIKE OUR CALL TO GO DRY AND WILL MAINTAIN...WITH
PERHAPS JUST A LITTLE INCREASE IN SOME MID OR HIGH CLOUDS EXPECTED.
HIGHS SHOULD WARM WELL INTO THE 60S AND 70S ONCE AGAIN...COOLEST
NEAR THE LAKESHORES WHERE LAKE BREEZE DEVELOPMENT IS LIKELY IN A
WEAK GRADIENT REGIME...ESPECIALLY FRIDAY AND SATURDAY. NIGHTS
CONTINUE TO LOOK COOL AND QUITE COMFORTABLE...AND GIVEN THE SETUP
WITH RESPECTABLE MIXING OUT OF DEW POINTS EACH AFTERNOON AND WEAK
WIND FIELDS...WILL UNDERCUT GUIDANCE NUMBERS...ESPECIALLY FRIDAY
NIGHT WITH SOME LOWER 30S POSSIBLE FOR THE USUAL COOL SPOTS ONCE
AGAIN.
THEREAFTER...CONFIDENCE CONTINUES TO BE ON THE LOW SIDE EARLY NEXT
WEEK REGARDING THE EVOLUTION OF PRECIP CHANCES ACROSS THE AREA.
LATEST GUIDANCE STILL SUGGESTING GRADUAL CLOSED LOW DEVELOPMENT OFF
TO OUR WEST ACROSS THE CENTRAL OR NORTHERN PLAINS. WHILE THE OVERALL
SPECIFICS AREN`T KNOWN JUST YET...PRECIP CHANCES WILL BE ON THE
INCREASE AS AN ELEVATED WARM FRONT EVENTUALLY WORKS NORTH THROUGH
THE AREA...FOLLOWED BY A SURFACE WARM FRONT...ALL WHILE INCREASING
DIFLUENCE ALOFT WORKS IN TANDEM WITH STRENGTHENING RETURN FLOW WITH
A WIDE OPEN GULF. IN FACT...SHOULD THINGS SET UP AS CURRENT MODELED
(THEY RARELY DO)...COULD SEE THIS BEING A HEAVY RAIN SETUP SOMEWHERE
NEARBY. OTHERWISE...TEMPS ARE QUITE TRICKY IN THIS SETUP...WITH THE
POTENTIAL FOR SOME SNEAKY VERY WARM READINGS (WELL INTO THE 80S?) AS
PRONOUNCED THERMAL RIDGING RIDES NORTH INTO THE AREA...BUT ALSO THE
CHANCE FOR RAIN-COOLED 60S PENDING THE EXACT EVOLUTION OF ANY
PRECIP. WILL CONTINUE TO SPLIT THE DIFFERENCE AT THIS POINT...BUT
WITH A NOTABLE TREND TOWARD MUCH MORE HUMID CONDITIONS TOWARD
TUESDAY AND WEDNESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 618 AM EDT THU MAY 16 2013
SOLID VFR CONDITIONS ANTICIPATED THROUGH THE TAF PERIOD. WINDS
WILL VEER NORTHERLY THIS MORNING WITH SOME GUSTINESS AROUND 20
KNOTS...ESPECIALLY AT PLN AND APN. WINDS DIMINISH TONIGHT AND FOR
FRIDAY.
&&
.MARINE...
ISSUED AT 353 AM EDT THU MAY 16 2013
NORTHWEST WINDS WILL PREVAIL TODAY WITH SOME GUSTINESS...ALTHOUGH
GUSTS AND WAVES ARE EXPECTED TO REMAIN LARGELY BELOW SMALL CRAFT
CRITERIA. WINDS GO LIGHT TONIGHT AND REMAIN LIGHT THROUGH FRIDAY
NIGHT.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...MB
SYNOPSIS...DL
SHORT TERM...BA
LONG TERM...DL
AVIATION...BA
MARINE...BA
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1037 AM EDT THU MAY 16 2013
.SYNOPSIS...
WEAK HIGH PRESSURE WILL CONTROL OUR WEATHER THROUGH SATURDAY,
BRINGING DRY CONDITIONS AND MILD DAYTIME TEMPERATURES TO NEW YORK
AND PENNSYLVANIA.
&&
.NEAR TERM /THROUGH TONIGHT/...
1030 AM UPDATE...
FORECAST UPDATED TO LOWER DEWPOINTS FURTHER BELOW GUIDANCE
VALUES /AS WAS ALREADY BECOME EVIDENT/...AND ALSO TO KEEP UP WITH
FASTER-THAN-FORECAST WARMING THAT IS UNDERWAY. MODELS TYPICALLY
STRUGGLE WITH DEWPOINTS IN THIS SITUATION. DRY AIR FROM ALOFT
SHOULD HAVE NO PROBLEM MIXING DOWN...WITH MODEL SOUNDINGS
SUGGESTING STEEP LAPSE RATES/MIXING ALL THE WAY UP TO 700-600MB
LEVELS. AS ALREADY ACCOUNTED FOR IN FORECAST...GUSTY WINDS SHOULD
HAVE NO PROBLEM MIXING DOWN THROUGHOUT THIS AFTERNOON.
ALSO...VISIBLE SATELLITE SHOWS PLENTY OF CLOUDS CURRENTLY IN
CENTRAL TO NORTHERN ONTARIO AND MOST OF QUEBEC...BEHIND
APPROACHING SECONDARY COLD FRONT. AS DEPICTED BY 800-850MB RH
FIELDS IN RUC AND WRFARW MODELS...A BAND OF CLOUDS AT AROUND 4-5
KFT AGL SHOULD ACCOMPANY SECONDARY FRONT AS IT DROPS DOWN ACROSS
THE NORTHERN HALF OF THE AREA TONIGHT. SKY GRIDS HAVE BEEN UPDATED
ACCORDINGLY. THIS MAY HELP TO STAVE OFF PATCHY FROST THREAT IN
COLD AIR DRAINAGE PRONE VALLEYS OF THE NORTHEASTERN/EASTERN PARTS
OF THE AREA.
PREVIOUS DISCUSSION...
A SECONDARY COLD FRONT WILL DROP SOUTH OUT OF ONTARIO INTO NY LATE
TODAY. VERY DRY ATMOSPHERIC PROFILES WILL PRECLUDE ANY POSSIBILITY
FOR PRECIPITATION.
THE MAIN EFFECT OF THE FRONTAL APPROACH WILL BE TO INCREASE WINDS
DURING THE AFTERNOON HOURS. WITH HEALTHY BL-850MB WINDS PROGGED,
AND A WELL MIXED ATMOSPHERE EXPECTED, IT LOOKS LIKE A GOOD BET
FOR WIND GUSTS OF 20 TO 25 MPH THIS AFTERNOON.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
UL RIDGE BUILDS THROUGH THE OHIO VALLEY AND GREAT LAKES THIS
PERIOD. ATMOSPHERIC MOISTURE WILL REMAIN LOW OVER THE NORTHEASTERN
U.S. THROUGH SATURDAY NIGHT, WITH SLIGHTLY BELOW NORMAL 850MB
TEMPS OVERHEAD.
THE RESULT WILL BE A FAIR WEATHER PERIOD, WITH MILD SUNNY DAYS AND
COOL NIGHTS. CANNOT RULE OUT SOME UPPER 30S MINS TONIGHT AND
POSSIBLY FRIDAY NIGHT, ESPECIALLY IN THE SHELTERED VALLEYS OVER
THE EASTERN FA.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
MODEL AGREEMENT THROUGH THE EXTENDED TIMEFRAME REMAINS LESS THAN
STELLAR THIS AFTERNOON WITH BOTH DETERMINISTIC LONG RANGE MODELS
DISAGREEING ON THE ARRIVAL TIMING OF NEXT WEEK/S UPPER RIDGE. MAIN
PROBLEM REMAINS UPPER BLOCKING SOUTH OF GREENLAND AND REMNANT
UPPER LOW WHICH IS NOW PASSING OFF TO OUR NORTH THIS AFTERNOON.
BOTH MODELS SHOW THIS FEATURE STALLING TO OUR EAST BY THE WEEKEND
ENSURING CYCLONIC NORTHWEST FLOW OVER OUR REGION FOR THE UPCOMING
WEEKEND. THE ECMWF REMAINS THE FASTER SOLUTION IN BRINGING DECENT
RIDGING ALOFT INTO OUR AREAS BY LATE SUN...WHILE THE GFS DELAYS
AND EVEN SUPPRESSES THE APPROACHING RIDGE WITH ITS SUGGESTION THAT
A MIDWEST UPPER LOW WILL DIG SOUTHEAST INTO THE WESTERN GREAT
LAKES. IN ANY EVENT...MAIN FRONTAL BOUNDARY LOOKS TO REMAIN
STALLED SOUTH OF THE FCST REGION THROUGH THE PERIOD WITH A GRADUAL
REDUCTION IN POPS MADE FOR THE UPCOMING WEEKEND. BEYOND
THIS...HAVE GENERALLY FOLLOWED WPC/S GUIDANCE TRENDS WHICH FAVORS A
FAIRLY DECENT WARM UP EARLY NEXT WEEK.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
VFR CONTS THRU THE PD. NW FLOW OF DRY AIR WILL CONT THRU THE PD
KEEPING SKIES CLR OR SCT AT WORST. WINDS WILL INCREASE AND BECOME
GUSTY DIURNALLY WITH MIXING...OTRW LTL CHG THRU THE 24 HR PD.
OUTLOOK...
FRI THROUGH MON...VFR.
&&
.FIRE WEATHER...
GUSTY WEST WINDS ARE FORECAST TODAY, WITH SUNNY SKIES AND LOW
DEW POINTS FORECAST. TEN HOUR FUEL LEVELS WILL NOT MEET RED FLAG
CRITERIA DUE TO FA WIDE GREEN UP. HOWEVER THERE WILL BE ENHANCED
FIRE SENSITIVITY DUE TO THE COMBINATION OF GUSTY WINDS AND DRY
ATMOSPHERE. MINIMUM HUMIDITY LEVELS AREAWIDE SHOULD GET INTO 20S
PERCENT RANGE. PEAK GUSTS OF 20-30 MPH CAN BE EXPECTED IN
NORTHEAST PA...AND 25-35 MPH OR SO IN CENTRAL NY.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJP
NEAR TERM...DJP/MDP
SHORT TERM...DJP
LONG TERM...CMG
AVIATION...DGM
FIRE WEATHER...DJP/MDP
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
742 AM EDT THU MAY 16 2013
.SYNOPSIS...
AN WEST-EAST FRONTAL BOUNDARY ALONG THE MASON DIXON LINE EARLY
THIS MORNING WILL SINK SOUTHWARD INTO THE CENTRAL APPALACHIANS AND
BECOME QUASI-STATIONARY...PIVOTING TO A NW-SE ORIENTATION.
MEANWHILE...HIGH PRESSURE WILL MIGRATE EASTWARD ACROSS
SOUTHEASTERN CANADA WITH ONSHORE FLOW DEVELOPING ACROSS THE MID-
ATLANTIC REGION. THE FRONTAL BOUNDARY WILL SLOWLY PUSH BACK TO THE
NORTH AS A WARM FRONT OVER THE WEEKEND...AND LIFT NORTH OF THE
AREA BY EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
08Z SFC ANALYSIS PLACES QUASI-STATIONARY FRONT FROM SOUTHERN PA
WESTWARD TO SE IOWA. MOST CONVECTIVELY ACTIVE PORTION OF THIS FRONT
IS OVR SE OHIO/SW PA AT 08Z...THE RESULT OF LG SCALE FORCING AHEAD
OF SHORTWAVE MOVING OVR THE E GRT LKS. AS THIS FEATURE TRACKS
EAST...EXPECT THE BEST CHC OF SHRA AND A FEW TSRA TO SHIFT FROM THE
LAUREL HIGHLANDS TO THE LOWER SUSQ VALLEY BY 12Z. LATEST RAP AND
NAMPARA SIMULATED RADAR DATA BOTH INDICATE A SIMILAR SCENARIO
PLAYING OUT EARLY THIS AM.
SHORTWAVE WILL PASS EAST OF THE AREA BY LATE AM...WITH ENOUGH OF A
NWRLY FLOW BEHIND IT TO PUSH THE SFC FRONT JUST SOUTH OF THE MASON
DIXON LINE BY THIS AFTN. DIURNAL HEATING/DESTABILIZATION...COMBINED
WITH APPROACH OF NEXT SHORTWAVE OVR THE GRT LKS...SHOULD CAUSE A NEW
ROUND OF CONVECTION TO FIRE ALONG FRONT JUST SOUTH OF PA THIS AFTN.
WILL MAINTAIN ONLY A SLIGHT CHC ALONG OUR S TIER COUNTIES.
ALTHOUGH TODAY WILL DAWN MCLDY ACROSS SOUTHERN PA...A GOOD DEAL OF
SUNSHINE APPEARS LIKELY EVERYWHERE BY AFTN...AS WNW FLOW DRAWS DRIER
AIR INTO THE STATE. ENS MEAN 8H TEMPS OF ARND 13C SHOULD SUPPORT
HIGH TEMPS FROM THE M70S OVR THE ALLEGHENY PLATEAU...TO THE L80S IN
THE SUSQ VALLEY.
ALL MDL DATA INDICATING HIGH PRES RIDGE AND ASSOC DRY AIR MASS NOSES
SEWRD INTO PA TONIGHT...BRINGING MCLEAR SKIES AND LIGHT WINDS TO ALL
OF CENTRAL PA. THE DRIEST AIR...AS DEPICTED BY GEFS NEGATIVE PWAT
ANOMALIES...REMAIN ACROSS THE NORTHERN HALF OF THE STATE...WHERE
READINGS ARE LIKELY TO DIP INTO THE M/U30S. CAN/T RULE OUT SOME
PATCHY FROST UP THERE...BUT GROWING SEASON HAS NOT OFFICIALLY BEGUN
UP THERE...SO NO ADVISORY NEEDED.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
SFC HIGH PRES WILL SLIDE EWD FROM ONTARIO TO THE MARITIMES BY 12Z
SUNDAY...WITH ONSHORE FLOW DEVELOPING ACRS THE MID-ATLC STATES.
EXPECT SFC RIDGING AND LACK OF ANY SIGNIFICANT MID-UPPER LEVEL
FORCING TO LIMIT PCPN THROUGH MOST OF THE PERIOD. THE HIGHEST POPS
ARE OVER THE SERN ZONES SAT NGT AS AN UPPER LEVEL WAVE DRIFTS EWD
ACRS KY/TN INTO THE CNTRL APPLCHNS AND INTERACTS WITH ONSHORE MSTR
FEED INTERSECTING RETREATING Q-STNRY/WARM FRONT LIFTING NWD OVER
THE MID-ATLC. EXPECT LOW CLOUDS TO DEVELOP FROM SOUTH TO NORTH ON
SAT NGT IN SELY FLOW REGIME. TEMPS WILL BE WARMER ON FRIDAY WITH
MORE SUN.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
GUIDANCE CONTINUES TO TREND COOLER FOR SUNDAY WITH HIGHS IN THE
MID-UPPER 60S...AS MOIST ONSHORE FLOW STRENGTHENS /-2SD 850MB U
WIND ANOMALY IN GEFS/ AND BRINGS EXTENSIVE CLOUD COVER TO THE
REGION. MDL LI PROGS SHOW A CAD PATTERN IN THE LOW-LEVELS AS THE
WARM FRONT PIVOTS AND STALLS ALONG THE ALLEGHENY FRONT. WITH
STABLE CONDITIONS EXPECTED...CHANGED WX TYPE TO LGT RAIN AS
INSTABILITY SHOULD BE LOCATED WEST OF THE MTNS. FOCUS FOR PCPN
INTO MONDAY SHOULD REMAIN SOUTH OF PA OVER THE VA/NC IN CONJCT
WITH UPPER LEVEL WAVE AND MAX PWAT ANOM NR +2SD. HIGHEST POPS ARE
AGAIN OVER THE ERN 1/2 OF THE CWA AS SELY FLOW CONTS TO IMPINGE ON
SLOWLY RETREATING/DIFFUSE N-S WARM FRONT.
THE LG SCALE PATTERN IS FCST TO TURN DECIDEDLY MORE AMPLIFIED NEXT
WEEK...WITH THE MAIN SYNOPTIC FEATURE OF INTEREST BEING AN UPPER
LOW OVER THE NRN PLAINS/UPR MS VLY. H5 HGTS SHOULD RISE DOWNSTREAM
OF THIS SYSTEM...WITH CENTRAL PA LKLY BREAKING INTO THE WARM
SECTOR BY NEXT TUES AS THE PESKY WARM FRONT LIFTS NORTH INTO NEW
ENGLAND. THIS SHOULD AFFORD ONE OR TWO VERY WARM LATE SPRING DAYS
WITH HIGHS 75-80F. THERE IS A HIGH SPREAD BETWEEN THE GFS/ECMWF
CONCERNING THE POTENTIAL UPPER MIDWEST CUT-OFF. THEREFORE UTILIZED
A 50/50 BLEND OF THEIR RESPECTIVE MOS PRODUCTS FOR THE DAY 5-7
FCST.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
A SLOW-MOVING COLD FRONT WILL BE ACCOMPANIED BY A ROUND OF SHRA
AND PERHAPS EVEN AN ISOLATED TSRA EARLY THIS MORNING ACROSS THE
SOUTHERN PA AIRFIELDS. 11Z RADAR LOOP SUGGESTS AOO/JST/MDT WILL
LIKELY IMPROVE TO VFR BTWN 12Z-13Z....WHILE SHRA/REDUCED VSBYS
MAY LINGER AT LNS UNTIL 13Z-14Z.
BY LATE MORNING...THE FRONTAL BOUNDARY SHOULD SHIFT SOUTH OF
PA...RESULTING IN A HIGH DEGREE OF CONFIDENCE IN VFR CONDS ACROSS
THE ENTIRE STATE.
.OUTLOOK...
FRI-SUN...NO SIG WX EXPECTED.
MON...AM LOW CIGS POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...FITZGERALD
SHORT TERM...STEINBUGL
LONG TERM...STEINBUGL
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1138 AM MDT THU MAY 16 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 358 AM MDT THU MAY 16 2013
A LINE OF RADAR ECHOES WAS MOVING THRU THE FAR ERN COUNTIES THIS
MORNING...BUT ARE EXPECTED TO BE OUT OF THE AREA BY 6 AM. A
SHORTWAVE TROF WL CONTINUE MOVING EASTWARD ACRS CO TODAY WITH THE
AXIS EXPECTED TO BE NR THE ERN BORDER BY EVENING. BEHIND THE UPR
DISTURBANCE DRIER AIR WL SPREAD FROM WEST TO EAST...BUT THERE SHOULD
STILL BE ENOUGH MSTR AROUND FOR ISOLD TO SCT SHOWERS AND TSTMS OVR
AND NR THE HYR TRRN. SOME LOW LEVEL CONVERGENCE...BETTER LOW LEVEL
MSTR AND CAPE VALUES APPROACHING 600 J/KG...ALONG WITH THE UPR SHRTWV
TROF ARE ALSO EXPECTED TO ENHANCE CHANCES FOR SHOWERS AND TSTMS OVR
THE FAR ERN COUNTIES THIS AFTERNOON. HIGH TEMPS TODAY ACRS THE AREA
WL BE ABOVE NORMAL FOR THIS TIME OF YEAR. THE UPR LEVEL DISTURBANCE
WL EXIT THE STATE THIS EVENING AND PCPN IS EXPECTED TO END BY
MIDNIGHT. THE NAM CONTINUES TO SHOW A LOT OF LOW LEVEL MSTR OVR THE
FAR EASTERN AREAS LATE TONIGHT AND WL PROBABLY RESULT IN SOME
STRATUS AND POSSIBLY FOG.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 358 AM MDT THU MAY 16 2013
FRIDAY-FRIDAY NIGHT...SOUTHWEST FLOW ALOFT PROGGED TO SLOWLY
INCREASE FROM WEST TO EAST ACROSS THE AREA AS NEXT UPPER TROUGH
DIGS ACROSS THE WEST COAST AND INTO THE GREAT BASIN FRIDAY NIGHT.
MODELS INDICATING DRY AND WARM CONDITIONS ACROSS THE AREA FRIDAY
WITH POSSIBLE CRITICAL FIRE WEATHER CONDITIONS DEVELOPING ACROSS
WESTERN PORTIONS OF THE DISTRICT FRIDAY AFTERNOON WITH INCREASING
MID LEVEL FLOW AND EXPECTED DEEP MIXING. MAY NEED SOME FIRE WEATHER
HIGHLIGHTS ESPECIALLY FOR THE SW MTS AND SAN LUIS VALLEY...THOUGH
WILL NEED TO SEE HOW FUELS ARE AT THIS TIME. WARM AIR ALOFT (10-14C
AT H7) ALONG WITH THE DOWNSLOPE FLOW WILL SUPPORT HIGH TEMPERATURES
IN THE 80S TO LOWER 90S ACROSS THE PLAINS AND MAINLY 60S AND 70S
ACROSS THE HIGHER TERRAIN AND MT VALLEYS.
SATURDAY-MONDAY...LATEST MODELS CONTINUE TO INDICATE MORE UNSETTLED
WEATHER THROUGH EARLY NEXT WEEK AS GREAT BASIN UPPER TROUGH LIFTS
OUT ACROSS THE CENTRAL ROCKIES THROUGH SATURDAY NIGHT WITH SECONDARY
ENERGY PROGGED TO DIG ACROSS THE NORTHERN GREAT BASIN AND THE
NORTHERN ROCKIES SUNDAY AND SUNDAY NIGHT. INCREASING MID AND UPPER
LEVEL MOISTURE AND UVV ACROSS THE AREA SATURDAY SUPPORTS ISOLATED TO
SCATTERED HIGH BASED CONVECTION ACROSS THE AREA SATURDAY AFTERNOON
AND EVENING...WITH BEST CHANCES OF SEEING WETTING RAINS ACROSS THE
CENTRAL AND SOUTHWEST MTS. ASSOCIATED LEE TROUGHING MOVES ACROSS THE
PLAINS THROUGH THE AFTERNOON...THOUGH LOOKS LIKE BEST LOW LEVEL
MOISTURE REMAINS WELL INTO WESTERN KANSAS. COOLING ALOFT SUPPORTS
HIGHS ON SATURDAY SOME 4-9F COOLER THAN FRIDAY...WITH POSSIBLE
CRITICAL FIRE WEATHER CONDITIONS SHIFTING OUT ACROSS THE FAR SE
PLAINS. TEMPS ALOFT COOL MORE ON SUNDAY WITH COOL AND BRISK
NORTHWEST FLOW ALOFT ACROSS THE AREA ON MONDAY AS SECONDARY ENERGY
DIGS ACROSS THE ROCKIES AND INTO THE HIGH PLAINS. ISOLATED TO
SCATTERED AFTERNOON AND EVENING POPS ACROSS THE AREA AGAIN SUNDAY
WITH PASSING SECONDARY ENERGY WITH THE GFS SUGGESTING A DRIER AND
SUBSIDENT AIRMASS ACROSS THE AREA ON MONDAY. THE LATEST
ECMWF...HOWEVER...IS A TAD SLOWER AND FURTHER SOUTH WITH THE
SECONDARY ENERGY DIGGING ACROSS THE CENTRAL ROCKIES MONDAY
AFTERNOON...WHICH WOULD KEEP THE UNSETTLED WEATHER IN PLACE ON
MONDAY. WITH THE COOLING ALOFT...SUNDAY AND MONDAY LOOK TO BE THE
COOLEST DAYS OF THE UPCOMING WEEK.
TUESDAY-THURSDAY...WARMER AND DRIER WEATHER EXPECTED AS UPPER LEVEL
RIDGING BUILDS ACROSS THE ROCKIES AHEAD OF ANOTHER TROUGH DIGGING
ACROSS THE WEST COAST WEDNESDAY. WARMING ALOFT WILL ALLOW TEMPS TO
WARM BACK TO AT AND SLIGHTLY ABOVE SEASONAL AVERAGES THROUGH MID
WEEK. ISOLATED HIGH BASED STORMS REMAIN POSSIBLE OVER THE HIGHER
TERRAIN THROUGH MID WEEK WITH INCREASING SOUTHERLY FLOW ALOFT
THURSDAY ALLOWING FOR INCREASING LOW LEVEL MOISTURE ACROSS THE AREA
ON THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1058 AM MDT THU MAY 16 2013
VFR CONDITIONS ARE EXPECTED DURING THE NEXT 24H AT ALL 3 TAF
SITES...KPUB...KALS AND KCOS. SFC WINDS WILL BE DIURNALLY DRIVEN.
THERE IS A LOW PROBABILITY OF A PASSING SHOWER/TSRA AT KCOS LATER
THIS AFTERNOON AND EARLY EVENING...BUT PROBABILITY TOO LOW TO
MENTION EXPLICITLY IN TAF AS BOTH HRRR MODEL AND LOCAL WRF ARE
COMING IN DRY.
&&
.FIRE WEATHER...
ISSUED AT 1134 AM MDT THU MAY 16 2013
BASED ON LATEST DATA FROM FOREST SERVICE AND MODEL
GUIDANCE...WILL ISSUE A RED FLAG WARNING FOR THE SOUTHWEST
MTNS...SAN LUIS VALLEY AND THE SOUTHERN MTNS FOR TOMORROW. OTHER
AREAS WILL SEE RED FLAG CRITERIA TOMORROW...BUT THE FUELS WILL NOT
CARRY FIRE ACCORDING THE THE FOREST SERVICE FUELS PAGE.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM NOON TO 8 PM MDT FRIDAY FOR COZ222>225.
&&
$$
SHORT TERM...28
LONG TERM...MW
AVIATION...HODANISH
FIRE WEATHER...HODANISH
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1128 AM MDT THU MAY 16 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 358 AM MDT THU MAY 16 2013
A LINE OF RADAR ECHOES WAS MOVING THRU THE FAR ERN COUNTIES THIS
MORNING...BUT ARE EXPECTED TO BE OUT OF THE AREA BY 6 AM. A
SHORTWAVE TROF WL CONTINUE MOVING EASTWARD ACRS CO TODAY WITH THE
AXIS EXPECTED TO BE NR THE ERN BORDER BY EVENING. BEHIND THE UPR
DISTURBANCE DRIER AIR WL SPREAD FROM WEST TO EAST...BUT THERE SHOULD
STILL BE ENOUGH MSTR AROUND FOR ISOLD TO SCT SHOWERS AND TSTMS OVR
AND NR THE HYR TRRN. SOME LOW LEVEL CONVERGENCE...BETTER LOW LEVEL
MSTR AND CAPE VALUES APPROACHING 600 J/KG...ALONG WITH THE UPR SHRTWV
TROF ARE ALSO EXPECTED TO ENHANCE CHANCES FOR SHOWERS AND TSTMS OVR
THE FAR ERN COUNTIES THIS AFTERNOON. HIGH TEMPS TODAY ACRS THE AREA
WL BE ABOVE NORMAL FOR THIS TIME OF YEAR. THE UPR LEVEL DISTURBANCE
WL EXIT THE STATE THIS EVENING AND PCPN IS EXPECTED TO END BY
MIDNIGHT. THE NAM CONTINUES TO SHOW A LOT OF LOW LEVEL MSTR OVR THE
FAR EASTERN AREAS LATE TONIGHT AND WL PROBABLY RESULT IN SOME
STRATUS AND POSSIBLY FOG.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 358 AM MDT THU MAY 16 2013
FRIDAY-FRIDAY NIGHT...SOUTHWEST FLOW ALOFT PROGGED TO SLOWLY
INCREASE FROM WEST TO EAST ACROSS THE AREA AS NEXT UPPER TROUGH
DIGS ACROSS THE WEST COAST AND INTO THE GREAT BASIN FRIDAY NIGHT.
MODELS INDICATING DRY AND WARM CONDITIONS ACROSS THE AREA FRIDAY
WITH POSSIBLE CRITICAL FIRE WEATHER CONDITIONS DEVELOPING ACROSS
WESTERN PORTIONS OF THE DISTRICT FRIDAY AFTERNOON WITH INCREASING
MID LEVEL FLOW AND EXPECTED DEEP MIXING. MAY NEED SOME FIRE WEATHER
HIGHLIGHTS ESPECIALLY FOR THE SW MTS AND SAN LUIS VALLEY...THOUGH
WILL NEED TO SEE HOW FUELS ARE AT THIS TIME. WARM AIR ALOFT (10-14C
AT H7) ALONG WITH THE DOWNSLOPE FLOW WILL SUPPORT HIGH TEMPERATURES
IN THE 80S TO LOWER 90S ACROSS THE PLAINS AND MAINLY 60S AND 70S
ACROSS THE HIGHER TERRAIN AND MT VALLEYS.
SATURDAY-MONDAY...LATEST MODELS CONTINUE TO INDICATE MORE UNSETTLED
WEATHER THROUGH EARLY NEXT WEEK AS GREAT BASIN UPPER TROUGH LIFTS
OUT ACROSS THE CENTRAL ROCKIES THROUGH SATURDAY NIGHT WITH SECONDARY
ENERGY PROGGED TO DIG ACROSS THE NORTHERN GREAT BASIN AND THE
NORTHERN ROCKIES SUNDAY AND SUNDAY NIGHT. INCREASING MID AND UPPER
LEVEL MOISTURE AND UVV ACROSS THE AREA SATURDAY SUPPORTS ISOLATED TO
SCATTERED HIGH BASED CONVECTION ACROSS THE AREA SATURDAY AFTERNOON
AND EVENING...WITH BEST CHANCES OF SEEING WETTING RAINS ACROSS THE
CENTRAL AND SOUTHWEST MTS. ASSOCIATED LEE TROUGHING MOVES ACROSS THE
PLAINS THROUGH THE AFTERNOON...THOUGH LOOKS LIKE BEST LOW LEVEL
MOISTURE REMAINS WELL INTO WESTERN KANSAS. COOLING ALOFT SUPPORTS
HIGHS ON SATURDAY SOME 4-9F COOLER THAN FRIDAY...WITH POSSIBLE
CRITICAL FIRE WEATHER CONDITIONS SHIFTING OUT ACROSS THE FAR SE
PLAINS. TEMPS ALOFT COOL MORE ON SUNDAY WITH COOL AND BRISK
NORTHWEST FLOW ALOFT ACROSS THE AREA ON MONDAY AS SECONDARY ENERGY
DIGS ACROSS THE ROCKIES AND INTO THE HIGH PLAINS. ISOLATED TO
SCATTERED AFTERNOON AND EVENING POPS ACROSS THE AREA AGAIN SUNDAY
WITH PASSING SECONDARY ENERGY WITH THE GFS SUGGESTING A DRIER AND
SUBSIDENT AIRMASS ACROSS THE AREA ON MONDAY. THE LATEST
ECMWF...HOWEVER...IS A TAD SLOWER AND FURTHER SOUTH WITH THE
SECONDARY ENERGY DIGGING ACROSS THE CENTRAL ROCKIES MONDAY
AFTERNOON...WHICH WOULD KEEP THE UNSETTLED WEATHER IN PLACE ON
MONDAY. WITH THE COOLING ALOFT...SUNDAY AND MONDAY LOOK TO BE THE
COOLEST DAYS OF THE UPCOMING WEEK.
TUESDAY-THURSDAY...WARMER AND DRIER WEATHER EXPECTED AS UPPER LEVEL
RIDGING BUILDS ACROSS THE ROCKIES AHEAD OF ANOTHER TROUGH DIGGING
ACROSS THE WEST COAST WEDNESDAY. WARMING ALOFT WILL ALLOW TEMPS TO
WARM BACK TO AT AND SLIGHTLY ABOVE SEASONAL AVERAGES THROUGH MID
WEEK. ISOLATED HIGH BASED STORMS REMAIN POSSIBLE OVER THE HIGHER
TERRAIN THROUGH MID WEEK WITH INCREASING SOUTHERLY FLOW ALOFT
THURSDAY ALLOWING FOR INCREASING LOW LEVEL MOISTURE ACROSS THE AREA
ON THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1058 AM MDT THU MAY 16 2013
VFR CONDITIONS ARE EXPECTED DURING THE NEXT 24H AT ALL 3 TAF
SITES...KPUB...KALS AND KCOS. SFC WINDS WILL BE DIURNALLY DRIVEN.
THERE IS A LOW PROBABILITY OF A PASSING SHOWER/TSRA AT KCOS LATER
THIS AFTERNOON AND EARLY EVENING...BUT PROBABILITY TOO LOW TO
MENTION EXPLICITLY IN TAF AS BOTH HRRR MODEL AND LOCAL WRF ARE
COMING IN DRY.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...28
LONG TERM...MW
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
506 PM EDT THU MAY 16 2013
.SYNOPSIS...
A COLD FRONT WILL PUSH TO OUR SOUTH TONIGHT AND STALL TO OUR SOUTH
THROUGH THE UPCOMING WEEKEND. THE FRONTAL BOUNDARY IS EXPECTED TO
RETURN NORTHWARD AS A WARM FRONT LATE MONDAY INTO TUESDAY. ANOTHER
FRONTAL SYSTEM IS EXPECTED TO APPROACH THE AREA FROM THE WEST AND
MOVE THROUGH THE AREA DURING THE MIDDLE TO LATE PART OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
WE LOWERED AREAL COVERAGE TO ISOLATED AS LATEST LAPS SOUNDINGS ALL
HAVE CAPES LESS THAN 1K JOULES. IF THERE IS A WINDOW FOR A TSRA TO
POP, IT IS FAIRLY SMALL AND ITS CLOSING FAST.
DURING THE AFTERNOON, INSTABILITY AND MOISTURE WERE TRYING TO MOVE
IN FROM THE SOUTHWEST ACROSS THE AREA NEAR AND SOUTH OF THE I-78
CORRIDOR TO TAP SOME LINGERING MID LEVEL FORCING. AS ONE MOVED
FURTHER EAST ACROSS THAT AREA, THERE STILL WAS A CONSIDERABLE AMOUNT
OF CIN TO OVERCOME AS OF 18Z. OUR TAKE ON THIS IS THAT THE BEST
CHANCES FOR ACTIVITY EARLY IN THE NEAR TERM ARE OVER THE
SOUTHWESTERN PART OF THE FORECAST AREA, ALTHOUGH THE LATEST HRRR RUN
BROUGHT SOME SCATTERED ACTIVITY FURTHER NORTH. SINCE IT WAS FAIRLY
ACCURATE WITH THE MORNING ACTIVITY, WE KEPT A SLIGHT CHANCE WHERE
THE RAPID REFRESH INDICATED, BUT WE HAVE THE BEST CHANCE SOUTH OF
THE MASON-DIXON LINE. WE EXPECT TO LOSE ANY CONVECTION BY MIDNIGHT
AS A SECONDARY COLD FRONT WILL DROP ACROSS THE AREA AND PUSH DRIER
AIR SOUTH.
TEMPERATURES ARE A GUIDANCE/CONTINUITY BLEND. UP NORTH, THERE MAY BE
SOME RADIATING WITH LOWER DEW POINTS ALREADY IN PLACE AND WINDS
EXPECTED TO GO LIGHT AT LEAST INTO THE EVENING HOURS. THE SECONDARY
FRONT MAY MIX THINGS A BIT AND TURN THE REST OF THE NIGHT INTO A
MILDLY ADVECTIVE ONE.
&&
.SHORT TERM /6 AM FRIDAY THROUGH 6 AM FRIDAY/...
OUR FORECAST IS THAT THE SURFACE HIGH RIDGING DOWN FROM CENTRAL
CANADA AND SOME LOCAL MID LEVEL RIDGING TO OUR WEST (AHEAD OF A SLOW
MOVING SYSTEM THAT WAS THE CLOSED LOW RESPONSIBLE FOR THE SPLIT FLOW
EARLIER IN THE WEEK) WILL CARVE OUT A DRY DAY FOR THE ENTIRE
FORECAST AREA. THERE SHOULD BE A DECENT AMOUNT OF SUNSHINE, ALTHOUGH
SOME HIGH CLOUDINESS MAY BEGIN TO INVADE FROM THE SOUTH AND WEST
DURING THE COURSE OF THE DAY. WINDS SHOULD BE RATHER LIGHT AS HIGH
PRESSURE MOVES OVER US. TEMPERATURES ARE A GUIDANCE/CONTINUITY BLEND
IN LINE WITH H925 TEMPERATURES, AND ARE FORECAST TO BE A BIT ABOVE
NORMAL. THE CAVEAT IS THAT WE EXPECT A SEA BREEZE TO DEVELOP DURING
THE COURSE OF THE DAY.
&&
.LONG TERM /FRIDAY THROUGH THURSDAY/...
THE COLD FRONT WILL REMAIN STALLED TO OUR SOUTH FOR THE UPCOMING
WEEKEND. FRIDAY NIGHT INTO SATURDAY, HIGH PRESSURE WILL NOSE DOWN
ACROSS OUR AREA FROM THE NORTH, KEEPING THE FRONT TO OUR SOUTH AND
KEEPING OUR AREA IN MORE OF AN EASTERLY/SOUTHEASTERLY FLOW. SOME
GUIDANCE IS TRYING TO BRING SOME LIGHT QPF ACROSS THE AREA AS EARLY
AS FRIDAY NIGHT, BUT WE WILL KEEP FRIDAY NIGHT DRY. AS WE MOVE INTO
THE WEEKEND, A SLOW MOVING SHORT WAVE WILL BE SLIDING ACROSS THE
OHIO RIVER VALLEY AND TOWARD THE EAST COAST. THIS WILL PUSH SEVERAL
WEAK DISTURBANCES ACROSS THE AREA THROUGH THE WEEKEND, WHICH MAY
HELP CREATE SOME SHOWER ACTIVITY. THE AIRMASS SHOULD BE FAIRLY
STABLE, SO WE ARE NOT EXPECTING THUNDERSTORMS AT THIS TIME. WITH THE
EASTERLY/SOUTHEASTERLY FLOW, TEMPERATURES ARE NOT EXPECTED TO WARM
SIGNIFICANTLY EITHER.
AS THE HIGH PRESSURE REMAINS TO OUR NORTHEAST AND SLOWLY BUILDS OUT
TO SEA MONDAY INTO TUESDAY, MOISTURE WILL CONTINUE TO PUSH ACROSS
THE AREA THROUGH EARLY NEXT WEEK. THE FRONTAL BOUNDARY TO OUR SOUTH
IS EXPECTED TO BEGIN PUSHING BACK NORTHWARD AS A WARM FRONT AS WELL,
AND MAY MOVE THROUGH THE AREA BY MONDAY NIGHT INTO TUESDAY. WE COULD
CONTINUE TO SEE SOME PRECIPITATION ACROSS THE AREA AHEAD OF THE WARM
FRONTAL BOUNDARY AS SEVERAL WEAK DISTURBANCES MOVE ACROSS THE AREA
IN THE WESTERLY FLOW ALOFT.
AFTER THE WARM FRONT MOVES THROUGH, TUESDAY AND WEDNESDAY OF NEXT
WEEK LOOK TO BE THE WARMEST DAYS. WE DID NOT GO AS HIGH AS WHAT THE
850 MB ECMWF/GFS TEMPS WOULD FORECAST FOR SURFACE MAXES, BUT WE
SHOULD BE ABLE TO REACH AT LEAST THE LOW 80S FOR MUCH OF THE AREA.
WE WILL KEEP A CHANCE OF SHOWERS/THUNDERSTORMS IN THE FORECAST
TUESDAY/WEDNESDAY AS WE SHOULD BE IN THE WARM SECTOR AHEAD OF THE
NEXT APPROACHING FRONTAL SYSTEM. ANY SHORT WAVES/VORT MAXES COULD
HELP CREATE SHOWERS/THUNDERSTORMS WITH THE AVAILABLE INSTABILITY.
THE LATEST GFS/ECMWF VARY ON THEIR TIMING OF THE NEXT FRONTAL
SYSTEM. THE GFS BRINGS THE FRONT THROUGH WEDNESDAY NIGHT INTO
THURSDAY, WHILE THE ECMWF BRINGS IT THROUGH THURSDAY NIGHT INTO
FRIDAY. BEING SO FAR OUT, WE WILL KEEP A CHANCE OF SHOWERS IN THE
FORECAST THROUGH THURSDAY NIGHT FOR NOW.
&&
.AVIATION /21Z THURSDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
SHOWER ACTIVITY HAD SLIPPED INTO THE MARYLAND EASTERN SHORE,
CENTRAL AND SOUTHERN DELAWARE AND FAR SOUTHERN NJ EARLY THIS
AFTERNOON. RADAR TRENDS SUGGESTED THAT ONLY SOME LIGHT SHOWERS
THREATENED THE SOUTHEASTERN TAF SITES EARLY. FURTHER NORTH, THERE IS
ONLY A SLIGHT CHANCE OF ANY ACTIVITY. ALL THE TAFS ARE VFR WITH SOME
CUMULUS EARLY AND THEN MID AND HIGH CLOUDS RECEDING SOUTHWARD TONIGHT.
MAINLY HIGH CLOUDS WITH PERHAPS A FEW CUMULUS ARE EXPECTED ON
FRIDAY. DRIER AIR IS EXPECTED TO MOVE DOWN FROM THE NORTH TONIGHT,
SO WE DON`T FORECAST ANY OVERNIGHT VISIBILITY RESTRICTIONS.
REGARDING WINDS, THE LATEST MODELS SHOW THEM PICKING UP FROM OUT OF
THE WEST EARLY IN THE TAF PERIOD WITH SOME GUSTS ABOVE 20 KT
POSSIBLE, THEN THEY SHOULD RELAX THIS EVENING BEFORE SHIFTING TO THE
NORTH OVERNIGHT THANKS TO A SECONDARY COLD FRONT. GENERALLY, WINDS
SHOULD BE RATHER GENTLE ON FRIDAY.
A SEA BREEZE HAD DEVELOPED AT ACY EARLIER TODAY, BUT WE THINK THE
STRENGTHENING WEST WIND WILL OVERWHELM IT EARLY IN THE TAF PERIOD. A
SEA BREEZE LIKELY WILL AFFECT ACY ON FRIDAY.
OUTLOOK...
FRIDAY NIGHT...MOSTLY VFR.
SATURDAY-SATURDAY NIGHT...MAINLY VFR WITH LOWERING CLOUDS. A
SLIGHT CHANCE OF SHOWERS AND SOUTH TO SOUTHEAST WINDS AROUND 5
KNOTS.
SUNDAY-SUNDAY NIGHT...GENERALLY VFR EXPECTED, POSSIBLE MVFR CIGS,
ESPECIALLY WITH ANY SHOWERS.
MONDAY-TUESDAY...GENERALLY VFR, POSSIBLE MVFR CIGS/VSBYS,
ESPECIALLY WITH ANY SHOWERS/THUNDERSTORMS.
&&
.MARINE...
WE WILL LET THE SCA FOR HAZARDOUS SEAS EXPIRE AS SEAS ARE TRENDING
DOWNWARD AT BUOY 65. WINDS AND SEAS OVER ALL WATERS ARE NOW BELOW
ADVISORY CRITERIA THROUGH FRIDAY.
LIGHT WINDS THROUGH THIS EVENING ARE EXPECTED TO BECOME NORTHERLY
AND PICK UP SOME AS A SECONDARY COLD FRONT DROPS ACROSS THE COASTAL
WATERS OF NEW JERSEY AND DELAWARE. FORECAST PRESSURE RISES SUPPORT A
MODERATE BUT NOT ADVISORY LEVEL WIND. WINDS SHOULD DIMINISH AGAIN ON
FRIDAY. THE WINDS MAY BECOME ONSHORE NEAR LAND.
OUTLOOK...
CONDITIONS SHOULD REMAIN BELOW ADVISORY LEVELS THROUGH SATURDAY.
HOWEVER, WINDS MAY RETURN CLOSE TO ADVISORY LEVELS STARTING
SATURDAY NIGHT INTO SUNDAY AS THE PRESSURE GRADIENT TIGHTENS
ACROSS THE WATERS AS HIGH PRESSURE PUSHES OFF THE NORTHEAST COAST.
WITH THE EASTERLY/SOUTHEASTERLY FLOW, SEAS MAY RETURN TO SMALL
CRAFT ADVISORY LEVELS DUE TO THE LONG FETCH STARTING SUNDAY AND
CONTINUING INTO TUESDAY.
&&
.FIRE WEATHER...
WE WILL MENTION IN THE FIRE WEATHER FORECAST THAN MINIMUM RELATIVE
HUMIDITY LEVELS WILL DROP TO OR BELOW 30 PERCENT ON FRIDAY AFTERNOON
FOR MUCH OF THE FORECAST AREA. WINDS AND FINE FUELS ARE NOT A
CONCERN.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ROBERTSON
NEAR TERM...DELISI
SHORT TERM...DELISI
LONG TERM...ROBERTSON
AVIATION...DELISI/ROBERTSON
MARINE...DELISI/GIGI/ROBERTSON
FIRE WEATHER...DELISI
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
356 PM EDT THU MAY 16 2013
.SYNOPSIS...
A COLD FRONT WILL PUSH TO OUR SOUTH TONIGHT AND STALL TO OUR SOUTH
THROUGH THE UPCOMING WEEKEND. THE FRONTAL BOUNDARY IS EXPECTED TO
RETURN NORTHWARD AS A WARM FRONT LATE MONDAY INTO TUESDAY. ANOTHER
FRONTAL SYSTEM IS EXPECTED TO APPROACH THE AREA FROM THE WEST AND
MOVE THROUGH THE AREA DURING THE MIDDLE TO LATE PART OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
DURING THE AFTERNOON, INSTABILITY AND MOISTURE WERE TRYING TO MOVE
IN FROM THE SOUTHWEST ACROSS THE AREA NEAR AND SOUTH OF THE I-78
CORRIDOR TO TAP SOME LINGERING MID LEVEL FORCING. AS ONE MOVED
FURTHER EAST ACROSS THAT AREA, THERE STILL WAS A CONSIDERABLE AMOUNT
OF CIN TO OVERCOME AS OF 18Z. OUR TAKE ON THIS IS THAT THE BEST
CHANCES FOR ACTIVITY EARLY IN THE NEAR TERM ARE OVER THE
SOUTHWESTERN PART OF THE FORECAST AREA, ALTHOUGH THE LATEST HRRR RUN
BROUGHT SOME SCATTERED ACTIVITY FURTHER NORTH. SINCE IT WAS FAIRLY
ACCURATE WITH THE MORNING ACTIVITY, WE KEPT A SLIGHT CHANCE WHERE
THE RAPID REFRESH INDICATED, BUT WE HAVE THE BEST CHANCE SOUTH OF
THE MASON-DIXON LINE. WE EXPECT TO LOSE ANY CONVECTION BY MIDNIGHT
AS A SECONDARY COLD FRONT WILL DROP ACROSS THE AREA AND PUSH DRIER
AIR SOUTH.
TEMPERATURES ARE A GUIDANCE/CONTINUITY BLEND. UP NORTH, THERE MAY BE
SOME RADIATING WITH LOWER DEW POINTS ALREADY IN PLACE AND WINDS
EXPECTED TO GO LIGHT AT LEAST INTO THE EVENING HOURS. THE SECONDARY
FRONT MAY MIX THINGS A BIT AND TURN THE REST OF THE NIGHT INTO A
MILDLY ADVECTIVE ONE.
&&
.SHORT TERM /6 AM FRIDAY THROUGH 6 AM FRIDAY/...
OUR FORECAST IS THAT THE SURFACE HIGH RIDGING DOWN FROM CENTRAL
CANADA AND SOME LOCAL MID LEVEL RIDGING TO OUR WEST (AHEAD OF A SLOW
MOVING SYSTEM THAT WAS THE CLOSED LOW RESPONSIBLE FOR THE SPLIT FLOW
EARLIER IN THE WEEK) WILL CARVE OUT A DRY DAY FOR THE ENTIRE
FORECAST AREA. THERE SHOULD BE A DECENT AMOUNT OF SUNSHINE, ALTHOUGH
SOME HIGH CLOUDINESS MAY BEGIN TO INVADE FROM THE SOUTH AND WEST
DURING THE COURSE OF THE DAY. WINDS SHOULD BE RATHER LIGHT AS HIGH
PRESSURE MOVES OVER US. TEMPERATURES ARE A GUIDANCE/CONTINUITY BLEND
IN LINE WITH H925 TEMPERATURES, AND ARE FORECAST TO BE A BIT ABOVE
NORMAL. THE CAVEAT IS THAT WE EXPECT A SEA BREEZE TO DEVELOP DURING
THE COURSE OF THE DAY.
&&
.LONG TERM /FRIDAY THROUGH THURSDAY/...
THE COLD FRONT WILL REMAIN STALLED TO OUR SOUTH FOR THE UPCOMING
WEEKEND. FRIDAY NIGHT INTO SATURDAY, HIGH PRESSURE WILL NOSE DOWN
ACROSS OUR AREA FROM THE NORTH, KEEPING THE FRONT TO OUR SOUTH AND
KEEPING OUR AREA IN MORE OF AN EASTERLY/SOUTHEASTERLY FLOW. SOME
GUIDANCE IS TRYING TO BRING SOME LIGHT QPF ACROSS THE AREA AS EARLY
AS FRIDAY NIGHT, BUT WE WILL KEEP FRIDAY NIGHT DRY. AS WE MOVE INTO
THE WEEKEND, A SLOW MOVING SHORT WAVE WILL BE SLIDING ACROSS THE
OHIO RIVER VALLEY AND TOWARD THE EAST COAST. THIS WILL PUSH SEVERAL
WEAK DISTURBANCES ACROSS THE AREA THROUGH THE WEEKEND, WHICH MAY
HELP CREATE SOME SHOWER ACTIVITY. THE AIRMASS SHOULD BE FAIRLY
STABLE, SO WE ARE NOT EXPECTING THUNDERSTORMS AT THIS TIME. WITH THE
EASTERLY/SOUTHEASTERLY FLOW, TEMPERATURES ARE NOT EXPECTED TO WARM
SIGNIFICANTLY EITHER.
AS THE HIGH PRESSURE REMAINS TO OUR NORTHEAST AND SLOWLY BUILDS OUT
TO SEA MONDAY INTO TUESDAY, MOISTURE WILL CONTINUE TO PUSH ACROSS
THE AREA THROUGH EARLY NEXT WEEK. THE FRONTAL BOUNDARY TO OUR SOUTH
IS EXPECTED TO BEGIN PUSHING BACK NORTHWARD AS A WARM FRONT AS WELL,
AND MAY MOVE THROUGH THE AREA BY MONDAY NIGHT INTO TUESDAY. WE COULD
CONTINUE TO SEE SOME PRECIPITATION ACROSS THE AREA AHEAD OF THE WARM
FRONTAL BOUNDARY AS SEVERAL WEAK DISTURBANCES MOVE ACROSS THE AREA
IN THE WESTERLY FLOW ALOFT.
AFTER THE WARM FRONT MOVES THROUGH, TUESDAY AND WEDNESDAY OF NEXT
WEEK LOOK TO BE THE WARMEST DAYS. WE DID NOT GO AS HIGH AS WHAT THE
850 MB ECMWF/GFS TEMPS WOULD FORECAST FOR SURFACE MAXES, BUT WE
SHOULD BE ABLE TO REACH AT LEAST THE LOW 80S FOR MUCH OF THE AREA.
WE WILL KEEP A CHANCE OF SHOWERS/THUNDERSTORMS IN THE FORECAST
TUESDAY/WEDNESDAY AS WE SHOULD BE IN THE WARM SECTOR AHEAD OF THE
NEXT APPROACHING FRONTAL SYSTEM. ANY SHORT WAVES/VORT MAXES COULD
HELP CREATE SHOWERS/THUNDERSTORMS WITH THE AVAILABLE INSTABILITY.
THE LATEST GFS/ECMWF VARY ON THEIR TIMING OF THE NEXT FRONTAL
SYSTEM. THE GFS BRINGS THE FRONT THROUGH WEDNESDAY NIGHT INTO
THURSDAY, WHILE THE ECMWF BRINGS IT THROUGH THURSDAY NIGHT INTO
FRIDAY. BEING SO FAR OUT, WE WILL KEEP A CHANCE OF SHOWERS IN THE
FORECAST THROUGH THURSDAY NIGHT FOR NOW.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
SHOWER ACTIVITY HAD SLIPPED INTO THE MARYLAND EASTERN SHORE,
CENTRAL AND SOUTHERN DELAWARE AND FAR SOUTHERN NJ EARLY THIS
AFTERNOON. RADAR TRENDS SUGGESTED THAT ONLY SOME LIGHT SHOWERS
THREATENED THE SOUTHEASTERN TAF SITES EARLY. FURTHER NORTH, THERE IS
ONLY A SLIGHT CHANCE OF ANY ACTIVITY. ALL THE TAFS ARE VFR WITH SOME
CUMULUS EARLY AND THEN MID AND HIGH CLOUDS RECEDING SOUTHWARD TONIGHT.
MAINLY HIGH CLOUDS WITH PERHAPS A FEW CUMULUS ARE EXPECTED ON
FRIDAY. DRIER AIR IS EXPECTED TO MOVE DOWN FROM THE NORTH TONIGHT,
SO WE DON`T FORECAST ANY OVERNIGHT VISIBILITY RESTRICTIONS.
REGARDING WINDS, THE LATEST MODELS SHOW THEM PICKING UP FROM OUT OF
THE WEST EARLY IN THE TAF PERIOD WITH SOME GUSTS ABOVE 20 KT
POSSIBLE, THEN THEY SHOULD RELAX THIS EVENING BEFORE SHIFTING TO THE
NORTH OVERNIGHT THANKS TO A SECONDARY COLD FRONT. GENERALLY, WINDS
SHOULD BE RATHER GENTLE ON FRIDAY.
A SEA BREEZE HAD DEVELOPED AT ACY EARLIER TODAY, BUT WE THINK THE
STRENGTHENING WEST WIND WILL OVERWHELM IT EARLY IN THE TAF PERIOD. A
SEA BREEZE LIKELY WILL AFFECT ACY ON FRIDAY.
OUTLOOK...
FRIDAY NIGHT...MOSTLY VFR.
SATURDAY-SATURDAY NIGHT...MAINLY VFR WITH LOWERING CLOUDS. A
SLIGHT CHANCE OF SHOWERS AND SOUTH TO SOUTHEAST WINDS AROUND 5
KNOTS.
SUNDAY-SUNDAY NIGHT...GENERALLY VFR EXPECTED, POSSIBLE MVFR CIGS,
ESPECIALLY WITH ANY SHOWERS.
MONDAY-TUESDAY...GENERALLY VFR, POSSIBLE MVFR CIGS/VSBYS,
ESPECIALLY WITH ANY SHOWERS/THUNDERSTORMS.
&&
.MARINE...
ALTHOUGH WINDS WERE QUITE LIGHT OVER THE WATERS THIS AFTERNOON, A
RESURGENT SWELL ALONG THE FAR NORTHERN WATERS REQUIRED A SHORT-FUSED
ADVISORY FOR HAZARDOUS SEAS NORTH OF MANASQUAN INLET. MODELS SHOW
THE SWELL RETREATING BY THIS EVENING, AND THEN SEAS SHOULD BE
SUB-ADVISORY AND MORE OF A MIX OF DIMINISHING SWELLS AND MODEST TO
MODERATE WIND WAVES. THAT WILL BRING WINDS AND SEAS OVER ALL WATERS
BELOW ADVISORY CRITERIA THROUGH FRIDAY.
LIGHT WINDS THROUGH THIS EVENING ARE EXPECTED TO BECOME NORTHERLY
AND PICK UP SOME AS A SECONDARY COLD FRONT DROPS ACROSS THE COASTAL
WATERS OF NEW JERSEY AND DELAWARE. FORECAST PRESSURE RISES SUPPORT A
MODERATE BUT NOT ADVISORY LEVEL WIND. WINDS SHOULD DIMINISH AGAIN ON
FRIDAY. THE WINDS MAY BECOME ONSHORE NEAR LAND.
OUTLOOK...
CONDITIONS SHOULD REMAIN BELOW ADVISORY LEVELS THROUGH SATURDAY.
HOWEVER, WINDS MAY RETURN CLOSE TO ADVISORY LEVELS STARTING
SATURDAY NIGHT INTO SUNDAY AS THE PRESSURE GRADIENT TIGHTENS
ACROSS THE WATERS AS HIGH PRESSURE PUSHES OFF THE NORTHEAST COAST.
WITH THE EASTERLY/SOUTHEASTERLY FLOW, SEAS MAY RETURN TO SMALL
CRAFT ADVISORY LEVELS DUE TO THE LONG FETCH STARTING SUNDAY AND
CONTINUING INTO TUESDAY.
&&
.FIRE WEATHER...
WE WILL MENTION IN THE FIRE WEATHER FORECAST THAN MINIMUM RELATIVE
HUMIDITY LEVELS WILL DROP TO OR BELOW 30 PERCENT ON FRIDAY AFTERNOON
FOR MUCH OF THE FORECAST AREA. WINDS AND FINE FUELS ARE NOT A
CONCERN.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 5 PM EDT THIS
AFTERNOON FOR ANZ450.
&&
$$
SYNOPSIS...ROBERTSON
NEAR TERM...DELISI
SHORT TERM...DELISI
LONG TERM...ROBERTSON/YOUNG
AVIATION...DELISI/ROBERTSON
MARINE...DELISI/ROBERTSON
FIRE WEATHER...DELISI
AREA FORECAST DISCUSSION
NWS LINCOLN IL
311 PM CDT THU MAY 16 2013
.DISCUSSION...
ISSUED 300 PM CDT THU MAY 16 2013
A STATIONARY FRONT WILL OSCILLATE NORTH AND SOUTH ACROSS ILLINOIS
OVER THE NEXT DAY AND A HALF...THEN THE FRONT SHOULD LIFT NORTH AS
A WARM FRONT FOR THE WEEKEND...PUSHING HIGHS INTO THE MID TO UPPER
80S BY SUNDAY. BANDS OF THUNDERSTORMS THAT DEVELOP THROUGH
TOMORROW WILL LIKELY BE SLOW MOVING, HEAVY RAIN PRODUCERS LIKE
TODAY`S STORMS. LOCALIZED AREAS COULD SEE SIGNIFICANT RAINFALL OF
2-3 INCHES IN A COUPLE HOURS WHILE NEARBY AREAS SEE LITTLE RAIN.
PINPOINTING THAT ACTIVITY WILL BE DIFFICULT...BUT DIURNAL TRENDS
SHOULD PUT MOST OF THE CONVECTION DURING THE AFTERNOON
TOMORROW...ESPECIALLY NEAR ANY OUTFLOW BOUNDARIES SET DOWN BY
TODAY`S STORMS.
A SLIGHT LULL IN STORMS SHOULD OCCUR THIS WEEKEND AS RIDGING IN
THE PLAINS BUILDS INTO IL. A STRONGER COLD FRONT IS EXPECTED TO
PUSH ACROSS IL ON MONDAY AND MONDAY NIGHT...BRINGING OUR BETTER
CHANCES OF THUNDERSTORMS. WE ARE IN THE SPC DAY 5 OUTLOOK FOR
STRONG TO SEVERE STORMS MON-MON NIGHT. A COOL DOWN IS PROJECTED
FOR TUES THROUGH THURSDAY BEHIND THE COLD FRONT...PULLING HIGHS
BACK INTO THE 70S...BUT STILL AT OR ABOVE NORMAL.
SHORT TERM...TONIGHT THROUGH SUNDAY.
SHOWERS AND STORMS WILL GENERALLY BE DIMINISHING AS WE HEAD INTO
THE EVENING. THE LINE OF CONVECTION MAINLY CENTERED ON A LINE
FROM RUSHVILLE TO TAYLORVILLE TO EFFINGHAM TO LAWRENCEVILLE...IS
EXPECTED TO LIFT NORTH THIS EVENING. THE RAP MODEL IS SHOWING THE
INSTABILITY AXIS FOLLOWING THE SAME PROGRESSION...WITH SOME SHOWER
ACTIVITY DEVELOPING DURING THAT TIME. IN THE LAST HOUR...PRECIP
COVERAGE AND UPDRAFT INTENSITY HAVE ALREADY BEGUN DIMINISHING OR
WEAKENING RESPECTIVELY. RADAR LOOPS SHOW VARIOUS OUTFLOW
BOUNDARIES MOVING NORTH ACROSS OUR COUNTIES...AND MAY END UP BEING
A FOCUS FOR EVENING SHOWERS ALONG AND NORTH OF I-72.
STILL...COVERAGE WILL BE ISOLATED IN GENERAL.
FRIDAY MORNING...THE LOCATION OF THE BEST INSTABILITY WILL BE
ALONG AND NORTH OF I-74...SO ANY MORNING CONVECTION ON FRIDAY MAY
BE FOCUSED IN THAT AREA. DURING THE AFTERNOON...AN UPPER LOW
PRESSURE WAVE IS FORECAST TO LIFT NORTHEAST ACROSS IL...IN CONCERT
WITH INCREASING MOISTURE AND INSTABILITY AS THE STATIONARY FRONT
OSCILLATES NORTHWARD WITH THE WAVE. COVERAGE OF STORMS SHOULD BE
MORE THAN TODAY...BASED ON THE SUPPORT OF THE UPPER WAVE AND JET
DYNAMICS. ANY SUNSHINE THAT HEATS UP THE BOUNDARY LAYER WILL HELP
TO CREATE A FEW STRONG UPDRAFTS WITH SMALL HAIL, GUSTY WINDS, AND
VERY HEAVY RAINFALL.
THE STORMS MAY LINGER INTO THE EVENING EAST OF I-57...BUT SHOULD
DIMINISH BY MIDNIGHT. BY 12Z SAT MORNING...THE UPPER LOW IS
FORECAST TO BE CENTERED IN SOUTHERN INDIANA...WHICH WILL HELP PUT
PRECIP CHANCES MAINLY IN OUR SOUTHEAST COUNTIES ALONG AND SOUTHEAST
OF A LINE FROM SHELBYVILLE TO PARIS. THE SLOW DEPARTURE OF THE LOW
WILL KEEP CHANCES OF SHOWERS AND STORMS THROUGH SATURDAY AFTERNOON
IN THE SOUTHEAST.
THE WARM FRONT DEPARTING INTO NORTHERN IL FOLLOWED BY RIDGING AT
THE SURFACE AND ALOFT SATURDAY NIGHT AND SUNDAY SHOULD HELP MAKE
MOST AREAS DRY FOR THE LAST HALF OF THE WEEKEND. THE ADDITIONAL
SUNSHINE ON SUNDAY ALONG WITH DEEPER WARM AIR WILL HELP PUSH HIGH
TEMPS INTO THE MID TO UPPER 80S...WITH MUGGY DEWPOINTS IN THE
UPPER 60S TO NEAR 70. HEAT INDEX READINGS SUNDAY AFTERNOON WILL
CLIMB INTO THE 90S.
LONG TERM...MONDAY THROUGH THURSDAY.
ON MONDAY...AN OCCLUDING LOW PRESSURE PRESSURE SYSTEM IN THE
EASTERN DAKOTAS WILL CREATE SOME WARM FRONTOGENESIS TO THE
SOUTHEAST OF THE LOW ACROSS OUR NORTHERN COUNTIES. THAT WILL
CREATE A FOCUS FOR CONVECTION BY MONDAY AFTERNOON. MONDAY
NIGHT...A COLD FRONT WILL MOVE ACROSS IL PRODUCING STRONG TO
SEVERE STORMS AS ML-CAPE VALUES CLIMB TO NEAR 2K J/KG. BULK SHEAR
IS EXPECTED TO REACH OVER 40KT AS WELL...SO EMBEDDED SUPERCELLS
WILL BE POSSIBLE IN THE LINE OF STORMS THAT MOVES THROUGH.
STORMS ARE EXPECTED TO LINGER INTO TUESDAY AS THE UPPER COLD POOL
SLOWLY MAKES PROGRESS INTO ILLINOIS. WE KEPT LIKELY POPS SOUTHEAST
OF I-72...AND CHANCE ELSEWHERE. TUESDAY NIGHT PRECIP COVERAGE
SHOULD DIMINISH...WITH CHANCE POPS STILL IN PLACE ACROSS THE
BOARD. AN ELONGATED SURFACE TROUGH IS PROJECTED TO LINGER ACROSS
NORTHERN ILLINOIS INTO WED AS THE OCCLUDED UPPER LOW BECOMES MORE
OF AN OPEN WAVE AND SEND A SURFACE LOW EASTWARD ACROSS WISCONSIN.
THAT PROGRESSION WILL KEEP SCATTERED SHOWERS POSSIBLE AS FAR
SOUTH AS CENTRAL ILLINOIS THROUGH THURSDAY...ESPECIALLY EAST OF
I-55. PRECIP AMOUNTS MID WEEK SHOULD REMAIN LIGHT...BUT STILL
CLOUDS AND COOLER AIR WILL KEEP HIGH TEMPS BACK IN THE
70S...CLOSER TO NORMAL.
SHIMON
&&
.AVIATION...
ISSUED 1225 PM CDT THU MAY 16 2013
POP-UP NATURE OF SHOWERS/STORMS THIS AFTERNOON WILL BE A CHALLENGE
IN GOING WITH ANYTHING MORE THAN VCTS. ONE LINE OF STORMS WAS
LOCATED JUST SOUTH OF KSPI/KTAZ BUT REMAINING STATIONARY...SO WILL
NOT ADD A PREVAILING TSRA AT KSPI YET. MANY OF THE STORMS SHOULD
FADE WITH SUNSET...AND HAVE GONE WITH LARGELY DRY CONDITIONS AT
ALL TAF SITES MUCH OF THE NIGHT. LATEST HIGH- RESOLUTION GUIDANCE
SUGGESTING SOME LATE NIGHT DEVELOPMENT NEAR KPIA/KBMI...AND HAVE
PUT SOME VCTS BACK THERE...ALTHOUGH MAIN CONCERN LATE NIGHT WILL
BE WITH AREAS OF MVFR FOG. ON FRIDAY MORNING...POTENTIAL EXISTS
FOR ADDITIONAL SHOWERS/STORMS TO LIFT UP FROM THE SOUTH...AND HAVE
MENTIONED VCTS AT KSPI/KDEC AFTER 15Z.
GEELHART
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
659 PM EDT THU MAY 16 2013
.SYNOPSIS...
ISSUED AT 655 PM EDT THU MAY 16 2013
A FRONTAL BOUNDARY WHICH HAS BROUGHT SHOWERS AND THUNDERSTORMS TO
PORTIONS OF SOUTHERN INDIANA AND OHIO TODAY WILL BEGIN TO SHIFT
NORTH BY FRIDAY AFTERNOON WHICH WILL BRING A LOW CHANCE OF SHOWERS
AND THUNDERSTORMS TO AREAS SOUTH OF US 30. SHOWER AND THUNDERSTORM
CHANCES WILL PERSIST THROUGH THE WEEKEND AS THE FRONTAL BOUNDARY REMAINS
ACROSS THE AREA. ABOVE NORMAL TEMPERATURES ARE EXPECTED LATE THIS
WEEK INTO THIS WEEKEND. CHANCES FOR SHOWERS AND THUNDERSTORMS
INCREASE EARLY NEXT WEEK AS A STORM SYSTEM APPROACHES FROM THE
WEST.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
HIGH PRESSURE HAS KEPT BULK OF MSTR JUST FAR ENOUGH SOUTH OF THE
AREA TODAY TO ALLOW FOR GENERALLY DRY CONDITIONS AND TEMPS MOVING
WELL THROUGH THE 70S IN MOST SPOTS. A FEW LIGHT SHOWERS/SPRINKLES
WERE NOTED ALONG FIRST OF 2 SFC THETA E GRADIENTS ACROSS FAR
SOUTHERN COUNTIES. THIS AREA IS EXPECTED TO SHIFT SOUTH OVER THE
NEXT SEVERAL HOURS AND REMOVE ANY CHANCE FOR PRECIP FOR THE
REMAINDER OF THE NIGHT. SECONDARY GRADIENT WAS LOCATED FURTHER
SOUTH ACROSS SOUTHERN INDIANA WHERE CONVECTION HAS BEEN ONGOING
MUCH OF THE DAY. MODELS TEND TO SUGGEST THAT THIS SECONDARY AREA
OF MSTR/GREATER LIFT SUPPORT WITH MAIN SFC BOUNDARY WILL BRING
INCREASING CHANCES FOR SHOWERS AND STORMS ON FRIDAY. IT WOULD
APPEAR THAT MOST FAVORABLE TIMING WOULD BE MID TO LATE AFTERNOON
FRIDAY IN FAR SW SECTIONS WITH PROGRESSION NE HAMPERED SOMEWHAT BY
DRY AIR/SEMI DRY GROUND CONDITIONS. IF NEW RUN OF SPC 4KM WRF IS
FOLLOWED...CONVECTION WOULD NOT ARRIVE UNTIL AFTER 00Z SAT. HAVE
ADJUSTED GRIDS TO REFLECT THIS WITH SLGT CHC TO CHC POPS CONFINED
TO AFTERNOON.
CLOUD COVER WILL BE ON THE INCREASE...WHICH WILL BUT A DAMPER ON
POTENTIAL CLIMB IN HIGHS. THAT BEING SAID...HIGHS SHOULD STILL END
UP ABOVE NORMAL CLIMBING INTO THE MID AND UPPER 70S.
&&
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
WATER VAPOR IMAGERY AND LATEST RAP ANALYSIS THAT IS DEPICTING MID
LEVEL CIRCULATION MOVING EASTWARD ACROSS THE SOUTHERN PLAINS THIS
AFTERNOON WILL HAVE AN IMPACT ON THE BEGINNING OF THE EXTENDED
FCST PERIOD AS IT MOVES ACROSS THE TN VALLEY. THIS WILL ACT ON
STATIONARY SFC BOUNDARY IN ADVECTING MOISTURE IN AN OVERRUNNING
FASHION BACK NORTH OF THE BOUNDARY AND LEND SUPPORT TO WIDELY
SCATTERED CONVECTION OVER THE SW HALF OF THE CWA. FOCUS WILL THEN
SHIFT TO AMPLIFICATION OF THE UPPER LEVEL PATTERN AS STRONG JET
DYNAMICS CURRENTLY WELL OUT IN THE PACIFIC ARE PROGGED BY MEDIUM
RANGE MODELS TO COME ONSHORE AND DEVELOP DEEP UPPER TROF OVER THE
WESTERN US. THIS WILL INDUCE DOWNSTREAM RIDGING THAT WILL BUILD
INTO THE REGION SUN/MON BRINGING WARMER AND MAINLY DRY CONDITIONS
TO THE AREA. WESTERN CONUS UPPER TROF THEN EXPECTED TO BECOME
VERTICALLY STACKED CLOSED SYSTEM IN THE NORTHERN PLAINS WHICH
MODELS ARE STRUGGLING WITH TIMING OF THE EVENTUAL EJECTION OF THIS
SYSTEM INTO OUR AREA. AS EXPECTED OVERALL TREND CONTINUES TO BE
SLOWER WITH ARRIVAL OF MAIN SYSTEM NOW DELAYED TO TUE/WED
TIMEFRAME AND BRINGING WITH IT THE BEST CHANCES FOR PRECIP. PRIOR
TO ITS ARRIVAL...BECOMING MORE AND MORE DIFFICULT TO PICK OUT
MODELS HANDLING OF INCREASINGLY DIFFUSE SFC BOUNDARY BUT
INDICATIONS ARE BOUNDARY WILL LIFT NORTH OF THE AREA IN
CONJUNCTION WITH UPPER RIDGE MOVING OVER THE AREA WHICH SHOULD
LEAVE MUCH OF THE FORECAST AREA IN A CAPPED WARM SECTOR SUN/MON.
LOW CONFIDENCE IN ANY ONE PARTICULAR SCENARIO WITH THIS SETUP BUT
WILL STILL INJECT A PERIOD OR TWO OF DRY WEATHER TO REFLECT THIS.
ANTICIPATE TEMPS WELL INTO THE 80S ON MONDAY DEPENDING ON AMOUNT
OF SUN...BUMPED ALLBLEND UP A DEGREE TO START UPWARD TREND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 125 PM EDT THU MAY 16 2013
MAIN FLUX OF MOISTURE AND LIFT TO REMAIN REMOVED TO THE SOUTH OF
BOTH TAF SITES THROUGH THE PERIOD. THIS WILL ALLOW FOR VFR
CONDITIONS ACROSS THE ARE WITH OCCASIONAL MID/HIGH CLOUDS AND
WINDS 10 KNOTS OR LESS.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...BENTLEY
SHORT TERM...FISHER
LONG TERM...JAL
AVIATION...FISHER
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
656 PM EDT THU MAY 16 2013
.SYNOPSIS...
ISSUED AT 1031 AM EDT THU MAY 16 2013
A FRONTAL BOUNDARY WHICH HAS BROUGHT SHOWERS AND THUNDERSTORMS TO
PORTIONS OF SOUTHERN INDIANA AND OHIO TODAY WILL BEGIN TO SHIFT
NORTH BY FRIDAY AFTERNOON WHICH WILL BRING A LOW CHANCE OF SHOWERS
AND THUNDERSTORMS TO AREAS SOUTH OF US 30. SHOWER AND THUNDERSTORM
CHANCES WILL PERSIST THROUGH THE WEEKEND AS THE FRONTAL BOUNDARY REMAINS
ACROSS THE AREA. ABOVE NORMAL TEMPERATURES ARE EXPECTED LATE THIS
WEEK INTO THIS WEEKEND. CHANCES FOR SHOWERS AND THUNDERSTORMS
INCREASE EARLY NEXT WEEK AS A STORM SYSTEM APPROACHES FROM THE
WEST.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
HIGH PRESSURE HAS KEPT BULK OF MSTR JUST FAR ENOUGH SOUTH OF THE
AREA TODAY TO ALLOW FOR GENERALLY DRY CONDITIONS AND TEMPS MOVING
WELL THROUGH THE 70S IN MOST SPOTS. A FEW LIGHT SHOWERS/SPRINKLES
WERE NOTED ALONG FIRST OF 2 SFC THETA E GRADIENTS ACROSS FAR
SOUTHERN COUNTIES. THIS AREA IS EXPECTED TO SHIFT SOUTH OVER THE
NEXT SEVERAL HOURS AND REMOVE ANY CHANCE FOR PRECIP FOR THE
REMAINDER OF THE NIGHT. SECONDARY GRADIENT WAS LOCATED FURTHER
SOUTH ACROSS SOUTHERN INDIANA WHERE CONVECTION HAS BEEN ONGOING
MUCH OF THE DAY. MODELS TEND TO SUGGEST THAT THIS SECONDARY AREA
OF MSTR/GREATER LIFT SUPPORT WITH MAIN SFC BOUNDARY WILL BRING
INCREASING CHANCES FOR SHOWERS AND STORMS ON FRIDAY. IT WOULD
APPEAR THAT MOST FAVORABLE TIMING WOULD BE MID TO LATE AFTERNOON
FRIDAY IN FAR SW SECTIONS WITH PROGRESSION NE HAMPERED SOMEWHAT BY
DRY AIR/SEMI DRY GROUND CONDITIONS. IF NEW RUN OF SPC 4KM WRF IS
FOLLOWED...CONVECTION WOULD NOT ARRIVE UNTIL AFTER 00Z SAT. HAVE
ADJUSTED GRIDS TO REFLECT THIS WITH SLGT CHC TO CHC POPS CONFINED
TO AFTERNOON.
CLOUD COVER WILL BE ON THE INCREASE...WHICH WILL BUT A DAMPER ON
POTENTIAL CLIMB IN HIGHS. THAT BEING SAID...HIGHS SHOULD STILL END
UP ABOVE NORMAL CLIMBING INTO THE MID AND UPPER 70S.
&&
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
WATER VAPOR IMAGERY AND LATEST RAP ANALYSIS THAT IS DEPICTING MID
LEVEL CIRCULATION MOVING EASTWARD ACROSS THE SOUTHERN PLAINS THIS
AFTERNOON WILL HAVE AN IMPACT ON THE BEGINNING OF THE EXTENDED
FCST PERIOD AS IT MOVES ACROSS THE TN VALLEY. THIS WILL ACT ON
STATIONARY SFC BOUNDARY IN ADVECTING MOISTURE IN AN OVERRUNNING
FASHION BACK NORTH OF THE BOUNDARY AND LEND SUPPORT TO WIDELY
SCATTERED CONVECTION OVER THE SW HALF OF THE CWA. FOCUS WILL THEN
SHIFT TO AMPLIFICATION OF THE UPPER LEVEL PATTERN AS STRONG JET
DYNAMICS CURRENTLY WELL OUT IN THE PACIFIC ARE PROGGED BY MEDIUM
RANGE MODELS TO COME ONSHORE AND DEVELOP DEEP UPPER TROF OVER THE
WESTERN US. THIS WILL INDUCE DOWNSTREAM RIDGING THAT WILL BUILD
INTO THE REGION SUN/MON BRINGING WARMER AND MAINLY DRY CONDITIONS
TO THE AREA. WESTERN CONUS UPPER TROF THEN EXPECTED TO BECOME
VERTICALLY STACKED CLOSED SYSTEM IN THE NORTHERN PLAINS WHICH
MODELS ARE STRUGGLING WITH TIMING OF THE EVENTUAL EJECTION OF THIS
SYSTEM INTO OUR AREA. AS EXPECTED OVERALL TREND CONTINUES TO BE
SLOWER WITH ARRIVAL OF MAIN SYSTEM NOW DELAYED TO TUE/WED
TIMEFRAME AND BRINGING WITH IT THE BEST CHANCES FOR PRECIP. PRIOR
TO ITS ARRIVAL...BECOMING MORE AND MORE DIFFICULT TO PICK OUT
MODELS HANDLING OF INCREASINGLY DIFFUSE SFC BOUNDARY BUT
INDICATIONS ARE BOUNDARY WILL LIFT NORTH OF THE AREA IN
CONJUNCTION WITH UPPER RIDGE MOVING OVER THE AREA WHICH SHOULD
LEAVE MUCH OF THE FORECAST AREA IN A CAPPED WARM SECTOR SUN/MON.
LOW CONFIDENCE IN ANY ONE PARTICULAR SCENARIO WITH THIS SETUP BUT
WILL STILL INJECT A PERIOD OR TWO OF DRY WEATHER TO REFLECT THIS.
ANTICIPATE TEMPS WELL INTO THE 80S ON MONDAY DEPENDING ON AMOUNT
OF SUN...BUMPED ALLBLEND UP A DEGREE TO START UPWARD TREND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 125 PM EDT THU MAY 16 2013
MAIN FLUX OF MOISTURE AND LIFT TO REMAIN REMOVED TO THE SOUTH OF
BOTH TAF SITES THROUGH THE PERIOD. THIS WILL ALLOW FOR VFR
CONDITIONS ACROSS THE ARE WITH OCCASIONAL MID/HIGH CLOUDS AND
WINDS 10 KNOTS OR LESS.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...STEINWEDEL/KG
SHORT TERM...FISHER
LONG TERM...JAL
AVIATION...FISHER
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
230 PM EDT THU MAY 16 2013
.SYNOPSIS...
ISSUED AT 1031 AM EDT THU MAY 16 2013
A FEW LIGHT SHOWERS OR ISOLATED THUNDERSTORMS COULD SKIM THE FAR
SOUTHWEST PORTION OF THE AREA THIS AFTERNOON. OTHERWISE, MOSTLY
DRY CONDITIONS ARE EXPECTED TODAY INTO FRIDAY MORNING, AS HIGH
PRESSURE BUILDS INTO THE GREAT LAKES FORCING A FRONTAL BOUNDARY
SOUTH INTO CENTRAL INDIANA. THIS FRONT IS EXPECTED TO BUCKLE BACK
NORTH LATER FRIDAY INTO THE WEEKEND WITH A LOW CHANCE FOR SHOWERS
AND THUNDERSTORMS MAINLY SOUTH OF ROUTE 30 IN INDIANA AND MICHIGAN
EACH DAY. ABOVE NORMAL TEMPERATURES ARE EXPECTED LATE THIS WEEK
INTO THIS WEEKEND. CHANCES FOR SHOWERS AND THUNDERSTORMS INCREASE
EARLY NEXT WEEK AS A STORM SYSTEM APPROACHES FROM THE WEST.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
HIGH PRESSURE HAS KEPT BULK OF MSTR JUST FAR ENOUGH SOUTH OF THE
AREA TODAY TO ALLOW FOR GENERALLY DRY CONDITIONS AND TEMPS MOVING
WELL THROUGH THE 70S IN MOST SPOTS. A FEW LIGHT SHOWERS/SPRINKLES
WERE NOTED ALONG FIRST OF 2 SFC THETA E GRADIENTS ACROSS FAR
SOUTHERN COUNTIES. THIS AREA IS EXPECTED TO SHIFT SOUTH OVER THE
NEXT SEVERAL HOURS AND REMOVE ANY CHANCE FOR PRECIP FOR THE
REMAINDER OF THE NIGHT. SECONDARY GRADIENT WAS LOCATED FURTHER
SOUTH ACROSS SOUTHERN INDIANA WHERE CONVECTION HAS BEEN ONGOING
MUCH OF THE DAY. MODELS TEND TO SUGGEST THAT THIS SECONDARY AREA
OF MSTR/GREATER LIFT SUPPORT WITH MAIN SFC BOUNDARY WILL BRING
INCREASING CHANCES FOR SHOWERS AND STORMS ON FRIDAY. IT WOULD
APPEAR THAT MOST FAVORABLE TIMING WOULD BE MID TO LATE AFTERNOON
FRIDAY IN FAR SW SECTIONS WITH PROGRESSION NE HAMPERED SOMEWHAT BY
DRY AIR/SEMI DRY GROUND CONDITIONS. IF NEW RUN OF SPC 4KM WRF IS
FOLLOWED...CONVECTION WOULD NOT ARRIVE UNTIL AFTER 00Z SAT. HAVE
ADJUSTED GRIDS TO REFLECT THIS WITH SLGT CHC TO CHC POPS CONFINED
TO AFTERNOON.
CLOUD COVER WILL BE ON THE INCREASE...WHICH WILL BUT A DAMPER ON
POTENTIAL CLIMB IN HIGHS. THAT BEING SAID...HIGHS SHOULD STILL END
UP ABOVE NORMAL CLIMBING INTO THE MID AND UPPER 70S.
&&
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
WATER VAPOR IMAGERY AND LATEST RAP ANALYSIS THAT IS DEPICTING MID
LEVEL CIRCULATION MOVING EASTWARD ACROSS THE SOUTHERN PLAINS THIS
AFTERNOON WILL HAVE AN IMPACT ON THE BEGINNING OF THE EXTENDED
FCST PERIOD AS IT MOVES ACROSS THE TN VALLEY. THIS WILL ACT ON
STATIONARY SFC BOUNDARY IN ADVECTING MOISTURE IN AN OVERRUNNING
FASHION BACK NORTH OF THE BOUNDARY AND LEND SUPPORT TO WIDELY
SCATTERED CONVECTION OVER THE SW HALF OF THE CWA. FOCUS WILL THEN
SHIFT TO AMPLIFICATION OF THE UPPER LEVEL PATTERN AS STRONG JET
DYNAMICS CURRENTLY WELL OUT IN THE PACIFIC ARE PROGGED BY MEDIUM
RANGE MODELS TO COME ONSHORE AND DEVELOP DEEP UPPER TROF OVER THE
WESTERN US. THIS WILL INDUCE DOWNSTREAM RIDGING THAT WILL BUILD
INTO THE REGION SUN/MON BRINGING WARMER AND MAINLY DRY CONDITIONS
TO THE AREA. WESTERN CONUS UPPER TROF THEN EXPECTED TO BECOME
VERTICALLY STACKED CLOSED SYSTEM IN THE NORTHERN PLAINS WHICH
MODELS ARE STRUGGLING WITH TIMING OF THE EVENTUAL EJECTION OF THIS
SYSTEM INTO OUR AREA. AS EXPECTED OVERALL TREND CONTINUES TO BE
SLOWER WITH ARRIVAL OF MAIN SYSTEM NOW DELAYED TO TUE/WED
TIMEFRAME AND BRINGING WITH IT THE BEST CHANCES FOR PRECIP. PRIOR
TO ITS ARRIVAL...BECOMING MORE AND MORE DIFFICULT TO PICK OUT
MODELS HANDLING OF INCREASINGLY DIFFUSE SFC BOUNDARY BUT
INDICATIONS ARE BOUNDARY WILL LIFT NORTH OF THE AREA IN
CONJUNCTION WITH UPPER RIDGE MOVING OVER THE AREA WHICH SHOULD
LEAVE MUCH OF THE FORECAST AREA IN A CAPPED WARM SECTOR SUN/MON.
LOW CONFIDENCE IN ANY ONE PARTICULAR SCENARIO WITH THIS SETUP BUT
WILL STILL INJECT A PERIOD OR TWO OF DRY WEATHER TO REFLECT THIS.
ANTICIPATE TEMPS WELL INTO THE 80S ON MONDAY DEPENDING ON AMOUNT
OF SUN...BUMPED ALLBLEND UP A DEGREE TO START UPWARD TREND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 125 PM EDT THU MAY 16 2013
MAIN FLUX OF MOISTURE AND LIFT TO REMAIN REMOVED TO THE SOUTH OF
BOTH TAF SITES THROUGH THE PERIOD. THIS WILL ALLOW FOR VFR
CONDITIONS ACROSS THE ARE WITH OCCASIONAL MID/HIGH CLOUDS AND
WINDS 10 KNOTS OR LESS.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...STEINWEDEL/KG
SHORT TERM...FISHER
LONG TERM...JAL
AVIATION...FISHER
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS JACKSON KY
125 PM EDT THU MAY 16 2013
.UPDATE...
ISSUED AT 1244 PM EDT THU MAY 16 2013
ISOLATED SHOWERS AND THUNDERSTORMS HAVE DEVELOPED ACROSS THE NORTHERN
PART OF THE FORECAST AREA. CURRENT TRENDS AND NEAR TERM GUIDANCE
SUPPORTS IDEA OF KEEPING THE GREATEST SHOWER AND THUNDERSTORM
COVERAGE IN THE NORTH...WITH INCREASING COVERAGE THROUGH MID
AFTERNOON. CONVECTION WILL BE SLOWER TO DEVELOP IN THE SOUTH...AND
HAVE INCREASED MAXIMUM TEMPERATURES WHERE PRECIPITATION WILL HOLD OFF
FOR MOST IF NOT ALL OF THE DAY. NDFD AND ZFP HAVE BEEN UPDATED.
UPDATE ISSUED AT 1046 AM EDT THU MAY 16 2013
CONVECTION ASSOCIATED WITH THE SURFACE FRONT OVER OH HAS MADE LITTLE
SOUTHWARD PROGRESS THIS MORNING. HOWEVER...A BOUNDARY FROM SOUTHERN
OH CONVECTION HAS MOVED SOUTH INTO KY...AND THIS IS INTERACTING WITH
ENERGY ROTATING NORTHEAST FROM THE MID LEVEL LOW OVER OK. SHOWERS AND
THUNDERSTORMS HAVE BEEN DEVELOPING FROM SDF EAST TO SOUTH OF LEX.
THE 12Z HRRR IS HANDLING THIS FAIRLY WELL...AND THE 12Z NAM IS ALSO
SHOWING THIS. BASED ON CURRENT ANALYSIS...TRENDS AND LATEST MODEL
GUIDANCE HAVE MADE ADJUSTMENTS TO PRECIPITATION CHANCES FOR TODAY. HAVE
INCREASED COVERAGE IN THE CENTRAL PART OF THE AREA TO SCATTERED WITH
A 30 PERCENT CHANCE AND HAVE DECREASED THE PROBABILITY IN THE FAR
SOUTH FROM 40 PERCENT TO 30 PERCENT. WILL CONTINUE TO CARRY THE
HIGHEST SHOWER AND THUNDERSTORM CHANCES IN THE NORTH.
UPDATE ISSUED AT 857 AM EDT THU MAY 16 2013
CLOUDS HAVE INCREASED QUICKLY THIS MORNING...AND HAVE UPDATED THE
NDFD AND ZFP TO REFLECT THIS. MOSTLY CLOUDY SKIES NOW FORECAST ACROSS
THE ENTIRE AREA FOR TODAY. HRRR IS HANDLING CURRENT CONVECTION FAIRLY
WELL. 11Z HRRR POINTS TOWARDS A NORTH TO SOUTH RAIN PROBABILITY
CHANCE THIS AFTERNOON...WITH BEST CHANCE IN THE NORTH. WILL TAKE A
LOOK AT INCOMING 12Z DATA FOR ANY POSSIBLE UPDATES TO THE RAIN
PROBABILITIES FOR THIS AFTERNOON.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 253 AM EDT THU MAY 16 2013
THERE ARE TWO MAIN INGREDIENTS TO THIS FORECAST WHICH INDIVIDUALLY
AND COLLECTIVELY ADD SOME DIFFICULTY TO THE FORECAST. THERE IS A COLD
FRONT SOUTH OF THE GREAT LAKES WHICH IS SAGGING TO THE SOUTH. THERE
IS ALSO AN UPPER LOW OVER OKLAHOMA EMBEDDED IS A WEAKER SOUTHERLY
STREAM. THESE TWO SYSTEMS ARE BOTH GOING TO BE EFFECTING THE WEATHER
OVER THE AREA OVER THE NEXT TWO DAYS. AT 230 AM THERE WAS A LINE OF
SHOWER AND THUNDERSTORMS WHICH EXTENDED FROM SOUTHWEST PENNSYLVANIA AND
THEN PASSED SOUTH OF COLUMBUS AND THEN ACROSS DAYTON. THIS SYSTEM
WILL BE SAGGING TO THE SOUTH. THE BIG QUESTION IS HOW FAR SOUTH WILL
THE FRONT MOVE. THE NAM STALLS THIS FRONT OUT ALONG THE OHIO RIVER
VALLEY. AS A RESULT...KEPT THE BEST CHANCE FOR RAIN TODAY AND
TONIGHT NORTH OF I 64 IN THE BLUEGRASS. THE MODELS ARE ALSO
GENERATING SOME ENERGY OUT AHEAD OF THE UPPER LOW WHICH WILL BE
MOVING TO THE EAST THE AREA SOUTH OF I 64 WILL BE IN THE GENERALLY
UNSTABLE WARM SECTOR TODAY AND TONIGHT WITH SOME ENERGY SPINNING
AROUND THE UPPER LOW WHICH MAY MOVE INTO THE AREA LATER TODAY. THIS
IS MOST LIKELY GOING TO EFFECT THE AREA SOUTH OF THE HAL ROGERS
PARKWAY. SO THERE IS A SLOT ACROSS THE CENTRAL PORTION OF EASTERN
KENTUCKY WHICH SHOULD BE SOUTH OF THE INFLUENCE OF THE FRONT AND
NORTH OF THE INFLUENCE OF THE UPPER LOW. THE ONE THING THAT IS A BIT
OF A WILD CARD IS IF THE THUNDERSTORMS TO THE NORTH ARE ABLE TO
CREATE A COLD POOL TODAY WHICH PROPAGATES SOUTH ACROSS EASTERN
KENTUCKY. THE NAM BUFFER SOUNDING HAS A LIFTED INDEX OF AROUND -5
THIS AFTERNOON...SO IF A COLD POOL DOES MOVE INTO THE AREA...THERE
WILL BE PLENTY OF INSTABILITY TO KEEP IT GOING. THE SCENARIO IS NOT
IN THE FORECAST...HOWEVER BEARS WATCHING.THERE SHOULD BE PLENTY OF
CLOUDS TODAY...HOWEVER THE LOWER LAYERS ARE FAIRLY DRY AND IT SHOULD
TAKE A WHILE TO BE ABLE TO MOISTEN THEM UP ENOUGH FOR THE RAIN TO
REACH THE GROUND. THE TEMPERATURES WILL BE SO DEPENDENT ON HOW
EXTENSIVE THE SHOWERS WILL BE TODAY. WENT A BIT WARMER THAN THE MODEL
CONSENSUS AND BLENDED CLOSER TO THE WARMER NAM MOS FOR TODAY AND
TOMORROW.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 253 AM EDT THU MAY 16 2013
MODE LS ARE IN FAIR AGREEMENT...BETTER WITH RELATIVELY SLOW BUT
PROGRESSIVE UPPER AIR PATTERN THAN WITH SURFACE FEATURES. EXTENDED
STARTS OUT WITH AN OPEN WAVE TRACKING EASTWARD ACROSS THE OHIO/TN
VALLEY REGIONS THROUGH THE WEEKEND. SHORTWAVE RIDGE THEN TRANSITS
THE REGION MONDAY BEFORE SLOW MOVING LOW PRESSURE SYSTEM OVER THE
NORTH CENTRAL PLAINS SHIFTS INTO THE MIDWEST...OR GREAT LAKES BY THE
END OF THE FORECAST WINDOW. WE FALL UNDER A SOUTHWEST FLOW REGIME
ALOFT DURING THE INTERIM. ECMWF...WITH SUPPORT FROM THE CANADIAN
APPEARS MORE ORGANIZED AND FURTHER SOUTH WITH THE UPPER LOW MOVING
OUT OF THE PLAINS AND INTO THE MIDWEST VERSUS THE GFS WHICH KEEPS
THE UPPER LOW UP OVER THE NORTHERN TIER. MODELS DIVERGE EVEN MORE
SIGNIFICANTLY JUST BEYOND THE END OF THE FORECAST PERIOD. TENDENCY
IS TO LEAN TOWARDS THE TYPICALLY MORE ACCURATE...RELIABLE ECMWF WITH
RESPECT TO THE EVOLUTION OF THE UPPER AIR PATTERN.
AT THE SURFACE...AGAIN MODELS DIFFER CONSIDERABLY ON THE EVENTUAL
POSITION SOUTHERN EXTENT OF SURFACE COLD FRONTAL BOUNDARY ACROSS THE
OHIO VALLEY EARLY IN THE FORECAST. THE NAM/GFS BRINGS THE BOUNDARY
AS FAR SOUTH AS AN IND TO DAY LINE LATE THIS AFTERNOON AND/OR EARLY
FRIDAY MORNING RESPECTIVELY. THE ECMWF BRINGS THE BOUNDARY SOUTHWARD
TO BETWEEN DAY AND CVG BY EARLY SATURDAY MORNING...APPARENTLY WITH
SUPPORT FROM THE UPPER LEVEL WAVE THAT PUSHES THROUGH THE REGION.
END RESULT IS THAT THE BOUNDARY NEVER REALLY SEEMS TO MAKE IT AS FAR
SOUTH AS THE OHIO RIVER...IN A TRUE SUMMERTIME LIKE FASHION. THIS
DOES NOT BODE WELL FOR THE OPPORTUNITY OF RAIN UNLESS CONVECTION
ALONG THE FRONTAL BOUNDARY BECOMES MORE ORGANIZED AND MANAGES TO
MAKE A SURGE SOUTHWARD INTO OUR AREA. BEST OPPORTUNITY FOR THIS...
OR JUST SHOWER AND THUNDERSTORM ACTIVITY IN GENERAL WILL COME AS THE
UPPER LEVEL WAVE OR DISTURBANCE GRADUALLY SHIFTS THROUGH THE REGION
SATURDAY AND SUNDAY. TRENDED DRIER SUNDAY NIGHT THROUGH MONDAY NIGHT
WITH UPPER LEVEL RIDGING BUILDING INTO THE AREA. THREAT OF SHOWERS
AND THUNDERSTORMS INCREASE AGAIN TOWARDS THE END OF THE FORECAST
WINDOW...TUESDAY NIGHT AND/OR WEDNESDAY AND BEYOND AS SYSTEM MORE
THAN LIKELY MAKES A MOVE TOWARDS OUR AREA OUT OF THE NORTH CENTRAL
PLAINS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 125 PM EDT THU MAY 16 2013
A STATIONARY FRONT OVER SOUTHERN OHIO WILL KEEP THE THREAT OF SHOWERS
AND THUNDERSTORMS GREATEST IN THE NORTHERN PART OF THE FORECAST
AREA...NORTH OF THE TAF SITES...THROUGH THE AFTERNOON. NUMEROUS
SHOWERS AND THUNDERSTORMS WILL AFFECT THE NORTHERN PART OF THE
FORECAST AREA...WITH LOCAL IFR CONDITIONS. FROM JKL...SOUTH TO THE TN
AND VA BORDER...THUNDERSTORMS ARE POSSIBLE LATE THIS AFTERNOON AND
EVENING...BUT COVERAGE WILL BE MUCH LESS. FOR THE SOUTHERN PART OF
THE FORECAST AREA...INCLUDING THE TAF SITES...VFR CONDITIONS ARE
EXPECTED THROUGH THE FORECAST PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...JJ
LONG TERM...RAY
AVIATION...SBH
AREA FORECAST DISCUSSION
NWS JACKSON KY
1245 PM EDT THU MAY 16 2013
.UPDATE...
ISSUED AT 1244 PM EDT THU MAY 16 2013
ISOLATED SHOWERS AND THUNDERSTORMS HAVE DEVELOPED ACROSS THE NORTHERN
PART OF THE FORECAST AREA. CURRENT TRENDS AND NEAR TERM GUIDANCE
SUPPORTS IDEA OF KEEPING THE GREATEST SHOWER AND THUNDERSTORM
COVERAGE IN THE NORTH...WITH INCREASING COVERAGE THROUGH MID
AFTERNOON. CONVECTION WILL BE SLOWER TO DEVELOP IN THE SOUTH...AND
HAVE INCREASED MAXIMUM TEMPERATURES WHERE PRECIPITATION WILL HOLD OFF
FOR MOST IF NOT ALL OF THE DAY. NDFD AND ZFP HAVE BEEN UPDATED.
UPDATE ISSUED AT 1046 AM EDT THU MAY 16 2013
CONVECTION ASSOCIATED WITH THE SURFACE FRONT OVER OH HAS MADE LITTLE
SOUTHWARD PROGRESS THIS MORNING. HOWEVER...A BOUNDARY FROM SOUTHERN
OH CONVECTION HAS MOVED SOUTH INTO KY...AND THIS IS INTERACTING WITH
ENERGY ROTATING NORTHEAST FROM THE MID LEVEL LOW OVER OK. SHOWERS AND
THUNDERSTORMS HAVE BEEN DEVELOPING FROM SDF EAST TO SOUTH OF LEX.
THE 12Z HRRR IS HANDLING THIS FAIRLY WELL...AND THE 12Z NAM IS ALSO
SHOWING THIS. BASED ON CURRENT ANALYSIS...TRENDS AND LATEST MODEL
GUIDANCE HAVE MADE ADJUSTMENTS TO PRECIPITATION CHANCES FOR TODAY. HAVE
INCREASED COVERAGE IN THE CENTRAL PART OF THE AREA TO SCATTERED WITH
A 30 PERCENT CHANCE AND HAVE DECREASED THE PROBABILITY IN THE FAR
SOUTH FROM 40 PERCENT TO 30 PERCENT. WILL CONTINUE TO CARRY THE
HIGHEST SHOWER AND THUNDERSTORM CHANCES IN THE NORTH.
UPDATE ISSUED AT 857 AM EDT THU MAY 16 2013
CLOUDS HAVE INCREASED QUICKLY THIS MORNING...AND HAVE UPDATED THE
NDFD AND ZFP TO REFLECT THIS. MOSTLY CLOUDY SKIES NOW FORECAST ACROSS
THE ENTIRE AREA FOR TODAY. HRRR IS HANDLING CURRENT CONVECTION FAIRLY
WELL. 11Z HRRR POINTS TOWARDS A NORTH TO SOUTH RAIN PROBABILITY
CHANCE THIS AFTERNOON...WITH BEST CHANCE IN THE NORTH. WILL TAKE A
LOOK AT INCOMING 12Z DATA FOR ANY POSSIBLE UPDATES TO THE RAIN
PROBABILITIES FOR THIS AFTERNOON.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 253 AM EDT THU MAY 16 2013
THERE ARE TWO MAIN INGREDIENTS TO THIS FORECAST WHICH INDIVIDUALLY
AND COLLECTIVELY ADD SOME DIFFICULTY TO THE FORECAST. THERE IS A COLD
FRONT SOUTH OF THE GREAT LAKES WHICH IS SAGGING TO THE SOUTH. THERE
IS ALSO AN UPPER LOW OVER OKLAHOMA EMBEDDED IS A WEAKER SOUTHERLY
STREAM. THESE TWO SYSTEMS ARE BOTH GOING TO BE EFFECTING THE WEATHER
OVER THE AREA OVER THE NEXT TWO DAYS. AT 230 AM THERE WAS A LINE OF
SHOWER AND THUNDERSTORMS WHICH EXTENDED FROM SOUTHWEST PENNSYLVANIA AND
THEN PASSED SOUTH OF COLUMBUS AND THEN ACROSS DAYTON. THIS SYSTEM
WILL BE SAGGING TO THE SOUTH. THE BIG QUESTION IS HOW FAR SOUTH WILL
THE FRONT MOVE. THE NAM STALLS THIS FRONT OUT ALONG THE OHIO RIVER
VALLEY. AS A RESULT...KEPT THE BEST CHANCE FOR RAIN TODAY AND
TONIGHT NORTH OF I 64 IN THE BLUEGRASS. THE MODELS ARE ALSO
GENERATING SOME ENERGY OUT AHEAD OF THE UPPER LOW WHICH WILL BE
MOVING TO THE EAST THE AREA SOUTH OF I 64 WILL BE IN THE GENERALLY
UNSTABLE WARM SECTOR TODAY AND TONIGHT WITH SOME ENERGY SPINNING
AROUND THE UPPER LOW WHICH MAY MOVE INTO THE AREA LATER TODAY. THIS
IS MOST LIKELY GOING TO EFFECT THE AREA SOUTH OF THE HAL ROGERS
PARKWAY. SO THERE IS A SLOT ACROSS THE CENTRAL PORTION OF EASTERN
KENTUCKY WHICH SHOULD BE SOUTH OF THE INFLUENCE OF THE FRONT AND
NORTH OF THE INFLUENCE OF THE UPPER LOW. THE ONE THING THAT IS A BIT
OF A WILD CARD IS IF THE THUNDERSTORMS TO THE NORTH ARE ABLE TO
CREATE A COLD POOL TODAY WHICH PROPAGATES SOUTH ACROSS EASTERN
KENTUCKY. THE NAM BUFFER SOUNDING HAS A LIFTED INDEX OF AROUND -5
THIS AFTERNOON...SO IF A COLD POOL DOES MOVE INTO THE AREA...THERE
WILL BE PLENTY OF INSTABILITY TO KEEP IT GOING. THE SCENARIO IS NOT
IN THE FORECAST...HOWEVER BEARS WATCHING.THERE SHOULD BE PLENTY OF
CLOUDS TODAY...HOWEVER THE LOWER LAYERS ARE FAIRLY DRY AND IT SHOULD
TAKE A WHILE TO BE ABLE TO MOISTEN THEM UP ENOUGH FOR THE RAIN TO
REACH THE GROUND. THE TEMPERATURES WILL BE SO DEPENDENT ON HOW
EXTENSIVE THE SHOWERS WILL BE TODAY. WENT A BIT WARMER THAN THE MODEL
CONSENSUS AND BLENDED CLOSER TO THE WARMER NAM MOS FOR TODAY AND
TOMORROW.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 253 AM EDT THU MAY 16 2013
MODE LS ARE IN FAIR AGREEMENT...BETTER WITH RELATIVELY SLOW BUT
PROGRESSIVE UPPER AIR PATTERN THAN WITH SURFACE FEATURES. EXTENDED
STARTS OUT WITH AN OPEN WAVE TRACKING EASTWARD ACROSS THE OHIO/TN
VALLEY REGIONS THROUGH THE WEEKEND. SHORTWAVE RIDGE THEN TRANSITS
THE REGION MONDAY BEFORE SLOW MOVING LOW PRESSURE SYSTEM OVER THE
NORTH CENTRAL PLAINS SHIFTS INTO THE MIDWEST...OR GREAT LAKES BY THE
END OF THE FORECAST WINDOW. WE FALL UNDER A SOUTHWEST FLOW REGIME
ALOFT DURING THE INTERIM. ECMWF...WITH SUPPORT FROM THE CANADIAN
APPEARS MORE ORGANIZED AND FURTHER SOUTH WITH THE UPPER LOW MOVING
OUT OF THE PLAINS AND INTO THE MIDWEST VERSUS THE GFS WHICH KEEPS
THE UPPER LOW UP OVER THE NORTHERN TIER. MODELS DIVERGE EVEN MORE
SIGNIFICANTLY JUST BEYOND THE END OF THE FORECAST PERIOD. TENDENCY
IS TO LEAN TOWARDS THE TYPICALLY MORE ACCURATE...RELIABLE ECMWF WITH
RESPECT TO THE EVOLUTION OF THE UPPER AIR PATTERN.
AT THE SURFACE...AGAIN MODELS DIFFER CONSIDERABLY ON THE EVENTUAL
POSITION SOUTHERN EXTENT OF SURFACE COLD FRONTAL BOUNDARY ACROSS THE
OHIO VALLEY EARLY IN THE FORECAST. THE NAM/GFS BRINGS THE BOUNDARY
AS FAR SOUTH AS AN IND TO DAY LINE LATE THIS AFTERNOON AND/OR EARLY
FRIDAY MORNING RESPECTIVELY. THE ECMWF BRINGS THE BOUNDARY SOUTHWARD
TO BETWEEN DAY AND CVG BY EARLY SATURDAY MORNING...APPARENTLY WITH
SUPPORT FROM THE UPPER LEVEL WAVE THAT PUSHES THROUGH THE REGION.
END RESULT IS THAT THE BOUNDARY NEVER REALLY SEEMS TO MAKE IT AS FAR
SOUTH AS THE OHIO RIVER...IN A TRUE SUMMERTIME LIKE FASHION. THIS
DOES NOT BODE WELL FOR THE OPPORTUNITY OF RAIN UNLESS CONVECTION
ALONG THE FRONTAL BOUNDARY BECOMES MORE ORGANIZED AND MANAGES TO
MAKE A SURGE SOUTHWARD INTO OUR AREA. BEST OPPORTUNITY FOR THIS...
OR JUST SHOWER AND THUNDERSTORM ACTIVITY IN GENERAL WILL COME AS THE
UPPER LEVEL WAVE OR DISTURBANCE GRADUALLY SHIFTS THROUGH THE REGION
SATURDAY AND SUNDAY. TRENDED DRIER SUNDAY NIGHT THROUGH MONDAY NIGHT
WITH UPPER LEVEL RIDGING BUILDING INTO THE AREA. THREAT OF SHOWERS
AND THUNDERSTORMS INCREASE AGAIN TOWARDS THE END OF THE FORECAST
WINDOW...TUESDAY NIGHT AND/OR WEDNESDAY AND BEYOND AS SYSTEM MORE
THAN LIKELY MAKES A MOVE TOWARDS OUR AREA OUT OF THE NORTH CENTRAL
PLAINS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 725 AM EDT THU MAY 16 2013
VFR CONDITIONS WILL HOLD THROUGH THE TAF FORECAST PERIOD. A THREAT
OF THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON WITH THUNDERSTORMS
MOVING FROM THE NORTH IN THE JKL AREA AND FROM THE SOUTH FOR LOZ AND
SME. THERE IS ONLY AND SLIGHT CHANCE AT JKL AND A CHANCE AT SME AND
LOZ. THERE IS TOO MUCH UNCERTAINTY TO GO WITH A PREVAILING
THUNDERSTORM GROUP AS THE THUNDERSTORMS COULD STAY NORTH OR SOUTH AND
MAY NOT IMPACT THE TAF SITES.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...JJ
LONG TERM...RAY
AVIATION...JJ
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
325 PM EDT THU MAY 16 2013
.SYNOPSIS...
HIGH PRESSURE REMAINS OFF THE COAST THROUGH THIS EVENING. A WEAK
FRONT MOVES SOUTH ACROSS VIRGINIA OVERNIGHT INTO FRIDAY
AFTERNOON...THEN STALLS OVER NORTH CAROLINA THROUGH THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
SFC HI PRES RMNS OFF THE SE CONUS CST...WHILE A WK (ILL-DEFINED)
SFC BNDRY IS DRAPED E-W INVOF MD/PA BORDER WWD INTO SRN OH VLY.
VRY WARM AIR S OF THE BNDRY W/ MNLY WSWLY WNDS (A LTL GUSTY AT
TIMES TO ABT 20 MPH). CNVTN BEGINNING TO FIRE INVOF NW VA...JUST
NNW OF CHO...W/ ONLY ISOLD PCPN FOUND TO THE ENE INTO THE INTR
PORTION FO THE LWR MD ERN SHR. CNVTN HIGH BASED (~7KFT) AND
MODIFIED SOUNDINGS ACRS NRN PORTIONS OF FA SHOWING INVERTED V IN
LWR LVLS (TO ARND 850MB). SLGT POOLING OF DEWPTS (U50S) ACRS NRN VA
SO FAR THIS AFTN. ALSO...FREEZING LVL 11.5 TO 12KFT...WILL NEED
CORES OF ANY STMS TO AOA 30KFT FOR STRONG/SVR PTNTL. LMTG FACTOR
IS DP LYRD/DOWNSLOPING W WNDS PTNTLLY MAKING IT DIFFICULT FOR STM
UPDRAFTS TO RISE SUBSTANTIALLY. MAIN THREATS - GUSTY WINDS AND
HAIL. 17Z/16 RUC GENLY HAS DECENT HANDLING ON STM DVLPMNT
ATTM...AND HV FOLLOWED FOR EVE CNVTV POPS (WHICH CONFINES STMS TO
AREAS ALG-N OF A FVX TO WAL LN). S OF THAT LN ISOLD STMS AT
BEST...BUT RIGHT NOW PROB TOO LO FOR POPS ANY HIGHER THAN 14%.
AFT EVE STMS...BNDRY SINKS S THROUGH VA AND WINDS TURN MR NLY AFT
MDNGT. LINGERING SHRAS AFT MDNGT...THOUGH POPS AOB 20% THROUGHOUT.
LO TEMPS MNLY IN THE L/M60S.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY/...
FNTL BNDRY STALLS OVR NRN VA ON FRI...W/ SFC HI PRES PASSING BY TO
THE NNE OF FA. RESULT WILL BE ONSHR SFC WNDS...AND CORRESPONDING
COOLING. WILL HAVE HIGHEST AMT OF CLDNS FM CNTRL VA ON S...AND LMT
CHC POPS TO MUCH OF THAT AREA (HIGHEST FAR SCNTRL VA INTO INTR NE
NC).
FM FRI NGT THROUGH SAT...WK LO PRES TRACKS E INTO THE CNTRL OH
VLY...RESULTING IN INCRSG MSTR INTO THE MDATLC RGN. FNTL BNDRY
RMNS S ACRS NRN NC...KEEPING ONSHR WNDS OVR MUCH OF THE FA
(THROUGH SAT). IN LEANING CLOSER TO 12Z/16 ECMWF WILL HAVE
HIGHEST (CHC) POPS INLAND FRI NGT THROUGH SAT...THOUGH WILL HAVE
VRB CLDNS OR MCLDY CONDS.
HI TEMPS FRI FM THE M/U70S AT THE CST TO L/M80S INLAND. LO TEMPS
FRI NGT FM THE M50S TO L60S. HI TEMPS SAT FM THE L/M70S AT THE
CST TO 75 TO 80F INLAND.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
A WEAK FRONTAL BOUNDARY WILL LINGER ACROSS THE MID-ATLANTIC SUNDAY
NIGHT INTO MONDAY. THIS IS IN ADDITION TO A WEAK UPPER DISTURBANCE
PASSING OVERHEAD WILL PRODUCE A CHANCE FOR SHOWERS AND
THUNDERSTORMS. AN H5 RIDGE AXIS SHOULD BUILD OVER THEN EASTERN U.S.
TUESDAY OF NEXT WEEK...THEN SLIDES OFF TO THE EAST LATE WEDNESDAY AS
THE NEXT SYSTEM BEGINS TO IMPACT THE MID-ATLANTIC. WILL MAINTAIN
SLIGHT CHC POPS ON TUESDAY DUE TO SOME UNCERTAINTY IN THE MODELS AS
TO WHETHER OR NOT THE UPPER DISTURBANCE PUSHES FAR ENOUGH OFF THE
COAST. THE NEXT SYSTEM LOOKS LIKE IT WILL BRING A GOOD CHANCE OF
SHOWERS BY LATE WEDNESDAY INTO NEXT THURSDAY. TEMPS WILL REMAIN ON
THE WARM/MILD SIDE THROUGH THE PERIOD WITH HIGHS IN THE 70S AND 80S
AND LOWS IN THE 60S.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
LOW PRESSURE CONTINUES TO TRACK THROUGH THE NORTHEAST TODAY AS AN
ATTENDANT COLD FRONT SLOWLY SAGS SWD INTO THE MID ATLANTIC. EXPECT
W/SW WINDS GENERALLY AROUND 10 KT WITH GUSTS UP TO 15 KT. AS THE
FRONT DROPS INTO NRN VA...ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON INTO THIS EVENING
ACROSS THE REGION...GENERALLY NORTH OF THE NC/VA BORDER. MVFR/IFR
VSBYS POSSIBLE IN THUNDERSTORMS. HOWEVER...CONFIDENCE IN TIMING
AND PLACEMENT OF ANY STORMS IS NOT HIGH ATTM...SO HAVE ONLY
INCLUDED TEMPO GROUP MENTIONING RAIN SHOWERS.
THE COLD FRONT WILL CONTINUE TO SLOWLY PROGRESS SWD...CROSSING THE
REGION LATE TONIGHT THROUGH FRIDAY. WINDS WILL BACK FROM THE W/SW
TO THE NW BEHIND THE FRONT...BUT REMAIN AOB 10 KT. SHOWERS AND
THUNDERSTORMS WILL AGAIN BE POSSIBLE FRI AFTERNOON/EVENING...MAINLY
ACROSS SRN VA/NRN NC. THE FRONT WILL STALL OVER THE CAROLINAS THIS
WEEKEND...WITH ADDITIONAL SHOWERS AND THUNDERSTORMS POSSIBLE.
&&
.MARINE...
WINDS WILL CONTINUE TO VEER TO THE WEST THIS AFTERNOON IN ADVANCE OF
A BACKDOOR COLD FRONT. THE FRONT WILL SLOWLY CROSS THE WATERS
TONIGHT INTO FRIDAY. WINDS WILL VEER TO THE N/NE FRIDAY BEHIND THE
FRONT...BECOMING EAST IN THE AFTERNOON...BUT WILL REMAIN BELOW SCA
THRESHOLDS. THE COLD FRONT WILL STALL OVER THE CAROLINAS THIS
WEEKEND BEFORE LIFTING NWD AS A WARM FRONT BY THE BEGINNING OF NEXT
WEEK. E/SE WINDS LESS THAN 15 KT ARE EXPECTED OVER THE WEEKEND. SEAS
MAY BUILD TO 5 FT OVER THE NORTHERN COASTAL WATERS ON SUNDAY.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ALB/MPR
NEAR TERM...ALB/MPR
SHORT TERM...MPR
LONG TERM...JDM
AVIATION...SAM/DAP
MARINE...JDM
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
314 PM EDT THU MAY 16 2013
.SYNOPSIS...
HIGH PRESSURE REMAINS OFF THE COAST THROUGH THIS EVENING. A WEAK
FRONT MOVES SOUTH ACROSS VIRGINIA OVERNIGHT INTO FRIDAY
AFTERNOON...THEN STALLS OVER NORTH CAROLINA THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
SFC HI PRES RMNS OFF THE SE CONUS CST...WHILE A WK (ILL-DEFINED)
SFC BNDRY IS DRAPED E-W INVOF MD/PA BORDER WWD INTO SRN OH VLY.
VRY WARM AIR S OF THE BNDRY W/ MNLY WSWLY WNDS (A LTL GUSTY AT
TIMES TO ABT 20 MPH). CNVTN BEGINNING TO FIRE INVOF NW VA...JUST
NNW OF CHO...W/ ONLY ISOLD PCPN FOUND TO THE ENE INTO THE INTR
PORTION FO THE LWR MD ERN SHR. CNVTN HIGH BASED (~7KFT) AND
MODIFIED SOUNDINGS ACRS NRN PORTIONS OF FA SHOWING INVERTED V IN
LWR LVLS (TO ARND 850MB). SLGT POOLING OF DEWPTS (U50S) ACRS NRN VA
SO FAR THIS AFTN. ALSO...FREEZING LVL 11.5 TO 12KFT...WILL NEED
CORES OF ANY STMS TO AOA 30KFT FOR STRONG/SVR PTNTL. LMTG FACTOR
IS DP LYRD/DOWNSLOPING W WNDS PTNTLLY MAKING IT DIFFICULT FOR STM
UPDRAFTS TO RISE SUBSTANTIALLY. MAIN THREATS - GUSTY WINDS AND
HAIL. 17Z/16 RUC GENLY HAS DECENT HANDLING ON STM DVLPMNT
ATTM...AND HV FOLLOWED FOR EVE CNVTV POPS (WHICH CONFINES STMS TO
AREAS ALG-N OF A FVX TO WAL LN). S OF THAT LN ISOLD STMS AT
BEST...BUT RIGHT NOW PROB TOO LO FOR POPS ANY HIGHER THAN 14%.
AFT EVE STMS...BNDRY SINKS S THROUGH VA AND WINDS TURN MR NLY AFT
MDNGT. LINGERING SHRAS AFT MDNGT...THOUGH POPS AOB 20% THROUGHOUT.
LO TEMPS MNLY IN THE L/M60S.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
FNTL BNDRY STALLS OVR NRN VA ON FRI...W/ SFC HI PRES PASSING BY TO
THE NNE OF FA. RESULT WILL BE ONSHR SFC WNDS...AND CORRESPONDING
COOLING. WILL HAVE HIGHEST AMT OF CLDNS FM CNTRL VA ON S...AND LMT
CHC POPS TO MUCH OF THAT AREA (HIGHEST FAR SCNTRL VA INTO INTR NE
NC).
FM FRI NGT THROUGH SAT...WK LO PRES TRACKS E INTO THE CNTRL OH
VLY...RESULTING IN INCRSG MSTR INTO THE MDATLC RGN. FNTL BNDRY
RMNS S ACRS NRN NC...KEEPING ONSHR WNDS OVR MUCH OF THE FA
(THROUGH SAT). WILL HAVE HIGHEST POPS INLAND THROUGH SAT...THOUGH
WILL HAVE VRB CLDNS OR MCLDY CONDS.
HI TEMPS FRI FM THE M/U70S AT THE CST TO L/M80S INLAND. LO TEMPS
FRI NGT FM THE M50S TO L60S. HI TEMPS SAT FM THE L/M70S AT THE
CST TO 75 TO 80F INLAND.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
A WEAK FRONTAL BOUNDARY WILL LINGER ACROSS THE MID-ATLANTIC SUNDAY
NIGHT INTO MONDAY. THIS IS IN ADDITION TO A WEAK UPPER DISTURBANCE
PASSING OVERHEAD WILL PRODUCE A CHANCE FOR SHOWERS AND
THUNDERSTORMS. AN H5 RIDGE AXIS SHOULD BUILD OVER THEN EASTERN U.S.
TUESDAY OF NEXT WEEK...THEN SLIDES OFF TO THE EAST LATE WEDNESDAY AS
THE NEXT SYSTEM BEGINS TO IMPACT THE MID-ATLANTIC. WILL MAINTAIN
SLIGHT CHC POPS ON TUESDAY DUE TO SOME UNCERTAINTY IN THE MODELS AS
TO WHETHER OR NOT THE UPPER DISTURBANCE PUSHES FAR ENOUGH OFF THE
COAST. THE NEXT SYSTEM LOOKS LIKE IT WILL BRING A GOOD CHANCE OF
SHOWERS BY LATE WEDNESDAY INTO NEXT THURSDAY. TEMPS WILL REMAIN ON
THE WARM/MILD SIDE THROUGH THE PERIOD WITH HIGHS IN THE 70S AND 80S
AND LOWS IN THE 60S.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
LOW PRESSURE CONTINUES TO TRACK THROUGH THE NORTHEAST TODAY AS AN
ATTENDANT COLD FRONT SLOWLY SAGS SWD INTO THE MID ATLANTIC. EXPECT
W/SW WINDS GENERALLY AROUND 10 KT WITH GUSTS UP TO 15 KT. AS THE
FRONT DROPS INTO NRN VA...ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON INTO THIS EVENING
ACROSS THE REGION...GENERALLY NORTH OF THE NC/VA BORDER. MVFR/IFR
VSBYS POSSIBLE IN THUNDERSTORMS. HOWEVER...CONFIDENCE IN TIMING
AND PLACEMENT OF ANY STORMS IS NOT HIGH ATTM...SO HAVE ONLY
INCLUDED TEMPO GROUP MENTIONING RAIN SHOWERS.
THE COLD FRONT WILL CONTINUE TO SLOWLY PROGRESS SWD...CROSSING THE
REGION LATE TONIGHT THROUGH FRIDAY. WINDS WILL BACK FROM THE W/SW
TO THE NW BEHIND THE FRONT...BUT REMAIN AOB 10 KT. SHOWERS AND
THUNDERSTORMS WILL AGAIN BE POSSIBLE FRI AFTERNOON/EVENING...MAINLY
ACROSS SRN VA/NRN NC. THE FRONT WILL STALL OVER THE CAROLINAS THIS
WEEKEND...WITH ADDITIONAL SHOWERS AND THUNDERSTORMS POSSIBLE.
&&
.MARINE...
WINDS WILL CONTINUE TO VEER TO THE WEST THIS AFTERNOON IN ADVANCE OF
A BACKDOOR COLD FRONT. THE FRONT WILL SLOWLY CROSS THE WATERS
TONIGHT INTO FRIDAY. WINDS WILL VEER TO THE N/NE FRIDAY BEHIND THE
FRONT...BECOMING EAST IN THE AFTERNOON...BUT WILL REMAIN BELOW SCA
THRESHOLDS. THE COLD FRONT WILL STALL OVER THE CAROLINAS THIS
WEEKEND BEFORE LIFTING NWD AS A WARM FRONT BY THE BEGINNING OF NEXT
WEEK. E/SE WINDS LESS THAN 15 KT ARE EXPECTED OVER THE WEEKEND. SEAS
MAY BUILD TO 5 FT OVER THE NORTHERN COASTAL WATERS ON SUNDAY.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ALB/MPR
NEAR TERM...ALB/MPR
SHORT TERM...MPR
LONG TERM...JDM
AVIATION...SAM/DAP
MARINE...JDM
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
236 PM EDT THU MAY 16 2013
.SYNOPSIS...
HIGH PRESSURE REMAINS OFF THE COAST THROUGH THIS EVENING. A WEAK
FRONT MOVES SOUTH ACROSS VIRGINIA OVERNIGHT INTO FRIDAY
AFTERNOON...THEN STALLS OVER NORTH CAROLINA THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
SFC HI PRES RMNS OFF THE SE CONUS CST...WHILE A WK (ILL-DEFINED)
SFC BNDRY IS DRAPED E-W INVOF MD/PA BORDER WWD INTO SRN OH VLY.
VRY WARM AIR S OF THE BNDRY W/ MNLY WSWLY WNDS (A LTL GUSTY AT
TIMES TO ABT 20 MPH). CNVTN BEGINNING TO FIRE INVOF NW VA...JUST
NNW OF CHO...W/ ONLY ISOLD PCPN FOUND TO THE ENE INTO THE INTR
PORTION FO THE LWR MD ERN SHR. CNVTN HIGH BASED (~7KFT) AND
MODIFIED SOUNDINGS ACRS NRN PORTIONS OF FA SHOWING INVERTED V IN
LWR LVLS (TO ARND 850MB). SLGT POOLING OF DEWPTS (U50S) ACRS NRN VA
SO FAR THIS AFTN. ALSO...FREEZING LVL 11.5 TO 12KFT...WILL NEED
CORES OF ANY STMS TO AOA 30KFT FOR STRONG/SVR PTNTL. LMTG FACTOR
IS DP LYRD/DOWNSLOPING W WNDS PTNTLLY MAKING IT DIFFICULT FOR STM
UPDRAFTS TO RISE SUBSTANTIALLY. MAIN THREATS - GUSTY WINDS AND
HAIL. 17Z/16 RUC GENLY HAS DECENT HANDLING ON STM DVLPMNT
ATTM...AND HV FOLLOWED FOR EVE CNVTV POPS (WHICH CONFINES STMS TO
AREAS ALG-N OF A FVX TO WAL LN). S OF THAT LN ISOLD STMS AT
BEST...BUT RIGHT NOW PROB TOO LO FOR POPS ANY HIGHER THAN 14%.
AFT EVE STMS...BNDRY SINKS S THROUGH VA AND WINDS TURN MR NLY AFT
MDNGT. LINGERING SHRAS AFT MDNGT...THOUGH POPS AOB 20% THROUGHOUT.
LO TEMPS MNLY IN THE L/M60S.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
FRNTL BNDRY SLOWLY DRIFTS S ACROSS SRN VA TONITE. ENUF SPRT TO KEEP
LOW CHC POPS...MAINLY IN THE EVE ALTHOUGH SOME SHWR ACTIVITY MAY
LINGER IVOF BNDRY AFTR MIDNITE. LOWS 60-65.
MODELS PROG FRNTL BNDRY TO STALL INVOF NRN NC LATE FRI THROUGH
SAT. MEANWHILE...SFC HIGH PRS MOVG ACROSS NEW ENGLAND LEADS TO
ONSHR WINDS. UPSHOT...AN UNSETTLED PRD XPCTD WITH SKIES VRBLY TO M
CLDY WITH PERIODIC PCPN CHCS. LOWEST POPS ACROSS ERN SHORE AND NRN
NECK AS DRYER AIR MOVES SOUTH FROM HIGH PRS TO THE NRTH. HIGHEST
POPS ACROSS WEST AND SRN AREAS CLOSER TO THE FRNT. MSTR INCRS FROM
THE WEST SAT ENHANCING PCPN CHCS ON ACROSS WRN CNTYS.
FRIDAYS TMP FCST A BIT TRICKY. ALL DEPENDS ON FRNTL LCTN AND PCPN.
HIGHS M-U70S CSTL AREAS...80-85 WEST OF BAY. LOWS FRI NITE 55-60.
HIGHS SAT L-M70S...XCPT 75-80 SRN MOST CNTYS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
A WEAK FRONTAL BOUNDARY WILL LINGER ACROSS THE MID-ATLANTIC SUNDAY.
THIS IS IN ADDITION TO A WEAK UPPER DISTURBANCE PASSING OVERHEAD
WILL PRODUCE A CHANCE FOR SHOWERS AND THUNDERSTORMS. AN H5 RIDGE
AXIS BUILDS OVER THEN EASTERN U.S. MON-WED OF NEXT WEEK. MODELS SHOW
A LOT OF UNCERTAINTY AS TO JUST HOW MUCH SHOWER/TSTM ACTIVITY WILL
OCCUR EARLY NEXT WEEK. DUE TO A LACK OF A TRIGGER TO GET ORGANIZED
TSTMS GOING...WILL LIMIT PCPN CHANCES TO THE 20-30% RANGE REACH DAY.
TEMPS WILL REMAIN ON THE WARM/MILD SIDE THROUGH THE PERIOD WITH
HIGHS IN THEN 70S AND 80S AND LOWS IN THE 60S.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
LOW PRESSURE CONTINUES TO TRACK THROUGH THE NORTHEAST TODAY AS AN
ATTENDANT COLD FRONT SLOWLY SAGS SWD INTO THE MID ATLANTIC. EXPECT
W/SW WINDS GENERALLY AROUND 10 KT WITH GUSTS UP TO 15 KT. AS THE
FRONT DROPS INTO NRN VA...ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON INTO THIS EVENING
ACROSS THE REGION...GENERALLY NORTH OF THE NC/VA BORDER. MVFR/IFR
VSBYS POSSIBLE IN THUNDERSTORMS. HOWEVER...CONFIDENCE IN TIMING
AND PLACEMENT OF ANY STORMS IS NOT HIGH ATTM...SO HAVE ONLY
INCLUDED TEMPO GROUP MENTIONING RAIN SHOWERS.
THE COLD FRONT WILL CONTINUE TO SLOWLY PROGRESS SWD...CROSSING THE
REGION LATE TONIGHT THROUGH FRIDAY. WINDS WILL BACK FROM THE W/SW
TO THE NW BEHIND THE FRONT...BUT REMAIN AOB 10 KT. SHOWERS AND
THUNDERSTORMS WILL AGAIN BE POSSIBLE FRI AFTERNOON/EVENING...MAINLY
ACROSS SRN VA/NRN NC. THE FRONT WILL STALL OVER THE CAROLINAS THIS
WEEKEND...WITH ADDITIONAL SHOWERS AND THUNDERSTORMS POSSIBLE.
&&
.MARINE...
LATEST SFC OBS SHOW SW WINDS OVER THE WATERS WITH SPEEDS GENERALLY
AROUND 15 KT. SEAS OVER THE NRN COASTAL WATERS RUNNING 3 TO 5 FT.
PRESSURE GRADIENT HAS BEGUN TO RELAX BETWEEN HIGH PRESSURE OFF THE
SE COAST AND LOW PRESSURE TRACKING ACROSS SE CANADA...BUT SPEEDS OF
25 TO 30 KT OBSERVED (KWAL SOUNDING) ABOUT 1K OFF THE SFC OF THE
WATER. PRESSURE GRADIENT WILL CONTINUE TO RELAX THROUGH THIS
MORNING...ALLOWING SPEEDS TO DIMINISH AOB 10 KT THROUGH THE
AFTERNOON. SEAS WILL ALSO FALL AOB 3 FT. WITH THAT SAID...HAVE
DROPPED SCA HEADLINES FOR THE BAY...BUT SPEEDS AROUND 15 KT WILL
CONTINUE THROUGH MID MORNING. SCA HEADLINES WILL CONTINUE FOR THE
NRN COASTAL ZONES THROUGH 7AM FOR HIGH SEAS. WINDS WILL SLOWLY BACK
TO THE W THIS AFTERNOON IN ADVANCE OF A BACKDOOR COLD FRONT. THE
COLD FRONT WILL SLOWLY PROGRESS SWD INTO NRN VA TODAY...CROSSING THE
WATER TONIGHT INTO FRIDAY. WINDS WILL BACK TO THE W/NW TO N/NE
FRIDAY...BUT REMAIN SUB SCA. THE COLD FRONT WILL STALL OVER THE
CAROLINAS THIS WEEKEND BEFORE LIFTING NWD AS A WARM FRONT THE
BEGINNING OF NEXT WEEK. E/SE WINDS LESS THAN 15 KT ARE EXPECTED OVER
THE WEEKEND.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ALB/MPR
NEAR TERM...ALB/MPR
SHORT TERM...MPR
LONG TERM...JDM
AVIATION...SAM/DAP
MARINE...JDM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
422 PM EDT THU MAY 16 2013
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 421 PM EDT THU MAY 16 2013
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW TROFFING ALONG THE W COAST
OF THE CONUS...BROAD RIDGING OVER THE CNTRL CONUS...AND A TROF
EXTENDING S INTO NEW ENGLAND. AHEAD OF THE RIDGE...IT`S BEEN A
GENERALLY SUNNY DAY ACROSS THE FCST AREA. WITH THE DRY AIR NOTED ON
THE 12Z KGRB SOUNDING...DWPTS HAVE FALLEN INTO THE 20S OVER PORTIONS
OF THE INTERIOR W HALF OF UPPER MI...RESULTING IN RH DOWN AROUND
20PCT. SFC HIGH PRES ASSOCIATED WITH APPROACHING MID LEVEL RIDGE IS
SETTLING S OVER THE UPPER GREAT LAKES AND WILL LEAD TO A QUIET NIGHT
TONIGHT. TO THE W...A COUPLE OF SHORTWAVES EMERGING OVER THE WRN
HIGH PLAINS ARE GENERATING SHRA/TSRA FROM ND TO NEBRASKA. THE SRN
WAVE OVER WRN NEBRASKA IS THE STRONGER ONE. HEADING INTO LATER
FRI...FCST WILL REVOLVE AROUND WHAT AFFECTS THESE WAVES WILL HAVE
FOR UPPER MI.
AS ALLUDED TO ABOVE...SFC HIGH PRES WILL LEAD TO A TRANQUIL NIGHT
ACROSS THE FCST AREA. MAINLY CLEAR SKIES WITH PRECIPITABLE WATER
AROUND 50PCT OF NORMAL WILL LEAD TO A QUICK TEMP DROP AFTER SUNSET.
COLUMN MOISTURE BEGINS TO INCREASE OVER THE W OVERNIGHT...AND SOME
OF THAT WILL MANIFEST ITSELF AS HIGH AND MID CLOUDS SPREADING E FROM
THE SHRA AREA CURRENTLY OVER THE DAKOTAS. IN THE END...THIS SHOULD
LEAD TO LOWEST MINS OVER THE E...THOUGH SOME OF THE TRADITIONAL COLD
SPOTS OVER THE W MAY BE EQUALLY AS LOW GIVEN THE GOOD RADIATIONAL
COOLING CONDITIONS EARLY IN THE NIGHT. GENERALLY FAVORED THE LOWER
END OF GUIDANCE ACROSS THE BOARD IN THE INTERIOR. A FEW OF THE
TYPICAL COLD SPOTS MAY SLIP JUST BLO 30F.
WHETHER ANY PCPN MAKES INTO THE FCST AREA FRI IS THE BIG QUESTION.
THE NAM IS VERY AGRESSIVE WITH PCPN...BRINGING OVER AN INCH OF RAIN
TO KIWD BY 00Z SAT WITH PCPN SPREADING AS FAR E AS SENEY. THE GFS
FOLLOWS CLOSE BEHIND THE NAM...THOUGH ITS PCPN FIELD IS DISPLACED A
LITTLE FARTHER S. THE GEM HAS NO PCPN THRU 00Z SAT...THE UKMET ONLY
BRINGS A FEW HUNDREDTHS TO SCNTRL UPPER MI...AND THE 12Z ECMWF IS
SIMILAR WITH A FEW HUNDREDTHS ALONG THE WI BORDER WHICH IS FARTHER S
AND W THAN ITS 00Z RUN. SUSPECT THE STRONGER MORE WELL-DEFINED SRN
WAVE OVER THE WRN PLAINS WILL BE THE BIGGER PLAYER...RESULTING IN
PCPN WITH THE NRN WAVE OVER ND GRADUALLY DRYING UP AS IT WILL HAVE
LIMITED/NO MOISTURE INFLOW AND IT WILL BE ENCOUNTERING DRIER AIR TO
THE E. EVEN PCPN WITH THE SRN WAVE WILL PROBABLY TEND TO DIMINISH OR
AT LEAST BE SLOWER TO ARRIVE DUE TO THE DRIER AIR OVER GREAT
LAKES...ESPECIALLY SINCE LOW-LEVEL TRAJECTORIES HAVE A GOOD EASTERLY
COMPONENT FRI THAT WILL HELP TO MAINTAIN DRY AIR OVER THE AREA. SO
PLAN WILL BE TO FAVOR THE DRIER NON NCEP MODELS FOR FRI. WHILE
RELUCTANT TO ADD PCPN CHC...WILL INCLUDE A SCHC MENTION ALONG THE WI
BORDER SINCE THE THERE WAS ONLY ONE MODEL (GEM) THAT HAD A
COMPLETELY DRY FCST. FOLLOWING THE DRIER SCENARIO...ALSO UTILIZED
LOWER DWPTS FOR FRI BY COMBINING SOME OF THE BIAS CORRECTED GUIDANCE
(GEM IN PARTICULAR) WITH DWPTS CALCULATED BASED ON MIXING HEIGHT.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 421 PM EDT THU MAY 16 2013
CONFIDENCE IS STILL RATHER LOW ON QPF POTENTIAL FRIDAY NIGHT INTO
SATURDAY ASSOCIATED WITH THE DEVELOPING BAROCLINIC ZONE. AS THE
850MB LOW OVER THE CENTRAL AND NORTHERN ROCKIES MOVES EAST...STRONG
WARM ADVECTION AND ISENTROPIC LIFT WILL SPREAD ACROSS THE UPPER
MIDWEST. THE NAM IS VERY AGGRESSIVE IN DEVELOPING SIGNIFICANT
ELEVATED CONVECTION CLOSE TO THE MI/WI BORDER LATE FRI AFTN INTO
FRIDAY NIGHT...WITH OVER 2 INCHES OF QPF FORECAST AT IMT AND IWD BY
SAT AFTN. THE 12Z GFS HAS SHIFTED THE BAROCLINIC AXIS
NORTHWARD...BUT IT IS NOT AS STRONG AS THE NAM. THE 00Z ECMWF IS
OVERALL THE WEAKEST WITH THE FRONTAL BOUNDARY BUT NONETHELESS IS
SIMILAR IN POSITION BUT A LITTLE SLOWER (SIMILAR TO WHAT THE 18Z NAM
SHOWS). THE GEM IS MUCH FURTHER SOUTH. WITH ALL THAT SAID...THE
CONSENSUS OF DETERMINISTIC AND ENSEMBLE NWP SUGGEST THAT POPS WILL
NEED TO BE RAISED ACROSS THE ENTIRE AREA (EXCEPT EAST 1/3) FRIDAY
NIGHT INTO SATURDAY. WITH THE STRONGLY CONFLUENT FLOW AND DRY AIR IN
PLACE...DO NOT EXPECT THE HEAVY PCPN PER THE NAM FORECAST...HOWEVER
SOME SHOWER ACTIVITY FRIDAY NIGHT INTO SATURDAY IS EXPECTED
ESPECIALLY CLOSER TO THE WI BORDER WHERE THE BETTER MOISTURE AND
BETTER LIFT ASSOCIATED WITH THE FRONTAL ZONE IS LOCATED.
BY SATURDAY AFTERNOON...THE BAROCLINIC ZONE SHIFTS NORTH OF THE AREA
WITH THE BEST MOISTURE TRANSPORT CLOSER TO THE LOW TO THE WEST OF
THE AREA. IN FACT...WILL LIKELY SEE SOME CLEARING LATE SAT AFTN AS
THE WARM SECTOR MOVES OVER THE AREA AND DRIER AIR ADVECTS INTO THE
AREA. WILL MAINTAIN LOW CHANCE POPS WEST SAT AFTN/NIGHT...BUT
GENERALLY DRY ELSEWHERE.
SUNDAY SHOULD END UP BEING GENERALLY DRY WITH THE BEST MOISTURE AND
LOW LVL JET TO THE WEST OF THE AREA. NAM AND GFS ARE VERY AGGRESSIVE
IN WARMING 850MB TEMPS TO +18C ACROSS THE SOUTH...BUT AM THINKING
THE MORE CONSERVATIVE ECMWF WITH 850MB TEMPS AROUND +14 SEEMS MORE
REASONABLE. REGARDLESS...SHOULD BE A NICE DAY WITH PERHAPS A CHANCE
OF SHOWERS AND THUNDERSTORMS LATE IN THE DAY SUNDAY ACROSS THE WEST.
RATHER UNSETTLED WEATHER WILL CONTINUE THROUGH THE EARLY PART OF
NEXT WEEK WITH THE UPPER LOW OVER THE NORTHERN PLAINS BEING RATHER
STUBBORN TO MOVE OUT. THIS WILL KEEP THE BAROCLINIC ZONE NEARBY
THROUGH WEDNESDAY BEFORE AN UPPER TROUGH OVER HUDSON BAY DIVES SOUTH
AND ALLOWS THE FRONT TO MOVE SOUTH OF THE AREA BY THURSDAY. WITH
THAT SAID...MON-WED LOOKS QUITE WET AT TIMES WITH SOME HEAVY RAIN
CERTAINLY POSSIBLE. ALTHOUGH 850MB TEMPS WILL BE AROUND +10C THROUGH
WED...EASTERLY FLOW DUE TO THE LOW STAYING SOUTH OF THE AREA AS WELL
AS PLENTIFUL CLOUDS WILL KEEP TEMPS COOL NEAR LAKE SUPERIOR. INLAND
TEMPS WILL LIKELY STAY NEAR NORMAL...BUT TEMPS CLOSER TO LAKE
SUPERIOR WILL BE IN THE UPPER 50S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 140 PM EDT THU MAY 16 2013
VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW THRU THIS FCST PERIOD
AS HIGH PRES MAINTAINS DRY LOW-LEVELS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 421 PM EDT THU MAY 16 2013
LIGHT WINDS WILL BE THE RULE ACROSS LAKE SUPERIOR TONIGHT WITH HIGH
PRES OVER THE UPPER LAKES. WHILE THE HIGH WILL BE SHIFTING E FRI...A
MESO HIGH MAY LINGER OVER ERN LAKE SUPERIOR THRU THE DAY. THIS WILL
KEEP WINDS LIGHT OVER THE E...BUT E TO NE WINDS WILL BEGIN TO
INCREASE OVER THE W. HEADING THRU THE WEEKEND INTO EARLY NEXT
WEEK...PRES GRADIENT OVER THE UPPER LAKES WILL SLOWLY TIGHTEN BTWN
LOW PRES SLOWLY MOVING FROM THE WRN PLAINS TOWARD THE UPPER
MISSISSIPPI VALLEY AND HIGH PRES BUILDING IN THE VCNTY OF WRN HUDSON
BAY. THIS WILL LEAD TO EASTERLY WINDS GRADUALLY INCREASING INTO
GENERALLY THE 15-25KT RANGE. COULD BE SOME PERIODS OF HIGHER WINDS
AT TIMES EARLY NEXT WEEK...ESPECIALLY OVER WRN LAKE SUPERIOR WHERE
FUNNELING/CHANNELING WILL ENHANCE THE WINDS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...MRD
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS GAYLORD MI
130 PM EDT THU MAY 16 2013
.SYNOPSIS...
ISSUED AT 353 AM EDT THU MAY 16 2013
HIGH PRESSURE WILL GRADUALLY BUILD FROM HUDSON BAY INTO NORTHERN
MICHIGAN THROUGH THE WEEKEND. THIS WEATHER PATTERN PROVIDE PLENTY OF
SUNSHINE AND WARM TEMPERATURES EACH DAY...WHILE ALSO DELIVERING
CLEAR AND CHILLY NIGHTS. OUR NEXT CHANCE FOR RAIN WILL WAIT UNTIL
EARLY NEXT WEEK...AS LOW PRESSURE TAKES SHAPE ACROSS THE WESTERN
LAKES.
&&
.UPDATE...
ISSUED AT 119 PM EDT THU MAY 16 2013
NO SIGNIFICANT CHANGES WARRANTED TO AFTERNOON FORECAST. CLOUD
COVER FAILING TO MATERIALIZE ACROSS EASTERN UPPER AS DRY AIR WINS
OUT. ELSEWHERE...CHANGES RELEGATED TO SLIGHT REAL-TIME
ADJUSTMENTS TO TEMPERATURE CURVE. ISOLATED LOCATIONS APPROACHING
RED FLAG CONDITIONS...BUT NOT WIDESPREAD ENOUGH TO WARRANT A HEADLINE.
UPDATE ISSUED AT 951 AM EDT THU MAY 16 2013
ANOTHER QUIET MORNING ACROSS THE NORTH WOODS...ALTHOUGH NOT WITHOUT
AT LEAST A FEW FORECAST CHALLENGES. BAND OF ACCAS ALONG CORRIDOR OF
IMPRESSIVE H8-H7 LAPSE RATES CONTINUES TO SPILL INTO FAR SOUTHWEST
SECTIONS OF THE AREA...AND SHOULD CONTINUE TO DO SO FOR THE NEXT
COUPLE HOURS. MUCH FURTHER NORTH...EXTENSIVE AREA OF STRATUS
CONTINUES TO SAG SOUTH AROUND BACKSIDE OF QUEBEC CENTERED LOW
PRESSURE. DIURNAL TRENDS AND DOWNSLOPING STARTING TO TAKE ITS
TOLL...WITH NOTABLE THINNING ALONG ITS SOUTHERN FLANK. STILL APPEARS
SOME OF THIS MAY SNEAK INTO EASTERN UPPER MICHIGAN...WITH ADDED
MOISTURE PERHAPS ENTICING A DIURNALLY DRIVEN STRATO-CU RESPONSE.
OTHERWISE...A DRY AND MOSTLY SUNNY DAY IS EXPECTED ACROSS THE AREA.
ONTO FIRE WEATHER CONCERNS: SECONDARY WEAK COLD FRONT HAS EXITED
SOUTH OF THE AREA...WHICH SHOULD ALLOW AFTERNOON HIGHS TO FALL JUST
SHORT OF RED FLAG CRITERIA (ESSENTIALLY...A FEW DEGREES COOLER THAN
THOSE OBSERVED YESTERDAY). WINDS AND RH VALUES...HOWEVER...EXPECTED
TO MAKE A RUN AT CRITICAL LEVELS. CORE OF GUSTY NORTHWEST WINDS (15
TO 25 MPH) EXPECTED ACROSS NORTHEAST LOWER...ESPECIALLY THROUGH
EARLY AFTERNOON. REGIONAL 12Z SOUNDING ANALYSIS AND BACKWARD
TRAJECTORY RAP GUIDANCE BOTH SUPPORT DEWPOINTS MIXING OUT INTO THE
LOWER 30S (ISOLATED UPPER 20S) THROUGH THIS AFTERNOON...PRODUCING RH
READINGS WELL BELOW 30 PERCENT ACROSS A GOOD PORTION OF INTERIOR
NORTHERN LOWER MICHIGAN. WHILE A ROGUE REG FLAG OBSERVATION OR TWO
MORE THAN EXPECTED...ESPECIALLY ACROSS THE HURON NATION FOREST
AREA...THESE SHOULD BE MORE THAN EXCEPTION THAN THE RULE...AND NOT
WORTHY OF ANY SPECIFIC HEADLINE. WILL CONTINUE TO MONITOR.
UPDATE ISSUED AT 618 AM EDT THU MAY 16 2013
NARROW LINE OF MID CLOUD PRESSING INTO NRN LOWER MICHIGAN...BUT
HAS BEEN THINNING OUT CONSIDERABLY AND NOT LIKELY TO HAVE MUCH OF
AN IMPACT ON SKY COVER THIS MORNING. TO THE NORTH...STRATUS
SLOWLY SAGGING SOUTHWARD INTO LAKE SUPERIOR WITH SHALLOW COLD
ADVECTION BEHIND THE WEAK FRONT THAT IS DROPPING THROUGH THE
REGION. NOT ENTIRELY CLEAR JUST HOW MUCH OF THE STRATUS WILL GET
INTO THE U.P. AND SUSPECT A GOOD PART WILL MIX OUT WITH DAYTIME
HEATING. BUT HAVE NUDGED UP SKY COVER (PARTLY SUNNY) FOR EASTERN
UPPER MICHIGAN LATER TODAY ACCORDINGLY.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 353 AM EDT THU MAY 16 2013
OVERVIEW: FAIRLY PROGRESSIVE FLOW PATTERN ACROSS THE CONUS WITH LOW
AMPLITUDE TROUGHINESS IN THE EASTERN GREAT LAKES INTO NEW ENGLAND
AND LOW AMPLITUDE RIDGING ADVANCING THROUGH THE PLAINS. PATTERN
EXPECTED TO AMPLIFY OVER THE NEXT SEVERAL DAYS WITH RIDGING BUILDING
THROUGH THE MIDWEST AND GREAT LAKES HEADING INTO THE WEEKEND...
SIGNALING WARMER AND RAIN-FREE DAYS AHEAD.
ON THE SMALLER SCALE...LOW PRESSURE SYSTEM IS LOCATED OVER WESTERN
QUEBEC WITH A SUBTLE FRONT CURVING BACK ACROSS THE NRN LAKES/SRN
ONTARIO REGION. FRONT IS FORECAST SAG DOWN INTO LOWER MICHIGAN TODAY
RESULTING IN SUBTLE COOLING. SO TAKE YESTERDAYS HIGHS AND TRIM OFF A
FEW DEGREES...THAT SHOULD YIELD A DECENT RESULT. NO SENSIBLE WEATHER
OCCURRING OR EXPECTED TO OCCUR WITH THE FRONT ALTHOUGH THERE IS ONE
BATCH OF MID CLOUD AND SPOTTY ELEVATED RADAR RETURNS ACROSS NRN
WISCONSIN ASSOCIATED WITH POCKET OF STEEP LOW-MID LEVEL LAPSE RATES
THAT WILL SLIDE INTO LOWER MICHIGAN TODAY. IN ADDITION...CLOUD COVER
ACROSS ONTARIO BEHIND THE FRONT MAY MAKE A RUN TOWARD EASTERN UPPER
MICHIGAN BEYOND THE FRONT THIS AFTERNOON. OVERALL...EXPECT PARTLY
CLOUDY TO MOSTLY SUNNY SKIES.
FIRE WEATHER CONCERNS...DRY ANTECEDENT CONDITIONS ALREADY IN PLACE
AND FORECAST SOUNDINGS ONCE AGAIN SUGGEST THE POTENTIAL FOR SFC
DEWPOINTS TO DROP OFF THIS AFTERNOON AFTER HEATING/MIXING TAPS VERY
DRY AIR ALOFT. LOW 30S DEWPOINTS PROBABLY EASILY ATTAINABLE...WITH
EVEN LOW VALUES POSSIBLE IF WE MIX DEEP ENOUGH. THIS WILL RESULT IN
MIN AFTERNOON RH VALUES ACROSS INLAND NRN LOWER MICHIGAN DIPPING
BELOW 25 PERCENT. HOWEVER...TEMPS WILL LARGELY REMAIN BELOW RED FLAG
CRITERIA AND WINDS TODAY WILL NOT BE NEARLY AS GUSTY AS WEDNESDAY.
NO HEADLINES...BUT WILL CONTINUE TO MENTION AN ELEVATED FIRE DANGER
THIS AFTERNOON/EVENING IN TH HAZARDOUS WEATHER OUTLOOK.
TONIGHT...MAINLY CLEAR SKIES/LIGHTER WINDS AND LOW DEWPOINTS WILL
ALLOW TEMPS TO DROP INTO THE 30S FOR MOST AREAS...WITH SOME FROST A
POSSIBILITY AS WELL. DONT EXPECT WIDESPREAD FREEZING CONDITIONS...
BUT DAY SHIFT MAY NEED TO CONSIDER FROST ADVISORY POSSIBILITIES.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 353 AM EDT THU MAY 16 2013
QUIET AND DOWNRIGHT SPECTACULAR LATE SPRING WEATHER REMAINS ON TAP
AS WE WRAP UP THE WORK WEEK AND HEAD THROUGH THE WEEKEND...WITH
REALLY NO MAJOR CONCERNS FORESEEN THROUGH SUNDAY. WHAT HAPPENS
THEREAFTER IS A BIT MORE IN QUESTION...BUT SIGNS CONTINUE TO POINT
TOWARD INCREASING PRECIPITATION CHANCES SOMETIME DURING THE FIRST
HALF OF NEXT WEEK. THE WEATHER PATTERN THROUGH THE WEEKEND IS A
QUIET ONE FOR NORTHERN MICHIGAN...FEATURING A TRANSITION FROM A
RATHER FLAT FLOW ACROSS THE NORTHERN TIER...TOWARD ONE OF AMPLIFIED
UPPER RIDGING BUILDING ACROSS THE WESTERN LAKES BY SUNDAY...
DOWNSTREAM OF RATHER SHARP TROUGH AMPLIFICATION TAKING SHAPE OVER
THE ROCKIES AND EVENTUALLY PLAINS/MISSISSIPPI VALLEY EARLY NEXT
WEEK. SAID PATTERN WILL ALSO FORCE A RATHER PRONOUNCED AREA OF MID
LEVEL CONFLUENCE ACROSS MUCH OF EASTERN CANADA WITH TIME...HELPING
DRIVE LOW LEVEL RIDGING FROM HUDSON BAY THIS WEEKEND INTO SOUTHERN
NEWFOUNDLAND BY EARLY NEXT WEEK.
LOOKING AT A FEW SPECIFICS...JUST NOT TERRIBLY EXCITED BY ANY PRECIP
CHANCES THROUGH THE WEEKEND...AS LOW LEVEL RIDGING DOMINATES WHILE
MID LEVEL HEIGHTS GRADUALLY BUILD WITH TIME. ANY MAJOR PRECIP THREAT
SHOULD BE CONFINED ACROSS THE OHIO AND MID MISSISSIPPI VALLEYS ALONG
A STALLED FRONTAL BOUNDARY (NEAR ITS CLIMO-FAVORED LOCATION THIS
TIME OF YEAR). JUST NOT BUYING INTO NAM/GFS DEPICTION OF ELEVATED
CONVECTION FIRING THIS FAR NORTH LATER FRIDAY NIGHT INTO SATURDAY...
AS THIS APPEARS TO BE TIED TO ERRONEOUS MOISTURE TRANSPORT NORTHWARD
(THIS IS A BIG PROBLEM SO FAR THIS YEAR). IN ADDITION...THE BEST
LOWER LEVEL CONVERGENCE LOOKS TO RESIDE WELL NORTHWEST OF THE AREA
ALONG AN ELEVATED WARM FRONT THROUGH WESTERN ONTARIO...WHILE A
PRONOUNCED SUB-800MB DRY WEDGE DOMINATES NORTHERN MICHIGAN. AS
SUCH...REALLY LIKE OUR CALL TO GO DRY AND WILL MAINTAIN...WITH
PERHAPS JUST A LITTLE INCREASE IN SOME MID OR HIGH CLOUDS EXPECTED.
HIGHS SHOULD WARM WELL INTO THE 60S AND 70S ONCE AGAIN...COOLEST
NEAR THE LAKESHORES WHERE LAKE BREEZE DEVELOPMENT IS LIKELY IN A
WEAK GRADIENT REGIME...ESPECIALLY FRIDAY AND SATURDAY. NIGHTS
CONTINUE TO LOOK COOL AND QUITE COMFORTABLE...AND GIVEN THE SETUP
WITH RESPECTABLE MIXING OUT OF DEW POINTS EACH AFTERNOON AND WEAK
WIND FIELDS...WILL UNDERCUT GUIDANCE NUMBERS...ESPECIALLY FRIDAY
NIGHT WITH SOME LOWER 30S POSSIBLE FOR THE USUAL COOL SPOTS ONCE
AGAIN.
THEREAFTER...CONFIDENCE CONTINUES TO BE ON THE LOW SIDE EARLY NEXT
WEEK REGARDING THE EVOLUTION OF PRECIP CHANCES ACROSS THE AREA.
LATEST GUIDANCE STILL SUGGESTING GRADUAL CLOSED LOW DEVELOPMENT OFF
TO OUR WEST ACROSS THE CENTRAL OR NORTHERN PLAINS. WHILE THE OVERALL
SPECIFICS AREN`T KNOWN JUST YET...PRECIP CHANCES WILL BE ON THE
INCREASE AS AN ELEVATED WARM FRONT EVENTUALLY WORKS NORTH THROUGH
THE AREA...FOLLOWED BY A SURFACE WARM FRONT...ALL WHILE INCREASING
DIFLUENCE ALOFT WORKS IN TANDEM WITH STRENGTHENING RETURN FLOW WITH
A WIDE OPEN GULF. IN FACT...SHOULD THINGS SET UP AS CURRENT MODELED
(THEY RARELY DO)...COULD SEE THIS BEING A HEAVY RAIN SETUP SOMEWHERE
NEARBY. OTHERWISE...TEMPS ARE QUITE TRICKY IN THIS SETUP...WITH THE
POTENTIAL FOR SOME SNEAKY VERY WARM READINGS (WELL INTO THE 80S?) AS
PRONOUNCED THERMAL RIDGING RIDES NORTH INTO THE AREA...BUT ALSO THE
CHANCE FOR RAIN-COOLED 60S PENDING THE EXACT EVOLUTION OF ANY
PRECIP. WILL CONTINUE TO SPLIT THE DIFFERENCE AT THIS POINT...BUT
WITH A NOTABLE TREND TOWARD MUCH MORE HUMID CONDITIONS TOWARD
TUESDAY AND WEDNESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 119 PM EDT THU MAY 16 2013
VFR CONDITIONS THROUGH THIS FORECAST. GUSTY NORTHWEST WINDS
QUICKLY SUBSIDE THIS EVENING...WITH LIGHT EAST FLOW EXPECTED TO
DEVELOP FRIDAY MORNING. CLEAR SKIES GIVE WAY TO INCREASING
HIGH/MID LEVEL CLOUDS LATE TONIGHT AND FRIDAY...WITH NO PRECIP
EXPECTED.
&&
.MARINE...
ISSUED AT 353 AM EDT THU MAY 16 2013
NORTHWEST WINDS WILL PREVAIL TODAY WITH SOME GUSTINESS...ALTHOUGH
GUSTS AND WAVES ARE EXPECTED TO REMAIN LARGELY BELOW SMALL CRAFT
CRITERIA. WINDS GO LIGHT TONIGHT AND REMAIN LIGHT THROUGH FRIDAY
NIGHT.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...MB
SYNOPSIS...DL
SHORT TERM...BA
LONG TERM...DL
AVIATION...MB
MARINE...BA
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
233 PM EDT THU MAY 16 2013
.SYNOPSIS...
WEAK HIGH PRESSURE WILL CONTROL OUR WEATHER THROUGH SATURDAY,
BRINGING DRY CONDITIONS AND MILD DAYTIME TEMPERATURES TO NEW YORK
AND PENNSYLVANIA.
&&
.NEAR TERM /THROUGH TONIGHT/...
1030 AM UPDATE...
FORECAST UPDATED TO LOWER DEWPOINTS FURTHER BELOW GUIDANCE
VALUES /AS WAS ALREADY BECOME EVIDENT/...AND ALSO TO KEEP UP WITH
FASTER-THAN-FORECAST WARMING THAT IS UNDERWAY. MODELS TYPICALLY
STRUGGLE WITH DEWPOINTS IN THIS SITUATION. DRY AIR FROM ALOFT
SHOULD HAVE NO PROBLEM MIXING DOWN...WITH MODEL SOUNDINGS
SUGGESTING STEEP LAPSE RATES/MIXING ALL THE WAY UP TO 700-600MB
LEVELS. AS ALREADY ACCOUNTED FOR IN FORECAST...GUSTY WINDS SHOULD
HAVE NO PROBLEM MIXING DOWN THROUGHOUT THIS AFTERNOON.
ALSO...VISIBLE SATELLITE SHOWS PLENTY OF CLOUDS CURRENTLY IN
CENTRAL TO NORTHERN ONTARIO AND MOST OF QUEBEC...BEHIND
APPROACHING SECONDARY COLD FRONT. AS DEPICTED BY 800-850MB RH
FIELDS IN RUC AND WRFARW MODELS...A BAND OF CLOUDS AT AROUND 4-5
KFT AGL SHOULD ACCOMPANY SECONDARY FRONT AS IT DROPS DOWN ACROSS
THE NORTHERN HALF OF THE AREA TONIGHT. SKY GRIDS HAVE BEEN UPDATED
ACCORDINGLY. THIS MAY HELP TO STAVE OFF PATCHY FROST THREAT IN
COLD AIR DRAINAGE PRONE VALLEYS OF THE NORTHEASTERN/EASTERN PARTS
OF THE AREA.
PREVIOUS DISCUSSION...
A SECONDARY COLD FRONT WILL DROP SOUTH OUT OF ONTARIO INTO NY LATE
TODAY. VERY DRY ATMOSPHERIC PROFILES WILL PRECLUDE ANY POSSIBILITY
FOR PRECIPITATION.
THE MAIN EFFECT OF THE FRONTAL APPROACH WILL BE TO INCREASE WINDS
DURING THE AFTERNOON HOURS. WITH HEALTHY BL-850MB WINDS PROGGED,
AND A WELL MIXED ATMOSPHERE EXPECTED, IT LOOKS LIKE A GOOD BET
FOR WIND GUSTS OF 20 TO 25 MPH THIS AFTERNOON.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
UL RIDGE BUILDS THROUGH THE OHIO VALLEY AND GREAT LAKES THIS
PERIOD. ATMOSPHERIC MOISTURE WILL REMAIN LOW OVER THE NORTHEASTERN
U.S. THROUGH SATURDAY NIGHT, WITH SLIGHTLY BELOW NORMAL 850MB
TEMPS OVERHEAD.
THE RESULT WILL BE A FAIR WEATHER PERIOD, WITH MILD SUNNY DAYS AND
COOL NIGHTS. CANNOT RULE OUT SOME UPPER 30S MINS TONIGHT AND
POSSIBLY FRIDAY NIGHT, ESPECIALLY IN THE SHELTERED VALLEYS OVER
THE EASTERN FA.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
MEDIUM RANGE MODELS ARE IN FAIR AGREEMENT THROUGH THIS PERIOD
INDICATING AN UPPER LEVEL RIDGE WILL BUILD OVER THE NORTHEAST
INITIALLY AS AN UPPER LEVEL TROF DIGS INTO THE NORTHERN PLAINS.
TOWARD THE END OF THE PERIOD THE RIDGE WILL FLATTEN THEN AN UPPER
LEVEL TROF DROPPING THROUGH EASTERN CANADA WILL MOVE INTO THE
NORTHEAST.
AT THE SFC, SUNDAY NIGHT INTO MONDAY, HIGH PRES OFF THE NEW
ENGLAND COAST AND A WARM FRONT DRAPED OVER THE MID ATLANTIC WILL
PROVIDE A SOMEWHAT MOIST RETURN FLOW BRINGING PRIMARILY A SLIGHT
CHC FOR SHOWERS OVER CENTRAL NY AND CHC FOR NE PA.
FOR THE REMAINDER OF THE PERIOD WILL CONTINUE TO CARRY CHC POPS
FOR SHOWERS AND THUNDERSTORMS, AS SFC LOW PRES MOVING INTO THE
WESTERN LAKES WILL BRING A WARM FRONT TO THE VCNTY THROUGH
TUESDAY NIGHT WITH THE TRAILING COLD FRONT MOVING THROUGH WED/WED
NIGHT. WILL ADVERTISE CHC/SLIGHT CHC POPS ON THURSDAY, POST FRONTAL
AS UPPER LEVEL TROF RESIDES OVER REGION.
TEMPS THROUGH THE PERIOD WILL RUN 5-10 DEGREES ABOVE NORMAL WITH A
RETURN TO MORE SEASONAL TEMPS BY THURSDAY.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
VFR CONDITIONS WILL CONTINUE THROUGH THIS TAF PERIOD. SCATTERED
MID LEVEL CLOUDS WILL CLEAR BY EARLY EVENING BEFORE A SECONDARY
TROF DROPS THROUGH OVERNIGHT. THIS FEATURE WILL PRODUCE SCT/BKN
CLOUDS AROUND 4K FT. ON FRIDAY, JUST SCATTERED CU WILL PERSIST.
NORTHWEST WINDS AT 10-12 KNOTS GUSTING TO 25 KNOTS THEN
DECREASING TO 5 KNOTS THIS EVENING. NORTHWEST WINDS AROUND 10
KNOTS ON FRIDAY.
OUTLOOK...
FRI NIGHT THROUGH TUESDAY...PRIMARILY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJP
NEAR TERM...DJP/MDP
SHORT TERM...DJP
LONG TERM...RRM
AVIATION...RRM
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
331 PM CDT THU MAY 16 2013
.VERY SHORT TERM...TONIGHT AND FRIDAY. FORECAST CONFIDENCE...
MEDIUM
A SLIGHT CHANCE FOR SHOWERS ACROSS THE NORTHWEST FORECAST AREA WAS
HELD ONTO THROUGH EARLY EVENING. CURRENTLY...THERE IS A LOT OF
CUMULUS DEVELOPMENT IN THE NORTHEAST...BUT NO SIGNS OF
PRECIPITATION. MAY HAVE TO REMOVE THESE POPS BY LATE AFTERNOON IF
LACK OF DEVELOPMENT PERSISTS. MODELS HAVE BACKED OFF AS WELL...SO
LOOKING LESS LIKELY BY THE HOUR. DEW POINT DEPRESSIONS ARE ON THE
ORDER OF 40 DEGREES AT THE MOMENT ACROSS THE NORTHWEST...SO THE DRY
AIR IS LIKELY CONTRIBUTING TO THE LACK OF DEVELOPMENT.
SHOULD BE DRY THEN THROUGH THE MAJORITY OF THE NIGHT. THE HRRR TRIES
TO SNEAK SOME ACTIVITY INTO THE SW A BIT EARLIER THAN OTHER
MODELS...BUT GENERALLY HELD OFF ON POPS UNTIL EARLY TOMORROW
MORNING. AS THE LAKE AIR MASS CONTINUES TO PUSH INLAND UNDER EASTERLY
WINDS...LOWS TONIGHT SHOULD NEAR NORMAL VALUES...MAINLY IN THE UPPER
40S TO LOW 50S.
WILL HAVE A BAROCLINIC ZONE STRETCHED NORTHWEST TO SOUTHEAST ACROSS
THE FORECAST AREA ON FRIDAY...WHILE A WEAK SHORTWAVE APPROACHES THE
AREA. THESE FEATURES WILL LIKELY COMBINE TO KICK OFF SHOWER AND
THUNDERSTORM ACTIVITY TOMORROW...PARTICULARLY ACROSS THE WEST AND
SOUTHWEST TOWARD THE MILDER AIR. A COOL AND STABLE AIR MASS OFF THE
LAKE WILL LIKE INHIBIT DEVELOPMENT IN THE EAST...SO KEPT POPS LOW.
WILL SEE GOOD SPREAD IN HIGH TEMPS TOMORROW...WITH HIGHS LIKELY NOT
GETTING OUT OF THE 50S ALONG THE LAKESHORE UNDER ONSHORE WINDS...TO
THE LOW 70S IN THE SOUTHWEST.
.SHORT TERM...FRIDAY NIGHT THROUGH SUNDAY.
FRIDAY NIGHT...FORECAST CONFIDENCE
MODELS TAKE PRECIPITATION MAXIMA AT THE START OF THE PERIOD TO THE
NORTH AND SOUTH OF THE FORECAST AREA WITH DEPARTING SHORT WAVES.
LINGERING Q-VECTOR CONVERGENCE SUPPORT A GRADIENT OF CHANCE
POPS...WITH THE HIGHER CHANCES NORTH...DIMINISHING AFTER 06Z
SATURDAY. WITH WARM FRONT JUST PUSHING INTO THE FAR SW...WILL SEE A
NEARLY 10-DEGREE DIFFERENCE WITH OVERNIGHT LOWS...WITH UPPER 40S IN
THE NORTHEAST AND UPPER 50S IN THE FAR SW.
SATURDAY...FORECAST CONFIDENCE MEDIUM.
ENOUGH INSTABILITY AS DAYTIME HEATING/MIXING KICK IN...AND LOW-LEVEL
CONVERGENCE AS WARM FRONT STALLS AND BECOMES A STATIONARY FRONT
THROUGH THE MIDDLE PORTIONS OF THE CWA...TO WARRANT LOW-END POPS.
SOME OF THE HIGHER INSTABILITY IS PREDICATED ON HIGHER THAN
EXPECTED MODEL SURFACE DEW POINTS...A RECENT PROBLEM ON THE
MODELS...SO HOLDING TO ONLY SLIGHT CHANCE POPS APPEARS
APPROPRIATE. WILL SEE A STRONG TEMPERATURE CONTRAST ACROSS THE
STATIONARY BOUNDARY WITH MID-UPPER 70S IN THE SW 1/2....AND UPPER
60S TO LOW 70S NE HALF.
SATURDAY NIGHT...FORECAST CONFIDENCE HIGH.
RIDGING AHEAD OF DEEPENING WAVE KEEPS AREA DRY. EASTERLY WINDS BRING
UPPER 40S-LOW 50S ALONG THE KETTLE MORAINE AND EAST...AND IN THE MID
TO UPPER 50S TO THE WEST WITH LOW 60S IN THE SOUTHWEST.
.LONG TERM...
THIS PERIOD DOMINATED BY IMPACT OF CLOSED...NEARLY-STACKED LOW AS IT
MOVES/FILLS OVER THE UPPER MIDWEST. CHANCES FOR THUNDER EACH PERIOD
FROM SUNDAY NIGHT INTO WEDNESDAY WITH LOBES OF VORTICITY ROTATING
AROUND CENTRAL CIRCULATION PROVIDING LIFT TO A WARM...MOIST UNSTABLE
AIR MASS FEEDING INTO THE REGION ON SRLY FLOW AHEAD OF TROUGH. CIPS
ANALOGS HAS INCREASING PROBABILITIES MOVING INTO SW WI MONDAY/MONDAY
NIGHT...WITH SPC DAY 4-8 COMPOSITE OUTLOOK BRUSHING SOUTHWEST
WISCONSIN ON DAYS 4 AND 5.
SOME QUESTION AS TO EVOLUTION OF SYSTEM...12Z ECMWF SLOWLY OPENS
THE SYSTEM AND MOVES IT SOUTHEAST AS IT PHASES WITH A SHORT WAVE
DROPPING THROUGH EASTERN ONTARIO/WESTERN QUEBEC...WHILE THE GFS
HAS THE LOW FILL AND SHEAR OUT OVER THE WESTERN GREAT LAKES.
EITHER SOLUTION KEEPS THE MAJORITY OF THE EXTENDED WITH PCPN
CHANCES UNTIL THE REMNANT LOW/TROUGH DROPS SOUTHEAST BY
THURSDAY/THURSDAY NIGHT. SHOULD SEE MODE CHANGE FROM THUNDER TO
RAIN SHOWERS WEDNESDAY NIGHT AND THURSDAY AS MID-LEVEL OCCLUSION
PUSHES THE MORE UNSTABLE AIR MASS TO THE EAST.
&&
.AVIATION/00Z TAFS/...
VFR CONDITIONS WILL PERSIST THROUGH FRIDAY. SHOULD SEE MAINLY DRY
WEATHER THIS EVENING AND OVERNIGHT. THERE WILL BE A CHANCE FOR
SHOWERS AND STORMS FRIDAY...THE BEST CHANCE IN THE LATE MORNING AND
AFTERNOON WEST OF A FOND DU LAC TO JANESVILLE LINE.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TONIGHT/FRIDAY AND AVIATION/MARINE...DDV
FRIDAY NIGHT THROUGH THURSDAY...REM