Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 05/29/13
AREA FORECAST DISCUSSION
NWS RENO NV
930 AM PDT MON MAY 27 2013
.SYNOPSIS...
LOW PRESSURE OVER THE WESTERN U.S. WILL SPREAD RAIN ACROSS NORTHEAST
CALIFORNIA AND NORTHWEST NEVADA TODAY AND TONIGHT, WITH SCATTERED
SHOWERS DEVELOPING LATER TODAY ACROSS THE REMAINDER OF THE REGION
MAINLY NORTH OF HIGHWAY 50. ANOTHER ROUND OF LIGHTER RAIN SHOWERS
IS POSSIBLE BY LATE TUESDAY NIGHT NORTH OF INTERSTATE 80. BREEZY
CONDITIONS ARE EXPECTED THROUGH MIDWEEK, FOLLOWED BY DRY WEATHER
WITH A WARMING TREND LATER IN THE WEEK.
&&
.MORNING UPDATE...
BASED ON RADAR TRENDS AND LATEST HRRR HIGH RESOLUTION GUIDANCE WILL
INCREASE POPS IN THE SIERRA ZONES FROM TAHOE NORTH. DECENT BAND OF
SHOWERS SPILLING OVER INTO AREAS EAST OF SUSANVILLE TOO. NO OTHER
CHANGES TO THE DAY 1 FORECAST. LOOKING AT NEW 12Z GUIDANCE, MODELS
ARE SHOWING BROAD AREA OF PRECIP DEVELOPING OVERNIGHT IN RESPONSE TO
JET STREAK AND INSTABILITY. WILL LIKELY BE INCREASING POPS FOR NV
ZONES TONIGHT WITH THE AFTERNOON PACKAGE.
CS
&&
.SHORT TERM...
RAIN IS CURRENTLY SPREADING EAST ACROSS NORTHWEST CALIFORNIA AND
SOUTHERN OREGON AS UPPER LEVEL TROUGH AND PLUME OF DEEPER MOISTURE
REACHES THESE AREAS. THIS RAIN WILL CONTINUE ADVANCING EAST THIS
MORNING AND MAINLY OCCUR IN AREAS FROM SUSANVILLE-GERLACH
NORTHWARD FOR MUCH OF THE DAY AND INTO TONIGHT, WITH RAINFALL
TOTALS OF 0.25 TO 0.50 INCH LIKELY. FARTHER SOUTH THE
PRECIPITATION AMOUNTS WILL DROP OFF IN MOST AREAS AS THE LATEST
GUIDANCE HAS GENERALLY SHIFTED THE STORM TRACK FARTHER NORTH
COMPARED TO PREVIOUS MODEL RUNS.
UPPER LEVEL FORCING AND INCREASING INSTABILITY IS PROJECTED TO
ARRIVE BY LATE AFTERNOON, WITH THUNDERSTORMS POSSIBLE ACROSS THE
WEST CENTRAL NV BASIN AND PARTS OF NORTHWEST NV AFTER 5 PM AND
CONTINUING THROUGH THE EVENING. THE LATEST GUIDANCE KEEPS SOME
UPPER LEVEL DYNAMICS OVER EASTERN PERSHING/CHURCHILL COUNTIES
OVERNIGHT, SO SHOWERS COULD CONTINUE REDEVELOPING IN THESE AREAS
INTO EARLY TUESDAY MORNING.
FOR THE RENO-TAHOE AREA SOUTH INTO MONO-MINERAL COUNTIES, THE
PRECIPITATION IS LOOKING LESS IMPRESSIVE AS THE DEEP MOISTURE
PLUME BECOMES THINNER AND MORE FRAGMENTED AS IT MOVES SOUTH ALONG
THE CA COAST. EXCEPT FOR AREAS NEAR THE SIERRA CREST, SHADOWING
LOOKS MORE LIKELY TO LIMIT RAINFALL AMOUNTS TO LESS THAN 0.10 INCH
ACROSS THE MAJORITY OF WESTERN NV INCLUDING THE RENO-CARSON
VICINITY. THE HIGH ELEVATION SNOW POTENTIAL IS ALSO REDUCED
ESPECIALLY SOUTH OF TAHOE, WITH MAYBE AN INCH OR SO ABOVE 8500
FEET NEAR THE SIERRA CREST, PRODUCING ONLY MINIMAL IMPACTS ON
TRAVEL OVER THE HIGHER MOUNTAIN PASSES TONIGHT. ON THE MORE
HEAVILY TRAVELED ROUTES ACROSS THE SIERRA SUCH AS I-80 AND HIGHWAY
50, ROADS SHOULD JUST BE WET TONIGHT.
ANOTHER DAY OF BREEZY WEST WINDS IS EXPECTED, WITH WINDS
INCREASING BY LATE MORNING IN THE TAHOE BASIN AND BY EARLY
AFTERNOON FOR WESTERN NV SOUTHWARD TO MONO COUNTY. HOWEVER, THE
PRESENCE OF WIDESPREAD CLOUD COVER WILL RESULT IN STRONGER RIDGE
WINDS DEVELOPING LATER TODAY HAVING MORE DIFFICULTY MIXING DOWN TO
LOWER ELEVATIONS. OCCASIONAL GUSTS NEAR OR SLIGHTLY ABOVE 30 MPH
WILL STILL BE POSSIBLE AROUND RENO-CARSON AND IN AREAS SOUTH OF
HIGHWAY 50, BUT THESE GUSTS ARE LIKELY TO COVER A SHORTER DURATION
AND BE MORE LOCALIZED COMPARED TO THE PAST FEW DAYS. LOCALLY CHOPPY
CONDITIONS CAN BE EXPECTED ON SOME LAKES TODAY, BUT WIND SPEEDS
AND WAVE HEIGHTS ARE LESS LIKELY TO REACH CRITERIA FOR LAKE WIND
ADVISORIES DUE TO THE EXPECTED CLOUD COVER AND LESS EFFICIENT
MIXING.
PRECIP SHOULD TAPER OFF ON TUESDAY WITH A DRIER NORTHWEST FLOW
PREVAILING. WINDS AGAIN WILL NEED TO BE WATCHED WITH POTENTIAL
GUSTS NEAR 30 MPH. ANOTHER WEAKER SHORTWAVE MOVING INTO THE
NORTHWEST U.S. COULD BRING SOME LIGHT RAIN SHOWERS MAINLY IN
NORTHEAST CA-NORTHWEST NV LATE TUESDAY NIGHT INTO WEDNESDAY
MORNING. THE NAM BRINGS SOME LIGHT RAIN AS FAR SOUTH AS THE
SIERRA WEST OF TAHOE AND INTO MUCH OF PERSHING COUNTY, WHILE THE
ECMWF/GFS CONFINE MOST OF THE RAIN TO AREAS NORTH OF SUSANVILLE-
GERLACH WITH THIS SYSTEM, WHILE WINDS INCREASE YET AGAIN FROM I-80
SOUTHWARD. MJD
.LONG TERM...THURSDAY THROUGH SUNDAY...
UNLIKE PREVIOUS DAYS THE MEDIUM RANGE MODELS ARE NOW ALL IN GENERAL
AGREEMENT WITH MAJOR FEATURES THROUGH THE BULK OF THE EXTENDED
FORECAST. THE OPERATIONAL MODELS START TO BUILD A MID/UPPER LVL
RIDGE WEST OF THE FORECAST AREA THURSDAY WHILE A WEAK SFC BOUNDARY
DROPS SOUTH ACROSS THE REGION LATE THURSDAY INTO FRIDAY MORNING.
THIS COULD RESULT IN INCREASED WINDS OVER THE SIERRA THURSDAY NIGHT
AS THE THERMAL/PRESSURE GRADIENT STRENGTHENS AND PRODUCE CHOPPY
CONDITIONS THURSDAY NIGHT/FRIDAY MORNING ON LAKE TAHOE.
A FEW GEFS ENSEMBLE MEMBERS DO NOT BUILD THE RIDGE QUITE AS
MUCH...BUT THE OVERALL CONSENSUS IS RIDGING THROUGH AT LEAST EARLY
SATURDAY. THIS WILL MEAN INCREASING TEMPS FRIDAY INTO THE WEEKEND
WITH LOWER HUMIDITY FOR THE MID SLOPES AND RIDGES BY LATE FRIDAY.
MODELS ARE ALSO IN GOOD AGREEMENT THAT THE RIDGE WILL BEGIN TO
FLATTEN BY LATE SATURDAY INTO SUNDAY..BUT THERE ARE DIFFERENCES IN
THE DETAILS BY SUNDAY REGARDING HOW MUCH THE RIDGE WILL FLATTEN. THE
GFS IS A LITTLE MORE AGGRESSIVE THAN THE ECMWF...BUT THE GEFS
ENSEMBLE MEMBERS SHOW ENOUGH SPREAD TO PRECLUDE GOING WITH THE
STRAIGHT GFS SOLUTION. HIGH TEMPERATURE GUIDANCE FROM THE OPERATIONAL
GFS IS NEAR THE HIGH END OF THE ENSEMBLE GUIDANCE...SO KEPT TEMPS A
LITTLE UNDER THIS GUIDANCE. THE ECMWF GUIDANCE IS A LITTLE
HIGHER...HINTING AT 90S FOR THE WESTERN NV BASINS BY SUNDAY.
A WEAK TROUGH BEGINS TO DROP INTO THE WEST COAST LATE SUNDAY...BUT
SHOULD NOT PRODUCE ENOUGH INSTABILITY FOR THUNDER OVER OUR AREA.
MODELS ARE SHOWING ENOUGH LOW LVL THERMAL GRADIENT TO BEGIN
INCREASING THE WINDS FOR SUNDAY. THEN BEYOND THE EXTENDED PERIOD
MONDAY LOOKS LIKE IT COULD BE A BREEZY DAY AS WELL AS THE PRESSURE
GRADIENT BEGINS TO INCREASE. 20
&&
.AVIATION...
AS LOW PRESSURE PUSHES ACROSS NRN CA THIS MORNING/AFTERNOON...PCPN
WILL BEGIN TO SPREAD INTO THE NRN PORTIONS OF THE FORECAST AREA. THE
BEST CHANCES FOR PCPN WILL REMAIN NORTH OF I-80 THIS AFTERNOON THEN
SPREAD INTO THE BASIN OVERNIGHT. WITH INCREASING MSTR AND BETTER
CHANCES FOR PCPN LATE THIS AFTERNOON AND THIS EVENING THINK CIGS
WILL BEGIN TO LOWER FOR ALL AREAS EXCEPT AREAS SOUTH OF MONO LAKE TO
HAWTHORNE. MVFR CONDITIONS ARE LIKELY IN THE NRN SIERRA...NORTHEAST
CA AND FAR NW NV THIS AFTERNOON AND EVENING DUE TO LOWERED CIGS.
WHILE WINDS WILL INCREASE ALOFT TODAY...MUCH OF THIS WIND WILL NOT
MIX TO THE SFC DUE TO INCREASED MSTR. MOST SFC WINDS GUSTS WILL BE
25 KTS OR LESS...BUT THERE COULD BE A FEW GUSTS CLOSER TO 30 KTS
NEAR KMMH AND KHTH LATER THIS AFTERNOON.
PCPN DECREASES IN AREAL COVERAGE BY MIDDAY TUESDAY WITH A RETURN TO
VFR CONDITIONS ALL AREAS AND LIGHTER WINDS. 20
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
950 PM PDT SUN MAY 26 2013
.SHORT TERM DISCUSSION...
AREA OF ENHANCED CLOUDS ALONG THE ORE/NRN CA COAST AHEAD OF UPPER
TROF ALONG 130W WILL BE PUSHING INLAND TONIGHT. HRRR PRECIP FORECAST
INDICATES LEADING EDGE OF THE RAIN WILL BE NEARING THE BURNEY...RED
BLUFF...STONEYFORD LINE BY AROUND 13Z MON...SO RDD AND RBL MAY HAVE
SOME LIGHT PRECIP EARLY MON MORNING. LEADING EDGE OF PRECIP THEN
FORECAST TO MOVE INTO THE I-80 CORRIDOR BY LATE MORNING...18Z OR
SO...ESPECIALLY OVER THE W SLOPE SIERNEV BUT NOT NECESSARILY IN THE
SRN SAC VLY AS THE PRECIP IS A LITTLE MORE PROBLEMATIC THERE...AND
MAY HOLD OFF UNTIL THE 00Z-06Z TUE TIME FRAME PER THE GFS VALLEY
CROSS SECTION WHEN MOISTURE AND UPWARD MOTION ARE COINCIDENT. HIGH
PWS OFF THE COAST ARE SPLITTING AS THE UPPER JET DRIVES SEWD ACROSS
THE REGION. SO THE DEEPER MOISTURE IS LIKELY TO BE N OF THE I-80
CORRIDOR.
STRATUS SCHEME HAS COME OUT NEGATIVE THIS EVENING...BUT ONSHORE
GRADS AND ONSHORE FLOW THROUGH THE DELTA MAY ALLOW FOR ANOTHER
MORNING OF STRATUS ON THE E SIDE OF THE VALLEY SIMILAR TO SUN
MORNING...AND ALSO SOMEWHAT SUGGESTED BY THE NAM BUFKIT MOISTURE
PROFILES FOR SAC AREA SITES. JHM
.PREVIOUS DISCUSSION...
SOME LINGERING CHANCES OF SHOWERS WILL PERSIST ON TUESDAY AND
MAINLY FOR THE WESTERN SLOPES...BUT FOR THE MOST PART THE SYSTEM
WILL HAVE PASSED THROUGH THE REGION WITH ONLY SOME RESIDUAL
SHOWERS IN ITS WAKE REMAINING. NOT A LOT OF RAIN IS EXPECTED FROM
THIS SYSTEM WITHIN THE VALLEY WITH AMOUNTS RANGING FROM TRACE
TO TWO TENTH OF AN INCH...WHILE THE MOUNTAINS SHOULD FAIR A
LITTLE BETTER WITH AMOUNTS RANGING FROM TWO TENTHS TO THREE
QUARTERS OF AN INCH OF RAIN. SOME LIGHT SNOW ACCUMULATIONS WILL BE
POSSIBLE MONDAY NIGHT ABOVE 8000 FEET.
ON WEDNESDAY ANOTHER SHORTWAVE WILL MOVE INTO THE PACIFIC
NORTHWEST WITH THE TAIL END PUSHING THROUGH NORTHERN CALIFORNIA.
THIS WILL BRING CONTINUED SHOWER CHANCES TO THE MOUNTAINS...MAINLY
NORTH OF I-80 AND OVER THE NORTHERN SACRAMENTO VALLEY.
TEMPERATURES WILL CONTINUE TO BE COOLER THAN NORMAL.
.EXTENDED DISCUSSION (THURSDAY THROUGH SUNDAY)
UNSETTLED WEATHER LINGERS OVER HIGHER TERRAIN ON THURSDAY AS OUR
REGION IS SANDWICHED BETWEEN A TROUGH TO THE NORTHEAST AND HIGH
PRESSURE TO THE SOUTHWEST. PRECIPITATION WILL TAPER OFF DURING
THE DAY ON THURSDAY AND DRY WEATHER WILL PERSIST THROUGH THE WEEKEND.
TEMPERATURES ON THURS WILL BE NEAR TO 5 DEGREES BELOW NORMAL BUT
THE REGION WILL UNDERGO A WARMING TREND INTO THE WEEKEND.
TEMPERATURES IN THE UPPER 80S TO LOW 90S FOR THE VALLEY ON FRIDAY
THRU SUNDAY WHILE THE MOUNTAINS WARM INTO THE UPPER 60S AND 70S.
JBB
&&
.AVIATION...
VFR CONDITIONS UNTIL 12Z-18Z MON WHEN CIGS/VSBYS MAY LOWER TO MVFR
DUE TO -RASH/RASH OVER NRN SAC VLY INCLUDING NRN MTNS...SPREADING
SEWD TOWARDS I-80 CORRIDOR FROM 18Z-00Z TUE. OVER MTNS...CIGS/VSBYS
LOWERING TO IFR IN SHRA OBSCG HYR TRRN THROUGHOUT THE DAY. CENTRAL
AND SRN SAC/NRN SJ VLY EXPECTED TO MAINTAIN VFR CONDITIONS ALTHO SCT
-SHRA POSSIBLE ESPECIALLY N OF THE I-80 CORRIDOR AFT 18Z MON.
POSSIBLE MFR CIGS BETWEEN 12Z-18Z MON FOR SRN SAC VLY/NRN SJ VLY AND
SIERNEV FOOTHILLS DUE TO MORNING STRATUS.
&&
.STO WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS ALBANY NY
953 PM EDT TUE MAY 28 2013
.SYNOPSIS...
A WARM FRONT WILL APPROACH THE REGION FROM THE SOUTHWEST
TONIGHT... AND MOVE THROUGH THE REGION EARLY WEDNESDAY. MUCH
WARMER TEMPERATURES ARE EXPECTED FOR THE REMAINDER OF THE WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
AS OF 945 PM EDT...CURRENT FORECAST LOOKS TO BE ON TRACK WITH ONLY
MINOR UPDATES TO THE GRIDS. SHOWERS AND THUNDERSTORMS HAVE ENTERED
WESTERN NEW YORK AND CONTINUE TO MOVE EAST/SOUTHEAST WITH TIME.
REGIONAL RADAR MOSAIC AND LOCAL SURROUNDING RADARS DEPICT SEVERAL
CONVECTIVE ELEMENTS PRESENT WITHIN THE HEAVIER
SHOWERS...SUGGESTING THERE IS SUFFICIENT ELEVATED INSTABILITY FOR
EMBEDDED THUNDERSTORMS. RESIDUAL SURFACE-BASED INSTABILITY HAS
EVEN RESULTED IN A COUPLE OF SEVERE THUNDERSTORMS ALONG THE
SOUTHERN FLANK ACROSS THE WESTERN NY/PA BORDER...HOWEVER THESE
STORMS WILL TRACK WELL SOUTH OF THE FORECAST AREA.
PREV DISCUSSION BELOW...
MEANWHILE...A CLUSTER OF THUNDERSTORMS CONTINUES TO MOVE
EAST/SOUTHEAST FROM THE GREAT LAKES REGION. CURRENT THINKING IS THAT
THIS BATCH OF SHOWERS/THUNDERSTORMS WILL IMPACT THE FORECAST AREA
AFTER 03Z. THE QUESTION REMAINS TO WHAT EXTENT PRECIPITATION
COVERAGE WILL BE THIS EVENING/TONIGHT...AS LATEST HRRR RUNS INDICATE
THE HEAVIEST QPF FALLING SOUTH OF THE FORECAST AREA WHILE OTHER
MESOSCALE MODELS AND THE NAM/GFS CAMP INDICATE A MORE NORTHERN
TRACK. HAVE ADJUSTED POPS SIGNIFICANTLY DOWNWARD TO ACCOUNT FOR
UNCERTAINTY BUT HAVE GENERALLY INDICATED CHANCE POPS THROUGH THE
EVENING HOURS...AND INCREASING TO LIKELY AFTER MIDNIGHT AS SOME
BETTER OVERRUNNING LIFT/ELEVATED INSTABILITY SHOULD ALLOW FOR AN
INCREASE IN SHOWER/THUNDERSTORM COVERAGE ACROSS THE FORECAST AREA.
RAINFALL AMOUNTS SHOULD GENERALLY BE BETWEEN A TENTH AND QUARTER
OF AN INCH.
LOWS TONIGHT WILL SETTLE IN THE UPPER 40S/LOWER 50S IN PORTIONS OF
THE ADIRONDACKS TO MID/UPPER 50S ACROSS THE MID HUDSON VALLEY.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY/...
OUR REGION WILL BE SITUATED ON THE NORTHERN FRINGE OF A BUILDING
RIDGE ACROSS THE EASTERN CONUS ON WEDNESDAY. AT THE SFC...WE WILL
BE POKING INTO THE WARM SECTOR AS THE WARM FRONT WILL BE LIFTING
ACROSS THE REGION. THE WARM FRONT WILL BE MOVING ACROSS THE THE
REGION WEDNESDAY MORNING...SO HAVE CONTINUED LIKELY POPS FOR A FEW
HOURS...ESPECIALLY ACROSS THE NORTH.
AFTERWARD...SOME BREAKS OF SUN WILL OCCUR...ESP FOR VALLEY AREAS.
A SHORTWAVE WILL BE MOVING WITHIN THE STRONG W-SW FLOW ALOFT
ACROSS ONTARIO TOWARDS NORTHERN NY FOR THE AFTN HOURS. THE AMOUNT OF
SUNSHINE THAT OCCURS WILL BE CRITICAL...AS THIS WILL DETERMINE JUST
HOW MUCH INSTABILITY CAN BUILD UP. MODELS SHOW SHEAR VALUES BETWEEN
30 AND 40 KTS...AND CAPE VALUES OF 500-1500 J/KG. SPC CONTINUES TO
HAS PLACE OUR REGION IN A SLIGHT RISK FOR SEVERE WX AND HAS EVEN
EXPANDED THE SIZE OF THE AREA...AND IT APPEARS THAT WE WILL HAVE
SEVERAL INGREDIENTS IN PLACE FOR SOME GUSTY TSTMS.
HAVE 40 TO 50 PERCENT FOR SHOWERS/TSTMS. HAVE TRENDED MAX TEMPS
TOWARDS THE WARMER MAV GUIDANCE WITH HIGHS IN THE MID 70S TO MID
80S.
THE CHANCE FOR TSTMS WILL BE DECREASING TO ONLY SLIGHT CHANCE LATE
WEDNESDAY NIGHT AS THE SHORTWAVE MOVES EASTWARD...AND SFC HEATING
DIMINISHES. LOWS WILL BE IN THE MID 50S TO MID 60S.
850 HPA WILL RISE TO 16-18 DEGREES C ON THURSDAY...WITH THE 500 HPA
RIDGE CENTERED OVER THE DELMARVA. IT WILL BE WARM AND MUGGY...WITH
MAX TEMPS IN THE UPPER TO LOWER 90S. THE SFC BOUNDARY SHOULD BE
LOCATED FAR ENOUGH TO NORTH OF THE AREA FOR LITTLE LARGE SCALE
FORCING TO BE IN PLACE ACROSS OUR AREA...SO WIDESPREAD CONVECTION IS
NOT ANTICIPATED. MOST AREAS WILL LIKELY BE CAPPED AS WELL. HAVE
ONLY FORECAST A SLIGHT CHANCE OF TSTMS DURING THE AFTERNOON.
WITH THE RIDGE AND STRONG CAP STILL OVER THE REGION THURSDAY
NIGHT...HAVE NOT FORECAST ANY PCPN. IT WILL REMAIN WARM AND MUGGY
WITH LOWS IN THE UPPER 50S TO MID 60S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
THE LONG TERM WILL BE CHARACTERIZED BY INCREASING TEMPERATURES AND
HUMIDITY ALONG WITH CHANCES FOR SHOWERS AND THUNDERSTORMS AS A COLD
FRONT CROSSES THE REGION DURING THE WEEKEND.
LONG RANGE GUIDANCE CONTINUES TO BE IN EXCELLENT AGREEMENT HANDLING
MUCH OF THE LONG TERM PERIOD WITH BOTH THE 12Z GFS/ECMWF AND VARIOUS
ENSEMBLE MEMBERS DEPICTING A LARGE WARM CORE HIGH ACROSS THE EASTERN
THIRD OF THE NATION. THIS SYNOPTIC SETUP WILL BE PREVALENT THROUGH
MUCH OF THE FIRST WEEKEND OF JUNE...ALLOWING FOR A PERSISTENT
SOUTHWESTERLY RETURN FLOW TRANSPORT OF WARM AND HUMID AIR ACROSS THE
REGION AS MANY LOCATIONS ACROSS THE FORECAST AREA LOOK TO REACH 90
DEGREES FOR THE FIRST TIME IN 2013 ON FRIDAY.
A PATTERN SHIFT WILL START TO SLOWLY TAKE PLACE BEGINNING
SATURDAY...AS AN UPPER-LEVEL TROUGH AND ASSOCIATED SURFACE LOW
PRESSURE SYSTEM AND COLD FRONT APPROACH FROM THE UPPER MIDWEST. WITH
THE LARGE ANTICYCLONIC BERMUDA CIRCULATION FIRMLY ENTRENCHED ACROSS
THE EASTERN CONUS AND A POSITIVE-TILT ORIENTATION TO THE UPSTREAM
TROUGH...THERE REMAINS SOME UNCERTAINTY REGARDING THE EXACT TIMING
OF THE COLD FRONTAL PASSAGE ACROSS THE FORECAST AREA.
REGARDLESS...HAVE INTRODUCED SLIGHT CHANCE POPS BEGINNING EARLY
SATURDAY AS SOME WEAK NORTHERN STREAM ENERGY SLIDES OFF TO THE
NORTH. POPS INCREASE SATURDAY NIGHT TO CHANCE...WITH LIKELY POPS FOR
MUCH OF THE FORECAST AREA SUNDAY.
GIVEN ANTECEDENT WARM AND HUMID CONDITIONS AHEAD OF THE COLD FRONT
AND SHOWALTER INDICES BELOW 0C COUPLED WITH INCREASING WIND PROFILES
FROM A 50-70 KNOT UPPER-LEVEL JET...THE POTENTIAL EXISTS FOR
STRONGER STORMS SUNDAY ACCOMPANYING THE COLD FRONT PASSAGE.
THE QUESTION WILL BE JUST HOW MUCH INSTABILITY THERE WILL BE
SUNDAY...BUT THERE CONTINUES TO BE A SIGNAL FOR MORE ROBUST
CONVECTION. WITH 850 HPA MOISTURE TRANSPORT VECTORS INDICATING RAPID
MOISTURE TRANSPORT INTO THE REGION AMIDST PWAT ANOMALIES OF 1-2
STANDARD DEVIATIONS...THE POTENTIAL ALSO EXISTS FOR SOME TORRENTIAL
RAINFALL WITH ANY CONVECTION THAT DEVELOPS.
THE COLD FRONT WILL CROSS THE FORECAST AREA SOMETIME IN THE LATE
SUNDAY-EARLY MONDAY TIMEFRAME...ENDING PRECIPITATION CHANCES ACROSS
MUCH OF THE FORECAST AREA. IT IS DURING THIS TIMEFRAME THAT THE LONG
RANGE GUIDANCE BEGINS TO DIVERGE WITH THE 12Z GFS CONTINUING TO
INDICATE THE FRONT STALLING SOMEWHERE ALONG THE EASTERN SEABOARD
WITH A WAVE OF LOW PRESSURE DEVELOPING ALONG IT DUE TO THE
AMPLIFICATION OF THE UPPER TROUGH...WHILE THE 12Z ECMWF MAINTAINS A
PROGRESSIVE POSITIVE-TILT ORIENTATION TO THE UPPER TROUGH. GIVEN THE
SOUTHWARD DISPLACEMENT OF THE BERMUDA HIGH...WILL SIDE WITH THE 12Z
ECMWF SOLUTION FAVORING DECREASING PRECIPITATION CHANCES VERSUS A
POTENTIAL HEAVY RAIN EVENT ACCORDING TO THE GFS FOR EARLY NEXT WEEK.
WITH HUMID CONDITIONS IN PLACE...THE FIRST WEEKEND OF JUNE WILL FEEL
A LOT LIKE THE DOG DAYS OF SUMMER AS HIGH TEMPERATURES FRIDAY AND
SATURDAY REACH WELL INTO THE 80S...WITH POCKETS OF NEAR 90 AND
POTENTIALLY EVEN LOW 90S IN THE MID HUDSON VALLEY. THE RECORD HIGH
FOR ALBANY ON FRIDAY IS 92 DEGREES SET IN 1937 AND 94 DEGREES ON
SATURDAY SET IN 1918. TEMPERATURES WILL REMAIN IN THE 80S FOR SUNDAY
AHEAD OF THE COLD FRONT. THE PASSAGE OF THE COLD FRONT WILL USHER IN
CANADIAN HIGH PRESSURE AND COOLER TEMPERATURES...WITH HIGHS IN THE
UPPER 60S/LOWER 70S FOR THE START OF NEXT WEEK. LOW TEMPERATURES
WILL GENERALLY BE IN THE UPPER 50S TO MID 60S BEFORE COOLING INTO
THE UPPER 40S-MID 50S FOR THE START OF NEXT WEEK.
&&
.AVIATION /02Z WEDNESDAY THROUGH SUNDAY/...
MVFR FLYING CONDITIONS ARE EXPECTED TONIGHT AS
SHOWERS/THUNDERSTORMS OVERSPREAD THE TAF SITES. CONDITIONS WILL
BRIEFLY IMPROVE TO VFR WEDNESDAY MORNING BEFORE A RENEWED THREAT
OF SHOWERS/THUNDERSTORMS WEDNESDAY AFTERNOON IMPACTS FLYING
CONDITIONS ONCE AGAIN.
TONIGHT...A BATCH OF SHOWERS WILL CONTINUE TO MOVE THROUGH CENTRAL
NEW YORK OVER THE NEXT COUPLE OF HOURS...HOWEVER DISSIPATING
THROUGH TIME. THESE SHOWERS WILL LIKELY IMPACT KPOU OVER THE NEXT
COUPLE OF HOURS...AND HAVE INDICATED A TEMPO GROUP FOR MVFR
CONDITIONS. ELSEWHERE...PRECIPITATION COVERAGE WILL INCREASE AT
ALL TAF SITES BY 03Z AS A CLUSTER OF SHOWERS/THUNDERSTORMS
OVERSPREADS THE REGION BRINGING OCCASIONAL MVFR...AND INTERMITTENT
IFR FLYING CONDITIONS ESPECIALLY AT KPSF. WINDS WILL SOUTHERLY AND
LIGHT GENERALLY 5-10 KNOTS.
WEDNESDAY...PRECIPITATION COVERAGE SHOULD END FROM WEST TO EAST BY
THE MORNING HOURS AS FLYING CONDITIONS IMPROVE TO VFR WITH THE
PASSAGE OF A WARM FRONT. THIS WARM FRONT WILL PROVIDE THE FOCUS
FOR RENEWED SHOWER/THUNDERSTORM DEVELOPMENT BY THE AFTERNOON HOURS
AND PERSIST THROUGH THE REMAINDER OF THE TAF PERIOD. WINDS
WEDNESDAY WILL BE SOUTHERLY GENERALLY 7-13 KNOTS.
OUTLOOK...
THU-SUN...VFR/MVFR. CHC PM -TSRA EACH DAY. LATE NIGHT AND/OR
EARLY MORNING MVFR/IFR ASSOC WITH FOG POSSIBLE.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS OVER THE NEXT SEVERAL DAYS.
S-SE WINDS WILL BE AROUND 5 TO 15 MPH TONIGHT WITH RH VALUES
RECOVERING TO NEAR 100 PERCENT. SHOWERS AND THUNDERSTORMS ARE LIKELY
TONIGHT AND WEDNESDAY. ALSO ON WEDNESDAY...RH VALUES WILL ONLY DROP
TO BETWEEN 50 AND 65 PERCENT WITH S-SW WINDS AT 10 TO 20 MPH WITH
GUSTS OVER 25 MPH.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE EXPECTED ACROSS THE HSA FOR THE
NEXT 5 DAYS.
RIVER FLOWS HAVE RECEDED THE PAST FEW DAYS AFTER THE HEAVIER RAINS
FROM LAST WEEK INTO THE WEEKEND. AN APPROACHING WARM FRONT WILL
ALLOW FOR SOME SHOWERS AND POSSIBLE THUNDERSTORMS INTO WEDNESDAY
MORNING. ADDITIONAL THUNDERSTORMS ARE POSSIBLE ON WEDNESDAY...WITH
JUST ISOLATED TO WIDELY SCATTERED THUNDERSTORM ACTIVITY ON THURSDAY
THROUGH SATURDAY.
WHILE WIDESPREAD HEAVY RAINFALL IS NOT ANTICIPATED THIS WEEK...ANY
AREAS THAT SEES REPEATED SHOWERS OR THUNDERSTORMS MAY LOCALLY SEE
SOME WITHIN BANK RISES ON RIVERS AND STREAMS. DUE TO THE SCATTERED
NATURE OF THE SHOWERS AND THUNDERSTORMS...QPF AMOUNTS WILL BE
VARIABLE ACROSS THE REGION. THE LATEST WEATHER PREDICTION CENTER
/WPC/ QPF FORECAST CALLS FOR UP TO AN INCH OF RAINFALL ACROSS THE
REGION THROUGH SATURDAY EVENING...ALTHOUGH THIS WILL ULTIMATELY
DEPEND ON THE EXACT TRACK OF ANY SHOWERS OR THUNDERSTORMS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...GJM
NEAR TERM...IRL/GJM
SHORT TERM...GJM
LONG TERM...IRL
AVIATION...IRL
FIRE WEATHER...GJM
HYDROLOGY...GJM
AREA FORECAST DISCUSSION
NWS ALBANY NY
752 PM EDT TUE MAY 28 2013
.SYNOPSIS...
A WARM FRONT WILL APPROACH THE REGION FROM THE SOUTHWEST
TONIGHT... AND MOVE THROUGH THE REGION EARLY WEDNESDAY. MUCH
WARMER TEMPERATURES ARE EXPECTED FOR THE REMAINDER OF THE WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
AS OF 745 PM EDT...INITIAL PRECIPITATION ACROSS SOUTHERN ZONES HAS
EXITED/DISSIPATED FROM THE FORECAST AREA. SOME ADDITIONAL
OVERRUNNING PRECIPITATION ACROSS CENTRAL NEW YORK WILL CONTINUE TO
MOVE EASTWARD...BUT CONTINUES TO DISSIPATE WITH TIME LIKE ITS
PREDECESSOR AS LATEST SURFACE OBSERVATIONS INDICATE THE WARM FRONT
STILL REMAINING WELL SOUTH OF THE FORECAST AREA ACROSS CENTRAL PA.
MEANWHILE...A CLUSTER OF THUNDERSTORMS CONTINUES TO MOVE
EAST/SOUTHEAST FROM THE GREAT LAKES REGION. CURRENT THINKING IS THAT
THIS BATCH OF SHOWERS/THUNDERSTORMS WILL IMPACT THE FORECAST AREA
AFTER 03Z. THE QUESTION REMAINS TO WHAT EXTENT PRECIPITATION
COVERAGE WILL BE THIS EVENING/TONIGHT...AS LATEST HRRR RUNS INDICATE
THE HEAVIEST QPF FALLING SOUTH OF THE FORECAST AREA WHILE OTHER
MESOSCALE MODELS AND THE NAM/GFS CAMP INDICATE A MORE NORTHERN
TRACK. HAVE ADJUSTED POPS SIGNIFICANTLY DOWNWARD TO ACCOUNT FOR
UNCERTAINTY BUT HAVE GENERALLY INDICATED CHANCE POPS THROUGH THE
EVENING HOURS...AND INCREASING TO LIKELY AFTER MIDNIGHT AS SOME
BETTER OVERRUNNING LIFT/ELEVATED INSTABILITY SHOULD ALLOW FOR AN
INCREASE IN SHOWER/THUNDERSTORM COVERAGE ACROSS THE FORECAST AREA.
RAINFALL AMOUNTS SHOULD GENERALLY BE BETWEEN A TENTH AND QUARTER
OF AN INCH.
LOWS TONIGHT WILL SETTLE IN THE UPPER 40S/LOWER 50S IN PORTIONS OF
THE ADIRONDACKS TO MID/UPPER 50S ACROSS THE MID HUDSON VALLEY.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY/...
OUR REGION WILL BE SITUATED ON THE NORTHERN FRINGE OF A BUILDING
RIDGE ACROSS THE EASTERN CONUS ON WEDNESDAY. AT THE SFC...WE WILL
BE POKING INTO THE WARM SECTOR AS THE WARM FRONT WILL BE LIFTING
ACROSS THE REGION. THE WARM FRONT WILL BE MOVING ACROSS THE THE
REGION WEDNESDAY MORNING...SO HAVE CONTINUED LIKELY POPS FOR A FEW
HOURS...ESPECIALLY ACROSS THE NORTH.
AFTERWARD...SOME BREAKS OF SUN WILL OCCUR...ESP FOR VALLEY AREAS.
A SHORTWAVE WILL BE MOVING WITHIN THE STRONG W-SW FLOW ALOFT
ACROSS ONTARIO TOWARDS NORTHERN NY FOR THE AFTN HOURS. THE AMOUNT OF
SUNSHINE THAT OCCURS WILL BE CRITICAL...AS THIS WILL DETERMINE JUST
HOW MUCH INSTABILITY CAN BUILD UP. MODELS SHOW SHEAR VALUES BETWEEN
30 AND 40 KTS...AND CAPE VALUES OF 500-1500 J/KG. SPC CONTINUES TO
HAS PLACE OUR REGION IN A SLIGHT RISK FOR SEVERE WX AND HAS EVEN
EXPANDED THE SIZE OF THE AREA...AND IT APPEARS THAT WE WILL HAVE
SEVERAL INGREDIENTS IN PLACE FOR SOME GUSTY TSTMS.
HAVE 40 TO 50 PERCENT FOR SHOWERS/TSTMS. HAVE TRENDED MAX TEMPS
TOWARDS THE WARMER MAV GUIDANCE WITH HIGHS IN THE MID 70S TO MID
80S.
THE CHANCE FOR TSTMS WILL BE DECREASING TO ONLY SLIGHT CHANCE LATE
WEDNESDAY NIGHT AS THE SHORTWAVE MOVES EASTWARD...AND SFC HEATING
DIMINISHES. LOWS WILL BE IN THE MID 50S TO MID 60S.
850 HPA WILL RISE TO 16-18 DEGREES C ON THURSDAY...WITH THE 500 HPA
RIDGE CENTERED OVER THE DELMARVA. IT WILL BE WARM AND MUGGY...WITH
MAX TEMPS IN THE UPPER TO LOWER 90S. THE SFC BOUNDARY SHOULD BE
LOCATED FAR ENOUGH TO NORTH OF THE AREA FOR LITTLE LARGE SCALE
FORCING TO BE IN PLACE ACROSS OUR AREA...SO WIDESPREAD CONVECTION IS
NOT ANTICIPATED. MOST AREAS WILL LIKELY BE CAPPED AS WELL. HAVE
ONLY FORECAST A SLIGHT CHANCE OF TSTMS DURING THE AFTERNOON.
WITH THE RIDGE AND STRONG CAP STILL OVER THE REGION THURSDAY
NIGHT...HAVE NOT FORECAST ANY PCPN. IT WILL REMAIN WARM AND MUGGY
WITH LOWS IN THE UPPER 50S TO MID 60S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
THE LONG TERM WILL BE CHARACTERIZED BY INCREASING TEMPERATURES AND
HUMIDITY ALONG WITH CHANCES FOR SHOWERS AND THUNDERSTORMS AS A COLD
FRONT CROSSES THE REGION DURING THE WEEKEND.
LONG RANGE GUIDANCE CONTINUES TO BE IN EXCELLENT AGREEMENT HANDLING
MUCH OF THE LONG TERM PERIOD WITH BOTH THE 12Z GFS/ECMWF AND VARIOUS
ENSEMBLE MEMBERS DEPICTING A LARGE WARM CORE HIGH ACROSS THE EASTERN
THIRD OF THE NATION. THIS SYNOPTIC SETUP WILL BE PREVALENT THROUGH
MUCH OF THE FIRST WEEKEND OF JUNE...ALLOWING FOR A PERSISTENT
SOUTHWESTERLY RETURN FLOW TRANSPORT OF WARM AND HUMID AIR ACROSS THE
REGION AS MANY LOCATIONS ACROSS THE FORECAST AREA LOOK TO REACH 90
DEGREES FOR THE FIRST TIME IN 2013 ON FRIDAY.
A PATTERN SHIFT WILL START TO SLOWLY TAKE PLACE BEGINNING
SATURDAY...AS AN UPPER-LEVEL TROUGH AND ASSOCIATED SURFACE LOW
PRESSURE SYSTEM AND COLD FRONT APPROACH FROM THE UPPER MIDWEST. WITH
THE LARGE ANTICYCLONIC BERMUDA CIRCULATION FIRMLY ENTRENCHED ACROSS
THE EASTERN CONUS AND A POSITIVE-TILT ORIENTATION TO THE UPSTREAM
TROUGH...THERE REMAINS SOME UNCERTAINTY REGARDING THE EXACT TIMING
OF THE COLD FRONTAL PASSAGE ACROSS THE FORECAST AREA.
REGARDLESS...HAVE INTRODUCED SLIGHT CHANCE POPS BEGINNING EARLY
SATURDAY AS SOME WEAK NORTHERN STREAM ENERGY SLIDES OFF TO THE
NORTH. POPS INCREASE SATURDAY NIGHT TO CHANCE...WITH LIKELY POPS FOR
MUCH OF THE FORECAST AREA SUNDAY.
GIVEN ANTECEDENT WARM AND HUMID CONDITIONS AHEAD OF THE COLD FRONT
AND SHOWALTER INDICES BELOW 0C COUPLED WITH INCREASING WIND PROFILES
FROM A 50-70 KNOT UPPER-LEVEL JET...THE POTENTIAL EXISTS FOR
STRONGER STORMS SUNDAY ACCOMPANYING THE COLD FRONT PASSAGE.
THE QUESTION WILL BE JUST HOW MUCH INSTABILITY THERE WILL BE
SUNDAY...BUT THERE CONTINUES TO BE A SIGNAL FOR MORE ROBUST
CONVECTION. WITH 850 HPA MOISTURE TRANSPORT VECTORS INDICATING RAPID
MOISTURE TRANSPORT INTO THE REGION AMIDST PWAT ANOMALIES OF 1-2
STANDARD DEVIATIONS...THE POTENTIAL ALSO EXISTS FOR SOME TORRENTIAL
RAINFALL WITH ANY CONVECTION THAT DEVELOPS.
THE COLD FRONT WILL CROSS THE FORECAST AREA SOMETIME IN THE LATE
SUNDAY-EARLY MONDAY TIMEFRAME...ENDING PRECIPITATION CHANCES ACROSS
MUCH OF THE FORECAST AREA. IT IS DURING THIS TIMEFRAME THAT THE LONG
RANGE GUIDANCE BEGINS TO DIVERGE WITH THE 12Z GFS CONTINUING TO
INDICATE THE FRONT STALLING SOMEWHERE ALONG THE EASTERN SEABOARD
WITH A WAVE OF LOW PRESSURE DEVELOPING ALONG IT DUE TO THE
AMPLIFICATION OF THE UPPER TROUGH...WHILE THE 12Z ECMWF MAINTAINS A
PROGRESSIVE POSITIVE-TILT ORIENTATION TO THE UPPER TROUGH. GIVEN THE
SOUTHWARD DISPLACEMENT OF THE BERMUDA HIGH...WILL SIDE WITH THE 12Z
ECMWF SOLUTION FAVORING DECREASING PRECIPITATION CHANCES VERSUS A
POTENTIAL HEAVY RAIN EVENT ACCORDING TO THE GFS FOR EARLY NEXT WEEK.
WITH HUMID CONDITIONS IN PLACE...THE FIRST WEEKEND OF JUNE WILL FEEL
A LOT LIKE THE DOG DAYS OF SUMMER AS HIGH TEMPERATURES FRIDAY AND
SATURDAY REACH WELL INTO THE 80S...WITH POCKETS OF NEAR 90 AND
POTENTIALLY EVEN LOW 90S IN THE MID HUDSON VALLEY. THE RECORD HIGH
FOR ALBANY ON FRIDAY IS 92 DEGREES SET IN 1937 AND 94 DEGREES ON
SATURDAY SET IN 1918. TEMPERATURES WILL REMAIN IN THE 80S FOR SUNDAY
AHEAD OF THE COLD FRONT. THE PASSAGE OF THE COLD FRONT WILL USHER IN
CANADIAN HIGH PRESSURE AND COOLER TEMPERATURES...WITH HIGHS IN THE
UPPER 60S/LOWER 70S FOR THE START OF NEXT WEEK. LOW TEMPERATURES
WILL GENERALLY BE IN THE UPPER 50S TO MID 60S BEFORE COOLING INTO
THE UPPER 40S-MID 50S FOR THE START OF NEXT WEEK.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
MVFR FLYING CONDITIONS ARE EXPECTED TONIGHT AS
SHOWERS/THUNDERSTORMS OVERSPREAD THE TAF SITES. CONDITIONS WILL
BRIEFLY IMPROVE TO VFR WEDNESDAY MORNING BEFORE A RENEWED THREAT
OF SHOWERS/THUNDERSTORMS WEDNESDAY AFTERNOON IMPACTS FLYING
CONDITIONS ONCE AGAIN.
TONIGHT...A BATCH OF SHOWERS WILL CONTINUE TO MOVE THROUGH CENTRAL
NEW YORK OVER THE NEXT COUPLE OF HOURS...HOWEVER DISSIPATING
THROUGH TIME. THESE SHOWERS WILL LIKELY IMPACT KPOU OVER THE NEXT
COUPLE OF HOURS...AND HAVE INDICATED A TEMPO GROUP FOR MVFR
CONDITIONS. ELSEWHERE...PRECIPITATION COVERAGE WILL INCREASE AT
ALL TAF SITES BY 03Z AS A CLUSTER OF SHOWERS/THUNDERSTORMS
OVERSPREADS THE REGION BRINGING OCCASIONAL MVFR...AND INTERMITTENT
IFR FLYING CONDITIONS ESPECIALLY AT KPSF. WINDS WILL SOUTHERLY AND
LIGHT GENERALLY 5-10 KNOTS.
WEDNESDAY...PRECIPITATION COVERAGE SHOULD END FROM WEST TO EAST BY
THE MORNING HOURS AS FLYING CONDITIONS IMPROVE TO VFR WITH THE
PASSAGE OF A WARM FRONT. THIS WARM FRONT WILL PROVIDE THE FOCUS
FOR RENEWED SHOWER/THUNDERSTORM DEVELOPMENT BY THE AFTERNOON HOURS
AND PERSIST THROUGH THE REMAINDER OF THE TAF PERIOD. WINDS
WEDNESDAY WILL BE SOUTHERLY GENERALLY 7-13 KNOTS.
OUTLOOK...
THU-SUN...VFR/MVFR. CHC PM -TSRA EACH DAY. LATE NIGHT AND/OR
EARLY MORNING MVFR/IFR ASSOC WITH FOG POSSIBLE.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS OVER THE NEXT SEVERAL DAYS.
S-SE WINDS WILL BE AROUND 5 TO 15 MPH TONIGHT WITH RH VALUES
RECOVERING TO NEAR 100 PERCENT. SHOWERS AND THUNDERSTORMS ARE LIKELY
TONIGHT AND WEDNESDAY. ALSO ON WEDNESDAY...RH VALUES WILL ONLY DROP
TO BETWEEN 50 AND 65 PERCENT WITH S-SW WINDS AT 10 TO 20 MPH WITH
GUSTS OVER 25 MPH.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE EXPECTED ACROSS THE HSA FOR THE
NEXT 5 DAYS.
RIVER FLOWS HAVE RECEDED THE PAST FEW DAYS AFTER THE HEAVIER RAINS
FROM LAST WEEK INTO THE WEEKEND. AN APPROACHING WARM FRONT WILL
ALLOW FOR SOME SHOWERS AND POSSIBLE THUNDERSTORMS INTO WEDNESDAY
MORNING. ADDITIONAL THUNDERSTORMS ARE POSSIBLE ON WEDNESDAY...WITH
JUST ISOLATED TO WIDELY SCATTERED THUNDERSTORM ACTIVITY ON THURSDAY
THROUGH SATURDAY.
WHILE WIDESPREAD HEAVY RAINFALL IS NOT ANTICIPATED THIS WEEK...ANY
AREAS THAT SEES REPEATED SHOWERS OR THUNDERSTORMS MAY LOCALLY SEE
SOME WITHIN BANK RISES ON RIVERS AND STREAMS. DUE TO THE SCATTERED
NATURE OF THE SHOWERS AND THUNDERSTORMS...QPF AMOUNTS WILL BE
VARIABLE ACROSS THE REGION. THE LATEST WEATHER PREDICTION CENTER
/WPC/ QPF FORECAST CALLS FOR UP TO AN INCH OF RAINFALL ACROSS THE
REGION THROUGH SATURDAY EVENING...ALTHOUGH THIS WILL ULTIMATELY
DEPEND ON THE EXACT TRACK OF ANY SHOWERS OR THUNDERSTORMS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...GJM
NEAR TERM...IRL/GJM
SHORT TERM...GJM
LONG TERM...IRL
AVIATION...IRL
FIRE WEATHER...GJM
HYDROLOGY...GJM
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1201 AM EDT WED MAY 29 2013
.SYNOPSIS...
A WARM FRONT WILL LIFT NORTHEAST OF OUR REGION BY DAYBREAK
WEDNESDAY. THEREAFTER...HIGH PRESSURE WILL BE RIDGED FROM THE
CENTRAL ATLANTIC TO THE CAROLINAS WEDNESDAY THROUGH THE WEEKEND
PROVIDING A PROBABLE EARLY SEASON HEAT WAVE OF 3 TO 5 DAYS. A LOW
PRESSURE SYSTEM OVER THE GREAT LAKES SUNDAY WILL MOVE TO QUEBEC
WITH ITS COLD FRONT TRAILING SOUTHWARD ALONG THE EAST COAST EARLY
NEXT WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
A WARM FRONT IS DRAPED ACROSS SOUTHERN NEW JERSEY AND NORTH/CENTRAL
DELMARVA LATE THIS EVENING. THE WARM FRONT WILL SLOWLY DRIFT
NORTHEASTWARD OVERNIGHT. NORTH OF THE BOUNDARY, LOW CLOUDS AND
FOG WILL PERSIST, WHILE SOUTH OF THE FRONT, WE DO NOT EXPECT FOG
TO DEVELOP UNTIL OVERNIGHT.
WIDELY SCATTERED SHOWERS IN OUR REGION ARE ON THE WANE. THE VIGOROUS
CONVECTION ALONG THE NYS/PA BORDER WILL CONTINUE WEAKENING AS IT
MOVES EAST OVERNIGHT AND MAY NOT MAKE IT INTO OUR FORECAST
AREA...OR AT THE VERY WORST...JUST SKIM MOUNT POCONO AND HIGH
POINT BETWEEN 3 AM AND 6 AM.
THE PAST TWO CYCLES OF THE SPCWRF HAD WHAT I THOUGHT WERE EXCELLENT
HOURLY RADAR SIMULATIONS OF WHAT HAS TRANSPIRED FROM LERIE TO THE
DELMARVA INCLUDING OUR FORECAST AREA. THAT SPCWRF IS RELIED ON
HEAVILY AGAIN FOR THE UPCOMING FORECAST FOR WED AND WED NIGHT.
WEDNESDAY...WE KNOW THA NAM HAS BEEN SPITTING OUT QPF IN OUR AREA
WEDNESDAY BUT I THINK ITS INCORRECT. THE TUESDAY EVENING CONVECTION
WAS ON A NEW 700MB JETLET ACROSS NYS AND AS IT MOVES EAST OF OUR
LONG WED MORNING THE KI DRIES WITH TIME. THEREFORE THE 12Z/28
SPCWRF COULD NOT SUSTAIN ANY DEEP CONVECTION INTO OUR I80 VICINITY
LATE WED AFTN. WE`LL CHECK THE 00Z/29 VERSION BUT ATTM..AM EXPECTING
THE THE SHORT WAVE CROSSING INTO NNE LATE WED TO ONLY DROP A TRAILING
WEAKENING BAND OF SHOWERS AND TSTMS INTO OUR FAR NORTHERN PORTION
OF THE AREA AROUND 00Z WED. NOT MUCH BULK SHEAR SUPPORT FOR SVR IN
OUR AREA BUT A GUSTY NW WIND OUTFLOW OF 35-40 KT IS POSSIBLE FROM
KMPO TO KFWN.
THEREFORE NO CONVECTION EXPECTED WED AS IT HEATS UP TO NEAR 90F.
SINCE THE NAM SPITS OUT QPF...THAT TRIMS ITS BL TEMP AND 2M TEMPS
BY 1-3 DEGS AND WE SEE THE DRY RAP MODEL FCSTG LOWER 90S FOR S NJ
AND THE PHILLY AREA. THAT MIGHT BE 2 DEGS TO HIGH FOR 15C AT 850
BUT ITS QUITE POSSIBLE THAT 90F WILL OCCUR AND THAT OUR HEAT WAVE
BEGINS AROUND 3PM THIS AFTN.
SW WIND GUST 15 MPH IN THE AFTN. COOLING SEA BREEZES WILL STRUGGLE
TO PENETRATE INLAND IN THIS GRADIENT FLOW BEHIND THE WFRONT AND
EVEN KACY SHOULD REACH 90F WITH ONLY THE NEAREST 3MI OF THE COAST
RECEIVING THE BENEFIT OF COOLING SLY OCEAN BREEZES.
SINCE OUR HI IS BELOW 96. NO HEAT ADVY NOR EXCESSIVE HEAT WATCHES
BUT EMERGENCY MANAGEMENT HAS BEEN BRIEFED ON THE PROBABLE 3-5 DAY
EARLY SEASON HEAT WAVE FOR THE I95 CORRIDOR.
GFS ML CAPE WILL RISE TO NEAR 1500J ALONG I95 WED AFTN. STRONG
CONVECTION IS LIKELY IN S NYS LATE IN THE DAY AND IT MAY HOLD
TOGETHER DOWN TO I80 IN THE EVENING?
GENERALLY 50 50 BLENDED GFS NAM GUIDANCE BUT USING THE WARMER 2M
TEMPS TO MODIFY THE PCPN TAINTED NAM OUTPUT.
PHL AROUND 89 TODAY AND 90-91 IN SNJ EVEN TO KACY AND S DE VCNTY KGED.
&&
.SHORT TERM /WEDNESDAY NIGHT/...
OTHER THAN THE TRAILING BAND OF DYING CONVECTION DRIFTING SEWD
FROM NYS INTO POSSIBLY THE I80 REGION...A WARM DRY SUMMERLIKE
NIGHT.
50 50 BLENDED 00Z/29 GFS/NAM GUIDANCE.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
5-WAVE MODEL GUIDANCE SHOWS A RATHER LARGE BERMUDA RIDGE SETTING UP
THROUGH THE END OF THE WEEKEND WITH WEAK UPSTREAM TROUGHING. THE
RIDGE LOOKS TO AMPLIFY TOWARDS THE END OF THE WEEK BEFORE SHIFTING
MORE TOWARDS THE EAST-NORTHEAST. THE LONGWAVE TROUGH WILL BEGIN TO
FILL BACK IN BEHIND THE DEPARTING RIDGE BY EARLY NEXT WEEK.
WITH THE WARM FRONT PROGRESSING TO OUR NORTHEAST ON THURSDAY MORNING
AND WINDS BEGINNING TO BACK, WE SHOULD BE DRYING OUT THE COLUMN SOME
ALOFT. WITH VERY LITTLE IN THE WAY OF UPPER LEVEL SUPPORT AND
SURFACE RIDGING JUST TO OUR EAST WE KEEP THE FORECAST THROUGH THE
FIRST PART OF THE LONGTERM FAIRLY DRY. AN ENSUING VERY HOT AND HUMID
AIRMASS WILL MOVE IN STARTING ON THURSDAY WHICH LOOKS TO COMMENCE
OUR FIRST HEAT WAVE OF THE SEASON. SURFACE DEWPOINTS WILL CLIMB INTO
THE LOW TO MID-60S DURING THE HEAT WAVE UNDER AN INCREASING
SOUTHWESTERLY FLOW. THIS WOULD LEAD TO HEAT INDEX VALUES INTO THE
LOW-90S..CLOSER TO THE ACTUAL TEMPERATURES...NO HEAT RELATED
HEADLINES NEEDED THUS FAR. CLOSER TO THE COAST IT LOOKS DOUBTFUL
THAT A SEABREEZE WILL BE ABLE TO BRING ANY RELIEF THIS WEEKEND (IF
THAT IS WHAT YOU ARE LOOKING FOR) GIVEN THE STRONGER LOW-LEVEL
SOUTHWESTERLY FLOW.
THE MID-LEVEL RIDGING WILL BEGIN TO SLIDE MORE TOWARDS THE EAST ON
SATURDAY ALLOWING OUR REGION TO BE ON THE PERIPHERY OF ITS
INFLUENCE. THIS WOULD PLACE US WITHIN THE RING OF FIRE TERRITORY
WHERE ANY PIECE OF ENERGY COULD EASILY INITIATE CONVECTION. THERE
LOOKS TO BE A WEAK LEE-SIDE TROUGH THAT WILL TRY TO PUSH INTO THE
REGION ON SATURDAY FROM THE WEST-SOUTHWEST BUT THE COLUMN LOOKS
RATHER DRY, EXCEPT FOR THE SURFACE LAYER. PWATS WILL BE AROUND 1.25
INCHES, RATHER NORMAL GIVEN THE TIME OF THE YEAR. GIVEN THAT WE
SHOULD BE AMPLY UNSTABLE WITH SOME WEAK DYNAMICS FURTHER NORTH WE
ONLY HAVE A SLIGHT CHANCE ACROSS THIS REGION ON SATURDAY EVENING.
AFTER A HOT SATURDAY LOWS SATURDAY NIGHT WILL STRUGGLE TO FALL
INTO THE 60`S IN SPOTS. A FRONTAL BOUNDARY WILL MOVE INTO THE
REGION SUNDAY AND MONDAY. THIS WILL INCREASE CLOUDS SUNDAY AND
KEEP TEMPERATURES BELOW THE 90 DEGREE MARK DURING THE DAY SUNDAY.
ENOUGH INSTABILITY WILL IN PLACE DURING THE AFTERNOON FOR A FEW
STORMS TO FIRE PARTICULARLY WEST OF PHILLY CLOSER TO THE FRONT
DURING THE AFTERNOON. GOOD OVERALL GUIDANCE AGREEMENT WITH MOST WX
ELEMENTS THROUGH SUNDAY.
RAIN CHANCES INCREASE WITH THE FRONTAL PASSAGE LATE SUNDAY NIGHT AND
MONDAY. ENSEMBLES BOTH GFS AND ECMWF SHOW THE FRONTAL PASSAGE DURING
THIS TIME FRAME WITH SOME VARIABILITY IN EXACTLY WHEN THE FRONT
PASSES THROUGH. ALSO THINKING MODELING COULD BE EITHER SLIGHTLY FASTER OR
SLOWER IN FUTURE RUNS. THIS PRECLUDES LIKELY POPS FROM THE FORECAST
ATTM. SHOWERS AND THUNDERSTORMS ARE EXPECTED WITH THE FRONTAL
PASSAGE. FRONTAL TIMING WILL ALSO CONTRIBUTE TO THE AMOUNT OF
INSTABILITY AND ANY THREAT FOR STRONG STORMS OR HEAVY RAINFALL. THIS
FRONTAL BOUNDARY WILL END THE HEAT WAVE WITH MORE SEASONABLE AIR
BEHIND THE FRONT. HIGH TEMPERATURES MONDAY AND THE WIND DIRECTION
WILL ALSO BE BOTH HIGHLY DEPENDENT ON FRONTAL TIMING. FOR NOW MAINLY
BASED TIMING OF EVENTS ALONG THE LINES OF THE WPC GUIDANCE WHICH MATCH
WELL WITH THE ENSEMBLE APPROACH TAKEN WITH THIS PART OF THE
FORECAST. SKIES WILL CLEAR OUT GRADUALLY TUESDAY. HAVE GRADUALLY
DECREASED SKY COVER AND CLOUDS ON THE DAY TUESDAY ACROSS THE
REGION.
&&
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THROUGH 12Z...IFR/LIFR CONDS IN ST/FOG MUCH OF E PA AND NNJ WITH
ISOLATED SHOWERS AND CALM WIND. FOR FAR S NJ AND DE...GENERALLY
OCNL MVFR VSBY IN FOG WITH S WIND.
AFTER 12Z WED...ANY REMAINING IFR/LIFR FOG/STRATUS QUICKLY DISSIPATES
BY 13Z AND BECOMES VFR SCT-BKN AOA 5000 FT WITH A SW WIND G15 KT IN
THE AFTN.
ISOLATED THUNDERSTORMS MAY DEVELOP DURING THE AFTERNOON IN THE POCONOS.
HOWEVER, THEIR TIMING AND COVERAGE REMAINS A LOW CONFIDENCE FORECAST
AND THEY WILL NOT BE MENTIONED IN THE TAFS.
WED NIGHT...A LINE OF DYING SHOWERS AND EMBEDDED TSTMS MAY SLIDE ESEWD
INTO THE POCONOS AND FAR NNJ AROUND 00Z/30. OTRW VFR WITH POSSIBLE
MVFR HAZE FOG TOWARD DAWN THURSDAY.
OUTLOOK...
THURSDAY - SATURDAY...VFR WITH SOUTHWESTERLY WINDS. POSSIBLE EARLY
MORNING HAZE MVFR VSBYS EACH MORNING.
SUNDAY...MAINLY VFR, ISOLATED THUNDERSTORMS LATE FOR PHL AND
POINTS NW. LOCALLY IFR TO MVFR IN ANY THUNDERSTORMS.
&&
.MARINE...
SEAS AND WINDS WERE FCST MUCH TOO HIGH ON THE ATLC WATERS TUE AFTN
AND 44009..WITH ITS WIND DATA PROBLEMS AND ALL..STILL BARELY JUST
MADE IT 5 FT AT 11PM EDT. WILL DISCONTINUE THE SCA FOR THE SNJ
AND DE WATERS PROBABLY AT 6 AM WED.
OTRW A GENERALLY SSW 10-20 KT FLOW PREVAILS WED AND WED NIGHT WITH
NO HEADLINE. A BIT OF VSBY RESTRICTION IN FOG AND HAZE TIL 9 AM
EDT AND POSSIBLY IN HAZE EARLY THURSDAY MORNING. WINDS WILL
PROBABLY TURN SSE ALONG THE COASTS FOR A TIME THIS WED AFTN BUT
HERE..THE WSW GRADIENT FLOW MAY PREVENT MUCH OF AN E OF S TURN.
OUTLOOK...
SUB-ADVISORY CONDITIONS IN STORE FOR OUR WATERS THROUGH A GOOD
PORTION OF THE OUTLOOK PERIOD. WINDS WILL GENERALLY BE FROM THE
SOUTH-SOUTHWEST BY THURSDAY AS HIGH PRESSURE, OFFSHORE, WILL
DOMINATE OUR SENSIBLE WEATHER. SEAS WILL GENERALLY BE AROUND 3
FEET ACROSS ALL THE WATERS. SEAS AND WINDS WILL BEGIN TO INCREASE
THROUGHOUT THE DAY ON SUNDAY AND MONDAY AND LOOK TO REACH SCA
CRITERIA.
&&
.RIP CURRENTS...
RIP CURRENT AWARENESS WEEK JUNE 2 THROUGH 8. PSA`S WILL AIR ON KPHI NWR
AND POST DAILY AROUND 545 AM. A SHORT AWARENESS PRESS CONFERENCE
IN SURF CITY - LBI, TUE JUNE 4 2PM FOR THOSE MEDIA REPRESENTATIVES
THAT ARE INTERESTED IN RAISING RIP CURRENT AWARENESS AND CONDITIONS
FAVORING UNGUARDED LIFE THREATENING DANGER IN THE OCEAN SURF ZONE.
MORE ON THIS IN THE AFD NEXT MONDAY JUNE 3.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT WEDNESDAY FOR ANZ453>455.
&&
$$
SYNOPSIS...DRAG/HEAVENER 1201A
NEAR TERM...DRAG/IOVINO/ROBERTSON 1201A
SHORT TERM...DRAG/IOVINO 1201A
LONG TERM...GAINES/HEAVENER
AVIATION...DRAG/GAINES/IOVINO/HEAVENER/ROBERTSON 1201A
MARINE...DRAG/GAINES/IOVINO/HEAVENER 1201A
RIP CURRENTS...1201A
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
958 PM EDT TUE MAY 28 2013
.SYNOPSIS...
A WARM FRONT WILL LIFT THROUGH THE REGION OVERNIGHT FOLLOWED BY HIGH
PRESSURE OFF THE EAST COAST ESTABLISHING ITSELF ON WEDNESDAY. THE
HIGH PRESSURE WILL SLOWLY MOVE FURTHER OUT TO SEA THROUGH THE
WEEKEND. A LOW PRESSURE SYSTEM WILL TRACK INTO THE GREAT LAKES
REGION AND PUSH A COLD FRONT THROUGH BY EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
A WARM FRONT IS DRAPED ACROSS SOUTHERN NEW JERSEY AND
NORTH/CENTRAL DELMARVA LATE THIS EVENING. THE WARM FRONT WILL
SLOWLY DRIFT NORTHWARD OVERNIGHT. NORTH OF THE BOUNDARY, LOW
CLOUDS AND FOG WILL PERSIST, WHILE SOUTH OF THE FRONT, WE DO NOT
EXPECT FOG TO DEVELOP UNTIL OVERNIGHT.
A COUPLE OF THUNDERSTORMS ARE ROLLING THROUGH THE SOUTHERN
DELMARVA WHERE SOME SUNSHINE EARLIER HELPED DESTABILIZE THE
ATMOSPHERE. THESE SHOULD NOT PERSIST MUCH LONGER AS DAYTIME
HEATING WANES, AND THEY CONTINUE TO MOVE TO THE COAST.
WE INCREASED POPS OVERNIGHT FOR OUR NORTHERN ZONES AS THERE IS
WIDESPREAD SHOWER/THUNDERSTORM ACTIVITY ACROSS NORTHWEST
PENNSYLVANIA/SOUTHEAST NEW YORK. THIS IS ASSOCIATED WITH A STRONG
SHORT WAVE/VORT MAX THAT WILL BE MOVING TOWARD OUR AREA AND
CLIPPING OUR NORTHERN ZONES OVERNIGHT. THE HRRR SHOWS THE ACTIVITY
DIMINISHING SOME OVERNIGHT AS IT MOVES EAST, BUT IT MAY HOLD
TOGETHER ENOUGH TO BRING SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS TO THE AREA.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
ANY LINGERING LOW CLOUDS AND PATCHY FOG SHOULD DISSIPATE QUICKLY ON
WEDNESDAY MORNING DUE TO THE HIGH LATE MAY SUN ANGLE. REGARDLESS, IT
APPEARS AS THOUGH THERE WILL BE A FAIR AMOUNT OF HIGH CLOUDINESS
OVERHEAD THROUGH THE DAY WITH SOME CUMULUS DEVELOPMENT IN THE
AFTERNOON DUE TO DAYTIME HEATING.
THE +15C ISOTHERM AT 850 HPA IS FORECAST TO DRIFT OVERHEAD FOR
WEDNESDAY. BEING THAT WE ARE NOT EXPECTING FULL SUNSHINE, WE WILL
CONTINUE TO FORECAST MAXIMUM TEMPERATURES MAINLY IN THE UPPER 80S,
EXCEPT IN THE ELEVATED TERRAIN UP NORTH AND FOR AREAS ALONG THE
COAST.
A SOUTHWEST WIND IS FORECAST TO BECOME ESTABLISHED FOR WEDNESDAY
WITH SUSTAINED SPEEDS AROUND 10 MPH AND GUSTS INTO THE TEENS.
SURFACE BASED CAPE VALUES ARE FORECAST TO RISE INTO THE 1000 TO 1500
J/KG RANGE OVER LAND FOR WEDNESDAY AFTERNOON BASED ON THE NAM
GUIDANCE. AS USUAL, THE GFS GUIDANCE IS MORE ROBUST THAN THE NAM
WITH EXPECTED VALUES IN THE 1700 TO 2200 J/KG RANGE. WE MAY SEE
POP-UP SHOWERS AND THUNDERSTORMS ON WEDNESDAY AFTERNOON. THE
ACTIVITY SHOULD NOT BE VERY FOCUSED WITH THE LACK OF ANY SIGNIFICANT
TRIGGER.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
5-WAVE MODEL GUIDANCE SHOWS A RATHER LARGE BERMUDA RIDGE SETTING UP
THROUGH THE END OF THE WEEKEND WITH WEAK UPSTREAM TROUGHING. THE
RIDGE LOOKS TO AMPLIFY TOWARDS THE END OF THE WEEK BEFORE SHIFTING
MORE TOWARDS THE EAST-NORTHEAST. THE LONGWAVE TROUGH WILL BEGIN TO
FILL BACK IN BEHIND THE DEPARTING RIDGE BY EARLY NEXT WEEK.
WITH THE WARM FRONT PROGRESSING TO OUR NORTHEAST ON THURSDAY MORNING
AND WINDS BEGINNING TO BACK, WE SHOULD BE DRYING OUT THE COLUMN SOME
ALOFT. WITH VERY LITTLE IN THE WAY OF UPPER LEVEL SUPPORT AND
SURFACE RIDGING JUST TO OUR EAST WE KEEP THE FORECAST THROUGH THE
FIRST PART OF THE LONGTERM FAIRLY DRY. AN ENSUING VERY HOT AND HUMID
AIRMASS WILL MOVE IN STARTING ON THURSDAY WHICH LOOKS TO COMMENCE
OUR FIRST HEAT WAVE OF THE SEASON. SURFACE DEWPOINTS WILL CLIMB INTO
THE LOW TO MID-60S DURING THE HEAT WAVE UNDER AN INCREASING
SOUTHWESTERLY FLOW. THIS WOULD LEAD TO HEAT INDEX VALUES INTO THE
LOW-90S..CLOSER TO THE ACTUAL TEMPERATURES...NO HEAT RELATED
HEADLINES NEEDED THUS FAR. CLOSER TO THE COAST IT LOOKS DOUBTFUL
THAT A SEABREEZE WILL BE ABLE TO BRING ANY RELIEF THIS WEEKEND (IF
THAT IS WHAT YOU ARE LOOKING FOR) GIVEN THE STRONGER LOW-LEVEL
SOUTHWESTERLY FLOW.
THE MID-LEVEL RIDGING WILL BEGIN TO SLIDE MORE TOWARDS THE EAST ON
SATURDAY ALLOWING OUR REGION TO BE ON THE PERIPHERY OF ITS
INFLUENCE. THIS WOULD PLACE US WITHIN THE RING OF FIRE TERRITORY
WHERE ANY PIECE OF ENERGY COULD EASILY INITIATE CONVECTION. THERE
LOOKS TO BE A WEAK LEE-SIDE TROUGH THAT WILL TRY TO PUSH INTO THE
REGION ON SATURDAY FROM THE WEST-SOUTHWEST BUT THE COLUMN LOOKS
RATHER DRY, EXCEPT FOR THE SURFACE LAYER. PWATS WILL BE AROUND 1.25
INCHES, RATHER NORMAL GIVEN THE TIME OF THE YEAR. GIVEN THAT WE
SHOULD BE AMPLY UNSTABLE WITH SOME WEAK DYNAMICS FURTHER NORTH WE
ONLY HAVE A SLIGHT CHANCE ACROSS THIS REGION ON SATURDAY EVENING.
AFTER A HOT SATURDAY LOWS SATURDAY NIGHT WILL STRUGGLE TO FALL
INTO THE 60`S IN SPOTS. A FRONTAL BOUNDARY WILL MOVE INTO THE
REGION SUNDAY AND MONDAY. THIS WILL INCREASE CLOUDS SUNDAY AND
KEEP TEMPERATURES BELOW THE 90 DEGREE MARK DURING THE DAY SUNDAY.
ENOUGH INSTABILITY WILL IN PLACE DURING THE AFTERNOON FOR A FEW
STORMS TO FIRE PARTICULARLY WEST OF PHILLY CLOSER TO THE FRONT
DURING THE AFTERNOON. GOOD OVERALL GUIDANCE AGREEMENT WITH MOST WX
ELEMENTS THROUGH SUNDAY.
RAIN CHANCES INCREASE WITH THE FRONTAL PASSAGE LATE SUNDAY NIGHT AND
MONDAY. ENSEMBLES BOTH GFS AND ECMWF SHOW THE FRONTAL PASSAGE DURING
THIS TIME FRAME WITH SOME VARIABILITY IN EXACTLY WHEN THE FRONT
PASSES THROUGH. ALSO THINKING MODELING COULD BE EITHER SLIGHTLY FASTER OR
SLOWER IN FUTURE RUNS. THIS PRECLUDES LIKELY POPS FROM THE FORECAST
ATTM. SHOWERS AND THUNDERSTORMS ARE EXPECTED WITH THE FRONTAL
PASSAGE. FRONTAL TIMING WILL ALSO CONTRIBUTE TO THE AMOUNT OF
INSTABILITY AND ANY THREAT FOR STRONG STORMS OR HEAVY RAINFALL. THIS
FRONTAL BOUNDARY WILL END THE HEAT WAVE WITH MORE SEASONABLE AIR
BEHIND THE FRONT. HIGH TEMPERATURES MONDAY AND THE WIND DIRECTION
WILL ALSO BE BOTH HIGHLY DEPENDENT ON FRONTAL TIMING. FOR NOW MAINLY
BASED TIMING OF EVENTS ALONG THE LINES OF THE WPC GUIDANCE WHICH MATCH
WELL WITH THE ENSEMBLE APPROACH TAKEN WITH THIS PART OF THE
FORECAST. SKIES WILL CLEAR OUT GRADUALLY TUESDAY. HAVE GRADUALLY
DECREASED SKY COVER AND CLOUDS ON THE DAY TUESDAY ACROSS THE
REGION.
&&
.AVIATION /02Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
IFR CONDITIONS REMAIN ACROSS MOST OF THE TAF SITES NORTH OF A
WARM FRONT THAT IS DRAPED ACROSS SOUTHERN NEW JERSEY AND
NORTH/CENTRAL DELMARVA. THIS FRONT IS EXPECTED TO SLOWLY DRIFT
NORTHWARD OVERNIGHT. NORTH OF THE BOUNDARY, IFR CLOUDS AND FOG ARE
EXPECTED TO PERSIST, WHILE SOUTH OF THE BOUNDARY, VFR CONDITIONS
WILL PERSIST EARLY, BEFORE THE POSSIBILITY OF FOG DEVELOPING
OVERNIGHT. THE MOVEMENT OF THE FRONT WILL BE TRICKY AND THE
FORECAST OVERNIGHT WILL DEPEND ON HOW FAST THE FRONT MOVES.
CONDITIONS ARE FORECAST TO BE MOSTLY IN THE VFR RANGE FOR WEDNESDAY
WITH MAINLY CIRRUS OVERHEAD ALONG WITH SCATTERED AFTERNOON CUMULUS.
A SOUTHWEST WIND AROUND 10 KNOTS WITH GUSTS INTO THE TEENS IS
EXPECTED. ISOLATED THUNDERSTORMS MAY DEVELOP DURING THE AFTERNOON.
HOWEVER, THEIR TIMING AND COVERAGE REMAINS A LOW CONFIDENCE FORECAST
AND THEY WILL NOT BE MENTIONED IN THE TAFS AT THIS TIME.
OUTLOOK...
THURSDAY - SATURDAY...VFR WITH SOUTHWESTERLY WINDS. POSSIBLE EARLY
MORNING HAZE MVFR VSBYS EACH MORNING.
SUNDAY...MAINLY VFR, ISOLATED THUNDERSTORMS LATE FOR PHL AND
POINTS NW. LOCALLY IFR TO MVFR IN ANY THUNDERSTORMS.
&&
.MARINE...
AS THE WARM FRONT CONTINUES TO LIFT THROUGH AND TO THE NORTH OF OUR
REGION TONIGHT, THE FLOW WILL SETTLE INTO THE SOUTH AND THAT SHOULD
REMAIN THE CASE FOR WEDNESDAY. WE WILL PROBABLY GET A SOUTHEASTERLY
WIND ON DELAWARE BAY FOR WEDNESDAY AFTERNOON, BASED ON CLIMATOLOGY.
WE CONTINUE TO EXPECT MARGINAL SMALL CRAFT ADVISORY CONDITIONS ON
OUR OCEAN WATERS FROM OCEAN CITY, NEW JERSEY SOUTHWARD THROUGH
TONIGHT. AS A RESULT, THE ADVISORY WILL REMAIN IN PLACE THERE.
ELSEWHERE, SUSTAINED WIND SPEEDS ARE FORECAST TO BE IN THE 10 TO 15
KNOT RANGE OR LESS WITH GUSTS OF 15 TO 20 KNOTS. WAVE HEIGHTS ON OUR
OCEAN WATERS NORTH OF OCEAN CITY, NEW JERSEY SHOULD REMAIN AT 4 FEET
OR LESS. WAVES ON DELAWARE BAY WILL BE MOSTLY IN THE 1 TO 3 FOOT
RANGE.
OUTLOOK...
SUB-ADVISORY CONDITIONS IN STORE FOR OUR WATERS THROUGH A GOOD
PORTION OF THE OUTLOOK PERIOD. WINDS WILL GENERALLY BE FROM THE
SOUTH-SOUTHWEST BY THURSDAY AS HIGH PRESSURE, OFFSHORE, WILL
DOMINATE OUR SENSIBLE WEATHER. SEAS WILL GENERALLY BE AROUND 3
FEET ACROSS ALL THE WATERS. SEAS AND WINDS WILL BEGIN TO INCREASE
THROUGHOUT THE DAY ON SUNDAY AND MONDAY AND LOOK TO REACH SCA
CRITERIA.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT WEDNESDAY FOR ANZ453>455.
&&
$$
SYNOPSIS...HEAVENER
NEAR TERM...ROBERTSON/IOVINO
SHORT TERM...IOVINO
LONG TERM...GAINES/HEAVENER
AVIATION...GAINES/IOVINO/HEAVENER
MARINE...GAINES/IOVINO/HEAVENER
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
922 PM EDT Tue May 28 2013
.NEAR TERM [Rest of Tonight]...
The previous forecast generally appears to be on track for
tonight. The potential for fog development appears to have
diminished. Some low stratus and minor patchy fog could develop in
the pre-dawn hours, in the coastal areas as well as the eastern
portion of the CWA. Expecting lows in the upper 60s and winds out
of the east for the remainder of the night.
&&
.SHORT TERM [Wednesday Through Thursday Night]...
An upper level ridge will remain in place over the eastern half of
the US during this period, with very weak flow aloft over the
Southeast. Combined with an area of high pressure at the surface,
this will lead to continued dry conditions in our CWA through
Wednesday morning. During the afternoon and early evening hours
Wednesday, there will be a slightly better chance of precipitation
in parts of north Florida and south central Georgia, as models are
suggesting that the Atlantic and Gulf Coast sea breezes could set
off some isolated thunderstorms. However, precipitation chances
will remain low during this period. Temperatures will remain
seasonable, with highs in the upper 80s-lower 90s, and lows in the
60s inland with lower 70s in coastal regions.
&&
.LONG TERM [Friday through Tuesday]...
A broad area of high pressure over the Southeast US and Atlantic
Ocean will remain in place from Thursday through the weekend,
resulting in easterly flow and lower than normal chances of
precipitation. The best chance at seeing isolated thunderstorms will
be in the eastern part of our CWA during this period, where the
Atlantic sea breeze may spark some convection each afternoon and
early evening as it collides with the Gulf sea breeze. Seasonable
temperatures should occur throughout the period, with highs
generally in the low 90s and lows in the mid-upper 60s. Looking
ahead to next week, a disturbance in the southern Gulf and Caribbean
is being shown by the GFS, but it is far too early to determine the
track or intensity of this possible feature.
&&
.AVIATION [Through 00 UTC Thursday]...
There was more boundary layer moisture than 24 hours ago, but the
5 KT surface winds should be enough to prevent fog tonight. However,
GFS MOS and the 20 UTC HRRR forecast areas of low cigs (IFR- around
700 ft) near dawn. We favored the HRRR, which forecasts these cigs
only at KTLH and KVLD, rather than the GFS MOS which has low cigs at
all terminals. Low cigs will lift by mid to late morning, followed
by VFR conditions. Isolated SHRA/TSRA are expected in the afternoon,
but the PoP is too low to mention in this TAF package.
&&
.MARINE...
A ridge of high pressure will remain along or north of the Gulf
Coast through the period with a prolonged period of easterly flow
continuing. As is typical in this flow regime, there will be periods
where wind speeds surge to cautionary or marginal advisory levels,
mainly during the overnight and morning hours each day.
&&
.FIRE WEATHER...
No fire weather concerns due to increasing gulf moisture
throughout the rest of the week.
&&
.HYDROLOGY...
Overall chances for and coverage of showers and thunderstorms will
be low through the weekend with no impacts to area rivers expected.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 68 91 69 91 69 / 10 10 10 10 10
Panama City 73 85 73 86 73 / 10 20 10 20 10
Dothan 68 90 70 90 71 / 10 10 10 10 10
Albany 67 90 69 90 70 / 0 10 10 10 10
Valdosta 66 91 69 91 69 / 10 10 10 10 10
Cross City 67 89 68 90 69 / 10 20 20 20 10
Apalachicola 74 85 74 86 75 / 10 20 10 10 10
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM/MARINE...WALSH/DVD
SHORT TERM/LONG TERM... LAHR/GODSEY
AVIATION/FIRE WEATHER... FOURNIER
HYDROLOGY...GODSEY
AREA FORECAST DISCUSSION
NWS MIAMI FL
1056 AM EDT MON MAY 27 2013
.UPDATE...
THE MORNING SURFACE ANALYSIS SHOWED THE RIDGE AXIS ORIENTED FROM
EAST TO WEST ACROSS NORTHERN FLORIDA AND THE NORTHERN GULF COAST
STATES WITH MODERATE EASTERLY FLOW STREAMING ACROSS OUR LOCAL
AREA. HIGHER MOISTURE HAS BEGUN TO LIFT NORTH ACROSS THE FLORIDA
STRAITS AND INTO THE SOUTHERN PORTIONS OF THE FLORIDA PENINSULA.
THE LATEST OBSERVATIONS AROUND THE LOCAL AREA SHOWED A DECENT
DEWPOINT GRADIENT ACROSS THE AREA WITH MID TO UPPER 60S AROUND THE
LAKE REGION AND LOWER 70S ACROSS THE SOUTHERN PORTION OF THE
PENINSULA. THE MODEL SOUNDING AT MIA REFLECTS THIS INCREASE WITH A
PRECIPITABLE WATER OF 1.42", WHICH WAS AROUND AN INCH YESTERDAY
EVENING. THE LATEST RADAR LOOP SHOWED THE BEST SHOWER COVERAGE
FARTHER SOUTH OVER THE FLORIDA STRAITS WITH MAINLY ISOLATED
COVERAGE OVER OUR SOUTHERN AREAS OR SOUTH OF A LINE FROM FORT
LAUDERDALE TO NAPLES. THE LATEST HRRR HAS INITIALIZED WELL WITH
THIS COVERAGE AND GENERALLY INDICATES THE BEST AFTERNOON COVERAGE
REMAINING OVER THE INTERIOR AND GULF COAST AREAS WITH THE MODERATE
DEEP EASTERLY FLOW IN PLACE. OUTSIDE OF A FEW MINOR TWEAKS TO THE
GRIDDED FORECAST DATABASE...THE PREVIOUS FORECAST REMAINS ON TRACK
WITH NO MAJOR UPDATES NECESSARY AT THIS TIME.
&&
.PREV DISCUSSION... /ISSUED 648 AM EDT MON MAY 27 2013/
AVIATION...
A STRONG EASTERLY FLOW WILL CONTINUE THROUGH THE TAF PERIOD. THIS
WILL EQUATE TO STRONGER SUSTAINED WINDS DURING THE DAY WITH GUSTS
TO 20 TO 25 KTS IN SOME LOCATIONS. ALSO, THIS WILL BRING INCREASED
MOISTURE AND SCATTERED SHOWERS DEVELOPING MID DAY ACROSS SOUTH
FLORIDA. CURRENT MODELS RUNS SHOW THE MAIN AREA OF SHOWERS SHOULD
BE INLAND AND IN THE FAR SOUTHERN PORTION OF THE AREA. GIVEN THIS,
HAVE REMOVED MENTION OF PRECIPITATION FOR NOW, WITH THE EXCEPTION
OF KTMB WHICH HAS VCSH AFTER 17Z. HOWEVER, THERE DOES REMAIN A
CHANCE FOR SHOWERS ALONG THE ATLANTIC COAST AND THERE IS ALSO A
SLIGHT CHANCE FOR A THUNDERSTORM TO DEVELOP IN THE LATE MORNING
THROUGH THE OVERNIGHT HOURS. HOWEVER, CONFIDENCE IS TOO LOW FOR
EITHER TO MENTION IN TAFS AT THIS TIME.
PREV DISCUSSION... /ISSUED 231 AM EDT MON MAY 27 2013/
SHORT TERM (TODAY THROUGH WEDNESDAY)...
WEAK SYNOPTIC FEATURES WILL AFFECT SOUTH FLORIDA EARLY THIS WEEK WITH
INCREASING MOISTURE AND INSTABILITY. A VERY STRONG SUBSIDENCE CAP
THAT HAS BEEN PERSISTENT THE PAST FEW DAYS WILL RAPIDLY ERODE THIS
MORNING ACCORDING TO FORECAST SOUNDINGS WITH PWAT INCREASING TO NEAR
NORMAL LEVELS FOR LATE MAY. CURRENTLY THIS IS AROUND ONE INCH BUT
WILL BE INCREASING TO AROUND 1.7-1.9 INCHES BY THIS AFTERNOON AND
CONTINUING THROUGH THE END OF THE WEEK. THIS ALREADY SOMEWHAT
EVIDENT FROM RADAR SIGNATURES WITH SCATTERED SHOWER ACTIVITY OVER
THE FLORIDA STRAITS. THERE HAS NOT BEEN ANY LIGHTNING AS YET BUT AS
THE ATMOSPHERE MOISTENS AND DESTABILIZES THERE COULD BE SOME ISOLATED
THUNDER BY THIS AFTERNOON ESPECIALLY OVER THE SOUTHERN PORTIONS. IN
ADDITION, BOTH THE GFS AND ECMWF ARE SHOWING A WEAK MID LEVEL LOW
DEVELOPING OFF THE SOUTHEAST COAST OF THE PENINSULA BY LATE TUESDAY
FURTHER DESTABILIZING CONDITIONS.
AT THE SURFACE, STRONG HIGH PRESSURE OVER THE SOUTHEAST STATES WILL
CONTINUE WHICH WILL RESULT IN A HIGH RISK OF RIP CURRENTS AT ALL OF
THE EAST COAST BEACHES. THIS WILL ALSO MAINTAIN AN INCREASING
SOUTHEAST FLOW WHILE AT THE SAME TIME DEEPENING SO THE STEERING FLOW
FOR CONVECTIVE ACTIVITY WILL BE FROM THE E-SE.
LONG TERM (WEDNESDAY NIGHT THROUGH SUNDAY)...
THE WEAK MID LEVEL TROUGH WILL MOVE LITTLE THROUGH THE END OF THE
WEEK KEEPING THE CHANCES FOR SHOWERS AND THUNDERSTORMS ELEVATED.
SURFACE HIGH PRESSURE WILL ALSO CONTINUE TO STRETCH FROM THE
ATLANTIC TO THE SOUTHEAST STATES AND THIS WILL RETAIN HIGH CHANCES
FOR RIP CURRENTS AT THE ATLANTIC BEACHES THROUGHOUT THE EXTENDED
PERIOD.
MARINE...
PERSISTENT EASTERLY WIND OF 15 TO 20 KNOTS AND OCCASIONALLY HIGHER
WILL KEEP SEAS ELEVATED THROUGH THE WEEK.
FIRE WEATHER...
DEEP TROPICAL MOISTURE WILL RETURN TO SOUTH FLORIDA TODAY AND
CONTINUE THROUGH THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 83 75 83 74 / 20 10 30 20
FORT LAUDERDALE 82 76 84 77 / 20 20 40 30
MIAMI 85 75 85 76 / 20 30 50 40
NAPLES 88 71 89 72 / 20 20 60 40
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...RIP CURRENT RISK THROUGH FRIDAY AFTERNOON FOR COASTAL BROWARD-
COASTAL MIAMI DADE-COASTAL PALM BEACH.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...85/AG
AVIATION/RADAR...10/CD
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
326 PM EDT MON MAY 27 2013
.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
LATEST RUC 50H FIELD OVERLAID ON SATELLITE WATER VAPOR IMAGERY
SHOWS SUBTLE DISTURBANCES EMBEDDED WITHIN THE NEARLY ZONAL FLOW
ALOFT. SURFACE ANALYSIS SHOWS THE SURFACE RIDGE SETTLING ALONG THE
MID ATLANTIC COAST AND ESTABLISHING A MOIST SOUTHERLY WIND FLOW THIS
AFTERNOON. A MODIFIED 12Z FFC SOUNDING AND SUPPORTED BY LATEST SPC
MESO ANALYSIS INDICATE AFTERNOON CAPES WILL TOP OUT AROUND 500-600
J/KG WITH A MODERATE MID LEVEL CAP. WEAK INSTABILITY... LACK OF DEEP
LAYER SHEAR AND FORCING SUGGEST THE GREATER CHANCE FOR ISOLATED
AFTERNOON EVENING SHOWERS AND THUNDERSTORMS WOULD BE NORTH GA WHERE
OROGRAPHIC LIFT AND SUBTLE UPPER DISTURBANCES MAY PROVIDE SUFFICIENT
FORCING FOR DEVELOPMENT. WILL CONTINUE TO SHOW ISOLATED THUNDER FOR
NORTH GA THIS AFTERNOON AND EVENING... AND ONCE AGAIN ON TUESDAY.
OTHERWISE... MODELS ARE IN GOOD AGREEMENT WITH SURFACE AND UPPER
LEVEL RIDGE BUILDING OVER THE STATE TUE-WED IN RESPONSE TO DEEPENING
LOW PRESSURE OVER THE PLAINS THROUGH MID WEEK. AS A RESULT... EXPECT
SLIGHTLY LESS OF A CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS NORTH
GA TUE AFTERNOON/EVENING... AND NIL CHANCE ON WEDNESDAY.
AS FOR TEMPS... LEANED SLIGHTLY COOLER THAN GUIDANCE FOR LOWS
TONIGHT WITH LIGHT WINDS UNDER MOSTLY CLEAR SKIES INITIALLY... ALTHO
EXPECT THE SSE FLOW TO ADVECT SOME LOW LEVEL STRATUS NORTHWARD FROM
ATLANTIC AND GULF TOWARD MORNING. THEN WENT WITH A MAV AND MET BLEND
FOR THE REMAINING PERIODS AS A WARMING TREND CONTINUES IN RESPONSE
BUILDING HIGH PRESSURE AND CONTINUED DRY CONDITIONS.
39
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
NO MAJOR CHANGES MADE TO THE EXTENDED FORECAST. THINGS CONTINUE TO
LOOK LIKE A MORE SUMMER- LIKE PATTERN DEVELOPING THIS WEEK. MODELS
IN GOOD AGREEMENT IN BUILDING THE H5 RIDGE OVER THE CWA THROUGH
THE UPCOMING WEEKEND. HIGH PRESSURE AT THE SURFACE WILL BE BECOME
CENTERED OFF THE EAST COAST. THIS WILL BRING AN EAST TO SOUTHEAST
SURFACE FLOW TO THE CWA THEREBY INCREASING HUMIDITIES THROUGH THE
WEEK. THERE COULD BE A FEW ISOLATED AFTERNOON/EVENING
THUNDERSTORMS DEVELOPING EACH AFTERNOON...BUT WITH THE H5 RIDGE
HOLDING FIRM OVER THE CWA...THIS RISK SHOULD BE LESS THAN 20
PERCENT. A COLD FRONT WILL MOVE INTO THE TENNESSEE VALLEY BY NEXT
WEEKEND AS THE UPPER RIDGE WEAKENS. AT THE SAME TIME A SHORT WAVE
MOVES INTO THE OHIO AND TENNESSEE VALLEYS. THIS WILL BRING A
SLIGHT CHANCE OF THUNDERSTORMS MAINLY TO NORTH GA SUNDAY AND
MONDAY.
01/17
&&
.AVIATION...
18Z UPDATE...
VFR CONDITIONS CONTINUE THRU THE PERIOD...ALTHO DEVELOPING CU
FIELD THIS AFTERNOON WILL LIKELY BECOME BKN BY 20-21Z. THIS BKN060
WILL LIKELY OCCUR AGAIN TUE AFTERNOON AS A MOIST SE WIND FLOW
PREVAILS. THESE SE WINDS WILL SPREAD LOW STRATUS (SCT010-020) INTO
ATLANTA TAF SITES BY 10-12Z TUE...BUT GUIDANCE HOLDS ANY BKN CIGS
SOUTH OF ATL AT THIS TIME. CURRENTLY...ALTHO AREA OBS SHOW A SSW
WIND... EXPECT WINDS TO BACK SSE BY 18-19Z... THEN REMAIN SE THRU
THE TAF PERIOD. WIND SPEEDS WILL BE 6-8KTS EACH AFTN...3-5KTS
OVERNIGHT. CHANCE OF TSRA TOO LOW TO MENTION IN TAFS AT THIS TIME.
//ATL CONFIDENCE...18Z UPDATE...
MEDIUM ON POTENTIAL FOR LOW STRATUS 10-12Z TUE.
HIGH ON ALL OTHER ELEMENTS.
39
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 59 87 60 87 / 10 10 10 5
ATLANTA 63 86 65 86 / 10 5 5 5
BLAIRSVILLE 58 83 57 82 / 20 20 20 5
CARTERSVILLE 59 87 62 88 / 10 10 10 5
COLUMBUS 63 88 64 89 / 5 5 5 5
GAINESVILLE 61 87 61 85 / 20 20 10 5
MACON 60 88 62 89 / 5 5 5 5
ROME 58 88 62 90 / 20 20 10 5
PEACHTREE CITY 57 86 59 86 / 10 5 5 5
VIDALIA 63 89 64 88 / 5 5 5 5
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...39
LONG TERM....01
AVIATION...39
AREA FORECAST DISCUSSION
NWS POCATELLO ID
905 AM MDT MON MAY 27 2013
.UPDATE...WV SAT IMAGERY SHOWS SHORTWAVE CIRCULATION EXITING
EASTERN IDAHO INTO SOUTHERN MONTANA THIS MORNING. RADAR SHOWS WEAK
CONVECTION ASSOCIATED WITH THIS FEATURE...BUT ALREADY PAST EASTERN
IDAHO. NEXT PACIFIC TROUGH ALREADY LINED UP ALONG COAST AND
PUSHING MOISTURE AND PRECIPITATION INTO THE PACNW STATES. GFS AND
NAM WITH SUPPORT FROM THE HRRR CONTINUE TO ADVERTISE WEAK
CONVECTION REMAINING ALONG THE NORTHEAST PORTIONS OF THE REGION
TODAY IN WAKE OF DEPARTING SHORTWAVE. NEGATIVE TILT TROUGH PUSHES
WELL INTO OREGON BY EARLY AFTERNOON...BEGINNING TO SPREAD LARGE
PRECIP SHIELD WITH EMBEDDED WEAK CONVECTION INTO WESTERN IDAHO.
TIMING WILL BE CLOSE BUT CANNOT RULE OUT WEAK PRECIPITATION MOVING
INTO WESTERN EDGES OF FORECAST AREA BY 00Z. BELIEVE BULK OF THE
PRECIPITATION WILL ARRIVE LATER TONIGHT. CURRENT FCST SHOWS TIMING
OF THESE FEATURES QUITE WELL AND THUS ANTICIPATE NO UPDATES TODAY. DMH
&&
.PREV DISCUSSION... /ISSUED 237 AM MDT MON MAY 27 2013/
DISCUSSION...UPPER TROUGH EVIDENT ON WV IMAGERY OVER THE ID/MT
BORDER AND EXITING THE AREA THIS MORNING. THIS SHOULD RESULT IN
FAIRLY DRY WEATHER OVER SOUTHEAST IDAHO TODAY. FURTHER UPSTREAM...A
SECOND SHORTWAVE IS POISED TO IMPACT THE PACIFIC NORTHWEST. THE
GREATEST FORCING OVER IDAHO WITH THIS NEXT SYSTEM WILL BE TUESDAY
MORNING AND AFTERNOON AS THE TROUGH MOVES EASTWARD AND DIPS
SOUTHWARD A BIT. PROJECTED PW VALUES ARE AROUND 0.5 TO 0.75
INCHES...WHICH IS ABOVE NORMAL FOR THIS TIME OF YEAR. HAVE NUDGED
UP POPS AND QPF FROM PREVIOUS FORECAST FOR TUESDAY AND TUESDAY
NIGHT. UPPER TROUGH THEN SHIFTS EASTWARD TUESDAY NIGHT ALLOWING
WEAK RIDGING TO MOVE ACROSS SOUTHERN IDAHO. THE UPPER JET STAYS
SOUTH OF OUR BORDER THROUGH MID-WEEK...KEEPING US IN THE
RELATIVELY COOLER AIR UNTIL THE WEEKEND. MODELS DEVELOP UPPER
RIDGE OVER THE AREA FOR NEXT WEEKEND AND SHOULD RESULT IN DRY
WEATHER AND WARMER TEMPERATURES. HINSBERGER &&
AVIATION...A LOW PRESSURE TROUGH WAS NOTED LIFTING NE THROUGH THE
AREA EARLY THIS MORNING WHILE A STRONGER PACIFIC WAVE WAS SHEARING
SE INTO THE OREGON/WASHINGTON COASTAL WATERS. MODELS SUGGEST THAT
THE INITIAL WAVE WILL CLEAR THE REGION THIS MORNING WITH FAIRLY DRY
CONDITIONS PREVAILING AT THE TERMINAL SITES THROUGHOUT THE DAY.
INCREASING MID AND UPPER LEVEL MOISTURE IS EXPECTED TO OVERSPREAD
THE REGION THIS EVENING AS THE NEXT UPSTREAM SYSTEM ADVANCES INTO
OREGON. LOWER CLOUDS AND SCATTERED SHOWERS WILL SPREAD ACROSS SE
IDAHO LATE TONIGHT/TUESDAY MORNING AS THE TROUGH SPREADS INTO SRN
IDAHO. MODEL CROSS SECTIONS SUGGEST AT LEAST MVFR CIGS AT KBYI AND
KSUN. HUSTON
FIRE WEATHER...AN UPPER LEVEL TROUGH WAS NOTED LIFTING NORTHEAST
INTO SOUTHWEST MONTANA EARLY THIS MORNING WHILE A DECENT PACIFIC
WAVE WAS OBSERVED SHEARING SOUTHEAST INTO THE OREGON/WASHINGTON
COASTAL WATERS. CONDITIONS ARE EXPECTED TO BE FAIRLY DRY TODAY
BEHIND THE EXITING WAVE WHILE INCREASING CLOUDS AND SHOWERS SPREAD
INTO THE AREA TONIGHT AS THE NEXT UPSTREAM WAVE MOVES INTO
SOUTHERN IDAHO. WIDESPREAD SHOWERS AND SCATTERED THUNDERSTORMS ARE
EXPECTED TUESDAY AND TUESDAY NIGHT AS THE UPPER TROUGH SHIFTS SLOWLY
THROUGH THE REGION. A SECONDARY DISTURBANCE FOLLOWS
WEDNESDAY...WHICH SHOULD SUPPORT SCATTERED SHOWERS AND THUNDERSTORMS
THROUGHOUT THE DAY...LINGERING INTO THURSDAY. IMPROVING CONDITIONS
ARE ANTICIPATED FRIDAY/SATURDAY AS A RIDGE OF HIGH PRESSURE MIGRATES
THROUGH THE REGION. HUSTON
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
907 PM CDT TUE MAY 28 2013
.DISCUSSION...
ISSUED 907 PM CDT TUE MAY 28 2013
WHILE MOST OF CENTRAL AND SOUTHEAST ILLINOIS HAS BEEN DRY THIS
EVENING...AN AREA OF VERY HEAVY RAINFALL OCCURRED ACROSS PORTIONS
OF KNOX...STARK AND MARSHALL COUNTIES. SPOTTER REPORTS AROUND 3
INCHES WERE RECEIVED ACROSS PARTS OF KNOX COUNTY. THIS RAINFALL
PRODUCED FLASH FLOODING IN SOME AREAS. THESE STORMS FORMED ALONG
AN AXIS OF HIGH INSTABILITY ON THE WARM SIDE OF A FRONT THAT
EXTENDS FROM THE CENTRAL PLAINS INTO THE GREAT LAKES.
COVERAGE AND INTENSITY OF PRECIPITATION UPSTREAM HAS BEEN ON THE
DECREASE OVERALL WITH DIMINISHING DIURNAL INSTABILITY.
HOWEVER...STILL EXPECT AT LEAST SCATTERED SHOWERS/STORMS THROUGH
THE NIGHT ACROSS THE NORTHWEST HALF OF THE FORECAST AREA. THESE
STORMS WILL BE AIDED BY AN INCREASING LOW LEVEL JET ALONG THE
SURFACE FRONT. HOWEVER...SOME OF THE HIGH RESOLUTION MODELS
SUGGEST THE CONVECTION WILL BE A LITTLE FURTHER SOUTH INTO THE
FORECAST AREA THAN IT HAS BEEN...LIKELY FIRING IN THE VICINITY OF
OUTFLOW BOUNDARIES FROM THE EARLY EVENING CONVECTION.
GOING FORECAST IS IN GOOD SHAPE OVERALL. ONLY PLAN TO TWEAK FOR
THE EXPECTED OVERNIGHT TRENDS.
BAK
&&
.AVIATION...
ISSUED 645 PM CDT TUE MAY 28 2013
PREDOMINANTLY VFR CONDITIONS EXPECTED ACROSS THE CENTRAL ILLINOIS
TERMINALS THROUGH THE 00Z TAF VALID TIME. CAN NOT RULE OUT A FEW
SHOWERS/STORMS FOR THE EVENING AND EARLY OVERNIGHT HOURS
TONIGHT...ALTHOUGH THE GREATEST CONCENTRATION OF PRECIPITATION
SHOULD FALL NORTH OF THE TERMINALS CLOSER TO A FRONTAL BOUNDARY TO
THE NORTHWEST OF THE AREA. SOUTHERLY WINDS SHOULD PERSIST TO THE
SOUTH OF THE BOUNDARY...OUTSIDE OF ANY LOCAL STORM IMPACTS...
BECOMING GUSTY DURING PEAK DIURNAL MIXING.
BAK
&&
.PREV DISCUSSION...
ISSUED 300 PM CDT TUE MAY 28 2013
COMPLICATED WEATHER PATTERN IN GENERAL MADE MORE COMPLICATED IN
THE MODELS WITH A STRUGGLE WITH THE PATTERN SHIFT OVERALL.
HOWEVER...FOR ALL THE NUANCES WITH THE WAVES MOVING THROUGH THE
FORECAST AREA...THE ONE AGREED UPON PORTION IN ALL THE OPERATIONAL
MODELS IS THAT CENTRAL ILLINOIS WILL BE RATHER WET THROUGH THE END
OF THE WEEK. WARM FRONT WELL TO THE NORTH OF THE CWA...LEAVING ILX
IN THE WARM SECTOR WITH WARM TEMPS AND DEWPOINTS IN A RATHER MUGGY
AIRMASS. THIS WARMTH AND MOISTURE WILL HELP TO FUEL ANY MCS REMNANTS/BOUNDARIES
THAT MOVE INTO THE FA...IN ADDITION TO THE OVERALL FRONT SCHEDULED
TO MOVE INTO THE MIDWEST AT MIDWEEK. WITH SWRLY FLOW ALOFT...THE
FRONT IS GOING TO LOSE ITS FORWARD MOMENTUM...SLOW MOVING...AND
SLOW TO EXIT. AS A RESULT...ANY WAVES THAT EJECT OUT OF THE SW AND
ALONG THE BOUNDARY WILL RESULT IN ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS. HEAVY RAIN IS LIKELY INVOF WHEREVER THE FRONT
LANDS...WHICH WILL NOT ONLY BE DIFFICULT TO PIN...FRONT WILL ALSO
END UP GETTING INFLUENCED GREATLY BY MESOSCALE INFLUENCES/COLD
POOLS/OUTFLOWS AS WELL. WITH GROUND ALREADY VERY SATURATED FROM
PREVIOUS RAINS...THE FLASH FLOODING THREAT MAY GET A BREAK
TOMORROW FOR PORTIONS OF CENTRAL ILLINOIS...BUT IT WILL BE BACK BY
THURSDAY.
SHORT TERM...TONIGHT THROUGH TOMORROW...
SCATTERED THUNDERSTORMS STILL POSSIBLE THROUGH THE EVENING WITH
CONVECTIVE INITIATION LIKELY TO THE WEST IN NRN MO JUST ACROSS THE
MISS RIVER VALLEY. BOTH RUC AND NMM/WRF KEEPING SOME
ACTIVITY...THOUGH THE RUC/RAP IS ACTUALLY CONFINING MUCH OF THE
ACTIVITY TO THE NORTH. THE 4KM WRF/NMM DEVELOPS MORE OF A LINEAR
COMPLEX THAT EVENTUALLY MOVES THROUGH THE FA TO THE SE AND WEAKENS
AS IT TRAVERSES THE CWA. SHOWER THREAT FINALLY DIMINISHES BRIEFLY
FOR WEDNESDAY...THOUGH THE THREAT OF ANY INTERACTION WITH THE WARM
FRONT TO THE NORTH RESULTS IN POPS ACROSS THE NRN TIER OF THE
STATE. WARM TEMPS...SOUTHERLY WINDS...AND ABUNDANT MOISTURE IN THE
BOUNDARY LAYER WILL PUSH HEAT INDEX VALUES INTO THE UPPER 80S/NEAR
90. WINDS WILL BE RATHER BREEZY AND HELP TO COUNTER SOME OF THE
EFFECTS...THOUGH CAUTION SHOULD BE USED BY ANYONE OUTDOORS
TOMORROW.
LONG TERM...THURSDAY THROUGH MONDAY...
THE WESTERN TROF DIGS IN...AMPLIFYING THE WAVE PATTERN OVER THE
CONUS AND LEAVING THE UPPER MIDWEST IN SWRLY FLOW...THROUGH
THURSDAY...WITH WARM TEMPS YET AGAIN ON THURSDAY. TEMPS IN THE NW
SHOULD BE SOMEWHAT DAMPENED HOWEVER...BY CLOUD COVER FROM
APPROACHING BOUNDARY. IN ADDITION...DIURNAL CURVE WILL LIKELY BE
SHATTERED BY THE CONVECTIVE ACTIVITY RUINING THE STEADY CLIMB OF
TEMPERATURES IN ANY ONE SPOT AHEAD OF THAT BOUNDARY. FORECAST
CONFIDENCE ABOUT DETAILS COMPLICATED WITH THE ELONGATED TROF IN
THE ECMWF/NAM IS PROVIDING A SLIGHTLY DIFFERENT SOLUTION WITH THE
SFC SYSTEM THAN THE NAM. THAT BEING SAID...THE ECMWF IS LOOKING A
BIT MORE LIKE THE GFS IN THE 12Z RUN. THOUGH EVERYONE IS IN
AGREEMENT ABOUT ENTERING A PROLONGED PERIOD OF PRECIP THROUGH DAY
5...THE DIFFERENCES IN THE MODELS WILL IMPACT THE DYNAMICS AND
ASSOCIATED SEVERE WEATHER THREAT. FORECASTING ONSET OF THE
HEAVIEST PRECIP ALONG THE APPROACHING FRONT. IN SUMMARY...THE RAIN
IS NOT OVER AS LONG AS THAT FRONT WITH THE NEXT SYSTEM GETS SLOWED
BY PARALLEL FLOW ALOFT.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 7 AM CDT WEDNESDAY FOR ILZ027>031-
036>038-040>043-047>053-061.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
645 PM CDT TUE MAY 28 2013
.DISCUSSION...
ISSUED 300 PM CDT TUE MAY 28 2013
COMPLICATED WEATHER PATTERN IN GENERAL MADE MORE COMPLICATED IN
THE MODELS WITH A STRUGGLE WITH THE PATTERN SHIFT OVERALL.
HOWEVER...FOR ALL THE NUANCES WITH THE WAVES MOVING THROUGH THE
FORECAST AREA...THE ONE AGREED UPON PORTION IN ALL THE OPERATIONAL
MODELS IS THAT CENTRAL ILLINOIS WILL BE RATHER WET THROUGH THE END
OF THE WEEK. WARM FRONT WELL TO THE NORTH OF THE CWA...LEAVING ILX
IN THE WARM SECTOR WITH WARM TEMPS AND DEWPOINTS IN A RATHER MUGGY
AIRMASS. THIS WARMTH AND MOISTURE WILL HELP TO FUEL ANY MCS REMNANTS/BOUNDARIES
THAT MOVE INTO THE FA...IN ADDITION TO THE OVERALL FRONT SCHEDULED
TO MOVE INTO THE MIDWEST AT MIDWEEK. WITH SWRLY FLOW ALOFT...THE
FRONT IS GOING TO LOSE ITS FORWARD MOMENTUM...SLOW MOVING...AND
SLOW TO EXIT. AS A RESULT...ANY WAVES THAT EJECT OUT OF THE SW AND
ALONG THE BOUNDARY WILL RESULT IN ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS. HEAVY RAIN IS LIKELY INVOF WHEREVER THE FRONT
LANDS...WHICH WILL NOT ONLY BE DIFFICULT TO PIN...FRONT WILL ALSO
END UP GETTING INFLUENCED GREATLY BY MESOSCALE INFLUENCES/COLD
POOLS/OUTFLOWS AS WELL. WITH GROUND ALREADY VERY SATURATED FROM
PREVIOUS RAINS...THE FLASH FLOODING THREAT MAY GET A BREAK
TOMORROW FOR PORTIONS OF CENTRAL ILLINOIS...BUT IT WILL BE BACK BY
THURSDAY.
SHORT TERM...TONIGHT THROUGH TOMORROW...
SCATTERED THUNDERSTORMS STILL POSSIBLE THROUGH THE EVENING WITH
CONVECTIVE INITIATION LIKELY TO THE WEST IN NRN MO JUST ACROSS THE
MISS RIVER VALLEY. BOTH RUC AND NMM/WRF KEEPING SOME
ACTIVITY...THOUGH THE RUC/RAP IS ACTUALLY CONFINING MUCH OF THE
ACTIVITY TO THE NORTH. THE 4KM WRF/NMM DEVELOPS MORE OF A LINEAR
COMPLEX THAT EVENTUALLY MOVES THROUGH THE FA TO THE SE AND WEAKENS
AS IT TRAVERSES THE CWA. SHOWER THREAT FINALLY DIMINISHES BRIEFLY
FOR WEDNESDAY...THOUGH THE THREAT OF ANY INTERACTION WITH THE WARM
FRONT TO THE NORTH RESULTS IN POPS ACROSS THE NRN TIER OF THE
STATE. WARM TEMPS...SOUTHERLY WINDS...AND ABUNDANT MOISTURE IN THE
BOUNDARY LAYER WILL PUSH HEAT INDEX VALUES INTO THE UPPER 80S/NEAR
90. WINDS WILL BE RATHER BREEZY AND HELP TO COUNTER SOME OF THE
EFFECTS...THOUGH CAUTION SHOULD BE USED BY ANYONE OUTDOORS
TOMORROW.
LONG TERM...THURSDAY THROUGH MONDAY...
THE WESTERN TROF DIGS IN...AMPLIFYING THE WAVE PATTERN OVER THE
CONUS AND LEAVING THE UPPER MIDWEST IN SWRLY FLOW...THROUGH
THURSDAY...WITH WARM TEMPS YET AGAIN ON THURSDAY. TEMPS IN THE NW
SHOULD BE SOMEWHAT DAMPENED HOWEVER...BY CLOUD COVER FROM
APPROACHING BOUNDARY. IN ADDITION...DIURNAL CURVE WILL LIKELY BE
SHATTERED BY THE CONVECTIVE ACTIVITY RUINING THE STEADY CLIMB OF
TEMPERATURES IN ANY ONE SPOT AHEAD OF THAT BOUNDARY. FORECAST
CONFIDENCE ABOUT DETAILS COMPLICATED WITH THE ELONGATED TROF IN
THE ECMWF/NAM IS PROVIDING A SLIGHTLY DIFFERENT SOLUTION WITH THE
SFC SYSTEM THAN THE NAM. THAT BEING SAID...THE ECMWF IS LOOKING A
BIT MORE LIKE THE GFS IN THE 12Z RUN. THOUGH EVERYONE IS IN
AGREEMENT ABOUT ENTERING A PROLONGED PERIOD OF PRECIP THROUGH DAY
5...THE DIFFERENCES IN THE MODELS WILL IMPACT THE DYNAMICS AND
ASSOCIATED SEVERE WEATHER THREAT. FORECASTING ONSET OF THE
HEAVIEST PRECIP ALONG THE APPROACHING FRONT. IN SUMMARY...THE RAIN
IS NOT OVER AS LONG AS THAT FRONT WITH THE NEXT SYSTEM GETS SLOWED
BY PARALLEL FLOW ALOFT.
HJS
&&
.AVIATION...
ISSUED 645 PM CDT TUE MAY 28 2013
PREDOMINANTLY VFR CONDITIONS EXPECTED ACROSS THE CENTRAL ILLINOIS
TERMINALS THROUGH THE 00Z TAF VALID TIME. CAN NOT RULE OUT A FEW
SHOWERS/STORMS FOR THE EVENING AND EARLY OVERNIGHT HOURS
TONIGHT...ALTHOUGH THE GREATEST CONCENTRATION OF PRECIPITATION
SHOULD FALL NORTH OF THE TERMINALS CLOSER TO A FRONTAL BOUNDARY TO
THE NORTHWEST OF THE AREA. SOUTHERLY WINDS SHOULD PERSIST TO THE
SOUTH OF THE BOUNDARY...OUTSIDE OF ANY LOCAL STORM IMPACTS...
BECOMING GUSTY DURING PEAK DIURNAL MIXING.
BAK
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR ILZ027>031-
036>038-040>043-047>053-061.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
322 PM CDT MON MAY 27 2013
.DISCUSSION...
1055 AM CDT
EARLY CHANGES MADE TO GOING FORECAST FOR THE REST OF TODAY INCLUDE
CUTTING DOWN POPS FOR MUCH OF THE NORTHERN FORECAST AREA THROUGH
AT LEAST EARLY AFTERNOON. ALSO ADJUSTED TEMPERATURES DOWN THE MOST
OVER THIS AREA AS THE COOL MEMORIAL DAY WEEKEND CONTINUES RIGHT
THROUGH THE HOLIDAY.
THE BROAD WARM AIR ADVECTION PATTERN CONTINUES OVER THE AREA
NORTH OF THE SURFACE STATIONARY BOUNDARY WHICH IS DRAPED ACROSS
FAR SOUTHERN IA INTO THE MID-SECTION OF IL. A REMNANT MCV AS SEEN
ON VISIBLE SATELLITE AND RADAR IMAGERY IS MOVING NORTHEAST INTO
NORTHWEST IN LATE THIS MORNING AND IS STARVED OF INSTABILITY...SO
JUST SOME SCATTERED ARCS OF SHOWERS HAVE BEEN SEEN WITH THIS.
SUPPRESSION WEST OF THIS HAS BEEN KEEPING MUCH OF THE NORTHERN HALF
OF THE CWA MAINLY DRY THIS MORNING AND LIMITING THE EASTWARD
PROGRESSION OF THE NEXT AREA OF SHOWERS AND CONVECTION FROM IA.
OBSERVATIONAL TRENDS SUPPORT HIGH RES GUIDANCE SOLUTIONS THAT TAKE
THE MCS IN NORTHEAST MO EASTWARD ACROSS CENTRAL/SOUTH CENTRAL IL
WHICH SHOULD KEEP THE SURFACE FRONT TO THE SOUTH. SO ALL IN ALL
THERE MAY BE LITTLE IN THE WAY OF PRECIP THROUGH MID-AFTERNOON
BESIDES SOME WIDELY SCATTERED SHOWERS OR SPRINKLES. BY LATE
AFTERNOON...THE INFLUENCE OF THE SHORT WAVE IN IA AND MORE FOCUSED
WARM AIR ADVECTION IS FORECAST TO MOVE OVER THE AREA. HOWEVER
LIMITED MOISTURE TRANSPORT RETURN PRIOR TO SUNSET MAY STILL KEEP
MUCH OF THE SHOWER COVERAGE SCATTERED AND MAINLY THUNDER-FREE.
THE EAST WIND NORTH OF THE BOUNDARY ALONG WITH LOW
CIGS...PRIMARILY ALONG AND NORTH OF THE I-88 CORRIDOR...WILL KEEP
TEMPERATURES FROM RECOVERING MUCH. HAVE LOWERED MAX TEMPS QUITE A
BIT TOWARD THE RAP SOLUTION. SOME LOCATIONS ARE LIKELY ONLY TO
CLIMB A COUPLE DEGREES MORE...ESPECIALLY IN LAKE COUNTY IL.
MTF
//PREV DISCUSSION...
318 AM CDT
THE UNSETTLED WEATHER WILL CONTINUE FOR THE NEXT SEVERAL
DAYS...WHICH WILL BE MARKED BY PERIODS OF SHOWERS AND THUNDERSTORMS
AS WELL AS THE RETURN OF MORE SUMMER-LIKE TEMPERATURES.
FOR THE REMAINDER OF THE NIGHT AND INTO THE EARLY MORNING
HOURS...THE FOCUS WILL REMAIN ON THE ONGOING SHOWERS AND
THUNDERSTORMS OVER THE SOUTHERN PORTIONS OF THE CWA. AS OF 3AM
CDT...MUCH OF THE PCPN HAS MOVED OUT OF LIVINGSTON AND FORD COUNTIES
AND IS DIMINISHING OVER IROQUOIS COUNTY. BENTON/JASPER/NEWTON
COUNTIES SHOULD SEE MODERATE TO OCNLY HEAVY PCPN WITH EMBEDDED
THUNDER FOR A FEW MORE HOURS...BUT SHOULD BE WINDING DOWN BY
DAYBREAK. THIS LINE OF HEAVY RAIN IS ALONG THE ELEVATED WARM
FRONT...WITH THE SFC WARM FRONT STILL WELL TO THE SOUTH...FROM NRN
MO TO SRN IL/IN. LATEST RADAR ESTIMATES INDICATE THAT SWATH OF 2-4
INCHES HAS FALLEN GENERALLY ALONG A LINE FROM...PONTIAC TO WATSEKA.
THESE PCPN SHOULD EXTEND EAST TOWARD REMINGTON BEFORE ALL IS SAID
AND DONE. RADAR ESTIMATES AS HIGH AS 5 INCHES ARE INDICATED
IN NORTHWESTERN LIVINGSTON COUNTY...NEAR CORNELL AND LONG POINT.
UNFORTUNATELY...THERE IS STILL A FAIR AMOUNT OF UNCERTAINTY IN THE
MEMORIAL DAY FORECAST AS THE AREA MAY YET BE IMPACTED BY BOUNDARIES
SET OUT BY THE STRONG CONVECTIVE CLUSTERS OVER THE MISSOURI VALLEY.
THE GENERAL TREND FOR THE DAY WILL START OUT WITH SOME SCT SHOWERS
OVER THE NORTHERN PORTIONS OF THE CWA...TOWARD THE WISCONSIN BORDER
AND SOME LINGERING RAIN TO THE SOUTH. THERE WILL LIKELY BE AT LEAST
SOME PERIODS OF DRY WEATHER OVER THE AREA...BUT WITH THE FREQUENTLY
DISCUSSED WARM FRONT SLOWLY MAKING ITS WAY NORTHWARD AND A SERIES OF
SHORT WAVES RIPPLING THROUGH THE DEAMPLIFYING MID LEVEL FLOW OVER THE
AREA...PERIODS OF SHOWERS AND THUNDERSTORMS ARE LIKELY THROUGH THE
DAY AND INTO TONIGHT. WHILE THE CHANCES FOR SEVERE WEATHER ARE
LOW...ANY THUNDERSTORMS THAT DO FORM CAN MAKE OUTDOOR ACTIVITIES
HAZARDOUS. ALSO...THE ENVIRONMENT HAS BEEN PRIMED WITH INCREASING
AMOUNTS OF DEEP LAYER MOISTURE...SO LOCALLY HEAVY RAINFALL WILL BE
POSSIBLE AS WELL. THE ONE POSITIVE NOTE THAT CAN BE MENTIONED FOR
TODAY IS THE TEMPERATURE TREND. WHILE SKIES WILL LIKELY BE CLOUDY
FOR MUCH OF THE DAY...GRADUALLY BUILDING HEIGHTS ALOFT WILL ALLOW
FOR TEMPERATURES A LITTLE HIGHER THAN RECENT DAYS...WITH HIGHS
RANGING FROM AROUND 60F ALONG THE NORTHERN ILLINOIS SHORE OF LAKE
MICHIGAN...TO THE MIDDLE 70S OVER THE SOUTHWESTERN PORTIONS OF THE
CWA...INCLUDING THE PONTIAC METRO AREA.
THE WARM FRONT IS EXPECTED TO LIFT NWD THROUGH NRN IL/IN OVERNIGHT
TONIGHT AND THEN CONTINUE NWD INTO WISCONSIN ON TUESDAY. THIS WILL
INITIATE THE EXPECTED WARMING TREND IN EARNEST...WITH SOUTHWESTERLY
FLOW SETTING UP IN THE LOWER LEVELS...DRAWING WARMER/MOISTER AIR
INTO THE REGION...AS UPPER RIDGING BEGINS TO BUILD FROM THE SERN
CONUS THROUGH THE UPPER MISSISSIPPI VALLEY. THIS COMBINATION WILL
BRING TEMPERATURES WELL INTO THE 80S...BUT WILL ALSO BRING DEW POINTS
IN THE MIDDLE TO UPPER 60S. THE TEMPERATURE AND DEW POINT TREND WILL
BE ON THE INCREASE THROUGH WEDNESDAY AND THURSDAY AS WELL...WITH
DEW POINTS APPROACHING 70F OVER MUCH OF THE AREA AND TEMPERATURES
REACHING INTO THE MIDDLE 80S...WITH SOME AREAS POSSIBLY REACHING THE
UPPER 80S. THE STRONG SOUTHWESTERLY FLOW WILL OVERCOME ANY LAKE
INFLUENCE AND THE WARMER CONDITIONS WILL BE ABLE TO PENETRATE UP TO
THE LAKE FRONT. WITH UPPER TROUGHING DEVELOPING OVER THE WRN
CONUS...SWLY FLOW WILL SET UP ALOFT AS WELL...WITH THE MODELS
ADVERTISING A SERIES OF IMPULSES RIDING NEWD UP THE BACKSIDE OF THE
RIDGE. WHILE THE MODELS ARE...TYPICALLY...INDICATING TIMING AND
STRENGTH DIFFERENCES TO THE INDIVIDUAL IMPULSES...THE SIGNAL IS
CLEAR THAT THESE WILL BRING ADDITIONAL PERIODS OF SHOWERS AND
THUNDERSTORMS. WITH DEEP LAYER MOISTURE STILL ON THE
INCREASE...WITH PWATS EXPECTED TO BE 1.5-2.0 INCHES THROUGH THE
PERIOD...LOCALLY HEAVY RAINFALL WILL BE A POSSIBILITY.
THE WARM...HUMID...UNSETTLED WEATHER WILL CONTINUE THROUGH FRIDAY.
BY SATURDAY...THE DEEPENING UPPER TROUGH WILL CLOSE OFF INTO A
LARGE...SPRAWLING UPPER LOW AND EVENTUALLY PUSH A COLD FRONT THROUGH
THE REGION. THE LATEST RUNS OF THE GFS/ECMWF ARE INDICATING THAT
THIS NEXT COLD FRONT SHOULD PUSH THROUGH THE AREA ON SATURDAY.
SINCE THIS IS A MODIFIED PACIFIC SYSTEM RATHER THAN A POLAR SYSTEM
DROPPING OUT OF CANADA...TEMPERATURES ARE ONLY EXPECTED TO DROP BACK
INTO THE 70S FOR NEXT WEEKEND.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* CIGS WILL HOVER IN THE LOW END MVFR...POSSIBLY SLIGHT
IMPROVEMENT LATER.
* EAST WINDS WILL PERSIST...WITH SOME TURNING TO THE SOUTHEAST
LATE THIS EVE. SPEEDS GENERALLY ARND 10-12KT...OCCASIONAL GUSTS
IN THE MID/UPR TEENS.
* SHRA/TSRA MAY BEGIN TO DEVELOP AFT 00Z THRU OVERNIGHT.
BEACHLER
//DISCUSSION...UPDATED 20Z...
CIGS HAVE BEGUN TO IMPROVE TO LOW END MVFR CONDITIONS ACROSS
NORTHEAST IL/NORTHWEST IN AIRFIELDS. SCT SHRA/TSRA HAVE ALSO
DEVELOPED THIS AFTERNOON ACROSS CENTRAL/SOUTHERN IL. THE WARM
FRONTAL BOUNDARY CONTINUES TO RESIDE ACROSS CENTRAL IL...AND IS
EXPECTED TO SLOWLY LIFT BACK TO THE NORTH THIS EVENING.
PREVIOUS DISCUSSION UPDATED 18Z...
SIGNIFICANT CHALLENGES CONTINUE WITH THIS AFTN FORECAST PACKAGE.
MAIN CONCERN IS ON TIMING OF IMPROVING CIGS FROM IFR CONDITIONS TO
LOW END MVFR. LATEST OBS HAVE SHOWN A MINOR BUMP TO BORDERLINE
IFR/MVFR CIGS...AND WITH HEATING FROM ALOFT SHUD SEE CIGS STAY AT
CURRENT LEVELS OF ARND 1000FT AGL...THEN SLOW IMPROVEMENT TO ARND
1500FT AGL BY LATE THIS AFTN. WITH THE CONVECTION WELL SOUTHWEST
OF THE NORTHERN IL/NORTHWEST IN AIRFIELDS...THE BOUNDARY HAS
PUSHED FURTHER SOUTH. THIS AS A RESULT WILL KEEP EASTERLY WINDS
THRU EARLY THIS EVE...THEN THE BOUNDARY WILL BEGIN TO LIFT BACK TO
THE NORTH. AS THIS OCCURS...THE WIND DIRECTIONS WILL BEGIN TO TURN
SOUTHEASTERLY ALTHOUGH VERY SLOWLY WITH THE LACK OF A PUSH TO
BRING WINDS MORE SOUTHERLY UNTIL TUE LATE MORNING. CIGS WILL
CONTINUE TO HOVER ARND MVFR CONDS...POSSIBLY BRIEFLY GOING TO VFR
LATE THIS EVENING...HOWEVER THIS ALL HINGES UPON THE
COVERAGE/INTENSITY/TIMING OF CONVECTION.
THE OTHER CHALLENGE FOR THIS AFTN/EVE IS ON THE TIMING/COVERAGE OF
SHRA/TSRA. GUIDANCE HAS BACKED OFF ON THE ARRIVAL OF ANY
CONVECTION UNTIL CLOSER TO 00Z...POSSIBLY EVEN LATER. AS A RESULT
HAVE PUSHED BACK THE ARRIVAL OF CONVECTION. ALSO IT APPEARS THAT A
COMPLEX OF THUNDERSTORMS WILL DEVELOP TO THE WEST IN IOWA
OVERNIGHT...THEN SLIDE EAST. THEN IT APPEARS A LULL IN THE
SHRA/TSRA WILL OCCUR SOMETIME ARND DAYBREAK TUE THRU MID-
MORNING...BEFORE THE SECOND CONVECTIVE WAVE DEVELOPS AND ARRIVES.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM CONFIDENCE IN LOW END MVFR CIGS. LOW CONFIDENCE IN
TIMING OF CIGS PUSHING HIGHER INTO HIGHER END MVFR.
* MEDIUM CONFIDENCE IN WIND FORECAST.
* LOW CONFIDENCE IN OVERALL SHRA/TSRA TIMING...MEDIUM CONFIDENCE
THAT THE BETTER CHANCES WOULD NOT BE UNTIL LATER THIS EVENING AND
BEYOND.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT THROUGH SATURDAY...MAINLY VFR...PERIODIC SHRA/TSRA
ESPECIALLY TUESDAY NIGHT AND FRIDAY. BREEZY SOUTH WINDS WEDNESDAY
THROUGH SATURDAY.
MDB
&&
.MARINE...
320 PM CDT
AS HIGH PRESSURE MOVES EAST OVER QUEBEC AND NEW ENGLAND AND OFF THE
ATLANTIC COAST TONIGHT A BROAD AREA OF LOW PRESSURE CENTERED IN THE
CENTRAL HIGH PLAINS WILL MOVE NORTHEAST TO NEAR THE EASTERN DAKOTAS
BY MORNING. THIS LOW CONTINUES NORTHEASTWARD ACROSS THE UPPER
MIDWEST TO WESTERN ONTARIO DURING TUESDAY...LIFTING A WARM FRONT
NORTHWARD DURING THE DAY WHICH WILL PASS NORTH OF THE LAKE BY EARLY
TUESDAY EVENING.
NORTH OF THE WARM FRONT TUESDAY THERE WILL BE A MODERATE TO FRESH
BREEZE OUT OF THE EAST TO SOUTHEAST WHILE SOUTH OF THE WARM FRONT
THERE WILL FRESH TO STRONG SOUTH AND SOUTHWEST BREEZES.
WHILE THERE WILL BE A PROLONGED PERIOD OF SOUTH TO SOUTHWEST WINDS
FOLLOWING THE WARM FRONT BUT DUE TO THE STABLE SETUP OF WARM AIR
OVER COOL WATER WIND SPEEDS NEAR AND AT THE LAKE SURFACE WILL BE
MUCH REDUCED SO WAVE GROWTH WILL BE LIMITED.
THE SOUTH AND SOUTHWEST WINDS WILL PERSIST UNTIL LATE
SATURDAY/SATURDAY NIGHT WHEN A COLD FRONT MOVES EAST ACROSS THE
LAKE SHIFTING WINDS TO OUT OF THE WEST AND NORTHWEST. THIS COLD
FRONT WILL TRAIL FROM LOW PRESSURE THAT MOVES EAST-NORTHEAST
THROUGH THE NORTHERN GREAT LAKES TO SOUTHERN QUEBEC.
TRS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ010-ILZ019-ILZ021-ILZ023-ILZ032-ILZ033-
ILZ039...7 PM MONDAY TO NOON TUESDAY.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
302 PM CDT MON MAY 27 2013
.DISCUSSION...
1055 AM CDT
EARLY CHANGES MADE TO GOING FORECAST FOR THE REST OF TODAY INCLUDE
CUTTING DOWN POPS FOR MUCH OF THE NORTHERN FORECAST AREA THROUGH
AT LEAST EARLY AFTERNOON. ALSO ADJUSTED TEMPERATURES DOWN THE MOST
OVER THIS AREA AS THE COOL MEMORIAL DAY WEEKEND CONTINUES RIGHT
THROUGH THE HOLIDAY.
THE BROAD WARM AIR ADVECTION PATTERN CONTINUES OVER THE AREA
NORTH OF THE SURFACE STATIONARY BOUNDARY WHICH IS DRAPED ACROSS
FAR SOUTHERN IA INTO THE MID-SECTION OF IL. A REMNANT MCV AS SEEN
ON VISIBLE SATELLITE AND RADAR IMAGERY IS MOVING NORTHEAST INTO
NORTHWEST IN LATE THIS MORNING AND IS STARVED OF INSTABILITY...SO
JUST SOME SCATTERED ARCS OF SHOWERS HAVE BEEN SEEN WITH THIS.
SUPPRESSION WEST OF THIS HAS BEEN KEEPING MUCH OF THE NORTHERN HALF
OF THE CWA MAINLY DRY THIS MORNING AND LIMITING THE EASTWARD
PROGRESSION OF THE NEXT AREA OF SHOWERS AND CONVECTION FROM IA.
OBSERVATIONAL TRENDS SUPPORT HIGH RES GUIDANCE SOLUTIONS THAT TAKE
THE MCS IN NORTHEAST MO EASTWARD ACROSS CENTRAL/SOUTH CENTRAL IL
WHICH SHOULD KEEP THE SURFACE FRONT TO THE SOUTH. SO ALL IN ALL
THERE MAY BE LITTLE IN THE WAY OF PRECIP THROUGH MID-AFTERNOON
BESIDES SOME WIDELY SCATTERED SHOWERS OR SPRINKLES. BY LATE
AFTERNOON...THE INFLUENCE OF THE SHORT WAVE IN IA AND MORE FOCUSED
WARM AIR ADVECTION IS FORECAST TO MOVE OVER THE AREA. HOWEVER
LIMITED MOISTURE TRANSPORT RETURN PRIOR TO SUNSET MAY STILL KEEP
MUCH OF THE SHOWER COVERAGE SCATTERED AND MAINLY THUNDER-FREE.
THE EAST WIND NORTH OF THE BOUNDARY ALONG WITH LOW
CIGS...PRIMARILY ALONG AND NORTH OF THE I-88 CORRIDOR...WILL KEEP
TEMPERATURES FROM RECOVERING MUCH. HAVE LOWERED MAX TEMPS QUITE A
BIT TOWARD THE RAP SOLUTION. SOME LOCATIONS ARE LIKELY ONLY TO
CLIMB A COUPLE DEGREES MORE...ESPECIALLY IN LAKE COUNTY IL.
MTF
//PREV DISCUSSION...
318 AM CDT
THE UNSETTLED WEATHER WILL CONTINUE FOR THE NEXT SEVERAL
DAYS...WHICH WILL BE MARKED BY PERIODS OF SHOWERS AND THUNDERSTORMS
AS WELL AS THE RETURN OF MORE SUMMER-LIKE TEMPERATURES.
FOR THE REMAINDER OF THE NIGHT AND INTO THE EARLY MORNING
HOURS...THE FOCUS WILL REMAIN ON THE ONGOING SHOWERS AND
THUNDERSTORMS OVER THE SOUTHERN PORTIONS OF THE CWA. AS OF 3AM
CDT...MUCH OF THE PCPN HAS MOVED OUT OF LIVINGSTON AND FORD COUNTIES
AND IS DIMINISHING OVER IROQUOIS COUNTY. BENTON/JASPER/NEWTON
COUNTIES SHOULD SEE MODERATE TO OCNLY HEAVY PCPN WITH EMBEDDED
THUNDER FOR A FEW MORE HOURS...BUT SHOULD BE WINDING DOWN BY
DAYBREAK. THIS LINE OF HEAVY RAIN IS ALONG THE ELEVATED WARM
FRONT...WITH THE SFC WARM FRONT STILL WELL TO THE SOUTH...FROM NRN
MO TO SRN IL/IN. LATEST RADAR ESTIMATES INDICATE THAT SWATH OF 2-4
INCHES HAS FALLEN GENERALLY ALONG A LINE FROM...PONTIAC TO WATSEKA.
THESE PCPN SHOULD EXTEND EAST TOWARD REMINGTON BEFORE ALL IS SAID
AND DONE. RADAR ESTIMATES AS HIGH AS 5 INCHES ARE INDICATED
IN NORTHWESTERN LIVINGSTON COUNTY...NEAR CORNELL AND LONG POINT.
UNFORTUNATELY...THERE IS STILL A FAIR AMOUNT OF UNCERTAINTY IN THE
MEMORIAL DAY FORECAST AS THE AREA MAY YET BE IMPACTED BY BOUNDARIES
SET OUT BY THE STRONG CONVECTIVE CLUSTERS OVER THE MISSOURI VALLEY.
THE GENERAL TREND FOR THE DAY WILL START OUT WITH SOME SCT SHOWERS
OVER THE NORTHERN PORTIONS OF THE CWA...TOWARD THE WISCONSIN BORDER
AND SOME LINGERING RAIN TO THE SOUTH. THERE WILL LIKELY BE AT LEAST
SOME PERIODS OF DRY WEATHER OVER THE AREA...BUT WITH THE FREQUENTLY
DISCUSSED WARM FRONT SLOWLY MAKING ITS WAY NORTHWARD AND A SERIES OF
SHORT WAVES RIPPLING THROUGH THE DEAMPLIFYING MIDLEVEL FLOW OVER THE
AREA...PERIODS OF SHOWERS AND THUNDERSTORMS ARE LIKELY THROUGH THE
DAY AND INTO TONIGHT. WHILE THE CHANCES FOR SEVERE WEATHER ARE
LOW...ANY THUNDERSTORMS THAT DO FORM CAN MAKE OUTDOOR ACTIVITIES
HAZARDOUS. ALSO...THE ENVIRONMENT HAS BEEN PRIMED WITH INCREASING
AMOUNTS OF DEEP LAYER MOISTURE...SO LOCALLY HEAVY RAINFALL WILL BE
POSSIBLE AS WELL. THE ONE POSITIVE NOTE THAT CAN BE MENTIONED FOR
TODAY IS THE TEMPERATURE TREND. WHILE SKIES WILL LIKELY BE CLOUDY
FOR MUCH OF THE DAY...GRADUALLY BUILDING HEIGHTS ALOFT WILL ALLOW
FOR TEMPERATURES A LITTLE HIGHER THAN RECENT DAYS...WITH HIGHS
RANGING FROM AROUND 60F ALONG THE NORTHERN ILLINOIS SHORE OF LAKE
MICHIGAN...TO THE MIDDLE 70S OVER THE SOUTHWESTERN PORTIONS OF THE
CWA...INCLUDING THE PONTIAC METRO AREA.
THE WARM FRONT IS EXPECTED TO LIFT NWD THROUGH NRN IL/IN OVERNIGHT
TONIGHT AND THEN CONTINUE NWD INTO WISCONSIN ON TUESDAY. THIS WILL
INITIATE THE EXPECTED WARMING TREND IN EARNEST...WITH SOUTHWESTERLY
FLOW SETTING UP IN THE LOWER LEVELS...DRAWING WARMER/MOISTER AIR
INTO THE REGION...AS UPPER RIDGING BEGINS TO BUILD FROM THE SERN
CONUS THROUGH THE UPPER MISSISSIPPI VALLEY. THIS COMBINATION WILL
BRING TEMPERATURES WELL INTO THE 80S...BUT WILL ALSO BRING DEWPOINTS
IN THE MIDDLE TO UPPER 60S. THE TEMPERATURE AND DEWPOINT TREND WILL
BE ON THE INCREASE THROUGH WEDNESDAY AND THURSDAY AS WELL...WITH
DEWPOINTS APPROACHING 70F OVER MUCH OF THE AREA AND TEMPERATURES
REACHING INTO THE MIDDLE 80S...WITH SOME AREAS POSSIBLY REACHING THE
UPPER 80S. THE STRONG SOUTHWESTERLY FLOW WILL OVERCOME ANY LAKE
INFLUENCE AND THE WARMER CONDITIONS WILL BE ABLE TO PENETRATE UP TO
THE LAKE FRONT. WITH UPPER TROUGHING DEVELOPING OVER THE WRN
CONUS...SWLY FLOW WILL SET UP ALOFT AS WELL...WITH THE MODELS
ADVERTISING A SERIES OF IMPULSES RIDING NEWD UP THE BACKSIDE OF THE
RIDGE. WHILE THE MODELS ARE...TYPICALLY...INDICATING TIMING AND
STRENGTH DIFFERENCES TO THE INDIVIDUAL IMPULSES...THE SIGNAL IS
CLEAR THAT THESE WILL BRING ADDITIONAL PERIODS OF SHOWERS AND
THUNDERSTORMS. WITH DEEP LAYER MOISTURE STILL ON THE
INCREASE...WITH PWATS EXPECTED TO BE 1.5-2.0 INCHES THROUGH THE
PERIOD...LOCALLY HEAVY RAINFALL WILL BE A POSSIBILITY.
THE WARM...HUMID...UNSETTLED WEATHER WILL CONTINUE THROUGH FRIDAY.
BY SATURDAY...THE DEEPENING UPPER TROUGH WILL CLOSE OFF INTO A
LARGE...SPRAWLING UPPER LOW AND EVENTUALLY PUSH A COLD FRONT THROUGH
THE REGION. THE LATEST RUNS OF THE GFS/ECMWF ARE INDICATING THAT
THIS NEXT COLD FRONT SHOULD PUSH THROUGH THE AREA ON SATURDAY.
SINCE THIS IS A MODIFIED PACIFIC SYSTEM RATHER THAN A POLAR SYSTEM
DROPPING OUT OF CANADA...TEMPERATURES ARE ONLY EXPECTED TO DROP BACK
INTO THE 70S FOR NEXT WEEKEND.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* CIGS WILL HOVER IN THE LOW END MVFR...POSSIBLY SLIGHT
IMPROVEMENT LATER.
* EAST WINDS WILL PERSIST...WITH SOME TURNING TO THE SOUTHEAST
LATE THIS EVE. SPEEDS GENERALLY ARND 10-12KT...OCCASIONAL GUSTS
IN THE MID/UPR TEENS.
* SHRA/TSRA MAY BEGIN TO DEVELOP AFT 00Z THRU OVERNIGHT.
BEACHLER
//DISCUSSION...UPDATED 20Z...
CIGS HAVE BEGUN TO IMPROVE TO LOW END MVFR CONDITIONS ACROSS
NORTHEAST IL/NORTHWEST IN AIRFIELDS. SCT SHRA/TSRA HAVE ALSO
DEVELOPED THIS AFTERNOON ACROSS CENTRAL/SOUTHERN IL. THE WARM
FRONTAL BOUNDARY CONTINUES TO RESIDE ACROSS CENTRAL IL...AND IS
EXPECTED TO SLOWLY LIFT BACK TO THE NORTH THIS EVENING.
PREVIOUS DISCUSSION UPDATED 18Z...
SIGNIFICANT CHALLENGES CONTINUE WITH THIS AFTN FORECAST PAKCAGE.
MAIN CONCERN IS ON TIMING OF IMPROVING CIGS FROM IFR CONDITIONS TO
LOW END MVFR. LATEST OBS HAVE SHOWN A MINOR BUMP TO BORDERLINE
IFR/MVFR CIGS...AND WITH HEATING FROM ALOFT SHUD SEE CIGS STAY AT
CURRENT LEVELS OF ARND 1000FT AGL...THEN SLOW IMPROVEMENT TO ARND
1500FT AGL BY LATE THIS AFTN. WITH THE CONVECTION WELL SOUTHWEST
OF THE NORTHERN IL/NORTHWEST IN AIRFIELDS...THE BOUNDARY HAS
PUSHED FURTHER SOUTH. THIS AS A RESULT WILL KEEP EASTERLY WINDS
THRU EARLY THIS EVE...THEN THE BOUNDARY WILL BEGIN TO LIFT BACK TO
THE NORTH. AS THIS OCCURS...THE WIND DIRECTIONS WILL BEGIN TO TURN
SOUTHEASTERLY ALTHOUGH VERY SLOWLY WITH THE LACK OF A PUSH TO
BRING WINDS MORE SOUTHERLY UNTIL TUE LATE MORNING. CIGS WILL
CONTINUE TO HOVER ARND MVFR CONDS...POSSIBLY BRIEFLY GOING TO VFR
LATE THIS EVENING...HOWEVER THIS ALL HINGES UPON THE
COVERAGE/INTENSITY/TIMING OF CONVECTION.
THE OTHER CHALLENGE FOR THIS AFTN/EVE IS ON THE TIMING/COVERAGE OF
SHRA/TSRA. GUIDANCE HAS BACKED OFF ON THE ARRIVAL OF ANY
CONVECTION UNTIL CLOSER TO 00Z...POSSIBLY EVEN LATER. AS A RESULT
HAVE PUSHED BACK THE ARRIVAL OF CONVECTION. ALSO IT APPEARS THAT A
COMPLEX OF THUNDERSTORMS WILL DEVELOP TO THE WEST IN IOWA
OVERNIGHT...THEN SLIDE EAST. THEN IT APPEARS A LULL IN THE
SHRA/TSRA WILL OCCUR SOMETIME ARND DAYBREAK TUE THRU MID-
MORNING...BEFORE THE SECOND CONVECTIVE WAVE DEVELOPS AND ARRIVES.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM CONFIDENCE IN LOW END MVFR CIGS. LOW CONFIDENCE IN
TIMING OF CIGS PUSHING HIGHER INTO HIGHER END MVFR.
* MEDIUM CONFIDENCE IN WIND FORECAST.
* LOW CONFIDENCE IN OVERALL SHRA/TSRA TIMING...MEDIUM CONFIDENCE
THAT THE BETTER CHANCES WOULD NOT BE UNTIL LATER THIS EVENING AND
BEYOND.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT THROUGH SATURDAY...MAINLY VFR...PERIODIC SHRA/TSRA
ESPECIALLY TUESDAY NIGHT AND FRIDAY. BREEZY SOUTH WINDS WEDNESDAY
THROUGH SATURDAY.
MDB
&&
.MARINE...
314 AM CDT
HIGH PRESSURE IS MOVING OFF TO THE EAST AND IS NOW POSITIONED FROM
HUDSON BAY DOWN ACROSS LAKE ERIE AND TO THE MID ATLANTIC COAST. LOW
PRESSURE CONTINUES TO DEVELOP ACROSS THE HIGH PLAINS WITH ONE LOW
CENTER OVER SOUTHEAST COLORADO AND FAR WESTERN KANSAS. THE PRESSURE
GRADIENT WILL TIGHTEN TODAY WITH LAKE MICHIGAN BETWEEN THESE TWO
SYSTEMS. SOUTHEAST WINDS WILL INCREASE AS A RESULT THEN TURN SOUTH
AND SOUTHWEST TUESDAY. SOUTH TO SOUTHWEST WINDS WILL THEN CONTINUE
THROUGH THE REST OF THE WEEK AS THE HIGH REMAINS TO THE EAST AND
SEVERAL LOW PRESSURE SYSTEMS MOVE NORTHWEST OF THE LAKE. WIND SPEEDS
WILL GENERALLY BE IN THE 15 TO 25 KT RANGE WITH PERIODIC INCREASES
TO THE HIGHER END OF THAT RANGE...WITH 30 KT POSSIBLE AT TIMES...BUT
THERE WILL ALSO BE PERIODS IN THE 10 TO 20 OR 15-20 KT RANGE. WARMER
AIR MOVING IN WILL HELP LIMIT THE GUSTS...ESPECIALLY OVER THE OPEN
WATERS BUT SOME OF THE TALLER PILOT HOUSES AND SHORE BASED OB SITES
COULD SEE GUSTS JUST ABOVE 30 KT AT TIMES AS THEY WOULD BE ABOVE THE
STABLE MARINE LAYER. NEARSHORE AREAS WILL FLIRT WITH SMALL CRAFT
ADVISORY CRITERIA AT TIMES AS WELL BUT AT THIS POINT WILL KEEP WINDS
AT 15 TO 25 KT WITH PERIODS OF 20-25 KT LOOKING BRIEF AND DIFFICULT
TO PIN DOWN.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
106 PM CDT MON MAY 27 2013
.DISCUSSION...
1055 AM CDT
EARLY CHANGES MADE TO GOING FORECAST FOR THE REST OF TODAY INCLUDE
CUTTING DOWN POPS FOR MUCH OF THE NORTHERN FORECAST AREA THROUGH
AT LEAST EARLY AFTERNOON. ALSO ADJUSTED TEMPERATURES DOWN THE MOST
OVER THIS AREA AS THE COOL MEMORIAL DAY WEEKEND CONTINUES RIGHT
THROUGH THE HOLIDAY.
THE BROAD WARM AIR ADVECTION PATTERN CONTINUES OVER THE AREA
NORTH OF THE SURFACE STATIONARY BOUNDARY WHICH IS DRAPED ACROSS
FAR SOUTHERN IA INTO THE MID-SECTION OF IL. A REMNANT MCV AS SEEN
ON VISIBLE SATELLITE AND RADAR IMAGERY IS MOVING NORTHEAST INTO
NORTHWEST IN LATE THIS MORNING AND IS STARVED OF INSTABILITY...SO
JUST SOME SCATTERED ARCS OF SHOWERS HAVE BEEN SEEN WITH THIS.
SUPPRESSION WEST OF THIS HAS BEEN KEEPING MUCH OF THE NORTHERN HALF
OF THE CWA MAINLY DRY THIS MORNING AND LIMITING THE EASTWARD
PROGRESSION OF THE NEXT AREA OF SHOWERS AND CONVECTION FROM IA.
OBSERVATIONAL TRENDS SUPPORT HIGH RES GUIDANCE SOLUTIONS THAT TAKE
THE MCS IN NORTHEAST MO EASTWARD ACROSS CENTRAL/SOUTH CENTRAL IL
WHICH SHOULD KEEP THE SURFACE FRONT TO THE SOUTH. SO ALL IN ALL
THERE MAY BE LITTLE IN THE WAY OF PRECIP THROUGH MID-AFTERNOON
BESIDES SOME WIDELY SCATTERED SHOWERS OR SPRINKLES. BY LATE
AFTERNOON...THE INFLUENCE OF THE SHORT WAVE IN IA AND MORE FOCUSED
WARM AIR ADVECTION IS FORECAST TO MOVE OVER THE AREA. HOWEVER
LIMITED MOISTURE TRANSPORT RETURN PRIOR TO SUNSET MAY STILL KEEP
MUCH OF THE SHOWER COVERAGE SCATTERED AND MAINLY THUNDER-FREE.
THE EAST WIND NORTH OF THE BOUNDARY ALONG WITH LOW
CIGS...PRIMARILY ALONG AND NORTH OF THE I-88 CORRIDOR...WILL KEEP
TEMPERATURES FROM RECOVERING MUCH. HAVE LOWERED MAX TEMPS QUITE A
BIT TOWARD THE RAP SOLUTION. SOME LOCATIONS ARE LIKELY ONLY TO
CLIMB A COUPLE DEGREES MORE...ESPECIALLY IN LAKE COUNTY IL.
MTF
//PREV DISCUSSION...
318 AM CDT
THE UNSETTLED WEATHER WILL CONTINUE FOR THE NEXT SEVERAL
DAYS...WHICH WILL BE MARKED BY PERIODS OF SHOWERS AND THUNDERSTORMS
AS WELL AS THE RETURN OF MORE SUMMER-LIKE TEMPERATURES.
FOR THE REMAINDER OF THE NIGHT AND INTO THE EARLY MORNING
HOURS...THE FOCUS WILL REMAIN ON THE ONGOING SHOWERS AND
THUNDERSTORMS OVER THE SOUTHERN PORTIONS OF THE CWA. AS OF 3AM
CDT...MUCH OF THE PCPN HAS MOVED OUT OF LIVINGSTON AND FORD COUNTIES
AND IS DIMINISHING OVER IROQUOIS COUNTY. BENTON/JASPER/NEWTON
COUNTIES SHOULD SEE MODERATE TO OCNLY HEAVY PCPN WITH EMBEDDED
THUNDER FOR A FEW MORE HOURS...BUT SHOULD BE WINDING DOWN BY
DAYBREAK. THIS LINE OF HEAVY RAIN IS ALONG THE ELEVATED WARM
FRONT...WITH THE SFC WARM FRONT STILL WELL TO THE SOUTH...FROM NRN
MO TO SRN IL/IN. LATEST RADAR ESTIMATES INDICATE THAT SWATH OF 2-4
INCHES HAS FALLEN GENERALLY ALONG A LINE FROM...PONTIAC TO WATSEKA.
THESE PCPN SHOULD EXTEND EAST TOWARD REMINGTON BEFORE ALL IS SAID
AND DONE. RADAR ESTIMATES AS HIGH AS 5 INCHES ARE INDICATED
IN NORTHWESTERN LIVINGSTON COUNTY...NEAR CORNELL AND LONG POINT.
UNFORTUNATELY...THERE IS STILL A FAIR AMOUNT OF UNCERTAINTY IN THE
MEMORIAL DAY FORECAST AS THE AREA MAY YET BE IMPACTED BY BOUNDARIES
SET OUT BY THE STRONG CONVECTIVE CLUSTERS OVER THE MISSOURI VALLEY.
THE GENERAL TREND FOR THE DAY WILL START OUT WITH SOME SCT SHOWERS
OVER THE NORTHERN PORTIONS OF THE CWA...TOWARD THE WISCONSIN BORDER
AND SOME LINGERING RAIN TO THE SOUTH. THERE WILL LIKELY BE AT LEAST
SOME PERIODS OF DRY WEATHER OVER THE AREA...BUT WITH THE FREQUENTLY
DISCUSSED WARM FRONT SLOWLY MAKING ITS WAY NORTHWARD AND A SERIES OF
SHORT WAVES RIPPLING THROUGH THE DEAMPLIFYING MIDLEVEL FLOW OVER THE
AREA...PERIODS OF SHOWERS AND THUNDERSTORMS ARE LIKELY THROUGH THE
DAY AND INTO TONIGHT. WHILE THE CHANCES FOR SEVERE WEATHER ARE
LOW...ANY THUNDERSTORMS THAT DO FORM CAN MAKE OUTDOOR ACTIVITIES
HAZARDOUS. ALSO...THE ENVIRONMENT HAS BEEN PRIMED WITH INCREASING
AMOUNTS OF DEEP LAYER MOISTURE...SO LOCALLY HEAVY RAINFALL WILL BE
POSSIBLE AS WELL. THE ONE POSITIVE NOTE THAT CAN BE MENTIONED FOR
TODAY IS THE TEMPERATURE TREND. WHILE SKIES WILL LIKELY BE CLOUDY
FOR MUCH OF THE DAY...GRADUALLY BUILDING HEIGHTS ALOFT WILL ALLOW
FOR TEMPERATURES A LITTLE HIGHER THAN RECENT DAYS...WITH HIGHS
RANGING FROM AROUND 60F ALONG THE NORTHERN ILLINOIS SHORE OF LAKE
MICHIGAN...TO THE MIDDLE 70S OVER THE SOUTHWESTERN PORTIONS OF THE
CWA...INCLUDING THE PONTIAC METRO AREA.
THE WARM FRONT IS EXPECTED TO LIFT NWD THROUGH NRN IL/IN OVERNIGHT
TONIGHT AND THEN CONTINUE NWD INTO WISCONSIN ON TUESDAY. THIS WILL
INITIATE THE EXPECTED WARMING TREND IN EARNEST...WITH SOUTHWESTERLY
FLOW SETTING UP IN THE LOWER LEVELS...DRAWING WARMER/MOISTER AIR
INTO THE REGION...AS UPPER RIDGING BEGINS TO BUILD FROM THE SERN
CONUS THROUGH THE UPPER MISSISSIPPI VALLEY. THIS COMBINATION WILL
BRING TEMPERATURES WELL INTO THE 80S...BUT WILL ALSO BRING DEWPOINTS
IN THE MIDDLE TO UPPER 60S. THE TEMPERATURE AND DEWPOINT TREND WILL
BE ON THE INCREASE THROUGH WEDNESDAY AND THURSDAY AS WELL...WITH
DEWPOINTS APPROACHING 70F OVER MUCH OF THE AREA AND TEMPERATURES
REACHING INTO THE MIDDLE 80S...WITH SOME AREAS POSSIBLY REACHING THE
UPPER 80S. THE STRONG SOUTHWESTERLY FLOW WILL OVERCOME ANY LAKE
INFLUENCE AND THE WARMER CONDITIONS WILL BE ABLE TO PENETRATE UP TO
THE LAKE FRONT. WITH UPPER TROUGHING DEVELOPING OVER THE WRN
CONUS...SWLY FLOW WILL SET UP ALOFT AS WELL...WITH THE MODELS
ADVERTISING A SERIES OF IMPULSES RIDING NEWD UP THE BACKSIDE OF THE
RIDGE. WHILE THE MODELS ARE...TYPICALLY...INDICATING TIMING AND
STRENGTH DIFFERENCES TO THE INDIVIDUAL IMPULSES...THE SIGNAL IS
CLEAR THAT THESE WILL BRING ADDITIONAL PERIODS OF SHOWERS AND
THUNDERSTORMS. WITH DEEP LAYER MOISTURE STILL ON THE
INCREASE...WITH PWATS EXPECTED TO BE 1.5-2.0 INCHES THROUGH THE
PERIOD...LOCALLY HEAVY RAINFALL WILL BE A POSSIBILITY.
THE WARM...HUMID...UNSETTLED WEATHER WILL CONTINUE THROUGH FRIDAY.
BY SATURDAY...THE DEEPENING UPPER TROUGH WILL CLOSE OFF INTO A
LARGE...SPRAWLING UPPER LOW AND EVENTUALLY PUSH A COLD FRONT THROUGH
THE REGION. THE LATEST RUNS OF THE GFS/ECMWF ARE INDICATING THAT
THIS NEXT COLD FRONT SHOULD PUSH THROUGH THE AREA ON SATURDAY.
SINCE THIS IS A MODIFIED PACIFIC SYSTEM RATHER THAN A POLAR SYSTEM
DROPPING OUT OF CANADA...TEMPERATURES ARE ONLY EXPECTED TO DROP BACK
INTO THE 70S FOR NEXT WEEKEND.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* BORDERLINE IFR/MVFR CIGS...WILL IMPROVE TO MVFR LATE THIS AFTN.
* EAST WINDS WILL PERSIST...WITH SOME TURNING TO THE SOUTHEAST
LATE THIS EVE. SPEEDS GENERALLY ARND 10-12KT...OCCASIONAL GUSTS
IN THE MID/UPR TEENS.
* PATCHY DZ ENDING...SHRA/TSRA MAY BEGIN TO DEVELOP AFT 00Z THRU
OVERNIGHT.
BEACHLER
//DISCUSSION...UPDATED 18Z...
SIGNIFICANT CHALLENGES CONTINUE WITH THIS AFTN FORECAST PAKCAGE.
MAIN CONCERN IS ON TIMING OF IMPROVING CIGS FROM IFR CONDITIONS TO
LOW END MVFR. LATEST OBS HAVE SHOWN A MINOR BUMP TO BORDERLINE
IFR/MVFR CIGS...AND WITH HEATING FROM ALOFT SHUD SEE CIGS STAY AT
CURRENT LEVELS OF ARND 1000FT AGL...THEN SLOW IMPROVEMENT TO ARND
1500FT AGL BY LATE THIS AFTN. WITH THE CONVECTION WELL SOUTHWEST
OF THE NORTHERN IL/NORTHWEST IN AIRFIELDS...THE BOUNDARY HAS
PUSHED FURTHER SOUTH. THIS AS A RESULT WILL KEEP EASTERLY WINDS
THRU EARLY THIS EVE...THEN THE BOUNDARY WILL BEGIN TO LIFT BACK TO
THE NORTH. AS THIS OCCURS...THE WIND DIRECTIONS WILL BEGIN TO TURN
SOUTHEASTERLY ALTHOUGH VERY SLOWLY WITH THE LACK OF A PUSH TO
BRING WINDS MORE SOUTHERLY UNTIL TUE LATE MORNING. CIGS WILL
CONTINUE TO HOVER ARND MVFR CONDS...POSSIBLY BRIEFLY GOING TO VFR
LATE THIS EVENING...HOWEVER THIS ALL HINGES UPON THE
COVERAGE/INTENSITY/TIMING OF CONVECTION.
THE OTHER CHALLENGE FOR THIS AFTN/EVE IS ON THE TIMING/COVERAGE OF
SHRA/TSRA. GUIDANCE HAS BACKED OFF ON THE ARRIVAL OF ANY
CONVECTION UNTIL CLOSER TO 00Z...POSSIBLY EVEN LATER. AS A RESULT
HAVE PUSHED BACK THE ARRIVAL OF CONVECTION. ALSO IT APPEARS THAT A
COMPLEX OF THUNDERSTORMS WILL DEVELOP TO THE WEST IN IOWA
OVERNIGHT...THEN SLIDE EAST. THEN IT APPEARS A LULL IN THE
SHRA/TSRA WILL OCCUR SOMETIME ARND DAYBREAK TUE THRU MID-
MORNING...BEFORE THE SECOND CONVECTIVE WAVE DEVELOPS AND ARRIVES.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE IN CIGS PERSISTING AT BORDERLINE IFR/MVFR...LOW
CONFIDENCE IN TIMING OF PUSHING SOLIDLY INTO LOW END MVFR CIGS.
* HIGH CONFIDENCE IN WIND FORECAST.
* LOW CONFIDENCE IN OVERALL SHRA/TSRA TIMING...MEDIUM CONFIDENCE
THAT THE BETTER CHANCES WOULD NOT BE UNTIL LATER THIS EVENING AND
BEYOND.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT THROUGH SATURDAY...MAINLY VFR...PERIODIC SHRA/TSRA
ESPECIALLY TUESDAY NIGHT AND FRIDAY. BREEZY SOUTH WINDS WEDNESDAY
THROUGH SATURDAY.
MDB
&&
.MARINE...
314 AM CDT
HIGH PRESSURE IS MOVING OFF TO THE EAST AND IS NOW POSITIONED FROM
HUDSON BAY DOWN ACROSS LAKE ERIE AND TO THE MID ATLANTIC COAST. LOW
PRESSURE CONTINUES TO DEVELOP ACROSS THE HIGH PLAINS WITH ONE LOW
CENTER OVER SOUTHEAST COLORADO AND FAR WESTERN KANSAS. THE PRESSURE
GRADIENT WILL TIGHTEN TODAY WITH LAKE MICHIGAN BETWEEN THESE TWO
SYSTEMS. SOUTHEAST WINDS WILL INCREASE AS A RESULT THEN TURN SOUTH
AND SOUTHWEST TUESDAY. SOUTH TO SOUTHWEST WINDS WILL THEN CONTINUE
THROUGH THE REST OF THE WEEK AS THE HIGH REMAINS TO THE EAST AND
SEVERAL LOW PRESSURE SYSTEMS MOVE NORTHWEST OF THE LAKE. WIND SPEEDS
WILL GENERALLY BE IN THE 15 TO 25 KT RANGE WITH PERIODIC INCREASES
TO THE HIGHER END OF THAT RANGE...WITH 30 KT POSSIBLE AT TIMES...BUT
THERE WILL ALSO BE PERIODS IN THE 10 TO 20 OR 15-20 KT RANGE. WARMER
AIR MOVING IN WILL HELP LIMIT THE GUSTS...ESPECIALLY OVER THE OPEN
WATERS BUT SOME OF THE TALLER PILOT HOUSES AND SHORE BASED OB SITES
COULD SEE GUSTS JUST ABOVE 30 KT AT TIMES AS THEY WOULD BE ABOVE THE
STABLE MARINE LAYER. NEARSHORE AREAS WILL FLIRT WITH SMALL CRAFT
ADVISORY CRITERIA AT TIMES AS WELL BUT AT THIS POINT WILL KEEP WINDS
AT 15 TO 25 KT WITH PERIODS OF 20-25 KT LOOKING BRIEF AND DIFFICULT
TO PIN DOWN.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS LINCOLN IL
1233 PM CDT MON MAY 27 2013
.DISCUSSION...
ISSUED 1030 AM CDT MON MAY 27 2013
WELL DEFINED MCV ON RADAR CENTERED JUST EAST OF BLOOMINGTON...
WITH LINGERING SHOWERS DIMINISHING AHEAD OF IT. MCS TO OUR WEST
CONTINUES TO DROP SOUTHEAST...WITH A COUPLE OF WAKE LOWS NORTH OF
IT ACROSS IOWA. THE CORE OF THE LINE OF STORMS IS PROJECTED TO
REMAIN IN MISSOURI. HAVE SEEN AN OVERALL EASTWARD PUSH OF THE RAIN
WHICH WAS NEAR QUINCY AT 1030 AM...AND THE HRRR MODEL...WHICH HAS
HANDLED THIS MCS PRETTY WELL...BRINGS THE REMNANTS THROUGH THE
SOUTHWEST HALF OF THE CWA EARLY AFTERNOON AND REACHING THE EASTERN
CWA LATE. HAVE SEEN TEMPS ACROSS THE SOUTHEAST SURGING TOWARD 80
DEGREES WITH SOME SUNSHINE FILTERING THROUGH...AND WILL NEED TO
MONITOR THE INSTABILITY HERE AS THE STORMS ARRIVE FOR ANY
ENHANCEMENT.
GEELHART
&&
.AVIATION...
ISSUED 1233 PM CDT MON MAY 27 2013
LINE OF THUNDERSTORMS PUSHING EAST FROM THE MISSISSIPPI RIVER AT
MIDDAY...SHOULD REACH KSPI TOWARD 1930Z AND KCMI TOWARD 22Z. HAVE
MENTIONED SOME TEMPO IFR CONDITIONS AS THE WORST OF THE LINE
PASSES. MORE GENERAL IFR CONDITIONS LIKELY FURTHER NORTH TOWARD
KPIA/KBMI ON THE NORTH SIDE OF THE CONVECTIVE CLUSTER. AS HAS BEEN
THE CASE THE LAST COUPLE DAYS...EVENING CONVECTIVE REDEVELOPMENT
IS A SIGNIFICANT CONCERN...AND FAVORED MORE ALONG/NORTH OF
KPIA/KBMI WHERE THE WARM FRONT BECOMES BETTER ESTABLISHED. HAVE
MENTIONED PREVAILING MVFR CONDITIONS WITH -TSRA IN THOSE AREAS AND
ONLY VCTS FURTHER SOUTH WHERE IT IS MORE QUESTIONABLE. TUESDAY
MORNING...SHOULD SEE GUSTY WINDS DEVELOP AS HIGHER WINDS ALOFT MIX
TOWARD THE SURFACE...WITH SOME POTENTIAL FOR THUNDER AGAIN BY LATE
MORNING.
GEELHART
&&
.PREV DISCUSSION...
ISSUED 340 AM CDT MON MAY 27 2013
SHORT TERM...TODAY THROUGH TUESDAY
WARM FRONT AT 08Z EXTENDED FROM THE IA/MO BORDER SOUTHEAST TO NEAR
MOUNT VERNON. FRONT HAS BECOME MORE DIFFICULT TO DEFINE DUE TO
SEVERAL RECENT CONVECTIVE COMPLEXES AND RESULTING OUTFLOW. THESE
COMPLEXES HAVE BEEN FED BY STRONG 850-700 MB WARM/MOIST
ADVECTION...AND LATEST VWP/S OVER MO INDICATE 30-40 KT FLOW AT
THESE LEVELS SUPPLYING INSTABILITY INTO THE LOW AND MID LEVEL
BOUNDARIES. THIS ACTIVITY SHOULD FESTER INTO THE MORNING BEFORE
THE LLJ VEERS AND WEAKENS BY 15Z. NEXT LARGER UPSTREAM MCS OVER
WESTERN IA IS FORECAST TO DIMINISH BY HI-RES MODELS BY TIME IT
REACHES THE MS RIVER LATER THIS MORNING...BUT THIS COULD SEND
ANOTHER OUTFLOW BOUNDARY INTO THE CWA THIS AFTERNOON. IF CLEARING
OCCURS AFTER THIS MORNINGS STORMS...STRONG TO SEVERE T-STORMS WILL
BE POSSIBLE THIS AFTERNOON DUE TO SHEAR NEARBY SYNOPTIC AND
MESOSCALE BOUNDARIES AND ENHANCED INSTABILITY. SPC HAS EXPANDED
DAY 1 SLIGHT RISK TO INCLUDE THE WESTERN CWA. PRECIPITABLE WATER
REMAINS HIGH AT 1.5-1.7 INCHES SO PERIODS OF HEAVY RAIN POSSIBLE
ONCE AGAIN...AND WITH SATURATED GROUND FROM RECENT RAINS 1-HR FFG
NUMBERS ARE UNDER 1.5 INCHES FOR MUCH OF THE WESTERN HALF OF THE
CWA. WILL EXTEND CURRENT FLASH FLOOD WATCH THROUGH 12Z TUE AND
EXPAND TO INCLUDE ALL COUNTIES ALONG AND WEST OF A MCLEAN TO
SHELBY LINE.
THE WARM FRONT WILL GRADUALLY LIFT NORTH OF THE CWA ON TUESDAY BUT
THIS PROCESS MAY BE IMPEDED BY CONVECTIVE OUTFLOW. RECENT MODEL
RUNS NOW SHOW MORE STORMS WILL BE POSSIBLE TUESDAY...AND HAVE
HIGHEST CHANCES IN THE NORTHERN CWA CLOSER TO THE BOUNDARY.
FORECAST SOUNDINGS LOOK MORE IMPRESSIVE FOR SEVERE STORMS AS THE
BOUNDARY LAYER WILL BE MORE UNSTABLE THAN TODAY AND DEEP LAYER
SHEAR INCREASES.
LONG TERM...WEDNESDAY THROUGH SUNDAY
BY WEDNESDAY WE WILL BE FIRMLY IN THE WARM SECTOR WITH THE FRONT
LIFTING WELL NORTH. BRISK SOUTHERLY WINDS WILL PRODUCE WIDESPREAD
MID 80S HIGHS.
AFTER A BRIEF BREAK FROM THE ACTIVE PATTERN...AN UPPER LOW MOVING
INTO THE PLAINS WILL BRING INCREASING STORM CHANCES FROM THE WEST
FOR THURSDAY AND FRIDAY. 00Z MODEL RUNS ARE MORE PROGRESSIVE WITH
THIS SYSTEM THAN 24 HOURS AGO...AND HIGHER CHANCE POPS FOR THE
WESTERN HALF OF THE CWA FROM THE MODEL CONSENSUS FOR THU/FRI LOOK
GOOD. THE FAR EAST AND SOUTHEAST CWA MAY STAY DRY UNTIL LATER
FRIDAY AND INTO SATURDAY WHEN THE COLD FRONT IS FORECAST TO SHIFT
INTO THE STATE. THE SYNOPTIC SETUP FAVORS MORE HEAVY RAIN AND
POSSIBLE SEVERE WEATHER WITH THIS SYSTEM. TEMPS SHOULD COOL BACK
TO NORMAL IN THE POST-FRONTAL AIRMASS ON SUNDAY.
25
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR ILZ027>031-036>038-
040>043-047>053-061.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1131 AM CDT MON MAY 27 2013
.DISCUSSION...
1055 AM CDT
EARLY CHANGES MADE TO GOING FORECAST FOR THE REST OF TODAY INCLUDE
CUTTING DOWN POPS FOR MUCH OF THE NORTHERN FORECAST AREA THROUGH
AT LEAST EARLY AFTERNOON. ALSO ADJUSTED TEMPERATURES DOWN THE MOST
OVER THIS AREA AS THE COOL MEMORIAL DAY WEEKEND CONTINUES RIGHT
THROUGH THE HOLIDAY.
THE BROAD WARM AIR ADVECTION PATTERN CONTINUES OVER THE AREA
NORTH OF THE SURFACE STATIONARY BOUNDARY WHICH IS DRAPED ACROSS
FAR SOUTHERN IA INTO THE MID-SECTION OF IL. A REMNANT MCV AS SEEN
ON VISIBLE SATELLITE AND RADAR IMAGERY IS MOVING NORTHEAST INTO
NORTHWEST IN LATE THIS MORNING AND IS STARVED OF INSTABILITY...SO
JUST SOME SCATTERED ARCS OF SHOWERS HAVE BEEN SEEN WITH THIS.
SUPPRESSION WEST OF THIS HAS BEEN KEEPING MUCH OF THE NORTHERN HALF
OF THE CWA MAINLY DRY THIS MORNING AND LIMITING THE EASTWARD
PROGRESSION OF THE NEXT AREA OF SHOWERS AND CONVECTION FROM IA.
OBSERVATIONAL TRENDS SUPPORT HIGH RES GUIDANCE SOLUTIONS THAT TAKE
THE MCS IN NORTHEAST MO EASTWARD ACROSS CENTRAL/SOUTH CENTRAL IL
WHICH SHOULD KEEP THE SURFACE FRONT TO THE SOUTH. SO ALL IN ALL
THERE MAY BE LITTLE IN THE WAY OF PRECIP THROUGH MID-AFTERNOON
BESIDES SOME WIDELY SCATTERED SHOWERS OR SPRINKLES. BY LATE
AFTERNOON...THE INFLUENCE OF THE SHORT WAVE IN IA AND MORE FOCUSED
WARM AIR ADVECTION IS FORECAST TO MOVE OVER THE AREA. HOWEVER
LIMITED MOISTURE TRANSPORT RETURN PRIOR TO SUNSET MAY STILL KEEP
MUCH OF THE SHOWER COVERAGE SCATTERED AND MAINLY THUNDER-FREE.
THE EAST WIND NORTH OF THE BOUNDARY ALONG WITH LOW
CIGS...PRIMARILY ALONG AND NORTH OF THE I-88 CORRIDOR...WILL KEEP
TEMPERATURES FROM RECOVERING MUCH. HAVE LOWERED MAX TEMPS QUITE A
BIT TOWARD THE RAP SOLUTION. SOME LOCATIONS ARE LIKELY ONLY TO
CLIMB A COUPLE DEGREES MORE...ESPECIALLY IN LAKE COUNTY IL.
MTF
//PREV DISCUSSION...
318 AM CDT
THE UNSETTLED WEATHER WILL CONTINUE FOR THE NEXT SEVERAL
DAYS...WHICH WILL BE MARKED BY PERIODS OF SHOWERS AND THUNDERSTORMS
AS WELL AS THE RETURN OF MORE SUMMER-LIKE TEMPERATURES.
FOR THE REMAINDER OF THE NIGHT AND INTO THE EARLY MORNING
HOURS...THE FOCUS WILL REMAIN ON THE ONGOING SHOWERS AND
THUNDERSTORMS OVER THE SOUTHERN PORTIONS OF THE CWA. AS OF 3AM
CDT...MUCH OF THE PCPN HAS MOVED OUT OF LIVINGSTON AND FORD COUNTIES
AND IS DIMINISHING OVER IROQUOIS COUNTY. BENTON/JASPER/NEWTON
COUNTIES SHOULD SEE MODERATE TO OCNLY HEAVY PCPN WITH EMBEDDED
THUNDER FOR A FEW MORE HOURS...BUT SHOULD BE WINDING DOWN BY
DAYBREAK. THIS LINE OF HEAVY RAIN IS ALONG THE ELEVATED WARM
FRONT...WITH THE SFC WARM FRONT STILL WELL TO THE SOUTH...FROM NRN
MO TO SRN IL/IN. LATEST RADAR ESTIMATES INDICATE THAT SWATH OF 2-4
INCHES HAS FALLEN GENERALLY ALONG A LINE FROM...PONTIAC TO WATSEKA.
THESE PCPN SHOULD EXTEND EAST TOWARD REMINGTON BEFORE ALL IS SAID
AND DONE. RADAR ESTIMATES AS HIGH AS 5 INCHES ARE INDICATED
IN NORTHWESTERN LIVINGSTON COUNTY...NEAR CORNELL AND LONG POINT.
UNFORTUNATELY...THERE IS STILL A FAIR AMOUNT OF UNCERTAINTY IN THE
MEMORIAL DAY FORECAST AS THE AREA MAY YET BE IMPACTED BY BOUNDARIES
SET OUT BY THE STRONG CONVECTIVE CLUSTERS OVER THE MISSOURI VALLEY.
THE GENERAL TREND FOR THE DAY WILL START OUT WITH SOME SCT SHOWERS
OVER THE NORTHERN PORTIONS OF THE CWA...TOWARD THE WISCONSIN BORDER
AND SOME LINGERING RAIN TO THE SOUTH. THERE WILL LIKELY BE AT LEAST
SOME PERIODS OF DRY WEATHER OVER THE AREA...BUT WITH THE FREQUENTLY
DISCUSSED WARM FRONT SLOWLY MAKING ITS WAY NORTHWARD AND A SERIES OF
SHORT WAVES RIPPLING THROUGH THE DEAMPLIFYING MIDLEVEL FLOW OVER THE
AREA...PERIODS OF SHOWERS AND THUNDERSTORMS ARE LIKELY THROUGH THE
DAY AND INTO TONIGHT. WHILE THE CHANCES FOR SEVERE WEATHER ARE
LOW...ANY THUNDERSTORMS THAT DO FORM CAN MAKE OUTDOOR ACTIVITIES
HAZARDOUS. ALSO...THE ENVIRONMENT HAS BEEN PRIMED WITH INCREASING
AMOUNTS OF DEEP LAYER MOISTURE...SO LOCALLY HEAVY RAINFALL WILL BE
POSSIBLE AS WELL. THE ONE POSITIVE NOTE THAT CAN BE MENTIONED FOR
TODAY IS THE TEMPERATURE TREND. WHILE SKIES WILL LIKELY BE CLOUDY
FOR MUCH OF THE DAY...GRADUALLY BUILDING HEIGHTS ALOFT WILL ALLOW
FOR TEMPERATURES A LITTLE HIGHER THAN RECENT DAYS...WITH HIGHS
RANGING FROM AROUND 60F ALONG THE NORTHERN ILLINOIS SHORE OF LAKE
MICHIGAN...TO THE MIDDLE 70S OVER THE SOUTHWESTERN PORTIONS OF THE
CWA...INCLUDING THE PONTIAC METRO AREA.
THE WARM FRONT IS EXPECTED TO LIFT NWD THROUGH NRN IL/IN OVERNIGHT
TONIGHT AND THEN CONTINUE NWD INTO WISCONSIN ON TUESDAY. THIS WILL
INITIATE THE EXPECTED WARMING TREND IN EARNEST...WITH SOUTHWESTERLY
FLOW SETTING UP IN THE LOWER LEVELS...DRAWING WARMER/MOISTER AIR
INTO THE REGION...AS UPPER RIDGING BEGINS TO BUILD FROM THE SERN
CONUS THROUGH THE UPPER MISSISSIPPI VALLEY. THIS COMBINATION WILL
BRING TEMPERATURES WELL INTO THE 80S...BUT WILL ALSO BRING DEWPOINTS
IN THE MIDDLE TO UPPER 60S. THE TEMPERATURE AND DEWPOINT TREND WILL
BE ON THE INCREASE THROUGH WEDNESDAY AND THURSDAY AS WELL...WITH
DEWPOINTS APPROACHING 70F OVER MUCH OF THE AREA AND TEMPERATURES
REACHING INTO THE MIDDLE 80S...WITH SOME AREAS POSSIBLY REACHING THE
UPPER 80S. THE STRONG SOUTHWESTERLY FLOW WILL OVERCOME ANY LAKE
INFLUENCE AND THE WARMER CONDITIONS WILL BE ABLE TO PENETRATE UP TO
THE LAKE FRONT. WITH UPPER TROUGHING DEVELOPING OVER THE WRN
CONUS...SWLY FLOW WILL SET UP ALOFT AS WELL...WITH THE MODELS
ADVERTISING A SERIES OF IMPULSES RIDING NEWD UP THE BACKSIDE OF THE
RIDGE. WHILE THE MODELS ARE...TYPICALLY...INDICATING TIMING AND
STRENGTH DIFFERENCES TO THE INDIVIDUAL IMPULSES...THE SIGNAL IS
CLEAR THAT THESE WILL BRING ADDITIONAL PERIODS OF SHOWERS AND
THUNDERSTORMS. WITH DEEP LAYER MOISTURE STILL ON THE
INCREASE...WITH PWATS EXPECTED TO BE 1.5-2.0 INCHES THROUGH THE
PERIOD...LOCALLY HEAVY RAINFALL WILL BE A POSSIBILITY.
THE WARM...HUMID...UNSETTLED WEATHER WILL CONTINUE THROUGH FRIDAY.
BY SATURDAY...THE DEEPENING UPPER TROUGH WILL CLOSE OFF INTO A
LARGE...SPRAWLING UPPER LOW AND EVENTUALLY PUSH A COLD FRONT THROUGH
THE REGION. THE LATEST RUNS OF THE GFS/ECMWF ARE INDICATING THAT
THIS NEXT COLD FRONT SHOULD PUSH THROUGH THE AREA ON SATURDAY.
SINCE THIS IS A MODIFIED PACIFIC SYSTEM RATHER THAN A POLAR SYSTEM
DROPPING OUT OF CANADA...TEMPERATURES ARE ONLY EXPECTED TO DROP BACK
INTO THE 70S FOR NEXT WEEKEND.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* IFR CIGS PERSIST...PSBLY SOME IMPROVEMENT EARLY THIS AFTN TO
LOW END MVFR.
* EAST/SOUTHEAST WINDS 10-14KT WITH OCCASIONAL GUSTS IN THE
16-20KT RANGE.
* PATCHY DZ WILL END...BEST CHC FOR SHRA/TSRA AFD 00Z THRU OVERNIGHT
HOURS.
BEACHLER
//DISCUSSION...UPDATED 12Z...
TOUGH FORECAST CONTINUES WITH CIG TRENDS AND SHRA/TSRA
CHANCES/TIMING THE MAIN CHALLENGES. IFR CIGS DEVELOPED A FEW HOURS
AGO IN THE WAKE OF A BAND OF SHRA/TSRA THAT PASSED MAINLY TO THE
SOUTH OF THE TERMINALS. WEAK LOW PRESSURE IS JUST NORTH OF STL
WITH A WARM FRONTAL BOUNDARY STRETCHING TO ITS EAST. THIS FRONT
LOOKS TO REMAIN SOUTH OF THE AREA INTO THIS EVENING THANKS TO THE
PASSAGE OF SHRA/TSRA SOUTH OF THE TERMINALS OVERNIGHT. THIS
COMPLICATES THE FORECAST BECAUSE WITH THE FRONT TO THE SOUTH IFR
CIGS MAY BE HELD IN PLACE FOR AN EXTENDED PERIOD OF TIME. RIGHT
NOW EXPECT IFR THROUGH MID TO LATE MORNING BUT AM THINKING THERE
WILL BE SOME IMPROVEMENT THIS AFTERNOON AS WARMING OCCURS AND
CURRENT POCKETS OF LIGHT RAIN EXIT THE AREA. CONFIDENCE IN HOW
QUICKLY IMPROVEMENT OCCURS IS LOW BUT DO NOT SEE IMPROVEMENT ANY
EARLIER THAN IN THE TAF. PROVIDED IMPROVEMENT DOES OCCUR...IT
WOULD LIKELY ONLY BE TO LOW END MVFR WITH SLOW IMPROVEMENT FROM
THERE.
LIGHT RAIN WILL CONTINUE TO EXIT TO THE EAST OVER THE NEXT FEW
HOURS. BEYOND THAT...A BAND OF RAIN DOWN NEAR PIA WILL LIKELY PASS
SOUTH OF THE TERMINALS THIS MORNING. A LARGE COMPLEX OF WEAKENING
SHRA/TSRA IS MOVING EAST ACROSS CENTRAL IOWA WITH A WELL DEFINED
CIRCULATION BEYOND IT. THIS CIRCULATION WILL LIKELY CONTINUE EAST
AND REACH THE AREA EARLY THIS AFTERNOON. THIS COULD SERVE SEVERAL
FUNCTIONS...IT MAY MAINTAIN SOME PRECIP ACTIVITY AND BRING IT
ACROSS THE AREA OR IT COULD BE A FOCUS FOR NEW DEVELOPMENT. GIVEN
THAT THE WARM FRONT IS WELL SOUTH AND INSTABILITY IS ALSO A WAYS
AWAY...AND THERE IS ABUNDANT CLOUD COVER NEW DEVELOPMENT SEEMS
UNLIKELY. BASED ON RADAR TRENDS AND OTHER PARAMETERS THERE MAY BE
VERY LITTLE LEFT OF THE CURRENT PRECIP SHIELD. PERHAPS THE MOST
LIKELY EFFECT WILL BE TO DISTURB THE SURFACE WINDS AS IT COMES
ACROSS. THERE IS STILL SOME CHANCE THAT THERE COULD BE SHRA/TSRA
LATER THIS AFTERNOON AND THIS EVENING SO WILL MAINTAIN A PROB30
FOR NOW BUT THERE MAY BE LITTLE ACTIVITY IN THE TERMINAL AREA.
SOME NEW GUIDANCE DELAYS ANY ORGANIZED ACTIVITY UNTIL TUESDAY
MORNING WHICH GIVEN THE FRONTAL BOUNDARY LIKELY REMAINING SOUTH
TODAY MAKES REASONABLE SENSE...THOUGH GUIDANCE HAS BEEN HANDLING
PRECIP TRENDS RATHER POORLY IN THIS PATTERN.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH CONFIDENCE IN IFR CIGS PERSISTING...LOW CONFIDENCE IN
TIMING OF LOW END MVFR CIGS DEVELOPING.
* HIGH CONFIDENCE IN WIND FORECAST.
* LOW CONFIDENCE IN OVERALL SHRA/TSRA TIMING...MEDIUM CONFIDENCE
THAT THE BETTER CHANCES WOULD NOT BE UNTIL LATER TODAY AND
BEYOND.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT THROUGH SATURDAY...MAINLY VFR...PERIODIC SHRA/TSRA
ESPECIALLY TUESDAY NIGHT AND FRIDAY. BREEZY SOUTH WINDS WEDNESDAY
THROUGH SATURDAY.
MDB
&&
.MARINE...
314 AM CDT
HIGH PRESSURE IS MOVING OFF TO THE EAST AND IS NOW POSITIONED FROM
HUDSON BAY DOWN ACROSS LAKE ERIE AND TO THE MID ATLANTIC COAST. LOW
PRESSURE CONTINUES TO DEVELOP ACROSS THE HIGH PLAINS WITH ONE LOW
CENTER OVER SOUTHEAST COLORADO AND FAR WESTERN KANSAS. THE PRESSURE
GRADIENT WILL TIGHTEN TODAY WITH LAKE MICHIGAN BETWEEN THESE TWO
SYSTEMS. SOUTHEAST WINDS WILL INCREASE AS A RESULT THEN TURN SOUTH
AND SOUTHWEST TUESDAY. SOUTH TO SOUTHWEST WINDS WILL THEN CONTINUE
THROUGH THE REST OF THE WEEK AS THE HIGH REMAINS TO THE EAST AND
SEVERAL LOW PRESSURE SYSTEMS MOVE NORTHWEST OF THE LAKE. WIND SPEEDS
WILL GENERALLY BE IN THE 15 TO 25 KT RANGE WITH PERIODIC INCREASES
TO THE HIGHER END OF THAT RANGE...WITH 30 KT POSSIBLE AT TIMES...BUT
THERE WILL ALSO BE PERIODS IN THE 10 TO 20 OR 15-20 KT RANGE. WARMER
AIR MOVING IN WILL HELP LIMIT THE GUSTS...ESPECIALLY OVER THE OPEN
WATERS BUT SOME OF THE TALLER PILOT HOUSES AND SHORE BASED OB SITES
COULD SEE GUSTS JUST ABOVE 30 KT AT TIMES AS THEY WOULD BE ABOVE THE
STABLE MARINE LAYER. NEARSHORE AREAS WILL FLIRT WITH SMALL CRAFT
ADVISORY CRITERIA AT TIMES AS WELL BUT AT THIS POINT WILL KEEP WINDS
AT 15 TO 25 KT WITH PERIODS OF 20-25 KT LOOKING BRIEF AND DIFFICULT
TO PIN DOWN.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
1101 AM CDT MON MAY 27 2013
.DISCUSSION...
1055 AM CDT
EARLY CHANGES MADE TO GOING FORECAST FOR THE REST OF TODAY INCLUDE
CUTTING DOWN POPS FOR MUCH OF THE NORTHERN FORECAST AREA THROUGH
AT LEAST EARLY AFTERNOON. ALSO ADJUSTED TEMPERATURES DOWN THE MOST
OVER THIS AREA AS THE COOL MEMORIAL DAY WEEKEND CONTINUES RIGHT
THROUGH THE HOLIDAY.
THE BROAD WARM AIR ADVECTION PATTERN CONTINUES OVER THE AREA
NORTH OF THE SURFACE STATIONARY BOUNDARY WHICH IS DRAPED ACROSS
FAR SOUTHERN IA INTO THE MID-SECTION OF IL. A REMNANT MCV AS SEEN
ON VISIBLE SATELLITE AND RADAR IMAGERY IS MOVING NORTHEAST INTO
NORTHWEST IN LATE THIS MORNING AND IS STARVED OF INSTABILITY...SO
JUST SOME SCATTERED ARCS OF SHOWERS HAVE BEEN SEEN WITH THIS.
SUPPRESSION WEST OF THIS HAS BEEN KEEPING MUCH OF THE NORTHERN HALF
OF THE CWA MAINLY DRY THIS MORNING AND LIMITING THE EASTWARD
PROGRESSION OF THE NEXT AREA OF SHOWERS AND CONVECTION FROM IA.
OBSERVATIONAL TRENDS SUPPORT HIGH RES GUIDANCE SOLUTIONS THAT TAKE
THE MCS IN NORTHEAST MO EASTWARD ACROSS CENTRAL/SOUTH CENTRAL IL
WHICH SHOULD KEEP THE SURFACE FRONT TO THE SOUTH. SO ALL IN ALL
THERE MAY BE LITTLE IN THE WAY OF PRECIP THROUGH MID-AFTERNOON
BESIDES SOME WIDELY SCATTERED SHOWERS OR SPRINKLES. BY LATE
AFTERNOON...THE INFLUENCE OF THE SHORT WAVE IN IA AND MORE FOCUSED
WARM AIR ADVECTION IS FORECAST TO MOVE OVER THE AREA. HOWEVER
LIMITED MOISTURE TRANSPORT RETURN PRIOR TO SUNSET MAY STILL KEEP
MUCH OF THE SHOWER COVERAGE SCATTERED AND MAINLY THUNDER-FREE.
THE EAST WIND NORTH OF THE BOUNDARY ALONG WITH LOW
CIGS...PRIMARILY ALONG AND NORTH OF THE I-88 CORRIDOR...WILL KEEP
TEMPERATURES FROM RECOVERING MUCH. HAVE LOWERED MAX TEMPS QUITE A
BIT TOWARD THE RAP SOLUTION. SOME LOCATIONS ARE LIKELY ONLY TO
CLIMB A COUPLE DEGREES MORE...ESPECIALLY IN LAKE COUNTY IL.
MTF
&&
.PREV DISCUSSION...
318 AM CDT
THE UNSETTLED WEATHER WILL CONTINUE FOR THE NEXT SEVERAL
DAYS...WHICH WILL BE MARKED BY PERIODS OF SHOWERS AND THUNDERSTORMS
AS WELL AS THE RETURN OF MORE SUMMER-LIKE TEMPERATURES.
FOR THE REMAINDER OF THE NIGHT AND INTO THE EARLY MORNING
HOURS...THE FOCUS WILL REMAIN ON THE ONGOING SHOWERS AND
THUNDERSTORMS OVER THE SOUTHERN PORTIONS OF THE CWA. AS OF 3AM
CDT...MUCH OF THE PCPN HAS MOVED OUT OF LIVINGSTON AND FORD COUNTIES
AND IS DIMINISHING OVER IROQUOIS COUNTY. BENTON/JASPER/NEWTON
COUNTIES SHOULD SEE MODERATE TO OCNLY HEAVY PCPN WITH EMBEDDED
THUNDER FOR A FEW MORE HOURS...BUT SHOULD BE WINDING DOWN BY
DAYBREAK. THIS LINE OF HEAVY RAIN IS ALONG THE ELEVATED WARM
FRONT...WITH THE SFC WARM FRONT STILL WELL TO THE SOUTH...FROM NRN
MO TO SRN IL/IN. LATEST RADAR ESTIMATES INDICATE THAT SWATH OF 2-4
INCHES HAS FALLEN GENERALLY ALONG A LINE FROM...PONTIAC TO WATSEKA.
THESE PCPN SHOULD EXTEND EAST TOWARD REMINGTON BEFORE ALL IS SAID
AND DONE. RADAR ESTIMATES AS HIGH AS 5 INCHES ARE INDICATED
IN NORTHWESTERN LIVINGSTON COUNTY...NEAR CORNELL AND LONG POINT.
UNFORTUNATELY...THERE IS STILL A FAIR AMOUNT OF UNCERTAINTY IN THE
MEMORIAL DAY FORECAST AS THE AREA MAY YET BE IMPACTED BY BOUNDARIES
SET OUT BY THE STRONG CONVECTIVE CLUSTERS OVER THE MISSOURI VALLEY.
THE GENERAL TREND FOR THE DAY WILL START OUT WITH SOME SCT SHOWERS
OVER THE NORTHERN PORTIONS OF THE CWA...TOWARD THE WISCONSIN BORDER
AND SOME LINGERING RAIN TO THE SOUTH. THERE WILL LIKELY BE AT LEAST
SOME PERIODS OF DRY WEATHER OVER THE AREA...BUT WITH THE FREQUENTLY
DISCUSSED WARM FRONT SLOWLY MAKING ITS WAY NORTHWARD AND A SERIES OF
SHORT WAVES RIPPLING THROUGH THE DEAMPLIFYING MIDLEVEL FLOW OVER THE
AREA...PERIODS OF SHOWERS AND THUNDERSTORMS ARE LIKELY THROUGH THE
DAY AND INTO TONIGHT. WHILE THE CHANCES FOR SEVERE WEATHER ARE
LOW...ANY THUNDERSTORMS THAT DO FORM CAN MAKE OUTDOOR ACTIVITIES
HAZARDOUS. ALSO...THE ENVIRONMENT HAS BEEN PRIMED WITH INCREASING
AMOUNTS OF DEEP LAYER MOISTURE...SO LOCALLY HEAVY RAINFALL WILL BE
POSSIBLE AS WELL. THE ONE POSITIVE NOTE THAT CAN BE MENTIONED FOR
TODAY IS THE TEMPERATURE TREND. WHILE SKIES WILL LIKELY BE CLOUDY
FOR MUCH OF THE DAY...GRADUALLY BUILDING HEIGHTS ALOFT WILL ALLOW
FOR TEMPERATURES A LITTLE HIGHER THAN RECENT DAYS...WITH HIGHS
RANGING FROM AROUND 60F ALONG THE NORTHERN ILLINOIS SHORE OF LAKE
MICHIGAN...TO THE MIDDLE 70S OVER THE SOUTHWESTERN PORTIONS OF THE
CWA...INCLUDING THE PONTIAC METRO AREA.
THE WARM FRONT IS EXPECTED TO LIFT NWD THROUGH NRN IL/IN OVERNIGHT
TONIGHT AND THEN CONTINUE NWD INTO WISCONSIN ON TUESDAY. THIS WILL
INITIATE THE EXPECTED WARMING TREND IN EARNEST...WITH SOUTHWESTERLY
FLOW SETTING UP IN THE LOWER LEVELS...DRAWING WARMER/MOISTER AIR
INTO THE REGION...AS UPPER RIDGING BEGINS TO BUILD FROM THE SERN
CONUS THROUGH THE UPPER MISSISSIPPI VALLEY. THIS COMBINATION WILL
BRING TEMPERATURES WELL INTO THE 80S...BUT WILL ALSO BRING DEWPOINTS
IN THE MIDDLE TO UPPER 60S. THE TEMPERATURE AND DEWPOINT TREND WILL
BE ON THE INCREASE THROUGH WEDNESDAY AND THURSDAY AS WELL...WITH
DEWPOINTS APPROACHING 70F OVER MUCH OF THE AREA AND TEMPERATURES
REACHING INTO THE MIDDLE 80S...WITH SOME AREAS POSSIBLY REACHING THE
UPPER 80S. THE STRONG SOUTHWESTERLY FLOW WILL OVERCOME ANY LAKE
INFLUENCE AND THE WARMER CONDITIONS WILL BE ABLE TO PENETRATE UP TO
THE LAKE FRONT. WITH UPPER TROUGHING DEVELOPING OVER THE WRN
CONUS...SWLY FLOW WILL SET UP ALOFT AS WELL...WITH THE MODELS
ADVERTISING A SERIES OF IMPULSES RIDING NEWD UP THE BACKSIDE OF THE
RIDGE. WHILE THE MODELS ARE...TYPICALLY...INDICATING TIMING AND
STRENGTH DIFFERENCES TO THE INDIVIDUAL IMPULSES...THE SIGNAL IS
CLEAR THAT THESE WILL BRING ADDITIONAL PERIODS OF SHOWERS AND
THUNDERSTORMS. WITH DEEP LAYER MOISTURE STILL ON THE
INCREASE...WITH PWATS EXPECTED TO BE 1.5-2.0 INCHES THROUGH THE
PERIOD...LOCALLY HEAVY RAINFALL WILL BE A POSSIBILITY.
THE WARM...HUMID...UNSETTLED WEATHER WILL CONTINUE THROUGH FRIDAY.
BY SATURDAY...THE DEEPENING UPPER TROUGH WILL CLOSE OFF INTO A
LARGE...SPRAWLING UPPER LOW AND EVENTUALLY PUSH A COLD FRONT THROUGH
THE REGION. THE LATEST RUNS OF THE GFS/ECMWF ARE INDICATING THAT
THIS NEXT COLD FRONT SHOULD PUSH THROUGH THE AREA ON SATURDAY.
SINCE THIS IS A MODIFIED PACIFIC SYSTEM RATHER THAN A POLAR SYSTEM
DROPPING OUT OF CANADA...TEMPERATURES ARE ONLY EXPECTED TO DROP BACK
INTO THE 70S FOR NEXT WEEKEND.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* IFR CIGS PERSIST...PSBLY SOME IMPROVEMENT LATER THIS MORNING
THRU EARLY THIS AFTN TO LOW END MVFR.
* EAST/SOUTHEAST WINDS 10-14KT WITH OCCASIONAL GUSTS IN THE
16-20KT RANGE.
* PATCHY DZ WILL END...BEST CHC FOR SHRA/TSRA ARND 00Z THRU
OVERNIGHT HOURS.
BEACHLER
//DISCUSSION...UPDATED 12Z...
TOUGH FORECAST CONTINUES WITH CIG TRENDS AND SHRA/TSRA
CHANCES/TIMING THE MAIN CHALLENGES. IFR CIGS DEVELOPED A FEW HOURS
AGO IN THE WAKE OF A BAND OF SHRA/TSRA THAT PASSED MAINLY TO THE
SOUTH OF THE TERMINALS. WEAK LOW PRESSURE IS JUST NORTH OF STL
WITH A WARM FRONTAL BOUNDARY STRETCHING TO ITS EAST. THIS FRONT
LOOKS TO REMAIN SOUTH OF THE AREA INTO THIS EVENING THANKS TO THE
PASSAGE OF SHRA/TSRA SOUTH OF THE TERMINALS OVERNIGHT. THIS
COMPLICATES THE FORECAST BECAUSE WITH THE FRONT TO THE SOUTH IFR
CIGS MAY BE HELD IN PLACE FOR AN EXTENDED PERIOD OF TIME. RIGHT
NOW EXPECT IFR THROUGH MID TO LATE MORNING BUT AM THINKING THERE
WILL BE SOME IMPROVEMENT THIS AFTERNOON AS WARMING OCCURS AND
CURRENT POCKETS OF LIGHT RAIN EXIT THE AREA. CONFIDENCE IN HOW
QUICKLY IMPROVEMENT OCCURS IS LOW BUT DO NOT SEE IMPROVEMENT ANY
EARLIER THAN IN THE TAF. PROVIDED IMPROVEMENT DOES OCCUR...IT
WOULD LIKELY ONLY BE TO LOW END MVFR WITH SLOW IMPROVEMENT FROM
THERE.
LIGHT RAIN WILL CONTINUE TO EXIT TO THE EAST OVER THE NEXT FEW
HOURS. BEYOND THAT...A BAND OF RAIN DOWN NEAR PIA WILL LIKELY PASS
SOUTH OF THE TERMINALS THIS MORNING. A LARGE COMPLEX OF WEAKENING
SHRA/TSRA IS MOVING EAST ACROSS CENTRAL IOWA WITH A WELL DEFINED
CIRCULATION BEYOND IT. THIS CIRCULATION WILL LIKELY CONTINUE EAST
AND REACH THE AREA EARLY THIS AFTERNOON. THIS COULD SERVE SEVERAL
FUNCTIONS...IT MAY MAINTAIN SOME PRECIP ACTIVITY AND BRING IT
ACROSS THE AREA OR IT COULD BE A FOCUS FOR NEW DEVELOPMENT. GIVEN
THAT THE WARM FRONT IS WELL SOUTH AND INSTABILITY IS ALSO A WAYS
AWAY...AND THERE IS ABUNDANT CLOUD COVER NEW DEVELOPMENT SEEMS
UNLIKELY. BASED ON RADAR TRENDS AND OTHER PARAMETERS THERE MAY BE
VERY LITTLE LEFT OF THE CURRENT PRECIP SHIELD. PERHAPS THE MOST
LIKELY EFFECT WILL BE TO DISTURB THE SURFACE WINDS AS IT COMES
ACROSS. THERE IS STILL SOME CHANCE THAT THERE COULD BE SHRA/TSRA
LATER THIS AFTERNOON AND THIS EVENING SO WILL MAINTAIN A PROB30
FOR NOW BUT THERE MAY BE LITTLE ACTIVITY IN THE TERMINAL AREA.
SOME NEW GUIDANCE DELAYS ANY ORGANIZED ACTIVITY UNTIL TUESDAY
MORNING WHICH GIVEN THE FRONTAL BOUNDARY LIKELY REMAINING SOUTH
TODAY MAKES REASONABLE SENSE...THOUGH GUIDANCE HAS BEEN HANDLING
PRECIP TRENDS RATHER POORLY IN THIS PATTERN.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* HIGH CONFIDENCE IN IFR CIGS PERSISTING...MEDIUM CONFIDENCE IN
TIMING OF LOW END MVFR CIGS DEVELOPING.
* HIGH CONFIDENCE IN WIND FORECAST.
* LOW CONFIDENCE IN OVERALL SHRA/TSRA TIMING...MEDIUM CONFIDENCE
THAT THE BETTER CHANCES WOULD NOT BE UNTIL LATER TODAY AND
BEYOND.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT THROUGH SATURDAY...MAINLY VFR...PERIODIC SHRA/TSRA
ESPECIALLY TUESDAY NIGHT AND FRIDAY. BREEZY SOUTH WINDS WEDNESDAY
THROUGH SATURDAY.
MDB
&&
.MARINE...
314 AM CDT
HIGH PRESSURE IS MOVING OFF TO THE EAST AND IS NOW POSITIONED FROM
HUDSON BAY DOWN ACROSS LAKE ERIE AND TO THE MID ATLANTIC COAST. LOW
PRESSURE CONTINUES TO DEVELOP ACROSS THE HIGH PLAINS WITH ONE LOW
CENTER OVER SOUTHEAST COLORADO AND FAR WESTERN KANSAS. THE PRESSURE
GRADIENT WILL TIGHTEN TODAY WITH LAKE MICHIGAN BETWEEN THESE TWO
SYSTEMS. SOUTHEAST WINDS WILL INCREASE AS A RESULT THEN TURN SOUTH
AND SOUTHWEST TUESDAY. SOUTH TO SOUTHWEST WINDS WILL THEN CONTINUE
THROUGH THE REST OF THE WEEK AS THE HIGH REMAINS TO THE EAST AND
SEVERAL LOW PRESSURE SYSTEMS MOVE NORTHWEST OF THE LAKE. WIND SPEEDS
WILL GENERALLY BE IN THE 15 TO 25 KT RANGE WITH PERIODIC INCREASES
TO THE HIGHER END OF THAT RANGE...WITH 30 KT POSSIBLE AT TIMES...BUT
THERE WILL ALSO BE PERIODS IN THE 10 TO 20 OR 15-20 KT RANGE. WARMER
AIR MOVING IN WILL HELP LIMIT THE GUSTS...ESPECIALLY OVER THE OPEN
WATERS BUT SOME OF THE TALLER PILOT HOUSES AND SHORE BASED OB SITES
COULD SEE GUSTS JUST ABOVE 30 KT AT TIMES AS THEY WOULD BE ABOVE THE
STABLE MARINE LAYER. NEARSHORE AREAS WILL FLIRT WITH SMALL CRAFT
ADVISORY CRITERIA AT TIMES AS WELL BUT AT THIS POINT WILL KEEP WINDS
AT 15 TO 25 KT WITH PERIODS OF 20-25 KT LOOKING BRIEF AND DIFFICULT
TO PIN DOWN.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS LINCOLN IL
1032 AM CDT MON MAY 27 2013
.DISCUSSION...
ISSUED 1030 AM CDT MON MAY 27 2013
WELL DEFINED MCV ON RADAR CENTERED JUST EAST OF BLOOMINGTON...
WITH LINGERING SHOWERS DIMINISHING AHEAD OF IT. MCS TO OUR WEST
CONTINUES TO DROP SOUTHEAST...WITH A COUPLE OF WAKE LOWS NORTH OF
IT ACROSS IOWA. THE CORE OF THE LINE OF STORMS IS PROJECTED TO
REMAIN IN MISSOURI. HAVE SEEN AN OVERALL EASTWARD PUSH OF THE RAIN
WHICH WAS NEAR QUINCY AT 1030 AM...AND THE HRRR MODEL...WHICH HAS
HANDLED THIS MCS PRETTY WELL...BRINGS THE REMNANTS THROUGH THE
SOUTHWEST HALF OF THE CWA EARLY AFTERNOON AND REACHING THE EASTERN
CWA LATE. HAVE SEEN TEMPS ACROSS THE SOUTHEAST SURGING TOWARD 80
DEGREES WITH SOME SUNSHINE FILTERING THROUGH...AND WILL NEED TO
MONITOR THE INSTABILITY HERE AS THE STORMS ARRIVE FOR ANY
ENHANCEMENT.
GEELHART
&&
.AVIATION...
ISSUED 700 AM CDT MON MAY 27 2013
MULTIPLE CONVECTIVE COMPLEXES WITH HEAVY RAINFALL AFFECTED
CENTRAL IL LAST NIGHT. THE LAST ONE WAS JUST MOVING ACROSS PIA/BMI
AT 12Z. THAT SYSTEM MAY CLIP SPI/DEC/CMI WITH A FEW SHOWERS...BUT
THUNDER SHOULD REMAIN NORTH OF THE SOUTHERN TERMINALS EARLY THIS
MORNING. SATELLITE AND RADAR IMAGES CONFIRM THE NEXT COMPLEX WILL
ARRIVE IN OUR AREA FROM THE WEST TOWARD MID-DAY TODAY...WITH
ANOTHER ROUND OF SHOWERS AND STORMS. SOME OF THE STORMS MAY
CONTAIN STRONG WINDS AND HAIL...MAINLY FARTHER WEST FOR PIA AND
SPI.
SOME MVFR FOG HAS BEEN LINGERING BEHIND THE MOST RECENT LINE OF
SHOWERS AND STORMS...SO WE INDICATED AT LEAST A FEW HOURS OF MVFR
AT PIA AND BMI. IFR CONDITIONS ARE LIKELY DURING THE STRONGER
STORMS...DUE TO A COMBINATION OF LOW VIS AND CIGS.
A WARM FRONT LIFTING NORTH TODAY SHOULD MOVE NORTH OF ALL TAF
SITES BY AFTERNOON...HELPING TO SHIFT WINDS TO THE SOUTHEAST
ACROSS THE BOARD. PREVAILING WIND SPEEDS WILL CLIMB INTO THE
12-15KT RANGE WITH GUSTS AROUND 20 KT AT TIMES.
SHIMON
&&
.PREV DISCUSSION...
ISSUED 340 AM CDT MON MAY 27 2013
SHORT TERM...TODAY THROUGH TUESDAY
WARM FRONT AT 08Z EXTENDED FROM THE IA/MO BORDER SOUTHEAST TO NEAR
MOUNT VERNON. FRONT HAS BECOME MORE DIFFICULT TO DEFINE DUE TO
SEVERAL RECENT CONVECTIVE COMPLEXES AND RESULTING OUTFLOW. THESE
COMPLEXES HAVE BEEN FED BY STRONG 850-700 MB WARM/MOIST
ADVECTION...AND LATEST VWP/S OVER MO INDICATE 30-40 KT FLOW AT
THESE LEVELS SUPPLYING INSTABILITY INTO THE LOW AND MID LEVEL
BOUNDARIES. THIS ACTIVITY SHOULD FESTER INTO THE MORNING BEFORE
THE LLJ VEERS AND WEAKENS BY 15Z. NEXT LARGER UPSTREAM MCS OVER
WESTERN IA IS FORECAST TO DIMINISH BY HI-RES MODELS BY TIME IT
REACHES THE MS RIVER LATER THIS MORNING...BUT THIS COULD SEND
ANOTHER OUTFLOW BOUNDARY INTO THE CWA THIS AFTERNOON. IF CLEARING
OCCURS AFTER THIS MORNINGS STORMS...STRONG TO SEVERE T-STORMS WILL
BE POSSIBLE THIS AFTERNOON DUE TO SHEAR NEARBY SYNOPTIC AND
MESOSCALE BOUNDARIES AND ENHANCED INSTABILITY. SPC HAS EXPANDED
DAY 1 SLIGHT RISK TO INCLUDE THE WESTERN CWA. PRECIPITABLE WATER
REMAINS HIGH AT 1.5-1.7 INCHES SO PERIODS OF HEAVY RAIN POSSIBLE
ONCE AGAIN...AND WITH SATURATED GROUND FROM RECENT RAINS 1-HR FFG
NUMBERS ARE UNDER 1.5 INCHES FOR MUCH OF THE WESTERN HALF OF THE
CWA. WILL EXTEND CURRENT FLASH FLOOD WATCH THROUGH 12Z TUE AND
EXPAND TO INCLUDE ALL COUNTIES ALONG AND WEST OF A MCLEAN TO
SHELBY LINE.
THE WARM FRONT WILL GRADUALLY LIFT NORTH OF THE CWA ON TUESDAY BUT
THIS PROCESS MAY BE IMPEDED BY CONVECTIVE OUTFLOW. RECENT MODEL
RUNS NOW SHOW MORE STORMS WILL BE POSSIBLE TUESDAY...AND HAVE
HIGHEST CHANCES IN THE NORTHERN CWA CLOSER TO THE BOUNDARY.
FORECAST SOUNDINGS LOOK MORE IMPRESSIVE FOR SEVERE STORMS AS THE
BOUNDARY LAYER WILL BE MORE UNSTABLE THAN TODAY AND DEEP LAYER
SHEAR INCREASES.
LONG TERM...WEDNESDAY THROUGH SUNDAY
BY WEDNESDAY WE WILL BE FIRMLY IN THE WARM SECTOR WITH THE FRONT
LIFTING WELL NORTH. BRISK SOUTHERLY WINDS WILL PRODUCE WIDESPREAD
MID 80S HIGHS.
AFTER A BRIEF BREAK FROM THE ACTIVE PATTERN...AN UPPER LOW MOVING
INTO THE PLAINS WILL BRING INCREASING STORM CHANCES FROM THE WEST
FOR THURSDAY AND FRIDAY. 00Z MODEL RUNS ARE MORE PROGRESSIVE WITH
THIS SYSTEM THAN 24 HOURS AGO...AND HIGHER CHANCE POPS FOR THE
WESTERN HALF OF THE CWA FROM THE MODEL CONSENSUS FOR THU/FRI LOOK
GOOD. THE FAR EAST AND SOUTHEAST CWA MAY STAY DRY UNTIL LATER
FRIDAY AND INTO SATURDAY WHEN THE COLD FRONT IS FORECAST TO SHIFT
INTO THE STATE. THE SYNOPTIC SETUP FAVORS MORE HEAVY RAIN AND
POSSIBLE SEVERE WEATHER WITH THIS SYSTEM. TEMPS SHOULD COOL BACK
TO NORMAL IN THE POST-FRONTAL AIRMASS ON SUNDAY.
25
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR ILZ027>031-036>038-
040>043-047>053-061.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1235 AM EDT MON MAY 27 2013
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 244 PM EDT SUN MAY 26 2013
CENTRAL INDIANA WILL REMAIN NORTH OF A WARM FRONT INTO MONDAY...THEN
THE FRONT WILL PUSH THROUGH THE AREA. THE THREAT FOR RAIN WILL
REMAIN ACROSS AREAS NEAR AND NORTH OF IT. BY TUESDAY NIGHT THE FRONT
WILL BE FAR ENOUGH NORTH FOR DRY WEATHER TO RETURN.
DRY AND WARM WEATHER WILL THEN RULE THROUGH FRIDAY. CHANCES FOR RAIN
&&
.NEAR TERM /OVERNIGHT/...
ISSUED AT 1001 PM EDT SUN MAY 26 2013
ISOLATED SHOWERS THROUGHOUT THE FORECAST AREA THIS EVENING WITH A
LARGER AREA OF RAIN SLOWLY SPREADING INTO THE NORTHERN WABASH
VALLEY. TEMPS WERE GENERALLY IN THE 60S AT 02Z.
SERIES OF UPPER LEVEL SHORTWAVES EXTENDING FROM IOWA AND MINNESOTA
SOUTHEAST INTO ILLINOIS. CURRENT RAP SHOWING DEVELOPING LOW
LEVEL JET TO THE WEST OF THE REGION...LIKELY INFLUENCING ONGOING
DEVELOPMENT ACROSS SOUTHERN IOWA AND NORTHERN MISSOURI. THE LOW
LEVEL JET WILL BRING ADDITIONAL MOISTURE INTO CENTRAL INDIANA AND
COMBINED WITH ENHANCED FORCING ALOFT AS THE SHORTWAVES DRIFT
ACROSS THE REGION OVERNIGHT...ANTICIPATE UPSTREAM CONVECTION
LIKELY TO EXPAND SOUTHEAST INTO THE FORECAST AREA AS THE NIGHT
PROGRESSES. WILL CONTINUE TO CARRY ISOLATED THUNDER LATE TONIGHT
WITH WEAK ELEVATED INSTABILITY PRESENT. WILL CARRY HIGHEST POPS
NORTH OF I-70. BUMPED LOWS UP A DEGREE OR TWO BASED AS CURRENT
TEMPS RUNNING A FEW DEGREES WARMER THAN PREVIOUSLY THOUGHT.
ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM /MEMORIAL DAY THROUGH WEDNESDAY/...
ISSUED AT 244 PM EDT SUN MAY 26 2013
FOCUS IS ON CHANCES FOR RAIN THROUGH THE PERIOD. MODELS ARE CLOSE
ENOUGH THAT A BLEND CAN BE USED FOR MOST FEATURES.
THE WARM FRONT WILL LIFT NORTH ACROSS THE AREA ON MONDAY. THERE
REMAINS SOME UNCERTAINTY IN HOW PRECIPITATION WILL EVOLVE FROM THE
LEFTOVER CONVECTION FROM THE NIGHT INTO THE AFTERNOON CONVECTION.
MODELS HAVE BEEN STRUGGLING LATELY WITH PRECIPITATION COVERAGE AND
TIMING.
FOR NOW HAVE CHOSEN TO GO HIGHEST POPS WITH THE MORNING CONVECTION
/WITH SOME UPPER SUPPORT/...THEN GRADUALLY LOWERING THROUGH THE
AFTERNOON FROM SOUTH TO NORTH AS THE FRONT PUSHES NORTH. CONFIDENCE
IS NOT HIGH THOUGH. GENERALLY STUCK WITH A BLEND OF MOS FOR
TEMPERATURES.
WENT CHANCE POPS MONDAY NIGHT EARLY...THEN DECREASED THEM THROUGH
THE NIGHT FROM SOUTH TO NORTH. AGAIN WENT GENERALLY WITH A BLEND FOR
TEMPERATURES.
KEPT LOW POPS ACROSS THE FAR NORTH ON TUESDAY WITH THE WARM FRONT
STILL IN THE VICINITY THERE. WENT DRY ELSEWHERE. WITH THE WARM FRONT
THROUGH ON TUESDAY...WENT CLOSER TO THE WARMER OF THE MOS NUMBERS
FOR HIGHS.
DRY AND WARM CONDITIONS CAN THEN BE EXPECTED WITH AN UPPER RIDGE
BUILDING INTO THE AREA.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
ISSUED AT 202 PM EDT SUN MAY 26 2013
MODELS IN GOOD AGREEMENT ON PERSISTENT FLOW OFF GULF AIR ACROSS
CENTRAL INDIANA THROUGH AT LEAST SATURDAY. HOWEVER...THE 12Z GFS AND
00Z GEFS ARE MUCH FASTER MOVING A PLAINS FRONT THROUGH CENTRAL
INDIANA SATURDAY NIGHT AS OPPOSED TO THE 00Z ECMWF...THAT DOES NOT
PUSH THE FRONT THROUGH UNTIL BEYOND SUNDAY. WITH UNCERTAINTY...WPC
OFFERS A REASONABLE BLEND BRINGING THE FRONT ACROSS ON SUNDAY. AT
ANY RATE...RETURN FLOW SHOULD ALLOW FOR ABOVE NORMAL TEMPERATURES IN
THE 80S THROUGH SATURDAY AND SLIGHTLY COOLER NORTHWEST BEHIND THE
FRONT ON SUNDAY.
WILL KEEP IT MOSTLY DRY THROUGH FRIDAY NIGHT AND THEN THUNDERSTORM
CHANCES BY SATURDAY AS THE FRONT GETS CLOSER.
&&
.AVIATION /DISCUSSION FOR THE 270600Z TAFS/...
ISSUED AT 1235 AM EDT MON MAY 27 2013
SCATTERED RAIN SHOWERS WILL CONTINUE TO DRIFT ACROSS TAF SITES FOR
DURATION OF TAF PERIOD AS WARM FRONT REMAINS JUST TO THE SOUTH OF
CENTRAL INDIANA. A FEW LIGHTNING STRIKES COULD OCCUR THROUGH
DAYBREAK...BUT IT STILL REMAINS TOO ISOLATED TO INCLUDE IN TAFS FOR
THAT TIME FRAME. CONVECTION CURRENTLY OVER ILLINOIS CONTAINS MUCH
MORE PERSISTENT LIGHTNING. SO...CHANCES WILL BE BETTER BY LATE
MORNING/EARLY AFTERNOON ACROSS TAF SITES AS ENVIRONMENT DESTABILIZES
AND THAT SHOWER/THUNDERSTORM ACTIVITY PUSHES INTO THE AREA. KEPT
VCTS FOR NOW IN TAFS STARTING LATE THIS MORNING/EARLY THIS AFTERNOON
UNTIL IT CAN BE BETTER PINPOINTED WITH FUTURE TAF ISSUANCES. WINDS
WILL TAKE ON MORE OF A SOUTHERLY COMPONENT THROUGH THE COURSE OF THE
TAF PERIOD...AND WILL BE SUSTAINED AT 6 TO 12 KTS. VFR CONDITIONS
WILL BE THE PREVAILING FLIGHT CATEGORY WITH PERIODS OF MVFR DUE TO
REDUCED VISIBILITIES IN ANY SHOWERS/THUNDERSTORMS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...RYAN
SHORT TERM...50
LONG TERM....MK
AVIATION...TDUD
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AREA FORECAST DISCUSSION
NWS TOPEKA KS
356 PM CDT MON MAY 27 2013
.MESOSCALE DISCUSSION...
ISSUED AT 353 PM CDT MON MAY 27 2013
LATEST THOUGHTS WITH RESPECT TO CONVECTIVE DEVELOPMENT FOR THE REST
OF THE DAY. SHORT RANGE MODELS SUCH AS HRRR SHOW SUPERCELLULAR
DEVELOPMENT SPREADING OVER NC KANSAS OVER THE NEXT COUPLE HOURS.
THAT SCENARIO SEEMS UNLIKELY AT THIS POINT...AS THE MOISTURE
GRADIENT ALONG THE DRYLINE HAS BEEN ANALYZED IN THE KHYS TO KGBD
AREA. ALSO CURRENT VIS IMAGERY STILL SHOWS LITTLE IN THE WAY OF
CONVECTIVE TOWERS NEAR THE LOW LEVEL CONVERGENCE ZONE...LIKELY DUE
TO THE STRONG CAP IN PLACE. IT IS STARTING TO LOOK AS IF THE ONLY
WAY THE CAP WILL BREAK IS BY THE MID LEVEL WAVE CURRENTLY OVER THE
CO/KS BORDER (CURRENTLY KICKING OFF SOME CONVECTION IN THE HIGH
PLAINS). STILL NOT RULING OUT SUPERCELLULAR DEVELOPMENT WITH ALL OF
THE ADVERTISED HAZARDS...BUT IT COULD POSSIBLY START A LITTLE
FURTHER WEST AND A LITTLE LATER THAN ANTICIPATED...WHICH WOULD DELAY
ANY STORMS FROM REACHING REPUBLIC...CLOUD...AND OTTAWA COUNTIES
UNTIL A LITTLE LATER...PERHAPS 00Z TO 02Z. WILL CONTINUE TO MONITOR
THE TRENDS AND UPDATE ACCORDINGLY.
JL
&&
.SHORT TERM...
ISSUED AT 243 PM CDT MON MAY 27 2013
REST OF MONDAY THROUGH TONIGHT...
SURFACE ANALYSIS AT 18Z SHOWS A STRONG SURFACE CYCLONE AROUND 998 TO
1000 MB LOCATED JUST WEST OF KHYS. THE SURFACE TROUGH IS GETTING A
BIT DEEPER AS THE DAY PROGRESSES AS EARLIER IT WAS ANALYZED BETWEEN
1000 TO 1002 MB. THE TIGHT SURFACE PRESSURE GRADIENT HAS ALLOWED FOR
SOUTHERLY WINDS TO PUSH NORTHWARD USHERING IN GOOD RICH GULF
MOISTURE INTO EASTERN KANSAS. VISIBLE IMAGERY SHOWS A VERY WELL
DEFINED OUTFLOW BOUNDARY FROM THIS MORNING`S MCS LIES ON A LINE FROM
KIMP ARCING SOUTHEASTWARD TOWARD KPPF. SKIES HAVE BEEN CLEAR ACROSS
THE AREA LEADING TO SIGNIFICANT DESTABILIZATION...CHARACTERIZED BY
ML CAPE VALUES OF AROUND 3000 TO 4000 J/KG. AS MORE MOISTURE STREAMS
INTO THE AREA AND HEATING CONTINUES WE COULD SEE BOUNDARY LAYER
CONDITIONS IN THE LOWER 80S WITH DEWPOINTS IN THE UPPER 60S TO LOWER
70S. THIS WOULD LIKELY LEAD TO ML CAPE VALUES HIGHER THAN THE
CURRENT 3000 J/KG. ALSO AT THE SURFACE A VERY PRONOUNCED DRY LINE IS
CURRENTLY ANALYZED NOSING INTO THE KGBD AREA. HOT/DRY SOUTHWEST
WINDS ARE CURRENTLY ENCOUNTERING THE MOIST E/SE WINDS IN THAT KGBD
AREA. THIS AREA WILL PROVIDE THE BEST LOW LEVEL CONVERGENCE FOR
ASCENT...ONCE WE CAN ERODE THE CAP AND GET SOME MID LEVEL ASCENT.
CURRENTLY THE VISIBLE SATELLITE NEAR THE DRYLINE/OUTFLOW
BOUNDARY/WARM FRONT TRIPLE POINT AREA SHOWS LITTLE IN THE WAY OF
CUMULUS FIELD DEVELOPMENT AS THE CAP HOLDS STRONG. FURTHER WEST ON
SATELLITE IT LOOKS AS THOUGH HIGH BASED DEEP CONVECTION IS
OCCURRING...PROBABLY IN RESPONSE TO AN APPROACHING SHORTWAVE TROUGH
COMING OFF THE HIGH PLAINS. ONCE THAT MID LEVEL ASCENT REACHES
CENTRAL KANSAS EXPECT RAPID DEVELOPMENT OF STRONG THUNDERSTORMS
CAPABLE OF PRODUCING LARGE HAIL...STRONG WINDS...AND POSSIBLY SOME
TORNADOES.
EXPECT CONVECTIVE INITIATION TO OCCUR BETWEEN 21 AND 22Z WITH
INITIAL DEVELOPMENT TAKING PLACE BETWEEN KGBD AND K9K7 (ELLSWORTH).
DEEP LAYER SHEAR VECTORS COME OUT OF THE WEST AT 40 TO 50 KTS
INDICATING THAT STORMS WILL BE ABLE TO GROW UPSCALE TO SUPERCELLS
VERY QUICKLY WHILE MOVING EASTWARD. GIVEN THE STRONG SHEAR/CAPE
RELATIONSHIP IT APPEARS LIKELY THAT LARGE HAIL UP TO THE SIZE OF
BASEBALLS WILL OCCUR WITH ANY STORM THAT CAN REMAIN DISCRETE. SINCE
STORMS WILL BE SURFACE BASED IT IS ALSO LIKELY THAT THE STRONGEST
STORMS WILL BE ABLE TO PRODUCE STRONG WINDS POTENTIALLY REACHING 70
TO 80 MPH.
THE TORNADO THREAT FOR PORTIONS OF CENTRAL AND NORTH CENTRAL KANSAS
REMAIN RATHER ELEVATED FOR TONIGHT. THE MOST STRIKING PART OF THIS
PARTICULAR EVENT...OTHER THAN THE EXTREME CAPE/AND DEEP LAYER SHEAR
IS THE STRONGLY CLOCKWISE CURVED HODOGRAPHS. THE OUTFLOW
BOUNDARY...IN COMBO WITH THE SURFACE SYNOPTIC WINDS HAVE CAUSED A
STRONG SOUTHEASTERLY COMPONENT TO THE SURFACE WINDS. IN THE 21Z TO
03Z TIME FRAME MODELS INDICATED A BACKING AND STRENGTHENING OF THE
LOW LEVEL JET TO AROUND 25 KTS BY 00Z AND UP TO 40-50 KTS BY 03Z.
THIS WILL CAUSE A LENGTHENING OF THE LOW LEVEL HODOGRAPH...YIELDING
0-1 SRH VALUES APPROACHING 150 J/KG BY 00Z AND OVER 300 J/KG BY 03Z.
SHOULD A SUPERCELL OR TWO BE ABLE TO STAY DISCREET IN GOOD MOISTURE
WITH LOW LCL`S THE EXTREME LOW LEVEL SHEAR WILL MAKE TORNADIC
ACTIVITY A STRONG POSSIBILITY...ESPECIALLY ACROSS C/NC KANSAS...WEST
OF MANHATTAN.
IT IS TOUGH TO SAY EXACTLY HOW LONG THE STORMS WILL BE ABLE TO
REMAIN DISCREET...AS SOME SHORT RANGE MODELS INDICATE A QUICK
TRANSITION INTO LINEAR MODE...PERHAPS AS EARLY AS 01Z. SHOULD STORMS
REMAIN DISCREET THE TORNADO THREAT WILL CONTINUE THROUGH THE
NIGHT...HOWEVER AS STORMS BECOME MORE CONGEALED AND LINEAR IN NATURE
THE TORNADO THREAT WILL DIMINISH SOMEWHAT...BUT AS THE LOW LEVEL
SHEAR INCREASES OVERNIGHT EVEN LINEAR CONVECTION WILL BE ABLE TO
PRODUCE TORNADIC SPIN UPS...ESPECIALLY IF IT ENCOUNTERS ANY
LINGERING BOUNDARIES FROM PREVIOUS CONVECTION...ESPECIALLY THE PRE
EXISTING OUT FLOW BOUNDARY. THE LINEAR MCS WILL ALSO HAVE A STRONG
WIND THREAT AS IT MOVES EASTWARD THROUGH THE EASTERN HALF OF THE
FORECAST AREA LATER TONIGHT. SOME MODEL GUIDANCE INDICATES THAT THE
LINEAR CONVECTION MAY EXIT THE AREA BY MIDNIGHT...OR PERHAPS A
COUPLE HOURS THEREAFTER. EXPECT MOSTLY LIGHT LINGERING RAIN THROUGH
TUESDAY MORNING AFTER THE HEAVIEST RAIN FROM THE MCS MOVES EAST OF
THE AREA.
JL
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 243 PM CDT MON MAY 27 2013
SEVERE THUNDERSTORMS MAY RETURN TO THE AREA ON TUESDAY AFTERNOON BUT
MUCH REMAINS TO BE RESOLVED IN TERMS OF SMALL SCALE FEATURES AND
OUTFLOW FROM TONIGHTS CONVECTION. IT SEEMS AS THOUGH THE MORNING WILL
PROBABLY BE DRY WITH ANY MCS ACTIVITY HAVING PUSHED OUT OF THE AREA.
BY AFTERNOON MOST MODEL GUIDANCE SUGGESTS A SOUTHWEST TO NORTHEAST
ORIENTED CONVERGENCE ZONE NEARLY BISECTING THE FORECAST AREA. THIS
SHOULD BECOME A FOCUS FOR AFTERNOON CAP WEAKENING...LIKELY TO THE
POINT OF CONVECTIVE INITIATION WITHIN THE FORECAST AREA BY MID TO
LATE AFTERNOON. THIS WILL ONCE AGAIN BE A STRONGLY UNSTABLE AIRMASS
WITH AROUND 40 KTS OF DEEP LAYER SHEAR. IT MAY BE MORE DIFFICULT TO
MAINTAIN DISCRETE CONVECTION GIVEN THE ORIENTATION OF THE BOUNDARY
BUT WITH SUPERCELL ACTIVITY POSSIBLE AT LEAST INITIALLY...ALL MODES
OF SEVERE WEATHER WOULD SEEM PLAUSIBLE...WITH A FOCUS ACROSS NORTH
CENTRAL KANSAS...AND PERHAPS INTO NORTHEAST KANSAS. MAY SEE ANOTHER
ROUND OF OVERNIGHT MCS ACTIVITY DEPENDING UPON THE EVOLUTION OF THE
EVENING THUNDERSTORMS.
WEDNESDAY MORNING MAY SEE REMNANT MCS ACTIVITY HANGING AROUND THE
FORECAST AREA BEFORE CLEARING FROM WEST TO EAST DURING THE
AFTERNOON. THE PRIMARY TROUGH AXIS WILL BE APPROACHING FROM THE WEST
BY WEDNESDAY AFTERNOON WITH STRONG ASCENT OVERSPREADING WESTERN
KANSAS. WIDESPREAD THUNDERSTORMS WILL DEVELOP AMIDST THE ASCENT TO
THE WEST...AND WHILE THE STORM MOTION WILL HAVE QUITE A BIT OF A
NORTHERLY COMPONENT TO IT...THIS ACTIVITY WILL SPREAD EAST INTO
NORTH CENTRAL KANSAS BY EVENING...AND LIKELY GROW UPSCALE INTO AN
MCS WITH SEVERE POTENTIAL ON WEDNESDAY NIGHT.
THE THURSDAY FORECAST WILL BE GREATLY INFLUENCED BY CONVECTION LEFT
OVER FROM WEDNESDAY NIGHT. THERE ALSO SEEMS TO BE A CHANCE FOR
WIDESPREAD THUNDERSTORMS THROUGH THE MORNING AND PERHAPS EARLY
AFTERNOON AS THE STRONG SHORT WAVE TROUGH AXIS PASSES OVERHEAD.
SHOULD SEE SUBSIDENCE IMMEDIATELY BEHIND THIS WAVE THOUGH WHICH
COULD ALLOW SOME ATMOSPHERIC RECOVERY BY LATE AFTERNOON/EVENING.
CONVECTIVE MODE AND EVOLUTION ARE THE GREATEST QUESTION MARK ON
THURSDAY AS THERE IS SUFFICIENT INSTABILITY AND MORE THAN ENOUGH
WIND SHEAR TO SUPPORT POTENTIAL FOR AT LEAST ONE...IF NOT MULTIPLE
ROUNDS OF STRONG TO SEVERE THUNDERSTORMS. SHEAR PROFILES EXHIBIT
MUCH TURNING WITH HEIGHT...SUGGESTIVE OF ENHANCED LOW LEVEL
MESOCYCLONE POTENTIAL.
THURSDAY NIGHT THE MAIN UPPER LEVEL LOW CONTINUES TO ADVANCE
EASTWARD INTO THE NORTHERN PLAINS WHILE SHORTWAVES ROTATE FURTHER
SOUTH ACROSS OUR AREA. IT SEEMS THAT EACH SHORTWAVE WILL BRING THE
CHANCE OF SEVERE STORMS WITH INSTABILITY AND SHEAR IN
PLACE...ESPECIALLY THURSDAY NIGHT AS THE ECMWF WANTS TO INCREASE
THE INSTABILITY ACROSS KANSAS AND DEVELOP THUNDERSTORMS WHICH WILL
MOVE THROUGH NORTHEAST KANSAS. ON FRIDAY IT APPEARS THE MAIN
ENERGY WILL DRAG A FRONT ACROSS THE AREA BRINGING MORE WIDESPREAD
SHOWERS AND THUNDERSTORMS WHICH MAY BE SEVERE. PRECIP LOOKS TO
CONTINUE INTO SATURDAY AS THE FRONT SLIDES SOUTHEAST. THE SEVERE
THREAT LOOKS TO REMAIN SOUTH OF THE AREA AT THIS POINT WITH BETTER
INSTABILITY ACROSS OKLAHOMA. THE MODELS BEGIN TO DISAGREE ON HOW
THE UPPER LEVEL ENERGY LIFTS NORTHEAST WITH THE GFS KEEPING MORE
ENERGY ACROSS THE SOUTHWEST AND IS SLOWER MOVING THE FRONT AND
PRECIP OUT OF THE AREA. THEREFORE HAVE KEPT THE POPS THROUGH
SUNDAY MORNING FOR OUR SOUTHEAST AREAS. SUNDAY AND BEYOND LOOK TO
BE DRY AS THE MAIN ENERGY WORKS INTO THE GREAT LAKES REGION.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 107 PM CDT MON MAY 27 2013
LOW LEVEL STRATUS SHOULD GRADUALLY DISSIPATE OVER THE NEXT COUPLE
HOURS...AS VISIBLE IMAGERY SHOWS THAT THE CLOUDS ARE VERY THIN IN
NATURE. THIS IS EVIDENT ALSO BY THE SUNLIGHT PRESENT
OUTSIDE...GIVEN THE IFR STRATUS. LATER TONIGHT THERE WILL BE
STRONG THUNDERSTORMS IN C/NC KANSAS THAT WILL MOVE EASTWARD AND
AFFECT THE AVIATION SITES AROUND MIDNIGHT...WITH KMHK BEING
AFFECTED 1-2 HOURS PRIOR TO KTOP/KFOE. EXPECT THE HEAVIEST RAIN TO
EXIT THE AREA BY 8Z WITH A FEW LINGERING SHOWERS THROUGH 8-10Z.
JL
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE...LEIGHTON
SHORT TERM...LEIGHTON
LONG TERM...BARJENBRUCH/SANDERS
AVIATION...LEIGHTON
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1153 AM MDT MON MAY 27 2013
.UPDATE...
ISSUED AT 925 AM MDT MON MAY 27 2013
MAIN CHANGES TO THE CURRENT FORECAST FOR TODAY WERE TO INCREASE
THE WINDS TODAY AND TO ADD A MENTION OF FOG FOR RED WILLOW COUNTY
UNTIL EARLY AFTERNOON.
LATEST OBSERVATIONS PLACE A SURFACE LOW IN THE NESS CITY AREA.
NORTH OF THE SURFACE LOW AN AXIS OF HIGHER DEW POINTS AND MID
LEVEL LIFT HAVE CONTRIBUTED TO A BAND OF LOW STRATUS. FURTHER
NORTH OVER RED WILLOW COUNTY AND VICINITY A COLD FRONT IS
BEGINNING TO MOVE INTO THE TRI-STATE AREA. AS THE COOLER AIR MOVES
IN THE BOUNDARY LAYER HAS BECOME SATURATED CAUSING VISIBILITIES TO
DROP TO HALF A MILE AT TIMES. THE FOG SHOULD LIFT NOT LONG INTO
THE EARLY AFTERNOON AS TEMPERATURES WARM WITH THE AFTERNOON
HEATING. AM THINKING THE COOLER AIR SHOULD NOT MOVE ANY FURTHER
SOUTH THAN HIGHWAY 24 AND NO FURTHER WEST THAN THE CO/KS BORDER
TODAY.
WINDS HAVE BEEN SOMEWHAT TRICKY AS NO GUIDANCE IS REALLY CATCHING
WHAT IS GOING ON. IN GENERAL THE WINDS WILL REMAIN BREEZY DUE TO A
TIGHT PRESSURE GRADIENT OVER THE EASTERN 2/3S OF THE AREA. THE
WINDS MAY BACK OFF SOME DURING THE MID AFTERNOON BEFORE
STRENGTHENING AGAIN AS A SURFACE HIGH PRESSURE MOVES INTO THE AREA
FROM THE WEST CAUSING THE PRESSURE GRADIENT TO TIGHTEN.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 435 AM MDT MON MAY 27 2013
MAIN FORECAST PROBLEM WILL BE CONTINUED CHANCES FOR THUNDERSTORMS.
SATELLITE SHOWING THE FLOW HAS DEAMPLIFIED OVER THE PACIFIC AND THE
PACIFIC NORTHWEST. WHAT USED TO BE A COMPLEX UPPER LOW OVER THE
PACIFIC NORTHWEST HAS NOW BEEN SPLIT APART WITH THE SOUTHERN
PORTION COMING EAST NOW AS AN OPEN SHORTWAVE TROUGH. WITH WEAKENING
MID LEVEL RIDGE TO OUR EAST...THIS LEAVES OUR AREA IN A SOUTHWEST
FLOW ALOFT WITH NUMEROUS SMALL SCALE SHORTWAVE TROUGHS EMBEDDED
WITHIN IT. A COMPLEX SURFACE PATTERN IS OVER THE AREA WITH A
RETREATING WARM FRONT OVER THE NORTHWEST PORTION OF THE AREA WHICH
IS EXTENDING FROM THE SURFACE LOW OVER SOUTHEAST COLORADO. THE DRY
LINE IS JUST TO THE EAST OF THAT. A SHALLOWER/COOLER AIR MASS IS TO
THE NORTH OF THIS WARM FRONT.
MODELS INITIALIZED WELL AT JET LEVEL. MODELS DID FINE AT MID LEVELS
WITH THE GFS...CANADIAN AND UKMET DOING THE BEST ON THE HEIGHTS AND
FEATURES. THE MODELS WERE WARM AT 700 MB WITH THE CANADIAN DOING
THE BEST. MODELS HAVING HARD TIME WITH THE SURFACE PATTERN. MAJORITY
HAVE THE SURFACE LOW THAT STARTS OUT OVER SOUTHEAST COLORADO TOO
FAR EAST BY 06Z. THE ECMWF AND RUC DEFINITELY IS HEAD AND SHOULDERS
ABOVE THE REST. WOULD ALSO HAVE TO GIVE THE ECMWF A SLIGHT EDGE ON
THE THERMAL FIELD AS WELL.
BASED ON RECENT POOR MODEL PERFORMANCE...COMPLEX NATURE OF SURFACE
PATTERN...AND CONVECTIVE FEEDBACK ISSUES WITH THE MODELS...THIS IS
A LOW CONFIDENCE FORECAST. THIS COMPOUNDED BY THE FACT THAT CERTAIN
NEIGHBORING OFFICES ARE MAKING BIG CHANGES WITHOUT TALKING.
TODAY/TONIGHT...SOME CONVECTION HAS DEVELOPED NORTH OF THE
RETREATING WARM FRONT WITH OTHER CONVECTION ON THE WESTWARD
EXTENSION OF THIS WEAVING/COMPLEX FRONTAL POSITION. RECENT TRENDS
AND MESOSCALE MODEL OUTPUT INDICATE ALL THIS PRECIPITATION WILL STAY
TO THE NORTH OF THE AREA. BUT WILL CONTINUE TO MONITOR.
LEFT FRONT QUADRANT OF THE JET STARTS OVER THE SOUTHERN PORTION OF
THE AREA AT 12Z AND IS AFFECTING/OVER THE NORTHERN PORTION OF THE
AREA BY THE END OF THE DAY. THIS FEATURE THEN MOVES SOUTHEAST DURING
THE NIGHT. RIGHT NOW THE MODELS ARE HAVING EXTREME DIFFICULTIES IN
RESOLVING BOUNDARY POSITION AND TIMING. MODELS TAKE A COMPACT 700
MB LOW OVER COLORADO AND MOVE IN TO THE NORTH OF THE AREA BY EARLY
AFTERNOON. DEPENDING ON WHICH MODEL OUTPUT YOU USE...SOME
WRAPAROUND OCCURS WITH THIS. CONSIDERING THE TRAJECTORY...AM NOT
BUYING IT. WITH THE JET...SURFACE BOUNDARY POSITION AND THIS
SYSTEM...BEST CHANCES FOR PRECIPITATION SHOULD BE IN THE NORTH AND
END BY LATE IN THE AFTERNOON. ADDITIONAL SHORTWAVE ENERGY MOVES
THROUGH DURING THE NIGHT BUT MOISTURE HAS BEEN SCOURED OUT. ENDED
PRECIPITATION BY LATE IN THE NIGHT AND THAT MAY BE TOO LATE.
WILL GET SOME FOG AND STRATUS IN THE NORTHWEST PORTION OF THE AREA
AS THE FRONT MOVES THROUGH. WITH AN EARLIER FRONTAL ARRIVAL
EXPECTED...HIGH TEMPERATURES SHOULD BE COOLER BUT AM NOT CERTAIN
ABOUT THAT.
TUESDAY/TUESDAY NIGHT...LEE TROUGH REDEVELOPS/STRENGTHENS AS
STRONGER SHORTWAVE STARTS APPROACHING FROM THE WEST. MAIN SURFACE
CONVERGENCE REMAINS TO THE WEST OF THE AREA THROUGH THE DAY.
SURFACE BOUNDARY DOES NOT MOVE INTO THE AREA UNTIL LATER IN THE
NIGHT. PLUS MAIN LIFT DOES NOT ARRIVE UNTIL DURING THE NIGHT AS
WELL. SO HAVE SLIGHT CHANCE DURING THE AFTERNOON WITH THE MAIN
CHANCE OF PRECIPITATION DURING THE NIGHT. WITH STRENGTHENING
EASTERLY WINDS DURING THE DAY...AM THINKING THAT CURRENT MAX
TEMPERATURES WILL NEED TO BE COOLED SOME WAS NOT ABLE TO SPEND A LOT
OF TIME ON THAT.
WEDNESDAY/WEDNESDAY NIGHT...MODELS MOVE/DEVELOP A LEFT FRONT QUADRANT
OF THE JET OVER THE CENTRAL/EASTERN PORTION OF THE AREA DURING THE
AFTERNOON. THEN MODELS DIFFER ON HOW THEY MOVE IT. SOME MOVE IT EAST
OF THE AREA BY LATE AFTERNOON WITH OTHERS KEEPING IT THERE. THEN
THE SLOWER MODELS MOVE IT EAST OF THE AREA DURING THE EVENING.
MODELS DIFFER ON THE SPEED IN WHICH THEY TAKE THE NEXT BOUNDARY
THROUGH. IF THIS IS SLOWER THEN BETTER PRECIPITATION CHANCES WILL
NEED TO BE PULLED BACK SLOWER. DID SIDE WITH THE SLOWER ARRIVAL BUT
THIS WILL NEED TO BE LOOKED AT. MAIN MID LEVEL LIFT ARRIVES IN THE
AFTERNOON AND EVENING. ALL THIS POINTS TO GOOD CHANCES OF
PRECIPITATION LATER IN THE DAY INTO THE EVENING...ESPECIALLY FOR
THE EASTERN PORTION OF THE AREA. NOT SURE ABOUT WHAT THE
TEMPERATURES WILL DO WITH THE DIFFERENCE IN THE BOUNDARY POSITIONS.
.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 435 AM MDT MON MAY 27 2013
MODELS ARE IN A LITTLE BETTER AGREEMENT WITH MOVEMENT OF UPPER
LOW/TROUGH...MINOR DIFFERENCES IN PLACEMENT OF UPPER LOW/TROUGH
EXIST. THE GFS HAS THE UPPER LOW OVER THE NORTHERN ROCKIES MOVING
EAST AND THE ADJACENT SURFACE LOW OVER THE DAKOTAS ON THURSDAY AND
FRIDAY. THE ECMWF PLACES THE UPPER LOW/TROUGH SLIGHTLY FURTHER NORTH
AND WEST...WHICH IS SLOWER MOVING EAST BUT SHOULD NOT AFFECT THE
TIMING OF THE MAIN FEATURES TOO MUCH. AS THE SURFACE LOW AND UPPER
LOW MOVE EAST...A COLD FRONT WILL SWING THROUGH THE CWA THURSDAY
MORNING. COLD AIR ALOFT WILL FILTER IN BEHIND THE FRONT...THIS
COMBINED WITH VORTICITY WRAPPING AROUND THE UPPER LOW AND SOME MINOR
INSTABILITY WILL BRING A CHANCE FOR SHOWERS AND TSTORMS ON THURSDAY
AFTERNOON. THE UPPER LOW STARTS TO PULL AWAY FROM THE CWA ON FRIDAY
LEAVING SOME LINGERING CLOUDS AND ON SATURDAY CONDITIONS WILL BECOME
CLEAR AS HIGH PRESSURE MOVES INTO THE CWA. MORE SEASONABLE
TEMPERATURES IN THE MID TO UPPER 70S WILL OCCUR ON FRIDAY AND
SATURDAY. SOUTHERLY RETURN FLOW SETS UP ON SUNDAY AFTERNOON OVER THE
CWA AND THE GFS HAS LOW AMPLITUDE RIDGING OVER THE CWA WITH EMBEDDED
SHORTWAVES MOVING THROUGH COLORADO WHILE THE ECMWF HAS ZONAL FLOW
OVER THE CENTRAL PLAINS. POPS WERE LEFT OUT OF SUNDAY FOR NOW...THIS
MAY CHANGE DEPENDING ON HOW MODELS RESOLVE THEIR DIFFERENCES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1143 AM MDT MON MAY 27 2013
VFR TO IFR CONDITIONS ARE FORECAST FOR THE 18Z TAFS. LATEST
VISIBLE SATELLITE IMAGERY INDICATES AN AREA OF IFR TO MVFR
CEILINGS BEHIND THE ADVANCING COLD FRONT...WITH
SHOWERS/THUNDERSTORMS DEVELOPING AHEAD OF THE FRONT. AS
TEMPERATURES WARM WITH AFTERNOON HEATING THE CEILINGS AT KMCK
SHOULD SLOWLY INCREASE...BECOMING SCATTERED BY LATE AFTERNOON.
OVERNIGHT CEILINGS/VIS WILL DROP AS HIGHER DEW POINTS ARE BROUGHT
INTO THE SITE. CONDITIONS WILL IMPROVE BY MID MORNING TUESDAY.
THERE IS A SMALL CHANCE FOR THUNDERSTORMS FOR THE KMCK SITE
THROUGH THE EVENING...HOWEVER THEY WILL BE ISOLATED SO DO NOT HAVE
ENOUGH CONFIDENCE AT THIS TIME TO PLACE A MENTION IN THE TAF.
FOR KGLD CLOUD DECK SHOULD REMAIN SCATTERED AHEAD OF THE COLD
FRONT. AM ANTICIPATING THUNDERSTORMS TO DEVELOP NEAR THE SITE
DURING THE LATE AFTERNOON/EARLY EVENING WHEN INSTABILITY AND LIFT
ARE BEST. DURING THE REST OF THE EVENING THERE MAY BE ISOLATED
STORMS LINGERING...BUT AM NOT VERY CONFIDENT THEY WILL BE NEAR THE
SITE. OVERNIGHT LOW CLOUDS RETURN AS HIGHER DEW POINTS ARE
ADVECTED OVER THE SITE. THE CEILINGS IMPROVE BY MID MORNING
TUESDAY.
&&
.FIRE WEATHER...
ISSUED AT 435 AM MDT MON MAY 27 2013
FOR TODAY...DUE TO THE FRONT MOVING IN FASTER...IT LOOKS LIKE THE
AREA WILL ESCAPE ANY FIRE WEATHER ISSUES. IF FRONT DOES SLOW UP...
GREELEY AND WICHITA COULD REACH CRITERIA.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...BULLER
LONG TERM...ALW
AVIATION...JTL
FIRE WEATHER...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
936 AM MDT MON MAY 27 2013
.UPDATE...
ISSUED AT 925 AM MDT MON MAY 27 2013
MAIN CHANGES TO THE CURRENT FORECAST FOR TODAY WERE TO INCREASE
THE WINDS TODAY AND TO ADD A MENTION OF FOG FOR RED WILLOW COUNTY
UNTIL EARLY AFTERNOON.
LATEST OBSERVATIONS PLACE A SURFACE LOW IN THE NESS CITY AREA.
NORTH OF THE SURFACE LOW AN AXIS OF HIGHER DEW POINTS AND MID
LEVEL LIFT HAVE CONTRIBUTED TO A BAND OF LOW STRATUS. FURTHER
NORTH OVER RED WILLOW COUNTY AND VICINITY A COLD FRONT IS
BEGINNING TO MOVE INTO THE TRI-STATE AREA. AS THE COOLER AIR MOVES
IN THE BOUNDARY LAYER HAS BECOME SATURATED CAUSING VISIBILITIES TO
DROP TO HALF A MILE AT TIMES. THE FOG SHOULD LIFT NOT LONG INTO
THE EARLY AFTERNOON AS TEMPERATURES WARM WITH THE AFTERNOON
HEATING. AM THINKING THE COOLER AIR SHOULD NOT MOVE ANY FURTHER
SOUTH THAN HIGHWAY 24 AND NO FURTHER WEST THAN THE CO/KS BORDER
TODAY.
WINDS HAVE BEEN SOMEWHAT TRICKY AS NO GUIDANCE IS REALLY CATCHING
WHAT IS GOING ON. IN GENERAL THE WINDS WILL REMAIN BREEZY DUE TO A
TIGHT PRESSURE GRADIENT OVER THE EASTERN 2/3S OF THE AREA. THE
WINDS MAY BACK OFF SOME DURING THE MID AFTERNOON BEFORE
STRENGTHENING AGAIN AS A SURFACE HIGH PRESSURE MOVES INTO THE AREA
FROM THE WEST CAUSING THE PRESSURE GRADIENT TO TIGHTEN.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 435 AM MDT MON MAY 27 2013
MAIN FORECAST PROBLEM WILL BE CONTINUED CHANCES FOR THUNDERSTORMS.
SATELLITE SHOWING THE FLOW HAS DEAMPLIFIED OVER THE PACIFIC AND THE
PACIFIC NORTHWEST. WHAT USED TO BE A COMPLEX UPPER LOW OVER THE
PACIFIC NORTHWEST HAS NOW BEEN SPLIT APART WITH THE SOUTHERN
PORTION COMING EAST NOW AS AN OPEN SHORTWAVE TROUGH. WITH WEAKENING
MID LEVEL RIDGE TO OUR EAST...THIS LEAVES OUR AREA IN A SOUTHWEST
FLOW ALOFT WITH NUMEROUS SMALL SCALE SHORTWAVE TROUGHS EMBEDDED
WITHIN IT. A COMPLEX SURFACE PATTERN IS OVER THE AREA WITH A
RETREATING WARM FRONT OVER THE NORTHWEST PORTION OF THE AREA WHICH
IS EXTENDING FROM THE SURFACE LOW OVER SOUTHEAST COLORADO. THE DRY
LINE IS JUST TO THE EAST OF THAT. A SHALLOWER/COOLER AIR MASS IS TO
THE NORTH OF THIS WARM FRONT.
MODELS INITIALIZED WELL AT JET LEVEL. MODELS DID FINE AT MID LEVELS
WITH THE GFS...CANADIAN AND UKMET DOING THE BEST ON THE HEIGHTS AND
FEATURES. THE MODELS WERE WARM AT 700 MB WITH THE CANADIAN DOING
THE BEST. MODELS HAVING HARD TIME WITH THE SURFACE PATTERN. MAJORITY
HAVE THE SURFACE LOW THAT STARTS OUT OVER SOUTHEAST COLORADO TOO
FAR EAST BY 06Z. THE ECMWF AND RUC DEFINITELY IS HEAD AND SHOULDERS
ABOVE THE REST. WOULD ALSO HAVE TO GIVE THE ECMWF A SLIGHT EDGE ON
THE THERMAL FIELD AS WELL.
BASED ON RECENT POOR MODEL PERFORMANCE...COMPLEX NATURE OF SURFACE
PATTERN...AND CONVECTIVE FEEDBACK ISSUES WITH THE MODELS...THIS IS
A LOW CONFIDENCE FORECAST. THIS COMPOUNDED BY THE FACT THAT CERTAIN
NEIGHBORING OFFICES ARE MAKING BIG CHANGES WITHOUT TALKING.
TODAY/TONIGHT...SOME CONVECTION HAS DEVELOPED NORTH OF THE
RETREATING WARM FRONT WITH OTHER CONVECTION ON THE WESTWARD
EXTENSION OF THIS WEAVING/COMPLEX FRONTAL POSITION. RECENT TRENDS
AND MESOSCALE MODEL OUTPUT INDICATE ALL THIS PRECIPITATION WILL STAY
TO THE NORTH OF THE AREA. BUT WILL CONTINUE TO MONITOR.
LEFT FRONT QUADRANT OF THE JET STARTS OVER THE SOUTHERN PORTION OF
THE AREA AT 12Z AND IS AFFECTING/OVER THE NORTHERN PORTION OF THE
AREA BY THE END OF THE DAY. THIS FEATURE THEN MOVES SOUTHEAST DURING
THE NIGHT. RIGHT NOW THE MODELS ARE HAVING EXTREME DIFFICULTIES IN
RESOLVING BOUNDARY POSITION AND TIMING. MODELS TAKE A COMPACT 700
MB LOW OVER COLORADO AND MOVE IN TO THE NORTH OF THE AREA BY EARLY
AFTERNOON. DEPENDING ON WHICH MODEL OUTPUT YOU USE...SOME
WRAPAROUND OCCURS WITH THIS. CONSIDERING THE TRAJECTORY...AM NOT
BUYING IT. WITH THE JET...SURFACE BOUNDARY POSITION AND THIS
SYSTEM...BEST CHANCES FOR PRECIPITATION SHOULD BE IN THE NORTH AND
END BY LATE IN THE AFTERNOON. ADDITIONAL SHORTWAVE ENERGY MOVES
THROUGH DURING THE NIGHT BUT MOISTURE HAS BEEN SCOURED OUT. ENDED
PRECIPITATION BY LATE IN THE NIGHT AND THAT MAY BE TOO LATE.
WILL GET SOME FOG AND STRATUS IN THE NORTHWEST PORTION OF THE AREA
AS THE FRONT MOVES THROUGH. WITH AN EARLIER FRONTAL ARRIVAL
EXPECTED...HIGH TEMPERATURES SHOULD BE COOLER BUT AM NOT CERTAIN
ABOUT THAT.
TUESDAY/TUESDAY NIGHT...LEE TROUGH REDEVELOPS/STRENGTHENS AS
STRONGER SHORTWAVE STARTS APPROACHING FROM THE WEST. MAIN SURFACE
CONVERGENCE REMAINS TO THE WEST OF THE AREA THROUGH THE DAY.
SURFACE BOUNDARY DOES NOT MOVE INTO THE AREA UNTIL LATER IN THE
NIGHT. PLUS MAIN LIFT DOES NOT ARRIVE UNTIL DURING THE NIGHT AS
WELL. SO HAVE SLIGHT CHANCE DURING THE AFTERNOON WITH THE MAIN
CHANCE OF PRECIPITATION DURING THE NIGHT. WITH STRENGTHENING
EASTERLY WINDS DURING THE DAY...AM THINKING THAT CURRENT MAX
TEMPERATURES WILL NEED TO BE COOLED SOME WAS NOT ABLE TO SPEND A LOT
OF TIME ON THAT.
WEDNESDAY/WEDNESDAY NIGHT...MODELS MOVE/DEVELOP A LEFT FRONT QUADRANT
OF THE JET OVER THE CENTRAL/EASTERN PORTION OF THE AREA DURING THE
AFTERNOON. THEN MODELS DIFFER ON HOW THEY MOVE IT. SOME MOVE IT EAST
OF THE AREA BY LATE AFTERNOON WITH OTHERS KEEPING IT THERE. THEN
THE SLOWER MODELS MOVE IT EAST OF THE AREA DURING THE EVENING.
MODELS DIFFER ON THE SPEED IN WHICH THEY TAKE THE NEXT BOUNDARY
THROUGH. IF THIS IS SLOWER THEN BETTER PRECIPITATION CHANCES WILL
NEED TO BE PULLED BACK SLOWER. DID SIDE WITH THE SLOWER ARRIVAL BUT
THIS WILL NEED TO BE LOOKED AT. MAIN MID LEVEL LIFT ARRIVES IN THE
AFTERNOON AND EVENING. ALL THIS POINTS TO GOOD CHANCES OF
PRECIPITATION LATER IN THE DAY INTO THE EVENING...ESPECIALLY FOR
THE EASTERN PORTION OF THE AREA. NOT SURE ABOUT WHAT THE
TEMPERATURES WILL DO WITH THE DIFFERENCE IN THE BOUNDARY POSITIONS.
.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 435 AM MDT MON MAY 27 2013
MODELS ARE IN A LITTLE BETTER AGREEMENT WITH MOVEMENT OF UPPER
LOW/TROUGH...MINOR DIFFERENCES IN PLACEMENT OF UPPER LOW/TROUGH
EXIST. THE GFS HAS THE UPPER LOW OVER THE NORTHERN ROCKIES MOVING
EAST AND THE ADJACENT SURFACE LOW OVER THE DAKOTAS ON THURSDAY AND
FRIDAY. THE ECMWF PLACES THE UPPER LOW/TROUGH SLIGHTLY FURTHER NORTH
AND WEST...WHICH IS SLOWER MOVING EAST BUT SHOULD NOT AFFECT THE
TIMING OF THE MAIN FEATURES TOO MUCH. AS THE SURFACE LOW AND UPPER
LOW MOVE EAST...A COLD FRONT WILL SWING THROUGH THE CWA THURSDAY
MORNING. COLD AIR ALOFT WILL FILTER IN BEHIND THE FRONT...THIS
COMBINED WITH VORTICITY WRAPPING AROUND THE UPPER LOW AND SOME MINOR
INSTABILITY WILL BRING A CHANCE FOR SHOWERS AND TSTORMS ON THURSDAY
AFTERNOON. THE UPPER LOW STARTS TO PULL AWAY FROM THE CWA ON FRIDAY
LEAVING SOME LINGERING CLOUDS AND ON SATURDAY CONDITIONS WILL BECOME
CLEAR AS HIGH PRESSURE MOVES INTO THE CWA. MORE SEASONABLE
TEMPERATURES IN THE MID TO UPPER 70S WILL OCCUR ON FRIDAY AND
SATURDAY. SOUTHERLY RETURN FLOW SETS UP ON SUNDAY AFTERNOON OVER THE
CWA AND THE GFS HAS LOW AMPLITUDE RIDGING OVER THE CWA WITH EMBEDDED
SHORTWAVES MOVING THROUGH COLORADO WHILE THE ECMWF HAS ZONAL FLOW
OVER THE CENTRAL PLAINS. POPS WERE LEFT OUT OF SUNDAY FOR NOW...THIS
MAY CHANGE DEPENDING ON HOW MODELS RESOLVE THEIR DIFFERENCES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 538 AM MDT MON MAY 27 2013
VFR CONDITIONS ARE EXPECTED THROUGH MOST OF THE PERIOD. SHOWERS
AND THUNDERSTORMS ARE POSSIBLE ONCE AGAIN AT BOTH TAF SITES DUE
TO A SURFACE LOW OVER COLORADO MOVING EAST. MVF CONDITIONS COULD
BE POSSIBLE TUESDAY MORNING DUE TO LOW STRATUS...BUT GIVEN THE
TREND OVER THE PAST FEW DAYS...NOT SURE HOW THAT WILL PAN OUT.
&&
.FIRE WEATHER...
ISSUED AT 435 AM MDT MON MAY 27 2013
FOR TODAY...DUE TO THE FRONT MOVING IN FASTER...IT LOOKS LIKE THE
AREA WILL ESCAPE ANY FIRE WEATHER ISSUES. IF FRONT DOES SLOW UP...
GREELEY AND WICHITA COULD REACH CRITERIA.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...BULLER
LONG TERM...ALW
AVIATION...BULLER/ALW
FIRE WEATHER...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
610 AM MDT MON MAY 27 2013
.UPDATE...
ISSUED AT 607 AM MDT MON MAY 27 2013
JUST COMPLETED AN UPDATE. EXTENT OF FOG AND STRATUS HAS NOT
DEVELOPED AS EXPECTED AND LIMITED THEM IN THE UPDATE TO EASTERN
COLORADO. ALSO NEW THUNDERSTORM DEVELOPMENT WEST OF AREA IS HOLD
TOGETHER AND SO STARTED THUNDERSTORMS A LITTLE EARLIER OUT THERE
THAN WHAT WAS IN THERE. MODELS STILL PLAYING CATCH UP ON THE WIND
FIELD. WIND SHIFT IS FURTHER SOUTH THAN ANY MODEL DATA AND WHAT
CURRENT GRIDS HAD. SO USING THE FASTEST MODEL AND REALITY ADJUSTED
THE WIND FIELD FOR THIS MORNING.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 435 AM MDT MON MAY 27 2013
MAIN FORECAST PROBLEM WILL BE CONTINUED CHANCES FOR THUNDERSTORMS.
SATELLITE SHOWING THE FLOW HAS DEAMPLIFIED OVER THE PACIFIC AND THE
PACIFIC NORTHWEST. WHAT USED TO BE A COMPLEX UPPER LOW OVER THE
PACIFIC NORTHWEST HAS NOW BEEN SPLIT APART WITH THE SOUTHERN
PORTION COMING EAST NOW AS AN OPEN SHORTWAVE TROUGH. WITH WEAKENING
MID LEVEL RIDGE TO OUR EAST...THIS LEAVES OUR AREA IN A SOUTHWEST
FLOW ALOFT WITH NUMEROUS SMALL SCALE SHORTWAVE TROUGHS EMBEDDED
WITHIN IT. A COMPLEX SURFACE PATTERN IS OVER THE AREA WITH A
RETREATING WARM FRONT OVER THE NORTHWEST PORTION OF THE AREA WHICH
IS EXTENDING FROM THE SURFACE LOW OVER SOUTHEAST COLORADO. THE DRY
LINE IS JUST TO THE EAST OF THAT. A SHALLOWER/COOLER AIR MASS IS TO
THE NORTH OF THIS WARM FRONT.
MODELS INITIALIZED WELL AT JET LEVEL. MODELS DID FINE AT MID LEVELS
WITH THE GFS...CANADIAN AND UKMET DOING THE BEST ON THE HEIGHTS AND
FEATURES. THE MODELS WERE WARM AT 700 MB WITH THE CANADIAN DOING
THE BEST. MODELS HAVING HARD TIME WITH THE SURFACE PATTERN. MAJORITY
HAVE THE SURFACE LOW THAT STARTS OUT OVER SOUTHEAST COLORADO TOO
FAR EAST BY 06Z. THE ECMWF AND RUC DEFINITELY IS HEAD AND SHOULDERS
ABOVE THE REST. WOULD ALSO HAVE TO GIVE THE ECMWF A SLIGHT EDGE ON
THE THERMAL FIELD AS WELL.
BASED ON RECENT POOR MODEL PERFORMANCE...COMPLEX NATURE OF SURFACE
PATTERN...AND CONVECTIVE FEEDBACK ISSUES WITH THE MODELS...THIS IS
A LOW CONFIDENCE FORECAST. THIS COMPOUNDED BY THE FACT THAT CERTAIN
NEIGHBORING OFFICES ARE MAKING BIG CHANGES WITHOUT TALKING.
TODAY/TONIGHT...SOME CONVECTION HAS DEVELOPED NORTH OF THE
RETREATING WARM FRONT WITH OTHER CONVECTION ON THE WESTWARD
EXTENSION OF THIS WEAVING/COMPLEX FRONTAL POSITION. RECENT TRENDS
AND MESOSCALE MODEL OUTPUT INDICATE ALL THIS PRECIPITATION WILL STAY
TO THE NORTH OF THE AREA. BUT WILL CONTINUE TO MONITOR.
LEFT FRONT QUADRANT OF THE JET STARTS OVER THE SOUTHERN PORTION OF
THE AREA AT 12Z AND IS AFFECTING/OVER THE NORTHERN PORTION OF THE
AREA BY THE END OF THE DAY. THIS FEATURE THEN MOVES SOUTHEAST DURING
THE NIGHT. RIGHT NOW THE MODELS ARE HAVING EXTREME DIFFICULTIES IN
RESOLVING BOUNDARY POSITION AND TIMING. MODELS TAKE A COMPACT 700
MB LOW OVER COLORADO AND MOVE IN TO THE NORTH OF THE AREA BY EARLY
AFTERNOON. DEPENDING ON WHICH MODEL OUTPUT YOU USE...SOME
WRAPAROUND OCCURS WITH THIS. CONSIDERING THE TRAJECTORY...AM NOT
BUYING IT. WITH THE JET...SURFACE BOUNDARY POSITION AND THIS
SYSTEM...BEST CHANCES FOR PRECIPITATION SHOULD BE IN THE NORTH AND
END BY LATE IN THE AFTERNOON. ADDITIONAL SHORTWAVE ENERGY MOVES
THROUGH DURING THE NIGHT BUT MOISTURE HAS BEEN SCOURED OUT. ENDED
PRECIPITATION BY LATE IN THE NIGHT AND THAT MAY BE TOO LATE.
WILL GET SOME FOG AND STRATUS IN THE NORTHWEST PORTION OF THE AREA
AS THE FRONT MOVES THROUGH. WITH AN EARLIER FRONTAL ARRIVAL
EXPECTED...HIGH TEMPERATURES SHOULD BE COOLER BUT AM NOT CERTAIN
ABOUT THAT.
TUESDAY/TUESDAY NIGHT...LEE TROUGH REDEVELOPS/STRENGTHENS AS
STRONGER SHORTWAVE STARTS APPROACHING FROM THE WEST. MAIN SURFACE
CONVERGENCE REMAINS TO THE WEST OF THE AREA THROUGH THE DAY.
SURFACE BOUNDARY DOES NOT MOVE INTO THE AREA UNTIL LATER IN THE
NIGHT. PLUS MAIN LIFT DOES NOT ARRIVE UNTIL DURING THE NIGHT AS
WELL. SO HAVE SLIGHT CHANCE DURING THE AFTERNOON WITH THE MAIN
CHANCE OF PRECIPITATION DURING THE NIGHT. WITH STRENGTHENING
EASTERLY WINDS DURING THE DAY...AM THINKING THAT CURRENT MAX
TEMPERATURES WILL NEED TO BE COOLED SOME WAS NOT ABLE TO SPEND A LOT
OF TIME ON THAT.
WEDNESDAY/WEDNESDAY NIGHT...MODELS MOVE/DEVELOP A LEFT FRONT QUADRANT
OF THE JET OVER THE CENTRAL/EASTERN PORTION OF THE AREA DURING THE
AFTERNOON. THEN MODELS DIFFER ON HOW THEY MOVE IT. SOME MOVE IT EAST
OF THE AREA BY LATE AFTERNOON WITH OTHERS KEEPING IT THERE. THEN
THE SLOWER MODELS MOVE IT EAST OF THE AREA DURING THE EVENING.
MODELS DIFFER ON THE SPEED IN WHICH THEY TAKE THE NEXT BOUNDARY
THROUGH. IF THIS IS SLOWER THEN BETTER PRECIPITATION CHANCES WILL
NEED TO BE PULLED BACK SLOWER. DID SIDE WITH THE SLOWER ARRIVAL BUT
THIS WILL NEED TO BE LOOKED AT. MAIN MID LEVEL LIFT ARRIVES IN THE
AFTERNOON AND EVENING. ALL THIS POINTS TO GOOD CHANCES OF
PRECIPITATION LATER IN THE DAY INTO THE EVENING...ESPECIALLY FOR
THE EASTERN PORTION OF THE AREA. NOT SURE ABOUT WHAT THE
TEMPERATURES WILL DO WITH THE DIFFERENCE IN THE BOUNDARY POSITIONS.
.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 435 AM MDT MON MAY 27 2013
MODELS ARE IN A LITTLE BETTER AGREEMENT WITH MOVEMENT OF UPPER
LOW/TROUGH...MINOR DIFFERENCES IN PLACEMENT OF UPPER LOW/TROUGH
EXIST. THE GFS HAS THE UPPER LOW OVER THE NORTHERN ROCKIES MOVING
EAST AND THE ADJACENT SURFACE LOW OVER THE DAKOTAS ON THURSDAY AND
FRIDAY. THE ECMWF PLACES THE UPPER LOW/TROUGH SLIGHTLY FURTHER NORTH
AND WEST...WHICH IS SLOWER MOVING EAST BUT SHOULD NOT AFFECT THE
TIMING OF THE MAIN FEATURES TOO MUCH. AS THE SURFACE LOW AND UPPER
LOW MOVE EAST...A COLD FRONT WILL SWING THROUGH THE CWA THURSDAY
MORNING. COLD AIR ALOFT WILL FILTER IN BEHIND THE FRONT...THIS
COMBINED WITH VORTICITY WRAPPING AROUND THE UPPER LOW AND SOME MINOR
INSTABILITY WILL BRING A CHANCE FOR SHOWERS AND TSTORMS ON THURSDAY
AFTERNOON. THE UPPER LOW STARTS TO PULL AWAY FROM THE CWA ON FRIDAY
LEAVING SOME LINGERING CLOUDS AND ON SATURDAY CONDITIONS WILL BECOME
CLEAR AS HIGH PRESSURE MOVES INTO THE CWA. MORE SEASONABLE
TEMPERATURES IN THE MID TO UPPER 70S WILL OCCUR ON FRIDAY AND
SATURDAY. SOUTHERLY RETURN FLOW SETS UP ON SUNDAY AFTERNOON OVER THE
CWA AND THE GFS HAS LOW AMPLITUDE RIDGING OVER THE CWA WITH EMBEDDED
SHORTWAVES MOVING THROUGH COLORADO WHILE THE ECMWF HAS ZONAL FLOW
OVER THE CENTRAL PLAINS. POPS WERE LEFT OUT OF SUNDAY FOR NOW...THIS
MAY CHANGE DEPENDING ON HOW MODELS RESOLVE THEIR DIFFERENCES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 538 AM MDT MON MAY 27 2013
VFR CONDITIONS ARE EXPECTED THROUGH MOST OF THE PERIOD. SHOWERS
AND THUNDERSTORMS ARE POSSIBLE ONCE AGAIN AT BOTH TAF SITES DUE
TO A SURFACE LOW OVER COLORADO MOVING EAST. MVF CONDITIONS COULD
BE POSSIBLE TUESDAY MORNING DUE TO LOW STRATUS...BUT GIVEN THE
TREND OVER THE PAST FEW DAYS...NOT SURE HOW THAT WILL PAN OUT.
&&
.FIRE WEATHER...
ISSUED AT 435 AM MDT MON MAY 27 2013
FOR TODAY...DUE TO THE FRONT MOVING IN FASTER...IT LOOKS LIKE THE
AREA WILL ESCAPE ANY FIRE WEATHER ISSUES. IF FRONT DOES SLOW UP...
GREELEY AND WICHITA COULD REACH CRITERIA.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...BULLER
LONG TERM...ALW
AVIATION...BULLER/ALW
FIRE WEATHER...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
545 AM MDT MON MAY 27 2013
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 435 AM MDT MON MAY 27 2013
MAIN FORECAST PROBLEM WILL BE CONTINUED CHANCES FOR THUNDERSTORMS.
SATELLITE SHOWING THE FLOW HAS DEAMPLIFIED OVER THE PACIFIC AND THE
PACIFIC NORTHWEST. WHAT USED TO BE A COMPLEX UPPER LOW OVER THE
PACIFIC NORTHWEST HAS NOW BEEN SPLIT APART WITH THE SOUTHERN
PORTION COMING EAST NOW AS AN OPEN SHORTWAVE TROUGH. WITH WEAKENING
MID LEVEL RIDGE TO OUR EAST...THIS LEAVES OUR AREA IN A SOUTHWEST
FLOW ALOFT WITH NUMEROUS SMALL SCALE SHORTWAVE TROUGHS EMBEDDED
WITHIN IT. A COMPLEX SURFACE PATTERN IS OVER THE AREA WITH A
RETREATING WARM FRONT OVER THE NORTHWEST PORTION OF THE AREA WHICH
IS EXTENDING FROM THE SURFACE LOW OVER SOUTHEAST COLORADO. THE DRY
LINE IS JUST TO THE EAST OF THAT. A SHALLOWER/COOLER AIR MASS IS TO
THE NORTH OF THIS WARM FRONT.
MODELS INITIALIZED WELL AT JET LEVEL. MODELS DID FINE AT MID LEVELS
WITH THE GFS...CANADIAN AND UKMET DOING THE BEST ON THE HEIGHTS AND
FEATURES. THE MODELS WERE WARM AT 700 MB WITH THE CANADIAN DOING
THE BEST. MODELS HAVING HARD TIME WITH THE SURFACE PATTERN. MAJORITY
HAVE THE SURFACE LOW THAT STARTS OUT OVER SOUTHEAST COLORADO TOO
FAR EAST BY 06Z. THE ECMWF AND RUC DEFINITELY IS HEAD AND SHOULDERS
ABOVE THE REST. WOULD ALSO HAVE TO GIVE THE ECMWF A SLIGHT EDGE ON
THE THERMAL FIELD AS WELL.
BASED ON RECENT POOR MODEL PERFORMANCE...COMPLEX NATURE OF SURFACE
PATTERN...AND CONVECTIVE FEEDBACK ISSUES WITH THE MODELS...THIS IS
A LOW CONFIDENCE FORECAST. THIS COMPOUNDED BY THE FACT THAT CERTAIN
NEIGHBORING OFFICES ARE MAKING BIG CHANGES WITHOUT TALKING.
TODAY/TONIGHT...SOME CONVECTION HAS DEVELOPED NORTH OF THE
RETREATING WARM FRONT WITH OTHER CONVECTION ON THE WESTWARD
EXTENSION OF THIS WEAVING/COMPLEX FRONTAL POSITION. RECENT TRENDS
AND MESOSCALE MODEL OUTPUT INDICATE ALL THIS PRECIPITATION WILL STAY
TO THE NORTH OF THE AREA. BUT WILL CONTINUE TO MONITOR.
LEFT FRONT QUADRANT OF THE JET STARTS OVER THE SOUTHERN PORTION OF
THE AREA AT 12Z AND IS AFFECTING/OVER THE NORTHERN PORTION OF THE
AREA BY THE END OF THE DAY. THIS FEATURE THEN MOVES SOUTHEAST DURING
THE NIGHT. RIGHT NOW THE MODELS ARE HAVING EXTREME DIFFICULTIES IN
RESOLVING BOUNDARY POSITION AND TIMING. MODELS TAKE A COMPACT 700
MB LOW OVER COLORADO AND MOVE IN TO THE NORTH OF THE AREA BY EARLY
AFTERNOON. DEPENDING ON WHICH MODEL OUTPUT YOU USE...SOME
WRAPAROUND OCCURS WITH THIS. CONSIDERING THE TRAJECTORY...AM NOT
BUYING IT. WITH THE JET...SURFACE BOUNDARY POSITION AND THIS
SYSTEM...BEST CHANCES FOR PRECIPITATION SHOULD BE IN THE NORTH AND
END BY LATE IN THE AFTERNOON. ADDITIONAL SHORTWAVE ENERGY MOVES
THROUGH DURING THE NIGHT BUT MOISTURE HAS BEEN SCOURED OUT. ENDED
PRECIPITATION BY LATE IN THE NIGHT AND THAT MAY BE TOO LATE.
WILL GET SOME FOG AND STRATUS IN THE NORTHWEST PORTION OF THE AREA
AS THE FRONT MOVES THROUGH. WITH AN EARLIER FRONTAL ARRIVAL
EXPECTED...HIGH TEMPERATURES SHOULD BE COOLER BUT AM NOT CERTAIN
ABOUT THAT.
TUESDAY/TUESDAY NIGHT...LEE TROUGH REDEVELOPS/STRENGTHENS AS
STRONGER SHORTWAVE STARTS APPROACHING FROM THE WEST. MAIN SURFACE
CONVERGENCE REMAINS TO THE WEST OF THE AREA THROUGH THE DAY.
SURFACE BOUNDARY DOES NOT MOVE INTO THE AREA UNTIL LATER IN THE
NIGHT. PLUS MAIN LIFT DOES NOT ARRIVE UNTIL DURING THE NIGHT AS
WELL. SO HAVE SLIGHT CHANCE DURING THE AFTERNOON WITH THE MAIN
CHANCE OF PRECIPITATION DURING THE NIGHT. WITH STRENGTHENING
EASTERLY WINDS DURING THE DAY...AM THINKING THAT CURRENT MAX
TEMPERATURES WILL NEED TO BE COOLED SOME WAS NOT ABLE TO SPEND A LOT
OF TIME ON THAT.
WEDNESDAY/WEDNESDAY NIGHT...MODELS MOVE/DEVELOP A LEFT FRONT QUADRANT
OF THE JET OVER THE CENTRAL/EASTERN PORTION OF THE AREA DURING THE
AFTERNOON. THEN MODELS DIFFER ON HOW THEY MOVE IT. SOME MOVE IT EAST
OF THE AREA BY LATE AFTERNOON WITH OTHERS KEEPING IT THERE. THEN
THE SLOWER MODELS MOVE IT EAST OF THE AREA DURING THE EVENING.
MODELS DIFFER ON THE SPEED IN WHICH THEY TAKE THE NEXT BOUNDARY
THROUGH. IF THIS IS SLOWER THEN BETTER PRECIPITATION CHANCES WILL
NEED TO BE PULLED BACK SLOWER. DID SIDE WITH THE SLOWER ARRIVAL BUT
THIS WILL NEED TO BE LOOKED AT. MAIN MID LEVEL LIFT ARRIVES IN THE
AFTERNOON AND EVENING. ALL THIS POINTS TO GOOD CHANCES OF
PRECIPITATION LATER IN THE DAY INTO THE EVENING...ESPECIALLY FOR
THE EASTERN PORTION OF THE AREA. NOT SURE ABOUT WHAT THE
TEMPERATURES WILL DO WITH THE DIFFERENCE IN THE BOUNDARY POSITIONS.
.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 435 AM MDT MON MAY 27 2013
MODELS ARE IN A LITTLE BETTER AGREEMENT WITH MOVEMENT OF UPPER
LOW/TROUGH...MINOR DIFFERENCES IN PLACEMENT OF UPPER LOW/TROUGH
EXIST. THE GFS HAS THE UPPER LOW OVER THE NORTHERN ROCKIES MOVING
EAST AND THE ADJACENT SURFACE LOW OVER THE DAKOTAS ON THURSDAY AND
FRIDAY. THE ECMWF PLACES THE UPPER LOW/TROUGH SLIGHTLY FURTHER NORTH
AND WEST...WHICH IS SLOWER MOVING EAST BUT SHOULD NOT AFFECT THE
TIMING OF THE MAIN FEATURES TOO MUCH. AS THE SURFACE LOW AND UPPER
LOW MOVE EAST...A COLD FRONT WILL SWING THROUGH THE CWA THURSDAY
MORNING. COLD AIR ALOFT WILL FILTER IN BEHIND THE FRONT...THIS
COMBINED WITH VORTICITY WRAPPING AROUND THE UPPER LOW AND SOME MINOR
INSTABILITY WILL BRING A CHANCE FOR SHOWERS AND TSTORMS ON THURSDAY
AFTERNOON. THE UPPER LOW STARTS TO PULL AWAY FROM THE CWA ON FRIDAY
LEAVING SOME LINGERING CLOUDS AND ON SATURDAY CONDITIONS WILL BECOME
CLEAR AS HIGH PRESSURE MOVES INTO THE CWA. MORE SEASONABLE
TEMPERATURES IN THE MID TO UPPER 70S WILL OCCUR ON FRIDAY AND
SATURDAY. SOUTHERLY RETURN FLOW SETS UP ON SUNDAY AFTERNOON OVER THE
CWA AND THE GFS HAS LOW AMPLITUDE RIDGING OVER THE CWA WITH EMBEDDED
SHORTWAVES MOVING THROUGH COLORADO WHILE THE ECMWF HAS ZONAL FLOW
OVER THE CENTRAL PLAINS. POPS WERE LEFT OUT OF SUNDAY FOR NOW...THIS
MAY CHANGE DEPENDING ON HOW MODELS RESOLVE THEIR DIFFERENCES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 538 AM MDT MON MAY 27 2013
VFR CONDITIONS ARE EXPECTED THROUGH MOST OF THE PERIOD. SHOWERS
AND THUNDERSTORMS ARE POSSIBLE ONCE AGAIN AT BOTH TAF SITES DUE
TO A SURFACE LOW OVER COLORADO MOVING EAST. MVF CONDITIONS COULD
BE POSSIBLE TUESDAY MORNING DUE TO LOW STRATUS...BUT GIVEN THE
TREND OVER THE PAST FEW DAYS...NOT SURE HOW THAT WILL PAN OUT.
&&
.FIRE WEATHER...
ISSUED AT 435 AM MDT MON MAY 27 2013
FOR TODAY...DUE TO THE FRONT MOVING IN FASTER...IT LOOKS LIKE THE
AREA WILL ESCAPE ANY FIRE WEATHER ISSUES. IF FRONT DOES SLOW UP...
GREELEY AND WICHITA COULD REACH CRITERIA.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...ALW
AVIATION...BULLER/ALW
FIRE WEATHER...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
435 AM MDT MON MAY 27 2013
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 435 AM MDT MON MAY 27 2013
MAIN FORECAST PROBLEM WILL BE CONTINUED CHANCES FOR THUNDERSTORMS.
SATELLITE SHOWING THE FLOW HAS DEAMPLIFIED OVER THE PACIFIC AND THE
PACIFIC NORTHWEST. WHAT USED TO BE A COMPLEX UPPER LOW OVER THE
PACIFIC NORTHWEST HAS NOW BEEN SPLIT APART WITH THE SOUTHERN
PORTION COMING EAST NOW AS AN OPEN SHORTWAVE TROUGH. WITH WEAKENING
MID LEVEL RIDGE TO OUR EAST...THIS LEAVES OUR AREA IN A SOUTHWEST
FLOW ALOFT WITH NUMEROUS SMALL SCALE SHORTWAVE TROUGHS EMBEDDED
WITHIN IT. A COMPLEX SURFACE PATTERN IS OVER THE AREA WITH A
RETREATING WARM FRONT OVER THE NORTHWEST PORTION OF THE AREA WHICH
IS EXTENDING FROM THE SURFACE LOW OVER SOUTHEAST COLORADO. THE DRY
LINE IS JUST TO THE EAST OF THAT. A SHALLOWER/COOLER AIR MASS IS TO
THE NORTH OF THIS WARM FRONT.
MODELS INITIALIZED WELL AT JET LEVEL. MODELS DID FINE AT MID LEVELS
WITH THE GFS...CANADIAN AND UKMET DOING THE BEST ON THE HEIGHTS AND
FEATURES. THE MODELS WERE WARM AT 700 MB WITH THE CANADIAN DOING
THE BEST. MODELS HAVING HARD TIME WITH THE SURFACE PATTERN. MAJORITY
HAVE THE SURFACE LOW THAT STARTS OUT OVER SOUTHEAST COLORADO TOO
FAR EAST BY 06Z. THE ECMWF AND RUC DEFINITELY IS HEAD AND SHOULDERS
ABOVE THE REST. WOULD ALSO HAVE TO GIVE THE ECMWF A SLIGHT EDGE ON
THE THERMAL FIELD AS WELL.
BASED ON RECENT POOR MODEL PERFORMANCE...COMPLEX NATURE OF SURFACE
PATTERN...AND CONVECTIVE FEEDBACK ISSUES WITH THE MODELS...THIS IS
A LOW CONFIDENCE FORECAST. THIS COMPOUNDED BY THE FACT THAT CERTAIN
NEIGHBORING OFFICES ARE MAKING BIG CHANGES WITHOUT TALKING.
TODAY/TONIGHT...SOME CONVECTION HAS DEVELOPED NORTH OF THE
RETREATING WARM FRONT WITH OTHER CONVECTION ON THE WESTWARD
EXTENSION OF THIS WEAVING/COMPLEX FRONTAL POSITION. RECENT TRENDS
AND MESOSCALE MODEL OUTPUT INDICATE ALL THIS PRECIPITATION WILL STAY
TO THE NORTH OF THE AREA. BUT WILL CONTINUE TO MONITOR.
LEFT FRONT QUADRANT OF THE JET STARTS OVER THE SOUTHERN PORTION OF
THE AREA AT 12Z AND IS AFFECTING/OVER THE NORTHERN PORTION OF THE
AREA BY THE END OF THE DAY. THIS FEATURE THEN MOVES SOUTHEAST DURING
THE NIGHT. RIGHT NOW THE MODELS ARE HAVING EXTREME DIFFICULTIES IN
RESOLVING BOUNDARY POSITION AND TIMING. MODELS TAKE A COMPACT 700
MB LOW OVER COLORADO AND MOVE IN TO THE NORTH OF THE AREA BY EARLY
AFTERNOON. DEPENDING ON WHICH MODEL OUTPUT YOU USE...SOME
WRAPAROUND OCCURS WITH THIS. CONSIDERING THE TRAJECTORY...AM NOT
BUYING IT. WITH THE JET...SURFACE BOUNDARY POSITION AND THIS
SYSTEM...BEST CHANCES FOR PRECIPITATION SHOULD BE IN THE NORTH AND
END BY LATE IN THE AFTERNOON. ADDITIONAL SHORTWAVE ENERGY MOVES
THROUGH DURING THE NIGHT BUT MOISTURE HAS BEEN SCOURED OUT. ENDED
PRECIPITATION BY LATE IN THE NIGHT AND THAT MAY BE TOO LATE.
WILL GET SOME FOG AND STRATUS IN THE NORTHWEST PORTION OF THE AREA
AS THE FRONT MOVES THROUGH. WITH AN EARLIER FRONTAL ARRIVAL
EXPECTED...HIGH TEMPERATURES SHOULD BE COOLER BUT AM NOT CERTAIN
ABOUT THAT.
TUESDAY/TUESDAY NIGHT...LEE TROUGH REDEVELOPS/STRENGTHENS AS
STRONGER SHORTWAVE STARTS APPROACHING FROM THE WEST. MAIN SURFACE
CONVERGENCE REMAINS TO THE WEST OF THE AREA THROUGH THE DAY.
SURFACE BOUNDARY DOES NOT MOVE INTO THE AREA UNTIL LATER IN THE
NIGHT. PLUS MAIN LIFT DOES NOT ARRIVE UNTIL DURING THE NIGHT AS
WELL. SO HAVE SLIGHT CHANCE DURING THE AFTERNOON WITH THE MAIN
CHANCE OF PRECIPITATION DURING THE NIGHT. WITH STRENGTHENING
EASTERLY WINDS DURING THE DAY...AM THINKING THAT CURRENT MAX
TEMPERATURES WILL NEED TO BE COOLED SOME WAS NOT ABLE TO SPEND A LOT
OF TIME ON THAT.
WEDNESDAY/WEDNESDAY NIGHT...MODELS MOVE/DEVELOP A LEFT FRONT QUADRANT
OF THE JET OVER THE CENTRAL/EASTERN PORTION OF THE AREA DURING THE
AFTERNOON. THEN MODELS DIFFER ON HOW THEY MOVE IT. SOME MOVE IT EAST
OF THE AREA BY LATE AFTERNOON WITH OTHERS KEEPING IT THERE. THEN
THE SLOWER MODELS MOVE IT EAST OF THE AREA DURING THE EVENING.
MODELS DIFFER ON THE SPEED IN WHICH THEY TAKE THE NEXT BOUNDARY
THROUGH. IF THIS IS SLOWER THEN BETTER PRECIPITATION CHANCES WILL
NEED TO BE PULLED BACK SLOWER. DID SIDE WITH THE SLOWER ARRIVAL BUT
THIS WILL NEED TO BE LOOKED AT. MAIN MID LEVEL LIFT ARRIVES IN THE
AFTERNOON AND EVENING. ALL THIS POINTS TO GOOD CHANCES OF
PRECIPITATION LATER IN THE DAY INTO THE EVENING...ESPECIALLY FOR
THE EASTERN PORTION OF THE AREA. NOT SURE ABOUT WHAT THE
TEMPERATURES WILL DO WITH THE DIFFERENCE IN THE BOUNDARY POSITIONS.
.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 435 AM MDT MON MAY 27 2013
MODELS ARE IN A LITTLE BETTER AGREEMENT WITH MOVEMENT OF UPPER
LOW/TROUGH...MINOR DIFFERENCES IN PLACEMENT OF UPPER LOW/TROUGH
EXIST. THE GFS HAS THE UPPER LOW OVER THE NORTHERN ROCKIES MOVING
EAST AND THE ADJACENT SURFACE LOW OVER THE DAKOTAS ON THURSDAY AND
FRIDAY. THE ECMWF PLACES THE UPPER LOW/TROUGH SLIGHTLY FURTHER NORTH
AND WEST...WHICH IS SLOWER MOVING EAST BUT SHOULD NOT AFFECT THE
TIMING OF THE MAIN FEATURES TOO MUCH. AS THE SURFACE LOW AND UPPER
LOW MOVE EAST...A COLD FRONT WILL SWING THROUGH THE CWA THURSDAY
MORNING. COLD AIR ALOFT WILL FILTER IN BEHIND THE FRONT...THIS
COMBINED WITH VORTICITY WRAPPING AROUND THE UPPER LOW AND SOME MINOR
INSTABILITY WILL BRING A CHANCE FOR SHOWERS AND TSTORMS ON THURSDAY
AFTERNOON. THE UPPER LOW STARTS TO PULL AWAY FROM THE CWA ON FRIDAY
LEAVING SOME LINGERING CLOUDS AND ON SATURDAY CONDITIONS WILL BECOME
CLEAR AS HIGH PRESSURE MOVES INTO THE CWA. MORE SEASONABLE
TEMPERATURES IN THE MID TO UPPER 70S WILL OCCUR ON FRIDAY AND
SATURDAY. SOUTHERLY RETURN FLOW SETS UP ON SUNDAY AFTERNOON OVER THE
CWA AND THE GFS HAS LOW AMPLITUDE RIDGING OVER THE CWA WITH EMBEDDED
SHORTWAVES MOVING THROUGH COLORADO WHILE THE ECMWF HAS ZONAL FLOW
OVER THE CENTRAL PLAINS. POPS WERE LEFT OUT OF SUNDAY FOR NOW...THIS
MAY CHANGE DEPENDING ON HOW MODELS RESOLVE THEIR DIFFERENCES.
&&
.AVIATION....(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1132 PM MDT SUN MAY 26 2013
SOME GUIDANCE CONTINUES TO SUPPORT FOG DEVELOPMENT ACROSS
SOUTHWEST NEBRASKA SPREADING SOUTH TOWARDS THE I-70 CORRIDOR AFTER
09Z WITH BEST CHANCE FOR FOG IN THE 11-15Z TIMEFRAME. CURRENT
SURFACE PATTERN COMPLICATED BY SEVERAL FRONTS AND SURFACE TROUGH
IN PROXIMITY TO BOTH TERMINALS...AND POSSIBLE OUTFLOW MOVING
SOUTH/SOUTHEAST FROM CENTRAL NEBRASKA. SHORT RANGE GUIDANCE IS
DOING A LITTLE BETTER WITH THIS AND IS MUCH LESS FAVORABLE FOR
FOG/STRATUS AT KGLD...THOUGH IT DOES STILL SUPPORT SOME
FOG/STRATUS NEAR KMCK. IN ADDITION SHOWERS/THUNDERSTORMS HAVE
DEVELOPED LATE THIS EVENING OVER SW NEBRASKA JUST NORTH OF WARM
FRONT.
I DECIDED TO ADD VCSH TO KMCK THROUGH THE EARLY TAF
PERIOD TO COVER CURRENT TRENDS AND BROUGHT TEMPO IFR CIG/VIS IN
THE 11-14Z TIMEFRAME FOR WHEN BEST CHANCE OF FOG IS (CONFIDENCE IN
PREVAILING IS STILL LOW). I AM MORE CONFIDENT IN PREVAILING VFR
FOR KGLD...THOUGH WILL HAVE TO MONITOR CURRENT TRENDS.
THUNDERSTORMS WILL BE POSSIBLE OVERNIGHT AND AGAIN MONDAY
AFTERNOON/EVENING...HOWEVER COVERAGE IS A BIG QUESTION AND I
DECIDED AGAINST KEEPING MENTION IN TAFS FOR NOW.
&&
.FIRE WEATHER...
ISSUED AT 435 AM MDT MON MAY 27 2013
FOR TODAY...DUE TO THE FRONT MOVING IN FASTER...IT LOOKS LIKE THE
AREA WILL ESCAPE ANY FIRE WEATHER ISSUES. IF FRONT DOES SLOW UP...
GREELEY AND WICHITA COULD REACH CRITERIA.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...ALW
AVIATION...DR
FIRE WEATHER...BULLER
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
625 PM EDT MON MAY 27 2013
.UPDATE...
ISSUED AT 625 PM EDT MON MAY 27 2013
NO PCPN WITHIN THE STATE AND THE STORMS IN ILL ARE EITHER MOVING
NORTH OR THE SOUTH END IS DISSIPATING. NEW MODELS INDICATE THE PCPN
WILL MOVE ACROSS IND/OH TO OUR NORTH BUT NOT INTO ERN KY DUE TO A
SIGNIFICANT LOW LEVEL RIDGE EXTENDING INTO THE COMMONWEALTH FROM THE
SOUTHERN ATLANTIC COAST. SWRN WINDS ARE STILL BREEZY BUT SHOULD
DIMINISH WITH THE SETTING SUN. WILL FURTHER UPDATE WHEN WINDS
DECREASE.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 310 PM EDT MON MAY 27 2013
A WARM FRONT CONTINUES TO LIFT TO THE NORTH AND EAST OUT OF THE CWA
AND AS OF 3 PM WAS LOCATED FROM SOUTHEASTERN INDIANA EAST INTO
SOUTHERN OH AND THEN SOUTHEAST INTO THE WV COALFIELDS. AS OF MID
AFTERNOON...A RATHER ZONAL PATTERN WAS IN PLACE ACROSS MUCH OF THE
CONUS WITH A TROUGH WORKING INTO THE WEST COAST OF THE CONUS...AND A
SHORTWAVE TROUGH MOVING ACROSS THE UPPER MS VALLEY WHILE A DEEP
TROUGH CONTINUES TO WORK THROUGH THE CANADIAN MARITIMES.
THE SHORTWAVE TROUGH OVER THE UPPER MS VALLEY WILL MOVE INTO THE
NORTHERN GREAT LAKES TONIGHT AND INTO THE DAY ON TUE WITH RIDING
GRADUALLY BUILDING ACROSS THE SOUTHEASTERN STATES AND SOUTHERN
APPALACHIANS THROUGH THE END OF THE PERIOD.
GENERALLY FLAT CU HAS DEVELOPED SO FAR OVER THE JKL CWA BUT WITH
DEWPOINTS IN THE UPPER 50S NEAR THE VICINITY AND JUST BEHIND THE WARM
FRONT SOME ISOLATED SHRA AND OR TSRA CANNOT BE RULED OUT THROUGH THIS
EVENING. CU SHOULD DISSIPATE AS WE MOVE TOWARD SUNSET...BUT AT LEAST
SOME DEBRIS CLOUDS FROM CONVECTION NOW OVER THE MS VALLEY SHOULD
EVENTUALLY WORK ACROSS THE REGION TONIGHT. IT WOULD SEEM THAT DRIER
AIR OVER MUCH OF KY DOWN IN THE TN VALLEY SHOULD LEAD TO THE SOUTHERN
END OF THIS COMPLEX WEAKENING AS IT WORKS EAST THIS EVENING AND INTO
THE OVERNIGHT. THE LATEST HRRR HANDLING OF IT SEEMS MOST REASONABLE
AND THE 12Z NAM SEEMS TO BE OVERDOING CONVECTION ATTM IN THE LOWER OH
VALLEY EAST OF THE COMPLEX OVER MO AND IL. THE GFS ALSO HAS SOME LATE
NIGHT CONVECTION OVER THE CWA AS WELL. THE 12Z ECMWF KEEPS ALL THE
ACTION CLOSER TO THE WARM FRONT. OPTED TO GO WITH SOME SLIGHT CHANCES
MAINLY THIS EVENING ACROSS THE NORTH...NORTH OF THE MTN PARKWAY..BUT
CONFIDENCE IN THIS IS NOT HIGH.
MOISTURE SHOULD REMAIN LIMITED AND AT THIS POINT ANY TRIGGERS HARD TO
DISCERN FOR CONVECTION ON TUE. THERE MAY BE A WEAK SHORTWAVE OR TO
WORKING AROUND THE RIDGE...BUT WITH HEIGHTS PROGGED TO RISE ON TUE
INTO TUE NIGHT...WE HAVE OPTED TO GO WITH A DRY FORECAST FOR TUE.
TEMPERATURES SHOULD MODERATE FURTHER ON TUE...INTO THE MID TO UPPER
80S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 300 PM EDT MON MAY 27 2013
RIDGING WILL HOLD OVER THE EASTERN US THROUGH THE END OF THE WEEK.
THIS WILL KEEP OUR AREA WEST OF THE HIGH PRESSURE AREA IN AN AREA OF
RETURN FLOW. THIS WILL LEAD TO AN EXTENDED PERIOD OF MILD NIGHTS AND
WARM DAYS. INSTABILITY WILL GREATLY INCREASE FROM WEDNESDAY ONWARD
DURING THE DAYLIGHT HOURS...BUT WE WILL BE LACKING ANY TRIGGERS.
MODELS ARE STILL LIKELY OVER AGGRESSIVE WITH THE AMOUNT OF SURFACE
MOISTURE EACH DAY...SO LIKELY OVERDOING THE CAPE. HOWEVER...SOME
GOOD CU FIELDS SHOULD DEVELOP EACH AFTERNOON...AND IT MAY BE
POSSIBLE TO POP A VERY ISOLATED SHOWER OR STORM ALONG THE HIGHER
RIDES IN THE SOUTHEAST EACH AFTERNOON FROM WEDNESDAY THROUGH FRIDAY.
EACH DAY SHOULD FEATURE A SLIGHT BETTER CHANCE OF THIS HAPPENING AS
DEWPOINTS SHOULD CONTINUE TO INCH UP THROUGH THE REMAINDER OF THE
WEEK.
BY THIS WEEKEND...HIGH PRESSURE WILL RELINQUISH ITS HOLD ON THE AREA
AS A MID LEVEL SHORTWAVE APPROACHES FROM THE WEST. INCREASING FLOW
AHEAD OF THIS FEATURE ON SATURDAY...COULD YIELD A BETTER SHOT OF AN
ISOLATED SHOWER OR STORM BY SATURDAY AFTERNOON. THE CHANCES FOR
SHOWERS AND STORMS WILL INCREASE HEADING INTO SUNDAY AS THIS TROUGH
PUSHES EAST ACROSS THE AREA. PRESENTLY...MODELS IN FAIRLY GOOD
AGREEMENT ON TIMING...SO CONFIDENCE REMAINS HIGHER THAN NORMAL FOR
DAY 7. WITH THE FRONTAL PASSAGE...SLIGHTLY COOLER WEATHER SHOULD
RETURN TO THE AREA BY EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 230 PM EDT MON MAY 27 2013
VFR CONDITIONS SHOULD PREVAIL THROUGHOUT THE TAF PERIOD AT ALL THREE
AIRPORTS. ISOLATED SHOWERS AND STORMS COULD AFFECT JKL THROUGH AROUND
0Z. OTHERWISE...CU NEAR 5 TO 6KFT SHOULD CONTINUE TO DEVELOP OVER THE
NEXT TWO TO THREE HOURS...BEFORE DIMINISHING. WITH THE WARM FRONT NOW
MOVING INTO WV...WINDS WILL AVERAGE OUT OF THE SOUTH SOUTHWEST TO
SOUTHWEST. WINDS WILL SLACKEN OVERNIGHT...BEFORE PICKING UP AT NEAR
10KT...ESPECIALLY LOZ AND SME AFTER 15Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DUSTY
SHORT TERM...JP
LONG TERM...KAS
AVIATION...JP
AREA FORECAST DISCUSSION
NWS JACKSON KY
320 PM EDT MON MAY 27 2013
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 310 PM EDT MON MAY 27 2013
A WARM FRONT CONTINUES TO LIFT TO THE NORTH AND EAST OUT OF THE CWA
AND AS OF 3 PM WAS LOCATED FROM SOUTHEASTERN INDIANA EAST INTO
SOUTHERN OH AND THEN SOUTHEAST INTO THE WV COALFIELDS. AS OF MID
AFTERNOON...A RATHER ZONAL PATTERN WAS IN PLACE ACROSS MUCH OF THE
CONUS WITH A TROUGH WORKING INTO THE WEST COAST OF THE CONUS...AND A
SHORTWAVE TROUGH MOVING ACROSS THE UPPER MS VALLEY WHILE A DEEP
TROUGH CONTINUES TO WORK THROUGH THE CANADIAN MARITIMES.
THE SHORTWAVE TROUGH OVER THE UPPER MS VALLEY WILL MOVE INTO THE
NORTHERN GREAT LAKES TONIGHT AND INTO THE DAY ON TUE WITH RIDING
GRADUALLY BUILDING ACROSS THE SOUTHEASTERN STATES AND SOUTHERN
APPALACHIANS THROUGH THE END OF THE PERIOD.
GENERALLY FLAT CU HAS DEVELOPED SO FAR OVER THE JKL CWA BUT WITH
DEWPOINTS IN THE UPPER 50S NEAR THE VICINITY AND JUST BEHIND THE WARM
FRONT SOME ISOLATED SHRA AND OR TSRA CANNOT BE RULED OUT THROUGH THIS
EVENING. CU SHOULD DISSIPATE AS WE MOVE TOWARD SUNSET...BUT AT LEAST
SOME DEBRIS CLOUDS FROM CONVECTION NOW OVER THE MS VALLEY SHOULD
EVENTUALLY WORK ACROSS THE REGION TONIGHT. IT WOULD SEEM THAT DRIER
AIR OVER MUCH OF KY DOWN IN THE TN VALLEY SHOULD LEAD TO THE SOUTHERN
END OF THIS COMPLEX WEAKENING AS IT WORKS EAST THIS EVENING AND INTO
THE OVERNIGHT. THE LATEST HRRR HANDLING OF IT SEEMS MOST REASONABLE
AND THE 12Z NAM SEEMS TO BE OVERDOING CONVECTION ATTM IN THE LOWER OH
VALLEY EAST OF THE COMPLEX OVER MO AND IL. THE GFS ALSO HAS SOME LATE
NIGHT CONVECTION OVER THE CWA AS WELL. THE 12Z ECMWF KEEPS ALL THE
ACTION CLOSER TO THE WARM FRONT. OPTED TO GO WITH SOME SLIGHT CHANCES
MAINLY THIS EVENING ACROSS THE NORTH...NORTH OF THE MTN PARKWAY..BUT
CONFIDENCE IN THIS IS NOT HIGH.
MOISTURE SHOULD REMAIN LIMITED AND AT THIS POINT ANY TRIGGERS HARD TO
DISCERN FOR CONVECTION ON TUE. THERE MAY BE A WEAK SHORTWAVE OR TO
WORKING AROUND THE RIDGE...BUT WITH HEIGHTS PROGGED TO RISE ON TUE
INTO TUE NIGHT...WE HAVE OPTED TO GO WITH A DRY FORECAST FOR TUE.
TEMPERATURES SHOULD MODERATE FURTHER ON TUE...INTO THE MID TO UPPER
80S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 300 PM EDT MON MAY 27 2013
RIDGING WILL HOLD OVER THE EASTERN US THROUGH THE END OF THE WEEK.
THIS WILL KEEP OUR AREA WEST OF THE HIGH PRESSURE AREA IN AN AREA OF
RETURN FLOW. THIS WILL LEAD TO AN EXTENDED PERIOD OF MILD NIGHTS AND
WARM DAYS. INSTABILITY WILL GREATLY INCREASE FROM WEDNESDAY ONWARD
DURING THE DAYLIGHT HOURS...BUT WE WILL BE LACKING ANY TRIGGERS.
MODELS ARE STILL LIKELY OVER AGGRESSIVE WITH THE AMOUNT OF SURFACE
MOISTURE EACH DAY...SO LIKELY OVERDOING THE CAPE. HOWEVER...SOME
GOOD CU FIELDS SHOULD DEVELOP EACH AFTERNOON...AND IT MAY BE
POSSIBLE TO POP A VERY ISOLATED SHOWER OR STORM ALONG THE HIGHER
RIDES IN THE SOUTHEAST EACH AFTERNOON FROM WEDNESDAY THROUGH FRIDAY.
EACH DAY SHOULD FEATURE A SLIGHT BETTER CHANCE OF THIS HAPPENING AS
DEWPOINTS SHOULD CONTINUE TO INCH UP THROUGH THE REMAINDER OF THE
WEEK.
BY THIS WEEKEND...HIGH PRESSURE WILL RELINQUISH ITS HOLD ON THE AREA
AS A MID LEVEL SHORTWAVE APPROACHES FROM THE WEST. INCREASING FLOW
AHEAD OF THIS FEATURE ON SATURDAY...COULD YIELD A BETTER SHOT OF AN
ISOLATED SHOWER OR STORM BY SATURDAY AFTERNOON. THE CHANCES FOR
SHOWERS AND STORMS WILL INCREASE HEADING INTO SUNDAY AS THIS TROUGH
PUSHES EAST ACROSS THE AREA. PRESENTLY...MODELS IN FAIRLY GOOD
AGREEMENT ON TIMING...SO CONFIDENCE REMAINS HIGHER THAN NORMAL FOR
DAY 7. WITH THE FRONTAL PASSAGE...SLIGHTLY COOLER WEATHER SHOULD
RETURN TO THE AREA BY EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 230 PM EDT MON MAY 27 2013
VFR CONDITIONS SHOULD PREVAIL THROUGHOUT THE TAF PERIOD AT ALL THREE
AIRPORTS. ISOLATED SHOWERS AND STORMS COULD AFFECT JKL THROUGH AROUND
0Z. OTHERWISE...CU NEAR 5 TO 6KFT SHOULD CONTINUE TO DEVELOP OVER THE
NEXT TWO TO THREE HOURS...BEFORE DIMINISHING. WITH THE WARM FRONT NOW
MOVING INTO WV...WINDS WILL AVERAGE OUT OF THE SOUTH SOUTHWEST TO
SOUTHWEST. WINDS WILL SLACKEN OVERNIGHT...BEFORE PICKING UP AT NEAR
10KT...ESPECIALLY LOZ AND SME AFTER 15Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JP
LONG TERM...KAS
AVIATION...JP
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
236 PM EDT MON MAY 27 2013
.UPDATE...
ISSUED AT 230 PM EDT MON MAY 27 2013
THE WARM FRONT CONTINUES TO LIFT NORTH TO THE OH RIVER AND EAST
FURTHER INTO THE WV COALFIELDS. GRIDS WERE FRESHENED UP BASED ON
RECENT OBS AND SAT AND RADAR TRENDS. THE MOST RECENT HRRR GUIDANCE
DOES NOT DEVELOP ANY CONVECTION UNTIL EARLY EVENING WHILE THE NEW GFS
DEVELOPS A BIT OVER THE HIGHER TERRAIN OF THE APPALACHIANS ALSO
THROUGH EARLY EVENING. THE 12Z NAM DEVELOPED SOME CONVECTION IN THE
LOWER OH VALLEY PRIOR TO 18Z AND THIS IS NOT OCCURRING AS ACTIVITY
IS WELL TO THE WEST OVER THE MID MS VALLEY AREA. CONFIDENCE IN MODEL
HANDLING AND EVOLUTION OF ANY CONVECTION THROUGH THIS EVENING IS LOW...
BUT MOST...IF NOT ALL LOCATIONS SHOULD REMAIN DRY THROUGH EVENING.
UPDATE ISSUED AT 1003 AM EDT MON MAY 27 2013
THE NEAR TERM TEMPS...DEWPOINTS AND SKY AS WELL AS POPS WERE ADJUSTED
BASED ON RECENT OBS AS WELL AS SATELLITE AND RADAR TRENDS. TEMPS ARE
WARMING UP RATHER QUICKLY IN THE SOUTHWEST WHERE THE FLOW IS MORE
SOUTHERLY AND THERE ARE FEW IN THE WAY OF CLOUDS BEHIND A NORTHWARD
LIFTING WARM FRONT. THE DIURNAL CLIMO CURVE IN GENERAL IS NOT
CAPTURING THE TEMPERATURE RISE AND OPTED TO GO WITH MORE A MOS
DERIVED TEMP CURVE FOR TODAY. MEANWHILE...A BAND OF CLOUDS IS WORKING
INTO THE SOUTHEASTERN PART OF THE CWA. BEHIND THIS BAND...SKIES
SHOULD BE MOSTLY SUNNY IN ALL AREAS INTO THE EARLY AFTERNOON WHEN CU
MAY BEGIN TO FORM. MODELS...ESPECIALLY THE 6Z NAM APPEARS TO BE TOO
AGGRESSIVE WITH THE INCREASE IN LOW LEVEL MOISTURE AND SFC AND
BOUNDARY LAYER DEWPOINTS WHEN COMPARED TO 12Z RAOB FROM NASHVILLE.
INSTABILITY IN THE 6Z NAM FORECAST SOUNDINGS IS LIKELY OVERDONE AS
DEWPOINTS WILL LIKELY MIX INTO THE LOW TO MID 50S RATHER THAN MID TO
UPPER 50S IN THE 6Z NAM...AND THIS MAY LEAD TO OBSERVED CAPE MUCH AS
1000 J/KG LESS THAN THE 6Z NAM FORECAST SOUNDINGS. THE 11Z HRRR SHOWS
VERY LITTLE CONVECTIVE DEVELOPMENT TODAY WITH CONVECTION GENERALLY
ALONG A CORRIDOR NEAR OR MAINLY NORTH OF THE OH RIVER THEN SOUTHEAST
TOWARD THE CENTRAL APPALACHIANS. THE 11Z HRRR HINTS AT SOME POSSIBLE
DEVELOPMENT NEAR THE WV BORDER AND ITS SCENARIO APPEARS REASONABLE.
FOR THIS UPDATE...CONFINED SLIGHT CHANCE POPS TO THE AFTERNOON INTO
EARLY EVENING AND OVER THE EASTERN THIRD TO HALF OF THE CWA. THE
BOTTOMLINE IS MOST LOCATIONS WILL LIKELY NOT EXPERIENCE ANY
CONVECTION TODAY.
THE 12Z NAM AND 9Z SREF HINT AT SOME CONVECTION THIS EVENING AND
BRING A WEAK SHORTWAVE ACROSS THE AREA. THE 11Z HRRR DOES NOT HAVE
THIS AND CONFIDENCE IN THIS IS NOT HIGH...BUT TRENDS WITH THIS WILL
BE MONITORED AS THE ENTIRE SUITE OF 12Z MODEL RUNS ARRIVE.
UPDATE ISSUED AT 651 AM EDT MON MAY 27 2013
NO MAJOR CHANGES WERE MADE TO THE FORECAST THIS MORNING. RAN THE ESTF
TOOL TO INGEST THE LATEST OBSERVATIONAL DATA AND INTEGRATE IT WITH
THE 4 AM FORECAST DATA. OVERALL THE FORECAST IS ON TRACK SO FAR
TODAY. SCATTERED SHOWERS AND STORMS CONTINUE TO MOVE ACROSS SOUTHERN
INDIANA AND OHIO...WITH A FEW OF THESE OCCASIONALLY STRAYING SOUTH
INTO THE NORTHERN FRINGES OF THE FORECAST AREA. THIS TREND IS
EXPECTED TO CONTINUE FOR THE NEXT SEVERAL HOURS. ACTIVITY IS EXPECTED
TO INCREASE A BIT DURING THE PEAK HEATING OF THE DAY...AS A ILL
DEFINED WARM FRONT MOVES IN FROM THE SOUTHWEST. NO UPDATE IS PLANNED
AT THIS TIME.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 301 AM EDT MON MAY 27 2013
MODELS WERE IN PRETTY GOOD AGREEMENT FOR THE SHORT TERM PORTION OF
THE FORECAST. THE CONSENSUS VIEW IS FOR ISOLATED SHOWERS AND STORMS
TO PUSH JUST TO THE SOUTH OF THE OHIO RIVER TODAY AND AGAIN LATE IN
THE DAY ON TUESDAY. THE LATEST RADAR IMAGERY SHOWED SCATTERED SHOWERS
AND STORMS MOVING ACROSS SOUTHERN INDIANA...NORTH CENTRAL
KENTUCKY...AND SOUTHWESTERN OHIO. A FEW OF THESE MIGHT MAKE INTO THE
NORTHERN MOST AREAS OF THE FORECAST BY EARLY THIS MORNING.
THEREFORE...SLIGHT CHANCE POPS WERE LEFT IN PLACE TO ACCOUNT FOR THIS
POTENTIAL. A WEAK WARM FRONT IS STILL PROGGED TO PUSH ACROSS THE AREA
THROUGHOUT THE DAY TODAY...WHICH WILL BRING THE POTENTIAL FOR FURTHER
DEVELOPMENT OF SHOWERS AND THUNDERSTORMS...PARTICULARLY THIS
AFTERNOON DURING PEAK HEATING. AFTER A LULL IN THE ACTION MONDAY
NIGHT AND TUESDAY MORNING...THE WARM FRONT IS EXPECTED TO BECOME
ACTIVE ONCE AGAIN...WITH ISOLATED SHOWERS AND STORMS POSSIBLE ACROSS
THE NORTHERN AND NORTHEASTERN THIRD OF THE FORECAST AREA. RIGHT NOW
THE LIMITING FACTORS APPEAR TO BE THE AMOUNT LOW LEVEL MOISTURE
AVAILABLE AND THE DIFFUSE NATURE OF THE WARM FRONT. TEMPERATURES
TODAY AND TOMORROW WILL TOP OUT AT WELL ABOVE NORMAL VALUES...AS
SOUTHERLY FLOW BECOMES ESTABLISHED. TODAYS HIGHS ARE EXPECTED TO MAX
OUT IN THE LOW TO MID 80S...WITH MID 80S EXPECTED AREA WIDE ON
TUESDAY...AS CLOUD COVER THINS OUT QUITE A BIT.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 408 AM EDT MON MAY 27 2013
UPPER LEVEL RIDGING OVER THE SOUTHEAST CONUS AND LOW LEVEL SOUTHERLY
FLOW WILL BRING A PERIOD OF WARM SUMMER-LIKE WEATHER UNTIL THE
WEEKEND. WHILE THERE IS A REMOTE POSSIBILITY OF DIURNALLY DRIVEN
THUNDERSTORMS POPPING UP...THE POP IN ANY GIVEN 12 HOUR PERIOD IS
WELL BELOW 20 PERCENT UNTIL THE WEEKEND.
AN UPPER LEVEL TROUGH AND ITS ASSOCIATED SURFACE COLD FRONT ARE
EXPECTED TO APPROACH DURING THE WEEKEND. THIS WILL BRING A
POSSIBILITY OF SHOWERS AND THUNDERSTORMS SATURDAY NIGHT AND SUNDAY.
WITH THE INCREASE IN CLOUDS AND POSSIBLE PRECIP ON SUNDAY...TEMPS
WILL ALSO COOL OFF A BIT. THE MOST LIKELY TIME FOR COLD FRONTAL
PASSAGE IS SUNDAY NIGHT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 230 PM EDT MON MAY 27 2013
VFR CONDITIONS SHOULD PREVAIL THROUGHOUT THE TAF PERIOD AT ALL THREE
AIRPORTS. ISOLATED SHOWERS AND STORMS COULD AFFECT JKL THROUGH AROUND
0Z. OTHERWISE...CU NEAR 5 TO 6KFT SHOULD CONTINUE TO DEVELOP OVER THE
NEXT TWO TO THREE HOURS...BEFORE DIMINISHING. WITH THE WARM FRONT NOW
MOVING INTO WV...WINDS WILL AVERAGE OUT OF THE SOUTH SOUTHWEST TO
SOUTHWEST. WINDS WILL SLACKEN OVERNIGHT...BEFORE PICKING UP AT NEAR
10KT...ESPECIALLY LOZ AND SME AFTER 15Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...AR
LONG TERM...HAL
AVIATION...JP
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1255 PM EDT MON MAY 27 2013
...Updated Aviation Discussion...
.Forecast Update...
Issued at 1220 PM EDT Mon May 27 2013
Quick update for temperatures today. The consensus of the short-term
models indicates we should get up closer to the mid 80s today for
most of the region, and almost full sunshine this morning is helping
temperatures to run up. KSDF now is in the low 80s. We should see
some cumulus pop up under these warm conditions to help slow down
the increase. As for afternoon storm chances, we have a band of
convergence tailing from the MCV over northeast IL now, and this
band has some enhanced cu over southwest IN. Timing this band has it
over the I-65 corridor by 18Z, and our northeast forecast area by
20Z. Think the best focus for storms will be in this band, with
subsidence behind it. Will keep isolated-widely scattered coverage
in grids for now. Upstream band over northern Missouri is behaving
close to HRRR and RAP forecasts as well as 4 km NAM. All of those
models show it dissipating towards sunset, before getting into our
region. Will keep watch in case it starts accelerating toward our
northwest area.
Issued at 950 AM EDT Mon May 27 2013
Still looking like isolated to scattered convection will develop
later this afternoon. GOES Sounder data indicates the airmass has
dried out some now, but more moisture will advect into the region
this afternoon. In addition we have a weak warm front in the
vicinity, which is difficult to pick up in the wind field but a
little more apparent in the temp/dewpoint fields, with 60/low 50s
over our northeast and 70/60 over the southwest. We also have
residual boundaries from activity to our north overnight, along with
an atmosphere that should become less capped over the north later
this afternoon, as per RAP and NAM soundings. Given the combination
of these factors, have shifted the isolated storm line a little
south, but kept south central Kentucky dry for today. Some of the
high-res models are bringing a more organized line of storms in from
the west, from the system now over northern Missouri, and will have
to watch trends upstream to see if an update is necessary later.
Most of these models have any line that does move east weakening
quickly with sunset, but still have kept in isolated storm into the
evening to account for this possibility.
Issued at 630 AM EDT Mon May 27 2013
Current forecast remains on track at this time. Did adjust PoPs
downward across the region for the next several hours as convection
to our north continues to pull away from our area with little in the
way of downstream development. We do anticipate isolated to
scattered development later this afternoon. Temperatures are
nearing their overnight minimums with readings in the mid to upper
50s and will start to recover in the next hour once the sun comes up.
&&
.Short Term (Now - Tuesday)...
Issued at 325 AM EDT Mon May 27 2013
IR satellite and surface observations reveal clear mostly clear to
partly cloudy skies across the region this morning. Main batch of
cloudiness is across southern Indiana associated with convective
debris. Temperatures ranged from the middle 50s in our eastern
counties with lower 60s across our western sections. Some isolated
convection continues to move across far northern KY this morning.
This activity should continue to head on off to the east and may
clip our northern Bluegrass counties. For this reason, will hold on
to isolated shower/storm chances for the remainder of the morning
hours. Temperatures should continue to cool over the next few hours
with most locations dropping into the mid-upper 50s with readings
around 60 in the urban areas.
For Today, we`re likely to see partly cloudy skies across the
region. Weak frontal boundary that has been across the northern
sections will slowly advance northward during the day. Latest model
data suggests a weak upper level wave will approach the region from
the west during the afternoon hours. Overall moisture profile is
not all that great across the region. However, with slightly more
insolation today, we should have a little more instability to work
with this afternoon. Current indications are that the best chances
of showers and storms would generally be across southern Indiana and
portions of north-central Kentucky this afternoon...generally north
of the Western Ky and Bluegrass Parkways with drier conditions in
southern Kentucky. We should see warmer temperatures today with
highs in the lower 80s in southern Indiana and northern Kentucky
with mainly lower-middle 80s across southern Kentucky.
Dry conditions look likely as we head into the evening hours tonight
as any convection will probably slacken off with the loss of heating
and increasing stability within the PBL. Lows will cool into the
lower to middle 60s. High pressure and associated upper level
ridging will build into the region for Tuesday resulting in sunny
and warmer conditions with highs in the 81 to 86 degree range.
.Long Term (Tuesday Night- Sunday)...
Issued at 300 AM EDT Mon May 27 2013
Ridging aloft and high pressure at the surface will remain in
control for the latter half of the work week. Winds will be out of
the south with partly cloudy skies. Dry weather is expected through
this time frame. Temperatures will be on the warm side with highs
each day in the mid to upper 80s. Lows will range from the mid to
upper 60s.
Going into the weekend a low pressure system will track across the
Great Lakes region. A cold front associated with this system will
slowly approach the area Saturday and looks to finally push
through Sunday afternoon/night. Showers and thunderstorms will
accompany this front. For Saturday the best chance for showers and
thunderstorms will be along and north of the Ohio River.
Precipitation will slowly spread southeast overnight Saturday with a
better chance for precip areawide on Sunday. Temps Saturday look to
still top out in the mid 80s with highs in the lower 80s on Sunday.
Lows will be in the 60s.
&&
.Aviation (18Z TAF Issuance)...
Issued at 1255 PM EDT Mon May 27 2013
Have a band of increasing cloud cover moving towards KSDF this hour,
but should pass through before being enough to support storms. Bases
are well into the VFR range, so no concerns here. Upstream storm
system still behaving well with high-res models, and they insist it
will weaken with loss of heating, so will keep storm chances out of
the TAFs late this aftn/evening. Winds should gust from the
southwest the rest of the aftn with a tightening pressure gradient
over us. Gusts of 15-20 knots are likely this afternoon, and again
starting late morning Tuesday.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Updates..........MJ/RJS
Short Term.......MJ
Long Term........EER
Aviation.........RJS
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1224 PM EDT MON MAY 27 2013
.Forecast Update...
Issued at 1220 PM EDT Mon May 27 2013
Quick update for temperatures today. The consensus of the short-term
models indicates we should get up closer to the mid 80s today for
most of the region, and almost full sunshine this morning is helping
temperatures to run up. KSDF now is in the low 80s. We should see
some cumulus pop up under these warm conditions to help slow down
the increase. As for afternoon storm chances, we have a band of
convergence tailing from the MCV over northeast IL now, and this
band has some enhanced cu over southwest IN. Timing this band has it
over the I-65 corridor by 18Z, and our northeast forecast area by
20Z. Think the best focus for storms will be in this band, with
subsidence behind it. Will keep isolated-widely scattered coverage
in grids for now. Upstream band over northern Missouri is behaving
close to HRRR and RAP forecasts as well as 4 km NAM. All of those
models show it dissipating towards sunset, before getting into our
region. Will keep watch in case it starts accelerating toward our
northwest area.
Issued at 950 AM EDT Mon May 27 2013
Still looking like isolated to scattered convection will develop
later this afternoon. GOES Sounder data indicates the airmass has
dried out some now, but more moisture will advect into the region
this afternoon. In addition we have a weak warm front in the
vicinity, which is difficult to pick up in the wind field but a
little more apparent in the temp/dewpoint fields, with 60/low 50s
over our northeast and 70/60 over the southwest. We also have
residual boundaries from activity to our north overnight, along with
an atmosphere that should become less capped over the north later
this afternoon, as per RAP and NAM soundings. Given the combination
of these factors, have shifted the isolated storm line a little
south, but kept south central Kentucky dry for today. Some of the
high-res models are bringing a more organized line of storms in from
the west, from the system now over northern Missouri, and will have
to watch trends upstream to see if an update is necessary later.
Most of these models have any line that does move east weakening
quickly with sunset, but still have kept in isolated storm into the
evening to account for this possibility.
Issued at 630 AM EDT Mon May 27 2013
Current forecast remains on track at this time. Did adjust PoPs
downward across the region for the next several hours as convection
to our north continues to pull away from our area with little in the
way of downstream development. We do anticipate isolated to
scattered development later this afternoon. Temperatures are
nearing their overnight minimums with readings in the mid to upper
50s and will start to recover in the next hour once the sun comes up.
&&
.Short Term (Now - Tuesday)...
Issued at 325 AM EDT Mon May 27 2013
IR satellite and surface observations reveal clear mostly clear to
partly cloudy skies across the region this morning. Main batch of
cloudiness is across southern Indiana associated with convective
debris. Temperatures ranged from the middle 50s in our eastern
counties with lower 60s across our western sections. Some isolated
convection continues to move across far northern KY this morning.
This activity should continue to head on off to the east and may
clip our northern Bluegrass counties. For this reason, will hold on
to isolated shower/storm chances for the remainder of the morning
hours. Temperatures should continue to cool over the next few hours
with most locations dropping into the mid-upper 50s with readings
around 60 in the urban areas.
For Today, we`re likely to see partly cloudy skies across the
region. Weak frontal boundary that has been across the northern
sections will slowly advance northward during the day. Latest model
data suggests a weak upper level wave will approach the region from
the west during the afternoon hours. Overall moisture profile is
not all that great across the region. However, with slightly more
insolation today, we should have a little more instability to work
with this afternoon. Current indications are that the best chances
of showers and storms would generally be across southern Indiana and
portions of north-central Kentucky this afternoon...generally north
of the Western Ky and Bluegrass Parkways with drier conditions in
southern Kentucky. We should see warmer temperatures today with
highs in the lower 80s in southern Indiana and northern Kentucky
with mainly lower-middle 80s across southern Kentucky.
Dry conditions look likely as we head into the evening hours tonight
as any convection will probably slacken off with the loss of heating
and increasing stability within the PBL. Lows will cool into the
lower to middle 60s. High pressure and associated upper level
ridging will build into the region for Tuesday resulting in sunny
and warmer conditions with highs in the 81 to 86 degree range.
.Long Term (Tuesday Night- Sunday)...
Issued at 300 AM EDT Mon May 27 2013
Ridging aloft and high pressure at the surface will remain in
control for the latter half of the work week. Winds will be out of
the south with partly cloudy skies. Dry weather is expected through
this time frame. Temperatures will be on the warm side with highs
each day in the mid to upper 80s. Lows will range from the mid to
upper 60s.
Going into the weekend a low pressure system will track across the
Great Lakes region. A cold front associated with this system will
slowly approach the area Saturday and looks to finally push
through Sunday afternoon/night. Showers and thunderstorms will
accompany this front. For Saturday the best chance for showers and
thunderstorms will be along and north of the Ohio River.
Precipitation will slowly spread southeast overnight Saturday with a
better chance for precip areawide on Sunday. Temps Saturday look to
still top out in the mid 80s with highs in the lower 80s on Sunday.
Lows will be in the 60s.
&&
.Aviation (12Z TAF Issuance)...
Issued at 630 AM EDT Mon May 27 2013
VFR conditions are expected to continue at the TAF sites through the
upcoming forecast period. Convective debris, in the form of
mid-high level cloud cover continues to overspread the northern
sections of the forecast area this morning. This will mainly affect
KSDF and KLEX but will have no impact on aviation. Surface winds
will start of light and variable and then pick up out of the south
by mid-morning and into the afternoon hours. Upper level
disturbance is still on track to pass through the region later this
afternoon which may spark an isolated shower or storm this
afternoon. Coverage is still sparse to include in the upcoming TAF
forecast at this time.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Updates..........MJ/RJS
Short Term.......MJ
Long Term........EER
Aviation.........MJ
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1004 AM EDT MON MAY 27 2013
.UPDATE...
ISSUED AT 1003 AM EDT MON MAY 27 2013
THE NEAR TERM TEMPS...DEWPOINTS AND SKY AS WELL AS POPS WERE ADJUSTED
BASED ON RECENT OBS AS WELL AS SATELLITE AND RADAR TRENDS. TEMPS ARE
WARMING UP RATHER QUICKLY IN THE SOUTHWEST WHERE THE FLOW IS MORE
SOUTHERLY AND THERE ARE FEW IN THE WAY OF CLOUDS BEHIND A NORTHWARD
LIFTING WARM FRONT. THE DIURNAL CLIMO CURVE IN GENERAL IS NOT
CAPTURING THE TEMPERATURE RISE AND OPTED TO GO WITH MORE A MOS
DERIVED TEMP CURVE FOR TODAY. MEANWHILE...A BAND OF CLOUDS IS WORKING
INTO THE SOUTHEASTERN PART OF THE CWA. BEHIND THIS BAND...SKIES
SHOULD BE MOSTLY SUNNY IN ALL AREAS INTO THE EARLY AFTERNOON WHEN CU
MAY BEGIN TO FORM. MODELS...ESPECIALLY THE 6Z NAM APPEARS TO BE TOO
AGGRESSIVE WITH THE INCREASE IN LOW LEVEL MOISTURE AND SFC AND
BOUNDARY LAYER DEWPOINTS WHEN COMPARED TO 12Z RAOB FROM NASHVILLE.
INSTABILITY IN THE 6Z NAM FORECAST SOUNDINGS IS LIKELY OVERDONE AS
DEWPOINTS WILL LIKELY MIX INTO THE LOW TO MID 50S RATHER THAN MID TO
UPPER 50S IN THE 6Z NAM...AND THIS MAY LEAD TO OBSERVED CAPE MUCH AS
1000 J/KG LESS THAN THE 6Z NAM FORECAST SOUNDINGS. THE 11Z HRRR SHOWS
VERY LITTLE CONVECTIVE DEVELOPMENT TODAY WITH CONVECTION GENERALLY
ALONG A CORRIDOR NEAR OR MAINLY NORTH OF THE OH RIVER THEN SOUTHEAST
TOWARD THE CENTRAL APPALACHIANS. THE 11Z HRRR HINTS AT SOME POSSIBLE
DEVELOPMENT NEAR THE WV BORDER AND ITS SCENARIO APPEARS REASONABLE.
FOR THIS UPDATE...CONFINED SLIGHT CHANCE POPS TO THE AFTERNOON INTO
EARLY EVENING AND OVER THE EASTERN THIRD TO HALF OF THE CWA. THE
BOTTOMLINE IS MOST LOCATIONS WILL LIKELY NOT EXPERIENCE ANY
CONVECTION TODAY.
THE 12Z NAM AND 9Z SREF HINT AT SOME CONVECTION THIS EVENING AND
BRING A WEAK SHORTWAVE ACROSS THE AREA. THE 11Z HRRR DOES NOT HAVE
THIS AND CONFIDENCE IN THIS IS NOT HIGH...BUT TRENDS WITH THIS WILL
BE MONITORED AS THE ENTIRE SUITE OF 12Z MODEL RUNS ARRIVE.
UPDATE ISSUED AT 651 AM EDT MON MAY 27 2013
NO MAJOR CHANGES WERE MADE TO THE FORECAST THIS MORNING. RAN THE ESTF
TOOL TO INGEST THE LATEST OBSERVATIONAL DATA AND INTEGRATE IT WITH
THE 4 AM FORECAST DATA. OVERALL THE FORECAST IS ON TRACK SO FAR
TODAY. SCATTERED SHOWERS AND STORMS CONTINUE TO MOVE ACROSS SOUTHERN
INDIANA AND OHIO...WITH A FEW OF THESE OCCASIONALLY STRAYING SOUTH
INTO THE NORTHERN FRINGES OF THE FORECAST AREA. THIS TREND IS
EXPECTED TO CONTINUE FOR THE NEXT SEVERAL HOURS. ACTIVITY IS EXPECTED
TO INCREASE A BIT DURING THE PEAK HEATING OF THE DAY...AS A ILL
DEFINED WARM FRONT MOVES IN FROM THE SOUTHWEST. NO UPDATE IS PLANNED
AT THIS TIME.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 301 AM EDT MON MAY 27 2013
MODELS WERE IN PRETTY GOOD AGREEMENT FOR THE SHORT TERM PORTION OF
THE FORECAST. THE CONSENSUS VIEW IS FOR ISOLATED SHOWERS AND STORMS
TO PUSH JUST TO THE SOUTH OF THE OHIO RIVER TODAY AND AGAIN LATE IN
THE DAY ON TUESDAY. THE LATEST RADAR IMAGERY SHOWED SCATTERED SHOWERS
AND STORMS MOVING ACROSS SOUTHERN INDIANA...NORTH CENTRAL
KENTUCKY...AND SOUTHWESTERN OHIO. A FEW OF THESE MIGHT MAKE INTO THE
NORTHERN MOST AREAS OF THE FORECAST BY EARLY THIS MORNING.
THEREFORE...SLIGHT CHANCE POPS WERE LEFT IN PLACE TO ACCOUNT FOR THIS
POTENTIAL. A WEAK WARM FRONT IS STILL PROGGED TO PUSH ACROSS THE AREA
THROUGHOUT THE DAY TODAY...WHICH WILL BRING THE POTENTIAL FOR FURTHER
DEVELOPMENT OF SHOWERS AND THUNDERSTORMS...PARTICULARLY THIS
AFTERNOON DURING PEAK HEATING. AFTER A LULL IN THE ACTION MONDAY
NIGHT AND TUESDAY MORNING...THE WARM FRONT IS EXPECTED TO BECOME
ACTIVE ONCE AGAIN...WITH ISOLATED SHOWERS AND STORMS POSSIBLE ACROSS
THE NORTHERN AND NORTHEASTERN THIRD OF THE FORECAST AREA. RIGHT NOW
THE LIMITING FACTORS APPEAR TO BE THE AMOUNT LOW LEVEL MOISTURE
AVAILABLE AND THE DIFFUSE NATURE OF THE WARM FRONT. TEMPERATURES
TODAY AND TOMORROW WILL TOP OUT AT WELL ABOVE NORMAL VALUES...AS
SOUTHERLY FLOW BECOMES ESTABLISHED. TODAYS HIGHS ARE EXPECTED TO MAX
OUT IN THE LOW TO MID 80S...WITH MID 80S EXPECTED AREA WIDE ON
TUESDAY...AS CLOUD COVER THINS OUT QUITE A BIT.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 408 AM EDT MON MAY 27 2013
UPPER LEVEL RIDGING OVER THE SOUTHEAST CONUS AND LOW LEVEL SOUTHERLY
FLOW WILL BRING A PERIOD OF WARM SUMMER-LIKE WEATHER UNTIL THE
WEEKEND. WHILE THERE IS A REMOTE POSSIBILITY OF DIURNALLY DRIVEN
THUNDERSTORMS POPPING UP...THE POP IN ANY GIVEN 12 HOUR PERIOD IS
WELL BELOW 20 PERCENT UNTIL THE WEEKEND.
AN UPPER LEVEL TROUGH AND ITS ASSOCIATED SURFACE COLD FRONT ARE
EXPECTED TO APPROACH DURING THE WEEKEND. THIS WILL BRING A
POSSIBILITY OF SHOWERS AND THUNDERSTORMS SATURDAY NIGHT AND SUNDAY.
WITH THE INCREASE IN CLOUDS AND POSSIBLE PRECIP ON SUNDAY...TEMPS
WILL ALSO COOL OFF A BIT. THE MOST LIKELY TIME FOR COLD FRONTAL
PASSAGE IS SUNDAY NIGHT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 651 AM EDT MON MAY 27 2013
VFR CONDITIONS WILL PREVAIL THROUGHOUT THE TAF PERIOD AT ALL THREE
AIRPORTS. ISOLATED SHOWERS AND STORMS ARE STILL ON TAP FROM LATE THIS
MORNING THROUGH LATE THIS AFTERNOON. MOST OF THE ACTIVITY WILL OCCUR
EAST OF THE I75 CORRIDOR AND NORTH THE HAL ROGERS PARKWAY AND HIGHWAY
80 CORRIDOR. SCATTERED MIDDLE AND BROKEN HIGH LEVEL CLOUD COVER WILL
STREAM ACROSS THE AREA THROUGHOUT THE DAY...AHEAD OF AN APPROACHING
WARM FRONT. WINDS WILL BE OUT OF THE SOUTH AND WILL INCREASE TO 5 TO
10 MPH FOR MOST LOCATIONS BY THIS AFTERNOON.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...AR
LONG TERM...HAL
AVIATION...AR
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
952 AM EDT MON MAY 27 2013
.Forecast Update...
Issued at 950 AM EDT Mon May 27 2013
Still looking like isolated to scattered convection will develop
later this afternoon. GOES Sounder data indicates the airmass has
dried out some now, but more moisture will advect into the region
this afternoon. In addition we have a weak warm front in the
vicinity, which is difficult to pick up in the wind field but a
little more apparent in the temp/dewpoint fields, with 60/low 50s
over our northeast and 70/60 over the southwest. We also have
residual boundaries from activity to our north overnight, along with
an atmosphere that should become less capped over the north later
this afternoon, as per RAP and NAM soundings. Given the combination
of these factors, have shifted the isolated storm line a little
south, but kept south central Kentucky dry for today. Some of the
high-res models are bringing a more organized line of storms in from
the west, from the system now over northern Missouri, and will have
to watch trends upstream to see if an update is necessary later.
Most of these models have any line that does move east weakening
quickly with sunset, but still have kept in isolated storm into the
evening to account for this possibility.
Issued at 630 AM EDT Mon May 27 2013
Current forecast remains on track at this time. Did adjust PoPs
downward across the region for the next several hours as convection
to our north continues to pull away from our area with little in the
way of downstream development. We do anticipate isolated to
scattered development later this afternoon. Temperatures are
nearing their overnight minimums with readings in the mid to upper
50s and will start to recover in the next hour once the sun comes up.
&&
.Short Term (Now - Tuesday)...
Issued at 325 AM EDT Mon May 27 2013
IR satellite and surface observations reveal clear mostly clear to
partly cloudy skies across the region this morning. Main batch of
cloudiness is across southern Indiana associated with convective
debris. Temperatures ranged from the middle 50s in our eastern
counties with lower 60s across our western sections. Some isolated
convection continues to move across far northern KY this morning.
This activity should continue to head on off to the east and may
clip our northern Bluegrass counties. For this reason, will hold on
to isolated shower/storm chances for the remainder of the morning
hours. Temperatures should continue to cool over the next few hours
with most locations dropping into the mid-upper 50s with readings
around 60 in the urban areas.
For Today, we`re likely to see partly cloudy skies across the
region. Weak frontal boundary that has been across the northern
sections will slowly advance northward during the day. Latest model
data suggests a weak upper level wave will approach the region from
the west during the afternoon hours. Overall moisture profile is
not all that great across the region. However, with slightly more
insolation today, we should have a little more instability to work
with this afternoon. Current indications are that the best chances
of showers and storms would generally be across southern Indiana and
portions of north-central Kentucky this afternoon...generally north
of the Western Ky and Bluegrass Parkways with drier conditions in
southern Kentucky. We should see warmer temperatures today with
highs in the lower 80s in southern Indiana and northern Kentucky
with mainly lower-middle 80s across southern Kentucky.
Dry conditions look likely as we head into the evening hours tonight
as any convection will probably slacken off with the loss of heating
and increasing stability within the PBL. Lows will cool into the
lower to middle 60s. High pressure and associated upper level
ridging will build into the region for Tuesday resulting in sunny
and warmer conditions with highs in the 81 to 86 degree range.
.Long Term (Tuesday Night- Sunday)...
Issued at 300 AM EDT Mon May 27 2013
Ridging aloft and high pressure at the surface will remain in
control for the latter half of the work week. Winds will be out of
the south with partly cloudy skies. Dry weather is expected through
this time frame. Temperatures will be on the warm side with highs
each day in the mid to upper 80s. Lows will range from the mid to
upper 60s.
Going into the weekend a low pressure system will track across the
Great Lakes region. A cold front associated with this system will
slowly approach the area Saturday and looks to finally push
through Sunday afternoon/night. Showers and thunderstorms will
accompany this front. For Saturday the best chance for showers and
thunderstorms will be along and north of the Ohio River.
Precipitation will slowly spread southeast overnight Saturday with a
better chance for precip areawide on Sunday. Temps Saturday look to
still top out in the mid 80s with highs in the lower 80s on Sunday.
Lows will be in the 60s.
&&
.Aviation (12Z TAF Issuance)...
Issued at 630 AM EDT Mon May 27 2013
VFR conditions are expected to continue at the TAF sites through the
upcoming forecast period. Convective debris, in the form of
mid-high level cloud cover continues to overspread the northern
sections of the forecast area this morning. This will mainly affect
KSDF and KLEX but will have no impact on aviation. Surface winds
will start of light and variable and then pick up out of the south
by mid-morning and into the afternoon hours. Upper level
disturbance is still on track to pass through the region later this
afternoon which may spark an isolated shower or storm this
afternoon. Coverage is still sparse to include in the upcoming TAF
forecast at this time.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Updates..........MJ/RJS
Short Term.......MJ
Long Term........EER
Aviation.........MJ
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
930 PM EDT TUE MAY 28 2013
.SYNOPSIS...
A LARGE HIGH PRESSURE RIDGE WILL BUILD INTO THE REGION FROM THE
SOUTHERN ATLANTIC COAST THROUGH THE REMAINDER OF THE WEEK.
PRECIPITATION CHANCES WILL DECREASE...THOUGH ISOLATED ACTIVITY
WILL BE POSSIBLE WITH THE MOIST AIRMASS IN PLACE. THIS AREA OF
HIGH PRESSURE WILL ALSO DRAW UP TEMPERATURES WELL ABOVE AVERAGE
OVER THE NEXT FEW DAYS.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
AT 01Z...REGIONAL 88D MOSAIC SHOWS CLUSTER OF STRONG-TO-SEVERE STORMS
OVER THE BAY MOVING TOWARDS DELMARVA. A FEW POPCORN STORMS AROUND
THE DC METRO AREA TO FINISH OFF ANY LINGERING INSTABILITY.
GOES SATL IR IMGRY SHOWS CLEARING TO THE WEST. THIS COUPLED WITH
CALM WINDS OVERNIGHT WILL PRODUCE PATCHES OF FOG ESP IN THOSE
AREAS THAT EXPERIENCED THE SHRA/TSRA THIS EVENING. NIGHTTIME LOWS
WILL RANGE FROM THE UPPER 60S IN DC AND BALT DOWNTOWN AREAS TO THE
UPPER 50S IN THE POTOMAC HIGHLANDS.
INSTABILITY ON WED BUILDS IN QUICKLY LATE MORNING AS EVIDENCED BY
NAM AND RUC CAPES AROUND 1000 J/KG BY NOON. NOT AS MUCH MODEL UVV
AS TODAY WITH LACK OF UPPER FORCING FROM VORT MAX SO NOT EXPECTING
WIDESPREAD SEVERE ON WED AFTERNOON BUT CERTAINLY SCT SHRA/TSTMS
FROM NOON UNTIL SUNSET.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH 6 PM WEDNESDAY/...
ALTHOUGH THE BERMUDA HIGH WILL BE WORKING HIGHER PRESSURES INTO
THE AREA TOMORROW AND BRINGING IN SUBSIDENCE...A WEAKER SHORTWAVE
FROM TODAY WILL SWING THRU THE REGION - PASSING OVER THE HUMID
AIRMASS. THE NAM AND ITS LOCAL DERIVATIVE GUIDANCE...ALONG W/
THE SREF HAVE A PERIOD OF ISOLATED/SCATTERED TSTM DEVELOPMENT WED
AFTN ORIENTED ALONG THE UPPER WAVE...MAINLY ALONG AND E OF THE
BLUE RIDGE. PLACED IN LOW CHANCE POPS AND MAINTAINED THE MUCH
ABOVE AVG TEMPS FOR TMRW AFTN...W/ MANY AREAS APPROACHING 90 BY
MID AFTN.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
UPPER-LEVEL HIGH PRESSURE WILL BUILD OVER THE REGION WHILE BERMUDA
HIGH SETS UP OVER THE ATLANTIC. SUBSIDENCE FROM THE UPPER-LEVEL HIGH
ALONG WITH A SOUTHWEST FLOW AROUND THE BERMUDA HIGH WILL ALLOW FOR
HOT AND HUMID CONDITIONS. MAX TEMPS WEDNESDAY WILL REACH THE UPPER
80S AND LOWER 90S ACROSS MOST LOCATIONS.
WARM AND HUMID CONDITIONS WILL CONTINUE WEDNESDAY NIGHT. MIN TEMPS
WILL RANGE FROM THE 60S ACROSS MOST LOCATIONS TO THE LOWER AND
MIDDLE 70S IN DOWNTOWN WASHINGTON/BALTIMORE.
UPPER-LEVEL HIGH PRESSURE REMAIN OVER THE REGION THURSDAY THROUGH
SATURDAY WHILE BERMUDA HIGH REMAINS OVER THE ATLANTIC. HOT AND HUMID
CONDITIONS ARE EXPECTED DURING THIS TIME...WHICH WILL LEAD TO THIS
SEASONS FIRST HEAT WAVE. MAX TEMPS WILL REACH THE 90S ACROSS MANY
LOCATIONS EACH DAY UNDER PLENTY OF SUNSHINE. TERRAIN CIRCULATION
COULD LEAD TO AN ISOLATED T-STORM DURING THE AFTERNOON/EVENING
HOURS...BUT THE CAPPING INVERSION SHOULD REMAIN STRONG ENOUGH TO
KEEP MOST AREAS DRY. THEREFORE...T-STORMS ARE NOT IN THE FORECAST AT
THIS TIME.
THE RIDGE WILL WEAKEN SUNDAY AND MONDAY ALLOWING FOR A COLD FRONT TO
MOVE INTO THE AREA...BRINGING A BETTER CHANCE FOR SHOWERS AND
THUNDERSTORMS.
&&
.AVIATION /01Z WEDNESDAY THROUGH SUNDAY/...
ALTHO M CLDY VFR CONDS TDA/TNGT. ISOLD TSTMS PSBL THIS AFT/EVE.
HIGH PRESSURE WILL REMAIN OVER THE TERMINALS WEDNESDAY THROUGH
SATURDAY...CAUSING SOUTHWESTERLY WINDS. WIND GUSTS AROUND 15 KNOTS
ARE EXPECTED DURING THE AFTERNOON AND EVENING HOURS EACH DAY. VFR
CONDITIONS WILL DOMINATE...BUT BRIEF PERIODS OF SUBVFR VSBYS ARE
POSSIBLE DURING THE EARLY MORNING HOURS EACH DAY. A COLD FRONT WILL
APPROACH THE TERMINALS SUNDAY AND MONDAY...BRINGING A BETTER CHANCE
FOR SHOWERS AND THUNDERSTORMS.
&&
.MARINE...
WINDS ACROSS THE BAY/TP HAVE REMAINED IN THE 5-10KT RANGE ALL-DAY
AND WILL CONTINUE TO DO SO THROUGHOUT THE EVE/OVERNIGHT HRS. THE
EXCEPTION WILL BE THE LOWER ZONES OF THE MD BAY...WHICH HAVE A
STEADY 10-15KT BREEZE OUT OF THE SSW...WHICH WILL ALSO CONTINUE
OVERNIGHT. ISOLATED SHOWERS/TSTMS WILL DEVELOP OVER THE NEXT
SEVERAL HRS...MOVING E TOWARD THE BAY/TP CARRYING ISOLATED
DOWNDRAFTS THAT COULD WARRANT PERIODS OF SMW/MWS`S.
MUCH THE SAME STORY FOR WED...THOUGH LOWER CHANCES FOR TSTM
ACTIVITY OVER THE WATERS TMRW AFTN/EVE.
BERMUDA HIGH WILL SET UP OVER THE ATLANTIC WEDNESDAY THROUGH
SATURDAY. SOUTHERLY WINDS ARE EXPECTED. WIND GUSTS WILL COME CLOSE
TO SCA CRITERIA...BUT FORECASTED GUSTS ARE CAPPED AROUND 15 KNOTS
DUE TO THE RELATIVELY COOLER WATERS.
A COLD FRONT WILL APPROACH THE WATERS SUNDAY AND MONDAY...BRINGING A
BETTER CHANCE FOR SHOWERS AND THUNDERSTORMS.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
912 PM EDT TUE MAY 28 2013
.SYNOPSIS...
A WARM FRONT WILL CONTINUE PUSH NORTH OF THE REGION THIS EVENING...BRINGING
A CHANCE FOR SHOWERS AND THUNDERSTORMS TO PORTIONS OF THE AREA. HIGH
PRESSURE BECOMES ANCHORED OFF THE MID ATLANTIC COAST LATER TONIGHT
THROUGH THE NEXT SEVERAL DAYS. SUMMERLIKE CONDITIONS AND GENERALLY
DRY CONDITIONS WILL PREVAIL FROM WEDNESDAY INTO THE UPCOMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
THE LATEST RADAR AND SATELLITE DEPICT A LINE OF TSTMS CROSSING THE
BAY AND APPROACHING THE LOWER MD EASTERN SHORE. THIS LINE HAS THE
POTENTIAL TO INITIALLY BE STRONG AS WEAK SHORTWAVE ENERGY COMBINES
WITH MODEST INSTABILITY. HOWEVER...THE LATEST HRRR (23Z) AND SPC
MESOANALYSIS SUGGEST INSTABILITY DECLINES W-E ACROSS THE EASTERN
SHORE HENCE TSTMS ARE EXPECTED TO WEAKEN AS THEY MOVE E. AN
ISOLATED TS IS POSSIBLE ACROSS THE NORTHERN NECK AND VA EASTERN
SHORE THROUGH THE REMAINDER OF THE EVENING...BUT MOST AREAS
ELSEWHERE WILL REMAIN DRY. SKIES CLEAR OUT FROM SW TO NE AFTER
MIDNIGHT. MILD WITH LOWS MAINLY FROM THE LWR TO MID 60S.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
SUMMERLIKE PATTERN LOOKS TO DEVELOP. MODELS IN GOOD AGREEMENT
THAT THE 500 MB RIDGE ALOFT WILL SLOWLY BUILD ON WED AND BECOME
CENTERED ACRS SE VA AND EASTERN NC THU/FRI WITH HEIGHTS AVERAGING
588-590 DM. SFC HIGH PRESSURE WILL BE NEARLY STATIONARY WELL OFF
THE MID ATLC/SE COAST. SUMMER- LIKE CONDITIONS WILL DOMINATE WITH
HIGHS GENLY RANGING FROM THE MID 80S NEAR THE COAST TO THE UPPER
80S TO LOWER 90S INLAND (LOCALLY IN THE UPPER 70S AT THE BEACHES
OF THE EASTERN SHORE WHERE FLOW BACKS TO SSE DURING THE AFTN).
LACK OF ANY REAL TRIGGER WITH THE WARM POOL ALOFT WILL LEAD TO
WEAK LAPSE RATES ALOFT AND LITTLE CHC FOR ANY PCPN. A VERY
ISOLATED LATE AFTN/EVENING TSTM CAN`T BE RULED OUT WITH THE STRONG
SFC HEATING ...BUT COVERAGE IS EXPECTED TO BE 14% OR LESS. THE SKY
WILL AVERAGE OUT PARTLY/MOSTLY SUNNY. AIRMASS WILL NOT BE THAT
HUMID...AS OCEAN TEMPS ARE STILL QUITE COOL AND WITH AFTN
MIXING...EXPECT DEW PTS TO DROP TO THE LWR 60S DURING THE HEAT OF
THE AFTN (MID-UPR 60S IN THE MORNING HRS). SO WHILE IT WILL BE A
MARGINALLY HOT PERIOD...PEAK HEAT INDICES WILL GENLY BE ABOUT THE
SAME AS THE ACTUAL AIR TEMPERATURES. LOWS TEMPERATURES WILL
AVERAGE IN THE MID 60S...WITH UPPER 60S MORE COMMON IN THE URBAN
CENTERS.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
ABOVE NORMAL TEMPS TO CONTINUE THROUGH THE WEEKEND BEFORE A COLD
FRONT CROSSES THE REGION MONDAY INTO TUESDAY.
MUCH BETTER AGREEMENT AMONG OPERATIONAL GUIDANCE IN THE EXTENDED WRT
CNTRL CONUS TROUGH OPENING UP AND PROGRESSING EWD. MODELS CONTINUE
TO STRUGGLE WITH SEVERAL PIECES OF ENERGY DIVING DOWN THE BACKSIDE
OF THE UPPER TROUGH OVER THE PLAINS. MEAN FRONTAL POSITION SAT
MORNING EXPECTED TO BE IN THE VICINITY OF THE GREAT
LAKES...STRETCHING SWWD INTO SRN NM. WAVY UPPER LEVEL PATTERN
EXPECTED TO PRODUCE SEVERAL WAVES ALONG THE SFC FRONT AS IT SLOWLY
PROGRESSES EWD. WHILE LATEST GFS AND EURE DERIVE UPPER LEVEL ENERGY
FROM DIFFERENT SOURCES...MEDIUM RANGE MODELS IN GOOD AGREEMENT WITH
EJECTING A SHORTWAVE EWD FROM THE LOWER MO RIVER VALLEY SUN
AFTERNOON. SHORTWAVE THEN FORECAST TO PHASE WITH UPPER TROUGH AS IT
TRAVERSES THE ERN STATES...REACHING THE LOCAL AREA MONDAY AFTERNOON.
MEANWHILE...UPPER/SFC HIGH PRESSURE WILL BE PUSHED FARTHER OFFSHORE
AS THE TROUGH APPROACHES. THE RESULT WILL BE DEEP SWLY FLOW AND
MOISTURE ADVECTION OVER THE MID ATLANTIC. DEEP MOISTURE EXPECTED AS
PRECIP WATER VALUES APPROACH 2 INCHES (+2 STD DEV) MON AFTERNOON.
PREVIOUSLY MENTIONED WEAKNESS UNDERCUTTING THE RIDGE EXPECTED TO
REMAIN WELL OFFSHORE. MODELS IN FAIR AGREEMENT (GFS ~ 6 HOURS
SLOWER) WITH TIMING OF THE FRONT MON AFTERNOON THROUGH MON NIGHT.
WHILE ITS STILL DAY 7...POTENTIAL FOR ONE OR MORE FRONTAL WAVES AND
DEEP MOISTURE COULD PRODUCE LOCALLY HEAVY RAINFALL ACROSS THE REGION
(WHICH IS NOT UNCHARACTERISTIC FOR THIS TIME OF YEAR). THETA-E
ADVECTION AND TEMPS IN THE LOW/MID 80S WILL MAINTAIN A MARGINALLY
UNSTABLE AIRMASS FOR THUNDERSTORM ACTIVITY. EXTENDED RANGE MODELS
SUGGEST BLOCKING OVER THE NRN ATLANTIC MAY CAUSE THE TROUGH TO HANG
UP ALONG THE COAST WITH SHOWERS POSSIBLY CONTINUING INTO TUES.
WARM/UNSTABLE AIRMASS WITH STEEP LOW LEVEL LAPSE RATES WILL PROVIDE
FOR AFTERNOON CU SAT-SUN. HOWEVER...NEAR SEASONABLE PRECIP
WATERS...COOL OCEAN TEMPS (DEWPOINTS IN THE LOW/MID 60S) AND A LACK
OF UPPER LEVEL SUPPORT (WEAK FLOW) WILL LIMIT AFTERNOON
CONVECTION...EVEN WITH THE PRESENCE OF A WEAK LEE SIDE TROUGH. THUS
HAVE CAPPED AFTERNOON POPS AT 10-14 PCT AND OVERNIGHT POPS AT 10
PCT. DAYTIME TEMPS +1 STD DEV FORECAST THROUGH SUNDAY. SLIGHTLY
COOLER MONDAY (LOW/MID 80S) AND TUESDAY (UPPER 70S/LOW 80S).
&&
.AVIATION /01Z WEDNESDAY THROUGH SUNDAY/...
CHALLENGING FCST NEXT 2-6 HRS AS TO WHERE AND WHEN ANY CONVECTION
DVLPS. RUC SUGGESTS SOME ACTIVITY DVLPNG NEXT 2 HRS ALONG LINE OF
AC CLOUD DECK CRNTLY LCTD FROM OXB-RIC WHILE NAM/SREF WAIT UNTIL
AFTR 22Z FOR ACTIVITY TO DVLP ACROSS MTS THEN MOVE EAST. GIVEN THE
CRNT CNDTNS LEANED TOWARD THE LATE AFTRN/ERLY EVE FOR CONVECTION
TO DVLP THEN MOVE EAST. THIS TO BE MAINLY ACROSS NRN HALF OF FA
(RIC/SBY) BTWN 22-02Z WHILE SRN TAF SITES (ORF/PHF/ECG) STAY DRY.
THUS...WENT AHEAD AND ADDED CB TO THE RIC AND SBY TAFS TOWARD 00Z.
APPEARS THAT SBY HAS THE GREATEST CHC FOR PCPN. SW WNDS AVG 10-20
KTS THRU 22Z.
OTW...XPCT VFR CNDTNS WITH ONLY HIGH LVL CLDNS (AOA 12K FT) TONITE.
SOME LGT BR PSBL LATE TONITE...BUT THAT WUD BE WHERE ANY RAIN OCCURS
SO HELD OFF WITH ANY BR ATTM.
OUTLOOK...BERMUDA HIGH PRESSURE ESTABLISHES ITSELF OFF THE COAST
FOR THE REMAINDER OF THE WEEK. DRY WITH VFR CNDTNS XPCTD.
&&
.MARINE...
WARM FRONT HAS LIFTED OVER THE WATER THIS AFTERNOON WITH S/SW WINDS
AOB 15 KT IN THE BAY AND AOB 20 KT COASTAL WATERS POST FRONTAL.
GRADIENT BETWEEN STRONG LOW PRESSURE OVER THE MIDWEST AND HIGH
PRESSURE OVER THE WRN ATLANTIC WILL RESULT IN INCREASING WINDS ALOFT
OVER THE WATERS. WAA AND A STRONG LOW LEVEL INVERSION WILL INHIBIT
THESE HIGHER VELOCITY WINDS FROM REACHING THE WATER. HOWEVER...WINDS
OVER THE BAY MAY STILL GUST OVER 15 KT AT TIMES THROUGH
TONIGHT...ESPECIALLY WITH SLY CHANNELING. WAVEWATCH GUIDANCE BRINGS
IN 5 FT SEAS 20 NM OUT TONIGHT...BUT LOOKS LIKE IT MAY BE OVERDONE.
NO SCA HEADLINES ANTICIPATED ATTM TONIGHT. THEREAFTER...AN EXTENDED
PERIOD OF HIGH PRESSURE/FAIR WEATHER (SUB SCA CONDITIONS) EXPECTED
THROUGH THE UPCOMING WEEKEND. S/SW WINDS AOB 15 KT. WAVES 1 TO 2 FT
AND SEAS 2 TO 4 FT.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LKB
NEAR TERM...LKB/AJZ
SHORT TERM...LKB
LONG TERM...SAM
AVIATION...MPR
MARINE...SAM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
758 PM EDT TUE MAY 28 2013
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 352 PM EDT TUE MAY 28 2013
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW UPR RDG OVER THE
GREAT LKS DOWNSTREAM OF DEEPENING TROF OVER THE WRN CONUS. THERE ARE
A PAIR OF SHRTWVS IN THE NRN PLAINS/UPR MS RIVER VALLEY LIFTING NEWD
IN THE SW FLOW ALF BTWN THE LARGER SCALE FEATURES. THE FIRST OF
THESE IS MOVING THRU IOWA AND CAUSING A BAND OF SHRA/SOME TS N OF
SFC/H85 WARM FNT IN THE LOWER GREAT LKS. THE BULK OF THESE SHRA ARE
MOVING ENEWD THRU LWR MI AND ON TRACK TO MISS THE CWA...BUT SOME SCT
-SHRA EXTENDING AS FAR W AS MPX ARE SHIFTING NEWD THRU WI AND
CLOSING IN ON THE SCNTRL CWA. THE HEAVIER/MOST WDSPRD SHRA MISSING
THE CWA TO THE SE APPEAR BEST CORRELATED WITH THE SHARPEST H85-5
QVECTOR CNVGC...WHILE THE SHRA IN WI APPEAR TIED TO ISENTROPIC
ASCENT ON THE 300-305K SFCS /H85-7/. OTRW...SKIES ARE CLDY OVER THE
CWA N OF THE WARM FNT WITH AMPLE MSTR IN THE SFC-H7 LYR SHOWN ON THE
12Z MPX/GRB/APX RAOBS. THESE CLDS HAVE GREATLY RESTRICTED THE
DIURNAL RECOVERY OF TEMP. BEHIND THE OTHER SHRTWV OVER NDAKOTA...A
MUCH DRIER AIRMASS IS NOTED SHIFTING EWD THRU THE NRN PLAINS.
FCST CONCERNS IN THE SHORT TERM INVOLVE POPS ASSOCIATED WITH
SHRTWV/WARM FNT TO THE S AND THEN DRYING TRENDS LATER TNGT INTO WED
AS DRY AIRMASS IN THE NRN PLAINS MOVES INTO THE UPR LKS.
TNGT...SINCE DEEPER H85-5 QVECTOR CNVGC IS PROGGED TO DRIFT ENEWD
THRU LWR MI AND INTO SE ONTARIO...EXPECT HEAVIER SHRA TO REMAIN SE
OF UPR MI. HOWEVER...WITH SHRTWV IN IOWA APRCHG THE CWA THRU WI AND
BAND OF ISENTROPIC ASCENT ON THE 300-305K SFCS IMPACTING MAINLY THE
CENTRAL AND ERN ZNS THIS EVNG...EXPECT AT LEAST ISOLD -SHRA TO DRIFT
THRU THIS AREA...MAINLY NEAR THE GREEN BAY/LK MI. LATER TNGT AFT THE
SHRTWV DRIFTS TO THE NE OF UPR MI AND HGTS BEGIN TO RISE UNDER THE
DNVA/VIGOROUS DEEP LYR QVECTOR DVGC IN THE WAKE OF THIS
DISTURBANCE...EXPECT A DRYING TREND ALF AND FOR ANY PCPN TO END W-E.
BUT LO CLDS AND SOME FOG WL BE AROUND WITH LINGERING LLVL MSTR AND
ONLY WEAK HI PRES SHIFTING OVHD. WITH THE LINGERING LO CLDS...TEMPS
SHOULD FALL ONLY A COUPLE OF DEGREES.
WED...UNDER RISING HGTS/DEEP LYR QVECTOR DVGC UNDER SHRTWV RDGING
ALF...EXPECT MID LVL DRYING AS AIRMASS NOW MOVING THRU THE NRN
PLAINS SHIFTS INTO THE UPR LKS. ALTHOUGH LO CLDS/SOME FOG WL LINGER
THRU SUNRISE...DIURNAL HEATING/MIXING SHOULD TEND TO BREAK UP THIS
LO CLD. SHARP SUBSIDENCE INVRN SHOWN ON FCST SDNGS BTWN H75-8 AND
LLVL ACYC FLOW WL TEND TO SQUASH ANY CONVECTION THAT MIGHT TRY TO
FIRE WITH DAYTIME HEATING/MORE HUMID LLVL AIRMASS THAT WL SUPPORT
SFC DEWPTS WELL INTO THE 50S. IN FACT...NAM/ GFS FCST SDNGS SHOW
CONVECTIVE TEMP AOA 90. MIXING TO H8-85 ON THESE FCST SDNGS HINT MAX
TEMPS WL REACH ARND 80 AWAY FM LK MODERATION.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 352 PM EDT TUE MAY 28 2013
WARM AND ACTIVE WEATHER PATTERN EXPECTED TO CONTINUE THROUGH MUCH OF
THE WEEKEND. FOG WILL ALSO BE PROBLEMATIC OVER THE GREAT LAKES AS
WARMER AIR MOVES INTO THE AREA ENHANCING THE MARINE LAYER.
THIS...COUPLED WITH RAIN FALLING INTO THE MARINE LAYER...WILL
INCREASE THE MOISTURE TRAPPED IN THE MARINE LAYER AIDING IN FOG
FORMATION. THE FOG IS EXPECTED TO MIX OUT BY THE LAST HALF OF THE
WEEKEND AS COOLER AIR MOVES IN ALOFT AND DRY AIR SPILLS OUT OF
CANADA INTO THE UPPER GREAT LAKES REGION.
WEDNESDAY NIGHT THROUGH THURSDAY...A WARM FRONT...EXTENDING FROM
SOUTHERN MN EASTWARD INTO CENTRAL WI AND CENTRAL LOWER MI WEDNESDAY
AFTERNOON...WILL LIFT NORTHWARD INTO THE UPPER MICHIGAN BETWEEN 00Z
AND 06Z WEDNESDAY NIGHT AS SHOWN BY OVERLAYING 850MB THETA E ALONG
WITH 850MB WINDS. THIS HAPPENS AROUND THE SAME TIME THAT HEIGHT
FALLS...ASSOCIATED WITH THE SURFACE LOW AND UPPER LEVEL 500MB LOW
OVER THE WEST HALF OF THE UNITED STATES...BEGIN TO SHIFT EASTWARD
INTO THE WESTERN UPPER PENINSULA. MOISTURE TRANSPORT INTO THE
REGION...ALONG WITH CONVERGENCE ALONG THE NOSE OF THE 850MB LLJ
LIFTING NORTHWARD INTO SOUTHEASTERN MN AND WESTERN WI...WILL BE
FAVORABLE FOR SHOWER AND THUNDERSTORM DEVELOPMENT. CAPE VALUES
DURING THIS TIME ARE PROGGED TO BE BETWEEN 500 J/KG AND 1000 J/KG
WITH THE NAM BEING ON THE HIGHER END AND MANY OF THE OTHER MODELS
AROUND 500-600 J/KG. WHILE INSTABILITY VALUES ARE FAVORABLE FOR
THUNDERSTORM DEVELOPMENT...THE CHANCES OF SVR WEATHER AT THIS POINT
ARE LIMITED AS BULK SHEAR VALUES WOULD BE MARGINAL...RANGING FROM 20
TO 25 KTS. FOR A MORE ORGANIZED SVR WEATHER THREAT...BULK SHEAR
VALUES WOULD NEED TO BE CLOSER TO 40-45 KNOTS OR GREATER.
THURSDAY NIGHT THROUGH FRIDAY...THE UPPER LEVEL LOW WILL REMAIN
NEARLY STATIONARY OVER THE NORTHERN PLAINS THROUGH THIS TIME PERIOD.
THE MAIN ISSUE WILL BE A SHORTWAVE PROGGED TO ROTATE AROUND THIS
UPPER LEVEL LOW AS THE SURFACE LOW SHIFTS INTO NORTHERN MN. EXACT
TIMING AND STRENGTH OF THE SHORTWAVE DIFFER FROM MODEL TO MODEL WITH
THE GFS STILL TRYING TO BRING A MUCH MORE AGGRESSIVE SHORTWAVE INTO
THE AREA. CURRENT TRENDS ARE SHOWING THAT THE SHORTWAVE OVER THE
PLAINS STATES THURSDAY NIGHT WILL ROTATE NORTHEASTWARD...REACHING
THE U.P. BY LATE MORNING TO EARLY AFTERNOON FRIDAY. CONFIDENCE IN
INTENSITY AND TIMING OF THE SHORTWAVE IS FAIRLY LOW AS THESE THINGS
ARE HIGHLY DEPENDENT UPON CONVECTIVE DEVELOPMENT.
FRIDAY NIGHT THROUGH SATURDAY NIGHT...THE SURFACE LOW WILL SHIFT
FROM NORTHERN MN FRIDAY NIGHT INTO UPPER MI SATURDAY AND INTO LOWER
MI SATURDAY NIGHT. AT THE SAME TIME THE UPPER LEVEL 500MB TROUGH
WILL SHIFT FROM NORTHERN MN INTO UPPER MI. THE CHANCE FOR SHOWERS
AND THUNDERSTORMS WILL CONTINUE OVER UPPER MI INTO SATURDAY
AFTERNOON...BEFORE THE SURFACE LOW SHIFTS INTO NORTHERN LOWER MI.
ON THE BACK SIDE OF THE SURFACE LOW SATURDAY EVENING...THE CHANCES
FOR THUNDERSTORM ACTIVITY WILL DIMINISH GREATLY...HOWEVER...THE
CHANCE FOR SHOWERS WILL REMAIN IN THE FORECAST AS THE UPPER LEVEL
TROUGH MOVES OVERHEAD.
SUNDAY AND SUNDAY NIGHT...THE 500MB TROUGH OVER THE UPPER PENINSULA
WILL SHIFT SLOWLY EASTWARD THROUGH SUNDAY NIGHT ALLOWING THE CHANCE
OF SHOWERS TO SLOWLY DIMINISH THROUGH SUNDAY EVENING. THE 06Z AND
12Z GFS STILL REMAINS THE OUTLIER AS IT TRIES TO PULL DRY AIR FROM
CANADA INTO THE UPPER PENINSULA TOO QUICKLY...AROUND 18Z...WHILE THE
EC/GEM KEEP THE MOISTURE IN PLACE THROUGH 00Z-06Z. THE NEW 06Z RUN
OF THE GFS TRENDED CLOSER TO THE EC/GEM...THEREFORE WILL HANG ON TO
CLOUD COVER AND CHANCE OF SHOWERS INTO EARLY SUNDAY EVENING.
MONDAY THROUGH TUESDAY...A BROAD SURFACE HIGH PRESSURE SYSTEM AND
UPPER LEVEL 500MB RIDGE WILL BUILD FROM NEAR HUDSON BAY SOUTHWARD
INTO MUCH OF THE UPPER MISSISSIPPI VALLEY THROUGH MONDAY
NIGHT...ALLOWING FOR COOL AND DRY WEATHER TO BUILD INTO THE REGION.
AT THE SAME TIME AN UPPER LEVEL TROUGH IS PROGGED TO FORM OVER
WESTERN CANADA. THE GFS/EC AGAIN HAVE INTENSITY AND PLACEMENT ISSUES
FOR THIS LOW...WITH THE GFS STRONGER AND MORE PROGRESSIVE...PLACING
THE THROUGH OVER THE UPPER PENINSULA BY LATE TUESDAY MORNING. THE EC
KEEPS THE TROUGH TO THE WEST OF THE AREA...OVER THE NORTHERN
PLAINS...THROUGH TUESDAY EVENING. WITH LOWER THAN NORMAL
CONFIDENCE...WILL STICK WITH MODEL CONSENSUS FOR THIS TIME FRAME.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 740 PM EDT TUE MAY 28 2013
WITH ABUNDANT SFC-750 MB MOISTURE IN ADVANCE OF A SFC WARM FRONT IN
THE LOWER GREATT LAKES MOVING SLOWLY TO THE N...EXPECT SLOWLY
DETERIORATING CONDITIONS AT THE TAF SITES THROUGH TONIGHT IN THE
PRESENCE OF DIURNAL COOLING. SOME LIGHT SHOWERS ARE ALSO POSSIBLE
THIS EVENING AT SAW BUT SHOULD BE LIGHT ENOUGH NOT TO AFFECT
CIG/VSBY. IFR CONDITIONS ARE POSSIBLE AT ALL 3 SITES BEFORE DAYTIME
HEATING/MIXING ON WED RESULTS IN SOME IMPROVEMENT AS WEAK SFC HIGH
PRES MOVES INTO THE AREA.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 352 PM EDT TUE MAY 28 2013
WITH GENERALLY WEAK PRES GRADIENT AND STABLE CONDITIONS OVER LAKE
SUPERIOR...EXPECT WINDS TO BE UNDER 25KT THRU THE WEEK. ALTHOUGH
SOME FOG MAY DEVELOP LATE TONIGHT OVER THE LAKE WITH GRADUALLY
INCREASING LOW LEVEL MOISTURE...THICKER AND MORE WIDESPREAD FOG IS
NOT LIKELY UNTIL SOME APPRECIABLE RAINFALL OCCURS OVER THE
LAKE...PROBABLY NOT UNTIL WED NIGHT. AT LEAST PATCHY DENSE FOG IS
THEN LIKELY INTO SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KEC
AVIATION...JLB
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
116 PM EDT MON MAY 27 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 532 AM EDT MON MAY 27 2013
WATER VAROR IMAGERY AND RUC ANALYSIS SHOW THE BEGINNINGS OF AN
ACTIVE PATTERN SHAPING UP FOR THE UPPER GREAT LAKES THIS WEEK. MEAN
TROF SETTLING INTO THE WRN CONUS THRU MIDWEEK AND THEN SLOW SHIFTING
E WILL SEND NMRS SHORTWAVES THRU THE CNTRL CONUS AND INTO THE GREAT
LAKES. MODELS WILL NO DOUBT STRUGGLE WITH THE CONVECTION ASSOCIATED
WITH THE WAVES...AND THE FCST WILL HAVE MUCH MORE THAN NORMAL
UNCERTAINTY BEYOND THE SHORT TERM. SEVERAL CLUSTERS OF SHRA/TSRA
HAVE BEEN OCCURRING FROM THE DAKOTAS TO THE OHIO VALLEY DURING THE
NIGHT...A SIGN OF THE ACTIVE PATTERN EVOLVING THIS WEEK.
MEANWHILE...DRY AIR CONTINUES TO LINGER OVER THE UPPER LAKES (NOTE
THE DRY 00Z SOUNDINGS FROM KGRB/KAPX).
THERE ARE 3 SHORTWAVES OF INTEREST FOR THE SHORT TERM. THE FIRST OF
IS OVER ERN MT/WRN ND...THE SECOND IS OVER WRN IA AND THE THIRD IS
OVER THE SRN ROCKIES. THE FIRST WAVE IS PRODUCING CONVECTION OVER
THE WRN DAKOTAS. THIS WAVE IS ON A TRACK TO LIFT NE AROUND THE RIDGE
EXTENDING N THRU THE MISSISSIPPI VALLEY TOWARD HUDSON BAY...AND WILL
NOT BE A FACTOR HERE. THE SECOND WAVE SHOULD WEAKEN AS IT CUTS THRU
THE RIDGE...AND ITS ASSOCIATED CONVECTION SHOULD ALSO WEAKEN AS IT
OUTRUNS THE INSTABILITY POOL OVER THE PLAINS. THE THIRD WAVE WILL
HELP STRENGTHEN THE LOW LEVEL JET TONIGHT AS IT MOVES OUT ACROSS THE
PLAINS. WITH FRONTAL BOUNDARY CURRENTLY WELL TO THE SW AND S AND NOT
LIKELY TO MAKE MUCH PROGRESS TODAY...DRY WEATHER WILL BE THE RULE
TODAY AND PROBABLY RIGHT INTO THE EVENING HRS. ALL MODELS WITH THE
EXCEPTION OF THE GEM HAVE TRENDED NOTABLY SLOWER ADVANCING PCPN
TOWARD UPPER MI. WILL THUS RUN WITH A DRY FCST INTO THE EVENING.
TONIGHT...STRENGTHENING LOW-LEVEL JET IN RESPONSE TO AFOREMENTIONED
SHORTWAVE WILL HELP GENERATE MORE SHRA/TSRA ACROSS THE PLAINS TOWARD
THE UPPER MISSISSIPPI VALLEY/WRN LAKES. DIFFICULT TO SAY HOW FAR N
AND E PCPN WILL ADVANCE...BUT WITH ADVANCING WARM FRONT STILL A GOOD
DISTANCE TO THE SW...WOULD EXPECT BULK OF SHRA/TSRA ACTIVITY TO
REMAIN TO THE S AND SW. HOWEVER...NRN FRINGES OF PCPN MAY STILL
SPREAD FAR ENOUGH N TO AFFECT AT LEAST SRN UPPER MI...AND WILL
INCLUDE SCHC/CHC POPS OVERNIGHT.
ALTHOUGH CI BLOWOFF FROM CONVECTION OVER ERN NEBRASKA/WRN IA IS
CURRENTLY SPREADING INTO UPPER MI...EXPECT THESE HIGH CLOUDS TO THIN
OUT SOME DURING THE DAY AS CONVECTION WEAKENS. SO...THERE SHOULD
STILL BE FAIRLY STRONG HEATING TODAY AND THUS DEEP MIXING TO BRING
DRIER AIR DOWN TO THE SFC. DWPTS SHOULD FALL TO THE LOW/MID 30S THIS
AFTN...PERHAPS LOWER OVER THE CNTRL/E BASED ON POTENTIAL MIXING
HEIGHTS. WITH HIGH TEMPS UP AROUND 70F IN THE INTERIOR...RH SHOULD
BOTTOM OUT IN THE 25-30PCT RANGE W AND 20-25PCT RANGE E. WINDS WILL
BE A LITTLE STRONGER TODAY AS SFC HIGH PRES RIDGE DRIFTS FARTHER E
OF THE AREA. WILL PROBABLY SEE AFTN GUSTS AROUND 20MPH OVER THE W
AND CNTRL AND 15MPH OVER THE E. WITH THE RECENT DRY DAYS...FIRE WX
CONCERNS WILL BE HIGHER TODAY GIVEN THE LOW RH AND A LITTLE STRONGER
WIND.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 532 AM EDT MON MAY 27 2013
TRICKY FORECAST FOR TUESDAY INTO TUESDAY NIGHT CONCERNING
PRECIPITATION CHANCES. OVERALL...SHORT WAVE ENERGY CURRENTLY MOVING
INTO THE CENTRAL PLAINS WILL MOVE INTO THE WESTERN GREAT LAKES
REGION LATER TONIGHT INTO TUESDAY. MEANWHILE...A WARM FRONTAL
BOUNDARY WILL MOVE NORTH INTO THE UPPER GREAT LAKES ON TUESDAY. THIS
WARM FRONT WILL LIKELY SERVE AS THE FOCUS FOR SHOWERS AND
THUNDERSTORMS...SIMILAR TO WHAT IT IS DOING THIS MORNING. THE
PROBLEM IS THAT THE NWP ARE HANDLING THIS WARM FRONT RATHER
POORLY...ALONG WITH THE 850MB JET THAT INTERSECTS THE FRONT. THE 12Z
ECMWF IS BY FAR THE FARTHEST WEST WITH THE LLJ AND ASSOCIATED
PCPN...PLACING THE HEAVIER PCPN ACROSS THE WESTERN LAKE AND WESTERN
UPPER MICHIGAN LATE TONIGHT INTO TUESDAY (ALTHOUGH THE 00Z ECMWF HAS
TRENDED AWAY FROM THIS SOLN). NOT SURE IF THE 12Z RUN MAKES SENSE AS
THE PCPN SEEMS TO RACE OUT AHEAD OF THE PRIMARY WARM FRONT.
MEANWHILE...THE NAM AND GFS CONTINUE TO BE SLOWER WITH PCPN MOVING
INTO THE AREA (WITH THE GFS BEING EVEN SLOWER)...BUT THEY KEEP THE
PCPN TIED TO THE FRONT...WITH THE HEAVIEST PCPN FURTHER SOUTH INTO
WISCONSIN WHERE THE LLJ IS JUSXTAPOSITIONED WITH THE BETTER
INSTABILITY. FINALLY...THE REGIONAL GEM IS SIMILAR WITH THE HEAVIEST
PCPN WELL SOUTH OF THE AREA BUT IT SPREADS PCPN INTO UPPER MICHIGAN
TOO FAST AND WELL AHEAD OF THE WARM FRONT. HAVE OPTED TO TREND
TOWARD A SLOWER NAM/GFS COMPROMISE SOLN WITH LIKELY POPS INTO
SOUTHERN UPPER MICH TUE MORNING...THEN SPREADING NORTH/EAST DURING
THE DAY AS THE WARM FRONT LIFTS NORTH. THE WESTERN AREAS WILL ALSO
TEND TO DRY OUT LATER IN THE DAY BEHIND THE SHORT WAVE. NOT TERRIBLY
IMPRESSED WITH THUNDER CHANCES ON TUESDAY. WITH THE SLOWER MOVEMENT
OF THE WARM FRONT...THE BEST INSTABILITY WILL REMAIN IN WISCONSIN.
SIMPLY DUE TO THE FORCING ALONG THE FRONT...CANNOT COMPLETELY RULE
OUT THUNDER BUT THE EXPECTATION IS THAT THE BEST THUNDER CHANCES
WOULD STAY ACROSS THE FAR SOUTH CLOSER TO THE BETTER INSTABILITY.
SHOULD END UP BEING A GENERALLY QUIET TUESDAY NIGHT AND WEDNESDAY
MORNING ACROSS THE AREA WITH UPPER AND SFC RIDGING ACROSS THE AREA.
WILL LIKELY BE A LITTLE MUGGY WITH THE AREA BEING IN THE WARM SECTOR
AND DEWPOINTS IN THE UPPER 50S. BUT GIVEN LACK OF FORCING OVERNIGHT
WILL GO WITH A DRY FORECAST AFTER ANY REMAINING SHOWERS/STORMS EXIT
EAST. ON WEDNESDAY...POPS WERE LOWERED WITH LACK OF ANY SIGNIFICANT
FOCUS FOR THUNDERSTORMS DESPITE MLCAPE VALUES OF 1000-1500 J/KG.
BETTER FOCUS FOR STORMS WITH THE NOSE OF THE 50KT LOW LEVEL JET AND
DEEP MOISTURE TRANSPORT INTO THE AREA EXPECTED WEDNESDAY NIGHT. THIS
MAY BE THE MOST LIKELY PERIOD FOR STRONG/SEVERE STORMS WITH FORWARD
PROPOGATING STORMS LIKELY MOVING INTO THE AREA FROM WISCONSIN.
FOR THE THU-SUNDAY PERIOD...THE AREA WILL BE FIRMLY IN THE WARM
SECTOR ON THURSDAY...AS THE LOW LEVEL JET BACKS TO A MORE SOUTHERLY
DIRECTION AND THE NOSE FOCUSES OVER NW WISCONSIN. EXPECT MORE
CONVECTION TO DEVELOP IN THIS AREA THURSDAY AND MOVE INTO UPPER
MICHIGAN DURING THE AFTN AND EVENING HOURS AS THE GFS AND 00Z ECMWF
ARE IN GOOD AGREEMENT IN SHOWING ANOTHER SHORT WAVE MOVING ACROSS
THE AREA. THE UPPER TROUGH AND SURFACE LOW FINALLY MOVES EAST
STARTING FRIDAY WITH THE SYSTEM MOVING ACROSS THE AREA BY SATURDAY.
WILL CONTINUE WITH CHANCES FOR SHOWERS AND THUNDERSTORMS THROUGH
SATURDAY. ANOTHER WARM AND MUGGY DAY ON FRIDAY...THEN TURNING COOLER
BY SUNDAY AS 850MB TEMPS DROP TO +6C BEHIND THE SYSTEM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1253 PM EDT MON MAY 27 2013
A HIGH PRES RIDGE WILL PERSIST OVER THE UPPER GREAT LAKES GENERALLY
MAINTAINING THE LOW-LVL DRY AIRMASS AND VFR CONDITIONS FOR KIWD/KCMX/KSAW
THROUGH THIS FCST PERIOD. A WARM FRONT OVER THE PLAINS WILL BE MOVING
N TONIGHT AND EARLY TUE...BUT GUIDANCE CONTINUES TO TREND TOWARD
KEEPING SHRA ASSOCIATED WITH FRONTAL BOUNDARY GENERALLY S OF THE
AREA. A FEW SHRA SKIRTING NORTH OF THE FRONTAL BOUNDARY COULD BRUSH
KSAW WITH SOME LIGHT -SHRA BY LATE TUE MORNING. SOUTHEASTERLY WINDS
WILL INCREASE THIS AFTERNOON WITH GUSTS APPROACHING 20 KT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 532 AM EDT MON MAY 27 2013
WITH GENERALLY WEAK PRES GRADIENT AND STABLE CONDITIONS OVER LAKE
SUPERIOR...EXPECT WINDS TO BE UNDER 25KT THRU THE WEEK. HOWEVER...
WITH THE POTENTIAL FOR CLUSTERS OF SHRA/TSRA TO PASS ACROSS/NEAR THE
UPPER GREAT LAKES...THERE COULD BE SHORT PERIODS OF ENHANCED WINDS
AT TIMES (STRONGER SE WINDS OVER ERN LAKE SUPERIOR AND STRONGER NE
WINDS OVER WRN LAKE SUPERIOR). ONCE SOME RAINFALL OCCURS OVER THE
LAKE...FOG WILL LIKELY DEVELOP...AND IT COULD BECOME DENSE MID TO
LATE WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...MRD
AVIATION...VOSS
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
723 AM EDT MON MAY 27 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 532 AM EDT MON MAY 27 2013
WATER VAROR IMAGERY AND RUC ANALYSIS SHOW THE BEGINNINGS OF AN
ACTIVE PATTERN SHAPING UP FOR THE UPPER GREAT LAKES THIS WEEK. MEAN
TROF SETTLING INTO THE WRN CONUS THRU MIDWEEK AND THEN SLOW SHIFTING
E WILL SEND NMRS SHORTWAVES THRU THE CNTRL CONUS AND INTO THE GREAT
LAKES. MODELS WILL NO DOUBT STRUGGLE WITH THE CONVECTION ASSOCIATED
WITH THE WAVES...AND THE FCST WILL HAVE MUCH MORE THAN NORMAL
UNCERTAINTY BEYOND THE SHORT TERM. SEVERAL CLUSTERS OF SHRA/TSRA
HAVE BEEN OCCURRING FROM THE DAKOTAS TO THE OHIO VALLEY DURING THE
NIGHT...A SIGN OF THE ACTIVE PATTERN EVOLVING THIS WEEK.
MEANWHILE...DRY AIR CONTINUES TO LINGER OVER THE UPPER LAKES (NOTE
THE DRY 00Z SOUNDINGS FROM KGRB/KAPX).
THERE ARE 3 SHORTWAVES OF INTEREST FOR THE SHORT TERM. THE FIRST OF
IS OVER ERN MT/WRN ND...THE SECOND IS OVER WRN IA AND THE THIRD IS
OVER THE SRN ROCKIES. THE FIRST WAVE IS PRODUCING CONVECTION OVER
THE WRN DAKOTAS. THIS WAVE IS ON A TRACK TO LIFT NE AROUND THE RIDGE
EXTENDING N THRU THE MISSISSIPPI VALLEY TOWARD HUDSON BAY...AND WILL
NOT BE A FACTOR HERE. THE SECOND WAVE SHOULD WEAKEN AS IT CUTS THRU
THE RIDGE...AND ITS ASSOCIATED CONVECTION SHOULD ALSO WEAKEN AS IT
OUTRUNS THE INSTABILITY POOL OVER THE PLAINS. THE THIRD WAVE WILL
HELP STRENGTHEN THE LOW LEVEL JET TONIGHT AS IT MOVES OUT ACROSS THE
PLAINS. WITH FRONTAL BOUNDARY CURRENTLY WELL TO THE SW AND S AND NOT
LIKELY TO MAKE MUCH PROGRESS TODAY...DRY WEATHER WILL BE THE RULE
TODAY AND PROBABLY RIGHT INTO THE EVENING HRS. ALL MODELS WITH THE
EXCEPTION OF THE GEM HAVE TRENDED NOTABLY SLOWER ADVANCING PCPN
TOWARD UPPER MI. WILL THUS RUN WITH A DRY FCST INTO THE EVENING.
TONIGHT...STRENGTHENING LOW-LEVEL JET IN RESPONSE TO AFOREMENTIONED
SHORTWAVE WILL HELP GENERATE MORE SHRA/TSRA ACROSS THE PLAINS TOWARD
THE UPPER MISSISSIPPI VALLEY/WRN LAKES. DIFFICULT TO SAY HOW FAR N
AND E PCPN WILL ADVANCE...BUT WITH ADVANCING WARM FRONT STILL A GOOD
DISTANCE TO THE SW...WOULD EXPECT BULK OF SHRA/TSRA ACTIVITY TO
REMAIN TO THE S AND SW. HOWEVER...NRN FRINGES OF PCPN MAY STILL
SPREAD FAR ENOUGH N TO AFFECT AT LEAST SRN UPPER MI...AND WILL
INCLUDE SCHC/CHC POPS OVERNIGHT.
ALTHOUGH CI BLOWOFF FROM CONVECTION OVER ERN NEBRASKA/WRN IA IS
CURRENTLY SPREADING INTO UPPER MI...EXPECT THESE HIGH CLOUDS TO THIN
OUT SOME DURING THE DAY AS CONVECTION WEAKENS. SO...THERE SHOULD
STILL BE FAIRLY STRONG HEATING TODAY AND THUS DEEP MIXING TO BRING
DRIER AIR DOWN TO THE SFC. DWPTS SHOULD FALL TO THE LOW/MID 30S THIS
AFTN...PERHAPS LOWER OVER THE CNTRL/E BASED ON POTENTIAL MIXING
HEIGHTS. WITH HIGH TEMPS UP AROUND 70F IN THE INTERIOR...RH SHOULD
BOTTOM OUT IN THE 25-30PCT RANGE W AND 20-25PCT RANGE E. WINDS WILL
BE A LITTLE STRONGER TODAY AS SFC HIGH PRES RIDGE DRIFTS FARTHER E
OF THE AREA. WILL PROBABLY SEE AFTN GUSTS AROUND 20MPH OVER THE W
AND CNTRL AND 15MPH OVER THE E. WITH THE RECENT DRY DAYS...FIRE WX
CONCERNS WILL BE HIGHER TODAY GIVEN THE LOW RH AND A LITTLE STRONGER
WIND.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 532 AM EDT MON MAY 27 2013
TRICKY FORECAST FOR TUESDAY INTO TUESDAY NIGHT CONCERNING
PRECIPITATION CHANCES. OVERALL...SHORT WAVE ENERGY CURRENTLY MOVING
INTO THE CENTRAL PLAINS WILL MOVE INTO THE WESTERN GREAT LAKES
REGION LATER TONIGHT INTO TUESDAY. MEANWHILE...A WARM FRONTAL
BOUNDARY WILL MOVE NORTH INTO THE UPPER GREAT LAKES ON TUESDAY. THIS
WARM FRONT WILL LIKELY SERVE AS THE FOCUS FOR SHOWERS AND
THUNDERSTORMS...SIMILAR TO WHAT IT IS DOING THIS MORNING. THE
PROBLEM IS THAT THE NWP ARE HANDLING THIS WARM FRONT RATHER
POORLY...ALONG WITH THE 850MB JET THAT INTERSECTS THE FRONT. THE 12Z
ECMWF IS BY FAR THE FARTHEST WEST WITH THE LLJ AND ASSOCIATED
PCPN...PLACING THE HEAVIER PCPN ACROSS THE WESTERN LAKE AND WESTERN
UPPER MICHIGAN LATE TONIGHT INTO TUESDAY (ALTHOUGH THE 00Z ECMWF HAS
TRENDED AWAY FROM THIS SOLN). NOT SURE IF THE 12Z RUN MAKES SENSE AS
THE PCPN SEEMS TO RACE OUT AHEAD OF THE PRIMARY WARM FRONT.
MEANWHILE...THE NAM AND GFS CONTINUE TO BE SLOWER WITH PCPN MOVING
INTO THE AREA (WITH THE GFS BEING EVEN SLOWER)...BUT THEY KEEP THE
PCPN TIED TO THE FRONT...WITH THE HEAVIEST PCPN FURTHER SOUTH INTO
WISCONSIN WHERE THE LLJ IS JUSXTAPOSITIONED WITH THE BETTER
INSTABILITY. FINALLY...THE REGIONAL GEM IS SIMILAR WITH THE HEAVIEST
PCPN WELL SOUTH OF THE AREA BUT IT SPREADS PCPN INTO UPPER MICHIGAN
TOO FAST AND WELL AHEAD OF THE WARM FRONT. HAVE OPTED TO TREND
TOWARD A SLOWER NAM/GFS COMPROMISE SOLN WITH LIKELY POPS INTO
SOUTHERN UPPER MICH TUE MORNING...THEN SPREADING NORTH/EAST DURING
THE DAY AS THE WARM FRONT LIFTS NORTH. THE WESTERN AREAS WILL ALSO
TEND TO DRY OUT LATER IN THE DAY BEHIND THE SHORT WAVE. NOT TERRIBLY
IMPRESSED WITH THUNDER CHANCES ON TUESDAY. WITH THE SLOWER MOVEMENT
OF THE WARM FRONT...THE BEST INSTABILITY WILL REMAIN IN WISCONSIN.
SIMPLY DUE TO THE FORCING ALONG THE FRONT...CANNOT COMPLETELY RULE
OUT THUNDER BUT THE EXPECTATION IS THAT THE BEST THUNDER CHANCES
WOULD STAY ACROSS THE FAR SOUTH CLOSER TO THE BETTER INSTABILITY.
SHOULD END UP BEING A GENERALLY QUIET TUESDAY NIGHT AND WEDNESDAY
MORNING ACROSS THE AREA WITH UPPER AND SFC RIDGING ACROSS THE AREA.
WILL LIKELY BE A LITTLE MUGGY WITH THE AREA BEING IN THE WARM SECTOR
AND DEWPOINTS IN THE UPPER 50S. BUT GIVEN LACK OF FORCING OVERNIGHT
WILL GO WITH A DRY FORECAST AFTER ANY REMAINING SHOWERS/STORMS EXIT
EAST. ON WEDNESDAY...POPS WERE LOWERED WITH LACK OF ANY SIGNIFICANT
FOCUS FOR THUNDERSTORMS DESPITE MLCAPE VALUES OF 1000-1500 J/KG.
BETTER FOCUS FOR STORMS WITH THE NOSE OF THE 50KT LOW LEVEL JET AND
DEEP MOISTURE TRANSPORT INTO THE AREA EXPECTED WEDNESDAY NIGHT. THIS
MAY BE THE MOST LIKELY PERIOD FOR STRONG/SEVERE STORMS WITH FORWARD
PROPOGATING STORMS LIKELY MOVING INTO THE AREA FROM WISCONSIN.
FOR THE THU-SUNDAY PERIOD...THE AREA WILL BE FIRMLY IN THE WARM
SECTOR ON THURSDAY...AS THE LOW LEVEL JET BACKS TO A MORE SOUTHERLY
DIRECTION AND THE NOSE FOCUSES OVER NW WISCONSIN. EXPECT MORE
CONVECTION TO DEVELOP IN THIS AREA THURSDAY AND MOVE INTO UPPER
MICHIGAN DURING THE AFTN AND EVENING HOURS AS THE GFS AND 00Z ECMWF
ARE IN GOOD AGREEMENT IN SHOWING ANOTHER SHORT WAVE MOVING ACROSS
THE AREA. THE UPPER TROUGH AND SURFACE LOW FINALLY MOVES EAST
STARTING FRIDAY WITH THE SYSTEM MOVING ACROSS THE AREA BY SATURDAY.
WILL CONTINUE WITH CHANCES FOR SHOWERS AND THUNDERSTORMS THROUGH
SATURDAY. ANOTHER WARM AND MUGGY DAY ON FRIDAY...THEN TURNING COOLER
BY SUNDAY AS 850MB TEMPS DROP TO +6C BEHIND THE SYSTEM.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 722 AM EDT MON MAY 27 2013
ALTHOUGH HIGH PRES OVER THE GREAT LAKES REGION WILL BE DRIFTING E...
ASSOCIATED DRY LOW LEVEL AIR MASS WILL LIKELY LINGER AND MAINTAIN
VFR CONDITIONS AT KIWD/KCMX/KSAW THROUGH THIS FCST PERIOD. A WARM
FRONT OVER THE PLAINS WILL BE MOVING N TONIGHT...BUT LATEST GUIDANCE
IS TRENDING TOWARD KEEPING SHRA ASSOCIATED WITH FRONTAL BOUNDARY TO
THE S OF THE AREA. SOUTHEASTERLY WINDS WILL INCREASE TODAY WITH
GUSTS APPROACHING 20 KT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 532 AM EDT MON MAY 27 2013
WITH GENERALLY WEAK PRES GRADIENT AND STABLE CONDITIONS OVER LAKE
SUPERIOR...EXPECT WINDS TO BE UNDER 25KT THRU THE WEEK. HOWEVER...
WITH THE POTENTIAL FOR CLUSTERS OF SHRA/TSRA TO PASS ACROSS/NEAR THE
UPPER GREAT LAKES...THERE COULD BE SHORT PERIODS OF ENHANCED WINDS
AT TIMES (STRONGER SE WINDS OVER ERN LAKE SUPERIOR AND STRONGER NE
WINDS OVER WRN LAKE SUPERIOR). ONCE SOME RAINFALL OCCURS OVER THE
LAKE...FOG WILL LIKELY DEVELOP...AND IT COULD BECOME DENSE MID TO
LATE WEEK.
&&
.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 MARQUETTE MI
535 AM EDT MON MAY 27 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 532 AM EDT MON MAY 27 2013
WATER VAROR IMAGERY AND RUC ANALYSIS SHOW THE BEGINNINGS OF AN
ACTIVE PATTERN SHAPING UP FOR THE UPPER GREAT LAKES THIS WEEK. MEAN
TROF SETTLING INTO THE WRN CONUS THRU MIDWEEK AND THEN SLOW SHIFTING
E WILL SEND NMRS SHORTWAVES THRU THE CNTRL CONUS AND INTO THE GREAT
LAKES. MODELS WILL NO DOUBT STRUGGLE WITH THE CONVECTION ASSOCIATED
WITH THE WAVES...AND THE FCST WILL HAVE MUCH MORE THAN NORMAL
UNCERTAINTY BEYOND THE SHORT TERM. SEVERAL CLUSTERS OF SHRA/TSRA
HAVE BEEN OCCURRING FROM THE DAKOTAS TO THE OHIO VALLEY DURING THE
NIGHT...A SIGN OF THE ACTIVE PATTERN EVOLVING THIS WEEK.
MEANWHILE...DRY AIR CONTINUES TO LINGER OVER THE UPPER LAKES (NOTE
THE DRY 00Z SOUNDINGS FROM KGRB/KAPX).
THERE ARE 3 SHORTWAVES OF INTEREST FOR THE SHORT TERM. THE FIRST OF
IS OVER ERN MT/WRN ND...THE SECOND IS OVER WRN IA AND THE THIRD IS
OVER THE SRN ROCKIES. THE FIRST WAVE IS PRODUCING CONVECTION OVER
THE WRN DAKOTAS. THIS WAVE IS ON A TRACK TO LIFT NE AROUND THE RIDGE
EXTENDING N THRU THE MISSISSIPPI VALLEY TOWARD HUDSON BAY...AND WILL
NOT BE A FACTOR HERE. THE SECOND WAVE SHOULD WEAKEN AS IT CUTS THRU
THE RIDGE...AND ITS ASSOCIATED CONVECTION SHOULD ALSO WEAKEN AS IT
OUTRUNS THE INSTABILITY POOL OVER THE PLAINS. THE THIRD WAVE WILL
HELP STRENGTHEN THE LOW LEVEL JET TONIGHT AS IT MOVES OUT ACROSS THE
PLAINS. WITH FRONTAL BOUNDARY CURRENTLY WELL TO THE SW AND S AND NOT
LIKELY TO MAKE MUCH PROGRESS TODAY...DRY WEATHER WILL BE THE RULE
TODAY AND PROBABLY RIGHT INTO THE EVENING HRS. ALL MODELS WITH THE
EXCEPTION OF THE GEM HAVE TRENDED NOTABLY SLOWER ADVANCING PCPN
TOWARD UPPER MI. WILL THUS RUN WITH A DRY FCST INTO THE EVENING.
TONIGHT...STRENGTHENING LOW-LEVEL JET IN RESPONSE TO AFOREMENTIONED
SHORTWAVE WILL HELP GENERATE MORE SHRA/TSRA ACROSS THE PLAINS TOWARD
THE UPPER MISSISSIPPI VALLEY/WRN LAKES. DIFFICULT TO SAY HOW FAR N
AND E PCPN WILL ADVANCE...BUT WITH ADVANCING WARM FRONT STILL A GOOD
DISTANCE TO THE SW...WOULD EXPECT BULK OF SHRA/TSRA ACTIVITY TO
REMAIN TO THE S AND SW. HOWEVER...NRN FRINGES OF PCPN MAY STILL
SPREAD FAR ENOUGH N TO AFFECT AT LEAST SRN UPPER MI...AND WILL
INCLUDE SCHC/CHC POPS OVERNIGHT.
ALTHOUGH CI BLOWOFF FROM CONVECTION OVER ERN NEBRASKA/WRN IA IS
CURRENTLY SPREADING INTO UPPER MI...EXPECT THESE HIGH CLOUDS TO THIN
OUT SOME DURING THE DAY AS CONVECTION WEAKENS. SO...THERE SHOULD
STILL BE FAIRLY STRONG HEATING TODAY AND THUS DEEP MIXING TO BRING
DRIER AIR DOWN TO THE SFC. DWPTS SHOULD FALL TO THE LOW/MID 30S THIS
AFTN...PERHAPS LOWER OVER THE CNTRL/E BASED ON POTENTIAL MIXING
HEIGHTS. WITH HIGH TEMPS UP AROUND 70F IN THE INTERIOR...RH SHOULD
BOTTOM OUT IN THE 25-30PCT RANGE W AND 20-25PCT RANGE E. WINDS WILL
BE A LITTLE STRONGER TODAY AS SFC HIGH PRES RIDGE DRIFTS FARTHER E
OF THE AREA. WILL PROBABLY SEE AFTN GUSTS AROUND 20MPH OVER THE W
AND CNTRL AND 15MPH OVER THE E. WITH THE RECENT DRY DAYS...FIRE WX
CONCERNS WILL BE HIGHER TODAY GIVEN THE LOW RH AND A LITTLE STRONGER
WIND.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 532 AM EDT MON MAY 27 2013
TRICKY FORECAST FOR TUESDAY INTO TUESDAY NIGHT CONCERNING
PRECIPITATION CHANCES. OVERALL...SHORT WAVE ENERGY CURRENTLY MOVING
INTO THE CENTRAL PLAINS WILL MOVE INTO THE WESTERN GREAT LAKES
REGION LATER TONIGHT INTO TUESDAY. MEANWHILE...A WARM FRONTAL
BOUNDARY WILL MOVE NORTH INTO THE UPPER GREAT LAKES ON TUESDAY. THIS
WARM FRONT WILL LIKELY SERVE AS THE FOCUS FOR SHOWERS AND
THUNDERSTORMS...SIMILAR TO WHAT IT IS DOING THIS MORNING. THE
PROBLEM IS THAT THE NWP ARE HANDLING THIS WARM FRONT RATHER
POORLY...ALONG WITH THE 850MB JET THAT INTERSECTS THE FRONT. THE 12Z
ECMWF IS BY FAR THE FARTHEST WEST WITH THE LLJ AND ASSOCIATED
PCPN...PLACING THE HEAVIER PCPN ACROSS THE WESTERN LAKE AND WESTERN
UPPER MICHIGAN LATE TONIGHT INTO TUESDAY (ALTHOUGH THE 00Z ECMWF HAS
TRENDED AWAY FROM THIS SOLN). NOT SURE IF THE 12Z RUN MAKES SENSE AS
THE PCPN SEEMS TO RACE OUT AHEAD OF THE PRIMARY WARM FRONT.
MEANWHILE...THE NAM AND GFS CONTINUE TO BE SLOWER WITH PCPN MOVING
INTO THE AREA (WITH THE GFS BEING EVEN SLOWER)...BUT THEY KEEP THE
PCPN TIED TO THE FRONT...WITH THE HEAVIEST PCPN FURTHER SOUTH INTO
WISCONSIN WHERE THE LLJ IS JUSXTAPOSITIONED WITH THE BETTER
INSTABILITY. FINALLY...THE REGIONAL GEM IS SIMILAR WITH THE HEAVIEST
PCPN WELL SOUTH OF THE AREA BUT IT SPREADS PCPN INTO UPPER MICHIGAN
TOO FAST AND WELL AHEAD OF THE WARM FRONT. HAVE OPTED TO TREND
TOWARD A SLOWER NAM/GFS COMPROMISE SOLN WITH LIKELY POPS INTO
SOUTHERN UPPER MICH TUE MORNING...THEN SPREADING NORTH/EAST DURING
THE DAY AS THE WARM FRONT LIFTS NORTH. THE WESTERN AREAS WILL ALSO
TEND TO DRY OUT LATER IN THE DAY BEHIND THE SHORT WAVE. NOT TERRIBLY
IMPRESSED WITH THUNDER CHANCES ON TUESDAY. WITH THE SLOWER MOVEMENT
OF THE WARM FRONT...THE BEST INSTABILITY WILL REMAIN IN WISCONSIN.
SIMPLY DUE TO THE FORCING ALONG THE FRONT...CANNOT COMPLETELY RULE
OUT THUNDER BUT THE EXPECTATION IS THAT THE BEST THUNDER CHANCES
WOULD STAY ACROSS THE FAR SOUTH CLOSER TO THE BETTER INSTABILITY.
SHOULD END UP BEING A GENERALLY QUIET TUESDAY NIGHT AND WEDNESDAY
MORNING ACROSS THE AREA WITH UPPER AND SFC RIDGING ACROSS THE AREA.
WILL LIKELY BE A LITTLE MUGGY WITH THE AREA BEING IN THE WARM SECTOR
AND DEWPOINTS IN THE UPPER 50S. BUT GIVEN LACK OF FORCING OVERNIGHT
WILL GO WITH A DRY FORECAST AFTER ANY REMAINING SHOWERS/STORMS EXIT
EAST. ON WEDNESDAY...POPS WERE LOWERED WITH LACK OF ANY SIGNIFICANT
FOCUS FOR THUNDERSTORMS DESPITE MLCAPE VALUES OF 1000-1500 J/KG.
BETTER FOCUS FOR STORMS WITH THE NOSE OF THE 50KT LOW LEVEL JET AND
DEEP MOISTURE TRANSPORT INTO THE AREA EXPECTED WEDNESDAY NIGHT. THIS
MAY BE THE MOST LIKELY PERIOD FOR STRONG/SEVERE STORMS WITH FORWARD
PROPOGATING STORMS LIKELY MOVING INTO THE AREA FROM WISCONSIN.
FOR THE THU-SUNDAY PERIOD...THE AREA WILL BE FIRMLY IN THE WARM
SECTOR ON THURSDAY...AS THE LOW LEVEL JET BACKS TO A MORE SOUTHERLY
DIRECTION AND THE NOSE FOCUSES OVER NW WISCONSIN. EXPECT MORE
CONVECTION TO DEVELOP IN THIS AREA THURSDAY AND MOVE INTO UPPER
MICHIGAN DURING THE AFTN AND EVENING HOURS AS THE GFS AND 00Z ECMWF
ARE IN GOOD AGREEMENT IN SHOWING ANOTHER SHORT WAVE MOVING ACROSS
THE AREA. THE UPPER TROUGH AND SURFACE LOW FINALLY MOVES EAST
STARTING FRIDAY WITH THE SYSTEM MOVING ACROSS THE AREA BY SATURDAY.
WILL CONTINUE WITH CHANCES FOR SHOWERS AND THUNDERSTORMS THROUGH
SATURDAY. ANOTHER WARM AND MUGGY DAY ON FRIDAY...THEN TURNING COOLER
BY SUNDAY AS 850MB TEMPS DROP TO +6C BEHIND THE SYSTEM.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 118 AM EDT MON MAY 27 2013
DRY LOW LEVEL AIR MASS ASSOCIATED WITH HIGH PRES OVER THE GREAT
LAKES WILL RESULT IN VFR CONDITIONS AT KIWD/KCMX/KSAW THOUGH THIS
AFTERNOON. PCPN WITH AN APPROACHING WARM FRONT MAY MOVE IN TONIGHT
BUT CONFIDENCE IS NOT HIGH ENOUGH TO INCLUDE MENTION OF PCPN OR TSRA
IN THE TAF. SE WINDS WILL INCREASE TODAY BUT GUSTS SHOULD REMAIN BELOW
20 KT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 532 AM EDT MON MAY 27 2013
WITH GENERALLY WEAK PRES GRADIENT AND STABLE CONDITIONS OVER LAKE
SUPERIOR...EXPECT WINDS TO BE UNDER 25KT THRU THE WEEK. HOWEVER...
WITH THE POTENTIAL FOR CLUSTERS OF SHRA/TSRA TO PASS ACROSS/NEAR THE
UPPER GREAT LAKES...THERE COULD BE SHORT PERIODS OF ENHANCED WINDS
AT TIMES (STRONGER SE WINDS OVER ERN LAKE SUPERIOR AND STRONGER NE
WINDS OVER WRN LAKE SUPERIOR). ONCE SOME RAINFALL OCCURS OVER THE
LAKE...FOG WILL LIKELY DEVELOP...AND IT COULD BECOME DENSE MID TO
LATE WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...MRD
AVIATION...JLB
MARINE...ROLFSON
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1226 PM CDT MON MAY 27 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT MON MAY 27 2013
ONCE AGAIN DEALING WITH A COMPLEX FORECAST WITH THE SENSIBLE WEATHER
STRONGLY CONTROLLED BY MESOSCALE FACTORS...SOMETHING THE MODELS
TYPICALLY HAVE DIFFICULTY IN RESOLVING. THE CONVECTIVE SYSTEM
CURRENTLY EXTENDING THROUGH EASTERN MO HAS BEEN WEAKENING AND
SHRINKING OVER THE LAST FEW HOURS AS IT MOVES ESEWD TOWARDS THE MS
RIVER. I SEE NO REASON FOR THIS TREND NOT TO CONTINUE...WITH A
CONTINUED DECREASE IN INTENSITY AND COVERAGE AS IT OUTRUNS THE
INSTABILITY AND BETTER LOW LEVEL FORCING. ATTENTION THEN TURNS TO
THE MATURE BOW ECHO SYSTEM/MCS ACROSS WESTERN IOWA/SERN NEBRASKA.
THIS WELL-DEFINED SYSTEM IS BEING FEED BY A 40+KT SWLY LLJ WITH
MUCAPES OF 1500-2000 J/KG. VIRTUALLY ALL THE EXPLICIT CONVECTION
ALLOWING MODELS INCLUDING THE HRRR BRING THIS SYSTEM SEWD THIS
MORNING AND HAVE IT IMPACTING THE AREA ALONG AND NORTH OF
I-70...PRIMARILY THIS AFTERNOON. I`M NOT SURE ABOUT THE TIMING OR
THE EXACT STRUCTURE OF THE FINAL PRODUCT BUT THIS SCENARIO LOOKS
QUITE REASONABLE AND I HAVE LIKELY POPS OVER A MOST OF THE NRN
2/3RDS OF THE CWA. THE SYSTEM IS MOVING AT A PRETTY GOOD CLIP
RIGHT NOW AND PURE EXTRAPOLATION WOULD HAVE IT ENTERING THE NW
PORTION OF THE CWA 14Z OR SO...HOWEVER IT MAY BECOME MORE ELONGATED
WITH TIME. THE LONGER IT TAKES TO ENTER THE CWA...THE GREATER THE
OPPORTUNITY FOR THE AIR MASS AHEAD OF IT TO DESTABILIZE AND THEN FOR
THE SYSTEM AND ITS MESOSCALE BOUNDARY TO INTERACT WITH. IT COULD
POSE A LOCALLY HEAVY RAIN AND WIND THREAT DEPENDING ON ITS FINAL
INTENSITY.
NORTHERN PORTIONS OF MO INTO WEST CENTRAL IL LOOK ACTIVE AGAIN
TONIGHT. A SHORTWAVE WILL BE MOVING ENEWD FROM THE PLAINS INTO THE
MID/UPPER MS VALLEY PROVIDING LARGE SCALE ASCENT ALONG WITH
FORCING VIA A STOUT 50+ KT VEERING SWLY LLJ. THIS WILL PROVIDE
STRONG SUPPORT FOR AT LEAST ONE AND POSSIBLY SEVERAL MCSS WHICH
TRACK EASTWARD FROM THE CENTRAL PLAINS AND EFFECT PORTIONS OF NRN
MO. AGAIN THERE COULD BE A WIND AND HEAVY RAIN THREAT WITH ANY
SYSTEM.
GLASS
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 400 AM CDT MON MAY 27 2013
THE CHANCE OF SHOWERS AND THUNDERSTORMS LINGERS A BIT LONGER THAN
PREVIOUSLY FORECAST INTO TUESDAY AND TUESDAY NIGHT ACCOUNTING FOR
RESIDUAL BOUNDARIES FROM TONIGHTS ACTIVITY...HOWEVER OVERALL THE
AREA IMPACTED SHOULD BE SHRINKING AND TEMPERATURES WILL BE WARMING
TUESDAY AND WEDNESDAY AS A RIDGE BUILDS THRU THE ERN U.S. BY THE
LATER PART OF THE WEEK AND INTO THE WEEKEND WE GET BACK INTO AN
ACTIVE PATTERN AS A DEEP UPPER TROF SLOWLY PROGRESSES EASTWARD
INTO THE NATIONS MIDSECTION.
GLASS
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1213 PM CDT MON MAY 27 2013
A LINE OF THUNDERSTORMS WILL MOVE ACROSS THE REGION THIS AFTN.
BRIEF PDS OF IFR VSBYS ARE EXPECTED DUE TO HEAVY RAINFALL. WINDS
WILL TURN NWLY FOR A FEW HOURS AFTER THE STORMS MOVE THROUGH
FOLLOWED BY A RETURN TO PREVAILING SLY FLOW. THERE IS A GREAT
DEAL OF UNCERTAINTY REGARDING CONVECTIVE TRENDS FOR LATE TONIGHT
BUT PCPN CHCS APPEAR TO BE HIGHEST AT KUIN. STRONGER WINDS SHOULD
MIX DOWN TO THE SFC TOMORROW AND PRODUCE WIND GUSTS OF 20-25 KTS.
SPECIFICS FOR KSTL...TWO AREAS OF THUNDERSTORMS ARE EXPECTED TO
AFFECT KSTL OVER THE NEXT 6 HOURS. THE FIRST AREA WILL BE WITHIN
THE 10 MILE VICINITY OF THE AIRPORT OVER THE NEXT HOUR OR SO. THE
SECOND AREA OF THUNDERSTORMS EXTENDED BETWEEN KCOU AND KUIN AT TAF
ISSUANCE AND THIS LINE IS EXPECTED TO REACH KSTL AROUND 20Z. THERE
IS A GREAT DEAL OF UNCERTAINTY REGARDING CONVECTIVE TRENDS FOR
LATE TONIGHT AND TOMORROW AFTN BECAUSE WHAT HAPPENS LATER WILL
DEPEND ON WHAT HAPPENS ACROSS THE REGION THIS AFTN. SWLY WINDS
WILL BECOME NWLY AFTER THE LINE OF THUNDERSTORMS MOVES THROUGH
THEN BECOME SLY AGAIN TONIGHT. STRONGER WINDS SHOULD MIX DOWN TO
THE SURFACE TOMORROW AND PRODUCE WIND GUSTS OF 20-25 KTS.
KANOFSKY
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
1057 AM CDT MON MAY 27 2013
.MESOSCALE DISCUSSION...
ISSUED AT 1034 AM CDT MON MAY 27 2013
THE SETUP FOR THE REMAINDER OF TODAY REMAINS RATHER COMPLEX. FIRST
OFF...WE CONTINUE TO MONITOR AN MCS ALONG AND IMMEDIATELY SOUTH OF
THE INTERSTATE 70 CORRIDOR. WHILE THE LOW LEVEL JET HAS STARTED TO
WEAKEN...THE KSGF VAD WIND PROFILE CONTINUES TO INDICATE AROUND 40
KNOTS OF MAGNITUDE. THE LATEST RAP RUN HAS FINALLY CAUGHT ONTO
THIS SLOWER DEMISE TO THE LOW LEVEL JET. WE ARE THEREFORE
EXPECTING THE MCS TO CONTINUE ITS SOUTHEASTWARD DRIFT INTO
CENTRAL MISSOURI FOR THE NEXT FEW HOURS UNTIL THE JET FINALLY
WEAKENS.
ONCE WE GET INTO EARLY THIS AFTERNOON...WE WILL THEN BE LOOKING AT
MORE IN THE WAY OF SURFACE BASED CONVECTION POTENTIAL.
MODIFICATION OF THE 12 UTC KSGF RAOB ALONG WITH SHORT RANGE
FORECAST SOUNDINGS INDICATES THERE WILL BE LITTLE IN THE WAY OF A
CAPPING INVERSION THIS AFTERNOON. MLCAPE VALUES WILL BE IN THE
2000 TO 3000 J/KG RANGE. THUS...OUTFLOW FROM THE MCS MAY CONTINUE
TO KICK UP ADDITIONAL UPDRAFTS. ADDITIONALLY...SATELLITE IMAGERY
INDICATES SOME SORT OF MID LEVEL WEAKNESS DRIFTING EAST ALONG THE
KANSAS/OKLAHOMA STATE LINE. THIS FEATURE MAY ALSO SERVE AS A FOCUS
FOR CONVECTION THIS AFTERNOON.
WITH ALL OF THAT SAID...WE HAVE RAISED POPS OVER MOST AREAS FROM
17 UTC THROUGH SUNSET. THE HIGHEST POPS WERE PLACED ACROSS THE
TRUMAN AND LAKE OF THE OZARKS REGION TO COVER THE MCS. THE MAIN
THREATS FROM ANY STORMS WILL BE FREQUENT LIGHTNING AND LOCALLY
TORRENTIAL RAINFALL. ONCE STORMS BECOME SURFACE BASED...WE WILL
HAVE TO WATCH FOR ANY EASTWARD MOVING LINE SEGMENTS FOR GUSTY WIND
POTENTIAL GIVEN THE ORIENTATION OF LOW LEVEL SHEAR VECTORS.
&&
.UPDATE...
ISSUED AT 539 AM CDT MON MAY 27 2013
QUICK UPDATE TO MORNING FORECAST JUST SENT TO UPDATE POPS OVER
CENTRAL MISSOURI BASED ON LATEST RADAR TRENDS. MCS CONTINUES TO
DIVE SOUTH TOWARD KANSAS CITY EARLY THIS MORNING...AND SEEMS TO BE
HOLDING TOGETHER WELL FOR NOW. THE ENVIRONMENT BECOMES SOMEWHAT
MORE HOSTILE FURTHER SOUTH...AND SO CONTINUED SOUTHWARD MOVEMENT
ALONG WITH A DECREASE IN LLJ STRENGTH SHOULD RESULT IN A WEAKENING
TREND WITH TIME. NONETHELESS...AT LEAST SCATTERED THUNDERSTORMS
SEEM POSSIBLE OVER CENTRAL MISSOURI BY 9 AM OR SO...AND CHANCES
MAY PUSH A LITTLE FURTHER SOUTH TOWARD I-44 CLOSER TO MID DAY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 240 AM CDT MON MAY 27 2013
THE REMAINS OF A MCS HAVE DROPPED SOUTH INTO CENTRAL MISSOURI AS
OF 2 AM...ALBEIT IN A RAPIDLY DECAYING FASHION. THUNDERSTORMS
ASSOCIATED WITH THIS ACTIVITY CONTINUE TO PERCOLATE NORTH OF THE
U.S. 54 CORRIDOR...AND THIS TREND SHOULD CONTINUE THROUGH EARLY TO
MID MORNING. A WELL-DEFINED OUTFLOW BOUNDARY ASSOCIATED WITH THIS
ACTIVITY STRETCHES ACROSS MOST OF CENTRAL AND WEST-CENTRAL
MISSOURI...AND SOME ADDITIONAL ELEVATED ACTIVITY MAY BE POSSIBLE
BEFORE SUNRISE ALONG THE WESTERN FLANK OF THIS OUTFLOW...WHERE
THERE WILL BE AT LEAST SOME INTERSECTION WITH THE LLJ AXIS.
ANOTHER MCS IS CURRENTLY DROPPING SOUTHEAST THROUGH THE MISSOURI
RIVER VALLEY (APPROACHING OMAHA AREA AS OF 2 AM)...AND WILL CONTINUE
SOUTHEAST INTO NORTHERN MISSOURI BEFORE SUNRISE. AS WAS THE CASE
WITH THE FIRST MCS...A DIMINISHING TREND IS EXPECTED ONCE IT OUTRUNS
A MORE FAVORABLE SHEAR ENVIRONMENT AND BECOMES VERY OUTFLOW
DOMINATE. SOME OUTFLOW FROM THIS COMPLEX MAY MAKE IT INTO THE
NORTHERN SECTIONS OF THE CWA THIS MORNING AS WELL.
ADDITIONAL CONVECTION APPEARS POSSIBLE LATER TODAY OVER THE NORTHERN
CWA...TIED TO THE REMNANT OUTFLOW BOUNDARIES ACROSS CENTRAL MISSOURI.
ANYTHING THAT DEVELOPS DURING THE DAYTIME HOURS TODAY SHOULD BE
FAIRLY ISOLATED IN NATURE...AND SHOULD DISSIPATE FAIRLY QUICKLY
WITH SUNSET.
OTHERWISE...BREEZY CONDITIONS WILL CONTINUE TODAY...WITH HIGHS AGAIN
WARMING INTO THE LOW TO MID 80S. READINGS MAY BE JUST A FEW DEGREES
COOLER OVER THE NORTHEASTERN CWA WHERE CLOUD COVER AND ISOLATED
THUNDERSTORMS WILL LIMIT HEATING TO SOME DEGREE.
LATER THIS EVENING INTO TONIGHT...WIDESPREAD CONVECTION IS EXPECTED
TO DEVELOP ACROSS NORTHERN KANSAS AND SOUTHERN NEBRASKA...WITH SOME
INDICATIONS THAT ACTIVITY WILL ORGANIZE INTO A FORWARD PROPAGATING
MCS. THIS MCS SHOULD MAINLY AFFECT AREAS NORTH OF I-70 LATER
TONIGHT...THOUGH WE WILL NEED TO WATCH FOR THE POTENTIAL FOR OUTFLOW
SETTLING SOUTH WITH TIME...PERHAPS AFFECTING SOME OF OUR
SOUTHEASTERN KANSAS COUNTIES AND AREAS NORTH OF U.S. 54.
FOR NOW...DON`T THINK THE POTENTIAL IS TERRIBLY HIGH...AND WILL
JUST CARRY SLIGHTS ACROSS THIS AREA AFTER 06Z.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 240 AM CDT MON MAY 27 2013
A GRADUAL AMPLIFICATION OF THE OVERALL CONUS PATTERN WILL COMMENCE
LATER TONIGHT INTO THE DAY TUESDAY. AS THE WESTERN TROUGH
DEEPENS...SOUTHWEST FLOW ALOFT SHOULD ADVECT IN RATHER WARM MID
LEVEL TEMPS FOR TUESDAY...LITERALLY KEEPING A LID ON CONVECTION
OVER THE CWA.
BY WEDNESDAY...HEIGHT FALLS WILL COMMENCE OVER THE AREA...SUGGESTING
A GRADUAL WEAKENING IN INHIBITION WITH TIME. THUNDERSTORM POTENTIAL
WILL INCREASE WEDNESDAY EVENING AND ESPECIALLY WEDNESDAY NIGHT...AS
WIDESPREAD CONVECTION DEVELOPS ACROSS THE PLAINS AND MOVES
EAST/NORTHEAST. WE`LL NEED TO WATCH FOR A FEW STRONGER STORMS
WEDNESDAY NIGHT AS OVERALL BULK SHEAR INCREASES WITH TIME...BUT THE
PRIMARY SURFACE BOUNDARIES REMAINING WELL TO OUR WEST...THINK THAT
SEVERE WX WILL BE THE EXCEPTION.
ON THURSDAY...SEVERAL ADDITIONAL ROUNDS OF CONVECTION SHOULD FIRE TO
OUR WEST...AGAIN MOVING WITH TIME INTO THE CWA. WITH STORM
MOTION VECTORS TO THE NORTHEAST...AREAS WEST OF U.S. 65 SHOULD SEE
THE GREATEST STORM COVERAGE.
BY FRIDAY INTO SATURDAY...A COLD FRONT WILL FINALLY BEGIN TO SWEEP
SOUTHEAST ACROSS THE CENTRAL PLAINS. A LINE OF CONVECTION SHOULD
FIRE ALONG THE COLD FRONT FRIDAY...AND MOVE SLOWLY ACROSS THE CWA
WITH THE FRONT THROUGH SATURDAY. WITH SHEAR VECTORS PARALLEL TO THE
FRONTAL BOUNDARY...WIDESPREAD SEVERE WEATHER MAY BE HARD TO COME
BY. THAT SAID...1500 J/KG OF MLCAPE AHEAD OF THE FRONT WILL BE MORE
THE SUFFICIENT FOR A FEW STRONGER STORMS. PERHAPS OF GREATER CONCERN
IS A HEAVY RAIN THREAT...AS STORMS TRAIN ALONG THE SURFACE BOUNDARY
FROM SOUTHWEST TO NORTHEAST. WITH DEWPOINTS IN THE UPPER 60S TO LOW 70S
AND PWAT VALUES APPROACHING 1.75 INCHES (NEARLY 2 STANDARD
DEVIATIONS ABOVE NORMAL FOR THIS TIME OF YEAR)...RAINFALL RATES WILL
BE HEALTHY. CONSIDERING THE INITIAL ROUNDS OF CONVECTION WEDNESDAY NIGHT
AND THURSDAY...STORM TOTAL RAINFALL LOOKS TO BE SOMEWHAT HIGHER
ALONG AND NORTH OF I-44.
THE COLD FRONT SHOULD CLEAR THE AREA BY LATE SATURDAY AND SATURDAY
NIGHT...WITH HIGH PRESSURE BUILDING IN BY SUNDAY. THIS LOOKS TO
RESULT IN A PLEASANT END TO THE WEEKEND...WITH TEMPERATURES LIKELY
RIGHT AROUND OR JUST BELOW NORMAL FOR THE FIRST OF JUNE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 638 AM CDT MON MAY 27 2013
RATHER COMPLEX FORECAST OVER THE NEXT 24 HOURS. ALTOCUMULUS DECK
AROUND 5000 FT IS PRODUCING A FEW SHOWERS ACROSS CENTRAL MISSOURI
AND THE EASTERN OZARKS...AND SHOULD NOT AFFECT THE JLN/SGF/BBG
AERODROMES. A LINE OF THUNDERSTORMS MOVING SOUTHWARD ACROSS
NORTHEAST KANSAS AND NORTHWEST MISSOURI WILL LIKELY FALL APART AS
THE MORNING PROGRESSES...THOUGH LEAVE A BOUNDARY NEARBY ACROSS THE
AREA. A FEW OTHER BOUNDARIES ARE PRESENT WHICH COULD RESULT IN THE
POTENTIAL FOR WIDELY SCATTERED SHRA/TSRA THIS AFTERNOON...
ESPECIALLY ACROSS CENTRAL MISSOURI. CONFIDENCE IS JUST TOO LOW AT
THIS TIME TO INCLUDE ANY RISK FOR JLN/SGF/BBG. THIS CHANGES
TONIGHT AS A MORE ROBUST CLUSTER OF THUNDERSTORM DEVELOPS OVER
SOUTHERN NEBRASKA AND NORTHERN KANSAS AND MOVES TO THE EAST
SOUTHEAST. THIS WILL HAVE THE POTENTIAL TO CLIP THE JLN/SGF
AERODROMES. LOW LEVEL WIND SHEAR WILL ONCE AGAIN BE AN ISSUE
TONIGHT AS A SOUTHWESTERLY LOW LEVEL JET SPREADS OVER THE REGION.
OVERALL EXPECT VFR CONDITIONS WITH BRIEF BOUTS OF IFR POSSIBLE
WITH ANY THUNDERSTORM ACTIVITY.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
MESOSCALE...SCHAUMANN
UPDATE...BOXELL
SHORT TERM...BOXELL
LONG TERM...BOXELL
AVIATION...GAGAN
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
748 AM CDT MON MAY 27 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT MON MAY 27 2013
ONCE AGAIN DEALING WITH A COMPLEX FORECAST WITH THE SENSIBLE WEATHER
STRONGLY CONTROLLED BY MESOSCALE FACTORS...SOMETHING THE MODELS
TYPICALLY HAVE DIFFICULTY IN RESOLVING. THE CONVECTIVE SYSTEM
CURRENTLY EXTENDING THROUGH EASTERN MO HAS BEEN WEAKENING AND
SHRINKING OVER THE LAST FEW HOURS AS IT MOVES ESEWD TOWARDS THE MS
RIVER. I SEE NO REASON FOR THIS TREND NOT TO CONTINUE...WITH A
CONTINUED DECREASE IN INTENSITY AND COVERAGE AS IT OUTRUNS THE
INSTABILITY AND BETTER LOW LEVEL FORCING. ATTENTION THEN TURNS TO
THE MATURE BOW ECHO SYSTEM/MCS ACROSS WESTERN IOWA/SERN NEBRASKA.
THIS WELL-DEFINED SYSTEM IS BEING FEED BY A 40+KT SWLY LLJ WITH
MUCAPES OF 1500-2000 J/KG. VIRTUALLY ALL THE EXPLICIT CONVECTION
ALLOWING MODELS INCLUDING THE HRRR BRING THIS SYSTEM SEWD THIS
MORNING AND HAVE IT IMPACTING THE AREA ALONG AND NORTH OF
I-70...PRIMARILY THIS AFTERNOON. I`M NOT SURE ABOUT THE TIMING OR
THE EXACT STRUCTURE OF THE FINAL PRODUCT BUT THIS SCENARIO LOOKS
QUITE REASONABLE AND I HAVE LIKELY POPS OVER A MOST OF THE NRN
2/3RDS OF THE CWA. THE SYSTEM IS MOVING AT A PRETTY GOOD CLIP
RIGHT NOW AND PURE EXTRAPOLATION WOULD HAVE IT ENTERING THE NW
PORTION OF THE CWA 14Z OR SO...HOWEVER IT MAY BECOME MORE ELONGATED
WITH TIME. THE LONGER IT TAKES TO ENTER THE CWA...THE GREATER THE
OPPORTUNITY FOR THE AIR MASS AHEAD OF IT TO DESTABILIZE AND THEN FOR
THE SYSTEM AND ITS MESOSCALE BOUNDARY TO INTERACT WITH. IT COULD
POSE A LOCALLY HEAVY RAIN AND WIND THREAT DEPENDING ON ITS FINAL
INTENSITY.
NORTHERN PORTIONS OF MO INTO WEST CENTRAL IL LOOK ACTIVE AGAIN
TONIGHT. A SHORTWAVE WILL BE MOVING ENEWD FROM THE PLAINS INTO THE
MID/UPPER MS VALLEY PROVIDING LARGE SCALE ASCENT ALONG WITH
FORCING VIA A STOUT 50+ KT VEERING SWLY LLJ. THIS WILL PROVIDE
STRONG SUPPORT FOR AT LEAST ONE AND POSSIBLY SEVERAL MCSS WHICH
TRACK EASTWARD FROM THE CENTRAL PLAINS AND EFFECT PORTIONS OF NRN
MO. AGAIN THERE COULD BE A WIND AND HEAVY RAIN THREAT WITH ANY
SYSTEM.
GLASS
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 400 AM CDT MON MAY 27 2013
THE CHANCE OF SHOWERS AND THUNDERSTORMS LINGERS A BIT LONGER THAN
PREVIOUSLY FORECAST INTO TUESDAY AND TUESDAY NIGHT ACCOUNTING FOR
RESIDUAL BOUNDARIES FROM TONIGHTS ACTIVITY...HOWEVER OVERALL THE
AREA IMPACTED SHOULD BE SHRINKING AND TEMPERATURES WILL BE WARMING
TUESDAY AND WEDNESDAY AS A RIDGE BUILDS THRU THE ERN U.S. BY THE
LATER PART OF THE WEEK AND INTO THE WEEKEND WE GET BACK INTO AN
ACTIVE PATTERN AS A DEEP UPPER TROF SLOWLY PROGRESSES EASTWARD
INTO THE NATIONS MIDSECTION.
GLASS
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 742 AM CDT MON MAY 27 2013
DEALING WITH NEXT MCS THAT IS DROPPING SOUTH AND SOUTHEAST INTO MO
AS OF 1230Z. IN THE MEANTIME...KUIN HAS SOME LINGERING MVFR
CIGS...WHICH SHOULD LIFT TO VFR BY 16Z AS NEXT ROUND OF STORMS
MOVES IN. OTHERWISE...STORMS TO MOVE INTO KCOU BY 16Z AND METRO
AREA BY 19Z. STILL HARD TO PIN DOWN EXACT TIMING OF PCPN...SO JUST
HAVE VCTS MENTION AT THIS TIME. STORMS TO WEAKEN AND EXIT BETWEEN
21Z AND 00Z. ANOTHER ROUND OF STORMS POSSIBLE LATE TONIGHT...BUT
ONCE AGAIN TIMING AND COVERAGE HARD TO PIN DOWN...SO JUST HAVE
VCTS MENTION AFTER 07Z-10Z TUESDAY TIMEFRAME.
SPECIFICS FOR KSTL...DEALING WITH NEXT MCS THAT IS DROPPING SOUTH
AND SOUTHEAST INTO MO AS OF 1230Z. STORMS TO MOVE INTO METRO AREA
BY 19Z. STILL HARD TO PIN DOWN EXACT TIMING OF PCPN...SO JUST HAVE
VCTS MENTION AT THIS TIME. STORMS TO WEAKEN AND EXIT BY 00Z TUESDAY.
ANOTHER ROUND OF STORMS POSSIBLE LATE TONIGHT...BUT ONCE AGAIN
TIMING AND COVERAGE HARD TO PIN DOWN...SO JUST HAVE VCTS MENTION
AFTER 10Z TUESDAY.
BYRD
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
403 AM CDT MON MAY 27 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT MON MAY 27 2013
ONCE AGAIN DEALING WITH A COMPLEX FORECAST WITH THE SENSIBLE WEATHER
STRONGLY CONTROLLED BY MESOSCALE FACTORS...SOMETHING THE MODELS
TYPICALLY HAVE DIFFICULTY IN RESOLVING. THE CONVECTIVE SYSTEM
CURRENTLY EXTENDING THROUGH EASTERN MO HAS BEEN WEAKENING AND
SHRINKING OVER THE LAST FEW HOURS AS IT MOVES ESEWD TOWARDS THE MS
RIVER. I SEE NO REASON FOR THIS TREND NOT TO CONTINUE...WITH A
CONTINUED DECREASE IN INTENSITY AND COVERAGE AS IT OUTRUNS THE
INSTABILITY AND BETTER LOW LEVEL FORCING. ATTENTION THEN TURNS TO
THE MATURE BOW ECHO SYSTEM/MCS ACROSS WESTERN IOWA/SERN NEBRASKA.
THIS WELL-DEFINED SYSTEM IS BEING FEED BY A 40+KT SWLY LLJ WITH
MUCAPES OF 1500-2000 J/KG. VIRTUALLY ALL THE EXPLICIT CONVECTION
ALLOWING MODELS INCLUDING THE HRRR BRING THIS SYSTEM SEWD THIS
MORNING AND HAVE IT IMPACTING THE AREA ALONG AND NORTH OF
I-70...PRIMARILY THIS AFTERNOON. I`M NOT SURE ABOUT THE TIMING OR
THE EXACT STRUCTURE OF THE FINAL PRODUCT BUT THIS SCENARIO LOOKS
QUITE REASONABLE AND I HAVE LIKELY POPS OVER A MOST OF THE NRN
2/3RDS OF THE CWA. THE SYSTEM IS MOVING AT A PRETTY GOOD CLIP
RIGHT NOW AND PURE EXTRAPOLATION WOULD HAVE IT ENTERING THE NW
PORTION OF THE CWA 14Z OR SO...HOWEVER IT MAY BECOME MORE ELONGATED
WITH TIME. THE LONGER IT TAKES TO ENTER THE CWA...THE GREATER THE
OPPORTUNITY FOR THE AIR MASS AHEAD OF IT TO DESTABILIZE AND THEN FOR
THE SYSTEM AND ITS MESOSCALE BOUNDARY TO INTERACT WITH. IT COULD
POSE A LOCALLY HEAVY RAIN AND WIND THREAT DEPENDING ON ITS FINAL
INTENSITY.
NORTHERN PORTIONS OF MO INTO WEST CENTRAL IL LOOK ACTIVE AGAIN
TONIGHT. A SHORTWAVE WILL BE MOVING ENEWD FROM THE PLAINS INTO THE
MID/UPPER MS VALLEY PROVIDING LARGE SCALE ASCENT ALONG WITH
FORCING VIA A STOUT 50+ KT VEERING SWLY LLJ. THIS WILL PROVIDE
STRONG SUPPORT FOR AT LEAST ONE AND POSSIBLY SEVERAL MCSS WHICH
TRACK EASTWARD FROM THE CENTRAL PLAINS AND EFFECT PORTIONS OF NRN
MO. AGAIN THERE COULD BE A WIND AND HEAVY RAIN THREAT WITH ANY
SYSTEM.
GLASS
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 400 AM CDT MON MAY 27 2013
THE CHANCE OF SHOWERS AND THUNDERSTORMS LINGERS A BIT LONGER THAN
PREVIOUSLY FORECAST INTO TUESDAY AND TUESDAY NIGHT ACCOUNTING FOR
RESIDUAL BOUNDARIES FROM TONIGHTS ACTIVITY...HOWEVER OVERALL THE
AREA IMPACTED SHOULD BE SHRINKING AND TEMPERATURES WILL BE WARMING
TUESDAY AND WEDNESDAY AS A RIDGE BUILDS THRU THE ERN U.S. BY THE
LATER PART OF THE WEEK AND INTO THE WEEKEND WE GET BACK INTO AN
ACTIVE PATTERN AS A DEEP UPPER TROF SLOWLY PROGRESSES EASTWARD
INTO THE NATIONS MIDSECTION.
GLASS
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1135 PM CDT SUN MAY 26 2013
THUNDERSTORM TRENDS CONTINUE TO BE THE PRIMARY FOCUS FOR THIS TAF
CYCLE. CURRENT THINKING IS THAT THE CLUSTER OF STORMS OVER EAST
CENTRAL MISSOURI WILL CONTINUE MOVING SLOWLY EASTWARD. IT SHOULD
PRODUCE GUSTY WINDS UP TO 20-30KTS...AND OCCASIONAL HEAVY RAIN. A
SECOND LINE OF STORMS WILL CONTINUE MOVING SOUTH-SOUTHEAST FROM
NORTHEAST MISSOURI/WEST CENTRAL ILLINOIS DOWN TO NEAR THE MISSOURI
RIVER BY 08-09Z. IT`S UNCLEAR AT THIS TIME HOW FAR EAST THE
CLUSTER WILL STRETCH...BUT THE LOW LEVEL JET IS FORECAST TO
CONTINUE TO PUMP WARM AND UNSTABLE AIR INTO THE AREA...SO CURRENT
THINKING IS THAT MOST OF THE AREA ALONG AND WEST OF THE
MISSISSIPPI AT LEAST DOWN TO THE ST. LOUIS METRO AREA WILL SEE
SOME THUNDERSTORMS BEFORE SUNRISE. THE SECOND LINE OF STORMS WILL
ALSO PRODUCE GUSTY WINDS OF 20-30KTS FROM THE NORTH-NORTHWEST.
STILL LOOKS LIKELY THAT THE ATMOSPHERE WILL RESET MONDAY AFTERNOON
FOR ANOTHER ROUND OF AFTERNOON STORMS. TIMING AND AREAL COVERAGE
WILL BE HIGHLY DEPENDENT ON WHAT HAPPENS OVER THE NEXT 8 TO 10
HOURS WITH THE CURRENT ROUND OF STORMS.
SPECIFICS FOR KSTL...
THUNDERSTORM TRENDS CONTINUE TO BE THE PRIMARY FOCUS FOR THIS TAF
CYCLE. CURRENT THINKING IS THAT THE CLUSTER OF STORMS NORTHWEST OF
THE TERMINAL WILL CONTINUE MOVING SLOWLY EASTWARD. IT SHOULD
PRODUCE GUSTY WINDS UP TO 20-30KTS BUT THE HEAVIEST RAIN SHOULD
REMAIN NORTH OF LAMBERT. A SECOND LINE OF STORMS WILL CONTINUE MOVING
SOUTH-SOUTHEAST FROM NORTHEAST MISSOURI/WEST CENTRAL ILLINOIS
DOWN TO NEAR THE MISSOURI RIVER BY 08-09Z. IT`S UNCLEAR AT THIS
TIME HOW FAR EAST THE CLUSTER WILL STRETCH...BUT THE LOW LEVEL JET
IS FORECAST TO CONTINUE TO PUMP WARM AND UNSTABLE AIR INTO THE
AREA. CURRENT THINKING IS THAT LAMBERT WILL GET SOME THUNDERSTORMS
AND IFR OUT OF THIS SECOND WAVE. THE SECOND LINE OF STORMS WILL
ALSO PRODUCE GUSTY WINDS OF 20-30KTS FROM THE NORTH-NORTHWEST.
STILL LOOKS LIKELY THAT THE ATMOSPHERE WILL RESET MONDAY AFTERNOON
FOR ANOTHER ROUND OF AFTERNOON STORMS. TIMING AND AREAL COVERAGE
WILL BE HIGHLY DEPENDENT ON WHAT HAPPENS OVER THE NEXT 8 TO 10
HOURS WITH THE CURRENT ROUND OF STORMS.
CARNEY
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1154 PM CDT SUN MAY 26 2013
.UPDATE...
ISSUED AT 900 PM CDT SUN MAY 26 2013
THUNDERSTORMS THAT PRODUCED 2-4 INCHES NORTH OF COLUMBIA EARLIER THIS
EVENING HAVE PROGRESSED EASTWARD INTO A LINE NOW MOVING TOWARD THE ST.
LOUIS METRO. ADDITIONAL STORMS HAVE DEVELOPED IN THE LAST TWO HOURS
OVER IOWA THAT MOVING SOUTHWARD. PROPAGATION VECTORS FROM THE RAP SUGGEST
THAT THAT THIS IOWA ACTIVITY WILL MOVE SOUTH INTO THE CWA INTO THE NEXT
FEW HOURS. THE RAP HAS BEEN CONSISTENT IN SHOWING THAT LOW LEVEL MOISTURE
CONVERGENCE WILL STRENGTHEN OVER THE NORTHERN/CENTRAL CWA THROUGH 06-09Z
BEFORE IT LIFTS NORTHEAST OF THE CWA BY 12Z. WILL UP POPS TO LIKELY/
CATEGORICAL IN AREAS ALONG AND NORTH OF I-70 IN MISSOURI/I-64 IN
ILLINOIS. WHILE EFFECTIVE SHEAR REMAINS MARGINAL FOR STORM ORGANIZATION...
MUCAPES OF 1000-2000 J/KG SUGGEST THAT A FEW STRONG TO SEVER THUNDERSTORMS
ARE POSSIBLE TONIGHT. IN ADDITION....PWATS IN THE 1.5-1.8 INCH
RANGE SUGGEST THAT THERE WILL CONTINUE TO BE THE POTENTIAL FOR
SOME LOCALLY HEAVY RAINFALL TONIGHT.
BRITT
&&
.SHORT TERM...(THROUGH LATE TONIGHT)
ISSUED AT 319 PM CDT SUN MAY 26 2013
SCT AFTN THUNDERSTORMS INVOF A SFC WMFNT WILL PERSIST INTO THE EARLY
EVENING HOURS BEFORE GRADUALLY DISSIPATING WITH THE LOSS OF DAYTIME
HEATING. STRONG CONVERGENCE ALONG THE SFC WMFNT IN SERN NEB AND SWRN
IA MIGHT PRODUCE A THUNDERSTORM COMPLEX THAT PROPAGATES SEWD WITH
TIME. IF THIS COMPLEX DEVELOPS AND IF IT HOLDS TOGETHER THEN IT
MIGHT AFFECT PARTS OF THE CWA LATER TONIGHT.
KANOFSKY
.LONG TERM...(MONDAY THROUGH NEXT SUNDAY)
ISSUED AT 319 PM CDT SUN MAY 26 2013
(MONDAY-WEDNESDAY)
WITH LATEST GUIDANCE STILL VERY MURKY REGARDING CONVECTIVE TRENDS SO
WILL MAINTAIN A FAIRLY BROAD BRUSH APPROACH TO FORECAST FOR THE NEXT
48 HOURS...AND LEAVE THE FINER DETAILS TO THE SHORT TERM WHEN TRENDS
ARE A BIT MORE DEFINABLE. OVERALL...GOING FORECAST TRENDS ARE
STILL LOOKING QUITE REASONABLE SO CHANGES ARE GENERALLY MINOR.
SYNOPTICALLY...THERE ISN`T MUCH CHANGE EXPECTED THROUGH MONDAY
NIGHT...WITH DIFFUSE AND BROAD LOW LEVEL WAA PROGGED ACROSS AREA
WHILE SEVERAL WEAK SHORTWAVES DRIFT THROUGH WEAK UPPER RIDGE PARKED
ACROSS AREA. MOST OF THE 12Z RUNS DO DEPICT A MORE ACTIVE DAY ON
MONDAY THAN WHAT OCCURRED TODAY...AND THIS DOES SEEM LIKE A
REASONABLE TREND AS IT APPEARS THAT THE WEAK SHORTWAVES DO MAKE MORE
OF AN IMPACT ON THE EVER WEAKENING RIDGE. HIGHEST POPS...IN THE
LIKELY RANGE...WILL CONTINUE OVER N HALF OF THE CWA...WITH CHANCE
POPS S OF I-70.
IT STILL APPEARS THAT POPS WILL BE WINDING DOWN FROM S TO N ACROSS
THE AREA MONDAY NIGHT AND TUESDAY. SW FLOW IS FORECAST TO BECOME
ESTABISHED OVER THE REGION IN RESPONSE TO SYSTEM DIGGING INTO THE
WEST...WHICH SHOULD IN TURN CAUSE THE LOW LEVEL THERMAL
GRADIENT/ISENTROPIC LIFT THAT HAS BEEN PARKED OVER THE AREA TO SHIFT
N AND EAST OF THE REGION. THERE IS SOME CONCERN ABOUT A MEAGER
INCREASE IN DYNAMICS OVER OUR NW COUNTIES DURING THIS PATTERN SHIFT
THAT COULD ALLOW THE STORM THREAT TO LINGER A BIT LONGER...BUT THIS
IS QUITE SUBTLE SO FOR NOW WILL KEEP POPS BELOW CHANCE CATEGORY IN
THE TUE-WED TIME FRAME.
RAIN AND CONVECTIVE CLOUD DEBRIS MAY TEND TO HOLD TEMPS ON
MONDAY....HOWEVER BY MIDWEEK CWA SHOULD BE WELL INTO THE WARM
SECTOR WITH LITTLE IN THE WAYOF SIGNIFICANT CLOUDINESS. TEMPS AND
HUMIDITY LEVELS WILL BE TAKING ON A BIT OF AN EARLY SUMMER
FEEL...WITH HIGHS IN THE 85-90 DEGREE RANGE BY WEDNESDAY.
(THURSDAY-SUNDAY)
THE END OF THE WEEK AND NEXT WEEKEND MAY BE ANOTHER PERIOD OF
UNSETTLED WEATHER FOR THE CWA. SW FLOW ALOFT WILL BRING A SERIES
OF DISTURBANCES OUT OF THE WESTERN U.S...AND INTERACT WITH WHAT
SHOULD BE A WARM AND MODERATELY UNSTABLE AIRMASS. THUNDERSTORM
THREAT WILL RETURN TO THE FORECAST THURSDAY THROUGH
FRIDAY...WITH THE HIGHEST POPS SHOULD BE OVER NW HALF OF THE CWA
WHERE DYNAMICS WILL BE MOST ROBUST. HOWEVER...IT MAY BE THAT
STORMS WILL HAVE A TOUGH TIME PUSHING INTO SE MO AND S IL AS DUE
TO RIDGING OVER THE SE CONUS SUPPRESSING EWD PROGRESSION OF
DYNAMICS AND STORMS. EWD SHIFT OF UPPER TROF SHOULD MEAN SHOWERS
AND THUNDERSTORMS FOR MOST OF THE AREA NEXT WEEKEND.
TEMPERATURES SHOULD REMAIN AT OR ABOVE NORMAL FOR MUCH OF THE
MEDIUM RANGE.
TRUETT
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1135 PM CDT SUN MAY 26 2013
THUNDERSTORM TRENDS CONTINUE TO BE THE PRIMARY FOCUS FOR THIS TAF
CYCLE. CURRENT THINKING IS THAT THE CLUSTER OF STORMS OVER EAST
CENTRAL MISSOURI WILL CONTINUE MOVING SLOWLY EASTWARD. IT SHOULD
PRODUCE GUSTY WINDS UP TO 20-30KTS...AND OCCASIONAL HEAVY RAIN. A
SECOND LINE OF STORMS WILL CONTINUE MOVING SOUTH-SOUTHEAST FROM
NORTHEAST MISSOURI/WEST CENTRAL ILLINOIS DOWN TO NEAR THE MISSOURI
RIVER BY 08-09Z. IT`S UNCLEAR AT THIS TIME HOW FAR EAST THE
CLUSTER WILL STRETCH...BUT THE LOW LEVEL JET IS FORECAST TO
CONTINUE TO PUMP WARM AND UNSTABLE AIR INTO THE AREA...SO CURRENT
THINKING IS THAT MOST OF THE AREA ALONG AND WEST OF THE
MISSISSIPPI AT LEAST DOWN TO THE ST. LOUIS METRO AREA WILL SEE
SOME THUNDERSTORMS BEFORE SUNRISE. THE SECOND LINE OF STORMS WILL
ALSO PRODUCE GUSTY WINDS OF 20-30KTS FROM THE NORTH-NORTHWEST.
STILL LOOKS LIKELY THAT THE ATMOSPHERE WILL RESET MONDAY AFTERNOON
FOR ANOTHER ROUND OF AFTERNOON STORMS. TIMING AND AREAL COVERAGE
WILL BE HIGHLY DEPENDENT ON WHAT HAPPENS OVER THE NEXT 8 TO 10
HOURS WITH THE CURRENT ROUND OF STORMS.
SPECIFICS FOR KSTL...
THUNDERSTORM TRENDS CONTINUE TO BE THE PRIMARY FOCUS FOR THIS TAF
CYCLE. CURRENT THINKING IS THAT THE CLUSTER OF STORMS NORTHWEST OF
THE TERMINAL WILL CONTINUE MOVING SLOWLY EASTWARD. IT SHOULD
PRODUCE GUSTY WINDS UP TO 20-30KTS BUT THE HEAVIEST RAIN SHOULD
REMAIN NORTH OF LAMBERT. A SECOND LINE OF STORMS WILL CONTINUE MOVING
SOUTH-SOUTHEAST FROM NORTHEAST MISSOURI/WEST CENTRAL ILLINOIS
DOWN TO NEAR THE MISSOURI RIVER BY 08-09Z. IT`S UNCLEAR AT THIS
TIME HOW FAR EAST THE CLUSTER WILL STRETCH...BUT THE LOW LEVEL JET
IS FORECAST TO CONTINUE TO PUMP WARM AND UNSTABLE AIR INTO THE
AREA. CURRENT THINKING IS THAT LAMBERT WILL GET SOME THUNDERSTORMS
AND IFR OUT OF THIS SECOND WAVE. THE SECOND LINE OF STORMS WILL
ALSO PRODUCE GUSTY WINDS OF 20-30KTS FROM THE NORTH-NORTHWEST.
STILL LOOKS LIKELY THAT THE ATMOSPHERE WILL RESET MONDAY AFTERNOON
FOR ANOTHER ROUND OF AFTERNOON STORMS. TIMING AND AREAL COVERAGE
WILL BE HIGHLY DEPENDENT ON WHAT HAPPENS OVER THE NEXT 8 TO 10
HOURS WITH THE CURRENT ROUND OF STORMS.
CARNEY
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
923 PM MDT TUE MAY 28 2013
.UPDATE...
PRECIPITATION COMING NORTH ACROSS THE WYOMING BORDER TONIGHT HAS
MOVED SLOWLY AND BROKEN UP A BIT IN NORTHERN WYOMING. SO I LOWERED
POPS A BIT OVER THE NORTHERN HALF OF THE FORECAST AREA AND ALSO
SHERIDAN COUNTY. LATER TONIGHT THERE ARE A FEW MECHANISMS
PROVIDING FORCING ACROSS OUR FORECAST AREA INTO WEDNESDAY MORNING.
A VORT LOBE NOW IN SOUTHWEST WYOMING WILL SPIN TOWARD OUR AREA AND
ISENTROPIC LIFT WILL INCREASE OVER THE CENTRAL SECTIONS AS WELL.
ITS A BIT DIFFICULT TO SEE WHERE ALL THIS WILL FOCUS BY 6 AM. I
DECIDED TO NUDGE THE CATEGORICAL HIGHER POPS A BIT EAST FOR LATE
TONIGHT BASED ON NEWER RAP AND NAM DATA. LEFT A MENTION OF THUNDER
IN THE ZONES...BUT AFTER THIS EVENING IT MAY BE VERY SPOTTY. BT
&&
.SHORT TERM...VALID FOR WED AND THU...
WET WEATHER IS ON THE WAY AS THE 500-HPA TROUGH NOTED IN THE GREAT
BASIN ON AFTERNOON MOISTURE CHANNEL IMAGERY HEADS NORTHEAST DURING
THE NEXT FEW DAYS. SOME UNCERTAINTY EXISTS IN THE EVOLUTION OF THE
PRECIPITATION-MAKER BY THU AND FRI...BUT EVEN SO OUR CONFIDENCE IS
RELATIVELY HIGH IN ONE TO TWO INCHES OF RAIN FOR MUCH OF THE AREA.
TONIGHT...SCATTERED CONVECTION INDUCED BY WEAK INSTABILITY /MLCAPE
OF 250 TO PERHAPS 500 J/KG IN POCKETS/ AND PERHAPS AIDED BY A WEAK
RIPPLE OR TWO IN SOUTH-SOUTHWEST FLOW ALOFT WILL CONTINUE INTO THE
EVENING HOURS. MEANWHILE...THE STRONGER DYNAMIC FORCING ASSOCIATED
WITH THE MID- AND UPPER-LEVEL TROUGH WHICH HAS ITS AXIS IN UTAH AS
OF 21 UTC WILL MOVE INTO SOUTH CENTRAL MT BETWEEN 06 AND 12 UTC. A
NOTABLE BATCH OF 500-300 HPA Q-VECTOR CONVERGENCE DEVELOPS...WHICH
SHOULD ENABLE WIDESPREAD PRECIPITATION BY DAYBREAK. UPSTREAM RADAR
TRENDS THIS AFTERNOON ALREADY SHOW ENHANCED SHOWER DEVELOPMENT OUT
AHEAD OF THE TROUGH...AND QPF OUTPUT FROM 12 UTC MODELS IS CLOSELY
CLUSTERED IN SHOWING MOISTURE OVER SOUTH CENTRAL MT BY LATE NIGHT.
WE THUS HAD THE CONFIDENCE TO RAISE POPS TO 100 PERCENT FOR PLACES
LIKE LIVINGSTON AND BILLINGS AFTER 06 UTC...WHILE ACKNOWLEDGING IT
MIGHT TAKE UNTIL AFTER 09 UTC FOR RAIN TO BECOME ESTABLISHED. SNOW
LEVELS SHOULD LOWER TO NEAR 8000 FT MSL...WHICH WILL LIKELY RESULT
IN SEVERAL INCHES OF SNOW IN THE BEARTOOTH/ABSAROKAS. IMPACTS WILL
BE FELT IN PLACES LIKE THE BEARTOOTH PASS.
WED...FORCING IDENTIFIED BY SOLID 500-300 HPA Q-VECTOR CONVERGENCE
WILL CONTINUE OVER MUCH OF THE AREA. WIDESPREAD PRECIPITATION WILL
THUS CONTINUE...AND IN FACT WE DECIDED TO ADVERTISE POPS IN THE 90
TO 100 PERCENT RANGE IN MOST SPOTS FOR AT LEAST A PART OF THE DAY.
AN INVERTED SURFACE PRESSURE TROUGH WILL BECOME ESTABLISHED ACROSS
EASTERN MT BY AFTERNOON...WHICH WILL SWITCH THE FOCUS OF RAIN FROM
SOUTH CENTRAL TO SOUTHEASTERN MT AFTER 18 UTC. THAT WILL BE DUE TO
BOTH FORCING ALONG AND EAST OF THE TROUGH...AND A SWITCH TO A MORE
DOWNSLOPE WIND DIRECTION TO ITS WEST. IF THE 12 UTC GFS IS CORRECT
WITH ITS SIMULATION OF THE TROUGH...LIVINGSTON AND BILLINGS MAY BE
RELATIVELY DRY BY LATE AFTERNOON. WE LEFT LIKELY POPS IN PLACE FOR
THOSE AREAS BETWEEN 18 AND 00 UTC RIGHT NOW...BUT WE MIGHT REVISIT
THAT WITH LATER FORECASTS. THUNDERSTORMS ARE FAVORED MAINLY TO THE
EAST OF THE SURFACE TROUGH AS WELL...WHERE CALIBRATED THUNDERSTORM
PROBABILITIES FROM THE 09 UTC SREF ARE IN THE 30 PERCENT RANGE AND
MUCAPE FROM THE 12 UTC DETERMINISTIC GUIDANCE IS IN THE 500 TO 900
J/KG RANGE. FINALLY...WE RELIED ON 2-METER TEMPERATURES INSTEAD OF
MOS-BASED GUIDANCE TO BUILD THE HIGH TEMPERATURE FORECAST SINCE IT
LOOKS LIKE CLOUDS AND PRECIPITATION MAY KEEP MANY AREAS IN THE 50S
F.
WED NIGHT INTO THU...UNCERTAINTY GROWS WITH REGARD TO EVOLUTION OF
THE MID- AND UPPER-LEVEL TROUGH...BUT IT SEEMS LIKE FORCING MAY BE
FOCUSED MAINLY FROM ROUNDUP TO MILES CITY AND BAKER. DOWNSLOPE MAY
ACTUALLY PREVAIL SOUTH OF THAT LINE...THOUGH BOTH THE 12 UTC ECMWF
AND NAM SUGGEST THAT TROWAL-INDUCED MOISTURE MIGHT WRAP SOUTH INTO
MUCH MORE OF THE REGION THAN OUR CURRENT FORECAST IMPLIES. SCHULTZ
.LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE...
MODELS HAVE DIVERGED A BIT AGAIN FOR FRIDAY AS THE GFS HAS TAKEN
A BIT OF A SOUTHERN JOG WITH THE POSITION OF THE UPPER LOW. THIS
BUCKS THE TREND IT HAD BEEN SHOWING LATELY AS IT WAS TRENDING
NORTHWARD WITH THE ECMWF. ACTUALLY PREFER THE SOUTHERN SOLUTION
AND THE REASON WAS OVER THE NORTHEAST PACIFIC. STRONG ENERGY WAS
RACING AROUND THE UPPER LOW UP THERE AND THIS SHOULD MOVE
SOUTHEAST TOWARD THE GREAT BASIN. ATMOSPHERIC WEAKNESS ALREADY
EXISTS OVER THE GREAT BASIN WITH EXISTENCE OF THE CURRENT UPPER
TROUGH AND THIS WILL ALLOW THE ENERGY TO DROP INTO THIS SAME
REGION WITH LITTLE RESISTANCE. THIS WOULD LOWER HEIGHTS OVER
WYOMING AND MONTANA AND PROMPT A FARTHER SOUTH FORMATION OF THE
LOW CUTTING OFF THURSDAY AND THURSDAY NIGHT. THIS IS WHAT THE GFS
HAS AND THIS MAKES TOTAL SENSE TO ME. THEREFORE...WILL SIDE WITH
THE GFS FOR THIS PACKAGE.
THE CUT OFF UPPER LOW WILL DROP SOUTHEAST INTO WESTERN SOUTH
DAKOTA ON FRIDAY. THIS WILL WRAP PRECIPITATION BACK INTO THE AREA.
THE ECMWF WAS QUITE A BIT FARTHER NORTH WITH THE LOW AND THUS MUCH
LIGHTER WITH THE PRECIPITATION. RAISED POPS FOR FRIDAY SINCE AM
LEANING TOWARD THE GFS. ALSO LOWERED HIGHS WITH EXTENSIVE RAIN AND
CLOUDS. THE SYSTEM SHOULD FINALLY PUSH EAST FRIDAY NIGHT AND
SATURDAY TO BE FOLLOWED BY AN AMPLIFIED RIDGE FOR DRYER WEATHER
AND WARMER TEMPERATURES OVER THE WEEKEND. A NORTHERN TROUGH WILL
CRUISE ACROSS SOUTHERN CANADA SUNDAY AND MONDAY. STRONG ENERGY
WILL DIG DOWN THE BACK SIDE OF THIS LOW AND DROP INTO WESTERN
MONTANA. ENERGY AND MOISTURE WILL INCREASE DURING THIS PROCESS.
RAISED POPS MONDAY THROUGH TUESDAY. TWH
&&
.AVIATION...
A FEW THUNDERSTORMS REMAIN POSSIBLE ACROSS CENTRAL AND EASTERN
ROUTES FOR THE NEXT FEW HOURS. SHOWERS WILL BECOME WIDESPREAD
OVERNIGHT WITH LOCALLY HEAVY RAIN BY MORNING. CONDITIONS WILL
BECOME IFR IN THE HEAVIER SHOWERS BUT MOST LOCATIONS WILL HAVE
CONDITIONS LOWER TO MVFR. MOUNTAINS WILL BECOME OBSCURED AS SNOW
DEVELOPS ABOVE 8500 FEET. PRECIPITATION WILL LINGER THROUGH THE
DAY WEDNESDAY. STC
&&
.PRELIMINARY POINT TEMP/POPS...
WED THU FRI SAT SUN MON TUE
-----------------------------------------------------------
BIL 051/055 048/066 048/059 046/069 052/077 054/076 052/066
8+/T 53/T 36/W 62/T 21/B 12/T 33/T
LVM 045/052 041/064 042/057 042/071 045/076 048/075 048/065
5+/T 53/T 36/W 52/T 22/T 23/T 34/T
HDN 052/058 049/067 045/058 046/070 048/078 049/079 049/069
99/T 63/T 36/W 63/T 21/B 12/T 33/T
MLS 056/063 052/064 050/057 048/069 050/075 054/077 053/067
6+/T 85/T 56/W 64/T 22/T 23/T 33/T
4BQ 051/062 048/063 047/059 046/066 047/074 050/079 051/067
5+/T 64/T 46/W 64/T 21/U 12/T 33/T
BHK 052/064 051/063 048/057 045/064 046/070 049/076 050/067
4+/T 96/T 56/W 64/T 21/U 22/T 33/T
SHR 049/055 045/064 044/058 044/066 046/075 048/078 049/066
67/T 53/T 36/W 53/T 20/U 02/T 33/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
659 PM CDT TUE MAY 28 2013
.AVIATION...
00Z TAFS FOR KOFK...KOMA AND KLNK.
VFR CONDITIONS WILL PREVAIL THRU MOST OF THIS EVENING. AROUND
MIDNIGHT THEN...DETERIORATING CONDITIONS SHOULD BE UNDERWAY OVER
ERN NEB IN RESPONSE TO A SLOW LIFTING WARM FRONT. AS THE BNDRY
SHIFTS NORTH...EXPECT AN INCREASE IN AREAL COVERAGE OF +TSRA THRU
12Z WED MORNING. AFT 12Z...TSRA ACTIVITY SHOULD BE COMING TO A
CLOSE. BECAUSE OF INFLUX OF LLVL MOISTURE THOUGH...MVFR/IFR CIGS
WILL LIKELY PREVAIL AT ALL TAF SITES UNTIL LATE WED MORNING. VFR
THEN THE REST OF THE FCST PD.
DEE
&&
.PREV DISCUSSION... /ISSUED 249 PM CDT TUE MAY 28 2013/
DISCUSSION...
CONVECTION/POSSIBLE FLOODING THROUGH THURSDAY REMAINS PRIMARY
CONCERN.
SUBJECTIVELY PLACED QUASI-STATIONARY FRONT EXTENDED FROM FAR SERN
NEBR INTO SWRN IA AT 19Z WITH CU FIELD THICKENING NEAR/SOUTH OF
IT...ALTHOUGH VIEW SOMEWHAT HINDERED BY HIGHER CLOUDS. ALTHOUGH
FIRST AREA OF CONVECTION WAS DEVELOPING SE OF THE REGION...AND
LEADS SOME SMALL DOUBTS TO WHAT MAY HAPPEN FARTHER NW...VARIOUS
MODEL QPF INCLUDING RAP/HRRR AND 4KM WRF DVLP PRECIP OVER SERN
ZONES THROUGH EARLY EVENING. THIS LOOKS REASONABLE GIVE LATEST SPC
RUC MESO ANALYSIS PAGE SHOWED SRN ZONES ON EDGE OF ML CAPE AXIS OF
3000-4000 J/KG WITH WEAKENED/NO CAP. LOW LEVEL/DEEPER SHEAR
FAVORABLE FOR SEVERE WEATHER...SEE LATEST WATCH/MCD FOR INFO ON
THIS. SINCE SRN ZONES RECEIVED 1-2+ INCHES OF RAIN LAST EVENING...
RIVERS/STREAMS ARE RUNNING HIGH OR CLOSE TO FLOODING IN SOME
CASES. WITH FFG VALUES UNDER 2 INCHES...OPTED TO ISSUE A FLASH
FLOOD WATCH SERN COUNTIES THROUGH TONIGHT. EXTENDED WATCH TO NEBR
CITY/4 SW IA COUNTIES IN CASE STRENGTHENING LOW LEVEL JET ALLOWS
ACTIVITY TO SPREAD/DEVELOP N LATER THIS EVENING...BUT IT WAS NOTED
THAT 4KM WRF AND HRRR DROPPED CONVECTION SE THRU EARLY EVENING.
OTHERWISE ADJUSTED POPS NRN ZONES TONIGHT TO REFLECT BETTER
CHANCES LATER TONIGHT AS LOW LEVEL JET STRENGTHENS N ACROSS THE
AREA CLOSER TO AND AFTER 06Z.
DIURNALLY DECREASED POPS THRU MIDDAY WEDNESDAY BEFORE STRONGER
UPPER TROUGH BEGINS CRASHING UPPER HGTS INTO CNTRL NEBR. THIS
COULD ALLOW A LITTLE EARLIER CONVECTIVE DEVELOPMENT...IF IT EVEN
DECREASES...AND COULD ALSO SET THE STAGE FOR A SEVERE WEATHER AND
HEAVY RAIN THREAT OVER A LARGER PART OF THE FORECAST AREA. WITH
TRAINING POSSIBLE AS UPPER FLOW BECOMES MORE PARALLEL TO MEAN
SHEAR VECTORS THRU WED EVENING...TRAINING OF ECHOES COULD ADD TO
FLOODING POTENTIAL. THIS MAY NECESSITATE A FLASH FLOOD WATCH OVER
A LARGER PART OF THE AREA FOR LATE WED/WED NIGHT IN LATER
FORECASTS...BUT FOR NOW FIRST FLASH FLOOD WATCH WILL ADDRESS
SHORTER TERM FLOODING THREAT.
ACTIVE WEATHER COULD PERSIST INTO THURSDAY AS JET WRAPS ACROSS
SRN ZONES ON SOUTH END OF CLOSING UPPER LOW. QUESTION WILL THEN
SHIFT TO AMOUNT OF RESIDUAL MOISTURE THAT WILL REMAIN OVER AREA AS
UPPER TEMPS COOL BUT SURFACE WINDS TAKE ON A MORE WRLY...
DOWNSLOPE...COMPONENT. FOR NOW MADE LITTLE/NO CHANGES TO PREVIOUS
FORECAST POPS...WHICH WERE FAIRLY HIGH YET THROUGH THU
EVENING...BUT LOWERED LATE THU NGT. NO CHANGES MADE TO MODEST POPS
FRIDAY OR REST OF MODEL/PRIOR FORECAST BLEND REST OF FORECAST.
SOME POTENTIAL FOR TEMPERATURES TO REALLY WARM TOMORROW AS SRLY
WINDS INCREASE AHEAD OF TROUGH AND WITH WRLY COMPONENT TO SURFACE
WINDS ON THURSDAY. HOWEVER...WITH RISK/UNCERTAINTY OF RESIDUAL
CLOUDS AND OR TSTMS...OPTED FOR LITTLE CHANGE FROM PREVIOUS
FORECAST WHICH WAS FAIRLY ALIGNED WITH GUIDANCE.
CHERMOK
&&
HYDROLOGY...UPDATED AT 110 PM CDT...
FOR INFO ON FLASH FLOOD WATCH SEE ABOVE. OTHERWISE FLOOD WARNING
CONTINUES FOR TURKEY CREEK AT WILBER. THOUGH IT HAS CRESTED AND
STARTED FALLING FOR NOW...IT IS FORECAST TO RISE AGAIN LATER
TONIGHT AND WEDNESDAY. THE LITTLE AND BIG NEMAHA RIVERS IN
SOUTHEAST NEBRASKA DID RISE TO JUST BELOW FLOOD STAGE BUT HAVE
SINCE STARTED TO DECLINE. WARNINGS ALSO CONTINUE FOR THE MISSOURI
RIVER FROM PLATTSMOUTH DOWNSTREAM TO RULO FOR SIGNIFICANT RISES
OVER THE NEXT FEW DAYS. OMAHA ON THE MISSOURI RIVER IS FORECAST TO
RISE...BUT REMAIN JUST BELOW FLOOD LEVELS BUT WILL EVENTUALLY NEED
A FLOOD ADVISORY. THE NISHNABOTNA RIVER BASIN DID ALSO SEE
SIGNIFICANT IN BANK RISES...BUT REMAINED BELOW FLOOD STAGE AND
HAVE STARTED TO FALL. A FLOOD WARNING WAS ISSUED ON THE LITTLE
SIOUX RIVER NEAR TURIN AS IT IS FORECAST TO GO ABOUT TWO FEET
ABOVE FLOOD STAGE BY FRIDAY.
MEYER
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR NEZ068-089>093.
IA...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR IAZ079-080-090-
091.
&&
$$
99/99
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
638 AM CDT MON MAY 27 2013
.AVIATION...12Z TAFS FOR KOFK...KLNK AND KOMA.
SCATTERED SHOWERS AND THUNDERSTORMS WILL AFFECT KLNK AND KOMA
THROUGH ABOUT 17Z THIS MORNING WITH ATTENDANT MVFR CIGS/VSBYS.
SOME AREAS OF IFR CIGS NEAR KOFK SHOULD LIFT TO VFR BY 18Z. THEN
MORE THUNDERSTORMS ARE LIKELY DURING THE LATE AFTERNOON AND
EVENING...MOSTLY LIKELY DEVELOPING IN SOUTH CENTRAL NEBRASKA AND
EXPANDING EAST WITH TIME. SOME STRONG THUNDERSTORMS ARE POSSIBLE
BETWEEN 00Z AND 06Z AT ALL TAF SITES. STORMS SHOULD PERSIST PAST
06Z...WITH A GRADUAL DECREASE IN INTENSITY AND COVERAGE LATE IN
THE TAF PERIOD. THERE IS SOME INDICATION IFR CIGS WILL DEVELOP
AFTER STORMS END BETWEEN 06Z AND 12Z...BUT WILL ADDRESS THIS
SCENARIO WITH LATER TAF ISSUANCES.
DERGAN
&&
.PREV DISCUSSION... /ISSUED 425 AM CDT MON MAY 27 2013/
DISCUSSION...
VERY SHORT TERM CONCERNS WILL BE SEVERE THUNDERSTORM WATCH THAT
CONTINUES UNTIL 5AM FOR PARTS OF SOUTHERN NEBRASKA AND SOUTHWEST
IOWA. THEN...FORECAST CONCERNS CONTINUE TO BE THUNDERSTORMS AND
SEVERE WEATHER POTENTIONAL/HEAVY RAIN IN ACTIVE WEATHER PATTERN
THIS WEEK.
THE 00Z OAX SOUNDING HAD CAPE OF NEARLY 4000J/KG...STEEP MID LEVEL
SHEAR...PRECIPITABLE WATER OF 1.52 INCHES (185%)...FREEZING LEVEL OF
13,500...AND SFC-2KM SRH OF 258M2/S2. THE SURFACE WARM FRONT WAS
SOUTH OF COLUMBUS TO PLATTSMOUTH INTO SOUTHWEST IOWA. AT
00Z...THUNDERSTORMS FORMED IN SOUTHWEST IOWA ALONG THE WARM
FRONT/OUTFLOW BOUNDARY AND BY 02Z...THUNDERSTORMS HAD DEVELOPED OVER
NORTH CENTRAL NEBRASKA AND WERE SPREADING SOUTHEAST ACROSS THE
FORECAST AREA AT 06Z. THE STRONGER WINDS ALOFT WERE HAVING A TOUGH
TIME MAKING IT DOWN TO THE SURFACE...HOWEVER THE STRONGER WINDS DID
START TO REACH THE GROUND AS THE STORMS APPROACHED THE FREMONT AREA
AND AS THEY MOVED THROUGH PARTS OF DOUGLAS CO. FREMONT HAD A WIND
REPORT OF 77 MPH AND WEST OF EPPLEY 67 MPH...WITH SOME WINDS 50 TO
55 MPH.
THE 00Z H5 PATTERN HAD A TROF OVER THE WESTERN U.S. +10C AIR AT
H7 HAD SPREAD INTO SOUTH CNTRL NEB AND +9 AT OAX. THE H85 DEWPOINT
WAS 17DEG C AT KOAX.
THROUGH 06Z MONDAY NIGHT...PRECIPITABLE WATER REMAINS HIGHS...FROM
AROUND 1.5 TO 1.6 INCHES...THEN RETURNS NORTHWARD BY 00Z TUESDAY
EVENING AND REMAINS HIGH THROUGH WEDNESDAY NIGHT. THE UPPER LEVEL
JET AND H5 PATTERN WILL REMAIN FAVORABLE FOR THUNDERSTORMS TO
DEVELOP OVER THE FORECAST AREA.
TODAY...THE SURFACE BOUNDARY WILL BE AFFECTED BY THE CONVECTION
THIS MORNING AND WILL MAINTAIN SOME THUNDERSTORMS OVER PARTS OF
THE AREA UNTIL THE LOW LEVEL JET WEAKENS. THE OVERALL TREND IS A
DIURNAL WEAKENING THIS MORNING...HOWEVER LOW LEVEL FLOW RETURN
THIS AFTERNOON AND EVEN MORESO OVERNIGHT AS A 50KT LOW LEVEL JET
DEVELOPS ACROSS KANSAS AND SHORTWAVE TROF ENERGY ONCE AGAIN MOVES
ACROSS THE REGION. WITH THE FRONTAL LOCATION UNCERTAIN...TRENDED
COOLER WITH THE TEMPERATURES IN THE NORTH AND LEFT HIGHS IN THE
80S SOUTH. THIS PATTERN CONTINUES THROUGH THE WEEK AND THE UPPER
LEVEL TROF SHIFTS EASTWARD INTO THE PLAINS WEDNESDAY. WE ARE STILL
IN THE SEVERE WEATHER OUTLOOK FOR DAYS 1 THRU 3 AND HEAVY RAIN
WILL BE POSSIBLE WITH THE STORMS THAT DEVELOP. ALTHOUGH WE ARE NOT
IN THE EXCESSIVE OUTLOOK. WILL NEED TO ASSESS HEAVY RAIN POTENTIAL
AND FLASH FLOOD WATCH EACH SHIFT DUE TO THE REPEATED RAINS
EXPECTED.
AVIATION...
06Z TAFS FOR KOMA...KLNK...KOFK.
TSRA SHOULD CONTINUE IN THE KOFK AREA THE NEXT SEVERAL HOURS...
WITH THE STRONGEST ACTIVITY LIKELY BEFORE 07Z. THERE IS STILL
SOME UNCERTAINTY HOW FAR SOUTHEAST STORMS WILL REACH OVERNIGHT...
BUT HRRR MODEL DEVELOPS ACTIVITY TOWARD NORTHEAST KANSAS AND
NORTHWEST MISSOURI BY A LITTLE AFTER SUNRISE.
EXPECT A GRADUAL DECREASE IN CEILINGS THROUGH 14Z...THEN A GRADUAL
UPWARD TREND TOWARD VFR CONDITIONS AT ALL THREE SITES BY EARLY
AFTERNOON MONDAY.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
425 AM CDT MON MAY 27 2013
.DISCUSSION...
VERY SHORT TERM CONCERNS WILL BE SEVERE THUNDERSTORM WATCH THAT
CONTINUES UNTIL 5AM FOR PARTS OF SOUTHERN NEBRASKA AND SOUTHWEST
IOWA. THEN...FORECAST CONCERNS CONTINUE TO BE THUNDERSTORMS AND
SEVERE WEATHER POTENTIONAL/HEAVY RAIN IN ACTIVE WEATHER PATTERN
THIS WEEK.
THE 00Z OAX SOUNDING HAD CAPE OF NEARLY 4000J/KG...STEEP MID LEVEL
SHEAR...PRECIPITABLE WATER OF 1.52 INCHES (185%)...FREEZING LEVEL OF
13,500...AND SFC-2KM SRH OF 258M2/S2. THE SURFACE WARM FRONT WAS
SOUTH OF COLUMBUS TO PLATTSMOUTH INTO SOUTHWEST IOWA. AT
00Z...THUNDERSTORMS FORMED IN SOUTHWEST IOWA ALONG THE WARM
FRONT/OUTFLOW BOUNDARY AND BY 02Z...THUNDERSTORMS HAD DEVELOPED OVER
NORTH CENTRAL NEBRASKA AND WERE SPREADING SOUTHEAST ACROSS THE
FORECAST AREA AT 06Z. THE STRONGER WINDS ALOFT WERE HAVING A TOUGH
TIME MAKING IT DOWN TO THE SURFACE...HOWEVER THE STRONGER WINDS DID
START TO REACH THE GROUND AS THE STORMS APPROACHED THE FREMONT AREA
AND AS THEY MOVED THROUGH PARTS OF DOUGLAS CO. FREMONT HAD A WIND
REPORT OF 77 MPH AND WEST OF EPPLEY 67 MPH...WITH SOME WINDS 50 TO
55 MPH.
THE 00Z H5 PATTERN HAD A TROF OVER THE WESTERN U.S. +10C AIR AT
H7 HAD SPREAD INTO SOUTH CNTRL NEB AND +9 AT OAX. THE H85 DEWPOINT
WAS 17DEG C AT KOAX.
THROUGH 06Z MONDAY NIGHT...PRECIPITABLE WATER REMAINS HIGHS...FROM
AROUND 1.5 TO 1.6 INCHES...THEN RETURNS NORTHWARD BY 00Z TUESDAY
EVENING AND REMAINS HIGH THROUGH WEDNESDAY NIGHT. THE UPPER LEVEL
JET AND H5 PATTERN WILL REMAIN FAVORABLE FOR THUNDERSTORMS TO
DEVELOP OVER THE FORECAST AREA.
TODAY...THE SURFACE BOUNDARY WILL BE AFFECTED BY THE CONVECTION
THIS MORNING AND WILL MAINTAIN SOME THUNDERSTORMS OVER PARTS OF
THE AREA UNTIL THE LOW LEVEL JET WEAKENS. THE OVERALL TREND IS A
DIURNAL WEAKENING THIS MORNING...HOWEVER LOW LEVEL FLOW RETURN
THIS AFTERNOON AND EVEN MORESO OVERNIGHT AS A 50KT LOW LEVEL JET
DEVELOPS ACROSS KANSAS AND SHORTWAVE TROF ENERGY ONCE AGAIN MOVES
ACROSS THE REGION. WITH THE FRONTAL LOCATION UNCERTAIN...TRENDED
COOLER WITH THE TEMPERATURES IN THE NORTH AND LEFT HIGHS IN THE
80S SOUTH. THIS PATTERN CONTINUES THROUGH THE WEEK AND THE UPPER
LEVEL TROF SHIFTS EASTWARD INTO THE PLAINS WEDNESDAY. WE ARE STILL
IN THE SEVERE WEATHER OUTLOOK FOR DAYS 1 THRU 3 AND HEAVY RAIN
WILL BE POSSIBLE WITH THE STORMS THAT DEVELOP. ALTHOUGH WE ARE NOT
IN THE EXCESSIVE OUTLOOK. WILL NEED TO ASSESS HEAVY RAIN POTENTIAL
AND FLASH FLOOD WATCH EACH SHIFT DUE TO THE REPEATED RAINS
EXPECTED.
&&
.AVIATION...
06Z TAFS FOR KOMA...KLNK...KOFK.
TSRA SHOULD CONTINUE IN THE KOFK AREA THE NEXT SEVERAL HOURS...
WITH THE STRONGEST ACTIVITY LIKELY BEFORE 07Z. THERE IS STILL
SOME UNCERTAINTY HOW FAR SOUTHEAST STORMS WILL REACH OVERNIGHT...
BUT HRRR MODEL DEVELOPS ACTIVITY TOWARD NORTHEAST KANSAS AND
NORTHWEST MISSOURI BY A LITTLE AFTER SUNRISE.
EXPECT A GRADUAL DECREASE IN CEILINGS THROUGH 14Z...THEN A GRADUAL
UPWARD TREND TOWARD VFR CONDITIONS AT ALL THREE SITES BY EARLY
AFTERNOON MONDAY.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
ZAPOTOCNY
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1229 AM CDT MON MAY 27 2013
.SYNOPSIS...
ISSUED AT 315 PM CDT SUN MAY 26 2013
A DEEP UPPER LEVEL LOW...CURRENTLY ACROSS THE NORTH PACIFIC...WILL
MIGRATE SLOWLY EAST THROUGH THE PACIFIC NORTHWEST AND INTO THE NRN
PLAINS THIS WEEK. A STRONG PACIFIC COLD FRONT WILL MOVE THROUGH
THE FCST AREA WEDNESDAY NIGHT OR THURSDAY. SEVERE WEATHER IS
POSSIBLE TODAY THROUGH WEDNESDAY AS LOW PRESSURE REMAINS QUASI
STATIONARY ACROSS ERN COLORADO AND FOCUSES...MOSITURE...WARM AIR
ADVECTION AND DRY.
&&
.UPDATE...
ISSUED AT 1114 PM CDT SUN MAY 26 2013
UPDATED FORECAST TO DROP TORNADO WATCH AND ISSUE SEVERE
THUNDERSTORM WATCH.
UPDATE ISSUED AT 743 PM CDT SUN MAY 26 2013
UPDATED FORECAST TO INCLUDE TORNADO WATCH FOR NORTH CENTRAL NEBRASKA.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 315 PM CDT SUN MAY 26 2013
TONIGHT AND MONDAY...CONVECTION LATE THIS AFTERNOON INTO THE
EVENING TONIGHT...THEN LOW CLOUDS FOG DEVELOPMENT TOWARD MORNING
REMAIN FORECAST ISSUES FOR THE SHORT TERM. WEAK COLD FRONT
ANALYZED FROM SOUTHWEST NEBRASKA SOUTHWARD INTO NW KS AND ERN CO.
WARM FRONT EXTENDS FROM SW INTO SC NEBRASKA WITH INVERTED TROUGH
NORTHWARD INTO SD. NUMEROUS OUTFLOW BOUNDARIES SHOW IN THE HAND
ANALYSIS AS WELL.
QUITE A VARIED RANGE OF SHORT TERM MODEL SOLUTIONS FOR THIS EVENING
AS HRRR AND HIRES ARW SUGGEST NOTHING ORGANIZED WILL DEVELOP SOUTH
OF I80 CORRIDOR...BUT DEVELOP A MCS ACROSS THE SANDHILLS IN THE
HIGHWAY 2 VCNTY AND MOVE IT EASTWARD OVERNIGHT. THE NAM /AND HIRES
NMM/ AS WELL AS GFS SUGGEST TWO AREAS OF DEVELOPMENT...THE FIRST IN
SIMILAR AREAS TO THE PREVIOUSLY MENTIONED MODELS /SANDHILLS/ AND A
SECOND IN THE VCNTY OF THE WARM FRONT WHICH ORGANIZES INTO A MCS AND
MOVES SOUTHEAST. FCST WILL GO WITH THE IDEA THAT TO SOME DEGREE BOTH
GROUPS OF SOLUTIONS HAVE REALISTIC POSSIBILITIES BASED ON BETTER DEEP
LAYER SHEAR ACROSS THE NORTH WHICH SHOULD ALLOW FOR A BETTER
ORGANIZATION ONCE DEVELOPMENT OCCURS IN THE SANDHILLS BY EVENING.
LOW LEVEL LAPSE RATES IN THIS AREA HOWEVER ARE NOT THE BEST AS WOULD
BE EXPECTED NORTH OF THE WARM FRONT...AND ALSO BELIEVE AIR MASS IS
STILL SOMEWHAT INFLUENCED IN THE LOW LAYERS AS A RESULT OF THE
OUTFLOW THAT WAS EVIDENT EARLIER THIS MORNING. LARGE HAIL STILL A
POSSIBILITY HERE THOUGH WITH VERY STEEP MID LEVEL LAPSE RATES...EVEN
IF STORMS ARE ELEVATED WHICH SEEMS LIKELY IN THIS AREA.
FURTHER SOUTH...LOW LEVEL LAPSE RATES ARE STEEPEST ACROSS ERN CO AND
NW KS AND HAVE SURGED EWD AHEAD OF LEE SFC LOW IN NW KS. GOOD
THETA-E ADVECTION NORTHEAST OF THIS AREA SHOULD ALLOW DEVELOPMENT IN
THIS AREAS AS WELL...THOUGH COVERAGE REMAINS IN QUESTION. SPC
MESOANALYSIS INDICATES SOME CAP STILL PRESENT HERE AND SINCE LARGE
SCALE FORCING IS BEST FURTHER NORTH THE EXTENT OF CAP EROSION IS
ALSO IN QUESTION. WOULD LIKE TO SEE BETTER SFC CONVERGENCE IN THESE
LOCATIONS TO BE MORE CERTAIN ABOUT INITIATION. IF SFC BASED
DEVELOPMENT DOES OCCUR SVR POTENTIAL WILL BE HIGH AS VERY GOOD ML
CAPE IS IN PLACE. THEREFORE...FCST INCLUDES POPS IN THESE AREAS BASED ON
PREVIOUS THINKING.
THE LAST FEW NIGHTS HAS SEEN A TENDENCY TO DEVELOP LOW CLOUD BEHIND
OUTFLOW BOUNDARIES TWD DAYBREAK AND BELIEVE THAT SHOULD BE THE CASE
ONCE AGAIN MONDAY MORNING. DEPICTING LOCATIONS IS DIFFICULT BUT
FAVORED AREAS EAST OF HIGHWAY 61 SEEM MOST LIKELY AND HAVE TRENDED
THE FCST THAT WAY. EVENTUAL HIGH TEMPS WILL BE HIGHLY DEPENDENT ON
THESE LOW CLOUD DEVELOPMENT AS WELL...BUT AS WITH THE LAST FEW DAYS
AFTERNOON MIXING SHOULD ALLOW 80S MOST PLACES.
CONVECTION AGAIN POSSIBLE MONDAY AFTERNOON. MODELS SUGGESTING UPPER
TROUGH WILL CONTINUE TO MOVE EASTWARD AND SHOULD ALLOW FOR A MORE
SOUTHERN LOCATION OF SFC FEATURES ONCE CONVECTIVE DEBRIS GIVES WAY.
SOMEWHAT BETTER UPPER PV ANOMALY LOOKS TO SWING OUT ONTO THE PLAINS
BY LATE AFTERNOON MONDAY.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 315 PM CDT SUN MAY 26 2013
SFC LOW PRESSURE WILL REMAIN TUCKED ACROSS ERN COLO FOCUSING
MOISTURE...DRY AIR AND WARM AIR ADVECTION ACROSS WRN AND NCNTL NEB.
THE SFC LOW WILL GRADUALLY DEEPEN TO AROUND 992 MB BY TUESDAY AND
CONTINUING NEAR 992 MB THROUGH WEDNESDAY. A PACIFIC FRONT SHOULD
MOVE INTO WRN NEB LATE WEDNESDAY. THROUGH WEDNESDAY...500 MB HEIGHTS
WILL GRADUALLY FALL WHILE H700 MB TEMPS REMAIN NEAR STEADY AT
10C-12C. WIND SHEAR APPEARS TO GRADUALLY INCREASE SUPPORTING A
SLIGHT INCREASE IN BULK SHEAR. NEARLY ALL OF THE FCST AREA HAS BEEN
OUTLOOKED FOR SEVERE WEATHER BY SPC THROUGH WEDNESDAY. ALL
CONVECTION WHICH DEVELOPS TONIGHT THROUGH WEDNESDAY WILL HAVE A
LARGE IMPACT ON SUBSEQUENT STORM DEVELOPMENT AS RAIN COOLED OUTFLOW
DEVELOPS AND SETS UP FOCUS FOR SUCCEEDING STORM DEVELOPMENT. THUS THE
LOCATION OF HIGHEST POPS IS HIGHLY CONDITIONAL. A MULTI MODEL BLEND
WAS USED FOR POPS AND CAPPED AT 40 PERCENT. A SIMILAR STRATEGY WAS
USED FOR QPF. IN GENERAL NRN AND WRN NEB APPEAR MORE FAVORABLE FOR
STORM DEVELOPMENT THAT THE SOUTHWEST WHERE 700 MB WARM AIR ADVECTION
WILL OFTEN CAP THE ATMOSPHERE.
A SERIES OF PERTURBATIONS WILL CONTINUE TO EJECT FROM THE UPPER LOW
ACROSS THE NRN PACIFIC. THESE DISTURBANCES WILL MOVE THROUGH SD AND
NEB TRIGGERING STORM DEVELOPMENT. IN TIME THE UPPER LEVEL WILL BUILD
SOUTHEAST THROUGH PACIFIC NORTHWEST AND NRN ROCKIES. FALLING HEIGHTS
SHOULD MAINTAIN STEEP LAPSE RATES AND AN EML CONDUCIVE FOR STORM
DEVELOPMENT. AS LONG AS THE PACIFIC FRONT REMAINS WEST OF THE FCST
AREA...MOISTURE AND WARM AIR ADVECTION SHOULD CONTINUE PROVIDING
FUEL FOR STORM DEVELOPMENT.
WITH THE PERSISTENT MOISTURE ADVECTION...K INDICES INCREASE TO 40C
OR GREATER IN THE NAM AND GFS MODELS. THIS ALONG WITH THE FACT THAT
VERY HEAVY RAINFALL TOTALS HAVE OCCURRED FROM STORMS THIS LAST TWO
DAYS...SUGGEST SOME STORMS WILL PRODUCE LOCALLY HEAVY RAINFALL.
WEDNESDAY NIGHT THROUGH MONDAY MORNING...
THE PACIFIC FRONT WILL LIKELY CROSS THE FCST AREA WEDNESDAY
NIGHT...EARLY THURSDAY AT THE LATEST. THIS WILL SHUNT LOW LEVEL
MOISTURE EAST OF THE FCST AREA. H500 MB TEMPS FALL TO AROUND -18C
WHICH WOULD CONTINUE TO SUPPORT SHOWERS AND THUNDERSTORMS. THE
MODELS ARE IN GOOD AGREEMENT THAT AN UPPER LEVEL LOW WILL CIRCULATE
THROUGH THE NRN AND CNTL PLAINS. ALTHOUGH THE COLD CORE WILL LIKELY
CENTER ACROSS ND/SD...THERE SHOULD BE ENOUGH COLD AIR ALOFT ACROSS
THE FCST AREA TO DESTABILIZE THE ATMOSPHERE THURSDAY AND
FRIDAY...PERHAPS EVEN SATURDAY.
FCST MAX TEMPS WILL RISE INTO THE 60S AND 70S BEHIND THE FRONT
THURSDAY THROUGH MONDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1229 AM CDT MON MAY 27 2013
ISOLATED TO SCATTERED THUNDERSTORMS WILL CONTINUE OVER WESTERN
NEBRASKA THROUGH THE EARLY MORNING HOURS. STRATUS WILL DROP SOUTH IN
THE KVTN AREA INTO THE SANDHILLS THROUGH THE EARLY MORNING. IFR
CONDITIONS EXPECTED WITH IFR STRATUS CONDITIONS TO HOLD ON AT KVTN
THROUGH THE MORNING. SKIES TO GRADUALLY CLEAR OUT OVER WESTERN
NEBRASKA THROUGH THE AFTERNOON WITH THUNDERSTORMS
REDEVELOPING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...POWER
SYNOPSIS...CDC
SHORT TERM...JWS
LONG TERM...CDC
AVIATION...POWER
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1206 AM CDT MON MAY 27 2013
.UPDATE...
BOW ECHO OVER NORTHEAST NEBRASKA CONTINUES TO MOVE EAST AND
SOUTHEAST...WE SHOULD CONTINUE TO SEE SOME DEVELOPMENT INTO
SOUTHEAST NEBRASKA AND SOUTHWEST IOWA OVERNIGHT.
MILLER
&&
.AVIATION...
06Z TAFS FOR KOMA...KLNK...KOFK.
TSRA SHOULD CONTINUE IN THE KOFK AREA THE NEXT SEVERAL HOURS...
WITH THE STRONGEST ACTIVITY LIKELY BEFORE 07Z. THERE IS STILL
SOME UNCERTAINTY HOW FAR SOUTHEAST STORMS WILL REACH OVERNIGHT...
BUT HRRR MODEL DEVELOPS ACTIVITY TOWARD NORTHEAST KANSAS AND
NORTHWEST MISSOURI BY A LITTLE AFTER SUNRISE.
EXPECT A GRADUAL DECREASE IN CEILINGS THROUGH 14Z...THEN A GRADUAL
UPWARD TREND TOWARD VFR CONDITIONS AT ALL THREE SITES BY EARLY
AFTERNOON MONDAY.
MILLER
&&
.PREV DISCUSSION... /ISSUED 249 PM CDT SUN MAY 26 2013/
DISCUSSION...
VERY ACTIVE WEEK ON TAP OVER THE CNTRL PLAINS WITH POTENTIAL SVR
ACTIVITY ALONG WITH PROLONGED/EXCESSIVE PCPN. MORNING PRECIP WATER
PLOTS WERE SHOWING AMPLE GULF MOISTURE IN PLACE WITH VALUES ROUGHLY
150% OF NORM. LATEST MESOSCALE ANALYSIS INDICATING STOUT MOISTURE
STILL STREAMING INTO THE REGION...AND MODELS ARE IN GOOD AGREEMENT
THIS INFLUX OF MOISTURE WILL CONTINUE THRU AT LEAST
MIDWEEK...GUARANTEEING ENVIRONMENTAL MOISTURE CONTENT WILL REMAIN
QUITE HIGH. AS A MATTER OF FACT...THE GFS IS SUGGESTING TOTAL PCPN
AMOUNTS REACHING 400% OF NORM OVER IA BY NEXT SUNDAY GIVEN SUSTAINED
PCPN EFFICIENCY.
MEANWHILE...MODELS ARE AGAIN IN GOOD AGREEMENT LARGE SCALE FLOW THRU
THIS WEEK WILL GRADUALLY TRANSITION FROM A LARGE CLOSED LOW
CURRENTLY SITTING OVER THE PAC NW TO A RATHER IMPRESSIVE DEEP
ELONGATED LONGWAVE TROF WITH THE AXIS EXTENDING FROM THE ALASKAN
GULF TO THE SRN TIP OF TX. HEADING INTO NEXT WEEKEND THEN...MODELS
PROG THE WRN CONUS TROF BECOMING MORE BROAD IN NATURE WITH LITTLE
MOVEMENT.
FOR TONIGHT...STOUT 310K ISENTROPIC UPGLIDE IS THE DRIVING FORCE FOR
CONVECTIVE ACTIVITY. LIFT WILL BE FURTHER ENHANCED VIA UPPER DIVG
ASSOCIATED WITH RRQ OF JET MAX. MODELS ADVERTISE ENVIRONMENTAL
INSTABILITY WILL REMAIN HIGH OVERNIGHT WITH THE AXIS FOCUSED WEST OF
THE CWA WITHIN AREA OF BEST DEEP LYR SHEAR/MUCAPES. LATEST HRRR
INITIATES CONVECTION THIS EVEN INVOF THE INSTABILITY AXIS...THEN
GRADUALLY PUSHES IT EWD OVERNIGHT. AT THIS POINT CANNOT DISCOUNT A
FEW STORMS PRODUCING HAIL AND/OR STRONG WIND GUSTS.
AS FOR SVR POTENTIAL...SPC CONVECTIVE OUTLOOK KEEPS THE CWA IN THE
SLGT RISK THRU DAY 3. LOOKING AT MONDAY AFTN/EVENING...FAVORABLE
CONDITIONS APPEAR TO BE FOCUS INVOF THE SRN CWA ALONG A WARM FRONT
EXTENDING ALONG THE NEB/KS BORDER. COMBINATION OF DEEP LYR
SHEAR/EFFECTIVE SRH/MLCAPE/ML LCL SUGGEST AN ISOLATED TORNADO OR 2
WILL BE POSSIBLE. TUES AFTN/EVENING THEN...SVR POTENTIAL REMAINS
FOCUSED OVER THE SRN CWA ALONG A SFC BNDRY ALONG THE NEB/KS BORDER.
ENVIRONMENTAL CONDITIONS WILL QUITE SIMILAR WITH THE POTENTIAL FOR
PRODUCING AN ISOLATED TORNADO OR 2.
IN REGARDS TO POPS THE REST OF THIS WEEK...AM COMPELLED TO MAINTAIN
PCPN CHANCES THRU THE MAJORITY OF THE FCST PERIOD GIVEN MODELS
ADVERTISING PERSISTENT FORCING VIA UPPER LEVEL DIVERGENCE...SERIES
OF VORT IMPULSES...ISENTROPIC UPGLIDE...MEANDERING SFC
BOUNDARIES...AS WELL AS GENEROUS MOISTURE TO TAP INTO.
DEE
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1115 PM CDT SUN MAY 26 2013
.SYNOPSIS...
ISSUED AT 315 PM CDT SUN MAY 26 2013
A DEEP UPPER LEVEL LOW...CURRENTLY ACROSS THE NORTH PACIFIC...WILL
MIGRATE SLOWLY EAST THROUGH THE PACIFIC NORTHWEST AND INTO THE NRN
PLAINS THIS WEEK. A STRONG PACIFIC COLD FRONT WILL MOVE THROUGH
THE FCST AREA WEDNESDAY NIGHT OR THURSDAY. SEVERE WEATHER IS
POSSIBLE TODAY THROUGH WEDNESDAY AS LOW PRESSURE REMAINS QUASI
STATIONARY ACROSS ERN COLORADO AND FOCUSES...MOSITURE...WARM AIR
ADVECTION AND DRY.
&&
.UPDATE...
ISSUED AT 1114 PM CDT SUN MAY 26 2013
UPDATED FORECAST TO DROP TORNADO WATCH AND ISSUE SEVERE
THUNDERSTORM WATCH.
UPDATE ISSUED AT 743 PM CDT SUN MAY 26 2013
UPDATED FORECAST TO INCLUDE TORNADO WATCH FOR NORTH CENTRAL NEBRASKA.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 315 PM CDT SUN MAY 26 2013
TONIGHT AND MONDAY...CONVECTION LATE THIS AFTERNOON INTO THE
EVENING TONIGHT...THEN LOW CLOUDS FOG DEVELOPMENT TOWARD MORNING
REMAIN FORECAST ISSUES FOR THE SHORT TERM. WEAK COLD FRONT
ANALYZED FROM SOUTHWEST NEBRASKA SOUTHWARD INTO NW KS AND ERN CO.
WARM FRONT EXTENDS FROM SW INTO SC NEBRASKA WITH INVERTED TROUGH
NORTHWARD INTO SD. NUMEROUS OUTFLOW BOUNDARIES SHOW IN THE HAND
ANALYSIS AS WELL.
QUITE A VARIED RANGE OF SHORT TERM MODEL SOLUTIONS FOR THIS EVENING
AS HRRR AND HIRES ARW SUGGEST NOTHING ORGANIZED WILL DEVELOP SOUTH
OF I80 CORRIDOR...BUT DEVELOP A MCS ACROSS THE SANDHILLS IN THE
HIGHWAY 2 VCNTY AND MOVE IT EASTWARD OVERNIGHT. THE NAM /AND HIRES
NMM/ AS WELL AS GFS SUGGEST TWO AREAS OF DEVELOPMENT...THE FIRST IN
SIMILAR AREAS TO THE PREVIOUSLY MENTIONED MODELS /SANDHILLS/ AND A
SECOND IN THE VCNTY OF THE WARM FRONT WHICH ORGANIZES INTO A MCS AND
MOVES SOUTHEAST. FCST WILL GO WITH THE IDEA THAT TO SOME DEGREE BOTH
GROUPS OF SOLUTIONS HAVE REALISTIC POSSIBILITIES BASED ON BETTER DEEP
LAYER SHEAR ACROSS THE NORTH WHICH SHOULD ALLOW FOR A BETTER
ORGANIZATION ONCE DEVELOPMENT OCCURS IN THE SANDHILLS BY EVENING.
LOW LEVEL LAPSE RATES IN THIS AREA HOWEVER ARE NOT THE BEST AS WOULD
BE EXPECTED NORTH OF THE WARM FRONT...AND ALSO BELIEVE AIR MASS IS
STILL SOMEWHAT INFLUENCED IN THE LOW LAYERS AS A RESULT OF THE
OUTFLOW THAT WAS EVIDENT EARLIER THIS MORNING. LARGE HAIL STILL A
POSSIBILITY HERE THOUGH WITH VERY STEEP MID LEVEL LAPSE RATES...EVEN
IF STORMS ARE ELEVATED WHICH SEEMS LIKELY IN THIS AREA.
FURTHER SOUTH...LOW LEVEL LAPSE RATES ARE STEEPEST ACROSS ERN CO AND
NW KS AND HAVE SURGED EWD AHEAD OF LEE SFC LOW IN NW KS. GOOD
THETA-E ADVECTION NORTHEAST OF THIS AREA SHOULD ALLOW DEVELOPMENT IN
THIS AREAS AS WELL...THOUGH COVERAGE REMAINS IN QUESTION. SPC
MESOANALYSIS INDICATES SOME CAP STILL PRESENT HERE AND SINCE LARGE
SCALE FORCING IS BEST FURTHER NORTH THE EXTENT OF CAP EROSION IS
ALSO IN QUESTION. WOULD LIKE TO SEE BETTER SFC CONVERGENCE IN THESE
LOCATIONS TO BE MORE CERTAIN ABOUT INITIATION. IF SFC BASED
DEVELOPMENT DOES OCCUR SVR POTENTIAL WILL BE HIGH AS VERY GOOD ML
CAPE IS IN PLACE. THEREFORE...FCST INCLUDES POPS IN THESE AREAS BASED ON
PREVIOUS THINKING.
THE LAST FEW NIGHTS HAS SEEN A TENDENCY TO DEVELOP LOW CLOUD BEHIND
OUTFLOW BOUNDARIES TWD DAYBREAK AND BELIEVE THAT SHOULD BE THE CASE
ONCE AGAIN MONDAY MORNING. DEPICTING LOCATIONS IS DIFFICULT BUT
FAVORED AREAS EAST OF HIGHWAY 61 SEEM MOST LIKELY AND HAVE TRENDED
THE FCST THAT WAY. EVENTUAL HIGH TEMPS WILL BE HIGHLY DEPENDENT ON
THESE LOW CLOUD DEVELOPMENT AS WELL...BUT AS WITH THE LAST FEW DAYS
AFTERNOON MIXING SHOULD ALLOW 80S MOST PLACES.
CONVECTION AGAIN POSSIBLE MONDAY AFTERNOON. MODELS SUGGESTING UPPER
TROUGH WILL CONTINUE TO MOVE EASTWARD AND SHOULD ALLOW FOR A MORE
SOUTHERN LOCATION OF SFC FEATURES ONCE CONVECTIVE DEBRIS GIVES WAY.
SOMEWHAT BETTER UPPER PV ANOMALY LOOKS TO SWING OUT ONTO THE PLAINS
BY LATE AFTERNOON MONDAY.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 315 PM CDT SUN MAY 26 2013
SFC LOW PRESSURE WILL REMAIN TUCKED ACROSS ERN COLO FOCUSING
MOISTURE...DRY AIR AND WARM AIR ADVECTION ACROSS WRN AND NCNTL NEB.
THE SFC LOW WILL GRADUALLY DEEPEN TO AROUND 992 MB BY TUESDAY AND
CONTINUING NEAR 992 MB THROUGH WEDNESDAY. A PACIFIC FRONT SHOULD
MOVE INTO WRN NEB LATE WEDNESDAY. THROUGH WEDNESDAY...500 MB HEIGHTS
WILL GRADUALLY FALL WHILE H700 MB TEMPS REMAIN NEAR STEADY AT
10C-12C. WIND SHEAR APPEARS TO GRADUALLY INCREASE SUPPORTING A
SLIGHT INCREASE IN BULK SHEAR. NEARLY ALL OF THE FCST AREA HAS BEEN
OUTLOOKED FOR SEVERE WEATHER BY SPC THROUGH WEDNESDAY. ALL
CONVECTION WHICH DEVELOPS TONIGHT THROUGH WEDNESDAY WILL HAVE A
LARGE IMPACT ON SUBSEQUENT STORM DEVELOPMENT AS RAIN COOLED OUTFLOW
DEVELOPS AND SETS UP FOCUS FOR SUCCEEDING STORM DEVELOPMENT. THUS THE
LOCATION OF HIGHEST POPS IS HIGHLY CONDITIONAL. A MULTI MODEL BLEND
WAS USED FOR POPS AND CAPPED AT 40 PERCENT. A SIMILAR STRATEGY WAS
USED FOR QPF. IN GENERAL NRN AND WRN NEB APPEAR MORE FAVORABLE FOR
STORM DEVELOPMENT THAT THE SOUTHWEST WHERE 700 MB WARM AIR ADVECTION
WILL OFTEN CAP THE ATMOSPHERE.
A SERIES OF PERTURBATIONS WILL CONTINUE TO EJECT FROM THE UPPER LOW
ACROSS THE NRN PACIFIC. THESE DISTURBANCES WILL MOVE THROUGH SD AND
NEB TRIGGERING STORM DEVELOPMENT. IN TIME THE UPPER LEVEL WILL BUILD
SOUTHEAST THROUGH PACIFIC NORTHWEST AND NRN ROCKIES. FALLING HEIGHTS
SHOULD MAINTAIN STEEP LAPSE RATES AND AN EML CONDUCIVE FOR STORM
DEVELOPMENT. AS LONG AS THE PACIFIC FRONT REMAINS WEST OF THE FCST
AREA...MOISTURE AND WARM AIR ADVECTION SHOULD CONTINUE PROVIDING
FUEL FOR STORM DEVELOPMENT.
WITH THE PERSISTENT MOISTURE ADVECTION...K INDICES INCREASE TO 40C
OR GREATER IN THE NAM AND GFS MODELS. THIS ALONG WITH THE FACT THAT
VERY HEAVY RAINFALL TOTALS HAVE OCCURRED FROM STORMS THIS LAST TWO
DAYS...SUGGEST SOME STORMS WILL PRODUCE LOCALLY HEAVY RAINFALL.
WEDNESDAY NIGHT THROUGH MONDAY MORNING...
THE PACIFIC FRONT WILL LIKELY CROSS THE FCST AREA WEDNESDAY
NIGHT...EARLY THURSDAY AT THE LATEST. THIS WILL SHUNT LOW LEVEL
MOISTURE EAST OF THE FCST AREA. H500 MB TEMPS FALL TO AROUND -18C
WHICH WOULD CONTINUE TO SUPPORT SHOWERS AND THUNDERSTORMS. THE
MODELS ARE IN GOOD AGREEMENT THAT AN UPPER LEVEL LOW WILL CIRCULATE
THROUGH THE NRN AND CNTL PLAINS. ALTHOUGH THE COLD CORE WILL LIKELY
CENTER ACROSS ND/SD...THERE SHOULD BE ENOUGH COLD AIR ALOFT ACROSS
THE FCST AREA TO DESTABILIZE THE ATMOSPHERE THURSDAY AND
FRIDAY...PERHAPS EVEN SATURDAY.
FCST MAX TEMPS WILL RISE INTO THE 60S AND 70S BEHIND THE FRONT
THURSDAY THROUGH MONDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 659 PM CDT SUN MAY 26 2013
THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER WESTERN NEBRASKA THIS
EVENING. STRONG CAP IN PLACE AND NOT A GOOD TRIGGER MECHANISM. VFR
CEILINGS AND VISIBILITIES EXPECTED. HAVE INCLUDED A TEMPO GROUP
FOR THUNDERSTORMS AT BOTH KVTN AND KLBF. CONFIDENCE NOT HIGH THAT
THESE WILL DEVELOP. EAST WINDS OVER NIGHT WITH STRATUS AND MVFR
CEILINGS DEVELOPING AFTER 2706Z. THESE STRATUS WILL HOLD ON
THROUGH THE MORNING BEFORE LIFTING INTO VFR THROUGH THE AFTERNOON.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...POWER
SYNOPSIS...CDC
SHORT TERM...JWS
LONG TERM...CDC
AVIATION...POWER
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
937 PM EDT TUE MAY 28 2013
.SYNOPSIS...
A WARM FRONT WILL MOVE THROUGH THE AREA OVERNIGHT BRINGING WITH IT
A ROUND OF SHOWERS AND THUNDERSTORMS. BEHIND THE FRONT A LINGERING
CHANCE OF THUNDERSTORMS WILL EXIST WEDNESDAY AFTERNOON...SOME OF WHICH
COULD CONTAIN GUSTY WINDS. WE WILL EXPERIENCE DRIER WEATHER
THURSDAY AND FRIDAY BUT IT WILL BE HOT WITH TEMPERATURES WELL INTO
THE 80S TO NEAR 90.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
930 PM UPDATE...AREA OF SHOWERS AND SCATTERED THUNDERSTORMS NOW
ENTERING THE FINGER LAKES REGION AND CENTRAL SOUTHERN TIER. THIS
COMPLEX OF SHOWERS AND EMBEDDED THUNDERSTORMS WILL CROSS ALL OF
CENTRAL NY AND NE PA DURING THE NEXT SEVERAL HOURS. UPPED POPS TO
CATEGORICAL/HIGH LIKELY IN THE SHORT TERM AND EXPECT SCATTERED
THUNDERSTORMS WITH PRIMARILY CLOUD TO CLOUD LIGHTNING BASED ON
LATEST LIGHTNING DISPLAYS AND EXPECTATION THAT CONVECTION WILL
CONTINUE TO WEAKEN AS IT MOVES INTO A MORE STABLE AIRMASS.
CONVECTION WILL BE ASSOCAITED WITH HEAVY DOWNPOURS WITH HIGH
PWATS. A FEW SEVERE THUNDERSTORMS OCCURRED IN EXTREME NORTHWEST
PA AND THE WESTERN SOUTHERN TIER OF NY WHERE MIXED LAYER CAPES
WERE AROUND 500 J/KG.
7 PM UPDATE...WIDESPREAD AREA OF SHOWERS AND EMBEDDED THUNDERSTORMS
CURRENTLY OVER EASTERN LAKE ERIE AND NOW MOVING INTO EXTREME
WESTERN NY WILL CROSS CENTRAL NY BETWEEN 02Z-07Z. THIS ACTIVITY
IS LOCATED JUST NORTH OF THE SFC WARM FRONT AND IS BEING ENHANCED
BY A MID LEVEL SHORT WAVE CURRENTLY IN THE VCNTY OF NW PA. SEVERE
WEATHER IS NOT EXPECTED WITH THIS CONVECTION BUT HEAVY DOWNPOURS
WILL ACCOMPANY ANY THUNDERSTORMS WITH PWATS AROUND 1.50 INCHES.
THE SOUTHERN EXTENT OF THIS CONVECTION MAY REACH THE NRN TIER OF
PA.
330 PM UPDATE...
THE STEADIEST OF THE RAIN IS MOVING TO OUR EAST NOW. WILL MAINTAIN
LOW CHANCE TO SLIGHT CHANCE POPS THROUGH THE EVENING HOWEVER
BECAUSE WHILE MOST WILL SEE A LULL IN PRECIPITATION...ENOUGH SCT.
SHOWERS EXISTS AROUND TO WARRANT THESE POPS. MAIN ATTENTION
HOWEVER IS TO A LINE OF SHOWERS AND THUNDERSTORMS NOW NEAR
DETROIT. AS THE HRRR FIRST HINTED AT THIS MORNING...THE HIGHER
RESOLUTION MODELS SUCH AS THE ARW AND NMM ARE NOW FOLLOWING
CLOSELY BRINGING THIS AREA OF SHOWERS AND THUNDERSTORMS ACROSS
LAKE ERIE AND INTO OUR AREA. AT FIRST IT APPEARED THE MODELS MAY
BE TOO FAR NORTH WITH THIS FEATURE WITH THE BEST INSTABILITY
VALUES TO OUR SOUTHWEST OVER WESTERN PA. HOWEVER BASED ON WHAT IS
HAPPENING NOW...IT APPEARS THE CONVECTION WILL RIDE ALONG THE
NORTHERN GRADIENT OF THE INSTABILITY...WHICH WILL FAVOR THE FINGER
LAKES AND CENTRAL NEW YORK BETWEEN 03Z AND 07Z. THE SOUTHERN EDGE
OF THE PRECIP SHOULD BE THE SOUTHERN TIER OF NY...WITH NOT AS MUCH
HAPPENING FARTHER SOUTH TOWARD KAVP. THUNDER IS LIKELY WITH THIS
AREA OF RAIN AS IT MOVES EAST. WHILE SURFACE BASED CAPES ARE EITHER 0
OR JUST A FEW HUNDRED J/KG...WE ARE SEEING LIGHTNING NOW NEAR
DETROIT WITH THE SAME VALUES. IN ADDITION SHOWALTER VALUES GO
NEGATIVE OVERNIGHT. ALL AND ALL LOOKING AT A 2 TO 4 HOUR PERIOD OF
HEAVIER RAIN WITH THUNDER A GOOD BET. AS THE WARM FRONT LIFTS
THROUGH OUR AREA CHANCES FOR POPS WILL DECREASE TOWARD DAYBREAK
WHILE LIFTING NORTHEAST TOWARD THE MOHAWK VALLY.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY NIGHT/...
330 PM UPDATE...
THE AREA REMAINS IN A SLIGHT RISK FOR SEVERE WEATHER WEDNESDAY AND
IT HAS BEEN EXPANDED A BIT FARTHER SOUTH THAN THE EARLY MORNING
UPDATE FROM SPC. IT STILL APPEARS THE BEST THREAT FOR STORMS WILL
BE DURING THE AFTERNOON AND FROM THE NORTHERN TIER COUNTIES OF PA
NORTH THROUGH CNY WHICH WILL BE CLOSER TO THE BEST UPPER LEVEL LIFT.
MOST IF NOT ALL OF THE AREA SHOULD BE IN THE WARM SECTOR WITH THE
WARM FRONT EITHER ACROSS OUR FAR NORTHEAST IF NOT OVER NNY. THIS
COMBINED WITH A SHORT WAVE MOVING CLOSE BUT JUST TO OUR NORTH AND
0-6 KM BULK SHEAR VALUES OF 30 KTS GIVE US THE POTENTIAL FOR
DAMAGING WINDS AND HAIL. HIGHER RESOLUTION MODELS AT THIS EARLY
STAGE POINT TOWARD A LINEAR SQUALL LINE MOVING THROUGH BETWEEN 18Z
AND 0Z. WILL CONTINUE WITH HIGH CHANCE TO LIKELY POPS AND CONTINUE
TO MENTION GUSTY WINDS IN THE FORECAST AND HWO.
AFTER THE CONVECTION DIES DOWN WEDNESDAY EVENING...THE MAIN STORY
WILL BE THE HEAT BUILDING INTO OUR AREA. WHILE BOTH THE NAM AND
GFS SUGGEST LOW CHANCE POPS LATE THURSDAY AFTERNOON ACROSS THE
NORTH AND FRIDAY AFTERNOON OVER WESTERN NY...A DEVELOPING CAP
AROUND 10KT SHOULD KEEP OUR IMPRESSIVE CAPE VALUES FROM BEING A
PROBLEM. 850 TEMPS BETWEEN 15C TO 18C SUPPORT HIGHS WELL INTO THE
80S BOTH DAYS...WITH NEAR 90 OR LOWER 90S LIKELY ESPECIALLY BY
FRIDAY IN THE LOWER ELEVATIONS.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
220 PM UPDATE...
VRY FEW CHGS NEEDED TO LONG TERM FCST THIS AFTN. ONLY TWEAK WAS
TO INCRS POPS AS IT LOOKS TO BE FAIRLY REASONABLE THAT ALL MODELS,
INCLUDING ENSEMBLES, SHOWING FROPA OCCURRING ARND 12Z MONDAY.
THUS, HV BOOSTED POPS TO LKLY SUN NGT FOR STARTERS THO THESE MAY
NEED TO BE TWEAKED WITH LATER FCSTS.
MED RANGE GUIDANCE ALSO HINTING THAT TROFFING WL BE MVG TWD THE
WRN LAKES ON SUN NGT. WITH THIS FEATURE MVG CLOSER TO CWA, CLDS WL
OVRSPRD THE REGION DRG THE DAY SUNDAY WITH SLGTLY COOLER TEMPS
EXPECTED, THO STILL ABV NORMAL.
&&
.AVIATION /01Z WEDNESDAY THROUGH SUNDAY/...
WDSPRD IFR/MVFR TNGT DUE TO PCPN/CIGS AND BR...WITH BGM/ELM/ITH
BLO ALTERNATE MINS AT TIMES TNGT. XPCT AREA OF SHRA/TSRA OVER WRN
NY TO CONTINUE TO MOV EWD ACRS ACRS THE RGN THIS EVNG ALTHO SYSTEM
WILL LIKELY BE WEAKENING BY THIS TIME. CAN`T RULE OUT SCT
CONVECTION LATER TNGT WITH WMFNT IN THE VCNTY. LATER TMRW
MRNG...XPCT IMPRVG CONDITIONS WITH MOST SITES IMPRVG TO VFR...LAST
SITES TO SEE IMPRVMNT WILL LIKELY BE SYR/RME. POTNL FOR MORE CONVECTION
SPCLY TMRW AFTN...BUT FOR NOW RESTRICTED MENTION TO SYR/RME WHERE
DYNAMICS SHUD BE A BIT STRONGER DUE TO PASSING S/WV. WINDS TNGT S
TO SE 5-10 KTS...BECMG SWLY ON TUE MRNG 10-15 KTS WITH G20-25 IN
THE AFTN.
OUTLOOK...
WED...MVFR IN SCT SHRA/TSRA.
THU-SAT...MAINLY VFR.
SUN...POTENTIAL FOR MVFR IN SHRA/TSRA AS COLD FRONT APPROACHES.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...HEDEN
NEAR TERM...HEDEN/RRM
SHORT TERM...HEDEN
LONG TERM...PVN
AVIATION...
AREA FORECAST DISCUSSION
NWS BUFFALO NY
740 PM EDT TUE MAY 28 2013
.SYNOPSIS...
A WARM FRONT WILL MOVE ACROSS NEW YORK STATE THIS EVENING AND
TONIGHT WITH NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS THROUGH
MID DAY WEDNESDAY. BEHIND THIS WARM FRONT A HOT AND HUMID AIRMASS
WILL BUILD INTO THE REGION FOR THE SECOND HALF OF THE WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
A WARM FRONT EXTENDING FROM THE CENTRAL LAKES AND INTO FAR WESTERN
NEW YORK WILL GRADUALLY LIFT TO THE NORTH OVERNIGHT. A SERIES OF
DISTURBANCES WILL RIDE ALONG THIS BOUNDARY...WHICH WILL BRING
SEVERAL OPPORTUNITIES FOR SHOWERS AND THUNDERSTORMS TONIGHT.
AT 730 PM...RADAR SHOWS A LARGE AREA OF SHOWER`S AND THUNDERSTORMS
ACROSS EASTERN LAKE ERIE AND WESTERN LAKE ONTARIO. THE MAJORITY
OF THIS ACTIVITY IS ELEVATED IN NATURE...HOWEVER THE SOUTHERN
PORTION OF THIS LINE IS SURFACE BASED...WITH STRONGER EMBEDDED
CELLS ALSO MIXING DOWN SOME WINDS. THIS AREA WILL MOVE ACROSS
WESTERN NEW YORK THIS EVENING...BRINGING A ROUND OF MODERATE TO
HEAVY RAINS...WITH SOME EMBEDDED THUNDERSTORMS. THE SEVERE
POTENTIAL REMAINS LIMITED...WITH MOST OF THIS CONVECTION
ELEVATED...WITH THE BEST CHANCE FOR STRONG STORMS ON THE SOUTHERN
EDGE OF THIS LINE IN NORTHWESTERN PENNSYLVANIA. THE HRRR MODEL HAS
A REASONABLE HANDLE ON THIS.
LATER THIS EVENING...MODEL CONSENSUS SUGGESTS THAT THIS CONVECTION
WILL SHIFT NORTH AS THE WARM FRONTAL BOUNDARY MOVES NORTH.
FOLLOWING THIS...THE BEST CHANCE FOR SHOWERS AND THUNDERSTORMS
AFTER MIDNIGHT SHOULD BE ACROSS AND/OR NORTH OF LAKE ONTARIO...EVENTUALLY
MOVING EAST OF LAKE ONTARIO LATE TONIGHT.
A WARMER AND MORE HUMID AIRMASS WILL SPREAD ACROSS THE REGION
TONIGHT BEHIND THE WARM FRONT. THE WARMING TREND THE PAST COUPLE OF
NIGHTS WILL BE EVEN MORE NOTICEABLE TONIGHT WITH THE INCREASED
HUMIDITY. EXPECT OVERNIGHT LOWS TO DROP BACK INTO THE UPPER 50S TO
LOWER 60S.
THE FRONT WILL CONTINUE IT NORTHWARD MOTION AND TAKE MOST OF THE
PRECIPITATION THREAT TO CENTRAL AND NORTHERN NEW YORK BY THE END OF
WEDNESDAY. 850MB TEMPS WILL RISE TO +14C WITH AFTERNOON HIGH TEMPS
REACHING THE MID 70S TO LOWER 80S ACROSS THE REGION...EVEN WITH
CLOUD COVER AND THE PRECIPITATION.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
MID SUMMER WARMTH WILL CHARACTERIZE THIS PERIOD AS RIDGING CENTERED
OVER THE MID ATLANTIC STATES WILL KEEP A CONTINUAL FEED OF 16 TO 18C
H85 AIR POURING FROM THE UPPER OHIO VALLEY ACROSS OUR FORECAST AREA.
THIS WILL HOLD OUR TEMPERATURES UP SOME 15 DEGREES F ABOVE NORMAL...
AND AT THIS TIME OF YEAR...THAT TRANSLATES INTO VERY WARM CONDITIONS
WITH DAYTIME HIGHS OF 85 TO 90 AND LOWS IN THE LOW TO MID 60S.
DIGGING INTO THE DETAILS...
A WEAKENING MID LEVEL FRONTAL BOUNDARY WILL CONTINUE TO WASH OUT
ACROSS OUR FORECAST AREA WEDNESDAY NIGHT WHILE THE NOSE OF A H5
RIDGE WILL POKE NORTHWARDS ACROSS THE LOWER GREAT LAKES. OTHER THAN
A STRAY EVENING SHOWER...THIS WILL LEAVE US WITH A WARM DRY NIGHT.
THE RIDGE WILL CONTINUE TO AMPLIFY ACROSS OUR REGION ON THURSDAY.
DESPITE DIURNALLY BASED INSTABILITY IN THE LOW LEVELS (LAPSE RATES
OF 9-11 DEG C/KM)...THE ASSOCIATED SUBSIDENCE AND PRESENCE OF A
FAIRLY STRONG CAP (10K FT) WILL KEEP ANY CONVECTION FROM FIRING. AS
A RESULT WE CAN LOOK FORWARD TO A SUNNY AND VERY WARM DAY WITH
AFTERNOON TEMPERATURES TOPPING OUT BETWEEN 85 AND 90 AWAY FROM THE
LAKES. THE HEAT WILL BE TEMPERED A BIT IN BUFFALO WHERE A STRONG
LAKE BREEZE WILL BE IN PLACE.
THURSDAY NIGHT WILL BE A CARBON COPY OF THE PREVIOUS NIGHT...ALBEIT
IT A DEGREE OR TWO WARMER AS TEMPERATURES ACROSS THE MAJORITY OF THE
FORECAST AREA WILL NOT DROP OUT OF THE MID AND UPPER 60S. IT WILL
CERTAINLY FEEL LIKE MID SUMMER. NORMALS LOWS FOR THIS TIME OF YEAR
ARE WITHIN A COUPLE DEGREES OF 50.
ENERGY EJECTING ACROSS THE UPPER GREAT LAKES FROM A BROAD CLOSED H5
LOW OVER THE NORTHERN PLAINS WILL FLATTEN THE CREST OF THE SUMMER
RIDGE OVER OUR AREA ON FRIDAY. WHILE THE VAST MAJORITY OF OUR
FORECAST AREA WILL REMAIN RAINFREE...THIS MAY BE JUST ENOUGH TO
ALLOW FOR THE RELEASE OF SOME OF THE IMPRESSIVE DIURNAL INSTABILITY
THAT WILL BE IN PLACE. SBCAPES ARE EXPECTED TO CLIMB TO BETWEEN 1500
AND 2000 J/KG FRIDAY AFTERNOON...BUT UNLIKE THURSDAY WHEN A FAIRLY
STRONG CAP IS FORECAST...SUBTLE COOLING AT H7 WILL EITHER ELIMINATE
THE CAP FROM THE PREVIOUS DAY OR AT THE LEAST...WEAKEN IT. THIS
COULD SET THE STAGE FOR SOME ROBUST CONVECTION ACROSS PARTS OF THE
SRN TIER AND FINGER LAKES REGION WHERE AN EASTWARD PROPAGATING LAKE
BREEZE BOUNDARY WILL LIKELY BE FOUND. WILL INTRODUCE SLGT/LOW CHC
POPS FOR THAT PARTICULAR AREA. OTHERWISE...THE VERY WARM AND SULTRY
CONDITIONS WILL CONTINUE WITH AFTERNOON HIGHS WILL GENERALLY BE IN
THE UPPER 80S TO LOWER 90S AWAY FROM THE LAKES.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
MERCURY READINGS WILL ONCE AGAIN TOP OUT IN THE MID TO UPPER 80S
ACROSS WNY ON SATURDAY...BUT COOLER TEMPS WILL ARRIVE DURING THE
LATTER HALF OF THE WEEKEND ALONG WITH INCREASING CHANCES FOR
PRECIPITATION (SHOWERS AND THUNDERSTORMS). THE CULPRIT...A PAIR OF
ROBUST SHORTWAVES WITHIN A CLOSED CIRCULATION OVER THE NORTHERN
PLAINS THAT WILL EJECT ACROSS THE UPPER GREAT LAKES...AND
EVENTUALLY SOUTHERN ONTARIO.
PER ECMWF/GFS...THE BEST SHOT AT WIDESPREAD SHOWERS/THUNDERSTORMS
WILL ARRIVE SATURDAY NIGHT INTO EARLY SUNDAY AS A VIGOROUS SHORTWAVE
RIDES ALONG THE FRONT AND THE COLD FRONT SLOWLY PUSHING ACROSS WNY.
SHOWERS AND THUNDERSTORMS WILL SLOWLY COME TO AN END FROM WEST TO
EAST SUNDAY EVENING/NIGHT AS THE COLD FRONT EXITS TO OUR EAST.
MONDAY...EXPECT MUCH COOLER WEATHER BEHIND THE FRONT (HIGHS IN THE
MID TO UPPER 60S) AND SOME LINGERING SHOWER ACTIVITY...PRIMARILY
ACROSS THE NORTH COUNTRY AS THE UPPER-LEVEL TROUGH SWINGS ACROSS THE
REGION. HIGH PRESSURE ALOFT AND AT THE SFC BUILDS OVER WNY TUESDAY
WITH A BRIEF RETURN TO DRY WEATHER AND WARMING SFC TEMPS.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
AT 23Z...A LARGE AREA OF SHOWERS AND THUNDERSTORMS WAS ACROSS
EASTERN PORTIONS OF LAKE ERIE...AND WESTERN LAKE ONTARIO. THIS
AREA WILL MOVE ACROSS WESTERN NEW YORK THROUGH 03Z...AND LIKELY
WEAKEN AS IT MOVES EASTWARD. EXPECT A PERIOD OF HEAVY RAIN WITH
THIS...AND PROBABLY A FEW LIGHTNING STRIKES AT THE BUF/IAG/JHW TAF
LOCATIONS. HAVE LOWER CONFIDENCE...BUT IT MAY CONTINUE TO IMPACT
ROC/ART LATE EVENING AND OVERNIGHT.
CONDITIONS SHOULD MAINLY BE IN THE MVFR/VFR CATEGORIES...BUT
WILL BE LOCALLY LOWER IN THUNDERSTORMS. BEHIND THIS WARM FRONT A
LLJ AROUND 40 TO 45 KNOTS AT 2K FEET WILL CROSS NEW YORK STATE
THIS EVENING AND TONIGHT. THIS WILL RESULT IN LLWS.
ON WEDNESDAY...STEADIEST SHOWERS AND THUNDERSTORMS WILL TAPER OFF
DURING THE AFTERNOON. EXPECT MAINLY VFR CONDITIONS...OUTSIDE OF THE
CONVECTION WHICH MAY LOWER CONDITIONS TO IFR OR LOWER AT TIMES.
OUTLOOK...
WEDNESDAY NIGHT THROUGH SATURDAY...MAINLY VFR.
SUNDAY...MVFR WITH RAIN SHOWERS.
&&
.MARINE...
A WARM FRONT WILL LIFT ACROSS THE EASTERN GREAT LAKE WATER BODIES
TONIGHT WITH SHOWERS AND THUNDERSTORMS. WAVES WILL REMAIN LIGHT...
GENERALLY ONLY AROUND 1 FOOT...ALTHOUGH ANY THUNDERSTORM COULD KICK UP
WINDS AND WATERS BRIEFLY.
WINDS WILL INCREASE ON WEDNESDAY OUT OF THE SOUTHWEST AS THE
PRESSURE GRADIENT TIGHTENS. WINDS AND WAVES MAY GET CLOSE TO SMALL
CRAFT ADVISORY CRITERIA ON BOTH LAKES ERIE AND ONTARIO...ALTHOUGH IT
APPEARS THAT WINDS AND WAVES WILL REMAIN JUST BELOW CRITERIA.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...WCH
NEAR TERM...APFFEL/WCH
SHORT TERM...RSH
LONG TERM...AR
AVIATION...APFFEL
MARINE...APFFEL/WCH
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
731 PM EDT TUE MAY 28 2013
.SYNOPSIS...
A WARM FRONT WILL MOVE THROUGH THE AREA OVERNIGHT BRINGING WITH IT
A ROUND OF SHOWERS AND THUNDERSTORMS. BEHIND THE FRONT A LINGERING
CHANCE OF THUNDERSTORMS WILL EXIST WEDNESDAY AFTERNOON...SOME OF WHICH
COULD CONTAIN GUSTY WINDS. WE WILL EXPERIENCE DRIER WEATHER
THURSDAY AND FRIDAY BUT IT WILL BE HOT WITH TEMPERATURES WELL INTO
THE 80S TO NEAR 90.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
7 PM UPDATE...WIDESPREAD AREA OF SHOWERS AND EMBEDDED THUNDERSTORMS
CURRENTLY OVER EASTERN LAKE ERIE AND NOW MOVING INTO EXTREME
WESTERN NY WILL CROSS CENTRAL NY BETWEEN 02Z-07Z. THIS ACTIVITY
IS LOCATED JUST NORTH OF THE SFC WARM FRONT AND IS BEING ENHANCED
BY A MID LEVEL SHORT WAVE CURRENTLY IN THE VCNTY OF NW PA. SEVERE
WEATHER IS NOT EXPECTED WITH THIS CONVECTION BUT HEAVY DOWNPOURS
WILL ACCOMPANY ANY THUNDERSTORMS WITH PWATS AROUND 1.50 INCHES.
THE SOUTHERN EXTENT OF THIS CONVECTION MAY REACH THE NRN TIER OF
PA.
330 PM UPDATE...
THE STEADIEST OF THE RAIN IS MOVING TO OUR EAST NOW. WILL MAINTAIN
LOW CHANCE TO SLIGHT CHANCE POPS THROUGH THE EVENING HOWEVER
BECAUSE WHILE MOST WILL SEE A LULL IN PRECIPITATION...ENOUGH SCT.
SHOWERS EXISTS AROUND TO WARRANT THESE POPS. MAIN ATTENTION
HOWEVER IS TO A LINE OF SHOWERS AND THUNDERSTORMS NOW NEAR
DETROIT. AS THE HRRR FIRST HINTED AT THIS MORNING...THE HIGHER
RESOLUTION MODELS SUCH AS THE ARW AND NMM ARE NOW FOLLOWING
CLOSELY BRINGING THIS AREA OF SHOWERS AND THUNDERSTORMS ACROSS
LAKE ERIE AND INTO OUR AREA. AT FIRST IT APPEARED THE MODELS MAY
BE TOO FAR NORTH WITH THIS FEATURE WITH THE BEST INSTABILITY
VALUES TO OUR SOUTHWEST OVER WESTERN PA. HOWEVER BASED ON WHAT IS
HAPPENING NOW...IT APPEARS THE CONVECTION WILL RIDE ALONG THE
NORTHERN GRADIENT OF THE INSTABILITY...WHICH WILL FAVOR THE FINGER
LAKES AND CENTRAL NEW YORK BETWEEN 03Z AND 07Z. THE SOUTHERN EDGE
OF THE PRECIP SHOULD BE THE SOUTHERN TIER OF NY...WITH NOT AS MUCH
HAPPENING FARTHER SOUTH TOWARD KAVP. THUNDER IS LIKELY WITH THIS
AREA OF RAIN AS IT MOVES EAST. WHILE SURFACE BASED CAPES ARE EITHER 0
OR JUST A FEW HUNDRED J/KG...WE ARE SEEING LIGHTNING NOW NEAR
DETROIT WITH THE SAME VALUES. IN ADDITION SHOWALTER VALUES GO
NEGATIVE OVERNIGHT. ALL AND ALL LOOKING AT A 2 TO 4 HOUR PERIOD OF
HEAVIER RAIN WITH THUNDER A GOOD BET. AS THE WARM FRONT LIFTS
THROUGH OUR AREA CHANCES FOR POPS WILL DECREASE TOWARD DAYBREAK
WHILE LIFTING NORTHEAST TOWARD THE MOHAWK VALLY.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY NIGHT/...
330 PM UPDATE...
THE AREA REMAINS IN A SLIGHT RISK FOR SEVERE WEATHER WEDNESDAY AND
IT HAS BEEN EXPANDED A BIT FARTHER SOUTH THAN THE EARLY MORNING
UPDATE FROM SPC. IT STILL APPEARS THE BEST THREAT FOR STORMS WILL
BE DURING THE AFTERNOON AND FROM THE NORTHERN TIER COUNTIES OF PA
NORTH THROUGH CNY WHICH WILL BE CLOSER TO THE BEST UPPER LEVEL LIFT.
MOST IF NOT ALL OF THE AREA SHOULD BE IN THE WARM SECTOR WITH THE
WARM FRONT EITHER ACROSS OUR FAR NORTHEAST IF NOT OVER NNY. THIS
COMBINED WITH A SHORT WAVE MOVING CLOSE BUT JUST TO OUR NORTH AND
0-6 KM BULK SHEAR VALUES OF 30 KTS GIVE US THE POTENTIAL FOR
DAMAGING WINDS AND HAIL. HIGHER RESOLUTION MODELS AT THIS EARLY
STAGE POINT TOWARD A LINEAR SQUALL LINE MOVING THROUGH BETWEEN 18Z
AND 0Z. WILL CONTINUE WITH HIGH CHANCE TO LIKELY POPS AND CONTINUE
TO MENTION GUSTY WINDS IN THE FORECAST AND HWO.
AFTER THE CONVECTION DIES DOWN WEDNESDAY EVENING...THE MAIN STORY
WILL BE THE HEAT BUILDING INTO OUR AREA. WHILE BOTH THE NAM AND
GFS SUGGEST LOW CHANCE POPS LATE THURSDAY AFTERNOON ACROSS THE
NORTH AND FRIDAY AFTERNOON OVER WESTERN NY...A DEVELOPING CAP
AROUND 10KT SHOULD KEEP OUR IMPRESSIVE CAPE VALUES FROM BEING A
PROBLEM. 850 TEMPS BETWEEN 15C TO 18C SUPPORT HIGHS WELL INTO THE
80S BOTH DAYS...WITH NEAR 90 OR LOWER 90S LIKELY ESPECIALLY BY
FRIDAY IN THE LOWER ELEVATIONS.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
220 PM UPDATE...
VRY FEW CHGS NEEDED TO LONG TERM FCST THIS AFTN. ONLY TWEAK WAS
TO INCRS POPS AS IT LOOKS TO BE FAIRLY REASONABLE THAT ALL MODELS,
INCLUDING ENSEMBLES, SHOWING FROPA OCCURRING ARND 12Z MONDAY.
THUS, HV BOOSTED POPS TO LKLY SUN NGT FOR STARTERS THO THESE MAY
NEED TO BE TWEAKED WITH LATER FCSTS.
MED RANGE GUIDANCE ALSO HINTING THAT TROFFING WL BE MVG TWD THE
WRN LAKES ON SUN NGT. WITH THIS FEATURE MVG CLOSER TO CWA, CLDS WL
OVRSPRD THE REGION DRG THE DAY SUNDAY WITH SLGTLY COOLER TEMPS
EXPECTED, THO STILL ABV NORMAL.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
WDSPRD IFR/MVFR TNGT DUE TO PCPN/CIGS AND BR...WITH BGM/ELM/ITH
BLO ALTERNATE MINS AT TIMES TNGT. XPCT AREA OF SHRA/TSRA OVER WRN
NY TO CONTINUE TO MOV EWD ACRS ACRS THE RGN THIS EVNG ALTHO SYSTEM
WILL LIKELY BE WEAKENING BY THIS TIME. CAN`T RULE OUT SCT
CONVECTION LATER TNGT WITH WMFNT IN THE VCNTY. LATER TMRW
MRNG...XPCT IMPRVG CONDITIONS WITH MOST SITES IMPRVG TO VFR...LAST
SITES TO SEE IMPRVMNT WILL LIKELY BE SYR/RME. POTNL FOR MORE CONVECTION
SPCLY TMRW AFTN...BUT FOR NOW RESTRICTED MENTION TO SYR/RME WHERE
DYNAMICS SHUD BE A BIT STRONGER DUE TO PASSING S/WV. WINDS TNGT S
TO SE 5-10 KTS...BECMG SWLY ON TUE MRNG 10-15 KTS WITH G20-25 IN
THE AFTN.
OUTLOOK...
WED...MVFR IN SCT SHRA/TSRA.
THU-SAT...MAINLY VFR.
SUN...POTENTIAL FOR MVFR IN SHRA/TSRA AS COLD FRONT APPROACHES.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...HEDEN
NEAR TERM...HEDEN/RRM
SHORT TERM...HEDEN
LONG TERM...PVN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
721 PM EDT TUE MAY 28 2013
.SYNOPSIS...
A WARM FRONT WILL MOVE THROUGH THE AREA OVERNIGHT BRINGING WITH IT
A ROUND OF SHOWERS AND THUNDERSTORMS. BEHIND THE FRONT A LINGERING
CHANCE OF THUNDERSTORMS WILL EXIST WEDNESDAY AFTERNOON...SOME OF WHICH
COULD CONTAIN GUSTY WINDS. WE WILL EXPERIENCE DRIER WEATHER
THURSDAY AND FRIDAY BUT IT WILL BE HOT WITH TEMPERATURES WELL INTO
THE 80S TO NEAR 90.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
7 PM UPDATE...WIDESPREAD AREA OF SHOWERS AND EMBEDDED THUNDERSTORMS
CURRENTLY OVER EASTERN LAKE ERIE AND NOW MOVING INTO EXTREME
WESTERN NY WILL CROSS CENTRAL NY BETWEEN 02Z-07Z. THIS ACTIVITY
IS LOCATED JUST NORTH OF THE SFC WARM FRONT AND IS BEING ENHANCED
BY A MID LEVEL SHORT WAVE CURRENTLY IN THE VCNTY OF NW PA. SEVERE
WEATHER IS NOT EXPECTED WITH THIS CONVECTION BUT HEAVY DOWNPOURS
WILL ACCOMPANY ANY THUNDERSTORMS WITH PWATS AROUND 1.50 INCHES.
THE SOUTHERN EXTENT OF THIS CONVECTION MAY REACH THE NRN TIER OF
PA.
330 PM UPDATE...
THE STEADIEST OF THE RAIN IS MOVING TO OUR EAST NOW. WILL MAINTAIN
LOW CHANCE TO SLIGHT CHANCE POPS THROUGH THE EVENING HOWEVER
BECAUSE WHILE MOST WILL SEE A LULL IN PRECIPITATION...ENOUGH SCT.
SHOWERS EXISTS AROUND TO WARRANT THESE POPS. MAIN ATTENTION
HOWEVER IS TO A LINE OF SHOWERS AND THUNDERSTORMS NOW NEAR
DETROIT. AS THE HRRR FIRST HINTED AT THIS MORNING...THE HIGHER
RESOLUTION MODELS SUCH AS THE ARW AND NMM ARE NOW FOLLOWING
CLOSELY BRINGING THIS AREA OF SHOWERS AND THUNDERSTORMS ACROSS
LAKE ERIE AND INTO OUR AREA. AT FIRST IT APPEARED THE MODELS MAY
BE TOO FAR NORTH WITH THIS FEATURE WITH THE BEST INSTABILITY
VALUES TO OUR SOUTHWEST OVER WESTERN PA. HOWEVER BASED ON WHAT IS
HAPPENING NOW...IT APPEARS THE CONVECTION WILL RIDE ALONG THE
NORTHERN GRADIENT OF THE INSTABILITY...WHICH WILL FAVOR THE FINGER
LAKES AND CENTRAL NEW YORK BETWEEN 03Z AND 07Z. THE SOUTHERN EDGE
OF THE PRECIP SHOULD BE THE SOUTHERN TIER OF NY...WITH NOT AS MUCH
HAPPENING FARTHER SOUTH TOWARD KAVP. THUNDER IS LIKELY WITH THIS
AREA OF RAIN AS IT MOVES EAST. WHILE SURFACE BASED CAPES ARE EITHER 0
OR JUST A FEW HUNDRED J/KG...WE ARE SEEING LIGHTNING NOW NEAR
DETROIT WITH THE SAME VALUES. IN ADDITION SHOWALTER VALUES GO
NEGATIVE OVERNIGHT. ALL AND ALL LOOKING AT A 2 TO 4 HOUR PERIOD OF
HEAVIER RAIN WITH THUNDER A GOOD BET. AS THE WARM FRONT LIFTS
THROUGH OUR AREA CHANCES FOR POPS WILL DECREASE TOWARD DAYBREAK
WHILE LIFTING NORTHEAST TOWARD THE MOHAWK VALLY.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY NIGHT/...
330 PM UPDATE...
THE AREA REMAINS IN A SLIGHT RISK FOR SEVERE WEATHER WEDNESDAY AND
IT HAS BEEN EXPANDED A BIT FARTHER SOUTH THAN THE EARLY MORNING
UPDATE FROM SPC. IT STILL APPEARS THE BEST THREAT FOR STORMS WILL
BE DURING THE AFTERNOON AND FROM THE NORTHERN TIER COUNTIES OF PA
NORTH THROUGH CNY WHICH WILL BE CLOSER TO THE BEST UPPER LEVEL LIFT.
MOST IF NOT ALL OF THE AREA SHOULD BE IN THE WARM SECTOR WITH THE
WARM FRONT EITHER ACROSS OUR FAR NORTHEAST IF NOT OVER NNY. THIS
COMBINED WITH A SHORT WAVE MOVING CLOSE BUT JUST TO OUR NORTH AND
0-6 KM BULK SHEAR VALUES OF 30 KTS GIVE US THE POTENTIAL FOR
DAMAGING WINDS AND HAIL. HIGHER RESOLUTION MODELS AT THIS EARLY
STAGE POINT TOWARD A LINEAR SQUALL LINE MOVING THROUGH BETWEEN 18Z
AND 0Z. WILL CONTINUE WITH HIGH CHANCE TO LIKELY POPS AND CONTINUE
TO MENTION GUSTY WINDS IN THE FORECAST AND HWO.
AFTER THE CONVECTION DIES DOWN WEDNESDAY EVENING...THE MAIN STORY
WILL BE THE HEAT BUILDING INTO OUR AREA. WHILE BOTH THE NAM AND
GFS SUGGEST LOW CHANCE POPS LATE THURSDAY AFTERNOON ACROSS THE
NORTH AND FRIDAY AFTERNOON OVER WESTERN NY...A DEVELOPING CAP
AROUND 10KT SHOULD KEEP OUR IMPRESSIVE CAPE VALUES FROM BEING A
PROBLEM. 850 TEMPS BETWEEN 15C TO 18C SUPPORT HIGHS WELL INTO THE
80S BOTH DAYS...WITH NEAR 90 OR LOWER 90S LIKELY ESPECIALLY BY
FRIDAY IN THE LOWER ELEVATIONS.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
220 PM UPDATE...
VRY FEW CHGS NEEDED TO LONG TERM FCST THIS AFTN. ONLY TWEAK WAS
TO INCRS POPS AS IT LOOKS TO BE FAIRLY REASONABLE THAT ALL MODELS,
INCLUDING ENSEMBLES, SHOWING FROPA OCCURRING ARND 12Z MONDAY.
THUS, HV BOOSTED POPS TO LKLY SUN NGT FOR STARTERS THO THESE MAY
NEED TO BE TWEAKED WITH LATER FCSTS.
MED RANGE GUIDANCE ALSO HINTING THAT TROFFING WL BE MVG TWD THE
WRN LAKES ON SUN NGT. WITH THIS FEATURE MVG CLOSER TO CWA, CLDS WL
OVRSPRD THE REGION DRG THE DAY SUNDAY WITH SLGTLY COOLER TEMPS
EXPECTED, THO STILL ABV NORMAL.
&&
.AVIATION /23Z TUESDAY THROUGH SUNDAY/...
18Z UPDATE...
IFR CONDITIONS AT KELM AND KBGM TERMINALS THIS AFTERNOON WITH
SIGNIFICANT MOISTURE TRAPPED UNDER LOW-LEVEL INVERSION. AREA OF
LIGHT TO MODERATE RAIN MOVING THROUGH WITH MVFR-IFR RESTRICTIONS.
ONCE THIS RAIN MOVES THROUGH, A BREAK IS EXPECTED WITH POTENTIAL
RETURN TO MVFR BEFORE NEXT SYSTEM ROLLS THROUGH AFTER 04Z. STILL A
LITTLE UNCERTAINTY AS TO HOW MUCH RAIN WILL AFFECT KITH/KELM/KBGM
AND KAVP, THUS HAVE LEFT PCPN MENTION OUT OF THESE TERMINALS AT
THIS TIME. FURTHER NORTH AT KSYR AND KRME HAVE INCLUDED SHOWER
MENTION THROUGH THE END OF THE TAF PERIOD WITH POSSIBLE -TSRA
BETWEEN 03Z AND 07Z.
WINDS AROUND 10KTS OUT OF THE ESE WITH GRADUALLY SHIFT AROUND TO
THE SOUTHWEST BY 12Z BETWEEN 10-15KTS.
OUTLOOK...
WED...MVFR IN SCT SHRA/TSRA.
THU-SAT...MAINLY VFR.
SUN...POTENTIAL FOR MVFR IN SHRA/TSRA AS COLD FRONT APPROACHES.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...HEDEN
NEAR TERM...HEDEN/RRM
SHORT TERM...HEDEN
LONG TERM...PVN
AVIATION...PVN
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
747 PM EDT TUE MAY 28 2013
.SYNOPSIS...
WESTERN ATLANTIC HIGH PRESSURE ANCHORED OFFSHORE FROM THE CAROLINA
COASTS...WILL CONTINUE TO RIDGE BACK ACROSS THE FORECAST AREA FOR
THE REMINDER OF THIS WEEK AND THROUGH THE WEEKEND. THIS WILL
RESULT IN PARTLY TO MOSTLY SUNNY DAYS AND MOSTLY CLEAR NIGHTS...
WITH THE THREAT FOR AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS
INCREASING BY THE END OF THE WEEK AND WEEKEND. TEMPERATURES
THROUGHOUT THE PERIOD WILL REMAIN NEAR NORMAL. THE NEXT COLD FRONT
WILL APPROACH FROM THE WEST LATE MONDAY.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
AS OF 700 PM TUESDAY...DIURNALLY DRIVEN CU ACROSS THE FA DISSIPATING
AT THE MOMENT...AS A RESULT OF THE DAYS INSOLATION COMING TO AN
END. THIS LEAVES ONLY CIRRUS CLOUDINESS TO MOVE OVERHEAD OVERNIGHT
WITH MUCH OF IT ON THE THIN SIDE. HAVE CONTINUED WITH THE
CURRENT CLEAR/MOSTLY CLEAR FORECAST FOR TONIGHT. ACTIVE SEA BREEZE
THIS EVENING SHOULD FINALLY WANE LATE THIS EVENING...WITH SE-S
WINDS DIMINISHING TO 5 MPH OR LESS. THE EXCEPTION WILL BE ALONG
THE IMMEDIATE COAST WHERE ONSHORE FLOW SHOULD KEEP WINDS IN THE 5
TO 10 MPH RANGE OVERNIGHT. MIN TEMPS TONIGHT LOOK ON TARGET WITH
VERY LITTLE TWEAKING NEEDED. LATEST NAMBUFR SOUNDINGS INDICATE THE
SFC BASED INVERSION WILL BE LIMITED IN DEPTH...WITH LIMITED
LOCATIONS TO EXPERIENCE DECOUPLING OF THE WINDS. THERE-FORE...WILL
KEEP ANY FOG DEVELOPMENT ON THE PATCHY SIDE.
PREVIOUS
DISCUSSION........................................................
AS OF 230 PM TUESDAY...IMPRESSIVE WV IMAGERY THIS AFTN PAINTS THE
PICTURE ACROSS THE SOUTHEAST. EXPANSIVE AREA OF CONVECTION DRAPED
FROM NORTHERN MEXICO...INTO IOWA...AND EAST INTO NEW
ENGLAND...BOUNDS THE WESTERN AND NORTHERN PERIPHERY OF AN UPPER
RIDGE CONTROLLING THE SYNOPTIC REGIME OVER THE SOUTHEAST.
WHILE CU HAS BEEN WIDESPREAD THIS AFTN...VERTICAL DEPTH OF THE
CLOUDS IS QUITE LIMITED THANKS TO WEAK FORCING AND INCREASING
CONVECTIVE LID BENEATH BUILDING THERMAL RIDGE ALOFT. HAVE KEPT POP
JUST BELOW THRESHOLD FOR THE REST OF THE DAY. HRRR CONTINUING TO
SUGGEST SOME ISOLATED SHOWERS TODAY...BUT IT CONTINUES TO BE OVER
AGGRESSIVE IN DEVELOPING DEEP CONVECTION SO HAVE IGNORED IT AND
LEANED ON ARW/NAM WHICH KEEP TODAY DRY. CONVECTIVE/DIURNAL CU WILL
SLOWLY ERODE THIS AFTN/EVE...AND ALTHOUGH THERE MAY BE SOME HIGH
LEVEL DEBRIS CLOUDINESS...OVERALL A MOSTLY CLEAR NIGHT IS EXPECTED.
WITH DEWPOINTS SURGING THIS AFTN ON MOIST SE FLOW...CROSSOVER TEMPS
WILL BE APPROACHED TONIGHT. ATTM DO NOT EXPECT THEM TO BE EXCEEDED
HOWEVER...MINS FALLING ONLY INTO THE MID/UPPR 60S...AND THIS COMBINED
WITH 15 KTS OF WIND JUST ABOVE THE NOCTURNAL INVERSION WILL INHIBIT
WIDESPREAD FOG. STILL...HAVE LEFT SOME PATCHY FOG IN THE WX GRIDS
AFTER MIDNIGHT.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
AS OF 230 PM TUESDAY...BUILDING RIDGE ALOFT AND THE ESTABLISHMENT OF
THE BERMUDA HIGH WILL LEAD TO A BENIGN SHORT TERM PERIOD. TEMPS WILL
PRIMARILY BE PERSISTENCE WITH HIGHS IN THE MID/UPPER 80S ACROSS THE
PEE DEE/LBT AREAS AND LOWER 80S COASTAL SECTIONS (NEAR 80 BEACHES)
EACH DAY. MEANWHILE EXPECT LIGHT ONSHORE FLOW TO TO SUPPORT LOWS IN
THE LOWER TO MID 60S EACH NIGHT. COULD SEE PATCHY FLOG EACH
MORNING...WITH POSSIBLY SOME STRATUS FOR A BRIEF PERIOD LATE
THURSDAY NIGHT.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 230 PM TUESDAY...FRIDAY APPEARS TO OFFER A CONVECTIVE MINIMUM
THROUGH THE PERIOD. THE BERMUDA HIGH WILL BE PUMPING WARMTH AND
MOISTURE ACROSS THE REGION BUT UPPER RIDGING MAY HAVE JUST ENOUGH AN
INFLUENCE AT CAPPING ALL BUT ISO COVERAGE. NOT SEEING MUCH EVIDENCE
OF PIEDMONT TROUGH SO IT MAY BE CONFINED TO THE SEA BREEZE. OVER THE
WEEKEND THE UPPER RIDGE MOVES EASTWARD AND RELAXES ITS SUPPRESSING
EFFECTS ON CONVECTION. COVERAGE MAY STILL BE ISOLATED IN THE ABSENCE
OF ANYTHING BUT MESOSCALE FORCING AND SO THE SEA BREEZE SEEMS THE
MOST LIKELY CULPRIT. SHOULD THE APPROACHING UPPER TROUGH BE QUICK
ENOUGH IT MAY SPREAD SW INCREASING WINDS OVER MAINLY WRN ZONES TO
ENHANCE POPS THERE BUT WITH THE ANTECEDENT RIDGE THINK IT/LL BE
SLOWER. IN FACT THE EFFECTS OF THE DOWNSTREAM RIDGE CAN BE SEEN IN
THE WAY GUIDANCE HANDLES THE APPROACH OF THE TROUGH...IT BECOMES
GRADUALLY POSITIVELY TILTED WITH TIME. AS A RESULT INTO NEXT WEEK
THE FRONT IT DRIVES DECELERATES. ITS PROXIMITY TO OUR NW COULD
FUNNEL EXTRA MOISTURE INTO THE CAROLINAS FOR SOME SLIGHTLY HIGHER
COVERAGE OF THUNDERSTORMS EACH AFTERNOON. TRUE TO A WARM SEASON
PATTERN THERE ARE LITTLE DAY TO DAY VARIATIONS IN TEMPERATURES
EITHER FROM ONE ANOTHER OR FROM CLIMO.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
AS OF 00Z...EXPECT VFR THROUGH THE VALID TAF PERIOD WITH THE
EXCEPTION OF PATCHY AREAS OF FOG LATE OVERNIGHT INTO THE EARLY
MORNING HOURS ON WEDNESDAY WHICH COULD CREATE MVFR CONDITIONS.
FEW MID AND HIGH-LEVEL CLOUDS CONTINUE TO LINGER ACROSS THE AREA
THIS EVENING...WITH SOUTH WINDS AOB 10 KTS. INTO THE OVERNIGHT
HOURS...VFR WILL PREVAIL WITH SOUTH-SOUTHWEST WINDS AT THE SFC
BECOMING AOB 5 KTS. ANTICIPATE AREAS OF LIGHT FOG TO
DEVELOP...THOUGH GUIDANCE CONTINUES TO SUGGEST INCREASED BOUNDARY
LAYER WINDS AROUND 15 KTS...WHICH WILL LIKELY INHIBIT ANY
WIDESPREAD FOG. THUS HAVE OPTED TO CONTINUE POSSIBILITY OF FOG
DEVELOPMENT AT INLAND SITES AS WELL AS KCRE. AFTER DAYBREAK...ANY
LINGERING FOG WILL QUICKLY DISSIPATE GIVING WAY TO VFR AREA-WIDE.
ANTICIPATE WINDS TO RANGE FROM SOUTHEAST TO SOUTHWEST WITH
SUSTAINED SPEEDS INCREASING TO AOB 15 KTS BY THE AFTERNOON HOURS
WITH FEW/SCT LOW...MID...AND HIGH-LEVEL CLOUDS.
EXTENDED OUTLOOK...MORNING MVFR/ISOLATED IFR FOG THROUGH SATURDAY.
OTHERWISE VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 715 PM TUESDAY...WESTERN ATLANTIC HIGH PRESSURE CENTERED
OFFSHORE FROM THE CAROLINAS TO RIDGE BACK WSW ACROSS THE AREA
WATERS. THE ACTUAL SFC RIDGE AXIS PLACEMENT ACROSS THE WATERS WILL
DETERMINE WIND DIRECTIONS...IE. SSE-S NORTH OF THE AXIS...AND
SE-SSE SOUTH OF THE AXIS. SFC PG REMAINS ON THE LOOSE SIDE...WITH
SYNOPTIC WINDS AROUND 10 KT. EXCEPTION WILL BE NEAR SHORE THIS
EVENING WHERE THE MESOSCALE INDUCED SEA BREEZE CIRCULATION WILL
PRODUCE A TEMPORARY 10-15 KT WIND SPEED. SIGNIFICANT SEAS WILL RUN
2 FT...AND WILL BE DOMINATED BY THE 2 FOOT 9 SECOND PERIOD ESE
GROUND SWELL...WITH SOLID 3 FOOTERS LURKING JUST EAST OF THE ILM
WATERS. WILL INCLUDE 3 F00T SIG. SEAS ACROSS THE OUTER WATERS OFF
CAPE FEAR. NEAR SHORE...SEA BREEZE WIND CHOP WILL SUBSIDE LATER
THIS EVENING AND OVERNIGHT.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 230 PM TUESDAY...BERMUDA HIGH PRESSURE IN A STAGNANT PATTERN
WILL KEEP THE FLOW OUT OF A SOUTHEAST TO SOUTH DIRECTION THROUGH THE
SHORT TERM PERIOD. THE PRESSURE GRADIENT IS NOT OVERLY IMPRESSIVE
AND SPEEDS WILL BE AROUND 10 KNOTS. GIVEN THE FETCH EXPECT SEAS TO
RANGE FROM 2-3 FT THROUGH THE PERIOD AS WELL.
LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 230 PM TUESDAY...SE FLOW AROUND BERMUDA HIGH PRESSURE ON
FRIDAY WILL VEER SLIGHTLY TO S FOR THE REMAINDER OF THE PERIOD AS
THE HIGHS RIDGE AXIS RETREATS SLIGHTLY OUT TO SEA. OTHER THAN THAT
SMALL VEER THERE SHOULD BE LITTLE VARIATION IN WIND AND/OR SEAS
THROUGH MOST OF THE PERIOD AS THE HIGH REMAINS QUASI-STATIONARY.
SEAS WILL BE IN THE 2 TO 4 FT RANGE WITH THE HIGHEST VALUES LOCATED
OFF THE COAST.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SRP
NEAR TERM...DCH/JDW
SHORT TERM...SRP
LONG TERM...MBB
AVIATION...SGL
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
510 PM CDT MON MAY 27 2013
.UPDATE...
ISSUED AT 508 PM CDT MON MAY 27 2013
A CLUSTER OF SHOWERS HAVE DEVELOPED IN THE PAST 30 MINUTES BETWEEN
GRAND FORKS AND DEVILS LAKE WITH OTHER CELLS INCLUDING THUNDER
AROUND JAMESTOWN. SO UPDATED TO ADD POPS THRU 03Z ACROSS ALL OF NE
ND AND THE NRN VALLEY FOR THIS ACTIVITY. 21Z RAP INDICATES THIS IS
MOSTLY HEAT DRIVEN AND WILL DISSIPATE BY 03Z AS MAIN RAIN AREA
REMAINS IN CNTRL ND. WILL NEED TO WATCH THAT PROGRESSION FOR
FUTURE UPDATES.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 325 PM CDT MON MAY 27 2013
SHORTWAVE LIFTING NE INTO SE MT PROVIDING UPPER SUPPORT FOR STRONG
CONVECTION ACROSS MT/SD/ND BORDER AREA VCNTY SURFACE LOW. MODELS
IN GOOD AGREEMENT IN LIFTING THIS COMPLEX NNE OVERNIGHT. EASTERN
EDGE COULD CLIP WESTERN FA LATER TONIGHT SO WILL MAINTAIN HIGHER
POPS THERE. ANOTHER AREA OF DEVELOPMENT WILL BE ALONG BOUNDARY
FROM S CENTRAL SD INTO IOWA. THIS COMPLEX SHOULD REMAIN SOUTH OF
THE FA SO HAVE TRIMMED BACK ON POPS ACROSS THE SOUTH. FEEL GFS HAS
BEST HANDLE ON CURRENT AND EXPECTED DEWPOINTS SO WILL FOLLOW ITS
GUIDANCE FOR MIN TEMPERATURES.
COULD SEE SOME LINGERING SHRA MAINLY ACROSS THE NORTH TUESDAY AS
WAVE LIFTS INTO CANADA. CLOUDS AGAIN WILL IMPACT TEMPERATURES BUT
COLUMN SLIGHTLY WARMER AND COULD SEE SOME BREAKS IN THE CLOUDS IN
SUBSIDENCE ZONE BEHIND WAVE SO WILL STICK WITH WARMER MAXIMUM
TEMPERATURES.
LOOKS TO BE ANOTHER CONVECTIVE COMPLEX DEVELOPING TUESDAY NIGHT
ACROSS CENTRAL/NORTHERN HIGH PLAINS BUT AT THIS POINT SHOULD
REMAIN SW OF FA. WITH SURFACE DEWPOINTS ON THE INCREASE WILL SEE
WARMER MINIMUM TEMPERATURES.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 325 PM CDT MON MAY 27 2013
WEDNESDAY SHOULD START OUT DRY HOWEVER AS MAIN WAVE BEGINS TO LIFT
NE CENTRAL PLAINS BOUNDARY WILL ALSO LIFT NE AND COULD SEE SOME
CONVECTION WORKING INTO SOUTHERN ZONES BY EVENING. BEST POTENTIAL
FOR SIGNIFICANT RAINFALL WILL BE WEDNESDAY NIGHT AS BOUNDARY LIFTS
THROUGH FA AND UPPER LOW CLOSES OFF. MODELS CONTINUE TO DIFFER ON
FAR NORTH BOUNDARY LIFTS AND WHERE HEAVIEST RAIN WILL FALL.
THURSDAY NIGHT THROUGH MONDAY...PRIMARY CONCERN WILL BE THE
EVOLUTION OF AN ELONGATED TROUGH ALOFT FROM THE PACIFIC NORTHWEST
INTO THE NORTHERN PLAINS. BY 00 UTC SATURDAY...THE VORTICITY MAXIMUM
IS NEAR PIERRE SD WITH THE GEM...THE ND/SD/MN TRI-STATE BORDER
REGION WITH THE GFS AND ALONG THE CANADIAN BORDER NORTH OF MINOT
WITH THE ECMWF. THE DGEX IS MOST SIMILAR TO THE GEM. AT THIS TIME...
THE ECMWF IS AN OUTLIER WHERE AFTER A QUICK SHOT OF PRECIPITATION
THURSDAY NIGHT INTO FRIDAY...IT LIFTS THE RESPONSIBLE WARM FRONT
NORTH OF THE BORDER AND KEEPS THE FORECAST AREA DRY. THE GFS/GEM/
DGEX...HOWEVER...PLACE THE NEARLY STATIONARY WARM FRONT ACROSS THE
FORECAST AREA...RESULTING IN RAINFALL ACCUMULATIONS GREATER THAN ONE
INCH. WILL LEAN TOWARD SIMILAR WETTER SOLUTIONS AT THIS TIME...WHICH
MATCHES WELL WITH ALL BLEND 40 TO 60 POPS THURSDAY NIGHT THROUGH
FRIDAY. THE ECMWF WRAP-AROUND PRECIPITATION IS ALSO FARTHER SOUTH
AND SLOWER THAN THE OTHER MODELS...BUT IT LOOKS LIKE A RETURN TO
DRIER CONDITIONS SATURDAY AND ESPECIALLY SATURDAY NIGHT INTO SUNDAY.
ANOTHER PACIFIC WAVE WILL RESULT IN ADDITIONAL RAIN CHANCES EARLY
NEXT WEEK. THE SYSTEM/S COLD FRONT WILL SWEEP ACROSS THE FORECAST
AREA ON FRIDAY...RESULTING IN COOLER TEMPERATURES FOR THE WEEKEND
WITH HIGHS IN THE 60S AND LOWS IN THE 40S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1220 PM CDT MON MAY 27 2013
MVFR/LOW VFR CEILINGS WILL PERSIST AT ALL TAF SITES THROUGH 18 UTC
TUESDAY. OVERNIGHT...COULD SEE SOME IFR CONDITIONS AT KDVL/KBJI.
WINDS WILL BE FROM THE SOUTHEAST AROUND 10 TO 15 KTS. SOME
SPRINKLES/LIGHT RAIN SHOWERS ARE POSSIBLE AT KDVL/KFAR AFTER 00
UTC...BUT NOT LIKELY ENOUGH TO INCLUDE IN CURRENT TAFS.
&&
.HYDROLOGY...
ISSUED AT 320 PM CDT MON MAY 27 2013
ALL RIVER FLOOD WARNINGS HAVE BEEN CANCELLED. THE RED RIVER IS
CRESTING JUST BELOW MINOR FLOOD STAGE AT PEMBINA AND IS BEGINNING TO
SLOWLY FALL FROM A CREST RIGHT AT MINOR FLOOD STAGE AT
DRAYTON...WHILE THE BUFFALO RIVER NEAR DILWORTH HAS FALLEN BELOW
FLOOD STAGE. AREA RIVERS WILL CONTINUE TO FALL OR REMAIN STEADY OVER
THE NEXT FEW DAYS.
AN AREAL FLOOD WARNING REMAINS IN EFFECT FOR PEMBINA...WALSH...AND
EASTERN CAVALIER COUNTIES THROUGH TUESDAY. WITH NO APPRECIABLE RAIN
OVER THE PAST FEW DAYS...WATER LEVELS ACROSS THIS AREA SHOULD
CONTINUE TO GRADUALLY DECREASE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...RIDDLE
SHORT TERM...VOELKER
LONG TERM...ROGERS/VOELKER
AVIATION...ROGERS
HYDROLOGY...MAKOWSKI
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
933 AM CDT MON MAY 27 2013
.UPDATE...
ISSUED AT 930 AM CDT MON MAY 27 2013
MINIMAL CHANGES FOR THIS UPDATE. LIGHT SHOWERS ACROSS N CENTRAL ND
CONTINUE TO WEAKEN AND NOT LIKELY TO REACH FAR NW FA. OTHER
SHOWERS CONTINUE ACROSS NW-N CENTRAL SD HOWEVER NOT CONFIDENT
ENOUGH THAT THEY WILL HOLD TOGETHER SO WILL MAINTAIN DRY FORECAST
FOR NOW. CLOUDS COVER ALL BUT FAR NE FA AND WITH LOW CONVECTIVE
TEMPERATURES AND MOIST LAYER AOB 3-4K FT FEEL ANY SOLAR WILL BE
VERY LIMITED. THIS WILL RESULT IN TEMPERATURES SIMILAR TO YSTDY SO
CURRENT MAX VALUES SEEM GOOD.
UPDATE ISSUED AT 650 AM CDT MON MAY 27 2013
WATCHING A BAND OF SHOWERS/THUNDER ACROSS WESTERN NORTH DAKOTA
SLOWLY PROPAGATE TO THE EAST. THIS ACTIVITY WOULD MOVE INTO THE
WESTERN FA AROUND 15Z-16Z AT ITS CURRENT PACE. THE RESPONSIBLE
UPPER WAVE IS PROPAGATING TO THE NORTHEAST...AND STILL EXPECT THIS
ACTIVITY TO WEAKEN. IF THEY HOLD TOGETHER...THE NEXT UPDATE CAN
TAKE CARE OF THIS. THE LAST FEW HRRR RUNS ARE INITIATING SHOWERS
WITHIN THE FA AROUND 15Z-17Z...POSSIBLY ASSOCIATED WITH AN UPPER
WAVE CURRENTLY PRODUCING SHOWERS ACROSS NORTHWEST SOUTH DAKOTA.
WILL STICK WITH THE DRY FORECAST AND MONITOR...IT SEEMS UNLIKELY
THAT ANY MEASURABLE PRECIP WILL OCCUR GIVEN THE STABLE AIRMASS
(ALTHOUGH WOULD NOT DOUBT SOME SPRINKLES). NOT MUCH HAS CHANGED
WITH THE THINKING REGARDING CLOUDS AND MAX TEMPS FOR TODAY...THE
NEXT UPDATE SHOULD HAVE A MUCH BETTER IDEA WITH HOW THE LOW CLOUDS
WILL BEHAVE.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 345 AM CDT MON MAY 27 2013
THE CHALLENGE WILL BE SHOWER/THUNDER CHANCES AND TIMING/PLACEMENT
OF SHORTWAVES IN SOUTHWEST FLOW ALOFT. THE MODELS ALL INDICATE THE
SAME GENERAL SOLUTION...BUT DIFFER GREATLY WITH WHERE THEY
INITIATE AND PROPAGATE CONVECTIVE COMPLEXES. THE ECMWF...AND
ESPECIALLY THE GEM...HAVE VERIFIED THE BEST OVER THE PAST COUPLE
DAYS...AND WILL FOLLOW FOR DETAILS.
FOR TODAY...THERE ARE TWO SHORTWAVES AND ASSOCIATED CONVECTIVE
COMPLEXES THAT COULD AFFECT THE FA. ONE IS ENTERING IOWA...AND
PROPAGATING SOUTHEAST...AND WILL REMAIN WELL TO THE SOUTH. THE
SECOND IS ACROSS WESTERN NORTH DAKOTA. THE STRONGEST FORCING FROM
THIS SHORTWAVE WILL CONTINUE PROPAGATING TO THE NORTHEAST...AND
SHOULD MISS THE FA. THE AIRMASS REMAINS STABLE AS LOW LEVEL
SOUTHEAST FLOW CONTINUES...AND EXPECT ANYTHING THAT APPROACHES THE
FA TO FALL APART (MUCH LIKE YESTERDAY). SO...WENT WITH A DRY
FORECAST FOR TODAY (THERE COULD BE SPRINKLES OR AN ISOLATED
SHOWER...BUT NOT MUCH MORE THAN THAT).
CLOUDS HAVE DEVELOPED ACROSS THE ENTIRE FA AS 925MB WINDS ARE NOW
SOUTHERLY...AS OPPOSED TO SOUTHEAST. MODELS INDICATE 925MB WINDS
BECOMING MORE SOUTHEAST BY THE AFTERNOON...AND ADVECTING A DRIER
LOW LEVEL AIRMASS INTO PARTS OF THE EASTERN FA. MAX TEMPS WILL BE
SIMILAR TO YESTERDAY...LOW TO MID 60S UNDER LOW CLOUDS...AND LOW
TO MID 70S WHERE PARTLY CLOUDY. FOLLOWED THE RAP FOR PLACEMENT OF
CLOUDS AND ASSOCIATED TEMPERATURES...WHICH WILL LIKELY NEED TO BE
ADJUSTED A BIT (VERY SIMILAR TO YESTERDAY).
TONIGHT-TUESDAY...A SIMILAR SITUATION SHOULD PLAY OUT FOR THIS
PERIOD AS TO WHAT IS OCCURRING TONIGHT. ANTICIPATE TWO CONVECTIVE
COMPLEXES TO INITIATE THIS EVENING...WITH ONE ACROSS THE WESTERN
DAKOTAS AND THE OTHER ACROSS CENTRAL/EASTERN SOUTH DAKOTA (THE
ASSOCIATED SHORTWAVES CAN EASILY BEEN SEEN UPSTREAM ON WATER VAPOR
IMAGERY). THESE COMPLEXES COULD BRUSH THE NW AND SE FA...ALTHOUGH
INSTABILITY REMAINS WEAK WITHIN THIS FA. THE ECMWF IS MUCH
FURTHER NORTH AND BULLISH WITH THE SOUTHERN COMPLEX...BUT WILL
DISCOUNT AS IT HAD A SIMILAR BIAS WITH THE CURRENT ACTIVITY. KEPT
THE CHANCE POPS ACROSS THE FAR WESTERN AND SOUTHERN FA...AND
REMOVED THE THUNDER CHANCES FOR THE REMAINDER OF THE FA (THE
AMERICAN MODELS HAVE HAD A WET BIAS AND ANY DISSIPATING SHOWERS
WILL NOT HAVE AN IMPACT). WEAK RIDING EXPECTED BY TUESDAY
AFTERNOON AND EXPECT SUNSHINE AND WARMER TEMPERATURES.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 345 AM CDT MON MAY 27 2013
TUESDAY NIGHT-WEDNESDAY NIGHT...
WEAK RIDING TO START THIS PERIOD WITH UPPER FLOW BECOMING MORE
SOUTHERLY BY WEDNESDAY AFTERNOON/EVENING. THIS SHOULD LEAD TO DRY
WEATHER INTO MUCH OF WEDNESDAY AFTERNOON...WITH THUNDER CHANCES
INCREASING LATER WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT. SEVERE
POTENTIAL WILL DEPEND ON HOW QUICKLY THE HIGHER LOW LEVEL MOISTURE
AND THE WARM FRONT CAN ADVECT NORTHWARD. THE GEM/NAM ARE FURTHER
NORTH WITH THIS FEATURE THAN THE GFS/ECMWF BY LATE WEDNESDAY
AFTERNOON. SPC KEEPS THE HIGHER SEVERE PROBABILITIES SOUTH OF THE
FA (LINING UP WITH THE GFS/ECMWF). USUALLY...THE WARM FRONT DOES
STAY SOUTH...WE SHALL SEE. AS FORCING INCREASES WEDNESDAY
NIGHT...INSTABILITY SHOULD BE WEAKER AND THE SEVERE THREAT
DEPENDENT OF THE STRENGTH OF THE LOW LEVEL JET (ANTICIPATE A FEW
STRONGER STORMS).
THURSDAY-SUNDAY...
MODELS REMAIN FAIRLY CONSISTENT WITH CLOSING OFF AN UPPER LOW
OVER MONTANA BY THURSDAY FROM THE 500MB SOUTHWEST FLOW. AS A
RESULT STRONG WAA ON THURSDAY ACROSS THE CWFA MAY BRING A SOUTH TO
NORTH CONVECTIVE COMPLEX THROUGH THE AREA. KEPT THE LIKELY POPS
INTO THE AFTERNOON THURSDAY. BY 00Z FRI THE ECMWF AND GEM BOTH
CENTER THE UPPER LOW IN E MT OR W ND WHEREAS THE GFS BRINGS IT
FARTHER TO THE SE OVER NC SD WITH THE SFC LOW NEAR BIS. THE ECMWF
AND GEM SOLN WOULD BRING THE DRY SLOT ACROSS THE AREA FRI AND SAT
COMPARED TO THE MORE CONVECTIVE AND WETTER GFS WHICH KEEPS WARM
FRONTAL BOUNDARY DRAPED ACROSS THE CWFA. BY SUNDAY THE WAVE IS
PUSHED EAST WITH SHOWERS ENDING. HI TEMPS TO BE HIGHLY DEPENDENT
ON CLOUD COVER FRI AND SAT...WARMER IN THE DRY SLOT AND COOLER IF
GFS VERIFIES...70S VS 60S. SEASONABLY COOL ON SUNDAY IN THE WAKE
OF THE SYSTEM WITH HIGHS IN 60S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 650 AM CDT MON MAY 27 2013
IFR/MVFR CIGS ACROSS CENTRAL NORTH DAKOTA GRADUALLY BECOME MVFR
ACROSS EASTERN NORTH DAKOTA...AND THEN VFR EAST OF THE RED RIVER
VALLEY. LOW LEVEL FLOW CHANGES VERY LITTLE THROUGH THE DAY...AND
EXPECT LITTLE CHANGE TO CIGS AS A RESULT (ALTHOUGH THEY MAY LIFT
FOR A FEW HOURS THIS AFTERNOON).
&&
.HYDROLOGY...
ISSUED AT 118 PM CDT SUN MAY 26 2013
ALL TRIBUTARIES TO THE RED RIVER ARE FALLING ACROSS THE FORECAST
AREA. THE BUFFALO RIVER AT DILWORTH HAS APPARENTLY CRESTED AND WILL
FALL SLOWLY DURING THIS WEEK. ON THE MAIN STEM OF THE RED RIVER...
THE RIVER IS STEADY OR FALLING IN THE SOUTHERN PART OF THE VALLEY.
IT IS STILL SLOWLY RISING OVER THE NORTHERN VALLEY AT PEMBINA...AND
NEAR CREST AT DRAYTON. OSLO CRESTED EARLIER TODAY AT AROUND MINOR
FLOOD STAGE OF 26 FEET.
RIVER FLOOD WARNINGS REMAIN IN EFFECT AT JUST THREE LOCATIONS...
PEMBINA AND DRAYTON ON THE RED AND DILWORTH ON THE BUFFALO.
AREAL FLOOD WARNINGS REMAIN IN EFFECT FOR PEMBINA...WALSH...AND
EASTERN CAVALIER COUNTIES THROUGH TUESDAY. WATER LEVELS ACROSS THIS
AREA SHOULD GRADUALLY DECREASE OVER THE NEXT FEW DAYS WITH MODEST
ADDITIONAL RAINFALL ANTICIPATED.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...VOELKER
SHORT TERM...TG
LONG TERM...TG/JK
AVIATION...TG
HYDROLOGY...WJB
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
650 AM CDT MON MAY 27 2013
.UPDATE...
ISSUED AT 650 AM CDT MON MAY 27 2013
WATCHING A BAND OF SHOWERS/THUNDER ACROSS WESTERN NORTH DAKOTA
SLOWLY PROPAGATE TO THE EAST. THIS ACTIVITY WOULD MOVE INTO THE
WESTERN FA AROUND 15Z-16Z AT ITS CURRENT PACE. THE RESPONSIBLE
UPPER WAVE IS PROPAGATING TO THE NORTHEAST...AND STILL EXPECT THIS
ACTIVITY TO WEAKEN. IF THEY HOLD TOGETHER...THE NEXT UPDATE CAN
TAKE CARE OF THIS. THE LAST FEW HRRR RUNS ARE INITIATING SHOWERS
WITHIN THE FA AROUND 15Z-17Z...POSSIBLY ASSOCIATED WITH AN UPPER
WAVE CURRENTLY PRODUCING SHOWERS ACROSS NORTHWEST SOUTH DAKOTA.
WILL STICK WITH THE DRY FORECAST AND MONITOR...IT SEEMS UNLIKELY
THAT ANY MEASURABLE PRECIP WILL OCCUR GIVEN THE STABLE AIRMASS
(ALTHOUGH WOULD NOT DOUBT SOME SPRINKLES). NOT MUCH HAS CHANGED
WITH THE THINKING REGARDING CLOUDS AND MAX TEMPS FOR TODAY...THE
NEXT UPDATE SHOULD HAVE A MUCH BETTER IDEA WITH HOW THE LOW CLOUDS
WILL BEHAVE.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 345 AM CDT MON MAY 27 2013
THE CHALLENGE WILL BE SHOWER/THUNDER CHANCES AND TIMING/PLACEMENT
OF SHORTWAVES IN SOUTHWEST FLOW ALOFT. THE MODELS ALL INDICATE THE
SAME GENERAL SOLUTION...BUT DIFFER GREATLY WITH WHERE THEY
INITIATE AND PROPAGATE CONVECTIVE COMPLEXES. THE ECMWF...AND
ESPECIALLY THE GEM...HAVE VERIFIED THE BEST OVER THE PAST COUPLE
DAYS...AND WILL FOLLOW FOR DETAILS.
FOR TODAY...THERE ARE TWO SHORTWAVES AND ASSOCIATED CONVECTIVE
COMPLEXES THAT COULD AFFECT THE FA. ONE IS ENTERING IOWA...AND
PROPAGATING SOUTHEAST...AND WILL REMAIN WELL TO THE SOUTH. THE
SECOND IS ACROSS WESTERN NORTH DAKOTA. THE STRONGEST FORCING FROM
THIS SHORTWAVE WILL CONTINUE PROPAGATING TO THE NORTHEAST...AND
SHOULD MISS THE FA. THE AIRMASS REMAINS STABLE AS LOW LEVEL
SOUTHEAST FLOW CONTINUES...AND EXPECT ANYTHING THAT APPROACHES THE
FA TO FALL APART (MUCH LIKE YESTERDAY). SO...WENT WITH A DRY
FORECAST FOR TODAY (THERE COULD BE SPRINKLES OR AN ISOLATED
SHOWER...BUT NOT MUCH MORE THAN THAT).
CLOUDS HAVE DEVELOPED ACROSS THE ENTIRE FA AS 925MB WINDS ARE NOW
SOUTHERLY...AS OPPOSED TO SOUTHEAST. MODELS INDICATE 925MB WINDS
BECOMING MORE SOUTHEAST BY THE AFTERNOON...AND ADVECTING A DRIER
LOW LEVEL AIRMASS INTO PARTS OF THE EASTERN FA. MAX TEMPS WILL BE
SIMILAR TO YESTERDAY...LOW TO MID 60S UNDER LOW CLOUDS...AND LOW
TO MID 70S WHERE PARTLY CLOUDY. FOLLOWED THE RAP FOR PLACEMENT OF
CLOUDS AND ASSOCIATED TEMPERATURES...WHICH WILL LIKELY NEED TO BE
ADJUSTED A BIT (VERY SIMILAR TO YESTERDAY).
TONIGHT-TUESDAY...A SIMILAR SITUATION SHOULD PLAY OUT FOR THIS
PERIOD AS TO WHAT IS OCCURRING TONIGHT. ANTICIPATE TWO CONVECTIVE
COMPLEXES TO INITIATE THIS EVENING...WITH ONE ACROSS THE WESTERN
DAKOTAS AND THE OTHER ACROSS CENTRAL/EASTERN SOUTH DAKOTA (THE
ASSOCIATED SHORTWAVES CAN EASILY BEEN SEEN UPSTREAM ON WATER VAPOR
IMAGERY). THESE COMPLEXES COULD BRUSH THE NW AND SE FA...ALTHOUGH
INSTABILITY REMAINS WEAK WITHIN THIS FA. THE ECMWF IS MUCH
FURTHER NORTH AND BULLISH WITH THE SOUTHERN COMPLEX...BUT WILL
DISCOUNT AS IT HAD A SIMILAR BIAS WITH THE CURRENT ACTIVITY. KEPT
THE CHANCE POPS ACROSS THE FAR WESTERN AND SOUTHERN FA...AND
REMOVED THE THUNDER CHANCES FOR THE REMAINDER OF THE FA (THE
AMERICAN MODELS HAVE HAD A WET BIAS AND ANY DISSIPATING SHOWERS
WILL NOT HAVE AN IMPACT). WEAK RIDING EXPECTED BY TUESDAY
AFTERNOON AND EXPECT SUNSHINE AND WARMER TEMPERATURES.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 345 AM CDT MON MAY 27 2013
TUESDAY NIGHT-WEDNESDAY NIGHT...
WEAK RIDING TO START THIS PERIOD WITH UPPER FLOW BECOMING MORE
SOUTHERLY BY WEDNESDAY AFTERNOON/EVENING. THIS SHOULD LEAD TO DRY
WEATHER INTO MUCH OF WEDNESDAY AFTERNOON...WITH THUNDER CHANCES
INCREASING LATER WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT. SEVERE
POTENTIAL WILL DEPEND ON HOW QUICKLY THE HIGHER LOW LEVEL MOISTURE
AND THE WARM FRONT CAN ADVECT NORTHWARD. THE GEM/NAM ARE FURTHER
NORTH WITH THIS FEATURE THAN THE GFS/ECMWF BY LATE WEDNESDAY
AFTERNOON. SPC KEEPS THE HIGHER SEVERE PROBABILITIES SOUTH OF THE
FA (LINING UP WITH THE GFS/ECMWF). USUALLY...THE WARM FRONT DOES
STAY SOUTH...WE SHALL SEE. AS FORCING INCREASES WEDNESDAY
NIGHT...INSTABILITY SHOULD BE WEAKER AND THE SEVERE THREAT
DEPENDENT OF THE STRENGTH OF THE LOW LEVEL JET (ANTICIPATE A FEW
STRONGER STORMS).
THURSDAY-SUNDAY...
MODELS REMAIN FAIRLY CONSISTENT WITH CLOSING OFF AN UPPER LOW
OVER MONTANA BY THURSDAY FROM THE 500MB SOUTHWEST FLOW. AS A
RESULT STRONG WAA ON THURSDAY ACROSS THE CWFA MAY BRING A SOUTH TO
NORTH CONVECTIVE COMPLEX THROUGH THE AREA. KEPT THE LIKELY POPS
INTO THE AFTERNOON THURSDAY. BY 00Z FRI THE ECMWF AND GEM BOTH
CENTER THE UPPER LOW IN E MT OR W ND WHEREAS THE GFS BRINGS IT
FARTHER TO THE SE OVER NC SD WITH THE SFC LOW NEAR BIS. THE ECMWF
AND GEM SOLN WOULD BRING THE DRY SLOT ACROSS THE AREA FRI AND SAT
COMPARED TO THE MORE CONVECTIVE AND WETTER GFS WHICH KEEPS WARM
FRONTAL BOUNDARY DRAPED ACROSS THE CWFA. BY SUNDAY THE WAVE IS
PUSHED EAST WITH SHOWERS ENDING. HI TEMPS TO BE HIGHLY DEPENDENT
ON CLOUD COVER FRI AND SAT...WARMER IN THE DRY SLOT AND COOLER IF
GFS VERIFIES...70S VS 60S. SEASONABLY COOL ON SUNDAY IN THE WAKE
OF THE SYSTEM WITH HIGHS IN 60S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 650 AM CDT MON MAY 27 2013
IFR/MVFR CIGS ACROSS CENTRAL NORTH DAKOTA GRADUALLY BECOME MVFR
ACROSS EASTERN NORTH DAKOTA...AND THEN VFR EAST OF THE RED RIVER
VALLEY. LOW LEVEL FLOW CHANGES VERY LITTLE THROUGH THE DAY...AND
EXPECT LITTLE CHANGE TO CIGS AS A RESULT (ALTHOUGH THEY MAY LIFT
FOR A FEW HOURS THIS AFTERNOON).
&&
.HYDROLOGY...
ISSUED AT 118 PM CDT SUN MAY 26 2013
ALL TRIBUTARIES TO THE RED RIVER ARE FALLING ACROSS THE FORECAST
AREA. THE BUFFALO RIVER AT DILWORTH HAS APPARENTLY CRESTED AND WILL
FALL SLOWLY DURING THIS WEEK. ON THE MAIN STEM OF THE RED RIVER...
THE RIVER IS STEADY OR FALLING IN THE SOUTHERN PART OF THE VALLEY.
IT IS STILL SLOWLY RISING OVER THE NORTHERN VALLEY AT PEMBINA...AND
NEAR CREST AT DRAYTON. OSLO CRESTED EARLIER TODAY AT AROUND MINOR
FLOOD STAGE OF 26 FEET.
RIVER FLOOD WARNINGS REMAIN IN EFFECT AT JUST THREE LOCATIONS...
PEMBINA AND DRAYTON ON THE RED AND DILWORTH ON THE BUFFALO.
AREAL FLOOD WARNINGS REMAIN IN EFFECT FOR PEMBINA...WALSH...AND
EASTERN CAVALIER COUNTIES THROUGH TUESDAY. WATER LEVELS ACROSS THIS
AREA SHOULD GRADUALLY DECREASE OVER THE NEXT FEW DAYS WITH MODEST
ADDITIONAL RAINFALL ANTICIPATED.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...TG
SHORT TERM...TG
LONG TERM...TG/JK
AVIATION...TG
HYDROLOGY...WJB
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
345 AM CDT MON MAY 27 2013
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 345 AM CDT MON MAY 27 2013
THE CHALLENGE WILL BE SHOWER/THUNDER CHANCES AND TIMING/PLACEMENT
OF SHORTWAVES IN SOUTHWEST FLOW ALOFT. THE MODELS ALL INDICATE THE
SAME GENERAL SOLUTION...BUT DIFFER GREATLY WITH WHERE THEY
INITIATE AND PROPAGATE CONVECTIVE COMPLEXES. THE ECMWF...AND
ESPECIALLY THE GEM...HAVE VERIFIED THE BEST OVER THE PAST COUPLE
DAYS...AND WILL FOLLOW FOR DETAILS.
FOR TODAY...THERE ARE TWO SHORTWAVES AND ASSOCIATED CONVECTIVE
COMPLEXES THAT COULD AFFECT THE FA. ONE IS ENTERING IOWA...AND
PROPAGATING SOUTHEAST...AND WILL REMAIN WELL TO THE SOUTH. THE
SECOND IS ACROSS WESTERN NORTH DAKOTA. THE STRONGEST FORCING FROM
THIS SHORTWAVE WILL CONTINUE PROPAGATING TO THE NORTHEAST...AND
SHOULD MISS THE FA. THE AIRMASS REMAINS STABLE AS LOW LEVEL
SOUTHEAST FLOW CONTINUES...AND EXPECT ANYTHING THAT APPROACHES THE
FA TO FALL APART (MUCH LIKE YESTERDAY). SO...WENT WITH A DRY
FORECAST FOR TODAY (THERE COULD BE SPRINKLES OR AN ISOLATED
SHOWER...BUT NOT MUCH MORE THAN THAT).
CLOUDS HAVE DEVELOPED ACROSS THE ENTIRE FA AS 925MB WINDS ARE NOW
SOUTHERLY...AS OPPOSED TO SOUTHEAST. MODELS INDICATE 925MB WINDS
BECOMING MORE SOUTHEAST BY THE AFTERNOON...AND ADVECTING A DRIER
AIRMASS INTO PARTS OF THE EASTERN FA. MAX TEMPS WILL BE SIMILAR TO
YESTERDAY...LOW TO MID 60S WHERE CLOUDY...AND LOW TO MID 70S WHERE
PARTLY CLOUDY. FOLLOWED THE RAP FOR PLACEMENT OF CLOUDS AND
ASSOCIATED TEMPERATURES...WHICH WILL LIKELY NEED TO BE ADJUSTED A
BIT (VERY SIMILAR TO YESTERDAY).
TONIGHT-TUESDAY...A SIMILAR SITUATION SHOULD PLAY OUT FOR THIS
PERIOD AS TO WHAT IS OCCURRING TONIGHT. ANTICIPATE TWO CONVECTIVE
COMPLEXES TO INITIATE THIS EVENING...WITH ONE ACROSS THE WESTERN
DAKOTAS AND THE OTHER ACROSS CENTRAL/EASTERN SOUTH DAKOTA (THE
ASSOCIATED SHORTWAVES CAN EASILY BEEN SEEN UPSTREAM ON WATER VAPOR
IMAGERY). THESE COMPLEXES COULD BRUSH THE NW AND SE FA...ALTHOUGH
INSTABILITY REMAINS WEAK WITHIN THIS FA. THE ECMWF IS MUCH
FURTHER NORTH AND BULLISH WITH THE SOUTHERN COMPLEX...BUT WILL
DISCOUNT AS IT HAD A SIMILAR BIAS WITH THE CURRENT ACTIVITY. KEPT
THE CHANCE POPS ACROSS THE FAR WESTERN AND SOUTHERN FA...AND
REMOVED THE THUNDER CHANCES FOR THE REMAINDER OF THE FA (THE
AMERICAN MODELS HAVE HAD A WET BIAS AND ANY DISSIPATING SHOWERS
WILL NOT HAVE AN IMPACT). WEAK RIDING EXPECTED BY TUESDAY
AFTERNOON AND EXPECT SUNSHINE AND WARMER TEMPERATURES.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 345 AM CDT MON MAY 27 2013
TUESDAY NIGHT-WEDNESDAY NIGHT...
WEAK RIDING TO START THIS PERIOD WITH UPPER FLOW BECOMING MORE
SOUTHERLY BY WEDNESDAY AFTERNOON/EVENING. THIS SHOULD LEAD TO DRY
WEATHER INTO MUCH OF WEDNESDAY AFTERNOON...WITH THUNDER CHANCES
INCREASING LATER WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT. SEVERE
POTENTIAL WILL DEPEND ON HOW QUICKLY THE HIGHER LOW LEVEL MOISTURE
AND THE WARM FRONT CAN ADVECT NORTHWARD. THE GEM/NAM ARE FURTHER
NORTH WITH THIS FEATURE THAN THE GFS/ECMWF BY LATE WEDNESDAY
AFTERNOON. SPC KEEPS THE HIGHER SEVERE PROBABILITIES SOUTH OF THE
FA (LINING UP WITH THE GFS/ECMWF). USUALLY...THE WARM FRONT DOES
STAY SOUTH...WE SHALL SEE. AS FORCING INCREASES WEDNESDAY
NIGHT...INSTABILITY SHOULD BE WEAKER AND THE SEVERE THREAT
DEPENDENT OF THE STRENGTH OF THE LOW LEVEL JET (ANTICIPATE A FEW
STRONGER STORMS).
THURSDAY-SUNDAY...
MODELS REMAIN FAIRLY CONSISTENT WITH CLOSING OFF AN UPPER LOW
OVER MONTANA BY THURSDAY FROM THE 500MB SOUTHWEST FLOW. AS A
RESULT STRONG WAA ON THURSDAY ACROSS THE CWFA MAY BRING A SOUTH TO
NORTH CONVECTIVE COMPLEX THROUGH THE AREA. KEPT THE LIKELY POPS
INTO THE AFTERNOON THURSDAY. BY 00Z FRI THE ECMWF AND GEM BOTH
CENTER THE UPPER LOW IN E MT OR W ND WHEREAS THE GFS BRINGS IT
FARTHER TO THE SE OVER NC SD WITH THE SFC LOW NEAR BIS. THE ECMWF
AND GEM SOLN WOULD BRING THE DRY SLOT ACROSS THE AREA FRI AND SAT
COMPARED TO THE MORE CONVECTIVE AND WETTER GFS WHICH KEEPS WARM
FRONTAL BOUNDARY DRAPED ACROSS THE CWFA. BY SUNDAY THE WAVE IS
PUSHED EAST WITH SHOWERS ENDING. HI TEMPS TO BE HIGHLY DEPENDENT
ON CLOUD COVER FRI AND SAT...WARMER IN THE DRY SLOT AND COOLER IF
GFS VERIFIES...70S VS 60S. SEASONABLY COOL ON SUNDAY IN THE WAKE
OF THE SYSTEM WITH HIGHS IN 60S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1130 PM CDT SUN MAY 26 2013
EXPECT A SLOW LOWERING OF CIGS INTO THE MVFR RANGE FROM WEST TO
EAST THROUGH TONIGHT. CAN/T RULE OUT SOME IFR POCKETS MAINLY ALONG
AND WEST OF THE RED RIVER VALLEY...BUT FOR NOW WILL JUST MENTION
MVFR CONDITIONS AND MONITOR CONDITIONS. SE WINDS WILL CONTINUE AND
GUST TO AROUND 20KT ON TUE AS CLOUDS CONTINUE ALTHOUGH WON/T
MENTION ANY CONVECTION AT THIS TIME...BUT CHANCES FOR SHOWERS AND
STORMS SHOULD INCREASE AT ALL AREAS NEAR THE END OF THIS TAF PERIOD.
&&
.HYDROLOGY...
ISSUED AT 118 PM CDT SUN MAY 26 2013
ALL TRIBUTARIES TO THE RED RIVER ARE FALLING ACROSS THE FORECAST
AREA. THE BUFFALO RIVER AT DILWORTH HAS APPARENTLY CRESTED AND WILL
FALL SLOWLY DURING THIS WEEK. ON THE MAIN STEM OF THE RED RIVER...
THE RIVER IS STEADY OR FALLING IN THE SOUTHERN PART OF THE VALLEY.
IT IS STILL SLOWLY RISING OVER THE NORTHERN VALLEY AT PEMBINA...AND
NEAR CREST AT DRAYTON. OSLO CRESTED EARLIER TODAY AT AROUND MINOR
FLOOD STAGE OF 26 FEET.
RIVER FLOOD WARNINGS REMAIN IN EFFECT AT JUST THREE LOCATIONS...
PEMBINA AND DRAYTON ON THE RED AND DILWORTH ON THE BUFFALO.
AREAL FLOOD WARNINGS REMAIN IN EFFECT FOR PEMBINA...WALSH...AND
EASTERN CAVALIER COUNTIES THROUGH TUESDAY. WATER LEVELS ACROSS THIS
AREA SHOULD GRADUALLY DECREASE OVER THE NEXT FEW DAYS WITH MODEST
ADDITIONAL RAINFALL ANTICIPATED.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...TG
LONG TERM...TG/JK
AVIATION...DK
HYDROLOGY...WJB
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1253 AM CDT MON MAY 27 2013
.UPDATE...
ISSUED AT 1245 AM CDT MON MAY 27 2013
IN COLLABORATION WITH NEIGHBORS HAVE DECIDED TO DROP POPS EAST AND
LOWER THEM SIGNIFICANTLY CENTRAL NORTH DAKOTA FOR THE OVERNIGHT. A
LINE OF THUNDERSTORMS THROUGH EASTERN MONTANA WAS APPROACHING THE
NORTH DAKOTA BORDER AND SO KEPT HIGH POPS THERE. THE STORMS WERE
MOVING INTO LESS UNSTABLE AIR AND SHOULD NOT BE SEVERE. WILL
LIKELY ISSUE A STATEMENT ON THEM FOR SMALL HAIL AND GUSTS WINDS AND
TIME THEM ACROSS THE STATE LINE FOR DECISION SUPPORT SERVICES.
UPDATE ISSUED AT 958 PM CDT SUN MAY 26 2013
UPDATE TO DELAY THUNDERSTORMS EVEN MORE FROM THE EARLY EVENING
UPDATE...BASED ON EVENING HIGH RESOLUTION MODEL TRENDS. STORMS
STILL EXPECTED TO SPREAD INTO WESTERN COUNTIES OVERNIGHT. THERE
MAY BE A FEW STRONG TO MARGINALLY SEVERE STORMS...BUT RELATIVELY
WEAK DEEP LAYER SHEAR IS EXPECTED TO LIMIT POTENTIAL FOR MORE
SIGNIFICANT SEVERE WEATHER. RELATIVELY SLOW STORM MOTIONS WOULD
FAVOR POTENTIAL FOR ISOLATED HEAVY RAINFALL AMOUNTS. STILL SOME
UNCERTAINTY AS TO HOW FAR EAST STORMS WILL SPREAD TOWARD DAYBREAK
AND INTO THE MORNING HOURS MONDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 320 PM CDT SUN MAY 26 2013
FORECAST PROBLEM IN THE SHORT TERM WILL BE THUNDERSTORM CHANCES
THROUGH THE PERIOD. OVERALL MODEL TREND HAS BEEN TO LESSEN OR PUSH
BACK PRECIPITATION CHANCES ESPECIALLY LATE THIS AFTERNOON AND THIS
EVENING. BEYOND THIS THERE IS LITTLE FORECAST CONFIDENCE REGARDING
PRECIPITATION TIMING AND PLACEMENT AS MODELS ARE HAVING A HARD TIME
RESOLVING THIS IN THE BROAD SOUTHWEST UPPER FLOW.
CURRENTLY...MVFR-IFR STRATUS REMAIN ACROSS THE SOURIS TO JAMES
RIVER BASINS...WHILE STRATUS HAS DISSIPATED BUT WELL DEVELOPED CU
FIELD HAS BROKEN OUT OVER THE WEST AND SOUTH CENTRAL. THIS HAS
RESULTED IN TEMPERATURES PUSHING INTO THE LOW TO MID 70S WITH MID
50S DEW POINT TEMPERATURES FROM WESTERN NORTH DAKOTA INTO EASTERN
MONTANA AND NORTHWEST SOUTH DAKOTA. CURRENT SPC ANALYSIS IS
SHOWING CAPES OF 1000-1500 J/KG WITH DIMINISHING CIHN OVER THE
MONDAK REGION WITH INCREASING LAPSE RATES. CONVECTION HAS RECENTLY
INITIATED OVER THE BIGHORNS AND BLACK HILLS. GGW 18Z SOUNDING AND
CURRENT LAPS SOUNDING NEAR KOLF INDICATE A NEAR COMPLETE ERODED
CAP OVER EASTERN MONTANA. LATEST WATER VAPOR SATELLITE IMAGERY
SHOW AN APPROACHING SHORTWAVE TROUGH LIFTING NORTHEAST THROUGH
WYOMING WHICH SHOULD HELP TO INITIATE CONVECTION AWAY FROM THE
MOUNTAINS. WITH THIS SAID...MODELS ARE NOT POINTING TO STRONG
CONVECTION OVER WESTERN AND CENTRAL NORTH DAKOTA THIS AFTERNOON
AND EARLY EVENING. GFS/ECMWF BRING BEST CHANCES INTO THE FAR WEST
LATE TONIGHT WITH CONVECTION CONTINUING EAST ACROSS THE AREA ON
MONDAY. 12 UTC NAM AND 17 UTC HRRR BRING CONVECTION FIRING OFF THE
BIGHORNS INTO SOUTHEAST MONTANA BUT THEN SUPPRESS REFLECTIVITIES
AS THEY MOVE INTO WESTERN NORTH DAKOTA. 12 UTC HIRES ARW/NMM EAST
BOTH POINT MORE TOWARD LATE NIGHT CONVECTION MOVING INTO THE WEST
AND LINGERING INTO MONDAY...WITH YET ANOTHER ROUND OF CONVECTION
ON MONDAY.
FOR NOW WILL LEAN TOWARD SLIGHT CHANCE POPS EAST TO CHANCE POPS
WEST THIS EVENING...THEN INCREASING AFTER MIDNIGHT WITH HIGHEST
POPS REMAINING IN THE WEST. THEN BASICALLY A BROAD BRUSH OF HIGH
CHANCE POPS ON MONDAY DUE TO SO MUCH UNCERTAINTY ON
TIMING/PLACEMENT. WITH AFOREMENTIONED SEVERE WEATHER INGREDIENTS
WILL KEEP A MENTION OF SEVERE LATE THIS AFTERNOON AND THIS
EVENING. IF CONVECTION WOULD DEVELOP AND MOVE INTO WESTERN NORTH
DAKOTA...THE GREATEST THREAT WOULD LIKELY BE LARGE HAIL AND VERY
HEAVY RAIN CAUSING LOCALIZED FLOODING PROBLEMS.
ALTHOUGH SPC SLIGHT RISK DOES INCLUDE A PORTION OF THE FAR
SOUTHWEST ON MONDAY...WILL HOLD OFF ON MENTIONING THIS IN THE
FORECAST FOR NOW. WILL LET LATER SHIFTS RE-EVALUATE.
MODELS DO INDICATE INCREASING 925MB MOISTURE TONIGHT. CONSIDERED
ADDING A MENTION OF FOG...BUT THINK THE BIGGEST ISSUE WILL BE LOW
STRATUS AND LIFR CEILINGS. COULD SEE SOME MVFR VISIBILITIES BUT
WILL HOLD OFF ON ADDING FOG FOR NOW.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 320 PM CDT SUN MAY 26 2013
A VERY ACTIVE WEATHER PATTERN WILL PERSIST ACROSS THE NORTHERN
PLAINS THROUGH MUCH IF NOT ALL OF THE EXTENDED PERIOD.
LONG WAVE TROUGH WEST AND RIDGING EAST WILL MAINTAIN SOUTHWESTERLY
FLOW ALOFT ACROSS THE DAKOTAS MONDAY NIGHT. SHOWERS AND POSSIBLY
SEVERE THUNDERSTORMS WILL BE ONGOING AT THE START OF THE PERIOD
MONDAY EVENING AS A STRONG S/WV LIFTS NORTHEAST THROUGH THE REGION.
SCALED BACK PRECIPITATION CHANCES TUESDAY/TUESDAY EVENING AS A S/WV
RIDGE ADVANCES NORTHEAST THROUGH THE STATE ALONG WITH DRIER AIR INTO
MY WEST. SHOWER/THUNDERSTORM CHANCES INCREASE TUESDAY NIGHT AS THE
RIDGE CONTINUES OFF TO OUR NORTH AND EAST RESULTING IN FLOW ALOFT
TRANSITIONING TO SOUTHWEST ONCE AGAIN...WITH A LEAD IMPULSE MOVING
NORTH THROUGH THE WESTERN DAKOTAS.
BY WEDNESDAY MORNING THE BASE OF THE WESTERN CONUS TROUGH WILL BE
OVER THE SOUTHERN ROCKIES...WHICH IS DEPICTED BY BOTH THE 12Z
GFS/ECMWF TO SWING NORTH THROUGH THE CENTRAL PLAINS INTO THE DAKOTAS
WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT. FOR THURSDAY...THE BASE OF
THE TROUGH MORPHS INTO A CUTOFF LOW WHICH MAY LINGER ACROSS THE
NORTHERN PLAINS INTO SATURDAY IF THE 12Z ECMWF VERIFIES. THE 12Z GFS
IS MORE PROGRESSIVE...WITH THE LOW BECOMING AN OPEN WAVE AND MOVING
OVER THE WESTERN GREAT LAKES REGION BY SATURDAY MORNING. BOTH MODEL
SOLUTIONS RESULT IN HIGH CHANCES FOR SHOWERS AND THUNDERSTORMS
WEDNESDAY-WEDNESDAY NIGHT-THURSDAY...WITH A CHANCE OF STRONG TO
SEVERE STORMS AS WELL. FORECAST UNCERTAINTY INCREASES AFTER WARDS FOR
FRIDAY THROUGH THE WEEKEND WITH THE ABOVE MENTIONED DIFFERENCES
BETWEEN THE GFS/ECMWF.
TEMPERATURES WILL AVERAGE NEAR TO SLIGHTLY ABOVE NORMAL EARLY NEXT
WEEK...THEN WILL AVERAGE NEAR TO SLIGHTLY BELOW NORMAL FOR THE END
OF THE WORK WEEK THROUGH NEXT WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1240 AM CDT MON MAY 27 2013
A LINE OF THUNDERSTORMS THROUGH EASTERN MONTANA WAS PUSHING EAST
WHILE INDIVIDUAL CELLS WERE PUSHING NORTHEAST. THIS LINE WILL BE
INTO NORTHWEST NORTH DAKOTA...KISN...AROUND 27/07Z. THE SOUTHERN
END OF THE LINE WAS WEAKENING AND MAY NOT MAKE IT TO KDIK IN TACT.
OTHERWISE...MOIST SOUTHEAST FLOW CONTINUES THROUGH THE FORECAST
PERIOD KEEPING MVFR / IFR CEILINGS IN THE FORECAST FOR THE TAF SITES.
PATCHY FOG WAS FOUND AROUND THE AREA AND THERE IS A REFLECTION OF
THAT IN THE 27/06Z TAF ISSUANCE.
BEHIND THE THUNDERSTORMS...LATER MONDAY...STEADIER LIGHT RAIN IS
FORECAST WEST.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JPM
SHORT TERM...TWH
LONG TERM...NH
AVIATION...JPM
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
638 PM CDT TUE MAY 28 2013
.UPDATE...
NO MAJOR CHANGES TO THE GOING FORECAST THIS EVENING. THUNDERSTORMS
ARE CURRENTLY MOVING OVER THE BLACK HILLS AND WILL CONTINUE TO
PROGRESS NORTHEAST THIS EVENING. POPS AND WX MAY BE AN HOUR OR TWO
FAST BUT APPEAR TO BE IN DECENT SHAPE BASED ON CURRENT RADAR TRENDS.
SEE UPDATED AVIATION DISCUSSION BELOW.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT
THE MODELS ARE IN GOOD AGREEMENT THROUGH THE SHORT TERM WITH THE
MAIN WEATHER FEATURES. A LARGE NEGATIVELY TILTED UPPER LEVEL LOW
PRESSURE TROUGH OVER THE SOUTHWEST US STILL SET TO KICK OUT INTO
THE NORTHERN PLAINS WEDNESDAY THROUGH THURSDAY AND CLOSING OFF
ACROSS OUR REGION. FOR TONIGHT...AN INITIAL WAVE WILL EJECT OUT
TONIGHT INTO OUR REGION BRINGING AN MCS ACROSS MAINLY THE SOUTHERN
CWA THIS EVENING AND OVERNIGHT. THE HRRR AND WRF MODELS BOTH SHOW
AN MCS MOVING ACROSS SOUTHERN SD TONIGHT. FOR MUCH OF THE EASTERN
CWA...IT WILL BE DRY THROUGH MUCH OF THE NIGHT. WITH CLEARING
SKIES AND WINDS BECOMING LIGHT TONIGHT...EXPECT SOME MORE FOG TO
FORM FROM THE JAMES VALLEY AND EAST TONIGHT AND REMAIN INTO
WEDNESDAY MORNING. THE MODELS ALSO SHOW A GOOD LLJ ALONG WITH GOOD
LOW AND MID LEVEL WAA DEVELOPING THROUGH THE NIGHT AND WEDNESDAY
MORNING. THIS WILL AID IN NUMEROUS SHOWER AND THUNDERSTORM
DEVELOPMENT LATER TONIGHT AND WEDNESDAY. BROAD SCALE UPPER LEVEL
DIVERGENCE WITH THE UPPER TROUGH WILL CONTINUE TO PROVIDE GOOD
ASCENT INTO WEDNESDAY NIGHT AND THURSDAY MORNING ACROSS THE CWA.
THE MODELS ALL SHOW A GOOD SURFACE LOW PRESSURE AREA IN EASTERN
COLORADO LIFTING NORTHEAST INTO NORTH DAKOTA WEDNESDAY AFTERNOON
INTO THURSDAY EVENING AND DEEPENING.
EVERYTHING IS SET FOR SOME SEVERE WEATHER POSSIBILITIES AND HEAVY
RAIN DEVELOPMENT WEDNESDAY AND WEDNESDAY NIGHT. THE THING THAT MAY
HOLD OFF MORE WIDESPREAD SEVERE WEATHER DEVELOPMENT WILL BE EARLY
SHOWER AND THUNDERSTORM DEVELOPMENT ACROSS THE CWA AND CLOUD COVER
THROUGH THE DAY AND EVENING WEDNESDAY. THIS WILL HOLD BACK THE
DEVELOPMENT OF HIGH INSTABILITY. NONETHELESS...DEEP LAYER
SHEAR...MOISTURE AND INSTABILITY WILL BE THERE FOR SOME SEVERE
STORMS ALONG WITH HEAVY RAINFALL. MADE SOME CALLS IN THE HEAVY
RAIN AREAS TODAY AND IT SEEMS MOST OF THE RAINFALL OVER THE LAST
SEVERAL DAYS HAD SOAKED IN PRETTY GOOD. HAVE INCREASED CHANCES OF
RAINFALL ACROSS THE REGION THROUGH WEDNESDAY NIGHT ALONG WITH
ADDING IN THE MENTION OF HEAVY RAIN AND SEVERE WEATHER
POSSIBILITIES. MUCH OF THE RAINFALL MAY END THURSDAY MORNING IN
THE EASTERN CWA AS THE DRY LINE/COLD FRONT SWINGS IN QUICKLY
THROUGH THE DAY BEHIND THE SURFACE LOW PRESSURE AREA. IN FACT...IT
MAY BECOME WINDY ACROSS THE CWA THURSDAY AFTERNOON AND EVENING
WITH A STRONG SURFACE LOW PRESSURE AREA TO THE NORTH ALONG WITH
GOOD MIXING. LOWERED POPS FOR THURSDAY NIGHT ACROSS THE CWA.
.LONG TERM...FRIDAY THROUGH TUESDAY
THE PERIOD BEGINS WITH A LARGE UPPER LEVEL LOW PRESSURE SYSTEM
SITUATED OVER THE NORTHERN PLAINS. THIS SYSTEM WILL BRING PERIODS
OF SHOWERS AND PERHAPS A THUNDERSTORM OR TWO DURING THE AFTERNOON
HOURS ON FRIDAY. CAPE VALUES ARE REDUCED SIGNIFICANTLY BY FRIDAY
NIGHT SO WILL ONLY MENTION SHOWERS THROUGH THE WEEKEND. DEPENDING
ON THE PLACEMENT OF THE LOW PRESSURE...HIGH TEMPERATURES ON
SATURDAY COULD BE PRETTY CHILLY. THE 12Z RUN OF THE ECMWF IS
SUGGESTING 925MB TEMPERATURES WILL ONLY WARM INTO THE MID/UPPER
SINGLE DIGITS. THANKFULLY THE GFS/GEM DEPICT SLIGHTLY WARMER LOW
LEVEL TEMPERATURES. OVERALL SATURDAY WILL BE CHILLY WITH HIGHS
ONLY IN THE UPPER 50S...TO THE MID 60S EXPECTED. SUNDAY WILL MARK
THE BEGINNING OF A WARMING TREND WITH TEMPERATURES FINALLY
REACHING ABOVE NORMAL BY MONDAY.
CHANCES FOR THUNDERSTORMS WILL RETURN TO THE FORECAST BY MONDAY
NIGHT. A SURFACE LOW PRESSURE AND COLD FRONT SLIDING ACROSS THE
REGION WILL BE THE FOCUS MECHANISM FOR CONVECTION.
&&
.AVIATION...
00Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
PRIMARILY VFR CONDITIONS ARE EXPECTED THROUGH MOST OF THE NIGHT.
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE BETWEEN 02-06Z FOR
KPIR. CONDITIONS MAY FALL TO MVFR RANGE UNDER STRONGER STORMS.
AS SHOWERS AND THUNDERSTORMS DEVELOP AND SPREAD OVER THE AREA
WEDNESDAY MORNING AND AFTERNOON MVFR CIGS WILL BEGIN TO AFFECT THE
TAF SITES. VSBY MAY ALSO FALL TO MVFR/IFR IN HEAVIER SHOWERS ON
WEDNESDAY.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...WISE
SHORT TERM...MOHR
LONG TERM...SD
AVIATION...WISE
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
920 PM CDT TUE MAY 28 2013
.DISCUSSION...DID NOT MESS WITH MINIMUM TEMPERATURES...BUT DID
ADJUST DEW POINTS AND HOURLY TEMPERATURES BASED ON CURRENT OBS AND
TRENDS. ALSO...DID KEEP 20 POPS FOR THE EXTREME NORTHWEST...AS 4
KM HRRR MODEL IS SHOWING ACTIVITY CREEPING TOWARD AREA ALBEIT
WEAKER. LAPS ANALYSIS IS SHOWING INCREASING CAP/CIN DEVELOPING OUT
WEST...BUT GOOD SOUTHEAST WINDS AT SURFACE AND NEAR SURFACE MAY
ALLOW SOME OF THIS ACTIVITY TO CREEP INTO THE AREA AFTER MIDNIGHT.
INCREASED WINDS JUST A BIT OVER INLAND AREAS AS WELL. REST OF
FORECAST IS FINE FOR NOW.
&&
.MARINE...DECIDED TO EXTEND THE SCA FOR THE BAYS TIL 4 AM...WHICH
MAY BE A TAD LONG BUT BELIEVE SUSTAINED WINDS WILL CONTINUE TO BE
NEAR SCA AND GUST WILL GENERALLY EXCEED THOSE VALUES SINCE UPPER
LOW WILL LIKELY DEEPEN SURFACE PRESSURE WHICH WILL KEEP GRADIENT
TIGHT ENOUGH. KEPT SCA FOR GULFMEX AS-IS FOR NOW...BUT WILL LIKELY
NEED TO BE EXTENDED BY MID SHIFT FOR AT LEAST WINDS.
&&
.PREV DISCUSSION... /ISSUED 647 PM CDT TUE MAY 28 2013/
DISCUSSION...UPDATED FOR THE 00Z AVIATION DISCUSSION.
AVIATION...STRONG SE WINDS GUSTING UP TO 35 KTS WILL BEGIN TO
DECOUPLE SLIGHTLY THIS EVENING OVER ALI-CRP-VCT...HOWEVER ARE
EXPECTED TO REMAIN PAST 06Z FOR LRD AS THE LLJ DEVELOPS. ELEVATED
WINDS OVERNIGHT WILL PRECLUDE THE MENTION OF LLWS IN THE TAFS.
MVFR CIGS BEGINNING TO DEVELOP ALONG THE COAST...WITH ALL SITES
AT MVFR AFTER 06Z WITH HEIGHTS AROUND 2K FEET. MODELS WERE HINTING
AT DEVELOPMENT OF THUNDERSTORMS OUT WEST MOVING S-SE AFFECTING
LRD BTWN 03Z-06Z...HOWEVER AM THINKING INSTABILITY WILL BE LESS
WITH THE BEST UPPER DYNAMICS REMAINING WELL TO THE NORTH...WHICH
SHOULD INHIBIT DEVELOPMENT IN SOUTH TEXAS. WILL MONITOR TRENDS.
WINDS WILL AGAIN INCREASE MID-DAY WEDNESDAY...WITH CIGS
TRANSITIONING TO VFR. THE STRONGEST WINDS SHOULD REMAIN AROUND
ALI-CRP...GUSTING UP TO 35KT.
PREV DISCUSSION... /ISSUED 342 PM CDT TUE MAY 28 2013/
SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)...CHANCES FOR
SHOWERS AND THUNDERSTORMS WILL BE THE MAIN CONCERN IN THE SHORT
TERM. WEAKNESS IN FLOW ALOFT JUST NORTHEAST OF THE CWA COMBINED
WITH DAYTIME HEATING HAS RESULTED IN A FEW SHOWERS THIS AFTERNOON
MAINLY EAST OF INTERSTATE 37. MUCH LIKE YESTERDAY...EXPECT THIS
ACTIVITY TO DIMINISH WITH LOSS OF DAYTIME HEATING. HAVE INSERTED A
10 POP WITH MENTION OF SHOWERS THROUGH 00Z TO ACCOUNT FOR THESE
SHOWERS. ATTENTION WILL TURN OUT TO THE WEST LATER THIS EVENING
WHERE LOWER CONFIDENCE OF CONVECTION EXISTS. SHORT TERM GUIDANCE
KEEPS MOST OF THE CONVECTION NORTHWEST OF THE REGION AND OVER
MEXICO. HIGH RES MODELS ALSO SHOW MIXED SIGNALS WRT TO
THUNDERSTORMS OUT WEST. 4KM WRF NMM ORGANIZES LINE OF CONVECTION
ON THE DRYLINE LATER THIS EVENING. STRONG SSE LOW LEVEL JET OF 40
TO 45 KNOTS DEVELOPS THIS EVENING OVER THE AREA SO IT IS POSSIBLE
COMPLEX COULD MAKE IT INTO THE WESTERN ZONES. DESPITE LOWER
CONFIDENCE OF THIS OCCURRING... INCLUDED A 20 POP ACROSS THE
WESTERN PART OF WEBB AND LASALLE COUNTIES. WILL MONITOR CONVECTIVE
TRENDS THROUGH THE EVENING. ANOTHER ROUND OF STRATUS TONIGHT LOOKS
LIKELY AS SOUTHEAST WINDS REMAIN UP...SO WARM TEMPS OVERNIGHT LOWS
ARE EXPECTED IN THE MIDDLE TO UPPER 70S.
POTENT UPPER LEVEL TROUGH MOVES OUT OF THE FOUR CORNERS INTO THE
HIGH PLAINS ON WEDNESDAY. WINDS WILL BE BREEZY TO WINDY DUE TO
STRONG GRADIENT B/W SFC TROUGH OVER THE PLAINS AND HIGH PRESSURE TO
THE EAST. NOT CONFIDENT ON ADVISORY LEVEL WINDS AND WILL DEFER TO
NEXT SHIFT. MODELS PROG MOISTURE TO INCREASE ACROSS SOUTH TEXAS
TOMORROW WITH PW VALUES CLIMBING BETWEEN 1.7 AND 1.9 INCHES. MODELS
DIFFER ON THE AMOUNT OF INSTABILITY WITH THE NAM REMAINING GREATER
WITH MLCAPES AOA 3000 J/KG. WITH SUFFICIENT DYNAMICS PRESENT AS
SHORTWAVE APPROACHES...A STRONG TO POSSIBLY SEVERE STORM THREAT MAY
MATERIALIZE DURING THE AFTERNOON. HAVE RETAINED THE 20 AND 30 POPS
ACROSS THE AREA FOR TOMORROW. AT OR ABOVE NORMAL TEMPS WILL
PERSIST ON WEDNESDAY WITH MID 90S IN THE WEST TO NEAR 90 IN THE
EAST.
MARINE...SMALL CRAFT ADVISORY CONDITIONS WILL CONTINUE OVER THE
BAYS THROUGH THE EARLY EVENING AND OVER THE OPEN GULF WATERS
THROUGH AT LEAST 12Z WEDNESDAY AS A PERSISTENT STRONG ONSHORE FLOW
CONTINUES.
LONG TERM (THURSDAY THROUGH TUESDAY)...MODELS PROG UPPER LEVEL
RIDGE TO BLD ACROSS THE REGION FROM THE W ON THU. THIS WILL LEAD TO
A VERY WARM DAY...ESPECIALLY ACROSS THE W CWA WHERE 700MB TEMPS WILL
BE 13C AND 850MB TEMPS 22C. PRECIP NOT EXPECTED DUE TO THE VERY WARM
MID LEVEL TEMPS AND LIMITED MOISTURE. THE UPPER LEVEL RIDGE IS PRGD
TO FLATTEN OUT FRI/SAT...BUT OVERALL CONDITIONS WILL BE PERSISTENT.
PRECIP CHCS INCREASE ON SUNDAY AS AN UPPER SHORT WAVE TRACKS ACROSS
S TX AND COMBINES WITH DEEPER MOISTURE. MID LEVEL TEMPS ARE ALSO
PROGD TO COOL RESULTING IN A WEAKENING CAP. KEPT A SLIGHT CHC ACROSS
MUCH OF THE CWA BUT ALSO INCREASED POPS TO 30 PERCENT ACROSS THE NE
DUE TO PROXIMITY TO DEEPER MOISTURE AND WEAKEST CAP. MODELS DO NOT
SHOW A LOW LEVEL FOCUS OR BDRY...AND WEAK UPPER LEVEL JET WILL BE
FAR REMOVED FROM S TX...THEREFORE AM NOT EXPECTING SVR AT THIS TIME.
THE LATEST MODEL RUNS PROG THE UPPER SHORT WAVE TO EXIT THE REGION
BY MONDAY BUT GIVEN INCONSISTENCIES FROM RUN TO RUN...KEPT THE
SLIGHT CHC FOR MON.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 78 91 79 93 78 / 10 30 10 10 10
VICTORIA 75 88 75 88 76 / 10 30 20 10 10
LAREDO 78 97 79 99 79 / 10 20 20 10 10
ALICE 77 91 77 93 76 / 10 30 20 10 10
ROCKPORT 79 84 79 83 79 / 10 30 10 10 10
COTULLA 75 94 76 96 75 / 20 30 20 10 10
KINGSVILLE 77 91 78 92 78 / 10 30 20 10 10
NAVY CORPUS 79 83 79 85 79 / 10 30 10 10 10
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 8 AM CDT WEDNESDAY FOR THE FOLLOWING
ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS OUT
20 NM...COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA SHIP
CHANNEL OUT 20 NM...WATERS FROM BAFFIN BAY TO PORT ARANSAS
FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS TO MATAGORDA
SHIP CHANNEL FROM 20 TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 4 AM CDT WEDNESDAY FOR THE FOLLOWING
ZONES: BAYS AND WATERWAYS FROM BAFFIN BAY TO PORT ARANSAS...
BAYS AND WATERWAYS FROM PORT ARANSAS TO PORT O`CONNOR.
&&
$$
GW/86...SHORT TERM
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1141 PM CDT SUN MAY 26 2013
.DISCUSSION...
LOOK FOR STRATUS TO RETURN TO WEST CENTRAL TEXAS WITHIN THE NEXT
SEVERAL HOURS. SEE THE BELOW AVIATION.
&&
.AVIATION...
MODELS THIS CYCLE DELAY THE STRATUS ONSET ACROSS OUR SOUTHERN
COUNTIES FOR A FEW MORE HOURS. THE LATEST IR IMAGERY SUPPORTS
THIS PREDICTION...WITH ONLY A SMALL PATCH OF STRATUS CURRENTLY
DEVELOPING SOUTH OF OUR COUNTIES. THUS...I BELIEVE A TIMING OF
EITHER 07Z OR 08Z LOOKS BEST THIS CYCLE FOR MVFR CEILINGS FOR OUR
SOUTHERN THREE TERMINALS. THE RUC 925 MB RELATIVE HUMIDITY FIELD
STILL INCREASES TO SATURATION AS FAR NORTH AS SAN ANGELO BY 12Z.
HOWEVER...GIVEN WHAT I CURRENTLY OBSERVE ON IR IMAGERY...MY
CONFIDENCE IS LOW FOR MVFR CEILINGS AT SAN ANGELO. SO...I WILL
LIKELY MAINTAIN VFR FORECASTS FOR THE NEXT 24 HOURS FOR THE
ABILENE AND SAN ANGELO TERMINALS. AGAIN...SURFACE WINDS TOMORROW
WILL BE FROM THE SOUTH AND GUSTY.
HUBER
&&
.PREV DISCUSSION... /ISSUED 900 PM CDT SUN MAY 26 2013/
UPDATE...
FORECAST IS BEING UPDATED MAINLY FOR POPS AND SKY CONDITION...SEE
DISCUSSION.
DISCUSSION...
ISOLATED THUNDERSTORMS HAVE DEVELOPED THIS EVENING IN THE TEXAS
PANHANDLE SOUTHEAST OF AMARILLO...AND NEAR FORT STOCKTON. WITH
THE ABSENCE OF OTHER CONVECTIVE DEVELOPMENT TO OUR WEST...NOT
EXPECTING SHOWERS AND STORMS TO ENTER OUR AREA TONIGHT. HAVE
REMOVED THE POPS AND DECREASED THE CLOUD COVERAGE PER RECENT TRENDS
IN SATELLITE IMAGERY. WITH MOISTENING SOUTHEASTERLY BOUNDARY LAYER
FLOW OVERNIGHT...EXPECT LOW CLOUD DEVELOPMENT ACROSS OUR
SOUTHEASTERN COUNTIES TOWARD MORNING. THE LOW CLOUD FIELD SHOULD
ERODE MID TO LATE MORNING ON MONDAY...WITH A DIURNAL CUMULUS FIELD
IN THE AFTERNOON. MINOR ADJUSTMENTS WERE ALSO MADE TO TEMPERATURE
AND DEWPOINT GRIDS TO BRING IN LINE WITH SURFACE OBSERVATIONS THIS
EVENING. UPDATED FORECAST PRODUCTS WILL BE OUT SHORTLY.
PREV DISCUSSION... /ISSUED 631 PM CDT SUN MAY 26 2013/
DISCUSSION...
LOOK FOR STRATUS TO BRING MVFR CEILINGS BACK TO MUCH OF WEST
CENTRAL TEXAS LATER TONIGHT. PLEASE SEE THE BELOW AVIATION
SECTION FOR MORE INFORMATION.
AVIATION...
THE LATEST RUC 925 MB RELATIVE HUMIDITY FIELD INDICATES STRATUS
WILL DOMINATE MUCH OF WEST CENTRAL TEXAS SOUTH OF INTERSTATE 20 BY
06Z TONIGHT. FOR NOW...I DECIDED TO CONTINUE WITH VFR CONDITIONS
AT SAN ANGELO...AS WELL AS ABILENE...FOR THE NEXT 24 HOURS. BY 18Z
TOMORROW...EXPECT VFR CONDITIONS TO AGAIN DOMINATE WEST CENTRAL TEXAS.
AS FOR SURFACE WINDS TOMORROW...MODELS INDICATE A SURFACE TROUGH
ACROSS WEST TEXAS WILL CREATE A MODERATE SURFACE PRESSURE GRADIENT
ACROSS WEST CENTRAL TEXAS. THUS...WATCH FOR GUSTY SOUTHERLY
SURFACE WINDS TO DOMINATE WEST CENTRAL TEXAS TOMORROW...ESPECIALLY
DURING THE AFTERNOON HOURS.
HUBER
PREV DISCUSSION... /ISSUED 327 PM CDT SUN MAY 26 2013/
SHORT TERM...
SIMILAR SCENARIO IN OUR WESTERN COUNTIES EXPECTED THIS EVENING AS
OCCURRED LAST EVENING WITH 0-6KM SHEAR OF 25-30KT AND MLCAPES OF
1500-2000 J/KG. DRYLINE WILL STRETCH FROM THE BIG BEND THROUGH THE
PERMIAN BASIN LATE THIS AFTERNOON WITH THUNDERSTORMS EXPECTED TO
DEVELOP ONCE AGAIN ALONG THE DRYLINE DURING TIME OF MAX HEATING.
ANY STORMS THAT DO DEVELOP MAY ONCE AGAIN IMPACT OUR WESTERN
COUNTIES BUT SHOULD BE IN A WEAKENING PHASE DUE TO THE LOSS OF
DIURNAL HEATING BY THE TIME THEY ENTER OUR COUNTIES. AT THIS TIME
DO NOT EXPECT ANY STORMS TO ENDURE PAST MIDNIGHT...SO SHOULD NOT
HAVE ANY STORMS PROPAGATING THROUGH THE CWA AS WE HAD LAST NIGHT.
LOOKING FOR CONTINUED WARMING WITH AFTERNOON HIGHS TOMORROW A FEW
DEGREES WARMER THAN TODAY...LOW TO MID 90S. MORNING LOWS SHOULD
ALSO BE A LITTLE WARMER...IN THE UPPER 60S TO AROUND 70.
15
LONG TERM...
THE WEST COAST TROUGH WILL DEEPEN EARLY NEXT WEEK AS A STRONG WAVE
MOVES INTO THE PACNW...AMPLIFYING THE SYNOPTIC PATTERN AS THE
MID LEVEL RIDGE BUILDS OVER THE EAST CONUS. PRONOUNCED SOUTHWEST
FLOW ALOFT WILL MAINTAIN/INTENSIFY THE MID LEVEL CAPPING INVERSION
THROUGH TUESDAY. THE MONDAY/TUESDAY DAYTIME PERIODS LOOK TO BE
BREEZY...WARM AND DRY /FOR THE MOST PART/ WITH TEMPERATURES
WARMING INTO THE LOWER 90S. A FEW DIURNAL THUNDERSTORMS ARE
EXPECTED TO FIRE EACH AFTERNOON IN THE VICINITY OF THE DRYLINE TO
THE WEST AND MAY MAKE A RUN FOR OUR WESTERN COUNTIES. THE CAP IS
STRONG BUT IF THE STRONG INSTABILITY IS TAPPED...SOME STORMS MAY
HAVE THE POTENTIAL TO BECOME SEVERE. HOWEVER...MOST AREAS WILL
REMAIN DRY.
ON WEDNESDAY...THE MODELS APPEAR TO BE CONVERGING ON A SOLUTION
THAT IS A COMPROMISE BETWEEN THE PREVIOUS RUNS OF THE GFS AND
ECMWF. THIS NEW SOLUTION DEPICTS A NEGATIVELY TILTED SHORTWAVE
TROUGH EJECTING INTO THE PLAINS BY PEAK HEATING ON WEDNESDAY.
SYNOPTIC SCALE ASCENT WILL WORK ON THE CAPPING INVERSION
THROUGHOUT THE DAY AND IS EXPECTED TO COOL MID LEVEL TEMPS
SUFFICIENTLY FOR THE CAP TO BREAK BY THURSDAY AFTERNOON. THERE IS
SOME HINT THAT WE COULD SEE ONGOING CONVECTION EARLY WEDNESDAY BUT
THIS SHOULD WEAKEN THROUGHOUT THE DAY AS MID LEVEL WARM ADVECTION
WANES. SLIGHTLY COOLER TEMPS ARE EXPECTED WITH HIGHS GENERALLY IN
THE MID/UPPER 80S. FORMIDABLE DEEP LAYER SHEAR /0-6KM BULK SHEAR
OF 35-40 KTS/ AND STRONG SURFACE BASED INSTABILITY WILL HEIGHTEN
THE POTENTIAL FOR SEVERE CONVECTION...WITH LARGE HAIL AND DAMAGING
WINDS BEING THE PRIMARY THREATS. ANY STORMS THAT DEVELOP WILL
PERSIST INTO THE EVENING HOURS.
BY THURSDAY...THIS WAVE WILL BE EAST OF THE AREA WITH A MORE
SUBSIDENT REGIME ANTICIPATED DURING THE DAY. IF ANY STORMS DO
DEVELOP...I THINK COVERAGE WILL BE VERY LIMITED. THUS...NO
MENTIONABLE POPS WERE CARRIED FOR THURSDAY AND THURSDAY NIGHT.
TEMPS WILL REBOUND TO NEAR NORMAL VALUES WITH HIGHS GENERALLY IN
THE UPPER 80S TO LOWER 90S. THIS TREND WILL CONTINUE ON FRIDAY
WITH TEMPS AT OR ABOVE 90 DEGREES IN MOST LOCATIONS WITH THE BEST
CHANCE FOR AFTERNOON AND EVENING STORMS FOUND TO THE NORTH AND
WEST OF THE CWA.
THE MODELS DISAGREE WITH THE PATTERN FOR THIS WEEKEND. THE GFS
CONTINUES TO SHOW A WEAK COLD FRONT MOVING SOUTH INTO WEST CENTRAL
TX WITH INCREASING RAIN CHANCES WHILE THE ECMWF KEEPS THIS FRONT
TO THE NORTH OF THE AREA. GIVEN THE LACK OF CONFIDENCE IN EITHER
SOLUTION...I USED A GFS/ECMWF BLEND FOR THE WEEKEND. I DID INCLUDE
A SLIGHT CHANCE FOR THUNDERSTORMS ACROSS THE BIG COUNTRY ON
SATURDAY AFTERNOON BUT THIS IS CONDITIONAL ON THE GFS SOLUTION OF
A COLD FRONT IN THE VICINITY COMING TO FRUITION.
JOHNSON
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 70 92 68 90 70 / 10 10 10 5 20
SAN ANGELO 70 92 71 92 71 / 10 5 10 5 20
JUNCTION 69 91 71 90 72 / 10 5 5 5 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
HUBER
AREA FORECAST DISCUSSION
NWS AMARILLO TX
1125 PM CDT SUN MAY 26 2013
.AVIATION...
THE COMBINATION OF A DRYLINE TO THE EAST OF THE THREE TAF SITES ALONG
WITH A SOUTHWESTERLY FLOW ALOFT WILL CAUSE CONVECTION TO ONCE AGAIN
DEVELOP MONDAY AFTERNOON AND EVENING. THIS CONVECTION WILL REMAIN
WELL EAST OF THE AMARILLO TAF SITE. VFR CONDITIONS WILL PREVAIL
THROUGH THE TAF FORECAST PERIOD. SOUTHERLY TO SOUTHWESTERLY WINDS 15
TO 25 KNOTS WITH HIGHER GUSTS WILL BE THE RULE...HOWEVER WINDS WILL
DIMINISH TO AROUND 10 TO 15 KNOTS TONIGHT UNTIL AROUND 15Z MONDAY AT
BOTH THE GUYMON AND DALHART TAF SITES...AND THEN DIMINISH AGAIN AFTER
01Z TUESDAY.
SCHNEIDER
&&
.PREV DISCUSSION... /ISSUED 1040 PM CDT SUN MAY 26 2013/
UPDATE...
HAVE UPDATED GRAPHICAL FORECASTS...NOW LIMITING SCATTERED EVENING
THUNDERSTORMS TO COLLINGSWORTH COUNTY IN SOUTHEAST CORNER OF TEXAS
PANHANDLE ONLY. UPDATED TEXT PRODUCTS WILL BE ISSUED SHORTLY.
COCKRELL
PREV DISCUSSION... /ISSUED 856 PM CDT SUN MAY 26 2013/
UPDATE...
HAVE UPDATED GRAPHICAL FORECASTS...REDUCING COVERAGE/POPS FOR EVENING
THUNDERSTORMS. HAVE CONFINED SCATTERED THUNDERSTORMS TO SOUTHEAST
TEXAS PANHANDLE...AND HAVE TRIMMED ISOLATED TO A SMALLER PORTION OF
EASTERN PARTS OF FORECAST AREA.
WILL ALLOW RED FLAG WARNING TO EXPIRE AT 9 PM.
UPDATED TEXT PRODUCTS WILL BE ISSUED SHORTLY.
COCKRELL
PREV DISCUSSION... /ISSUED 700 PM CDT SUN MAY 26 2013/
UPDATE...
HAVE UPDATED GRAPHICAL FORECASTS...CALLING FOR SCATTERED TO ISOLATED
SHOWERS AND THUNDERSTORMS ACROSS SOUTHEAST TEXAS PANHANDLE THROUGH
THE EVENING. EXPECT CONVECTION TO BE MAINLY CONTAINED SOUTHEAST
TEXAS PANHANDLE...WHERE NEWLY DEVELOPED CELLS WILL BE
PROPAGATING...DUE TO SUPPORT OF WEAK SHORTWAVE TROF. UPDATED TEXT
PRODUCTS WILL BE ISSUED SHORTLY.
COCKRELL
PREV DISCUSSION... /ISSUED 626 PM CDT SUN MAY 26 2013/
AVIATION...
00Z TAF CYCLE
A DRYLINE JUST EAST OF THE GUYMON AND AMARILLO TAF SITES ALONG WITH
AN UPPER TROUGH MOVING ACROSS THE PANHANDLES EARLY TONIGHT WILL
PRODUCE ISOLATED TO SCATTERED CONVECTION. THIS CONVECTION IS EXPECTED
TO REMAIN EAST OF THE THREE TAF SITES. VFR CONDITIONS ALONG WITH
SOUTHWESTERLY WINDS 15 TO 25 KNOTS WITH HIGHER GUSTS AFTER 15Z
MONDAY...AND 10 TO 20 KNOTS BEFORE 15Z MONDAY WILL PREVAIL.
SCHNEIDER
PREV DISCUSSION... /ISSUED 405 PM CDT SUN MAY 26 2013/
DISCUSSION...
THERE REMAINS A LARGE AMOUNT OF POTENTIAL FOR WEATHER ACROSS THE
PANHANDLES FOR THE NEXT SEVERAL DAYS BUT THE QUESTION WILL BE CAN WE
TURN THAT POTENTIAL INTO REALITY.
ACROSS THE NORTHWEST TEXAS AND WESTERN OKLAHOMA PANHANDLE REMAIN A
PRIME AREA FOR CRITICAL FIRE WEATHER CONDITIONS TO DEVELOP THIS
AFTERNOON AS THE DRYLINE SNEAKS INTO THE PANHANDLES. AS A RESULT
WILL LEAVE THE RED FLAG IN PLACE AND UNMODIFIED. FOR THE EASTERN
PANHANDLES THERE REMAINS A STRONG TO SEVERE STORM POTENTIAL THIS
AFTERNOON INTO THE OVERNIGHT HOURS. TTU WRF AND RUC HRRR SOLUTIONS
SHOW ISOLATED CONVECTION INITIATING ALONG AND EAST OF A VEGA TO
GUYMON LINE. RUC BUFR SOUNDINGS SHOW A WEAK CAP INHIBITING
INITIATION OF THESE STORMS UNTIL 6-7PM THIS EVENING. SHOULD THESE
STORMS FORM THEY WOULD BE ABLE TO TAP INTO ELEVATED INSTABILITY IN
THE RANGE OF 1000-1500 J/KG. DEEP LAYER SHEAR IN THE AREA OF LIKELY
INITIATION IS 25 TO 35 KT WITH A SLIGHT VEERING PATTERN. GIVEN
THE DEEP DRY LAYER BENEATH THE EXPECTED STORM BASES DAMAGING WINDS
OF 65 TO 70 MPH WOULD BE THE PRIMARY HAZARD BUT A HAIL THREAT CAN
NOT BE RULED OUT. ALL OF THIS IS ASSUMING THE WEAK CAP CAN BE
OVERCOME TO ALLOW STORMS TO DEVELOP. ANY STORMS THAT MAY DEVELOP
SHOULD DIMINISH BY 2 AM MONDAY MORNING.
DURING THE DAY MONDAY...THE DRYLINE WILL RACE ACROSS THE PANHANDLES
AND INTO WESTERN OKLAHOMA. THIS WILL PLACE THE VAST MAJORITY OF THE
PANHANDLES UNDER EXTREMELY DRY CONDITIONS WHICH COULD LEAD TO THE
RAPID SPREAD OF FIRE. WITH THAT BEING SAID RECENT RAINS PLUS ANY
ADDITIONAL RAIN WE GET TONIGHT WILL HELP TO MITIGATE SOME OF THIS
POTENTIAL. HAVE DECIDED TO NOT CARRY HEADLINES FOR MONDAY DUE TO THE
UNCERTAINTY OF PRECIP AMOUNTS AND COVERAGE FROM ANY STORMS
TONIGHT...BUT IF NO PRECIPITATION OCCURS A RED FLAG WARNING MAY BE
NEEDED FOR THE SIZABLE CHUNK OF THE AREA.
MODELS HAVE COME INTO A DECENT AGREEMENT FOR THE MID WEEK SYSTEM
WITH THE ECMWF LAGGING BEHIND THE OTHER MODELS SLIGHTLY. ALSO OF
NOTE HAS BEEN A SLIGHT INCREASE IN SPEED OF THE SYSTEM PLACING
BETTER PRECIP CHANCES ON TUESDAY AND CAUSING PRECIP CHANCES TO OCCUR
EARLIER IN THE DAY ON WEDNESDAY.
TUESDAY WILL BE A MIX OF FIRE WEATHER CONCERNS ACROSS THE WEST AND
ISOLATED SEVERE WEATHER CONCERNS ACROSS THE SOUTHEAST. THE POSITION
OF THE DRYLINE WILL BE THE MAJOR DETERMINING FACTOR AS TO WHO GETS
WHAT. FOR NOW HAVE GONE WITH A SPLIT OF THE GFS AND NAM ON DRYLINE
PLACEMENT WHICH ENDS UP BEING ROUGHLY ALONG A GUYMON TO CLAUDE LINE.
LOCATIONS WEST OF THIS LINE WILL HAVE A BETTER CHANCE FOR SEEING
ELEVATED TO NEAR CRITICAL FIRE WEATHER CONDITIONS...AND LOCATION
EAST OF THIS LINE WILL HAVE THE BETTER CHANCE OF SEEING
PRECIPITATION. LOOKING AT THE SYNOPTIC SCALE...A SHORTWAVE IS PROGGED TO
ROTATE AROUND THE BASE OF THE MAIN UPPER LEVEL TROUGH. THIS SYNOPTIC
LIFT COUPLED WITH CONVERGENCE ALONG THE DRYLINE COULD BE ENOUGH TO
INITIATE STORMS DURING THE AFTERNOON HOURS OF TUESDAY. DEEP LAYER
SHEAR FOR THIS TIME RANGES FROM 20 TO 35 KT AND INSTABILITY VALUES
RANGE FROM 1500 TO 2500 J/KG. STRONG TO SEVERE STORMS CAN NOT BE
RULED OUT AT THIS TIME WITH LARGE HAIL AND DAMAGING WINDS BEING THE
PRIMARY THREATS.
WEDNESDAY THE MAIN UPPER LEVEL TROUGH LOOKS TO TAKE A NEUTRAL TO
SLIGHTLY NEGATIVE TILT AS IT APPROACHES THE PANHANDLES. INSTABILITY
VALUES LOOK TO HAVE LOWERED SLIGHT WHICH COULD ALSO MEAN THAT THE
SEVERE THREAT MAY ALSO HAVE DIMINISHED SLIGHTLY. WITH THAT BEING
SAID CAPE VALUES OF 1000 TO 2000 J/KG AND DEEP LAYER SHEAR OF 35 TO
45 KT WILL KEEP AT LEAST THE CHANCE FOR STRONG STORMS AND A POSSIBLE
ISOLATED SEVERE STORM POSSIBLE. LARGE HAIL AND DAMAGING WINDS WILL
BE THE PRIMARY HAZARD.
THURSDAY THE UPPER FLOW BECOMES MORE ZONAL TO KEEP THAT AREA DRY AND
A WEAK COLD FRONT WILL DROP INTO THE PANHANDLES FRIDAY. CONDITIONS
LOOK TO REMAIN DRY GOING INTO THE WEEKEND.
FIRE WEATHER...
CRITICAL FIRE WEATHER CONDITIONS ARE STILL EXPECTED TO DEVELOP
ACROSS THE NORTHWESTERN TEXAS PANHANDLE AND WESTERN OKLAHOMA
PANHANDLE THIS AFTERNOON. OVERNIGHT THE DRYLINE WILL RETREAT AND
ALLOW RELATIVE HUMIDITIES TO RECOVER. HOWEVER...THE NORTHWESTERN
TEXAS AND WESTERN OKLAHOMA PANHANDLE MAY ONLY RECOVER SLIGHTLY WITH
MAXIMUM RELATIVE HUMIDITIES OF 30 TO 40 PERCENT.
ELEVATED TO NEAR CRITICAL FIRE WEATHER CONDITIONS WILL BE LIKELY ON
MONDAY FOR MUCH OF THE PANHANDLES AS RELATIVE HUMIDITIES DROP INTO
THE TEENS AND SINGLE DIGITS WITH SOUTHWEST 20 FOOT WINDS OF 20 TO 25
MPH WITH HIGHER GUSTS. THE RECENT RAINFALL ACROSS THE SOUTHERN TEXAS
PANHANDLE AND ANY ADDITIONAL RAINFALL TONIGHT WILL PROVIDE SOME
LIMITATIONS ON FIRE POTENTIAL...TO GO ALONG WITH LOW FUEL LOADING
DUE TO THE ONGOING DROUGHT. FOR NOW WILL KEEP HEADLINES SILENT FOR
THIS TIME PERIOD.
ELEVATED TO NEAR CRITICAL FIRE WEATHER CONDITIONS MAY DEVELOP ACROSS
THE WESTERN PANHANDLES TUESDAY AFTERNOON AS RELATIVE HUMIDITIES DROP
INTO THE SINGLE DIGITS ONCE AGAIN BEHIND THE DRYLINE AND 20 FOOT
SOUTHERLY WINDS OF 15 TO 25 MPH WINDS. HOWEVER PRECIP CHANCES WILL
BEGIN TO ENTER THE PANHANDLES DURING THE LATE AFTERNOON AND EVENING
HOURS WHICH COULD BRING AN EARLY END TO FIRE WEATHER CONDITIONS.
FIRE WEATHER CONDITIONS FROM WEDNESDAY THROUGH THE REST OF THE WORK
WEEK WILL BE HIGHLY DEPENDENT ON PRECIPITATION EXPECTED TUESDAY AND
WEDNESDAY. SHOULD THE WESTERN PANHANDLES GET LITTLE TO NO
PRECIPITATION TUESDAY AND WEDNESDAY...THEN ELEVATED TO NEAR CRITICAL
FIRE WEATHER CONDITIONS COULD BE POSSIBLE TUESDAY AFTERNOON...AND
ELEVATED FIRE WEATHER CONDITIONS THURSDAY AND FRIDAY.
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
11/03
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
935 PM CDT TUE MAY 28 2013
.UPDATE...
ISSUED AT 935 PM CDT TUE MAY 28 2013
CONVECTION AS ANTICIPATED INITIATED AND PERSISTS FROM KANSAS INTO
NORTHERN MISSOURI...SOUTHERN IOWA AND NORTHERN ILLINOIS. THIS
CONVECTION FORMED ON OR JUST TO THE NORTH OF A SURFACE WARM
FRONTAL BOUNDARY...WHICH HAS BEEN SLOWLY SHIFTING BACK SOUTH DUE
TO CONVECTIVE OUTFLOWS. 850MB RADAR AND VWP DATA SHOWED SOUTHWEST
35-45 KT WINDS FROM EASTERN KANSAS INTO SOUTHERN WISCONSIN...
PUMPING GULF OF MEXICO MOISTURE INTO THIS CONVECTION. THE FORECAST
AREA LIES ON THE SUBSIDENT SIDE OF THE CONVECTION...AS WELL AS IN
RIDGING BUILDING IN BEHIND A SHORTWAVE IN NORTHERN WISCONSIN. AS A
RESULT...DRY CONDITIONS ARE OCCURRING OVER THE FORECAST AREA.
NUMEROUS HRRR RUNS...INCLUDING THE LATEST AVAILABLE 29.00Z
HRRR...CONTINUE TO DEPICT A DRY FORECAST FOR THE AREA THROUGH 12Z
AND EVEN BEYOND. THE 28.00Z NSSL WRF-ARW ALSO DEPICTS A DRY
FORECAST...WITH BOTH MODELS SUGGESTING ALL CONVECTION STAYS HUNG
UP ACROSS SOUTHERN IOWA OR POINTS SOUTH. THIS MAKES SENSE GIVEN
THE DRIFT SOUTH OF THE WARM FRONT FROM OUTFLOWS...THOUGH THE DRIFT
SOUTH MAY BEGIN TO STOP SOON WITH UPPER RIDGING BUILDING ACROSS
THE CENTRAL AND SOUTHERN PLAINS. ADDITIONALLY...UPPER RIDGING
BUILDING IN BEHIND THE SHORTWAVE HEADING INTO NORTHERN WISCONSIN
SHOULD PROVIDE ADDED SUBSIDENCE. THUS...WENT WITH A DRY FORECAST
THROUGH 12Z.
WILL DEFINITELY HAVE TO WATCH THE FOG SITUATION OVERNIGHT.
TEMP/DEWPOINT SPREADS ARE ALREADY FAIRLY LOW...ESPECIALLY NORTH
OF I-90. SO FAR VISIBILITIES ARE BEHAVING...STAYING AT 4-5 MILES
OR HIGHER. COMBINATION OF BLOWOFF FROM CONVECTION TO THE SOUTH AND
LOW CLOUDS SHOULD PRECLUDE GOOD RADIATIONAL COOLING TO FORM FOG.
THUS...TO GET DENSE FOG...WE WILL NEED CEILINGS TO LOWER.
CONFIDENCE IS TOO LOW TO PUT OUT A DENSE FOG ADVISORY NOW...BUT
CANNOT RULE OUT ONE NEEDED LATER.
&&
.SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT)
ISSUED AT 325 PM CDT TUE MAY 28 2013
MAIN FORECAST CONCERNS THIS PERIOD...SHRA/TSRA CHANCES THRU THE
PERIOD...RAIN AMOUNTS/SEVERE THREAT WED AFTERNOON/EVENING.
18Z DATA ANALYSIS HAD A WARM/STATIONARY FRONT NEAR THE WI/IL
BORDER...SOUTHWEST TO A LOW OVER NORTHEAST NM. WV IMAGERY AND EVEN
IR/VIS IMAGERY DEPICTED A RATHER VIGOROUS MID LEVEL SHORTWAVE MOVING
EAST ACROSS SOUTHWEST MN. NORTH OF THE FRONT AND AHEAD OF THE
SHORTWAVE...LOW CLOUDS...PATCHY BR/-DZ PERSISTED ACROSS MUCH OF
MN/WI. ACROSS MUCH OF IA...IN THE WAKE OF A SHORTWAVE THAT PASSED
EARLY THIS MORNING...CLOUDS WERE A LITTLE THINNER WITH SOME
SUNSHINE IN THE SUBSIDENCE BEHIND THAT SHORTWAVE. ACROSS MUCH OF
MN/WI WHERE THE LOW CLOUDS/LACK OF SUNSHINE PERSISTED...MID-DAY
TEMPS REMAINED COOL...IN THE 50S TO LOW 60S.
SOME MINOR DIFFERENCES NOTED WITH 28.12Z MODEL INITIALIZATIONS...
BUT THE BIG PICTURE OF THE SOLUTIONS REMAINS QUITE SIMILAR THRU WED
NIGHT AND INTO FRIDAY. THERE WILL BE PERIODS/BREAKS FROM THE RAIN BUT
BETWEEN TONIGHT AND FRI ANOTHER COUPLE ROUNDS OF HEAVIER/MORE
WIDESPREAD RAIN LOOK TO SPREAD ACROSS THE AREA. DPROG/DT OF 500MB
HGTS AT 28.12Z SHOWED THE MODEL RUNS OF 26.12Z AND 27.12Z VERIFIED
QUITE WELL ACROSS NOAM/EASTERN PAC WHILE TRENDING TOWARD A TIGHTER...
COMMON CONSENSUS. SOLUTIONS CONTINUE TO CONVERGE TOWARD A TIGHTER...
COMMON CONSENSUS TONIGHT/WED AS HGTS RISE OVER THE REGION AND STRONG
TROUGHING DIGS THRU THE ROCKIES. IMPROVING CONSENSUS WED NIGHT AS
THE STRONG TROUGHING MOVES INTO THE CENTRAL CONUS. CHECK OF OBS
VS. MODEL DATA AT 18Z SHOWED THEM TO BE REASONABLE WITH THE CENTRAL
CONUS MASS FIELDS...THOUGH NAM/GEM WERE A BIT HIGH WITH SFC DEW
POINTS OVER MUCH OF IL. A BLEND OF THE MODELS LOOKED BEST WITH THE
12-18Z PRECIP OVER THE UPPER MIDWEST. NO CLEAR MODEL FAVORITE AND
PREFERRED A MODEL/ENSEMBLE CONSENSUS. SHORT-TERM FCST CONFIDENCE ON
THE GOOD SIDE THIS CYCLE.
FOR THE SHORT TERM...SOUTHWEST MN SHORTWAVE WILL PASS THIS EVENING...
TAKING SOME OF THE DEEPER MOISTURE/FORCING/LIFT WITH IT. LITTLE IN TH
WAY OF FORCING/LIFT SEEN FOR SHRA/TSRA CHANCES AFTER ABOUT 03Z. SOME
WEAK LOWER LEVEL WARM ADVECTION CONTINUES BUT MOST OF THIS LOOKS TO
GO INTO WARMING/RISING MID LEVEL HGTS BEHIND THE SHORTWAVE. LEFT SOME
SMALL -SHRA/ISOLATED TSRA CHANCES IN THE FCST GRIDS TONIGHT...MAINLY
ACROSS THE SOUTHEAST HALF OF THE FCST AREA WHERE SOME 500-1000 J/KG
MU CAPE LOOKS TO REMAIN THRU THE NIGHT...AND BLENDS WELL WITH
NEIGHBORING GRIDS. VIS IMAGERY SHOWS THERE SHOULD BE SOME DECREASE OF
CLOUDS IN THE WAKE OF THE SHORTWAVE FOR LATER THIS EVENING/OVERNIGHT.
WITH THE VERY MOIST BOUNDARY LAYER AND LIGHT WINDS...AREAS/PATCHY
FOG SHOULD FORM...ESPECIALLY WHERE CLOUDS/LIGHT PRECIP HELD TEMPS
DOWN TODAY.
THE FRONTAL BOUNDARY GETS A PUSH NORTHWARD ON WED AS THE ROCKIES
TROUGHING MOVES INTO THE PLAINS AND DEEPER/STRONGER SOUTHERLY FLOW
DEVELOPS OVER THE MID/UPPER MS VALLEY. PW VALUES IN THE AIRMASS
BEING PUSHED INTO/OVER THE WARM FRONT IN THE 1.5 TO 1.75 INCH RANGE
ON NOSE OF 35-50KT 850MB JET/MOISTURE TRANSPORT/THETA-E CONVERGENCE.
1K-2K J/KG MU CAPE INDICATED AS WELL IN THIS AIRMASS. RAISED SHRA/
TSRA CHANCES FOR WED INTO THE 70-80 PERCENT RANGE AS THE WARM FRONT
LIFTS NORTH INTO THE AREA. INCREASING WIND FLOW SHOULD KEEP ANY TSRA
PROGRESSIVE ON WED. WITH A BREAK TONIGHT AND PLENTY OF MODEL DETAIL
DIFFERENCES WITH PRECIP AMOUNTS WED...HELD OFF ON RE-ISSUING A FLASH
FLOOD WATCH ON WED FOR NOW. AREA LOOKS TO GET ANOTHER BREAK FROM THE
MORE WIDESPREAD SHRA/TSRA WED NIGHT WITH THE WARM FRONT LIFTING
NORTH OF THE AREA AND THE PLAINS LOW COLD FRONT AND NEXT ROUND OF
STRONGER/LARGER SCALE FORCING REMAINING WELL WEST OF THE AREA.
ONE OF THE BIGGER CONCERNS IS HIGHS ON WED. MUCH OF THE GUIDANCE IS
STILL PUSHING WED HIGHS INTO THE UPPER 70S/LOW 80S. WITH SHRA/TSRA
LIKELY TO DELAY THE WARM FRONT LIFTING THRU THE AREA...PLUS PLENTY
OF CLOUDS AND THE SHRA/TSRA...LOWERED HIGHS FOR WED MOSTLY INTO THE
MID 70S...AND EVEN THIS MAY STILL BE 5-10F TOO WARM. HIGHS WED WILL
IMPACT HOW MUCH CAPE DEVELOPS OVER THE AREA AND ANY SEVERE STORM
THREAT. PROXIMITY OF THE WARM FRONT AND ENHANCED LOW LEVEL HELICITY
MAY ALLOW SEVERE STORMS TO DEVELOP...IF THEY CAN GET ROOTED IN THE
BOUNDARY LAYER. SEE SWODY2 FOR MORE DETAILS OF THE WED SEVERE THREAT.
FOR NOW WED HIGHS IN THE MID 70S BLEND WELL WITH NEIGHBORING GRIDS.
USED A BLEND OF GUIDANCE LOWS FOR TONIGHT/WED NIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 325 PM CDT TUE MAY 28 2013
FORECAST CONCERNS THU INTO FRI ARE SHRA/TSRA CHANCES AND POTENTIAL
FOR HEAVY RAINS/SEVERE STORMS AS THE COLD FRONT MOVES THRU THE AREA.
MODELS STAY IN REASONABLE AGREEMENT THU/FRI AS THE PLAINS TROUGH
LIFTS NORTH THU..THEN DEVELOPS A 500MB LOW OVER THE DAKOTAS BY FRI.
RATHER ENERGETIC SYSTEM DEVELOPS A STRONG SFC LOW OVER THE DAKOTAS
BY MID-DAY THU. SFC SYSTEM OCCLUDES AND PUSHES THE COLD FRONT TOWARD
THE AREA THU THEN INTO THE AREA THU NIGHT. THIS INTO THE AIRMASS WITH
1K-2K J/KG MU CAPE AND 1.5 TO 1.75 INCH PW VALUES...ALONG WITH
STRENGTHENING WIND FIELDS. SWODY3 QUITE REASONABLE AT THIS TIME.
POTENTIAL REMAINS FOR REPEAT STRONGER...HEAVY RAIN PRODUCING TSRA
THU/THU EVENING AND APPEARS ANOTHER FLASH FLOOD WATCH WILL BE NEEDED
FOR THIS TIME PERIOD. WILL CONTINUE ESFARX ADDRESSING THIS POTENTIAL
FOR NOW AND GIVE CREWS TONIGHT/WED A COUPLE MORE MODEL RUNS TO
DETAIL WHERE ANY FLASH FLOOD WATCH MAY BE NEEDED. RAISED SHRA/TSRA
CHANCES FOR THU/THU EVENING INTO THE 70-80 PERCENT RANGE FOR MUCH OF
THE AREA. WITH THE MID LEVEL TROUGH AXIS REMAINING WEST OF THE AREA
AND WHAT LOOKS TO BE A SECOND SFC COLD FRONT/TROUGH TO PUSH TOWARD
THE AREA...CONTINUED SHRA/TSRA CHANCES FRI/FRI NIGHT LOOK GOOD. GIVEN
SOME TIMING DIFFERENCES...USED THE MODEL/ENSEMBLE CONSENSUS GUIDANCE
FOR HIGHS/LOWS THU THRU FRI NIGHT.
MEDIUM RANGE MODEL RUNS OF 28.00Z AND 28.12Z IN REASONABLY GOOD
AGREEMENT WITH EACH OTHER AND OFFER AN IMPROVING CONSENSUS OVER
THEIR PREVIOUS RUNS FOR SAT THRU MON. THIS AS THE MID TROUGH
SWINGS ACROSS THE UPPER MIDWEST SAT/SAT NIGHT AND SHORTWAVE
RIDGING BUILDS IN BY LATER SUN AND FOR MON. LESSER CONSISTENCY BY
TUE...BUT A SIGNAL FOR ANOTHER STRONGER SHORTWAVE TROUGH TO BE
MOVING THRU THE NORTHERN ROCKIES... PUSHING THE SHORTWAVE RIDGE
AXIS INTO THE EASTERN GREAT LAKES. FCST CONFIDENCE AVERAGE TO GOOD
SAT-MON THEN AVERAGE BY TUE.
WITH THE MID LEVEL TROUGH AXIS STILL WEST OF THE AREA SAT...COOL/
COOLING 850- 500MB TEMPS/STEEPER MID LEVEL LAPSE RATES AND PW
VALUES REMAINING AROUND AN INCH...SHRA/TSRA CHANCES LOOKING TO
LINGER ON SAT. TROUGH AXIS PASSES LATE SAT NIGHT/EARLY SUN FOR
WHAT LOOKS TO BE A MUCH NEEDED DRIER PERIOD SUN AND ESPECIALLY MON
AS CAN HIGH PRESSURE AND THE SHORTWAVE RIDGING ALOFT BUILD EAST
INTO THE WESTERN GREAT LAKES.
NEXT TROUGH CROSSING THE ROCKIES MON NIGHT/TUE DEVELOPS LOW
PRESSURE IN THE CENTRAL/NORTHERN PLAINS...WITH INCREASING SOUTH/
SOUTHWEST FLOW...PW VALUES AND MOISTURE TRANSPORT/THETA-E CONVERGENCE
INTO THE UPPER MIDWEST ON TUE. SHRA/TSRA CHANCES LOOKING TO ALREADY
RETURN ON TUE. MODEL/ENSEMBLE CONSENSUS FOR HIGHS/LOWS SAT-TUE
APPEAR WELL TRENDED WITH TEMPS REMAINING BELOW TO NEAR NORMAL.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 639 PM CDT TUE MAY 28 2013
LATEST SURFACE ANALYSIS PUTS THE WARM FRONT FROM CENTRAL IOWA TO
NEAR KMSN WITH CALM OR VARIABLE WINDS NORTH OF THE BOUNDARY. CLOUD
DECK HAS BEEN SCATTERING OUT SOME IN THE WAKE OF AN UPPER LEVEL
DISTURBANCE MOVING THROUGH...WHICH COMPLICATES THE EVENING AND
OVERNIGHT FORECAST SOME. SETUP IS FAVORABLE FOR DENSE FOG AT BOTH
KRST/KLSE WITH RECENT RAINS...DAYTIME CLOUD COVER...AND
LIGHT/VARIABLE WINDS. HOWEVER...THERE REMAINS SOME UNCERTAINTY IN
HOW CIRRUS CLOUDS ASSOCIATED WITH CONVECTION IN SOUTHERN IOWA
STREAMING NORTH...AND SOME DRYING IN THE WAKE OF SHORTWAVE...WILL
INFLUENCE FOG POTENTIAL. MODEL GUIDANCE PROBABILITIES AND OVERALL
FORECAST CONFIDENCE IS STILL HIGH FOR BOTH VISIBILITIES AND
CEILINGS DROPPING TO IFR/LIFR LATE TONIGHT. AS WARM FRONT LIFTS
THROUGH THE REGION WEDNESDAY MORNING...SCATTERED SHOWERS AND
IMPROVING CEILINGS ARE EXPECTED. BY AFTERNOON THROUGH THE
REMAINDER OF THE PERIOD...SCATTERED THUNDERSTORMS ARE LIKELY BUT
CONFIDENCE IS LOWER IN WHERE AND WHEN THESE STORMS WILL TRACK
ACROSS THE REGION.
&&
.HYDROLOGY...TONIGHT THROUGH FRIDAY
ISSUED AT 325 PM CDT TUE MAY 28 2013
A COUPLE ROUNDS OF MORE WIDESPREAD SHRA/TSRA ARE EXPECTED FROM
WEDNESDAY THROUGH FRIDAY AND A FLASH FLOOD WATCH WILL LIKELY BE
NEEDED DURING SOME PORTION OF THIS TIME-FRAME. THE FIRST ROUND COMES
WED AS A WARM FRONT LIFTS INTO/ACROSS THE AREA...WITH WHAT LOOKS TO
BE MORE PROGRESSIVE SHRA/TSRA AND MOST RAIN AMOUNTS IN THE 0.25 TO
0.5 INCH RANGE. THE SECOND MORE WIDESPREAD ROUND OF SHRA/TSRA MOVES
ACROSS THE AREA THU/THU EVENING...AHEAD OF A COLD FRONT. THERE IS
MORE POTENTIAL FOR REPEAT...HEAVY RAIN PRODUCING TSRA THU/THU
EVENING GIVEN THE WIND FIELDS AND SLOWER MOVING FRONT. RAIN AMOUNTS
OF 1 TO 2 INCHES...WITH LOCALLY HEAVIER AMOUNTS...ARE QUITE POSSIBLE
THU/THU NIGHT. A FLASH FLOOD WATCH WILL MORE LIKELY BE NEEDED FOR
PORTIONS OF THE AREA WITH THIS ROUND OF SHRA/TSRA. LARGER RIVERS WILL
ALSO SEE CONTINUED RISES AND POSSIBLE FLOODING THIS WEEK WITH THE
PROLONGED PERIOD OF COOL/WET WEATHER. CONTINUE TO MONITOR RIVER
FORECASTS AND STATEMENTS CLOSELY THIS WEEK.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...AJ
SHORT TERM...RRS
LONG TERM....RRS
AVIATION...ZT
HYDROLOGY....RRS
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
837 PM CDT TUE MAY 28 2013
.UPDATE...
THE BULK OF THE HEAVY WEATHER HAS STAYED SOUTH OF WISCONSIN THIS
EVENING. HOWEVER...THERE HAS BEEN RECENT DEVELOPMENT ALONG THE
VERY WEAKLY DEFINED SURFACE BOUNDARY RUNNING FROM ABOUT
MILWAUKEE...SOUTHWEST TO JANESVILLE. OR...THESE STORMS ARE LINING
UP ALONG SOME GRAVITY WAVE KICKED FROM THE STORMS TO THE SOUTH. EITHER
WAY...WE HAVE PLENTY OF INGREDIENTS IN PLACE FOR THESE STORMS TO
INTENSIFY FURTHER. THEY HAVE A LONG WAY TO GO TO GET SEVERE...BUT
THEY COULD KICK OUT SOME HAIL AND GUSTY WINDS BEFORE MOVING OUT BY
MIDNIGHT. ALSO...HEAVY RAIN IS A GIVEN WITH THE VERY HIGH
PRECIPITABLE WATER VALUES STILL IN PLACE. THE HRRR THEN HAS US
HIGH AND DRY THROUGH THE REST OF THE NIGHT WITH THE NEXT ROUND OF
STORMS WAITING UNTIL WE HEAT UP TOMORROW.
&&
.AVIATION/06Z TAFS/...
CONFIDENCE IS PRETTY LOW ON TRENDS FOR TONIGHT. MOST GUIDANCE
SUPPORTS CONDITIONS DROPPING TO IFR/LOW IFR LEVELS AFTER MIDNIGHT
AS THE WINDS BECOME LIGHT AND VARIABLE. HOWEVER...SUBSIDENCE
AROUND THE CURRENT STORMS HAS BROUGHT WHAT SHOULD BE TEMPORARY
IMPROVEMENT. HIGH DEWPOINTS ARE IN PLACE AND THIS SHOULD ALLOW THE
COLD LAKE MICHIGAN AIR TO COMBINE AND RESULT IN SOME DENSE FOG AT
KMKE AT TIMES. NOT CONFIDENT ENOUGH TO PUT IT IN THE TAF AT THIS
TIME...BUT IT IS A CONCERN. THE FRONTAL BOUNDARY IS RIGHT OVER OR
MAY SAG SOUTH OF KMSN...SO LOW CLOUDS AND FOG SHOULD FILL BACK IN
THERE. THE FRONT WILL SHIFT NORTH TOMORROW WITH VFR CONDITIONS
RETURNING BY MID TO LATE MORNING ON WEDNESDAY FOR ALL TAF SITES.
&&
.PREV DISCUSSION... /ISSUED 335 PM CDT TUE MAY 28 2013/
VERY SHORT TERM...TONIGHT AND WEDNESDAY.
SHORT TERM FORECAST CHALLENGE WILL BE THE POSSIBILITY FOR DENSE FOG
OVERNIGHT. WITH LIGHT EASTERLY FLOW AT THE SURFACE ON THE NORTH SIDE
OF THE WARM FRONT...AREAS OF FOG ARE EXPECTED AND COULD BECOME
DENSE. BEST CHANCE FOR DENSE FOG WOULD BE THE NORTH HALF OF THE MKX
FORECAST AREA...NORTH OF MILWAUKEE AND MADISON.
THE SURFACE WARM FRONT CREPT INTO SOUTHERN WISCONSIN TODAY AND
ALREADY REACHED MADISON AND MILWAUKEE EARLY THIS AFTERNOON.
DEWPOINTS ARE RISING INTO THE MID 60S WILL HOLD TEMPS UP THROUGH THE
NIGHT. LIGHT SHOWERS AND DRIZZLE ASSOCIATED WITH THE WARM FRONT AND
SURFACE THETA-E ADVECTION WILL PERSIST THROUGH THE EVENING. SURFACE
BASED AND MIXED LAYER CAPE IS ON THE RISE...UP TO AROUND 1500 J/KG
WITH MINIMAL CIN IN FAR SOUTHERN WI. LOW LEVEL LAPSE RATES ARE
FAIRLY WEAK. THUS...ONLY ISOLATED THUNDER EXPECTED WITH THESE
SHOWERS.
MEANWHILE...A SHORTWAVE MOVING INTO WEST CENTRAL WI IS PRODUCING AN
AREA OF SHOWERS. THESE ARE IN THE STABLE AIR AHEAD OF THE SURFACE
WARM FRONT. THESE WILL LIKELY STAY NORTHWEST OF THE MKX FORECAST
AREA THIS EVENING.
CONVECTION HAS BEGUN OVER SOUTH CENTRAL IOWA THIS AFTERNOON AND ALL
MODELS KEEP THE STRONGER STORMS CONFINED TO NORTHERN IL AND
SOUTHWARD. THERE COULD BE SHOWERS AND ISOLATED STORMS ON THE
NORTHERN SIDE OF ANY ORGANIZED CONVECTION THAT COULD CLIP SOUTHERN
WI LATE TONIGHT INTO WEDNESDAY MORNING. THESE WOULD BE ELEVATED OVER
SOUTHERN WI AND NOT EXPECTING A RISK FOR SEVERE WITH THEM HERE.
THERE WILL BE SOME TIME FOR THE ATMOSPHERE TO RECOVER ENOUGH TO
SUPPORT SURFACE-BASED CONVECTION WEDNESDAY AFTERNOON WITH A STRONG
SHORTWAVE MOVING ACROSS MN AND CENTRAL WI. MKX AREA WILL BE ON THE
EASTERN FRINGE OF THIS DISTURBANCE AND THE LOW LEVEL JET WILL BE
POINTING TOWARD SOUTHERN MN DURING THIS TIME. SPC EXPANDED THE
SLIGHT RISK INTO WESTERN AND PORTIONS OF SOUTH CENTRAL WI FOR
WEDNESDAY. MIXED LAYER CAPE VALUES GET INTO THE 1000-1500 J/KG RANGE
WITH MODERATE BULK SHEAR TO SUPPORT MARGINALLY SEVERE HAIL AND HIGH
WIND GUSTS. WITH PRECIPITABLE WATER VALUES UP AROUND 1.4 IN...HEAVY
DOWNPOURS WILL BE LIKELY.
SHORT TERM...WEDNESDAY NIGHT THROUGH FRIDAY.
SHARPENING UPSTREAM TROUGH WILL RESULT IN INCREASING LOW LEVEL
SOUTHERLY WINDS AND MILD MORE HUMID CONDITIONS LINGERING FOR MUCH OF
THE PERIOD. LOW LEVEL JET REFOCUSES TO THE WEST WEDNESDAY NIGHT
ACROSS IA/MN AND THEN VEERS EAST INTO SOUTHERN WI ON THU AND
CONTINUES OVER THE AREA THU NIGHT. BEST CHANCE FOR WIDESPREAD
CONVECTION APPEARS TO BE THURSDAY NIGHT WHEN VIGOROUS MID-LEVEL
SHORT WAVE ROTATES AROUND NORTHERN PLAINS UPPER LOW AND AFFECTS
SOUTHERN WI. OCCLUDED FRONT WEAKENS OVER THE WESTERN GTLAKES BY
FRIDAY BUT LINGERING SOUTHWEST FLOW AND INSTABILITY WILL LIKELY
RESULT IN MORE CONVECTION AT TIMES THROUGH THE DAY.
LONG TERM...FRIDAY NIGHT THROUGH TUESDAY.
LINGERING UPPER LOW PRESSURE TROUGH OVER WESTERN GTLAKES WILL
CONTINUE TO CAUSE A CHANCE FOR SHOWERS AND THUNDERSTORMS EARLY IN
THE PERIOD AS MEDIUM RANGE GUIDANCE IN GOOD AGREEMENT ON TROUGH AXIS
REMAINING WEST OF AREA THROUGH SATURDAY NIGHT. SHORT WAVE TROUGH
PUSHING ACROSS THE PACIFIC NORTHWEST DURING THE WEEKEND WILL NUDGE
GTLAKES UPPER LOW EASTWARD LATE IN THE WEEKEND...ALLOWING DRY
WEATHER TO RETURN /ALBEIT BRIEFLY/FOR EARLY NEXT WEEK. SHORT WAVE
RIDGING RESULTING IN DRY WEATHER FOR MONDAY MOVES OFF TO THE EAST AS
PACIFIC SHORT WAVE RIDES RAPIDLY EAST-SOUTHEAST AND RETURNS A CHANCE
FOR CONVECTION TO THE AREA BY TUESDAY.
AVIATION /00Z TAFS/...THE WARM FRONT CREPT NORTHWARD QUICKER THAN
EXPECTED AND HAS ALREADY CLEARED KMSN AND KMKE...IDENTIFIED BY
SOUTHWEST WINDS AND SCOURING OF THE LIFR CIGS. THERE IS AN AREA OF
SHOWERS WITH ISOLATED THUNDER ACROSS FAR SOUTHERN WISCONSIN NOW THAT
WILL BRIEFLY IMPACT AT LEAST KMKE THROUGH THE NEXT HOUR. THE WARM
FRONT IS EXPECTED TO HANG UP NEAR SHEBOYGAN AND THE DELLS THROUGH
TONIGHT AND CONTINUE THE TREK NORTHWARD ON WEDNESDAY.
UNCERTAIN ABOUT CEILINGS TONIGHT SINCE THE WARM FRONT WILL BE VERY
CLOSE TO THE KMSN/KUES/KMKE TAF SITES. AREAS OF DENSE FOG AND LOW
CEILINGS WILL BE POSSIBLE MAINLY NORTH OF KMSN AND KMKE TONIGHT
ALONG AND NORTH OF THE WARM FRONT.
THE CHANCE FOR LIGHT RAIN SHOWERS/DRIZZLE WILL CONTINUE OVER ALL OF
SOUTHERN WI THROUGH TONIGHT. CHANCE FOR THUNDER ALONG AND SOUTH OF
THE WARM FRONT.
EXPECT IMPROVEMENT TO MVFR AND EVENTUALLY VFR AS REGION GETS INTO
WARM SECTOR AS WARM FRONT LIFTS INTO CENTRAL WISCONSIN. THIS MAY BE
DELAYED UNTIL EARLY WEDNESDAY MORNING.
MARINE...
MARINE DENSE FOG ADVISORY IN EFFECT AND EXTENDED THROUGH WEDNESDAY
MORNING FROM PORT WASHINGTON NORTH TO SHEBOYGAN IN THE VICINITY OF
THE SURFACE WARM FRONT. CANCELLED THE ADVISORY FOR ZONES SOUTH OF
PORT WASHINGTON...ALTHOUGH PATCHY FOG IS STILL POSSIBLE WITH THE
WARM MOIST AIR FLOWING OVER THE COOL WATER.
SOUTH WINDS WILL INCREASE THURSDAY...ALTHOUGH WINDS AND WAVES ARE
EXPECTED TO REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...DENSE FOG ADVISORY UNTIL 6 AM CDT WEDNESDAY FOR LMZ643.
&&
$$
UPDATE...DAVIS
TONIGHT/WEDNESDAY AND AVIATION/MARINE...MRC
WEDNESDAY NIGHT THROUGH TUESDAY...MBK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1123 PM CDT SUN MAY 26 2013
.UPDATE...
ISSUED AT 913 PM CDT SUN MAY 26 2013
CURRENTLY MONITORING SOME CONVECTION THAT HAS DEVELOPED ALONG THE
WESTERN MINNESOTA/IOWA BORDER ALONG THE NORTHEASTERN SIDE OF THE
850MB MOISTURE TRANSPORT. THE RAP HAS BEEN THE MOST CONSISTENT
THIS AFTERNOON/EVENING WITH SHOWING THIS MOISTURE TRANSPORT AND
0-3KM MUCAPE LIFTING NORTH-NORTHEAST OVERNIGHT WITH THIS
CONVECTION LIKELY REACHING NORTHEAST IOWA AND SOUTHEAST MINNESOTA
AFTER 6Z TONIGHT.
WITH SOIL CONDITIONS FAIRLY SATURATED ACROSS NORTHEAST IOWA AND
SOUTHEAST MINNESOTA DUE TO AN EXCESS OF 3 TO 6 INCHES OF RAINFALL
OVER THE PAST FEW WEEKS...AM INCREASINGLY CONCERNED FOR THE
POTENTIAL OF FLASH FLOODING ACROSS THIS REGION. THE MOST LIKELY
PERIOD FOR FLOODING IS EXPECTED TO COME ON MONDAY NIGHT AS A
STRONGER MID LEVEL SHORTWAVE TROUGH PROPAGATES NORTHEAST THROUGH
THE SOUTHWESTERLY FLOW ALOFT. WITH DEEP FORCING COMBINING WITH
HIGH PRECIPITABLE WATER VALUES APPROACHING 200 PERCENT OF NORM AND
INCREASING INSTABILITY...THE THREAT FOR FLASH FLOODING IS THE
HIGHEST MONDAY NIGHT INTO TUESDAY MORNING. BECAUSE OF THIS...HAVE
ISSUED A FLASH FLOOD WATCH FOR ALL OF NORTH CENTRAL AND NORTHEAST
IOWA. CONSIDERED A FLASH FLOOD WATCH FOR ALL OF SOUTHEASTERN
MINNESOTA...BUT WITH COLLABORATION FROM MPX HAVE DECIDED TO HOLD
OFF ON THAT AREA FOR NOW DUE TO CONFIDENCE IN HEAVY RAINFALL NOT
BEING AS HIGH THERE.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 310 PM CDT SUN MAY 26 2013
WARM FRONT THIS AFTERNOON IS SLOWLY MOVING NORTH ACROSS MISSOURI.
THE REMAINS OF THE CONVECTIVE COMPLEX FROM LAST NIGHT AND THIS
MORNING CONTINUES TO MOVE OFF TO THE EAST AND SHOULD NEARLY BE
OUT OF THE AREA BY 00Z. SECONDARY COMPLEX HAS DEVELOPED OVER
NORTHWEST IOWA AHEAD OF A SHORT WAVE TROUGH MOVING ACROSS SOUTH
DAKOTA. MESO MODELS ARE NOT HANDLING THIS FEATURE WELL AT ALL WITH
POSSIBLY THE EXCEPTION OF THE LOCAL ARXLAPS. THE 26.18Z RUN
CONTINUES TO MOVE THIS TO THE EAST/SOUTHEAST WITH ADDITIONAL
DEVELOPMENT FORMING SOUTH OF THE AREA ON A POSSIBLE BOUNDARY LEFT
BEHIND BY THIS MORNINGS COMPLEX. EITHER WAY...EXPECT MOST OF THE
ACTIVITY TO REMAIN SOUTH OF THE AREA EXCEPT FOR POSSIBLY SOME
SHOWERS COMING ACROSS THE SOUTHERN PARTS OF THE AREA THIS EVENING.
LOOKING TO THE OVERNIGHT HOURS...ANOTHER SHORT WAVE TROUGH IS
COMING ACROSS EASTERN WYOMING AND THE 26.12Z NAM AND GFS SHOW THE
MOISTURE TRANSPORT INCREASING AHEAD OF THIS WAVE WITH ANOTHER
COMPLEX OF STORMS EXPECTED TO DEVELOP OVER SOUTH DAKOTA. MODELS
THEN SHOW VARIED SOLUTIONS ON WHERE THIS COMPLEX GOES. THE NAM
BRINGS IT EAST ON THE NOSE OF THE MOISTURE TRANSPORT AND INTO THE
AREA AFTER MIDNIGHT. THE GFS AND 26.00Z ECMWF TAKE IT OFF TO THE
NORTHEAST IN THE SYNOPTIC FLOW WITH THE SHORT WAVE TROUGH. THE
26.12Z HI-RES ARW AND NMM BOTH START THE COMPLEX MOVING TO THE
EAST LIKE THE NAM BUT THEN RAPIDLY DIVE IT SOUTH TOWARD THE FRONT
AND BETTER CAPE AND NEVER GET IT HERE. GIVEN WHAT THE COMPLEXES
HAVE DONE THE PAST COUPLE OF NIGHTS WITH LITTLE OVERALL CHANGE IN
THE GENERAL PATTERN...PLAN TO SHOW THIS COMPLEX COMING INTO THE
AREA AFTER MIDNIGHT AND THEN MOVE EAST/SOUTHEAST ACROSS THE AREA
MONDAY.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 310 PM CDT SUN MAY 26 2013
STARTING TO BECOME CONCERNED THAT THE AREA COULD REALLY GET
PLASTERED WITH RAINFALL MONDAY NIGHT. THE UPPER LEVEL FLOW SHOULD
START TO BECOME A LITTLE MORE SOUTHWEST. THE NEXT SHORT WAVE
TROUGH WILL BE COMING OUT OF THE CENTRAL ROCKIES MONDAY AND MOVING
TOWARD THE AREA FOR MONDAY NIGHT. AS THIS WAVE COMES TOWARD THE
AREA...BOTH THE NAM AND GFS REALLY CRANK UP THE MOISTURE TRANSPORT
AS THE WARM FRONT STARTS TO APPROACH THE FROM THE SOUTH. THE NOSE
OF THE MOISTURE TRANSPORT IS EXPECTED TO BECOME FOCUSED ON THE
FORECAST AREA. THE ISENTROPIC UP GLIDE ON THE 300K SURFACE BECOMES
STRONG WITH THE NAM SHOWING VALUES OF 4 TO 6 UBAR/S. THE
COMBINATION OF THE FORCING FROM THE SHORT WAVE TROUGH...ISENTROPIC
UP GLIDE AND MOISTURE TRANSPORT SHOULD PRODUCE SHOWERS AND STORMS
FOR MUCH OF THE AREA WITH THE AXIS OF HEAVIEST RAIN ALONG THE I90
CORRIDOR. THE GFS FOCUSES ON THE SAME AREA BUT IS QUICKER WITH THE
DEVELOPMENT THAN THE NAM. HOWEVER...THE ECMWF KEEPS THE COMPLEX
MUCH CLOSER TO THE FRONT ACROSS THE IOWA/MISSOURI BORDER WITH
ANOTHER ONE TIED TO THE SHORT WAVE TROUGH GOING BY TO THE NORTH.
AT THIS TIME...PREFER THE SOLUTIONS OF THE NAM AND GFS BUT DID NOT
GO TO CATEGORICAL RAIN CHANCES AT THIS TIME TO HONOR THE ECMWF
SOLUTION. THAT COMPLEX IS THEN EXPECTED TO MOVE OUT TUESDAY BEFORE
THE POSSIBILITY OF ANOTHER ONE FOR TUESDAY NIGHT. BY THIS
TIME...CONFIDENCE ON WHERE THE FRONT WILL BE REALLY STARTS TO GO
DOWN BUT MOST MODELS EITHER HAVE IT OVER THE FORECAST AREA OR
EVEN TO THE NORTH AS THE FLOW BECOMES PROGRESSIVELY MORE
SOUTHWEST. BY THE MIDDLE OF THE WEEK...AN UPPER LEVEL LOW WILL BE
SLIDING TOWARD THE UPPER MIDWEST FROM THE PACIFIC NORTHWEST. THIS
IS EXPECTED TO KEEP THE SHORT WAVES ROTATING ACROSS THE REGION FOR
CONTINUED CHANCES OF SHOWERS AND THUNDERSTORMS. AT THIS TIME...IT
DOES NOT LOOK LIKE THERE WILL BE A BREAK IN THIS PATTERN UNTIL
NEXT WEEKEND AS THE LONG WAVE TROUGH AND UPPER LEVEL LOW FINALLY
START TO MOVE PAST THE REGION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1123 PM CDT SUN MAY 26 2013
A FAIRLY SHARP TRANSITION ZONE FROM VFR CONDITIONS TO IFR
CONDITIONS FROM THE MISSISSIPPI RIVER TO THE SOUTHWEST. EXPECT
THAT CEILINGS WILL GRADUALLY DROP THROUGH THE OVERNIGHT HOURS WITH
IFR MORE LIKELY TO OCCUR AT RST THAN LSE. THE CURRENT CONVECTION
ALONG THE IOWA/MINNESOTA BORDER IS EXPECTED TO STAY SOUTH OF THE
TAF SITES WITH THE BETTER CHANCES FOR RAIN AND/OR THUNDERSTORMS
COMING LATER ON MONDAY. OVERALL...CONFIDENCE IS NOT HIGH IN THE
EXACT TIMING OF WHEN THE ROUNDS OF PRECIPITATION WILL COME
THROUGH...BUT CONDITIONS SHOULD REMAIN MVFR TO IFR THROUGHOUT
REGARDLESS.
&&
.HYDROLOGY...
ISSUED AT 310 PM CDT SUN MAY 26 2013
WITH SEVERAL CONVECTIVE COMPLEXES EXPECTED TO IMPACT THE AREA OVER
THE NEXT FEW DAYS...THE CONCERN FOR FLOODING IS RISING. LAST NIGHTS
RAINS WERE GENERALLY AROUND A HALF INCH OR LESS AND EXPECTING
ABOUT THE SAME AMOUNTS AGAIN TONIGHT. THIS WILL FURTHER SATURATE
THE SOILS AND POSSIBLY SET THE STAGE FOR FLOODING MONDAY NIGHT AND
TUESDAY IF THAT COMPLEX DOES INDEED MOVE ACROSS THE AREA WITH
HEAVY RAIN. RAINFALL AMOUNTS THROUGH TUESDAY NIGHT COULD APPROACH
TWO INCHES WITH LOCALLY HIGHER AMOUNTS EXPECTED WITH
THUNDERSTORMS. SOILS AND RIVERS OVER SOUTHEAST MINNESOTA AND
NORTHEAST IOWA CAN NOT TAKE A LOT OF WATER BEFORE FLOODING WILL
START. WILL ISSUE AN ESF TO ADDRESS THESE CONCERNS. WILL LIKELY
NEED TO ISSUE A FLASH FLOOD WATCH WITH LATER FORECASTS IF IT
CONTINUES TO LOOK LIKE THE AREA WILL GET HIT MONDAY NIGHT AND
TUESDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...FLASH FLOOD WATCH THROUGH TUESDAY EVENING FOR IAZ008>011-018-019-
029-030.
&&
$$
UPDATE...HALBACH
SHORT TERM...04
LONG TERM...04
AVIATION...HALBACH
HYDROLOGY...04
AREA FORECAST DISCUSSION
NWS ALBANY NY
418 AM EDT WED MAY 29 2013
.SYNOPSIS...
SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A WARM FRONT
WILL MOVE THROUGH THE REGION THIS MORNING...ESPECIALLY FOR AREAS TO
THE NORTH OF INTERSTATE 90. AS AN UPPER LEVEL DISTURBANCE MOVES
CLOSE TO THE REGION...SOME STRONG THUNDERSTORMS ARE POSSIBLE THIS
AFTERNOON THROUGH THIS EVENING. MUCH WARMER TEMPERATURES AND MUGGY
CONDITIONS ARE EXPECTED FOR THE REMAINDER OF THE WEEK...WITH SOME
ADDITIONAL THUNDERSTORMS POSSIBLE OVER THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
...SEVERE THUNDERSTORMS POSSIBLE THIS AFTERNOON INTO THIS EVENING...
AS OF 418 AM EDT...A WARM FRONT WAS SITUATED JUST SOUTH OF THE
REGION ACROSS THE CENTRAL PA AND NJ. A BAND OF RAIN SHOWERS AND
ISOLD THUNDERSTORMS HAS MOVED ACROSS THE REGION...AND ADDITIONAL
SHOWERS AND EMBEDDED RUMBLES OF THUNDER ASSOCIATED WITH THE
BOUNDARY ITSELF WERE TO OUR WEST AND SOUTHWEST. DURING THE NEXT
SEVERAL HOURS...THESE SHOWERS AND EMBEDDED THUNDERSTORMS WILL MOVE
ACROSS OUR REGION...AS THE WARM FRONT SLOWLY LIFTS NORTHWARD.
SHOWERS WILL GENERALLY BE LIGHT TO MODERATE IN INTENSITY.
BY THE MID MORNING HOURS...THE WARM FRONT WILL BE LIFTING NORTH
ACROSS OUR NORTHERN ZONES. THERE STILL MAY BE SOME SHOWERS WITH
THE FRONT ACROSS OUR NORTHERN AREAS...OTHERWISE...THERE WILL BE A
LULL IN THE ACTIVITY ACROSS OUR AREA. SOME BREAKS OF SUN MAY START
TO DEVELOP...ESP FOR VALLEY AREAS FROM THE CAPITAL REGION ON
SOUTH. WITH A LIGHT S-SW WIND IN PLACE...DEWPOINTS WILL CONTINUE
TO RISE INTO THE LOWER TO MID 60S F.
BY AFTERNOON...A SHORTWAVE TROUGH WILL BE MOVING ACROSS THE TOP OF
DEVELOPING RIDGE ACROSS THE EASTERN CONUS...MOVING FROM THE GREAT
LAKES AND LOWER ONTARIO INTO UPSTATE NY. THIS SHORTWAVE...AIDED BY
A STRONG 30-40 KTS LOW LEVEL JET AT 850 HPA WILL HELP FIRE
CONVECTION IN THE WARM SECTOR.
THE NAM12...LOCAL HIRES WRF AND 3KM HRRR ALL SHOW
CONVECTION DEVELOPING ACROSS WESTERN AND CENTRAL NY DURING THE
EARLY AFTN. THIS ACTIVITY WILL SPREAD INTO OUR AREA FOR THE MID
THROUGH THE EVENING HOURS.
THERE ARE SEVERAL FACTORS WHICH POINT TO THE POTENTIAL FOR SEVERE
THUNDERSTORMS. BECAUSE OF THE STRENGTH OF THE LLJ...0-6 KM BULK SHEAR
WITH BE AROUND 30-40 KTS. 0-3 KM HELICITY VALUES ARE EXPECTED TO
BE AROUND 200 M2/S2 AND 0-1 KM HELICITY VALUES ARE ALSO VERY
IMPRESSIVE...WITH 100-200 M2/S2 BY EVENING. WHILE MID LEVEL LAPSE
RATES AREN/T OVERLY STRONG...VALUES OF 6-6.5 DEGREES C/KM WILL BE
SUFFICIENT FOR PRODUCING UPDRAFTS CAPABLE OF SEVERE WIND/HAIL.
WHILE THE MAIN THREAT WILL BE DAMAGING WINDS...THE IMPRESSIVE
HELICITY VALUES AND THE FACT THAT THIS SAME SYSTEM PRODUCED
TORNADOES LAST EVENING JUST UPSTREAM ACROSS LOWER MICHIGAN WOULD
POINT TO THE POTENTIAL FOR AN ISOLATED TORNADO OR TWO. THE
NAM12/GFS/AND ECMWF ALL DID SHOW SIGNIFICANT TORNADO PARAMETERS IN
EXCESS OF 1 AT SOME LOCATION IN OUR AREA...SO THE TORNADIC
POTENTIAL SHOULD NOT BE IGNORED. SPC AGREES WITH THIS ASSESSMENT
AND HAS OUR AREA IN A SLIGHT RISK...WITH A 5% PROBABILITY FOR A
TORNADO WITHIN 25 MI OF ANY PARTICULAR LOCATION.
THE MAIN INHIBITING FACTOR WILL BE HAVING ENOUGH INSTABILITY.
THERE ARE PLENTY OF CLOUDS AROUND...EVEN UPSTREAM IN THE WARM
SECTOR WITH LINGERING DEBRIS CLOUDS. IF ENOUGH INSTABILITY ISN/T
REALIZED...STORMS MAY HAVE A DIFFICULT TIME GROWING VERY
TALL...AND THE SEVERE POTENTIAL WOULD BE MINIMIZED. AT THIS
POINT...ALL MODELS SHOW CAPE VALUES OF 1000-1500 J/KG...BUT THE
POTENTIAL FOR SUFFICIENT SURFACE BASED CAPE WILL HAVE TO BE
MONITORED THROUGH THE MORNING HOURS.
MAX TEMPS WILL RANGE FROM THE MID 70S TO LOW 80S. IF MORE CLEARING
OCCURS...MAX TEMPS COULD WIND UP ON THE WARMER END OF THIS
RANGE...ESP FROM THE CAPITAL REGION ON SOUTH.
WITH THE LOSS OF HEATING...AND WITH THE SHORTWAVE MOVING TO THE
EAST OF THE AREA...THUNDERSTORM POTENTIAL WILL DIMINISH BY LATE
THIS EVENING. IT SHOULD CLEAR OUT...ALTHOUGH THERE WILL BE
POTENTIAL FOR PATCHY FOG IN THOSE AREAS THAT RECEIVE RAINFALL. MIN
TEMPS WILL BE IN THE 50S TO LOW 60S.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
WARM AND MUGGY WEATHER IS EXPECTED FOR THE SHORT TERM PERIOD AS
OUR REGION WILL BE DOMINATED BY A STRONG RIDGE AT 500 HPA CENTERED
OVER THE MID ATLANTIC REGION. 850 HPA TEMPS WILL SURGE TO 16-18
DEGREES C...SO MAX TEMPS WILL REACH THE UPPER 80S TO LOW 90S FOR
BOTH THURSDAY AND FRIDAY. OVERNIGHT LOWS WILL BE WARM AND
STICKY...WITH MAINLY UPPER 50S TO MID 60S AT NIGHT.
WHILE IT SHOULD BE WARM ENOUGH ALOFT TO KEEP A CAP ON ANY
CONVECTION...WE WILL GO WITH A SLIGHT CHC FOR A SHOWER OR
THUNDERSTORM ON THURSDAY AFTN IN CASE ANYTHING IS ABLE TO DEVELOP.
FRIDAY LOOKS EVEN MORE CAPPED...SO WE WILL KEEP THE FORECAST
COMPLETELY DRY FOR FRIDAY WITH A MOSTLY SUNNY TO PARTLY SUNNY SKY.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
HEAT CONTINUES INTO THE FIRST PART OF THE WEEKEND WITH HIGHS
SATURDAY WELL IN THE 80S TO NEAR 90. COLD FRONT AND AMPLIFYING
NORTHERN STREAM UPPER ENERGY APPROACH SUNDAY...TRACKING THROUGH OUR
REGION THE BEGINNING OF THE WEEK...WITH EXACT TIMING TO BE
DETERMINED. SINCE THE EXACT TIMING IS UNKNOWN...INCREASING CHANCES
FOR SHOWERS AND THUNDERSTORMS SUNDAY AND SUNDAY NIGHT...BUILDING
INTO THE MID HUDSON VALLEY AND WESTERN NEW ENGLAND LATER SUNDAY
NIGHT AND MONDAY. DRYING AND COOLING EXPECTED ONCE THE FRONT
EXITS...MONDAY NIGHT AND TUESDAY.
SOME STRONG THUNDERSTORMS ARE POSSIBLE SUNDAY AFTERNOON THROUGH
MONDAY AFTERNOON..DEPENDING ON THE EXACT TIMING OF THE FRONT. THERE
IS A DECENT CONSENSUS FOR A NOTICEABLE COOL DOWN AFTER THE FRONTAL
PASSAGE. HIGHS SUNDAY IN THE UPPER 70S TO MID 80S...COOLING TO HIGHS
IN THE UPPER 60S TO MID 70S MONDAY AND MID 60S TO LOWER 70S TUESDAY.
&&
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
AN AREA OF SHOWERS ASSOCIATED WITH AN OLD WEAKENING CONVECTIVE
COMPLEX SHOULD TRACK THROUGH THE REGION THROUGH ABOUT 10Z...REDUCING
CEILINGS AND VISIBILITIES TO PERIODS OF MVFR AND IFR. IFR
CONDITIONS SHOULD DOMINATE AT KPOU AND KPSF WITH MVFR AT KALB AND
KGFL...BUT ALL SITES SHOULD HAVE PERIODS OF MVFR AND IFR.
ONCE THIS AREA OF SHOWERS EXITS...SOME LINGERING LOW CLOUDS IN THE
IFR/MVFR RANGE AND VISIBILITIES LIKELY IN THE MVFR RANGE...SHOULD
CONTINUE THROUGH ABOUT 14Z. CEILINGS AND VISIBILITIES SHOULD BE
MAINLY VFR AFTER 14Z...THROUGH THE AFTERNOON AND IN TO THE EVENING
AS A WARM FRONT TRACKS THROUGH THE REGION. HOWEVER...THERE ARE
INDICATIONS THAT SOME ORGANIZED THUNDERSTORM ACTIVITY COULD TRACK
THROUGH THE REGION DURING THE AFTERNOON. KEEPING THE PROB30
INDICATIONS FOR THUNDERSTORMS BECAUSE THERE ARE ABOVE NORMAL CHANCES
FOR THUNDERSTORMS...ALTHOUGH SCATTERED...STILL ABOVE NORMAL CHANCES.
INDICATING MVFR CEILINGS AND VISIBILITIES IN THUNDERSTORMS FOR
NOW...BUT THERE COULD BE IFR FOR BRIEF PERIODS IN ANY THUNDERSTORMS.
THE ORGANIZED THUNDERSTORM ACTIVITY COULD MOVE OUT DURING THE EARLY
EVENING...SO JUST INDICATING VCSH AFTER 23Z...WITH VFR CONDITIONS AS
THE WARM FRONT SHOULD BE EXITING AND THE WARM SECTOR EXPANDS OVER
THE REGION.
VARIABLE MAINLY SOUTHEAST TO SOUTHWEST WINDS AT LESS THAN 10 KT
THROUGH THE EARLY MORNING...BECOMING SOUTH TO SOUTHWEST AROUND 10 KT
AFTER 14Z...THEN TRENDING MORE SOUTHWEST AT LESS THAN 10 KT BY THIS
EVENING. A STEADY LIGHT WIND THIS EVENING MAY PREVENT ANY FOG FROM
FORMING AFTER ANY THUNDERSTORM ACTIVITY EXITS...BUT TOO EARLY TO
TELL WHEN STORMS WILL EXIT AND HOW MUCH WIND THERE WILL BE ONCE WE
BREAK INTO THE WARM SECTOR.
OUTLOOK...
THU-SUN...VFR/MVFR. CHC PM -TSRA EACH DAY. LATE NIGHT AND/OR
EARLY MORNING MVFR/IFR ASSOC WITH FOG POSSIBLE.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS OVER THE NEXT SEVERAL DAYS. A WETTING
RAINFALL OCCURRED IN MOST AREAS EARLY THIS MORNING AND ADDITIONAL
SHOWERS AND THUNDERSTORMS ARE POSSIBLE TODAY INTO THIS EVENING.
RH VALUES WILL ONLY DROP TO 55 TO 70 PERCENT TODAY. S-SW WINDS AT
5-15 MPH ARE EXPECTED TODAY.
W-SW WINDS WILL BE AROUND 5-10 MPH TONIGHT WITH RH VALUES RECOVERING TO
NEAR 100 PERCENT. AN ISOLATED SHOWER OR THUNDERSTORM IS POSSIBLE
TOMORROW WITH RH VALUES DROPPING 40 TO 55 PERCENT TOMORROW AFTERNOON.
&&
.HYDROLOGY...
NO WIDESPREAD HYDROLOGIC CONCERNS OVER THE NEXT FIVE DAYS ACROSS
THE HSA.
SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS THE REGION TODAY. PWAT
VALUES WILL BE ABOVE NORMAL...WITH VALUES UP TO 1.75 INCHES...SO
ANY SHOWER OR THUNDERSTORM IS CAPABLE OF PRODUCING TORRENTIAL
DOWNPOURS. ALTHOUGH WIDESPREAD RIVER FLOODING IS NOT
EXPECTED...SMALL STREAM...POOR DRAINAGE...OR URBAN FLOODING WILL
BE POSSIBLE DEPENDING ON THE EXACT TRACK OF SHOWERS AND
THUNDERSTORMS...ESPECIALLY IF SEVERAL THUNDERSTORMS TRACK OVER THE
SAME LOCATION. 3 HR FFG FROM THE NERFC IS AROUND 2-3 INCHES.
ISOLATED SHOWERS OR THUNDERSTORMS ARE POSSIBLE ON THURSDAY
AFTERNOON. OTHERWISE...IT WILL BE FAIRLY DRY THROUGH THE END OF
THE WORK WEEK. ADDITIONAL SHOWERS OR THUNDERSTORMS ARE POSSIBLE
OVER THE WEEKEND.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS
SHORT TERM...FRUGIS
LONG TERM...NAS
AVIATION...NAS
FIRE WEATHER...FRUGIS
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS ALBANY NY
138 AM EDT WED MAY 29 2013
.SYNOPSIS...
RAIN AND SOME THUNDERSTORMS ASSOCIATED WITH A WARM FRONT
WILL MOVE THROUGH THE REGION FROM THE SOUTHWEST OVERNIGHT INTO
WEDNESDAY MORNING. AS AN UPPER LEVEL DISTURBANCE MOVES CLOSE TO THE
REGION...SOME STRONG THUNDERSTORMS ARE POSSIBLE ON WEDNESDAY
AFTERNOON INTO WEDNESDAY EVENING. MUCH WARMER TEMPERATURES AND
MUGGY CONDITIONS ARE EXPECTED FOR THE REMAINDER OF THE WEEK...WITH
SOME ADDITIONAL THUNDERSTORMS POSSIBLE OVER THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 138 AM EDT...A BAND OF RAIN SHOWERS AND EMBEDDED
THUNDERSTORMS ASSOCIATED WITH A WARM FRONT IS MOVING ACROSS
CENTRAL AND SOUTHERN PORTIONS OF THE CWA EARLY THIS MORNING.
RAINFALL IS GENERALLY LIGHT TO MODERATE...WITH ONE HOUR
ACCUMULATION ESTIMATES OF LESS THAN A QUARTER OF AN INCH PER HOUR.
OUR 4KM HIRES WRF AND THE 3KM HRRR ALL SHOW THIS ACTIVITY SLIDING
WEST TO EAST OVER THE NEXT FEW HOURS. BY LATE TONIGHT...THE BEST
THREAT FOR RAIN AND EMBEDDED THUNDER WILL BE ACROSS NORTHERN PARTS
OF THE CWA...AS THE WARM FRONT GRADUALLY MAKES NORTHWARD PROGRESS.
THUNDER WILL BE FAIRLY ISOLD TO SCATTERED OVERNIGHT...AS THERE IS
NO SURFACE INSTABILITY IN PLACE...AND ANY INSTABILITY WILL BE
ELEVATED AND FAIRLY LIMITED. WHILE THERE WERE SOME SEVERE TSTMS
ACROSS WESTERN NY/NORTHWEST PA...THERE WILL BE NO THREAT FOR
SEVERE STORMS WILL ANY OF THESE EMBEDDED THUNDERSTORMS OVERNIGHT.
THIS WILL BE DIFFERENT DURING THE WEDNESDAY /SEE THE SHORT TERM
SECTION FOR DETAILS ON THE SEVERE POTENTIAL FOR THE AFTN TO EVE
HOURS/.
WITH THE CLOUDS...PRECIP...AND LIGHT SOUTHERLY WINDS...TEMPS
OVERNIGHT WILL GENERALLY HOLD STEADY IN THE MID 50S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM THURSDAY/...
OUR REGION WILL BE SITUATED ON THE NORTHERN FRINGE OF A BUILDING
RIDGE ACROSS THE EASTERN CONUS ON WEDNESDAY. AT THE SFC...WE WILL
BE POKING INTO THE WARM SECTOR AS THE WARM FRONT WILL BE LIFTING
ACROSS THE REGION. THE WARM FRONT WILL BE MOVING ACROSS THE THE
REGION WEDNESDAY MORNING...SO HAVE CONTINUED LIKELY POPS FOR A FEW
HOURS...ESPECIALLY ACROSS THE NORTH.
AFTERWARD...SOME BREAKS OF SUN WILL OCCUR...ESP FOR VALLEY AREAS.
A SHORTWAVE WILL BE MOVING WITHIN THE STRONG W-SW FLOW ALOFT
ACROSS ONTARIO TOWARDS NORTHERN NY FOR THE AFTN HOURS. THE AMOUNT OF
SUNSHINE THAT OCCURS WILL BE CRITICAL...AS THIS WILL DETERMINE JUST
HOW MUCH INSTABILITY CAN BUILD UP. MODELS SHOW SHEAR VALUES BETWEEN
30 AND 40 KTS...AND CAPE VALUES OF 500-1500 J/KG. SPC CONTINUES TO
HAS PLACE OUR REGION IN A SLIGHT RISK FOR SEVERE WX AND HAS EVEN
EXPANDED THE SIZE OF THE AREA...AND IT APPEARS THAT WE WILL HAVE
SEVERAL INGREDIENTS IN PLACE FOR SOME GUSTY TSTMS.
HAVE 40 TO 50 PERCENT FOR SHOWERS/TSTMS. HAVE TRENDED MAX TEMPS
TOWARDS THE WARMER MAV GUIDANCE WITH HIGHS IN THE MID 70S TO MID
80S.
THE CHANCE FOR TSTMS WILL BE DECREASING TO ONLY SLIGHT CHANCE LATE
WEDNESDAY NIGHT AS THE SHORTWAVE MOVES EASTWARD...AND SFC HEATING
DIMINISHES. LOWS WILL BE IN THE MID 50S TO MID 60S.
850 HPA WILL RISE TO 16-18 DEGREES C ON THURSDAY...WITH THE 500 HPA
RIDGE CENTERED OVER THE DELMARVA. IT WILL BE WARM AND MUGGY...WITH
MAX TEMPS IN THE UPPER TO LOWER 90S. THE SFC BOUNDARY SHOULD BE
LOCATED FAR ENOUGH TO NORTH OF THE AREA FOR LITTLE LARGE SCALE
FORCING TO BE IN PLACE ACROSS OUR AREA...SO WIDESPREAD CONVECTION IS
NOT ANTICIPATED. MOST AREAS WILL LIKELY BE CAPPED AS WELL. HAVE
ONLY FORECAST A SLIGHT CHANCE OF TSTMS DURING THE AFTERNOON.
WITH THE RIDGE AND STRONG CAP STILL OVER THE REGION THURSDAY
NIGHT...HAVE NOT FORECAST ANY PCPN. IT WILL REMAIN WARM AND MUGGY
WITH LOWS IN THE UPPER 50S TO MID 60S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
THE LONG TERM WILL BE CHARACTERIZED BY INCREASING TEMPERATURES AND
HUMIDITY ALONG WITH CHANCES FOR SHOWERS AND THUNDERSTORMS AS A COLD
FRONT CROSSES THE REGION DURING THE WEEKEND.
LONG RANGE GUIDANCE CONTINUES TO BE IN EXCELLENT AGREEMENT HANDLING
MUCH OF THE LONG TERM PERIOD WITH BOTH THE 12Z GFS/ECMWF AND VARIOUS
ENSEMBLE MEMBERS DEPICTING A LARGE WARM CORE HIGH ACROSS THE EASTERN
THIRD OF THE NATION. THIS SYNOPTIC SETUP WILL BE PREVALENT THROUGH
MUCH OF THE FIRST WEEKEND OF JUNE...ALLOWING FOR A PERSISTENT
SOUTHWESTERLY RETURN FLOW TRANSPORT OF WARM AND HUMID AIR ACROSS THE
REGION AS MANY LOCATIONS ACROSS THE FORECAST AREA LOOK TO REACH 90
DEGREES FOR THE FIRST TIME IN 2013 ON FRIDAY.
A PATTERN SHIFT WILL START TO SLOWLY TAKE PLACE BEGINNING
SATURDAY...AS AN UPPER-LEVEL TROUGH AND ASSOCIATED SURFACE LOW
PRESSURE SYSTEM AND COLD FRONT APPROACH FROM THE UPPER MIDWEST. WITH
THE LARGE ANTICYCLONIC BERMUDA CIRCULATION FIRMLY ENTRENCHED ACROSS
THE EASTERN CONUS AND A POSITIVE-TILT ORIENTATION TO THE UPSTREAM
TROUGH...THERE REMAINS SOME UNCERTAINTY REGARDING THE EXACT TIMING
OF THE COLD FRONTAL PASSAGE ACROSS THE FORECAST AREA.
REGARDLESS...HAVE INTRODUCED SLIGHT CHANCE POPS BEGINNING EARLY
SATURDAY AS SOME WEAK NORTHERN STREAM ENERGY SLIDES OFF TO THE
NORTH. POPS INCREASE SATURDAY NIGHT TO CHANCE...WITH LIKELY POPS FOR
MUCH OF THE FORECAST AREA SUNDAY.
GIVEN ANTECEDENT WARM AND HUMID CONDITIONS AHEAD OF THE COLD FRONT
AND SHOWALTER INDICES BELOW 0C COUPLED WITH INCREASING WIND PROFILES
FROM A 50-70 KNOT UPPER-LEVEL JET...THE POTENTIAL EXISTS FOR
STRONGER STORMS SUNDAY ACCOMPANYING THE COLD FRONT PASSAGE.
THE QUESTION WILL BE JUST HOW MUCH INSTABILITY THERE WILL BE
SUNDAY...BUT THERE CONTINUES TO BE A SIGNAL FOR MORE ROBUST
CONVECTION. WITH 850 HPA MOISTURE TRANSPORT VECTORS INDICATING RAPID
MOISTURE TRANSPORT INTO THE REGION AMIDST PWAT ANOMALIES OF 1-2
STANDARD DEVIATIONS...THE POTENTIAL ALSO EXISTS FOR SOME TORRENTIAL
RAINFALL WITH ANY CONVECTION THAT DEVELOPS.
THE COLD FRONT WILL CROSS THE FORECAST AREA SOMETIME IN THE LATE
SUNDAY-EARLY MONDAY TIMEFRAME...ENDING PRECIPITATION CHANCES ACROSS
MUCH OF THE FORECAST AREA. IT IS DURING THIS TIMEFRAME THAT THE LONG
RANGE GUIDANCE BEGINS TO DIVERGE WITH THE 12Z GFS CONTINUING TO
INDICATE THE FRONT STALLING SOMEWHERE ALONG THE EASTERN SEABOARD
WITH A WAVE OF LOW PRESSURE DEVELOPING ALONG IT DUE TO THE
AMPLIFICATION OF THE UPPER TROUGH...WHILE THE 12Z ECMWF MAINTAINS A
PROGRESSIVE POSITIVE-TILT ORIENTATION TO THE UPPER TROUGH. GIVEN THE
SOUTHWARD DISPLACEMENT OF THE BERMUDA HIGH...WILL SIDE WITH THE 12Z
ECMWF SOLUTION FAVORING DECREASING PRECIPITATION CHANCES VERSUS A
POTENTIAL HEAVY RAIN EVENT ACCORDING TO THE GFS FOR EARLY NEXT WEEK.
WITH HUMID CONDITIONS IN PLACE...THE FIRST WEEKEND OF JUNE WILL FEEL
A LOT LIKE THE DOG DAYS OF SUMMER AS HIGH TEMPERATURES FRIDAY AND
SATURDAY REACH WELL INTO THE 80S...WITH POCKETS OF NEAR 90 AND
POTENTIALLY EVEN LOW 90S IN THE MID HUDSON VALLEY. THE RECORD HIGH
FOR ALBANY ON FRIDAY IS 92 DEGREES SET IN 1937 AND 94 DEGREES ON
SATURDAY SET IN 1918. TEMPERATURES WILL REMAIN IN THE 80S FOR SUNDAY
AHEAD OF THE COLD FRONT. THE PASSAGE OF THE COLD FRONT WILL USHER IN
CANADIAN HIGH PRESSURE AND COOLER TEMPERATURES...WITH HIGHS IN THE
UPPER 60S/LOWER 70S FOR THE START OF NEXT WEEK. LOW TEMPERATURES
WILL GENERALLY BE IN THE UPPER 50S TO MID 60S BEFORE COOLING INTO
THE UPPER 40S-MID 50S FOR THE START OF NEXT WEEK.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AN AREA OF SHOWERS ASSOCIATED WITH AN OLD WEAKENING CONVECTIVE
COMPLEX SHOULD TRACK THROUGH THE REGION THROUGH ABOUT 10Z...REDUCING
CEILINGS AND VISIBILITIES TO PERIODS OF MVFR AND IFR. IFR
CONDITIONS SHOULD DOMINATE AT KPOU AND KPSF WITH MVFR AT KALB AND
KGFL...BUT ALL SITES SHOULD HAVE PERIODS OF MVFR AND IFR.
ONCE THIS AREA OF SHOWERS EXITS...SOME LINGERING LOW CLOUDS IN THE
IFR/MVFR RANGE AND VISIBILITIES LIKELY IN THE MVFR RANGE...SHOULD
CONTINUE THROUGH ABOUT 14Z. CEILINGS AND VISIBILITIES SHOULD BE
MAINLY VFR AFTER 14Z...THROUGH THE AFTERNOON AND IN TO THE EVENING
AS A WARM FRONT TRACKS THROUGH THE REGION. HOWEVER...THERE ARE
INDICATIONS THAT SOME ORGANIZED THUNDERSTORM ACTIVITY COULD TRACK
THROUGH THE REGION DURING THE AFTERNOON. KEEPING THE PROB30
INDICATIONS FOR THUNDERSTORMS BECAUSE THERE ARE ABOVE NORMAL CHANCES
FOR THUNDERSTORMS...ALTHOUGH SCATTERED...STILL ABOVE NORMAL CHANCES.
INDICATING MVFR CEILINGS AND VISIBILITIES IN THUNDERSTORMS FOR
NOW...BUT THERE COULD BE IFR FOR BRIEF PERIODS IN ANY THUNDERSTORMS.
THE ORGANIZED THUNDERSTORM ACTIVITY COULD MOVE OUT DURING THE EARLY
EVENING...SO JUST INDICATING VCSH AFTER 23Z...WITH VFR CONDITIONS AS
THE WARM FRONT SHOULD BE EXITING AND THE WARM SECTOR EXPANDS OVER
THE REGION.
VARIABLE MAINLY SOUTHEAST TO SOUTHWEST WINDS AT LESS THAN 10 KT
THROUGH THE EARLY MORNING...BECOMING SOUTH TO SOUTHWEST AROUND 10 KT
AFTER 14Z...THEN TRENDING MORE SOUTHWEST AT LESS THAN 10 KT BY THIS
EVENING. A STEADY LIGHT WIND THIS EVENING MAY PREVENT ANY FOG FROM
FORMING AFTER ANY THUNDERSTORM ACTIVITY EXITS...BUT TOO EARLY TO
TELL WHEN STORMS WILL EXIT AND HOW MUCH WIND THERE WILL BE ONCE WE
BREAK INTO THE WARM SECTOR.
OUTLOOK...
THU-SUN...VFR/MVFR. CHC PM -TSRA EACH DAY. LATE NIGHT AND/OR
EARLY MORNING MVFR/IFR ASSOC WITH FOG POSSIBLE.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS OVER THE NEXT SEVERAL DAYS.
S-SE WINDS WILL BE AROUND 5 TO 15 MPH TONIGHT WITH RH VALUES
RECOVERING TO NEAR 100 PERCENT. SHOWERS AND THUNDERSTORMS ARE LIKELY
TONIGHT AND WEDNESDAY. ALSO ON WEDNESDAY...RH VALUES WILL ONLY DROP
TO BETWEEN 50 AND 65 PERCENT WITH S-SW WINDS AT 10 TO 20 MPH WITH
GUSTS OVER 25 MPH.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE EXPECTED ACROSS THE HSA FOR THE
NEXT 5 DAYS.
RIVER FLOWS HAVE RECEDED THE PAST FEW DAYS AFTER THE HEAVIER RAINS
FROM LAST WEEK INTO THE WEEKEND. AN APPROACHING WARM FRONT WILL
ALLOW FOR SOME SHOWERS AND POSSIBLE THUNDERSTORMS INTO WEDNESDAY
MORNING. ADDITIONAL THUNDERSTORMS ARE POSSIBLE ON WEDNESDAY...WITH
JUST ISOLATED TO WIDELY SCATTERED THUNDERSTORM ACTIVITY ON THURSDAY
THROUGH SATURDAY.
WHILE WIDESPREAD HEAVY RAINFALL IS NOT ANTICIPATED THIS WEEK...ANY
AREAS THAT SEES REPEATED SHOWERS OR THUNDERSTORMS MAY LOCALLY SEE
SOME WITHIN BANK RISES ON RIVERS AND STREAMS. DUE TO THE SCATTERED
NATURE OF THE SHOWERS AND THUNDERSTORMS...QPF AMOUNTS WILL BE
VARIABLE ACROSS THE REGION. THE LATEST WEATHER PREDICTION CENTER
/WPC/ QPF FORECAST CALLS FOR UP TO AN INCH OF RAINFALL ACROSS THE
REGION THROUGH SATURDAY EVENING...ALTHOUGH THIS WILL ULTIMATELY
DEPEND ON THE EXACT TRACK OF ANY SHOWERS OR THUNDERSTORMS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS
SHORT TERM...FRUGIS/GJM
LONG TERM...IRL
AVIATION...NAS
FIRE WEATHER...GJM
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
351 AM EDT WED MAY 29 2013
.SYNOPSIS...
A WARM FRONT WILL CONTINUE TO LIFT NORTHWARD THROUGH TODAY AS AN
AREA OF HIGH PRESSURE OFF THE EASTERN SEABOARD SPREADS ITS INFLUENCE
INTO THE MID ATLANTIC REGION, BRINGING INCREASING HEAT AND HUMIDITY
TO THE AREA THROUGH THIS WEEKEND. FOR EARLY NEXT WEEK, A LOW
PRESSURE SYSTEM EMERGING FROM AROUND THE GREAT LAKES WILL SEND A
COLD FRONT THROUGH OUR REGION BY MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A WARM FRONT IS DRAPED ACROSS SOUTHERN NEW JERSEY AND NORTH/CENTRAL
DELMARVA EARLY THIS MORNING. NORTH OF THE BOUNDARY, LOW CLOUDS AND
DENSE FOG WILL PERSIST, WHILE SOUTH OF THE FRONT, WE DO NOT EXPECT
FOG TO DEVELOP UNTIL OVERNIGHT.
SHOWERS DIMINISHING IN THEIR EASTWARD PROGRESS ACROSS N PA AT THE
VERY WORST WILL JUST SKIM MOUNT POCONO AND HIGH POINT BETWEEN 3 AM
AND 6 AM.
THE PAST TWO CYCLES OF THE SPCWRF HAD WHAT I THOUGHT WERE EXCELLENT
HOURLY RADAR SIMULATIONS OF WHAT HAS TRANSPIRED FROM LERIE TO THE
DELMARVA INCLUDING OUR FORECAST AREA. THAT SPCWRF IS RELIED ON
HEAVILY AGAIN FOR THE UPCOMING FORECAST FOR TODAY AND TONIGHT.
TODAY...THE 00Z/29 VERSION OF THE SPCWRF IS MORE VIGOROUS ACROSS
OUR AREA THIS AFTN/EVENING THAN I ANTICIPATED. STILL NOT QUITE
SURE IF TWO BANDS OF DECENT CONVECTION CAN DEVELOP SEWD ACROSS
OUR FCST AREA...THE FIRST FROM KDCA-KBLM AROUND 21Z AND WEAKENING
ESEWD OVER FAR SNJ NEAR SUNSET.
THE MORE SIGNIFICANT BAND OF STRONG STORMS WILL PROBABLY DEVELOP
NEAR THE NY/PA BORDER MID AFTN AND ORGANIZE ESEWD TO NEAR I80 BY
AROUND 8 PM EDT. GFS ML CAPE WILL RISE TO NEAR 1500J ALONG I95 THIS
AFTN. THIS SUPPLIES DECENT ENERGY FOR CONVECTION PROVIDED ITS NOT
TOO DRY ALOFT AND THAT THERE CAN BE SOME SORT OF BOUNDARY TRIGGERING
AND ORGANIZING THE CONVECTION.
NOT MUCH 0-6KM BULK SHEAR SUPPORT FOR SVR WIND IN OUR AREA BUT A
GUSTY NW WIND OUTFLOW OF 35-40 KT IS POSSIBLE FROM KMPO TO KFWN
AND POSSIBLY DOWN TO KRDG/KABE AND KTTN. ADDITIONALLY TT UP AROUND
50C HAS ME A LITTLE CONCERNED BUT ON THE OTHER SIDE OF THE COIN...KI
IS NOT MUCH LARGER THAN 30-32C IN THE BAND SO AM NOT CONVINCED THAT
THE SPC WRF VIGOR WILL BE REALIZED. NEVERTHELESS...THIS MODEL HAS
GARNERED MY RESPECT SINCE ITS GENERALLY A SUCCESSFUL SIMULATOR OF
THE FUTURE REALITY.
SINCE THE NAM SPITS OUT QPF PRIOR TO 18Z...THAT TRIMS ITS BL TEMP AND
2M TEMPS BY 1-3 DEGS AND WE SEE THE DRY RAP MODEL FCSTG LOWER 90S
19Z-22Z FOR S NJ AND THE PHILLY AREA. THAT MIGHT BE 2 DEGS TO HIGH
FOR 15C AT 850 BUT ITS QUITE POSSIBLE THAT 90F WILL OCCUR AND THAT
OUR HEAT WAVE BEGINS AROUND 3-4PM THIS AFTN.
GRADIENT SW WIND GUST 15-20 MPH THIS AFTN. COOLING SEA BREEZES
WILL STRUGGLE TO PENETRATE INLAND IN THIS GRADIENT FLOW BEHIND THE
WFRONT AND EVEN KACY SHOULD REACH 90F WITH ONLY THE NEAREST 3MI OF
THE COAST RECEIVING THE BENEFIT OF COOLING SLY OCEAN BREEZES.
SINCE OUR HI IS BELOW 96. NO HEAT ADVY NOR EXCESSIVE HEAT WATCHES
BUT EMERGENCY MANAGEMENT HAS BEEN BRIEFED ON THE PROBABLE 3-5 DAY
EARLY SEASON HEAT WAVE FOR THE I95 CORRIDOR.
GENERALLY 50 50 BLENDED GFS NAM GUIDANCE BUT USED THE WARMER 2M
TEMPS FROM THE NAM/RGEM AND RAP-RUC TO MODIFY THE PCPN TAINTED NAM
MOS OUTPUT.
PHL AROUND 89 TODAY AND 90-91 IN SNJ EVEN TO KACY AND S DE VCNTY KGED.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
THE LAST BAND OF WHATEVER HEAVY CONVECTION IS PRESSED ESEWD FROM
VCNTY KRDG-KTTN AT AROUND 00-01Z AND WEAKEN JUST TO THE N OF KPNE
AND KACY AROUND 03Z. OTRW A WARM SUMMERLIKE NIGHT.
50 50 BLENDED 00Z/29 GFS/NAM GUIDANCE.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
TO START THE LONG TERM, SURFACE HIGH PRESSURE WILL BE FOUND OVER THE
CENTRAL ATLANTIC, EXTENDING ITS INFLUENCE WESTWARD INTO THE MIDDLE
ATLANTIC STATES. MEANWHILE, STRONG MID-LEVEL RIDGING WILL ALSO BE
TAKING HOLD ACROSS THE REGION. THIS LOOKS TO BE THE BEGINNING OF OUR
FIRST POTENTIAL HEAT WAVE OF THE SEASON, AS A STRENGTHENING
SOUTHWESTERLY FLOW THROUGH THE END OF THE WORK WEEK AND INTO THE
WEEKEND WILL BRING INCREASING HEAT AND HUMIDITY. MODEL 850MB AND
925MB TEMPS SUPPORT MAXIMUM TEMPERATURES EASILY REACHING THE UPPER
80S TO LOWER 90S ACROSS MOST OF THE FORECAST AREA, WITH DEWPOINTS
CLIMBING INTO THE LOWER AND MIDDLE 60S. WE WILL CONTINUE A MENTION
OF THIS EXPECTED HEAT WAVE IN OUR HAZARDOUS WEATHER OUTLOOK, AS HEAT
INDEX VALUES LOOK TO RANGE BETWEEN 90 TO 95 DEGREES.
FOR THE LATTER PART OF THE WEEKEND INTO SUNDAY, THE SURFACE HIGH
PRESSURE AND THE MID-LEVEL RIDGE WILL BOTH BEGIN TO SHIFT EASTWARD,
AS LOW PRESSURE TAKES SHAPE AROUND THE GREAT LAKES WITH A TRAILING
COLD FRONT. WITH THE OVERALL PATTERN BEGINNING TO BREAK DOWN, MODEL
RELATIVE HUMIDITIES INDICATE INCREASING MOISTURE AND CLOUDINESS FOR
SUNDAY, WITH MAXIMUM TEMPERATURES MOSTLY IN THE MIDDLE TO UPPER 80S
ACROSS THE REGION. WE HAVE RETAINED INCREASING POPS FOR
SHWRS/T-STORMS FROM WEST TO EAST ACROSS THE FORECAST AREA DURING
SUNDAY AND SUNDAY NIGHT AS THERE LOOKS TO BE AMPLE INSTABILITY AHEAD
OF THE APPROACHING FRONT. MOST OF THE MODEL GUIDANCE HAS THE COLD
FRONT PASSING THROUGH THE REGION DURING MONDAY, ALTHOUGH THERE ARE
TIMING DIFFERENCES BETWEEN THE GFS, ECMWF, AND OTHERS. AT THIS
EXTENDED TIME RANGE, WE USED A BLEND OF WPC GUIDANCE WITH CONTINUITY
FOR MOST ELEMENTS, INCLUDING TEMPERATURES AND WINDS, AND WE KEPT
HIGH CHANCE POPS IN PLACE ACROSS THE REGION THROUGH MOST OF MONDAY.
WHILE THE FINER DETAILS WILL BE WORKED OUT AS WE GET CLOSER IN TIME
TO THE FRONTAL PASSAGE AND THE MODELS ALIGN MORE WITH REGARDS TO THE
TIMING OF THE FRONT, WHAT IS APPARENT IS THAT TEMPERATURES WILL
RETURN CLOSER TO SEASONAL AVERAGES FOR MONDAY AND TUESDAY.
&&
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THROUGH 12Z...IFR/LIFR CONDS IN ST/FOG MUCH OF E PA AND NNJ WITH
ISOLATED SHOWERS AND CALM WIND. FOR FAR S NJ AND DE...GENERALLY
OCNL MVFR VSBY IN FOG WITH S WIND.
AFTER 12Z...ANY REMAINING IFR/LIFR FOG/STRATUS QUICKLY DISSIPATES
BY 13Z AND BECOMES VFR SCT-BKN AOA 5000 FT WITH A SW WIND G15 KT
IN THE AFTN. TWO BANDS OF TSTMS ARE MODELED BY THE SPCWRF AS DISCUSSED
IN DETAIL IN OUR NEAR TERM SECTION. HAVE FOLLOWED THIS FOR THE 06Z
TAFS WITH SUPPORT FROM THE LATEST RAPRUC. IF THESE BANDS...ESPECIALLY
THE NRN PA-NNJ BAND DEVELOP...EXPECT A BRIEF 35-40 KT GUSTY NW
OUTFLOW FROM THE STORMS.
TONIGHT...A LINE OF DYING SHOWERS AND EMBEDDED TSTMS MAY SLIDE
ESEWD FROM VCNTY KRDG-KTTN AROUND 00Z DYING OUT NEAR KPNE-KACY
AROUND 03Z. OTRW VFR WITH POSSIBLE MVFR HAZE FOG TOWARD DAWN
THURSDAY.
OUTLOOK...
THURSDAY THROUGH SATURDAY...MAINLY VFR CONDITIONS EXPECTED WITH
SOUTHWESTERLY WINDS. SOME LOCAL REDUCED VSBYS POSSIBLE EACH MORNING
IN HAZE.
SUNDAY...MAINLY VFR CONDITIONS THROUGH THE DAY, WITH SUB-VFR
CONDITIONS POSSIBLE IN SHWRS/T-STORMS BY LATE-DAY AND INTO SUNDAY
NIGHT.
&&
.MARINE...
SEAS AND WINDS WERE FCST MUCH TOO HIGH ON THE ATLC WATERS TUE AFTN
AND 44009..WITH ITS WIND DATA PROBLEMS AND ALL..STILL BARELY JUST
MADE IT 5 FT AT 11PM EDT AND NOW AROUND 4FT. WILL DISCONTINUE THE
SCA FOR THE SNJ AND DE WATERS PROBABLY AT 6 AM IF NOT SOONER.
OTRW A GENERALLY SSW 10-20 KT FLOW PREVAILS TODAY AND TONIGHT WITH
NO HEADLINE. A BIT OF VSBY RESTRICTION IN FOG AND HAZE TIL 9 AM
EDT AND POSSIBLY IN HAZE EARLY THURSDAY MORNING. WINDS WILL PROBABLY
TURN SSE ALONG THE COASTS FOR A TIME THIS AFTN BUT EVEN THERE..THE
WSW GRADIENT FLOW MAY PREVENT MUCH OF AN EAST OF SOUTH TURN.
OUTLOOK...
WITH OFFSHORE HIGH PRESSURE INFLUENCING THE MID ATLANTIC REGION AND
OUR WATERS, SUB-SCA CONDITIONS ARE EXPECTED ON OUR WATERS FROM
THURSDAY THROUGH THE FIRST PART OF THE WEEKEND. WINDS THROUGH THIS
TIME FRAME WILL MAINLY BE OUT OF THE SOUTHWEST, WITH SEAS IN THE 3
TO 4 FOOT RANGE FOR OUR COASTAL WATERS AND 1 TO 3 FOOT SEAS IN
DELAWARE BAY. GOING INTO SUNDAY WITH HIGH PRESSURE DRIFTING FARTHER
EAST INTO THE CENTRAL ATLANTIC AND A COLD FRONT APPROACHING THE
REGION FROM THE WEST, WE EXPECT WIND GUSTS AND SEAS TO REACH SMALL
CRAFT ADVISORY LEVELS.
&&
.RIP CURRENTS...
RIP CURRENT AWARENESS WEEK JUNE 2 THROUGH 8.
PSA`S WILL AIR ON KPHI NWR AND POST DAILY AROUND 545 AM. A SHORT
AWARENESS PRESS CONFERENCE IN SURF CITY - LBI, TUE JUNE 4 2PM FOR
THOSE MEDIA REPRESENTATIVES THAT ARE INTERESTED IN RAISING RIP
CURRENT AWARENESS AND CONDITIONS FAVORING UNGUARDED LIFE THREATENING
DANGER IN THE OCEAN SURF ZONE.
MORE ON THIS IN THE AFD NEXT MONDAY JUNE 3.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...DENSE FOG ADVISORY UNTIL 7 AM EDT THIS MORNING FOR PAZ054-055-
060>062-071-101>106.
NJ...DENSE FOG ADVISORY UNTIL 7 AM EDT THIS MORNING FOR NJZ007>010-
015-019.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KLINE
NEAR TERM...DRAG
SHORT TERM...DRAG
LONG TERM...KLINE
AVIATION...DRAG/KLINE
MARINE...DRAG/KLINE
RIP CURRENTS...DRAG
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
210 AM EDT WED MAY 29 2013
.SYNOPSIS...
A WARM FRONT WILL LIFT NORTHEAST OF OUR REGION AROUND DAYBREAK.
THEREAFTER...HIGH PRESSURE WILL BE RIDGED FROM THE CENTRAL ATLANTIC
TO THE CAROLINAS LATER TODAY THROUGH THE WEEKEND PROVIDING A PROBABLE
EARLY SEASON HEAT WAVE OF 3 TO 5 DAYS. A LOW PRESSURE SYSTEM OVER
THE GREAT LAKES SUNDAY WILL MOVE TO QUEBEC WITH ITS COLD FRONT
TRAILING SOUTHWARD ALONG THE EAST COAST EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
A WARM FRONT IS DRAPED ACROSS SOUTHERN NEW JERSEY AND NORTH/CENTRAL
DELMARVA EARLY THIS MORNING. NORTH OF THE BOUNDARY, LOW CLOUDS AND
DENSE FOG WILL PERSIST, WHILE SOUTH OF THE FRONT, WE DO NOT EXPECT
FOG TO DEVELOP UNTIL OVERNIGHT.
SHOWERS DIMINISHING IN THEIR EASTWARD PROGRESS ACROSS N PA AT THE
VERY WORST WILL JUST SKIM MOUNT POCONO AND HIGH POINT BETWEEN 3 AM
AND 6 AM.
THE PAST TWO CYCLES OF THE SPCWRF HAD WHAT I THOUGHT WERE EXCELLENT
HOURLY RADAR SIMULATIONS OF WHAT HAS TRANSPIRED FROM LERIE TO THE
DELMARVA INCLUDING OUR FORECAST AREA. THAT SPCWRF IS RELIED ON
HEAVILY AGAIN FOR THE UPCOMING FORECAST FOR TODAY AND TONIGHT.
TODAY...THE 00Z/29 VERSION OF THE SPCWRF IS MORE VIGOROUS ACROSS
OUR AREA THIS AFTN/EVENING THAN I ANTICIPATED. STILL NOT QUITE
SURE IF TWO BANDS OF DECENT CONVECTION CAN DEVELOP SEWD ACROSS
OUR FCST AREA...THE FIRST FROM KDCA-KBLM AROUND 21Z AND WEAKENING
ESEWD OVER FAR SNJ NEAR SUNSET.
THE MORE SIGNIFICANT BAND OF STRONG STORMS WILL PROBABLY DEVELOP
NEAR THE NY/PA BORDER MID AFTN AND ORGANIZE ESEWD TO NEAR I80 BY
AROUND 8 PM EDT. GFS ML CAPE WILL RISE TO NEAR 1500J ALONG I95 THIS
AFTN. THIS SUPPLIES DECENT ENERGY FOR CONVECTION PROVIDED ITS NOT
TOO DRY ALOFT AND THAT THERE CAN BE SOME SORT OF BOUNDARY TRIGGERING
AND ORGANIZING THE CONVECTION.
NOT MUCH 0-6KM BULK SHEAR SUPPORT FOR SVR WIND IN OUR AREA BUT A
GUSTY NW WIND OUTFLOW OF 35-40 KT IS POSSIBLE FROM KMPO TO KFWN
AND POSSIBLY DOWN TO KRDG/KABE AND KTTN. ADDITIONALLY TT UP AROUND
50C HAS ME A LITTLE CONCERNED BUT ON THE OTHER SIDE OF THE COIN...KI
IS NOT MUCH LARGER THAN 30-32C IN THE BAND SO AM NOT CONVINCED THAT
THE SPC WRF VIGOR WILL BE REALIZED. NEVERTHELESS...THIS MODEL HAS
GARNERED MY RESPECT SINCE ITS GENERALLY A SUCCESSFUL SIMULATOR OF
THE FUTURE REALITY.
SINCE THE NAM SPITS OUT QPF PRIOR TO 18Z...THAT TRIMS ITS BL TEMP AND
2M TEMPS BY 1-3 DEGS AND WE SEE THE DRY RAP MODEL FCSTG LOWER 90S
19Z-22Z FOR S NJ AND THE PHILLY AREA. THAT MIGHT BE 2 DEGS TO HIGH
FOR 15C AT 850 BUT ITS QUITE POSSIBLE THAT 90F WILL OCCUR AND THAT
OUR HEAT WAVE BEGINS AROUND 3-4PM THIS AFTN.
GRADIENT SW WIND GUST 15-20 MPH THIS AFTN. COOLING SEA BREEZES
WILL STRUGGLE TO PENETRATE INLAND IN THIS GRADIENT FLOW BEHIND THE
WFRONT AND EVEN KACY SHOULD REACH 90F WITH ONLY THE NEAREST 3MI OF
THE COAST RECEIVING THE BENEFIT OF COOLING SLY OCEAN BREEZES.
SINCE OUR HI IS BELOW 96. NO HEAT ADVY NOR EXCESSIVE HEAT WATCHES
BUT EMERGENCY MANAGEMENT HAS BEEN BRIEFED ON THE PROBABLE 3-5 DAY
EARLY SEASON HEAT WAVE FOR THE I95 CORRIDOR.
GENERALLY 50 50 BLENDED GFS NAM GUIDANCE BUT USED THE WARMER 2M
TEMPS FROM THE NAM/RGEM AND RAP-RUC TO MODIFY THE PCPN TAINTED NAM
MOS OUTPUT.
PHL AROUND 89 TODAY AND 90-91 IN SNJ EVEN TO KACY AND S DE VCNTY KGED.
&&
.SHORT TERM /TONIGHT/...
THE LAST BAND OF WHATEVER HEAVY CONVECTION IS PRESSED ESEWD FROM
VCNTY KRDG-KTTN AT AROUND 00-01Z AND WEAKEN JUST TO THE N OF KPNE
AND KACY AROUND 03Z. OTRW A WARM SUMMERLIKE NIGHT.
50 50 BLENDED 00Z/29 GFS/NAM GUIDANCE.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
5-WAVE MODEL GUIDANCE SHOWS A RATHER LARGE BERMUDA RIDGE SETTING UP
THROUGH THE END OF THE WEEKEND WITH WEAK UPSTREAM TROUGHING. THE
RIDGE LOOKS TO AMPLIFY TOWARDS THE END OF THE WEEK BEFORE SHIFTING
MORE TOWARDS THE EAST-NORTHEAST. THE LONGWAVE TROUGH WILL BEGIN TO
FILL BACK IN BEHIND THE DEPARTING RIDGE BY EARLY NEXT WEEK.
WITH THE WARM FRONT PROGRESSING TO OUR NORTHEAST ON THURSDAY MORNING
AND WINDS BEGINNING TO BACK, WE SHOULD BE DRYING OUT THE COLUMN SOME
ALOFT. WITH VERY LITTLE IN THE WAY OF UPPER LEVEL SUPPORT AND
SURFACE RIDGING JUST TO OUR EAST WE KEEP THE FORECAST THROUGH THE
FIRST PART OF THE LONGTERM FAIRLY DRY. AN ENSUING VERY HOT AND HUMID
AIRMASS WILL MOVE IN STARTING ON THURSDAY WHICH LOOKS TO COMMENCE
OUR FIRST HEAT WAVE OF THE SEASON. SURFACE DEWPOINTS WILL CLIMB INTO
THE LOW TO MID-60S DURING THE HEAT WAVE UNDER AN INCREASING
SOUTHWESTERLY FLOW. THIS WOULD LEAD TO HEAT INDEX VALUES INTO THE
LOW-90S..CLOSER TO THE ACTUAL TEMPERATURES...NO HEAT RELATED
HEADLINES NEEDED THUS FAR. CLOSER TO THE COAST IT LOOKS DOUBTFUL
THAT A SEABREEZE WILL BE ABLE TO BRING ANY RELIEF THIS WEEKEND (IF
THAT IS WHAT YOU ARE LOOKING FOR) GIVEN THE STRONGER LOW-LEVEL
SOUTHWESTERLY FLOW.
THE MID-LEVEL RIDGING WILL BEGIN TO SLIDE MORE TOWARDS THE EAST ON
SATURDAY ALLOWING OUR REGION TO BE ON THE PERIPHERY OF ITS
INFLUENCE. THIS WOULD PLACE US WITHIN THE RING OF FIRE TERRITORY
WHERE ANY PIECE OF ENERGY COULD EASILY INITIATE CONVECTION. THERE
LOOKS TO BE A WEAK LEE-SIDE TROUGH THAT WILL TRY TO PUSH INTO THE
REGION ON SATURDAY FROM THE WEST-SOUTHWEST BUT THE COLUMN LOOKS
RATHER DRY, EXCEPT FOR THE SURFACE LAYER. PWATS WILL BE AROUND 1.25
INCHES, RATHER NORMAL GIVEN THE TIME OF THE YEAR. GIVEN THAT WE
SHOULD BE AMPLY UNSTABLE WITH SOME WEAK DYNAMICS FURTHER NORTH WE
ONLY HAVE A SLIGHT CHANCE ACROSS THIS REGION ON SATURDAY EVENING.
AFTER A HOT SATURDAY LOWS SATURDAY NIGHT WILL STRUGGLE TO FALL
INTO THE 60`S IN SPOTS. A FRONTAL BOUNDARY WILL MOVE INTO THE
REGION SUNDAY AND MONDAY. THIS WILL INCREASE CLOUDS SUNDAY AND
KEEP TEMPERATURES BELOW THE 90 DEGREE MARK DURING THE DAY SUNDAY.
ENOUGH INSTABILITY WILL IN PLACE DURING THE AFTERNOON FOR A FEW
STORMS TO FIRE PARTICULARLY WEST OF PHILLY CLOSER TO THE FRONT
DURING THE AFTERNOON. GOOD OVERALL GUIDANCE AGREEMENT WITH MOST WX
ELEMENTS THROUGH SUNDAY.
RAIN CHANCES INCREASE WITH THE FRONTAL PASSAGE LATE SUNDAY NIGHT AND
MONDAY. ENSEMBLES BOTH GFS AND ECMWF SHOW THE FRONTAL PASSAGE DURING
THIS TIME FRAME WITH SOME VARIABILITY IN EXACTLY WHEN THE FRONT
PASSES THROUGH. ALSO THINKING MODELING COULD BE EITHER SLIGHTLY FASTER OR
SLOWER IN FUTURE RUNS. THIS PRECLUDES LIKELY POPS FROM THE FORECAST
ATTM. SHOWERS AND THUNDERSTORMS ARE EXPECTED WITH THE FRONTAL
PASSAGE. FRONTAL TIMING WILL ALSO CONTRIBUTE TO THE AMOUNT OF
INSTABILITY AND ANY THREAT FOR STRONG STORMS OR HEAVY RAINFALL. THIS
FRONTAL BOUNDARY WILL END THE HEAT WAVE WITH MORE SEASONABLE AIR
BEHIND THE FRONT. HIGH TEMPERATURES MONDAY AND THE WIND DIRECTION
WILL ALSO BE BOTH HIGHLY DEPENDENT ON FRONTAL TIMING. FOR NOW MAINLY
BASED TIMING OF EVENTS ALONG THE LINES OF THE WPC GUIDANCE WHICH MATCH
WELL WITH THE ENSEMBLE APPROACH TAKEN WITH THIS PART OF THE
FORECAST. SKIES WILL CLEAR OUT GRADUALLY TUESDAY. HAVE GRADUALLY
DECREASED SKY COVER AND CLOUDS ON THE DAY TUESDAY ACROSS THE
REGION.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THROUGH 12Z...IFR/LIFR CONDS IN ST/FOG MUCH OF E PA AND NNJ WITH
ISOLATED SHOWERS AND CALM WIND. FOR FAR S NJ AND DE...GENERALLY
OCNL MVFR VSBY IN FOG WITH S WIND.
AFTER 12Z...ANY REMAINING IFR/LIFR FOG/STRATUS QUICKLY DISSIPATES
BY 13Z AND BECOMES VFR SCT-BKN AOA 5000 FT WITH A SW WIND G15 KT
IN THE AFTN. TWO BANDS OF TSTMS ARE MODELED BY THE SPCWRF AS DISCUSSED
IN DETAIL IN OUR NEAR TERM SECTION. HAVE FOLLOWED THIS FOR THE 06Z
TAFS WITH SUPPORT FROM THE LATEST RAPRUC. IF THESE BANDS...ESPECIALLY
THE NRN PA-NNJ BAND DEVELOP...EXPECT A BRIEF 35-40 KT GUSTY NW
OUTFLOW FROM THE STORMS.
TONIGHT...A LINE OF DYING SHOWERS AND EMBEDDED TSTMS MAY SLIDE
ESEWD FROM VCNTY KRDG-KTTN AROUND 00Z DYING OUT NEAR KPNE-KACY
AROUND 03Z. OTRW VFR WITH POSSIBLE MVFR HAZE FOG TOWARD DAWN
THURSDAY.
OUTLOOK...
THURSDAY - SATURDAY...VFR WITH SOUTHWESTERLY WINDS. POSSIBLE EARLY
MORNING HAZE MVFR VSBYS EACH MORNING.
SUNDAY...MAINLY VFR, ISOLATED THUNDERSTORMS LATE FOR PHL AND
POINTS NW. LOCALLY IFR TO MVFR IN ANY THUNDERSTORMS.
&&
.MARINE...
SEAS AND WINDS WERE FCST MUCH TOO HIGH ON THE ATLC WATERS TUE AFTN
AND 44009..WITH ITS WIND DATA PROBLEMS AND ALL..STILL BARELY JUST
MADE IT 5 FT AT 11PM EDT AND NOW AROUND 4FT. WILL DISCONTINUE THE
SCA FOR THE SNJ AND DE WATERS PROBABLY AT 6 AM IF NOT SOONER.
OTRW A GENERALLY SSW 10-20 KT FLOW PREVAILS TODAY AND TONIGHT WITH
NO HEADLINE. A BIT OF VSBY RESTRICTION IN FOG AND HAZE TIL 9 AM
EDT AND POSSIBLY IN HAZE EARLY THURSDAY MORNING. WINDS WILL PROBABLY
TURN SSE ALONG THE COASTS FOR A TIME THIS AFTN BUT EVEN THERE..THE
WSW GRADIENT FLOW MAY PREVENT MUCH OF AN EAST OF SOUTH TURN.
OUTLOOK...
SUB-ADVISORY CONDITIONS IN STORE FOR OUR WATERS THROUGH A GOOD
PORTION OF THE OUTLOOK PERIOD. WINDS WILL GENERALLY BE FROM THE
SOUTH-SOUTHWEST BY THURSDAY AS HIGH PRESSURE, OFFSHORE, WILL
DOMINATE OUR SENSIBLE WEATHER. SEAS WILL GENERALLY BE AROUND 3
FEET ACROSS ALL THE WATERS. SEAS AND WINDS WILL BEGIN TO INCREASE
THROUGHOUT THE DAY ON SUNDAY AND MONDAY AND LOOK TO REACH SCA
CRITERIA.
&&
.RIP CURRENTS...
RIP CURRENT AWARENESS WEEK JUNE 2 THROUGH 8.
PSA`S WILL AIR ON KPHI NWR AND POST DAILY AROUND 545 AM. A SHORT
AWARENESS PRESS CONFERENCE IN SURF CITY - LBI, TUE JUNE 4 2PM FOR
THOSE MEDIA REPRESENTATIVES THAT ARE INTERESTED IN RAISING RIP
CURRENT AWARENESS AND CONDITIONS FAVORING UNGUARDED LIFE THREATENING
DANGER IN THE OCEAN SURF ZONE.
MORE ON THIS IN THE AFD NEXT MONDAY JUNE 3.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT EARLY THIS MORNING FOR
ANZ453>455.
&&
$$
SYNOPSIS...DRAG/HEAVENER 0608Z
NEAR TERM...DRAG 0608Z
SHORT TERM...DRAG 0608Z
LONG TERM...GAINES/HEAVENER
AVIATION...DRAG/HEAVENER 0608Z
MARINE...DRAG/HEAVENER 0608Z
RIP CURRENTS...0608Z
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
322 AM EDT Wed May 29 2013
.NEAR TERM [Through Tonight]...
At upper levels, we see a trough over the central part of the nation
and a ridge over much of the Southeast. Surface analysis continues
to show a ridge axis extending from off the Carolina coast westward
to Louisiana. We have seen a very gradual moistening of the lower
levels over the past few days with some isolated showers over the
Gulf of Mexico and also just west of the forecast area. We believe
we will see some mainly isolated shower and thunderstorm development
this afternoon across the CWA triggered mainly be the sea breeze.
The only area with scattered PoPs will be the Suwannee Valley area
where the east-southeast synoptic flow should enhance convergence
along the sea breeze front. We have continued the recent trend of
going a degree or two above a guidance blend for max temps. Some
guidance members indicate the chance for some fog over our South
Central GA and eastern FL Big Bend zones overnight. Min temps will
be a few degrees above normal, generally ranging from the upper 60s
north to the lower 70s for the coastal zones.
&&
.SHORT TERM [Thursday Through Friday]...
Upper level ridging will continue to persist across the eastern
one-third of the CONUS through the short term period, with the
center of a 1025-1030mb surface ridge lingering to the east of the
Carolinas. This ridging will extend eastward into the north-central
Gulf of Mexico and provide at least moderate east to southeast low
level winds over the interior, with gradually increasing deep layer
moisture, with PWATs eventually climbing into the 1.50 to 1.75 inch
range by late Thursday and Friday. This will allow the Sea Breeze
Front to become a bit more convectively active over the next couple
of days, but the limited CAPE in the forecast soundings and the
fairly strong 1000-700mb Mean Layer Vector Wind (MLVW) out of the
southeast at 15 to 20 kts will keep the convection fairly weak.
Afternoon PoPs are expected to range between 20 and 30 percent
across much of the interior, with the best chances for afternoon
showers and thunderstorms over SE AL on Thursday, and SE AL and the
FL Panhandle on Friday. High temps are still expected to be quite
warm and just a bit above climo, with topping out in the mid 80s
near the coast to the lower 90s further inland, with overnight lows
moderating into the upper 60s to the lower 70s.
&&
.LONG TERM [Friday Night through Tuesday]...
A broad area of high pressure over the Southeast US and Atlantic
Ocean will remain in place from Thursday through the weekend,
resulting in easterly flow and lower than normal chances of
precipitation. The best chance at seeing isolated thunderstorms will
be in the eastern part of our CWA during this period, where the
Atlantic sea breeze may spark some convection each afternoon and
early evening as it collides with the Gulf sea breeze. Seasonable
temperatures should occur throughout the period, with highs
generally in the low 90s and lows in the mid-upper 60s. Looking
ahead to next week, a disturbance in the southern Gulf and Caribbean
is being shown by the GFS, but it is far too early to determine the
track or intensity of this possible feature.
&&
.AVIATION
[Through 06 UTC Thursday] The NARRE and HRRR guidance supports the
gridded LAMP and MOS in showing from low ceilings developing over
the eastern terminals. We show a few hours of IFR at VLD and TLH.
Visibility restrictions are not anticipated as surface winds are
forecast to remain around 4-7 kt through the night. Shower and
thunderstorm development is expected to be isolated this afternoon
and we only mention a vicinity shower at TLH and VLD.
&&
.MARINE...
More of the same is expected across our Coastal Waters, as the ridge
of high pressure to the east of the Carolinas will continue to
provide very favorable conditions for mostly nocturnal wind surges
out of the east and southeast for the next few days. These surges
will bring wind speeds into the Cautionary range and close to Small
Craft Advisory range during the late night and morning hours into
Friday, before the pressure pattern begins to weaken and break down
by the upcoming weekend.
&&
.FIRE WEATHER...
There are no concerns about red flag criteria due to sufficiently
high RH over the next several days. However, dispersion indices will
be elevated, over 75 in many areas on Thursday.
&&
.HYDROLOGY...
With only isolated to scattered showers and thunderstorms expected
over the next several days, no significant impacts are anticipated
on our area rivers.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 91 70 91 70 91 / 20 10 20 20 20
Panama City 87 72 84 73 86 / 20 10 20 20 20
Dothan 92 69 91 69 92 / 20 10 30 10 30
Albany 92 68 91 68 91 / 10 10 10 10 20
Valdosta 90 67 92 67 92 / 20 10 10 10 20
Cross City 92 67 92 68 91 / 30 10 20 10 20
Apalachicola 86 73 83 73 85 / 10 10 20 20 20
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM...Wool
SHORT TERM...Gould
LONG TERM...Godsey
AVIATION...Wool
MARINE...Gould
FIRE WEATHER...Wool
HYDROLOGY...Gould
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
259 AM EDT WED MAY 29 2013
.SHORT TERM /TODAY THROUGH THURSDAY/...
SHORT TERM REMAINS QUIET FOR THE MOST PART...WITH RIDGING ALOFT AND
MOIST SOUTHERLY SURFACE FLOW AROUND THE WESTERN PERIPHERY OF A HIGH
IN THE ATLANTIC. A WEAKNESS IN THE FLOW ALOFT OVER THE BAHAMAS HAS
LED TO AN INCREASE IN CONVECTIVE ACTIVITY...AND SOME MOISTURE FROM
THIS SYSTEM IS PROGGED TO MOVE ACROSS FLORIDA TODAY AND INTO THE
DEEP SOUTH TONIGHT. NAM AND SREF BRING SOME PRECIP TO SOUTHWEST
ZONES...BUT ECMWF AND GFS KEEP THE AREA DRY. NAM GOES GANGBUSTERS
WITH THE CAPE...WITH OVER 1500 J/KG ACROSS SOUTHERN AND WESTERN
ZONES...WHEREAS ALL OTHER GUIDANCE KEEPS CAPE VALUES BELOW ABOUT 800
J/KG. HPC DOES PAINT SOME LIGHT QPF FROM APPROXIMATELY CARROLLTON TO
CORDELE AND POINTS SOUTH AND WEST...AND LOCAL WRF AND HRRR BOTH TRY
TO DEVELOP SOME POP-UP CONVECTION THIS AFTERNOON BUT KEEP MOST OF
THE CONVECTION IN ALABAMA. FOR NOW HOWEVER AM KEEPING ANY PRECIP
WORDING OUT WITH POPS REMAINING BELOW 15 PERCENT IN THOSE AREAS BUT
TRENDS WILL HAVE TO BE MONITORED. BIGGER IMPACT WILL BE FROM THE
STRATUS THAT IS EXPECTED TO MOVE IN OVERNIGHT AND EARLY THURSDAY...
WHICH WILL KEEP TEMPS UP A LITTLE HIGHER THAN THE PAST COUPLE OF
NIGHTS. MAX TEMPS THROUGH THE SHORT TERM WILL AGAIN BE ON THE WARM
SIDE BUT ONLY A COUPLE OF DEGREES ABOVE SEASONAL NORMALS.
TDP
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
ECMWF AND GFS IN GOOD AGREEMENT INTO THE WEEKEND WITH DIFFERENCES
DEVELOPING AT THE EARLY PART OF NEXT WEEK. THE H5 RIDGE MAINTAINS
ITS HOLD OVER THE CWA THROUGH FRIDAY...THEN THE RIDGE BEGINS TO
BREAK DOWN AS THE UPPER TROUGH MOVES INTO THE MIDWEST. THIS WILL
DRIVE A COLD FRONT INTO THE TENNESSEE AND OHIO VALLEYS LATE SATURDAY
AND INTO SUNDAY AND MONDAY. THE ECMWF IS A LITTLE FASTER AND BRINGS
MOISTURE WITH THE FRONT INTO THE CWA LATE SATURDAY NIGHT. BOTH
MODELS PROG THE FRONT TO TAP INTO GULF MOISTURE SUNDAY BRINGING A
GOOD CHANCE OF PRECIP TO MUCH OF THE CWA. DIFFERENCES DEVELOP SUNDAY
NIGHT/MONDAY ON THE SPEED OF EXITING THE FRONT AND ASSOCIATED
MOISTURE. THE ECMWF PUSHES THE FRONT THROUGH BUT THE SOUTHEAST
CORNER OF THE CWA BY 12Z MONDAY WHILE THE GFS HOLDS THE FRONT BACK
CLEARING ONLY THE NORTHWEST PART OF THE CWA BY 12Z MON AND THEN
DEVELOPS A SECONDARY UPPER WAVE THAT INCREASES MOISTURE OVER MOST OF
THE CWA DURING THE DAY MONDAY. AT THIS POINT WILL MAINTAIN HIGH POPS
SUNDAY AND MONDAY AND BRING LOW OR NO POPS ON TUESDAY.
17
&&
.AVIATION...
06Z UPDATE...
VFR TO START THE PERIOD...BUT EXPECT SOME MVFR STRATUS TO MOVE IN
AROUND SUNRISE DOWN NEAR MCN. IT MAY BRIEFLY MAKE IT TO THE OTHER
TAFS SO INCLUDED THAT IN A TEMPO. OTHERWISE...VFR CIGS THROUGH THE
AFTERNOON AND EVENING WITH SE WINDS GENERALLY 5-10KT. INCREASING
MOISTURE THURSDAY MORNING SHOULD BRING MVFR TO POTENTIALLY IFR
CIGS EVERYWHERE BETWEEN 08-10Z...SO TRENDED THAT WAY IN THE ATL
TAF.
//ATL CONFIDENCE...06Z UPDATE...
LOW ON POTENTIAL FOR MVFR CIGS THIS MORNING.
MEDIUM ON TIMING OF MVFR CIGS THURSDAY MORNING.
HIGH ON ALL OTHER ELEMENTS.
TDP
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 85 64 85 66 / 5 5 5 5
ATLANTA 84 67 83 66 / 5 5 5 5
BLAIRSVILLE 81 60 81 63 / 0 5 5 5
CARTERSVILLE 85 65 84 66 / 5 5 5 5
COLUMBUS 88 69 87 69 / 5 10 10 5
GAINESVILLE 82 65 81 66 / 5 5 5 5
MACON 88 66 87 67 / 5 5 5 0
ROME 87 65 85 66 / 5 5 10 10
PEACHTREE CITY 85 65 84 66 / 5 5 5 5
VIDALIA 88 69 89 69 / 5 5 5 0
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...TDP
LONG TERM....17
AVIATION...TDP
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1154 PM CDT TUE MAY 28 2013
.DISCUSSION...
ISSUED 907 PM CDT TUE MAY 28 2013
WHILE MOST OF CENTRAL AND SOUTHEAST ILLINOIS HAS BEEN DRY THIS
EVENING...AN AREA OF VERY HEAVY RAINFALL OCCURRED ACROSS PORTIONS
OF KNOX...STARK AND MARSHALL COUNTIES. SPOTTER REPORTS AROUND 3
INCHES WERE RECEIVED ACROSS PARTS OF KNOX COUNTY. THIS RAINFALL
PRODUCED FLASH FLOODING IN SOME AREAS. THESE STORMS FORMED ALONG
AN AXIS OF HIGH INSTABILITY ON THE WARM SIDE OF A FRONT THAT
EXTENDS FROM THE CENTRAL PLAINS INTO THE GREAT LAKES.
COVERAGE AND INTENSITY OF PRECIPITATION UPSTREAM HAS BEEN ON THE
DECREASE OVERALL WITH DIMINISHING DIURNAL INSTABILITY.
HOWEVER...STILL EXPECT AT LEAST SCATTERED SHOWERS/STORMS THROUGH
THE NIGHT ACROSS THE NORTHWEST HALF OF THE FORECAST AREA. THESE
STORMS WILL BE AIDED BY AN INCREASING LOW LEVEL JET ALONG THE
SURFACE FRONT. HOWEVER...SOME OF THE HIGH RESOLUTION MODELS
SUGGEST THE CONVECTION WILL BE A LITTLE FURTHER SOUTH INTO THE
FORECAST AREA THAN IT HAS BEEN...LIKELY FIRING IN THE VICINITY OF
OUTFLOW BOUNDARIES FROM THE EARLY EVENING CONVECTION.
GOING FORECAST IS IN GOOD SHAPE OVERALL. ONLY PLAN TO TWEAK FOR
THE EXPECTED OVERNIGHT TRENDS.
BAK
&&
.AVIATION...
ISSUED 1154 PM CDT TUE MAY 28 2013
PREDOMINANTLY VFR CONDITIONS EXPECTED ACROSS THE CENTRAL ILLINOIS
TERMINALS THROUGH THE 06Z TAF VALID TIME. HOWEVER...SCATTERED
SHOWERS AND THUNDERSTORMS MAY REDUCE CIGS/VSBYS TO MVFR FOR A FEW
HOURS OVERNIGHT. SOUTHERLY WINDS SHOULD PERSIST FOR MOST OF THE
PERIOD...OUTSIDE OF ANY LOCAL STORM IMPACTS... BECOMING GUSTY
DURING PEAK DIURNAL MIXING WEDNESDAY.
BAK
&&
.PREV DISCUSSION...
ISSUED 300 PM CDT TUE MAY 28 2013
COMPLICATED WEATHER PATTERN IN GENERAL MADE MORE COMPLICATED IN
THE MODELS WITH A STRUGGLE WITH THE PATTERN SHIFT OVERALL.
HOWEVER...FOR ALL THE NUANCES WITH THE WAVES MOVING THROUGH THE
FORECAST AREA...THE ONE AGREED UPON PORTION IN ALL THE OPERATIONAL
MODELS IS THAT CENTRAL ILLINOIS WILL BE RATHER WET THROUGH THE END
OF THE WEEK. WARM FRONT WELL TO THE NORTH OF THE CWA...LEAVING ILX
IN THE WARM SECTOR WITH WARM TEMPS AND DEWPOINTS IN A RATHER MUGGY
AIRMASS. THIS WARMTH AND MOISTURE WILL HELP TO FUEL ANY MCS REMNANTS/BOUNDARIES
THAT MOVE INTO THE FA...IN ADDITION TO THE OVERALL FRONT SCHEDULED
TO MOVE INTO THE MIDWEST AT MIDWEEK. WITH SWRLY FLOW ALOFT...THE
FRONT IS GOING TO LOSE ITS FORWARD MOMENTUM...SLOW MOVING...AND
SLOW TO EXIT. AS A RESULT...ANY WAVES THAT EJECT OUT OF THE SW AND
ALONG THE BOUNDARY WILL RESULT IN ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS. HEAVY RAIN IS LIKELY INVOF WHEREVER THE FRONT
LANDS...WHICH WILL NOT ONLY BE DIFFICULT TO PIN...FRONT WILL ALSO
END UP GETTING INFLUENCED GREATLY BY MESOSCALE INFLUENCES/COLD
POOLS/OUTFLOWS AS WELL. WITH GROUND ALREADY VERY SATURATED FROM
PREVIOUS RAINS...THE FLASH FLOODING THREAT MAY GET A BREAK
TOMORROW FOR PORTIONS OF CENTRAL ILLINOIS...BUT IT WILL BE BACK BY
THURSDAY.
SHORT TERM...TONIGHT THROUGH TOMORROW...
SCATTERED THUNDERSTORMS STILL POSSIBLE THROUGH THE EVENING WITH
CONVECTIVE INITIATION LIKELY TO THE WEST IN NRN MO JUST ACROSS THE
MISS RIVER VALLEY. BOTH RUC AND NMM/WRF KEEPING SOME
ACTIVITY...THOUGH THE RUC/RAP IS ACTUALLY CONFINING MUCH OF THE
ACTIVITY TO THE NORTH. THE 4KM WRF/NMM DEVELOPS MORE OF A LINEAR
COMPLEX THAT EVENTUALLY MOVES THROUGH THE FA TO THE SE AND WEAKENS
AS IT TRAVERSES THE CWA. SHOWER THREAT FINALLY DIMINISHES BRIEFLY
FOR WEDNESDAY...THOUGH THE THREAT OF ANY INTERACTION WITH THE WARM
FRONT TO THE NORTH RESULTS IN POPS ACROSS THE NRN TIER OF THE
STATE. WARM TEMPS...SOUTHERLY WINDS...AND ABUNDANT MOISTURE IN THE
BOUNDARY LAYER WILL PUSH HEAT INDEX VALUES INTO THE UPPER 80S/NEAR
90. WINDS WILL BE RATHER BREEZY AND HELP TO COUNTER SOME OF THE
EFFECTS...THOUGH CAUTION SHOULD BE USED BY ANYONE OUTDOORS
TOMORROW.
LONG TERM...THURSDAY THROUGH MONDAY...
THE WESTERN TROF DIGS IN...AMPLIFYING THE WAVE PATTERN OVER THE
CONUS AND LEAVING THE UPPER MIDWEST IN SWRLY FLOW...THROUGH
THURSDAY...WITH WARM TEMPS YET AGAIN ON THURSDAY. TEMPS IN THE NW
SHOULD BE SOMEWHAT DAMPENED HOWEVER...BY CLOUD COVER FROM
APPROACHING BOUNDARY. IN ADDITION...DIURNAL CURVE WILL LIKELY BE
SHATTERED BY THE CONVECTIVE ACTIVITY RUINING THE STEADY CLIMB OF
TEMPERATURES IN ANY ONE SPOT AHEAD OF THAT BOUNDARY. FORECAST
CONFIDENCE ABOUT DETAILS COMPLICATED WITH THE ELONGATED TROF IN
THE ECMWF/NAM IS PROVIDING A SLIGHTLY DIFFERENT SOLUTION WITH THE
SFC SYSTEM THAN THE NAM. THAT BEING SAID...THE ECMWF IS LOOKING A
BIT MORE LIKE THE GFS IN THE 12Z RUN. THOUGH EVERYONE IS IN
AGREEMENT ABOUT ENTERING A PROLONGED PERIOD OF PRECIP THROUGH DAY
5...THE DIFFERENCES IN THE MODELS WILL IMPACT THE DYNAMICS AND
ASSOCIATED SEVERE WEATHER THREAT. FORECASTING ONSET OF THE
HEAVIEST PRECIP ALONG THE APPROACHING FRONT. IN SUMMARY...THE RAIN
IS NOT OVER AS LONG AS THAT FRONT WITH THE NEXT SYSTEM GETS SLOWED
BY PARALLEL FLOW ALOFT.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 7 AM CDT WEDNESDAY FOR ILZ027>031-
036>038-040>043-047>051.
&&
$$
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
139 AM EDT WED MAY 29 2013
.SYNOPSIS...
HIGH PRESSURE WILL BECOME ANCHORED OFF THE MID ATLANTIC COAST
OVERNIGHT THROUGH THE NEXT SEVERAL DAYS. SUMMERLIKE...GENERALLY
DRY CONDITIONS WILL PREVAIL FROM WEDNESDAY INTO THE UPCOMING
WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
THE LATEST RADAR AND SATELLITE DEPICT A LINE OF TSTMS CROSSING THE
BAY AND APPROACHING THE LOWER MD EASTERN SHORE. THIS LINE HAS THE
POTENTIAL TO INITIALLY BE STRONG AS WEAK SHORTWAVE ENERGY COMBINES
WITH MODEST INSTABILITY. HOWEVER...THE LATEST HRRR (23Z) AND SPC
MESOANALYSIS SUGGEST INSTABILITY DECLINES W-E ACROSS THE EASTERN
SHORE HENCE TSTMS ARE EXPECTED TO WEAKEN AS THEY MOVE E. AN
ISOLATED TS IS POSSIBLE ACROSS THE NORTHERN NECK AND VA EASTERN
SHORE THROUGH THE REMAINDER OF THE EVENING...BUT MOST AREAS
ELSEWHERE WILL REMAIN DRY. SKIES CLEAR OUT FROM SW TO NE AFTER
MIDNIGHT. MILD WITH LOWS MAINLY FROM THE LWR TO MID 60S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY/...
SUMMERLIKE PATTERN LOOKS TO DEVELOP. MODELS IN GOOD AGREEMENT
THAT THE 500 MB RIDGE ALOFT WILL SLOWLY BUILD ON WED AND BECOME
CENTERED ACRS SE VA AND EASTERN NC THU/FRI WITH HEIGHTS AVERAGING
588-590 DM. SFC HIGH PRESSURE WILL BE NEARLY STATIONARY WELL OFF
THE MID ATLC/SE COAST. SUMMER- LIKE CONDITIONS WILL DOMINATE WITH
HIGHS GENLY RANGING FROM THE MID 80S NEAR THE COAST TO THE UPPER
80S TO LOWER 90S INLAND (LOCALLY IN THE UPPER 70S AT THE BEACHES
OF THE EASTERN SHORE WHERE FLOW BACKS TO SSE DURING THE AFTN).
LACK OF ANY REAL TRIGGER WITH THE WARM POOL ALOFT WILL LEAD TO
WEAK LAPSE RATES ALOFT AND LITTLE CHC FOR ANY PCPN. A VERY
ISOLATED LATE AFTN/EVENING TSTM CAN`T BE RULED OUT WITH THE STRONG
SFC HEATING ...BUT COVERAGE IS EXPECTED TO BE 14% OR LESS. THE SKY
WILL AVERAGE OUT PARTLY/MOSTLY SUNNY. AIRMASS WILL NOT BE THAT
HUMID...AS OCEAN TEMPS ARE STILL QUITE COOL AND WITH AFTN
MIXING...EXPECT DEW PTS TO DROP TO THE LWR 60S DURING THE HEAT OF
THE AFTN (MID-UPR 60S IN THE MORNING HRS). SO WHILE IT WILL BE A
MARGINALLY HOT PERIOD...PEAK HEAT INDICES WILL GENLY BE ABOUT THE
SAME AS THE ACTUAL AIR TEMPERATURES. LOWS TEMPERATURES WILL
AVERAGE IN THE MID 60S...WITH UPPER 60S MORE COMMON IN THE URBAN
CENTERS.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
ABOVE NORMAL TEMPS TO CONTINUE THROUGH THE WEEKEND BEFORE A COLD
FRONT CROSSES THE REGION MONDAY INTO TUESDAY.
MUCH BETTER AGREEMENT AMONG OPERATIONAL GUIDANCE IN THE EXTENDED WRT
CNTRL CONUS TROUGH OPENING UP AND PROGRESSING EWD. MODELS CONTINUE
TO STRUGGLE WITH SEVERAL PIECES OF ENERGY DIVING DOWN THE BACKSIDE
OF THE UPPER TROUGH OVER THE PLAINS. MEAN FRONTAL POSITION SAT
MORNING EXPECTED TO BE IN THE VICINITY OF THE GREAT
LAKES...STRETCHING SWWD INTO SRN NM. WAVY UPPER LEVEL PATTERN
EXPECTED TO PRODUCE SEVERAL WAVES ALONG THE SFC FRONT AS IT SLOWLY
PROGRESSES EWD. WHILE LATEST GFS AND EURE DERIVE UPPER LEVEL ENERGY
FROM DIFFERENT SOURCES...MEDIUM RANGE MODELS IN GOOD AGREEMENT WITH
EJECTING A SHORTWAVE EWD FROM THE LOWER MO RIVER VALLEY SUN
AFTERNOON. SHORTWAVE THEN FORECAST TO PHASE WITH UPPER TROUGH AS IT
TRAVERSES THE ERN STATES...REACHING THE LOCAL AREA MONDAY AFTERNOON.
MEANWHILE...UPPER/SFC HIGH PRESSURE WILL BE PUSHED FARTHER OFFSHORE
AS THE TROUGH APPROACHES. THE RESULT WILL BE DEEP SWLY FLOW AND
MOISTURE ADVECTION OVER THE MID ATLANTIC. DEEP MOISTURE EXPECTED AS
PRECIP WATER VALUES APPROACH 2 INCHES (+2 STD DEV) MON AFTERNOON.
PREVIOUSLY MENTIONED WEAKNESS UNDERCUTTING THE RIDGE EXPECTED TO
REMAIN WELL OFFSHORE. MODELS IN FAIR AGREEMENT (GFS ~ 6 HOURS
SLOWER) WITH TIMING OF THE FRONT MON AFTERNOON THROUGH MON NIGHT.
WHILE ITS STILL DAY 7...POTENTIAL FOR ONE OR MORE FRONTAL WAVES AND
DEEP MOISTURE COULD PRODUCE LOCALLY HEAVY RAINFALL ACROSS THE REGION
(WHICH IS NOT UNCHARACTERISTIC FOR THIS TIME OF YEAR). THETA-E
ADVECTION AND TEMPS IN THE LOW/MID 80S WILL MAINTAIN A MARGINALLY
UNSTABLE AIRMASS FOR THUNDERSTORM ACTIVITY. EXTENDED RANGE MODELS
SUGGEST BLOCKING OVER THE NRN ATLANTIC MAY CAUSE THE TROUGH TO HANG
UP ALONG THE COAST WITH SHOWERS POSSIBLY CONTINUING INTO TUES.
WARM/UNSTABLE AIRMASS WITH STEEP LOW LEVEL LAPSE RATES WILL PROVIDE
FOR AFTERNOON CU SAT-SUN. HOWEVER...NEAR SEASONABLE PRECIP
WATERS...COOL OCEAN TEMPS (DEWPOINTS IN THE LOW/MID 60S) AND A LACK
OF UPPER LEVEL SUPPORT (WEAK FLOW) WILL LIMIT AFTERNOON
CONVECTION...EVEN WITH THE PRESENCE OF A WEAK LEE SIDE TROUGH. THUS
HAVE CAPPED AFTERNOON POPS AT 10-14 PCT AND OVERNIGHT POPS AT 10
PCT. DAYTIME TEMPS +1 STD DEV FORECAST THROUGH SUNDAY. SLIGHTLY
COOLER MONDAY (LOW/MID 80S) AND TUESDAY (UPPER 70S/LOW 80S).
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS ACROSS AREA TERMINALS THIS MORNING...WITH SIMILAR
CONDITIONS EXPECTED THROUGHOUT THE UPCOMING TAF PERIOD. HIGH
PRESSURE WL BECOME ANCHORED JUST OFFSHORE FOR THE LATTER HALF OF
THE WEKEK. EXPECT S-SW WINDS TO INCREASE BY MIDDAY AS DIURNAL
MIXING RESUMES, WITH WINDS QUICKLY DIMINISHING AFTER SUNSET.
APART FROM SOME SCT CU (MAINLY ACROSS COASTAL TERMINALS), EXPECT
MAINLY CLR CONDS AND DRY WX THROUGH EARLY THURSDAY.
OUTLOOK: HIGH PRESSURE REMAINS DOMINATE WX FEATURE ACROSS THE
REGION. ONLY REAL POTENTIAL CIG/VSBY RESTRICTION THE NEXT FEW DAYS
COMING IN PATCHY LOW STRATUS/SHALLOW GROUND FOG (MIFG). OTW, DRY
WX LOOKS TO PERSIST AT LEAST LATE SUNDAY OR MONDAY AHEAD OF AN
APPROACHING COLD FRONT.
&&
.MARINE...
WARM FRONT HAS LIFTED OVER THE WATER THIS AFTERNOON WITH S/SW WINDS
AOB 15 KT IN THE BAY AND AOB 20 KT COASTAL WATERS POST FRONTAL.
GRADIENT BETWEEN STRONG LOW PRESSURE OVER THE MIDWEST AND HIGH
PRESSURE OVER THE WRN ATLANTIC WILL RESULT IN INCREASING WINDS ALOFT
OVER THE WATERS. WAA AND A STRONG LOW LEVEL INVERSION WILL INHIBIT
THESE HIGHER VELOCITY WINDS FROM REACHING THE WATER. HOWEVER...WINDS
OVER THE BAY MAY STILL GUST OVER 15 KT AT TIMES THROUGH
TONIGHT...ESPECIALLY WITH SLY CHANNELING. WAVEWATCH GUIDANCE BRINGS
IN 5 FT SEAS 20 NM OUT TONIGHT...BUT LOOKS LIKE IT MAY BE OVERDONE.
NO SCA HEADLINES ANTICIPATED ATTM TONIGHT. THEREAFTER...AN EXTENDED
PERIOD OF HIGH PRESSURE/FAIR WEATHER (SUB SCA CONDITIONS) EXPECTED
THROUGH THE UPCOMING WEEKEND. S/SW WINDS AOB 15 KT. WAVES 1 TO 2 FT
AND SEAS 2 TO 4 FT.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LKB
NEAR TERM...AJZ/LKB
SHORT TERM...LKB
LONG TERM...SAM
AVIATION...MAM
MARINE...SAM
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
411 AM CDT WED MAY 29 2013
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 400 AM CDT WED MAY 29 2013
A VERY VOLATILE WATER VAPOR IMAGE AND H5 PATTERN IS IN PLACE THIS
MORNING AS A NEGATIVELY TILTED TROUGH SITS FROM NEAR YELLOW STONE
SOUTHEAST TO THE BIG BEND REGION OF TEXAS. CONVECTION ACROSS THE
PLAINS YESTERDAY AND OVERNIGHT HAS LEFT MULTIPLE SHORT WAVES/MCVS
LITTERED ACROSS NATIONS MIDSECTION. DURING THE DAY...THE MAIN TROUGH
WILL MIGRATE E/NE ACROSS THE PLAINS...AND BY THE END OF THE PERIOD
THE TROUGH WILL STRETCH FROM A DEVELOPING CLOSED LOW OVER THE BLACK
HILLS SOUTHEAST TOWARD NE TEXAS.
AT 330 AM...THE WARM WAS JUST PASSING THROUGH FORT DODGE IN IOWA AND
HAS ACTUALLY BEGUN TO PICK UP SOME MOMENTUM TOWARD THE NORTH IN THE
LAST FEW HOURS. BASED ON THE RAP...THIS BOUNDARY WILL BE NEAR I-90
AT 15Z...BY 18Z IT SHOULD BE WORKING ITS WAY THROUGH THE TWIN CITIES
BEFORE BECOMING STATIONARY AT 00Z FROM A SFC LOW OVER NORTH CENTRAL
NEB...NORTHEAST THROUGH ABERDEEN AND UP TOWARD LAKE OF THE WOODS.
FOR THIS FORECAST...FAVORED A NAM/ECMWF BLEND FOR HANDLING OF LARGE
SCALE FEATURES SUCH AS SHORTWAVES AND THE LLJ...WHILE A BLEND OF THE
HI-RES CAMS WERE USED TO TRY AND ADD DETAIL TO THE POP FORECAST.
BASED ON THAT...WHAT FOLLOWS IS THE CURRENT THINKING IS OF 330 AM
FOR WHAT WILL HAPPEN TODAY.
FOR THE WARM FRONT COMING NORTH...IS LOOKING LIKE CONVECTIVE
ACTIVITY WILL BE SCATTERED IN NATURE...AS H85 LLJ IS ACTUALLY
SOMEWHAT DIFFLUENT OVER MN...WITH ONE BRANCH SPLITTING OF FROM IOWA
INTO SODAK...WITH THE REST OF THE JET FANNING OUT TOWARD THE NE
ACROSS MN INTO WI. THE HRRR AND OTHER CAMS ALONG WITH THE RAP IS
SHOWING A BATCH OF ELEVATED SHOWERS AND STORMS DEVELOPING EARLY THIS
MORNING NORTH OF THE BOUNDARY AND HEADING TOWARD SE MN BY THE EARLY
AFTERNOON. THIS SEEMS TO BE IN RESPONSE TO A SHORTWAVE NOTED ON
WATER VAPOR CURRENTLY WEST OF OMAHA THAT THE RAP DRAGS NE TOWARD SE
MN THROUGH THE MORNING. THE HRRR IS BY FAR THE MOST AGGRESSIVE WITH
THIS CONVECTION AT THE MOMENT...BUT OUTSIDE OF SOME POTENTIAL FOR
HAIL...THE SEVERE THREAT LOOKS LIMITED WITH THIS BATCH OF
CONVECTION...IF IT DOES FORM.
FOR THE SEVERE THREAT...ATTENTION REALLY TURNS TO ERN SODAK/WRN MN
THIS AFTERNOON. WITH THE NAM/ECMWF SHOWING THE LLJ ANGLING BACK NW
INTO SODAK IN RESPONSE TO HEIGHT FALLS ALOFT...THIS SHOULD LEAD TO
THE INITIATION OF MORE SURFACE BASED CONVECTION SOMEWHERE NEAR THE
RETREATING WARM FRONT IN ERN SODAK/WRN MN. FORECAST SOUNDINGS FROM
THE RAP/NAM SHOW ATMO REMAINING CAPPED ACROSS WRN MN UNTIL ABOUT
21Z...AT WHICH POINT YOU ARE DEALING WITH AROUND 1500 J/KG OF SBCAPE
IN A WEAKLY CAPPED...STRONGLY SHEARED /ESPECIALLY IN THE LOWEST 3
KM/ ENVIRONMENT. NMM/ARW BASED CAMS SHOW LITTLE CONVECTION
DEVELOPING THROUGH 21Z...BUT QUICKLY GENERATE CONVECTION AFTER
21Z...SO WAITED TO INTRODUCE ANY LIKELY POPS UNTIL 21Z. SEEING TWO
CAMPS IN THE CAMS FOR HOW CONVECTION DEVELOPS THIS AFTERNOON...WITH
THE ARW AND NSSL-WRF GENERATING STORMS OVER WRN MN...WHILE THE NMM
AND SPCWRF GENERATE CONVECTION OVER ERN SODAK. THIS IDEA FOR
ACTIVITY STARTING OUT WEST THIS AFTERNOON IS FURTHER SUPPORTED BY
THE SPC SSEO...WHICH SHOWS NEIGHBORHOOD PROBABILITIES FOR UPDRAFT
HELICITY AND UPDRAFT STRENGTH BEING MAXIMIZED OVER ERN SODAK INTO
WRN MN...WITH VERY LITTLE ACTIVITY BEING NOTED FROM SRN INTO ERN MN
AND WRN WI THIS AFTERNOON. GIVEN DEGREE OF LOW LEVEL SHEAR...THERE
WILL BE THE THREAT FOR TORNADIC ACTIVITY WHILE THE STORMS AREA
DISCRETE...BUT DO EXPECT STORMS THIS AFTERNOON TO GROW
UPSCALE...WITH A HAIL/WIND THREAT CONTINUING INTO THE NIGHT.
FOR TONIGHT...WHAT HAPPENS WITH CONVECTION THIS AFTERNOON WILL PLAY
A LARGE ROLE IN WHAT HAPPENS TONIGHT. WITHIN THE CAMS...WE ARE AGAIN
LOOKING AT TWO CAMPS. THE NMM AND SPCWRF DO NOT BRING THE DAKOTA
CONVECTION INTO MN...WHILE SENDING ANOTHER MCS RACING ACROSS
IOWA...KEEPING MUCH OF THE MPX CWA DRY. THE ARW AND NSSL-WRF CONGEAL
THE AFTERNOON CELLS IN THE WEST INTO A LINE...AND TRACK THAT COMPLEX
OF STORMS EAST ACROSS THE STATE THROUGH THE NIGHT. GIVEN EXPECTED
EVOLUTION OF THE LLJ FROM THE ECMWF/NAM...FAVOR THE ARW/NSSL-WRF
CAMP...WITH A COMPLEX OF STORMS WORKING EAST ACROSS THE AREA THROUGH
THE NIGHT...WITH CONVECTIVE COVERAGE AND INTENSITY SLOWLY
DIMINISHING AFTER 6Z.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 400 AM CDT WED MAY 29 2013
CUTOFF UPPER CIRCULATION DEVELOPS AND LINGERS ACROSS THE HIGH
PLAINS AND WESTERN GREAT LAKES INTO THE COMING WEEKEND. AS THE
UPPER LOW TAKES FORM OVER THE NORTHERN PLAINS THROUGH THURSDAY...
A BELT OF FASTER WESTERLY FLOW ASSOCIATED WITH A SHORT WAVE
TROUGH WILL MOVE EAST FROM THE CENTRAL PLAINS TO THE MIDWEST.
CLOUDS WILL REMAIN ABUNDANT OVER THE REGION...AND WILL LIMIT
SIGNIFICANT DESTABILIZATION. HOWEVER...LARGE SCALE ASCENT FROM
THE INCOMING SHORT WAVE AND STEEPENING MID LEVEL LAPSE WILL LIKELY
SUPPORT SOME STRONG TO SEVERE STORMS ACROSS CENTRAL AND SOUTHERN
MINNESOTA THURSDAY AFTERNOON AND THURSDAY NIGHT. THE SURFACE LOW
WILL DEEPEN AND OCCLUDE IN EASTERN NORTH DAKOTA INTO THURSDAY
NIGHT...AND WILL HELP PUSH THE COLD FRONT EAST INTO CENTRAL
MINNESOTA. WE SHOULD SEE HIGH POPS INTO THURSDAY AFTERNOON AS
THIS SYSTEM MOVES THROUGH...AND MAINLY OVER EASTERN AREAS INTO
THURSDAY NIGHT AHEAD OF COLD FRONT. HAIL AND STRONG WINDS WILL BE
THE MAIN THREATS...ALONG WITH HEAVY RAIN. WILL TRAIL POPS OFF TO
THE WEST DURING THE AFTERNOON. THE 00Z ECMWF IS MOST CONSISTENT
WITH DRIVING A DRY SLOT NORTHEAST OVER THE AREA INTO
FRIDAY...LIMITING SIGNIFICANT CONVECTION FURTHER EAST IN THE
REMNANT WARM SECTOR INTO WESTERN WISCONSIN. THIS WILL LIMIT SEVERE
WEATHER DEVELOPMENT ON FRIDAY...WITH THE DAY 3 OUTLOOK MAINLY
SOUTHEAST OF OUR CWA.
SYSTEM SLOW TO MOVE THROUGH THE AREA...WITH COLD AIR CIRCULATING
OVER THE REGION WELL INTO THE WEEKEND. EXPECTING DRIER CONDITIONS
DEVELOPING SATURDAY NIGHT AND LINGERING INTO MONDAY. TEMPERATURES
WILL RANGE SOME 5 TO 10 DEGREES BELOW AVERAGE THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1050 PM CDT TUE MAY 28 2013
CONDS EXPECTED TO DROP TO IFR ARND MIDNIGHT AND REMAIN THERE THRU
THE EARLY MORNING HOURS. MAY BE SOME BREAKS IN THE OVC IN WRN
MN...ALLOWING CONDS TO JUMP FROM MVFR TO VFR THEN BACK DOWN TO IFR
AS PATCHY FOG AND/OR LOW STRATUS DEVELOPS. HAVE SEEN WRN MN BREAK
OUT INTO CLR SKIES...BUT HIGH CONVECTIVE DEBRIS CLOUDS STARTING TO
MOVE IN FROM THE S AND W WHICH COULD PLAY HAVOC WITH THE
CIGS...ESP FOR WRN SITES INCLUDING KRWF-KAXN-KSTC. SITES OUTSIDE
OF KMSP ARE LIKELY TO SEE VSBYS DROP TO ARND 1SM...IF NOT
LOWER...ESPECIALLY IN SPOTS WHERE HIGH CLOUDS DO NOT MOVE IN AND
IN THE FAVORED FOG SITES...INCLUDING KRNH-KEAU. CONDS GRADUALLY
IMPROVE AFTER DAYBREAK AND A FEW HOURS OF VFR CONDS ARE EXPECTED.
CONVECTION THEN DEVELOPS LATE TMRW AFTN INTO TMRW EVE AS A WMFNT
LIFTS N THROUGH THE REGION. PREVAILING THINKING IS THAT INITIAL
ONSET OF PRECIP WOULD BE TSTMS THEN WOULD BE FOLLOWED BY -RA. HAVE
PLAYED THE TSRA AS TEMPO GROUPS ATTM...WITH ONLY DEGRADING CONDS
DOWN TO MVFR DUE TO UNCERTAINTY BUT HVY RAIN COULD EASILY DROP
VSBYS TO LESS THAN 3SM. WINDS TO REMAIN LGT/VRBL THRU MUCH OF THE
OVERNIGHT HOURS THEN PICK UP FROM THE SE TMRW... INCLUDING BECOMING
GUSTY IN THE AFTN THRU THE EARLY EVE.
KMSP...STARTED OUT WITH CONDS IN MINIMAL MVFR RANGE. ALTHOUGH
SATELLITE TRENDS INDICATE A CLEARING-OUT AREA OVER WRN MN...NOT
TOO SURE THIS WILL MAKE IT TO KMSP BEFORE HIGH CONVECTIVE DEBRIS
MOVES IN ATOP THE LOW CEILINGS...NOT ALLOWING A VFR PERIOD IN THE
EARLY MRNG HOURS. AS WINDS SETTLE DOWN...A COMBINATION OF FOG AND
LOW STRATUS WILL DEGRADE VSBYS INTO MVFR RANGE. AM NOT LOOKING
FOR VSBY LESS THAN 3SM BUT IT CANNOT BE RULED OUT ENTIRELY. AFTER
DAYBREAK...LOW STRATUS ERODES AND A PERIOD OF VFR IS EXPECTED.
MIDLVL CEILINGS DEVELOP BY MID- AFTN AHEAD OF A WMFNT EXPECTED TO
LIFT N. WITH THIS FNT...SCATTERED CONVECTION WILL DEVELOP. UNCLEAR
AS TO IF IT WILL DIRECTLY MOVE OVER MSP SO HAVE RAN WITH A TEMPO
GROUP IN THE LATE AFTN TO EARLY EVE FOR CB/TS FOR ONLY MVFR CONDS.
THAT SAID...IFR OR LOWER CONDS ARE CERTAINLY POSSIBLE. MORE STEADY
RAIN IS THEN EXPECTED BEHIND THE INITIAL TSTMS WITH UPPER-RANGE
MVFR CONDS...ALTHOUGH A PERIOD OF OCNL TSRA AFTER 00Z LOOKS TO
OCCUR.
/OUTLOOK FOR KMSP/
THU...MVFR OR LOWER CIGS LIKELY. SHRA/TSRA LIKELY. WINDS S 15-20
KTS.
FRI...MVFR OR LOWER CIGS LIKELY. SHRA/TSRA LIKELY. WINDS SW 10-15
KTS.
SAT...MVFR CIGS POSSIBLE. CHANCE SHRA/TSRA. WINDS WNW 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...DWE
AVIATION...JPC
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
359 PM CDT MON MAY 27 2013
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 400 PM CDT MON MAY 27 2013
PERSISTENT AREA OF LIGHT SHOWERS AND DRIZZLE NOTED SOUTH OF A LINE
FROM KMSP TO KEAU AND EAST OF LINE FROM SHAKOPEE TO TRUMAN. THIS
REGION IS REMNANTS OF MCS WHICH FORMED OVER NORTHERN IOWA DURING
THE OVERNIGHT. AREA CORRELATES WELL WITH GFS40 THETA E ADVECTION.
CURRENT HRRR ALSO SEEMS TO HAVE A GOOD HANDLE OF AREAL COVERAGE
AND INTENSITY. REGION WAS STRUGGLING EARLIER THIS AFTERNOON AS IT
MARCHED NORTH INTO DRIER AIR COLUMN AND CONVERGENCE DEPICTED AT
250MB. EXPECT CONTINUED SLOW MIGRATION OF PRECIPITATION SHIELD
NORTH AS LATE DAY SURFACE HEATING CONTINUES TO MAINTAIN OR SLOWLY
ENHANCE CURRENT INTENSITY. LOOK FOR CESSATION OF MOST PRECIP. FROM
THIS FEATURE BY AROUND 28/06Z. FOR THE REMAINDER OF THE OVERNIGHT
EXPECT ANOTHER LATE NIGHT MCS TO FOLLOW THE PLACEMENT OF A WARM
FRONTAL BOUNDARY ABOVE CENTRAL TO NORTHERN IOWA. MCS WILL AGAIN
FORM OVER EASTERN SODAK AND FOLLOW 1000-500MB THICKNESS LINE
DROPPING ANOTHER THREE QUARTERS TO ONE INCH OF RAINFALL OVER PORTIONS
OF CENTRAL TO NORTHERN IOWA. SHOULD BE ANOTHER RATHER GLANCING
BLOW FOR THE FAR SW AND SOUTH CENTRAL PORTION OF THE MN CWA...SIMILAR
TO THE PREVIOUS THREE NIGHTS...WITH A FEW TENTHS TO POSSIBLY FOUR
TENTHS OF AN INCH EXPECTED OVER THIS REGION...WITH HEAVIEST AMOUNTS
OVER FAR SOUTH CENTRAL MINNESOTA.
MCS OVER NORTHERN IOWA SHOULD FOLLOW SAME TRAJECTORY AS TODAY`S
PCPN SHIELD...WITH POSSIBLY A FEW MORE EMBEDDED THUNDERSTORMS
AS LI`S GRADUALLY RECEDE INTO NEGATIVE TERRITORY. MOISTURE FROM
THIS SYSTEM WILL AGAIN BE ON THE WEAK SIDE...WITH MAINLY AROUND
ONE TENTH OF AN INCH ON AVERAGE ANTICIPATED PRIOR TO PASSAGE.
USED A BLEND BETWEEN NAM AND GFS40 FOR TUESDAY`S HIGH TEMPERATURES
...AND THEN THROTTLED BACK ONE CATEGORY. OF COURSE INTENSITY AND
FORWARD SPEED OF RAINFALL SHIELD MENTIONED ABOVE WILL DETERMINE
WHETHER TEMPERATURES NEED TO BE CUT EVEN FURTHER.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 400 PM CDT MON MAY 27 2013
TUESDAY EVENING INTO WEDNESDAY MORNING IS EXPECTED TO BE A DRY TIME
FRAME...AS THE SURFACE WARM FRONT REMAINS TO THE SOUTH OVER SOUTHERN
IOWA AND THE LOW LEVEL MOISTURE/WARM AIR ADVECTION IS FOCUSED THERE
AS WELL. HOWEVER...SHOWERS AND THUNDERSTORMS SHOULD OVERSPREAD THE
AREA DURING THE DAY ON WEDNESDAY...AS THE WESTERN TROUGH SURGES
EASTWARD...AND THE FRONT AND ADVECTION PROCESSES SHIFT NORTHWARD IN
CONJUNCTION WITH A SHORTWAVE IMPULSE. STRONGLY DIFFLUENT FLOW ALOFT
COMBINES WITH THE LOW LEVEL JET INFLUENCES...AND COULD SET THE STAGE
FOR A FEW SEVERE STORMS ON WEDNESDAY AFTERNOON/EVE.
ON THURSDAY...THE UPPER TROUGH TAKES ON A NEGATIVE TILT...AS THE
WARM FRONT LIFTS ACROSS THE AREA. THIS WILL CONTINUE THE SEVERE
WEATHER THREAT AND ENHANCE THE FLOODING POTENTIAL AS WELL. PWATS
WILL REMAIN NEAR CLIMATOLOGICAL RECORD VALUES /1.5 TO 2.0
INCHES/...WHILE THE TROUGH STRUCTURE PROVIDES THE SHEAR SUFFICIENT
FOR STRONG POSSIBLY SEVERE STORMS. ON FRIDAY...THE COLD FRONTAL
BOUNDARY ASSOCIATED WITH THE SURFACE LOW PASSES ACROSS THE
AREA...AND CONTINUES THE THREAT FOR WIDESPREAD SHOWERS AND
THUNDERSTORMS.
ALTHOUGH THE THREAT FOR SEVERE STORMS WILL DIMINISH ON SATURDAY IN
THE WAKE OF THE SURFACE LOW...RAIN SHOWERS WILL CONTINUE TO BE
POSSIBLE OVER THE WEEKEND AS THE MID/UPPER TROUGH ROTATES OVER THE
UPPER MIDWEST.
HIGH TEMPERATURES WILL REMAIN NEAR TO SLIGHTLY ABOVE NORMAL FOR THE
END OF MAY...RANGING THROUGH THE MID TO UPPER 70S...AND THEN DECLINE
TO AROUND 5 TO 10 DEGREES BELOW NORMAL FOR THE FIRST FEW DAYS IN
JUNE /65 TO 70 DEGREES/.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 118 PM CDT MON MAY 27 2013
A LITTLE COMPLEX THIS AFTERNOON WITH REMNANTS OF SHOWER AND ISOLATED
THUNDERSTORM COMPLEX NOTED ON 0.5 DEGREE REFLECTIVIT OVER SE CWA.
AREA HAS SLOWLY BEEN ERODING IN BOTH AREA AND INTENSITY AS IT HAS
PROGRESSED NORTH FROM SOUTH CENTRAL MN. HRRR HAS PEGGED DEPRECIATION
IN REFLECTIVITY TRENDS QUITE WELL. IF THIS PANS OUT SYSTEM WILL
AFFECT PORTIONS OF EAST CENTRAL MN AND FAR SOUTHERN WEST CENTRAL
WISCONSIN THROUGH 00Z TIME FRAME...THEN DISSIPATE OR TREK NE OUT
OF AIRPORT REGION. MVFR CIGS CURRENTLY IN PLACE OVER ALL TAF
SITES...WITH AREA OF LOW MVFR TO POCKETS OF IFR CIGS NOTED OVER
SW MN. LOOK FOR SLOW LOWERING OF CLOUD DECK AFT 00Z MOST SITES
...WITH EASTERLY FLOW CONTINUINING INTO END OF PERIOD. LOOK FOR
IFR CIGS BY 09Z MOST LOCALES...WITH LIFR CIGS ALSO A POSSIBILITY.
FORCING AS DEPICTED ON EUROPEAN MODEL WILL PORTEND ANOTHER ROUND
OF SHOWERS AND ISOLATED THUNDERSTORMS DEVELOPING OVER SW MN AND
WEST CENTRAL WI BY 12Z...AND REMAINDER OF REGION BETWEEN 14 AND
18Z TIME FRAME. CIGS WILL RISE BACK TO MVFR CONDITIONS MOST LOCALES
ASSOCIATED WITH SAME.
KMSP...
IR SATELLITE INDICATED SMALL AREA OF VFR CIGS JUST TO SW OF
AIRPORT AT 18Z. EXPECT THIS TO FILL IN LATER THIS AFTN BACK TO
MVFR CONDITIONS. ALTHOUGH NORTHERN TREKKING MCS REMNANTS
CONTINUE TO SLOWLY DEGRADE OVER THE WESTERN PORTION...STILL
EXPECT SHORT PERIOD OF LIGHT DRIZZLE/-RW EARLY PORTION OF PERIOD.
ONCE COMPLEX MARCHES THROUGH REMAINDER OF LATE AFTN/EVEN HOURS
WILL BY DRY...WITH CIGS LOWERING BEHIND COMPLEX. SE FLOW THROUGH
PERIOD...WITH GOOD FORCING PROGNOSTICATING ANOTHER ROUND OF LIGHT
SHOWERS FROM 14Z THROUGH AT LEAST 18Z. THIS SECOND ROUND MAY LAST
INTO 20Z ON TUESDAY. TOMORROW EVEN WILL REMAIN DRY...WITH MVFR
CONTINUIING.
/OUTLOOK FOR KMSP/
TUE...CHC MVFR OR LOWER CIGS. CHC SHRA/TSRA. WINDS S 5-10 KTS.
WED...CHC MVFR OR LOWER CIGS. CHC SHRA/TSRA. WINDS S 10-15 KTS.
THU...CHC MVFR OR LOWER CIGS. CHC SHRA/TSRA. WINDS S 15-20 KTS.
FRI...CHC MVFR OR LOWER CIGS. CHC SHRA/TSRA. WINDS SW-W 15-20KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...AJZ
LONG TERM...LS
AVIATION...AJZ
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
150 PM CDT MON MAY 27 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 413 AM CDT MON MAY 27 2013...UPDATED FOR 18Z TAF.
THUNDERSTORMS WITH EXCESSIVE RAINFALL ARE ONCE AGAIN JUST SOUTH OF
OUR MN CWA EARLY THIS MORNING. THE ACTIVITY IS FOCUSED JUST NORTH OF
A STATIONARY FRONT THAT MEANDERS ACROSS NE/IA AND AT THE NOSE OF THE
LOW LEVEL MOISTURE TRANSPORT. CONVERSATION WITH THE SATELLITE
PRECIPITATION ESTIMATE GROUP INDICATED THAT AROUND A FOOT OF RAIN
HAS LIKELY FALLEN IN THE LAST 24 HOURS OVER PARTS OF NW IA. AS I
MENTIONED YESTERDAY...THE 850MB DEW POINT ON THE KOMA RAOB SATURDAY
EVENING WAS 15 DEG C. THEIR 850MB DEW POINT SUNDAY EVENING HAD RISEN
TO 17 DEG C.
THE COMPLEX OF STORMS OVER NW IA HAS TAKEN ON A CIRCULATION THIS
MORNING WITH A BOW RACING SOUTHEAST ACROSS WESTERN IA. SHORT TERM
WRF SOLUTIONS SHOW AN AREA OF SHOWERS AND PERHAPS AN ISOLATED
THUNDERSTORM PASSING SLOWLY EASTWARD ACROSS SOUTHERN MN THIS MORNING
WITH SOME SHOWERS REACHING INTO WEST CENTRAL WI THIS AFTERNOON. WE
HAVE BEEN OVER FORECASTING PRECIP THE PAST FEW DAYS AS A DRY
EASTERLY FLOW HAS PREVAILED...SIMILAR TO WHAT THE ECMWF INDICATED
FOR MUCH OF THE WEEKEND A FEW DAYS BACK. HENCE...WILL KEEP POPS
HIGHEST IN THE FAR SOUTH WITH DRY WEATHER IN THE NORTHERN CWA. RAIN
AMOUNTS THIS MORNING MAY REACH A HALF TO ONE INCH ALONG THE I-90
CORRIDOR WITH A SIGNIFICANT DROP TO THE NORTH.
TONIGHT IS A FORECAST PROBLEM ON RAINFALL ACROSS THE SOUTHERN AND
EASTERN CWA. THERE ARE TWO CAMPS. THE DETERMINISTIC RUNS WOULD DRIVE
SHOWERS AND THUNDERSTORMS NORTHEAST ACROSS OUR AREA AS A STRONG
SHORT WAVE LIFTS NORTHEAST FROM THE CENTRAL PLAINS. ON THE
OTHER HAND... THE VARIOUS WRF SOLUTIONS HAVE HARDLY ANYTHING AT ALL
FOR US WITH ANOTHER LONG NIGHT OF STORMINESS ACROSS NE...IA AND
NORTHERN IL. WHAT WE CAN SEE IS THAT THE STATIONARY FRONT ON THE
NAM/GFS AND THE VARIOUS WRF/S IS ACTUALLY PROGGED TO DROP A LITTLE
SOUTH TODAY BEFORE RETURNING BACK TO ITS POSITION BY TUESDAY
MORNING. IN ADDITION...THE LOW LEVEL MOISTURE TRANSPORT WHICH HAS
BEEN ORIENTATED SOUTH TO NORTH INTO EASTERN NE/WESTERN IA IS PROGGED
TO VEER DURING THE NIGHT WITH THE NOSE OF THE TRANSPORT INTO
SOUTHERN IA AND NORTHERN IL LATE IN THE NIGHT. THE POOL OF 15-17 DEG
850 MB DEW POINTS OVER NE IS ALSO FORECAST TO BREAK DOWN TONIGHT
WITH 12 DEG C DEW POINT FLOWING OUR WAY. THE ONE SOLUTION THAT DOES
NOT GO ALONG WITH THIS IS THE ECMWF. IT WOULD NOT ONLY BRING A SHORT
WAVE THROUGH... BUT ALSO THE LOW LEVEL MOISTURE TRANSPORT PUSHES
ACROSS SOUTHERN MN ALONG WITH 850 MB DEW POINTS OF 14 DEG C.
THEREFORE...THE DAY SHIFT MAY NEED TO ISSUE A FLASH FLOOD WATCH FOR
TONIGHT AND TUESDAY MORNING IF THE NAM/GFS AND THE WRF/S START
TRENDING TOWARDS THE ECMWF. OUR 3 HOURLY FFG VALUES ACROSS SOUTHERN
MN ARE IN THE 1.5 TO 2 INCH RANGE. SO...RAIN AMOUNTS ALONG THE I-90
CORRIDOR WILL NEED TO BE WATCHED THIS MORNING WITH MORE RAIN
INCOMING TONIGHT. WE HAVE SEEN OVER THE PAST FEW NIGHTS THE RAIN
AMOUNTS JUST TO OUR SOUTH AND WEST REACHING NEARLY 2 INCHES IN AN
HOUR... AND THIS WENT ON FOR SEVERAL HOURS.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 413 AM CDT MON MAY 27 2013
FOR THE LONG TERM...WEDNESDAY THROUGH FRIDAY STILL LOOK WET...WITH
CHANCES FOR SEVERE WEATHER IN THERE AS WELL. THE 27.00 MEDIUM RANGE
MODEL RUNS HAVE CONTINUED THE TREND OF THEIR 26.12 RUNS OF THE
FRONT FOR MID-LATE WEEK MOVING THROUGH A BIT FASTER. AS A
RESULT...THE POTENTIAL FOR SEVERE WEATHER THAT WAS LOOKING GOOD
FOR THURSDAY AND FRIDAY LAST NIGHT IS NOW LOOKING MORE LIKE
WEDNESDAY AND THURSDAY.
THIS PERIOD LOOKS TO HAVE THE POTENTIAL TO START OFF WET TUESDAY
MORNING AS THE WARM FRONT IS FINALLY LIFTING NORTH THROUGH THE
AREA. MOST AGGRESSIVE MODEL WITH PRECIP GOING INTO TUESDAY MORNING
IS THE ECMWF. REST OF THE DETERMINISTIC MODELS...ALONG WITH HI-RES
CAMS SHOW MAIN H85 MOISTURE TRANSPORT FROM TONIGHT INTO TUESDAY
MORNING LAYING ACROSS IA INTO SRN WI. THE ECMWF HAS A MUCH
STRONGER H85 AND SFC WAVE LIFTING NORTH ACROSS MN DURING THIS
PERIOD...WHICH HELPS DIRECT A GOOD CHUNK OF THE MOISTURE TRANSPORT
UP ACROSS MN INTO WRN WI. HAVE LIKELY POPS GOING ACROSS ERN MN/WRN
WI TUESDAY MORNING...THOUGH GIVEN HOW MODELS HAVE PERFORMED THE
PAST COUPLE OF NIGHTS WITH BEING A LITTLE EAGER IN BRINGING PRECIP
NORTH...CONFIDENCE STILL A BIT SHAKY AS TO HOW THE MORNING WILL
PLAY OUT. GOOD NEWS ABOUT TUESDAY THOUGH...ALL MODELS SHOW A
DRYING TREND FOR THE AFTERNOON INTO TUESDAY NIGHT...WITH A DRY
PERIOD LOOKING POSSIBLE FOR MUCH OF THE AREA THEN. THERE IS EVEN
THE POTENTIAL TO SEE SOME HIGHS IN THE 80S OUT WEST IF THE NAM/GFS
CLEARING WERE TO MATERIALIZE OUT THERE.
TUESDAY NIGHT...A NEGATIVELY TILTED H5 WAVE WILL START WORKING OUT
ACROSS THE SRN PLAINS...WITH H85 WINDS BACKING CONSIDERABLY
THROUGH THE NIGHT...WITH ALL GUIDANCE SHOWING ANOTHER 40-50 KT LLJ
COMING OUT OF THE PLAINS AND COMING UP INTO ERN NEB/CENTRAL IOWA
BY WEDNESDAY MORNING. AS RESULT...STARTED TO INCREASE POPS AFTER
6Z WED MORNING TO ACCOUNT FOR THE INCREASED WAA/MOISTURE TRANSPORT
STARTING TO TAKE AIM AT SRN MN...THOUGH THAT MAY BE TOO AGGRESSIVE
WITH BRINGING PRECIP BACK.
FOR WEDNESDAY...THE NAM/GFS/ECMWF ALL SHOW A 40+ KT LLJ WORKING UP
INTO MN...WHICH WILL HELP SET THE STAGE FOR MORE WIDESPREAD
THUNDERSTORM ACTIVITY...ALONG WITH THE THREAT FOR SEVERE
WEATHER...AS INDICATED BY THE SLIGHT RISK ACROSS MOST OF THE MPX
CWA IN THE DAY 3 SPC OUTLOOK. IN ADDITION...DRYING TREND NOTED ON
TUESDAY IS ACTUALLY A WEAK COLD FRONT THAT WILL DROP INTO IOWA
TUESDAY NIGHT...BUT SURGE NORTH ACROSS MN/WI ON WEDNESDAY. SHEAR
PROFILES SHOW MOST OF THE SHEAR BEING OF THE SPEED
VARIETY...THOUGH NAM PROFILES...ESPECIALLY IN WRN MN DO SHOW SOME
LOW LEVEL TURNING OF THE WINDS. IN ADDITION TO THE MAINLY SPEED
SHEAR...SHEAR VECTORS ARE MAINLY LINED UP PARALLEL TO THE LOW
LEVEL FORCING FEATURES...WHICH STILL POINTS TO MAINLY LINEAR
CONVECTIVE MODES FOR WEDNESDAY INTO WEDNESDAY NIGHT.
FOR WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...MODELS SHOW SFC
FEATURES AND STRONG LLJ JUST GRADUALLY SHIFTING EAST...WITH THE
MPX CWA SITTING SQUARE UNDERNEATH THE LLJ DURING THIS PERIOD. THIS
SHOULD RESULT IN AT LEAST A COUPLE ROUNDS OF THUNDERSTORMS MOVING
ACROSS THE AREA. IN ADDITION...SEVERE WEATHER STILL LOOKS LIKE A
GOOD POSSIBILITY FOR THURSDAY AS WELL...WITH SIMILAR LARGE SCALE
FEATURES FORECAST FOR THURSDAY AS IS CURRENTLY BEING INDICATED FOR
WEDNESDAY. SEVERE THREAT THOUGH FOR THURSDAY WILL BE TIED CLOSELY
TO HOW POTENTIALLY WIDESPREAD CONVECTION WEDNESDAY INTO WEDNESDAY
NIGHT MODIFIES INSTABILITY PROFILES FOR THURSDAY. AT ANY
RATE...THE LARGE SCALE FORCING THURSDAY STILL POINTS TO THE
POTENTIAL FOR ANOTHER DAY OF SEVERE WEATHER. IN ADDITION...PWATS
WILL BE INCREASING TO BETWEEN 160 AND 200 PERCENT OF NORMAL /NOT
TOO FAR FROM THE MAY PWAT RECORD FOR MPX OF 1.68 INCHES/ AHEAD OF
THE COLD FRONT WEDNESDAY AND THURSDAY...WHICH MEANS A CLOSE EYE
WILL NEED TO BE KEPT ON THE HYDRO ASPECT OF THINGS AS WELL.
FOR FRIDAY...MEDIUM RANGE MODELS SHOW FRONT WORKING THROUGH
MN...WITH MAIN H85 MOISTURE TRANSPORT SITUATED EAST OF THE MPX
CWA. THIS WILL PUSH THE HEAVY RAIN THREAT EAST OF THE AREA ON
FRIDAY. HOWEVER...UPPER LOW ON FRIDAY WILL ALSO BE WORKING ACROSS
THE DAKOTAS INTO MN...WHICH WILL LEAD STEEPENING LAPSE RATES.
THIS SHOULD LEAD TO ONE MORE ROUND OF THUNDERSTORMS ALONG THE COLD
FRONT ON FRIDAY...WITH A THREAT FOR SEVERE WEATHER
CONTINUING...THOUGH SHEAR DOES NOT LOOK AS GOOD ON FRIDAY AS THE
LOW LEVEL AND MID LEVEL JETS SHIFT EAST OF THE MPX AREA.
FRIDAY NIGHT INTO SATURDAY...THE COLD FRONT LOOKS TO FINALLY PULL
CLEAR OF THE MPX AREA. HOWEVER...THE COLD TROUGH ALOFT WILL BE
OVERHEAD...WHICH WILL LEAD TO THE THREAT FOR DIURNALLY DRIVEN
INSTABILITY SHOWERS SATURDAY BENEATH THE COLD AIR ALOFT. SATURDAY
NIGHT...COOL/DRY CANADIAN HIGH PRESSURE LOOKS TO FINALLY START
MOVING INTO THE AREA...WHICH WILL FINALLY START TO DRY THINGS
OUT...THOUGH WILL RESULT IN A COOL START TO THE MONTH OF JUNE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 118 PM CDT MON MAY 27 2013
A LITTLE COMPLEX THIS AFTERNOON WITH REMNANTS OF SHOWER AND ISOLATED
THUNDERSTORM COMPLEX NOTED ON 0.5 DEGREE REFLECTIVIT OVER SE CWA.
AREA HAS SLOWLY BEEN ERODING IN BOTH AREA AND INTENSITY AS IT HAS
PROGRESSED NORTH FROM SOUTH CENTRAL MN. HRRR HAS PEGGED DEPRECIATION
IN REFLECTIVITY TRENDS QUITE WELL. IF THIS PANS OUT SYSTEM WILL
AFFECT PORTIONS OF EAST CENTRAL MN AND FAR SOUTHERN WEST CENTRAL
WISCONSIN THROUGH 00Z TIME FRAME...THEN DISSIPATE OR TREK NE OUT
OF AIRPORT REGION. MVFR CIGS CURRENTLY IN PLACE OVER ALL TAF
SITES...WITH AREA OF LOW MVFR TO POCKETS OF IFR CIGS NOTED OVER
SW MN. LOOK FOR SLOW LOWERING OF CLOUD DECK AFT 00Z MOST SITES
...WITH EASTERLY FLOW CONTINUINING INTO END OF PERIOD. LOOK FOR
IFR CIGS BY 09Z MOST LOCALES...WITH LIFR CIGS ALSO A POSSIBILITY.
FORCING AS DEPICTED ON EUROPEAN MODEL WILL PORTEND ANOTHER ROUND
OF SHOWERS AND ISOLATED THUNDERSTORMS DEVELOPING OVER SW MN AND
WEST CENTRAL WI BY 12Z...AND REMAINDER OF REGION BETWEEN 14 AND
18Z TIME FRAME. CIGS WILL RISE BACK TO MVFR CONDITIONS MOST LOCALES
ASSOCIATED WITH SAME.
KMSP...
IR SATELLITE INDICATED SMALL AREA OF VFR CIGS JUST TO SW OF
AIRPORT AT 18Z. EXPECT THIS TO FILL IN LATER THIS AFTN BACK TO
MVFR CONDITIONS. ALTHOUGH NORTHERN TREKKING MCS REMNANTS
CONTINUE TO SLOWLY DEGRADE OVER THE WESTERN PORTION...STILL
EXPECT SHORT PERIOD OF LIGHT DRIZZLE/-RW EARLY PORTION OF PERIOD.
ONCE COMPLEX MARCHES THROUGH REMAINDER OF LATE AFTN/EVEN HOURS
WILL BY DRY...WITH CIGS LOWERING BEHIND COMPLEX. SE FLOW THROUGH
PERIOD...WITH GOOD FORCING PROGNOSTICATING ANOTHER ROUND OF LIGHT
SHOWERS FROM 14Z THROUGH AT LEAST 18Z. THIS SECOND ROUND MAY LAST
INTO 20Z ON TUESDAY. TOMORROW EVEN WILL REMAIN DRY...WITH MVFR
CONTINUIING.
/OUTLOOK FOR KMSP/
TUE...CHC MVFR OR LOWER CIGS. CHC SHRA/TSRA. WINDS S 5-10 KTS.
WED...CHC MVFR OR LOWER CIGS. CHC SHRA/TSRA. WINDS S 10-15 KTS.
THU...CHC MVFR OR LOWER CIGS. CHC SHRA/TSRA. WINDS S 15-20 KTS.
FRI...CHC MVFR OR LOWER CIGS. CHC SHRA/TSRA. WINDS SW-W 15-20KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...RAH
LONG TERM...MPG
AVIATION...AJZ
AREA FORECAST DISCUSSION
NWS HASTINGS NE
407 AM CDT WED MAY 29 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 406 AM CDT WED MAY 29 2013
MAIN FORECAST CONCERN WILL BE
CHANCES FOR THUNDERSTORMS.
RADAR FROM KLNX SHOWS THAT MANY OF THE THUNDERSTORMS TO THE WEST
HAVE DIMINISHED BUT A RAIN SHIELD REMAINS. THERE ARE A COUPLE OF
BOUNDARIES THAT ARE SHOWING UP ON KUEX RADAR...ONE FROM THE
CONVECTION TO THE WEST AND ANOTHER FROM CONVECTION TO THE SOUTH.
WHEN THESE COLLIDE APPEARS TO BE THE BEST CHANCE FOR SOME SHOWERS
AND THUNDERSTORMS EARLY THIS MORNING. THERE HAVE BEEN A FEW THAT
GOT STARTED BUT SOON WANED.
MODELS ARE SIMILAR WITH THE UPPER LEVEL LOW THAT MOVES FROM THE
NORTHERN ROCKIES INTO THE NORTHERN HIGH PLAINS TODAY AND TONIGHT.
THERE IS A SURFACE LOW ON THE HIGH PLAINS THAT TRIES TO MOVE
EAST...BUT DOES NOT MAKE IT THROUGH THE AREA. THE SURFACE PRESSURE
GRADIENT TIGHTENS THIS MORNING AHEAD OF THE SURFACE LOW. WINDS
WILL START TO INCREASE. THE STRONGEST WINDS WILL BE IN THE
SOUTHERN PART OF THE FORECAST AREA...BUT BREEZY CONDITIONS ARE
EXPECTED ACROSS THE AREA TODAY. WILL KEEP THE WIND ADVISORY AS IS
FOR NOW.
THE NEXT CONCERN WILL BE WHEN THUNDERSTORMS WILL DEVELOP. THE
UPPER LEVEL WAVE WILL START TO AFFECT THE AREA THIS MORNING AND
SOME THUNDERSTORM DEVELOPMENT IS NOT OUT OF THE QUESTION. THE NAM
AND THE GFS SHOW A DEFINITIVE INCREASE IN QPF DURING THE MORNING
BUT THE RAP AND 4KM WRF BOTH HOLD OFF UNTIL LATER. WILL KEEP SOME
LOW POPS IN FOR THE MORNING...BUT RAMP IT UP LATER THIS MORNING
AND EARLY THIS AFTERNOON WHEN THE UPPER WAVE IS MOVING INTO THE
AREA. SEVERE WEATHER IS EXPECTED DURING THE AFTERNOON AND EVENING
WHEN MUCAPES ARE EXPECTED TO BE OVER 3500 J/KG. THE SEVERE WEATHER
WILL LIKELY CONTINUE INTO THE EVENING BUT THE SEVERE THREAT WILL
DIMINISH LATER TONIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 406 AM CDT WED MAY 29 2013
MAIN STORY: A REPRIEVE FROM THE THREAT OF TSTMS WILL OCCUR AS
TEMPS TUMBLE TO BELOW NORMAL THIS WEEKEND...THEN THE THREAT
RETURNS EARLY NEXT WEEK AS SUMMER WARMTH RETURNS.
ALOFT: THE TROF CURRENTLY MOVING THRU THE W WILL CLOSE OFF OVER
THE NRN PLAINS THU NGT-FRI BEFORE OPENING UP AND SLOWLY MIGRATING
INTO THE GREAT LAKES AND MIDWEST THIS WEEKEND. A MODEST SHRTWV
RIDGE WILL ADVANCE INTO THE PLAINS SUN-MON...AS THE NEXT TROF
MOVES INTO THE PAC NW. ALL THE WHILE THE WESTERLIES WILL GRADUALLY
LIFT BACK INTO THE NRN USA.
SFC: A COOL FRONT WILL MOVE THRU LATE THU AFTN/EVE. HOWEVER...THE
TAIL END OF THE FRONT MAY NOT ENTIRELY CLEAR THE SE FRINGE OF OUR
FCST AREA UNTIL FRI EVNG. THIS FRONT WILL BE FOLLOWED BY A SECONDARY
STRONGER COLD FRONT FRI EVNG. HIGH PRES DRIFTS THRU SUN WITH RETURN
FLOW INTENSIFYING WITH ITS DEPARTURE TO THE E AND REDEVELOPMENT OF
THE LEE TROF...AS LOW PRES HEADS E ALONG THE USA-CAN BORDER. HEAT
BUILDS OVER THE REGION MON-TUE UNTIL THE NEXT COOL FRONT MOVES THRU
TUE NGT OR WED. COOL HIGH PRES THEN BUILDS IN THU.
HAZARDS: FIRE WX MAY BECOME A CONCERN THU/FRI BETWEEN 2PM-8PM.
ATTM DO NOT ENVISION A RFW BUT FIRE DANGER COULD BE ELEVATED.
THERE ARE MULTIPLE CHANCES FOR TSTMS THU-FRI BUT COVERAGE AND
INTENSITY WILL BE LOW DUE TO DIMINISHING MSTR/INSTABILITY. SOME
SVR TSTMS WILL BE POSSIBLE EARLY NEXT WEEK AS INSTABILITY
INCREASES.
THE DAILY DETAILS...
THU: THE BACKSIDE OF AN MCS MAY STILL LINGER SE OF THE TRI-CITIES
IN THE MRNG. OTHERWISE DECREASING CLOUDS.
THE DRYLINE WILL PRESS INTO THE FCST AREA IN THE WARM SECTOR OF A
992 MB SFC LOW OVER THE DAKOTAS...WITH ITS ASSOCIATED COOL FRONT
DROPPING INTO THE NW FRINGE LATE. THE LFQ OF THE 80 KT ULJ WILL BE
OVER THE CNTRL PLAINS...BUT HIGH QUALITY MSTR WILL BE RAPIDLY ON THE
DECREASE. AN ISOLATED SHWR/TSTM IS POSSIBLE...MAINLY E OF HWY 281.
FIRE DANGER: WE NEED TO WATCH ALONG AND W OF HWY 183. USED LOWER
NAM 2M DWPTS WHICH DROPS INTO THE UPR 30S. WINDS LOOK MARGINAL.
FRI: WEAK HIGH PRES BUILDS IN BEFORE SECONDARY COLD FRONTAL
PASSAGE. A BREEZY DAY W OF HWY 281. THERE IS A VERY LOW
PROBABILITY FOR AN ISOLATED SHWR/TSTM IN VICINITY OF THE
APPROACHING FRONT AND THE STALLED FRONT OVER THE SE. FIRE DANGER
COULD BE ELEVATED AGAIN W OF HWY 183.
SAT: BREEZY AND COOL WITH HIGH TEMPS ABOUT 10F COOLER THAN
NORMAL. COULD SEE A FEW SPRINKLES N OF I-80 IN THE AFTN.
SUN: NICE AND COMFORTABLE. A GOOD DAY TO OPEN UP THE HOUSE.
SUN NGT: A STRONG PULSE OF WAA/MSTR TRANSPORT AS 40 KT LLJ
DEVELOPS. MSTR WILL INITIALLY BE LACKING SO IT APPEARS THIS
PROCESS WILL NOT DESTABILIZE THE ATMS. JUST TOO SOON SO THE FCST
IS DRY.
MON-TUE: RISK OF TSTMS INCREASES AND PROBABLY PEAKS TUE. WE ARE
PROBABLY TOO LOW ON OUR TEMPS BY 3-5F. WOULD NOT BE SURPRISED TO SEE
MID 90S SW OF THE TRI-CITIES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1223 AM CDT WED MAY 29 2013
THUNDERSTORMS TO THE WEST WILL EVENTUALLY MOVE INTO THE KGRI
TERMINAL AREA. WITH THE THUNDERSTORMS THERE ARE SOME LOWER
CEILINGS AND VISIBILITIES AS WELL. THE LOWER CLOUDS WILL LINGER
ACROSS THE AREA THROUGH MUCH OF THE DAY. THE AFTERNOON AND EVENING
WILL BRING ANOTHER CHANCE FOR SOME THUNDERSTORMS. THE FIRST
ROUND SHOULD BE DURING THE AFTERNOON WITH A SMALL BREAK POSSIBLE
FOR A WHILE. MORE THUNDERSTORMS WILL LIKELY MOVE INTO THE KGRI
TERMINAL AREA AT THE VERY END OF THE PERIOD. THERE ARE CHANCES FOR
SOME THUNDERSTORMS THROUGH MUCH IF NOT ALL OF THE PERIOD AND TRIED
TO PICK THE MOST LIKELY TIMING.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...WIND ADVISORY FROM 10 AM THIS MORNING TO 9 PM CDT THIS EVENING
FOR KSZ006-007-017>019.
&&
$$
SHORT TERM...JCB
LONG TERM...HALBLAUB
AVIATION...JCB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1205 AM CDT WED MAY 29 2013
.AVIATION...
06Z TAFS FOR KOFK...KOMA AND KLNK.
LATEST 88D MOSAIC LOOP WAS SHOWING LINE OF TSRA EXTENDING FROMS-CNTRL
SD THRU THE NEB PANHANDLE. EXPECT COMPLEX WILL BEGIN FALLING APART
OVER THE NEXT SEVERAL HOURS AS IT MOVES EAST. OTHERWISE...INFLUX
OF LLVL MOISTURE WILL CONTINUE THRU THE REST OF TONIGHT RESULT IN
CONDITIONS DETERIORATING FROM VFR TO IFR OVER ERN NEB THRU THE
MORNING HOURS. MVFR/IFR CIGS WILL LIKELY PREVAIL AT ALL TAF SITES
THEN UNTIL LATE WED MORNING. BY WED AFTN...EXPECT THE NEXT ROUND
OF TSRA ACTIVITY ACROSS ERN NEB. THUS HAVE OPTED TO INCLUDE PROB30
GROUPS FROM LATE AFTN TO LATE EVENING.
DEE
PREV DISCUSSION... /ISSUED 249 PM CDT TUE MAY 28 2013/
DISCUSSION...
CONVECTION/POSSIBLE FLOODING THROUGH THURSDAY REMAINS PRIMARY
CONCERN.
SUBJECTIVELY PLACED QUASI-STATIONARY FRONT EXTENDED FROM FAR SERN
NEBR INTO SWRN IA AT 19Z WITH CU FIELD THICKENING NEAR/SOUTH OF
IT...ALTHOUGH VIEW SOMEWHAT HINDERED BY HIGHER CLOUDS. ALTHOUGH
FIRST AREA OF CONVECTION WAS DEVELOPING SE OF THE REGION...AND
LEADS SOME SMALL DOUBTS TO WHAT MAY HAPPEN FARTHER NW...VARIOUS
MODEL QPF INCLUDING RAP/HRRR AND 4KM WRF DVLP PRECIP OVER SERN
ZONES THROUGH EARLY EVENING. THIS LOOKS REASONABLE GIVE LATEST SPC
RUC MESO ANALYSIS PAGE SHOWED SRN ZONES ON EDGE OF ML CAPE AXIS OF
3000-4000 J/KG WITH WEAKENED/NO CAP. LOW LEVEL/DEEPER SHEAR
FAVORABLE FOR SEVERE WEATHER...SEE LATEST WATCH/MCD FOR INFO ON
THIS. SINCE SRN ZONES RECEIVED 1-2+ INCHES OF RAIN LAST EVENING...
RIVERS/STREAMS ARE RUNNING HIGH OR CLOSE TO FLOODING IN SOME
CASES. WITH FFG VALUES UNDER 2 INCHES...OPTED TO ISSUE A FLASH
FLOOD WATCH SERN COUNTIES THROUGH TONIGHT. EXTENDED WATCH TO NEBR
CITY/4 SW IA COUNTIES IN CASE STRENGTHENING LOW LEVEL JET ALLOWS
ACTIVITY TO SPREAD/DEVELOP N LATER THIS EVENING...BUT IT WAS NOTED
THAT 4KM WRF AND HRRR DROPPED CONVECTION SE THRU EARLY EVENING.
OTHERWISE ADJUSTED POPS NRN ZONES TONIGHT TO REFLECT BETTER
CHANCES LATER TONIGHT AS LOW LEVEL JET STRENGTHENS N ACROSS THE
AREA CLOSER TO AND AFTER 06Z.
DIURNALLY DECREASED POPS THRU MIDDAY WEDNESDAY BEFORE STRONGER
UPPER TROUGH BEGINS CRASHING UPPER HGTS INTO CNTRL NEBR. THIS
COULD ALLOW A LITTLE EARLIER CONVECTIVE DEVELOPMENT...IF IT EVEN
DECREASES...AND COULD ALSO SET THE STAGE FOR A SEVERE WEATHER AND
HEAVY RAIN THREAT OVER A LARGER PART OF THE FORECAST AREA. WITH
TRAINING POSSIBLE AS UPPER FLOW BECOMES MORE PARALLEL TO MEAN
SHEAR VECTORS THRU WED EVENING...TRAINING OF ECHOES COULD ADD TO
FLOODING POTENTIAL. THIS MAY NECESSITATE A FLASH FLOOD WATCH OVER
A LARGER PART OF THE AREA FOR LATE WED/WED NIGHT IN LATER
FORECASTS...BUT FOR NOW FIRST FLASH FLOOD WATCH WILL ADDRESS
SHORTER TERM FLOODING THREAT.
ACTIVE WEATHER COULD PERSIST INTO THURSDAY AS JET WRAPS ACROSS
SRN ZONES ON SOUTH END OF CLOSING UPPER LOW. QUESTION WILL THEN
SHIFT TO AMOUNT OF RESIDUAL MOISTURE THAT WILL REMAIN OVER AREA AS
UPPER TEMPS COOL BUT SURFACE WINDS TAKE ON A MORE WRLY...
DOWNSLOPE...COMPONENT. FOR NOW MADE LITTLE/NO CHANGES TO PREVIOUS
FORECAST POPS...WHICH WERE FAIRLY HIGH YET THROUGH THU
EVENING...BUT LOWERED LATE THU NGT. NO CHANGES MADE TO MODEST POPS
FRIDAY OR REST OF MODEL/PRIOR FORECAST BLEND REST OF FORECAST.
SOME POTENTIAL FOR TEMPERATURES TO REALLY WARM TOMORROW AS SRLY
WINDS INCREASE AHEAD OF TROUGH AND WITH WRLY COMPONENT TO SURFACE
WINDS ON THURSDAY. HOWEVER...WITH RISK/UNCERTAINTY OF RESIDUAL
CLOUDS AND OR TSTMS...OPTED FOR LITTLE CHANGE FROM PREVIOUS
FORECAST WHICH WAS FAIRLY ALIGNED WITH GUIDANCE.
CHERMOK
HYDROLOGY...UPDATED AT 110 PM CDT...
FOR INFO ON FLASH FLOOD WATCH SEE ABOVE. OTHERWISE FLOOD WARNING
CONTINUES FOR TURKEY CREEK AT WILBER. THOUGH IT HAS CRESTED AND
STARTED FALLING FOR NOW...IT IS FORECAST TO RISE AGAIN LATER
TONIGHT AND WEDNESDAY. THE LITTLE AND BIG NEMAHA RIVERS IN
SOUTHEAST NEBRASKA DID RISE TO JUST BELOW FLOOD STAGE BUT HAVE
SINCE STARTED TO DECLINE. WARNINGS ALSO CONTINUE FOR THE MISSOURI
RIVER FROM PLATTSMOUTH DOWNSTREAM TO RULO FOR SIGNIFICANT RISES
OVER THE NEXT FEW DAYS. OMAHA ON THE MISSOURI RIVER IS FORECAST TO
RISE...BUT REMAIN JUST BELOW FLOOD LEVELS BUT WILL EVENTUALLY NEED
A FLOOD ADVISORY. THE NISHNABOTNA RIVER BASIN DID ALSO SEE
SIGNIFICANT IN BANK RISES...BUT REMAINED BELOW FLOOD STAGE AND
HAVE STARTED TO FALL. A FLOOD WARNING WAS ISSUED ON THE LITTLE
SIOUX RIVER NEAR TURIN AS IT IS FORECAST TO GO ABOUT TWO FEET
ABOVE FLOOD STAGE BY FRIDAY.
MEYER
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1233 AM CDT WED MAY 29 2013
.UPDATE...
SEE UPDATED AVIATION DISCUSSION BELOW.
NO MAJOR CHANGES TO THE GOING FORECAST THIS EVENING. THUNDERSTORMS
ARE CURRENTLY MOVING OVER THE BLACK HILLS AND WILL CONTINUE TO
PROGRESS NORTHEAST THIS EVENING. POPS AND WX MAY BE AN HOUR OR TWO
FAST BUT APPEAR TO BE IN DECENT SHAPE BASED ON CURRENT RADAR TRENDS.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT
THE MODELS ARE IN GOOD AGREEMENT THROUGH THE SHORT TERM WITH THE
MAIN WEATHER FEATURES. A LARGE NEGATIVELY TILTED UPPER LEVEL LOW
PRESSURE TROUGH OVER THE SOUTHWEST US STILL SET TO KICK OUT INTO
THE NORTHERN PLAINS WEDNESDAY THROUGH THURSDAY AND CLOSING OFF
ACROSS OUR REGION. FOR TONIGHT...AN INITIAL WAVE WILL EJECT OUT
TONIGHT INTO OUR REGION BRINGING AN MCS ACROSS MAINLY THE SOUTHERN
CWA THIS EVENING AND OVERNIGHT. THE HRRR AND WRF MODELS BOTH SHOW
AN MCS MOVING ACROSS SOUTHERN SD TONIGHT. FOR MUCH OF THE EASTERN
CWA...IT WILL BE DRY THROUGH MUCH OF THE NIGHT. WITH CLEARING
SKIES AND WINDS BECOMING LIGHT TONIGHT...EXPECT SOME MORE FOG TO
FORM FROM THE JAMES VALLEY AND EAST TONIGHT AND REMAIN INTO
WEDNESDAY MORNING. THE MODELS ALSO SHOW A GOOD LLJ ALONG WITH GOOD
LOW AND MID LEVEL WAA DEVELOPING THROUGH THE NIGHT AND WEDNESDAY
MORNING. THIS WILL AID IN NUMEROUS SHOWER AND THUNDERSTORM
DEVELOPMENT LATER TONIGHT AND WEDNESDAY. BROAD SCALE UPPER LEVEL
DIVERGENCE WITH THE UPPER TROUGH WILL CONTINUE TO PROVIDE GOOD
ASCENT INTO WEDNESDAY NIGHT AND THURSDAY MORNING ACROSS THE CWA.
THE MODELS ALL SHOW A GOOD SURFACE LOW PRESSURE AREA IN EASTERN
COLORADO LIFTING NORTHEAST INTO NORTH DAKOTA WEDNESDAY AFTERNOON
INTO THURSDAY EVENING AND DEEPENING.
EVERYTHING IS SET FOR SOME SEVERE WEATHER POSSIBILITIES AND HEAVY
RAIN DEVELOPMENT WEDNESDAY AND WEDNESDAY NIGHT. THE THING THAT MAY
HOLD OFF MORE WIDESPREAD SEVERE WEATHER DEVELOPMENT WILL BE EARLY
SHOWER AND THUNDERSTORM DEVELOPMENT ACROSS THE CWA AND CLOUD COVER
THROUGH THE DAY AND EVENING WEDNESDAY. THIS WILL HOLD BACK THE
DEVELOPMENT OF HIGH INSTABILITY. NONETHELESS...DEEP LAYER
SHEAR...MOISTURE AND INSTABILITY WILL BE THERE FOR SOME SEVERE
STORMS ALONG WITH HEAVY RAINFALL. MADE SOME CALLS IN THE HEAVY
RAIN AREAS TODAY AND IT SEEMS MOST OF THE RAINFALL OVER THE LAST
SEVERAL DAYS HAD SOAKED IN PRETTY GOOD. HAVE INCREASED CHANCES OF
RAINFALL ACROSS THE REGION THROUGH WEDNESDAY NIGHT ALONG WITH
ADDING IN THE MENTION OF HEAVY RAIN AND SEVERE WEATHER
POSSIBILITIES. MUCH OF THE RAINFALL MAY END THURSDAY MORNING IN
THE EASTERN CWA AS THE DRY LINE/COLD FRONT SWINGS IN QUICKLY
THROUGH THE DAY BEHIND THE SURFACE LOW PRESSURE AREA. IN FACT...IT
MAY BECOME WINDY ACROSS THE CWA THURSDAY AFTERNOON AND EVENING
WITH A STRONG SURFACE LOW PRESSURE AREA TO THE NORTH ALONG WITH
GOOD MIXING. LOWERED POPS FOR THURSDAY NIGHT ACROSS THE CWA.
.LONG TERM...FRIDAY THROUGH TUESDAY
THE PERIOD BEGINS WITH A LARGE UPPER LEVEL LOW PRESSURE SYSTEM
SITUATED OVER THE NORTHERN PLAINS. THIS SYSTEM WILL BRING PERIODS
OF SHOWERS AND PERHAPS A THUNDERSTORM OR TWO DURING THE AFTERNOON
HOURS ON FRIDAY. CAPE VALUES ARE REDUCED SIGNIFICANTLY BY FRIDAY
NIGHT SO WILL ONLY MENTION SHOWERS THROUGH THE WEEKEND. DEPENDING
ON THE PLACEMENT OF THE LOW PRESSURE...HIGH TEMPERATURES ON
SATURDAY COULD BE PRETTY CHILLY. THE 12Z RUN OF THE ECMWF IS
SUGGESTING 925MB TEMPERATURES WILL ONLY WARM INTO THE MID/UPPER
SINGLE DIGITS. THANKFULLY THE GFS/GEM DEPICT SLIGHTLY WARMER LOW
LEVEL TEMPERATURES. OVERALL SATURDAY WILL BE CHILLY WITH HIGHS
ONLY IN THE UPPER 50S...TO THE MID 60S EXPECTED. SUNDAY WILL MARK
THE BEGINNING OF A WARMING TREND WITH TEMPERATURES FINALLY
REACHING ABOVE NORMAL BY MONDAY.
CHANCES FOR THUNDERSTORMS WILL RETURN TO THE FORECAST BY MONDAY
NIGHT. A SURFACE LOW PRESSURE AND COLD FRONT SLIDING ACROSS THE
REGION WILL BE THE FOCUS MECHANISM FOR CONVECTION.
&&
.AVIATION...
06Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
PRIMARILY VFR CONDITIONS ARE EXPECTED THROUGH MOST OF THE NIGHT.
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE BETWEEN 06Z AND 07Z FOR
KPIR. ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS WILL DEVELOP AND
SPREAD OVER THE AREA WEDNESDAY MORNING AND AFTERNOON. MVFR CIGS
WILL BEGIN TO AFFECT THE TAF SITES WITH THESE STORMS. VSBY MAY ALSO
FALL TO MVFR/IFR IN HEAVIER CONVECTION ON WEDNESDAY.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...DORN
SHORT TERM...MOHR
LONG TERM...SD
AVIATION...DORN
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
1239 AM CDT WED MAY 29 2013
.DISCUSSION...PLEASE SEE THE AVIATION DISCUSSION BELOW FOR MORE
DETAILS.
&&
.AVIATION...WIDESPREAD MVFR CEILINGS WL PERSIST THROUGH 14-17Z
ACROSS SOUTH TX. BEYOND THAT TIME-FRAME...CEILINGS WL RISE JUST ABV
MVFR LVLS TO 3500-4500 FT. THE PRESSURE AND THERMAL GRADIENTS WL
REMAIN TIGHT THROUGH THE PD. THIS WL RESULT IN WIND GUSTS UP TO
30-35 KT IN THE AFTN ACROSS MUCH OF THE AREA. MEXICAN CONVECTION
WEST OF EAGLE PASS IS EXPECTED TO WEAKEN THROUGH THE MORNING HOURS
BUT MAY GIVE A BRIEF OF PCPN FOR LRD DURING THE 11-13Z TIME-FRAME.
THIS CONVECTION IS ASSOCIATED WITH A S/WV EMBEDDED IN AN
APPROACHING TROUGH AXIS. AS THESE FEATURES PUSH THROUGH THE AREA
TDA...THERE WL BE THE POSSIBILITY OF AT LEAST ISOLATED
CONVECTION...ESPECIALLY THE NRN AREAS. MVFR CEILINGS WL REDEVELOP
IN THE 23Z-03Z TIME-FRAME GIVEN THE STRONG MOISTURE TRANSPORT IN
THE BOUNDARY LAYER.
&&
.PREV DISCUSSION... /ISSUED 920 PM CDT TUE MAY 28 2013/
DISCUSSION...DID NOT MESS WITH MINIMUM TEMPERATURES...BUT DID
ADJUST DEW POINTS AND HOURLY TEMPERATURES BASED ON CURRENT OBS AND
TRENDS. ALSO...DID KEEP 20 POPS FOR THE EXTREME NORTHWEST...AS 4
KM HRRR MODEL IS SHOWING ACTIVITY CREEPING TOWARD AREA ALBEIT
WEAKER. LAPS ANALYSIS IS SHOWING INCREASING CAP/CIN DEVELOPING OUT
WEST...BUT GOOD SOUTHEAST WINDS AT SURFACE AND NEAR SURFACE MAY
ALLOW SOME OF THIS ACTIVITY TO CREEP INTO THE AREA AFTER MIDNIGHT.
INCREASED WINDS JUST A BIT OVER INLAND AREAS AS WELL. REST OF
FORECAST IS FINE FOR NOW.
MARINE...DECIDED TO EXTEND THE SCA FOR THE BAYS TIL 4 AM...WHICH
MAY BE A TAD LONG BUT BELIEVE SUSTAINED WINDS WILL CONTINUE TO BE
NEAR SCA AND GUST WILL GENERALLY EXCEED THOSE VALUES SINCE UPPER
LOW WILL LIKELY DEEPEN SURFACE PRESSURE WHICH WILL KEEP GRADIENT
TIGHT ENOUGH. KEPT SCA FOR GULFMEX AS-IS FOR NOW...BUT WILL LIKELY
NEED TO BE EXTENDED BY MID SHIFT FOR AT LEAST WINDS.
PREV DISCUSSION... /ISSUED 647 PM CDT TUE MAY 28 2013/
DISCUSSION...UPDATED FOR THE 00Z AVIATION DISCUSSION.
AVIATION...STRONG SE WINDS GUSTING UP TO 35 KTS WILL BEGIN TO
DECOUPLE SLIGHTLY THIS EVENING OVER ALI-CRP-VCT...HOWEVER ARE
EXPECTED TO REMAIN PAST 06Z FOR LRD AS THE LLJ DEVELOPS. ELEVATED
WINDS OVERNIGHT WILL PRECLUDE THE MENTION OF LLWS IN THE TAFS.
MVFR CIGS BEGINNING TO DEVELOP ALONG THE COAST...WITH ALL SITES
AT MVFR AFTER 06Z WITH HEIGHTS AROUND 2K FEET. MODELS WERE HINTING
AT DEVELOPMENT OF THUNDERSTORMS OUT WEST MOVING S-SE AFFECTING
LRD BTWN 03Z-06Z...HOWEVER AM THINKING INSTABILITY WILL BE LESS
WITH THE BEST UPPER DYNAMICS REMAINING WELL TO THE NORTH...WHICH
SHOULD INHIBIT DEVELOPMENT IN SOUTH TEXAS. WILL MONITOR TRENDS.
WINDS WILL AGAIN INCREASE MID-DAY WEDNESDAY...WITH CIGS
TRANSITIONING TO VFR. THE STRONGEST WINDS SHOULD REMAIN AROUND
ALI-CRP...GUSTING UP TO 35KT.
PREV DISCUSSION... /ISSUED 342 PM CDT TUE MAY 28 2013/
SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)...CHANCES FOR
SHOWERS AND THUNDERSTORMS WILL BE THE MAIN CONCERN IN THE SHORT
TERM. WEAKNESS IN FLOW ALOFT JUST NORTHEAST OF THE CWA COMBINED
WITH DAYTIME HEATING HAS RESULTED IN A FEW SHOWERS THIS AFTERNOON
MAINLY EAST OF INTERSTATE 37. MUCH LIKE YESTERDAY...EXPECT THIS
ACTIVITY TO DIMINISH WITH LOSS OF DAYTIME HEATING. HAVE INSERTED A
10 POP WITH MENTION OF SHOWERS THROUGH 00Z TO ACCOUNT FOR THESE
SHOWERS. ATTENTION WILL TURN OUT TO THE WEST LATER THIS EVENING
WHERE LOWER CONFIDENCE OF CONVECTION EXISTS. SHORT TERM GUIDANCE
KEEPS MOST OF THE CONVECTION NORTHWEST OF THE REGION AND OVER
MEXICO. HIGH RES MODELS ALSO SHOW MIXED SIGNALS WRT TO
THUNDERSTORMS OUT WEST. 4KM WRF NMM ORGANIZES LINE OF CONVECTION
ON THE DRYLINE LATER THIS EVENING. STRONG SSE LOW LEVEL JET OF 40
TO 45 KNOTS DEVELOPS THIS EVENING OVER THE AREA SO IT IS POSSIBLE
COMPLEX COULD MAKE IT INTO THE WESTERN ZONES. DESPITE LOWER
CONFIDENCE OF THIS OCCURRING... INCLUDED A 20 POP ACROSS THE
WESTERN PART OF WEBB AND LASALLE COUNTIES. WILL MONITOR CONVECTIVE
TRENDS THROUGH THE EVENING. ANOTHER ROUND OF STRATUS TONIGHT LOOKS
LIKELY AS SOUTHEAST WINDS REMAIN UP...SO WARM TEMPS OVERNIGHT LOWS
ARE EXPECTED IN THE MIDDLE TO UPPER 70S.
POTENT UPPER LEVEL TROUGH MOVES OUT OF THE FOUR CORNERS INTO THE
HIGH PLAINS ON WEDNESDAY. WINDS WILL BE BREEZY TO WINDY DUE TO
STRONG GRADIENT B/W SFC TROUGH OVER THE PLAINS AND HIGH PRESSURE TO
THE EAST. NOT CONFIDENT ON ADVISORY LEVEL WINDS AND WILL DEFER TO
NEXT SHIFT. MODELS PROG MOISTURE TO INCREASE ACROSS SOUTH TEXAS
TOMORROW WITH PW VALUES CLIMBING BETWEEN 1.7 AND 1.9 INCHES. MODELS
DIFFER ON THE AMOUNT OF INSTABILITY WITH THE NAM REMAINING GREATER
WITH MLCAPES AOA 3000 J/KG. WITH SUFFICIENT DYNAMICS PRESENT AS
SHORTWAVE APPROACHES...A STRONG TO POSSIBLY SEVERE STORM THREAT MAY
MATERIALIZE DURING THE AFTERNOON. HAVE RETAINED THE 20 AND 30 POPS
ACROSS THE AREA FOR TOMORROW. AT OR ABOVE NORMAL TEMPS WILL
PERSIST ON WEDNESDAY WITH MID 90S IN THE WEST TO NEAR 90 IN THE
EAST.
MARINE...SMALL CRAFT ADVISORY CONDITIONS WILL CONTINUE OVER THE
BAYS THROUGH THE EARLY EVENING AND OVER THE OPEN GULF WATERS
THROUGH AT LEAST 12Z WEDNESDAY AS A PERSISTENT STRONG ONSHORE FLOW
CONTINUES.
LONG TERM (THURSDAY THROUGH TUESDAY)...MODELS PROG UPPER LEVEL
RIDGE TO BLD ACROSS THE REGION FROM THE W ON THU. THIS WILL LEAD TO
A VERY WARM DAY...ESPECIALLY ACROSS THE W CWA WHERE 700MB TEMPS WILL
BE 13C AND 850MB TEMPS 22C. PRECIP NOT EXPECTED DUE TO THE VERY WARM
MID LEVEL TEMPS AND LIMITED MOISTURE. THE UPPER LEVEL RIDGE IS PRGD
TO FLATTEN OUT FRI/SAT...BUT OVERALL CONDITIONS WILL BE PERSISTENT.
PRECIP CHCS INCREASE ON SUNDAY AS AN UPPER SHORT WAVE TRACKS ACROSS
S TX AND COMBINES WITH DEEPER MOISTURE. MID LEVEL TEMPS ARE ALSO
PROGD TO COOL RESULTING IN A WEAKENING CAP. KEPT A SLIGHT CHC ACROSS
MUCH OF THE CWA BUT ALSO INCREASED POPS TO 30 PERCENT ACROSS THE NE
DUE TO PROXIMITY TO DEEPER MOISTURE AND WEAKEST CAP. MODELS DO NOT
SHOW A LOW LEVEL FOCUS OR BDRY...AND WEAK UPPER LEVEL JET WILL BE
FAR REMOVED FROM S TX...THEREFORE AM NOT EXPECTING SVR AT THIS TIME.
THE LATEST MODEL RUNS PROG THE UPPER SHORT WAVE TO EXIT THE REGION
BY MONDAY BUT GIVEN INCONSISTENCIES FROM RUN TO RUN...KEPT THE
SLIGHT CHC FOR MON.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 91 79 93 78 93 / 30 10 10 10 10
VICTORIA 88 75 88 76 90 / 30 20 10 10 10
LAREDO 97 79 99 79 100 / 20 20 10 10 10
ALICE 91 77 93 76 93 / 30 20 10 10 10
ROCKPORT 84 79 83 79 88 / 30 10 10 10 10
COTULLA 94 76 96 75 98 / 30 20 10 10 10
KINGSVILLE 91 78 92 78 93 / 30 20 10 10 10
NAVY CORPUS 83 79 85 79 87 / 30 10 10 10 10
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 8 AM CDT THIS MORNING FOR THE
FOLLOWING ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT
ARANSAS OUT 20 NM...COASTAL WATERS FROM PORT ARANSAS TO
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM BAFFIN BAY
TO PORT ARANSAS FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS
TO MATAGORDA SHIP CHANNEL FROM 20 TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 4 AM CDT EARLY THIS MORNING FOR THE
FOLLOWING ZONES: BAYS AND WATERWAYS FROM BAFFIN BAY TO PORT
ARANSAS...BAYS AND WATERWAYS FROM PORT ARANSAS TO PORT
O`CONNOR.
&&
$$
MB
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
356 AM CDT WED MAY 29 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 356 AM CDT WED MAY 29 2013
LATEST WATER VAPOR IMAGERY CONTINUED TO SHOW A MESSY PATTERN ACROSS
THE CONUS. A LEADING SHORTWAVE...RESPONSIBLE FOR BRINGING SOME
SCATTERED RAIN SHOWERS TO THE AREA YESTERDAY...WAS MOVING ACROSS
NORTHERN LOWER MICHIGAN/EASTERN UPPER MICHIGAN. TWO MAIN SHORTWAVES
NOTED...ONE MOVING THROUGH WESTERN NEBRASKA AND ANOTHER MOVING
ACROSS NORTHERN TEXAS/WESTERN OKLAHOMA. A TROUGH WAS DIGGING INTO
THE CENTRAL ROCKIES/FOUR CORNERS REGION...ATTEMPTING TO EDGE EAST
INTO THE HIGH PLAINS. SURFACE OBSERVATIONS INDICATED A WARM FRONT
EXTENDING FROM SOUTHERN NEBRASKA NORTHEAST THROUGH SOUTHERN IOWA
INTO NORTHERN ILLINOIS.
THE WARM FRONT IS EXPECTED TO LIFT NORTH TODAY AS THE TROUGH EJECTS
NORTHEAST ACROSS THE CENTRAL PLAINS. SHOWERS AND THUNDERSTORMS ARE
EXPECTED TO DEVELOP ALONG THE FRONT AS IT PUSHES NORTHWARD AND A
SHORTWAVE LIFTS NORTH ACROSS THE UPPER MISSISSIPPI RIVER VALLEY.
THERE IS SOME UNCERTAINTY REGARDING HOW MUCH INSTABILITY BUILDS
ALONG THE FRONT. THE NAM SUGGESTS 0-3 KM MUCAPE VALUES CLIMB INTO
THE 1500 TO 2000 J/KG RANGE THIS AFTERNOON AS WARM...MOIST AIR
SURGES NORTHWARD. THIS SEEMS A BIT AGGRESSIVE GIVEN THE ABUNDANT
CLOUD COVER IN PLACE. ALSO...THE NAM SURFACE DEWPOINTS CLIMB TO
AROUND 70. THE RUC SURFACE DEWPOINTS ARE ALSO WAY TOO HIGH
TODAY...WITH DEWPOINTS CLIMBING INTO THE MID 70S. LOWER TO MID 60S
DEW POINTS ARE MUCH MORE REALISTIC...SO THINKING SURFACE BASED
CAPE VALUES OF AROUND 1000 J/KG IS NOT OUT OF THE QUESTION...BUT
WITH ONLY WEAK 0-6 KM SHEAR. CANNOT RULE OUT AN ISOLATED SEVERE
STORM BUT OVERALL PROBABILITIES APPEAR LOW AT LEAST THROUGH MID
AFTERNOON. WILL HAVE TO KEEP A VERY CLOSE WATCH ON AREAS WEST OF
THE MISSISSIPPI RIVER WHEN THE LOW LEVEL JET INTENSIFIES THIS
EVENING AND 0-1KM SHEAR RAMPS UP. IF STORMS ARE SURFACE BASED OVER
THESE AREAS EARLY THIS EVENING...CANNOT RULE OUT AN ISOLATED
TORNADO MAINLY WEST OF A LAKE CITY...TO HARMONY TO OELWEIN LINE.
WARMER AIR ALOFT MOVES IN...CENTERED AROUND 850 MB...AND SHOULD
EFFECTIVELY CAP THE ATMOSPHERE FOR FURTHER CONVECTIVE DEVELOPMENT
AT LEAST UNTIL 850 MB MOISTURE TRANSPORT KICKS IN LATE THIS
EVENING. SHEAR IS RATHER WEAK...UNTIL THE LOW LEVEL JET GETS GOING
THIS EVENING AND FOCUSES INTO EASTERN SOUTH DAKOTA/SOUTHWEST
MINNESOTA. PLAN ON TEMPERATURES GRADUALLY WARMING THROUGH THE DAY
AS THE FRONT MOVES THROUGH WITH HIGHS TOPPING OUT IN THE UPPER
70S. A FEW LOWER TO MID 80S ARE POSSIBLE OVER PORTIONS OF
NORTHEAST IOWA AND FAR SOUTHWEST WISCONSIN. THE WARM FRONT IS
EXPECTED TO PUSH INTO FAR NORTHERN WISCONSIN THIS EVENING. 850 MB
MOISTURE TRANSPORT IS INITIALLY FOCUSES WEST OF THE FORECAST AREA
EARLY IN THE EVENING BUT THEN SHIFT EAST INTO THE AREA LATE
TONIGHT INTO EARLY THURSDAY MORNING. WILL HAVE TO KEEP A VERY
CLOSE WATCH ON HOW THIS MOISTURE TRANSPORT EVOLVES
TONIGHT...ESPECIALLY ALONG AND WEST OF THE MISSISSIPPI RIVER. AT
THIS TIME...THINKING SHOWERS AND STORMS WILL PUSH INTO AREAS WEST
OF MISSISSIPPI RIVER BEFORE SUNRISE ON THURSDAY.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 356 AM CDT WED MAY 29 2013
ACTIVE SOUTHWEST FLOW ALOFT ACROSS THE FORECAST AREA WILL PRODUCE
WIDESPREAD SHOWERS AND THUNDERSTORMS ON THURSDAY. SEVERAL EMBEDDED
SHORTWAVES WILL MOVE OVER THE REGION THROUGH THE DAY WITH BROAD
MOISTURE TRANSPORT AND LIFT OVER THE REGION. A STRONGER WAVE MOVES
IN LATE THURSDAY AFTERNOON INTO THURSDAY EVENING...WITH SHOWERS
AND STORM PERSISTING. INSTABILITY IS NOT ALL THAT
IMPRESSIVE...GENERALLY IN THE 500 TO 1000 J/KG RANGE. 0-6 KM SHEAR
LOOKS TO HOVER IN THE 30 TO 40 KT RANGE SO CANNOT RULE OUT A FEW
STRONG TO SEVERE THUNDERSTORMS WITH HEAVY RAINFALL...LARGE HAIL
AND DAMAGING WINDS. THE REPEATED ROUND OF SHOWERS AND STORMS OVER
THE AREA WILL INCREASE FLOODING CONCERNS...ESPECIALLY OVER
NORTHEAST IOWA...SOUTHEAST MINNESOTA AND FAR WESTERN WISCONSIN.
RAINFALL AMOUNTS OF 1 TO 2 INCHES ARE POSSIBLE BY THURSDAY NIGHT.
THE TROUGH FINALLY CLOSES INTO AN UPPER LOW OVER WESTERN NORTH
DAKOTA. DESPITE THE WIDESPREAD SHOWERS AND STORMS ACROSS THE AREA
ON THURSDAY...THE WARM SOUTHERLY FLOW WILL ALLOW HIGH TEMPERATURES
TO WARM INTO THE MID TO UPPER 70S. THE UPPER LOW STARTS TO DRIFT
SOUTHEAST LATE THURSDAY NIGHT INTO FRIDAY AS A VIGOROUS SHORTWAVE
PUSHES THROUGH THE PLAINS AND LIFTS NORTHEAST INTO THE UPPER AND
MID MISSISSIPPI RIVER VALLEY. AS THIS WAVE MOVES IN ON FRIDAY 0-6
KM BULK SHEAR REALLY RAMPS UP FRIDAY AFTERNOON...45 TO 55 KTS
ACROSS MUCH OF THE FORECAST AREA. HOWEVER...A BOUNDARY PUSHES
ACROSS THE AREA LATE THURSDAY NIGHT INTO FRIDAY MORNING PUSHING
THE BEST INSTABILITY JUST SOUTHEAST OF THE FORECAST AREA..ACROSS
PORTIONS OF FAR EASTERN IOWA THROUGH NORTHERN ILLINOIS AND
SOUTHEAST WISCONSIN. CANNOT RULE OUT SEVERE STORMS ON FRIDAY BUT
THE HIGHER CHANCES LOOK TO BE SOUTHEAST OF THE AREA. PORTIONS OF
FAR NORTHEAST IOWA...AND EXTREME SOUTHWEST WISCONSIN COULD BE
IMPACTED. WILL HAVE TO KEEP A VERY CLOSE WATCH OVER THE NEXT FEW
FORECAST MODELS RUNS TO SEE EXACTLY WHERE THE BOUNDARY WILL SET
UP. SHOWER AND THUNDERSTORMS CHANCES CONTINUE INTO SATURDAY AS THE
UPPER LOW DRIFTS ACROSS WISCONSIN. RAIN CHANCES WILL CONTINUE INTO
SUNDAY AS A TROUGH REMAINS OVER THE GREAT LAKES REGION. AN
UNSEASONABLY COLD AIRMASS MOVES INTO THE REGION SUNDAY INTO MONDAY
WITH STANDARDIZED 850 MB TEMPERATURE ANOMALIES OF -1.5. WOULD
EXPECT OVERNIGHT LOWS ON SUNDAY TO FALL INTO THE UPPER 30S OVER
FAR NORTHERN WISCONSIN...FALLING INTO THE LOWER 40S ACROSS CENTRAL
WISCONSIN AND THE UPPER 40S ACROSS NORTHEAST IOWA. LOCATIONS ALONG
AND NORTH OF THE INTERSTATE 94 CORRIDOR COULD SEE SOME AREAS OF
FROST. HIGH PRESSURE SLIDES EAST OF THE REGION LATE MONDAY NIGHT
INTO TUESDAY AS A TROUGH PUSHES THROUGH THE NORTHERN PLAINS. A
WARM FRONT LOOKS TO LIFT INTO THE UPPER MISSISSIPPI RIVER VALLEY
LATE MONDAY NIGHT INTO TUESDAY BRINGING A CHANCE OF SHOWERS AND
THUNDERSTORMS TO THE AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1141 PM CDT TUE MAY 28 2013
A COUPLE OF ISSUES FOR THE FORECAST.
THE FIRST IS ON THE LOW CLOUDS WHICH ARE STUCK OVER THE TAF
SITES...DUE TO A COMBINATION OF THE RECENT WET WEATHER AND A RIDGE
OF HIGH PRESSURE IN PLACE PROVIDING NO MIXING. NIGHTTIME COOLING
SHOULD ALLOW CEILINGS AND VISIBILITIES TO LOWER DURING THE NEXT
COUPLE HOURS...WITH KRST POSSIBLY SEEING LIFR/VLIFR CONDITIONS IN
THE 10-13Z PERIOD. THE VALLEY LOCATION OF KLSE SHOULD PREVENT
VISIBILITIES DROPPING BELOW MVFR AND CEILINGS BELOW IFR. AFTER
13Z...INCREASING SOUTH TO SOUTHEAST WINDS PLUS DAYTIME HEATING
WILL ALLOW CEILINGS AND VISIBILITIES TO QUICKLY RISE AT BOTH
SITES...AT LEAST TO MVFR BY LATE MORNING AND VFR EARLY IN THE
AFTERNOON.
THE NEXT CONCERN IS ON SHOWER AND THUNDERSTORM CHANCES. A WARM
FRONT NEAR I-70 IN KANSAS AND MISSOURI IS FORECAST TO LIFT INTO
THE TAF SITES EARLY THIS AFTERNOON. FORCING ON THIS FRONT COMBINED
WITH DAYTIME HEATING SHOULD ALLOW FOR SHOWERS AND THUNDERSTORMS
ALONG THIS FRONT. VISIBILITIES COULD BE REDUCED BUT HARD TO PIN
THAT DOWN AT EITHER TAF SITES RIGHT NOW...SINCE A WIDESPREAD BAND
OF SHOWERS AND THUNDERSTORMS IS NOT EXPECTED ON THE FRONT. BRIEF
HEAVY RAIN AND LIGHTNING APPEARS TO BE THE MAIN HAZARDS WITH THE
STORMS. THESE SHOWERS AND THUNDERSTORMS SHOULD END AROUND 00Z
WITH THE PASSAGE OF THE FRONT.
THE FINAL CONCERN IS ON WINDS. DAYTIME MIXING BEHIND THE WARM
FRONT SHOULD ALLOW SOUTHERLY GUSTS OF 20-30 KT TO DEVELOP DURING
THE AFTERNOON AT BOTH TAF SITES...STRONGEST AT KRST. THERE MAY
EVEN BE A PERIOD OF GREATER THAN 30 KT GUSTS AT KRST IN THE 21-00Z
PERIOD. ANTICIPATING WINDS TO STAY GUSTY AT KRST THROUGH THE
EVENING AS A LOW LEVEL JET CROSSES. SHOULD GUSTS DROP OFF...LOW
LEVEL WIND SHEAR WOULD OCCUR. THE LOW LEVEL JET IS NOT AS STRONG
AT KLSE...SO EVEN THOUGH GUSTS SHOULD DROP OFF THERE BEING IN THE
VALLEY...HAVE NOT INCLUDED LOW LEVEL WIND SHEAR AT THIS TIME.
&&
.HYDROLOGY...TODAY THROUGH FRIDAY
ISSUED AT 356 AM CDT WED MAY 29 2013
PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED ACROSS MUCH OF THE
REGION THROUGH FRIDAY. THE HEAVIEST RAIN IS EXPECTED TO FALL FROM
THURSDAY INTO FRIDAY. TOTAL RAINFALL FROM TODAY THROUGH FRIDAY
COULD RANGE FROM 1 TO 3 INCHES WITH LOCALLY HIGHER AMOUNTS
POSSIBLE. THIS COULD LEAD TO FLASH FLOODING AS WELL AS RISES AND
POSSIBLE FLOODING ON AREA RIVERS. A FLASH FLOOD WATCH MAY BE
NEEDED FOR THE AREA IF DETAILS BECOME CLEARER ON WHERE AND WHEN
THE HEAVIEST RAIN WILL FALL.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION...AJ
HYDROLOGY...WETENKAMP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1141 PM CDT TUE MAY 28 2013
.UPDATE...
ISSUED AT 935 PM CDT TUE MAY 28 2013
CONVECTION AS ANTICIPATED INITIATED AND PERSISTS FROM KANSAS INTO
NORTHERN MISSOURI...SOUTHERN IOWA AND NORTHERN ILLINOIS. THIS
CONVECTION FORMED ON OR JUST TO THE NORTH OF A SURFACE WARM
FRONTAL BOUNDARY...WHICH HAS BEEN SLOWLY SHIFTING BACK SOUTH DUE
TO CONVECTIVE OUTFLOWS. 850MB RADAR AND VWP DATA SHOWED SOUTHWEST
35-45 KT WINDS FROM EASTERN KANSAS INTO SOUTHERN WISCONSIN...
PUMPING GULF OF MEXICO MOISTURE INTO THIS CONVECTION. THE FORECAST
AREA LIES ON THE SUBSIDENT SIDE OF THE CONVECTION...AS WELL AS IN
RIDGING BUILDING IN BEHIND A SHORTWAVE IN NORTHERN WISCONSIN. AS A
RESULT...DRY CONDITIONS ARE OCCURRING OVER THE FORECAST AREA.
NUMEROUS HRRR RUNS...INCLUDING THE LATEST AVAILABLE 29.00Z
HRRR...CONTINUE TO DEPICT A DRY FORECAST FOR THE AREA THROUGH 12Z
AND EVEN BEYOND. THE 28.00Z NSSL WRF-ARW ALSO DEPICTS A DRY
FORECAST...WITH BOTH MODELS SUGGESTING ALL CONVECTION STAYS HUNG
UP ACROSS SOUTHERN IOWA OR POINTS SOUTH. THIS MAKES SENSE GIVEN
THE DRIFT SOUTH OF THE WARM FRONT FROM OUTFLOWS...THOUGH THE DRIFT
SOUTH MAY BEGIN TO STOP SOON WITH UPPER RIDGING BUILDING ACROSS
THE CENTRAL AND SOUTHERN PLAINS. ADDITIONALLY...UPPER RIDGING
BUILDING IN BEHIND THE SHORTWAVE HEADING INTO NORTHERN WISCONSIN
SHOULD PROVIDE ADDED SUBSIDENCE. THUS...WENT WITH A DRY FORECAST
THROUGH 12Z.
WILL DEFINITELY HAVE TO WATCH THE FOG SITUATION OVERNIGHT.
TEMP/DEWPOINT SPREADS ARE ALREADY FAIRLY LOW...ESPECIALLY NORTH
OF I-90. SO FAR VISIBILITIES ARE BEHAVING...STAYING AT 4-5 MILES
OR HIGHER. COMBINATION OF BLOWOFF FROM CONVECTION TO THE SOUTH AND
LOW CLOUDS SHOULD PRECLUDE GOOD RADIATIONAL COOLING TO FORM FOG.
THUS...TO GET DENSE FOG...WE WILL NEED CEILINGS TO LOWER.
CONFIDENCE IS TOO LOW TO PUT OUT A DENSE FOG ADVISORY NOW...BUT
CANNOT RULE OUT ONE NEEDED LATER.
&&
.SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT)
ISSUED AT 325 PM CDT TUE MAY 28 2013
MAIN FORECAST CONCERNS THIS PERIOD...SHRA/TSRA CHANCES THRU THE
PERIOD...RAIN AMOUNTS/SEVERE THREAT WED AFTERNOON/EVENING.
18Z DATA ANALYSIS HAD A WARM/STATIONARY FRONT NEAR THE WI/IL
BORDER...SOUTHWEST TO A LOW OVER NORTHEAST NM. WV IMAGERY AND EVEN
IR/VIS IMAGERY DEPICTED A RATHER VIGOROUS MID LEVEL SHORTWAVE MOVING
EAST ACROSS SOUTHWEST MN. NORTH OF THE FRONT AND AHEAD OF THE
SHORTWAVE...LOW CLOUDS...PATCHY BR/-DZ PERSISTED ACROSS MUCH OF
MN/WI. ACROSS MUCH OF IA...IN THE WAKE OF A SHORTWAVE THAT PASSED
EARLY THIS MORNING...CLOUDS WERE A LITTLE THINNER WITH SOME
SUNSHINE IN THE SUBSIDENCE BEHIND THAT SHORTWAVE. ACROSS MUCH OF
MN/WI WHERE THE LOW CLOUDS/LACK OF SUNSHINE PERSISTED...MID-DAY
TEMPS REMAINED COOL...IN THE 50S TO LOW 60S.
SOME MINOR DIFFERENCES NOTED WITH 28.12Z MODEL INITIALIZATIONS...
BUT THE BIG PICTURE OF THE SOLUTIONS REMAINS QUITE SIMILAR THRU WED
NIGHT AND INTO FRIDAY. THERE WILL BE PERIODS/BREAKS FROM THE RAIN BUT
BETWEEN TONIGHT AND FRI ANOTHER COUPLE ROUNDS OF HEAVIER/MORE
WIDESPREAD RAIN LOOK TO SPREAD ACROSS THE AREA. DPROG/DT OF 500MB
HGTS AT 28.12Z SHOWED THE MODEL RUNS OF 26.12Z AND 27.12Z VERIFIED
QUITE WELL ACROSS NOAM/EASTERN PAC WHILE TRENDING TOWARD A TIGHTER...
COMMON CONSENSUS. SOLUTIONS CONTINUE TO CONVERGE TOWARD A TIGHTER...
COMMON CONSENSUS TONIGHT/WED AS HGTS RISE OVER THE REGION AND STRONG
TROUGHING DIGS THRU THE ROCKIES. IMPROVING CONSENSUS WED NIGHT AS
THE STRONG TROUGHING MOVES INTO THE CENTRAL CONUS. CHECK OF OBS
VS. MODEL DATA AT 18Z SHOWED THEM TO BE REASONABLE WITH THE CENTRAL
CONUS MASS FIELDS...THOUGH NAM/GEM WERE A BIT HIGH WITH SFC DEW
POINTS OVER MUCH OF IL. A BLEND OF THE MODELS LOOKED BEST WITH THE
12-18Z PRECIP OVER THE UPPER MIDWEST. NO CLEAR MODEL FAVORITE AND
PREFERRED A MODEL/ENSEMBLE CONSENSUS. SHORT-TERM FCST CONFIDENCE ON
THE GOOD SIDE THIS CYCLE.
FOR THE SHORT TERM...SOUTHWEST MN SHORTWAVE WILL PASS THIS EVENING...
TAKING SOME OF THE DEEPER MOISTURE/FORCING/LIFT WITH IT. LITTLE IN TH
WAY OF FORCING/LIFT SEEN FOR SHRA/TSRA CHANCES AFTER ABOUT 03Z. SOME
WEAK LOWER LEVEL WARM ADVECTION CONTINUES BUT MOST OF THIS LOOKS TO
GO INTO WARMING/RISING MID LEVEL HGTS BEHIND THE SHORTWAVE. LEFT SOME
SMALL -SHRA/ISOLATED TSRA CHANCES IN THE FCST GRIDS TONIGHT...MAINLY
ACROSS THE SOUTHEAST HALF OF THE FCST AREA WHERE SOME 500-1000 J/KG
MU CAPE LOOKS TO REMAIN THRU THE NIGHT...AND BLENDS WELL WITH
NEIGHBORING GRIDS. VIS IMAGERY SHOWS THERE SHOULD BE SOME DECREASE OF
CLOUDS IN THE WAKE OF THE SHORTWAVE FOR LATER THIS EVENING/OVERNIGHT.
WITH THE VERY MOIST BOUNDARY LAYER AND LIGHT WINDS...AREAS/PATCHY
FOG SHOULD FORM...ESPECIALLY WHERE CLOUDS/LIGHT PRECIP HELD TEMPS
DOWN TODAY.
THE FRONTAL BOUNDARY GETS A PUSH NORTHWARD ON WED AS THE ROCKIES
TROUGHING MOVES INTO THE PLAINS AND DEEPER/STRONGER SOUTHERLY FLOW
DEVELOPS OVER THE MID/UPPER MS VALLEY. PW VALUES IN THE AIRMASS
BEING PUSHED INTO/OVER THE WARM FRONT IN THE 1.5 TO 1.75 INCH RANGE
ON NOSE OF 35-50KT 850MB JET/MOISTURE TRANSPORT/THETA-E CONVERGENCE.
1K-2K J/KG MU CAPE INDICATED AS WELL IN THIS AIRMASS. RAISED SHRA/
TSRA CHANCES FOR WED INTO THE 70-80 PERCENT RANGE AS THE WARM FRONT
LIFTS NORTH INTO THE AREA. INCREASING WIND FLOW SHOULD KEEP ANY TSRA
PROGRESSIVE ON WED. WITH A BREAK TONIGHT AND PLENTY OF MODEL DETAIL
DIFFERENCES WITH PRECIP AMOUNTS WED...HELD OFF ON RE-ISSUING A FLASH
FLOOD WATCH ON WED FOR NOW. AREA LOOKS TO GET ANOTHER BREAK FROM THE
MORE WIDESPREAD SHRA/TSRA WED NIGHT WITH THE WARM FRONT LIFTING
NORTH OF THE AREA AND THE PLAINS LOW COLD FRONT AND NEXT ROUND OF
STRONGER/LARGER SCALE FORCING REMAINING WELL WEST OF THE AREA.
ONE OF THE BIGGER CONCERNS IS HIGHS ON WED. MUCH OF THE GUIDANCE IS
STILL PUSHING WED HIGHS INTO THE UPPER 70S/LOW 80S. WITH SHRA/TSRA
LIKELY TO DELAY THE WARM FRONT LIFTING THRU THE AREA...PLUS PLENTY
OF CLOUDS AND THE SHRA/TSRA...LOWERED HIGHS FOR WED MOSTLY INTO THE
MID 70S...AND EVEN THIS MAY STILL BE 5-10F TOO WARM. HIGHS WED WILL
IMPACT HOW MUCH CAPE DEVELOPS OVER THE AREA AND ANY SEVERE STORM
THREAT. PROXIMITY OF THE WARM FRONT AND ENHANCED LOW LEVEL HELICITY
MAY ALLOW SEVERE STORMS TO DEVELOP...IF THEY CAN GET ROOTED IN THE
BOUNDARY LAYER. SEE SWODY2 FOR MORE DETAILS OF THE WED SEVERE THREAT.
FOR NOW WED HIGHS IN THE MID 70S BLEND WELL WITH NEIGHBORING GRIDS.
USED A BLEND OF GUIDANCE LOWS FOR TONIGHT/WED NIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 325 PM CDT TUE MAY 28 2013
FORECAST CONCERNS THU INTO FRI ARE SHRA/TSRA CHANCES AND POTENTIAL
FOR HEAVY RAINS/SEVERE STORMS AS THE COLD FRONT MOVES THRU THE AREA.
MODELS STAY IN REASONABLE AGREEMENT THU/FRI AS THE PLAINS TROUGH
LIFTS NORTH THU..THEN DEVELOPS A 500MB LOW OVER THE DAKOTAS BY FRI.
RATHER ENERGETIC SYSTEM DEVELOPS A STRONG SFC LOW OVER THE DAKOTAS
BY MID-DAY THU. SFC SYSTEM OCCLUDES AND PUSHES THE COLD FRONT TOWARD
THE AREA THU THEN INTO THE AREA THU NIGHT. THIS INTO THE AIRMASS WITH
1K-2K J/KG MU CAPE AND 1.5 TO 1.75 INCH PW VALUES...ALONG WITH
STRENGTHENING WIND FIELDS. SWODY3 QUITE REASONABLE AT THIS TIME.
POTENTIAL REMAINS FOR REPEAT STRONGER...HEAVY RAIN PRODUCING TSRA
THU/THU EVENING AND APPEARS ANOTHER FLASH FLOOD WATCH WILL BE NEEDED
FOR THIS TIME PERIOD. WILL CONTINUE ESFARX ADDRESSING THIS POTENTIAL
FOR NOW AND GIVE CREWS TONIGHT/WED A COUPLE MORE MODEL RUNS TO
DETAIL WHERE ANY FLASH FLOOD WATCH MAY BE NEEDED. RAISED SHRA/TSRA
CHANCES FOR THU/THU EVENING INTO THE 70-80 PERCENT RANGE FOR MUCH OF
THE AREA. WITH THE MID LEVEL TROUGH AXIS REMAINING WEST OF THE AREA
AND WHAT LOOKS TO BE A SECOND SFC COLD FRONT/TROUGH TO PUSH TOWARD
THE AREA...CONTINUED SHRA/TSRA CHANCES FRI/FRI NIGHT LOOK GOOD. GIVEN
SOME TIMING DIFFERENCES...USED THE MODEL/ENSEMBLE CONSENSUS GUIDANCE
FOR HIGHS/LOWS THU THRU FRI NIGHT.
MEDIUM RANGE MODEL RUNS OF 28.00Z AND 28.12Z IN REASONABLY GOOD
AGREEMENT WITH EACH OTHER AND OFFER AN IMPROVING CONSENSUS OVER
THEIR PREVIOUS RUNS FOR SAT THRU MON. THIS AS THE MID TROUGH
SWINGS ACROSS THE UPPER MIDWEST SAT/SAT NIGHT AND SHORTWAVE
RIDGING BUILDS IN BY LATER SUN AND FOR MON. LESSER CONSISTENCY BY
TUE...BUT A SIGNAL FOR ANOTHER STRONGER SHORTWAVE TROUGH TO BE
MOVING THRU THE NORTHERN ROCKIES... PUSHING THE SHORTWAVE RIDGE
AXIS INTO THE EASTERN GREAT LAKES. FCST CONFIDENCE AVERAGE TO GOOD
SAT-MON THEN AVERAGE BY TUE.
WITH THE MID LEVEL TROUGH AXIS STILL WEST OF THE AREA SAT...COOL/
COOLING 850- 500MB TEMPS/STEEPER MID LEVEL LAPSE RATES AND PW
VALUES REMAINING AROUND AN INCH...SHRA/TSRA CHANCES LOOKING TO
LINGER ON SAT. TROUGH AXIS PASSES LATE SAT NIGHT/EARLY SUN FOR
WHAT LOOKS TO BE A MUCH NEEDED DRIER PERIOD SUN AND ESPECIALLY MON
AS CAN HIGH PRESSURE AND THE SHORTWAVE RIDGING ALOFT BUILD EAST
INTO THE WESTERN GREAT LAKES.
NEXT TROUGH CROSSING THE ROCKIES MON NIGHT/TUE DEVELOPS LOW
PRESSURE IN THE CENTRAL/NORTHERN PLAINS...WITH INCREASING SOUTH/
SOUTHWEST FLOW...PW VALUES AND MOISTURE TRANSPORT/THETA-E CONVERGENCE
INTO THE UPPER MIDWEST ON TUE. SHRA/TSRA CHANCES LOOKING TO ALREADY
RETURN ON TUE. MODEL/ENSEMBLE CONSENSUS FOR HIGHS/LOWS SAT-TUE
APPEAR WELL TRENDED WITH TEMPS REMAINING BELOW TO NEAR NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1141 PM CDT TUE MAY 28 2013
A COUPLE OF ISSUES FOR THE FORECAST.
THE FIRST IS ON THE LOW CLOUDS WHICH ARE STUCK OVER THE TAF
SITES...DUE TO A COMBINATION OF THE RECENT WET WEATHER AND A RIDGE
OF HIGH PRESSURE IN PLACE PROVIDING NO MIXING. NIGHTTIME COOLING
SHOULD ALLOW CEILINGS AND VISIBILITIES TO LOWER DURING THE NEXT
COUPLE HOURS...WITH KRST POSSIBLY SEEING LIFR/VLIFR CONDITIONS IN
THE 10-13Z PERIOD. THE VALLEY LOCATION OF KLSE SHOULD PREVENT
VISIBILITIES DROPPING BELOW MVFR AND CEILINGS BELOW IFR. AFTER
13Z...INCREASING SOUTH TO SOUTHEAST WINDS PLUS DAYTIME HEATING
WILL ALLOW CEILINGS AND VISIBILITIES TO QUICKLY RISE AT BOTH
SITES...AT LEAST TO MVFR BY LATE MORNING AND VFR EARLY IN THE
AFTERNOON.
THE NEXT CONCERN IS ON SHOWER AND THUNDERSTORM CHANCES. A WARM
FRONT NEAR I-70 IN KANSAS AND MISSOURI IS FORECAST TO LIFT INTO
THE TAF SITES EARLY THIS AFTERNOON. FORCING ON THIS FRONT COMBINED
WITH DAYTIME HEATING SHOULD ALLOW FOR SHOWERS AND THUNDERSTORMS
ALONG THIS FRONT. VISIBILITIES COULD BE REDUCED BUT HARD TO PIN
THAT DOWN AT EITHER TAF SITES RIGHT NOW...SINCE A WIDESPREAD BAND
OF SHOWERS AND THUNDERSTORMS IS NOT EXPECTED ON THE FRONT. BRIEF
HEAVY RAIN AND LIGHTNING APPEARS TO BE THE MAIN HAZARDS WITH THE
STORMS. THESE SHOWERS AND THUNDERSTORMS SHOULD END AROUND 00Z
WITH THE PASSAGE OF THE FRONT.
THE FINAL CONCERN IS ON WINDS. DAYTIME MIXING BEHIND THE WARM
FRONT SHOULD ALLOW SOUTHERLY GUSTS OF 20-30 KT TO DEVELOP DURING
THE AFTERNOON AT BOTH TAF SITES...STRONGEST AT KRST. THERE MAY
EVEN BE A PERIOD OF GREATER THAN 30 KT GUSTS AT KRST IN THE 21-00Z
PERIOD. ANTICIPATING WINDS TO STAY GUSTY AT KRST THROUGH THE
EVENING AS A LOW LEVEL JET CROSSES. SHOULD GUSTS DROP OFF...LOW
LEVEL WIND SHEAR WOULD OCCUR. THE LOW LEVEL JET IS NOT AS STRONG
AT KLSE...SO EVEN THOUGH GUSTS SHOULD DROP OFF THERE BEING IN THE
VALLEY...HAVE NOT INCLUDED LOW LEVEL WIND SHEAR AT THIS TIME.
&&
.HYDROLOGY...TONIGHT THROUGH FRIDAY
ISSUED AT 325 PM CDT TUE MAY 28 2013
A COUPLE ROUNDS OF MORE WIDESPREAD SHRA/TSRA ARE EXPECTED FROM
WEDNESDAY THROUGH FRIDAY AND A FLASH FLOOD WATCH WILL LIKELY BE
NEEDED DURING SOME PORTION OF THIS TIME-FRAME. THE FIRST ROUND COMES
WED AS A WARM FRONT LIFTS INTO/ACROSS THE AREA...WITH WHAT LOOKS TO
BE MORE PROGRESSIVE SHRA/TSRA AND MOST RAIN AMOUNTS IN THE 0.25 TO
0.5 INCH RANGE. THE SECOND MORE WIDESPREAD ROUND OF SHRA/TSRA MOVES
ACROSS THE AREA THU/THU EVENING...AHEAD OF A COLD FRONT. THERE IS
MORE POTENTIAL FOR REPEAT...HEAVY RAIN PRODUCING TSRA THU/THU
EVENING GIVEN THE WIND FIELDS AND SLOWER MOVING FRONT. RAIN AMOUNTS
OF 1 TO 2 INCHES...WITH LOCALLY HEAVIER AMOUNTS...ARE QUITE POSSIBLE
THU/THU NIGHT. A FLASH FLOOD WATCH WILL MORE LIKELY BE NEEDED FOR
PORTIONS OF THE AREA WITH THIS ROUND OF SHRA/TSRA. LARGER RIVERS WILL
ALSO SEE CONTINUED RISES AND POSSIBLE FLOODING THIS WEEK WITH THE
PROLONGED PERIOD OF COOL/WET WEATHER. CONTINUE TO MONITOR RIVER
FORECASTS AND STATEMENTS CLOSELY THIS WEEK.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...AJ
SHORT TERM...RRS
LONG TERM....RRS
AVIATION...AJ
HYDROLOGY....RRS
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1157 PM MDT TUE MAY 28 2013
.UPDATE...
ISSUED AT 1008 PM MDT TUE MAY 28 2013
WENT AHEAD AND LET THE SEVERE THUNDERSTORM WATCH EXPIRE ON TIME AT
10 PM THIS EVENING FOR THE PANHANDLE. THERE ARE STILL SOME
THUNDERSTORMS OVER THE SOUTHERN PANHANDLE COMING IN FROM NORTHEAST
COLORADO...BUT THE ATMOSPHERE HAS BEEN WORKED OVER BY NUMEROUS
THUNDERSTORMS...SO DO NOT EXPECT STORMS TO BECOME SEVERE AGAIN.
WILL NEED TO WATCH EASTERN LARAMIE COUNTY LATE THIS EVENING AS
STORMS MOVE NORTH OUT OF COLORADO. LATEST RUC CAPE HAS AROUND 600
J/KG WITH CLOSE TO 900 J/KG UP NEAR BORDEAUX. KEPT THE RELATIVELY
HIGH POPS...40 PERCENT OR SO...FOR THE OVERNIGHT HOURS.
FRONT/DRYLINE PUSHES EAST INTO CENTRAL NEBRASKA BY LATE MORNING.
SEVERE THUNDERSTORMS SHOULD BE WELL EAST OF THE FORECAST AREA FOR
WEDNESDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY EVENING) ISSUED AT
247 PM MDT TUE MAY 28 2013
CURRENT KCYS RADAR LOOP SHOWS THUNDERSTORMS JUST STARTING TO
DEVELOP ACROSS THE HIGH PLAINS OF SOUTHEAST WYOMING AND INTO
WESTERN NEBRASKA. THERE IS STILL A SLIGHT CHANCE OF SEVERE
THUNDERSTORMS LATE THIS AFTERNOON THROUGH TONIGHT...BUT WITH HIGH
LEVEL CLOUDS PUSHING ACROSS THE EASTERN PLAINS FROM THIS
MORNING...CHANCES ARE A LITTLE LESS THAN EARLIER ANTICIPATED.
COVERAGE OF SHOWERS AND THUNDERSTORMS WILL INCREASE THROUGH THIS
AFTERNOON WITH SOME MODERATE TO HIGH RAINFALL AMOUNTS POSSIBLE
OVER FAR EASTERN WYOMING AND WESTERN NEBRASKA...WHERE LOCAL
AMOUNTS MAY BE AROUND 1 INCH. MAIN THREATS FROM THESE
THUNDERSTORMS WILL BE HAIL...GUSTY WINDS...AND FREQUENT LIGHTNING.
OFF AND ON SHOWERS AND TSTORMS WILL CONTINUE THROUGH TONIGHT ACROSS
THE HIGH PLAINS WITH THE BEST CHANCE ACROSS WESTERN NEBRASKA. THIS
ACTIVITY WILL BE ASSOCIATED WITH THE TROUGH AXIS BEGINNING TO PUSH
ACROSS THE ROCKIES TONIGHT AS IT BECOMES NEGATIVELY TILTED.
THUNDERSTORM POTENTIAL WILL BE LESS ON WEDNESDAY AS COOLER AIR
MOVES INTO THE AREA...ALTHOUGH LOCATIONS EAST OF THE
NEBRASKA/WYOMING BORDER HAVE THE BEST POTENTIAL TO SEE STRONG OR
SEVERE STORMS AS THE TROUGH AXIS WILL BE RIGHT OVER SOUTHEAST
WYOMING WEDNESDAY AFTERNOON. FORECAST FOR SOUTHEAST WYOMING WILL
BE TRICKY WITH THE TROUGH AXIS OVERHEAD AND DOWNSLOPE WINDS JUST
BEHIND THE TROUGH. THE NAM AND GEM SHOW RAIN SHOWERS AND EMBEDDED
THUNDER ACROSS SOUTHEAST WYOMING WITH SOME PRETTY GOOD QPF AMOUNTS
WHILE THE GFS AND ECMWF ARE ON THE DRY SIDE WITH LOW DEWPOINTS.
KEPT THE HIGHEST POP FROM NIOBRARA COUNTY SOUTHEAST INTO THE
NORTHERN PANHANDLE OF NEBRASKA. BELIEVE IT WILL BE TOUGH TO AVOID
CONVECTIVE ACTIVITY EVEN ACROSS SOUTHEAST WYOMING...SO INCREASED
POP BETWEEN 30 TO 60 PERCENT ALONG I25 AND I80 AS WELL.
PRECIPITATION WILL PUSH NORTH AS THE TROUGH BECOMES A CLOSED LOW
NORTHEAST OF THE FORECAST AREA OVER THE DAKOTAS. EXPECT DRIER AIR
TO PUSH INTO THE SOUTHERN HALF OF THE FORECAST AREA ALONG I80
WEDNESDAY NIGHT AND THURSDAY. INCREASED TEMPERATURES ON THURSDAY
AND BELIEVE IT WILL BE A LITTLE BIT WARMER COMPARED TO WEDNESDAY
DUE TO DOWNSLOPE WINDS AND ADIABATIC WARMING. TEMPERATURES WILL BE
IN THE 60S TO LOW 70S OVER MOST OF THE AREA WITH PERHAPS MID TO
UPPER 50S ACROSS THE HIGH VALLEYS WEST OF THE LARAMIE RANGE.
.LONG TERM...(FRIDAY THROUGH TUESDAY) ISSUED AT 220 PM MDT TUE
MAY 28 2013
WINDY AND A LITTLE COOLER CONDITIONS FOR FRIDAY AS SFC/UPPER LOW
MOVE SLOWLY EAST OVER THE DAKOTAS. MAIN DIFFICULTY WILL BE HOW MUCH
WRAP AROUND SHOWERS PROGRESS SOUTH INTO THE CWA. BEST CHANCES OVER
THE NORTH AND HAVE TAILORED POPS THIS WAY. NEXT PUSH OF COOLER AIR
WILL SINK OVER THE AREA LATE FRIDAY COOLING THINGS A LITTLE MORE
FOR SATURDAY ALONG WITH WIDELY SCATTERED SHOWERS...POSSIBLY A
LITTLE MORE WIDESPREAD. DRY AND WARMER CONDITIONS RETURN SUNDAY
AND MONDAY AS A SHORT UPPER RIDGE MOVES BY. UPPER TROF THEN
SETTLES OVER THE PACIFIC NW EARLY NEXT WEEK WITH SW FLOW ALOFT
BECOMING ESTABLISHED OVER THE CWA BY LATE MONDAY. CHANCES FOR
WIDELY SCTD SHOWERS AND TSTRMS INCREASE A BIT TUESDAY AS MOISTURE
AND INSTABILITY INCREASE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY EVENING)
ISSUED AT 1152 PM MDT TUE MAY 28 2013
ISOLATED TO SCATTERED SHOWERS WILL CONTINUE ACROSS MAINLY THE
NEBRASKA PANHANDLE THROUGH AROUND 10Z. THERE COULD BE SOME GUSTY
AND ERRATIC WINDS WITH THE STRONGER STORMS. MODELS HAVE SHOWERS
OVER PORTIONS OF SOUTHEAST WY BETWEEN AROUND 09Z AND MID-MORNING.
THIS ACTIVITY SHIFTS EASTWARD INTO THE PANHANDLE DURING THE
AFTERNOON...AND ISOLATED THUNDERSTORMS WILL BE POSSIBLE OVER THE
NEBRASKA SITES WITH MORE INSTABILITY. OUTSIDE OF SOME LOCALIZED
MVFR CIGS...VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH THE TAF
PERIOD.
&&
.FIRE WEATHER...
ISSUED AT 155 PM MDT TUE MAY 28 2013
CHANCES FOR MORE WIDESPREAD RAINFALL AND WETTING RAINS WILL
INCREASE DURING THE NEXT 12 TO 48 HOURS AS A PACIFIC STORM SYSTEM
MOVES ACROSS THE CENTRAL ROCKIES AND ADJACENT PLAINS. FUELS IN
GREEN UP STAGE...COOLER TEMPERATURES AND HIGHER RELATIVE
HUMIDITIES WILL RESULT IN NO FIRE WEATHER CONCERNS THROUGH THE END
OF THE WEEK. WARMER AND DRIER CONDITIONS WILL RETURN EARLY NEXT
WEEK.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...CLAYCOMB
SHORT TERM...TJT
LONG TERM...RE
AVIATION...FINCH
FIRE WEATHER...TJT
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1037 PM MDT TUE MAY 28 2013
.UPDATE...
ISSUED AT 1008 PM MDT TUE MAY 28 2013
WENT AHEAD AND LET THE SEVERE THUNDERSTORM WATCH EXPIRE ON TIME AT
10 PM THIS EVENING FOR THE PANHANDLE. THERE ARE STILL SOME
THUNDERSTORMS OVER THE SOUTHERN PANHANDLE COMING IN FROM NORTHEAST
COLORADO...BUT THE ATMOSPHERE HAS BEEN WORKED OVER BY NUMEROUS
THUNDERSTORMS...SO DO NOT EXPECT STORMS TO BECOME SEVERE AGAIN.
WILL NEED TO WATCH EASTERN LARAMIE COUNTY LATE THIS EVENING AS
STORMS MOVE NORTH OUT OF COLORADO. LATEST RUC CAPE HAS AROUND 600
J/KG WITH CLOSE TO 900 J/KG UP NEAR BORDEAUX. KEPT THE RELATIVELY
HIGH POPS...40 PERCENT OR SO...FOR THE OVERNIGHT HOURS.
FRONT/DRYLINE PUSHES EAST INTO CENTRAL NEBRASKA BY LATE MORNING.
SEVERE THUNDERSTORMS SHOULD BE WELL EAST OF THE FORECAST AREA FOR
WEDNESDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY EVENING) ISSUED AT
247 PM MDT TUE MAY 28 2013
CURRENT KCYS RADAR LOOP SHOWS THUNDERSTORMS JUST STARTING TO
DEVELOP ACROSS THE HIGH PLAINS OF SOUTHEAST WYOMING AND INTO
WESTERN NEBRASKA. THERE IS STILL A SLIGHT CHANCE OF SEVERE
THUNDERSTORMS LATE THIS AFTERNOON THROUGH TONIGHT...BUT WITH HIGH
LEVEL CLOUDS PUSHING ACROSS THE EASTERN PLAINS FROM THIS
MORNING...CHANCES ARE A LITTLE LESS THAN EARLIER ANTICIPATED.
COVERAGE OF SHOWERS AND THUNDERSTORMS WILL INCREASE THROUGH THIS
AFTERNOON WITH SOME MODERATE TO HIGH RAINFALL AMOUNTS POSSIBLE
OVER FAR EASTERN WYOMING AND WESTERN NEBRASKA...WHERE LOCAL
AMOUNTS MAY BE AROUND 1 INCH. MAIN THREATS FROM THESE
THUNDERSTORMS WILL BE HAIL...GUSTY WINDS...AND FREQUENT LIGHTNING.
OFF AND ON SHOWERS AND TSTORMS WILL CONTINUE THROUGH TONIGHT ACROSS
THE HIGH PLAINS WITH THE BEST CHANCE ACROSS WESTERN NEBRASKA. THIS
ACTIVITY WILL BE ASSOCIATED WITH THE TROUGH AXIS BEGINNING TO PUSH
ACROSS THE ROCKIES TONIGHT AS IT BECOMES NEGATIVELY TILTED.
THUNDERSTORM POTENTIAL WILL BE LESS ON WEDNESDAY AS COOLER AIR
MOVES INTO THE AREA...ALTHOUGH LOCATIONS EAST OF THE
NEBRASKA/WYOMING BORDER HAVE THE BEST POTENTIAL TO SEE STRONG OR
SEVERE STORMS AS THE TROUGH AXIS WILL BE RIGHT OVER SOUTHEAST
WYOMING WEDNESDAY AFTERNOON. FORECAST FOR SOUTHEAST WYOMING WILL
BE TRICKY WITH THE TROUGH AXIS OVERHEAD AND DOWNSLOPE WINDS JUST
BEHIND THE TROUGH. THE NAM AND GEM SHOW RAIN SHOWERS AND EMBEDDED
THUNDER ACROSS SOUTHEAST WYOMING WITH SOME PRETTY GOOD QPF AMOUNTS
WHILE THE GFS AND ECMWF ARE ON THE DRY SIDE WITH LOW DEWPOINTS.
KEPT THE HIGHEST POP FROM NIOBRARA COUNTY SOUTHEAST INTO THE
NORTHERN PANHANDLE OF NEBRASKA. BELIEVE IT WILL BE TOUGH TO AVOID
CONVECTIVE ACTIVITY EVEN ACROSS SOUTHEAST WYOMING...SO INCREASED
POP BETWEEN 30 TO 60 PERCENT ALONG I25 AND I80 AS WELL.
PRECIPITATION WILL PUSH NORTH AS THE TROUGH BECOMES A CLOSED LOW
NORTHEAST OF THE FORECAST AREA OVER THE DAKOTAS. EXPECT DRIER AIR
TO PUSH INTO THE SOUTHERN HALF OF THE FORECAST AREA ALONG I80
WEDNESDAY NIGHT AND THURSDAY. INCREASED TEMPERATURES ON THURSDAY
AND BELIEVE IT WILL BE A LITTLE BIT WARMER COMPARED TO WEDNESDAY
DUE TO DOWNSLOPE WINDS AND ADIABATIC WARMING. TEMPERATURES WILL BE
IN THE 60S TO LOW 70S OVER MOST OF THE AREA WITH PERHAPS MID TO
UPPER 50S ACROSS THE HIGH VALLEYS WEST OF THE LARAMIE RANGE.
.LONG TERM...(FRIDAY THROUGH TUESDAY) ISSUED AT 220 PM MDT TUE
MAY 28 2013
WINDY AND A LITTLE COOLER CONDITIONS FOR FRIDAY AS SFC/UPPER LOW
MOVE SLOWLY EAST OVER THE DAKOTAS. MAIN DIFFICULTY WILL BE HOW MUCH
WRAP AROUND SHOWERS PROGRESS SOUTH INTO THE CWA. BEST CHANCES OVER
THE NORTH AND HAVE TAILORED POPS THIS WAY. NEXT PUSH OF COOLER AIR
WILL SINK OVER THE AREA LATE FRIDAY COOLING THINGS A LITTLE MORE
FOR SATURDAY ALONG WITH WIDELY SCATTERED SHOWERS...POSSIBLY A
LITTLE MORE WIDESPREAD. DRY AND WARMER CONDITIONS RETURN SUNDAY
AND MONDAY AS A SHORT UPPER RIDGE MOVES BY. UPPER TROF THEN
SETTLES OVER THE PACIFIC NW EARLY NEXT WEEK WITH SW FLOW ALOFT
BECOMING ESTABLISHED OVER THE CWA BY LATE MONDAY. CHANCES FOR
WIDELY SCTD SHOWERS AND TSTRMS INCREASE A BIT TUESDAY AS MOISTURE
AND INSTABILITY INCREASE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY EVENING)
ISSUED AT 1032 PM MDT TUE MAY 28 2013
THROUGH 15Z...AREAS OF IFR AT CHADRON...ALLIANCE AND SIDNEY IN
FOG AND LOW CLOUDS. VFR PREVAILS ELSEWHERE...WITH ISOLATED SHOWERS
AND THUNDERSTORMS ACROSS WESTERN NEBRASKA.
AFTER 19Z...ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS
PRODUCING LOCALIZED MVFR ALONG WITH GUSTY AND ERRATIC WINDS...
WITH VFR PREVAILING. WINDS GUSTING 25 TO 35 KNOTS THROUGH 01Z.
&&
.FIRE WEATHER...
ISSUED AT 155 PM MDT TUE MAY 28 2013
CHANCES FOR MORE WIDESPREAD RAINFALL AND WETTING RAINS WILL
INCREASE DURING THE NEXT 12 TO 48 HOURS AS A PACIFIC STORM SYSTEM
MOVES ACROSS THE CENTRAL ROCKIES AND ADJACENT PLAINS. FUELS IN
GREEN UP STAGE...COOLER TEMPERATURES AND HIGHER RELATIVE
HUMIDITIES WILL RESULT IN NO FIRE WEATHER CONCERNS THROUGH THE END
OF THE WEEK. WARMER AND DRIER CONDITIONS WILL RETURN EARLY NEXT
WEEK.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...CLAYCOMB
SHORT TERM...TJT
LONG TERM...RE
AVIATION...RUBIN
FIRE WEATHER...TJT
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1027 PM MDT TUE MAY 28 2013
.UPDATE...
ISSUED AT 1008 PM MDT TUE MAY 28 2013
WENT AHEAD AND LET THE SEVERE THUNDERSTORM WATCH EXPIRE ON TIME AT
10 PM THIS EVENING FOR THE PANHANDLE. THERE ARE STILL SOME
THUNDERSTORMS OVER THE SOUTHERN PANHANDLE COMING IN FROM NORTHEAST
COLORADO...BUT THE ATMOSPHERE HAS BEEN WORKED OVER BY NUMEROUS
THUNDERSTORMS...SO DO NOT EXPECT STORMS TO BECOME SEVERE AGAIN.
WILL NEED TO WATCH EASTERN LARAMIE COUNTY LATE THIS EVENING AS
STORMS MOVE NORTH OUT OF COLORADO. LATEST RUC CAPE HAS AROUND 600
J/KG WITH CLOSE TO 900 J/KG UP NEAR BORDEAUX. KEPT THE RELATIVELY
HIGH POPS...40 PERCENT OR SO...FOR THE OVERNIGHT HOURS.
FRONT/DRYLINE PUSHES EAST INTO CENTRAL NEBRASKA BY LATE MORNING.
SEVERE THUNDERSTORMS SHOULD BE WELL EAST OF THE FORECAST AREA FOR
WEDNESDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY EVENING) ISSUED AT
247 PM MDT TUE MAY 28 2013
CURRENT KCYS RADAR LOOP SHOWS THUNDERSTORMS JUST STARTING TO
DEVELOP ACROSS THE HIGH PLAINS OF SOUTHEAST WYOMING AND INTO
WESTERN NEBRASKA. THERE IS STILL A SLIGHT CHANCE OF SEVERE
THUNDERSTORMS LATE THIS AFTERNOON THROUGH TONIGHT...BUT WITH HIGH
LEVEL CLOUDS PUSHING ACROSS THE EASTERN PLAINS FROM THIS
MORNING...CHANCES ARE A LITTLE LESS THAN EARLIER ANTICIPATED.
COVERAGE OF SHOWERS AND THUNDERSTORMS WILL INCREASE THROUGH THIS
AFTERNOON WITH SOME MODERATE TO HIGH RAINFALL AMOUNTS POSSIBLE
OVER FAR EASTERN WYOMING AND WESTERN NEBRASKA...WHERE LOCAL
AMOUNTS MAY BE AROUND 1 INCH. MAIN THREATS FROM THESE
THUNDERSTORMS WILL BE HAIL...GUSTY WINDS...AND FREQUENT LIGHTNING.
OFF AND ON SHOWERS AND TSTORMS WILL CONTINUE THROUGH TONIGHT ACROSS
THE HIGH PLAINS WITH THE BEST CHANCE ACROSS WESTERN NEBRASKA. THIS
ACTIVITY WILL BE ASSOCIATED WITH THE TROUGH AXIS BEGINNING TO PUSH
ACROSS THE ROCKIES TONIGHT AS IT BECOMES NEGATIVELY TILTED.
THUNDERSTORM POTENTIAL WILL BE LESS ON WEDNESDAY AS COOLER AIR
MOVES INTO THE AREA...ALTHOUGH LOCATIONS EAST OF THE
NEBRASKA/WYOMING BORDER HAVE THE BEST POTENTIAL TO SEE STRONG OR
SEVERE STORMS AS THE TROUGH AXIS WILL BE RIGHT OVER SOUTHEAST
WYOMING WEDNESDAY AFTERNOON. FORECAST FOR SOUTHEAST WYOMING WILL
BE TRICKY WITH THE TROUGH AXIS OVERHEAD AND DOWNSLOPE WINDS JUST
BEHIND THE TROUGH. THE NAM AND GEM SHOW RAIN SHOWERS AND EMBEDDED
THUNDER ACROSS SOUTHEAST WYOMING WITH SOME PRETTY GOOD QPF AMOUNTS
WHILE THE GFS AND ECMWF ARE ON THE DRY SIDE WITH LOW DEWPOINTS.
KEPT THE HIGHEST POP FROM NIOBRARA COUNTY SOUTHEAST INTO THE
NORTHERN PANHANDLE OF NEBRASKA. BELIEVE IT WILL BE TOUGH TO AVOID
CONVECTIVE ACTIVITY EVEN ACROSS SOUTHEAST WYOMING...SO INCREASED
POP BETWEEN 30 TO 60 PERCENT ALONG I25 AND I80 AS WELL.
PRECIPITATION WILL PUSH NORTH AS THE TROUGH BECOMES A CLOSED LOW
NORTHEAST OF THE FORECAST AREA OVER THE DAKOTAS. EXPECT DRIER AIR
TO PUSH INTO THE SOUTHERN HALF OF THE FORECAST AREA ALONG I80
WEDNESDAY NIGHT AND THURSDAY. INCREASED TEMPERATURES ON THURSDAY
AND BELIEVE IT WILL BE A LITTLE BIT WARMER COMPARED TO WEDNESDAY
DUE TO DOWNSLOPE WINDS AND ADIABATIC WARMING. TEMPERATURES WILL BE
IN THE 60S TO LOW 70S OVER MOST OF THE AREA WITH PERHAPS MID TO
UPPER 50S ACROSS THE HIGH VALLEYS WEST OF THE LARAMIE RANGE.
.LONG TERM...(FRIDAY THROUGH TUESDAY) ISSUED AT 220 PM MDT TUE
MAY 28 2013
WINDY AND A LITTLE COOLER CONDITIONS FOR FRIDAY AS SFC/UPPER LOW
MOVE SLOWLY EAST OVER THE DAKOTAS. MAIN DIFFICULTY WILL BE HOW MUCH
WRAP AROUND SHOWERS PROGRESS SOUTH INTO THE CWA. BEST CHANCES OVER
THE NORTH AND HAVE TAILORED POPS THIS WAY. NEXT PUSH OF COOLER AIR
WILL SINK OVER THE AREA LATE FRIDAY COOLING THINGS A LITTLE MORE
FOR SATURDAY ALONG WITH WIDELY SCATTERED SHOWERS...POSSIBLY A
LITTLE MORE WIDESPREAD. DRY AND WARMER CONDITIONS RETURN SUNDAY
AND MONDAY AS A SHORT UPPER RIDGE MOVES BY. UPPER TROF THEN
SETTLES OVER THE PACIFIC NW EARLY NEXT WEEK WITH SW FLOW ALOFT
BECOMING ESTABLISHED OVER THE CWA BY LATE MONDAY. CHANCES FOR
WIDELY SCTD SHOWERS AND TSTRMS INCREASE A BIT TUESDAY AS MOISTURE
AND INSTABILITY INCREASE.
&&
.AVIATION...(FOR THE 00Z TAF ISSUANCE)
SCATTERED TO NUMEROUS THUNDERSTORMS OVER THE WESTERN NEBRASKA
PANHANDLE WILL CONTINUE EARLY THIS EVENING. BRIEF MVFR VIS AND CIGS
ARE POSSIBLE IN THESE THUNDERSTORMS WITH FREQUENT
LIGHTNING...HAIL...AND GUSTY WINDS UP TO 50 MPH. ACTIVITY WILL
GRADUALLY DIMINISH AND PUSH EAST OF KSNY TO KCDR AFTER 04Z LATE THIS
EVENING. ISOLATED SHOWERS AND TSTORMS ARE EXPECTED ACROSS SOUTHEAST
WYOMING WHERE IT IS SIGNIFICANTLY DRIER...VFR CONDITIONS WILL
CONTINUE THROUGH TONIGHT FROM KRWL...TO KCYS.
THERE IS HIGHER CONFIDENCE THAT PATCHY FOG AND LOW CIGS WILL DEVELOP
AGAIN ACROSS WESTERN NEBRASKA...ESPECIALLY AT KSNY AND KAIA. ADDED
IFR CONDITIONS TO THE 00Z TAF AFTER MIDNIGHT.
&&
.FIRE WEATHER...
ISSUED AT 155 PM MDT TUE MAY 28 2013
CHANCES FOR MORE WIDESPREAD RAINFALL AND WETTING RAINS WILL
INCREASE DURING THE NEXT 12 TO 48 HOURS AS A PACIFIC STORM SYSTEM
MOVES ACROSS THE CENTRAL ROCKIES AND ADJACENT PLAINS. FUELS IN
GREEN UP STAGE...COOLER TEMPERATURES AND HIGHER RELATIVE
HUMIDITIES WILL RESULT IN NO FIRE WEATHER CONCERNS THROUGH THE END
OF THE WEEK. WARMER AND DRIER CONDITIONS WILL RETURN EARLY NEXT
WEEK.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...CLAYCOMB
SHORT TERM...TJT
LONG TERM...RE
AVIATION...TJT
FIRE WEATHER...TJT
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
449 AM PDT WED MAY 29 2013
...BECOMING MUCH HOTTER AND DRIER BY FRIDAY AND SATURDAY...
.DISCUSSION...AS OF 3:25 AM PDT WEDNESDAY...KMUX RADAR SHOWS THAT
ECHOS HAVE FINALLY EXITED OUR CWA TO THE EAST ALTHOUGH IN THE PAST
HOUR LIGHT RAIN WAS REPORTED IN SANTA ROSA. SO...STILL A FEW
POCKETS OF LOW ELEVATION RAIN. SATELLITE FOG PRODUCT INDICATES
POCKETS OF CLOUDS ACROSS MOST OF THE COAST AND INTO PART OF THE SF
BA REGION. RIGHT NOW FOG FORMATION DOES LOOK UNLIKELY. LOOK FOR
CLOUDS TO DISSIPATE THROUGH THE DAY WITH GENERALLY SUNNY
CONDITIONS BY AFTERNOON WITH HIGHS IN THE 60S AT THE COAST AND 70S
INLAND.
MAIN WEATHER STORY WILL BE THE RETURN OF MUCH WARMER WEATHER AS A
RIDGE OF HIGH PRESSURE BUILDS IN FROM THE PACIFIC WHILE THE FLOW
AT THE SURFACE BECOMES MOSTLY OFFSHORE. ALTHOUGH 850 MB HEIGHTS
AREN`T THAT IMPRESSIVE (JUST 584-586 DM) 850 TEMPS WILL WARM TO
AROUND 24 C AND WILL COMBINE WITH A FAVORABLE FLOW AT THE SURFACE
TO INCREASE HIGHS EACH DAY WITH THE WARMEST READINGS FORECAST FOR
SATURDAY. BY THAT DAY HIGHS WILL BE IN THE 70S AND 80S AT THE
COAST WITH 90S TO LOWER 100S FOR INLAND SPOTS.
LOOKING AT VARIOUS MODEL DATA PLUS THE HEART WARNING SYSTEM
INDICATES THAT A POSSIBILITY OF HEAT PRODUCTS BEING NEEDED ON
SATURDAY -- ESPECIALLY IF THE THERMAL TROUGH SET UP OFF THE COAST
AND HIGHS ARE ON THE UPPER RANGE OF GUIDANCE VALUES. IT IS STILL A
FEW DAYS OFF, SO WILL WAIT TO SEE WHAT THE NEWEST NUMBERS SHOW
OVER THE NEXT 36 HOURS. IMPORTANT TO NOTE THAT THE ANOMALY
INFORMATION SHOWS THIS EVENT WOULD BE AT MOST 2 STANDARD
DEVIATIONS ABOVE NORMAL FOR TEMPERATURES (AND JUST ABOUT 1 ABOVE
NORMAL FOR HEIGHTS) WHICH WOULD GIVE WEIGHT TO IT FALLING SHORT OF
RECORD BREAKING HEAT FOR MOST SPOTS.
ONSHORE FLOW WILL BEGIN TO RETURN ON SUNDAY AND MOVE BACK ACROSS
OUR AREA BY MONDAY. THIS WILL LEAD TO A RETURN TO MORE SEASONABLE
VALUES THROUGH AT LEAST NEXT WEDNESDAY -- 60S TO LOWER 70S AT THE
COAST WITH 70S AND 80S FOR INLAND SPOTS.
&&
.AVIATION...AS OF 4:40 AM PDT WEDNESDAY...POSSIBLE MVFR CIGS
THROUGH 18Z. LOW CONFIDENCE. MOST OF THE SHORT TERM MODELS KEEP
THE TERMINALS AT VFR...HOWEVER...THE HRRR AND CURRENT SATELLITE
TRENDS INDICATE STRATUS MAY IMPACT THE REGION THROUGH AT LEAST
18Z. OTHERWISE...MODERATE ONSHORE FLOW THIS AFTERNOON WITH LIKELY
RETURN OF MVFR AND POSSIBLE IFR CIGS AROUND MIDNIGHT.
VICINITY OF KSFO...POSSIBLE MVFR CIGS THROUGH THE EARLY MORNING
HOURS. VERY LOW CONFIDENCE. MODERATE ONSHORE FLOW THIS
AFTERNOON...WITH WESTERLY WIND GUSTS TO 25 KT.
KSFO BRIDGE APPROACH...THE APPROACH MAY BE IMPACTED BY PATCHY
STRATUS AN HOUR LATER THAN THE TERMINAL.
MONTEREY BAY AREA TERMINALS...MVFR CIGS THROUGH 19Z...LOW CONFIDENCE.
STRATUS LOOKS TO BE FILLING IN QUICKLY AND IS FORECAST TO PERSIST
THROUGH THE LATE MORNING HOURS. MODERATE ONSHORE FLOW THIS
AFTERNOON WITH A RETURN OF STRATUS JUST BEFORE MIDNIGHT.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...SCA...SF BAY FROM 2 PM
SCA...MRY BAY FROM 2 PM
SCA...PIGEON PT TO PT PINOS 0-10 NM FROM 2 PM
SCA...PT ARENA TO PT REYES 0-10 NM FROM 2 PM
SCA...PT REYES TO PIGEON PT 0-10 NM FROM 2 PM
SCA...PT ARENA TO PIGEON PT 10-60 NM FROM 2 PM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM FROM 2 PM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
&&
$$
PUBLIC FORECAST: BELL
AVIATION/MARINE: RILEY
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.SANFRANCISCOBAYAREA.GOV
WWW.TWITTER.COM/NWSBAYAREA
WWW.YOUTUBE.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS ALBANY NY
1006 AM EDT WED MAY 29 2013
.SYNOPSIS...
SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A WARM FRONT
WILL MOVE THROUGH THE REGION THIS MORNING...ESPECIALLY FOR AREAS TO
THE NORTH OF INTERSTATE 90. AS AN UPPER LEVEL DISTURBANCE MOVES
CLOSE TO THE REGION...SOME STRONG THUNDERSTORMS ARE POSSIBLE THIS
AFTERNOON THROUGH THIS EVENING. MUCH WARMER TEMPERATURES AND MUGGY
CONDITIONS ARE EXPECTED FOR THE REMAINDER OF THE WEEK...WITH SOME
ADDITIONAL THUNDERSTORMS POSSIBLE OVER THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
SEVERE THUNDERSTORMS POSSIBLE THIS AFTERNOON INTO THIS
EVENING...
AS OF 1000 AM EDT...BANDS OF SHOWERS AND FEW EMBEDDED RUMBLES OF
THUNDER ARE MOVING ACROSS THE FA. RAINFALL WILL BE LIGHT TO
MODERATE IN INTENSITY. IN THE WAKE OF THESE SHOWERS EXPECT SOME
CLEARING TO DEVELOP WHICH IS ALREADY NOTED ON THE VISIBLE SAT PICS
ACRS PTNS OF WRN AND CNTRL NY. TEMPS THIS MORNING WERE GENERALLY
IN THE 60S
BY LATE THIS MORNING...THE WARM FRONT WILL BE LIFTING NORTH
ACROSS OUR NORTHERN ZONES. THERE STILL MAY BE SOME SHOWERS WITH
THE FRONT ACROSS OUR NORTHERN AREAS...OTHERWISE...THERE WILL BE A
LULL IN THE ACTIVITY ACROSS MUCH OF THE REMAINDER OF THE AREA.
SOME BREAKS OF SUN MAY START TO DEVELOP...ESP FOR VALLEY AREAS
FROM THE CAPITAL REGION ON SOUTH. THE CANADIAN CLOUD MODEL SHOWS
SOME BREAKS STARTING TO DEVELOP BY AROUND 16Z FOR THE HUDSON
VALLEY REGION. WITH A LIGHT S-SW WIND IN PLACE...DEWPOINTS WILL
CONTINUE TO RISE INTO THE LOWER TO MID 60S F.
BY AFTERNOON...A SHORTWAVE TROUGH WILL BE MOVING ACROSS THE TOP OF
DEVELOPING RIDGE ACROSS THE EASTERN CONUS...MOVING FROM THE GREAT
LAKES AND LOWER ONTARIO INTO UPSTATE NY. THIS SHORTWAVE...AIDED BY
A STRONG 30-40 KTS LOW LEVEL JET AT 850 HPA WILL HELP FIRE
CONVECTION IN THE WARM SECTOR.
THE NAM12...LOCAL HIRES WRF AND 3KM HRRR ALL SHOW
CONVECTION DEVELOPING ACROSS WESTERN AND CENTRAL NY DURING THE
EARLY AFTN. THIS ACTIVITY WILL SPREAD INTO OUR AREA FOR THE MID
AFTN THROUGH THE EVENING HOURS.
THERE ARE SEVERAL FACTORS WHICH POINT TO THE POTENTIAL FOR SEVERE
THUNDERSTORMS. BECAUSE OF THE STRENGTH OF THE LLJ...0-6 KM BULK SHEAR
WITH BE AROUND 30-40 KTS. 0-3 KM HELICITY VALUES ARE EXPECTED TO
BE AROUND 200 M2/S2 AND 0-1 KM HELICITY VALUES ARE ALSO VERY
IMPRESSIVE...WITH 100-200 M2/S2 BY EVENING. WHILE MID LEVEL LAPSE
RATES AREN/T OVERLY STRONG...VALUES OF 6-6.5 DEGREES C/KM WILL BE
SUFFICIENT FOR PRODUCING UPDRAFTS CAPABLE OF SEVERE WIND/HAIL.
WHILE THE MAIN THREAT WILL BE DAMAGING WINDS...THE IMPRESSIVE
HELICITY VALUES AND THE FACT THAT THIS SAME SYSTEM PRODUCED
TORNADOES LAST EVENING JUST UPSTREAM ACROSS LOWER MICHIGAN WOULD
POINT TO THE POTENTIAL FOR AN ISOLATED TORNADO OR TWO. THE
NAM12/GFS/AND ECMWF ALL DID SHOW SIGNIFICANT TORNADO PARAMETERS IN
EXCESS OF 1 AT SOME LOCATION IN OUR AREA...SO THE TORNADIC
POTENTIAL SHOULD NOT BE IGNORED. SPC AGREES WITH THIS ASSESSMENT
AND HAS OUR AREA IN A SLIGHT RISK...WITH A 5% PROBABILITY FOR A
TORNADO WITHIN 25 MI OF ANY PARTICULAR LOCATION.
THE MAIN INHIBITING FACTOR WILL BE HAVING ENOUGH INSTABILITY.
THERE ARE PLENTY OF CLOUDS AROUND...EVEN UPSTREAM IN THE WARM
SECTOR WITH LINGERING DEBRIS CLOUDS. IF ENOUGH INSTABILITY ISN/T
REALIZED...STORMS MAY HAVE A DIFFICULT TIME GROWING VERY
TALL...AND THE SEVERE POTENTIAL WOULD BE MINIMIZED. AT THIS
POINT...ALL MODELS SHOW CAPE VALUES OF 1000-1500 J/KG...BUT THE
POTENTIAL FOR SUFFICIENT SURFACE BASED CAPE WILL HAVE TO BE
MONITORED THROUGH THE MORNING HOURS.
MAX TEMPS WILL RANGE FROM THE MID 70S TO LOW 80S. IF MORE CLEARING
OCCURS...MAX TEMPS COULD WIND UP ON THE WARMER END OF THIS
RANGE...ESP FROM THE CAPITAL REGION ON SOUTH.
WITH THE LOSS OF HEATING...AND WITH THE SHORTWAVE MOVING TO THE
EAST OF THE AREA...THUNDERSTORM POTENTIAL WILL DIMINISH BY LATE
THIS EVENING. IT SHOULD CLEAR OUT...ALTHOUGH THERE WILL BE
POTENTIAL FOR PATCHY FOG IN THOSE AREAS THAT RECEIVE RAINFALL. MIN
TEMPS WILL BE IN THE 50S TO LOW 60S.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
WARM AND MUGGY WEATHER IS EXPECTED FOR THE SHORT TERM PERIOD AS
OUR REGION WILL BE DOMINATED BY A STRONG RIDGE AT 500 HPA CENTERED
OVER THE MID ATLANTIC REGION. 850 HPA TEMPS WILL SURGE TO 16-18
DEGREES C...SO MAX TEMPS WILL REACH THE UPPER 80S TO LOW 90S FOR
BOTH THURSDAY AND FRIDAY. OVERNIGHT LOWS WILL BE WARM AND
STICKY...WITH MAINLY UPPER 50S TO MID 60S AT NIGHT.
WHILE IT SHOULD BE WARM ENOUGH ALOFT TO KEEP A CAP ON ANY
CONVECTION...WE WILL GO WITH A SLIGHT CHC FOR A SHOWER OR
THUNDERSTORM ON THURSDAY AFTN IN CASE ANYTHING IS ABLE TO DEVELOP.
FRIDAY LOOKS EVEN MORE CAPPED...SO WE WILL KEEP THE FORECAST
COMPLETELY DRY FOR FRIDAY WITH A MOSTLY SUNNY TO PARTLY SUNNY SKY.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
HEAT CONTINUES INTO THE FIRST PART OF THE WEEKEND WITH HIGHS
SATURDAY WELL IN THE 80S TO NEAR 90. COLD FRONT AND AMPLIFYING
NORTHERN STREAM UPPER ENERGY APPROACH SUNDAY...TRACKING THROUGH OUR
REGION THE BEGINNING OF THE WEEK...WITH EXACT TIMING TO BE
DETERMINED. SINCE THE EXACT TIMING IS UNKNOWN...INCREASING CHANCES
FOR SHOWERS AND THUNDERSTORMS SUNDAY AND SUNDAY NIGHT...BUILDING
INTO THE MID HUDSON VALLEY AND WESTERN NEW ENGLAND LATER SUNDAY
NIGHT AND MONDAY. DRYING AND COOLING EXPECTED ONCE THE FRONT
EXITS...MONDAY NIGHT AND TUESDAY.
SOME STRONG THUNDERSTORMS ARE POSSIBLE SUNDAY AFTERNOON THROUGH
MONDAY AFTERNOON..DEPENDING ON THE EXACT TIMING OF THE FRONT. THERE
IS A DECENT CONSENSUS FOR A NOTICEABLE COOL DOWN AFTER THE FRONTAL
PASSAGE. HIGHS SUNDAY IN THE UPPER 70S TO MID 80S...COOLING TO HIGHS
IN THE UPPER 60S TO MID 70S MONDAY AND MID 60S TO LOWER 70S TUESDAY.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
ANOTHER AREA OF SHOWERS ASSOCIATED WITH AN OLD WEAKENING CONVECTIVE
COMPLEX SHOULD TRACK THROUGH THE REGION THROUGH ABOUT 16Z...REDUCING
CEILINGS AND VISIBILITIES TO PERIODS OF MVFR AND IFR. IFR
CONDITIONS SHOULD DOMINATE AT KPOU AND KPSF WITH MVFR AT KALB AND
KGFL...BUT ALL SITES SHOULD HAVE PERIODS OF MVFR AND IFR.
ONCE THIS AREA OF SHOWERS EXITS AROUND 16Z...CEILINGS AND
VISIBILITIES SHOULD BE MAINLY VFR...THROUGH THE AFTERNOON AND IN TO
THE EVENING AS A WARM FRONT TRACKS THROUGH THE REGION. HOWEVER...
THERE ARE INDICATIONS THAT SOME ORGANIZED THUNDERSTORM ACTIVITY
COULD TRACK THROUGH THE REGION DURING THE LATE AFTERNOON. KEEPING
THE PROB30 INDICATIONS FOR THUNDERSTORMS BECAUSE THERE ARE ABOVE
NORMAL CHANCES FOR THUNDERSTORMS...ALTHOUGH SCATTERED...STILL ABOVE
NORMAL CHANCES. INDICATING MVFR CEILINGS AND VISIBILITIES IN
THUNDERSTORMS FOR NOW...BUT THERE COULD BE IFR FOR BRIEF PERIODS IN
ANY THUNDERSTORMS.
THE ORGANIZED THUNDERSTORM ACTIVITY COULD MOVE OUT DURING THE EARLY
EVENING...SO JUST INDICATING VCSH AFTER 00Z...WITH VFR CONDITIONS AS
THE WARM FRONT SHOULD BE EXITING AND THE WARM SECTOR EXPANDS OVER
THE REGION.
VARIABLE MAINLY SOUTHEAST TO SOUTHWEST WINDS AT LESS THAN 10 KT
THROUGH THE EARLY MORNING...BECOMING SOUTH TO SOUTHWEST AROUND 10 KT
AFTER 16Z...THEN TRENDING MORE SOUTHWEST AT LESS THAN 10 KT BY THIS
EVENING. A STEADY LIGHT WIND THIS EVENING MAY PREVENT ANY FOG FROM
FORMING AFTER ANY THUNDERSTORM ACTIVITY EXITS...BUT TOO EARLY TO
TELL WHEN STORMS WILL EXIT AND HOW MUCH WIND THERE WILL BE ONCE WE
BREAK INTO THE WARM SECTOR.
OUTLOOK...
THU-SUN...VFR/MVFR. CHC PM -TSRA EACH DAY. LATE NIGHT AND/OR
EARLY MORNING MVFR/IFR ASSOC WITH FOG POSSIBLE.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS OVER THE NEXT SEVERAL DAYS. A WETTING
RAINFALL OCCURRED IN MOST AREAS EARLY THIS MORNING AND ADDITIONAL
SHOWERS AND THUNDERSTORMS ARE POSSIBLE TODAY INTO THIS EVENING.
RH VALUES WILL ONLY DROP TO 55 TO 70 PERCENT TODAY. S-SW WINDS AT
5-15 MPH ARE EXPECTED TODAY.
W-SW WINDS WILL BE AROUND 5-10 MPH TONIGHT WITH RH VALUES RECOVERING TO
NEAR 100 PERCENT. AN ISOLATED SHOWER OR THUNDERSTORM IS POSSIBLE
TOMORROW WITH RH VALUES DROPPING 40 TO 55 PERCENT TOMORROW AFTERNOON.
&&
.HYDROLOGY...
NO WIDESPREAD HYDROLOGIC CONCERNS OVER THE NEXT FIVE DAYS ACROSS
THE HSA.
SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS THE REGION TODAY. PWAT
VALUES WILL BE ABOVE NORMAL...WITH VALUES UP TO 1.75 INCHES...SO
ANY SHOWER OR THUNDERSTORM IS CAPABLE OF PRODUCING TORRENTIAL
DOWNPOURS. ALTHOUGH WIDESPREAD RIVER FLOODING IS NOT
EXPECTED...SMALL STREAM...POOR DRAINAGE...OR URBAN FLOODING WILL
BE POSSIBLE DEPENDING ON THE EXACT TRACK OF SHOWERS AND
THUNDERSTORMS...ESPECIALLY IF SEVERAL THUNDERSTORMS TRACK OVER THE
SAME LOCATION. 3 HR FFG FROM THE NERFC IS AROUND 2-3 INCHES.
ISOLATED SHOWERS OR THUNDERSTORMS ARE POSSIBLE ON THURSDAY
AFTERNOON. OTHERWISE...IT WILL BE FAIRLY DRY THROUGH THE END OF
THE WORK WEEK. ADDITIONAL SHOWERS OR THUNDERSTORMS ARE POSSIBLE
OVER THE WEEKEND.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS/11
SHORT TERM...FRUGIS
LONG TERM...NAS
AVIATION...NAS
FIRE WEATHER...FRUGIS
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS ALBANY NY
729 AM EDT WED MAY 29 2013
.SYNOPSIS...
SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A WARM FRONT
WILL MOVE THROUGH THE REGION THIS MORNING...ESPECIALLY FOR AREAS TO
THE NORTH OF INTERSTATE 90. AS AN UPPER LEVEL DISTURBANCE MOVES
CLOSE TO THE REGION...SOME STRONG THUNDERSTORMS ARE POSSIBLE THIS
AFTERNOON THROUGH THIS EVENING. MUCH WARMER TEMPERATURES AND MUGGY
CONDITIONS ARE EXPECTED FOR THE REMAINDER OF THE WEEK...WITH SOME
ADDITIONAL THUNDERSTORMS POSSIBLE OVER THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
SEVERE THUNDERSTORMS POSSIBLE THIS AFTERNOON INTO THIS
EVENING...
AS OF 627 AM EDT...A WARM FRONT WAS SITUATED JUST SOUTH OF THE
REGION ACROSS THE CENTRAL PA AND NJ. AHEAD OF THIS WARM
FRONT...ISENTROPIC LIFT/WARM AIR ADVECTION IS ALLOWING FOR BANDS
OF SHOWERS AND ISOLD THUNDERSTORMS ACROSS WESTERN AND CENTRAL NEW
YORK. OVER THE NEXT FEW HOURS...THESE SHOWERS AND EMBEDDED RUMBLES
OF THUNDER WILL MOVE ACROSS OUR AREA...MAINLY THE CENTRAL AND
NORTHERN ZONES. RAINFALL WILL BE LIGHT TO MODERATE IN INTENSITY.
BY THE MID TO LATE MORNING HOURS...THE WARM FRONT WILL BE LIFTING
NORTH ACROSS OUR NORTHERN ZONES. THERE STILL MAY BE SOME SHOWERS
WITH THE FRONT ACROSS OUR NORTHERN AREAS...OTHERWISE...THERE WILL
BE A LULL IN THE ACTIVITY ACROSS MUCH OF THE REMAINDER OF THE
AREA. SOME BREAKS OF SUN MAY START TO DEVELOP...ESP FOR VALLEY
AREAS FROM THE CAPITAL REGION ON SOUTH. THE CANADIAN CLOUD MODEL
SHOWS SOME BREAKS STARTING TO DEVELOP BY AROUND 16Z FOR THE HUDSON
VALLEY REGION. WITH A LIGHT S-SW WIND IN PLACE...DEWPOINTS WILL
CONTINUE TO RISE INTO THE LOWER TO MID 60S F.
BY AFTERNOON...A SHORTWAVE TROUGH WILL BE MOVING ACROSS THE TOP OF
DEVELOPING RIDGE ACROSS THE EASTERN CONUS...MOVING FROM THE GREAT
LAKES AND LOWER ONTARIO INTO UPSTATE NY. THIS SHORTWAVE...AIDED BY
A STRONG 30-40 KTS LOW LEVEL JET AT 850 HPA WILL HELP FIRE
CONVECTION IN THE WARM SECTOR.
THE NAM12...LOCAL HIRES WRF AND 3KM HRRR ALL SHOW
CONVECTION DEVELOPING ACROSS WESTERN AND CENTRAL NY DURING THE
EARLY AFTN. THIS ACTIVITY WILL SPREAD INTO OUR AREA FOR THE MID
AFTN THROUGH THE EVENING HOURS.
THERE ARE SEVERAL FACTORS WHICH POINT TO THE POTENTIAL FOR SEVERE
THUNDERSTORMS. BECAUSE OF THE STRENGTH OF THE LLJ...0-6 KM BULK SHEAR
WITH BE AROUND 30-40 KTS. 0-3 KM HELICITY VALUES ARE EXPECTED TO
BE AROUND 200 M2/S2 AND 0-1 KM HELICITY VALUES ARE ALSO VERY
IMPRESSIVE...WITH 100-200 M2/S2 BY EVENING. WHILE MID LEVEL LAPSE
RATES AREN/T OVERLY STRONG...VALUES OF 6-6.5 DEGREES C/KM WILL BE
SUFFICIENT FOR PRODUCING UPDRAFTS CAPABLE OF SEVERE WIND/HAIL.
WHILE THE MAIN THREAT WILL BE DAMAGING WINDS...THE IMPRESSIVE
HELICITY VALUES AND THE FACT THAT THIS SAME SYSTEM PRODUCED
TORNADOES LAST EVENING JUST UPSTREAM ACROSS LOWER MICHIGAN WOULD
POINT TO THE POTENTIAL FOR AN ISOLATED TORNADO OR TWO. THE
NAM12/GFS/AND ECMWF ALL DID SHOW SIGNIFICANT TORNADO PARAMETERS IN
EXCESS OF 1 AT SOME LOCATION IN OUR AREA...SO THE TORNADIC
POTENTIAL SHOULD NOT BE IGNORED. SPC AGREES WITH THIS ASSESSMENT
AND HAS OUR AREA IN A SLIGHT RISK...WITH A 5% PROBABILITY FOR A
TORNADO WITHIN 25 MI OF ANY PARTICULAR LOCATION.
THE MAIN INHIBITING FACTOR WILL BE HAVING ENOUGH INSTABILITY.
THERE ARE PLENTY OF CLOUDS AROUND...EVEN UPSTREAM IN THE WARM
SECTOR WITH LINGERING DEBRIS CLOUDS. IF ENOUGH INSTABILITY ISN/T
REALIZED...STORMS MAY HAVE A DIFFICULT TIME GROWING VERY
TALL...AND THE SEVERE POTENTIAL WOULD BE MINIMIZED. AT THIS
POINT...ALL MODELS SHOW CAPE VALUES OF 1000-1500 J/KG...BUT THE
POTENTIAL FOR SUFFICIENT SURFACE BASED CAPE WILL HAVE TO BE
MONITORED THROUGH THE MORNING HOURS.
MAX TEMPS WILL RANGE FROM THE MID 70S TO LOW 80S. IF MORE CLEARING
OCCURS...MAX TEMPS COULD WIND UP ON THE WARMER END OF THIS
RANGE...ESP FROM THE CAPITAL REGION ON SOUTH.
WITH THE LOSS OF HEATING...AND WITH THE SHORTWAVE MOVING TO THE
EAST OF THE AREA...THUNDERSTORM POTENTIAL WILL DIMINISH BY LATE
THIS EVENING. IT SHOULD CLEAR OUT...ALTHOUGH THERE WILL BE
POTENTIAL FOR PATCHY FOG IN THOSE AREAS THAT RECEIVE RAINFALL. MIN
TEMPS WILL BE IN THE 50S TO LOW 60S.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
WARM AND MUGGY WEATHER IS EXPECTED FOR THE SHORT TERM PERIOD AS
OUR REGION WILL BE DOMINATED BY A STRONG RIDGE AT 500 HPA CENTERED
OVER THE MID ATLANTIC REGION. 850 HPA TEMPS WILL SURGE TO 16-18
DEGREES C...SO MAX TEMPS WILL REACH THE UPPER 80S TO LOW 90S FOR
BOTH THURSDAY AND FRIDAY. OVERNIGHT LOWS WILL BE WARM AND
STICKY...WITH MAINLY UPPER 50S TO MID 60S AT NIGHT.
WHILE IT SHOULD BE WARM ENOUGH ALOFT TO KEEP A CAP ON ANY
CONVECTION...WE WILL GO WITH A SLIGHT CHC FOR A SHOWER OR
THUNDERSTORM ON THURSDAY AFTN IN CASE ANYTHING IS ABLE TO DEVELOP.
FRIDAY LOOKS EVEN MORE CAPPED...SO WE WILL KEEP THE FORECAST
COMPLETELY DRY FOR FRIDAY WITH A MOSTLY SUNNY TO PARTLY SUNNY SKY.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
HEAT CONTINUES INTO THE FIRST PART OF THE WEEKEND WITH HIGHS
SATURDAY WELL IN THE 80S TO NEAR 90. COLD FRONT AND AMPLIFYING
NORTHERN STREAM UPPER ENERGY APPROACH SUNDAY...TRACKING THROUGH OUR
REGION THE BEGINNING OF THE WEEK...WITH EXACT TIMING TO BE
DETERMINED. SINCE THE EXACT TIMING IS UNKNOWN...INCREASING CHANCES
FOR SHOWERS AND THUNDERSTORMS SUNDAY AND SUNDAY NIGHT...BUILDING
INTO THE MID HUDSON VALLEY AND WESTERN NEW ENGLAND LATER SUNDAY
NIGHT AND MONDAY. DRYING AND COOLING EXPECTED ONCE THE FRONT
EXITS...MONDAY NIGHT AND TUESDAY.
SOME STRONG THUNDERSTORMS ARE POSSIBLE SUNDAY AFTERNOON THROUGH
MONDAY AFTERNOON..DEPENDING ON THE EXACT TIMING OF THE FRONT. THERE
IS A DECENT CONSENSUS FOR A NOTICEABLE COOL DOWN AFTER THE FRONTAL
PASSAGE. HIGHS SUNDAY IN THE UPPER 70S TO MID 80S...COOLING TO HIGHS
IN THE UPPER 60S TO MID 70S MONDAY AND MID 60S TO LOWER 70S TUESDAY.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
ANOTHER AREA OF SHOWERS ASSOCIATED WITH AN OLD WEAKENING CONVECTIVE
COMPLEX SHOULD TRACK THROUGH THE REGION THROUGH ABOUT 16Z...REDUCING
CEILINGS AND VISIBILITIES TO PERIODS OF MVFR AND IFR. IFR
CONDITIONS SHOULD DOMINATE AT KPOU AND KPSF WITH MVFR AT KALB AND
KGFL...BUT ALL SITES SHOULD HAVE PERIODS OF MVFR AND IFR.
ONCE THIS AREA OF SHOWERS EXITS AROUND 16Z...CEILINGS AND
VISIBILITIES SHOULD BE MAINLY VFR...THROUGH THE AFTERNOON AND IN TO
THE EVENING AS A WARM FRONT TRACKS THROUGH THE REGION. HOWEVER...
THERE ARE INDICATIONS THAT SOME ORGANIZED THUNDERSTORM ACTIVITY
COULD TRACK THROUGH THE REGION DURING THE LATE AFTERNOON. KEEPING
THE PROB30 INDICATIONS FOR THUNDERSTORMS BECAUSE THERE ARE ABOVE
NORMAL CHANCES FOR THUNDERSTORMS...ALTHOUGH SCATTERED...STILL ABOVE
NORMAL CHANCES. INDICATING MVFR CEILINGS AND VISIBILITIES IN
THUNDERSTORMS FOR NOW...BUT THERE COULD BE IFR FOR BRIEF PERIODS IN
ANY THUNDERSTORMS.
THE ORGANIZED THUNDERSTORM ACTIVITY COULD MOVE OUT DURING THE EARLY
EVENING...SO JUST INDICATING VCSH AFTER 00Z...WITH VFR CONDITIONS AS
THE WARM FRONT SHOULD BE EXITING AND THE WARM SECTOR EXPANDS OVER
THE REGION.
VARIABLE MAINLY SOUTHEAST TO SOUTHWEST WINDS AT LESS THAN 10 KT
THROUGH THE EARLY MORNING...BECOMING SOUTH TO SOUTHWEST AROUND 10 KT
AFTER 16Z...THEN TRENDING MORE SOUTHWEST AT LESS THAN 10 KT BY THIS
EVENING. A STEADY LIGHT WIND THIS EVENING MAY PREVENT ANY FOG FROM
FORMING AFTER ANY THUNDERSTORM ACTIVITY EXITS...BUT TOO EARLY TO
TELL WHEN STORMS WILL EXIT AND HOW MUCH WIND THERE WILL BE ONCE WE
BREAK INTO THE WARM SECTOR.
OUTLOOK...
THU-SUN...VFR/MVFR. CHC PM -TSRA EACH DAY. LATE NIGHT AND/OR
EARLY MORNING MVFR/IFR ASSOC WITH FOG POSSIBLE.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS OVER THE NEXT SEVERAL DAYS. A WETTING
RAINFALL OCCURRED IN MOST AREAS EARLY THIS MORNING AND ADDITIONAL
SHOWERS AND THUNDERSTORMS ARE POSSIBLE TODAY INTO THIS EVENING.
RH VALUES WILL ONLY DROP TO 55 TO 70 PERCENT TODAY. S-SW WINDS AT
5-15 MPH ARE EXPECTED TODAY.
W-SW WINDS WILL BE AROUND 5-10 MPH TONIGHT WITH RH VALUES RECOVERING TO
NEAR 100 PERCENT. AN ISOLATED SHOWER OR THUNDERSTORM IS POSSIBLE
TOMORROW WITH RH VALUES DROPPING 40 TO 55 PERCENT TOMORROW AFTERNOON.
&&
.HYDROLOGY...
NO WIDESPREAD HYDROLOGIC CONCERNS OVER THE NEXT FIVE DAYS ACROSS
THE HSA.
SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS THE REGION TODAY. PWAT
VALUES WILL BE ABOVE NORMAL...WITH VALUES UP TO 1.75 INCHES...SO
ANY SHOWER OR THUNDERSTORM IS CAPABLE OF PRODUCING TORRENTIAL
DOWNPOURS. ALTHOUGH WIDESPREAD RIVER FLOODING IS NOT
EXPECTED...SMALL STREAM...POOR DRAINAGE...OR URBAN FLOODING WILL
BE POSSIBLE DEPENDING ON THE EXACT TRACK OF SHOWERS AND
THUNDERSTORMS...ESPECIALLY IF SEVERAL THUNDERSTORMS TRACK OVER THE
SAME LOCATION. 3 HR FFG FROM THE NERFC IS AROUND 2-3 INCHES.
ISOLATED SHOWERS OR THUNDERSTORMS ARE POSSIBLE ON THURSDAY
AFTERNOON. OTHERWISE...IT WILL BE FAIRLY DRY THROUGH THE END OF
THE WORK WEEK. ADDITIONAL SHOWERS OR THUNDERSTORMS ARE POSSIBLE
OVER THE WEEKEND.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS
SHORT TERM...FRUGIS
LONG TERM...NAS
AVIATION...NAS
FIRE WEATHER...FRUGIS
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS ALBANY NY
627 AM EDT WED MAY 29 2013
.SYNOPSIS...
SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A WARM FRONT
WILL MOVE THROUGH THE REGION THIS MORNING...ESPECIALLY FOR AREAS TO
THE NORTH OF INTERSTATE 90. AS AN UPPER LEVEL DISTURBANCE MOVES
CLOSE TO THE REGION...SOME STRONG THUNDERSTORMS ARE POSSIBLE THIS
AFTERNOON THROUGH THIS EVENING. MUCH WARMER TEMPERATURES AND MUGGY
CONDITIONS ARE EXPECTED FOR THE REMAINDER OF THE WEEK...WITH SOME
ADDITIONAL THUNDERSTORMS POSSIBLE OVER THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
...SEVERE THUNDERSTORMS POSSIBLE THIS AFTERNOON INTO THIS
EVENING...
AS OF 627 AM EDT...A WARM FRONT WAS SITUATED JUST SOUTH OF THE
REGION ACROSS THE CENTRAL PA AND NJ. AHEAD OF THIS WARM
FRONT...ISENTROPIC LIFT/WARM AIR ADVECTION IS ALLOWING FOR BANDS
OF SHOWERS AND ISOLD THUNDERSTORMS ACROSS WESTERN AND CENTRAL NEW
YORK. OVER THE NEXT FEW HOURS...THESE SHOWERS AND EMBEDDED RUMBLES
OF THUNDER WILL MOVE ACROSS OUR AREA...MAINLY THE CENTRAL AND
NORTHERN ZONES. RAINFALL WILL BE LIGHT TO MODERATE IN INTENSITY.
BY THE MID TO LATE MORNING HOURS...THE WARM FRONT WILL BE LIFTING
NORTH ACROSS OUR NORTHERN ZONES. THERE STILL MAY BE SOME SHOWERS
WITH THE FRONT ACROSS OUR NORTHERN AREAS...OTHERWISE...THERE WILL
BE A LULL IN THE ACTIVITY ACROSS MUCH OF THE REMAINDER OF THE
AREA. SOME BREAKS OF SUN MAY START TO DEVELOP...ESP FOR VALLEY
AREAS FROM THE CAPITAL REGION ON SOUTH. THE CANADIAN CLOUD MODEL
SHOWS SOME BREAKS STARTING TO DEVELOP BY AROUND 16Z FOR THE HUDSON
VALLEY REGION. WITH A LIGHT S-SW WIND IN PLACE...DEWPOINTS WILL
CONTINUE TO RISE INTO THE LOWER TO MID 60S F.
BY AFTERNOON...A SHORTWAVE TROUGH WILL BE MOVING ACROSS THE TOP OF
DEVELOPING RIDGE ACROSS THE EASTERN CONUS...MOVING FROM THE GREAT
LAKES AND LOWER ONTARIO INTO UPSTATE NY. THIS SHORTWAVE...AIDED BY
A STRONG 30-40 KTS LOW LEVEL JET AT 850 HPA WILL HELP FIRE
CONVECTION IN THE WARM SECTOR.
THE NAM12...LOCAL HIRES WRF AND 3KM HRRR ALL SHOW
CONVECTION DEVELOPING ACROSS WESTERN AND CENTRAL NY DURING THE
EARLY AFTN. THIS ACTIVITY WILL SPREAD INTO OUR AREA FOR THE MID
AFTN THROUGH THE EVENING HOURS.
THERE ARE SEVERAL FACTORS WHICH POINT TO THE POTENTIAL FOR SEVERE
THUNDERSTORMS. BECAUSE OF THE STRENGTH OF THE LLJ...0-6 KM BULK SHEAR
WITH BE AROUND 30-40 KTS. 0-3 KM HELICITY VALUES ARE EXPECTED TO
BE AROUND 200 M2/S2 AND 0-1 KM HELICITY VALUES ARE ALSO VERY
IMPRESSIVE...WITH 100-200 M2/S2 BY EVENING. WHILE MID LEVEL LAPSE
RATES AREN/T OVERLY STRONG...VALUES OF 6-6.5 DEGREES C/KM WILL BE
SUFFICIENT FOR PRODUCING UPDRAFTS CAPABLE OF SEVERE WIND/HAIL.
WHILE THE MAIN THREAT WILL BE DAMAGING WINDS...THE IMPRESSIVE
HELICITY VALUES AND THE FACT THAT THIS SAME SYSTEM PRODUCED
TORNADOES LAST EVENING JUST UPSTREAM ACROSS LOWER MICHIGAN WOULD
POINT TO THE POTENTIAL FOR AN ISOLATED TORNADO OR TWO. THE
NAM12/GFS/AND ECMWF ALL DID SHOW SIGNIFICANT TORNADO PARAMETERS IN
EXCESS OF 1 AT SOME LOCATION IN OUR AREA...SO THE TORNADIC
POTENTIAL SHOULD NOT BE IGNORED. SPC AGREES WITH THIS ASSESSMENT
AND HAS OUR AREA IN A SLIGHT RISK...WITH A 5% PROBABILITY FOR A
TORNADO WITHIN 25 MI OF ANY PARTICULAR LOCATION.
THE MAIN INHIBITING FACTOR WILL BE HAVING ENOUGH INSTABILITY.
THERE ARE PLENTY OF CLOUDS AROUND...EVEN UPSTREAM IN THE WARM
SECTOR WITH LINGERING DEBRIS CLOUDS. IF ENOUGH INSTABILITY ISN/T
REALIZED...STORMS MAY HAVE A DIFFICULT TIME GROWING VERY
TALL...AND THE SEVERE POTENTIAL WOULD BE MINIMIZED. AT THIS
POINT...ALL MODELS SHOW CAPE VALUES OF 1000-1500 J/KG...BUT THE
POTENTIAL FOR SUFFICIENT SURFACE BASED CAPE WILL HAVE TO BE
MONITORED THROUGH THE MORNING HOURS.
MAX TEMPS WILL RANGE FROM THE MID 70S TO LOW 80S. IF MORE CLEARING
OCCURS...MAX TEMPS COULD WIND UP ON THE WARMER END OF THIS
RANGE...ESP FROM THE CAPITAL REGION ON SOUTH.
WITH THE LOSS OF HEATING...AND WITH THE SHORTWAVE MOVING TO THE
EAST OF THE AREA...THUNDERSTORM POTENTIAL WILL DIMINISH BY LATE
THIS EVENING. IT SHOULD CLEAR OUT...ALTHOUGH THERE WILL BE
POTENTIAL FOR PATCHY FOG IN THOSE AREAS THAT RECEIVE RAINFALL. MIN
TEMPS WILL BE IN THE 50S TO LOW 60S.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
WARM AND MUGGY WEATHER IS EXPECTED FOR THE SHORT TERM PERIOD AS
OUR REGION WILL BE DOMINATED BY A STRONG RIDGE AT 500 HPA CENTERED
OVER THE MID ATLANTIC REGION. 850 HPA TEMPS WILL SURGE TO 16-18
DEGREES C...SO MAX TEMPS WILL REACH THE UPPER 80S TO LOW 90S FOR
BOTH THURSDAY AND FRIDAY. OVERNIGHT LOWS WILL BE WARM AND
STICKY...WITH MAINLY UPPER 50S TO MID 60S AT NIGHT.
WHILE IT SHOULD BE WARM ENOUGH ALOFT TO KEEP A CAP ON ANY
CONVECTION...WE WILL GO WITH A SLIGHT CHC FOR A SHOWER OR
THUNDERSTORM ON THURSDAY AFTN IN CASE ANYTHING IS ABLE TO DEVELOP.
FRIDAY LOOKS EVEN MORE CAPPED...SO WE WILL KEEP THE FORECAST
COMPLETELY DRY FOR FRIDAY WITH A MOSTLY SUNNY TO PARTLY SUNNY SKY.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
HEAT CONTINUES INTO THE FIRST PART OF THE WEEKEND WITH HIGHS
SATURDAY WELL IN THE 80S TO NEAR 90. COLD FRONT AND AMPLIFYING
NORTHERN STREAM UPPER ENERGY APPROACH SUNDAY...TRACKING THROUGH OUR
REGION THE BEGINNING OF THE WEEK...WITH EXACT TIMING TO BE
DETERMINED. SINCE THE EXACT TIMING IS UNKNOWN...INCREASING CHANCES
FOR SHOWERS AND THUNDERSTORMS SUNDAY AND SUNDAY NIGHT...BUILDING
INTO THE MID HUDSON VALLEY AND WESTERN NEW ENGLAND LATER SUNDAY
NIGHT AND MONDAY. DRYING AND COOLING EXPECTED ONCE THE FRONT
EXITS...MONDAY NIGHT AND TUESDAY.
SOME STRONG THUNDERSTORMS ARE POSSIBLE SUNDAY AFTERNOON THROUGH
MONDAY AFTERNOON..DEPENDING ON THE EXACT TIMING OF THE FRONT. THERE
IS A DECENT CONSENSUS FOR A NOTICEABLE COOL DOWN AFTER THE FRONTAL
PASSAGE. HIGHS SUNDAY IN THE UPPER 70S TO MID 80S...COOLING TO HIGHS
IN THE UPPER 60S TO MID 70S MONDAY AND MID 60S TO LOWER 70S TUESDAY.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AN AREA OF SHOWERS ASSOCIATED WITH AN OLD WEAKENING CONVECTIVE
COMPLEX SHOULD TRACK THROUGH THE REGION THROUGH ABOUT 10Z...REDUCING
CEILINGS AND VISIBILITIES TO PERIODS OF MVFR AND IFR. IFR
CONDITIONS SHOULD DOMINATE AT KPOU AND KPSF WITH MVFR AT KALB AND
KGFL...BUT ALL SITES SHOULD HAVE PERIODS OF MVFR AND IFR.
ONCE THIS AREA OF SHOWERS EXITS...SOME LINGERING LOW CLOUDS IN THE
IFR/MVFR RANGE AND VISIBILITIES LIKELY IN THE MVFR RANGE...SHOULD
CONTINUE THROUGH ABOUT 14Z. CEILINGS AND VISIBILITIES SHOULD BE
MAINLY VFR AFTER 14Z...THROUGH THE AFTERNOON AND IN TO THE EVENING
AS A WARM FRONT TRACKS THROUGH THE REGION. HOWEVER...THERE ARE
INDICATIONS THAT SOME ORGANIZED THUNDERSTORM ACTIVITY COULD TRACK
THROUGH THE REGION DURING THE AFTERNOON. KEEPING THE PROB30
INDICATIONS FOR THUNDERSTORMS BECAUSE THERE ARE ABOVE NORMAL CHANCES
FOR THUNDERSTORMS...ALTHOUGH SCATTERED...STILL ABOVE NORMAL CHANCES.
INDICATING MVFR CEILINGS AND VISIBILITIES IN THUNDERSTORMS FOR
NOW...BUT THERE COULD BE IFR FOR BRIEF PERIODS IN ANY THUNDERSTORMS.
THE ORGANIZED THUNDERSTORM ACTIVITY COULD MOVE OUT DURING THE EARLY
EVENING...SO JUST INDICATING VCSH AFTER 23Z...WITH VFR CONDITIONS AS
THE WARM FRONT SHOULD BE EXITING AND THE WARM SECTOR EXPANDS OVER
THE REGION.
VARIABLE MAINLY SOUTHEAST TO SOUTHWEST WINDS AT LESS THAN 10 KT
THROUGH THE EARLY MORNING...BECOMING SOUTH TO SOUTHWEST AROUND 10 KT
AFTER 14Z...THEN TRENDING MORE SOUTHWEST AT LESS THAN 10 KT BY THIS
EVENING. A STEADY LIGHT WIND THIS EVENING MAY PREVENT ANY FOG FROM
FORMING AFTER ANY THUNDERSTORM ACTIVITY EXITS...BUT TOO EARLY TO
TELL WHEN STORMS WILL EXIT AND HOW MUCH WIND THERE WILL BE ONCE WE
BREAK INTO THE WARM SECTOR.
OUTLOOK...
THU-SUN...VFR/MVFR. CHC PM -TSRA EACH DAY. LATE NIGHT AND/OR
EARLY MORNING MVFR/IFR ASSOC WITH FOG POSSIBLE.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS OVER THE NEXT SEVERAL DAYS. A WETTING
RAINFALL OCCURRED IN MOST AREAS EARLY THIS MORNING AND ADDITIONAL
SHOWERS AND THUNDERSTORMS ARE POSSIBLE TODAY INTO THIS EVENING.
RH VALUES WILL ONLY DROP TO 55 TO 70 PERCENT TODAY. S-SW WINDS AT
5-15 MPH ARE EXPECTED TODAY.
W-SW WINDS WILL BE AROUND 5-10 MPH TONIGHT WITH RH VALUES RECOVERING TO
NEAR 100 PERCENT. AN ISOLATED SHOWER OR THUNDERSTORM IS POSSIBLE
TOMORROW WITH RH VALUES DROPPING 40 TO 55 PERCENT TOMORROW AFTERNOON.
&&
.HYDROLOGY...
NO WIDESPREAD HYDROLOGIC CONCERNS OVER THE NEXT FIVE DAYS ACROSS
THE HSA.
SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS THE REGION TODAY. PWAT
VALUES WILL BE ABOVE NORMAL...WITH VALUES UP TO 1.75 INCHES...SO
ANY SHOWER OR THUNDERSTORM IS CAPABLE OF PRODUCING TORRENTIAL
DOWNPOURS. ALTHOUGH WIDESPREAD RIVER FLOODING IS NOT
EXPECTED...SMALL STREAM...POOR DRAINAGE...OR URBAN FLOODING WILL
BE POSSIBLE DEPENDING ON THE EXACT TRACK OF SHOWERS AND
THUNDERSTORMS...ESPECIALLY IF SEVERAL THUNDERSTORMS TRACK OVER THE
SAME LOCATION. 3 HR FFG FROM THE NERFC IS AROUND 2-3 INCHES.
ISOLATED SHOWERS OR THUNDERSTORMS ARE POSSIBLE ON THURSDAY
AFTERNOON. OTHERWISE...IT WILL BE FAIRLY DRY THROUGH THE END OF
THE WORK WEEK. ADDITIONAL SHOWERS OR THUNDERSTORMS ARE POSSIBLE
OVER THE WEEKEND.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS
SHORT TERM...FRUGIS
LONG TERM...NAS
AVIATION...NAS
FIRE WEATHER...FRUGIS
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1129 AM EDT WED MAY 29 2013
.SYNOPSIS...
A WARM FRONT WILL CONTINUE TO LIFT NORTHWARD THROUGH TODAY AS AN
AREA OF HIGH PRESSURE OFF THE EASTERN SEABOARD SPREADS ITS INFLUENCE
INTO THE MID ATLANTIC REGION, BRINGING INCREASING HEAT AND HUMIDITY
TO THE AREA THROUGH THIS WEEKEND. FOR EARLY NEXT WEEK, A LOW
PRESSURE SYSTEM EMERGING FROM AROUND THE GREAT LAKES WILL SEND A
COLD FRONT THROUGH OUR REGION BY MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NEXT ESTF UPDATE CONTINUES TO BE HRRR BASED AS PER ITS BEST
HANDLING OF MESOSCALE MODELING OF ONGOING CONVECTION OR LACK
THEREOF. THIS BUMPS UP THE TIMING OF THE GREATEST THREAT IN OUR
FAR NRN CWA TO 21Z OR 22Z. ELSEWHERE WE MODIFIED THE ABERDEEN
SOUNDING AND THE CONVECTIVE TEMP (HIGH 80S) GETS REACHED LATE IN
THE AFTERNOON, SO AN ISOLATED THUNDERSTORM CAN NOT BE RULED OUT
FROM OCCURRING AND LOW POPS WERE MAINTAINED. MOST OF THE
CONVECTIVE STRENGTH PARAMETERS ARE IN THE MODERATE RANGE.
AS FAR AS SEVERE THREAT GOES, AS PREV FCSTR NOTED THAT FCST BULK
SHEAR VALUES ARE NOT VIGOROUS WITHIN OUR CWA, BUT ARE SUPPORTIVE
OF ORGANIZED CONVECTION JUST NORTH. WE HAVE TO WATCH FOR
INITIATION IN NORTHWEST PA THE NEXT HR OR TWO. THUS IF THERE IS
CHANCE OF SEVERE IT IS FROM THAT ONGOING CONVECTION BUILDING INTO
OUR CWA. ETA OF ARRIVAL DOES COINCIDE WELL FOR THUNDERSTORM
STRENGTH. ENHANCED WORDING KEPT UP NORTH.
NO BIG CHANGES WERE MADE TO ANTICIPATED MAX TEMPERATURES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
OTHER THAN TO MOVE THE CONVECTIVE PROCESS ALONG FASTER BY ABOUT AN
HOUR OR TWO, NO BIG CHANGES HERE.
THE LAST BAND OF WHATEVER HEAVY CONVECTION MOVES ESEWD FROM VCNTY
KRDG-KTTN AT AROUND 00-01Z AND WEAKENS JUST TO THE N OF KPNE AND
KACY AROUND 03Z. OTRW A WARM SUMMERLIKE NIGHT.
50 50 BLENDED 00Z/29 GFS/NAM GUIDANCE.
PATCHY FOG POSSIBLE LATE BUT PROBABLY NOTHING LIKE EARLY THIS
MORNING.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
TO START THE LONG TERM, SURFACE HIGH PRESSURE WILL BE FOUND OVER THE
CENTRAL ATLANTIC, EXTENDING ITS INFLUENCE WESTWARD INTO THE MIDDLE
ATLANTIC STATES. MEANWHILE, STRONG MID-LEVEL RIDGING WILL ALSO BE
TAKING HOLD ACROSS THE REGION. THIS LOOKS TO BE THE BEGINNING OF OUR
FIRST POTENTIAL HEAT WAVE OF THE SEASON, AS A STRENGTHENING
SOUTHWESTERLY FLOW THROUGH THE END OF THE WORK WEEK AND INTO THE
WEEKEND WILL BRING INCREASING HEAT AND HUMIDITY. MODEL 850MB AND
925MB TEMPS SUPPORT MAXIMUM TEMPERATURES EASILY REACHING THE UPPER
80S TO LOWER 90S ACROSS MOST OF THE FORECAST AREA, WITH DEWPOINTS
CLIMBING INTO THE LOWER AND MIDDLE 60S. WE WILL CONTINUE A MENTION
OF THIS EXPECTED HEAT WAVE IN OUR HAZARDOUS WEATHER OUTLOOK, AS HEAT
INDEX VALUES LOOK TO RANGE BETWEEN 90 TO 95 DEGREES.
FOR THE LATTER PART OF THE WEEKEND INTO SUNDAY, THE SURFACE HIGH
PRESSURE AND THE MID-LEVEL RIDGE WILL BOTH BEGIN TO SHIFT EASTWARD,
AS LOW PRESSURE TAKES SHAPE AROUND THE GREAT LAKES WITH A TRAILING
COLD FRONT. WITH THE OVERALL PATTERN BEGINNING TO BREAK DOWN, MODEL
RELATIVE HUMIDITIES INDICATE INCREASING MOISTURE AND CLOUDINESS FOR
SUNDAY, WITH MAXIMUM TEMPERATURES MOSTLY IN THE MIDDLE TO UPPER 80S
ACROSS THE REGION. WE HAVE RETAINED INCREASING POPS FOR
SHWRS/T-STORMS FROM WEST TO EAST ACROSS THE FORECAST AREA DURING
SUNDAY AND SUNDAY NIGHT AS THERE LOOKS TO BE AMPLE INSTABILITY AHEAD
OF THE APPROACHING FRONT. MOST OF THE MODEL GUIDANCE HAS THE COLD
FRONT PASSING THROUGH THE REGION DURING MONDAY, ALTHOUGH THERE ARE
TIMING DIFFERENCES BETWEEN THE GFS, ECMWF, AND OTHERS. AT THIS
EXTENDED TIME RANGE, WE USED A BLEND OF WPC GUIDANCE WITH CONTINUITY
FOR MOST ELEMENTS, INCLUDING TEMPERATURES AND WINDS, AND WE KEPT
HIGH CHANCE POPS IN PLACE ACROSS THE REGION THROUGH MOST OF MONDAY.
WHILE THE FINER DETAILS WILL BE WORKED OUT AS WE GET CLOSER IN TIME
TO THE FRONTAL PASSAGE AND THE MODELS ALIGN MORE WITH REGARDS TO THE
TIMING OF THE FRONT, WHAT IS APPARENT IS THAT TEMPERATURES WILL
RETURN CLOSER TO SEASONAL AVERAGES FOR MONDAY AND TUESDAY.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
VFR PREVIALING FOR THIS AFTERNOON PREVAILING. SCATTERED SHOWERS
AND TSTMS POSSIBLE WITH BRIEF MVFR TO IFR CONSITIONS. IF THESE
BANDS...ESPECIALLY THE NRN PA- NNJ BAND DEVELOP...EXPECT A BRIEF
35-40 KT GUSTY NW OUTFLOW FROM THE STORMS.
TONIGHT...A LINE OF DYING SHOWERS AND EMBEDDED TSTMS SHOULD SLIDE
ESEWD FROM VCNTY KRDG-KTTN AROUND 00Z DYING OUT NEAR KPNE-KACY
AROUND 02-03Z. OTRW VFR WITH POSSIBLE MVFR HAZE FOG TOWARD DAWN
THURSDAY.
OUTLOOK...
THURSDAY THROUGH SATURDAY...MAINLY VFR CONDITIONS EXPECTED WITH
SOUTHWESTERLY WINDS. SOME LOCAL REDUCED VSBYS POSSIBLE EACH MORNING
IN HAZE.
SUNDAY...MAINLY VFR CONDITIONS THROUGH THE DAY, WITH SUB-VFR
CONDITIONS POSSIBLE IN SHWRS/T-STORMS BY LATE-DAY AND INTO SUNDAY
NIGHT.
&&
.MARINE...
A GENERALLY SSW 10-20 KT FLOW PREVAILS TODAY AND TONIGHT WITH NO
HEADLINE. MAYBE A BIT OF VSBY RESTRICTION IN HAZE EARLY THURSDAY
MORNING. WINDS WILL PROBABLY TURN SSE ALONG THE COASTS FOR A TIME
THIS AFTN BUT EVEN THERE..THE WSW GRADIENT FLOW MAY PREVENT MUCH
OF AN EAST OF SOUTH TURN.
OUTLOOK...
WITH OFFSHORE HIGH PRESSURE INFLUENCING THE MID ATLANTIC REGION AND
OUR WATERS, SUB-SCA CONDITIONS ARE EXPECTED ON OUR WATERS FROM
THURSDAY THROUGH THE FIRST PART OF THE WEEKEND. WINDS THROUGH THIS
TIME FRAME WILL MAINLY BE OUT OF THE SOUTHWEST, WITH SEAS IN THE 3
TO 4 FOOT RANGE FOR OUR COASTAL WATERS AND 1 TO 3 FOOT SEAS IN
DELAWARE BAY. GOING INTO SUNDAY WITH HIGH PRESSURE DRIFTING FARTHER
EAST INTO THE CENTRAL ATLANTIC AND A COLD FRONT APPROACHING THE
REGION FROM THE WEST, WE EXPECT WIND GUSTS AND SEAS TO REACH SMALL
CRAFT ADVISORY LEVELS.
&&
.RIP CURRENTS...
TODAYS RIP CURRENT RISK IS AGAIN LOW BASED ON A 2 FT SWELL 9 SECOND
PERIOD AND RAN IT EITHER WITH A WIND 2115 OR 1812 WITH NEARLY
IDENTICAL LOW RISK RESULTS FOR BOTH NJ AND DE.
RIP CURRENT AWARENESS WEEK JUNE 2 THROUGH 8.
PSA`S WILL AIR ON KPHI NWR AND POST DAILY AROUND 545 AM. A SHORT
AWARENESS PRESS CONFERENCE IN SURF CITY - LBI, TUE JUNE 4 2PM FOR
THOSE MEDIA REPRESENTATIVES THAT ARE INTERESTED IN RAISING RIP
CURRENT AWARENESS AND CONDITIONS FAVORING UNGUARDED LIFE THREATENING
DANGER IN THE OCEAN SURF ZONE.
MORE ON THIS IN THE AFD NEXT MONDAY JUNE 3.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KLINE
NEAR TERM...GIGI
SHORT TERM...DRAG
LONG TERM...KLINE
AVIATION...DRAG/KLINE
MARINE...DRAG/KLINE
RIP CURRENTS...DRAG
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
924 AM EDT WED MAY 29 2013
.SYNOPSIS...
A WARM FRONT WILL CONTINUE TO LIFT NORTHWARD THROUGH TODAY AS AN
AREA OF HIGH PRESSURE OFF THE EASTERN SEABOARD SPREADS ITS INFLUENCE
INTO THE MID ATLANTIC REGION, BRINGING INCREASING HEAT AND HUMIDITY
TO THE AREA THROUGH THIS WEEKEND. FOR EARLY NEXT WEEK, A LOW
PRESSURE SYSTEM EMERGING FROM AROUND THE GREAT LAKES WILL SEND A
COLD FRONT THROUGH OUR REGION BY MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LAST COUPLE OF HOURS SPC WRF RUN OF VERIFYING WELL HAS ENDED.
LATEST COUPLE OF HRRR RUNS ARE VERIFYING BETTER WITH ONGOING
CONVECTION AND IF PAST PERFORMANCE IS AN INDICATION OF FUTURE
TRENDS IT WAS USED FOR ADJUSTMENTS IN THE NEAR TERM. THE EMPHASIS
OF ALL OF THE MESOSCALE MODELS THOUGH HAS REMAINED THE SAME AS THE
SYNOPTIC SCALE FORCING FOR THE MOST ORGANIZED CONVECTION IS IN THE
NORTHERN PART OF OUR CWA. WHERE THE HRRR AND SPC WRF DIFFER ARE
WITH THE SOUTHERN EXTENSION AND DEVELOPMENT. FORECAST SOUNDING
CONVECTIVE TEMPS SUGGEST LATER IN THE AFTERNOON ALSO. THE FORMER
HAS LESS AND WE LOWERED POPS SOUTH. OVERALL THEY ARE PRETTY
SIMILAR NORTH WHERE ENHANCED WORDING WAS KEPT.
THE 12Z UA ANALYSIS IS SHOWING A LLJ CENTERED OVER LAKE ERIE WITH
THE 850MB THETA E RIDGE INTO THE FINGER LAKES OF NEW YORK. AT
500MB THOUGH WE ARE ADVECTING WARMER AIR INTO OUR CWA. REGARDLESS
THE CONVECTIVE TEMPERATURE IS FORECAST TO BE REACHED LATE IN THE
AFTERNOON.
12Z SOUNDINGS SUGGEST NO BIG ADJUSTMENTS NEEDED FOR MAX TEMPS. THE
STRATUS IS SLOWING THE RISE NORTH WHICH WAS THE BIGGEST CHANGE,
BUT THE OVERALL OUTCOME IS EXPECTED TO BE SIMILAR.
NOT MUCH 0-6KM BULK SHEAR SUPPORT FOR SVR WIND IN OUR AREA BUT A
GUSTY NW WIND OUTFLOW OF 35-40 KT IS POSSIBLE FROM KMPO TO KFWN
BETWEEN 22 AND 24Z AND POSSIBLY DOWN TO KRDG/KABE AND KTTN BETWEEN
00Z-02Z. ADDITIONALLY TT UP AROUND 50C HAS ME A LITTLE CONCERNED
BUT ON THE OTHER SIDE OF THE COIN...KI IS NOT MUCH LARGER THAN
33-34C IN THE BAND. PLEASE REFERENCE SWODY1 AND ANY SPC MCD`S
ISSUED THIS AFTN PLUS UPDATED LOCAL KPHI DISCUSSIONS.
SINCE THE NAM SPITS OUT QPF PRIOR TO 18Z...THAT TRIMS ITS BL TEMP AND
2M TEMPS BY 1-3 DEGS AND WE SEE THE DRY RAP MODEL FCSTG LOWER 90S
19Z-22Z FOR S NJ AND THE PHILLY AREA. THAT MIGHT BE 2 DEGS TO HIGH
FOR 15C AT 850 BUT ITS QUITE POSSIBLE THAT 90F WILL OCCUR AND THAT
OUR HEAT WAVE BEGINS AROUND 3-4PM THIS AFTN. THE RAPRUC CONTINUES
TO HAMMER 91-92F IN SNJ CENTRAL DE.
GRADIENT SW WIND GUST 15-20 MPH THIS AFTN. COOLING SEA BREEZES
WILL STRUGGLE TO PENETRATE INLAND IN THIS GRADIENT FLOW BEHIND THE
WFRONT AND EVEN KACY SHOULD REACH 90F WITH ONLY THE NEAREST 3MI OF
THE COAST RECEIVING THE BENEFIT OF COOLING SLY OCEAN BREEZES.
SINCE OUR HI IS BELOW 96. NO HEAT ADVY NOR EXCESSIVE HEAT WATCHES
BUT EMERGENCY MANAGEMENT HAS BEEN BRIEFED ON THE PROBABLE 3-5 DAY
EARLY SEASON HEAT WAVE FOR THE I95 CORRIDOR.
GENERALLY 50 50 BLENDED GFS NAM GUIDANCE BUT USED THE WARMER 2M
TEMPS FROM THE NAM/RGEM AND RAP-RUC TO MODIFY THE PCPN TAINTED NAM
MOS OUTPUT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
THE LAST BAND OF WHATEVER HEAVY CONVECTION MOVES ESEWD FROM VCNTY
KRDG-KTTN AT AROUND 00-01Z AND WEAKENS JUST TO THE N OF KPNE AND
KACY AROUND 03Z. OTRW A WARM SUMMERLIKE NIGHT.
50 50 BLENDED 00Z/29 GFS/NAM GUIDANCE.
PATCHY FOG POSSIBLE LATE BUT PROBABLY NOTHING LIKE EARLY THIS
MORNING.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
TO START THE LONG TERM, SURFACE HIGH PRESSURE WILL BE FOUND OVER THE
CENTRAL ATLANTIC, EXTENDING ITS INFLUENCE WESTWARD INTO THE MIDDLE
ATLANTIC STATES. MEANWHILE, STRONG MID-LEVEL RIDGING WILL ALSO BE
TAKING HOLD ACROSS THE REGION. THIS LOOKS TO BE THE BEGINNING OF OUR
FIRST POTENTIAL HEAT WAVE OF THE SEASON, AS A STRENGTHENING
SOUTHWESTERLY FLOW THROUGH THE END OF THE WORK WEEK AND INTO THE
WEEKEND WILL BRING INCREASING HEAT AND HUMIDITY. MODEL 850MB AND
925MB TEMPS SUPPORT MAXIMUM TEMPERATURES EASILY REACHING THE UPPER
80S TO LOWER 90S ACROSS MOST OF THE FORECAST AREA, WITH DEWPOINTS
CLIMBING INTO THE LOWER AND MIDDLE 60S. WE WILL CONTINUE A MENTION
OF THIS EXPECTED HEAT WAVE IN OUR HAZARDOUS WEATHER OUTLOOK, AS HEAT
INDEX VALUES LOOK TO RANGE BETWEEN 90 TO 95 DEGREES.
FOR THE LATTER PART OF THE WEEKEND INTO SUNDAY, THE SURFACE HIGH
PRESSURE AND THE MID-LEVEL RIDGE WILL BOTH BEGIN TO SHIFT EASTWARD,
AS LOW PRESSURE TAKES SHAPE AROUND THE GREAT LAKES WITH A TRAILING
COLD FRONT. WITH THE OVERALL PATTERN BEGINNING TO BREAK DOWN, MODEL
RELATIVE HUMIDITIES INDICATE INCREASING MOISTURE AND CLOUDINESS FOR
SUNDAY, WITH MAXIMUM TEMPERATURES MOSTLY IN THE MIDDLE TO UPPER 80S
ACROSS THE REGION. WE HAVE RETAINED INCREASING POPS FOR
SHWRS/T-STORMS FROM WEST TO EAST ACROSS THE FORECAST AREA DURING
SUNDAY AND SUNDAY NIGHT AS THERE LOOKS TO BE AMPLE INSTABILITY AHEAD
OF THE APPROACHING FRONT. MOST OF THE MODEL GUIDANCE HAS THE COLD
FRONT PASSING THROUGH THE REGION DURING MONDAY, ALTHOUGH THERE ARE
TIMING DIFFERENCES BETWEEN THE GFS, ECMWF, AND OTHERS. AT THIS
EXTENDED TIME RANGE, WE USED A BLEND OF WPC GUIDANCE WITH CONTINUITY
FOR MOST ELEMENTS, INCLUDING TEMPERATURES AND WINDS, AND WE KEPT
HIGH CHANCE POPS IN PLACE ACROSS THE REGION THROUGH MOST OF MONDAY.
WHILE THE FINER DETAILS WILL BE WORKED OUT AS WE GET CLOSER IN TIME
TO THE FRONTAL PASSAGE AND THE MODELS ALIGN MORE WITH REGARDS TO THE
TIMING OF THE FRONT, WHAT IS APPARENT IS THAT TEMPERATURES WILL
RETURN CLOSER TO SEASONAL AVERAGES FOR MONDAY AND TUESDAY.
&&
.AVIATION /13Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
AFTER 12Z...ANY REMAINING IFR/LIFR FOG/STRATUS QUICKLY DISSIPATES
BY 13Z AND BECOMES VFR SCT-BKN AOA 5000 FT WITH A SW WIND G15-20 KT
IN THE AFTN. SCATTERED SHOWERS AND TSTMS POSSIBLE. IF THESE
BANDS...ESPECIALLY THE NRN PA-NNJ BAND DEVELOP...EXPECT A BRIEF
35-40 KT GUSTY NW OUTFLOW FROM THE STORMS.
TONIGHT...A LINE OF DYING SHOWERS AND EMBEDDED TSTMS SHOULD SLIDE
ESEWD FROM VCNTY KRDG-KTTN AROUND 00Z DYING OUT NEAR KPNE-KACY
AROUND 02-03Z. OTRW VFR WITH POSSIBLE MVFR HAZE FOG TOWARD DAWN
THURSDAY.
OUTLOOK...
THURSDAY THROUGH SATURDAY...MAINLY VFR CONDITIONS EXPECTED WITH
SOUTHWESTERLY WINDS. SOME LOCAL REDUCED VSBYS POSSIBLE EACH MORNING
IN HAZE.
SUNDAY...MAINLY VFR CONDITIONS THROUGH THE DAY, WITH SUB-VFR
CONDITIONS POSSIBLE IN SHWRS/T-STORMS BY LATE-DAY AND INTO SUNDAY
NIGHT.
&&
.MARINE...
SEAS AND WINDS WERE FCST MUCH TOO HIGH ON THE ATLC WATERS TUE AFTN
AND NIGHT AND 44009..WITH ITS WIND DATA PROBLEMS AND ALL..STILL
BARELY JUST MADE IT 5 FT AT 11PM EDT AND NOW AROUND 4FT.
THEREFORE THE SCA WAS DISCONTINUED.
OTRW A GENERALLY SSW 10-20 KT FLOW PREVAILS TODAY AND TONIGHT WITH
NO HEADLINE. MAYBE A BIT OF VSBY RESTRICTION IN FOG AND HAZE TIL
9 AM EDT AND POSSIBLY IN HAZE EARLY THURSDAY MORNING. WINDS WILL
PROBABLY TURN SSE ALONG THE COASTS FOR A TIME THIS AFTN BUT EVEN
THERE..THE WSW GRADIENT FLOW MAY PREVENT MUCH OF AN EAST OF SOUTH
TURN.
OUTLOOK...
WITH OFFSHORE HIGH PRESSURE INFLUENCING THE MID ATLANTIC REGION AND
OUR WATERS, SUB-SCA CONDITIONS ARE EXPECTED ON OUR WATERS FROM
THURSDAY THROUGH THE FIRST PART OF THE WEEKEND. WINDS THROUGH THIS
TIME FRAME WILL MAINLY BE OUT OF THE SOUTHWEST, WITH SEAS IN THE 3
TO 4 FOOT RANGE FOR OUR COASTAL WATERS AND 1 TO 3 FOOT SEAS IN
DELAWARE BAY. GOING INTO SUNDAY WITH HIGH PRESSURE DRIFTING FARTHER
EAST INTO THE CENTRAL ATLANTIC AND A COLD FRONT APPROACHING THE
REGION FROM THE WEST, WE EXPECT WIND GUSTS AND SEAS TO REACH SMALL
CRAFT ADVISORY LEVELS.
&&
.RIP CURRENTS...
TODAYS RIP CURRENT RISK IS AGAIN LOW BASED ON A 2 FT SWELL 9 SECOND
PERIOD AND RAN IT EITHER WITH A WIND 2115 OR 1812 WITH NEARLY
IDENTICAL LOW RISK RESULTS FOR BOTH NJ AND DE.
RIP CURRENT AWARENESS WEEK JUNE 2 THROUGH 8.
PSA`S WILL AIR ON KPHI NWR AND POST DAILY AROUND 545 AM. A SHORT
AWARENESS PRESS CONFERENCE IN SURF CITY - LBI, TUE JUNE 4 2PM FOR
THOSE MEDIA REPRESENTATIVES THAT ARE INTERESTED IN RAISING RIP
CURRENT AWARENESS AND CONDITIONS FAVORING UNGUARDED LIFE THREATENING
DANGER IN THE OCEAN SURF ZONE.
MORE ON THIS IN THE AFD NEXT MONDAY JUNE 3.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KLINE
NEAR TERM...DRAG/GIGI
SHORT TERM...DRAG
LONG TERM...KLINE
AVIATION...DRAG/KLINE
MARINE...DRAG/KLINE
RIP CURRENTS...DRAG
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
804 AM EDT WED MAY 29 2013
.SYNOPSIS...
A WARM FRONT WILL CONTINUE TO LIFT NORTHWARD THROUGH TODAY AS AN
AREA OF HIGH PRESSURE OFF THE EASTERN SEABOARD SPREADS ITS INFLUENCE
INTO THE MID ATLANTIC REGION, BRINGING INCREASING HEAT AND HUMIDITY
TO THE AREA THROUGH THIS WEEKEND. FOR EARLY NEXT WEEK, A LOW
PRESSURE SYSTEM EMERGING FROM AROUND THE GREAT LAKES WILL SEND A
COLD FRONT THROUGH OUR REGION BY MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE DENSE FOG ADVISORY WAS ALLOWED TO EXPIRE.
THE PAST TWO CYCLES OF THE SPCWRF HAD WHAT I THOUGHT WERE EXCELLENT
HOURLY RADAR SIMULATIONS OF WHAT HAS TRANSPIRED FROM LERIE TO THE
DELMARVA INCLUDING OUR FORECAST AREA. THAT SPCWRF IS RELIED ON
HEAVILY AGAIN FOR THE UPCOMING FORECAST FOR TODAY AND TONIGHT.
TODAY...THE 00Z/29 VERSION OF THE SPCWRF IS MORE VIGOROUS ACROSS
OUR AREA THIS AFTN/EVENING THAN I ANTICIPATED PRIOR TO BEGINNING
THE SHIFT. STILL NOT QUITE SURE IF TWO BANDS OF DECENT CONVECTION
CAN DEVELOP SEWD ACROSS OUR FCST AREA...THE FIRST SCT CONVECTIVE
ELEMENTS FROM KDCA- KBLM AROUND 20Z AND WEAKENING ESEWD OVER FAR
SNJ NEAR SUNSET.
THE MORE SIGNIFICANT BAND OF STRONG STORMS FOR WHICH I HAVE MUCH
GREATER CONFIDENCE...WILL PROBABLY DEVELOP NEAR THE NY/PA BORDER
MID OR LATE AFTN AND ORGANIZE ESEWD TO NEAR I80 BY AROUND 8 PM EDT.
GFS ML CAPE WILL RISE TO NEAR 1500J ALONG I95 THIS AFTN. THIS
SUPPLIES DECENT ENERGY FOR CONVECTION PROVIDED ITS NOT TOO DRY
ALOFT AND THAT THERE CAN BE SOME SORT OF BOUNDARY TRIGGERING AND
ORGANIZING THE CONVECTION. THE 06Z RAP-RUC AGREES ON THIS
SCENARIO.
NOT MUCH 0-6KM BULK SHEAR SUPPORT FOR SVR WIND IN OUR AREA BUT A
GUSTY NW WIND OUTFLOW OF 35-40 KT IS POSSIBLE FROM KMPO TO KFWN
BETWEEN 22 AND 24Z AND POSSIBLY DOWN TO KRDG/KABE AND KTTN BETWEEN
00Z-02Z. ADDITIONALLY TT UP AROUND 50C HAS ME A LITTLE CONCERNED
BUT ON THE OTHER SIDE OF THE COIN...KI IS NOT MUCH LARGER THAN
33-342C IN THE BAND SO AM NOT CONVINCED THAT THE SPC WRF VIGOR
WILL BE REALIZED. NEVERTHELESS...THIS MODEL HAS GARNERED MY
RESPECT SINCE ITS GENERALLY A SUCCESSFUL SIMULATOR OF THE FUTURE
REALITY. PLEASE REFERENCE SWODY1 AND ANY SPC MCD`S ISSUED THIS
AFTN PLUS UPDATED LOCAL KPHI DISCUSSIONS.
SINCE THE NAM SPITS OUT QPF PRIOR TO 18Z...THAT TRIMS ITS BL TEMP AND
2M TEMPS BY 1-3 DEGS AND WE SEE THE DRY RAP MODEL FCSTG LOWER 90S
19Z-22Z FOR S NJ AND THE PHILLY AREA. THAT MIGHT BE 2 DEGS TO HIGH
FOR 15C AT 850 BUT ITS QUITE POSSIBLE THAT 90F WILL OCCUR AND THAT
OUR HEAT WAVE BEGINS AROUND 3-4PM THIS AFTN. THE RAPRUC CONTINUES
TO HAMMER 91-92F IN SNJ CENTRAL DE.
GRADIENT SW WIND GUST 15-20 MPH THIS AFTN. COOLING SEA BREEZES
WILL STRUGGLE TO PENETRATE INLAND IN THIS GRADIENT FLOW BEHIND THE
WFRONT AND EVEN KACY SHOULD REACH 90F WITH ONLY THE NEAREST 3MI OF
THE COAST RECEIVING THE BENEFIT OF COOLING SLY OCEAN BREEZES.
SINCE OUR HI IS BELOW 96. NO HEAT ADVY NOR EXCESSIVE HEAT WATCHES
BUT EMERGENCY MANAGEMENT HAS BEEN BRIEFED ON THE PROBABLE 3-5 DAY
EARLY SEASON HEAT WAVE FOR THE I95 CORRIDOR.
GENERALLY 50 50 BLENDED GFS NAM GUIDANCE BUT USED THE WARMER 2M
TEMPS FROM THE NAM/RGEM AND RAP-RUC TO MODIFY THE PCPN TAINTED NAM
MOS OUTPUT.
PHL AROUND 89 TODAY AND 90-91 IN SNJ EVEN TO KACY AND S DE VCNTY KGED.
THE 06Z NAM IS SLIGHTLY WARMER AND SO AM CONFIDENT OF AT LEAST 89 IN
PHL AND THERE IS A 50 PCT CHC PHL WILL NUDGE 90F WITH A 20 PCT
REACHING 92. CONFIDENCE ON REACHING THE MAX TEMPS VALUES FCST N OF I80
IS LESS THAN AVG.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
THE LAST BAND OF WHATEVER HEAVY CONVECTION MOVES ESEWD FROM VCNTY
KRDG-KTTN AT AROUND 00-01Z AND WEAKENS JUST TO THE N OF KPNE AND
KACY AROUND 03Z. OTRW A WARM SUMMERLIKE NIGHT.
50 50 BLENDED 00Z/29 GFS/NAM GUIDANCE.
PATCHY FOG POSSIBLE LATE BUT PROBABLY NOTHING LIKE EARLY THIS
MORNING.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
TO START THE LONG TERM, SURFACE HIGH PRESSURE WILL BE FOUND OVER THE
CENTRAL ATLANTIC, EXTENDING ITS INFLUENCE WESTWARD INTO THE MIDDLE
ATLANTIC STATES. MEANWHILE, STRONG MID-LEVEL RIDGING WILL ALSO BE
TAKING HOLD ACROSS THE REGION. THIS LOOKS TO BE THE BEGINNING OF OUR
FIRST POTENTIAL HEAT WAVE OF THE SEASON, AS A STRENGTHENING
SOUTHWESTERLY FLOW THROUGH THE END OF THE WORK WEEK AND INTO THE
WEEKEND WILL BRING INCREASING HEAT AND HUMIDITY. MODEL 850MB AND
925MB TEMPS SUPPORT MAXIMUM TEMPERATURES EASILY REACHING THE UPPER
80S TO LOWER 90S ACROSS MOST OF THE FORECAST AREA, WITH DEWPOINTS
CLIMBING INTO THE LOWER AND MIDDLE 60S. WE WILL CONTINUE A MENTION
OF THIS EXPECTED HEAT WAVE IN OUR HAZARDOUS WEATHER OUTLOOK, AS HEAT
INDEX VALUES LOOK TO RANGE BETWEEN 90 TO 95 DEGREES.
FOR THE LATTER PART OF THE WEEKEND INTO SUNDAY, THE SURFACE HIGH
PRESSURE AND THE MID-LEVEL RIDGE WILL BOTH BEGIN TO SHIFT EASTWARD,
AS LOW PRESSURE TAKES SHAPE AROUND THE GREAT LAKES WITH A TRAILING
COLD FRONT. WITH THE OVERALL PATTERN BEGINNING TO BREAK DOWN, MODEL
RELATIVE HUMIDITIES INDICATE INCREASING MOISTURE AND CLOUDINESS FOR
SUNDAY, WITH MAXIMUM TEMPERATURES MOSTLY IN THE MIDDLE TO UPPER 80S
ACROSS THE REGION. WE HAVE RETAINED INCREASING POPS FOR
SHWRS/T-STORMS FROM WEST TO EAST ACROSS THE FORECAST AREA DURING
SUNDAY AND SUNDAY NIGHT AS THERE LOOKS TO BE AMPLE INSTABILITY AHEAD
OF THE APPROACHING FRONT. MOST OF THE MODEL GUIDANCE HAS THE COLD
FRONT PASSING THROUGH THE REGION DURING MONDAY, ALTHOUGH THERE ARE
TIMING DIFFERENCES BETWEEN THE GFS, ECMWF, AND OTHERS. AT THIS
EXTENDED TIME RANGE, WE USED A BLEND OF WPC GUIDANCE WITH CONTINUITY
FOR MOST ELEMENTS, INCLUDING TEMPERATURES AND WINDS, AND WE KEPT
HIGH CHANCE POPS IN PLACE ACROSS THE REGION THROUGH MOST OF MONDAY.
WHILE THE FINER DETAILS WILL BE WORKED OUT AS WE GET CLOSER IN TIME
TO THE FRONTAL PASSAGE AND THE MODELS ALIGN MORE WITH REGARDS TO THE
TIMING OF THE FRONT, WHAT IS APPARENT IS THAT TEMPERATURES WILL
RETURN CLOSER TO SEASONAL AVERAGES FOR MONDAY AND TUESDAY.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
AFTER 12Z...ANY REMAINING IFR/LIFR FOG/STRATUS QUICKLY DISSIPATES
BY 13Z AND BECOMES VFR SCT-BKN AOA 5000 FT WITH A SW WIND G15-20 KT
IN THE AFTN. TWO BANDS OF TSTMS ARE MODELED BY THE SPCWRF AS DISCUSSED
IN DETAIL IN OUR NEAR TERM SECTION. HAVE FOLLOWED THIS FOR THE 06Z
AND UPCOMING 12Z TAFS WITH SUPPORT FROM THE LATEST 07Z RAPRUC. IF
THESE BANDS...ESPECIALLY THE NRN PA-NNJ BAND DEVELOP...EXPECT A
BRIEF 35-40 KT GUSTY NW OUTFLOW FROM THE STORMS.
TONIGHT...A LINE OF DYING SHOWERS AND EMBEDDED TSTMS SHOULD SLIDE
ESEWD FROM VCNTY KRDG-KTTN AROUND 00Z DYING OUT NEAR KPNE-KACY
AROUND 02-03Z. OTRW VFR WITH POSSIBLE MVFR HAZE FOG TOWARD DAWN
THURSDAY.
OUTLOOK...
THURSDAY THROUGH SATURDAY...MAINLY VFR CONDITIONS EXPECTED WITH
SOUTHWESTERLY WINDS. SOME LOCAL REDUCED VSBYS POSSIBLE EACH MORNING
IN HAZE.
SUNDAY...MAINLY VFR CONDITIONS THROUGH THE DAY, WITH SUB-VFR
CONDITIONS POSSIBLE IN SHWRS/T-STORMS BY LATE-DAY AND INTO SUNDAY
NIGHT.
&&
.MARINE...
SEAS AND WINDS WERE FCST MUCH TOO HIGH ON THE ATLC WATERS TUE AFTN
AND NIGHT AND 44009..WITH ITS WIND DATA PROBLEMS AND ALL..STILL
BARELY JUST MADE IT 5 FT AT 11PM EDT AND NOW AROUND 4FT.
THEREFORE THE SCA WAS DISCONTINUED.
OTRW A GENERALLY SSW 10-20 KT FLOW PREVAILS TODAY AND TONIGHT WITH
NO HEADLINE. MAYBE A BIT OF VSBY RESTRICTION IN FOG AND HAZE TIL
9 AM EDT AND POSSIBLY IN HAZE EARLY THURSDAY MORNING. WINDS WILL
PROBABLY TURN SSE ALONG THE COASTS FOR A TIME THIS AFTN BUT EVEN
THERE..THE WSW GRADIENT FLOW MAY PREVENT MUCH OF AN EAST OF SOUTH
TURN.
OUTLOOK...
WITH OFFSHORE HIGH PRESSURE INFLUENCING THE MID ATLANTIC REGION AND
OUR WATERS, SUB-SCA CONDITIONS ARE EXPECTED ON OUR WATERS FROM
THURSDAY THROUGH THE FIRST PART OF THE WEEKEND. WINDS THROUGH THIS
TIME FRAME WILL MAINLY BE OUT OF THE SOUTHWEST, WITH SEAS IN THE 3
TO 4 FOOT RANGE FOR OUR COASTAL WATERS AND 1 TO 3 FOOT SEAS IN
DELAWARE BAY. GOING INTO SUNDAY WITH HIGH PRESSURE DRIFTING FARTHER
EAST INTO THE CENTRAL ATLANTIC AND A COLD FRONT APPROACHING THE
REGION FROM THE WEST, WE EXPECT WIND GUSTS AND SEAS TO REACH SMALL
CRAFT ADVISORY LEVELS.
&&
.RIP CURRENTS...
TODAYS RIP CURRENT RISK IS AGAIN LOW BASED ON A 2 FT SWELL 9 SECOND
PERIOD AND RAN IT EITHER WITH A WIND 2115 OR 1812 WITH NEARLY
IDENTICAL LOW RISK RESULTS FOR BOTH NJ AND DE.
RIP CURRENT AWARENESS WEEK JUNE 2 THROUGH 8.
PSA`S WILL AIR ON KPHI NWR AND POST DAILY AROUND 545 AM. A SHORT
AWARENESS PRESS CONFERENCE IN SURF CITY - LBI, TUE JUNE 4 2PM FOR
THOSE MEDIA REPRESENTATIVES THAT ARE INTERESTED IN RAISING RIP
CURRENT AWARENESS AND CONDITIONS FAVORING UNGUARDED LIFE THREATENING
DANGER IN THE OCEAN SURF ZONE.
MORE ON THIS IN THE AFD NEXT MONDAY JUNE 3.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KLINE
NEAR TERM...DRAG
SHORT TERM...DRAG
LONG TERM...KLINE
AVIATION...DRAG/KLINE
MARINE...DRAG/KLINE
RIP CURRENTS...DRAG
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
624 AM EDT WED MAY 29 2013
.SYNOPSIS...
A WARM FRONT WILL CONTINUE TO LIFT NORTHWARD THROUGH TODAY AS AN
AREA OF HIGH PRESSURE OFF THE EASTERN SEABOARD SPREADS ITS INFLUENCE
INTO THE MID ATLANTIC REGION, BRINGING INCREASING HEAT AND HUMIDITY
TO THE AREA THROUGH THIS WEEKEND. FOR EARLY NEXT WEEK, A LOW
PRESSURE SYSTEM EMERGING FROM AROUND THE GREAT LAKES WILL SEND A
COLD FRONT THROUGH OUR REGION BY MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A DENSE FOG ADVISORY WAS POSTED WHERE VSBY NEAR OR BELOW 1/4 MI
AND NOW EXTENDED THRU 8AM THO IMPROVEMENT SHOULD BE NOTICED BEGINNING
AROUND 7 AM. DROPPED THE ADVY NW BURLINGTON CTY NJ.
OTRW SHOWERS ENDING BY 7 OR 8 AM IN POCONOS AND NW NJ.
THE PAST TWO CYCLES OF THE SPCWRF HAD WHAT I THOUGHT WERE EXCELLENT
HOURLY RADAR SIMULATIONS OF WHAT HAS TRANSPIRED FROM LERIE TO THE
DELMARVA INCLUDING OUR FORECAST AREA. THAT SPCWRF IS RELIED ON
HEAVILY AGAIN FOR THE UPCOMING FORECAST FOR TODAY AND TONIGHT.
TODAY...THE 00Z/29 VERSION OF THE SPCWRF IS MORE VIGOROUS ACROSS
OUR AREA THIS AFTN/EVENING THAN I ANTICIPATED PRIOR TO BEGINNING
THE SHIFT. STILL NOT QUITE SURE IF TWO BANDS OF DECENT CONVECTION
CAN DEVELOP SEWD ACROSS OUR FCST AREA...THE FIRST SCT CONVECTIVE
ELEMENTS FROM KDCA- KBLM AROUND 20Z AND WEAKENING ESEWD OVER FAR
SNJ NEAR SUNSET.
THE MORE SIGNIFICANT BAND OF STRONG STORMS FOR WHICH I HAVE MUCH
GREATER CONFIDENCE...WILL PROBABLY DEVELOP NEAR THE NY/PA BORDER
MID OR LATE AFTN AND ORGANIZE ESEWD TO NEAR I80 BY AROUND 8 PM EDT.
GFS ML CAPE WILL RISE TO NEAR 1500J ALONG I95 THIS AFTN. THIS
SUPPLIES DECENT ENERGY FOR CONVECTION PROVIDED ITS NOT TOO DRY
ALOFT AND THAT THERE CAN BE SOME SORT OF BOUNDARY TRIGGERING AND
ORGANIZING THE CONVECTION. THE 06Z RAP-RUC AGREES ON THIS
SCENARIO.
NOT MUCH 0-6KM BULK SHEAR SUPPORT FOR SVR WIND IN OUR AREA BUT A
GUSTY NW WIND OUTFLOW OF 35-40 KT IS POSSIBLE FROM KMPO TO KFWN
BETWEEN 22 AND 24Z AND POSSIBLY DOWN TO KRDG/KABE AND KTTN BETWEEN
00Z-02Z. ADDITIONALLY TT UP AROUND 50C HAS ME A LITTLE CONCERNED
BUT ON THE OTHER SIDE OF THE COIN...KI IS NOT MUCH LARGER THAN
33-342C IN THE BAND SO AM NOT CONVINCED THAT THE SPC WRF VIGOR
WILL BE REALIZED. NEVERTHELESS...THIS MODEL HAS GARNERED MY
RESPECT SINCE ITS GENERALLY A SUCCESSFUL SIMULATOR OF THE FUTURE
REALITY. PLEASE REFERENCE SWODY1 AND ANY SPC MCD`S ISSUED THIS
AFTN PLUS UPDATED LOCAL KPHI DISCUSSIONS.
SINCE THE NAM SPITS OUT QPF PRIOR TO 18Z...THAT TRIMS ITS BL TEMP AND
2M TEMPS BY 1-3 DEGS AND WE SEE THE DRY RAP MODEL FCSTG LOWER 90S
19Z-22Z FOR S NJ AND THE PHILLY AREA. THAT MIGHT BE 2 DEGS TO HIGH
FOR 15C AT 850 BUT ITS QUITE POSSIBLE THAT 90F WILL OCCUR AND THAT
OUR HEAT WAVE BEGINS AROUND 3-4PM THIS AFTN. THE RAPRUC CONTINUES
TO HAMMER 91-92F IN SNJ CENTRAL DE.
GRADIENT SW WIND GUST 15-20 MPH THIS AFTN. COOLING SEA BREEZES
WILL STRUGGLE TO PENETRATE INLAND IN THIS GRADIENT FLOW BEHIND THE
WFRONT AND EVEN KACY SHOULD REACH 90F WITH ONLY THE NEAREST 3MI OF
THE COAST RECEIVING THE BENEFIT OF COOLING SLY OCEAN BREEZES.
SINCE OUR HI IS BELOW 96. NO HEAT ADVY NOR EXCESSIVE HEAT WATCHES
BUT EMERGENCY MANAGEMENT HAS BEEN BRIEFED ON THE PROBABLE 3-5 DAY
EARLY SEASON HEAT WAVE FOR THE I95 CORRIDOR.
GENERALLY 50 50 BLENDED GFS NAM GUIDANCE BUT USED THE WARMER 2M
TEMPS FROM THE NAM/RGEM AND RAP-RUC TO MODIFY THE PCPN TAINTED NAM
MOS OUTPUT.
PHL AROUND 89 TODAY AND 90-91 IN SNJ EVEN TO KACY AND S DE VCNTY KGED.
THE 06Z NAM IS SLIGHTLY WARMER AND SO AM CONFIDENT OF AT LEAST 89 IN
PHL AND THERE IS A 50 PCT CHC PHL WILL NUDGE 90F WITH A 20 PCT
REACHING 92. CONFIDENCE ON REACHING THE MAX TEMPS VALUES FCST N OF I80
IS LESS THAN AVG.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
THE LAST BAND OF WHATEVER HEAVY CONVECTION MOVES ESEWD FROM VCNTY
KRDG-KTTN AT AROUND 00-01Z AND WEAKENS JUST TO THE N OF KPNE AND
KACY AROUND 03Z. OTRW A WARM SUMMERLIKE NIGHT.
50 50 BLENDED 00Z/29 GFS/NAM GUIDANCE.
PATCHY FOG POSSIBLE LATE BUT PROBABLY NOTHING LIKE EARLY THIS
MORNING.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
TO START THE LONG TERM, SURFACE HIGH PRESSURE WILL BE FOUND OVER THE
CENTRAL ATLANTIC, EXTENDING ITS INFLUENCE WESTWARD INTO THE MIDDLE
ATLANTIC STATES. MEANWHILE, STRONG MID-LEVEL RIDGING WILL ALSO BE
TAKING HOLD ACROSS THE REGION. THIS LOOKS TO BE THE BEGINNING OF OUR
FIRST POTENTIAL HEAT WAVE OF THE SEASON, AS A STRENGTHENING
SOUTHWESTERLY FLOW THROUGH THE END OF THE WORK WEEK AND INTO THE
WEEKEND WILL BRING INCREASING HEAT AND HUMIDITY. MODEL 850MB AND
925MB TEMPS SUPPORT MAXIMUM TEMPERATURES EASILY REACHING THE UPPER
80S TO LOWER 90S ACROSS MOST OF THE FORECAST AREA, WITH DEWPOINTS
CLIMBING INTO THE LOWER AND MIDDLE 60S. WE WILL CONTINUE A MENTION
OF THIS EXPECTED HEAT WAVE IN OUR HAZARDOUS WEATHER OUTLOOK, AS HEAT
INDEX VALUES LOOK TO RANGE BETWEEN 90 TO 95 DEGREES.
FOR THE LATTER PART OF THE WEEKEND INTO SUNDAY, THE SURFACE HIGH
PRESSURE AND THE MID-LEVEL RIDGE WILL BOTH BEGIN TO SHIFT EASTWARD,
AS LOW PRESSURE TAKES SHAPE AROUND THE GREAT LAKES WITH A TRAILING
COLD FRONT. WITH THE OVERALL PATTERN BEGINNING TO BREAK DOWN, MODEL
RELATIVE HUMIDITIES INDICATE INCREASING MOISTURE AND CLOUDINESS FOR
SUNDAY, WITH MAXIMUM TEMPERATURES MOSTLY IN THE MIDDLE TO UPPER 80S
ACROSS THE REGION. WE HAVE RETAINED INCREASING POPS FOR
SHWRS/T-STORMS FROM WEST TO EAST ACROSS THE FORECAST AREA DURING
SUNDAY AND SUNDAY NIGHT AS THERE LOOKS TO BE AMPLE INSTABILITY AHEAD
OF THE APPROACHING FRONT. MOST OF THE MODEL GUIDANCE HAS THE COLD
FRONT PASSING THROUGH THE REGION DURING MONDAY, ALTHOUGH THERE ARE
TIMING DIFFERENCES BETWEEN THE GFS, ECMWF, AND OTHERS. AT THIS
EXTENDED TIME RANGE, WE USED A BLEND OF WPC GUIDANCE WITH CONTINUITY
FOR MOST ELEMENTS, INCLUDING TEMPERATURES AND WINDS, AND WE KEPT
HIGH CHANCE POPS IN PLACE ACROSS THE REGION THROUGH MOST OF MONDAY.
WHILE THE FINER DETAILS WILL BE WORKED OUT AS WE GET CLOSER IN TIME
TO THE FRONTAL PASSAGE AND THE MODELS ALIGN MORE WITH REGARDS TO THE
TIMING OF THE FRONT, WHAT IS APPARENT IS THAT TEMPERATURES WILL
RETURN CLOSER TO SEASONAL AVERAGES FOR MONDAY AND TUESDAY.
&&
.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THROUGH 12Z...IFR/LIFR CONDS IN ST/FOG MUCH OF E PA AND NNJ WITH
SCT SHOWERS ALONG AND N OF I80. CALM WIND. FOR FAR S NJ AND
DE...GENERALLY VFR WITH A S WIND OF 10 KT.
AFTER 12Z...ANY REMAINING IFR/LIFR FOG/STRATUS QUICKLY DISSIPATES
BY 13Z AND BECOMES VFR SCT-BKN AOA 5000 FT WITH A SW WIND G15-20 KT
IN THE AFTN. TWO BANDS OF TSTMS ARE MODELED BY THE SPCWRF AS DISCUSSED
IN DETAIL IN OUR NEAR TERM SECTION. HAVE FOLLOWED THIS FOR THE 06Z
AND UPCOMING 12Z TAFS WITH SUPPORT FROM THE LATEST 07Z RAPRUC. IF
THESE BANDS...ESPECIALLY THE NRN PA-NNJ BAND DEVELOP...EXPECT A
BRIEF 35-40 KT GUSTY NW OUTFLOW FROM THE STORMS.
TONIGHT...A LINE OF DYING SHOWERS AND EMBEDDED TSTMS SHOULD SLIDE
ESEWD FROM VCNTY KRDG-KTTN AROUND 00Z DYING OUT NEAR KPNE-KACY
AROUND 02-03Z. OTRW VFR WITH POSSIBLE MVFR HAZE FOG TOWARD DAWN
THURSDAY.
OUTLOOK...
THURSDAY THROUGH SATURDAY...MAINLY VFR CONDITIONS EXPECTED WITH
SOUTHWESTERLY WINDS. SOME LOCAL REDUCED VSBYS POSSIBLE EACH MORNING
IN HAZE.
SUNDAY...MAINLY VFR CONDITIONS THROUGH THE DAY, WITH SUB-VFR
CONDITIONS POSSIBLE IN SHWRS/T-STORMS BY LATE-DAY AND INTO SUNDAY
NIGHT.
&&
.MARINE...
SEAS AND WINDS WERE FCST MUCH TOO HIGH ON THE ATLC WATERS TUE AFTN
AND NIGHT AND 44009..WITH ITS WIND DATA PROBLEMS AND ALL..STILL
BARELY JUST MADE IT 5 FT AT 11PM EDT AND NOW AROUND 4FT.
THEREFORE THE SCA WAS DISCONTINUED.
OTRW A GENERALLY SSW 10-20 KT FLOW PREVAILS TODAY AND TONIGHT WITH
NO HEADLINE. MAYBE A BIT OF VSBY RESTRICTION IN FOG AND HAZE TIL
9 AM EDT AND POSSIBLY IN HAZE EARLY THURSDAY MORNING. WINDS WILL
PROBABLY TURN SSE ALONG THE COASTS FOR A TIME THIS AFTN BUT EVEN
THERE..THE WSW GRADIENT FLOW MAY PREVENT MUCH OF AN EAST OF SOUTH
TURN.
OUTLOOK...
WITH OFFSHORE HIGH PRESSURE INFLUENCING THE MID ATLANTIC REGION AND
OUR WATERS, SUB-SCA CONDITIONS ARE EXPECTED ON OUR WATERS FROM
THURSDAY THROUGH THE FIRST PART OF THE WEEKEND. WINDS THROUGH THIS
TIME FRAME WILL MAINLY BE OUT OF THE SOUTHWEST, WITH SEAS IN THE 3
TO 4 FOOT RANGE FOR OUR COASTAL WATERS AND 1 TO 3 FOOT SEAS IN
DELAWARE BAY. GOING INTO SUNDAY WITH HIGH PRESSURE DRIFTING FARTHER
EAST INTO THE CENTRAL ATLANTIC AND A COLD FRONT APPROACHING THE
REGION FROM THE WEST, WE EXPECT WIND GUSTS AND SEAS TO REACH SMALL
CRAFT ADVISORY LEVELS.
&&
.RIP CURRENTS...
TODAYS RIP CURRENT RISK IS AGAIN LOW BASED ON A 2 FT SWELL 9 SECOND
PERIOD AND RAN IT EITHER WITH A WIND 2115 OR 1812 WITH NEARLY
IDENTICAL LOW RISK RESULTS FOR BOTH NJ AND DE.
RIP CURRENT AWARENESS WEEK JUNE 2 THROUGH 8.
PSA`S WILL AIR ON KPHI NWR AND POST DAILY AROUND 545 AM. A SHORT
AWARENESS PRESS CONFERENCE IN SURF CITY - LBI, TUE JUNE 4 2PM FOR
THOSE MEDIA REPRESENTATIVES THAT ARE INTERESTED IN RAISING RIP
CURRENT AWARENESS AND CONDITIONS FAVORING UNGUARDED LIFE THREATENING
DANGER IN THE OCEAN SURF ZONE.
MORE ON THIS IN THE AFD NEXT MONDAY JUNE 3.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...DENSE FOG ADVISORY UNTIL 8 AM EDT THIS MORNING FOR PAZ054-055-
060>062-071-101>106.
NJ...DENSE FOG ADVISORY UNTIL 8 AM EDT THIS MORNING FOR NJZ007>010-
015.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KLINE
NEAR TERM...DRAG 624A
SHORT TERM...DRAG
LONG TERM...KLINE
AVIATION...DRAG/KLINE
MARINE...DRAG/KLINE
RIP CURRENTS...
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
738 AM EDT WED MAY 29 2013
.PREV DISCUSSION... /ISSUED 259 AM EDT WED MAY 29 2013/
SHORT TERM /TODAY THROUGH THURSDAY/...
SHORT TERM REMAINS QUIET FOR THE MOST PART...WITH RIDGING ALOFT AND
MOIST SOUTHERLY SURFACE FLOW AROUND THE WESTERN PERIPHERY OF A HIGH
IN THE ATLANTIC. A WEAKNESS IN THE FLOW ALOFT OVER THE BAHAMAS HAS
LED TO AN INCREASE IN CONVECTIVE ACTIVITY...AND SOME MOISTURE FROM
THIS SYSTEM IS PROGGED TO MOVE ACROSS FLORIDA TODAY AND INTO THE
DEEP SOUTH TONIGHT. NAM AND SREF BRING SOME PRECIP TO SOUTHWEST
ZONES...BUT ECMWF AND GFS KEEP THE AREA DRY. NAM GOES GANGBUSTERS
WITH THE CAPE...WITH OVER 1500 J/KG ACROSS SOUTHERN AND WESTERN
ZONES...WHEREAS ALL OTHER GUIDANCE KEEPS CAPE VALUES BELOW ABOUT 800
J/KG. HPC DOES PAINT SOME LIGHT QPF FROM APPROXIMATELY CARROLLTON TO
CORDELE AND POINTS SOUTH AND WEST...AND LOCAL WRF AND HRRR BOTH TRY
TO DEVELOP SOME POP-UP CONVECTION THIS AFTERNOON BUT KEEP MOST OF
THE CONVECTION IN ALABAMA. FOR NOW HOWEVER AM KEEPING ANY PRECIP
WORDING OUT WITH POPS REMAINING BELOW 15 PERCENT IN THOSE AREAS BUT
TRENDS WILL HAVE TO BE MONITORED. BIGGER IMPACT WILL BE FROM THE
STRATUS THAT IS EXPECTED TO MOVE IN OVERNIGHT AND EARLY THURSDAY...
WHICH WILL KEEP TEMPS UP A LITTLE HIGHER THAN THE PAST COUPLE OF
NIGHTS. MAX TEMPS THROUGH THE SHORT TERM WILL AGAIN BE ON THE WARM
SIDE BUT ONLY A COUPLE OF DEGREES ABOVE SEASONAL NORMALS.
TDP
LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
ECMWF AND GFS IN GOOD AGREEMENT INTO THE WEEKEND WITH DIFFERENCES
DEVELOPING AT THE EARLY PART OF NEXT WEEK. THE H5 RIDGE MAINTAINS
ITS HOLD OVER THE CWA THROUGH FRIDAY...THEN THE RIDGE BEGINS TO
BREAK DOWN AS THE UPPER TROUGH MOVES INTO THE MIDWEST. THIS WILL
DRIVE A COLD FRONT INTO THE TENNESSEE AND OHIO VALLEYS LATE SATURDAY
AND INTO SUNDAY AND MONDAY. THE ECMWF IS A LITTLE FASTER AND BRINGS
MOISTURE WITH THE FRONT INTO THE CWA LATE SATURDAY NIGHT. BOTH
MODELS PROG THE FRONT TO TAP INTO GULF MOISTURE SUNDAY BRINGING A
GOOD CHANCE OF PRECIP TO MUCH OF THE CWA. DIFFERENCES DEVELOP SUNDAY
NIGHT/MONDAY ON THE SPEED OF EXITING THE FRONT AND ASSOCIATED
MOISTURE. THE ECMWF PUSHES THE FRONT THROUGH BUT THE SOUTHEAST
CORNER OF THE CWA BY 12Z MONDAY WHILE THE GFS HOLDS THE FRONT BACK
CLEARING ONLY THE NORTHWEST PART OF THE CWA BY 12Z MON AND THEN
DEVELOPS A SECONDARY UPPER WAVE THAT INCREASES MOISTURE OVER MOST OF
THE CWA DURING THE DAY MONDAY. AT THIS POINT WILL MAINTAIN HIGH POPS
SUNDAY AND MONDAY AND BRING LOW OR NO POPS ON TUESDAY.
17
&&
.AVIATION...
12Z UPDATE...
LARGE AREA OF LOW MVFR CIGS DID MANAGE TO DEVELOP NEAR MCN AND
SPREAD NORTH OVER THE PAST FEW HOURS...JUST NOW REACHING TO ATL.
WILL CARRY THIS FOR ANOTHER HOUR OR SO...OTHERWISE...VFR CIGS
THROUGH THE AFTERNOON AND EVENING WITH SE WINDS GENERALLY 5-10KT.
INCREASING MOISTURE THURSDAY MORNING SHOULD BRING MVFR TO
POTENTIALLY IFR CIGS EVERYWHERE BETWEEN 08-10Z.
//ATL CONFIDENCE...12Z UPDATE...
MEDIUM ON TIMING OF CIGS THIS MORNING AND TOMORROW MORNING.
HIGH ON ALL OTHER ELEMENTS.
TDP
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 85 64 85 66 / 5 5 5 5
ATLANTA 84 67 83 66 / 5 5 5 5
BLAIRSVILLE 81 60 81 63 / 0 5 5 5
CARTERSVILLE 85 65 84 66 / 5 5 5 5
COLUMBUS 88 69 87 69 / 5 10 10 5
GAINESVILLE 82 65 81 66 / 5 5 5 5
MACON 88 66 87 67 / 5 5 5 0
ROME 87 65 85 66 / 5 5 10 10
PEACHTREE CITY 85 65 84 66 / 5 5 5 5
VIDALIA 88 69 89 69 / 5 5 5 0
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS POCATELLO ID
835 AM MDT WED MAY 29 2013
.UPDATE...SHOWERS LINGER ALONG EASTERN HIGHLANDS THIS MORNING PER
RADAR IMAGERY AND SURFACE OBSERVATIONS. REMAINDER OF EASTERN IDAHO
DRY BUT NEXT BAND OF SHOWERS ALREADY INTO WESTERN IDAHO AHEAD OF
UPPER TROUGH MOVING THROUGH THE PACNW. HRRR REDEVELOPS SHOWERS
OVER THE NORTHEAST CORNER OF THE REGION AND ALONG THE WYOMING
BORDER THROUGH THE REMAINDER OF THE MORNING. THIS MAY BE SOMEWHAT
OVERDONE WITH EARLY CLOUD COVER AND REGION OF DRIER MID LEVELS PER
WV IMAGERY BUT OROGRAPHICS AND MOIST LOW LEVELS MAY BE ENOUGH TO
OVERCOME. BAND OF PRECIP IN WESTERN IDAHO LOOKS TO REACH WESTERN
EDGES OF THE FORECAST AREA BY 18Z...SPREADING RAPIDLY ACROSS THE
REGION THROUGH THIS AFTERNOON AND EARLY EVENING. MODELS PAINT
LEAST PRECIP OVER THE SNAKE PLAIN THUS KEPT FOCUS OVER HIGHER
ELEVATIONS. MADE A FEW ADJUSTMENTS TO POP/QPF/WX GRIDS FOR TODAY
BASED ON SAT AND RADAR TRENDS. IN ADDITION...SURFACE GRADIENT
STILL ENOUGH AND GUIDANCE STILL SUPPORTIVE OF WINDS FAVORABLE FOR
CHOP ON THE RESERVOIR SO WILL LEAVE CURRENT LAKE WIND ADVISORY IN
PLACE. DMH
&&
.PREV DISCUSSION... /ISSUED 313 AM MDT WED MAY 29 2013/
DISCUSSION...UPPER TROUGH CURRENTLY OVER THE WA/OR COAST MAKING ITS
WAY INLAND. THIS TROUGH SHOULD IMPACT SOUTHEAST IDAHO LATER TODAY.
MODELS INDICATE SOME INSTABILITY WILL BE OVER THE REGION LATER THIS
AFTERNOON WITH LI VALUES GENERALLY AROUND 0C TO -1C. STABILITY COULD
BE LOWER IF WE MANAGE TO SEE SUFFICIENT CLEARING THIS
AFTERNOON...AND THE NAM AND LOCAL WRF RUNS HINT AT THAT POSSIBILITY.
HAVE LEFT SLIGHT CHANCE TS MENTION FOR THE AFTERNOON/EVENING. BEGAN
TRIMMING POPS AFTER THE UPPER TROUGH PASSES AS UPPER RIDGING BUILDS
BACK IN TO THE WEST. ALSO TODAY...WINDS WILL BE STRONG ENOUGH TO
WARRANT A LAKE WIND ADVISORY FOR AMERICAN FALLS RESERVOIR. SHOWERS
MAY BUILD BACK INTO THE UPPER SNAKE HIGHLANDS THURSDAY WITH ENERGY
ROTATING AROUND AN WEAK UPPER LOW OVER EASTERN WY/MT. THE WEEKEND
SHOULD BE FAIRLY DRY WITH UPPER RIDGING MOVING ACROSS IDAHO...BUT
MODELS CONTINUE TO DIG AN UPPER TROUGH OVER THE PAC NORTHWEST ON
SUNDAY AND MONDAY. GFS/ECMWF KEEP MOST OF THE QPF WITH THE TROUGH
FURTHER TO THE NORTH WHERE THE SOUTHERN END OF THE TROUGH DOES NOT
HAVE VERY MUCH MOISTURE TO WORK WITH. HINSBERGER
AVIATION...LOW PRESSURE DISTURBANCE NEAR THE OREGON COAST THIS
MORNING EXPECTED TO CROSS SOUTHEAST IDAHO THIS AFTERNOON. ISOLATED
THUNDERSTORMS POSSIBLE AT TAF SITES BETWEEN 19-01Z. OUTFLOW GUSTS UP
TO 45 MPH AND SMALL HAIL POSSIBLE. NAM12 SURFACE FRONT DEPICTION
TRAILS WET-EAST ORIENTATION THROUGH ABOUT SALMON IDAHO...THEREFORE
BREEZY WSW WINDS OF 15-20 KTS EXPECTED IN THE SNAKE PLAIN INCLUDING
KBYI...KIDA...AND KPIH BUT NO SIGNIFICANT FRONTAL WIND SHIFT.
THURSDAY AFTERNOON...WEAK HIGH PRESSURE RIDGING TO THE WEST RESULTS
IN AFTERNOON CONVECTION SHIFTING FURTHER NORTH...AT LEAST FOR KBYI
AND KPIH. THERE WILL BE A SLIGHT CHANCE OF SHOWERS NEAR KSUN AND
KIDA. RS
FIRE WEATHER...A LOW PRESSURE DISTURBANCE NEAR THE OREGON COAST
THIS MORNING WILL CROSS SOUTHEAST IDAHO THIS AFTERNOON. SCATTERED
RAIN SHOWERS WITH ISOLATED THUNDERSTORMS THIS AFTERNOON EXPECTED
ACROSS THE DISTRICT BETWEEN NOON AND ABOUT 1900 HOURS. THE
ASSOCIATED FRONTAL BOUNDARY WILL BE ORIENTED WEST TO EAST THROUGH
THE SALMON AREA. OVER THE CENTRAL MOUNTAINS A SUBTLE SHIFT IN WINDS
FROM SOUTHWEST TO WEST IS EXPECTED NOON TO 1500 HOURS. IN THE SNAKE
PLAIN WEST-SOUTHWEST WINDS OF 15 TO 25 MPH WILL SHOW LITTLE OR NO
WIND SHIFT. WINDS IN THE SNAKE PLAIN WILL BE BREEZY OVERNIGHT AND
THROUGH THE DAY THURSDAY. RELATIVE HUMIDITY IN THE LOWER VALLEYS
WILL BE 30 TO 40 PERCENT TODAY AND TREND DOWNWARD TO THE LOWER 20S
BY FRIDAY AFTERNOON. RS
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
LAKE WIND ADVISORY FROM NOON TODAY TO 9 PM MDT THIS EVENING
IDZ021.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
553 AM MDT WED MAY 29 2013
.SHORT TERM...(TODAY THROUGH THURSDAY NIGHT)
ISSUED AT 417 AM MDT WED MAY 29 2013
MAIN FORECAST CONCERN IS SIGNIFICANT WEATHER EXPECTED THROUGH
TONIGHT. SATELLITE SHOWING A PROGRESSIVE FLOW FROM THE PACIFIC INTO
NORTH AMERICA. MAIN FEATURE OF INTEREST IS STRONG AND DEVELOPING
UPPER SYSTEM APPROACHING FROM THE WEST. WARM FRONT NORTH OF THE
AREA.
MODELS INITIALIZED FINE AT JET LEVEL BUT WOULD HAVE TO GIVE A SLIGHT
EDGE TO THE GFS AND CANADIAN ON THE JET SEGMENT BEHIND INCOMING
TROUGH. EVEN CLOSE TO THE EVENT MODELS STILL HAVE TROUBLE WITH
INCOMING SHORTWAVE TROUGH. IT HAS BEEN REORGANIZING/DEVELOPING THIS
EVENING AND LOOKS LIKE IT WILL CONTINUE TO DO SO. THROUGH SATELLITE
AND UPPER AIR ANALYSIS...THE CANADIAN IS DOING SLIGHTLY BETTER THAN
THE GFS. EVOLVING SURFACE PATTERN GOING ON RIGHT NOW. RUC IS
CATCHING THINGS WELL. THEN THE CANADIAN AND ECMWF ARE NEXT IN LINE
AND MATCH UP WITH IT. THE CANADIAN...GFS AND ECMWF WERE DOING THE
BEST ON THE LOW LEVEL THERMAL FIELD.
TODAY/TONIGHT...AS HAS BEEN THE CASE THE LAST FEW DAYS THE MODELS
DEVELOP A MID/UPPER JET SEGMENT OVER THE CENTRAL AND EASTERN PORTION
OF THE FORECAST BY 18Z WITH THAT AREA BEING UNDER THE LEFT FRONT
QUADRANT. THE ECMWF HOLDS ONTO THIS OVER THE FORECAST AREA LONGER...
INTO THE EVENING...THAN THE OTHER MODELS. AS THE NIGHT HAS PROGRESSED
THE MODELS HAVE BEEN SLOWING THE ARRIVAL OF THE FRONT. FRONT LOOKS
TO BE NEAR OR JUST EAST OF THE COLORADO BORDER BY 00Z. IN ADDITION
TO THE JET STRONG MID LEVEL LIFT IS AROUND AS WELL. MODELS SHOWING
LITTLE TO NO CAP MY THE MIDDLE OF THE DAY. MAIN QUESTION WILL BE
HOW MUCH MOISTURE WILL THIS ALL HAVE TO WORK WITH. THAT MAY SLOW
DOWN THE ONSET OF THE PRECIPITATION BUT AM THINKING THE LIFT AND
INSTABILITY MAY OVERCOME THIS.
SO HAVE INSERTED POPS BEGINNING AT 15Z AND THEN RAMP THEM QUICKLY
IN THE AFTERNOON. THERE WILL BE A TIGHT GRADIENT OF POPS. IF THERE
IS ANY SLOWING...POPS WILL NEED TO BE PULLED BACK FURTHER WEST. AT
THIS TIME THE EASTERN HALF TO TWO THIRDS THROUGH TONIGHT WILL HAVE
A VERY GOOD CHANCE OF SEEING RAIN/THUNDERSTORMS. PARAMETERS POINT TO
THESE THUNDERSTORMS BECOMING SEVERE AND HAVE INSERTED SEVERE
WORDING FOR THIS AFTERNOON AND TONIGHT. IN ADDITION MODEL QPFS ARE
RATHER HIGH IN THE EASTERN HALF TO TWO THIRDS. NAM/GFS/SREF
PRECIPITABLE WATER VALUES ARE 1 TO 1.25 INCHES. DAY SHIFT MADE A
GOOD POINT WITH THE STORM MOTIONS IN ADVANCE OF THE FRONT
SUPPORTING TRAINING OF THE CELLS. SREF HAS A 30 PERCENT PROBABILITY
OF 1 INCH OF RAINFALL IN THE EAST. SO WENT AHEAD AND ADDED LOCALLY
HEAVY RAINFALL TO THE ABOVE MENTIONED AREA.
THE MOST WIDESPREAD ACTIVITY LOOKS TO END NEAR OR SHORTLY AFTER
06Z. BUT INCOMING JET AND ANOTHER SHORTWAVE TROUGH APPROACH FROM THE
WEST LATE IN THE NIGHT. SO SOME KIND OF CHANCE REMAINS THROUGH THE
NIGHT. NOT SURE ABOUT THE MAXES BUT MESOSCALE MODELS...ESPECIALLY
THE RUC...HAVE MAXES WARMER THAN WHAT I HAVE IN THERE. DID NUDGE
MAXES UP A LITTLE SINCE WARMER MAXES...IF NOT A LOT OF CLOUD COVER...
MAKE SENSE WITH THE SLOWER ARRIVAL OF THE FRONT.
THURSDAY/THURSDAY NIGHT...MODELS TAKE THE LEFT FRONT QUADRANT ACROSS
THE AREA DURING THE AFTERNOON AND EARLY EVENING WITH THE JET SEGMENT
NEAR OR OVER THE NORTHERN PORTION OF THE AREA THROUGH THE REST OF THE
NIGHT. THERE IS ALSO A RATHER STRONG PV ANOMALY WITH THIS. AIR MASS
IS UNSTABLE WITH GOOD LAPSE RATES. SO KEPT A LOW CHANCE OF
THUNDERSTORMS AROUND INTO THE EVENING. LOOK TO HAVE BREEZY OR NEAR
BREEZY WEST TO NORTHWEST WINDS. DEPENDING ON THE AMOUNT OF CLOUD
COVER AND PRECIPITATION...THESE WINDS MAY HELP TEMPERATURES CLIMB A
LITTLE MORE THAN ANTICIPATED. WINDS DIE OFF DURING THE FIRST PART OF
THE NIGHT AND THEN PICK A LITTLE MORE LATER. DEWPOINTS WILL BE LOWER.
COULD BE RATHER COOL NIGHT.
FRIDAY/FRIDAY NIGHT...JET STARTS OFF OVER THE NORTHERN PORTION OF
THE AREA AND THEN SOUTH OF THE AREA DURING THE DAY. MODELS WANT TO
GENERATE SOME LIGHT QPF. HOWEVER...THERE IS A RATHER DEEP DRY LAYER
SO KEPT IT DRY AT THIS TIME. IT MAY BE POSSIBLE THAT COULD SEE
SPRINKLES. ONCE AGAIN LOOK TO HAVE BREEZY OR NEAR BREEZY WEST ACROSS
THE AREA. MODELS COOL OFF TEMPERATURES FROM THE PREVIOUS DAY BUT
THOSE WINDS MAY HELP WARM TEMPERATURES A LITTLE MORE. WINDS DIE OFF
MORE THAN THE PREVIOUS NIGHT AND LOOK TO ANOTHER RATHER COOL NIGHT.
.LONG TERM...(SATURDAY THROUGH TUESDAY)
ISSUED AT 417 AM MDT WED MAY 29 2013
EXTENDED RANGE LOOKS TO BE SEASONABLE FOR THE BEGINNING OF JUNE.
PERIOD BEGINS ON SATURDAY WITH THE UPPER LOW THAT WILL BE OVER THE
CENTRAL PLAINS LATE THIS WEEK MOVING EAST INTO THE MIDWEST WHILE A
LONGWAVE RIDGE BUILDS ACROSS THE HIGH PLAINS BEHIND IT ON SUNDAY.
SOUTHERLY FLOW AT 850MB WILL BRING WARMER AIR UP FOR LATE IN THE
WEEKEND THROUGH MID-NEXT WEEK. ON MONDAY A SURFACE TROUGH/DRY LINE
WILL SET UP ALONG OR NEAR THE KANSAS-COLORADO BORDER. AT THE SAME
TIME A NUMBER OF WEAK SHORTWAVE TROUGHS MOVE UP FROM THE SOUTHWEST
TO NORTHEAST ACROSS THE CWA...WHICH ALONG WITH DIURNAL HEATING COULD
SET OFF SOME SHOWERS/STORMS ON MONDAY AND TUESDAY. TUESDAY WILL HAVE
HIGHS WELL ABOVE NORMAL...WITH THE GFS AND GEM PROJECTING 850MB
TEMPS IN EXCESS OF 30C. ECMWF IS A BIT MORE CONSERVATIVE...BUT EVEN
SO BELIEVE HIGHS ON TUESDAY WILL BE WELL INTO THE 90S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 548 AM MDT WED MAY 29 2013
SIGNIFICANT SEVERE WEATHER EVENT TO DEVELOP ACROSS THE AREA THIS
AFTERNOON INTO THIS EVENING. IN GENERAL KMCK WILL HAVE THE GREATEST
THREAT OF HAVING MVFR OR LOWER CONDITIONS. UNTIL THEN GUSTY
SOUTHERLY WINDS WILL OCCUR AT BOTH SITES. FOR KGLD THUNDERSTORM
INITIATION WILL BE VERY NEAR TO THIS SITE. SO AT THIS TIME JUST
CHOSE TO PUT VCTS IN THE TAF. FOR KMCK...FELT MORE COMFORTABLE IN
PUTTING IN SUB VFR CONDITIONS LATER THIS AFTERNOON. HOWEVER...SOME
MODEL OUTPUT BRINGS IN THUNDERSTORMS SOONER THAN THAT. LATER
FORECASTS WILL HAVE TO FINE TUNE THIS. EVEN THOUGH NO VISIBILITY
RESTRICTIONS WERE PUT INTO THE KMCK TAF...VERY HEAVY RAINFALL
COULD DRAMATICALLY LOWER THE VISIBILITY. THAT WILL ALSO NEED TO BE
FINE TUNED AS WELL.
&&
.FIRE WEATHER...
ISSUED AT 417 AM MDT WED MAY 29 2013
FOR TODAY...MAY BE A BRIEF PERIOD OF LOW RELATIVE HUMIDITIES AND
WINDS. BUT THERE IS A HIGH DEGREE OF UNCERTAINTY OF BOUNDARY
POSITIONS. PLUS DO NOT EXPECT PRECIPITATION TO DEVELOP IN THE
AFTERNOON.
FOR THURSDAY...IF CURRENT FORECAST PANS OUT...MOST OF THE FORECAST
AREA WILL RECEIVE RAINFALL FROM TODAYS SYSTEM. EASTERN COLORADO
WILL GET THE LEAST WITH THE EASTERN HALF TO TWO THIRDS GETTING THE
MOST. THE REASON THIS IS MENTIONED IS BECAUSE WIND SPEEDS AND
RELATIVE HUMIDITIES COULD REACH CRITICAL RED FLAG CRITERIA OVER THE
WESTERN HALF. PLUS ADDITIONAL PRECIPITATION IS EXPECTED ON
THURSDAY. SO AT THIS TIME AM ANTICIPATING NO FIRE WEATHER HIGHLIGHTS
WITH EASTERN COLORADO HAVE THE BEST CHANCE.
FOR FRIDAY...LOWER RELATIVE HUMIDITIES AND GUSTY WEST TO NORTHWEST
WINDS WILL SPREAD OVER MORE OF THE FORECAST AREA THAN THE PREVIOUS
DAY. AGAIN WILL HAVE TO SEE HOW CURRENT PRECIPITATION FORECAST
WORKS OUT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...JJM
AVIATION...BULLER
FIRE WEATHER...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
417 AM MDT WED MAY 29 2013
.SHORT TERM...(TODAY THROUGH THURSDAY NIGHT)
ISSUED AT 417 AM MDT WED MAY 29 2013
MAIN FORECAST CONCERN IS SIGNIFICANT WEATHER EXPECTED THROUGH
TONIGHT. SATELLITE SHOWING A PROGRESSIVE FLOW FROM THE PACIFIC INTO
NORTH AMERICA. MAIN FEATURE OF INTEREST IS STRONG AND DEVELOPING
UPPER SYSTEM APPROACHING FROM THE WEST. WARM FRONT NORTH OF THE
AREA.
MODELS INITIALIZED FINE AT JET LEVEL BUT WOULD HAVE TO GIVE A SLIGHT
EDGE TO THE GFS AND CANADIAN ON THE JET SEGMENT BEHIND INCOMING
TROUGH. EVEN CLOSE TO THE EVENT MODELS STILL HAVE TROUBLE WITH
INCOMING SHORTWAVE TROUGH. IT HAS BEEN REORGANIZING/DEVELOPING THIS
EVENING AND LOOKS LIKE IT WILL CONTINUE TO DO SO. THROUGH SATELLITE
AND UPPER AIR ANALYSIS...THE CANADIAN IS DOING SLIGHTLY BETTER THAN
THE GFS. EVOLVING SURFACE PATTERN GOING ON RIGHT NOW. RUC IS
CATCHING THINGS WELL. THEN THE CANADIAN AND ECMWF ARE NEXT IN LINE
AND MATCH UP WITH IT. THE CANADIAN...GFS AND ECMWF WERE DOING THE
BEST ON THE LOW LEVEL THERMAL FIELD.
TODAY/TONIGHT...AS HAS BEEN THE CASE THE LAST FEW DAYS THE MODELS
DEVELOP A MID/UPPER JET SEGMENT OVER THE CENTRAL AND EASTERN PORTION
OF THE FORECAST BY 18Z WITH THAT AREA BEING UNDER THE LEFT FRONT
QUADRANT. THE ECMWF HOLDS ONTO THIS OVER THE FORECAST AREA LONGER...
INTO THE EVENING...THAN THE OTHER MODELS. AS THE NIGHT HAS PROGRESSED
THE MODELS HAVE BEEN SLOWING THE ARRIVAL OF THE FRONT. FRONT LOOKS
TO BE NEAR OR JUST EAST OF THE COLORADO BORDER BY 00Z. IN ADDITION
TO THE JET STRONG MID LEVEL LIFT IS AROUND AS WELL. MODELS SHOWING
LITTLE TO NO CAP MY THE MIDDLE OF THE DAY. MAIN QUESTION WILL BE
HOW MUCH MOISTURE WILL THIS ALL HAVE TO WORK WITH. THAT MAY SLOW
DOWN THE ONSET OF THE PRECIPITATION BUT AM THINKING THE LIFT AND
INSTABILITY MAY OVERCOME THIS.
SO HAVE INSERTED POPS BEGINNING AT 15Z AND THEN RAMP THEM QUICKLY
IN THE AFTERNOON. THERE WILL BE A TIGHT GRADIENT OF POPS. IF THERE
IS ANY SLOWING...POPS WILL NEED TO BE PULLED BACK FURTHER WEST. AT
THIS TIME THE EASTERN HALF TO TWO THIRDS THROUGH TONIGHT WILL HAVE
A VERY GOOD CHANCE OF SEEING RAIN/THUNDERSTORMS. PARAMETERS POINT TO
THESE THUNDERSTORMS BECOMING SEVERE AND HAVE INSERTED SEVERE
WORDING FOR THIS AFTERNOON AND TONIGHT. IN ADDITION MODEL QPFS ARE
RATHER HIGH IN THE EASTERN HALF TO TWO THIRDS. NAM/GFS/SREF
PRECIPITABLE WATER VALUES ARE 1 TO 1.25 INCHES. DAY SHIFT MADE A
GOOD POINT WITH THE STORM MOTIONS IN ADVANCE OF THE FRONT
SUPPORTING TRAINING OF THE CELLS. SREF HAS A 30 PERCENT PROBABILITY
OF 1 INCH OF RAINFALL IN THE EAST. SO WENT AHEAD AND ADDED LOCALLY
HEAVY RAINFALL TO THE ABOVE MENTIONED AREA.
THE MOST WIDESPREAD ACTIVITY LOOKS TO END NEAR OR SHORTLY AFTER
06Z. BUT INCOMING JET AND ANOTHER SHORTWAVE TROUGH APPROACH FROM THE
WEST LATE IN THE NIGHT. SO SOME KIND OF CHANCE REMAINS THROUGH THE
NIGHT. NOT SURE ABOUT THE MAXES BUT MESOSCALE MODELS...ESPECIALLY
THE RUC...HAVE MAXES WARMER THAN WHAT I HAVE IN THERE. DID NUDGE
MAXES UP A LITTLE SINCE WARMER MAXES...IF NOT A LOT OF CLOUD COVER...
MAKE SENSE WITH THE SLOWER ARRIVAL OF THE FRONT.
THURSDAY/THURSDAY NIGHT...MODELS TAKE THE LEFT FRONT QUADRANT ACROSS
THE AREA DURING THE AFTERNOON AND EARLY EVENING WITH THE JET SEGMENT
NEAR OR OVER THE NORTHERN PORTION OF THE AREA THROUGH THE REST OF THE
NIGHT. THERE IS ALSO A RATHER STRONG PV ANOMALY WITH THIS. AIR MASS
IS UNSTABLE WITH GOOD LAPSE RATES. SO KEPT A LOW CHANCE OF
THUNDERSTORMS AROUND INTO THE EVENING. LOOK TO HAVE BREEZY OR NEAR
BREEZY WEST TO NORTHWEST WINDS. DEPENDING ON THE AMOUNT OF CLOUD
COVER AND PRECIPITATION...THESE WINDS MAY HELP TEMPERATURES CLIMB A
LITTLE MORE THAN ANTICIPATED. WINDS DIE OFF DURING THE FIRST PART OF
THE NIGHT AND THEN PICK A LITTLE MORE LATER. DEWPOINTS WILL BE LOWER.
COULD BE RATHER COOL NIGHT.
FRIDAY/FRIDAY NIGHT...JET STARTS OFF OVER THE NORTHERN PORTION OF
THE AREA AND THEN SOUTH OF THE AREA DURING THE DAY. MODELS WANT TO
GENERATE SOME LIGHT QPF. HOWEVER...THERE IS A RATHER DEEP DRY LAYER
SO KEPT IT DRY AT THIS TIME. IT MAY BE POSSIBLE THAT COULD SEE
SPRINKLES. ONCE AGAIN LOOK TO HAVE BREEZY OR NEAR BREEZY WEST ACROSS
THE AREA. MODELS COOL OFF TEMPERATURES FROM THE PREVIOUS DAY BUT
THOSE WINDS MAY HELP WARM TEMPERATURES A LITTLE MORE. WINDS DIE OFF
MORE THAN THE PREVIOUS NIGHT AND LOOK TO ANOTHER RATHER COOL NIGHT.
.LONG TERM...(SATURDAY THROUGH TUESDAY)
ISSUED AT 417 AM MDT WED MAY 29 2013
EXTENDED RANGE LOOKS TO BE SEASONABLE FOR THE BEGINNING OF JUNE.
PERIOD BEGINS ON SATURDAY WITH THE UPPER LOW THAT WILL BE OVER THE
CENTRAL PLAINS LATE THIS WEEK MOVING EAST INTO THE MIDWEST WHILE A
LONGWAVE RIDGE BUILDS ACROSS THE HIGH PLAINS BEHIND IT ON SUNDAY.
SOUTHERLY FLOW AT 850MB WILL BRING WARMER AIR UP FOR LATE IN THE
WEEKEND THROUGH MID-NEXT WEEK. ON MONDAY A SURFACE TROUGH/DRY LINE
WILL SET UP ALONG OR NEAR THE KANSAS-COLORADO BORDER. AT THE SAME
TIME A NUMBER OF WEAK SHORTWAVE TROUGHS MOVE UP FROM THE SOUTHWEST
TO NORTHEAST ACROSS THE CWA...WHICH ALONG WITH DIURNAL HEATING COULD
SET OFF SOME SHOWERS/STORMS ON MONDAY AND TUESDAY. TUESDAY WILL HAVE
HIGHS WELL ABOVE NORMAL...WITH THE GFS AND GEM PROJECTING 850MB
TEMPS IN EXCESS OF 30C. ECMWF IS A BIT MORE CONSERVATIVE...BUT EVEN
SO BELIEVE HIGHS ON TUESDAY WILL BE WELL INTO THE 90S.
&&
.AVIATION....(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1113 PM MDT TUE MAY 28 2013
THE POTENTIAL FOR WIND SHEAR ALONG WITH OCCASIONALLY GUSTY SURFACE
WINDS EXISTS AS A STRONG LOW LEVEL SOUTHEASTERLY JET MOVES INTO
WEST CENTRAL KANSAS AND EAST CENTRAL COLORADO AS A WARM FRONT
PUSHES NORTH THROUGH THE CENTRAL HIGH PLAINS REGION. THIS SHOULD
AFFECT THE GLD TAF MORE THAN THE MCK TAF...BUT HAVE NOT INCLUDED
WIND SHEAR IN THE GLD TAF AT THIS TIME AS IT APPEARS THE SURFACE
WINDS MAY NOT COMPLETELY DECOUPLE FROM THE LOW LEVEL WINDS. THE
PRESSURE GRADIENT IS WEAKER AT MCK...SO DO NOT EXPECT TO SEE THE
SAME KIND OF WINDS THERE.
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD AT GLD WITH
SCATTERED THUNDERSTORMS DEVELOPING AFTER 18Z WEDNESDAY THAT WILL
MOVE ACROSS THE AREA BEFORE DISSIPATING AFTER 02Z.
CONDITIONS WILL INITIALLY BE VFR AT MCK...BUT ARE EXPECTED TO
BECOME MVFR BETWEEN 11Z-15Z DUE TO GREATER AVAILABLE LOW LEVEL
MOISTURE EXPECTED TO PRODUCE LOWER CLOUDS. VFR CONDITIONS WILL
RETURN AS LOWER CLOUDS DISSIPATE AFTER 15Z WITH SCATTERED
THUNDERSTORMS EXPECTED TO DEVELOP AFTER 20Z...CONTINUING THROUGH
ABOUT 04Z.
&&
.FIRE WEATHER...
ISSUED AT 417 AM MDT WED MAY 29 2013
FOR TODAY...MAY BE A BRIEF PERIOD OF LOW RELATIVE HUMIDITIES AND
WINDS. BUT THERE IS A HIGH DEGREE OF UNCERTAINTY OF BOUNDARY
POSITIONS. PLUS DO NOT EXPECT PRECIPITATION TO DEVELOP IN THE
AFTERNOON.
FOR THURSDAY...IF CURRENT FORECAST PANS OUT...MOST OF THE FORECAST
AREA WILL RECEIVE RAINFALL FROM TODAYS SYSTEM. EASTERN COLORADO
WILL GET THE LEAST WITH THE EASTERN HALF TO TWO THIRDS GETTING THE
MOST. THE REASON THIS IS MENTIONED IS BECAUSE WIND SPEEDS AND
RELATIVE HUMIDITIES COULD REACH CRITICAL RED FLAG CRITERIA OVER THE
WESTERN HALF. PLUS ADDITIONAL PRECIPITATION IS EXPECTED ON
THURSDAY. SO AT THIS TIME AM ANTICIPATING NO FIRE WEATHER HIGHLIGHTS
WITH EASTERN COLORADO HAVE THE BEST CHANCE.
FOR FRIDAY...LOWER RELATIVE HUMIDITIES AND GUSTY WEST TO NORTHWEST
WINDS WILL SPREAD OVER MORE OF THE FORECAST AREA THAN THE PREVIOUS
DAY. AGAIN WILL HAVE TO SEE HOW CURRENT PRECIPITATION FORECAST
WORKS OUT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...JJM
AVIATION...LOCKHART
FIRE WEATHER...BULLER
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
559 AM CDT WED MAY 29 2013
.UPDATE...
12Z AVIATION DISCUSSION ADDED BELOW.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 400 AM CDT WED MAY 29 2013
A VERY VOLATILE WATER VAPOR IMAGE AND H5 PATTERN IS IN PLACE THIS
MORNING AS A NEGATIVELY TILTED TROUGH SITS FROM NEAR YELLOW STONE
SOUTHEAST TO THE BIG BEND REGION OF TEXAS. CONVECTION ACROSS THE
PLAINS YESTERDAY AND OVERNIGHT HAS LEFT MULTIPLE SHORT WAVES/MCVS
LITTERED ACROSS NATIONS MIDSECTION. DURING THE DAY...THE MAIN TROUGH
WILL MIGRATE E/NE ACROSS THE PLAINS...AND BY THE END OF THE PERIOD
THE TROUGH WILL STRETCH FROM A DEVELOPING CLOSED LOW OVER THE BLACK
HILLS SOUTHEAST TOWARD NE TEXAS.
AT 330 AM...THE WARM WAS JUST PASSING THROUGH FORT DODGE IN IOWA AND
HAS ACTUALLY BEGUN TO PICK UP SOME MOMENTUM TOWARD THE NORTH IN THE
LAST FEW HOURS. BASED ON THE RAP...THIS BOUNDARY WILL BE NEAR I-90
AT 15Z...BY 18Z IT SHOULD BE WORKING ITS WAY THROUGH THE TWIN CITIES
BEFORE BECOMING STATIONARY AT 00Z FROM A SFC LOW OVER NORTH CENTRAL
NEB...NORTHEAST THROUGH ABERDEEN AND UP TOWARD LAKE OF THE WOODS.
FOR THIS FORECAST...FAVORED A NAM/ECMWF BLEND FOR HANDLING OF LARGE
SCALE FEATURES SUCH AS SHORTWAVES AND THE LLJ...WHILE A BLEND OF THE
HI-RES CAMS WERE USED TO TRY AND ADD DETAIL TO THE POP FORECAST.
BASED ON THAT...WHAT FOLLOWS IS THE CURRENT THINKING IS OF 330 AM
FOR WHAT WILL HAPPEN TODAY.
FOR THE WARM FRONT COMING NORTH...IS LOOKING LIKE CONVECTIVE
ACTIVITY WILL BE SCATTERED IN NATURE...AS H85 LLJ IS ACTUALLY
SOMEWHAT DIFFLUENT OVER MN...WITH ONE BRANCH SPLITTING OF FROM IOWA
INTO SODAK...WITH THE REST OF THE JET FANNING OUT TOWARD THE NE
ACROSS MN INTO WI. THE HRRR AND OTHER CAMS ALONG WITH THE RAP IS
SHOWING A BATCH OF ELEVATED SHOWERS AND STORMS DEVELOPING EARLY THIS
MORNING NORTH OF THE BOUNDARY AND HEADING TOWARD SE MN BY THE EARLY
AFTERNOON. THIS SEEMS TO BE IN RESPONSE TO A SHORTWAVE NOTED ON
WATER VAPOR CURRENTLY WEST OF OMAHA THAT THE RAP DRAGS NE TOWARD SE
MN THROUGH THE MORNING. THE HRRR IS BY FAR THE MOST AGGRESSIVE WITH
THIS CONVECTION AT THE MOMENT...BUT OUTSIDE OF SOME POTENTIAL FOR
HAIL...THE SEVERE THREAT LOOKS LIMITED WITH THIS BATCH OF
CONVECTION...IF IT DOES FORM.
FOR THE SEVERE THREAT...ATTENTION REALLY TURNS TO ERN SODAK/WRN MN
THIS AFTERNOON. WITH THE NAM/ECMWF SHOWING THE LLJ ANGLING BACK NW
INTO SODAK IN RESPONSE TO HEIGHT FALLS ALOFT...THIS SHOULD LEAD TO
THE INITIATION OF MORE SURFACE BASED CONVECTION SOMEWHERE NEAR THE
RETREATING WARM FRONT IN ERN SODAK/WRN MN. FORECAST SOUNDINGS FROM
THE RAP/NAM SHOW ATMO REMAINING CAPPED ACROSS WRN MN UNTIL ABOUT
21Z...AT WHICH POINT YOU ARE DEALING WITH AROUND 1500 J/KG OF SBCAPE
IN A WEAKLY CAPPED...STRONGLY SHEARED /ESPECIALLY IN THE LOWEST 3
KM/ ENVIRONMENT. NMM/ARW BASED CAMS SHOW LITTLE CONVECTION
DEVELOPING THROUGH 21Z...BUT QUICKLY GENERATE CONVECTION AFTER
21Z...SO WAITED TO INTRODUCE ANY LIKELY POPS UNTIL 21Z. SEEING TWO
CAMPS IN THE CAMS FOR HOW CONVECTION DEVELOPS THIS AFTERNOON...WITH
THE ARW AND NSSL-WRF GENERATING STORMS OVER WRN MN...WHILE THE NMM
AND SPCWRF GENERATE CONVECTION OVER ERN SODAK. THIS IDEA FOR
ACTIVITY STARTING OUT WEST THIS AFTERNOON IS FURTHER SUPPORTED BY
THE SPC SSEO...WHICH SHOWS NEIGHBORHOOD PROBABILITIES FOR UPDRAFT
HELICITY AND UPDRAFT STRENGTH BEING MAXIMIZED OVER ERN SODAK INTO
WRN MN...WITH VERY LITTLE ACTIVITY BEING NOTED FROM SRN INTO ERN MN
AND WRN WI THIS AFTERNOON. GIVEN DEGREE OF LOW LEVEL SHEAR...THERE
WILL BE THE THREAT FOR TORNADIC ACTIVITY WHILE THE STORMS AREA
DISCRETE...BUT DO EXPECT STORMS THIS AFTERNOON TO GROW
UPSCALE...WITH A HAIL/WIND THREAT CONTINUING INTO THE NIGHT.
FOR TONIGHT...WHAT HAPPENS WITH CONVECTION THIS AFTERNOON WILL PLAY
A LARGE ROLE IN WHAT HAPPENS TONIGHT. WITHIN THE CAMS...WE ARE AGAIN
LOOKING AT TWO CAMPS. THE NMM AND SPCWRF DO NOT BRING THE DAKOTA
CONVECTION INTO MN...WHILE SENDING ANOTHER MCS RACING ACROSS
IOWA...KEEPING MUCH OF THE MPX CWA DRY. THE ARW AND NSSL-WRF CONGEAL
THE AFTERNOON CELLS IN THE WEST INTO A LINE...AND TRACK THAT COMPLEX
OF STORMS EAST ACROSS THE STATE THROUGH THE NIGHT. GIVEN EXPECTED
EVOLUTION OF THE LLJ FROM THE ECMWF/NAM...FAVOR THE ARW/NSSL-WRF
CAMP...WITH A COMPLEX OF STORMS WORKING EAST ACROSS THE AREA THROUGH
THE NIGHT...WITH CONVECTIVE COVERAGE AND INTENSITY SLOWLY
DIMINISHING AFTER 6Z.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 400 AM CDT WED MAY 29 2013
CUTOFF UPPER CIRCULATION DEVELOPS AND LINGERS ACROSS THE HIGH
PLAINS AND WESTERN GREAT LAKES INTO THE COMING WEEKEND. AS THE
UPPER LOW TAKES FORM OVER THE NORTHERN PLAINS THROUGH THURSDAY...
A BELT OF FASTER WESTERLY FLOW ASSOCIATED WITH A SHORT WAVE
TROUGH WILL MOVE EAST FROM THE CENTRAL PLAINS TO THE MIDWEST.
CLOUDS WILL REMAIN ABUNDANT OVER THE REGION...AND WILL LIMIT
SIGNIFICANT DESTABILIZATION. HOWEVER...LARGE SCALE ASCENT FROM
THE INCOMING SHORT WAVE AND STEEPENING MID LEVEL LAPSE WILL LIKELY
SUPPORT SOME STRONG TO SEVERE STORMS ACROSS CENTRAL AND SOUTHERN
MINNESOTA THURSDAY AFTERNOON AND THURSDAY NIGHT. THE SURFACE LOW
WILL DEEPEN AND OCCLUDE IN EASTERN NORTH DAKOTA INTO THURSDAY
NIGHT...AND WILL HELP PUSH THE COLD FRONT EAST INTO CENTRAL
MINNESOTA. WE SHOULD SEE HIGH POPS INTO THURSDAY AFTERNOON AS
THIS SYSTEM MOVES THROUGH...AND MAINLY OVER EASTERN AREAS INTO
THURSDAY NIGHT AHEAD OF COLD FRONT. HAIL AND STRONG WINDS WILL BE
THE MAIN THREATS...ALONG WITH HEAVY RAIN. WILL TRAIL POPS OFF TO
THE WEST DURING THE AFTERNOON. THE 00Z ECMWF IS MOST CONSISTENT
WITH DRIVING A DRY SLOT NORTHEAST OVER THE AREA INTO
FRIDAY...LIMITING SIGNIFICANT CONVECTION FURTHER EAST IN THE
REMNANT WARM SECTOR INTO WESTERN WISCONSIN. THIS WILL LIMIT SEVERE
WEATHER DEVELOPMENT ON FRIDAY...WITH THE DAY 3 OUTLOOK MAINLY
SOUTHEAST OF OUR CWA.
SYSTEM SLOW TO MOVE THROUGH THE AREA...WITH COLD AIR CIRCULATING
OVER THE REGION WELL INTO THE WEEKEND. EXPECTING DRIER CONDITIONS
DEVELOPING SATURDAY NIGHT AND LINGERING INTO MONDAY. TEMPERATURES
WILL RANGE SOME 5 TO 10 DEGREES BELOW AVERAGE THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 559 AM CDT WED MAY 29 2013
WARM FRONT ACROSS CENTRAL IOWA THIS MORNING WILL HEAD NORTH TODAY.
DESPITE CONVECTIVE CLOUD DEBRIS COMING OVERHEAD THIS
MORNING...ENOUGH BREAKS HAVE DEVELOPED WEST OF THE RETREATING
STRATUS DECK OVER ERN MN/WRN WI TO GET SOME DENSE FOG GOING ACROSS
MN. GIVEN THE CIRRUS BLOCKING THE SUN...THIS MAY SLOW THE
IMPROVEMENTS SOME NOTED IN THE STC/AXN/RWF TAFS. RAP/NAM
INDICATING POTENTIAL FOR THIS FOG TO LIFT INTO A STRATUS LAYER
THIS MORNING THAT WILL THEN TRACK NORTH WITH THE WARM FRONT...SO
WILL HAVE TO WATCH FOR THAT IN THE MORNING. BEHIND THE WARM
FRONT...MOIST/UNSTABLE AIRMASS WILL BE IN PLACE...THOUGH NAM/RAP
SOUNDINGS SHOW ATMO REMAINING CAPPED UNTIL 20Z...SO HELD OFF ON
ANY TS MENTION UNTIL AFTER THEN. BECAUSE OF THIS CAP...CURRENT
THINKING IS THE HRRR IS TOO AGGRESSIVE WITH TSRA GENERATION
BETWEEN 15Z AND 20Z. FOR THE THUNDER...FOLLOWED THE TREND OF THE
ARW FOR TIMING THUNDER THROUGH. EXPECT STORMS TO INITIATE IN WRN
MN THIS AFTERNOON...AND WORK EAST DURING THE EVENING. OUTSIDE OF
THAT...WILL HAVE TO WATCH A COUPLE OF POTENTIAL SHOWER AREAS THIS
MORNING. FIRST IS THUNDERSTORMS CURRENTLY WEST OF SIOUX FALLS.
MOST GUIDANCE HAS KEPT THIS AREA WEST OF TERMINALS...BUT THEY
COULD WORK INTO THE AXN AREA LATER THIS MORNING...SO HAVE A VCSH
MENTION THERE. OTHER AREA OF SHOWERS FOR THIS MORNING IS JUST
GETTING GOING EAST OF OMAHA...AND WILL TRACK NORTHEAST TOWARD
EAU...WHERE A VCSH WAS MENTIONED AROUND 18Z.
KMSP...AFTER VALLEY FOG AND BR BURNS OFF THIS MORNING...WILL HAVE
TO SEE IF SOME SUB 017 STRATUS WORKS UP WITH THE WARM FRONT.
MODERATE CONFIDENCE AT BEST ON THIS HAPPENING...BUT WITH LAMP
GUIDANCE SHOWING MVFR CIGS THROUGH 18Z...DECIDED TO KEEP IT. LOTS
OF UNCERTAINTY WITH THUNDER POTENTIAL TODAY. HRRR RUNS CONTINUE TO
BE AGGRESSIVE WITH TSRA MOVING INTO THE FIELD AS EARLY AS 19Z...BUT
RAP SOUNDINGS CONTINUE TO BE CAPPED THROUGH ABOUT 21Z...SO WILL
CONTINUE TO PLAY UP THE IDEA THAT STORMS INITIATE AROUND 20Z OVER
WRN MN...AND PUSH INTO THE TWIN CITIES AREA AFTER 00Z. THOUGH
GIVEN DEGREE OF INSTABILITY...IF SOMETHING WERE TO BREAK THROUGH
THE CAP...THINGS WOULD GO QUICKLY.
/OUTLOOK FOR KMSP/
THU...MVFR OR LOWER CIGS LIKELY. SHRA/TSRA LIKELY. WINDS S 15-20
KTS.
FRI...MVFR OR LOWER CIGS LIKELY. CHANCE SHRA/TSRA. WINDS SW 10-15
KTS.
SAT...MVFR CIGS POSSIBLE. CHANCE SHRA/TSRA. WINDS WNW 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...DWE
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS HASTINGS NE
808 AM CDT WED MAY 29 2013
.UPDATE...
ISSUED AT 808 AM CDT WED MAY 29 2013
GIVEN INCREASE IN SHOWERS/FAIRLY WEAK THUNDERSTORMS ACROSS MUCH OF
THE SOUTHEAST 1/4 OF THE CWA ALREADY THIS MORNING...HAVE UPPED
POPS TO 50 PERCENT THIS MORNING ACROSS MUCH OF THE EASTERN 1/2 OF
THE CWA...WHILE KEEPING LOWER POPS IN THE WEST. AM NOT
ANTICIPATING SEVERE STORMS THIS MORNING...BUT SOME SMALL HAIL IS
NOT OUT OF THE QUESTION. ITS A COMPLEX CONVECTIVE SCENARIO
TODAY..WITH THE PRESENCE OF SEVERAL SUBTLE DISTURBANCES IN THE MID
LEVEL FLOW OUT AHEAD OF THE PRIMARY SHORTWAVE TROUGH APPROACHING
FROM THE ROCKIES...VERY POSSIBLY ENSURING THAT AT LEAST SOME
PORTION OF THE CWA WILL SEE RAIN AT ANY GIVEN TIME TODAY.
ON ANOTHER NOTE...REGARDING THE THURSDAY/FRIDAY FIRE WEATHER
CONCERNS FOR OUR WESTERN CWA OUTLINED IN THE PREVIOUS
DISCUSSION...UPON FURTHER INSPECTION THE OFFICIAL FIRE WEATHER
FUEL STATUS FOR ALL NEBRASKA ZONES WAS SET TO UNFAVORABLE FOR
LARGE FIRE GROWTH AS OF YESTERDAY. THIS BASICALLY MEANS THAT
VEGETATION IS GREEN ENOUGH/WET ENOUGH TO PRECLUDE MAJOR FIRE
WEATHER PROBLEMS...ALTHOUGH OF COURSE CAUTION SHOULD STILL BE
USED WHEN BURNING. AS A RESULT OF THIS UNFAVORABLE FUEL
STATUS...WILL BE REMOVING ELEVATED FIRE DANGER MENTION FROM THE
HAZARDOUS WEATHER OUTLOOK.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 406 AM CDT WED MAY 29 2013
MAIN FORECAST CONCERN WILL BE
CHANCES FOR THUNDERSTORMS.
RADAR FROM KLNX SHOWS THAT MANY OF THE THUNDERSTORMS TO THE WEST
HAVE DIMINISHED BUT A RAIN SHIELD REMAINS. THERE ARE A COUPLE OF
BOUNDARIES THAT ARE SHOWING UP ON KUEX RADAR...ONE FROM THE
CONVECTION TO THE WEST AND ANOTHER FROM CONVECTION TO THE SOUTH.
WHEN THESE COLLIDE APPEARS TO BE THE BEST CHANCE FOR SOME SHOWERS
AND THUNDERSTORMS EARLY THIS MORNING. THERE HAVE BEEN A FEW THAT
GOT STARTED BUT SOON WANED.
MODELS ARE SIMILAR WITH THE UPPER LEVEL LOW THAT MOVES FROM THE
NORTHERN ROCKIES INTO THE NORTHERN HIGH PLAINS TODAY AND TONIGHT.
THERE IS A SURFACE LOW ON THE HIGH PLAINS THAT TRIES TO MOVE
EAST...BUT DOES NOT MAKE IT THROUGH THE AREA. THE SURFACE PRESSURE
GRADIENT TIGHTENS THIS MORNING AHEAD OF THE SURFACE LOW. WINDS
WILL START TO INCREASE. THE STRONGEST WINDS WILL BE IN THE
SOUTHERN PART OF THE FORECAST AREA...BUT BREEZY CONDITIONS ARE
EXPECTED ACROSS THE AREA TODAY. WILL KEEP THE WIND ADVISORY AS IS
FOR NOW.
THE NEXT CONCERN WILL BE WHEN THUNDERSTORMS WILL DEVELOP. THE
UPPER LEVEL WAVE WILL START TO AFFECT THE AREA THIS MORNING AND
SOME THUNDERSTORM DEVELOPMENT IS NOT OUT OF THE QUESTION. THE NAM
AND THE GFS SHOW A DEFINITIVE INCREASE IN QPF DURING THE MORNING
BUT THE RAP AND 4KM WRF BOTH HOLD OFF UNTIL LATER. WILL KEEP SOME
LOW POPS IN FOR THE MORNING...BUT RAMP IT UP LATER THIS MORNING
AND EARLY THIS AFTERNOON WHEN THE UPPER WAVE IS MOVING INTO THE
AREA. SEVERE WEATHER IS EXPECTED DURING THE AFTERNOON AND EVENING
WHEN MUCAPES ARE EXPECTED TO BE OVER 3500 J/KG. THE SEVERE WEATHER
WILL LIKELY CONTINUE INTO THE EVENING BUT THE SEVERE THREAT WILL
DIMINISH LATER TONIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 406 AM CDT WED MAY 29 2013
MAIN STORY: A REPRIEVE FROM THE THREAT OF TSTMS WILL OCCUR AS
TEMPS TUMBLE TO BELOW NORMAL THIS WEEKEND...THEN THE THREAT
RETURNS EARLY NEXT WEEK AS SUMMER WARMTH RETURNS.
ALOFT: THE TROF CURRENTLY MOVING THRU THE W WILL CLOSE OFF OVER
THE NRN PLAINS THU NGT-FRI BEFORE OPENING UP AND SLOWLY MIGRATING
INTO THE GREAT LAKES AND MIDWEST THIS WEEKEND. A MODEST SHRTWV
RIDGE WILL ADVANCE INTO THE PLAINS SUN-MON...AS THE NEXT TROF
MOVES INTO THE PAC NW. ALL THE WHILE THE WESTERLIES WILL GRADUALLY
LIFT BACK INTO THE NRN USA.
SFC: A COOL FRONT WILL MOVE THRU LATE THU AFTN/EVE. HOWEVER...THE
TAIL END OF THE FRONT MAY NOT ENTIRELY CLEAR THE SE FRINGE OF OUR
FCST AREA UNTIL FRI EVNG. THIS FRONT WILL BE FOLLOWED BY A SECONDARY
STRONGER COLD FRONT FRI EVNG. HIGH PRES DRIFTS THRU SUN WITH RETURN
FLOW INTENSIFYING WITH ITS DEPARTURE TO THE E AND REDEVELOPMENT OF
THE LEE TROF...AS LOW PRES HEADS E ALONG THE USA-CAN BORDER. HEAT
BUILDS OVER THE REGION MON-TUE UNTIL THE NEXT COOL FRONT MOVES THRU
TUE NGT OR WED. COOL HIGH PRES THEN BUILDS IN THU.
HAZARDS: FIRE WX MAY BECOME A CONCERN THU/FRI BETWEEN 2PM-8PM.
ATTM DO NOT ENVISION A RFW BUT FIRE DANGER COULD BE ELEVATED.
THERE ARE MULTIPLE CHANCES FOR TSTMS THU-FRI BUT COVERAGE AND
INTENSITY WILL BE LOW DUE TO DIMINISHING MSTR/INSTABILITY. SOME
SVR TSTMS WILL BE POSSIBLE EARLY NEXT WEEK AS INSTABILITY
INCREASES.
THE DAILY DETAILS...
THU: THE BACKSIDE OF AN MCS MAY STILL LINGER SE OF THE TRI-CITIES
IN THE MRNG. OTHERWISE DECREASING CLOUDS.
THE DRYLINE WILL PRESS INTO THE FCST AREA IN THE WARM SECTOR OF A
992 MB SFC LOW OVER THE DAKOTAS...WITH ITS ASSOCIATED COOL FRONT
DROPPING INTO THE NW FRINGE LATE. THE LFQ OF THE 80 KT ULJ WILL BE
OVER THE CNTRL PLAINS...BUT HIGH QUALITY MSTR WILL BE RAPIDLY ON THE
DECREASE. AN ISOLATED SHWR/TSTM IS POSSIBLE...MAINLY E OF HWY 281.
FIRE DANGER: WE NEED TO WATCH ALONG AND W OF HWY 183. USED LOWER
NAM 2M DWPTS WHICH DROPS INTO THE UPR 30S. WINDS LOOK MARGINAL.
FRI: WEAK HIGH PRES BUILDS IN BEFORE SECONDARY COLD FRONTAL
PASSAGE. A BREEZY DAY W OF HWY 281. THERE IS A VERY LOW
PROBABILITY FOR AN ISOLATED SHWR/TSTM IN VICINITY OF THE
APPROACHING FRONT AND THE STALLED FRONT OVER THE SE. FIRE DANGER
COULD BE ELEVATED AGAIN W OF HWY 183.
SAT: BREEZY AND COOL WITH HIGH TEMPS ABOUT 10F COOLER THAN
NORMAL. COULD SEE A FEW SPRINKLES N OF I-80 IN THE AFTN.
SUN: NICE AND COMFORTABLE. A GOOD DAY TO OPEN UP THE HOUSE.
SUN NGT: A STRONG PULSE OF WAA/MSTR TRANSPORT AS 40 KT LLJ
DEVELOPS. MSTR WILL INITIALLY BE LACKING SO IT APPEARS THIS
PROCESS WILL NOT DESTABILIZE THE ATMS. JUST TOO SOON SO THE FCST
IS DRY.
MON-TUE: RISK OF TSTMS INCREASES AND PROBABLY PEAKS TUE. WE ARE
PROBABLY TOO LOW ON OUR TEMPS BY 3-5F. WOULD NOT BE SURPRISED TO SEE
MID 90S SW OF THE TRI-CITIES.
&&
.AVIATION...(FOR THE 12Z KGRI TAF THROUGH 12Z THURSDAY MORNING)
ISSUED AT 555 AM CDT WED MAY 29 2013
LOWER CLOUDS ARE MOVING INTO THE KGRI TERMINAL AREA THIS MORNING.
THEY SHOULD BE MAINLY MVFR THROUGH MUCH OF THE DAY. WINDS WILL
INCREASE DURING THE MORNING AND BE BREEZY DURING THE AFTERNOON AND
INTO THE EVENING. THERE ARE CHANCES FOR SOME THUNDER MUCH OF THE
DAY BUT TRIED TO DEFINE THE MOST LIKELY TIMES. THE FIRST ROUND
SHOULD BE DURING THE AFTERNOON INTO THE EVENING WITH A BETTER
CHANCE LATER TONIGHT.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR KSZ006-007-017>019.
&&
$$
UPDATE...PFANNKUCH
SHORT TERM...JCB
LONG TERM...HALBLAUB
AVIATION...JCB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
556 AM CDT WED MAY 29 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 406 AM CDT WED MAY 29 2013
MAIN FORECAST CONCERN WILL BE
CHANCES FOR THUNDERSTORMS.
RADAR FROM KLNX SHOWS THAT MANY OF THE THUNDERSTORMS TO THE WEST
HAVE DIMINISHED BUT A RAIN SHIELD REMAINS. THERE ARE A COUPLE OF
BOUNDARIES THAT ARE SHOWING UP ON KUEX RADAR...ONE FROM THE
CONVECTION TO THE WEST AND ANOTHER FROM CONVECTION TO THE SOUTH.
WHEN THESE COLLIDE APPEARS TO BE THE BEST CHANCE FOR SOME SHOWERS
AND THUNDERSTORMS EARLY THIS MORNING. THERE HAVE BEEN A FEW THAT
GOT STARTED BUT SOON WANED.
MODELS ARE SIMILAR WITH THE UPPER LEVEL LOW THAT MOVES FROM THE
NORTHERN ROCKIES INTO THE NORTHERN HIGH PLAINS TODAY AND TONIGHT.
THERE IS A SURFACE LOW ON THE HIGH PLAINS THAT TRIES TO MOVE
EAST...BUT DOES NOT MAKE IT THROUGH THE AREA. THE SURFACE PRESSURE
GRADIENT TIGHTENS THIS MORNING AHEAD OF THE SURFACE LOW. WINDS
WILL START TO INCREASE. THE STRONGEST WINDS WILL BE IN THE
SOUTHERN PART OF THE FORECAST AREA...BUT BREEZY CONDITIONS ARE
EXPECTED ACROSS THE AREA TODAY. WILL KEEP THE WIND ADVISORY AS IS
FOR NOW.
THE NEXT CONCERN WILL BE WHEN THUNDERSTORMS WILL DEVELOP. THE
UPPER LEVEL WAVE WILL START TO AFFECT THE AREA THIS MORNING AND
SOME THUNDERSTORM DEVELOPMENT IS NOT OUT OF THE QUESTION. THE NAM
AND THE GFS SHOW A DEFINITIVE INCREASE IN QPF DURING THE MORNING
BUT THE RAP AND 4KM WRF BOTH HOLD OFF UNTIL LATER. WILL KEEP SOME
LOW POPS IN FOR THE MORNING...BUT RAMP IT UP LATER THIS MORNING
AND EARLY THIS AFTERNOON WHEN THE UPPER WAVE IS MOVING INTO THE
AREA. SEVERE WEATHER IS EXPECTED DURING THE AFTERNOON AND EVENING
WHEN MUCAPES ARE EXPECTED TO BE OVER 3500 J/KG. THE SEVERE WEATHER
WILL LIKELY CONTINUE INTO THE EVENING BUT THE SEVERE THREAT WILL
DIMINISH LATER TONIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 406 AM CDT WED MAY 29 2013
MAIN STORY: A REPRIEVE FROM THE THREAT OF TSTMS WILL OCCUR AS
TEMPS TUMBLE TO BELOW NORMAL THIS WEEKEND...THEN THE THREAT
RETURNS EARLY NEXT WEEK AS SUMMER WARMTH RETURNS.
ALOFT: THE TROF CURRENTLY MOVING THRU THE W WILL CLOSE OFF OVER
THE NRN PLAINS THU NGT-FRI BEFORE OPENING UP AND SLOWLY MIGRATING
INTO THE GREAT LAKES AND MIDWEST THIS WEEKEND. A MODEST SHRTWV
RIDGE WILL ADVANCE INTO THE PLAINS SUN-MON...AS THE NEXT TROF
MOVES INTO THE PAC NW. ALL THE WHILE THE WESTERLIES WILL GRADUALLY
LIFT BACK INTO THE NRN USA.
SFC: A COOL FRONT WILL MOVE THRU LATE THU AFTN/EVE. HOWEVER...THE
TAIL END OF THE FRONT MAY NOT ENTIRELY CLEAR THE SE FRINGE OF OUR
FCST AREA UNTIL FRI EVNG. THIS FRONT WILL BE FOLLOWED BY A SECONDARY
STRONGER COLD FRONT FRI EVNG. HIGH PRES DRIFTS THRU SUN WITH RETURN
FLOW INTENSIFYING WITH ITS DEPARTURE TO THE E AND REDEVELOPMENT OF
THE LEE TROF...AS LOW PRES HEADS E ALONG THE USA-CAN BORDER. HEAT
BUILDS OVER THE REGION MON-TUE UNTIL THE NEXT COOL FRONT MOVES THRU
TUE NGT OR WED. COOL HIGH PRES THEN BUILDS IN THU.
HAZARDS: FIRE WX MAY BECOME A CONCERN THU/FRI BETWEEN 2PM-8PM.
ATTM DO NOT ENVISION A RFW BUT FIRE DANGER COULD BE ELEVATED.
THERE ARE MULTIPLE CHANCES FOR TSTMS THU-FRI BUT COVERAGE AND
INTENSITY WILL BE LOW DUE TO DIMINISHING MSTR/INSTABILITY. SOME
SVR TSTMS WILL BE POSSIBLE EARLY NEXT WEEK AS INSTABILITY
INCREASES.
THE DAILY DETAILS...
THU: THE BACKSIDE OF AN MCS MAY STILL LINGER SE OF THE TRI-CITIES
IN THE MRNG. OTHERWISE DECREASING CLOUDS.
THE DRYLINE WILL PRESS INTO THE FCST AREA IN THE WARM SECTOR OF A
992 MB SFC LOW OVER THE DAKOTAS...WITH ITS ASSOCIATED COOL FRONT
DROPPING INTO THE NW FRINGE LATE. THE LFQ OF THE 80 KT ULJ WILL BE
OVER THE CNTRL PLAINS...BUT HIGH QUALITY MSTR WILL BE RAPIDLY ON THE
DECREASE. AN ISOLATED SHWR/TSTM IS POSSIBLE...MAINLY E OF HWY 281.
FIRE DANGER: WE NEED TO WATCH ALONG AND W OF HWY 183. USED LOWER
NAM 2M DWPTS WHICH DROPS INTO THE UPR 30S. WINDS LOOK MARGINAL.
FRI: WEAK HIGH PRES BUILDS IN BEFORE SECONDARY COLD FRONTAL
PASSAGE. A BREEZY DAY W OF HWY 281. THERE IS A VERY LOW
PROBABILITY FOR AN ISOLATED SHWR/TSTM IN VICINITY OF THE
APPROACHING FRONT AND THE STALLED FRONT OVER THE SE. FIRE DANGER
COULD BE ELEVATED AGAIN W OF HWY 183.
SAT: BREEZY AND COOL WITH HIGH TEMPS ABOUT 10F COOLER THAN
NORMAL. COULD SEE A FEW SPRINKLES N OF I-80 IN THE AFTN.
SUN: NICE AND COMFORTABLE. A GOOD DAY TO OPEN UP THE HOUSE.
SUN NGT: A STRONG PULSE OF WAA/MSTR TRANSPORT AS 40 KT LLJ
DEVELOPS. MSTR WILL INITIALLY BE LACKING SO IT APPEARS THIS
PROCESS WILL NOT DESTABILIZE THE ATMS. JUST TOO SOON SO THE FCST
IS DRY.
MON-TUE: RISK OF TSTMS INCREASES AND PROBABLY PEAKS TUE. WE ARE
PROBABLY TOO LOW ON OUR TEMPS BY 3-5F. WOULD NOT BE SURPRISED TO SEE
MID 90S SW OF THE TRI-CITIES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 555 AM CDT WED MAY 29 2013
LOWER CLOUDS ARE MOVING INTO THE KGRI TERMINAL AREA THIS MORNING.
THEY SHOULD BE MAINLY MVFR THROUGH MUCH OF THE DAY. WINDS WILL
INCREASE DURING THE MORNING AND BE BREEZY DURING THE AFTERNOON AND
INTO THE EVENING. THERE ARE CHANCES FOR SOME THUNDER MUCH OF THE
DAY BUT TRIED TO DEFINE THE MOST LIKELY TIMES. THE FIRST ROUND
SHOULD BE DURING THE AFTERNOON INTO THE EVENING WITH A BETTER
CHANCE LATER TONIGHT.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...WIND ADVISORY FROM 10 AM THIS MORNING TO 9 PM CDT THIS EVENING
FOR KSZ006-007-017>019.
&&
$$
SHORT TERM...JCB
LONG TERM...HALBLAUB
AVIATION...JCB
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
732 AM EDT WED MAY 29 2013
.SYNOPSIS...
DRY ATLANTIC HIGH PRESSURE WILL DOMINATE OUR WEATHER THROUGH THE
WORK WEEK. THE HIGH WILL MOVE OFF THE EAST COAST OVER THE
WEEKEND...AS A WEAK COLD FRONT PUSHES INTO THE AREA EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 615 AM EDT WEDNESDAY...STRATUS HAS STARTED TO DEVELOP OVER NRN
GA AND THE SC MIDLANDS. BASED ON THE ORIENTATION OF THE LLVL
FLOW...I THINK THAT THE UPPER SAVANNAH RIVER VALLEY MAY SEE SOME
STRATUS IN AN HOUR OR TWO AND I/VE UPPED CLOUD COVER THERE.
HOWEVER...THE LLVL FLOW IS QUITE WEAK AND I DON/T EXPECT THE LOW
CLOUDS TO EXPAND EAST OF ANDERSON OR AS FAR NORTH AS CHARLOTTE. AT
LEAST NOT UNTIL WE START TO MIX AND THEN CLOUDS WILL DEVELOP AS A
HIGHER CELLULAR CU DECK.
AS OF 245 AM EDT WEDNESDAY...STRATO-CU CONTINUES TO DEVELOP IN THE
SLY UPSLOPE FLOW ACROSS THE MTNS OF THE WRN CAROLINAS AND NE GA. AT
LEAST THAT/S WHERE THE CLOUDS ARE THE THICKEST AT THIS TIME.
ELSEWHERE IT/S MAINLY CLEAR. THIS GENERAL SKY TREND SHOULD CONTINUE
THROUGH ABOUT MID-MORNING. THERE STILL MIGHT BE A BRIEF PERIOD OF
LOW STRATUS AROUND SUNRISE...BUT A POCKET OF DRIER AIR WORKING INTO
THE FA FROM THE SOUTH AND CONTINUED LIGHT MIXING MORE THAN LIKELY
WILL KEEP THIS FROM HAPPENING. FOR THIS AFTERNOON A DEEP LAYER RIDGE
WILL CONTINUE TO BUILD ACROSS THE REGION AND LITTLE IF ANY
CONVECTION IS ANTICIPATED. THE ONE AREA THAT COULD SEE SOME ISOLATED
SHRA/TSTM ACTIVITY IS RIGHT ALONG THE TN LINE. AND ANYTHING THAT
DEVELOPS IN THIS AREA SHOULD SUBSEQUENTLY DRIFT INTO ERN TN. WE
ALREADY HAD A SMALL AREA OF SLIGHT CHANCE POPS IN THIS AREA AND I
ONLY MADE SOME MINOR TWEAKS.
THE ONE FORECAST ELEMENT OF NOTE TONIGHT IS THAT MORE OF THE MODEL
GUIDANCE WANTS TO DEVELOP STRATUS AFTER MIDNIGHT. THE NAM BUFKIT
SOUNDINGS STRONGLY IMPLY THIS WILL HAPPEN AND IT/S OFTEN RIGHT. WE
ONLY HAVE A MODEST INCREASE IN SKY COVER OVERNIGHT TO ACCOUNT FOR
THIS AS I/M STILL A LITTLE SKEPTICAL CONSIDERING THE STRENGTH OF THE
RIDGE.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 145 AM WEDNESDAY...QUIET WEATHER WILL CONTINUE IN THE SHORT
TERM...AS THE 500 MB HIGH WILL BE AT MAX STRENGTH AROUND 00Z FRI AT
590 DAM INVOF THE VA CAPES. FROM THERE THE HIGH WILL BEGIN A SLOW
WEAKENING TREND AND A SHIFT TO THE EAST. MODELS ARE GENERALLY
LACKING IN QPF RESPONSE BOTH THU AND FRI. AND LOOKING AT THE FCST
SNDGS...THE SUBSIDENCE INVERSION SHUD PRECLUDE ANY DEEP CONVECTION.
(ALTHO A FEW ISOLD CELLS CANNOT BE RULED OUT IN THE MTNS THIS TIME
OF YEAR). HIGHS WILL BE A CATEORY OR TWO ABOVE NORMAL BOTH DAYS.
OVERNIGHT LOWS WILL BE A LITTLE TRICKIER...AS A PERSISTENT SELY FLOW
OFF THE ATLANTIC MAY PRODUCE SOME MORNING STRATUS BOTH THURSDAY AND
FRIDAY MORNINGS. THIS IS MOST LIKELY TO OCCUR IN THE WESTERN HALF OF
THE CWFA. ANY LOW CLOUDS SHUD QUICKLY SCATTER OUT BY MIDDAY BOTH
DAYS.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 200 AM WEDNESDAY...AN UPPER RIDGE THAT HAS DOMINATED THE EAST
COAST WILL BREAK DOWN THIS WEEKEND...AND BE REPLACED BY A POSITIVELY
TILTED UPPER TROF FOR SUNDAY THRU TUESDAY. THE TROF WILL BRING
PLENTY OF MOISTURE WITH A WEAKLY FORCED COLD FRONT. SATURDAY LOOKS
LIKE THE LAST DRY DAY BEFORE UNSETTLED WEATHER RETURNS TO THE CWFA.
THERE MAY BE SOME MODEST INCREASE IN MOISTURE SATURDAY AHEAD OF THE
TROF. AND WITH SUBSIDENCE INVERSION WEAKENING...COULD SEE A FEW
SHWRS AND TSTMS DEVELOPING THE NC MTNS. WILL GO WITH SLGT CHC FOR
SAT AFTN. AS THE FRONT APPROACHES ON SUNDAY...CHC POPS RETURN TO THE
AREA. THE FRONT WILL SLOWLY CROSS THE CWFA MONDAY AND
TUESDAY...KEEPING A SOLID CHC ON MONDAY...SHIFTING TO EASTERN HALF
OF THE AREA ON TUESDAY. DECENT AMOUNT OF CAPE IN THE GFS AND
ECWMF...BUT SHEAR LOOKS FAIRLY WEAK IN THIS UPCOMING PATTERN. SO NOT
SURE HOW MUCH CONVECTION WILL BE ABLE TO ORGANIZE ALONG/INVOF THE
FRONTAL BNDRY. TEMPS WILL TO BE SLIGHTLY ABOVE NORMAL SATURDAY AND
SUNDAY...THEN NEAR NORMAL MONDAY AND TUESDAY.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT AND ELSEWHERE...STRATUS HAS STARTED TO DEVELOP IN TWO
LOCATIONS ACROSS THE REGION. THE LARGER AREA HAS DEVELOPED OVER
NORTH CENTRAL GA...BETWEEN MACON...ATLANTA AND ATHENS. THESE CLOUDS
WERE MAINLY MOVING OFF TO THE NORTH. THE RUC 925 MB WINDS REMAIN OUT
OF THE SOUTH ACROSS THIS AREA THE NEXT CPL HOURS AND THESE CLOUDS
SHOULD MISS ALL THE TAF SITES TO THE WEST...THOUGH IT WILL BE CLOSE
AT KAND AND I/VE ADDED FEW010. ANOTHER AREA WAS DEVELOPING NORTH OF
AIKEN OVER THE MIDLANDS. THIS AREA HAS NOT BEEN EXPANDING AND IS
SITUATED IN AN AREA OF FAIRLY LOW DEWPOINTS. EVEN THOUGH THE LLVL
FLOW WOULD TAKE THESE CLOUDS TOWARD KCLT...THEY WOULDN/T ARRIVE
UNTIL 13 UTC AND BY THEN THEY SHOULD HAVE MIXED OUT OR AT LEAST
LIFTED INTO A SCT CU DECK. OTHERWISE IT WILL BE A DRY DAY ACROSS THE
REGION. WINDS WILL BE A LITTLE LIGHTER THAN YDAY...AVERAGING 5 TO 8
KTS FROM THE SOUTH. CHANCES FOR MORE WIDESPREAD STRATUS ARE LOOKING
BETTER TONIGHT. FOR NOW I/VE JUST ADDED FEW010 TO THE I-85 CORRIDOR
TAF SITES. THERE COULD BE MORE FOG AROUND TONIGHT AS THE LOW WILL BE
LIGHT. I/D CERTAINLY EXPECT QUITE A BIT JUST TO OUR EAST AT THE VERY
LEAST WHERE THE CONDENSATION PRESSURE DEFICITS FALL TO ZERO.
OUTLOOK...GENERALLY FAIR CONDITIONS ARE EXPECTED THROUGH SATURDAY.
BRIEF MORNING RESTRICTIONS IN FOG OR HAZE WILL BE POSSIBLE...MAINLY
IN THE MTN VALLEYS. CHANCES FOR MAINLY AFTERNOON/EVENING SHOWERS AND
THUNDERSTORMS WILL INCREASE SIGNIFICANTLY BY SUNDAY AFTERNOON...AS A
COLD FRONT APPROACHES FROM THE TENN VALLEY.
CONFIDENCE TABLE...
11-17Z 17-23Z 23-05Z 05-11Z
KCLT HIGH 98% HIGH 100% HIGH 100% HIGH 90%
KGSP HIGH 100% HIGH 100% HIGH 93% MED 68%
KAVL HIGH 98% HIGH 100% HIGH 93% MED 71%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 90%
KGMU HIGH 100% HIGH 100% HIGH 93% MED 68%
KAND MED 73% HIGH 100% HIGH 93% MED 66%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...ARK
NEAR TERM...MCAVOY
SHORT TERM...ARK
LONG TERM...ARK
AVIATION...MCAVOY
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
906 AM CDT WED MAY 29 2013
.UPDATE...
TEMPERATURES ARE WARMING QUICKLY THIS MORNING WITH MOST SURFACE
OBS ALREADY WELL INTO THE 70S TO NEAR 80. FORECAST HIGHS TEMPS IN
THE LOW 80S ON THE PLATEAU AND UPPER 80S ELSEWHERE STILL LOOK ON
TRACK...AND A FEW LOCATIONS COULD TOUCH THE 90 DEGREE MARK THIS
AFTERNOON. SATELLITE IMAGERY AND REGIONAL SURFACE OBS SHOW AN
AREA OF DEEPER MOISTURE SPREADING NORTHWESTWARD ACROSS
MISSISSIPPI/ALABAMA WITH PWATS UP TO 1.50 INCHES PER 12Z LIX
SOUNDING. THIS MOISTURE WILL ENTER WESTERN TENNESSEE LATER
TODAY...AND A COUPLE OF MODELS LIKE THE HRRR AND 4.0 KM WRF
INDICATE AN ISOLATED SHOWER IS NOT OUT OF THE QUESTION ALONG OUR
WESTERN AND SOUTHWESTERN CWA BORDERS. HOWEVER...RISING HEIGHTS
ALOFT ACROSS THE MID STATE DUE TO THE LARGE TROUGH EJECTING OUT
INTO THE PLAINS COMBINED WITH SUBSTANTIAL DRY AIR THROUGHOUT THE
COLUMN IS EXPECTED TO SUPPRESS CONVECTIVE DEVELOPMENT AND WILL
LEAVE INHERITED DRY FORECAST AS IS. REST OF FORECAST ALSO REMAINS
ON TRACK AND NO CHANGES WERE MADE.
SHAMBURGER
&&
.PREV DISCUSSION... /ISSUED 330 AM CDT WED MAY 29 2013/
DISCUSSION...
UPPER RIDGING EXTENDS FROM JUST SOUTH OF BERMUDA IN THE ATLANTIC NW
THROUGH GA AND TN. UPPER TROUGH MOVING EAST ACROSS THE NORTHERN
ROCKIES WITH A GENERAL SW FLOW ALOFT FROM TX NE TO THE GREAT LAKES.
THE AFOREMENTIONED UPPER TROUGH WILL CONTINUE TO MOVE EAST AND WE
WILL SEE THE RIDGE AXIS SHIFT EAST AS WELL. THOUGH 18Z CAP EROSION
IS PRONOUNCED TODAY...MRH LEVELS ARE RATHER LOW AND CAPES AS WELL.
NOT SEEING MUCH IN THE WAY OF CONVECTIVE DEVELOPMENT ACROSS THE MID
STATE. HOWEVER...AS WE BEGIN TO GET MORE AND MORE INTO THE SW FLOW
ALOFT IN THE DAYS TO COME...CAPES AND MOISTURE WILL BE ON THE
INCREASE. LOW POPS WILL BE NEEDED ON THURSDAY AND WILL SLOWLY
INCREASE INTO THE WEEKEND. TEMPERATURES WILL CONTINUE TO RUN A
LITTLE ABOVE NORMAL...BUT ANY ENHANCED THERMAL RIDGING SHOULD REMAIN
CONFINED TO OLD MEXICO.
VERSUS THE NEAR TERM GUIDANCE...WILL ELECT TO DIFFER LITTLE IF ANY
FROM THE MAV. MET DATA LOOKING A LITTLE TOO LOW WITH DAY TIME
HIGHS.
IN THE EXT FCST...STILL EXPECTING THE COLD FRONT TO APPROACH THIS
WEEKEND WITH THE FROPA OCCURRING SUNDAY NIGHT. THUS...POPS WILL BE
HIGHEST SAT NT AND SUNDAY. STILL LOOKING AT THE POSSIBILITY OF A FEW
STRONG STORMS FOR SAT AND SUN DURING THE AFT/EVE HOURS. SLIGHTLY
COOLER AND DRIER AIR IS EXPECTED BY TUESDAY BEHIND THE FRONT. WILL
LEAN TOWARD THE SLIGHTLY COOLER EURO MOS THROUGH MUCH OF THE
EXTENDED.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
600 AM CDT WED MAY 29 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 356 AM CDT WED MAY 29 2013
LATEST WATER VAPOR IMAGERY CONTINUED TO SHOW A MESSY PATTERN ACROSS
THE CONUS. A LEADING SHORTWAVE...RESPONSIBLE FOR BRINGING SOME
SCATTERED RAIN SHOWERS TO THE AREA YESTERDAY...WAS MOVING ACROSS
NORTHERN LOWER MICHIGAN/EASTERN UPPER MICHIGAN. TWO MAIN SHORTWAVES
NOTED...ONE MOVING THROUGH WESTERN NEBRASKA AND ANOTHER MOVING
ACROSS NORTHERN TEXAS/WESTERN OKLAHOMA. A TROUGH WAS DIGGING INTO
THE CENTRAL ROCKIES/FOUR CORNERS REGION...ATTEMPTING TO EDGE EAST
INTO THE HIGH PLAINS. SURFACE OBSERVATIONS INDICATED A WARM FRONT
EXTENDING FROM SOUTHERN NEBRASKA NORTHEAST THROUGH SOUTHERN IOWA
INTO NORTHERN ILLINOIS.
THE WARM FRONT IS EXPECTED TO LIFT NORTH TODAY AS THE TROUGH EJECTS
NORTHEAST ACROSS THE CENTRAL PLAINS. SHOWERS AND THUNDERSTORMS ARE
EXPECTED TO DEVELOP ALONG THE FRONT AS IT PUSHES NORTHWARD AND A
SHORTWAVE LIFTS NORTH ACROSS THE UPPER MISSISSIPPI RIVER VALLEY.
THERE IS SOME UNCERTAINTY REGARDING HOW MUCH INSTABILITY BUILDS
ALONG THE FRONT. THE NAM SUGGESTS 0-3 KM MUCAPE VALUES CLIMB INTO
THE 1500 TO 2000 J/KG RANGE THIS AFTERNOON AS WARM...MOIST AIR
SURGES NORTHWARD. THIS SEEMS A BIT AGGRESSIVE GIVEN THE ABUNDANT
CLOUD COVER IN PLACE. ALSO...THE NAM SURFACE DEWPOINTS CLIMB TO
AROUND 70. THE RUC SURFACE DEWPOINTS ARE ALSO WAY TOO HIGH
TODAY...WITH DEWPOINTS CLIMBING INTO THE MID 70S. LOWER TO MID 60S
DEW POINTS ARE MUCH MORE REALISTIC...SO THINKING SURFACE BASED
CAPE VALUES OF AROUND 1000 J/KG IS NOT OUT OF THE QUESTION...BUT
WITH ONLY WEAK 0-6 KM SHEAR. CANNOT RULE OUT AN ISOLATED SEVERE
STORM BUT OVERALL PROBABILITIES APPEAR LOW AT LEAST THROUGH MID
AFTERNOON. WILL HAVE TO KEEP A VERY CLOSE WATCH ON AREAS WEST OF
THE MISSISSIPPI RIVER WHEN THE LOW LEVEL JET INTENSIFIES THIS
EVENING AND 0-1KM SHEAR RAMPS UP. IF STORMS ARE SURFACE BASED OVER
THESE AREAS EARLY THIS EVENING...CANNOT RULE OUT AN ISOLATED
TORNADO MAINLY WEST OF A LAKE CITY...TO HARMONY TO OELWEIN LINE.
WARMER AIR ALOFT MOVES IN...CENTERED AROUND 850 MB...AND SHOULD
EFFECTIVELY CAP THE ATMOSPHERE FOR FURTHER CONVECTIVE DEVELOPMENT
AT LEAST UNTIL 850 MB MOISTURE TRANSPORT KICKS IN LATE THIS
EVENING. SHEAR IS RATHER WEAK...UNTIL THE LOW LEVEL JET GETS GOING
THIS EVENING AND FOCUSES INTO EASTERN SOUTH DAKOTA/SOUTHWEST
MINNESOTA. PLAN ON TEMPERATURES GRADUALLY WARMING THROUGH THE DAY
AS THE FRONT MOVES THROUGH WITH HIGHS TOPPING OUT IN THE UPPER
70S. A FEW LOWER TO MID 80S ARE POSSIBLE OVER PORTIONS OF
NORTHEAST IOWA AND FAR SOUTHWEST WISCONSIN. THE WARM FRONT IS
EXPECTED TO PUSH INTO FAR NORTHERN WISCONSIN THIS EVENING. 850 MB
MOISTURE TRANSPORT IS INITIALLY FOCUSES WEST OF THE FORECAST AREA
EARLY IN THE EVENING BUT THEN SHIFT EAST INTO THE AREA LATE
TONIGHT INTO EARLY THURSDAY MORNING. WILL HAVE TO KEEP A VERY
CLOSE WATCH ON HOW THIS MOISTURE TRANSPORT EVOLVES
TONIGHT...ESPECIALLY ALONG AND WEST OF THE MISSISSIPPI RIVER. AT
THIS TIME...THINKING SHOWERS AND STORMS WILL PUSH INTO AREAS WEST
OF MISSISSIPPI RIVER BEFORE SUNRISE ON THURSDAY.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 356 AM CDT WED MAY 29 2013
ACTIVE SOUTHWEST FLOW ALOFT ACROSS THE FORECAST AREA WILL PRODUCE
WIDESPREAD SHOWERS AND THUNDERSTORMS ON THURSDAY. SEVERAL EMBEDDED
SHORTWAVES WILL MOVE OVER THE REGION THROUGH THE DAY WITH BROAD
MOISTURE TRANSPORT AND LIFT OVER THE REGION. A STRONGER WAVE MOVES
IN LATE THURSDAY AFTERNOON INTO THURSDAY EVENING...WITH SHOWERS
AND STORM PERSISTING. INSTABILITY IS NOT ALL THAT
IMPRESSIVE...GENERALLY IN THE 500 TO 1000 J/KG RANGE. 0-6 KM SHEAR
LOOKS TO HOVER IN THE 30 TO 40 KT RANGE SO CANNOT RULE OUT A FEW
STRONG TO SEVERE THUNDERSTORMS WITH HEAVY RAINFALL...LARGE HAIL
AND DAMAGING WINDS. THE REPEATED ROUND OF SHOWERS AND STORMS OVER
THE AREA WILL INCREASE FLOODING CONCERNS...ESPECIALLY OVER
NORTHEAST IOWA...SOUTHEAST MINNESOTA AND FAR WESTERN WISCONSIN.
RAINFALL AMOUNTS OF 1 TO 2 INCHES ARE POSSIBLE BY THURSDAY NIGHT.
THE TROUGH FINALLY CLOSES INTO AN UPPER LOW OVER WESTERN NORTH
DAKOTA. DESPITE THE WIDESPREAD SHOWERS AND STORMS ACROSS THE AREA
ON THURSDAY...THE WARM SOUTHERLY FLOW WILL ALLOW HIGH TEMPERATURES
TO WARM INTO THE MID TO UPPER 70S. THE UPPER LOW STARTS TO DRIFT
SOUTHEAST LATE THURSDAY NIGHT INTO FRIDAY AS A VIGOROUS SHORTWAVE
PUSHES THROUGH THE PLAINS AND LIFTS NORTHEAST INTO THE UPPER AND
MID MISSISSIPPI RIVER VALLEY. AS THIS WAVE MOVES IN ON FRIDAY 0-6
KM BULK SHEAR REALLY RAMPS UP FRIDAY AFTERNOON...45 TO 55 KTS
ACROSS MUCH OF THE FORECAST AREA. HOWEVER...A BOUNDARY PUSHES
ACROSS THE AREA LATE THURSDAY NIGHT INTO FRIDAY MORNING PUSHING
THE BEST INSTABILITY JUST SOUTHEAST OF THE FORECAST AREA..ACROSS
PORTIONS OF FAR EASTERN IOWA THROUGH NORTHERN ILLINOIS AND
SOUTHEAST WISCONSIN. CANNOT RULE OUT SEVERE STORMS ON FRIDAY BUT
THE HIGHER CHANCES LOOK TO BE SOUTHEAST OF THE AREA. PORTIONS OF
FAR NORTHEAST IOWA...AND EXTREME SOUTHWEST WISCONSIN COULD BE
IMPACTED. WILL HAVE TO KEEP A VERY CLOSE WATCH OVER THE NEXT FEW
FORECAST MODELS RUNS TO SEE EXACTLY WHERE THE BOUNDARY WILL SET
UP. SHOWER AND THUNDERSTORMS CHANCES CONTINUE INTO SATURDAY AS THE
UPPER LOW DRIFTS ACROSS WISCONSIN. RAIN CHANCES WILL CONTINUE INTO
SUNDAY AS A TROUGH REMAINS OVER THE GREAT LAKES REGION. AN
UNSEASONABLY COLD AIRMASS MOVES INTO THE REGION SUNDAY INTO MONDAY
WITH STANDARDIZED 850 MB TEMPERATURE ANOMALIES OF -1.5. WOULD
EXPECT OVERNIGHT LOWS ON SUNDAY TO FALL INTO THE UPPER 30S OVER
FAR NORTHERN WISCONSIN...FALLING INTO THE LOWER 40S ACROSS CENTRAL
WISCONSIN AND THE UPPER 40S ACROSS NORTHEAST IOWA. LOCATIONS ALONG
AND NORTH OF THE INTERSTATE 94 CORRIDOR COULD SEE SOME AREAS OF
FROST. HIGH PRESSURE SLIDES EAST OF THE REGION LATE MONDAY NIGHT
INTO TUESDAY AS A TROUGH PUSHES THROUGH THE NORTHERN PLAINS. A
WARM FRONT LOOKS TO LIFT INTO THE UPPER MISSISSIPPI RIVER VALLEY
LATE MONDAY NIGHT INTO TUESDAY BRINGING A CHANCE OF SHOWERS AND
THUNDERSTORMS TO THE AREA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 600 AM CDT WED MAY 29 2013
AREAS OF FOG WERE FOUND ACROSS THE REGION EARLY THIS MORNING...WITH
VSBYS BOBBING UP AND DOWN. KRST HAD DROPPED TO 1/4SM AND SHOULD STAY
THERE FOR A COUPLE HOURS BEFORE MIXING HELPS IMPROVE THE VSBY AND
CIG HEIGHTS BY MID/LATE MORNING. KLSE HAS STAYED OUT OF THE SUB 1SM
BR FOR NOW...AND THINK THAT SHOULD PERSIST. CIGS HAVE FLUCTUATED
ABOVE AND BELOW 1 KFT THOUGH...AND THIS TREND WILL LIKELY PERSIST
INTO MID MORNING BEFORE MIXING IMPROVES CONDITIONS HERE TOO.
A WARM FRONT WILL ADVANCE NORTHWARD ACROSS THE REGION TODAY...LIKELY
IN THE 17-18Z TIME FRAME AT KRST/KLSE. THIS COULD BE SLOWED...OR
SPED UP...DEPENDING ON CLEARING AND ON GOING CONVECTION TO THE
SOUTH. CIGS WILL IMPROVE INTO THE VFR RANGE WITH THE PASSAGE OF THE
FRONT...BUT SHRA/TS WILL ALSO INCREASE AROUND AND JUST SOUTH OF IT.
MEANWHILE...AN UPPER AIR DISTURBANCE COULD SPIN OUT OF THE PLAINS
AND ACROSS THE REGION BY LATE AFTERNOON/EARLY EVENING. THIS WOULD
TAP INTO INCREASED INSTABILITY THAT WILL DEVELOP IN THE WAKE OF THE
WARM FRONT...INCREASING THE SHRA/TS POTENTIAL.
THE PCPN CHANCES ARE PROBLEMATIC TO NARROW DOWN TODAY AND TONIGHT
WITH BOUNDARIES AND OTHER MESO FEATURES ALL POTENTIALLY SERVING AS A
FOCUS FOR SHRA/TS. WILL HIGHLIGHT THE FAVORED PERIOD ALONG AND JUST
SOUTH OF THE FRONT FOR THE AFTERNOON HOURS FOR NOW...BUT THIS WILL
HAVE TO BE REFINED LATER IN THE DAY AS WHERE THE PCPN WILL DEVELOP
AND MOVE BECOMES CLEARER.
SHOULD GET A FEW HOURS RAIN FREE TONIGHT...BUT SHRA/TS WILL BECOME
WIDESPREAD FOR THE REGION ON THU AHEAD OF AN APPROACHING COLD FRONT
AND WITHIN THE MAIN AVENUE OF LOW LEVEL MOISTURE TRANSPORT. A RETURN
TO MVFR CONDITIONS IS LIKELY.
&&
.HYDROLOGY...TODAY THROUGH FRIDAY
ISSUED AT 356 AM CDT WED MAY 29 2013
PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED ACROSS MUCH OF THE
REGION THROUGH FRIDAY. THE HEAVIEST RAIN IS EXPECTED TO FALL FROM
THURSDAY INTO FRIDAY. TOTAL RAINFALL FROM TODAY THROUGH FRIDAY
COULD RANGE FROM 1 TO 3 INCHES WITH LOCALLY HIGHER AMOUNTS
POSSIBLE. THIS COULD LEAD TO FLASH FLOODING AS WELL AS RISES AND
POSSIBLE FLOODING ON AREA RIVERS. A FLASH FLOOD WATCH MAY BE
NEEDED FOR THE AREA IF DETAILS BECOME CLEARER ON WHERE AND WHEN
THE HEAVIEST RAIN WILL FALL.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM....WETENKAMP
AVIATION.....RIECK
HYDROLOGY....WETENKAMP
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
940 AM PDT WED MAY 29 2013
...BECOMING MUCH HOTTER AND DRIER BY FRIDAY AND SATURDAY...
.DISCUSSION...AS OF 9:40 AM PDT WEDNESDAY...A RIDGE OF HIGH PRESSURE
IS BUILDING OVER THE EASTERN PACIFIC THIS MORNING. MOISTURE IS
FLOWING OVER THE RIDGE INTO THE FORECAST AREA...THIS IS RESULTING
IN A MIX OF LOW AND MID CLOUDS. THESE CLOUDS SHOULD BEGIN TO
SCATTER OUT BY LATE MORNING RESULTING IN MOSTLY SUNNY TO PARTLY
CLOUDY SKIES.
THE MAIN WEATHER CONCERN FOR THE NEXT SEVERAL DAYS WILL BE THE
POTENTIAL FOR EXCESSIVELY WARM WEATHER THIS WEEKEND. THE
PREVIOUSLY MENTIONED RIDGE OF HIGH PRESSURE IS EXPECTED TO BUILD
AS THE AIRMASS WARMS OVER THE FORECAST AREA. 500MB HEIGHTS ARE
EXPECTED TO REACH 585 DM BY FRIDAY OVER THE SAN FRANCISCO BAY
AREA. AT THE SURFACE A THERMAL TROUGH FORMS OVER THE FORECAST AREA
FRIDAY SLIDING WEST BY SATURDAY...RESULTING IN OFFSHORE FLOW.
850 MB TEMPERATURES ARE EXPECTED TO CLIMB TO 22 DEGREES C SATURDAY
NEAR SAN JOSE WITH 24 DEGREES C EXPECTED IN THE SOUTHERN SALINAS
VALLEY. THE COMBINATION OF THE WARM AIRMASS AND OFFSHORE FLOW WILL
RESULT IN VERY WARM AFTERNOON TEMPERATURES SATURDAY. TEMPERATURES
ALONG THE COAST WILL BE IN THE MID 70S TO NEAR 80S WITH LOCAL
SPOTS SUCH AS SANTA CRUZ REACHING INTO THE UPPER 80S. IN LAND
TEMPERATURES WILL RANGE FROM THE MID 80S TO MID 90S WITH SOME
LOCATIONS IN THE SOUTHERN SALINAS VALLEY REACHING 100 DEGREES.
THE WARM AIRMASS WILL ALSO PROMOTE WARM OVERNIGHT TEMPERATURES...ESPECIALLY
IN THE MOUNTAINS. OVERNIGHT LOW TEMPERATURES WILL ONLY FALL INTO
THE MID 70S OVERNIGHT IN THE MOUNTAINS WHICH WILL ALSO PROMOTE
POOR RELATIVE HUMIDITY RECOVERIES. THE POOR RELATIVE HUMIDITY
RECOVERIES WILL RAISE FIRE CONCERNS...DRYING FUELS WITH OFFSHORE
WINDS.
THE NEXT HURTLE WILL BE DETERMINING HOW LONG THE WARM TEMPERATURES
WILL LAST...ESPECIALLY ALONG THE COAST. THE 1200Z RUN OF THE GFS
40 INDICATES THAT A SOUTHERLY SURGE WILL BE POSSIBLE SUNDAY WHICH
WOULD MOST LIKELY RESULT IN SUBSTANTIAL COOLING ALONG THE COAST.
HOWEVER...850 MB TEMPERATURES REMAIN NEAR 25 DEGREES C INLAND
SUNDAY WHICH WOULD CONTINUE TO SUPPORT HOT INLAND TEMPERATURES.
&&
.AVIATION...AS OF 4:40 AM PDT WEDNESDAY...POSSIBLE MVFR CIGS
THROUGH 18Z. LOW CONFIDENCE. MOST OF THE SHORT TERM MODELS KEEP
THE TERMINALS AT VFR...HOWEVER...THE HRRR AND CURRENT SATELLITE
TRENDS INDICATE STRATUS MAY IMPACT THE REGION THROUGH AT LEAST
18Z. OTHERWISE...MODERATE ONSHORE FLOW THIS AFTERNOON WITH LIKELY
RETURN OF MVFR AND POSSIBLE IFR CIGS AROUND MIDNIGHT.
VICINITY OF KSFO...POSSIBLE MVFR CIGS THROUGH THE EARLY MORNING
HOURS. VERY LOW CONFIDENCE. MODERATE ONSHORE FLOW THIS
AFTERNOON...WITH WESTERLY WIND GUSTS TO 25 KT.
KSFO BRIDGE APPROACH...THE APPROACH MAY BE IMPACTED BY PATCHY
STRATUS AN HOUR LATER THAN THE TERMINAL.
MONTEREY BAY AREA TERMINALS...MVFR CIGS THROUGH 19Z...LOW CONFIDENCE.
STRATUS LOOKS TO BE FILLING IN QUICKLY AND IS FORECAST TO PERSIST
THROUGH THE LATE MORNING HOURS. MODERATE ONSHORE FLOW THIS
AFTERNOON WITH A RETURN OF STRATUS JUST BEFORE MIDNIGHT.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...SCA...SF BAY FROM 2 PM
SCA...MRY BAY FROM 2 PM
SCA...PIGEON PT TO PT PINOS 0-10 NM FROM 2 PM
SCA...PT ARENA TO PT REYES 0-10 NM FROM 2 PM
SCA...PT REYES TO PIGEON PT 0-10 NM FROM 2 PM
SCA...PT ARENA TO PIGEON PT 10-60 NM FROM 2 PM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM FROM 2 PM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
&&
$$
PUBLIC FORECAST: LARRY
AVIATION/MARINE: RILEY
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.SANFRANCISCOBAYAREA.GOV
WWW.TWITTER.COM/NWSBAYAREA
WWW.YOUTUBE.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS NEW YORK NY
145 PM EDT WED MAY 29 2013
.SYNOPSIS...
A WARM FRONT PUSHES NORTH THROUGH THE REGION TODAY...WITH HIGH
PRESSURE BUILDING IN ITS WAKE. A BERMUDA HIGH DOMINATES OUR
WEATHER THURSDAY NIGHT THROUGH SATURDAY NIGHT. A PRE-FRONTAL
TROUGH MOVES INTO THE REGION SUNDAY...FOLLOWED BY A COLD FRONT
APPROACHING FROM THE WEST SUNDAY NIGHT...THEN CROSSING THE TRI-
STATE ON MONDAY. CANADIAN HIGH PRESSURE THEN BUILDS IN MONDAY
NIGHT AND TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE WARM FRONT IS A LITTLE SLOWER PROGRESSING NORTHWARD THAN
PREVIOUSLY FORECAST...BUT STILL THINK IT SHOULD PASS NORTH OF THE
REGION IN THE NEXT FEW HOURS. CLOUD COVER CONTINUES TO ERODE AND
BEGINNING TO SEE TEMPERATURES RISE WITH WARM ADVECTION TAKING
PLACE WITH INCREASING SOUTHWEST FLOW. ADJUSTED HIGH TEMPERATURES
DOWN A FEW DEGREES DUE TO SLOWER PROGRESSION OF FRONT AND
LINGERING CLOUD COVER.
FOCUS THEN SHIFTS TO THE POSSIBILITY OF CONVECTION THIS AFTERNOON.
INSTABILITY INCREASING ACROSS THE INTERIOR AND LOWER HUDSON
VALLEY AS CLOUDS ERODE AND HEATING TAKES PLACE. SPC MESOANALYIS IS
SHOWING 500 TO 1000 J/KG OF MLCAPE WITH LATEST RAP FCST INCREASING
CAPES SOME MORE AS THE AFTERNOON PROGRESSES. LAST SEVERAL RUNS OF
THE HRRR MODEL HAVE BEEN SHOWING A CLUSTER OF STORMS MOVING IN TO
OUR NW COUNTIES AROUND 21Z AND SHIFTING EASTWARD THROUGH 00Z. USED
THIS IDEA FOR UPDATING POP GRIDS WITH LIKELIHOOD ACROSS LOWER
HUDSON VALLEY AND INTERIOR CONNECTICUT WITH CHANCE POPS FURTHER
SOUTH. CONFIDENCE IN SEVERE POTENTIAL REMAINS LOW...BUT PORTIONS OF
AREA REMAIN IN A SLIGHT RISK. THE MAIN THREATS APPEAR TO BE
DAMAGING WINDS AND HAIL. PW VALUES AROUND 1.6 COULD ALSO LEAD TO
THE POSSIBILITY OF A PERIOD OF HEAVY RAIN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
THE THREAT FOR THUNDERSTORMS...ESP SEVERE...DIMINISHES QUICKLY
AFTER SUNSET WITH THE LOSS OF DAYTIME HEATING. KEPT THE MENTION OF
LINGERING ISO TO SCT THUNDERSTORMS IN THROUGH 06Z...THEN HAVE
DRYING OUT AS THE BERMUDA HIGH PUSHES INTO THE REGION...AND
SUBSIDENCE BEGINS TO DOMINATE ALOFT. THE PERSISTENT SOUTHWESTERLY
FLOW DOES KEEP WARM...MOIST AIR IN THE AREA...SO PATCHY FOG WILL
BE POSSIBLE AGAIN TONIGHT WITH LIGHT WINDS.
HIGH PRESSURE CONTINUES TO IMPACT THE REGION THROUGH THE DAY
THURSDAY...PRODUCING GENERALLY QUIET CONDITIONS.
HOWEVER...EXPECTING A VERY WARM DAY WITH TEMPS WELL ABOVE NORMAL
REACHING NEAR 90 OVER THE NYC METRO AREA...AND INTO THE MID TO
UPPER 80S ELSEWHERE. SEA BREEZE DEVELOPMENT IS EXPECTED DURING THE
AFTN WHICH COULD HELP KEEP THE COASTS SLIGHTLY COOLER. THESE WARM
TEMPS COMBINED WITH THE VERY MOIST AIR WILL PUSH INSTABILITY
VALUES INLAND UP TO AROUND 1000 J/KG AGAIN. HAVE INCLUDED A SLIGHT
CHC OF TSTORMS OVER THIS AREA...WITH PSBL DIURNAL DEVELOPMENT.
TEMP GUIDANCE MORE IN LINE FOR LOWS TONIGHT...AND HIGHS
TOMORROW...SO CHOSE A BLEND OF THE MET/MAV.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
NAM/GFS/ECMWF FAIRLY SIMILAR THURSDAY NIGHT-FRIDAY NIGHT SO USED A
BLEND. DEEP LAYERED RIDGING BUILDS IN DURING THIS TIME FRAME -
ALLOWING FOR DRY AND UNSEASONABLY WARM TO HOT CONDITIONS. THE GFS
WAS ALONE IN SUGGESTING AIR MASS CONVECTION FRIDAY
AFTERNOON/EVENING...SO GIVEN SUBSIDENCE UNDER THE RIDGE...DID NOT
FORECAST.
GFS/ECMWF REMAIN FAIRLY SIMILAR WITH LARGE SCALE FEATURES
SATURDAY-TUESDAY...WHILE CMC REMAINS SLOW OUTLIER. USED ECMWF/GFS
BLEND IN THIS TIME FRAME DUE TO REASONABLE AGREEMENT.
RIDGE AXIS SLIDES TO THE EAST SATURDAY AND SATURDAY NIGHT...SO HAVE
SLIGHT CHANCE POPS FOR SHRA/TSRA OVER FAR NW ZONES SATURDAY
AFTERNOON/EARLY EVENING TO REFLECT POTENTIAL FOR DIURNAL CONVECTION
FARTHEST AWAY FROM THE RIDGE AXIS. OTHERWISE IT SHOULD BE DRY
THROUGH SATURDAY NIGHT. COULD SEE SOME PATCHY FOG LATE SATURDAY
NIGHT OVER EASTERN SECTIONS.
POTENTIAL FOR PASSING SHORTWAVE IN SW FLOW ALOFT...ALONG WITH A
PRE-FRONTAL TROUGH MOVING IN WESTERN ZONES WARRANTS CHANCE POPS NW
1/2 AND SLIGHT CHANCE POPS SE 1/2 OF THE CWA SUNDAY. APPROACHING
700-500 HPA SHORTWAVE SUNDAY NIGHT THAT MOVES THROUGH ON
MONDAY...ALONG WITH ASSOCIATED COLD FRONT AT THE SURFACE...WARRANTS
CHANCE POPS FOR SHRA/TSRA BOTH PERIODS. GIVEN ANTICIPATED STRENGTH
OF FRONT...CANNOT RULE OUT ISOLATED STRONG TO POSSIBLY SEVERE STORMS
ON MONDAY. ALSO COULD SEE SOME PATCHY FOG AGAIN LATE SUNDAY NIGHT
OVER EASTERN SECTIONS.
DEEP UPPER TROUGH BUILDS IN OVER THE NE US/MID ATLANTIC STATES
MONDAY NIGHT AND TUESDAY. FORCING FROM ARRIVING TROUGH WARRANTS A
CHANCE OF SHOWERS IN THE EVENING...TAPERING OF TO DRY CONDITIONS BY
TUESDAY MORNING FROM NW TO SE.
FOR TEMPERATURES IN THE LONG TERM...
FOR LOWS THURSDAY NIGHT USED A MAV/MET BLEND WITH VALUES AROUND 10
DEGREES ABOVE NORMAL. USED A BLEND OF MAV/MET GUIDANCE WITH NAM
2-METER TEMPERATURES AND A MIX DOWN FROM 825 HPA PER BUFKIT
SOUNDINGS FOR HIGHS ON FRIDAY WITH VALUES AROUND 15 DEGREES ABOVE
NORMAL - MAINLY FROM THE UPPER 80S TO LOWER 90S - EXCEPT FROM AROUND
80-MID 80S NEAR THE IMMEDIATE COAST AND THE TWIN FORKS OF LONG
ISLAND.
USED A BLEND OF MEX/MEX ENSEMBLE MEAN/ECE/WPC GUIDANCE FOR
TEMPERATURES FRIDAY NIGHT-TUESDAY. WELL ABOVE NORMAL TEMPERATURES
ARE EXPECTED THROUGH SUNDAY...THOUGH WILL SEE TEMPERATURES LOWER A
TAD EACH DAY. TEMPERATURES SHOULD BE NEAR NORMAL ON MONDAY...THEN
BELOW NORMAL ON TUESDAY.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
A WARM FRONT WILL CONTINUE TO MOVE THROUGH THE AREA THIS AFTERNOON.
MAINLY VFR THROUGH THE TAF PERIOD. ANY SHRA/TSTORMS THAT OCCUR AT
THE TERMINALS WILL LIKELY LOWER THE CIGS/VIS...POSSIBLY TO IFR FOR
A BRIEF TIME. MODERATE CONFIDENCE ON THE SW WINDS THROUGH THE
AFTERNOON WITH A SEA BREEZE COMPONENT AT KJFK AND KISP.
TSTM DEVELOPMENT IS POSSIBLE N AND W OF THE CITY IN THE AFTN. HIGHEST
POTENTIAL IS AT KSWF/KHPN/KBDR AND USED A TEMPO GROUP. ADDED VCTS
TO LGA SHOWING THAT SOME TSTORMS MAY MAKE IT THAT FAR SOUTH BUT
THERE IS STILL UNCERTAINTY REGARDING THE COVERAGE OF THE STORMS.
COULD ALSO SEE LINGERING SHOWERS OVER LONG ISLAND LATE THIS
EVENING BUT CONFIDENCE TOO LOW TO INCLUDE AT THIS TIME.
FOG POSSIBLE TONIGHT...MAINLY AT COASTAL TERMINALS. WITH 5-10KT
WINDS...COULD BE PATCHY IN NATURE. DID NOT GO IFR TONIGHT BUT THIS
MAY NEED TO BE RE-EVALUATED.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KEWR FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED FOR ANY SHRA/TSRA
THIS AFTERNOON.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KJFK FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED FOR ANY SHRA/TSRA
THIS AFTERNOON.
KLGA FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED FOR ANY SHRA/TSRA
THIS AFTERNOON.
KTEB FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED FOR ANY SHRA/TSRA
THIS AFTERNOON.
KHPN FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED FOR ANY SHRA/TSRA
THIS AFTERNOON.
KISP FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED FOR ANY SHRA/TSRA
THIS AFTERNOON.
.OUTLOOK FOR 18Z THURSDAY THROUGH MONDAY...
.THURSDAY-FRIDAY...MAINLY VFR.
.FRIDAY NIGHT-SATURDAY...MVFR FOG/STRATUS POSSIBLE OVER EASTERN
TERMINALS LATE AT NIGHT/EARLY IN THE MORNING. SLIGHT CHANCE OF
AFTERNOON/EARLY EVENING SHRA/TSRA FROM CITY TERMINALS ON N AND W.
.SATURDAY NIGHT...MAINLY VFR.
.SUNDAY-MONDAY...MVFR OR LOWER POSSIBLE IN SHRA/TSRA.
&&
.MARINE...
WITH PERSISTENT SOUTHWESTERLY FLOW THROUGH TONIGHT...ISSUED SCA FOR
OCEAN WATERS TONIGHT WITH GREATER CONFIDENCE IN SEEING SEAS
AROUND 5 FT THROUGH THE EARLY MORNING HOURS. OTHERWISE...EXPECTING
SUB-SCA CONDITIONS LASTING THROUGH THURSDAY.
SUB-SCA CONDITIONS ARE EXPECTED OVER NEW YORK HARBOR...LONG ISLAND
SOUND AND THE BAYS OF LONG ISLAND THURSDAY NIGHT THROUGH SATURDAY
NIGHT. ON THE OCEAN A PERSISTENT SW-S SWELL AND SW FLOW COULD BUILD
SEAS TO SCA LEVELS MAINLY THIS WEEKEND.
GUSTS TO 25 KT ARE POSSIBLE ON ALL WATERS ON SUNDAY.
&&
.HYDROLOGY...
QPF BETWEEN 1/4 AND 1/2 INCH EXPECTED THROUGH THIS AFTERNOON.
SOME LOCALLY HEAVIER AMOUNTS ARE POSSIBLE IN ANY EMBEDDED
CONVECTION LATE TONIGHT. TSTM DEVELOPMENT WED AFTERNOON COULD ALSO
PRODUCE LOCAL DOWNPOURS.
WIDESPREAD SIGNIFICANT PRECIPITATION OF 1/2 INCH OR MORE IS NOT
EXPECTED THROUGH THE UPCOMING WEEKEND. HOWEVER...ANY STRONGER
CONVECTION COULD PRODUCE LOCALLY HEAVY RAINFALL SATURDAY THROUGH
MONDAY...WHICH COULD RESULT IN LOCALIZED MINOR POOR DRAINAGE/URBAN
FLOODING.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 6 PM THIS EVENING
TO 6 AM EDT THURSDAY FOR ANZ350-353-355.
&&
$$
SYNOPSIS...MALOIT/SEARS
NEAR TERM...SEARS/DS
SHORT TERM...SEARS
LONG TERM...MALOIT
AVIATION...LN
MARINE...MALOIT/SEARS/DS
HYDROLOGY...MALOIT/SEARS
AREA FORECAST DISCUSSION
NWS ALBANY NY
136 PM EDT WED MAY 29 2013
.SYNOPSIS...
A WARM FRONT WILL MOVE THROUGH REGION EARLY IN THE AFTERNOON. A
DISTURBANCE WILL MOVE IN SHORTLY THEREAFTER PRODUCING SCATTERED
SHOWERS AND THUNDERSTORMS. SOME OF THE STORMS MIGHT GET STRONG TO
LOCALLY SEVERE...PRODUCING GUSTY WIND AND POSSIBLY LARGE HAIL. ONCE
THIS DISTURBANCE MOVES BY TONIGHT...THE THREAT OF THUNDERSTORMS WILL
DIMINISH AND IT WILL TURN RATHER HOT FOR THE REST OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
SEVERE THUNDERSTORMS STILL POSSIBLE THIS AFTERNOON INTO THIS
EVENING...
AS OF 1230 PM EDT...ISENTROPIC LIFT HAD ALL BUT MOVE NORTH OF THE
REGION. STILL SOME SHOWERS EXITING THE BERKSHIRES. THE SURFACE WARM
FRONT WAS NOT FAR AWAY...ABOUT TO WORK INTO OUR REGION. CLEARING WAS
ACTUALLY AHEAD OF SURFACE FRONT AND BASED ON SATELLITE
PICTURES...MUCH OF OUR AREA LOOKS TO RECEIVE SUNSHINE BY EARLY
AFTERNOON.
SO THE HEATING IS ON...ALTHOUGH TEMPERATURES WERE STILL ONLY IN THE
60S IN THE HUDSON VALLEY...STILL WEDGED IN A MARINE LAYER.
HOWEVER...BASED ON WHAT IS HAPPENING UPSTREAM...WE BELIEVE THIS
MARINE LAYER WILL ERODE AWAY WITH TIME.
EXPECT INSTABILITY TO RAMP DURING THE AFTERNOON HOURS WHICH SHOULD
LEAD TO SCATTERED SHOWERS AND STORMS AS DISTURBANCE OVER THE GREAT
LAKES WORK INTO OUR REGION DURING THE AFTERNOON. THIS ALL WILL LEAD
TO THOSE SCATTERED SHOWERS AND THUNDERSTORMS.
LAPS DATA ALREADY INDICATED SBCAPES NEAR 500 J/KG TO THE WEST OF THE
HUDSON VALLEY.
FOR THIS UPDATE...DID SCALE BACK COVERAGE TO SCATTERED (AS THE NEW
NAM12 INDICATED LESS COVERAGE) BUT CERTAINLY KEPT ALL THE STRONG
WORDING IN (POSSIBLE DAMAGING WIND/LARGE HAIL AND HEAVY RAINFALL).
RE-TOOLED HOURLY GRIDS LOWERING CURRENT TEMPERATURES BUT NOT
TOUCHING AFTERNOON HIGH TEMPERATURES. ALSO...ACTUALLY DECREASED
CLOUD A LITTLE AND AGAIN SCALED BACK FROM 60 POPS TO 50 (SCATTERED
COVERAGE).
THE NAM12...LOCAL HIRES WRF AND 3KM HRRR STILL ALL INDICATED
CONVECTION DEVELOPING ACROSS WESTERN AND CENTRAL NY DURING THE
EARLY AFTN. THIS ACTIVITY WILL SPREAD INTO OUR AREA FOR THE MID
AFTERNOON THROUGH THE EVENING HOURS.
THERE ARE SEVERAL FACTORS WHICH POINT TO THE POTENTIAL FOR SEVERE
THUNDERSTORMS. BECAUSE OF THE STRENGTH OF THE LLJ...0-6 KM BULK SHEAR
WITH BE AROUND 30-40 KTS. 0-3 KM HELICITY VALUES ARE EXPECTED TO
BE AROUND 200 M2/S2 AND 0-1 KM HELICITY VALUES ARE ALSO VERY
IMPRESSIVE...WITH 100-200 M2/S2 BY EVENING. WHILE MID LEVEL LAPSE
RATES AREN/T OVERLY STRONG...VALUES OF 6-6.5 DEGREES C/KM WILL BE
SUFFICIENT FOR PRODUCING UPDRAFTS CAPABLE OF SEVERE WIND/HAIL.
WHILE THE MAIN THREAT WILL BE DAMAGING WINDS...THE IMPRESSIVE
HELICITY VALUES AND THE FACT THAT THIS SAME SYSTEM PRODUCED
TORNADOES LAST EVENING JUST UPSTREAM ACROSS LOWER MICHIGAN WOULD
POINT TO THE POTENTIAL FOR AN ISOLATED TORNADO OR TWO. THE
NAM12/GFS/AND ECMWF ALL DID SHOW SIGNIFICANT TORNADO PARAMETERS IN
EXCESS OF 1 AT SOME LOCATION IN OUR AREA...SO THE TORNADIC
POTENTIAL SHOULD NOT BE IGNORED. SPC AGREES WITH THIS ASSESSMENT
AND HAS OUR AREA IN A SLIGHT RISK...WITH A 5% PROBABILITY FOR A
TORNADO WITHIN 25 MI OF ANY PARTICULAR LOCATION.
THE MAIN INHIBITING FACTOR WILL BE HAVING ENOUGH INSTABILITY...BUT
EVEN THAT MIGHT NOT BE SOME MUCH OF AN INHIBITOR AS THERE ARE PLENTY
OF BREAKS OF SUNSHINE UPSTREAM AT THIS TIME.
MAX TEMPS THIS AFTERNOON WILL RANGE FROM THE MID 70S TO LOW 80S.
WITH THE LOSS OF HEATING...AND WITH THE SHORTWAVE MOVING TO THE
EAST OF THE AREA...THUNDERSTORM POTENTIAL WILL DIMINISH BY LATE
THIS EVENING. IT SHOULD CLEAR OUT...ALTHOUGH THERE WILL BE
POTENTIAL FOR PATCHY FOG IN THOSE AREAS THAT RECEIVE RAINFALL. MIN
TEMPS WILL BE IN THE 50S TO LOW 60S.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
WARM AND MUGGY WEATHER IS EXPECTED FOR THE SHORT TERM PERIOD AS
OUR REGION WILL BE DOMINATED BY A STRONG RIDGE AT 500 HPA CENTERED
OVER THE MID ATLANTIC REGION. 850 HPA TEMPS WILL SURGE TO 16-18
DEGREES C...SO MAX TEMPS WILL REACH THE UPPER 80S TO LOW 90S FOR
BOTH THURSDAY AND FRIDAY. OVERNIGHT LOWS WILL BE WARM AND
STICKY...WITH MAINLY UPPER 50S TO MID 60S AT NIGHT.
WHILE IT SHOULD BE WARM ENOUGH ALOFT TO KEEP A CAP ON ANY
CONVECTION...WE WILL GO WITH A SLIGHT CHC FOR A SHOWER OR
THUNDERSTORM ON THURSDAY AFTN IN CASE ANYTHING IS ABLE TO DEVELOP.
FRIDAY LOOKS EVEN MORE CAPPED...SO WE WILL KEEP THE FORECAST
COMPLETELY DRY FOR FRIDAY WITH A MOSTLY SUNNY TO PARTLY SUNNY SKY.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
HEAT CONTINUES INTO THE FIRST PART OF THE WEEKEND WITH HIGHS
SATURDAY WELL IN THE 80S TO NEAR 90. COLD FRONT AND AMPLIFYING
NORTHERN STREAM UPPER ENERGY APPROACH SUNDAY...TRACKING THROUGH OUR
REGION THE BEGINNING OF THE WEEK...WITH EXACT TIMING TO BE
DETERMINED. SINCE THE EXACT TIMING IS UNKNOWN...INCREASING CHANCES
FOR SHOWERS AND THUNDERSTORMS SUNDAY AND SUNDAY NIGHT...BUILDING
INTO THE MID HUDSON VALLEY AND WESTERN NEW ENGLAND LATER SUNDAY
NIGHT AND MONDAY. DRYING AND COOLING EXPECTED ONCE THE FRONT
EXITS...MONDAY NIGHT AND TUESDAY.
SOME STRONG THUNDERSTORMS ARE POSSIBLE SUNDAY AFTERNOON THROUGH
MONDAY AFTERNOON..DEPENDING ON THE EXACT TIMING OF THE FRONT. THERE
IS A DECENT CONSENSUS FOR A NOTICEABLE COOL DOWN AFTER THE FRONTAL
PASSAGE. HIGHS SUNDAY IN THE UPPER 70S TO MID 80S...COOLING TO HIGHS
IN THE UPPER 60S TO MID 70S MONDAY AND MID 60S TO LOWER 70S TUESDAY.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
CEILINGS AND VISIBILITIES WILL BE MAINLY VFR...THROUGH THE
AFTERNOON AND INTO THE EVENING AS A WARM FRONT TRACKS THROUGH THE
REGION. SOME ORGANIZED THUNDERSTORM ACTIVITY IS POSSIBLE DURING THE
LATE AFTERNOON AND EARLY EVENING HOURS. THIS CONVECTION WOULD LIKELY
RESULT IN MVFR CIGS AND VSBYS AS WELL AS INCREASED WINDS. HAVE
INDICATED A TEMPO GROUP AT ALL TAF SITES WITH WINDS 25020G35 KTS.
THE ORGANIZED CONVECTION IS EXPECTED TO MOVE OUT BY MID EVENING...
SO JUST INDICATING VCSH AFTER 00Z. AFTER 06Z EXPECT SOME FOG WITH
MAINLY MVFR CONDITIONS...EXCEPT LIFR AT KGFL.
THU MORNING FA WILL BE CLEARLY IN THE WARM SECTOR WITH MAINLY P6M
BKN035 CONDITIONS EXPECTED THROUGH 18Z THU.
WINDS WILL BE SOUTHWEST AT LESS THAN 10 KTS AT MOST TAF SITES
THROUGH THIS EVENING EXCEPT HIGHER GUSTS IN CONVECTION AS MENTIONED
EARLIER. WINDS WILL BE LIGHT AND VARIABLE OVERNIGHT AND THEN
WEST AROUND 10 KTS ON THURSDAY.
OUTLOOK...
THU-SAT...VFR/MVFR. SLIGHT CHC PM -TSRA EACH DAY. LATE NIGHT AND/OR
EARLY MORNING MVFR/IFR ASSOC WITH FOG POSSIBLE.
SUN-MON...VFR/MVFR. CHC -SHRA/-TSRA.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS OVER THE NEXT SEVERAL DAYS. A WETTING
RAINFALL OCCURRED IN MOST AREAS EARLY THIS MORNING AND ADDITIONAL
SHOWERS AND THUNDERSTORMS ARE POSSIBLE TODAY INTO THIS EVENING.
RH VALUES WILL ONLY DROP TO 55 TO 70 PERCENT TODAY. S-SW WINDS AT
5-15 MPH ARE EXPECTED TODAY.
W-SW WINDS WILL BE AROUND 5-10 MPH TONIGHT WITH RH VALUES RECOVERING
TO NEAR 100 PERCENT. AN ISOLATED SHOWER OR THUNDERSTORM IS POSSIBLE
TOMORROW WITH RH VALUES DROPPING 40 TO 55 PERCENT TOMORROW AFTERNOON.
&&
.HYDROLOGY...
NO WIDESPREAD HYDROLOGIC CONCERNS OVER THE NEXT FIVE DAYS ACROSS
THE HSA.
SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS THE REGION TODAY. PWAT
VALUES WILL BE ABOVE NORMAL...WITH VALUES UP TO 1.75 INCHES...SO
ANY SHOWER OR THUNDERSTORM IS CAPABLE OF PRODUCING TORRENTIAL
DOWNPOURS. ALTHOUGH WIDESPREAD RIVER FLOODING IS NOT
EXPECTED...SMALL STREAM...POOR DRAINAGE...OR URBAN FLOODING WILL
BE POSSIBLE DEPENDING ON THE EXACT TRACK OF SHOWERS AND
THUNDERSTORMS...ESPECIALLY IF SEVERAL THUNDERSTORMS TRACK OVER THE
SAME LOCATION. 3 HR FFG FROM THE NERFC IS AROUND 2-3 INCHES.
ISOLATED SHOWERS OR THUNDERSTORMS ARE POSSIBLE ON THURSDAY
AFTERNOON. OTHERWISE...IT WILL BE FAIRLY DRY THROUGH THE END OF
THE WORK WEEK. ADDITIONAL SHOWERS OR THUNDERSTORMS ARE POSSIBLE
OVER THE WEEKEND.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...FRUGIS
LONG TERM...NAS
AVIATION...11
FIRE WEATHER...FRUGIS
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS ALBANY NY
1230 PM EDT WED MAY 29 2013
.SYNOPSIS...
SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A WARM FRONT
WILL MOVE THROUGH THE REGION THIS MORNING...ESPECIALLY FOR AREAS TO
THE NORTH OF INTERSTATE 90. AS AN UPPER LEVEL DISTURBANCE MOVES
CLOSE TO THE REGION...SOME STRONG THUNDERSTORMS ARE POSSIBLE THIS
AFTERNOON THROUGH THIS EVENING. MUCH WARMER TEMPERATURES AND MUGGY
CONDITIONS ARE EXPECTED FOR THE REMAINDER OF THE WEEK...WITH SOME
ADDITIONAL THUNDERSTORMS POSSIBLE OVER THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
SEVERE THUNDERSTORMS STILL POSSIBLE THIS AFTERNOON INTO THIS
EVENING...
AS OF 1230 PM EDT...ISENTROPIC LIFT HAD ALL BUT MOVE NORTH OF THE
REGION. STILL SOME SHOWERS EXITING THE BERKSHIRES. THE SURFACE WARM
FRONT WAS NOT FAR AWAY...ABOUT TO WORK INTO OUR REGION. CLEARING WAS
ACTUALLY AHEAD OF SURFACE FRONT AND BASED ON SATELLITE
PICTURES...MUCH OF OUR AREA LOOKS TO RECEIVE SUNSHINE BY EARLY
AFTERNOON.
SO THE HEATING IS ON...ALTHOUGH TEMPERATURES WERE STILL ONLY IN THE
60S IN THE HUDSON VALLEY...STILL WEDGED IN A MARINE LAYER.
HOWEVER...BASED ON WHAT IS HAPPENING UPSTREAM...WE BELIEVE THIS
MARINE LAYER WILL ERODE AWAY WITH TIME.
EXPECT INSTABILITY TO RAMP DURING THE AFTERNOON HOURS WHICH SHOULD
LEAD TO SCATTERED SHOWERS AND STORMS AS DISTURBANCE OVER THE GREAT
LAKES WORK INTO OUR REGION DURING THE AFTERNOON. THIS ALL WILL LEAD
TO THOSE SCATTERED SHOWERS AND THUNDERSTORMS.
LAPS DATA ALREADY INDICATED SBCAPES NEAR 500 J/KG TO THE WEST OF THE
HUDSON VALLEY.
FOR THIS UPDATE...DID SCALE BACK COVERAGE TO SCATTERED (AS THE NEW
NAM12 INDICATED LESS COVERAGE) BUT CERTAINLY KEPT ALL THE STRONG
WORDING IN (POSSIBLE DAMAGING WIND/LARGE HAIL AND HEAVY RAINFALL).
RE-TOOLED HOURLY GRIDS LOWERING CURRENT TEMPERATURES BUT NOT
TOUCHING AFTERNOON HIGH TEMPERATURES. ALSO...ACTUALLY DECREASED
CLOUD A LITTLE AND AGAIN SCALED BACK FROM 60 POPS TO 50 (SCATTERED
COVERAGE).
THE NAM12...LOCAL HIRES WRF AND 3KM HRRR STILL ALL INDICATED
CONVECTION DEVELOPING ACROSS WESTERN AND CENTRAL NY DURING THE
EARLY AFTN. THIS ACTIVITY WILL SPREAD INTO OUR AREA FOR THE MID
AFTERNOON THROUGH THE EVENING HOURS.
THERE ARE SEVERAL FACTORS WHICH POINT TO THE POTENTIAL FOR SEVERE
THUNDERSTORMS. BECAUSE OF THE STRENGTH OF THE LLJ...0-6 KM BULK SHEAR
WITH BE AROUND 30-40 KTS. 0-3 KM HELICITY VALUES ARE EXPECTED TO
BE AROUND 200 M2/S2 AND 0-1 KM HELICITY VALUES ARE ALSO VERY
IMPRESSIVE...WITH 100-200 M2/S2 BY EVENING. WHILE MID LEVEL LAPSE
RATES AREN/T OVERLY STRONG...VALUES OF 6-6.5 DEGREES C/KM WILL BE
SUFFICIENT FOR PRODUCING UPDRAFTS CAPABLE OF SEVERE WIND/HAIL.
WHILE THE MAIN THREAT WILL BE DAMAGING WINDS...THE IMPRESSIVE
HELICITY VALUES AND THE FACT THAT THIS SAME SYSTEM PRODUCED
TORNADOES LAST EVENING JUST UPSTREAM ACROSS LOWER MICHIGAN WOULD
POINT TO THE POTENTIAL FOR AN ISOLATED TORNADO OR TWO. THE
NAM12/GFS/AND ECMWF ALL DID SHOW SIGNIFICANT TORNADO PARAMETERS IN
EXCESS OF 1 AT SOME LOCATION IN OUR AREA...SO THE TORNADIC
POTENTIAL SHOULD NOT BE IGNORED. SPC AGREES WITH THIS ASSESSMENT
AND HAS OUR AREA IN A SLIGHT RISK...WITH A 5% PROBABILITY FOR A
TORNADO WITHIN 25 MI OF ANY PARTICULAR LOCATION.
THE MAIN INHIBITING FACTOR WILL BE HAVING ENOUGH INSTABILITY...BUT
EVEN THAT MIGHT NOT BE SOME MUCH OF AN INHIBITOR AS THERE ARE PLENTY
OF BREAKS OF SUNSHINE UPSTREAM AT THIS TIME.
MAX TEMPS THIS AFTERNOON WILL RANGE FROM THE MID 70S TO LOW 80S.
WITH THE LOSS OF HEATING...AND WITH THE SHORTWAVE MOVING TO THE
EAST OF THE AREA...THUNDERSTORM POTENTIAL WILL DIMINISH BY LATE
THIS EVENING. IT SHOULD CLEAR OUT...ALTHOUGH THERE WILL BE
POTENTIAL FOR PATCHY FOG IN THOSE AREAS THAT RECEIVE RAINFALL. MIN
TEMPS WILL BE IN THE 50S TO LOW 60S.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
WARM AND MUGGY WEATHER IS EXPECTED FOR THE SHORT TERM PERIOD AS
OUR REGION WILL BE DOMINATED BY A STRONG RIDGE AT 500 HPA CENTERED
OVER THE MID ATLANTIC REGION. 850 HPA TEMPS WILL SURGE TO 16-18
DEGREES C...SO MAX TEMPS WILL REACH THE UPPER 80S TO LOW 90S FOR
BOTH THURSDAY AND FRIDAY. OVERNIGHT LOWS WILL BE WARM AND
STICKY...WITH MAINLY UPPER 50S TO MID 60S AT NIGHT.
WHILE IT SHOULD BE WARM ENOUGH ALOFT TO KEEP A CAP ON ANY
CONVECTION...WE WILL GO WITH A SLIGHT CHC FOR A SHOWER OR
THUNDERSTORM ON THURSDAY AFTN IN CASE ANYTHING IS ABLE TO DEVELOP.
FRIDAY LOOKS EVEN MORE CAPPED...SO WE WILL KEEP THE FORECAST
COMPLETELY DRY FOR FRIDAY WITH A MOSTLY SUNNY TO PARTLY SUNNY SKY.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
HEAT CONTINUES INTO THE FIRST PART OF THE WEEKEND WITH HIGHS
SATURDAY WELL IN THE 80S TO NEAR 90. COLD FRONT AND AMPLIFYING
NORTHERN STREAM UPPER ENERGY APPROACH SUNDAY...TRACKING THROUGH OUR
REGION THE BEGINNING OF THE WEEK...WITH EXACT TIMING TO BE
DETERMINED. SINCE THE EXACT TIMING IS UNKNOWN...INCREASING CHANCES
FOR SHOWERS AND THUNDERSTORMS SUNDAY AND SUNDAY NIGHT...BUILDING
INTO THE MID HUDSON VALLEY AND WESTERN NEW ENGLAND LATER SUNDAY
NIGHT AND MONDAY. DRYING AND COOLING EXPECTED ONCE THE FRONT
EXITS...MONDAY NIGHT AND TUESDAY.
SOME STRONG THUNDERSTORMS ARE POSSIBLE SUNDAY AFTERNOON THROUGH
MONDAY AFTERNOON..DEPENDING ON THE EXACT TIMING OF THE FRONT. THERE
IS A DECENT CONSENSUS FOR A NOTICEABLE COOL DOWN AFTER THE FRONTAL
PASSAGE. HIGHS SUNDAY IN THE UPPER 70S TO MID 80S...COOLING TO HIGHS
IN THE UPPER 60S TO MID 70S MONDAY AND MID 60S TO LOWER 70S TUESDAY.
&&
.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
ANOTHER AREA OF SHOWERS ASSOCIATED WITH AN OLD WEAKENING CONVECTIVE
COMPLEX SHOULD TRACK THROUGH THE REGION THROUGH ABOUT 16Z...REDUCING
CEILINGS AND VISIBILITIES TO PERIODS OF MVFR AND IFR. IFR
CONDITIONS SHOULD DOMINATE AT KPOU AND KPSF WITH MVFR AT KALB AND
KGFL...BUT ALL SITES SHOULD HAVE PERIODS OF MVFR AND IFR.
ONCE THIS AREA OF SHOWERS EXITS AROUND 16Z...CEILINGS AND
VISIBILITIES SHOULD BE MAINLY VFR...THROUGH THE AFTERNOON AND IN TO
THE EVENING AS A WARM FRONT TRACKS THROUGH THE REGION. HOWEVER...
THERE ARE INDICATIONS THAT SOME ORGANIZED THUNDERSTORM ACTIVITY
COULD TRACK THROUGH THE REGION DURING THE LATE AFTERNOON. KEEPING
THE PROB30 INDICATIONS FOR THUNDERSTORMS BECAUSE THERE ARE ABOVE
NORMAL CHANCES FOR THUNDERSTORMS...ALTHOUGH SCATTERED...STILL ABOVE
NORMAL CHANCES. INDICATING MVFR CEILINGS AND VISIBILITIES IN
THUNDERSTORMS FOR NOW...BUT THERE COULD BE IFR FOR BRIEF PERIODS IN
ANY THUNDERSTORMS.
THE ORGANIZED THUNDERSTORM ACTIVITY COULD MOVE OUT DURING THE EARLY
EVENING...SO JUST INDICATING VCSH AFTER 00Z...WITH VFR CONDITIONS AS
THE WARM FRONT SHOULD BE EXITING AND THE WARM SECTOR EXPANDS OVER
THE REGION.
VARIABLE MAINLY SOUTHEAST TO SOUTHWEST WINDS AT LESS THAN 10 KT
THROUGH THE EARLY MORNING...BECOMING SOUTH TO SOUTHWEST AROUND 10 KT
AFTER 16Z...THEN TRENDING MORE SOUTHWEST AT LESS THAN 10 KT BY THIS
EVENING. A STEADY LIGHT WIND THIS EVENING MAY PREVENT ANY FOG FROM
FORMING AFTER ANY THUNDERSTORM ACTIVITY EXITS...BUT TOO EARLY TO
TELL WHEN STORMS WILL EXIT AND HOW MUCH WIND THERE WILL BE ONCE WE
BREAK INTO THE WARM SECTOR.
OUTLOOK...
THU-SUN...VFR/MVFR. CHC PM -TSRA EACH DAY. LATE NIGHT AND/OR
EARLY MORNING MVFR/IFR ASSOC WITH FOG POSSIBLE.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS OVER THE NEXT SEVERAL DAYS. A WETTING
RAINFALL OCCURRED IN MOST AREAS EARLY THIS MORNING AND ADDITIONAL
SHOWERS AND THUNDERSTORMS ARE POSSIBLE TODAY INTO THIS EVENING.
RH VALUES WILL ONLY DROP TO 55 TO 70 PERCENT TODAY. S-SW WINDS AT
5-15 MPH ARE EXPECTED TODAY.
W-SW WINDS WILL BE AROUND 5-10 MPH TONIGHT WITH RH VALUES RECOVERING
TO NEAR 100 PERCENT. AN ISOLATED SHOWER OR THUNDERSTORM IS POSSIBLE
TOMORROW WITH RH VALUES DROPPING 40 TO 55 PERCENT TOMORROW AFTERNOON.
&&
.HYDROLOGY...
NO WIDESPREAD HYDROLOGIC CONCERNS OVER THE NEXT FIVE DAYS ACROSS
THE HSA.
SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS THE REGION TODAY. PWAT
VALUES WILL BE ABOVE NORMAL...WITH VALUES UP TO 1.75 INCHES...SO
ANY SHOWER OR THUNDERSTORM IS CAPABLE OF PRODUCING TORRENTIAL
DOWNPOURS. ALTHOUGH WIDESPREAD RIVER FLOODING IS NOT
EXPECTED...SMALL STREAM...POOR DRAINAGE...OR URBAN FLOODING WILL
BE POSSIBLE DEPENDING ON THE EXACT TRACK OF SHOWERS AND
THUNDERSTORMS...ESPECIALLY IF SEVERAL THUNDERSTORMS TRACK OVER THE
SAME LOCATION. 3 HR FFG FROM THE NERFC IS AROUND 2-3 INCHES.
ISOLATED SHOWERS OR THUNDERSTORMS ARE POSSIBLE ON THURSDAY
AFTERNOON. OTHERWISE...IT WILL BE FAIRLY DRY THROUGH THE END OF
THE WORK WEEK. ADDITIONAL SHOWERS OR THUNDERSTORMS ARE POSSIBLE
OVER THE WEEKEND.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...FRUGIS
LONG TERM...NAS
AVIATION...NAS
FIRE WEATHER...FRUGIS
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
325 PM EDT WED MAY 29 2013
.SYNOPSIS...
HIGH PRESSURE OFF THE EAST COAST WILL CONTINUE TO ESTABLISH ITSELF
OVER THE NEXT FEW DAYS WHILE SLOWLY MOVING OUT TO SEA THROUGH THE
WEEKEND. A LOW PRESSURE SYSTEM WILL TRACK INTO THE GREAT LAKES
REGION AND PUSH A COLD FRONT THROUGH BY EARLY NEXT WEEK. HIGH
PRESSURE WILL FILL BACK IN BEHIND THE DEPARTING FRONT.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
THE GFS INITIALIZATION LOOKED SLIGHTLY BETTER THAN THE WRF-NMMB
OVERALL AND GIVEN HOW THE WRF-NMMB IS NOT VERIFYING WELL WITH ITS
CONVECTIVE FCST THRU 18Z IN OUR CWA. WE WILL LEAN THE GFS`S WAY. THE
HRRR WHICH LOOKED PRETTY GOOD THROUGH THIS MORNING IS NOW VERIFYING
TOO HOT, THE LATEST 12Z SPC WRF IS LOOKING BETTER AND OUR POPS AND
WEATHER THROUGH THIS EARLY EVENING IS CLOSEST TO A WRF-AWWE (WHICH
IS VERIFYING PRETTY GOOD ALSO) AND GFS COMBO.
CONVECTION IS STARTING TO FIRE IN WESTERN NY STATE, OVERALL SLIGHTLY
FARTHER NORTH AND SLOWER THAN WHAT THE OVERNIGHT MODELS WERE
SHOWING. THE 12Z MODELS HAVE ADJUSTED NORTHWARD AND WE LOWERED POPS
FOR THE REST OF THIS AFTERNOON INTO THIS EVENING IN THE SOUTHERN
PART OF OUR CWA. 12Z MODEL FCST BULK SHEAR REMAINS IN NY STATE, SO
GREATEST CHANCE FOR MORE ROBUST STORMS REMAIN ALONG THE FAR NRN PART
OF OUR CWA.
THE GFS DOES SHOW A SHORT WAVE LINGERING FAR NORTH INTO THIS EVENING
AND SOME OF THE MESOSCALE MODELS PROLONG CONVECTIVE CHANCES DEEP
INTO THE EVENING. GIVEN THE TENDENCY TODAY HAS BEEN FOR THEM TO BE
TOO CONVECTIVE, WE COMPROMISED AN ENDING POP TIMING THIS EVENING
BETWEEN THEM AND THE FASTER HRRR AND GFS.
FOG SHOULD NOT BE AS MUCH OF A PROBLEM TONIGHT AS LAST NIGHT, MORE
OF THE PATCHIER VARIETY UNLESS A MORE ORGANIZED CONVECTIVE CLUSTER
GETS DEEPER INTO OUR CWA THAN WE ARE THINKING. MIN TEMPS REMAIN A
BLEND OF CONTINUITY AND LATEST STAT GUIDANCE. THERE SHOULD BE SOME
DEBRIS CLOUDINESS AROUND WHICH ADDS SOME REDUCED CONFIDENCE TO MIN
TEMPERATURE FCSTS.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
THE FIRST WIDESPREAD 90 DEGREE DAY IS EXPECTED TO OCCUR TOMORROW
ACROSS A LARGE PART OF OUR CWA. THE AIR MASS AT OR BELOW 850MB IS
FORECAST TO BE 1-2C WARMER THAN TODAY WHICH SHOULD INCREASE THE
NUMBER OF 90 DEGREE READINGS FROM TODAY. OF EQUAL IMPORTANCE IS THE
FORECAST DEW POINTS WHICH STAT GUIDANCE SUGGESTS COULD BE AS LOW AS
THE UPPER 50S. WE DID NOT GO THAT LOW, BUT THE FORECAST DEW POINTS
LOADED ARE RESULTING IN SIMILAR APPARENT TEMPS (HEAT INDICES) AS THE
AIR TEMPERATURES, SO NO HEAT RELATED PRODUCTS YET. WE WILL CONTINUE
TO MAKE MENTION IN THE HWO. OVERALL FORECAST MAX TEMPS ARE BASED ON
FCST 850MB AND 925MB TEMPS AND WERE A STAT GUIDANCE COMPROMISE AND
PRETTY CLOSE TO OUR ONGOING FORECAST. THE SEA BREEZE SHOULD STRUGGLE
TO GET AWAY FROM THE COAST, SO MAX TEMPS JUST INLAND ARE NOT THAT
LOWER.
AS FAR AS CONVECTIVE POTENTIAL GOES, WHILE MODEL FCST CAPES LOOK
ROBUST, THERE IS ALSO FCST CIN AND THE OVERALL LFC IS PRETTY HIGH.
WITHOUT A TRIGGER AND WITH NVA FCST IT WOULD BE TOUGH TO POP MORE
THAN ISOLATED CONVECTION. NO POPS WERE CONTINUED. THE LEAST
CONFIDENCE WOULD BE THE FAR NORTHWEST PART OF OUR CWA.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
THE BIGGEST ISSUE IN THE LONGTERM CONTINUES TO BE THE POTENTIAL FOR
THE FIRST HEAT WAVE OF THE SEASON ACROSS THE PHILADELPHIA METRO AREA
THROUGH AT LEAST SATURDAY. ANOTHER NOTABLE ISSUE COULD BE THE
POSSIBLE SEVERE WEATHER LATE THIS WEEKEND AS A COLD FRONT PRESSES
DOWN FROM THE NORTHWEST TO HELP BREAK DOWN THE HOT/SOMEWHAT HUMID
AIRMASS.
SURFACE AND MID-LEVEL RIDGING WILL BE PLACE PROVIDING THE REGION
WITH A STRENGTHENING SOUTHWESTERLY FLOW. THE MID-LEVEL RIDGING WILL
BE AT ITS STRONGEST ON FRIDAY AND SUBSEQUENTLY FRIDAY LOOKS TO BE
THE HOTTEST DAY OF POSSIBLE HEAT WAVE WITH SATURDAY SLIGHTLY COOLER
WITH MORE UPPER LEVEL MOISTURE STREAMING IN. THE RELATIVELY GOOD
NEWS IS THAT DEWPOINT TEMPERATURES WILL BE RATHER DRY EVEN THOUGH
THEY ARE ADVECTING IN FROM THE SOUTHWEST...UPPER-50S TO LOW-60S. THE
COOLER DEWPOINTS WOULD ALLOW THE HEAT INDICES TO ACTUALLY FEEL A
DEGREE OR TWO COOLER THAN THE AIR TEMPERATURE. GRANTED THIS MAY BE
THE FIRST SIGNIFICANT HEAT EPISODE OF THE YEAR, BUT STILL DECIDED
NOT TO ISSUE ANY HEAT RELATED HEADLINES AND WILL KEEP MENTION IN THE
HWO.
AS FOR SUNDAY, AMPLE SURFACE HEATING WITH A BIT OF MOISTURE, AHEAD
OF THE NEXT COLD FRONT, WILL PROVIDE FOR VOLATILE CONVECTIVE
CONDITIONS. MODELS ARE SHOWING EITHER A THERMAL TROUGH OR LEE-SIDE
TROUGH NEARING FROM THE WEST LATE IN THE MORNING/EARLY AFTERNOON
TIME PERIOD. THIS SHOULD PROVIDE ENOUGH OF A SURFACE FOCUS FOR
POTENTIAL CONVECTIVE INITIATION. THE BETTER DYNAMICS WILL LIE
FURTHER TO THE NORTH ACROSS NEW YORK STATE UNDER A PASSING UPPER JET
AND STRONGER MID-LEVEL WIND FIELD. EITHER WAY THE POTENTIAL EXISTS
FOR CONVECTION GIVEN THE HOT AIRMASS THAT WILL EVENTUALLY HAVE TO
BREAK DOWN...THIS IS THE REASON THAT SPC HAS PLACED OUR FAR NORTHERN
AREA UNDER A DAY-5 OUTLOOK...THOUGH A LOT CAN CHANGE BETWEEN NOW AND
THEN.
THERE IS STILL SOME UNCERTAINTY IN THE TIMING OF THE APPROACHING
COLD FRONT BY LATE SUNDAY INTO MONDAY TIMEFRAME. THE 00Z/28 ECMWF
ENSEMBLE SHOWS THE FRONT SWEEPING THROUGH BY LATE SUNDAY NIGHT WHILE
THE 12Z/28 GEFS IS NEARLY 12 HOURS SLOWER IN PUSHING THE FRONT
THROUGH. EITHER WAY LIKELY POPS PREVAIL FOR A BETTER PART OF
SUNDAY THROUGH MONDAY TIMEFRAME WITH SCATTERED CONVECTION
POSSIBLE. HIGH PRESSURE NOSING IN BEHIND THE DEPARTING LOW LATER
ON MONDAY INTO TUESDAY PROVIDES A REFRESHING AIRMASS CHANGE WITH
SLIGHTLY BELOW NORMAL TEMPERATURES AND MUCH COOLER DEWPOINTS. THIS HIGH
PRESSURE THEN SETTLES IN ACROSS THE REGION PROVIDING VERY LITTLE
IN THE WAY OF ADVERSE SENSIBLE WEATHER. TEMPERATURES WILL MODERATE
RIGHT AROUND NORMAL FOR EARLY JUNE BY WEDNESDAY.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THE 18Z TAFS KEPT THE MENTION OF THUNDER NORTH OF KPHL AND HAVE SOME
MVFR CONDITIONS FOR THURSDAY MORNING.
INTO EARLY THIS EVENING VFR CONDITIONS FORECAST FROM THE KPHL
METRO AREA AIRPORTS SOUTHWARD. LATEST FORECAST SOUNDINGS
SUGGESTING GUSTINESS SHOULD NOT PREVAIL. THERE MAY BE A 1 OR 2 HR
WINDOW LATE THIS AFTERNOON WHERE ISOLATED THUNDER COULD POP, BUT
COVERAGE AND CONFIDENCE TOO LOW TO INCLUDE IN THESE TERMINALS. AT
KRDG AND KABE, WE INCLUDED THUNDERSTORMS LATE AS THEY SHOULD BE
NEAR THE SOUTHERN EDGE OF AN ORGANIZED CLUSTER OF SHOWERS AND
THUNDERSTORMS. SOME GUSTY NORTHWEST WINDS ARE POSSIBLE, EVEN MORE
SO FOR AIRPORTS FARTHER TO THE NORTH.
WINDS OVERALL SHOULD BE SOUTHWEST AT 10 TO 15 KT, NOT ANTICIPATING
THE SEA BREEZE FRONT MAKING MUCH OF A WESTWARD PROGRESSION FROM
THE IMMEDIATE COAST.
REST OF THE EVENING VFR WITH JUST SOME DEBRIS MID TO HIGH LEVEL
CLOUDINESS AROUND. LIGHTER SOUTHWEST WINDS.
OVERNIGHT, WE CARRIED SOME MVFR CONDITIONS IN EITHER HAZE OR FOG
AT SOME OF THE MORE OUTLYING AIRPORTS. THESE CONDITIONS MAY HAVE
TO BE REVISITED FOR POSSIBLE IFR INCLUSION IF THEY ARE AFFECTED
BY PRECIPITATION. LIGHT SOUTHWEST WINDS.
ON THURSDAY, VFR CONDITIONS WITH NO CIGS EXPECTED 9JUST SOME
ISOLATED TO SCATTERED CUMULUS). WEST TO SOUTHWEST WINDS SHOULD
AVERAGE AROUND 10 KTS. NO SEA BREEZE IS EXPECTED TO AFFECT THE
TERMINALS BY 18Z AND EVEN AFTER MAY BE FIGHTING THE WEST WINDS
ABOVE THE BOUNDARY LAYER TO ARRIVE.
OUTLOOK...
FRIDAY - SATURDAY...VFR WITH SOUTHWESTERLY WINDS. POSSIBLE EARLY
MORNING HAZE MVFR VSBYS EACH MORNING.
SUNDAY - MONDAY...MAINLY VFR. SCATTERED THUNDERSTORMS THROUGH MONDAY
MORNING. WINDS BACKING TOWARDS THE NORTHWEST. LOCALLY IFR TO MVFR IN
ANY THUNDERSTORMS.
&&
.MARINE...
WAVE WATCH GUIDANCE IS VERIFYING TOO HIGH WITH SWELLS AND WE
ADJUSTED FORECAST HEIGHTS DOWN ABOUT 1 FOOT. THE GENERAL WARM
SECTOR SOUTHERLY FLOW WILL CONTINUE INTO THURSDAY. GIVEN THAT ITS
WARM IF NOT HOT AIR OVER COOLER WATER, FORECAST WIND SPEEDS ARE
LIKELY TOWARD THE HIGHER END OF EXPECTATIONS AND BELOW SMALL CRAFT
ADVISORY CONDITIONS NONETHELESS.
OUTLOOK...
CONTINUE SUB-ADVISORY CONDITIONS THROUGH AT LEAST LATE
SATURDAY ACROSS ALL OUR WATERS. WINDS WILL BEGIN TO INCREASE LATE
SATURDAY NIGHT THROUGH MONDAY FROM THE SOUTH-SOUTHWEST AS SURFACE
HIGH PRESSURE SLIDES EAST AND A COLD FRONT NEARS FROM THE
NORTHWEST. SEAS RESPOND UPWARD TO AROUND 5 FEET BY SUNDAY MORNING
AND SCA GUSTS LOOK TO COMMENCE DURING THE DAY SUNDAY. THE COLD
FRONT WILL THEN SWEEP THROUGH BY EARLY MONDAY MORNING AND THE
WINDS BACK TOWARDS THE WEST-NORTHWEST BUT MAY REMAIN GUSTY, AT
LEAST ON THE OUTER WATERS, IN THE STRONG COLD AIR ADVECTION TAKING
PLACE ALOFT.
&&
.RIP CURRENTS...
RIP CURRENT AWARENESS WEEK JUNE 2 THROUGH 8.
PSA`S WILL AIR ON KPHI NWR AND POST DAILY AROUND 545 AM. A SHORT
AWARENESS PRESS CONFERENCE IN SURF CITY - LBI, TUE JUNE 4 2PM FOR
THOSE MEDIA REPRESENTATIVES THAT ARE INTERESTED IN RAISING RIP
CURRENT AWARENESS AND CONDITIONS FAVORING UNGUARDED LIFE THREATENING
DANGER IN THE OCEAN SURF ZONE.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...HEAVENER
NEAR TERM...GIGI
SHORT TERM...GIGI
LONG TERM...HEAVENER
AVIATION...GIGI/HEAVENER
MARINE...GIGI/HEAVENER
RIP CURRENTS...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
103 PM EDT WED MAY 29 2013
.SYNOPSIS...
A WARM FRONT WILL CONTINUE TO LIFT NORTHWARD THROUGH TODAY AS AN
AREA OF HIGH PRESSURE OFF THE EASTERN SEABOARD SPREADS ITS INFLUENCE
INTO THE MID ATLANTIC REGION, BRINGING INCREASING HEAT AND HUMIDITY
TO THE AREA THROUGH THIS WEEKEND. FOR EARLY NEXT WEEK, A LOW
PRESSURE SYSTEM EMERGING FROM AROUND THE GREAT LAKES WILL SEND A
COLD FRONT THROUGH OUR REGION BY MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NEXT ESTF UPDATE CONTINUES TO BE HRRR BASED AS PER ITS BEST
HANDLING OF MESOSCALE MODELING OF ONGOING CONVECTION OR LACK
THEREOF. THIS BUMPS UP THE TIMING OF THE GREATEST THREAT IN OUR
FAR NRN CWA TO 21Z OR 22Z. ELSEWHERE WE MODIFIED THE ABERDEEN
SOUNDING AND THE CONVECTIVE TEMP (HIGH 80S) GETS REACHED LATE IN
THE AFTERNOON, SO AN ISOLATED THUNDERSTORM CAN NOT BE RULED OUT
FROM OCCURRING AND LOW POPS WERE MAINTAINED. MOST OF THE
CONVECTIVE STRENGTH PARAMETERS ARE IN THE MODERATE RANGE.
AS FAR AS SEVERE THREAT GOES, AS PREV FCSTR NOTED THAT FCST BULK
SHEAR VALUES ARE NOT VIGOROUS WITHIN OUR CWA, BUT ARE SUPPORTIVE
OF ORGANIZED CONVECTION JUST NORTH. WE HAVE TO WATCH FOR
INITIATION IN NORTHWEST PA THE NEXT HR OR TWO. SO FAR THE
INITIATION HAS BEEN SLIGHTLY MORE SUBDUED AND FARTHER NORTH THAN
THE LATEST HRRR. IF THERE IS CHANCE OF SEVERE IT IS FROM THAT
ONGOING CONVECTION BUILDING INTO OUR CWA. ETA OF ARRIVAL DOES
COINCIDE WELL FOR THUNDERSTORM STRENGTH. ENHANCED WORDING KEPT UP
NORTH.
NO BIG CHANGES WERE MADE TO ANTICIPATED MAX TEMPERATURES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
OTHER THAN TO MOVE THE CONVECTIVE PROCESS ALONG FASTER BY ABOUT AN
HOUR OR TWO, NO BIG CHANGES HERE.
THE LAST BAND OF WHATEVER HEAVY CONVECTION MOVES ESEWD FROM VCNTY
KRDG-KTTN AT AROUND 00-01Z AND WEAKENS JUST TO THE N OF KPNE AND
KACY AROUND 03Z. OTRW A WARM SUMMERLIKE NIGHT.
50 50 BLENDED 00Z/29 GFS/NAM GUIDANCE.
PATCHY FOG POSSIBLE LATE BUT PROBABLY NOTHING LIKE EARLY THIS
MORNING.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
TO START THE LONG TERM, SURFACE HIGH PRESSURE WILL BE FOUND OVER THE
CENTRAL ATLANTIC, EXTENDING ITS INFLUENCE WESTWARD INTO THE MIDDLE
ATLANTIC STATES. MEANWHILE, STRONG MID-LEVEL RIDGING WILL ALSO BE
TAKING HOLD ACROSS THE REGION. THIS LOOKS TO BE THE BEGINNING OF OUR
FIRST POTENTIAL HEAT WAVE OF THE SEASON, AS A STRENGTHENING
SOUTHWESTERLY FLOW THROUGH THE END OF THE WORK WEEK AND INTO THE
WEEKEND WILL BRING INCREASING HEAT AND HUMIDITY. MODEL 850MB AND
925MB TEMPS SUPPORT MAXIMUM TEMPERATURES EASILY REACHING THE UPPER
80S TO LOWER 90S ACROSS MOST OF THE FORECAST AREA, WITH DEWPOINTS
CLIMBING INTO THE LOWER AND MIDDLE 60S. WE WILL CONTINUE A MENTION
OF THIS EXPECTED HEAT WAVE IN OUR HAZARDOUS WEATHER OUTLOOK, AS HEAT
INDEX VALUES LOOK TO RANGE BETWEEN 90 TO 95 DEGREES.
FOR THE LATTER PART OF THE WEEKEND INTO SUNDAY, THE SURFACE HIGH
PRESSURE AND THE MID-LEVEL RIDGE WILL BOTH BEGIN TO SHIFT EASTWARD,
AS LOW PRESSURE TAKES SHAPE AROUND THE GREAT LAKES WITH A TRAILING
COLD FRONT. WITH THE OVERALL PATTERN BEGINNING TO BREAK DOWN, MODEL
RELATIVE HUMIDITIES INDICATE INCREASING MOISTURE AND CLOUDINESS FOR
SUNDAY, WITH MAXIMUM TEMPERATURES MOSTLY IN THE MIDDLE TO UPPER 80S
ACROSS THE REGION. WE HAVE RETAINED INCREASING POPS FOR
SHWRS/T-STORMS FROM WEST TO EAST ACROSS THE FORECAST AREA DURING
SUNDAY AND SUNDAY NIGHT AS THERE LOOKS TO BE AMPLE INSTABILITY AHEAD
OF THE APPROACHING FRONT. MOST OF THE MODEL GUIDANCE HAS THE COLD
FRONT PASSING THROUGH THE REGION DURING MONDAY, ALTHOUGH THERE ARE
TIMING DIFFERENCES BETWEEN THE GFS, ECMWF, AND OTHERS. AT THIS
EXTENDED TIME RANGE, WE USED A BLEND OF WPC GUIDANCE WITH CONTINUITY
FOR MOST ELEMENTS, INCLUDING TEMPERATURES AND WINDS, AND WE KEPT
HIGH CHANCE POPS IN PLACE ACROSS THE REGION THROUGH MOST OF MONDAY.
WHILE THE FINER DETAILS WILL BE WORKED OUT AS WE GET CLOSER IN TIME
TO THE FRONTAL PASSAGE AND THE MODELS ALIGN MORE WITH REGARDS TO THE
TIMING OF THE FRONT, WHAT IS APPARENT IS THAT TEMPERATURES WILL
RETURN CLOSER TO SEASONAL AVERAGES FOR MONDAY AND TUESDAY.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
WITH THE 18Z TAFS WE ARE KEEPING THE MENTION OF THUNDER NORTH OF
KPHL AND HAVE SOME MVFR CONDITIONS FOR THURSDAY MORNING.
INTO EARLY THIS EVENING VFR CONDITIONS FORECAST FROM THE KPHL
METRO AREA AIRPORTS SOUTHWARD. LATEST FORECAST SOUNDINGS
SUGGESTING GUSTINESS SHOULD NOT PREVAIL. THERE MAY BE A 1 OR 2 HR
WINDOW LATE THIS AFTERNOON WHERE ISOLATED THUNDER COULD POP, BUT
COVERAGE AND CONFIDENCE TOO LOW TO INCLUDE IN THESE TERMINALS. AT
KRDG AND KABE, WE INCLUDED THUNDERSTORMS LATE AS THEY SHOULD BE
NEAR THE SOUTHERN EDGE OF AN ORGANIZED CLUSTER OF SHOWERS AND
THUNDERSTORMS. SOME GUSTY NORTHWEST WINDS ARE POSSIBLE, EVEN MORE
SO FOR AIRPORTS FARTHER TO THE NORTH.
WINDS OVERALL SHOULD BE SOUTHWEST AT 10 TO 15 KT, NOT ANTICIPATING
THE SEA BREEZE FRONT MAKING MUCH OF A WESTWARD PROGRESSION FROM
THE IMMEDIATE COAST.
REST OF THE EVENING VFR WITH JUST SOME DEBRIS MID TO HIGH LEVEL
CLOUDINESS AROUND. LIGHTER SOUTHWEST WINDS.
OVERNIGHT, WE CARRIED SOME MVFR CONDITIONS IN EITHER HAZE OR FOG
AT SOME OF THE MORE OUTLYING AIRPORTS. THESE CONDITIONS MAY HAVE
TO BE REVISITED FOR POSSIBLE IFR INCLUSION IF THEY ARE AFFECTED
BY PRECIPITATION. LIGHT SOUTHWEST WINDS.
ON THURSDAY, VFR CONDITIONS WITH NO CIGS EXPECTED 9JUST SOME
ISOLATED TO SCATTERED CUMULUS). WEST TO SOUTHWEST WINDS SHOULD
AVERAGE AROUND 10 KTS. NO SEA BREEZE IS EXPECTED TO AFFECT THE
TERMINALS BY 18Z AND EVEN AFTER MAY BE FIGHTING THE WEST WINDS
ABOVE THE BOUNDARY LAYER TO ARRIVE.
OUTLOOK...
THURSDAY NIGHT THROUGH SATURDAY...MAINLY VFR CONDITIONS EXPECTED
WITH SOUTHWESTERLY WINDS. SOME LOCAL REDUCED VSBYS POSSIBLE EACH
MORNING IN HAZE.
SUNDAY...MAINLY VFR CONDITIONS THROUGH THE DAY, WITH SUB-VFR
CONDITIONS POSSIBLE IN SHWRS/T-STORMS BY LATE-DAY AND INTO SUNDAY
NIGHT.
&&
.MARINE...
A GENERALLY SSW 10-20 KT FLOW PREVAILS TODAY AND TONIGHT WITH NO
HEADLINE. MAYBE A BIT OF VSBY RESTRICTION IN HAZE EARLY THURSDAY
MORNING. WINDS WILL PROBABLY TURN SSE ALONG THE COASTS FOR A TIME
THIS AFTN BUT EVEN THERE..THE WSW GRADIENT FLOW MAY PREVENT MUCH
OF AN EAST OF SOUTH TURN.
OUTLOOK...
WITH OFFSHORE HIGH PRESSURE INFLUENCING THE MID ATLANTIC REGION AND
OUR WATERS, SUB-SCA CONDITIONS ARE EXPECTED ON OUR WATERS FROM
THURSDAY THROUGH THE FIRST PART OF THE WEEKEND. WINDS THROUGH THIS
TIME FRAME WILL MAINLY BE OUT OF THE SOUTHWEST, WITH SEAS IN THE 3
TO 4 FOOT RANGE FOR OUR COASTAL WATERS AND 1 TO 3 FOOT SEAS IN
DELAWARE BAY. GOING INTO SUNDAY WITH HIGH PRESSURE DRIFTING FARTHER
EAST INTO THE CENTRAL ATLANTIC AND A COLD FRONT APPROACHING THE
REGION FROM THE WEST, WE EXPECT WIND GUSTS AND SEAS TO REACH SMALL
CRAFT ADVISORY LEVELS.
&&
.RIP CURRENTS...
TODAYS RIP CURRENT RISK IS AGAIN LOW BASED ON A 2 FT SWELL 9 SECOND
PERIOD AND RAN IT EITHER WITH A WIND 2115 OR 1812 WITH NEARLY
IDENTICAL LOW RISK RESULTS FOR BOTH NJ AND DE.
RIP CURRENT AWARENESS WEEK JUNE 2 THROUGH 8.
PSA`S WILL AIR ON KPHI NWR AND POST DAILY AROUND 545 AM. A SHORT
AWARENESS PRESS CONFERENCE IN SURF CITY - LBI, TUE JUNE 4 2PM FOR
THOSE MEDIA REPRESENTATIVES THAT ARE INTERESTED IN RAISING RIP
CURRENT AWARENESS AND CONDITIONS FAVORING UNGUARDED LIFE THREATENING
DANGER IN THE OCEAN SURF ZONE.
MORE ON THIS IN THE AFD NEXT MONDAY JUNE 3.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KLINE
NEAR TERM...GIGI
SHORT TERM...DRAG
LONG TERM...KLINE
AVIATION...GIGI/KLINE
MARINE...DRAG/KLINE
RIP CURRENTS...GIGI
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
250 PM EDT WED MAY 29 2013
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
CURRENT SATELLITE LOOP SHOWS BKN TO OVC ACROSS THE AREA WITH THE
CLOUDS ROTATING AROUND THE HIGH PRESSURE RIDGE. THE SURFACE AND UPPER
LEVEL RIDGES ARE ALMOST VERTICALLY STACKED WHICH IS DOING A VERY GOOD
JOB OF KEEPING ANY CU DEVELOPMENT FROM BECOMING A SHOWER/THUNDERSTORM.
EVEN WITH THE GOOD MOIST EASTERLY FLOW THIS RIDGE SHOULD KEEP UP
PRECIPITATION FREE THROUGH THE SHORT TERM. A FEW OF OUR LOCAL
MODELS...THE HRRR AND THE LOCAL WRF...ARE TRYING TO SHOW SOME
SHOWERS DEVELOPING THIS AFTERNOON ACROSS OUR SOUTHEASTERN COUNTIES.
BOTH OF THESE MODELS APPEAR TO BE PICKING UP ON WHAT LOOKS TO BE A
SEA BREEZE FRONT AND BRINGS IN SO LIGHT SHOWERS THIS AFTERNOON. THE
RIDGE IS FIRMLY ENTRENCHED ACROSS SE GA SO I WOULD TEND TO RULE OUT
ANY PRECIP TODAY OR THURSDAY. FOR NOW AM KEEPING ANY PRECIP WORDING
OUT WITH POPS REMAINING BELOW 15 PERCENT. WITH THE MOIST EASTERLY
FLOW WE WILL SEE INCREASED CLOUD COVER AGAIN THURSDAY WITH SOME LOW
STRATUS MOVING IN TONIGHT. THESE LOW CLOUDS WILL KEEP TEMPS UP A
LITTLE HIGHER THAN THE PAST COUPLE OF NIGHTS WITH MAX TEMPS THROUGH
THURSDAY STAY IN THE 80S AND 90S.
01
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
MAINLY ONLY TWEAKS TO THE LONG TERM. CAN NOT COMPLETELY RULE OUT
SMALL CHANCES FOR SHOWERS/STORMS FRIDAY AFTERNOON OVER THE WESTERN CWA
AND SATURDAY AFTERNOON FOR MUCH OF N AND CENTRAL GA. SHOWERS AND
STORMS STILL MOST LIKELY SUNDAY AND MONDAY.
BDL
PREVIOUS DISCUSSION...
ECMWF AND GFS IN GOOD AGREEMENT INTO THE WEEKEND WITH DIFFERENCES
DEVELOPING AT THE EARLY PART OF NEXT WEEK. THE H5 RIDGE MAINTAINS
ITS HOLD OVER THE CWA THROUGH FRIDAY...THEN THE RIDGE BEGINS TO
BREAK DOWN AS THE UPPER TROUGH MOVES INTO THE MIDWEST. THIS WILL
DRIVE A COLD FRONT INTO THE TENNESSEE AND OHIO VALLEYS LATE SATURDAY
AND INTO SUNDAY AND MONDAY. THE ECMWF IS A LITTLE FASTER AND BRINGS
MOISTURE WITH THE FRONT INTO THE CWA LATE SATURDAY NIGHT. BOTH
MODELS PROG THE FRONT TO TAP INTO GULF MOISTURE SUNDAY BRINGING A
GOOD CHANCE OF PRECIP TO MUCH OF THE CWA. DIFFERENCES DEVELOP SUNDAY
NIGHT/MONDAY ON THE SPEED OF EXITING THE FRONT AND ASSOCIATED
MOISTURE. THE ECMWF PUSHES THE FRONT THROUGH BUT THE SOUTHEAST
CORNER OF THE CWA BY 12Z MONDAY WHILE THE GFS HOLDS THE FRONT BACK
CLEARING ONLY THE NORTHWEST PART OF THE CWA BY 12Z MON AND THEN
DEVELOPS A SECONDARY UPPER WAVE THAT INCREASES MOISTURE OVER MOST OF
THE CWA DURING THE DAY MONDAY. AT THIS POINT WILL MAINTAIN HIGH POPS
SUNDAY AND MONDAY AND BRING LOW OR NO POPS ON TUESDAY.
17
&&
.AVIATION...
18Z UPDATE...
WITH GOOD MOIST EASTERLY FLOW ACROSS THE AREA...SEEING MOSTLY
CLOUDY SKIES WITH CEILINGS IN THE SCT-BKN 3000-4000FT LEVEL.
CEILINGS ARE SLOWLY LIFTING AND SHOULD GET UP INTO THE 5000-6000FT
RANGE. WITH THE HIGH PRESSURE RIDGE STILL OVER THE STATE NO
PRECIPITATION OR RESTRICTION TO VSBYS IS EXPECT. WINDS WILL ALSO
STY OUT OF THE E TO SE IN THE 5-10KT RANGE.
//ATL CONFIDENCE...18Z UPDATE...
CONFIDENCE HIGH ON ALL ELEMENTS
01
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 64 87 66 85 / 5 5 5 10
ATLANTA 67 85 66 85 / 5 5 5 10
BLAIRSVILLE 60 83 63 82 / 5 5 5 10
CARTERSVILLE 65 86 66 85 / 5 5 10 20
COLUMBUS 68 88 68 89 / 10 10 10 20
GAINESVILLE 65 83 66 83 / 5 5 5 10
MACON 66 88 66 88 / 5 5 5 10
ROME 65 87 66 85 / 5 10 10 30
PEACHTREE CITY 65 86 66 85 / 5 5 5 10
VIDALIA 68 90 67 90 / 5 5 5 10
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...01
LONG TERM....BDL
AVIATION...01
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
149 PM EDT WED MAY 29 2013
.SHORT TERM /TODAY THROUGH THURSDAY/...
SHORT TERM REMAINS QUIET FOR THE MOST PART...WITH RIDGING ALOFT
AND MOIST SOUTHERLY SURFACE FLOW AROUND THE WESTERN PERIPHERY OF A
HIGH IN THE ATLANTIC. A WEAKNESS IN THE FLOW ALOFT OVER THE
BAHAMAS HAS LED TO AN INCREASE IN CONVECTIVE ACTIVITY...AND SOME
MOISTURE FROM THIS SYSTEM IS PROGGED TO MOVE ACROSS FLORIDA TODAY
AND INTO THE DEEP SOUTH TONIGHT. NAM AND SREF BRING SOME PRECIP TO
SOUTHWEST ZONES...BUT ECMWF AND GFS KEEP THE AREA DRY. NAM GOES
GANGBUSTERS WITH THE CAPE...WITH OVER 1500 J/KG ACROSS SOUTHERN
AND WESTERN ZONES...WHEREAS ALL OTHER GUIDANCE KEEPS CAPE VALUES
BELOW ABOUT 800 J/KG. HPC DOES PAINT SOME LIGHT QPF FROM
APPROXIMATELY CARROLLTON TO CORDELE AND POINTS SOUTH AND
WEST...AND LOCAL WRF AND HRRR BOTH TRY TO DEVELOP SOME POP-UP
CONVECTION THIS AFTERNOON BUT KEEP MOST OF THE CONVECTION IN
ALABAMA. FOR NOW HOWEVER AM KEEPING ANY PRECIP WORDING OUT WITH
POPS REMAINING BELOW 15 PERCENT IN THOSE AREAS BUT TRENDS WILL
HAVE TO BE MONITORED. BIGGER IMPACT WILL BE FROM THE STRATUS THAT
IS EXPECTED TO MOVE IN OVERNIGHT AND EARLY THURSDAY... WHICH WILL
KEEP TEMPS UP A LITTLE HIGHER THAN THE PAST COUPLE OF NIGHTS. MAX
TEMPS THROUGH THE SHORT TERM WILL AGAIN BE ON THE WARM SIDE BUT
ONLY A COUPLE OF DEGREES ABOVE SEASONAL NORMALS.
TDP
LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
ECMWF AND GFS IN GOOD AGREEMENT INTO THE WEEKEND WITH DIFFERENCES
DEVELOPING AT THE EARLY PART OF NEXT WEEK. THE H5 RIDGE MAINTAINS
ITS HOLD OVER THE CWA THROUGH FRIDAY...THEN THE RIDGE BEGINS TO
BREAK DOWN AS THE UPPER TROUGH MOVES INTO THE MIDWEST. THIS WILL
DRIVE A COLD FRONT INTO THE TENNESSEE AND OHIO VALLEYS LATE SATURDAY
AND INTO SUNDAY AND MONDAY. THE ECMWF IS A LITTLE FASTER AND BRINGS
MOISTURE WITH THE FRONT INTO THE CWA LATE SATURDAY NIGHT. BOTH
MODELS PROG THE FRONT TO TAP INTO GULF MOISTURE SUNDAY BRINGING A
GOOD CHANCE OF PRECIP TO MUCH OF THE CWA. DIFFERENCES DEVELOP SUNDAY
NIGHT/MONDAY ON THE SPEED OF EXITING THE FRONT AND ASSOCIATED
MOISTURE. THE ECMWF PUSHES THE FRONT THROUGH BUT THE SOUTHEAST
CORNER OF THE CWA BY 12Z MONDAY WHILE THE GFS HOLDS THE FRONT BACK
CLEARING ONLY THE NORTHWEST PART OF THE CWA BY 12Z MON AND THEN
DEVELOPS A SECONDARY UPPER WAVE THAT INCREASES MOISTURE OVER MOST OF
THE CWA DURING THE DAY MONDAY. AT THIS POINT WILL MAINTAIN HIGH POPS
SUNDAY AND MONDAY AND BRING LOW OR NO POPS ON TUESDAY.
17
&&
.AVIATION...
18Z UPDATE...
WITH GOOD MOIST EASTERLY FLOW ACROSS THE AREA...SEEING MOSTLY
CLOUDY SKIES WITH CEILINGS IN THE SCT-BKN 3000-4000FT LEVEL.
CEILINGS ARE SLOWLY LIFTING AND SHOULD GET UP INTO THE 5000-6000FT
RANGE. WITH THE HIGH PRESSURE RIDGE STILL OVER THE STATE NO
PRECIPITATION OR RESTRICTION TO VSBYS IS EXPECT. WINDS WILL ALSO
STY OUT OF THE E TO SE IN THE 5-10KT RANGE.
//ATL CONFIDENCE...18Z UPDATE...
CONFIDENCE HIGH ON ALL ELEMENTS
01
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 85 64 85 66 / 5 5 5 5
ATLANTA 84 67 83 66 / 5 5 5 5
BLAIRSVILLE 81 60 81 63 / 0 5 5 5
CARTERSVILLE 85 65 84 66 / 5 5 5 5
COLUMBUS 88 69 87 69 / 5 10 10 5
GAINESVILLE 82 65 81 66 / 5 5 5 5
MACON 88 66 87 67 / 5 5 5 0
ROME 87 65 85 66 / 5 5 10 10
PEACHTREE CITY 85 65 84 66 / 5 5 5 5
VIDALIA 88 69 89 69 / 5 5 5 0
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...01
LONG TERM....BDL
AVIATION...01
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1237 PM CDT WED MAY 29 2013
.UPDATE...
ISSUED AT 1230 PM CDT WED MAY 29 2013
CONVECTIVE TEMPERATURE IS BEING ACHIEVED WITH SATELLITE SHOWING CU
DEVELOPING. THE SFC WIND PLOT INDICATES THE 850MB WARM FRONT IS
SLOWLY MOVING NORTH THROUGH THE CWFA. AS MENTIONED EARLIER... THIS
FEATURE MAY PROVIDE A FOCUS FOR INDIVIDUAL CONVECTION TO BECOME
MORE ORGANIZED DURING THE AFTERNOON.
BASED ON THE LATEST RAP TRENDS FROM THE MCS AND LIFT TOOLS...
CONVECTION IS EXPECTED TO BEGIN DEVELOPING ACROSS THE AREA BY MID
AFTERNOON. ..08..
UPDATE ISSUED AT 939 AM CDT WED MAY 29 2013
12Z UA ANALYSIS IS INTERESTING. THERE IS A STRONG PLUME OF DEEP
MOISTURE RUNNING FROM NORTHERN MEXICO INTO NORTHWEST MISSOURI.
KTOP MAY BE PARTIALLY CONTAMINATED BY CONVECTION BUT DEW POINTS IN
THE MID TEENS ARE PRESENT IN THIS PLUME. THE 850MB WARM FRONT RUNS
FROM A LOW IN NORTHWEST KANSAS...TO JUST NORTH OF KOMA...TO NEAR KILX.
THE CURRENT CONVECTION THAT HAS DEVELOPED IN THE TRI-STATE AREA OF
NE/KS/MO WILL MAINTAIN ITSELF THROUGH THE MORNING AS IT IS LOCATED
IN THE BETTER MOISTURE AND STRONGER LLJ.
MCS AND LIFT TOOLS INDICATE THIS CONVECTION SHOULD CONTINUE MOVING
NORTHEASTWARD THROUGH THE LATE MORNING AND AFTERNOON. A THETA E
GRADIENT DOES DEVELOP BY LATE MORNING/EARLY AFTERNOON OVER THE
CWFA MOST LIKELY IN RESPONSE TO THE 850MB WARM FRONT.
CONVECTION OVER THE CWFA WILL BE SEEN BUT WE WILL LIKELY HOLD OFF
UNTIL CONVECTIVE TEMPERATURE IS ACHIEVED. CONVECTIVE TEMPERATURE
SHOULD BE ACHIEVED AROUND MID DAY PLUS/MINUS AN HOUR. WEAK VORT
MAXES MOVING ALONG IN THE FLOW ALOFT IS EXPECTED TO ALLOW
CONVECTION TO BECOME MORE NUMEROUS AS THE AFTERNOON PROGRESSES.
THE 850MB WARM FRONT MAY ALLOW INDIVIDUAL CELLS TO BECOME MORE
ORGANIZED DURING THE AFTERNOON HOURS. ..08..
UPDATE ISSUED AT 650 AM CDT WED MAY 29 2013
THE FLASH FLOOD WATCH WAS DROPPED AROUND 6 AM WITH THE LAST OF THE
OVERNIGHT MCS MOVING EAST OF THE AREA. NO CHANGES WERE MADE TO THE
REST OF THE FORECAST HOWEVER THE ELEVATED TSRA JUST SHOWING UP IN
NORTHEAST KANSAS AND NW MO WILL HAVE TO BE WATCH. CURRENT
TRAJECTORY SHOULD KEEP IT WEST OF THE FORECAST AREA THIS MORNING.
IF IT SPREADS FURTHER EAST THAN EXPECTED THAN POPS WILL HAVE TO BE
ADJUSTED UP FOR IN THE WEST FOR THIS MORNING.
DLF
&&
.SYNOPSIS...
ISSUED AT 357 AM CDT WED MAY 29 2013
A STATIONARY FRONT WAS LOCATED JUST NORTH OF THE FORECAST AREA
EARLY THIS MORNING. THE FRONT EXTENDED SOUTHWEST INTO LOW PRESSURE
OVER EASTERN COLORADO. THE UPPER TROF WAS STILL OVER ROCKIES THIS
MORNING WITH A BROAD AREA OF SOUTHWESTERLY FLOW DOWNSTREAM INTO
THE CENTRAL U.S. THE LATEST MCS TO MOVE THROUGH THE REGION WAS
OVER THE SOUTHERN CWFA AND IS ON TRACK TO EXIT THE FORECAST AREA
AROUND 12Z.
&&
.SHORT TERM...(TODAY)
ISSUED AT 357 AM CDT WED MAY 29 2013
CATEGORICAL POPS WERE CONTINUED OVER THE SOUTH PRIOR TO 12Z...TO
COVER THE EXITING MCS. AFTER THAT HAVE PULLED POPS BACK TO CHANCE
CATEGORY FOR THE REST OF THE DAY. WITH THE STATIONARY FRONT NORTH
OF THE FORECAST AREA THERE WILL BE A LACK OF A SIGNIFICANT FEATURE
FOR CONVECTION TO FOCUS ON THE REST OF THE DAY. MODELS ARE SHOWING
A WEAK S/W LIFTING THROUGH THIS AFTERNOON...DURING PEAK HEATING.
PW/S WILL STILL EXCEED 1.5 INCHES OVER THE AREA TODAY SO ANY
STORMS THAT DEVELOP COULD PRODUCE BRIEF HEAVY RAINS. SINCE THERE
WILL NOT BE ANY SURFACE BOUNDARIES OVER AREA TO HELP ORGANIZE STORMS
THAT DEVELOP...THE THREAT OF WIDESPREAD HEAVY RAINS WILL BE LOW.
THEREFORE THE FLASH FLOOD WATCH WILL NOT BE EXTENDED PAST 12Z
PROVIDED THE CURRENT MCS IS OUT OF THE AREA BY THAT TIME. AFTER
THE MCS MOVES EAST OF THE AREA WE SHOULD SEE SOME FILTERED SUN BY
LATE MORNING OR EARLY AFTERNOON WHICH WILL HELP PUSH TEMPERATURES
INTO THE LOW TO MID 80S OVER MOST OF THE AREA.
.LONG TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 357 AM CDT WED MAY 29 2013
ACTIVE PATTERN WILL KEEP A CONTINUED THREAT OF THUNDERSTORMS...HEAVY
RAIN AND FLOODING THROUGH FRIDAY. UPPER WAVE PROGGED TO SWEEP PAST
TO THE NORTH ON SATURDAY WILL SHUNT THE PERSISTENT STREAM OF GULF
MOISTURE EASTWARD TOWARD THE NORTHEAST U.S...ENDING THE HEAVY RAIN
THREAT. HIGH PRESSURE THAT FOLLOWS FOR SUNDAY INTO AT LEAST MONDAY
WILL PROVIDE A MUCH NEEDED BREAK OF DRY AND SOMEWHAT COOLER WEATHER.
TONIGHT...FORECAST MODELS INDICATE CONDITIONS OVERALL WILL BE LESS
SUPPORTIVE OF ORGANIZED MCS ACTIVITY AFFECTING THE FORECAST AREA.
THE 850 MB CONVERGENCE AXIS AND SURFACE BOUNDARY OVER THE FORECAST
AREA TONIGHT WILL BE PUSHED WELL TO THE NORTH...BUT THERE WILL STILL
BE ADDITIONAL RIPPLES IN THE S-SW UPPER LEVEL FLOW AND POSSIBLE WEAK
LOW LEVEL BOUNDARIES TO WARRANT AT LEAST LOW END CHANCE POPS FOR
THUNDERSTORMS.
THURSDAY AND FRIDAY...THE HEAVY RAINFALL THREAT RETURNS AS MODELS CONTINUE
TO DEPICT A STRONG UPPER LEVEL WAVE...CURRENTLY MOVING THROUGH THE 4
CORNERS REGION...TO LIFT THROUGH DURING PEAK HEATING THURSDAY. THIS
WOULD LIKELY BE FOLLOWED BY ADDITIONAL WAVES AND MCS/S OVERNIGHT
OVER THE REGION AND POSSIBLY INTO THE LOCAL AREA...MUCH LIKE WHAT
HAS OCCURRED THE PAST SEVERAL NIGHTS. THIS WILL ALSO PRESENT A
CONTINUED RISK FOR SEVERE STORMS AND SPC HAS A SLIGHT RISK OVER THE
ENTIRE FORECAST AREA. WITH A SIMILAR MOISTURE FEED AS THE PAST
SEVERAL DAYS...WILL CARRY A WIDESPREAD...BROAD-BRUSHED 1 TO ROUGHLY
1.4 INCHES OF QPF FOR THE DAYTIME THURSDAY. MUCH HIGHER AMOUNTS WILL
BE POSSIBLE AND WILL LIKELY NEED A FLASH FLOOD WATCH BEGINNING
THURSDAY...POSSIBLY CONTINUING THROUGH FRIDAY...WHEN ADDITIONAL
WAVES AHEAD OF THE APPROACHING UPPER WAVE WILL BE POSSIBLE DURING
PEAK HEATING. THIS WILL ALSO PRESENT A CONTINUED RISK FOR SEVERE
STORMS WITH THE ADDED SUPPORT OF A STRONGER FLOW ALOFT AHEAD OF THE
APPROACHING UPPER WAVE. TEMPERATURES THROUGHOUT WILL BE DEPENDENT ON
THE TIMING OF THUNDERSTORM COMPLEXES...AND FOR NOW WILL STAY WITH
HIGHS IN THE 70S TO LOWER 80S AND LOWS IN THE 60S.
RAIN AND THUNDERSTORM CHANCES WILL CONTINUE FRIDAY NIGHT INTO
SATURDAY...BUT THE RISK FOR HEAVY RAIN SHOULD DIMINISH CONSIDERABLY
AS THE FEED OF GULF MOISTURE PUSHES EAST OF THE REGION. TEMPERATURES
MAY BE LIMITED TO HIGHS ONLY IN THE 60S AS CANADIAN HIGH PRESSURE
BUILDS IN UNDER A SHORT PERIOD OF W-NW FLOW ALOFT. EARLY NEXT
WEEK...TEMPERATURES SHOULD MODERATE AT LEAST BACK INTO THE 70S WITH
RAIN CHANCES RETURNING LATE TUESDAY. SHEETS
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1230 PM CDT WED MAY 29 2013
VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH 06Z/30. SATELLITE
SHOWS DIURNAL CUMULUS CLOUDS DEVELOPING WHICH SHOULD EVOLVE INTO
ISOLD TO SCATTERED SHRA/TSRA. IF A TSRA AFFECTS A TAF SITE A BRIEF
PERIOD OF MVFR CONDITION MAY OCCUR. AFT 06Z/30 VFR CONDITIONS
SHOULD CONTINUE BUT ANOTHER NOCTURNAL TSRA COMPLEX WILL DEVELOP IN
WESTERN IOWA THAT SLOWLY MOVES EAST. AFT 12Z/30 THIS TSRA COMPLEX
WILL AFFECT EASTERN IOWA AND EVENTUALLY NORTHERN ILLINOIS AND
POSSIBLY BRING MVFR CONDITIONS. ..08..
&&
.HYDROLOGY...
ISSUED AT 357 AM CDT WED MAY 29 2013
THE THREAT OF HEAVY RAINFALL AND FLASH FLOODING HAS DIMINISHED SOME
FOR TODAY...BUT WILL RETURN THURSDAY AND FRIDAY WHEN ADDITIONAL
LARGE THUNDERSTORM COMPLEXES WITH HEAVY RAINFALL APPEAR LIKELY. A
FLASH FLOOD WATCH MAY BE NEEDED...ESPECIALLY OVER THE FORECAST AREA
SOUTH OF I-80 THAT IS SATURATED FROM NUMEROUS ROUNDS OF HEAVY
RAINFALL OVER THE PAST 3 TO 5 DAYS.
MODERATE TO MAJOR RIVER FLOODING...AND IN SOME INSTANCES RECORD
FLOODING...WILL CONTINUE ALONG TRIBUTARY RIVERS IN EASTERN IA AND
FAR NORTHEAST MISSOURI. THE MISSISSIPPI RIVER IS EXPECTED TO SEE
MODERATE TO MAJOR FLOODING...ESPECIALLY DOWNSTREAM FROM MUSCATINE.
WITH ADDITIONAL RUNOFF FLOWING INTO THE RIVERS FROM LAST NIGHT/S
HEAVY RAIN...AND CHANGES IN FORECAST QPF...CONTINUED ADJUSTMENTS TO
BOTH THE MAGNITUDE AND TIMING OF RIVER FLOODING CAN BE EXPECTED IN
UPDATED WARNING STATEMENTS AND FORECASTS ISSUED LATER TODAY.
SHEETS
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...08
SYNOPSIS...DLF
SHORT TERM...DLF
LONG TERM...SHEETS
AVIATION...08
HYDROLOGY...SHEETS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1147 AM MDT WED MAY 29 2013
.UPDATE...
ISSUED AT 946 AM MDT WED MAY 29 2013
OVERALL THE CURRENT FORECAST THROUGH TONIGHT LOOKS ON
TRACK...FORESEE ONLY REFINING THE TIMING/AREA COVERAGE SOME BASED
ON THE LATEST OBS/MODEL DATA.
CURRENT VISIBLE SATELLITE SHOWS SKIES ARE CLEARING WITH CUMULUS
STARTING TO DEVELOP. UPPER AIR ANALYSIS PLACES A MID LEVEL SHORT
WAVE TROUGH JUST WEST OF THE AREA. AT THE SURFACE A STATIONARY
FRONT WAS OVER THE WESTERN PART OF THE AREA FROM ROUGHLY IMPERIAL
SOUTHWEST TO BETWEEN LIMON AND BURLINGTON. A DRY LINE WAS
SOUTHWEST OF THE AREA BETWEEN LA HUNTA AND LAMAR THEN CURVING
TO THE SOUTHEAST ALONG THE CO/KS BORDER.
AM THINKING THE STORMS SHOULD START TO DEVELOP AROUND 19Z ALONG
THE STATIONARY FRONT AND DRY LINE AND GENERALLY MOVE NORTH-NORTHEAST.
MEANWHILE A 700MB SHORT WAVE TROUGH MOVES IN FROM EASTERN COLORADO
WHICH MAY ALSO FIRE OFF CONVECTION BEHIND THE FRONT. VERY LARGE
HAIL IS POSSIBLE...ESPECIALLY THE FURTHER EAST ONE GOES ACROSS THE
TRI-STATE AREA...WITH THE LIKELIHOOD OF SEVERE HAIL INCREASING
THROUGH THE AFTERNOON AND EVENING. DUE TO MEAN STORM MOTIONS BEING
NEARLY PARALLEL TO THE FRONT THIS AFTERNOON AND EVENING THERE IS
A POSSIBILITY OF HEAVY RAINFALL WITH LOCALIZED FLOODING DUE TO
THUNDERSTORM TRAINING. DAMAGING WINDS WILL BE POSSIBLE WITH ANY
STORM...ESPECIALLY IF THE INDIVIDUAL STORMS MERGE INTO A SQUALL
LINE THIS AFTERNOON. AS MENTIONED EARLIER...THE TORNADO THREAT IS
A POSSIBILITY BUT THE BETTER ENVIRONMENT WILL BE FURTHER SOUTH
WHERE 0-1KM SHEAR WILL BE CLOSER TO 30KTS AND 0-3KM EHI WILL BE
NEAR 4 M2/S2. THE SEVERE WEATHER SHOULD BE OUT OF THE AREA BY OR
SHORTLY AFTER MIDNIGHT AS THE COLD FRONT PUSHES EAST. SOME
THUNDERSTORMS MAY REDEVELOP DURING THE OVERNIGHT HOURS AS AN UPPER
LEVEL SHORT WAVE TROUGH MOVES ACROSS THE AREA...BUT THESE STORMS
SHOULD NOT BECOME SEVERE.
A MULTIMEDIA BRIEFING IS AVAILABLE ON THE WFO GOODLAND HOMEPAGE AT
WEATHER.GOV/GLD CONCERNING THE SEVERE WEATHER THREAT.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY NIGHT)
ISSUED AT 417 AM MDT WED MAY 29 2013
MAIN FORECAST CONCERN IS SIGNIFICANT WEATHER EXPECTED THROUGH
TONIGHT. SATELLITE SHOWING A PROGRESSIVE FLOW FROM THE PACIFIC INTO
NORTH AMERICA. MAIN FEATURE OF INTEREST IS STRONG AND DEVELOPING
UPPER SYSTEM APPROACHING FROM THE WEST. WARM FRONT NORTH OF THE
AREA.
MODELS INITIALIZED FINE AT JET LEVEL BUT WOULD HAVE TO GIVE A SLIGHT
EDGE TO THE GFS AND CANADIAN ON THE JET SEGMENT BEHIND INCOMING
TROUGH. EVEN CLOSE TO THE EVENT MODELS STILL HAVE TROUBLE WITH
INCOMING SHORTWAVE TROUGH. IT HAS BEEN REORGANIZING/DEVELOPING THIS
EVENING AND LOOKS LIKE IT WILL CONTINUE TO DO SO. THROUGH SATELLITE
AND UPPER AIR ANALYSIS...THE CANADIAN IS DOING SLIGHTLY BETTER THAN
THE GFS. EVOLVING SURFACE PATTERN GOING ON RIGHT NOW. RUC IS
CATCHING THINGS WELL. THEN THE CANADIAN AND ECMWF ARE NEXT IN LINE
AND MATCH UP WITH IT. THE CANADIAN...GFS AND ECMWF WERE DOING THE
BEST ON THE LOW LEVEL THERMAL FIELD.
TODAY/TONIGHT...AS HAS BEEN THE CASE THE LAST FEW DAYS THE MODELS
DEVELOP A MID/UPPER JET SEGMENT OVER THE CENTRAL AND EASTERN PORTION
OF THE FORECAST BY 18Z WITH THAT AREA BEING UNDER THE LEFT FRONT
QUADRANT. THE ECMWF HOLDS ONTO THIS OVER THE FORECAST AREA LONGER...
INTO THE EVENING...THAN THE OTHER MODELS. AS THE NIGHT HAS PROGRESSED
THE MODELS HAVE BEEN SLOWING THE ARRIVAL OF THE FRONT. FRONT LOOKS
TO BE NEAR OR JUST EAST OF THE COLORADO BORDER BY 00Z. IN ADDITION
TO THE JET STRONG MID LEVEL LIFT IS AROUND AS WELL. MODELS SHOWING
LITTLE TO NO CAP MY THE MIDDLE OF THE DAY. MAIN QUESTION WILL BE
HOW MUCH MOISTURE WILL THIS ALL HAVE TO WORK WITH. THAT MAY SLOW
DOWN THE ONSET OF THE PRECIPITATION BUT AM THINKING THE LIFT AND
INSTABILITY MAY OVERCOME THIS.
SO HAVE INSERTED POPS BEGINNING AT 15Z AND THEN RAMP THEM QUICKLY
IN THE AFTERNOON. THERE WILL BE A TIGHT GRADIENT OF POPS. IF THERE
IS ANY SLOWING...POPS WILL NEED TO BE PULLED BACK FURTHER WEST. AT
THIS TIME THE EASTERN HALF TO TWO THIRDS THROUGH TONIGHT WILL HAVE
A VERY GOOD CHANCE OF SEEING RAIN/THUNDERSTORMS. PARAMETERS POINT TO
THESE THUNDERSTORMS BECOMING SEVERE AND HAVE INSERTED SEVERE
WORDING FOR THIS AFTERNOON AND TONIGHT. IN ADDITION MODEL QPFS ARE
RATHER HIGH IN THE EASTERN HALF TO TWO THIRDS. NAM/GFS/SREF
PRECIPITABLE WATER VALUES ARE 1 TO 1.25 INCHES. DAY SHIFT MADE A
GOOD POINT WITH THE STORM MOTIONS IN ADVANCE OF THE FRONT
SUPPORTING TRAINING OF THE CELLS. SREF HAS A 30 PERCENT PROBABILITY
OF 1 INCH OF RAINFALL IN THE EAST. SO WENT AHEAD AND ADDED LOCALLY
HEAVY RAINFALL TO THE ABOVE MENTIONED AREA.
THE MOST WIDESPREAD ACTIVITY LOOKS TO END NEAR OR SHORTLY AFTER
06Z. BUT INCOMING JET AND ANOTHER SHORTWAVE TROUGH APPROACH FROM THE
WEST LATE IN THE NIGHT. SO SOME KIND OF CHANCE REMAINS THROUGH THE
NIGHT. NOT SURE ABOUT THE MAXES BUT MESOSCALE MODELS...ESPECIALLY
THE RUC...HAVE MAXES WARMER THAN WHAT I HAVE IN THERE. DID NUDGE
MAXES UP A LITTLE SINCE WARMER MAXES...IF NOT A LOT OF CLOUD COVER...
MAKE SENSE WITH THE SLOWER ARRIVAL OF THE FRONT.
THURSDAY/THURSDAY NIGHT...MODELS TAKE THE LEFT FRONT QUADRANT ACROSS
THE AREA DURING THE AFTERNOON AND EARLY EVENING WITH THE JET SEGMENT
NEAR OR OVER THE NORTHERN PORTION OF THE AREA THROUGH THE REST OF THE
NIGHT. THERE IS ALSO A RATHER STRONG PV ANOMALY WITH THIS. AIR MASS
IS UNSTABLE WITH GOOD LAPSE RATES. SO KEPT A LOW CHANCE OF
THUNDERSTORMS AROUND INTO THE EVENING. LOOK TO HAVE BREEZY OR NEAR
BREEZY WEST TO NORTHWEST WINDS. DEPENDING ON THE AMOUNT OF CLOUD
COVER AND PRECIPITATION...THESE WINDS MAY HELP TEMPERATURES CLIMB A
LITTLE MORE THAN ANTICIPATED. WINDS DIE OFF DURING THE FIRST PART OF
THE NIGHT AND THEN PICK A LITTLE MORE LATER. DEW POINTS WILL BE LOWER.
COULD BE RATHER COOL NIGHT.
FRIDAY/FRIDAY NIGHT...JET STARTS OFF OVER THE NORTHERN PORTION OF
THE AREA AND THEN SOUTH OF THE AREA DURING THE DAY. MODELS WANT TO
GENERATE SOME LIGHT QPF. HOWEVER...THERE IS A RATHER DEEP DRY LAYER
SO KEPT IT DRY AT THIS TIME. IT MAY BE POSSIBLE THAT COULD SEE
SPRINKLES. ONCE AGAIN LOOK TO HAVE BREEZY OR NEAR BREEZY WEST ACROSS
THE AREA. MODELS COOL OFF TEMPERATURES FROM THE PREVIOUS DAY BUT
THOSE WINDS MAY HELP WARM TEMPERATURES A LITTLE MORE. WINDS DIE OFF
MORE THAN THE PREVIOUS NIGHT AND LOOK TO ANOTHER RATHER COOL NIGHT.
.LONG TERM...(SATURDAY THROUGH TUESDAY)
ISSUED AT 417 AM MDT WED MAY 29 2013
EXTENDED RANGE LOOKS TO BE SEASONABLE FOR THE BEGINNING OF JUNE.
PERIOD BEGINS ON SATURDAY WITH THE UPPER LOW THAT WILL BE OVER THE
CENTRAL PLAINS LATE THIS WEEK MOVING EAST INTO THE MIDWEST WHILE A
LONG WAVE RIDGE BUILDS ACROSS THE HIGH PLAINS BEHIND IT ON SUNDAY.
SOUTHERLY FLOW AT 850MB WILL BRING WARMER AIR UP FOR LATE IN THE
WEEKEND THROUGH MID-NEXT WEEK. ON MONDAY A SURFACE TROUGH/DRY LINE
WILL SET UP ALONG OR NEAR THE KANSAS-COLORADO BORDER. AT THE SAME
TIME A NUMBER OF WEAK SHORTWAVE TROUGHS MOVE UP FROM THE SOUTHWEST
TO NORTHEAST ACROSS THE CWA...WHICH ALONG WITH DIURNAL HEATING COULD
SET OFF SOME SHOWERS/STORMS ON MONDAY AND TUESDAY. TUESDAY WILL HAVE
HIGHS WELL ABOVE NORMAL...WITH THE GFS AND GEM PROJECTING 850MB
TEMPS IN EXCESS OF 30C. ECMWF IS A BIT MORE CONSERVATIVE...BUT EVEN
SO BELIEVE HIGHS ON TUESDAY WILL BE WELL INTO THE 90S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1142 AM MDT WED MAY 29 2013
A LOW PRESSURE SYSTEM WILL CONTINUE TO DEEPEN OVER THE REGION
TODAY...ALLOWING FOR UNSTABLE CONDITIONS AND SEVERE THUNDERSTORMS TO
DEVELOP. THUNDERSTORM INITIATION WILL OCCUR AROUND 19Z FOR KGLD AND
WILL APPROACH KMCK AROUND 21Z. THUNDERSTORMS WILL BE PRESENT
NEAR/OVER THE TAF SITES PRODUCING HEAVY RAIN...HAIL AND GUSTY WINDS.
VFR CONDITIONS SHOULD PREVAIL FOR BOTH TAF SITES WITH MVFR CEILINGS
IN THUNDERSTORMS. AS THE FRONT PASSES THROUGH THE REGION...WINDS
WILL SHIFT FROM THE SOUTH TO THE NORTHWEST BY 6Z. THUNDERSTORMS
WILL MOVE OUT OF THE AREA BY 6Z WITH CEILING CONDITIONS RETURNING TO
VFR FOR BOTH TAF SITES.
&&
.FIRE WEATHER...
ISSUED AT 417 AM MDT WED MAY 29 2013
FOR TODAY...MAY BE A BRIEF PERIOD OF LOW RELATIVE HUMIDITIES AND
WINDS. BUT THERE IS A HIGH DEGREE OF UNCERTAINTY OF BOUNDARY
POSITIONS. PLUS DO NOT EXPECT PRECIPITATION TO DEVELOP IN THE
AFTERNOON.
FOR THURSDAY...IF CURRENT FORECAST PANS OUT...MOST OF THE FORECAST
AREA WILL RECEIVE RAINFALL FROM TODAYS SYSTEM. EASTERN COLORADO
WILL GET THE LEAST WITH THE EASTERN HALF TO TWO THIRDS GETTING THE
MOST. THE REASON THIS IS MENTIONED IS BECAUSE WIND SPEEDS AND
RELATIVE HUMIDITIES COULD REACH CRITICAL RED FLAG CRITERIA OVER THE
WESTERN HALF. PLUS ADDITIONAL PRECIPITATION IS EXPECTED ON
THURSDAY. SO AT THIS TIME AM ANTICIPATING NO FIRE WEATHER HIGHLIGHTS
WITH EASTERN COLORADO HAVE THE BEST CHANCE.
FOR FRIDAY...LOWER RELATIVE HUMIDITIES AND GUSTY WEST TO NORTHWEST
WINDS WILL SPREAD OVER MORE OF THE FORECAST AREA THAN THE PREVIOUS
DAY. AGAIN WILL HAVE TO SEE HOW CURRENT PRECIPITATION FORECAST
WORKS OUT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...BULLER
LONG TERM...JJM
AVIATION...MK
FIRE WEATHER...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1014 AM MDT WED MAY 29 2013
.UPDATE...
ISSUED AT 946 AM MDT WED MAY 29 2013
OVERALL THE CURRENT FORECAST THROUGH TONIGHT LOOKS ON
TRACK...FORESEE ONLY REFINING THE TIMING/AREA COVERAGE SOME BASED
ON THE LATEST OBS/MODEL DATA.
CURRENT VISIBLE SATELLITE SHOWS SKIES ARE CLEARING WITH CUMULUS
STARTING TO DEVELOP. UPPER AIR ANALYSIS PLACES A MID LEVEL SHORT
WAVE TROUGH JUST WEST OF THE AREA. AT THE SURFACE A STATIONARY
FRONT WAS OVER THE WESTERN PART OF THE AREA FROM ROUGHLY IMPERIAL
SOUTHWEST TO BETWEEN LIMON AND BURLINGTON. A DRY LINE WAS
SOUTHWEST OF THE AREA BETWEEN LA HUNTA AND LAMAR THEN CURVING
TO THE SOUTHEAST ALONG THE CO/KS BORDER.
AM THINKING THE STORMS SHOULD START TO DEVELOP AROUND 19Z ALONG
THE STATIONARY FRONT AND DRY LINE AND GENERALLY MOVE NORTH-NORTHEAST.
MEANWHILE A 700MB SHORT WAVE TROUGH MOVES IN FROM EASTERN COLORADO
WHICH MAY ALSO FIRE OFF CONVECTION BEHIND THE FRONT. VERY LARGE
HAIL IS POSSIBLE...ESPECIALLY THE FURTHER EAST ONE GOES ACROSS THE
TRI-STATE AREA...WITH THE LIKELIHOOD OF SEVERE HAIL INCREASING
THROUGH THE AFTERNOON AND EVENING. DUE TO MEAN STORM MOTIONS BEING
NEARLY PARALLEL TO THE FRONT THIS AFTERNOON AND EVENING THERE IS
A POSSIBILITY OF HEAVY RAINFALL WITH LOCALIZED FLOODING DUE TO
THUNDERSTORM TRAINING. DAMAGING WINDS WILL BE POSSIBLE WITH ANY
STORM...ESPECIALLY IF THE INDIVIDUAL STORMS MERGE INTO A SQUALL
LINE THIS AFTERNOON. AS MENTIONED EARLIER...THE TORNADO THREAT IS
A POSSIBILITY BUT THE BETTER ENVIRONMENT WILL BE FURTHER SOUTH
WHERE 0-1KM SHEAR WILL BE CLOSER TO 30KTS AND 0-3KM EHI WILL BE
NEAR 4 M2/S2. THE SEVERE WEATHER SHOULD BE OUT OF THE AREA BY OR
SHORTLY AFTER MIDNIGHT AS THE COLD FRONT PUSHES EAST. SOME
THUNDERSTORMS MAY REDEVELOP DURING THE OVERNIGHT HOURS AS AN UPPER
LEVEL SHORT WAVE TROUGH MOVES ACROSS THE AREA...BUT THESE STORMS
SHOULD NOT BECOME SEVERE.
A MULTIMEDIA BRIEFING IS AVAILABLE ON THE WFO GOODLAND HOMEPAGE AT
WEATHER.GOV/GLD CONCERNING THE SEVERE WEATHER THREAT.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY NIGHT)
ISSUED AT 417 AM MDT WED MAY 29 2013
MAIN FORECAST CONCERN IS SIGNIFICANT WEATHER EXPECTED THROUGH
TONIGHT. SATELLITE SHOWING A PROGRESSIVE FLOW FROM THE PACIFIC INTO
NORTH AMERICA. MAIN FEATURE OF INTEREST IS STRONG AND DEVELOPING
UPPER SYSTEM APPROACHING FROM THE WEST. WARM FRONT NORTH OF THE
AREA.
MODELS INITIALIZED FINE AT JET LEVEL BUT WOULD HAVE TO GIVE A SLIGHT
EDGE TO THE GFS AND CANADIAN ON THE JET SEGMENT BEHIND INCOMING
TROUGH. EVEN CLOSE TO THE EVENT MODELS STILL HAVE TROUBLE WITH
INCOMING SHORTWAVE TROUGH. IT HAS BEEN REORGANIZING/DEVELOPING THIS
EVENING AND LOOKS LIKE IT WILL CONTINUE TO DO SO. THROUGH SATELLITE
AND UPPER AIR ANALYSIS...THE CANADIAN IS DOING SLIGHTLY BETTER THAN
THE GFS. EVOLVING SURFACE PATTERN GOING ON RIGHT NOW. RUC IS
CATCHING THINGS WELL. THEN THE CANADIAN AND ECMWF ARE NEXT IN LINE
AND MATCH UP WITH IT. THE CANADIAN...GFS AND ECMWF WERE DOING THE
BEST ON THE LOW LEVEL THERMAL FIELD.
TODAY/TONIGHT...AS HAS BEEN THE CASE THE LAST FEW DAYS THE MODELS
DEVELOP A MID/UPPER JET SEGMENT OVER THE CENTRAL AND EASTERN PORTION
OF THE FORECAST BY 18Z WITH THAT AREA BEING UNDER THE LEFT FRONT
QUADRANT. THE ECMWF HOLDS ONTO THIS OVER THE FORECAST AREA LONGER...
INTO THE EVENING...THAN THE OTHER MODELS. AS THE NIGHT HAS PROGRESSED
THE MODELS HAVE BEEN SLOWING THE ARRIVAL OF THE FRONT. FRONT LOOKS
TO BE NEAR OR JUST EAST OF THE COLORADO BORDER BY 00Z. IN ADDITION
TO THE JET STRONG MID LEVEL LIFT IS AROUND AS WELL. MODELS SHOWING
LITTLE TO NO CAP MY THE MIDDLE OF THE DAY. MAIN QUESTION WILL BE
HOW MUCH MOISTURE WILL THIS ALL HAVE TO WORK WITH. THAT MAY SLOW
DOWN THE ONSET OF THE PRECIPITATION BUT AM THINKING THE LIFT AND
INSTABILITY MAY OVERCOME THIS.
SO HAVE INSERTED POPS BEGINNING AT 15Z AND THEN RAMP THEM QUICKLY
IN THE AFTERNOON. THERE WILL BE A TIGHT GRADIENT OF POPS. IF THERE
IS ANY SLOWING...POPS WILL NEED TO BE PULLED BACK FURTHER WEST. AT
THIS TIME THE EASTERN HALF TO TWO THIRDS THROUGH TONIGHT WILL HAVE
A VERY GOOD CHANCE OF SEEING RAIN/THUNDERSTORMS. PARAMETERS POINT TO
THESE THUNDERSTORMS BECOMING SEVERE AND HAVE INSERTED SEVERE
WORDING FOR THIS AFTERNOON AND TONIGHT. IN ADDITION MODEL QPFS ARE
RATHER HIGH IN THE EASTERN HALF TO TWO THIRDS. NAM/GFS/SREF
PRECIPITABLE WATER VALUES ARE 1 TO 1.25 INCHES. DAY SHIFT MADE A
GOOD POINT WITH THE STORM MOTIONS IN ADVANCE OF THE FRONT
SUPPORTING TRAINING OF THE CELLS. SREF HAS A 30 PERCENT PROBABILITY
OF 1 INCH OF RAINFALL IN THE EAST. SO WENT AHEAD AND ADDED LOCALLY
HEAVY RAINFALL TO THE ABOVE MENTIONED AREA.
THE MOST WIDESPREAD ACTIVITY LOOKS TO END NEAR OR SHORTLY AFTER
06Z. BUT INCOMING JET AND ANOTHER SHORTWAVE TROUGH APPROACH FROM THE
WEST LATE IN THE NIGHT. SO SOME KIND OF CHANCE REMAINS THROUGH THE
NIGHT. NOT SURE ABOUT THE MAXES BUT MESOSCALE MODELS...ESPECIALLY
THE RUC...HAVE MAXES WARMER THAN WHAT I HAVE IN THERE. DID NUDGE
MAXES UP A LITTLE SINCE WARMER MAXES...IF NOT A LOT OF CLOUD COVER...
MAKE SENSE WITH THE SLOWER ARRIVAL OF THE FRONT.
THURSDAY/THURSDAY NIGHT...MODELS TAKE THE LEFT FRONT QUADRANT ACROSS
THE AREA DURING THE AFTERNOON AND EARLY EVENING WITH THE JET SEGMENT
NEAR OR OVER THE NORTHERN PORTION OF THE AREA THROUGH THE REST OF THE
NIGHT. THERE IS ALSO A RATHER STRONG PV ANOMALY WITH THIS. AIR MASS
IS UNSTABLE WITH GOOD LAPSE RATES. SO KEPT A LOW CHANCE OF
THUNDERSTORMS AROUND INTO THE EVENING. LOOK TO HAVE BREEZY OR NEAR
BREEZY WEST TO NORTHWEST WINDS. DEPENDING ON THE AMOUNT OF CLOUD
COVER AND PRECIPITATION...THESE WINDS MAY HELP TEMPERATURES CLIMB A
LITTLE MORE THAN ANTICIPATED. WINDS DIE OFF DURING THE FIRST PART OF
THE NIGHT AND THEN PICK A LITTLE MORE LATER. DEW POINTS WILL BE LOWER.
COULD BE RATHER COOL NIGHT.
FRIDAY/FRIDAY NIGHT...JET STARTS OFF OVER THE NORTHERN PORTION OF
THE AREA AND THEN SOUTH OF THE AREA DURING THE DAY. MODELS WANT TO
GENERATE SOME LIGHT QPF. HOWEVER...THERE IS A RATHER DEEP DRY LAYER
SO KEPT IT DRY AT THIS TIME. IT MAY BE POSSIBLE THAT COULD SEE
SPRINKLES. ONCE AGAIN LOOK TO HAVE BREEZY OR NEAR BREEZY WEST ACROSS
THE AREA. MODELS COOL OFF TEMPERATURES FROM THE PREVIOUS DAY BUT
THOSE WINDS MAY HELP WARM TEMPERATURES A LITTLE MORE. WINDS DIE OFF
MORE THAN THE PREVIOUS NIGHT AND LOOK TO ANOTHER RATHER COOL NIGHT.
.LONG TERM...(SATURDAY THROUGH TUESDAY)
ISSUED AT 417 AM MDT WED MAY 29 2013
EXTENDED RANGE LOOKS TO BE SEASONABLE FOR THE BEGINNING OF JUNE.
PERIOD BEGINS ON SATURDAY WITH THE UPPER LOW THAT WILL BE OVER THE
CENTRAL PLAINS LATE THIS WEEK MOVING EAST INTO THE MIDWEST WHILE A
LONG WAVE RIDGE BUILDS ACROSS THE HIGH PLAINS BEHIND IT ON SUNDAY.
SOUTHERLY FLOW AT 850MB WILL BRING WARMER AIR UP FOR LATE IN THE
WEEKEND THROUGH MID-NEXT WEEK. ON MONDAY A SURFACE TROUGH/DRY LINE
WILL SET UP ALONG OR NEAR THE KANSAS-COLORADO BORDER. AT THE SAME
TIME A NUMBER OF WEAK SHORTWAVE TROUGHS MOVE UP FROM THE SOUTHWEST
TO NORTHEAST ACROSS THE CWA...WHICH ALONG WITH DIURNAL HEATING COULD
SET OFF SOME SHOWERS/STORMS ON MONDAY AND TUESDAY. TUESDAY WILL HAVE
HIGHS WELL ABOVE NORMAL...WITH THE GFS AND GEM PROJECTING 850MB
TEMPS IN EXCESS OF 30C. ECMWF IS A BIT MORE CONSERVATIVE...BUT EVEN
SO BELIEVE HIGHS ON TUESDAY WILL BE WELL INTO THE 90S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 548 AM MDT WED MAY 29 2013
SIGNIFICANT SEVERE WEATHER EVENT TO DEVELOP ACROSS THE AREA THIS
AFTERNOON INTO THIS EVENING. IN GENERAL KMCK WILL HAVE THE GREATEST
THREAT OF HAVING MVFR OR LOWER CONDITIONS. UNTIL THEN GUSTY
SOUTHERLY WINDS WILL OCCUR AT BOTH SITES. FOR KGLD THUNDERSTORM
INITIATION WILL BE VERY NEAR TO THIS SITE. SO AT THIS TIME JUST
CHOSE TO PUT VCTS IN THE TAF. FOR KMCK...FELT MORE COMFORTABLE IN
PUTTING IN SUB VFR CONDITIONS LATER THIS AFTERNOON. HOWEVER...SOME
MODEL OUTPUT BRINGS IN THUNDERSTORMS SOONER THAN THAT. LATER
FORECASTS WILL HAVE TO FINE TUNE THIS. EVEN THOUGH NO VISIBILITY
RESTRICTIONS WERE PUT INTO THE KMCK TAF...VERY HEAVY RAINFALL
COULD DRAMATICALLY LOWER THE VISIBILITY. THAT WILL ALSO NEED TO BE
FINE TUNED AS WELL.
&&
.FIRE WEATHER...
ISSUED AT 417 AM MDT WED MAY 29 2013
FOR TODAY...MAY BE A BRIEF PERIOD OF LOW RELATIVE HUMIDITIES AND
WINDS. BUT THERE IS A HIGH DEGREE OF UNCERTAINTY OF BOUNDARY
POSITIONS. PLUS DO NOT EXPECT PRECIPITATION TO DEVELOP IN THE
AFTERNOON.
FOR THURSDAY...IF CURRENT FORECAST PANS OUT...MOST OF THE FORECAST
AREA WILL RECEIVE RAINFALL FROM TODAYS SYSTEM. EASTERN COLORADO
WILL GET THE LEAST WITH THE EASTERN HALF TO TWO THIRDS GETTING THE
MOST. THE REASON THIS IS MENTIONED IS BECAUSE WIND SPEEDS AND
RELATIVE HUMIDITIES COULD REACH CRITICAL RED FLAG CRITERIA OVER THE
WESTERN HALF. PLUS ADDITIONAL PRECIPITATION IS EXPECTED ON
THURSDAY. SO AT THIS TIME AM ANTICIPATING NO FIRE WEATHER HIGHLIGHTS
WITH EASTERN COLORADO HAVE THE BEST CHANCE.
FOR FRIDAY...LOWER RELATIVE HUMIDITIES AND GUSTY WEST TO NORTHWEST
WINDS WILL SPREAD OVER MORE OF THE FORECAST AREA THAN THE PREVIOUS
DAY. AGAIN WILL HAVE TO SEE HOW CURRENT PRECIPITATION FORECAST
WORKS OUT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...BULLER
LONG TERM...JJM
AVIATION...BULLER
FIRE WEATHER...BULLER
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
356 PM EDT WED MAY 29 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 354 PM EDT WED MAY 29 2013
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW RDG AXIS MOVING
INTO THE UPR GRT LKS DOWNSTREAM OF DEEPENING UPR TROF OVER THE
ROCKIES. ALTHOUGH SOME LO CLDS LINGER WITH LLVL MSTR SHOWN ON LOCAL
12Z RAOBS...COMBINATION OF SUBSIDENCE/LLVL ACYC FLOW ASSOCIATED WITH
RDG AXIS AND ARRIVAL OF VERY DRY AIR ABV THE SHALLOW MSTR AS SHOWN
ON THE 12Z MPX RAOB IS BRINGING DRY WX TO UPR MI. AT MID AFTN...THE
LO CLDS ARE FINALLY MIXING OUT FAIRLY STEADILY. FARTHER TO THE
SW...A PAIR OF SHRTWVS LIFTING NEWD OUT OF THE ROCKIES TROF ARE
BRINGING SOME SHRA/TS TO COME AREAS IN THE PLAINS...ESPECIALLY OVER
IOWA INTO SE MN AHEAD OF SFC-85 WARM FNT.
MAIN FCST CONCERNS TNGT INTO THU WL BE SHRA/TS CHCS ASSOCIATED WITH
RETURNING H85 WARM FNT AND SHRTWVS LIFTING NEWD OUT OF THE ROCKIES
TROF.
TNGT...MODELS ARE IN VERY GOOD AGREEMENT SHOWING CORE OF MID LVL DRY
AIR OVER THE CWA EARLY THIS EVNG UNDER UPR RDG AXIS SHIFTING TO THE
NE WITH APRCH OF WARM FNT TO THE SW. ALTHOUGH THE EARLY EVNG WL
LIKELY BE DRY...EXPECT INCRSG SHRA/TS CHCS BY 03Z WITH APRCH OF
SHRTWV NOW CAUSING SHRA/TS IN IOWA AS WELL AS AXIS OF HIER H85
DEWPTS AT NOSE OF STRENGTHENING H85 LLJ PUSHING KINX AT IWD TO 36 BY
06Z PER GFS FCST SDNGS. SINCE THE SHRTWV/MOISTENING ARE FCST TO
IMPACT MAINLY THE W HALF OF THE CWA...EXPECT THE HIER POPS IN THAT
AREA. IN FACT...THE ERN ZNS MAY REMAIN COMPLETELY DRY WITH KINX FCST
NO HIER THAN ABOUT 25 AT ERY THRU 12Z THU. FCST SDNGS INDICATE
STABILITY WL BE TOO MARGINAL FOR SVR STORMS...WITH SSI NO LOWER THAN
ABOUT -1C AND MUCAPE NO HIER THAN 300-350 J/KG WITH NARROW SKINNY
CAPE. EXPECT THE LOWEST MIN TEMPS OVER THE E CLOSER TO DEPARTING DRY
AIRMASS. AREAS OF FOG ARE LIKELY TO FORM IN THIS AREA UNDER THE MORE
PERSISTENT MID LVL DRY AIR.
THU...AS WARM FNT SHIFTS TO THE N ON THU...EXPECT BULK OF LINGERING
MRNG SHRA/TS OVER MAINLY THE W TO DIMINISH/END. QUESTION THEN
BECOMES WHETHER ADDITIONAL CONVECTION WL FIRE IN THE WARM SECTOR AFT
MRNG LO CLDS DSPT WITH DAYTIME HEATING/MIXING. THE BEST CHC FOR AFTN
SHRA/TS WL BE PROBABLY BE OVER THE W...UNDER LOWER HGTS CLOSER TO
CLOSED LO FCST TO DRIFT NWD THRU THE PLAINS. BUT EVEN THERE...GFS
FCST SDNGS HINT AT SUBSIDENCE INVRN IN THE H75-8 LYR THAT MIGHT
INHIBIT CONVECTION FOR AWHILE. IN FACT...BULK OF NUMERICAL GUIDANCE
SHOWS NO SHRA/TS DVLPG UNTIL 21Z...WHEN SFC TEMPS ARE LIKELY TO RISE
WELL INTO THE 80S UNDER H85 TEMPS IN THE 16-17C RANGE. MODIFIED GFS
FCST SDNG AT IWD FOR T/TD 85/60 YIELDS SBCAPE NEAR 1250 J/KG.
UNIDIRECTIONAL SSW FLOW AND SFC-6KM BULK SHEAR IN THE 20-30KT RANGE
AS WELL AS HI FRZG LVL/WBLB ZERO OF 13.7K FT/12.6K FT WOULD INDICATE
SVR THREAT IS FAIRLY SMALL. SINCE WARM FNT WL PROBABLY STALL OVER NW
LK SUP...PAINTED THE HIER POPS OVER THE KEWEENAW CLOSER TO THIS
BNDRY. SFC-6KM SHEAR IS FCST A BIT HIER IN THIS AREA AND UP TO 40
KTS...BUT LO CLDS SHOULD BE MORE PERSISTENT/STABILITY LOWER OVER THE
KEWEENAW.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 354 PM EDT WED MAY 29 2013
WARMER THAN NORMAL TEMPERATURES AND ACTIVE WEATHER EXPECTED THROUGH
THE END OF THE WORK WEEK AHEAD OF A LOW PRESSURE SYSTEM SHIFTING
EASTWARD FROM THE PLAINS. A COOLING TREND IS EXPECTED OVER THE
WEEKEND WITH NEAR NORMAL TEMPERATURES EXPECTED EARLY NEXT
WEEK...HOWEVER OVERNIGHT LOWS ARE EXPECTED TO BE QUITE COOL EARLY
NEXT WEEK WITH INLAND AREAS LIKELY REACHING THE LOW TO MID 30S.
THURSDAY NIGHT THROUGH SATURDAY...UPPER LEVEL 500MB CLOSED LOW AND
ASSOCIATED SURFACE LOW PRESSURE SYSTEM CENTERED OVER THE DAKOTAS
THURSDAY NIGHT WILL DRIFT SLOWLY EASTWARD INTO WESTERN MN BY
THURSDAY NIGHT. THIS WILL KEEP UPPER MI IN WARM MOIST SOUTHERLY
FLOW. THE BETTER MOISTURE TRANSPORT INTO THE REGION IS PROGGED TO
OCCUR THURSDAY NIGHT THROUGH EARLY FRIDAY MORNING...AS PRESSURE
GRADIENT IS INCREASED BETWEEN THE TROUGH TO THE WEST AND RIDGE TO
THE EAST. UPPER MI IS ON THE NORTHERN FRINGES OF THIS PRESSURE
GRADIENT...DIFFLUENT REGION...ALLOWING WIND SPEEDS TO DECREASE OVER
UPPER MI. AS A RESULT...850MB CONVERGENCE IS ENHANCED OVER NORTHERN
WI AND UPPER MI PROVIDING ENOUGH FORCING TO INCREASE THE CHANCE OF
SHOWERS AND THUNDERSTORMS ACROSS THE REGION. MUCAPE VALUES ARE
PROGGED TO BE AROUND 500-600 J/KG WHICH MAY BE ENHANCED A BIT AS
500MB SHORTWAVE ROTATES THROUGH THE REGION THURSDAY NIGHT. THE
SURFACE LOW AND UPPER LEVEL LOW WILL THEN SHIFT FROM WESTERN MN
FRIDAY MORNING INTO WI AND UPPER MI BY SATURDAY AFTERNOON. DURING
THIS TIME PERIOD THE BETTER CHANCES FOR PRECIPITATION WILL SHIFT
EASTWARD...REMAINING OVER MAINLY EASTERN UPPER MI AND MOST OF LOWER
MI AS THE PRESSURE GRADIENT AND AFOREMENTIONED CONVERGENCE ALSO
SHIFTS EASTWARD. ENOUGH MOISTURE WILL REMAIN IN PLACE OVER MUCH OF
UPPER MI ALONG WITH COOLER AIR MOVING IN THROUGH THE DAY
SATURDAY...TO KEEP THE CHANCE OF SHOWERS AND THUNDERSTORMS IN THE
FORECAST.
SATURDAY NIGHT THROUGH SUNDAY...THE LOW PRESSURE SYSTEM OVER UPPER
MI SATURDAY NIGHT IS EXPECTED TO CONTINUE TO TREK EASTWARD SHIFTING
TO SOUTHERN ONTARIO AND SOUTHERN QUEBEC THROUGH SUNDAY AFTERNOON. AS
THIS HAPPENS...UPPER MI WILL BE PLACED ON THE BACK SIDE OF THE LOW
PRESSURE SYSTEM ALLOWING COOLER AIR TO PUSH INTO THE AREA. ENOUGH
WRAP AROUND MOISTURE WILL LINGER THROUGH SUNDAY AFTERNOON AND
EVENING TO KEEP INCREASED CLOUD COVER OVER THE REGION ALONG WITH THE
CHANCE OF SHOWERS. WHEN PLOTTING 1000-500MB OMEGA ON PLAN VIEW AND
CROSS SECTIONS...INCREASED RH VALUES AND FORCING ARE COLLOCATED OVER
MUCH OF THE UPPER PENINSULA THROUGH SUNDAY AFTERNOON. AS WAS THE
CASE OVER THE LAST FEW SHIFTS...THE GFS TRIES TO PULL DRY AIR INTO
THE REGION MUCH FASTER THAN THE EC/GEM...THEREFORE...WILL KEEP
INCREASED CLOUD COVER IN THE FORECAST INTO THE LATE AFTERNOON INTO
EARLY SUNDAY EVENING. THE GFS WOULD HAVE ALL CLOUD COVER OUT OF THE
AREA BETWEEN 12 AND 18Z SUNDAY.
SUNDAY NIGHT THROUGH WEDNESDAY...IN THE WAKE OF THE UPPER LEVEL
500MB LOW AND SURFACE LOW...EXPECT AN UPPER LEVEL 500MB RIDGE AND
SURFACE HIGH TO BUILD EASTWARD FROM THE PLAINS SUNDAY NIGHT REACHING
THE UPPER GREAT LAKES REGION BY LATE MONDAY MORNING. THE RIDGE WILL
REMAIN IN PLACE THROUGH TUESDAY EVENING...KEEPING CONDITIONS DRY AND
SKIES MOSTLY SUNNY. SUNDAY NIGHT INTO MONDAY NIGHT...OVERNIGHT LOWS
AREA EXPECTED TO BE FAIRLY COLD FOR THIS TIME OF YEAR AS 850MB TEMPS
AREA EXPECTED TO DROP TO AROUND 0C TO 2C. THIS COUPLED WITH CALM
WINDS...CLEAR SKIES AND DRY AIR...WILL ALLOW FOR MAXIMUM RADIATIONAL
COOLING. AREAS INLAND WEST COULD FALL TO NEAR FREEZING SUNDAY NIGHT
WHILE THE INLAND EAST AREAS COULD SEE NEAR FREEZING TEMPERATURES
MONDAY NIGHT AS THE HIGH PRESSURE CENTER SHIFTS EASTWARD. THE NEXT
AREA OF LOW PRESSURE DEVELOPING OVER SOUTHERN CANADA AND THE
NORTHERN ROCKIES MONDAY AFTERNOON WILL SHIFT SLOWLY EASTWARD
REACHING WESTERN UPPER MI BY LATE TUESDAY NIGHT INTO WEDNESDAY
MORNING. SIGNIFICANT TIMING AND SYSTEM INTENSITY DIFFERENCES EXIST
FROM MODEL TO MODEL AND FROM MODEL RUN TO MODEL RUN CAUSING A BELOW
AVERAGE CONFIDENCE LEVEL IN THE FORECAST FOR WEDNESDAY...THEREFORE
HAVE DECIDED TO LEAN TOWARD A CONSENSUS OF THE MODELS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 125 PM EDT WED MAY 29 2013
EXPECT LINGERING SC/MVFR CIGS AT CMX/SAW TO BREAK AND GIVE WAY TO
VFR CONDITIONS IN THE NEXT FEW HRS WITH LARGER SCALE SUBSIDENCE/
DRYING IN THE PRESENCE OF DAYTIME HEATING/MIXING. A DISTURBANCE
MOVING IN FM THE SW WL BRING THE THREAT OF SOME SHRA AND POSSIBLY A
TS TO MAINLY IWD AND CMX TNGT. WITH NOCTURNAL COOLING AND RETURNING
MSTR...EXPECT CONDITIONS TO DETERIORATE TO IFR/MVFR. ALTHOUGH
DAYTIME HEATING/MIXING WL BRING ABOUT IMPROVEMENT ON THU...THE LO
CLDS/MVFR CIGS MAY BE MORE PERSISTENT AT CMX WITH AN UPSLOPE SE WIND
COMPONENT CLOSER TO WARM FNT JUST N OF UPR MI.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 354 PM EDT WED MAY 29 2013
WITH GENERALLY WEAK PRES GRADIENT AND STABLE CONDITIONS OVER LAKE
SUPERIOR...EXPECT WINDS TO BE UNDER 25KT THRU THE WEEK. WIDESPREAD
FOG IS LIKELY...ESPECIALLY AFTER RAINFALL OCCURS OVER THE LAKE. AT
LEAST PATCHY DENSE FOG IS LIKELY INTO SAT. HIGH PRESSURE WILL MOVE
INTO THE AREA SUNDAY NIGHT AND REMAIN OVERHEAD THROUGH LATE TUESDAY
NIGHT...KEEPING WINDS VARIABLE AND LESS THAN 25 KNOTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KEC
AVIATION...KC
MARINE...KEC
AREA FORECAST DISCUSSION
NWS HASTINGS NE
254 PM CDT WED MAY 29 2013
.UPDATE...
ISSUED AT 808 AM CDT WED MAY 29 2013
GIVEN INCREASE IN SHOWERS/FAIRLY WEAK THUNDERSTORMS ACROSS MUCH OF
THE SOUTHEAST 1/4 OF THE CWA ALREADY THIS MORNING...HAVE UPPED
POPS TO 50 PERCENT THIS MORNING ACROSS MUCH OF THE EASTERN 1/2 OF
THE CWA...WHILE KEEPING LOWER POPS IN THE WEST. AM NOT
ANTICIPATING SEVERE STORMS THIS MORNING...BUT SOME SMALL HAIL IS
NOT OUT OF THE QUESTION. ITS A COMPLEX CONVECTIVE SCENARIO
TODAY..WITH THE PRESENCE OF SEVERAL SUBTLE DISTURBANCES IN THE MID
LEVEL FLOW OUT AHEAD OF THE PRIMARY SHORTWAVE TROUGH APPROACHING
FROM THE ROCKIES...VERY POSSIBLY ENSURING THAT AT LEAST SOME
PORTION OF THE CWA WILL SEE RAIN AT ANY GIVEN TIME TODAY.
ON ANOTHER NOTE...REGARDING THE THURSDAY/FRIDAY FIRE WEATHER
CONCERNS FOR OUR WESTERN CWA OUTLINED IN THE PREVIOUS
DISCUSSION...UPON FURTHER INSPECTION THE OFFICIAL FIRE WEATHER
FUEL STATUS FOR ALL NEBRASKA ZONES WAS SET TO UNFAVORABLE FOR
LARGE FIRE GROWTH AS OF YESTERDAY. THIS BASICALLY MEANS THAT
VEGETATION IS GREEN ENOUGH/WET ENOUGH TO PRECLUDE MAJOR FIRE
WEATHER PROBLEMS...ALTHOUGH OF COURSE CAUTION SHOULD STILL BE
USED WHEN BURNING. AS A RESULT OF THIS UNFAVORABLE FUEL
STATUS...WILL BE REMOVING ELEVATED FIRE DANGER MENTION FROM THE
HAZARDOUS WEATHER OUTLOOK.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 406 AM CDT WED MAY 29 2013
MAIN FORECAST CONCERN WILL BE
CHANCES FOR THUNDERSTORMS.
RADAR FROM KLNX SHOWS THAT MANY OF THE THUNDERSTORMS TO THE WEST
HAVE DIMINISHED BUT A RAIN SHIELD REMAINS. THERE ARE A COUPLE OF
BOUNDARIES THAT ARE SHOWING UP ON KUEX RADAR...ONE FROM THE
CONVECTION TO THE WEST AND ANOTHER FROM CONVECTION TO THE SOUTH.
WHEN THESE COLLIDE APPEARS TO BE THE BEST CHANCE FOR SOME SHOWERS
AND THUNDERSTORMS EARLY THIS MORNING. THERE HAVE BEEN A FEW THAT
GOT STARTED BUT SOON WANED.
MODELS ARE SIMILAR WITH THE UPPER LEVEL LOW THAT MOVES FROM THE
NORTHERN ROCKIES INTO THE NORTHERN HIGH PLAINS TODAY AND TONIGHT.
THERE IS A SURFACE LOW ON THE HIGH PLAINS THAT TRIES TO MOVE
EAST...BUT DOES NOT MAKE IT THROUGH THE AREA. THE SURFACE PRESSURE
GRADIENT TIGHTENS THIS MORNING AHEAD OF THE SURFACE LOW. WINDS
WILL START TO INCREASE. THE STRONGEST WINDS WILL BE IN THE
SOUTHERN PART OF THE FORECAST AREA...BUT BREEZY CONDITIONS ARE
EXPECTED ACROSS THE AREA TODAY. WILL KEEP THE WIND ADVISORY AS IS
FOR NOW.
THE NEXT CONCERN WILL BE WHEN THUNDERSTORMS WILL DEVELOP. THE
UPPER LEVEL WAVE WILL START TO AFFECT THE AREA THIS MORNING AND
SOME THUNDERSTORM DEVELOPMENT IS NOT OUT OF THE QUESTION. THE NAM
AND THE GFS SHOW A DEFINITIVE INCREASE IN QPF DURING THE MORNING
BUT THE RAP AND 4KM WRF BOTH HOLD OFF UNTIL LATER. WILL KEEP SOME
LOW POPS IN FOR THE MORNING...BUT RAMP IT UP LATER THIS MORNING
AND EARLY THIS AFTERNOON WHEN THE UPPER WAVE IS MOVING INTO THE
AREA. SEVERE WEATHER IS EXPECTED DURING THE AFTERNOON AND EVENING
WHEN MUCAPES ARE EXPECTED TO BE OVER 3500 J/KG. THE SEVERE WEATHER
WILL LIKELY CONTINUE INTO THE EVENING BUT THE SEVERE THREAT WILL
DIMINISH LATER TONIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 406 AM CDT WED MAY 29 2013
MAIN STORY: A REPRIEVE FROM THE THREAT OF TSTMS WILL OCCUR AS
TEMPS TUMBLE TO BELOW NORMAL THIS WEEKEND...THEN THE THREAT
RETURNS EARLY NEXT WEEK AS SUMMER WARMTH RETURNS.
ALOFT: THE TROF CURRENTLY MOVING THRU THE W WILL CLOSE OFF OVER
THE NRN PLAINS THU NGT-FRI BEFORE OPENING UP AND SLOWLY MIGRATING
INTO THE GREAT LAKES AND MIDWEST THIS WEEKEND. A MODEST SHRTWV
RIDGE WILL ADVANCE INTO THE PLAINS SUN-MON...AS THE NEXT TROF
MOVES INTO THE PAC NW. ALL THE WHILE THE WESTERLIES WILL GRADUALLY
LIFT BACK INTO THE NRN USA.
SFC: A COOL FRONT WILL MOVE THRU LATE THU AFTN/EVE. HOWEVER...THE
TAIL END OF THE FRONT MAY NOT ENTIRELY CLEAR THE SE FRINGE OF OUR
FCST AREA UNTIL FRI EVNG. THIS FRONT WILL BE FOLLOWED BY A SECONDARY
STRONGER COLD FRONT FRI EVNG. HIGH PRES DRIFTS THRU SUN WITH RETURN
FLOW INTENSIFYING WITH ITS DEPARTURE TO THE E AND REDEVELOPMENT OF
THE LEE TROF...AS LOW PRES HEADS E ALONG THE USA-CAN BORDER. HEAT
BUILDS OVER THE REGION MON-TUE UNTIL THE NEXT COOL FRONT MOVES THRU
TUE NGT OR WED. COOL HIGH PRES THEN BUILDS IN THU.
HAZARDS: FIRE WX MAY BECOME A CONCERN THU/FRI BETWEEN 2PM-8PM.
ATTM DO NOT ENVISION A RFW BUT FIRE DANGER COULD BE ELEVATED.
THERE ARE MULTIPLE CHANCES FOR TSTMS THU-FRI BUT COVERAGE AND
INTENSITY WILL BE LOW DUE TO DIMINISHING MSTR/INSTABILITY. SOME
SVR TSTMS WILL BE POSSIBLE EARLY NEXT WEEK AS INSTABILITY
INCREASES.
THE DAILY DETAILS...
THU: THE BACKSIDE OF AN MCS MAY STILL LINGER SE OF THE TRI-CITIES
IN THE MRNG. OTHERWISE DECREASING CLOUDS.
THE DRYLINE WILL PRESS INTO THE FCST AREA IN THE WARM SECTOR OF A
992 MB SFC LOW OVER THE DAKOTAS...WITH ITS ASSOCIATED COOL FRONT
DROPPING INTO THE NW FRINGE LATE. THE LFQ OF THE 80 KT ULJ WILL BE
OVER THE CNTRL PLAINS...BUT HIGH QUALITY MSTR WILL BE RAPIDLY ON THE
DECREASE. AN ISOLATED SHWR/TSTM IS POSSIBLE...MAINLY E OF HWY 281.
FIRE DANGER: WE NEED TO WATCH ALONG AND W OF HWY 183. USED LOWER
NAM 2M DWPTS WHICH DROPS INTO THE UPR 30S. WINDS LOOK MARGINAL.
FRI: WEAK HIGH PRES BUILDS IN BEFORE SECONDARY COLD FRONTAL
PASSAGE. A BREEZY DAY W OF HWY 281. THERE IS A VERY LOW
PROBABILITY FOR AN ISOLATED SHWR/TSTM IN VICINITY OF THE
APPROACHING FRONT AND THE STALLED FRONT OVER THE SE. FIRE DANGER
COULD BE ELEVATED AGAIN W OF HWY 183.
SAT: BREEZY AND COOL WITH HIGH TEMPS ABOUT 10F COOLER THAN
NORMAL. COULD SEE A FEW SPRINKLES N OF I-80 IN THE AFTN.
SUN: NICE AND COMFORTABLE. A GOOD DAY TO OPEN UP THE HOUSE.
SUN NGT: A STRONG PULSE OF WAA/MSTR TRANSPORT AS 40 KT LLJ
DEVELOPS. MSTR WILL INITIALLY BE LACKING SO IT APPEARS THIS
PROCESS WILL NOT DESTABILIZE THE ATMS. JUST TOO SOON SO THE FCST
IS DRY.
MON-TUE: RISK OF TSTMS INCREASES AND PROBABLY PEAKS TUE. WE ARE
PROBABLY TOO LOW ON OUR TEMPS BY 3-5F. WOULD NOT BE SURPRISED TO SEE
MID 90S SW OF THE TRI-CITIES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 246 PM CDT WED MAY 29 2013
THERE ARE NUMEROUS AVIATION CHALLENGES INCLUDING MULTIPLE ROUNDS
OF THUNDERSTORMS IN AND AROUND KGRI THROUGH THIS EVENING. VARYING
WIND SPEED AND DIRECTION NEAR THUNDERSTORMS WILL ALSO BE A
CONCERN. FURTHERMORE...THERE WILL BE PERIODIC MVFR AND IFR
CONDITIONS DUE TO LOW CLOUDS ASSOCIATED WITH THUNDERSTORMS.
THUNDERSTORMS CONTINUE TO REDEVELOP TO THE SOUTHWEST OF KGRI AND
THESE THUNDERSTORMS WILL SWING THROUGH OR NEAR KGRI THIS
AFTERNOON. ANOTHER INTENSE LINE OF THUNDERSTORMS WILL LIKELY
DEVELOP ACROSS SOUTHWEST NEBRASKA INTO WESTERN KANSAS LATE THIS
AFTERNOON AND WILL PUCH NORTHEAST INTO KGRI THIS EVENING. SEVERE
WEATHER IS POSSIBLE.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR KSZ006-007-017>019.
&&
$$
UPDATE...PFANNKUCH
SHORT TERM...JCB
LONG TERM...HALBLAUB
AVIATION...027
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
559 PM CDT WED MAY 29 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 404 PM CDT WED MAY 29 2013
COMPLEX SCENARIO TONIGHT BUT THE OVERALL MESSAGE LOOKS TO BE A LOW
END THREAT FOR SEVERE THUNDERSTORMS WITH A BETTER THREAT FOR
LOCALIZED HEAVY RAINFALL. CONVECTION CONTINUES TO SKIRT ALONG THE
WESTERN AND EASTERN EDGES OF THE CWA AS CONVECTION IN NEBRASKA
CONTINUES TO WEAKEN AS IT MOVES NORTH. SHEAR VALUES ARE MINIMALLY
SUPPORTIVE OF SEVERE CONVECTION WHILE CAPE VALUES ARE AROUND 1000 TO
1500 J/KG BUT OF THE VERY SKINNY VARIETY. THUS STARTING TO TREND
THINKING TOWARDS THE CONSISTENT HRRR WHICH FOR 5 RUNS IN A ROW HAS
PRODUCED A LARGE MCS WHICH CONGEALS FROM THE CONVECTION THAT IS
CURRENTLY DEVELOPING OVER THE WESTERN HIGH PLAINS. WILL RUN A BLEND
OF HPC/LOW RESOLUTION MODELS ALONG WITH THE HRRR AND RAP OUTPUT.
THE MAIN TAKE FROM THIS IS THAT THERE STILL APPEARS TO BE THE THREAT
FOR STORMS TO PRODUCE LOCALIZED RAINFALL AMOUNTS OF 3 TO 4 INCHES
WITH SLOW STORM MOVEMENT. WITH MOST LOCATIONS FLASH FLOOD GUIDANCE
RIGHT AROUND AN INCH AND A HALF OR A LITTLE MORE FLASH FLOODING WILL
BE A THREAT. THERE IS LIKELY TO BE A LULL IN CONVECTIVE ACTIVITY
LATE TONIGHT INTO TOMORROW MORNING THEN THE POTENTIAL FOR MORE
THUNDERSTORMS TOMORROW AFTERNOON...ESPECIALLY IN NORTHWEST IOWA AND
MAINLY SOUTHEAST PARTS OF SOUTHWEST MINNESOTA. CAPE VALUES JUST A
BIT MORE STOUT TOMORROW AND WIND SHEAR JUST A TOUCH BETTER SO AGAIN
NOT A WIDESPREAD THREAT BUT A THREAT NONETHELESS. LOWS TONIGHT
MAINLY 60 TO 65 WITH HIGHS ON THURSDAY IN THE MID 70S.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 404 PM CDT WED MAY 29 2013
LINGERING CONVECTION FROM DEVELOPMENT ON THURSDAY AFTERNOON WILL BE
SWINGING FAIRLY RAPIDLY THROUGH WITH STRONG PV LOBE LIFTING TO THE
NORTHEAST. MAIN UPPER WAVE WILL BE FAIRLY SLOW TO WOBBLE THROUGH THE
DAKOTAS THROUGH EARLY IN THE WEEKEND...BUT FIRST PART OF THIS PERIOD
WILL INTRODUCE A DRY SLOT AHEAD OF UPPER CIRCULATION THURSDAY NIGHT
INTO EARLY FRIDAY. AREA OF DIV Q BRUSHES UP AGAINST THE FAR
SOUTHEAST LATE AND WHILE BEST CHANCE FOR PRECIPITATION WILL CONTINUE
WELL SOUTHEAST...DID NUDGE A SMALL CHANCE FOR A LIGHT SHOWER INTO
THE FAR SOUTHEAST FOR A FEW HOURS AROUND DAYBREAK ON FRIDAY. IN
GENERAL...THE DRIER AIR WILL WORK THROUGH AREAS SOUTH OF THE UPPER
LOW AND WITH DIMINISHING WINDS ON THURSDAY NIGHT...WILL FIND LOWS
BACK IN THE UPPER 40S TO LOWER 50S FOR MOST.
SEVERAL DETERMINISTIC MODELS INDICATE A WEAK CONVERGENCE BOUNDARY
SLIDING THROUGH THE AREA ON LATER FRIDAY AFTERNOON AND FRIDAY
EVENING. AIRMASS DOES GET SOMEWHAT UNSTABLE...AND APPEARS TO BE
SETUP FOR DECENT MIXING WITH THE WEST TO SOUTHWEST FLOW COMPONENT AT
LOWER LEVELS THROUGH THE DAY. NET EFFECT WILL LIKELY BE AN ALMOST
UNCAPPED PROFILE WITH 400-700 J/KG INSTABILITY AND UNIMPRESSIVE
SHEAR. LIKELY WILL BE THE UNFAVORABLE AND WEAKLY SUBSIDENT LARGER
SCALE THAT WILL KEEP ACTION AT BAY UNTIL LATER INTO THE DIURNAL
CYCLE...WHEN PERHAPS SOME WEAK LOW LEVEL MOISTURE POOLING DUE TO
INDUCING SOMEWHAT STRONGER CONVERGENCE THAN MODEL INDICATED. STILL
WILL BE FAIRLY ISOLATED TO SCATTERED EVEN IT DOES DEVELOP WITH
MOISTURE LIMITATIONS.
AFTER VERY SHORT TERM...LOOKS LIKE LATER FRIDAY NIGHT INTO SATURDAY
WILL BE THE BEST CHANCE FOR PRECIPITATION ACROSS THE AREA...ALBEIT
MUCH LIGHTER THAN SHORTEST RANGE PRECIPITATION. UPPER TROUGH SWINGS
PAST WITH VERY COOL TEMPERATURES ALOFT. SHOULD BE PLENTY OF LOWER
LEVEL SHOWERS EVEN BEHIND PASSAGE OF UPPER WAVE ON SATURDAY
AFTERNOON WHICH CONTINUE TO ROTATE THROUGH NORTHEASTERN CWA.
BLUSTERY AND COOL DAY...WITH HIGHS UPPER 50S TO MID 60S. GFS
ENSEMBLE TEMPERATURE GUIDANCE STRONGLY SUGGESTS THAT COOLER IS
BETTER FOR SATURDAY. WINDS WILL DIMINISH...BUT A COOL NIGHT ON
SATURDAY NIGHT AS CLEARING PUSHES INTO THE WEST HALF.
FOR THE EXTENDED RANGE /SUNDAY THROUGH WEDNESDAY/ A FAIRLY QUIET
START WITH BRIEF RIDGING IN PLACE. STRETCHED OUT THE DIURNAL RANGE A
BIT FROM INITIALIZATION...AS EVEN WITH WET GROUND SHOULD BE ABLE TO
GET TOWARD FULL 850 HPA MIXING ON SUNDAY. DEVELOPMENT OF RETURN FLOW
FROM WEST TO EAST ON SUNDAY NIGHT INTO MONDAY MORNING. GFS/ECMWF
SHOWING SOME WEAK ELEVATED INSTABILITY/MOISTURE RETURN BY LATER
MONDAY...AND RELUCTANTLY INTRODUCED A LOW CHANCE FOR THUNDERSTORMS.
ANOTHER UPPER TROUGH WILL SETTLE INTO THE NORTHERN PLAINS TUESDAY
INTO WEDNESDAY...BUT THIS SOURCE WILL BE WITHIN LARGER SCALE
NORTHWEST FLOW AND IS SOMEWHAT MORE PROGRESSIVE THAN SHORT TERM
SYSTEM. SOME UNCERTAINTY IN TIMING AS BOUNDARY PUSHES THROUGH THE
AREA BUT HIGHEST CHANCES APPEAR CURRENTLY TO WORK THROUGH DURING THE
MONDAY NIGHT THROUGH TUESDAY NIGHT PERIOD. GENERALLY...TEMPERATURES
WILL BE WORKING SLOWLY UPWARD THROUGH TUESDAY...THEN SLIPPING BACK A
TOUCH WITH BOUNDARY PASSAGE AND PRECIPITATION LATER TUESDAY INTO
WEDNESDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 559 PM CDT WED MAY 29 2013
A MORE ORGANIZED ROUND OF THUNDERSTORMS WILL PUSH SSW TO NNE
ACROSS THE AREA THIS MID TO LATE EVENING...AFFECTING THE
HON/FSD/SUX TAF SITES. MVFR CONDITIONS ARE EXPECTED WITH THESE
STORMS...AND SOME WILL CONTAIN LARGE HAIL AND VERY STRONG WIND
GUSTS TO 50+ KTS. A MOIST AIRMASS WILL SETTLE OVER THE REGION
AGAIN LATE TONIGHT/EARLY THURSDAY WITH WIDESPREAD IFR CONDITIONS
LOOKING LIKELY.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR SDZ061-062-066-
067-070-071.
MN...NONE.
IA...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR IAZ001>003-
012>014-020>022-031-032.
NE...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR NEZ013-014.
&&
$$
SHORT TERM...08
LONG TERM...CHAPMAN
AVIATION...
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
404 PM CDT WED MAY 29 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 404 PM CDT WED MAY 29 2013
COMPLEX SCENARIO TONIGHT BUT THE OVERALL MESSAGE LOOKS TO BE A LOW
END THREAT FOR SEVERE THUNDERSTORMS WITH A BETTER THREAT FOR
LOCALIZED HEAVY RAINFALL. CONVECTION CONTINUES TO SKIRT ALONG THE
WESTERN AND EASTERN EDGES OF THE CWA AS CONVECTION IN NEBRASKA
CONTINUES TO WEAKEN AS IT MOVES NORTH. SHEAR VALUES ARE MINIMALLY
SUPPORTIVE OF SEVERE CONVECTION WHILE CAPE VALUES ARE AROUND 1000 TO
1500 J/KG BUT OF THE VERY SKINNY VARIETY. THUS STARTING TO TREND
THINKING TOWARDS THE CONSISTENT HRRR WHICH FOR 5 RUNS IN A ROW HAS
PRODUCED A LARGE MCS WHICH CONGEALS FROM THE CONVECTION THAT IS
CURRENTLY DEVELOPING OVER THE WESTERN HIGH PLAINS. WILL RUN A BLEND
OF HPC/LOW RESOLUTION MODELS ALONG WITH THE HRRR AND RAP OUTPUT.
THE MAIN TAKE FROM THIS IS THAT THERE STILL APPEARS TO BE THE THREAT
FOR STORMS TO PRODUCE LOCALIZED RAINFALL AMOUNTS OF 3 TO 4 INCHES
WITH SLOW STORM MOVEMENT. WITH MOST LOCATIONS FLASH FLOOD GUIDANCE
RIGHT AROUND AN INCH AND A HALF OR A LITTLE MORE FLASH FLOODING WILL
BE A THREAT. THERE IS LIKELY TO BE A LULL IN CONVECTIVE ACTIVITY
LATE TONIGHT INTO TOMORROW MORNING THEN THE POTENTIAL FOR MORE
THUNDERSTORMS TOMORROW AFTERNOON...ESPECIALLY IN NORTHWEST IOWA AND
MAINLY SOUTHEAST PARTS OF SOUTHWEST MINNESOTA. CAPE VALUES JUST A
BIT MORE STOUT TOMORROW AND WIND SHEAR JUST A TOUCH BETTER SO AGAIN
NOT A WIDESPREAD THREAT BUT A THREAT NONETHELESS. LOWS TONIGHT
MAINLY 60 TO 65 WITH HIGHS ON THURSDAY IN THE MID 70S.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 404 PM CDT WED MAY 29 2013
LINGERING CONVECTION FROM DEVELOPMENT ON THURSDAY AFTERNOON WILL BE
SWINGING FAIRLY RAPIDLY THROUGH WITH STRONG PV LOBE LIFTING TO THE
NORTHEAST. MAIN UPPER WAVE WILL BE FAIRLY SLOW TO WOBBLE THROUGH THE
DAKOTAS THROUGH EARLY IN THE WEEKEND...BUT FIRST PART OF THIS PERIOD
WILL INTRODUCE A DRY SLOT AHEAD OF UPPER CIRCULATION THURSDAY NIGHT
INTO EARLY FRIDAY. AREA OF DIV Q BRUSHES UP AGAINST THE FAR
SOUTHEAST LATE AND WHILE BEST CHANCE FOR PRECIPITATION WILL CONTINUE
WELL SOUTHEAST...DID NUDGE A SMALL CHANCE FOR A LIGHT SHOWER INTO
THE FAR SOUTHEAST FOR A FEW HOURS AROUND DAYBREAK ON FRIDAY. IN
GENERAL...THE DRIER AIR WILL WORK THROUGH AREAS SOUTH OF THE UPPER
LOW AND WITH DIMINISHING WINDS ON THURSDAY NIGHT...WILL FIND LOWS
BACK IN THE UPPER 40S TO LOWER 50S FOR MOST.
SEVERAL DETERMINISTIC MODELS INDICATE A WEAK CONVERGENCE BOUNDARY
SLIDING THROUGH THE AREA ON LATER FRIDAY AFTERNOON AND FRIDAY
EVENING. AIRMASS DOES GET SOMEWHAT UNSTABLE...AND APPEARS TO BE
SETUP FOR DECENT MIXING WITH THE WEST TO SOUTHWEST FLOW COMPONENT AT
LOWER LEVELS THROUGH THE DAY. NET EFFECT WILL LIKELY BE AN ALMOST
UNCAPPED PROFILE WITH 400-700 J/KG INSTABILITY AND UNIMPRESSIVE
SHEAR. LIKELY WILL BE THE UNFAVORABLE AND WEAKLY SUBSIDENT LARGER
SCALE THAT WILL KEEP ACTION AT BAY UNTIL LATER INTO THE DIURNAL
CYCLE...WHEN PERHAPS SOME WEAK LOW LEVEL MOISTURE POOLING DUE TO
INDUCING SOMEWHAT STRONGER CONVERGENCE THAN MODEL INDICATED. STILL
WILL BE FAIRLY ISOLATED TO SCATTERED EVEN IT DOES DEVELOP WITH
MOISTURE LIMITATIONS.
AFTER VERY SHORT TERM...LOOKS LIKE LATER FRIDAY NIGHT INTO SATURDAY
WILL BE THE BEST CHANCE FOR PRECIPITATION ACROSS THE AREA...ALBEIT
MUCH LIGHTER THAN SHORTEST RANGE PRECIPITATION. UPPER TROUGH SWINGS
PAST WITH VERY COOL TEMPERATURES ALOFT. SHOULD BE PLENTY OF LOWER
LEVEL SHOWERS EVEN BEHIND PASSAGE OF UPPER WAVE ON SATURDAY
AFTERNOON WHICH CONTINUE TO ROTATE THROUGH NORTHEASTERN CWA.
BLUSTERY AND COOL DAY...WITH HIGHS UPPER 50S TO MID 60S. GFS
ENSEMBLE TEMPERATURE GUIDANCE STRONGLY SUGGESTS THAT COOLER IS
BETTER FOR SATURDAY. WINDS WILL DIMINISH...BUT A COOL NIGHT ON
SATURDAY NIGHT AS CLEARING PUSHES INTO THE WEST HALF.
FOR THE EXTENDED RANGE /SUNDAY THROUGH WEDNESDAY/ A FAIRLY QUIET
START WITH BRIEF RIDGING IN PLACE. STRETCHED OUT THE DIURNAL RANGE A
BIT FROM INITIALIZATION...AS EVEN WITH WET GROUND SHOULD BE ABLE TO
GET TOWARD FULL 850 HPA MIXING ON SUNDAY. DEVELOPMENT OF RETURN FLOW
FROM WEST TO EAST ON SUNDAY NIGHT INTO MONDAY MORNING. GFS/ECMWF
SHOWING SOME WEAK ELEVATED INSTABILITY/MOISTURE RETURN BY LATER
MONDAY...AND RELUCTANTLY INTRODUCED A LOW CHANCE FOR THUNDERSTORMS.
ANOTHER UPPER TROUGH WILL SETTLE INTO THE NORTHERN PLAINS TUESDAY
INTO WEDNESDAY...BUT THIS SOURCE WILL BE WITHIN LARGER SCALE
NORTHWEST FLOW AND IS SOMEWHAT MORE PROGRESSIVE THAN SHORT TERM
SYSTEM. SOME UNCERTAINTY IN TIMING AS BOUNDARY PUSHES THROUGH THE
AREA BUT HIGHEST CHANCES APPEAR CURRENTLY TO WORK THROUGH DURING THE
MONDAY NIGHT THROUGH TUESDAY NIGHT PERIOD. GENERALLY...TEMPERATURES
WILL BE WORKING SLOWLY UPWARD THROUGH TUESDAY...THEN SLIPPING BACK A
TOUCH WITH BOUNDARY PASSAGE AND PRECIPITATION LATER TUESDAY INTO
WEDNESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1239 PM CDT WED MAY 29 2013
ROUGH SET OF TAF FORECASTS THIS GO AROUND WITH SCATTERED SHOWERS
AND THUNDERSTORMS ACROSS THE ENTIRE FORECAST AREA. THESE SHOWERS
AND THUNDERSTORMS ARE SHORT LIVED AND ANY ONE LOCATION NOT LIKELY
TO HAVE MORE THAN 15 TO 30 MINUTES OF RAIN/THUNDER SO WITH NO REAL
EASY WAY TO GET THIS POINT ACROSS IN A TAF FORECAST WILL LEAVE OUT
FOR NOW. WILL HOWEVER HIT THUNDER AND RAIN A LITTLE HARDER AFTER
0Z AS A POTENTIALLY MORE ORGANIZED AREA OF THUNDERSTORMS SHOULD
MOVE NORTHEAST FROM NEBRASKA. THESE STORMS WILL HAVE SOME
POTENTIAL TO PRODUCE STRONG WINDS...ESPECIALLY FROM ABOUT 1Z
THROUGH 5Z. WIDESPREAD MVFR CONDITIONS EXPECTED WITH SOME IFR
CEILINGS POSSIBLE AFTER ABOUT 6Z.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR SDZ061-062-066-
067-070-071.
MN...NONE.
IA...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR IAZ001>003-
012>014-020>022-031-032.
NE...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR NEZ013-014.
&&
$$
SHORT TERM...08
LONG TERM...CHAPMAN
AVIATION...08
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1214 PM CDT WED MAY 29 2013
.UPDATE...
18Z TAF DISCUSSION.
&&
.AVIATION...
SURFACE OBS INDICATE DEWPOINTS HAVE RISEN INTO THE 60S
AREAWIDE...AND SATELLITE IMAGERY SHOWS A CORRESPONDING EXTENSIVE
CUMULUS FIELD HAS FORMED ACROSS THE MID STATE. EXPECT SCT-BKN VFR
CIGS THIS AFTERNOON BUT NO -SHRA/-TSRA IS ANTICIPATED NEAR
AIRPORTS. SFC WIND DIRECTION HAS BEEN VARYING WILDLY BETWEEN
SOUTHEAST AND WEST THIS MORNING...AND HAVE COMPROMISED WITH A SW
TO SSW DIRECTION FOR TAFS. SPEEDS OF 5 TO 11 KTS WITH OCCASIONAL
GUSTS UP TO 20 KTS POSSIBLE. WINDS WILL ONLY SLIGHTLY SUBSIDE
OVERNIGHT AS SOUTHERLY LLJ INCREASES TO 25-35 KTS.
SHAMBURGER
&&
.PREV DISCUSSION... /ISSUED 906 AM CDT WED MAY 29 2013/
UPDATE...
TEMPERATURES ARE WARMING QUICKLY THIS MORNING WITH MOST SURFACE
OBS ALREADY WELL INTO THE 70S TO NEAR 80. FORECAST HIGHS TEMPS IN
THE LOW 80S ON THE PLATEAU AND UPPER 80S ELSEWHERE STILL LOOK ON
TRACK...AND A FEW LOCATIONS COULD TOUCH THE 90 DEGREE MARK THIS
AFTERNOON. SATELLITE IMAGERY AND REGIONAL SURFACE OBS SHOW AN
AREA OF DEEPER MOISTURE SPREADING NORTHWESTWARD ACROSS
MISSISSIPPI/ALABAMA WITH PWATS UP TO 1.50 INCHES PER 12Z LIX
SOUNDING. THIS MOISTURE WILL ENTER WESTERN TENNESSEE LATER
TODAY...AND A COUPLE OF MODELS LIKE THE HRRR AND 4.0 KM WRF
INDICATE AN ISOLATED SHOWER IS NOT OUT OF THE QUESTION ALONG OUR
WESTERN AND SOUTHWESTERN CWA BORDERS. HOWEVER...RISING HEIGHTS
ALOFT ACROSS THE MID STATE DUE TO THE LARGE TROUGH EJECTING OUT
INTO THE PLAINS COMBINED WITH SUBSTANTIAL DRY AIR THROUGHOUT THE
COLUMN IS EXPECTED TO SUPPRESS CONVECTIVE DEVELOPMENT AND WILL
LEAVE INHERITED DRY FORECAST AS IS. REST OF FORECAST ALSO REMAINS
ON TRACK AND NO CHANGES WERE MADE.
SHAMBURGER
PREV DISCUSSION... /ISSUED 330 AM CDT WED MAY 29 2013/
DISCUSSION...
UPPER RIDGING EXTENDS FROM JUST SOUTH OF BERMUDA IN THE ATLANTIC NW
THROUGH GA AND TN. UPPER TROUGH MOVING EAST ACROSS THE NORTHERN
ROCKIES WITH A GENERAL SW FLOW ALOFT FROM TX NE TO THE GREAT LAKES.
THE AFOREMENTIONED UPPER TROUGH WILL CONTINUE TO MOVE EAST AND WE
WILL SEE THE RIDGE AXIS SHIFT EAST AS WELL. THOUGH 18Z CAP EROSION
IS PRONOUNCED TODAY...MRH LEVELS ARE RATHER LOW AND CAPES AS WELL.
NOT SEEING MUCH IN THE WAY OF CONVECTIVE DEVELOPMENT ACROSS THE MID
STATE. HOWEVER...AS WE BEGIN TO GET MORE AND MORE INTO THE SW FLOW
ALOFT IN THE DAYS TO COME...CAPES AND MOISTURE WILL BE ON THE
INCREASE. LOW POPS WILL BE NEEDED ON THURSDAY AND WILL SLOWLY
INCREASE INTO THE WEEKEND. TEMPERATURES WILL CONTINUE TO RUN A
LITTLE ABOVE NORMAL...BUT ANY ENHANCED THERMAL RIDGING SHOULD REMAIN
CONFINED TO OLD MEXICO.
VERSUS THE NEAR TERM GUIDANCE...WILL ELECT TO DIFFER LITTLE IF ANY
FROM THE MAV. MET DATA LOOKING A LITTLE TOO LOW WITH DAY TIME
HIGHS.
IN THE EXT FCST...STILL EXPECTING THE COLD FRONT TO APPROACH THIS
WEEKEND WITH THE FROPA OCCURRING SUNDAY NIGHT. THUS...POPS WILL BE
HIGHEST SAT NT AND SUNDAY. STILL LOOKING AT THE POSSIBILITY OF A FEW
STRONG STORMS FOR SAT AND SUN DURING THE AFT/EVE HOURS. SLIGHTLY
COOLER AND DRIER AIR IS EXPECTED BY TUESDAY BEHIND THE FRONT. WILL
LEAN TOWARD THE SLIGHTLY COOLER EURO MOS THROUGH MUCH OF THE
EXTENDED.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
254 PM PDT Wed May 29 2013
.SYNOPSIS...
Low pressure aloft will keep a chance for showers Thursday with
the highest threat for rain focusing over the northern and
eastern mountains. Most of the region will experience dry
conditions Friday coupled with warming temperatures. The warming
trend will continue into the weekend with a few weak disturbances
expected to clip far northeastern Washington and the Idaho
Panhandle keeping a small chance for showers in the forecast.
&&
.DISCUSSION...
Tonight...Slow moving upper level shortwave trough will remain
the dominant feature for tonight`s weather. As of 2pm...the base
of the trough was located near the Tri-Cities and was moving
slowly to the east-northeast. A NW-SE band of precipitation ahead
of the trough will deliver stratiform precipitation to locations
over NE Washington and much of the Idaho Panhandle through early
evening. Strangely enough this band moved over the Spokane area
and generally fell apart...but it remains intact to the northwest
and southeast. This band will likely weaken during the
evening...and most of the precipitation then will result from the
unstable conditions behind the band. The HRRR model continues to
forecast SBCAPE values between 300-700 j/kg over the southern
Columbia Basin near the negatively tilted trough axis through this
afternoon...before shifting it toward the WA/ID border by early
evening. This roughly matches whats transpiring on the latest
radar and satellite imagery with a line of showers and embedded
thunderstorms developing along a line from Mattawa to Walla Walla.
The threat of thunderstorms will likely persist through mid-
evening before tapering off overnight. Meanwhile elevated
instability ahead of the trough could still result in a few
showers through the night especially over extreme NE Washington
and the Idaho Panhandle. fx
Thursday through Saturday night: A northwest to southeast oriented
upper-level trof will remain anchored over the Inland NW Thursday
then begin a slow migration northward Friday and Saturday. This
will keep the threat for showers across the region on Thursday
with a drying trend for Friday. Another weak wave will track
across northern WA/ID late Saturday/Saturday night bringing a
small chance for showers but for the most part...most locations will
continue to experience generally dry conditions.
For Thursday, 500mb temperatures around -20C within the inner trof
will keep a pool of instability over the region. This is expected
to equate to widely scattered afternoon showers. The northern and
eastern mountains...expanding into the upper Columbia Basin will
carry the highest threat for precipitation. Across the southern
Columbia Basin and East Slopes...tightening pressure gradients
will bring a slight increase in winds which should help dry out
the boundary layer...resulting in decreasing surface based
instability and lowering chances for showers through the
afternoon. The trof will begin to migrate northward on Friday with
models indicating almost 6C of warming aloft (500mb). With the exception
of the far northern mountains...a dry day is in store for most and
only the ECMWF lingers enough instability over the northern
mountains to keep a slight chance of showers in the forecast. On
Saturday, a ridge of high pressure begins to amplify over the Gulf
of AK allowing a shortwave to drop into the region from the
northwest. This does not look like a very wet system but will
bring a slight increase in the threat for showers mainly north of
a line from Kellogg to Omak through the Saturday evening and
night time-frame.
Temperatures through the period will start off below normal and
slowly warm near normal by the weekend. This equates to highs in
60`s to low 70`s Thursday...warming into the 70`s to low 80`s
on Saturday. A few cold pockets within the northern mountains will
continue to drop into the 30`s at night but are expected to remain
just above freezing. /sb
Sunday through Wednesday: Models are in pretty good agreement of
an upper level low pressure system pushing through the Inland
Northwest Sunday. Latest ECMWF is a bit more robust and further
south with the low...bringing it along the WA/Canadian border. GFS
seems to be trending more towards an unsettled day as well. There are
still some discrepancies with this feature though. Have increased
chance of precipitation from the Spokane area north towards the
Canadian border and east to the MT state line for the afternoon and
early evening hours. There is even some instability associated
with the system moving through. For now have kept mention of
thunder out of the forecast, but will need to be evaluated again
as models come more in line with each other. Monday the trough
moves out of the area but showers are still possible along the
Idaho Panhandle. Tuesday and Wednesday a ridge of high pressure
will move into the Pacific Northwest. Have decreased chance of
precipitation and sky cover. Temperatures Sunday will be below average
and then trend to average by Monday and above average for Tue and
Wed. /Nisbet
&&
.AVIATION...
18Z TAFS: VFR conditions are expected at all the sites through
most of the period. Brief MVFR cigs will be possible however as a
NW-SE oriented band of rain moves through E WA and the ID
Panhandle this afternoon. The band has already moved through MWH
and EAT...but showers and even a thunderstorm will be possible
between 21z-01z at those sites. The band is expected to weaken
overnight...clearing PUW and LWS early this evening and GEG-COE
sometime after 03z. The threat of precip will ease for all sites
during the overnight hours and then the main risk is seeing a MVFR
or possibly an IFR stratus deck form over EC Washington late
tonight. The atmospheric setup is right for a band to form
somewhere over the eastern Columbia Basin...the question is will
it hit any of the airports. We put in a sct deck of clouds between
008-011 feet and have it impacting KGEG-KCOE aft 12z...but this
could prove underdone. fx
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 43 62 44 67 45 71 / 70 20 20 0 0 10
Coeur d`Alene 44 60 42 67 42 71 / 70 30 20 10 0 10
Pullman 41 58 40 66 41 71 / 70 20 10 0 0 0
Lewiston 46 68 46 73 47 79 / 60 20 10 0 0 0
Colville 47 65 43 74 43 75 / 80 50 20 10 0 20
Sandpoint 45 58 42 67 40 70 / 70 60 30 10 10 10
Kellogg 42 55 41 62 43 68 / 70 50 30 10 0 10
Moses Lake 46 72 46 74 47 78 / 50 10 0 0 0 10
Wenatchee 46 71 49 74 50 76 / 50 10 0 0 0 10
Omak 45 68 43 74 45 76 / 60 20 10 10 0 20
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1153 AM PDT Wed May 29 2013
.SYNOPSIS...
Widespread rain is expected over the Inland Northwest today as an
upper level disturbance moves through the region. Widely scattered
thunderstorms will be possible this afternoon as well. The best
chances for rain showers on Thursday will be over the Idaho
Panhandle. The weekend should be a bit warmer than average with a
chance for showers over the Idaho Panhandle once again.
&&
.DISCUSSION...
rest of today...fairly potent shortwave trough will be the main
focus for the weather this afternoon. Looking at the latest water
vapor image it suggests the base of the trough was located near
Hermiston and moving slowly east-northeast. So far most of the
precipitation from this trough was situated along a NW-SE
deformation band extending from the north Washington Cascades
toward Lewiston. The band is expected to drift NE through the
afternoon...however its progress will likely be slowed as the base
of the trough takes its time meandering near the WA/OR border.
There is some doubt whether this band will make it into the
northern third of the Idaho Panhandle by afternoon. The slower it
arrives...the better the chance of sparking some deep convection
due to diurnal heating from mostly sunny skies. Not sure there is
enough instability to produce a thunderstorm...but there is
certainly enough for showers. Locations on the backside of the
band...over the western Columbia Basin...Wenatchee
Area...Waterville Plateau...will see a brief break in the rain
threat...however another band of precipitation...currently over NC
Oregon will impact that region by this afternoon. Suspect this is
the region that will see the best chance of sparking a thunderstorm this
afternoon...as the RUC and the HRRR have consistently been
forecasting the highest CAPE values with little if any convective
inhibition. This threat of thunder will likely taper off early
this evening as the base of the trough begins to lift northeast.
The considerable cloudiness associated with the deformation band other
update for today was adjusting max temperatures down in some of
the areas which will be impacted by the deformation band. fx
&&
.AVIATION...
18Z TAFS: VFR conditions are expected at all the sites through
most of the period. Brief MVFR cigs will be possible however as a
NW-SE oriented band of rain moves through E WA and the ID
Panhandle this afternoon. The band has already moved through MWH
and EAT...but showers and even a thunderstorm will be possible
between 21z-01z at those sites. The band is expected to weaken
overnight...clearing PUW and LWS early this evening and GEG-COE
sometime after 03z. The threat of precip will ease for all sites
during the overnight hours and then the main risk is seeing a MVFR
or possibly an IFR stratus deck form over EC Washington late
tonight. The atmospheric setup is right for a band to form
somewhere over the eastern Columbia Basin...the question is will
it hit any of the airports. We put in a sct deck of clouds between
008-011 feet and have it impacting KGEG-KCOE aft 12z...but this
could prove underdone. fx
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 60 45 62 44 67 46 / 80 40 20 20 0 0
Coeur d`Alene 63 45 61 42 67 43 / 70 50 30 20 10 0
Pullman 58 43 61 40 66 42 / 80 30 20 10 0 0
Lewiston 63 47 68 46 73 48 / 80 30 20 10 0 0
Colville 68 46 68 43 74 43 / 80 50 50 20 10 0
Sandpoint 64 45 59 41 67 40 / 60 60 60 30 10 10
Kellogg 60 44 56 42 62 44 / 80 70 50 30 10 0
Moses Lake 64 47 72 45 74 47 / 70 20 10 0 0 0
Wenatchee 62 48 69 48 73 50 / 70 20 10 0 0 0
Omak 64 45 70 43 74 45 / 80 30 20 10 10 0
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
429 PM CDT WED MAY 29 2013
.UPDATE...
ISSUED AT 429 PM CDT WED MAY 29 2013
HAVE EXPANDED THE FLASH FLOOD WATCH EASTWARD TO INCLUDE
HOUSTON...ALLAMAKEE AND CLAYTON COUNTIES. PRESENT CONVECTION
TRACKING ACROSS WESTERN PORTIONS OF THE FORECAST AREA HAS BEEN
MOVING MORE SLOWLY ACROSS NORTHEAST IOWA...PRIMARILY DUE TO LOWER
0-6KM SHEAR THERE. AS THIS CONVECTION MOVES INTO THE EXPANSION
AREA...EXPECTING THE RAIN TO PRIME CONDITIONS FOR POSSIBLE FLASH
FLOODING...EITHER FROM THE CURRENT CONVECTION OR FROM ADDITIONAL
EXPECTED CONVECTION LATER TONIGHT INTO THURSDAY. ALSO STARTED THE
FLASH FLOOD WATCH NOW GIVEN CURRENT CONVECTION AND THE NEED FOR
WARNINGS SOONER THAN EXPECTED.
&&
.SHORT TERM...(TONIGHT THROUGH THURSDAY)
ISSUED AT 308 PM CDT WED MAY 29 2013
MAIN CONCERN IS SEVERE POTENTIAL GOING INTO THIS EVENING AND HEAVY
RAINFALL POTENTIAL THROUGH THURSDAY.
WATER VAPOR IMAGERY/RAP 500MB ANALYSIS SHOWS A DEEPENING TROUGH OF
LOW PRESSURE ACROSS THE CENTRAL ROCKIES INTO THE SOUTHERN PLAINS.
THIS IN TURN WAS DRIVING AN INCREASINGLY MOIST/UNSTABLE SOUTHERLY
SURFACE FLOW FROM THE PLAINS INTO THE UPPER MISSISSIPPI RIVER VALLEY
REGION. AT THE SURFACE LOW PRESSURE WAS LOCATED OVER SOUTHEAST CO
WITH A WARM FRONT EXTENDING NORTHEAST THROUGH IA INTO SOUTHERN WI.
CONVECTION/SOME STRONG TO SEVERE WAS FIRING ALONG/AHEAD OF THIS WARM
FRONT ON THE NOSE OF INCREASING 925-85OMB MOISTURE
TRANSPORT/INCREASING CAPE POOL. DEW POINTS ACROSS OUR AREA THIS
AFTERNOON WERE IN THE MID/UPPER 60S WITH AROUND 70 ACROSS EASTERN
IA.
LOOK FOR ONGOING SHOWER/THUNDERSTORM ACTIVITY THIS EVENING AS THE
WARM FRONT/NOSE OF RATHER INTENSE MOISTURE TRANSPORT CONTINUES TO PUSH NORTH
ACROSS THE AREA. RAP SHOWING 0-1KM MLCAPE IN THE 3000-3500J/KG WITH
INCREASING 0-3KM BULK SHEAR IN THE 25-35KT RANGE BETWEEN 4 PM AND 8
PM ACROSS PORTIONS OF NORTHEAST IA/SOUTHWEST WI. CAPE/BULK SHEAR AND
ENHANCED 0-1KM EHI VALUES WOULD FAVOR TORNADOGENESIS ALONG THE WARM
FRONT AS IT PUSHES THROUGH NORTHEAST IA/SOUTHWEST WI. WILL HAVE TO
KEEP AN EYE ON LARGE HAIL/DAMAGING WIND/TORNADIC POTENTIAL GOING INTO
EVENING. CAPE STARTS DWINDLING AFTER SUNSET...HOWEVER...MODELS
CONTINUE TO SHOW FETCH OF STRONG 925-850MB MOISTURE TRANSPORT
ADVECTING INTO OUR AREA OVERNIGHT INTO THURSDAY. THIS WILL BE AHEAD
OF A COLD FRONT PUSHING EASTWARD INTO THE CENTRAL PLAINS.
PRECIPITABLE WATER VALUES INCREASE INTO THE 1.5 TO 1.7IN RANGE. WITH
THIS IN MIND THERE WILL BE THE POTENTIAL WILL BE THERE FOR SOME
HEAVY RAINFALL. HAVE ISSUED A FLASH FLOOD WATCH FOR PORTIONS OF THE
AREA THIS EVENING THROUGH THURSDAY TO COVER THIS. SEE THE HYDROLOGY
SECTION BELOW FOR FURTHER DETAILS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 308 PM CDT WED MAY 29 2013
MAIN AXIS OF MOISTURE TRANSPORT/ENHANCED PRECIPITABLE WATER SHIFTS
EAST OF THE AREA THURSDAY NIGHT WITH A COLD FRONT LAGGING ACROSS
CENTRAL MN INTO EASTERN NEBRASKA/CENTRAL KS. SO...EXPECTING HEAVIER
RAINFALL TO TAPER OFF IN THE EVENING/OVERNIGHT FROM WEST TO EAST.
THE COLD FRONT WILL CONTINUE TO PUSH SLOWLY EAST INTO THE AREA
FRIDAY WITH INCREASING MOISTURE TRANSPORT INTO FAR SOUTHERN WI
DURING THE AFTERNOON. HAVE TAILORED SHRA/TS CHANCES WITH LIKELY
ACROSS THE SOUTH...TAPERING TO 40-50 POPS ACROSS THE NORTHWEST.
FOR FRIDAY NIGHT THROUGH SUNDAY...LOOK FOR A MID-LEVEL CLOSED LOW TO
MAKE ITS WAY ACROSS THE AREA FOR SCATTERED SHOWERS AND COOLING
TEMPERATURES.
SUNDAY NIGHT THROUGH MONDAY LOOKS DRY AND COOL AS A RIDGE OF HIGH
PRESSURE BUILDS IN FROM THE PLAINS.
SHOWER/THUNDERSTORM CHANCES RETURN TO THE AREA MONDAY NIGHT THROUGH
WEDNESDAY AS ANOTHER CLOSED MID-LEVEL LOW SYSTEM DROPS ACROSS THE
NORTHERN PLAINS INTO THE UPPER MISSISSIPPI RIVER REGION. THIS SYSTEM
WILL ALSO RESULT IN BELOW NORMAL TEMPERATURES THROUGH THIS PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED
AT 1233 PM CDT WED MAY 29 2013
THE WARM FRONT HAS PUSHED NORTH OF THE TAF SITES...WITH A WARM...
MOIST AND UNSTABLE AIRMASS OVERSPREADING SOUTHERN MN/WESTERN WI.
CLOUDS ALONG/SOUTH OF THE FRONT HAVE GENERALLY CLEARED OUT/BECOME
SCATTERED WITH THE MAIN FOCUS FOR SHRA/TSRA REMAINING WEST OF THE
AREA EARLY THIS AFTERNOON...PROVIDING A PERIOD OF IMPROVED VFR
CONDITIONS THRU MID TO LATE AFTERNOON.
MAIN FORCING/LIFT AND DEEPER MOISTURE CONTINUE TO SPREAD NORTHEAST
AND EAST ACROSS THE AREA LATER THIS AFTERNOON THRU TONIGHT INTO
THURSDAY. SHRA/TSRA CHANCES/TIMING IN THE SUMMERY AIRMASS OVER-
SPREADING THE AREA REMAIN PROBLEMATIC AFTER THE 20-23Z TIME-FRAME
THIS AFTERNOON THRU THU. APPEARS ONE ROUND OF SHRA/TSRA TO MOVE
ACROSS THE TAF SITES IN THE 20-03Z TIME PERIOD LATER TODAY.
CONFIDENCE MODERATE ON THIS ROUND. ANOTHER ROUND OF SHRA/TSRA LOOKS
TO MOVE ACROSS THE TAF SITES LATER TONIGHT/THU MORNING. GIVEN A WIDE
VARIETY OF SMALL SCALE TRIGGERS AND MODEL SOLUTIONS...CONFIDENCE
LOWER LATER TONIGHT/THU. OPTED NOT TO SPREAD EXTENSIVE PERIODS OF
TSRA/CB IN THE TAFS FOR NOW GIVEN MDT CONFIDENCE AT BEST. WILL JUST
HAVE TO PLAN ON SOME AMD/UPDATES ONCE TIMING/COVERAGE OF THE ROUNDS
OF CONVECTION BECOME CLEARER.
&&
.HYDROLOGY...TONIGHT THROUGH FRIDAY
ISSUED AT 429 PM CDT WED MAY 29 2013
PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED ACROSS MUCH OF THE
REGION THROUGH FRIDAY. THE HEAVIEST RAIN IS EXPECTED TO FALL FROM
THURSDAY INTO FRIDAY. TOTAL RAINFALL FROM TODAY THROUGH FRIDAY
COULD RANGE FROM 1 TO 3 INCHES WITH LOCALLY HIGHER AMOUNTS
POSSIBLE. THIS COULD LEAD TO FLASH FLOODING AS WELL AS RISES AND
POSSIBLE FLOODING ON AREA RIVERS. A FLASH FLOOD WATCH HAS BEEN
ISSUED FOR NORTHEAST IA AND PORTIONS OF SOUTHEAST MN THROUGH THU.
THIS MAY NEED TO BE EXPANDED NORTHWARD...OR POSSIBLY EVEN EASTWARD
INTO WI...AS DETAILS OF TIMING/LOCATION OF THE CONTINUED HEAVY
RAIN THREAT BECOME CLEARER.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...FLASH FLOOD WATCH THROUGH THURSDAY EVENING FOR MNZ094>096.
IA...FLASH FLOOD WATCH THROUGH THURSDAY EVENING FOR IAZ008>011-018-
019-029-030.
&&
$$
UPDATE...AJ
SHORT TERM...DAS
LONG TERM....DAS
AVIATION.....RRS
HYDROLOGY....DAS/AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
308 PM CDT WED MAY 29 2013
.SHORT TERM...(TONIGHT THROUGH THURSDAY)
ISSUED AT 308 PM CDT WED MAY 29 2013
MAIN CONCERN IS SEVERE POTENTIAL GOING INTO THIS EVENING AND HEAVY
RAINFALL POTENTIAL THROUGH THURSDAY.
WATER VAPOR IMAGERY/RAP 500MB ANALYSIS SHOWS A DEEPENING TROUGH OF
LOW PRESSURE ACROSS THE CENTRAL ROCKIES INTO THE SOUTHERN PLAINS.
THIS IN TURN WAS DRIVING AN INCREASINGLY MOIST/UNSTABLE SOUTHERLY
SURFACE FLOW FROM THE PLAINS INTO THE UPPER MISSISSIPPI RIVER VALLEY
REGION. AT THE SURFACE LOW PRESSURE WAS LOCATED OVER SOUTHEAST CO
WITH A WARM FRONT EXTENDING NORTHEAST THROUGH IA INTO SOUTHERN WI.
CONVECTION/SOME STRONG TO SEVERE WAS FIRING ALONG/AHEAD OF THIS WARM
FRONT ON THE NOSE OF INCREASING 925-85OMB MOISTURE
TRANSPORT/INCREASING CAPE POOL. DEW POINTS ACROSS OUR AREA THIS
AFTERNOON WERE IN THE MID/UPPER 60S WITH AROUND 70 ACROSS EASTERN
IA.
LOOK FOR ONGOING SHOWER/THUNDERSTORM ACTIVITY THIS EVENING AS THE
WARM FRONT/NOSE OF RATHER INTENSE MOISTURE TRANSPORT CONTINUES TO PUSH NORTH
ACROSS THE AREA. RAP SHOWING 0-1KM MLCAPE IN THE 3000-3500J/KG WITH
INCREASING 0-3KM BULK SHEAR IN THE 25-35KT RANGE BETWEEN 4 PM AND 8
PM ACROSS PORTIONS OF NORTHEAST IA/SOUTHWEST WI. CAPE/BULK SHEAR AND
ENHANCED 0-1KM EHI VALUES WOULD FAVOR TORNADOGENESIS ALONG THE WARM
FRONT AS IT PUSHES THROUGH NORTHEAST IA/SOUTHWEST WI. WILL HAVE TO
KEEP AN EYE ON LARGE HAIL/DAMAGING WIND/TORNADIC POTENTIAL GOING INTO
EVENING. CAPE STARTS DWINDLING AFTER SUNSET...HOWEVER...MODELS
CONTINUE TO SHOW FETCH OF STRONG 925-850MB MOISTURE TRANSPORT
ADVECTING INTO OUR AREA OVERNIGHT INTO THURSDAY. THIS WILL BE AHEAD
OF A COLD FRONT PUSHING EASTWARD INTO THE CENTRAL PLAINS.
PRECIPITABLE WATER VALUES INCREASE INTO THE 1.5 TO 1.7IN RANGE. WITH
THIS IN MIND THERE WILL BE THE POTENTIAL WILL BE THERE FOR SOME
HEAVY RAINFALL. HAVE ISSUED A FLASH FLOOD WATCH FOR PORTIONS OF THE
AREA THIS EVENING THROUGH THURSDAY TO COVER THIS. SEE THE HYDROLOGY
SECTION BELOW FOR FURTHER DETAILS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 308 PM CDT WED MAY 29 2013
MAIN AXIS OF MOISTURE TRANSPORT/ENHANCED PRECIPITABLE WATER SHIFTS
EAST OF THE AREA THURSDAY NIGHT WITH A COLD FRONT LAGGING ACROSS
CENTRAL MN INTO EASTERN NEBRASKA/CENTRAL KS. SO...EXPECTING HEAVIER
RAINFALL TO TAPER OFF IN THE EVENING/OVERNIGHT FROM WEST TO EAST.
THE COLD FRONT WILL CONTINUE TO PUSH SLOWLY EAST INTO THE AREA
FRIDAY WITH INCREASING MOISTURE TRANSPORT INTO FAR SOUTHERN WI
DURING THE AFTERNOON. HAVE TAILORED SHRA/TS CHANCES WITH LIKELY
ACROSS THE SOUTH...TAPERING TO 40-50 POPS ACROSS THE NORTHWEST.
FOR FRIDAY NIGHT THROUGH SUNDAY...LOOK FOR A MID-LEVEL CLOSED LOW TO
MAKE ITS WAY ACROSS THE AREA FOR SCATTERED SHOWERS AND COOLING
TEMPERATURES.
SUNDAY NIGHT THROUGH MONDAY LOOKS DRY AND COOL AS A RIDGE OF HIGH
PRESSURE BUILDS IN FROM THE PLAINS.
SHOWER/THUNDERSTORM CHANCES RETURN TO THE AREA MONDAY NIGHT THROUGH
WEDNESDAY AS ANOTHER CLOSED MID-LEVEL LOW SYSTEM DROPS ACROSS THE
NORTHERN PLAINS INTO THE UPPER MISSISSIPPI RIVER REGION. THIS SYSTEM
WILL ALSO RESULT IN BELOW NORMAL TEMPERATURES THROUGH THIS PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED
AT 1233 PM CDT WED MAY 29 2013
THE WARM FRONT HAS PUSHED NORTH OF THE TAF SITES...WITH A WARM...
MOIST AND UNSTABLE AIRMASS OVERSPREADING SOUTHERN MN/WESTERN WI.
CLOUDS ALONG/SOUTH OF THE FRONT HAVE GENERALLY CLEARED OUT/BECOME
SCATTERED WITH THE MAIN FOCUS FOR SHRA/TSRA REMAINING WEST OF THE
AREA EARLY THIS AFTERNOON...PROVIDING A PERIOD OF IMPROVED VFR
CONDITIONS THRU MID TO LATE AFTERNOON.
MAIN FORCING/LIFT AND DEEPER MOISTURE CONTINUE TO SPREAD NORTHEAST
AND EAST ACROSS THE AREA LATER THIS AFTERNOON THRU TONIGHT INTO
THURSDAY. SHRA/TSRA CHANCES/TIMING IN THE SUMMERY AIRMASS OVER-
SPREADING THE AREA REMAIN PROBLEMATIC AFTER THE 20-23Z TIME-FRAME
THIS AFTERNOON THRU THU. APPEARS ONE ROUND OF SHRA/TSRA TO MOVE
ACROSS THE TAF SITES IN THE 20-03Z TIME PERIOD LATER TODAY.
CONFIDENCE MODERATE ON THIS ROUND. ANOTHER ROUND OF SHRA/TSRA LOOKS
TO MOVE ACROSS THE TAF SITES LATER TONIGHT/THU MORNING. GIVEN A WIDE
VARIETY OF SMALL SCALE TRIGGERS AND MODEL SOLUTIONS...CONFIDENCE
LOWER LATER TONIGHT/THU. OPTED NOT TO SPREAD EXTENSIVE PERIODS OF
TSRA/CB IN THE TAFS FOR NOW GIVEN MDT CONFIDENCE AT BEST. WILL JUST
HAVE TO PLAN ON SOME AMD/UPDATES ONCE TIMING/COVERAGE OF THE ROUNDS
OF CONVECTION BECOME CLEARER.
&&
.HYDROLOGY...TONIGHT THROUGH FRIDAY
ISSUED AT 1233 PM CDT WED MAY 29 2013
PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED ACROSS MUCH OF THE
REGION THROUGH FRIDAY. THE HEAVIEST RAIN IS EXPECTED TO FALL FROM
THURSDAY INTO FRIDAY. TOTAL RAINFALL FROM TODAY THROUGH FRIDAY
COULD RANGE FROM 1 TO 3 INCHES WITH LOCALLY HIGHER AMOUNTS
POSSIBLE. THIS COULD LEAD TO FLASH FLOODING AS WELL AS RISES AND
POSSIBLE FLOODING ON AREA RIVERS. A FLASH FLOOD WATCH HAS BEEN
ISSUED FOR A PORTION OF NORTHEAST IA/SOUTHEAST MN FOR TONIGHT/THU.
THIS IS LIKELY TO BE EXPANDED WITH LATER FORECAST ISSUANCES AS
DETAILS OF TIMING/LOCATION OF THE CONTINUED HEAVY RAIN THREAT
BECOME CLEARER. PORTIONS OF ANY ADDITIONAL WATCH MAY NEED TO GO
INTO THU EVENING...ESPECIALLY IN THE WI PORTION OF THE FCST AREA.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...FLASH FLOOD WATCH FROM 7 PM CDT THIS EVENING THROUGH THURSDAY
EVENING FOR MNZ094-095.
IA...FLASH FLOOD WATCH FROM 7 PM CDT THIS EVENING THROUGH
THURSDAY EVENING FOR IAZ008>010-018-019-029.
&&
$$
SHORT TERM...DAS
LONG TERM....DAS
AVIATION.....RRS
HYDROLOGY....DAS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1233 PM CDT WED MAY 29 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 356 AM CDT WED MAY 29 2013
LATEST WATER VAPOR IMAGERY CONTINUED TO SHOW A MESSY PATTERN ACROSS
THE CONUS. A LEADING SHORTWAVE...RESPONSIBLE FOR BRINGING SOME
SCATTERED RAIN SHOWERS TO THE AREA YESTERDAY...WAS MOVING ACROSS
NORTHERN LOWER MICHIGAN/EASTERN UPPER MICHIGAN. TWO MAIN SHORTWAVES
NOTED...ONE MOVING THROUGH WESTERN NEBRASKA AND ANOTHER MOVING
ACROSS NORTHERN TEXAS/WESTERN OKLAHOMA. A TROUGH WAS DIGGING INTO
THE CENTRAL ROCKIES/FOUR CORNERS REGION...ATTEMPTING TO EDGE EAST
INTO THE HIGH PLAINS. SURFACE OBSERVATIONS INDICATED A WARM FRONT
EXTENDING FROM SOUTHERN NEBRASKA NORTHEAST THROUGH SOUTHERN IOWA
INTO NORTHERN ILLINOIS.
THE WARM FRONT IS EXPECTED TO LIFT NORTH TODAY AS THE TROUGH EJECTS
NORTHEAST ACROSS THE CENTRAL PLAINS. SHOWERS AND THUNDERSTORMS ARE
EXPECTED TO DEVELOP ALONG THE FRONT AS IT PUSHES NORTHWARD AND A
SHORTWAVE LIFTS NORTH ACROSS THE UPPER MISSISSIPPI RIVER VALLEY.
THERE IS SOME UNCERTAINTY REGARDING HOW MUCH INSTABILITY BUILDS
ALONG THE FRONT. THE NAM SUGGESTS 0-3 KM MUCAPE VALUES CLIMB INTO
THE 1500 TO 2000 J/KG RANGE THIS AFTERNOON AS WARM...MOIST AIR
SURGES NORTHWARD. THIS SEEMS A BIT AGGRESSIVE GIVEN THE ABUNDANT
CLOUD COVER IN PLACE. ALSO...THE NAM SURFACE DEWPOINTS CLIMB TO
AROUND 70. THE RUC SURFACE DEWPOINTS ARE ALSO WAY TOO HIGH
TODAY...WITH DEWPOINTS CLIMBING INTO THE MID 70S. LOWER TO MID 60S
DEW POINTS ARE MUCH MORE REALISTIC...SO THINKING SURFACE BASED
CAPE VALUES OF AROUND 1000 J/KG IS NOT OUT OF THE QUESTION...BUT
WITH ONLY WEAK 0-6 KM SHEAR. CANNOT RULE OUT AN ISOLATED SEVERE
STORM BUT OVERALL PROBABILITIES APPEAR LOW AT LEAST THROUGH MID
AFTERNOON. WILL HAVE TO KEEP A VERY CLOSE WATCH ON AREAS WEST OF
THE MISSISSIPPI RIVER WHEN THE LOW LEVEL JET INTENSIFIES THIS
EVENING AND 0-1KM SHEAR RAMPS UP. IF STORMS ARE SURFACE BASED OVER
THESE AREAS EARLY THIS EVENING...CANNOT RULE OUT AN ISOLATED
TORNADO MAINLY WEST OF A LAKE CITY...TO HARMONY TO OELWEIN LINE.
WARMER AIR ALOFT MOVES IN...CENTERED AROUND 850 MB...AND SHOULD
EFFECTIVELY CAP THE ATMOSPHERE FOR FURTHER CONVECTIVE DEVELOPMENT
AT LEAST UNTIL 850 MB MOISTURE TRANSPORT KICKS IN LATE THIS
EVENING. SHEAR IS RATHER WEAK...UNTIL THE LOW LEVEL JET GETS GOING
THIS EVENING AND FOCUSES INTO EASTERN SOUTH DAKOTA/SOUTHWEST
MINNESOTA. PLAN ON TEMPERATURES GRADUALLY WARMING THROUGH THE DAY
AS THE FRONT MOVES THROUGH WITH HIGHS TOPPING OUT IN THE UPPER
70S. A FEW LOWER TO MID 80S ARE POSSIBLE OVER PORTIONS OF
NORTHEAST IOWA AND FAR SOUTHWEST WISCONSIN. THE WARM FRONT IS
EXPECTED TO PUSH INTO FAR NORTHERN WISCONSIN THIS EVENING. 850 MB
MOISTURE TRANSPORT IS INITIALLY FOCUSES WEST OF THE FORECAST AREA
EARLY IN THE EVENING BUT THEN SHIFT EAST INTO THE AREA LATE
TONIGHT INTO EARLY THURSDAY MORNING. WILL HAVE TO KEEP A VERY
CLOSE WATCH ON HOW THIS MOISTURE TRANSPORT EVOLVES
TONIGHT...ESPECIALLY ALONG AND WEST OF THE MISSISSIPPI RIVER. AT
THIS TIME...THINKING SHOWERS AND STORMS WILL PUSH INTO AREAS WEST
OF MISSISSIPPI RIVER BEFORE SUNRISE ON THURSDAY.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 356 AM CDT WED MAY 29 2013
ACTIVE SOUTHWEST FLOW ALOFT ACROSS THE FORECAST AREA WILL PRODUCE
WIDESPREAD SHOWERS AND THUNDERSTORMS ON THURSDAY. SEVERAL EMBEDDED
SHORTWAVES WILL MOVE OVER THE REGION THROUGH THE DAY WITH BROAD
MOISTURE TRANSPORT AND LIFT OVER THE REGION. A STRONGER WAVE MOVES
IN LATE THURSDAY AFTERNOON INTO THURSDAY EVENING...WITH SHOWERS
AND STORM PERSISTING. INSTABILITY IS NOT ALL THAT
IMPRESSIVE...GENERALLY IN THE 500 TO 1000 J/KG RANGE. 0-6 KM SHEAR
LOOKS TO HOVER IN THE 30 TO 40 KT RANGE SO CANNOT RULE OUT A FEW
STRONG TO SEVERE THUNDERSTORMS WITH HEAVY RAINFALL...LARGE HAIL
AND DAMAGING WINDS. THE REPEATED ROUND OF SHOWERS AND STORMS OVER
THE AREA WILL INCREASE FLOODING CONCERNS...ESPECIALLY OVER
NORTHEAST IOWA...SOUTHEAST MINNESOTA AND FAR WESTERN WISCONSIN.
RAINFALL AMOUNTS OF 1 TO 2 INCHES ARE POSSIBLE BY THURSDAY NIGHT.
THE TROUGH FINALLY CLOSES INTO AN UPPER LOW OVER WESTERN NORTH
DAKOTA. DESPITE THE WIDESPREAD SHOWERS AND STORMS ACROSS THE AREA
ON THURSDAY...THE WARM SOUTHERLY FLOW WILL ALLOW HIGH TEMPERATURES
TO WARM INTO THE MID TO UPPER 70S. THE UPPER LOW STARTS TO DRIFT
SOUTHEAST LATE THURSDAY NIGHT INTO FRIDAY AS A VIGOROUS SHORTWAVE
PUSHES THROUGH THE PLAINS AND LIFTS NORTHEAST INTO THE UPPER AND
MID MISSISSIPPI RIVER VALLEY. AS THIS WAVE MOVES IN ON FRIDAY 0-6
KM BULK SHEAR REALLY RAMPS UP FRIDAY AFTERNOON...45 TO 55 KTS
ACROSS MUCH OF THE FORECAST AREA. HOWEVER...A BOUNDARY PUSHES
ACROSS THE AREA LATE THURSDAY NIGHT INTO FRIDAY MORNING PUSHING
THE BEST INSTABILITY JUST SOUTHEAST OF THE FORECAST AREA..ACROSS
PORTIONS OF FAR EASTERN IOWA THROUGH NORTHERN ILLINOIS AND
SOUTHEAST WISCONSIN. CANNOT RULE OUT SEVERE STORMS ON FRIDAY BUT
THE HIGHER CHANCES LOOK TO BE SOUTHEAST OF THE AREA. PORTIONS OF
FAR NORTHEAST IOWA...AND EXTREME SOUTHWEST WISCONSIN COULD BE
IMPACTED. WILL HAVE TO KEEP A VERY CLOSE WATCH OVER THE NEXT FEW
FORECAST MODELS RUNS TO SEE EXACTLY WHERE THE BOUNDARY WILL SET
UP. SHOWER AND THUNDERSTORMS CHANCES CONTINUE INTO SATURDAY AS THE
UPPER LOW DRIFTS ACROSS WISCONSIN. RAIN CHANCES WILL CONTINUE INTO
SUNDAY AS A TROUGH REMAINS OVER THE GREAT LAKES REGION. AN
UNSEASONABLY COLD AIRMASS MOVES INTO THE REGION SUNDAY INTO MONDAY
WITH STANDARDIZED 850 MB TEMPERATURE ANOMALIES OF -1.5. WOULD
EXPECT OVERNIGHT LOWS ON SUNDAY TO FALL INTO THE UPPER 30S OVER
FAR NORTHERN WISCONSIN...FALLING INTO THE LOWER 40S ACROSS CENTRAL
WISCONSIN AND THE UPPER 40S ACROSS NORTHEAST IOWA. LOCATIONS ALONG
AND NORTH OF THE INTERSTATE 94 CORRIDOR COULD SEE SOME AREAS OF
FROST. HIGH PRESSURE SLIDES EAST OF THE REGION LATE MONDAY NIGHT
INTO TUESDAY AS A TROUGH PUSHES THROUGH THE NORTHERN PLAINS. A
WARM FRONT LOOKS TO LIFT INTO THE UPPER MISSISSIPPI RIVER VALLEY
LATE MONDAY NIGHT INTO TUESDAY BRINGING A CHANCE OF SHOWERS AND
THUNDERSTORMS TO THE AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED
AT 1233 PM CDT WED MAY 29 2013
THE WARM FRONT HAS PUSHED NORTH OF THE TAF SITES...WITH A WARM...
MOIST AND UNSTABLE AIRMASS OVERSPREADING SOUTHERN MN/WESTERN WI.
CLOUDS ALONG/SOUTH OF THE FRONT HAVE GENERALLY CLEARED OUT/BECOME
SCATTERED WITH THE MAIN FOCUS FOR SHRA/TSRA REMAINING WEST OF THE
AREA EARLY THIS AFTERNOON...PROVIDING A PERIOD OF IMPROVED VFR
CONDITIONS THRU MID TO LATE AFTERNOON.
MAIN FORCING/LIFT AND DEEPER MOISTURE CONTINUE TO SPREAD NORTHEAST
AND EAST ACROSS THE AREA LATER THIS AFTERNOON THRU TONIGHT INTO
THURSDAY. SHRA/TSRA CHANCES/TIMING IN THE SUMMERY AIRMASS OVER-
SPREADING THE AREA REMAIN PROBLEMATIC AFTER THE 20-23Z TIME-FRAME
THIS AFTERNOON THRU THU. APPEARS ONE ROUND OF SHRA/TSRA TO MOVE
ACROSS THE TAF SITES IN THE 20-03Z TIME PERIOD LATER TODAY.
CONFIDENCE MODERATE ON THIS ROUND. ANOTHER ROUND OF SHRA/TSRA LOOKS
TO MOVE ACROSS THE TAF SITES LATER TONIGHT/THU MORNING. GIVEN A WIDE
VARIETY OF SMALL SCALE TRIGGERS AND MODEL SOLUTIONS...CONFIDENCE
LOWER LATER TONIGHT/THU. OPTED NOT TO SPREAD EXTENSIVE PERIODS OF
TSRA/CB IN THE TAFS FOR NOW GIVEN MDT CONFIDENCE AT BEST. WILL JUST
HAVE TO PLAN ON SOME AMD/UPDATES ONCE TIMING/COVERAGE OF THE ROUNDS
OF CONVECTION BECOME CLEARER.
&&
.HYDROLOGY...TODAY THROUGH FRIDAY
ISSUED AT 1233 PM CDT WED MAY 29 2013
PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED ACROSS MUCH OF THE
REGION THROUGH FRIDAY. THE HEAVIEST RAIN IS EXPECTED TO FALL FROM
THURSDAY INTO FRIDAY. TOTAL RAINFALL FROM TODAY THROUGH FRIDAY
COULD RANGE FROM 1 TO 3 INCHES WITH LOCALLY HIGHER AMOUNTS
POSSIBLE. THIS COULD LEAD TO FLASH FLOODING AS WELL AS RISES AND
POSSIBLE FLOODING ON AREA RIVERS. A FLASH FLOOD WATCH HAS BEEN
ISSUED FOR A PORTION OF NORTHEAST IA/SOUTHEAST MN FOR TONIGHT/THU.
THIS IS LIKELY TO BE EXPANDED WITH LATER FORECAST ISSUANCES AS
DETAILS OF TIMING/LOCATION OF THE CONTINUED HEAVY RAIN THREAT
BECOME CLEARER. PORTIONS OF ANY ADDITIONAL WATCH MAY NEED TO GO
INTO THU EVENING...ESPECIALLY IN THE WI PORTION OF THE FCST AREA.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...FLASH FLOOD WATCH FROM 7 PM CDT THIS EVENING THROUGH THURSDAY
EVENING FOR MNZ094-095.
IA...FLASH FLOOD WATCH FROM 7 PM CDT THIS EVENING THROUGH THURSDAY
EVENING FOR IAZ008>010-018-019-029.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM....WETENKAMP
AVIATION.....RRS
HYDROLOGY....WETENKAMP/RRS