Forecast Discussions mentioning any of
"HRRR" "RR" "RUC13" "RUC" received at GSD on 04/24/12
AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
920 AM PDT SUN APR 22 2012
.SHORT TERM DISCUSSION...
STRONG UPPER RIDGE OVER THE AREA WILL SHIFT EAST OVER THE GREAT
BASIN TODAY AND OVER THE ROCKIES ON MONDAY. THIS WILL PROVIDE ONE
MORE DAY OF MUCH ABOVE NORMAL TEMPERATURES FOR NORTH CENTRAL
CALIFORNIA. CLEAR SKIES PREVAIL OVER ALL OF THE AREA THIS MORNING.
TEMPERATURES WERE IN THE MID TO UPPER 70`S AT MOST VALLEY
LOCATIONS...WHICH IS SLIGHTLY WARMER COMPARED TO YESTERDAY AT
THIS TIME. TEMPERATURE FORECAST CHALLENGE FOR TODAY CENTERS AROUND
TIMING OF DELTA BREEZE AND ITS IMPACT ON AFTERNOON HIGH
TEMPERATURES. HRRR AND WRF BRING DELTA BREEZE INTO THE CENTRAL
VALLEY AROUND 4 PM. CURRENT FORECAST HAS MOST VALLEY AREAS
REACHING NEAR 90 DEGS WHICH IS SLIGHTLY COOLER THAN YESTERDAYS
HIGH TEMPERATURES...ALTHOUGH WE ARE RUNNING WARMER VERSUS
YESTERDAY AT THIS TIME. MAY NEED TO ADD A FEW DEGREES TO CURRENT
FORECASTED HIGH TEMPS IF THIS TREND CONTINUES THIS MORNING.
SECOND CHALLENGE WILL BE CONVECTION THIS AFTERNOON INTO EARLY THIS
COMING WEEK. NOT MUCH IN THE WAY OF CONVECTION DEVELOPED YESTERDAY
AND WHAT LITTLE THERE WAS OCCURRED ON THE EAST SIDE OF THE SIERRA.
FEEL CONDITIONS ARE VERY SIMILAR TODAY...NAM SHOWS CONVECTION OVER
THE SRN SIERRA...WRF IS CONVECTION FREE OVER THE SIERRA BUT HAS
SOME ACTIVITY OVER THE COASTAL RANGE AND SHASTA COUNTY...HRRR IS
CONVECTION FREE OVER ALL OF THE CWA. THE WRF DOES SHOW SOME
INCREASE IN ACTIVITY OVER THE COASTAL RANGE COMPARED TO YESTERDAYS
RUNS AND CURRENT FORECAST REFLECTS THIS THINKING. BETTER PRECIP
CHANCES FOR MONDAY AS WEAK SHORT WAVE IN INCREASING SOUTHWEST FLOW
WILL ACT TO TRIGGER ACTIVITY OVER THE SIERRA.
.EXTENDED DISCUSSION (THURSDAY THROUGH SUNDAY)
THERE IS INCREASING CONFIDENCE IN A WET EVENT FOR WEDNESDAY NIGHT
AND THURSDAY. THERE IS ALSO BETTER TIMING FOR A CUTOFF UPPER LOW
OFF OF THE COAST OF SOUTHERN CALIFORNIA MOVING INLAND LATE
WEDNESDAY. THIS IS FOLLOWED BY A STRONGER ELONGATED LOW TO THE
NORTH EXTENDING INLAND AND PHASING WITH THE FIRST LOW ON THURSDAY.
PW LEVELS INITIALLY WILL BE OVER AN INCH AND THEN DROP OFF THROUGH
THE EVENT. DYNAMIC LIFT WILL BE ENHANCED WITH THE AREA BEING IN
THE EXIT REGION OF A 110 KT JET. SNOW LEVELS WILL INITIALLY BE
OVER 8000 FEET THEN DROPPING TO AROUND 6000 FEET BY THURSDAY
AFTERNOON. SNOW LEVELS WILL FALL FURTHER OVERNIGHT THURSDAY BUT
PRECIPITATION SHOULD BE WINDING DOWN BY EARLY FRIDAY MORNING. IT
IS TOO FAR OUT FOR A PRECISE ESTIMATE OF THE TOTAL QPF AT THIS
POINT BUT AN INCH OR TWO OF LIQUID EQUIVALENT IN THE MOUNTAINS
SEEMS REASONABLE.
TEMPERATURES WILL BE UNSEASONABLY COOL ON THURSDAY AND MAY NOT
EXCEED THE LOWER 60S IN SOME VALLEY LOCATIONS. FRIDAY SHOULD WARM
TO JUST A LITTLE BELOW NORMAL WITH LINGERING SHOWERS...MAINLY IN THE
MOUNTAINS. DRIER AND WARMING WEATHER IS EXPECTED NEXT WEEKEND AS
PACIFIC RIDGING EXTENDS EASTWARD. EK
&&
.AVIATION...
GENERALLY VFR CONDITIONS EXPECTED THROUGH SUNDAY AS HIGH PRESSURE
SHIFTS SLOWLY TO THE EAST SUNDAY. SCATTERED CUMULUS ARE POSSIBLE
OVER THE MOUNTAINS SUNDAY AFTERNOON WITH ISOLATED THUNDERSTORMS
POSSIBLE OVER THE COASTAL RANGE AND SHASTA COUNTY MOUNTAINS. WINDS
SHOULD BE GENERALLY LIGHT EXCEPT FOR SOUTHWEST WINDS OVER THE
DELTA INCREASING IN THE AFTERNOON WITH GUSTS TO AROUND 30 KT.
EK/DANG
&&
.STO WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS ALBANY NY
350 PM EDT SUN APR 22 2012
.SYNOPSIS...
A STRENGTHENING LOW PRESSURE CENTER WILL TRACK ACROSS THE REGION
TONIGHT. A PERIOD OF MODERATE TO HEAVY RAINFALL WILL ACCOMPANY
THIS STORM TONIGHT ACCOMPANIED BY STRONG WINDS ACROSS THE HIGHER
TERRAIN. IN THE WAKE OF THIS STORM...A COOL AND UNSETTLED WEATHER
PATTERN TO REMAIN FOR THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
LOW PRESSURE CENTER WAS OVER THE OUTER BANKS OF NORTH CAROLINA
WITH A CURRENT MSLP OF 995MB. 3HR ISALLOBARIC FALLS OF 6MBS WAS
ANALYZED JUST OFFSHORE OF KNTU WITH A CONTINUED ACTIVE COASTAL
FRONT OVER THE GULF STREAM. IR SATELLITE REPRESENTATION DOES
SUGGEST A BAROCLINIC LEAF WAS EVOLVING AS THE CENTER OF THE UPPER
LOW WAS EXITING THE NORTHERN FLORIDA COAST.
NCEP MODEL SUITE AN INTERNATIONAL GUIDANCE HAVE FINALLY COME INTO
AGREEMENT THAT THE SURFACE LOW WILL TRACK ALONG THE MID ATLANTIC
COAST THEN INLAND ACROSS NJ/PA/NY LATE TONIGHT. IMPRESSIVE THETA-E
ADVECTION /TROWAL/ AND 2-D FGEN WILL TRANSVERSE THE CWA TONIGHT
WITH FORECAST PWATS OF 2-3 STANDARD DEVIATIONS ABOVE NORMAL PER MID
APRIL CLIMATOLOGY. UPSLOPE ENHANCEMENTS ACROSS THE CATSKILLS AND
OUR ADJACENT WESTERN NEW ENGLAND COUNTIES WILL ADD TO THE RAINFALL
FORECAST WITH A GENERAL 1-3 INCHES AND ISOLATED 4 INCH AMOUNTS
STILL EXPECTED. THIS WILL BE ON TOP OF NEARLY 1 INCH OF RAIN THAT
OCCURRED LAST NIGHT WITH EMBEDDED CONVECTIVE ELEMENTS. SO WE WILL
CONTINUE WITH THE FLOOD WATCH FOR THOSE PREDETERMINED COUNTIES
/SEE HYDRO SECTION FOR FURTHER DETAILS/.
WIND POTENTIAL WAS CLOSELY EVALUATED AND COLLABORATED TODAY. THE
FORECAST 925-850MB WINDS AND TRAJECTORIES ARE PROGGED TO BE
BETWEEN 40-50KTS WITH EVEN HIGHER VALUES PER THE HIRES HRRR AND
BUFR PROFILES. IT APPEARS THE HIGHER MAGNITUDES ARE AT ELEVATIONS
AT AND ABOVE 1500 FEET WHERE WE WILL PLACE WIND ADVISORIES AT THIS
TIME.
THE SHOWALTER VALUES LOWERING CLOSE TO 0C OVER PORTIONS OF THE
BERKSHIRES...AND NW CT...AS THE H850-700 FRONTOGENESIS INTENSIFIES
AHEAD OF THE POTENT WAVE. THERE COULD BE A RUMBLE OF THUNDER
AROUND...BUT WE DID NOT INCLUDE IN THE GRIDDED FORECASTS AT THIS
TIME.
AS FOR TEMPERATURES...WE WILL HOLD TEMPERATURES NEARLY STEADY
OVERNIGHT WITH MOST AREAS REMAINING ABOVE FREEZING. THERE COULD BE
A LITTLE SNOW FOR THE HIGHEST TERRAIN OF THE DACKS LATE TONIGHT AS
AGEOSTROPHIC FLOW INCREASES IN THE LOW LEVELS BUT NOT EXPECTING
TOO MUCH ACCUMULATIONS...LESS THAN 1 INCH.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
MONDAY...THE DEEP AND INTENSE SFC CYCLONE GETS CAPTURED BY THE
CLOSED 500MB LOW OVER PENNSYLVANIA BY DAYBREAK. THE STORM GETS STEERED
SOUTHWEST OF THE REGION...WITH THE DRY SLOT QUICKLY BLASTING IN
FROM THE SOUTHEAST. THE DRY SLOT WILL SHUT DOWN THE MODERATE TO
HEAVY PRECIPITATION OVER MOST OF THE REGION. WE ACCOUNTED FOR THE
DRY SLOT WITH LOWER POPS IN THE AFTERNOON. THE POPS WERE REDUCED
TO SLIGHT AND LOW CHANCE VALUES FROM THE HUDSON RIVER VALLEY
EAST...WITH SLIGHTLY HIGHER POPS FOR THE FAVORED UPSLOPE REGIONS.
THE H850 TEMPS RISE TO +6C TO +8C EARLY ON....BUT COLDER AIR
WRAPS IN FROM THE SOUTH AND WEST DURING THE AFTERNOON. THE COLD
ADVECTION WILL LOWER TEMPS AT THAT LEVEL FROM -1C TO +3C FROM SOUTH
TO NORTH. HIGHS WILL BE IN THE 50S TO L60S ACROSS MOST OF THE
REGION...WITH SOME 40S OVER THE SRN DACKS...AND ERN CATSKILLS.
MONDAY NIGHT INTO TUESDAY...THE STORM BECOMES VERTICALLY STACKED
OVER W-CNTRL NY AND NRN PA. SPOKES OF SHORT-WAVE ENERGY WILL WRAP
AROUND THE STORM BRINGING SHOWERS TO THE REGION. THERE COULD BE
SOME SNOW SHOWERS OVER THE HIGHER TERRAIN WEST OF THE HUDSON RIVER
VALLEY MONDAY NIGHT...THOUGH THE HEAVIEST SNOW CHANCES WILL BE
WELL WEST OF THE REGION OVER WRN NY AND PERHAPS DOWNWIND OF LAKE
ONTARIO. MINOR LAKE ENHANCEMENT AS DELTA T/S INCREASE TO GREATER
THAN 13C WITH FAVORABLE WESTERLY FLOW IN THE BOUNDARY LAYER AND
CYCLONIC FLOW ALOFT. AT THIS TIME...WE WILL PLACE LIGHT
ACCUMULATIONS OF SNOW ACROSS NORTHERN HERKIMER AND HAMILTON
COUNTIES. LOWS MONDAY NIGHT WILL BE IN THE U30S TO L40S IN THE
VALLEYS...AND 30S OVER THE MTNS. THE CYCLONIC VORTICITY ADVECTION
ASSOCIATED WITH THE OCCLUDED SYSTEM WILL BRING A CHANCE OF SHOWERS
TO MOST OF THE REGION ON TUESDAY. THE MID LEVEL LAPSE RATES WILL
BE STEEP WITH H500 TEMPS CLOSE TO -26C. LIKELY POPS WERE UTILIZED
FOR THE WRN ZONES...WHERE THE BEST QG LIFT OCCURS WITH THE
DIFFERENTIAL CYCLONIC VORTICITY ADVECTION AND UPSLOPE ENHANCEMENTS...AS
THE CUTOFF SLOWLY MOVES NORTH OF THE BORDER. MAX TEMPS WILL RUN
ABOUT 5 TO 10 DEGREES BELOW NORMAL FOR LATE APRIL.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
HAVE GONE WITH AN HPC/ECMWF SOLUTION.
THE PERIOD LOOKS TO START OFF WITH A TROUGH OVER THE NORTHEASTERN
CONUS THIS TROUGH WILL HOLD TOUGH THROUGH MUCH OF THE PERIOD...BUT
LOOKS TO BEGIN TO LIFT OUT AT THE VERY END OF THE PERIOD.
A CLIPPER TYPE SYSTEM MIGHT BRING SOME ADDITIONAL LIGHTER
PRECIPITATION TO THE REGION THURSDAY. IF THIS SYSTEM WERE TRACK BIT
FURTHER NORTH (IMPLIED BY THE 12Z GFS) TEMPERATURES WOULD WARM...AT
LEAST IN OUR SOUTHERN AREAS AND THERE WOULD BE MIGHT EVEN BE A
THUNDER THREAT. HOWEVER...THE ECMWF AND HPC SOLUTION TRACKS THIS
SYSTEM MAINLY ACROSS SOUTHERN NEW YORK WHICH WOULD KEEP ALL OF OUR
REGION ON THE COOL SIDE OF THE SYSTEM. THIS IS THE SOLUTION WE WENT
FOR. IN FACT...TEMPERATURES COULD BE MARGINALLY COLD ENOUGH FOR SOME
SNOW TO MIX OVER THE NORTHERN MOUNTAINS DURING THE NIGHTTIME HOURS.
AS THIS STORM PULLS AWAY...THE ECMWF INDICATES ANOTHER UPPER LEVEL
CUTOFF LOW TO DUMBBELL DOWN FROM THE GREAT LAKES AND KEEP OUR
WEATHER SOMEWHAT UNSETTLED INTO FRIDAY AS MOVES ACROSS OUR REGION.
SOME SNOW SHOWERS ARE POSSIBLE ACROSS ANY OF THE HIGHER
TERRAIN..MAINLY EARLY AND LATE IN THE DAY.
SATURDAY LOOKS DRY BUT BRISK AS LOW PRESSURE AND ITS UPPER AIR LOW
SUPPORT SHOULD BE INTO THE CANADIAN MARITIMES.
BY SUNDAY...THE LATEST ECMWF HINTS OF ANOTHER DISTURBANCE AND ITS
WARM FRONT TO POSSIBLY BRING SOME PRECIPITATION TO MAINLY OUR
SOUTHERN AREAS. FOR NOW...JUST INTRODUCED SLIGHT CHANCES FOR SHOWERS
ON SUNDAY.
OVERALL...TEMPERATURES LOOK TO RUN ACTUALLY A LITTLE BELOW NORMAL
DURING THIS TIME FRAME. LOOK FOR HIGHS MAINLY IN THE 50S IN THE
VALLEYS EACH DAY...ONLY 40S ACROSS THE HIGHER TERRAIN. OVERNIGHT
LOWS WILL GENERALLY BE IN THE 30S...BUT DOWN INTO THE 20S ACROSS THE
HIGHER ELEVATION ON ALL BUT WED/THU OVERNIGHT.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
A STRENGTHENING LOW WILL HEAD NORTHWARD ALONG THE STALLED BOUNDARY UP
THE EASTERN SEABOARD THROUGH THIS EVENING. WHEN THE LOW REACHES THE
MID ATLANTIC REGION LATER THIS EVENING IT WILL BEGIN TO MOVE
NORTHWESTWARD AS ITS DRAWN IN UNDER THE UPPER LOW THAT WILL HAVE
DEVELOPED DURING THE DAY. THE SYSTEM WILL BECOME VERTICALLY STACKED
OVER CENTRAL PENNSYLVANIA OVERNIGHT. AS THE LOW APPROACHES A
WIDESPREAD RAIN WILL MOVE INTO THE REGION AND WILL COME DOWN HEAVY
AT TIMES ESPECIALLY FROM LATER THIS AFTERNOON THROUGH MUCH OF THE
OVERNIGHT PERIOD. WIDESPREAD MVFR CONDITIONS ARE EXPECTED TO PERSIST
TODAY AND AS THE HEAVIER RAIN MOVES IN IFR CONDITIONS WILL DEVELOP.
NORTH-NORTHEAST WINDS WILL INCREASE AND BECOME GUSTY TONIGHT. AT
KPOU HAVE LOW LEVEL WIND SHEAR BTWN 02Z AND 08Z AS THE STRONG LOW
LEVEL JET MOVES INTO REGION IN ADVANCE OF THE APPROACHING LOW.
.OUTLOOK...
MON...MVFR/IFR. RAIN SHOWERS IN THE MORNING BECOMING SCATTERED IN
THE AFTERNOON WITH CONDITIONS IMPROVING TO MVFR/VFR.
MON NIGHT-FRI...VFR/MVFR WITH CHANCE OF SHOWERS.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS THE NEXT SEVERAL DAYS WITH A SOAKING
MODERATE TO HEAVY RAINFALL TONIGHT.
COOL AND DAMP CONDITIONS WILL CONTINUE INTO THE MID WEEK PERIOD
&&
.HYDROLOGY...
THE LATEST DROUGHT MONITOR HAS OUR FORECAST AREA IN D0-D2. THE
WORST DROUGHT AREA IS OUR SOUTHERN MOST PORTION OF THE HYDRO
SERVICE AREA. ADDITIONAL MODERATE TO HEAVY RAINFALL IS ON THE
WAY...WHICH WILL ALLEVIATE THE DRY CONDITIONS OVER THE PAST
SEVERAL WEEKS. OUR LATEST QPF FORECAST IS BASED ON HPC WITH
OROGRAPHIC ENHANCEMENTS ADDED ALONG THE EAST FACING SLOPES OF THE
CATSKILLS...SRN GREENS...BERKSHIRES...AND LITCHFIELD HILLS. 1 TO 3
INCHES OF RAINFALL IS EXPECTED WITH SOME LOCALLY HIGHER AMOUNTS TO
4 INCHES.
PER THE LATEST NERFC FORECASTS...SEVERAL RIVER POINTS ACROSS OUR
ADJACENT WESTERN NEW ENGLAND COUNTIES ARE EXPECTED TO EXCEED MINOR
FLOOD STAGE. WE WILL CONTINUE TO MONITOR THE CATSKILLS AS SEVERAL
OF THESE RIVER POINTS WILL CLIMB BUT ARE EXPECTED TO REMAIN JUST
BELOW FLOOD STAGE AT THE PRESENT TIME. SO THE FLOOD WATCH FOR
PORTIONS OF THE CATSKILLS...MID HUDSON VALLEY...TACONICS AND
ADJACENT WESTERN NEW ENGLAND WILL REMAIN IN EFFECT OVERNIGHT.
OTHERWISE...ANTECEDENT CONDITIONS ARE VERY DRY...PRECIPITATION
DEFICITS ARE RUNNING 5 TO 10 INCHES BELOW NORMAL ACROSS EASTERN
NEW YORK AND WESTERN NEW ENGLAND. STREAMFLOW CONDITIONS ARE BELOW
NORMAL AND RESERVOIR LEVELS ACROSS THE AREA REMAIN NEAR TO
SLIGHTLY BELOW NORMAL. THE RESERVOIRS WILL PROVIDE STORAGE
CAPACITY FOR THE MAIN STEM RIVERS. THE FORECAST RAINFALL AMOUNTS
ARE EXPECTED TO PRODUCE SIGNIFICANT WITHIN BANK RISES WITH THE
POTENTIAL OF SOME VERY MINOR FLOODING ON A FEW ISOLATED MAIN STEM
RIVER POINTS.
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...FLOOD WATCH FROM 6 PM EDT THIS EVENING THROUGH MONDAY MORNING
FOR CTZ001-013.
NY...FLOOD WATCH FROM 6 PM EDT THIS EVENING THROUGH MONDAY MORNING
FOR NYZ043-047-053-054-058>061-063>066-084.
MA...FLOOD WATCH FROM 6 PM EDT THIS EVENING THROUGH MONDAY MORNING
FOR MAZ001-025.
VT...FLOOD WATCH FROM 6 PM EDT THIS EVENING THROUGH MONDAY MORNING
FOR VTZ013>015.
&&
$$
SYNOPSIS...BGM
NEAR TERM...BGM
SHORT TERM...BGM
LONG TERM...HWJIV
AVIATION...11
FIRE WEATHER...BGM
HYDROLOGY...BGM
FOR THE LATEST UPDATES...PLEASE VISIT OUR WEBPAGE AT
WWW.WEATHER.GOV/ALBANY
AREA FORECAST DISCUSSION...CORRECTED
NWS NEW YORK NY
1113 AM EDT SUN APR 22 2012
.SYNOPSIS...
A POTENT LOW PRESSURE SYSTEM APPROACHES CONTINUES TO STRENGTHEN
AND APPROACH FROM THE SOUTH THROUGH TONIGHT TO NORTHEAST
PENNSYLVANIA BY MONDAY MORNING...THEN TRACKS NORTHWEST INTO SOUTHEASTERN
ONTARIO BY TUESDAY MORNING. THIS LOW THEN SLOWLY DRIFTS INTO
QUEBEC AS IT WEAKENS INTO WEDNESDAY. ANOTHER STORM SYSTEM
APPROACHES FROM THE WEST WEDNESDAY NIGHT...THEN TRACKS JUST TO OUR
SOUTH ON THURSDAY...BEFORE HEADING TO THE CANADIAN MARITIMES BY
FRIDAY MORNING. HIGH PRESSURE THEN BUILDS IN TO CLOSE THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LOOKING AT WATER VAPOR IMAGERY...A STRONG NORTHERN STREAM
SHORTWAVE OVER THE LOWER OHIO VALLEY WAS RACING SE AND CATCHING UP
WITH A SOUTHERN STREAM SYSTEM OVER NORTHERN FLORIDA. THE
INTERACTION BETWEEN THESE TWO UPPER SYSTEMS WILL SERVE TO
STRENGTHEN AND DRAW NORTHWARD AN AREA OF SURFACE LOW PRESSURE OFF
THE CAROLINA COAST.
LIGHT RAIN...WELL AHEAD OF THIS SYSTEM IS BEGINNING TO WORK ITS
WAY INTO THE TRI-STATE. LATEST SREF AND HRRR SEEM TO HAVE A FAIRLY
GOOD HANDLE ON THIS...SO ADJUSTED POPS TODAY ACCORDINGLY. APPEARS
MODERATE-HEAVY RAINFALL WILL HOLD OFF TIL MID-LATE AFTERNOON WHEN
STRONGER FRONTOGENETIC AND Q-G FORCING BEGIN TO REACH THE REGION.
GIVEN CLOUD COVER AND DEVELOPING RAINFALL...DO NOT EXPECT
TEMPERATURES TO RISE MUCH MORE THAN 5 DEGREES OR SO FROM CURRENT
LEVELS. THIS IS ALSO CONSISTENT WITH A BLEND OF MAV/LAV/MET
GUIDANCE WITH NAM 2-METER TEMPERATURES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
CLOSED STACKED LOW TO THE WEST WILL SLOWLY MOVE NORTHWARD IN TIME.
THIS WILL ALLOW A DEEP SOUTHERLY FLOW TO PREVAIL. PLENTY OF WARM AIR
ADVECTION...AND ABUNDANT MOISTURE GETS TRANSPORTED NORTHWARD AND
WILL SET THE STAGE FOR QUITE A BIT OF RAIN TONIGHT ACROSS THE AREA.
MID LEVEL FRONTOGENESIS REMAINS TO THE NW OF THE AREA...BUT DEEP
SOUTHERLY FETCH AND THETA ADVECTION WILL ENSURE RAIN HEAVY AT TIMES
THROUGH MUCH OF THE NIGHT.
THE MODELS ARE IN GENERAL AGREEMENT OF STEERING THE SFC LOW ACROSS
NJ AND TO OUR WEST. PRESSURE GRADIENT TIGHTENS...AND NAM REMAINS ONE
OF THE DEEPER SOLUTIONS WITH REGARD TO THE SFC LOW INITIALLY. EAST
WINDS INCREASE...BUT DO NOT HAVE THE CONFIDENCE TO ISSUE ANY WIND
RELATED HEADLINES AT THIS TIME. MY BEST GUESS IS FOR A FEW REPORTS
CLOSE TO ADVISORY CRITERIA ACROSS PORTIONS OF LONG ISLAND AND
POSSIBLY COASTAL CT. HOWEVER...H8 JET STRENGTH NOT QUITE WHAT I WOULD
WANT IT TO BE FOR WIND ADVISORY LEVEL WINDS VERIFYING HERE...AND
THAT IS ACCORDING TO STRONGER NAM. GFS AND ECMWF ADVERTISE A MUCH
WEAKER JET LOCATED TO THE EAST.
LATEST 6Z NAM DOES FORECAST A 75 KT H8 JET OVER ERN LONG ISLAND AND
SE CT. THESE EASTERN LOCATIONS WILL NEED TO BE WATCHED.
THE MAIN ISSUE WILL BE RAINFALL AMOUNTS. LATEST PRECIPITATION RUN
ACCUMULATIONS FROM 00Z/06Z MODEL SUITE SUGGESTS SLIGHTLY LOWER
AMOUNTS FROM PREVIOUS RUNS. HOWEVER...STILL HAVE ENOUGH SUPPORT TO
CONTINUE THE FLOOD WATCH. AS MENTIONED...RAIN WILL TAPER OFF
MONDAY AS DRIER AIR ALOFT MOVES IN. THE BULK OF THE RAIN WILL BE
FROM THIS AFTERNOON INTO EARLY MONDAY MORNING...SO FLOOD WATCH
TIMING LOOKS GOOD. SEE THE HYDROLOGY SECTION FOR FURTHER
DETAILS.
TEMPS CLOSE TO MOS THROUGH THIS TIME FRAME...WITH SMALLER DIURNAL
DIFFERENCES NOTED DUE TO CLOUDS AND ONSHORE WINDS.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
UNSETTLED WEATHER REMAINS IN THE FORECAST FOR THE START OF THE LONG
TERM PERIOD. DEEP...ELONGATED UPPER TROUGH REMAINS ALONG THE EASTERN
SEABOARD AND WILL BE SLOW TO DEPART. NORTHERLY FLOW WILL USER A
RELATIVELY DRY AIR MASS TO THE REGION...HOWEVER...WITH WITH SEVERAL
STRONG SHORTWAVES ROTATING THROUGH THE REGION ASSOCIATED WITH THE
UPPER LOW...WILL KEEP AT LEAST A CHANCE FOR PRECIP IN THE FORECAST
THROUGH TUESDAY NIGHT. ENOUGH COLD AIR MAY GET WRAPPED INTO THE
REGION TUESDAY NIGHT TO ALLOW FOR SOME SNOW SHOWERS TO MIX WITH THE
RAIN ACROSS WESTERN PORTIONS OF ORANGE COUNTY.
A WEAK CLIPPER SYSTEM APPROACHES FROM THE WEST WEDNESDAY. WITH
TIMING UNCERTAINTIES AND TO KEEP FORECAST CONTINUITY HAVE KEPT
CHANCE POPS THROUGH WEDNESDAY...AND THEN BACK TO CHANCE LATE
WEDNESDAY INTO THURSDAY.
UPPER TROUGH MOVES TO THE EAST THURSDAY NIGHT INTO THE WEEKEND AS
RIDGE BUILDS TO THE WEST. SURFACE HIGH BUILDS FROM THE NORTH. DEEP
NORTHWEST FLOW ACROSS THE AREA LATE IN THE WEEK AND INTO THE
UPCOMING WEEKEND WILL KEEP TEMPERATURES COOL.
FOR WEDNESDAY THROUGH SATURDAY USED A BLEND OF THE GFS AND HPC
GUIDANCE.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
DEEPENING LOW PRES WILL TRACK ALONG THE EASTERN SEABOARD LATER
TODAY...PASSING JUST WEST OF THE NYC METRO AREA EARLY MON
MORNING...AND THEN MOVING INTO CENTRAL PA/NY LATER MON.
RAIN SHIELD NOW PAST NYC METRO AND WILL MOVE INLAND AND TO THE CT
COAST LATE THIS MORNING. EXPECT MAINLY VFR CONDS TO START...BUT
BAND OF MODERATE RAIN JUST OFF THE NJ COAST COULD BRING IFR
CONDITIONS TO KISP/KBDR EARLY THIS AFTERNOON.
IFR CONDITIONS SHOULD ENCOMPASS THE ENTIRE REGION BY LATE DAY...
WITH INCREASING E WINDS. HEAVY RAIN WILL MOVE IN AFTER DARK...
WITH IFR/LIFR CONDITIONS.
N WINDS AT OR JUST UNDER 10 KT THIS MORNING SHOULD VEER NE AND
INCREASE SLIGHTLY THIS AFTERNOON...THEN VEER MORE E-NE AND INCREASE
TO 15-20 KT WITH 20-30 KT GUSTS BY TONIGHT. WINDS WILL INCREASE
FURTHER THIS EVENING TO 20-30 KT WITH 30+ KT GUSTS. STRONG LOW
LEVEL JET WILL CAUSE LLWS LATER TONIGHT.
OUTLOOK FOR 12Z MON THROUGH THU...
.MON...WINDS DIMINISH AND SHIFT TO THE SE IN THE MORNING...THEN TO
THE SW AND INCREASE ONCE AGAIN TO 15-25 KT WITH 30-35 KT GUSTS.
CONDS IMPROVE TO VFR BY AFTERNOON.
.MON NIGHT-WED...VFR. GUSTY WINDS.
.WED NIGHT-THU...MVFR OR LOWER POSSIBLE.
&&
.MARINE...
MINOR CHANGES TO GRIDS THIS MORNING...WITH MAIN CHANGE TO DELAY
SLIGHTLY ONSET OF STRONGER WINDS PER LATEST TRENDS IN OBSERVATIONS
AND GUIDANCE.
NORTHERLY WINDS EARLY THIS MORNING WILL TURN TOWARD THE EAST AND
INCREASE THIS AFTERNOON AS LOW PRESSURE APPROACHES FROM THE SOUTH.
THIS LOW DEEPENS AS IT PASSES TO THE WEST OF THE WATERS TONIGHT.
EASTERLY GALES CAN BE EXPECTED TONIGHT. THESE WINDS THEN SHIFT TO
THE SOUTH BY MONDAY MORNING. THERE WILL BE A LULL IN THE WINDS AS
THE LOW NEARS THE WATERS LATE TONIGHT THROUGH MONDAY MORNING. THEN
SOUTHERLY WINDS INCREASE MONDAY AFTERNOON AND COULD APPROACH GALE
FORCE ONCE AGAIN BY LATE IN THE DAY. HOWEVER THE TIME BETWEEN GALE
FORCE WINDS TONIGHT AND LATE MONDAY IS TOO GREAT TO EXTEND THE GALE
WARNING AT THIS TIME.
SEAS WILL BUILD TODAY AND TONIGHT...WITH ROUGH CONDITIONS
ANTICIPATED THROUGH MONDAY.
STRONG SCA CONDITIONS...POSSIBLY APPROACHING GALES AT TIMES ON THE
OCEAN WATERS...WILL PERSIST THROUGH TUESDAY NIGHT...THEN CONDITIONS
GRADUALLY SUBSIDE TO SUB-SCA CRITERIA.
NORTHWEST WINDS BEHIND DEPARTING LOW THURSDAY NIGHT MAY AGAIN COME
UP TO SMALL CRAFT ACROSS THE WATERS...ESPECIALLY ON THE OCEAN.
&&
.HYDROLOGY...
HEAVY RAIN MOVES IN FROM THE SOUTH THIS AFTERNOON AND CONTINUES
TONIGHT BEFORE TAPERING OFF MONDAY. RAINFALL AMOUNTS SHOULD RANGE
FROM 2 TO 3.5 INCHES. LOCALLY HIGHER AMOUNTS CANNOT BE RULED OUT.
MAIN STEM RIVERS SHOULD NOT HAVE ANY PROBLEMS. EVEN 4 INCH AMOUNTS
KEEP RIVER LEVELS BELOW THEIR RESPECTIVE FLOOD STAGES.
HOWEVER...FLASHY SMALL STREAMS COULD FLOOD. SIGNIFICANT URBAN AND
POOR DRAINAGE FLOODING IS POSSIBLE. HARD DRY GROUND DUE TO LACK
OF RECENT RAINFALL...AND STORM DRAINS THAT HAVE NOT YET BEEN
CLEARED OF WINTER DEBRIS...MAY ACTUALLY CONTRIBUTE TO RUNOFF.
THIS RAIN WILL HELP ALLEVIATE THE MODERATE TO SEVERE DROUGHT
CONDITIONS.
MONDAY NIGHT AND TUESDAY...UP TO A TENTH OF AN INCH IN POSSIBLE IN
SCATTERED SHOWERS.
&&
.TIDES/COASTAL FLOODING...
WITH THE REGION AROUND A NEW MOON IN THE LUNAR CYCLE...AND STRONG
EASTERLY WINDS FORECAST LATE TODAY AND TONIGHT...IT APPEARS THAT
MINOR COASTAL FLOOD BENCHMARKS COULD BE REACHED ON WESTERN LONG
ISLAND SOUND AROUND THE TIME OF HIGH TIDE. HIGH TIDE OCCURS AFTER
MIDNIGHT TONIGHT. HOWEVER...LATEST COASTAL FLOODING GUIDANCE
INDICATES TIDE LEVELS FALL SHORT. MY FEELING IS THAT THIS GUIDANCE
IS UNDERDONE. HOWEVER...I DO NOT HAVE THE CONFIDENCE NEEDED TO ISSUE
A COASTAL FLOOD ADVISORY AT THIS TIME.
BECAUSE THE HIGH TIDE FOR NY HARBOR/SOUTH SHORE BAYS OF LONG
ISLAND/NYC OCCURS THIS EVENING...THE WINDS LIKELY WILL NOT BE
STRONG ENOUGH BY THEN TO ACHIEVE THE AROUND 1.5 FT DEPARTURES
NEEDED FOR MINOR COASTAL FLOODING.
FOR THE MONDAY MORNING/EARLY AFTERNOON HIGH TIDE CYCLE...THE WINDS
WILL BE INCREASING OUT OF THE SOUTH...AND THIS WILL HELP KEEP TIDAL
DEPARTURES UP IN THE SOUTH SHORE BAYS...WHILE ALLOWING TIDAL PILING
TO DISSIPATE IN THE SOUND AND HARBOR. AS A RESULT...CURRENTLY ONLY
SEE THE POTENTIAL FOR MINOR COASTAL FLOODING...IF ANY...IN THE SOUTH
SHORE BAYS OF NYC/NASSAU COUNTY ON MONDAY MORNING. TIDAL DEPARTURES
OF 2-2.5 ARE NEEDED TO REACH COASTAL FLOOD BENCHMARKS FOR THE MONDAY
MORNING HIGH TIDE.
HIGH SURF IS POSSIBLE ALONG THE BEACHES TONIGHT AS SEAS BECOME QUITE
ROUGH AND SWELLS INCREASE.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH THROUGH MONDAY MORNING FOR CTZ005>012.
NY...FLOOD WATCH THROUGH MONDAY MORNING FOR NYZ067>075-078>081-
176>179.
NJ...FLOOD WATCH THROUGH MONDAY MORNING FOR NJZ002-004-006-103>108.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ330-
335-338-340-345-350-353-355.
GALE WARNING FROM 6 PM THIS EVENING TO 6 AM EDT MONDAY FOR
ANZ330-335-338-340-345-350-353-355.
&&
$$
SYNOPSIS...MALOIT/MPS/PW
NEAR TERM...MALOIT
SHORT TERM...PW
LONG TERM...MPS
AVIATION...GOODMAN/MPS
MARINE...MALOIT/MPS/PW
HYDROLOGY...PW
TIDES/COASTAL FLOODING...PW
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1100 AM EDT SUN APR 22 2012
.SYNOPSIS...
A POTENT LOW PRESSURE SYSTEM APPROACHES CONTINUES TO STRENGTHEN
AND APPROACH FROM THE SOUTH THROUGH TONIGHT TO NORTHEAST
PENNSYLVANIA BY MONDAY MORNING...THEN TRACKS NORTHWEST INTO SOUTHEASTERN
ONTARIO BY TUESDAY MORNING. THIS LOW THEN SLOWLY DRIFTS INTO
QUEBEC AS IT WEAKENS INTO WEDNESDAY. ANOTHER STORM SYSTEM
APPROACHES FROM THE WEST WEDNESDAY NIGHT...THEN TRACKS JUST TO OUR
SOUTH ON THURSDAY...BEFORE HEADING TO THE CANADIAN MARITIMES BY
FRIDAY MORNING. HIGH PRESSURE THEN BUILDS IN TO CLOSE THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LOOKING AT WATER VAPOR IMAGERY...A STRONG NORTHERN STREAM
SHORTWAVE OVER THE LOWER OHIO VALLEY WAS RACING SE AND CATCHING UP
WITH A SOUTHERN STREAM SYSTEM OVER NORTHERN FLORIDA. THE
INTERACTION BETWEEN THESE TWO UPPER SYSTEMS WILL SERVE TO
STRENGTHEN AND DRAW NORTHWARD AN AREA OF SURFACE LOW PRESSURE OFF
THE CAROLINA COAST.
LIGHT RAIN...WELL AHEAD OF THIS SYSTEM IS BEGINNING TO WORK ITS
WAY INTO THE TRI-STATE. LATEST SREF AND HRRR SEEM TO HAVE A FAIRLY
GOOD HANDLE ON THIS...SO ADJUSTED POPS TODAY ACCORDINGLY. APPEARS
MODERATE-HEAVY RAINFALL WILL HOLD OFF TIL MID-LATE AFTERNOON WHEN
STRONGER FRONTOGENETIC AND Q-G FORCING BEGIN TO REACH THE REGION.
GIVEN CLOUD COVER AND DEVELOPING RAINFALL...DO NOT EXPECT
TEMPERATURES TO RISE MUCH MORE THAN 5 DEGREES OR SO FROM CURRENT
LEVELS. THIS IS ALSO CONSISTENT WITH A BLEND OF MAV/LAV/MET
GUIDANCE WITH NAM 2-METER TEMPERATURES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
CLOSED STACKED LOW TO THE WEST WILL SLOWLY MOVE NORTHWARD IN TIME.
THIS WILL ALLOW A DEEP SOUTHERLY FLOW TO PREVAIL. PLENTY OF WARM AIR
ADVECTION...AND ABUNDANT MOISTURE GETS TRANSPORTED NORTHWARD AND
WILL SET THE STAGE FOR QUITE A BIT OF RAIN TONIGHT ACROSS THE AREA.
MID LEVEL FRONTOGENESIS REMAINS TO THE NW OF THE AREA...BUT DEEP
SOUTHERLY FETCH AND THETA ADVECTION WILL ENSURE RAIN HEAVY AT TIMES
THROUGH MUCH OF THE NIGHT.
THE MODELS ARE IN GENERAL AGREEMENT OF STEERING THE SFC LOW ACROSS
NJ AND TO OUR WEST. PRESSURE GRADIENT TIGHTENS...AND NAM REMAINS ONE
OF THE DEEPER SOLUTIONS WITH REGARD TO THE SFC LOW INITIALLY. EAST
WINDS INCREASE...BUT DO NOT HAVE THE CONFIDENCE TO ISSUE ANY WIND
RELATED HEADLINES AT THIS TIME. MY BEST GUESS IS FOR A FEW REPORTS
CLOSE TO ADVISORY CRITERIA ACROSS PORTIONS OF LONG ISLAND AND
POSSIBLY COASTAL CT. HOWEVER...H8 JET STRENGTH NOT QUITE WHAT I WOULD
WANT IT TO BE FOR WIND ADVISORY LEVEL WINDS VERIFYING HERE...AND
THAT IS ACCORDING TO STRONGER NAM. GFS AND ECMWF ADVERTISE A MUCH
WEAKER JET LOCATED TO THE EAST.
LATEST 6Z NAM DOES FORECAST A 75 KT H8 JET OVER ERN LONG ISLAND AND
SE CT. THESE EASTERN LOCATIONS WILL NEED TO BE WATCHED.
THE MAIN ISSUE WILL BE RAINFALL AMOUNTS. LATEST PRECIPITATION RUN
ACCUMULATIONS FROM 00Z/06Z MODEL SUITE SUGGESTS SLIGHTLY LOWER
AMOUNTS FROM PREVIOUS RUNS. HOWEVER...STILL HAVE ENOUGH SUPPORT TO
CONTINUE THE FLASH FLOOD WATCH. SEE THE HYDROLOGY SECTION FOR
FURTHER DETAILS.
AS MENTIONED...RAIN WILL TAPER OFF MONDAY AS DRIER AIR ALOFT MOVES
IN. THE BULK OF THE RAIN WILL BE FROM THIS AFTERNOON INTO EARLY
MONDAY MORNING...SO FLOOD WATCH TIMING LOOKS GOOD.
TEMPS CLOSE TO MOS THROUGH THIS TIME FRAME...WITH SMALLER DIURNAL
DIFFERENCES NOTED DUE TO CLOUDS AND ONSHORE WINDS.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
UNSETTLED WEATHER REMAINS IN THE FORECAST FOR THE START OF THE LONG
TERM PERIOD. DEEP...ELONGATED UPPER TROUGH REMAINS ALONG THE EASTERN
SEABOARD AND WILL BE SLOW TO DEPART. NORTHERLY FLOW WILL USER A
RELATIVELY DRY AIR MASS TO THE REGION...HOWEVER...WITH WITH SEVERAL
STRONG SHORTWAVES ROTATING THROUGH THE REGION ASSOCIATED WITH THE
UPPER LOW...WILL KEEP AT LEAST A CHANCE FOR PRECIP IN THE FORECAST
THROUGH TUESDAY NIGHT. ENOUGH COLD AIR MAY GET WRAPPED INTO THE
REGION TUESDAY NIGHT TO ALLOW FOR SOME SNOW SHOWERS TO MIX WITH THE
RAIN ACROSS WESTERN PORTIONS OF ORANGE COUNTY.
A WEAK CLIPPER SYSTEM APPROACHES FROM THE WEST WEDNESDAY. WITH
TIMING UNCERTAINTIES AND TO KEEP FORECAST CONTINUITY HAVE KEPT
CHANCE POPS THROUGH WEDNESDAY...AND THEN BACK TO CHANCE LATE
WEDNESDAY INTO THURSDAY.
UPPER TROUGH MOVES TO THE EAST THURSDAY NIGHT INTO THE WEEKEND AS
RIDGE BUILDS TO THE WEST. SURFACE HIGH BUILDS FROM THE NORTH. DEEP
NORTHWEST FLOW ACROSS THE AREA LATE IN THE WEEK AND INTO THE
UPCOMING WEEKEND WILL KEEP TEMPERATURES COOL.
FOR WEDNESDAY THROUGH SATURDAY USED A BLEND OF THE GFS AND HPC
GUIDANCE.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
DEEPENING LOW PRES WILL TRACK ALONG THE EASTERN SEABOARD LATER
TODAY...PASSING JUST WEST OF THE NYC METRO AREA EARLY MON
MORNING...AND THEN MOVING INTO CENTRAL PA/NY LATER MON.
RAIN SHIELD NOW PAST NYC METRO AND WILL MOVE INLAND AND TO THE CT
COAST LATE THIS MORNING. EXPECT MAINLY VFR CONDS TO START...BUT
BAND OF MODERATE RAIN JUST OFF THE NJ COAST COULD BRING IFR
CONDITIONS TO KISP/KBDR EARLY THIS AFTERNOON.
IFR CONDITIONS SHOULD ENCOMPASS THE ENTIRE REGION BY LATE DAY...
WITH INCREASING E WINDS. HEAVY RAIN WILL MOVE IN AFTER DARK...
WITH IFR/LIFR CONDITIONS.
N WINDS AT OR JUST UNDER 10 KT THIS MORNING SHOULD VEER NE AND
INCREASE SLIGHTLY THIS AFTERNOON...THEN VEER MORE E-NE AND INCREASE
TO 15-20 KT WITH 20-30 KT GUSTS BY TONIGHT. WINDS WILL INCREASE
FURTHER THIS EVENING TO 20-30 KT WITH 30+ KT GUSTS. STRONG LOW
LEVEL JET WILL CAUSE LLWS LATER TONIGHT.
OUTLOOK FOR 12Z MON THROUGH THU...
.MON...WINDS DIMINISH AND SHIFT TO THE SE IN THE MORNING...THEN TO
THE SW AND INCREASE ONCE AGAIN TO 15-25 KT WITH 30-35 KT GUSTS.
CONDS IMPROVE TO VFR BY AFTERNOON.
.MON NIGHT-WED...VFR. GUSTY WINDS.
.WED NIGHT-THU...MVFR OR LOWER POSSIBLE.
&&
.MARINE...
MINOR CHANGES TO GRIDS THIS MORNING...WITH MAIN CHANGE TO DELAY
SLIGHTLY ONSET OF STRONGER WINDS PER LATEST TRENDS IN OBSERVATIONS
AND GUIDANCE.
NORTHERLY WINDS EARLY THIS MORNING WILL TURN TOWARD THE EAST AND
INCREASE THIS AFTERNOON AS LOW PRESSURE APPROACHES FROM THE SOUTH.
THIS LOW DEEPENS AS IT PASSES TO THE WEST OF THE WATERS TONIGHT.
EASTERLY GALES CAN BE EXPECTED TONIGHT. THESE WINDS THEN SHIFT TO
THE SOUTH BY MONDAY MORNING. THERE WILL BE A LULL IN THE WINDS AS
THE LOW NEARS THE WATERS LATE TONIGHT THROUGH MONDAY MORNING. THEN
SOUTHERLY WINDS INCREASE MONDAY AFTERNOON AND COULD APPROACH GALE
FORCE ONCE AGAIN BY LATE IN THE DAY. HOWEVER THE TIME BETWEEN GALE
FORCE WINDS TONIGHT AND LATE MONDAY IS TOO GREAT TO EXTEND THE GALE
WARNING AT THIS TIME.
SEAS WILL BUILD TODAY AND TONIGHT...WITH ROUGH CONDITIONS
ANTICIPATED THROUGH MONDAY.
STRONG SCA CONDITIONS...POSSIBLY APPROACHING GALES AT TIMES ON THE
OCEAN WATERS...WILL PERSIST THROUGH TUESDAY NIGHT...THEN CONDITIONS
GRADUALLY SUBSIDE TO SUB-SCA CRITERIA.
NORTHWEST WINDS BEHIND DEPARTING LOW THURSDAY NIGHT MAY AGAIN COME
UP TO SMALL CRAFT ACROSS THE WATERS...ESPECIALLY ON THE OCEAN.
&&
.HYDROLOGY...
HEAVY RAIN MOVES IN FROM THE SOUTH THIS AFTERNOON AND CONTINUES
TONIGHT BEFORE TAPERING OFF MONDAY. RAINFALL AMOUNTS SHOULD RANGE
FROM 2 TO 3.5 INCHES. LOCALLY HIGHER AMOUNTS CANNOT BE RULED OUT.
MAIN STEM RIVERS SHOULD NOT HAVE ANY PROBLEMS. EVEN 4 INCH AMOUNTS
KEEP RIVER LEVELS BELOW THEIR RESPECTIVE FLOOD STAGES.
HOWEVER...FLASHY SMALL STREAMS COULD FLOOD. SIGNIFICANT URBAN AND
POOR DRAINAGE FLOODING IS POSSIBLE. HARD DRY GROUND DUE TO LACK
OF RECENT RAINFALL...AND STORM DRAINS THAT HAVE NOT YET BEEN
CLEARED OF WINTER DEBRIS...MAY ACTUALLY CONTRIBUTE TO RUNOFF.
THIS RAIN WILL HELP ALLEVIATE THE MODERATE TO SEVERE DROUGHT
CONDITIONS.
MONDAY NIGHT AND TUESDAY...UP TO A TENTH OF AN INCH IN POSSIBLE IN
SCATTERED SHOWERS.
&&
.TIDES/COASTAL FLOODING...
WITH THE REGION AROUND A NEW MOON IN THE LUNAR CYCLE...AND STRONG
EASTERLY WINDS FORECAST LATE TODAY AND TONIGHT...IT APPEARS THAT
MINOR COASTAL FLOOD BENCHMARKS COULD BE REACHED ON WESTERN LONG
ISLAND SOUND AROUND THE TIME OF HIGH TIDE. HIGH TIDE OCCURS AFTER
MIDNIGHT TONIGHT. HOWEVER...LATEST COASTAL FLOODING GUIDANCE
INDICATES TIDE LEVELS FALL SHORT. MY FEELING IS THAT THIS GUIDANCE
IS UNDERDONE. HOWEVER...I DO NOT HAVE THE CONFIDENCE NEEDED TO ISSUE
A COASTAL FLOOD ADVISORY AT THIS TIME.
BECAUSE THE HIGH TIDE FOR NY HARBOR/SOUTH SHORE BAYS OF LONG
ISLAND/NYC OCCURS THIS EVENING...THE WINDS LIKELY WILL NOT BE
STRONG ENOUGH BY THEN TO ACHIEVE THE AROUND 1.5 FT DEPARTURES
NEEDED FOR MINOR COASTAL FLOODING.
FOR THE MONDAY MORNING/EARLY AFTERNOON HIGH TIDE CYCLE...THE WINDS
WILL BE INCREASING OUT OF THE SOUTH...AND THIS WILL HELP KEEP TIDAL
DEPARTURES UP IN THE SOUTH SHORE BAYS...WHILE ALLOWING TIDAL PILING
TO DISSIPATE IN THE SOUND AND HARBOR. AS A RESULT...CURRENTLY ONLY
SEE THE POTENTIAL FOR MINOR COASTAL FLOODING...IF ANY...IN THE SOUTH
SHORE BAYS OF NYC/NASSAU COUNTY ON MONDAY MORNING. TIDAL DEPARTURES
OF 2-2.5 ARE NEEDED TO REACH COASTAL FLOOD BENCHMARKS FOR THE MONDAY
MORNING HIGH TIDE.
HIGH SURF IS POSSIBLE ALONG THE BEACHES TONIGHT AS SEAS BECOME QUITE
ROUGH AND SWELLS INCREASE.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH THROUGH MONDAY MORNING FOR CTZ005>012.
NY...FLOOD WATCH THROUGH MONDAY MORNING FOR NYZ067>075-078>081-
176>179.
NJ...FLOOD WATCH THROUGH MONDAY MORNING FOR NJZ002-004-006-103>108.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ330-
335-338-340-345-350-353-355.
GALE WARNING FROM 6 PM THIS EVENING TO 6 AM EDT MONDAY FOR
ANZ330-335-338-340-345-350-353-355.
&&
$$
SYNOPSIS...MALOIT/MPS/PW
NEAR TERM...MALOIT
SHORT TERM...PW
LONG TERM...MPS
AVIATION...GOODMAN/MPS
MARINE...MALOIT/MPS/PW
HYDROLOGY...PW
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS ALBANY NY
149 AM EDT SUN APR 22 2012
.SYNOPSIS...
A COLD FRONT CONTINUES TO MOVE SOUTHEAST OF SOUTHERN NEW YORK AND
NEW ENGLAND THIS MORNING...AS A WAVE OF LOW PRESSURE MOVING ALONG IT
CONTINUES TO BRING THE FIRST WIDESPREAD MEASURABLE RAINFALL SINCE
APRIL FIRST. A BRIEF LULL IN THE RAIN WILL OCCUR SUNDAY MORNING. AN
INTENSIFYING AREA OF LOW PRESSURE WILL APPROACH FROM THE MID
ATLANTIC REGION SUNDAY AFTERNOON...AND MOVE ACROSS THE REGION MONDAY
BRINGING A WIDESPREAD SOAKING RAINFALL AND BREEZY CONDITIONS.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 105 AM...LATEST RUC40 SHOWS SFC LOW MOVING ACROSS RI AND ERN
MA ALONG THE FRONTAL BOUNDARY THAT HAS CLEARED MOST OF THE FCST
AREA. COLDER AIR CONTINUES TO OOZE IN FROM THE NORTHWEST WITH SOME
SNOW BEING REPORTED ON KSLK. THE LATEST REGIONAL AND LOCAL KENX
RADAR IMAGERY SHOWS THE BACK EDGE OF THE PCPN MOVING ACROSS THE
SRN DACKS AND THE WRN MOHAWK VALLEY. THIS SEEMS IN IN SYNC WITH
THE LATEST HRRR 3-KM REF PRODUCT AND THE 00Z NAM. THE HOURLY POPS
WERE RETRENDED ACROSS THE REGION WITH THE PCPN DIMINISHING BTWN
06Z- 09Z...EXCEPT FOR SOME LIGHT RAIN REMAINING OVER THE E/SE
ZONES FROM THE CAPITAL REGION. WE WENT INTO MID-DAY SUNDAY TO
RETREND AND SLOW DOWN THE RAIN RETURNING UNTIL THE AFTERNOON.
THE CURRENT PCPN WAS ENHANCED BY THE LEFT FRONT QUADRANT OF AH
H250 JET STREAK OF 100-120 KTS MOVING ACROSS CNTRL-ERN NY.
RAINFALL REPORTS HAVE RANGED FROM A HALF AN INCH TO UP TO AN INCH
A THIRD FROM THE ERN CATSKILLS NORTHEAST THROUGH THE CAPITAL
REGION...SARATOGA REGION...AND INTO THE NRN TACONICS. THIS IS A
BENEFICIAL RAINFALL AFTER THE PERSISTENT DRY WEATHER THE PAST 3 TO
6 WEEKS. MORE IS ON THE WAVE WITH AN IMPRESSIVE COASTAL WAVE LATER
TODAY THROUGH MONDAY.
LOOK FOR OVERNIGHT LOWS IN THE U30S TO M40S IN MOST PLACES...BUT
LOWER TO MID 30S WELL NORTH AND WEST OF ALBANY OVER THE ADIRONDACK
PARK.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM MONDAY/...
...A STRONG SPRING STORM TO IMPACT THE REGION...
H2O VAPOR LOOP REVEALS THE WEATHER ELEMENTS...A POTENT UPPER LOW
THAT WAS TRACKING ACROSS THE GULF OF MEXICO. A 130+KT UPPER WAS
QUICKLY DIVING SOUTHEAST ACROSS THE PLAINS TOWARD THE MID
MISSISSIPPI RIVER VALLEY. AN ACTIVE COASTAL FRONT ALONG THE
ATLANTIC COASTLINE WAS ALSO IN PLACE TODAY. THESE SYSTEMS ARE
EXPECTED TO PHASE OVER THE SOUTHEAST CONUS WITH A DEEPENING
SURFACE LOW TRACKING NORTHEAST ALONG THE SEABOARD /A NOR`EASTER/.
BEFORE THIS SYSTEM IMPACTS THE REGION...THERE WILL BE A BRIEF LULL
IN THE PRECIP SUNDAY MORNING AS MAIN COLD FRONT IS EAST OF THE
AREA. WE WILL QUICKLY INCREASE THOSE POPS THROUGH THE DAY WITH
RAIN EVOLVING FROM SOUTH TO NORTH THROUGH THE DAY. PRESSURE
GRADIENT WILL BE ON THE INCREASE TOO AS SURFACE LOW DEEPENS FROM
NEAR 1000MB THIS EVENING ACROSS NORTHERN FLORIDA TO ~985MB BY 12Z
MONDAY. QPF FROM THE MODELS APPEAR TO BE SETTLING ALONG THE LINES
OF 1-3 INCHES WITH UPSLOPE ENHANCEMENTS PERHAPS ADDING ANOTHER
INCH TO THOSE TOTALS /SEE HYDRO SECTION BELOW FOR FURTHER DETAILS/.
OTHERWISE...STRONG QG FORCING AND FGEN WILL MAKE FOR BANDS OF
MODERATE TO PERHAPS HEAVY RAINFALL ACROSS THE ENTIRE REGION LATE
SUNDAY INTO EARLY MONDAY MORNING. DRY SLOT APPROACHES DURING THE
DAYLIGHT HOURS MONDAY WHICH WILL SERVE TO DECREASE THE PRECIP
COVERAGE AND INTENSITY ACROSS THE REGION. THE COMBINATION OF A
STRONG SOUTHEAST WIND...DOWNSLOPING COMPONENT COULD BRING A
COMBINATION OF A FEW BINOVCS AND WARMER TEMPERATURES FOR THE
HUDSON RIVER VALLEY.
REGARDING WINDS...AT THIS TIME NO HEADLINES DESPITE THE
STRENGTHENING SOUTH-SOUTHEAST WINDS. CLIMATOLOGY FAVORS PORTIONS
OF THE BERKS...SOUTHERN GREENS AND EASTERN CATSKILLS...BUT IT
SEEMS THE BEST JET CORE MAY REMAIN JUST TO OUR EAST AND WITHIN A
WARM ADVECTION REGIME...DIFFICULT TO MIX DOWN TO THE SURFACE. WE
WILL CONTINUE TO MONITOR TRENDS VERY CLOSELY.
AS THE SURFACE LOW TRACK NOW FURTHER INLAND ACROSS NY AND ACROSS
THE CATSKILLS...BOUNDARY LAYER TEMPERATURES APPEAR TO REMAIN AT OR
ABOVE FREEZING TO REDUCE THE THREAT OF MINOR ACCUMULATING SNOW FOR
THE HIGHER TERRAIN. THEREFORE...WE HAVE GREATLY REDUCED SNOWFALL
AMOUNTS.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
CONDITIONS WILL ONLY GRADUALLY IMPROVE IN THE LONG TERM PERIOD AS
THE LOW PRESSURE SYSTEM RESPONSIBLE FOR ALL OF THE PRECIPITATION
WILL ONLY SLOWLY MOVE AWAY FROM OUR REGION. IT WILL LIKELY TAKE
UNTIL THURSDAY NIGHT AND FRIDAY BEFORE SIGNIFICANT IMPROVEMENT
OCCURS.
MONDAY NIGHT THROUGH TUESDAY NIGHT...CUTOFF UPPER LOW OVER NORTHERN
PA MONDAY NIGHT IS EXPECTED TO DRIFT SLOWLY NORTH ACROSS WESTERN NEW
YORK AND INTO ONTARIO ON TUESDAY. MEANWHILE SURFACE LOW LIFTS FROM
WEST CENTRAL NEW YORK MONDAY EVENING TO SOUTHEAST OF JAMES BAY
TUESDAY EVENING AND THEN EAST OF HUDSON BAY LATE TUESDAY NIGHT.
EXPECT SCATTERED TO NUMEROUS RAIN AND SNOW SHOWERS WITH THE HIGHEST
POPS ACROSS THE NORTHWEST THIRD OF THE FA AND GREATEST CHANCE OF
SNOW SHOWERS AFTER MIDNIGHT MONDAY NIGHT AND TUESDAY NIGHT. LOWS ARE
EXPECTED TO BE IN THE 30S TO AROUND 40 WITH HIGHS ON TUESDAY IN THE
40S TO MID 50S.
WEDNESDAY THROUGH THURSDAY...STILL EXPECT CHANCE POPS AS A SECONDARY
TROUGH AXIS MOVES ACROSS THE AREA WHILE A FAST MOVING LOW PRESSURE
SYSTEM MOVES FROM THE CENTRAL MISSISSIPPI VALLEY WEDNESDAY MORNING
TO THE MID ATLANTIC COAST THURSDAY MORNING. ONCE AGAIN THERE WILL BE
SOME SNOW SHOWERS ACROSS THE NORTHERN MOUNTAINS ESPECIALLY AFTER
MIDNIGHT WEDNESDAY NIGHT. HIGHS WEDNESDAY AND THURSDAY ARE EXPECTED
TO BE IN THE MID 40S TO AROUND 60 WITH LOWS WEDNESDAY NIGHT IN THE
30S TO LOWER 40S...ALTHOUGH SOME UPPER 20S ARE POSSIBLE ACROSS THE
WESTERN ADIRONDACKS.
THURSDAY NIGHT AND FRIDAY...EXPECT GRADUAL IMPROVEMENT AS A RIDGE OF
HIGH PRESSURE SLOWLY BUILDS EAST INTO THE GREAT LAKES REGION. THERE
MAY STILL BE A FEW SCATTERED RAIN OR SNOW SHOWERS CONFINED TO THE
WESTERN ADIRONDACKS MAINLY THURSDAY NIGHT. EXPECT LOWS THURSDAY
NIGHT IN THE UPPER 20S TO AROUND 40 WITH HIGHS ON FRIDAY IN THE MID
40S TO AROUND 60.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
THE FRONTAL BOUNDARY IS TO THE EAST OF THE LOCAL AREA WITH A WEAK
WAVE OF LOW PRESSURE MOVING ALONG IT. THE WAVE WILL MOVE OFF AND
DISSIPATE AND THE BOUNDARY WILL BECOME STALLED JUST OFF THE EAST
COAST OF NEW ENGLAND. PRECIPITATION ACROSS THE AREA WILL DIMINISH
EARLY THIS MORNING CAN SEE SIGNS OF THIS ON RADAR ALREADY. AT KGFL
AND KALB EXPECTED CEILINGS REMAIN LOW...IFR-MVFR THROUGH THE EARLY
MORNING HOURS...WITH MVFR/VFR AT KPOU. WIDESPREAD MVFR ARE EXPECTED
DURING THE DAY INTO THE EVENING.
A STRENGTHEN LOW WILL HEAD NORTHWARD ALONG THE STALLED BOUNDARY UP
THE SOUTHEAST COAST TODAY. THE LOW WILL THEN MOVE NORTHWESTWARD
TONIGHT AS ITS DRAWN IN UNDER THE UPPER LOW THAT WILL HAVE DEVELOPED
DURING THE DAY. THE SYSTEM WILL BECOME VERTICALLY STACKED OVER
CENTRAL PENNSYLVANIA OVERNIGHT. AS THE LOW APPROACHES A WIDESPREAD
RAIN WILL MOVE INTO THE REGION. THE RAIN WILL COME DOWN HEAVY AT
TIMES ESPECIALLY DURING THE EVENING LOWERING CONDITIONS TO
WIDESPREAD IFR.
NORTHERLY WINDS OF AROUND KNOTS TODAY WILL BECOME NORTHEASTERLY
TONIGHT. MAY NEED TO ADD LOW LEVEL WIND SHEAR TO TAF WITH NEXT
ISSUANCE AS A STRONG LOW LEVEL JET MOVES INTO REGION JUST IN ADVANCE
OF THE APPROACHING LOW.
.OUTLOOK...
MON...MVFR/IFR. RAIN SHOWERS IN THE MORNING BECOMING SCATTERED IN
THE AFTERNOON AND IMPROVING TO MVFR/VFR.
MON NIGHT-THU...VFR/MVFR WITH CHANCE OF SHOWERS.
&&
.FIRE WEATHER...
FIRST WIDESPREAD MEASURABLE RAINFALL EXPECTED ACROSS THE ENTIRE
REGION SINCE APRIL 1ST. AN AREA OF LOW PRESSURE WILL APPROACH FROM
THE SOUTH SUNDAY AND MOVE ACROSS THE REGION MONDAY BRINGING A
SOAKING RAINFALL WHICH WILL GREATLY DIMINISHING FIRE WEATHER
CONCERNS.
&&
.HYDROLOGY...
PER THE DROUGHT MONITOR...OUR CWA RANGED FROM D0-D3. THE UPCOMING
RAINFALL EVENT OF 1 TO 3 INCHES...WITH UP TO 4 INCHES ACROSS
FAVORABLE UPSLOPE AREAS OF THE CATSKILLS...SOUTHERN GREENS AND
PORTIONS OF THE BERKS...DROUGHT CONDITIONS ARE EXPECTED TO BE
ALLEVIATED.
A CLOSER EXAMINATION THE MMEFS AND LATEST NERFC GUIDANCE...SEVERAL
RIVER POINTS ARE FORECAST TO RISE TOWARD AND ABOVE FLOOD STAGE.
COMBINE THIS WITH PORTIONS OF THE REGION GROUNDS ABILITY TO ABSORB
WATER IN QUESTION...WE WILL HOIST A FLOOD WATCH FOR PORTIONS OF THE
REGION /MAINLY SOUTH AND EAST OF THE CAPITAL REGION/.
OTHERWISE ANTECEDENT CONDITIONS ARE VERY DRY...PRECIPITATION
DEFICITS ARE RUNNING 5 TO 10 INCHES BELOW NORMAL ACROSS EASTERN
NEW YORK AND WESTERN NEW ENGLAND. STREAMFLOW CONDITIONS ARE AT
WELL BELOW NORMAL AND RESERVOIR LEVELS ACROSS THE AREA REMAIN NEAR
TO SLIGHTLY BELOW NORMAL. THE FORECAST RAINFALL AMOUNTS ARE
EXPECTED TO PRODUCE SIGNIFICANT WITHIN BANK RISES WITH SOME MINOR
FLOODING A POSSIBILITY.
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.
&&
.CLIMATE...
PRECIPITATION (DEPARTURE FROM NORMAL)
ALBANY NY:
MONTH TO DATE THROUGH THE 20TH: 0.14 INCHES (-2.00 INCHES)
SINCE MAR 1: 1.68 INCHES (-3.67 INCHES)
SINCE JAN 1: 4.94 INCHES (-5.20 INCHES)
GLENS FALLS NY:
MONTH TO DATE THROUGH THE 20TH: 0.32 INCHES (-1.63 INCHES)
SINCE MAR 1: 1.55 INCHES (-3.34 INCHES)
SINCE JAN 1: 4.49 INCHES (-5.34 INCHES)
POUGHKEEPSIE NY:
MONTH TO DATE THROUGH THE 20TH: 0.26 INCHES (-2.27 INCHES)
SINCE MAR 1: 1.45 INCHES (-4.65 INCHES)
SINCE JAN 1: 5.06 INCHES (-6.78 INCHES)
BENNINGTON VT:
MONTH TO DATE THROUGH THE 20TH: 0.47 INCHES (-1.79 INCHES)
SINCE MAR 1: 2.05 INCHES (-3.36 INCHES)
SINCE JAN 1: 4.55 INCHES (-5.85 INCHES)
PITTSFIELD MA:
MONTH TO DATE THROUGH THE 20TH: 0.38 INCHES (-2.47 INCHES)
SINCE MAR 1: 1.52 INCHES (-4.70 INCHES)
SINCE JAN 1: 5.73 INCHES (-6.09 INCHES)
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH FROM THIS EVENING THROUGH MONDAY MORNING FOR
CTZ001-013.
NY...FLOOD WATCH FROM THIS EVENING THROUGH MONDAY MORNING FOR
NYZ043-047-053-054-058>061-063>066-084.
MA...FLOOD WATCH FROM THIS EVENING THROUGH MONDAY MORNING FOR
MAZ001-025.
VT...FLOOD WATCH FROM THIS EVENING THROUGH MONDAY MORNING FOR
VTZ013>015.
&&
$$
SYNOPSIS...BGM/WASULA
NEAR TERM...WASULA
SHORT TERM...BGM
LONG TERM...11
AVIATION...IAA
FIRE WEATHER...BGM
HYDROLOGY...BGM/11
CLIMATE...IAA
AREA FORECAST DISCUSSION
NWS ALBANY NY
107 AM EDT SUN APR 22 2012
.SYNOPSIS...
A COLD FRONT CONTINUES TO MOVE SOUTHEAST OF SOUTHERN NEW
YORK AND NEW ENGLAND THIS MORNING...AS A WAVE OF LOW PRESSURE MOVING
ALONG IT CONTINUES TO BRING THE FIRST WIDESPREAD MEASURABLE RAINFALL
SINCE APRIL FIRST. A BRIEF LULL IN THE RAIN WILL OCCUR SUNDAY
MORNING. AN INTENSIFYING AREA OF LOW PRESSURE WILL APPROACH FROM
THE MID ATLANTIC REGION SUNDAY AFTERNOON...AND MOVE ACROSS THE
REGION MONDAY BRINGING A WIDESPREAD SOAKING RAINFALL AND BREEZY
CONDITIONS.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 105 AM...LATEST RUC40 SHOWS SFC LOW MOVING ACROSS RI AND ERN
MA ALONG THE FRONTAL BOUNDARY THAT HAS CLEARED MOST OF THE FCST
AREA. COLDER AIR CONTINUES TO OOZE IN FROM THE NORTHWEST WITH SOME
SNOW BEING REPORTED ON KSLK. THE LATEST REGIONAL AND LOCAL KENX
RADAR IMAGERY SHOWS THE BACK EDGE OF THE PCPN MOVING ACROSS THE
SRN DACKS AND THE WRN MOHAWK VALLEY. THIS SEEMS IN IN SYNC WITH
THE LATEST HRRR 3-KM REF PRODUCT AND THE 00Z NAM. THE HOURLY POPS
WERE RETRENDED ACROSS THE REGION WITH THE PCPN DIMINISHING BTWN
06Z- 09Z...EXCEPT FOR SOME LIGHT RAIN REMAINING OVER THE E/SE
ZONES FROM THE CAPITAL REGION. WE WENT INTO MID-DAY SUNDAY TO
RETREND AND SLOW DOWN THE RAIN RETURNING UNTIL THE AFTERNOON.
THE CURRENT PCPN WAS ENHANCED BY THE LEFT FRONT QUADRANT OF AH
H250 JET STREAK OF 100-120 KTS MOVING ACROSS CNTRL-ERN NY.
RAINFALL REPORTS HAVE RANGED FROM A HALF AN INCH TO UP TO AN INCH
A THIRD FROM THE ERN CATSKILLS NORTHEAST THROUGH THE CAPITAL
REGION...SARATOGA REGION...AND INTO THE NRN TACONICS. THIS IS A
BENEFICIAL RAINFALL AFTER THE PERSISTENT DRY WEATHER THE PAST 3 TO
6 WEEKS. MORE IS ON THE WAVE WITH AN IMPRESSIVE COASTAL WAVE LATER
TODAY THROUGH MONDAY.
LOOK FOR OVERNIGHT LOWS IN THE U30S TO M40S IN MOST PLACES...BUT
LOWER TO MID 30S WELL NORTH AND WEST OF ALBANY OVER THE ADIRONDACK
PARK.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM MONDAY/...
A STRONG SPRING STORM TO IMPACT THE REGION...
H2O VAPOR LOOP REVEALS THE WEATHER ELEMENTS...A POTENT UPPER LOW
THAT WAS TRACKING ACROSS THE GULF OF MEXICO. A 130+KT UPPER WAS
QUICKLY DIVING SOUTHEAST ACROSS THE PLAINS TOWARD THE MID
MISSISSIPPI RIVER VALLEY. AN ACTIVE COASTAL FRONT ALONG THE
ATLANTIC COASTLINE WAS ALSO IN PLACE TODAY. THESE SYSTEMS ARE
EXPECTED TO PHASE OVER THE SOUTHEAST CONUS WITH A DEEPENING
SURFACE LOW TRACKING NORTHEAST ALONG THE SEABOARD /A NOR`EASTER/.
BEFORE THIS SYSTEM IMPACTS THE REGION...THERE WILL BE A BRIEF LULL
IN THE PRECIP SUNDAY MORNING AS MAIN COLD FRONT IS EAST OF THE
AREA. WE WILL QUICKLY INCREASE THOSE POPS THROUGH THE DAY WITH
RAIN EVOLVING FROM SOUTH TO NORTH THROUGH THE DAY. PRESSURE
GRADIENT WILL BE ON THE INCREASE TOO AS SURFACE LOW DEEPENS FROM
NEAR 1000MB THIS EVENING ACROSS NORTHERN FLORIDA TO ~985MB BY 12Z
MONDAY. QPF FROM THE MODELS APPEAR TO BE SETTLING ALONG THE LINES
OF 1-3 INCHES WITH UPSLOPE ENHANCEMENTS PERHAPS ADDING ANOTHER
INCH TO THOSE TOTALS /SEE HYDRO SECTION BELOW FOR FURTHER DETAILS/.
OTHERWISE...STRONG QG FORCING AND FGEN WILL MAKE FOR BANDS OF
MODERATE TO PERHAPS HEAVY RAINFALL ACROSS THE ENTIRE REGION LATE
SUNDAY INTO EARLY MONDAY MORNING. DRY SLOT APPROACHES DURING THE
DAYLIGHT HOURS MONDAY WHICH WILL SERVE TO DECREASE THE PRECIP
COVERAGE AND INTENSITY ACROSS THE REGION. THE COMBINATION OF A
STRONG SOUTHEAST WIND...DOWNSLOPING COMPONENT COULD BRING A
COMBINATION OF A FEW BINOVCS AND WARMER TEMPERATURES FOR THE
HUDSON RIVER VALLEY.
REGARDING WINDS...AT THIS TIME NO HEADLINES DESPITE THE
STRENGTHENING SOUTH-SOUTHEAST WINDS. CLIMATOLOGY FAVORS PORTIONS
OF THE BERKS...SOUTHERN GREENS AND EASTERN CATSKILLS...BUT IT
SEEMS THE BEST JET CORE MAY REMAIN JUST TO OUR EAST AND WITHIN A
WARM ADVECTION REGIME...DIFFICULT TO MIX DOWN TO THE SURFACE. WE
WILL CONTINUE TO MONITOR TRENDS VERY CLOSELY.
AS THE SURFACE LOW TRACK NOW FURTHER INLAND ACROSS NY AND ACROSS
THE CATSKILLS...BOUNDARY LAYER TEMPERATURES APPEAR TO REMAIN AT OR
ABOVE FREEZING TO REDUCE THE THREAT OF MINOR ACCUMULATING SNOW FOR
THE HIGHER TERRAIN. THEREFORE...WE HAVE GREATLY REDUCED SNOWFALL
AMOUNTS.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
CONDITIONS WILL ONLY GRADUALLY IMPROVE IN THE LONG TERM PERIOD AS
THE LOW PRESSURE SYSTEM RESPONSIBLE FOR ALL OF THE PRECIPITATION
WILL ONLY SLOWLY MOVE AWAY FROM OUR REGION. IT WILL LIKELY TAKE
UNTIL THURSDAY NIGHT AND FRIDAY BEFORE SIGNIFICANT IMPROVEMENT
OCCURS.
MONDAY NIGHT THROUGH TUESDAY NIGHT...CUTOFF UPPER LOW OVER NORTHERN
PA MONDAY NIGHT IS EXPECTED TO DRIFT SLOWLY NORTH ACROSS WESTERN NEW
YORK AND INTO ONTARIO ON TUESDAY. MEANWHILE SURFACE LOW LIFTS FROM
WEST CENTRAL NEW YORK MONDAY EVENING TO SOUTHEAST OF JAMES BAY
TUESDAY EVENING AND THEN EAST OF HUDSON BAY LATE TUESDAY NIGHT.
EXPECT SCATTERED TO NUMEROUS RAIN AND SNOW SHOWERS WITH THE HIGHEST
POPS ACROSS THE NORTHWEST THIRD OF THE FA AND GREATEST CHANCE OF
SNOW SHOWERS AFTER MIDNIGHT MONDAY NIGHT AND TUESDAY NIGHT. LOWS ARE
EXPECTED TO BE IN THE 30S TO AROUND 40 WITH HIGHS ON TUESDAY IN THE
40S TO MID 50S.
WEDNESDAY THROUGH THURSDAY...STILL EXPECT CHANCE POPS AS A SECONDARY
TROUGH AXIS MOVES ACROSS THE AREA WHILE A FAST MOVING LOW PRESSURE
SYSTEM MOVES FROM THE CENTRAL MISSISSIPPI VALLEY WEDNESDAY MORNING
TO THE MID ATLANTIC COAST THURSDAY MORNING. ONCE AGAIN THERE WILL BE
SOME SNOW SHOWERS ACROSS THE NORTHERN MOUNTAINS ESPECIALLY AFTER
MIDNIGHT WEDNESDAY NIGHT. HIGHS WEDNESDAY AND THURSDAY ARE EXPECTED
TO BE IN THE MID 40S TO AROUND 60 WITH LOWS WEDNESDAY NIGHT IN THE
30S TO LOWER 40S...ALTHOUGH SOME UPPER 20S ARE POSSIBLE ACROSS THE
WESTERN ADIRONDACKS.
THURSDAY NIGHT AND FRIDAY...EXPECT GRADUAL IMPROVEMENT AS A RIDGE OF
HIGH PRESSURE SLOWLY BUILDS EAST INTO THE GREAT LAKES REGION. THERE
MAY STILL BE A FEW SCATTERED RAIN OR SNOW SHOWERS CONFINED TO THE
WESTERN ADIRONDACKS MAINLY THURSDAY NIGHT. EXPECT LOWS THURSDAY
NIGHT IN THE UPPER 20S TO AROUND 40 WITH HIGHS ON FRIDAY IN THE MID
40S TO AROUND 60.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
LOOKS AS IF MAINLY SUB-VFR CONDITIONS WILL BE THE RULE AT THE TAF
SITES THROUGH SUNDAY.
THE COLD FRONT HAS FINALLY MADE IT TO POUGHKEEPSIE SO NOW THEIR
CEILING SHOULD DROP INTO THE MVFR OR LOW MVFR RANGE. (DECIDED TO
REMOVE ANY MENTION OF IFR). NO CLOUD TO GROUND LIGHTNING LATELY SO
REMOVED THE MENTION OF THUNDER.
BEHIND THE FRONT...IFR CIGS LOOK TO HOLD AT KALB FOR AWHILE
TONIGHT...BEFORE POSSIBLE LIFTING BACK TO LOW MVFR (BELOW 2000
FEET). THAT THINKING IS NOT CERTAIN...ONLY A LITTLE BETTER THAN 50
PERCENT SO CHECK BACK IF YOU MUST INCLUDE IFR RESTRICTION LATER
TONIGHT AT KALB.
AT KGFL...IT APPEARS THAT A DOWNSLOPING NE WIND MIGHT POSSIBLY KEEP
CIGS AND EVEN VSBYS JUST ABOVE IFR. SO FAR THAT IDEA HAS WORKED.
HOWEVER...THIS IS NEARLY A 50/50 BET (WE LEANED A LITTLE HIGHER THAN
THAT) BUT KEPT THEM AT THE LOW MVFR RANGE THROUGH 08Z.
AS WE HEAD TOWARD THE MORNING PEAK ON SUNDAY...CONDITIONS LOOK TO
MARGINALLY IMPROVE AS CIGS ARE FORECAST TO LIFT BACK TO THE HIGH
LEVEL OF MVFR AND FOR AWHILE...ANY RAIN SHOULD END. ENOUGH OF A
NORTH WIND SHOULD PREVENT FOG FROM FORMING AND ANY DRIZZLE WOULD
LIKELY NOT IMPACT VSBYS OR EVEN CIGS TOO MUCH.
LATER ON SUNDAY...THE MAIN STORM WILL BEGIN TO PUSH ITS RAINSHIELD
TOWARD THE TAF SITES BY SUNDAY AFTERNOON. WE DROPPED THE TAFS BACK
FURTHER TOWARD MVFR FOR NOW...STILL JUST ABOVE THE 2000 FOOT MINIMUM
REQUIRED TO CARRY ADDITIONAL FUEL.
.OUTLOOK...
SUN NITE-MON...SUB-VFR CIG RAIN. CHC IFR IN HVY RAIN.
MON NT-WED NT...VFR CIG...CHC SUB-VFR -SHRAS.
THU...VFR. NO SIG WX.
&&
.FIRE WEATHER...
WIDESPREAD MEASURABLE RAINFALL EXPECTED ACROSS THE ENTIRE REGION
SINCE APRIL 1ST. AN AREA OF LOW PRESSURE WILL APPROACH FROM THE SOUTH
SUNDAY AND MOVE ACROSS THE REGION MONDAY BRINGING A SOAKING RAINFALL
WHICH WILL GREATLY DIMINISHING FIRE WEATHER CONCERNS.
&&
.HYDROLOGY...
PER THE DROUGHT MONITOR...OUR CWA RANGED FROM D0-D3. THE UPCOMING
RAINFALL EVENT OF 1 TO 3 INCHES...WITH UP TO 4 INCHES ACROSS
FAVORABLE UPSLOPE AREAS OF THE CATSKILLS...SOUTHERN GREENS AND
PORTIONS OF THE BERKS...DROUGHT CONDITIONS ARE EXPECTED TO BE
ALLEVIATED.
A CLOSER EXAMINATION THE MMEFS AND LATEST NERFC
GUIDANCE...SEVERAL RIVER POINTS ARE FORECAST TO RISE TOWARD AND
ABOVE FLOOD STAGE. COMBINE THIS WITH PORTIONS OF THE REGION
GROUNDS ABILITY TO ABSORB WATER IN QUESTION...WE WILL HOIST A
FLOOD WATCH FOR PORTIONS OF THE REGION /MAINLY SOUTH AND EAST OF
THE CAPITAL REGION/.
OTHERWISE ANTECEDENT CONDITIONS ARE VERY DRY...PRECIPITATION
DEFICITS ARE RUNNING 5 TO 10 INCHES BELOW NORMAL ACROSS EASTERN
NEW YORK AND WESTERN NEW ENGLAND. STREAMFLOW CONDITIONS ARE AT
WELL BELOW NORMAL AND RESERVOIR LEVELS ACROSS THE AREA REMAIN NEAR
TO SLIGHTLY BELOW NORMAL. THE FORECAST RAINFALL AMOUNTS ARE
EXPECTED TO PRODUCE SIGNIFICANT WITHIN BANK RISES WITH SOME MINOR
FLOODING A POSSIBILITY.
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.
&&
.CLIMATE...
PRECIPITATION (DEPARTURE FROM NORMAL)
ALBANY NY:
MONTH TO DATE THROUGH THE 20TH: 0.14 INCHES (-2.00 INCHES)
SINCE MAR 1: 1.68 INCHES (-3.67 INCHES)
SINCE JAN 1: 4.94 INCHES (-5.20 INCHES)
GLENS FALLS NY:
MONTH TO DATE THROUGH THE 20TH: 0.32 INCHES (-1.63 INCHES)
SINCE MAR 1: 1.55 INCHES (-3.34 INCHES)
SINCE JAN 1: 4.49 INCHES (-5.34 INCHES)
POUGHKEEPSIE NY:
MONTH TO DATE THROUGH THE 20TH: 0.26 INCHES (-2.27 INCHES)
SINCE MAR 1: 1.45 INCHES (-4.65 INCHES)
SINCE JAN 1: 5.06 INCHES (-6.78 INCHES)
BENNINGTON VT:
MONTH TO DATE THROUGH THE 20TH: 0.47 INCHES (-1.79 INCHES)
SINCE MAR 1: 2.05 INCHES (-3.36 INCHES)
SINCE JAN 1: 4.55 INCHES (-5.85 INCHES)
PITTSFIELD MA:
MONTH TO DATE THROUGH THE 20TH: 0.38 INCHES (-2.47 INCHES)
SINCE MAR 1: 1.52 INCHES (-4.70 INCHES)
SINCE JAN 1: 5.73 INCHES (-6.09 INCHES)
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH FROM THIS EVENING THROUGH MONDAY MORNING FOR
CTZ001-013.
NY...FLOOD WATCH FROM THIS EVENING THROUGH MONDAY MORNING FOR
NYZ043-047-053-054-058>061-063>066-084.
MA...FLOOD WATCH FROM THIS EVENING THROUGH MONDAY MORNING FOR
MAZ001-025.
VT...FLOOD WATCH FROM THIS EVENING THROUGH MONDAY MORNING FOR
VTZ013>015.
&&
$$
SYNOPSIS...BGM/WASULA
NEAR TERM...WASULA
SHORT TERM...BGM
LONG TERM...11
AVIATION...HWJIV
FIRE WEATHER...BGM
HYDROLOGY...BGM/11
CLIMATE...IAA
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
134 PM EDT SUN APR 22 2012
.SYNOPSIS...
A LOW PRESSURE SYSTEM JUST OFF THE SOUTH CAROLINA COAST WILL INTENSIFY
AS IT MOVES NORTH PASSING THROUGH THE AREA LATE TONIGHT AND MONDAY.
THE LOW WILL THEN DRIFT NORTH INTO NEW YORK AND CANADA AS IT SLOWLY
WEAKENS. ANOTHER LOW PRESSURE SYSTEM FROM THE GREAT PLAINS SHOULD
PASS JUST SOUTH OF THE REGION WEDNESDAY NIGHT AND THURSDAY. A HIGH
PRESSURE SYSTEM FROM CENTRAL CANADA IS EXPECTED TO BUILD INTO THE
AREA FOR THE END OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE HEAVY RAIN IS EASING INTO SOUTHERN DELAWARE...WITH MORE HEAVY
RAIN ACROSS SOUTHERN VIRGINIA AND OFF THE NORTH CAROLINA COAST. AS
THE THETA E RICH AIR CONTINUES TO RIDE NORTH AHEAD OF THE BOTTOM
OF THE NEGATIVELY TITLED LONG WAVE TROUGH...HEAVY RAIN WILL
CONTINUE TO MOVE NORTH. THE 1200 UTC NAM IS STILL SHOWING NEARLY
2.5O INCHES OF RAIN FALLING IN THE BASINS OF THE FASTER REACTING
STREAMS OF SOUTHEAST PENNSYLVANIA AND NORTHERN DELAWARE. THIS
NUMBER IS ABOUT WHAT WOULD BE NEEDED TO PUSH SOME OF THE FASTER
RESPONDERS OVER THEIR BANKS. THE FLOOD WATCH WILL REMAIN IN
EFFECT...THOUGH IT COULD BE THAT THE NORTHEAST PART OF THE WATCH
MAY NOT SEE ENOUGH RAIN FOR FLOODING OF SMALL RAIN...BASED ON 1200
UTC NAM AND TRENDS. HOWEVER...THE FLOOD WATCH STAYS AS IT IS NOT
CLEAR THAT A SHIFT IN THE QPF MAXIMUM WOULD NOT PUT THESE
LOCATIONS IN POSITION FOR FLOODING OF STREAM AND CREEKS.
THE WIND FORECAST REMAINS UNCHANGED. THE LATEST HRRR SHOWS THE
BEST GRADIENT AND ASSOCIATED WIND FIELD REACHING SOUTHERN DELAWARE
AND SOUTHERNMOST NEW JERSEY TOWARD 2300 UTC. THE STRONGEST WINDS
SHOULD OCCUR LATE AFTERNOON ACROSS SOUTHERN AREAS...AND EXIT NEW
JERSEY BEFORE 0600 UTC.
WITH THE NORTHEAST LOW LEVEL FLOW...TEMPERATURES PROBABLY DO NOT
RISE ALL THAT MUCH TODAY. THIS THINKING HAS BEEN REFLECTED IN THE
HIGH TEMPERATURE FORECAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
THE HEAVY RAINS WILL CONTINUE THIS EVENING...THEN END FROM SOUTH TO
NORTH. THE LOW WILL PASS ACROSS NJ THEN CURVE NW BACK TOWARD THE
POCONOS BY 12Z MON. DRIER AIR WILL WRAP AROUND FROM THE WEST AND
MOVE ACROSS THE SRN HALF OF THE REGION...ENDING THE HEAVY RAINS.
WINDS WILL REMAIN GUSTY...SHIFTING TO WRLY OR SWRLY BEHIND THE
DEPARTING LOW. THE STRONGEST WINDS WILL SUBSIDE AFTER MIDNIGHT...SO
THE WIND ADVISORY HAS BEEN ISSUED UNTIL 400 AM FOR NOW...IT CAN BE
ADJUSTED ON UPCOMING FCSTS. OVERNIGHT LOWS WILL DROP 5 TO 10 DEGREES
FROM SUNDAYS HIGHS...REACHING THE LOW 40S OVER THE SRN POCONOS AND
MID 40S ELSEWHERE.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
THE GFS AND WRF-NMMB INITIALIZATION LOOKED ABOUT EVEN BUT NOT
PERFECT WITH THE TROF IN THE OH AND TN VALLEYS AND GULF COAST, IF
ANYTHING SUGGESTING A SLIGHTLY SLOWER EVOLUTION. CONVERSELY AT
850MB AND 925MB THE GFS LOOKED BETTER THAN THE WRF-NMMB.
AT THE START OF MONDAY MORNING, THE HEAVY RAIN SHOULD BE JUST
ABOUT EXITING IF NOT ALREADY EXITED OUR CWA. THEN INTO TUESDAY WE
ARE STUCK WITH THE METEOROLOGICAL HANGOVER FROM THIS INTENSE
SYSTEM AS IT SLOWLY WEAKENS AND DRIFTS AWAY FROM THE NERN CONUS.
GIVEN THAT THE GFS IS LIKELY TOO FAST WITH THE SFC LOW, IT IS LIKELY
TOO FAST WITH ADVECTING THE COLD AIR IN FROM THE SOUTHWEST ON
MONDAY. SMALL CONSOLATION AS BOTH IT AND THE WRF-NMMB ARE IN SELF
DESTRUCT SUNSHINE MODE WITH THE COLD POOL ALOFT IN PLACE. PTYPE
SHOULD BE RAIN SHOWERS AS WE SHOULD STILL BE TOO WARM IN THE
BOUNDARY LAYER. IT WILL BE A WINDY DAY AND GUSTS WILL LIKELY
EXCEED 30 MPH. THE GFS IS SLIGHTLY MORE ROBUST WITH THE WINDS AND
TAKE US CLOSE TO WIND ADVY CRITERIA. BECAUSE THE GFS IS LIKELY TOO
FAST, WE COMPROMISED ON THE STAT GUIDANCE FOR MAX TEMPS.
WHILE WE WILL LOSE WHAT APPEARS TO BE LIMITED SUN ON MONDAY, THERE
WILL STILL BE SOME SHORT WAVES ROTATING AROUND THE SLOW TO DEPART
CLOSED LOW MONDAY NIGHT. DEEPEST MOISTURE IS NW WHERE WE KEPT
POPS THRU THE NIGHT. BY MONDAY NIGHT SOME SNOW SHOWERS ARE
POSSIBLE NW OVER THE HIGHER TERRAIN. A TOBYHANNA ACCUMULATION
WOULD NOT BE A SHOCKER BY TUESDAY MORNING.
TUESDAY LOOKS TO BE A REPEAT OF MONDAY WITH SLIGHTLY LESS WIND AND A
FEW LESS SHOWERS AROUND. MEASURABLE POPS ARE FORECAST TO BE 20 TO 40
PCT LESS THAN MONDAY AND ANY AMOUNTS SHOULD ALSO BE LIGHTER WITH
HEIGHTS STARTING TO RECOVER ALOFT AND COLDER TEMPERATURES AT
850MB. HERE THE GFS AIR MASS RECOVERY MAY BE A BIT TOO FAST AND WE
COMPROMISED ON THE STAT GUIDANCE IN THE OPPOSITE DIRECTION.
THE WEAKENING TROF AXIS SHOULD CLEAR OUR CWA BY TUESDAY NIGHT, JUST
IN TIME FOR THE NEXT SYSTEM TO START ARRIVING. WE MAINTAINED
CONTINUITY IN THE REST OF THE LONG TERM EMPHASIZING WEDNESDAY NIGHT
AS THE MOST LIKELY PERIOD FOR THE NEXT PCPN SHOT WITH CHILLIER THAN
NORMAL, BUT FAIR WEATHER FOR THE END OF THE WEEK.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
CONDITIONS HAVE BEEN SLOW TO DROP TO (OR STAY) AT MVFR AT KRDG AND
KABE...BUT THIS SHOULD BE TRANSIENT AS THE LOWER INVERSION SHOULD
ENSURE MVFR CONDITIONS THERE SOON. ELSEWHERE...CONDITIONS ARE
TRANSITING FROM IFR TO LIFR (MAINLY DUE TO CEILINGS). ONCE CEILINGS
DROP TO LIFR...THEY WILL STAY THERE THROUGH THE PASSAGE OF THE LOW
LATER TONIGHT.
WINDS WILL START TO BECOME AN ISSUE FOR ALL TERMINALS AFTER 2200 UTC
AND THE SURFACE LOW APPROACHES. FOR MOST LOCATIONS...WIND GUSTS
BETWEEN 25 AND 34 KNOTS ARE EXPECTED (HIGHEST EAST AND LOWEST WEST)
BETWEEN 0000 UTC AND 0600 UTC. THERE IS SOME SPREAD ON JUST WHERE
THE SURFACE LOW PASSES...AND THIS WILL HAVE A SIGNIFICANT IMPACT ON
WIND DIRECTION AFTER 0600 UTC. FORTUNATELY...BY THAT TIME...THE WIND
SPEEDS SHOULD COME DOWN AND NOT BE AS MUCH OF A FACTOR.
AS THE SURFACE LOW PULLS FURTHER INTO PENNSYLVANIA AND NEW YORK
STATE MONDAY MORNING...WINDS SHOULD SHIFT TO SOUTHWEST JUST ABOUT
EVERYWHERE. GUSTS WILL BEGIN AFTER 1500 UTC...AND GUSTS AS HIGH AS
30 KNOTS ARE POSSIBLE AFTER 1700 UTC. CEILINGS WILL START LIFR IN
ALL LOCATION. IMPROVEMENT WILL BE SLOW...AND IFR CONDITIONS ARE
EXPECTED FROM SOUTHWEST TO NORTHEAST DURING THE MORNING. MVFR
CONDITIONS ARE POSSIBLE AFTER 1800 UTC...BUT CONFIDENCE IN THIS IS
LOW.
OUTLOOK...
TUE...VFR CONDITIONS ARE EXPECTED. LOCAL MVFR CONDITIONS ARE
POSSIBLE IN ISOLATED TO SCATTERED SHOWERS...BUT CONFIDENCE IN THIS
IS LOW.
WED...VFR CONDITIONS ARE EXPECTED. MVFR CONDITIONS ARE POSSIBLE
WEDNESDAY NIGHT...ESPECIALLY SOUTH IN POSSIBLE RAIN.
THU...MVFR CONDITIONS ARE POSSIBLE...ESPECIALLY SOUTH IN THE
MORNING. VFR CONDITIONS ARE EXPECTED IN THE AFTERNOON AND AT
NIGHT.
&&
.MARINE...
WINDS AND SEAS SHOULD REMAIN SUB-SCA THIS MORNING...THEN RAMP UP
TO GALES BY LATE AFTERNOON OVER THE WATERS. A GALE WAS ALSO ISSUED
FOR THE NRN DEL BAY...WHERE SOME G40 WILL LIKELY AFFECT SJSN4. THE
GALES CONTINUE OVER THE DEL BAY AND SRN COASTAL WATERS THRU 06Z MON
AND CONTINUE THRU 09Z MON FOR THE NRN 2 COASTAL WATERS ZONES. SCA
FLAGS WILL LIKELY BE ISSUED ONCE THE GALE FLAGS ARE TAKEN DOWN.
OUTLOOK...
WE MIGHT HAVE ANOTHER PERIOD OF GALE FORCE WIND GUSTS ON MONDAY IN
THE WESTERLY FLOW. AIR TEMPERATURES ARE GOING TO BE RELATIVELY HIGH,
SO CONFIDENCE NOT HIGH. AT THE LEAST SMALL CRAFT ADVISORY CRITERIA
WINDS SHOULD PERSIST INTO TUESDAY DAY UNTIL THE LOW PRESSURE SYSTEM
FINALLY DEPARTS FROM THE REGION. WINDS AND SEAS SHOULD BE BELOW
SMALL CRAFT ADVISORY CRITERIA ON WEDNESDAY, BUT DEPENDING UPON HOW
STRONG THAT CLIPPER TYPE LOW PRESSURE SYSTEM IS, WE MIGHT REACH
SMALL CRAFT ADVISORY CRITERIA AGAIN WEDNESDAY NIGHT OR THURSDAY.
&&
.HYDROLOGY...
THE FLOOD WATCH REMAINS IN EFFECT. PCPN AMOUNTS FROM THE COLD
FRONTAL PASSAGE THUNDERSTORMS AVERAGED BETWEEN ONE QUARTER AND
HALF AN INCH.
WHILE WE HAVE BEEN DRY...ALL OF THE INGREDIENTS FOR HEAVY RAIN ARE
COMING TOGETHER FOR MUCH OF THE AREA. THE SOURCE OF THE AIR RIDING
UP THE FRONT OF THE MID LEVEL TROUGH IS THE EASTERN GULF STATES...
AND PRECIPITABLE WATER VALUES APPROACH 1.50 INCHES LATER SUNDAY INTO
SUNDAY NIGHT. THE HIGHEST PRECIPITABLE WATER VALUES ARE SUPERIMPOSED
WITH THE LOW TO MID LEVEL THETA E RIDGE POKING INTO EASTERN
PENNSYLVANIA AND NORTHERN NEW JERSEY DURING ROUGHLY THE SAME TIME.
STORM TOTAL RAINFALL AMOUNTS OF 2 TO 3.5 INCHES OF RAIN ARE
EXPECTED. THE INITIAL SHOT OF HEAVY RAIN AFFECTS SOUTHERN AREAS
DURING THE AFTERNOON. RAINFALL AMOUNTS IN THIS SHOT COULD APPROACH
2.5 INCHES ACROSS PORTIONS OF NORTHERN DELAWARE AND SOUTHEAST
PENNSYLVANIA. THESE QPF NUMBERS PUSH SOME OF THE FLASHIER STREAMS
AND SMALL RIVERS (SUCH AS THE CHRISTINA) ABOVE THEIR BANKS.
THIS IS THE REASON NORTHERN DELAWARE AND MUCH OF SOUTHEAST
PENNSYLVANIA WERE INCLUDED IN THE WATCH.
FARTHER NORTH...WHERE THE RICH THETA RICH AIR PUSHES IN DURING
THE LATE AFTERNOON AND EARLY EVENING...HIGHER QPF VALUES ARE
EXPECTED. IN THESE AREAS...STORM TOTAL RAINFALL VALUES CLOSE TO
3.5 INCHES ARE POSSIBLE IN PLACES IN MORRIS COUNTY. WHILE THIS
MUCH RAIN DOES NOT RESULT IN MAINSTEM RIVER FLOODING...SMALLER
RIVERS AND STREAMS (SUCH AS THOSE IN MORRIS COUNTY) SHOULD RESPOND
QUICKLY TO THESE AMOUNTS. IF CLOSER TO 4 INCHES OF RAIN FALLS IN
THE PASSAIC BASIN...MAINSTEM FLOODING COULD BECOME POSSIBLE.
THE HEAVIEST RAIN TAPERS OFF FROM SOUTHWEST TO NORTHEAST LATE SUNDAY
EVENING INTO EARLY MONDAY MORNING. THE FLOOD WATCH WAS EXTENDED
THROUGH MUCH OF THE NIGHT TO ALLOW FOR THE RAINFALL TO WORK ITS WAY
THROUGH THE SYSTEM.
RUNNING SOME CONTINGENT FORECASTS AND USING SOME MMEFS DATA, THESE
ARE SOME NUMBERS TO WATCH FOR (BASIN-WIDE AVERAGES) FOR POTENTIAL
FLOODING...
QUICK RESPONDERS ACROSS SE PA AND NRN DE...2.25 TO 2.50"
SLOWER RESPONDERS ACROSS SE PA...3.00"
RANCOCAS BASIN...3.00"
RARITAN BASIN...3.75"
PASSAIC BASIN...4.00"
LEHIGH BASIN...4.00+"
POCONOS...4.00+"
&&
.TIDES/COASTAL FLOODING...
WE WILL ISSUE A COASTAL FLOOD ADVISORY FOR THE OCEAN, DELAWARE BAY
AND TIDAL SECTIONS OF THE DELAWARE RIVER FOR TONIGHT`S HIGH TIDE
CYCLE. WHILE THE SURGE GUIDANCE HAS OUR AREA JUST GETTING OR
FALLING A BIT SHORT OF THE NEEDED CRITERIA, OUR LOCAL STUDY PROGRAM
TAKES TIDAL DEPARTURES HALFWAY INTO THE MINOR TIDAL FLOODING
CRITERIA SOUTH WITH LESS DEPARTURES FARTHER NORTH. SO LEAST
CONFIDENCE UP TOWARD NYC, WILL DEPEND UPON HOW QUICKLY WINDS
INCREASE LEADING INTO THE HIGH TIDE CYCLE. THE ADDED COMPLICATION
WILL BE THAT HEAVY RAIN WILL BE ONGOING DURING THE HIGH TIDE CYCLE.
WE ARE GOING TO HOLD OFF ON CHESAPEAKE BAY AS THE HIGHER
ASTRONOMICAL TIDE IS DURING THE DAY ON MONDAY. THE CBOFS
GUIDANCE IS FORECASTING MINOR TIDAL FLOODING, BUT IT TENDS TO RUN A
BIT TOO HIGH.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FLOOD WATCH THROUGH LATE TONIGHT FOR PAZ067>071.
COASTAL FLOOD ADVISORY FROM MIDNIGHT TONIGHT TO 5 AM EDT
MONDAY FOR PAZ070-071.
NJ...FLOOD WATCH THROUGH LATE TONIGHT FOR NJZ008>010-012-015.
WIND ADVISORY UNTIL 4 AM EDT MONDAY FOR NJZ012>027.
COASTAL FLOOD ADVISORY FROM 8 PM THIS EVENING TO MIDNIGHT EDT
TONIGHT FOR NJZ012>014-020-022>027.
COASTAL FLOOD ADVISORY FROM MIDNIGHT TONIGHT TO 5 AM EDT
MONDAY FOR NJZ016>019-021.
DE...FLOOD WATCH THROUGH LATE TONIGHT FOR DEZ001.
WIND ADVISORY UNTIL 4 AM EDT MONDAY FOR DEZ001>004.
COASTAL FLOOD ADVISORY FROM 8 PM THIS EVENING TO MIDNIGHT EDT
TONIGHT FOR DEZ003-004.
COASTAL FLOOD ADVISORY FROM MIDNIGHT TONIGHT TO 5 AM EDT
MONDAY FOR DEZ001-002.
MD...NONE.
MARINE...GALE WARNING FROM 5 PM THIS AFTERNOON TO 2 AM EDT MONDAY FOR
ANZ430-431-452>455.
GALE WARNING FROM 5 PM THIS AFTERNOON TO 5 AM EDT MONDAY FOR
ANZ450-451.
&&
$$
SYNOPSIS...GIGI/HAYES
NEAR TERM...HAYES
SHORT TERM...O`HARA
LONG TERM...GIGI/HAYES
AVIATION...GIGI/HAYES/O`HARA
MARINE...HAYES/O`HARA
HYDROLOGY...GIGI
TIDES/COASTAL FLOODING...GIGI
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1215 PM EDT SUN APR 22 2012
.SYNOPSIS...
A LOW PRESSURE SYSTEM JUST OFF THE SOUTH CAROLINA COAST WILL INTENSIFY
AS IT MOVES NORTH PASSING THROUGH THE AREA LATE TONIGHT AND MONDAY.
THE LOW WILL THEN DRIFT NORTH INTO NEW YORK AND CANADA AS IT SLOWLY
WEAKENS. ANOTHER LOW PRESSURE SYSTEM FROM THE GREAT PLAINS SHOULD
PASS JUST SOUTH OF THE REGION WEDNESDAY NIGHT AND THURSDAY. A HIGH
PRESSURE SYSTEM FROM CENTRAL CANADA IS EXPECTED TO BUILD INTO THE
AREA FOR THE END OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE HEAVY RAIN IS EASING INTO SOUTHERN DELAWARE...WITH MORE HEAVY
RAIN ACROSS SOUTHERN VIRGINIA AND OFF THE NORTH CAROLINA COAST. AS
THE THETA E RICH AIR CONTINUES TO RIDE NORTH AHEAD OF THE BOTTOM
OF THE NEGATIVELY TITLED LONG WAVE TROUGH...HEAVY RAIN WILL
CONTINUE TO MOVE NORTH. THE 1200 UTC NAM IS STILL SHOWING NEARLY
2.5O INCHES OF RAIN FALLING IN THE BASINS OF THE FASTER REACTING
STREAMS OF SOUTHEAST PENNSYLVANIA AND NORTHERN DELAWARE. THIS
NUMBER IS ABOUT WHAT WOULD BE NEEDED TO PUSH SOME OF THE FASTER
RESPONDERS OVER THEIR BANKS. THE FLOOD WATCH WILL REMAIN IN
EFFECT...THOUGH IT COULD BE THAT THE NORTHEAST PART OF THE WATCH
MAY NOT SEE ENOUGH RAIN FOR FLOODING OF SMALL RAIN...BASED ON 1200
UTC NAM AND TRENDS. HOWEVER...THE FLOOD WATCH STAYS AS IT IS NOT
CLEAR THAT A SHIFT IN THE QPF MAXIMUM WOULD NOT PUT THESE
LOCATIONS IN POSITION FOR FLOODING OF STREAM AND CREEKS.
THE WIND FORECAST REMAINS UNCHANGED. THE LATEST HRRR SHOWS THE
BEST GRADIENT AND ASSOCIATED WIND FIELD REACHING SOUTHERN DELAWARE
AND SOUTHERNMOST NEW JERSEY TOWARD 2300 UTC. THE STRONGEST WINDS
SHOULD OCCUR LATE AFTERNOON ACROSS SOUTHERN AREAS...AND EXIT NEW
JERSEY BEFORE 0600 UTC.
WITH THE NORTHEAST LOW LEVEL FLOW...TEMPERATURES PROBABLY DO NOT
RISE ALL THAT MUCH TODAY. THIS THINKING HAS BEEN REFLECTED IN THE
HIGH TEMPERATURE FORECAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
THE HEAVY RAINS WILL CONTINUE THIS EVENING...THEN END FROM SOUTH TO
NORTH. THE LOW WILL PASS ACROSS NJ THEN CURVE NW BACK TOWARD THE
POCONOS BY 12Z MON. DRIER AIR WILL WRAP AROUND FROM THE WEST AND
MOVE ACROSS THE SRN HALF OF THE REGION...ENDING THE HEAVY RAINS.
WINDS WILL REMAIN GUSTY...SHIFTING TO WRLY OR SWRLY BEHIND THE
DEPARTING LOW. THE STRONGEST WINDS WILL SUBSIDE AFTER MIDNIGHT...SO
THE WIND ADVISORY HAS BEEN ISSUED UNTIL 400 AM FOR NOW...IT CAN BE
ADJUSTED ON UPCOMING FCSTS. OVERNIGHT LOWS WILL DROP 5 TO 10 DEGREES
FROM SUNDAYS HIGHS...REACHING THE LOW 40S OVER THE SRN POCONOS AND
MID 40S ELSEWHERE.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
THE GFS AND WRF-NMMB INITIALIZATION LOOKED ABOUT EVEN BUT NOT
PERFECT WITH THE TROF IN THE OH AND TN VALLEYS AND GULF COAST, IF
ANYTHING SUGGESTING A SLIGHTLY SLOWER EVOLUTION. CONVERSELY AT
850MB AND 925MB THE GFS LOOKED BETTER THAN THE WRF-NMMB.
AT THE START OF MONDAY MORNING, THE HEAVY RAIN SHOULD BE JUST
ABOUT EXITING IF NOT ALREADY EXITED OUR CWA. THEN INTO TUESDAY WE
ARE STUCK WITH THE METEOROLOGICAL HANGOVER FROM THIS INTENSE
SYSTEM AS IT SLOWLY WEAKENS AND DRIFTS AWAY FROM THE NERN CONUS.
GIVEN THAT THE GFS IS LIKELY TOO FAST WITH THE SFC LOW, IT IS LIKELY
TOO FAST WITH ADVECTING THE COLD AIR IN FROM THE SOUTHWEST ON
MONDAY. SMALL CONSOLATION AS BOTH IT AND THE WRF-NMMB ARE IN SELF
DESTRUCT SUNSHINE MODE WITH THE COLD POOL ALOFT IN PLACE. PTYPE
SHOULD BE RAIN SHOWERS AS WE SHOULD STILL BE TOO WARM IN THE
BOUNDARY LAYER. IT WILL BE A WINDY DAY AND GUSTS WILL LIKELY
EXCEED 30 MPH. THE GFS IS SLIGHTLY MORE ROBUST WITH THE WINDS AND
TAKE US CLOSE TO WIND ADVY CRITERIA. BECAUSE THE GFS IS LIKELY TOO
FAST, WE COMPROMISED ON THE STAT GUIDANCE FOR MAX TEMPS.
WHILE WE WILL LOSE WHAT APPEARS TO BE LIMITED SUN ON MONDAY, THERE
WILL STILL BE SOME SHORT WAVES ROTATING AROUND THE SLOW TO DEPART
CLOSED LOW MONDAY NIGHT. DEEPEST MOISTURE IS NW WHERE WE KEPT
POPS THRU THE NIGHT. BY MONDAY NIGHT SOME SNOW SHOWERS ARE
POSSIBLE NW OVER THE HIGHER TERRAIN. A TOBYHANNA ACCUMULATION
WOULD NOT BE A SHOCKER BY TUESDAY MORNING.
TUESDAY LOOKS TO BE A REPEAT OF MONDAY WITH SLIGHTLY LESS WIND AND A
FEW LESS SHOWERS AROUND. MEASURABLE POPS ARE FORECAST TO BE 20 TO 40
PCT LESS THAN MONDAY AND ANY AMOUNTS SHOULD ALSO BE LIGHTER WITH
HEIGHTS STARTING TO RECOVER ALOFT AND COLDER TEMPERATURES AT
850MB. HERE THE GFS AIR MASS RECOVERY MAY BE A BIT TOO FAST AND WE
COMPROMISED ON THE STAT GUIDANCE IN THE OPPOSITE DIRECTION.
THE WEAKENING TROF AXIS SHOULD CLEAR OUR CWA BY TUESDAY NIGHT, JUST
IN TIME FOR THE NEXT SYSTEM TO START ARRIVING. WE MAINTAINED
CONTINUITY IN THE REST OF THE LONG TERM EMPHASIZING WEDNESDAY NIGHT
AS THE MOST LIKELY PERIOD FOR THE NEXT PCPN SHOT WITH CHILLIER THAN
NORMAL, BUT FAIR WEATHER FOR THE END OF THE WEEK.
&&
.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
CONDITIONS ARE DROPPING TO MVFR (AFTER A COUPLE OF HOURS OF VFR
CEILINGS). THE STEADIER RAIN IS ABOUT TO MOVE INTO THE KPHL METRO
AREA AIRPORTS. BASED ON UPSTREAM OBSERVATIONS...IT SHOULD TAKE
ABOUT 2 HOURS AFTER THE ONSET OF STEADY RAIN TO DROP VISIBILITY
VALUES TO MVFR.
AGAIN...BASED ON THE TRENDS TO THE SOUTH...CEILINGS SHOULD DROP
TO IFR AFTER 1800 UTC...PROBABLY REACHING KPHL AFTER 1900 UTC.
ONCE CONDITIONS DROP TO IFR...THEY WILL LIKELY STAY IN THAT
CATEGORY FOR THE REST OF TONIGHT AND MUCH OF TONIGHT.
WINDS WILL START TO BECOME AN ISSUE AFTER 2100 UTC. GUSTS OVER 25
KNOTS PROBABLY BEGIN AFTER 1900 UTC...AND WITH GUSTS TO 35 KNOTS
AT KACY AND KMIV POSSIBLY AFTER 2300 UTC. AT THIS TIME...IT
APPEARS AS THOUGH THE STRONGEST WINDS GUSTS AFFECT KACY AND KMIV
BETWEEN 2300 UTC AND 0300 UTC.
OUTLOOK...
MON...IFR CONDITIONS EARLY IN THE MORNING..IMPROVING TO MVFR AND
VFR BY THE AFTERNOON. SW TO W WINDS COULD GUST TO 30 KNOTS...ESPECIALLY
DURING THE AFTERNOON AND EVENING.
TUE...VFR CONDITIONS ARE EXPECTED. LOCAL MVFR CONDITIONS ARE
POSSIBLE IN ISOLATED TO SCATTERED SHOWERS...BUT CONFIDENCE IN THIS
IS LOW.
WED...VFR CONDITIONS ARE EXPECTED. MVFR CONDITIONS ARE POSSIBLE
WEDNESDAY NIGHT...ESPECIALLY SOUTH IN POSSIBLE RAIN.
THU...MVFR CONDITIONS ARE POSSIBLE...ESPECIALLY SOUTH IN THE
MORNING. VFR CONDITIONS ARE EXPECTED IN THE AFTERNOON AND AT
NIGHT.
&&
.MARINE...
WINDS AND SEAS SHOULD REMAIN SUB-SCA THIS MORNING...THEN RAMP UP
TO GALES BY LATE AFTERNOON OVER THE WATERS. A GALE WAS ALSO ISSUED
FOR THE NRN DEL BAY...WHERE SOME G40 WILL LIKELY AFFECT SJSN4. THE
GALES CONTINUE OVER THE DEL BAY AND SRN COASTAL WATERS THRU 06Z MON
AND CONTINUE THRU 09Z MON FOR THE NRN 2 COASTAL WATERS ZONES. SCA
FLAGS WILL LIKELY BE ISSUED ONCE THE GALE FLAGS ARE TAKEN DOWN.
OUTLOOK...
WE MIGHT HAVE ANOTHER PERIOD OF GALE FORCE WIND GUSTS ON MONDAY IN
THE WESTERLY FLOW. AIR TEMPERATURES ARE GOING TO BE RELATIVELY HIGH,
SO CONFIDENCE NOT HIGH. AT THE LEAST SMALL CRAFT ADVISORY CRITERIA
WINDS SHOULD PERSIST INTO TUESDAY DAY UNTIL THE LOW PRESSURE SYSTEM
FINALLY DEPARTS FROM THE REGION. WINDS AND SEAS SHOULD BE BELOW
SMALL CRAFT ADVISORY CRITERIA ON WEDNESDAY, BUT DEPENDING UPON HOW
STRONG THAT CLIPPER TYPE LOW PRESSURE SYSTEM IS, WE MIGHT REACH
SMALL CRAFT ADVISORY CRITERIA AGAIN WEDNESDAY NIGHT OR THURSDAY.
&&
.HYDROLOGY...
THE FLOOD WATCH REMAINS IN EFFECT. PCPN AMOUNTS FROM THE COLD
FRONTAL PASSAGE THUNDERSTORMS AVERAGED BETWEEN ONE QUARTER AND
HALF AN INCH.
WHILE WE HAVE BEEN DRY...ALL OF THE INGREDIENTS FOR HEAVY RAIN ARE
COMING TOGETHER FOR MUCH OF THE AREA. THE SOURCE OF THE AIR RIDING
UP THE FRONT OF THE MID LEVEL TROUGH IS THE EASTERN GULF STATES...
AND PRECIPITABLE WATER VALUES APPROACH 1.50 INCHES LATER SUNDAY INTO
SUNDAY NIGHT. THE HIGHEST PRECIPITABLE WATER VALUES ARE SUPERIMPOSED
WITH THE LOW TO MID LEVEL THETA E RIDGE POKING INTO EASTERN
PENNSYLVANIA AND NORTHERN NEW JERSEY DURING ROUGHLY THE SAME TIME.
STORM TOTAL RAINFALL AMOUNTS OF 2 TO 3.5 INCHES OF RAIN ARE
EXPECTED. THE INITIAL SHOT OF HEAVY RAIN AFFECTS SOUTHERN AREAS
DURING THE AFTERNOON. RAINFALL AMOUNTS IN THIS SHOT COULD APPROACH
2.5 INCHES ACROSS PORTIONS OF NORTHERN DELAWARE AND SOUTHEAST
PENNSYLVANIA. THESE QPF NUMBERS PUSH SOME OF THE FLASHIER STREAMS
AND SMALL RIVERS (SUCH AS THE CHRISTINA) ABOVE THEIR BANKS.
THIS IS THE REASON NORTHERN DELAWARE AND MUCH OF SOUTHEAST
PENNSYLVANIA WERE INCLUDED IN THE WATCH.
FARTHER NORTH...WHERE THE RICH THETA RICH AIR PUSHES IN DURING
THE LATE AFTERNOON AND EARLY EVENING...HIGHER QPF VALUES ARE
EXPECTED. IN THESE AREAS...STORM TOTAL RAINFALL VALUES CLOSE TO
3.5 INCHES ARE POSSIBLE IN PLACES IN MORRIS COUNTY. WHILE THIS
MUCH RAIN DOES NOT RESULT IN MAINSTEM RIVER FLOODING...SMALLER
RIVERS AND STREAMS (SUCH AS THOSE IN MORRIS COUNTY) SHOULD RESPOND
QUICKLY TO THESE AMOUNTS. IF CLOSER TO 4 INCHES OF RAIN FALLS IN
THE PASSAIC BASIN...MAINSTEM FLOODING COULD BECOME POSSIBLE.
THE HEAVIEST RAIN TAPERS OFF FROM SOUTHWEST TO NORTHEAST LATE SUNDAY
EVENING INTO EARLY MONDAY MORNING. THE FLOOD WATCH WAS EXTENDED
THROUGH MUCH OF THE NIGHT TO ALLOW FOR THE RAINFALL TO WORK ITS WAY
THROUGH THE SYSTEM.
RUNNING SOME CONTINGENT FORECASTS AND USING SOME MMEFS DATA, THESE
ARE SOME NUMBERS TO WATCH FOR (BASIN-WIDE AVERAGES) FOR POTENTIAL
FLOODING...
QUICK RESPONDERS ACROSS SE PA AND NRN DE...2.25 TO 2.50"
SLOWER RESPONDERS ACROSS SE PA...3.00"
RANCOCAS BASIN...3.00"
RARITAN BASIN...3.75"
PASSAIC BASIN...4.00"
LEHIGH BASIN...4.00+"
POCONOS...4.00+"
&&
.TIDES/COASTAL FLOODING...
WE WILL ISSUE A COASTAL FLOOD ADVISORY FOR THE OCEAN, DELAWARE BAY
AND TIDAL SECTIONS OF THE DELAWARE RIVER FOR TONIGHT`S HIGH TIDE
CYCLE. WHILE THE SURGE GUIDANCE HAS OUR AREA JUST GETTING OR
FALLING A BIT SHORT OF THE NEEDED CRITERIA, OUR LOCAL STUDY PROGRAM
TAKES TIDAL DEPARTURES HALFWAY INTO THE MINOR TIDAL FLOODING
CRITERIA SOUTH WITH LESS DEPARTURES FARTHER NORTH. SO LEAST
CONFIDENCE UP TOWARD NYC, WILL DEPEND UPON HOW QUICKLY WINDS
INCREASE LEADING INTO THE HIGH TIDE CYCLE. THE ADDED COMPLICATION
WILL BE THAT HEAVY RAIN WILL BE ONGOING DURING THE HIGH TIDE CYCLE.
WE ARE GOING TO HOLD OFF ON CHESAPEAKE BAY AS THE HIGHER
ASTRONOMICAL TIDE IS DURING THE DAY ON MONDAY. THE CBOFS
GUIDANCE IS FORECASTING MINOR TIDAL FLOODING, BUT IT TENDS TO RUN A
BIT TOO HIGH.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FLOOD WATCH THROUGH LATE TONIGHT FOR PAZ067>071.
COASTAL FLOOD ADVISORY FROM MIDNIGHT TONIGHT TO 5 AM EDT
MONDAY FOR PAZ070-071.
NJ...FLOOD WATCH THROUGH LATE TONIGHT FOR NJZ008>010-012-015.
WIND ADVISORY FROM 4 PM THIS AFTERNOON TO 4 AM EDT MONDAY FOR
NJZ012>027.
COASTAL FLOOD ADVISORY FROM 8 PM THIS EVENING TO MIDNIGHT EDT
TONIGHT FOR NJZ012>014-020-022>027.
COASTAL FLOOD ADVISORY FROM MIDNIGHT TONIGHT TO 5 AM EDT
MONDAY FOR NJZ016>019-021.
DE...FLOOD WATCH THROUGH LATE TONIGHT FOR DEZ001.
WIND ADVISORY FROM 4 PM THIS AFTERNOON TO 4 AM EDT MONDAY FOR
DEZ001>004.
COASTAL FLOOD ADVISORY FROM 8 PM THIS EVENING TO MIDNIGHT EDT
TONIGHT FOR DEZ003-004.
COASTAL FLOOD ADVISORY FROM MIDNIGHT TONIGHT TO 5 AM EDT
MONDAY FOR DEZ001-002.
MD...NONE.
MARINE...GALE WARNING FROM 5 PM THIS AFTERNOON TO 2 AM EDT MONDAY FOR
ANZ430-431-452>455.
GALE WARNING FROM 5 PM THIS AFTERNOON TO 5 AM EDT MONDAY FOR
ANZ450-451.
&&
$$
SYNOPSIS...GIGI/HAYES
NEAR TERM...HAYES
SHORT TERM...O`HARA
LONG TERM...GIGI/HAYES
AVIATION...GIGI/HAYES/O`HARA
MARINE...HAYES/O`HARA
HYDROLOGY...GIGI
TIDES/COASTAL FLOODING...GIGI
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
1129 PM EDT MON APR 23 2012
.UPDATE...
QUICK UPDATE HAS BEEN ISSUED TO REMOVE EXPIRING HEADLINES FROM
FORECAST PRODUCTS. NO OTHER CHANGES WERE NECESSARY.
&&
.PREV DISCUSSION... /ISSUED 920 PM EDT MON APR 23 2012/
SHORT TERM (TONIGHT-TUESDAY)...
24/00Z WATER VAPOR AND H4 RUC ANALYSIS SHOWING A HIGHLY AMPLIFIED
UPPER LEVEL PATTERN OVER THE CONUS THIS EVENING. NORTHERN STREAM
FLOW RIDGES OFF THE PACIFIC OVER THE CANADIAN ROCKIES BEFORE DIVING
BACK INTO IMPRESSIVE LONGWAVE TROUGHING OVER THE EASTERN HALF OF THE
CONTINENT. THIS UPPER TROUGH IS ANCHORED BY A DEEP 525DM CLOSED LOW
CENTERED OVER WESTERN NEW YORK. WITH SUCH A DEEP/COLD LOW...IT IS NO
WONDER THAT A LATE SEASON SNOWSTORM IS UNDERWAY FROM WESTERN
PENNSYLVANIA TO WESTERN NEW YORK. THE UNUSUAL LATE APRIL WEATHER IS
NOT CONFINED TO THE NORTHEASTERN STATES. THE STRENGTH OF THE
LONGWAVE TROUGH IS RESULTING IN H5 HEIGHTS THAT ARE 3-4 STANDARD
DEVIATIONS BELOW CLIMATOLOGY ACROSS NORTHERN FLORIDA THIS EVENING.
A BIT LOWER IN THE COLUMN...THE 850MB TEMPS OVER THE FORECAST AREA
ARE CURRENTLY AROUND 3 STANDARD DEVIATIONS BELOW CLIMATOLOGY. HOW
UNUSUAL IS THIS FOR LATE APRIL?...WELL THERE IS ONLY A 4% CHANCE OF
OCCURRENCE FOR AN EVENT THAT IS 3 STANDARD DEVIATIONS FROM THE
CLIMATOLOGICAL MEAN...AND ONLY AROUND A 0.2% CHANCE OF OCCURRENCE
ONCE YOU REACH 4 STANDARD DEVIATIONS. WV ALSO SHOWS A VERY DRY
ATMOSPHERE OVERHEAD IN THE MIDDLE AND UPPER LEVELS...AND THIS IS
CONFIRMED BY THE 24/00Z KTBW SOUNDING PROFILE. THE CALCULATED PW
VALUES IS ONLY AROUND 0.53"...WHICH IS ABOUT HALF OF CLIMATOLOGY.
AT THE SURFACE...STILL LOOKING AT A RATHER TIGHT PRESSURE GRADIENT
OVER THE REGION BETWEEN STRONG SUB 990MB LOW PRESSURE OVER NEW
YORK...AND HIGH PRESSURE BEGINNING TO BUILD EASTWARD ALONG THE
NORTHERN GULF COAST. THIS GRADIENT WILL BEGIN TO RELAX OVER THE NEXT
12-24 HOURS AS THE HIGH CENTER EDGES CLOSER ACROSS THE GULF.
THE BIG STORY OVERNIGHT WILL BE THE COOL LOW TEMPERATURES. THE DRY
LOWER LEVELS AND DIMINISHING WINDS WILL ALLOW TEMPS TO STEADILY
FALL. THE COLDEST TEMPERATURES WILL NOT OCCUR UNTIL AROUND SUNRISE
WITH MANY INLAND LOCATIONS DROPPING INTO THE 40S. NOT OUT OF THE
QUESTION THAT NORMALLY COLDER INLAND SPOTS ACROSS THE NORTHERN
FORECAST AREA (LEVY/CITRUS COUNTIES)...AND ALSO THE NORMALLY COLDER
SPOTS IN HIGHLANDS COUNTY COULD BRIEFLY DIP INTO THE UPPER 30S. WITH
WINDS NOT EXPECTED TO COMPLETELY DIE OFF OVERNIGHT...WE ARE LIKELY
TO NOT COMPLETELY DECOUPLE. WITH THIS IN MIND...NOT ANTICIPATING A
FROST THREAT...HOWEVER TEMPERATURES WILL NEED TO MONITORED CLOSELY
IN THESE AREAS.
TUESDAY...UPPER TROUGH WILL BEGIN TO PULL AWAY FROM THE REGION
ALLOWING HEIGHT RISES AND A SLOW 850MB TEMP RECOVERY. STILL WILL BE
DEALING WITH HIGH TEMPERATURES WHICH ARE BELOW NORMAL IN THE
70S...HOWEVER AFTER ANOTHER COOL NIGHT TUESDAY...NOTICEABLY WARMER
READINGS WILL RETURN TO THE FORECAST FOR WEDNESDAY. HAVE A GREAT
EVENING AND STAY WARM.
AVIATION...
VFR CONDITIONS WITH GUSTY WEST TO NORTHWEST WINDS DIMINISHING
AND BECOMING MORE NORTHERLY OVERNIGHT. WINDS WILL BACK TO
NORTHWEST AGAIN TUESDAY AFTERNOON.
MARINE...
STRONG GUSTY WINDS WITH WAVE HEIGHTS UPWARDS OF 7 FEET WILL MAKE
FOR HAZARDOUS MARINE CONDITIONS INTO TUESDAY. WINDS AND SEAS WILL
DIMINISH AFTER TUESDAY AFTERNOON AS THE HIGH BUILDS SOUTHWARD AND
THE PRESSURE GRADIENT RELAXES.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 54 72 53 81 / 0 0 0 0
FMY 57 77 52 83 / 0 0 0 0
GIF 47 72 46 83 / 0 0 0 0
SRQ 57 72 52 77 / 0 0 0 0
BKV 43 72 41 81 / 0 0 0 0
SPG 59 72 58 79 / 0 0 0 0
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY
EVENING FOR CHARLOTTE-CITRUS-DE SOTO-HARDEE-HERNANDO-
HIGHLANDS-HILLSBOROUGH-LEE-LEVY-MANATEE-PASCO-
PINELLAS-POLK-SARASOTA-SUMTER.
GULF WATERS...SMALL CRAFT ADVISORY UNTIL 11 AM EDT TUESDAY FOR BONITA
BEACH TO ENGLEWOOD OUT 20 TO 60 NM-ENGLEWOOD TO
TARPON SPRINGS OUT 20 TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 6 AM EDT TUESDAY FOR BONITA
BEACH TO ENGLEWOOD OUT 20 NM-ENGLEWOOD TO TARPON
SPRINGS OUT 20 NM-TARPON SPRINGS TO SUWANNEE RIVER
OUT 20 NM-TARPON SPRINGS TO SUWANNEE RIVER OUT 20 TO
60 NM.
&&
$$
SHORT TERM/MARINE/FIRE WEATHER...21/JELSEMA
LONG TERM/AVIATION...22/REYNES
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
920 PM EDT MON APR 23 2012
.SHORT TERM (TONIGHT-TUESDAY)...
24/00Z WATER VAPOR AND H4 RUC ANALYSIS SHOWING A HIGHLY AMPLIFIED
UPPER LEVEL PATTERN OVER THE CONUS THIS EVENING. NORTHERN STREAM
FLOW RIDGES OFF THE PACIFIC OVER THE CANADIAN ROCKIES BEFORE DIVING
BACK INTO IMPRESSIVE LONGWAVE TROUGHING OVER THE EASTERN HALF OF THE
CONTINENT. THIS UPPER TROUGH IS ANCHORED BY A DEEP 525DM CLOSED LOW
CENTERED OVER WESTERN NEW YORK. WITH SUCH A DEEP/COLD LOW...IT IS NO
WONDER THAT A LATE SEASON SNOWSTORM IS UNDERWAY FROM WESTERN
PENNSYLVANIA TO WESTERN NEW YORK. THE UNUSUAL LATE APRIL WEATHER IS
NOT CONFINED TO THE NORTHEASTERN STATES. THE STRENGTH OF THE
LONGWAVE TROUGH IS RESULTING IN H5 HEIGHTS THAT ARE 3-4 STANDARD
DEVIATIONS BELOW CLIMATOLOGY ACROSS NORTHERN FLORIDA THIS EVENING.
A BIT LOWER IN THE COLUMN...THE 850MB TEMPS OVER THE FORECAST AREA
ARE CURRENTLY AROUND 3 STANDARD DEVIATIONS BELOW CLIMATOLOGY. HOW
UNUSUAL IS THIS FOR LATE APRIL?...WELL THERE IS ONLY A 4% CHANCE OF
OCCURRENCE FOR AN EVENT THAT IS 3 STANDARD DEVIATIONS FROM THE
CLIMATOLOGICAL MEAN...AND ONLY AROUND A 0.2% CHANCE OF OCCURRENCE
ONCE YOU REACH 4 STANDARD DEVIATIONS. WV ALSO SHOWS A VERY DRY
ATMOSPHERE OVERHEAD IN THE MIDDLE AND UPPER LEVELS...AND THIS IS
CONFIRMED BY THE 24/00Z KTBW SOUNDING PROFILE. THE CALCULATED PW
VALUES IS ONLY AROUND 0.53"...WHICH IS ABOUT HALF OF CLIMATOLOGY.
AT THE SURFACE...STILL LOOKING AT A RATHER TIGHT PRESSURE GRADIENT
OVER THE REGION BETWEEN STRONG SUB 990MB LOW PRESSURE OVER NEW
YORK...AND HIGH PRESSURE BEGINNING TO BUILD EASTWARD ALONG THE
NORTHERN GULF COAST. THIS GRADIENT WILL BEGIN TO RELAX OVER THE NEXT
12-24 HOURS AS THE HIGH CENTER EDGES CLOSER ACROSS THE GULF.
THE BIG STORY OVERNIGHT WILL BE THE COOL LOW TEMPERATURES. THE DRY
LOWER LEVELS AND DIMINISHING WINDS WILL ALLOW TEMPS TO STEADILY
FALL. THE COLDEST TEMPERATURES WILL NOT OCCUR UNTIL AROUND SUNRISE
WITH MANY INLAND LOCATIONS DROPPING INTO THE 40S. NOT OUT OF THE
QUESTION THAT NORMALLY COLDER INLAND SPOTS ACROSS THE NORTHERN
FORECAST AREA (LEVY/CITRUS COUNTIES)...AND ALSO THE NORMALLY COLDER
SPOTS IN HIGHLANDS COUNTY COULD BRIEFLY DIP INTO THE UPPER 30S. WITH
WINDS NOT EXPECTED TO COMPLETELY DIE OFF OVERNIGHT...WE ARE LIKELY
TO NOT COMPLETELY DECOUPLE. WITH THIS IN MIND...NOT ANTICIPATING A
FROST THREAT...HOWEVER TEMPERATURES WILL NEED TO MONITORED CLOSELY
IN THESE AREAS.
TUESDAY...UPPER TROUGH WILL BEGIN TO PULL AWAY FROM THE REGION
ALLOWING HEIGHT RISES AND A SLOW 850MB TEMP RECOVERY. STILL WILL BE
DEALING WITH HIGH TEMPERATURES WHICH ARE BELOW NORMAL IN THE
70S...HOWEVER AFTER ANOTHER COOL NIGHT TUESDAY...NOTICEABLY WARMER
READINGS WILL RETURN TO THE FORECAST FOR WEDNESDAY. HAVE A GREAT
EVENING AND STAY WARM.
&&
.AVIATION...
VFR CONDITIONS WITH GUSTY WEST TO NORTHWEST WINDS DIMINISHING
AND BECOMING MORE NORTHERLY OVERNIGHT. WINDS WILL BACK TO
NORTHWEST AGAIN TUESDAY AFTERNOON.
&&
.MARINE...
STRONG GUSTY WINDS WITH WAVE HEIGHTS UPWARDS OF 7 FEET WILL MAKE
FOR HAZARDOUS MARINE CONDITIONS INTO TUESDAY. WINDS AND SEAS WILL
DIMINISH AFTER TUESDAY AFTERNOON AS THE HIGH BUILDS SOUTHWARD AND
THE PRESSURE GRADIENT RELAXES.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 54 72 53 81 / 0 0 0 0
FMY 56 77 51 83 / 0 0 0 0
GIF 47 72 46 83 / 0 0 0 0
SRQ 56 72 51 79 / 0 0 0 0
BKV 43 72 41 81 / 0 0 0 0
SPG 58 72 57 79 / 0 0 0 0
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY
EVENING FOR CHARLOTTE-CITRUS-DE SOTO-HARDEE-HERNANDO-
HIGHLANDS-HILLSBOROUGH-LEE-LEVY-MANATEE-PASCO-
PINELLAS-POLK-SARASOTA-SUMTER.
HIGH SURF ADVISORY UNTIL 11 PM EDT THIS EVENING FOR
CHARLOTTE-CITRUS-HERNANDO-HILLSBOROUGH-LEE-LEVY-
MANATEE-PASCO-PINELLAS-SARASOTA.
GULF WATERS...SMALL CRAFT ADVISORY UNTIL 6 AM EDT TUESDAY FOR BONITA
BEACH TO ENGLEWOOD OUT 20 NM-ENGLEWOOD TO TARPON
SPRINGS OUT 20 NM-TARPON SPRINGS TO SUWANNEE RIVER
OUT 20 NM-TARPON SPRINGS TO SUWANNEE RIVER OUT 20 TO
60 NM.
SMALL CRAFT ADVISORY UNTIL 11 AM EDT TUESDAY FOR BONITA
BEACH TO ENGLEWOOD OUT 20 TO 60 NM-ENGLEWOOD TO
TARPON SPRINGS OUT 20 TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR
TAMPA BAY WATERS.
&&
$$
UPDATE...14/MROCZKA
AVIATION...63/JILLSON
AREA FORECAST DISCUSSION
NWS MIAMI FL
649 PM EDT SUN APR 22 2012
.UPDATE...WINDS HAVE SUBSIDED SO THE WIND ADVISORY WAS CANCELLED.
JUST A FEW SMALL SHOWERS NEAR LAKE OKEECHOBEE. WILL UPDATE
FORECAST SOON TO TAKE OUT MENTION OF SHOWERS AS COOLER AND DRIER
AIR WILL CONTINUE TO MOVE INTO SOUTH FL TONIGHT. FOR ADDITIONAL
FORECAST DETAILS, SEE PREVIOUS DISCUSSION BELOW.
&&
.PREV DISCUSSION... /ISSUED 307 PM EDT SUN APR 22 2012/
DISCUSSION...
COLD FRONT MOVING THROUGH SOUTH FLORIDA THIS AFTERNOON. ALMOST ALL
SHOWERS THAT MOVED ACROSS THE REGION PRODUCED GUSTS OF 35-45
MPH...WITH ONE LONE THUNDERSTORM PRODUCING WINDS TO 54 MPH AT
KFXE. ONLY A FEW LINGERING SHOWERS WERE ACROSS THE EAST COAST
METRO AREAS AND THESE SHOULD END OVER THE NEXT HOUR OR TWO. STRONG
WESTERLY WINDS WILL CONTINUE...HOWEVER...ACROSS BROWARD...MIAMI
DADE...MAINLAND MONROE AND COASTAL COLLIER COUNTIES AND FREQUENT
GUSTS TO 40 MPH ARE EXPECTED THROUGH EARLY THIS EVENING. SO THE
WIND ADVISORY WILL REMAIN IN EFFECT THROUGH 8 PM THIS EVENING.
WATER VAPOR AND RUC ANALYSIS THIS AFTERNOON SHOWED SURFACE HIGH
PRESSURE NEAR THE NORTH CAROLINA COAST RACING OFF TO THE
NORTHEAST. AN UPPER LEVEL TROUGH AND CUTOFF UPPER LOW WERE DIGGING
SOUTHEAST ACROSS KENTUCKY THIS AFTERNOON. DRIER AIR IS EXPECTED TO
BEGIN FILTERING INTO THE REGION STARTING AROUND MIDNIGHT BEHIND
THE FRONT...WITH PWATS FALLING BELOW 0.75 INCHES. BREEZY
CONDITIONS WILL CONTINUE THROUGH THE EVENING FOR MUCH OF THE
REGION AND INTO THE OVERNIGHT HOURS FOR AREAS ALONG THE COAST.
COOLER CONDITIONS ARE EXPECTED TONIGHT WITH LOWS IN THE 50S AROUND
THE LAKE TO THE LOW TO MID 60S FOR THE EAST COAST METRO AREAS.
A SECONDARY SURGE OF DRIER AND COOLER AIR IS EXPECTED ON MONDAY AS
THE STRONG TROUGH OF LOW PRESSURE DIGS INTO THE SOUTHEAST AND
FLORIDA. THIS WILL INCREASE THE WINDS ACROSS THE REGION MONDAY
AFTERNOON...AND BREEZY TO WINDY CONDITIONS CAN BE EXPECTED...
ESPECIALLY TOWARDS THE GULF COAST. TEMPERATURES ON MONDAY WILL
RISE INTO THE UPPER 70S TO LOWER 80S.
MUCH COOLER AND EVEN DRIER AIR WILL BEGIN TO FILTER INTO THE
REGION...WITH PWATS FALLING BELOW 0.5 INCHES BY TUESDAY MORNING.
LOWS AND HIGHS TUESDAY THROUGH WEDNESDAY ARE EXPECTED TO BE 7-12
DEGREES BELOW NORMAL. 1000-850MB THICKNESS VALUES TUESDAY MORNING
ARE EXPECTED TO BE AROUND 1340M. SO TEMPERATURES MAY FALL INTO THE
MID/UPPER 40S NEAR THE LAKE...NEAR 50 ACROSS THE REST OF THE
INTERIOR...AND 50S TO AROUND 60 FOR THE EAST COAST METRO AREAS.
HIGHS ON TUESDAY ARE EXPECTED TO ONLY GET INTO THE LOW TO MID 70S
ACROSS THE REGION. FOR WEDNESDAY MORNING...ALTHOUGH THICKNESS
VALUES WILL INCREASE...DEWPOINTS TUESDAY AFTERNOON ARE EXPECTED TO
DROP INTO THE 30S ACROSS THE REGION. HIGH PRESSURE IS ALSO
EXPECTED TO MOVE DIRECTLY OVERHEAD. SO WITH LIGHT WINDS AND
EXCELLENT RADIATIONAL COOLING...TEMPERATURES WILL GET NEAR THE
SAME OR EVEN COLDER THAN TUESDAY MORNING.
SURFACE HIGH PRESSURE WILL REMAIN IN CONTROL OF THE WEATHER
THROUGH THE END OF THE WEEK. TEMPERATURES ARE EXPECTED TO SLOWLY
REBOUND TO NEAR NORMAL.
AVIATION...
SHOWERS STILL LINGER OVER EASTERN PORTIONS OF THE
REGION AS A COLD FRONT PASSES. VCSH IS CARRIED FOR THE EAST COAST
TERMINALS THROUGH 20Z. BRIEF CEILING AND VISIBILITY REDUCTIONS
ARE POSSIBLE IN ANY SHRA. OTHERWISE, WIND SPEEDS REMAIN THE
PRIMARY CONCERN WITH GUSTS OF 25 TO 30 KNOTS POSSIBLE THROUGH AT
LEAST 00Z. PREVAILING VFR EXPECTED THIS EVENING AND OVERNIGHT.
MARINE...
HAZARDOUS MARINE CONDITIONS WILL CONTINUE OVER THE ATLANTIC AND
GULF WATERS THROUGH LATE TONIGHT AND START TO SUBSIDE.
HOWEVER...AS A STRONG UPPER LEVEL TROUGH DIGS INTO THE
SOUTHEAST...A SECONDARY PUSH OF STRONG NORTHWESTERLY WINDS ARE
EXPECTED ACROSS THE LOCAL WATERS LATE MONDAY MORNING THROUGH
MONDAY NIGHT.
FIRE WEATHER...
A VERY DRY AIRMASS SHOULD SPREAD SOUTH WITH RH VALUES FALLING
BELOW 35% FOR SEVERAL HOURS ACROSS A GOOD PORTION OF SOUTH
FLORIDA BY MONDAY AFTERNOON AND ACROSS ALL OF THE AREA ON TUESDAY
AND WEDNESDAY. WINDS WILL INCREASE ON MONDAY AS A SECONDARY SURGE
OF DRIER AIR MOVES ACROSS THE REGION...WITH WINDS ACROSS THE WEST
COAST EXPECTED TO BE ABOVE 15 MPH. HOWEVER...WITH THE RECENT
RAINFALL...ERC VALUES ARE EXPECTED TO REMAIN BELOW 20. SO A FIRE
WEATHER WATCH IS NOT GOING TO BE ISSUED AT THIS TIME.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 62 81 57 74 / - 0 0 0
FORT LAUDERDALE 64 83 59 76 / - 0 0 0
MIAMI 64 82 59 76 / - 0 0 0
NAPLES 64 81 57 73 / - 0 0 0
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...HIGH RIP CURRENT RISK THROUGH MONDAY MORNING FOR COASTAL COLLIER.
AM...SMALL CRAFT ADVISORY UNTIL 2 AM EDT TUESDAY FOR COASTAL WATERS
FROM DEERFIELD BEACH TO OCEAN REEF, FL OUT 20 NM-COASTAL
WATERS FROM JUPITER INLET TO DEERFIELD BEACH, FL OUT 20 NM-
WATERS FROM DEERFIELD BEACH TO OCEAN REEF, FL EXTENDING
FROM 20 NM TO THE TERRITORIAL WATERS OF THE BAHAMAS-WATERS
FROM JUPITER INLET TO DEERFIELD BEACH, FL EXTENDING FROM 20
NM TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 6 AM EDT MONDAY FOR BISCAYNE BAY.
SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LAKE
OKEECHOBEE.
GM...SMALL CRAFT ADVISORY UNTIL 2 AM EDT TUESDAY FOR COASTAL WATERS
FROM CHOKOLOSKEE TO BONITA BEACH, FL OUT 20 NM-COASTAL
WATERS FROM EAST CAPE SABLE TO CHOKOLOSKEE, FL OUT 20 NM-
GULF WATERS FROM CHOKOLOSKEE TO BONITA BEACH, FL EXTENDING
FROM 20 TO 60 NM.
&&
$$
AREA FORECAST DISCUSSION
NWS MIAMI FL
307 PM EDT SUN APR 22 2012
.DISCUSSION...
COLD FRONT MOVING THROUGH SOUTH FLORIDA THIS AFTERNOON. ALMOST ALL
SHOWERS THAT MOVED ACROSS THE REGION PRODUCED GUSTS OF 35-45
MPH...WITH ONE LONE THUNDERSTORM PRODUCING WINDS TO 54 MPH AT
KFXE. ONLY A FEW LINGERING SHOWERS WERE ACROSS THE EAST COAST
METRO AREAS AND THESE SHOULD END OVER THE NEXT HOUR OR TWO. STRONG
WESTERLY WINDS WILL CONTINUE...HOWEVER...ACROSS BROWARD...MIAMI
DADE...MAINLAND MONROE AND COASTAL COLLIER COUNTIES AND FREQUENT
GUSTS TO 40 MPH ARE EXPECTED THROUGH EARLY THIS EVENING. SO THE
WIND ADVISORY WILL REMAIN IN EFFECT THROUGH 8 PM THIS EVENING.
WATER VAPOR AND RUC ANALYSIS THIS AFTERNOON SHOWED SURFACE HIGH
PRESSURE NEAR THE NORTH CAROLINA COAST RACING OFF TO THE
NORTHEAST. AN UPPER LEVEL TROUGH AND CUTOFF UPPER LOW WERE DIGGING
SOUTHEAST ACROSS KENTUCKY THIS AFTERNOON. DRIER AIR IS EXPECTED TO
BEGIN FILTERING INTO THE REGION STARTING AROUND MIDNIGHT BEHIND
THE FRONT...WITH PWATS FALLING BELOW 0.75 INCHES. BREEZY
CONDITIONS WILL CONTINUE THROUGH THE EVENING FOR MUCH OF THE
REGION AND INTO THE OVERNIGHT HOURS FOR AREAS ALONG THE COAST.
COOLER CONDITIONS ARE EXPECTED TONIGHT WITH LOWS IN THE 50S AROUND
THE LAKE TO THE LOW TO MID 60S FOR THE EAST COAST METRO AREAS.
A SECONDARY SURGE OF DRIER AND COOLER AIR IS EXPECTED ON MONDAY AS
THE STRONG TROUGH OF LOW PRESSURE DIGS INTO THE SOUTHEAST AND
FLORIDA. THIS WILL INCREASE THE WINDS ACROSS THE REGION MONDAY
AFTERNOON...AND BREEZY TO WINDY CONDITIONS CAN BE EXPECTED...
ESPECIALLY TOWARDS THE GULF COAST. TEMPERATURES ON MONDAY WILL
RISE INTO THE UPPER 70S TO LOWER 80S.
MUCH COOLER AND EVEN DRIER AIR WILL BEGIN TO FILTER INTO THE
REGION...WITH PWATS FALLING BELOW 0.5 INCHES BY TUESDAY MORNING.
LOWS AND HIGHS TUESDAY THROUGH WEDNESDAY ARE EXPECTED TO BE 7-12
DEGREES BELOW NORMAL. 1000-850MB THICKNESS VALUES TUESDAY MORNING
ARE EXPECTED TO BE AROUND 1340M. SO TEMPERATURES MAY FALL INTO THE
MID/UPPER 40S NEAR THE LAKE...NEAR 50 ACROSS THE REST OF THE
INTERIOR...AND 50S TO AROUND 60 FOR THE EAST COAST METRO AREAS.
HIGHS ON TUESDAY ARE EXPECTED TO ONLY GET INTO THE LOW TO MID 70S
ACROSS THE REGION. FOR WEDNESDAY MORNING...ALTHOUGH THICKNESS
VALUES WILL INCREASE...DEWPOINTS TUESDAY AFTERNOON ARE EXPECTED TO
DROP INTO THE 30S ACROSS THE REGION. HIGH PRESSURE IS ALSO
EXPECTED TO MOVE DIRECTLY OVERHEAD. SO WITH LIGHT WINDS AND
EXCELLENT RADIATIONAL COOLING...TEMPERATURES WILL GET NEAR THE
SAME OR EVEN COLDER THAN TUESDAY MORNING.
SURFACE HIGH PRESSURE WILL REMAIN IN CONTROL OF THE WEATHER
THROUGH THE END OF THE WEEK. TEMPERATURES ARE EXPECTED TO SLOWLY
REBOUND TO NEAR NORMAL.
&&
.AVIATION...
SHOWERS STILL LINGER OVER EASTERN PORTIONS OF THE
REGION AS A COLD FRONT PASSES. VCSH IS CARRIED FOR THE EAST COAST
TERMINALS THROUGH 20Z. BRIEF CEILING AND VISIBILITY REDUCTIONS
ARE POSSIBLE IN ANY SHRA. OTHERWISE, WIND SPEEDS REMAIN THE
PRIMARY CONCERN WITH GUSTS OF 25 TO 30 KNOTS POSSIBLE THROUGH AT
LEAST 00Z. PREVAILING VFR EXPECTED THIS EVENING AND OVERNIGHT.
&&
.MARINE...
HAZARDOUS MARINE CONDITIONS WILL CONTINUE OVER THE ATLANTIC AND
GULF WATERS THROUGH LATE TONIGHT AND START TO SUBSIDE.
HOWEVER...AS A STRONG UPPER LEVEL TROUGH DIGS INTO THE
SOUTHEAST...A SECONDARY PUSH OF STRONG NORTHWESTERLY WINDS ARE
EXPECTED ACROSS THE LOCAL WATERS LATE MONDAY MORNING THROUGH
MONDAY NIGHT.
&&
.FIRE WEATHER...
A VERY DRY AIRMASS SHOULD SPREAD SOUTH WITH RH VALUES FALLING
BELOW 35% FOR SEVERAL HOURS ACROSS A GOOD PORTION OF SOUTH
FLORIDA BY MONDAY AFTERNOON AND ACROSS ALL OF THE AREA ON TUESDAY
AND WEDNESDAY. WINDS WILL INCREASE ON MONDAY AS A SECONDARY SURGE
OF DRIER AIR MOVES ACROSS THE REGION...WITH WINDS ACROSS THE WEST
COAST EXPECTED TO BE ABOVE 15 MPH. HOWEVER...WITH THE RECENT
RAINFALL...ERC VALUES ARE EXPECTED TO REMAIN BELOW 20. SO A FIRE
WEATHER WATCH IS NOT GOING TO BE ISSUED AT THIS TIME.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 62 81 57 74 / - 0 0 0
FORT LAUDERDALE 64 83 59 76 / - 0 0 0
MIAMI 64 82 59 76 / - 0 0 0
NAPLES 64 81 57 73 / - 0 0 0
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...WIND ADVISORY UNTIL 8 PM EDT THIS EVENING FOR COASTAL BROWARD-
COASTAL COLLIER-COASTAL MIAMI DADE-FAR SOUTH MIAMI DADE-
INLAND MIAMI DADE-MAINLAND MONROE-METRO BROWARD-METRO MIAMI
DADE.
HIGH RIP CURRENT RISK THROUGH MONDAY MORNING FOR COASTAL COLLIER.
AM...SMALL CRAFT ADVISORY UNTIL 2 AM EDT TUESDAY FOR COASTAL WATERS
FROM DEERFIELD BEACH TO OCEAN REEF, FL OUT 20 NM-COASTAL
WATERS FROM JUPITER INLET TO DEERFIELD BEACH, FL OUT 20 NM.
SMALL CRAFT ADVISORY UNTIL 5 AM EDT MONDAY FOR WATERS FROM
DEERFIELD BEACH TO OCEAN REEF, FL EXTENDING FROM 20 NM TO
THE TERRITORIAL WATERS OF THE BAHAMAS.
SMALL CRAFT ADVISORY UNTIL 6 AM EDT MONDAY FOR BISCAYNE BAY.
SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR WATERS
FROM JUPITER INLET TO DEERFIELD BEACH, FL EXTENDING FROM 20
NM TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LAKE
OKEECHOBEE.
GM...SMALL CRAFT ADVISORY UNTIL 2 AM EDT TUESDAY FOR COASTAL WATERS
FROM CHOKOLOSKEE TO BONITA BEACH, FL OUT 20 NM-GULF WATERS
FROM CHOKOLOSKEE TO BONITA BEACH, FL EXTENDING FROM 20 TO
60 NM.
SMALL CRAFT ADVISORY UNTIL 5 AM EDT MONDAY FOR COASTAL WATERS
FROM EAST CAPE SABLE TO CHOKOLOSKEE, FL OUT 20 NM.
&&
$$
DISCUSSION/MARINE/FIRE...84/AK
AVIATION/RADAR...14/MJB
AREA FORECAST DISCUSSION
NWS MIAMI FL
230 PM EDT SUN APR 22 2012
.AVIATION...SHOWERS STILL LINGER OVER EASTERN PORTIONS OF THE
REGION AS A COLD FRONT PASSES. VCSH IS CARRIED FOR THE EAST COAST
TERMINALS THROUGH 20Z. BRIEF CEILING AND VISIBILITY REDUCTIONS
ARE POSSIBLE IN ANY SHRA. OTHERWISE, WIND SPEEDS REMAIN THE
PRIMARY CONCERN WITH GUSTS OF 25 TO 30 KNOTS POSSIBLE THROUGH AT
LEAST 00Z. PREVAILING VFR EXPECTED THIS EVENING AND OVERNIGHT.
&&
.PREV DISCUSSION... /ISSUED 950 AM EDT SUN APR 22 2012/
UPDATE...
THE 12Z SOUNDING THIS MORNING SHOWED 110 KT UPPER JET STREAK OVER
THE REGION...BUT DRIER AND WARMER AIR ALOFT AND COOLER AIR IN THE
LOW LEVELS. WINDS AROUND 1 KFT WERE 30 KNOTS...SO THE LEFTOVER
SHOWERS THIS MORNING COULD PRODUCE SOME WINDS AROUND 40 MPH. AN
ISOLATED THUNDERSTORM IS POSSIBLE THIS MORNING BUT EXPECT MAINLY
ISOLATED TO SCATTERED SHOWERS BEFORE THE FRONT MOVES THROUGH.
VISIBLE SATELLITE THIS MORNING SHOWED STABLY STRATIFIED AIR OVER
THE NORTHERN GULF. THE SQUALL LINE THAT MOVED ACROSS SOUTH
FLORIDA EARLY THIS MORNING HAD MOVED ACROSS THE BAHAMAS. WATER
VAPOR IMAGERY AND RUC ANALYSIS SHOWED THE UPPER LOW OVER THE
EASTERN GULF AND NORTH FLORIDA LIFTING OUT TO THE NORTHEAST AND
WEAKENING AS A STRONG VORT WAS DIVING DOWN ACROSS THE MIDWEST.
SURFACE LOW PRESSURE OVER THE FAR WESTERN ATLANTIC IS EXPECTED TO
ACCELERATE TO THE NORTHEAST AND BE OFF THE NORTHEAST COAST BY
TONIGHT.
SURFACE ANALYSIS THIS MORNING SHOWED THAT THE COLD FRONT WAS
STILL HANGING BACK OVER THE EASTERN GULF THIS MORNING...JUST TO
THE WEST OF THE NAPLES AREA. THIS FRONT IS EXPECTED TO MOVE
THROUGH THE REGION TODAY...WITH WINDY CONDITIONS THIS AFTERNOON.
GUSTS UP TO 40 MPH ARE POSSIBLE ACROSS BROWARD...MIAMI
DADE...MAINLAND MONROE AND COASTAL COLLIER COUNTY BEHIND THE FRONT
WHERE A WIND ADVISORY IS IN EFFECT FROM 11 AM THROUGH 8 PM THIS
EVENING. WITH EXCELLENT MIXING DUE TO STRONG WESTERLY WINDS AND
WITH AT LEAST DECENT DAYTIME HEATING EXPECTED...SOME LOCATIONS
ALONG THE EAST COAST COULD REACH THE MIDDLE 80S. SO BUMPED UP
TEMPERATURES A COUPLE DEGREES FOR THE EAST COAST METROS TO 84-85
DEGREES.
THERE IS A HIGH RISK OF RIP CURRENTS AT THE GULF COAST BEACHES
TODAY DUE TO THE STRONG WESTERLY FLOW. THERE ALSO MAY BE SOME
MINOR COASTAL FLOODING ALONG THE COLLIER COUNTY COAST AT HIGH TIDE
THIS AFTERNOON AS WATER LEVELS REACH 1-2 FEET ABOVE NORMAL HIGH
TIDE. THE ONLY OTHER CHANGE TO THE GOING FORECAST WAS TO LOWER SKY
COVER THIS MORNING TO ACCOUNT FOR CURRENT CONDITIONS.
PREV DISCUSSION... /ISSUED 803 AM EDT SUN APR 22 2012/
AVIATION...A STRONG COLD FRONT WILL PASS THROUGH THE REGION THIS
MORNING. WIND SPEEDS WILL BE THE PRIMARY CONCERN WITH FREQUENT
GUSTS OF 20 TO 30 KNOTS EXPECTED AFTER 14Z. A FEW SHOWERS WILL
ALSO PROGRESS ACROSS THE AREA, PERHAPS PERSISTING INTO THE
AFTERNOON WITH VCSH ASSIGNED. BRIEF MVFR-IFR CONDITIONS POSSIBLE
IN ANY SHRA, OTHERWISE VFR. WINDS WILL GRADUALLY DECREASE THIS
EVENING, ALTHOUGH WILL REMAIN GUSTY UNTIL AT LEAST 00Z.
PREV DISCUSSION... /ISSUED 620 AM EDT SUN APR 22 2012/
SHORT TERM...
CURRENTLY (07Z)...A SQUALL LINE EXTENDING FROM LAKE OKEECHOBEE
SOUTHWEST TO MAINLAND MONROE MOVING EAST AT 35 MPH. LOCAL
ESTIMATES HAVE THIS LINE REACHING PALM BEACH BEFORE 5 AM AND METRO
AREAS OF BROWARD AND MIAMI-DADE COUNTIES RIGHT ABOUT 5 AM THIS
MORNING. SEVERAL ELEMENTS ALONG THIS LINE SHOW BROAD AND WEAK
CIRCULATION SIGNATURES, BUT MAINLY RADAR ESTIMATES OF 40-50 MPH. A
TORNADO WATCH REMAINS IN EFFECT FOR ALL OF SOUTH FLORIDA AT LEAST
THROUGH 7 AM. AT THAT TIME THE LINE IS EXPECTED TO HAVE MOVE OVER
THE NEAR SHORE ATLANTIC WATERS.
TODAY THROUGH TUESDAY...VIGOROUS SHORT WAVE TROUGH AND ASSOCIATED
SFC LOW/COLD FRONT SHOULD MOVE RAPIDLY EASTWARD AND BE EAST OF THE
PENINSULA BY THIS EVENING WITH SIGNIFICANTLY DRY CONDITIONS BEHIND
IT. A RATHER TIGHT PRESS GRADIENT SHOULD DEVELOP BETWEEN THE SFC
LOW AND A RIDGE BUILDING OVER THE GOM RESULTING IN VERY WINDY
CONDITIONS ACROSS S. FLA THIS AFTERNOON. SOME PORTIONS OF S.
FLA...NAMELY COASTAL COLLIER, MAINLAND MONROE AND METRO AREAS OF
MIAMI-DADE AND BROWARD COULD SEE WIND GUSTS TO 35 MPH OR HIGHER
FROM MID-MORNING THROUGH THIS AFTERNOON. BASED ON THIS...DECIDED TO
ISSUED A WIND ADVISORY FOR THOSE AREAS FROM 15Z TO 24Z TODAY.
THE GULF OF MEX RIDGE SHOULD CONTINUE TO BUILD EAST THROUGH THE
EARLY PART OF NEXT WEEK WITH DRY CONDITIONS CONTINUING. A COOL
AIRMASS SHOULD ALSO SPREAD SOUTH ACROSS THE AREA WITH BOTH MIN/MAX
TEMPS A GOOD 7 TO 10 DEGREES BELOW SEASONAL VALUES.
A STRONG WESTERLY FLOW WILL ALSO RESULT IN VERY ROUGH SURF
CONDITIONS AND HIGH RISK OF RIP CURRENTS ALONG THE SOUTHWEST COAST
BEACHES TODAY.
LONG TERM...WEDNESDAY THROUGH SATURDAY...A DEEP LAYER RIDGE WILL
REMAIN POSITIONED OVER THE REGION KEEPING ANY SIGNIFICANT FEATURE
FROM APPROACHING THE LOCAL AREA AND DRY CONDITIONS PREVAILING
THROUGH THIS PERIOD. ALTHOUGH MILD AND PLEASANT CONDITIONS ARE
EXPECTED WITH SLIGHTLY COOLER THAN SEASONAL TEMPS, A GRADUAL
WARMING TREND SHOULD BEGIN BY MID WEEK WITH MAX AFTERNOON
TEMPS REACHING THE MID 80S BY THE WEEKEND.
MARINE...TIGHTENING OF THE PRESSURE GRADIENT BEHIND THE SFC
LOW/CD FRONT WILL KEEP SFC WINDS WELL ABOVE ADVISORY CRITERIA
ACROSS ALL LOCAL WATERS AT LEAST TONIGHT WITH A GRADUAL
IMPROVEMENT BY MONDAY MORNING.
FIRE WEATHER...A VERY DRY AIRMASS SHOULD SPREAD SOUTH WITH RH
VALUES POSSIBLY FALLING BELOW 35% ACROSS A GOOD PORTION OF SOUTH
FLORIDA BY MONDAY AFTERNOON AND ACROSS ALL OF THE AREA BY TUESDAY.
AT THIS TIME...A FIRE WEATHER WATCH IS NOT BEING CONTEMPLATED AT
THIS TIME...HOWEVER IF THIS TREND CONTINUES A WATCH COULD BE
ISSUED IN FURTHER FORECAST ISSUANCE.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 62 81 57 74 / - 0 0 0
FORT LAUDERDALE 64 83 59 76 / - 0 0 0
MIAMI 64 82 59 76 / - 0 0 0
NAPLES 64 81 57 73 / - 0 0 0
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...WIND ADVISORY UNTIL 8 PM EDT THIS EVENING FOR COASTAL BROWARD-
COASTAL COLLIER-COASTAL MIAMI DADE-FAR SOUTH MIAMI DADE-
INLAND MIAMI DADE-MAINLAND MONROE-METRO BROWARD-METRO MIAMI
DADE.
HIGH RIP CURRENT RISK THROUGH MONDAY MORNING FOR COASTAL COLLIER.
AM...SMALL CRAFT ADVISORY UNTIL 11 AM EDT MONDAY FOR BISCAYNE BAY-
COASTAL WATERS FROM DEERFIELD BEACH TO OCEAN REEF, FL OUT
20 NM-COASTAL WATERS FROM JUPITER INLET TO DEERFIELD BEACH,
FL OUT 20 NM-WATERS FROM DEERFIELD BEACH TO OCEAN REEF, FL
EXTENDING FROM 20 NM TO THE TERRITORIAL WATERS OF THE
BAHAMAS-WATERS FROM JUPITER INLET TO DEERFIELD BEACH, FL
EXTENDING FROM 20 NM TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LAKE
OKEECHOBEE.
GM...SMALL CRAFT ADVISORY UNTIL 11 AM EDT MONDAY FOR COASTAL WATERS
FROM CHOKOLOSKEE TO BONITA BEACH, FL OUT 20 NM-COASTAL
WATERS FROM EAST CAPE SABLE TO CHOKOLOSKEE, FL OUT 20 NM-
GULF WATERS FROM CHOKOLOSKEE TO BONITA BEACH, FL EXTENDING
FROM 20 TO 60 NM.
&&
$$
AVIATION...14/MJB
AREA FORECAST DISCUSSION
NWS MIAMI FL
950 AM EDT SUN APR 22 2012
.UPDATE...
THE 12Z SOUNDING THIS MORNING SHOWED 110 KT UPPER JET STREAK OVER
THE REGION...BUT DRIER AND WARMER AIR ALOFT AND COOLER AIR IN THE
LOW LEVELS. WINDS AROUND 1 KFT WERE 30 KNOTS...SO THE LEFTOVER
SHOWERS THIS MORNING COULD PRODUCE SOME WINDS AROUND 40 MPH. AN
ISOLATED THUNDERSTORM IS POSSIBLE THIS MORNING BUT EXPECT MAINLY
ISOLATED TO SCATTERED SHOWERS BEFORE THE FRONT MOVES THROUGH.
VISIBLE SATELLITE THIS MORNING SHOWED STABLY STRATIFIED AIR OVER
THE NORTHERN GULF. THE SQUALL LINE THAT MOVED ACROSS SOUTH
FLORIDA EARLY THIS MORNING HAD MOVED ACROSS THE BAHAMAS. WATER
VAPOR IMAGERY AND RUC ANALYSIS SHOWED THE UPPER LOW OVER THE
EASTERN GULF AND NORTH FLORIDA LIFTING OUT TO THE NORTHEAST AND
WEAKENING AS A STRONG VORT WAS DIVING DOWN ACROSS THE MIDWEST.
SURFACE LOW PRESSURE OVER THE FAR WESTERN ATLANTIC IS EXPECTED TO
ACCELERATE TO THE NORTHEAST AND BE OFF THE NORTHEAST COAST BY
TONIGHT.
SURFACE ANALYSIS THIS MORNING SHOWED THAT THE COLD FRONT WAS
STILL HANGING BACK OVER THE EASTERN GULF THIS MORNING...JUST TO
THE WEST OF THE NAPLES AREA. THIS FRONT IS EXPECTED TO MOVE
THROUGH THE REGION TODAY...WITH WINDY CONDITIONS THIS AFTERNOON.
GUSTS UP TO 40 MPH ARE POSSIBLE ACROSS BROWARD...MIAMI
DADE...MAINLAND MONROE AND COASTAL COLLIER COUNTY BEHIND THE FRONT
WHERE A WIND ADVISORY IS IN EFFECT FROM 11 AM THROUGH 8 PM THIS
EVENING. WITH EXCELLENT MIXING DUE TO STRONG WESTERLY WINDS AND
WITH AT LEAST DECENT DAYTIME HEATING EXPECTED...SOME LOCATIONS
ALONG THE EAST COAST COULD REACH THE MIDDLE 80S. SO BUMPED UP
TEMPERATURES A COUPLE DEGREES FOR THE EAST COAST METROS TO 84-85
DEGREES.
THERE IS A HIGH RISK OF RIP CURRENTS AT THE GULF COAST BEACHES
TODAY DUE TO THE STRONG WESTERLY FLOW. THERE ALSO MAY BE SOME
MINOR COASTAL FLOODING ALONG THE COLLIER COUNTY COAST AT HIGH TIDE
THIS AFTERNOON AS WATER LEVELS REACH 1-2 FEET ABOVE NORMAL HIGH
TIDE. THE ONLY OTHER CHANGE TO THE GOING FORECAST WAS TO LOWER SKY
COVER THIS MORNING TO ACCOUNT FOR CURRENT CONDITIONS.
&&
.PREV DISCUSSION... /ISSUED 803 AM EDT SUN APR 22 2012/
AVIATION...A STRONG COLD FRONT WILL PASS THROUGH THE REGION THIS
MORNING. WIND SPEEDS WILL BE THE PRIMARY CONCERN WITH FREQUENT
GUSTS OF 20 TO 30 KNOTS EXPECTED AFTER 14Z. A FEW SHOWERS WILL
ALSO PROGRESS ACROSS THE AREA, PERHAPS PERSISTING INTO THE
AFTERNOON WITH VCSH ASSIGNED. BRIEF MVFR-IFR CONDITIONS POSSIBLE
IN ANY SHRA, OTHERWISE VFR. WINDS WILL GRADUALLY DECREASE THIS
EVENING, ALTHOUGH WILL REMAIN GUSTY UNTIL AT LEAST 00Z.
PREV DISCUSSION... /ISSUED 620 AM EDT SUN APR 22 2012/
SHORT TERM...
CURRENTLY (07Z)...A SQUALL LINE EXTENDING FROM LAKE OKEECHOBEE
SOUTHWEST TO MAINLAND MONROE MOVING EAST AT 35 MPH. LOCAL
ESTIMATES HAVE THIS LINE REACHING PALM BEACH BEFORE 5 AM AND METRO
AREAS OF BROWARD AND MIAMI-DADE COUNTIES RIGHT ABOUT 5 AM THIS
MORNING. SEVERAL ELEMENTS ALONG THIS LINE SHOW BROAD AND WEAK
CIRCULATION SIGNATURES, BUT MAINLY RADAR ESTIMATES OF 40-50 MPH. A
TORNADO WATCH REMAINS IN EFFECT FOR ALL OF SOUTH FLORIDA AT LEAST
THROUGH 7 AM. AT THAT TIME THE LINE IS EXPECTED TO HAVE MOVE OVER
THE NEAR SHORE ATLANTIC WATERS.
TODAY THROUGH TUESDAY...VIGOROUS SHORT WAVE TROUGH AND ASSOCIATED
SFC LOW/COLD FRONT SHOULD MOVE RAPIDLY EASTWARD AND BE EAST OF THE
PENINSULA BY THIS EVENING WITH SIGNIFICANTLY DRY CONDITIONS BEHIND
IT. A RATHER TIGHT PRESS GRADIENT SHOULD DEVELOP BETWEEN THE SFC
LOW AND A RIDGE BUILDING OVER THE GOM RESULTING IN VERY WINDY
CONDITIONS ACROSS S. FLA THIS AFTERNOON. SOME PORTIONS OF S.
FLA...NAMELY COASTAL COLLIER, MAINLAND MONROE AND METRO AREAS OF
MIAMI-DADE AND BROWARD COULD SEE WIND GUSTS TO 35 MPH OR HIGHER
FROM MID-MORNING THROUGH THIS AFTERNOON. BASED ON THIS...DECIDED TO
ISSUED A WIND ADVISORY FOR THOSE AREAS FROM 15Z TO 24Z TODAY.
THE GULF OF MEX RIDGE SHOULD CONTINUE TO BUILD EAST THROUGH THE
EARLY PART OF NEXT WEEK WITH DRY CONDITIONS CONTINUING. A COOL
AIRMASS SHOULD ALSO SPREAD SOUTH ACROSS THE AREA WITH BOTH MIN/MAX
TEMPS A GOOD 7 TO 10 DEGREES BELOW SEASONAL VALUES.
A STRONG WESTERLY FLOW WILL ALSO RESULT IN VERY ROUGH SURF
CONDITIONS AND HIGH RISK OF RIP CURRENTS ALONG THE SOUTHWEST COAST
BEACHES TODAY.
LONG TERM...WEDNESDAY THROUGH SATURDAY...A DEEP LAYER RIDGE WILL
REMAIN POSITIONED OVER THE REGION KEEPING ANY SIGNIFICANT FEATURE
FROM APPROACHING THE LOCAL AREA AND DRY CONDITIONS PREVAILING
THROUGH THIS PERIOD. ALTHOUGH MILD AND PLEASANT CONDITIONS ARE
EXPECTED WITH SLIGHTLY COOLER THAN SEASONAL TEMPS, A GRADUAL
WARMING TREND SHOULD BEGIN BY MID WEEK WITH MAX AFTERNOON
TEMPS REACHING THE MID 80S BY THE WEEKEND.
MARINE...TIGHTENING OF THE PRESSURE GRADIENT BEHIND THE SFC
LOW/CD FRONT WILL KEEP SFC WINDS WELL ABOVE ADVISORY CRITERIA
ACROSS ALL LOCAL WATERS AT LEAST TONIGHT WITH A GRADUAL
IMPROVEMENT BY MONDAY MORNING.
FIRE WEATHER...A VERY DRY AIRMASS SHOULD SPREAD SOUTH WITH RH
VALUES POSSIBLY FALLING BELOW 35% ACROSS A GOOD PORTION OF SOUTH
FLORIDA BY MONDAY AFTERNOON AND ACROSS ALL OF THE AREA BY TUESDAY.
AT THIS TIME...A FIRE WEATHER WATCH IS NOT BEING CONTEMPLATED AT
THIS TIME...HOWEVER IF THIS TREND CONTINUES A WATCH COULD BE
ISSUED IN FURTHER FORECAST ISSUANCE.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 83 63 80 60 / 30 10 - -
FORT LAUDERDALE 83 65 81 61 / 30 10 - -
MIAMI 83 65 81 61 / 30 10 - -
NAPLES 81 65 79 60 / 30 10 - -
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...WIND ADVISORY UNTIL 8 PM EDT THIS EVENING FOR COASTAL BROWARD-
COASTAL COLLIER-COASTAL MIAMI DADE-FAR SOUTH MIAMI DADE-
INLAND MIAMI DADE-MAINLAND MONROE-METRO BROWARD-METRO MIAMI
DADE.
HIGH RIP CURRENT RISK THROUGH MONDAY MORNING FOR COASTAL COLLIER.
AM...SMALL CRAFT ADVISORY UNTIL 11 AM EDT MONDAY FOR BISCAYNE BAY-
COASTAL WATERS FROM DEERFIELD BEACH TO OCEAN REEF, FL OUT
20 NM-COASTAL WATERS FROM JUPITER INLET TO DEERFIELD BEACH,
FL OUT 20 NM-WATERS FROM DEERFIELD BEACH TO OCEAN REEF, FL
EXTENDING FROM 20 NM TO THE TERRITORIAL WATERS OF THE
BAHAMAS-WATERS FROM JUPITER INLET TO DEERFIELD BEACH, FL
EXTENDING FROM 20 NM TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LAKE
OKEECHOBEE.
GM...SMALL CRAFT ADVISORY UNTIL 11 AM EDT MONDAY FOR COASTAL WATERS
FROM CHOKOLOSKEE TO BONITA BEACH, FL OUT 20 NM-COASTAL
WATERS FROM EAST CAPE SABLE TO CHOKOLOSKEE, FL OUT 20 NM-
GULF WATERS FROM CHOKOLOSKEE TO BONITA BEACH, FL EXTENDING
FROM 20 TO 60 NM.
&&
$$
DISCUSSION/MARINE/FIRE...84/AK
AVIATION/RADAR...14/MJB
AREA FORECAST DISCUSSION...CORRECTED
NWS INDIANAPOLIS IN
116 PM EDT SUN APR 22 2012
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 248 AM EDT SUN APR 22 2012
A STRONG LOW PRESSURE SYSTEM MOVING ALONG THE EAST COAST WILL
DOMINATE INDIANA WEATHER INTO TUESDAY. AT THAT POINT...ANOTHER LOW
PRESSURE SYSTEM TRAVELING FROM THE NORTH PLAINS TO THE OHIO VALLEY
WILL TAKE CHARGE OF HOOSIER WEATHER. FINALLY...A LARGE AREA OF
HIGH PRESSURE WILL MOVE IN THURSDAY AND STICK AROUND INTO THE WEEKEND.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1046 AM EDT SUN APR 22 2012
DRY FORECAST FOR TODAY STILL LOOKS GOOD WITH ONLY PRECIPITATION
OVER SOUTHERN ILLINOIS CURRENTLY MOVING TO THE SOUTHEAST. INCREASED
PERCENTAGE OF SKY COVER TO BETTER MATCH SATELLITE LOOP BUT THIS
DID NOT RESULT IN ANY CHANGE TO THE ZFP WORDING. HIGH TEMPERATURES
IN THE LOW 50S EAST TO AROUND 60 SOUTHWEST STILL LOOK REASONABLE
AND WITH HRRR GOING WARMER BUT RUC AND SREFS GOING COLDER THINK
LEAVING HIGHS ALONE AT THIS POINT IS THE BEST BET. COULD SEE SOME
WIND GUSTS AROUND 20-25KTS THIS AFTERNOON/EVENING BASED ON
FORECAST SOUNDINGS.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
ISSUED AT 248 AM EDT SUN APR 22 2012
BIGGEST PROBLEM IS IF ANY POPS NEEDED TUESDAY NIGHT.
DONT SEE NEED FOR ANY BEFORE THEN. MAIN MODEL FIELDS CLOSE ON BIG
LOW ALOFT SLOWLY PULLING AWAY. CAN NOT SEE ANYTHING THAT WOULD
JUSTIFY ON AND OFF SLGT CHANCE MET HAS MONDAY NIGHT OR
TUESDAY...SO GOING WITH MAV. PROBABLY MOSTLY CLEAR TOMORROW AND
TOMORROW NIGHT. MAY SEE SOME CLOUDS IN WARM ADVECTION ON TUESDAY.
RETURNING TO TUESDAY NIGHT...LATEST MEX HAS BACKED AWAY FROM
CHANCE POPS IT HAD EARLIER. THIS SEEMS LOGICAL SINCE LARGE RIDGE
SHOULD STILL BE TO OUR WEST. FOR JUST ONE RUN THAT FAR OUT I AM
NOT WILLING TO GO ALL THE WAY FROM CHANCE TO TOTALLY DRY...BUT
WILL CUT BACK TO SLIGHT CHANCE.
GUIDANCE TEMPS VERY CLOSE...WHICH MAKES SENSE CONSIDERING
SIMILARITY OF PARENT MODELS. TO EXTENT THEY DIFFER USING
CONSENSUS TO CAPTURE BEST OF BOTH.
AS PER DISCUSSION WITH NEIGHBORS...TEMPS MAY NOT QUITE MAKE IT TO
FREEZING TONIGHT...BUT WILL BE CLOSE ENOUGH SO A WATCH IS
INDICATED TO HIGHLIGHT THE POSSIBILITY.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ISSUED AT 248 AM EDT SUN APR 22 2012
LATEST INITIALIZATION IS SHOWING LIKELY POPS ACROSS MOST OF FORECAST
AREA ON WEDNESDAY AS SURFACE LOW AND ASSOCIATED FRONT MOVE ACROSS
CENTRAL INDIANA. HOWEVER...PRECIP WILL QUICKLY EXIT THE AREA BY
THURSDAY MORNING AS FRONT MOVES SOUTH AND ISENTROPIC LIFT
DECREASES. MODELS ARE IN LINE WITH THAT FORECAST...SO WILL NOT
DEVIATE FROM INITIALIZATION.
HIGH PRESSURE WILL QUICKLY BUILD INTO CENTRAL INDIANA ON
THURSDAY...BRINGING DRY CONDITIONS UNTIL SATURDAY. AFTER
THAT...MODELS EJECT ANOTHER LOW OUT OF THE CENTRAL PLAINS ON SUNDAY
MORNING...BUT THERE IS TOO MUCH UNCERTAINTY AT THIS TIME TO MAKE ANY
ADJUSTMENTS TO DAY 7.
TEMPS WILL BE KIND OF COOL...BUT WHAT IS ACTUALLY NORMAL FOR THIS
TIME OF YEAR. INITIALIZATION IS HANDLING THE PATTERN WELL...SO NO
DEVIATIONS.
&&
.AVIATION /DISCUSSION FOR THE 221800Z TAF ISSUANCE/...
ISSUED AT 108 PM EDT SUN APR 22 2012
VFR CONDITIONS FOR THE PERIOD...HOWEVER WINDY AT
TIMES...ESPECIALLY MONDAY.
THIS AFTERNOON CAN BE CHARACTERIZED BY PLENTY OF BKN-OVC
LOW/MID/HIGH LEVEL CLOUD COVER MOVING ACROSS THE STATE. TRIED BEST
TO DEPICT THE MORE PREVALENT CLOUD DECKS...AROUND 5K FT AND 12K
FT...HOWEVER COVERAGE WILL VARY. BY LATE THIS EVENING THE SKIES
CLEAR OUT AND WILL REMAIN CLEAR FOR THE REST OF THE FORECAST
PERIOD. INTEREST THEN TURNS TO WIND FORECAST AS FORMERLY EASTERLY
WINDS HAVE BACKED TO THE NORTH/NORTHEAST AND INCREASED TO
SUSTAINED SPEEDS OF 12 TO 14 KTS WITH GUSTS UP TO 25 KTS FOR THE
REMAINDER OF THE DAY. GUSTS ARE STILL EXPECTED TO TAPER OFF THIS
EVENING...BUT SUSTAINED WINDS WILL REMAIN AROUND 10 KT ALL
LOCATIONS AND THEN PICK BACK UP WITH A TIGHTENING PRESSURE
GRADIENT EARLY TOMORROW MORNING WHERE BETWEEN 15 TO 17Z MANY
SUSTAINED WINDS WILL INCREASE TO 15+ KT WITH GUSTS NEAR 30 KT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM LATE TONIGHT THROUGH MONDAY MORNING FOR INZ021-
028>031-035>049-051>057-060>065-070>072.
&&
$$
SYNOPSIS...JK
NEAR TERM...CP
SHORT TERM...JK
LONG TERM....TDUD
AVIATION...SMF
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
115 PM EDT SUN APR 22 2012
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 248 AM EDT SUN APR 22 2012
A STRONG LOW PRESSURE SYSTEM MOVING ALONG THE EAST COAST WILL
DOMINATE INDIANA WEATHER INTO TUESDAY. AT THAT POINT...ANOTHER LOW
PRESSURE SYSTEM TRAVELING FROM THE NORTH PLAINS TO THE OHIO VALLEY
WILL TAKE CHARGE OF HOOSIER WEATHER. FINALLY...A LARGE AREA OF
HIGH PRESSURE WILL MOVE IN THURSDAY AND STICK AROUND INTO THE WEEKEND.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1046 AM EDT SUN APR 22 2012
DRY FORECAST FOR TODAY STILL LOOKS GOOD WITH ONLY PRECIPITATION
OVER SOUTHERN ILLINOIS CURRENTLY MOVING TO THE SOUTHEAST. INCREASED
PERCENTAGE OF SKY COVER TO BETTER MATCH SATELLITE LOOP BUT THIS
DID NOT RESULT IN ANY CHANGE TO THE ZFP WORDING. HIGH TEMPERATURES
IN THE LOW 50S EAST TO AROUND 60 SOUTHWEST STILL LOOK REASONABLE
AND WITH HRRR GOING WARMER BUT RUC AND SREFS GOING COLDER THINK
LEAVING HIGHS ALONE AT THIS POINT IS THE BEST BET. COULD SEE SOME
WIND GUSTS AROUND 20-25KTS THIS AFTERNOON/EVENING BASED ON
FORECAST SOUNDINGS.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
ISSUED AT 248 AM EDT SUN APR 22 2012
BIGGEST PROBLEM IS IF ANY POPS NEEDED TUESDAY NIGHT.
DONT SEE NEED FOR ANY BEFORE THEN. MAIN MODEL FIELDS CLOSE ON BIG
LOW ALOFT SLOWLY PULLING AWAY. CAN NOT SEE ANYTHING THAT WOULD
JUSTIFY ON AND OFF SLGT CHANCE MET HAS MONDAY NIGHT OR
TUESDAY...SO GOING WITH MAV. PROBABLY MOSTLY CLEAR TOMORROW AND
TOMORROW NIGHT. MAY SEE SOME CLOUDS IN WARM ADVECTION ON TUESDAY.
RETURNING TO TUESDAY NIGHT...LATEST MEX HAS BACKED AWAY FROM
CHANCE POPS IT HAD EARLIER. THIS SEEMS LOGICAL SINCE LARGE RIDGE
SHOULD STILL BE TO OUR WEST. FOR JUST ONE RUN THAT FAR OUT I AM
NOT WILLING TO GO ALL THE WAY FROM CHANCE TO TOTALLY DRY...BUT
WILL CUT BACK TO SLIGHT CHANCE.
GUIDANCE TEMPS VERY CLOSE...WHICH MAKES SENSE CONSIDERING
SIMILARITY OF PARENT MODELS. TO EXTENT THEY DIFFER USING
CONSENSUS TO CAPTURE BEST OF BOTH.
AS PER DISCUSSION WITH NEIGHBORS...TEMPS MAY NOT QUITE MAKE IT TO
FREEZING TONIGHT...BUT WILL BE CLOSE ENOUGH SO A WATCH IS
INDICATED TO HIGHLIGHT THE POSSIBILITY.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ISSUED AT 248 AM EDT SUN APR 22 2012
LATEST INITIALIZATION IS SHOWING LIKELY POPS ACROSS MOST OF FORECAST
AREA ON WEDNESDAY AS SURFACE LOW AND ASSOCIATED FRONT MOVE ACROSS
CENTRAL INDIANA. HOWEVER...PRECIP WILL QUICKLY EXIT THE AREA BY
THURSDAY MORNING AS FRONT MOVES SOUTH AND ISENTROPIC LIFT
DECREASES. MODELS ARE IN LINE WITH THAT FORECAST...SO WILL NOT
DEVIATE FROM INITIALIZATION.
HIGH PRESSURE WILL QUICKLY BUILD INTO CENTRAL INDIANA ON
THURSDAY...BRINGING DRY CONDITIONS UNTIL SATURDAY. AFTER
THAT...MODELS EJECT ANOTHER LOW OUT OF THE CENTRAL PLAINS ON SUNDAY
MORNING...BUT THERE IS TOO MUCH UNCERTAINTY AT THIS TIME TO MAKE ANY
ADJUSTMENTS TO DAY 7.
TEMPS WILL BE KIND OF COOL...BUT WHAT IS ACTUALLY NORMAL FOR THIS
TIME OF YEAR. INITIALIZATION IS HANDLING THE PATTERN WELL...SO NO
DEVIATIONS.
&&
.AVIATION /DISCUSSION FOR THE 221800Z TAF ISSUANCE/...
ISSUED AT 108 PM EDT SUN APR 22 2012
VFR CONDITIONS FOR THE PERIOD...HOWEVER WINDY AT
TIMES...ESPECIALLY MONDAY.
THIS AFTERNOON CAN BE CHARACTERIZED BY PLENTY OF BKN-OVC
LOW/MID/HIGH LEVEL CLUD COVER MOVING ACROSS THE STATE. TRIED BEST
TO DEPICT THE MORE PREVALENT CLOUD DECKS...AROUND 5K FT AND 12K
FT...HOWEVER COVERAGE WILL VARY. BY LATE THIS EVENING THE SKIES
CLEAR OUT AND WILL REMAIN CLEAR FOR THE REST OF THE FORECAST
PERIOD. INTEREST THEN TURNS TO WIND FORECAST AS FORMERLY EASTERLY
WINDS HAVE BACKED TO THE NORTH/NORTHEAST AND INCREASED TO
SUSTAINED SPEEDS OF 12 TO 14 KTS WITH GUSTS UP TO 25 KTS FOR THE
REMAINDER OF THE DAY. GUSTS ARE STILL EXPECTED TO TAPER OFF THIS
EVENING...BUT SUSTAINED WINDS WILL REMAIN AROUND 10 KT ALL
LOCATIONS AND THEN PICK BACK UP WITH A TIGHTENING PRESSURE
GRADIENT EARLY TOMORROW MORNING WHERE BETWEEN 15-17Z MANY
SUSTAINED WINDS WILL INCREASE TO 15+ KT WITH GUSTS NEAR 30 KT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM LATE TONIGHT THROUGH MONDAY MORNING FOR INZ021-
028>031-035>049-051>057-060>065-070>072.
&&
$$
SYNOPSIS...JK
NEAR TERM...CP
SHORT TERM...JK
LONG TERM....TDUD
AVIATION...SMF
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1047 AM EDT SUN APR 22 2012
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW
&&
.SYNOPSIS...
ISSUED AT 248 AM EDT SUN APR 22 2012
A STRONG LOW PRESSURE SYSTEM MOVING ALONG THE EAST COAST WILL
DOMINATE INDIANA WEATHER INTO TUESDAY. AT THAT POINT...ANOTHER LOW
PRESSURE SYSTEM TRAVELING FROM THE NORTH PLAINS TO THE OHIO VALLEY
WILL TAKE CHARGE OF HOOSIER WEATHER. FINALLY...A LARGE AREA OF
HIGH PRESSURE WILL MOVE IN THURSDAY AND STICK AROUND INTO THE WEEKEND.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1046 AM EDT SUN APR 22 2012
DRY FORECAST FOR TODAY STILL LOOKS GOOD WITH ONLY PRECIPITATION
OVER SOUTHERN ILLINOIS CURRENTLY MOVING TO THE SOUTHEAST. INCREASED
PERCENTAGE OF SKY COVER TO BETTER MATCH SATELLITE LOOP BUT THIS
DID NOT RESULT IN ANY CHANGE TO THE ZFP WORDING. HIGH TEMPERATURES
IN THE LOW 50S EAST TO AROUND 60 SOUTHWEST STILL LOOK REASONABLE
AND WITH HRRR GOING WARMER BUT RUC AND SREFS GOING COLDER THINK
LEAVING HIGHS ALONE AT THIS POINT IS THE BEST BET. COULD SEE SOME
WIND GUSTS AROUND 20-25KTS THIS AFTERNOON/EVENING BASED ON
FORECAST SOUNDINGS.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
ISSUED AT 248 AM EDT SUN APR 22 2012
BIGGEST PROBLEM IS IF ANY POPS NEEDED TUESDAY NIGHT.
DONT SEE NEED FOR ANY BEFORE THEN. MAIN MODEL FIELDS CLOSE ON BIG
LOW ALOFT SLOWLY PULLING AWAY. CAN NOT SEE ANYTHING THAT WOULD
JUSTIFY ON AND OFF SLGT CHANCE MET HAS MONDAY NIGHT OR
TUESDAY...SO GOING WITH MAV. PROBABLY MOSTLY CLEAR TOMORROW AND
TOMORROW NIGHT. MAY SEE SOME CLOUDS IN WARM ADVECTION ON TUESDAY.
RETURNING TO TUESDAY NIGHT...LATEST MEX HAS BACKED AWAY FROM
CHANCE POPS IT HAD EARLIER. THIS SEEMS LOGICAL SINCE LARGE RIDGE
SHOULD STILL BE TO OUR WEST. FOR JUST ONE RUN THAT FAR OUT I AM
NOT WILLING TO GO ALL THE WAY FROM CHANCE TO TOTALLY DRY...BUT
WILL CUT BACK TO SLIGHT CHANCE.
GUIDANCE TEMPS VERY CLOSE...WHICH MAKES SENSE CONSIDERING
SIMILARITY OF PARENT MODELS. TO EXTENT THEY DIFFER USING
CONSENSUS TO CAPTURE BEST OF BOTH.
AS PER DISCUSSION WITH NEIGHBORS...TEMPS MAY NOT QUITE MAKE IT TO
FREEZING TONIGHT...BUT WILL BE CLOSE ENOUGH SO A WATCH IS
INDICATED TO HIGHLIGHT THE POSSIBILITY.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ISSUED AT 248 AM EDT SUN APR 22 2012
LATEST INITIALIZATION IS SHOWING LIKELY POPS ACROSS MOST OF FORECAST
AREA ON WEDNESDAY AS SURFACE LOW AND ASSOCIATED FRONT MOVE ACROSS
CENTRAL INDIANA. HOWEVER...PRECIP WILL QUICKLY EXIT THE AREA BY
THURSDAY MORNING AS FRONT MOVES SOUTH AND ISENTROPIC LIFT
DECREASES. MODELS ARE IN LINE WITH THAT FORECAST...SO WILL NOT
DEVIATE FROM INITIALIZATION.
HIGH PRESSURE WILL QUICKLY BUILD INTO CENTRAL INDIANA ON
THURSDAY...BRINGING DRY CONDITIONS UNTIL SATURDAY. AFTER
THAT...MODELS EJECT ANOTHER LOW OUT OF THE CENTRAL PLAINS ON SUNDAY
MORNING...BUT THERE IS TOO MUCH UNCERTAINTY AT THIS TIME TO MAKE ANY
ADJUSTMENTS TO DAY 7.
TEMPS WILL BE KIND OF COOL...BUT WHAT IS ACTUALLY NORMAL FOR THIS
TIME OF YEAR. INITIALIZATION IS HANDLING THE PATTERN WELL...SO NO
DEVIATIONS.
&&
.AVIATION /DISCUSSION FOR THE 22/1200Z TAF ISSUANCE/...
ISSUED AT 1022 AM EDT SUN APR 22 2012
1030Z UPDATE...FEW UPDATES TO TAFS TO ACCOUNT FOR LATEST TRENDS.
BELIEVE THE GUSTIER WINDS WILL NOT ARRIVE UNTIL CLOSER TO 18Z THIS
AFTERNOON...THOUGH THEY WILL PICK UP TO 10-12 KT IN THE NEXT HOUR
OR TWO AND MAY GUST AROUND 20 KT BEFORE THEN. THIS WAS ACCOUNTED
FOR IN THE TAFS. MADE SOME MINOR ADJUSTMENTS TO SKY COVER. KIND
AND A FEW OTHER NON-FORECAST SITES ARE REPORTING SOME MVFR CEILINGS
AROUND 3K FT. THIS SHOULD BE BRIEF AND WILL LIFT/MIX OUT IN THE
NEXT HR OR SO.
PREVIOUS DISCUSSION FOLLOWS...
ISSUED AT 733 AM EDT SUN APR 22 2012
THE TAF PERIOD WILL START OUT WITH SCATTERED TO BROKEN MID LEVEL
CLOUD DECKS...AND GRADUALLY CLEAR OUT BY TONIGHT. SO...VFR
CONDITIONS WILL BE THE PREVAILING FLIGHT CATEGORY FOR DURATION OF
TAF PERIOD. THE MAIN THREAT THOUGH WILL BE THE STRONG WINDS. THE
CURRENT EASTERLY WINDS WILL BACK TO THE NORTHEAST BY MID MORNING
AND INCREASE TO SUSTAINED SPEEDS OF 12 TO 14 KTS WITH GUSTS UP TO
25 KTS FOR THE REMAINDER OF THE DAY. GUSTS WILL TAPER OFF THIS
EVENING...BUT WINDS WILL RETAIN THEIR NORTHERLY COMPONENT AND
REMAIN BREEZY THROUGH THE NIGHT. TOMORROW MORNING...NORTH WINDS
WILL INCREASE ONCE AGAIN WITH GUSTS UP TO 30 KTS AS PRESSURE
GRADIENT TIGHTENS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM LATE TONIGHT THROUGH MONDAY MORNING FOR INZ021-
028>031-035>049-051>057-060>065-070>072.
&&
$$
SYNOPSIS...JK
NEAR TERM...CP
SHORT TERM...JK
LONG TERM....TDUD
AVIATION...SMF
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1234 PM CDT SUN APR 22 2012
.AVIATION...
CLEAR TO MOSTLY CLEAR CONDITIONS WILL PERSIST ALONG WITH VFR
VISIBILITIES THROUGH AT LEAST 24/00Z. HIGH PRESSURE FROM ONTARIO
WILL BRING COOL AIR INTO THE AREA ON NE WINDS OF 5 TO 15 MPH
THROUGH MONDAY AFTERNOON. NICHOLS
&&
.PREV DISCUSSION... /ISSUED 636 AM CDT SUN APR 22 2012/
UPDATE...
RADAR TRENDS SHOW A GENERAL DECREASE IN AREAL COVERAGE AND
INTENSITY OF THE PRECIP OVER THE PAST 3 HRS. RUC TRENDS INDICATE
THE SUPPORT HELPING TO GENERATE THE PRECIPITATION WILL DISSIPATE
OVER THE NEXT 3-4 HRS. RECEIVED A SPOTTER REPORT OF SLEET IN JO
DAVIESS COUNTY SHORTLY AFT 09Z. INITIALLY THERE WAS NOTHING
SUPPORTING THIS IN OBS OR RADAR BUT AROUND 0930Z THERE WAS A NOTED
INCREASE IN REFLECTIVITY MOVING INTO CARROLL COUNTY. THUS IT IS
POSSIBLE THE RADAR WAS PARTIALLY OVERSHOOTING THE PRECIPITATION IN
THAT AREA.
PRECIPITATION IN THE NORTHEAST PART OF THE CWFA IS RAPIDLY FALLING
APART AS THE BETTER FORCING/CONVERGENCE SHIFTS TO THE SOUTH AND
WEST. SOME SPRINKLES MAY BE POSSIBLE OVER THE NORTHEAST THIRD TO
40 PERCENT OF THE CWFA SHORTLY AFT 12Z BUT THEY SHOULD DISSIPATE
BY 8 AM.
OVERALL...THE CURRENT FCST STILL LOOKS TO BE ON TRACK WITH NO
UPDATED PLANNED ATTM. 08
PREV DISCUSSION... /ISSUED 316 AM CST SUN APR 22 2012/
SYNOPSIS...
06Z SFC ANALYSIS HAS WEAK LOWS FROM SOUTHERN MINNESOTA INTO SOUTH
CENTRAL IOWA. AN INVERTED TROF RAN FROM A LOW NEAR KMCW SOUTHEAST TO
KSPI. DEW POINTS WERE IN THE 40S AROUND THE INVERTED TROF WITH 30S
OVER MOST OF THE GREAT LAKES AND NORTHERN PLAINS.
RADAR TRENDS THE PAST SEVERAL HOURS SHOW A GENERAL WEAKENING OF THE
PRECIPITATION WITH MAINLY LIGHT RAIN AND SPRINKLES AROUND THE
INVERTED TROF.
SHORT TERM...TODAY AND TONIGHT
SFC DATA AND RUC TRENDS INDICATE MOST OF THE PRECIPITATION ACROSS
THE CWFA IS ASSOCIATED WITH THE INVERTED TROF. THE RUC DOES HAVE
STRONG FORCING ON THE 295K THETA SFC WHICH APPEARS IS RESPONSIBLE
FOR THE WEAK BAND OF SPRINKLES/-RA TO THE EAST OF THE INVERTED TROF.
RUC TRENDS SHOW THIS FORCING WEAKENING THROUGH SUNRISE AS THE
INVERTED TROF SLOWLY MOVES TO THE SOUTH AND WEST. THUS ANY
PRECIPITATION SHOULD BE CONFINED TO ROUGHLY THE SOUTHWEST HALF OF
THE CWFA AFTER SUNRISE.
THE INVERTED TROF GENERALLY EXITS THE CWFA BY MID MORNING AND THE
OVERALL FORCING/CONVERGENCE WEAKENS FURTHER. THUS MOST IF NOT ALL
THE PRECIPITATION SHOULD BE OVER BEFORE MID DAY. QUIET AND THEN
MAINLY DRY CONDITIONS SHOULD BE SEEN ACROSS THE AREA DURING THE
AFTERNOON.
TONIGHT...QUIET CONDITIONS WILL BE SEEN ACROSS THE CWFA.
INTERESTINGLY...THE HEAVY RAIN AND MCS TOOLS BRING CONVERGENCE AND
HIGHER RH DOWN ACROSS THE AREA. THE RH IS TRACEABLE TO THE LOW AND
MID CLOUDS CURRENTLY ACROSS NORTHERN MINNESOTA. SO...IT IS
CONCEIVABLE THAT A SUBTLE SHORTWAVE TOPPING THE RIDGE MAY BRING DOWN
THESE CLOUDS INTO THE AREA. IF CORRECT...THE CLOUDS SHOULD BREAK UP
SOMEWHAT DUE TO THE SUBSIDENCE OVER THE WESTERN GREAT LAKES IN THE
WAKE OF THE DEVELOPING EAST COAST STORM. 08
LONG TERM...MONDAY THROUGH NEXT SATURDAY
MONDAY WE REMAIN IN THE STRONG NORTHWEST FLOW AS THE STORM SYSTEM
OVER THE EAST COAST DEEPENS AND CAUSES THE FLOW TO AMPLIFY STRONGLY
OVER THE CONUS. THIS WILL ACT TO FUNNEL COOLER THAN NORMAL AIR DOWN
INTO THE REGION INTO TUESDAY. THERE IS SOME POTENTIAL FOR SOME
DIURNALLY DRIVEN SHOWERS ON MONDAY AFTERNOON WITH THE SURFACE RIDGE
STILL TO THE WEST AND SOME WEAK CONVERGENCE TO HELP START THEM OFF.
BY TUESDAY THE SURFACE RIDGE WILL HAVE SHIFTED EAST OF THE AREA SO
THIS IS LESS OF A CONCERN AND HAVE PUT IN A DRY FORECAST AND WARMER
TEMPERATURES.
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. A SHORTWAVE MOVES OVER THE
TOP OF THE UPPER LEVEL RIDGE TO OUR WEST DROPS DOWN IN THE NORTHWEST
FLOW. THIS...COMBINED WITH THE BAROCLINIC ZONE OVER THE AREA AS A
RESULT OF THE COLD AIR POOL TO OUR EAST SHOULD ACT TO GENERATE SOME
FRONTOGENESIS AS THIS FEATURES MOVES ON BY. TUESDAY NIGHT THE WARM
AIR ADVECTION/ISENTROPIC LIFT SHOWERS SHOULD BE MOVING INTO THE
AREA. THE SURFACE LOW MOVES ACROSS IOWA DURING THE DAY ON
WEDNESDAY...AND WE WILL HAVE THE COLD SIDE OF THE SYSTEM MOVE ACROSS
WEDNESDAY NIGHT. THERE ARE SOME CONCERNS THAT THE BULK OF THIS
SYSTEM WILL AFFECT AREAS NORTHEAST OF THE CWA DEPENDING ON THE
MODEL YOU LOOK AT...SO THE FORECAST IS STILL FOR JUST CHANCE POPS.
TEMPERATURES WITH THIS SYSTEM WILL BE WARMER THAN NORMAL TUESDAY
NIGHT AND WEDNESDAY...WITH COLDER TEMPS FOR WEDNESDAY NIGHT AS THE
TRAILING COLD FRONT MOVES THROUGH. THURSDAY TO BE COLDER AGAIN
BEHIND THE EXITING SYSTEM.
THURSDAY NIGHT THROUGH NEXT SATURDAY...HERE MORE QUESTION MARKS
ENTER THE FORECAST WITH MORE DIFFERENCES IN THE MODELS. THE UPPER
LEVEL RIDGE TO OUR WEST DURING THE MIDDLE OF THE WEAK BECOMES RATHER
PINCHED...AND IT GETS BODILY SHOVED EAST AS A FAIRLY POTENT UPPER
LOW SWINGS ACROSS THE FOUR CORNERS STATES. BY SATURDAY MORNING THE
MODELS ARE PUSHING A WARM AIR ADVECTION WING OF PRECIPITATION INTO
THE FORECAST AREA. WOULD NOT BE TOO SURPRISED TO SEE THIS SLOW DOWN
SOME...THOUGH THE MODELS HAVE BEEN FAIRLY CONSISTENT SO FAR.
LE
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
NICHOLS
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
636 AM CDT SUN APR 22 2012
.UPDATE...
RADAR TRENDS SHOW A GENERAL DECREASE IN AREAL COVERAGE AND
INTENSITY OF THE PRECIP OVER THE PAST 3 HRS. RUC TRENDS INDICATE
THE SUPPORT HELPING TO GENERATE THE PRECIPITATION WILL DISSIPATE
OVER THE NEXT 3-4 HRS. RECEIVED A SPOTTER REPORT OF SLEET IN JO
DAVIESS COUNTY SHORTLY AFT 09Z. INITIALLY THERE WAS NOTHING
SUPPORTING THIS IN OBS OR RADAR BUT AROUND 0930Z THERE WAS A NOTED
INCREASE IN REFLECTIVITY MOVING INTO CARROLL COUNTY. THUS IT IS
POSSIBLE THE RADAR WAS PARTIALLY OVERSHOOTING THE PRECIPITATION IN
THAT AREA.
PRECIPITATION IN THE NORTHEAST PART OF THE CWFA IS RAPIDLY FALLING
APART AS THE BETTER FORCING/CONVERGENCE SHIFTS TO THE SOUTH AND
WEST. SOME SPRINKLES MAY BE POSSIBLE OVER THE NORTHEAST THIRD TO
40 PERCENT OF THE CWFA SHORTLY AFT 12Z BUT THEY SHOULD DISSIPATE
BY 8 AM.
OVERALL...THE CURRENT FCST STILL LOOKS TO BE ON TRACK WITH NO
UPDATED PLANNED ATTM. ..08..
&&
.AVIATION...
RADAR TRENDS THE PAST SEVERAL HOURS SHOW A GENERAL DECREASE IN
REGARDS TO INTENSITY AND AREAL COVERAGE OF PRECIPITATION. VCSH
WILL BE POSSIBLE AT ALL TAF SITES THROUGH 14Z/22 AS RUC TRENDS
INDICATES THE OVERALL LIFT SUPPORTING SHRA ACTIVITY WILL THEN
DISSIPATE. OTHERWISE EXPECT VFR CONDITIONS THROUGH 06Z/23. IT IS
STILL UNCERTAIN WHETHER MVFR VSBYS CONDITIONS WILL DVLP AFT
06Z/23. AS A RESULT THEY WERE NOT INCLUDED IN THE 12Z TAFS. ..08..
&&
.PREV DISCUSSION... /ISSUED 316 AM CST SUN APR 22 2012/
SYNOPSIS...
06Z SFC ANALYSIS HAS WEAK LOWS FROM SOUTHERN MINNESOTA INTO SOUTH
CENTRAL IOWA. AN INVERTED TROF RAN FROM A LOW NEAR KMCW SOUTHEAST TO
KSPI. DEW POINTS WERE IN THE 40S AROUND THE INVERTED TROF WITH 30S
OVER MOST OF THE GREAT LAKES AND NORTHERN PLAINS.
RADAR TRENDS THE PAST SEVERAL HOURS SHOW A GENERAL WEAKENING OF THE
PRECIPITATION WITH MAINLY LIGHT RAIN AND SPRINKLES AROUND THE
INVERTED TROF.
SHORT TERM...TODAY AND TONIGHT
SFC DATA AND RUC TRENDS INDICATE MOST OF THE PRECIPITATION ACROSS
THE CWFA IS ASSOCIATED WITH THE INVERTED TROF. THE RUC DOES HAVE
STRONG FORCING ON THE 295K THETA SFC WHICH APPEARS IS RESPONSIBLE
FOR THE WEAK BAND OF SPRINKLES/-RA TO THE EAST OF THE INVERTED TROF.
RUC TRENDS SHOW THIS FORCING WEAKENING THROUGH SUNRISE AS THE
INVERTED TROF SLOWLY MOVES TO THE SOUTH AND WEST. THUS ANY
PRECIPITATION SHOULD BE CONFINED TO ROUGHLY THE SOUTHWEST HALF OF
THE CWFA AFTER SUNRISE.
THE INVERTED TROF GENERALLY EXITS THE CWFA BY MID MORNING AND THE
OVERALL FORCING/CONVERGENCE WEAKENS FURTHER. THUS MOST IF NOT ALL
THE PRECIPITATION SHOULD BE OVER BEFORE MID DAY. QUIET AND THEN
MAINLY DRY CONDITIONS SHOULD BE SEEN ACROSS THE AREA DURING THE
AFTERNOON.
TONIGHT...QUIET CONDITIONS WILL BE SEEN ACROSS THE CWFA.
INTERESTINGLY...THE HEAVY RAIN AND MCS TOOLS BRING CONVERGENCE AND
HIGHER RH DOWN ACROSS THE AREA. THE RH IS TRACEABLE TO THE LOW AND
MID CLOUDS CURRENTLY ACROSS NORTHERN MINNESOTA. SO...IT IS
CONCEIVABLE THAT A SUBTLE SHORTWAVE TOPPING THE RIDGE MAY BRING DOWN
THESE CLOUDS INTO THE AREA. IF CORRECT...THE CLOUDS SHOULD BREAK UP
SOMEWHAT DUE TO THE SUBSIDENCE OVER THE WESTERN GREAT LAKES IN THE
WAKE OF THE DEVELOPING EAST COAST STORM. ..08..
LONG TERM...MONDAY THROUGH NEXT SATURDAY
MONDAY WE REMAIN IN THE STRONG NORTHWEST FLOW AS THE STORM SYSTEM
OVER THE EAST COAST DEEPENS AND CAUSES THE FLOW TO AMPLIFY STRONGLY
OVER THE CONUS. THIS WILL ACT TO FUNNEL COOLER THAN NORMAL AIR DOWN
INTO THE REGION INTO TUESDAY. THERE IS SOME POTENTIAL FOR SOME
DIURNALLY DRIVEN SHOWERS ON MONDAY AFTERNOON WITH THE SURFACE RIDGE
STILL TO THE WEST AND SOME WEAK CONVERGENCE TO HELP START THEM OFF.
BY TUESDAY THE SURFACE RIDGE WILL HAVE SHIFTED EAST OF THE AREA SO
THIS IS LESS OF A CONCERN AND HAVE PUT IN A DRY FORECAST AND WARMER
TEMPERATURES.
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. A SHORTWAVE MOVES OVER THE
TOP OF THE UPPER LEVEL RIDGE TO OUR WEST DROPS DOWN IN THE NORTHWEST
FLOW. THIS...COMBINED WITH THE BAROCLINIC ZONE OVER THE AREA AS A
RESULT OF THE COLD AIR POOL TO OUR EAST SHOULD ACT TO GENERATE SOME
FRONTOGENESIS AS THIS FEATURES MOVES ON BY. TUESDAY NIGHT THE WARM
AIR ADVECTION/ISENTROPIC LIFT SHOWERS SHOULD BE MOVING INTO THE
AREA. THE SURFACE LOW MOVES ACROSS IOWA DURING THE DAY ON
WEDNESDAY...AND WE WILL HAVE THE COLD SIDE OF THE SYSTEM MOVE ACROSS
WEDNESDAY NIGHT. THERE ARE SOME CONCERNS THAT THE BULK OF THIS
SYSTEM WILL AFFECT AREAS NORTHEAST OF THE CWA DEPENDING ON THE
MODEL YOU LOOK AT...SO THE FORECAST IS STILL FOR JUST CHANCE POPS.
TEMPERATURES WITH THIS SYSTEM WILL BE WARMER THAN NORMAL TUESDAY
NIGHT AND WEDNESDAY...WITH COLDER TEMPS FOR WEDNESDAY NIGHT AS THE
TRAILING COLD FRONT MOVES THROUGH. THURSDAY TO BE COLDER AGAIN
BEHIND THE EXITING SYSTEM.
THURSDAY NIGHT THROUGH NEXT SATURDAY...HERE MORE QUESTION MARKS
ENTER THE FORECAST WITH MORE DIFFERENCES IN THE MODELS. THE UPPER
LEVEL RIDGE TO OUR WEST DURING THE MIDDLE OF THE WEAK BECOMES RATHER
PINCHED...AND IT GETS BODILY SHOVED EAST AS A FAIRLY POTENT UPPER
LOW SWINGS ACROSS THE FOUR CORNERS STATES. BY SATURDAY MORNING THE
MODELS ARE PUSHING A WARM AIR ADVECTION WING OF PRECIPITATION INTO
THE FORECAST AREA. WOULD NOT BE TOO SURPRISED TO SEE THIS SLOW DOWN
SOME...THOUGH THE MODELS HAVE BEEN FAIRLY CONSISTENT SO FAR.
LE
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
316 AM CST SUN APR 22 2012
.SYNOPSIS...
06Z SFC ANALYSIS HAS WEAK LOWS FROM SOUTHERN MINNESOTA INTO SOUTH
CENTRAL IOWA. AN INVERTED TROF RAN FROM A LOW NEAR KMCW SOUTHEAST TO
KSPI. DEW POINTS WERE IN THE 40S AROUND THE INVERTED TROF WITH 30S
OVER MOST OF THE GREAT LAKES AND NORTHERN PLAINS.
RADAR TRENDS THE PAST SEVERAL HOURS SHOW A GENERAL WEAKENING OF THE
PRECIPITATION WITH MAINLY LIGHT RAIN AND SPRINKLES AROUND THE
INVERTED TROF.
&&
.SHORT TERM...TODAY AND TONIGHT
SFC DATA AND RUC TRENDS INDICATE MOST OF THE PRECIPITATION ACROSS
THE CWFA IS ASSOCIATED WITH THE INVERTED TROF. THE RUC DOES HAVE
STRONG FORCING ON THE 295K THETA SFC WHICH APPEARS IS RESPONSIBLE
FOR THE WEAK BAND OF SPRINKLES/-RA TO THE EAST OF THE INVERTED TROF.
RUC TRENDS SHOW THIS FORCING WEAKENING THROUGH SUNRISE AS THE
INVERTED TROF SLOWLY MOVES TO THE SOUTH AND WEST. THUS ANY
PRECIPITATION SHOULD BE CONFINED TO ROUGHLY THE SOUTHWEST HALF OF
THE CWFA AFTER SUNRISE.
THE INVERTED TROF GENERALLY EXITS THE CWFA BY MID MORNING AND THE
OVERALL FORCING/CONVERGENCE WEAKENS FURTHER. THUS MOST IF NOT ALL
THE PRECIPITATION SHOULD BE OVER BEFORE MID DAY. QUIET AND THEN
MAINLY DRY CONDITIONS SHOULD BE SEEN ACROSS THE AREA DURING THE
AFTERNOON.
TONIGHT...QUIET CONDITIONS WILL BE SEEN ACROSS THE CWFA.
INTERESTINGLY...THE HEAVY RAIN AND MCS TOOLS BRING CONVERGENCE AND
HIGHER RH DOWN ACROSS THE AREA. THE RH IS TRACEABLE TO THE LOW AND
MID CLOUDS CURRENTLY ACROSS NORTHERN MINNESOTA. SO...IT IS
CONCEIVABLE THAT A SUBTLE SHORTWAVE TOPPING THE RIDGE MAY BRING DOWN
THESE CLOUDS INTO THE AREA. IF CORRECT...THE CLOUDS SHOULD BREAK UP
SOMEWHAT DUE TO THE SUBSIDENCE OVER THE WESTERN GREAT LAKES IN THE
WAKE OF THE DEVELOPING EAST COAST STORM. ..08..
.LONG TERM...MONDAY THROUGH NEXT SATURDAY
MONDAY WE REMAIN IN THE STRONG NORTHWEST FLOW AS THE STORM SYSTEM
OVER THE EAST COAST DEEPENS AND CAUSES THE FLOW TO AMPLIFY STRONGLY
OVER THE CONUS. THIS WILL ACT TO FUNNEL COOLER THAN NORMAL AIR DOWN
INTO THE REGION INTO TUESDAY. THERE IS SOME POTENTIAL FOR SOME
DIURNALLY DRIVEN SHOWERS ON MONDAY AFTERNOON WITH THE SURFACE RIDGE
STILL TO THE WEST AND SOME WEAK CONVERGENCE TO HELP START THEM OFF.
BY TUESDAY THE SURFACE RIDGE WILL HAVE SHIFTED EAST OF THE AREA SO
THIS IS LESS OF A CONCERN AND HAVE PUT IN A DRY FORECAST AND WARMER
TEMPERATURES.
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. A SHORTWAVE MOVES OVER THE
TOP OF THE UPPER LEVEL RIDGE TO OUR WEST DROPS DOWN IN THE NORTHWEST
FLOW. THIS...COMBINED WITH THE BAROCLINIC ZONE OVER THE AREA AS A
RESULT OF THE COLD AIR POOL TO OUR EAST SHOULD ACT TO GENERATE SOME
FRONTOGENESIS AS THIS FEATURES MOVES ON BY. TUESDAY NIGHT THE WARM
AIR ADVECTION/ISENTROPIC LIFT SHOWERS SHOULD BE MOVING INTO THE
AREA. THE SURFACE LOW MOVES ACROSS IOWA DURING THE DAY ON
WEDNESDAY...AND WE WILL HAVE THE COLD SIDE OF THE SYSTEM MOVE ACROSS
WEDNESDAY NIGHT. THERE ARE SOME CONCERNS THAT THE BULK OF THIS
SYSTEM WILL AFFECT AREAS NORTHEAST OF THE CWA DEPENDING ON THE
MODEL YOU LOOK AT...SO THE FORECAST IS STILL FOR JUST CHANCE POPS.
TEMPERATURES WITH THIS SYSTEM WILL BE WARMER THAN NORMAL TUESDAY
NIGHT AND WEDNESDAY...WITH COLDER TEMPS FOR WEDNESDAY NIGHT AS THE
TRAILING COLD FRONT MOVES THROUGH. THURSDAY TO BE COLDER AGAIN
BEHIND THE EXITING SYSTEM.
THURSDAY NIGHT THROUGH NEXT SATURDAY...HERE MORE QUESTION MARKS
ENTER THE FORECAST WITH MORE DIFFERENCES IN THE MODELS. THE UPPER
LEVEL RIDGE TO OUR WEST DURING THE MIDDLE OF THE WEAK BECOMES RATHER
PINCHED...AND IT GETS BODILY SHOVED EAST AS A FAIRLY POTENT UPPER
LOW SWINGS ACROSS THE FOUR CORNERS STATES. BY SATURDAY MORNING THE
MODELS ARE PUSHING A WARM AIR ADVECTION WING OF PRECIPITATION INTO
THE FORECAST AREA. WOULD NOT BE TOO SURPRISED TO SEE THIS SLOW DOWN
SOME...THOUGH THE MODELS HAVE BEEN FAIRLY CONSISTENT SO FAR.
LE
&&
.AVIATION...
MODELS SHOW THE OVERALL FORCING WILL CONTINUE TO WEAKEN THROUGH
12Z/22. THUS VFR CONDITIONS SHOULD BE SEEN FOR ALL TAF SITES. THERE
MAY BE SOME VERY BRIEF PERIODS OF MARGINAL MVFR CONDITIONS AT
KCID/KBRL THROUGH 15Z/22 AND THIS WILL BE EVALUATED FURTHER FOR THE
12Z TAFS. AFT 00Z/23 THE MODELS SHOW GENERALLY LIGHT WINDS WITH A
WEAK AREA OF CONVERGENCE AT THE SURFACE. THIS CONVERGENCE MAY BE A
SIGNAL FOR POTENTIAL MVFR VSBYS DVLPG AFT 06Z/23. ..08..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1138 PM CDT SAT APR 21 2012
...UPDATED AVIATION DISCUSSION...
.SHORT TERM /TONIGHT/...
PRIMARY CONCERN TONIGHT WILL BE THE EVOLUTION OF UPSTREAM SHORT
WAVE/PV ANOMALY...WHICH MODELS BRING RIGHT THROUGH IA LATER
TONIGHT. CURRENT MORE THERMODYNAMICALLY FORCED BAND OF PRECIP
SHOULD EXIT ERN FORECAST AREA BY 00Z FOLLOWED BY LINE OF SCATTERED
SHOWERS/STORMS FOCUSED ON LOW LEVEL CONVERGENCE WITH PASSAGE OF
TROUGH. 20Z SURFACE ANALYSIS PLACES ACTUAL COLD FRONT FROM LOW NEAR
FARGO BACK ALONG ND/SD BORDER. COULD SEE SOME BELOW SEVERE CRITERIA
HAIL/WIND WITH THESE STORMS NW...BUT DECREASING/INCREASING
MLCAPE/CIN RESPECTIVELY SHOULD GRADUALLY WEAKEN STORMS AS THEY GET
INTO CENTRAL IA. RUC MLCAPE APPEARS TO PEAK AT NO MORE THAN 300
J/KG AS IT ENTER FORECAST AREA. ATTENTION WILL THEN TURNS TO
FORCING AND MOISTURE 3KM AND BELOW ASSOCIATED WITH PASSAGE OF SHORT
WAVE WHICH MAINLY APPEARS TO AFFECT NERN HALF OF IA. HAVE HIGH
CHANCE/LIKELY POPS TONIGHT IN THESE AREAS...BUT FEEL THIS WILL BE
FOR A TRANSIENT LOW QPF EVENT.
.LONG TERM /SUNDAY THROUGH SATURDAY/...
AMPLIFIED UPPER PATTERN OVER THE CONUS EARLY NEXT WEEK WITH UPPER
RIDGE CENTERED OVER THE CENTRAL ROCKIES AND A DEEP UPPER TROUGH OVER
THE EASTERN UNITED STATES. SHORTWAVE OVER THE UPPER MIDWEST TODAY IS
FORECAST TO CURVE OUT A DEEP UPPER LOW CENTERED NEAR THE EAST COAST
BY MONDAY. THIS WILL LEAVE CENTRAL IOWA IN INITIALLY NORTHERLY
UPPER FLOW WHICH SHOULD SLOWLY BECOME NORTHWESTERLY BY
TUESDAY/WEDNESDAY AS A SHORTWAVE FLATTENS THE UPPER RIDGE TO THE
WEST. THE MODELS SEEM TO BE IN FAIR AGREEMENT WITH THE GENERAL UPPER
PATTERN...BUT THERE ARE DIFFERENCES MID WEEK CONCERNING THE PASSAGE
OF A SIGNIFICANT COLD FRONT. THE 12Z OPERATIONAL GFS BRINGS A
STRONG CANADIAN HIGH DOWN INTO THE UPPER MIDWEST DURING THE
WEDNESDAY THROUGH FRIDAY TIME PERIOD. THE 12Z ECMWF IS SIMILAR TO
THE 12Z GFS CONCERNING THE PLACEMENT AND STRENGTH OF THE CANADIAN
HIGH.
12Z NAM/GFS BOTH LINGER PRECIPITATION OVER CENTRAL IOWA ON SUNDAY IN
THE VICINITY OF AN INVERTED TROUGH. THE TROUGH SHOULD WEAKEN DURING
THE DAY AS THE SURFACE RIDGE BUILDS IN. EXPECT CLOUDS ON SUNDAY
WITH SMALL SHOWER CHANCES THROUGH NOON. SKIES SHOULD CLEAR SUNDAY
NIGHT UNDER APPROACHING HIGH ALLOWING TEMPERATURES TO FALL NEAR
FREEZING IN SPOTS. CONDITIONS SHOULD BE FAVORABLE FOR FROST...LIGHT
WINDS AND CLEAR SKIES.
AS THE UPPER FLOW FLATTENS BY TUESDAY AND SURFACE AND LOW-LEVEL FLOW
BECOMES WEST SOUTHWEST WITH STRONG WARM ADVECTION...EXPECT
TEMPERATURES TO WARM INTO THE 80S OVER WESTERN IOWA.
MODEL UNCERTAINTY IN THE LONG RANGE...DAY SIX AND SEVEN...WILL
RESULT IN MODERATE POPS. NEXT WESTERN CONUS UPPER TROUGH AND
ACCOMPANYING SURFACE FEATURES SHOULD IMPACT CENTRAL IOWA DURING THIS
TIME PERIOD. IN ALL CASES...THE PATTERN SHOULD BECOME FAVORABLE FOR
THUNDERSTORMS BY THE END OF THE FORECAST PERIOD.
&&
.AVIATION...22/06Z
SHORTWAVE WILL CONTINUE TO PRESS FURTHER EAST OVERNIGHT. FAIRLY
SHARP PRESSURE PRESSURE GRADIENT SHOULD CAUSE SOME GUSTY WINDS AT
FOD/MCW/DSM AREAS BY AROUND 08Z...WITH MVFR CIGS MOVING IN WITH THE
CAA. HAVE MENTION OF MVFR CIGS AT FOD/MCW/DSM/ALO B/T 07-10Z...BUT
KEPT WINDS DOWN AT ALO AS TROUGH LOOKS TO PUSH THROUGH SUNDAY
MORNING. CONFIDENT STRATUS WILL STICK AROUND UNTIL AT LEAST NEXT
FORECAST UPDATE...AND LIKELY INTO THE LATE MORNING HOURS SUNDAY.
HAVE CONDITIONS IMPROVING AFTER 15Z SUNDAY.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...SMALL
LONG TERM...JOHNSON
AVIATION...PODRAZIK
AREA FORECAST DISCUSSION
NWS PADUCAH KY
326 PM CDT SUN APR 22 2012
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 305 PM CDT SUN APR 22 2012
THE SHORT TERM CONCERN FOR TONIGHT WILL BE THE DEVELOPMENT OF FROST
AFTER MIDNIGHT. IT WAS A TOUGH CALL TO DETERMINE WHETHER THE
DURATION/INTENSITY OF ANY FROST DEVELOPMENT WOULD BE ENOUGH TO
WARRANT THE ISSUANCE OF A FROST ADVISORY FOR PARTS OF THE WFO PAH
FORECAST AREA. DESPITE THE CLIMATOLOGICAL ABILITY FOR WINDS TO
DECOUPLE IN THE WFO PAH FORECAST AREA...THE ENTIRE SUITE OF HIGH
RESOLUTION AND STATISTICAL NUMERICAL GUIDANCE IS LEADING CREDENCE
THAT THE WIND GRADIENT WILL REMAIN STRONG ENOUGH TO KEEP MIXING IN
PLACE FOR MOST LOCATIONS. THIS WOULD LIMIT THE DEVELOPMENT OF
FROST TO THOSE SITES THAT ARE NORMALLY WELL PROTECTED FROM WINDS.
HOWEVER...GIVE THE UNCERTAINTY ON THE CONSISTENCY OF WINDS SPEEDS
OVER THE ENTIRE PERIOD FROM MIDNIGHT THROUGH 8 AM CDT...A SPECIAL
WEATHER STATEMENT HAS BEEN ISSUED FOR THE ENTIRE FORECAST AREA. AN
ADDITIONAL MENTION WILL BE MADE IN THE HAZARDOUS WEATHER OUTLOOK
THIS AFTERNOON. THE EVENING FORECAST WILL NEED TO MONITOR WINDS
THIS EVENING...SHOULD THE GRADIENT RELAX FASTER THAN ANTICIPATED
AT THIS TIME.
THE CURRENT CONVECTION OVER THE WFO PAH FORECAST AREA SHOULD
LESSEN WITH THE LOSS OF INSOLATION AND TRANSLATION OF THE PRIMARY
CHANNELED VORTICITY OUT OF THE AREA TONIGHT. THE POTENTIAL FOR ANY
FURTHER ENHANCED CONVECTION /THUNDERSTORMS/ OVER SOUTHEAST MO/WEST
KENTUCKY SHOULD DROP OFF MARKEDLY BEFORE 5 PM CDT...WITH ANY
SHOWER ACTIVITY DIMINISHING BEFORE 8 PM CDT. THE 3KM HRRR AND 12KM
NAM-WRF DID A FAIRLY GOOD JOB OF DEPICTING THE
LOCATION/COVERAGE/INTENSITY OF THE CONVECTION TODAY AND WAS USED
AS A TEMPLATE IN PREPARING THE GRIDDED FORECAST UPDATES.
THERE WILL STILL BE SOME MINOR COLD AIR ADVECTION AND LIFT IN THE
DEPARTING CYCLONIC FLOW ON MONDAY...SO COLLABORATED WITH WFO ST.
LOUIS IN BEING MORE AGGRESSIVE WITH DIURNALLY-BASED COLD AIR
STRATOCUMULUS DEVELOPMENT DURING THE LATE MORNING AND AFTERNOON HOURS.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 305 PM CDT SUN APR 22 2012
NOT MUCH CHANGE TO THE EXTENDED. PREFER TO STAY THE COURSE WITH ONLY
MINOR MODIFICATIONS VS. WHAT SOME OF THE NEW GUIDANCE...IN PARTICULAR
THE GFS IS DEPICTING. IT HAS SLOWED THE FRONTAL PASSAGE CONSIDERABLY
WEDNESDAY NIGHT THROUGH THURSDAY. IT HANGS THE FRONT UP ACROSS THE
AREA AND SUGGESTS THE CHANCE OF CONVECTION WILL NOT CLEAR THE AREA.
THIS IS IN STARK CONTRAST TO WHAT IT WAS SHOWING PRIOR. THE OTHER
MODELS CONTINUE TO PUSH THE FRONT ON THROUGH...ALTHOUGH PERHAPS NOT
QUITE AS FAR TO THE SOUTH AS PREVIOUSLY ADVERTISED. THE NEW 12Z
ECMWF CONTINUES TO PUSH THE FRONT ON THROUGH WITH TIME. BEST CHANCE
POPS WILL CONTINUE TO BE WEDNESDAY NIGHT IN CLOSE PROXIMITY TO THE
FRONT. SHRA/TSRA HIGH CHANCE TO LOW END LIKELY POPS WILL BE USED.
THE CHANCE OF ISOLATED SEVERE IS STILL UP FOR DEBATE AT THIS POINT AS
THE PARAMETERS ARE MARGINAL. HARD TO RULE OUT LOW END CHANCE POPS
FROM LATE FRIDAY ON INTO THE WEEKEND GIVEN THE UNSETTLED LOOK TO THE
PATTERN...ONCE THE MID LEVEL RIDGE PASSES BY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 121 PM CDT SUN APR 22 2012
MAIN CHALLENGE WITH THE 18Z SUNDAY ROUTINE TAF ISSUANCE WAS THE TIMING
OF THE THE MEAN CLOUD COVERAGE/HEIGHTS ASSOCIATED WITH THE RAPID
SOUTHEAST MOVING SYSTEM THROUGH THE WFO PAH TAF SITES. ATTEMPTED
TO KEEP VFR CEILINGS AS THE PREDOMINANT CLOUD COVER THROUGH THE
REMAINDER OF THIS AFTERNOON FOR KCGI/KPAH...AND THIS EVENING FOR
KEVV/KOWB. ALSO...WITH THIS PACKAGE...ATTEMPTED TO PIN DOWN THE
MOST LIKELY TIME FOR CONVECTIVE SHOWER ACTIVITY IN AND NEAR EACH
TAF SITE...BASED ON CURRENT AND PROJECTED TRENDS THIS AFTERNOON.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
SHORT TERM...SMITH
LONG TERM....CTN
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
133 AM EDT SUN APR 22 2012
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 425 PM EDT SAT APR 21 2012
THE AMPLIFYING RIDGE OVER THE WRN CONUS AND THE STRENGTHENING UPPER
LOW OVER THE GULF WILL LEAD TO THE NRN STREAM TROUGH AMPLIFYING
OVER THE UPPER GREAT LKS. THIS WILL ALLOW THE NRN STREAM JET TO
STRETCH FROM SASK/ALBERTA SE INTO THE SE CONUS. WITH THIS
AMPLIFICATION AND THE SHORTWAVE NOW PUSHING INTO WRN MN AND SE INTO
ILLINOIS TONIGHT...EXPECT THE SFC LOW AND ASSOCIATED WARM FRONT PCPN
OVER WRN MN TO FOCUS FARTHER S...WHILE H850-700 WAA PCPN OVER
NERN MN WILL DIMINISH WITH THE WEAKENING LOW/WAA. THIS REFOCUSING TO
THE SE IS SEEN WELL IN THE NAM/GFS H850-500 Q-VECTOR CONV
AREAS...ALONG WITH THEIR MOISTURE FIELDS. 17Z RUC ALSO HAS A GOOD
HANDLE ON THE PCPN IN THE SHORT TERM AND WILL USE THOSE FOR THE
EVOLUTION THIS EVENING. ALL IN ALL...EXPECT THE PCPN TO STAY JUST W
OF THE CWA...DUE TO THE DRY SFC TO H850 AIR ROTATING AROUND THE
HIGH IN ONTARIO. BUT STILL EXPECT MID/HIGH CLOUDS TO CONTINUE TO
SLOWLY PUSH E OVER THE WRN THIRD OF THE CWA AND REMAIN THROUGH THE
NIGHT. ELSEWHERE...EXPECT THE DIURNAL CU TO DISSIPATE AND A MOSTLY
CLEAR NIGHT IS EXPECTED.
THE EXACT LOCATION OF THE CLOUDS WILL LARGELY DETERMINE TEMPS OVER
THE WRN HALF OF THE CWA. DID KEEP LOWS UP SOME WITH THE EXPECTED
CLOUD COVER...TOWARDS FREEZING OVER THE FAR W AND MID/UPPER 20S
TOWARDS THE W-CNTRL. LIGHT WINDS OVER THE CNTRL/EAST AND PWAT VALUES
OF 35-40 PERCENT OF NORMAL WILL LEAD TO A GOOD RADIATIONAL COOLING
NIGHT. HAVE LOWERED TEMPS OVER THE E BASED OFF LOWS LAST NIGHT AND
AFTN DEWPOINTS FALLING INTO THE UPPER TEENS AND LOWER 20S. WENT A
FEW DEGREES BELOW GUIDANCE OVER THE INTERIOR COLD SPOTS...MAINLY IN
THE LOWER 20S.
SUNDAY...SFC LOW WILL MOVE OUT OF THE GULF ON SUN AND UP THE
ATLANTIC SEABOARD...WHILE THE UPPER RIDGE CONTINUES TO AMPLIFY OVER
THE WRN CONUS AND CANADIAN ROCKIES. THIS WILL KEEP HIGH PRESSURE
OVER THE UPPER GREAT LKS REGION...ALTHOUGH IT WILL GRADUALLY WEAKEN
AS IT FOCUSES OVER WRN LK SUPERIOR. NAM/GFS/ECMWF SHOWING WEAK
SHORTWAVE AND PV LOBE MOVING ACROSS THE AREA DURING THE
MORNING...BUT DRY LOW LEVELS WILL LIMIT PCPN CHANCES OVER THE W.
MODELS CONSISTENT ON H850-500 MOISTURE TO BE STUCK OVER THE WRN
THIRD OF THE CWA TOMORROW...WHICH WITH LIGHT WINDS AT THAT
LEVEL...WENT WITH PARTLY-MOSTLY CLOUDY SKIES. ELSEWHERE...LLVLS ARE
STILL FAIRLY DRY WITH THE HIGH PRESSURE RIDGE...SO EXPECT A MOSTLY
SUNNY SKY. WITH THE SUN OVER THE CNTRL/EAST...EXPECT MIXING TO H800
AND HAVE BUMPED TEMPS UP A DEGREE OR TWO FROM THE GOING
FORECAST...WITH LOW 50S AWAY FROM LK SUPERIOR INFLUENCES. THE LIGHT
NRLY FLOW SHOULD ALLOW THE LK SUPERIOR BREEZE TO DOMINATE AND BRING
SLIGHTLY COOLER TEMPS NEAR LK SUPERIOR THROUGH THE AFTN.
SURPRISINGLY...MODELS NOT PICKING UP ON MUCH COOL DOWN UNTIL AFTER
21Z...SO WILL FOLLOW THAT TREND NEAR LK SUPERIOR FOR NOW.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 425 PM EDT SAT APR 21 2012
MEDIUM RANGE GUIDANCE IS IN GOOD AGREEMENT ON THE BIG PICTURE FOR
THE NEXT 7 DAYS AS PATTERN WILL FEATURE A WRN NAMERICA RIDGE AND
ERN TROF...RESULTING IN NW FLOW DOMINATING THE UPPER GREAT LAKES
REGION. ERN TROF WILL BE MOST AMPLIFIED MON/TUE...AND WRN RIDGE WILL
BEGIN TO DRIFT E DURING THE LAST HALF OF THE WEEK WITH AXIS REACHING
THE MISSISSIPPI VALLEY TO MANITOBA BY SAT. OVERALL...THIS IS A DRY
PATTERN FOR THE FCST AREA. PCPN CHANCES WILL BE LIMITED...AND IF
ANY PCPN OCCURS...IT WILL LIKELY BE LIGHT. NW FLOW SHOULD KEEP TEMPS
ON THE COOLER SIDE OF NORMAL AND PROBABLY TREND MORE BLO NORMAL
LATER IN THE WEEK AS ENERGY DROPPING INTO ERN TROF USHERS COLDER AIR
INTO THE UPPER LAKES. AFTN TEMPS NEAR LAKE SUPERIOR WILL BE CHILLY
WITH ONSHORE WINDS EVERY DAY.
BEGINNING SUN NIGHT THRU TUE...WITHIN THE DEEP ERN TROF...A
MID/UPPER LEVEL LOW WILL BE LIFTING N THRU THE CNTRL APPALACHIANS...
REACHING WRN NY EARLY TUE AND SW QUEBEC TUE EVENING. MEDIUM RANGE
GUIDANCE CONTINUES TO KEEP THIS SYSTEM FAR ENOUGH E SO THAT ITS
DEFORMATION PCPN SHIELD WILL NOT AFFECT THE FCST AREA. THREAT OF ANY
PCPN WOULD COME FROM SHORTWAVES DROPPING THRU THE AREA UNDER NW FLOW
AS THERMAL GRADIENT WILL BE TIGHTENING TOWARD THE UPPER LAKES MON
AND ESPECIALLY TUE. THE GFS/GLOBAL GEM ARE A LITTLE FARTHER E WITH
THE TIGHTER THERMAL GRADIENT THAN THE ECMWF. AS A RESULT...
GFS/GLOBAL GEM HAVE PCPN STREAKING ACROSS MAINLY WRN UPPER MI TUE.
AT THIS POINT...WILL CARRY DRY WEATHER SUN NIGHT THRU MON NIGHT THEN
MAINTAIN SLIGHT CHC POPS LATER TUE/TUE NIGHT OVER ALL BUT THE E.
TIMING/TRACKS OF SHORTWAVES DROPPING INTO THE ERN TROF REMAIN
UNCERTAIN MIDWEEK. THE LAST SEVERAL RUNS OF THE ECMWF HAD BEEN
INSISTENT ON DROPPING A STRONG SHORTWAVE INTO THE UPPER LAKES LATE
THU...BUT THE 12Z RUN IS BEGINNING TO TREND TOWARD THE FASTER
GFS/GLOBAL GEM IDEA. WHETHER THIS WAVE CAN LINK UP/DRAW TIGHT
THERMAL GRADIENT FARTHER NE LIKE THE GFS/GLOBAL GEM TO RESULT IN A
PERIOD OF PCPN ACROSS THE FCST AREA INTO WED REMAINS TO BE SEEN.
BEHIND THE WAVE...850MB TEMPS COULD FALL TO AROUND -10C THU/EARLY
FRI. MIGHT BE ENOUGH FOR A LITTLE LIGHT LES AT NIGHT/EARLY MORNING
IF AIRMASS IS NOT TOO DRY.
FRI INTO SAT...WITH MID/UPPER LEVEL RIDGE MOVING CLOSER TO THE UPPER
LAKES...ASSOCIATED SFC HIGH PRES WILL DOMINATE THE AREA. THIS WILL
KEEP DRY WEATHER INTO THE FIRST HALF OF THE WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 132 AM EDT SUN APR 22 2012
VFR CONDITIONS EXPECTED FOR THE TAF SITES THROUGH THE PERIOD...AS A
HIGH IN ONTARIO PUSHES DRY LOW LEVEL AIR INTO UPPER MICHIGAN.
MOISTURE FROM LOW CURRENTLY CENTERED OVER NW MN WILL BRUSH KIWD AND
POTENTIALLY KCMX THROUGH SUN...AS IT WEAKENS AND SLIDES SE THROUGH
SOUTHERN MN.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 425 PM EDT SAT APR 21 2012
HIGH PRESSURE NEAR HUDSON BAY WILL KEEP LIGHT NORTHERLY WINDS OVER
MUCH OF LAKE SUPERIOR. A LOW PRESSURE SYSTEM OVER ERN ND IS EXPECTED
TO WEAKEN WHILE QUICKLY SLIDING SE TONIGHT. THIS WILL DIMINISH THE
NE WINDS OF 20-25KTS OVER FAR WRN LAKE SUPERIOR. EXPECT NORTHERLY
WINDS TO REMAIN BELOW 25KTS THROUGH THE FIRST PART OF NEXT WEEK...AS
A LOW PRESSURE SYSTEM MOVES UP THE ATLANTIC SEABOARD TOMORROW AND
INTO QUEBEC BY TUESDAY. COLDER AIR FILTERING INTO THE AREA TOWARDS
MID WEEK COULD LEAD TO SOME STRONGER NORTHERLY WINDS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...ROLFSON
AVIATION...07
MARINE...SRF
AREA FORECAST DISCUSSION
NWS DULUTH MN
1246 PM CDT SUN APR 22 2012
.AVIATION...18Z TAF ISSUANCE...
MVFR AND LOW END VFR CIGS WILL LINGER THROUGH THIS AFTERNOON OVER
NORTHEASTERN MINNESOTA AND NORTHWESTERN WISCONSIN TODAY IN THE
WAKE OF A LOW PRESSURE SYSTEM. THERE MAY BE SHORT PERIODS OF IFR
CIGS. AT KDLH/KHIB/KBRD. SCATTERED RAIN AND SNOW SHOWERS WILL
AFFECT KDLH AND KBRD THROUGH AT LEAST THE EARLY AFTERNOON...BUT
THE PCPN SHOULD BEGIN TO DISSIPATE MID AFTERNOON. THE CIGS SHOULD
LIFT AND BEGIN TO SCATTER MID TO LATE AFTERNOON...WITH KINL
CLEARING FIRST. VFR CIGS ARE EXPECTED BY MID EVENING AS WEAK HIGH
PRESSURE ASSERTS ITSELF OVER THE REGION. MID TO HIGH CLOUDS WILL
FILL IN LATER TONIGHT AND TOMORROW MORNING...WITH LIGHT
SOUTHWESTERLY WINDS DEVELOPING AROUND DAWN.
&&
.PREV DISCUSSION... /ISSUED 1102 AM CDT SUN APR 22 2012/
UPDATE...MAIN ISSUE TODAY IS DISSIPATION RATE OF LARGE STRATUS
CLOUD FIELD LEFT IN WAKE OF DEPARTED SYSTEM. RUC13 85/70H LAYER
IS 90 PERCENT OR MORE OVER MOST OF ARROWHEAD/RANGE/BRD LAKES/TWIN
PORTS REGION. EROSION OF CLOUD DECK SHOULD OCCUR OVER NWRN CWA
SLOWLY TODAY ALTHOUGH INSTABILITY CU MAY REDEVELOP IN AFTERNOON
SUNSHINE. DEEP LAYER MOISTURE SHOULD ADVECT SLOWLY EAST INTO
WISCONSIN BY LATE AFTN. VERY LITTLE FORCING EVIDENT AT THIS TIME
AND 88D RETURNS HAVE BEEN DECREASING WITH TIME THIS MORNING. PTYPE
PLAYING THE BDRY LYR MERRY GO ROUND WITH RAIN/SNOW AT TIMES ACROSS
NRN MN ZONES. WILL KEEP IDEA THAT EVENTUALLY ANYTHING DESCENDING
THIS AFTN FROM THE CLOUDS WILL BE LIQUID.
PREV DISCUSSION... /ISSUED 408 AM CDT SUN APR 22 2012/
SHORT TERM...LATEST REGIONAL SURFACE ANALYSIS SHOWS THE DEPARTING
LOW PRESSURE SYSTEM NOW OVER IOWA EARLY THIS MORNING...WITH A
WEAK INVERTED TROUGH EXTENDING NORTH OF THE LOW OVER MINNESOTA TO
NEAR PARK RAPIDS. THERE IS ALSO A RIDGE OF HIGH PRESSURE EXTENDING
FROM NWRN ONTARIO SWWD ACROSS NWRN MN AND THE DAKOTAS...WHICH IS
SLOWLY BUILDING SWRD. HOWEVER WATER VAPOR SATELLITE IMAGERY
SHOWS A SECOND UPPER LEVEL VORTMAX OVER THE BORDER REGION...WHICH
IS PRODUCING ENOUGH LIFT FOR AREAS OF LIGHT PRECIP...MAINLY IN THE
FORM OF SNOW...ACROSS AREAS NORTHWEST OF THE IRON RANGE. FARTHER
SOUTH ACROSS THE BRAINERD LAKES REGION AND SAINT CROIX RIVER
VALLEY...AREAS OF LIGHT RAIN AND DRIZZLE CONTINUE TO FALL.
DUE TO THE WEAK SFC FEATURES COMBINED WITH ABUNDANT LOW LEVEL
MOISTURE...THE NWP MODELS SHOW SOME DIFFERENCES IN HOW THE THESE
AREAS OF PRECIP WILL EVOLVE ACROSS OUR CWA TODAY. HOWEVER THE
GENERALLY PATTERN IS TO GRADUALLY MOVE THE MAIN AXIS OF PRECIP
GRADUALLY EWD...WITH THE PRECIP COVERAGE DECREASING DURING THE
DAY. BY THIS EVENING...MAINLY DRY CONDITIONS ARE EXPECTED AS THE
RIDGE OF HIGH PRESSURE MOVES OVER THE NORTHLAND AND DRIER AIR
SPREADS SEWD ACROSS THE FCST AREA. THE RIDGE WILL REMAIN OVER THE
UPPER MIDWEST ON MONDAY AS A STRONG STORM SYSTEM LIFTS NEWD
ACROSS THE ERN THIRD OF THE COUNTRY. TEMPERATURES WILL MODERATE
TODAY...ALTHOUGH THE CLOUD COVER WILL KEEP TEMPS AT BELOW NORMAL
LEVELS. WARMER TEMPS ARE EXPECTED ON MONDAY AS SKIES BECOME
PARTLY CLOUDY AND WINDS TURN OUT OF A LIGHT WRLY DIRECTION.
LONG TERM...MONDAY NIGHT THROUGH SATURDAY.
AN UPPER LEVEL RIDGE WILL EXTEND NORTH FROM NEW MEXICO INTO THE
MT/SK EARLY IN THE PERIOD...WITH AN UPPER LOW OVER THE EASTERN
GREAT LAKES. THE MODELS ARE IN GOOD AGREEMENT ON THIS. HOWEVER...A
SURFACE LOW OVER THE NORTHERN PLAINS IS HANDLED QUITE DIFFERENTLY
BETWEEN THE GFS/ECMWF. THE GFS IS FASTER AND A BIT DEEPER WITH THE
LOW AND TAKES A FAR DIFFERENT TRACK COMPARED WITH THE ECMWF/GEM.
WE WENT CLOSER TO THE ECMWF. WE HAVE CHANCES FOR RAIN MONDAY NIGHT
INTO WEDNESDAY. A NICE BAROCLINIC ZONE IS ALSO FORECAST TO BE OVER
THE CWA...WITH THE MODELS SHOWING SOME FGEN DURING THIS PERIOD AS
WELL.
AS THE UPPER RIDGE MOVES EAST MID-LATE WEEK...A STRONG SURFACE HIGH
WILL DEVELOP BETWEEN THE UPPER RIDGE AND A TROUGH/LOW OVER QUEBEC/NE
CONUS. THIS HIGH WILL BRING IN SOME DRY AIR FOR THURSDAY THROUGH
FRIDAY NIGHT.
THE UPPER LEVEL RIDGE WILL PASS EAST OF THE REGION OVER THE
WEEKEND...ALLOWING A TROUGH TO BRING A CHANCE FOR PRECIP TO THE
NORTHLAND. THE GFS IS QUICKER BRINGING MOISTURE BACK INTO THE
NORTHLAND...AND WE DELAYED THE ARRIVAL IN THE NORTHEASTERN HALF OF
THE CWA UNTIL SATURDAY NIGHT.
WE EXPECT TEMPS FROM THE UPPER FIFTIES TO UPPER SIXTIES
TUESDAY...EXCEPT COOLER READING AROUND LAKE SUPERIOR...WITH MAINLY
FIFTIES FOR THE REMAINDER OF THE PERIOD. LOWS THURSDAY NIGHT AND
FRIDAY NIGHT COULD BE QUITE COOL WITH THE HIGH CREATING MAINLY CLEAR
SKIES AND LIGHT WINDS.
&&
.POINT TEMPS/POPS...
DLH 45 32 60 38 / 40 10 10 10
INL 51 29 60 35 / 40 10 10 20
BRD 51 32 63 39 / 50 10 0 10
HYR 52 30 60 36 / 30 10 0 10
ASX 49 32 59 35 / 20 10 0 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...CANNON
LONG TERM....GROCHOCINSKI
AVIATION...GROCHOCINSKI
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1102 AM CDT SUN APR 22 2012
.UPDATE...MAIN ISSUE TODAY IS DISSIPATION RATE OF LARGE STRATUS
CLOUD FIELD LEFT IN WAKE OF DEPARTED SYSTEM. RUC13 85/70H LAYER
IS 90 PERCENT OR MORE OVER MOST OF ARROWHEAD/RANGE/BRD LAKES/TWIN
PORTS REGION. EROSION OF CLOUD DECK SHOULD OCCUR OVER NWRN CWA
SLOWLY TODAY ALTHOUGH INSTABILITY CU MAY REDEVELOP IN AFTERNOON
SUNSHINE. DEEP LAYER MOISTURE SHOULD ADVECT SLOWLY EAST INTO
WISCONSIN BY LATE AFTN. VERY LITTLE FORCING EVIDENT AT THIS TIME
AND 88D RETURNS HAVE BEEN DECREASING WITH TIME THIS MORNING. PTYPE
PLAYING THE BDRY LYR MERRY GO ROUND WITH RAIN/SNOW AT TIMES ACROSS
NRN MN ZONES. WILL KEEP IDEA THAT EVENTUALLY ANYTHING DESCENDING
THIS AFTN FROM THE CLOUDS WILL BE LIQUID.
&&
.PREV DISCUSSION... /ISSUED 625 AM CDT SUN APR 22 2012/
AVIATION...12Z TAFS
LIGHT RAIN OR SNOW CONTINUED OVER WESTERN AND NORTHERN
AREAS...IMPACTING KBRD...AND AREAS JUST NORTH OF KHIB. SOME
LOCALLY VERY DRY LOW LEVEL AIR COVERED THE NORTH SHORE DOWN INTO
KDLH...AND ALLOWED CEILINGS TO REMAIN VFR AND KEEPING ANY PRECIP
AWAY. MVFR CEILINGS WERE OCCURRING FROM KBRD...NORTH AND EAST INTO
FAR NORTHERN MINNESOTA. THESE CEILINGS WILL CONTINUE THIS
MORNING...POSSIBLY OCCURRING AT KHIB/KDLH AS WELL. THE MVFR
CEILINGS WILL RISE THIS AFTERNOON...WITH THE CLOUDS DIMINISHING IN
SPOTS. HOWEVER...SOUNDINGS SUGGEST ANY CLEAR AREAS WILL SEE
CUMULUS DEVELOP WITH HEATING OF THE DAY...WITH CEILINGS FROM
2500-4000FT DEPENDING ON LOW LEVEL MOISTURE.
CLOUDS WILL DIMINISH FURTHER THIS EVENING...THEN INCREASE AGAIN LATE
OVER THE FAR NORTH.
PREV DISCUSSION... /ISSUED 408 AM CDT SUN APR 22 2012/
SHORT TERM...LATEST REGIONAL SURFACE ANALYSIS SHOWS THE DEPARTING
LOW PRESSURE SYSTEM NOW OVER IOWA EARLY THIS MORNING...WITH A
WEAK INVERTED TROUGH EXTENDING NORTH OF THE LOW OVER MINNESOTA TO
NEAR PARK RAPIDS. THERE IS ALSO A RIDGE OF HIGH PRESSURE EXTENDING
FROM NWRN ONTARIO SWWD ACROSS NWRN MN AND THE DAKOTAS...WHICH IS
SLOWLY BUILDING SWRD. HOWEVER WATER VAPOR SATELLITE IMAGERY
SHOWS A SECOND UPPER LEVEL VORTMAX OVER THE BORDER REGION...WHICH
IS PRODUCING ENOUGH LIFT FOR AREAS OF LIGHT PRECIP...MAINLY IN THE
FORM OF SNOW...ACROSS AREAS NORTHWEST OF THE IRON RANGE. FARTHER
SOUTH ACROSS THE BRAINERD LAKES REGION AND SAINT CROIX RIVER
VALLEY...AREAS OF LIGHT RAIN AND DRIZZLE CONTINUE TO FALL.
DUE TO THE WEAK SFC FEATURES COMBINED WITH ABUNDANT LOW LEVEL
MOISTURE...THE NWP MODELS SHOW SOME DIFFERENCES IN HOW THE THESE
AREAS OF PRECIP WILL EVOLVE ACROSS OUR CWA TODAY. HOWEVER THE
GENERALLY PATTERN IS TO GRADUALLY MOVE THE MAIN AXIS OF PRECIP
GRADUALLY EWD...WITH THE PRECIP COVERAGE DECREASING DURING THE
DAY. BY THIS EVENING...MAINLY DRY CONDITIONS ARE EXPECTED AS THE
RIDGE OF HIGH PRESSURE MOVES OVER THE NORTHLAND AND DRIER AIR
SPREADS SEWD ACROSS THE FCST AREA. THE RIDGE WILL REMAIN OVER THE
UPPER MIDWEST ON MONDAY AS A STRONG STORM SYSTEM LIFTS NEWD
ACROSS THE ERN THIRD OF THE COUNTRY. TEMPERATURES WILL MODERATE
TODAY...ALTHOUGH THE CLOUD COVER WILL KEEP TEMPS AT BELOW NORMAL
LEVELS. WARMER TEMPS ARE EXPECTED ON MONDAY AS SKIES BECOME
PARTLY CLOUDY AND WINDS TURN OUT OF A LIGHT WRLY DIRECTION.
LONG TERM...MONDAY NIGHT THROUGH SATURDAY.
AN UPPER LEVEL RIDGE WILL EXTEND NORTH FROM NEW MEXICO INTO THE
MT/SK EARLY IN THE PERIOD...WITH AN UPPER LOW OVER THE EASTERN
GREAT LAKES. THE MODELS ARE IN GOOD AGREEMENT ON THIS. HOWEVER...A
SURFACE LOW OVER THE NORTHERN PLAINS IS HANDLED QUITE DIFFERENTLY
BETWEEN THE GFS/ECMWF. THE GFS IS FASTER AND A BIT DEEPER WITH THE
LOW AND TAKES A FAR DIFFERENT TRACK COMPARED WITH THE ECMWF/GEM.
WE WENT CLOSER TO THE ECMWF. WE HAVE CHANCES FOR RAIN MONDAY NIGHT
INTO WEDNESDAY. A NICE BAROCLINIC ZONE IS ALSO FORECAST TO BE OVER
THE CWA...WITH THE MODELS SHOWING SOME FGEN DURING THIS PERIOD AS
WELL.
AS THE UPPER RIDGE MOVES EAST MID-LATE WEEK...A STRONG SURFACE HIGH
WILL DEVELOP BETWEEN THE UPPER RIDGE AND A TROUGH/LOW OVER QUEBEC/NE
CONUS. THIS HIGH WILL BRING IN SOME DRY AIR FOR THURSDAY THROUGH
FRIDAY NIGHT.
THE UPPER LEVEL RIDGE WILL PASS EAST OF THE REGION OVER THE
WEEKEND...ALLOWING A TROUGH TO BRING A CHANCE FOR PRECIP TO THE
NORTHLAND. THE GFS IS QUICKER BRINGING MOISTURE BACK INTO THE
NORTHLAND...AND WE DELAYED THE ARRIVAL IN THE NORTHEASTERN HALF OF
THE CWA UNTIL SATURDAY NIGHT.
WE EXPECT TEMPS FROM THE UPPER FIFTIES TO UPPER SIXTIES
TUESDAY...EXCEPT COOLER READING AROUND LAKE SUPERIOR...WITH MAINLY
FIFTIES FOR THE REMAINDER OF THE PERIOD. LOWS THURSDAY NIGHT AND
FRIDAY NIGHT COULD BE QUITE COOL WITH THE HIGH CREATING MAINLY CLEAR
SKIES AND LIGHT WINDS.
&&
.POINT TEMPS/POPS...
DLH 45 32 60 39 / 40 10 10 10
INL 51 29 62 36 / 40 10 10 20
BRD 51 32 64 40 / 50 10 0 10
HYR 52 30 62 37 / 30 10 0 10
ASX 49 32 58 36 / 20 10 0 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...CANNON
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1010 PM EDT MON APR 23 2012
.SYNOPSIS...
A STRONG LOW PRESSURE SYSTEM WILL CONTINUE TO DRIFT NORTHWARD OVER
THE NORTHERN MID ATLANTIC THROUGH TONIGHT. THE ACCOMPANYING UPPER
LEVEL TROUGH WILL REMAIN OVER OUR REGION THROUGH TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 10 PM MONDAY...
DEEP LOW PRESSURE OVER THE NORTHEAST US IS EXPECTED TO BECOME
VERTICALLY STACKED BY DAYBREAK.
SCATTERED SHOWERS SEEN EARLIER THIS EVENING HAVE LONG ENDED AND
SOME BREAKS HAVE STARTED TO DEVELOP IN THE RATHER EXTENSIVE CLOUD
SHIELD AS CENTRAL NC WILL SEE A PERIOD OF SUBSIDENCE OVERNIGHT
BETWEEN THE NEXT SUBSTANTIAL VORT MAX PIVOTS ACROSS THE AREA. THIS
SHOULD RESULT IN A CONTINUED DECREASE IN CLOUDS WITH MOSTLY CLEAR
SKIES EXPECTED BY DAYBREAK.
WINDS APPEAR AS IF THEY WILL REMAIN UP OVERNIGHT WITH LATEST SFC
ANALYSIS AND RUC FORECAST MSL PRESSURE CONTINUING TO DEPICT
A GOOD 4 TO 5 MB PRESSURE GRADIENT OVER THE AREA TONIGHT...WHICH
SHOULD KEEP WINDS STIRRING BETWEEN 4 TO 6 KTS. THIS MIXING COUPLED
WITH GRADUAL CLEARING SHOULD RESULT IN A SLOW TEMPERATURE FALL
OVERNIGHT WITH TEMPERATURES MOSTLY IN THE UPPER 30S TO LOWER 40S. A
FEW OUTLYING/SHELTERED AREAS COULD FALL INTO THE MID 30S(34-35)FOR A
BRIEF...ONE TO TWO HOUR WINDOW JUST BEFORE DAYBREAK...WHICH
COULD RESULT IN SOME VERY PATCHY FROST AT BEST. GIVEN THE
UNFAVORABLE CONDITIONS AND THE EXPECTED LIMITED NATURE IN FROST
DEVELOPMENT...WILL CONTINUE TO MENTION PATCHY FROST IN
HWO ONLY...WITH NO PLANS ON ISSUING AN ADVISORY.
&&
.SHORT TERM /TUESDAY AND TUESDAY NIGHT/...
AS OF 310 PM MONDAY...
ANOTHER VORT MAXIMUM IN NW FLOW BEHIND DEPARTING UPPER LEVEL LOW
WILL APPROACH OUR REGION TUESDAY MORNING AND AFFECT OUR AREA TUESDAY
AFTERNOON-EVENING. MODEL GUIDANCE HAS COME INTO BETTER CONSENSUS AS
FAR AS PATH AND TIMING. ASSOCIATED MID LEVEL COOL POOL WITH THIS
FEATURE WILL YIELD MID LEVEL LAPSE RATES 7-8 DEGREE C/KM. IF SHOWERS
OBTAIN SUFFICIENT DEPTH...MAY SEE A FEW LIGHTNING STRIKES AND SMALL
HAIL WITH THE STRONGER CORES. ALSO INVERTED VEE SOUNDINGS SUGGEST
POTENTIAL FOR GUSTY WINDS...THOUGH WIND PROFILE THROUGH THE COLUMN
(BELOW 12K FT) AOB 25KTS. THUS GUSTS SHOULD BE BELOW SEVERE CRITERIA.
SHOULD SEE DECENT DISPLAY OF SUN THROUGH THE THE MORNING AND
POSSIBLY EARLY AFTERNOON HOURS BEFORE CLOUDS INCREASE THICKEN.
THICKNESSES TUESDAY RECOVER ABOUT 15M FROM TODAY`S UNSEASONABLY LOW
VALUES (ABOUT 40M BELOW NORMAL). STILL...MAX TEMPS WILL AVERAGE 10
DEGREES BE NORMAL IN THE MID-UPPER 60S. IF CLOUDS DEVELOP SOONER
THAN EXPECTED....MAX TEMPS MAY END UP BEING 3-4 DEGREES
COOLER...ESPECIALLY SW HALF.
ANOTHER BREEZY DAY EXPECTED TUESDAY DUE TO DEEP LOW OVER THE
EASTERN LAKES/SOUTHERN NEW ENGLAND AND HIGH PRESSURE OVER THE LOWER
MS VALLEY. EXPECT WLY WINDS 10-15 MPH WITH GUSTS AROUND 25 MPH.
WINDS WILL SUBSIDE A BIT IN THE AFTERNOON AS CLOUD COVERAGE
INCREASES/THICKENS.
TUESDAY NIGHT...VORT MAX WILL SLIDE JUST SW OF OUR REGION IN THE
EVENING...ITS INFLUENCE WANING BY MIDNIGHT. THIS SHOULD LEAD TO
DECREASING CLOUD COVERAGE. MIN TEMPS UPPER 30S NE TO THE LOW-MID
40S WEST AND SOUTH.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
AS OF 300 PM MONDAY...
WITH SURFACE HIGH PRESSURE CENTERED OVER FL 12Z WEDNESDAY AND
RIDGING INTO NC...EXPECT WEDNESDAY TO REMAIN DRY FOR THE MOST PART
WITH SOME SHOWERS APPROACHING FROM THE WEST WEDNESDAY AND INTO
WEDNESDAY NIGHT. HIGH TEMPS WEDNESDAY RANGING FROM THE UPPER 60S N
TO MID 70S SW.
MODEL SOLUTIONS ARE STILL NOT IN VERY GOOD AGREEMENT WITH THE
POTENTIAL SHORT WAVES IMPACTING NC OVER THE REMAINDER OF THE
FORECAST PERIOD. THAT BEING SAID...BOTH THE GFS AND ECMWF INDICATE
THE SHORT WAVE MOVING OVER NC THURSDAY NIGHT SO THERE IS CONFIDENCE
THAT AT LEAST THE NORTHERN HALF OF THE AREA WILL GET SOME PRECIP.
HAVE CONTINUED CHANCE POPS THURSDAY AFTERNOON AND THURSDAY NIGHT
WITH THE CHANCE FOR SOME ISOLATED THUNDER THURSDAY EVENING. LOWS
WEDNESDAY NIGHT AND THURSDAY NIGHT IN THE MID TO UPPER 50S...WITH
HIGHS THURSDAY IN THE UPPER 70S NORTH TO LOW 80S SOUTH. EXPECT WINDS
TO BE 10-15 KTS THURSDAY AFTERNOON.
AS STATED IN THE PREVIOUS DISCUSSION...FRIDAYS FORECAST WILL BE
DETERMINED BY HOW FAR SOUTH THE EAST WEST FRONT TRAILING AN OFFSHORE
SURFACE LOW WILL PUSH... AND IF HIGH PRESSURE WILL BE ABLE TO SPILL
OVER THE MID ATLANTIC MOUNTAINS AND SOUTH... OR REMAIN MORE CONFINED
WEST OF THE APPALACHIANS. ALTHOUGH CONFIDENCE IS NOT HIGH...HAVE
LEANED MORE TOWARD THE GFS SOLUTIONS FOR FRIDAY AND FRIDAY NIGHT
WHICH DEPICT A SFC LOW DEVELOPING OVER NC FRIDAY NIGHT. AS
SUCH...HAVE LEFT THE CHANCE FOR PRECIP ACROSS THE NE WITH SLIGHT
CHANCE ELSEWHERE. HIGHS FRIDAY IN THE LOW TO MID 70S AND LOWS IN THE
UPPER 40S TO MID 50S...HOWEVER THIS IS DEPENDENT ON WHETHER OR NOT
PRECIP DOES IN FACT DEVELOP AND ARE SUBJECT TO CHANGE.
HIGH PRESSURE SHOULD BUILD IN FOR SATURDAY AND SUNDAY BEFORE THE
NEXT SYSTEM APPROACHES FROM THE NW SUNDAY NIGHT. HAVE KEPT THE
FORECAST DRY THROUGH MONDAY. GIVEN THE DIFFERENCES IN MODEL
SOLUTIONS REGARDING THE TIMING OF THE NEXT SYSTEM PRECIP IS POSSIBLE
SUNDAY NIGHT INTO MONDAY...HOWEVER CONFIDENCE IS TOO LOW ON WHEN IT
WILL OCCUR THAT HAVE LEFT POPS JUST UNDER SLIGHT CHANCE. HIGHS
SATURDAY IN THE UPPER 60S TO MID 70S NE TO SW. WARMER SUNDAY AND
MONDAY WITH HIGHS IN THE 70S. LOWS SATURDAY AND SUNDAY NIGHT NEAR 50
NORTH AND MID 50S SOUTH.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
AS OF 750 PM MONDAY...
SCATTERED SHOWERS HAVE DISSIPATED AND MOVED EAST OF ALL TAF SITES
AND WIND GUSTS HAVE FOR THE MOST PART COME TO AN END THIS EVENING.
ALTO STRATUS ENCOMPASSING MOST OF CENTRAL NC IS FORECAST TO ERODE
FROM THE WEST OVERNIGHT...WITH A LIGHT WESTERLY WIND. ANOTHER UPPER
DISTURBANCE ROTATING AROUND THE UPPER LOW MOVING OVER THE GREAT
LAKES WILL CROSS THE CAROLINAS ON TUESDAY. CLOUD COVER WILL
INCREASE AGAIN DURING THE DAY TUESDAY...MOSTLY CU WITH BASES AT OR
ABOVE 5-6K FT. MOST FORECAST MODELS SHOW THE BEST CHANCE OF A FEW
SHOWERS...AND POSSIBLY A BRIEF PERIOD OF MVFR CEILINGS...ACROSS THE
SOUTHERN PIEDMONT AND SANDHILLS DURING THE AFTERNOON. WHILE VFR
CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD...WEST-NORTHWESTERLY
WINDS WILL DEVELOP AFTER SUNRISE...WITH SUSTAINED WINDS OF 10-15KT
AND GUSTS TO 25KT
OUTLOOK...
A PAIR OF CLIPPER-TYPE SYSTEMS ARE FORECAST TO RACE ACROSS THE
MIDWEST TO THE MID ATLANTIC COAST..BRINGING THE CHANCE OF A COUPLE
SUB-VFR CONDITIONS WEDNESDAY NIGHT THROUGH FRIDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...CBL/WSS
SHORT TERM...WSS
LONG TERM...KC
AVIATION...SMITH
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
1035 AM CDT SUN APR 22 2012
.DISCUSSION...
CHALLENGE THIS MORNING IS FOG...LOW CLOUDS AND TEMPERATURES. WILL
FOLLOW LATEST RUC GUIDANCE...WHICH SEEMS TO BE HANDLING CURRENT
SITUATION THE BEST.
LOW STRATUS DECK ALONG AND SOUTHEAST OF A LINE FROM FARGO TO
FOSSTON TO BAUDETTE WILL ERODE FROM NORTHWEST TO SOUTHEAST LATE
THIS MORNING AND AFTERNOON AS WEST-NORTHWEST WIND INCREASES. SOME
THERMAL CUMULUS RE-DEVELOPMENT IS POSSIBLE ALONG THE CLEARING
EDGE WITH CONVECTIVE TEMPERATURES NEAR FORECAST HIGHS. EXPECT MORE
SUN THAN CLOUDS BY MID TO LATE AFTERNOON. ADJUSTED SKY COVER GRIDS
TO REFLECT THESE TRENDS.
CLOUD COVER HAS DAMPENED TEMPERATURE RECOVERY DESPITE WEAK WARM
AIR ADVECTION...SO ADJUSTED HIGHS DOWNWARD A COUPLE DEGREES ACROSS
PORTIONS OF WEST CENTRAL MN. SOME SPOTS MAY STRUGGLE TO BREAK THE
50 DEGREE MARK IF CLOUD COVER IS SLOWER TO MOVE OUT...BUT MOST OF
THE FORECAST AREA WILL TOP OUT IN THE LOWER TO UPPER 50S.
ADDED PATCHY FOG MENTION UNTIL 18 UTC FOR THE NORTHERN VALLEY FROM
BUXTON TO GRAND FORKS TO ROSEAU. VISIBILITY HAS IMPROVED TO 1/2
MILE OR MORE...SO EXPECT FOG TO FULLY DISSIPATE BY THE NOON HOUR.
&&
.AVIATION...
IFR/MVFR STRATUS DECK ALONG AND EAST OF THE VALLEY SHOULD BEGIN TO
LIFT AND SLOWLY DISSIPATE FROM NORTHWEST TO SOUTHEAST LATER THIS
AFTERNOON AS WEST-NORTHWEST WIND INCREASES. MULTIPLE TAF UPDATES
ARE POSSIBLE AS TIMING OF CEILINGS IS DIFFICULT. FOG AT GFK SHOULD
DISSIPATE BY 17 UTC.
&&
.PREV DISCUSSION... /ISSUED 338 AM CDT SUN APR 22 2012/
SHORT TERM...
TEMPERATURES THROUGHOUT THE PERIOD AND WHAT HAPPENS WITH THE
SYSTEM COMING OUT ON TUESDAY WILL BE THE PRIMARY FORECAST PROBLEMS
FOR THE SHORT TERM.
CONDITIONS WILL BE MUCH MORE QUIET TODAY AND TOMORROW AS
NORTHWESTERLY FLOW ALOFT SETS UP BEHIND THE DEPARTING UPPER LOW
AND AHEAD OF THE RIDGE BUILDING OVER THE ROCKIES. SFC HIGH
PRESSURE WILL STRETCH FROM ONTARIO INTO THE PLAINS TODAY. 850MB
TEMPS IN THE EASTERN CWA WILL STILL BE FAIRLY COOL AND THERE WILL
NOT BE A HUGE AMOUNT OF MIXING UNDER THE LIGHT WINDS. ON THE OTHER
HAND...THERE SHOULD BE A FAIR AMOUNT OF SUNSHINE AND SOME WESTERLY
WINDS START MOVING SOME WARMER AIR INTO THE FAR WESTERN CWA THIS
AFTERNOON. DESPITE THE FAIRLY COLD START AROUND FREEZING...THINK
WE SHOULD STILL SEE ENOUGH WARMING TODAY TO GET INTO THE
50S...WITH SOME 60S POSSIBLE IN THE NORTHWEST.
SFC HIGH PRESSURE WILL MOVE SLOWLY OFF TO THE SOUTHEAST
TONIGHT...WITH THE DEVELOPING LOW OVER SASKATCHEWAN SHIFTING WINDS
BACK TO THE SOUTHWEST BY TOMORROW MORNING. LOWS WILL BE A BIT MORE
MILD OVER ALL BUT THE FAR EASTERN COUNTIES WHICH WILL BE HANGING
ONTO LIGHT WINDS A BIT LONGER. THE WARM AIR ADVECTION WILL
CONTINUE INTO MONDAY...WITH WINDS CONTINUING TO PICK UP OUT OF THE
SOUTH TO SOUTHWEST. WITH THE SOUTHWESTERLY WINDS GIVING US SOME
GOOD MIXING AND 850MB TEMPS GETTING BACK INTO THE TEENS C...ALONG
WITH PLENTY OF SUN THINK THAT MOST LOCATIONS WILL SEE THE 60S ON
MONDAY WITH A FEW SPOTS IN THE WEST REACHING THE 70S.
UPPER HEIGHTS WILL START TO COME DOWN A BIT MONDAY NIGHT AND SFC
LOW PRESSURE STARTS TO MOVE INTO THE NORTHERN PLAINS. THE MODELS
HAVE BEEN REALLY STRUGGLING WITH HOW THEY HANDLE THE POSITION OF
THE SFC LOW INTO TUESDAY. THE NAM AND GFS ARE PRETTY FAR NORTH
WITH THE SYSTEM AND HAVE MUCH OF THE CWA IN THE WARM SECTOR OF THE
SFC LOW. THE ECMWF ON THE OTHER HAND...IS FURTHER SOUTH WITH THE
POSITION OF THE LOW AND HAS MUCH OF THE CWA ON THE COOLER EASTERLY
FLOW. CONFIDENCE IS NOT VERY HIGH...SO KEPT POPS IN THE 20-30
PERCENT RANGE WE HAD GOING FOR TUESDAY AND TUESDAY NIGHT. HIGHS IN
THE SOUTHWESTERN COUNTIES COULD GET UP TO OR EVEN ABOVE 80 IF THE
FURTHER NORTH DOMESTIC MODELS VERIFY...WITH THE ECMWF OF COURSE
MUCH COOLER. INCREASED TUESDAY HIGH TEMPS A BIT IN THE WESTERN
COUNTIES...ALTHOUGH DUE TO THE UNCERTAINTY WITH THE POSITION OF
THE LOW DID NOT GET QUITE AS WARM AS THE GFS AND THE NAM.
LONG TERM...
MODELS HAVE BEEN TRENDING WITH MORE DRIER EASTERLY WINDS FOR
FRIDAY NIGHT...SO LOWERED ALLBLEND POPS IN THE EASTERN COUNTIES.
OTHERWISE NO MAJOR CHANGES. TEMPS WILL COOL BACK TOWARDS SEASONAL
AVERAGES OR SLIGHTLY BELOW.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
ROGERS/JR
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
338 AM CDT SUN APR 22 2012
.SHORT TERM...
TEMPERATURES THROUGHOUT THE PERIOD AND WHAT HAPPENS WITH THE
SYSTEM COMING OUT ON TUESDAY WILL BE THE PRIMARY FORECAST PROBLEMS
FOR THE SHORT TERM.
CONDITIONS WILL BE MUCH MORE QUIET TODAY AND TOMORROW AS
NORTHWESTERLY FLOW ALOFT SETS UP BEHIND THE DEPARTING UPPER LOW
AND AHEAD OF THE RIDGE BUILDING OVER THE ROCKIES. SFC HIGH
PRESSURE WILL STRETCH FROM ONTARIO INTO THE PLAINS TODAY. 850MB
TEMPS IN THE EASTERN CWA WILL STILL BE FAIRLY COOL AND THERE WILL
NOT BE A HUGE AMOUNT OF MIXING UNDER THE LIGHT WINDS. ON THE OTHER
HAND...THERE SHOULD BE A FAIR AMOUNT OF SUNSHINE AND SOME WESTERLY
WINDS START MOVING SOME WARMER AIR INTO THE FAR WESTERN CWA THIS
AFTERNOON. DESPITE THE FAIRLY COLD START AROUND FREEZING...THINK
WE SHOULD STILL SEE ENOUGH WARMING TODAY TO GET INTO THE
50S...WITH SOME 60S POSSIBLE IN THE NORTHWEST.
SFC HIGH PRESSURE WILL MOVE SLOWLY OFF TO THE SOUTHEAST
TONIGHT...WITH THE DEVELOPING LOW OVER SASKATCHEWAN SHIFTING WINDS
BACK TO THE SOUTHWEST BY TOMORROW MORNING. LOWS WILL BE A BIT MORE
MILD OVER ALL BUT THE FAR EASTERN COUNTIES WHICH WILL BE HANGING
ONTO LIGHT WINDS A BIT LONGER. THE WARM AIR ADVECTION WILL
CONTINUE INTO MONDAY...WITH WINDS CONTINUING TO PICK UP OUT OF THE
SOUTH TO SOUTHWEST. WITH THE SOUTHWESTERLY WINDS GIVING US SOME
GOOD MIXING AND 850MB TEMPS GETTING BACK INTO THE TEENS C...ALONG
WITH PLENTY OF SUN THINK THAT MOST LOCATIONS WILL SEE THE 60S ON
MONDAY WITH A FEW SPOTS IN THE WEST REACHING THE 70S.
UPPER HEIGHTS WILL START TO COME DOWN A BIT MONDAY NIGHT AND SFC
LOW PRESSURE STARTS TO MOVE INTO THE NORTHERN PLAINS. THE MODELS
HAVE BEEN REALLY STRUGGLING WITH HOW THEY HANDLE THE POSITION OF
THE SFC LOW INTO TUESDAY. THE NAM AND GFS ARE PRETTY FAR NORTH
WITH THE SYSTEM AND HAVE MUCH OF THE CWA IN THE WARM SECTOR OF THE
SFC LOW. THE ECMWF ON THE OTHER HAND...IS FURTHER SOUTH WITH THE
POSITION OF THE LOW AND HAS MUCH OF THE CWA ON THE COOLER EASTERLY
FLOW. CONFIDENCE IS NOT VERY HIGH...SO KEPT POPS IN THE 20-30
PERCENT RANGE WE HAD GOING FOR TUESDAY AND TUESDAY NIGHT. HIGHS IN
THE SOUTHWESTERN COUNTIES COULD GET UP TO OR EVEN ABOVE 80 IF THE
FURTHER NORTH DOMESTIC MODELS VERIFY...WITH THE ECMWF OF COURSE
MUCH COOLER. INCREASED TUESDAY HIGH TEMPS A BIT IN THE WESTERN
COUNTIES...ALTHOUGH DUE TO THE UNCERTAINTY WITH THE POSITION OF
THE LOW DID NOT GET QUITE AS WARM AS THE GFS AND THE NAM.
.LONG TERM...
MODELS HAVE BEEN TRENDING WITH MORE DRIER EASTERLY WINDS FOR
FRIDAY NIGHT...SO LOWERED ALLBLEND POPS IN THE EASTERN COUNTIES.
OTHERWISE NO MAJOR CHANGES. TEMPS WILL COOL BACK TOWARDS SEASONAL
AVERAGES OR SLIGHTLY BELOW.
&&
.AVIATION...
IFR CEILINGS HAVE BEEN HANGING AROUND KBJI AND MOVING BACK INTO
THE KTVF AREA DURING THE LAST FEW HOURS...AND THE HRRR SHOWS SIGNS
THAT THIS WILL CONTINUE. KFAR AT THE EDGE OF THE STRATUS DECK HAS
STAYED MVFR. WILL KEEP THE MVFR/IFR CONDITIONS GOING IN THE
EASTERN TAF SITES THROUGH THE NEXT FEW HOURS...THEN CONDITIONS
SHOULD IMPROVE TO VFR BY MORNING. THE WESTERN TAF SITES WILL STAY
MOSTLY CLEAR...ALTHOUGH WILL HAVE TO WATCH FOR PATCHY FOG
FORMATION. WINDS WILL REMAIN LIGHT FOR MUCH OF THE
DAY...INCREASING OUT OF THE WEST AT AROUND 8 KTS BY AFTERNOON FOR
KDVL.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
JR
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1024 PM EDT MON APR 23 2012
.SYNOPSIS...
DEEP LOW PRESSURE OVER EASTERN NEW YORK WILL MOVE TO NORTH OF LAKE
ONTARIO TONIGHT. THE LOW WILL WEAKEN AS IT MOVES NORTHEAST
TUESDAY AND TUESDAY NIGHT. A WEAK RIDGE OF HIGH PRESSURE WILL
BUILD NORTHEAST ACROSS THE LOCAL AREA TUESDAY AFTERNOON THROUGH
WEDNESDAY. WEAK LOW PRESSURE WILL MOVE EAST ACROSS THE CENTRAL
GREAT LAKES FORCING A COLD FRONT THROUGH THE AREA THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
TOUGH OVERNIGHT FORECAST FOR THE LAKESHORE OF NW PA. ON THE EDGE
ABOUT WHETHER A WARNING OR ADVISORY IS NEEDED. ANOTHER SURGE OF
MOISTURE AND OMEGA IS EXPECTED OVERNIGHT AND THE NORTHWEST WINDS
WILL BECOME MORE WEST NORTHWEST. THIS MAY BRING IN SOME BANDS OF
LAKE EFFECT SNOW INTO THE LAKESHORE COUNTIES. WITH THE WIND AND
THE SNOW BEING WET...THIS COULD CAUSE SOME PROBLEMS. LEFT THE
WARNING GOING...BUT THE BEST CHANCE FOR SIGNIFICANT SNOWFALL WILL
BE FROM INTERSTATE 90 AND SOUTH.
OVER NORTHWEST OHIO SOME CLOUDS AND SOME WIND WILL OCCUR. EVEN
THOUGH THE WINDS HAVE DECREASED AFTER SUNSET...THEY SHOULD
INCREASE AGAIN...JUST ENOUGH TO KEEP THE LOWS FROM GETTING TOO
COLD AND EXTENSIVE FROST. THUS NO HEADLINES FOR THAT AREA.
ELSEWHERE OVER NORTHEAST OHIO...INCREASING CLOUDS. THE
PRECIPITATION MAY NOT GET TOO FAR WEST OF ASHTABULA COUNTY. GOING
WITH THE HRRR MODEL ON THIS...LOWERED THE POPS OVER PARTS OF
NORTHEAST OHIO. MADE SOME ADJUSTMENTS TO THE LOWS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
WARM AIR ADVECTION BEGINS TOMORROW AS THE SURFACE LOW BEGINS TO
LIFT NE. IT SHOULD BECOME WARM ENOUGH FOR ALL RAIN BY MIDDAY
TUESDAY. HAVE SHORTENED THE WARNING BY A FEW HOURS. WESTERN AREAS
SHOULD SEE A FAIR AMOUNT OF SUNSHINE. WEAK HIGH PRESSURE WILL
BEGIN TO BUILD IN LATE TOMORROW AND THIS SHOULD END ANY LINGERING
PRECIP TO THE EAST OF CLEVELAND TOMORROW EVENING. HIGH PRESSURE
WILL REMAIN IN CONTROL WEDNESDAY. MODELS STILL SHOWING ANOTHER
SYSTEM DIVING SE ACROSS THE REGION ON THURSDAY. HAVE ADJUSTED POPS
SLIGHTLY. SUSPECT THAT WE WILL NEED LIKELY POPS FOR A PERIOD OR
TWO. RIGHT NOW IT APPEARS BEST CHANCES FOR PRECIP WILL BE LATE
WEDNESDAY NIGHT AND THURSDAY MORNING. A COLD FRONT WILL MOVE SE
ACROSS THE REGION DURING THE DAY AND WILL TRY TO DRY THINGS OUT
THURSDAY NIGHT. HAVE TRENDED SLIGHTLY COOLER THAN GUIDANCE THE
NEXT COUPLE OF DAYS...ESPECIALLY IN NW PA WHERE THERE WILL BE SOME
SNOW COVER.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
LITTLE CHANGE FOR THE EXTENDED PERIOD. GFS CONTINUES TO MOVE LOW
PRESSURE ACROSS THE OHIO VALLEY/LOWER GREAT LAKES WITH RAIN
DEVELOPING ACROSS AREA ON SATURDAY. ECMWF ON THE OTHER HAND
CONTINUES TO BE FURTHER NORTH WITH THE LOW AND 6-12 HOURS SLOWER
WITH THE RAIN. SINCE LOW CONFIDENCE CONTINUED WITH CHANCE POPS
SATURDAY INTO SUNDAY. KEPT MONDAY DRY AND A LITTLE WARMER AS HIGH
PRESSURE BUILDS OVER THE AREA.
&&
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
LOW PRESSURE SYSTEM OVER UPSTATE NEW YORK WILL SLOWLY TRACK
NORTHWEST INTO TUESDAY. MOISTURE WILL SLOWLY PUSH WESTWARD
TONIGHT...WITH WIDESPREAD PRECIPITATION EXPECTED AT ERI/YNG.
STARTING AS RAIN...PRECIPITATION WILL MIX WITH AND LIKELY CHANGE
OVER TO SNOW BY 4-7Z. ERI WILL EXPERIENCE IFR CONDITIONS OVERNIGHT
WHILE YNG MAY ONLY DROP TO MVFR...UNLESS GETTING CAUGHT UNDER A
MODERATE/HEAVY SNOW SHOWER. SNOW SHOWERS ARE EXPECTED TO DECREASE IN
INTENSITY THROUGH THE MORNING ON TUESDAY. ALTHOUGH SNOW THAT FALLS
OVERNIGHT MAY HAVE A HARD TIME STICKING TO PAVEMENT...ACCUMULATIONS
UP TO 2 INCHES WILL BE POSSIBLE THROUGH 12Z. ELSEWHERE CONDITIONS WILL
REMAIN DRY AND PRIMARILY VFR THROUGH THE TAF CYCLE.
STRONG NORTHWEST WINDS EXPERIENCED TODAY WILL DROP BACK TO NEAR 12
KNOTS WITH GUSTS TO AROUND 20 KNOTS FOR THE OVERNIGHT HOURS. GOOD
MIXING AGAIN ON TUESDAY AFTERNOON WILL RESULT IN WINDS INCREASING TO
NEAR 20 KNOTS AGAIN WITH GUSTS TO 30 KNOTS.
.OUTLOOK...NON VFR LIKELY AGAIN WEDNESDAY NIGHT AND THURSDAY. NON
VFR RETURNING ON SATURDAY.
&&
.MARINE...
LOW PRESSURE OVER EASTERN NEW YORK WILL LINGER OVER NEW YORK STATE
TONIGHT AND THEN GRADUALLY MOVE NORTH INTO ONTARIO AND QUEBEC ON
TUESDAY. THE GALE WARNING HAS BEEN CANCELLED FOR AREAS WEST OF
VERMILLION AS WINDS HAVE DROPPED TO 15 TO 20 KNOTS. SOME INCREASE
IN WINDS IS POSSIBLE ACROSS CENTRAL AND EASTERN LAKE ERIE
OVERNIGHT SO HAVE LEFT THE GALE WARNING IN EFFECT WITH WINDS TO 35
KNOTS FOR THE OVERNIGHT HOURS. A SMALL CRAFT ADVISORY HAS BEEN
ISSUED FOR NEARSHORE WATERS WEST OF VERMILLION AND WILL BE NEEDED
FOR THE REMAINDER OF THE NEARSHORE WATERS ON TUESDAY AS NORTHWEST
WINDS OF 15 TO 25 KNOTS CONTINUE TO GENERATE HIGH WAVES ALONG THE
LAKESHORE. WINDS AND WAVES WILL DECREASE TUESDAY NIGHT AS A RIDGE
OF HIGH PRESSURE BUILDS OVER THE LAKE.
HIGH PRESSURE WILL MOVE TO THE EAST AS LOW PRESSURE AND A COLD
FRONT MOVES ACROSS THE LAKE THURSDAY. NORTHWEST WINDS MAY BE
STRONG ENOUGH TO CAUSE SMALL CRAFT ADVISORY CONDITIONS THURSDAY
NIGHT...BUT THEN WINDS SHOULD DIMINISH AS A RIDGE BUILDS OVER THE
LAKE FRIDAY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...WINTER STORM WARNING UNTIL 11 AM EDT TUESDAY FOR PAZ001>003.
MARINE...GALE WARNING UNTIL 5 AM EDT TUESDAY FOR LEZ061-145>149-165>169.
SMALL CRAFT ADVISORY UNTIL 4 AM EDT WEDNESDAY FOR LEZ142>144.
&&
$$
SYNOPSIS...KUBINA
NEAR TERM...KIELTYKA
SHORT TERM...KUBINA
LONG TERM...DJB
AVIATION...KEC
MARINE...ABE/KEC
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
531 AM EDT SUN APR 22 2012
.SYNOPSIS...
POTENT UPPER LOW SWINGS ACROSS THE AREA THROUGH TONIGHT. DEVELOPING
LOW PRESSURE SYSTEM MOVES NORTH ALONG THE MID ATLANTIC COAST THROUGH
MONDAY. A CLIPPER LIKE SYSTEM AFFECT THE AREA BY MID WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MAIN FORECAST CONCERN OBVIOUSLY WILL BE THE SYSTEM TAKING SHAPE OVER
THE MID-ATLANTIC REGION OVER THE COURSE OF THE NEXT COUPLE OF DAYS
WITH SUBSEQUENT RAIN/SNOW CHANCES FOR THE FORECAST AREA.
NORTHERN STREAM UPPER TROUGH PROGGED TO CLOSE OFF AT H5 BY 18Z
AROUND THE KY/IN/OH AREA. NAM IS COMING INTO BETTER AGREEMENT WITH
THE DEEPER GFS SOLUTION. MEANWHILE THE SOUTHERN STREAM TROUGH
CONTINUES TO FILL AS IT GETS ABSORBED BY STRENGTHENING UPPER LOW OVER
OHIO RIVER VALLEY. SFC LOW MOVING UP THE COAST IN RESPONSE TO
DEVELOPMENT TO ITS WEST WILL BE LOCATED ROUGHLY OVER THE NORTH
CAROLINA COAST BY 18Z...WITH BOTH NAM AND GFS DEPICTING DEEPER LOW
PRESSURE VERSUS PREVIOUS RUNS. VAD PROFILER AT CRW SHOWING DRYING
ABOVE 4KFT OR ABOUT 850MB WHICH RUC SOUNDING SEEMS TO HAVE A DECENT
HANDLE ON. REALLY DON/T BELIEVE THERE WILL BE ANY ONGOING PRECIP
AROUND THE INTERSTATE 79 CORRIDOR AT 15Z BUT CAN/T COMPLETELY RULE
IT OUT SO WILL KEEP SLIGHT CHANCE POPS HERE AT THIS TIME WITH LOW
CHANCE POPS FURTHER SOUTH/EAST ALONG HIGHER TERRAIN...WITH LOW
CHANCE POPS ALONG THE I79 CORRIDOR BY 18Z AS BETTER LLVL MOISTURE
AND WAA WITH GOOD LARGE SCALE FORCING FOR ASCENT BEGIN TO ARRIVE.
LARGE SCALE ASCENT CONTINUES TO INCREASE DURING THE AFTERNOON HOURS
AS H5 UPPER LOW MOVES SE-WARD TOWARDS THE SW PART OF OUR FCST AREA.
990MB ATTENDANT SFC LOW WILL BE LOCATED AROUND THE SOUTHERN DELMARVA
PENINSULA AREA BY 00Z MON. SFC WINDS IN RESPONSE WILL BEGIN TO
SHIFT TO MORE OF A NNW TRAJECTORY WHICH BEGINS TO ENHANCE UPSLOPE
FLOW AGAINST HIGHER TERRAIN. IN ADDITION...GOOD ISENTROPIC LIFT
PARTICULARLY I79 CORRIDOR AND POINTS EAST ON 290K-295K SURFACES WITH
ABUNDANT LLVL MOISTURE UP TO ROUGHLY 500MB WILL ALL MEAN GOOD
CHANCES FOR PRECIP BY 21Z-00Z EASTERN HALF OF FORECAST AREA. ALSO
UNDERCUT LATEST GUIDANCE AND DECREASED MAX TEMPS TODAY BY SEVERAL
DEGREES. WITH ABUNDANT CLOUD COVER...PRECIP RAMPING UP IN THE
AFTERNOON...AND MORNING TEMPS IN THE LOW 40S ACROSS THE
AREA...THINKING THAT TEMPS MAY STRUGGLE TO GET ABOVE 50 AT MOST
LOWLAND LOCATIONS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
COLDER THAN NORMAL TEMPERATURES UNDER NORTHERLY FLOW WILL BRING
FREEZING TEMPERATURES ACROSS THE MOUNTAINS...AND JUST ABOVE
FREEZING LOWLANDS TONIGHT.
A DEVELOPING SFC LOW PRESSURE SYSTEM WILL MOVE NORTH ALONG THE MID
ATLANTIC THROUGH TONIGHT...TO TRANSPORT JUICY GULF STREAM
MOISTURE WEST INTO THE APPALACHIANS. THIS MOISTURE WILL WRAP AROUND
THE MID LATITUDE CYCLONE AS A TROWAL FEATURE EVIDENT IN THE
EQUIVALENT POTENTIAL TEMPERATURE TRAJECTORY FROM THE LOW TO MID
LEVELS INTO THE PORTIONS OF WV TONIGHT AND MONDAY.
AT THE SAME TIME...A POTENT UPPER LEVEL LOW WILL SWING EAST ACROSS
THE OH VALLEY AND WV TONIGHT...AND THEN NORTH INTO THE NORTHEAST
STATES LATE MONDAY. THIS SECOND FEATURE WILL BRING STRONG FORCING
AS SEEN ON H3 TO H4 Q-VECTOR CONVERGENCE. SOME MODELS SUGGEST AXIS
OF 2-D FRONTOGENETICAL FORCING AT H6 TO H7 LAYER.
THESE TWO SYSTEM WILL INTERACT TO PRODUCE COLD TEMPERATURES AND
ASSOCIATED SNOW ACCUMULATIONS MAINLY OVER THE NORTHEAST MOUNTAINS
STARTING TONIGHT...AND CONTINUING INTO EARLY TUESDAY.
FLOW BECOMES NORTHWEST MONDAY...IDEAL FOR UPSLOPE SNOW TO BE
ADDED TO THE SYNOPTIC SNOWS. THEREFORE...INCREASE POPS AND SNOW
AMOUNTS ACROSS THE HIGHER ELEVATIONS...RANGING FROM 5 INCHES LOWER
VALLEYS TO AROUND 10 INCHES AT HIGHEST PEAKS. WARM SOIL
TEMPERATURES WILL PROBABLY MELT THE FIRST SNOWS UPON CONTACT...BUT
EVENTUALLY HEAVY WET SNOW WILL START STICKING ON SURFACES AND
VEGETATION... ESPECIALLY OVER TREE BRANCHES...CAUSING TREE DAMAGES
AND POSSIBLY AFFECTING NEARBY POWER LINES. THEREFORE...A WINTER
STORM WATCH CONTINUES IN EFFECT THROUGH MONDAY MORNING FOR
POCAHONTAS AND RANDOLPH COUNTIES...MAINLY FOR HIGH IMPACT EVENT
FOR SCHOOLS...COMMUTE...AND POWER LINES FLUCTUATIONS OR
INTERRUPTIONS.
IN ADDITION...STRONG GUSTY WINDS COULD EXCEED 40 KNOTS EVIDENT UNDER
280-290K ISENTROPIC CHARTS ON MONDAY. A WIND ADVISORY MAY BE
REQUIRED.
THE UPPER LOW EXITS MONDAY NIGH...BUT THE STRONG NORTHWEST FLOW
COULD KEEP UPSLOPE SNOW FALLING OVER OUR EASTERN MOUNTAINS THROUGH
EARLY TUESDAY. THEREFORE...DELAYED THE ENDING OF POPS OVER THESE
AREAS...WHERE MODELS STILL SHOW DENDRITE GROWTH ZONE AND OMEGA
CROSS HAIL SIGNATURE THROUGH THIS TIME FRAME.
LOWER LOW TEMPS TONIGHT PER STRONGER H850 FLOW...ALTHOUGH MODELS
SHOW CONSISTENCY ON MINUS 4C AT THIS LEVEL FROM PREVIOUS RUNS. AS
THE AFOREMENTIONED SYNOPTIC SYSTEMS LIFT NORTH AWAY FROM THE
AREA...MODELS SUGGEST A 2 DEGREE WARM ADVECTION AT H850. WITH THE
EXPECTED SNOW COVER AND HIGH ELEVATIONS EFFECTS...CODED A SFC
TEMPERATURE GRADIENT RANGING FROM THE LOWER 50S PORTIONS OF SE OH
AND NORTHEAST KY...TO THE LOWER 30S NORTHEAST HIGHEST PEAKS.
ACCUMULATION COULD GREATLY CHANGE DEPENDING ON THE SURFACE LOW
TRACK...WITH HIGHER AMOUNTS POSSIBLE IF THE LOW TRACKS FARTHER
WEST.
WESTERLY FLOW WILL BRING WARM ADVECTION AT H850 TO KEEP ANY PCPN AS
LIQUID FROM OTHER DISTURBANCES APPROACHING ON TUESDAY. MINOR
TEMPERATURE CHANGES NOTED THROUGH THIS TIME PERIODS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
WARM ADVECTION PRECIPITATION AHEAD OF CLIPPER SYSTEM RACES INTO THE
AREA TUE NT. SURFACE LOW CENTER DOES NOT CROSS UNTIL WED NT...AND
IT WILL TAKE UNTIL LATE THU OR THU NT FOR THE PRECIPITATION TO EXIT
THE AREA TO THE SE. MODELS ARE IN BETTER AGREEMENT WITH THE
SCENARIO ALTHOUGH ECMWF CONTINUES TO SHOW A MORE SRN TRACK THAN THE
GFS WITH DEEPER LONG WAVE TROF ALONG E COAST. HPC SOLN IS CLOSEST
TO MORE NORTHERN SOLN AND SO ARE THE GRIDS.
BLENDED IN HPC FOR THE MOST PART FOR TEMPERATURES ALTHOUGH TRENDED
MORE TOWARD A BLEND ALL LATE IN THE PERIOD. HAVE SLIGHTLY HIGHER
LOWS IN THE WARM ADVECTION AHEAD OF THE CLIPPER TUE NT...AND THEN
HAVE TEMPERATURES A BIT LOWER IN THE PRECIPITATION ASSOCIATED WITH
THE CLIPPER AS WELL AS IN THE COOLER AIR BEHIND IT.
&&
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
06Z SUNDAY THROUGH 06Z MONDAY... SOLID VLIFR-IFR FLIGHT CONDITIONS
WILL PREVAIL OVERNIGHT...WITH INTERMITTENT MVFR CIGS. IMPROVEMENT
TO MVFR OR LOW VFR AFTER 15Z SUNDAY ACROSS MUCH OF THE LOWLANDS...WITH
MVFR/IFR CONTINUING TO LINGER ACROSS THE HIGHER TERRAIN. A RETURN
TO IFR CONDITIONS CAN BE EXPECTED BY 06Z MONDAY WITH PERHAPS LOW
MVFR CIGS HANGING ON AT WESTERN SITES SUCH AS HTS AND PKB.
A STRONG LOW PRESSURE SYSTEM WILL MOVE NORTH ALONG THE COAST ON
SUNDAY. THIS WILL SPREAD PRECIPITATION BACK INTO THE AREA...PARTICULARLY
ACROSS NORTHERN/CENTRAL WV AFTER 18-21Z. PRECIPITATION IS EXPECTED
TO REMAIN IN THE FORM OF RAIN BEFORE 21Z SUN...BUT WILL BEGIN TO
TRANSITION TO SNOW ACROSS THE NORTHERN MOUNTAINS INCLUDING EKN
BTWN 21Z-00Z...WITH SNOW EXPECTED AT EKN BY 00Z MON AND
DRASTICALLY REDUCING VIS AT THIS POINT. IN ADDITION...GUSTY NORTH TO
NORTHEAST WINDS WILL DEVELOP AFTER 15Z SUNDAY...WITH GUSTS OF UP
TO 22KTS ACROSS THE LOWLANDS...AND UP TO 30 KTS ACROSS THE HIGHER
TERRAIN.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z MONDAY...
FORECAST CONFIDENCE...MEDIUM.
ALTERNATE SCENARIOS: IMPROVEMENT IN CEILINGS MAY VARY BY A COUPLE
OF HOURS ON SUNDAY. EXPECTED IFR CEILINGS 00Z-15Z WILL LINGER
NEAR THRESHOLD OF MVFR LEAVING SMALL MARGIN FOR ERROR.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SUN 04/22/12
UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19
EDT 1HRLY 04 05 06 07 08 09 10 11 12 13 14 15
CRW CONSISTENCY M M M M M M M M L H H H
HTS CONSISTENCY H H H M M M M L L H H H
BKW CONSISTENCY M M M M M M L L M L L L
EKN CONSISTENCY L M M M M M M M L L L L
PKB CONSISTENCY M M M M M H L M L L L L
CKB CONSISTENCY M M H H H M L H L H H H
AFTER 12Z MONDAY...
IFR EXPECTED IN MOUNTAIN SNOW SUNDAY NIGHT THROUGH TUESDAY MORNING.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...WINTER STORM WATCH FROM LATE TONIGHT THROUGH MONDAY EVENING
FOR WVZ046-047.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/50
NEAR TERM...50
SHORT TERM...ARJ
LONG TERM...TRM
AVIATION...50
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
457 AM EDT SUN APR 22 2012
.SYNOPSIS...
POTENT UPPER LOW SWINGS ACROSS THE AREA THROUGH TONIGHT. DEVELOPING
LOW PRESSURE SYSTEM MOVES NORTH ALONG THE MID ATLANTIC COAST THROUGH
MONDAY. A CLIPPER LIKE SYSTEM AFFECT THE AREA BY MID WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MAIN FORECAST CONCERN OBVIOUSLY WILL BE THE SYSTEM TAKING SHAPE OVER
THE MID-ATLANTIC REGION OVER THE COURSE OF THE NEXT COUPLE OF DAYS
WITH SUBSEQUENT RAIN/SNOW CHANCES FOR THE FORECAST AREA.
NORTHERN STREAM UPPER TROUGH PROGGED TO CLOSE OFF AT H5 BY 18Z
AROUND THE KY/IN/OH AREA. NAM IS COMING INTO BETTER AGREEMENT WITH
THE DEEPER GFS SOLUTION. MEANWHILE THE SOUTHERN STREAM TROUGH
CONTINUES TO FILL AS IT GETS ABSORBED BY STRENGTHENING UPPER LOW OVER
OHIO RIVER VALLEY. SFC LOW MOVING UP THE COAST IN RESPONSE TO
DEVELOPMENT TO ITS WEST WILL BE LOCATED ROUGHLY OVER THE NORTH
CAROLINA COAST BY 18Z...WITH BOTH NAM AND GFS DEPICTING DEEPER LOW
PRESSURE VERSUS PREVIOUS RUNS. VAD PROFILER AT CRW SHOWING DRYING
ABOVE 4KFT OR ABOUT 850MB WHICH RUC SOUNDING SEEMS TO HAVE A DECENT
HANDLE ON. REALLY DON/T BELIEVE THERE WILL BE ANY ONGOING PRECIP
AROUND THE INTERSTATE 79 CORRIDOR AT 15Z BUT CAN/T COMPLETELY RULE
IT OUT SO WILL KEEP SLIGHT CHANCE POPS HERE AT THIS TIME WITH LOW
CHANCE POPS FURTHER SOUTH/EAST ALONG HIGHER TERRAIN...WITH LOW
CHANCE POPS ALONG THE I79 CORRIDOR BY 18Z AS BETTER LLVL MOISTURE
AND WAA WITH GOOD LARGE SCALE FORCING FOR ASCENT BEGIN TO ARRIVE.
LARGE SCALE ASCENT CONTINUES TO INCREASE DURING THE AFTERNOON HOURS
AS H5 UPPER LOW MOVES SE-WARD TOWARDS THE SW PART OF OUR FCST AREA.
990MB ATTENDANT SFC LOW WILL BE LOCATED AROUND THE SOUTHERN DELMARVA
PENINSULA AREA BY 00Z MON. SFC WINDS IN RESPONSE WILL BEGIN TO
SHIFT TO MORE OF A NNW TRAJECTORY WHICH BEGINS TO ENHANCE UPSLOPE
FLOW AGAINST HIGHER TERRAIN. IN ADDITION...GOOD ISENTROPIC LIFT
PARTICULARLY I79 CORRIDOR AND POINTS EAST ON 290K-295K SURFACES WITH
ABUNDANT LLVL MOISTURE UP TO ROUGHLY 500MB WILL ALL MEAN GOOD
CHANCES FOR PRECIP BY 21Z-00Z EASTERN HALF OF FORECAST AREA. ALSO
UNDERCUT LATEST GUIDANCE AND DECREASED MAX TEMPS TODAY BY SEVERAL
DEGREES. WITH ABUNDANT CLOUD COVER...PRECIP RAMPING UP IN THE
AFTERNOON...AND MORNING TEMPS IN THE LOW 40S ACROSS THE
AREA...THINKING THAT TEMPS MAY STRUGGLE TO GET ABOVE 50 AT MOST
LOWLAND LOCATIONS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
COLDER THAN NORMAL TEMPERATURES UNDER NORTHERLY FLOW WILL BRING
FREEZING TEMPERATURES ACROSS THE MOUNTAINS...AND JUST ABOVE
FREEZING LOWLANDS TONIGHT.
A DEVELOPING SFC LOW PRESSURE SYSTEM WILL MOVE NORTH ALONG THE MID
ATLANTIC THROUGH TONIGHT...TO TRANSPORT JUICY GULF STREAM
MOISTURE WEST INTO THE APPALACHIANS. THIS MOISTURE WILL WRAP AROUND
THE MID LATITUDE CYCLONE AS A TROWAL FEATURE EVIDENT IN THE
EQUIVALENT POTENTIAL TEMPERATURE TRAJECTORY FROM THE LOW TO MID
LEVELS INTO THE PORTIONS OF WV TONIGHT AND MONDAY.
AT THE SAME TIME...A POTENT UPPER LEVEL LOW WILL SWING EAST ACROSS
THE OH VALLEY AND WV TONIGHT...AND THEN NORTH INTO THE NORTHEAST
STATES LATE MONDAY. THIS SECOND FEATURE WILL BRING STRONG FORCING
AS SEEN ON H3 TO H4 Q-VECTOR CONVERGENCE. SOME MODELS SUGGEST AXIS
OF 2-D FRONTOGENETICAL FORCING AT H6 TO H7 LAYER.
THESE TWO SYSTEM WILL INTERACT TO PRODUCE COLD TEMPERATURES AND
ASSOCIATED SNOW ACCUMULATIONS MAINLY OVER THE NORTHEAST MOUNTAINS
STARTING TONIGHT...AND CONTINUING INTO EARLY TUESDAY.
FLOW BECOMES NORTHWEST MONDAY...IDEAL FOR UPSLOPE SNOW TO BE
ADDED TO THE SYNOPTIC SNOWS. THEREFORE...INCREASE POPS AND SNOW
AMOUNTS ACROSS THE HIGHER ELEVATIONS...RANGING FROM 5 INCHES LOWER
VALLEYS TO AROUND 10 INCHES AT HIGHEST PEAKS. WARM SOIL
TEMPERATURES WILL PROBABLY MELT THE FIRST SNOWS UPON CONTACT...BUT
EVENTUALLY HEAVY WET SNOW WILL START STICKING ON SURFACES AND
VEGETATION... ESPECIALLY OVER TREE BRANCHES...CAUSING TREE DAMAGES
AND POSSIBLY AFFECTING NEARBY POWER LINES. THEREFORE...A WINTER
STORM WATCH CONTINUES IN EFFECT THROUGH MONDAY MORNING FOR
POCAHONTAS AND RANDOLPH COUNTIES...MAINLY FOR HIGH IMPACT EVENT
FOR SCHOOLS...COMMUTE...AND POWER LINES FLUCTUATIONS OR
INTERRUPTIONS.
THE UPPER LOW EXITS MONDAY NIGH...BUT THE STRONG NORTHWEST FLOW
COULD KEEP UPSLOPE SNOW FALLING OVER OUR EASTERN MOUNTAINS THROUGH
EARLY TUESDAY. THEREFORE...DELAYED THE ENDING OF POPS OVER THESE
AREAS...WHERE MODELS STILL SHOW DENDRITE GROWTH ZONE AND OMEGA
CROSS HAIL SIGNATURE THROUGH THIS TIME FRAME.
LOWER LOW TEMPS TONIGHT PER STRONGER H850 FLOW...ALTHOUGH MODELS
SHOW CONSISTENCY ON MINUS 4C AT THIS LEVEL FROM PREVIOUS RUNS. AS
THE AFOREMENTIONED SYNOPTIC SYSTEMS LIFT NORTH AWAY FROM THE
AREA...MODELS SUGGEST A 2 DEGREE WARM ADVECTION AT H850. WITH THE
EXPECTED SNOW COVER AND HIGH ELEVATIONS EFFECTS...CODED A SFC
TEMPERATURE GRADIENT RANGING FROM THE LOWER 50S PORTIONS OF SE OH
AND NORTHEAST KY...TO THE LOWER 30S NORTHEAST HIGHEST PEAKS.
ACCUMULATION COULD GREATLY CHANGE DEPENDING ON THE SURFACE LOW
TRACK...WITH HIGHER AMOUNTS POSSIBLE IF THE LOW TRACKS FARTHER
WEST.
WESTERLY FLOW WILL BRING WARM ADVECTION AT H850 TO KEEP ANY PCPN AS
LIQUID FROM OTHER DISTURBANCES APPROACHING ON TUESDAY NIGHT
THROUGH WEDNESDAY. MINOR TEMPERATURE CHANGES NOTED THROUGH THIS
TIME PERIODS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
WARM ADVECTION PRECIPITATION AHEAD OF CLIPPER SYSTEM RACES INTO THE
AREA TUE NT. SURFACE LOW CENTER DOES NOT CROSS UNTIL WED NT...AND
IT WILL TAKE UNTIL LATE THU OR THU NT FOR THE PRECIPITATION TO EXIT
THE AREA TO THE SE. MODELS ARE IN BETTER AGREEMENT WITH THE
SCENARIO ALTHOUGH ECMWF CONTINUES TO SHOW A MORE SRN TRACK THAN THE
GFS WITH DEEPER LONG WAVE TROF ALONG E COAST. HPC SOLN IS CLOSEST
TO MORE NORTHERN SOLN AND SO ARE THE GRIDS.
BLENDED IN HPC FOR THE MOST PART FOR TEMPERATURES ALTHOUGH TRENDED
MORE TOWARD A BLEND ALL LATE IN THE PERIOD. HAVE SLIGHTLY HIGHER
LOWS IN THE WARM ADVECTION AHEAD OF THE CLIPPER TUE NT...AND THEN
HAVE TEMPERATURES A BIT LOWER IN THE PRECIPITATION ASSOCIATED WITH
THE CLIPPER AS WELL AS IN THE COOLER AIR BEHIND IT.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
06Z SUNDAY THROUGH 06Z MONDAY... SOLID VLIFR-IFR FLIGHT CONDITIONS
WILL PREVAIL OVERNIGHT...WITH INTERMITTENT MVFR CIGS. IMPROVEMENT
TO MVFR OR LOW VFR AFTER 15Z SUNDAY ACROSS MUCH OF THE LOWLANDS...WITH
MVFR/IFR CONTINUING TO LINGER ACROSS THE HIGHER TERRAIN. A RETURN
TO IFR CONDITIONS CAN BE EXPECTED BY 06Z MONDAY WITH PERHAPS LOW
MVFR CIGS HANGING ON AT WESTERN SITES SUCH AS HTS AND PKB.
A STRONG LOW PRESSURE SYSTEM WILL MOVE NORTH ALONG THE COAST ON
SUNDAY. THIS WILL SPREAD PRECIPITATION BACK INTO THE AREA...PARTICULARLY
ACROSS NORTHERN/CENTRAL WV AFTER 18-21Z. PRECIPITATION IS EXPECTED
TO REMAIN IN THE FORM OF RAIN BEFORE 21Z SUN...BUT WILL BEGIN TO
TRANSITION TO SNOW ACROSS THE NORTHERN MOUNTAINS INCLUDING EKN
BTWN 21Z-00Z...WITH SNOW EXPECTED AT EKN BY 00Z MON AND
DRASTICALLY REDUCING VIS AT THIS POINT. IN ADDITION...GUSTY NORTH TO
NORTHEAST WINDS WILL DEVELOP AFTER 15Z SUNDAY...WITH GUSTS OF UP
TO 22KTS ACROSS THE LOWLANDS...AND UP TO 30 KTS ACROSS THE HIGHER
TERRAIN.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z MONDAY...
FORECAST CONFIDENCE...MEDIUM.
ALTERNATE SCENARIOS: IMPROVEMENT IN CEILINGS MAY VARY BY A COUPLE
OF HOURS ON SUNDAY. EXPECTED IFR CEILINGS 00Z-15Z WILL LINGER
NEAR THRESHOLD OF MVFR LEAVING SMALL MARGIN FOR ERROR.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SUN 04/22/12
UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19
EDT 1HRLY 04 05 06 07 08 09 10 11 12 13 14 15
CRW CONSISTENCY M M M M M M M M L H H H
HTS CONSISTENCY H H H M M M M L L H H H
BKW CONSISTENCY M M M M M M L L M L L L
EKN CONSISTENCY L M M M M M M M L L L L
PKB CONSISTENCY M M M M M H L M L L L L
CKB CONSISTENCY M M H H H M L H L H H H
AFTER 06Z MONDAY...
IFR EXPECTED IN MOUNTAIN SNOW SUNDAY NIGHT THROUGH TUESDAY MORNING.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...WINTER STORM WATCH FROM LATE TONIGHT THROUGH MONDAY EVENING
FOR WVZ046-047.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/50
NEAR TERM...50
SHORT TERM...ARJ
LONG TERM...TRM
AVIATION...50
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
604 PM CDT SUN APR 22 2012
.UPDATE...
UPPER DISTURBANCE UPSTREAM CONTINUES TO PRODUCE A FEW SHOWERS
ACROSS SOUTHERN KY. LATEST GFS AND RUC SOLUTIONS CONTINUE TO
ENDORSE THE CONTINUATION OF A FEW LIGHT SHOWERS FOR THE MID STATE
INTO EARLY EVENING. OTW...REMAINDER OF FCST APPEARS TO BE IN GOOD
SHAPE WITH A SLIGHT DECREASE IN WIND SPEEDS...DECREASING CLOUD
COVER AND FALLING TEMPS WITH PATCHY LATE NIGHT FROST.
FOR THE UPDATE...WILL INCLUDE ISOL POPS FOR SHOWERS THROUGH EARLY
EVENING. THIS WILL THEREBY CALL FOR AN ADDITIONAL UPDATE BY 9 PM
OR SO.
UPDATE OUT SHORTLY.
&&
.PREV DISCUSSION... /ISSUED 242 PM CDT SUN APR 22 2012/
DISCUSSION...CLOUDS WERE INCREASING ACROSS MID TN THIS AFTERNOON
AND A FEW SHOWERS WERE DEVELOPING OVER OUR WESTERN COUNTIES. MORE
SHOWERS WERE INDICATED OVER WEST KY AND SE MO...MOVING TOWARD WEST
SECTIONS OF THE MID STATE. TEMPERATURES WERE COOL...IN THE 50S TO
LOWER 60S...WITH A NW BREEZE TO 25 MPH AT TIMES.
A COUPLE OF MID/UPPER LOWS WERE OBSERVED...ONE MOVING NE FROM FL
AND THE OTHER DROPPING ACROSS THE OH VALLEY. THESE SYSTEMS WILL
BE COMING TOGETHER AS A NOR`EASTER FORMS AND BRINGS SIGNIFICANT WX
TO THE EAST COAST. THE MAIN FEATURE OF INTEREST FOR MID TN IS THE
UPPER LOW DROPPING ACROSS THE OH VALLEY THIS AFTERNOON. STEEP LAPSE
RATES WERE DEVELOPING...CAUSING INCREASING CLOUDS AND A FEW SHOWERS. AS
ADDITIONAL SHORTWAVE ENERGY SPINS AROUND THIS LOW...WE WILL
CONTINUE TO SEE A FEW SHOWERS...PERHAPS EVEN SOME
THUNDER...DEVELOP THROUGH LATE AFTERNOON. MODELS CONTINUE TO FOCUS
MOST ACTIVITY WEST OF I 65. THIS ACTIVITY IS LARGELY HEAT
DRIVEN...SO CONVECTION WILL DISSIPATE QUICKLY WITH SUNSET. WE WILL
POST LOW POPS FOR TONIGHT...BUT THAT APPLIES AFTER 00Z. ZONES WILL
INDICATE A LATE AFTERNOON PERIOD FOR MENTION OF POSSIBLE SHOWERS
OR THUNDERSTORMS (20-30 POPS) VALID FROM NOW UNTIL 00Z WHEN
ACTIVITY IS EXPECTED TO FIZZLE. LATER TONIGHT...CLEARING SKIES AND
CHILLY AIR WILL ALLOW TEMPERATURES TO FALL INTO THE 30S. WE WILL
MENTION PATCHY FROST IN THE FORECAST...BUT THIS REALLY ONLY
APPLIES OT THE MOST SHELTERED LOCATIONS. A PERSISTENT WIND THROUGH
THE NIGHT WILL NOT BE CONDUCIVE FOR FROST IN MOST AREAS.
ON MONDAY...SKIES WILL VARY FROM MOSTLY TO PARTLY SUNNY. IT WILL
BE ANOTHER CHILLY AND BREEZY DAY THANKS TO NW FLOW AND A TIGHT
PRESSURE GRADIENT ASSOCIATED WITH DEEP EAST COAST LOW PRESSURE
SYSTEM. TEMPS WILL BE AROUND 10 DEGREES BELOW NORMAL WITH NW WIND
GUSTS TO 30 MPH AT TIMES.
MONDAY NIGHT WILL BE CLEAR TO PARTLY CLOUDY AND CHILLY AGAIN. MANY
AREAS WILL DROP INTO THE 30S. THERE IS A GREATER RISK FOR FROST
MONDAY NIGHT...ALTHOUGH STILL NOT IDEAL FOR WIDESPREAD FROST.
FOR TUESDAY AND TUESDAY NIGHT...DIRTY NW FLOW WILL KEEP CONDITIONS
COOL WITH INTERVALS OF CLOUDS. A SMALL CHANCE FOR SHOWERS CANNOT
BE RULED OUT...BUT NOTHING SPECIFIC TO BASE POPS ON AT THIS TIME.
RAIN CHANCES WILL RAMP UP LATE WEDNESDAY INTO THURSDAY AS A FRONT
APPROACHES. MODELS HAVE BEEN INCONSISTENT ON THE EXACT PLACEMENT
OF THIS FRONT AS IT SETTLES ACROSS THE TN VALLEY AREA...STALLS...THEN
EVENTUALLY RETURNS NORTH LATE WEEK. THE EXACT LOCATION OF THE FRONT
WILL GREATLY INFLUENCE ALL FORECAST ELEMENTS. BECAUSE OF THE
UNCERTAINTY...WE WILL BROAD BRUSH MID TO LATE WEEK WITH CHANCES
FOR SHOWERS AND STORMS EACH DAY AND A MODEL BLEND FOR
TEMPERATURES.
13
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
150 AM EDT SUN APR 22 2012
.SYNOPSIS...
A DEEP AREA OF LOW PRESSURE ALOFT AND AT THE SURFACE WILL MOVE
FROM THE SOUTHEAST U.S. NORTHWARD ALONG THE EAST COAST THROUGH
MONDAY. A VARIETY OF INCLEMENT WEATHER WILL ACCOMPANY THIS SYSTEM
DURING THE NEXT SEVERAL DAYS...CONSISTING OF SHOWERS AND STORMS
ACROSS THE PIEDMONT TONIGHT...THEN WIDESPREAD RAIN SUNDAY.
CONSIDERABLY COLDER AIR WILL WRAP AROUND THE BACK SIDE OF THE
SYSTEM...WITH ACCUMULATING SNOW POSSIBLE BY EARLY MONDAY ACROSS
THE CENTRAL AND NORTHERN APPALACHIANS.
&&
.NEAR TERM /THROUGH SUNDAY/...
AS OF 815 PM EDT SATURDAY...
NOT A LOT OF CHANGE TO THE GOING FORECAST TONIGHT WITH THE SURFACE
COLD FRONT NOW ACROSS THE FAR SE WHERE THE PRE-FRONTAL BAND OF
CONVECTION HAS BASICALLY COME TO A HALT. LATEST HRRR AND LOCAL WRF
TEND TO DEVELOP THIS AXIS OF SHRA/TSRA A LITTLE MORE TO THE SE
THRU MIDNIGHT BEFORE BACKING STARTS OVERRUNNING THE BOUNDARY
OVERNIGHT AS THE GULF LOW STARTS TO WORK NE UP THE COAST BY
MORNING. ALTHO CONVECTION REMAINS RATHER SHALLOW OVER THE
SE...WILL NEED TO WATCH FOR TRAINING OF CELLS PENDING JUST HOW
MUCH THE COVERAGE DECREASES WITH LOSS OF HEATING AS LATEST SPC
MESO ANALYSIS SHOWS BEST CAPE NOW JUST SE OF THE CWA. THUS DID ADD
A COUPLE HOURS OF HVY RAIN MENTION...MAINLY ACROSS SOUTHSIDE VA/NW
NC PIEDMONT INTO LATE THIS EVENING...WITH POPS LOWERING TO LIKELYS
BEFORE RATCHETING BACK UP TO CATEGORICAL AS PRECIP STARTS TO HEAD
BACK TO THE NNW AFTER MIDNIGHT. MAINLY RUNNING WITH CHANCE TO
SLIGHT POPS ELSW WITH A FEW SHRA/ISOLD -TSRA BANDS LEFTOVER ALONG
THE SRN BLUE RIDGE PER A WEAK SURFACE WAVE NEAR CLT IN BETWEEN
THE SFC AND 85H FRONT STILL BACK IN SE WVA. APPEARS STEADIER RAIN
WONT REDEVELOP OUTSIDE OF THE SE UNTIL TOWARD DAYBREAK WHEN DEEPER
EASTERLY FLOW ESTABLISHES WITH THE HEAVIEST CLOSER TO THE RESIDUAL
FRONT AND PERHAPS IN A DEFORMATION ZONE FARTHER WEST ACROSS THE
MOUNTAINS. OTRW GOING LOW TEMPS LOOK ABOUT ON TRACK AS LOW LEVEL
COOL ADVECTION OOZES IN ALLOWING MOST LOCATIONS EXCEPT THE FAR SE
TO FALL INTO THE 40S BY MORNING.
PREVIOUS DISCUSSION AS OF 350 PM EDT SATURDAY...
SCATTERED SHOWERS AND STORMS WILL CONTINUE MOVING EAST THROUGH
THIS AFTERNOON...EVENTUALLY TO BE REPLACED BY A MORE STEADY
STRATIFORM BEHIND THE COLD FRONT WHICH HAS SLOWED DOWN
CONSIDERABLY OVER THE NEW RIVER AND ROANOKE VALLEYS. WINDS MAY
GUST TO 30 MPH WITH ANY THUNDERSTORMS. BEST CHANCE FOR STRONG
STORMS REMAINS IN THE LYH/DAN/SIF CORRIDOR AS THOSE SPOTS GOT
CLOSE TO 80F TODAY BEFORE CLOUDS ARRIVED WITH MID 50S DEWPOINTS.
SOME OF THE CLUSTERS NOW MERGING IN NW NC MAY STRENGTHEN AS THEY
TOUCH THE 1K J/KG CAPE AND 35 M/S 0-6 KM SHEAR WHICH RESIDES EAST
OF THE BLUE RIDGE. BIGGEST THREAT WILL BE GUSTY WINDS...ALTHOUGH
SOME PEA SIZED HAIL WAS REPORTED WITH STORMS OVER HILLSVILLE A FEW
HOURS AGO. INSTABILITY WANES THIS EVENING AS FRONT SLIDES
EAST...WITH A BREAK IN THE PRECIP. BUT STRONG SURFACE LOW WITH
STOUT UPPER WAVE MOVES UP THE COAST SPREADING STRATIFORM RAIN
ACROSS THE ENTIRE CWA BY 12Z/8A SUNDAY. RAIN MAY BE HVY AT TIMES
LYH/DAN AND POINTS EAST WITH POSSIBLY AN INCH OF RAIN DURING THE
DAYTIME HOURS SUNDAY. PUT HVY RAIN IN THE WX GRIDS. ALSO TIGHT
PRESSURE GRADIENT COULD CAUSE LYH TO GUST TO 30 MPH FROM THE NE
MIDDAY. INC POPS ACROSS THE CWA. MORNING TEMPS WILL LIKELY BE
HIGHS FOR THE DAY...SO WENT WITH TEMPS SLOWLY FALLING DURING THE
DAY WITH IMPRESSIVE DEEP N TO NE FLOW AND PRECIP AL DAY. TEMPS
WILL PROBABLY BE IN THE MID TO UPPER 40S TOMORROW AFTERNOON AFTER
MORNING MAX T...ALTHOUGH WARMER MARITIME AIR MAY KEEP SOUTHSIDE IN
THE 50S DURING THE DAY. NW WINDS DEVELOPING LATE AND DOWNSLOPING
COULD ALSO ALLOW NW NC TO GUST TO 30 MPH LATE DAY. AN INCH OR TWO
OF RAIN MAY FALL TOTAL TONIGHT THROUGH SUN NIGHT IN THE PIEDMONT
AND SOUTHSIDE.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
AS OF 315 PM EDT SATURDAY...
GOING TO SEE A TRANSITION TO COLDER AND WINDY WEATHER THIS PERIOD.
MODELS SHOW ENOUGH AGREEMENT IN TRACK OF THE SFC/UPPER LOW THAT
SUNDAY EVENING SHOWERS WILL BE FALLING ACROSS A GOOD DEAL OF THE
AREA...BUT STARTING TO DRY OUT IN THE SOUTHWEST. AS THE UPPER LOW
DEEPENS OVER WRN VIRGINIA LATE SUNDAY NIGHT...8H TEMPS DROP TO -2 IN
THE MTNS WHERE RAIN SHOWERS WILL CHANGE TO SNOW SHOWERS. ATTM...MADE
SOME UPWARD ADJUSTMENTS ON ACCUMULATION...BUT EXPECT IT TO STAY
BELOW ANY ADVISORY LEVELS...AS THE GROUND WILL BE WARM...AND SPEED
OF SYSTEM MAY LIMIT PERIOD OF STRONG LIFT/COLDER TEMPS STAYING
OVERHEAD. ATTM...WILL SEE AN INCH OR MORE ACROSS THE HIGHER
ELEVATIONS (ABOVE 4000 FEET) LATE SUNDAY NIGHT-MONDAY MORNING. THIS
INCLUDES MOUNT ROGERS...BURKES GARDEN AREA...AND THE HIGHLANDS OF
BATH...WEST INTO GREENBRIER COUNTY. GIVEN AMOUNT OF QPF...WRN
GREENBRIER STANDS THE BEST SHOT OF SEEING SEVERAL INCHES OF WET
SNOW.
THIS SYSTEM SWINGS INLAND SOME MONDAY AND DEEPENS TO A 986 LOW
ACROSS NEW YORK. MODELS SHOW ENOUGH OF A TIGHT GRADIENT AND 8H WINDS
OF 45-50 KNOTS THAT WILL BE BUMPING WIND GUSTS UP TO 30+ KNOTS.
WOULD NOT BE SURPRISED TO SEE A WIND ADVISORY...MAYBE A HIGH WIND
WARNING FOR A PERIOD OF TIME MONDAY....BUT WILL WAIT FOR MORE
CONSISTENCY IN MODELS AND ANOTHER RUN OR TWO BEFORE ISSUING
HEADLINES IF NEEDED.
THE SNOW THREAT/WIND THREAT IS MENTIONED IN THE HAZARDOUS WEATHER
OUTLOOK.
THE SHOWERY CONDITIONS WILL BE STARTING TO WIND DOWN DURING THE AFTN
MONDAY AS MOISTURE STARTS TO BECOME MORE LIMITED. ANOTHER VORT
TAKING A SEWD TURN AROUND THE UPPER LOW MONDAY NIGHT WILL KEEP A FEW
RAIN/SNOW SHOWERS FALLING INTO THE MTNS OF SE WV. TEMPS SLIP INTO
THE UPPER 20S MON NIGHT IN THE MTNS TO THE MID TO UPPER 30S OUT
EAST. WINDS WILL FROST FROM FORMING...BUT DEFINITELY COULD SEE A
FREEZE IN THE MOUNTAINS.
TUESDAY...THERE STILL EXISTS A GRADIENT BETWEEN THE DEPARTING LOW
INTO CANADA AND HIGH PRESSURE IN THE GULF OF MEXICO. ANOTHER
SHORTWAVE MOVES ACROSS TUESDAY AFTN AND COULD SEE WEST WINDS GUSTING
TO 25 - 35 MPH AT TIMES.
AS FOR TEMPS...MADE IT COOLER IN THE MOUNTAINS MONDAY WITH
40S...SOME UPPER 30S HIGHER ELEVATIONS TO 50S EAST PER DOWNSLOPE.
TUESDAY WILL BE MILDER IN THE EAST WITH 60S AND FLOW TURNING MORE
WEST...WHILE THE MOUNTAINS STAY IN THE 50S.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 130 PM EDT SATURDAY...
THE ECMWF AND GFS DEPICT A CLIPPER TRACKING SOUTHEASTWARD FROM THE
UPPER MIDWEST TO THE OHIO RIVER VALLEY FOR TUESDAY NIGHT INTO
WEDNESDAY. SOME SHOWERS MAY SPREAD AHEAD OF IT AND REACH THE WESTERN
PART OF THE CWA BY WEDNESDAY MORNING...AND THE PIEDMONT LATER IN
THE DAY. THE CLIPPER WILL PASS OVER THE CWA DURING WEDNESDAY NIGHT
INTO THURSDAY...BUT THE MODELS DIVERGE SIGNIFICANTLY WITH THE
DETAILS. THE ECMWF SHOWS EASTERLY SFC WINDS AND HIGHER QPF FROM
THE CLIPPER...WHILE THE GFS SHOWS WESTERLY SFC WINDS AND LOWER QPF.
IF THE ECMWF VERIFIES...A COLD WEDGE WOULD FORM...AND CAUSE THURSDAY
TEMPERATURES TO BE 10 TO 20 DEGREES COOLER THAN THE GFS. GIVEN THIS
LARGE DISCREPANCY...CHANCE POPS WERE INTRODUCED FOR THURSDAY...AND
TEMPERATURES WERE BUMPED DOWNWARD BUT KEPT IN THE MIDDLE OF BOTH
SOLUTIONS UNTIL BETTER AGREEMENT IS ESTABLISHED IN FUTURE RUNS.
THE CLIPPER SHOULD EXIT THE CWA AND HEAD SOUTHWARD THROUGH THE
CAROLINAS BY FRIDAY. MEANWHILE...HIGH PRESSURE WILL BUILD OVER THE
MID ATLANTIC FROM THE NORTHWEST. THIS SITUATION SHOULD ALLOW
PLEASANT AND SEASONABLE CONDITIONS FOR THE START OF NEXT WEEKEND.
BOTH THE ECMWF AND GFS KEEP THIS AREA OF HIGH PRESSURE NORTH OF THE
CWA AND SLIDE IT OFF THE EAST COAST BY SUNDAY...WHICH WILL PROMPT A
WARMING TREND AND INCREASING DEWPOINTS FROM RETURN SOUTHERLY FLOW.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 150 AM EDT SUNDAY...
FIRST WAVE OF FRONTAL SHRA/TSRA HAS MOVED EAST OUT OF THE CWA...BUT
SHRA AND EVEN AN ISOLD TSRA OR TWO SPREADING BACK NORTHWARD FROM NC
INTO SW/SC VA IN ASSOCIATION WITH DEEPENING/PHASING UPPER LOW AND
DEVELOPING MID-ATLANTIC COASTAL LOW. EXPECT WIDESPREAD -RA TO SPREAD
ACROSS THE CWA FROM S-N THROUGH 12Z...ESPECIALLY ALONG EAST OF THE
WV/VA LINE OR THE ALLEGHANYS. HEAVIEST/STEADIEST RAIN WILL AFFECT
AREAS ALONG-EAST OF THE BLUE RIDGE...INCLUDING DAN/LYH. CIGS NOW
GENERALLY VFR...BUT WITHIN AN HOUR OR TWO OF THE ONSET OF THE
STEADIER RAIN...EXPECT CIGS TO DROP INTO THE MVFR RANGE...THEN TO
IFR BY 12Z...HOLDING THERE THROUGHOUT MUCH OF THE DAY. VSBYS
GENERALLY MVFR 3-5SM -RA BR ONCE THE STEADIER SETS IN BY 08Z AND
BEYOND. EXCEPTION TO THIS PATTERN WILL BE BLF-LWB...ON BACK SIDE OF
ALLEGHANYS WHERE VSBYS EXPECTED TO REMAIN MVFR -RA BR...BUT WITH
CIGS LOWERING/REMAINING MVFR-IFR. WINDS...NW-NNW AT MOST TAF SITES
AT THE CURRENT TIME. PROGRESSION OF COASTAL LOW SHOULD RESULT IN
WINDS GENERALLY VEERING TO NNE-NE EAST OF THE ALLEGHANYS AND WITH
SLOWLY INCREASING SPEEDS THROUGHOUT THE DAY. AS THE LOW REACHES THE
DELMARVA REGION THIS EVENING...WINDS WILL BACK TO NNW-NW AT ALL TAF
SITES. SPEEDS 10-12KTS WITH GUSTS TO 20KTS THROUGH THE EVENING
HOURS. STRONGER NW WINDS ARE EXPECTED MON...WNW-NW 15-25KTS WITH
GUSTS 30-35KTS AFT 12Z MON.
A MIX OF RAIN AND SNOW SHOWERS WILL AFFECT THE KLWB/KBLF CORRIDOR
LATE SUNDAY NIGHT AND INTO MONDAY. SOME 40-45 KT WIND GUSTS ARE NOT
OUT OF THE QUESTION KROA/KBCB WITH STRONG DOWNSLOPING FLOW INTO
MONDAY. CONDS IMPROVE INTO THE MIDDLE OF NEXT WEEK WITH A CHC FOR
RAIN AND A POTENTIAL WEDGE INTO THURSDAY WITH IFR CIGS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...KM/RAB
NEAR TERM...JH/KM
SHORT TERM...WP
LONG TERM...PM
AVIATION...KM/JH/RAB
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1049 PM CDT MON APR 23 2012
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND TUESDAY.
THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW HIGH
PRESSURE STRETCHING FROM THE SOUTHERN GREAT PLAINS...ACROSS THE
WESTERN GREAT LAKES TO WESTERN HUDSON BAY EARLY THIS AFTERNOON.
VERY DRY AIR JUST OFF THE SURFACE PER 12Z GRB RAOB HAS LED TO
DEWPOINTS PLUMMETING INTO THE SINGLE DIGITS OVER SOME OF THE SANDY
SOIL AREAS OF FAR NE AND NORTH-CENTRAL WISCONSIN. UPSTREAM...PLENTY
OF MID AND HIGH CLOUDS OVER NORTHERN MINNESOTA INTO MANITOBA WHERE
ISENTROPIC ASCENT IS OCCURRING ON THE 295-300K SURFACES. MAIN
FORECAST CONCERNS INCLUDE CLOUD COVERAGE AND PRECIP CHANCES AS THE
UPSTREAM ISENTROPIC ASCENT MOVES INTO WISCONSIN TONIGHT INTO TUESDAY.
TONIGHT...LOW PRESSURE WILL MOVE NORTHEAST INTO SOUTHEAST ONTARIO
WHILE A WEAK AREA OF HIGH PRESSURE WILL REMAINED ANCHORED FROM
HUDSON BAY...ACROSS THE WESTERN GREAT LAKES...TO THE GULF COAST.
MOISTURE WILL CONTINUE TO SPILL OVER TOP OF THE RIDGE CENTERED OVER
THE ROCKIES AND FILTER ACROSS THE STATE FROM WEST TO EAST TONIGHT.
WILL HAVE INCREASING CLOUDS AS A RESULT...BUT NOT ENOUGH TO GO MORE
THAN PARTLY CLOUDY WEST TO MOSTLY CLEAR IN THE EAST. LOWS ARE
TRICKY DUE TO THE DRY AIRMASS IN PLACE YET WILL HAVE INCREASING
CLOUDS. WILL GO WITH LOWS RANGING FROM THE UPPER 20S NORTH TO UPPER
30S SOUTHEAST.
TUESDAY...850MB WARM FRONT WILL MOVE INTO THE NORTHERN MISSISSIPPI
VALLEY WHILE MID-LEVEL MOISTURE FROM THE LAKE WINNIPEG REGION WILL
SLIDE SOUTHEAST ACROSS THE AREA DURING THE MORNING. AS DIURNAL
HEATING OCCURS...WILL SEE CAPES BETWEEN 50-100 J/KG DEVELOP THAT
SHOULD HELP FILL IN WHATEVER HOLES THERE ARE IN THE CLOUD DECK.
WOULDNT BE SURPRISED TO SEE MOSTLY CLOUDY CONDITIONS DEVELOP BY
MIDDAY...BUT WILL GO WITH PARTLY SUNNY WORDING INSTEAD TO BLEND WITH
SURROUNDING OFFICES. BOTH THE NAM AND GFS TRIGGER LIGHT QPF OVER EASTERN
WISCONSIN. THINK THIS IS A TOO PESSIMISTIC...AS ITS TOUGH TO FIND A
TRIGGER...AND INSTABILITY IS PRETTY MEAGER. SO WILL STAY WITH A DRY
FORECAST. DRIER AIR DOES RETURN FROM THE NORTH DURING THE
AFTERNOON...SO SHOULD SEE AT LEAST PARTIAL CLEARING ARRIVE. HIGHS
ROUGHLY ABOUT 4 DEGREES WARMER THAN TODAY...FROM THE UPPER 50S NORTH
TO MIDDLE 60S SOUTH.
.LONG TERM...TUESDAY NIGHT THROUGH NEXT MONDAY...MAIN FCST CONCERNS
ARE PCPN TRENDS FOR THE MIDWEEK PERIOD AND NEXT WEEKEND.
LOW PRESSURE OVER THE NORTHERN PLAINS ON TUESDAY EVG IS EXPECTED TO
SHIFT SE TOWARD ILLINOIS ON WEDNESDAY. A FAIRLY STG BAROCLINIC
ZONE WILL SET UP OVER THE REGION...WITH ISENT LIFT DEVELOPING LATE
TUESDAY NIGHT INTO WEDNESDAY AS LLVL FLOW BECOMES SW AHEAD OF AN
APPROACHING COLD FRONT. IN ADDITION...SOME SHORT-WAVE ENERGY AND THE
RRQ OF AN UPPER JET STREAK WILL BE PULLING THROUGH THE AREA. HAVE
KEPT CHC POPS FOR OUR SW COUNTIES AFTER MIDNIGHT TUESDAY NIGHT...
THEN ADJUSTED PCPN TRENDS AS PCPN SPREADS NORTHEAST ON WEDNESDAY.
RAISED POPS INTO THE LIKELY CATEGORY OVER ABOUT THE SW TWO-THIRDS
OF THE CWA ON WEDS. ALSO ADDED A CHC OF TSTMS ON WEDS AFTERNOON AS
MODELS SHOW A BAND OF INSTABILITY DEVELOPING IN ADVANCE OF THE
COLD FRONT. THIS FRONT SHOULD GENERATE SOME SHOWERS INTO WEDS
NIGHT...ESPECIALLY DURING THE EVG.
CANADIAN HIGH PRESSURE WILL BUILD INTO THE REGION IN THE WAKE OF
THE COLD FRONT ON THURSDAY AND FRIDAY...BRINGING DRY AND COOLER
CONDITIONS. SUB-FREEZING TEMPERATURES WILL ONCE AGAIN BE POSSIBLE ON
THURSDAY NIGHT.
A BATTLE OF THE AIR MASSES IS SETTING UP FOR THE WEEKEND...WITH
DRY CANADIAN HIGH PRESSURE STILL RIDGED TO OUR NORTH...AND LOW
PRESSURE AND ABUNDANT MOISTURE TRACKING THROUGH THE UPPER MIDWEST.
AS THE LOW PASSES TO OUR SOUTH...EXPECT NE WINDS TO INCREASE...
WHICH SHOULD REINFORCE THE DRY AIR OVER AT LEAST NORTHERN WI.
WILL CARRY SOME LOW CHANCE POPS OVER MAINLY OUR SOUTHERN COUNTIES
SATURDAY INTO SUNDAY...BUT WOULD NOT BE SURPRISED IF THE DRY AIR
EVENTUALLY WINS THIS BATTLE.
THE CANADIAN HIGH IS EXPECTED TO SAG SOUTH OVER THE REGION AGAIN
LATER SUNDAY INTO MONDAY...WITH ASSOCIATED DRY CONDITIONS.
&&
.AVIATION...A VFR CIG WILL PASS OVER PARTS OF CENTRAL WISCONSIN
OVERNIGHT OTHERWISE VFR CONDITIONS TO PREVAIL THROUGH TUESDAY.
GUSTY NORTHWEST WINDS MAY OCCUR AGAIN TUESDAY AFTERNOON OVER FAR
EASTERN WISCONSIN.
TDH
&&
.MARINE...A TIGHTENING PRESSURE GRADIENT WILL LEAD TO NEAR SMALL
CRAFT ADVISORY WIND GUSTS OVER THE NEARSHORE WATERS THIS EVENING.
THE AREA AROUND DEATHS DOOR WILL BE THE MOST PRONE FOR THESE HIGHER
GUSTS.
&&
.FIRE WEATHER...DRY AIR JUST OFF THE SURFACE PER 12Z GRB RAOB HAS
LED TO RH/S CRASHING TO THE 10-15 PCT RANGE OVER MUCH OF FAR
NORTHEAST AND NORTH-CENTRAL WISCONSIN. WITH WIND GUSTS UP TO 20
KTS...WILL CONTINUE TO MENTION AN ELEVATED FIRE DANGER IN THE HWO.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
302 PM CDT SUN APR 22 2012
.SHORT TERM...TONIGHT AND MONDAY.
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A LOW PRESSURE
SYSTEM MOVING NORTH ALONG THE MID-ATLANTIC COASTLINE...WHILE SURFACE
HIGH PRESSURE STRETCHES FROM NORTHERN QUEBEC TO LAKE SUPERIOR...AND
SOUTH ACROSS THE GREAT PLAINS. A SURFACE TROUGH HAS REMAINED NEARLY
STATIONARY FROM NORTHERN MINNESOTA TO THE CENTRAL MISSISSIPPI RIVER
VALLEY...WHERE BKN-OVC LOW AND MID CLOUDS RESIDE. DRY NE WINDS
HAVE ERODED MUCH OF THE CLOUD COVER OVER NORTH-CENTRAL WISCONSIN
LEAVING ONLY FEW TO SCT CONDITIONS FROM WAUSAU TO LAND O LAKES.
WITH SURFACE FEATURES MOVING VERY LITTLE OVER THE NEXT 24
HOURS...CLOUD COVER AND TEMPS AND HUMIDITIES ARE THE MAIN FORECAST
CONCERNS.
TONIGHT...CLOSED UPPER LOW OVER THE OHIO VALLEY WILL SWING EAST TO
THE MID-ATLANTIC STATES TONIGHT. MEANWHILE...AREA OF HIGH PRESSURE
STRETCHING FROM THE NORTHERN PLAINS TO JAMES BAY WILL DRIFT SLIGHTLY
SOUTHWARD OVER THE WESTERN GREAT LAKES. PESKY AREA OF MID AND HIGH
CLOUDS OVER THE NORTHERN MISSISSIPPI VALLEY WILL ALSO SINK SOUTH AND
WILL PROVIDE SCT TO BKN CONDITIONS OVER THE WESTERN HALF OF THE
FORECAST AREA. NO REAL THREAT OF PRECIP FROM THESE CLOUDS.
OTHERWISE...QUIET CONDITIONS WITH LIGHT WINDS WILL BE IN PLACE. LOW
TEMPS RANGING FROM THE UPPER 20S NORTH TO MID 30S SOUTH.
MONDAY...HIGH PRESSURE WILL REMAIN IN PLACE ACROSS THE AREA...BUT
THE PRESSURE GRADIENT WILL TIGHTEN AS A RESULT OF LOW PRESSURE
MOVING NE ACROSS NEW ENGLAND. WILL SEE MOSTLY SUNNY AND WARMER
CONDITIONS...THOUGH WITH A GUSTY NORTH WINDS DEVELOPING IN THE
AFTERNOON. HIGHS MID 50S NORTH TO AROUND 60 DEGREES SOUTH.
.LONG TERM...MONDAY NIGHT THROUGH NEXT SUNDAY...MAIN FCST CONCERNS
ARE PCPN TRENDS FOR THE MIDWEEK PERIOD AND NEXT WEEKEND.
NW FLOW WILL PREVAIL OVER WISCONSIN EARLY IN THE PERIOD...WITH A
STRONG UPPER RIDGE OVER THE ROCKIES AND AN UPPER LOW LIFTING FROM THE
EASTERN GREAT LAKES INTO QUEBEC. WEAK SFC HIGH PRESSURE SHOULD KEEP
GRB CWA DRY MONDAY NIGHT AND TUESDAY.
LOW PRESSURE OVER THE NORTHERN PLAINS ON TUESDAY EVG IS EXPECTED TO
SHIFT SE INTO ILLINOIS ON WEDNESDAY. A COUPLE JET STREAKS WILL
PASS OVER WI...PUTTING PART OF THE FCST AREA IN THE RRQ. A FAIRLY
STG BAROCLINIC ZONE WILL SET UP OVER THE REGION...WITH ISENT LIFT
DEVELOPING AS LLVL FLOW BECOMES S-SW AHEAD OF AN APPROACHING COLD
FRONT. HAVE CONTINUED WITH THE TREND OF HIGHEST POPS OVER OUR SW
COUNTIES...WHERE BEST MOISTURE...LIFT AND INSTABILITY IS EXPECTED.
WEAK HIGH PRESSURE AND ASSOCIATED DRY AIR WILL ALSO BE SLOW TO
PULL OUT OF NE WI. ALTHOUGH TIMING OF THE MAIN COLD FRONT IS A
QUESTION MARK RIGHT NOW...THE GENERAL CONCENSUS IS THAT IT SHOULD
MOVE THROUGH THE AREA WEDS AFTERNOON AND EVENING. SOME SHOWERS
MAY ALSO BE GENERATED WITH THIS FEATURE.
STRONG CANADIAN HIGH PRESSURE WILL BUILD INTO THE REGION ON
THURSDAY...AND LIKELY LINGER INTO AT LEAST THE EARLY PART OF THE
WEEKEND. FREEZING TEMPERATURES WILL ONCE AGAIN BE POSSIBLE...WITH
THE BEST CHANCE OCCURRING ON THURSDAY NIGHT.
MODELS ARE HAVING DIFFICULTY DETERMINING HOW LONG THE CANADIAN HIGH
WILL PERSIST OVER THE REGION...AND THE TIMING OF AN UPPER TROF
APPROACHING FROM THE PLAINS. THE ECMWF HAS BEEN MORE AGGRESSIVE
BRINGING PCPN INTO THE REGION OVER THE PAST COUPLE DAYS. FOR NOW...
HAVE REMOVED ANY POPS FROM THE SATURDAY FCST...AND KEPT LOW POPS
SAT NGT INTO SUNDAY.
&&
.AVIATION... SCT TO BKN MID AND HIGH CLOUDS WILL GRADUALLY SINK
SOUTH ACROSS WESTERN AND CENTRAL WISCONSIN THROUGH THIS EVENING
BEFORE DEPARTING LATE TONIGHT. THE PRESSURE GRADIENT WILL TIGHTEN
UP ON MONDAY AS DEEP LOW PRESSURE MOVES NORTH OVER THE
APPALACHIANS. WILL SEE NORTH WINDS STRENGTHEN AND BECOME GUSTY BY
MIDDAY ON MONDAY BUT CONDITIONS TO REMAIN VFR THROUGH MONDAY
AFTERNOON.
MPC
&&
.MARINE...THE PRESSURE GRADIENT WILL TIGHTEN TOMORROW AFTERNOON
BETWEEN HIGH PRESSURE OVER THE NORTHERN PLAINS AND LOW PRESSURE OVER
NEW ENGLAND. DO NOT HAVE MUCH INSTABILITY OVER NORTHERN LAKE
MICHIGAN...BUT THE PRESSURE GRADIENT ALONE MAY BE ABLE TO CREATE
SMALL CRAFT CRITERIA WINDS TOMORROW AFTERNOON.
&&
.FIRE WEATHER...AS LOW PRESSURE MOVES NE OVER NEW ENGLAND
TOMORROW...GUSTY NORTH WINDS WILL DEVELOP MONDAY AFTERNOON. THE
PRESSURE GRADIENT WILL BE TIGHTER OVER EASTERN WISCONSIN...WHERE
GUSTS TO AROUND 25 KTS WILL BE POSSIBLE. HIGHER DEWPOINTS FROM
WESTERN WISCONSIN WILL MIGRATE INTO CENTRAL WISCONSIN TOMORROW
AFTERNOON...WHILE NE WISCONSIN WILL SEE THE BEST MIXING AND HAVE
ACCESS TO THE DRIEST AIR. HUMIDITIES MAY FALL INTO THE 15-20 PCT
RANGE OVER THE SANDY SOIL AREAS OF NE WISCONSIN IN THE AFTERNOON
WHERE CRITICAL LEVELS WILL BE REACH FOR HUMIDITY AND WINDS.
TEMPERATURES WILL OBVIOUSLY FALL WELL SHORT EVERYWHERE. AFTER
COORDINATING WITH THE FOREST SERVICE...CONDITIONS ARE A BIT OF
STRETCH FOR A FIRE WEATHER WATCH TOMORROW AFTERNOON.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MPC/KIECKBUSCH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1236 PM CDT SUN APR 22 2012
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
300 AM CDT SUN APR 22 2012
MAIN FORECAST CONCERNS ARE ON THE NEXT PRECIPITATION CHANCES FOR
TUESDAY NIGHT.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS
SHOWED STRONG RIDGING OVER THE WESTERN U.S. BUILDING INTO SOUTHWEST
CANADA...WHILE TROUGHING WAS PRESENT FROM THE WESTERN GREAT LAKES
REGION SOUTH INTO FLORIDA. MAIN FEATURES OF NOTE TRAVERSING THROUGH
THE TROUGH INCLUDE: AN UPPER LOW NEAR FLORIDA...A POTENT SHORTWAVE
OVER SOUTHWEST IOWA...AND ANOTHER SHORTWAVE IN EASTERN NORTH DAKOTA.
THE POTENT SHORTWAVE HAS BEEN RESPONSIBLE FOR MUCH OF THE
PRECIPITATION AFFECTING THE WESTERN PORTION OF THE FORECAST AREA THE
PAST 18 HOURS...AN IN PARTICULAR A LOW TO MID LEVEL FRONTOGENESIS
ZONE AHEAD OF IT. RUC ANALYSIS SHOWED THIS FRONTOGENESIS HAS DROPPED
SOUTH INTO EASTERN IOWA...AND AS SUCH THE SHOWERS HAVE BEEN
WEAKENING OVER THE FORECAST AREA OVERNIGHT. ANOTHER FEATURE ALLOWING
PRECIPITATION TO WEAKEN IS AN AREA OF HIGH PRESSURE OVER NORTHEAST
ONTARIO. EASTERLY WINDS ARE ADVECTING DRIER AIR OUT OF THE HIGH INTO
THE FORECAST AREA...PARTICULARLY WISCONSIN. 00Z GRB SOUNDING HAD A
PRECIPITABLE WATER OF 0.26 INCHES. THE EASTERLY WINDS STOP AT AN
INVERTED TROUGH WHICH EXTENDS FROM JUST WEST OF MINNEAPOLIS SOUTH
INTO SOUTHEAST IOWA. AIRMASS REMAINS SEASONABLY COOL OVER THE AREA
WITH 850MB TEMPS BETWEEN 0 AND -2C PER 00Z RAOB ANALYSIS.
TODAY THROUGH MONDAY...OVER THE NEXT 24 TO 36 HOURS...A FAIRLY DEEP
TROUGH IS GOING TO FORM OVER THE EASTERN THIRD OF THE U.S....IN
RESPONSE TO THE CURRENT POTENT SHORTWAVE IN IOWA PHASING WITH THE
UPPER LOW IN FLORIDA. IN RESPONSE TO THIS PHASING...A STRONG SPRING
STORM WILL FORM OVER THE NORTHEAST. FOR THE FORECAST AREA...PLAN ON
MAINLY QUIET WEATHER AS HIGH PRESSURE OVER NORTHERN ONTARIO SLOWLY
SINKS SOUTH. THERE ARE STILL SOME ISSUES TO DEAL WITH...THOUGH. THE
FIRST OF WHICH IS THE LINGERING PRECIPITATION AND INVERTED TROUGH.
AS TODAY WEARS ON...THE INVERTED TROUGH SHOULD CONTINUE TO WEAKEN...
ESPECIALLY THIS EVENING WHEN THE SHORTWAVE OVER EASTERN NORTH DAKOTA
SLIDES SOUTH OF THE AREA. ISOLATED/SCATTERED SHOWERS SEEM POSSIBLE
TODAY NEAR THE INVERTED TROUGH...AIDED BY FOCUSED LOW LEVEL
CONVERGENCE AND MOISTURE. MAINTAINED SOME 20 PERCENT CHANCES IN THE
VERY FAR WESTERN PORTION OF THE FORECAST AREA THIS MORNING...IN
AGREEMENT WITH THE 22.00Z NAM/GFS AND LATEST HRRR RUNS. FOR THE REST
OF THE FORECAST AREA TODAY...AN INCREASING NORTHEAST FLOW WILL HELP
BRING IN LOW LEVEL DRY AIR. SOME CLEARING IS POSSIBLE...ESPECIALLY
OVER THE SOUTHEAST END OF THE AREA. TONIGHT...ALTHOUGH THE HIGH
PRESSURE AREA IS MOVING IN...THE NORTHWEST FLOW ALOFT SHOULD HELP
CARRY LOW TO MID LEVEL STRATUS SEEN OVER THE DULUTH AREA SOUTH
ACROSS THE FORECAST AREA. THESE CLOUDS SHOULD BE ENOUGH TO PREVENT
TEMPERATURES FROM REACHING A FROST/FREEZE SITUATION. SKIES ARE
EXPECTED TO CLEAR OUT MONDAY MORNING...THEN ANOTHER SURGE OF MID TO
HIGH CLOUDS ENTER THE PICTURE FROM THE NORTH IN THE AFTERNOON. THIS
IS ASSOCIATED WITH A SMALL PORTION OF THE WESTERN UPPER RIDGE THAT
IS PROGGED TO BUILD TOWARDS THE FORECAST AREA. WE WILL FEEL THIS TOO
BY AN INCREASE IN TEMPERATURES. 850MB TEMPS ARE ONLY 0 TO -2C
TODAY...RESULTING IN HIGHS ONLY IN THE MID 50S. HOWEVER...BY 00Z
TUESDAY...THEY CLIMB TO 2-4C...ALLOWING FOR HIGHS IN THE UPPER 50S
TO LOW 60S.
MONDAY NIGHT THROUGH TUESDAY NIGHT...FOCUS TURNS TO A LOW PRESSURE
SYSTEM PROGGED TO DEVELOP OVER SOUTH CENTRAL SASKATCHEWAN AT 00Z
TUESDAY...ON TOP OF THE UPPER RIDGE. VERY GOOD MODEL AGREEMENT
EXISTS THAT THE UPPER RIDGE WILL FLATTEN AND GET PUSHED SOUTH...IN
RESPONSE TO A SHORTWAVE ROUNDING THE RIDGE WHICH IS LOCATED OFF BAJA
CALIFORNIA RIGHT NOW. AS THE RIDGE FLATTENS...THE LOW PRESSURE
SYSTEM GETS SENT SOUTHEASTWARD INTO WESTERN IOWA BY 12Z WEDNESDAY.
WARM ADVECTION IS FORECAST AHEAD OF THE LOW OVER THE FORECAST AREA
DURING THE ENTIRE MONDAY NIGHT THROUGH TUESDAY NIGHT. 850MB TEMPS
RESPOND BY CLIMBING TO 6 TO 12C BY 00Z WEDNESDAY...WARMEST IN THE
FAR WESTERN PORTION OF THE FORECAST AREA. EVEN MORE WARMING IS
POSSIBLE TUESDAY NIGHT. THE BIGGER QUESTION...THOUGH...IS WHEN/IF
PRECIPITATION WILL OCCUR. PRECIPITABLE WATER VALUES START OFF FAIRLY
LOW AT 00Z TUESDAY...NEAR A 0.5 INCH. GOOD AGREEMENT EXISTS THAT
THESE WILL SLOWLY CLIMB TO NEAR AN INCH BY 00Z WEDNESDAY.
STILL...ISENTROPIC LIFT IS NOT ALL THAT IMPRESSIVE...SUGGESTING MUCH
OF THE WARM ADVECTION IS JUST GOING INTO WARMING. LIKELY TO SEE AN
INCREASE IN MID AND HIGH CLOUDS...THOUGH. THESE CLOUDS WILL HELP TO
KEEP TEMPERATURES UP MONDAY NIGHT. WITH A WARMER START TO
TUESDAY...INCREASING 850MB TEMPS AND FILTERED SUN...ANTICIPATING
HIGHS AT LEAST IN THE 60S AND POSSIBLY LOW 70S IN THE FAR WEST. BY
TUESDAY NIGHT...WITH THE LOW APPROACHING...THERE IS SOME SUGGESTION
OF LOW TO MID LEVEL FRONTOGENESIS INCREASING. THEREFORE...CHANCES OF
PRECIPITATION ARE NECESSARY TUESDAY NIGHT. DO NOT HAVE CONFIDENCE AT
THIS TIME TO GO HIGHER THAN 50 PERCENT AS WOULD LIKE TO SEE STRONGER
FORCING SIGNALS. WILL CONTINUE TO MENTION THUNDER WITH A PLUME OF
500-1000 J/KG OF MUCAPE ADVECTING INTO THE FRONTOGENESIS ZONE.
.LONG TERM...WEDNESDAY THROUGH SATURDAY NIGHT
300 AM CDT SUN APR 22 2012
22.00Z ECMWF/GFS/CANADIAN AND GFS ENSEMBLES ARE IN PRETTY GOOD
AGREEMENT THROUGH THE ENTIRE LONG TERM PERIOD WITH BOTH THE UPPER
LEVEL AND SURFACE PATTERNS. FOR MUCH OF THE LONG TERM PERIOD...THE
FORECAST AREA IS UNDER THE INFLUENCE OF A CANADIAN HIGH PRESSURE
AREA WHICH DROPS DOWN INTO THE WESTERN GREAT LAKES REGION THURSDAY
MORNING. PRIOR TO THEN...THE LOW PRESSURE SYSTEM FROM TUESDAY NIGHT
AND THE FRONTOGENESIS ZONE AHEAD OF IT OVER THE AREA SHOULD REMAIN
MOSTLY IN PLACE ON WEDNESDAY...THEN HEAD OFF TO THE EAST WEDNESDAY
NIGHT. MAINTAINED 20-40 PERCENT CHANCES ON WEDNESDAY...HIGHEST
ALONG/SOUTH OF I-90...THEN JUST A 20 PERCENT CHANCE WEDNESDAY NIGHT
FOR THE DEPARTING PRECIPITATION. DRY AND COOLER CONDITIONS
ANTICIPATED FOR THURSDAY THROUGH FRIDAY WITH THAT CANADIAN HIGH
BUILDING DOWN. WENT TOWARDS THE COLD SIDE OF GUIDANCE FOR LOWS
THURSDAY NIGHT...WHERE FREEZE CONDITIONS SEEM LIKELY ALONG AND
NORTH OF I-94. WILL REALLY HAVE TO WATCH THIS NIGHT TEMPERATURE
WISE...GIVEN DEWPOINTS THAT ARE LIKELY TO DROP INTO THE 20S AND
MAYBE EVEN UPPER TEENS. AN UPPER RIDGE ON THE WEST SIDE OF THE
SURFACE HIGH IS ALSO A FEATURE TO WATCH. RIGHT NOW GOOD AGREEMENT
EXISTS THAT THIS UPPER RIDGE GET PUSHED INTO THE AREA ON SATURDAY
AS TROUGHING DEVELOPS OVER MUCH OF THE WESTERN U.S.. WILL SEE IF
THAT PROGRESSION STAYS...BUT WITH THAT RIDGE MOVING IN MEANS WARM
ADVECTION...AND THEREFORE CHANCES OF SHOWERS AND THUNDERSTORMS
ENTER THE PICTURE. SEEMS LIKE THE BETTER CHANCES FOR RAIN WOULD
COME SATURDAY NIGHT AND SUNDAY AS SHORTWAVES EJECT OUT OF THE
WESTERN TROUGH AND MOVE INTO THE AREA.
&&
.AVIATION...THROUGH 18Z MONDAY
1236 PM CDT SUN APR 22 2012
HIGH PRESSURE WILL MAINTAIN VFR CONDITIONS AT THE TAF SITES
THROUGH THE FORECAST PERIOD. LOOK FOR SCT-BKN CUMULUS CLOUDS TODAY
WITH CLOUD BASES AROUND 5 KFT. A WEAK MID LEVEL IMPULSE WILL DRIFT
SOUTH ACROSS THE AREA THIS EVENING BRINGING A BROKEN STRATUS DECK
ACROSS THE TAF SITES WITH CLOUDS BASES IN THE 5 TO 7 KFT RANGE.
LOOK FOR THESE CLOUDS TO BECOME SCATTERED AFTER 07Z. LOW PRESSURE
WILL EDGE INTO EASTERN LOWER MICHIGAN AS A SURFACE RIDGE OF HIGH
PRESSURE REMAINS ANCHORED ACROSS CENTRAL MINNESOTA INTO NORTHERN
MISSOURI. LOOK FOR WINDS TO SWITCH TO THE NORTH/NORTHWEST LATE
TONIGHT INTO MONDAY...INTO THE 10 TO 13 KT RANGE. WIND GUSTS TO
AROUND 20 KTS ARE POSSIBLE AT KLSE LATE MONDAY MORNING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
300 AM CDT SUN APR 22 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM....AJ
AVIATION.....WETENKAMP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
631 AM CDT SUN APR 22 2012
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
300 AM CDT SUN APR 22 2012
MAIN FORECAST CONCERNS ARE ON THE NEXT PRECIPITATION CHANCES FOR
TUESDAY NIGHT.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS
SHOWED STRONG RIDGING OVER THE WESTERN U.S. BUILDING INTO SOUTHWEST
CANADA...WHILE TROUGHING WAS PRESENT FROM THE WESTERN GREAT LAKES
REGION SOUTH INTO FLORIDA. MAIN FEATURES OF NOTE TRAVERSING THROUGH
THE TROUGH INCLUDE: AN UPPER LOW NEAR FLORIDA...A POTENT SHORTWAVE
OVER SOUTHWEST IOWA...AND ANOTHER SHORTWAVE IN EASTERN NORTH DAKOTA.
THE POTENT SHORTWAVE HAS BEEN RESPONSIBLE FOR MUCH OF THE
PRECIPITATION AFFECTING THE WESTERN PORTION OF THE FORECAST AREA THE
PAST 18 HOURS...AN IN PARTICULAR A LOW TO MID LEVEL FRONTOGENESIS
ZONE AHEAD OF IT. RUC ANALYSIS SHOWED THIS FRONTOGENESIS HAS DROPPED
SOUTH INTO EASTERN IOWA...AND AS SUCH THE SHOWERS HAVE BEEN
WEAKENING OVER THE FORECAST AREA OVERNIGHT. ANOTHER FEATURE ALLOWING
PRECIPITATION TO WEAKEN IS AN AREA OF HIGH PRESSURE OVER NORTHEAST
ONTARIO. EASTERLY WINDS ARE ADVECTING DRIER AIR OUT OF THE HIGH INTO
THE FORECAST AREA...PARTICULARLY WISCONSIN. 00Z GRB SOUNDING HAD A
PRECIPITABLE WATER OF 0.26 INCHES. THE EASTERLY WINDS STOP AT AN
INVERTED TROUGH WHICH EXTENDS FROM JUST WEST OF MINNEAPOLIS SOUTH
INTO SOUTHEAST IOWA. AIRMASS REMAINS SEASONABLY COOL OVER THE AREA
WITH 850MB TEMPS BETWEEN 0 AND -2C PER 00Z RAOB ANALYSIS.
TODAY THROUGH MONDAY...OVER THE NEXT 24 TO 36 HOURS...A FAIRLY DEEP
TROUGH IS GOING TO FORM OVER THE EASTERN THIRD OF THE U.S....IN
RESPONSE TO THE CURRENT POTENT SHORTWAVE IN IOWA PHASING WITH THE
UPPER LOW IN FLORIDA. IN RESPONSE TO THIS PHASING...A STRONG SPRING
STORM WILL FORM OVER THE NORTHEAST. FOR THE FORECAST AREA...PLAN ON
MAINLY QUIET WEATHER AS HIGH PRESSURE OVER NORTHERN ONTARIO SLOWLY
SINKS SOUTH. THERE ARE STILL SOME ISSUES TO DEAL WITH...THOUGH. THE
FIRST OF WHICH IS THE LINGERING PRECIPITATION AND INVERTED TROUGH.
AS TODAY WEARS ON...THE INVERTED TROUGH SHOULD CONTINUE TO WEAKEN...
ESPECIALLY THIS EVENING WHEN THE SHORTWAVE OVER EASTERN NORTH DAKOTA
SLIDES SOUTH OF THE AREA. ISOLATED/SCATTERED SHOWERS SEEM POSSIBLE
TODAY NEAR THE INVERTED TROUGH...AIDED BY FOCUSED LOW LEVEL
CONVERGENCE AND MOISTURE. MAINTAINED SOME 20 PERCENT CHANCES IN THE
VERY FAR WESTERN PORTION OF THE FORECAST AREA THIS MORNING...IN
AGREEMENT WITH THE 22.00Z NAM/GFS AND LATEST HRRR RUNS. FOR THE REST
OF THE FORECAST AREA TODAY...AN INCREASING NORTHEAST FLOW WILL HELP
BRING IN LOW LEVEL DRY AIR. SOME CLEARING IS POSSIBLE...ESPECIALLY
OVER THE SOUTHEAST END OF THE AREA. TONIGHT...ALTHOUGH THE HIGH
PRESSURE AREA IS MOVING IN...THE NORTHWEST FLOW ALOFT SHOULD HELP
CARRY LOW TO MID LEVEL STRATUS SEEN OVER THE DULUTH AREA SOUTH
ACROSS THE FORECAST AREA. THESE CLOUDS SHOULD BE ENOUGH TO PREVENT
TEMPERATURES FROM REACHING A FROST/FREEZE SITUATION. SKIES ARE
EXPECTED TO CLEAR OUT MONDAY MORNING...THEN ANOTHER SURGE OF MID TO
HIGH CLOUDS ENTER THE PICTURE FROM THE NORTH IN THE AFTERNOON. THIS
IS ASSOCIATED WITH A SMALL PORTION OF THE WESTERN UPPER RIDGE THAT
IS PROGGED TO BUILD TOWARDS THE FORECAST AREA. WE WILL FEEL THIS TOO
BY AN INCREASE IN TEMPERATURES. 850MB TEMPS ARE ONLY 0 TO -2C
TODAY...RESULTING IN HIGHS ONLY IN THE MID 50S. HOWEVER...BY 00Z
TUESDAY...THEY CLIMB TO 2-4C...ALLOWING FOR HIGHS IN THE UPPER 50S
TO LOW 60S.
MONDAY NIGHT THROUGH TUESDAY NIGHT...FOCUS TURNS TO A LOW PRESSURE
SYSTEM PROGGED TO DEVELOP OVER SOUTH CENTRAL SASKATCHEWAN AT 00Z
TUESDAY...ON TOP OF THE UPPER RIDGE. VERY GOOD MODEL AGREEMENT
EXISTS THAT THE UPPER RIDGE WILL FLATTEN AND GET PUSHED SOUTH...IN
RESPONSE TO A SHORTWAVE ROUNDING THE RIDGE WHICH IS LOCATED OFF BAJA
CALIFORNIA RIGHT NOW. AS THE RIDGE FLATTENS...THE LOW PRESSURE
SYSTEM GETS SENT SOUTHEASTWARD INTO WESTERN IOWA BY 12Z WEDNESDAY.
WARM ADVECTION IS FORECAST AHEAD OF THE LOW OVER THE FORECAST AREA
DURING THE ENTIRE MONDAY NIGHT THROUGH TUESDAY NIGHT. 850MB TEMPS
RESPOND BY CLIMBING TO 6 TO 12C BY 00Z WEDNESDAY...WARMEST IN THE
FAR WESTERN PORTION OF THE FORECAST AREA. EVEN MORE WARMING IS
POSSIBLE TUESDAY NIGHT. THE BIGGER QUESTION...THOUGH...IS WHEN/IF
PRECIPITATION WILL OCCUR. PRECIPITABLE WATER VALUES START OFF FAIRLY
LOW AT 00Z TUESDAY...NEAR A 0.5 INCH. GOOD AGREEMENT EXISTS THAT
THESE WILL SLOWLY CLIMB TO NEAR AN INCH BY 00Z WEDNESDAY.
STILL...ISENTROPIC LIFT IS NOT ALL THAT IMPRESSIVE...SUGGESTING MUCH
OF THE WARM ADVECTION IS JUST GOING INTO WARMING. LIKELY TO SEE AN
INCREASE IN MID AND HIGH CLOUDS...THOUGH. THESE CLOUDS WILL HELP TO
KEEP TEMPERATURES UP MONDAY NIGHT. WITH A WARMER START TO
TUESDAY...INCREASING 850MB TEMPS AND FILTERED SUN...ANTICIPATING
HIGHS AT LEAST IN THE 60S AND POSSIBLY LOW 70S IN THE FAR WEST. BY
TUESDAY NIGHT...WITH THE LOW APPROACHING...THERE IS SOME SUGGESTION
OF LOW TO MID LEVEL FRONTOGENESIS INCREASING. THEREFORE...CHANCES OF
PRECIPITATION ARE NECESSARY TUESDAY NIGHT. DO NOT HAVE CONFIDENCE AT
THIS TIME TO GO HIGHER THAN 50 PERCENT AS WOULD LIKE TO SEE STRONGER
FORCING SIGNALS. WILL CONTINUE TO MENTION THUNDER WITH A PLUME OF
500-1000 J/KG OF MUCAPE ADVECTING INTO THE FRONTOGENESIS ZONE.
.LONG TERM...WEDNESDAY THROUGH SATURDAY NIGHT
300 AM CDT SUN APR 22 2012
22.00Z ECMWF/GFS/CANADIAN AND GFS ENSEMBLES ARE IN PRETTY GOOD
AGREEMENT THROUGH THE ENTIRE LONG TERM PERIOD WITH BOTH THE UPPER
LEVEL AND SURFACE PATTERNS. FOR MUCH OF THE LONG TERM PERIOD...THE
FORECAST AREA IS UNDER THE INFLUENCE OF A CANADIAN HIGH PRESSURE
AREA WHICH DROPS DOWN INTO THE WESTERN GREAT LAKES REGION THURSDAY
MORNING. PRIOR TO THEN...THE LOW PRESSURE SYSTEM FROM TUESDAY NIGHT
AND THE FRONTOGENESIS ZONE AHEAD OF IT OVER THE AREA SHOULD REMAIN
MOSTLY IN PLACE ON WEDNESDAY...THEN HEAD OFF TO THE EAST WEDNESDAY
NIGHT. MAINTAINED 20-40 PERCENT CHANCES ON WEDNESDAY...HIGHEST
ALONG/SOUTH OF I-90...THEN JUST A 20 PERCENT CHANCE WEDNESDAY NIGHT
FOR THE DEPARTING PRECIPITATION. DRY AND COOLER CONDITIONS
ANTICIPATED FOR THURSDAY THROUGH FRIDAY WITH THAT CANADIAN HIGH
BUILDING DOWN. WENT TOWARDS THE COLD SIDE OF GUIDANCE FOR LOWS
THURSDAY NIGHT...WHERE FREEZE CONDITIONS SEEM LIKELY ALONG AND
NORTH OF I-94. WILL REALLY HAVE TO WATCH THIS NIGHT TEMPERATURE
WISE...GIVEN DEWPOINTS THAT ARE LIKELY TO DROP INTO THE 20S AND
MAYBE EVEN UPPER TEENS. AN UPPER RIDGE ON THE WEST SIDE OF THE
SURFACE HIGH IS ALSO A FEATURE TO WATCH. RIGHT NOW GOOD AGREEMENT
EXISTS THAT THIS UPPER RIDGE GET PUSHED INTO THE AREA ON SATURDAY
AS TROUGHING DEVELOPS OVER MUCH OF THE WESTERN U.S.. WILL SEE IF
THAT PROGRESSION STAYS...BUT WITH THAT RIDGE MOVING IN MEANS WARM
ADVECTION...AND THEREFORE CHANCES OF SHOWERS AND THUNDERSTORMS
ENTER THE PICTURE. SEEMS LIKE THE BETTER CHANCES FOR RAIN WOULD
COME SATURDAY NIGHT AND SUNDAY AS SHORTWAVES EJECT OUT OF THE
WESTERN TROUGH AND MOVE INTO THE AREA.
&&
.AVIATION...TODAY AND TONIGHT
631 AM CDT SUN APR 22 2012
RATHER QUIET VFR WEATHER PERIOD TODAY/TONIGHT WITH HIGH PRESSURE
SLOWLY BUILDING SOUTH INTO THE AREA. DRIER EAST/NORTHEAST LOW LEVEL
FLOW WILL SLOWLY ERODE THE CLOUDS WITH RISING SCT-BKN CLOUD LAYERS
TODAY. WITH STEEP LOW LEVEL LAPSE RATES AND SOME LINGERING MOISTURE
THIS AFTERNOON...SCT 5K-6K FT CU/STRATO-CU EXPECTED FOR THE LATE
MORNING/ AFTERNOON HOURS. BKN MID CLOUD DECKS WILL COVER THE AREA
THIS EVENING AS SOME MID LEVEL MOISTURE STUCK IN THE WEAK NORTHERLY
FLOW DRIFTS SOUTH ACROSS THE AREA. DEEPER/DRIER AIR PUSHES SOUTH
ACROSS THE AREA LATER TONIGHT AS SOME STRONGER NORTHERLY MID LEVEL
FLOW AND 850-500MB SHORTWAVE RIDGING BUILDS INTO THE UPPER MIDWEST.
DRYING NORTHEAST TO NORTH BOUNDARY LAYER WINDS FLOW PERSISTS
TONIGHT...LIMITING/PREVENTING ANY LATE NIGHT/EARLY MORNING BR INTO
MON MORNING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
300 AM CDT SUN APR 22 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
300 AM CDT SUN APR 22 2012
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
300 AM CDT SUN APR 22 2012
MAIN FORECAST CONCERNS ARE ON THE NEXT PRECIPITATION CHANCES FOR
TUESDAY NIGHT.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS
SHOWED STRONG RIDGING OVER THE WESTERN U.S. BUILDING INTO SOUTHWEST
CANADA...WHILE TROUGHING WAS PRESENT FROM THE WESTERN GREAT LAKES
REGION SOUTH INTO FLORIDA. MAIN FEATURES OF NOTE TRAVERSING THROUGH
THE TROUGH INCLUDE: AN UPPER LOW NEAR FLORIDA...A POTENT SHORTWAVE
OVER SOUTHWEST IOWA...AND ANOTHER SHORTWAVE IN EASTERN NORTH DAKOTA.
THE POTENT SHORTWAVE HAS BEEN RESPONSIBLE FOR MUCH OF THE
PRECIPITATION AFFECTING THE WESTERN PORTION OF THE FORECAST AREA THE
PAST 18 HOURS...AN IN PARTICULAR A LOW TO MID LEVEL FRONTOGENESIS
ZONE AHEAD OF IT. RUC ANALYSIS SHOWED THIS FRONTOGENESIS HAS DROPPED
SOUTH INTO EASTERN IOWA...AND AS SUCH THE SHOWERS HAVE BEEN
WEAKENING OVER THE FORECAST AREA OVERNIGHT. ANOTHER FEATURE ALLOWING
PRECIPITATION TO WEAKEN IS AN AREA OF HIGH PRESSURE OVER NORTHEAST
ONTARIO. EASTERLY WINDS ARE ADVECTING DRIER AIR OUT OF THE HIGH INTO
THE FORECAST AREA...PARTICULARLY WISCONSIN. 00Z GRB SOUNDING HAD A
PRECIPITABLE WATER OF 0.26 INCHES. THE EASTERLY WINDS STOP AT AN
INVERTED TROUGH WHICH EXTENDS FROM JUST WEST OF MINNEAPOLIS SOUTH
INTO SOUTHEAST IOWA. AIRMASS REMAINS SEASONABLY COOL OVER THE AREA
WITH 850MB TEMPS BETWEEN 0 AND -2C PER 00Z RAOB ANALYSIS.
TODAY THROUGH MONDAY...OVER THE NEXT 24 TO 36 HOURS...A FAIRLY DEEP
TROUGH IS GOING TO FORM OVER THE EASTERN THIRD OF THE U.S....IN
RESPONSE TO THE CURRENT POTENT SHORTWAVE IN IOWA PHASING WITH THE
UPPER LOW IN FLORIDA. IN RESPONSE TO THIS PHASING...A STRONG SPRING
STORM WILL FORM OVER THE NORTHEAST. FOR THE FORECAST AREA...PLAN ON
MAINLY QUIET WEATHER AS HIGH PRESSURE OVER NORTHERN ONTARIO SLOWLY
SINKS SOUTH. THERE ARE STILL SOME ISSUES TO DEAL WITH...THOUGH. THE
FIRST OF WHICH IS THE LINGERING PRECIPITATION AND INVERTED TROUGH.
AS TODAY WEARS ON...THE INVERTED TROUGH SHOULD CONTINUE TO WEAKEN...
ESPECIALLY THIS EVENING WHEN THE SHORTWAVE OVER EASTERN NORTH DAKOTA
SLIDES SOUTH OF THE AREA. ISOLATED/SCATTERED SHOWERS SEEM POSSIBLE
TODAY NEAR THE INVERTED TROUGH...AIDED BY FOCUSED LOW LEVEL
CONVERGENCE AND MOISTURE. MAINTAINED SOME 20 PERCENT CHANCES IN THE
VERY FAR WESTERN PORTION OF THE FORECAST AREA THIS MORNING...IN
AGREEMENT WITH THE 22.00Z NAM/GFS AND LATEST HRRR RUNS. FOR THE REST
OF THE FORECAST AREA TODAY...AN INCREASING NORTHEAST FLOW WILL HELP
BRING IN LOW LEVEL DRY AIR. SOME CLEARING IS POSSIBLE...ESPECIALLY
OVER THE SOUTHEAST END OF THE AREA. TONIGHT...ALTHOUGH THE HIGH
PRESSURE AREA IS MOVING IN...THE NORTHWEST FLOW ALOFT SHOULD HELP
CARRY LOW TO MID LEVEL STRATUS SEEN OVER THE DULUTH AREA SOUTH
ACROSS THE FORECAST AREA. THESE CLOUDS SHOULD BE ENOUGH TO PREVENT
TEMPERATURES FROM REACHING A FROST/FREEZE SITUATION. SKIES ARE
EXPECTED TO CLEAR OUT MONDAY MORNING...THEN ANOTHER SURGE OF MID TO
HIGH CLOUDS ENTER THE PICTURE FROM THE NORTH IN THE AFTERNOON. THIS
IS ASSOCIATED WITH A SMALL PORTION OF THE WESTERN UPPER RIDGE THAT
IS PROGGED TO BUILD TOWARDS THE FORECAST AREA. WE WILL FEEL THIS TOO
BY AN INCREASE IN TEMPERATURES. 850MB TEMPS ARE ONLY 0 TO -2C
TODAY...RESULTING IN HIGHS ONLY IN THE MID 50S. HOWEVER...BY 00Z
TUESDAY...THEY CLIMB TO 2-4C...ALLOWING FOR HIGHS IN THE UPPER 50S
TO LOW 60S.
MONDAY NIGHT THROUGH TUESDAY NIGHT...FOCUS TURNS TO A LOW PRESSURE
SYSTEM PROGGED TO DEVELOP OVER SOUTH CENTRAL SASKATCHEWAN AT 00Z
TUESDAY...ON TOP OF THE UPPER RIDGE. VERY GOOD MODEL AGREEMENT
EXISTS THAT THE UPPER RIDGE WILL FLATTEN AND GET PUSHED SOUTH...IN
RESPONSE TO A SHORTWAVE ROUNDING THE RIDGE WHICH IS LOCATED OFF BAJA
CALIFORNIA RIGHT NOW. AS THE RIDGE FLATTENS...THE LOW PRESSURE
SYSTEM GETS SENT SOUTHEASTWARD INTO WESTERN IOWA BY 12Z WEDNESDAY.
WARM ADVECTION IS FORECAST AHEAD OF THE LOW OVER THE FORECAST AREA
DURING THE ENTIRE MONDAY NIGHT THROUGH TUESDAY NIGHT. 850MB TEMPS
RESPOND BY CLIMBING TO 6 TO 12C BY 00Z WEDNESDAY...WARMEST IN THE
FAR WESTERN PORTION OF THE FORECAST AREA. EVEN MORE WARMING IS
POSSIBLE TUESDAY NIGHT. THE BIGGER QUESTION...THOUGH...IS WHEN/IF
PRECIPITATION WILL OCCUR. PRECIPITABLE WATER VALUES START OFF FAIRLY
LOW AT 00Z TUESDAY...NEAR A 0.5 INCH. GOOD AGREEMENT EXISTS THAT
THESE WILL SLOWLY CLIMB TO NEAR AN INCH BY 00Z WEDNESDAY.
STILL...ISENTROPIC LIFT IS NOT ALL THAT IMPRESSIVE...SUGGESTING MUCH
OF THE WARM ADVECTION IS JUST GOING INTO WARMING. LIKELY TO SEE AN
INCREASE IN MID AND HIGH CLOUDS...THOUGH. THESE CLOUDS WILL HELP TO
KEEP TEMPERATURES UP MONDAY NIGHT. WITH A WARMER START TO
TUESDAY...INCREASING 850MB TEMPS AND FILTERED SUN...ANTICIPATING
HIGHS AT LEAST IN THE 60S AND POSSIBLY LOW 70S IN THE FAR WEST. BY
TUESDAY NIGHT...WITH THE LOW APPROACHING...THERE IS SOME SUGGESTION
OF LOW TO MID LEVEL FRONTOGENESIS INCREASING. THEREFORE...CHANCES OF
PRECIPITATION ARE NECESSARY TUESDAY NIGHT. DO NOT HAVE CONFIDENCE AT
THIS TIME TO GO HIGHER THAN 50 PERCENT AS WOULD LIKE TO SEE STRONGER
FORCING SIGNALS. WILL CONTINUE TO MENTION THUNDER WITH A PLUME OF
500-1000 J/KG OF MUCAPE ADVECTING INTO THE FRONTOGENESIS ZONE.
.LONG TERM...WEDNESDAY THROUGH SATURDAY NIGHT
300 AM CDT SUN APR 22 2012
22.00Z ECMWF/GFS/CANADIAN AND GFS ENSEMBLES ARE IN PRETTY GOOD
AGREEMENT THROUGH THE ENTIRE LONG TERM PERIOD WITH BOTH THE UPPER
LEVEL AND SURFACE PATTERNS. FOR MUCH OF THE LONG TERM PERIOD...THE
FORECAST AREA IS UNDER THE INFLUENCE OF A CANADIAN HIGH PRESSURE
AREA WHICH DROPS DOWN INTO THE WESTERN GREAT LAKES REGION THURSDAY
MORNING. PRIOR TO THEN...THE LOW PRESSURE SYSTEM FROM TUESDAY NIGHT
AND THE FRONTOGENESIS ZONE AHEAD OF IT OVER THE AREA SHOULD REMAIN
MOSTLY IN PLACE ON WEDNESDAY...THEN HEAD OFF TO THE EAST WEDNESDAY
NIGHT. MAINTAINED 20-40 PERCENT CHANCES ON WEDNESDAY...HIGHEST
ALONG/SOUTH OF I-90...THEN JUST A 20 PERCENT CHANCE WEDNESDAY NIGHT
FOR THE DEPARTING PRECIPITATION. DRY AND COOLER CONDITIONS
ANTICIPATED FOR THURSDAY THROUGH FRIDAY WITH THAT CANADIAN HIGH
BUILDING DOWN. WENT TOWARDS THE COLD SIDE OF GUIDANCE FOR LOWS
THURSDAY NIGHT...WHERE FREEZE CONDITIONS SEEM LIKELY ALONG AND
NORTH OF I-94. WILL REALLY HAVE TO WATCH THIS NIGHT TEMPERATURE
WISE...GIVEN DEWPOINTS THAT ARE LIKELY TO DROP INTO THE 20S AND
MAYBE EVEN UPPER TEENS. AN UPPER RIDGE ON THE WEST SIDE OF THE
SURFACE HIGH IS ALSO A FEATURE TO WATCH. RIGHT NOW GOOD AGREEMENT
EXISTS THAT THIS UPPER RIDGE GET PUSHED INTO THE AREA ON SATURDAY
AS TROUGHING DEVELOPS OVER MUCH OF THE WESTERN U.S.. WILL SEE IF
THAT PROGRESSION STAYS...BUT WITH THAT RIDGE MOVING IN MEANS WARM
ADVECTION...AND THEREFORE CHANCES OF SHOWERS AND THUNDERSTORMS
ENTER THE PICTURE. SEEMS LIKE THE BETTER CHANCES FOR RAIN WOULD
COME SATURDAY NIGHT AND SUNDAY AS SHORTWAVES EJECT OUT OF THE
WESTERN TROUGH AND MOVE INTO THE AREA.
&&
.AVIATION...
1000 PM CDT SAT APR 21 2012
LOW CONFIDENCE WITH RELATION TO CIGS AS A COMPLEX SCENARIO MAKES
REFINING THE FORECAST DIFFICULT.
SOME CLARITY THOUGH WITH THE LATEST RUC13 AND 00Z NAM12 KEEPING ANY
DEEPER SATURATION...AND MVFR CIGS...WEST OF KLSE. HOWEVER...BOTH
SUGGEST THAT THE TRACK OF THE SOUTHEAST DEPARTING LOW WILL PLACE
KRST ON THE EASTERN FRINGE OF MVFR CIGS OVERNIGHT. WILL ADD SOME
MENTION FOR KRST.
IN ADDITION TO THE CLOUDS...AN INVERTED SFC TROUGH HANGING NORTH OF
THE LOW WILL BE THE FOCUS FOR SCT -SHRA OVERNIGHT. PROBABLY LIGHT
ENOUGH WHERE VSBYS ARE NOT IMPACTED...WITH MINIMAL ACCUMULATIONS.
THE TROUGH COULD REMAIN A FOCUS FOR SOME -SHRA DEVELOPMENT ON
SUNDAY...BUT ALL MESO MODELS ARE SOUR ON THIS POTENTIAL. DEEP
SATURATION REMAINS AROUND THIS FEATURE...BUT A FETCH OF DRIER MID
LEVEL AIR WILL WORK WEST INTO THE MISSISSIPPI RIVER...HELPING TO
CLEAR AT LEAST SOME OF THE LOW CLOUDS OUT.
LOOK FOR WINDS TO TURN SOUTHEAST THIS EVENING...SWINGING TO THE
NORTH BY 00Z MON. HIGH PRESSURE BUILDS ACROSS THE UPPER MISSISSIPPI
RIVER VALLEY LATE MONDAY...AND SHOULD HELP CLEAR MORE OF THE
MOISTURE/CLOUDS OUT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
300 AM CDT SUN APR 22 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1241 AM EDT TUE APR 24 2012
.SYNOPSIS...
ISSUED AT 414 PM EDT MON APR 23 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A HIGH AMPLITUDE PATTERN WITH
A MID/UPPER LEVEL RIDGE OVER THE WRN CONUS AND A TROUGH OVER THE
EAST RESULTING IN CONFLUENT NRLY FLOW THROUGH THE UPPER GREAT LAKES.
AN UPSTREAM SHORTWAVE TROUGH MOVING INTO NRN MANITOBA SUPPORTED AN
EXTENSIVE AREA OF CLOUDS AND A FEW LIGHT SHOWERS. AT THE SFC...THE
GRADIENT WAS INCREASING BTWN LOW PRESSURE OVER ERN NY AND A RIDGE
OVER THE UPPER MS VALLEY.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 414 PM EDT MON APR 23 2012
AS THE SHORTWAVE TROUGH MOVES TOWARD THE AREA...EXPECT MID CLOUDS TO
INCREASE LATE TONIGHT. THE GFS WAS MORE AGGRESSIVE WITH 290K
ISENTROPIC LIFT AND PCPN POTENTIAL COMPARED TO THE REST OF THE
MODELS. SO...GIVEN THE LACK OF MOISTURE AVBL AND THE RELATIVELY
MODEST DYNAMICS...ONLY SLIGHT CHANCE POPS WERE INCLUDED OVER WEST.
SOME INLAND TEMPS MAY FALL TO NEAR FREEZING BUT SOUNDINGS SUGGEST
THAT PCPN TYPE WOULD BE RAIN.
RELATIVELY POOR RH RECOVERY IS EXPECTED OVERNIGHT ACROSS THE
AREA...BUT MOST SIGNIFICANTLY OVER THE EASTERN HALF. EVEN WITH THE
LOSS OF DAYTIME HEATING/MIXING 9250 MB WINDS IN THE 40 TO 45 KT
RANGE...FROM 03Z TO 15Z TUESDAY. AFTER AREAS OF CLOUDS WITH THE
SHRTWV MOVE OUT BY AFTERNOON...SUNSHINE AND MIXING SHOULD AGAIN DROP
DEWPOINTS BLO GUIDANCE TO AROUND 20F. WITH TEMPERATURES INTO THE MID
AND UPPER 50S...RH VALUES NEAR 25 PCT WILL AGAIN LEAD TO ELEVATED WILD
FIRE RISK.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 414 PM EDT MON APR 23 2012
LOW PRESSURE SYSTEM CURRENTLY OVER NEW YORK WILL BE LOCATED OVER
WRN QUEBEC AT THE START OF THE PERIOD AND WILL PUSH N AND WEAKEN
WHILE THE UPPER RIDGE THAT HAS BEEN OVER THE WRN CONUS APPROACHES
THE WRN GREAT LKS. WEAK SHORTWAVE MOVING THROUGH THE NW FLOW ALOFT
ON TUES NIGHT INTO WED...WHILE ASSOCIATED SFC LOW SLIDES FROM THE
DAKOTAS TOWARDS THE LOWER GREAT LAKES. BROAD H850-500 WAA...Q-VECTOR
CONV...AND MOISTURE PUSHING IN SLOWLY TUES EVENING AND CONTINUES
THROUGH WED. ECMWF FARTHEST SW WITH THE BEST WAA...WHILE NAM/GFS/GEM
ALL TRY TO FOCUS A STRONGER AREA OF WAA OVER THE NRN CWA ON WED.
THESE DIFFERENCES LEAD TO SOME UNCERTAINTY ON THE EXACT LOCATION OF
THE RAIN. IN ADDITION...DRY AIR BELOW H800 WILL TRY TO LIMIT PCPN
CHANCES THROUGH MUCH OF THE OVERNIGHT HOURS OVER THE FAR WRN CWA.
ATMO DOESN/T REALLY SEEM TO MOISTEN UP UNTIL DAYLIGHT HOURS ON WED.
THIS DELAYED MOISTENING WILL LIMIT PCPN ACROSS THE REST OF THE CWA
FOR THE FIRST PART OF WED. HAVE TRIED TO PUT SOME TIMING IN FOR THIS
DRY AIR HOLDING OFF PCPN. EVEN WITH THE DRY AIR...SEEM TO HAVE
ENOUGH SIGNALS TO BUMP CHANCE POPS UP A LITTLE MORE...ESPECIALLY
OVER THE WRN CWA DURING THE DAY WED. THE INITIAL DRY AIR AND
POSITIONING OF THE PCPN PROVIDES A LITTLE TOO MUCH UNCERTAINTY TO
BUMP THEM UP TO LIKELY VALES.
MUCH STRONGER WAVE AND ASSOCIATED HEIGHT FALLS ARRIVES LATE WED
NIGHT AND THURS MORNING...WHICH BRING THE MUCH COOLER H850 TEMPS TO
THE AREA. THE COLD AIR ON THE BACK SIDE OF THE SYSTEM COULD LEAD TO
LK ENHANCED CLOUDS/PCPN LINGERING BEHIND THE WAVE INTO THURS
MORNING. NAM HOLDING ON TO THE LLVL MOISTURE THROUGH THE MORNING
HOURS BEFORE THE DRIER AIR AND SUBSIDENCE FROM THE HIGH PRESSURE
RIDGE START TO TAKE OVER. WITH THE NRLY FLOW OVER THE AREA DURING
THE MORNING...COMBINING WITH A BRIEF OVERLAP OF THE H850 TEMPS TO
-8C AND MOISTURE...THINK THERE WILL BE A BRIEF PERIOD OF STRONGER
RAIN/SNOW SHOWERS OVER THE NCNTRL UPSLOPE LOCATIONS MAINLY FROM
06-15Z. MAIN CONCERN WITH SNOW IS THAT THE LLVL TEMPS MIGHT NOT GET
COLD ENOUGH TO SUPPORT SNOW UNTIL THE BEST MOISTURE DEPARTS.
THUS...DELAYED THE SNOW CHANGE OVER TO OCCUR LATER IN THE NIGHT AND
DURING THE FIRST PART OF THURS MORNING. SNOW WILL OCCUR A LITTLE
EARLY OVER THE NW HALF OF THE CWA...BUT BOTH CASES WILL NEED A
LITTLE WHILE TO COOL CLOUD TEMPS AND GET ICE CRYSTALS BACK IN THE
CLOUD DUE TO THE DRY H750 AIR ARRIVING WED EVENING.
WITH THE HIGH PRESSURE RIDGE QUICKLY MOVING IN ON THURS AND LLVL
MOISTURE DEPARTING FOR ALL BUT FAR ERN UPPER MI...WILL DECREASE THE
CLOUDS ACROSS THE AREA EVEN THOUGH H850 TEMPS ARE STILL AROUND -6
OR -7C. COULD BE A LITTLE GUSTY WITH THE STRONG PRESSURE GRADIENT
LATE WED NIGHT INTO THURS. WITH THE COLD AIR ARRIVING AND H925
WINDS TO 30KTS...SHOULD SEE GUSTS IN THE 30-35MPH RANGE NEAR LK
SUPERIOR IN THE MORNING AND THEN DIMINISHING FORM WEST TO EAST
THROUGH THE DAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1241 AM EDT TUE APR 24 2012
VFR CONDITIONS SHOULD REMAIN THROUGH THE NEXT 24 HOURS AT ALL SITES.
A WEATHER SYSTEM APPROACHING ON WED WILL BRING SOME MID CLOUDS INTO
THE AREA TUE NIGHT. GUSTY WINDS OFF THE SFC AT KSAW WILL CAUSE LLWS
OVERNIGHT.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 414 PM EDT MON APR 23 2012
A STRONG LOW PRESSURE SYSTEM WILL MOVE NNE INTO THE ERN GREAT LAKES
BY THIS EVENING. THIS HAS RESULTED IN INCREASING NNW WINDS...UP TO
30KTS OVER ERN LK SUPERIOR WHICH WILL CONTINUE INTO TUESDAY MORNING.
A LOW PRESSURE SYSTEM WILL MOVE ACROSS THE UPPER LAKES ON WED WHILE
BEFORE STRONG HIGH PRESSURE BUILDS FROM CENTRAL CANADA INTO THE
GREAT LAKES WEDNESDAY NIGHT INTO THURSDAY. THE STRONG GRADIENT
BETWEEN THESE SYSTEMS WILL LEAD TO NORTHERLY GUSTS UP TO 30KTS
OVER CENTRAL AND EASTERN LAKE SUPERIOR WEDNESDAY NIGHT INTO THURSDAY
MORNING. A FEW GALE FORCE GUSTS TO 35KTS ARE ALSO POSSIBLE DURING
THIS TIME.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
EXTENDED...JMW
AVIATION...07
MARINE...JLB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
421 AM CDT TUE APR 24 2012
.DISCUSSION...
STRONG MID LEVEL TEMPERATURE GRADIENT ACROSS THE AREA THIS MORNING
BETWEEN ERN TROUGH AND WRN RIDGE HAS RESULTED IN A NICE BAND OF
WAA/ISENTROPICALLY INDUCED MID LEVEL CLOUD COVER ACROSS ERN HALF OF
THE MPX AREA. LAPS SOUNDINGS ACROSS THE AREA SHOW AIR BELOW H7 IS
QUITE DRY...WHICH IS REFLECTED IN CLOUD HEIGHT AOA 8K FT.
STILL...A FEW 50 DBZ PIXELS IN SHOWERS FROM TIME TO TIME IS AN
INDICATION THAT ENOUGH PRECIP IS BEING GENERATED TO GET SOME
BRIEF SHOWERS TO THE GROUND. HRRR REFLECTIVITY FORECASTS HANDLING
THESE SHOWERS WELL THIS MORNING...AND HAS MOST OF THEM GONE BY 12Z
AS AREA OF ISENTROPIC LIFT PUSHES SOUTH...SO LEFT NOTHING MORE
THAN A SPRINKLE MENTION ACROSS ERN MN THROUGH 15Z. FOR THE REST OF
TODAY...THERMAL GRADIENT AND UPPER JET CONFIGURATION WILL REMAIN
IN PLACE...WHICH MAY RESULT IN CLOUDS REMAINING ACROSS WRN WI MUCH OF
THE DAY. FOR HIGHS...SEEING A STRONG PUSH OF WARM AIR AT H85...BUT
WITH THE DEEP AND COLD TROUGH TO THE EAST...DOES LOOK LIKE WARMER
AIR DOES GET SLOWED UP SOME...WITH HIGHS IN WI LIKELY ONLY GETTING
TO AROUND 60...EVEN IF THE CLOUDS CAN CLEAR OUT THIS AFTERNOON.
OUT IN WRN MN...SHOULD SEE MORE WIDESPREAD 70S TODAY...BUT NOT
EXPECTING ANY 80 DEGREE READINGS. THE +20C ISOTHERM AT H85 WAS A
FAIRLY GOOD DEMARCATION FOR WHERE 80 DEGREE HIGHS WERE OBSERVED
YESTERDAY...AND ALL MODELS KEEP THAT WEST OF MN TODAY.
FOR TONIGHT AND WEDNESDAY...MODELS CONTINUE TO ADVERTISE THE WRN
RIDGE FLATTENING OUT SOME...WITH SHORTWAVE ENERGY AND ASSOCIATED
THUNDERSTORMS CURRENTLY NEAR THE IDAHO CHIMNEY DRIVING A SFC LOW
ACROSS MN. STILL EXPECTING A STRONG WAA PUSH ALONG AND NORTH OF
THE LOW TRACK...WHICH THE SREF/ECMWF CONTINUING TO BRING BASICALLY
STRAIGHT DOWN I-94...WITH BEST RAINFALL CHANCES ALONG AND NORTH OF
THE 94 CORRIDOR AS A RESULT. BEST RAIN CHANCES LOOK TO COME IN
AFTER MIDNIGHT...WITH ELEVATED INSTABILITY STILL LOOKING TO BE MORE
THAN SUFFICIENT TO CONTINUE THE MENTION OF THUNDER. FOR
WEDNESDAY...TO SAY THE FORECAST IS COMPLEX IS AN UNDERSTATEMENT.
BY THE AFTERNOON...SFC LOW LOOKS TO BE IN THE RED WING/LA CROSSE
AREA AS A POLAR FRONT COMES SURGING SOUTH OUT OF CANADA. ANY
PRECIP LOOKS TO CONTINUE TO BE ASSOCIATED WITH THE SFC LOW...BUT
WITH THE FRONT COMING SOUTH IN THE AFTERNOON...DOES LOOK LIKE A
LOW/TRIPLE POINT WILL BE SETTING UP OVER SE MN. WITH TEMPS WELL
INTO THE 70S AND SFC DEWPS IN THE MID 50S AND BULK SHEAR UP AROUND
50 KTS...A SEVERE THREAT WOULD EXIST FOR ANY SFC BASED CONVECTION
THAT CAN TAKE HOLD IN THE AFTERNOON. AT THIS POINT...THE BEST
THREAT OF SEVERE WEATHER LOOKS TO BE JUST SE OF THE AREA...BUT SPC
SREF CONDITIONAL SEVERE WEATHER PROBS FOR WEDNESDAY AFTERNOON DO
SPIKE UP IN SE MN...WITH THE DAY2 OUTLOOK BRINGING MARGINAL SEVERE
UP INTO THE SE MPX CWA. BESIDE THE THUNDER THREAT...THE
TEMPERATURE FORECAST WAS QUITE THE HEADACHE AS WELL. THE 00Z ECMWF
HAS HIGHS UP AROUND 80 FROM RWF DOWN TO FAIRMONT...WITH THE
LADYSMITH AREA ONLY GETTING TO 50. WINDS AHEAD OF THE POLAR FRONT
LOOK TO COME OUT OF THE WSW...SO DOES LOOK LIKE SWRN AREA COULD
REALLY WARM UP QUITE A BIT WEDNESDAY...WHILE MOST MODELS SHOW
SHOWERS/STATUS HANGING ON MOST OF THE DAY ACROSS WI...WITH
TEMPERATURES STRUGGLING TO BUDGE THERE.
THE POLAR FRONT LOOKS DRIVE ANY PRECIP SOUTH AND EAST OF THE AREA
WEDNESDAY NIGHT. AN UPPER 1030S HIGH OVER HUDSON BAY WILL BE
FILTERING MUCH COLDER AND DRIER AIR INTO THE AREA ON
THURSDAY....WITH HIGHS ACROSS WRN/SRN MN RUNNING AS MUCH AS 20
DEGREES COLDER ON THURSDAY THAN ON WEDNESDAY. IT IS THE HIGH AND
ASSOCIATED DRY AIR THAT WILL PLAY A LARGE ROLE IN NRN EXTENT OF
PRECIP FRIDAY INTO SATURDAY. THE 00Z GEM/ECMWF BASICALLY KEEP ALL
BUT THE I-90 CORRIDOR DRY DURING THIS PERIOD...WITH THE ECMWF
DROPPING DEWPS DOWN INTO THE TEENS AND 20S BY FRIDAY MORNING ACROSS
THE AREA. EVEN THE GFS HAS PULLED PRECIP FURTHER SOUTH...WITH THE
NE CWA LOOKING TO REMAIN DRY WITH THIS SYSTEM. GIVEN THE STRENGTH
OF THE HUDSON HIGH...AND THE REX BLOCK PROGGED TO BE OVER SRN
CANADA BY THE END OF THE WEEK...LIKE THE IDEA OF IT BEING
DIFFICULT FOR PRECIP TO MAKE IT MUCH FURTHER NORTH THAN THE MN
RIVER...SIMILAR TO WHAT WE SAW WITH THE SYSTEM THAT IMPACTED
SOUTHERN MN WED NIGHT/THU OF LAST WEEK. WHERE EVER THE RAIN DOES
END UP THOUGH...IT DOES LOOK TO BE RATHER RAW...WITH TEMPS LIKELY
STRUGGLING INTO THE LOWER 40S.
&&
.AVIATION.../06Z TAF ISSUANCE/
SURFACE HIGH PRESSURE RIDGE...MOVING EAST OVER THE NEXT 12 HOURS.
SOME MID/HIGH CLOUDS ASSOCIATED WITH A WEAK WARM AIR
ADVECTION...OCCURRING OVER THE UPPER MIDWEST...WILL CONTINUE TO
DEVELOP OVER THE FORECAST AREA OVERNIGHT. CLOUDS WILL CONTINUE TO
INCREASE AHEAD OF AN APPROACHING LOW PRESSURE SYSTEM. A WRM FNT WILL
LIFT NORTHEAST FROM THE DAKOTAS TUESDAY AFTERNOON. AS MENTION
BEFORE...SFC WINDS WILL BE THE TRICKY PART IN THIS TAF
PERIOD...MAINLY DIRECTIONS. MITIGATING THESE CONCERNS IS THAT SPEEDS
WILL BE LESS THAN 10 KT THROUGH THE PERIOD. OVERALL...VFR CONDITIONS
PREVAIL.
MSP...NO PROBLEMS OR CONCERN DURING THE TAF PERIOD. VFR CONDITIONS
WILL PREVAIL THROUGH TUESDAY EVENING. CONDITIONS POSSIBLY LOWERING
TO MVFR IN SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS LATE TUESDAY
NIGHT INTO WEDNESDAY MORNING. WINDS LIGHT AND VARIABLE OVERNIGHT
THEN BECOMING SOUTHEAST 5 TO 10 KNOTS BY TUESDAY EVENING.
//OUTLOOK...TUESDAY NIGHT THROUGH SUNDAY...
.TUE NIGHT AND WED...CHANCE OF -SHRA/-TSRA LATE TUESDAY NIGHT INTO
WEDNESDAY WITH MVFR CIGS/VSBY POSSIBLE.
.WED NIGHT AND THU...VFR UNDER HIGH PRESSURE.
.THU NIGHT THRU SUN...CHC OF -SHRA THROUGHOUT THE PERIOD AS SEVERAL
WAVES OF LOW PRESSURE MOVE THRU THE AREA. OCNL MVFR-IFR CONDITIONS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
MPG/JVM
AREA FORECAST DISCUSSION
NWS RALEIGH NC
135 AM EDT TUE APR 24 2012
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL DIVE SOUTHEASTWARD ACROSS OUR REGION
THIS AFTERNOON AND EVENING. WEAK HIGH PRESSURE WILL FOLLOW FOR LATER
TONIGHT THROUGH WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 10 PM MONDAY...
DEEP LOW PRESSURE OVER THE NORTHEAST US IS EXPECTED TO BECOME
VERTICALLY STACKED BY DAYBREAK.
SCATTERED SHOWERS SEEN EARLIER THIS EVENING HAVE LONG ENDED AND
SOME BREAKS HAVE STARTED TO DEVELOP IN THE RATHER EXTENSIVE CLOUD
SHIELD AS CENTRAL NC WILL SEE A PERIOD OF SUBSIDENCE OVERNIGHT
BETWEEN THE NEXT SUBSTANTIAL VORT MAX PIVOTS ACROSS THE AREA. THIS
SHOULD RESULT IN A CONTINUED DECREASE IN CLOUDS WITH MOSTLY CLEAR
SKIES EXPECTED BY DAYBREAK.
WINDS APPEAR AS IF THEY WILL REMAIN UP OVERNIGHT WITH LATEST SFC
ANALYSIS AND RUC FORECAST MSL PRESSURE CONTINUING TO DEPICT
A GOOD 4 TO 5 MB PRESSURE GRADIENT OVER THE AREA TONIGHT...WHICH
SHOULD KEEP WINDS STIRRING BETWEEN 4 TO 6 KTS. THIS MIXING COUPLED
WITH GRADUAL CLEARING SHOULD RESULT IN A SLOW TEMPERATURE FALL
OVERNIGHT WITH TEMPERATURES MOSTLY IN THE UPPER 30S TO LOWER 40S. A
FEW OUTLYING/SHELTERED AREAS COULD FALL INTO THE MID 30S(34-35)FOR A
BRIEF...ONE TO TWO HOUR WINDOW JUST BEFORE DAYBREAK...WHICH
COULD RESULT IN SOME VERY PATCHY FROST AT BEST. GIVEN THE
UNFAVORABLE CONDITIONS AND THE EXPECTED LIMITED NATURE IN FROST
DEVELOPMENT...WILL CONTINUE TO MENTION PATCHY FROST IN HWO
ONLY...WITH NO PLANS ON ISSUING AN ADVISORY.
&&
.SHORT TERM /TUESDAY AND TUESDAY NIGHT/...
AS OF 310 PM MONDAY...
ANOTHER VORT MAXIMUM IN NW FLOW BEHIND DEPARTING UPPER LEVEL LOW
WILL APPROACH OUR REGION TUESDAY MORNING AND AFFECT OUR AREA TUESDAY
AFTERNOON-EVENING. MODEL GUIDANCE HAS COME INTO BETTER CONSENSUS AS
FAR AS PATH AND TIMING. ASSOCIATED MID LEVEL COOL POOL WITH THIS
FEATURE WILL YIELD MID LEVEL LAPSE RATES 7-8 DEGREE C/KM. IF SHOWERS
OBTAIN SUFFICIENT DEPTH...MAY SEE A FEW LIGHTNING STRIKES AND SMALL
HAIL WITH THE STRONGER CORES. ALSO INVERTED VEE SOUNDINGS SUGGEST
POTENTIAL FOR GUSTY WINDS...THOUGH WIND PROFILE THROUGH THE COLUMN
(BELOW 12K FT) AOB 25KTS. THUS GUSTS SHOULD BE BELOW SEVERE CRITERIA.
SHOULD SEE DECENT DISPLAY OF SUN THROUGH THE THE MORNING AND
POSSIBLY EARLY AFTERNOON HOURS BEFORE CLOUDS INCREASE THICKEN.
THICKNESSES TUESDAY RECOVER ABOUT 15M FROM TODAY`S UNSEASONABLY LOW
VALUES (ABOUT 40M BELOW NORMAL). STILL...MAX TEMPS WILL AVERAGE 10
DEGREES BE NORMAL IN THE MID-UPPER 60S. IF CLOUDS DEVELOP SOONER
THAN EXPECTED....MAX TEMPS MAY END UP BEING 3-4 DEGREES
COOLER...ESPECIALLY SW HALF.
ANOTHER BREEZY DAY EXPECTED TUESDAY DUE TO DEEP LOW OVER THE
EASTERN LAKES/SOUTHERN NEW ENGLAND AND HIGH PRESSURE OVER THE LOWER
MS VALLEY. EXPECT WLY WINDS 10-15 MPH WITH GUSTS AROUND 25 MPH.
WINDS WILL SUBSIDE A BIT IN THE AFTERNOON AS CLOUD COVERAGE
INCREASES/THICKENS.
TUESDAY NIGHT...VORT MAX WILL SLIDE JUST SW OF OUR REGION IN THE
EVENING...ITS INFLUENCE WANING BY MIDNIGHT. THIS SHOULD LEAD TO
DECREASING CLOUD COVERAGE. MIN TEMPS UPPER 30S NE TO THE LOW-MID
40S WEST AND SOUTH.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
AS OF 300 PM MONDAY...
WITH SURFACE HIGH PRESSURE CENTERED OVER FL 12Z WEDNESDAY AND
RIDGING INTO NC...EXPECT WEDNESDAY TO REMAIN DRY FOR THE MOST PART
WITH SOME SHOWERS APPROACHING FROM THE WEST WEDNESDAY AND INTO
WEDNESDAY NIGHT. HIGH TEMPS WEDNESDAY RANGING FROM THE UPPER 60S N
TO MID 70S SW.
MODEL SOLUTIONS ARE STILL NOT IN VERY GOOD AGREEMENT WITH THE
POTENTIAL SHORT WAVES IMPACTING NC OVER THE REMAINDER OF THE
FORECAST PERIOD. THAT BEING SAID...BOTH THE GFS AND ECMWF INDICATE
THE SHORT WAVE MOVING OVER NC THURSDAY NIGHT SO THERE IS CONFIDENCE
THAT AT LEAST THE NORTHERN HALF OF THE AREA WILL GET SOME PRECIP.
HAVE CONTINUED CHANCE POPS THURSDAY AFTERNOON AND THURSDAY NIGHT
WITH THE CHANCE FOR SOME ISOLATED THUNDER THURSDAY EVENING. LOWS
WEDNESDAY NIGHT AND THURSDAY NIGHT IN THE MID TO UPPER 50S...WITH
HIGHS THURSDAY IN THE UPPER 70S NORTH TO LOW 80S SOUTH. EXPECT WINDS
TO BE 10-15 KTS THURSDAY AFTERNOON.
AS STATED IN THE PREVIOUS DISCUSSION...FRIDAYS FORECAST WILL BE
DETERMINED BY HOW FAR SOUTH THE EAST WEST FRONT TRAILING AN OFFSHORE
SURFACE LOW WILL PUSH... AND IF HIGH PRESSURE WILL BE ABLE TO SPILL
OVER THE MID ATLANTIC MOUNTAINS AND SOUTH... OR REMAIN MORE CONFINED
WEST OF THE APPALACHIANS. ALTHOUGH CONFIDENCE IS NOT HIGH...HAVE
LEANED MORE TOWARD THE GFS SOLUTIONS FOR FRIDAY AND FRIDAY NIGHT
WHICH DEPICT A SFC LOW DEVELOPING OVER NC FRIDAY NIGHT. AS
SUCH...HAVE LEFT THE CHANCE FOR PRECIP ACROSS THE NE WITH SLIGHT
CHANCE ELSEWHERE. HIGHS FRIDAY IN THE LOW TO MID 70S AND LOWS IN THE
UPPER 40S TO MID 50S...HOWEVER THIS IS DEPENDENT ON WHETHER OR NOT
PRECIP DOES IN FACT DEVELOP AND ARE SUBJECT TO CHANGE.
HIGH PRESSURE SHOULD BUILD IN FOR SATURDAY AND SUNDAY BEFORE THE
NEXT SYSTEM APPROACHES FROM THE NW SUNDAY NIGHT. HAVE KEPT THE
FORECAST DRY THROUGH MONDAY. GIVEN THE DIFFERENCES IN MODEL
SOLUTIONS REGARDING THE TIMING OF THE NEXT SYSTEM PRECIP IS POSSIBLE
SUNDAY NIGHT INTO MONDAY...HOWEVER CONFIDENCE IS TOO LOW ON WHEN IT
WILL OCCUR THAT HAVE LEFT POPS JUST UNDER SLIGHT CHANCE. HIGHS
SATURDAY IN THE UPPER 60S TO MID 70S NE TO SW. WARMER SUNDAY AND
MONDAY WITH HIGHS IN THE 70S. LOWS SATURDAY AND SUNDAY NIGHT NEAR 50
NORTH AND MID 50S SOUTH.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 135 AM TUESDAY...
CLEARING SKIES AND LIGHT SOUTHWEST WINDS WILL RULE THROUGH
12-14Z...BEFORE RESIDUALLY STRONG CYCLONIC FLOW AROUND AN OCCLUDING
LOW PRESSURE SYSTEM NEAR LAKE ERIE MIXES THROUGH THE BOUNDARY LAYER
WITH DAYTIME HEATING AND YIELDS STRONG WESTERLY SURFACE WINDS --
SUSTAINED 15-20 KTS WITH GUSTS OF 20-25 KTS -- FOR THE REMAINDER OF
THE DAY. INITIALLY CLEAR SKIES WILL FILL WITH BROKEN HIGH-BASED
CUMULUS BETWEEN 7-8 THOUSAND FEET DURING THE AFTERNOON OWING TO THE
APPROACH OF A COMPACT MID-UPPER LEVEL DISTURBANCE IN NORTHWESTERLY
FLOW ALOFT; AND SOME OF THESE CUMULUS WILL DEEPEN SUFFICIENTLY TO
PRODUCE WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WITH
GUSTY SURFACE WINDS OF UP TO 40-45 KTS BETWEEN 22Z-05Z. HAVE
ACCORDINGLY INCLUDED VICINITY SHOWERS IN ALL TAFS TO ACCOUNT FOR
THIS PROBABILITY. SURFACE WINDS WILL DIMINISH WITH LOSS OF HEATING
AND RESULTANT BOUNDARY LAYER MIXING DURING THE EVENING...WITH JUST
SCATTERED MID-HIGH LEVEL CLOUDS AT WORST EXPECTED FOR THE REMAINDER
OF THE NIGHT.
OUTLOOK: BRIEF EPISODES OF SHOWERS AND STORMS AND SUB-VFR CONDITIONS
WILL BE POSSIBLE OWING TO THE PASSAGE OF A FEW FAST-MOVING LOW
PRESSURE SYSTEMS FROM LATE WED NIGHT THROUGH THE WEEKEND...BUT
GENERALLY VFR CONDITIONS ARE OTHERWISE EXPECTED.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MWS
NEAR TERM...CBL/WSS
SHORT TERM...WSS
LONG TERM...KC
AVIATION...MWS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
132 AM EDT TUE APR 24 2012
.SYNOPSIS...
DEEP LOW PRESSURE OVER EASTERN NEW YORK WILL MOVE TO NORTH OF LAKE
ONTARIO TONIGHT. THE LOW WILL WEAKEN AS IT MOVES NORTHEAST
TUESDAY AND TUESDAY NIGHT. A WEAK RIDGE OF HIGH PRESSURE WILL
BUILD NORTHEAST ACROSS THE LOCAL AREA TUESDAY AFTERNOON THROUGH
WEDNESDAY. WEAK LOW PRESSURE WILL MOVE EAST ACROSS THE CENTRAL
GREAT LAKES FORCING A COLD FRONT THROUGH THE AREA THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
TOUGH OVERNIGHT FORECAST FOR THE LAKESHORE OF NW PA. ON THE EDGE
ABOUT WHETHER A WARNING OR ADVISORY IS NEEDED. ANOTHER SURGE OF
MOISTURE AND OMEGA IS EXPECTED OVERNIGHT AND THE NORTHWEST WINDS
WILL BECOME MORE WEST NORTHWEST. THIS MAY BRING IN SOME BANDS OF
LAKE EFFECT SNOW INTO THE LAKESHORE COUNTIES. WITH THE WIND AND
THE SNOW BEING WET...THIS COULD CAUSE SOME PROBLEMS. LEFT THE
WARNING GOING...BUT THE BEST CHANCE FOR SIGNIFICANT SNOWFALL WILL
BE FROM INTERSTATE 90 AND SOUTH.
OVER NORTHWEST OHIO SOME CLOUDS AND SOME WIND WILL OCCUR. EVEN
THOUGH THE WINDS HAVE DECREASED AFTER SUNSET...THEY SHOULD
INCREASE AGAIN...JUST ENOUGH TO KEEP THE LOWS FROM GETTING TOO
COLD AND EXTENSIVE FROST. THUS NO HEADLINES FOR THAT AREA.
ELSEWHERE OVER NORTHEAST OHIO...INCREASING CLOUDS. THE
PRECIPITATION MAY NOT GET TOO FAR WEST OF ASHTABULA COUNTY. GOING
WITH THE HRRR MODEL ON THIS...LOWERED THE POPS OVER PARTS OF
NORTHEAST OHIO. MADE SOME ADJUSTMENTS TO THE LOWS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY NIGHT/...
WARM AIR ADVECTION BEGINS TOMORROW AS THE SURFACE LOW BEGINS TO
LIFT NE. IT SHOULD BECOME WARM ENOUGH FOR ALL RAIN BY MIDDAY
TUESDAY. HAVE SHORTENED THE WARNING BY A FEW HOURS. WESTERN AREAS
SHOULD SEE A FAIR AMOUNT OF SUNSHINE. WEAK HIGH PRESSURE WILL
BEGIN TO BUILD IN LATE TOMORROW AND THIS SHOULD END ANY LINGERING
PRECIP TO THE EAST OF CLEVELAND TOMORROW EVENING. HIGH PRESSURE
WILL REMAIN IN CONTROL WEDNESDAY. MODELS STILL SHOWING ANOTHER
SYSTEM DIVING SE ACROSS THE REGION ON THURSDAY. HAVE ADJUSTED POPS
SLIGHTLY. SUSPECT THAT WE WILL NEED LIKELY POPS FOR A PERIOD OR
TWO. RIGHT NOW IT APPEARS BEST CHANCES FOR PRECIP WILL BE LATE
WEDNESDAY NIGHT AND THURSDAY MORNING. A COLD FRONT WILL MOVE SE
ACROSS THE REGION DURING THE DAY AND WILL TRY TO DRY THINGS OUT
THURSDAY NIGHT. HAVE TRENDED SLIGHTLY COOLER THAN GUIDANCE THE
NEXT COUPLE OF DAYS...ESPECIALLY IN NW PA WHERE THERE WILL BE SOME
SNOW COVER.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
LITTLE CHANGE FOR THE EXTENDED PERIOD. GFS CONTINUES TO MOVE LOW
PRESSURE ACROSS THE OHIO VALLEY/LOWER GREAT LAKES WITH RAIN
DEVELOPING ACROSS AREA ON SATURDAY. ECMWF ON THE OTHER HAND
CONTINUES TO BE FURTHER NORTH WITH THE LOW AND 6-12 HOURS SLOWER
WITH THE RAIN. SINCE LOW CONFIDENCE CONTINUED WITH CHANCE POPS
SATURDAY INTO SUNDAY. KEPT MONDAY DRY AND A LITTLE WARMER AS HIGH
PRESSURE BUILDS OVER THE AREA.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
SURFACE LOW OVER SOUTHEAST ONTARIO WILL MOVE NORTH TO QUEBEC
TODAY. MOISTURE CONTINUES TO ROTATE AROUND THE LOW AND INTO
NORTHEAST OHIO AND NORTHWEST PA ALTHOUGH MOST PRECIP HAS BEEN OVER
NWRN PA. MODELS SHOW MOISTURE ROTATING BACK WEST INTO NERN OHIO
AFTER 15Z AS A SHORT WAVE DROPS ACROSS THE AREA. A VERY LEAST
WOULD EXPECT A LOWER OR MID DECK CIG TO GET BACK INTO KCLE AND
KCAK FOR THE LATE MORNING AND EARLY AFTERNOON. COULD ALSO SEE A
FEW SNOW SHOWERS BUT AT PRESENT DO NOT EXPECT MORE THAN A FLURRY.
KYNG BROUGHT IN AN MVFR CIGS WITH MVFR SNOW SHOWERS AS LOWER LEVEL
MOISTURE SEEMS TO GET INTO THE AREA. KERI SHOULD CONTINUE TO BE IN
AND OUT OF RAIN/SNOW SHOWERS AND THEREFORE IN AND OUT OF MVFR
CONDITIONS THROUGH MUCH OF THE PERIOD.
WINDS WILL AGAIN BECOME GUSTY FROM THE NORTHWEST DURING THE LATE
MORNING AND AFTERNOON HOURS. TOOK WINDS TO ABOUT 20 KNOTS WITH
GUSTS AROUND 30.
.OUTLOOK...NON VFR LIKELY AGAIN WEDNESDAY NIGHT AND THURSDAY. NON
VFR RETURNING ON SATURDAY.
&&
.MARINE...
LOW PRESSURE OVER EASTERN NEW YORK WILL LINGER OVER NEW YORK STATE
TONIGHT AND THEN GRADUALLY MOVE NORTH INTO ONTARIO AND QUEBEC ON
TUESDAY. THE GALE WARNING HAS BEEN CANCELLED FOR AREAS WEST OF
VERMILLION AS WINDS HAVE DROPPED TO 15 TO 20 KNOTS. SOME INCREASE
IN WINDS IS POSSIBLE ACROSS CENTRAL AND EASTERN LAKE ERIE
OVERNIGHT SO HAVE LEFT THE GALE WARNING IN EFFECT WITH WINDS TO 35
KNOTS FOR THE OVERNIGHT HOURS. A SMALL CRAFT ADVISORY HAS BEEN
ISSUED FOR NEARSHORE WATERS WEST OF VERMILLION AND WILL BE NEEDED
FOR THE REMAINDER OF THE NEARSHORE WATERS ON TUESDAY AS NORTHWEST
WINDS OF 15 TO 25 KNOTS CONTINUE TO GENERATE HIGH WAVES ALONG THE
LAKESHORE. WINDS AND WAVES WILL DECREASE TUESDAY NIGHT AS A RIDGE
OF HIGH PRESSURE BUILDS OVER THE LAKE.
HIGH PRESSURE WILL MOVE TO THE EAST AS LOW PRESSURE AND A COLD
FRONT MOVES ACROSS THE LAKE THURSDAY. NORTHWEST WINDS MAY BE
STRONG ENOUGH TO CAUSE SMALL CRAFT ADVISORY CONDITIONS THURSDAY
NIGHT...BUT THEN WINDS SHOULD DIMINISH AS A RIDGE BUILDS OVER THE
LAKE FRIDAY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...WINTER STORM WARNING UNTIL 11 AM EDT THIS MORNING FOR
PAZ001>003.
MARINE...GALE WARNING UNTIL 5 AM EDT EARLY THIS MORNING FOR LEZ061-
145>149-165>169.
SMALL CRAFT ADVISORY UNTIL 4 AM EDT WEDNESDAY FOR LEZ142>144.
&&
$$
SYNOPSIS...KUBINA
NEAR TERM...KIELTYKA
SHORT TERM...KUBINA
LONG TERM...DJB
AVIATION...TK
MARINE...ABE
AREA FORECAST DISCUSSION...UPDATED FOR 12Z TAFS
NWS TWIN CITIES/CHANHASSEN MN
545 AM CDT TUE APR 24 2012
.DISCUSSION...ISSUED 421 AM CDT
STRONG MID LEVEL TEMPERATURE GRADIENT ACROSS THE AREA THIS MORNING
BETWEEN ERN TROUGH AND WRN RIDGE HAS RESULTED IN A NICE BAND OF
WAA/ISENTROPICALLY INDUCED MID LEVEL CLOUD COVER ACROSS ERN HALF OF
THE MPX AREA. LAPS SOUNDINGS ACROSS THE AREA SHOW AIR BELOW H7 IS
QUITE DRY...WHICH IS REFLECTED IN CLOUD HEIGHT AOA 8K FT.
STILL...A FEW 50 DBZ PIXELS IN SHOWERS FROM TIME TO TIME IS AN
INDICATION THAT ENOUGH PRECIP IS BEING GENERATED TO GET SOME
BRIEF SHOWERS TO THE GROUND. HRRR REFLECTIVITY FORECASTS HANDLING
THESE SHOWERS WELL THIS MORNING...AND HAS MOST OF THEM GONE BY 12Z
AS AREA OF ISENTROPIC LIFT PUSHES SOUTH...SO LEFT NOTHING MORE
THAN A SPRINKLE MENTION ACROSS ERN MN THROUGH 15Z. FOR THE REST OF
TODAY...THERMAL GRADIENT AND UPPER JET CONFIGURATION WILL REMAIN
IN PLACE...WHICH MAY RESULT IN CLOUDS REMAINING ACROSS WRN WI MUCH OF
THE DAY. FOR HIGHS...SEEING A STRONG PUSH OF WARM AIR AT H85...BUT
WITH THE DEEP AND COLD TROUGH TO THE EAST...DOES LOOK LIKE WARMER
AIR DOES GET SLOWED UP SOME...WITH HIGHS IN WI LIKELY ONLY GETTING
TO AROUND 60...EVEN IF THE CLOUDS CAN CLEAR OUT THIS AFTERNOON.
OUT IN WRN MN...SHOULD SEE MORE WIDESPREAD 70S TODAY...BUT NOT
EXPECTING ANY 80 DEGREE READINGS. THE +20C ISOTHERM AT H85 WAS A
FAIRLY GOOD DEMARCATION FOR WHERE 80 DEGREE HIGHS WERE OBSERVED
YESTERDAY...AND ALL MODELS KEEP THAT WEST OF MN TODAY.
FOR TONIGHT AND WEDNESDAY...MODELS CONTINUE TO ADVERTISE THE WRN
RIDGE FLATTENING OUT SOME...WITH SHORTWAVE ENERGY AND ASSOCIATED
THUNDERSTORMS CURRENTLY NEAR THE IDAHO CHIMNEY DRIVING A SFC LOW
ACROSS MN. STILL EXPECTING A STRONG WAA PUSH ALONG AND NORTH OF
THE LOW TRACK...WHICH THE SREF/ECMWF CONTINUING TO BRING BASICALLY
STRAIGHT DOWN I-94...WITH BEST RAINFALL CHANCES ALONG AND NORTH OF
THE 94 CORRIDOR AS A RESULT. BEST RAIN CHANCES LOOK TO COME IN
AFTER MIDNIGHT...WITH ELEVATED INSTABILITY STILL LOOKING TO BE MORE
THAN SUFFICIENT TO CONTINUE THE MENTION OF THUNDER. FOR
WEDNESDAY...TO SAY THE FORECAST IS COMPLEX IS AN UNDERSTATEMENT.
BY THE AFTERNOON...SFC LOW LOOKS TO BE IN THE RED WING/LA CROSSE
AREA AS A POLAR FRONT COMES SURGING SOUTH OUT OF CANADA. ANY
PRECIP LOOKS TO CONTINUE TO BE ASSOCIATED WITH THE SFC LOW...BUT
WITH THE FRONT COMING SOUTH IN THE AFTERNOON...DOES LOOK LIKE A
LOW/TRIPLE POINT WILL BE SETTING UP OVER SE MN. WITH TEMPS WELL
INTO THE 70S AND SFC DEWPS IN THE MID 50S AND BULK SHEAR UP AROUND
50 KTS...A SEVERE THREAT WOULD EXIST FOR ANY SFC BASED CONVECTION
THAT CAN TAKE HOLD IN THE AFTERNOON. AT THIS POINT...THE BEST
THREAT OF SEVERE WEATHER LOOKS TO BE JUST SE OF THE AREA...BUT SPC
SREF CONDITIONAL SEVERE WEATHER PROBS FOR WEDNESDAY AFTERNOON DO
SPIKE UP IN SE MN...WITH THE DAY2 OUTLOOK BRINGING MARGINAL SEVERE
UP INTO THE SE MPX CWA. BESIDE THE THUNDER THREAT...THE
TEMPERATURE FORECAST WAS QUITE THE HEADACHE AS WELL. THE 00Z ECMWF
HAS HIGHS UP AROUND 80 FROM RWF DOWN TO FAIRMONT...WITH THE
LADYSMITH AREA ONLY GETTING TO 50. WINDS AHEAD OF THE POLAR FRONT
LOOK TO COME OUT OF THE WSW...SO DOES LOOK LIKE SWRN AREA COULD
REALLY WARM UP QUITE A BIT WEDNESDAY...WHILE MOST MODELS SHOW
SHOWERS/STATUS HANGING ON MOST OF THE DAY ACROSS WI...WITH
TEMPERATURES STRUGGLING TO BUDGE THERE.
THE POLAR FRONT LOOKS DRIVE ANY PRECIP SOUTH AND EAST OF THE AREA
WEDNESDAY NIGHT. AN UPPER 1030S HIGH OVER HUDSON BAY WILL BE
FILTERING MUCH COLDER AND DRIER AIR INTO THE AREA ON
THURSDAY....WITH HIGHS ACROSS WRN/SRN MN RUNNING AS MUCH AS 20
DEGREES COLDER ON THURSDAY THAN ON WEDNESDAY. IT IS THE HIGH AND
ASSOCIATED DRY AIR THAT WILL PLAY A LARGE ROLE IN NRN EXTENT OF
PRECIP FRIDAY INTO SATURDAY. THE 00Z GEM/ECMWF BASICALLY KEEP ALL
BUT THE I-90 CORRIDOR DRY DURING THIS PERIOD...WITH THE ECMWF
DROPPING DEWPS DOWN INTO THE TEENS AND 20S BY FRIDAY MORNING ACROSS
THE AREA. EVEN THE GFS HAS PULLED PRECIP FURTHER SOUTH...WITH THE
NE CWA LOOKING TO REMAIN DRY WITH THIS SYSTEM. GIVEN THE STRENGTH
OF THE HUDSON HIGH...AND THE REX BLOCK PROGGED TO BE OVER SRN
CANADA BY THE END OF THE WEEK...LIKE THE IDEA OF IT BEING
DIFFICULT FOR PRECIP TO MAKE IT MUCH FURTHER NORTH THAN THE MN
RIVER...SIMILAR TO WHAT WE SAW WITH THE SYSTEM THAT IMPACTED
SOUTHERN MN WED NIGHT/THU OF LAST WEEK. WHERE EVER THE RAIN DOES
END UP THOUGH...IT DOES LOOK TO BE RATHER RAW...WITH TEMPS LIKELY
STRUGGLING INTO THE LOWER 40S.
&&
.AVIATION.../12Z TAF ISSUANCE/
WDLY SCT -SHRA SHUD BE S OF MSP BY 12Z LEAVING SCT TO OCNL BKN CLDS
AROUND 10K FOR RMDR OF DAY. SFC WINDS WILL BE LIGHT...GENERALY AOB
10 KTS WHICH WILL CAUSE SOME VARIABILITY IN DIRECTION...ESPECIALLLY
AT WI TAFS AND TO SOME EXTEND AT MSP. SCT SHWRS WILL PUSH INTO W MN
BY 06Z AND ACRS AREA AROUND 10Z. EXPECT CONDITIONS TO REMAIN
VFR...BUT IF SUFFICIENT PCPN COULD SEE HIGH END MVFR ESPECIALLY AT
STC/MSP AND WI TAFS LATE IN PRD.
MSP...WILL CONTINUE TO SEE SOME VARIABILITY IN WIND DIRECION INTO
THE MID MORNING...BUT WINDS WILL GENERALLY BE IN RANGE FROM 080 TO
130. SCT -SHWRS WILL BE S OF MSP BY 12Z LEAVING SCT-BKN100 FOR THE
DAY. COULD SEE HIGH END MVFR CONDS AFTER 10Z IN SHWRS.
//OUTLOOK...TUESDAY NIGHT THROUGH SUNDAY...
.WED...CHANCE OF -SHRA/-TSRA INTO WEDNESDAY WITH MVFR CIGS/VSBY
POSSIBLE.
.WED NIGHT AND THU...VFR UNDER HIGH PRESSURE.
.THU NIGHT THRU SUN...CHC OF -SHRA BUT MAINLY VFR.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
MPG/BAP
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1006 AM CDT TUE APR 24 2012
.DISCUSSION...THIS MORNING A WARM/STATIONARY FRONTAL BOUNDARY
FROM SOUTHERN SASKATCHEWAN THROUGH CENTRAL SOUTH DAKOTA AND LYING
ACROSS WESTERN NORTH DAKOTA WILL BE THE FOCUS FOR ISOLATED
THUNDERSTORMS TODAY. SATELLITE PICS AND RADAR SHOW SOME SCATTERED
SHOWERS NOW IN NORTH CENTRAL NORTH DAKOTA. THE LATEST HRRR MESO
MODEL DOES INDICATE THIS AREA FOR FOCUS DURING THE NEXT 3 HOURS.
SO ANTICIPATE THUNDERSTORMS INITIALLY IN THE NORTH CENTRAL
MOVING SOUTHEAST. FROM THE SPC OUTLOOK THERE IS POTENTIAL FOR AN
ISOLATED SEVERE STORM THIS AFTERNOON IF THE CELLS BREAK THE
ELEVATED MIXED LAYER CAP. SO ADDED CHANCE FOR THUNDERSTORMS AND
RAISED THE POPS NORTH CENTRAL. OTHERWISE CURRENT FORECAST LOOKS
GOOD.
&&
.AVIATION...
A FEW SHOWERS WILL PERSIST INVOF KMOT THIS MORNING IN RESPONSE
TO A WEAK SHORT WAVE TROUGH...AND HAVE INCLUDED A BRIEF VCSH MENTION
THROUGH 17Z. ISOLATED HIGH BASED THUNDERSTORMS DURING THE LATE
AFTERNOON AND EARLY EVENING HOURS WILL BE THE MAIN IMPACT THROUGH
25/12Z. AT THIS TIME...THE EXPECTED COVERAGE AND LOW PROBABILITY OF
THUNDERSTORMS DO NOT WARRANT MORE THAN A CB GROUP IN TAFS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...WAA
AVIATION...JV
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
945 AM CDT TUE APR 24 2012
.DISCUSSION...FORECAST CHALLENGE FOR UPDATE CONCERNS MAXIMUM
TEMPERATURES AND CONVECTIVE POTENTIAL. SURFACE BOUNDARY EXTENDS
FROM NW CORNER OF ND NEAR ISN TO SE CORNER OF SD NEAR FSD WITH
SURFACE LOWS ACROSS S CENTRAL SASK AND FSD. BOUNDARY FORECAST BY
MODELS TO REACH CENTRAL ND BY 00Z. REGION WILL REMAIN IN WARM SECTOR
FOR THE DAY. CLOUD COVER AHEAD OF BOUNDARY SPARSE WITH MAINLY SOME
SCT ACCAS WHICH SHOULD ALLOW FOR GOOD SOLAR TODAY. LAST TWO DAYS MAX
TEMPERATURES HAVE BEEN UNDERESTIMATED SO WILL STICK WITH CURRENT
FORECAST WHICH NUDGED MAX TEMPERATURES ABOVE FAVORED NUMERICAL
GUIDANCE. WITH REGION IN WARM SECTOR RUC SHOWING RESPECTABLE
INSTABILITY AND CAPE HOWEVER AIRMASS FAIRLY CAPPED WITH CONVECTIVE
TEMPERATURES WELL INTO THE 80S ALONG WITH SUFFICIENT CIN TO INHIBIT
CONVECTION. RUC MAY BE OVERDOING INSTABILITY AS IT BRINGS MID 50
DEWPOINTS WELL NORTH INTO ND WHICH MAY BE A LITTLE OVERDONE. LOW
LEVEL MOIST AXIS EXTENDS FROM SE SD INTO CENTRAL ND NEAR BOUNDARY
AND THIS LOOKS LIKE FAVORED AREA FOR ANY AFTERNOON DEVELOPMENT.
BETTER CHANCE THIS EVENING WHEN MORE FAVORED UPPER SUPPORT ARRIVES
SO WILL FORECAST DRY DURING THE DAY.
&&
.AVIATION...
VFR CONDITIONS TODAY WITH LIGHT SE WINDS AND INCREASING MID
CLOUDS THIS AFTERNOON AND EVENING AS CHC OF TSTORMS OR SHRA
DEVELOPS. WIND SHIFT OCCURS LATER TONIGHT AS COLD FRONT MOVES
THROUGH.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
VOELKER
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
430 PM EDT TUE APR 24 2012
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW
&&
.SYNOPSIS...
ISSUED AT 340 PM EDT TUE APR 24 2012
A WARM FRONT TAKING SHAPE OVER THE PLAINS AND AN UPPER WAVE MOVING
IN FROM THE NORTHERN PLAINS SHOULD BRING CHANCES FOR THUNDERSTORMS
TO THE AREA WEDNESDAY AFTERNOON AND INTO THURSDAY. BY THURSDAY NIGHT
ANOTHER FRONTAL SYSTEM WILL BRING MORE CHANCES TO THE AREA FOR MUCH
OF THE WEEKEND BY STALLING THE FRONT AND HAVING SEVERAL WAVES MOVE
ALONG IT. BY SUNDAY NIGHT UPPER RIDGING FINALLY STARTS MOVING IN TO
DRY THINGS OUT UNTIL TUESDAY.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 340 PM EDT TUE APR 24 2012
RADAR ECHOES ACROSS WESTERN INDIANA AT 19Z ARE NOT PRODUCING
ANYTHING BUT VIRGA AT THIS POINT. THOSE OVER ILLINOIS ARE
OCCASIONALLY BEING OBSERVED BY ASOS BUT STILL HAVE NOT SEEN ANYTHING
MEASURABLE THERE EITHER. WITH THIS IN MIND AND NO FORCING ARRIVING
TO INTENSIFY THE LIFT OR ADVECT IN MUCH BETTER MOISTURE HAVE DECIDED
TO GO DRIER THAN GUIDANCE AND HRRR AND MAINTAIN JUST A SLIGHT CHANCE
IN THE SOUTHWESTERN COUNTIES WHERE DEW POINTS AT LEAST ARE IN THE
30S AND LOW 40S. WITH THE DRY AIR IT WILL JUST BE VERY DIFFICULT FOR
ANY SORT OF MEASURABLE PRECIPITATION TO TAKE PLACE. WENT DRY AFTER
6Z. FOR TEMPERATURES STUCK CLOSE TO WARMER MAV NUMBERS AS THESE HAVE
BEEN VERIFYING BETTER LATELY AND THAT PRODUCED LOWS IN THE 40S.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
ISSUED AT 340 PM EDT TUE APR 24 2012
FORECAST FOCUS IS ON POPS/THUNDER POTENTIAL. MODELS ARE IN GOOD
AGREEMENT AND WILL USE A CONSENSUS APPROACH FOR THE MOST PART.
WEDNESDAY SHOULD START OUT DRY WITH INCREASING CLOUDS AS A WARM
FRONT FIRMS UP A BIT MORE SOUTH OF THE AREA AND AN UPPER WAVE
APPROACHES FROM THE NORTHWEST. BY AFTERNOON THESE AFOREMENTIONED
FEATURES SHOULD BRING CHANCES FOR THUNDERSTORMS TO THE AREA.
OVERNIGHT THE SURFACE LOW WILL DRAG A COLD FRONT THROUGH THE AREA
AND AN UPPER WAVE WILL MOVE THROUGH AS WELL...AND THIS SHOULD BRING
THE BEST CHANCES FOR PRECIPITATION IN THE SHORT TERM. THUS WENT
ALONG WITH LIKELIES IN THE MAV. DID CUT THE NORTH FROM THEIR LOW END
CATEGORICAL OF THE MAV AS COVERAGE MAY NOT BE QUITE THAT GREAT BUT
THOUGHT HIGH END LIKELIES CAPTURED THE THREAT WELL. ENTIRE FORECAST
AREA IS IN A DAY 2 SLIGHT RISK BASED ON STEEP MID LEVEL LAPSE RATES
BEING ABLE TO AID IN HAIL PRODUCTION...BUT WITH MODELS OVERDOING
MOISTURE RETURN AND THUS INSTABILITY THINK WIDESPREAD SEVERE
POTENTIAL IS LOW AND MORE INCLINED TO BELIEVE MOST STORMS WILL
PRODUCE LOW END HAIL AND ONLY ISOLATED STORMS WILL PRODUCE EVEN
QUARTER SIZE HAIL.
FOR THURSDAY THERE IS SOME DISAGREEMENT ON HOW FAR SOUTH THE FRONT
WILL GET. THUS THURSDAY MORNING MAINTAINED A CHANCE ACROSS SOUTHERN
HALF OR SO OF THE AREA TAPERING TO DRY IN THE NORTH. BY AFTERNOON
THE FRONT SHOULD BE FAR ENOUGH AWAY THAT DROPPED TO JUST A SLIGHT
CHANCE ON THE SOUTHERN BORDER. MODELS ARE FASTER WITH PROGRESSING
ANOTHER FRONT FROM THE PLAINS HOWEVER AND BRINGING SOME ISENTROPIC
LIFT OVERNIGHT THURSDAY SO EXPANDED POPS A BIT MORE TO ALL BUT THE
NORTHEASTERN COUNTIES. ON FRIDAY THIS FRONT SHOULD BE MOVING NORTH
INTO THE AREA AND WENT WITH CHANCE ACROSS THE ENTIRE AREA. DEPENDING
ON IF THIS FRONT STALLS AND STAYS FAIRLY STATIONARY INTO THE WEEKEND
AS SOME MODELS ARE PREDICTING...COULD SEE SOME DECENT RAINFALL
AMOUNTS.
FOR TEMPERATURES GENERALLY WENT CLOSER TO WARMER GUIDANCE NUMBERS AS
THIS HAS BEEN VERIFYING BETTER LATELY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
ISSUED AT 340 PM EDT TUE APR 24 2012
THERE IS A BETTER CONSENSUS AMONG THE MODELS ON WHEN THE
PRECIPITATION WILL OCCUR DURING THE EXTENDED PERIOD. REALLY THE BEST
CHANCES WILL RUN FROM FRIDAY THROUGH SATURDAY...WITH SOME LOWER
CHANCES SATURDAY NIGHT AND ONLY A SLIGHT CHANCE BY SUNDAY. FELT
CONFIDENT ENOUGH IN LONG TERM ENSEMBLES TO BUMPED POPS UP TO LIKELY
FRIDAY NIGHT THROUGH SATURDAY...THOUGH CHANCES FOR CONVECTION LOOK
LOW/WEAK AND KEPT THUNDER MENTION AT CHANCE TO ISOLATED. THE BULK OF
THE INSTABILITY LIES FARTHER SOUTH OF THE FORECAST AREA...CLOSER TO
THE FRONTAL BOUNDARY. LOOKS DRY FOR EARLY NEXT WORK WEEK AS RIDGE
BUILDS BACK OVER THE REGION.
&&
.AVIATION /DISCUSSION FOR THE 242100Z TAF UPDATES/...
ISSUED AT 430 PM EDT TUE APR 24 2012
HAD TO DECREASE WINDS BASED ON OBSERVATIONAL TRENDS...OTHERWISE NO
CHANGES.
PREVIOUS DISCUSSION FOLLOWS...
VFR CONDITIONS EXPECTED FOR THE NEXT 24 HRS...
GENERALLY QUIET WEATHER CONTINUES FOR CENTRAL INDIANA AS A RIDGE OF
HIGH PRESSURE SLOWLY SLIDES EAST OVER THE REGION. A FEW MID LEVEL
CLOUDS AND POSSIBLY A FEW SPRINKLES (THOUGH THE LATTER HAVE NOT
BEEN REPORTED YET) HAVE MOVED OVER THE WESTERN CWA. THIS CLOUD DECK
WILL SLOWLY SHIFT EASTWARD AND ENVELOPE THE REST OF THE TAF SITES
THIS AFTERNOON. THIS WILL NOT HAVE AN IMPACT ON THE FLIGHT
CATEGORY AS VFR CONDITIONS WILL BE THE PREVAILING FLIGHT CATEGORY
FOR ENTIRE TAF PERIOD.
HOWEVER...AS EXPECTED WINDS BEGAN TO PICK UP AND GUST ONCE AGAIN
AROUND 15-16Z THIS AFTERNOON...THOUGH NOT EVEN CLOSE TO AS STRONG
AS YESTERDAY...THIS AFTERNOON ONLY AROUND 20-22KT. LOCATIONS SUCH
AS KHUF AND KBMG ARE NOT EXPECTING TO GUST OFTEN SO THIS WAS
LEFT OUT OF THEIR TAFS.
CLOUDS WILL BE ON THE INCREASE TOMORROW AHEAD OF A FRONT AND VCSH
WAS INTRODUCED BY THE END OF KIND TAF PERIOD. MORE WIDESPREAD RAIN
SHOWERS ARE ANTICIPATED BY WED NIGHT WITH A CHANCE FOR
THUNDERSTORMS...SO THIS WILL LIKELY BE ADDED IN FORTHCOMING
AVIATION FORECAST ISSUANCES.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CP
NEAR TERM...CP
SHORT TERM...CP
LONG TERM....SMF
AVIATION...SMF/MK
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
342 PM EDT TUE APR 24 2012
.UPDATE...
THE SYNOPSIS...NEAR TERM...SHORT TERM
AND LONG TERM SECTIONS HAVE BEEN UPDATED BELOW
&&
.SYNOPSIS...
ISSUED AT 340 PM EDT TUE APR 24 2012
A WARM FRONT TAKING SHAPE OVER THE PLAINS AND AN UPPER WAVE MOVING
IN FROM THE NORTHERN PLAINS SHOULD BRING CHANCES FOR THUNDERSTORMS
TO THE AREA WEDNESDAY AFTERNOON AND INTO THURSDAY. BY THURSDAY NIGHT
ANOTHER FRONTAL SYSTEM WILL BRING MORE CHANCES TO THE AREA FOR MUCH
OF THE WEEKEND BY STALLING THE FRONT AND HAVING SEVERAL WAVES MOVE
ALONG IT. BY SUNDAY NIGHT UPPER RIDGING FINALLY STARTS MOVING IN TO
DRY THINGS OUT UNTIL TUESDAY.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 340 PM EDT TUE APR 24 2012
RADAR ECHOES ACROSS WESTERN INDIANA AT 19Z ARE NOT PRODUCING
ANYTHING BUT VIRGA AT THIS POINT. THOSE OVER ILLINOIS ARE
OCCASIONALLY BEING OBSERVED BY ASOS BUT STILL HAVE NOT SEEN ANYTHING
MEASURABLE THERE EITHER. WITH THIS IN MIND AND NO FORCING ARRIVING
TO INTENSIFY THE LIFT OR ADVECT IN MUCH BETTER MOISTURE HAVE DECIDED
TO GO DRIER THAN GUIDANCE AND HRRR AND MAINTAIN JUST A SLIGHT CHANCE
IN THE SOUTHWESTERN COUNTIES WHERE DEW POINTS AT LEAST ARE IN THE
30S AND LOW 40S. WITH THE DRY AIR IT WILL JUST BE VERY DIFFICULT FOR
ANY SORT OF MEASURABLE PRECIPITATION TO TAKE PLACE. WENT DRY AFTER
6Z. FOR TEMPERATURES STUCK CLOSE TO WARMER MAV NUMBERS AS THESE HAVE
BEEN VERIFYING BETTER LATELY AND THAT PRODUCED LOWS IN THE 40S.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
ISSUED AT 340 PM EDT TUE APR 24 2012
FORECAST FOCUS IS ON POPS/THUNDER POTENTIAL. MODELS ARE IN GOOD
AGREEMENT AND WILL USE A CONSENSUS APPROACH FOR THE MOST PART.
WEDNESDAY SHOULD START OUT DRY WITH INCREASING CLOUDS AS A WARM
FRONT FIRMS UP A BIT MORE SOUTH OF THE AREA AND AN UPPER WAVE
APPROACHES FROM THE NORTHWEST. BY AFTERNOON THESE AFOREMENTIONED
FEATURES SHOULD BRING CHANCES FOR THUNDERSTORMS TO THE AREA.
OVERNIGHT THE SURFACE LOW WILL DRAG A COLD FRONT THROUGH THE AREA
AND AN UPPER WAVE WILL MOVE THROUGH AS WELL...AND THIS SHOULD BRING
THE BEST CHANCES FOR PRECIPITATION IN THE SHORT TERM. THUS WENT
ALONG WITH LIKELIES IN THE MAV. DID CUT THE NORTH FROM THEIR LOW END
CATEGORICAL OF THE MAV AS COVERAGE MAY NOT BE QUITE THAT GREAT BUT
THOUGHT HIGH END LIKELIES CAPTURED THE THREAT WELL. ENTIRE FORECAST
AREA IS IN A DAY 2 SLIGHT RISK BASED ON STEEP MID LEVEL LAPSE RATES
BEING ABLE TO AID IN HAIL PRODUCTION...BUT WITH MODELS OVERDOING
MOISTURE RETURN AND THUS INSTABILITY THINK WIDESPREAD SEVERE
POTENTIAL IS LOW AND MORE INCLINED TO BELIEVE MOST STORMS WILL
PRODUCE LOW END HAIL AND ONLY ISOLATED STORMS WILL PRODUCE EVEN
QUARTER SIZE HAIL.
FOR THURSDAY THERE IS SOME DISAGREEMENT ON HOW FAR SOUTH THE FRONT
WILL GET. THUS THURSDAY MORNING MAINTAINED A CHANCE ACROSS SOUTHERN
HALF OR SO OF THE AREA TAPERING TO DRY IN THE NORTH. BY AFTERNOON
THE FRONT SHOULD BE FAR ENOUGH AWAY THAT DROPPED TO JUST A SLIGHT
CHANCE ON THE SOUTHERN BORDER. MODELS ARE FASTER WITH PROGRESSING
ANOTHER FRONT FROM THE PLAINS HOWEVER AND BRINGING SOME ISENTROPIC
LIFT OVERNIGHT THURSDAY SO EXPANDED POPS A BIT MORE TO ALL BUT THE
NORTHEASTERN COUNTIES. ON FRIDAY THIS FRONT SHOULD BE MOVING NORTH
INTO THE AREA AND WENT WITH CHANCE ACROSS THE ENTIRE AREA. DEPENDING
ON IF THIS FRONT STALLS AND STAYS FAIRLY STATIONARY INTO THE WEEKEND
AS SOME MODELS ARE PREDICTING...COULD SEE SOME DECENT RAINFALL
AMOUNTS.
FOR TEMPERATURES GENERALLY WENT CLOSER TO WARMER GUIDANCE NUMBERS AS
THIS HAS BEEN VERIFYING BETTER LATELY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
ISSUED AT 340 PM EDT TUE APR 24 2012
THERE IS A BETTER CONSENSUS AMONG THE MODELS ON WHEN THE
PRECIPITATION WILL OCCUR DURING THE EXTENDED PERIOD. REALLY THE BEST
CHANCES WILL RUN FROM FRIDAY THROUGH SATURDAY...WITH SOME LOWER
CHANCES SATURDAY NIGHT AND ONLY A SLIGHT CHANCE BY SUNDAY. FELT
CONFIDENT ENOUGH IN LONG TERM ENSEMBLES TO BUMPED POPS UP TO LIKELY
FRIDAY NIGHT THROUGH SATURDAY...THOUGH CHANCES FOR CONVECTION LOOK
LOW/WEAK AND KEPT THUNDER MENTION AT CHANCE TO ISOLATED. THE BULK OF
THE INSTABILITY LIES FARTHER SOUTH OF THE FORECAST AREA...CLOSER TO
THE FRONTAL BOUNDARY. LOOKS DRY FOR EARLY NEXT WORK WEEK AS RIDGE
BUILDS BACK OVER THE REGION.
&&
.AVIATION /DISCUSSION FOR THE 241800Z TAF ISSUANCE/...
ISSUED AT 1256 PM EDT TUE APR 24 2012
VFR CONDITIONS EXPECTED FOR THE NEXT 24 HRS...
GENERALLY QUIET WEATHER CONTINUES FOR CENTRAL INDIANA AS A RIDGE OF
HIGH PRESSURE SLOWLY SLIDES EAST OVER THE REGION. A FEW MID LEVEL
CLOUDS AND POSSIBLY A FEW SPRINKLES (THOUGH THE LATTER HAVE NOT
BEEN REPORTED YET) HAVE MOVED OVER THE WESTERN CWA. THIS CLOUD DECK
WILL SLOWLY SHIFT EASTWARD AND ENVELOPE THE REST OF THE TAF SITES
THIS AFTERNOON. THIS WILL NOT HAVE AN IMPACT ON THE FLIGHT
CATEGORY AS VFR CONDITIONS WILL BE THE PREVAILING FLIGHT CATEGORY
FOR ENTIRE TAF PERIOD.
HOWEVER...AS EXPECTED WINDS BEGAN TO PICK UP AND GUST ONCE AGAIN
AROUND 15-16Z THIS AFTERNOON...THOUGH NOT EVEN CLOSE TO AS STRONG
AS YESTERDAY...THIS AFTERNOON ONLY AROUND 20-22KT. LOCATIONS SUCH
AS KHUF AND KBMG ARE NOT EXPECTING TO GUST OFTEN SO THIS WAS
LEFT OUT OF THEIR TAFS.
CLOUDS WILL BE ON THE INCREASE TOMORROW AHEAD OF A FRONT AND VCSH
WAS INTRODUCED BY THE END OF KIND TAF PERIOD. MORE WIDESPREAD RAIN
SHOWERS ARE ANTICIPATED BY WED NIGHT WITH A CHANCE FOR
THUNDERSTORMS...SO THIS WILL LIKELY BE ADDED IN FORTHCOMING
AVIATION FORECAST ISSUANCES.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CP
NEAR TERM...CP
SHORT TERM...CP
LONG TERM....SMF
AVIATION...SMF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
213 PM CDT TUE APR 24 2012
.UPDATE...
.AVIATION.../18Z TAF ISSUANCE/
VFR CONDITIONS EXPECTED THROUGH THE PERIOD. THE BIGGEST CONCERN IS
THE CHANCE OF THUNDERSTORMS FOR THE WESTERN PART OF THE STATE LATE
TONIGHT. WARM ADVECTION BEGINS LATE TONIGHT WITH THE INSTABILITY
GRADIENT INITIALLY STRONGEST OVER THAT AREA OF THE STATE. WILL
JUST INCLUDE A VCTS AT KAXN AT THIS TIME. OTHERWISE AREAS OF
SHOWERS WITH LOWER END VFR CIGS /050-060/ SPREADING ACROSS OTHER
TAF SITES LATE TONIGHT AND WEDNESDAY MORNING. WILL NEED TO WATCH
THE POSSIBILITY OF THUNDER OTHER SITES IN LATER FORECASTS. WINDS
GENERALLY EAST TO SOUTHEAST 5 TO 10 KNOTS...BUT SWITCHING TO
NORTHWEST NEAR THE END OF THE PERIOD VCNTY OF KAXN AND KRWF.
KMSP...JUST SCT MID AND HIGH CLOUDS FOR THE AFTERNOON AND
EVENING...THEN INCREASING CHANCE OF SHOWERS AFTER 09Z WITH LOWER
END VFR CIGS / 050-060 /. HAVE NOT INCLUDED THUNDER AT THIS POINT
BUT SOMETHING TO WATCH IN LATER FORECASTS. COLD FRONT TO MOVE INTO
THE AREA AFTER 21Z WITH A WIND SHIFT TO THE NORTHWEST. OTHERWISE
GENERALLY EAST TO SOUTHEAST 5 TO 10 KNOTS BUT SOME INCREASE 10 TO
15 KNOTS WEDNESDAY MORNING.
&&
.DISCUSSION...
STRONG MID LEVEL TEMPERATURE GRADIENT ACROSS THE AREA THIS MORNING
BETWEEN ERN TROUGH AND WRN RIDGE HAS RESULTED IN A NICE BAND OF
WAA/ISENTROPICALLY INDUCED MID LEVEL CLOUD COVER ACROSS ERN HALF OF
THE MPX AREA. LAPS SOUNDINGS ACROSS THE AREA SHOW AIR BELOW H7 IS
QUITE DRY...WHICH IS REFLECTED IN CLOUD HEIGHT AOA 8K FT.
STILL...A FEW 50 DBZ PIXELS IN SHOWERS FROM TIME TO TIME IS AN
INDICATION THAT ENOUGH PRECIP IS BEING GENERATED TO GET SOME
BRIEF SHOWERS TO THE GROUND. HRRR REFLECTIVITY FORECASTS HANDLING
THESE SHOWERS WELL THIS MORNING...AND HAS MOST OF THEM GONE BY 12Z
AS AREA OF ISENTROPIC LIFT PUSHES SOUTH...SO LEFT NOTHING MORE
THAN A SPRINKLE MENTION ACROSS ERN MN THROUGH 15Z. FOR THE REST OF
TODAY...THERMAL GRADIENT AND UPPER JET CONFIGURATION WILL REMAIN
IN PLACE...WHICH MAY RESULT IN CLOUDS REMAINING ACROSS WRN WI MUCH OF
THE DAY. FOR HIGHS...SEEING A STRONG PUSH OF WARM AIR AT H85...BUT
WITH THE DEEP AND COLD TROUGH TO THE EAST...DOES LOOK LIKE WARMER
AIR DOES GET SLOWED UP SOME...WITH HIGHS IN WI LIKELY ONLY GETTING
TO AROUND 60...EVEN IF THE CLOUDS CAN CLEAR OUT THIS AFTERNOON.
OUT IN WRN MN...SHOULD SEE MORE WIDESPREAD 70S TODAY...BUT NOT
EXPECTING ANY 80 DEGREE READINGS. THE +20C ISOTHERM AT H85 WAS A
FAIRLY GOOD DEMARCATION FOR WHERE 80 DEGREE HIGHS WERE OBSERVED
YESTERDAY...AND ALL MODELS KEEP THAT WEST OF MN TODAY.
FOR TONIGHT AND WEDNESDAY...MODELS CONTINUE TO ADVERTISE THE WRN
RIDGE FLATTENING OUT SOME...WITH SHORTWAVE ENERGY AND ASSOCIATED
THUNDERSTORMS CURRENTLY NEAR THE IDAHO CHIMNEY DRIVING A SFC LOW
ACROSS MN. STILL EXPECTING A STRONG WAA PUSH ALONG AND NORTH OF
THE LOW TRACK...WHICH THE SREF/ECMWF CONTINUING TO BRING BASICALLY
STRAIGHT DOWN I-94...WITH BEST RAINFALL CHANCES ALONG AND NORTH OF
THE 94 CORRIDOR AS A RESULT. BEST RAIN CHANCES LOOK TO COME IN
AFTER MIDNIGHT...WITH ELEVATED INSTABILITY STILL LOOKING TO BE MORE
THAN SUFFICIENT TO CONTINUE THE MENTION OF THUNDER. FOR
WEDNESDAY...TO SAY THE FORECAST IS COMPLEX IS AN UNDERSTATEMENT.
BY THE AFTERNOON...SFC LOW LOOKS TO BE IN THE RED WING/LA CROSSE
AREA AS A POLAR FRONT COMES SURGING SOUTH OUT OF CANADA. ANY
PRECIP LOOKS TO CONTINUE TO BE ASSOCIATED WITH THE SFC LOW...BUT
WITH THE FRONT COMING SOUTH IN THE AFTERNOON...DOES LOOK LIKE A
LOW/TRIPLE POINT WILL BE SETTING UP OVER SE MN. WITH TEMPS WELL
INTO THE 70S AND SFC DEWPS IN THE MID 50S AND BULK SHEAR UP AROUND
50 KTS...A SEVERE THREAT WOULD EXIST FOR ANY SFC BASED CONVECTION
THAT CAN TAKE HOLD IN THE AFTERNOON. AT THIS POINT...THE BEST
THREAT OF SEVERE WEATHER LOOKS TO BE JUST SE OF THE AREA...BUT SPC
SREF CONDITIONAL SEVERE WEATHER PROBS FOR WEDNESDAY AFTERNOON DO
SPIKE UP IN SE MN...WITH THE DAY2 OUTLOOK BRINGING MARGINAL SEVERE
UP INTO THE SE MPX CWA. BESIDE THE THUNDER THREAT...THE
TEMPERATURE FORECAST WAS QUITE THE HEADACHE AS WELL. THE 00Z ECMWF
HAS HIGHS UP AROUND 80 FROM RWF DOWN TO FAIRMONT...WITH THE
LADYSMITH AREA ONLY GETTING TO 50. WINDS AHEAD OF THE POLAR FRONT
LOOK TO COME OUT OF THE WSW...SO DOES LOOK LIKE SWRN AREA COULD
REALLY WARM UP QUITE A BIT WEDNESDAY...WHILE MOST MODELS SHOW
SHOWERS/STATUS HANGING ON MOST OF THE DAY ACROSS WI...WITH
TEMPERATURES STRUGGLING TO BUDGE THERE.
THE POLAR FRONT LOOKS DRIVE ANY PRECIP SOUTH AND EAST OF THE AREA
WEDNESDAY NIGHT. AN UPPER 1030S HIGH OVER HUDSON BAY WILL BE
FILTERING MUCH COLDER AND DRIER AIR INTO THE AREA ON
THURSDAY....WITH HIGHS ACROSS WRN/SRN MN RUNNING AS MUCH AS 20
DEGREES COLDER ON THURSDAY THAN ON WEDNESDAY. IT IS THE HIGH AND
ASSOCIATED DRY AIR THAT WILL PLAY A LARGE ROLE IN NRN EXTENT OF
PRECIP FRIDAY INTO SATURDAY. THE 00Z GEM/ECMWF BASICALLY KEEP ALL
BUT THE I-90 CORRIDOR DRY DURING THIS PERIOD...WITH THE ECMWF
DROPPING DEWPS DOWN INTO THE TEENS AND 20S BY FRIDAY MORNING ACROSS
THE AREA. EVEN THE GFS HAS PULLED PRECIP FURTHER SOUTH...WITH THE
NE CWA LOOKING TO REMAIN DRY WITH THIS SYSTEM. GIVEN THE STRENGTH
OF THE HUDSON HIGH...AND THE REX BLOCK PROGGED TO BE OVER SRN
CANADA BY THE END OF THE WEEK...LIKE THE IDEA OF IT BEING
DIFFICULT FOR PRECIP TO MAKE IT MUCH FURTHER NORTH THAN THE MN
RIVER...SIMILAR TO WHAT WE SAW WITH THE SYSTEM THAT IMPACTED
SOUTHERN MN WED NIGHT/THU OF LAST WEEK. WHERE EVER THE RAIN DOES
END UP THOUGH...IT DOES LOOK TO BE RATHER RAW...WITH TEMPS LIKELY
STRUGGLING INTO THE LOWER 40S.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
MPG/JPR
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
346 PM CDT Tue Apr 24 2012
.DISCUSSION...
In the short term, primary concerns remain with slight convective
chances through Wednesday along with temperatures.
This afternoon, pesky altocumulus and cirrostratus have limited the
upwards extend of temperatures to some degree. However, many areas
will still climb nearly 10-15 degrees above seasonal normals. The
warmest temperatures this afternoon have been located over central
Kansas and southern Nebraska where many locations are now in the
middle 90s. This airmass will gradually move eastward during the
overnight hours.
Tonight: 18z NAM, high-res WRF and HRRR continue to generate isolated to
scattered showers or thunderstorms late tonight across central and
southeastern Kansas along with western Missouri. This activity seems
to be tied to a weak shortwave expected to cross eastward out of the
central Rockies overnight. A slightly amplified low level jet will
push an additional surge of mid-level moisture eastward, with an
increase in elevated instability above 600 mb. An incredibly dry
lower half of the troposphere should limit widespread precipitation,
but if a thunderstorm could form would have to watch for the
potential for some sort of stronger wind gust or heat burst.
Wednesday: GFS which has handled today`s cloud cover adequately well
is less bullish with mid-level cloud cover with EML shifting further
east. Mid-level AC may fester Wednesday morning in central Missouri,
delaying the rapid warmup. However, the remainder of the CWA will be highly
capped, allowing for a significant warmup to near record levels in some
locations. Fast moving shortwave trough will race into the western
Great Lakes late Wednesday afternoon with a ill-defined surface
trough over northern Missouri. Models still point to little in the
way of development along this boundary as best dynamics are focused
in the Great Lakes with the progressive shortwave. There may be
enough surface convergence for a slightly higher chance for late
afternoon or evening thunderstorms in northeastern Missouri.
Wednesday night and Thursday: Models have again shifted the surface
boundary a bit further south into central Missouri Wednesday night,
with an slightly stronger influence from cooler Canadian air
possible. Northeast winds should hold temperatures still above
normal, but will lower temperatures a few degrees Thursday. By
Thursday night, the next round of warm advection precipitation
should begin as the next upper low begins to eject out of the
southwestern United States.
Dux
Medium Range (Friday through Tuesday)...
A quick deamplification of the upper pattern will bring about a more
progressive and stormier pattern for the extended period. As upper
ridging breaks down over the Midwest, a weak negatively-tilted
shortwave will eject into the Plains early Friday, and quickly
deamplify as it becomes absorbed by mean Great Lakes troughing on
Saturday. The result will be a quickly filling surface low that is
forecast to track across southern or central Missouri Friday night.
Going off the more stable GFS solution suggests a more progressive
and southerly forecast track that keeps much of the forecast area in
the cool sector on Friday. This solution is backed up by the latest
NAM which is even further south. This also sets up a tight
baroclinic region marking the difference between temperatures near
50 across the north and in the mid 70s south. Bulk of precipitation
Friday and Friday night will be focused near and just north of this
boundary, which looks to set up near or just south of the US 50
corridor. Can`t rule out some elevated small hailers on Friday but
any appreciable severe threat will remain south of the boundary, and
capping may keep that threat to a minimum.
Continued to lean toward the more progressive GFS solution for
Saturday and Sunday so brought PoPs lower than consensus numbers for
this period. In continued quasizonal flow, the next wave to impact
the region will arrive Monday night and Tuesday. Surface baroclinic
region will remain south of the region through early next week
maintaining below average temperatures through the period.
Hawblitzel
&&
.CLIMATE...
Record highs for Wednesday:
CITY...........NORMAL HIGH........RECORD HIGH
KANSAS CITY....69 DEGREES.........91 IN 1989
ST. JOESPH.....68 DEGREES.........92 IN 1989
DUX
&&
.AVIATION...
For the 18Z TAFs: VFR conditions are expected over the terminals
through Wednesday morning. Edge of warm air aloft continues to push
eastward over the terminals resulting in scattered mid-level clouds
through the overnight hours. It is possible to have a few high based
showers or even thunderstorms later tonight as the low level jet
increases. However, probability of impacting the terminals is too low
to include at this time.
Winds are expected to turn more southerly tonight, before veering
back to the southwest for the daytime hours of Wednesday.
Dux
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
WFO EAX
AREA FORECAST DISCUSSION
NWS HASTINGS NE
244 PM CDT TUE APR 24 2012
.SHORT TERM...TUESDAY NIGHT THROUGH WEDNESDAY.
UPPER LEVEL ANALYSIS INDICATES A STRONG UPPER LEVEL RIDGE HAS BUILT
IN ACROSS THE WESTERN HALF OF THE UNITED STATES. ALONG THIS RIDGE
AXIS...A SURGE OF VERY WARM 850 MB TEMPS NEAR 28 TO 30 DEGREES
CELSIUS HAS CONTINUED TO TRAVERSE NORTHWARD. AT THE SURFACE...A LOW
PRESSURE SYSTEM PUSHING ACROSS THE NORTHERN PLAINS HAS ALLOWED A
TROUGH AXIS TO MOVE THROUGH THE CENTRAL PLAINS.
STRONG BOUNDARY LAYER MIXING AND INCREASED WINDS MAINLY ACROSS THE
SOUTHERN PORTIONS OF THE FORECAST AREA WILL CONTINUE TO ALLOW
TEMPERATURES TO CLIMB THIS AFTERNOON. SEVERAL SITES ACROSS THE ARE
HAVE ALREADY HIT 90 DEGREES AND COULD EASILY INCREASE A FEW MORE
DEGREES. WITH SUCH WARMING TODAY...AND SEVERAL SITES EASILY
REALIZING CONVECTIVE TEMPS...WE COULD SEE SCATTERED CUMULUS DEVELOP
ACROSS THE REGION THIS AFTERNOON AND MAYBE EVEN A THUNDERSTORM OR
TWO. RUC AND LAPS MODELS BOTH INDICATE SOME INSTABILITY ACROSS THE
REGION.
FOR WEDNESDAY...THE SURFACE LOW PRESSURE SYSTEM IS EXPECTED TO SHIFT
JUST NORTHEAST OF THE REGION...DRAGGING A COLD FRONT ACROSS THE
FORECAST AREA. BY AFTERNOON...WINDS ARE EXPECTED TO SHIFT TO THE
NORTHWEST AND EVENTUALLY NORTH. 850 TEMPERATURES LOOK TO REMAIN
QUITE WARM AGAIN ON WEDNESDAY. WITH MODEL SOUNDINGS INDICATING
PLENTY OF BOUNDARY LAYER MIXING...DO NOT SEE A REASON WHY WEDNESDAY
WILL NOT BE AS WARM AS TODAY.
.LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY. FRONTAL BOUNDARY
WHICH PUSHES SOUTH DURING THE DAY WEDNESDAY STALLS ACROSS NORTH
CENTRAL KANSAS WEDNESDAY NIGHT. MODELS...ESPECIALLY THE NAM
INDICATES SOME DECENT MID LEVEL FRONTOGENESIS...BETWEEN H85 AND
H7...ALONG/NORTH OF THE BOUNDARY AFTER MIDNIGHT WEDNESDAY NIGHT WITH
LIFT ALSO ENHANCED AS H7 SHORTWAVE TROUGH LIFTS ACROSS THE CENTRAL
PLAINS. WITH INCREASING LIFT OVERNIGHT WED NIGHT...ADDED IN SOME
LOW POPS.
ON THURSDAY...FRONT RESIDES ACROSS CENTRAL KANSAS TO OUR SOUTH WITH
SURFACE TROUGH/DRYLINE EXTENDING ALONG THE HIGH PLAINS. SREF
INDICATES MUCAPES OF 3000 J/KG ALONG/SOUTH OF THE BOUNDARY WITH 500
TO 1000 OR SO J/KG AHEAD OF DRY LINE ALONG HIGH PLAINS INTO SOUTHERN
NEBRASKA. EFFECTIVE SHEAR PARAMETERS ARE PROGGED BETWEEN 40 AND
50KTS. EASTERLY UPSLOPE FLOW...CONVERGENCE ALONG BOUNDARY AND NEXT
WAVE LIFTING OUT IS EXPECTED TO PROVIDE SUFFICIENT FORCING FOR
CONVECTIVE DEVELOPMENT AND A STRONG TO SEVERE STORM IS POSSIBLE.
OUR WESTERN CWA IS OUTLOOKED IN THE DAY3 FOR SEVERE WEATHER AND THIS
STILL LOOKS REASONABLE BASED ON LATEST MODEL RUNS WITH HAIL/WIND
LOOKING LIKE THE PRIMARY HAZARDS.
LIFT CONTINUES THURSDAY NIGHT AHEAD OF THE UPPER LOW PRESSURE SYSTEM
MOVING OUT OF THE SOUTH CENTRAL ROCKIES. THE ECMWF MAINTAINS A
SLOWER PROGRESSION OF THE SYSTEM THAN OTHER MODELS...AND THE SYSTEM
IS PROGGED TO LIFT ACROSS KANSAS INTO NEBRASKA ON FRIDAY. IT IS
SHAPING UP TO EVOLVE INTO A WIDESPREAD RAINFALL EVENT FROM THURSDAY
NIGHT AND LASTING POTENTIALLY INTO FRIDAY NIGHT WHEN THE SYSTEM
FILLS AND LIFTS TO THE NORTHEAST. INSTABILITY DIMINISHES SO NOT
LOOKING FOR A WHOLE LOT IN THE WAY OF THUNDER BUT SOME DECENT
RAINFALL AMOUNTS ARE POSSIBLE AS PRECIPITABLE WATER VALUES AVERAGE
AROUND AN INCH.
AS WAVE MOVES OFF EARLY IN THE WEEKEND...ANOTHER TROUGH/LOW NOSES
SOUTH ONTO THE PLAINS FM THE NC ROCKIES OVER THE WEEKEND PERIOD.
ALTHOUGH THE WEEKEND ITSELF DOES NOT LOOK LIKE A COMPLETE
RAINOUT...INTERMITTENT CHCS FOR RAINFALL DO EXIST. THE ECMWF
ADVERTISES A COLDER AIRMASS OVER THE WEEKEND COMPARED TO THE GFS
WITH H85 TEMPS DROPPING TO -3 OR -4C IN OUR NORTHERN ZONES...WHILE
THE GFS HAS TRENDED SLIGHTLY WARMER AROUND -2C. WILL KEEP PCPN AS
RAIN SHOWERS UNTIL THESE PERIODS GET CLOSER. CONFIDENCE IS NOT HIGH
REGARDING PCPN CHCS HEADING INTO NEXT WEEK BUT CANNOT ARGUE WITH
ENSEMBLE FORECAST ATTM. TROUGH AXIS LOOKS TO DEPART AROUND THE
TUESDAY TIME FRAME...WITH HEIGHT RISES/MODERATING TEMPS BEHIND THE
SYSTEM.
FOR TEMPS...AFTER HOT CONDITIONS WEDNESDAY...THURSDAY WILL BE COOLER
WITH A FAIRLY SHARP TEMP GRADIENT IN MAX TEMPS N/S...WARMING NEAR
THE FRONTAL ZONE. TEMPS WILL LIKELY STRUGGLE FRIDAY IN
CLOUDS/PCPN...THEN THE COLD AIRMASS SETTLES IN OVER THE WEEKEND.
50S LOOK TO HOLD SAT/SUN INTO MONDAY FOR HIGHS BEFORE AIRMASS MODERATES
TUESDAY. WILL NEED TO CONTINUE TO MONITOR LOW TEMPS FOR
FROST/FREEZE POTENTIAL.
&&
.PREV DISCUSSION... /ISSUED 125 PM CDT TUE APR 24 2012/
AVIATION...18Z KGRI TAF UPDATE. VFR CONDITIONS WILL CONTINUE THROUGHOUT
THE TAF PERIOD. ALTHOUGH STRONGER WIND GUSTS WERE OCCURRING THIS
MORNING...THE MAIN TROUGH AXIS HAS BEGUN TO SHIFT ACROSS THE
REGION. AS A RESULT...WINDS HAVE DECREASED TO LIGHT AND VARIABLE
ACROSS THE REGION. WITH THE WARMER TEMPERATURES THIS
AFTERNOON...A FEW CUMULUS CLOUDS COULD DEVELOP ACROSS THE REGION
AND POSSIBLY SPAN A SHOWER OR THUNDERSTORM. AT THIS TIME...EXPECT
ANY STORMS TO BE ISOLATED IN NATURE. BY THIS EVENING...WINDS WILL
BECOME LIGHT AND VARIABLE.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM/AVIATION...SALTZMAN
LONG TERM...FAY
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
552 PM CDT TUE APR 24 2012
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND WEDNESDAY.
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW SURFACE LOW
PRESSURE SITUATED OVER SE SASKATCHEWAN EARLY THIS AFTERNOON...AND
WARM FRONT STRETCHING SOUTHEAST OVER THE NORTHERN PLAINS. WISCONSIN
STILL RESIDES WITHIN CYCLONIC AND NORTHERLY FLOW AROUND A DEEP LOW
PRESSURE SYSTEM OVER QUEBEC. MID-LEVEL MOISTURE...DIURNAL
HEATING...AND DEEP MIXING HAS CONTRIBUTED TO A WIDESPREAD CU FIELD
OVER NE WISCONSIN. TEMPS HAVE WARMED QUICKLY TODAY INTO THE 60S
EXCEPT NEAR LAKE MICHIGAN AND OVER FAR NORTHERN WISCONSIN. AS LOW
PRESSURE MOVE SE FROM THE NORTHERN PLAINS INTO ILLINOIS TONIGHT INTO
WEDNESDAY...PRECIP CHANCES ARE THE MAIN FORECAST CONCERN.
TONIGHT...LOW PRESSURE OVER SE SASKATCHEWAN WILL SLIDE SE ALONG A
BAROCLINIC ZONE STRETCHING FROM THE NORTHERN PLAINS TO THE OHIO
VALLEY. FGEN NORTH OF THIS BAROCLINIC ZONE OVER SASKATCHEWAN AND
MANITOBA WILL SLIDE SE AS WELL INTO THE NORTHERN MISSISSIPPI VALLEY
BY 12Z WEDNESDAY. THOUGH CLOUDS WILL BE INCREASING AHEAD OF THE
FGEN BAND LATE TONIGHT...AND LOWERING AS WELL...AM COUNTING ON DRY
SE FLOW IN THE LOW LEVELS TO KEEP PRECIP WEST OF THE REGION
TONIGHT. INHERITED LOW CHANCE POPS OVER NORTH-CENTRAL
WISCONSIN...AND WILL KEEP THEM JUST IN CASE SHOWERS BECOME A TAD
MORE AMBITIOUS THAN THE CURRENT THINKING. TEMPERATURES RANGING FROM
THE MID 30S NORTH TO LOW 40S SOUTH.
WEDNESDAY...MODELS HAVE COME INTO BETTER AGREEMENT TRACKING THE
SURFACE LOW PRESSURE FROM SW MINNESOTA TO NORTHWEST ILLINOIS BY 00Z
THU. THE TIGHTER BAROCLINIC ZONE UPSTREAM WILL SHIFT EAST INTO SW
WISCONSIN...WITH MID-LEVEL FGEN AND UPPER DIVERGENCE INCREASING
ACROSS THE AREA DURING THE MORNING...THEN PASSING ACROSS THE AREA
DURING THE AFTERNOON. THIS SHOULD LEAD TO A PRETTY GOOD SWATH OF
SHOWERS THROUGH THE DAY OVER CENTRAL WISCONSIN WHERE THE BEST
FORCING WILL RESIDE...THOUGH ALL AREAS STAND TO GET SOME RAIN. WILL
INCREASE POPS AND QPF. CLOUDS...RAIN...AND SE FLOW WILL LEAD TO A
CONSIDERABLY COOLER DAY. HAVE SIDED WITH THE COOLER GUIDANCE
WHICH PLACES HIGHS IN THE MID 50S NORTH TO NEAR 60 SOUTH.
.LONG TERM...WEDNESDAY NIGHT THROUGH NEXT TUESDAY...MAIN FCST
CONCERNS ARE PCPN TRENDS WEDS NGT...POTENTIAL FOR MORE HARD
FREEZES LATE IN THE WEEK...THEN WHETHER OR NOT TO KEEP SMALL
POPS IN THE FCST FOR THE WEEKEND.
ISENT LIFT AND ASSOCIATED SHOWERS WILL BE ONGOING EARLY WEDS
EVENING...IN ADVANCE OF A COLD FRONT. IN ADDITION...A SHORT-WAVE
TROF IS EXPECTED TO BRUSH PAST NE WI DURING THE NIGHT. HAVE RAISED
POPS TO LIKELY OVER FAR NE WI FOR THE EVG HOURS...THEN CONTINUED
THE TREND OF DECREASING SHOWERS FOR THE OVERNIGHT PERIOD.
CANADIAN HIGH PRESSURE WILL BUILD INTO THE REGION IN THE WAKE OF
THE COLD FRONT ON THURSDAY AND FRIDAY...BRINGING DRY AND COOLER
CONDITIONS. SUB-FREEZING TEMPERATURES APPEAR LIKELY OVER NEARLY ALL
OF THE CWA ON THURSDAY NIGHT. LOWERED MIN TEMPS OVER THE ENTIRE
AREA...WITH READINGS AS LOW AS 20 IN THE TYPICAL COLD SPOTS IN NC
WI. WOULD NOT BE SURPRISED IF A FEW LOCATIONS GET INTO THE TEENS.
MODELS HAVE TRENDED FARTHER SOUTH WITH LOW PRESSURE MOVG THROUGH
THE UPPER MIDWEST OVER THE WEEKEND...AND KEEP C/NE WI ENTRENCHED
IN DRY AIR FEEDING OUT OF THE MASSIVE CANADIAN HIGH. HAVE REMOVED
ALL PCPN FROM THE WEEKEND FCST...AND DON`T BRING ANY RAIN BACK
INTO THE FCST UNTIL THE CANADIAN HIGH SHIFTS EAST MONDAY NIGHT
INTO TUESDAY. THIS WILL MEAN THAT THERE WILL BE CONTINUED
POTENTIAL FOR FREEZING NIGHTTIME TEMPERATURES DURING THIS
PERIOD...SO THOSE WITH AGRICULTURAL CONCERNS SHOULD STAY TUNED TO
THE LATEST FCSTS.
&&
.AVIATION...MID LEVEL VFR CIGS WILL INCREASE FROM THE NORTH
OVERNIGHT. CIGS WILL LOWER TO AROUND 4000 TO 5000 FT LEVELS ON
WEDNESDAY AS RAIN SPREADS OVER THE AREA.
TDH
&&
.FIRE WEATHER...ALTHOUGH SHOWER ACTIVITY WILL RESULT IN A BRIEF
REPRIEVE FROM THE LOW HUMIDITY ON WEDNESDAY...A LARGE CANADIAN
HIGH PRESSURE SYSTEM WILL RETURN TO THE REGION ON THURSDAY...
AND REMAIN OVER THE AREA THROUGH ABOUT NEXT MONDAY. WITH VERY DRY
AIR ENTRENCHED OVER THE REGION...HUMIDITY READINGS WILL LIKELY
DROP TO NEAR CRITICAL LEVELS AGAIN FOR THE END OF THE WORK WEEK
AND THE WEEKEND.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
239 PM CDT TUE APR 24 2012
.SHORT TERM...TONIGHT AND WEDNESDAY.
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW SURFACE LOW
PRESSURE SITUATED OVER SE SASKATCHEWAN EARLY THIS AFTERNOON...AND
WARM FRONT STRETCHING SOUTHEAST OVER THE NORTHERN PLAINS. WISCONSIN
STILL RESIDES WITHIN CYCLONIC AND NORTHERLY FLOW AROUND A DEEP LOW
PRESSURE SYSTEM OVER QUEBEC. MID-LEVEL MOISTURE...DIURNAL
HEATING...AND DEEP MIXING HAS CONTRIBUTED TO A WIDESPREAD CU FIELD
OVER NE WISCONSIN. TEMPS HAVE WARMED QUICKLY TODAY INTO THE 60S
EXCEPT NEAR LAKE MICHIGAN AND OVER FAR NORTHERN WISCONSIN. AS LOW
PRESSURE MOVE SE FROM THE NORTHERN PLAINS INTO ILLINOIS TONIGHT INTO
WEDNESDAY...PRECIP CHANCES ARE THE MAIN FORECAST CONCERN.
TONIGHT...LOW PRESSURE OVER SE SASKATCHEWAN WILL SLIDE SE ALONG A
BAROCLINIC ZONE STRETCHING FROM THE NORTHERN PLAINS TO THE OHIO
VALLEY. FGEN NORTH OF THIS BAROCLINIC ZONE OVER SASKATCHEWAN AND
MANITOBA WILL SLIDE SE AS WELL INTO THE NORTHERN MISSISSIPPI VALLEY
BY 12Z WEDNESDAY. THOUGH CLOUDS WILL BE INCREASING AHEAD OF THE
FGEN BAND LATE TONIGHT...AND LOWERING AS WELL...AM COUNTING ON DRY
SE FLOW IN THE LOW LEVELS TO KEEP PRECIP WEST OF THE REGION
TONIGHT. INHERITED LOW CHANCE POPS OVER NORTH-CENTRAL
WISCONSIN...AND WILL KEEP THEM JUST IN CASE SHOWERS BECOME A TAD
MORE AMBITIOUS THAN THE CURRENT THINKING. TEMPERATURES RANGING FROM
THE MID 30S NORTH TO LOW 40S SOUTH.
WEDNESDAY...MODELS HAVE COME INTO BETTER AGREEMENT TRACKING THE
SURFACE LOW PRESSURE FROM SW MINNESOTA TO NORTHWEST ILLINOIS BY 00Z
THU. THE TIGHTER BAROCLINIC ZONE UPSTREAM WILL SHIFT EAST INTO SW
WISCONSIN...WITH MID-LEVEL FGEN AND UPPER DIVERGENCE INCREASING
ACROSS THE AREA DURING THE MORNING...THEN PASSING ACROSS THE AREA
DURING THE AFTERNOON. THIS SHOULD LEAD TO A PRETTY GOOD SWATH OF
SHOWERS THROUGH THE DAY OVER CENTRAL WISCONSIN WHERE THE BEST
FORCING WILL RESIDE...THOUGH ALL AREAS STAND TO GET SOME RAIN. WILL
INCREASE POPS AND QPF. CLOUDS...RAIN...AND SE FLOW WILL LEAD TO A
CONSIDERABLY COOLER DAY. HAVE SIDED WITH THE COOLER GUIDANCE
WHICH PLACES HIGHS IN THE MID 50S NORTH TO NEAR 60 SOUTH.
.LONG TERM...WEDNESDAY NIGHT THROUGH NEXT TUESDAY...MAIN FCST
CONCERNS ARE PCPN TRENDS WEDS NGT...POTENTIAL FOR MORE HARD
FREEZES LATE IN THE WEEK...THEN WHETHER OR NOT TO KEEP SMALL
POPS IN THE FCST FOR THE WEEKEND.
ISENT LIFT AND ASSOCIATED SHOWERS WILL BE ONGOING EARLY WEDS
EVENING...IN ADVANCE OF A COLD FRONT. IN ADDITION...A SHORT-WAVE
TROF IS EXPECTED TO BRUSH PAST NE WI DURING THE NIGHT. HAVE RAISED
POPS TO LIKELY OVER FAR NE WI FOR THE EVG HOURS...THEN CONTINUED
THE TREND OF DECREASING SHOWERS FOR THE OVERNIGHT PERIOD.
CANADIAN HIGH PRESSURE WILL BUILD INTO THE REGION IN THE WAKE OF
THE COLD FRONT ON THURSDAY AND FRIDAY...BRINGING DRY AND COOLER
CONDITIONS. SUB-FREEZING TEMPERATURES APPEAR LIKELY OVER NEARLY ALL
OF THE CWA ON THURSDAY NIGHT. LOWERED MIN TEMPS OVER THE ENTIRE
AREA...WITH READINGS AS LOW AS 20 IN THE TYPICAL COLD SPOTS IN NC
WI. WOULD NOT BE SURPRISED IF A FEW LOCATIONS GET INTO THE TEENS.
MODELS HAVE TRENDED FARTHER SOUTH WITH LOW PRESSURE MOVG THROUGH
THE UPPER MIDWEST OVER THE WEEKEND...AND KEEP C/NE WI ENTRENCHED
IN DRY AIR FEEDING OUT OF THE MASSIVE CANADIAN HIGH. HAVE REMOVED
ALL PCPN FROM THE WEEKEND FCST...AND DON`T BRING ANY RAIN BACK
INTO THE FCST UNTIL THE CANADIAN HIGH SHIFTS EAST MONDAY NIGHT
INTO TUESDAY. THIS WILL MEAN THAT THERE WILL BE CONTINUED
POTENTIAL FOR FREEZING NIGHTTIME TEMPERATURES DURING THIS
PERIOD...SO THOSE WITH AGRICULTURAL CONCERNS SHOULD STAY TUNED TO
THE LATEST FCSTS.
&&
.AVIATION...SCT TO BKN MID DECK OVER EASTERN WISCONSIN THIS
AFTERNOON AS DEEP MIXING GENERATES DIURNAL CU. CLOUDS WILL BE ON
THE INCREASE AND LOWER THROUGH THE NIGHT AS A STORM SYSTEM OVER
THE NORTHERN PLAINS MOVES SOUTHEAST INTO THE NORTHERN MISSISSIPPI
VALLEY. SHOWERS FROM THE WEST WILL PUSH ACROSS THE AREA DURING THE
MORNING HOURS AS SOUTHEAST WINDS DEVELOP. HAVE LEFT CONDITIONS VFR
AS DRY AIR WILL LIKELY ERODE CLOUD COVER AND PRECIP AS THEY
ARRIVE. CONDITIONS TO FALL TO MVFR TOMORROW AFTERNOON ONCE THE LOW
LEVELS MOISTEN.
MPC
&&
.FIRE WEATHER...ALTHOUGH SHOWER ACTIVITY WILL RESULT IN A BRIEF
REPRIEVE FROM THE LOW HUMIDITY ON WEDNESDAY...A LARGE CANADIAN
HIGH PRESSURE SYSTEM WILL RETURN TO THE REGION ON THURSDAY...
AND REMAIN OVER THE AREA THROUGH ABOUT NEXT MONDAY. WITH VERY DRY
AIR ENTRENCHED OVER THE REGION...HUMIDITY READINGS WILL LIKELY
DROP TO NEAR CRITICAL LEVELS AGAIN FOR THE END OF THE WORK WEEK
AND THE WEEKEND.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MPC/KIECKBUSCH