Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 04/04/13
AREA FORECAST DISCUSSION
NWS PUEBLO CO
905 PM MDT WED APR 3 2013
.UPDATE...
ISSUED AT 905 PM MDT WED APR 3 2013
CURRENT WATER VAPOR IMAGERY INDICATING AN EMBEDDED SHORT WAVE
TRANSLATING ACROSS SOUTH CENTRAL WYOMING AND INTO NORTH CENTRAL
COLORADO AT THIS TIME. REGIONAL RADARS INDICATING SHOWERS ALONG
WITH A FEW LIGHTNING STRIKES ASSOCIATED WITH THIS SYSTEM MOVING
ACROSS NORTHERN COLORADO AT THIS TIME. LATEST NAM AND RAP HAVE
SHOWERS DIMINISHING AS THEY CONTINUE TO MOVE SOUTH AND EAST WITH
ONLY INCREASING MID AND AND HIGH LEVEL CLOUDS ACROSS SOUTH CENTRAL
AND SOUTHEAST COLORADO. HOWEVER...THE LAST FEW RUNS OF THE HRRR
IS INDICATING A FEW SHOWERS MOVING OUT ACROSS THE FRONT RANGE AND
INTO NORTHERN AND EASTERN PORTIONS OF EL PASO COUNTY AFTER
MIDNIGHT. HAVE NOT BOUGHT OFF ON THIS SCENARIO WITH SHOWERS
SEEMINGLY DIMINISHING WITH THE LOSS OF HEATING...THOUGH WILL NEED
TO MONITOR LATEST HRRR TRENDS.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 313 PM MDT WED APR 3 2013
CURRENTLY...
SKIES CLEARING PRETTY QUICKLY FROM NW TO SE ACROSS THE REGION. ONLY
AREA OF CONSIDERABLE CLOUDINESS AT 2 PM WAS OVER THE FAR SE PLAINS.
Q WAS BUBBLING OVER THE S MTNS. TEMPS WERE IN THE 40S OVER THE
PLAINS WHERE THERE WAS SUN...AND 30S WHERE IT WAS CLOUDY. THE SLV
WAS IN THE 50S.
REST OF TODAY INTO TONIGHT...
RIDGING WILL BUILD OVER THE FCST AREA AND SKIES WILL CONTINUE TO
CLEAR. A FEW CONVECTIVE SHOWERS WILL BE POSSIBLE OVER THE SAN JUANS
AND S MTNS THE REST OF THIS AFTERNOON AND EARLY EVENING. OTHERWISE
EXPECT CLEARING SKIES.
THE ONLY CONCERN I HAVE FOR TONIGHT WILL BE PATCHY GROUND FOG IN
PLACES. BASED ON CURRENT RH PROGS...BEST CHANCE FOR SOME FOG WILL BE
OVER THE FAR E PLAINS...MAINLY ALONG THE ARK RVR. TEMPS TONIGHT WILL
BE COOL WITH U20S TO L30S ACROSS THE PLAINS...AND 20S VALLEYS.
THURSDAY...
500 MB RIDGE AXIS WILL BE OVER THE STATE BY LATE AFTERNOON.
TEMP-WISE...TOMORROW WILL BE QUITE A NICE DAY WITH HIGHS IN THE L70S
MOST OF THE PLAINS WITH 60S IN THE VALLEYS. SKIES WILL BE MOSTLY
SUNNY. NO PRECIP IS EXPECTED.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 313 PM MDT WED APR 3 2013
SOME ADJUSTMENTS NEEDED DURING THE LONGER TERM WITH MAIN
METEOROLOGICAL ISSUES CONTINUING TO BE TEMPERATURES...GUSTY WINDS
AT TIMES...ELEVATED FIRE WEATHER CONCERNS FROM FRIDAY AFTERNOON
INTO FRIDAY EVENING...THUNDERSTORM THREAT OVER PORTIONS OF THE FAR
EASTERN PLAINS...ESPECIALLY FROM SUNDAY EVENING INTO SUNDAY NIGHT
AND FINALLY THE IMPACT THAT UPPER SYSTEM WILL PRODUCE OVER THE
FORECAST DISTRICT EARLY NEXT WEEK.
IT STILL APPEARS THE RELATIVELY BENIGN AND MILD TO WARM
METEOROLOGICAL CONDITIONS SHOULD BE NOTED OVER THE CWFA INTO
FRIDAY...THANKS TO A TRANSITORY UPPER RIDGE MOVING ACROSS THE AREA.
IN ADDITION...ELEVATED FIRE CONCERNS ARE STILL ANTICIPATED FROM
FRIDAY AFTERNOON INTO FRIDAY EVENING...ESPECIALLY OVER PORTIONS OF
FIRE WEATHER ZONES 222/224/225/228>233 AND 235 DUE TO PROJECTED
LOW MINIMUM RELATIVE HUMIDITIES AND GUSTY WINDS AT TIMES.
AS TOUCHED UPON IN PREVIOUS DISCUSSIONS...UPPER LEVEL
DISTURBANCES...IMPACTING PRIMARILY NORTHERN PORTIONS OF THE FORECAST
DISTRICT WITH INCREASED PRECIPITATION CHANCES ARE PROJECTED TO
IMPACT THE CWFA FROM LATER FRIDAY INTO THE WEEKEND...ALLOWING FOR
SOMEWHAT COOLER TEMPERATURES AS WELL AS GUSTY WINDS AT TIMES. IN
ADDITION...INCREASED THUNDERSTORM CHANCES MAY BE NOTED OVER FAR
EASTERN PORTIONS OF THE FORECAST DISTRICT FROM SUNDAY EVENING INTO
SUNDAY NIGHT AS DEEPER ATMOSPHERIC MOISTURE INTERACTS WITH
RELATIVELY HEALTHY 0 TO 6 KM BULK SHEARS.
UPPER TROUGH SHOULD THEN IMPACT THE FORECAST DISTRICT BY EARLY NEXT
WEEK WITH THE HIGHEST POTENTIAL FOR WIDESPREAD PRECIPITATION
PROJECTED FROM LATER MONDAY INTO AT LEAST TUESDAY NIGHT. HAVE PAINTED
GENERALLY SCATTERED POPS DURING THIS TIME-FRAME WITH A POTENTIAL
FOR HEALTHY ACCUMULATING SNOW...ESPECIALLY OVER HIGHER TERRAIN
AREAS. WFO PUEBLO WILL CONTINUE TO MONITOR CLOSELY.
GUSTY WINDS WILL BE POSSIBLE FROM FRIDAY INTO FRIDAY NIGHT AND THEN
AGAIN FROM NEXT TUESDAY INTO TUESDAY NIGHT. WARMEST TEMPERATURES OF
THE LONGER TERM ARE EXPECTED FRIDAY WHILE COOLEST CONDITIONS ARE
ANTICIPATED BY NEXT TUESDAY AND WEDNESDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 313 PM MDT WED APR 3 2013
VFR CONDITIONS ARE EXPECTED THE NEXT 24H AT ALL 3 TAF
SITES...KPUB...KALS AND KCOS. THE ONLY CONCERN I HAVE AT EACH OF
THESE SITES IS SOME PATCHY GROUND FOG DEVELOPING LATE TONIGHT/EARLY
TOMORROW MORNING...HOWEVER PROBABILITY OF IT OCCURRING APPEARS TOO LOW TO
MENTION EXPLICITLY IN THE TAF PRODUCT.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...MW
SHORT TERM...HODANISH
LONG TERM...77
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1059 AM MDT TUE APR 2 2013
.UPDATE...
&&
.SHORT TERM...MOST IF NOT ALL OF CWA HAS BEEN UNDER AN AREA OF
DRIER AIR AHEAD OF THE MAIN UPPER LOW OVER EASTERN UTAH. SOME
CLEARING NOTED EARLIER ACROSS SUMMIT COUNTY. LATEST MODELS DO HAVE
THE MOISTURE INCREASING AND PRECIP REDEVELOPING BY THE AFTERNOON.
BEGINNING TO SEE SOME CLOUD ENHANCEMENT ACROSS MOUNTAINS AND ALONG
FOOTHILLS. BASED ON CURRENT CONDITIONS...BACKED OFF ON PRECIP
CHANCES ACROSS MOUNTAINS...FOOTHILLS AND VALLEYS THIS MORNING. AS
FOR PLAINS...DROPPED THE MENTION OF THE PRECIP THROUGH 18Z MOST
AREAS EXCEPT NEAR THE FOOTHILLS AND WYOMING BORDER. KEPT SOME LOW
POPS ALONG THE PALMER DIVIDE AS WELL. BY AFTERNOON...INCREASING
MOISTURE AND INSTABILITY ALONG WITH LIFT WILL ALL COMBINE TO
INCREASE THE PRECIP CHANCES. LATEST RAP INCREASES THE EASTERLY
FLOW AFTER 21Z...PROVIDING UPSLOPE. OVERALL...CURRENT FORECASTS FOR
THIS AFTERNOON AND EVENING SEEM REASONABLE. WILL BOOST THE
FOOTHILLS POPS A BIT AFTER 21Z THROUGH THE EVENING. SNOW LEVELS
BETWEEN 5 AND 7 THOUSAND FEET THIS AFTERNOON STILL SEEMS
REASONABLE...LOWERING TO 4 TO 6 THOUSAND FEET TONIGHT. OVERALL...
PRECIP WILL GENERALLY BE LIGHT. THERE MAY BE SOME AREAS WHERE
SHOWERS COULD BE HEAVIER...PERHAPS IN EAST FACING SLOPES.
.AVIATION...EARLIER CLEARING HAD FILLED IN AS LOCAL MESOCYCLONE
BROUGHT MVFR CEILINGS TO THE AREA AIRPORTS. STILL EXPECTING
CEILINGS TO IMPROVE A BIT AROUND 18Z...THEN LOWER AGAIN AFTER 21Z
AS RAIN SHOWERS DEVELOP. SOME SNOW WILL MIX WITH THE RAIN BY 00Z.
AREAS OF MVFR/IFR CONDITIONS POSSIBLE WITH THE HEAVIER SHOWERS
FROM 21Z THROUGH 06Z...THEN A GRADUAL IMPROVEMENT OVERNIGHT.
INSTRUMENT APPROACHES LIKELY FOR MOST OF THE TIME.
&&
.PREV DISCUSSION... /ISSUED 451 AM MDT TUE APR 2 2013/
SHORT TERM...UPPER LOW OVER UTAH WILL MOVE SLOWLY ESE TOWARD
SOUTHEAST COLORADO BY WEDNESDAY MORNING. MEANWHILE MOIST SOUTH TO
SOUTHEAST LOW LEVEL FLOW WILL CONTINUE OVER THE PLAINS. AIRMASS
WILL REMAIN SLIGHTLY UNSTABLE...WITH SOME LOW LEVEL STABILITY OVER
THE PLAINS THIS MORNING AS THERE IS SOME WARM ADVECTION OFF THE
GROUND...AND THEN SLIGHT COOLING ALOFT THIS EVENING AS THE COLD
POOL WITH THE LOW MOVES OVER. WITH THE DRIER AIR ALOFT THERE IS
NOT MUCH TO PRODUCE SIGNIFICANT SHOWERS THIS MORNING...THOUGH WEAK
CONVERGENCE AND LIFT IN THE MOIST LOWER LEVELS COULD PRODUCE SOME
DRIZZLE OR SHALLOW SHOWER ACTIVITY. CONVECTION ON THE EDGE OF THE
COLD POOL COULD ALSO CLIP THE NORTHERN MOUNTAINS. EXPECT SHOWERS
TO BREAK OUT THIS AFTERNOON AS BEST LIFT...SLIGHT COOLING...AND
LOW LEVEL CONVERGENCE ALL INCREASE. BEST TIME WILL LIKELY BE IN
THE LATE AFTERNOON AND EARLY EVENING AS THE LOW SLIDES SOUTH OF
OUR AREA AND WITH A LITTLE HELP FROM DIURNAL HEATING. I LOWERED
POPS A LITTLE THIS MORNING...AND RAISED THEM MAINLY FOR THE
MOUNTAINS THIS AFTERNOON AND EVENING. AMOUNTS WILL GENERALLY BE
LIGHT THOUGH IF THERE COULD BE SOME ORGANIZATION THE FOCUSED
CONVECTION COULD PRODUCE HEAVIER AMOUNTS. TWO POSSIBILITIES FOR
THIS...SLOW MOVING SHOWERS OVER THE CREST OR EAST SLOPES OF THE
FRONT RANGE COULD PRODUCE SUSTAINED MODERATE TO HEAVY SNOW FOR
SEVERAL HOURS. ALSO MODELS HAVE BEEN PRODUCING NARROW SNOW BANDS
ON THE PLAINS IN THE DEFORMATION ZONE ON THE NORTH SIDE OF THE
LOW WITH UP TO 6 INCHES OF SNOW...BUT IN DIFFERENT PLACES. THIS IS
CERTAINLY POSSIBLE THOUGH THE DEFORMATION ZONE WILL LIKELY BE
SINKING SOUTHWARD WHICH SHOULD SPREAD THAT BAND OUT A BIT.
TEMPERATURES WILL ALSO BE RATHER WARM...SO FAR WE HAVE BEEN A BIT
WARMER THAN THE MODELS SHOW. EXPECTING SNOW LEVELS BETWEEN 5 AND 7
THOUSAND FEET TODAY AND 4 TO 6 THOUSAND FEET TONIGHT. WE MAY YET
NEED TO RAISE POPS FOR A BETTER CHANCE OF LIGHT PRECIPITATION AT
THE PEAK OF THIS LATE TODAY...BUT OVERALL PRECIPITATION WILL
GENERALLY BE LIGHT WITH WARM TEMPERATURES. SOME TRAVEL IMPACT
POSSIBLE UNDER HEAVIER SHOWERS...BUT EXPECT COVERAGE OF THAT TO BE
LOCALIZED. SYSTEM WILL SINK SOUTH LATER TONIGHT AND WE SHOULD SEE
SOME CLEARING IN THE NORTH BY MORNING.
LONG TERM...MODELS HAVE THE UPPER LOW OVER SOUTHEASTERN
COLORADO/NORTH CENTRAL NEW MEXICO AT 12Z WEDNESDAY MORNING. BY
12Z THURSDAY MORNING...IT IS WELL EAST OF THE CWA WITH
NORTHWESTERLY FLOW ALOFT IN PLACE HERE. BY THURSDAY NIGHT...AN
ADVANCING UPPER RIDGE`S AXIS IS OVER THE CWA. THE FLOW ALOFT IS
WESTERLY AND FAIRLY LIGHT. THE QG VERTICAL VELOCITY FIELDS SHOW
WEAK DOWNWARD SYNOPTIC SCALE ENERGY FOR THE FORECAST AREA
WEDNESDAY THROUGH THURSDAY EVENING. THE BOUNDARY LAYER FLOW LOOKS
TO ADHERE TO NORMAL DUIRNAL PATTERNS ALL FOUR PERIODS WITH A
FAIRLY WEAK PRESSURE GRADIENT PROGGED. FOR MOISTURE...THERE IS
SOME LINGERING ON WEDNESDAY...BUT IT DECREASES THROUGH THE DAY. IT
IS PRETTY DRY WEDNESDAY NIGHT. THERE IS SOME MID AND UPPER LEVEL
MOISTURE AROUND THURSDAY AND THURSDAY...WITH THE GFS SHOWING A
LOT IN THE UPPER LEVELS AFTER 06Z FRIDAY MORNING EARLY. THERE IS A
BIT OF CAPE PROGGED OVER THE MOUNTIANS AND FOOTHILLS ON THE NAM
ONLY FOR LATE DAY WEDNESDAY. THERE IS A TAD OF MEASURABLE
PRECIPITATION ON THE QPF FIELDS LATE DAY WEDNESDAY...OTHERWISE
NOTHING THROUGH THE PERIODS. WILL GO WITH 20-30%S IN THE MOUNTAINS
ON WEDNESDAY. OTHERWISE NO POPS ANYWHERE FOR THE REST OF THE
PERIODS. FOR TEMPERATURES...WEDNESDAY`S HIGHS ARE 3-6 C WARMER
THAN TUESDAY`S. THURSDAY`S HIGHS ARE 3-5 C WARMER THAN
THURSDAY`S. FOR THE LATER DAYS...FRIDAY THROUGH MONDAY...MODELS
HAVE A WEAK UPPER TROUGH TO MOVE ACROSS FRIDAY AFTERNOON AND
EVENING. ON SATURDAY INTO SUNDAY...FAIRLY STRONG WESTERLY FLOW
ALOFT IS PROGGED...WITH UPPER TROUHGING SUNDAY NIGHT THROUGH
MONDAY NIGHT. MOISTURE INCREASES ON FRIDAY AND THERE IS QUITE A
BIT AROUND LATE SUNDAY THROUGH MONDAY NIGHT.
AVIATION...EXPECT SCATTERED RAIN SHOWERS TO DEVELOP THIS
AFTERNOON AND CONTINUE THIS EVENING...MIXING WITH OR CHANGING TO
SNOW AFTER DARK. TEMPERATURES SHOULD STAY AT OR ABOVE FREEZING
WHICH WILL LIMIT SNOW ACCUMULATION. MVFR CONDITIONS WILL GRADUALLY
LIFT THIS MORNING...THEN CEILINGS WILL LOWER AGAIN AS THE SHOWERS
DEVELOP LATE TODAY WITH AREAS OF MVFR CEILINGS/VISIBILITIES AND
IFR CONDITIONS POSSIBLE IN THE HEAVIER SHOWERS FROM 21Z TO
06Z...THEN IMPROVING CONDITIONS AGAIN. INSTRUMENT APPROACHES TO
KDEN WILL LIKELY BE NEEDED MOST OF THE TIME THROUGH THIS EVENING.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...D-L
LONG TERM....RJK
AVIATION...D-L
AREA FORECAST DISCUSSION
NWS MIAMI FL
1015 AM EDT TUE APR 2 2013
.UPDATE...
THE LATEST VISIBLE SATELLITE IMAGERY SHOWED THE LARGE STRATUS DECK
OVER MUCH OF THE INTERIOR SECTIONS CLEARING AND BURNING OFF AS OF
9-10AM. THIS CLEARING TREND WILL CONTINUE THROUGH THE LATE
MORNING HOURS WITH MOSTLY SUNNY SKIES EXPECTED THROUGH THE EARLY
AFTERNOON. THE LATEST OBSERVATIONS AROUND THE AREA INDICATED
VISIBILITIES HAVE IMPROVED SIGNIFICANTLY WITH NO RESTRICTIONS DUE
TO FOG. HOWEVER...SMOKE FROM THE WILDFIRE IN COLLIER COUNTY WILL
CONTINUE TO IMPACT SOME OF THE AREAS...WHICH INCLUDES I75 MOSTLY
IN COLLIER COUNTY WHERE A FEW AREAS OF THE HIGHWAY REMAIN CLOSED.
ELSEWHERE...ANOTHER PLEASANT DAY IS EXPECTED WITH HIGHS FORECAST
TO REACH THE LOWER 80S ALONG THE COAST TO THE MID TO UPPER 80S
FARTHER INLAND. LOW-LEVEL FLOW WILL QUICKLY SHIFT TO THE NORTH
AND NORTHEAST THROUGH THE AFTERNOON...WHICH SHOULD ALLOW FOR SOME
INCREASE IN LOW-LEVEL MOISTURE. THIS INCREASE IN MOISTURE COMBINED
WITH THE DAYTIME HEATING SHOULD INDUCE A LOW-LOW CU FIELD ACROSS
THE INTERIOR LOCATIONS AND POSSIBLY A FEW SHOWERS THROUGH THE LATE
AFTERNOON HOURS AS THE WEST COAST SEA BREEZE PUSHES INLAND.
&&
.PREV DISCUSSION... /ISSUED 745 AM EDT TUE APR 2 2013/
UPDATE...
FOR THE SHORT TERM...DENSE FOG CONTINUES TO AFFECT MOST OF THE
SOUTH FLORIDA PENINSULA. THE ONLY TERMINALS NOT CURRENTLY AFFECTED
WITH IFR VISIBILITY RESTRICTIONS ARE KMIA AND KOPF...BUT THESE
TERMINALS COULD EXPERIENCE BRIEF PERIODS OF MIST AND/OR FOG OVER
THE NEXT HOUR OR SO WITH SUB-VFR VIS RESTRICTIONS AND WILL AMEND AS
NECESSARY. OTHERWISE...BY MID MORNING AND THROUGH THE AFTERNOON
MAINLY VFR CONDITIONS EXPECTED ALL TERMINALS. WITH LIGHT VARIABLE
FLOW THIS MORNING...THE WEST AND EAST COAST SEA BREEZES ARE
EXPECTED TO FORM TODAY.
60
PREV DISCUSSION... /ISSUED 647 AM EDT TUE APR 2 2013/
UPDATE...
SHORT TERM MODELS CONTINUE TO INDICATE THE POSSIBILITY OF AN
AFTERNOON SHOWER IN THE INTERIOR PORTION OF THE STATE LATER THIS
AFTERNOON. THE MAIN FOCUS WILL BE THE CONVERGENCE OF THE SEA
BREEZE. CONFIDENCE IS STILL LOW, BUT FEEL THERE IS ENOUGH OF A
CHANCE TO PUT A MENTION IN THE FORECAST FOR TODAY.
PREV DISCUSSION... /ISSUED 447 AM EDT TUE APR 2 2013/
DISCUSSION...
THE WEATHER FOR THE MOST PART IS QUIET. THERE IS SOME DENSE FOG IN
THE WESTERN HALF OF THE FORECAST AREA, AND SOME LOCALIZED FOG NEAR
TAMIAMI. SO, A DENSE FOG ADVISORY IS IN PLACE FOR PORTIONS OF
SOUTH FLORIDA. THIS FOG SHOULD BURN OFF WITHIN A COUPLE OF HOURS
AFTER SUNRISE.
OTHERWISE, HIGH PRESSURE IS BUILDING IN TODAY. AREAS IN THE
INTERIOR PORTIONS OF THE STATE WILL SEE HIGH TEMPERATURES IN THE
MID TO UPPER 90S. COASTAL AREAS WILL SEE HIGHS IN THE LOW TO MID
80S. THERE SHOULD BE A DECENT SEA BREEZE TO DEVELOP TODAY. WITH
SOME MOISTURE, WILL HAVE TO WATCH FOR INDICATIONS THAT SOME
SHOWERS MAY DEVELOP IN THE INTERIOR, ESPECIALLY IF THERE IS ANY
SEA BREEZE CONVERGENCE. NAM MODEL SOUNDINGS ARE SHOWING A GOOD CAP
BETWEEN 500 AND 600 MB. THE HRRR IS HINTING THAT SOMETHING MAY
DEVELOP, BUT IT IS AT THE END OF ITS MODEL RUN AND WOULD LIKE TO
SEE WHAT IT DOES WITH THIS BEFORE PUTTING ANYTHING IN THE FORECAST
FOR THIS AFTERNOON. HAVE KEPT POPS JUST BELOW SLIGHT CHC FOR THE
INTERIOR FOR NOW.
BY WEDNESDAY, A DEVELOPING LOW OVER THE WESTERN GULF OF MEXICO
WILL CAUSE THE DEVELOPMENT OF A WARM FRONT ACROSS NORTH FLORIDA.
THIS WILL ALLOW FOR A SOUTHEASTERLY FLOW, WHICH WILL HAVE SOME
LIFT. THIS COULD ALLOW SOME SHOWERS TO DEVELOP ALONG THE BORDER
WITH CENTRAL FLORIDA. HAVE KEPT SLIGHT CHANCE POPS IN FOR THAT
AREA INTO THE EVENING HOURS. SPC DOES OUTLOOK THE AREA FOR A
GENERAL THUNDERSTORM, BUT THERE IS BETTER 500MB VORTICITY
ADVECTION TO THE NORTH, OVER CENTRAL FLORIDA. SO, KEPT THUNDERSTORMS
OUT OF THE FORECAST FOR WEDNESDAY AFTERNOON WITH THIS FORECAST
ISSUANCE.
THE LOW, THAT CAUSED THE WARM FRONT, WILL QUICKLY STRENGTHEN AND
MOVE NORTHEAST OVER THE FLORIDA PANHANDLE BY FRIDAY MORNING. THE
ASSOCIATED COLD FRONT WILL MAKE ITS WAY ACROSS THE GULF AND WILL
FIRST IMPACT CENTRAL FLORIDA. MODELS ARE STILL IN PRETTY GOOD
AGREEMENT WITH THE STRENGTH, PLACEMENT, AND TIMING OF THE LOW, WITH
A FEW MINOR DISCREPANCIES. THEY SHOW THE SOUTH FLORIDA COULD SEE
SOME SHOWER ACTIVITY MOVING INTO THE AREA BY 12Z FRIDAY. THERE ARE
INDICATIONS THAT A PRE-FRONTAL TROUGH WILL MOVE ACROSS THE AREA BY
18Z AND THEN THE MAIN FRONT WILL PUSH THROUGH SOMETIME AROUND 00Z
SATURDAY. THERE IS A STRONG 500MB TROUGH/LOW, DEPENDING ON WHICH
MODEL YOU LOOK AT, ASSOCIATED WITH THIS SYSTEM. THIS WILL HELP TO
DEVELOP SOME HEAVIER SHOWERS. THE MAIN QUESTION IS THE THREAT OF
THUNDERSTORMS. CURRENTLY, IT IS DIFFICULT TO TELL HOW HIGH THE
PROBABILITY OF THUNDERSTORMS WILL BE. THE REASON IS THAT THE
ATMOSPHERE COULD GET MIXED WELL BY THE PRE-FRONTAL TROUGH AND KEEP
THE SKIES CLOUDY, REDUCING DAYTIME HEATING. THIS COULD REDUCE THE
POTENTIAL, BUT DONT THINK ELIMINATE IT. HAVE KEPT HIGH CHC POPS IN
FOR FRIDAY AND EVEN MENTION A SLIGHT CHANCE FOR TSTMS LATE
THURSDAY NIGHT. IF THE ATMOSPHERE IS NOT TOO MIXED EARLY ON, THERE
COULD BE A DECENT COVERAGE OF STORMS, AND SOME OF THOSE COULD
BECOME STRONG. BUT, IT IS STILL TOO FAR OUT TOO MAKE ANY REAL
ASSUMPTIONS. SO WILL KEEP IT SIMPLE WITH A CHC OF SHOWERS AND
TSTMS FOR NOW.
BEHIND THIS FRONT, TEMPERATURES ARE NOT GOING TO BE TOO GREATLY
AFFECTED AND HIGH PRESSURE WILL BUILD IN TO BRING QUIET WEATHER
FOR THE WEEKEND AND THE BEGINNING OF NEXT WEEK. CURRENTLY LOOKING
AT MID TO UPPER 70S FOR THE COASTAL AREAS TO LOW 80S IN THE
INTERIOR PORTIONS ON SATURDAY, WITH HIGH A FEW DEGREES HIGHER ON
SUNDAY.
MARINE...
HIGH PRESSURE WILL BUILD IN TODAY. THIS WILL KEEP THE WEATHER
QUIET OVER THE GULF AND ATLANTIC WATERS FOR TODAY THROUGH TOMORROW
MORNING. AN APPROACHING SYSTEM WILL BRING A CHANCE FOR SOME
SHOWERS TO THE AREA AS EARLY AS WEDNESDAY LATE AFTERNOON.
FIRE WEATHER...
FOG IS THE MAIN FIRE WEATHER CONCERN THIS MORNING. SOME OF THE
AREAS ARE DENSE, AND MAYBE MORE SO DUE TO THE SMOKE FROM THE
HUCKABEE FIRE IN COLLIER COUNTY. CONDITIONS SHOULD IMPROVE WITHIN A
COUPLE OF HOURS AFTER SUNRISE. HIGH PRESSURE WILL BUILD IN TODAY
AND HIGH TEMPERATURES WILL FLIRT WITH 90 DEGREES IN THE INTERIOR.
THIS WILL LIKELY ALLOW A SEA BREEZE TO DEVELOP THIS AFTERNOON.
CURRENT MODELS DO SHOW THE SEA BREEZES CONVERGING OVER THE CENTRAL
PART OF THE STATE, QUITE POSSIBLY NEAR THE HUCKABEE FIRE. THIS
COULD LEAD TO BETTER INSTABILITY IN THE VICINITY OF THE FIRE.
THERE IS ALSO A SMALL POSSIBILITY OF SOME SHOWERS DEVELOPING IN
THE AREA THEY CONVERGE, BUT TOO EARLY TO TELL.
A LOW WILL BEGIN TO DEVELOP IN THE WESTERN GULF TODAY AND A WARM
FRONT WILL SET UP OVER NORTH FLORIDA. THIS COULD ALLOW SOME
SHOWERS TO BEGIN TO DEVELOP AS FAR SOUTH AS HENDRY/INTERIOR
COLLIER COUNTIES TOMORROW AFTERNOON. A COLD FRONT IS EXPECTED TO
MOVE ACROSS THE AREA FRIDAY, BRINGING SHOWERS AND POSSIBLY
THUNDERSTORMS TO THE AREA BEGINNING EARLY FRIDAY MORNING, THROUGH
FRIDAY EVENING.
PREV DISCUSSION... /ISSUED 138 AM EDT TUE APR 2 2013/
AVIATION...
FOG WAS BEGINNING TO DEVELOP ACROSS THE INTERIOR AND TOWARDS KAPF
EARLY THIS MORNING. MVFR CONDITIONS ARE EXPECTED TO DEVELOP OVER
THE NEXT FEW HOURS THROUGH 14Z. IFR CONDITIONS COULD BRIEFLY OCCUR
AT KAPF. SEA FOG IS POSSIBLE TO THE WEST OF KAPF OVER THE GULF
TODAY AS WELL. LIGHT WINDS WILL CONTINUE OVERNIGHT. SEA BREEZE
BOUNDARIES ARE EXPECTED TO DEVELOP BY EARLY AFTERNOON AT BOTH
COASTS. WINDS WILL SLOWLY DIMINISH AFTER SUNSET TO AROUND 5 KT.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 81 68 80 69 / - - 10 20
FORT LAUDERDALE 82 71 81 71 / 10 - 10 0
MIAMI 83 70 81 70 / 20 - 10 0
NAPLES 80 64 81 66 / - - 10 -
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...85/AG
AVIATION/RADAR...60/BD
AREA FORECAST DISCUSSION
NWS MIAMI FL
745 AM EDT TUE APR 2 2013
.UPDATE...
FOR THE SHORT TERM...DENSE FOG CONTINUES TO AFFECT MOST OF THE
SOUTH FLORIDA PENINSULA. THE ONLY TERMINALS NOT CURRENTLY AFFECTED
WITH IFR VISIBILITY RESTRICTIONS ARE KMIA AND KOPF...BUT THESE
TERMINALS COULD EXPERIENCE BRIEF PERIODS OF MIST AND/OR FOG OVER
THE NEXT HOUR OR SO WITH SUB-VFR VIS RESTRICTIONS AND WILL AMEND AS
NECESSARY. OTHERWISE...BY MID MORNING AND THROUGH THE AFTERNOON
MAINLY VFR CONDITIONS EXPECTED ALL TERMINALS. WITH LIGHT VARIABLE
FLOW THIS MORNING...THE WEST AND EAST COAST SEA BREEZES ARE
EXPECTED TO FORM TODAY.
60
&&
.PREV DISCUSSION... /ISSUED 647 AM EDT TUE APR 2 2013/
UPDATE...
SHORT TERM MODELS CONTINUE TO INDICATE THE POSSIBILITY OF AN
AFTERNOON SHOWER IN THE INTERIOR PORTION OF THE STATE LATER THIS
AFTERNOON. THE MAIN FOCUS WILL BE THE CONVERGENCE OF THE SEA
BREEZE. CONFIDENCE IS STILL LOW, BUT FEEL THERE IS ENOUGH OF A
CHANCE TO PUT A MENTION IN THE FORECAST FOR TODAY.
PREV DISCUSSION... /ISSUED 447 AM EDT TUE APR 2 2013/
DISCUSSION...
THE WEATHER FOR THE MOST PART IS QUIET. THERE IS SOME DENSE FOG IN
THE WESTERN HALF OF THE FORECAST AREA, AND SOME LOCALIZED FOG NEAR
TAMIAMI. SO, A DENSE FOG ADVISORY IS IN PLACE FOR PORTIONS OF
SOUTH FLORIDA. THIS FOG SHOULD BURN OFF WITHIN A COUPLE OF HOURS
AFTER SUNRISE.
OTHERWISE, HIGH PRESSURE IS BUILDING IN TODAY. AREAS IN THE
INTERIOR PORTIONS OF THE STATE WILL SEE HIGH TEMPERATURES IN THE
MID TO UPPER 90S. COASTAL AREAS WILL SEE HIGHS IN THE LOW TO MID
80S. THERE SHOULD BE A DECENT SEA BREEZE TO DEVELOP TODAY. WITH
SOME MOISTURE, WILL HAVE TO WATCH FOR INDICATIONS THAT SOME
SHOWERS MAY DEVELOP IN THE INTERIOR, ESPECIALLY IF THERE IS ANY
SEA BREEZE CONVERGENCE. NAM MODEL SOUNDINGS ARE SHOWING A GOOD CAP
BETWEEN 500 AND 600 MB. THE HRRR IS HINTING THAT SOMETHING MAY
DEVELOP, BUT IT IS AT THE END OF ITS MODEL RUN AND WOULD LIKE TO
SEE WHAT IT DOES WITH THIS BEFORE PUTTING ANYTHING IN THE FORECAST
FOR THIS AFTERNOON. HAVE KEPT POPS JUST BELOW SLIGHT CHC FOR THE
INTERIOR FOR NOW.
BY WEDNESDAY, A DEVELOPING LOW OVER THE WESTERN GULF OF MEXICO
WILL CAUSE THE DEVELOPMENT OF A WARM FRONT ACROSS NORTH FLORIDA.
THIS WILL ALLOW FOR A SOUTHEASTERLY FLOW, WHICH WILL HAVE SOME
LIFT. THIS COULD ALLOW SOME SHOWERS TO DEVELOP ALONG THE BORDER
WITH CENTRAL FLORIDA. HAVE KEPT SLIGHT CHANCE POPS IN FOR THAT
AREA INTO THE EVENING HOURS. SPC DOES OUTLOOK THE AREA FOR A
GENERAL THUNDERSTORM, BUT THERE IS BETTER 500MB VORTICITY
ADVECTION TO THE NORTH, OVER CENTRAL FLORIDA. SO, KEPT THUNDERSTORMS
OUT OF THE FORECAST FOR WEDNESDAY AFTERNOON WITH THIS FORECAST
ISSUANCE.
THE LOW, THAT CAUSED THE WARM FRONT, WILL QUICKLY STRENGTHEN AND
MOVE NORTHEAST OVER THE FLORIDA PANHANDLE BY FRIDAY MORNING. THE
ASSOCIATED COLD FRONT WILL MAKE ITS WAY ACROSS THE GULF AND WILL
FIRST IMPACT CENTRAL FLORIDA. MODELS ARE STILL IN PRETTY GOOD
AGREEMENT WITH THE STRENGTH, PLACEMENT, AND TIMING OF THE LOW, WITH
A FEW MINOR DISCREPANCIES. THEY SHOW THE SOUTH FLORIDA COULD SEE
SOME SHOWER ACTIVITY MOVING INTO THE AREA BY 12Z FRIDAY. THERE ARE
INDICATIONS THAT A PRE-FRONTAL TROUGH WILL MOVE ACROSS THE AREA BY
18Z AND THEN THE MAIN FRONT WILL PUSH THROUGH SOMETIME AROUND 00Z
SATURDAY. THERE IS A STRONG 500MB TROUGH/LOW, DEPENDING ON WHICH
MODEL YOU LOOK AT, ASSOCIATED WITH THIS SYSTEM. THIS WILL HELP TO
DEVELOP SOME HEAVIER SHOWERS. THE MAIN QUESTION IS THE THREAT OF
THUNDERSTORMS. CURRENTLY, IT IS DIFFICULT TO TELL HOW HIGH THE
PROBABILITY OF THUNDERSTORMS WILL BE. THE REASON IS THAT THE
ATMOSPHERE COULD GET MIXED WELL BY THE PRE-FRONTAL TROUGH AND KEEP
THE SKIES CLOUDY, REDUCING DAYTIME HEATING. THIS COULD REDUCE THE
POTENTIAL, BUT DONT THINK ELIMINATE IT. HAVE KEPT HIGH CHC POPS IN
FOR FRIDAY AND EVEN MENTION A SLIGHT CHANCE FOR TSTMS LATE
THURSDAY NIGHT. IF THE ATMOSPHERE IS NOT TOO MIXED EARLY ON, THERE
COULD BE A DECENT COVERAGE OF STORMS, AND SOME OF THOSE COULD
BECOME STRONG. BUT, IT IS STILL TOO FAR OUT TOO MAKE ANY REAL
ASSUMPTIONS. SO WILL KEEP IT SIMPLE WITH A CHC OF SHOWERS AND
TSTMS FOR NOW.
BEHIND THIS FRONT, TEMPERATURES ARE NOT GOING TO BE TOO GREATLY
AFFECTED AND HIGH PRESSURE WILL BUILD IN TO BRING QUIET WEATHER
FOR THE WEEKEND AND THE BEGINNING OF NEXT WEEK. CURRENTLY LOOKING
AT MID TO UPPER 70S FOR THE COASTAL AREAS TO LOW 80S IN THE
INTERIOR PORTIONS ON SATURDAY, WITH HIGH A FEW DEGREES HIGHER ON
SUNDAY.
MARINE...
HIGH PRESSURE WILL BUILD IN TODAY. THIS WILL KEEP THE WEATHER
QUIET OVER THE GULF AND ATLANTIC WATERS FOR TODAY THROUGH TOMORROW
MORNING. AN APPROACHING SYSTEM WILL BRING A CHANCE FOR SOME
SHOWERS TO THE AREA AS EARLY AS WEDNESDAY LATE AFTERNOON.
FIRE WEATHER...
FOG IS THE MAIN FIRE WEATHER CONCERN THIS MORNING. SOME OF THE
AREAS ARE DENSE, AND MAYBE MORE SO DUE TO THE SMOKE FROM THE
HUCKABEE FIRE IN COLLIER COUNTY. CONDITIONS SHOULD IMPROVE WITHIN A
COUPLE OF HOURS AFTER SUNRISE. HIGH PRESSURE WILL BUILD IN TODAY
AND HIGH TEMPERATURES WILL FLIRT WITH 90 DEGREES IN THE INTERIOR.
THIS WILL LIKELY ALLOW A SEA BREEZE TO DEVELOP THIS AFTERNOON.
CURRENT MODELS DO SHOW THE SEA BREEZES CONVERGING OVER THE CENTRAL
PART OF THE STATE, QUITE POSSIBLY NEAR THE HUCKABEE FIRE. THIS
COULD LEAD TO BETTER INSTABILITY IN THE VICINITY OF THE FIRE.
THERE IS ALSO A SMALL POSSIBILITY OF SOME SHOWERS DEVELOPING IN
THE AREA THEY CONVERGE, BUT TOO EARLY TO TELL.
A LOW WILL BEGIN TO DEVELOP IN THE WESTERN GULF TODAY AND A WARM
FRONT WILL SET UP OVER NORTH FLORIDA. THIS COULD ALLOW SOME
SHOWERS TO BEGIN TO DEVELOP AS FAR SOUTH AS HENDRY/INTERIOR
COLLIER COUNTIES TOMORROW AFTERNOON. A COLD FRONT IS EXPECTED TO
MOVE ACROSS THE AREA FRIDAY, BRINGING SHOWERS AND POSSIBLY
THUNDERSTORMS TO THE AREA BEGINNING EARLY FRIDAY MORNING, THROUGH
FRIDAY EVENING.
PREV DISCUSSION... /ISSUED 138 AM EDT TUE APR 2 2013/
AVIATION...
FOG WAS BEGINNING TO DEVELOP ACROSS THE INTERIOR AND TOWARDS KAPF
EARLY THIS MORNING. MVFR CONDITIONS ARE EXPECTED TO DEVELOP OVER
THE NEXT FEW HOURS THROUGH 14Z. IFR CONDITIONS COULD BRIEFLY OCCUR
AT KAPF. SEA FOG IS POSSIBLE TO THE WEST OF KAPF OVER THE GULF
TODAY AS WELL. LIGHT WINDS WILL CONTINUE OVERNIGHT. SEA BREEZE
BOUNDARIES ARE EXPECTED TO DEVELOP BY EARLY AFTERNOON AT BOTH
COASTS. WINDS WILL SLOWLY DIMINISH AFTER SUNSET TO AROUND 5 KT.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 81 68 80 69 / - - 10 20
FORT LAUDERDALE 82 71 81 71 / 10 - 10 0
MIAMI 83 70 81 70 / 20 - 10 0
NAPLES 80 64 81 66 / - - 10 -
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...DENSE FOG ADVISORY UNTIL 9 AM EDT THIS MORNING FOR COASTAL
COLLIER-FAR SOUTH MIAMI DADE-GLADES-HENDRY-INLAND BROWARD-
INLAND COLLIER-INLAND MIAMI DADE-INLAND PALM BEACH-MAINLAND
MONROE-METRO PALM BEACH.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...85/AG
AVIATION/RADAR...60/BD
AREA FORECAST DISCUSSION
NWS MIAMI FL
647 AM EDT TUE APR 2 2013
.UPDATE...
SHORT TERM MODELS CONTINUE TO INDICATE THE POSSIBILITY OF AN
AFTERNOON SHOWER IN THE INTERIOR PORTION OF THE STATE LATER THIS
AFTERNOON. THE MAIN FOCUS WILL BE THE CONVERGENCE OF THE SEA
BREEZE. CONFIDENCE IS STILL LOW, BUT FEEL THERE IS ENOUGH OF A
CHANCE TO PUT A MENTION IN THE FORECAST FOR TODAY.
&&
.PREV DISCUSSION... /ISSUED 447 AM EDT TUE APR 2 2013/
DISCUSSION...
THE WEATHER FOR THE MOST PART IS QUIET. THERE IS SOME DENSE FOG IN
THE WESTERN HALF OF THE FORECAST AREA, AND SOME LOCALIZED FOG NEAR
TAMIAMI. SO, A DENSE FOG ADVISORY IS IN PLACE FOR PORTIONS OF
SOUTH FLORIDA. THIS FOG SHOULD BURN OFF WITHIN A COUPLE OF HOURS
AFTER SUNRISE.
OTHERWISE, HIGH PRESSURE IS BUILDING IN TODAY. AREAS IN THE
INTERIOR PORTIONS OF THE STATE WILL SEE HIGH TEMPERATURES IN THE
MID TO UPPER 90S. COASTAL AREAS WILL SEE HIGHS IN THE LOW TO MID
80S. THERE SHOULD BE A DECENT SEA BREEZE TO DEVELOP TODAY. WITH
SOME MOISTURE, WILL HAVE TO WATCH FOR INDICATIONS THAT SOME
SHOWERS MAY DEVELOP IN THE INTERIOR, ESPECIALLY IF THERE IS ANY
SEA BREEZE CONVERGENCE. NAM MODEL SOUNDINGS ARE SHOWING A GOOD CAP
BETWEEN 500 AND 600 MB. THE HRRR IS HINTING THAT SOMETHING MAY
DEVELOP, BUT IT IS AT THE END OF ITS MODEL RUN AND WOULD LIKE TO
SEE WHAT IT DOES WITH THIS BEFORE PUTTING ANYTHING IN THE FORECAST
FOR THIS AFTERNOON. HAVE KEPT POPS JUST BELOW SLIGHT CHC FOR THE
INTERIOR FOR NOW.
BY WEDNESDAY, A DEVELOPING LOW OVER THE WESTERN GULF OF MEXICO
WILL CAUSE THE DEVELOPMENT OF A WARM FRONT ACROSS NORTH FLORIDA.
THIS WILL ALLOW FOR A SOUTHEASTERLY FLOW, WHICH WILL HAVE SOME
LIFT. THIS COULD ALLOW SOME SHOWERS TO DEVELOP ALONG THE BORDER
WITH CENTRAL FLORIDA. HAVE KEPT SLIGHT CHANCE POPS IN FOR THAT
AREA INTO THE EVENING HOURS. SPC DOES OUTLOOK THE AREA FOR A
GENERAL THUNDERSTORM, BUT THERE IS BETTER 500MB VORTICITY
ADVECTION TO THE NORTH, OVER CENTRAL FLORIDA. SO, KEPT THUNDERSTORMS
OUT OF THE FORECAST FOR WEDNESDAY AFTERNOON WITH THIS FORECAST
ISSUANCE.
THE LOW, THAT CAUSED THE WARM FRONT, WILL QUICKLY STRENGTHEN AND
MOVE NORTHEAST OVER THE FLORIDA PANHANDLE BY FRIDAY MORNING. THE
ASSOCIATED COLD FRONT WILL MAKE ITS WAY ACROSS THE GULF AND WILL
FIRST IMPACT CENTRAL FLORIDA. MODELS ARE STILL IN PRETTY GOOD
AGREEMENT WITH THE STRENGTH, PLACEMENT, AND TIMING OF THE LOW, WITH
A FEW MINOR DISCREPANCIES. THEY SHOW THE SOUTH FLORIDA COULD SEE
SOME SHOWER ACTIVITY MOVING INTO THE AREA BY 12Z FRIDAY. THERE ARE
INDICATIONS THAT A PRE-FRONTAL TROUGH WILL MOVE ACROSS THE AREA BY
18Z AND THEN THE MAIN FRONT WILL PUSH THROUGH SOMETIME AROUND 00Z
SATURDAY. THERE IS A STRONG 500MB TROUGH/LOW, DEPENDING ON WHICH
MODEL YOU LOOK AT, ASSOCIATED WITH THIS SYSTEM. THIS WILL HELP TO
DEVELOP SOME HEAVIER SHOWERS. THE MAIN QUESTION IS THE THREAT OF
THUNDERSTORMS. CURRENTLY, IT IS DIFFICULT TO TELL HOW HIGH THE
PROBABILITY OF THUNDERSTORMS WILL BE. THE REASON IS THAT THE
ATMOSPHERE COULD GET MIXED WELL BY THE PRE-FRONTAL TROUGH AND KEEP
THE SKIES CLOUDY, REDUCING DAYTIME HEATING. THIS COULD REDUCE THE
POTENTIAL, BUT DONT THINK ELIMINATE IT. HAVE KEPT HIGH CHC POPS IN
FOR FRIDAY AND EVEN MENTION A SLIGHT CHANCE FOR TSTMS LATE
THURSDAY NIGHT. IF THE ATMOSPHERE IS NOT TOO MIXED EARLY ON, THERE
COULD BE A DECENT COVERAGE OF STORMS, AND SOME OF THOSE COULD
BECOME STRONG. BUT, IT IS STILL TOO FAR OUT TOO MAKE ANY REAL
ASSUMPTIONS. SO WILL KEEP IT SIMPLE WITH A CHC OF SHOWERS AND
TSTMS FOR NOW.
BEHIND THIS FRONT, TEMPERATURES ARE NOT GOING TO BE TOO GREATLY
AFFECTED AND HIGH PRESSURE WILL BUILD IN TO BRING QUIET WEATHER
FOR THE WEEKEND AND THE BEGINNING OF NEXT WEEK. CURRENTLY LOOKING
AT MID TO UPPER 70S FOR THE COASTAL AREAS TO LOW 80S IN THE
INTERIOR PORTIONS ON SATURDAY, WITH HIGH A FEW DEGREES HIGHER ON
SUNDAY.
MARINE...
HIGH PRESSURE WILL BUILD IN TODAY. THIS WILL KEEP THE WEATHER
QUIET OVER THE GULF AND ATLANTIC WATERS FOR TODAY THROUGH TOMORROW
MORNING. AN APPROACHING SYSTEM WILL BRING A CHANCE FOR SOME
SHOWERS TO THE AREA AS EARLY AS WEDNESDAY LATE AFTERNOON.
FIRE WEATHER...
FOG IS THE MAIN FIRE WEATHER CONCERN THIS MORNING. SOME OF THE
AREAS ARE DENSE, AND MAYBE MORE SO DUE TO THE SMOKE FROM THE
HUCKABEE FIRE IN COLLIER COUNTY. CONDITIONS SHOULD IMPROVE WITHIN A
COUPLE OF HOURS AFTER SUNRISE. HIGH PRESSURE WILL BUILD IN TODAY
AND HIGH TEMPERATURES WILL FLIRT WITH 90 DEGREES IN THE INTERIOR.
THIS WILL LIKELY ALLOW A SEA BREEZE TO DEVELOP THIS AFTERNOON.
CURRENT MODELS DO SHOW THE SEA BREEZES CONVERGING OVER THE CENTRAL
PART OF THE STATE, QUITE POSSIBLY NEAR THE HUCKABEE FIRE. THIS
COULD LEAD TO BETTER INSTABILITY IN THE VICINITY OF THE FIRE.
THERE IS ALSO A SMALL POSSIBILITY OF SOME SHOWERS DEVELOPING IN
THE AREA THEY CONVERGE, BUT TOO EARLY TO TELL.
A LOW WILL BEGIN TO DEVELOP IN THE WESTERN GULF TODAY AND A WARM
FRONT WILL SET UP OVER NORTH FLORIDA. THIS COULD ALLOW SOME
SHOWERS TO BEGIN TO DEVELOP AS FAR SOUTH AS HENDRY/INTERIOR
COLLIER COUNTIES TOMORROW AFTERNOON. A COLD FRONT IS EXPECTED TO
MOVE ACROSS THE AREA FRIDAY, BRINGING SHOWERS AND POSSIBLY
THUNDERSTORMS TO THE AREA BEGINNING EARLY FRIDAY MORNING, THROUGH
FRIDAY EVENING.
PREV DISCUSSION... /ISSUED 138 AM EDT TUE APR 2 2013/
AVIATION...
FOG WAS BEGINNING TO DEVELOP ACROSS THE INTERIOR AND TOWARDS KAPF
EARLY THIS MORNING. MVFR CONDITIONS ARE EXPECTED TO DEVELOP OVER
THE NEXT FEW HOURS THROUGH 14Z. IFR CONDITIONS COULD BRIEFLY OCCUR
AT KAPF. SEA FOG IS POSSIBLE TO THE WEST OF KAPF OVER THE GULF
TODAY AS WELL. LIGHT WINDS WILL CONTINUE OVERNIGHT. SEA BREEZE
BOUNDARIES ARE EXPECTED TO DEVELOP BY EARLY AFTERNOON AT BOTH
COASTS. WINDS WILL SLOWLY DIMINISH AFTER SUNSET TO AROUND 5 KT.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 81 68 80 69 / - - 10 20
FORT LAUDERDALE 82 71 81 71 / 10 - 10 0
MIAMI 83 70 81 70 / 20 - 10 0
NAPLES 80 64 81 66 / - - 10 -
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...DENSE FOG ADVISORY UNTIL 9 AM EDT THIS MORNING FOR COASTAL
COLLIER-FAR SOUTH MIAMI DADE-GLADES-HENDRY-INLAND BROWARD-
INLAND COLLIER-INLAND MIAMI DADE-INLAND PALM BEACH-MAINLAND
MONROE-METRO PALM BEACH.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...13/SI
AVIATION/RADAR...84/AK
AREA FORECAST DISCUSSION
NWS MIAMI FL
447 AM EDT TUE APR 2 2013
.DISCUSSION...
THE WEATHER FOR THE MOST PART IS QUIET. THERE IS SOME DENSE FOG IN
THE WESTERN HALF OF THE FORECAST AREA, AND SOME LOCALIZED FOG NEAR
TAMIAMI. SO, A DENSE FOG ADVISORY IS IN PLACE FOR PORTIONS OF
SOUTH FLORIDA. THIS FOG SHOULD BURN OFF WITHIN A COUPLE OF HOURS
AFTER SUNRISE.
OTHERWISE, HIGH PRESSURE IS BUILDING IN TODAY. AREAS IN THE
INTERIOR PORTIONS OF THE STATE WILL SEE HIGH TEMPERATURES IN THE
MID TO UPPER 90S. COASTAL AREAS WILL SEE HIGHS IN THE LOW TO MID
80S. THERE SHOULD BE A DECENT SEA BREEZE TO DEVELOP TODAY. WITH
SOME MOISTURE, WILL HAVE TO WATCH FOR INDICATIONS THAT SOME
SHOWERS MAY DEVELOP IN THE INTERIOR, ESPECIALLY IF THERE IS ANY
SEA BREEZE CONVERGENCE. NAM MODEL SOUNDINGS ARE SHOWING A GOOD CAP
BETWEEN 500 AND 600 MB. THE HRRR IS HINTING THAT SOMETHING MAY
DEVELOP, BUT IT IS AT THE END OF ITS MODEL RUN AND WOULD LIKE TO
SEE WHAT IT DOES WITH THIS BEFORE PUTTING ANYTHING IN THE FORECAST
FOR THIS AFTERNOON. HAVE KEPT POPS JUST BELOW SLIGHT CHC FOR THE
INTERIOR FOR NOW.
BY WEDNESDAY, A DEVELOPING LOW OVER THE WESTERN GULF OF MEXICO
WILL CAUSE THE DEVELOPMENT OF A WARM FRONT ACROSS NORTH FLORIDA.
THIS WILL ALLOW FOR A SOUTHEASTERLY FLOW, WHICH WILL HAVE SOME
LIFT. THIS COULD ALLOW SOME SHOWERS TO DEVELOP ALONG THE BORDER
WITH CENTRAL FLORIDA. HAVE KEPT SLIGHT CHANCE POPS IN FOR THAT
AREA INTO THE EVENING HOURS. SPC DOES OUTLOOK THE AREA FOR A
GENERAL THUNDERSTORM, BUT THERE IS BETTER 500MB VORTICITY
ADVECTION TO THE NORTH, OVER CENTRAL FLORIDA. SO, KEPT THUNDERSTORMS
OUT OF THE FORECAST FOR WEDNESDAY AFTERNOON WITH THIS FORECAST
ISSUANCE.
THE LOW, THAT CAUSED THE WARM FRONT, WILL QUICKLY STRENGTHEN AND
MOVE NORTHEAST OVER THE FLORIDA PANHANDLE BY FRIDAY MORNING. THE
ASSOCIATED COLD FRONT WILL MAKE ITS WAY ACROSS THE GULF AND WILL
FIRST IMPACT CENTRAL FLORIDA. MODELS ARE STILL IN PRETTY GOOD
AGREEMENT WITH THE STRENGTH, PLACEMENT, AND TIMING OF THE LOW, WITH
A FEW MINOR DISCREPANCIES. THEY SHOW THE SOUTH FLORIDA COULD SEE
SOME SHOWER ACTIVITY MOVING INTO THE AREA BY 12Z FRIDAY. THERE ARE
INDICATIONS THAT A PRE-FRONTAL TROUGH WILL MOVE ACROSS THE AREA BY
18Z AND THEN THE MAIN FRONT WILL PUSH THROUGH SOMETIME AROUND 00Z
SATURDAY. THERE IS A STRONG 500MB TROUGH/LOW, DEPENDING ON WHICH
MODEL YOU LOOK AT, ASSOCIATED WITH THIS SYSTEM. THIS WILL HELP TO
DEVELOP SOME HEAVIER SHOWERS. THE MAIN QUESTION IS THE THREAT OF
THUNDERSTORMS. CURRENTLY, IT IS DIFFICULT TO TELL HOW HIGH THE
PROBABILITY OF THUNDERSTORMS WILL BE. THE REASON IS THAT THE
ATMOSPHERE COULD GET MIXED WELL BY THE PRE-FRONTAL TROUGH AND KEEP
THE SKIES CLOUDY, REDUCING DAYTIME HEATING. THIS COULD REDUCE THE
POTENTIAL, BUT DONT THINK ELIMINATE IT. HAVE KEPT HIGH CHC POPS IN
FOR FRIDAY AND EVEN MENTION A SLIGHT CHANCE FOR TSTMS LATE
THURSDAY NIGHT. IF THE ATMOSPHERE IS NOT TOO MIXED EARLY ON, THERE
COULD BE A DECENT COVERAGE OF STORMS, AND SOME OF THOSE COULD
BECOME STRONG. BUT, IT IS STILL TOO FAR OUT TOO MAKE ANY REAL
ASSUMPTIONS. SO WILL KEEP IT SIMPLE WITH A CHC OF SHOWERS AND
TSTMS FOR NOW.
BEHIND THIS FRONT, TEMPERATURES ARE NOT GOING TO BE TOO GREATLY
AFFECTED AND HIGH PRESSURE WILL BUILD IN TO BRING QUIET WEATHER
FOR THE WEEKEND AND THE BEGINNING OF NEXT WEEK. CURRENTLY LOOKING
AT MID TO UPPER 70S FOR THE COASTAL AREAS TO LOW 80S IN THE
INTERIOR PORTIONS ON SATURDAY, WITH HIGH A FEW DEGREES HIGHER ON
SUNDAY.
&&
.MARINE...
HIGH PRESSURE WILL BUILD IN TODAY. THIS WILL KEEP THE WEATHER
QUIET OVER THE GULF AND ATLANTIC WATERS FOR TODAY THROUGH TOMORROW
MORNING. AN APPROACHING SYSTEM WILL BRING A CHANCE FOR SOME
SHOWERS TO THE AREA AS EARLY AS WEDNESDAY LATE AFTERNOON.
&&
.FIRE WEATHER...
FOG IS THE MAIN FIRE WEATHER CONCERN THIS MORNING. SOME OF THE
AREAS ARE DENSE, AND MAYBE MORE SO DUE TO THE SMOKE FROM THE
HUCKABEE FIRE IN COLLIER COUNTY. CONDITIONS SHOULD IMPROVE WITHIN A
COUPLE OF HOURS AFTER SUNRISE. HIGH PRESSURE WILL BUILD IN TODAY
AND HIGH TEMPERATURES WILL FLIRT WITH 90 DEGREES IN THE INTERIOR.
THIS WILL LIKELY ALLOW A SEA BREEZE TO DEVELOP THIS AFTERNOON.
CURRENT MODELS DO SHOW THE SEA BREEZES CONVERGING OVER THE CENTRAL
PART OF THE STATE, QUITE POSSIBLY NEAR THE HUCKABEE FIRE. THIS
COULD LEAD TO BETTER INSTABILITY IN THE VICINITY OF THE FIRE.
THERE IS ALSO A SMALL POSSIBILITY OF SOME SHOWERS DEVELOPING IN
THE AREA THEY CONVERGE, BUT TOO EARLY TO TELL.
A LOW WILL BEGIN TO DEVELOP IN THE WESTERN GULF TODAY AND A WARM
FRONT WILL SET UP OVER NORTH FLORIDA. THIS COULD ALLOW SOME
SHOWERS TO BEGIN TO DEVELOP AS FAR SOUTH AS HENDRY/INTERIOR
COLLIER COUNTIES TOMORROW AFTERNOON. A COLD FRONT IS EXPECTED TO
MOVE ACROSS THE AREA FRIDAY, BRINGING SHOWERS AND POSSIBLY
THUNDERSTORMS TO THE AREA BEGINNING EARLY FRIDAY MORNING, THROUGH
FRIDAY EVENING.
&&
.PREV DISCUSSION... /ISSUED 138 AM EDT TUE APR 2 2013/
AVIATION...
FOG WAS BEGINNING TO DEVELOP ACROSS THE INTERIOR AND TOWARDS KAPF
EARLY THIS MORNING. MVFR CONDITIONS ARE EXPECTED TO DEVELOP OVER
THE NEXT FEW HOURS THROUGH 14Z. IFR CONDITIONS COULD BRIEFLY OCCUR
AT KAPF. SEA FOG IS POSSIBLE TO THE WEST OF KAPF OVER THE GULF
TODAY AS WELL. LIGHT WINDS WILL CONTINUE OVERNIGHT. SEA BREEZE
BOUNDARIES ARE EXPECTED TO DEVELOP BY EARLY AFTERNOON AT BOTH
COASTS. WINDS WILL SLOWLY DIMINISH AFTER SUNSET TO AROUND 5 KT.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 81 68 80 69 / - - 10 20
FORT LAUDERDALE 82 71 81 71 / - - 10 0
MIAMI 83 70 81 70 / - - 10 0
NAPLES 80 64 81 66 / - - 10 -
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...DENSE FOG ADVISORY UNTIL 9 AM EDT THIS MORNING FOR GLADES-HENDRY-
INLAND BROWARD-INLAND COLLIER-INLAND MIAMI DADE-INLAND PALM
BEACH.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...13/SI
AVIATION/RADAR...84/AK
AREA FORECAST DISCUSSION...UPDATE
NWS PEACHTREE CITY GA
140 AM EDT TUE APR 2 2013
.UPDATE...
TWO WEAK BOUNDARIES ACROSS THE CWFA THIS EVENING...BOTH WEAK COLD
FRONTS. THE FIRST FRONT IS ACROSS NORTHERN GA AND THE SECOND IS
ACROSS THE SOUTHERN CWFA. NO REAL MOISTURE ASSOCIATED WITH EITHER
OF THESE FEATURES OTHER THAN SOME CU...SO HAVE REMOVED THE MENTION
OF POPS. ANY SCT CU SHOULD ALSO DISSIPATE WITH SUNSET.
TWEAKED HOURLY TEMPS A BIT...THEY WERE NOT FALLING OFF AS FAST AS
FORECAST. ADJUSTED THE MIN TEMPS A FEW HOURS...WITH THE METRO AREA
A COUPLE OF DEGREES WARMER.
&&
.PREV DISCUSSION... /ISSUED 350 PM EDT MON APR 1 2013/
..BRIEF DRY PERIOD BEFORE RAIN RETURNS MID WEEK...
SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
LATEST SURFACE ANALYSIS SHOWS SEMI PERMANENT SURFACE TROUGH FROM
JUST SOUTH OF ATHENS THROUGH COLUMBUS. ALONG AND SOUTH OF THIS
FEATURE MOISTURE SURFACE CONVERGENCE HAS RESULTED IN SCATTERED TO
BROKEN CU DEVELOPMENT BUT SHOWER ACTIVITY HAS REMAINED OUTSIDE OF
THE FORECAST AREA. FURTHER NORTH...SURFACE FRONT CONTINUES TO SAG
INTO NORTH GA WITH MOISTURE POOLING ALONG ITS LEADING EDGE AS WELL
AND ADDITIONAL CLOUD DEVELOPMENT THE RESULT.
THIS SHOULD REMAIN JUST CLOUDS WITH NO PRECIP FOR THIS EVENING AS
MAIN FOCUS WILL BE ON SOUTHERN TROUGH AND IT AFFECTS ON CENTRAL
GEORGIA. LOOKING AT THE LATEST RAP ANALYSIS OF CAPE IN THIS
VICINITY AND WE SEE 500 J/KG TO 1000 J/KG OF AVAILABLE
ENERGY...SLIGHTLY HIGHER THAN MODEL PROJECTIONS. STILL LOOKING AT
500MN TEMPS IN THE VERY COLD RANGE OF -17C IN THIS AREA SO ANY
SUSTAINED UPDRAFTS WILL BE CAPABLE OF PRODUCING LARGE HAIL.
ACTIVITY WILL SHIFT EAST QUICKLY THIS EVENING WITH CLEARING
CONDITIONS TAKING PLACE. STILL SOME GRADIENT IN PLACE ACROSS THE
AREA WHICH WILL PREVENT OPTIMUM RADIATIONAL COOLING CONDITIONS.
WENT WITH A MAV/MET BLEND FOR THE OVERNIGHT TEMPS WHICH WILL BE
TRICKY TO THE SOUTH BASED ON HOW FAST CLOUDS CLEAR.
SURFACE FRONT LOOKS TO STALL ACROSS NORTH GEORGIA TUESDAY AND
IMPULSES OF ENERGY BEGIN TO ROUND PERIPHERY OF EAST COAST TROUGH.
THIS SHOULD ALLOW A FEW LIGHT SHOWERS TO DEVELOP ACROSS EXTREME
NORTH GEORGIA AND HAVE INCLUDED IN THIS GRID PACKAGE. AS HIGH
BRIDGES ACROSS THROUGH TUESDAY NIGHT...MAY SEE FRONT SAG FURTHER
SOUTH AND TAKE 20 POPS ALONG WITH IT INTO THE REMAINDER OF NORTH
GEORGIA.
DEESE
LONG TERM /WEDNESDAY THROUGH MONDAY/...
MAIN CONCERN FOR THE EXTENDED REMAINS THE SYSTEM MOVING THROUGH
THE STATE ON WEDNESDAY INTO THE END OF THE WORK WEEK.
DISCREPANCIES STILL REMAIN BETWEEN THE EURO AND GFS AS FAR AS
TIMING OF THE SYSTEM LEAVING THE CWA. THE 12Z MODELS ARE
STRIKINGLY SIMILAR TO THEIR 00Z COUNTERPARTS. AS SUCH...WAS NOT
ABLE TO NAIL DOWN AN ACCURATE END TO THE RAIN THIS WEEK. ACCORDING
TO HPC MODEL DISCUSSIONS THE EURO IS AN OUTLIER...MOVING THE
SYSTEM FURTHER SOUTH AND IS SLOWER. THAT SAID THEY DECIDED TO WITH
A BLEND BETWEEN THE 00Z EURO AND THE 06Z GEFS. WITH THIS MUCH
UNCERTAINTY DECIDED TO ONLY CHANGE THE COVERAGE OF THUNDER ON
WEDNESDAY AND LEAVE THE REST OF THE FORECAST ALONE. DID LOWER
TEMPS ON THURSDAY AS A PSEUDO WEDGE BUILDS IN. CLOUDS AND RAIN IN
ASSOCIATION WITH THIS WEDGE SHOULD HELP TO KEEP TEMPS LOW. HAVE
INCLUDED PREVIOUS EXTENDED BELOW/
ARG
LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... POTENTIAL FOR A HEAVY
RAIN/SEVERE WEATHER EVENT SETTING UP IN THE THURSDAY TO THURSDAY
NIGHT TIME FRAME. MODELS SIMILAR WITH SPREADING DEEPER MOISTURE
INTO THE AREA LATE WEDNESDAY BUT THE MAIN PRECIP PERIOD LOOKS TO
BE WEDNESDAY NIGHT THRU THURSDAY NIGHT. AN OVERRUNNING PATTERN
WILL SET LATE WEDNESDAY/WEDNESDAY NIGHT WITH MODELS DEVELOPING A
WARM FRONT ALONG THE GULF COAST. SURFACE LOW PRESSURE DEVELOPS
OVER THE WESTERN GULF AND MOVES TO THE WESTERN FL PANHANDLE LATE
THURSDAY AND THEN ACROSS CENTRAL TO S GA THURSDAY NIGHT/FRIDAY.
THE GFS IS FASTER WITH THIS PROGRESSION THAN THE EUROPEAN. THIS
TRACK COULD MOVE THE WARM FRONT INTO THE SE CWA AND GIVE POTENTIAL
FOR SEVERE THUNDERSTORMS MAINLY THURSDAY NIGHT. IT WILL ALSO GIVE
POTENTIAL FOR HEAVY RAIN ACROSS A LARGE PORTION OF EAST GEORGIA
AND MODELS IN GENERAL ARE LESS GUN-OH WITH PRECIP AMOUNTS WITH A
LARGE AREA OF 1-2 INCHES FORECAST. THE UPPER TROUGH MOVES ACROSS
THE AREA ON FRIDAY AND THE GFS IS FASTER WITH THIS PROGRESSION
THAN THE EUROPEAN. THE AIRMASS DRIES OUT FOR SATURDAY AND MOSTLY
LIKELY SUNDAY WITH THE EUROPEAN INDICATING SOME MOISTURE
ASSOCIATED WITH A SHORT WAVE ON SUNDAY...MOST SO FOR N GA. FOR NOW
WILL KEEP THINGS DRY AND MONITOR THE PROGRESSION. A SHORT WAVE
RIDGE BUILDS FOR MONDAY WITH THE EUROPEAN CONTINUING TO SHOW MORE
MOISTURE SKIRTING OVER N GA THAN THE GFS.
BDL
AVIATION...
06Z UPDATE...
VFR THROUGH THE FORECAST PERIOD. SOME SCT050-060 POSSIBLE DURING THE
AFTERNOON. LIGHT NORTHWEST WINDS WILL CONTINUE UNTIL AROUND 12Z THEN
A BRIEF PERIOD OF NORTH FLOW IS POSSIBLE DURING THE MORNING BUT
PREDOMINATELY NORTHWEST DURING THE AFTERNOON.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM ON WIND SHIFT.
HIGH ON REMAINING ELEMENTS.
41
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 42 69 41 64 / 10 10 20 20
ATLANTA 47 67 44 64 / 5 5 20 20
BLAIRSVILLE 37 58 35 63 / 10 10 20 20
CARTERSVILLE 41 65 40 64 / 5 10 20 20
COLUMBUS 51 75 50 70 / 5 5 5 30
GAINESVILLE 44 65 43 61 / 10 10 20 20
MACON 45 75 44 69 / 5 5 5 30
ROME 38 65 38 64 / 5 10 20 20
PEACHTREE CITY 40 70 42 65 / 5 5 20 30
VIDALIA 55 76 51 74 / 20 0 5 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CARIBOU ME
627 AM EDT TUE APR 2 2013
.SYNOPSIS...
A COLD AIR MASS WILL REMAIN IN PLACE ACROSS THE REGION THROUGH
WEDNESDAY. DISTURBANCES ROTATING AROUND AN EASTERN CANADIAN LOW
WILL PRODUCE SNOW SHOWERS ACROSS NORTHERN AND WESTERN MAINE TODAY
INTO TONIGHT THAT WILL BECOME SCATTERED WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
0615AM UPDATE...
VERY DRY AIR IS WORKING SOUTHWARD THROUGH THE FORECAST AREA THIS
MORNING. ADJUSTED DEW POINTS DOWN AND WIND GUSTS UP IN LATEST
UPDATE. ALSO ADDED CHANCE POPS FOR SNOW SHOWERS FOR BANGOR BY
MIDDAY AS HRRR AND RUC ARE SHOWING A WEAK SURFACE TROUGH MOVING
ACROSS THE AREA EARLY THIS AFTERNOON. ANOTHER TROUGH APPEARS IN
NORTHERN MAINE LATE THIS AFTERNOON WITH THE CHANCE OF SOME
BRIEF...HEAVIER SNOW SHOWERS IN AROOSTOOK. OTHERWISE...EXPECT A
LOT OF WEAKER SNOW SHOWERS POPPING UP ACROSS THE FORECAST AREA
THIS AFTERNOON.
A COLD UPPER LOW WILL MOVE JUST NORTH OF THE FORECAST AREA THIS
AFTERNOON. COLD AIR ALOFT COMBINED WITH H850 MOISTURE WILL PRODUCE
INSTABILITY TO NEAR H700 THIS AFTERNOON AND EVENING. THE RESULTING
SNOW SHOWERS WILL BE MOST LIKELY IN THE CROWN OF MAINE...BUT A FEW
SHOWERS WILL OCCUR ALL THE WAY SOUTH TO THE COAST THIS AFTERNOON.
THE MIXING ASSOCIATED WITH THIS INSTABILITY WILL PRODUCE A WINDY
DAY WITH WEST WINDS GUSTING TO OVER 30 MPH. THE WELL MIXED
ATMOSPHERE WILL PRODUCE A MIXTURE OF SUN AND CLOUDS BUT WILL GO
WITH MOSTLY CLOUDY IN MOST ZONES THIS AFTERNOON. SOME LOCATIONS
MAY RECEIVE MULTIPLE SNOW SHOWERS DURING THE COURSE OF THE
AFTERNOON. TEMPERATURES WILL ONLY REACH THE UPPER 20S NORTH AND
LOW 30S FOR BANGOR AND DOWN EAST. THE SNOW SHOWERS WILL CONTINUE
INTO THE EVENING AND THEN SUBSIDENCE ALOFT WILL CREATE
STRATOCUMULUS TONIGHT. THESE CLOUDS AND CONTINUED WINDS WILL ONLY
ALLOW TEMPERATURES TO FALL TO THE MID TO UPPER TEENS NORTH AND LOW
20S FOR BANGOR AND DOWN EAST ZONES.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
A DEEP UPPER LOW ACROSS ERN CANADA WILL ROTATE OUT TO THE
NW AND BEGIN TO GRADUALLY LOOSE ITS GRIP ON THE WEATHER ACROSS
NRN NEW ENGLAND. THE AIR MASS WILL CONTINUE TO BE UNSEASONABLY
COLD WITH AN 850 MB TEMP OF AROUND -17C AT 12Z WED WHICH IS ABOUT
2 STD DEV BELOW NORMAL FOR EARLY APR. THERE WILL STILL BE ENOUGH
CYCLONIC FLOW ALOFT WHICH IS CONDUCIVE FOR MOISTURE AND WEAK
DISTURBANCES TO ROTATE THROUGH AND PRODUCE SCATTERED SNOW SHOWERS
ACROSS THE WESTERN MOUNTAINS AND FAR NORTHERN MAINE...ESPECIALLY
SO ACROSS THE FAVORED UPSLOPE AREAS. TEMPS WILL REMAIN ABOUT 10
DEGREES BELOW NORMAL WITH HIGHS ONLY IN THE UPPER 20S TO LOW 30S
NORTH WITH M/U 30S DOWNEAST. A SFC HIGH SLIDES SOUTH OF THE AREA
THU AS A WEAK CLIPPER APPROACHES FROM THE WEST LATE IN THE DAY.
TEMPERATURES THU PM WILL MODERATE BACK CLOSER TO 40 IN THE NORTH
AND MID 40S DOWNEAST. CLOUDS WILL INCREASE ACROSS THE NORTH AHEAD
OF THE CLIPPER SYSTEM.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
A WEAK FRONTAL BOUNDARY ASSOCIATED WITH THE AFORE MENTIONED
CLIPPER WASHES OUT ACROSS THE AREA FRI AS ATTENTION TURNS TO A
SOUTHERN BRANCH LOW THAT MOVES OFF THE MID ATLANTIC COAST FRI
PM. THE ECMWF HAS BEEN CONSISTENT IN HAVING A WEAKER AND LESS
PHASED SYSTEM THAT PASSES FAR ENOUGH SOUTH OF THE AREA TO KEEP THE
PRECIPITATION SHIED WELL OFFSHORE. THE GFS AND CANADIAN HAVE
STRONGER AND MORE PHASED SOLUTIONS THAT WOULD BRING SOME RAIN OR
MIXED PRECIPITATION CHANGING TO SNOW FOR DOWNEAST AREAS FRI NIGHT.
THE 00Z RUNS OF THE GFS AND CANADIAN ARE A BIT FURTHER EAST WITH
THE LOW WHEN COMPARED TO LAST NIGHTS RUNS. THE ONGOING FORECAST
HAS THIS COVERED WELL WITH HIGH CHANCE POPS DOWNEAST FRI NIGHT. A
RIDGE OF HIGH PRESSURE BRIEFLY BUILDS IN FROM THE WEST SAT AND IS
QUICKLY FOLLOWED BY ANOTHER WEAK CLIPPER THAT MOVES IN FROM THE
WEST SAT NIGHT AND SUN. YET ANOTHER SYSTEM APPROACHES FROM THE
WEST/SOUTHWEST LATE MON WITH THE POTENTIAL FOR ANOTHER MIXED
PRECIPITATION EVENT.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
NEAR TERM: MVFR CIGS EARLY THIS MORNING NORTH OF HOULTON. THESE
CIGS WILL RISE TOWARDS 5000FT THIS AFTERNOON WITH WIDESPREAD SNOW
SHOWERS UP TO 10000FT. STRONG WIND GUSTS AS HIGH AS 35 MPH ARE
EXPECTED THIS AFTERNOON WITH A LOT OF LOW LEVEL TURBULENCE. VIS IN
SNOW SHOWERS COULD DROP BRIEFLY TO IFR THIS AFTERNOON.
SHORT TERM: MVFR AT TIMES AT THE NORTHERN TERMINALS INTO WED
EVENING IN SCT -SHSN. OTHERWISE VFR THROUGH THU NIGHT. MVFR
POSSIBLE FRI IN SCT -SHSN/SHRA. A COASTAL STORM MAY LOWER
CONDITIONS TO IFR FRI NIGHT IN RN/SN AT KBHB AND KBGR.
&&
.MARINE...
NEAR TERM: SCA WILL CONTINUE WITH STRONG WEST WINDS GUSTING TO 35
KT AND SEAS IN THE SIX TO EIGHT FOOT RANGE.
SHORT TERM: THE SCA WAS EXTENDED THROUGH 6 PM WED...AND SUBSEQUENT
SHIFTS WILL LIKELY NEED TO EXTEND IT ONE MORE FORECAST PERIOD
THROUGH WED NIGHT. THE WIND MAY DROP OFF FOR A TIME THU...BUT IS
EXPECTED TO PICK UP AGAIN LATE IN THE DAY AHEAD OF AN APPROACHING
FRONTAL BOUNDARY.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT WEDNESDAY FOR ANZ050>052.
&&
$$
NEAR TERM...MCW
SHORT TERM...CB
LONG TERM...CB
AVIATION...MCW
MARINE...MCW/CB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
138 PM EDT TUE APR 2 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 520 AM EDT TUE APR 2 2013
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEP UPR TROF OVER
THE E HALF OF NAMERICA DOWNSTREAM OF RDG OVER WRN CANADA. CWA
REMAINS DOMINATED BY COLD CYC NW FLOW IN THE WAKE OF SLOWLY
DEPARTING CLOSED LO OVER WRN QUEBEC. ALTHOUGH H85 TEMPS RANGING FM
-14C OVER THE W TO -16C OVER THE E AND INVRN BASE NEAR H8 ARE
SUFFICIENTLY COLD/HI FOR LES EVEN IN THE ABSENCE OF ANY DYNAMIC
FORCING...UPSTREAM 00Z INL/YPL RAOBS ARE SO DRY...WITH THE H925
DEWPT DEPRESSION 15C AT INL IN INVERTED V T/TD PROFILE...THAT THERE
ONLY A FEW WEAK CLD BANDS OVER THE W HALF OF LK SUP STREAMING INTO
THE WRN ZNS. WITH A LONGER FETCH OVER THE E HALF AND A WEAK SFC TROF
PASSING THRU THIS AREA...MORE CLDS/SOME LES BANDS ARE EVIDENT
STREAMING INTO THE CWA E OF MQT. BUT DRYNESS OF AIRMASS IS EVIDENT
IN LO REFLECTIVITIES. LOOKING FARTHER UPSTREAM...THERE IS A FAIRLY
VIGOROUS SHRTWV NEAR LK WINNIPEG DIGGING SEWD. BUT SINCE THE 00Z THE
PAS MANITOBA RAOB IS ALSO QUITE DRY WITH INVERTED V T/TD PROFILE IN
THE LLVLS...THERE ARE ONLY SOME PATCHY MID/HI CLDS IN THE PVA
ASSOCIATED WITH THIS FEATURE. ANOTHER SHRTWV OVER HUDSON BAY IS
DIVING SWD.
EARLY THIS MRNG/TODAY...WITH NOCTURNAL COOLING EARLY THIS MRNG AND
SOME ENHANCED LLVL CNVGC ALONG WEAK SFC TROF...EXPECT SCT-NMRS -SHSN
TO IMPACT THE ERN ZNS THRU THIS MRNG. OVER THE W...THERE SHOULD BE
LTL IF ANY LES OR EVEN LK CLDS THRU 09Z GIVEN THE UPSTREAM
DRYNESS...BUT MODELS SHOW AREA OF DPVA/H85-5 QVECTOR CNVGC
ASSOCIATED WITH SHRTWV DIGGING THRU MN IMPACTING THE FAR W BY 12Z.
SUSPECT MORE CLDS/A FEW -SHSN MIGHT DVLP IN PRESENCE OF NOCTURNAL
COOLING...BUT LLVL DRYNESS WL LIMIT COVERAGE/INTENSITY OF ANY SHSN
THAT MIGHT POP UP. IF THERE IS ANY SHSN...THESE SHOULD DIMINISH ONCE
THE FORCING PASSES TO THE S BY 15Z AND DAYTIME HEATING BEGINS TO
DISRUPT THE LES PROCESS. LATE IN THE DAY...NEXT SHRTWV OVER HUDSON
BAY IS PROGGED TO DIG INTO THE UPR LKS WITH ACCOMPANYING DPVA AND
H85-5 QVECTOR CNVGC IMPACTING THE CWA. ALTHOUGH DAYTIME HEATING
MIGHT ALSO DISRUPT THE LES OVER THE E HALF IN THE AFTN...THE ARRIVAL
OF THIS FORCING MIGHT CAUSE AN UPTICK OF SHSN AGAIN TOWARD 00Z
ESPECIALLY OVER THE E HALF CLOSER TO DEEPER MSTR/COLDER AIR.
AS FOR TEMPS...PREFER TO TEND TOWARD THE HIER END OF GUIDANCE WITH A
GOOD DEAL OF SUNSHINE...AT LEAST OVER THE W AND SCENTRAL.
TNGT...SHRTWV DROPPING S INTO THE UPR LKS AND ACCOMPANYING DYNAMIC
FORCING IS PROGGED TO CROSS THE ERN COUNTIES. WITH LOWER H85 TEMPS
ARND -17C CLOSER TO THE CYC SIDE OF THE TRACK OF THIS DISTURBANCE AS
WELL AS DEEPER MSTR/SOMEWHAT HIER INVRN SHOWN THERE ON FCST SDNGS...
OPTED TO RAISE POPS INTO THE LIKELY RANGE NEAR LK SUP E OF MQT AS
THESE EVENTS OCCUR DURING THE MORE FAVORABLE NOCTURNAL COOLING.
EXPECT MUCH LESS IF ANY ACTIVITY OVER THE W ON THE ACYC SIDE OF THE
SHRTWV PASSAGE AND WHERE FCST SNDGS SHOW MUCH DRIER AIR AND HIER H85
TEMPS/LOWER INVNR BASE. EXPECT THE LOWEST MIN TEMPS TOWARD THE LOWER
END OF GUIDANCE OVER THE INTERIOR W UNDER THE DRIER AIR AND WHERE
WINDS WL BE LIGHTER.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 520 AM EDT TUE APR 2 2013
LOOKS LIKE A PATTERN CHANGE IS IN THE OFFING OVER THE NEXT FEW WEEKS
THAT WILL TRANSITION THE PERSISTENT BELOW NORMAL TEMP REGIME TOWARD
AN ABOVE NORMAL ONE. THE AO AND NAO WHICH HAVE BEEN IN A PREVAILING
NEGATIVE PHASE SINCE EARLY/MID FEB ARE BOTH FORECAST TO TREND TO THE
POSITIVE PHASE...WITH THE AO BECOMING STRONGLY POSITIVE. THIS
SUPPORTS A TREND TOWARD ABOVE NORMAL TEMPS HEADING INTO MID/LATE
APRIL...BUT THIS DOESN`T PRECLUDE THE POTENTIAL FOR MORE WINTRY PCPN
EVENTS BEFORE THE WARMER PATTERN SETS IN. THE PATTERN ALSO APPEARS
TO BE SHIFTING TOWARD AN ACTIVE ONE OVER THE NEXT 2 WEEKS. INTO THE
UPCOMING WEEKEND...FLOW WILL TREND PROGRESSIVE AND FLATTER WITH A
COUPLE OF SHORTWAVES TO AFFECT THE UPPER LAKES...THE FIRST WED
NIGHT/THU AND A SECOND MORE IMPORTANT WAVE SAT. EARLY NEXT WEEK...AN
AMPLIFIED TROF WILL BE DEVELOPING OVER THE WRN CONUS...SIGNALING THE
POTENTIAL FOR MORE SIGNIFICANT PCPN EVENTS NEXT WEEK FROM THE
CNTRL/SRN PLAINS TO THE GREAT LAKES AS THE GULF OPENS UP. THIS COULD
MEAN ONE OR MORE UNWELCOMED RAIN EVENTS ON A MELTING SNOWPACK WHICH
IS STILL DEEP IN THE LAKE EFFECT AREAS OR MORE SNOW COULD STILL BE
ADDED. IN RECENT DAYS...MEDIUM RANGE GUIDANCE HAS TONED DOWN THE
WARMING NEXT WEEK...SO MORE SNOW IS STILL A REAL POSSIBILITY.
BEGINNING WED...SFC HIGH PRES WILL QUICKLY SHIFT ACROSS THE WRN
GREAT LAKES AHEAD OF THE FIRST SHORTWAVE THAT WILL BE TRACKING
ACROSS SASKATCHEWAN/MANITOBA. IF ANY LIGHT LES IS LINGERING OVER THE
ERN FCST AREA TO START THE DAY...IT WILL END QUICKLY IN THE MORNING.
AFTER A PERIOD OF SUNSHINE...HIGH CLOUDS WILL BE ON THE INCREASE.
SUNSHINE WILL SUPPORT A STRONG DIURNAL TEMP SPREAD. AFTER MORNING
LOWS IN THE SINGLE DIGITS OVER THE INTERIOR W...TEMPS SHOULD REBOUND
INTO THE UPPER 30S/LWR 40S.
SHORTWAVE WILL MOVE ACROSS NRN ONTARIO WED NIGHT/THU MORNING. WITH
STRONG DEEP LAYER FORCING/IMPRESSIVE 500MB HEIGHT FALLS (AROUND
200M/12HR) PASSING WELL TO THE N OF HERE...MAIN PCPN AREA WILL PASS
TO THE N OF UPPER MI. NONETHELESS...50-80M HEIGHT FALLS AT 500MB...
RIBBON OF MODEST DEEP LAYER FORCING PER QVECTORS AND ISENTROPIC
ASCENT SUGGEST SOME PCPN POTENTIAL ACROSS THE FCST AREA. WITH
ISENTROPIC ASCENT WEAKENING AS IT SHIFTS ACROSS THE UPPER LAKES...
AND LOW-LEVEL DRY AIR TO OVERCOME INITIALLY...NOTHING MORE THAN LOW
CHC POPS APPEAR WARRANTED ATTM. ALTHOUGH LOW-LEVEL TEMPS ARE JUST
ABOVE 0C PRIOR TO POTENTIAL PCPN ARRIVING...EVAPORATIVE COOLING
SHOULD BE SUFFICIENT SO THAT SNOW BECOMES THE MAIN PTYPE IN MOST
AREAS. PCPN CHC WILL END W TO E THU MORNING WITH DRY WEATHER
FOLLOWING THRU THU NIGHT/FRI AS SFC HIGH PRES RIDGE BUILDS SE INTO
THE UPPER LAKES. 850MB TEMPS FALLING TO AROUND -12C THU NIGHT/FRI
MORNING WILL BE AT THE THRESHOLD FOR LES. HOWEVER...SINCE LOW-LEVEL
FLOW BECOMES MORE ANTICYCLONIC DURING THE NIGHT AND AIR MASS IS
FAIRLY DRY IN THE LOW-LEVELS...WILL NOT INCLUDE ANY MENTION OF
-SHSN. OVER THE W...FLOW IS MORE DIVERGENT...SO THERE MAY NOT EVEN
BE MUCH IN THE WAY OF CLOUDS. OPTED TO GO BLO GUIDANCE THERE THU
NIGHT AS WINDS WILL PROBABLY FALL OFF TO CALM AS HIGH PRES RIDGE
NEARS. ALTHOUGH LOWERED MINS TO THE LOW/MID TEENS...TEMPS COULD
EASILY FALL INTO THE SINGLE DIGITS.
FRI NIGHT/SAT...ATTENTION TURNS TO THE SECOND MORE IMPORTANT
SHORTWAVE TRACKING ACROSS THE NRN CONUS IN FLATTER FLOW REGIME.
MEDIUM RANGE GUIDANCE IS MOVING TOWARD SLIGHTLY BETTER AGREEMENT
WITH SYSTEM...BUT IMPORTANT DETAILS HAVE YET TO BE NARROWED DOWN.
THE GFS WHICH HAS BEEN CONSISTENTLY FARTHER S HAS TRENDED A LITTLE
FARTHER N WITH WAVE AND IS IN DECENT AGREEMENT WITH THE GLOBAL GEM.
THE ECMWF HAS BEEN CONSISTENTLY FARTHER N. THE GFS TRACK LOOKS TO
SUPPORT ALL SNOW FOR THE FCST AREA AS THE 850MB LOW TRACKS ALONG
WI/UPPER MI BORDER AND 850MB TEMPS REMAIN BLO 0C AND 1000-850MB
THICKNESS IS NO HIGHER THAN 1295M. THE GLOBAL GEM MOSTLY SUPPORTS
ALL SNOW WITH A POSSIBLE CHANGEOVER TO RAIN S AND SE...BUT ITS
SLOWER/MORE WRAPPED UP SYSTEM DOES NOT APPEAR TO FIT THE DEVELOPING
FLATTER FLOW REGIME. HOWEVER...THE 00Z ECMWF ALSO TRENDED MUCH
SLOWER AND SHARPER WITH SHORTWAVE...SO THIS MAY BE AN IMPORTANT
TREND TO MONITOR IN FUTURE MODEL RUNS. THE FARTHER N ECMWF SUGGESTS
MORE OF A MIXED PCPN EVENT WITH MORE SNOW THAN RAIN N AND MORE RAIN
THAN SNOW S. THE HEAVIEST SWATH OF PCPN PASSES ACROSS NRN UPPER MI
IN THE ECMWF...JUST S IN THE GFS AND CLIPS THE SRN FCST AREA IN THE
GLOBAL GEM. WHILE THE DETAILS OF SHORTWAVE TRACK...RESULTING PCPN
AREA AND THE ALL IMPORTANT TEMP PROFILE HAVE YET TO BE AGREED
UPON...WHAT IS A LITTLE MORE CERTAIN IS THAT THIS WAVE MAY BE A
RATHER IMPRESSIVE PCPN PRODUCER DESPITE THE FLATTER FLOW REGIME.
STRONG WAA IS NOTED BY ALL GUIDANCE WITH 850MB WINDS AROUND 50KT.
THE FRONTOGENESIS SIGNAL IS ALSO QUITE STRONG. PROXIMITY OF STEEP
MIDLEVEL LAPSE RATES NEAR THE SRN EDGE OF THE PCPN AREA SUGGESTS
THERE WILL PROBABLY BE SOME CONVECTION AS IS OFTEN SEEN WITH WAVES
RUNNING ALONG THE BAROCLINIC ZONE AT THIS TIME OF YEAR. IT WILL BE A
SYSTEM TO WATCH.
IN THE WAKE OF THE SAT SYSTEM...DRY WEATHER SHOULD FOLLOW FOR SUN
UNDER WEAK SFC HIGH PRES RIDGE...THOUGH IF THE SLOWER GLOBAL GEM AND
ECMWF ARE RIGHT...SOME PCPN COULD LINGER THRU AT LEAST PART OF SUN.
ATTENTION THEN TURNS TO THE SW FOR MON/TUE AS TROF AMPLIFIES INTO
THE WRN CONUS. AMPLIFYING TROF MAY SEND SEVERAL SHORTWAVES INTO THE
GREAT LAKES NEXT WEEK WITH THE FIRST PERHAPS AS SOON AS MON. AS
WOULD BE EXPECTED WITH A DEEPENING WRN TROF...MODELS ARE AND WILL
CONTINUE TO HAVE TROUBLE WITH TIMING AND PLACEMENT OF SHORTWAVES
EJECTING NE...SO THERE IS LITTLE CONFIDENCE RIGHT NOW IN THE PCPN
FCST MON/TUE. WITH GULF OPENING UP AHEAD OF THE LARGE SCALE WRN
TROF...ANY SHORTWAVES AFFECTING THE AREA COULD BE MDT/HVY PCPN
PRODUCERS NEXT WEEK...AND PCPN COULD BE SNOW FOR PORTIONS OF UPPER
MI.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 135 PM EDT TUE APR 2 2013
AN UPPER LEVEL TROUGH WILL PASS THROUGH THE EASTERN PORTION OF THE
UPPER PENINSULA LATE THIS EVENING INTO THE OVERNIGHT HOURS...HOWEVER
THIS SHOULD DO NOTHING MORE THAN BRING INCREASED CLOUD COVER FOR
MAINLY THE CMX AND SAW TAF SITES. CEILINGS AND VISIBILITIES ARE
EXPECTED TO REMAIN VFR THROUGH THE TAF PERIOD. HIGH PRESSURE BUILDING
INTO THE WEST WILL ALLOW THE WINDS TO DECREASE AND BECOME VARIABLE
OVERNIGHT AT THE IWD TAF SITE...BEFORE SHIFTING TO THE SOUTH BY LATE
WEDNESDAY MORNING AS THE HIGH SHIFTS TO THE EAST OF THE AREA. &&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 520 AM EDT TUE APR 2 2013
WHERE THE PRES GRADIENT WILL BE SHARPER CLOSER TO DEPARTING LO PRES
IN SE CANADA...EXPECT NNW WINDS UP TO 30 KTS THRU TONIGHT OVER THE E
ALONG WITH FREEZING SPRAY. LIGHTER WINDS UP TO 20 KTS WILL PREVAIL
OVER THE W WHERE THE GRADIENT WILL BE WEAKER. AFTER A BRIEF PERIOD
OF LIGHT WINDS FOR A PORTION OF WED AS HIGH PRES QUICKLY PASSES...S
TO SW WINDS WILL QUICKLY RAMP UP TO 20-30KT WED AFTN/EVENING AHEAD OF
LOW PRES TRACKING E INTO NRN ONTARIO. ALTHOUGH LOW-LEVEL TEMP PROFILE
IS STABLE...HEALTHLY PRES FALLS PASSING ACROSS NRN ONTARIO SUGGEST
THERE WILL BE SOME POTENTIAL FOR A SHORT PERIOD OF GALES WED NIGHT.
WINDS SHIFT WNW FOR THU. WHILE WINDS WILL DIMINISH TO 15-25KT OVER
THE W...20-30KT WINDS WILL CONTINUE OVER THE E. WINDS WILL THEN
DIMINISH TO LIGHT (UNDER 15KT) FRI HAS HIGH PRES RIDGE ARRIVES. WINDS
SHOULD REMAIN UNDER 20KT SAT...BUT WITH UNCERTAINTY IN THE
STRENGTH/TRACK OF NEXT LOW PRES TRACKING E INTO THE GREAT LAKES...
WINDS COULD END UP STRONGER THAN CURRENTLY FCST.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...ROLFSON
AVIATION...KEC
MARINE...KC/ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
731 AM EDT TUE APR 2 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 520 AM EDT TUE APR 2 2013
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEP UPR TROF OVER
THE E HALF OF NAMERICA DOWNSTREAM OF RDG OVER WRN CANADA. CWA
REMAINS DOMINATED BY COLD CYC NW FLOW IN THE WAKE OF SLOWLY
DEPARTING CLOSED LO OVER WRN QUEBEC. ALTHOUGH H85 TEMPS RANGING FM
-14C OVER THE W TO -16C OVER THE E AND INVRN BASE NEAR H8 ARE
SUFFICIENTLY COLD/HI FOR LES EVEN IN THE ABSENCE OF ANY DYNAMIC
FORCING...UPSTREAM 00Z INL/YPL RAOBS ARE SO DRY...WITH THE H925
DEWPT DEPRESSION 15C AT INL IN INVERTED V T/TD PROFILE...THAT THERE
ONLY A FEW WEAK CLD BANDS OVER THE W HALF OF LK SUP STREAMING INTO
THE WRN ZNS. WITH A LONGER FETCH OVER THE E HALF AND A WEAK SFC TROF
PASSING THRU THIS AREA...MORE CLDS/SOME LES BANDS ARE EVIDENT
STREAMING INTO THE CWA E OF MQT. BUT DRYNESS OF AIRMASS IS EVIDENT
IN LO REFLECTIVITIES. LOOKING FARTHER UPSTREAM...THERE IS A FAIRLY
VIGOROUS SHRTWV NEAR LK WINNIPEG DIGGING SEWD. BUT SINCE THE 00Z THE
PAS MANITOBA RAOB IS ALSO QUITE DRY WITH INVERTED V T/TD PROFILE IN
THE LLVLS...THERE ARE ONLY SOME PATCHY MID/HI CLDS IN THE PVA
ASSOCIATED WITH THIS FEATURE. ANOTHER SHRTWV OVER HUDSON BAY IS
DIVING SWD.
EARLY THIS MRNG/TODAY...WITH NOCTURNAL COOLING EARLY THIS MRNG AND
SOME ENHANCED LLVL CNVGC ALONG WEAK SFC TROF...EXPECT SCT-NMRS -SHSN
TO IMPACT THE ERN ZNS THRU THIS MRNG. OVER THE W...THERE SHOULD BE
LTL IF ANY LES OR EVEN LK CLDS THRU 09Z GIVEN THE UPSTREAM
DRYNESS...BUT MODELS SHOW AREA OF DPVA/H85-5 QVECTOR CNVGC
ASSOCIATED WITH SHRTWV DIGGING THRU MN IMPACTING THE FAR W BY 12Z.
SUSPECT MORE CLDS/A FEW -SHSN MIGHT DVLP IN PRESENCE OF NOCTURNAL
COOLING...BUT LLVL DRYNESS WL LIMIT COVERAGE/INTENSITY OF ANY SHSN
THAT MIGHT POP UP. IF THERE IS ANY SHSN...THESE SHOULD DIMINISH ONCE
THE FORCING PASSES TO THE S BY 15Z AND DAYTIME HEATING BEGINS TO
DISRUPT THE LES PROCESS. LATE IN THE DAY...NEXT SHRTWV OVER HUDSON
BAY IS PROGGED TO DIG INTO THE UPR LKS WITH ACCOMPANYING DPVA AND
H85-5 QVECTOR CNVGC IMPACTING THE CWA. ALTHOUGH DAYTIME HEATING
MIGHT ALSO DISRUPT THE LES OVER THE E HALF IN THE AFTN...THE ARRIVAL
OF THIS FORCING MIGHT CAUSE AN UPTICK OF SHSN AGAIN TOWARD 00Z
ESPECIALLY OVER THE E HALF CLOSER TO DEEPER MSTR/COLDER AIR.
AS FOR TEMPS...PREFER TO TEND TOWARD THE HIER END OF GUIDANCE WITH A
GOOD DEAL OF SUNSHINE...AT LEAST OVER THE W AND SCENTRAL.
TNGT...SHRTWV DROPPING S INTO THE UPR LKS AND ACCOMPANYING DYNAMIC
FORCING IS PROGGED TO CROSS THE ERN COUNTIES. WITH LOWER H85 TEMPS
ARND -17C CLOSER TO THE CYC SIDE OF THE TRACK OF THIS DISTURBANCE AS
WELL AS DEEPER MSTR/SOMEWHAT HIER INVRN SHOWN THERE ON FCST SDNGS...
OPTED TO RAISE POPS INTO THE LIKELY RANGE NEAR LK SUP E OF MQT AS
THESE EVENTS OCCUR DURING THE MORE FAVORABLE NOCTURNAL COOLING.
EXPECT MUCH LESS IF ANY ACTIVITY OVER THE W ON THE ACYC SIDE OF THE
SHRTWV PASSAGE AND WHERE FCST SNDGS SHOW MUCH DRIER AIR AND HIER H85
TEMPS/LOWER INVNR BASE. EXPECT THE LOWEST MIN TEMPS TOWARD THE LOWER
END OF GUIDANCE OVER THE INTERIOR W UNDER THE DRIER AIR AND WHERE
WINDS WL BE LIGHTER.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 520 AM EDT TUE APR 2 2013
LOOKS LIKE A PATTERN CHANGE IS IN THE OFFING OVER THE NEXT FEW WEEKS
THAT WILL TRANSITION THE PERSISTENT BELOW NORMAL TEMP REGIME TOWARD
AN ABOVE NORMAL ONE. THE AO AND NAO WHICH HAVE BEEN IN A PREVAILING
NEGATIVE PHASE SINCE EARLY/MID FEB ARE BOTH FORECAST TO TREND TO THE
POSITIVE PHASE...WITH THE AO BECOMING STRONGLY POSITIVE. THIS
SUPPORTS A TREND TOWARD ABOVE NORMAL TEMPS HEADING INTO MID/LATE
APRIL...BUT THIS DOESN`T PRECLUDE THE POTENTIAL FOR MORE WINTRY PCPN
EVENTS BEFORE THE WARMER PATTERN SETS IN. THE PATTERN ALSO APPEARS
TO BE SHIFTING TOWARD AN ACTIVE ONE OVER THE NEXT 2 WEEKS. INTO THE
UPCOMING WEEKEND...FLOW WILL TREND PROGRESSIVE AND FLATTER WITH A
COUPLE OF SHORTWAVES TO AFFECT THE UPPER LAKES...THE FIRST WED
NIGHT/THU AND A SECOND MORE IMPORTANT WAVE SAT. EARLY NEXT WEEK...AN
AMPLIFIED TROF WILL BE DEVELOPING OVER THE WRN CONUS...SIGNALING THE
POTENTIAL FOR MORE SIGNIFICANT PCPN EVENTS NEXT WEEK FROM THE
CNTRL/SRN PLAINS TO THE GREAT LAKES AS THE GULF OPENS UP. THIS COULD
MEAN ONE OR MORE UNWELCOMED RAIN EVENTS ON A MELTING SNOWPACK WHICH
IS STILL DEEP IN THE LAKE EFFECT AREAS OR MORE SNOW COULD STILL BE
ADDED. IN RECENT DAYS...MEDIUM RANGE GUIDANCE HAS TONED DOWN THE
WARMING NEXT WEEK...SO MORE SNOW IS STILL A REAL POSSIBILITY.
BEGINNING WED...SFC HIGH PRES WILL QUICKLY SHIFT ACROSS THE WRN
GREAT LAKES AHEAD OF THE FIRST SHORTWAVE THAT WILL BE TRACKING
ACROSS SASKATCHEWAN/MANITOBA. IF ANY LIGHT LES IS LINGERING OVER THE
ERN FCST AREA TO START THE DAY...IT WILL END QUICKLY IN THE MORNING.
AFTER A PERIOD OF SUNSHINE...HIGH CLOUDS WILL BE ON THE INCREASE.
SUNSHINE WILL SUPPORT A STRONG DIURNAL TEMP SPREAD. AFTER MORNING
LOWS IN THE SINGLE DIGITS OVER THE INTERIOR W...TEMPS SHOULD REBOUND
INTO THE UPPER 30S/LWR 40S.
SHORTWAVE WILL MOVE ACROSS NRN ONTARIO WED NIGHT/THU MORNING. WITH
STRONG DEEP LAYER FORCING/IMPRESSIVE 500MB HEIGHT FALLS (AROUND
200M/12HR) PASSING WELL TO THE N OF HERE...MAIN PCPN AREA WILL PASS
TO THE N OF UPPER MI. NONETHELESS...50-80M HEIGHT FALLS AT 500MB...
RIBBON OF MODEST DEEP LAYER FORCING PER QVECTORS AND ISENTROPIC
ASCENT SUGGEST SOME PCPN POTENTIAL ACROSS THE FCST AREA. WITH
ISENTROPIC ASCENT WEAKENING AS IT SHIFTS ACROSS THE UPPER LAKES...
AND LOW-LEVEL DRY AIR TO OVERCOME INITIALLY...NOTHING MORE THAN LOW
CHC POPS APPEAR WARRANTED ATTM. ALTHOUGH LOW-LEVEL TEMPS ARE JUST
ABOVE 0C PRIOR TO POTENTIAL PCPN ARRIVING...EVAPORATIVE COOLING
SHOULD BE SUFFICIENT SO THAT SNOW BECOMES THE MAIN PTYPE IN MOST
AREAS. PCPN CHC WILL END W TO E THU MORNING WITH DRY WEATHER
FOLLOWING THRU THU NIGHT/FRI AS SFC HIGH PRES RIDGE BUILDS SE INTO
THE UPPER LAKES. 850MB TEMPS FALLING TO AROUND -12C THU NIGHT/FRI
MORNING WILL BE AT THE THRESHOLD FOR LES. HOWEVER...SINCE LOW-LEVEL
FLOW BECOMES MORE ANTICYCLONIC DURING THE NIGHT AND AIR MASS IS
FAIRLY DRY IN THE LOW-LEVELS...WILL NOT INCLUDE ANY MENTION OF
-SHSN. OVER THE W...FLOW IS MORE DIVERGENT...SO THERE MAY NOT EVEN
BE MUCH IN THE WAY OF CLOUDS. OPTED TO GO BLO GUIDANCE THERE THU
NIGHT AS WINDS WILL PROBABLY FALL OFF TO CALM AS HIGH PRES RIDGE
NEARS. ALTHOUGH LOWERED MINS TO THE LOW/MID TEENS...TEMPS COULD
EASILY FALL INTO THE SINGLE DIGITS.
FRI NIGHT/SAT...ATTENTION TURNS TO THE SECOND MORE IMPORTANT
SHORTWAVE TRACKING ACROSS THE NRN CONUS IN FLATTER FLOW REGIME.
MEDIUM RANGE GUIDANCE IS MOVING TOWARD SLIGHTLY BETTER AGREEMENT
WITH SYSTEM...BUT IMPORTANT DETAILS HAVE YET TO BE NARROWED DOWN.
THE GFS WHICH HAS BEEN CONSISTENTLY FARTHER S HAS TRENDED A LITTLE
FARTHER N WITH WAVE AND IS IN DECENT AGREEMENT WITH THE GLOBAL GEM.
THE ECMWF HAS BEEN CONSISTENTLY FARTHER N. THE GFS TRACK LOOKS TO
SUPPORT ALL SNOW FOR THE FCST AREA AS THE 850MB LOW TRACKS ALONG
WI/UPPER MI BORDER AND 850MB TEMPS REMAIN BLO 0C AND 1000-850MB
THICKNESS IS NO HIGHER THAN 1295M. THE GLOBAL GEM MOSTLY SUPPORTS
ALL SNOW WITH A POSSIBLE CHANGEOVER TO RAIN S AND SE...BUT ITS
SLOWER/MORE WRAPPED UP SYSTEM DOES NOT APPEAR TO FIT THE DEVELOPING
FLATTER FLOW REGIME. HOWEVER...THE 00Z ECMWF ALSO TRENDED MUCH
SLOWER AND SHARPER WITH SHORTWAVE...SO THIS MAY BE AN IMPORTANT
TREND TO MONITOR IN FUTURE MODEL RUNS. THE FARTHER N ECMWF SUGGESTS
MORE OF A MIXED PCPN EVENT WITH MORE SNOW THAN RAIN N AND MORE RAIN
THAN SNOW S. THE HEAVIEST SWATH OF PCPN PASSES ACROSS NRN UPPER MI
IN THE ECMWF...JUST S IN THE GFS AND CLIPS THE SRN FCST AREA IN THE
GLOBAL GEM. WHILE THE DETAILS OF SHORTWAVE TRACK...RESULTING PCPN
AREA AND THE ALL IMPORTANT TEMP PROFILE HAVE YET TO BE AGREED
UPON...WHAT IS A LITTLE MORE CERTAIN IS THAT THIS WAVE MAY BE A
RATHER IMPRESSIVE PCPN PRODUCER DESPITE THE FLATTER FLOW REGIME.
STRONG WAA IS NOTED BY ALL GUIDANCE WITH 850MB WINDS AROUND 50KT.
THE FRONTOGENESIS SIGNAL IS ALSO QUITE STRONG. PROXIMITY OF STEEP
MIDLEVEL LAPSE RATES NEAR THE SRN EDGE OF THE PCPN AREA SUGGESTS
THERE WILL PROBABLY BE SOME CONVECTION AS IS OFTEN SEEN WITH WAVES
RUNNING ALONG THE BAROCLINIC ZONE AT THIS TIME OF YEAR. IT WILL BE A
SYSTEM TO WATCH.
IN THE WAKE OF THE SAT SYSTEM...DRY WEATHER SHOULD FOLLOW FOR SUN
UNDER WEAK SFC HIGH PRES RIDGE...THOUGH IF THE SLOWER GLOBAL GEM AND
ECMWF ARE RIGHT...SOME PCPN COULD LINGER THRU AT LEAST PART OF SUN.
ATTENTION THEN TURNS TO THE SW FOR MON/TUE AS TROF AMPLIFIES INTO
THE WRN CONUS. AMPLIFYING TROF MAY SEND SEVERAL SHORTWAVES INTO THE
GREAT LAKES NEXT WEEK WITH THE FIRST PERHAPS AS SOON AS MON. AS
WOULD BE EXPECTED WITH A DEEPENING WRN TROF...MODELS ARE AND WILL
CONTINUE TO HAVE TROUBLE WITH TIMING AND PLACEMENT OF SHORTWAVES
EJECTING NE...SO THERE IS LITTLE CONFIDENCE RIGHT NOW IN THE PCPN
FCST MON/TUE. WITH GULF OPENING UP AHEAD OF THE LARGE SCALE WRN
TROF...ANY SHORTWAVES AFFECTING THE AREA COULD BE MDT/HVY PCPN
PRODUCERS NEXT WEEK...AND PCPN COULD BE SNOW FOR PORTIONS OF UPPER
MI.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 730 AM EDT TUE APR 2 2013
ALTHOUGH A LO PRES TROF WILL PASS THIS EVNG...EXPECT VFR CONDITIONS
AT THE TAF SITES THIS PERIOD WITH DRY LLVL AIR. WITH DAYTIME
HEATING...THERE WL BE A GUSTY NW WIND MUCH OF TODAY.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 520 AM EDT TUE APR 2 2013
WHERE THE PRES GRADIENT WILL BE SHARPER CLOSER TO DEPARTING LO PRES
IN SE CANADA...EXPECT NNW WINDS UP TO 30 KTS THRU TONIGHT OVER THE E
ALONG WITH FREEZING SPRAY. LIGHTER WINDS UP TO 20 KTS WILL PREVAIL
OVER THE W WHERE THE GRADIENT WILL BE WEAKER. AFTER A BRIEF PERIOD
OF LIGHT WINDS FOR A PORTION OF WED AS HIGH PRES QUICKLY PASSES...S
TO SW WINDS WILL QUICKLY RAMP UP TO 20-30KT WED AFTN/EVENING AHEAD OF
LOW PRES TRACKING E INTO NRN ONTARIO. ALTHOUGH LOW-LEVEL TEMP PROFILE
IS STABLE...HEALTHLY PRES FALLS PASSING ACROSS NRN ONTARIO SUGGEST
THERE WILL BE SOME POTENTIAL FOR A SHORT PERIOD OF GALES WED NIGHT.
WINDS SHIFT WNW FOR THU. WHILE WINDS WILL DIMINISH TO 15-25KT OVER
THE W...20-30KT WINDS WILL CONTINUE OVER THE E. WINDS WILL THEN
DIMINISH TO LIGHT (UNDER 15KT) FRI HAS HIGH PRES RIDGE ARRIVES. WINDS
SHOULD REMAIN UNDER 20KT SAT...BUT WITH UNCERTAINTY IN THE
STRENGTH/TRACK OF NEXT LOW PRES TRACKING E INTO THE GREAT LAKES...
WINDS COULD END UP STRONGER THAN CURRENTLY FCST.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...ROLFSON
AVIATION...KC
MARINE...KC/ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
524 AM EDT TUE APR 2 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 520 AM EDT TUE APR 2 2013
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEP UPR TROF OVER
THE E HALF OF NAMERICA DOWNSTREAM OF RDG OVER WRN CANADA. CWA
REMAINS DOMINATED BY COLD CYC NW FLOW IN THE WAKE OF SLOWLY
DEPARTING CLOSED LO OVER WRN QUEBEC. ALTHOUGH H85 TEMPS RANGING FM
-14C OVER THE W TO -16C OVER THE E AND INVRN BASE NEAR H8 ARE
SUFFICIENTLY COLD/HI FOR LES EVEN IN THE ABSENCE OF ANY DYNAMIC
FORCING...UPSTREAM 00Z INL/YPL RAOBS ARE SO DRY...WITH THE H925
DEWPT DEPRESSION 15C AT INL IN INVERTED V T/TD PROFILE...THAT THERE
ONLY A FEW WEAK CLD BANDS OVER THE W HALF OF LK SUP STREAMING INTO
THE WRN ZNS. WITH A LONGER FETCH OVER THE E HALF AND A WEAK SFC TROF
PASSING THRU THIS AREA...MORE CLDS/SOME LES BANDS ARE EVIDENT
STREAMING INTO THE CWA E OF MQT. BUT DRYNESS OF AIRMASS IS EVIDENT
IN LO REFLECTIVITIES. LOOKING FARTHER UPSTREAM...THERE IS A FAIRLY
VIGOROUS SHRTWV NEAR LK WINNIPEG DIGGING SEWD. BUT SINCE THE 00Z THE
PAS MANITOBA RAOB IS ALSO QUITE DRY WITH INVERTED V T/TD PROFILE IN
THE LLVLS...THERE ARE ONLY SOME PATCHY MID/HI CLDS IN THE PVA
ASSOCIATED WITH THIS FEATURE. ANOTHER SHRTWV OVER HUDSON BAY IS
DIVING SWD.
EARLY THIS MRNG/TODAY...WITH NOCTURNAL COOLING EARLY THIS MRNG AND
SOME ENHANCED LLVL CNVGC ALONG WEAK SFC TROF...EXPECT SCT-NMRS -SHSN
TO IMPACT THE ERN ZNS THRU THIS MRNG. OVER THE W...THERE SHOULD BE
LTL IF ANY LES OR EVEN LK CLDS THRU 09Z GIVEN THE UPSTREAM
DRYNESS...BUT MODELS SHOW AREA OF DPVA/H85-5 QVECTOR CNVGC
ASSOCIATED WITH SHRTWV DIGGING THRU MN IMPACTING THE FAR W BY 12Z.
SUSPECT MORE CLDS/A FEW -SHSN MIGHT DVLP IN PRESENCE OF NOCTURNAL
COOLING...BUT LLVL DRYNESS WL LIMIT COVERAGE/INTENSITY OF ANY SHSN
THAT MIGHT POP UP. IF THERE IS ANY SHSN...THESE SHOULD DIMINISH ONCE
THE FORCING PASSES TO THE S BY 15Z AND DAYTIME HEATING BEGINS TO
DISRUPT THE LES PROCESS. LATE IN THE DAY...NEXT SHRTWV OVER HUDSON
BAY IS PROGGED TO DIG INTO THE UPR LKS WITH ACCOMPANYING DPVA AND
H85-5 QVECTOR CNVGC IMPACTING THE CWA. ALTHOUGH DAYTIME HEATING
MIGHT ALSO DISRUPT THE LES OVER THE E HALF IN THE AFTN...THE ARRIVAL
OF THIS FORCING MIGHT CAUSE AN UPTICK OF SHSN AGAIN TOWARD 00Z
ESPECIALLY OVER THE E HALF CLOSER TO DEEPER MSTR/COLDER AIR.
AS FOR TEMPS...PREFER TO TEND TOWARD THE HIER END OF GUIDANCE WITH A
GOOD DEAL OF SUNSHINE...AT LEAST OVER THE W AND SCENTRAL.
TNGT...SHRTWV DROPPING S INTO THE UPR LKS AND ACCOMPANYING DYNAMIC
FORCING IS PROGGED TO CROSS THE ERN COUNTIES. WITH LOWER H85 TEMPS
ARND -17C CLOSER TO THE CYC SIDE OF THE TRACK OF THIS DISTURBANCE AS
WELL AS DEEPER MSTR/SOMEWHAT HIER INVRN SHOWN THERE ON FCST SDNGS...
OPTED TO RAISE POPS INTO THE LIKELY RANGE NEAR LK SUP E OF MQT AS
THESE EVENTS OCCUR DURING THE MORE FAVORABLE NOCTURNAL COOLING.
EXPECT MUCH LESS IF ANY ACTIVITY OVER THE W ON THE ACYC SIDE OF THE
SHRTWV PASSAGE AND WHERE FCST SNDGS SHOW MUCH DRIER AIR AND HIER H85
TEMPS/LOWER INVNR BASE. EXPECT THE LOWEST MIN TEMPS TOWARD THE LOWER
END OF GUIDANCE OVER THE INTERIOR W UNDER THE DRIER AIR AND WHERE
WINDS WL BE LIGHTER.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 520 AM EDT TUE APR 2 2013
LOOKS LIKE A PATTERN CHANGE IS IN THE OFFING OVER THE NEXT FEW WEEKS
THAT WILL TRANSITION THE PERSISTENT BELOW NORMAL TEMP REGIME TOWARD
AN ABOVE NORMAL ONE. THE AO AND NAO WHICH HAVE BEEN IN A PREVAILING
NEGATIVE PHASE SINCE EARLY/MID FEB ARE BOTH FORECAST TO TREND TO THE
POSITIVE PHASE...WITH THE AO BECOMING STRONGLY POSITIVE. THIS
SUPPORTS A TREND TOWARD ABOVE NORMAL TEMPS HEADING INTO MID/LATE
APRIL...BUT THIS DOESN`T PRECLUDE THE POTENTIAL FOR MORE WINTRY PCPN
EVENTS BEFORE THE WARMER PATTERN SETS IN. THE PATTERN ALSO APPEARS
TO BE SHIFTING TOWARD AN ACTIVE ONE OVER THE NEXT 2 WEEKS. INTO THE
UPCOMING WEEKEND...FLOW WILL TREND PROGRESSIVE AND FLATTER WITH A
COUPLE OF SHORTWAVES TO AFFECT THE UPPER LAKES...THE FIRST WED
NIGHT/THU AND A SECOND MORE IMPORTANT WAVE SAT. EARLY NEXT WEEK...AN
AMPLIFIED TROF WILL BE DEVELOPING OVER THE WRN CONUS...SIGNALING THE
POTENTIAL FOR MORE SIGNIFICANT PCPN EVENTS NEXT WEEK FROM THE
CNTRL/SRN PLAINS TO THE GREAT LAKES AS THE GULF OPENS UP. THIS COULD
MEAN ONE OR MORE UNWELCOMED RAIN EVENTS ON A MELTING SNOWPACK WHICH
IS STILL DEEP IN THE LAKE EFFECT AREAS OR MORE SNOW COULD STILL BE
ADDED. IN RECENT DAYS...MEDIUM RANGE GUIDANCE HAS TONED DOWN THE
WARMING NEXT WEEK...SO MORE SNOW IS STILL A REAL POSSIBILITY.
BEGINNING WED...SFC HIGH PRES WILL QUICKLY SHIFT ACROSS THE WRN
GREAT LAKES AHEAD OF THE FIRST SHORTWAVE THAT WILL BE TRACKING
ACROSS SASKATCHEWAN/MANITOBA. IF ANY LIGHT LES IS LINGERING OVER THE
ERN FCST AREA TO START THE DAY...IT WILL END QUICKLY IN THE MORNING.
AFTER A PERIOD OF SUNSHINE...HIGH CLOUDS WILL BE ON THE INCREASE.
SUNSHINE WILL SUPPORT A STRONG DIURNAL TEMP SPREAD. AFTER MORNING
LOWS IN THE SINGLE DIGITS OVER THE INTERIOR W...TEMPS SHOULD REBOUND
INTO THE UPPER 30S/LWR 40S.
SHORTWAVE WILL MOVE ACROSS NRN ONTARIO WED NIGHT/THU MORNING. WITH
STRONG DEEP LAYER FORCING/IMPRESSIVE 500MB HEIGHT FALLS (AROUND
200M/12HR) PASSING WELL TO THE N OF HERE...MAIN PCPN AREA WILL PASS
TO THE N OF UPPER MI. NONETHELESS...50-80M HEIGHT FALLS AT 500MB...
RIBBON OF MODEST DEEP LAYER FORCING PER QVECTORS AND ISENTROPIC
ASCENT SUGGEST SOME PCPN POTENTIAL ACROSS THE FCST AREA. WITH
ISENTROPIC ASCENT WEAKENING AS IT SHIFTS ACROSS THE UPPER LAKES...
AND LOW-LEVEL DRY AIR TO OVERCOME INITIALLY...NOTHING MORE THAN LOW
CHC POPS APPEAR WARRANTED ATTM. ALTHOUGH LOW-LEVEL TEMPS ARE JUST
ABOVE 0C PRIOR TO POTENTIAL PCPN ARRIVING...EVAPORATIVE COOLING
SHOULD BE SUFFICIENT SO THAT SNOW BECOMES THE MAIN PTYPE IN MOST
AREAS. PCPN CHC WILL END W TO E THU MORNING WITH DRY WEATHER
FOLLOWING THRU THU NIGHT/FRI AS SFC HIGH PRES RIDGE BUILDS SE INTO
THE UPPER LAKES. 850MB TEMPS FALLING TO AROUND -12C THU NIGHT/FRI
MORNING WILL BE AT THE THRESHOLD FOR LES. HOWEVER...SINCE LOW-LEVEL
FLOW BECOMES MORE ANTICYCLONIC DURING THE NIGHT AND AIR MASS IS
FAIRLY DRY IN THE LOW-LEVELS...WILL NOT INCLUDE ANY MENTION OF
-SHSN. OVER THE W...FLOW IS MORE DIVERGENT...SO THERE MAY NOT EVEN
BE MUCH IN THE WAY OF CLOUDS. OPTED TO GO BLO GUIDANCE THERE THU
NIGHT AS WINDS WILL PROBABLY FALL OFF TO CALM AS HIGH PRES RIDGE
NEARS. ALTHOUGH LOWERED MINS TO THE LOW/MID TEENS...TEMPS COULD
EASILY FALL INTO THE SINGLE DIGITS.
FRI NIGHT/SAT...ATTENTION TURNS TO THE SECOND MORE IMPORTANT
SHORTWAVE TRACKING ACROSS THE NRN CONUS IN FLATTER FLOW REGIME.
MEDIUM RANGE GUIDANCE IS MOVING TOWARD SLIGHTLY BETTER AGREEMENT
WITH SYSTEM...BUT IMPORTANT DETAILS HAVE YET TO BE NARROWED DOWN.
THE GFS WHICH HAS BEEN CONSISTENTLY FARTHER S HAS TRENDED A LITTLE
FARTHER N WITH WAVE AND IS IN DECENT AGREEMENT WITH THE GLOBAL GEM.
THE ECMWF HAS BEEN CONSISTENTLY FARTHER N. THE GFS TRACK LOOKS TO
SUPPORT ALL SNOW FOR THE FCST AREA AS THE 850MB LOW TRACKS ALONG
WI/UPPER MI BORDER AND 850MB TEMPS REMAIN BLO 0C AND 1000-850MB
THICKNESS IS NO HIGHER THAN 1295M. THE GLOBAL GEM MOSTLY SUPPORTS
ALL SNOW WITH A POSSIBLE CHANGEOVER TO RAIN S AND SE...BUT ITS
SLOWER/MORE WRAPPED UP SYSTEM DOES NOT APPEAR TO FIT THE DEVELOPING
FLATTER FLOW REGIME. HOWEVER...THE 00Z ECMWF ALSO TRENDED MUCH
SLOWER AND SHARPER WITH SHORTWAVE...SO THIS MAY BE AN IMPORTANT
TREND TO MONITOR IN FUTURE MODEL RUNS. THE FARTHER N ECMWF SUGGESTS
MORE OF A MIXED PCPN EVENT WITH MORE SNOW THAN RAIN N AND MORE RAIN
THAN SNOW S. THE HEAVIEST SWATH OF PCPN PASSES ACROSS NRN UPPER MI
IN THE ECMWF...JUST S IN THE GFS AND CLIPS THE SRN FCST AREA IN THE
GLOBAL GEM. WHILE THE DETAILS OF SHORTWAVE TRACK...RESULTING PCPN
AREA AND THE ALL IMPORTANT TEMP PROFILE HAVE YET TO BE AGREED
UPON...WHAT IS A LITTLE MORE CERTAIN IS THAT THIS WAVE MAY BE A
RATHER IMPRESSIVE PCPN PRODUCER DESPITE THE FLATTER FLOW REGIME.
STRONG WAA IS NOTED BY ALL GUIDANCE WITH 850MB WINDS AROUND 50KT.
THE FRONTOGENESIS SIGNAL IS ALSO QUITE STRONG. PROXIMITY OF STEEP
MIDLEVEL LAPSE RATES NEAR THE SRN EDGE OF THE PCPN AREA SUGGESTS
THERE WILL PROBABLY BE SOME CONVECTION AS IS OFTEN SEEN WITH WAVES
RUNNING ALONG THE BAROCLINIC ZONE AT THIS TIME OF YEAR. IT WILL BE A
SYSTEM TO WATCH.
IN THE WAKE OF THE SAT SYSTEM...DRY WEATHER SHOULD FOLLOW FOR SUN
UNDER WEAK SFC HIGH PRES RIDGE...THOUGH IF THE SLOWER GLOBAL GEM AND
ECMWF ARE RIGHT...SOME PCPN COULD LINGER THRU AT LEAST PART OF SUN.
ATTENTION THEN TURNS TO THE SW FOR MON/TUE AS TROF AMPLIFIES INTO
THE WRN CONUS. AMPLIFYING TROF MAY SEND SEVERAL SHORTWAVES INTO THE
GREAT LAKES NEXT WEEK WITH THE FIRST PERHAPS AS SOON AS MON. AS
WOULD BE EXPECTED WITH A DEEPENING WRN TROF...MODELS ARE AND WILL
CONTINUE TO HAVE TROUBLE WITH TIMING AND PLACEMENT OF SHORTWAVES
EJECTING NE...SO THERE IS LITTLE CONFIDENCE RIGHT NOW IN THE PCPN
FCST MON/TUE. WITH GULF OPENING UP AHEAD OF THE LARGE SCALE WRN
TROF...ANY SHORTWAVES AFFECTING THE AREA COULD BE MDT/HVY PCPN
PRODUCERS NEXT WEEK...AND PCPN COULD BE SNOW FOR PORTIONS OF UPPER
MI.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 812 PM EDT MON APR 1 2013
DRY AIR MOVING ACROSS LAKE SUPERIOR SHOULD HELP KEEP TAF SITES
MOSTLY CLEAR THROUGH THE EVENING HRS. A DISTURBANCE MOVING DOWN FM
CANADA COULD HELP GENERATE SOME LAKE CLOUDS AND FLURRIES LATE
TONIGHT INTO TUESDAY...ESPECIALLY AS WINDS OVER THE LAKE VEER NNW
ALLOWING FOR INCREASED LOW-LVL CONVERGENCE. EXPECT CIGS TO LOWER TO
MVFR AS ALL TAF SITES WITH SOME LIGHT -SHSN/FLURRIES. INCREASINGLY
ANTICYCLONIC AND DIFLUENT LOW-LVL FLOW BY 18Z TUE SHOULD ALLOW FOR
MVFR CLOUDS TO ERODE AND VFR CONDITIONS TO RETURN.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 520 AM EDT TUE APR 2 2013
WHERE THE PRES GRADIENT WILL BE SHARPER CLOSER TO DEPARTING LO PRES
IN SE CANADA...EXPECT NNW WINDS UP TO 30 KTS THRU TONIGHT OVER THE E
ALONG WITH FREEZING SPRAY. LIGHTER WINDS UP TO 20 KTS WILL PREVAIL
OVER THE W WHERE THE GRADIENT WILL BE WEAKER. AFTER A BRIEF PERIOD
OF LIGHT WINDS FOR A PORTION OF WED AS HIGH PRES QUICKLY PASSES...S
TO SW WINDS WILL QUICKLY RAMP UP TO 20-30KT WED AFTN/EVENING AHEAD OF
LOW PRES TRACKING E INTO NRN ONTARIO. ALTHOUGH LOW-LEVEL TEMP PROFILE
IS STABLE...HEALTHLY PRES FALLS PASSING ACROSS NRN ONTARIO SUGGEST
THERE WILL BE SOME POTENTIAL FOR A SHORT PERIOD OF GALES WED NIGHT.
WINDS SHIFT WNW FOR THU. WHILE WINDS WILL DIMINISH TO 15-25KT OVER
THE W...20-30KT WINDS WILL CONTINUE OVER THE E. WINDS WILL THEN
DIMINISH TO LIGHT (UNDER 15KT) FRI HAS HIGH PRES RIDGE ARRIVES. WINDS
SHOULD REMAIN UNDER 20KT SAT...BUT WITH UNCERTAINTY IN THE
STRENGTH/TRACK OF NEXT LOW PRES TRACKING E INTO THE GREAT LAKES...
WINDS COULD END UP STRONGER THAN CURRENTLY FCST.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...ROLFSON
AVIATION...VOSS
MARINE...KC/ROLFSON
AREA FORECAST DISCUSSION
NWS BILLINGS MT
923 PM MDT WED APR 3 2013
.SHORT TERM...VALID FOR THU AND FRI...
WEAK UPSLOPE FLOW AND ISENTROPIC LIFT HAS SET UP OVER THE ENTIRE
AREA THIS EVENING BEHIND A COLD FRONT THAT HAS MOVED WEST OF
LIVINGSTON. WEAK UPPER LEVEL SHORT WAVE CURRENTLY MOVING ACROSS
THE WEST ALONG WITH THE LEFT EXIT REGION OF THE UPPER LEVEL JET.
RADAR RETURNS DURING THE LAST HOUR HAVE INCREASED BUT SURFACE DEW
POINT TEMPERATURES REMAIN LOW AND MUCH OF THIS PRECIP IS NOT
HITTING THE GROUND. MODELS ARE OVERDONE WITH QPF VALUES TONIGHT
BUT THE RAP MODELS SEEMS TO BE THE BETTER MODEL AND WILL KEEP
ISOLATED POPS GOING FOR BILLINGS WEST FOR THE REMAINDER OF THE
EVENING. WILL KEEP SCATTERED POPS AFTER 06Z EAST OF BILLINGS. MET
GUIDANCE HAS COME IN WITH SLIGHTLY WARMER OVERNIGHT LOWS FOR
BILLINGS AND LIVINGSTON TONIGHT AND HAVE RAISED POPS A FEW DEGREES
FOR OVERNIGHT LOWS. ALSO MADE SOME WIND ADJUSTMENTS OVER SOUTHEAST
MONTANA. RICHMOND
.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...
FAIRLY ACTIVE AND SPRING-LIKE WEATHER PATTERN SHAPING UP FOR THE
EXTENDED PERIOD...THOUGH LATEST MODELS HAVE SHIFTED A BIT FOR THE
MON/TUE TIME FRAME.
SATURDAY STILL LOOKING FAIRLY QUIET WITH RIDGING BEHIND LATE
FRIDAY WAVE. HAVE REDUCED POPS FOR ALL BUT OUR WEST...WHICH
SHOULD BEGIN TO SEE INCREASED SHOWER ACTIVITY BY AFTERNOON...AND
PER WESTERLY DOWNSLOPE WINDS HAVE ALSO RAISED TEMPS A FEW DEGREES.
SHOULD SEE HIGHS INTO THE LOWER/MID 60S.
MODELS CONTINUE TO BE IN GOOD AGREEMENT WITH TIMING A SHORTWAVE
THROUGH THE REGION SATURDAY NIGHT. WITH INCREASING CONFIDENCE HAVE
RAISED POPS A BIT MORE...TO LIKELY IN CENTRAL AND EAST PARTS AWAY
FROM THE DOWNSLOPING WESTERN FOOTHILLS. AIRMASS LOOKS TO BE TOO
WARM FOR ANYTHING BUT RAIN SHOWERS AT OUR LOWER ELEVATIONS...WITH
A POSSIBLE EXCEPTION IN OUR FAR NE WHERE LOW LEVEL EAST WINDS MAY
KEEP 850MB TEMPS NEAR ZERO. SO WILL KEEP A RAIN/SNOW MIX WITH
JUST A LITTLE ACCUMULATION FROM MILES CITY TO BAKER...BUT THE
BETTER SNOW POTENTIAL REALLY SHOULD BE NORTH AND NORTHEAST OF OUR
CWA. SYSTEM WILL EXIT QUICKLY INTO THE DAKOTAS AROUND 12Z SUNDAY.
NEXT PACIFIC ENERGY WILL BEGIN TO INFLUENCE OUR WEST BY SUNDAY
AFTERNOON OR NIGHT...SOME TIMING ISSUES EXIST HERE. THEN...AS
PREVIOUSLY MENTIONED...MODELS ARE BEGINNING TO PAINT A DIFFERENT
PICTURE WITH EVOLUTION OF THIS SYSTEM INTO MON/TUE. FLOW IN THE
EASTERN PACIFIC NOW EXPECTED TO BE A BIT FLATTER...WITH
AMPLIFICATION OVER THE WESTERN CONUS SHIFTED A BIT EAST. THUS...
PER LATEST TRENDS...A LARGE CLOSED LOW OVER THE GREAT BASIN TO
4-CORNERS REGION NOW LOOKS LESS LIKELY...WHICH LEAVES A WNW FLOW
WITH LOWER HEIGHTS OVER OUR REGION AS ENERGY DRIVES TO THE CENTRAL
ROCKIES AND MIDDLE PLAINS. COULD STILL SEE SOME WET SNOW IMPACTS
IN OUR AREA SOMETIME IN THE SUNDAY NIGHT INTO TUESDAY TIME
FRAME...AND BOTH THE GFS AND EC SHOW 850MB TEMPS NEAR OR SLIGHTLY
BELOW ZERO...BUT OVERALL POTENTIAL APPEARS LOWER NOW. PROGRESSIVE
SHORTWAVE ENERGY IN LOW HEIGHT REGIME AND LOW LEVEL UPSLOPE FLOW
ALL COMBINE TO WARRANT ABOVE CLIMO POPS FOR US NONETHELESS. WILL
TAPER POPS TO BELOW CLIMO...SLIGHT CHANCE...BY WEDNESDAY AS MODEL
CONSENSUS IS FOR RISING HEIGHTS WITH RIDGE BEGINNING TO BUILD OVER
THE PAC NW BY THEN.
AS FOR TEMPERATURES...ABOVE NORMAL SATURDAY SHOULD COOL TO NEAR
NORMAL SUNDAY AND BELOW NORMAL MONDAY AND TUESDAY. COULD SEE A
RETURN TO NEAR OR ABOVE NORMAL TEMPS BY THE MIDDLE OF NEXT WEEK...
AND HAVE ADJUSTED GRIDS ACCORDINGLY.
JKL
&&
.AVIATION...
EXPECT ISOLATED TO SCATTERED SHOWERS TO LINGER ALONG A FRONTAL
BOUNDARY NEAR KLVM AND THE NEARBY FOOTHILLS THROUGH MIDNIGHT...WITH
DRYING ANTICIPATED AFTER MIDNIGHT. LOCALIZED MVFR IS POSSIBLE
WITH THE SHOWER ACTIVITY. VFR CONDITIONS WILL PREVAIL ACROSS THE
AREA LATE TONIGHT AND THURSDAY. CHURCH
&&
.PRELIMINARY POINT TEMP/POPS...
THU FRI SAT SUN MON TUE WED
-----------------------------------------------------------
BIL 035/064 043/064 038/063 038/057 032/046 029/048 030/056
20/B 37/T 32/W 52/W 35/W 42/W 22/W
LVM 034/064 039/058 033/061 031/055 029/044 028/046 028/055
21/B 26/T 24/W 53/W 35/J 32/W 22/W
HDN 033/065 041/068 038/065 036/059 031/047 029/049 028/054
20/B 37/T 32/W 62/W 35/W 42/W 22/W
MLS 032/057 038/067 038/061 035/055 029/045 027/045 026/049
22/W 24/T 31/B 62/W 24/W 42/W 22/W
4BQ 032/064 040/066 038/062 036/056 032/046 028/044 024/046
21/B 14/T 41/B 63/W 24/W 43/W 22/W
BHK 027/050 032/061 035/055 031/050 027/041 023/041 023/043
23/W 13/T 31/B 64/W 33/W 33/J 22/W
SHR 033/064 039/066 035/061 033/056 030/045 027/045 027/051
20/B 14/T 31/B 32/W 35/W 43/W 22/W
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
628 PM MDT WED APR 3 2013
.SHORT TERM...VALID FOR THU AND FRI...
QUICK UPDATE TO REMOVE LATE AFTERNOON WORDING FROM ZONES. RADAR
SHOWING ISOLATED SHOWERS OVER OUR WESTERN ZONES BUT THEY HAVE BEEN
DISSIPATING AS THEY PUSH EAST. WATER VAPOR SATELLITE INDICATING
DRIER AIR MOVING IN BEHIND THE CURRENT UPPER LEVEL WAVE MOVING
OVER OUR WESTERN ZONES. CURRENT FORECAST HAS THIS HANDLED WELL
WITH PRECIP ENDING LATE THIS EVENING. WILL DO ANOTHER UPDATE
AROUND 9 PM. RICHMOND
PREVIOUS DISCUSSION...
COLD FRONT HAD PUSHED THROUGH THE FRONT RANGE OF MONTANA BY EARLY
AFTERNOON AND IS CHUGGING ALONG PRETTY GOOD. I LIKE THE RAP MODELS
TIMING WHICH SWITCHES BILLINGS WINDS TO THE NORTHEAST LATE THIS
AFTERNOON AND SHERIDANS BY 8 PM. THE RAP ALSO BRINGS EASTERLY WIND
INTO LIVINGSTON AT THAT POINT...BUT WE ARE LESS CONFIDENT IN THIS
OCCURRING...AND BELIEVE THE COOLER AIR MIGHT STAY JUST EAST OF
LIVINGSTON DOORSTEP. AT ANY RATE MODELS ARE GENERATING DECENT
FRONTOGENESIS OVER OUR WESTERN ZONES LATE TODAY AND THERE APPEARS
TO BE SOME MODEST CONVECTION DEVELOPING JUST UPSTREAM OF THIS
AREA. SOME WEAK ENERGY CONTINUES TO MOVE ACROSS EAST CENTRAL
MONTANA OVERNIGHT...SO WILL CONTINUE TO INCLUDE SOME LOW POPS
AFTER MIDNIGHT.
THURSDAY OUR FORECAST AREA WILL GENERALLY BE BETWEEN SYSTEMS WITH
LOW AMPLITUDE RIDGING AND SURFACE TROUGHING DEVELOPING BEFORE
EVENING. THE MAIN WEATHER FEATURE THURSDAY WILL BE THE BACKING
UPPER FLOW BRINGING A NICE FETCH OF PACIFIC MOISTURE INTO THE
INNER ROCKIES. SO WE EXPECT INCREASING CLOUD COVER TO LIMIT
TEMPERATURES AND MIXING SOMEWHAT. BY THURSDAY NIGHT...WEAK ENERGY
INVOLVED WITH THAT MOISTURE FETCH MAY SPREAD SOME LIGHT SHOWERS
ACROSS THE REGION. HOWEVER THE MAIN PLAYER CONTINUES TO BE A LOW
AMPLITUDE SHORT WAVE PROGGED TO CROSS OUR FORECAST AREA FRIDAY.
MODELS AGREE THAT Q VECTOR FORCING WILL BE RIGHT OVER OUR ZONES
FRIDAY AFTERNOON WITH DECENT CAPE ON THE ORDER FROM 200-400 JL/KG.
I CONTINUED TO NUDGE THE POPS UP FOR FRIDAY AFTERNOON IN MANY
LOCATIONS AND WENT CATEGORICAL IN THE HIGH COUNTRY. THE GFS
LINGERS QPF OVER OUR FORECAST AREA WELL INTO FRIDAY NIGHT...BUT
THE OVERALL CONSENSUS OF MODELS GENERALLY EXIT THIS FORCING TO
THE EAST IN THE EVENING. THIS SEEMS MORE LIKELY GIVEN THE GOOD
CONVERGENT/DIVERGENT COUPLET...SO TRENDED OUR POPS LOWER
OVERNIGHT. BT
.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...
FAIRLY ACTIVE AND SPRING-LIKE WEATHER PATTERN SHAPING UP FOR THE
EXTENDED PERIOD...THOUGH LATEST MODELS HAVE SHIFTED A BIT FOR THE
MON/TUE TIME FRAME.
SATURDAY STILL LOOKING FAIRLY QUIET WITH RIDGING BEHIND LATE
FRIDAY WAVE. HAVE REDUCED POPS FOR ALL BUT OUR WEST...WHICH
SHOULD BEGIN TO SEE INCREASED SHOWER ACTIVITY BY AFTERNOON...AND
PER WESTERLY DOWNSLOPE WINDS HAVE ALSO RAISED TEMPS A FEW DEGREES.
SHOULD SEE HIGHS INTO THE LOWER/MID 60S.
MODELS CONTINUE TO BE IN GOOD AGREEMENT WITH TIMING A SHORTWAVE
THROUGH THE REGION SATURDAY NIGHT. WITH INCREASING CONFIDENCE HAVE
RAISED POPS A BIT MORE...TO LIKELY IN CENTRAL AND EAST PARTS AWAY
FROM THE DOWNSLOPING WESTERN FOOTHILLS. AIRMASS LOOKS TO BE TOO
WARM FOR ANYTHING BUT RAIN SHOWERS AT OUR LOWER ELEVATIONS...WITH
A POSSIBLE EXCEPTION IN OUR FAR NE WHERE LOW LEVEL EAST WINDS MAY
KEEP 850MB TEMPS NEAR ZERO. SO WILL KEEP A RAIN/SNOW MIX WITH
JUST A LITTLE ACCUMULATION FROM MILES CITY TO BAKER...BUT THE
BETTER SNOW POTENTIAL REALLY SHOULD BE NORTH AND NORTHEAST OF OUR
CWA. SYSTEM WILL EXIT QUICKLY INTO THE DAKOTAS AROUND 12Z SUNDAY.
NEXT PACIFIC ENERGY WILL BEGIN TO INFLUENCE OUR WEST BY SUNDAY
AFTERNOON OR NIGHT...SOME TIMING ISSUES EXIST HERE. THEN...AS
PREVIOUSLY MENTIONED...MODELS ARE BEGINNING TO PAINT A DIFFERENT
PICTURE WITH EVOLUTION OF THIS SYSTEM INTO MON/TUE. FLOW IN THE
EASTERN PACIFIC NOW EXPECTED TO BE A BIT FLATTER...WITH
AMPLIFICATION OVER THE WESTERN CONUS SHIFTED A BIT EAST. THUS...
PER LATEST TRENDS...A LARGE CLOSED LOW OVER THE GREAT BASIN TO
4-CORNERS REGION NOW LOOKS LESS LIKELY...WHICH LEAVES A WNW FLOW
WITH LOWER HEIGHTS OVER OUR REGION AS ENERGY DRIVES TO THE CENTRAL
ROCKIES AND MIDDLE PLAINS. COULD STILL SEE SOME WET SNOW IMPACTS
IN OUR AREA SOMETIME IN THE SUNDAY NIGHT INTO TUESDAY TIME
FRAME...AND BOTH THE GFS AND EC SHOW 850MB TEMPS NEAR OR SLIGHTLY
BELOW ZERO...BUT OVERALL POTENTIAL APPEARS LOWER NOW. PROGRESSIVE
SHORTWAVE ENERGY IN LOW HEIGHT REGIME AND LOW LEVEL UPSLOPE FLOW
ALL COMBINE TO WARRANT ABOVE CLIMO POPS FOR US NONETHELESS. WILL
TAPER POPS TO BELOW CLIMO...SLIGHT CHANCE...BY WEDNESDAY AS MODEL
CONSENSUS IS FOR RISING HEIGHTS WITH RIDGE BEGINNING TO BUILD OVER
THE PAC NW BY THEN.
AS FOR TEMPERATURES...ABOVE NORMAL SATURDAY SHOULD COOL TO NEAR
NORMAL SUNDAY AND BELOW NORMAL MONDAY AND TUESDAY. COULD SEE A
RETURN TO NEAR OR ABOVE NORMAL TEMPS BY THE MIDDLE OF NEXT WEEK...
AND HAVE ADJUSTED GRIDS ACCORDINGLY.
JKL
&&
.AVIATION...
A CANADIAN COLD FRONT IS PUSHING SOUTHWARD THROUGH THE AREA THIS
AFTERNOON...CAUSING GUSTY NW-N-NE WINDS ACROSS THE LOWER
ELEVATIONS...WITH GUSTS TO 25 KTS UNTIL SUNSET. EXPECT ISOLATED TO
SCATTERED SHOWERS TO DEVELOP ALONG THIS FRONTAL BOUNDARY FROM KLVM
TO KBIL AND KSHR THROUGH AROUND 04Z...WITH DRYING ANTICIPATED
LATER TONIGHT. LOCALIZED MVFR IS POSSIBLE WITH THE SHOWER
ACTIVITY. VFR CONDITIONS WILL PREVAIL ACROSS THE AREA LATE TONIGHT
AND THURSDAY. JKL
&&
.PRELIMINARY POINT TEMP/POPS...
THU FRI SAT SUN MON TUE WED
-----------------------------------------------------------
BIL 034/064 043/064 038/063 038/057 032/046 029/048 030/056
20/B 37/T 32/W 52/W 35/W 42/W 22/W
LVM 033/064 039/058 033/061 031/055 029/044 028/046 028/055
31/B 26/T 24/W 53/W 35/J 32/W 22/W
HDN 033/065 041/068 038/065 036/059 031/047 029/049 028/054
20/B 37/T 32/W 62/W 35/W 42/W 22/W
MLS 031/057 038/067 038/061 035/055 029/045 027/045 026/049
32/W 24/T 31/B 62/W 24/W 42/W 22/W
4BQ 031/064 040/066 038/062 036/056 032/046 028/044 024/046
21/B 14/T 41/B 63/W 24/W 43/W 22/W
BHK 027/050 032/061 035/055 031/050 027/041 023/041 023/043
33/W 13/T 31/B 64/W 33/W 33/J 22/W
SHR 032/064 039/066 035/061 033/056 030/045 027/045 027/051
20/B 14/T 31/B 32/W 35/W 43/W 22/W
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1238 PM CDT TUE APR 2 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 316 AM CDT TUE APR 2 2013
TODAY...THE HIGH PLAINS DISTURBANCE OPERATING ON LIMITED
MOISTURE WILL DRIFT VERY SLOWLY EAST SOUTHEAST TODAY AND TONIGHT.
GIVEN THE DRY AIR AT THE LOWER LEVELS...SPRINKLES LOOKED REASONABLE
ACROSS SWRN NEB. MID LEVEL CLOUDINESS WILL HANG ON TODAY AND TONIGHT
ACROSS THE SOUTHWEST. ELSEWHERE...MOSTLY CLEAR. A WEAK AREA FOR
FRONTOGENESIS HAS DEVELOPED ACROSS THE MISSOURI BASIN. THE RAP MODEL
IS LIFTING THIS FEATURE UP INTO THE MIDWEST TODAY.
OTHERWISE...A WARM FRONT SHOULD LIFT NORTH INTO THE SANDHILLS TODAY
WHILE WINDS NORTH OF THE FRONT BACK TO THE EAST AND NORTHEAST. FULL
SUN IN MANY AREAS SHOULD SEND HIGHS TO AROUND 60. THE RAP SUGGESTED
LOWER 60S IN MANY AREAS BUT THAT MODEL TENDS TO RUN WARM. RH DROPS
TO 20 TO 25 PERCENT THIS AFTERNOON BUT WINDS SHOULD REMAIN BELOW 15
MPH WITH WEAK WINDS CARRYING ALL THE WAY TO 700 MB.
TONIGHT...LOW PRESSURE DEVELOPS ACROSS THE NRN HIGH PLAINS WHICH
SETS UP A STRONGER SOUTHWEST WIND TONIGHT. THIS WILL HOLD LOWS
AROUND FREEZING.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 316 AM CDT TUE APR 2 2013
12Z WEDNESDAY AND BEYOND. MAIN FORECAST CONCERN GOING
IN THE EXTENDED PERIOD REVOLVES AROUND THE DEVELOPMENT OF AN
AMPLIFIED WESTERN CONUS TROUGH...WHICH MAY BRING PERIODS OF
WIDESPREAD PRECIPITATION BACK ACROSS THE CWA THIS WEEKEND AND
ESPECIALLY EARLY NEXT WEEK. BUT FIRST...AN UPPER LOW AND ATTENDANT
TROUGH THAT WILL BE POSITIONED ACROSS SOUTHEAST COLORADO/NORTHERN
NEW MEXICO EARLY WEDNESDAY WILL PROGRESS SOUTHEAST ACROSS TEXAS AND
THE SOUTHERN PLAINS THROUGH THURSDAY. THIS WILL ALLOW A TRANSITION
FROM SPLIT FLOW ALOFT OVER THE CENTRAL PLAINS...TO NORTHWESTERLY...AND
EVENTUALLY SOUTHWESTERLY AS A UPPER RIDGE BUILDS ACROSS THE PLAINS
ON FRIDAY. AT THE SAME TIME...AN UPPER TROUGH AND ATTENDANT LOW
WILL BE RAPIDLY PROGRESSING ACROSS THE CANADIAN ROCKIES TOWARD
SOUTHERN ONTARIO...DRAGGING A COLD FRONT THROUGH THE
NORTHERN/CENTRAL HIGH PLAINS EARLY ON THURSDAY. TEMPERATURES ON
WEDNESDAY WILL BE ATYPICAL...WITH THE WARMEST READINGS ACROSS
NORTHERN NEBRASKA...WHERE HIGHS IN THE LOW TO MID 60S SHOULD
PREVAIL. FOR SOUTHERN NEBRASKA...HIGHS ON WEDNESDAY WILL BE SOME
5-8F COOLER AS THE INFLUENCE OF THE SOUTHERN PLAINS UPPER LOW SHOULD
ALLOW FOR AN INCREASE CLOUDINESS AND SLIGHTLY COOLER TEMPERATURES
ALOFT. SLIGHTLY COOLER ACROSS THE NORTH ON THURSDAY AS MODIFIED
ARCTIC HIGH PRESSURE RECYCLES SOME COOLER AIR BACK INTO NORTH
CENTRAL NEBRASKA...ANTICIPATING HIGHS MAINLY IN THE MID 50S.
TEMPERATURES ACROSS THE SOUTH AND WEST WILL WARM SEVERAL DEGREES
UNDER FULL SUN AND WEAK WARMING ALOFT...MID 60S SHOULD PREVAIL.
FRIDAY WILL BE THE WARMEST DAY OF THE WEAK FOR ALL AREAS AS THE
UPPER RIDGE AXIS SHIFTS EAST ACROSS THE CWA. THERE MAY BE FIRE
CONCERNS AS SURFACE T/TDS SPREADS APPROACH 40F. SOUTHERLY WIND
SPEEDS LOOK TO INCREASE AS WELL AS A SURFACE TROUGH OF LOW PRESSURE
DEEPENS ACROSS THE HIGH PLAINS. BY EARLY SATURDAY...A WAVE WILL BE
PASSING THROUGH THE NORTHERN PLAINS WITHIN NEAR ZONAL FLOW
ALOFT...HOWEVER THE FORECAST MODELS SEEM TO BE KEYING ON MOST OF THE
QPF REMOVED FROM THE CWA...THUS WILL MAINTAIN THE INHERITED SLIGHT
CHANCE POPS FOR NOW AND NOT VENTURE ANY HIGHER. FOR SUNDAY AND
EARLY NEXT WEEK...THE LONG RANGE SOLUTIONS ALL ARRIVE AT A
SIGNIFICANT TROUGH ACROSS THE WESTERN CONUS...WITH THE POSSIBILITY
OF SEVERAL WAVES IMPACTING THE CWA...FIRST OF WHICH ARRIVES ON
SUNDAY. DIFFERENCES BETWEEN THE GFS AND EC ARE EVIDENT...MAINLY
WITH THE TIMING AND EVOLUTION OF THE MEAN WESTERN CONUS TROUGH...BUT
BOTH POINT TO A POTENTIALLY ACTIVE LATE WEEKEND/EARLY WORK WEEK SET
UP. BOTH ALSO INDICATE THE POTENTIAL OF A MYRIAD OF
PRECIPITATION...STARTING WITH TSTMS...SHOWERS...RAIN AND POSSIBLY
SNOW. WITH THE POTENTIAL SYSTEM STILL WAY OUT...DIDN/T WANT TO GET
TOO CUTE WITH PTYPE AND/OR LOCATIONS OF THE HIGHEST POPS. GENERALLY
BROAD-BRUSHED 30-40% POPS SUNDAY AND MONDAY...WITH SHOWERS POSSIBLY
CHANGING TO SNOW ACROSS THE NORTH LATE ON MONDAY...AND ACROSS THE
ENTIRE CWA EARLY TUESDAY MORNING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1238 PM CDT TUE APR 2 2013
NO AVIATION CONCERNS OVER THE NEXT 24 HOURS WITH VFR CONDITIONS
EXPECTED TO PREVAIL AT BOTH KLBF AND KVTN. WINDS WILL STRENGTHEN
OUT OF THE SOUTH TOMORROW MORNING...WITH WINDS GUSTING TO AROUND
20 KTS IN SOUTHERN NEBRASKA...TO AOA 25 KTS IN THE NORTH. CLOUD
COVER SHOULD GENERALLY STAY SOUTH OF THE AREA INTO KANSAS AND
COLORADO.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...MARTIN
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
620 AM CDT TUE APR 2 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 316 AM CDT TUE APR 2 2013
TODAY...THE HIGH PLAINS DISTURBANCE OPERATING ON LIMITED
MOISTURE WILL DRIFT VERY SLOWLY EAST SOUTHEAST TODAY AND TONIGHT.
GIVEN THE DRY AIR AT THE LOWER LEVELS...SPRINKLES LOOKED REASONABLE
ACROSS SWRN NEB. MID LEVEL CLOUDINESS WILL HANG ON TODAY AND TONIGHT
ACROSS THE SOUTHWEST. ELSEWHERE...MOSTLY CLEAR. A WEAK AREA FOR
FRONTOGENESIS HAS DEVELOPED ACROSS THE MISSOURI BASIN. THE RAP MODEL
IS LIFTING THIS FEATURE UP INTO THE MIDWEST TODAY.
OTHERWISE...A WARM FRONT SHOULD LIFT NORTH INTO THE SANDHILLS TODAY
WHILE WINDS NORTH OF THE FRONT BACK TO THE EAST AND NORTHEAST. FULL
SUN IN MANY AREAS SHOULD SEND HIGHS TO AROUND 60. THE RAP SUGGESTED
LOWER 60S IN MANY AREAS BUT THAT MODEL TENDS TO RUN WARM. RH DROPS
TO 20 TO 25 PERCENT THIS AFTERNOON BUT WINDS SHOULD REMAIN BELOW 15
MPH WITH WEAK WINDS CARRYING ALL THE WAY TO 700 MB.
TONIGHT...LOW PRESSURE DEVELOPS ACROSS THE NRN HIGH PLAINS WHICH
SETS UP A STRONGER SOUTHWEST WIND TONIGHT. THIS WILL HOLD LOWS
AROUND FREEZING.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 316 AM CDT TUE APR 2 2013
12Z WEDNESDAY AND BEYOND. MAIN FORECAST CONCERN GOING
IN THE EXTENDED PERIOD REVOLVES AROUND THE DEVELOPMENT OF AN
AMPLIFIED WESTERN CONUS TROUGH...WHICH MAY BRING PERIODS OF
WIDESPREAD PRECIPITATION BACK ACROSS THE CWA THIS WEEKEND AND
ESPECIALLY EARLY NEXT WEEK. BUT FIRST...AN UPPER LOW AND ATTENDANT
TROUGH THAT WILL BE POSITIONED ACROSS SOUTHEAST COLORADO/NORTHERN
NEW MEXICO EARLY WEDNESDAY WILL PROGRESS SOUTHEAST ACROSS TEXAS AND
THE SOUTHERN PLAINS THROUGH THURSDAY. THIS WILL ALLOW A TRANSITION
FROM SPLIT FLOW ALOFT OVER THE CENTRAL PLAINS...TO NORTHWESTERLY...AND
EVENTUALLY SOUTHWESTERLY AS A UPPER RIDGE BUILDS ACROSS THE PLAINS
ON FRIDAY. AT THE SAME TIME...AN UPPER TROUGH AND ATTENDANT LOW
WILL BE RAPIDLY PROGRESSING ACROSS THE CANADIAN ROCKIES TOWARD
SOUTHERN ONTARIO...DRAGGING A COLD FRONT THROUGH THE
NORTHERN/CENTRAL HIGH PLAINS EARLY ON THURSDAY. TEMPERATURES ON
WEDNESDAY WILL BE ATYPICAL...WITH THE WARMEST READINGS ACROSS
NORTHERN NEBRASKA...WHERE HIGHS IN THE LOW TO MID 60S SHOULD
PREVAIL. FOR SOUTHERN NEBRASKA...HIGHS ON WEDNESDAY WILL BE SOME
5-8F COOLER AS THE INFLUENCE OF THE SOUTHERN PLAINS UPPER LOW SHOULD
ALLOW FOR AN INCREASE CLOUDINESS AND SLIGHTLY COOLER TEMPERATURES
ALOFT. SLIGHTLY COOLER ACROSS THE NORTH ON THURSDAY AS MODIFIED
ARCTIC HIGH PRESSURE RECYCLES SOME COOLER AIR BACK INTO NORTH
CENTRAL NEBRASKA...ANTICIPATING HIGHS MAINLY IN THE MID 50S.
TEMPERATURES ACROSS THE SOUTH AND WEST WILL WARM SEVERAL DEGREES
UNDER FULL SUN AND WEAK WARMING ALOFT...MID 60S SHOULD PREVAIL.
FRIDAY WILL BE THE WARMEST DAY OF THE WEAK FOR ALL AREAS AS THE
UPPER RIDGE AXIS SHIFTS EAST ACROSS THE CWA. THERE MAY BE FIRE
CONCERNS AS SURFACE T/TDS SPREADS APPROACH 40F. SOUTHERLY WIND
SPEEDS LOOK TO INCREASE AS WELL AS A SURFACE TROUGH OF LOW PRESSURE
DEEPENS ACROSS THE HIGH PLAINS. BY EARLY SATURDAY...A WAVE WILL BE
PASSING THROUGH THE NORTHERN PLAINS WITHIN NEAR ZONAL FLOW
ALOFT...HOWEVER THE FORECAST MODELS SEEM TO BE KEYING ON MOST OF THE
QPF REMOVED FROM THE CWA...THUS WILL MAINTAIN THE INHERITED SLIGHT
CHANCE POPS FOR NOW AND NOT VENTURE ANY HIGHER. FOR SUNDAY AND
EARLY NEXT WEEK...THE LONG RANGE SOLUTIONS ALL ARRIVE AT A
SIGNIFICANT TROUGH ACROSS THE WESTERN CONUS...WITH THE POSSIBILITY
OF SEVERAL WAVES IMPACTING THE CWA...FIRST OF WHICH ARRIVES ON
SUNDAY. DIFFERENCES BETWEEN THE GFS AND EC ARE EVIDENT...MAINLY
WITH THE TIMING AND EVOLUTION OF THE MEAN WESTERN CONUS TROUGH...BUT
BOTH POINT TO A POTENTIALLY ACTIVE LATE WEEKEND/EARLY WORK WEEK SET
UP. BOTH ALSO INDICATE THE POTENTIAL OF A MYRIAD OF
PRECIPITATION...STARTING WITH TSTMS...SHOWERS...RAIN AND POSSIBLY
SNOW. WITH THE POTENTIAL SYSTEM STILL WAY OUT...DIDN/T WANT TO GET
TOO CUTE WITH PTYPE AND/OR LOCATIONS OF THE HIGHEST POPS. GENERALLY
BROAD-BRUSHED 30-40% POPS SUNDAY AND MONDAY...WITH SHOWERS POSSIBLY
CHANGING TO SNOW ACROSS THE NORTH LATE ON MONDAY...AND ACROSS THE
ENTIRE CWA EARLY TUESDAY MORNING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 620 AM CDT TUE APR 2 2013
VFR IS EXPECTED ALL AREAS TODAY AND TONIGHT. MIDLEVEL CLOUDINESS
ACROSS THE CNTL ROCKIES WILL SPREAD EAST TODAY AND TONIGHT
AFFECTING AREAS GENERALLY SOUTH OF INTERSTATE 80.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
316 AM CDT TUE APR 2 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 316 AM CDT TUE APR 2 2013
TODAY...THE HIGH PLAINS DISTURBANCE OPERATING ON LIMITED
MOISTURE WILL DRIFT VERY SLOWLY EAST SOUTHEAST TODAY AND TONIGHT.
GIVEN THE DRY AIR AT THE LOWER LEVELS...SPRINKLES LOOKED REASONABLE
ACROSS SWRN NEB. MID LEVEL CLOUDINESS WILL HANG ON TODAY AND TONIGHT
ACROSS THE SOUTHWEST. ELSEWHERE...MOSTLY CLEAR. A WEAK AREA FOR
FRONTOGENESIS HAS DEVELOPED ACROSS THE MISSOURI BASIN. THE RAP MODEL
IS LIFTING THIS FEATURE UP INTO THE MIDWEST TODAY.
OTHERWISE...A WARM FRONT SHOULD LIFT NORTH INTO THE SANDHILLS TODAY
WHILE WINDS NORTH OF THE FRONT BACK TO THE EAST AND NORTHEAST. FULL
SUN IN MANY AREAS SHOULD SEND HIGHS TO AROUND 60. THE RAP SUGGESTED
LOWER 60S IN MANY AREAS BUT THAT MODEL TENDS TO RUN WARM. RH DROPS
TO 20 TO 25 PERCENT THIS AFTERNOON BUT WINDS SHOULD REMAIN BELOW 15
MPH WITH WEAK WINDS CARRYING ALL THE WAY TO 700 MB.
TONIGHT...LOW PRESSURE DEVELOPS ACROSS THE NRN HIGH PLAINS WHICH
SETS UP A STRONGER SOUTHWEST WIND TONIGHT. THIS WILL HOLD LOWS
AROUND FREEZING.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 316 AM CDT TUE APR 2 2013
12Z WEDNESDAY AND BEYOND. MAIN FORECAST CONCERN GOING
IN THE EXTENDED PERIOD REVOLVES AROUND THE DEVELOPMENT OF AN
AMPLIFIED WESTERN CONUS TROUGH...WHICH MAY BRING PERIODS OF
WIDESPREAD PRECIPITATION BACK ACROSS THE CWA THIS WEEKEND AND
ESPECIALLY EARLY NEXT WEEK. BUT FIRST...AN UPPER LOW AND ATTENDANT
TROUGH THAT WILL BE POSITIONED ACROSS SOUTHEAST COLORADO/NORTHERN
NEW MEXICO EARLY WEDNESDAY WILL PROGRESS SOUTHEAST ACROSS TEXAS AND
THE SOUTHERN PLAINS THROUGH THURSDAY. THIS WILL ALLOW A TRANSITION
FROM SPLIT FLOW ALOFT OVER THE CENTRAL PLAINS...TO NORTHWESTERLY...AND
EVENTUALLY SOUTHWESTERLY AS A UPPER RIDGE BUILDS ACROSS THE PLAINS
ON FRIDAY. AT THE SAME TIME...AN UPPER TROUGH AND ATTENDANT LOW
WILL BE RAPIDLY PROGRESSING ACROSS THE CANADIAN ROCKIES TOWARD
SOUTHERN ONTARIO...DRAGGING A COLD FRONT THROUGH THE
NORTHERN/CENTRAL HIGH PLAINS EARLY ON THURSDAY. TEMPERATURES ON
WEDNESDAY WILL BE ATYPICAL...WITH THE WARMEST READINGS ACROSS
NORTHERN NEBRASKA...WHERE HIGHS IN THE LOW TO MID 60S SHOULD
PREVAIL. FOR SOUTHERN NEBRASKA...HIGHS ON WEDNESDAY WILL BE SOME
5-8F COOLER AS THE INFLUENCE OF THE SOUTHERN PLAINS UPPER LOW SHOULD
ALLOW FOR AN INCREASE CLOUDINESS AND SLIGHTLY COOLER TEMPERATURES
ALOFT. SLIGHTLY COOLER ACROSS THE NORTH ON THURSDAY AS MODIFIED
ARCTIC HIGH PRESSURE RECYCLES SOME COOLER AIR BACK INTO NORTH
CENTRAL NEBRASKA...ANTICIPATING HIGHS MAINLY IN THE MID 50S.
TEMPERATURES ACROSS THE SOUTH AND WEST WILL WARM SEVERAL DEGREES
UNDER FULL SUN AND WEAK WARMING ALOFT...MID 60S SHOULD PREVAIL.
FRIDAY WILL BE THE WARMEST DAY OF THE WEAK FOR ALL AREAS AS THE
UPPER RIDGE AXIS SHIFTS EAST ACROSS THE CWA. THERE MAY BE FIRE
CONCERNS AS SURFACE T/TDS SPREADS APPROACH 40F. SOUTHERLY WIND
SPEEDS LOOK TO INCREASE AS WELL AS A SURFACE TROUGH OF LOW PRESSURE
DEEPENS ACROSS THE HIGH PLAINS. BY EARLY SATURDAY...A WAVE WILL BE
PASSING THROUGH THE NORTHERN PLAINS WITHIN NEAR ZONAL FLOW
ALOFT...HOWEVER THE FORECAST MODELS SEEM TO BE KEYING ON MOST OF THE
QPF REMOVED FROM THE CWA...THUS WILL MAINTAIN THE INHERITED SLIGHT
CHANCE POPS FOR NOW AND NOT VENTURE ANY HIGHER. FOR SUNDAY AND
EARLY NEXT WEEK...THE LONG RANGE SOLUTIONS ALL ARRIVE AT A
SIGNIFICANT TROUGH ACROSS THE WESTERN CONUS...WITH THE POSSIBILITY
OF SEVERAL WAVES IMPACTING THE CWA...FIRST OF WHICH ARRIVES ON
SUNDAY. DIFFERENCES BETWEEN THE GFS AND EC ARE EVIDENT...MAINLY
WITH THE TIMING AND EVOLUTION OF THE MEAN WESTERN CONUS TROUGH...BUT
BOTH POINT TO A POTENTIALLY ACTIVE LATE WEEKEND/EARLY WORK WEEK SET
UP. BOTH ALSO INDICATE THE POTENTIAL OF A MYRIAD OF
PRECIPITATION...STARTING WITH TSTMS...SHOWERS...RAIN AND POSSIBLY
SNOW. WITH THE POTENTIAL SYSTEM STILL WAY OUT...DIDN/T WANT TO GET
TOO CUTE WITH PTYPE AND/OR LOCATIONS OF THE HIGHEST POPS. GENERALLY
BROAD-BRUSHED 30-40% POPS SUNDAY AND MONDAY...WITH SHOWERS POSSIBLY
CHANGING TO SNOW ACROSS THE NORTH LATE ON MONDAY...AND ACROSS THE
ENTIRE CWA EARLY TUESDAY MORNING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1241 AM CDT TUE APR 2 2013
UNLIMITED CEILING AND VISIBILITY CAN BE EXPECTED TONIGHT THROUGH
LATE TUESDAY EVENING IN CENTRAL AND WESTERN NEBRASKA. EVEN WITH
LIGHT EAST TO SOUTHEAST WIND...MOISTURE IS CONFINED TO VERY NEAR THE
SURFACE...AS CAN BE SEEN IN THE LBF SOUNDING...AND IS NOT LIKELY TO
HAVE ENOUGH DEPTH FOR THE FORMATION OF FOG.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
325 AM CDT TUE APR 2 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 324 AM CDT TUE APR 2 2013
FORECAST CHALLENGE CONCERNS MAINLY CLOUD TRENDS AND TEMPERATURES.
MODELS CLOSE IN THE SHORT TERM AND WILL BLEND. WEAK SHORT WAVE TO
DROP THROUGH MID LEVEL NORTHERLY FLOW TODAY. SATELLITE IMAGERY
INDICATING MOST ORGANIZED CLOUD COVER WITH WAVE TO DROP THROUGH
WESTERN/CENTRAL ND. WITH SURFACE HIGH PRESSURE IN PLACE WILL
MAINTAIN DRY FORECAST. WILL SEE SOME CLOUD COVER MAINLY FIRST HALF
OF THE DAY THEN MORE SOLAR. COLUMN DOES WARM A TAD BUT WITH EARLY
CLOUDS FEEL TEMPERATURES WILL TURN OUT FAIRLY CLOSE TO YESTERDAY.
AS SURFACE HIGH SHIFTS EAST TONIGHT WILL SEE INCREASED MIXING AND
WARM ADVECTION. THIS WILL HOLD TEMPERATURES UP WITH COOLEST AREAS
ACROSS THE FAR EAST WHICH WILL BE THE LAST AREA TO SEE ABOVE
CONDITIONS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 324 AM CDT TUE APR 2 2013
NEXT COLD FRONT TO DROP THROUGH FA WEDNESDAY. BASED ON TIMING OF
BOUNDARY AT THIS POINT APPEARS THAT WHAT PCPN DOES OCCUR SHOULD
INITIALLY BE LT RAIN WITH SOME PHASE ISSUES POSSIBLE DURING THE
EVENING ACROSS THE NORTHERN FA. MODELS SHOWING DIFFERENCES ON
THERMAL FIELDS AND PCPN POTENTIAL SO DID NOT MAKE ANY SIGNIFICANT
CHANGES. LOOKS TO BE THE WARMEST DAY OF THE WEEK WITH CLOUD TRENDS
INFLUENCING JUST HOW WARM WE GET. PCPN SHOULD WIND DOWN FROM WEST
TO EAST DURING THE EVENING. HIGH PRESSURE BUILDS IN THURSDAY FOR
DRY BUT COOLER TEMPERATURES.
FOCUS WILL BE ON THE EASTERN PACIFIC WAVE THAT MOVES ACROSS THE
NORTHERN TIER STATES FRIDAY AND SATURDAY. MODEL CONSENSUS IS STILL
POOR WITH THE 00 UTC ECMWF STILL FARTHER NORTH...WARMER AND SLOWER
COMPARED TO THE GFS...WHICH IS MORE SIMILAR TO THE DGEX AND GEM.
STILL BEING 3 TO 4 DAYS OUT...WILL FAVOR A BLENDED SOLUTION...WHICH
PLACES BEST CHANCE FOR ACCUMULATING PRECIPITATION (RAIN/SNOW MIX)
ACROSS THE SOUTHERN FORECAST AREA WHERE 0.5 TO 0.75 INCHES LIQUID
EQUIVALENT IS POSSIBLE. THE GFS SOLUTION WOULD RESULT IN MORE
SNOW...WHEREAS THE WARMER ECMWF WOULD BE MOSTLY RAIN. SUNDAY SHOULD
BE MOSTLY DRY WITH ANOTHER SHOT OF PRECIPITATION ON MONDAY IN
ADVANCE OF THE NEXT UPPER LOW DIGGING ACROSS THE CENTRAL ROCKIES.
DAY-TO-DAY TEMPERATURE CHANGES WILL BE MINIMAL WITH DAYTIME HIGHS IN
THE 30S TO LOWER 40S AND NIGHTTIME LOWS IN THE 20S TO LOWER 30S.
OVERALL...NO MAJOR AIR MASS CHANGES IN THE NEXT SEVEN DAYS...KEEPING
TEMPERATURES WELL BELOW EARLY APRIL NORMALS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1150 PM CDT MON APR 1 2013
THERE IS A WEAK SHORTWAVE THAT WILL PASS THROUGH THE REGION
OVERNIGHT AND INCREASE CLOUD COVER. NOT SURE HOW WIDESPREAD THE
CLOUDS WILL BE...OR EXACTLY HOW LOW. JUDGING FROM UPSTREAM
SATELLITE IMAGERY AND RAP GUIDANCE...THERE WILL LIKELY BE A PERIOD
OF BKN CIGS IN THE LOW VFR RANGE (ESPECIALLY ALONG AND WEST OF THE
RED RIVER VALLEY).
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...VOELKER
LONG TERM...ROGERS
AVIATION...TG
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1248 AM CDT TUE APR 2 2013
.UPDATE...
ISSUED AT 1247 AM CDT TUE APR 2 2013
NO SIGNIFICANT CHANGES WERE REQUIRED WITH THIS FORECAST UPDATE AS
THE INHERITED FORECAST FOR THE REMAINDER OF THE NIGHT IS WELL ON
TRACK AND BLENDED TO OBSERVED TRENDS THROUGH 530 UTC. THE ONLY
QUESTION FOR THE REMAINDER OF THE NIGHT IS HOW FAR INTO NORTHERN
NORTH DAKOTA EXPANDING STRATUS IN SOUTHEAST SASKATCHEWAN WILL BE
ABLE TO REACH. WILL FOLLOW CLOSELY TO THE 04 UTC RAP FOR LOW LEVEL
MOISTURE FIELDS FOR THE REMAINDER OF THE NIGHT AS IT CURRENTLY HAS
A GOOD DEPICTION OF THE STRATUS FIELD.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 346 PM CDT MON APR 1 2013
HIGH PRESSURE WILL GRADUALLY SHIFT EAST OF THE REGION THROUGH THE
PERIOD. DRY CONDITIONS WILL PREVAIL AS A RESULT. BELOW NORMAL
TEMPERATURES WILL CONTINUE THIS AFTERNOON AND TONIGHT.
HOWEVER...RETURN FLOW DEVELOPING ACROSS THE REGION COMBINED WITH NO
SNOW PACK SOUTHWEST OF THE MISSOURI WILL ALLOW TUESDAY AFTERNOON
HIGHS TO BE ABOVE NORMAL SOUTHWEST. BELOW NORMAL TEMPERATURES WILL
CONTINUE NORTH AND EAST OF THE MISSOURI RIVER...WHERE THE SNOW PACK
IS LOCATED.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 346 PM CDT MON APR 1 2013
THE MAIN FORECAST CHALLENGES FOR THE EXTENDED PERIOD INCLUDE
PRECIPITATION CHANCES AND PRECIPITATION TYPE. 12Z SUITE OF MODEL
SOLUTIONS ARE IN AGREEMENT EARLY IN THE PERIOD...WITH SOLUTIONS
DIVERGING LATE THIS WEEK.
WARM AIR ADVECTION WILL CONTINUE ACROSS THE AREA TUESDAY NIGHT AND
WEDNESDAY AHEAD OF A UPPER LEVEL WAVE/SURFACE LOW PRESSURE SYSTEM
THAT IS FORECAST TO PASS OVER NORTH DAKOTA. WARM H850
TEMPERATURES OF +6 TO +10C WILL BE FIRMLY IN PLACE WEDNESDAY AS
PRECIPITATION BEGINS ACROSS THE NORTHWEST AND SPREADS SOUTHEAST
ACROSS THE AREA WEDNESDAY. PRECIPITATION WILL BEGIN AS LIGHT
FREEZING RAIN AND TRANSITION TO LIGHT RAIN DURING WEDNESDAY
AFTERNOON. ACROSS THE SOUTHWEST...ISOLATED WEAK THUNDERSTORMS ARE
POSSIBLE...WHERE TEMPERATURES WILL BE IN THE 60S WITH SURFACE BASED
CAPE IN THE 100 TO 200 J/KG ADVERTISED BY THE 12Z NAM. BEFORE
ENDING WEDNESDAY EVENING...A TRANSITION FROM LIGHT RAIN TO A
WINTRY MIX OF SNOW...FREEZING RAIN...AND POSSIBLY SLEET WILL BE
SEEN AS A COLD FRONT MOVES SOUTH FROM CANADA.
COOLER TEMPERATURES WILL BE SEEN WEDNESDAY NIGHT AND THURSDAY...AS
COLD AIR COMMENCES FOLLOWING THE PASSAGE OF THE AFOREMENTIONED
COLD FRONT. HOWEVER...ACROSS THE SNOW LESS AREAS...TEMPERATURES
WILL BE WARMEST WITH TEMPERATURES IN 50S ON THURSDAY. FOR
LOCATIONS ACROSS THE SNOWPACK...TEMPERATURES WILL BE IN THE LOW TO
MID 30S.
STARTING FRIDAY...AN ACTIVE PERIOD OF WEATHER IS EXPECTED
TO START AS A SERIES OF UPPER LEVEL WAVES AND THEIR SURFACE
REFLECTIONS ARE PROGGED TO MOVE ACROSS THE AREA IN NORTHWESTERLY
FLOW. UNCERTAINTY REMAINS IN THE PLACEMENT AND TYPE OF
PRECIPITATION ACROSS NORTH DAKOTA...AS THERE IS DISAGREEMENT
AMONGST THE 12Z MODEL SOLUTIONS. THE 12Z GEM/GFS ARE MORE
AGGRESSIVE WITH QPF ACROSS THE WEST AND CENTRAL VERSUS THE 12Z EC
SOLUTION. THE 12Z EC KEEPS THE BULK OF THE PRECIPITATION FURTHER
NORTH ACROSS SOUTHERN MANITOBA AND SASKATCHEWAN.
AT THIS TIME HAVE UTILIZED A BLEND OF MODEL SOLUTIONS DURING THE
FRIDAY TO MONDAY PERIOD...WHICH GIVE A WIDE ARRAY OF PRECIPITATION
TYPES. AT THIS MOMENT...IT LOOKS LIKE THE SOUTHWEST WILL REMAIN
MOSTLY RAIN AS IT REMAINS IN THE WARM H850 TEMPERATURES OF +4 TO
+8 C. ELSEWHERE...A LIGHT WINTRY MIX OF SNOW...FREEZING RAIN...AND
POSSIBLY SLEET MAY OCCUR. BY SUNDAY EVENING AND
MONDAY...PRECIPITATION TYPE WILL BE SNOW...AS ANOTHER COLD FRONT
DROPS SOUTH OUT OF CANADA. FOLLOWING THE PASSAGE OF THE COLD
FRONT...COLDER H850 TEMPERATURES OF -8 TO -12 C ARE POSSIBLE AT
THE BEGINNING OF NEXT WEEK...AS A SURFACE HIGH PRESSURE STARTS TO
MOVE SOUTH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)...
ISSUED AT 1247 AM CDT TUE APR 2 2013
VFR CONDITIONS ARE FORECAST FOR THE 06 UTC TAF PERIOD ACROSS
WESTERN AND CENTRAL NORTH DAKOTA WITH HIGH PRESSURE IN PLACE.
THERE IS THE POTENTIAL THAT AN EXPANDING STRATUS FIELD ACROSS
SOUTHEAST SASKATCHEWAN AS OF 530 UTC MAY APPROACH THE KMOT
TERMINAL. DUE TO UNCERTAINTY CODED AS A TEMPO GROUP FOR MVFR
CEILINGS BETWEEN 8 AND 11 UTC AND WILL MONITOR SATELLITE TRENDS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...TM
LONG TERM...LTH
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1150 PM CDT MON APR 1 2013
.UPDATE...
ISSUED AT 1150 PM CDT MON APR 1 2013
NO UPDATE NEEDED AT THIS POINT AS CURRENT FORECAST IS ON TRACK
WITH PREVIOUS THINKING (SEE 945 PM UPDATE).
UPDATE ISSUED AT 945 PM CDT MON APR 1 2013
SHORTWAVE AND ASSOCIATED CLOUDS CONTINUE TO APPROACH THE REGION
FROM THE NORTHWEST. TIMED CLOUDY SKIES INTO THE FA BY LATER
TONIGHT AND INTO TUESDAY MORNING. SOME FLURRIES REPORTED
UPSTREAM...BUT MODELS DRY THIS ACTIVITY AS IT APPROACHES. NO
CHANGES NEEDED TO MIN TEMPS AS ANY CLOUD COVER WILL ARRIVE WELL
AFTER MIDNIGHT. MINOR ADJUSTMENTS TO THE HOURLY TEMPERATURE GRIDS
ACROSS THE FAR NW FA TO ACCOUNT FOR CLOUDS ARRIVING JUST BEFORE
SUNRISE.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 317 PM CDT MON APR 1 2013
TONIGHT...MAIN FORECAST CHALLENGE WILL BE CLOUDS AND TEMPS.
MODELS SEEM TO BE IN FAIR AGREEMENT SO WILL CONTINUE TO USE A
MODEL BLEND. NEVER SAW MUCH FOR CLOUD DEVELOPMENT TODAY SO WILL
START OFF THE NIGHT NEARLY CLOUD FREE. THERE IS AN UPSTREAM WAVE
OVER CENTRAL SASKATCHEWAN WITH SOME CLOUDS AND EVEN SOME FLURRIES
OR LIGHT SNOW ASSOCIATED WITH IT. AMERICAN MODELS HAD BEEN TRYING
TO HOLD SOME OF THIS LIGHT PCPN TOGETHER ALL THE WAY INTO THE
NORTHERN FA LATE. 12Z RUNS OF THE NAM/GFS STILL HOLD IT TOGETHER
BUT SEEM TO ERODE IT EITHER BEFORE IT GETS INTO OUR FA...WHILE
THE ECMWF REMAINS DRY. THEREFORE WILL KEEP THE FORECAST DRY
TONIGHT. AS FAR AS TEMPS GO SFC HIGH PRESSURE STILL REMAINS OVER
THE FA WITH SOME PRETTY LIGHT WINDS. WILL STICK WITH LOWS TONIGHT
FAIRLY SIMILAR TO THOSE FROM THIS MORNING.
TUE...SFC HIGH REMAINS IN CLOSE PROXIMITY TO THE RED RIVER VALLEY
KEEPING WINDS ON THE LOW SIDE AGAIN. LINGERING CLOUD COVER MAY
HAVE SOME INFLUENCE ON HIGHS FOR THE DAY. GENERALLY KEPT HIGHS
ABOUT 5F WARMER THAN TODAY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 317 PM CDT MON APR 1 2013
TUE NIGHT-THU...WED IS STILL ON TRACK TO BE THE WARMEST DAY OF THE
WEEK WITH 850MB TEMPS REACHING UP INTO THE +6C TO +8C RANGE OVER
PORTIONS OF THE FA WITH A LITTLE STEADIER SOUTH WINDS. MAYBE NOT
THE BEST DIRECTION FOR REALLY GOOD WARMING BUT AS THE COLD FRONT
COMES THRU THEY SHOULD SWITCH TO THE WEST THEN NW. STILL LOOKS
LIKE A LITTLE BIT OF PCPN WILL COME THROUGH WITH THE COLD FRONT
BUT TRIED TO NARROW DOWN THE WINDOW A BIT BETTER. SHOULD REALLY BE
A QUICK SHOT ALONG THE FRONT AND TEMPS SHOULD BE WARM ENOUGH TO
KEEP ANY PCPN IN THE LIQUID FORM UNLESS MORE PCPN LINGERS BEHIND
THE FRONT. THU WOULD BE COOLER BEHIND THE FRONT.
THU NIGHT-MON...AN ENERGETIC JET STREAM WITH SOMEWHAT FLATTENED
LONGWAVE RIDGE PATTERN IN THE LATE WEEK THEN TRANSITIONS TO A
BROAD WESTERN TROF OVER THE WEEKEND. THIS PRODUCES A BRIEF RETURN
TO NORTHWEST MID LEVEL FLOW OVER THE AREA ON THURSDAY AND A SUBTLE
/FEW DEGREE/ COOL DOWN BEHIND A SURFACE COLD FRONT. A RETURN
SOUTHERLY BLAYER FLOW IS EXPECTED ON FRIDAY... WITH ALL LONG RANGE
MODELS ANTICIPATING THE ADVANCE OF A COLORADO LOW INTO THE CENTRAL
AND NORTHERN PLAINS BY SATURDAY. A RAIN/SNOW MIX LOOKS QUITE
PROBABLE FOR MUCH OF THE AREA FROM FRIDAY EVENING INTO SATURDAY...
WITH A SOMEWHAT COOLER AND DRIER PATTERN ON SUNDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1150 PM CDT MON APR 1 2013
THERE IS A WEAK SHORTWAVE THAT WILL PASS THROUGH THE REGION
OVERNIGHT AND INCREASE CLOUD COVER. NOT SURE HOW WIDESPREAD THE
CLOUDS WILL BE...OR EXACTLY HOW LOW. JUDGING FROM UPSTREAM
SATELLITE IMAGERY AND RAP GUIDANCE...THERE WILL LIKELY BE A PERIOD
OF BKN CIGS IN THE LOW VFR RANGE (ESPECIALLY ALONG AND WEST OF THE
RED RIVER VALLEY).
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...TG
SHORT TERM...GODON
LONG TERM...GUST
AVIATION...TG
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
1223 AM CDT TUE APR 2 2013
.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
&&
.AVIATION...CIG MAY BE A BIT INTERMITTENT NEAR THE COAST BUT A
PREDOMINANT MVFR LAYER AT ABOUT 1100 TO 1300 FT IS EXPECTED FOR
THE NEXT FEW HOURS. NEAR THE COAST TEMPORARY DROPS TO ABOUT 800FT
WILL BE POSSIBLE AROUND SUNRISE. MVFR CIGS NEAR THE COAST THROUGH
MOST OF THE MORNING HOURS LIKELY SCATTERING OUT IN THE AFTERNOON.
VFR WILL OCCUR EARLIER INLAND. WINDS WILL BE MODERATE OUT OF THE
EAST TO SOUTHEAST. THERE IS A SMALL CHANCE FOR SHOWERS OR
THUNDERSTORMS...MAINLY OVER THE BRUSH COUNTRY BUT LEFT THOSE OUT
OF THE TAFS FOR NOW. LOWERING CIGS EXPECTED AGAIN TUESDAY NIGHT. /68-JGG/
&&
.PREV DISCUSSION... /ISSUED 208 PM CDT MON APR 1 2013/
SHORT TERM /NOW THROUGH TUESDAY NIGHT/...THE AREA REMAINS IN
QUASI-ZONAL FLOW ALOFT WITH AN UPPER LEVEL TROUGH LOCATED OVER THE
GREAT BASIN AND A WEAK IMPULSE RIDING WESTERLY FLOW IN NORTHERN
MEXICO SOUTH OF THE TEXAS BIG BEND. AT THE SURFACE...SOUTHEASTERLY
FLOW CONTINUES TO ADVECT MOISTURE FROM THE GULF OF MEXICO WITH A
COLD FRONT LOCATED ACROSS OKLAHOMA AND THE TEXAS PANHANDLE. A
1020MB HIGH IS LOCATED ACROSS THE ARKLAMISS.
FOR THE REST OF THE AFTERNOON AND INTO THIS EVENING...WILL CONTINUE
TO SEE CLOUDS BREAK UP AS MIXING AND DAYTIME HEATING CONTINUES.
THICKER STRATOCU RESIDES OVER ZAPATA/JIM HOGG/STARR COUNTIES AND MAY
BE A LITTLE HARDER TO BREAK UP CLOUDS IN THIS AREA. EVEN THOUGH
THICK CLOUDS ARE LOCATED HERE...TEMPERATURES HAVE WARMED NICELY AND
ARE ACTUALLY ABOVE FORECASTED HOURLY TEMPERATURES BUT LOOK GOOD FOR
THE HIGHS THIS AFTERNOON. WEAK IMPULSE TO OUR WEST IS FORECAST TO
SPARK CONVECTION ON THE SIERRA MADRE LATER THIS AFTERNOON AS IT
MOVES EAST. LATEST HRRR AND SPC 4KM WRF CONTINUE TO ROLL CONVECTION
OFF THE HIGHER TERRAIN AND MAKE A RUN AT OUR WESTERN ZONES. CURRENT
20 POPS OUT WEST LOOK GOOD FOR THIS EVENING AND MADE ONLY MINOR
ADJUSTMENTS TO MOVE JUST A LITTLE EASTWARD. ANY STORMS THAT DO CREEP
INTO OUR AREA WILL QUICKLY DISSIPATE TOWARDS MID EVENING AS BOUNDARY
LEVEL STABILIZES.
FOR TONIGHT...LOW CLOUDS WILL MOVE BACK IN ON SOUTHEASTERLY LOW
LEVEL WINDS BY MID TO LATE EVENING. NAM12/RAP/HRRR SHOW SIGNALS OF
SEA FOG DEVELOPING AND/OR ADVECTING IN TO THE COASTAL AREAS
OVERNIGHT. ADDED AREAS OF FOG ALONG THE COASTLINE WITH PATCHY FOG
INLAND. WILL HOLD OFF ON ANY DENSE FOG ADVISORY AT THIS TIME AND LET
SWING SHIFT MAKE THE CALL. INCREASED LOW TEMPERATURES SLIGHTLY WITH
EXPECTED ABUNDANCE OF LOW CLOUDS AND LOOKING AT MAINLY UPPER 60S TO
LOWER 70S.
FOR TUESDAY...WE WILL START OUT WITH THOSE LOW CLOUDS AND WILL BREAK
OUT AND DISSIPATE BY LATE MORNING. MIXING WILL TAKE PLACE BY MID
MORNING WITH GUSTY WINDS BY LATE MORNING. ANOTHER IMPULSE IS PROGGED
TO MOVE ACROSS THE AREA EARLY TUESDAY AFTERNOON. THERE IS PLACEMENT
ISSUES BETWEEN THE NAM AND GFS WITH THE NAM FURTHER NORTH AND THE
GFS IS ACROSS THE NORTHERN PORTION OF THE AREA AND IS WEAKER THAN
THE PREVIOUS RUN. KEPT POPS AS IS AND JUST TWEAKED LOCATION BASED ON
12Z GFS. A STRONG TO SEVERE STORM IS POSSIBLE GIVEN THE
THERMODYNAMIC ENVIRONMENT.
FOR TUESDAY NIGHT...THAT IMPULSE IS WELL NORTH OF THE AREA WITH JUST
A FEW SHOWERS LEFT OVER IN THE COASTAL WATERS. ATMOSPHERE WILL
STABILIZE RATHER RAPIDLY AFTER SUNSET WITH SKIES BECOMING CLOUDY
ONCE AGAIN. COLD FRONT WILL SAG INTO NORTH CENTRAL TEXAS WITH A SFC
LOW SOUTH OF THE TEXAS BIG BEND. CLOUDS WILL KEEP LOWS
UP...COMPARABLE TO TONIGHT.
LONG TERM /WEDNESDAY THROUGH MONDAY/...12Z MODEL RUN REMAINS
PERSISTENT ON THE TRACK AND STRENGTH OF THE MID TO UPPER LEVEL
TROUGH CURRENTLY OVER THE GREAT BASIN. BY 18Z WEDNESDAY GFS PLACES
THE UPPER TROUGH AXIS ACROSS NORTHWEST TEXAS AROUND 18Z WITH ITS
ASSOCIATED COLD FRONT APPROACHING THE NORTHERN PORTIONS OF THE
CWA. LARGE SCALE ASCENT COUPLED WITH LOW LEVEL CONVERGENCE ALONG
THE FRONT SHOULD BE THE COMBINATION NEEDED TO BRING ABOUT THE
CHANCE OF RAIN WE HAVE SEEN IN A WHILE. MODEST LOW LEVEL MOISTURE
WILL BE IN PLACE AND A LATE AFTERNOON FRONTAL PASSAGE SHOULD ALLOW
FOR SURFACE HEATING TO EXCEED GUIDANCE VALUES. SPC MAINTAINS
GENERAL THUNDERSTORM CHANCES FOR WEDNESDAY BUT CAN NOT RULE OUT
ISOLATED SEVERE STORMS AS THE ATMOSPHERE BECOMES INCREASINGLY
UNSTABLE. A DAY TO DAY ANALYSIS TO TAKE PLACE BEFORE WE ADD SEVERE
WORDING INTO THE FORECAST/GRIDS. POP GUIDANCE REMAINS AT LOW END
CHANCE BUT THIS MIGHT BE ON THE LOW END WITH DYNAMICS LOOKING A
BETTER THEN YESTERDAY AT THIS TIME. KEEP WED AND WEDNESDAY NIGHT
POPS CLOSE TO THE PREVIOUS FORECAST. AS MENTIONED TEMPERATURES
SHOULD CLIMB AHEAD OF THE COLD FRONT WITH A LATE AFTERNOON OR
EARLY EVENING PASSAGE. FORECAST HIGHS TO REMAIN ABOVE GUIDANCE
VALUES ESPECIALLY IF WE SEE MORE SUN PEAK THROUGH.
TROUGH AXIS AND SURFACE LOW PRESSURE QUICKLY EXITS TO THE EAST
THURSDAY MORNING. HUNG ON TO LOW POPS ACROSS THE COASTAL COUNTIES
BEFORE ENDING THURSDAY AFTERNOON AS THIS SYSTEM OPENS AND PUSHES
TO THE EAST. FAIR WEATHER ENSUES THURSDAY AFTERNOON INTO FRIDAY AS
SHORTWAVE RIDGING BUILDS OVERHEAD. COOL TO MILD TEMPERATURES
THURSDAY MORNING WITH SOME RECOVERY THURSDAY WITH HIGHS DROPPING
TO SLIGHTLY EARLY APRIL NORMALS.
GFS HAS BEEN INDICATING A QUICK RETURN OF GULF MOISTURE FRIDAY
NIGHT INTO SATURDAY. A WEAK DISTURBANCE IN THE ZONAL FLOW HAS BEEN
SEEN THE LAST FEW RUNS. ALTHOUGH GUIDANCE IS SHOWING VERY LOW POPS
ON SATURDAY WILL UP THE CHANCES SLIGHTLY TO MENTION ISOLATED
SHOWERS. MODEST DIVERGENCE AND SUFFICIENT MOISTURE...IF OCCURS
MIGHT BE ENOUGH FOR A FEW SHOWERS. WIND MACHINE TO POSSIBLY TURN
ON SUNDAY AND MONDAY AS NEXT TROUGH AND SURFACE LOW DEVELOP OUT
WEST. TEMPERATURES TO CLIMB AS USUAL.
MARINE /NOW THROUGH TUESDAY/GENERALLY FAVORABLE MARINE CONDITIONS
ARE EXPECTED THROUGH TUESDAY NIGHT WITH MODERATE EASTERLY TO
SOUTHEASTERLY WINDS. CONDITIONS MAY APPROACH EXERCISE CAUTION
LEVELS ON THE GULF OF MEXICO TONIGHT. SEAS SHOULD REMAIN LOW TO
MODERATE.
WEDNESDAY THROUGH SUNDAY...COLD FRONT ON TAP FOR A LATE WEDNESDAY OR
WEDNESDAY EVENING PASSAGE. LIGHT WINDS IN ADVANCE OF THE FRONT TO
SHIFT AND INCREASE FROM THE NORTH. SMALL CRAFT ADVISORIES STILL
EXPECTED WITH A 6 TO 12 HOUR WINDOW OF STRONG NORTH FLOW WEDNESDAY
NIGHT INTO EARLY THURSDAY AS SURFACE LOW PRESSURE DEVELOPS EAST OF
PADRE ISLAND ALONG THE FRONT. WITH THE SURFACE LOW TRACKING EAST
FAIRLY QUICKLY THURSDAY NORTH TO NORTHEAST WINDS TO WEAKEN. WINDS
VEER FRIDAY TO THE EAST AND SOUTHEAST BY FRIDAY NIGHT BUT THE
RETURN FLOW REMAINS LIGHT TO MODERATE. MORE SUBSTANTIAL INCREASE
OF SOUTHEAST WINDS RESUME SUNDAY INTO MONDAY AS THE GRADIENT
TIGHTENS WITH LOW PRESSURE DEEPENING ACROSS WESTERN TEXAS AND
NORTHEAST MEXICO.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
68/60
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1221 PM CDT TUE APR 2 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 307 AM CDT TUE APR 2 2013
LATEST WATER VAPOR IMAGERY AND 500 MB RAP ANALYSIS SHOWED NORTHWEST
FLOW ALOFT ACROSS THE UPPER MISSISSIPPI RIVER VALLEY EARLY THIS
MORNING. A SHORTWAVE TROUGH WAS NOTED OVER SOUTHERN MANITOBA
RACING SOUTHEAST TOWARD THE AREA. SURFACE OBSERVATIONS INDICATED
HIGH PRESSURE STRETCHING FROM THE EASTERN DAKOTAS SOUTHEAST INTO
THE MIDDLE MISSISSIPPI RIVER VALLEY. THE HIGH WILL SLIDE EAST INTO
THE AREA TODAY. MEANWHILE THE SHORTWAVE TROUGH WILL MOVE THROUGH
BUT WILL DO LITTLE MORE THAN PRODUCE AN INCREASE IN CLOUD OVER
NORTHERN AND CENTRAL WISCONSIN WITH THE REST OF THE FORECAST AREA
EXPERIENCING MOSTLY SUNNY SKIES. PLAN ON HIGHS TODAY RANGING FROM
THE LOWER 30S OVER NORTHERN WISCONSIN TO THE UPPER 30S TO AROUND
40 ACROSS NORTHEAST IOWA. THE HIGH IS EXPECTED TO SLIDE OVER THE
AREA TONIGHT PROVIDING QUIET WEATHER. ANOTHER UNSEASONABLY COLD
NIGHT IS IN STORE FOR THE FORECAST AREA WITH LOWS FALLING INTO THE
UPPER TEENS TO LOWER 20S. FAVORED COLD SPOTS OVER NORTH CENTRAL
WISCONSIN...SUCH AS DIAMOND LAKE...COULD SEE LOWS FALL INTO THE
SINGLE DIGITS ABOVE ZERO.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 307 AM CDT TUE APR 2 2013
HIGH PRESSURE WILL CONTINUE TO DOMINATE THE WEATHER ACROSS THE UPPER
MISSISSIPPI RIVER VALLEY ON WEDNESDAY WITH MOSTLY SUNNY SKIES
EXPECTED. THE SURFACE HIGH WILL SLIDE EAST LATE IN THE DAY AS A WEAK
COLD FRONT MOVES EAST OUT OF THE DAKOTAS. SOUTHERLY FLOW WILL
INCREASE ACROSS THE AREA AHEAD OF THIS FEATURE HELPING
TEMPERATURES WARM SLIGHTLY. PLAN ON HIGH TEMPERATURES RANGING FROM
THE LOWER 40S OVER NORTH CENTRAL WISCONSIN TO THE UPPER 40S TO
AROUND 50 ACROSS NORTHEAST IOWA. THE FRONT IS EXPECTED TO SAG
SOUTHEAST WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING AS A TROUGH
PUSHES EASTWARD ACROSS ONTARIO. FORECAST MODELS CONTINUE TO
GENERATE SOME LIGHT PRECIPITATION ALONG THE FRONT AS IT MOVES INTO
THE FORECAST AREA LATE WEDNESDAY NIGHT INTO THURSDAY MORNING.
FORCING IS NOT OVERLY IMPRESSIVE WITH THIS FEATURE WITH ONLY WEAK
ISENTROPIC LIFT NOTED. THE UPPER LEVEL FORCING IS PASSING WELL TO
THE NORTH OF THE REGION SO NOT EXPECTING MUCH PRECIPITATION.
HOWEVER...CANNOT RULE OUT SOME AREAS MEASURING SOME LIGHT RAIN MAINLY
ALONG AND NORTH OF INTESTATE 90. SOME SNOW COULD MIX IN EARLY IN
THE NORTH BEFORE TEMPERATURES WARM. HIGHS ON THURSDAY ARE EXPECTED
TO RANGE FROM LOWER TO MID 40S OVER NORTH CENTRAL WISCONSIN TO THE
LOWER 50S ACROSS NORTHEAST IOWA. THE FRONT WILL MOVE SOUTH AND
BECOME STATIONARY STRETCHING FROM THE WESTERN SOUTH DAKOTA EAST
THROUGH CENTRAL IOWA INTO NORTHERN ILLINOIS.
SURFACE HIGH PRESSURE IS EXPECTED TO RETURN BRIEFLY ON FRIDAY
PROVIDING ANOTHER QUIET DAY. MEANWHILE...A POTENT SHORTWAVE LOOKS TO
MOVE ACROSS THE PACIFIC NORTHWEST AND RACE EAST THROUGH THE DAKOTAS
LATE FRIDAY NIGHT. THE STATIONARY FRONT WILL LIFT NORTH AS THE WAVE
MOVES EAST AND ACT AS A BAROCLINIC ZONE. SURFACE LOW PRESSURE IS
EXPECTED TO DEVELOP ACROSS WESTERN SOUTH DAKOTA LATE FRIDAY
NIGHT...THEN MOVES EAST INTO THE UPPER MISSISSIPPI RIVER VALLEY
DURING THE DAY ON SATURDAY. STRONG 850 MB WARM AIR ADVECTION
DEVELOPS OVER THE AREA AHEAD OF THE APPROACHING LOW FRIDAY NIGHT
INTO SATURDAY MORNING. ISENTROPIC LIFT...ON THE 285-305K
SURFACES...INCREASES RAPIDLY AS THE LOW MOVES INTO THE AREA. THE
FORECAST MODELS HAVE BEEN SHOWING SOME DIFFERENCES REGARDING THE
PLACEMENT OF THE BOUNDARY WHICH WILL HAVE A HUGE IMPACT ON
PRECIPITATION TYPES. AT THIS TIME IT APPEARS THAT THE MAIN
PRECIPITATION TYPE WILL BE RAIN WITH PLENTY OF WARM AIR ADVECTING
NORTHWARD INTO THE REGION AHEAD OF THIS SYSTEM. THE PRECIPITATION
COULD START OUT AS SNOW EAST OF THE MISSISSIPPI RIVER LATE FRIDAY
NIGHT BUT SHOULD QUICKLY TRANSITION OVER TO ALL RAIN EARLY SATURDAY
MORNING. THE GEM AND GFS OFFER SIMILAR SOLUTIONS WITH THIS
SYSTEM...TAKING THE SURFACE LOW OVER SOUTHERN MINNESOTA ON SATURDAY
THEN ACROSS SOUTHERN WISCONSIN SATURDAY NIGHT. THE ECMWF OFFERS A
SLOWER AND MORE NORTHERLY SOLUTION...TAKING THE LOW OVER CENTRAL
MINNESOTA THROUGH NORTHERN WISCONSIN SATURDAY NIGHT. THE ECMWF
SOLUTION WOULD BRING MILD AIR INTO THE REGION ON SATURDAY...WITH
HIGHS CLIMBING INTO THE UPPER 50S TO LOWER 60S. ON THE OTHER HAND
THE GFS/GEM SOLUTION ARE ON THE COOLER SIDE WITH HIGHS RANGING
FROM THE UPPER 30S/LOWER 40S OVER NORTHERN WISCONSIN TO THE MID
50S ACROSS NORTHEAST IOWA. WILL LEAN TOWARDS A MODEL CONSENSUS
BLEND APPROACH. PLAN ON HIGHS RANGING FROM THE LOWER 40S OVER
NORTH CENTRAL WISCONSIN TO THE MID TO UPPER 50S SOUTH OF
INTERSTATE 90. THE LOW IS EXPECTED TO EXIT THE REGION ON SUNDAY.
AN ACTIVE PATTERN LOOKS TO DEVELOP MONDAY INTO TUESDAY AS A TROUGH
DIGS INTO THE SOUTHWEST CONUS. SOUTHWEST FLOW ALOFT COULD SET UP
OVER THE AREA. THE BAROCLINIC ZONE LOOKS TO REMAIN OVER THE UPPER
MIDWEST AS SHORTWAVE ENERGY EJECTS OUT OF OF THE SOUTHWEST FLOW
AND INTERACTS WITH IT. LATEST GUIDANCE SUGGESTS THE BOUNDARY WILL
STRETCH FROM NORTHERN OHIO WESTWARD THROUGH NORTHERN ILLINOIS
THROUGH SOUTHERN IOWA. WILL HAVE TO KEEP A CLOSE WATCH ON FUTURE
MODEL RUNS WITH THE POTENTIAL FOR THIS ACTIVE PATTERN TO BRING
SEVERAL ROUNDS OF PRECIPITATION TO THE REGION.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1221 PM CDT TUE APR 2 2013
QUIET STRETCH OF VFR WEATHER TO CONTINUE. HIGH PRESSURE CURRENTLY
EXTENDING FROM MANITOBA INTO MISSOURI AND ILLINOIS WILL MOVE
SOUTHEAST THROUGH THE PERIOD AND BE CENTERED NEAR THE SOUTHERN TIP
OF LAKE MICHIGAN BY LATE WEDNESDAY MORNING. THE NORTHWEST WINDS
WILL DROP OFF AROUND SUNSET TO 5 KNOTS OR LESS AND THEN COME
AROUND THE SOUTH AFTER SUNRISE WEDNESDAY ONCE THE RIDGE AXIS GOES
BY. OTHER THAN A FEW MID LEVEL CLOUDS THIS AFTERNOON...LITTLE OR
NO CLOUDS EXPECTED THROUGH THE PERIOD.
&&
.HYDROLOGY...
ISSUED AT 307 AM CDT TUE APR 2 2013
THE COMBINATION OF SNOW MELT AND THE RAIN OVER THE WEEKEND HAS
RESULTED IN FLOODING ALONG THE TREMPEALEAU RIVER AT DODGE. THE
LATEST STAGE WAS 9.21FT. FLOOD STAGE IS 9FT. THE RIVER IS
EXPECTED TO CREST THIS MORNING AND THEN SLOWLY FALL LATE THIS
AFTERNOON INTO THIS EVENING.
THE BLACK RIVER HAS CRESTED BELOW FLOOD STAGE AT BLACK RIVER
FALLS. WITH PLENTY OF SNOW UPSTREAM...THIS RIVER WILL LIKELY STAY
HIGH FOR THE NEXT SEVERAL DAYS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION...04
HYDROLOGY...WETENKAMP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
610 AM CDT TUE APR 2 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 307 AM CDT TUE APR 2 2013
LATEST WATER VAPOR IMAGERY AND 500 MB RAP ANALYSIS SHOWED NORTHWEST
FLOW ALOFT ACROSS THE UPPER MISSISSIPPI RIVER VALLEY EARLY THIS
MORNING. A SHORTWAVE TROUGH WAS NOTED OVER SOUTHERN MANITOBA
RACING SOUTHEAST TOWARD THE AREA. SURFACE OBSERVATIONS INDICATED
HIGH PRESSURE STRETCHING FROM THE EASTERN DAKOTAS SOUTHEAST INTO
THE MIDDLE MISSISSIPPI RIVER VALLEY. THE HIGH WILL SLIDE EAST INTO
THE AREA TODAY. MEANWHILE THE SHORTWAVE TROUGH WILL MOVE THROUGH
BUT WILL DO LITTLE MORE THAN PRODUCE AN INCREASE IN CLOUD OVER
NORTHERN AND CENTRAL WISCONSIN WITH THE REST OF THE FORECAST AREA
EXPERIENCING MOSTLY SUNNY SKIES. PLAN ON HIGHS TODAY RANGING FROM
THE LOWER 30S OVER NORTHERN WISCONSIN TO THE UPPER 30S TO AROUND
40 ACROSS NORTHEAST IOWA. THE HIGH IS EXPECTED TO SLIDE OVER THE
AREA TONIGHT PROVIDING QUIET WEATHER. ANOTHER UNSEASONABLY COLD
NIGHT IS IN STORE FOR THE FORECAST AREA WITH LOWS FALLING INTO THE
UPPER TEENS TO LOWER 20S. FAVORED COLD SPOTS OVER NORTH CENTRAL
WISCONSIN...SUCH AS DIAMOND LAKE...COULD SEE LOWS FALL INTO THE
SINGLE DIGITS ABOVE ZERO.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 307 AM CDT TUE APR 2 2013
HIGH PRESSURE WILL CONTINUE TO DOMINATE THE WEATHER ACROSS THE UPPER
MISSISSIPPI RIVER VALLEY ON WEDNESDAY WITH MOSTLY SUNNY SKIES
EXPECTED. THE SURFACE HIGH WILL SLIDE EAST LATE IN THE DAY AS A WEAK
COLD FRONT MOVES EAST OUT OF THE DAKOTAS. SOUTHERLY FLOW WILL
INCREASE ACROSS THE AREA AHEAD OF THIS FEATURE HELPING
TEMPERATURES WARM SLIGHTLY. PLAN ON HIGH TEMPERATURES RANGING FROM
THE LOWER 40S OVER NORTH CENTRAL WISCONSIN TO THE UPPER 40S TO
AROUND 50 ACROSS NORTHEAST IOWA. THE FRONT IS EXPECTED TO SAG
SOUTHEAST WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING AS A TROUGH
PUSHES EASTWARD ACROSS ONTARIO. FORECAST MODELS CONTINUE TO
GENERATE SOME LIGHT PRECIPITATION ALONG THE FRONT AS IT MOVES INTO
THE FORECAST AREA LATE WEDNESDAY NIGHT INTO THURSDAY MORNING.
FORCING IS NOT OVERLY IMPRESSIVE WITH THIS FEATURE WITH ONLY WEAK
ISENTROPIC LIFT NOTED. THE UPPER LEVEL FORCING IS PASSING WELL TO
THE NORTH OF THE REGION SO NOT EXPECTING MUCH PRECIPITATION.
HOWEVER...CANNOT RULE OUT SOME AREAS MEASURING SOME LIGHT RAIN MAINLY
ALONG AND NORTH OF INTESTATE 90. SOME SNOW COULD MIX IN EARLY IN
THE NORTH BEFORE TEMPERATURES WARM. HIGHS ON THURSDAY ARE EXPECTED
TO RANGE FROM LOWER TO MID 40S OVER NORTH CENTRAL WISCONSIN TO THE
LOWER 50S ACROSS NORTHEAST IOWA. THE FRONT WILL MOVE SOUTH AND
BECOME STATIONARY STRETCHING FROM THE WESTERN SOUTH DAKOTA EAST
THROUGH CENTRAL IOWA INTO NORTHERN ILLINOIS.
SURFACE HIGH PRESSURE IS EXPECTED TO RETURN BRIEFLY ON FRIDAY
PROVIDING ANOTHER QUIET DAY. MEANWHILE...A POTENT SHORTWAVE LOOKS TO
MOVE ACROSS THE PACIFIC NORTHWEST AND RACE EAST THROUGH THE DAKOTAS
LATE FRIDAY NIGHT. THE STATIONARY FRONT WILL LIFT NORTH AS THE WAVE
MOVES EAST AND ACT AS A BAROCLINIC ZONE. SURFACE LOW PRESSURE IS
EXPECTED TO DEVELOP ACROSS WESTERN SOUTH DAKOTA LATE FRIDAY
NIGHT...THEN MOVES EAST INTO THE UPPER MISSISSIPPI RIVER VALLEY
DURING THE DAY ON SATURDAY. STRONG 850 MB WARM AIR ADVECTION
DEVELOPS OVER THE AREA AHEAD OF THE APPROACHING LOW FRIDAY NIGHT
INTO SATURDAY MORNING. ISENTROPIC LIFT...ON THE 285-305K
SURFACES...INCREASES RAPIDLY AS THE LOW MOVES INTO THE AREA. THE
FORECAST MODELS HAVE BEEN SHOWING SOME DIFFERENCES REGARDING THE
PLACEMENT OF THE BOUNDARY WHICH WILL HAVE A HUGE IMPACT ON
PRECIPITATION TYPES. AT THIS TIME IT APPEARS THAT THE MAIN
PRECIPITATION TYPE WILL BE RAIN WITH PLENTY OF WARM AIR ADVECTING
NORTHWARD INTO THE REGION AHEAD OF THIS SYSTEM. THE PRECIPITATION
COULD START OUT AS SNOW EAST OF THE MISSISSIPPI RIVER LATE FRIDAY
NIGHT BUT SHOULD QUICKLY TRANSITION OVER TO ALL RAIN EARLY SATURDAY
MORNING. THE GEM AND GFS OFFER SIMILAR SOLUTIONS WITH THIS
SYSTEM...TAKING THE SURFACE LOW OVER SOUTHERN MINNESOTA ON SATURDAY
THEN ACROSS SOUTHERN WISCONSIN SATURDAY NIGHT. THE ECMWF OFFERS A
SLOWER AND MORE NORTHERLY SOLUTION...TAKING THE LOW OVER CENTRAL
MINNESOTA THROUGH NORTHERN WISCONSIN SATURDAY NIGHT. THE ECMWF
SOLUTION WOULD BRING MILD AIR INTO THE REGION ON SATURDAY...WITH
HIGHS CLIMBING INTO THE UPPER 50S TO LOWER 60S. ON THE OTHER HAND
THE GFS/GEM SOLUTION ARE ON THE COOLER SIDE WITH HIGHS RANGING
FROM THE UPPER 30S/LOWER 40S OVER NORTHERN WISCONSIN TO THE MID
50S ACROSS NORTHEAST IOWA. WILL LEAN TOWARDS A MODEL CONSENSUS
BLEND APPROACH. PLAN ON HIGHS RANGING FROM THE LOWER 40S OVER
NORTH CENTRAL WISCONSIN TO THE MID TO UPPER 50S SOUTH OF
INTERSTATE 90. THE LOW IS EXPECTED TO EXIT THE REGION ON SUNDAY.
AN ACTIVE PATTERN LOOKS TO DEVELOP MONDAY INTO TUESDAY AS A TROUGH
DIGS INTO THE SOUTHWEST CONUS. SOUTHWEST FLOW ALOFT COULD SET UP
OVER THE AREA. THE BAROCLINIC ZONE LOOKS TO REMAIN OVER THE UPPER
MIDWEST AS SHORTWAVE ENERGY EJECTS OUT OF OF THE SOUTHWEST FLOW
AND INTERACTS WITH IT. LATEST GUIDANCE SUGGESTS THE BOUNDARY WILL
STRETCH FROM NORTHERN OHIO WESTWARD THROUGH NORTHERN ILLINOIS
THROUGH SOUTHERN IOWA. WILL HAVE TO KEEP A CLOSE WATCH ON FUTURE
MODEL RUNS WITH THE POTENTIAL FOR THIS ACTIVE PATTERN TO BRING
SEVERAL ROUNDS OF PRECIPITATION TO THE REGION.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 610 AM CDT TUE APR 2 2013
SKIES SHOULD REMAIN CLEAR FOR MOST OF THE NEXT 24 HOURS WITH A
BRIEF PERIOD OF SCATTERED MID TO UPPER LEVEL CLOUDS MOVING THROUGH
IN THE LATE MORNING/EARLY AFTERNOON. OTHERWISE...NORTHWEST WINDS
WILL PEAK AROUND 10KTS LATER THIS MORNING/EARLY AFTERNOON BEFORE
GOING LIGHT AND VARIABLE TONIGHT AS A RIDGE OF HIGH PRESSURE MOVES
IN ACROSS THE AREA.
&&
.HYDROLOGY...
ISSUED AT 307 AM CDT TUE APR 2 2013
THE COMBINATION OF SNOW MELT AND THE RAIN OVER THE WEEKEND HAS
RESULTED IN FLOODING ALONG THE TREMPEALEAU RIVER AT DODGE. THE
LATEST STAGE WAS 9.21FT. FLOOD STAGE IS 9FT. THE RIVER IS
EXPECTED TO CREST THIS MORNING AND THEN SLOWLY FALL LATE THIS
AFTERNOON INTO THIS EVENING.
THE BLACK RIVER HAS CRESTED BELOW FLOOD STAGE AT BLACK RIVER
FALLS. WITH PLENTY OF SNOW UPSTREAM...THIS RIVER WILL LIKELY STAY
HIGH FOR THE NEXT SEVERAL DAYS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION...HALBACH
HYDROLOGY...WETENKAMP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
307 AM CDT TUE APR 2 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 307 AM CDT TUE APR 2 2013
LATEST WATER VAPOR IMAGERY AND 500 MB RAP ANALYSIS SHOWED NORTHWEST
FLOW ALOFT ACROSS THE UPPER MISSISSIPPI RIVER VALLEY EARLY THIS
MORNING. A SHORTWAVE TROUGH WAS NOTED OVER SOUTHERN MANITOBA
RACING SOUTHEAST TOWARD THE AREA. SURFACE OBSERVATIONS INDICATED
HIGH PRESSURE STRETCHING FROM THE EASTERN DAKOTAS SOUTHEAST INTO
THE MIDDLE MISSISSIPPI RIVER VALLEY. THE HIGH WILL SLIDE EAST INTO
THE AREA TODAY. MEANWHILE THE SHORTWAVE TROUGH WILL MOVE THROUGH
BUT WILL DO LITTLE MORE THAN PRODUCE AN INCREASE IN CLOUD OVER
NORTHERN AND CENTRAL WISCONSIN WITH THE REST OF THE FORECAST AREA
EXPERIENCING MOSTLY SUNNY SKIES. PLAN ON HIGHS TODAY RANGING FROM
THE LOWER 30S OVER NORTHERN WISCONSIN TO THE UPPER 30S TO AROUND
40 ACROSS NORTHEAST IOWA. THE HIGH IS EXPECTED TO SLIDE OVER THE
AREA TONIGHT PROVIDING QUIET WEATHER. ANOTHER UNSEASONABLY COLD
NIGHT IS IN STORE FOR THE FORECAST AREA WITH LOWS FALLING INTO THE
UPPER TEENS TO LOWER 20S. FAVORED COLD SPOTS OVER NORTH CENTRAL
WISCONSIN...SUCH AS DIAMOND LAKE...COULD SEE LOWS FALL INTO THE
SINGLE DIGITS ABOVE ZERO.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 307 AM CDT TUE APR 2 2013
HIGH PRESSURE WILL CONTINUE TO DOMINATE THE WEATHER ACROSS THE UPPER
MISSISSIPPI RIVER VALLEY ON WEDNESDAY WITH MOSTLY SUNNY SKIES
EXPECTED. THE SURFACE HIGH WILL SLIDE EAST LATE IN THE DAY AS A WEAK
COLD FRONT MOVES EAST OUT OF THE DAKOTAS. SOUTHERLY FLOW WILL
INCREASE ACROSS THE AREA AHEAD OF THIS FEATURE HELPING
TEMPERATURES WARM SLIGHTLY. PLAN ON HIGH TEMPERATURES RANGING FROM
THE LOWER 40S OVER NORTHCENTRAL WISCONSIN TO THE UPPER 40S TO
AROUND 50 ACROSS NORTHEAST IOWA. THE FRONT IS EXPECTED TO SAG
SOUTHEAST WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING AS A TROUGH
PUSHES EASTWARD ACROSS ONTARIO. FORECAST MODELS CONTINUE TO
GENERATE SOME LIGHT PRECIPITATION ALONG THE FRONT AS IT MOVES INTO
THE FORECAST AREA LATE WEDNESDAY NIGHT INTO THURSDAY MORNING.
FORCING IS NOT OVERLY IMPRESSIVE WITH THIS FEATURE WITH ONLY WEAK
ISENTROPIC LIFT NOTED. THE UPPER LEVEL FORCING IS PASSING WELL TO
THE NORTH OF THE REGION SO NOT EXPECTING MUCH PRECIPITATION.
HOWEVER...CANNOT RULE OUT SOME AREAS MEASURING SOME LIGHT RAIN MAINLY
ALONG AND NORTH OF INTESTATE 90. SOME SNOW COULD MIX IN EARLY IN
THE NORTH BEFORE TEMPERATURES WARM. HIGHS ON THURSDAY ARE EXPECTED
TO RANGE FROM LOWER TO MID 40S OVER NORTHCENTRAL WISCONSIN TO THE
LOWER 50S ACROSS NORTHEAST IOWA. THE FRONT WILL MOVE SOUTH AND
BECOME STATIONARY STRETCHING FROM THE WESTERN SOUTH DAKOTA EAST
THROUGH CENTRAL IOWA INTO NORTHERN ILLINOIS.
SURFACE HIGH PRESSURE IS EXPECTED TO RETURN BRIEFLY ON FRIDAY
PROVIDING ANOTHER QUIET DAY. MEANWHILE...A POTENT SHORTWAVE LOOKS TO
MOVE ACROSS THE PACIFIC NORTHWEST AND RACE EAST THROUGH THE DAKOTAS
LATE FRIDAY NIGHT. THE STATIONARY FRONT WILL LIFT NORTH AS THE WAVE
MOVES EAST AND ACT AS A BAROCLINIC ZONE. SURFACE LOW PRESSURE IS
EXPECTED TO DEVELOP ACROSS WESTERN SOUTH DAKOTA LATE FRIDAY
NIGHT...THEN MOVES EAST INTO THE UPPER MISSISSIPPI RIVER VALLEY
DURING THE DAY ON SATURDAY. STRONG 850 MB WARM AIR ADVECTION
DEVELOPS OVER THE AREA AHEAD OF THE APPROACHING LOW FRIDAY NIGHT
INTO SATURDAY MORNING. ISENTROPIC LIFT...ON THE 285-305K
SURFACES...INCREASES RAPIDLY AS THE LOW MOVES INTO THE AREA. THE
FORECAST MODELS HAVE BEEN SHOWING SOME DIFFERENCES REGARDING THE
PLACEMENT OF THE BOUNDARY WHICH WILL HAVE A HUGE IMPACT ON
PRECIPITATION TYPES. AT THIS TIME IT APPEARS THAT THE MAIN
PRECIPITATION TYPE WILL BE RAIN WITH PLENTY OF WARM AIR ADVECTING
NORTHWARD INTO THE REGION AHEAD OF THIS SYSTEM. THE PRECIPITATION
COULD START OUT AS SNOW EAST OF THE MISSISSIPPI RIVER LATE FRIDAY
NIGHT BUT SHOULD QUICKLY TRANSITION OVER TO ALL RAIN EARLY SATURDAY
MORNING. THE GEM AND GFS OFFER SIMILAR SOLUTIONS WITH THIS
SYSTEM...TAKING THE SURFACE LOW OVER SOUTHERN MINNESOTA ON SATURDAY
THEN ACROSS SOUTHERN WISCONSIN SATURDAY NIGHT. THE ECMWF OFFERS A
SLOWER AND MORE NORTHERLY SOLUTION...TAKING THE LOW OVER CENTRAL
MINNESOTA THROUGH NORTHERN WISCONSIN SATURDAY NIGHT. THE ECMWF
SOLUTION WOULD BRING MILD AIR INTO THE REGION ON SATURDAY...WITH
HIGHS CLIMBING INTO THE UPPER 50S TO LOWER 60S. ON THE OTHER HAND
THE GFS/GEM SOLUTION ARE ON THE COOLER SIDE WITH HIGHS RANGING
FROM THE UPPER 30S/LOWER 40S OVER NORTHERN WISCONSIN TO THE MID
50S ACROSS NORTHEAST IOWA. WILL LEAN TOWARDS A MODEL CONSENSUS
BLEND APPROACH. PLAN ON HIGHS RANGING FROM THE LOWER 40S OVER
NORTH CENTRAL WISCONSIN TO THE MID TO UPPER 50S SOUTH OF
INTERSTATE 90. THE LOW IS EXPECTED TO EXIT THE REGION ON SUNDAY.
AN ACTIVE PATTERN LOOKS TO DEVELOP MONDAY INTO TUESDAY AS A TROUGH
DIGS INTO THE SOUTHWEST CONUS. SOUTHWEST FLOW ALOFT COULD SET UP
OVER THE AREA. THE BAROCLINIC ZONE LOOKS TO REMAIN OVER THE UPPER
MIDWEST AS SHORTWAVE ENERGY EJECTS OUT OF OF THE SOUTHWEST FLOW
AND INTERACTS WITH IT. LATEST GUIDANCE SUGGESTS THE BOUNDARY WILL
STRETCH FROM NORTHERN OHIO WESTWARD THROUGH NORTHERN ILLINOIS
THROUGH SOUTHERN IOWA. WILL HAVE TO KEEP A CLOSE WATCH ON FUTURE
MODEL RUNS WITH THE POTENTIAL FOR THIS ACTIVE PATTERN TO BRING
SEVERAL ROUNDS OF PRECIPITATION TO THE REGION.
&&
.AVIATION...TONIGHT AND TUESDAY
631 PM CDT MON APR 1 2013
VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD WITH SURFACE HIGH
BEING THE DOMINATE WEATHER FEATURE. A WEAK SHORTWAVE TROUGH WILL
DROP ACROSS THE AREA TUESDAY WHICH WILL ONLY PRODUCE SOME
SCATTERED MID LEVEL CLOUDS. NORTHWEST WINDS WILL CONTINUE AT 5 TO
10 KNOTS TONIGHT AND AROUND 12 KNOTS TUESDAY AFTERNOON.
&&
.HYDROLOGY...
ISSUED AT 307 AM CDT TUE APR 2 2013
THE COMBINATION OF SNOW MELT AND THE RAIN OVER THE WEEKEND HAS
RESULTED IN FLOODING ALONG THE TREMPEALEAU RIVER AT DODGE. THE
LATEST STAGE WAS 9.21FT. FLOOD STAGE IS 9FT. THE RIVER IS
EXPECTED TO CREST THIS MORNING AND THEN SLOWLY FALL LATE THIS
AFTERNOON INTO THIS EVENING.
THE BLACK RIVER HAS CRESTED BELOW FLOOD STAGE AT BLACK RIVER
FALLS. WITH PLENTY OF SNOW UPSTREAM...THIS RIVER WILL LIKELY STAY
HIGH FOR THE NEXT SEVERAL DAYS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION...RABERDING
HYDROLOGY...WETENKAMP
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
610 AM MDT TUE APR 2 2013
.SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT)
ISSUED AT 345 AM MDT TUE APR 2 2013
AREA OF LOW PRESSURE DETACHED FROM THE MEAN FLOW WILL SLOWLY MOVE
OUT OF UTAH THIS MORNING AND INTO THE SOUTHERN PLAINS BY WEDNESDAY
NIGHT. THE FEW WEAK SHOWERS THAT HAVE PUSHED NORTHEAST ACROSS THE
CO/WY STATELINE HAVE DISSIPATED QUICKLY LOSING BEST QG VERTICAL
VELOCITIES WHICH ARE WELL SOUTH OF THE CWFA. ALTHOUGH STILL CANT
RULE OUT ISOLATED TO LOCALLY SCATTERED SHOWERS/DRIZZLE THROUGH THE
AFTERNOON...THESE WILL NEED TO RELY MAINLY ON LFQ H3 JET HELP AND
INSTABILITY. AS A RESULT...HAVE DECREASED PRECIPITATION CHANCES SOME
ESPECIALLY THIS MORNING...KEEPING THE HIGHEST IN AREAS NR THE CO/WY
STATELINE AND ALONG THE I80 CORRIDOR. ADDITIONALLY...PROGD LIFTED
INDICES WILL FALL SLIGHTLY NEGATIVE FOR AREAS WEST OF THE LARAMIE
RANGE THIS AFTERNOON. SO KEPT THE MENTION OF THUNDER FOR THESE
AREAS. ALTHOUGH WOULD EXPECT THE BEST THUNDER POTENTIAL TO BE OVER
THE SNOWY/SIERRA MADRE RANGES. THE OTHER CONCERN THIS MORNING IS
PATCHY FOG THAT HAS DEVELOPED ALONG THE INTERSTATE 80 SUMMIT. THE
AFFECTED AREA HAS THUS FAR BEEN CONFINED TO A FEW MILE STRETCH OF
I80. LATEST HRRR EVEN SHOWS SOME OF THIS STRATUS DESCENDING ALONG
THE EASTERN FOOTHILLS OF THE SOUTHERN LARAMIE RANGE TOWARDS DAYBREAK
AS WELL. FOR NOW...HAVE ADDED FOG MENTION TO THIS AREA THROUGH
MID-MORNING. H7 TEMPERATURES HOVERING AROUND -3C COMBINED WITH
THICKER CLOUD-COVER WILL TEMPER AFTERNOON HIGH TEMPERATURES
SOMEWHAT...WITH MAINLY 50S EXPECTED. THE EXCEPTION WILL BE AREAS IN
AND AROUND THE SOUTHEAST WYOMING MOUNTAINS WHERE HIGHS WILL ONLY
REACH THE 40S.
LATEST MODEL GUIDANCE HINTS AT THE POSSIBILITY OF PATCHY FOG FROM
CHEYENNE TO SIDNEY AGAIN LATER TONIGHT AND EARLY WEDNESDAY. SO HAVE
ADDED PATCHY MENTION. EXPECT MAINLY DRY CONDITIONS TONIGHT AS BEST
MOISTURE/LIFT ASSOCIATED WITH THE UPPER LOW EXITS TO THE SOUTHEAST
OF THE AREA.
HEIGHTS WILL RISE BEHIND THE DEPARTING LOW PRESSURE SYSTEM ON
WEDNESDAY. EXPECT A MOSTLY DRY DAY AS THIS WEAK TRANSITORY RIDGE
TRANSITIONS TO NORTHWEST FLOW. H7 TEMPERATURES WILL CLIMB TO
FREEZING AND WITH LESS CLOUD-COVER WILL SEE HIGHS CLIMB WELL INTO
THE 50S AND 60S AT ALL LOWER ELEVATIONS. MAY EVEN FLIRT WITH 70
NORTH OF THE PINE RIDGE. MODELS POINT TO ANOTHER WEAK FRONT WILL
PUSH SOUTH THROUGH THE AREA WEDNESDAY NIGHT. MOISTURE LOOKS TO BE
LIMITING FACTOR...SO KEPT WEDNESDAY NIGHT DRY FOR NOW.
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 345 AM MDT TUE APR 2 2013
UPPER RIDGE WILL SHIFT EAST ACROSS THE CWA THURSDAY AND THURSDAY
NIGHT RESULTING IN MILD AND DRY WEATHER THROUGH MOST OF FRIDAY.
NEXT UPPER TROUGH TO AFFECT THE REGION WILL APPROACH ON FRIDAY AND
MAY SPREAD SOME SHOWERS INTO FAR WESTERN AND NORTHERN PARTS OF THE
CWA LATE IN THE DAY. THIS SYSTEM WILL PASS ACROSS FRIDAY NIGHT
BRINGING A MODEST PACIFIC FRONT AND A LITTLE COOLER TEMPERATURES
FOR SATURDAY. YET ANOTHER SHORTWAVE SHOULD PASS BY SATURDAY NIGHT
BEFORE A MORE SIGNIFICANT TROUGH DIGS OVER THE WESTERN CONUS
SUNDAY NIGHT AND MONDAY SPREADING MORE WIDESPREAD RAIN AND SNOW
SHOWERS ACROSS THE CWA AT THAT TIME. TEMPERATURES WILL ALSO COOL
SUNDAY THROUGH MONDAY DUE TO MORE CLOUD COVER AND LOWERING
HEIGHTS. MODELS SHOW THIS SYSTEM COULD BE A DECENT PRECIPITATION
PRODUCER FOR THE CWA EARLY NEXT WEEK BUT WILL SEE HOW FUTURE RUNS
TURN OUT BEFORE GETTING TOO EXCITED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 610 AM MDT TUE APR 2 2013
SLOW MOVING AREA OF LOW PRESSURE WILL MOVE FROM UTAH INTO
COLORADO TODAY. A FEW SHOWERS ALONG WITH MVFR/IFR CIGS WILL
DEVELOP AND LIFT NORTHEAST AFFECTING MAINLY SOUTHEAST WYOMING
TERMINALS TODAY. HAVE INCLUDED A TEMPO GROUP THROUGH 14Z/15Z AT
KLAR AND KCYS AS A BAND OF WEAK SHOWERS HAVE DEVELOPED TO THEIR
NORTH. OTHERWISE...EXPECT VFR CONDITIONS TO PREVAIL AT AREA
AIRPORTS. FOG POTENTIAL WILL RETURN AFTER 06Z TONIGHT FROM KCYS TO
KSNY...SO HAVE INCLUDED A VCFG MENTION FOR NOW.
&&
.FIRE WEATHER...
ISSUED AT 345 AM MDT TUE APR 2 2013
MINIMAL FIRE WEATHER CONCERNS EXPECTED THIS WEEK. AN AREA OF LOW
PRESSURE WILL MOVING FROM UTAH INTO COLORADO TODAY. CLOUDS AND LIGHT
PRECIPITATION CHANCES WILL HOLD HIGH TEMPERATURES DOWN AND MINIMUM
RELATIVE HUMIDITIES UP TODAY. THERE WILL BE UP TO A FEW INCHES OF
NEW SNOW OVER THE SNOWY AND SIERRA MADRES THROUGH TODAY.
PRECIPITATION WILL DECREASE TONIGHT...WITH DRIER CONDITIONS SETTLING
IN FOR WEDNESDAY THROUGH FRIDAY. WARMER TEMPERATURES ARE EXPECTED AS
WELL...WITH 70S RETURNING TO EASTERN PORTIONS OF THE DISTRICT BY
WEEKS END. MINIMUM RELATIVE HUMIDITIES WILL HOVER IN THE 20 TO 30
PERCENT RANGE EACH DAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...HAHN
LONG TERM...RE
AVIATION...HAHN
FIRE WEATHER...HAHN
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
345 AM MDT TUE APR 2 2013
.SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT)
ISSUED AT 345 AM MDT TUE APR 2 2013
AREA OF LOW PRESSURE DETACHED FROM THE MEAN FLOW WILL SLOWLY MOVE
OUT OF UTAH THIS MORNING AND INTO THE SOUTHERN PLAINS BY WEDNESDAY
NIGHT. THE FEW WEAK SHOWERS THAT HAVE PUSHED NORTHEAST ACROSS THE
CO/WY STATELINE HAVE DISSIPATED QUICKLY LOSING BEST QG VERTICAL
VELOCITIES WHICH ARE WELL SOUTH OF THE CWFA. ALTHOUGH STILL CANT
RULE OUT ISOLATED TO LOCALLY SCATTERED SHOWERS/DRIZZLE THROUGH THE
AFTERNOON...THESE WILL NEED TO RELY MAINLY ON LFQ H3 JET HELP AND
INSTABILITY. AS A RESULT...HAVE DECREASED PRECIPITATION CHANCES SOME
ESPECIALLY THIS MORNING...KEEPING THE HIGHEST IN AREAS NR THE CO/WY
STATELINE AND ALONG THE I80 CORRIDOR. ADDITIONALLY...PROGD LIFTED
INDICES WILL FALL SLIGHTLY NEGATIVE FOR AREAS WEST OF THE LARAMIE
RANGE THIS AFTERNOON. SO KEPT THE MENTION OF THUNDER FOR THESE
AREAS. ALTHOUGH WOULD EXPECT THE BEST THUNDER POTENTIAL TO BE OVER
THE SNOWY/SIERRA MADRE RANGES. THE OTHER CONCERN THIS MORNING IS
PATCHY FOG THAT HAS DEVELOPED ALONG THE INTERSTATE 80 SUMMIT. THE
AFFECTED AREA HAS THUS FAR BEEN CONFINED TO A FEW MILE STRETCH OF
I80. LATEST HRRR EVEN SHOWS SOME OF THIS STRATUS DESCENDING ALONG
THE EASTERN FOOTHILLS OF THE SOUTHERN LARAMIE RANGE TOWARDS DAYBREAK
AS WELL. FOR NOW...HAVE ADDED FOG MENTION TO THIS AREA THROUGH
MID-MORNING. H7 TEMPERATURES HOVERING AROUND -3C COMBINED WITH
THICKER CLOUD-COVER WILL TEMPER AFTERNOON HIGH TEMPERATURES
SOMEWHAT...WITH MAINLY 50S EXPECTED. THE EXCEPTION WILL BE AREAS IN
AND AROUND THE SOUTHEAST WYOMING MOUNTAINS WHERE HIGHS WILL ONLY
REACH THE 40S.
LATEST MODEL GUIDANCE HINTS AT THE POSSIBILITY OF PATCHY FOG FROM
CHEYENNE TO SIDNEY AGAIN LATER TONIGHT AND EARLY WEDNESDAY. SO HAVE
ADDED PATCHY MENTION. EXPECT MAINLY DRY CONDITIONS TONIGHT AS BEST
MOISTURE/LIFT ASSOCIATED WITH THE UPPER LOW EXITS TO THE SOUTHEAST
OF THE AREA.
HEIGHTS WILL RISE BEHIND THE DEPARTING LOW PRESSURE SYSTEM ON
WEDNESDAY. EXPECT A MOSTLY DRY DAY AS THIS WEAK TRANSITORY RIDGE
TRANSITIONS TO NORTHWEST FLOW. H7 TEMPERATURES WILL CLIMB TO
FREEZING AND WITH LESS CLOUD-COVER WILL SEE HIGHS CLIMB WELL INTO
THE 50S AND 60S AT ALL LOWER ELEVATIONS. MAY EVEN FLIRT WITH 70
NORTH OF THE PINE RIDGE. MODELS POINT TO ANOTHER WEAK FRONT WILL
PUSH SOUTH THROUGH THE AREA WEDNESDAY NIGHT. MOISTURE LOOKS TO BE
LIMITING FACTOR...SO KEPT WEDNESDAY NIGHT DRY FOR NOW.
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 345 AM MDT TUE APR 2 2013
UPPER RIDGE WILL SHIFT EAST ACROSS THE CWA THURSDAY AND THURSDAY
NIGHT RESULTING IN MILD AND DRY WEATHER THROUGH MOST OF FRIDAY.
NEXT UPPER TROUGH TO AFFECT THE REGION WILL APPROACH ON FRIDAY AND
MAY SPREAD SOME SHOWERS INTO FAR WESTERN AND NORTHERN PARTS OF THE
CWA LATE IN THE DAY. THIS SYSTEM WILL PASS ACROSS FRIDAY NIGHT
BRINGING A MODEST PACIFIC FRONT AND A LITTLE COOLER TEMPERATURES
FOR SATURDAY. YET ANOTHER SHORTWAVE SHOULD PASS BY SATURDAY NIGHT
BEFORE A MORE SIGNIFICANT TROUGH DIGS OVER THE WESTERN CONUS
SUNDAY NIGHT AND MONDAY SPREADING MORE WIDESPREAD RAIN AND SNOW
SHOWERS ACROSS THE CWA AT THAT TIME. TEMPERATURES WILL ALSO COOL
SUNDAY THROUGH MONDAY DUE TO MORE CLOUD COVER AND LOWERING
HEIGHTS. MODELS SHOW THIS SYSTEM COULD BE A DECENT PRECIPITATION
PRODUCER FOR THE CWA EARLY NEXT WEEK BUT WILL SEE HOW FUTURE RUNS
TURN OUT BEFORE GETTING TOO EXCITED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1209 AM MDT TUE APR 2 2013
AN AREA OF LOW PRESSURE SPINNING THROUGH UTAH EARLY THIS MORNING
WILL VERY SLOWLY PUSH INTO COLORADO BY LATE TODAY. AS A RESULT...ITS
IMPACT WILL BE CONFINED TO SE WYOMING TERMINALS IN THE WAY OF
MVFR/IFR CIGS/VSBYS THROUGH AROUND 18Z TUESDAY. WILL SEE PERIODIC
BANDS OF WEAK SHOWERS LIFTING NORTHEAST AND HAVE INCLUDED MENTION
PRIMARILY AT KCYS DURING THE MORNING HOURS. CONFIDENCE IS LESS AT
KRWL AND KLAR...THUS HAVE LEFT VCSH IN UNTIL TIMING CAN BE NARROWED.
CONDITIONS WILL IMPROVE ACROSS SE WYOMING BY THIS AFTERNOON.
OTHERWISE...EXPECT VFR CONDITIONS AT WESTERN NEBRASKA PANHANDLE
AIRFIELDS THROUGH THE FORECAST PERIOD.
&&
.FIRE WEATHER...
ISSUED AT 345 AM MDT TUE APR 2 2013
MINIMAL FIRE WEATHER CONCERNS EXPECTED THIS WEEK. AN AREA OF LOW
PRESSURE WILL MOVING FROM UTAH INTO COLORADO TODAY. CLOUDS AND LIGHT
PRECIPITATION CHANCES WILL HOLD HIGH TEMPERATURES DOWN AND MINIMUM
RELATIVE HUMIDITIES UP TODAY. THERE WILL BE UP TO A FEW INCHES OF
NEW SNOW OVER THE SNOWY AND SIERRA MADRES THROUGH TODAY.
PRECIPITATION WILL DECREASE TONIGHT...WITH DRIER CONDITIONS SETTLING
IN FOR WEDNESDAY THROUGH FRIDAY. WARMER TEMPERATURES ARE EXPECTED AS
WELL...WITH 70S RETURNING TO EASTERN PORTIONS OF THE DISTRICT BY
WEEKS END. MINIMUM RELATIVE HUMIDITIES WILL HOVER IN THE 20 TO 30
PERCENT RANGE EACH DAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...HAHN
LONG TERM...RE
AVIATION...HAHN
FIRE WEATHER...HAHN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1058 PM MDT WED APR 3 2013
.UPDATE...
ISSUED AT 905 PM MDT WED APR 3 2013
CURRENT WATER VAPOR IMAGERY INDICATING AN EMBEDDED SHORT WAVE
TRANSLATING ACROSS SOUTH CENTRAL WYOMING AND INTO NORTH CENTRAL
COLORADO AT THIS TIME. REGIONAL RADARS INDICATING SHOWERS ALONG
WITH A FEW LIGHTNING STRIKES ASSOCIATED WITH THIS SYSTEM MOVING
ACROSS NORTHERN COLORADO AT THIS TIME. LATEST NAM AND RAP HAVE
SHOWERS DIMINISHING AS THEY CONTINUE TO MOVE SOUTH AND EAST WITH
ONLY INCREASING MID AND AND HIGH LEVEL CLOUDS ACROSS SOUTH CENTRAL
AND SOUTHEAST COLORADO. HOWEVER...THE LAST FEW RUNS OF THE HRRR
IS INDICATING A FEW SHOWERS MOVING OUT ACROSS THE FRONT RANGE AND
INTO NORTHERN AND EASTERN PORTIONS OF EL PASO COUNTY AFTER
MIDNIGHT. HAVE NOT BOUGHT OFF ON THIS SCENARIO WITH SHOWERS
SEEMINGLY DIMINISHING WITH THE LOSS OF HEATING...THOUGH WILL NEED
TO MONITOR LATEST HRRR TRENDS.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 313 PM MDT WED APR 3 2013
CURRENTLY...
SKIES CLEARING PRETTY QUICKLY FROM NW TO SE ACROSS THE REGION. ONLY
AREA OF CONSIDERABLE CLOUDINESS AT 2 PM WAS OVER THE FAR SE PLAINS.
Q WAS BUBBLING OVER THE S MTNS. TEMPS WERE IN THE 40S OVER THE
PLAINS WHERE THERE WAS SUN...AND 30S WHERE IT WAS CLOUDY. THE SLV
WAS IN THE 50S.
REST OF TODAY INTO TONIGHT...
RIDGING WILL BUILD OVER THE FCST AREA AND SKIES WILL CONTINUE TO
CLEAR. A FEW CONVECTIVE SHOWERS WILL BE POSSIBLE OVER THE SAN JUANS
AND S MTNS THE REST OF THIS AFTERNOON AND EARLY EVENING. OTHERWISE
EXPECT CLEARING SKIES.
THE ONLY CONCERN I HAVE FOR TONIGHT WILL BE PATCHY GROUND FOG IN
PLACES. BASED ON CURRENT RH PROGS...BEST CHANCE FOR SOME FOG WILL BE
OVER THE FAR E PLAINS...MAINLY ALONG THE ARK RVR. TEMPS TONIGHT WILL
BE COOL WITH U20S TO L30S ACROSS THE PLAINS...AND 20S VALLEYS.
THURSDAY...
500 MB RIDGE AXIS WILL BE OVER THE STATE BY LATE AFTERNOON.
TEMP-WISE...TOMORROW WILL BE QUITE A NICE DAY WITH HIGHS IN THE L70S
MOST OF THE PLAINS WITH 60S IN THE VALLEYS. SKIES WILL BE MOSTLY
SUNNY. NO PRECIP IS EXPECTED.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 313 PM MDT WED APR 3 2013
SOME ADJUSTMENTS NEEDED DURING THE LONGER TERM WITH MAIN
METEOROLOGICAL ISSUES CONTINUING TO BE TEMPERATURES...GUSTY WINDS
AT TIMES...ELEVATED FIRE WEATHER CONCERNS FROM FRIDAY AFTERNOON
INTO FRIDAY EVENING...THUNDERSTORM THREAT OVER PORTIONS OF THE FAR
EASTERN PLAINS...ESPECIALLY FROM SUNDAY EVENING INTO SUNDAY NIGHT
AND FINALLY THE IMPACT THAT UPPER SYSTEM WILL PRODUCE OVER THE
FORECAST DISTRICT EARLY NEXT WEEK.
IT STILL APPEARS THE RELATIVELY BENIGN AND MILD TO WARM
METEOROLOGICAL CONDITIONS SHOULD BE NOTED OVER THE CWFA INTO
FRIDAY...THANKS TO A TRANSITORY UPPER RIDGE MOVING ACROSS THE AREA.
IN ADDITION...ELEVATED FIRE CONCERNS ARE STILL ANTICIPATED FROM
FRIDAY AFTERNOON INTO FRIDAY EVENING...ESPECIALLY OVER PORTIONS OF
FIRE WEATHER ZONES 222/224/225/228>233 AND 235 DUE TO PROJECTED
LOW MINIMUM RELATIVE HUMIDITIES AND GUSTY WINDS AT TIMES.
AS TOUCHED UPON IN PREVIOUS DISCUSSIONS...UPPER LEVEL
DISTURBANCES...IMPACTING PRIMARILY NORTHERN PORTIONS OF THE FORECAST
DISTRICT WITH INCREASED PRECIPITATION CHANCES ARE PROJECTED TO
IMPACT THE CWFA FROM LATER FRIDAY INTO THE WEEKEND...ALLOWING FOR
SOMEWHAT COOLER TEMPERATURES AS WELL AS GUSTY WINDS AT TIMES. IN
ADDITION...INCREASED THUNDERSTORM CHANCES MAY BE NOTED OVER FAR
EASTERN PORTIONS OF THE FORECAST DISTRICT FROM SUNDAY EVENING INTO
SUNDAY NIGHT AS DEEPER ATMOSPHERIC MOISTURE INTERACTS WITH
RELATIVELY HEALTHY 0 TO 6 KM BULK SHEARS.
UPPER TROUGH SHOULD THEN IMPACT THE FORECAST DISTRICT BY EARLY NEXT
WEEK WITH THE HIGHEST POTENTIAL FOR WIDESPREAD PRECIPITATION
PROJECTED FROM LATER MONDAY INTO AT LEAST TUESDAY NIGHT. HAVE PAINTED
GENERALLY SCATTERED POPS DURING THIS TIME-FRAME WITH A POTENTIAL
FOR HEALTHY ACCUMULATING SNOW...ESPECIALLY OVER HIGHER TERRAIN
AREAS. WFO PUEBLO WILL CONTINUE TO MONITOR CLOSELY.
GUSTY WINDS WILL BE POSSIBLE FROM FRIDAY INTO FRIDAY NIGHT AND THEN
AGAIN FROM NEXT TUESDAY INTO TUESDAY NIGHT. WARMEST TEMPERATURES OF
THE LONGER TERM ARE EXPECTED FRIDAY WHILE COOLEST CONDITIONS ARE
ANTICIPATED BY NEXT TUESDAY AND WEDNESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1058 PM MDT WED APR 3 2013
VFR CONDITIONS EXPECTED AT ALL TAF SITES THROUGH THE NEXT 24
HOURS. A MINOR DISTURBANCE MOVING ACROSS NORTHEASTERN COLORADO
WILL SPREAD SOME MID AND HIGH LEVEL MOISTURE ACROSS THE AREA
THROUGH THE EARLY MORNING HOURS. THIS SYSTEM WILL ALSO SEND A
WEAK BACK DOOR FRONT ACROSS THE EASTERN PLAINS THROUGH THE
OVERNIGHT HOURS. LIGHT NORTHERLY WINDS BEHIND WEAK FRONT LOOKS
TO INHIBIT FOG FORMATION ACROSS THE EASTERN PLAINS...WITH A
DIURNAL WIND REGIME EXPECTED ONCE AGAIN THURSDAY AFTERNOON.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...MW
SHORT TERM...HODANISH
LONG TERM...77
AVIATION...MW
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
347 AM EDT Thu Apr 4 2013
...There is a slight risk for severe weather today...
.NEAR TERM [Today]...
The 03 UTC regional surface analysis showed a quasi-stationary front
from north FL, to just south of the LA coast, to the southwest Gulf
of Mexico. While a frontal wave appeared to be developing (as
predicted by the NWP guidance) south of LA, the only low that I was
able to close off appeared to be more of a mesoscale low about
30 miles south of Apalachicola, perhaps leftover from the wake low
that brought some gusty winds to portions of our forecast area
Wednesday afternoon and evening. Vapor imagery and upper air data
showed an approaching trough centered over OK, but there were a few
minor short waves well out ahead of this main system.
All of the statistical and dynamical NWP guidance points to a rainy
day for our region today, though just how much rain, and how stormy,
is rather complicated. Since most of the 00 UTC NWP guidance didn`t
initialize the meso low south of Apalachicola, it`s unclear how well
they will handle the frontal system and main frontal wave developing
to the west. Much of our thinking is based on the recent RAP run,
which did initialize the various features quite well. We expect
quite a bit of light rain early this morning, followed by increasing
heavier showers and thunderstorms later this morning and afternoon
as the low moves inland over the FL Panhandle. The band(s) of
convection will move into our eastern zones this afternoon. Much of
our forecast area is likely to get an additional 1 to
2 inches of rain from this system.
The latest NSSL WRF, NCEP ARW/NMM, and our local 4km WRF show a
couple of impressive tracks of max hourly updraft helicity (in terms
of magnitude and longevity) this afternoon. The same can be said for
integrated graupel. This would imply a threat for isolated supercell
thunderstorms, capable of producing severe hail, damaging wind
gusts, and/or even an isolated tornado. While this threat appears
highest over the Gulf coastal waters and the FL Peninsula, there is
a portion of our forecast area that is at risk as well- mainly along
and south of a line from Apalachicola, through Tallahassee, to Moody
AFB, Valdosta. This threat would be from late morning through mid to
late afternoon. Actually, much of our forecast area is in a "Slight
Risk" (15% probability of severe hail/wind, 5% tornado) of severe
storms, but it may be more difficult to generate severe storms
farther west and north than the section we just discussed, as the
best deep layer moisture, forcing, and the 850mb jet stream will
likely be farther east.
&&
.SHORT TERM [Tonight Through Saturday]...
By this evening, the severe potential, and possibly even the
thunder potential will have diminished greatly from this
afternoon. The only exception may be a few strong storms remaining
across the extreme southeast Big Bend of Florida. Elsewhere light
rain will persist through the night, especially across Georgia
where the upper level shortwave will be able to tap into the best
remaining moisture. A dry slot will likely spread from southwest
to northeast through the night, putting a stop to the rain across
portions of the Florida Panhandle and southeast Alabama. Showers
will come to an end quickly on Friday, but clouds should remain
for much of the day. This will hold temperatures in the 60s
region-wide, with lower 60s possible across portions of central
Georgia. Overnight Friday, temperatures will fall to a few degrees
below seasonal averages, in the middle 40s for most locations. Dry
conditions, mostly clear skies, and seasonal temperatures will
finish off the period on Saturday.
&&
.LONG TERM [Saturday Night through Wednesday]...
The bulk of the extended forecast looks to be dry with gradually
warming temperatures as a ridge of surface high pressure shifts
from over the area on Saturday, to well off the Atlantic coast by
Tuesday. This evolution will set up return flow early in the next
work week, and highs into the 80s look likely.
&&
.AVIATION [Beginning 07Z Thursday]...
Occasional light rain (IFR-MVFR vis) is likely through today and
into tonight. However, scattered +SHRA/TSRA will develop later this
morning, affecting the terminals with locally gusty winds and heavy
downpours until mid to late afternoon. IFR to occasionally LIFR cigs
are likely through this morning. They will gradually lift to low-end
MVFR levels by late morning or early afternoon. The guidance differs
on how long these cigs will persist after 00 UTC tonight, so we will
just keep the MVFR cigs through the end of this TAF package.
&&
.MARINE...
Advisory level conditions are expected ahead of developing low
pressure today. In the wake of the low, another brief round of
advisory conditions are anticipated. Winds and seas will fall
below headline levels by the weekend, and remain that way through
at least early next week under the influence of high pressure.
&&
.FIRE WEATHER...
Moist conditions will persist through Friday, helping to keep ERC
values low. A drier airmass will move into the region Saturday, but
at this time it doesn`t appear that Red Flag conditions are likely,
especially since the winds won`t be very strong and the fuels may be
rather damp.
&&
.HYDROLOGY...
With round 1 of the rain complete, we have seen storm totals thus
far between an inch and an inch and a half across the southeast
Big Bend of Florida and around a half of an inch across portions
of south central Georgia east of the Flint River and along the
Florida Panhandle coast.
The light rain from overnight will continue to gradually spread
north through the first part of the day today. Later today,
another round of moderate to heavy rain is expected, with the bulk
of the rain falling along and east of the Flint and Apalachicola
Rivers. In these locations another 1 to 2 inches will be possible,
with the highest amounts expected across the southeast Big Bend,
in the lower Suwannee River basins. With the eastward shift in
expected rainfall, ensemble guidance suggests that most area
rivers will only flirt with the lower end of Action stage. In
fact, the lower Suwannee appears capable of handling the projected
rainfall without climbing to Action stage for most of our forecast
points. When all is said and done there should be little in the
way of impacts along area rivers this weekend.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 73 56 67 46 76 / 80 60 20 0 0
Panama City 71 57 67 53 74 / 70 40 20 0 0
Dothan 66 51 66 44 74 / 70 50 20 0 0
Albany 64 48 65 45 75 / 80 70 30 0 0
Valdosta 71 55 66 46 76 / 90 70 40 10 0
Cross City 73 62 70 45 78 / 90 80 30 10 0
Apalachicola 70 59 66 52 71 / 70 40 20 0 0
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...Small Craft Advisory until 5 PM EDT Friday for Gulf of Mexico
waters from Destin to the Suwannee River out to 60 NM.
&&
$$
NEAR TERM...Fournier
SHORT TERM...Harrigan
LONG TERM...Lamers
AVIATION...Fournier
MARINE...Harrigan
FIRE WEATHER...Fournier
HYDROLOGY...Harrigan
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
330 AM EDT THU APR 4 2013
.SYNOPSIS...
LOW PRESSURE PASSES SOUTH LATE TODAY AND TONIGHT WITH THE CHANCE FOR
RAIN. MODERATING TEMPERATURES OVER THE WEEKEND. FRONT NEARBY SUNDAY
INTO NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
MDLS COMING IN A BIT FASTER WITH ONSET OF PCPN LATER TDY AS SFC
LOW ORGANIZES ALONG GA/SC COAST. HOWEVER VERY DRY LLVLS WILL BE
BATTLING MOISTURE ADVECTION FROM S. AS SUCH DID NOT GO AS FAST AS
MDLS SUGGEST ONCE INTO S WV PLATEAU. LATEST RAP MDL SEEMS TO HAVE
A BETTER REFLECTION OF CURRENT THINKING AND USED IT AS A GUIDE
THRU 00Z. DO BRING IN HIGH POPS ACROSS SW VA BY 18Z AND THEN
SLOWLY SPREAD N UP THE EASTERN SLOPES TO INCLUDE MUCH OF
POCAHONTAS CO WITH THE CATEGORICAL POPS. HAVE A SHARP GRADIENT
HEADING W...WITH CHC POPS EXTENDING TO CRW- HTS AREA AND UP TOWARD
CKB. FEEL SE OH AND NW LOWLAND CO STAY DRY. HAVE ARND A THIRD OF
AN INCH QPF FOR SW VA AND UP THE EASTERN SLOPES. QUICKLY TAILS OF
W OF I79 CORRIDOR. EXIT BULK OF PCPN BY 06Z TO THE E...WITH
LINGERING CHC POPS FOR S/W TROF AXIS SLIDING THRU.
THERE IS SOME CONCERN FOR WINTRY PCPN AT THE ONSET ACROSS RIDGES
IN POCAHONTAS CO. MDLS INDICATE GOOD WET BULBING ARND 00Z TO
REFLECT SOME WET SN OR MIX POTENTIAL BEFORE SWITCHING TO RA LATER
IN EVE. USED SFC AND MODEL ALOFT TOO TO REFLECT THIS IN WX GRIDS.
WILL KEEP ACCUMULATIONS OUT OF GRIDS FOR NOW THOUGH.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
MODELS IN GOOD AGREEMENT SHOWING SYSTEM PULLING OFF TO THE EAST
EARLY FRIDAY...WITH DRY WEATHER EXPECTED BY MIDDAY. WILL SPEED UP
THE EXODUS OF THE POPS. MOS GUIDANCE FOR HIGHS ON FRIDAY HAS BEEN
TRENDING DOWNWARD...BUT STILL LOOKS TOO HIGH. HAVE UNDERCUT MOS ONCE
AGAIN FOR HIGHS FRIDAY...AND ALSO ON SATURDAY.
A COLD FRONT THEN PUSHES INTO THE AREA ON SUNDAY...BEFORE STALLING
OVER THE AREA. SOME DEBATE AMONG THE MODELS ON WHERE THE FRONT WILL
STALL. CURRENT FORECAST LOOKS LIKE A GOOD COMPROMISE FOR NOW...SO
DID NOT CHANGE WITH THE EXCEPTION OF SLOWING THE ARRIVAL OF THE
SHOWERS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
WAVY FRONT APPROACHES THIS WEEKEND AND THEN HANGS NEARBY THE
BALANCE OF THE PERIOD. RIDGING ADVERTISED FOR EARLY NEXT WEEK OVER
THE PAST FEW DAYS IS ALL BUT GONE...THE GFS STILL AMPLIFYING ONE BUT
ALONG THE E COAST TUE. THAT IS WHEN THE ECMWF IS MARKEDLY DIFFERENT
WITH THE NORTHERN STREAM OVER CANADA...USING EASTERN CANADIAN
TROUGHING TO SINK THE CONFLUENCE...AND FRONTAL ZONE...SWD. THIS
WOULD MAKE THE LATTER PORTION OF THE FCST MUCH WETTER AND COOLER
THAN CURRENTLY CODED. AS PER HPC...IT AND TELECONNECTIONS DEPENDENT
UPON SW CONUS TROUGH WILL PLAY A ROLE IN HOW FAR N THE FRONT IS OVER
THE EASTERN CONUS DAYS 6-7.
DRY WEATHER GIVES WAY TO INCREASING CHANCE FOR SHOWERS NW TO SE DAY
3 NT AND DAY 4 WITH INITIAL APPROACH OF FRONT AND INITIAL UPPER
LEVEL WAVE. KEEP CHANCE THROUGH THE BALANCE OF THE FCST...HIGHEST N
AND NW...LOWEST S AND SE...HAVE HAVE JUST SLIGHT CHANCE EARLY ON.
MORE OR LESS EQUAL CHANCE FOR PRECIPITATION THROUGHOUT THE AREA DAY
7. ALSO INTRODUCED SLIGHT CHANCE FOR THUNDER DURING THE AFTERNOONS
AND EARLY EVENINGS BEGINNING MON AS DEW POINTS INCREASE TO NEAR 50.
BLENDED IN ADJMEXBC FOR HIGHS EARLY ON AND THEN HPC DAYS 6 AND 7
HIGHS AND ALL LOWS. ADJMEXBC APPEARED TOO LOW ON LOWS GIVEN SW
FLOW...RISING DEW POINTS AND CLOUDS.
&&
.AVIATION /08Z THURSDAY THROUGH MONDAY/...
06Z THURSDAY TO 06Z FRIDAY...
LIGHT SURFACE WINDS BECOMING GUSTY AGAIN AFTER 15Z...PARTICULARLY
ACROSS THE HIGHER TERRAIN. A LOW PRESSURE SYSTEM WILL APPROACH
FROM THE SOUTH LATE TDY...ALLOWING RA TO OVERSPREAD SW VA BY 18Z
AND SLOWLY SPREADING N UP THE WV MTNS. THIS WILL CREATE GENERAL MVFR
CONDITIONS ACROSS SOUTHWEST VA 18Z...SOUTHERN WV BY 00Z... AND UP
WV MTNS BY 03Z. KEEP SOUTHEAST OHIO AND NORTHERN WV REMAINING
VFR IN MID DECK. KHTS AND KCRW TRICKY AS THEY WILL BE ON THE NW
FRINGE OF BEST LLVL MOISTURE AND PCPN. WILL KEEP THEM VFR WITH
THIS ISSUANCE BUT ALLOW CIGS TO LWR INTO LOW END VFR. KEPT SHRA
MENTION OUT OF THOSE LOCALES DUE TO LOW CHC AT THIS RANGE.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z FRIDAY...
FORECAST CONFIDENCE...MEDIUM.
ALTERNATE SCENARIOS: LOW PRESSURE SYSTEM MAY SPREAD MOISTURE AND
LOW CIGS FARTHER NORTH THAN CURRENTLY FORECAST TOWARDS THE END OF
THE TAF PERIOD.
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 THU 04/04/13
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z FRIDAY...
NO WIDESPREAD IFR CONDITIONS EXPECTED.
&&
.FIRE WEATHER...
RH VALUES WILL AGAIN DIP INTO TEENS AND 20S PERCENT WISE AS DWPTS
MIX DOWN INTO THE TEENS AND TEMPS CLIMB. MOISTURE ADV FROM S IN
AFTN SHOULD ALLOW RH TO RECOVER UP TO CENTRAL WV WITH RA ACROSS SW
VA. HOWEVER...ACROSS PORTIONS OF NE KY...SE OH AND N WV...THE DRY
AIR WILL PREVAIL TDY. SOME AFTN GUSTS ARND 15 KTS MAY ALSO BE
EXPECTED ACROSS N WV. WITH VERY DRY 10 HR FUELS IN PLACE...AN
ENHANCED FIRE DANGER THREAT MAY BE REALIZED TODAY. CONDITIONS
WILL BE MONITORED AND COORDINATED WITH THE APPROPRIATE STATE
FORESTRY PERSONNEL FOR THE POTENTIAL FOR ANY FIRE WEATHER
STATEMENTS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/RPY/30
NEAR TERM...30
SHORT TERM...RPY
LONG TERM...TRM
AVIATION...30
FIRE WEATHER...30
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
255 AM EDT THU APR 4 2013
.SYNOPSIS...
LOW PRESSURE PASSES SOUTH LATE TODAY AND TONIGHT WITH THE CHANCE FOR
RAIN. MODERATING TEMPERATURES OVER THE WEEKEND. FRONT NEARBY NEXT
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
MDLS COMING IN A BIT FASTER WITH ONSET OF PCPN LATER TDY AS SFC
LOW ORGANIZES ALONG GA/SC COAST. HOWEVER VERY DRY LLVLS WILL BE
BATTLING MOISTURE ADVECTION FROM S. AS SUCH DID NOT GO AS FAST AS
MDLS SUGGEST ONCE INTO S WV PLATEAU. LATEST RAP MDL SEEMS TO HAVE
A BETTER REFLECTION OF CURRENT THINKING AND USED IT AS A GUIDE
THRU 00Z. DO BRING IN HIGH POPS ACROSS SW VA BY 18Z AND THEN
SLOWLY SPREAD N UP THE EASTERN SLOPES TO INCLUDE MUCH OF
POCAHONTAS CO WITH THE CATEGORICAL POPS. HAVE A SHARP GRADIENT
HEADING W...WITH CHC POPS EXTENDING TO CRW- HTS AREA AND UP TOWARD
CKB. FEEL SE OH AND NW LOWLAND CO STAY DRY. HAVE ARND A THIRD OF
AN INCH QPF FOR SW VA AND UP THE EASTERN SLOPES. QUICKLY TAILS OF
W OF I79 CORRIDOR. EXIT BULK OF PCPN BY 06Z TO THE E...WITH
LINGERING CHC POPS FOR S/W TROF AXIS SLIDING THRU.
THERE IS SOME CONCERN FOR WINTRY PCPN AT THE ONSET ACROSS RIDGES
IN POCAHONTAS CO. MDLS INDICATE GOOD WET BULBING ARND 00Z TO
REFLECT SOME WET SN OR MIX POTENTIAL BEFORE SWITCHING TO RA LATER
IN EVE. USED SFC AND MODEL ALOFT TOO TO REFLECT THIS IN WX GRIDS.
WILL KEEP ACCUMULATIONS OUT OF GRIDS FOR NOW THOUGH.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
STILL SOME DISAGREEMENT IN THE MODELS WITH TRACK AND TIMING OF
THE SURFACE LOW FOR THURSDAY NIGHT INTO FRIDAY. NAM HAS TRENDED
MUCH FATHER SOUTH...BUT HAS THE SURFACE LOW AROUND THE MOUTH OF
CHESAPEAKE BAY...WHILE GFS AND ECMWF SHOW AN ELONGATED LOW FROM
THE CHESAPEAKE DOWN TO SOUTH CAROLINA. WITH THE NAM TRENDING SOUTH
TIGHTENED THE GRADIENT IN POPS ACROSS OUR CWA...GOING DRY ALONG
AND NW OF THE OHIO RIVER WHILE KEEPING LIKELY IN SW VA AND THE
SOUTHERN COAL FIELDS AND SOUTHERN AND CENTRAL MOUNTAINS OF WV.
PRECIP IS ALSO FASTER EXITING OUR CWA...SO TRENDED THAT WAY WITH
POPS AS ANOTHER SURFACE HIGH MOVES IN FRIDAY NIGHT. ONLY SMALL
CHANGES MADE ON TEMPS THURSDAY NIGHT THROUGH FRIDAY NIGHT...BUT
DID INCREASE HIGHS SOME ON SATURDAY WITH PLENTY OF APRIL SUNSHINE.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
WAVY FRONT APPROACHES THIS WEEKEND AND THEN HANGS NEARBY THE
BALANCE OF THE PERIOD. RIDGING ADVERTISED FOR EARLY NEXT WEEK OVER
THE PAST FEW DAYS IS ALL BUT GONE...THE GFS STILL AMPLIFYING ONE BUT
ALONG THE E COAST TUE. THAT IS WHEN THE ECMWF IS MARKEDLY DIFFERENT
WITH THE NORTHERN STREAM OVER CANADA...USING EASTERN CANADIAN
TROUGHING TO SINK THE CONFLUENCE...AND FRONTAL ZONE...SWD. THIS
WOULD MAKE THE LATTER PORTION OF THE FCST MUCH WETTER AND COOLER
THAN CURRENTLY CODED. AS PER HPC...IT AND TELECONNECTIONS DEPENDENT
UPON SW CONUS TROUGH WILL PLAY A ROLE IN HOW FAR N THE FRONT IS OVER
THE EASTERN CONUS DAYS 6-7.
DRY WEATHER GIVES WAY TO INCREASING CHANCE FOR SHOWERS NW TO SE DAY
3 NT AND DAY 4 WITH INITIAL APPROACH OF FRONT AND INITIAL UPPER
LEVEL WAVE. KEEP CHANCE THROUGH THE BALANCE OF THE FCST...HIGHEST N
AND NW...LOWEST S AND SE...HAVE HAVE JUST SLIGHT CHANCE EARLY ON.
MORE OR LESS EQUAL CHANCE FOR PRECIPITATION THROUGHOUT THE AREA DAY
7. ALSO INTRODUCED SLIGHT CHANCE FOR THUNDER DURING THE AFTERNOONS
AND EARLY EVENINGS BEGINNING MON AS DEW POINTS INCREASE TO NEAR 50.
BLENDED IN ADJMEXBC FOR HIGHS EARLY ON AND THEN HPC DAYS 6 AND 7
HIGHS AND ALL LOWS. ADJMEXBC APPEARED TOO LOW ON LOWS GIVEN SW
FLOW...RISING DEW POINTS AND CLOUDS.
&&
.AVIATION /07Z THURSDAY THROUGH MONDAY/...
06Z THURSDAY TO 06Z FRIDAY...
LIGHT SURFACE WINDS BECOMING GUSTY AGAIN AFTER 15Z...PARTICULARLY
ACROSS THE HIGHER TERRAIN. A LOW PRESSURE SYSTEM WILL APPROACH
FROM THE SOUTH LATE TDY...ALLOWING RA TO OVERSPREAD SW VA BY 18Z
AND SLOWLY SPREADING N UP THE WV MTNS. THIS WILL CREATE GENERAL MVFR
CONDITIONS ACROSS SOUTHWEST VA 18Z...SOUTHERN WV BY 00Z... AND UP
WV MTNS BY 03Z. KEEP SOUTHEAST OHIO AND NORTHERN WV REMAINING
VFR IN MID DECK. KHTS AND KCRW TRICKY AS THEY WILL BE ON THE NW
FRINGE OF BEST LLVL MOISTURE AND PCPN. WILL KEEP THEM VFR WITH
THIS ISSUANCE BUT ALLOW CIGS TO LWR INTO LOW END VFR. KEPT SHRA
MENTION OUT OF THOSE LOCALES DUE TO LOW CHC AT THIS RANGE.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z FRIDAY...
FORECAST CONFIDENCE...MEDIUM.
ALTERNATE SCENARIOS: LOW PRESSURE SYSTEM MAY SPREAD MOISTURE AND
LOW CIGS FARTHER NORTH THAN CURRENTLY FORECAST TOWARDS THE END OF
THE TAF PERIOD.
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 THU 04/04/13
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z FRIDAY...
NO WIDESPREAD IFR CONDITIONS EXPECTED.
&&
.FIRE WEATHER...
RH VALUES WILL AGAIN DIP INTO TEENS AND 20S PERCENT WISE AS DWPTS
MIX DOWN INTO THE TEENS AND TEMPS CLIMB. MOISTURE ADV FROM S IN
AFTN SHOULD ALLOW RH TO RECOVER UP TO CENTRAL WV WITH RA ACROSS SW
VA. HOWEVER...ACROSS PORTIONS OF NE KY...SE OH AND N WV...THE DRY
AIR WILL PREVAIL TDY. SOME AFTN GUSTS ARND 15 KTS MAY ALSO BE
EXPECTED ACROSS N WV. WITH VERY DRY 10 HR FUELS IN PLACE...AN
ENHANCED FIRE DANGER THREAT MAY BE REALIZED TODAY. CONDITIONS
WILL BE MONITORED AND COORDINATED WITH THE APPROPRIATE STATE
FORESTRY PERSONNEL FOR THE POTENTIAL FOR ANY FIRE WEATHER
STATEMENTS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/RPY/30
NEAR TERM...30
SHORT TERM...MZ
LONG TERM...TRM
AVIATION...30
FIRE WEATHER...30
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
505 AM EDT THU APR 4 2013
.SYNOPSIS...
LOW PRESSURE WAS OVER THE NORTHERN GULF OF MEXICO THIS MORNING
WITH HIGH PRESSURE OVER THE MID ATLANTIC REGION. THE LOW WILL MOVE
ACROSS GEORGIA AND FLORIDA TODAY THEN OFF THE CAROLINA COAST BY
FRIDAY MORNING. HIGH PRESSURE WILL COVER THE REGION BEHIND THIS
SYSTEM FOR SATURDAY AND SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 430 AM EDT THURSDAY...
STARTING WITH SURFACE DEW POINTS IN THE SINGLE DIGITS AND TEENS
AND A LOT OF ROOM TO COOL DOWN TO THE WET BULB AS MOISTURE
INCREASES FROM THE TOP DOWN. LATEST RUNS OF THE RAP AND LOCAL WRF
SUGGEST SLOW PROGRESS OF THE LEADING EDGE OF THE PRECIPITATION
INTO THE DRY AIR. HAVE SLOWED DOWN THE ARRIVAL TIME IN THE
NORTHERN COUNTY WARNING AREA TODAY.
FOR PRECIPITATION TYPE...BUFKIT FORECAST SOUNDINGS ALONG THE
SOUTHERN BLUE RIDGE SHOW SNOW AND SLEET FOR MUCH OF THE DAY. HAVE
ISSUED A WINTER WEATHER ADVISORY FOR WATAUGA COUNTY...EXPECTING
THE HIGHEST SNOW AND SLEET AMOUNTS ALONG THE AVERY COUNTY LINE.
BEECH MOUNTAIN MAY HAVE 3 INCHES OF NEW SNOW/SLEET TODAY.
AS PRECIPITATION MOVES INTO THE FORECAST AREA THIS
MORNING...IN-SITU WEDGE FORMS. ALREADY STARTING OUT CLOUDY AND
WITH PRECIPITATION TEMPERATURES WILL REMAIN BELOW NORMAL. USED A
NON DIURNAL TREND FOR HOURLY TEMPERATURES.
BEST ISENTROPIC LIFT AND UPPER DIFFLUENCE CROSS THROUGH THE AREA
AREA BETWEEN 18Z/2PM AND 06Z/2AM. PROBABILITY OF PRECIPITATION
BEGINS TO LOWER IN THE MOUNTAINS AS THE LOW COMING ACROSS THE GULF
COAST STATES MOVES OFFSHORE AND WINDS COME AROUND TO THE
NORTHWEST.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
AS OF 400 AM EDT THURSDAY...
BY SUNRISE FRIDAY...THE GFS AND ECMWF FORECAST MODELS ARE IN DECENT
AGREEMENT THAT THE LOW PRESSURE SYSTEM WHICH BROUGHT RAIN TO OUR
AREA EARLIER IN THE NIGHT WILL BE MOVING RAPIDLY UP THE NORTH
CAROLINA COAST. AS THE LOW CONTINUES NORTHEAST...WINDS ACROSS OUR
AREA WILL BECOME INCREASINGLY NORTHWESTERLY...DRAWING DRIER AIR IN
FROM THE GREAT LAKES. AS SUCH...SHOWER ACTIVITY WILL TAPER OFF
THROUGH THE MORNING...AND EXPECT TO SEE CLOUD COVER BREAK UP FROM
WEST TO EAST DURING THE AFTERNOON.
A RIDGE OF HIGH PRESSURE WILL PASS ACROSS THE APPALACHIAN CHAIN
FRIDAY NIGHT...AND WILL MOVE OFF OF THE ATLANTIC COAST SATURDAY
AFTERNOON. DESPITE ABUNDANT AFTERNOON SUNSHINE...EASTERLY WINDS
FLOWING AROUND THE DEPARTING HIGH PRESSURE RIDGE WILL CARRY COOLER
AIR FROM THE ATLANTIC INTO OUR AREA. THEREFORE...UNDERCUT GUIDANCE
BY A FEW DEGREES FOR SATURDAY AFTERNOON TEMPERATURES...LIMITING
HIGHS TO THE UPPER 50S AND THE LOW 60S FOR MOST OF THE AREA.
BY SUNDAY...AN UPPER LEVEL TROUGH BEGINS TO SET IN ACROSS THE
WESTERN HALF OF THE UNITED STATES...ALLOWING UPPER LEVEL RIDGING
ACROSS THE EASTERN HALF TO BECOME INCREASINGLY AMPLIFIED. AS
SUCH...SUNDAY AFTERNOON TEMPERATURES WILL BE AMONG THE WARMEST
EXPERIENCED THIS YEAR...WITH HIGHS REACHING TO NEAR 70 ACROSS THE
PIEDMONTS...AND INTO THE MID/UPPER 60S ACROSS THE MOUNTAINS. A COLD
FRONT WILL SINK FROM THE GREAT LAKES AS FAR SOUTH AS THE OHIO RIVER
VALLEY DURING THE AFTERNOON...HOWEVER ANOTHER DEVELOPING LOW
PRESSURE SYSTEM ACROSS THE PLAINS WILL CAUSE THE FRONT TO STALL
BEFORE REACHING INTO OUR AREA.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 400 AM EDT THURSDAY...
THE LONG TERM PERIOD WILL BE CHARACTERIZED BY BUILDING 500MB
HEIGHTS...INCREASING MOISTURE...AND WARMER TEMPERATURES AS A WESTERN
U.S. TROF CONTINUES TO DEEPEN.
UPPER LEVEL HEIGHTS WILL REALLY BEGIN TO RISE MONDAY AS THE WESTERN
TROF DEEPENS. THE 00Z ECMWF APPEARS TOO FAR EAST WITH THIS
SYSTEM...AND LEANED TOWARD THE CANADIAN/GFS MODELS KEEPING A
SOUTHWEST FLOW OVER OUR AREA RESULTING IN OUR FIRST TASTE OF ABOVE
NORMAL TEMPERATURES IN WEEKS. MEANWHILE...AT THE SFC...
SOUTH/SOUTHWEST WINDS USHER IN HIGHER DEWPOINTS...DEEPER MOISTURE
WITH PWATS 1-2 STANDARD DEVIATIONS ABOVE NORMAL...TUESDAY AND
WEDNESDAY. WEAK UPPER LEVEL WAVES IN ADVANCE OF THE DEEPENING TROF
INTERACTING WITH THIS INCREASING MOISTURE WILL BRING A SLIGHT CHANCE
OF SHOWERS TUESDAY AND WEDNESDAY. THE 12Z GFS SUGGESTS A DRIER DAY
TUESDAY WITH A MORE AMPLIFIED PATTERN COMPARED TO PREVIOUS MODEL
RUNS...KEEPING THE BEST UPPER LEVEL SUPPORT/LOW LEVEL CONVERGENCE
WELL WEST OF OUR AREA.
A DEEP SOUTHWEST FLOW WILL KEEP ABOVE NORMAL TEMPS...MOSTLY CLOUDY
SKIES AND A RISK OF SHOWERS/ISOLATED STORMS ON WEDNESDAY.
&&
.AVIATION /09Z THURSDAY THROUGH MONDAY/...
AS OF 140 AM EDT THURSDAY...
CEILINGS WILL LOWER OVER VIRGINIA AND THE CAROLINAS AS DEEPER
MOISTURE MOVES NORTHEAST OUT OF THE TENNESSEE VALLEY. RAIN ARRIVES
AFTER 18Z/2PM WITH MVFR CEILINGS BY 00Z/8PM. MEDIUM CONFIDENCE ON
THE TIMING OF THE RAIN AND MVFR CONDITIONS.
RAIN AND MVFR TO IFR CEILINGS AND VISIBILITIES ARE EXPECTED
OVERNIGHT. EASTERLY SURFACE AND LOW LEVEL WINDS WILL LIKELY BRING
IFR CONDITIONS TO ROA/LYH AND DAN AFTER 06Z.
BY FRIDAY THE STORM SYSTEM WILL BE OFF THE EAST COAST. LOW LEVEL
MOISTURE WILL REMAIN OVER THE MOUNTAINS...RESULTING IN PROLONGED
MVFR CEILINGS AT LWB/BLF. CONDITIONS WILL BE GRADUALLY IMPROVING
EAST OF THE BLUE RIDGE BY LATE FRIDAY.
HIGH PRESSURE WILL THEN BUILD IN FOR SATURDAY...BRINGING DRY
WEATHER AND RETURNING ALL TAF LOCATIONS TO VFR THROUGH MONDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...WINTER WEATHER ADVISORY UNTIL 6 PM EDT THIS EVENING FOR NCZ018.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...NF
LONG TERM...NF/PH
AVIATION...AMS
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
1000 AM EDT Thu Apr 4 2013
.NEAR TERM [Rest of Today]...
Updated at: 1000 AM EDT
Early indications this morning are that severe weather potential is
becoming increasingly marginal for today across our area. Limiting
factors include:
1. Cirrus shield currently spread north from convection over the
C/EC Gulf of Mexico that may limit heating, or delay the
scattering of low cloud decks
2. A pronounced inversion around 650mb (via 12z TAE sounding) due
to the arrival of an EML aloft.
3. Deeper moisture situated well to the south over the Gulf and
the Florida peninsula.
Essentially, the atmosphere is going to have to do a lot of work in
order to be more conducive for severe thunderstorms, and that is
looking less and less likely with time in our forecast area. 12z RAP
analysis shows that at 700mb, the pocket of warmest air is actually
situated just overhead at the moment. Meanwhile, a subtle shortwave
and jet max aloft near the Louisiana coastline (per water vapor) was
propagating ENE, and RAP analysis suggested that 700mb temperatures
were about 2-3C cooler near this feature. Therefore, it`s possible
that as mid-level height falls commence and stronger upper level
forcing arrives, that the inversion layer aloft will slowly erode.
However, even 2-3C of cooling in that layer would still leave us
with a rather marginal instability profile. What would be most
likely would be shallow rain showers with isolated thunderstorms,
increasing in coverage for a brief time as the shortwave approaches.
Extrapolation of the shortwave would take it into our area around
18-21z. The changes that were made to the grids to account for all
this was to reduce the sensible weather across most of the area to
just rain showers with isolated thunderstorms, and time the peak in
PoPs more for the early to mid afternoon.
Despite all of these factors, it is not possible to totally rule out
a stronger storm or two this afternoon. There is still a fair amount
of uncertainty in the assessment of various mesoscale features, so
we will continue to highlight a risk of severe storms in the HWO.
Any strong or severe storms, however, should be rather isolated.
&&
.SHORT TERM [Tonight Through Saturday]...
By this evening, the severe potential, and possibly even the thunder
potential will have diminished greatly from this afternoon. The only
exception may be a few strong storms remaining across the extreme
southeast Big Bend of Florida. Elsewhere light rain will persist
through the night, especially across Georgia where the upper level
shortwave will be able to tap into the best remaining moisture. A
dry slot will likely spread from southwest to northeast through the
night, putting a stop to the rain across portions of the Florida
Panhandle and southeast Alabama. Showers will come to an end quickly
on Friday, but clouds should remain for much of the day. This will
hold temperatures in the 60s region-wide, with lower 60s possible
across portions of central Georgia. Overnight Friday, temperatures
will fall to a few degrees below seasonal averages, in the middle
40s for most locations. Dry conditions, mostly clear skies, and
seasonal temperatures will finish off the period on Saturday.
&&
.LONG TERM [Saturday Night through Wednesday]...
The bulk of the extended forecast looks to be dry with gradually
warming temperatures as a ridge of surface high pressure shifts from
over the area on Saturday, to well off the Atlantic coast by
Tuesday. This evolution will set up return flow early in the next
work week, and highs into the 80s look likely.
&&
.AVIATION [through 12 UTC Friday]...
Occasional light rain is likely this morning. However, scattered
+SHRA/TSRA will develop later this morning, affecting KECP, KTLH,
and KVLD with locally gusty winds and heavy downpours until mid
afternoon. LIFR-IFR cigs will gradually lift to low-end MVFR levels
by late morning or early afternoon. Although most of the rain will
move east of the region later this afternoon, IFR-LIFR cigs are
likely to return to all terminals tonight.
&&
.MARINE...
Advisory level conditions are expected ahead of developing low
pressure today. In the wake of the low, another brief round of
advisory conditions are anticipated. Winds and seas will fall below
headline levels by the weekend, and remain that way through at least
early next week under the influence of high pressure.
&&
.FIRE WEATHER...
Moist conditions will persist through Friday, helping to keep ERC
values low. A drier airmass will move into the region Saturday, but
at this time it doesn`t appear that Red Flag conditions are likely,
especially since the winds won`t be very strong and the fuels may be
rather damp.
&&
.HYDROLOGY...
With round 1 of the rain complete, we have seen storm totals thus
far between an inch and an inch and a half across the southeast Big
Bend of Florida and around a half of an inch across portions of
south central Georgia east of the Flint River and along the Florida
Panhandle coast.
The light rain from overnight will continue to gradually spread
north through the first part of the day today. Later today,
another round of moderate to heavy rain is expected, with the bulk
of the rain falling along and east of the Flint and Apalachicola
Rivers. In these locations another 1 to 2 inches will be possible,
with the highest amounts expected across the southeast Big Bend,
in the lower Suwannee River basins. With the eastward shift in
expected rainfall, ensemble guidance suggests that most area
rivers will only flirt with the lower end of Action stage. In
fact, the lower Suwannee appears capable of handling the projected
rainfall without climbing to Action stage for most of our forecast
points. When all is said and done there should be little in the
way of impacts along area rivers this weekend.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 73 56 67 46 76 / 50 40 20 0 0
Panama City 71 57 67 53 74 / 40 40 20 0 0
Dothan 66 51 66 44 74 / 30 40 20 0 0
Albany 64 48 65 45 75 / 40 40 30 0 0
Valdosta 71 55 66 46 76 / 50 40 40 10 0
Cross City 73 62 70 45 78 / 40 50 30 10 0
Apalachicola 70 59 66 52 71 / 40 30 20 0 0
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...Small Craft Advisory until 5 PM EDT Friday for Gulf of Mexico
waters from Destin to the Suwannee River out to 60 NM.
&&
$$
NEAR TERM...Lamers
SHORT TERM...Harrigan
LONG TERM...Lamers
AVIATION...Fournier
MARINE...Harrigan
FIRE WEATHER...Fournier
HYDROLOGY...Harrigan
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
630 AM EDT Thu Apr 4 2013
...There is a slight risk for severe weather today...
.NEAR TERM [Today]...
The 03 UTC regional surface analysis showed a quasi-stationary front
from north FL, to just south of the LA coast, to the southwest Gulf
of Mexico. While a frontal wave appeared to be developing (as
predicted by the NWP guidance) south of LA, the only low that I was
able to close off appeared to be more of a mesoscale low about
30 miles south of Apalachicola, perhaps leftover from the wake low
that brought some gusty winds to portions of our forecast area
Wednesday afternoon and evening. Vapor imagery and upper air data
showed an approaching trough centered over OK, but there were a few
minor short waves well out ahead of this main system.
All of the statistical and dynamical NWP guidance points to a rainy
day for our region today, though just how much rain, and how stormy,
is rather complicated. Since most of the 00 UTC NWP guidance didn`t
initialize the meso low south of Apalachicola, it`s unclear how well
they will handle the frontal system and main frontal wave developing
to the west. Much of our thinking is based on the recent RAP run,
which did initialize the various features quite well. We expect
quite a bit of light rain early this morning, followed by increasing
heavier showers and thunderstorms later this morning and afternoon
as the low moves inland over the FL Panhandle. The band(s) of
convection will move into our eastern zones this afternoon. Much of
our forecast area is likely to get an additional 1 to
2 inches of rain from this system.
The latest NSSL WRF, NCEP ARW/NMM, and our local 4km WRF show a
couple of impressive tracks of max hourly updraft helicity (in terms
of magnitude and longevity) this afternoon. The same can be said for
integrated graupel. This would imply a threat for isolated supercell
thunderstorms, capable of producing severe hail, damaging wind
gusts, and/or even an isolated tornado. While this threat appears
highest over the Gulf coastal waters and the FL Peninsula, there is
a portion of our forecast area that is at risk as well- mainly along
and south of a line from Apalachicola, through Tallahassee, to Moody
AFB, Valdosta. This threat would be from late morning through mid to
late afternoon. Actually, much of our forecast area is in a "Slight
Risk" (15% probability of severe hail/wind, 5% tornado) of severe
storms, but it may be more difficult to generate severe storms
farther west and north than the section we just discussed, as the
best deep layer moisture, forcing, and the 850mb jet stream will
likely be farther east.
&&
.SHORT TERM [Tonight Through Saturday]...
By this evening, the severe potential, and possibly even the
thunder potential will have diminished greatly from this
afternoon. The only exception may be a few strong storms remaining
across the extreme southeast Big Bend of Florida. Elsewhere light
rain will persist through the night, especially across Georgia
where the upper level shortwave will be able to tap into the best
remaining moisture. A dry slot will likely spread from southwest
to northeast through the night, putting a stop to the rain across
portions of the Florida Panhandle and southeast Alabama. Showers
will come to an end quickly on Friday, but clouds should remain
for much of the day. This will hold temperatures in the 60s
region-wide, with lower 60s possible across portions of central
Georgia. Overnight Friday, temperatures will fall to a few degrees
below seasonal averages, in the middle 40s for most locations. Dry
conditions, mostly clear skies, and seasonal temperatures will
finish off the period on Saturday.
&&
.LONG TERM [Saturday Night through Wednesday]...
The bulk of the extended forecast looks to be dry with gradually
warming temperatures as a ridge of surface high pressure shifts
from over the area on Saturday, to well off the Atlantic coast by
Tuesday. This evolution will set up return flow early in the next
work week, and highs into the 80s look likely.
&&
.AVIATION [through 12 UTC Friday]...
Occasional light rain is likely this morning. However, scattered
+SHRA/TSRA will develop later this morning, affecting KECP, KTLH,
and KVLD with locally gusty winds and heavy downpours until mid
afternoon. LIFR-IFR cigs will gradually lift to low-end MVFR levels
by late morning or early afternoon. Although most of the rain will
move east of the region later this afternoon, IFR-LIFR cigs are
likely to return to all terminals tonight.
&&
.MARINE...
Advisory level conditions are expected ahead of developing low
pressure today. In the wake of the low, another brief round of
advisory conditions are anticipated. Winds and seas will fall
below headline levels by the weekend, and remain that way through
at least early next week under the influence of high pressure.
&&
.FIRE WEATHER...
Moist conditions will persist through Friday, helping to keep ERC
values low. A drier airmass will move into the region Saturday, but
at this time it doesn`t appear that Red Flag conditions are likely,
especially since the winds won`t be very strong and the fuels may be
rather damp.
&&
.HYDROLOGY...
With round 1 of the rain complete, we have seen storm totals thus
far between an inch and an inch and a half across the southeast
Big Bend of Florida and around a half of an inch across portions
of south central Georgia east of the Flint River and along the
Florida Panhandle coast.
The light rain from overnight will continue to gradually spread
north through the first part of the day today. Later today,
another round of moderate to heavy rain is expected, with the bulk
of the rain falling along and east of the Flint and Apalachicola
Rivers. In these locations another 1 to 2 inches will be possible,
with the highest amounts expected across the southeast Big Bend,
in the lower Suwannee River basins. With the eastward shift in
expected rainfall, ensemble guidance suggests that most area
rivers will only flirt with the lower end of Action stage. In
fact, the lower Suwannee appears capable of handling the projected
rainfall without climbing to Action stage for most of our forecast
points. When all is said and done there should be little in the
way of impacts along area rivers this weekend.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 73 56 67 46 76 / 80 60 20 0 0
Panama City 71 57 67 53 74 / 70 40 20 0 0
Dothan 66 51 66 44 74 / 70 50 20 0 0
Albany 64 48 65 45 75 / 80 70 30 0 0
Valdosta 71 55 66 46 76 / 90 70 40 10 0
Cross City 73 62 70 45 78 / 90 80 30 10 0
Apalachicola 70 59 66 52 71 / 70 40 20 0 0
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...Small Craft Advisory until 5 PM EDT Friday for Gulf of Mexico
waters from Destin to the Suwannee River out to 60 NM.
&&
$$
NEAR TERM...Fournier
SHORT TERM...Harrigan
LONG TERM...Lamers
AVIATION...Fournier
MARINE...Harrigan
FIRE WEATHER...Fournier
HYDROLOGY...Harrigan
AREA FORECAST DISCUSSION
NWS GAYLORD MI
935 AM EDT THU APR 4 2013
.SYNOPSIS...
ISSUED AT 420 AM EDT THU APR 4 2013
A COLD FRONT WILL MOVE THROUGH NORTHERN MICHIGAN TODAY.
PRECIPITATION ASSOCIATED WITH THIS FRONT WILL START AS SNOW THIS
MORNING...BUT MIX WITH RAIN AS THE TEMPERATURES RISE ABOVE
FREEZING TODAY. THE RAIN WILL END IN THE AFTERNOON AS DRIER TAKES
OVER BEFORE THE FRONT MOVES THROUGH. HIGH PRESSURE AND COOLER
TEMPERATURES WILL SETTLE IN FOR THURSDAY NIGHT AND FRIDAY BEFORE A
STORM SYSTEM MOVES INTO NORTHERN MICHIGAN AND HANGS AROUND FOR
MUCH OF THE WEEKEND...BRINGING RAIN AND SNOW MIXED FOR SATURDAY
AND SUNDAY.
&&
.UPDATE...
ISSUED AT 933 AM EDT THU APR 4 2013
CURRENT RADAR AND SFC OBS SHOWING AREA OF PCPN OVER ERN UPPER AND
STRAITS REGION...WHICH IS IN RESPONSE TO A COLD FRONT PUSHING INTO
THE WRN LAKES. PCPN ASSOCIATED WITH THIS FRONT SO FAR THIS MORNING
HAS BEEN CONFINED TO A NARROW BAND...HINDERED GREATLY BY LIMITED
MSTR. SFC DEW PTS SOUTH OF THE STRAITS ARE CURRENTLY IN THE
TEENS...THOUGH DEW PTS HAVE INCREASED INTO THE LOWER AND MID 20 OVER
ERN UPPER JUST IN ADVANCE OF THE FRONT.
AS FOR THE REST OF TODAY...LIMITED MSTR WILL REMAIN A HINDRANCE
THROUGH THE AFTERNOON OVR NRN LWR MI...KEEPING ANY PCPN CONFINED TO
A NARROW AREA RIGHT ALONG THE FRONT. MODEL SOUNDINGS SHOW PCPN CHCS
ENDING FROM GLR NORTH BTWN 18Z AND 21Z...AND ENDING NEAR SAGINAW BAY
REGION BETWEEN 00Z AND 03Z.
OVERALL CURRENT FCST IN LINE WITH MILD TEMP AND SUN EARLY OVER THE
SRN CWA...WITH PCPN ENDING OVER ERN UPPER EARLY THIS AFTN.
UPDATE ISSUED AT 607 AM EDT THU APR 4 2013
CHANGES THIS HOUR: HAVE CONTINUED SLOWING TREND OF POPS THROUGH
MUCH OF TODAY GIVEN RECENT GOOD AGREEMENT BETWEEN THE NAM/RAP/HRRR
GIVEN VERY IMPRESSIVE PERFORMANCE FROM THE RAP OVER THE PAST FEW
HOURS. SNOWFALL HAS ARRIVED FROM SAW-ERY-ANJ AND WILL GO AHEAD AND
BUMP UP NEAR TERM POPS TO CATEGORICAL FOR NORTHERN CHIPPEWA
THROUGH DAYBREAK. BEYOND THIS...INITIAL SURGE OF ISENTROPIC ASCENT
ALONG LLEVEL MOISTURE AXIS WILL SHIFT EAST AND WE/LL THEN AWAIT
FURTHER DEVELOPMENT ALONG THE FRONTAL BOUNDARY ITSELF...WHICH IS
NOW SLIDING SOUTHEAST THROUGH WESTERN UPPER. DON/T EXPECT THIS TO
BE SUBSTANTIAL...AND AS PREVIOUSLY MENTIONED...EXPECT IT TO
DWINDLE AS IT HEADS SOUTH...WITH RAIN GRADUALLY TAKING OVER AS THE
PREDOMINATE PRECIPITATION TYPE.
COULD SEE AN INCH OF MORNING ACCUMS FROM PARADISE TO ANJ /WEBCAMS
SHOW A COATING ATTM/...SO WATCH OUT FOR SOME SLICK AM TRAVEL IN
THESE SPOTS.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 420 AM EDT THU APR 4 2013
HIGH IMPACT WEATHER POTENTIAL: GALE FORCE WINDS OVER MUCH OF
NORTHERN LAKE MICHIGAN THROUGH MID MORNING. WILL LIKELY HAVE SOME
COASTAL WIND GUSTS ABOVE 30 MPH TODAY...OTHERWISE...NO HIGH
IMPACT WEATHER EXPECTED.
OVERVIEW: SURFACE MAP EARLY THIS MORNING REVEALS HIGH PRESSURE
RESPONSIBLE FOR THE BEAUTIFUL /ALBEIT CHILLY/ AFTERNOON YESTERDAY
HAVING PUSHED SOUTH AND EAST INTO THE OHIO VALLEY/MID ATLANTIC
REGION...THIS HAS ALLOWED BROAD SOUTHWESTERLY FLOW TO DEVELOP BETWEEN
THIS FEATURE AND RATHER IMPRESSIVE SURFACE LOW NOW TRAVELING FROM
WEST TO EAST ACROSS NORTHERN ONTARIO. PRIMARY FEATURE OF NOTE
THROUGH THE SHORT TERM PORTION OF THE FORECAST IS A COLD FRONT
DRAPED TO THE SOUTH AND WEST OF THIS LOW...APPROACHING LAKE SUPERIOR
AS OF THIS WRITING. STRENGTHENING SOUTHWESTERLY WINDS OVER NORTHERN
MICHIGAN HAVE PRECLUDED STEEP TEMPERATURE FALLS OVERNIGHT WITH MOST
LOCATIONS AT LEAST 10F WARMER THAN 24 HOURS AGO. LLEVEL MOISTURE
HAS NOT RESPONDED IN TANDEM...WITH 00Z APX RAOB SHOWING A PALTRY
0.14" PWAT. CLOSER TO THE FRONT...HOWEVER...PRECIPITATION ECHOES
HAVE BEEN BLOSSOMING OVER THE PAST COUPLE OF HOURS AS ROBUST LOW
LEVEL JET AT H8 /50KTS+/ TRANSPORTS A PLUME OF 2/3" PWATS RAPIDLY
EASTWARD.
THROUGH DAYBREAK: WINDS CONTINUE TO RAMP UP FROM WEST TO EAST...WITH
SLOWLY INCREASING MID AND UPPER LEVEL CLOUDINESS...PRIMARILY FROM THE
STRAITS NORTH. TIMING AREA OF INCREASING RADAR ECHOES SUGGESTS
PRECIPITATION COULD ARRIVE AS EARLY AS 5-6AM OVER EASTERN UPPER AS
SOME SNOW SHOWERS. INTERESTING TO NOTE SURFACE DEWPOINT TREND OVER
THE PAST FEW HOURS OVER NORTHERN LOWER...WITH VALUES PLUMMETING TO
BELOW 10F AT TVC/CAD AND ROPPING EVERYWHERE AWAY FROM LAKE
MICHIGAN. THIS SUGGESTS THE SLOWING TREND IN FRONTAL PRECIP
ARRIVAL /SEEN IN RECENT RENDTIONS OF THE HRRR/RAP/ ARE LIKELY ON
THE RIGHT TRACK.
TODAY: COLD FRONT PUSHES THROUGH NORTHERN MICHIGAN TODAY...STARTING
THE DAY OVER WESTERN UPPER AND REACHING MY SOUTHEASTERN ZONES BY
EVENING. PRIMARY CONCERNS TODAY CENTER AROUND PRECIPITATION
CHANCES AS THIS BOUNDARY MOVES THROUGH...AS WELL AS THE STRENGTH
OF SOUTHWESTERLY WINDS AHEAD OF IT.
TRAJECTORY ANALYSIS SHOWS LLEVEL SOURCE REGION FOR AIR OVER NORTHERN
LOWER TODAY COMES FROM THE IOWA/ILLINOIS REGION 24 HOURS AGO...AN
AREA FEATURING A DEARTH OF LLEVEL MOISTURE. SO...BOUNDARY WILL BE
FIGHTING INCREASINGLY DRY ATMOSPHERE AS IT PUSHES SOUTH AND EAST
WITH LLEVEL MOISTURE TONGUE THINNING. LLEVEL CONVERGENCE IS
MODEST...BUT WILL HAVE SOME HELP FROM AN ARRIVING JET MAX /AND ITS
ASSOCIATED RIGHT ENTRANCE REGION/ AS WELL AS CONTINUED ISENTROPIC
ASCENT. NET RESULT: EXPECT A BROKEN LINE OF SHOWERS TO SINK SOUTH
DURING THE DAY...WEAKENING AS THEY DO SO. RECENT MODEL TRENDS HAVE
CONTINUED TO SLOW THE SOUTHWARD MOVEMENT OF ANY PRECIPITATION...
AND WHILE THIS FORECAST REPRESENTS A SLOWING TREND...IT COULD
REQUIRE FURTHER SLOWING WITH PRECIITATION POTENTIALLY COMPLETELY
FALLING APART BEFORE MAKING IT MUCH SOUTH OF M-32.
PTYPE: STARTS THE DAY ALL SNOW...BUT RAPIDLY WARMING SURFACE LAYER
SUGGESTS PREDOMINATE TYPE TO SWITCH TO RAIN COASTAL LOCALES BY LATE
MORNING AND ALL AREAS BY AFTERNOON. ONLY CAVEAT TO THIS WILL BE
OVER THE INTERIOR HIGH SPOTS WHERE WET BULBS IN THE MID 30S INDICATE
A FEW SNOWFLAKES MIGHT MIX IN AT ANY TIME...ESP IF PRECIPITATION
RATES ARE DECENT. OVERALL VERY LITTLE IMPACT EXPECTED...HOWEVER...
OUTSIDE OF A FEW SLICK SPOTS TO START THE DAY FROM THE BRIDGE
NORTH. PAVEMENT TEMPS WILL BE TOO WARM TO SUPPORT ANY ICING BY MID
MORNING OVER NORTHERN LOWER.
WINDS: PRETTY MUCH FULLY FORCED BY THE STRENGTH OF THE LOW LEVEL
JET /40-50KTS AT H9 EARLY...WEAKENING AS IT HEADS SOUTH/ AND THE
AMOUNT OF MIXING WE CAN DEVELOP AHEAD OF THE BOUNDARY. GIVEN A
SOMEWHAT SLOWER ARRIVAL TO THE BOUNDARY...MIXING HEIGHTS SHOULD GET
A CHANCE TO BUILD EARLY...WITH MOMENTUM TRANSPORT SUGGESTING WE CAN
LIKELY TAP 30KTS. SO...EXPECT SOUTHWEST WINDS 15-25 MPH WITH GUSTS
OVER 30 MPH BY LATE MORNING AND THROUGH THE AFTERNOON OVER
NORTHERN LOWER...A LITTLE WEAKER THAN THIS FURTHER NORTH.
TEMPS: T9 ROCKETS TO JUST ABOVE FREEZING AHEAD OF THE BOUNDARY...
WITH THE POTENTIAL TO PRODUCE LOW-MID 50S AHEAD OF THE BOUNDARY.
COMPLICATING THIS WILL BE CLOUDS AND PRECIP...WHICH...WITH PRETTY
SUBSTANTIAL LLEVEL DEWPOINT DEPRESSIONS SUGGESTS AMPLE OPPORTUNITY
FOR EVAPORATIONAL COOLING. WILL ALLOW SOUTHEASTERN ZONES TO MAKE A
RUN AT 55...WITH LOCALES NORTH OF THIS GENERALLY IN THE MID-UPPER
40S.
TONIGHT: NORTHWEST WINDS WILL USHER COLDER AIR INTO THE REGION AS
HIGH PRESSURE BUILDS IN FROM THE NORTHERN PLAINS. T8 FALLS TO -12C
SOUTH/-15C NORTH AFTER MIDNIGHT...WHICH WITH A MINOR AMOUNT OF
RESIDUAL 850-700MB MOISTURE SUGGESTS THAT SOME LAKE RESPONSE MAY TRY
AND GET GOING...BUT NOT UNTIL THE VERY END OF THIS PERIOD. WILL
CARRY CHANCE POPS AFTER 09Z BUT NO SIGNIFICANT SNOWFALL EXPECTED.
TEMPERATURES LOOK TO FALL INTO THE MID 20S AS COLD AIR ADVECTION IS
OFFSET SOMEWHAT BY RESIDUAL WINDS AND SOME LAKE CLOUDINESS /NORTH/.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 420 AM EDT THU APR 4 2013
FRIDAY...INITIALLY, THERE WILL BE SOME LIGHT SNOW AND FLURRIES IN E
UPPER, MAINLY NEAR WHITEFISH POINT AS THE 850 MB TEMPERATURES FALL
TO AROUND -14C WITH ABOUT 50% RH IN THE 850-700 MB LAYER. THIS WILL
BE MAINLY IN THE MORNING, BECAUSE AS THE HIGH PRESSURE BUILDS INTO
THE REGION MORE DRY AIR PUSHES INTO THE FORECAST AREA, AND THE 850
MB TEMPERATURES RISE ABOVE -12C BY 18Z. SO WILL GO WITH A DRY DAY
OVERALL.
FRIDAY NIGHT...THE WARM ADVECTION WING FROM THE NEXT SYSTEM BEGINS
TO MOVE INTO THE REGION, ESPECIALLY AFTER 06Z. THIS WILL BRING A
CHANCE OF SNOW BY 12Z IN THE WESTERN PART OF THE FORECAST AREA. THE
LOWER LEVEL MOISTURE WILL BE THE MAIN CONCERN AS THE POPS ARE DRAWN
ROUGHLY WHERE THE 850 MB MOISTURE IS ABOVE 50%. HOWEVER, THIS COULD
JUST AS EASILY BE NOTHING UNTIL THE DAY ON SATURDAY, IF THE ATMOSPHERE
DOESN`T SATURATE FAST ENOUGH.
SATURDAY...THE WARM FRONT MOVES NORTH A BIT, BUT FOR THE MOISTURE
PART ONCE IT GETS TO AROUND THE STRAITS, IT LOOKS LIKE IT TRAVELS
EAST, WITH THE SFC LOW FOLLOWING ALONG IT. THIS SETS UP SNOW IN E
UPPER, WHICH COULD HAVE LIGHT TO MODERATE AMOUNTS THROUGH THE DAY.
WOULD EXPECT A MIX, ESPECIALLY BETWEEN M-32 AND THE STRAITS AS THE
PROFILES ARE EITHER ON THE 0C LINE. SOUTH OF M-32, THINK THAT IT
WILL BE MAINLY RAIN. OVERNIGHT, THE WARMER AIR WITH BOTH MODELS,
GETS TO THE STRAITS, THE RAIN WILL LIKELY GET ALL THE WAY TO THE
STRAITS, AND WE`LL GET A MIX IN E UPPER. THE CONCERN, BASED ON THE
PROFILES OF BOTH MODELS, IS THAT WE WILL PARTIALLY MELT SOME OF
THE SNOW (TEMPERATURES IN THE PROFILE GET TO +2C AROUND 850 MB
THEN FALL TO OR BELOW 0C IN E UPPER). SO WILL GO WITH SNOW/RAIN OR
FREEZING RAIN MIX AT THIS POINT, AND KEEP IT MENTIONED IN HWOAPX.
THE COLD AIR MOVES INTO E UPPER AGAIN ONCE THE LOW MOVES EAST. SO
E UPPER WILL SEE A CHANGE OVER AGAIN BETWEEN 06Z AND 12Z.
EXTENDED (SUNDAY THROUGH WEDNESDAY)...SUNDAY, THE MODELS MOVE THE
LOW EAST OF THE REGION AND THE COLD AIR MOVES BACK. HOWEVER, THINGS
ARE DRY ENOUGH AND WARM ENOUGH, THAT LITTLE IF NO PRECIPITATION WILL
FALL. MONDAY, LOOKS LIKE ANOTHER WAVE FORMS ON THE FRONT THAT
STALLS IT, AND EVEN ALLOWS FOR SOME WARMING. SO WILL GO WITH
CHANCE OF RAIN IN N LOWER AND A MIX IN E UPPER. TUESDAY, THE LOW
NO LONGER MOVES OUT OF THE MID MISSISSIPPI VALLEY AS THE MODELS
FOCUS DEVELOPMENT ON THE CLOSED 500 MB LOW IN THE SOUTHWEST
STATES. THIS WOULD KEEP THE SFC LOW IN TX/OK REGION WITH A WARM
FRONT/SFC TROUGH THAT IS STALLED IN THE OHIO VALLEY. OVERNIGHT,
THE GFS BEGINS TO LIFT THE 500 MB LOW INTO THE NORTHERN BRANCH.
THE ECMWF LOOKS BETTER WITH THE SLOWER LIFTING OF THE WAVE KEEPING
THE RAIN AND THE WARM FRONT ALONG OR SOUTH OF THE OHIO VALLEY.
WEDNESDAY, THINKING THAT THE GFS IS TOO WET, DUE TO THE PHASING OF
THE SYSTEMS. WOULD BE MORE INCLINED TO GO WITH THE ECMWF IDEA WITH
THE HIGH SETTLING IN OVER THE GREAT LAKES. WHICH WOULD KEEP US
DRY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 640 AM EDT THU APR 4 2013
SUMMARY: A MOISTURE-STARVED COLD FRONT WILL DROP THROUGH THE STATE
TODAY...BRINGING A LINE OF RAIN AND SNOW SHOWERS. HIGH PRESSURE
WILL BUILD IN BEHIND THIS FRONT TONIGHT...WITH SOME LAKE INDUCED
CLOUDINESS DEVELOPING.
RESTRICTIONS: EXPECT APN/TVC/MBL TO REMAIN VFR THROUGH THE UPCOMING
TAF PERIOD...WITH A BRIEF PERIOD OF MVFR STILL EXPECTED THIS
AFTERNOON /ALBEIT SOMEWHAT LATER THAN PREVIOUSLY EXPECTED/ AT PLN.
EXPECT SHRASN TO IMPACT THIS SITE WITH MVFR CIGS DEVELOPING AFTER
21Z IMMEDIATELY BEHIND THE DEPARTING COLD FRONT. THESE CLOUDS WILL
LIFT DURING THE EVENING WITH VFR CLOUDINESS /4KFT/ OVERNIGHT.
WINDS: SOUTHWEST WINDS WILL STRENGTHEN TO 15G25KTS FOR THE BY MID
MORNING AND CONTINUE THROUGH THE AFTERNOON WHILE GRADUALLY VEERING
WEST. LATE THIS AFTERNOON WILL SHIFT NORTHWESTERLY AND DIMINISH TO
AROUND 10KTS THIS EVENING AND OVERNIGHT.
LLWS: SOUTHWEST WINDS AT 1.5-2KFT STILL REACHING AROUND 40 KTS AND
GIVEN THAT THE TERMINALS REMAIN SOMEWHAT DECOUPLED FROM THIS
STRONGER FLOW ALOFT...WILL LEAVE LLWS MENTION IN THROUGH 14Z BEFORE
DAYTIME MIXING ELIMINATES ANY POTENTIAL SHEAR LAYERS.
&&
.MARINE...
ISSUED AT 420 AM EDT THU APR 4 2013
SUMMARY: A COLD FRONT WILL PUSH THROUGH NORTHERN MICHIGAN TODAY WITH
GUSTY SOUTHWEST WINDS AHEAD OF IT SHIFTING NORTHWESTERLY BEHIND IT
THIS EVENING AS HIGH PRESSURE BUILDS INTO THE GREAT LAKES REGION.
HIGH PRESSURE WILL REMAIN IN CONTROL OF OUR WEATHER THROUGH FRIDAY
NIGHT.
HEADLINES: GALE WARNING THROUGH LATE MORNING STILL LOOKS GOOD OVER
PORTIONS OF NORTHERN LAKE MICHIGAN. ELSEWHERE...WILL EXPAND SMALL
CRAFTS TO ALL ZONES FOR TODAY GIVEN ROBUST WIND FIELD AHEAD OF
APPROACHING COLD FRONT. MARGINAL SMALL CRAFT CONDITIONS CONTINUE
THROUGH TONIGHT BEFORE A BREAK IN WIND/WAVE ACTIVITY IS EXPECTED
FRIDAY. NEXT STORM SYSTEM ARRIVES SATURDAY WITH A RENEWED PERIOD OF
SMALL CRAFTS LIKELY THROUGHOUT THE NEARSHORE WATERS OF NORTHERN
MICHIGAN.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR
LHZ345>349.
LM...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR LMZ323-
345-346.
GALE WARNING UNTIL 11 AM EDT THIS MORNING FOR LMZ341-342-344.
LS...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR LSZ321-
322.
&&
$$
UPDATE...SR
SYNOPSIS...JL
SHORT TERM...ARNOTT
LONG TERM...JL
AVIATION...ARNOTT
MARINE...ARNOTT
AREA FORECAST DISCUSSION...UPDATED
NWS GAYLORD MI
642 AM EDT THU APR 4 2013
.SYNOPSIS...
ISSUED AT 420 AM EDT THU APR 4 2013
A COLD FRONT WILL MOVE THROUGH NORTHERN MICHIGAN TODAY.
PRECIPITATION ASSOCIATED WITH THIS FRONT WILL START AS SNOW THIS
MORNING...BUT MIX WITH RAIN AS THE TEMPERATURES RISE ABOVE
FREEZING TODAY. THE RAIN WILL END IN THE AFTERNOON AS DRIER TAKES
OVER BEFORE THE FRONT MOVES THROUGH. HIGH PRESSURE AND COOLER
TEMPERATURES WILL SETTLE IN FOR THURSDAY NIGHT AND FRIDAY BEFORE A
STORM SYSTEM MOVES INTO NORTHERN MICHIGAN AND HANGS AROUND FOR
MUCH OF THE WEEKEND...BRINGING RAIN AND SNOW MIXED FOR SATURDAY
AND SUNDAY.
&&
.UPDATE...
ISSUED AT 607 AM EDT THU APR 4 2013
CHANGES THIS HOUR: HAVE CONTINUED SLOWING TREND OF POPS THROUGH
MUCH OF TODAY GIVEN RECENT GOOD AGREEMENT BETWEEN THE NAM/RAP/HRRR
GIVEN VERY IMPRESSIVE PERFORMANCE FROM THE RAP OVER THE PAST FEW
HOURS. SNOWFALL HAS ARRIVED FROM SAW-ERY-ANJ AND WILL GO AHEAD AND
BUMP UP NEAR TERM POPS TO CATEGORICAL FOR NORTHERN CHIPPEWA
THROUGH DAYBREAK. BEYOND THIS...INITIAL SURGE OF ISENTROPIC ASCENT
ALONG LLEVEL MOISTURE AXIS WILL SHIFT EAST AND WE/LL THEN AWAIT
FURTHER DEVELOPMENT ALONG THE FRONTAL BOUNDARY ITSELF...WHICH IS
NOW SLIDING SOUTHEAST THROUGH WESTERN UPPER. DON/T EXPECT THIS TO
BE SUBSTANTIAL...AND AS PREVIOUSLY MENTIONED...EXPECT IT TO
DWINDLE AS IT HEADS SOUTH...WITH RAIN GRADUALLY TAKING OVER AS THE
PREDOMINATE PRECIPITATION TYPE.
COULD SEE AN INCH OF MORNING ACCUMS FROM PARADISE TO ANJ /WEBCAMS
SHOW A COATING ATTM/...SO WATCH OUT FOR SOME SLICK AM TRAVEL IN
THESE SPOTS.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 420 AM EDT THU APR 4 2013
HIGH IMPACT WEATHER POTENTIAL: GALE FORCE WINDS OVER MUCH OF
NORTHERN LAKE MICHIGAN THROUGH MID MORNING. WILL LIKELY HAVE SOME
COASTAL WIND GUSTS ABOVE 30 MPH TODAY...OTHERWISE...NO HIGH
IMPACT WEATHER EXPECTED.
OVERVIEW: SURFACE MAP EARLY THIS MORNING REVEALS HIGH PRESSURE
RESPONSIBLE FOR THE BEAUTIFUL /ALBEIT CHILLY/ AFTERNOON YESTERDAY
HAVING PUSHED SOUTH AND EAST INTO THE OHIO VALLEY/MID ATLANTIC
REGION...THIS HAS ALLOWED BROAD SOUTHWESTERLY FLOW TO DEVELOP BETWEEN
THIS FEATURE AND RATHER IMPRESSIVE SURFACE LOW NOW TRAVELING FROM
WEST TO EAST ACROSS NORTHERN ONTARIO. PRIMARY FEATURE OF NOTE
THROUGH THE SHORT TERM PORTION OF THE FORECAST IS A COLD FRONT
DRAPED TO THE SOUTH AND WEST OF THIS LOW...APPROACHING LAKE SUPERIOR
AS OF THIS WRITING. STRENGTHENING SOUTHWESTERLY WINDS OVER NORTHERN
MICHIGAN HAVE PRECLUDED STEEP TEMPERATURE FALLS OVERNIGHT WITH MOST
LOCATIONS AT LEAST 10F WARMER THAN 24 HOURS AGO. LLEVEL MOISTURE
HAS NOT RESPONDED IN TANDEM...WITH 00Z APX RAOB SHOWING A PALTRY
0.14" PWAT. CLOSER TO THE FRONT...HOWEVER...PRECIPITATION ECHOES
HAVE BEEN BLOSSOMING OVER THE PAST COUPLE OF HOURS AS ROBUST LOW
LEVEL JET AT H8 /50KTS+/ TRANSPORTS A PLUME OF 2/3" PWATS RAPIDLY
EASTWARD.
THROUGH DAYBREAK: WINDS CONTINUE TO RAMP UP FROM WEST TO EAST...WITH
SLOWLY INCREASING MID AND UPPER LEVEL CLOUDINESS...PRIMARILY FROM THE
STRAITS NORTH. TIMING AREA OF INCREASING RADAR ECHOES SUGGESTS
PRECIPITATION COULD ARRIVE AS EARLY AS 5-6AM OVER EASTERN UPPER AS
SOME SNOW SHOWERS. INTERESTING TO NOTE SURFACE DEWPOINT TREND OVER
THE PAST FEW HOURS OVER NORTHERN LOWER...WITH VALUES PLUMMETING TO
BELOW 10F AT TVC/CAD AND ROPPING EVERYWHERE AWAY FROM LAKE
MICHIGAN. THIS SUGGESTS THE SLOWING TREND IN FRONTAL PRECIP
ARRIVAL /SEEN IN RECENT RENDTIONS OF THE HRRR/RAP/ ARE LIKELY ON
THE RIGHT TRACK.
TODAY: COLD FRONT PUSHES THROUGH NORTHERN MICHIGAN TODAY...STARTING
THE DAY OVER WESTERN UPPER AND REACHING MY SOUTHEASTERN ZONES BY
EVENING. PRIMARY CONCERNS TODAY CENTER AROUND PRECIPITATION
CHANCES AS THIS BOUNDARY MOVES THROUGH...AS WELL AS THE STRENGTH
OF SOUTHWESTERLY WINDS AHEAD OF IT.
TRAJECTORY ANALYSIS SHOWS LLEVEL SOURCE REGION FOR AIR OVER NORTHERN
LOWER TODAY COMES FROM THE IOWA/ILLINOIS REGION 24 HOURS AGO...AN
AREA FEATURING A DEARTH OF LLEVEL MOISTURE. SO...BOUNDARY WILL BE
FIGHTING INCREASINGLY DRY ATMOSPHERE AS IT PUSHES SOUTH AND EAST
WITH LLEVEL MOISTURE TONGUE THINNING. LLEVEL CONVERGENCE IS
MODEST...BUT WILL HAVE SOME HELP FROM AN ARRIVING JET MAX /AND ITS
ASSOCIATED RIGHT ENTRANCE REGION/ AS WELL AS CONTINUED ISENTROPIC
ASCENT. NET RESULT: EXPECT A BROKEN LINE OF SHOWERS TO SINK SOUTH
DURING THE DAY...WEAKENING AS THEY DO SO. RECENT MODEL TRENDS HAVE
CONTINUED TO SLOW THE SOUTHWARD MOVEMENT OF ANY PRECIPITATION...
AND WHILE THIS FORECAST REPRESENTS A SLOWING TREND...IT COULD
REQUIRE FURTHER SLOWING WITH PRECIITATION POTENTIALLY COMPLETELY
FALLING APART BEFORE MAKING IT MUCH SOUTH OF M-32.
PTYPE: STARTS THE DAY ALL SNOW...BUT RAPIDLY WARMING SURFACE LAYER
SUGGESTS PREDOMINATE TYPE TO SWITCH TO RAIN COASTAL LOCALES BY LATE
MORNING AND ALL AREAS BY AFTERNOON. ONLY CAVEAT TO THIS WILL BE
OVER THE INTERIOR HIGH SPOTS WHERE WET BULBS IN THE MID 30S INDICATE
A FEW SNOWFLAKES MIGHT MIX IN AT ANY TIME...ESP IF PRECIPITATION
RATES ARE DECENT. OVERALL VERY LITTLE IMPACT EXPECTED...HOWEVER...
OUTSIDE OF A FEW SLICK SPOTS TO START THE DAY FROM THE BRIDGE
NORTH. PAVEMENT TEMPS WILL BE TOO WARM TO SUPPORT ANY ICING BY MID
MORNING OVER NORTHERN LOWER.
WINDS: PRETTY MUCH FULLY FORCED BY THE STRENGTH OF THE LOW LEVEL
JET /40-50KTS AT H9 EARLY...WEAKENING AS IT HEADS SOUTH/ AND THE
AMOUNT OF MIXING WE CAN DEVELOP AHEAD OF THE BOUNDARY. GIVEN A
SOMEWHAT SLOWER ARRIVAL TO THE BOUNDARY...MIXING HEIGHTS SHOULD GET
A CHANCE TO BUILD EARLY...WITH MOMENTUM TRANSPORT SUGGESTING WE CAN
LIKELY TAP 30KTS. SO...EXPECT SOUTHWEST WINDS 15-25 MPH WITH GUSTS
OVER 30 MPH BY LATE MORNING AND THROUGH THE AFTERNOON OVER
NORTHERN LOWER...A LITTLE WEAKER THAN THIS FURTHER NORTH.
TEMPS: T9 ROCKETS TO JUST ABOVE FREEZING AHEAD OF THE BOUNDARY...
WITH THE POTENTIAL TO PRODUCE LOW-MID 50S AHEAD OF THE BOUNDARY.
COMPLICATING THIS WILL BE CLOUDS AND PRECIP...WHICH...WITH PRETTY
SUBSTANTIAL LLEVEL DEWPOINT DEPRESSIONS SUGGESTS AMPLE OPPORTUNITY
FOR EVAPORATIONAL COOLING. WILL ALLOW SOUTHEASTERN ZONES TO MAKE A
RUN AT 55...WITH LOCALES NORTH OF THIS GENERALLY IN THE MID-UPPER
40S.
TONIGHT: NORTHWEST WINDS WILL USHER COLDER AIR INTO THE REGION AS
HIGH PRESSURE BUILDS IN FROM THE NORTHERN PLAINS. T8 FALLS TO -12C
SOUTH/-15C NORTH AFTER MIDNIGHT...WHICH WITH A MINOR AMOUNT OF
RESIDUAL 850-700MB MOISTURE SUGGESTS THAT SOME LAKE RESPONSE MAY TRY
AND GET GOING...BUT NOT UNTIL THE VERY END OF THIS PERIOD. WILL
CARRY CHANCE POPS AFTER 09Z BUT NO SIGNIFICANT SNOWFALL EXPECTED.
TEMPERATURES LOOK TO FALL INTO THE MID 20S AS COLD AIR ADVECTION IS
OFFSET SOMEWHAT BY RESIDUAL WINDS AND SOME LAKE CLOUDINESS /NORTH/.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 420 AM EDT THU APR 4 2013
FRIDAY...INITIALLY, THERE WILL BE SOME LIGHT SNOW AND FLURRIES IN E
UPPER, MAINLY NEAR WHITEFISH POINT AS THE 850 MB TEMPERATURES FALL
TO AROUND -14C WITH ABOUT 50% RH IN THE 850-700 MB LAYER. THIS WILL
BE MAINLY IN THE MORNING, BECAUSE AS THE HIGH PRESSURE BUILDS INTO
THE REGION MORE DRY AIR PUSHES INTO THE FORECAST AREA, AND THE 850
MB TEMPERATURES RISE ABOVE -12C BY 18Z. SO WILL GO WITH A DRY DAY
OVERALL.
FRIDAY NIGHT...THE WARM ADVECTION WING FROM THE NEXT SYSTEM BEGINS
TO MOVE INTO THE REGION, ESPECIALLY AFTER 06Z. THIS WILL BRING A
CHANCE OF SNOW BY 12Z IN THE WESTERN PART OF THE FORECAST AREA. THE
LOWER LEVEL MOISTURE WILL BE THE MAIN CONCERN AS THE POPS ARE DRAWN
ROUGHLY WHERE THE 850 MB MOISTURE IS ABOVE 50%. HOWEVER, THIS COULD
JUST AS EASILY BE NOTHING UNTIL THE DAY ON SATURDAY, IF THE ATMOSPHERE
DOESN`T SATURATE FAST ENOUGH.
SATURDAY...THE WARM FRONT MOVES NORTH A BIT, BUT FOR THE MOISTURE
PART ONCE IT GETS TO AROUND THE STRAITS, IT LOOKS LIKE IT TRAVELS
EAST, WITH THE SFC LOW FOLLOWING ALONG IT. THIS SETS UP SNOW IN E
UPPER, WHICH COULD HAVE LIGHT TO MODERATE AMOUNTS THROUGH THE DAY.
WOULD EXPECT A MIX, ESPECIALLY BETWEEN M-32 AND THE STRAITS AS THE
PROFILES ARE EITHER ON THE 0C LINE. SOUTH OF M-32, THINK THAT IT
WILL BE MAINLY RAIN. OVERNIGHT, THE WARMER AIR WITH BOTH MODELS,
GETS TO THE STRAITS, THE RAIN WILL LIKELY GET ALL THE WAY TO THE
STRAITS, AND WE`LL GET A MIX IN E UPPER. THE CONCERN, BASED ON THE
PROFILES OF BOTH MODELS, IS THAT WE WILL PARTIALLY MELT SOME OF
THE SNOW (TEMPERATURES IN THE PROFILE GET TO +2C AROUND 850 MB
THEN FALL TO OR BELOW 0C IN E UPPER). SO WILL GO WITH SNOW/RAIN OR
FREEZING RAIN MIX AT THIS POINT, AND KEEP IT MENTIONED IN HWOAPX.
THE COLD AIR MOVES INTO E UPPER AGAIN ONCE THE LOW MOVES EAST. SO
E UPPER WILL SEE A CHANGE OVER AGAIN BETWEEN 06Z AND 12Z.
EXTENDED (SUNDAY THROUGH WEDNESDAY)...SUNDAY, THE MODELS MOVE THE
LOW EAST OF THE REGION AND THE COLD AIR MOVES BACK. HOWEVER, THINGS
ARE DRY ENOUGH AND WARM ENOUGH, THAT LITTLE IF NO PRECIPITATION WILL
FALL. MONDAY, LOOKS LIKE ANOTHER WAVE FORMS ON THE FRONT THAT
STALLS IT, AND EVEN ALLOWS FOR SOME WARMING. SO WILL GO WITH
CHANCE OF RAIN IN N LOWER AND A MIX IN E UPPER. TUESDAY, THE LOW
NO LONGER MOVES OUT OF THE MID MISSISSIPPI VALLEY AS THE MODELS
FOCUS DEVELOPMENT ON THE CLOSED 500 MB LOW IN THE SOUTHWEST
STATES. THIS WOULD KEEP THE SFC LOW IN TX/OK REGION WITH A WARM
FRONT/SFC TROUGH THAT IS STALLED IN THE OHIO VALLEY. OVERNIGHT,
THE GFS BEGINS TO LIFT THE 500 MB LOW INTO THE NORTHERN BRANCH.
THE ECMWF LOOKS BETTER WITH THE SLOWER LIFTING OF THE WAVE KEEPING
THE RAIN AND THE WARM FRONT ALONG OR SOUTH OF THE OHIO VALLEY.
WEDNESDAY, THINKING THAT THE GFS IS TOO WET, DUE TO THE PHASING OF
THE SYSTEMS. WOULD BE MORE INCLINED TO GO WITH THE ECMWF IDEA WITH
THE HIGH SETTLING IN OVER THE GREAT LAKES. WHICH WOULD KEEP US
DRY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 640 AM EDT THU APR 4 2013
SUMMARY: A MOISTURE-STARVED COLD FRONT WILL DROP THROUGH THE STATE
TODAY...BRINGING A LINE OF RAIN AND SNOW SHOWERS. HIGH PRESSURE
WILL BUILD IN BEHIND THIS FRONT TONIGHT...WITH SOME LAKE INDUCED
CLOUDINESS DEVELOPING.
RESTRICTIONS: EXPECT APN/TVC/MBL TO REMAIN VFR THROUGH THE UPCOMING
TAF PERIOD...WITH A BRIEF PERIOD OF MVFR STILL EXPECTED THIS
AFTERNOON /ALBEIT SOMEWHAT LATER THAN PREVIOUSLY EXPECTED/ AT PLN.
EXPECT SHRASN TO IMPACT THIS SITE WITH MVFR CIGS DEVELOPING AFTER
21Z IMMEDIATELY BEHIND THE DEPARTING COLD FRONT. THESE CLOUDS WILL
LIFT DURING THE EVENING WITH VFR CLOUDINESS /4KFT/ OVERNIGHT.
WINDS: SOUTHWEST WINDS WILL STRENGTHEN TO 15G25KTS FOR THE BY MID
MORNING AND CONTINUE THROUGH THE AFTERNOON WHILE GRADUALLY VEERING
WEST. LATE THIS AFTERNOON WILL SHIFT NORTHWESTERLY AND DIMINISH TO
AROUND 10KTS THIS EVENING AND OVERNIGHT.
LLWS: SOUTHWEST WINDS AT 1.5-2KFT STILL REACHING AROUND 40 KTS AND
GIVEN THAT THE TERMINALS REMAIN SOMEWHAT DECOUPLED FROM THIS
STRONGER FLOW ALOFT...WILL LEAVE LLWS MENTION IN THROUGH 14Z BEFORE
DAYTIME MIXING ELIMINATES ANY POTENTIAL SHEAR LAYERS.
&&
.MARINE...
ISSUED AT 420 AM EDT THU APR 4 2013
SUMMARY: A COLD FRONT WILL PUSH THROUGH NORTHERN MICHIGAN TODAY WITH
GUSTY SOUTHWEST WINDS AHEAD OF IT SHIFTING NORTHWESTERLY BEHIND IT
THIS EVENING AS HIGH PRESSURE BUILDS INTO THE GREAT LAKES REGION.
HIGH PRESSURE WILL REMAIN IN CONTROL OF OUR WEATHER THROUGH FRIDAY
NIGHT.
HEADLINES: GALE WARNING THROUGH LATE MORNING STILL LOOKS GOOD OVER
PORTIONS OF NORTHERN LAKE MICHIGAN. ELSEWHERE...WILL EXPAND SMALL
CRAFTS TO ALL ZONES FOR TODAY GIVEN ROBUST WIND FIELD AHEAD OF
APPROACHING COLD FRONT. MARGINAL SMALL CRAFT CONDITIONS CONTINUE
THROUGH TONIGHT BEFORE A BREAK IN WIND/WAVE ACTIVITY IS EXPECTED
FRIDAY. NEXT STORM SYSTEM ARRIVES SATURDAY WITH A RENEWED PERIOD OF
SMALL CRAFTS LIKELY THROUGHOUT THE NEARSHORE WATERS OF NORTHERN
MICHIGAN.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR
LHZ345>349.
LM...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR LMZ323-
345-346.
GALE WARNING UNTIL 11 AM EDT THIS MORNING FOR LMZ341-342-344.
LS...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR LSZ321-
322.
&&
$$
UPDATE...ARNOTT
SYNOPSIS...JL
SHORT TERM...ARNOTT
LONG TERM...JL
AVIATION...ARNOTT
MARINE...ARNOTT
AREA FORECAST DISCUSSION...UPDATED
NWS GAYLORD MI
614 AM EDT THU APR 4 2013
.SYNOPSIS...
ISSUED AT 420 AM EDT THU APR 4 2013
A COLD FRONT WILL MOVE THROUGH NORTHERN MICHIGAN TODAY.
PRECIPITATION ASSOCIATED WITH THIS FRONT WILL START AS SNOW THIS
MORNING...BUT MIX WITH RAIN AS THE TEMPERATURES RISE ABOVE
FREEZING TODAY. THE RAIN WILL END IN THE AFTERNOON AS DRIER TAKES
OVER BEFORE THE FRONT MOVES THROUGH. HIGH PRESSURE AND COOLER
TEMPERATURES WILL SETTLE IN FOR THURSDAY NIGHT AND FRIDAY BEFORE A
STORM SYSTEM MOVES INTO NORTHERN MICHIGAN AND HANGS AROUND FOR
MUCH OF THE WEEKEND...BRINGING RAIN AND SNOW MIXED FOR SATURDAY
AND SUNDAY.
&&
.UPDATE...
ISSUED AT 607 AM EDT THU APR 4 2013
CHANGES THIS HOUR: HAVE CONTINUED SLOWING TREND OF POPS THROUGH
MUCH OF TODAY GIVEN RECENT GOOD AGREEMENT BETWEEN THE NAM/RAP/HRRR
GIVEN VERY IMPRESSIVE PERFORMANCE FROM THE RAP OVER THE PAST FEW
HOURS. SNOWFALL HAS ARRIVED FROM SAW-ERY-ANJ AND WILL GO AHEAD AND
BUMP UP NEAR TERM POPS TO CATEGORICAL FOR NORTHERN CHIPPEWA
THROUGH DAYBREAK. BEYOND THIS...INITIAL SURGE OF ISENTROPIC ASCENT
ALONG LLEVEL MOISTURE AXIS WILL SHIFT EAST AND WE/LL THEN AWAIT
FURTHER DEVELOPMENT ALONG THE FRONTAL BOUNDARY ITSELF...WHICH IS
NOW SLIDING SOUTHEAST THROUGH WESTERN UPPER. DON/T EXPECT THIS TO
BE SUBSTANTIAL...AND AS PREVIOUSLY MENTIONED...EXPECT IT TO
DWINDLE AS IT HEADS SOUTH...WITH RAIN GRADUALLY TAKING OVER AS THE
PREDOMINATE PRECIPITATION TYPE.
COULD SEE AN INCH OF MORNING ACCUMS FROM PARADISE TO ANJ /WEBCAMS
SHOW A COATING ATTM/...SO WATCH OUT FOR SOME SLICK AM TRAVEL IN
THESE SPOTS.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 420 AM EDT THU APR 4 2013
HIGH IMPACT WEATHER POTENTIAL: GALE FORCE WINDS OVER MUCH OF
NORTHERN LAKE MICHIGAN THROUGH MID MORNING. WILL LIKELY HAVE SOME
COASTAL WIND GUSTS ABOVE 30 MPH TODAY...OTHERWISE...NO HIGH
IMPACT WEATHER EXPECTED.
OVERVIEW: SURFACE MAP EARLY THIS MORNING REVEALS HIGH PRESSURE
RESPONSIBLE FOR THE BEAUTIFUL /ALBEIT CHILLY/ AFTERNOON YESTERDAY
HAVING PUSHED SOUTH AND EAST INTO THE OHIO VALLEY/MID ATLANTIC
REGION...THIS HAS ALLOWED BROAD SOUTHWESTERLY FLOW TO DEVELOP BETWEEN
THIS FEATURE AND RATHER IMPRESSIVE SURFACE LOW NOW TRAVELING FROM
WEST TO EAST ACROSS NORTHERN ONTARIO. PRIMARY FEATURE OF NOTE
THROUGH THE SHORT TERM PORTION OF THE FORECAST IS A COLD FRONT
DRAPED TO THE SOUTH AND WEST OF THIS LOW...APPROACHING LAKE SUPERIOR
AS OF THIS WRITING. STRENGTHENING SOUTHWESTERLY WINDS OVER NORTHERN
MICHIGAN HAVE PRECLUDED STEEP TEMPERATURE FALLS OVERNIGHT WITH MOST
LOCATIONS AT LEAST 10F WARMER THAN 24 HOURS AGO. LLEVEL MOISTURE
HAS NOT RESPONDED IN TANDEM...WITH 00Z APX RAOB SHOWING A PALTRY
0.14" PWAT. CLOSER TO THE FRONT...HOWEVER...PRECIPITATION ECHOES
HAVE BEEN BLOSSOMING OVER THE PAST COUPLE OF HOURS AS ROBUST LOW
LEVEL JET AT H8 /50KTS+/ TRANSPORTS A PLUME OF 2/3" PWATS RAPIDLY
EASTWARD.
THROUGH DAYBREAK: WINDS CONTINUE TO RAMP UP FROM WEST TO EAST...WITH
SLOWLY INCREASING MID AND UPPER LEVEL CLOUDINESS...PRIMARILY FROM THE
STRAITS NORTH. TIMING AREA OF INCREASING RADAR ECHOES SUGGESTS
PRECIPITATION COULD ARRIVE AS EARLY AS 5-6AM OVER EASTERN UPPER AS
SOME SNOW SHOWERS. INTERESTING TO NOTE SURFACE DEWPOINT TREND OVER
THE PAST FEW HOURS OVER NORTHERN LOWER...WITH VALUES PLUMMETING TO
BELOW 10F AT TVC/CAD AND ROPPING EVERYWHERE AWAY FROM LAKE
MICHIGAN. THIS SUGGESTS THE SLOWING TREND IN FRONTAL PRECIP
ARRIVAL /SEEN IN RECENT RENDTIONS OF THE HRRR/RAP/ ARE LIKELY ON
THE RIGHT TRACK.
TODAY: COLD FRONT PUSHES THROUGH NORTHERN MICHIGAN TODAY...STARTING
THE DAY OVER WESTERN UPPER AND REACHING MY SOUTHEASTERN ZONES BY
EVENING. PRIMARY CONCERNS TODAY CENTER AROUND PRECIPITATION
CHANCES AS THIS BOUNDARY MOVES THROUGH...AS WELL AS THE STRENGTH
OF SOUTHWESTERLY WINDS AHEAD OF IT.
TRAJECTORY ANALYSIS SHOWS LLEVEL SOURCE REGION FOR AIR OVER NORTHERN
LOWER TODAY COMES FROM THE IOWA/ILLINOIS REGION 24 HOURS AGO...AN
AREA FEATURING A DEARTH OF LLEVEL MOISTURE. SO...BOUNDARY WILL BE
FIGHTING INCREASINGLY DRY ATMOSPHERE AS IT PUSHES SOUTH AND EAST
WITH LLEVEL MOISTURE TONGUE THINNING. LLEVEL CONVERGENCE IS
MODEST...BUT WILL HAVE SOME HELP FROM AN ARRIVING JET MAX /AND ITS
ASSOCIATED RIGHT ENTRANCE REGION/ AS WELL AS CONTINUED ISENTROPIC
ASCENT. NET RESULT: EXPECT A BROKEN LINE OF SHOWERS TO SINK SOUTH
DURING THE DAY...WEAKENING AS THEY DO SO. RECENT MODEL TRENDS HAVE
CONTINUED TO SLOW THE SOUTHWARD MOVEMENT OF ANY PRECIPITATION...
AND WHILE THIS FORECAST REPRESENTS A SLOWING TREND...IT COULD
REQUIRE FURTHER SLOWING WITH PRECIITATION POTENTIALLY COMPLETELY
FALLING APART BEFORE MAKING IT MUCH SOUTH OF M-32.
PTYPE: STARTS THE DAY ALL SNOW...BUT RAPIDLY WARMING SURFACE LAYER
SUGGESTS PREDOMINATE TYPE TO SWITCH TO RAIN COASTAL LOCALES BY LATE
MORNING AND ALL AREAS BY AFTERNOON. ONLY CAVEAT TO THIS WILL BE
OVER THE INTERIOR HIGH SPOTS WHERE WET BULBS IN THE MID 30S INDICATE
A FEW SNOWFLAKES MIGHT MIX IN AT ANY TIME...ESP IF PRECIPITATION
RATES ARE DECENT. OVERALL VERY LITTLE IMPACT EXPECTED...HOWEVER...
OUTSIDE OF A FEW SLICK SPOTS TO START THE DAY FROM THE BRIDGE
NORTH. PAVEMENT TEMPS WILL BE TOO WARM TO SUPPORT ANY ICING BY MID
MORNING OVER NORTHERN LOWER.
WINDS: PRETTY MUCH FULLY FORCED BY THE STRENGTH OF THE LOW LEVEL
JET /40-50KTS AT H9 EARLY...WEAKENING AS IT HEADS SOUTH/ AND THE
AMOUNT OF MIXING WE CAN DEVELOP AHEAD OF THE BOUNDARY. GIVEN A
SOMEWHAT SLOWER ARRIVAL TO THE BOUNDARY...MIXING HEIGHTS SHOULD GET
A CHANCE TO BUILD EARLY...WITH MOMENTUM TRANSPORT SUGGESTING WE CAN
LIKELY TAP 30KTS. SO...EXPECT SOUTHWEST WINDS 15-25 MPH WITH GUSTS
OVER 30 MPH BY LATE MORNING AND THROUGH THE AFTERNOON OVER
NORTHERN LOWER...A LITTLE WEAKER THAN THIS FURTHER NORTH.
TEMPS: T9 ROCKETS TO JUST ABOVE FREEZING AHEAD OF THE BOUNDARY...
WITH THE POTENTIAL TO PRODUCE LOW-MID 50S AHEAD OF THE BOUNDARY.
COMPLICATING THIS WILL BE CLOUDS AND PRECIP...WHICH...WITH PRETTY
SUBSTANTIAL LLEVEL DEWPOINT DEPRESSIONS SUGGESTS AMPLE OPPORTUNITY
FOR EVAPORATIONAL COOLING. WILL ALLOW SOUTHEASTERN ZONES TO MAKE A
RUN AT 55...WITH LOCALES NORTH OF THIS GENERALLY IN THE MID-UPPER
40S.
TONIGHT: NORTHWEST WINDS WILL USHER COLDER AIR INTO THE REGION AS
HIGH PRESSURE BUILDS IN FROM THE NORTHERN PLAINS. T8 FALLS TO -12C
SOUTH/-15C NORTH AFTER MIDNIGHT...WHICH WITH A MINOR AMOUNT OF
RESIDUAL 850-700MB MOISTURE SUGGESTS THAT SOME LAKE RESPONSE MAY TRY
AND GET GOING...BUT NOT UNTIL THE VERY END OF THIS PERIOD. WILL
CARRY CHANCE POPS AFTER 09Z BUT NO SIGNIFICANT SNOWFALL EXPECTED.
TEMPERATURES LOOK TO FALL INTO THE MID 20S AS COLD AIR ADVECTION IS
OFFSET SOMEWHAT BY RESIDUAL WINDS AND SOME LAKE CLOUDINESS /NORTH/.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 420 AM EDT THU APR 4 2013
FRIDAY...INITIALLY, THERE WILL BE SOME LIGHT SNOW AND FLURRIES IN E
UPPER, MAINLY NEAR WHITEFISH POINT AS THE 850 MB TEMPERATURES FALL
TO AROUND -14C WITH ABOUT 50% RH IN THE 850-700 MB LAYER. THIS WILL
BE MAINLY IN THE MORNING, BECAUSE AS THE HIGH PRESSURE BUILDS INTO
THE REGION MORE DRY AIR PUSHES INTO THE FORECAST AREA, AND THE 850
MB TEMPERATURES RISE ABOVE -12C BY 18Z. SO WILL GO WITH A DRY DAY
OVERALL.
FRIDAY NIGHT...THE WARM ADVECTION WING FROM THE NEXT SYSTEM BEGINS
TO MOVE INTO THE REGION, ESPECIALLY AFTER 06Z. THIS WILL BRING A
CHANCE OF SNOW BY 12Z IN THE WESTERN PART OF THE FORECAST AREA. THE
LOWER LEVEL MOISTURE WILL BE THE MAIN CONCERN AS THE POPS ARE DRAWN
ROUGHLY WHERE THE 850 MB MOISTURE IS ABOVE 50%. HOWEVER, THIS COULD
JUST AS EASILY BE NOTHING UNTIL THE DAY ON SATURDAY, IF THE ATMOSPHERE
DOESN`T SATURATE FAST ENOUGH.
SATURDAY...THE WARM FRONT MOVES NORTH A BIT, BUT FOR THE MOISTURE
PART ONCE IT GETS TO AROUND THE STRAITS, IT LOOKS LIKE IT TRAVELS
EAST, WITH THE SFC LOW FOLLOWING ALONG IT. THIS SETS UP SNOW IN E
UPPER, WHICH COULD HAVE LIGHT TO MODERATE AMOUNTS THROUGH THE DAY.
WOULD EXPECT A MIX, ESPECIALLY BETWEEN M-32 AND THE STRAITS AS THE
PROFILES ARE EITHER ON THE 0C LINE. SOUTH OF M-32, THINK THAT IT
WILL BE MAINLY RAIN. OVERNIGHT, THE WARMER AIR WITH BOTH MODELS,
GETS TO THE STRAITS, THE RAIN WILL LIKELY GET ALL THE WAY TO THE
STRAITS, AND WE`LL GET A MIX IN E UPPER. THE CONCERN, BASED ON THE
PROFILES OF BOTH MODELS, IS THAT WE WILL PARTIALLY MELT SOME OF
THE SNOW (TEMPERATURES IN THE PROFILE GET TO +2C AROUND 850 MB
THEN FALL TO OR BELOW 0C IN E UPPER). SO WILL GO WITH SNOW/RAIN OR
FREEZING RAIN MIX AT THIS POINT, AND KEEP IT MENTIONED IN HWOAPX.
THE COLD AIR MOVES INTO E UPPER AGAIN ONCE THE LOW MOVES EAST. SO
E UPPER WILL SEE A CHANGE OVER AGAIN BETWEEN 06Z AND 12Z.
EXTENDED (SUNDAY THROUGH WEDNESDAY)...SUNDAY, THE MODELS MOVE THE
LOW EAST OF THE REGION AND THE COLD AIR MOVES BACK. HOWEVER, THINGS
ARE DRY ENOUGH AND WARM ENOUGH, THAT LITTLE IF NO PRECIPITATION WILL
FALL. MONDAY, LOOKS LIKE ANOTHER WAVE FORMS ON THE FRONT THAT
STALLS IT, AND EVEN ALLOWS FOR SOME WARMING. SO WILL GO WITH
CHANCE OF RAIN IN N LOWER AND A MIX IN E UPPER. TUESDAY, THE LOW
NO LONGER MOVES OUT OF THE MID MISSISSIPPI VALLEY AS THE MODELS
FOCUS DEVELOPMENT ON THE CLOSED 500 MB LOW IN THE SOUTHWEST
STATES. THIS WOULD KEEP THE SFC LOW IN TX/OK REGION WITH A WARM
FRONT/SFC TROUGH THAT IS STALLED IN THE OHIO VALLEY. OVERNIGHT,
THE GFS BEGINS TO LIFT THE 500 MB LOW INTO THE NORTHERN BRANCH.
THE ECMWF LOOKS BETTER WITH THE SLOWER LIFTING OF THE WAVE KEEPING
THE RAIN AND THE WARM FRONT ALONG OR SOUTH OF THE OHIO VALLEY.
WEDNESDAY, THINKING THAT THE GFS IS TOO WET, DUE TO THE PHASING OF
THE SYSTEMS. WOULD BE MORE INCLINED TO GO WITH THE ECMWF IDEA WITH
THE HIGH SETTLING IN OVER THE GREAT LAKES. WHICH WOULD KEEP US
DRY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 132 AM EDT THU APR 4 2013
SUMMARY: A COLD FRONT WILL PUSH SOUTHEAST THROUGH THE GREAT LAKES
REGION TODAY...BRINGING A BAND OF SCATTERED RAIN AND SNOW SHOWERS
ALONG WITH GUSTY SOUTHWEST WINDS. SKIES WILL PARTIALLY CLEAR BEHIND
THE FRONT THIS EVENING AS HIGH PRESSURE BUILDS TOWARDS THE GREAT
LAKES FROM CENTRAL CANADA.
RESTRICTIONS: REALLY NOT THAT EXCITED ABOUT RESTRICTION POTENTIAL
WITH THIS BOUNDARY AS LLEVEL AIRMASS IS QUITE DRY. INHERITED TAFS
INCLUDED PERIOD OF MVFR AT PLN AND THIS LOOKS LIKE A GOOD WAY TO GO
WITH THE LLEVEL MOISTURE GRADUALLY ERODING AS THE BOUNDARY HEADS
SOUTH. THUS...AT APN/TVC/MBL EXPECT A VFR TAF PERIOD WITH A CHANCE
OF AN AFTERNOON RAIN SHOWER. AT PLN...CHANCES FOR A SHOWER /RAIN OR
SNOW/ ARE MORE LIKELY AND WILL CONTINUE BRIEF PERIOD OF MVFR. VFR
CONDITIONS /RESIDUAL 4KFT CLOUD DECK/ TAKE OVER BEHIND THE FRONT
THIS EVENING.
WINDS: LIGHT WINDS WILL BECOME SOUTHWESTERLY 5-10KTS TOWARDS
DAYBREAK BEFORE INCREASING MARKEDLY TO 15G25KTS FOR THE LATE
MORNING/EARLY AFTERNOON. BEYOND THIS...WINDS WILL SHIFT
NORTHWESTERLY AND DIMINISH TO AROUND 10KTS THIS EVENING.
LLWS: IMPRESSIVE LOW LEVEL JET AHEAD OF ARRIVING FRONT WILL ALLOW
FOR THE DEVELOPMENT OF LLWS LATER TONIGHT AT ALL SITES WITH 1.5KFT
WINDS INCREASING TO 40 KTS FROM THE SOUTHWEST. WIND SHEAR WILL
ABATE DURING THE MORNING HOURS AS MIXING COMMENCES.
&&
.MARINE...
ISSUED AT 420 AM EDT THU APR 4 2013
SUMMARY: A COLD FRONT WILL PUSH THROUGH NORTHERN MICHIGAN TODAY WITH
GUSTY SOUTHWEST WINDS AHEAD OF IT SHIFTING NORTHWESTERLY BEHIND IT
THIS EVENING AS HIGH PRESSURE BUILDS INTO THE GREAT LAKES REGION.
HIGH PRESSURE WILL REMAIN IN CONTROL OF OUR WEATHER THROUGH FRIDAY
NIGHT.
HEADLINES: GALE WARNING THROUGH LATE MORNING STILL LOOKS GOOD OVER
PORTIONS OF NORTHERN LAKE MICHIGAN. ELSEWHERE...WILL EXPAND SMALL
CRAFTS TO ALL ZONES FOR TODAY GIVEN ROBUST WIND FIELD AHEAD OF
APPROACHING COLD FRONT. MARGINAL SMALL CRAFT CONDITIONS CONTINUE
THROUGH TONIGHT BEFORE A BREAK IN WIND/WAVE ACTIVITY IS EXPECTED
FRIDAY. NEXT STORM SYSTEM ARRIVES SATURDAY WITH A RENEWED PERIOD OF
SMALL CRAFTS LIKELY THROUGHOUT THE NEARSHORE WATERS OF NORTHERN
MICHIGAN.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR
LHZ345>349.
LM...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR LMZ323-
345-346.
GALE WARNING UNTIL 11 AM EDT THIS MORNING FOR LMZ341-342-344.
LS...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR LSZ321-
322.
&&
$$
UPDATE...ARNOTT
SYNOPSIS...JL
SHORT TERM...ARNOTT
LONG TERM...JL
AVIATION...ARNOTT
MARINE...ARNOTT
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
620 AM EDT THU APR 4 2013
.SYNOPSIS...
LOW PRESSURE PASSES SOUTH LATE TODAY AND TONIGHT WITH THE CHANCE FOR
RAIN. MODERATING TEMPERATURES OVER THE WEEKEND. FRONT NEARBY SUNDAY
INTO NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
615 AM UPDATE...
NO CHANGES ATTM.
PREVIOUS DISCUSSION BELOW...
MDLS COMING IN A BIT FASTER WITH ONSET OF PCPN LATER TDY AS SFC
LOW ORGANIZES ALONG GA/SC COAST. HOWEVER VERY DRY LLVLS WILL BE
BATTLING MOISTURE ADVECTION FROM S. AS SUCH DID NOT GO AS FAST AS
MDLS SUGGEST ONCE INTO S WV PLATEAU. LATEST RAP MDL SEEMS TO HAVE
A BETTER REFLECTION OF CURRENT THINKING AND USED IT AS A GUIDE
THRU 00Z. DO BRING IN HIGH POPS ACROSS SW VA BY 18Z AND THEN
SLOWLY SPREAD N UP THE EASTERN SLOPES TO INCLUDE MUCH OF
POCAHONTAS CO WITH THE CATEGORICAL POPS. HAVE A SHARP GRADIENT
HEADING W...WITH CHC POPS EXTENDING TO CRW- HTS AREA AND UP TOWARD
CKB. FEEL SE OH AND NW LOWLAND CO STAY DRY. HAVE ARND A THIRD OF
AN INCH QPF FOR SW VA AND UP THE EASTERN SLOPES. QUICKLY TAILS OF
W OF I79 CORRIDOR. EXIT BULK OF PCPN BY 06Z TO THE E...WITH
LINGERING CHC POPS FOR S/W TROF AXIS SLIDING THRU.
THERE IS SOME CONCERN FOR WINTRY PCPN AT THE ONSET ACROSS RIDGES
IN POCAHONTAS CO. MDLS INDICATE GOOD WET BULBING ARND 00Z TO
REFLECT SOME WET SN OR MIX POTENTIAL BEFORE SWITCHING TO RA LATER
IN EVE. USED SFC AND MODEL ALOFT TOO TO REFLECT THIS IN WX GRIDS.
WILL KEEP ACCUMULATIONS OUT OF GRIDS FOR NOW THOUGH.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
MODELS IN GOOD AGREEMENT SHOWING SYSTEM PULLING OFF TO THE EAST
EARLY FRIDAY...WITH DRY WEATHER EXPECTED BY MIDDAY. WILL SPEED UP
THE EXODUS OF THE POPS. MOS GUIDANCE FOR HIGHS ON FRIDAY HAS BEEN
TRENDING DOWNWARD...BUT STILL LOOKS TOO HIGH. HAVE UNDERCUT MOS ONCE
AGAIN FOR HIGHS FRIDAY...AND ALSO ON SATURDAY.
A COLD FRONT THEN PUSHES INTO THE AREA ON SUNDAY...BEFORE STALLING
OVER THE AREA. SOME DEBATE AMONG THE MODELS ON WHERE THE FRONT WILL
STALL. CURRENT FORECAST LOOKS LIKE A GOOD COMPROMISE FOR NOW...SO
DID NOT CHANGE WITH THE EXCEPTION OF SLOWING THE ARRIVAL OF THE
SHOWERS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
WAVY FRONT APPROACHES THIS WEEKEND AND THEN HANGS NEARBY THE
BALANCE OF THE PERIOD. RIDGING ADVERTISED FOR EARLY NEXT WEEK OVER
THE PAST FEW DAYS IS ALL BUT GONE...THE GFS STILL AMPLIFYING ONE BUT
ALONG THE E COAST TUE. THAT IS WHEN THE ECMWF IS MARKEDLY DIFFERENT
WITH THE NORTHERN STREAM OVER CANADA...USING EASTERN CANADIAN
TROUGHING TO SINK THE CONFLUENCE...AND FRONTAL ZONE...SWD. THIS
WOULD MAKE THE LATTER PORTION OF THE FCST MUCH WETTER AND COOLER
THAN CURRENTLY CODED. AS PER HPC...IT AND TELECONNECTIONS DEPENDENT
UPON SW CONUS TROUGH WILL PLAY A ROLE IN HOW FAR N THE FRONT IS OVER
THE EASTERN CONUS DAYS 6-7.
DRY WEATHER GIVES WAY TO INCREASING CHANCE FOR SHOWERS NW TO SE DAY
3 NT AND DAY 4 WITH INITIAL APPROACH OF FRONT AND INITIAL UPPER
LEVEL WAVE. KEEP CHANCE THROUGH THE BALANCE OF THE FCST...HIGHEST N
AND NW...LOWEST S AND SE...HAVE HAVE JUST SLIGHT CHANCE EARLY ON.
MORE OR LESS EQUAL CHANCE FOR PRECIPITATION THROUGHOUT THE AREA DAY
7. ALSO INTRODUCED SLIGHT CHANCE FOR THUNDER DURING THE AFTERNOONS
AND EARLY EVENINGS BEGINNING MON AS DEW POINTS INCREASE TO NEAR 50.
BLENDED IN ADJMEXBC FOR HIGHS EARLY ON AND THEN HPC DAYS 6 AND 7
HIGHS AND ALL LOWS. ADJMEXBC APPEARED TOO LOW ON LOWS GIVEN SW
FLOW...RISING DEW POINTS AND CLOUDS.
&&
.AVIATION /10Z THURSDAY THROUGH MONDAY/...
12Z THURSDAY TO 12Z FRIDAY...
LIGHT SURFACE WINDS BECOMING GUSTY AGAIN AFTER 15Z...MAINLY
ACROSS THE HIGHER TERRAIN. A LOW PRESSURE SYSTEM WILL APPROACH
FROM THE SOUTH LATE TDY...ALLOWING RA TO OVERSPREAD SW VA BY 18Z
AND SLOWLY SPREADING N UP THE WV MTNS. THIS WILL CREATE GENERAL MVFR
CONDITIONS ACROSS SOUTHWEST VA 18Z...SOUTHERN WV BY 00Z... AND UP
WV MTNS BY 03Z. KEPT SOUTHEAST OHIO AND NORTHERN WV REMAINING VFR
IN MID DECK. KHTS AND KCRW TRICKY AS THEY WILL BE ON THE NW FRINGE
OF BEST LLVL MOISTURE AND PCPN. WILL KEEP THEM VFR WITH THIS
ISSUANCE BUT ALLOW CIGS TO LWR INTO LOW END VFR.
THERE MAY BE SOME FG OVERNIGHT FOR AREAS THAT RECEIVE RA AS THE LLVL
FLOW REMAINS ON THE LIGHT SIDE. HOWEVER CONFIDENCE IS NOT
PARTICULARLY HIGH TO INCLUDE IN TAFS ATTM.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z FRIDAY...
FORECAST CONFIDENCE...MEDIUM.
ALTERNATE SCENARIOS: LOW PRESSURE SYSTEM MAY SPREAD MOISTURE AND
LOW CIGS FARTHER NORTH THAN CURRENTLY FORECAST TOWARDS THE END OF
THE TAF PERIOD. FG MAY DEVELOP OVERNIGHT ACROSS AREAS THAT RECEIVE RA.
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.
UTC 1HRLY 11 12 13 14 15 16 17 18 19 20 21 22
EDT 1HRLY 07 08 09 10 11 12 13 14 15 16 17 18
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z FRIDAY...
NO WIDESPREAD IFR CONDITIONS EXPECTED.
&&
.FIRE WEATHER...
RH VALUES WILL AGAIN DIP INTO TEENS AND 20S PERCENT WISE AS DWPTS
MIX DOWN INTO THE TEENS AND TEMPS CLIMB. MOISTURE ADV FROM S IN
AFTN SHOULD ALLOW RH TO RECOVER UP TO CENTRAL WV WITH RA ACROSS SW
VA. HOWEVER...ACROSS PORTIONS OF NE KY...SE OH AND N WV...THE DRY
AIR WILL PREVAIL TDY. SOME AFTN GUSTS ARND 15 KTS MAY ALSO BE
EXPECTED ACROSS N WV. WITH VERY DRY 10 HR FUELS IN PLACE...AN
ENHANCED FIRE DANGER THREAT MAY BE REALIZED TODAY. CONDITIONS
WILL BE MONITORED AND COORDINATED WITH THE APPROPRIATE STATE
FORESTRY PERSONNEL FOR THE POTENTIAL FOR ANY FIRE WEATHER
STATEMENTS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/RPY/30
NEAR TERM...30
SHORT TERM...RPY
LONG TERM...TRM
AVIATION...30
FIRE WEATHER...30
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
955 AM CDT THU APR 4 2013
.UPDATE...
AN UPPER LEVEL LOW PRESSURE SYSTEM CURRENTLY LOCATED OVER THE
ARKLATEX REGION WILL TRACK EAST ACROSS NORTH CENTRAL MISSISSIPPI
TODAY. LOOKING AT THE LATEST HRRR MODEL...BEST RAIN CHANCES WILL
OCCUR FROM EASTERN ARKANSAS TO NORTHWEST TENNESSEE. HAVE ADJUSTED
POPS ACCORDINGLY. HAVE ALSO LOWERED HIGHS SLIGHTLY. EXPECT
TEMPERATURES TO REMAIN IN THE UPPER 40S FOR HIGHS FOR THE MOST
PART DUE TO THE CLOUDS AND RAIN. UPDATE WILL BE OUT SHORTLY.
KRM
&&
.DISCUSSION... /ISSUED 308 AM CDT THU APR 4 2013/
SKIES WERE CLOUDY ACROSS THE MIDSOUTH WITH A FEW AREAS OF LIGHT
RAIN ON RADAR. WINDS WERE NORTHEAST AROUND 5 MPH WITH TEMPERATURES
HOLDING IN THE MID AND UPPER 40S. ON SATELLITE AN UPPER LEVEL LOW
WAS CENTERED IN SOUTHWEST OKLAHOMA WITH LEADING EDGE OF ASSOCIATED
ENHANCED CLOUD COVER AND PRECIPITATION ENTERING WESTERN ARKANSAS.
FOR TODAY AND TONIGHT...ONE LAST DREARY DAY FOR THE MIDSOUTH IN
REGARDS TO RAIN AND UNSEASONABLY COLD TEMPERATURES. FORTUNATELY
THE MODELS SHOW THE AFOREMENTIONED LOW BECOMING AN OPEN WAVE...AND
BEGINNING TO FILL AS IT PASSES JUST TO OUR SOUTH THIS
EVENING. THUS...RAINFALL AMOUNTS WILL LIKELY REMAIN UNDER A
QUARTER OF AN INCH FOR MANY MIDSOUTHERNERS. TEMPERATURES WILL
STRUGGLE TO REACH 50F ACROSS THE NORTH AND MID 50S SOUTH. AS THE
LOW TRACKS INTO ALABAMA AND GEORGIA TONIGHT AN UPPER LEVEL RIDGE
OVER THE PLAINS WILL QUICKLY BUILD INTO THE AREA. THIS SHOULD IN TURN
ALLOW FOR FASTER CLEARING EARLY FRIDAY MORNING. WITH DRIER AIR
WILL PUSHING IN FROM MISSOURI TEMPERATURES WILL EASILY CLIMB INTO
THE MID 60S.
THE REAL START TO THE MIDSOUTH WARMING TREND HOWEVER WILL BEGIN ON
SATURDAY AS LOW LEVEL WINDS TURN SOUTHERLY. SKIES THOUGH...MAY
BECOME PARTLY SUNNY THROUGHOUT THE DAY AS MODEL CROSS SECTIONS
YIELD THICKENING CIRRUS CLOUDS EXTENDING WELL EAST OF THE ROCKIES.
TEMPERATURES SHOULD STILL MANAGE TO MAKE IT INTO THE LOW AND MID 70S.
GULF MOISTURE WILL BEGIN TO SURGE NORTHWARD SATURDAY NIGHT AND SUNDAY
AS A COLD FRONT BECOMES STALLED ACROSS THE CORN BELT AND CENTRAL
PLAINS. WAA WILL CONTINUE ON SUNDAY DEVELOPING A DEEP LAYER CAP
BETWEEN 850 AND 700MB. THUS ANY ISOLATED CONVECTION FORMING WEST
OF THE MISSISSIPPI RIVER WILL EITHER WAA SHOWERS OR ELEVATED THUNDER.
HIGHS ON SUNDAY WILL REMAIN IN THE 70S WITH MILDER LOWS IN THE
MID AND UPPER 50S.
MONDAY THROUGH WEDNESDAY NIGHT...THIS PERIOD WILL SEE AN INCREASE
THREAT FOR STORMS AND SEVERE WEATHER AS A NEW STORM DEEPENS OVER
THE CENTRAL ROCKIES. THE UPPER FLOW OVER THE MIDSOUTH WILL BACK
FROM THE SOUTHWEST WITH SPEEDS INCREASING. THE COMBINATION OF
MINOR WAVES IN THE FLOW RIDING OVER THE STALLED BOUNDARY TO OUR
NORTH AND DEWPOINTS INCREASING TO THE MID AND UPPER 60S...WILL
WEAKEN THE ESTABLISHED CAP ALLOWING FOR SFC BASED CONVECTION. THE
GFS AND EURO BOTH SPORT 1500+ J/KG OF CAPE...7.0C+ LAPSE
RATES...AND LIFTED INDICES OF NEAR -6C. THE GFS ALSO IS INDICATING
0-1KM HELICITY VALUES IN EXCESS OF 3.0 M^2/S^2 INDICATING ROTATING
STORMS. SINCE MODEL RUNS OVER THE PAST THREE DAYS HAVE BEEN
CONSISTENT IN THE THREAT FOR SEVERE WEATHER FOR TUESDAY...WILL
INTRODUCE THIS THREAT IN THE UPCOMING HWO.
DEPENDENT ON AMOUNT OF CUMULUS CLOUD COVER/CONVECTION...DAYTIME
HIGHS COULD WARM CLOSE TO 80F. SOUTH WINDS WILL ALSO INCREASE AND
GUST TO 30MPH ON TUESDAY AS A SURFACE WAVE DEEPENS IN WEST TEXAS.
THIS FEATURE IS PROGGED TO MOVE INTO THE OZARKS ON WEDNESDAY AND
MAY PROVIDE A SECOND DAY THREAT FOR SEVERE WEATHER OVER OUR AREA.
JAB
&&
.AVIATION...
12Z TAF CYCLE (04/12Z-05/12Z)
SURFACE LOW PRESSURE WILL MOVE ALONG THE NORTHEASTERN GULF COAST
WHILE AN UPPER LEVEL TROUGH MOVES OVER THE MIDSOUTH TODAY. THIS WILL
CAUSE RAIN ACROSS THE MIDSOUTH. FOR TODAY...THINK IFR CONDITIONS
WILL PREDOMINATE AT KMEM...KMKL...AND KTUP WITH MVFR CONDITIONS AT
KJBR. CONDITIONS THIS EVENING GRADUALLY IMPROVING TO VFR AT
KMEM...KMKL...AND KJBR AS THE LOW PRESSURE SYSTEM MOVES EASTWARD
AND THE RAIN ENDS. KTUP IS EXPECTED TO IMPROVE TO MVFR AROUND
05/06Z.
WINDS TODAY NE 7-10 KTS. WINDS TONIGHT NORTHERLY 3-8 KTS.
JCL
&&
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 48 42 66 49 / 80 40 0 0
MKL 48 39 65 43 / 80 50 0 0
JBR 49 39 66 44 / 80 30 0 0
TUP 49 43 65 43 / 60 50 10 0
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
334 PM CDT THU APR 4 2013
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 306 PM CDT THU APR 4 2013
LIGHT SURFACE PRESSURE GRADIENT IS EVIDENT IN 20Z RAP ANALYSIS. THIS
LIGHT PRESSURE GRADIENT IS RESPONSIBLE FOR LIGHT WINDS WHICH ARE
EVIDENT IN SURFACE OBSERVATIONS ACROSS THE FORECAST AREA THIS
AFTERNOON. EXPECT THESE LIGHT WINDS TO EVENTUALLY SHIFT TO THE SOUTH
OVERNIGHT TONIGHT AS A SURFACE LOW COMES INTO FORMATION OVER THE
HIGH PLAINS. SOUTHERLY WINDS WILL INCREASE THROUGH THE DAY ON FRIDAY
TO AROUND 20 TO 25 MPH...WITH GUSTS TO AROUND 30 MPH. DEEP MIXING
WILL CAUSE ALLOW FOR LOW LEVEL WINDS AROUND 850 MB TO COME TO THE
SURFACE...WHICH MAY BRING WARMER/DRYER CONDITIONS AND STRONGER WIND
GUSTS. THIS WILL HAVE FIRE WEATHER IMPLICATIONS...WHICH ARE
DISCUSSED IN THE FIRE WEATHER DISCUSSION BELOW. AT THIS TIME EXPECT
VERY HIGH FIRE DANGER FOR MOST OF THE AREA THROUGH THE DAY ON
FRIDAY.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 306 PM CDT THU APR 4 2013
FRIDAY NIGHT THROUGH SUNDAY...FRIDAY NIGHT LEE SIDE LOW PRESSURE
DEEPENS OVER THE HIGH PLAINS INCREASING THE PRESSURE GRADIENT
ACROSS THE AREA. THEREFORE THE WINDS WILL CONTINUE TO BE GUSTY
THROUGH THE OVERNIGHT HOURS ESPECIALLY ACROSS EASTERN KANSAS. THIS
WILL KEEP LOW TEMPERATURES FRIDAY NIGHT IN THE LOW 50S. A
SOUTHWESTERLY LOW LEVEL JET INCREASES FRIDAY NIGHT BRINGING
LIMITED MOISTURE TO THE REGION. MEANWHILE A SHORTWAVE ADVANCES
EASTWARD INTO NEBRASKA AND EVENTUALLY IOWA ON SATURDAY. IT APPEARS
THAT THE STRONGER LIFT ASSOCIATED WITH THE WAVE WILL BE NORTH OF
THE AREA FRIDAY NIGHT AND SATURDAY MORNING. THERE IS SLIGHT CHANCE
OF SOME WEAK LIFT EXTENDING SOUTH INTO KANSAS SO COULD NOT RULE
OUT AN ISOLATED SHOWER FRIDAY NIGHT. A WEAK COLD FRONT ASSOCIATED
WITH THE WAVE WILL PUSH SOUTHWARD THROUGH THE AREA DURING THE DAY
ON SATURDAY SHIFTING THE WINDS TO THE NORTH. THE FRONT WILL
RETREAT BACK TO THE NORTH ON SUNDAY AND SETS UP SOMEWHERE IN
NORTHEAST KANSAS. A WEAK SHORTWAVE EMBEDDED IN THE ZONAL MID LEVEL
FLOW PROGRESSES EASTWARD ACROSS KANSAS DURING THE DAY PROVIDING
LAGER SCALE LIFT. SOUTHERLY LOW LEVEL FLOW WILL INCREASE THE
MOISTURE RETURN ACROSS THE AREA AS ML CAPE VALUES APPROACH 500
J/KG AIDING IN THUNDERSTORM DEVELOPMENT. MID LEVEL FLOW ALSO
INCREASES SUNDAY WITH 0-6 KM BULK SHEAR VALUES AROUND 40 KTS WHICH
SUPPORTS THE CHANCE OF STRONGER ORGANIZED THUNDERSTORMS SUNDAY
AFTERNOON AND OVERNIGHT.
EXTENDED FORECAST (SUN NIGHT-THURS)...AN ACTIVE PATTERN SETTING UP
THROUGH THIS PERIOD...AND SEVERE WEATHER APPEARS INCREASINGLY
LIKELY....HOWEVER TIMING AND PLACEMENT REMAINS SOMEWHAT
UNCERTAIN. SUNDAY NIGHT THE GFS AND A SOMEWHAT FASTER EC BRING A
SHORTWAVE OVER THE WARMFRONT PROGGED E/W OVER OUR AREA...WITH THE
EC HOLDING THE FRONT FARTHER SOUTH THAN THE GFS. ENOUGH CAPE AND
SHEAR PRESENT THAT SOME OF THE STORMS OVERNIGHT COULD BRING HAIL.
THE ENSUING WEATHER FOR MONDAY WILL BE DEPENDENT ON HOW FAR NORTH
THE WARMFRONT LIFTS DURING THE DAY. EC AND GFS BOTH BREAK OUT
CONVECTION NEAR THE BOUNDARY AND LESS SO IN THE WARM SECTOR MONDAY
EVENING THROUGH THE MORNING HOURS ON TUESDAY. SEVERE WEATHER
POTENTIAL CONTINUES TO INCREASE INTO TUESDAY AND TUESDAY
AFTERNOON AS WESTERN TROF APPROACHES...AND SHEAR AND INSTABILITY
ALSO INCREASE AND MOVE NORTH ACROSS THE CWA WITH THE WARM SECTOR.
DIFFERENCES INCREASE BEYOND TUESDAY AS GFS MOVES THE COLDFRONT
THROUGH QUICKLY WITH EC DROPPING A CLOSED UPPER LOW ACROSS EASTERN
KANSAS AND THE FRONT MOVING THROUGH WEDNESDAY EVENING. WHILE
WED/THURS WILL BRING A COOL END OF THE WEEK...MUCH UNCERTAINTY
WITH PRECIP AMOUNTS AND TYPES. 67
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1217 PM CDT THU APR 4 2013
EXPECT VFR CONDITIONS THROUGH FORECAST PERIOD WITH INCREASING
SOUTHERLY WINDS FRIDAY MORNING/AFTERNOON 15 TO 25 MPH GUSTING TO
30 MPH.
JL
&&
.FIRE WEATHER...
ISSUED AT 242 PM CDT THU APR 4 2013
WINDS ON FRIDAY WILL CHANGE FROM WNW OVERNIGHT TO THE SOUTH BY
EARLY FRIDAY MORNING. BY FRIDAY AFTERNOON A STRONG SURFACE
PRESSURE GRADIENT WILL FORM A CROSS CENTRAL AND EASTERN KANSAS
CAUSING THE SOUTHERLY WINDS TO INCREASE TO AROUND 20 TO 25 MPH.
DEEP MIXING TO AROUND 3000 FEET WILL ALLOW FOR SOME 30 TO 35 MPH
WINDS TO REACH THE SURFACE AS WIND GUSTS LATER IN THE AFTERNOON
ON FRIDAY. AT THIS TIME IT LOOKS AS THOUGH DEWPOINTS IN THE LOWER
40S WILL PUSH NORTHWARD INTO THE AREA. THIS WILL KEEP RH VALUES IN
THE 30 TO 40 PERCENT RANGE...HOWEVER SHOULD DEEPER MIXING OCCUR
THE DEWPOINTS COULD GO A BIT LOWER THAN CURRENTLY FORECAST...WHICH
WOULD CAUSE RH VALUES TO DIP CLOSER TO 30 PERCENT. SINCE THE RH
VALUES SHOULD REMAIN ABOVE 30 PERCENT WILL NOT ISSUE ANY KIND OF
FIRE WEATHER HEADLINE...BUT STAY TUNED TO FORECAST UPDATES THROUGH
THE DAY ON FRIDAY FOR MORE INFORMATION.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...LEIGHTON
MID RANGE...SANDERS
LONG TERM...67
AVIATION...LEIGHTON
FIRE WEATHER...LEIGHTON
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1127 AM CDT THU APR 4 2013
.UPDATE...
UPDATED AVIATION SECTION FOR 18Z TAFS
ISSUED AT 928 AM CDT THU APR 4 2013
UPDATED THE GRIDS TO BETTER REFLECT ONGOING TRENDS. FARTHER SOUTH
SHIFT IN THE MODELS LAST 24 HOURS WORKING OUT OK. ESSENTIALLY WILL
BE A SHARP CUT OFF LINE FROM LIGHT RAINS AND SPRINKLES TO DRY
CONDITIONS. TRIED TO BETTER REFLECT THIS IN THE POP GRIDS. NOT SURE
HOW FAR NORTH THE LIGHT RAINS WILL BE ABLE TO MAKE IT. RAP MODELS
SUGGESTS NOT MUCH FARTHER. GIVEN THE VERY DRY AIR SEEN ON 12 UPA
DATA AT H9 AND H8...THAT APPEARS REASONABLE...ALTHOUGH WILL HEDGE
JUST A TAD FARTHER NORTH THAN THE RAP. BROUGHT TEMPS DOWN A BIT
CLOSE TO THE TN/AR BORDERS...ESPECIALLY OVER WEST KY NEAR THE TN
STATE LINE. NORTH TOWARD I-64 WHERE SUN IS PRESENT TO START THE
DAY...AND DRY AIR HOLDS...TEMPS SHOULD HAVE NO TROUBLE RISING
STEADILY TO HIGHS IN THE MID TO UPPER 50S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 154 AM CDT THU APR 4 2013
RADAR SHOWS RETURNS TO OUR SOUTH PRODUCING SOME LIGHT RAIN. MODELS
LIFT THIS LIGHT RAIN NORTHWARD TODAY...PEAKING THIS AFTERNOON...THEN
SUBSIDING AND EVENTUALLY ENDING TONIGHT. THIS OCCURS AS AN UPPER
LEVEL LOW MOVES FROM THE SRN PLAINS ACROSS THE MID-LOWER MS RIVER
VALLEY. THE 00Z MODELING TRACK OF THIS DRIVING FEATURE IS SLIGHTLY
FURTHER SOUTH THAN PREVIOUS RUNS...SO POPS WILL BE SLIGHTLY LESS
THAN LAST NIGHT/PREVIOUS PACKAGES. OTHERWISE LITTLE CHANGE TO NEAR
TERM FORECAST.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 154 AM CDT THU APR 4 2013
THE DRYING/WARMING WEEKEND IS STILL ON TAP. THE FLOW BECOMES
LARGELY ZONAL AND ACTIVE...WITH A FRONT LAYING ACROSS/JUST TO OUR
NORTH BY SUNDAY AND WAVES OF ENERGY RIDING ALONG IT. DEPENDING
UPON WHERE THIS SETS UP EXACTLY...WE SHOULD SEE POPS ENTER THE
FORECAST BY SUNDAY/MARKING THE BEGINNING OF AN ACTIVE/PERHAPS
INCREASINGLY WET PATTERN AS WE MOVE INTO THE MID WEEK NEXT. THE
EXTENDED RANGE MODELS DEVELOP LARGE SCALE TROFFING OVER THE
CENTRAL U.S....AND THIS REALLY OPENS THE SWLYS ALOFT OVER US (WITH
HIGH PRESSURE OFF THE SE U.S.) AND MAKES FOR A WET/ACTIVE MID
WEEK. THIS INCLUDES AN INCREASING/DAILY POP/THUNDER WHICH MAY
REACH INTO THE LIKELY CATEGORY BUT FOR NOW WE REMAIN AT HIGH
CHANCE AND WILL ADJUST WITH TIME FROM DAY 7.
&&
.AVIATION...
ISSUED AT 1127 AM CDT THU APR 4 2013
WIDESPREAD MID AND HIGH CLOUDS ASSOCIATED WITH A STRONG UPPER LEVEL
LOW PASSING TO OUR SOUTH WILL PERSIST THROUGH EARLY THIS EVENING.
LOW CLOUDS WERE LURKING JUST TO THE SOUTHEAST OF KPAH AT 17Z.
THESE LOWER CLOUDS MAY MOVE INTO THE KPAH AREA THIS AFTERNOON...BUT
THE PROBABILITY WAS TOO LOW TO MENTION CIGS. OPTED INSTEAD TO
MENTION A SCATTERED CLOUD DECK AROUND 4K FEET. SKIES WILL BECOME
CLEAR BY 03Z WITH LIGHT WINDS TONIGHT. WINDS WILL BECOME NORTH
AROUND 5 TO 10 KT FRIDAY MORNING.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
636 PM EDT THU APR 4 2013
.SYNOPSIS...
LOW PRESSURE LIFTS NORTHEAST FROM THE GULF COAST THROUGH TONIGHT.
THIS AREA OF LOW PRESSURE TRACKS ALONG THE SOUTHEAST COAST
OVERNIGHT BEFORE SLIDING OFF THE MID ATLANTIC COAST FRIDAY. HIGH
PRESSURE BUILDS OVER THE REGION SATURDAY AND SHIFTS OFFSHORE
SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
UPDATED GRIDS/ZFP PER RAPIDLY CHANGING CNDTNS ACROSS THE FA ATTM.
NMRS RPTS OF SLEET MIXING IN WITH THE RAIN AT THE ONSET AS FAR
EAST AS VA BCH...SO ADDED IP TO THE GRIDS NEXT FEW HRS. ALSO...DUE
TO THE LARGE TMP/DP TMPS GAP...SFC TMPS QUICKLY FALLING INTO THE
U30S-L40S WHERE PCPN CONTS TO SATURATE THE LYR. THUS...MADE CHANGES
TO TMP GRIDS. CHALLENGING TMP FCST NEXT 6-12 HRS AS READINGS XPCTD
TO LEVEL OFF AT SOME POINT ONCE THE RAIN SATURATES COLUMN THEN STDY
OR SLOWLY RISE AFTR MIDNIGHT IN ADVANCE OF SFC LOW. TMPS MAY EVEN
RISE INTO THE 50S ACROSS NRN OB/VA BCH AREAS LATE TONITE B4 FALLING
BACK INTO THE 40S ONCE THE LOW MOVES NE.
PVS DSCN:
LATEST UPPER AIR ANALYSIS SHOWS A NORTHERN STREAM TROUGH TREKKING
ACROSS ONTARIO THIS AFTN, AS A SOUTHERN STREAM TROUGH IS NOW
ORIENTED OVER TEXARKANA/SOUTHERN MS VLY. AT THE SURFACE, WEAKENING
~1028MB SFC HIGH PRESSURE NOW ORIENTED JUST OFFSHORE, SETTING UP A
HYBRID COLD AIR DAMMING WEDGE STRUCTURE OVER THE REGION. TO THE
SOUTHWEST, A 1012MB LOW PRESSURE CENTER WAS CENTERED OVER THE FL
PANHANDLE...WITH INVERTED COASTAL TROUGH ANALYZED OFFSHORE OF THE
GA/SC COAST.
LOW PRESSURE OVER THE SOUTHEAST WILL LIFT NORTHEAST AS MS VLY
TROUGH WOBBLES EAST SOUTHEAST THROUGH THE EVENING. HAVE SEEN A
HANDFUL OF SLEET REPORTS JUST TO OUR SOUTH/SOUTHWEST THANKS TO
EVAPORATIONAL COOLING IN ANTECEDENT MODIFIED CP AIRMASS.
ISENTROPIC UPGLIDE (290-300K SURFACES) RAMP UP QUICKLY LATE THIS
AFTERNOON AND THIS EVENING AS SSW MID-LEVEL FLOW INCREASES ACROSS
THE SOUTHEAST AND LOWER MID- ATLANTIC. THIS WILL SLOWLY SPREAD RAIN
NORTH-NORTHEAST OVER THE AREA TONIGHT. RUC SOUNDINGS DO ARGUE FOR
A BRIEF PERIOD OF SLEET ACROSS THE PIEDMONT, SOUTH CENTRAL VA/INTR
NE NC, QUICKLY BECOMING ALL RAIN AS WAA CONTINUES AND LLVLS BECOME
SATURATED. CONSIDERING ROAD TEMPS WELL ABOVE FREEZING, THIS SHOULD
BE A MINIMAL IMPACT, BUT NONETHELESS WORTH MENTIONING IN THE GOING
FORECAST.
THE MID-LEVEL TROUGH TRACKS OVER THE DEEP SOUTH TONIGHT...WITH
THE SURFACE LOW PRESSURE TRACKING NE OFF THE COAST ALONG THE
COASTAL BOUNDARY...WITH SOME ADDITIONAL NUDGING FROM THE NORTHERN
STREAM TROUGH. RATHER VIGOROUS VERTICAL ASCENT IS PROGGED TO MOVE
NE ACROSS THE LOCAL AREA BETWEEN 00-09Z...WHICH SHOULD BRING A
PERIOD OF MODERATE COLD RAIN TO MUCH OF THE AREA...CENTERED/HEAVIEST
FROM S-CENTRAL VA TO THE EASTERN SHORE. BRIEF WINDOW OF MAINLY
ELEVATED INSTABILITY ARRIVES AFTER MIDNIGHT. TOTAL TOTALS IN THE
LOW 50S, WITH ENOUGH VERTICAL ASCENT TO OVERCOME NEUTRAL LI
VALUES WOULD ARGUE FOR PERHAPS A RUMBLE OF THUNDER OR TWO ACROSS
THE FAR SOUTHEAST, SO HV ADDED A SLIGHT RISK FOR THUNDER AFTER
MIDNIGHT OVER FAR SE VA/NE NC. RAINFALL RATES SHOULD TAPER OFF
QUICKLY AS THE PRIMARY FORCING MOVES OFF THE COAST TOWARDS DAWN
FRIDAY MORNING. HOWEVER...LINGERING LOW-LEVEL MOISTURE SHOULD
ALLOW FOR STRATUS AND AREAS OF LIGHT RAIN/DRIZZLE. QPF AMOUNTS
RANGE FROM 0.5IN FAR NW...TO 1.25 ACROSS S-CENTRAL VA TO THE
COASTAL ZONES. LOWS SHOULD RANGE FROM THE M/U 30S NW...TO THE MID
40S SE.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
LOW STRATUS AND AREAS OF LIGHT RA/DZ WILL LINGER FRIDAY MORNING,
BEFORE GRADUALLY CLEARING FROM NW TO SE AS WINDS BACK TO THE N-NW.
RAIN CHANCES ALSO DROP OFF QUICKLY AFTER 15Z AS MODEL CROSS
SECTIONS SHOW MID-LEVELS DRYING OUT QUICKLY. HIGHS SHOULD RANGE
FROM THE MID-UPPER 50S ALONG THE IMMEDIATE COAST...TO THE LOW 60S
INLAND.
HIGH PRESSURE BUILDS OVER THE AREA LATE FRIDAY NIGHT THROUGH
SATURDAY MORNING, BEFORE SLIDING OFFSHORE LATER SATURDAY.
QUASI-ZONAL/FLAT FLOW ALOFT ALLOWS DRIER AIR TO FILTER IN FROM THE
WEST FRIDAY AND SATURDAY. THUS, APART FROM SOME DIURNALLY DRIVEN
CUMULUS SATURDAY MORNING/AFTN, COURTESY OF ONSHORE (E-SE) LOW LEVEL
FLOW, EXPECT A MAINLY CLEAR SKY DURING THIS PERIOD. BY SUNDAY, FLOW
ALOFT OVER THE EASTERN THIRD OF THE COUNTRY BECOMES S-SW, AS UPPER
TROUGH COMES ASHORE THE PACIFIC COAST. THIS SHOULD EVENTUALLY LEAD
TO A WARM-UP BY LATE IN THE WEEKEND. CLEAR SKY/DRY AIRMASS SHOULD
BRING CHILLY EARLY MORNING SATURDAY AND SUNDAY MORNINGS. LOWS FROM
THE MID 30S N/NW TO LOW 40S SE COAST SAT MORNING...U30S TO MID 40S
SUNDAY MORNING. FORECAST HIGHS SAT RANGE FROM THE UPPER 40S/LOW
50S ALONG THE IMMEDIATE ATLANTIC COAST OF THE EASTERN SHORE TO
LOW 60S FROM THE I-95 CORRIDOR WEST. HIGHS WARM WELL INTO THE 60S
ON SUNDAY, WITH LOW 70S LIKELY WEST OF THE CHES BAY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
12Z GFS/ECMWF IN GENERAL AGREEMENT SUN NGT INTO TUE MORNG...THEN
ARE QUITE DIFFERENT FOR TUE THRU THU. GFS MAINTAINS A WARMER
SCENARIO THRU THE PERIOD...KEEPING A FRNTL BOUNDARY N OF THE CWA
WITH AN UA RDG BLDNG OVR THE MID ATLC REGION TUE THRU WED...THEN
IT SLIDES OUT TO SEA WED NGT AND THU. WHILE...THE ECMWF KEEPS THE
FRNTL BOUNDARY NW OR N OF THE CWA SUN NGT INTO TUE MORNG...THEN
DROPS THE FRNT DOWN ACRS THE AREA TUE AFTN INTO WED...THEN
LINGERING THE FRNT NEAR THE VA/NC BORDER THRU THU. AT THIS TIME
GOING WITH THE WARMER GFS MODEL THRU THE PERIOD...WITH JUST A SLGT
OR SML CHC FOR SHOWERS POSSIBLE WED THRU THU. MAX TEMPS WILL RANGE
FM THE MID 60S TO MID 70S MON...AND IN THE UPR 60S TO UPR 70S TUE
THRU THU. MIN TEMPS WILL BE IN THE MID 40S TO LWR 50S MON
MORNG...AND MAINLY IN THE LWR TO MID 50S TUE...WED...AND THU
MORNGS.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS WILL CONTINUE THIS AFTERNOON AS HIGH PRESSURE
RETREATS TO THE EAST. HIGH CLOUDS WILL CONTINUE TO OVERSPREAD THE
TAF SITES IN ADVANCE OF A LOW PRESSURE SYSTEM SLOWLY APPROACHING
FROM THE SW. CIGS BEGIN TO LOWER LATER THIS AFTERNOON AS THE LOW
MOVES NORTHWARD ALONG THE SE COAST. RAIN BEGINS BETWEEN 22Z/TODAY
AND 01Z/FRI THEN CONTINUES OVERNIGHT BEFORE TAPERING OFF AROUND
DAYBREAK FRIDAY. IFR CONDITIONS (MAINLY FOR CIGS) WILL BE LIKELY
TONIGHT AT ALL TAF SITES...WITH PERIODS OF MODERATE RAIN AS WELL.
LIFR CONDITIONS ARE POSSIBLE BUT NOT CONFIDENT ENUF TO INCLUDE IN
THE TAFS ATTM. HI PRES BLDS IN LATE FRI INTO THE WEEKEND LEADING
TO VFR CONDITIONS.
&&
.MARINE...
ESE THRU S FLO 5 TO 15 KTS EARLY THIS EVENG...WILL BECOME NE AND
INCREASE TO 15 TO 20 KTS TNGT...AS INTENSIFYING LO PRES MOVES FM
THE SE CST NNE TO JUST OFF THE MID ATLC CST BY 12Z FRI. THAT LO
WILL CONTINUE TO INTENSIFY DURING FRI...AS IT MOVES AWAY TO THE NE
AND HI PRES STARTS TO BLD IN FM THE NW. THE HI WILL MOVE TO RIGHT
OVR THE REGION SAT MORNG. THIS WILL RESULT IN STRONG N WNDS FM FRI
MORNG INTO SAT MORNG...WITH SCA`S FOR ALL WTRS EXCEPT THE RIVERS.
HI PRES WILL THEN SLIDE OFF THE CST FOR SUN THRU AT LEAST MON.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 11 PM THIS EVENING TO 7 PM EDT
FRIDAY FOR ANZ630>632-634.
SMALL CRAFT ADVISORY FROM 6 AM TO 7 PM EDT FRIDAY FOR ANZ633.
SMALL CRAFT ADVISORY FROM 4 AM FRIDAY TO NOON EDT SATURDAY FOR
ANZ652-654.
SMALL CRAFT ADVISORY FROM 1 AM FRIDAY TO NOON EDT SATURDAY FOR
ANZ656.
SMALL CRAFT ADVISORY FROM 6 AM FRIDAY TO NOON EDT SATURDAY FOR
ANZ650.
SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO NOON EDT
SATURDAY FOR ANZ658.
&&
$$
SYNOPSIS...MAM
NEAR TERM...MPR/MAM
SHORT TERM...MAM
LONG TERM...TMG
AVIATION...MAS
MARINE...TMG
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
450 PM EDT THU APR 4 2013
.SYNOPSIS...
LOW PRESSURE LIFTS NORTHEAST FROM THE GULF COAST THROUGH TONIGHT.
THIS AREA OF LOW PRESSURE TRACKS ALONG THE SOUTHEAST COAST
OVERNIGHT BEFORE SLIDING OFF THE MID ATLANTIC COAST FRIDAY. HIGH
PRESSURE BUILDS OVER THE REGION SATURDAY AND SHIFTS OFFSHORE
SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
LATEST UPPER AIR ANALYSIS SHOWS A NORTHERN STREAM TROUGH TREKKING
ACROSS ONTARIO THIS AFTN, AS A SOUTHERN STREAM TROUGH IS NOW
ORIENTED OVER TEXARKANA/SOUTHERN MS VLY. AT THE SURFACE, WEAKENING
~1028MB SFC HIGH PRESSURE NOW ORIENTED JUST OFFSHORE, SETTING UP A
HYBRID COLD AIR DAMMING WEDGE STRUCTURE OVER THE REGION. TO THE
SOUTHWEST, A 1012MB LOW PRESSURE CENTER WAS CENTERED OVER THE FL
PANHANDLE...WITH INVERTED COASTAL TROUGH ANALYZED OFFSHORE OF THE
GA/SC COAST.
LOW PRESSURE OVER THE SOUTHEAST WILL LIFT NORTHEAST AS MS VLY
TROUGH WOBBLES EAST SOUTHEAST THROUGH THE EVENING. HAVE SEEN A
HANDFUL OF SLEET REPORTS JUST TO OUR SOUTH/SOUTHWEST THANKS TO
EVAPORATIONAL COOLING IN ANTECEDENT MODIFIED CP AIRMASS.
ISENTROPIC UPGLIDE (290-300K SURFACES) RAMP UP QUICKLY LATE THIS
AFTERNOON AND THIS EVENING AS SSW MID-LEVEL FLOW INCREASES ACROSS
THE SOUTHEAST AND LOWER MID- ATLANTIC. THIS WILL SLOWLY SPREAD RAIN
NORTH-NORTHEAST OVER THE AREA TONIGHT. RUC SOUNDINGS DO ARGUE FOR
A BRIEF PERIOD OF SLEET ACROSS THE PIEDMONT, SOUTH CENTRAL VA/INTR
NE NC, QUICKLY BECOMING ALL RAIN AS WAA CONTINUES AND LLVLS BECOME
SATURATED. CONSIDERING ROAD TEMPS WELL ABOVE FREEZING, THIS SHOULD
BE A MINIMAL IMPACT, BUT NONETHELESS WORTH MENTIONING IN THE GOING
FORECAST.
THE MID-LEVEL TROUGH TRACKS OVER THE DEEP SOUTH TONIGHT...WITH
THE SURFACE LOW PRESSURE TRACKING NE OFF THE COAST ALONG THE
COASTAL BOUNDARY...WITH SOME ADDITIONAL NUDGING FROM THE NORTHERN
STREAM TROUGH. RATHER VIGOROUS VERTICAL ASCENT IS PROGGED TO MOVE
NE ACROSS THE LOCAL AREA BETWEEN 00-09Z...WHICH SHOULD BRING A
PERIOD OF MODERATE COLD RAIN TO MUCH OF THE AREA...CENTERED/HEAVIEST
FROM S-CENTRAL VA TO THE EASTERN SHORE. BRIEF WINDOW OF MAINLY
ELEVATED INSTABILITY ARRIVES AFTER MIDNIGHT. TOTAL TOTALS IN THE
LOW 50S, WITH ENOUGH VERTICAL ASCENT TO OVERCOME NEUTRAL LI
VALUES WOULD ARGUE FOR PERHAPS A RUMBLE OF THUNDER OR TWO ACROSS
THE FAR SOUTHEAST, SO HV ADDED A SLIGHT RISK FOR THUNDER AFTER
MIDNIGHT OVER FAR SE VA/NE NC. RAINFALL RATES SHOULD TAPER OFF
QUICKLY AS THE PRIMARY FORCING MOVES OFF THE COAST TOWARDS DAWN
FRIDAY MORNING. HOWEVER...LINGERING LOW-LEVEL MOISTURE SHOULD
ALLOW FOR STRATUS AND AREAS OF LIGHT RAIN/DRIZZLE. QPF AMOUNTS
RANGE FROM 0.5IN FAR NW...TO 1.25 ACROSS S-CENTRAL VA TO THE
COASTAL ZONES. LOWS SHOULD RANGE FROM THE M/U 30S NW...TO THE MID
40S SE.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
LOW STRATUS AND AREAS OF LIGHT RA/DZ WILL LINGER FRIDAY MORNING,
BEFORE GRADUALLY CLEARING FROM NW TO SE AS WINDS BACK TO THE N-NW.
RAIN CHANCES ALSO DROP OFF QUICKLY AFTER 15Z AS MODEL CROSS
SECTIONS SHOW MID-LEVELS DRYING OUT QUICKLY. HIGHS SHOULD RANGE
FROM THE MID-UPPER 50S ALONG THE IMMEDIATE COAST...TO THE LOW 60S
INLAND.
HIGH PRESSURE BUILDS OVER THE AREA LATE FRIDAY NIGHT THROUGH
SATURDAY MORNING, BEFORE SLIDING OFFSHORE LATER SATURDAY.
QUASI-ZONAL/FLAT FLOW ALOFT ALLOWS DRIER AIR TO FILTER IN FROM THE
WEST FRIDAY AND SATURDAY. THUS, APART FROM SOME DIURNALLY DRIVEN
CUMULUS SATURDAY MORNING/AFTN, COURTESY OF ONSHORE (E-SE) LOW LEVEL
FLOW, EXPECT A MAINLY CLEAR SKY DURING THIS PERIOD. BY SUNDAY, FLOW
ALOFT OVER THE EASTERN THIRD OF THE COUNTRY BECOMES S-SW, AS UPPER
TROUGH COMES ASHORE THE PACIFIC COAST. THIS SHOULD EVENTUALLY LEAD
TO A WARM-UP BY LATE IN THE WEEKEND. CLEAR SKY/DRY AIRMASS SHOULD
BRING CHILLY EARLY MORNING SATURDAY AND SUNDAY MORNINGS. LOWS FROM
THE MID 30S N/NW TO LOW 40S SE COAST SAT MORNING...U30S TO MID 40S
SUNDAY MORNING. FORECAST HIGHS SAT RANGE FROM THE UPPER 40S/LOW
50S ALONG THE IMMEDIATE ATLANTIC COAST OF THE EASTERN SHORE TO
LOW 60S FROM THE I-95 CORRIDOR WEST. HIGHS WARM WELL INTO THE 60S
ON SUNDAY, WITH LOW 70S LIKELY WEST OF THE CHES BAY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
12Z GFS/ECMWF IN GENERAL AGREEMENT SUN NGT INTO TUE MORNG...THEN
ARE QUITE DIFFERENT FOR TUE THRU THU. GFS MAINTAINS A WARMER
SCENARIO THRU THE PERIOD...KEEPING A FRNTL BOUNDARY N OF THE CWA
WITH AN UA RDG BLDNG OVR THE MID ATLC REGION TUE THRU WED...THEN
IT SLIDES OUT TO SEA WED NGT AND THU. WHILE...THE ECMWF KEEPS THE
FRNTL BOUNDARY NW OR N OF THE CWA SUN NGT INTO TUE MORNG...THEN
DROPS THE FRNT DOWN ACRS THE AREA TUE AFTN INTO WED...THEN
LINGERING THE FRNT NEAR THE VA/NC BORDER THRU THU. AT THIS TIME
GOING WITH THE WARMER GFS MODEL THRU THE PERIOD...WITH JUST A SLGT
OR SML CHC FOR SHOWERS POSSIBLE WED THRU THU. MAX TEMPS WILL RANGE
FM THE MID 60S TO MID 70S MON...AND IN THE UPR 60S TO UPR 70S TUE
THRU THU. MIN TEMPS WILL BE IN THE MID 40S TO LWR 50S MON
MORNG...AND MAINLY IN THE LWR TO MID 50S TUE...WED...AND THU
MORNGS.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
VFR CONDITIONS WILL CONTINUE THIS AFTERNOON AS HIGH PRESSURE
RETREATS TO THE EAST. HIGH CLOUDS WILL CONTINUE TO OVERSPREAD THE
TAF SITES IN ADVANCE OF A LOW PRESSURE SYSTEM SLOWLY APPROACHING
FROM THE SW. CIGS BEGIN TO LOWER LATER THIS AFTERNOON AS THE LOW
MOVES NORTHWARD ALONG THE SE COAST. RAIN BEGINS BETWEEN 22Z/TODAY
AND 01Z/FRI THEN CONTINUES OVERNIGHT BEFORE TAPERING OFF AROUND
DAYBREAK FRIDAY. IFR CONDITIONS (MAINLY FOR CIGS) WILL BE LIKELY
TONIGHT AT ALL TAF SITES...WITH PERIODS OF MODERATE RAIN AS WELL.
LIFR CONDITIONS ARE POSSIBLE BUT NOT CONFIDENT ENUF TO INCLUDE IN
THE TAFS ATTM. HI PRES BLDS IN LATE FRI INTO THE WEEKEND LEADING
TO VFR CONDITIONS.
&&
.MARINE...
ESE THRU S FLO 5 TO 15 KTS EARLY THIS EVENG...WILL BECOME NE AND
INCREASE TO 15 TO 20 KTS TNGT...AS INTENSIFYING LO PRES MOVES FM
THE SE CST NNE TO JUST OFF THE MID ATLC CST BY 12Z FRI. THAT LO
WILL CONTINUE TO INTENSIFY DURING FRI...AS IT MOVES AWAY TO THE NE
AND HI PRES STARTS TO BLD IN FM THE NW. THE HI WILL MOVE TO RIGHT
OVR THE REGION SAT MORNG. THIS WILL RESULT IN STRONG N WNDS FM FRI
MORNG INTO SAT MORNG...WITH SCA`S FOR ALL WTRS EXCEPT THE RIVERS.
HI PRES WILL THEN SLIDE OFF THE CST FOR SUN THRU AT LEAST MON.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 11 PM THIS EVENING TO 7 PM EDT
FRIDAY FOR ANZ630>632-634.
SMALL CRAFT ADVISORY FROM 6 AM TO 7 PM EDT FRIDAY FOR ANZ633.
SMALL CRAFT ADVISORY FROM 4 AM FRIDAY TO NOON EDT SATURDAY FOR
ANZ652-654.
SMALL CRAFT ADVISORY FROM 1 AM FRIDAY TO NOON EDT SATURDAY FOR
ANZ656.
SMALL CRAFT ADVISORY FROM 6 AM FRIDAY TO NOON EDT SATURDAY FOR
ANZ650.
SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO NOON EDT
SATURDAY FOR ANZ658.
&&
$$
SYNOPSIS...MAM
NEAR TERM...AJZ/MAM
SHORT TERM...MAM
LONG TERM...TMG
AVIATION...MAS
MARINE...TMG
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
410 PM EDT THU APR 4 2013
.SYNOPSIS...
LOW PRESSURE LIFTS NORTHEAST FROM THE GULF COAST THROUGH TONIGHT.
THIS AREA OF LOW PRESSURE TRACKS ALONG THE SOUTHEAST COAST
OVERNIGHT BEFORE SLIDING OFF THE MID ATLANTIC COAST FRIDAY. HIGH
PRESSURE BUILDS OVER THE REGION SATURDAY AND SHIFTS OFFSHORE
SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
LATEST UPPER AIR ANALYSIS SHOWS A NORTHERN STREAM TROUGH TREKKING
ACROSS ONTARIO THIS AFTN, AS A SOUTHERN STREAM TROUGH IS NOW
ORIENTED OVER TEXARKANA/SOUTHERN MS VLY. AT THE SURFACE, WEAKENING
~1028MB SFC HIGH PRESSURE NOW ORIENTED JUST OFFSHORE, SETTING UP A
HYBRID COLD AIR DAMMING WEDGE STRUCTURE OVER THE REGION. TO THE
SOUTHWEST, A 1012MB LOW PRESSURE CENTER WAS CENTERED OVER THE FL
PANHANDLE...WITH INVERTED COASTAL TROUGH ANALYZED OFFSHORE OF THE
GA/SC COAST.
LOW PRESSURE OVER THE SOUTHEAST WILL LIFT NORTHEAST AS MS VLY
TROUGH WOBBLES EAST SOUTHEAST THROUGH THE EVENING. HAVE SEEN A
HANDFUL OF SLEET REPORTS JUST TO OUR SOUTH/SOUTHWEST THANKS TO
EVAPORATIONAL COOLING IN ANTECEDENT MODIFIED CP AIRMASS.
ISENTROPIC UPGLIDE (290-300K SURFACES) RAMP UP QUICKLY LATE THIS
AFTERNOON AND THIS EVENING AS SSW MID-LEVEL FLOW INCREASES ACROSS
THE SOUTHEAST AND LOWER MID- ATLANTIC. THIS WILL SLOWLY SPREAD RAIN
NORTH-NORTHEAST OVER THE AREA TONIGHT. RUC SOUNDINGS DO ARGUE FOR
A BRIEF PERIOD OF SLEET ACROSS THE PIEDMONT, SOUTH CENTRAL VA/INTR
NE NC, QUICKLY BECOMING ALL RAIN AS WAA CONTINUES AND LLVLS BECOME
SATURATED. CONSIDERING ROAD TEMPS WELL ABOVE FREEZING, THIS SHOULD
BE A MINIMAL IMPACT, BUT NONETHELESS WORTH MENTIONING IN THE GOING
FORECAST.
THE MID-LEVEL TROUGH TRACKS OVER THE DEEP SOUTH TONIGHT...WITH
THE SURFACE LOW PRESSURE TRACKING NE OFF THE COAST ALONG THE
COASTAL BOUNDARY...WITH SOME ADDITIONAL NUDGING FROM THE NORTHERN
STREAM TROUGH. RATHER VIGOROUS VERTICAL ASCENT IS PROGGED TO MOVE
NE ACROSS THE LOCAL AREA BETWEEN 00-09Z...WHICH SHOULD BRING A
PERIOD OF MODERATE COLD RAIN TO MUCH OF THE AREA...CENTERED/HEAVIEST
FROM S-CENTRAL VA TO THE EASTERN SHORE. BRIEF WINDOW OF MAINLY
ELEVATED INSTABILITY ARRIVES AFTER MIDNIGHT. TOTAL TOTALS IN THE
LOW 50S, WITH ENOUGH VERTICAL ASCENT TO OVERCOME NEUTRAL LI
VALUES WOULD ARGUE FOR PERHAPS A RUMBLE OF THUNDER OR TWO ACROSS
THE FAR SOUTHEAST, SO HV ADDED A SLIGHT RISK FOR THUNDER AFTER
MIDNIGHT OVER FAR SE VA/NE NC. RAINFALL RATES SHOULD TAPER OFF
QUICKLY AS THE PRIMARY FORCING MOVES OFF THE COAST TOWARDS DAWN
FRIDAY MORNING. HOWEVER...LINGERING LOW-LEVEL MOISTURE SHOULD
ALLOW FOR STRATUS AND AREAS OF LIGHT RAIN/DRIZZLE. QPF AMOUNTS
RANGE FROM 0.5IN FAR NW...TO 1.25 ACROSS S-CENTRAL VA TO THE
COASTAL ZONES. LOWS SHOULD RANGE FROM THE M/U 30S NW...TO THE MID
40S SE.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
LOW STRATUS AND AREAS OF LIGHT RA/DZ WILL LINGER FRIDAY MORNING,
BEFORE GRADUALLY CLEARING FROM NW TO SE AS WINDS BACK TO THE N-NW.
RAIN CHANCES ALSO DROP OFF QUICKLY AFTER 15Z AS MODEL CROSS
SECTIONS SHOW MID-LEVELS DRYING OUT QUICKLY. HIGHS SHOULD RANGE
FROM THE MID-UPPER 50S ALONG THE IMMEDIATE COAST...TO THE LOW 60S
INLAND.
HIGH PRESSURE BUILDS OVER THE AREA LATE FRIDAY NIGHT THROUGH
SATURDAY MORNING, BEFORE SLIDING OFFSHORE LATER SATURDAY.
QUASI-ZONAL/FLAT FLOW ALOFT ALLOWS DRIER AIR TO FILTER IN FROM THE
WEST FRIDAY AND SATURDAY. THUS, APART FROM SOME DIURNALLY DRIVEN
CUMULUS SATURDAY MORNING/AFTN, COURTESY OF ONSHORE (E-SE) LOW LEVEL
FLOW, EXPECT A MAINLY CLEAR SKY DURING THIS PERIOD. BY SUNDAY, FLOW
ALOFT OVER THE EASTERN THIRD OF THE COUNTRY BECOMES S-SW, AS UPPER
TROUGH COMES ASHORE THE PACIFIC COAST. THIS SHOULD EVENTUALLY LEAD
TO A WARM-UP BY LATE IN THE WEEKEND. CLEAR SKY/DRY AIRMASS SHOULD
BRING CHILLY EARLY MORNING SATURDAY AND SUNDAY MORNINGS. LOWS FROM
THE MID 30S N/NW TO LOW 40S SE COAST SAT MORNING...U30S TO MID 40S
SUNDAY MORNING. FORECAST HIGHS SAT RANGE FROM THE UPPER 40S/LOW
50S ALONG THE IMMEDIATE ATLANTIC COAST OF THE EASTERN SHORE TO
LOW 60S FROM THE I-95 CORRIDOR WEST. HIGHS WARM WELL INTO THE 60S
ON SUNDAY, WITH LOW 70S LIKELY WEST OF THE CHES BAY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
12Z GFS/ECMWF IN GENERAL AGREEMENT SAT NGT INTO MON NGT...THEN
DIFFER TUE THRU WED WITH REGARD TO A BACKDOOR FRONT...WHICH THE
ECMWF BRINGS DOWN INTO AND ACRS THE CWA TUE AFTN THRU WED. THE GFS
BLDS THE UA RDG OVR THE MID ATLC REGION AND OFF THE CST DURING
THIS TIME PERIOD. AT THIS TIME...LEANING TWD THE WARMER AND DRIER
GFS THRU THE PERIOD...WITH ONLY A SLGT CHC OF SHOWERS FOR WED. SFC
HI PRES WILL SLIDE OFF THE MID ATLC CST SAT NGT AND SUN...THEN
MOVE FARTHER OUT TO SEA DURING WED. MAX TEMPS WILL RANGE THRU THE
60S SUN...THEN GENERALLY RANGE FM THE MID 60S TO MID 70S MON THRU
WED. MIN TEMPS WILL BE IN THE MID 30S TO ARND 40 SUN MORNG...IN
THE MID 40S TO ARND 50 MON MORNG...IN THE UPR 40S TO LWR 50S TUE
MORNG...AND IN THE LWR TO MID 50S WED MORNG.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
VFR CONDITIONS WILL CONTINUE THIS AFTERNOON AS HIGH PRESSURE
RETREATS TO THE EAST. HIGH CLOUDS WILL CONTINUE TO OVERSPREAD THE
TAF SITES IN ADVANCE OF A LOW PRESSURE SYSTEM SLOWLY APPROACHING
FROM THE SW. CIGS BEGIN TO LOWER LATER THIS AFTERNOON AS THE LOW
MOVES NORTHWARD ALONG THE SE COAST. RAIN BEGINS BETWEEN 22Z/TODAY
AND 01Z/FRI THEN CONTINUES OVERNIGHT BEFORE TAPERING OFF AROUND
DAYBREAK FRIDAY. IFR CONDITIONS (MAINLY FOR CIGS) WILL BE LIKELY
TONIGHT AT ALL TAF SITES...WITH PERIODS OF MODERATE RAIN AS WELL.
LIFR CONDITIONS ARE POSSIBLE BUT NOT CONFIDENT ENUF TO INCLUDE IN
THE TAFS ATTM. HI PRES BLDS IN LATE FRI INTO THE WEEKEND LEADING
TO VFR CONDITIONS.
&&
.MARINE...
LIGHT NE FLOW THIS MORNING BECOMES E AND SE THIS AFTERNOON AS HIGH
PRESSURE SLIDES OFF THE CST...FOLLOWED BY INTENSIFYING LOW PRESSURE
TRACKING FROM THE GULF COAST STATES NE UP AND OFF THE MID ATLC CST
THIS EVENING THRU FRIDAY MORNING. SOLID SCA CONDITIONS ARE EXPECTED
TO DEVELOP ON THE COASTAL WATERS TONIGHT AS THE LOW INTENSIFIES AND
SEAS BUILD TO AT LEAST 5-8 FT. WIND GUSTS TO 30 KT WILL ALSO BE
POSSIBLE ON FRIDAY. ON THE CHESAPEAKE BAY...WINDS INCREASE TO SCA
LEVELS THIS EVENING AND CONTINUE THRU FRIDAY. HAVE ACCORDINGLY
HOISTED SCA HEADLINES FOR THE BAY AND COASTAL WATERS BEGINNING THIS
EVENING. BECAUSE OF HIGH CONFIDENCE IN SEAS REMAINING ELEVATED THRU
AT LEAST FRI NIGHT...HAVE THE SCA`S FOR THE COASTAL WATERS CONTINUING
THROUGH 6 AM SAT. CONFIDENCE NOT HIGH ENOUGH ATTM TO ISSUE ANY SCA
HEADLINES ON THE CURRITUCK SOUND AND THE EASTERN VA RIVERS...SO WILL
LET DAY SHIFT RE-EVALUATE AND ISSUE AS NECESSARY. HIGH PRES WILL
BUILD BACK OVR THE REGION FOR SATURDAY...THEN SLIDES OFF THE COAST
FOR SUN AND MON.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 11 PM THIS EVENING TO 7 PM EDT
FRIDAY FOR ANZ630>632-634.
SMALL CRAFT ADVISORY FROM 4 AM FRIDAY TO 6 AM EDT SATURDAY FOR
ANZ652-654.
SMALL CRAFT ADVISORY FROM 1 AM FRIDAY TO 6 AM EDT SATURDAY FOR
ANZ656.
SMALL CRAFT ADVISORY FROM 6 AM FRIDAY TO 6 AM EDT SATURDAY FOR
ANZ650.
SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 6 AM EDT
SATURDAY FOR ANZ658.
&&
$$
SYNOPSIS...MAM
NEAR TERM...AJZ/MAM
SHORT TERM...MAM
LONG TERM...TMG
AVIATION...JDM/MAS
MARINE...TMG
AREA FORECAST DISCUSSION
NWS GAYLORD MI
347 PM EDT THU APR 4 2013
.SYNOPSIS...
ISSUED AT 344 PM EDT THU APR 4 2013
A COLD FRONT IS MOVING THROUGH NORTHERN MICHIGAN...BRINGING A
PERIOD OF LIGHT RAIN AND SNOW FOR THIS AFTERNOON AND TONIGHT.
SETTLED WEATHER WILL RETURN FOR A SHORT TIME ON FRIDAY...BEFORE
ANOTHER STORM SYSTEM MOVES INTO NORTHERN MICHIGAN...BRINGING RAIN
AND SNOW MIXED FOR SATURDAY INTO SUNDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 344 PM EDT THU APR 4 2013
THE CURRENT RADAR SHOWS A NARROW BAND OF PCPN SLOWLY DROPPING SOUTH
ACROSS NORTHERN LOWER MICHIGAN. THIS NARROW AREA OF PRECIPITATION IS
THE RESULT OF A COLD FRONT SINKING SOUTH OVER THE REGION. VIS SAT
AND SFC OBS SHOW LIMITED MOISTURE EITHER SIDE OF THE BOUNDARY...WITH
MOSTLY SUNNY SKIES OVER MUCH OF CENTRAL AND SOUTHERN MICHIGAN. SUN
OVER THE SRN CWA FROM EARLIER TODAY...HAS ALLOWED AFTERNOON TEMPS IN
THESE AREAS TO WARM QUICKLY INTO THE MID AND UPPER 40S...WHILE
TEMPS REMAIN IN THE 30S OVER ERN UPPER NORTH OF THE BOUNDARY.
OVERALL THE MAIN FORECAST CONCERNS TONIGHT THROUGH FRIDAY WILL BE
TIMING AND TYPE OF PCPN TONIGHT WITH THE APPROACHING FRONT...ALONG
WITH ANY LAKE INDUCED SNOWS FRIDAY ON THE BACKSIDE OF THE COLD
FRONT.
THE STORM SYSTEM CURRENTLY MOVING ACRS ONTARIO WILL QUICKLY EXIT
INTO QUEBEC THIS EVENING. A COLD FRONT ASSOCIATED WITH THIS SYSTEM...
WILL CONT TO DROP SOUTH ACRS NRN LWR MI THIS EVENING BEFORE EXITING
EAST. EXPECT THE FRONT TO HAVE CLEARED NORTHERN LOWER MICHIGAN
BTWN 03Z AND 06Z. THE ONLY PCPN ASSOCIATED WITH THIS BOUNDARY HAS
BEEN LOCATED RIGHT ALONG THE FRONT...DUE TO THE EXTREMELY DRY AIR
LOCATED OVER THE GREAT LAKES. HOWEVER SFC DEW PTS EVENTUALLY
INCREASED FROM THE TEENS INTO THE MID 20S OVER THE STRAITS AS THE
FRONT APPROACHED (ENOUGH TO GENERATE PCPN). HOWEVER PCPN TYPE AND
CHC OVER THE REST OF THE CWA WILL BE DIFFICULT THIS EVENING AS THE
FRONT DIPS SOUTH. TO THIS POINT...ALL OF THE PCPN HAS BEEN IN THE
FORM OF SNOW OVER ERN UPPER AND THE STRAITS. THE LATEST RUC MODEL
SOUNDINGS SHOW AN INVERTED V SIGNATURE IN THE LOWEST LAYERS FROM
GAYLORD SOUTH TO THE SAGINAW BAY THIS EVENING...WITH OTHERWISE
EXTREMELY DRY AIR ABOVE 850MB. ADDING COMPLICATIONS TO PCPN TYPE
THIS EVENING IS THE VERTICAL TEMP PROFILES...AS MOST OF NRN LWR
WARMED WELL INTO THE MID AND UPPER 40S DUE TO SOUTHWEST WINDS AND
FULL SUN IN ADVANCE OF THE FRONT. HOWEVER PROGGED 850MB WET BULB TEMPS
WOULD SUGGEST ENOUGH EVAP COOLING WITH ONSET OF ADVANCING MSTR TO AT
LEAST MENTION A RAIN/SNOW MIX. OVERALL WILL CONTINUE THE LATEST
TREND OF CHC POPS RAIN/SNOW MIXED OVER THE SRN HALF OF THE CWA AND
SAGINAW BAY INTO THIS EVENING.
COLDER AIR AND NORTHWEST FLOW RE-SETTLES INTO THE REGION OVERNIGHT
AND FRIDAY ON THE BACK SIDE OF THE EXITING BOUNDARY. 850MB TEMPS
QUICKLY DROP FROM ARND -4C THIS EVENING TO BETWEEN -12C AND -14C BY
12Z FRIDAY. SFC-850MB WINDS TURN FROM THE SOUTHWEST THIS EVENING IN
ADVANCE OF THE BOUNDARY TO NNW FRIDAY. MODEL SOUNDINGS SUGGEST INVERSION
HEIGHTS INCREASING TO NEAR 5K FT WHILE LINGERING LOW LVL MSTR EXTENDS
TO AROUND THE -12C ISOTHERM. OVERALL MENTION CHC POPS IN NORTH FLOW
SNOW BELTS EARLY FRIDAY. OTHERWISE WILL MENTION AT LEAST PARTLY
SUNNY SKIES OVER THE REST OF THE CWA FRIDAY. WILL MENTION COOLER AFTN
TEMPS FRIDAY...RANGING FROM AROUND FREEZING OVER ERN UPPER AND THE
STRAITS TO THE LOWER 40S NEAR SAGINAW BAY.
&&
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 344 PM EDT THU APR 4 2013
LITTLE CHANGE FROM WHAT WAS SEEN YESTERDAY...WITH STILL PLENTY OF
POTENTIAL FOR A VERY ACTIVE NEXT 7 DAYS OF WEATHER AS PERSISTENT
-AO RELAXES AND DEEP SOUTHWEST MOISTURE RICH FLOW DEVELOPS ON
FRONTSIDE OF DIGGING INTERMOUNTAIN WEST ENERGY. BIG WILD CARD
REMAINS POTENTIAL INTERACTION WITH POLAR LOW SET TO ROTATE ACROSS
EASTERN CANADA. EVENTUAL PLACEMENT OF THIS FEATURE WILL BE KEY IN
DETERMINING LOCATION OF INTENSE LOW LEVEL THERMAL BOUNDARY AND
SUBSEQUENT PATHWAY FOR ENERGY ROTATING OUT OF WESTERN TROUGH AXIS.
WHILE ABOVE REMAINS A VERY LOW CONFIDENCE PORTION OF THE
FORECAST...LEAD WAVE APPROACHING THE PACIFIC NORTHWEST (NICELY
ILLUSTRATED ON LATEST WATER VAPOR IMAGERY) NOW WELL AGREED UPON TO
IMPACT OUR WEATHER INTO THE START OF THIS WEEKEND. THIS WAVE WILL
BRING ANOTHER BOUT OF WINTRY WEATHER TO THE NORTH WOODS
SATURDAY...WITH INCREASING CONFIDENCE PARTS OF EASTERN UPPER WILL
SEE A PERIOD OF ACCUMULATING SNOW. FORECAST CONCERNS INITIALLY
DEAL WITH THIS LATTER SYSTEM...SPECIFICALLY SNOWFALL ACCUMULATIONS
FOR EASTERN UPPER. MUCH MORE OF PROBABILISTIC APPROACH TAKING FOR
THE REMAINDER OF THE FORECAST...WITH AT LEAST SOME ATTEMPT AT
ADDRESSING MULTI- PERIOD PRECIP CHANCES AND TEMPERATURE TRENDS.
GUIDANCE HAS LOCKED IN A SOLUTION SENDING PACIFIC NORTHWEST WAVE
RAPIDLY EAST INTO THE NORTHERN PLAIN FRIDAY NIGHT...AND THROUGH
NORTHERN MICHIGAN BY SATURDAY NIGHT. WEAKISH COUPLED JET STRUCTURE
AND LOW LEVEL THERMAL BOUNDARY EXPECTED TO ENTICE RESPECTABLE
SURFACE LOW PRESSURE DEVELOPMENT WITH THIS MID LEVEL WAVE...ITSELF
EXPECTED TO SLICE THROUGH THE HEART OF NORTHERN LOWER MICHIGAN
SATURDAY EVENING. ALTHOUGH WAVE ITSELF AND SURFACE FEATURE NOTHING
TO WRITE HOME ABOUT...ACCOMPANYING DYNAMICS REMAIN IMPRESSIVE INDEED.
MULTI-PERIOD TRENDS CONTINUE TO SUPPORT AGGRESSIVE WAA DRIVEN
DYNAMICS...WITH NEAR 60 KNOT SOUTHWEST FLOW LOW LEVEL JET
PERPENDICULAR TO THE 290K-295K PRESSURE SURFACES. DEEP LAYER FGEN
SIGNAL ALSO PRESENT ALONG RETREATING COLD DOME...COLLOCATED NICELY
WITH MAX WAA UPGLIDE ON NOSE OF LOW LEVEL JET. BEST JUXTAPOSITION OF
THE ABOVE EXPECTED ACROSS FAR NORTHERN LOWER AND AREAS NORTH OF THE
BRIDGE SATURDAY INTO SATURDAY EVENING. SYSTEM HAS A NICE SUBTROPICAL
PACIFIC MOISTURE PLUME ALREADY ASSOCIATED WITH IT...SOME OF WHICH
WILL BE ADVECTED INTO OUR AREA AS SYSTEM APPROACHES. COMBINE THIS
WITH BRIEF WINDOW FOR SOME WESTERN GULF OF MEXICO MOISTURE
CONTRIBUTION...AND PWAT VALUES SURGE TO AOA 0.75 INCHES LEVELS BY
LATER SATURDAY. SAID ISENTROPIC SURFACES ALSO SHOW VERY RESPECTABLE
MOISTURE...WITH MIXING RATIOS EXCEEDING 4 G/KG. LITTLE DOUBT SYSTEM
HAS ALL THE EARMARKS TO BE A RATHER SUBSTANTIAL PRECIP PRODUCER...
ALTHOUGH EXACTLY WHAT TYPE THAT PRECIP TAKES REMAINS A FORMIDABLE
CHALLENGE. WILL USE ROCK-STEADY ECMWF DEPICTIONS FOR THERMAL FIELDS.
THIS CONTINUES TO SUGGEST MAINLY SNOW AT THE ONSET EARLY
SATURDAY...RAPIDLY CHANGING OVER TO LIQUID FROM SOUTHWEST TO
NORTHEAST ACROSS NORTHERN LOWER MICHIGAN DURING THE MORNING. COULD
SEE SOME MINOR SNOW ACCUMULATIONS...ON THE ORDER OF AN INCH OR
SO...ESPECIALLY ACROSS THE HIGHER TERRAIN AREAS. WILL NEED TO WATCH
FOR A PERIOD OF FREEZING RAIN AS WAA STRENGTHENS JUST OFF THE DECK.
THIS SHOULD BE SHORT-LIVED EVENT (IF IT OCCURS AT ALL) AND NOT
WORTHY OF A MENTION IN THE FORECAST. MUCH BIGGER PRECIP TYPE
CHALLENGE ACROSS EASTERN UPPER...WITH STRONG DYNAMICS POSSIBLY
OVERCOMING MARGINAL THERMAL PROFILES TO KEEP PRECIP MAINLY ALL
SNOW...ESPECIALLY ALONG AND NORTH OF M-28. MODEL QPF FIELDS SOMEWHAT
DISCONCERTING...WITH PROGS SUPPORTING A HALF INCH OR MORE OF LIQUID
EQUIVALENT PRECIP BY LATER SATURDAY NIGHT. HEAVIER AMOUNTS NO DOUBT
POSSIBLE GIVEN AMOUNT OF EARLIER MENTIONED DYNAMICS. SNOW RATIOS
WILL NOT BE GREAT...ESPECIALLY SATURDAY AFTERNOON...WHEN SURFACE
READINGS WILL LIKELY EXCEED FREEZING AND HIGH APRIL SUN ANGLE TAKES
HOLD. STILL...COULD EASILY SEE SEVERAL INCHES OF HEAVY WET SNOW
ACCUMULATION BY LATER SATURDAY NIGHT...WITH PERIODS OF HIGH
INTENSITY SNOWFALL. NO HEADLINES FORTHCOMING ON THIS SHIFT...BUT IF
ABOVE COMES TO FRUITION...COULD SEE ADVISORY LEVEL SNOW AMOUNTS FOR
AT LEAST PARTS OF EASTERN UPPER. STAY TUNED! SYSTEM WINDS DOWN
QUICKLY LATE SATURDAY NIGHT...LEAVING BEHIND A DRY SUNDAY AND SUNDAY
EVENING.
CONFIDENCE DROPS REMARKABLY HEADING THROUGH NEXT WORK WEEK...WITH
GUIDANCE STRUGGLING WITH KEY INTERACTIONS TALKED ABOUT IN THE LEAD
PARAGRAPH. PLENTY OF POTENTIAL FOR ADDITIONAL SIGNIFICANT
SYSTEMS...WITH SOME DECENT SUPPORT FOR ONE SUCH SYSTEM TO IMPACT OUR
AREA TO KICK OFF THE WEEK. EXACTLY HOW FAR NORTH THIS SYSTEM RIDES UP
THROUGH THE OHIO VALLEY/SOUTHERN LAKES STILL FAR FROM BEING
DETERMINED. DEPENDING ON SUCH...MAY SEE ENOUGH COLD AIR ALONG THE
NORTHERN PERIPHERY OF ITS PRECIP SHIELD TO SUPPORT SOME WINTRY
WEATHER. NO NEED TO GET TOO SPECIFIC...AND WILL BE FORCED TO RUN
WITH A GUIDANCE CONSENSUS BLEND UNTIL A MORE DETERMINISTIC APPROACH
CAN BE UTILIZED. SAME STORY HEADING THROUGH THE REMAINDER OF THE
WEEK...WITH AGAIN THE POTENTIAL FOR ANOTHER WAVE TO ROTATE NORTHEAST
OUT OF THE SOUTHERN PLAINS. TIMING AND PLACEMENT OF SUCH ALL OVER
THE BOARD...AS IT WILL LIKELY REMAIN WITH BAROCLINIC AXIS SUBJECT TO
MANY CHANGES PER CANADIAN TROUGHING AND PASSAGE OF EARLIER IN THE
WEEK SYSTEMS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 156 PM EDT THU APR 4 2013
VFR CIGS AND VSBY IN ADVANCE OF A FRONTAL BOUNDARY DROPPING SOUTH ACRS
NRN LWR MI...WILL TREND MVFR AND OCCASIONALLY IFR IN MIXED RAIN
AND SNOW THROUGH BTWN 00Z AND 03Z. COLDER AIR AND NORTHWEST WINDS
ON THE BACK SIDE OF THE EXITING SYSTEM...WILL GENERATE SOME LAKE
SNOWS OVER TAF SITE KTVC AND KMBL FRIDAY. GUSTY SOUTHWEST WINDS IN
ADVANCE OF THE BOUNDARY...WILL TREND NORTHWEST ACRS NRN LWR MI TAF
SITES BTWN 00Z AND 06Z.
&&
.MARINE...
ISSUED AT 344 PM EDT THU APR 4 2013
GUSTY SOUTHWEST WINDS IN ADVANCE OF A FRONTAL BOUNDARY DROPPING
SOUTH OVER NRN MI...WILL TURN NORTHWEST OVERNIGHT AND REMAIN BREEZY
ON THE BACKSIDE OF THE EXITING BOUNDARY. RAIN/SNOW MIXED PCPN WILL
AFFECT NRN MI NEARSHORE WATERS THIS EVENING AS BOUNDARY DROPS
SOUTH...WITH SOME LAKE SNOWS POSSIBLE FRIDAY BEHIND THE FRONT.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR LHZ345>349.
LM...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR LMZ323-345-
346.
GALE WARNING UNTIL 8 PM EDT THIS EVENING FOR LMZ341-342-344.
LS...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR LSZ321-322.
&&
$$
SYNOPSIS...KAB
SHORT TERM...SWR
LONG TERM...MSB
AVIATION...SWR
MARINE...SWR
AREA FORECAST DISCUSSION
NWS GAYLORD MI
158 PM EDT THU APR 4 2013
.SYNOPSIS...
ISSUED AT 420 AM EDT THU APR 4 2013
A COLD FRONT WILL MOVE THROUGH NORTHERN MICHIGAN TODAY.
PRECIPITATION ASSOCIATED WITH THIS FRONT WILL START AS SNOW THIS
MORNING...BUT MIX WITH RAIN AS THE TEMPERATURES RISE ABOVE
FREEZING TODAY. THE RAIN WILL END IN THE AFTERNOON AS DRIER TAKES
OVER BEFORE THE FRONT MOVES THROUGH. HIGH PRESSURE AND COOLER
TEMPERATURES WILL SETTLE IN FOR THURSDAY NIGHT AND FRIDAY BEFORE A
STORM SYSTEM MOVES INTO NORTHERN MICHIGAN AND HANGS AROUND FOR
MUCH OF THE WEEKEND...BRINGING RAIN AND SNOW MIXED FOR SATURDAY
AND SUNDAY.
&&
.UPDATE...
ISSUED AT 156 PM EDT THU APR 4 2013
THE CURRENT FORECAST IS IN LINE...AS A FRONTAL BOUNDARY CONTINUES
TO DROP SOUTH ACRS NRN LWR MI.
UPDATE ISSUED AT 933 AM EDT THU APR 4 2013
CURRENT RADAR AND SFC OBS SHOWING AREA OF PCPN OVER ERN UPPER AND
STRAITS REGION...WHICH IS IN RESPONSE TO A COLD FRONT PUSHING INTO
THE WRN LAKES. PCPN ASSOCIATED WITH THIS FRONT SO FAR THIS MORNING
HAS BEEN CONFINED TO A NARROW BAND...HINDERED GREATLY BY LIMITED
MSTR. SFC DEW PTS SOUTH OF THE STRAITS ARE CURRENTLY IN THE
TEENS...THOUGH DEW PTS HAVE INCREASED INTO THE LOWER AND MID 20 OVER
ERN UPPER JUST IN ADVANCE OF THE FRONT.
AS FOR THE REST OF TODAY...LIMITED MSTR WILL REMAIN A HINDRANCE
THROUGH THE AFTERNOON OVR NRN LWR MI...KEEPING ANY PCPN CONFINED TO
A NARROW AREA RIGHT ALONG THE FRONT. MODEL SOUNDINGS SHOW PCPN CHCS
ENDING FROM GLR NORTH BTWN 18Z AND 21Z...AND ENDING NEAR SAGINAW BAY
REGION BETWEEN 00Z AND 03Z.
OVERALL CURRENT FCST IN LINE WITH MILD TEMP AND SUN EARLY OVER THE
SRN CWA...WITH PCPN ENDING OVER ERN UPPER EARLY THIS AFTN.
UPDATE ISSUED AT 607 AM EDT THU APR 4 2013
CHANGES THIS HOUR: HAVE CONTINUED SLOWING TREND OF POPS THROUGH
MUCH OF TODAY GIVEN RECENT GOOD AGREEMENT BETWEEN THE NAM/RAP/HRRR
GIVEN VERY IMPRESSIVE PERFORMANCE FROM THE RAP OVER THE PAST FEW
HOURS. SNOWFALL HAS ARRIVED FROM SAW-ERY-ANJ AND WILL GO AHEAD AND
BUMP UP NEAR TERM POPS TO CATEGORICAL FOR NORTHERN CHIPPEWA
THROUGH DAYBREAK. BEYOND THIS...INITIAL SURGE OF ISENTROPIC ASCENT
ALONG LLEVEL MOISTURE AXIS WILL SHIFT EAST AND WE/LL THEN AWAIT
FURTHER DEVELOPMENT ALONG THE FRONTAL BOUNDARY ITSELF...WHICH IS
NOW SLIDING SOUTHEAST THROUGH WESTERN UPPER. DON/T EXPECT THIS TO
BE SUBSTANTIAL...AND AS PREVIOUSLY MENTIONED...EXPECT IT TO
DWINDLE AS IT HEADS SOUTH...WITH RAIN GRADUALLY TAKING OVER AS THE
PREDOMINATE PRECIPITATION TYPE.
COULD SEE AN INCH OF MORNING ACCUMS FROM PARADISE TO ANJ /WEBCAMS
SHOW A COATING ATTM/...SO WATCH OUT FOR SOME SLICK AM TRAVEL IN
THESE SPOTS.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 420 AM EDT THU APR 4 2013
HIGH IMPACT WEATHER POTENTIAL: GALE FORCE WINDS OVER MUCH OF
NORTHERN LAKE MICHIGAN THROUGH MID MORNING. WILL LIKELY HAVE SOME
COASTAL WIND GUSTS ABOVE 30 MPH TODAY...OTHERWISE...NO HIGH
IMPACT WEATHER EXPECTED.
OVERVIEW: SURFACE MAP EARLY THIS MORNING REVEALS HIGH PRESSURE
RESPONSIBLE FOR THE BEAUTIFUL /ALBEIT CHILLY/ AFTERNOON YESTERDAY
HAVING PUSHED SOUTH AND EAST INTO THE OHIO VALLEY/MID ATLANTIC
REGION...THIS HAS ALLOWED BROAD SOUTHWESTERLY FLOW TO DEVELOP BETWEEN
THIS FEATURE AND RATHER IMPRESSIVE SURFACE LOW NOW TRAVELING FROM
WEST TO EAST ACROSS NORTHERN ONTARIO. PRIMARY FEATURE OF NOTE
THROUGH THE SHORT TERM PORTION OF THE FORECAST IS A COLD FRONT
DRAPED TO THE SOUTH AND WEST OF THIS LOW...APPROACHING LAKE SUPERIOR
AS OF THIS WRITING. STRENGTHENING SOUTHWESTERLY WINDS OVER NORTHERN
MICHIGAN HAVE PRECLUDED STEEP TEMPERATURE FALLS OVERNIGHT WITH MOST
LOCATIONS AT LEAST 10F WARMER THAN 24 HOURS AGO. LLEVEL MOISTURE
HAS NOT RESPONDED IN TANDEM...WITH 00Z APX RAOB SHOWING A PALTRY
0.14" PWAT. CLOSER TO THE FRONT...HOWEVER...PRECIPITATION ECHOES
HAVE BEEN BLOSSOMING OVER THE PAST COUPLE OF HOURS AS ROBUST LOW
LEVEL JET AT H8 /50KTS+/ TRANSPORTS A PLUME OF 2/3" PWATS RAPIDLY
EASTWARD.
THROUGH DAYBREAK: WINDS CONTINUE TO RAMP UP FROM WEST TO EAST...WITH
SLOWLY INCREASING MID AND UPPER LEVEL CLOUDINESS...PRIMARILY FROM THE
STRAITS NORTH. TIMING AREA OF INCREASING RADAR ECHOES SUGGESTS
PRECIPITATION COULD ARRIVE AS EARLY AS 5-6AM OVER EASTERN UPPER AS
SOME SNOW SHOWERS. INTERESTING TO NOTE SURFACE DEWPOINT TREND OVER
THE PAST FEW HOURS OVER NORTHERN LOWER...WITH VALUES PLUMMETING TO
BELOW 10F AT TVC/CAD AND ROPPING EVERYWHERE AWAY FROM LAKE
MICHIGAN. THIS SUGGESTS THE SLOWING TREND IN FRONTAL PRECIP
ARRIVAL /SEEN IN RECENT RENDTIONS OF THE HRRR/RAP/ ARE LIKELY ON
THE RIGHT TRACK.
TODAY: COLD FRONT PUSHES THROUGH NORTHERN MICHIGAN TODAY...STARTING
THE DAY OVER WESTERN UPPER AND REACHING MY SOUTHEASTERN ZONES BY
EVENING. PRIMARY CONCERNS TODAY CENTER AROUND PRECIPITATION
CHANCES AS THIS BOUNDARY MOVES THROUGH...AS WELL AS THE STRENGTH
OF SOUTHWESTERLY WINDS AHEAD OF IT.
TRAJECTORY ANALYSIS SHOWS LLEVEL SOURCE REGION FOR AIR OVER NORTHERN
LOWER TODAY COMES FROM THE IOWA/ILLINOIS REGION 24 HOURS AGO...AN
AREA FEATURING A DEARTH OF LLEVEL MOISTURE. SO...BOUNDARY WILL BE
FIGHTING INCREASINGLY DRY ATMOSPHERE AS IT PUSHES SOUTH AND EAST
WITH LLEVEL MOISTURE TONGUE THINNING. LLEVEL CONVERGENCE IS
MODEST...BUT WILL HAVE SOME HELP FROM AN ARRIVING JET MAX /AND ITS
ASSOCIATED RIGHT ENTRANCE REGION/ AS WELL AS CONTINUED ISENTROPIC
ASCENT. NET RESULT: EXPECT A BROKEN LINE OF SHOWERS TO SINK SOUTH
DURING THE DAY...WEAKENING AS THEY DO SO. RECENT MODEL TRENDS HAVE
CONTINUED TO SLOW THE SOUTHWARD MOVEMENT OF ANY PRECIPITATION...
AND WHILE THIS FORECAST REPRESENTS A SLOWING TREND...IT COULD
REQUIRE FURTHER SLOWING WITH PRECIITATION POTENTIALLY COMPLETELY
FALLING APART BEFORE MAKING IT MUCH SOUTH OF M-32.
PTYPE: STARTS THE DAY ALL SNOW...BUT RAPIDLY WARMING SURFACE LAYER
SUGGESTS PREDOMINATE TYPE TO SWITCH TO RAIN COASTAL LOCALES BY LATE
MORNING AND ALL AREAS BY AFTERNOON. ONLY CAVEAT TO THIS WILL BE
OVER THE INTERIOR HIGH SPOTS WHERE WET BULBS IN THE MID 30S INDICATE
A FEW SNOWFLAKES MIGHT MIX IN AT ANY TIME...ESP IF PRECIPITATION
RATES ARE DECENT. OVERALL VERY LITTLE IMPACT EXPECTED...HOWEVER...
OUTSIDE OF A FEW SLICK SPOTS TO START THE DAY FROM THE BRIDGE
NORTH. PAVEMENT TEMPS WILL BE TOO WARM TO SUPPORT ANY ICING BY MID
MORNING OVER NORTHERN LOWER.
WINDS: PRETTY MUCH FULLY FORCED BY THE STRENGTH OF THE LOW LEVEL
JET /40-50KTS AT H9 EARLY...WEAKENING AS IT HEADS SOUTH/ AND THE
AMOUNT OF MIXING WE CAN DEVELOP AHEAD OF THE BOUNDARY. GIVEN A
SOMEWHAT SLOWER ARRIVAL TO THE BOUNDARY...MIXING HEIGHTS SHOULD GET
A CHANCE TO BUILD EARLY...WITH MOMENTUM TRANSPORT SUGGESTING WE CAN
LIKELY TAP 30KTS. SO...EXPECT SOUTHWEST WINDS 15-25 MPH WITH GUSTS
OVER 30 MPH BY LATE MORNING AND THROUGH THE AFTERNOON OVER
NORTHERN LOWER...A LITTLE WEAKER THAN THIS FURTHER NORTH.
TEMPS: T9 ROCKETS TO JUST ABOVE FREEZING AHEAD OF THE BOUNDARY...
WITH THE POTENTIAL TO PRODUCE LOW-MID 50S AHEAD OF THE BOUNDARY.
COMPLICATING THIS WILL BE CLOUDS AND PRECIP...WHICH...WITH PRETTY
SUBSTANTIAL LLEVEL DEWPOINT DEPRESSIONS SUGGESTS AMPLE OPPORTUNITY
FOR EVAPORATIONAL COOLING. WILL ALLOW SOUTHEASTERN ZONES TO MAKE A
RUN AT 55...WITH LOCALES NORTH OF THIS GENERALLY IN THE MID-UPPER
40S.
TONIGHT: NORTHWEST WINDS WILL USHER COLDER AIR INTO THE REGION AS
HIGH PRESSURE BUILDS IN FROM THE NORTHERN PLAINS. T8 FALLS TO -12C
SOUTH/-15C NORTH AFTER MIDNIGHT...WHICH WITH A MINOR AMOUNT OF
RESIDUAL 850-700MB MOISTURE SUGGESTS THAT SOME LAKE RESPONSE MAY TRY
AND GET GOING...BUT NOT UNTIL THE VERY END OF THIS PERIOD. WILL
CARRY CHANCE POPS AFTER 09Z BUT NO SIGNIFICANT SNOWFALL EXPECTED.
TEMPERATURES LOOK TO FALL INTO THE MID 20S AS COLD AIR ADVECTION IS
OFFSET SOMEWHAT BY RESIDUAL WINDS AND SOME LAKE CLOUDINESS /NORTH/.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 420 AM EDT THU APR 4 2013
FRIDAY...INITIALLY, THERE WILL BE SOME LIGHT SNOW AND FLURRIES IN E
UPPER, MAINLY NEAR WHITEFISH POINT AS THE 850 MB TEMPERATURES FALL
TO AROUND -14C WITH ABOUT 50% RH IN THE 850-700 MB LAYER. THIS WILL
BE MAINLY IN THE MORNING, BECAUSE AS THE HIGH PRESSURE BUILDS INTO
THE REGION MORE DRY AIR PUSHES INTO THE FORECAST AREA, AND THE 850
MB TEMPERATURES RISE ABOVE -12C BY 18Z. SO WILL GO WITH A DRY DAY
OVERALL.
FRIDAY NIGHT...THE WARM ADVECTION WING FROM THE NEXT SYSTEM BEGINS
TO MOVE INTO THE REGION, ESPECIALLY AFTER 06Z. THIS WILL BRING A
CHANCE OF SNOW BY 12Z IN THE WESTERN PART OF THE FORECAST AREA. THE
LOWER LEVEL MOISTURE WILL BE THE MAIN CONCERN AS THE POPS ARE DRAWN
ROUGHLY WHERE THE 850 MB MOISTURE IS ABOVE 50%. HOWEVER, THIS COULD
JUST AS EASILY BE NOTHING UNTIL THE DAY ON SATURDAY, IF THE ATMOSPHERE
DOESN`T SATURATE FAST ENOUGH.
SATURDAY...THE WARM FRONT MOVES NORTH A BIT, BUT FOR THE MOISTURE
PART ONCE IT GETS TO AROUND THE STRAITS, IT LOOKS LIKE IT TRAVELS
EAST, WITH THE SFC LOW FOLLOWING ALONG IT. THIS SETS UP SNOW IN E
UPPER, WHICH COULD HAVE LIGHT TO MODERATE AMOUNTS THROUGH THE DAY.
WOULD EXPECT A MIX, ESPECIALLY BETWEEN M-32 AND THE STRAITS AS THE
PROFILES ARE EITHER ON THE 0C LINE. SOUTH OF M-32, THINK THAT IT
WILL BE MAINLY RAIN. OVERNIGHT, THE WARMER AIR WITH BOTH MODELS,
GETS TO THE STRAITS, THE RAIN WILL LIKELY GET ALL THE WAY TO THE
STRAITS, AND WE`LL GET A MIX IN E UPPER. THE CONCERN, BASED ON THE
PROFILES OF BOTH MODELS, IS THAT WE WILL PARTIALLY MELT SOME OF
THE SNOW (TEMPERATURES IN THE PROFILE GET TO +2C AROUND 850 MB
THEN FALL TO OR BELOW 0C IN E UPPER). SO WILL GO WITH SNOW/RAIN OR
FREEZING RAIN MIX AT THIS POINT, AND KEEP IT MENTIONED IN HWOAPX.
THE COLD AIR MOVES INTO E UPPER AGAIN ONCE THE LOW MOVES EAST. SO
E UPPER WILL SEE A CHANGE OVER AGAIN BETWEEN 06Z AND 12Z.
EXTENDED (SUNDAY THROUGH WEDNESDAY)...SUNDAY, THE MODELS MOVE THE
LOW EAST OF THE REGION AND THE COLD AIR MOVES BACK. HOWEVER, THINGS
ARE DRY ENOUGH AND WARM ENOUGH, THAT LITTLE IF NO PRECIPITATION WILL
FALL. MONDAY, LOOKS LIKE ANOTHER WAVE FORMS ON THE FRONT THAT
STALLS IT, AND EVEN ALLOWS FOR SOME WARMING. SO WILL GO WITH
CHANCE OF RAIN IN N LOWER AND A MIX IN E UPPER. TUESDAY, THE LOW
NO LONGER MOVES OUT OF THE MID MISSISSIPPI VALLEY AS THE MODELS
FOCUS DEVELOPMENT ON THE CLOSED 500 MB LOW IN THE SOUTHWEST
STATES. THIS WOULD KEEP THE SFC LOW IN TX/OK REGION WITH A WARM
FRONT/SFC TROUGH THAT IS STALLED IN THE OHIO VALLEY. OVERNIGHT,
THE GFS BEGINS TO LIFT THE 500 MB LOW INTO THE NORTHERN BRANCH.
THE ECMWF LOOKS BETTER WITH THE SLOWER LIFTING OF THE WAVE KEEPING
THE RAIN AND THE WARM FRONT ALONG OR SOUTH OF THE OHIO VALLEY.
WEDNESDAY, THINKING THAT THE GFS IS TOO WET, DUE TO THE PHASING OF
THE SYSTEMS. WOULD BE MORE INCLINED TO GO WITH THE ECMWF IDEA WITH
THE HIGH SETTLING IN OVER THE GREAT LAKES. WHICH WOULD KEEP US
DRY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 156 PM EDT THU APR 4 2013
VFR CIGS AND VSBY IN ADVANCE OF A FRONTAL BOUNDARY DROPPING SOUTH ACRS
NRN LWR MI...WILL TREND MVFR AND OCCASIONALLY IFR IN MIXED RAIN
AND SNOW THROUGH BTWN 00Z AND 03Z. COLDER AIR AND NORTHWEST WINDS
ON THE BACK SIDE OF THE EXITING SYSTEM...WILL GENERATE SOME LAKE
SNOWS OVER TAF SITE KTVC AND KMBL FRIDAY. GUSTY SOUTHWEST WINDS IN
ADVANCE OF THE BOUNDARY...WILL TREND NORTHWEST ACRS NRN LWR MI TAF
SITES BTWN 00Z AND 06Z.
&&
.MARINE...
ISSUED AT 420 AM EDT THU APR 4 2013
SUMMARY: A COLD FRONT WILL PUSH THROUGH NORTHERN MICHIGAN TODAY WITH
GUSTY SOUTHWEST WINDS AHEAD OF IT SHIFTING NORTHWESTERLY BEHIND IT
THIS EVENING AS HIGH PRESSURE BUILDS INTO THE GREAT LAKES REGION.
HIGH PRESSURE WILL REMAIN IN CONTROL OF OUR WEATHER THROUGH FRIDAY
NIGHT.
HEADLINES: GALE WARNING THROUGH LATE MORNING STILL LOOKS GOOD OVER
PORTIONS OF NORTHERN LAKE MICHIGAN. ELSEWHERE...WILL EXPAND SMALL
CRAFTS TO ALL ZONES FOR TODAY GIVEN ROBUST WIND FIELD AHEAD OF
APPROACHING COLD FRONT. MARGINAL SMALL CRAFT CONDITIONS CONTINUE
THROUGH TONIGHT BEFORE A BREAK IN WIND/WAVE ACTIVITY IS EXPECTED
FRIDAY. NEXT STORM SYSTEM ARRIVES SATURDAY WITH A RENEWED PERIOD OF
SMALL CRAFTS LIKELY THROUGHOUT THE NEARSHORE WATERS OF NORTHERN
MICHIGAN.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR LHZ345>349.
LM...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR LMZ323-345-
346.
GALE WARNING UNTIL 8 PM EDT THIS EVENING FOR LMZ341-342-344.
LS...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR LSZ321-322.
&&
$$
UPDATE...SR
SYNOPSIS...JL
SHORT TERM...ARNOTT
LONG TERM...JL
AVIATION...SR
MARINE...ARNOTT
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
113 PM CDT THU APR 4 2013
.UPDATED FOR 18Z TAF DISCUSSION...
.UPDATE.../ISSUED 955 AM CDT THU APR 4 2013/
AN UPPER LEVEL LOW PRESSURE SYSTEM CURRENTLY LOCATED OVER THE
ARKLATEX REGION WILL TRACK EAST ACROSS NORTH CENTRAL MISSISSIPPI
TODAY. LOOKING AT THE LATEST HRRR MODEL...BEST RAIN CHANCES WILL
OCCUR FROM EASTERN ARKANSAS TO NORTHWEST TENNESSEE. HAVE ADJUSTED
POPS ACCORDINGLY. HAVE ALSO LOWERED HIGHS SLIGHTLY. EXPECT
TEMPERATURES TO REMAIN IN THE UPPER 40S FOR HIGHS FOR THE MOST
PART DUE TO THE CLOUDS AND RAIN. UPDATE WILL BE OUT SHORTLY.
KRM
DISCUSSION... /ISSUED 308 AM CDT THU APR 4 2013/
SKIES WERE CLOUDY ACROSS THE MIDSOUTH WITH A FEW AREAS OF LIGHT
RAIN ON RADAR. WINDS WERE NORTHEAST AROUND 5 MPH WITH TEMPERATURES
HOLDING IN THE MID AND UPPER 40S. ON SATELLITE AN UPPER LEVEL LOW
WAS CENTERED IN SOUTHWEST OKLAHOMA WITH LEADING EDGE OF ASSOCIATED
ENHANCED CLOUD COVER AND PRECIPITATION ENTERING WESTERN ARKANSAS.
FOR TODAY AND TONIGHT...ONE LAST DREARY DAY FOR THE MIDSOUTH IN
REGARDS TO RAIN AND UNSEASONABLY COLD TEMPERATURES. FORTUNATELY
THE MODELS SHOW THE AFOREMENTIONED LOW BECOMING AN OPEN WAVE...AND
BEGINNING TO FILL AS IT PASSES JUST TO OUR SOUTH THIS
EVENING. THUS...RAINFALL AMOUNTS WILL LIKELY REMAIN UNDER A
QUARTER OF AN INCH FOR MANY MIDSOUTHERNERS. TEMPERATURES WILL
STRUGGLE TO REACH 50F ACROSS THE NORTH AND MID 50S SOUTH. AS THE
LOW TRACKS INTO ALABAMA AND GEORGIA TONIGHT AN UPPER LEVEL RIDGE
OVER THE PLAINS WILL QUICKLY BUILD INTO THE AREA. THIS SHOULD IN TURN
ALLOW FOR FASTER CLEARING EARLY FRIDAY MORNING. WITH DRIER AIR
WILL PUSHING IN FROM MISSOURI TEMPERATURES WILL EASILY CLIMB INTO
THE MID 60S.
THE REAL START TO THE MIDSOUTH WARMING TREND HOWEVER WILL BEGIN ON
SATURDAY AS LOW LEVEL WINDS TURN SOUTHERLY. SKIES THOUGH...MAY
BECOME PARTLY SUNNY THROUGHOUT THE DAY AS MODEL CROSS SECTIONS
YIELD THICKENING CIRRUS CLOUDS EXTENDING WELL EAST OF THE ROCKIES.
TEMPERATURES SHOULD STILL MANAGE TO MAKE IT INTO THE LOW AND MID 70S.
GULF MOISTURE WILL BEGIN TO SURGE NORTHWARD SATURDAY NIGHT AND SUNDAY
AS A COLD FRONT BECOMES STALLED ACROSS THE CORN BELT AND CENTRAL
PLAINS. WAA WILL CONTINUE ON SUNDAY DEVELOPING A DEEP LAYER CAP
BETWEEN 850 AND 700MB. THUS ANY ISOLATED CONVECTION FORMING WEST
OF THE MISSISSIPPI RIVER WILL EITHER WAA SHOWERS OR ELEVATED THUNDER.
HIGHS ON SUNDAY WILL REMAIN IN THE 70S WITH MILDER LOWS IN THE
MID AND UPPER 50S.
MONDAY THROUGH WEDNESDAY NIGHT...THIS PERIOD WILL SEE AN INCREASE
THREAT FOR STORMS AND SEVERE WEATHER AS A NEW STORM DEEPENS OVER
THE CENTRAL ROCKIES. THE UPPER FLOW OVER THE MIDSOUTH WILL BACK
FROM THE SOUTHWEST WITH SPEEDS INCREASING. THE COMBINATION OF
MINOR WAVES IN THE FLOW RIDING OVER THE STALLED BOUNDARY TO OUR
NORTH AND DEWPOINTS INCREASING TO THE MID AND UPPER 60S...WILL
WEAKEN THE ESTABLISHED CAP ALLOWING FOR SFC BASED CONVECTION. THE
GFS AND EURO BOTH SPORT 1500+ J/KG OF CAPE...7.0C+ LAPSE
RATES...AND LIFTED INDICES OF NEAR -6C. THE GFS ALSO IS INDICATING
0-1KM HELICITY VALUES IN EXCESS OF 3.0 M^2/S^2 INDICATING ROTATING
STORMS. SINCE MODEL RUNS OVER THE PAST THREE DAYS HAVE BEEN
CONSISTENT IN THE THREAT FOR SEVERE WEATHER FOR TUESDAY...WILL
INTRODUCE THIS THREAT IN THE UPCOMING HWO.
DEPENDENT ON AMOUNT OF CUMULUS CLOUD COVER/CONVECTION...DAYTIME
HIGHS COULD WARM CLOSE TO 80F. SOUTH WINDS WILL ALSO INCREASE AND
GUST TO 30MPH ON TUESDAY AS A SURFACE WAVE DEEPENS IN WEST TEXAS.
THIS FEATURE IS PROGGED TO MOVE INTO THE OZARKS ON WEDNESDAY AND
MAY PROVIDE A SECOND DAY THREAT FOR SEVERE WEATHER OVER OUR AREA.
JAB
&&
.AVIATION...
LOW CEILINGS IN RA/DZ/BR WILL CONTINUE TO PLAGUE THE MIDSOUTH
AIRPORTS THROUGH TONIGHT. GIVEN THE STUBBORN NATURE OF THIS UPPER
LOW AND PERSISTENT MOISTURE...HAVE OPTED TO KEEP LOW CEILINGS
THROUGH 06Z AT KMEM...WITH EARLIER CLEARING AT KJBR. AFTER 06Z THE
UPPER LOW WILL SHIFT EAST OF THE REGION...ALLOWING SKIES TO
GRADUALLY CLEAR THROUGH 12Z TOMORROW.
SAK
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 48 42 66 49 / 80 40 0 0
MKL 48 39 65 43 / 80 50 0 0
JBR 49 39 66 44 / 80 30 0 0
TUP 49 43 65 43 / 60 50 10 0
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$