Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 03/30/14
AREA FORECAST DISCUSSION...UPDATED
NWS RENO NV
732 PM PDT SAT MAR 29 2014
.UPDATE...
WE`LL BE EXPIRING THE WIND ADVISORY FOR MONO CO AND THE LAKE WIND
ADVISORY FOR PYRAMID LAKE WITH THIS UPDATE. REST OF THE FORECAST
FOR ONGOING STORM TO REMAIN UNCHANGED AT THIS TIME.
WINDS SUBSIDING ALONG HWY 395 AS COLDER AIR WORKS INTO THE REGION.
GUSTS OF 30-40 MPH REMAIN LIKELY OVERNIGHT IN THESE AREAS BUT
BELOW ADVISORY LEVELS. SNOW IS POURING DOWN IN THE TAHOE BASIN
WITH MAJOR TRAVEL PROBLEMS OVER THE SIERRA PASSES. SNOW IS
DROPPING SOUTH INTO MONO CO, PERHAPS A COUPLE HOURS SLOWER THAN
EARLIER GUIDANCE HAD INDICATED. 23Z HRRR PICKED UP WELL ON TRENDS
WITH SNOW AND SHOW SNOW STARTING TO TAPER OFF IN THE TAHOE BASIN
BETWEEN 6-8Z. SPILLOVER INTO FAR WRN NV HAS BEEN HARD TO COME BY,
BUT RADAR TRENDS IN THE PAST HOUR SHOW A SOLID BAND OF HEAVIER
PRECIP WORKING INTO WRN NV THAT MAY FINALLY GET US A PERIOD OF
LOWER ELEVATION RAINS FOR RENO/CARSON CITY/MINDEN. SUSANVILLE ON
THE OTHER HAND WAS UNDER THE PRECIP BAND MUCH OF TODAY - WITH
NEARLY 2 INCHES OF RAIN. IMPRESSIVE.
UPDATED FORECAST PRODUCTS OUT SHORTLY. AM PLANNING ON ANOTHER
UPDATE AROUND 9-930 PM TO TAKE A FRESH LOOK AT PRECIP TRENDS. CS
&&
.PREVIOUS DISCUSSION... /ISSUED 308 PM PDT SAT MAR 29 2014/
SYNOPSIS...
RAIN AND SNOW WILL CONTINUE THROUGH TONIGHT AS A LATE SEASON
WINTER STORM MOVES ACROSS THE SIERRA. A COLDER STORM SYSTEM WILL
IMPACT THE REGION MONDAY AND TUESDAY WITH LIGHT SNOW POSSIBLE IN
LOWER ELEVATIONS. BELOW NORMAL TEMPERATURES ARE EXPECTED THROUGH
MUCH OF THE UPCOMING WEEK, WITH ANOTHER CHANCE OF RAIN AND SNOW
SHOWERS THURSDAY AND FRIDAY.
SHORT TERM...
PRECIPITATION CONTINUES TO INTENSIFY NEAR AND WEST OF THE SIERRA
CREST AS MAIN TROUGH APPROACHES THE CALIFORNIA COAST. UPPER LEVEL
JET WILL ALSO MOVE ONSHORE AND ENHANCE THE MOISTURE BAND. SNOW
LEVELS EAST OF THE SIERRA CREST NEAR TAHOE HAVE REMAINED NEAR
6500-7000 FEET BUT SHOULD DROP TO LAKE LEVEL BEFORE 5 PM. SNOWFALL
RATES OF 1-2 INCHES PER HOUR ARE LIKELY TO PERSIST A PERIOD OF 6-8
HOURS, AND TRAVEL IMPACTS WILL INCREASE THIS EVENING AS SNOW
BEGINS ACCUMULATING ON PAVED SURFACES. THEREFORE THE WARNING WILL
REMAIN IN PLACE. FARTHER NORTH INTO LASSEN COUNTY, ALTHOUGH SOME
SNOW HAS ALREADY ACCUMULATED ABOVE 5500 FEET, THE HEAVIER SNOW IS
ALSO EXPECTED TO END SOONER, SO THE ADVISORY SHOULD BE SUFFICIENT.
LOCALIZED SNOW SHOWER BANDS MAY CONTINUE LATER TONIGHT, DEPENDING
ON HOW MUCH CONVECTIVE ACTIVITY DEVELOPS IN NORTH CENTRAL CA
DURING THE NEXT FEW HOURS.
FOR MONO COUNTY, SNOW WILL INCREASE THIS EVENING, SPREADING
SOUTHWARD ALONG THE SIERRA AND PROBABLY REACHING THE MAMMOTH
LAKES VICINITY BY 8 PM. BEFORE THE SNOW ARRIVES, WINDY CONDITIONS
WILL CONTINUE, SO THE ADVISORY WILL BE EXTENDED FOR A FEW MORE
HOURS. SINCE ALL OF THE SNOW WILL FALL IN A COMPRESSED TIME
PERIOD AND THE BAND WILL BEGIN TO WEAKEN LATE TONIGHT, SNOW TOTALS
NEAR THE CREST MAY TOP OUT CLOSER TO 16 INCHES INSTEAD OF THE
ORIGINAL 20 INCH PROJECTION. HOWEVER, IMPACTS WILL STILL BE
SUFFICIENT TO KEEP THE WARNING IN PLACE TONIGHT.
FOR WESTERN NV, THE RAIN SHADOW HAS PERSISTED SO FAR THIS
AFTERNOON. HOWEVER, THE LAST FEW RUNS OF THE HRRR MODEL HAVE
INDICATED RAPID SPILLOVER INTO THE RENO-CARSON VICINITY BETWEEN 4
AND 5 PM, WITH UP TO 6 HOURS OF NEARLY STEADY RAIN THROUGH THIS
EVENING. IF THIS OCCURS, RAINFALL COULD STILL ADD UP TO BETWEEN
0.25 AND 0.50 INCH, WITH LOCALLY HIGHER AMOUNTS IN FOOTHILL
LOCATIONS. FOR AREAS SOUTH OF HIGHWAY 50, THE MAJORITY OF THE RAIN
WILL FALL DURING THE LATE EVENING AND OVERNIGHT HOURS. THE PRECIP
COULD END AS SNOW BELOW 5000 FEET, BUT LITTLE OR NO SNOW
ACCUMULATION IS EXPECTED IN VALLEYS. ABOVE 5000 FEET, A COUPLE
INCHES MAY ACCUMULATE, BUT SOME LOCALLY HIGHER AMOUNTS MAY FALL IN
DOUGLAS COUNTY AS THE COLD AIR ARRIVES IN CONJUNCTION WITH THE
ONGOING HEAVIER PRECIP BAND. THIS OCCURRED WITH ONE OF THE STORMS
EARLIER THIS SEASON SO THIS WOULD NEED TO BE MONITORED LATER
TONIGHT.
ALL GUIDANCE IS IN AGREEMENT FOR A RAPID DISSIPATION OF THE RAIN
AND SNOW BY EARLY SUNDAY MORNING. FOR SUNDAY, A FEW SHOWERS MAY
LINGER NEAR THE SIERRA AND IN WEST CENTRAL NV EAST OF HIGHWAY 95,
OTHERWISE MOSTLY CLOUDY AND DRY CONDITIONS WILL PREVAIL WITH
MODERATE WEST WINDS GUSTING TO 20-30 MPH IN THE AFTERNOON. MJD
A COLDER LOW PRESSURE WILL DROP ALONG THE WEST COAST EARLY NEXT
WEEK, BRINGING ADDITIONAL PRECIPITATION TO THE SIERRA AND WESTERN
NEVADA. THIS LOW WILL BRING VERY COLD AIR DOWN FROM THE GULF OF
ALASKA WITH 700MB NEAR -10C. SNOW LEVELS WILL FALL TO MOST VALLEY
FLOORS BY MONDAY NIGHT AND INTO TUESDAY MORNING.
THAT BEING SAID, THE LATEST MODEL RUNS OF THE GFS AND ECMWF HAVE
BACKED OFF ON PRECIPITATION AMOUNTS IN WESTERN NEVADA, LEADING TO
CONTINUED UNCERTAINTY AND LOW FORECASTER CONFIDENCE. THIS IS MAINLY
BECAUSE THE LOW IS TRYING TO SPLIT OFF TO THE SOUTH AND DRIVE THE
JET AND DYNAMICS WELL INTO SOUTHERN CA.
THE HIGHEST CHANCES FOR SNOW WILL REMAIN IN THE SIERRA LATE MONDAY
AS THE FIRST SHORTWAVE MOVES THROUGH NORTHERN CA. THE 500MB
SHORTWAVE LOOKS TO BECOME NEGATIVELY TILTED, WHICH IS IS NOT
NECESSARILY GOOD FOR SPILLOVER. BUT, WE SHOULD BE UNSTABLE ENOUGH
FOR SOME LIGHT SPILLOVER IF THE JET REMAINS SOUTH OF MONO COUNTY.
BY TUESDAY, LOW PRESSURE REMAINS OVER THE REGION WITH CONVECTIVE
SHOWERS DEVELOPING UNDER THE COLD POOL. INSTABILITY LOOKS FAIRLY
STRONG DUE TO THE INCREASED SOLAR HEATING. WE WILL NEED TO KEEP A
CLOSE EYE, BECAUSE A SURFACE LOW DEVELOPING OVER SOUTHERN NEVADA MAY
CREATE SOME LOW-LEVEL FORCING THAT COULD INCREASE PRECIPITATION
RATES IN THE EASTERN SIERRA AND WESTERN NEVADA. HOON
LONG TERM...WEDNESDAY THROUGH SATURDAY...
FORECAST REMAINS UNCERTAIN FOR THE SYSTEM AT THE END OF NEXT WEEK.
DETERMINISTIC SOLUTIONS HAVE LARGELY DIVERGED WITH THE GFS
PRESENTING A SPLIT SYSTEM WILL VERY LITTLE PRECIPITATION; THE EC
SHOWS A MORE CONSOLIDATED FRONT WITH LOW PRESSURE IN CENTRAL OREGON
AND DECENT PRECIP ALONG THE SIERRA. THEREFORE, VERY FEW ADJUSTMENTS
TO THE EXISTING FORECAST FAVORING A BLENDED APPROACH WITH 30-40%
CHANCE OF PRECIP ALONG THE SIERRA FROM THURSDAY INTO SATURDAY.
TEMPERATURES CONTINUE TO LOOK AROUND TO SLIGHTLY COOLER THAN
SEASONAL AVERAGES WITH MODEST COLD AIR ALOFT AT 700MB AND AMPLE
CLOUD COVER. HOPEFULLY SOLUTIONS WILL BEGIN TO CONVERGE OVER THE
NEXT DAY OR SO TO ALLOW FOR HIGHER DETAILS. BOYD
AVIATION...
A CHANGEOVER TO SNOW IS EXPECTED BY 00Z AROUND THE TAHOE BASIN,
WITH ABOUT 6-8 HOURS OF CIGS/VSBY BELOW LANDING MINIMUMS AT
KTVL/KTRK THIS EVENING AND INTO THE LATE NIGHT. FOR KMMH, THE
WORST CONDITIONS ARE LIKELY FROM 03Z-12Z FROM THIS SAME SNOW BAND.
CONDITIONS WILL IMPROVE SUNDAY MORNING ALTHOUGH SOME MVFR CIGS
COULD LINGER THROUGH MUCH OF THE DAY AS RESIDUAL MOISTURE REMAINS
IN PLACE.
FOR WESTERN NV INCLUDING KRNO-KCXP, RAIN WILL INCREASE AROUND 00Z,
PRODUCING MVFR CIGS/VSBY AT TIMES FOR 4-6 HOURS THIS EVENING. THIS
PRECIP MAY BRIEFLY END AS SNOW, BUT LITTLE OR NO SNOW ACCUMULATION
IS EXPECTED ON RUNWAYS. VFR CONDITIONS ARE EXPECTED SUNDAY
ALTHOUGH SOME MOUNTAIN OBSCURATIONS WILL REMAIN POSSIBLE DUE TO
RESIDUAL CLOUD COVER. MJD
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...WINTER STORM WARNING UNTIL 5 AM PDT SUNDAY NVZ002.
LAKE WIND ADVISORY UNTIL 8 PM PDT THIS EVENING FOR PYRAMID LAKE
IN NVZ004.
CA...WINTER WEATHER ADVISORY UNTIL 5 AM PDT SUNDAY ABOVE 5500 FEET
FOR CAZ071.
WIND ADVISORY UNTIL 8 PM PDT THIS EVENING CAZ073.
WINTER STORM WARNING UNTIL 5 AM PDT SUNDAY CAZ073.
WINTER STORM WARNING UNTIL 5 AM PDT SUNDAY CAZ072.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
1123 AM PDT FRI MAR 28 2014
.SYNOPSIS...SHOWERS WILL CONTINUE ACROSS THE NORTH BAY TODAY WITH
PARTLY CLOUDY SKIES FROM THE BAY AREA SOUTHWARD. RAIN WILL SLOWLY
INCREASE OVER THE NORTH BAY OVERNIGHT AND THEN SPREAD SOUTHWARD
THROUGH THE BAY AREA DURING THE DAY SATURDAY...REACHING THE
CENTRAL COAST BY SATURDAY AFTERNOON AND EVENING. DRY WEATHER
RETURNS SUNDAY AND THEN A STRONG COLD FRONT WILL ARRIVE MONDAY
WITH RAIN AND GUSTY WINDS. SHOWERS AND THUNDERSTORMS WILL BE
POSSIBLE ON TUESDAY...DRYING WEDNESDAY AND THEN MORE RAIN POSSIBLE
BY NEXT THURSDAY AND FRIDAY.
&&
.DISCUSSION...AS OF 9:13 AM PDT FRIDAY...SHOWERS CONTINUE ACROSS
THE NORTH BAY AT THIS HOUR WITH NONE OF THE MODELS CAPTURING THE
ACTIVITY...NOT EVEN THE HRRR AND RAP MODELS. FOR THE MOST PART
SHOWERS ARE LIGHT AND CONFINED TO THE HILLS AND COAST BUT MT ST
HELENA...MT TAMALPAIS AND WOODACRE HAVE ALL RECEIVED OVER THREE
TENTHS OF AN INCH IN THE LAST 12 HOURS. ANYWAY...WILL KEEP LIGHT
SHOWERS GOING THROUGH THE DAY IN THE NORTH BAY WITH DRY WEATHER
FROM SAN FRANCISCO SOUTHWARD.
WARM FRONTAL BOUNDARY WILL BECOME MORE ORGANIZED BY THIS EVENING
IN THE VICINITY OF CAPE MENDOCINO WITH SHOWERS BECOMING STEADY
RAIN OVER THE NORTH BAY TONIGHT. LIGHT SOUTH/SOUTHWEST FLOW WILL
CREATE FAVORABLE UPSLOPE AS THE FRONT DRIFTS SOUTHWARD INTO THE
BAY AREA BY SUNRISE SATURDAY MORNING. FOR THE MOST PART IT LOOKS
LIKE A GENTLE...SOAKING RAIN WITH FAIRLY LIGHT WINDS. LATEST QPF
SHOWS 1-2 INCHES FOR THE WETTEST COASTAL HILLS WITH 0.25-0.75 FOR
THE VALLEYS...DRIER OF COURSE IN THE USUAL RAIN SHADOWED INLAND
VALLEYS. LATEST NAM MODEL SHOWS THINGS DRYING OUT IN THE NORTH BAY
BY SATURDAY AFTERNOON WHILE RAIN CONTINUES FOR MUCH OF THE DAY
THROUGHOUT THE BAY AREA WITH THE HEAVIEST RAINS REACHING THE
MONTEREY BAY REGION BY THE LATE AFTERNOON AND EARLY EVENING HOURS.
THE FRONT WILL BE FAIRLY SLOW MOVING AS IT PASSES THROUGH OUR CWA
BUT THEN QUICKLY EXIT THE REGION SATURDAY NIGHT LEAVING DRY
WEATHER IN ITS WAKE FOR SUNDAY.
ATTENTION WILL THEN TURN TO POTENTIALLY STRONGER SYSTEM THAT WILL
ARRIVE MONDAY. LATEST TIMING BRINGS RAIN INTO THE NORTH BAY BEFORE
NOON ON MONDAY AND THEN STEADY RAINS PASSING THROUGH THE BAY AREA
FOR THE MONDAY AFTERNOON COMMUTE. RAINS ASSOCIATED WITH THE
FRONTAL PASSAGE SHOULD BRIEFLY BE HEAVY WITH STRONG AND WELL
DEFINED COLD FRONTAL BOUNDARY. STEADY RAIN WILL TURN TO SHOWERS BY
MONDAY EVENING. HOWEVER THE CORE OF THE UPPER LOW WILL KEEP
NUMEROUS SHOWERS AND MAYBE EVEN THUNDERSTORMS GOING FOR MUCH OF
TUESDAY WITH FAVORABLE NORTHWESTERLY POST-FRONTAL SET-UP. EARLY
QPF ESTIMATES WITH MONDAY/TUESDAY SYSTEM SUGGESTS 0.50-1.00 FOR
THE VALLEYS AND 2 INCHES FOR THE HILLS.
A BREAK IN THE WEATHER ON WEDS WITH MORE RAIN CHANCES BY NEXT
THURSDAY AND FRIDAY. WILL BE UPDATING THE GRIDS WITH THE LATEST
THINKING FOR THE AFTERNOON PACKAGES.
&&
.AVIATION...AS OF 11:05 AM PDT FRIDAY...DOPPLER RADAR SHOWS RAIN
SHOWERS CONTINUE TO MOVE ACROSS THE NORTH BAY THIS MORNING.
SHOWERS WILL TAPER THIS AFTERNOON BEFORE THE NEXT WAVE OF RAIN
HITS THE AREA SATURDAY. MID AND UPPER LEVEL CLOUDS WILL CONTINUE
TO STREAM IN ACROSS THE REGION AHEAD OF THE APPROACHING COLD FRONT
WITH WINDS EXPECTED TO VEER INCREASINGLY TO THE SOUTH AS THE DAY
PROGRESSES. RAIN IS ANTICIPATED TO BEGIN IN THE NORTH BAY AFTER
MIDNIGHT TONIGHT...SPREADING SOUTH ACROSS THE REGION THROUGH THE
MORNING. MODERATE CONFIDENCE.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...VFR...GENERALLY LIGHT SOUTHERLY
WINDS ARE EXPECTED TO PREVAIL THOUGH MUCH OF THE FORECAST PERIOD.
WINDS WILL BECOME SOUTHWESTERLY BY EARLY AFTERNOON AS THE COLD
FRONT GETS CLOSER TO THE COAST. MODERATE CONFIDENCE.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...NONE.
$$
PUBLIC FORECAST: RWW
AVIATION: CW
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT:
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WWW.YOUTUBE.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
913 AM PDT FRI MAR 28 2014
.SYNOPSIS...SHOWERS WILL CONTINUE ACROSS THE NORTH BAY TODAY WITH
PARTLY CLOUDY SKIES FROM THE BAY AREA SOUTHWARD. RAIN WILL SLOWLY
INCREASE OVER THE NORTH BAY OVERNIGHT AND THEN SPREAD SOUTHWARD
THROUGH THE BAY AREA DURING THE DAY SATURDAY...REACHING THE
CENTRAL COAST BY SATURDAY AFTERNOON AND EVENING. DRY WEATHER
RETURNS SUNDAY AND THEN A STRONG COLD FRONT WILL ARRIVE MONDAY
WITH RAIN AND GUSTY WINDS. SHOWERS AND THUNDERSTORMS WILL BE
POSSIBLE ON TUESDAY...DRYING WEDNESDAY AND THEN MORE RAIN POSSIBLE
BY NEXT THURSDAY AND FRIDAY.
&&
.DISCUSSION...AS OF 9:13 AM PDT FRIDAY...SHOWERS CONTINUE ACROSS
THE NORTH BAY AT THIS HOUR WITH NONE OF THE MODELS CAPTURING THE
ACTIVITY...NOT EVEN THE HRRR AND RAP MODELS. FOR THE MOST PART
SHOWERS ARE LIGHT AND CONFINED TO THE HILLS AND COAST BUT MT ST
HELENA...MT TAMALPAIS AND WOODACRE HAVE ALL RECEIVED OVER THREE
TENTHS OF AN INCH IN THE LAST 12 HOURS. ANYWAY...WILL KEEP LIGHT
SHOWERS GOING THROUGH THE DAY IN THE NORTH BAY WITH DRY WEATHER
FROM SAN FRANCISCO SOUTHWARD.
WARM FRONTAL BOUNDARY WILL BECOME MORE ORGANIZED BY THIS EVENING
IN THE VICINITY OF CAPE MENDOCINO WITH SHOWERS BECOMING STEADY
RAIN OVER THE NORTH BAY TONIGHT. LIGHT SOUTH/SOUTHWEST FLOW WILL
CREATE FAVORABLE UPSLOPE AS THE FRONT DRIFTS SOUTHWARD INTO THE
BAY AREA BY SUNRISE SATURDAY MORNING. FOR THE MOST PART IT LOOKS
LIKE A GENTLE...SOAKING RAIN WITH FAIRLY LIGHT WINDS. LATEST QPF
SHOWS 1-2 INCHES FOR THE WETTEST COASTAL HILLS WITH 0.25-0.75 FOR
THE VALLEYS...DRIER OF COURSE IN THE USUAL RAIN SHADOWED INLAND
VALLEYS. LATEST NAM MODEL SHOWS THINGS DRYING OUT IN THE NORTH BAY
BY SATURDAY AFTERNOON WHILE RAIN CONTINUES FOR MUCH OF THE DAY
THROUGHOUT THE BAY AREA WITH THE HEAVIEST RAINS REACHING THE
MONTEREY BAY REGION BY THE LATE AFTERNOON AND EARLY EVENING HOURS.
THE FRONT WILL BE FAIRLY SLOW MOVING AS IT PASSES THROUGH OUR CWA
BUT THEN QUICKLY EXIT THE REGION SATURDAY NIGHT LEAVING DRY
WEATHER IN ITS WAKE FOR SUNDAY.
ATTENTION WILL THEN TURN TO POTENTIALLY STRONGER SYSTEM THAT WILL
ARRIVE MONDAY. LATEST TIMING BRINGS RAIN INTO THE NORTH BAY BEFORE
NOON ON MONDAY AND THEN STEADY RAINS PASSING THROUGH THE BAY AREA
FOR THE MONDAY AFTERNOON COMMUTE. RAINS ASSOCIATED WITH THE
FRONTAL PASSAGE SHOULD BRIEFLY BE HEAVY WITH STRONG AND WELL
DEFINED COLD FRONTAL BOUNDARY. STEADY RAIN WILL TURN TO SHOWERS BY
MONDAY EVENING. HOWEVER THE CORE OF THE UPPER LOW WILL KEEP
NUMEROUS SHOWERS AND MAYBE EVEN THUNDERSTORMS GOING FOR MUCH OF
TUESDAY WITH FAVORABLE NORTHWESTERLY POST-FRONTAL SET-UP. EARLY
QPF ESTIMATES WITH MONDAY/TUESDAY SYSTEM SUGGESTS 0.50-1.00 FOR
THE VALLEYS AND 2 INCHES FOR THE HILLS.
A BREAK IN THE WEATHER ON WEDS WITH MORE RAIN CHANCES BY NEXT
THURSDAY AND FRIDAY. WILL BE UPDATING THE GRIDS WITH THE LATEST
THINKING FOR THE AFTERNOON PACKAGES.
&&
.AVIATION...AS OF 4:40 AM PDT FRIDAY...A MIX OF SUN AND CLOUDS
WILL PASS OVER THE TERMINALS TODAY WITH A STRAY SHOWER POSSIBLE AS
A COLD FRONT APPROACHES THE CENTRAL CALIFORNIA COAST. SHOWERS ARE
EXPECTED IN THE SANTA ROSA AREA TODAY WITH RAIN HITTING THE SAN
FRANCISCO BAY AREA AFTER MIDNIGHT.
VICINITY OF KSFO...VFR...GENERALLY LIGHT SOUTHERLY WINDS ARE
EXPECTED TO PREVAIL THIS MORNING. WINDS WILL BECOME SOUTHWEST BY
EARLY AFTERNOON AS THE COLD FRONT GETS CLOSER TO THE COAST. A
PASSING SHOWER WILL BE POSSIBLE THIS MORNING WITH LIGHT RAIN
EXPECTED TO BEGIN AFTER MIDNIGHT. MODERATE CONFIDENCE.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...MVFR...GENERALLY LIGHT SOUTHERLY WINDS
ARE EXPECTED TO PREVAIL THIS MORNING. WINDS WILL BECOME SOUTHWESTERLY
BY EARLY AFTERNOON AS THE COLD FRONT GETS CLOSER TO THE COAST.
MODERATE CONFIDENCE.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...NONE.
$$
PUBLIC FORECAST: RWW
AVIATION: LARRY
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FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS EUREKA CA
906 AM PDT FRI MAR 28 2014
.SYNOPSIS...RAIN WILL CONTINUE TO SPREAD SOUTH TODAY AS AN
ATMOSPHERIC RIVER SLOWLY MOVES SOUTH OVER THE AREA. RAIN WILL
TAPER TO SHOWERS LATE TONIGHT AND BRING A SLIGHT CHANCE OF A
THUNDERSTORM AND SMALL HAIL ON SUNDAY.
&&
.UPDATE...RAIN HAS SPREAD SOUTH A BIT SLOWER THAN EXPECTED
TODAY...AT LEAST IN THE LOW ELEVATIONS. MODERATE TO THE HIGHER
ELEVATIONS HAVE BEEN GETTING SIGNIFICANT RAINFALL AS EXPECTED.
COOSKIE MOUNTAIN NEAR CAPE MENDOCINO HAS GOTTEN 1.40 INCHES AS OF
8 AM. RAIN IS STILL EXPECTED IN THE EUREKA AREA...BUT IT WILL
START A BIT LATER AND AMOUNTS WILL BE A LOWER THAN PREVIOUSLY
EXPECTED. MKK
&&
.PREV DISCUSSION......ISSUED AT 400 AM PDT...
SHORT TERM (TODAY THROUGH TUESDAY)...MADE SLIGHT ADJUSTMENTS TO THE
EARLY MORNING FORECAST TO SLOW THE SOUTHERN PROGRESSION OF THE FRONT
BY A COUPLE HOURS. THE ONLY NOTICEABLE CHANGE WILL BE FOR SOUTHERN
MENDOCINO COUNTY THIS MORNING. OTHERWISE LEFT THE FORECAST NEARLY
THE SAME FOR TODAYS RAIN. THE MAIN FORECAST MODELS, THE GFS AND NAM,
CONTINUE TO SHOW THE ONSET OF STEADY RAIN BETWEEN 12Z AND 18Z.
HOWEVER, THE SHORT TERM RUC HOLDS OFF THE ONSET UNTIL ABOUT 18Z TO
19Z. REGARDLESS, PERIODS OF LIGHT RAIN ARE EXPECTED AHEAD OF THE
FULL ONSET OF THE ATMOSPHERIC RIVER RAINS, SO HAVE LEFT THE 100 POPS
FOR THE EARLY MORNING HOURS. LOOKING AT THE GEFS IVT MEAN VS THE OP
GFS IVT FROM THE 12Z RUN YESTERDAY AND THERE APPEARS TO BE A BIT OF
WIGGLE ROOM IN THE EXACT LANDING OF THE AR HEAD. THE GEFS MEAN TAKES
THE BULK OF THE IVT INTO SRN ORE WHILE THE OP GFS BRINGS IT INTO FAR
NORTHERN CAL. CAN NOT FIND ENOUGH EVIDENCE TO LOWER QPF AMOUNTS, BUT
AS THE DAY GOES ON WE MAY NEED TO ADJUST THE QPF DOWNWARD SLIGHTLY.
THIS WILL DEPEND ON WHERE THE HEAD OF THE AR HITS. SNOW LEVELS
WILL REMAIN AROUND 6KFT TODAY WITH ONLY THE HIGHEST PEAKS
RECEIVING ANY SNOW.
THE COLD FRONT STEERING TODAYS AR WILL SLOWLY SINK TO THE SOUTH
THROUGH THE DAY AND OVERNIGHT. AN UNSTABLE COOL AIR MASS WITH
LOWERING HEIGHTS WILL FILL IN BEHIND THE FRONT. A POST FRONTAL
TROUGH WILL BRING INSTABILITY ASSOCIATED WITH A VORT MAX TO THE
REGION ON SATURDAY AS THE TROUGH APPROACHES. MODELS ARE SHOWING
INCREASING CAPE AND LOWERING LI`S WITH THIS VORT MAX. WITH FAIRLY
WARM AIR IN PLACE AT THE SURFACE AND COOLING AIR ALOFT, THE
INGREDIENTS SHOULD BE PRESENT FOR WIDESPREAD CONVECTIVE SHOWERS
ACROSS NWCA. THERE IS A SLIGHT CHANCE SOME OF THESE SHOWERS WILL BE
THUNDERSTORMS, PRODUCING SMALL HAIL AND LOCALLY GUSTY WINDS. THE NAM
IS SHOWING A THIN CAPE PROFILE FOR MUCH OF THE AREA ON SAT WITH
VALUES IN THE FEW HUNDRED J/KG. THE TOP OF THE CONVECTION COULD
REACH AS HIGH AS 22KFT WITH A TEMP OF -37C. THIS SHOULD PROVIDE
ENOUGH DEPTH TO PRODUCE SMALL HAIL. FOR THE FORECAST, WENT AHEAD AND
MATCHED THE NEIGHBORS AND EXPANDED THE SLIGHT CHANCE OF TSTMS ACROSS
THE ENTIRE CWA. SPC CONTINUES TO SHOW NWCA IN THE THUNDERLINE FOR
SAT.
SUNDAY BROUGHT SOME SIGNIFICANT CHANGES TO THE ONGOING FORECAST.
WENT AHEAD AND BIT OFF ON THE IDEA OF A DRY DAY. SO PULLED BACK POPS
TO SLIGHT CHANCE OR LESS. MONDAY HOWEVER I WENT THE OTHER WAY.
MODELS HAVE BEEN CONSISTENT WITH A DIGGING UPPER LOW DIVING INTO
CALIFORNIA AND BRING ANOTHER QUICK SHOT OF RAIN. CONFIDENCE IS
INCREASING FOR RAIN ON MONDAY, SO WENT AHEAD AND UPPED THE POPS TO
100 FOR A SHORT TIME. THIS DIGGING LOW COULD PROVE TO VERY
INTERESTING WITH SHARP COOLING ALOFT, A NEG TILTED TROUGH AXIS, AND
A STRONG VORT MAX. THIS COULD BRING NWCA ANOTHER SHOT OF TSTMS AND
SMALL HAIL ON MONDAY. THE OTHER ISSUE TO WATCH ON MONDAY WILL BE
LOWERING SNOW LEVELS AND WIDESPREAD PRECIPITATION. THIS COULD
BRING A FEW INCHES OF SNOW TO AREA PASSES BY MONDAY EVENING. MORE
TO COME. TUESDAY WILL BRING THE BEGINNING OF A SHORT BREAK IN
WEATHER. BFG
LONG TERM (WEDNESDAY THRU FRIDAY)...WED WILL CONTINUE A SHORT BREAK
IN THE WEATHER. MODELS ARE INDICATING ANOTHER UPPER TROUGH DIVING IN
FOR THE SECOND HALF OF THE WEEK, BUT ARE HAVING ISSUES WITH TIMING
STRENGTH. WITH A WET PATTERN EXPECTED, KEPT WITH THE IDEA OF LIKELY
RAIN FOR THU THROUGH SAT. CONFIDENCE IS LOW TO MODERATE DUE TO
UNCERTAINTY IN TIMING AND STRENGTH. BFG
AVIATION...BREEZY SOUTHERLY WINDS WILL ACCOMPANY PERIODS OF
HEAVY RAIN TODAY. EXPECT MVFR WITH PERIODS OF LIFR DURING HEAVY
RAIN ACROSS THE REGION.
MARINE...SOUTHERLY WINDS WILL PERSIST ACROSS THE WATERS THROUGH THE
MIDDLE OF NEXT WEEK. A SERIES OF LONG PERIOD WESTERLY SWELLS WILL
PROPAGATE ACROSS THE WATERS THROUGH THE MIDDLE OF NEXT WEEK. THE
WINDS AND SEAS WILL INCREASE TODAY AS A COLD FRONT APPROACHES THE
AREA. THE SEAS WILL REMAIN ELEVATED THROUGH THE MIDDLE OF NEXT
WEEK. SMALL CRAFT ADVISORIES ARE IN EFFECT ACROSS THE WATERS
THROUGH EARLY NEXT WEEK.
HYDROLOGY...
AN ATMOSPHERIC RIVER ACCOMPANIED BY A SLOW MOVING COLD FRONT WILL
BRING COPIOUS AMOUNTS OF RAINFALL TO NORTHWEST CALIFORNIA TODAY
THROUGH SATURDAY MORNING. STEADY RAIN AND OCCASIONAL PERIODS OF
HEAVY RAIN CAN BE EXPECTED AS THE FRONT MOVES ACROSS THE REGION.
THE HIGHER RAINFALL VALUES WILL OCCUR IN DEL NORTE COUNTY AND
ALONG THE COASTAL MOUNTAIN RANGES.
THE RAINFALL WILL BEGIN OVER DEL NORTE COUNTY THIS MORNING AND
MOVE SOUTH ACROSS HUMBOLDT AND TRINITY COUNTIES THROUGHOUT
FRIDAY AFTERNOON AND INTO MENDOCINO COUNTY FRIDAY EVENING.
POTENTIAL IMPACTS:
THE MAIN STEM RIVERS WILL HAVE RAPID RISES...BUT NO FLOODING IS
EXPECTED. ALL THE RIVERS ARE FORECAST TO REMAIN BELOW MONITOR
STAGE.
THE TRIBUTARY STREAMS WILL ALSO RISE BUT ARE EXPECTED TO
REMAIN WITHIN THEIR BANKS.
THERE IS THE POSSIBILITY OF URBAN FLOODING DUE TO CLOGGED STORM
DRAINS. AREAS WITH POOR DRAINAGE AND OTHER LOW LYING AREAS CAN
EXPECT PONDING OF WATER.
AFTER THE FRONT PASSES SCATTERED SHOWERS ARE EXPECTED THROUGHOUT
THE DAY SATURDAY.
FORECAST PRECIPITATION AMOUNTS:
VALID 500 AM FRIDAY TO 500 AM SATURDAY
SMITH RIVER BASIN...........3 TO 4 INCHES
KLAMATH RIVER BASIN.........2 TO 3 INCHES
REDWOOD CREEK BASIN.........2.5 TO 3.5 INCHES
TRINITY RIVER BASIN.........2 TO 3 INCHES
MAD RIVER BASIN.............2 TO 3 INCHES
VAN DUZEN RIVER BASIN.......2.5 TO 3.5INCHES
SF EEL RIVER BASIN..........2.5 TO 3.5 INCHES
EEL RIVER BASIN.............2 TO 3 INCHES
VALID FROM 1100 AM FRIDAY TO 1100 AM SATURDAY
NAVARRO RIVER BASIN.........2 TO 3 INCHES
RUSSIAN RIVER BASIN.........1.5 TO 2.5 INCHES
&&
.EKA WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
NORTHWEST CALIFORNIA COASTAL WATERS...SMALL CRAFT ADVISORY UNTIL 9 AM PDT SUNDAY PZZ450-455-475.
SMALL CRAFT ADVISORY UNTIL 4 PM PDT MONDAY PZZ470.
&&
$$
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AREA FORECAST DISCUSSION
NWS EUREKA CA
400 AM PDT FRI MAR 28 2014
.SYNOPSIS...A RAINY FRIDAY IS ON TAP FOR NW CALIFORNIA AS AN
ATMOSPHERIC RIVER SETS IN THIS MORNING. RAIN WILL TAPER TO SHOWERS
ON SATURDAY AND BRING A SLIGHT CHANCE OF A THUNDERSTORM AND SMALL
HAIL.
&&
.SHORT TERM (TODAY THROUGH TUESDAY)...MADE SLIGHT ADJUSTMENTS TO THE
EARLY MORNING FORECAST TO SLOW THE SOUTHERN PROGRESSION OF THE FRONT
BY A COUPLE HOURS. THE ONLY NOTICEABLE CHANGE WILL BE FOR SOUTHERN
MENDOCINO COUNTY THIS MORNING. OTHERWISE LEFT THE FORECAST NEARLY
THE SAME FOR TODAYS RAIN. THE MAIN FORECAST MODELS, THE GFS AND NAM,
CONTINUE TO SHOW THE ONSET OF STEADY RAIN BETWEEN 12Z AND 18Z.
HOWEVER, THE SHORT TERM RUC HOLDS OFF THE ONSET UNTIL ABOUT 18Z TO
19Z. REGARDLESS, PERIODS OF LIGHT RAIN ARE EXPECTED AHEAD OF THE
FULL ONSET OF THE ATMOSPHERIC RIVER RAINS, SO HAVE LEFT THE 100 POPS
FOR THE EARLY MORNING HOURS. LOOKING AT THE GEFS IVT MEAN VS THE OP
GFS IVT FROM THE 12Z RUN YESTERDAY AND THERE APPEARS TO BE A BIT OF
WIGGLE ROOM IN THE EXACT LANDING OF THE AR HEAD. THE GEFS MEAN TAKES
THE BULK OF THE IVT INTO SRN ORE WHILE THE OP GFS BRINGS IT INTO FAR
NORTHERN CAL. CAN NOT FIND ENOUGH EVIDENCE TO LOWER QPF AMOUNTS, BUT
AS THE DAY GOES ON WE MAY NEED TO ADJUST THE QPF DOWNWARD SLIGHTLY.
THIS WILL DEPEND ON WHERE THE HEAD OF THE AR HITS. SNOW LEVELS
WILL REMAIN AROUND 6KFT TODAY WITH ONLY THE HIGHEST PEAKS
RECEIVING ANY SNOW.
THE COLD FRONT STEERING TODAYS AR WILL SLOWLY SINK TO THE SOUTH
THROUGH THE DAY AND OVERNIGHT. AN UNSTABLE COOL AIR MASS WITH
LOWERING HEIGHTS WILL FILL IN BEHIND THE FRONT. A POST FRONTAL
TROUGH WILL BRING INSTABILITY ASSOCIATED WITH A VORT MAX TO THE
REGION ON SATURDAY AS THE TROUGH APPROACHES. MODELS ARE SHOWING
INCREASING CAPE AND LOWERING LI`S WITH THIS VORT MAX. WITH FAIRLY
WARM AIR IN PLACE AT THE SURFACE AND COOLING AIR ALOFT, THE
INGREDIENTS SHOULD BE PRESENT FOR WIDESPREAD CONVECTIVE SHOWERS
ACROSS NWCA. THERE IS A SLIGHT CHANCE SOME OF THESE SHOWERS WILL BE
THUNDERSTORMS, PRODUCING SMALL HAIL AND LOCALLY GUSTY WINDS. THE NAM
IS SHOWING A THIN CAPE PROFILE FOR MUCH OF THE AREA ON SAT WITH
VALUES IN THE FEW HUNDRED J/KG. THE TOP OF THE CONVECTION COULD
REACH AS HIGH AS 22KFT WITH A TEMP OF -37C. THIS SHOULD PROVIDE
ENOUGH DEPTH TO PRODUCE SMALL HAIL. FOR THE FORECAST, WENT AHEAD AND
MATCHED THE NEIGHBORS AND EXPANDED THE SLIGHT CHANCE OF TSTMS ACROSS
THE ENTIRE CWA. SPC CONTINUES TO SHOW NWCA IN THE THUNDERLINE FOR
SAT.
SUNDAY BROUGHT SOME SIGNIFICANT CHANGES TO THE ONGOING FORECAST.
WENT AHEAD AND BIT OFF ON THE IDEA OF A DRY DAY. SO PULLED BACK POPS
TO SLIGHT CHANCE OR LESS. MONDAY HOWEVER I WENT THE OTHER WAY.
MODELS HAVE BEEN CONSISTENT WITH A DIGGING UPPER LOW DIVING INTO
CALIFORNIA AND BRING ANOTHER QUICK SHOT OF RAIN. CONFIDENCE IS
INCREASING FOR RAIN ON MONDAY, SO WENT AHEAD AND UPPED THE POPS TO
100 FOR A SHORT TIME. THIS DIGGING LOW COULD PROVE TO VERY
INTERESTING WITH SHARP COOLING ALOFT, A NEG TILTED TROUGH AXIS, AND
A STRONG VORT MAX. THIS COULD BRING NWCA ANOTHER SHOT OF TSTMS AND
SMALL HAIL ON MONDAY. THE OTHER ISSUE TO WATCH ON MONDAY WILL BE
LOWERING SNOW LEVELS AND WIDESPREAD PRECIPITATION. THIS COULD
BRING A FEW INCHES OF SNOW TO AREA PASSES BY MONDAY EVENING. MORE
TO COME. TUESDAY WILL BRING THE BEGINNING OF A SHORT BREAK IN
WEATHER. BFG
.LONG TERM (WEDNESDAY THRU FRIDAY)...WED WILL CONTINUE A SHORT BREAK
IN THE WEATHER. MODELS ARE INDICATING ANOTHER UPPER TROUGH DIVING IN
FOR THE SECOND HALF OF THE WEEK, BUT ARE HAVING ISSUES WITH TIMING
STRENGTH. WITH A WET PATTERN EXPECTED, KEPT WITH THE IDEA OF LIKELY
RAIN FOR THU THROUGH SAT. CONFIDENCE IS LOW TO MODERATE DUE TO
UNCERTAINTY IN TIMING AND STRENGTH. BFG
&&
.AVIATION...BREEZY SOUTHERLY WINDS WILL ACCOMPANY PERIODS OF
HEAVY RAIN TODAY. EXPECT MVFR WITH PERIODS OF LIFR DURING HEAVY
RAIN ACROSS THE REGION.
&&
.MARINE...SOUTHERLY WINDS WILL PERSIST ACROSS THE WATERS THROUGH THE
MIDDLE OF NEXT WEEK. A SERIES OF LONG PERIOD WESTERLY SWELLS WILL
PROPAGATE ACROSS THE WATERS THROUGH THE MIDDLE OF NEXT WEEK. THE
WINDS AND SEAS WILL INCREASE TODAY AS A COLD FRONT APPROACHES THE
AREA. THE SEAS WILL REMAIN ELEVATED THROUGH THE MIDDLE OF NEXT
WEEK. SMALL CRAFT ADVISORIES ARE IN EFFECT ACROSS THE WATERS
THROUGH EARLY NEXT WEEK.
&&
.HYDROLOGY...
AN ATMOSPHERIC RIVER ACCOMPANIED BY A SLOW MOVING COLD FRONT WILL
BRING COPIOUS AMOUNTS OF RAINFALL TO NORTHWEST CALIFORNIA TODAY
THROUGH SATURDAY MORNING. STEADY RAIN AND OCCASIONAL PERIODS OF
HEAVY RAIN CAN BE EXPECTED AS THE FRONT MOVES ACROSS THE REGION.
THE HIGHER RAINFALL VALUES WILL OCCUR IN DEL NORTE COUNTY AND
ALONG THE COASTAL MOUNTAIN RANGES.
THE RAINFALL WILL BEGIN OVER DEL NORTE COUNTY THIS MORNING AND
MOVE SOUTH ACROSS HUMBOLDT AND TRINITY COUNTIES THROUGHOUT
FRIDAY AFTERNOON AND INTO MENDOCINO COUNTY FRIDAY EVENING.
POTENTIAL IMPACTS:
THE MAIN STEM RIVERS WILL HAVE RAPID RISES...BUT NO FLOODING IS
EXPECTED. ALL THE RIVERS ARE FORECAST TO REMAIN BELOW MONITOR
STAGE.
THE TRIBUTARY STREAMS WILL ALSO RISE BUT ARE EXPECTED TO
REMAIN WITHIN THEIR BANKS.
THERE IS THE POSSIBILITY OF URBAN FLOODING DUE TO CLOGGED STORM
DRAINS. AREAS WITH POOR DRAINAGE AND OTHER LOW LYING AREAS CAN
EXPECT PONDING OF WATER.
AFTER THE FRONT PASSES SCATTERED SHOWERS ARE EXPECTED THROUGHOUT
THE DAY SATURDAY.
FORECAST PRECIPITATION AMOUNTS:
VALID 500 AM FRIDAY TO 500 AM SATURDAY
SMITH RIVER BASIN...........3 TO 4 INCHES
KLAMATH RIVER BASIN.........2 TO 3 INCHES
REDWOOD CREEK BASIN.........2.5 TO 3.5 INCHES
TRINITY RIVER BASIN.........2 TO 3 INCHES
MAD RIVER BASIN.............2 TO 3 INCHES
VAN DUZEN RIVER BASIN.......2.5 TO 3.5INCHES
SF EEL RIVER BASIN..........2.5 TO 3.5 INCHES
EEL RIVER BASIN.............2 TO 3 INCHES
VALID FROM 1100 AM FRIDAY TO 1100 AM SATURDAY
NAVARRO RIVER BASIN.........2 TO 3 INCHES
RUSSIAN RIVER BASIN.........1.5 TO 2.5 INCHES
&&
.EKA WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
NORTHWEST CALIFORNIA COASTAL WATERS...SMALL CRAFT ADVISORY UNTIL 9 AM PDT SUNDAY PZZ450-455-475.
SMALL CRAFT ADVISORY UNTIL 4 PM PDT MONDAY PZZ470.
&&
$$
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AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1024 AM MDT FRI MAR 28 2014
.UPDATE...
&&
.SHORT TERM...MIXING HAS COMMENCED...ALLOWING FOR GUSTY WESTERLY
WINDS TO SPREAD OFF THE FOOTHILLS ONTO THE ADJACENT PLAINS. SOME
GUSTS AROUND 45 MPH OCCURRING ACROSS PORTIONS OF THE AREA.
MOUNTAIN WEB CAMS STILL INDICATING SOME LIGHT SNOW ALONG THE
CONTINENTAL DIVIDE OF SUMMIT AND GRAND COUNTIES. THERE MAY ALSO BE
SOME LIGHT SNOW ACROSS THE PARK AND GORE RANGES OF WESTERN JACKSON
COUNTY. OVERALL THE SNOW IS SHOWING SOME SIGNS OF DECREASING AS
SLIGHTLY DRIER AND MORE SUBSIDENT AIRMASS SPREADS ACROSS THE
AREA. FLOW ALOFT HAS BECOME MORE NORTHWEST BEHIND THE RECENT UPPER
TROUGH. LATEST MODEL CROSS SECTIONS SHOW MOISTURE DEPTH DECREASING
THROUGH THE DAY...WOULD EXPECT TO SEE A CONTINUED DECREASE IN
MOUNTAIN SNOW...THOUGH IT MAY BE A GRADUAL DECREASE DUE TO
PERSISTENT OROGRAPHICS. ANY ADDITIONAL ACCUMULATIONS TO BE
LIGHT...THOUGH SOME FAVORED WEST FACING AREAS COULD SEE UP TO AN
INCH OF ADDITIONAL SNOWFALL. CURRENT FORECASTS SHOW THIS
TREND...SO ONLY MINOR CHANGES EXPECTED. CURRENT WESTERLY WINDS TO
SHIFT TO THE NORTHWEST BY 18Z AS MIXING CONTINUES AND SURFACE
GRADIENT BECOMES NORTHWEST. LATEST RAP INDICATING MAX GUSTS
AROUND 45 MPH STILL A POSSIBILITY THROUGH THE AFTERNOON...
ESPECIALLY IN AND NEAR THE FOOTHILLS AND ALONG THE WYOMING BORDER.
WILL MAKE SOME MINOR ADJUSTMENTS TO WIND GRIDS. WINDS STILL
EXPECTED TO DECREASE THIS EVENING WITH WEAKENING GRADIENT. LATEST
MODELS SHOWING SOME POTENTIAL FOR A FEW SHOWERS ACROSS THE FAR
NORTHEAST PLAINS THIS AFTERNOON AS A BATCH OF MID LEVEL MOISTURE
SPREADS INTO THE AREA WITH THE NORTHWEST FLOW ALOFT. LATEST RAP
GENERATES LIGHT QPF IN NORTHEAST WELD...WESTERN LOGAN AND NORTHERN
WASHINGTON COUNTIES BETWEEN 21Z AND 00Z. DON`T SEE ANYTHING ON
SATELLITE UPSTREAM AT THIS TIME TO INDICATE SHOWERS COULD DEVELOP.
WILL KEEP THINGS DRY FOR NOW BUT WILL CONTINUE TO MONITOR FOR ANY
DEVELOPMENT.
.AVIATION...WESTERLY WINDS FINALLY SPREADING ACROSS THE AREA...
WITH KBJC ALREADY SHIFTING TO THE WEST NORTHWEST. AS MIXING
CONTINUES...SHOULD SEE WINDS AT KDEN AND KAPA INCREASING BECOMING
WEST NORTHWEST BY 18Z IN LINE WITH LATEST RAP AND HRRR. CURRENT
TAFS SHOW THIS TREND AND WILL CONTINUE FOR THE UPCOMING ISSUANCE.
SOME GUSTS TO AROUND 30 KTS STILL POSSIBLE BY 21Z. WINDS EXPECTED
TO DECREASE THIS EVENING...TRANSITIONING TO A DRAINAGE FLOW. VFR
TO PREVAIL WITH CEILINGS ABOVE 12000 FEET AGL.
&&
.PREV DISCUSSION... /ISSUED 436 AM MDT FRI MAR 28 2014/
SHORT TERM...A BAND OF MODERATE TO HEAVY SNOW CONTINUES TO TRACK
EAST AND SOUTHEAST OVER THE PLAINS...AND WILL BE MOVING THROUGH
WASHINGTON AND NORTHEAST ELBERT COUNTIES THROUGH 5 AM. HAVE
ALREADY ADJUSTED FORECAST FOR THIS SNOWFALL THROUGH SUNRISE AND
HAVE EXTENDED SOME LOW POPS FOR EARLY THIS AM OUT OVER THE EASTERN
BORDER OF CWA. ALREADY CLEARING SKIES FURTHER WEST TOWARDS THE
FRONT RANGE AS SUBSIDENCE STARTING TO KICK IN AS UPPER LEVEL TROF
MOVES OVER THE STATE WITH MAIN CIRCULATION NOTED OVER NORTHEAST
WYOMING. DRYING NOTED IN WATER VAPOR IMAGERY OVER SOUTHERN
WYOMING AS GUSTY NORTHWEST WINDS ALREADY DEVELOPING OVER CYS AND
SOUTHERN PORTIONS OF SOUTHERN WYOMING. SHOULD SEE WINDS SPREADING
OVER THE FRONT RANGE FOOTHILLS FROM 10Z-15Z. STILL SOME
OROGRAPHIC INDUCED SNOW SHOWERS ONGOING OVER THE HIGHER MOUNTAINS
BUT SHOULD SEE A DIMINISH OF THE SHOWERS AS THE DAY WEARS ON AS
HIGH PRESSURE RIDGE BUILDS IN.
WINDS WILL BE INCREASING ON THE PLAINS THIS AFTERNOON AS LOW
LEVELS OF AIRMASS MIX OUT TO NEAR 500MB UNDER SUBSIDENT AIRMASS.
COULD SEE SOME GUSTS UP AROUND 30KT. WINDS WILL DIMINISH ON THE
PLAINS THIS EVENING AS AIRMASS DECOUPLES. WILL SEE A CONTINUATION
OF THE WINDS IN THE MOUNTAINS AND FOOTHILLS TONIGHT AS CROSS
SECTIONS SHOW CROSS BARRIER FLOW AROUND 30KT. TEMPERATURES WILL BE
SLIGHTLY COOLER TODAY BEHIND THE TROF BUT COOLING MITIGATED BY THE
STRONGER DOWNSLOPE FLOW.
LONG TERM...STRONG UNDULATING UPPER LEVEL ZONAL ZONE WILL REMAIN
OVER THE WESTERN HALF OF THE COUNTRY THROUGH THE FORESEEABLE
FUTURE ACCORDING THE LATEST MODEL OUTPUT. WE BEGIN WITH A
SHORTWAVE RIDGE WHICH MODELS PROPAGATE ACROSS THE CENTRAL ROCKY
MOUNTAIN REGION THIS WEEKEND. AMBIENT AIRMASS WARMS AND BECOMES
STRONGLY CAPPED AT MID-LEVEL ON SATURDAY AS THE FRONT SIDE OF
THIS RIDGE MOVES ACROSS THE FORECAST AREA. SATURDAY MAY NOT BE
THE WARMEST OF THE TWO DAYS...BUT PROBABLY THE SUNNIEST. MEANWHILE
WIDESPREAD PRESSURE FALLS ACROSS THE NORTHERN GREAT PLAINS ON
SATURDAY WILL HELP TO ENHANCE THE DOWNSLOPE GRADIENT FLOW ALONG
AND EAST OF THE COLORADO FRONT RANGE DURING THE DAY. BY MID-
AFTERNOON COULD SEE SOUTHWEST WINDS GUSTING TO AROUND 25KTS ALONG
THE PALMER DIVIDE FROM WESTERN ELBERT TO LINCOLN COUNTIES. IN
ADDITION...MIN RELATIVE HUMIDITY VALUES COULD FALL TO AS LOW AS 15
PCT WITH LATE DAY TEMPERATURES IN THE MID TO UPPER 60S. SHOULD
LATER MODEL RUNS INDICATE STRONGER WINDS AND/OR LOWER RH VALUES
FOR A PERIOD LONGER THAN A FEW HOURS...IT MAY BE NECESSARY TO
ISSUE A FIRE WEATHER WATCH FOR THIS AREA. AS IT STANDS NOW NO
WATCH. BY SUNDAY...FLOW ALOFT TRANSITIONS FROM WEST-NORTHWESTERLY
TO SOUTHWESTERLY WITH THE PASSAGE OF THE 500MB RIDGE AXIS SATURDAY
NIGHT. THIS OPENS THE DOOR TO AN INFLUX OF HIGH LEVEL MOISTURE
LEADING TO A GRADUAL INCREASE IN HIGH LEVEL CLOUD COVER THROUGH
THE DAY. IN ADDITION...FLOW ALOFT IS FORECAST TO STRENGTHEN
THROUGH THE DAY WITH 45-60KT 700-500MB WINDS BY AFTERNOON. ON THE
PLAINS...PRESSURE FALLS AROUND A SFC LOW FORMING IN THE NEBRASKA
PANHANDLE WILL FURTHER ENHANCE TO SOUTH-SOUTHWEST WINDS ALREADY
ON THE PLAINS. BY AFTERNOON COULD SEE GUSTS IN THE 30-40KT RANGE
ALONG THE PALMER DIVIDE OUT TO THE KANSAS LINE. MAX TEMPERATURES
IN THE MID 60S TO LOWER 70S...RH VALUES POSSIBLY IN THE 8 TO 15
PCT RANGE AND THE GUSTY WINDS MENTIONED ABOVE WILL FURTHER
ENHANCE THE WILDLAND FIRE DANGER IN THIS AREA. NO FIREWEATHER
WATCH YET...HOWEVER ONE MAY BE ISSUED WITHIN THE NEXT 24 HOURS
FOR SUNDAY AFTERNOON AND EVENING. THAT SAID...WILL INTRODUCE
AREAS OF BLOWING DUST TO THE SUNDAY FORECAST FOR THE SOUTHEAST
CORNER OF THE FORECAST AREA. AS NOTED ABOVE...IT APPEARS SUNDAY
WILL BE THE WARMER OF THE TWO WEEKEND DAYS BUT MAY NOT SEE AS MUCH
SUNSHINE...ESPLY IN THE MTNS AND ACROSS THE NORTHEAST CORNER OF
THE STATE NEAR THE DEVELOPING SFC LOW. BY AFTERNOON COULD SEE
SCATTERED INSTABILITY SHOWERS FORMING IN THE HIGH COUNTRY AND BY
EVENING ACROSS THE FAR NORTHEAST CORNER OF THE STATE. CAN/T RULE
OUT A FEW T-STORMS AS WELL.
ON MONDAY...THE UPPER RIDGE SHIFTS EAST ALLOWING THE NEXT IN A
SERIES OF LOW AMPLITUDE SHORTWAVE TROUGHS TO PASS OVER THE STATE.
MODELS ALSO SHOW A COLD FRONT EXTENDING FROM THE SFC LOW NEAR THE
NORTHEAST TIP OF COLORADO PUSHING SOUTH ACROSS NORTHEASTERLY
COLORADO DURING THE EARLY MORNING HOURS. COOLING ALOFT WILL COMBINE
WITH THE INFLUX OF COOLER SFC AIR FROM WYOMING TO LOWER
TEMPERATURES TO NEAR OR SLIGHTLY BELOW AVERAGE ON MONDAY. THE
TROUGH QUICKLY MOVES OUT BY AFTERNOON ACCORDING TO MODELS AND WITH
DRYING AND SUBSIDENCE IN ITS WAKE SHOULD SEE LITTLE IF ANY PRECIP
ON MONDAY. INSTEAD NORTHWEST WINDS OF 30-40KTS ON THE PLAINS AND
FOOTHILLS DURING THE MORNING HOURS.
FOR THE REST OF THE WEEK...A WEAK SHORTWAVE RIDGE QUICKLY PASSES BY
MONDAY NIGHT...FOLLOWED BY ANOTHER SOMEWHAT STRONGER SHORTWAVE
TROUGH. MODELS SHOW THIS TROUGH DEEPENING OVER THE GREAT BASIN ON
TUESDAY AND MIGRATING OVER COLORADO BY WEDNESDAY. ANOTHER COLD
FRONT IS FORECAST TO SLIDE SOUTH ACROSS THE AREA AS THE TROUGH
PASSES. SHOULD SEE PRECIP CHANCES INCREASING FIRST IN THE HIGH
COUNTRY ON TUESDAY AND SPREADING TO NEARLY ALL ALL OF THE FORECAST
AREA BY WEDNESDAY. COULD SEE HIGHS ON WEDNESDAY SEVERAL DEGS BELOW
AVERAGE FOR THE DATE. COULD SEE THIS TROUGH HANG AROUND UNTIL
THURSDAY MORNING IF THE MODELS ARE CORRECT. AFTER THAT...DRIER
AND WARMER CONDITIONS RETURN WITH A STRONG UPPER RIDGE BUILDING
IN FROM THE GREAT BASIN.
AVIATION...SNOW HAS ENDED AT TERMINALS AS VFR CONDITIONS HAVE
RETURNED. MID LEVEL CLOUD DECK WILL DIMINISH BY DAYBREAK. EXPECT
INCREASING WEST TO NORTHWEST WINDS 15Z-19Z AND COULD SEE SOME
GUSTS UP AROUND 30KT THIS AFTERNOON WITH GOOD LOW LEVEL MIXING.
WINDS WILL DECREASE THIS EVENING WITH A RETURN TO DRAINAGE FLOW
FROM THE SOUTH AND SOUTHWEST.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...D-L
LONG TERM....BAKER
AVIATION...D-L
AREA FORECAST DISCUSSION
NWS TAUNTON MA
440 PM EDT FRI MAR 28 2014
.SYNOPSIS...
DRY WEATHER BRIEFLY RETURNS LATER TONIGHT INTO SATURDAY MORNING.
A COASTAL STORM DEVELOPS SOUTH OF NEW ENGLAND SATURDAY...BRINGING
A CHILLY...WINDSWEPT...SOAKING RAIN TO OUR REGION SATURDAY NIGHT
INTO SUNDAY. DRY WEATHER RETURNS AROUND TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
430 PM UPDATE...WINDS HAVE DIMINISHED A BIT ACROSS PORTIONS OF
SOUTHEAST MA. SOUTHWEST WINDS ARE FUNNELING UP BUZZARDS BAY AND
TAPPING INTO THE HIGHER WINDS ABOUT 3000 FEET AGL. EXPECTING
MIXING TO DIMINISH THIS EVENING...WHICH SHOULD DROP WIND GUSTS
BELOW ADVISORY CRITERION. WILL LEAVE THE WIND ADVISORY UP FOR THE
NEXT COUPLE OF HOURS.
LIGHT RAINFALL SPREADING EAST. 28/18Z HRRR IS THE MOST AGGRESSIVE
GENERATING MEASURABLE RAINFALL. RADAR TRENDS THOUGH INDICATE A
DRYING ACROSS MOST OF RI AND SOUTHEAST MA AS IT MOVES EAST.
THINKING PRIMARILY SPRINKLES FOR THOSE AREAS...BUT WILL NOT RULE
OUT THE POSSIBILITY OF A FEW LOCATIONS GETTING MEASURABLE
RAINFALL.
TEMPERATURES CONTINUE TO RISE ALONG THE IMMEDIATE EAST COAST...
THANKS TO THE PERSISTENT SOUTHWEST WINDS. NOW THAT THE CLOUDS HAVE
ARRIVED...WE SHOULD START THE SLOW FALL THROUGH THIS EVENING.
EXPECTING THE RAINFALL TO MOVE OFFSHORE BY MID EVENING...ALTHOUGH
A COLD FRONT WILL TAKE A LITTLE LONGER TO DO SO. ONCE THIS FRONT
MOVES OFFSHORE...EXPECTING AT LEAST PARTIAL CLEARING TO DEVELOP
FROM NORTH TO SOUTH.
IT WILL BE TOUGH FOR TEMPERATURES TO DROP MUCH TONIGHT...WITH A
DECENT SOUTHERLY WIND AND CLOUDS PERSISTING THROUGH THE EVENING.
THINKING IT WILL BE A CASE OF TEMPERATURES SLOWLY FALLING THIS
EVENING...THEN FALLING MUCH MORE QUICKLY AFTER MIDNIGHT WHERE THE
CLOUDS BREAK UP.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
DRY TO START ALONG WITH SOME PARTIAL SUNSHINE...ESPECIALLY ACROSS
NORTHERN MA INTO SOUTHWEST NH. A LOW PRESSURE DEVELOPS ALONG THIS
FRONT IN THE CENTRAL APPALACHIANS BY SATURDAY EVENING. HIGH
PRESSURE OVER QUEBEC...SHOULD KEEP THIS FRONT TO OUR SOUTH THROUGH
THE DAY. HOWEVER...THERE WILL BE PLENTY OF WARM CONVEYOR BELT
PROCESSES TO INCREASE CLOUDS AND RAINFALL CHANCES THROUGH THE
DAY.
TEMPERATURES SHOULD BE SIMILAR TO FRIDAY...MAINLY DUE TO THE
HIGHER STARTING POINT SATURDAY MORNING.
&&
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...
* POTENT STORM SYSTEM WITH A GAMUT OF HEADLINES POSSIBLE SATURDAY
NIGHT INTO SUNDAY.
* DRY WEATHER FOR THE MIDDLE OF THE WEEK
* MORE ACTIVE PATTERN FOR THE END OF THE WEEK
MODELS AND CONFIDENCE...
MODERATE CONFIDENCE IN THE OVERALL FORECAST ESPECIALLY BECAUSE OF
THE SIGNIFICANT SPREAD LATE NEXT WEEK. HOWEVER DO HAVE HIGH
CONFIDENCE THAT HEAVY PRECIP WILL OCCUR LATE SAT INTO SUN ACROSS A
GOOD PORTION OF THE REGION. MODERATE CONFIDENCE THAT SOME OF THAT
PRECIP WILL BE IN A WINTRY MIX LATE SUNDAY INTO MONDAY. LOWER
CONFIDENCE ON THE FORECAST FOR NEXT WEEK HOWEVER IT APPEARS THAT
THERE MAY BE A DRY DAY OR TWO THANKS TO HIGH PRESSURE.
12Z GUIDANCE IS IN GOOD AGREEMENT WITHIN THE MEDIUM
RANGE...HOWEVER IN THE LONG RANGE IT APPEARS TO HAVE SIGNIFICANT
DIFFERENCES. A STALLED LOW WILL MOVE OVER THE REGION LATE SATURDAY
AND STALL UNTIL MONDAY. UPPER LEVEL RIDGE WILL DEVELOP BY
TUESDAY/WEDNESDAY BEFORE ANOTHER STRONG UPPER LEVEL LOW MOVES INTO
THE REGION BY THE END OF THE WEEK. OVERALL TRENDED THE FORECAST
OUTSIDE OF THE SYSTEM TOWARD THE ENSEMBLES. DETAILS ON THE STALLED
LOW ARE BELOW.
DETAILS...
SATURDAY NIGHT INTO MONDAY...
* MODELS/OVERVIEW...A FRONT WILL STALL OVER THE REGION COMBINED
WITH THE APPROACHING UPPER LEVEL LOW...WILL BE THE FOCUS FOR THE
WEATHER OVER THE WEEKEND. DETAILS ON THE MODEL GUIDANCE...FIRST
THREW OUT THE NAM AS IT IS TO PROGRESSIVE AND THEREFORE BRINGING
A COLD BIAS INTO THE REGION THE LATE SUNDAY INTO MONDAY TIME
PERIOD. TRENDED TOWARDS THE EC/GFS AS THE MORE AMPLIFIED TREND
SEEM REASONABLE. THE OVERALL AXIS OF HEAVIER PRECIP ON BOTH OF
THE GFS AND EC HAS SHIFTED SLIGHTLY EASTWARD COMPARED TO 00Z
GUIDANCE. THIS GOES ALONG WITH THE THINKING OF THE ENSEMBLES.
OVERALL TRENDED THE FORECAST TO A 2:1 GFS TO EC COMBO WITH THE
QPF GEARED MORE TOWARDS THE RFC.
* DETAILS...STACKED COASTAL LOW WILL MOVE CLOSER TO THE REGION
SATURDAY NIGHT INTO SUNDAY RESULTING IN THE DEVELOPMENT OF A
STRONG SOUTHERLY LLJ BEHIND THE WARM FRONT. EXPECT HEAVY RAIN TO
START AFTER 06Z SAT NIGHT AS A BOUNDARY LAYER CONVERGENCE REGION
SETS UP ACROSS THE 95 CORRIDOR WITH EXCELLENT MOISTURE TRANSPORT
FEEDING INTO IT. THE LLJ WILL STRENGTHEN THROUGH THE MORNING
HOURS ON SUNDAY RESULTING IN SHOWALTER VALUES REACHING ABOVE 0C
AND K INDEX VALUES ABOVE 30C. THIS COULD DEVELOP SOME ISOLATED
THUNDER DURING THE DAY ON SUNDAY WHICH WILL BE CONFIDED TO THE
LOCATIONS SOUTH OF THE MASS PIKE INCLUDING THE WATERS. THIS
COINCIDES WITH THE NOSE OF THE LLJ. INTERESTING NOTE IS THAT THE
BOUNDARY LAYER MOISTURE CONFERENCE JUST SITS OVER THE 95
CORRIDOR THROUGH 00Z MONDAY. THIS GIVES FORECASTER CONFIDENCE
THAT THE AXIS OF HEAVIER PRECIP WILL SIT JUST ALONG OR NW OF
THIS CONVERGENCE AREA. A DRY SLOW WILL TRY TO MAKE ITS WAY OVER
THE CAPE AND THE ISLANDS BY LATE SUNDAY AS THE SYSTEM DEEPENS
AND BEGINS TO DEVELOP A TROWAL FEATURE ON THE BACKSIDE. AS THE
LOW PRESSURE SYSTEM MOVES EASTWARD...THIS TROWAL FEATURE WILL
BECOME MORE PRONOUNCE AND WITH STRONG NORTHERLY WINDS ON THE
BACKSIDE OF THE SYSTEM EXPECT SOME WINTRY PRECIP. RIGHT NOW IT
APPEARS THAT THE MAIN P-TYPE WILL BE IN THE FORM OF A COLD RAIN
WITH SOME SLEET OF FREEZING RAIN MIXED IN AS TEMPERATURES AT
THE SURFACE WILL DROP FASTER THAN ALOFT. THIS MIXING WILL LAST
INTO MONDAY BEFORE THE SYSTEM PULLS OUT OF THE REGION ENTIRELY
BY MONDAY AFTERNOON.
* IMPACTS...HAVE INCREASING CONFIDENCE THAT HEAVY PRECIP WILL
OCCUR AND A MODERATE CONFIDENCE THAT OVER 2 INCHES WILL FALL
ACROSS SOUTHERN NEW ENGLAND BETWEEN SAT EVENING INTO SUNDAY
NIGHT. THEREFORE WE HAVE ISSUED A FLOOD WATCH FOR AREAS THAT
MAY SEE NOT ONLY A GOOD AMOUNT OF QPF BUT ALSO THE POTENTIAL FOR
RIVER RISE. THE 12Z GEFS HAVE A 60-70 PERCENT PROBABILITY OF
EXCEEDING 2 INCHES AND WITHIN A 24 HOUR PERIOD BOTH THE GFS AND
EC SHOW THE POSSIBILITY OF OVER 2 INCHES. TRENDED THE FORECAST
TOWARDS A COMBINATION OF THE GFS/EC AND RFC FOR QPF. AT MOST A
FEW OF THE MAIN STEM RIVERS MAY RISE INTO ACTION AND MAY TOUCH
FLOOD STAGE DEPENDING ON WHERE THE HEAVIEST QPF FALLS AS WELL AS
SNOW MELT AND ICE JAM POTENTIAL. IF WE ANTICIPATE 3 OR MORE THEN
WE MAY HAVE TO START LOOKING AT RIVER FLOODING POTENTIAL...MORE
DETAILS BELOW. AS MENTIONED ABOVE APPEARS THAT ELEVATED THUNDER
WILL OCCUR ON SUNDAY...DO NOT ANTICIPATE ANY STRONG OR SEVERE
WEATHER AT THIS TIME. BECAUSE OF THE STRONG LLJ WE COLD SEE WIND
ADV HEADLINES ACROSS THE CAPE AND THE ISLANDS BUT LEFT THE
POTENTIAL OUT FOR NOW AS CONFIDENCE IS LOWER. ON THE BACKSIDE OF
THIS SYSTEM...TEMPERATURES COULD DROP BELOW 32 AND WITH TEMPS
ALOFT BEING 2-3C ABOVE 0 THEN THERE IS THE POTENTIAL FOR ICE ESP
ACROSS THE NW PORTION OF THE FORECAST REGION. HOWEVER IF DYNAMIC
COOLING OCCURS AND THE SYSTEM CAN DRAW THAT COLD AIR ALOFT DOWN
TO THE LOW LEVELS THEN THERE MAY BE SLEET/SNOW ON THE BACKSIDE.
THIS ICE/SLEET POTENTIAL LINES UP WITH WPC GRAPHICS. THERE IS
ALSO THE POTENTIAL FOR MINOR COASTAL FLOODING ALONG BOTH THE
SOUTH COAST AND EAST COAST SHORELINES FOR MULTIPLE HIGH TIDE
CYCLES...MORE DETAILS BELOW.
TUESDAY AND WEDNESDAY....
WEAK RIDGING ALOFT WILL SET-UP ACROSS THE AREA ON TUESDAY AND
WEDNESDAY YIELDING TO HIGH PRESSURE AND HOPEFULLY DRY WEATHER.
TEMPERATURES WILL BE CLOSER TO SEASONABLE THANKS TO A THERMAL RIDGE.
THURSDAY AND BEYOND...
SEVERAL RIPPLES MOVING THROUGH THE LONG WAVE RIDGE WILL YIELD TO
CLOUDS AND SHOWERY WEATHER. TEMPERATURES WILL BE CLOSE TO
SEASONABLE.
&&
.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
OVERALL FORECAST CONFIDENCE IS MODERATE THROUGH SATURDAY. HAVE
HIGH CONFIDENCE IN TRENDS...BUT ONLY MODERATE CONFIDENCE IN
TIMING.
THROUGH 00Z...MAINLY VFR OUTSIDE OF SHOWERS...WITH MVFR IN
ANY SHOWERS. LOCAL IFR DEVELOPING ACROSS THE HIGHER TERRAIN OF
CENTRAL MA AND SOUTHWEST NH.
TONIGHT...FRONT SLIPS SOUTH OF NEW ENGLAND. MVFR/IFR IMPROVES TO
VFR...TAKING LONGEST ALONG THE SOUTH COAST. ANY LINGERING RAIN
SHOWERS ON THE SOUTH COAST MOVE OFFSHORE LATE THIS EVENING.
SATURDAY...VFR AND DRY TO START...THEN LOWERING TO MVFR AS RAIN
MOVES NORTH LATER IN THE AFTERNOON.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF. SW WINDS MAY BRIEFLY GUST
UP TO 35 KT LATE THIS AFTERNOON.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK...SATURDAY NIGHT THROUGH WEDNESDAY...
SATURDAY NIGHT THROUGH MONDAY...MODERATE CONFIDENCE. AREAS OF MVFR
CIGS/VSBYS IN HEAVY RAIN/FOG. A WINTRY MIX IS POSSIBLE LATE SUNDAY
NIGHT INTO MONDAY AS PRECIP COMES TO AN END.
TUESDAY INTO WEDNESDAY...MODERATE TO HIGH CONFIDENCE. IMPROVING
CONDITIONS AS RAIN MOVES OUT OF THE REGION...VFR.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
MODERATE TO HIGH FORECAST CONFIDENCE THRU SAT NIGHT.
TONIGHT...
A COLD FRONT MOVES OFFSHORE WITH WINDS DIMINISHING AND SHIFTING
FROM SW TO WNW BY SATURDAY MORNING. WILL NEED TO REPLACE GALE
WARNINGS WITH SMALL CRAFT ADVISORIES AS WINDS DIMINISH THIS
EVENING.
SATURDAY...
WARM FRONT LIFTS NORTH WITH INCREASING SOUTH WINDS ACROSS THE
SOUTHERN OUTER COASTAL WATERS. RAIN ALSO OVERSPREADS SOUTHERN
WATERS.
OUTLOOK...SATURDAY NIGHT THROUGH WEDNESDAY...
SATURDAY NIGHT THROUGH MONDAY...LOW TO MODERATE CONFIDENCE. GALE
WARNINGS WILL LIKELY BE NEEDED FOR SOME OF THE COASTAL WATERS AS LOW
PRESSURE MOVES OVER THE WATERS. SEAS INCREASE TO 10 TO 15 FEET ON
THE OUTER WATERS. VISIBILITIES WILL LIKELY BE LIMITED AT TIMES IN
HEAVY RAIN AND FOG.
TUESDAY INTO WEDNESDAY...WINDS AND SEAS DIMINISH AS WEAK HIGH
PRESSURE BEGINS TO BUILD OVER THE WATERS.
&&
.HYDROLOGY...
MARCH PRECIPITATION HAS BEEN MOSTLY SPARSE ACROSS SOUTHERN NEW
ENGLAND...BUT WE MAY MAKE UP FOR THIS IN ABUNDANCE DURING THIS
WEEKEND. RIVERS AND STREAMS ARE RUNNING BELOW NORMAL FOR THIS TIME
OF YEAR...WHICH PROVIDES US A BUFFER. HOWEVER...THE POTENTIAL FOR 2
TO 4 INCHES OF RAINFALL WITH VEGETATION STILL DORMANT
...PLUS SNOWMELT IN THE FAR INTERIOR...IS SUFFICIENT TO BRING THE
CONCERN OF MINOR FLOODING ON AREA RIVERS AND STREAMS. THE MAIN AREA
OF CONCERN AT THIS TIME IS INTERIOR SOUTHERN NEW ENGLAND...AND THIS
IS WHERE FLOOD WATCHES ARE GOING INTO EFFECT. POOR DRAINAGE AREAS
...SMALL STREAMS...AND SOME LARGER TRIBUTARY RIVERS WILL BE AT RISK.
IN ADDITION...THE MORE VULNERABLE FORECAST LOCATIONS ON THE LOWER
MAINSTEM CONNECTICUT RIVER WILL NEED TO BE MONITORED OVER THE
COURSE OF THIS EVENT.
FOR RIVER FORECAST POINTS THAT ARE BEING MONITORED...GO TO
HTTP://WATER.WEATHER.GOV/AHPS2/FORECASTS.PHP?WFO=BOX . LOCATIONS OF
MAIN CONCERN ARE THOSE FORECAST TO GO TO ACTION STAGE OR HIGHER.
NOTE THAT THE FORECASTS GO OUT 72 HOURS...AND IN SOME INSTANCES THE
GAUGES ARE FORECAST TO BE CLIMBING THROUGH THE END OF THE
FORECAST PERIOD. AS MENTIONED...AT THIS TIME MINOR FLOODING IS
EXPECTED TO BE THE THREAT ON THE LARGER RIVERS.
WHILE REPORTS FROM OFFICIALS IN THE INTERIOR INDICATE RIVER ICE HAS
DECREASED IN COVERAGE AND THICKNESS OVER THE PAST TWO WEEKS...THERE
ARE STILL INDICATIONS THAT SOME RIVERS AND STREAMS IN SOUTHWEST NEW
HAMPSHIRE AND FAR NORTHWEST MASSACHUSETTS HAVE SUFFICIENT ICE TO
WARRANT A LOW RISK OF ICE JAMS AND ICE JAM RELATED FLOODING. WORDING
IN THE FLOOD WATCH IS BEING MENTIONED ACCORDINGLY.
&&
.TIDES/COASTAL FLOODING...
THE WEEKEND INTO EARLY NEXT WEEK SYSTEM POSES SOME RISK OF
COASTAL FLOODING AND BEACH EROSION SINCE THE ASTRONOMICAL HIGH
TIDES ARE RELATIVELY HIGH. THE SITUATION IS A BIT COMPLICATED WITH
BOTH SOUTH AND EAST COASTS AS WELL AS MULTIPLE HIGH TIDE CYCLES AT
RISK. AT THIS TIME THE IMPACT LOOKS TO BE MOSTLY MINOR BUT JUST A
FAIRLY MODEST STRENGTHENING OF THE COASTAL LOW AND ASSOCIATED LOW
LEVEL JET COULD RESULT IN A MODERATE IMPACT AT A FEW LOCATIONS.
SINCE THE EVENT IS STILL 2 TO 3 DAYS OUT...THE ONLY HEADLINE
ISSUED NOW IS A COASTAL FLOOD ADVISORY FOR PORTIONS OF THE RI AND
MA SOUTH COAST FOR THE SUN MORNING HIGH TIDE. ADDITIONAL HEADLINES
MAY BE NEEDED DURING THE COURSE OF THE WEEKEND.
SOUTH COAST...HAVE AT LEAST MODERATE CONFIDENCE OF MINOR COASTAL
FLOODING DURING THE SUNDAY MORNING HIGH TIDE IN PORTIONS OF
NARRAGANSETT BAY AND OTHER PORTIONS OF THE RI/MA COAST INCLUDING
WESTPORT. A VIGOROUS LOW LEVEL JET OF 50 TO 60 KT ON BOTH THE GFS
AND ECMWF IS EXPECTED TO INDUCE A 1 TO 1.8 FOOT SURGE...HIGHEST
UPPER PART OF NARRAGANSETT BAY...FOR THE SUN MORNING HIGH TIDE.
WAVES APPROACHING 10 FT JUST OFFSHORE MAY BE SUFFICIENT FOR SOME
SPLASHOVER AT THE TIME OF THE HIGH TIDE ALONG SOME SOUTH COAST
EXPOSED BEACHES SUCH AS THE NEWPORT AND WESTPORT SOUTH COAST
BEACHES AS WELL AS THE WEST ISLAND CAUSEWAY IN FAIRHAVEN. LESS
CONFIDENT ON ANY IMPACTS FOR THE SUN EVENING HIGH TIDE. ANTICIPATE
THE S OR SE FLOW TO HAVE DIMINISHED OR ENDED BUT WATER MAY BE
SLOW TO EVACUATE FROM A FEW LOCATIONS INCLUDING NARRAGANSETT BAY
WITH PRES FALLS BEING A POSSIBLE SECONDARY FACTOR.
EAST COAST OF MA...A N TO NNE FLOW BECOMES ESTABLISHED LATE SUN
THROUGH MON AND THEN BECOMING MORE NNW BY MON NIGHT. A LOW LEVEL
JET OF 40 TO 50 KT IMPACTS THE COASTLINE N OF BOS FOR THE SUN
NIGHT HIGH TIDE AND MOST OF THE MA E COAST FOR THE MON MIDDAY HIGH
TIDE. THERE IS SOME SUGGESTION...ESPECIALLY FROM THE ECMWF
MODEL...THAT THE LOW LEVEL JET MAY PERSIST TO IMPACT THE HIGH TIDE
AROUND 1 AM TUE FOR NANTUCKET HARBOR AND THE N SIDE OF CAPE COD.
ALTHOUGH AT THIS TIME THE IMPACTS LOOK TO BE MOSTLY
MINOR...MULTIPLE HIGH TIDE CYCLES ARE LIKELY TO BE INVOLVED AND
JUST A MODESTLY STRONGER SYSTEM AND ASSOCIATED NNE WINDS COULD
RESULT IN POCKETS OF MODERATE IMPACTS. GIVEN THAT MULTIPLE TIDE
CYCLES WILL LIKELY BE AFFECTED...AT LEAST SOME BEACH EROSION IS
LIKELY FROM SALISBURY TO CAPE ANN INCLUDING PLUM ISLAND...THE
PLYMOUTH COUNTY COAST...N AND OCEAN SIDES OF CAPE COD AND THE E
SIDE OF NANTUCKET BEFORE THIS EVENT IS OVER.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH FROM SATURDAY EVENING THROUGH MONDAY MORNING FOR
CTZ002>004.
MA...WIND ADVISORY UNTIL 6 PM EDT THIS EVENING FOR MAZ018>023.
COASTAL FLOOD ADVISORY FROM 6 AM TO 10 AM EDT SUNDAY FOR
MAZ020.
FLOOD WATCH FROM SATURDAY EVENING THROUGH MONDAY MORNING FOR
MAZ002>006-008>012-026.
NH...FLOOD WATCH FROM SATURDAY EVENING THROUGH MONDAY AFTERNOON FOR
NHZ011-012-015.
RI...COASTAL FLOOD ADVISORY FROM 6 AM TO 10 AM EDT SUNDAY FOR
RIZ002-004-005-007.
FLOOD WATCH FROM SATURDAY EVENING THROUGH MONDAY MORNING FOR
RIZ001.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EDT SATURDAY FOR ANZ231>234.
GALE WARNING UNTIL 10 PM EDT THIS EVENING FOR ANZ230-251.
SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR ANZ236.
SMALL CRAFT ADVISORY UNTIL NOON EDT SATURDAY FOR ANZ235-237-
254.
SMALL CRAFT ADVISORY UNTIL 6 AM EDT SATURDAY FOR ANZ250.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR ANZ255-256.
&&
$$
SYNOPSIS...BELK/DUNTEN
NEAR TERM...BELK
SHORT TERM...BELK
LONG TERM...DUNTEN
AVIATION...BELK/DUNTEN
MARINE...BELK/DUNTEN
HYDROLOGY...NMB
TIDES/COASTAL FLOODING...THOMPSON
AREA FORECAST DISCUSSION
NWS ALBANY NY
422 PM EDT FRI MAR 28 2014
.SYNOPSIS...
A FRONTAL BOUNDARY WILL MOVE ACROSS THE REGION TONIGHT WITH
IMPROVING CONDITIONS DEVELOPING FROM WEST TO EAST. ANOTHER STORM
SYSTEM APPROACHES AND WILL BRING MODERATE TO HEAVY AMOUNTS OF
PRECIPITATION FOR MOST OF THIS WEEKEND. THE POTENTIAL FOR
FLOODING AND ICE JAMS INCREASES ALONG WITH WINTER WEATHER
CONCERNS ACROSS THE ADIRONDACKS. OUR WEATHER IS EXPECTED TO
IMPROVE INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
TEMPERATURES ACROSS CENTRAL AND WESTERN NEW YORK HAVE RISEN WELL
INTO THE 50S AS THIS REGION HAS BEEN PRECIPITATION FREE THE PAST
SEVERAL HOURS /EVEN SOME BREAKS IN THE CLOUD COVER SEEN IN THE 1KM
VISIBLE IMAGERY/. WE STILL HAVE A FEW MORE HOURS OF DAYLIGHT AS WE
STILL COULD ACHIEVE OUR MILDER TEMPERATURES AND WE WILL RETAIN THE
HOURLY GRIDS WITH SLIGHT MODIFICATIONS PER OBSERVATIONS.
COLD FRONT WAS JUST APPROACHING EXTREME WESTERN NY AS SHOWERS WERE
JUST DEVELOPING AT THE TIME OF WRITING THIS DISCUSSION. PER THE
LATEST HRRR REFLECTIVITY FORECASTS...SEEMS THESE SHOWERS WILL MOVE
ACROSS THE REGION THROUGH EARLY THIS EVENING. THE THERMAL CONTRAST
WITH FROPA IS NOT THAT NOTICEABLE AS LATEST MOS GUIDANCE CAPTURES
THIS IDEA AS WE WILL LEAN TOWARD A SLIGHTLY WARMER OVERNIGHT LOWS.
RIDGE OF HIGH PRESSURE IS EXPECTED TO BUILD INTO THE REGION
OVERNIGHT WITH GRADUALLY IMPROVING SKY CONDITIONS FROM WEST TO
EAST.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
...FLOOD WATCH IN EFFECT OUTSIDE OF THE ADIRONDACKS...
...WINTER STORM WATCH IN EFFECT FOR THE ADIRONDACKS...
H2O VAPOR LOOP REVEALS THE KEY PLAYERS WITH A COUPLE OF NOTABLE
UPPER LEVEL WAVES ACROSS THE PLAINS. MODEL DIAGNOSIS HAS COME INTO
A RATHER GOOD AGREEMENT OF PHASING EVOLVING ACROSS THE
OHIO/TENNESSEE VALLEY TRANSITIONING INTO AN CLOSED UPPER LOW OVER
THE MID ATLANTIC REGION. THERMAL PROFILES CONTINUE TO WARM IN THE
GLOBAL MODELS AS THE NAM REMAINS TOO COLD. COMBINATION OF MODERATE
TO HEAVY QPF...THERMAL PROFILES LINING UP ACROSS THE
ADIRONDACKS...WARMING THERMAL PROFILES FOR ICE BEGINNING TO MOVE
ALONG THE RIVERS/STREAMS COULD RESULT IN ICE JAMS. NOW ONTO THE DETAILS...
SATURDAY...
MOST OF THE DAY SHOULD BE RATHER TRANQUIL AS WE BEGIN THE DAY
RATHER DRY WITH PARTIAL SUNSHINE IN THE MORNING. CLOUDS WILL
EVENTUALLY INCREASE FROM SOUTH TO NORTH AS TEMPERATURES ACROSS
MOST OF THE REGION MODERATING INTO THE 40S WITH COOLER 30S ACROSS
THE ADIRONDACK REGION. THESE TEMPS WILL BE KEY TO THE PRECIP TYPE
EXPECTED SATURDAY NIGHT.
SATURDAY NIGHT...
CROSS SECTIONS AND BUFR PROFILES WITH RESPECT TO TEMPERATURES
REVEAL A RATHER SHARP CONTRAST ACROSS THE ADIRONDACK REGION. THE
LOW LEVEL AGEOSTROPHIC FLOW INCREASES FROM THE NORTH WHICH COULD
KEEP THE NEAR SURFACE TEMPERATURES NEAR OR JUST BELOW FREEZING.
THIS COULD RESULT IN A PERIOD OF SLEET OR FREEZING RAIN
ACCUMULATION ACROSS THIS REGION AND PER COLLABORATION FROM
SURROUNDING WFOS AND WPC WWD...WE WILL HOIST A WINTER STORM WATCH
FOR THIS REGION.
OUTSIDE OF THIS REGION...A MODERATE TO HEAVY RAINFALL EVENT SEEMS
TO BE UNFOLDING AS PWAT ANOMALIES OF 1-3 STANDARD DEVIATIONS ABOVE
NORMAL...ASSOCIATED LOW LEVEL SOUTHERLY WIND ANOMALIES AND
IMPRESSIVE 2D FGEN OVERHEAD TO BRING ABOUT A PERIOD OF VERY WET
WEATHER. PLEASE REFER TO THE HYDROLOGY DISCUSSION BELOW FOR
FURTHER DETAILS.
SUNDAY...
MID LEVEL DRY SLOT APPROACHES AND SHOULD DIMINISH THE PRECIP
INTENSITY ACROSS THE AREA. DEFORMATION AXIS PER THE GLOBAL MODELS
APPEARS TO LINE UP JUST WEST OF OUR SERVICE AREA /NEAR I81/ SO THE
PRECIP THROUGH THE DAY IS EXPECTED TO REMAIN LIGHT. WE WILL LOWER
POPS ACCORDINGLY AS COLDER AIR ATTEMPTS TO SEEP INTO THE DACKS
WHERE ADDITIONAL LIGHT ACCUMULATIONS ARE POSSIBLE.
SUNDAY NIGHT...
THE AFOREMENTIONED DEFORMATION AXIS IS EXPECTED TO MIGRATE ACROSS
THE REGION...MEANWHILE...LOW LEVEL COLD ADVECTION IS FORECAST TO
INCREASE. THIS WOULD SUGGEST ANOTHER PERIOD OF WET WEATHER
TRANSITIONING TOWARD WINTRY TYPE PRECIPITATION ISSUES DEVELOPING
ACROSS THE ENTIRE REGION. THE LATEST ECMWF IS SUGGESTING QUITE A
STRONG SIGNAL THAT LATER FORECAST SHIFTS CAN FINE TUNE.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
THE LONG TERM STARTS WITH THE CUTOFF LOW STILL BRINGING RESIDUAL
CLOUDS AND SHOWERS...MAINLY FROM THE HUDSON VALLEY EASTWARD ON
MONDAY. THIS LOW IS FORECAST TO SLOWLY PULL AWAY FURTHER EAST THAT
DAY...WITH CONDITIONS SLOWLY IMPROVING. HOWEVER...SINCE ANY SUNSHINE
WOULD GENERALLY BE LIMITED TO LATER IN THE DAY...WE HAVE TRIMMED
HIGH TEMPERATURES BACK FOR THAT DAY...GENERALLY LOOKING AT 50-55
ALBANY SOUTHWARD...40S FURTHER NORTH WEST AND EVEN EAST OF ALBANY
(WHERE CLOUDS WILL LINGER THE LONGEST).
RIDGE OF HIGH PRESSURE FINALLY BUILDS IN MONDAY NIGHT INTO TUESDAY.
THE QUESTION IS WHETHER OR NOT CLOUDS COULD REFORM UNDERNEATH AN
INVERSION MONDAY NIGHT. FOR NOW...WE PLAYED IT CAUTIOUSLY OPTIMISTIC
AND WENT WITH PARTLY CLOUDY MONDAY NIGHT. IF WE WERE TO
CLEAR...THERE COULD BE SOME FOG ISSUES TO DEAL WITH ALONG WITH LOWER
TEMPERATURES THAN WE ARE CURRENTLY FORECASTING. FOR NOW...WE LEFT
FOG OUT OF THE FORECAST SINCE THIS IS STILL SEVERAL DAYS OUT.
WITH PARTIAL CLEARING....LOOK FOR LOWS TO SLIP BACK INTO THE LOWER
TO MID 30S FROM THE CAPITAL REGION SOUTHWARD...20S FURTHER NORTH AND
ACROSS MUCH OF ELEVATED TERRAIN.
TUESDAY...FINALLY...LOOKS LIKE THE DAY MOST OF US HAVE BEEN WAITING
FOR. IT WILL MARK THE BEGINNING OF APRIL AND WE WILL LEAVE THE CHILL
OF MARCH BEHIND. EVEN IF WE DO START THE DAY CLOUDY...THEY SHOULD
BREAK UP FAIRLY QUICKLY. H850 TEMPERATURES LOOK TO WARM BACK UP TO
ABOUT +5C. WITH A STRONG APRIL SUNSHINE AND FAIRLY GOOD
MIXING...TEMPERATURES LOOK TO CLIMB TO THE UPPER 40S TO LOWER 50S
ACROSS THE ADIRONDACKS AND SOUTHERN GREENS...MID TO UPPER 50S ACROSS
THE REMAINDER OF THE REGION...WITH PERHAPS A FEW SPOTS IN THE MID
HUDSON VALLEY...TOUCHING 60 DEGREES. THE WIND SHOULD BE LIGHT SO IT
WILL FEEL PLEASANT OUTDOORS TO MOST FOLKS AND FINALLY FEEL LIKE
SPRING.
A WEAK SYSTEM FROM SOUTHERN CANADA LOOK TO BRING A FEW RAIN OR SNOW
SHOWERS...MAINLY NORTH OF THE CAPITAL REGION TUESDAY NIGHT INTO
WEDNESDAY. THIS SYSTEM LOOKS MOISTURE STARVED AT THIS POINT...SO ANY
PRECIPITATION LOOKS LIGHT. THIS STORM WILL DRAG A COLD FRONT THROUGH
THE MOST OF THE REGION BY WEDNESDAY...COOLING TEMPERATURES DOWN A
LITTLE. A WEST TO NORTHWEST BREEZE WILL HOLD TEMPERATURES IN THE
LOWER 50S LOCALLY IN THE CAPITAL REGION ON WEDNESDAY...MAINLY 40S
NORTH. TO THE LEE OF THE CATSKILLS...INCLUDING THE MID HUDSON VALLEY
AND LITCHFIELD COUNTY...THANKS TO A DOWNSLOPING WIND AND ABUNDANT
SUNSHINE...TEMPERATURES WILL ONCE AGAIN BOUNCE INTO THE MID OR UPPER
50S. THE REST OF THE REGION WILL RANGE FROM MOSTLY CLOUDY
(MOUNTAINS) TO PARTLY SUNNY(MOHAWK VALLEY AND GREATER CAPITAL
REGION).
HIGH PRESSURE WILL ATTEMPT TO WEDGE INTO THE REGION FROM SOUTH
CENTRAL CANADA LATER WEDNESDAY INTO THURSDAY. AT THE SAME TIME
HOWEVER...ANOTHER CUTOFF LOW PRESSURE IS FORECAST TO GATHER STRENGTH
IN THE NATION/S MIDSECTION.
THE QUESTION IS WHETHER OR NOT HIGH PRESSURE WILL TAKE CONTROL AND
KEEP THE CUTOFF TO OUR SOUTHWEST FOR THE REMAINDER OF THE WEEK.
OR...WILL THE LOW PRESSURE SLOWLY WORK INTO OUR REGION? THE FORMER
SOLUTION IS OFFERED BY THE 12Z EUROPEAN MODEL WHILE THE LATTER
WETTER SOLUTION IS FORECASTED BY THE 12Z GFS.
FOR NOW...FOLLOWED MAINLY THE WEATHER PREDICTION CENTER`S TAKE ON
THINGS (WPC)...WHICH LEANED MORE WITH THE WETTER GFS. WE HAVE SLIGHT
CHANCES OF POPS IN FOR THURSDAY...INCREASING THEM TO CHANCE THURSDAY
NIGHT THROUGH FRIDAY.
HIGH TEMPERATURES ON THURSDAY AND FRIDAY WILL BE HIGHLY DEPENDENT ON
CLOUD COVER. SINCE WE ARE GOING WITH INCREASING CLOUDS ON
THURSDAY...AND CLOUDY WITH BETTER CHANCES FOR SHOWERS FRIDAY...WENT
WITH SEASONABLE TEMPERATURES THURSDAY (MID 40S NORTH TO MID 50S
SOUTH) AND COOLER TEMPERATURES FRIDAY (LOWER 40S NORTH TO LOWER 50S
SOUTH).
IT MIGHT BE COLD ENOUGH THURSDAY NIGHT FOR SOME MOUNTAIN SNOWS...BUT
MOST VALLEY AREAS SHOULD REMAIN ALL RAIN.
&&
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
AS A COLD FRONT APPROACHES THE REGION...AN AREA OF RAIN THIS AFTERNOON
WILL TAPER OFF TO SHOWERS BY THIS EVENING. WITHIN THIS
RAINFALL...FLYING CONDITIONS WILL GENERALLY BE MVFR...BUT BRIEF
PERIODS OF IFR CIGS/VSBYS CANNOT BE RULED OUT FOR KGFL/KPSF/KALB
THROUGH THE EARLY EVENING HOURS. HAVE ACCOUNTED FOR THIS WITH A
TEMPO GROUP. SOUTHERLY SFC WINDS WILL BE AROUND 10 KTS...WITH A
FEW HIGHER GUSTS FOR KALB...AS AIR IS FUNNELED UP THE HUDSON
VALLEY.
THE THREAT FOR RAINFALL WILL END THIS EVENING WITH THE PASSAGE OF
THE COLD FRONT. FLYING CONDITIONS WILL STILL BE MVFR FOR A FEW
HOURS DUE TO LINGERING LOW LEVEL MOISTURE KEEPING CIGS AROUND 1-3
KFT. BY LATER TONIGHT...A DRIER W-NW FLOW AT 5-10 KTS WILL ALLOW
FOR VFR CONDITIONS TO RETURN WITH JUST SOME REMAINING SCT CLOUDS
AROUND.
LIGHT N-NE WINDS WILL BE IN PLACE FOR SATURDAY MORNING WITH NO
PRECIPITATION. HOWEVER...MID AND HIGH LEVEL CLOUDS WILL INCREASE
THROUGH THE MORNING HOURS FROM SOUTH TO NORTH AS A STORM ORGANIZES
OVER THE MID ATLANTIC REGION. SOME RAIN WILL SPREAD BACK INTO THE
REGION FROM SOUTH TO NORTH DURING THE AFTN HOURS...WITH MVFR
CONDITIONS /MAINLY DUE TO VSBYS/ EXPECTED.
OUTLOOK...
SATURDAY AFTN: HIGH OPERATIONAL IMPACT. LIKELY RA.
SATURDAY NIGHT: HIGH OPERATIONAL IMPACT. DEFINITE RA...SLEET.
SUNDAY: HIGH OPERATIONAL IMPACT. BREEZY. DEFINITE RA.
SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. BREEZY. CHANCE OF
SHRA...SHSN.
MONDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
MONDAY NIGHT TO WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
NO FIRE WEATHER RELATED ISSUES ARE EXPECTED THROUGH AT LEAST THE
NEXT SEVERAL DAYS. THE WET WEATHER OF TODAY AND THEN A STRONGER
COASTAL SYSTEM EXPECTED TO BRING MODERATE TO HEAVY AMOUNTS OF
PRECIPITATION TO THE REGION OVER THE WEEKEND. SOME OF THE
PRECIPITATION MAY FALL AS SNOW OR A WINTRY MIX...ESPECIALLY ACROSS
THE HIGHER TERRAIN.
&&
.HYDROLOGY...
THERE WILL BE AN INCREASING POTENTIAL FOR HYDROLOGIC
ISSUES...INCLUDING RIVER ICE BREAK UP AND POSSIBLE FLOODING...OVER
THE WEEKEND. FLOOD WATCH IS NOW IN EFFECT OUTSIDE OF THE
ADIRONDACK REGION.
RAINFALL AMOUNTS CLOSE TO ONE HALF OF AN INCH HAVE BEEN OBSERVED
WITH SOME SLIGHT INCREASE NOTICED ON RIVER GAGES.
HOWEVER...TEMPERATURES HAVE BEEN SLOW TO RISE WHICH HAS ASSISTED
WITH THE RAINFALL LIKELY BEING ABSORBED INTO THE SNOWPACK AND
LITTLE ICE MOVEMENT AT THIS TIME.
HOWEVER...A MORE SIGNIFICANT STORM SYSTEM WILL MOVE FROM THE MID
ATLANTIC COAST TOWARDS NEW ENGLAND FOR LATE SATURDAY INTO SUNDAY.
THIS SYSTEM HAS THE POTENTIAL TO BRING MODERATE TO HEAVY AMOUNTS
OF PRECIPITATION TO THE REGION...ESPECIALLY FOR AREAS FROM THE
CAPITAL REGION SOUTH AND EAST...WITH MODEL CONSENSUS SHOWING ONE
TO THREE INCHES OF RAINFALL ACROSS SOUTHEASTERN PARTS OF THE
REGION. WHILE MUCH OF THIS WILL BE IN THE FORM OF RAINFALL...THERE
IS THE POTENTIAL FOR THE PRECIP TO CHANGE TO A WINTRY MIX OR
SNOWFALL BEFORE ENDING...MAINLY FOR NORTHERN AND HIGH TERRAIN
AREAS.
CURRENT NERFC RIVER FORECASTS SHOW RISING LEVELS TO NEAR OR ABOVE
FLOOD STAGE. THERE IS THE POTENTIAL FOR SIGNIFICANT
RISES...ESPECIALLY ACROSS THE HOUSATONIC BASIN...AND SUBSEQUENT
RIVER ELEVATION FORECASTS MAY NEED TO BE INCREASED IF THE LATEST
TRENDS IN MODEL GUIDANCE ARE CORRECT. ALTHOUGH QPF AMOUNTS ARE
ARE NOW FORECAST TO RANGE BETWEEN 1 AND 3 INCHES...THE CHALLENGE
IS ICE BREAKING UP ON LARGER MAIN STEM RIVERS AS WELL...WHICH COULD
POTENTIALLY CAUSE ICE JAMS IN SOME LOCATIONS. WITH THE BULK OF THE
RAINFALL EXPECTED TO OCCUR SATURDAY NIGHT IN A RELATIVELY SHORT
PERIOD OF TIME...SOME MINOR URBAN...LOW LYING...AND SMALL STREAM
FLOODING COULD POTENTIALLY OCCUR AS WELL. THE MOST LIKELY AREAS TO
SEE ISSUES WOULD BE FROM THE MOHAWK BASIN SOUTH AND EAST.
DRIER WEATHER LOOKS TO RETURN FOR MONDAY THROUGH WEDNESDAY OF NEXT
WEEK...ALLOWING RIVERS AND STREAMS TO SLOWLY RECEDE.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH FROM SATURDAY EVENING THROUGH MONDAY MORNING FOR
CTZ001-013.
NY...FLOOD WATCH FROM SATURDAY EVENING THROUGH MONDAY MORNING FOR
NYZ038>041-043-047>054-058>061-063>066-082>084.
WINTER STORM WATCH FROM SATURDAY EVENING THROUGH MONDAY
MORNING FOR NYZ032-033-042.
MA...FLOOD WATCH FROM SATURDAY EVENING THROUGH MONDAY MORNING FOR
MAZ001-025.
VT...FLOOD WATCH FROM SATURDAY EVENING THROUGH MONDAY MORNING FOR
VTZ013>015.
&&
$$
SYNOPSIS...BGM
NEAR TERM...BGM
SHORT TERM...BGM
LONG TERM...HWJIV
AVIATION...FRUGIS
FIRE WEATHER...BGM/JPV
HYDROLOGY...BGM
FOR THE LATEST UPDATES...PLEASE VISIT OUR WEBPAGE AT
WWW.WEATHER.GOV/ALBANY
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1014 AM EDT FRI MAR 28 2014
.SYNOPSIS...
LOW PRESSURE MOVING ACROSS THE EASTERN GREAT LAKES TODAY WILL
PROVIDE MILD CONDITIONS AND SCATTERED AFTERNOON RAIN SHOWERS TO
SOUTHERN NEW ENGLAND. DRY WEATHER BRIEFLY RETURNS TONIGHT INTO
SATURDAY MORNING BEFORE A COASTAL STORM DEVELOPS SOUTH OF NEW
ENGLAND...BRINGING A CHILLY WINDSWEPT SOAKING RAIN TO THE REGION
SATURDAY NIGHT INTO SUNDAY. DRY WEATHER RETURNS AROUND TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
10 AM UPDATE...RAINFALL STARTING TO BECOME MORE WIDESPREAD ACROSS
NORTHWEST MA AND SOUTHWEST NH. TEMPERATURES ACROSS THAT REGION ARE
ALL ABOVE FREEZING NOW...ENDING THE THREAT OF FREEZING RAIN. AS
SUCH...ALLOWED THE WINTER WEATHER ADVISORY TO EXPIRE AT 10 AM.
OTHER THAN THAT...TWEAKED THE NEAR TERM FORECAST TO BETTER REFLECT
OBSERVED TRENDS. THROUGH THE 28/11Z RAP AND HRRR HAD A DECENT
HANDLE ON RAINFALL TIMING...AS DID THE 06Z NAM. INCORPORATED THOSE
SOURCES INTO THIS FORECAST UPDATE. WILL NEED TO KEEP AN EYE ON MAX
TEMPERATURES EARLY THIS AFTERNOON. NOW THAT THE WARM FRONT HAS
PUSHED NORTH...IF THE TIMING OF THICKER CLOUDS IS SLOWER THAN
CURRENT FORECAST THEN THOSE WILL NEED TO BE BUMPED HIGHER.
COVERAGE OF SHOWERS THIS AFTERNOON SHOULD BE SCATTERED SO NOT
EXPECTING A WASHOUT BY ANY MEANS.
AS SURFACE LOW MOVES NORTHEAST THROUGH THE ST LAWRENCE RIVER
VALLEY...WARM SECTOR OVERSPREADS SOUTHERN NEW ENGLAND WITH TEMPS
RISING WELL INTO THE 50S AND POSSIBLY NEAR 60 THIS AFTERNOON. THIS
IS COURTESY OF A STRONG LOW LEVEL SOUTHWEST JET OF 55-65 KT. THIS
WILL RESULT IN WINDY CONDITIONS ACROSS THE REGION WITH STRONGEST
WINDS PER BUFKIT NAM SOUNDINGS ACROSS NORTHEAST MA WITH GUSTS UP
TO 35 KT/40 MPH. NOT QUITE WIND ADVISORY CRITERIA BUT NEVERTHELESS
WINDY CONDITIONS. LESS MIXING ELSEWHERE WILL RESULT IN LOWER WIND
SPEEDS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
TONIGHT...
COLD FRONT SLIPS OFFSHORE ALONG WITH DEEP LAYER MOISTURE. COLUMN
BEGINS TO DRY YIELDING PARTIAL CLEARING ESPECIALLY NORTHERN MA AND
SOUTHWEST NH WITH MID TO HIGH CLOUDS ACROSS CT/RI AND SOUTHEAST MA.
POST FRONTAL AIRMASS NOT COLD AT ALL WITH MINS TONIGHT ONLY IN THE
U30S TO M40S...WARMER THAN NORMAL!
SATURDAY...
DRY TO START ALONG WITH SOME PARTIAL SUNSHINE ESPECIALLY NORTHERN MA
INTO SOUTHWEST NH. ALTHOUGH THIS WILL BE SHORT LIVED AS FRONTAL
BOUNDARY OFFSHORE BEGINS TO MOVE NORTHWARD AS LOW PRES DEVELOPS ON
THE FRONT OVER THE MID ATLC REGION. WARM CONVEYOR BELT RAINS BEGIN
TO MOVE NORTHWARD INTO CT/RI AND SOUTHEAST MA DURING MID TO LATE
AFTERNOON. GOOD MODEL AGREEMENT HERE ON TIMING ONSET OF PRECIP.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
* MORE SEASONABLE TEMPS EXPECTED THROUGH THE LONG TERM
* HEAVY RAIN LIKELY WITH COASTAL STORM THIS WEEKEND
THE 00Z MODELS ARE IN REASONABLY GOOD AGREEMENT ON THE SYNOPTIC
PATTERN. MAIN DIFFERENCES LIE IN THE EXACT TRACK AND SPEED OF A
FAIRLY STACKED SYSTEM MOVING OFF THE MID-ATLANTIC COAST AND
NORTHEASTWARD TOWARDS SOUTHERN NEW ENGLAND. THE 12Z ECMWF IS FASTER
AND A BIT FARTHER NORTH WHILE THE 00Z NAM IS SLOWER AND FARTHER
SOUTH. THE 00Z GFS IS A GOOD MIDDLE GROUND SOLUTION AND IS MORE IN
LINE WITH THE ENSEMBLE MEANS SO WILL LEAN MORE TOWARDS THE GFS TRACK
FOR THIS STORM. THIS COASTAL STORM WILL BE THE MAJOR FEATURE IN THE
LONG TERM WITH SIGNIFICANT IMPACTS ON SOUTHERN NEW ENGLAND THROUGH
THE WEEKEND AND INTO TUESDAY MORNING. THROUGHOUT THE REST OF THE
LONG TERM...A MID LEVEL RIDGE BUILDS OVER SOUTHERN NEW ENGLAND AND
QUIET...DRY WEATHER IS EXPECTED THROUGH THE MIDDLE OF THE WEEK.
SATURDAY NIGHT THROUGH MONDAY...LOW PRESSURE MOVES OFFSHORE NORTH
CAROLINA AND MOVES NORTHEAST TO NEAR THE 40/70 BENCHMARK. AS STATED
ABOVE...THERE ARE SOME DIFFERENCES IN THE MODELS BUT AM LEANING
TOWARDS THE GFS. ALL MODELS...INCLUDING THE ENSEMBLES...ARE
INDICATING A HIGH LIKELIHOOD OF 2 TO 4 INCHES OF RAIN ACROSS
SOUTHERN NEW ENGLAND. IN ADDITION...PWAT VALUES ARE 2 TO 3 STANDARD
DEVIATIONS ABOVE NORMAL...SO HEAVY RAIN IS LIKELY AT TIMES. DESPITE
HOW DRY ITS BEEN OVER THE LAST MONTH...JUST OVER AN INCH OF PRECIP
FOR THE MONTH OF MARCH...THIS AMOUNT OF RAIN OVER A 36 TO 48 HOUR
TIME FRAME IS LIKELY TO PRODUCE AT LEAST URBAN AND POOR DRAINAGE
FLOODING. RIVER BASINS HAVE A DECENT CAPACITY BECAUSE ITS BEEN
DRY...BUT WE WILL HAVE TO KEEP AN EYE ON THEM...PARTICULARLY IF WE
GET MORE THAN 2 TO 3 INCHES OF RAIN. WHILE MOST OF THE PRECIP IS
EXPECTED TO BE RAIN...AS THE LOW MOVES OUT TO SEA AND COOLER AIR
GETS DRAWN DOWN INTO THE REGION ON NORTHERLY FLOW...COULD SEE A
PERIOD OF WINTRY WEATHER MONDAY AS PRECIP COMES TO AN END. STILL
SOME UNCERTAINTY WITH THIS STORM SO WILL NEED TO KEEP AN EYE ON THE
MODEL TRENDS OVER THE NEXT DAY OR SO.
TUESDAY AND BEYOND...A MID LEVEL RIDGE BUILDS OVER THE NORTHEAST
WITH A HIGH LIKELIHOOD OF DRY WEATHER AND SEASONABLE TEMPERATURES.
THERE IS A LOW PROBABILITY OF SOME SHOWERS AS A COUPLE OF LOW
PRESSURE SYSTEMS MOVE THROUGH THE GREAT LAKES AND INTO QUEBEC.
&&
.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
FORECAST CONFIDENCE THIS PERIOD IS MODERATE TO HIGH. CIGS AND
VSBYS BASED ON AN EVEN BLEND OF NAM/MET/GFS/MAV DATA SETS.
REMAINDER OF THE FORECAST WAS A BLEND OF ALL MODEL GUIDANCE. WIND
FORECAST MORE WEIGHTED TOWARD HI RES NAM.
TODAY...VFR TO START WITH CIGS SLOWLY LOWERING TO MVFR THIS
AFTERNOON IN SCATTERED SHOWERS. MAIN ISSUE TODAY WILL BE GUSTY SW
WINDS THIS AFTERNOON. G35 KT POSSIBLE OVER EASTERN MA WITH
G25-30KT ELSEWHERE. LESS SURFACE WIND ALONG THE SOUTH COAST
INCLUDING CAPE COD WHICH WILL RESULT IN LLWS WITH SW WIND 50-60 AT
2 KFT.
TONIGHT...FRONT SLIPS SOUTH OF NEW ENGLAND. MVFR/IFR SOUTH COAST
IMPROVING TO VFR LATE. ELSEWHERE MVFR IMPROVES TO VFR. ANY
LINGERING RAIN SHOWERS ON THE SOUTH COAST MOVE OFFSHORE LATER IN
THE EVENING.
SATURDAY...VFR AND DRY TO START BUT THEN LOWERING TO MVFR AS RAIN
OFF THE SOUTH COAST COMES ONSHORE LATER IN THE AFTERNOON FROM
SOUTH TO NORTH.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF. SW WINDS MAY GUSTS UP TO
35-40 KT THIS AFTERNOON.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK...SATURDAY NIGHT THROUGH TUESDAY...
SATURDAY NIGHT THROUGH MONDAY...MODERATE CONFIDENCE. AREAS OF MVFR
CIGS/VSBYS IN HEAVY RAIN/FOG. A WINTRY MIX IS POSSIBLE LATE SUNDAY
NIGHT INTO MONDAY AS PRECIP COMES TO AN END.
TUESDAY...MODERATE TO HIGH CONFIDENCE. IMPROVING CONDITIONS AS RAIN
MOVES OUT OF THE REGION.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
MODERATE TO HIGH FORECAST CONFIDENCE THRU SAT NIGHT.
TODAY...
INCREASING SW WINDS AS COLD FRONT APPROACHES FROM THE WEST. SW WINDS
GUSTS TO 25-30 KT WITH STRONGEST WIND NEAR SHORE GIVEN WARM LAND
TEMPS. MODERATE RISK OF GUSTS 35-40 KT NORTH OF PLYMOUTH TO CAPE ANN
THIS AFTERNOON. THUS HAVE ISSUED A GALE WARNING FOR THIS AREA AND
SCA FOR ALL OTHER WATERS. SCATTERED RAIN SHOWERS.
TONIGHT...
COLD FRONT SLIPS OFFSHORE WITH WINDS DIMINISHING AND SHIFTING FROM
SW TO WNW BY MORNING.
SATURDAY...
WARM FRONT LIFTS NORTH WITH INCREASING SOUTH WINDS ACROSS THE SOUTH
OCEAN WATERS. RAIN ALSO OVERSPREADS SOUTHERN WATERS.
OUTLOOK...SATURDAY NIGHT THROUGH TUESDAY...
SATURDAY NIGHT THROUGH MONDAY...LOW TO MODERATE CONFIDENCE. GALE
WARNINGS WILL LIKELY BE NEEDED FOR SOME OF THE COASTAL WATERS AS LOW
PRESSURE MOVES OVER THE WATERS. SEAS INCREASE TO 10 TO 15 FEET ON
THE OUTER WATERS. VISIBILITIES WILL LIKELY BE LIMITED AT TIMES IN
HEAVY RAIN AND FOG.
TUESDAY...WINDS AND SEAS DIMINISH AS WEAK HIGH PRESSURE BEGINS TO
BUILD OVER THE WATERS.
&&
.TIDES/COASTAL FLOODING...
INCREASING SPRING TIDE WILL BE OCCURRING OVER THIS WEEKEND WITH
TIDES REACHING BETWEEN 11.2 AND 11.5 AT HIGH TIDE IN BOSTON. AS A
COASTAL STORM AFFECTS THE REGION OVER THE WEEKEND...WINDS WILL
GENERALLY BE IN A NORTHERLY TO NORTHEASTERLY DIRECTION. WITH THESE
WIND DIRECTIONS EXPECT THE MOST VULNERABLE COASTLINES WILL BE THE
NORTH FACING BEACHES OF CAPE COD AS WELL AS NANTUCKET.
HOWEVER...WITH THE EXPECTED STRENGTH OF THE WINDS AND AN UNCERTAIN
TRACK...COASTAL FLOODING IS POSSIBLE ALONG THE ENTIRE EAST COAST OF
MASSACHUSETTS. BEACH EROSION IS A CONCERN AS WELL GIVEN MULTIPLE
TIDE CYCLES WILL BE IMPACTED. THE MOST LIKELY TIDE CYCLES TO
RESULT IN FLOODING ARE THE SUNDAY NIGHT HIGH TIDE AND POSSIBLY THE
MONDAY MIDDAY HIGH TIDE.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EDT SATURDAY FOR ANZ231>234.
GALE WARNING UNTIL 10 PM EDT THIS EVENING FOR ANZ230-251.
SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR ANZ236.
SMALL CRAFT ADVISORY UNTIL 6 AM EDT SATURDAY FOR ANZ235-237-
250-254>256.
&&
$$
SYNOPSIS...NOCERA/RLG
NEAR TERM...BELK/NOCERA/RLG
SHORT TERM...NOCERA
LONG TERM...DUNTEN
AVIATION...NOCERA/DUNTEN
MARINE...NOCERA/DUNTEN
TIDES/COASTAL FLOODING...STAFF
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
332 PM EDT FRI MAR 28 2014
.DISCUSSION...
...ROUND OF STORMS OVERNIGHT WITH HEAVY RAIN AND GUSTY WINDS...
TONIGHT...MCS MOVING OFF THE LA COAST AND FL PANHANDLE THIS
AFTERNOON. CONVECTION PROPAGATING SOUTH INTO GREATER INSTABILITY
BUT AWAY FROM BEST MID/UPPER LVL WIND FIELD. SHORT RANGE
GUIDANCE...HRRR RAP AND LOCAL ARW SHOW MCS OR REDEVELOPED
CONVECTION ALONG ITS OUTFLOW BNDRY PUSHING INTO NRN PORTIONS OF
FCST AREA OVERNIGHT...MAINLY AFTER MIDNIGHT. GUIDANCE ALSO
RELATIVELY CONSISTENT IN WEAKENING CONVECTION OVERALL ONCE MCS
GETS AWAY FROM STRONG FORCING PROVIDED BY COUPLED UPPER JET
MCS FEATURE IS UNDER INFLUENCE CURRENTLY. STILL...ACTVTY WILL HAVE
25-30KT H8 WINDS AT ITS DISPOSAL AND CONVECTIVE DOWNDRAFTS WILL HAVE
POTENTIAL FOR STRONG WIND GUSTS. STRONGEST STORMS WILL BE ACROSS
NORTHERN SECTIONS. HAVE INTRODUCED MORE OF A PCPN GRADIENT FROM
NORTH TO SOUTH BASED ON CURRENT MDL TRENDS.
SATURDAY...PLENTY OF LYRD CLOUDINESS WILL BE ACROSS AREA WITH SCT
SHRA IN THE MORNING. ATMOSPHERE WILL BE SLOW TO REGROUP INTO
DIURNAL PHASE DUE TO LOSS OF HEATING WITH EXTENSIVE CLOUD COVER.
MODELS MUCH LESS IN AGREEMENT IN THIS TIME PERIOD IN PART DUE TO
CONVECTIVE DEBRIS AND LOCATION OF RESIDUAL VORT ASSCD WITH OLD
MCS. SFC FRONT WILL APPROACH AREA FROM NORTH LATE IN DAY AS SFC
LOW RAPIDLY INTENSIFIES OVER THE MID ATLC. HAVE LARGELY GONE WITH
GFS POPS...HIGH CHC AREA WIDE...BUT HAVE GONE WELL BELOW GUIDANCE
TEMPS DUE TO AFOREMENTIONED CLOUDS.
SAT NIGHT-SUN...UPPER LEVEL LOW SWINGS THROUGH THE EAST COAST
OVERNIGHT SAT DRIVING THE PARENT LOW OFF THE MID-ATLANTIC COAST AND
THE ASSOCIATED COLD FRONT THROUGH THE FLORIDA PENINSULA. SCATTERED
SHOWERS AND A FEW THUNDERSTORMS POSSIBLE IN THE EVENING AHEAD OF THE
ACTUAL FRONT...THOUGH HOW MUCH ACTIVITY THAT OCCURS DURING THE DAY
MAY AFFECT STABILITY INTO THE EVENING HOURS.
PRECIPITATION TAPERING OFF TOWARDS DAYBREAK WITH MOSTLY SUNNY SKIES
AND DRY CONDITIONS FOR SUNDAY.
MIN TEMPS SAT NIGHT WILL BE IN THE MID 50S NORTH TO UPPER 60S/LOW
70S AROUND LAKE OKEECHOBEE/TREASURE COAST WHERE FRONT WILL JUST BE
CLEARING AROUND SUNRISE SUN.
BREEZY NORTHWEST WINDS ON SUN WILL BRING MAX TEMPS DOWN A FEW
DEGREES FROM SAT INTO SEASONABLE MID-UPPER 70S.
FROM PREVIOUS DISCUSSION
MON-NEXT FRI...HIGH PRESSURE CENTER SHOULD DROP INTO NORTH FLORIDA
MON THEN ONLY GRADUALLY SLIDE SEAWARD INTO LATE WEEK. ONSHORE FLOW
WILL COMMENCE BUT ONLY SLOWLY MODIFY THE INITIALLY VERY DRY AIR
MASS. THE 00Z GFS INDICATED IT REMAINING DRY ENOUGH TO PRECLUDE
POPS THROUGH THE PERIOD. WITH THE HIGH PRESSURE NEARBY MON MORNING
TEMPS LOOK A LITTLE BELOW NORMAL...THEN A GRADUALLY MODERATION TO
A LITTLE ABOVE NORMAL IS INDICATED.
&&
.AVIATION...
MAINLY VFR CONDITIONS OVERNIGHT WITH EXCEPTION OF PERIOD OF
CONVECTIVE ACTVTY MOVING ACROSS MOST LOCATIONS OVERNIGHT. WILL
RESULT IN 2-3 HOUR PERIOD OF MVFR OR IFR CONDITIONS WITH BRIEF HVY
RAIN AND GUSTY WINDS.
&&
.MARINE...
TONIGHT-SAT...WIND SPEEDS HAVE DROPPED BLO SCA AS RIDGE BUIDLS TO
THE EAST. SEAS WILL SUBSIDE GDLY WITH SCEC TO FOLLOW SCA ENDING
LATE THIS AFTN. SOME STRONG STORMS WITH GUSTY WINDS TO MOVE
OFFSHORE TONIGHT AND AGAIN ON SATURDAY.
SUN...COLD FRONT PUSHES THROUGH THE WATERS SAT NIGHT WITH WINDS
BECOMING NE AROUND 20KTS BY DAYBREAK SUN WITH UP TO 25KTS WITH
INITIAL SURGE ESPECIALLY OVER OFFSHORE WATERS NORTH OF SEBASTIAN
INLET. WINDS DIMINISH THROUGH THE DAY ON SUN AS HIGH PRESSURE SLIDES
INTO THE EASTERN US WITH NW WINDS BECOMING 15KTS BY THE AFTERNOON
AND NORTH 10-15KTS OVERNIGHT.
WIND DIRECTION WILL HELP BUILD SEAS OFFSHORE...WITH 6-8FT BY LATE
MORN AND 4-6FT CLOSER TO THE COAST.
MON-TUE...SURFACE HIGH CENTER SLIDES OVER CENTRAL PENINSULA DURING
THE DAY ON MONDAY AND OFFSHORE TUE WILL CAUSE WINDS TO VEER TO THE
NORTHEAST/EAST ON MON AND THEN TO THE EAST ON TUE. SPEEDS LOOK CLOSE
TO 10 KNOTS EXCEPT MAYBE 10-15 KNOTS IN THE SOUTH ON MON. SEAS
INITIALLY 4-6FT OFFSHORE ON MON DIMINISHING 2-4FT BY TUES.
&&
.FIRE WEATHER...
SUN-TUE...POST-FRONTAL NORTHWEST FLOW WILL BRING IN A MUCH DRIER
AIRMASS FOR SUNDAY WITH MIN RH VALUES BELOW 30 PERCENT FOR MOST OF
EAST CENTRAL FLORIDA. SUSTAINED WINDS WILL GENERALLY BE AROUND
10-15MPH...THOUGH OCCASIONAL HIGHER GUSTS WILL BE POSSIBLE EARLIER
IN THE DAY. MIN RH IS FORECAST BELOW 35 PERCENT IN THE NORTH
INTERIOR ON MON...BUT NORTHEAST/EAST WINDS WILL DROP OFF BELOW 10
MPH.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 67 82 58 75 / 70 50 40 0
MCO 67 83 61 77 / 60 50 30 0
MLB 70 83 65 76 / 60 50 40 0
VRB 66 83 67 76 / 60 50 40 10
LEE 66 82 58 75 / 70 50 30 0
SFB 68 83 60 77 / 70 50 30 0
ORL 68 83 60 76 / 70 50 30 0
FPR 70 83 69 76 / 50 50 40 10
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...LAKE WIND ADVISORY UNTIL 7 PM EDT THIS EVENING FOR COASTAL
VOLUSIA-INDIAN RIVER-INLAND VOLUSIA-MARTIN-NORTHERN BREVARD-
NORTHERN LAKE-OKEECHOBEE-ORANGE-OSCEOLA-SEMINOLE-SOUTHERN
BREVARD-SOUTHERN LAKE-ST. LUCIE.
AM...SMALL CRAFT ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR COASTAL
WATERS FROM SEBASTIAN INLET TO JUPITER INLET OUT 20 NM-
COASTAL WATERS FROM VOLUSIA BREVARD COUNTY LINE TO
SEBASTIAN INLET OUT 20 NM-WATERS FROM FLAGLER BEACH TO
VOLUSIA BREVARD COUNTY LINE 20 TO 60 NM OFFSHORE-WATERS
FROM SEBASTIAN INLET TO JUPITER INLET 20 TO 60 NM OFFSHORE-
WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET
20 TO 60 NM OFFSHORE.
&&
$$
SHORT TERM/AVIATION...BLOTTMAN
LONG TERM....MOSES
AREA FORECAST DISCUSSION
NWS MIAMI FL
132 PM EDT FRI MAR 28 2014
.AVIATION...
KEPT THE FORECAST VFR THROUGH THE PERIOD AS CURRENT THINKING IS
THAT ANY LOWER CONDITIONS WILL BE LATE SATURDAY MORNING OR DURING
THE AFTERNOON. THE ONLY EXCEPT IS THAT THE HRRR DOES SHOW THE LINE
OF CONVECTION CURRENTLY IN THE FL PANHANDLE TO APPROACH LAKE
OKEECHOBEE AFT 04Z THIS EVENING AND THIS COULD BRING SOME SHRA
EARLIER THAN IN THE FORECAST ESPECIALLY AT APF AND PBI.
INSTABILITY WILL BE ON THE INCREASE TOO ON SATURDAY BUT MOST OF
THE THUNDER THREAT APPEARS TO BE AFT 18Z. SURFACE WIND WILL SLOWLY
DIMINISH THIS AFTERNOON AND THEN VEER TO A S-SSW DIRECTION EARLY
SATURDAY AS THE COLD FRONT APPROACHES.
KOB
&&
.PREV DISCUSSION... /ISSUED 927 AM EDT FRI MAR 28 2014/
UPDATE...
THE ONLY CHANGE MADE TO THE FORECAST WAS TO LOWER POPS THIS
MORNING ACROSS THE REGION. LOW LEVEL MOISTURE WILL START TO
INCREASE THIS AFTERNOON ALLOWING FOR A BETTER CHANCE OF SHOWERS. A
THUNDERSTORM OR TWO CANNOT BE RULED OUT AS WELL MAINLY NEAR LAKE
OKEECHOBEE. CHANCES OF SHOWERS WILL CONTINUE TO INCREASE TONIGHT
OUT AHEAD OF AN APPROACHING COLD FRONT.
PREV DISCUSSION... /ISSUED 732 AM EDT FRI MAR 28 2014/
AVIATION...
MAIN CONCERN TODAY WILL BE GUSTY SOUTHEAST SURFACE WIND TO
OCCASIONALLY OVER 20 KNOTS ALONG THE EAST WITH GRADIENT TOO STRONG
FOR A WEST COAST SEA BREEZE. VFR CONDITIONS WILL PREVAIL WITH A
FEW SHOWERS FROM TIME TO TIME BUT NOT ENOUGH COVERAGE FOR OTHER
THAN VCSH IN THE FORECAST.
KOB
PREV DISCUSSION... /ISSUED 404 AM EDT FRI MAR 28 2014/
DISCUSSION...
HIGH PRESSURE ACROSS THE WESTERN ATLANTIC WILL CONTINUE TO RETREAT
FURTHER TO THE NORTHEAST AND AWAY FROM THE FLORIDA PENINSULA THROUGH
THE DAY. THIS WILL ALLOW A DEEPER MOISTURE AXIS TO PUSH INTO THE
AREA WELL AHEAD OF A DEVELOPING AREA OF LOW PRESSURE ACROSS
SOUTHEAST TEXAS. THIS MEANS INCREASING SHOWER CHANCES ACROSS THE
AREA THIS AFTERNOON. A FEW THUNDERSTORMS MAY ALSO BE POSSIBLE MAINLY
ACROSS THE LAKE OKEECHOBEE REGION AS A FEW MID LEVEL IMPULSES PASS
BY. PRECIPITATION COVERAGE IS EXPECTED TO INCREASE TONIGHT OUT AHEAD
OF AN APPROACHING COLD FRONT IN THE CENTRAL GULF OF MEXICO. THE
ECMWF CURRENTLY DEPICTS LESS QPF OUTPUT THAN THE GFS...SO WENT WITH
A COMPROMISE FOR NOW WITH REGARD TO POPS THROUGH THE NIGHT.
BY SATURDAY A HIGHLY AMPLIFIED H5 SHORTWAVE WILL DIG SOUTHEAST
ACROSS THE MISSISSIPPI VALLEY AND INTO THE APPALACHIANS. AS IT
DOES...ITS ASSOCIATED SURFACE LOW WILL DEEPEN AND PUSH NORTHEAST AND
INTO THE OHIO VALLEY. THIS WILL PUSH THE COLD FRONT ACROSS THE
FLORIDA PENINSULA LATE SATURDAY AND INTO SUNDAY WITH ADDITIONAL
SHOWERS AND THUNDERSTORMS POSSIBLE. CONVECTIVE PARAMETERS CONTINUE
TO LOOK MEAGER WITH THIS SYSTEM AND BETTER DYNAMICS WILL BE WELL
NORTH OF THE AREA. ALSO THE FRONTAL PASSAGE LOOKS TO TAKE PLACE
OVERNIGHT SATURDAY INTO SUNDAY WHICH WOULD ALSO BE UNFAVORABLE FOR
ANY STRONG THUNDERSTORM DEVELOPMENT.
THE FRONT AND ALL ASSOCIATED PRECIPITATION SHOULD EXIT THE AREA BY
MIDDAY SUNDAY GIVING WAY TO DRIER AND MUCH MORE MILD TEMPERATURES
UNDER NORTHERLY FLOW. HIGH PRESSURE WILL THEN DOMINATE THROUGH MOST
OF THE UPCOMING WEEK WITH CONTINUED DRY CONDITIONS AND NEAR NORMAL
TEMPERATURES.
THE GFS HINTS AT ANOTHER FRONT APPROACHING SOUTH FLORIDA BY THE END
OF NEXT WEEK BRINGING ANOTHER ROUND OF SHOWERS BUT THE ECMWF KEEPS
DRY UPPER RIDGING AND SOUTHEAST FLOW.
AVIATION...
VFR WITH BREEZY CONDITIONS ARE EXPECTED TO CONTINUE THROUGH THE DAY
AS THE PRESSURE GRADIENT OVER SOUTH FLORIDA CONTINUES TO REMAIN
TIGHT BETWEEN A HIGH TO THE ENE AND A LOW DEVELOPING OVER TEXAS.
WITH THE FLOW SOUTHEASTERLY AND PLENTY OF MOISTURE IN THE
ATMOSPHERE, THERE WILL BE A CHANCE OF SHOWERS. HOWEVER, THERE IS
HIGH UNCERTAINTY WITH THE COVERAGE AND LOCATION. BEST GUESS IS MORE
IN THE LAKE REGION AND NORTH, INTO CENTRAL FLORIDA. SO, NO MENTION
OF RAIN IN THE TAFS AT THIS TIME, ALTHOUGH THERE IS STILL A SLIGHT
POSSIBILITY OF A SHOWER AT A TAF SITE THIS AFTERNOON, ESPECIALLY
KPBI AND EVEN KAPF.
MARINE...
GUSTY SOUTHEASTERLY WINDS WILL CONTINUE ACROSS THE ATLANTIC
WATERS THROUGH THE MORNING WITH 6 TO 8 FOOT SEAS. FLOW WILL THEN
BECOME MORE SOUTHERLY AND THEN SOUTHWESTERLY BY SATURDAY AS A
COLD FRONT APPROACHES. THIS WILL ALLOW SEAS TO DIMINISH
CONSIDERABLY. WINDS AND SEAS WILL THEN QUICKLY INCREASE AGAIN
BEHIND THE FRONT ON SUNDAY INTO MONDAY.
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR FLZ168-172-
173.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
406 PM EDT FRI MAR 28 2014
.SYNOPSIS...
AN AREA OF LOW PRESSURE WILL DEVELOP TO THE WEST TONIGHT...PUSHING
A COLD FRONT TOWARD THE REGION. THE COLD FRONT WILL CROSS THE AREA
SATURDAY EVENING...FOLLOWED BY DRY HIGH PRESSURE INTO NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
REST OF THE AFTERNOON AND TONIGHT...THE ONGOING COVERAGE OF SHOWERS
CONTINUES TO FAVOR MOSTLY SOUTHEAST GEORGIA AND THE FAR EASTERN AREA
INCLUDING THE COASTAL WATERS AND EASTERN CHARLESTON COUNTY.
CONVECTION CONTINUES TO BE QUITE SHALLOW THANKS TO THE MID LEVEL
SUBSIDENCE INVERSION NOTED IN THE MORNING SOUNDING. LOOKING AT
REGIONAL RADAR IMAGERY...THE HRRR CONTINUES TO BE THE MODEL BEST
HANDLING THE ONGOING DEEPER CONVECTION ALONG THE GULF AND THE SHOWER
ACTIVITY ACROSS THE FORECAST AREA. IT KEEPS SHOWERS GOING ACROSS THE
FORECAST AREA INTO THE EARLY PART OF THE OVERNIGHT ASSOCIATED WITH A
PASSING MID LEVEL SHORTWAVE NOTED IN WATER VAPOR IMAGERY. I HAVE
THEREFORE CONTINUED TO CARRY LIKELY TO CATEGORICAL POPS TO THE WEST
OVER THE NEXT FEW HOURS...WITH A BAND OF LIKELY AND HIGH CHANCE POPS
MOVING ACROSS FROM WEST TO EAST THROUGH LATE TONIGHT. THE MODELS ARE
PERSISTENT IN SHOWING AN AREA OF IMPROVED MID LEVEL LAPSE RATES AND
NEGATIVE SHOWALTER INDICES NOSING IN FROM THE WEST...SO ELEVATED
CONVECTION REMAINS A POSSIBILITY. A SLIGHT CHANCE OF THUNDER
CONTINUES IN THE FORECAST. BY SATURDAY MORNING...IT APPEARS WE WILL
BE IN A BIT OF A LULL FOR PRECIPITATION. THE MID/UPPER LEVELS BEGIN
TO DRY OUT A BIT AND WE MAY EVEN SEE A BRIEF PERIOD OF SOME NVA
ALOFT IN THE WAKE OF THE DEPARTING SHORTWAVE. THE GENERAL FLOW
REGIME WILL CONTINUE TO BE SOUTHERLY IN THE LOW LEVELS AHEAD OF THE
APPROACHING FRONT. THIS WILL RESULT IN A MILD AND MOIST NIGHT IN THE
ONSHORE FLOW. EXPECT LOWS ONLY IN THE LOW TO MID 60S. ALSO...I HAVE
ADDED PATCHY FOG EVERYWHERE OVERNIGHT. THERE WILL LIKELY BE ENOUGH
SURFACE LEVEL FLOW TO PREVENT FOG FROM BECOMING TOO WIDESPREAD...SO
PATCHY FOG SHOULD COVER IT.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
PRIMARY FORECAST ATTENTION FOCUSES ON THE POTENTIAL FOR SEVERE
WEATHER SATURDAY. STARTED THE DAY WITH CHANCE POPS AS MORE
WIDESPREAD SHOWERS SHOULD HAVE EXITED TO THE E/NE. THEN...POPS RAMP
UP TO LIKELY BY EARLY/MID AFTERNOON AS AN AMPLIFYING UPPER
TROUGH/ASSOCIATED COLD FRONT APPROACH THE REGION FROM THE WEST.
FORCING FOR ASCENT AHEAD OF THESE FEATURES...INCLUDING HEIGHT FALLS
AND UPPER DIVERGENCE...700-500 LAPSE RATES EXCEEDING 6 C/KM AND
SUB-ZERO SHOWALTER INDICES AND 0-6 KM BULK SHEAR 40-50 KNOTS ALL
SUGGEST THE POTENTIAL FOR ONE OR MULTIPLE BANDS OF PRE-FRONTAL
CONVECTION PUSHING THROUGH THE REGION WITH AT GUSTY WINDS AND
LOCALLY HEAVY RAINFALL SATURDAY AFTERNOON/EVENING. FORECAST
UNCERTAINTY CENTERS ON THE AMOUNT OF INSOLATION/WARMING AND
ASSOCIATED DEGREE OF SURFACE-BASED INSTABILITY AHEAD OF THE COLD
FRONT. THE 28/12Z NAM SUGGESTS THAT CLOUDS/PRECIPITATION WILL LIMIT
INSTABILITY...AND THE RESULTING SEVERE THREAT WILL REMAIN LIMITED TO
ISOLATED/BRIEF DAMAGING WIND GUSTS. ON THE OTHER HAND...IF
AGGRESSIVE DRY SLOTTING BREAKS UP CLOUDS AND ALLOWS TEMPS TO RECOVER
TO AROUND 80F AS SUGGESTED BY 28/12Z GFS AND EURO
SOLUTIONS...RESULTING SURFACE BASED CAPE 1000-1800 J/KG WILL COMBINE
WITH FAVORABLE KINEMATIC PARAMETERS/SYNOPTIC FORCING TO SUPPORT A
MORE SIGNIFICANT SEVERE WEATHER THREAT...PERHAPS IN THE FORM OF AN
AFTERNOON/EARLY EVENING SQUALL LINE PRODUCING DAMAGING WIND GUSTS
AND EVEN SOME LARGE HAIL/AN ISOLATED TORNADO.
THE COLD FRONT AND ASSOCIATED PRECIPITATION WILL PUSH OFFSHORE
SATURDAY NIGHT. POPS RAMP DOWN STEADILY FROM CHANCE/LIKELY EARLY TO
VIRTUALLY ZERO PERCENT LATE. A SURGE OF COOLER DRIER AIR...DRIVEN BY
GUSTY NORTHWEST WINDS...WILL PUSH TEMPERATURES INTO THE MID/UPPER
40S AT MOST LOCATIONS BY SUNDAY MORNING.
BETWEEN DEEPENING LOW PRESSURE EXITING THE MID ATLANTIC COAST AND
HIGH PRESSURE BUILDING FROM THE W/NW...SUNDAY WILL FEATURE BREEZY
AND DRY CONDITIONS ACCOMPANIED BY TEMPERATURES IN THE UPPER 60S TO
LOWER 70S...JUST A SHADE BELOW NORMAL FOR LATE MARCH.
AS HIGH PRESSURE SHIFTS EAST AND WINDS DIMINISH SUNDAY
NIGHT...RADIATIONAL COOLING WILL SUPPORT LOW TEMPS IN THE LOWER TO
MID 40S MOST LOCATIONS. WELL INLAND...THE COOLEST LOCATIONS COULD
BOTTOM OUT IN THE UPPER 30S...BUT THE PROBABILITY FOR ANY FROST WILL
REMAIN VERY LOW.
MONDAY...UNDER HIGH PRESSURE TEMPERATURES WILL RECOVER INTO AT LEAST
THE MID 70S AWAY FROM THE BEACHES. A SEA BREEZE WILL DEVELOP AND
WILL PUSH INLAND MONDAY AFTERNOON.
LAKE WINDS...GUSTY WINDS AND CHOPPY WAVES COULD DEVELOP ON LAKE
MOULTRIE...ESPECIALLY SATURDAY NIGHT AND SUNDAY. A LAKE WIND
ADVISORY COULD EVENTUALLY BE REQUIRED.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A BROAD UPPER LEVEL RIDGE WILL PREVAIL MONDAY NIGHT THROUGH THURSDAY
WITH DRY HIGH PRESSURE AT THE SURFACE. THIS WILL RESULT IN ABOVE
NORMAL TEMPERATURES WITH HIGHS CLIMBING INTO THE UPPER 70S OR LOWER
80S AND LOWS MAINLY IN THE 50S. THE UPPER RIDGE BREAKS DOWN ON
FRIDAY WITH A WEAK COLD FRONT POSSIBLY MOVING IN FROM THE WEST.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
EXPECT UNSETTLED CONDITIONS THROUGH 18Z SATURDAY. SCATTERED TO
NUMEROUS SHOWERS HAVE DEVELOPED NEAR THE TERMINALS THIS AFTERNOON
SO A VCSH HAS BEEN ADDED. ALSO...TO ACCOUNT FOR DIRECT
IMPACTS...MVFR CONDITIONS HAVE BEEN ADDED IN A TEMPO GROUP THAT
RUNS THROUGH LATE AFTERNOON MAINLY FOR CEILINGS BUT ALSO FOR
VISIBILITIES AS RAINFALL BRIEFLY BECOMES MODERATE. THERE IS A LOW
CHANCE FOR A RUMBLE OF THUNDER...BUT THE PROBABILITY IS TOO LOW TO
INCLUDE IN THE FORECAST. THIS EVENING AND THROUGH THE OVERNIGHT...IT
IS BECOMING INCREASINGLY LIKELY THAT WIDESPREAD MVFR CEILINGS WILL
DEVELOP. I HAVE TIMED THIS INTO KSAV AT 00Z AND INTO KCHS AT 03Z.
WE WILL LIKELY SEE ADDITIONAL PERIODS OF SHOWERS AT BOTH SITES
LATE THIS EVENING BEFORE THIS AREA OF PRECIPITATION PUSHES OFF TO
THE EAST LATE. GUIDANCE CONTINUES TO INDICATE A LOW TO MODERATE
CHANCE OF IFR CONDITIONS LATE TONIGHT. PROBABILITIES ARE HIGHEST
AT KSAV...BUT I/M NOT READY TO COMMIT TO PREVAILING IFR THIS FAR
OUT. I HAVE TRENDED KSAV DOWN INTO THE LOW END MVFR RANGE STARTING
AT 06Z AND CONTINUING THROUGH THE MID MORNING. CEILINGS SHOULD
LIFT TO LOW END VFR MID/LATE SATURDAY MORNING. A COLD FRONT AND AN
INCREASING POTENTIAL FOR THUNDERSTORMS ALONG IT WILL APPROACH
SATURDAY AFTERNOON. SHOWERS OUT AHEAD OF THE FRONT WILL DEVELOP
FIRST AT KSAV AND WINDS WILL BEGIN TO PICK UP AND BE GUSTY OUT OF
THE SOUTH. THIS WILL ALSO HAPPEN AT KCHS...THOUGH LATER...AND HAS
NOT BEEN INCLUDED AT THIS TIME.
EXTENDED AVIATION OUTLOOK...OCCASIONAL FLIGHT RESTRICTIONS POSSIBLE
SATURDAY AFTERNOON AND EVENING IN SHOWERS/SCATTERED THUNDERSTORMS.
VFR CONDITIONS EXPECTED THEREAFTER. BREEZY CONDITIONS EXPECTED
SATURDAY NIGHT THROUGH SUNDAY.
&&
.MARINE...
REST OF THE AFTERNOON AND TONIGHT...PERSISTENT SOUTHEASTERLY FLOW
HAS CONTINUED TODAY BETWEEN THE HIGH OVER THE OPEN ATLANTIC AND THE
COLD FRONT TO THE WEST. THE COOL SEA SURFACE TEMPERATURES...ESPECIALLY
OVER THE SHELF WATERS...HAS PREVENTED WINDS FROM GETTING MUCH
STRONGER THAN 10 TO 15 KT THUS FAR. ONE SURPRISE HAS BEEN THE
RAPID INCREASE IN SEAS...PRIMARILY COMPRISED OF A 7 SECOND SWELL.
41008 HAS REPORTED SEAS UP TO ALMOST 8 FT AND 41008 IS NOW
REACHING TO AROUND 5 FT. DUE TO THESE OBSERVATIONS WE HAVE HOISTED
A SMALL CRAFT ADVISORY FOR THE OUTER GEORGIA WATERS THAT STARTS
NOW AND RUNS THROUGH THE NIGHT. 6 FT SEAS ARE EXPECTED TO DRAW
CLOSER TO SHORE AND BEGIN GET INTO THE NEARSHORE WATERS ALONG THE
CHARLESTON COUNTY COAST AFTER MIDNIGHT. A SMALL CRAFT ADVISORY HAS
BEEN INITIALIZED AT THAT TIME AND RUNS INTO SATURDAY.
OVERALL...WINDS WILL REMAIN IN THE 10-15 KT RANGE...PERHAPS UP TO
20 KT BEYOND 20 NM...THOUGH TONIGHT IN THE SOUTHERLY FLOW. ANOTHER
CONCERN IN THE MOIST SOUTHERLY FLOW IS THE POTENTIAL FOR SEA FOG
TO DEVELOP OVERNIGHT. I HAVE ADDED PATCHY FOG AFTER MIDNIGHT AS A
RESULT.
CONDITIONS WILL REMAIN FAVORABLE FOR SEA FOG UNTIL A COLD FRONT
CROSSES THE WATERS WITH MUCH DRIER AIR SATURDAY EVENING. THE
FORECAST INDICATES PATCHY FOG...BUT MORE WIDESPREAD FOG COULD PROMPT
DENSE FOG ADVISORIES.
SATURDAY THROUGH TUESDAY...ELEVATED SEAS WILL PERSIST...AND SOUTHERLY
WINDS WILL INCREASE TO 15-20 KT...WITH GUSTS TO 25 KT POSSIBLE
BEYOND 20 NM...AHEAD OF AN APPROACHING COLD FRONT. AFTER COLD
FROPA...SMALL CRAFT ADVISORY NORTHWEST WINDS/HAZARDOUS SEAS WILL
PREVAIL THROUGH SUNDAY. W/NW WINDS WILL GRADUALLY DIMINISH SUNDAY
NIGHT...AND HIGH PRESSURE WILL SHIFT OVER THE WATERS AND WILL
PROVIDE MUCH LIGHTER WINDS AND SUBSIDING SEAS MONDAY-TUESDAY.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 10 AM SATURDAY TO 5 PM EDT SUNDAY
FOR AMZ352.
SMALL CRAFT ADVISORY UNTIL 11 PM EDT SUNDAY FOR AMZ374.
SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 5 PM EDT SUNDAY
FOR AMZ350.
&&
$$
SYNOPSIS...
NEAR TERM...BSH
SHORT TERM...SPR
LONG TERM...JRL
AVIATION...BSH/SPR
MARINE...BSH/SPR
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
246 PM EDT FRI MAR 28 2014
.PREV DISCUSSION... /ISSUED 1040 AM EDT FRI MAR 28 2014/
UPDATE...
HAVE MADE SIGNIFICANT ADJUSTMENTS TO THE FORECAST TO ACCOUNT FOR
LATEST THINKING WITH TODAYS WEATHER. AXIS OF PRECIPITATION IS
FURTHER SOUTH THAN ORIGINALLY ANTICIPATED...AND PREVIOUS FORECAST
POP AND WX GRIDS DID NOT MATCH THIS POSITIONING.
OVERALL...MODEL GUIDANCE WITH THIS SYSTEM IS POOR...WITH VERY FEW
DEPICTING THE CURRENT RADAR TRENDS WELL. HAVE OVERALL GONE WITH
THE HRRR WHICH SEEMS TO HAVE A BETTER HANDLE ON THE CURRENT
CONDITIONS. THE HRRR DOES SUGGEST MUCH OF THE COMPLEX IN MS/AL
WILL ORGANIZE INTO THIS AFTERNOON...BECOMING MORE LINEAR IN
NATURE...AND PUSHING ACROSS SOUTHWEST GEORGIA. ALTHOUGH THERE IS A
QUESTION OF WHETHER THIS LINEAR CONVECTION WILL MATERIALIZE...THE
HRRR CONTINUES TO SHOW MUCH OF NORTH GEORGIA CUT OFF FROM GULF
MOISTURE...AND LIMITS THE AMOUNT OF PRECIP OVER THE NORTHERN
SECTIONS OF THE CWA. AS A RESULT...HAVE CONTINUED THE TREND OF
HIGHEST POPS ACROSS CENTRAL GEORGIA INTO THE OVERNIGHT PERIOD.
WILL CONTINUE TO UPDATE THE GRIDS AS NECESSARY...ESPECIALLY THE
NEXT 24 HOURS.
31
PREV DISCUSSION... /ISSUED 717 AM EDT FRI MAR 28 2014/
PREV DISCUSSION... /ISSUED 341 AM EDT FRI MAR 28 2014/
SHORT TERM /TODAY THROUGH SATURDAY/...
SURFACE ANALYSIS SHOWS A COLD FRONT STRETCHING FROM THE CENTRAL
GREAT LAKES BACK THROUGH THE ARKLATEX. A LARGE AREA OF PRECIPITATION
HAS DEVELOPED TO THE EAST OF THE BOUNDARY AN IS MOVING INTO NW
PORTIONS OF THE CWFA. PRECIP WILL CONTINUE TO INCREASE FOR MUCH OF
THE AREA TODAY AS THE FRONT SLOWLY PUSHES EASTWARD.
THE NORTHERN END OF THE FRONT WILL MAKE SOME EASTWARD PROGRESS
TODAY...WHILE THE SOUTHERN END WILL LAG UNTIL EARLY SATURDAY
MORNING. A WAVE OF LOW PRESSURE WILL DEVELOP ALONG THE SOUTHERN TAIL
OF THE FRONT TONIGHT...AND FINALLY HELP PUSH THE FRONT THROUGH THE
CWFA ON SATURDAY. THE NORTHERN END OF THE FRONT WILL BECOME
TEMPORARILY STATIONARY NEAR THE TN/GA BORDER THIS EVENING AND
OVERNIGHT. EXPECT SHOWERS AND A FEW THUNDERSTORMS TO TRAIN ACROSS
THE NORTHERN HALF OF THE CWFA...IN THE VICINITY OF THE BOUNDARY
TONIGHT.
MODELS SHOWING A BIT MORE INSTABILITY ACROSS THE SOUTHERN CWFA FOR
THIS AFTERNOON THAN IN PREVIOUS RUNS. STILL...ONLY A COUPLE HUNDRED
JULES OF CAPE. WILL KEEP THUNDER CHANCES AT A MINIMUM TODAY AND ONLY
MENTION A SLIGHT CHANCE. EVEN THOUGH A BREAK IN THE WIDESPREAD
PRECIPITATION IS EXPECTED THIS EVENING...THE CHANCES FOR THUNDER
WILL SLIGHTLY INCREASE AS A MID LEVEL SHORTWAVE TRAVERSES THE AREA
AND STEEPENS LAPSE RATES. STILL...SURFACE INSTABILITY WILL BE
LIMITED...SO WILL CAP THE THUNDER WORDING AT A CHANCE. A BIT MORE
INSTABILITY WILL BE PRESENT SATURDAY AFTERNOON...ESPECIALLY ACROSS
THE SOUTHEAST PORTION OF THE CWFA. THIS AREA HAS THE POTENTIAL FOR
SOME HEATING...WITH TEMPS IN THE LOWER TO MIDDLE 70S. SURFACE BASED
CAPES SHOULD RANGE FROM 500 TO 1000 J/KG. THE BEST SHEAR SHOULD
LAG...ALONG WITH THE FRONTAL BOUNDARY. HOWEVER...WILL NOT RULE OUT
STRONG THUNDERSTORMS WITH ISOLATED SEVERE STORMS POSSIBLE. DAMAGING
WIND GUSTS SHOULD BE THE PRIMARY MODE OF SEVERE WEATHER.
NLISTEMAA
LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
FOR THE MOST PART...SYSTEM THAT BRINGS RAIN TO THE AREA IN THE
SHORT TERM SHOULD HAVE EXITED THE AREA BY THE BEGINNING OF THE
LONG TERM. THE EXCEPTION TO THIS IS ACROSS FAR NORTHEAST GEORGIA
AND THE FAR SOUTHEAST PART OF THE CWA WHERE SOME RAIN COULD LINGER
THROUGH SATURDAY NIGHT. AT THIS POINT...IT APPEARS THE
PRECIPITATION SHOULD END ACROSS THE NE GA MOUNTAINS BEFORE THE
COOLER TEMPERATURES MOVE IN. AFTER THIS HIGH PRESSURE WILL
DOMINATE THROUGH ABOUT MID WEEK. BOTH THE GFS AND THE ECMWF
SUGGEST THE NEXT SYSTEM MOVING THROUGH IN THE LATER HALF OF THE
WEEK. INSTABILITY VALUES SUPPORT THE MENTION OF THUNDER IN THE
FORECAST THURSDAY INTO FRIDAY.
11
HYDROLOGY...
ONE CONCERN FOR THE FORECAST PERIOD IS LOCALLY HEAVY RAINFALL. PWATS
JUST UNDER AN INCH AND HALF WILL BE LIKELY THIS AFTERNOON THROUGH
SATURDAY. THESE NUMBERS ARE VERY CLOSE TO BEING 2SD ABOVE NORMAL FOR
THIS TIME OF YEAR. 6HR FFG GUIDANCE RANGES FROM AROUND 2 TO 3
INCHES ACROSS THE CWFA. STORM TOTAL PRECIP FROM TODAY THROUGH
SATURDAY NIGHT AVERAGES AN INCH AND A HALF TO JUST ABOUT TWO AND
THREE QUARTERS OF AN INCH. SINCE THE RAINFALL IS EXPECTED TO BE OVER
A LONGER PERIOD OF TIME...FF ISN`T A MAJOR CONCERN AT THIS TIME.
HOWEVER...WHERE THUNDERSTORMS REPEATEDLY TRAIN...SOME LOCALIZED FF
IS POSSIBLE. DO EXPECT SOME RISES ON THE RIVERS BUT NOT CONFIDENT
ENOUGH TO SAY IF RIVERS WILL GO INTO FLOOD YET.
NLISTEMAA
&&
.AVIATION...
18Z UPDATE...
RAIN CONTINUES ACROSS THE AREA THIS AFTERNOON...AND TAF SITES ARE
LARGELY IFR. ANTICIPATE THE IFR CIGS TO CONTINUE INTO THE
OVERNIGHT PERIOD. ATL AND AHN AREA TAFS WILL SEE A BREAK IN THE
RAIN UNTIL 05-06Z. MCN AND CSG CAN EXPECT TO SEE RAINFALL INTO THE
EVENING HOURS. RAIN WILL TAPER OFF INTO THE OVERNIGHT PERIOD...AND
START BACK UP AROUND 06-08Z. TS POTENTIAL FOR SATURDAY IS STILL
LOW ENOUGH WHERE IT IS NOT ADVERTISED IN ANY TAFS AT THIS TIME.
THE BEST TIMING WOULD BE FROM 15-20Z SATURDAY IN THE CSG AND MCN
AREAS AND SOUTHWARD. SE WINDS WILL PERSIST THROUGH 10-12Z AS THE
FRONT PUSHES THROUGH THE ATL AREA AND SHIFTS WINDS TO THE NW. CSG
AND MCN WILL SEE THIS SHIFT CLOSER TO 14-16Z. SPEEDS WILL INCREASE
TO 10-15KT WITH GUSTS TO 20-25KT BY LATE SATURDAY MORNING.
//ATL CONFIDENCE...18Z UPDATE...
MEDIUM CONFIDENCE ON ALL ELEMENTS.
31
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 63 54 72 42 / 100 60 70 5
ATLANTA 62 56 69 42 / 100 70 70 5
BLAIRSVILLE 57 52 65 37 / 100 70 80 10
CARTERSVILLE 61 56 69 41 / 100 80 70 5
COLUMBUS 64 60 73 47 / 100 70 60 5
GAINESVILLE 58 53 68 41 / 100 70 80 5
MACON 65 58 74 44 / 100 60 60 5
ROME 62 56 68 42 / 100 80 80 5
PEACHTREE CITY 63 56 71 41 / 100 70 70 5
VIDALIA 69 60 75 48 / 100 80 60 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...31
LONG TERM....BAKER
AVIATION...31
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
200 PM EDT FRI MAR 28 2014
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL PREVAIL AS WEAK UPPER DISTURBANCES
MOVE THROUGH THE AREA TODAY AND TONIGHT. A COLD FRONT WILL CROSS
THE REGION SATURDAY AFTERNOON AND EVENING...FOLLOWED BY DRY HIGH
PRESSURE THROUGH THURSDAY. A COLD FRONT MAY AFFECT THE AREA NEXT
FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLY THIS AFTERNOON...AS EXPECTED CONVECTION HAS REMAINED QUITE
SHALLOW SO FAR AND HAS BEEN ON A BIT OF A DIMINISHING TREND AS IT
PUSHES IN FROM THE WEST. THERE ARE TWO MAIN AREAS OF PRECIPITATION
AT THIS POINT...THE ONE TO THE WEST ASSOCIATED WITH THE UPPER
SHORTWAVE AND UPSTREAM CONVECTION...AND THE ONE TO THE EAST WHICH
IS WHERE THE MORNING SHOWERS FIRST STARTED IN THE SOUTHERLY
MOISTURE FEED. I HAVE MADE SOME TWEAKS TO POPS TO BETTER MATCH
ONGOING CONDITIONS...AS WELL AS TEMPERATURES...BUT THE OVERALL
FORECAST REMAINS ON TRACK.
LATE THIS MORNING...CLOUDS HAVE STEADILY FILLED IN ACROSS THE
FORECAST AREA WITH MUCH OF IT BECOMING OVERCAST NOW. THERE ARE
STILL SOME BREAKS ON VISIBLE SATELLITE IMAGERY...BUT THESE SHOULD
FILL IN THROUGH THE DAY ESPECIALLY AS MID/HIGH CLOUDS STREAM IN
FROM ONGOING CONVECTION TO THE WEST. RADAR IMAGERY SHOWS PERIODIC
SHOWERS MOVING ONSHORE IN THE SOUTHERLY FLOW...MAINLY AFFECTING
CHARLESTON AND BERKELEY COUNTIES THIS MORNING. DIAGNOSING WHAT IS
CURRENTLY GOING ON AROUND THE REGION...THERE IS A FAIRLY LARGE
COMPLEX OF CONVECTION ONGOING ALONG THE GULF COAST FROM AROUND
NEW ORLEANS TO THE WESTERN FLORIDA PANHANDLE. BASED ON REGIONAL
RAOB/S THIS CONVECTION APPEARS TO BE ASSOCIATED WITH AN AREA OF
ELEVATED INSTABILITY. THIS IS FURTHER SUPPORTED BY NEGATIVE
SHOWALTER INDICES FROM THE RAP AND AN AREA OF ENHANCED MID LEVEL
LAPSE RATES NOTED FROM THE SPC MESOANALYSIS PAGE. FOR
INSTANCE...COMPARING THE 12Z KTLH AND KCHS SHOWS SIMILAR MID LEVEL
ENVIRONMENTS OTHER THAN THE PROMINENT SUBSIDENCE INVERSION NOTED
IN THE KCHS SOUNDING AT AROUND 650 MB. THIS INVERSION IS SUPPORTED
BY INTERROGATING ALL TILTS RADAR OF THE CURRENT SHOWER
ACTIVITY...WHICH SHOWS THE DEPTH OF REFLECTIVITY SHUTTING OFF
AROUND 11 KFT...WHICH IS NEAR THE 650 MB LEVEL. SO THE BEST MID
LEVEL ENVIRONMENT IS CERTAINLY TO OUR WEST AND SOUTHWEST AND BASED
ON CURRENT HI-RES MODEL RUNS IT APPEARS THAT WILL CONTINUE THROUGH
THE DAY. THE 11Z HRRR APPEARS TO BE HANDLING THE ONGOING
CONVECTION THE BEST...AND THROUGH THE DAY IT TAKES THE MOST
INTENSE UPSTREAM CONVECTION IN A SOUTHEASTWARD DIRECTION OVER THE
FLORIDA PANHANDLE AND THE EASTERN GULF. THIS SEEMS REASONABLE AS
THE BEST MID LEVEL ENVIRONMENT AND LATER SURFACE BASED INSTABILITY
WILL BE TO THE SOUTH AND SOUTHEAST OF ITS CURRENT LOCATION.
SO...FOR THE FORECAST AREA...THE THINKING IS THAT WE WILL CONTINUE
TO SEE SHALLOW CONVECTION AT BEST. I HAVE ADJUSTED POPS
ACCORDINGLY...AND THE SCHEME FAVORS THE EASTERN AREAS NOW AND THEN
THE WESTERN AREAS LATER AS THE DIMINISHING UPSTREAM
SHOWERS/CONVECTION ATTEMPT TO PUSH IN. WITH THE CLOUD COVER
ONGOING AND EXPECTED...HIGH TEMPERATURES ARE TRICKY. I HAVE
LOWERED VALUES MORE INTO THE LOW TO MID 70S...BUT THIS COULD BE ON
THE LOW END IF WE GET MORE SUN THAN EXPECTED.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
TONIGHT...ATLANTIC HIGH PRESSURE WILL PREVAIL AS A COLD FRONT
APPROACHES FROM THE TENNESSEE VALLEY AND DEEP SOUTH. SOUTHERLY
FLOW WILL CONTINUE TO ADVECT DEEP MOISTURE INTO THE REGION. THE
COMBINATION OF THE DEEP LAYERED MOISTURE...FORCING FOR ASCENT
ASSOCIATED WITH THE RIGHT ENTRANCE REGION OF THE UPPER LEVEL
JET...AND A POTENT SHORT WAVE PASSING ALOFT WILL SUPPORT SCATTERED
TO NUMEROUS SHOWERS ACROSS THE AREA...ESPECIALLY LATE THIS EVENING
AND OVERNIGHT. IN ADDITION...INSTABILITY PARAMETERS/MID LEVEL
LAPSE RATES ARE SUPPORTIVE OF AT LEAST ISOLATED THUNDERSTORMS AS
WELL. TEMPERATURES WILL NOT FALL SIGNIFICANTLY GIVEN THE SOUTHERLY
FLOW AND CLOUD COVER...WITH LOWS EXPECTED TO BE AROUND 60 IN MOST
AREAS.
A POTENT UPPER SHORTWAVE WILL MOVE INTO THE CENTRAL APPALACHIANS
ON SATURDAY. SOUTHWEST FLOW WILL STRENGTHEN CONSIDERABLY AS THE
DAY WEARS ON...WITH 0-6 KM WINDS 40-45 KT BY 00Z SUN. THIS WILL
ALSO INCREASE MOISTURE ACROSS THE AREA WITH PWATS ABOVE 1.50
INCHES BY 18Z SAT. A COLD FRONT IS EXPECTED TO SWEEP THROUGH THE
AREA SATURDAY EVENING. THERE REMAINS CONSIDERABLE UNCERTAINTY
REGARDING THE DEGREE OF BOUNDARY LAYER DESTABILIZATION AHEAD OF
THE FRONT. GIVEN THE EXTENSIVE LOW-LEVEL MOISTURE ADVECTING INTO
THE REGION DURING THE DAY WE WOULD EXPECT TO HAVE QUITE A BIT OF
LOW STRATOCUMULUS IN PLACE. HOWEVER SOME OF THE GUIDANCE IS
DEPICTING A WEAK DRY SLOT DURING THE MIDDAY HOURS AFTER A BATCH OF
MORNING PRECIP MOVES THROUGH. BOTH THE GFS AND NAM ARE SHOWING
1500 J/KG CAPES WITH LIFTED INDICES BELOW -4C DURING THE AFTERNOON
ACROSS SOUTHEAST GA. THIS COINCIDES WITH 40-45 KT OF BULK SHEAR.
IT IS ALSO WORTH NOTING THAT THE STORM PREDICTION CENTER STILL
SHOWS OUR ENTIRE FORECAST AREA WITHIN THE DAY 2 SLIGHT RISK. WE
PLAN TO ADD MENTION OF POSSIBLE SEVERE WEATHER TO THE HAZARDOUS
WEATHER OUTLOOK.
STRONG LOW-LEVEL WARM ADVECTION AND PRE-FRONTAL COMPRESSION ON
SATURDAY WILL PUSH HIGH TEMPS INTO THE UPPER 70S. THIS COULD
POTENTIALLY BE TOO COOL IF SOME BREAKS DEVELOP IN THE CLOUDS.
CONSIDERABLE COVERAGE OF SHOWERS AND THUNDERSTORMS IS EXPECTED
THROUGH SATURDAY EVENING BEFORE PRECIP TAPERS OFF BEHIND THE FRONT.
A SLIGHT COOL DOWN IS EXPECTED FOR SUNDAY DUE TO COLD ADVECTION WITH
THE HIGH BUILDING IN...HOWEVER DOWNSLOPE FLOW WILL ALLOW TEMPS TO
REACH 70 OR THEREABOUTS. A 30-35 KT GEOSTROPHIC WIND FIELD AND DEEP
MIXING WILL RESULT IN BREEZY CONDITIONS ESPECIALLY DURING THE HOURS
OF PEAK HEATING.
DRY WEATHER WITH MODERATING TEMPERATURES EXPECTED ON MONDAY WITH
HIGHS REBOUNDING INTO THE LOWER TO MIDDLE 70S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A BROAD UPPER LEVEL RIDGE WILL PREVAIL MONDAY NIGHT THROUGH THURSDAY
WITH DRY HIGH PRESSURE AT THE SURFACE. THIS WILL RESULT IN ABOVE
NORMAL TEMPERATURES WITH HIGHS CLIMBING INTO THE UPPER 70S OR LOWER
80S AND LOWS MAINLY IN THE 50S. THE UPPER RIDGE BREAKS DOWN ON
FRIDAY WITH A WEAK COLD FRONT POSSIBLY MOVING IN FROM THE WEST.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
EXPECT UNSETTLED CONDITIONS THROUGH 18Z SATURDAY. SCATTERED TO
NUMEROUS SHOWERS HAVE DEVELOPED NEAR THE TERMINALS THIS AFTERNOON
SO A VCSH HAS BEEN ADDED. ALSO...TO ACCOUNT FOR DIRECT
IMPACTS...MVFR CONDITIONS HAVE BEEN ADDED IN A TEMPO GROUP THAT
RUNS THROUGH LATE AFTERNOON MAINLY FOR CEILINGS BUT ALSO FOR
VISIBILITIES AS RAINFALL BRIEFLY BECOMES MODERATE. THERE IS A LOW
CHANCE FOR A RUMBLE OF THUNDER...BUT THE PROBABILITY IS TOO LOW TO
INCLUDE IN THE FORECAST. THIS EVENING AND THROUGH THE OVERNIGHT...IT
IS BECOMING INCREASINGLY LIKELY THAT WIDESPREAD MVFR CEILINGS WILL
DEVELOP. I HAVE TIMED THIS INTO KSAV AT 00Z AND INTO KCHS AT 03Z.
WE WILL LIKELY SEE ADDITIONAL PERIODS OF SHOWERS AT BOTH SITES
LATE THIS EVENING BEFORE THIS AREA OF PRECIPITATION PUSHES OFF TO
THE EAST LATE. GUIDANCE CONTINUES TO INDICATE A LOW TO MODERATE
CHANCE OF IFR CONDITIONS LATE TONIGHT. PROBABILITIES ARE HIGHEST
AT KSAV...BUT I/M NOT READY TO COMMIT TO PREVAILING IFR THIS FAR
OUT. I HAVE TRENDED KSAV DOWN INTO THE LOW END MVFR RANGE STARTING
AT 06Z AND CONTINUING THROUGH THE MID MORNING. CEILINGS SHOULD
LIFT TO LOW END VFR MID/LATE SATURDAY MORNING. A COLD FRONT AND AN
INCREASING POTENTIAL FOR THUNDERSTORMS ALONG IT WILL APPROACH
SATURDAY AFTERNOON. SHOWERS OUT AHEAD OF THE FRONT WILL DEVELOP
FIRST AT KSAV AND WINDS WILL BEGIN TO PICK UP AND BE GUSTY OUT OF
THE SOUTH. THIS WILL ALSO HAPPEN AT KCHS...THOUGH LATER...AND HAS
NOT BEEN INCLUDED AT THIS TIME.
EXTENDED AVIATION OUTLOOK...OCCASIONAL FLIGHT RESTRICTIONS POSSIBLE
SATURDAY AFTERNOON AND EVENING IN SCATTERED SHOWERS AND
THUNDERSTORMS. VFR CONDITIONS EXPECTED THEREAFTER. BREEZY CONDITIONS
EXPECTED ON SUNDAY.
&&
.MARINE...
TODAY...A SOUTHERLY RETURN FLOW WILL BECOME WELL ESTABLISHED
ACROSS THE COASTAL WATERS TODAY AS ATLANTIC HIGH PRESSURE
PREVAILS. DESPITE SOME STRONGER WINDS ALOFT...MIXING WILL REMAIN
LIMITED OVER THE COOLER NEAR SHORE WATERS THUS WINDS AT THE
SURFACE SHOULD NOT EXCEED 10 TO 15 KT. HOWEVER...WINDS OVER THE
OUTER GA WATERS AND IN CHARLESTON HARBOR ALONG THE LAND/SEA
INTERFACE COULD REACH UPWARDS OF 15 TO 20 KT AT TIMES THIS
AFTERNOON. A SOUTHEAST SWELL WILL KEEP SEAS ELEVATED IN THE 3-5 FT
RANGE TODAY...WITH A SMALL POTENTIAL FOR SOME 6 FT SEAS TO
ENCROACH UPON THE FAR REACHES OF THE OUTER GA WATERS. GIVEN
LIMITED CONFIDENCE...HAVE OPTED TO NOT ISSUE A SMALL CRAFT
ADVISORY...ALTHOUGH CONDITIONS COULD WARRANT OTHERWISE LATER
TODAY. DEW POINTS SURGING INTO THE LOWER 60S WITHIN THE SOUTHERLY
FLOW COULD SUPPORT THE DEVELOPMENT OF PATCHY SEA FOG LATER THIS
AFTERNOON ACROSS THE NEAR SHORE WATERS.
TONIGHT...THE SOUTHERLY FLOW WILL STRENGTHEN TO UPWARDS OF 15 TO
20 KT ACROSS THE COASTAL WATERS AS THE SURFACE PRESSURE GRADIENT
TIGHTENS BETWEEN ATLANTIC HIGH PRESSURE AND A COLD FRONT WELL TO
THE WEST. A SOUTHEAST SWELL WILL KEEP SEAS SOLIDLY IN THE 3-5 FT
RANGE...HIGHEST ACROSS THE OUTER GA WATERS. THERE IS A SMALL
POTENTIAL THAT MARGINAL SMALL CRAFT ADVISORY CONDITIONS FOR WINDS
AND/OR SEAS COULD OCCUR OVER THE OUTER GA WATERS...BUT NOT ENOUGH
CONFIDENCE TO RAISE AN ADVISORY AT THIS TIME. THE POTENTIAL FOR
PATCHY SEA FOG WILL PERSIST TONIGHT ACROSS THE NEAR SHORE WATERS
AND CHARLESTON HARBOR AS A WARM/MOIST SOUTHERLY FLOW PREVAILS.
SATURDAY THROUGH TUESDAY...WIND FIELDS WILL INCREASE SATURDAY INTO SATURDAY
NIGHT AS A STRONG COLD FRONT MOVES THROUGH. ON SATURDAY THE FLOW
WILL BE OUT OF THE SOUTH AND CONDITIONS SHOULD REMAIN BELOW
ADVISORY CRITERIA. BUT ONCE COLD ADVECTION CRANKS UP LATE SATURDAY
EVENING AND OVERNIGHT AND GEOSTROPHIC WINDS INCREASE TO 35-40
KT...WE EXPECT SMALL CRAFT ADVISORY CONDITIONS ON MOST IF NOT ALL
MARINE ZONES. CONDITIONS WILL QUICKLY IMPROVE ON SUNDAY AS THE
HIGH PRESSURE CENTER MOVES CLOSER TO THE WATERS. FAIRLY QUIET
WINDS/SEAS ANTICIPATED SUNDAY NIGHT THROUGH MID WEEK AS THE HIGH
PRESSURE DOMINATES.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...BSH
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...BSH
MARINE...JAQ/JRL
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1041 AM EDT FRI MAR 28 2014
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL PREVAIL AS WEAK UPPER DISTURBANCES
MOVE THROUGH THE AREA TODAY AND TONIGHT. A COLD FRONT WILL CROSS
THE REGION SATURDAY AFTERNOON AND EVENING...FOLLOWED BY DRY HIGH
PRESSURE THROUGH THURSDAY. A COLD FRONT MAY AFFECT THE AREA NEXT
FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATE THIS MORNING...CLOUDS HAVE STEADILY FILLED IN ACROSS THE
FORECAST AREA WITH MUCH OF IT BECOMING OVERCAST NOW. THERE ARE
STILL SOME BREAKS ON VISIBLE SATELLITE IMAGERY...BUT THESE SHOULD
FILL IN THROUGH THE DAY ESPECIALLY AS MID/HIGH CLOUDS STREAM IN
FROM ONGOING CONVECTION TO THE WEST. RADAR IMAGERY SHOWS PERIODIC
SHOWERS MOVING ONSHORE IN THE SOUTHERLY FLOW...MAINLY AFFECTING
CHARLESTON AND BERKELEY COUNTIES THIS MORNING. DIAGNOSING WHAT IS
CURRENTLY GOING ON AROUND THE REGION...THERE IS A FAIRLY LARGE
COMPLEX OF CONVECTION ONGOING ALONG THE GULF COAST FROM AROUND
NEW ORLEANS TO THE WESTERN FLORIDA PANHANDLE. BASED ON REGIONAL
RAOB/S THIS CONVECTION APPEARS TO BE ASSOCIATED WITH AN AREA OF
ELEVATED INSTABILITY. THIS IS FURTHER SUPPORTED BY NEGATIVE
SHOWALTER INDICES FROM THE RAP AND AN AREA OF ENHANCED MID LEVEL
LAPSE RATES NOTED FROM THE SPC MESOANALYSIS PAGE. FOR
INSTANCE...COMPARING THE 12Z KTLH AND KCHS SHOWS SIMILAR MID LEVEL
ENVIRONMENTS OTHER THAN THE PROMINENT SUBSIDENCE INVERSION NOTED
IN THE KCHS SOUNDING AT AROUND 650 MB. THIS INVERSION IS SUPPORTED
BY INTERROGATING ALL TILTS RADAR OF THE CURRENT SHOWER
ACTIVITY...WHICH SHOWS THE DEPTH OF REFLECTIVITY SHUTTING OFF
AROUND 11 KFT...WHICH IS NEAR THE 650 MB LEVEL. SO THE BEST MID
LEVEL ENVIRONMENT IS CERTAINLY TO OUR WEST AND SOUTHWEST AND BASED
ON CURRENT HI-RES MODEL RUNS IT APPEARS THAT WILL CONTINUE THROUGH
THE DAY. THE 11Z HRRR APPEARS TO BE HANDLING THE ONGOING
CONVECTION THE BEST...AND THROUGH THE DAY IT TAKES THE MOST
INTENSE UPSTREAM CONVECTION IN A SOUTHEASTWARD DIRECTION OVER THE
FLORIDA PANHANDLE AND THE EASTERN GULF. THIS SEEMS REASONABLE AS
THE BEST MID LEVEL ENVIRONMENT AND LATER SURFACE BASED INSTABILITY
WILL BE TO THE SOUTH AND SOUTHEAST OF ITS CURRENT LOCATION.
SO...FOR THE FORECAST AREA...THE THINKING IS THAT WE WILL CONTINUE
TO SEE SHALLOW CONVECTION AT BEST. I HAVE ADJUSTED POPS
ACCORDINGLY...AND THE SCHEME FAVORS THE EASTERN AREAS NOW AND THEN
THE WESTERN AREAS LATER AS THE DIMINISHING UPSTREAM
SHOWERS/CONVECTION ATTEMPT TO PUSH IN. WITH THE CLOUD COVER
ONGOING AND EXPECTED...HIGH TEMPERATURES ARE TRICKY. I HAVE
LOWERED VALUES MORE INTO THE LOW TO MID 70S...BUT THIS COULD BE ON
THE LOW END IF WE GET MORE SUN THAN EXPECTED.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
TONIGHT...ATLANTIC HIGH PRESSURE WILL PREVAIL AS A COLD FRONT
APPROACHES FROM THE TENNESSEE VALLEY AND DEEP SOUTH. SOUTHERLY
FLOW WILL CONTINUE TO ADVECT DEEP MOISTURE INTO THE REGION. THE
COMBINATION OF THE DEEP LAYERED MOISTURE...FORCING FOR ASCENT
ASSOCIATED WITH THE RIGHT ENTRANCE REGION OF THE UPPER LEVEL
JET...AND A POTENT SHORT WAVE PASSING ALOFT WILL SUPPORT SCATTERED
TO NUMEROUS SHOWERS ACROSS THE AREA...ESPECIALLY LATE THIS EVENING
AND OVERNIGHT. IN ADDITION...INSTABILITY PARAMETERS/MID LEVEL
LAPSE RATES ARE SUPPORTIVE OF AT LEAST ISOLATED THUNDERSTORMS AS
WELL. TEMPERATURES WILL NOT FALL SIGNIFICANTLY GIVEN THE SOUTHERLY
FLOW AND CLOUD COVER...WITH LOWS EXPECTED TO BE AROUND 60 IN MOST
AREAS.
A POTENT UPPER SHORTWAVE WILL MOVE INTO THE CENTRAL APPALACHIANS
ON SATURDAY. SOUTHWEST FLOW WILL STRENGTHEN CONSIDERABLY AS THE
DAY WEARS ON...WITH 0-6 KM WINDS 40-45 KT BY 00Z SUN. THIS WILL
ALSO INCREASE MOISTURE ACROSS THE AREA WITH PWATS ABOVE 1.50
INCHES BY 18Z SAT. A COLD FRONT IS EXPECTED TO SWEEP THROUGH THE
AREA SATURDAY EVENING. THERE REMAINS CONSIDERABLE UNCERTAINTY
REGARDING THE DEGREE OF BOUNDARY LAYER DESTABILIZATION AHEAD OF
THE FRONT. GIVEN THE EXTENSIVE LOW-LEVEL MOISTURE ADVECTING INTO
THE REGION DURING THE DAY WE WOULD EXPECT TO HAVE QUITE A BIT OF
LOW STRATOCUMULUS IN PLACE. HOWEVER SOME OF THE GUIDANCE IS
DEPICTING A WEAK DRY SLOT DURING THE MIDDAY HOURS AFTER A BATCH OF
MORNING PRECIP MOVES THROUGH. BOTH THE GFS AND NAM ARE SHOWING
1500 J/KG CAPES WITH LIFTED INDICES BELOW -4C DURING THE AFTERNOON
ACROSS SOUTHEAST GA. THIS COINCIDES WITH 40-45 KT OF BULK SHEAR.
IT IS ALSO WORTH NOTING THAT THE STORM PREDICTION CENTER STILL
SHOWS OUR ENTIRE FORECAST AREA WITHIN THE DAY 2 SLIGHT RISK. WE
PLAN TO ADD MENTION OF POSSIBLE SEVERE WEATHER TO THE HAZARDOUS
WEATHER OUTLOOK.
STRONG LOW-LEVEL WARM ADVECTION AND PRE-FRONTAL COMPRESSION ON
SATURDAY WILL PUSH HIGH TEMPS INTO THE UPPER 70S. THIS COULD
POTENTIALLY BE TOO COOL IF SOME BREAKS DEVELOP IN THE CLOUDS.
CONSIDERABLE COVERAGE OF SHOWERS AND THUNDERSTORMS IS EXPECTED
THROUGH SATURDAY EVENING BEFORE PRECIP TAPERS OFF BEHIND THE FRONT.
A SLIGHT COOL DOWN IS EXPECTED FOR SUNDAY DUE TO COLD ADVECTION WITH
THE HIGH BUILDING IN...HOWEVER DOWNSLOPE FLOW WILL ALLOW TEMPS TO
REACH 70 OR THEREABOUTS. A 30-35 KT GEOSTROPHIC WIND FIELD AND DEEP
MIXING WILL RESULT IN BREEZY CONDITIONS ESPECIALLY DURING THE HOURS
OF PEAK HEATING.
DRY WEATHER WITH MODERATING TEMPERATURES EXPECTED ON MONDAY WITH
HIGHS REBOUNDING INTO THE LOWER TO MIDDLE 70S.
&&
.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
A BROAD UPPER LEVEL RIDGE WILL PREVAIL MONDAY NIGHT THROUGH THURSDAY
WITH DRY HIGH PRESSURE AT THE SURFACE. THIS WILL RESULT IN ABOVE
NORMAL TEMPERATURES WITH HIGHS CLIMBING INTO THE UPPER 70S OR LOWER
80S AND LOWS MAINLY IN THE 50S. THE UPPER RIDGE BREAKS DOWN ON
FRIDAY WITH A WEAK COLD FRONT POSSIBLY MOVING IN FROM THE WEST.
&&
.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS SHOULD GENERALLY PREVAIL AT BOTH KCHS AND KSAV
THROUGH AT LEAST THIS AFTERNOON. BRIEF/ISOLATED SHOWERS ARE
POSSIBLE AROUND KCHS THROUGH MUCH OF THE MORNING...BUT GIVEN
LIMITED COVERAGE AND OVERALL LOW CONFIDENCE...THERE WILL BE NO
MENTION IN THE KCHS TAF. BREEZY CONDITIONS WILL DEVELOP THIS
AFTERNOON WITH GUSTS UPWARDS OF 20 KT AT TIMES. INCREASING LOW
LEVEL MOISTURE AND A PASSING UPPER LEVEL DISTURBANCE WILL RESULT
IN SCATTERED TO NUMEROUS SHOWERS AND PERHAPS A FEW THUNDERSTORMS
LATER THIS AFTERNOON INTO TONIGHT. AS A RESULT...HAVE ADDED VICINITY
SHOWERS TO THE TAF/S BEGINNING EARLY THIS AFTERNOON...THEN
PREVAILING SHOWERS LATE THIS AFTERNOON THROUGH THIS EVENING.
CEILINGS COULD PERIODICALLY LOWER TO MVFR LEVELS LATE THIS AFTERNOON AND
THIS EVENING...ESPECIALLY IN SHOWERS. THEN...MVFR CEILINGS WILL
BECOME MORE PREVALENT AFTER MIDNIGHT AT BOTH TERMINALS...WITH EVEN
A LOW PROBABILITY OF IFR CEILINGS DEVELOPING AT KSAV.
EXTENDED AVIATION OUTLOOK...OCCASIONAL FLIGHT RESTRICTIONS POSSIBLE
SATURDAY AFTERNOON AND EVENING IN SCATTERED SHOWERS AND
THUNDERSTORMS. VFR CONDITIONS EXPECTED THEREAFTER. BREEZY CONDITIONS
EXPECTED ON SUNDAY.
&&
.MARINE...
TODAY...A SOUTHERLY RETURN FLOW WILL BECOME WELL ESTABLISHED
ACROSS THE COASTAL WATERS TODAY AS ATLANTIC HIGH PRESSURE
PREVAILS. DESPITE SOME STRONGER WINDS ALOFT...MIXING WILL REMAIN
LIMITED OVER THE COOLER NEAR SHORE WATERS THUS WINDS AT THE
SURFACE SHOULD NOT EXCEED 10 TO 15 KT. HOWEVER...WINDS OVER THE
OUTER GA WATERS AND IN CHARLESTON HARBOR ALONG THE LAND/SEA
INTERFACE COULD REACH UPWARDS OF 15 TO 20 KT AT TIMES THIS
AFTERNOON. A SOUTHEAST SWELL WILL KEEP SEAS ELEVATED IN THE 3-5 FT
RANGE TODAY...WITH A SMALL POTENTIAL FOR SOME 6 FT SEAS TO
ENCROACH UPON THE FAR REACHES OF THE OUTER GA WATERS. GIVEN
LIMITED CONFIDENCE...HAVE OPTED TO NOT ISSUE A SMALL CRAFT
ADVISORY...ALTHOUGH CONDITIONS COULD WARRANT OTHERWISE LATER
TODAY. DEW POINTS SURGING INTO THE LOWER 60S WITHIN THE SOUTHERLY
FLOW COULD SUPPORT THE DEVELOPMENT OF PATCHY SEA FOG LATER THIS
AFTERNOON ACROSS THE NEAR SHORE WATERS.
TONIGHT...THE SOUTHERLY FLOW WILL STRENGTHEN TO UPWARDS OF 15 TO
20 KT ACROSS THE COASTAL WATERS AS THE SURFACE PRESSURE GRADIENT
TIGHTENS BETWEEN ATLANTIC HIGH PRESSURE AND A COLD FRONT WELL TO
THE WEST. A SOUTHEAST SWELL WILL KEEP SEAS SOLIDLY IN THE 3-5 FT
RANGE...HIGHEST ACROSS THE OUTER GA WATERS. THERE IS A SMALL
POTENTIAL THAT MARGINAL SMALL CRAFT ADVISORY CONDITIONS FOR WINDS
AND/OR SEAS COULD OCCUR OVER THE OUTER GA WATERS...BUT NOT ENOUGH
CONFIDENCE TO RAISE AN ADVISORY AT THIS TIME. THE POTENTIAL FOR
PATCHY SEA FOG WILL PERSIST TONIGHT ACROSS THE NEAR SHORE WATERS
AND CHARLESTON HARBOR AS A WARM/MOIST SOUTHERLY FLOW PREVAILS.
SATURDAY THROUGH TUESDAY...WIND FIELDS WILL INCREASE SATURDAY INTO SATURDAY
NIGHT AS A STRONG COLD FRONT MOVES THROUGH. ON SATURDAY THE FLOW
WILL BE OUT OF THE SOUTH AND CONDITIONS SHOULD REMAIN BELOW
ADVISORY CRITERIA. BUT ONCE COLD ADVECTION CRANKS UP LATE SATURDAY
EVENING AND OVERNIGHT AND GEOSTROPHIC WINDS INCREASE TO 35-40
KT...WE EXPECT SMALL CRAFT ADVISORY CONDITIONS ON MOST IF NOT ALL
MARINE ZONES. CONDITIONS WILL QUICKLY IMPROVE ON SUNDAY AS THE
HIGH PRESSURE CENTER MOVES CLOSER TO THE WATERS. FAIRLY QUIET
WINDS/SEAS ANTICIPATED SUNDAY NIGHT THROUGH MID WEEK AS THE HIGH
PRESSURE DOMINATES.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...BSH
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...JAQ/JRL
MARINE...JAQ/JRL
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
1040 AM EDT FRI MAR 28 2014
.UPDATE...
HAVE MADE SIGNIFICANT ADJUSTMENTS TO THE FORECAST TO ACCOUNT FOR
LATEST THINKING WITH TODAYS WEATHER. AXIS OF PRECIPITATION IS
FURTHER SOUTH THAN ORIGINALLY ANTICIPATED...AND PREVIOUS FORECAST
POP AND WX GRIDS DID NOT MATCH THIS POSITIONING.
OVERALL...MODEL GUIDANCE WITH THIS SYSTEM IS POOR...WITH VERY FEW
DEPICTING THE CURRENT RADAR TRENDS WELL. HAVE OVERALL GONE WITH
THE HRRR WHICH SEEMS TO HAVE A BETTER HANDLE ON THE CURRENT
CONDITIONS. THE HRRR DOES SUGGEST MUCH OF THE COMPLEX IN MS/AL
WILL ORGANIZE INTO THIS AFTERNOON...BECOMING MORE LINEAR IN
NATURE...AND PUSHING ACROSS SOUTHWEST GEORGIA. ALTHOUGH THERE IS A
QUESTION OF WHETHER THIS LINEAR CONVECTION WILL MATERIALIZE...THE
HRRR CONTINUES TO SHOW MUCH OF NORTH GEORGIA CUT OFF FROM GULF
MOISTURE...AND LIMITS THE AMOUNT OF PRECIP OVER THE NORTHERN
SECTIONS OF THE CWA. AS A RESULT...HAVE CONTINUED THE TREND OF
HIGHEST POPS ACROSS CENTRAL GEORGIA INTO THE OVERNIGHT PERIOD.
WILL CONTINUE TO UPDATE THE GRIDS AS NECESSARY...ESPECIALLY THE
NEXT 24 HOURS.
31
.PREV DISCUSSION... /ISSUED 717 AM EDT FRI MAR 28 2014/
PREV DISCUSSION... /ISSUED 341 AM EDT FRI MAR 28 2014/
SHORT TERM /TODAY THROUGH SATURDAY/...
SURFACE ANALYSIS SHOWS A COLD FRONT STRETCHING FROM THE CENTRAL
GREAT LAKES BACK THROUGH THE ARKLATEX. A LARGE AREA OF PRECIPITATION
HAS DEVELOPED TO THE EAST OF THE BOUNDARY AN IS MOVING INTO NW
PORTIONS OF THE CWFA. PRECIP WILL CONTINUE TO INCREASE FOR MUCH OF
THE AREA TODAY AS THE FRONT SLOWLY PUSHES EASTWARD.
THE NORTHERN END OF THE FRONT WILL MAKE SOME EASTWARD PROGRESS
TODAY...WHILE THE SOUTHERN END WILL LAG UNTIL EARLY SATURDAY
MORNING. A WAVE OF LOW PRESSURE WILL DEVELOP ALONG THE SOUTHERN TAIL
OF THE FRONT TONIGHT...AND FINALLY HELP PUSH THE FRONT THROUGH THE
CWFA ON SATURDAY. THE NORTHERN END OF THE FRONT WILL BECOME
TEMPORARILY STATIONARY NEAR THE TN/GA BORDER THIS EVENING AND
OVERNIGHT. EXPECT SHOWERS AND A FEW THUNDERSTORMS TO TRAIN ACROSS
THE NORTHERN HALF OF THE CWFA...IN THE VICINITY OF THE BOUNDARY
TONIGHT.
MODELS SHOWING A BIT MORE INSTABILITY ACROSS THE SOUTHERN CWFA FOR
THIS AFTERNOON THAN IN PREVIOUS RUNS. STILL...ONLY A COUPLE HUNDRED
JULES OF CAPE. WILL KEEP THUNDER CHANCES AT A MINIMUM TODAY AND ONLY
MENTION A SLIGHT CHANCE. EVEN THOUGH A BREAK IN THE WIDESPREAD
PRECIPITATION IS EXPECTED THIS EVENING...THE CHANCES FOR THUNDER
WILL SLIGHTLY INCREASE AS A MID LEVEL SHORTWAVE TRAVERSES THE AREA
AND STEEPENS LAPSE RATES. STILL...SURFACE INSTABILITY WILL BE
LIMITED...SO WILL CAP THE THUNDER WORDING AT A CHANCE. A BIT MORE
INSTABILITY WILL BE PRESENT SATURDAY AFTERNOON...ESPECIALLY ACROSS
THE SOUTHEAST PORTION OF THE CWFA. THIS AREA HAS THE POTENTIAL FOR
SOME HEATING...WITH TEMPS IN THE LOWER TO MIDDLE 70S. SURFACE BASED
CAPES SHOULD RANGE FROM 500 TO 1000 J/KG. THE BEST SHEAR SHOULD
LAG...ALONG WITH THE FRONTAL BOUNDARY. HOWEVER...WILL NOT RULE OUT
STRONG THUNDERSTORMS WITH ISOLATED SEVERE STORMS POSSIBLE. DAMAGING
WIND GUSTS SHOULD BE THE PRIMARY MODE OF SEVERE WEATHER.
NLISTEMAA
LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
FOR THE MOST PART...SYSTEM THAT BRINGS RAIN TO THE AREA IN THE
SHORT TERM SHOULD HAVE EXITED THE AREA BY THE BEGINNING OF THE
LONG TERM. THE EXCEPTION TO THIS IS ACROSS FAR NORTHEAST GEORGIA
AND THE FAR SOUTHEAST PART OF THE CWA WHERE SOME RAIN COULD LINGER
THROUGH SATURDAY NIGHT. AT THIS POINT...IT APPEARS THE
PRECIPITATION SHOULD END ACROSS THE NE GA MOUNTAINS BEFORE THE
COOLER TEMPERATURES MOVE IN. AFTER THIS HIGH PRESSURE WILL
DOMINATE THROUGH ABOUT MID WEEK. BOTH THE GFS AND THE ECMWF
SUGGEST THE NEXT SYSTEM MOVING THROUGH IN THE LATER HALF OF THE
WEEK. INSTABILITY VALUES SUPPORT THE MENTION OF THUNDER IN THE
FORECAST THURSDAY INTO FRIDAY.
11
HYDROLOGY...
ONE CONCERN FOR THE FORECAST PERIOD IS LOCALLY HEAVY RAINFALL. PWATS
JUST UNDER AN INCH AND HALF WILL BE LIKELY THIS AFTERNOON THROUGH
SATURDAY. THESE NUMBERS ARE VERY CLOSE TO BEING 2SD ABOVE NORMAL FOR
THIS TIME OF YEAR. 6HR FFG GUIDANCE RANGES FROM AROUND 2 TO 3
INCHES ACROSS THE CWFA. STORM TOTAL PRECIP FROM TODAY THROUGH
SATURDAY NIGHT AVERAGES AN INCH AND A HALF TO JUST ABOUT TWO AND
THREE QUARTERS OF AN INCH. SINCE THE RAINFALL IS EXPECTED TO BE OVER
A LONGER PERIOD OF TIME...FF ISN`T A MAJOR CONCERN AT THIS TIME.
HOWEVER...WHERE THUNDERSTORMS REPEATEDLY TRAIN...SOME LOCALIZED FF
IS POSSIBLE. DO EXPECT SOME RISES ON THE RIVERS BUT NOT CONFIDENT
ENOUGH TO SAY IF RIVERS WILL GO INTO FLOOD YET.
NLISTEMAA
AVIATION...
12Z UPDATE...
RAIN HAS STARTED TO OVERSPREAD THE METRO AREA THIS MORNING AHEAD
OF A COLD FRONT ACROSS THE ARKLATEX. A BREAK IN THE PRECIP IS
EXPECTED THIS EVENING...BUT PRECIP WILL FILL IN AGAIN EARLY FRIDAY
AS THE COLD FRONT MOVES THROUGH. MODELS ARE PROGGING IFR CIGS WITH
THE WIDESPREAD RAIN TODAY...AND THINK THAT IS REASONABLE. CIGS MAY
END UP LOWER THAN FORECAST OVERNIGHT...BUT FOR NOW WILL KEEP LOWEST VALUES
AROUND 500FT. WINDS WILL REMAIN OUT OF THE SE.
//ATL CONFIDENCE...12Z UPDATE...
MEDIUM CONFIDENCE ON IFR CIGS. HIGH CONFIDENCE REMAINING
ELEMENTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 64 55 69 40 / 100 80 70 10
ATLANTA 63 57 66 41 / 100 70 70 5
BLAIRSVILLE 56 52 60 35 / 100 80 60 20
CARTERSVILLE 62 57 65 40 / 100 80 70 5
COLUMBUS 67 60 72 45 / 100 50 60 5
GAINESVILLE 59 54 64 39 / 100 80 70 5
MACON 69 59 73 42 / 90 50 60 10
ROME 62 57 64 40 / 100 80 70 5
PEACHTREE CITY 64 57 68 38 / 100 70 70 5
VIDALIA 76 61 75 47 / 60 40 70 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...31
LONG TERM....BAKER
AVIATION...31
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
756 AM EDT FRI MAR 28 2014
.SYNOPSIS...
MOISTURE WILL BE HIGH AHEAD OF A SLOW MOVING FRONTAL SYSTEM. THE
FRONT WILL MOVE THROUGH THE FORECAST AREA LATE SATURDAY. HIGH
PRESSURE AND DRIER CONDITIONS WILL PREVAIL SUNDAY AND MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
TODAY...A MOIST SOUTHERLY FLOW AND ISENTROPIC LIFT SHOULD HELP SUPPORT
SHOWERS TODAY. THE NAM AND GFS MOS PLUS RADAR TRENDS SUPPORT HIGH
POPS. BASED TIMING ON RADAR TRENDS AND THE LATEST HRRR. CLOUDINESS
AND SHOWERS SHOULD LIMIT INSTABILITY. THE NAM INDICATES JUST WEAK
INSTABILITY. THE HRRR AND SATELLITE TRENDS SUPPORT KEEPING THE
STRONGER CONVECTION SOUTH OF THE FORECAST AREA. EXPECT MAINLY
SHOWERS INSTEAD OF THUNDERSTORMS. USED THE COOLER TEMPERATURE
GUIDANCE BECAUSE OF CLOUDINESS.
TONIGHT...THE MOIST SOUTHERLY FLOW AND ISENTROPIC LIFT SUPPORT
CONTINUED HIGH POPS TONIGHT. COVERAGE MAY INCREASE TOWARD MORNING
AHEAD OF A MID-LEVEL SHORTWAVE TROUGH. COOLING ALOFT ASSOCIATED
WITH THE UPPER TROUGH SUPPORTS A HIGHER CHANCE OF THUNDERSTORMS
TOWARD MORNING. SHEAR WILL BE ON THE INCREASE INDICATING WELL-
ORGANIZED THUNDERSTORMS MAY OCCUR BUT THE NAM SUGGESTS ANY
SURFACE-BASED INSTABILITY WILL REMAIN WEAK THROUGH THE NIGHT. THE
DIURNAL TIMING SHOULD ALSO HELP LIMIT INSTABILITY. THEREFORE...THE
RISK OF SEVERE THUNDERSTORMS APPEARS LOW AT THIS TIME. THE WARMER
TEMPERATURE GUIDANCE APPEARS BETTER BECAUSE OF CLOUDINESS.
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
SATURDAY...MOISTURE SHOULD BE HIGH AHEAD OF THE COLD FRONT
SATURDAY. THE NAM INDICATES THE DEEPEST MOISTURE EARLY SATURDAY.
THE GFS AND ECMWF SHOW THE DEEPEST MOISTURE AROUND THE MIDDLE OF
THE DAY AHEAD OF THE COLD FRONT. THE MODELS WERE MORE CONSISTENT
WITH COLD FRONTAL PASSAGE LATE IN THE DAY OR EVENING. WE
MAINTAINED LIKELY POPS DURING MUCH OF THE DAY WITH THE TIMING
DIFFICULT BECAUSE ISENTROPIC LIFT APPEARS GREATER IN THE
MORNING...BUT CONVERGENCE AHEAD OF THE COLD FRONT SHOULD BE HIGHER
DURING THE AFTERNOON. SHEAR WILL BE HIGH. THE MODELS INDICATE H85
WINDS OF 35 TO 40 KNOTS. THE NAM INDICATES SURFACE-BASED LI/S NEAR
-3 DURING THE AFTERNOON. THERE WILL BE A THREAT OF SEVERE
THUNDERSTORMS BECAUSE OF THIS SHEAR AND INSTABILITY. ANY LINGERING SHOWERS
AND THUNDERSTORMS SHOULD END FROM WEST TO EAST SATURDAY EVENING
AS DRYING BECOMES DOMINATE BEHIND THE COLD FRONT. WE USED THE
GUIDANCE CONSENSUS FOR THE TEMPERATURE FORECAST.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
THE GFS AND ECMWF INDICATE DRY HIGH PRESSURE SHOULD DOMINATE
DURING MUCH OF THE PERIOD. MOISTURE SHOULD BE ON THE INCREASE LATE
IN THE PERIOD AHEAD OF A COLD FRONT. THE COOLEST NIGHT SHOULD BE
SUNDAY NIGHT. STRONG NOCTURNAL COOLING SHOULD OCCUR WITH DRY HIGH
PRESSURE OVERHEAD AND LIGHT WINDS. AN AVERAGE OF THE GFS...ECMWF
AND EKD MOS SUPPORTS LOWS MAINLY IN THE UPPER 30S. FROST WILL BE
POSSIBLE MAINLY IN THE NORMALLY COLDER LOCATIONS. WARMER
TEMPERATURES SHOULD OCCUR BEGINNING MONDAY AS THE HIGH SHIFTS
EASTWARD AND THE AIR MASS CONTINUES TO MODIFY. THE GFS...ECMWF...
AND EKD MOS SUPPORT HIGHS IN THE UPPER 70S TO AROUND 80 TUESDAY
THROUGH THURSDAY.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
REGIONAL RADAR LOOP SHOWS AN AREA OF SHOWERS IN THE UPSTATE AND
SHOWERS AND A FEW THUNDERSTORMS EXTENDING SOUTHWESTWARD THROUGH
GEORGIA. SHOULD SEE AT LEAST SCATTERED SHOWERS REACHING THE TAF
SITES BY MIDDAY...BUT BETTER CHANCE DURING THE AFTERNOON INTO THE
EVENING HOURS. CURRENT OBSERVATIONS SHOW MAINLY VFR CONDITIONS IN
THE UPSTATE WHICH INCREASES CONFIDENCE THAT TAF SITES MAY REMAIN
VFR THROUGH MUCH OF THE MORNING. LAMP GUIDANCE INDICATES
CONDITIONS DETERIORATING TO MVFR EARLY THIS AFTERNOON AND
REMAINING MVFR OR IFR THROUGH THE END OF THE TAF PERIOD...WHILE
NAM INDICATES A PERIOD OF CIGS ABOVE 3000 FEET DURING THE
EARLY AFTERNOON HOURS. WILL LEAN A BIT MORE TOWARDS THE MORE
PESSIMISTIC LAMP FORECAST.
LATEST CAE VWP SHOWING 40 KT WIND AROUND 2 KFT EARLY THIS
MORNING...WITH LIGHT WINDS AT THE SURFACE. WILL MENTION LLWS FOR ALL
TAF SITES UNTIL AROUND 15Z THIS MORNING.
EXTENDED AVIATION OUTLOOK...CIG/VSBY RESTRICTIONS EXPECTED SATURDAY
AHEAD OF A COLD FRONT THAT WILL CROSS THE AREA LATE SATURDAY
AFTERNOON. BREEZY CONDITIONS IN THE WAKE OF THE FRONT SATURDAY
NIGHT INTO SUNDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
641 AM EDT FRI MAR 28 2014
.SYNOPSIS...
MOISTURE WILL BE HIGH AHEAD OF A SLOW MOVING FRONTAL SYSTEM. THE
FRONT WILL MOVE THROUGH THE FORECAST AREA LATE SATURDAY. HIGH
PRESSURE AND DRIER CONDITIONS WILL PREVAIL SUNDAY AND MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
TODAY...A MOIST SOUTHERLY FLOW AND ISENTROPIC LIFT SHOULD HELP SUPPORT
SHOWERS TODAY. THE NAM AND GFS MOS PLUS RADAR TRENDS SUPPORT HIGH
POPS. BASED TIMING ON RADAR TRENDS AND THE LATEST HRRR. CLOUDINESS
AND SHOWERS SHOULD LIMIT INSTABILITY. THE NAM INDICATES JUST WEAK
INSTABILITY. THE HRRR AND SATELLITE TRENDS SUPPORT KEEPING THE
STRONGER CONVECTION SOUTH OF THE FORECAST AREA. EXPECT MAINLY
SHOWERS INSTEAD OF THUNDERSTORMS. USED THE COOLER TEMPERATURE
GUIDANCE BECAUSE OF CLOUDINESS.
TONIGHT...THE MOIST SOUTHERLY FLOW AND ISENTROPIC LIFT SUPPORT
CONTINUED HIGH POPS TONIGHT. COVERAGE MAY INCREASE TOWARD MORNING
AHEAD OF A MID-LEVEL SHORTWAVE TROUGH. COOLING ALOFT ASSOCIATED
WITH THE UPPER TROUGH SUPPORTS A HIGHER CHANCE OF THUNDERSTORMS
TOWARD MORNING. SHEAR WILL BE ON THE INCREASE INDICATING WELL-
ORGANIZED THUNDERSTORMS MAY OCCUR BUT THE NAM SUGGESTS ANY
SURFACE-BASED INSTABILITY WILL REMAIN WEAK THROUGH THE NIGHT. THE
DIURNAL TIMING SHOULD ALSO HELP LIMIT INSTABILITY. THEREFORE...THE
RISK OF SEVERE THUNDERSTORMS APPEARS LOW AT THIS TIME. THE WARMER
TEMPERATURE GUIDANCE APPEARS BETTER BECAUSE OF CLOUDINESS.
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
SATURDAY...MOISTURE SHOULD BE HIGH AHEAD OF THE COLD FRONT
SATURDAY. THE NAM INDICATES THE DEEPEST MOISTURE EARLY SATURDAY.
THE GFS AND ECMWF SHOW THE DEEPEST MOISTURE AROUND THE MIDDLE OF
THE DAY AHEAD OF THE COLD FRONT. THE MODELS WERE MORE CONSISTENT
WITH COLD FRONTAL PASSAGE LATE IN THE DAY OR EVENING. WE
MAINTAINED LIKELY POPS DURING MUCH OF THE DAY WITH THE TIMING
DIFFICULT BECAUSE ISENTROPIC LIFT APPEARS GREATER IN THE
MORNING...BUT CONVERGENCE AHEAD OF THE COLD FRONT SHOULD BE HIGHER
DURING THE AFTERNOON. SHEAR WILL BE HIGH. THE MODELS INDICATE H85
WINDS OF 35 TO 40 KNOTS. THE NAM INDICATES SURFACE-BASED LI/S NEAR
-3 DURING THE AFTERNOON. THERE WILL BE A THREAT OF SEVERE
THUNDERSTORMS BECAUSE OF THIS SHEAR AND INSTABILITY. ANY LINGERING SHOWERS
AND THUNDERSTORMS SHOULD END FROM WEST TO EAST SATURDAY EVENING
AS DRYING BECOMES DOMINATE BEHIND THE COLD FRONT. WE USED THE
GUIDANCE CONSENSUS FOR THE TEMPERATURE FORECAST.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
THE GFS AND ECMWF INDICATE DRY HIGH PRESSURE SHOULD DOMINATE
DURING MUCH OF THE PERIOD. MOISTURE SHOULD BE ON THE INCREASE LATE
IN THE PERIOD AHEAD OF A COLD FRONT. THE COOLEST NIGHT SHOULD BE
SUNDAY NIGHT. STRONG NOCTURNAL COOLING SHOULD OCCUR WITH DRY HIGH
PRESSURE OVERHEAD AND LIGHT WINDS. AN AVERAGE OF THE GFS...ECMWF
AND EKD MOS SUPPORTS LOWS MAINLY IN THE UPPER 30S. FROST WILL BE
POSSIBLE MAINLY IN THE NORMALLY COLDER LOCATIONS. WARMER
TEMPERATURES SHOULD OCCUR BEGINNING MONDAY AS THE HIGH SHIFTS
EASTWARD AND THE AIR MASS CONTINUES TO MODIFY. THE GFS...ECMWF...
AND EKD MOS SUPPORT HIGHS IN THE UPPER 70S TO AROUND 80 TUESDAY
THROUGH THURSDAY.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS LOW-LEVEL MOISTURE INCREASES...MODEL GUIDANCE SUGGESTING MVFR
CIGS DEVELOPING EARLY THIS MORNING. THERE IS THE POSSIBILITY OF IFR
CEILINGS AROUND SUNRISE...BUT CONFIDENCE TOO LOW TO INCLUDE. SHOULD
SEE AT LEAST SCATTERED SHOWERS DEVELOPING BY MIDDAY...BUT BETTER
CHANCE DURING THE AFTERNOON INTO THE EVENING HOURS. LAMP GUIDANCE
INDICATE MVFR CIGS CONTINUING THROUGH THE END OF THE TAF
PERIOD...WHILE NAM INDICATES A PERIOD OF CIGS ABOVE 3000 FEET DURING
THE AFTERNOON HOURS. WILL LEAN A BIT MORE TOWARDS THE MORE
PESSIMISTIC LAMP FORECAST.
LATEST CAE VWP SHOWING 40 KT WIND AROUND 2 KFT EARLY THIS
MORNING...WITH LIGHT WINDS AT THE SURFACE. WILL MENTION LLWS FOR ALL
TAF SITES UNTIL AROUND 15Z THIS MORNING.
EXTENDED AVIATION OUTLOOK...CIG/VSBY RESTRICTIONS EXPECTED FRIDAY
NIGHT INTO SATURDAY AHEAD OF COLD FRONT THAT WILL CROSS THE AREA LATE
SATURDAY AFTERNOON. BREEZY CONDITIONS IN THE WAKE OF THE FRONT
SATURDAY NIGHT INTO SUNDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
346 AM EDT FRI MAR 28 2014
.SYNOPSIS...
MOISTURE WILL BE HIGH AHEAD OF A SLOW MOVING FRONTAL SYSTEM. THE
FRONT WILL MOVE THROUGH THE FORECAST AREA LATE SATURDAY. HIGH
PRESSURE AND DRIER CONDITIONS WILL PREVAIL SUNDAY AND MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
TODAY...A MOIST SOUTHERLY FLOW AND ISENTROPIC LIFT SHOULD HELP SUPPORT
SHOWERS TODAY. THE NAM AND GFS MOS PLUS RADAR TRENDS SUPPORT HIGH
POPS. BASED TIMING ON RADAR TRENDS AND THE LATEST HRRR. CLOUDINESS
AND SHOWERS SHOULD LIMIT INSTABILITY. THE NAM INDICATES JUST WEAK
INSTABILITY. THE HRRR AND SATELLITE TRENDS SUPPORT KEEPING THE
STRONGER CONVECTION SOUTH OF THE FORECAST AREA. EXPECT MAINLY
SHOWERS INSTEAD OF THUNDERSTORMS. USED THE COOLER TEMPERATURE
GUIDANCE BECAUSE OF CLOUDINESS.
TONIGHT...THE MOIST SOUTHERLY FLOW AND ISENTROPIC LIFT SUPPORT
CONTINUED HIGH POPS TONIGHT. COVERAGE MAY INCREASE TOWARD MORNING
AHEAD OF A MID-LEVEL SHORTWAVE TROUGH. COOLING ALOFT ASSOCIATED
WITH THE UPPER TROUGH SUPPORTS A HIGHER CHANCE OF THUNDERSTORMS
TOWARD MORNING. SHEAR WILL BE ON THE INCREASE INDICATING WELL-
ORGANIZED THUNDERSTORMS MAY OCCUR BUT THE NAM SUGGESTS ANY
SURFACE-BASED INSTABILITY WILL REMAIN WEAK THROUGH THE NIGHT. THE
DIURNAL TIMING SHOULD ALSO HELP LIMIT INSTABILITY. THEREFORE...THE
RISK OF SEVERE THUNDERSTORMS APPEARS LOW AT THIS TIME. THE WARMER
TEMPERATURE GUIDANCE APPEARS BETTER BECAUSE OF CLOUDINESS.
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
SATURDAY...MOISTURE SHOULD BE HIGH AHEAD OF THE COLD FRONT
SATURDAY. THE NAM INDICATES THE DEEPEST MOISTURE EARLY SATURDAY.
THE GFS AND ECMWF SHOW THE DEEPEST MOISTURE AROUND THE MIDDLE OF
THE DAY AHEAD OF THE COLD FRONT. THE MODELS WERE MORE CONSISTENT
WITH COLD FRONTAL PASSAGE LATE IN THE DAY OR EVENING. WE
MAINTAINED LIKELY POPS DURING MUCH OF THE DAY WITH THE TIMING
DIFFICULT BECAUSE ISENTROPIC LIFT APPEARS GREATER IN THE
MORNING...BUT CONVERGENCE AHEAD OF THE COLD FRONT SHOULD BE HIGHER
DURING THE AFTERNOON. SHEAR WILL BE HIGH. THE MODELS INDICATE H85
WINDS OF 35 TO 40 KNOTS. THE NAM INDICATES SURFACE-BASED LI/S NEAR
-3 DURING THE AFTERNOON. THERE WILL BE A THREAT OF SEVERE
THUNDERSTORMS BECAUSE OF THIS SHEAR AND INSTABILITY. ANY LINGERING SHOWERS
AND THUNDERSTORMS SHOULD END FROM WEST TO EAST SATURDAY EVENING
AS DRYING BECOMES DOMINATE BEHIND THE COLD FRONT. WE USED THE
GUIDANCE CONSENSUS FOR THE TEMPERATURE FORECAST.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
THE GFS AND ECMWF INDICATE DRY HIGH PRESSURE SHOULD DOMINATE
DURING MUCH OF THE PERIOD. MOISTURE SHOULD BE ON THE INCREASE LATE
IN THE PERIOD AHEAD OF A COLD FRONT. THE COOLEST NIGHT SHOULD BE
SUNDAY NIGHT. STRONG NOCTURNAL COOLING SHOULD OCCUR WITH DRY HIGH
PRESSURE OVERHEAD AND LIGHT WINDS. AN AVERAGE OF THE GFS...ECMWF
AND EKD MOS SUPPORTS LOWS MAINLY IN THE UPPER 30S. FROST WILL BE
POSSIBLE MAINLY IN THE NORMALLY COLDER LOCATIONS. WARMER
TEMPERATURES SHOULD OCCUR BEGINNING MONDAY AS THE HIGH SHIFTS
EASTWARD AND THE AIR MASS CONTINUES TO MODIFY. THE GFS...ECMWF...
AND EKD MOS SUPPORT HIGHS IN THE UPPER 70S TO AROUND 80 TUESDAY
THROUGH THURSDAY.
&&
.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS FORECAST FOR THE NEXT SEVERAL HOURS. AS LOW-LEVEL
MOISTURE INCREASES LATE TONIGHT...LAMP GUIDANCE AND MAV/MET MOS
SUGGESTING MVFR CIGS DEVELOPING DURING THE PRE-DAWN HOURS. THERE IS
THE POSSIBILITY OF IFR CEILINGS AROUND SUNRISE...BUT CONFIDENCE TOO
LOW TO INCLUDE. SHOULD SEE AT LEAST SCATTERED SHOWERS DEVELOPING BY
MIDDAY...BUT BETTER CHANCE DURING THE AFTERNOON INTO THE EVENING
HOURS. LAMP GUIDANCE INDICATE MVFR CIGS CONTINUING THROUGH THE END
OF THE TAF PERIOD...WHILE NAM INDICATES A PERIOD OF CIGS ABOVE 3000
FEET DURING THE AFTERNOON HOURS. WILL LEAN A BIT MORE TOWARDS THE
MORE PESSIMISTIC LAMP FORECAST.
INCREASING SOUTHERLY LOW LEVEL JET OVERNIGHT. LATEST CAE VWP SHOWING
40-45 KT WIND AROUND 2 KFT EARLY THIS MORNING. WILL MENTION LLWS FOR
ALL TAF SITES UNTIL AROUND 15Z THIS MORNING.
EXTENDED AVIATION OUTLOOK...CIG/VSBY RESTRICTIONS EXPECTED FRIDAY
NIGHT INTO SATURDAY AHEAD OF COLD FRONT THAT WILL CROSS THE AREA LATE
SATURDAY AFTERNOON. BREEZY CONDITIONS IN THE WAKE OF THE FRONT
SATURDAY NIGHT INTO SUNDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
954 PM CDT SAT MAR 29 2014
.DISCUSSION...
321 PM CDT
MAIN FORECAST CONCERNS/CHALLENGES ARE WITH SHOWER/THUNDER CHANCES
MONDAY AND MONDAY NIGHT...AND THEN WITH ACTIVE WEATHER TO CONTINUE
THROUGH LATE IN THE WORK WEEK.
CHALLENGES IN THE NEAR TERM HAVE BEEN WITH THE LINGERING AND SLOW
MOVING LOW STRATUS STILL IN PLACE OVER MUCH OF THE CWA...AS WELL
AS RESULTANT HIGH TEMPERATURES. LATEST VISIBLE SATELLITE IMAGERY
DEPICTING A SLOW SOUTH/SOUTHEAST MOVEMENT TO THE STRATUS BUT WITH
SOME PROGRESS BEING MADE. ALTHOUGH...THIS PROGRESS IS SLOW AND
COINCIDING WITH FURTHER DIURNAL DEVELOPMENT ON THE NORTHERN
PERIPHERY OF THIS CLOUD DECK. MADE EDITS THIS AFTERNOON TO SLOW
THE CLEARING TREND THROUGH 00Z AND WITH AT LEAST PARTLY CLOUDY
SKIES FOR THE SOUTHERN THIRD OF THE CWA THROUGH EARLY THIS
EVENING...BEFORE CLEARING CONTINUES AND MOSTLY CLEAR SKIES
EXPECTED TO PREVAIL OVERNIGHT. DID DROP HIGH TEMPS A COUPLE OF
DEGREES IN SOME PLACES EARLIER THIS AFTERNOON DUE TO THIS CLOUD
COVER...WITH TEMPS STAYING IN THE UPPER 30S OR AROUND 40 UNDER THE
CLOUD COVER AND LOW TO MID 40S FOR AREAS WHICH HAVE OBSERVED MORE
SUNSHINE WITHIN THE LAST COUPLE OF HOURS. ALTHOUGH...ALL LOCATIONS
WILL OBSERVE FALLING TEMPS THIS EVENING AS THE DEPARTING CLOUD
COVER THIS AFTERNOON AND EVENING ONLY AIDS IN A COLD NIGHT
TONIGHT. SURFACE HIGH TO THE WEST/NORTHWEST WILL SHIFT OVERHEAD
TONIGHT WITH WINDS DIMINISHING AND DESPITE WAA BEGINNING
OVERNIGHT...TEMPS ANTICIPATED TO FALL INTO THE 20S ACROSS THE CWA.
MID/UPPER 20S ARE LIKELY FOR MOST LOCATIONS...OUTSIDE OF THE
CITY...WITH SOME LOCATIONS POSSIBLE DIPPING INTO THE LOWER 20S.
QUIET CONDITIONS EXPECTED SUNDAY/SUNDAY NIGHT AS UPPER LEVEL
RIDGING IS ONGOING ACROSS THE REGION. CONTINUED WAA WILL HELP A
WARMER AIRMASS TO SPREAD OVER THE CWA ON SUNDAY WITH TEMPS
EXPECTED TO RISE AROUND 60. DID MAKE SOME MINOR ADJUSTMENTS TO MAX
TEMPS MAINLY TO ACCOUNT FOR PERSISTENT ONSHORE FLOW FOR AREAS IN
CHICAGO AND NORTHWARD...KEEPING TEMPS IN THE LOW TO MID 50S. AFTER
A MILD NIGHT SUNDAY NIGHT...PERSISTENT WAA WILL PROVIDE WELL ABOVE
NORMAL HIGHS IN THE MID TO UPPER 60S. ONSHORE FLOW NOT ANTICIPATED
SO MOST LOCATIONS LIKELY TO OBSERVE THIS WARMTH. WILL HAVE
INCREASING CLOUD COVER ON MONDAY IN ADVANCE OF VORT MAX AND
ATTENDANT SURFACE LOW MOVING EAST OVER THE CENTRAL CONUS. GUIDANCE
IN AGREEMENT WITH DRY CONDITIONS MONDAY MORNING AND THEN WITH
INCREASING CHANCES FOR PRECIP INTO THE AFTERNOON...THOUGH
PRIMARILY FOR THE WESTERN CWA. FOR MONDAY AFTERNOON INTO MONDAY
EVENING...NOT OVERLY CONFIDENT WITH POPS DURING THIS PERIOD AND
HAVE ONLY MADE MINOR CHANGES TO LOW CHANCE/CHANCE POPS. THIS IS
MAINLY DUE TO THE FACT THAT CONFIDENCE IS NOT HIGH WITH REGARDS TO
OVERALL COVERAGE OF PRECIP. WITH LARGE SCALE FORCING FOR ASCENT
SPREADING OVER THE AREA ON MONDAY AS WELL AS MOISTURE INCREASING
OUT AHEAD OF SURFACE LOW AND COLD FRONT...DEVELOPMENT SHOULD NOT
BE TOO MUCH OF AN ISSUE...AND EXPECT POPS TO LIKELY CHANGE DURING
THIS PERIOD WITH SUCCESSIVE FORECASTS. STILL NOT OVERLY CONFIDENT
WITH THUNDER DEVELOPMENT AS WELL...AND SO HAVE MADE LITTLE CHANGES
DURING THIS TIME KEEPING CHANCE THUNDER IN THE GRIDS. WILL NEED TO
MONITOR THE EXTENT OF THE MOISTURE RETURN AND RESULTANT
INSTABILITY...WHICH AT THIS TIME IS APPEARING RATHER WEAK.
WILL STILL NEED TO MONITOR AN EXPECTED ACTIVE WEATHER PATTERN FOR
THIS NEXT WEEK AS GUIDANCE IS IN AGREEMENT WITH SEVERAL FEATURES
PUSHING ACROSS THE REGION. ALTHOUGH...TIMING AND EVOLUTION
AGREEMENT IS LACKING WHICH WILL BE KEY WITH PRECIP TYPE...WHICH
COULD STILL BE OF FROZEN FORM VERY LATE IN THE FORECAST PERIOD.
RODRIGUEZ
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* SOUTH SOUTHEAST WINDS SUNDAY INCREASING TO OVER 10 KT.
//DISCUSSION...UPDATED 00Z...
A HIGH PRESSURE RIDGE CENTERED ACROSS THE MISSISSIPPI RIVER LATE
THIS AFTERNOON WILL MOVE OVER AREA TAF SITES BY MID EVE AND
PERSIST THROUGH DAYBREAK SUNDAY. DIMINISHING WIND SPEEDS AND A
CLEARING SKY WILL BE THE RESULT. THERE WILL BE POTENTIAL FOR FOG
DEVELOPMENT PRIMARILY IN THOSE AREAS THAT CLEARED THE LATEST
TODAY DUE TO ELEVATED DEW POINTS AND SLIGHTLY COOLER TEMPS. THE
MOST VULNERABLE AIRPORT WILL THUS BE GYY AND HAVE INCLUDED MENTION
OVERNIGHT...THOUGH TEMPORARY IFR FOG WOULD CONCEIVABLY BE
POSSIBLE. SUNDAY WILL SEE SOUTHEAST WINDS BECOMING NEAR DUE SOUTH
BY AFTERNOON AND INCREASING IN SPEED WITH SPORADIC GUSTS IN THE
AFTERNOON ACROSS NORTH CENTRAL AND POSSIBLY NORTHEAST IL. A LAKE
BREEZE IS LIKELY TO DEVELOP OVER CHICAGO BUT WHETHER IT CAN REACH
FAR ENOUGH WEST AS MDW AND ORD WILL BE CLOSE. HAVE OPTED TO NOT
INDICATE A WIND SHIFT AT THOSE TWO AIRPORTS...WHILE LEANING WITH
PREVAILING WINDS JUST EAST OF SOUTH...THOUGH WOULD NOT BE
SURPRISED TO SEE THEM VARY BETWEEN 160 AND 190 IN THE AFTERNOON.
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* HIGH IN WINDS THROUGH SUNDAY MORNING. MEDIUM THEREAFTER...AS
DIRECTION COULD BRIEFLY CHANGE TO EAST SOUTHEAST SUNDAY
AFTERNOON WITH A LAKE BREEZE.
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...NEAR DUE SOUTH WINDS GUSTING TO AROUND 30 KT IN THE
AFTERNOON. CHC OF TSRA DURING THE EVE AND A SLGT CHC
OF LIGHT RAIN/SNOW DURING THE OVERNIGHT.
TUESDAY...MORNING MVFR POSSIBLE.
WEDNESDAY...EAST FLOW WITH RAIN AND MVFR/IFR LIKELY.
THURSDAY...EAST FLOW WITH CHC OF RAIN AND POSSIBLE IFR.
FRIDAY...CHC OF RAIN DURING THE DAY. SLGT CHC OF RAIN/SNOW DURING
THE NIGHT.
MTF
&&
.MARINE...
251 PM CDT
NORTH-NORTHEASTERLY ONSHORE FLOW ACROSS NORTHEASTERN ILLINOIS AND
NORTHWESTERN INDIANA CONTINUES UP AROUND 20S OUT AHEAD OF AN AREA OF
HIGH PRESSURE. THIS FLOW IS BIT STRONGER THAN PREVIOUSLY
THOUGH...AND AS A CONSEQUENCE OF THIS...I HAVE ISSUED A SMALL CRAFT
ADVISORY THROUGH THIS EVENING...MAINLY FOR THE EXPECTATION THAT
WAVES ARE AT OR JUST ABOVE THE 4 FOOT MARK. THESE WINDS WILL ABATE
THIS EVENING...THEN GRADUALLY BECOME EAST-SOUTHEASTERLY OVERNIGHT
TONIGHT AS THE SURFACE RIDGE SHIFTS OVER THE LAKE.
LOW PRESSURE WILL BE IN THE PROCESS OF DEVELOPING ACROSS THE CENTRAL
HIGH PLAINS ON SUNDAY...AND THIS WILL RESULT IN A CONTINUAL
SOUTH-SOUTHEASTERLY FLOW PATTERN ACROSS THE LAKE FOR THE NEXT COUPLE
OF DAYS. THE LOW IS EXPECTED TO TRACK EAST-NORTHEASTERLY TO THE
UPPER MISSISSIPPI VALLEY BY LATE MONDAY EVENING...THEN SHIFT ACROSS
THE UPPER GREAT LAKES BY TUESDAY EVENING. OVERALL...THIS WILL RESULT
IN INCREASING SOUTHERLY WINDS MONDAY AND INTO MONDAY
EVENING...LIKELY TO AROUND 30 KT. OVERALL...IT APPEARS THAT WARMER
AIR MOVING OVER THE LAKE WILL RESULT IN A STABLE MARINE
LAYER...WHICH WOULD RESULT IN LOWER CHANCES FOR GALES.
HOWEVER...SOME STRONGER WINDS NEARLY GALE FORCE ARE POSSIBLE WITH
THIS SYSTEM...ESPECIALLY MONDAY NIGHT AS THE LOW AND COLD FRONT
APPROACH THE LAKE. WESTERLY FLOW WILL SET UP TUESDAY IN THE WAKE OF
THIS SYSTEM.
ANOTHER STORM SYSTEM LOOKS TO TAKE AIM ON THE LOWER GREAT LAKES
LATER IN THE PERIOD...AROUND THURSDAY. THIS COULD RESULT IN A PERIOD
OF SOME ENHANCED NORTHEASTERLY WINDS INTO THE END OF THE UP COMING
WEEK.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 10 PM SATURDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
[top]
Area Forecast Discussion
National Weather Service Lincoln IL
822 PM CDT Sat Mar 29 2014
.DISCUSSION...
ISSUED 822 PM CDT Sat Mar 29 2014
Have made adjustments to sky grids to push clearing a bit faster
than current package. Otherwise going forecast looks good.
Surface ridge moving into forecast area attm and winds have
decoupled despite significant northwest winds above the boundary layer
associated with strengthening system over the central
Appalachians. This flow above developing inversion continues to
erode cloud cover and advect drier air into Illinois from
northwest to southeast. Trapped moisture under the inversion may
lead to some patchy ground fog. Attm, it appears that lowest vsbys
should be around 3SM so will leave out of grids/zones but keep it
in eastern TAF sites. Latest Lamp guidance in good agreement with
ongoing forecast for tonight`s lows.
Barker
&&
.AVIATION...
ISSUED 604 PM CDT Sat Mar 29 2014
MVFR CIGs eroding slowly from northwest to southeast as ridge west
of the Mississippi River builds into Illinois. At 23z only KBMI
and KCMI retain a CIG and satellite imagery suggests KBMI should
clear shortly. Improvement at KCMI may be a bit slower. Pilot
report from 2225z suggests stratus remains near 1500 ft thick and
with sun setting, rate of thinning may slow. Will hold on to MVFR
CIG there til 03z.
Also given the slow clearing and ridge moving overhead, could see
the redevelopment of ground fog, particularly at KCMI given the
NAM Bufr sounding. For now will keep mention of BR out of I-55
terminals and KPIA where sfc dewpoints have been able to fall
slightly with this afternoon`s advection from the north. However,
will need to throw in a tempo for MVFR fog for late tonight at
KDEC and KCMI.
Ridge pushes east on Sunday and models suggest some higher CIGs
developing during the afternoon once the mid-level ridge
inflection point moves east of the terminals ahead of a
developing system over the central high plains. Since the CIGs
should be above operational significant heights will not break off
a new grouping attm. With ridge pushing east, south winds develop
on Sunday and gusty conditions should return. particularly at western
terminals.
Barker
&&
.PREV DISCUSSION...
ISSUED 228 PM CDT Sat Mar 29 2014
The progressive weather pattern will provide active weather next
week as several storm systems affect Illinois. The latter half of
this weekend looks pleasant with plenty of sunshine pushing temps
above normal. However, by Monday afternoon the first system will
bring chances of rain, and the onset of a return to cooler
conditions. Heavier rains in the Wed to Thur time frame could
accumulate between 1-2" in some locations. Localized flooding may
develop.
SHORT TERM...Tonight through Sunday night.
Low clouds have been keeping high temps generally below forecast
highs this afternoon. A narrow break in the cloud cover allowed
Peoria to spike up about 10 degrees in a couple hours, and create
a large temperature gradient over short distances in our forecast
area. The RAP and HRRR layer RH indicate that some clearing should
continue west of I-57 between 23z and 03z. Lows tonight will be
dependent on cloud cover. Areas east of I-57 may remain cloudy
until just after midnight as NE surface winds continue to drag low-
level moisture from the Great Lakes into eastern IL. Even a few
hours of clearing later tonight should allow eastern areas to cool
off to near guidance lows, especially with surface dewpoints
dipping into the upper 20s in many locations.
Sunday will see mid level temps climb 5 to 7C during the day as an
upper level ridge axis advances into eastern IL by 00z/7pm Monday.
Near full sunshine should combine with increasing south winds to
push highs about 10 to 15 deg above normal (60s), which will be a
welcome taste of Spring. An tightening pressure gradient ahead of
the next system will keep south winds up in the 10 to 20 mph range
even Sunday night. So despite clear skies Sunday night, south
winds will keep a mixed boundary layer and allow lows to be in the
upper 40s west and around 40 east.
LONG TERM...Monday through Saturday.
Increasing clouds on Monday will not prohibit highs from climbing
well into the 60s for one more day, as south-southeast winds
increase into the 25 to 35 mph range. By Monday afternoon, a
parent low pressure system will advance from eastern Nebraska to
southeastern Minn, as a cold front reaches the western border of
IL by 00z/7pm Monday. Pre-frontal storms will have a high amount
of wind shear and storm relative helicity available, along with
steep lapse rates, but a limited amount of moisture. Forecast
soundings show the best instability may be at or above 750 mb, so
any thunderstorms will be elevated to begin. Due the strong jet
dynamics and wind shear with this system, some of the storms could
begin rotating and produce hail and strong winds Monday afternoon
and evening ahead of the cold front.
Showers and storms should end from west to east by midnight in the
post-frontal subsidence and dry air intrusion. Clouds will likely
clear out behind the line of precip, so lows in the NW could dip
below freezing, while southeast areas remain in the low 40s.
The brief pocket of cold air is forecast to brush across N IL late
Mon night and Tues morning, which will keep highs about 10-15 deg
colder than Monday. High temps will range from around 50 near
Galesburg to around 60 by Lawrenceville.
Return flow behind the cooler high pressure will bring increasing
moisture Tuesday night, with a few showers possible before sunrise
on Wednesday. Thunderstorm chances will increase along and south
of a warm front that is expected to develop directly across
central IL from west to east. Storm chances will be higher in the
warm sector roughly south of a line from Rushville to Champaign.
Instability may have a better chance of being based closer to the
surface as dewpoints climb into the 50s Wed night south of the
warm front, which will be close to overnight low temps.
Precipitable water values are expected to climb over an inch Wed
night through Thursday as low pressure tracks northeast along the
warm front. Locally heavy rain may occur in any thunderstorms,
with training of storms over the same area also boosting rainfall
amounts. Localized flooding could develop in low areas, as
rainfall amounts possibly reach between 1 and 2 inches by Thursday
afternoon.
A wide range of temps will occur across C IL from north to south
from Tues night through Thursday as the warm front lingers across
the middle of the area. The temp spreads could be 20 to 25 degrees
from north to south for highs and lows.
There is a spread of solutions for how the surface and upper level
systems progress from after Thursday. The GFS lingers the upper
trough farther west Thurs night, then brings a secondary surface
low and another round of rain showers across IL on Friday. The
ECMWF is more progressive and drys out the air column after the
low on Thursday. So low chance and slight chance PoPs were
included Thurs night and Friday to account for a slower
progression.
There is some agreement that another push of cold air will keep
temps below normal for Friday and Saturday, with Saturday looking
dry at this time.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1253 PM CDT FRI MAR 28 2014
.DISCUSSION...
1018 AM CDT
HAVE MADE SOME ADJUSTMENTS TO SKY GRIDS TODAY TO BE A BIT LESS
OPTIMISTIC WITH CLEARING. LOW LEVEL MOISTURE/STRATUS IS CURRENTLY
TRAPPED UNDER A FAIRLY SHARP INVERSION AND INVERSION IS LIKELY TO
PERSIST NOT OFFERING MUCH HOPE FOR BETTER MIXING. CLEARING LINE
OVER CENTRAL WISCONSIN IS MAKING FAIRLY QUICK PROGRESS SOUTHWARD
AND WILL PROBABLY MAKE IT INTO AT LEAST OUR NORTHERN CWA THIS
AFTERNOON...THOUGH WITH LOW LEVEL FLOW SLACKENING THIS AFTERNOON
AND VEERING NE WOULD EXPECT THIS CLEARING LINE TO SLOW DOWN A BIT.
ASSUMING CLOUD COVER LINGERS INTO THE AFTERNOON...TEMPERATURES
WILL BE SLOW TO RECOVER AND HAVE SHAVED A FEW DEGREES OFF GOING
HIGH TEMPS.
UPDATED GRIDS/TEXT PRODUCTS HAVE BEEN SENT.
IZZI
//PREV DISCUSSION...
323 AM CDT
TODAY...
SURFACE COLD FRONT IS CLEARING THE EASTERN COUNTIES IN THE CWA EARLY
THIS MORNING WHILE A SECONDARY TROUGH IS DIGGING ACROSS NORTHERN
ILLINOIS WITH WINDS TURNING SHARPLY TO THE NNW WITH GUSTS WELL INTO
THE 20 KT RANGE. SHOWERS BEHIND THIS TROUGH WILL SWEEP ACROSS
NORTHERN ILLINOIS AND NORTHWEST INDIANA...EXITING TO THE EAST BY MID
TO LATE MORNING. BREEZY CONDITIONS THIS MORNING SHOULD GRADUALLY
TAPER THROUGH THE DAY AS THE AS THE LOW LIFTS TOWARDS QUEBEC AND
FILLS. TEMPS INTO THE MID TO UPPER 40S ARE EXPECTED THIS
AFTERNOON...BUT A LAKE BREEZE WILL TURN WINDS NORTHEASTERLY AND COOL
TEMPS BACK INTO THE 30S ALONG THE LAKE.
THIS WEEKEND...
LOW PRESSURE WILL LIFT FROM ARKLATEX INTO THE UPPER OHIO VALLEY BY
MIDDAY SATURDAY. BEST CHANCES FOR PRECIP WILL BE SOUTH OF I-80
ESPECIALLY IN NORTHWEST INDIANA...AND FOR NOW IT APPEARS AREAS NORTH
WILL REMAIN DRY. GFS INDICATES WET BULBS DROPPING BELOW ZERO THROUGH
THE COLUMN AROUND OR BEFORE THE ONSET OF PRECIP INDICATE ALL SNOW.
NAM SOUNDINGS ON THE OTHER HAND SHOW SLIGHTLY WARMER TEMPS ALOFT
HINTING AT THE POSSIBILITY FOR RAIN/SNOW MIX...THOUGH SREF P-TYPE
PROBABILITY INDICATES BETTER CHANCES FOR SNOW. COMING OFF HIGHS IN
THE UPPER 40S IN AREAS MOST LIKELY TO SEE PRECIP...AND OVERNIGHT
LOWS SOUTH OF 80 AT OR EVEN SLIGHTLY ABOVE FREEZING...THE LIKELIHOOD
OF ACCUMULATING SNOW IS LOW AND WOULD LIKELY BE CONFINED TO THE
GRASS. IN ADDITION...GIVEN THE MARGINAL SOUNDINGS...SNOW PRODUCTION
WOULD BE INEFFICIENT. WILL MAINTAIN RAIN/SNOW MIX IN THE FORECAST
FOR NOW GIVEN THE CURRENT UNCERTAINTY.
HIGH PRESSURE WILL THEN TRANSLATE ACROSS THE REGION OVER THE
REMAINDER OF THE WEEKEND RESULTING IN DRY WEATHER FROM SATURDAY
AFTERNOON ON. H85 THERMAL TROUGH WILL APPROACH THE REGION ON
SATURDAY...THOUGH SUBSIDENCE ALOFT SETTLING OVER THE UPPER MIDWEST
THROUGH THE DAY SATURDAY WILL RESULT IN DRYING AND WARMING OF THE
MID LEVELS WHICH WILL HELP MODULATE THE COLDER AIRMASS MOVING
OVERHEAD. WITH AFTERNOON SUNSHINE...EXPECT AREAS AWAY FROM THE LAKE
TO RISE INTO THE MID TO UPPER 40S AGAIN...WITH A FEW 50S MAINLY
SOUTH OF I-80. ALONG THE LAKE FRONT...A BREEZE OFF THE LAKE THROUGH
THE DAY WILL KEEP TEMPERATURES MUCH COOLER...IN THE MID 30S. THE
SURFACE RIDGE AXIS WILL PASS OVERHEAD SATURDAY NIGHT...AND SOUTHERLY
FLOW WILL RAMP UP THROUGH THE DAY SUNDAY AHEAD OF OUR NEXT AREA OF
LOW PRESSURE STARTING TO TAKE SHAPE OVER THE PLAINS. STRONG WARM
ADVECTION IS EXPECTED THROUGH THE DAY SUNDAY WHICH WILL RESULT IN
H85 TEMPS RISING TO AROUND 10C BY SUNDAY EVENING. SOUTHERLY WINDS
MAY TAKE ON A SLIGHT WESTERLY COMPONENT BY SUNDAY AFTERNOON...IN THE
190-200 DIRECTION...WHICH WITH THE INCREASING WINDS SHOULD HELP
STAVE OFF ANY LAKE BREEZE/LAKE COOLING SUNDAY. NAM/GFS SOUNDINGS
SHOW LOW TO MID 20 KT GUSTS POSSIBLE BY SUNDAY AFTERNOON.
TEMPERATURES SHOULD RISE TO AROUND 60 RIGHT UP TO THE LAKE FRONT
SUNDAY AFTERNOON.
MONDAY...
AFOREMENTIONED SURFACE LOW PROGGED TO LIFT FROM THE MID MISSOURI
VALLEY EARLY MONDAY INTO MN/WI MONDAY EVENING. LATEST GUIDANCE IN
DECENT AGREEMENT ON THE LOCAL AREA GETTING FULL WARM SECTOR ON
MONDAY. LEANED TOWARD WARMER SIDE OF GUIDANCE MONDAY WITH A BLEND OF
BIAS CORRECTED GEM AND ECMWF. THIS RESULTS IN LOW TO MID 60S AREA
WIDE MONDAY AFTERNOON...AND WITH A MODERATE-STRONG SSW WIND...DO NOT
ANTICIPATE ANY COOLING ALONG THE LAKE. A 60-70KT LOW LEVEL JET
FOCUSES STRONG CONVERGENCE ACROSS THE MID MISSOURI VALLEY SUNDAY
NIGHT...THEN AT 40-50 KT REFOCUSES TO OUR NORTH MONDAY
EVENING/NIGHT. ACROSS NORTHERN ILLINOIS IN THE WARM SECTOR...
INSTABILITY IS PRETTY MEAGER WITH A STRONG CAP IN PLACE...THOUGH
SOME DYNAMIC COOLING ASSOCIATED WITH NEGATIVELY TILTED H5 WAVE AND
EXIT REGION OF UPPER JET MAY RESULT IN SOME SCATTERED CONVECTION.
ALL-IN-ALL THOUGH...GIVEN THE UNFAVORABLE TIMING OF THE FRONT
OVERNIGHT...NOT TOO IMPRESSED WITH PRECIP CHANCES MONDAY AND TRIMMED
POPS FOR THIS PERIOD.
TUESDAY THROUGH THURSDAY...
PRETTY LOW CONFIDENCE IN THE DETAILS AT THIS POINT...BUT TUESDAY
THROUGH THURSDAY SHOULD BE AN ACTIVE PERIOD WITH A SERIES OF
DISTURBANCES MOVING ACROSS THE REGION. THERE REMAINS SIGNIFICANT
DIFFERENCES AT THIS POINT BETWEEN MODELS WITH RESPECT TO THE LOW
TRACK WHICH WILL DETERMINE TEMPS AND PRECIP TYPE. GFS INDICATES A
FASTER MORE SOUTHERLY LOW WHILE THE ECMWF HINTS AT A WARMER SOLUTION
WITH A DEEPER LOW THAT TRACKS FARTHER NORTH. FOR NOW...STAYED CLOSE
TO A CONSENSUS BLEND.
TUBELESS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* VARIABLE NORTH-NORTHWEST TO NORTH-NORTHEAST WINDS...TURNING
NORTHEAST MID/LATE AFTERNOON.
* CIGS AROUND 020 SCATTERING LATE THIS AFTERNOON OR EARLY THIS
EVENING.
* ANOTHER PERIOD OF LOWER CIGS POSSIBLE LATE TONIGHT/SATURDAY
MORNING...MVFR POSSIBLE.
MDB
//DISCUSSION...UPDATED 18Z...
LOW PRESSURE CONTINUES TO MOVE NORTHEAST ACROSS EASTERN ONTARIO
AND WESTERN QUEBEC LEAVING NORTHERLY WINDS IN ITS WAKE ACROSS THE
LOCAL AREA. WINDS WILL LIKELY BE VARIABLE BETWEEN NORTHWEST AND
NORTH INLAND OF THE LAKE THROUGH THE AFTERNOON THEN TURN LIGHT
NORTHEASTERLY THIS EVENING. AREAS CLOSER TO THE LAKE INCLUDING
ORD/MDW/GYY WILL LIKELY FLUCTUATE BETWEEN NORTHWEST AND NORTH-
NORTHEAST WITH GYY BECOMING STEADY NORTHEAST EARLY THIS AFTERNOON.
NOT AS CONFIDENCE IN IF STEADIER NORTHEAST WINDS WILL SET UP AT
ORD/MDW DURING THE AFTERNOON OT HOLD OFF UNTIL EVENING. CLOUD
COVER REMAINS ABUNDANT...WHICH MAY ALSO SLOW THE TIMING OF A SHIFT
TO NORTHEAST WINDS/LAKE BREEZE. WITH THE SOUTHWARD ADVANCE OF
CLEARING ACROSS SOUTHERN WISCONSIN SLOWING WILL KEEP MVFR CIGS
ACROSS THE TERMINALS THROUGH THE AFTERNOON THEN SCATTER/CLEAR
EARLY THIS EVENING.
AN UPPER TROUGH CROSSES THE AREA LATER TONIGHT BRINGING LOWERING
CIGS. CIGS SHOULD REMAIN LOWER END MVFR BUT A PERIOD OF MVFR IS
POSSIBLE. THERE IS ALSO A MINIMAL THREAT FOR SOME LIGHT SNOW OR
JUST FLURRIES OVERNIGHT BUT WILL KEEP THE TAF DRY. NORTHEAST WINDS
WILL PERSIST THROUGH SATURDAY WITH SKIES SCATTERING/CLEARING
DURING THE MID/LATE MORNING HOURS.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM CONFIDENCE IN WIND TRENDS...LOW-MEDIUM CONFIDENCE IN
TIMING OF SHIFT TO STEADIER NORTHEAST.
* HIGH CONFIDENCE IN MVFR CIGS THROUGH MID AFTERNOON...THEN LOW-
MEDIUM CONFIDENCE IN TIMING OF SCATTERING BEYOND THAT.
* MEDIUM CONFIDENCE THAT CIGS WILL REMAIN VFR OVERNIGHT/SATURDAY
MORNING.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...VFR. NORTHEAST WINDS TURNING SOUTHEAST.
SUNDAY...VFR. SOUTH WINDS.
MONDAY...CHANCE OF SHRA/TSRA LATE. MODERATE-STRONG SOUTH WINDS.
TUESDAY...VFR PROBABLE. WEST WINDS.
WEDNESDAY...CHANCE OF RAIN AND IFR/MVFR CIGS. NORTHEAST WINDS.
THURSDAY...CHANCE OF RAIN OR SNOW AND IFR/MVFR. NORTHEAST WINDS.
LENNING
&&
.MARINE...
307 AM CDT
A STRONG LOW PRESSURE SYSTEM IS EXITING THE AREA THIS MORNING
ACROSS LOWER MICHIGAN AND LAKE HURON. NORTHWEST TO NORTH GALES
WILL EASE QUICKLY THIS MORNING AS THE LOW PULLS AWAY AND THE
PRESSURE GRADIENT WEAKENS. A RIDGE WILL CROSS THE LAKE ON SATURDAY
BEFORE THE NEXT LOW PRESSURE SYSTEM STARTS TO APPROACH OUT OF THE
CENTRAL PLAINS. ALTHOUGH THIS LOW DOES NOT REACH THE LAKE UNTIL
TUESDAY...SOUTHERLY FLOW AHEAD OF THIS SYSTEM WILL DEVELOP BY
EARLY SUNDAY. A PERIOD OF GALES IS AGAIN POSSIBLE LATE MONDAY
INTO TUESDAY...ESPECIALLY ACROSS THE SOUTHERN HALF OF THE
LAKE...AS THE LOW MOVES THROUGH.
LENNING
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 2 PM FRIDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1231 PM CDT Fri Mar 28 2014
.DISCUSSION...
ISSUED 1014 AM CDT Fri Mar 28 2014
Updated forecast to lower highs a few degrees and increase cloud
cover mainly across central/northern CWA. 10 AM visible satellite
imagery showed a strip of clearing north of the Ohio River
extending into the far SE CWA, while farther north a thick blanket
of stratus/SC stretched back through most of MO/IA and southern
WI. HRRR and RAP RH trends in the 950-900 MB level suggest the
clearing over the far SE will slowly shift north towards I-72 by
late afternoon as southerly winds strengthen in that layer. This
clearing will be brief however as mid clouds ahead of next wave
developing in the Plains overspread the region later this
afternoon and evening. Brisk NW winds this morning to ease through
afternoon as low pressure pushes east of the Great Lakes and MSLP
gradient relaxes.
&&
.AVIATION...
ISSUED 1231 PM CDT Fri Mar 28 2014
Extensive area of MVFR SC blankets all terminals this afternoon.
Latest model trends show this will take until late afternoon and
early evening to erode from the south and have shifted TAFS
towards that timing. The next weather disturbance will quickly
shift northeast from the Plains this evening spreading mid level
clouds across the area. All models (except NAM being farthest
north outlier) bring precip as far north as the I-72 corridor
after midnight through 10-12Z. Thermal profiles are near rain/snow
threshold and with surface temps above freezing have -RASN in
forecast with slight visibility reduction. Questionable if
farthest north sites will receive any precip so have VCSH for BMI
and kept PIA dry. Ceilings are expected to be near MVFR during
this precip event. Initially light north winds this afternoon will
veer around to the northeast and increase in speed overnight
through Sat morning up to 10-15 kts in response to low pressure
tracking south of the Ohio Valley.
25
&&
.PREV DISCUSSION...
ISSUED 313 AM CDT Fri Mar 28 2014
SHORT TERM...Today through Sunday
Main forecast challenge in the immediate short-term will be timing
the departure of low clouds today. 07z/2am surface analysis shows
low pressure over southern Lake Michigan with cold front trailing
southward along the I-57 corridor. Extensive area of wrap-around
cloud cover is noted on IR satellite imagery blanketing Iowa,
northern Missouri, and western Illinois. With low-level flow
becoming northwesterly, these clouds will spill across central
Illinois early this morning. All model guidance suggests an
overcast start to the day, but how quickly the clouds clear out
remains in question. NAM forecast soundings indicate clouds will
mix out/dissipate between 15z and 18z. Latest HRRR hints at this
as well, although the process may be slower than the NAM
advertises. Given subsidence behind departing upper short-wave and
late March sun working on the low clouds, think skies will
temporarily clear around midday into the early afternoon. After
that, high clouds will quickly begin to increase ahead of the next
approaching system by mid to late afternoon.
Next forecast concern revolves around low pressure expected to
track from Texas into the Tennessee River Valley tonight. Models
have been having difficulty resolving how far north associated
precip will spread. 00z Mar 28 suite is still in disagreement,
with the GFS being the most aggressive in bringing precip furthest
north. Since GFS is often too bullish with light QPF events and
airmass will be drying today, think the NAM has a more realistic
handle on the situation. As such, will keep locations along and
north of a Jacksonville to Bloomington line dry tonight. Best rain
chances will be focused along/south of I-70 in closer proximity to
the low track, with POPs steadily decreasing further northwest.
Despite overnight lows in the middle to upper 30s, NAM forecast
soundings remain warm enough for rain. If colder/further north GFS
verifies, a rain/snow mix may be possible along the northern
fringe of the precip area. Will leave mention of mix out of the
forecast due to skepticism about the GFS QPF field.
After a few lingering showers across the far E/SE KILX CWA
Saturday morning, dry and warmer weather will be the rule this
weekend. As southerly winds develop, high temperatures will climb
into the lower to middle 60s by Sunday.
LONG TERM...Monday through Thursday
Models are still advertising cold frontal passage late Monday,
although amount of available moisture appears to be quite limited.
GFS surface dewpoints are initially around 40 degrees Monday
morning and only climb to the upper 40s to near 50 by late
afternoon. Despite decent upper dynamics associated with vigorous
short-wave, lack of deep moisture return from the Gulf will limit
convective potential. As a result, will only carry low chance for
showers on Monday. Slightly cooler and drier weather will settle
into the region behind the departing front on Tuesday before
another system comes into the picture by mid-week. There are still
some key timing differences with this feature: however, all models
agree that it will have much more moisture to work with. With
short-wave crossing the Rockies into the central CONUS, surface
low pressure is expected to track from eastern Colorado on
Tuesday to the southern Great Lakes by Thursday night. Initial
surge of WAA clouds/precip will arrive Tuesday night into
Wednesday: however, with central Illinois remaining in the cool
sector, very little thunder is expected. Once warm front lifts
northward into the area and low pressure approaches from the
southwest, showers and thunderstorms will become more prevalent
Wednesday night into Thursday.
Barnes
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1018 AM CDT FRI MAR 28 2014
.DISCUSSION...
1018 AM CDT
HAVE MADE SOME ADJUSTMENTS TO SKY GRIDS TODAY TO BE A BIT LESS
OPTIMISTIC WITH CLEARING. LOW LEVEL MOISTURE/STRATUS IS CURRENTLY
TRAPPED UNDER A FAIRLY SHARP INVERSION AND INVERSION IS LIKELY TO
PERSIST NOT OFFERING MUCH HOPE FOR BETTER MIXING. CLEARING LINE
OVER CENTRAL WISCONSIN IS MAKING FAIRLY QUICK PROGRESS SOUTHWARD
AND WILL PROBABLY MAKE IT INTO AT LEAST OUR NORTHERN CWA THIS
AFTERNOON...THOUGH WITH LOW LEVEL FLOW SLACKENING THIS AFTERNOON
AND VEERING NE WOULD EXPECT THIS CLEARING LINE TO SLOW DOWN A BIT.
ASSUMING CLOUD COVER LINGERS INTO THE AFTERNOON...TEMPERATURES
WILL BE SLOW TO RECOVER AND HAVE SHAVED A FEW DEGREES OFF GOING
HIGH TEMPS.
UPDATED GRIDS/TEXT PRODUCTS HAVE BEEN SENT.
IZZI
&&
.PREV DISCUSSION...
323 AM CDT
TODAY...
SURFACE COLD FRONT IS CLEARING THE EASTERN COUNTIES IN THE CWA EARLY
THIS MORNING WHILE A SECONDARY TROUGH IS DIGGING ACROSS NORTHERN
ILLINOIS WITH WINDS TURNING SHARPLY TO THE NNW WITH GUSTS WELL INTO
THE 20 KT RANGE. SHOWERS BEHIND THIS TROUGH WILL SWEEP ACROSS
NORTHERN ILLINOIS AND NORTHWEST INDIANA...EXITING TO THE EAST BY MID
TO LATE MORNING. BREEZY CONDITIONS THIS MORNING SHOULD GRADUALLY
TAPER THROUGH THE DAY AS THE AS THE LOW LIFTS TOWARDS QUEBEC AND
FILLS. TEMPS INTO THE MID TO UPPER 40S ARE EXPECTED THIS
AFTERNOON...BUT A LAKE BREEZE WILL TURN WINDS NORTHEASTERLY AND COOL
TEMPS BACK INTO THE 30S ALONG THE LAKE.
THIS WEEKEND...
LOW PRESSURE WILL LIFT FROM ARKLATEX INTO THE UPPER OHIO VALLEY BY
MIDDAY SATURDAY. BEST CHANCES FOR PRECIP WILL BE SOUTH OF I-80
ESPECIALLY IN NORTHWEST INDIANA...AND FOR NOW IT APPEARS AREAS NORTH
WILL REMAIN DRY. GFS INDICATES WET BULBS DROPPING BELOW ZERO THROUGH
THE COLUMN AROUND OR BEFORE THE ONSET OF PRECIP INDICATE ALL SNOW.
NAM SOUNDINGS ON THE OTHER HAND SHOW SLIGHTLY WARMER TEMPS ALOFT
HINTING AT THE POSSIBILITY FOR RAIN/SNOW MIX...THOUGH SREF P-TYPE
PROBABILITY INDICATES BETTER CHANCES FOR SNOW. COMING OFF HIGHS IN
THE UPPER 40S IN AREAS MOST LIKELY TO SEE PRECIP...AND OVERNIGHT
LOWS SOUTH OF 80 AT OR EVEN SLIGHTLY ABOVE FREEZING...THE LIKELIHOOD
OF ACCUMULATING SNOW IS LOW AND WOULD LIKELY BE CONFINED TO THE
GRASS. IN ADDITION...GIVEN THE MARGINAL SOUNDINGS...SNOW PRODUCTION
WOULD BE INEFFICIENT. WILL MAINTAIN RAIN/SNOW MIX IN THE FORECAST
FOR NOW GIVEN THE CURRENT UNCERTAINTY.
HIGH PRESSURE WILL THEN TRANSLATE ACROSS THE REGION OVER THE
REMAINDER OF THE WEEKEND RESULTING IN DRY WEATHER FROM SATURDAY
AFTERNOON ON. H85 THERMAL TROUGH WILL APPROACH THE REGION ON
SATURDAY...THOUGH SUBSIDENCE ALOFT SETTLING OVER THE UPPER MIDWEST
THROUGH THE DAY SATURDAY WILL RESULT IN DRYING AND WARMING OF THE
MID LEVELS WHICH WILL HELP MODULATE THE COLDER AIRMASS MOVING
OVERHEAD. WITH AFTERNOON SUNSHINE...EXPECT AREAS AWAY FROM THE LAKE
TO RISE INTO THE MID TO UPPER 40S AGAIN...WITH A FEW 50S MAINLY
SOUTH OF I-80. ALONG THE LAKE FRONT...A BREEZE OFF THE LAKE THROUGH
THE DAY WILL KEEP TEMPERATURES MUCH COOLER...IN THE MID 30S. THE
SURFACE RIDGE AXIS WILL PASS OVERHEAD SATURDAY NIGHT...AND SOUTHERLY
FLOW WILL RAMP UP THROUGH THE DAY SUNDAY AHEAD OF OUR NEXT AREA OF
LOW PRESSURE STARTING TO TAKE SHAPE OVER THE PLAINS. STRONG WARM
ADVECTION IS EXPECTED THROUGH THE DAY SUNDAY WHICH WILL RESULT IN
H85 TEMPS RISING TO AROUND 10C BY SUNDAY EVENING. SOUTHERLY WINDS
MAY TAKE ON A SLIGHT WESTERLY COMPONENT BY SUNDAY AFTERNOON...IN THE
190-200 DIRECTION...WHICH WITH THE INCREASING WINDS SHOULD HELP
STAVE OFF ANY LAKE BREEZE/LAKE COOLING SUNDAY. NAM/GFS SOUNDINGS
SHOW LOW TO MID 20 KT GUSTS POSSIBLE BY SUNDAY AFTERNOON.
TEMPERATURES SHOULD RISE TO AROUND 60 RIGHT UP TO THE LAKE FRONT
SUNDAY AFTERNOON.
MONDAY...
AFOREMENTIONED SURFACE LOW PROGGED TO LIFT FROM THE MID MISSOURI
VALLEY EARLY MONDAY INTO MN/WI MONDAY EVENING. LATEST GUIDANCE IN
DECENT AGREEMENT ON THE LOCAL AREA GETTING FULL WARM SECTOR ON
MONDAY. LEANED TOWARD WARMER SIDE OF GUIDANCE MONDAY WITH A BLEND OF
BIAS CORRECTED GEM AND ECMWF. THIS RESULTS IN LOW TO MID 60S AREA
WIDE MONDAY AFTERNOON...AND WITH A MODERATE-STRONG SSW WIND...DO NOT
ANTICIPATE ANY COOLING ALONG THE LAKE. A 60-70KT LOW LEVEL JET
FOCUSES STRONG CONVERGENCE ACROSS THE MID MISSOURI VALLEY SUNDAY
NIGHT...THEN AT 40-50 KT REFOCUSES TO OUR NORTH MONDAY
EVENING/NIGHT. ACROSS NORTHERN ILLINOIS IN THE WARM SECTOR...
INSTABILITY IS PRETTY MEAGER WITH A STRONG CAP IN PLACE...THOUGH
SOME DYNAMIC COOLING ASSOCIATED WITH NEGATIVELY TILTED H5 WAVE AND
EXIT REGION OF UPPER JET MAY RESULT IN SOME SCATTERED CONVECTION.
ALL-IN-ALL THOUGH...GIVEN THE UNFAVORABLE TIMING OF THE FRONT
OVERNIGHT...NOT TOO IMPRESSED WITH PRECIP CHANCES MONDAY AND TRIMMED
POPS FOR THIS PERIOD.
TUESDAY THROUGH THURSDAY...
PRETTY LOW CONFIDENCE IN THE DETAILS AT THIS POINT...BUT TUESDAY
THROUGH THURSDAY SHOULD BE AN ACTIVE PERIOD WITH A SERIES OF
DISTURBANCES MOVING ACROSS THE REGION. THERE REMAINS SIGNIFICANT
DIFFERENCES AT THIS POINT BETWEEN MODELS WITH RESPECT TO THE LOW
TRACK WHICH WILL DETERMINE TEMPS AND PRECIP TYPE. GFS INDICATES A
FASTER MORE SOUTHERLY LOW WHILE THE ECMWF HINTS AT A WARMER SOLUTION
WITH A DEEPER LOW THAT TRACKS FARTHER NORTH. FOR NOW...STAYED CLOSE
TO A CONSENSUS BLEND.
TUBELESS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* NORTHWEST WINDS TURNING NORTH TOWARD MIDDAY AND NORTHEAST THIS
AFTERNOON.
* MVFR CIGS AROUND 015 GRADUALLY LIFTING TOWARD 020-025 INTO THE
AFTERNOON.
MDB
//DISCUSSION...UPDATED 14Z...
PRECIP HAS CLEARED THE TERMINALS LEAVING AN EXPANSIVE AREA OF MVFR
CLOUD COVER IN THE 012-020 RANGE WHICH WILL LIKELY CONTINUE INTO
THE AFTERNOON...THOUGH MAY SEE SCATTERING DEVELOP ON ITS FRINGES
INTO MIDDAY. OTHERWISE NORTHWEST WINDS WILL TURN NORTHERLY INTO
MIDDAY THEN NORTHEAST THIS AFTERNOON.
MDB
FROM 12Z...
RAIN SHOWERS WITH POCKETS OF IFR WRAPPING AROUND THE BACK SIDE OF
A DEPARTING LOW WILL CLEAR THE AREA BY MID MORNING. WINDS HAVE
TURNED NORTHWEST AND WILL CONTINUE TO VEER AROUND TO NORTHEAST BY
THE AFTERNOON. NOT CERTAIN ABOUT TIMING OF CHANGE OVER TO AN
EASTERLY COMPONENT BUT BEST ESTIMATE IS AROUND NOON OR SHORTLY
AFTER. LINGERING MVFR CIGS LATE THIS MORNING WILL EVENTUALLY
SCATTER OUT TO VFR THIS AFTERNOON.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* HIGH CONFIDENCE IN WIND TRENDS...MEDIUM CONFIDENCE IN TIMING OF
DIRECTION CHANGES.
* HIGH CONFIDENCE IN MVFR CIGS THROUGH EARLY AFTERNOON...WITH
MEDIUM CONFIDENCE IN HOW LONG THEY CONTINUE THROUGH THE
AFTERNOON.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...VFR. NORTHEAST WINDS TURNING SOUTHEAST.
SUNDAY...VFR. SOUTH WINDS.
MONDAY...CHANCE OF SHRA/TSRA LATE. MODERATE-STRONG SOUTH WINDS.
TUESDAY...VFR PROBABLE. WEST WINDS.
WEDNESDAY...CHANCE OF RAIN AND IFR/MVFR CIGS. NORTHEAST WINDS.
THURSDAY...CHANCE OF RAIN OR SNOW AND IFR/MVFR. NORTHEAST WINDS.
LENNING
&&
.MARINE...
307 AM CDT
A STRONG LOW PRESSURE SYSTEM IS EXITING THE AREA THIS MORNING
ACROSS LOWER MICHIGAN AND LAKE HURON. NORTHWEST TO NORTH GALES
WILL EASE QUICKLY THIS MORNING AS THE LOW PULLS AWAY AND THE
PRESSURE GRADIENT WEAKENS. A RIDGE WILL CROSS THE LAKE ON SATURDAY
BEFORE THE NEXT LOW PRESSURE SYSTEM STARTS TO APPROACH OUT OF THE
CENTRAL PLAINS. ALTHOUGH THIS LOW DOES NOT REACH THE LAKE UNTIL
TUESDAY...SOUTHERLY FLOW AHEAD OF THIS SYSTEM WILL DEVELOP BY
EARLY SUNDAY. A PERIOD OF GALES IS AGAIN POSSIBLE LATE MONDAY
INTO TUESDAY...ESPECIALLY ACROSS THE SOUTHERN HALF OF THE
LAKE...AS THE LOW MOVES THROUGH.
LENNING
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 2 PM FRIDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
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Area Forecast Discussion
National Weather Service Lincoln IL
1014 AM CDT Fri Mar 28 2014
.DISCUSSION...
ISSUED 1014 AM CDT Fri Mar 28 2014
Updated forecast to lower highs a few degrees and increase cloud
cover mainly across central/northern CWA. 10 AM visible satellite
imagery showed a strip of clearing north of the Ohio River
extending into the far SE CWA, while farther north a thick blanket
of stratus/SC stretched back through most of MO/IA and southern
WI. HRRR and RAP RH trends in the 950-900 MB level suggest the
clearing over the far SE will slowly shift north towards I-72 by
late afternoon as southerly winds strengthen in that layer. This
clearing will be brief however as mid clouds ahead of next wave
developing in the Plains overspread the region later this
afternoon and evening. Brisk NW winds this morning to ease through
afternoon as low pressure pushes east of the Great Lakes and MSLP
gradient relaxes.
25
&&
.AVIATION...
ISSUED 646 AM CDT Fri Mar 28 2014
MVFR cigs will continue this morning. Big question is how long
will these clouds last. This time of year, clouds at this level
usually burn off rather quickly. However, area is in good cyclonic
flow will lots of clouds/low level moisture across most of MO, all
of Iowa and up into WI. So, think that these clouds will last
longer than normal. So have the MVFR cigs continuing until around
18z, and then lower clouds will scatter out; but high cirrus
around 20kft will have moved in by then. As the next system
approaches the area, but moves south of the state, clouds will
begin to lower during the early evening hours, after 00z, to
around 8kft. Believe rain is possible at DEC and CMI TAFs during
the overnight hours, so have included 5sm -ra with cigs just above
the 3kft foot level. Other sites will not see rain, but see cigs
fall to around 4-5kft late. West winds will remain gusty for a few
hours this morning and then decrease for later this morning, with
CMI being the last one to loose the gusts. As wind speeds
decrease, direction will also become more northerly. Then
northeast winds are expected tomorrow night.
Auten
&&
.PREV DISCUSSION...
ISSUED 313 AM CDT Fri Mar 28 2014
SHORT TERM...Today through Sunday
Main forecast challenge in the immediate short-term will be timing
the departure of low clouds today. 07z/2am surface analysis shows
low pressure over southern Lake Michigan with cold front trailing
southward along the I-57 corridor. Extensive area of wrap-around
cloud cover is noted on IR satellite imagery blanketing Iowa,
northern Missouri, and western Illinois. With low-level flow
becoming northwesterly, these clouds will spill across central
Illinois early this morning. All model guidance suggests an
overcast start to the day, but how quickly the clouds clear out
remains in question. NAM forecast soundings indicate clouds will
mix out/dissipate between 15z and 18z. Latest HRRR hints at this
as well, although the process may be slower than the NAM
advertises. Given subsidence behind departing upper short-wave and
late March sun working on the low clouds, think skies will
temporarily clear around midday into the early afternoon. After
that, high clouds will quickly begin to increase ahead of the next
approaching system by mid to late afternoon.
Next forecast concern revolves around low pressure expected to
track from Texas into the Tennessee River Valley tonight. Models
have been having difficulty resolving how far north associated
precip will spread. 00z Mar 28 suite is still in disagreement,
with the GFS being the most aggressive in bringing precip furthest
north. Since GFS is often too bullish with light QPF events and
airmass will be drying today, think the NAM has a more realistic
handle on the situation. As such, will keep locations along and
north of a Jacksonville to Bloomington line dry tonight. Best rain
chances will be focused along/south of I-70 in closer proximity to
the low track, with POPs steadily decreasing further northwest.
Despite overnight lows in the middle to upper 30s, NAM forecast
soundings remain warm enough for rain. If colder/further north GFS
verifies, a rain/snow mix may be possible along the northern
fringe of the precip area. Will leave mention of mix out of the
forecast due to skepticism about the GFS QPF field.
After a few lingering showers across the far E/SE KILX CWA
Saturday morning, dry and warmer weather will be the rule this
weekend. As southerly winds develop, high temperatures will climb
into the lower to middle 60s by Sunday.
LONG TERM...Monday through Thursday
Models are still advertising cold frontal passage late Monday,
although amount of available moisture appears to be quite limited.
GFS surface dewpoints are initially around 40 degrees Monday
morning and only climb to the upper 40s to near 50 by late
afternoon. Despite decent upper dynamics associated with vigorous
short-wave, lack of deep moisture return from the Gulf will limit
convective potential. As a result, will only carry low chance for
showers on Monday. Slightly cooler and drier weather will settle
into the region behind the departing front on Tuesday before
another system comes into the picture by mid-week. There are still
some key timing differences with this feature: however, all models
agree that it will have much more moisture to work with. With
short-wave crossing the Rockies into the central CONUS, surface
low pressure is expected to track from eastern Colorado on
Tuesday to the southern Great Lakes by Thursday night. Initial
surge of WAA clouds/precip will arrive Tuesday night into
Wednesday: however, with central Illinois remaining in the cool
sector, very little thunder is expected. Once warm front lifts
northward into the area and low pressure approaches from the
southwest, showers and thunderstorms will become more prevalent
Wednesday night into Thursday.
Barnes
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
702 AM CDT FRI MAR 28 2014
.DISCUSSION...
323 AM CDT
TODAY...
SURFACE COLD FRONT IS CLEARING THE EASTERN COUNTIES IN THE CWA EARLY
THIS MORNING WHILE A SECONDARY TROUGH IS DIGGING ACROSS NORTHERN
ILLINOIS WITH WINDS TURNING SHARPLY TO THE NNW WITH GUSTS WELL INTO
THE 20 KT RANGE. SHOWERS BEHIND THIS TROUGH WILL SWEEP ACROSS
NORTHERN ILLINOIS AND NORTHWEST INDIANA...EXITING TO THE EAST BY MID
TO LATE MORNING. BREEZY CONDITIONS THIS MORNING SHOULD GRADUALLY
TAPER THROUGH THE DAY AS THE AS THE LOW LIFTS TOWARDS QUEBEC AND
FILLS. TEMPS INTO THE MID TO UPPER 40S ARE EXPECTED THIS
AFTERNOON...BUT A LAKE BREEZE WILL TURN WINDS NORTHEASTERLY AND COOL
TEMPS BACK INTO THE 30S ALONG THE LAKE.
THIS WEEKEND...
LOW PRESSURE WILL LIFT FROM ARKLATEX INTO THE UPPER OHIO VALLEY BY
MIDDAY SATURDAY. BEST CHANCES FOR PRECIP WILL BE SOUTH OF I-80
ESPECIALLY IN NORTHWEST INDIANA...AND FOR NOW IT APPEARS AREAS NORTH
WILL REMAIN DRY. GFS INDICATES WET BULBS DROPPING BELOW ZERO THROUGH
THE COLUMN AROUND OR BEFORE THE ONSET OF PRECIP INDICATE ALL SNOW.
NAM SOUNDINGS ON THE OTHER HAND SHOW SLIGHTLY WARMER TEMPS ALOFT
HINTING AT THE POSSIBILITY FOR RAIN/SNOW MIX...THOUGH SREF P-TYPE
PROBABILITY INDICATES BETTER CHANCES FOR SNOW. COMING OFF HIGHS IN
THE UPPER 40S IN AREAS MOST LIKELY TO SEE PRECIP...AND OVERNIGHT
LOWS SOUTH OF 80 AT OR EVEN SLIGHTLY ABOVE FREEZING...THE LIKELIHOOD
OF ACCUMULATING SNOW IS LOW AND WOULD LIKELY BE CONFINED TO THE
GRASS. IN ADDITION...GIVEN THE MARGINAL SOUNDINGS...SNOW PRODUCTION
WOULD BE INEFFICIENT. WILL MAINTAIN RAIN/SNOW MIX IN THE FORECAST
FOR NOW GIVEN THE CURRENT UNCERTAINTY.
HIGH PRESSURE WILL THEN TRANSLATE ACROSS THE REGION OVER THE
REMAINDER OF THE WEEKEND RESULTING IN DRY WEATHER FROM SATURDAY
AFTERNOON ON. H85 THERMAL TROUGH WILL APPROACH THE REGION ON
SATURDAY...THOUGH SUBSIDENCE ALOFT SETTLING OVER THE UPPER MIDWEST
THROUGH THE DAY SATURDAY WILL RESULT IN DRYING AND WARMING OF THE
MIDLEVELS WHICH WILL HELP MODULATE THE COLDER AIRMASS MOVING
OVERHEAD. WITH AFTERNOON SUNSHINE...EXPECT AREAS AWAY FROM THE LAKE
TO RISE INTO THE MID TO UPPER 40S AGAIN...WITH A FEW 50S MAINLY
SOUTH OF I-80. ALONG THE LAKE FRONT...A BREEZE OFF THE LAKE THROUGH
THE DAY WILL KEEP TEMPERATURES MUCH COOLER...IN THE MID 30S. THE
SURFACE RIDGE AXIS WILL PASS OVERHEAD SATURDAY NIGHT...AND SOUTHERLY
FLOW WILL RAMP UP THROUGH THE DAY SUNDAY AHEAD OF OUR NEXT AREA OF
LOW PRESSURE STARTING TO TAKE SHAPE OVER THE PLAINS. STRONG WARM
ADVECTION IS EXPECTED THROUGH THE DAY SUNDAY WHICH WILL RESULT IN
H85 TEMPS RISING TO AROUND 10C BY SUNDAY EVENING. SOUTHERLY WINDS
MAY TAKE ON A SLIGHT WESTERLY COMPONENT BY SUNDAY AFTERNOON...IN THE
190-200 DIRECTION...WHICH WITH THE INCREASING WINDS SHOULD HELP
STAVE OFF ANY LAKE BREEZE/LAKE COOLING SUNDAY. NAM/GFS SOUNDINGS
SHOW LOW TO MID 20 KT GUSTS POSSIBLE BY SUNDAY AFTERNOON.
TEMPERATURES SHOULD RISE TO AROUND 60 RIGHT UP TO THE LAKE FRONT
SUNDAY AFTERNOON.
MONDAY...
AFOREMENTIONED SURFACE LOW PROGGED TO LIFT FROM THE MID MISSOURI
VALLEY EARLY MONDAY INTO MN/WI MONDAY EVENING. LATEST GUIDANCE IN
DECENT AGREEMENT ON THE LOCAL AREA GETTING FULL WARM SECTOR ON
MONDAY. LEANED TOWARD WARMER SIDE OF GUIDANCE MONDAY WITH A BLEND OF
BIAS CORRECTED GEM AND ECMWF. THIS RESULTS IN LOW TO MID 60S AREA
WIDE MONDAY AFTERNOON...AND WITH A MODERATE-STRONG SSW WIND...DO NOT
ANTICIPATE ANY COOLING ALONG THE LAKE. A 60-70KT LOW LEVEL JET
FOCUSES STRONG CONVERGENCE ACROSS THE MID MISSOURI VALLEY SUNDAY
NIGHT...THEN AT 40-50 KT REFOCUSES TO OUR NORTH MONDAY
EVENING/NIGHT. ACROSS NORTHERN ILLINOIS IN THE WARM SECTOR...
INSTABILITY IS PRETTY MEAGER WITH A STRONG CAP IN PLACE...THOUGH
SOME DYNAMIC COOLING ASSOCIATED WITH NEGATIVELY TILTED H5 WAVE AND
EXIT REGION OF UPPER JET MAY RESULT IN SOME SCATTERED CONVECTION.
ALL-IN-ALL THOUGH...GIVEN THE UNFAVORABLE TIMING OF THE FRONT
OVERNIGHT...NOT TOO IMPRESSED WITH PRECIP CHANCES MONDAY AND TRIMMED
POPS FOR THIS PERIOD.
TUESDAY THROUGH THURSDAY...
PRETTY LOW CONFIDENCE IN THE DETAILS AT THIS POINT...BUT TUESDAY
THROUGH THURSDAY SHOULD BE AN ACTIVE PERIOD WITH A SERIES OF
DISTURBANCES MOVING ACROSS THE REGION. THERE REMAINS SIGNIFICANT
DIFFERENCES AT THIS POINT BETWEEN MODELS WITH RESPECT TO THE LOW
TRACK WHICH WILL DETERMINE TEMPS AND PRECIP TYPE. GFS INDICATES A
FASTER MORE SOUTHERLY LOW WHILE THE ECMWF HINTS AT A WARMER SOLUTION
WITH A DEEPER LOW THAT TRACKS FARTHER NORTH. FOR NOW...STAYED CLOSE
TO A CONSENSUS BLEND.
DEUBELBEISS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* PERIODS OF IFR CIGS WITH RAIN SHOWERS EARLY THIS MORNING...THEN
MVFR INTO AFTERNOON.
* NORTHWEST WINDS GUSTY AT TIMES...TURNING NORTH BY MIDDAY AND NORTHEAST
BY AFTERNOON.
LENNING
//DISCUSSION...UPDATED 12Z...
RAIN SHOWERS WITH POCKETS OF IFR WRAPPING AROUND THE BACK SIDE OF
A DEPARTING LOW WILL CLEAR THE AREA BY MID MORNING. WINDS HAVE
TURNED NORTHWEST AND WILL CONTINUE TO VEER AROUND TO NORTHEAST BY
THE AFTERNOON. NOT CERTAIN ABOUT TIMING OF CHANGE OVER TO AN
EASTERLY COMPONENT BUT BEST ESTIMATE IS AROUND NOON OR SHORTLY
AFTER. LINGERING MVFR CIGS LATE THIS MORNING WILL EVENTUALLY
SCATTER OUT TO VFR THIS AFTERNOON.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* MEDIUM CONFIDENCE ON TIMING AND DURATION OF IFR EARLY THIS
MORNING...BUT HIGHER CONFIDENCE OF PREVAILING MVFR LATER.
* HIGH CONFIDENCE THAT RAIN SHOWERS WILL END BY MID MORNING.
* MEDIUM CONFIDENCE ON TIMING OF WIND DIRECTION CHANGES.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...VFR. NORTHEAST WINDS TURNING SOUTHEAST.
SUNDAY...VFR. SOUTH WINDS.
MONDAY...CHANCE OF SHRA/TSRA LATE. MODERATE-STRONG SOUTH WINDS.
TUESDAY...VFR PROBABLE. WEST WINDS.
WEDNESDAY...CHANCE OF RAIN AND IFR/MVFR CIGS. NORTHEAST WINDS.
THURSDAY...CHANCE OF RAIN OR SNOW AND IFR/MVFR. NORTHEAST WINDS.
LENNING
&&
.MARINE...
307 AM CDT
A STRONG LOW PRESSURE SYSTEM IS EXITING THE AREA THIS MORNING
ACROSS LOWER MICHIGAN AND LAKE HURON. NORTHWEST TO NORTH GALES
WILL EASE QUICKLY THIS MORNING AS THE LOW PULLS AWAY AND THE
PRESSURE GRADIENT WEAKENS. A RIDGE WILL CROSS THE LAKE ON SATURDAY
BEFORE THE NEXT LOW PRESSURE SYSTEM STARTS TO APPROACH OUT OF THE
CENTRAL PLAINS. ALTHOUGH THIS LOW DOES NOT REACH THE LAKE UNTIL
TUESDAY...SOUTHERLY FLOW AHEAD OF THIS SYSTEM WILL DEVELOP BY
EARLY SUNDAY. A PERIOD OF GALES IS AGAIN POSSIBLE LATE MONDAY
INTO TUESDAY...ESPECIALLY ACROSS THE SOUTHERN HALF OF THE
LAKE...AS THE LOW MOVES THROUGH.
LENNING
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 AM FRIDAY.
SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 11 AM FRIDAY.
SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 2 PM FRIDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
646 AM CDT Fri Mar 28 2014
.DISCUSSION...
ISSUED 313 AM CDT Fri Mar 28 2014
SHORT TERM...Today through Sunday
Main forecast challenge in the immediate short-term will be timing
the departure of low clouds today. 07z/2am surface analysis shows
low pressure over southern Lake Michigan with cold front trailing
southward along the I-57 corridor. Extensive area of wrap-around
cloud cover is noted on IR satellite imagery blanketing Iowa,
northern Missouri, and western Illinois. With low-level flow
becoming northwesterly, these clouds will spill across central
Illinois early this morning. All model guidance suggests an
overcast start to the day, but how quickly the clouds clear out
remains in question. NAM forecast soundings indicate clouds will
mix out/dissipate between 15z and 18z. Latest HRRR hints at this
as well, although the process may be slower than the NAM
advertises. Given subsidence behind departing upper short-wave and
late March sun working on the low clouds, think skies will
temporarily clear around midday into the early afternoon. After
that, high clouds will quickly begin to increase ahead of the next
approaching system by mid to late afternoon.
Next forecast concern revolves around low pressure expected to
track from Texas into the Tennessee River Valley tonight. Models
have been having difficulty resolving how far north associated
precip will spread. 00z Mar 28 suite is still in disagreement,
with the GFS being the most aggressive in bringing precip furthest
north. Since GFS is often too bullish with light QPF events and
airmass will be drying today, think the NAM has a more realistic
handle on the situation. As such, will keep locations along and
north of a Jacksonville to Bloomington line dry tonight. Best rain
chances will be focused along/south of I-70 in closer proximity to
the low track, with POPs steadily decreasing further northwest.
Despite overnight lows in the middle to upper 30s, NAM forecast
soundings remain warm enough for rain. If colder/further north GFS
verifies, a rain/snow mix may be possible along the northern
fringe of the precip area. Will leave mention of mix out of the
forecast due to skepticism about the GFS QPF field.
After a few lingering showers across the far E/SE KILX CWA
Saturday morning, dry and warmer weather will be the rule this
weekend. As southerly winds develop, high temperatures will climb
into the lower to middle 60s by Sunday.
LONG TERM...Monday through Thursday
Models are still advertising cold frontal passage late Monday,
although amount of available moisture appears to be quite limited.
GFS surface dewpoints are initially around 40 degrees Monday
morning and only climb to the upper 40s to near 50 by late
afternoon. Despite decent upper dynamics associated with vigorous
short-wave, lack of deep moisture return from the Gulf will limit
convective potential. As a result, will only carry low chance for
showers on Monday. Slightly cooler and drier weather will settle
into the region behind the departing front on Tuesday before
another system comes into the picture by mid-week. There are still
some key timing differences with this feature: however, all models
agree that it will have much more moisture to work with. With
short-wave crossing the Rockies into the central CONUS, surface
low pressure is expected to track from eastern Colorado on
Tuesday to the southern Great Lakes by Thursday night. Initial
surge of WAA clouds/precip will arrive Tuesday night into
Wednesday: however, with central Illinois remaining in the cool
sector, very little thunder is expected. Once warm front lifts
northward into the area and low pressure approaches from the
southwest, showers and thunderstorms will become more prevalent
Wednesday night into Thursday.
Barnes
&&
.AVIATION...
ISSUED 646 AM CDT Fri Mar 28 2014
MVFR cigs will continue this morning. Big question is how long
will these clouds last. This time of year, clouds at this level
usually burn off rather quickly. However, area is in good cyclonic
flow will lots of clouds/low level moisture across most of MO, all
of Iowa and up into WI. So, think that these clouds will last
longer than normal. So have the MVFR cigs continuing until around
18z, and then lower clouds will scatter out; but high cirrus
around 20kft will have moved in by then. As the next system
approaches the area, but moves south of the state, clouds will
begin to lower during the early evening hours, after 00z, to
around 8kft. Believe rain is possible at DEC and CMI TAFs during
the overnight hours, so have included 5sm -ra with cigs just above
the 3kft foot level. Other sites will not see rain, but see cigs
fall to around 4-5kft late. West winds will remain gusty for a few
hours this morning and then decrease for later this morning, with
CMI being the last one to loose the gusts. As wind speeds
decrease, direction will also become more northerly. Then
northeast winds are expected tomorrow night.
Auten
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
315 AM CDT FRI MAR 28 2014
.DISCUSSION...
801 PM CDT
ONLY SOME MINOR TWEAKS HAVE BEEN MADE TO THE GOING FORECAST FOR
THE REST OF TONIGHT INTO EARLY FRIDAY MORNING. THE PRIMARY TIME
FOR RAIN SHOWERS WITH SOME SCATTERED THUNDERSTORMS REMAINS NOW
THROUGH MIDNIGHT.
A WELL-DEFINED SHORT-WAVE TROUGH FROM MN INTO CENTRAL MN THIS
EARLY EVE IS ADVANCING EAST NORTHEASTWARD. THE 00Z RAOB SOUNDINGS AND
PROFILERS INDICATED A 55-60 KT LOW LEVEL JET AHEAD OF THIS INTO
THE FORECAST AREA. SOME OF THE BETTER DEEPER MOISTURE RETURN THAT
COULD BE ASSOCIATED WITH THIS IS LIKELY BEING ROBBED BY QUITE A
BIT OF CONVECTION ACROSS THE LOWER MISSISSIPPI VALLEY...AS WELL
AS THE SUBTROPICAL JET REMAINING WELL SOUTH.
NONETHELESS...NORTH-TO-SOUTH ARCS OF CONVECTION AHEAD OF THE MAIN
VORT MAX CONTINUE TO PROGRESS ACROSS NORTHERN AND WESTERN IL AND
SHOULD CONTINUE AT A SIMILAR COVERAGE INTO THE CHICAGO AREA. THE
DEGREE OF LIGHTNING HAS FLUCTUATED SOME BUT CONFINED TO WITHIN A
NARROW AXIS OF DWINDLING MUCAPE AHEAD OF THE SYSTEM. SOME BRIEF
DOWNPOURS AND MAYBE A FEW BOOSTS TO THE ALREADY HIGH SYNOPTIC
GUSTS...BUT ALL-IN-ALL JUST SOME GARDEN VARIETY SCATTERED STORMS
AS EXPECTED. AS A DRY CONVEYOR BELT AS SEEN ON WATER VAPOR AND
UPPER AIR RAOBS IN KS ROTATES INTO THE FORECAST AREA EARLY
OVERNIGHT THERE SHOULD STILL BE A LULL IN ACTIVITY...WITH SOME
UPTICK EXPECTED BETWEEN 3-8 AM NORTH OF I-80 AS THE CENTER OF THE
WAVE PASSES AND TAPS SOME WRAPAROUND MOISTURE. IF THE LOW-LEVELS
COOL ENOUGH...SOME WET SNOW IS POSSIBLE INTO THE EARLY PART OF THE
MORNING RUSH. WITH SURFACE TEMPS SEVERAL DEGREES ABOVE FREEZING
AND ROADS ALREADY WET...WOULD NOT SEEM LIKE MUCH FOR IMPACTS.
TEMPERATURES WILL CONTINUE TO HOLD STEADY IN THE STRONG SOUTHERLY
FLOW WITH ADVECTION AND HIGHER DEW POINT AIR HELPING TO MAINTAIN
TEMPERATURES IN THE UPPER 40S TO MID 50S FAR SOUTH. AS THE FRONT
PASSES DURING THE EARLY OVERNIGHT...READINGS SHOULD STEADILY HEAD
DOWNWARD WITH GOING FORECAST HOURLY TEMPS AND LOWS LOOKING ON
TRACK.
MTF
//PREV DISCUSSION...
300 PM...FORECAST CONCERNS INCLUDE THUNDERSTORM POTENTIAL THIS
EVENING...MIX OF RAIN/SNOW EARLY FRIDAY MORNING...LAKE BREEZES
FRIDAY AND SATURDAY...CHANCE OF RAIN/SNOW FRIDAY NIGHT SOUTH...
TEMPS AROUND 60 SUNDAY/MONDAY AND ANOTHER CHANCE OF THUNDERSTORMS
MONDAY AFTERNOON/EVENING.
TEMPS HAVE STRUGGLED INTO THE LOWER/MID 40S THIS AFTERNOON WITH
BREEZY SOUTHERLY WINDS...WHICH HAVE BEEN LOWER THAN EXPECTED.
CURRENT SHOWER ACTIVITY WILL MOVE NORTHEAST OF THE CWA IN THE NEXT
1-2 HOURS WITH A 2-4 HOUR DRY PERIOD INTO EARLY THIS EVENING. LOW
PRESSURE OVER SOUTHWEST IOWA WILL LIFT NORTHEAST ACROSS SOUTHERN
WISCONSIN THIS EVENING WITH A TRAILING COLD FRONT MOVING ACROSS
THE AREA THIS EVENING. LINE OF THUNDERSTORMS HAS DEVELOPED AHEAD
OF THIS COLD FRONT ACROSS EASTERN KANSAS AND WESTERN MISSOURI.
THIS ACTIVITY WILL ACCOMPANY THE FRONT THIS EVENING THOUGH SHORT
TERM/HIGH RES GUIDANCE DIFFERS ON THUNDER COVERAGE/INTENSITY
LATER THIS EVENING. POSSIBLE THAT SOME OF THIS WILL LIFT NORTH
WITH THE LOW AND THE MAIN LINE MOVES EAST ACROSS CENTRAL IL. THUS
HAVE MAINTAINED CHANCE THUNDER MENTION WHICH MAY NEED TO BE
INCREASED AS THE LINE APPROACHES. THUNDER POTENTIAL/DURATION WILL
ONLY LAST AN HOUR OR TWO. PRECIP EXPECTED TO END BEHIND THE FRONT
BUT THEN WRAP AROUND PRECIP ON THE BACK SIDE OF THE LOW WILL
SPREAD BACK ACROSS NORTHERN ILLINOIS OVERNIGHT PERHAPS LINGERING
INTO EARLY FRIDAY MORNING. AS COLDER AIR SPREADS BACK ACROSS THE
REGION...PRECIP WILL CHANGE TO A MIX OF RAIN/SNOW WITH PERHAPS
PRECIP BECOMING ALL SNOW BEFORE ENDING ACROSS THE FAR NORTH. WHILE
NO ACCUMULATION IS IN THE FORECAST...IF PRECIP WERE TO CHANGE OVER
TO SNOW SOONER...THEN ITS POSSIBLE THERE COULD BE SOME MINOR SNOW
ACCUMULATIONS...AGAIN MAINLY ACROSS THE FAR NORTHERN CWA.
TEMPERATURES WILL CONTINUE TO CLIMB THIS AFTERNOON INTO THIS
EVENING WITH CALENDAR DAY HIGHS LIKELY TO OCCUR IN THE MID/LATE
EVENING AHEAD OF THE FRONT. NOT OUT OF THE QUESTION FOR SOME LOWER
50S TO MAKE IT AS FAR NORTH AS THE CHICAGO METRO AREA WITH STRONG
SOUTHERLY FLOW...BUT THESE TEMPS WILL BE SHORT-LIVED. AS NOTED...
WINDS HAVE NOT BEEN AS STRONG AS ORIGINALLY EXPECTED. HOWEVER...
AS THE LOW APPROACHES AND ONGOING SHOWER ACTIVITY ENDS...EXPECT
WINDS/GUSTS TO INCREASE THROUGH THE LATE AFTERNOON AND INTO THE
EVENING WITH GUSTS UP TO 40 MPH STILL POSSIBLE...PERHAPS A BIT
STRONGER JUST AHEAD AND JUST BEHIND THE FRONT.
ONCE THE PRECIP ENDS FRIDAY MORNING...NORTHERLY WINDS WILL TURN
MORE NORTHEAST AS HIGH PRESSURE BUILDS ACROSS THE UPPER MIDWEST.
GUIDANCE SUGGESTS A RATHER STRONG LAKE BREEZE/FRONT MOVING IN FROM
THE LAKE IN THE AFTERNOON AND HAVE ATTEMPTED TO ACCOUNT FOR THAT
WITH FALLING TEMPS IN THE AFTERNOON AS WINDS SHIFT NORTHEAST.
AHEAD OF THAT LAKE BREEZE...HIGHS IN THE LOWER/MID 40S LOOK ON
TRACK WITH UPPER 40S/NEAR 50 FURTHER INLAND...WESTERN/SOUTHERN CWA.
NOT MUCH CONFIDENCE REGARDING THE NEXT SYSTEM MOVING THROUGH THE
OHIO VALLEY FRIDAY NIGHT INTO SATURDAY MORNING. MODELS HAVE
TRENDED A BIT FURTHER SOUTHEAST AND PRECIP COULD END UP STAYING
MAINLY SOUTH OF THE AREA. ONLY CHANGE TO THIS TIME PERIOD WAS TO
SHIFT THE PRECIP EDGE A BIT FURTHER SOUTH TO THE I-80 CORRIDOR.
PRECIP TYPE ALSO REMAINS PROBLEMATIC...ASSUMING IT PRECIPITATES
THIS FAR NORTH WITH THE POTENTIAL FOR SOME FREEZING RAIN IF
SURFACE TEMPS WERE TO DROP BELOW FREEZING BY SATURDAY MORNING.
WITH THE EXCEPTION OF ANY LINGERING PRECIP SATURDAY MORNING OVER
THE FAR SOUTHEAST...THE WEEKEND STILL ON TRACK TO BE DRY THOUGH
SATURDAY WILL BE CHILLY OVER MUCH OF THE METRO AREA WITH A LAKE
BREEZE KEEPING THE LAKESHORE AREAS ONLY IN THE 30S. FLOW QUICKLY
SHIFTS SOUTHERLY SATURDAY NIGHT INTO SUNDAY WITH BREEZY SOUTHERLY
WINDS PUSHING TEMPS INTO THE UPPER 50S/LOWER 60S. EXPECT SOME SORT
OF SOUTHEASTERLY COMPONENT ALONG THE IL SHORE...SO LAKESHORE AREAS
FROM DOWNTOWN NORTH COULD BE CONSIDERABLY COLDER.
MODELS CONTINUE TO SLOW THE NEXT LOW MOVING ACROSS THE MIDWEST ON
MONDAY...ONLY TO WESTERN WISCONSIN BY MONDAY EVENING. THIS SHOULD
PROVIDE STRONG SOUTHWESTERLY WINDS OVER THE ENTIRE AREA HELPING TO
PUSH TEMPS INTO THE LOWER 60S OVER MUCH OF THE AREA. HAVE REMOVED
PRECIP MONDAY MORNING EXCEPT THE FAR NORTHWEST AND ADDED THUNDER
BACK TO THE FORECAST FOR THE AFTERNOON. TIMING STILL UNCERTAIN
FROM THIS DISTANCE BUT WITH A COLD FRONT EXPECT TO MOVE ACROSS THE
AREA EITHER LATE MONDAY AFTERNOON OR MONDAY EVENING...THUNDER
LOOKS REASONABLE.
PROGRESSIVE PATTERN CONTINUES WITH ANOTHER STORM SYSTEM LIFTING
NORTHEAST ACROSS THE OHIO VALLEY AND SOUTHERN LAKES REGION TUESDAY
NIGHT THROUGH THURSDAY. MODEL CONSENSUS IS TO KEEP MUCH OF THE
AREA ON THE NORTHERN AND COLDER SIDE OF THIS SYSTEM MAKING PRECIP
TYPE A LITTLE TRICKY. HAVE STAYED RAIN DURING THE DAY WITH A MIX
AT NIGHT MAINLY NORTH...BUT CURRENT THERMAL PROFILES WOULD
SUGGEST MAINLY RAIN THROUGH THE EVENT. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* STRONG AND GUSTY SOUTH WINDS WILL RELAX AND TURN MORE WESTERLY.
* MVFR CIGS WILL PERSIST THROUGH THE MORNING...AND POSSIBLY DROP
TO IFR WITH SECOND WAVE OF RAIN OR LIGHT SNOW. VFR THIS AFTERNOON.
LENNING
//DISCUSSION...UPDATED 06Z...
A STRONG LOW PRESSURE SYSTEM IS EXITING THE AREA THROUGH LOWER
MICHIGAN. AS THE LOW MOVES OUT...WINDS WILL VEER FROM SOUTH TO
WEST OVERNIGHT AND THEN AROUND TO NORTHEAST BY AFTERNOON.
CEILINGS GENERALLY ARE STAYING AT MVFR FOR THE TIME BEING...BUT
RAIN SHOWERS WRAPPING AROUND THE LOW MAY BRIEFLY DROP CIGS TO IFR
TOWARD MORNING AS THEY PASS THROUGH. SKIES LIKELY SCATTER OUT
DURING THE LATE MORNING OR AFTERNOON AS DRIER AIR MOVES IN AHEAD
OF AN APPROACHING HIGH.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM CONFIDENCE ON TIMING OF WIND DIRECTIONAL CHANGES.
* MEDIUM TO HIGH CONFIDENCE ON CEILING TRENDS...THOUGH LOWER
CONFIDENCE REGARDING IFR TOWARD MORNING.
LENNING
//OUTLOOK FOR ORD/MDW FOR 12Z SATURDAY-12Z THURSDAY...UPDATED 00Z...
SATURDAY...VFR. NORTHEAST WINDS.
SUNDAY...VFR. SOUTH WINDS.
MONDAY...CHANCE OF SHRA/TSRA LATE. MODERATE-STRONG SOUTH WINDS.
TUESDAY...VFR PROBABLE. WEST WINDS.
WEDNESDAY...CHANCE OF RAIN AND IFR/MVFR CIGS. NORTHEAST WINDS.
IZZI
&&
.MARINE...
307 AM CDT
A STRONG LOW PRESSURE SYSTEM IS EXITING THE AREA THIS MORNING
ACROSS LOWER MICHIGAN AND LAKE HURON. NORTHWEST TO NORTH GALES
WILL EASE QUICKLY THIS MORNING AS THE LOW PULLS AWAY AND THE
PRESSURE GRADIENT WEAKENS. A RIDGE WILL CROSS THE LAKE ON SATURDAY
BEFORE THE NEXT LOW PRESSURE SYSTEM STARTS TO APPROACH OUT OF THE
CENTRAL PLAINS. ALTHOUGH THIS LOW DOES NOT REACH THE LAKE UNTIL
TUESDAY...SOUTHERLY FLOW AHEAD OF THIS SYSTEM WILL DEVELOP BY
EARLY SUNDAY. A PERIOD OF GALES IS AGAIN POSSIBLE LATE MONDAY
INTO TUESDAY...ESPECIALLY ACROSS THE SOUTHERN HALF OF THE
LAKE...AS THE LOW MOVES THROUGH.
LENNING
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 AM FRIDAY.
GALE WARNING...NEARSHORE WATERS UNTIL 4
AM FRIDAY.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
313 AM CDT Fri Mar 28 2014
.DISCUSSION...
ISSUED 313 AM CDT Fri Mar 28 2014
SHORT TERM...Today through Sunday
Main forecast challenge in the immediate short-term will be timing
the departure of low clouds today. 07z/2am surface analysis shows
low pressure over southern Lake Michigan with cold front trailing
southward along the I-57 corridor. Extensive area of wrap-around
cloud cover is noted on IR satellite imagery blanketing Iowa,
northern Missouri, and western Illinois. With low-level flow
becoming northwesterly, these clouds will spill across central
Illinois early this morning. All model guidance suggests an
overcast start to the day, but how quickly the clouds clear out
remains in question. NAM forecast soundings indicate clouds will
mix out/dissipate between 15z and 18z. Latest HRRR hints at this
as well, although the process may be slower than the NAM
advertises. Given subsidence behind departing upper short-wave and
late March sun working on the low clouds, think skies will
temporarily clear around midday into the early afternoon. After
that, high clouds will quickly begin to increase ahead of the next
approaching system by mid to late afternoon.
Next forecast concern revolves around low pressure expected to
track from Texas into the Tennessee River Valley tonight. Models
have been having difficulty resolving how far north associated
precip will spread. 00z Mar 28 suite is still in disagreement,
with the GFS being the most aggressive in bringing precip furthest
north. Since GFS is often too bullish with light QPF events and
airmass will be drying today, think the NAM has a more realistic
handle on the situation. As such, will keep locations along and
north of a Jacksonville to Bloomington line dry tonight. Best rain
chances will be focused along/south of I-70 in closer proximity to
the low track, with POPs steadily decreasing further northwest.
Despite overnight lows in the middle to upper 30s, NAM forecast
soundings remain warm enough for rain. If colder/further north GFS
verifies, a rain/snow mix may be possible along the northern
fringe of the precip area. Will leave mention of mix out of the
forecast due to skepticism about the GFS QPF field.
After a few lingering showers across the far E/SE KILX CWA
Saturday morning, dry and warmer weather will be the rule this
weekend. As southerly winds develop, high temperatures will climb
into the lower to middle 60s by Sunday.
LONG TERM...Monday through Thursday
Models are still advertising cold frontal passage late Monday,
although amount of available moisture appears to be quite limited.
GFS surface dewpoints are initially around 40 degrees Monday
morning and only climb to the upper 40s to near 50 by late
afternoon. Despite decent upper dynamics associated with vigorous
short-wave, lack of deep moisture return from the Gulf will limit
convective potential. As a result, will only carry low chance for
showers on Monday. Slightly cooler and drier weather will settle
into the region behind the departing front on Tuesday before
another system comes into the picture by mid-week. There are still
some key timing differences with this feature: however, all models
agree that it will have much more moisture to work with. With
short-wave crossing the Rockies into the central CONUS, surface
low pressure is expected to track from eastern Colorado on
Tuesday to the southern Great Lakes by Thursday night. Initial
surge of WAA clouds/precip will arrive Tuesday night into
Wednesday: however, with central Illinois remaining in the cool
sector, very little thunder is expected. Once warm front lifts
northward into the area and low pressure approaches from the
southwest, showers and thunderstorms will become more prevalent
Wednesday night into Thursday.
Barnes
&&
.AVIATION...
ISSUED 1153 PM CDT Thu Mar 27 2014
Band of storms has now passed east of KCMI. Cold front now
approaching KPIA with a wind shift from 200-230 to 260-290. Winds
should remain gusty until the surface low over southwest Wisconsin
pushes into the Great lakes toward 12z.
Low clouds are wrapping around the system and are moving into
KPIA attm and should push into KBMI and KSPI by TAF valid time and
swing into KDEC and KCMI shortly after, Cigs are pretty uniform
low MVFR or high VFR. Since low is pulling away will go with Cigs
in the MVFR range for the most part through mid-morning.
Wave is expected to move northeastward along the front through the
Tennessee Valley. Some question as to how far to the northwest
moisture will be able to extend. Any precip would likely be after
06z. However, VFR Cigs are likely by late afternoon. Although CIGs
may drop into MVFR by 06z at KSPI and KDEC, given the uncertianty
in the extent of moisture will keep things VFR for now.
Barker
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
800 PM EDT SAT MAR 29 2014
.SYNOPSIS...
ISSUED AT 758 PM EDT SAT MAR 29 2014
SKIES WILL CONTINUE TO CLEAR THIS EVENING. OVERNIGHT LOWS WILL BE
COLD IN THE LOWER TO MID 20S. TEMPERATURES WILL THEN WARM UP
NICELY ON SUNDAY INTO THE LOWER TO MID 50S. EVEN WARMER
CONDITIONS ARE ANTICIPATED ON MONDAY AS HIGH TEMPERATURES RISE
INTO THE MID 60S UNDER PARTLY CLOUDY SKIES.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 328 PM EDT SAT MAR 29 2014
NO SIG ISSUES TO WORRY ABOUT FOR THE SHORT TERM AS RAIN/SNOW THAT
HAS FELL ACROSS MUCH OF THE SOUTHERN GREAT LAKES TODAY WAS NEARLY
OUT OF THE FORECAST AREA. FOCUS WILL SHIFT TO CLEARING TONIGHT AND
HOW WARM WE GET ON SUNDAY.
BY IN LARGE THE HEAVIER SNOWBANDS HAVE DIMINISHED WITH REMAINING
RAIN/SNOW ACROSS PORTIONS OF HENRY/PUTNAM AND ALLEN COUNTIES IN
OHIO. SFC LOW WAS OVER NE TENNESSEE AT 18Z AND SLOWLY DEEPENING
WITH AN INCREASING PRESSURE GRADIENT AROUND IT. THIS WILL KEEP
SOMEWHAT BREEZY CONDITIONS MAINLY EAST INTO THIS EVENING BEFORE THE
LOW SHIFTS EAST. LOW CLOUDS HAVE BEEN SLOW TO ERODE IN THE WEST AND
NORTH WITH NAM AND RUC VARYING ON HANDLING OF CLEARING. RUC 925/850
MB RH PLOT HAVE HANDLED THINGS WELL AND LINGER LOW CLOUDS INTO LATE
EVENING WITH NAM MUCH QUICKER ERODING MSTR. WITH VIS SAT SHOWING
HINTS AT SOME THIN SPOTS STARTING TO APPEAR SO HAVE TRIED TO BLEND
THE 2 MODELS WHICH STILL BRINGS GENERALLY CLEAR SKIES BY LATE
EVENING. LOWS WILL DROP INTO THE 20S DESPITE COLDEST AIR WITH THE
SYSTEM ALREADY EAST OF THE REGION AND WAA UNDERWAY LATER TONIGHT.
SOME OF THIS WAA WILL BE REALIZED ON SUNDAY AS LOTS OF SUNSHINE
ALLOWS FOR MIXING THROUGH AT LEAST 900 MB AND MAYBE A BIT HIGHER
YIELDS HIGHS IN THE 50S. WOULDN`T BE ENTIRELY SURPRISED TO SEE SOME
UPR 50S TO NEAR 60 IN FAR W/SW AREAS.
&&
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 PM EDT SAT MAR 29 2014
VERY FEW CHANGES TO OVERALL IDEA IN LONG TERM PERIOD. AN ACTIVE
PATTERN WILL CONTINUE THROUGH THE PERIOD WITH NUMEROUS SHORT WAVES
AND A QUASI STATIONARY BOUNDARY IN THE REGION. THIS SHOULD LEAD TO
RATHER WET PERIOD WITH TEMPERATURES A LITTLE CLOSER TO NORMAL FOR
EARLY APRIL.
RIDGE WILL BE OVER THE AREA SUNDAY NIGHT PROVIDING CLEAR SKIES AND
LIGHT WINDS. LOWS EXPECTED IN THE LOWER 30S EAST UNDER RIDGE AXIS TO
UPPER 30S WEST WHERE WARM AIR ADVECTION ON BACK SIDE OF RIDGE WILL
BE INCREASING. THIS WARMING SHOULD TRANSLATE TO A LARGE DIURNAL
SWING ON MONDAY AS STRONG MIXING DEVELOPS AND WARM AIR ALOFT IS
ALLOWED TO MIX TO SURFACE. SHOULD BECOME BREEZY AS WELL TO HELP
BOOST TEMPERATURES. INCREASING HIGH CLOUDS IN AFTERNOON MAY TEMPER
WARM UP BY A FEW DEGREES DEPENDING ON HOW THICK CLOUD CANOPY IS AND
TIMING OF IT. STILL EXPECT 60S ALL AREAS WITH RUN AT MID TO UPPER
60S ACROSS THE AREA IF SKIES REMAIN MOSTLY SUNNY THROUGH AFTERNOON
PEAK HEATING.
NEXT OF MANY SHORT WAVES MOVES THROUGH THE LAKES REGION MONDAY NIGHT
WITH A TRAILING COLD FRONT THROUGH THE CWA EARLY TUESDAY MORNING.
ENOUGH MOISTURE AND WEAK LIFT TO WARRANT LOW CHANCE POPS BUT
STRONGEST FORCING TO THE NORTH CLOSER TO MAIN LOW. WARMEST TEMPS OF
THE DAY LIKELY IN MORNING BEFORE FROPA BUT DRYING PROFILES TUE
AFTERNOON SUGGEST SUN COULD ALLOW FOR SOME REBOUND SIMILAR TO WHAT
SOME LOCATIONS EXPERIENCED FRIDAY.
DETAILS REMAIN UNCERTAIN FOR REMAINDER OF LONG TERM WITH
AFOREMENTIONED COLD FRONT BECOMING STATIONARY NEAR OR JUST SOUTH OF
CWA. SEVERAL SHORT WAVES ARE EXPECTED WEDNESDAY INTO FRIDAY WITH
ASSOCIATED SURFACE WAVES RIPPLING ALONG FRONTAL BOUNDARY. SEVERAL
CHANCES FOR RAINFALL DURING THE PERIOD WITH UNCERTAINTY IN TIMING.
THUS A CONTINUATION OF BROAD HIGH CHANCE POP CONTINUES WITH FURTHER
INCREASE LIKELY AS TIME NEARS. WITH INCREASING PWATS AND THETA E
AIR...MODERATE TO LOCALLY HEAVY RAINFALL AMOUNTS STILL PLAUSIBLE.
TEMPS DURING THIS PERIOD LIKELY NEAR NORMAL SOUTH AND SLIGHTLY BELOW
NORMAL NORTH BUT IF FRONT WAVERS NORTH OR SOUTH...SIGNIFICANT
CHANGES IN TEMPERATURE FORECASTS WOULD BE EXPECTED.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 757 PM EDT SAT MAR 29 2014
LARGE SCALE SUBSIDENCE AND DRY AIR UNDERCUT BODES WELL FOR EARLIER
TRANSITION TO DOMINANT VFR MET CONDS THAN PRIOR FCSTS FOR NRN IN.
SOME CONCERN FOR AM BR FORMATION ESPCLY IN MAUMEE VALLEY/KFWA
VCNTY. WHILE DRY AIR ADVECTION OVERNIGHT SHOULD GIVE SUFFICIENT
COUNTER TO ARTIFICIALLY HIGH XOVER TEMP...DECOUPLED AIRMASS/WELL
AND RECENTLY WETTED GROUND SUGGEST MODEST VSBY REDUCTION QUITE
LIKELY NEAR DAYBREAK...HOWEVER HAVE REMAINED OPTIMISTIC/ABOVE SIG
LEVELS FOR PLANNING PURPOSES.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...BENTLEY/MURPHY
SHORT TERM...FISHER
LONG TERM...LASHLEY
AVIATION...MURPHY
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AREA FORECAST DISCUSSION
NWS DES MOINES IA
324 PM CDT FRI MAR 28 2014
.SHORT TERM /TONIGHT/...
ISSUED AT 237 PM CDT FRI MAR 28 2014
STRATUS HAS BEEN STUBBORN TO LEAVE AND WHILE CEILINGS WILL RAISE
THROUGH THE EVENING THE LOW STRATUS SHOULD LINGER UNTIL AN UPPER
LEVEL SHORTWAVE SWEEPS EAST THROUGH TONIGHT AND GRADUALLY SCOURS OUT
MOISTURE. SATELLITE IS SHOWING SOME HIGHER LEVEL CLOUDS WITH THIS
FEATURE SO WHILE THE LOW STRATUS CONDITIONS WILL IMPROVE WE SHOULD
STILL KEEP AN OVERCAST CONDITION THROUGH THE EVENING WITH GRADUAL
IMPROVEMENT AFT 08-09Z. CURRENT RADAR IS SHOWING SOME RETURNS OUT
WEST BUT OBSERVATIONS CONFIRM THAT THE PRECIP IS NOT REACHING THE
GROUND. THE NAM12 KEEPS CENTRAL IOWA DRY TONIGHT BUT THE RAP13 DOES
PRINT OUT SOME QPF IN THE BROAD ASCENT AHEAD OF THE SHORTWAVE
PASSING. IT CURRENTLY HAS A GOOD HANDLE ON WHERE PRECIP IS ON THE
RADAR BUT IS OVERDOING IT BECAUSE THERE ARE NO SITES REPORTING
PRECIP SO THE RAP IS LIKELY A BIT OVERDONE. EITHER WAY BOTH MODEL
PRETTY MUCH WIPE ANY PRECIP OUT BEFORE IT MOVES MUCH INTO CENTRAL
IOWA....WITH ONE EXCEPTION...THE RAP DOES DRIBBLE SOME SMALL QPF HERE
AND THERE ACROSS CENTRAL IOWA THROUGH 06Z. FOR NOW I HAVE OPTED TO
KEEP THE FORECAST AREA DRY AND ADVISE THE EVENING SHIFT THAT A
COUPLE OF THE RETURNS ON RADAR...IF THEY HOLD AS THEY COME ACROSS
CENTRAL IOWA...COULD PRODUCE A SPRINKLE OF FLURRY.
TEMPS ARE THE NEXT ISSUE. THE LOW CLOUD COVER REALLY HAMMERED HIGHS
TODAY WITH MOST LOCATIONS IN THE MID TO UPPER 30S. THE STRATUS
EARLY ON WILL KEEP TEMPS UP AND I DO NOT EXPECT MUCH DIURNAL CHANGE
THROUGH THE EVENING. HOWEVER I DO EXPECT CLOUDS TO CLEAR FROM WEST
OR NORTHWEST TO EAST/SOUTHEAST OVERNIGHT. THIS WILL ALLOW A QUICKER
FALL TO TEMPS OVERNIGHT EXCEPT FOR THE FAR SOUTHEAST WHERE CLOUDS
WILL LINGER THE LONGEST. I EITHER WENT ABOVE GUIDANCE OR STAYED ON
THE WARMER SIDE OF IT BASING THAT ON CLOUDS HANGING AROUND LONGER.
.LONG TERM /SATURDAY THROUGH FRIDAY/...
ISSUED AT 237 PM CDT FRI MAR 28 2014
THE TRANSITION FROM WINTER TO SPRING APPEARS TO BE WELL UNDERWAY.
THE PATTERN FOR THE NEXT WEEK LOOKS SEASONABLY ACTIVE WITH
MULTIPLE SHORTWAVES MOVING THROUGH IN WESTERLY PROGRESSIVE FLOW.
SATURDAY AND SUNDAY...GENERAL SUBSIDENCE BEHIND TONIGHT/S
SHORTWAVE WILL PREVAIL ON SATURDAY. SURFACE RIDGE MOVES EAST BY
EVENING. TEMPERATURES WILL RECOVER NICELY REACHING THE 50S IN MOST
LOCATIONS. RIDGING ALOFT SATURDAY NIGHT AND SUNDAY AHEAD OF A
POTENT SHORTWAVE SHOULD RESULT IN THE WARMEST TEMPERATURES SINCE
LAST FALL ON SUNDAY. THE WARM UP HAS BEEN FORECAST FOR DAYS AND
KEPT WARM TEMPERATURES GOING. BASED WINDS ON MIXED LAYER WINDS OR
SLIGHTLY LESS SINCE IT IS A WARM ADVECTION SITUATION.
MONDAY AND TUESDAY...USED 12Z ECMWF/GFS TO BASE FORECAST. 12Z NAM
APPEARED TO BE AN OUTLIER. THE ECMWF/GFS WERE SLOWER AND STRONGER
WITH THE SHORTWAVE ENERGY EMERGING FROM THE CENTRAL ROCKIES AT 12Z
MONDAY. BOTH SOLUTIONS BRING A NEGATIVELY TILTED SHORTWAVE THROUGH
CENTRAL IOWA ON MONDAY. THE ECMWF IS NORTH OF THE GFS SURFACE LOW
POSITION AT 00Z TUESDAY. CENTRAL IOWA WILL BE IN THE WARM SECTOR
WITH A COLD FRONT MOVING INTO THE WESTERN COUNTIES BY AFTERNOON
AND A SURFACE LOW EITHER IN NORTHWEST IOWA OR NEARBY. LOOKING AT
THE MODEL SOUNDINGS...THE LIMITING FACTOR FOR SEVERE WEATHER WILL
BE TIMING CONSIDERATIONS AND THE AMOUNT OF LOW-LEVEL MOISTURE
TRANSPORTED INTO IOWA AHEAD OF THE SYSTEM. IF THINGS COME TOGETHER
IT COULD GET INTERESTING MONDAY EVENING IN CENTRAL IOWA. SHEAR
PARAMETERS ARE VERY FAVORABLE. FINALLY...THE WEATHER PATTERN IS ON
PAR FOR THE TIME OF YEAR. THERE HAVE BEEN NUMEROUS SEVERE WEATHER
EVENTS IN CENTRAL IOWA BETWEEN MARCH 31ST AND APRIL 12TH OVER THE
YEARS.
COLD AIR WILL MOVE BACK IN THE WAKE OF THIS SYSTEM AND TUESDAY
LOOKS DRY BUT COOLER AND BREEZY.
WEDNESDAY THROUGH FRIDAY...ACTIVE PATTERN CONTINUES. MODELS ARE IN
POOR AGREEMENT WITH THE DETAILS AT THIS RANGE. HOWEVER...IT
APPEARS LIKELY THAT ANOTHER STORM SYSTEM WILL IMPACT THE MIDWEST
LATE IN THE WEEK. CONFIDENCE CONCERNING THE FORECAST DETAILS ARE
BELOW AVERAGE AT THAT POINT.
&&
.AVIATION...28/18Z
ISSUED AT 1246 PM CDT FRI MAR 28 2014
STRATUS WILL BE HANGING IN LONGER THAN PREVIOUSLY THOUGHT. I HAVE
KEPT AN IFR FORECAST GOING INTO THE EVENING...UNTIL THE UPPER LEVEL
SHORTWAVE PASSES AND SCOURS OUT SOME OF THE MOISTURE. CIGS WILL
GRADUALLY IMPROVE THROUGH THE OVERNIGHT HOURS ALTHOUGH IF CLOUDS
BREAK WE COULD SEE SOME MVFR FOG CONDITIONS FOR A COUPLE HOURS. AFT
14-15Z JUST SOME SCT CLOUDS.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...FAB
LONG TERM...JOHNSON
AVIATION...FAB
AREA FORECAST DISCUSSION
NWS TOPEKA KS
556 PM CDT Fri Mar 28 2014
...AVIATION UPDATE...
.SHORT TERM...(This Evening through Saturday)
Issued at 342 PM CDT FRI MAR 28 2014
Center of upper wave moving across South Dakota today with another
wave crossing Texas. Enough forcing and moisture for scattered very
light precip across much of Kansas today. Light winds and little
insolation keeping temps in the middle 40s at 20Z. Visible satellite
showing additional precip attempting to form in southwest Nebraska
and northwest Kansas in steep low level lapse rates just ahead of
the trough axis.
Should see back edge of precip exiting east central Kansas by sunset
with clearing already occurring in central portions of the state.
Any convective activity to the west would likely not arrive until
after sunset, given its diurnal nature am not expecting much if
anything to survive this far east. Clear skies and light winds in a
reinforcing low level ridge overnight, but rather dry boundary layer
should keep fog in check. Upper heights rise Saturday with surface
ridge passing through in the daytime keeps winds on the lighter side
again with modest warm air advection as high clouds slowly increase.
Highs in the low to mid 60s remain on track. RH values dipping into
the middle 20s will likely keep elevated fire danger conditions
going for the west.
.LONG TERM...(Saturday Night through Friday)
Issued at 342 PM CDT FRI MAR 28 2014
Early on is the concern for winds on Sunday as 850 MB winds increase
to 40 to 45 kts by the afternoon hours. Forecast soundings show
mixing up to 825 MB with temperatures in the mid to upper 70s.
Afternoon relative humidity expected near or below 30 percent and
given the dry fuels expect high to very high fire danger on Sunday.
Also winds will increase to near 25 mph with gusts as high as 40 mph
not out of the question. Most likely will need a wind advisory for
Sunday.
Sunday night elevated showers and thunderstorms are possible across
the CWA after midnight when the low level jet increases ahead of an
approaching upper trough moving out of the Rockies. The trough moves
northeast from southwest Kansas into south central Nebraska during
the morning hours on Monday with a dry slot moving across eastern
Kansas. Wrap around precipitation is possible to the north of the
Nebraska border in the afternoon. A pacific cool front will move
across the CWA during the day on Monday. Will leave a dry forecast
for now, but this will need to be monitored.
Tuesday night increasing moisture and instability is forecast across
northern Kansas as the low level jet increases from the south. Good
moisture fetch from the gulf into the Southern and Central Plains.
Warm front sets up south of the CWA across southern Kansas with
isentropic lift increasing northward over the CWA especially after
midnight.
Wednesday looking like a busy day with potential for severe
thunderstorms across the CWA. Shear, instability and moisture coming
together along with the warm front sliding northward into the CWA in
the afternoon hours. Another Pacific front will move through
Thursday as the upper low moves across the Central Plains. Kept
chances of showers as instability shifts off to the east into the
Mid Mississippi Valley by evening. There is uncertainty in the track
of the upper low with the ECMWF further north and the GFS south
across Kansas. This will have an impact on both temperatures and
precipitation placement. Friday looking dry as the upper system is
well east. Temperatures for much of next week will average near or
below normal.
&&
.AVIATION...(For the 00Z TAFs through 00Z Saturday Evening)
Issued at 556 PM CDT FRI MAR 28 2014
With TOP reporting reduced VSBY for much of the day, am a little
concerned for the development of ground fog since the boundary
layer never really mixed out. RAP and NAM forecast soundings also
suggest there could be some shallow fog. At this time will mention
some MVFR VSBY at TOP overnight. MHK and FOE mixed out better
through the afternoon so think boundary layer moisture may be more
limited and fog potential is lower given some dry air advection
through the night. Otherwise conditions should be fine with
surface ridging over the area through the morning Saturday.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...65
LONG TERM...53
AVIATION...Wolters
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
226 PM EDT FRI MAR 28 2014
.UPDATE...
ISSUED AT 210 PM EDT FRI MAR 28 2014
GRIDS WERE FRESHENED UP BASED ON THE LATEST OBSERVATION TRENDS.
SHOWER ACTIVITY IS NEXT TO NIL ACROSS THE REGION IN ADVANCE OF THE
COLD FRONT. THIS IS LIKELY DUE TO SOME MID LEVEL CAPPING AS SHORTWAVE
MID LEVEL RIDGING BETWEEN THE DEPARTING SHORTWAVE AND THE NEXT
SYSTEMS WORKS ACROSS THE OH VALLEY REGION. SHOWER ACTIVITY THIS
AFTERNOON SHOULD BE MINIMAL...IF ANY AT ALL ACROSS THE REGION. AT
THIS TIME...WE PLAN TO LET THE SLIGHT CHANCE POPS RIDE SINCE THE NAM
AND GFS AS WELL AS THE HRRR STILL HAVE SOME CONVECTION LATER THIS
AFTERNON AND INTO THE EVENING.
UPDATE ISSUED AT 1120 AM EDT FRI MAR 28 2014
THE PREFRONTAL CONVECTION HAS EXITED TO THE SOUTH AND EAST...ALTHOUGH
THE COLD FRONT IS ONLY MAKING SLOW SOUTHEAST PROGRESS AND IS NEAR OR
JUST WEST OF THE INTERSTATE 65 CORRIDOR. A MID LEVEL SHORTWAVE OVER
THE GREAT LAKES REGION IS EXITING TO THE NORTH AND EAST OF THE AREA.
A RELATIVE LULL IN ACTIVITY IS ANTICIPATED BETWEEN THIS DEPARTING
SHORTWAVE AND THE NEXT WAVE TO APPROACH THE AREA TONIGHT. THUS...POPS
HAVE BEEN LOWERED TO SLIGHT CHANCE FOR THE REMAINDER OF THE DAY INTO
THE EVENING. ALSO...HOURLY SKY...TEMPS AND DEWPOINTS HAVE BEEN FINE
TUNED TO REFLECT RECENT OBSERVATIONS AS WELL AS SATELLITE AND RADAR
IMAGERY.
UPDATE ISSUED AT 800 AM EDT FRI MAR 28 2014
THE THUNDERSTORMS WITH THE COLD FRONT ARE FADING OUT NOW SO HAVE
BACKED OFF OF THEM TO JUST AN ISOLATED MENTION IN THE GRIDS. HAVE
TIMED THE CORE OF THE PCPN THROUGH THE AREA FROM WEST TO EAST FROM 12
TO 15Z. ALSO...FINE TUNED TEMPS AND DEWPOINTS THROUGH THE NEXT
SEVERAL HOURS WITH THIS UPDATE PER THE LATEST OBS AND TRENDS. THESE
HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 335 AM EDT FRI MAR 28 2014
06Z SFC ANALYSIS SHOWS A DEEP AREA OF LOW PRESSURE MOVING THROUGH THE
GREAT LAKES WITH A SHARP COLD FRONT ENTERING THE OHIO VALLEY. THIS
BOUNDARY IS SHOWING UP WELL ON RADAR AS A THIN LINE OF SHOWERS AND
THUNDERSTORMS DROPPING SOUTHEAST TOWARD KENTUCKY. SCATTERED TO
NUMEROUS SHOWERS ARE FOUND OUT AHEAD OF THIS LINE THROUGH CENTRAL
EASTERN KENTUCKY. THIS ADVANCE CONVECTION IS WORKING TO MOISTEN UP
THE VERY DRY AIR OVER EAST KENTUCKY AND THUS FAR NOT AMOUNTING TO TOO
MUCH ACCUMULATION. HAVE TIMED THE FRONT INTO EAST KENTUCKY AROUND 12Z
AND THROUGH BY 15Z...HIGHLIGHTING THIS TIME FRAME WITH THE HIGHEST
POPS AND BEST CHANCE FOR THUNDER. IN THE MEANTIME...GUSTY SHOWERS AND
SPRINKLES WILL CONTINUE OVER THE CWA. AHEAD OF THE FRONT THE
TEMPERATURES ARE REMAINING QUITE MILD WITH READINGS GENERALLY IN THE
LOW TO MID 50S. DEWPOINTS VARY FROM THE LOWER 40S IN THE WEST TO
AROUND 30 IN THE FAR EAST. OUTSIDE OF THE HIGHER GUSTS IN SHOWERS...
WINDS ARE RUNNING FROM THE SOUTH TO SOUTHWEST AT 10 TO 15 MPH WITH
GUSTS TO 25 MPH. HIGHER SUSTAINED SPEEDS AND GUSTS TO 35 MPH ARE
STILL POSSIBLE WITH THE SHOWERS...PARTICULARLY OVER THE NORTHERN AND
WESTERN PARTS OF THE CWA.
THE MODELS ARE IN DECENT AGREEMENT ALOFT WITH THE SHALLOW TROUGH
PASSING THROUGH THE GREAT LAKES THIS MORNING. THIS IS FOLLOWED BY
SOUTHWEST FLOW AND AN AMPLIFYING TROUGH OVER THE CENTRAL PLAINS INTO
TONIGHT. THIS NEXT TROUGH IMPRESSIVELY DEEPENS AS IT MOVES INTO THE
AREA AND RIGHT OVER KENTUCKY ON SATURDAY. THIS FEATURE NEARLY CLOSES
OFF AND IS SURPRISINGLY SIMILAR IN THE MODELS AT 00Z SUNDAY WITH THE
GEM AND GFS THE STRONGEST. THE ECMWF AND NAM ARE A BIT WEAKER...BUT
THE PATTERNS AND TIMING ALL MATCH UP WELL. GIVEN THIS...HAVE GONE
WITH A GENERAL MODEL BLEND AND FOLLOW SPECIFICS FROM THE NAM12 AND
GFS.
SENSIBLE WEATHER WILL FEATURE A VERY ACTIVE AND CHANGEABLE SHORT TERM
PORTION OF THE FORECAST. FOR STARTERS...SHOWERS AND A POSSIBLE
THUNDERSTORM...WILL CROSS THROUGH ALL OF EAST KENTUCKY THIS MORNING
AS A COLD FRONT MOVES THROUGH. LOOK FOR CLOUDY SKIES TO REMAIN ALONG
WITH SOME LINGERING SHOWERS FOR THE AFTERNOON...ESPECIALLY OVER THE
SOUTHEAST. THIS FRONT WILL SETTLE JUST SOUTH OF THE AREA THIS EVENING
AND QUICKLY REACTIVATE OVER THE WEST BY MIDNIGHT. THIS NEXT WAVE...
DRIVEN BY THE APPROACHING AND STRENGTHENING MID LEVEL TROUGH...WILL
CONSOLIDATE OVER THE TENNESSEE VALLEY BY EARLY SATURDAY MORNING AND
RETURN SHOWERS AND POSSIBLE THUNDERSTORMS TO EAST KENTUCKY. THE
CENTER OF THIS LOW WILL PASS THROUGH FAR SOUTHEAST KENTUCKY DURING
THE DAY AND START TO PULL IN COLDER AIR FROM THE NORTH. THERE IS
STRONG MODEL SUPPORT FOR THE COLUMN OF AIR COOLING ENOUGH BY LATE
AFTERNOON IN THE NORTHWEST PARTS OF THE CWA TO RESULT IN A CHANGEOVER
TO SNOW. SFC TEMPERATURES WILL STAY UP WELL ABOVE FREEZING THROUGH
00Z SUNDAY SO ANY ACCUMULATIONS WILL HOLD OFF UNTIL LATER THAT NIGHT.
FOR TEMPERATURES...WINDS...AND DEW POINTS USED THE BC/CONSSHORT AS A
STARTING POINT THROUGH THE EARLY OVERNIGHT HOURS OF SATURDAY. AFTER
THAT USED AN ADJUSTED VERSION OF THE RAW NAM FOR TEMPS AND THE
BC/CONSALL FOR TD AND WINDS. AS FOR POPS...ENDED UP RATHER WET AND IN
LINE WITH THE MOS GUIDANCE.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 330 AM EDT FRI MAR 28 2014
THE EXTENDED FORECAST PERIOD BEGINS ON SATURDAY NIGHT WITH A
PROGRESSIVE AND ACTIVE PATTERN IN PLACE AS A STRONG SHORTWAVE IS
MOVING THROUGH THE OH AND TN VALLEY AT THIS TIME AND MOVES UP THE
EAST COAST BY SUNDAY NIGHT. AFTER THAT...MID LEVEL RIDGING CAUSES A
FAST MOVING SHORT WAVE TO MOVE NORTHEAST INTO THE GREAT LAKES REGION
AND INTO NEW ENGLAND BY TUESDAY. AFTER THIS...A BROAD CLOSED LOW
CROSSES THE FRONT RANGE AND INTO THE CENTRAL PLAINS BY TUESDAY NIGHT
AND INTO WEDNESDAY. THIS WAVE DEEPENS AS IT THEN MOVES INTO THE MS
RIVER VALLEY ON THURSDAY. THE GFS AND EURO SEEM TO BE IN DECENT
AGREEMENT WITH THIS PATTERN...ESPECIALLY WITH THE LOW TOWARDS THE
END OF THE EXTENDED WHICH COULD BE A SIGNIFICANT EVENT.
IN THE LOWER LEVELS FOR SATURDAY NIGHT...THE COLDER AIR FILTERING IN
BEHIND THE FRONT THAT PASSED THROUGH ON SATURDAY WILL MAKE INTO THE
AREA FAST ENOUGH FOR RAIN TO CHANGE TO SNOW. IN FACT...WITH THE
SMALL LAYER OF DRIER AIR AT THE SURFACE FOR SOME WET BULBING...THE
COLDER AIR NOT FAR OFF THE SURFACE...AND THE CONVECTIVE PROPERTIES
OF THE SHOWERS...WILL NOT BE SURPRISED TO SEE SNOW AT 35 DEGREES AT
THE SURFACE. WITH THE DEPTH OF THE MOIST LAYER AND THE OMEGA
AVAILABLE...HAVE ALSO PUT IN SOME ACCUMULATING SNOW IN THE FORECAST
WITH MAINLY THE BLUE GRASS AND THE HIGHER TERRAIN IN THE NORTH AND
EAST. THE FRONT MOVING THROUGH ON TUESDAY LOOKS TO DRY OUT AS IT
APPROACHES THE AREA. THE BEST DYNAMICS TAKE A FARTHER TRACK NORTH
AND HAVE LEFT SLIGHT CHANCE POPS NORTH OF THE FORECAST AREA.
HOWEVER...WILL NOT BE SURPRISED TO SEE SOME SPRINKLES POP UP TUESDAY
AFTERNOON. ANY HINT THAT THE DEVELOPING SHOWERS WILL NOT SHEAR OUT
AND SOME ADDITIONAL MOISTURE AVAILABLE...THE CHANCE IS THERE FOR SOME
SHOWERS AND AN ISOLATED THUNDERSTORM. THERE IS A GOOD BIT OF SURFACE
INSTABILITY TUESDAY AFTERNOON. FOR NOW...WILL KEEP THIS PERIOD DRY.
WITH MOST LIKELY A DRY PERIOD CONTINUING INTO WEDNESDAY...THE SET UP
TOWARDS THE END OF THE EXTENDED WILL CHANGE THIS DRY PATTERN.
SURFACE HIGH PRESSURE SETS UP OVER THE SOUTHEAST AND PROVIDING WARM
MOIST SOUTHERLY FLOW INTO THE OH VALLEY AHEAD OF THE NEXT
APPROACHING POTENT SYSTEM WILL BRING SHOWERS AND THUNDERSTORMS INTO
THE AREA LATE WEDNESDAY AND THROUGH THE REST OF THE EXTENDED. THIS
SET UP WILL BE ONE TO WATCH FOR HOW IT DEVELOPS. A LOT CAN CHANGE IN
THE MODELS BETWEEN NOW AND THEN BUT THE POTENTIAL FOR SEVERE WEATHER
IS PRESENT WITH THIS SET UP.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 210 PM EDT FRI MAR 28 2014
A COLD FRONT HAS BEGUN TO STALL ACROSS THE OH VALLEY REGION AS THE
FIRST SFC LOW AND ASSOCIATED MID LEVEL DISTURBANCE DEPART AND SFC LOW
PRESSURE BEGINS TO ORGANIZE OVER THE SOUTHERN PLAINS. THIS NEXT SFC
LOW WILL TRACK ACROSS THE AREA LATE TONIGHT AND INTO SAT. SOME LOCATIONS
SHOULD IMPROVE TO VFR FOR A WHILE OVER THE FIRST 6 TO 9 HOURS OF THE
PERIOD IN BETWEEN SYSTEMS. CLOUDS WILL REMAIN...JUST ABOVE THE MVFR
VFR BREAK IN LOCATIONS THAT DO IMPROVE TO VFR. THIS NEXT LOW WILL
BRING RENEWED CHANCES FOR SHOWERS AND POSSIBLY ISOLATED TSRA AS WELL
AS ANOTHER LOWERING OF CONDITIONS BACK TO MVFR BETWEEN 8Z AND 14Z.
THIS WILL BE AFTER
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...GREIF
LONG TERM...SHALLENBERGER
AVIATION...JP
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1229 PM CDT FRI MAR 28 2014
.AVIATION UPDATE...REGARDING 18Z TAF ISSUANCE. MVFR AND IFR
CEILINGS CAN BE EXPECTED TODAY AS A MOIST SOUTHERLY FLOW
CONTINUES. A FEW SHOWERS WILL BE POSSIBLE DURING THE
AFTERNOON...WITH INCREASING SHOWERS ALONG WITH THUNDERSTORMS INCOMING
FROM THE WEST GOING INTO THE EVENING HOURS. THIS ALONG AND AHEAD
OF OUR NEXT FRONTAL PASSAGE. CURRENTLY CARRYING PREVAILING FOR
THUNDER AT AEX WHERE LIFT WILL BE SOMEWHAT STRONGER FOR
CONVECTION...AND TEMPO GROUPS AT OUR SOUTHERN TERMINALS. COULD NOT
RULE OUT SOME STRONG OR EVEN SEVERE THUNDERSTORMS...AGAIN WITH
BEST CHANCES AT AEX. OTHERWISE...RAINS WILL TAPER OFF WITH THE
FRONTAL PASSAGE...BUT EXPECTING IFR CEILINGS AND SOME BR TO HOLD
POST-FRONTAL AS DRIER AIR SURFACE AIR WILL BE SLOW TO FILTER IN.
EXPECTING CLEARING SKIES WEST TO EAST POST-SUNRISE SATURDAY.
&&
MARCOTTE
&&
.PREV DISCUSSION... /ISSUED 1030 AM CDT FRI MAR 28 2014/
UPDATE...
ADJUSTED THE POPS DOWNWARD A LITTLE FOR MOST PLACES FOR THE
REMAINDER OF THE MORNING AND AFTERNOON. LOOKS LIKE CAP SHOULD HOLD
ENOUGH THAT JUST WIDELY SCATTERED SHOWERS...MAINLY LIGHT...UNDER
THE CAP WILL BE ALL THAT CAN GET GOING. AFTER 21Z...4 PM...UPPER
LEVEL SUPPORT WILL BE MOVING TOWARD THE REGION...THIS MAY ALLOW
FOR SOME STRONGER SHOWERS AND STORMS TO DEVELOP OVER WESTERN
PORTIONS OF SOUTHEAST TEXAS...TYLER AND HARDIN COUNTIES...SO HAVE
KEPT HIGHER POPS IN THIS AREA...WITH THE MENTION OF POSSIBLE
SEVERE. ALSO...VISIBILITIES HAVE BEEN IMPROVING OVER THE MARINE
AREAS A LITTLE QUICKER THAN PREVIOUSLY EXPECTED...WITH
VISIBILITIES AT CAMERON UP TO 2 MILES...AND PLATFORMS SOUTHEAST OF
GALVESTON AND SOUTH OF MARSH ISLAND ALSO AROUND 2 MILES. EXPECT A
LITTLE MORE IMPROVEMENT OVER THE NEXT COUPLE OF HOURS AS WARMING
PROVIDES ENOUGH INSTABILITY TO HELP BRIEFLY LIFT THE FOG OR MAKE
IT MORE PATCHY IN NATURE. THEREFORE...WILL HAVE THE MARINE DENSE
FOG ADVISORY EXPIRE AT NOON TIME.
RUA
PREV DISCUSSION... /ISSUED 638 AM CDT FRI MAR 28 2014/
AVIATION...LIFR AND IFR CEILINGS WILL CONTINUE THROUGH THE MOST
OF THE MORNING ALONG WITH REDUCED VIS IN BR AND -RA. CONDITIONS
WILL GRADUALLY IMPROVE FROM LATE MORNING INTO THE AFTERNOON,
HOWEVER ADDITIONAL RAIN AND THUNDERSTORMS WILL DEVELOP DURING THE
AFTERNOON AND EVENING. THIS WILL REDUCE CEILINGS AND VIS ONCE
AGAIN. RAIN CHANCES WILL DECREASE PAST MIDNIGHT WITH FG DEVELOPING
TOWARD SAT MORNING. WINDS WILL BE SE TO SW TODAY AT 12 KTS OR LESS
OUTSIDE OF STORMS. WINDS MAY BECOME GUSTY AND ERRATIC IN OR NEAR STORMS.
PREV DISCUSSION... /ISSUED 531 AM CDT FRI MAR 28 2014/
DISCUSSION...
SHOWERS AND THUNDERSTORMS CONTINUE OVER MAINLY EAST CENTRAL
LOUISIANA THIS MORNING...GENERALLY WITHIN AREA OF ENHANCED LOW
LEVEL MSTR INFLUX/CONVERGENCE AND BENEATH DIVERGENCE ALOFT
ENHANCED BY COUPLED JET STRUCTURE BETWEEN SUB-TROPICAL JET AND JET
MAX ASSOCIATED WITH SHORTWAVE TROF LIFTING THROUGH THE UPPER
MIDWEST. UPSTREAM WATER VAPOR IMAGERY CONTINUES TO DEPICT AN
ACTIVE SUB-TROPICAL JET...WITH ANOTHER SHORTWAVE TROF JUST PASSING
EAST OF THE FOUR CORNERS.
THE ONGOING ACTIVITY IS EXPECTED TO GENERALLY SHIFT EASTWARD THIS
MORNING...WITH A GENERAL LULL IN ACTIVITY EXPECTED UNTIL THE APPROACH
OF THIS UPSTREAM SHORTWAVE LATER THIS AFTERNOON. HRRR AND OTHER
MESOSCALE MODELS INDICATE CONVECTION INITIATING OVER CENTRAL/EAST
TEXAS EARLY TO MID AFTERNOON...WITH SUBSEQUENT DOWNSTREAM
MOVEMENT/DEVELOPMENT ACROSS THE FORECAST AREA THIS EVENING. THE MARINE
LAYER MAY PROVE DETRIMENTAL OVER THE COASTAL COUNTIES/PARISHES...BUT
INSTABILITY IS OVERALL PROGGED TO BE GREATER THAN IT WAS ON
THURSDAY...WITH THE ADDITION OF SFC FEATURES...LIKE THE APPROACHING
CDFNT...TO BETTER FOCUS DEVELOPMENT. SPC HAS ENTIRE AREA OUTLINE
IN A SLIGHT RISK...WITH LARGE HAIL/DAMAGING WINDS THE PRIMARY
HAZARDS. LOW LEVEL SHEAR/HELICITY...WHILE NOT PRECLUDING
TORNADOES...SUGGESTS THE RISK IS SUBORDINATE TO THE OTHER TWO.
DECREASING WINDS HAVE SUBSEQUENTLY RESULTED IN DECREASING VSBYS
OVER THE COASTAL WATERS AS WELL AS INLAND. SUFFICIENT TURBULENT
MIXING WILL LIKELY PREVENT INLAND VSBYS FROM REACHING DENSE FOG
CRITERIA...BUT REFER TO THE MARINE DISCUSSION BELOW FOR THE COASTAL
WATERS.
THE CDFNT IS PROGGED TO SWEEP THROUGH THE REGION LATE TONIGHT...WITH
COOLER AND DRIER AIR GIVING WAY TO A PLEASANT WEEKEND. RAIN
CHANCES LOOK TO RETURN FOR THE MID TO LATTER PART OF THE WEEK AMID
THE RETURN OF A WAA REGIME AND ACTIVE SUB-TROPICAL JET.
13
MARINE...
SOUTH WINDS HAVE STEADILY DECREASED EARLY THIS MORNING...WHICH IS
PERMITTING A SLOWER TRANSPORT OF MOISTURE LADEN AIR OVER
RELATIVELY COOLER SHELF WATERS. THE RESULT HAS BEEN A STEADY
DECREASE IN VISIBILITIES SEEN AT OFFSHORE AND COASTAL REPORTING
SITES. WITH THIS PATTERN EXPECTED TO REMAIN IN PLACE UNTIL A COLD
FRONT PASSES EARLY SATURDAY...CONDITIONS WILL CONTINUE TO SUPPORT
MARINE FOG FORMATION. A MARINE FOG ADVISORY HAS BEEN ISSUED...AND
MAY NEED TO BE EXTENDED BEYOND THE CURRENT EXPIRATION TIME OF 7 PM
CDT. GOOD CHANCES OF SHOWERS AND THUNDERSTORMS ARE EXPECTED UNTIL
THIS COLD FRONT MOVES THROUGH THE REGION LATE FRIDAY NIGHT INTO
EARLY SATURDAY. A MODEST OFFSHORE FLOW IS EXPECTED OVER THE
WEEKEND IN THE WAKE OF THE FRONT...WITH SOUTHERLY WINDS RETURNING
TO START THE WORK WEEK.
13
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 62 76 49 72 50 / 60 10 10 10 10
KBPT 62 78 52 73 53 / 50 10 10 10 10
KAEX 57 72 44 73 46 / 60 10 10 10 10
KLFT 63 74 49 73 49 / 60 10 10 10 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1030 AM CDT FRI MAR 28 2014
.UPDATE...
ADJUSTED THE POPS DOWNWARD A LITTLE FOR MOST PLACES FOR THE
REMAINDER OF THE MORNING AND AFTERNOON. LOOKS LIKE CAP SHOULD HOLD
ENOUGH THAT JUST WIDELY SCATTERED SHOWERS...MAINLY LIGHT...UNDER
THE CAP WILL BE ALL THAT CAN GET GOING. AFTER 21Z...4 PM...UPPER
LEVEL SUPPORT WILL BE MOVING TOWARD THE REGION...THIS MAY ALLOW
FOR SOME STRONGER SHOWERS AND STORMS TO DEVELOP OVER WESTERN
PORTIONS OF SOUTHEAST TEXAS...TYLER AND HARDIN COUNTIES...SO HAVE
KEPT HIGHER POPS IN THIS AREA...WITH THE MENTION OF POSSIBLE
SEVERE. ALSO...VISIBILITIES HAVE BEEN IMPROVING OVER THE MARINE
AREAS A LITTLE QUICKER THAN PREVIOUSLY EXPECTED...WITH
VISIBILITIES AT CAMERON UP TO 2 MILES...AND PLATFORMS SOUTHEAST OF
GALVESTON AND SOUTH OF MARSH ISLAND ALSO AROUND 2 MILES. EXPECT A
LITTLE MORE IMPROVEMENT OVER THE NEXT COUPLE OF HOURS AS WARMING
PROVIDES ENOUGH INSTABILITY TO HELP BRIEFLY LIFT THE FOG OR MAKE
IT MORE PATCHY IN NATURE. THEREFORE...WILL HAVE THE MARINE DENSE
FOG ADVISORY EXPIRE AT NOON TIME.
RUA
&&
.PREV DISCUSSION... /ISSUED 638 AM CDT FRI MAR 28 2014/
AVIATION...LIFR AND IFR CEILINGS WILL CONTINUE THROUGH THE MOST
OF THE MORNING ALONG WITH REDUCED VIS IN BR AND -RA. CONDITIONS
WILL GRADUALLY IMPROVE FROM LATE MORNING INTO THE AFTERNOON,
HOWEVER ADDITIONAL RAIN AND THUNDERSTORMS WILL DEVELOP DURING THE
AFTERNOON AND EVENING. THIS WILL REDUCE CEILINGS AND VIS ONCE
AGAIN. RAIN CHANCES WILL DECREASE PAST MIDNIGHT WITH FG DEVELOPING
TOWARD SAT MORNING. WINDS WILL BE SE TO SW TODAY AT 12 KTS OR LESS
OUTSIDE OF STORMS. WINDS MAY BECOME GUSTY AND ERRATIC IN OR NEAR STORMS.
PREV DISCUSSION... /ISSUED 531 AM CDT FRI MAR 28 2014/
DISCUSSION...
SHOWERS AND THUNDERSTORMS CONTINUE OVER MAINLY EAST CENTRAL
LOUISIANA THIS MORNING...GENERALLY WITHIN AREA OF ENHANCED LOW
LEVEL MSTR INFLUX/CONVERGENCE AND BENEATH DIVERGENCE ALOFT
ENHANCED BY COUPLED JET STRUCTURE BETWEEN SUB-TROPICAL JET AND JET
MAX ASSOCIATED WITH SHORTWAVE TROF LIFTING THROUGH THE UPPER
MIDWEST. UPSTREAM WATER VAPOR IMAGERY CONTINUES TO DEPICT AN
ACTIVE SUB-TROPICAL JET...WITH ANOTHER SHORTWAVE TROF JUST PASSING
EAST OF THE FOUR CORNERS.
THE ONGOING ACTIVITY IS EXPECTED TO GENERALLY SHIFT EASTWARD THIS
MORNING...WITH A GENERAL LULL IN ACTIVITY EXPECTED UNTIL THE APPROACH
OF THIS UPSTREAM SHORTWAVE LATER THIS AFTERNOON. HRRR AND OTHER
MESOSCALE MODELS INDICATE CONVECTION INITIATING OVER CENTRAL/EAST
TEXAS EARLY TO MID AFTERNOON...WITH SUBSEQUENT DOWNSTREAM
MOVEMENT/DEVELOPMENT ACROSS THE FORECAST AREA THIS EVENING. THE MARINE
LAYER MAY PROVE DETRIMENTAL OVER THE COASTAL COUNTIES/PARISHES...BUT
INSTABILITY IS OVERALL PROGGED TO BE GREATER THAN IT WAS ON
THURSDAY...WITH THE ADDITION OF SFC FEATURES...LIKE THE APPROACHING
CDFNT...TO BETTER FOCUS DEVELOPMENT. SPC HAS ENTIRE AREA OUTLINE
IN A SLIGHT RISK...WITH LARGE HAIL/DAMAGING WINDS THE PRIMARY
HAZARDS. LOW LEVEL SHEAR/HELICITY...WHILE NOT PRECLUDING
TORNADOES...SUGGESTS THE RISK IS SUBORDINATE TO THE OTHER TWO.
DECREASING WINDS HAVE SUBSEQUENTLY RESULTED IN DECREASING VSBYS
OVER THE COASTAL WATERS AS WELL AS INLAND. SUFFICIENT TURBULENT
MIXING WILL LIKELY PREVENT INLAND VSBYS FROM REACHING DENSE FOG
CRITERIA...BUT REFER TO THE MARINE DISCUSSION BELOW FOR THE COASTAL
WATERS.
THE CDFNT IS PROGGED TO SWEEP THROUGH THE REGION LATE TONIGHT...WITH
COOLER AND DRIER AIR GIVING WAY TO A PLEASANT WEEKEND. RAIN
CHANCES LOOK TO RETURN FOR THE MID TO LATTER PART OF THE WEEK AMID
THE RETURN OF A WAA REGIME AND ACTIVE SUB-TROPICAL JET.
13
MARINE...
SOUTH WINDS HAVE STEADILY DECREASED EARLY THIS MORNING...WHICH IS
PERMITTING A SLOWER TRANSPORT OF MOISTURE LADEN AIR OVER
RELATIVELY COOLER SHELF WATERS. THE RESULT HAS BEEN A STEADY
DECREASE IN VISIBILITIES SEEN AT OFFSHORE AND COASTAL REPORTING
SITES. WITH THIS PATTERN EXPECTED TO REMAIN IN PLACE UNTIL A COLD
FRONT PASSES EARLY SATURDAY...CONDITIONS WILL CONTINUE TO SUPPORT
MARINE FOG FORMATION. A MARINE FOG ADVISORY HAS BEEN ISSUED...AND
MAY NEED TO BE EXTENDED BEYOND THE CURRENT EXPIRATION TIME OF 7 PM
CDT. GOOD CHANCES OF SHOWERS AND THUNDERSTORMS ARE EXPECTED UNTIL
THIS COLD FRONT MOVES THROUGH THE REGION LATE FRIDAY NIGHT INTO
EARLY SATURDAY. A MODEST OFFSHORE FLOW IS EXPECTED OVER THE
WEEKEND IN THE WAKE OF THE FRONT...WITH SOUTHERLY WINDS RETURNING
TO START THE WORK WEEK.
13
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 78 62 76 49 72 / 30 60 10 10 10
KBPT 77 62 78 52 73 / 30 50 10 10 10
KAEX 80 57 72 44 73 / 30 60 10 10 10
KLFT 79 63 74 49 73 / 30 60 10 10 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...DENSE FOG ADVISORY UNTIL NOON CDT TODAY FOR THE FOLLOWING ZONES:
CALCASIEU LAKE...COASTAL WATERS FROM CAMERON LA TO HIGH
ISLAND TX OUT 20 NM...COASTAL WATERS FROM INTRACOASTAL CITY
TO CAMERON LA OUT 20 NM...COASTAL WATERS FROM LOWER
ATCHAFALAYA RIVER TO INTRACOASTAL CITY LA OUT 20 NM...
SABINE LAKE...VERMILION BAY.
&&
$$
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
638 AM CDT FRI MAR 28 2014
.AVIATION...LIFR AND IFR CEILINGS WILL CONTINUE THROUGH THE MOST
OF THE MORNING ALONG WITH REDUCED VIS IN BR AND -RA. CONDITIONS
WILL GRADUALLY IMPROVE FROM LATE MORNING INTO THE AFTERNOON,
HOWEVER ADDITIONAL RAIN AND THUNDERSTORMS WILL DEVELOP DURING THE
AFTERNOON AND EVENING. THIS WILL REDUCE CEILINGS AND VIS ONCE
AGAIN. RAIN CHANCES WILL DECREASE PAST MIDNIGHT WITH FG DEVELOPING
TOWARD SAT MORNING. WINDS WILL BE SE TO SW TODAY AT 12 KTS OR LESS
OUTSIDE OF STORMS. WINDS MAY BECOME GUSTY AND ERRATIC IN OR NEAR STORMS.
&&
.PREV DISCUSSION... /ISSUED 531 AM CDT FRI MAR 28 2014/
DISCUSSION...
SHOWERS AND THUNDERSTORMS CONTINUE OVER MAINLY EAST CENTRAL
LOUISIANA THIS MORNING...GENERALLY WITHIN AREA OF ENHANCED LOW
LEVEL MSTR INFLUX/CONVERGENCE AND BENEATH DIVERGENCE ALOFT
ENHANCED BY COUPLED JET STRUCTURE BETWEEN SUB-TROPICAL JET AND JET
MAX ASSOCIATED WITH SHORTWAVE TROF LIFTING THROUGH THE UPPER
MIDWEST. UPSTREAM WATER VAPOR IMAGERY CONTINUES TO DEPICT AN
ACTIVE SUB-TROPICAL JET...WITH ANOTHER SHORTWAVE TROF JUST PASSING
EAST OF THE FOUR CORNERS.
THE ONGOING ACTIVITY IS EXPECTED TO GENERALLY SHIFT EASTWARD THIS
MORNING...WITH A GENERAL LULL IN ACTIVITY EXPECTED UNTIL THE APPROACH
OF THIS UPSTREAM SHORTWAVE LATER THIS AFTERNOON. HRRR AND OTHER
MESOSCALE MODELS INDICATE CONVECTION INITIATING OVER CENTRAL/EAST
TEXAS EARLY TO MID AFTERNOON...WITH SUBSEQUENT DOWNSTREAM
MOVEMENT/DEVELOPMENT ACROSS THE FORECAST AREA THIS EVENING. THE MARINE
LAYER MAY PROVE DETRIMENTAL OVER THE COASTAL COUNTIES/PARISHES...BUT
INSTABILITY IS OVERALL PROGGED TO BE GREATER THAN IT WAS ON
THURSDAY...WITH THE ADDITION OF SFC FEATURES...LIKE THE APPROACHING
CDFNT...TO BETTER FOCUS DEVELOPMENT. SPC HAS ENTIRE AREA OUTLINE
IN A SLIGHT RISK...WITH LARGE HAIL/DAMAGING WINDS THE PRIMARY
HAZARDS. LOW LEVEL SHEAR/HELICITY...WHILE NOT PRECLUDING
TORNADOES...SUGGESTS THE RISK IS SUBORDINATE TO THE OTHER TWO.
DECREASING WINDS HAVE SUBSEQUENTLY RESULTED IN DECREASING VSBYS
OVER THE COASTAL WATERS AS WELL AS INLAND. SUFFICIENT TURBULENT
MIXING WILL LIKELY PREVENT INLAND VSBYS FROM REACHING DENSE FOG
CRITERIA...BUT REFER TO THE MARINE DISCUSSION BELOW FOR THE COASTAL
WATERS.
THE CDFNT IS PROGGED TO SWEEP THROUGH THE REGION LATE TONIGHT...WITH
COOLER AND DRIER AIR GIVING WAY TO A PLEASANT WEEKEND. RAIN
CHANCES LOOK TO RETURN FOR THE MID TO LATTER PART OF THE WEEK AMID
THE RETURN OF A WAA REGIME AND ACTIVE SUB-TROPICAL JET.
13
MARINE...
SOUTH WINDS HAVE STEADILY DECREASED EARLY THIS MORNING...WHICH IS
PERMITTING A SLOWER TRANSPORT OF MOISTURE LADEN AIR OVER
RELATIVELY COOLER SHELF WATERS. THE RESULT HAS BEEN A STEADY
DECREASE IN VISIBILITIES SEEN AT OFFSHORE AND COASTAL REPORTING
SITES. WITH THIS PATTERN EXPECTED TO REMAIN IN PLACE UNTIL A COLD
FRONT PASSES EARLY SATURDAY...CONDITIONS WILL CONTINUE TO SUPPORT
MARINE FOG FORMATION. A MARINE FOG ADVISORY HAS BEEN ISSUED...AND
MAY NEED TO BE EXTENDED BEYOND THE CURRENT EXPIRATION TIME OF 7 PM
CDT. GOOD CHANCES OF SHOWERS AND THUNDERSTORMS ARE EXPECTED UNTIL
THIS COLD FRONT MOVES THROUGH THE REGION LATE FRIDAY NIGHT INTO
EARLY SATURDAY. A MODEST OFFSHORE FLOW IS EXPECTED OVER THE
WEEKEND IN THE WAKE OF THE FRONT...WITH SOUTHERLY WINDS RETURNING
TO START THE WORK WEEK.
13
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 77 62 76 49 72 / 30 60 10 10 10
KBPT 79 62 78 52 73 / 30 50 10 10 10
KAEX 78 57 72 44 73 / 40 60 10 10 10
KLFT 78 63 74 49 73 / 50 60 10 10 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...DENSE FOG ADVISORY UNTIL 7 PM CDT THIS EVENING FOR THE FOLLOWING
ZONES: CALCASIEU LAKE...COASTAL WATERS FROM CAMERON LA TO
HIGH ISLAND TX OUT 20 NM...COASTAL WATERS FROM INTRACOASTAL
CITY TO CAMERON LA OUT 20 NM...COASTAL WATERS FROM LOWER
ATCHAFALAYA RIVER TO INTRACOASTAL CITY LA OUT 20 NM...
SABINE LAKE...VERMILION BAY.
&&
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.LAKECHARLES.GOV
WWW.TWITTER.COM/NWSLAKECHARLES
WWW.YOUTUBE.COM/NWSLAKECHARLES
&&
$$
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
531 AM CDT FRI MAR 28 2014
.DISCUSSION...
SHOWERS AND THUNDERSTORMS CONTINUE OVER MAINLY EAST CENTRAL
LOUISIANA THIS MORNING...GENERALLY WITHIN AREA OF ENHANCED LOW
LEVEL MSTR INFLUX/CONVERGENCE AND BENEATH DIVERGENCE ALOFT
ENHANCED BY COUPLED JET STRUCTURE BETWEEN SUB-TROPICAL JET AND JET
MAX ASSOCIATED WITH SHORTWAVE TROF LIFTING THROUGH THE UPPER
MIDWEST. UPSTREAM WATER VAPOR IMAGERY CONTINUES TO DEPICT AN
ACTIVE SUB-TROPICAL JET...WITH ANOTHER SHORTWAVE TROF JUST PASSING
EAST OF THE FOUR CORNERS.
THE ONGOING ACTIVITY IS EXPECTED TO GENERALLY SHIFT EASTWARD THIS
MORNING...WITH A GENERAL LULL IN ACTIVITY EXPECTED UNTIL THE APPROACH
OF THIS UPSTREAM SHORTWAVE LATER THIS AFTERNOON. HRRR AND OTHER
MESOSCALE MODELS INDICATE CONVECTION INITIATING OVER CENTRAL/EAST
TEXAS EARLY TO MID AFTERNOON...WITH SUBSEQUENT DOWNSTREAM
MOVEMENT/DEVELOPMENT ACROSS THE FORECAST AREA THIS EVENING. THE MARINE
LAYER MAY PROVE DETRIMENTAL OVER THE COASTAL COUNTIES/PARISHES...BUT
INSTABILITY IS OVERALL PROGGED TO BE GREATER THAN IT WAS ON
THURSDAY...WITH THE ADDITION OF SFC FEATURES...LIKE THE APPROACHING
CDFNT...TO BETTER FOCUS DEVELOPMENT. SPC HAS ENTIRE AREA OUTLINE
IN A SLIGHT RISK...WITH LARGE HAIL/DAMAGING WINDS THE PRIMARY
HAZARDS. LOW LEVEL SHEAR/HELICITY...WHILE NOT PRECLUDING
TORNADOES...SUGGESTS THE RISK IS SUBORDINATE TO THE OTHER TWO.
DECREASING WINDS HAVE SUBSEQUENTLY RESULTED IN DECREASING VSBYS
OVER THE COASTAL WATERS AS WELL AS INLAND. SUFFICIENT TURBULENT
MIXING WILL LIKELY PREVENT INLAND VSBYS FROM REACHING DENSE FOG
CRITERIA...BUT REFER TO THE MARINE DISCUSSION BELOW FOR THE COASTAL
WATERS.
THE CDFNT IS PROGGED TO SWEEP THROUGH THE REGION LATE TONIGHT...WITH
COOLER AND DRIER AIR GIVING WAY TO A PLEASANT WEEKEND. RAIN
CHANCES LOOK TO RETURN FOR THE MID TO LATTER PART OF THE WEEK AMID
THE RETURN OF A WAA REGIME AND ACTIVE SUB-TROPICAL JET.
13
&&
.MARINE...
SOUTH WINDS HAVE STEADILY DECREASED EARLY THIS MORNING...WHICH IS
PERMITTING A SLOWER TRANSPORT OF MOISTURE LADEN AIR OVER
RELATIVELY COOLER SHELF WATERS. THE RESULT HAS BEEN A STEADY
DECREASE IN VISIBILITIES SEEN AT OFFSHORE AND COASTAL REPORTING
SITES. WITH THIS PATTERN EXPECTED TO REMAIN IN PLACE UNTIL A COLD
FRONT PASSES EARLY SATURDAY...CONDITIONS WILL CONTINUE TO SUPPORT
MARINE FOG FORMATION. A MARINE FOG ADVISORY HAS BEEN ISSUED...AND
MAY NEED TO BE EXTENDED BEYOND THE CURRENT EXPIRATION TIME OF 7 PM
CDT. GOOD CHANCES OF SHOWERS AND THUNDERSTORMS ARE EXPECTED UNTIL
THIS COLD FRONT MOVES THROUGH THE REGION LATE FRIDAY NIGHT INTO
EARLY SATURDAY. A MODEST OFFSHORE FLOW IS EXPECTED OVER THE
WEEKEND IN THE WAKE OF THE FRONT...WITH SOUTHERLY WINDS RETURNING
TO START THE WORK WEEK.
13
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 77 62 76 49 / 30 60 10 10
KBPT 79 62 78 52 / 30 50 10 10
KAEX 78 57 72 44 / 40 60 10 10
KLFT 78 63 74 49 / 50 60 10 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...DENSE FOG ADVISORY UNTIL 7 PM CDT THIS EVENING FOR CALCASIEU
LAKE-COASTAL WATERS FROM CAMERON LA TO HIGH ISLAND TX OUT
20 NM-COASTAL WATERS FROM INTRACOASTAL CITY TO CAMERON LA
OUT 20 NM-COASTAL WATERS FROM LOWER ATCHAFALAYA RIVER TO
INTRACOASTAL CITY LA OUT 20 NM-SABINE LAKE-VERMILION BAY.
&&
$$
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1026 PM EDT SAT MAR 29 2014
.SYNOPSIS...
LOW PRESSURE OVER THE MID ATLANTIC STATES WILL TRACK SLOWLY EAST...
SOUTH OF THE AREA TONIGHT INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH SUNDAY NIGHT/...
945 PM UPDATE: ONLY CHG THIS UPDATE WAS FCST HRLY TEMPS THRU THE
OVRNGT BASED ON 9 PM OBSVD TEMPS. NO CHGS WERE MADE TO FCST OVRNGT
LOWS OR THE REST OF THE NEAR TERM FCST ELEMENTS THIS UPDATE WITH THE
GOING FCST STILL LOOKING TO BE ON TRACK.
725 PM UPDATE: IN THE IMMEDIATE TERM...ADJUSTMENTS WERE MADE TO
OVRNGT CLD CVR AND FCST HRLY TEMPS BASED ON LATEST SAT IMAGERY AND
6 TO 7 PM OBSVD TEMPS. THEN SOME MINOR CHGS WERE MADE TO 6 HRLY
SNFLS SPCLY SUN INTO SUN EVE...SO ACCUMULATIONS REALISTICALLY
MATCHED FCST PRECIP TYPES. THE ONLY SIG CHG WAS A LOWERING OF
SN/PL TOTALS IN THE INTERIOR DOWNEAST WNTR WX ADV AREA AND A NEAR
ELIMINATION OF SN/PL ACCUMULATION MENTION ALG THE IMMEDIATE
DOWNEAST COAST...WHERE PREDOMINATELY NEARLY ALL RN IS FCST FOR
THIS EVENT.
ORGNL DISC: AT THE START OF THE PERIOD THE MAJOR MODELS ARE
SHOWING THE NEXT SYSTEM TO AFFECT OUR AREA CENTERED OVER THE CNTRL
PORTIONS OF THE NC/VA BORDER...WITH A WARM FRONT EXTENDING NORTH
TO THE SW COAST OF MAINE. THE MODEL INDICATE THAT THE LOW IS STILL
DYNAMIC AT THIS POINT...BUT SHOWING THAT THE UPPER LEVEL LOW IS
STARTING TO BECOME VERTICALLY STACKED WITH THE SURFACE LOW...THE
BEGINNING PROCESS OF BECOME COLD CORE. BY MRNG THE LOW MOVES NE TO
THE NJ COAST...PRECIP SPREADS ACROSS ERN MAINE INTO NRN MAINE.
PCPN WILL BE SNOW...WITH SLEET AND FREEZING RAIN MIXED IN ACROSS
THE INTERIOR DOWNEAST AND EAST CNTRL MAINE. AT THIS TIME ALL
MODELS SHOWING A CLOSED LOW AT 500MB AND THE SFC LOW NEARLY
VERTICALLY STACKED. BY THE END OF THE PERIOD...THE BULK OF THE
PCPN MOVES EAST INTO NEW BRUNSWICK...THE LOW DRIFTS NORTH ALONG
THE NJ COAST TO JUST SOUTH OF LONG ISLAND. THE UPPER LOW AND SFC
LOW WILL BE VERTICALLY STACKED. THE GFS...GEM...AND ECMWF SHOW A
NEW LOW IN THE ERN GULF OF MAINE THAT WILL BECOME THE NEW PRIMARY
LOW FOR THIS SYSTEM AS IT TRACKS TOWARD NEW BRUNSWICK.
LOADED THE HRRR MIN TEMP FOR THE OVRNGT...GEM MAX TEMP FOR
TOMORROW. INTERPOLATED FROM MIN TO MAX FOR HRLY TEMPS. USED A
BLEND OF NAM/GFS/GEM/ECMWF FOR HRLY DP/SKY/WND/POP. ADDED 15
PERCENT TO WINDS FOR GUSTS OVER LAND...25 PERCENT OVER WATERS.
LOADED NAWAVE 4 FOR SEAS IN THE COASTAL WATERS.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
A VERTICALLY STACKED SURFACE/UPPER LOW WILL BEGIN TO MOVE SLOWLY
NORTHEAST SUNDAY NIGHT. A NEARLY STATIONARY FRONTAL BOUNDARY WILL
EXTEND NORTHEAST FROM THE SURFACE LOW. ISENTROPIC LIFT AND
OVERRUNNING IN THE VICINITY OF THE FRONT WILL SUPPORT PRECIPITATION
ACROSS THE FORECAST AREA SUNDAY NIGHT. HOWEVER...THE PROXIMITY OF
THE FRONT TO THE COAST REMAINS UNCERTAIN. HAVE BASED THE FORECAST
ON A SLOWER MOVEMENT OF THE SURFACE LOW AND THE FRONT REMAINING
CLOSER TO THE COAST WHICH WILL KEEP MORE EXTENSIVE PRECIPITATION
ACROSS THE FORECAST AREA. HIGH PRESSURE NORTH OF MAINE WILL
CONTINUE TO PROVIDE LOW LEVEL COLD AIR ACROSS THE FORECAST AREA
SUNDAY NIGHT INTO MONDAY. HOWEVER...WARMER AIR ALOFT WILL KEEP A
WINTRY MIX ACROSS MUCH OF THE FORECAST AREA SUNDAY NIGHT. A WINTRY
MIX WILL PERSIST ACROSS NORTHERN AND CENTRAL PORTIONS OF THE
FORECAST AREA SUNDAY NIGHT...WITH RAIN TRANSITIONING TO A WINTRY
MIX ACROSS DOWNEAST AREAS. WINTER STORM WARNINGS WILL REMAIN IN
EFFECT ACROSS NORTHERN AREAS SUNDAY NIGHT...WITH WINTER WEATHER
ADVISORIES ACROSS CENTRAL AREAS AND INTERIOR DOWNEAST PORTIONS OF
THE FORECAST AREA. HAVE HELD WITH THE SLOWER MOVEMENT OF THE
SYSTEM MONDAY...WHICH WILL KEEP LIGHT PRECIPITATION ACROSS THE
FORECAST AREA. ACROSS NORTHERN AREAS EXPECT EXPECT A LIGHT WINTRY
MIX...WITH A WINTRY MIX TRANSITIONING TO RAIN ACROSS CENTRAL AND
DOWNEAST AREAS. THE SURFACE/UPPER LOW WILL MOVE EAST MONDAY NIGHT
WHILE HIGH PRESSURE SLOWLY BUILDS SOUTH WITH DECREASING RAIN/SNOW
SHOWER CHANCES ACROSS THE FORECAST AREA. A SLIGHT CHANCE OF
SHOWERS COULD PERSIST DOWNEAST TUESDAY WITH THE EXITING LOW WHILE
HIGH PRESSURE BUILDS ACROSS NORTHERN MAINE. TEMPERATURES WILL BE
AT SLIGHTLY BELOW NORMAL LEVELS MONDAY/TUESDAY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
LOW PRESSURE WILL BE MOVING AWAY TUESDAY NIGHT AS A RIDGE OF HIGH
PRESSURE BUILDS IN FROM THE WEST. THIS WILL BRING DRY AND RELATIVELY
MILD WEATHER TUESDAY NIGHT INTO WEDNESDAY. A WEAK TROUGH MAY MOVE
THROUGH ON THURSDAY BRINGING SOME CLOUDS AND PERHAPS LIGHT SHOWERS.
OTHERWISE, THE DAY SHOULD REMAIN MOSTLY CLOUDY. HIGH PRESSURE SHOULD
THEN BUILD IN BRINGING DRIER AND SEASONABLY MILD CONDITIONS ON
FRIDAY. GOING INTO THE WEEKEND, LOTS OF UNCERTAINTY REGARDING
WHETHER OR NOT A BLOCKING RIDGE OVER EASTERN CANADA CAN MAINTAIN THE
DRY WEATHER. THE GFS KEEPS CONDITIONS DRY WHILE THE ECMWF BRINGS A
TROUGH OF LOW PRESSURE THROUGH WITH A CHANCE FOR SOME RAIN OR SNOW
SHOWERS. IN THE FORECAST WILL HAVE LOW CHANCE FOR RAIN OR SNOW
SHOWERS NEXT WEEKEND. CURRENTLY DOES NOT LOOK LIKE ANY MAJOR STORMS
ARE EXPECTED THROUGH NEXT WEEKEND, AND TEMPERATURES WILL BE NEAR
NORMAL WHICH WILL BE CONSIDERABLY MILDER THAN THE VERY COLD
CONDITIONS WE HAVE HAD IN MARCH.
&&
.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
NEAR TERM: DETERIORATING CONDITIONS SOUTH TO NORTH AS THE LOW
MOVES INTO THE AREA. MVFR CONDITIONS BHB...ALL OTHER SITES VFR TO
START THE PERIOD THIS EVENING. BY 9PM IFR CONDITIONS BHB IN
RAIN...BGR RAIN BCMG MXD. IFR CONDITIONS MOVE INTO
HUL...PQI...CAR...FVE AFT 3AM...PCPN SNOW BCMG MXD AT HUL TOMORROW
AFTN. IFR CONDITION WILL REMAIN ACROSS THE AREA THROUGH THE END OF
THE PERIOD. PCPN TYPE SN FOR FVE...SN MAY MIX WITH PL BRIEFLY IN
AFTN IN PQI AND CAR.
SHORT TERM: IFR/LIFR CONDITIONS ARE EXPECTED ACROSS THE REGION
SUNDAY NIGHT INTO EARLY MONDAY...WITH MVFR/IFR CONDITIONS LATER
MONDAY. OCCASIONAL MVFR CONDITIONS COULD PERSIST ACROSS THE
REGION MONDAY NIGHT. OCCASIONAL MVFR CONDITIONS COULD PERSIST
ACROSS DOWNEAST AREAS EARLY TUESDAY. OTHERWISE...VFR CONDITIONS
ARE EXPECTED ACROSS THE REGION TUESDAY. VFR CONDITIONS ARE EXPECTED
ACROSS THE REGION WEDNESDAY. VFR CONDITIONS ARE EXPECTED ACROSS
NORTHERN AREAS THURSDAY...WITH OCCASIONAL MVFR CONDITIONS POSSIBLE
DOWNEAST.
&&
.MARINE...
NEAR TERM: 1000 PM UPDATE...WITH NO INTERIM SCA HDLN AND WINDS FCST
TO REACH LOW END GALE FORCE GUSTS IN ABOUT 12 TO 15 HRS...WE
THOUGHT IT BEST TO CONVERT THE GALE WATCH TO A WARNING FOR THE
SAME PD OF TM ADVERTISED IN THE WATCH...NAMELY SUN AFTN THRU
LATE MON NGT...WITH THE 18Z GFS ADVERTISING GALE FORCE WIND GUSTS
FOR APPROXIMATELY THIS TM PD.
ORGNL DISC...THE LOW WILL TRANSIT SLOWLY SOUTH OF OF THE GULF OF
MAINE. TODAYS TRACK IS FARTHER SOUTH THAN WAS PREVIOUS FORECASTED.
WINDS STILL CALL FOR MARGINAL GALE FORCE WINDS FOR TOMORROW. WILL
CONTINUE THE GALE WATCH.
SHORT TERM: MARGINAL GALE CONDITIONS ARE POSSIBLE SUNDAY NIGHT
INTO EARLY MONDAY NIGHT WHICH COULD REQUIRE GALE WARNINGS.
VISIBILITIES WILL BE REDUCED IN RAIN SUNDAY NIGHT INTO EARLY
MONDAY NIGHT...WITH LINGERING RAIN/SNOW SHOWERS POSSIBLE LATER
MONDAY NIGHT INTO TUESDAY.
&&
.HYDROLOGY...
A FLOOD WATCH CONTINUES FOR DOWNEAST MAINE SUNDAY THROUGH MONDAY
AFTERNOON. THE PRECIPITATION ASSOCIATED WITH THE UPCOMING STORM
WILL LIKELY FALL MAINLY AS RAIN OR FREEZING RAIN IN THESE AREAS,
ESPECIALLY ALONG THE COAST. TOTAL LIQUID PRECIPITATION AMOUNTS OF
UP TO 3 INCHES ARE EXPECTED. IN ADDITION TO THIS RAIN...TEMPERATURES
WILL REMAIN NEAR OR ABOVE FREEZING THROUGH SUNDAY ADDING SNOWMELT
TO THE EQUATION. THE SNOWPACK IN THESE AREAS IS HIGHLY VARIABLE,
RANGING FROM AROUND 6 INCHES ALONG THE COAST TO 2 FEET OR MORE IN
THE INTERIOR. THERE IS 2 TO 4 INCHES OF WATER CONTAINED IN THE
PACK ALONG THE COAST WITH 6 TO 8 INCHES FURTHER INLAND. WHILE THE
DEEPER SNOW WILL BE ABLE TO ABSORB SOME OF THE RAIN...MUCH OF IT
WILL BECOME RUNOFF IN ADDITION TO THE SNOWMELT. THIS MEANS
DOWNEAST AREAS COULD POTENTIALLY SEE 4 INCHES OR MORE OF TOTAL
RUNOFF. RIVERS WILL LIKELY RISE SUBSTANTIALLY AND POTENTIALLY
CAUSE RIVER ICE TO BREAK UP...ESPECIALLY IN THOSE PLACES WHERE
THE ICE COMPLETELY FLUSHED OUT IN JANUARY (MEANING THE ICE THERE
NOW IS RELATIVELY WEAK). FOR THOSE RIVER STRETCHES THAT ARE ICE
FREE...ICE COVER UPSTREAM MAY BREAK UP AND COLLECT DOWNSTREAM. IN
ADDITION TO THE POTENTIAL FOR ICE JAMS, THIS AMOUNT OF RAINFALL
AND RUNOFF WILL LIKELY LEAD TO PONDING OF WATER ON ROADWAYS AND
MINOR FLOODING OF LOW-LYING POOR DRAINAGE AREAS. IN ADDITION,
TIDAL LOCATIONS SUCH AS BANGOR WILL HAVE TO BE WATCHED CLOSELY
AROUND THE TIME OF HIGH TIDE. THE CURRENT OFFICIAL NATIONAL
WEATHER SERVICE FORECAST FOR THE PENOBSCOT RIVER AT BANGOR BRINGS
THE GAGE WITHIN 1 FOOT OF FLOOD STAGE WITH HIGH TIDE SUNDAY
MORNING. PERSONS WITH INTERESTS ALONG WATERWAYS OR IN FLOOD-PRONE
LOCATIONS ACROSS HANCOCK...WASHINGTON AND SOUTHERN PENOBSCOT
COUNTIES SHOULD STAY TUNED FOR ADDITIONAL INFORMATION ON THIS
SYSTEM.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...WINTER STORM WARNING FROM 6 AM SUNDAY TO 8 AM EDT MONDAY FOR
MEZ001-002.
WINTER STORM WARNING FROM 2 AM SUNDAY TO 8 AM EDT MONDAY FOR
MEZ003>006-010.
WINTER WEATHER ADVISORY FROM 2 AM SUNDAY TO 8 AM EDT MONDAY
FOR MEZ011-015>017-031-032.
FLOOD WATCH FROM 8 AM EDT SUNDAY THROUGH MONDAY AFTERNOON FOR
MEZ015>017-029-030.
GALE WARNING FROM NOON SUNDAY TO 4 AM EDT TUESDAY FOR MEZ029.
MARINE...GALE WARNING FROM NOON SUNDAY TO 4 AM EDT TUESDAY FOR
ANZ050>052.
&&
$$
NEAR TERM...VJN
SHORT TERM...NORCROSS
LONG TERM...BLOOMER
AVIATION...VJN/NORCROSS
MARINE...VJN/NORCROSS
HYDROLOGY...NORTON
AREA FORECAST DISCUSSION
NWS CARIBOU ME
753 PM EDT SAT MAR 29 2014
.SYNOPSIS...
LOW PRESSURE OVER THE MID ATLANTIC STATES WILL TRACK SLOWLY EAST...
SOUTH OF THE AREA TONIGHT INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH SUNDAY NIGHT/...
725 PM UPDATE: IN THE IMMEDIATE TERM...ADJUSTMENTS WERE MADE TO
OVRNGT CLD CVR AND FCST HRLY TEMPS BASED ON LATEST SAT IMAGERY AND
6 TO 7 PM OBSVD TEMPS. THEN SOME MINOR CHGS WERE MADE TO 6 HRLY
SNFLS SPCLY SUN INTO SUN EVE...SO ACCUMULATIONS REALISTICALLY
MATCHED FCST PRECIP TYPES. THE ONLY SIG CHG WAS A LOWERING OF
SN/PL TOTALS IN THE INTERIOR DOWNEAST WNTR WX ADV AREA AND A NEAR
ELIMINATION OF SN/PL ACCUMULATION MENTION ALG THE IMMEDIATE
DOWNEAST COAST...WHERE PREDOMINATELY NEARLY ALL RN IS FCST FOR
THIS EVENT.
ORGNL DISC: AT THE START OF THE PERIOD THE MAJOR MODELS ARE
SHOWING THE NEXT SYSTEM TO AFFECT OUR AREA CENTERED OVER THE CNTRL
PORTIONS OF THE NC/VA BORDER...WITH A WARM FRONT EXTENDING NORTH
TO THE SW COAST OF MAINE. THE MODEL INDICATE THAT THE LOW IS STILL
DYNAMIC AT THIS POINT...BUT SHOWING THAT THE UPPER LEVEL LOW IS
STARTING TO BECOME VERTICALLY STACKED WITH THE SURFACE LOW...THE
BEGINNING PROCESS OF BECOME COLD CORE. BY MRNG THE LOW MOVES NE TO
THE NJ COAST...PRECIP SPREADS ACROSS ERN MAINE INTO NRN MAINE.
PCPN WILL BE SNOW...WITH SLEET AND FREEZING RAIN MIXED IN ACROSS
THE INTERIOR DOWNEAST AND EAST CNTRL MAINE. AT THIS TIME ALL
MODELS SHOWING A CLOSED LOW AT 500MB AND THE SFC LOW NEARLY
VERTICALLY STACKED. BY THE END OF THE PERIOD...THE BULK OF THE
PCPN MOVES EAST INTO NEW BRUNSWICK...THE LOW DRIFTS NORTH ALONG
THE NJ COAST TO JUST SOUTH OF LONG ISLAND. THE UPPER LOW AND SFC
LOW WILL BE VERTICALLY STACKED. THE GFS...GEM...AND ECMWF SHOW A
NEW LOW IN THE ERN GULF OF MAINE THAT WILL BECOME THE NEW PRIMARY
LOW FOR THIS SYSTEM AS IT TRACKS TOWARD NEW BRUNSWICK.
LOADED THE HRRR MIN TEMP FOR THE OVRNGT...GEM MAX TEMP FOR
TOMORROW. INTERPOLATED FROM MIN TO MAX FOR HRLY TEMPS. USED A
BLEND OF NAM/GFS/GEM/ECMWF FOR HRLY DP/SKY/WND/POP. ADDED 15
PERCENT TO WINDS FOR GUSTS OVER LAND...25 PERCENT OVER WATERS.
LOADED NAWAVE 4 FOR SEAS IN THE COASTAL WATERS.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
A VERTICALLY STACKED SURFACE/UPPER LOW WILL BEGIN TO MOVE SLOWLY
NORTHEAST SUNDAY NIGHT. A NEARLY STATIONARY FRONTAL BOUNDARY WILL
EXTEND NORTHEAST FROM THE SURFACE LOW. ISENTROPIC LIFT AND
OVERRUNNING IN THE VICINITY OF THE FRONT WILL SUPPORT PRECIPITATION
ACROSS THE FORECAST AREA SUNDAY NIGHT. HOWEVER...THE PROXIMITY OF
THE FRONT TO THE COAST REMAINS UNCERTAIN. HAVE BASED THE FORECAST
ON A SLOWER MOVEMENT OF THE SURFACE LOW AND THE FRONT REMAINING
CLOSER TO THE COAST WHICH WILL KEEP MORE EXTENSIVE PRECIPITATION
ACROSS THE FORECAST AREA. HIGH PRESSURE NORTH OF MAINE WILL
CONTINUE TO PROVIDE LOW LEVEL COLD AIR ACROSS THE FORECAST AREA
SUNDAY NIGHT INTO MONDAY. HOWEVER...WARMER AIR ALOFT WILL KEEP A
WINTRY MIX ACROSS MUCH OF THE FORECAST AREA SUNDAY NIGHT. A WINTRY
MIX WILL PERSIST ACROSS NORTHERN AND CENTRAL PORTIONS OF THE
FORECAST AREA SUNDAY NIGHT...WITH RAIN TRANSITIONING TO A WINTRY
MIX ACROSS DOWNEAST AREAS. WINTER STORM WARNINGS WILL REMAIN IN
EFFECT ACROSS NORTHERN AREAS SUNDAY NIGHT...WITH WINTER WEATHER
ADVISORIES ACROSS CENTRAL AREAS AND INTERIOR DOWNEAST PORTIONS OF
THE FORECAST AREA. HAVE HELD WITH THE SLOWER MOVEMENT OF THE
SYSTEM MONDAY...WHICH WILL KEEP LIGHT PRECIPITATION ACROSS THE
FORECAST AREA. ACROSS NORTHERN AREAS EXPECT EXPECT A LIGHT WINTRY
MIX...WITH A WINTRY MIX TRANSITIONING TO RAIN ACROSS CENTRAL AND
DOWNEAST AREAS. THE SURFACE/UPPER LOW WILL MOVE EAST MONDAY NIGHT
WHILE HIGH PRESSURE SLOWLY BUILDS SOUTH WITH DECREASING RAIN/SNOW
SHOWER CHANCES ACROSS THE FORECAST AREA. A SLIGHT CHANCE OF
SHOWERS COULD PERSIST DOWNEAST TUESDAY WITH THE EXITING LOW WHILE
HIGH PRESSURE BUILDS ACROSS NORTHERN MAINE. TEMPERATURES WILL BE
AT SLIGHTLY BELOW NORMAL LEVELS MONDAY/TUESDAY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
LOW PRESSURE WILL BE MOVING AWAY TUESDAY NIGHT AS A RIDGE OF HIGH
PRESSURE BUILDS IN FROM THE WEST. THIS WILL BRING DRY AND RELATIVELY
MILD WEATHER TUESDAY NIGHT INTO WEDNESDAY. A WEAK TROUGH MAY MOVE
THROUGH ON THURSDAY BRINGING SOME CLOUDS AND PERHAPS LIGHT SHOWERS.
OTHERWISE, THE DAY SHOULD REMAIN MOSTLY CLOUDY. HIGH PRESSURE SHOULD
THEN BUILD IN BRINGING DRIER AND SEASONABLY MILD CONDITIONS ON
FRIDAY. GOING INTO THE WEEKEND, LOTS OF UNCERTAINTY REGARDING
WHETHER OR NOT A BLOCKING RIDGE OVER EASTERN CANADA CAN MAINTAIN THE
DRY WEATHER. THE GFS KEEPS CONDITIONS DRY WHILE THE ECMWF BRINGS A
TROUGH OF LOW PRESSURE THROUGH WITH A CHANCE FOR SOME RAIN OR SNOW
SHOWERS. IN THE FORECAST WILL HAVE LOW CHANCE FOR RAIN OR SNOW
SHOWERS NEXT WEEKEND. CURRENTLY DOES NOT LOOK LIKE ANY MAJOR STORMS
ARE EXPECTED THROUGH NEXT WEEKEND, AND TEMPERATURES WILL BE NEAR
NORMAL WHICH WILL BE CONSIDERABLY MILDER THAN THE VERY COLD
CONDITIONS WE HAVE HAD IN MARCH.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
NEAR TERM: DETERIORATING CONDITIONS SOUTH TO NORTH AS THE LOW
MOVES INTO THE AREA. MVFR CONDITIONS BHB...ALL OTHER SITES VFR TO
START THE PERIOD THIS EVENING. BY 9PM IFR CONDITIONS BHB IN
RAIN...BGR RAIN BCMG MXD. IFR CONDITIONS MOVE INTO
HUL...PQI...CAR...FVE AFT 3AM...PCPN SNOW BCMG MXD AT HUL TOMORROW
AFTN. IFR CONDITION WILL REMAIN ACROSS THE AREA THROUGH THE END OF
THE PERIOD. PCPN TYPE SN FOR FVE...SN MAY MIX WITH PL BRIEFLY IN
AFTN IN PQI AND CAR.
SHORT TERM: IFR/LIFR CONDITIONS ARE EXPECTED ACROSS THE REGION
SUNDAY NIGHT INTO EARLY MONDAY...WITH MVFR/IFR CONDITIONS LATER
MONDAY. OCCASIONAL MVFR CONDITIONS COULD PERSIST ACROSS THE
REGION MONDAY NIGHT. OCCASIONAL MVFR CONDITIONS COULD PERSIST
ACROSS DOWNEAST AREAS EARLY TUESDAY. OTHERWISE...VFR CONDITIONS
ARE EXPECTED ACROSS THE REGION TUESDAY. VFR CONDITIONS ARE EXPECTED
ACROSS THE REGION WEDNESDAY. VFR CONDITIONS ARE EXPECTED ACROSS
NORTHERN AREAS THURSDAY...WITH OCCASIONAL MVFR CONDITIONS POSSIBLE
DOWNEAST.
&&
.MARINE...
NEAR TERM: THE LOW WILL TRANSIT SLOWLY SOUTH OF OF THE GULF OF
MAINE. TODAYS TRACK IS FARTHER SOUTH THAN WAS PREVIOUS FORECASTED.
WINDS STILL CALL FOR MARGINAL GALE FORCE WINDS FOR TOMORROW. WILL
CONTINUE THE GALE WATCH.
SHORT TERM: MARGINAL GALE CONDITIONS ARE POSSIBLE SUNDAY NIGHT
INTO EARLY MONDAY NIGHT WHICH COULD REQUIRE GALE WARNINGS.
VISIBILITIES WILL BE REDUCED IN RAIN SUNDAY NIGHT INTO EARLY
MONDAY NIGHT...WITH LINGERING RAIN/SNOW SHOWERS POSSIBLE LATER
MONDAY NIGHT INTO TUESDAY.
&&
.HYDROLOGY...
A FLOOD WATCH CONTINUES FOR DOWNEAST MAINE SUNDAY THROUGH MONDAY
AFTERNOON. THE PRECIPITATION ASSOCIATED WITH THE UPCOMING STORM
WILL LIKELY FALL MAINLY AS RAIN OR FREEZING RAIN IN THESE AREAS,
ESPECIALLY ALONG THE COAST. TOTAL LIQUID PRECIPITATION AMOUNTS OF
UP TO 3 INCHES ARE EXPECTED. IN ADDITION TO THIS RAIN...TEMPERATURES
WILL REMAIN NEAR OR ABOVE FREEZING THROUGH SUNDAY ADDING SNOWMELT
TO THE EQUATION. THE SNOWPACK IN THESE AREAS IS HIGHLY VARIABLE,
RANGING FROM AROUND 6 INCHES ALONG THE COAST TO 2 FEET OR MORE IN
THE INTERIOR. THERE IS 2 TO 4 INCHES OF WATER CONTAINED IN THE
PACK ALONG THE COAST WITH 6 TO 8 INCHES FURTHER INLAND. WHILE THE
DEEPER SNOW WILL BE ABLE TO ABSORB SOME OF THE RAIN...MUCH OF IT
WILL BECOME RUNOFF IN ADDITION TO THE SNOWMELT. THIS MEANS
DOWNEAST AREAS COULD POTENTIALLY SEE 4 INCHES OR MORE OF TOTAL
RUNOFF. RIVERS WILL LIKELY RISE SUBSTANTIALLY AND POTENTIALLY
CAUSE RIVER ICE TO BREAK UP...ESPECIALLY IN THOSE PLACES WHERE
THE ICE COMPLETELY FLUSHED OUT IN JANUARY (MEANING THE ICE THERE
NOW IS RELATIVELY WEAK). FOR THOSE RIVER STRETCHES THAT ARE ICE
FREE...ICE COVER UPSTREAM MAY BREAK UP AND COLLECT DOWNSTREAM. IN
ADDITION TO THE POTENTIAL FOR ICE JAMS, THIS AMOUNT OF RAINFALL
AND RUNOFF WILL LIKELY LEAD TO PONDING OF WATER ON ROADWAYS AND
MINOR FLOODING OF LOW-LYING POOR DRAINAGE AREAS. IN ADDITION,
TIDAL LOCATIONS SUCH AS BANGOR WILL HAVE TO BE WATCHED CLOSELY
AROUND THE TIME OF HIGH TIDE. THE CURRENT OFFICIAL NATIONAL
WEATHER SERVICE FORECAST FOR THE PENOBSCOT RIVER AT BANGOR BRINGS
THE GAGE WITHIN 1 FOOT OF FLOOD STAGE WITH HIGH TIDE SUNDAY
MORNING. PERSONS WITH INTERESTS ALONG WATERWAYS OR IN FLOOD-PRONE
LOCATIONS ACROSS HANCOCK...WASHINGTON AND SOUTHERN PENOBSCOT
COUNTIES SHOULD STAY TUNED FOR ADDITIONAL INFORMATION ON THIS
SYSTEM.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...WINTER STORM WARNING FROM 6 AM SUNDAY TO 8 AM EDT MONDAY FOR
MEZ001-002.
WINTER STORM WARNING FROM 2 AM SUNDAY TO 8 AM EDT MONDAY FOR
MEZ003>006-010.
WINTER WEATHER ADVISORY FROM 2 AM SUNDAY TO 8 AM EDT MONDAY
FOR MEZ011-015>017-031-032.
FLOOD WATCH FROM SUNDAY MORNING THROUGH MONDAY AFTERNOON FOR
MEZ015>017-029-030.
MARINE...GALE WATCH FROM SUNDAY AFTERNOON THROUGH LATE MONDAY NIGHT FOR
ANZ050>052.
&&
$$
NEAR TERM...NORTON/VJN
SHORT TERM...NORCROSS
LONG TERM...BLOOMER
AVIATION...NORTON/VJN/NORCROSS
MARINE...NORTON/VJN/NORCROSS
HYDROLOGY...NORTON
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
926 PM CDT Sat Mar 29 2014
.UPDATE:
Issued at 919 PM CDT Sat Mar 29 2014
Area of MVFR stratus has continued to dissipate and is now
confined to portions of south-central Illinois. Expect this area
to completely erode by 0600 UTC with mainly clear skies for most
of the rest of tonight. Exception would be over western areas as
cirrus tries to advect in from the west/northwest.
Surface temperatures over the past two hours have dropped very
rapidly over most of the region where combination of clear
skies/light winds exist. Lowered minimum temperatures a few
degrees over many areas using a blend of the 0000 UTC RAP which
was capturing this rapid drop fairly well as well as the previous
forecast. Other concern overnight will be fog potential and patchy
fog with restricted visibilities below 3 miles still looks on
track though certainly could not rule out some denser fog
especially in river valleys and other low-lying elevations.
Gosselin
&&
.SHORT TERM: (Through Late Tonight)
Issued at 320 PM CDT Sat Mar 29 2014
Pesky stratus seems to be both clearing and eroding at a snails
pace this afternoon and has a done number on the temperatures.
Present indications based on satellite trends and the RAP which
has handled the low clouds best, is that areas generally along and
east of the MS River will see clouds into early evening with
clearing from mid-late evening. Otherwise the expansive NE-SW high
pressure system currently extending from WI into TX will slide
east across the region tonight with the axis centered thru SE MO
and southern IL at 12z. The slow clearing trend of the clouds
along with light winds overnight across the SE third of the CWA
has prompted me to add a mention of fog overnight.
Glass
.LONG TERM: (Sunday through Next Saturday)
Issued at 320 PM CDT Sat Mar 29 2014
It finally looks like the warm-up will commence on Sunday. Heights
aloft that begin rising tonight in the wake of the departing upper
trof, will continue to rise on Sunday while the surface high
retreats and low level southerly flow and warm advection get
underway. There should be no low clouds to deal with a just some
thin high clouds filtering across the region. The current forecast
leveraging the warmer temperatures looks right on the mark and no
changes were made. The warmer temps combined with low afternoon
RH values and increasing southerly winds support an elevated fire
danger threat across central and east central MO, which will be
highlighted in the HWO.
Continued southerly low level flow on Sunday night will lead to
"milder" min temperatures and a slow return in low level moisture.
The aforementioned expansive surface high and its southern extent
will initially have a profounded effect on trajectories and delay
quality moisture return. However mid level moisture won`t be an
issue and this along with the eastern edge of steeper mid level
lapse rates spreads into central MO just before daybreak on
Monday. These ingredients along with the leading edge of forcing
aloft associated with an upstream trof, suggests potential for
some high-based scattered showers/thunderstorms and hence have
added some slight chance pops.
The week ahead looks especially active. The migratory upper trof
partly responsible for the slight chance pops late Sunday night
will move across the region Monday afternoon and early evening
spreading height falls and cooling aloft along with a plume of
steep mid level lapse rates. This combined with a gradual increase
in low level moisture and forcing should be sufficient for
scattered elevated showers/thunderstorms within the warm sector, moving
through central and northeast MO during the morning gradually
dwindling in coverage during the afternoon as they move east. By
the time the cold front moves through the area Monday night,
forcing aloft appears to have outrun the front and boundary layer
moisture and hence instability are quite weak. I suspect anything
that might be able to develop with be quite spotty and just have a
slight chance pop.
The most active period will be late Tuesday night into Thursday.
The front that moves through Monday night will move back north
and waver across the region. The warm sector air mass south of
this boundary will become quite unstable thanks to continued
northward return of quality Gulf moisture and the presence of
steep mid level lapse rates, and with a strong low level jet
evolving there will be good elevated instability and forcing north
this boundary. The models differ quite a bit on the position of
the next formidable migratory upper trof and the position of
attendant surface low(s) and this boundary. While all the guidance
supports a stormy period, the more northern position which has
been consistently advertised by the ECMWF would lead to a much
more volatile set-up.
Glass
&&
.AVIATION: (For the 00z TAFs through 00z Sunday Evening)
Issued at 546 PM CDT Sat Mar 29 2014
Specifics for KCOU: Although light fog is possible tonight across
the region, KCOU experienced sufficient daytime mixing to limit
the overnight fog potential. Winds start to increase by 12z due to
the tightening pressure gradient between a surface high to the
southeast and a developing low to the northwest.
Specifics for KSTL, KSUS, KCPS, KUIN: Stratus was slow to clear
today and nearly clear skies with light winds are expected
overnight. The combination of limited daytime mixing and good
radiational cooling conditions will probably lead to light fog
formation, especially near and east of the Mississippi River.
Winds start to increase by 12z due to the tightening pressure
gradient between a surface high to the southeast and a developing
low to the northwest.
Kanofsky
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
257 AM CDT Fri Mar 28 2014
.SHORT TERM: (Through Sunday)
Issued at 255 AM CDT Fri Mar 28 2014
Surface low moving northeast across Lake Michigan this morning with
the trailing cold front about to exit the eastern CWA. Large area of
"wrap around" clouds affecting the northern half of the CWA this
morning will continue to move east and scatter with strong late
March insolation. Clouds will be on the increase again by this
afternoon as the next shortwave trof currently crossing the Rockies
digs toward the Midwest. Model guidance in good agreement that
surface low pressure will develop in eastern TX and move northeast
into TN by Saturday morning. Deepening mid/upper level trof will
cause rain to develop and increase from the southwest late this
afternoon, covering the southeastern half of the CWA this evening.
Greatest QPF (as much as a half inch) look to remain across the
eastern Ozarks, southeast MO and southern IL, with lighter amounts
of a tenth of an inch or less up to St. Louis and south central IL.
Trof will quickly move east of the area by Saturday morning with
seasonal temperatures and dry conditions expected as a surface ridge
builds into the Middle Mississippi River Valley from the Plains.
500mb heights quickly rise and return surface flow ensues on Sunday
in the wake of the surface ridge. Temperatures expected to jump well
above normal and have forecast highs a few degrees above the warmest
guidance given favorable synoptic pattern.
CVKING
.LONG TERM: (Sunday Night through Thursday)
Issued at 255 AM CDT Fri Mar 28 2014
Active weather pattern expected next week with a cold front moving
across the region on Sunday night/Monday morning providing a chance
of showers, with a larger synoptic system affecting the region
Tuesday night through at least Thursday morning. Temperatures will
be cooler than average in the wake of the cold front on Tuesday, but
moderation is expected as early as Wednesday as a warm front is
advertised to develop and move north into the Midwest. Models
advertising some healthy QPF with this system, which is welcome news
given the 3 month precipitation deficits.
CVKING
&&
.AVIATION: (For the 06z TAFs through 06z Friday Night)
Issued at 1147 PM CDT Thu Mar 27 2014
Convection over southeast sections of the CWA will continue to
move away from the TAF sites, and primary overnight concern deals
with SC and associated MVFR cigs (2-3kft) that are rotating
across the northern half of Missouri in the wake of the cold
front. Earlier RAP runs appear to have the best handle on this low
level moisture, which has now made it as far south as COU, and
should work into the STL metro area over the next few hours. Then
expect cloud deck to gradually clear/dissipate from SW to NE
across the CWA in the 12-16z time frame due to combination of low
level drying, diurnal heating, and loss of cyclonic curvature.
Approach of next shortwave should mean thickening mid clouds by
early tomorrow evening, with a few showers threatening the STL
metro late in the period.
Specifics for KSTL: As mentioned above, MVFR cigs (2-3kft) that have
dropped into mid MO should arrive in the STL area over the next
few hours and linger into early tomorrow morning. Forecast
soundings then suggest a gradual clearing trend by mid morning
which will cause the low cloud deck to scatter out. Mid level
cloud deck in advance of the next system will begin increasing by
late afternoon, with a few showers moving into the area in the
03-06z time frame.
Truett
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 57 41 57 38 / 5 80 5 0
Quincy 51 35 54 36 / 5 10 5 0
Columbia 54 36 59 38 / 10 20 5 0
Jefferson City 56 36 59 37 / 10 20 5 0
Salem 56 40 55 34 / 5 80 10 0
Farmington 61 40 59 35 / 20 80 5 0
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1203 AM CDT Fri Mar 28 2014
.SHORT TERM: (Through Late Tonight)
Issued at 306 PM CDT Thu Mar 27 2014
A dynamic low pressure system will push rapidly across our
forecast area late this afternoon and this evening. Wind shear
params are quite favorable for strong to severe storms. However,
instability params are currently not as favorable as indicated by
the 18z SGF sounding. It shows a strong mid-level cap (CIN 315
J/kg) and lower instability available without much additional
surface heating.
Some clearing is developing about and hour or two before the line
of storms arrives, per satellite and radar loops. We will continue to
expect a line of convection to race through the area starting
between 4 and 5 pm for our western counties and reaching our
eastern counties by 10 or 11 pm. The primary hazards will be large
hail and damaging winds, especially the cap erodes sufficiently
for uninhibited updrafts.
Behind the line of storms and cold fropa, we should see some
clearing develop from west to east after midnight as steady NW
winds bring colder are to the region.
Shimon
.LONG TERM: (Friday through Next Thursday)
Issued at 306 PM CDT Thu Mar 27 2014
Despite some sunshine on Friday the mixing of 850mb temps in the
2C to 8C range will keep highs around 50 north with around 60
south. Increasing clouds in the afternoon will indicate the
approach of the next low pressure system. That shortwave is
forecast to track just south of Missouri and Illinois, with
varying solutions in the 12z models as to how far north the
precipitation shield will extend Friday evening. The GFS and
Canadian GEM continue to be the most aggressive with the
northern extent, covering a majority of the LSX forecast area,
while the NAM and ECMWF just affect the southeastern third of the
area. We confined likely PoPs in th evening to the southeastern
areas where the best forcing for precip will most likely reside,
with chance PoPs in all but the NW third. After midnight Friday
night, the wave will quickly slide to the east and dry air will
help to limit the northern extent to areas southeast of St Louis.
Dry and cool conditions will return for Saturday as sunshine
prevails for much of the day. Surface ridging and steady height
rises aloft on Sunday will produce a noticeable warming trend, as
highs climb into the mid 60s to around 70. The mild conditions
will extend into Monday but precipitation chances will increase
Monday morning ahead of a cold front. Low pressure will track from
eastern Colorado to Iowa on Monday, as its trailing cold front
reaches western Missouri by 00z/7pm Monday. Moisture will be
limited this far south of the system, so precip coverage only
warranted chance PoPs for now. A few light showers may linger in
western Illinois Monday night, but most areas should see dry
conditions overnight.
The next in a long series of weather systems is projected to
arrive in the area late Tuesday night or Wednesday, as a warm
frontogenesis develops across our forecast area from SW to NE. Per
the GFS, low pressure will eventually track NE along that front
later Wed into Wed evening, increasing precip chances into the
likely category in the NW Wed afternoon and the SE Wed night.
Timing differences in the extended have prompted the inclusion of
chance PoPs as late as Thursday due to the ECMWF indicating a
delayed passage of low pressure along the front.
Shimon
&&
.AVIATION: (For the 06z TAFs through 06z Friday Night)
Issued at 1147 PM CDT Thu Mar 27 2014
Convection over southeast sections of the CWA will continue to
move away from the TAF sites, and primary overnight concern deals
with SC and associated MVFR cigs (2-3kft) that are rotating
across the northern half of Missouri in the wake of the cold
front. Earlier RAP runs appear to have the best handle on this low
level moisture, which has now made it as far south as COU, and
should work into the STL metro area over the next few hours. Then
expect cloud deck to gradually clear/dissipate from SW to NE
across the CWA in the 12-16z time frame due to combination of low
level drying, diurnal heating, and loss of cyclonic curvature.
Approach of next shortwave should mean thickening mid clouds by
early tomorrow evening, with a few showers threatening the STL
metro late in the period.
Specifics for KSTL: As mentioned above, MVFR cigs (2-3kft) that have
dropped into mid MO should arrive in the STL area over the next
few hours and linger into early tomorrow morning. Forecast
soundings then suggest a gradual clearing trend by mid morning
which will cause the low cloud deck to scatter out. Mid level
cloud deck in advance of the next system will begin increasing by
late afternoon, with a few showers moving into the area in the
03-06z time frame.
Truett
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1211 PM CDT FRI MAR 28 2014
.UPDATE...
ISSUED AT 1116 AM CDT FRI MAR 28 2014
MADE SOME ADJUSTMENTS TO THE FORECAST TODAY...ADDING IN A CHANCE
OF SPRINKLES ACROSS SOUTHEAST NEBRASKA. VERY SUBTLE DISTURBANCE ON
WATER VAPOR MOVING OUT OF NORTH CENTRAL KANSAS COULD GENERATE SOME
PRECIP ALONG THE NE/KS BORDER REGION THIS MORNING. ALSO DROPPED
TEMPS THERE JUST A BIT DUE TO INCREASED CLOUD COVER. COULD ALSO BE
A FLURRY IN EXTREME NORTHEAST NEBRASKA...BUT BELIEVE ECHOES ARE
PROBABLY ALOFT THERE. HOWEVER...SLIGHT PRECIP CHANCES TUCKED IN
WITH THE UPPER TROUGH...CURRENTLY MOVING THROUGH CENTRAL SOUTH
DAKOTA...COULD MOVE INTO NORTHEAST NEBRASKA LATER THIS AFTERNOON
AND LINGER FOR AN HOUR OR TWO EARLY THIS EVENING...MORE IN LINE
WITH LATEST RAP SUGGESTION. ALSO DROPPED TEMPS IN NORTHEAST
NEBRASKA DUE TO THE POOR MIXING AND CLOUD COVER.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 304 AM CDT FRI MAR 28 2014
THE SHORTWAVE TROUGH THAT BROUGHT THE WEATHER TO THE AREA ON
THURSDAY IS MOVING THROUGH THE MID MS RIVER VALLEY EARLY THIS
MORNING. ON THE HEELS OF THIS SYSTEM EARLY MORNING WATER VAPOR
IMAGERY INDICATED ANOTHER SHORTWAVE TROUGH OVER THE HIGH PLAINS.
REGIONAL RADAR MOSAIC INDICATES THAT SCT LIGHT PRECIP ASSOCIATED
WITH THIS SYSTEM EXTENDS FROM SW SD INTO WRN KS. MODELS ARE
CONSISTENT IN TAKING THIS SHORTWAVE TROUGH EAST TODAY ACROSS THE
FA. LARGE-SCALE FORCING FOR ASCENT DOES INCREASE THROUGH THE DAY
AS THE BETTER 500 TO 300 MB Q-VECTOR CONVERGENCES MOVES THROUGH.
THE SYSTEM WILL BE MOVING INTO A DRY ATMOSPHERE WITH INCREASING
STATIC STABILITY THOUGH...WHICH IS EXPECTED TO SIGNIFICANTLY LIMIT
THE IMPACT TO THE SENSIBLE WEATHER FOR EASTERN NEB/WESTERN IA. WE
WILL SEE PERIODS OF CLOUDS TODAY /INITIALLY A WAA BAND THIS
MORNING FOLLOWED BY SOME POSSIBLE SUNSHINE AND MORE CLOUDS
ASSOCIATED WITH THE DPVA LATE THIS AFTERNOON/. WE HAVE CONFINED
THE AREAL EXTENT OF THE PRECIP TO OUR FAR NORTHWEST COUNTIES AND
WE WOULDN`T BE SURPRISED IF OUR ENTIRE AREA STAYS DRY TODAY. WITH
SOME PARTIAL SUNSHINE EXPECTED TODAY WE DID INCREASE HIGHS A TOUCH
ALONG AND SOUTH OF I80.
THE SURFACE RIDGE IN THE WAKE OF THIS SHORTWAVE TROUGH WILL CROSS
THE FA TONIGHT AND WITH SKIES CLEARING...WINDS BECOMING LIGHT AND
VARIABLE...AND RECENT RAIN WE LEFT IN THE FOG MENTION FOR FRI
NIGHT. RETURN FLOW WILL START LATE FRIDAY NIGHT INTO THE DAY ON
SATURDAY WITH SOUTHERLY WINDS INCREASING. WITH FULL SUNSHINE AND A
DRY GROUND WE SHOULD SEE DECENT MIXING WITH HIGHS IN THE 60S IN
ERN NEB AND UPPER 50S WRN IA. AS THE NEXT SHORTWAVE TROUGH MOVES
INTO THE ROCKIES SAT NIGHT SURFACE CYCLOGENESIS WILL INCREASE OVER
THE HIGH PLAINS LEADING TO A BREEZY AND MILD NIGHT FOR THE FA.
WITH MILD OVERNIGHT TEMPS ON SAT NIGHT THIS SHOULD SET THE STAGE
FOR A WARM AND WINDY SUN. MODELS INDICATE MID LEVEL LAPSE RATES OF
7.5 TO 8.5 C/KM ON SAT NIGHT AND HINT AT SOME MOISTURE IN THIS
LAYER AS WELL. THIS COULD LEAD TO SOME ACCAS SAT NIGHT INTO
SUNDAY BUT ATTM DOESN`T APPEAR THAT THIS WOULD NEGATIVELY AFFECT
HIGHS ON SUNDAY WITH 70S LIKELY SOUTH OF THE WARM FRONT AND AHEAD
OF THE COLD FRONT.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 304 AM CDT FRI MAR 28 2014
THE SHORTWAVE TROUGH IN THE SHORT TERM WILL EJECT NEWD ON SUNDAY
NIGHT WITH A SURFACE LOW CROSSING NEB OVERNIGHT. THE MODELS ARE
VERY CONSISTENT IN DEVELOPING A STRONG LOW-LEVEL JET ON SUNDAY
NIGHT ACROSS KS INTO NEB/IA. THE NAM HAS MUCH HIGHER H85 DEWPOINTS
AND APPEARS TO BE AN OUTLIER COMPARED TO THE EC/GFS. THE NAM/SREF
DEVELOPS SOME CONVECTIVE PRECIP...BUT POINT FORECAST SOUNDINGS
FROM THE NAM/SREF ARE STRONGLY CAPPED ON SUNDAY NIGHT EVEN WITH
THE HIGHER MOISTURE PROFILE. WE MAY SEE A FEW SHOWERS ABOVE THE
CAP OVER THE EASTERN 2/3RD OF THE FA AND WILL MAINTAIN SOME SCHC
POPS FOR THIS POSSIBILITY. THE SURFACE COLD FRONT WILL BE MOVING
THROUGH THE FA ON MONDAY WITH THE DEFORMATION ZONE MOVING ACROSS
SD/MN. SOME OF THIS MAY CLIP NE NEB AND WILL CONT WITH SOME CHC
POPS THERE DURING THE DAY.
THE PERIOD MONDAY NIGHT THROUGH TUES LOOKS QUIET AND DRY BEFORE
THE NEXT SHORTWAVE TROUGH MOVES INTO THE CENTRAL PLAINS. THE
EC/GFS HAVE STRONG DIFFERENCES IN THE TIMING AND TRACK OF THIS
SYSTEM...BUT CHC POPS FOR SOME RA APPEAR WARRANTED DURING THIS
PERIOD. WE WILL INCLUDE SOME CHC OF RA/SN IN THE NW DURING THE
OVERNIGHT PERIODS. OTHERWISE BELOW NORMAL TEMPERATURES ARE
EXPECTED FOR THE EXTENDED PERIOD OF THE FORECAST.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1209 PM CDT FRI MAR 28 2014
MVFR CEILINGS AT KOMA WERE BEGINNING TO MOVE BACK EAST BASED ON
RECENT SATELLITE IMAGERY AND WILL PROBABLY GO BACK TO VFR BY 20Z
AT THAT LOCATION. OTHERWISE...VFR CONDITIONS PREVAIL THROUGH THE
PERIOD WITH LIGHT WINDS GENERALLY LESS THAN 7 KNOTS. WINDS DO
BECOME SOUTH ON SATURDAY...AND COULD APPROACH 12 KNOTS AT KOFK BY
16Z...BUT NOT UNTIL AFTER THE END OF THE TAF PERIOD AT BOTH
KLNK/KOMA.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
UPDATE...DEWALD
SHORT TERM...BOUSTEAD
LONG TERM...BOUSTEAD
AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1121 AM CDT FRI MAR 28 2014
.UPDATE...
ISSUED AT 1116 AM CDT FRI MAR 28 2014
MADE SOME ADJUSTMENTS TO THE FORECAST TODAY...ADDING IN A CHANCE
OF SPRINKLES ACROSS SOUTHEAST NEBRASKA. VERY SUBTLE DISTURBANCE ON
WATER VAPOR MOVING OUT OF NORTH CENTRAL KANSAS COULD GENERATE SOME
PRECIP ALONG THE NE/KS BORDER REGION THIS MORNING. ALSO DROPPED
TEMPS THERE JUST A BIT DUE TO INCREASED CLOUD COVER. COULD ALSO BE
A FLURRY IN EXTREME NORTHEAST NEBRASKA...BUT BELIEVE ECHOES ARE
PROBABLY ALOFT THERE. HOWEVER...SLIGHT PRECIP CHANCES TUCKED IN
WITH THE UPPER TROUGH...CURRENTLY MOVING THROUGH CENTRAL SOUTH
DAKOTA...COULD MOVE INTO NORTHEAST NEBRASKA LATER THIS AFTERNOON
AND LINGER FOR AN HOUR OR TWO EARLY THIS EVENING...MORE IN LINE
WITH LATEST RAP SUGGESTION. ALSO DROPPED TEMPS IN NORTHEAST
NEBRASKA DUE TO THE POOR MIXING AND CLOUD COVER.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 304 AM CDT FRI MAR 28 2014
THE SHORTWAVE TROUGH THAT BROUGHT THE WEATHER TO THE AREA ON
THURSDAY IS MOVING THROUGH THE MID MS RIVER VALLEY EARLY THIS
MORNING. ON THE HEELS OF THIS SYSTEM EARLY MORNING WATER VAPOR
IMAGERY INDICATED ANOTHER SHORTWAVE TROUGH OVER THE HIGH PLAINS.
REGIONAL RADAR MOSAIC INDICATES THAT SCT LIGHT PRECIP ASSOCIATED
WITH THIS SYSTEM EXTENDS FROM SW SD INTO WRN KS. MODELS ARE
CONSISTENT IN TAKING THIS SHORTWAVE TROUGH EAST TODAY ACROSS THE
FA. LARGE-SCALE FORCING FOR ASCENT DOES INCREASE THROUGH THE DAY
AS THE BETTER 500 TO 300 MB Q-VECTOR CONVERGENCES MOVES THROUGH.
THE SYSTEM WILL BE MOVING INTO A DRY ATMOSPHERE WITH INCREASING
STATIC STABILITY THOUGH...WHICH IS EXPECTED TO SIGNIFICANTLY LIMIT
THE IMPACT TO THE SENSIBLE WEATHER FOR EASTERN NEB/WESTERN IA. WE
WILL SEE PERIODS OF CLOUDS TODAY /INITIALLY A WAA BAND THIS
MORNING FOLLOWED BY SOME POSSIBLE SUNSHINE AND MORE CLOUDS
ASSOCIATED WITH THE DPVA LATE THIS AFTERNOON/. WE HAVE CONFINED
THE AREAL EXTENT OF THE PRECIP TO OUR FAR NORTHWEST COUNTIES AND
WE WOULDN`T BE SURPRISED IF OUR ENTIRE AREA STAYS DRY TODAY. WITH
SOME PARTIAL SUNSHINE EXPECTED TODAY WE DID INCREASE HIGHS A TOUCH
ALONG AND SOUTH OF I80.
THE SURFACE RIDGE IN THE WAKE OF THIS SHORTWAVE TROUGH WILL CROSS
THE FA TONIGHT AND WITH SKIES CLEARING...WINDS BECOMING LIGHT AND
VARIABLE...AND RECENT RAIN WE LEFT IN THE FOG MENTION FOR FRI
NIGHT. RETURN FLOW WILL START LATE FRIDAY NIGHT INTO THE DAY ON
SATURDAY WITH SOUTHERLY WINDS INCREASING. WITH FULL SUNSHINE AND A
DRY GROUND WE SHOULD SEE DECENT MIXING WITH HIGHS IN THE 60S IN
ERN NEB AND UPPER 50S WRN IA. AS THE NEXT SHORTWAVE TROUGH MOVES
INTO THE ROCKIES SAT NIGHT SURFACE CYCLOGENESIS WILL INCREASE OVER
THE HIGH PLAINS LEADING TO A BREEZY AND MILD NIGHT FOR THE FA.
WITH MILD OVERNIGHT TEMPS ON SAT NIGHT THIS SHOULD SET THE STAGE
FOR A WARM AND WINDY SUN. MODELS INDICATE MID LEVEL LAPSE RATES OF
7.5 TO 8.5 C/KM ON SAT NIGHT AND HINT AT SOME MOISTURE IN THIS
LAYER AS WELL. THIS COULD LEAD TO SOME ACCAS SAT NIGHT INTO
SUNDAY BUT ATTM DOESN`T APPEAR THAT THIS WOULD NEGATIVELY AFFECT
HIGHS ON SUNDAY WITH 70S LIKELY SOUTH OF THE WARM FRONT AND AHEAD
OF THE COLD FRONT.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 304 AM CDT FRI MAR 28 2014
THE SHORTWAVE TROUGH IN THE SHORT TERM WILL EJECT NEWD ON SUNDAY
NIGHT WITH A SURFACE LOW CROSSING NEB OVERNIGHT. THE MODELS ARE
VERY CONSISTENT IN DEVELOPING A STRONG LOW-LEVEL JET ON SUNDAY
NIGHT ACROSS KS INTO NEB/IA. THE NAM HAS MUCH HIGHER H85 DEWPOINTS
AND APPEARS TO BE AN OUTLIER COMPARED TO THE EC/GFS. THE NAM/SREF
DEVELOPS SOME CONVECTIVE PRECIP...BUT POINT FORECAST SOUNDINGS
FROM THE NAM/SREF ARE STRONGLY CAPPED ON SUNDAY NIGHT EVEN WITH
THE HIGHER MOISTURE PROFILE. WE MAY SEE A FEW SHOWERS ABOVE THE
CAP OVER THE EASTERN 2/3RD OF THE FA AND WILL MAINTAIN SOME SCHC
POPS FOR THIS POSSIBILITY. THE SURFACE COLD FRONT WILL BE MOVING
THROUGH THE FA ON MONDAY WITH THE DEFORMATION ZONE MOVING ACROSS
SD/MN. SOME OF THIS MAY CLIP NE NEB AND WILL CONT WITH SOME CHC
POPS THERE DURING THE DAY.
THE PERIOD MONDAY NIGHT THROUGH TUES LOOKS QUIET AND DRY BEFORE
THE NEXT SHORTWAVE TROUGH MOVES INTO THE CENTRAL PLAINS. THE
EC/GFS HAVE STRONG DIFFERENCES IN THE TIMING AND TRACK OF THIS
SYSTEM...BUT CHC POPS FOR SOME RA APPEAR WARRANTED DURING THIS
PERIOD. WE WILL INCLUDE SOME CHC OF RA/SN IN THE NW DURING THE
OVERNIGHT PERIODS. OTHERWISE BELOW NORMAL TEMPERATURES ARE
EXPECTED FOR THE EXTENDED PERIOD OF THE FORECAST.
&&
.AVIATION...(12Z TAFS FOR KOFK...KLNK...AND KOMA.)
ISSUED AT 607 AM CDT FRI MAR 28 2014
LIGHT AND VARIABLE WINDS ARE EXPECTED THROUGH THE TAF PERIOD. BANK
OF MVFR STRATUS IS PUSHING WESTWARD TOWARD KOMA...AND WILL LIKELY
IMPACT THE TAF SITE FOR MUCH OF THE MORNING...WITH VFR CONDITIONS
EXPECTED AFTER IT CLEARS AROUND MIDDAY AS MID-LEVEL CEILINGS
EVENTUALLY GIVE WAY TO CLEARING TONIGHT. AT KOFK...VFR CONDITIONS
ARE LIKELY THROUGH TODAY...WITH SOME PERIOD OF LOW-END VFR
CEILINGS POSSIBLE THIS AFTERNOON. AT KLNK...VFR CEILINGS ARE
EXPECTED TODAY...WITH CLEARING SKIES TONIGHT.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
UPDATE...DEWALD
SHORT TERM...BOUSTEAD
LONG TERM...BOUSTEAD
AVIATION...MAYES
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
633 AM CDT FRI MAR 28 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 347 AM CDT FRI MAR 28 2014
THE UPPER LEVEL LOW ACROSS NERN WY APPEARS TO BE DRIFTING EAST
SOUTHEAST WHICH WOULD CARRY IT INTO NRN NEBRASKA THIS AFTERNOON. A
WARM FRONT IS EXPECTED TO LIFT NORTH AHEAD OF THE LOW PUSHING
TEMPERATURES INTO THE UPPER 50S ACROSS SWRN NEB WHILE THE FAR
NORTHEAST REMAINS IN THE UPPER 30S. THE RAP...GEM REGIONAL AND NAM
CONTINUE ISOLATED TO SCATTERED SNOW SHOWERS ALONG THE FRONT WHICH
TRANSITIONS TO RAIN SHOWERS THIS AFTN SOUTH OF THE FRONT. VERY
LITTLE QPF IS EXPECTED...0.05 INCHES OR LESS WITH THIS SYSTEM BUT
THIS COULD BE UNDERDONE GIVEN THE MODELS MAY BE USING RADAR AS A QPF
GUIDE AND THERE IS NO RADAR COVERAGE ACROSS NERN WY.
SO POPS ARE ISOLATED TO SCATTERED AND A WAIT AND SEE APPROACH IS IN
PLACE UNTIL THE SYSTEMS CLEARS THE BLACK HILLS. OBSERVATION SITES IN
NORTHEAST WYOMING HAVE DROPPED BELOW 1 MILE AT TIMES IN THE SNOW SO
THERE MAY AN OPPORTUNITY FOR HIGHER QPF THAN SHOWN BY THESE MODELS.
THE ECM DOES NOT PRODUCE VERY HIGH QPF EITHER.
THIS SYSTEM EXITS THE FCST AREA THIS EVENING AND IN DOING SO TUGS
ANOTHER WEAK AREA OF ARCTIC HIGH PRESSURE INTO THE FCST AREA
OVERNIGHT. LOWS IN THE 20S ARE EXPECTED TONIGHT AND WE SHOULD SEE A
WARM FRONT LIFTING THROUGH WRN NEB AFTER MIDNIGHT SETTING THINGS UP
FOR A WARM DAY ON SATURDAY.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 347 AM CDT FRI MAR 28 2014
A TRANSIENT LOW AMPLITUDE RIDGE WILL BUILD ACROSS THE
CENTRAL/NORTHERN PLAINS THIS WEEKEND...BUT THEN BREAK DOWN LATE
SUNDAY WITH THE APPROACH OF A SOUTH-CENTRAL ROCKIES SHORTWAVE
TROUGH. AT THE SURFACE...A LEE TROUGH OVER THE HIGH PLAINS WILL
DEVELOP SATURDAY IN ADVANCE OF THE APPROACHING UPPER TROUGH. THIS
WILL ALLOW FOR A INCREASING PRESSURE GRADIENT ACROSS CENTRAL
NEBRASKA AS HIGH PRESSURE REMAINS IN THE VICINITY OF THE GREAT
LAKES. TEMPERATURES WILL SOAR IN ADVANCE OF THE LEE SFC TROUGH AS
A DOWNSLOPING SOUTHWESTERLY COMPONENT OF THE LOWER TROPOSPHERIC
WIND COMBINES WITH A FULL LATE MARCH SUN. HIGHS WILL REACH WELL
INTO THE 70S SATURDAY FOR MUCH OF THE SANDHILLS REGION AND POINTS
SOUTH WITH UPPER 60S ELSEWHERE. DEW POINT FORECAST IS PROBLEMATIC
AT THIS POINT...MODEL GUIDANCE HAS STRUGGLE WITH RECENT SIMILAR
EVENTS DISPLAYING A MOIST BIAS OF 20 DEGREES OR MORE AT TIMES
ACROSS THE CENTRAL SANDHILLS AND SOUTHWEST NEBRASKA. ECM DATA AND
THE WRF-ARW SEEM TO HAVE HANDLE THOSE CASES BETTER...KEYING IN ON
THE ADVECTION/MIXING OF ABNORMALLY DRY AIR FROM OUR SOUTHWEST.
THOSE MODELS WERE USED AS A STARTING POINT...AND THEN ADJUSTED
MANUALLY TO ACCOUNT FOR THE INCREASED MIXING/DRYING. IN
ADDITION...THE SHARPENING PRESSURE GRADIENT ELUDED TO ABOVE WILL
WORK IN CONJUNCTION WITH DEEP MIXING GENERATED FROM STEEP LOW
LEVEL LAPSE RATES TO ALLOW FOR GUSTS IN EXCESS OF 25...POSSIBLY 35
MPH...RANGE LATE MORNING THROUGH MUCH OF THE AFTERNOON. GIVEN THE
LARGE TD AND DRY BULB SPREAD...MINIMUM RH OF 15 PERCENT OR LESS IS
LIKELY FOR MUCH OF THE SANDHILLS FIRE ZONES. WILL ISSUE A FIRE
WEATHER WATCH FOR ZONES 204...206...209...210 & 219 WITH THIS
FORECAST PACKAGE WITH THE ANTICIPATION THAT A RFW WILL BE
REQUIRED. SUNDAY IS A BIT LESS APPARENT...INCREASING HIGH LEVEL
CLOUDS WILL SHADE OUR CURED 1HR FUELS AND WINDS ARE FAR LESS
CERTAIN. DESPITE A SIMILAR TD/T SETUP AND FAVORABLE UPPER LEVEL
RIDGE BREAKDOWN PATTERN...WILL HOLD OFF FOR ANOTHER MODEL SUITE
UNTIL ISSUING ANY FIRE HEADLINES FOR SUNDAY. GUIDANCE DISAGREES ON
THE LOCATION OF A SFC TROUGH/WARM FRONT...WITH THE ECM AND GFS OFF
BY GREATER THAN 100 MILES...THERE/S BUST POTENTIAL CONCERNING
MAXIMUM TEMPERATURES ACROSS OUR NORTHERN ZONES ON SUNDAY. AS OF
NOW...GENERALLY SIDED WITH THE ECM CAMP WHICH IS THE WARMER AND
DRIER SOLUTION FOR MUCH OF THE CWA. HIGHS MAY APPROACH 80F SOUTH
OF I80 SUNDAY AFTERNOON...WHERE ALONG THE SOUTH DAKOTA
BORDER...MID 60S IS FORECAST. SOME CONVECTION IS POSSIBLE LATE
SUNDAY AFTERNOON AND EVENING AS THE WAVE TRANSLATES EAST ONTO THE
PLAINS...STEEP LAPSE RATES WILL RESULT IN AT LEAST WEAK ELEVATED
INSTABILITY ACROSS THE ENTIRE CWA...HOWEVER LOWER TROPOSPHERIC
MOISTURE WILL BE LACKING. SFC TD/T SPREADS OF UP TO 40-50F WILL
YIELD HIGH BASED STORMS CAPABLE OF GUSTY OUTFLOW WIND AND POSSIBLY
A FEW CG STRIKES. MODIFIED ARCTIC AIR WILL BE PULLED SOUTH BEHIND
THE WAVE ON MONDAY...WHICH MAY PROVIDE FOR SOME SNOW ACROSS OUR
NORTHERN ZONES...BUT ATTM THE MODELS SEEM TO BE TARGETING THE
NORTHERN PLAINS WITH THE BEST FORCING/HEAVIEST QPF/ACCUMULATIONS.
BEYOND MONDAY...QUASI-ZONAL TO AT TIMES SOUTHWEST FLOW ALOFT WILL
TARGET THE CENTRAL PLAINS THROUGH LATE WEEK. THE MODELS ARE
TRENDING TO ANOTHER TROUGH ENCOMPASSING MUCH OF THE WEST COAST BYE
LATE WEEK. UNSETTLED WEATHER IS PROBABLE IN THIS PATTERN WITH
SEASONAL TO SLIGHTLY BELOW AVERAGE TEMPERATURES LIKELY FOR THE
REGION.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 633 AM CDT FRI MAR 28 2014
AREAS OF MVFR CIGS IN ISOLATED TO SCATTERED SNOW SHOWERS IMPROVE
TO MOSTLY VFR FROM 18Z ONWARD.
ONE AREA OF CONCERN IS ALONG U.S.HIGHWAY 20 WHERE AN ARCTIC FRONT
WILL LIKELY STALL. THE RAP MODEL SUGGESTED MVFR/IFR CIGS NEAR KVTN
THROUGH 02Z THIS EVENING. THE NAM AND GFS INDICATE MVFR IMPROVING
TO VFR AND THIS IS WHAT THE FORECAST USES FOR KVTN.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM SATURDAY AFTERNOON THROUGH SATURDAY
EVENING FOR NEZ204-206-209-210-219.
&&
$$
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS ELKO NV
734 PM PDT SAT MAR 29 2014
.SYNOPSIS...A RAPIDLY DEVELOPING AREA OF LOW PRESSURE AND
ASSOCIATED COLD FRONT WILL BRING VALLEY RAIN AND SNOW TO THE
REGION TONIGHT THROUGH SUNDAY. A SMALL BREAK BETWEEN SYSTEMS
SUNDAY NIGHT BEFORE ANOTHER PACIFIC STORM SYSTEM IMPACTS THE
REGION MONDAY AFTERNOON THROUGH TUESDAY...BRINGING ANOTHER ROUND
OF VALLEY RAIN AND SNOW.
&&
.UPDATE...GUSTY WINDS HAVE NOT DEVELOPED OVER WHITE PINE AND
NORTHEASTERN NYE COUNTIES...AND THE WIND ADVISORY HAS BEEN ALLOWED
TO EXPIRE AT 8 PM. NO OTHER CHANGES AT THIS TIME. RCM
&&
.PREV DISCUSSION... /ISSUED AT 343 PM /
SYNOPSIS...A RAPIDLY DEVELOPING AREA OF LOW PRESSURE AND
ASSOCIATED COLD FRONT WILL BRING VALLEY RAIN AND SNOW TO THE
REGION TONIGHT THROUGH SUNDAY. A SMALL BREAK BETWEEN SYSTEMS
SUNDAY NIGHT BEFORE ANOTHER PACIFIC STORM SYSTEM IMPACTS THE
REGION MONDAY AFTERNOON THROUGH TUESDAY...BRINGING ANOTHER ROUND
OF VALLEY RAIN AND SNOW.
SHORT TERM...SATURDAY NIGHT THROUGH TUESDAY. CURRENT RUC ANALYSIS
INDICATES A RAPIDLY DEEPENING AREA OF LOW PRESSURE FROM EUREKA TO
ELY. THIS LOW PRESSURE IS PROGGED TO MOSTLY STAY STATIONARY AND
DEEPEN THROUGH THE NIGHT AS THE TEMPERATURE GRADIENT TIGHTENS. IN
ADDITION A DEEP PLUME OF PACIFIC MOISTURE IS STREAMING ACROSS
NORTHERN NEVADA...WITH RAIN ALREADY BREAKING OUT ACROSS HUMBOLDT
COUNTY. MODELS ARE ALL IN GOOD AGREEMENT BRINGING A WIDESPREAD
AREA OF .25 TO .50" OF PRECIPITATION OVER THE REGION OVER THE NEXT
24 HOURS...WITH HIGHER AMOUNTS ACROSS THE MOUNTAINS. THE FORECAST
CHALLENGE REMAINS WHEN WILL RAIN CHANGEOVER TO SNOW TONIGHT AND AT
WHAT ELEVATION WILL THE SNOW ACCUMULATE AT. IT LOOKS LIKE THE
VALLEYS OF HUMBOLDT COUNTY WILL REMAIN MOSTLY RAIN...WITH A MIX OF
RAIN AND SNOW TOWARDS THE END OF THE EVENT...BUT NO
ACCUMULATIONS. ACROSS ELKO COUNTY AND CENTRAL NEVADA THE CHANCE
FOR ACCUMULATING SNOW IS MUCH HIGHER...DUE TO HIGHER ELEVATIONS
AND THE BULK OF THE PRECIPITATION FALLING AFTER MIDNIGHT. LOOKS
LIKE RAIN WILL CHANGE OVER TO SNOW THIS EVENING ABOVE 5500FT
ACROSS NORTHERN ELKO COUNTY...WITH RAIN CHANGING OVER TO SNOW FROM
AUSTIN TO SPRING CREEK SOMETIME AFTER MIDNIGHT AS 1000-500MB
THICKNESS VALUES FALL BELOW 549DAM. 700MB FGEN FORCING PEAKS FROM
AUSTIN TO ELKO AROUND 9Z...BEFORE SLIDING INTO EASTERN ELKO AND
WHITE PINE COUNTIES BY SUNDAY MORNING. EXPECTING A MODERATE SNOW-
BAND TO DEVELOP ALONG THIS FGEN FORCING AS IT IS VERTICALLY
STACKED WITH A BROAD AREA OF 500-300MB UPPER LEVEL LIFT DUE TO A
DUAL-CORE JET STREAK CIRCULATION. THIS WILL LEAD TO VERY DEEP LIFT
AND A VERY FAVORABLE DENTRITIC GROWTH REGION...THUS EXPECTING HIGH
END ADVISORY SNOWFALL AMOUNTS ABOVE 6K WHERE IT WILL BE COLD
ENOUGH FOR 12 TO 1 SNOW RATIOS. BELOW 5500 FEET SURFACE TEMPS WILL
LEAD TO LOW RATIOS...THUS LOWER SNOWFALL AMOUNTS...BUT A SLUSHY
INCH COULD EVEN FALL IN ELKO. THE HIGHEST AMOUNTS OF SNOW IN
POPULATED AREAS ARE EXPECTED AT AUSTIN...EUREKA...SPRING
CREEK...AND ELY.
SUNDAY NIGHT THROUGH TUESDAY. SNOW TAPERS OFF DURING THE DAY ON
SUNDAY...BEFORE THE NEXT PACIFIC STORM REACHES THE AREA BY MONDAY
AFTERNOON. MODELS HAVE BEEN STRUGGLING WITH THIS SYSTEM...DUE TO
THE EVOLUTION OF TWO SEPARATE 500MB CIRCULATIONS. CONFIDENCE IS
STILL LOW IN HOW THIS SYSTEM WILL MATERIALIZE OVER THE REGION...BUT
WET SNOW IS PROBABLE MONDAY NIGHT INTO TUESDAY MORNING AS A
SURFACE LOW DEVELOPS OVER NORTHERN NEVADA AND 500MB HEIGHTS DROP
TO 546 DAM. THE BEST CHANCE FOR HEADLINE LEVEL SNOWFALL LOOKS TO
BE ACROSS NORTHERN NEVADA AT THIS TIME.
LONG TERM...TUESDAY NIGHT THROUGH NEXT SATURDAY.
EMPHASIS ON SHORT TERM AND IMPACTS TO AVIATION, SO FEW CHANGES WERE
MADE TO THE LONG TERM GRIDS. LARGE COLD TROUGH LINGERS OVER THE
GREAT BASIN TUESDAY NIGHT AND WEDNESDAY, FOR UNSEASONABLY COLD
WEATHER FOR EARLY APRIL AND SCATTERED SNOW SHOWERS. ADDITIONAL SNOW
AMOUNTS DURING THIS TIME FRAME WILL BE LIGHT, WITH THE LARGEST
IMPACT BEING THE COLD. WITH 700 MB TEMPS NEAR -10C, AFTERNOON
TEMPERATURES WILL STRUGGLE INTO THE 40S WEDNESDAY, AND NW WINDS WILL
MAKE IT FEEL EVEN COLDER.
TEMPERATURES WILL MODERATE THURSDAY UNDER WEAK RIDGING, AHEAD OF THE
NEXT PACIFIC TROUGH. 12Z ECMWF BRINGS THIS PACIFIC TROUGH INLAND
INTO NEVADA IN A WEAKENED STATE ON FRIDAY, WITH SOME RAIN AND SNOW
SHOWERS. 12Z GFS MUCH FASTER AND MUCH WEAKER WITH THIS WAVE, IN FACT
MEDIUM RANGE SOLUTIONS OF GFS/ECMWF/GEM ARE IN MUCH DISAGREEMENT
STARTING ABOUT THURSDAY. SHOWED A GRADUAL WARMING TREND IN THE MAX
TEMP GRIDS FRIDAY AND SATURDAY, BUT CONFIDENCE IS LOW. BT
AVIATION...FOR THE 00Z TAFS...COMPLICATED TAF PACKAGE, WITH SNOW
AND WIND IMPACTING AVIATION OPERATIONS THROUGH THE NEXT 24 HOURS.
MODEL GUIDANCE AGREES THAT INCLEMENT WEATHER WILL OCCUR AT THE TAF
SITES, BUT DIFFER A BIT ON TIMING /WITH THE 12Z GFS A BIT SLOWER/ SO
WILL HOLD OFF ON TEMPO GROUPS UNTIL THE EVENT STARTS TO UNFOLD THIS
AFTERNOON/EVENING.
EXPECT DEGRADED CONDITIONS IN -RA TO BEGIN AT KWMC AROUND 00Z, AND
AT KEKO AROUND 03Z. EXPECTING -RA TO CHANGE TO -SN AT BOTH KWMC/KEKO
APPROXIMATELY 06Z TONIGHT, WITH VIS/CIG MOST LIKELY FALLING TO
IFR/CAT A LANDING MINIMUMS AT KEKO 06-15Z SUN. STRONG COLD FRONT WILL
REACH KWMC BY 09Z, AND KEKO BY 12Z, WITH STRONG NW WINDS GUSTING
30-35 KTS AND LIMITED VIS IN -SHSN. SINCE MOST OF THE SNOW IS
FALLING AT NIGHT AT KEKO, SOME ACCUMULATIONS ON KEKO RUNWAYS ARE
POSSIBLE 06-15Z SUN.
FURTHER SOUTH...CYCLOGENESIS EXPECTED NEAR KELY AFTER 00Z, WITH
STRONG SW/S WINDS GUSTING 30-40 KTS AT TIMES, AT LEAST THROUGH 06Z.
INCLUDED VCTS AT KELY THIS EVENING WITH INSTABILITY PRESENT. STRONG
COLD FRONT PASSAGE APPROXIMATELY 12-15Z SUN, WITH AGAIN STRONG NW
WINDS OF 20-35 KTS. ACCUMULATING SNOW MOST LIKELY AT KELY 12-18Z
SUN, WITH IMPACTS POSSIBLE ON KELY RUNWAYS.
AT KTPH...STRONG SW WINDS THIS AFTERNOON AT 20-30 KTS. COLD FRONT
ARRIVES AT KTPH AROUND 12Z SUN, WITH VERY STRONG NW WINDS FOLLOWING
ITS PASSAGE AT THE KTPH TERMINAL, GUSTING TO 40-45 KTS. LIMITED VIS
IN BRIEF -RASN MOST LIKELY AT KTPH 12-18Z SUN, BUT IMPACTS WILL BE
MUCH LESS HERE COMPARED TO THE OTHER TERMINALS. BT
&&
.LKN WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 5 PM PDT SUNDAY ABOVE 5500 FEET
FOR NORTHERN ELKO COUNTY...NORTHERN LANDER COUNTY AND NORTHERN
EUREKA COUNTY...SOUTHWESTERN ELKO COUNTY.
WINTER WEATHER ADVISORY UNTIL 5 PM PDT SUNDAY ABOVE 6000 FEET
FOR SOUTH CENTRAL ELKO COUNTY...SOUTHERN LANDER COUNTY AND
SOUTHERN EUREKA COUNTY...WHITE PINE COUNTY.
WINTER STORM WARNING UNTIL 5 PM PDT SUNDAY FOR RUBY
MOUNTAINS/EAST HUMBOLDT RANGE.
WIND ADVISORY FROM 5 AM TO 5 PM PDT SUNDAY FOR NORTHWESTERN NYE
COUNTY.
&&
$$
93
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
854 PM EDT SAT MAR 29 2014
.SYNOPSIS...
A MOISTURE LADEN STORM SYSTEM WILL IMPACT OUR REGION TONIGHT INTO
SUNDAY. THIS SYSTEM WILL PRODUCE A MIXTURE OF RAIN...SLEET AND
SNOW...WITH SOME ICE ACCUMULATION ACROSS PORTIONS OF EASTERN
VERMONT. HEAVY RAINFALL ACROSS SOUTHERN VERMONT...COMBINED WITH
MELTING SNOW WILL PRODUCE INCREASED HYDRO CONCERNS OVER THE
WEEKEND.
&&
.NEAR TERM /THROUGH SUNDAY/...
AS OF 840 PM EDT SATURDAY...UPDATED TO UPGRADE PARTS OF THE
NORTHERN ADIRONDACK MOUNTAINS TO WINTER STORM WARNINGS.
PRECIPITATION HAS NOW MADE IT INTO PORTIONS OF SOUTHERN
VERMONT...ADIRONDACKS...AND INTO WATERTOWN NEW YORK. SHOULD
CONTINUE TO SEE IT MOVE NORTHWARD INTO CENTRAL VERMONT BETWEEN
9-10 PM...THE BURLINGTON AREA 10-11 PM..AND ACROSS THE ENTIRE NORTH
COUNTRY BY MIDNIGHT. HEAVIEST PRECIP STILL APPEARS IT WILL FALL BETWEEN
06Z AND 12Z. VERTICAL TEMPERATURE PROFILES REMAIN VERY TRICKY WITH
NEARLY ISOTHERMAL PROFILE FROM THE SURFACE TO 825-MB CENTERED
AROUND 0C. DYNAMIC/EVAPORATIONAL COOLING SHOULD HELP TO COOL THE
COLUMN AT LEAST IN HEAVIER PRECIPITATION IN THE ADVISORY AND
WARNING AREA...ESPECIALLY NORTHERN NEW YORK. ONE CAVEAT TO
NOTE...LATEST RAP SOLUTIONS ARE CONSIDERABLY WARMER AND WOULD
FAVOR MORE RAIN OVER SNOW/SLEET FOR MUCH OF VERMONT. STILL THINK
THAT ENOUGH COOLING TO TAKE PLACE FOR A GENERAL 2-5" OF SNOW FOR
THE NORTHERN HALF OF VERMONT. IN THE ADIRONDACKS...TEMPERATURES
HAVE ALREADY FALLEN TO 32 DEGREES OR LOWER...WITH LOW LEVEL COLD
NORTHEAST FLOW LOCKED IN. WITH AT LEAST 0.75" OF LIQUID
EQUIVALENT PRECIPITATION HEADED INTO SUB-FREEZING AIR...FELT IT
WAS NECESSARY TO UPGRADE TO WARNINGS THERE. EVEN THE WARMER RAP
SOLUTIONS ARE COLD ENOUGH FOR ALL FROZEN PRECIPITATION OVER THE
ADIRONDACKS. EXPECTING PRIMARILY SNOW...ALTHOUGH THE TEMPERATURE
PROFILE IS STILL QUITE MARGINAL SO SOME SLEET/RAIN/FREEZING RAIN
MIX STILL LIKELY AT TIMES. LOOKING AT 4-8" THERE WITH THE
POSSIBILITY OF SOME LOCALLY HIGHER AMOUNTS.
COLD NORTHEAST WINDS ALSO LOCKED INTO THE SAINT LAWRENCE
VALLEY...BUT BOUNDARY LAYER WILL BE MORE MARGINAL AS ITS A DEEPER
VALLEY...AND PRECIP AMOUNTS LIGHTER...SO ADVISORY LEVEL SNOWS OF
3-5" STILL LOOK GOOD.
ELSEWHERE ACROSS SOUTHERN VERMONT...PRECIPITATION WILL FALL AS
MAINLY RAIN...WITH SOME MIXED SNOW/SLEET/FREEZING RAIN. SNOW
ACCUMULATIONS WILL GENERALLY BE LESS THAN ONE INCH...WITH SOME ICE
ACCRUAL OF UP TO A TENTH OF AN INCH IN ISOLATED LOCATIONS. BIGGEST
CONCERN THERE WILL BE 1-1.5" OF RAIN WHICH MAY LEAD TO ICE JAM
FLOODING.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
AS OF 402 PM EDT SATURDAY...FOR SUNDAY NIGHT INTO MONDAY...WE WILL
HAVE TO WATCH FOR THE POSSIBILITY OF ANOTHER ROUND OF MIXED
PRECIPITATION. THIS DUE TO SHORTWAVE ROTATING AROUND THE SLOWLY
DEPARTING UPPER LOW. MODELS HAVE TRENDED FURTHER WEST WITH THE
UPPER LOW AND SHORTWAVE...SO CONFIDENCE INCREASING THAT WE WILL AT
LEAST SEE SOME LIGHT SLEET AND OR RAIN/FREEZING RAIN/DRIZZLE
SUNDAY NIGHT INTO MONDAY. GREATEST CHANCES WILL BE OVER EASTERN
ZONES DUE PROXIMITY WITH UPPER LOW. TEMPS MARGINAL FOR SNOW/RAIN
OR MIXED PRECIPITATION ONCE AGAIN. LOOK FOR LOWS SUNDAY NIGHT IN
THE MID 20S TO LOWER 30S AND HIGHS MONDAY NEAR 40. SLOW
IMPROVEMENT MONDAY NIGHT AS THE UPPER LOW EXITS TO THE EAST.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 325 PM EDT SATURDAY...DRY START TO THE PERIOD TUESDAY
BEFORE UPPER LVL TROUGH...ASSOCIATED WITH CLOSED SFC
LOW...TRAVELS FROM THE NRN GREAT LAKES NEWD NEAR JAMES BAY BY MID
WEDNESDAY. THIS LOW WILL HAVE A WEAK FRONTAL BOUNDARY DRAPED
SOUTH...WHICH WILL BRING LOW CHC OF SHOWERS TO THE NORTH COUNTRY
TUESDAY NGT INTO WEDNESDAY...AS THIS BOUNDARY WILL HAVE LIMITED
MOISTURE AND MAIN UPPER LVL ENERGY WILL BE FAR NORTH OF THE FA.
FOR ANY PRECIP THAT DOES OCCUR...TUESDAY NGT WILL SEE SOME
SNOW...BUT WARMING TEMPS ON WEDNESDAY WILL TRANSITION SN INTO RA
BEFORE TAPERING OFF.
ANOTHER SYSTEM APPROACHING FROM CENTRAL USA WILL BRING WARM FRONT
TO THE NE LATE THURSDAY INTO FRIDAY. GFS AND ECMWF DIFFER WITH
ECMWF PERSISTING WITH RIDGE. THIS WOULD KEEP THREAT OF PRECIP TO
OUR SOUTH THRU LATE FRIDAY. MUCH UNCERTAINTY FOR THE LATTER HALF
OF THE WEEK GOING INTO THE WKND.
TEMPS THROUGHOUT THE PERIOD WILL BE NEAR NORMAL WITH MAX TEMPS IN
THE 40S IN THE VALLEYS AND 30S IN THE MTNS. MIN TEMPS WILL BE IN
THE U20S-L30S IN THE VALLEYS AND UPPER TEENS TO L20S IN THE MTNS.
&&
.AVIATION /01Z SUNDAY THROUGH THURSDAY/...
THROUGH 00Z MONDAY...VERY ACTIVE PERIOD WITH AVIATION WX
CONDITIONS DETERIORATING RAPIDLY THIS EVENING AND OVERNIGHT. IFR
CONDITIONS DEVELOP AREAWIDE BETWEEN 02-05Z IN ASSOCIATION WITH
MODERATE TO HEAVY MIXED WINTRY PCPN MOVING IN FROM THE SOUTH. NY
TERMINALS ARE IN COLDER AIR MASS...AND WILL SEE MORE SNOW/SLEET.
IN VT...MIX OF HEAVY WET SNOW/SLEET/RAIN IS EXPECTED THRU MID-MORNING
SUNDAY WITH TEMPS IN THE LOW-MID 30S. SFC WINDS WILL BE N-NE AT
10-15KTS...EXCEPT LOCALLY 15-20KTS WITH VALLEY CHANNELING EFFECTS
AT MSS. SLUSHY SNOW/SLEET ACCUMULATION WILL CAUSE IMPACT TO
AIRPORT GROUND OPS ALL SITES 02-15Z SUNDAY. PRECIPITATION WINDS
DOWN W-E SUNDAY AFTN WITH IMPROVEMENT TO MVFR CIGS.
OUTLOOK 00Z MONDAY THROUGH THURSDAY...
00Z MONDAY TO 18Z MONDAY...TRENDING SLOWLY TO VFR FROM WEST TO
EAST AS LIGHT RAIN/SNOW TAPERS OFF. BEST SHOT AT CONTINUED LIGHT
PCPN AND MVFR/IFR AT ERN TERMINALS OF KMPV/KRUT. AGAIN...HIGHEST
CONFIDENCE OF BETTER FLIGHT CONDS AT NRN NY TERMINALS WITH
CONTINUED UNCERTAINTY FURTHER EAST.
18Z MONDAY THROUGH 00Z WEDNESDAY...VFR WITH HIGH PRESSURE.
00Z WEDNESDAY THROUGH 00Z THURSDAY...VFR ALTHOUGH SOME BRIEF
PERIODS OF MVFR POSSIBLE IN SCATTERED RAIN/SNOW SHOWERS AS COLD
FRONT CROSSES REGION.
00Z THURSDAY ONWARD...VFR W/MVFR PSBL LATE THURSDAY AS WARM FRONT
APPROACHES FROM SW...BRINGING PRECIP SOUTH TO NORTH.
&&
.HYDROLOGY...
AS OF 325 PM EDT SATURDAY...PRECIPITATION WILL BEGIN TO EDGE INTO
SOUTHERN VERMONT LATE THIS AFTN...PROGRESSING NORTHWARD
THROUGHOUT THE EVENING. THIS PRECIPITATION IS EXPECTED TO
CONTINUE THROUGH SUNDAY NIGHT...RESULTING IN OUR SOUTHERN
WATERSHEDS RECEIVING THE MOST RAINFALL ON THE ORDER OF 1-2
INCHES. AREAS FURTHER NORTH AND WEST WILL SEE MORE OF A MIXED
PRECIPITATION EVENT...WITH LESSER RAINFALL AMOUNTS.
WITH SOUTHERN WATERSHEDS RECEIVING MOSTLY RAIN...EXPECT SNOWPACK
TO ABSORB SOME OF THIS RAINFALL AS TEMPERATURES WILL GENERALLY BE
IN THE MID TO UPPER 30S THROUGHOUT THE EVENT...LEADING TO LIMITED
MELTING OF SNOWPACK. ONLY A FEW HUNDREDTHS OF AN INCH OF SNOW
WATER MELT PER HOUR EXPECTED ON TOP OF RAINFALL WILL RESULT IN
MODEST TO LOCALLY SHARP RISES IN EXCESS OF 4-5 FEET SUNDAY
MORNING/AFTERNOON. ENSEMBLE FORECASTS INDICATE NO RIVER FLOODING
EXPECTED....BUT WATER LEVEL RISES MAY BE MORE THAN SUFFICIENT TO
PRODUCE ICE MOVEMENT AND/OR BREAKUP ACROSS SCATTERED WATERSHEDS.
WILL KEEP FLOOD WATCH IN EFFECT FOR CENTRAL AND SOUTHERN VERMONT.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...WINTER WEATHER ADVISORY UNTIL 2 PM EDT SUNDAY FOR VTZ001>010-
012-016>019.
FLOOD WATCH THROUGH MONDAY MORNING FOR VTZ009>012-019.
NY...WINTER STORM WARNING UNTIL 2 PM EDT SUNDAY FOR NYZ030-031-034.
WINTER WEATHER ADVISORY UNTIL 2 PM EDT SUNDAY FOR NYZ026>029-
035-087.
&&
$$
SYNOPSIS...RJS
NEAR TERM...MUCCILLI
SHORT TERM...RJS
LONG TERM...KGM
AVIATION...BANACOS/KGM
HYDROLOGY...KGM
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
921 PM EDT SAT MAR 29 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE OFFSHORE LATE TONIGHT. A SURFACE TROUGH WILL LINGER
JUST WEST OF THE AREA INTO MONDAY. WEAK HIGH PRESSURE BUILDS OVER THE
REGION MONDAY NIGHT AND TUESDAY. THE HIGH WILL MOVE SOUTH OF THE AREA
TUESDAY NIGHT AND WEDNESDAY. ANOTHER COLD WILL APPROACH THE AREA BY LATE
WEEK.
&&
.NEAR TERM /THROUGH SUNDAY/...
AS OF 920 PM SATURDAY...A TORNADO WATCH REMAINS IN EFFECT FOR THE
WESTERN PORTIONS OF EASTERN NC (MAINLY WEST OF HIGHWAY 17) UNTIL
1 AM. HAVE BEEN WATCHING A PERSISTENT SUPERCELL THUNDERSTORM WITH
A DEEP AND PERSISTENT MESCALINE MOVING THROUGH CENTRAL NC SINCE
730 PM. THIS STORM WILL REMAIN NW OF OUR AREA. TO THE SOUTH OF
THIS SYSTEM ADDITIONAL SHOWERS AND POSSIBLE THUNDERSTORMS WERE
DEVELOPING. THE HRRR MODEL BRINGS THIS CONVECTION INTO OUR PORTION
OF THE COASTAL PLAIN AROUND 11 PM SO WILL CONTINUE TO MONITOR. SO
FAR STORMS HAVE NOT WEAKENED WITH LOSS OF HEATING A SIGNAL THAT
THEY ARE BEING DYNAMICALLY FORCED. WILL CONTINUE TO KEEP POPS IN
THE CHANCE RANGE AS THE COVERAGE IN THE HIGH RESOLUTION MODELS
REMAINS SCATTERED. LATE TONIGHT DRY SLOTTING SHOULD END ANY
CHANCE OF PRECIPITATION UNTIL LATER SUNDAY WHEN THE UPPER LEVEL
LOW MOVES THROUGH. USED A BLEND OF THE ECMWF/MET MOS FOR LOWS WITH
READINGS IN THE UPPER 40S/LOWER 50S EXPECTED.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH 6 PM SUNDAY/...
AS OF 315 PM SATURDAY...WILL HAVE A BIT OF A LULL IN PRECIPITATION
DURING THE MORNING HOURS ON SUNDAY...BUT AS UPPER LOW CROSSES TO
OUR NORTH NEAR THE NORTH CAROLINA/VIRGINIA BORDER...THE STEEP
LAPSE RATES AND MODEST MOISTURE WILL LEAD TO A HIGH CHANCE OF
SHOWERS SUNDAY AFTERNOON. WITH GOOD COLD AIR ADVECTION...TEMPERATURES
WILL ONLY RECOVER ABOUT 5 TO 7 DEGREES AND WILL FOLLOW THE COOLER
NAM MOS GUIDANCE SUNDAY SHOWING HIGH TEMPERATURES IN THE LOW/MID
50S WITH GUSTY W/WNW WINDS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
AS OF 3 PM SAT...THE LONG TERM PORTION OF THE FORECAST CAN BE
SUMMARIZED AS DRYING OUT AND WARMING UP. MADE ONLY MINOR TWEAKS
TO THE POPS ENDING THE RAIN SUNDAY NIGHT. SURFACE/UPPER LOW AND
ASSOCIATED MOISTURE MOVE OFF TO THE NORTHEAST WITH RIDGING SURFACE
AND ALOFT BUILDING IN FROM THE WEST. RIDGING BEGINS TO BREAK DOWN
LATE IN THE WEEK AS AN UPPER LOW AND SURFACE COLD FRONT APPROACH
FROM THE WEST. THE COLD FRONT WILL MOVE THROUGH FRIDAY NIGHT AND
CARRIED A LOW CHANCE POP FOR SHOWERS AND STORMS. DRYING OUT
SATURDAY WITH THE FRONT OFF THE COAST AND A SURFACE HIGH BUILDING
TO THE NORTHWEST. NORTHWEST FLOW ON MONDAY WILL DIMINISH AND
SLOWLY TRANSITION TO A WEST TO SOUTHWEST FLOW BY TUESDAY NIGHT AND
CONTINUE INTO FRIDAY. HIGHS THIS WEEK WILL CLIMB WELL INTO THE
70S ACROSS MOST INLAND AREAS BEGINNING TUESDAY AS WINDS BECOME
SOUTHERLY.
&&
.AVIATION /01Z SUNDAY THROUGH THURSDAY/...
SHORT TERM /TONIGHT AND SUNDAY/...
AS OF 640 PM SATURDAY...SOME IFR CEILINGS ARE STILL BEING
REPORTED AT THE TAF SITES BUT THINK THE TREND IS FOR IMPROVEMENT
AS THE THREAT FOR WIDESPREAD PRECIPITATION IS OVER AND SOME DRYING
IS EXPECTED TO MOVE INTO THE AREA LATER THIS EVENING. BASED ON
UPSTREAM OBSERVATIONS AND TRENDS IN THE 12Z/18Z NAM FORECAST
SOUNDINGS WILL FORECAST CONDITIONS IMPROVING TO MVFR AND
CONTINUING FOR MUCH OF TONIGHT THEN A BRIEF PERIOD OF VFR
CONDITIONS AROUND 09Z DURING THE PEAK OF DRYING. AN UPPER LOW IS
FORECAST TO MOVE ACROSS NC SUNDAY. ASSOCIATED MOISTURE WILL LEAD
TO A RETURN TO MVFR CEILINGS 12-14Z WHICH WILL THEN PERSIST FOR
MUCH OF THE DAY. THERE COULD ALSO INTERMITTENT LIGHT RAIN OR
DRIZZLE AT TIMES. GUSTY SOUTHERLY WINDS TONIGHT WILL BECOME
WESTERLY ON SUNDAY.
LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 3 PM SAT...IFR/MVFR CONDITIONS SUNDAY NIGHT WILL BECOME VFR
ON MONDAY AS MOISTURE EXITS TO THE NORTHEAST AND A SURFACE/UPPER
RIDGE BUILDS IN FROM THE WEST. NORTHWEST WINDS SUNDAY NIGHT AND
MONDAY WILL BECOME WEST TO SOUTHWEST TUESDAY NIGHT AND CONTINUE
THROUGH THURSDAY. MODEL SOUNDINGS INDICATE LATE NIGHT/EARLY
MORNING STRATUS/FOG POSSIBLE EACH MORNING WITH VERY LIGHT WINDS
AND BOUNDARY LAYER MOISTURE.
&&
.MARINE...
SHORT TERM /TONIGHT AND SUNDAY/...
AS OF 920 PM SATURDAY...NO CHANGES TO PREVIOUS FORECAST THINKING
OTHER THAN TO EXTEND THE ADVISORIES FOR THE SOUNDS THROUGH EARLY
MONDAY. GUSTY SE/S WINDS WILL CONTINUE TONIGHT AND HAVE ADDED THE
ALBEMARLE SOUND TO THE SMALL CRAFT ADVISORY THAT WILL REMAIN IN
EFFECT UNTIL 5 AM SUNDAY. WILL INITIALIZE WINDS AT 20 TO 25 KNOTS
FOR ALL WATERS...EXCEPT 25 TO 30 KNOTS OVER THE OREGON INLET TO
OCRACOKE LEG WHERE WINDS CONTINUE TO BE STRONGEST. THESE WINDS
SHOULD SETTLE DOWN AFTER MIDNIGHT AS WINDS VEER TO MORE SW LATE.
PER LATEST NWPS WAVE MODEL...SEAS OF 9 TO 13 FEET WILL PREVAIL
OVER THE NORTHERN AND CENTRAL WATERS WITH GENERALLY 7 TO 10 FEET
OVER SOUTHERN PORTIONS...WITH A SLIGHT DROP IN THE MORE WESTERLY
FLOW EXPECTED DURING THE DAY ON SUNDAY.
LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 3 PM SAT...AN OVERALL IMPROVING TREND SEEN IN MARINE
CONDITIONS THROUGH THE LONG TERM. SURFACE/UPPER LOW WILL MOVE OFF
TO THE NORTHEAST SUNDAY NIGHT WITH SURFACE/UPPER RIDGE QUICKLY
BUILDING IN AND LINGERING FOR MOST OF THE WEEK. SMALL CRAFT
CONDITIONS WILL END FROM SOUTH TO NORTH MONDAY AND MONDAY NIGHT.
NORTHWEST FLOW SUNDAY NIGHT INTO MONDAY WILL BECOME WEST TO
SOUTHWEST TUESDAY NIGHT THROUGH THURSDAY.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT MONDAY FOR AMZ130-135.
SMALL CRAFT ADVISORY UNTIL 2 AM EDT TUESDAY FOR AMZ152-154.
SMALL CRAFT ADVISORY UNTIL 5 PM EDT MONDAY FOR AMZ156-158.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR AMZ150.
&&
$$
SYNOPSIS...CTC
NEAR TERM...CTC/JME
SHORT TERM...CTC
LONG TERM...HSA
AVIATION...JME/HSA/LEP
MARINE...CTC/JME/HSA
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
348 PM EDT FRI MAR 28 2014
.SYNOPSIS...
A SLOW-MOVING COLD FRONT WILL APPROACH FROM THE NORTHWEST TONIGHT.
DEVELOPING LOW PRESSURE MOVING ACROSS TO THE NORTH WILL PULL THE FRONT
THROUGH THE AREA LATE SATURDAY INTO SATURDAY NIGHT. THE LOW WILL
CONTINUE DEEPENING AS IT MOVES TO THE NORTHEAST SUNDAY AND SUNDAY
NIGHT WITH HIGH PRESSURE BUILDING IN FROM THE WEST THROUGH MONDAY.
THE HIGH WILL MOVE SOUTH OF THE AREA TUESDAY. ANOTHER COLD FRONT WILL
APPROACH THE AREA BY FRIDAY OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 345 PM FRIDAY...LOW-LEVEL MOISTURE TRANSPORT AND
PRECIPITABLE WATER VALUES CONTINUE TO CREEP UP ACROSS THE CENTRAL
PART OF THE STATE AHEAD OF SLOW-MOVING COLD FRONT IN THE TENNESSEE
VALLEY. RADAR SHOWING SOME LIGHT SHOWERS GRADUALLY MOVING INTO THE
COASTAL PLAINS...WHICH IS WELL DEPICTED BY THE LATEST 4 KM NSSL
WRF AND RAP MODELS. THE ATMOSPHERE IS STABLE AND DO NOT EXPECT
THUNDER THROUGH MOST OF THE OVERNIGHT HOURS. HAVE TRENDED POPS
INTO THE LIKELY RANGE...MAINLY AFTER MIDNIGHT AS THE PRECIPITATION
INCREASES AND MOVES EAST. WITH THE INCREASED CLOUDS...PRECIP AND
SOUTHERLY WINDS...MINIMUM TEMPERATURES TONIGHT WILL BE VERY
MILD...REMAINING MAINLY IN THE UPPER 50S TO AROUND 60 DEGREES.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
AS OF 345 PM FRIDAY...WIDESPREAD SHOWERS WILL COVER THE CWA ON
SATURDAY AND CONTINUE THE FORECAST OF CATEGORICAL POPS...WITH SOME
EMBEDDED THUNDERSTORMS. SPC CONTINUES TO HAVE OUR CWA IN A SLIGHT
RISK OF SEVERE THUNDERSTORMS FOR SATURDAY. EXPECT MORNING
CLOUDINESS AND SHOWERS TO LIMIT THE INSTABILITY DURING THE FIRST
HALF OF THE DAY...BUT WITH BETTER DIRECTIONAL SHEAR AND LI`S OF -2
TO -4 LATE IN THE DAY...THINK THE POTENTIAL FOR ANY SEVERE WEATHER
WILL BE BETTER...ESPECIALLY IN THE 20Z-02Z TIME FRAME. DAMAGING
WINDS GUSTS WILL BE THE MAIN THREAT AND GIVEN THE BACKED LOW-LEVEL
FLOW...CANNOT RULE OUT A BRIEF TORNADO. TEMPERATURES WILL WARM
INTO THE MID 60S OUTER BANKS TO MID 70S INLAND...DESPITE THE CLOUD
COVER...GIVEN GUSTY SOUTHERLY WINDS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
AS OF 3 PM FRI...GFS/ECMWF IN RATHER GOOD AGREEMENT FOR MOST OF
THE LONG TERM. WIDESPREAD SHOWERS AND STORMS SATURDAY NIGHT WILL
SLOWLY TAPER OFF FROM THE WEST AFTER MIDNIGHT AS THE COLD FRONT
MOVES EAST. NO CHANGES TO POPS. FRONT WILL MOVE OFF THE COAST
SHORTLY AFTER 12Z SUNDAY. PLENTY OF WRAPAROUND MOISTURE ON SUNDAY
SO EXPECT CLOUDS AND SCATTERED SHOWERS TO CONTINUE THROUGH THE DAY
WITH THE BEST CHANCE ACROSS THE NORTHEAST COUNTIES. SHOWERS WILL
FINALLY END SUNDAY EVENING AS THE UPPER LOW AND DEEP MOISTURE MOVE
AWAY. UPPER LEVEL RIDGING WILL BE DOMINANT NEXT WEEK...WHILE AT
THE SURFACE HIGH PRESSURE OVER THE SOUTHEAST MONDAY SHIFTS EAST
AND REMAINS OFF THE COAST THROUGH THE END OF THE WEEK...MAKING FOR
A PERIOD OF DRY AND WARM WEATHER FOR THE AREA. THE NEXT CHANCE OF
RAIN COMES WITH THE NEXT FRONT APPROACHING ON FRIDAY.
&&
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
SHORT TERM /TONIGHT AND SATURDAY/...
AS OF 115 PM FRIDAY...VFR CONDITIONS WILL CONTINUE THROUGH THE
AFTERNOON WITH SUB-VFR FORECASTED THIS EVENING THROUGH TOMORROW. A
POTENT LOW PRESSURE SYSTEM WILL BE APPROACHING THE REGION FROM THE
WEST. THEREFORE...EXPECT CLOUDS TO INCREASE/LOW THROUGH THE LATE
AFTERNOON/EVENING HOURS. GUSTY SOUTHERLY FLOW WILL CONTINUE FOR
THE NEXT COUPLE OF HOURS BUT SUBSIDE AS THE SURFACE HEATING
DIMINISHES. RAIN SHOULD ARRIVE THIS EVENING THROUGH THE OVERNIGHT
HOURS WITH VSBYS LOWERING IN RESPONSE. ANTICIPATE MAINLY MVFR AND
SOME PATCHY IFR CIGS/VSBYS THROUGH THE OVERNIGHT HOURS INTO
SATURDAY MORNING. SSE WINDS AROUND 5-10KTS EXPECTED SATURDAY.
LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 3 PM FRI...GFS/ECMWF IN RATHER GOOD AGREEMENT FOR MOST OF
THE LONG TERM. WIDESPREAD SHOWERS AND STORMS SATURDAY NIGHT WILL
SLOWLY TAPER OFF FROM THE WEST AFTER MIDNIGHT AS THE COLD FRONT
MOVES EAST. NO CHANGES TO POPS. FRONT WILL MOVE OFF THE COAST
SHORTLY AFTER 12Z SUNDAY. PLENTY OF WRAPAROUND MOISTURE ON SUNDAY
SO EXPECT CLOUDS AND SCATTERED SHOWERS TO CONTINUE THROUGH THE DAY
WITH THE BEST CHANCE ACROSS THE NORTHEAST COUNTIES. SHOWERS WILL
FINALLY END SUNDAY EVENING AS THE UPPER LOW AND DEEP MOISTURE MOVE
AWAY. UPPER LEVEL RIDGING WILL BE DOMINANT NEXT WEEK...WHILE AT
THE SURFACE HIGH PRESSURE OVER THE SOUTHEAST MONDAY SHIFTS EAST
AND REMAINS OFF THE COAST THROUGH THE END OF THE WEEK...MAKING FOR
A PERIOD OF DRY AND WARM WEATHER FOR THE AREA. THE NEXT CHANCE OF
RAIN COMES WITH THE NEXT FRONT APPROACHING ON FRIDAY.
&&
.MARINE...
SHORT TERM /TONIGHT AND SATURDAY/...
AS OF 345 PM FRIDAY...HAVE EXTENDED THE SMALL CRAFT ADVISORY SOUTH
OF OREGON INLET UNTIL 12Z ON SATURDAY MORNING. WINDS ARE RAMPING
UP WITH GUSTS TO 20 KNOTS AT DUCK PIER...AND 25 KNOTS AT DIAMOND
BUOY. SEAS CONTINUE TO HOVER AROUND 6 FEET AT DIAMOND SHOALS.
EXPECT GUSTY SOUTHERLY WINDS AT 15 TO 20 KNOTS...EXCEPT UP TO 25
KNOTS AT TIMES OVER THE WATERS SOUTH OF OREGON INLET TONIGHT INTO
SATURDAY. PER LATEST SWAN/NWPS...SEAS AS HIGH AS 6 TO 7 FEET ARE
LIKELY...ESPECIALLY OVER THE CENTRAL WATERS TONIGHT AND EARLY
SATURDAY. THERE WILL BE A LULL IN WINDS/SEAS DURING LATE MORNING
INTO AFTERNOON SATURDAY. AN ADDITIONAL SMALL CRAFT ADVISORY WILL
LIKELY BE REQUIRED LATER TONIGHT FOR ALL WATERS BEHIND THE STRONG
FRONT SATURDAY NIGHT.
LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 3 PM FRI...GFS/ECMWF IN CLOSE AGREEMENT AND USED A BLEND.
VERY POOR BOATING CONDITIONS TO START OUT THE LONG TERM WITH ONLY
SLOW IMPROVEMENT THROUGH THE PERIOD. STRONG SMALL CRAFT WIND/SEA
CONDITIONS TO BEGIN WITH ALONG AND AHEAD OF THE COLD FRONT. THE
FRONT WILL MOVE OFF THE COAST AROUND 12Z SUNDAY. WINDS WILL VEER
FROM SOUTHWEST SATURDAY EVENING TO WEST SUNDAY MORNING THEN TO
NORTHWEST DURING THE DAY SUNDAY. SMALL CRAFT CONDITIONS WILL
GRADUALLY END FROM SOUTH TO NORTH SUNDAY NIGHT INTO MONDAY NIGHT.
HIGH PRESSURE OVER THE AREA MONDAY WILL SHIFT OFF THE SOUTHEAST
COAST TUESDAY AND WEDNESDAY WITH LIGHT WEST TO SOUTHWEST WINDS AND
SEAS AVERAGING 2-4 FEET.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 AM EDT SATURDAY FOR AMZ152-154-
156-158.
&&
$$
SYNOPSIS...CTC
NEAR TERM...CTC
SHORT TERM...CTC
LONG TERM...HSA
AVIATION...HSA/LEP
MARINE...CTC/HSA
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
312 PM EDT FRI MAR 28 2014
.SYNOPSIS...
A COLD FRONT EXTENDING FROM THE GREAT LAKES INTO TEXAS WILL MOVE
INTO CAROLINAS EARLY SUNDAY MORNING. UNTIL THEN...RELATIVELY WARM
AND HUMID AIR WILL STREAM NORTHWARD...ACCOMPANIED BY PERIODS OF
SHOWERS AND THUNDERSTORMS. HIGH PRESSURE WILL FOLLOW THE COLD
FRONT...BRINGING COOLER TEMPERATURES SUNDAY AND MONDAY. THE CENTER
OF THE HIGH WILL MOVE OVERHEAD MONDAY NIGHT INTO TUESDAY.
TEMPERATURES SHOULD CLIMB WELL ABOVE NORMAL LATER NEXT WEEK. A COLD
FRONT MAY REACH THE AREA NEXT FRIDAY...BRINGING A RISK FOR SHOWERS.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 300 PM FRIDAY...A LARGE MCS ALONG THE EASTERN GULF COAST
DOMINATES THE WEATHER PATTERN ACROSS THE SOUTHEASTERN U.S.
THE CONVECTIVE ELEMENTS OF THIS FEATURE ARE LARGELY LIMITED TO
SOUTHERN GEORGIA AND POINTS SOUTH...WITH AN EXPANSIVE BUT
DETERIORATING AREA OF LIGHT RAIN EXTENDING INTO NORTH GEORGIA AND
WESTERN SOUTH CAROLINA. THIS ACTIVITY SHOULD MOVE EASTWARD...
AFFECTING THE SC PEE DEE REGION EARLY THIS EVENING. OTHER GENERALLY
LIGHT SHOWERS DEVELOPING IN A WEAKLY UNSTABLE AIRMASS ACROSS THE
EASTERN CAROLINAS MAY CONTINUE INTO THE EVENING HOURS AS WELL AS
SMALL ELEVATED INSTABILITY IS MAINTAINED BY A SOUTHERLY FLOW ACROSS
THE GULF STREAM OFF THE GEORGIA AND SOUTH CAROLINA COAST.
THE UPPER LEVEL DISTURBANCE THAT HELPED KICK OFF THE GULF COAST MCS
WILL TURN NORTHEASTWARD TONIGHT...APPROACHING THE EASTERN CAROLINAS
LATE. WHILE A RENEWED BLOWUP OF CONVECTION IS NOT ANTICIPATED DUE TO
MEAGER INSTABILITY...A DIFLUENT UPPER LEVEL PATTERN AND AN
INCREASING NEGATIVE TILT TO THE TROUGH SHOULD ENHANCE RAIN/SHOWER
POTENTIAL OVERNIGHT ALL THE WAY DOWN TO THE COAST. WHILE I CAN`T
BRING MYSELF TO PUT 100 POPS IN THE FORECAST...80-90 PERCENT SEEMS
APPROPRIATE. PRECIPITABLE WATER VALUES SHOULD GROW TO 1.5 INCHES
AFTER MIDNIGHT.
IN TERMS OF MODEL SOLUTIONS...IT IS INTERESTING TO SEE HOW THE
MODELS HAVE HANDLED (OR MISHANDLED) TWO ASPECTS OF THE WEATHER
TODAY. ONE IS THE RELATIVELY LIGHT WINDS OVER THE COASTAL WATERS...
PARTICULARLY WHEN CONTRASTED TO THE RATHER BREEZY CONDITIONS
EXPERIENCED INLAND TODAY. MOST SYNOPTIC GUIDANCE (PARTICULARLY THE
GFS) HAS BEEN TOO STRONG WITH MARINE WIND SPEEDS ALL DAY. ALSO OF
NOTE IS THE PERSISTENT AREA OF LIGHT SHOWERS THAT MOVED INTO
GEORGETOWN THIS MORNING AND NOW COVERS BRUNSWICK COUNTY ACROSS
WHITEVILLE INTO LUMBERTON AND ELIZABETHTOWN. THIS ACTIVITY HAS BEEN
WELL-FORECAST BY THE HRRR AND NAM BUT NOT THE GFS. PREFERRED MODELS
TONIGHT INCLUDE THE HRRR IN THE VERY NEAR-TERM...THEN THE 12Z NAM
AND 12Z CANADIAN OVERNIGHT.
WITH SOUTHERLY WINDS AND CLOUDS CONTINUING OVERNIGHT LOWS SHOULD
ONLY FALL TO 59-60 INLAND WITH 57-58 NEAR THE BEACHES DUE TO WINDS
BLOWING IN OFF THE COLDER NEARSHORE WATERS. THE NAM MOS GUIDANCE IS
MUCH CLOSER TO MY IDEAS THAN THE GFS MOS.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
AS OF 300 PM FRIDAY...THE MAIN CHALLENGE CONTINUES TO CENTER AROUND THE
COMPLEX STORM SYSTEM MOVING ACROSS THE SOUTHEAST. TIMING AND
INTENSITY OF RAINFALL AND ASSOCIATED THUNDERSTORMS REMAIN THE MAIN
ISSUES. I HAVE LEANED HEAVILY TOWARD THE GFS FOR THE LATEST UPDATES
TO THE SHORT TERM.
INITIALLY WE COULD HAVE A LARGE SWATH OF RAIN COMING OFF THE
ATLANTIC. AFTER THIS...THERE SHOULD BE A LULL IF YOU WILL WITH SOME
NVA IN THE WAKE OF THIS INITIAL FEATURE. THE MAIN SHORTWAVE FINALLY
GETS ORGANIZED AND MOVES OFF TO THE EAST/NORTHEAST SATURDAY
AFTERNOON WITH YET ANOTHER DEEP MOISTURE FEED FROM THE GULF OF
MEXICO WITH THE ASSOCIATED COLD FRONT. I HAVE INCREASED POPS FOR
LATE AFTERNOON ACROSS WESTERN AREAS AND THE EVENING HOURS FOR
COASTAL SITES. SEVERE PARAMETERS REMAIN MARGINAL AND CONTINUE TO
HINGE ON THE AMOUNT OF INSTABILITY THE IS ABLE TO DEVELOP.
LARGE DIFFERENCES IN TEMPERATURE GUIDANCE WITH THE NAM/MET NUMBERS
QUITE A BIT LOWER FOR DAYTIME HIGHS SATURDAY. I WOULD EXPECT ANY
BREAKS AND THERE SHOULD BE AT LEAST A FEW WILL ALLOW HIGHS TO JUMP
MORE TOWARD THE GFS/MAV NUMBERS. GUIDANCE TRENDS CLOSER SATURDAY
NIGHT AND SUNDAY.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 300 PM FRIDAY...THE LONG TERM APPEARS TO OFFER RAIN-FREE
WEATHER. AS FAR AS TEMPERATURES GO DAYTIME HIGHS WILL AVERAGE
ABOUT A CATEGORY ABOVE CLIMO WHILST NIGHTTIME LOWS SHOULD BE EVEN
MILDER. HIGH PRESSURE SLIDES INTO FLORIDA ON MONDAY KEEPING LOCAL
WINDS RATHER LIGHT. MEANWHILE UPPER RIDGING BUILDS IN FROM THE
WEST. TUESDAY THROUGH WEDNESDAY WILL SHIFT THE HIGH SLIGHTLY
EASTWARD WHILE THE UPPER LEVEL WAVE FLATTENS. END RESULT WILL BE A
SLIGHT BOLSTERING OF THE WARM ADVECTION INTO THE REGION. UPPER
LEVEL AMPLITUDE WILL THEN INCREASE AGAIN THURSDAY INTO FRIDAY AS A
STORM SYSTEM MOVES OUT OF THE ROCKIES AND DEVELOPS INTO THE PLAINS
THURSDAY...MOVING INTO OHIO VALLEY COME FRIDAY.
&&
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
AS OF 18Z...QUITE A BIT OF UNCERTAINTY WITH RESPECT TO THE TIMING OF
THE PRECIP...AS WELL AS CEILINGS OVERNIGHT. SOUTHERLY GRADIENT WILL
CAUSE WINDS TO GUSTS OVER 20 KTS AT TIMES...ESPECIALLY ALONG THE
COAST. SCATTERED SHOWERS WILL GIVE WAY TO MORE WIDESPREAD LIGHT TO
MODERATE RAIN THIS EVENING AS DEEP MOISTURE MOVES INTO THE REGION.
RAIN CHANCES WILL BE HIGHEST INLAND THIS EVENING...SPREADING TO THE
COAST A FEW HOURS LATER. CEILINGS ARE A BIT PROBLEMATIC...BUT WILL
GO FOR MVFR PREDOMINATELY WITH POCKETS OF IFR POSSIBLE. TIME HEIGHT
INDICATES THERE MAY BE A LULL IN THE PRECIP OF ABOUT 6-7 HOURS
THROUGH THE LATE OVERNIGHT HOURS. SATURDAY...MODERATE TO PERHAPS
HEAVY PRECIP SPREADING FROM WEST TO EAST. AN EMBEDDED THUNDERSTORM
CANNOT BE RULED OUT. IN FACT...IF WE GET SOME CAPE WE COULD HAVE A
FEW STRONGER STORMS IN THE AFTERNOON INTO EARLY EVENING. AGAIN
CEILINGS PREDOMINATELY MVFR.
EXTENDED OUTLOOK...BECOMING VFR SATURDAY NIGHT. SLIGHT CHANCE FOR
SHOWERS AND MVFR CEILINGS OVER THE NORTHERN PORTION OF THE CWA.
OTHERWISE VFR THROUGH WEDNESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM FRIDAY...SOUTH WINDS SHOULD CONTINUE OVERNIGHT AS THE
CAROLINAS ARE IN BETWEEN HIGH PRESSURE WELL OFFSHORE AND AN
APPROACHING COLD FRONT OVER THE MISSISSIPPI VALLEY. THE GFS MODEL
HAS BEEN TOO STRONG WITH WIND SPEEDS ALL DAY...BUT A COMBINATION OF
THE 12Z NAM AND CANADIAN MODELS SEEMS LIKE A GOOD FIT. SOUTH WINDS
10-15 KNOTS WILL RAISE A SHORT-PERIOD WIND WAVE...BUT STRONGER WINDS
OFFSHORE WILL CREATE LARGER WAVES THAT WILL PUSH WESTWARD INTO THE
COASTAL WATERS AS WELL. THE COMBINATION SHOULD CREATE 4-6 FOOT SEAS
WITH A 6 SECOND DOMINANT PERIOD...AND A SMALL CRAFT ADVISORY WILL
REMAIN IN EFFECT FOR THIS. WAVES OF SHOWERS ARE EXPECTED ACROSS THE
WATERS...WITH HEAVIER ACTIVITY POSSIBLE OVERNIGHT. PM FRIDAY...
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300 PM FRIDAY...FAIRLY BRISK CONDITIONS WILL PREVAIL OVER THE
WATERS THROUGH THE PERIOD. FOR SATURDAY...A SOUTHERLY FLOW OF
15-20 KNOTS WILL BE IN PLACE AS LOW PRESSURE AND A COLD FRONT EDGE
CLOSER FROM THE WEST. THIS FRONT CROSSES THE WATERS BETWEEN 0600
AND 1200 UTC SUNDAY. WINDS WILL TURN FROM THE WEST AND INCREASE TO
20-25 KNOTS. WITH COLD AIR ADVECTION DEVELOPING SUNDAY...THE WINDS
WILL REMAIN ELEVATED BUT HOPEFULLY NOT THE LEVEL WE SAW EARLIER IN
THE WEEK TO GALE CRITERIA. BY MONDAY MORNING THERE IS A SLOW
DECREASE TO AROUND 15 KNOTS.
SIGNIFICANT SEAS WILL HOVER AROUND SMALL CRAFT CRITERIA AND I WILL
GO AHEAD AND EXTEND THE ADVISORY TO COVER SATURDAY AND SATURDAY
NIGHT. THE CHANGE IN FETCH SHOULD EVENTUALLY ALLOW THE ADVISORY TO
EXPIRE SUNDAY.
LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 300 PM FRIDAY...MONDAY STARTS WITH A MODERATE NW FLOW A RESULT
OF BOTH DEEPENING STORM MOVING UP THE MIDATLANTIC COAST AND HIGH
PRESSURE BUILDING IN FROM THE WEST. AS BOTH PROGRESS EASTWARD THE
LOCAL GRADIENT SHOULD REALLY EASE AS THE DAY WEARS ON AND BY MONDAY
NIGHT THERE MAY BE A LIGHT ENOUGH GRADIENT FOR A TRUE LIGHT AND
VARIABLE WIND. TUESDAY INTO WEDNESDAY THE HIGH TAKES A MORE OFFSHORE
POSITION GENERATING A LIGHT S TO SW FLOW LOCALLY. SEAS BUILD FROM
THEIR MINIMAL MONDAY NIGHT VALUES TO ABOUT 2 TO 3 FT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EDT SUNDAY FOR AMZ250-252-254-
256.
&&
$$
SYNOPSIS...SHK
NEAR TERM...TRA
SHORT TERM...SHK
LONG TERM...MBB
AVIATION...TRA/DL
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
128 PM EDT FRI MAR 28 2014
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE NORTHWEST LATER THIS AFTERNOON AND
THEN STALL TO THE NORTH TONIGHT. DEVELOPING LOW PRESSURE MOVING
ACROSS TO THE NORTH WILL PULL THE FRONT THROUGH THE AREA SATURDAY
NIGHT. THE LOW WILL CONTINUE DEEPENING AS IT MOVES TO THE
NORTHEAST SUNDAY AND SUNDAY NIGHT WITH HIGH PRESSURE BUILDING IN
FROM THE WEST THROUGH MONDAY. THE HIGH WILL MOVE SOUTH OF THE AREA
TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1 PM FRIDAY...HAVE AGAIN RAISED MAXIMUM TEMPERATURES A
COUPLE OF DEGREES AS MANY PLACES HAVE SOARED INTO THE LOWER 70S
AND MID 70S ARE NOT OUT OF THE QUESTION OVER THE NEXT COUPLE OF
HOURS. REMAINDER OF FORECAST REMAINS ON TRACK WITH SHOWERS
MOVING INTO THE FAR WESTERN COUNTIES AROUND 21Z OR SO BASED ON 4
KM NSSL WRF AND RAP MODELS. INSTABILITY LACKING AND DO NOT EXPECT
ANY THUNDER UNTIL SATURDAY AT THIS TIME.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
AS OF 430 AM FRIDAY...INCREASING MSTR AND SHRT WV ACTIVITY WILL
PRODUCE HIGHER THREAT OF SHOWERS TONIGHT...WITH TSTM MENTION LIMITED
TO COAST. GENERALLY CONTINUED PREVIOUS FCST OF POPS 50% COAST TO 70%
INLAND THIS EVENING...AND 60%-70% ALL ZONES OVERNIGHT. SRLY FLOW AND
CLOUD COVER WILL KEEP TEMPS MID 50S TO AROUND 60.
&&
.LONG TERM /SATURDAY THROUGH FRIDAY/...
AS OF 4 AM FRI...UNSETTLED PATTERN TO START THE LONG TERM PERIOD
THIS WEEKEND...THEN DRY AND SEASONABLY WARM FOR NEXT WEEK.
SHORT WAVE TROUGH ACROSS CENTRAL CONUS TODAY WILL AMPLIFY THROUGH
SATURDAY AND CLOSE OFF A MID LEVEL VORT SAT EVENING. MODELS COMING
IN BETTER AGREEMENT ON THIS SYNOPTIC SETUP AS WELL AS TIMING OF
THE FEATURES. THE NEUTRAL TILT CLOSED LOW WILL PROMOTE SFC LOW
DEVELOPMENT OVER CENTRAL NC SAT EVENING. AHEAD OF IT...INC SW LLJ
WILL FURTHER INC MOISTURE ADVECTION INTO E NC. BNDRY LAYER
STREAMLINES SUGGEST MOISTURE CONVERGENCE WILL BE MAXIMIZED SAT
EVENING...WITH BEST CHANCE OF WIDESPREAD RAIN SHOWERS OCCURRING
THEN. AHEAD OF THE SYSTEM...OCNL SHOWERS WITH EMBEDDED THUNDER
WILL OCCUR DURING THE DAY SAT. GFS ENSEMBLES CLUSTER FAIRLY WELL
WITH SFC LOW PLACEMENT ACROSS NC TO SOUTHERN VA BETWEEN 00Z AND
06Z SUN. THE 28/00Z ECM IS ALSO FAVORING THIS GENERAL POSITIONING
OF THE LOW. AS FAR AS SVR POTENTIAL IS CONCERNED...WIDESPREAD
CLOUDINESS AND RAIN SHOWER ACTIVITY WILL ACT TO LIMIT
DESTABILIZATION DURING THE DAY SAT...AND NOT EXPECTING MUCH IN WAY
OF ORGANIZED CONVECTION. NEVERTHELESS...BULK SHEAR WILL BE
SUFFICIENT FOR A FEW STORMS TO BECOME STRONG TO SEVERE WITH MAIN
THREAT ISOLATED DAMAGING WINDS. GFS AND NAM INDICATE SFC WINDS
BECOME BACKED SSE SAT EVENING AS H85-H90 FLOW REMAINS SW. THIS
WOULD PRODUCE FAIR AMOUNT OF LOW LEVEL TURNING/0-3KM HELICITY.
SHOULD ANY STORMS BECOME MORE ORGANIZED...CANNOT RULE OUT AN
ISOLATED TORNADO THREAT ESP LATE SAT AFTERNOON THROUGH EARLY
EVENING BEFORE LOW PULLS EAST AND SFC WINDS VEER SW TO W.
RAIN SHOWERS WILL DECREASE SAT NIGHT AS MOISTURE AND LIFT SHIFT
EAST WITH SFC EXITING SFC LOW. TEMPS WILL BE MILD MOST OF THE
NIGHT BEFORE WINDS BECOME W TO EVENTUALLY NW BY LATE SAT NIGHT AND
ALLOW TEMPS TO COOL TO THE LOW 50S. UPR LEVEL VORT WILL SLOWLY
MIGRATE EAST THROUGH THE DAY SUNDAY...AND HAVE CONTINUED TO WEIGHT
ECMWF SOLN WHICH WOULD KEEP WIDESPREAD LOW CLOUDS AND NUMEROUS
SHOWERS ACROSS E NC THROUGH THE FIRST HALF OF SUNDAY. HAVE INC
POPS TO LIKELY ACROSS THE NE ZONES...AND RETAINED HIGH CHANCE SCT
WORDING FURTHER S AND W. TEMPS WILL ALSO BE ON THE COOL SIDE WITH
THE WIDESPREAD CLOUDS AND SHOWER ACTIVITY WITH MOST AREAS IN THE
MID 50S...WITH SOME LOW 50S OBX.
DRAMATIC CLEARING OCCURS SUN NIGHT AS UPR LOW MOVES OUT TO SEA AND
TEMPS SEASONABLY COOL IN THE UPR 30S/LOW 40S FOR LOWS MON MORNING.
VERY DRY AIRMASS FOR MONDAY AS STRONG SUBSIDENCE AND BUILDING HIGH
PRES MOVE INTO THE AREA. 1000-850MB RH VALS PLUMMET TO THE 20%
RANGE ACCORDING TO THE ECM. WILL HAVE TO MONITOR FOR POTENTIAL
FIRE WEATHER CONCERNS. TEMPS WILL REBOUND TO THE MID/UPR 60S.
SPRAWLING SFC HIGH PRES WITH QUASI ZONAL FLOW WILL PRODUCE
PLEASANTLY DRY AND WARM CONDITIONS THROUGH THE MID WEEK TIME
PERIOD AND BEYOND WITH TEMPS WARMING TO THE MID/UPR 70S TO NEAR 80
BY THURSDAY. NEXT SYSTEM MAY AFFECT THE REGION FRIDAY INTO THE
WEEKEND.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH 18Z SATURDAY/...
AS OF 115 PM FRIDAY...VFR CONDITIONS WILL CONTINUE THROUGH THE
AFTERNOON WITH SUB-VFR FORECASTED THIS EVENING THROUGH TOMORROW.
A POTENT LOW PRESSURE SYSTEM WILL BE APPROACHING THE REGION FROM THE
WEST. THEREFORE...EXPECT CLOUDS TO INCREASE/LOW THROUGH THE LATE
AFTERNOON/EVENING HOURS. GUSTY SOUTHERLY FLOW WILL CONTINUE FOR THE
NEXT COUPLE OF HOURS BUT SUBSIDE AS THE SURFACE HEATING DIMINISHES.
RAIN SHOULD ARRIVE THIS EVENING THROUGH THE OVERNIGHT HOURS WITH
VSBYS LOWERING IN RESPONSE. ANTICIPATE MAINLY MVFR AND SOME PATCHY
IFR CIGS/VSBYS THROUGH THE OVERNIGHT HOURS INTO SATURDAY MORNING.
SSE WINDS AROUND 5-10KTS EXPECTED SATURDAY.
LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 4 AM FRI...MVFR OR LOWER IN NUMEROUS SHOWERS AND EMBEDDED
THUNDER SAT THROUGH SAT NIGHT. THE FRONT WILL MOVE OFF THE COAST
EARLY SUNDAY WITH SURFACE WINDS VEERING FROM SOUTH SOUTHWEST TO
NORTHWEST. SUB-VFR CONTINUES SUNDAY WITH SCATTERED TO NUMEROUS
SHOWERS IN LINGERING WRAPAROUND MOISTURE. VFR RETURNS ON SUN NIGHT
THROUGH MUCH OF NEXT WEEK AS LARGE HIGH PRES BUILDS IN BRINGING
EXCELLENT FLYING CONDITIONS.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 1 PM FRIDAY...SOUTHERLY WINDS ARE GRADUALLY INCREASING TO 15
TO 20 KNOTS ACROSS MOST OF THE WATERS AND SEAS ARE BUILDING WITH 6
FOOT NOW REPORTED AT DIAMOND BUOY. OTHER THAN BUMPING UP THE
INITIAL WINDS...NO BIG CHANGES TO THE MARINE FORECAST AT THIS
TIME.
LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 4 AM FRI...POOR BOATING CONDITIONS SAT THROUGH THE FIRST PART
OF NEXT WEEK. SW WINDS WILL INC ONCE AGAIN DURING THE DAY SAT TO 25
KT OR HIGHER...ESP THE SOUTHERN/CENTRAL WATERS...AND SEAS WILL INC
TO 6 FT OR HIGHER. THE S TO SW WINDS WILL REMAIN STRONG THROUGH SAT
EVENING AHEAD OF LOW PRES AND A COLD FRONT. THE LOW WILL MOVE
OFFSHORE WITH THE COLD FRONT LATE SAT NIGHT AND WINDS TURNING TO THE
W AND THEN NW BY SUN MORNING. THE OFFSHORE LOW WILL SLOWLY PUSH AWAY
AND KEEP THE NW GRADIENT RATHER STRONG WITH SCA CONTINUING THROUGH
THE DAY SUNDAY. WINDS WILL FINALLY DIMINISH ON MONDAY THOUGH
LINGERING LARGE SWELL ABOVE 6 FT WILL CONTINUE ESP ACROSS
NORTHERN/CENTRAL WATERS. CONDITIONS IMPROVE MON NIGHT AS GRADIENT
RELAXES. WINDS WILL TURN SW BUT REMAIN LIGHT TUE THROUGH MID WEEK AS
LARGE HIGH PRES MOVES TO THE SOUTH OF THE AREA. PLEASANT BOATING
CONDITIONS EXPECTED DURING THIS TIME FRAME.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT SATURDAY FOR AMZ152-154-
156-158.
&&
$$
SYNOPSIS...JBM
NEAR TERM...CTC
SHORT TERM...JBM
LONG TERM...TL
AVIATION...TL/LEP
MARINE...JBM/CTC/TL
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
102 PM EDT FRI MAR 28 2014
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE NORTHWEST LATER THIS AFTERNOON AND
THEN STALL TO THE NORTH TONIGHT. DEVELOPING LOW PRESSURE MOVING
ACROSS TO THE NORTH WILL PULL THE FRONT THROUGH THE AREA SATURDAY
NIGHT. THE LOW WILL CONTINUE DEEPENING AS IT MOVES TO THE
NORTHEAST SUNDAY AND SUNDAY NIGHT WITH HIGH PRESSURE BUILDING IN
FROM THE WEST THROUGH MONDAY. THE HIGH WILL MOVE SOUTH OF THE AREA
TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1 PM FRIDAY...HAVE AGAIN RAISED MAXIMUM TEMPERATURES A
COUPLE OF DEGREES AS MANY PLACES HAVE SOARED INTO THE LOWER 70S
AND MID 70S ARE NOT OUT OF THE QUESTION OVER THE NEXT COUPLE OF
HOURS. REMAINDER OF FORECAST REMAINS ON TRACK WITH SHOWERS
MOVING INTO THE FAR WESTERN COUNTIES AROUND 21Z OR SO BASED ON 4
KM NSSL WRF AND RAP MODELS. INSTABILITY LACKING AND DO NOT EXPECT
ANY THUNDER UNTIL SATURDAY AT THIS TIME.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
AS OF 430 AM FRIDAY...INCREASING MSTR AND SHRT WV ACTIVITY WILL
PRODUCE HIGHER THREAT OF SHOWERS TONIGHT...WITH TSTM MENTION LIMITED
TO COAST. GENERALLY CONTINUED PREVIOUS FCST OF POPS 50% COAST TO 70%
INLAND THIS EVENING...AND 60%-70% ALL ZONES OVERNIGHT. SRLY FLOW AND
CLOUD COVER WILL KEEP TEMPS MID 50S TO AROUND 60.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
AS OF 4 AM FRI...UNSETTLED PATTERN TO START THE LONG TERM PERIOD
THIS WEEKEND...THEN DRY AND SEASONABLY WARM FOR NEXT WEEK.
SHORT WAVE TROUGH ACROSS CENTRAL CONUS TODAY WILL AMPLIFY THROUGH
SATURDAY AND CLOSE OFF A MID LEVEL VORT SAT EVENING. MODELS COMING
IN BETTER AGREEMENT ON THIS SYNOPTIC SETUP AS WELL AS TIMING OF
THE FEATURES. THE NEUTRAL TILT CLOSED LOW WILL PROMOTE SFC LOW
DEVELOPMENT OVER CENTRAL NC SAT EVENING. AHEAD OF IT...INC SW LLJ
WILL FURTHER INC MOISTURE ADVECTION INTO E NC. BNDRY LAYER
STREAMLINES SUGGEST MOISTURE CONVERGENCE WILL BE MAXIMIZED SAT
EVENING...WITH BEST CHANCE OF WIDESPREAD RAIN SHOWERS OCCURRING
THEN. AHEAD OF THE SYSTEM...OCNL SHOWERS WITH EMBEDDED THUNDER
WILL OCCUR DURING THE DAY SAT. GFS ENSEMBLES CLUSTER FAIRLY WELL
WITH SFC LOW PLACEMENT ACROSS NC TO SOUTHERN VA BETWEEN 00Z AND
06Z SUN. THE 28/00Z ECM IS ALSO FAVORING THIS GENERAL POSITIONING
OF THE LOW. AS FAR AS SVR POTENTIAL IS CONCERNED...WIDESPREAD
CLOUDINESS AND RAIN SHOWER ACTIVITY WILL ACT TO LIMIT
DESTABILIZATION DURING THE DAY SAT...AND NOT EXPECTING MUCH IN WAY
OF ORGANIZED CONVECTION. NEVERTHELESS...BULK SHEAR WILL BE
SUFFICIENT FOR A FEW STORMS TO BECOME STRONG TO SEVERE WITH MAIN
THREAT ISOLATED DAMAGING WINDS. GFS AND NAM INDICATE SFC WINDS
BECOME BACKED SSE SAT EVENING AS H85-H90 FLOW REMAINS SW. THIS
WOULD PRODUCE FAIR AMOUNT OF LOW LEVEL TURNING/0-3KM HELICITY.
SHOULD ANY STORMS BECOME MORE ORGANIZED...CANNOT RULE OUT AN
ISOLATED TORNADO THREAT ESP LATE SAT AFTERNOON THROUGH EARLY
EVENING BEFORE LOW PULLS EAST AND SFC WINDS VEER SW TO W.
RAIN SHOWERS WILL DECREASE SAT NIGHT AS MOISTURE AND LIFT SHIFT
EAST WITH SFC EXITING SFC LOW. TEMPS WILL BE MILD MOST OF THE
NIGHT BEFORE WINDS BECOME W TO EVENTUALLY NW BY LATE SAT NIGHT AND
ALLOW TEMPS TO COOL TO THE LOW 50S. UPR LEVEL VORT WILL SLOWLY
MIGRATE EAST THROUGH THE DAY SUNDAY...AND HAVE CONTINUED TO WEIGHT
ECMWF SOLN WHICH WOULD KEEP WIDESPREAD LOW CLOUDS AND NUMEROUS
SHOWERS ACROSS E NC THROUGH THE FIRST HALF OF SUNDAY. HAVE INC
POPS TO LIKELY ACROSS THE NE ZONES...AND RETAINED HIGH CHANCE SCT
WORDING FURTHER S AND W. TEMPS WILL ALSO BE ON THE COOL SIDE WITH
THE WIDESPREAD CLOUDS AND SHOWER ACTIVITY WITH MOST AREAS IN THE
MID 50S...WITH SOME LOW 50S OBX.
DRAMATIC CLEARING OCCURS SUN NIGHT AS UPR LOW MOVES OUT TO SEA AND
TEMPS SEASONABLY COOL IN THE UPR 30S/LOW 40S FOR LOWS MON MORNING.
VERY DRY AIRMASS FOR MONDAY AS STRONG SUBSIDENCE AND BUILDING HIGH
PRES MOVE INTO THE AREA. 1000-850MB RH VALS PLUMMET TO THE 20%
RANGE ACCORDING TO THE ECM. WILL HAVE TO MONITOR FOR POTENTIAL
FIRE WEATHER CONCERNS. TEMPS WILL REBOUND TO THE MID/UPR 60S.
SPRAWLING SFC HIGH PRES WITH QUASI ZONAL FLOW WILL PRODUCE
PLEASANTLY DRY AND WARM CONDITIONS THROUGH THE MID WEEK TIME
PERIOD AND BEYOND WITH TEMPS WARMING TO THE MID/UPR 70S TO NEAR 80
BY THURSDAY. NEXT SYSTEM MAY AFFECT THE REGION FRIDAY INTO THE
WEEKEND.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH 12Z SATURDAY/...
AS OF 730 AM FRIDAY...VFR CONDITIONS WILL PREVAIL INTO THIS
AFTN...THEN MVFR CIGS/VSBYS EXPECTED WITH SHRA DURING EVENING
LINGERING INTO OVERNIGHT. PRE-FRONTAL WARM SECTOR CONDITIONS
EXPECTED DURING THE TAF PERIOD WITH HIGH PRES OFFSHORE AND COLD
FRONT APPROACHING FROM W. SCT-BKN SCU WILL DEVELOP THROUGH MORNING
HOURS WITH INCREASING SRLY FLOW BUT CIGS EXPECTED TO REMAIN ABOVE 3K
FT. ISOLD SHRA PSBL INLAND LATE MORNING BUT BETTER COVERAGE LIKELY
DURING AFTN AND EVENING WITH CIGS AND VSBYS LOWERING TO MVFR. MOIST
LOW LVLS WILL RESULT IN CIGS LOWERING TO AROUND 1K FT FOR INLAND
SITES OVERNIGHT. SRLY WINDS WILL GUST UP TO 20-25 KT THIS AFTN.
LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 4 AM FRI...MVFR OR LOWER IN NUMEROUS SHOWERS AND EMBEDDED
THUNDER SAT THROUGH SAT NIGHT. THE FRONT WILL MOVE OFF THE COAST
EARLY SUNDAY WITH SURFACE WINDS VEERING FROM SOUTH SOUTHWEST TO
NORTHWEST. SUB-VFR CONTINUES SUNDAY WITH SCATTERED TO NUMEROUS
SHOWERS IN LINGERING WRAPAROUND MOISTURE. VFR RETURNS ON SUN NIGHT
THROUGH MUCH OF NEXT WEEK AS LARGE HIGH PRES BUILDS IN BRINGING
EXCELLENT FLYING CONDITIONS.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 1 PM FRIDAY...SOUTHERLY WINDS ARE GRADUALLY INCREASING TO 15
TO 20 KNOTS ACROSS MOST OF THE WATERS AND SEAS ARE BUILDING WITH 6
FOOT NOW REPORTED AT DIAMOND BUOY. OTHER THAN BUMPING UP THE
INITIAL WINDS...NO BIG CHANGES TO THE MARINE FORECAST AT THIS
TIME.
LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 4 AM FRI...POOR BOATING CONDITIONS SAT THROUGH THE FIRST PART
OF NEXT WEEK. SW WINDS WILL INC ONCE AGAIN DURING THE DAY SAT TO 25
KT OR HIGHER...ESP THE SOUTHERN/CENTRAL WATERS...AND SEAS WILL INC
TO 6 FT OR HIGHER. THE S TO SW WINDS WILL REMAIN STRONG THROUGH SAT
EVENING AHEAD OF LOW PRES AND A COLD FRONT. THE LOW WILL MOVE
OFFSHORE WITH THE COLD FRONT LATE SAT NIGHT AND WINDS TURNING TO THE
W AND THEN NW BY SUN MORNING. THE OFFSHORE LOW WILL SLOWLY PUSH AWAY
AND KEEP THE NW GRADIENT RATHER STRONG WITH SCA CONTINUING THROUGH
THE DAY SUNDAY. WINDS WILL FINALLY DIMINISH ON MONDAY THOUGH
LINGERING LARGE SWELL ABOVE 6 FT WILL CONTINUE ESP ACROSS
NORTHERN/CENTRAL WATERS. CONDITIONS IMPROVE MON NIGHT AS GRADIENT
RELAXES. WINDS WILL TURN SW BUT REMAIN LIGHT TUE THROUGH MID WEEK AS
LARGE HIGH PRES MOVES TO THE SOUTH OF THE AREA. PLEASANT BOATING
CONDITIONS EXPECTED DURING THIS TIME FRAME.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT SATURDAY FOR AMZ152-154-
156-158.
&&
$$
SYNOPSIS...JBM
NEAR TERM...CTC
SHORT TERM...JBM
LONG TERM...TL
AVIATION...JBM/TL
MARINE...JBM/CTC/TL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1258 PM EDT FRI MAR 28 2014
.SYNOPSIS...
A COLD FRONT EXTENDING FROM THE GREAT LAKES INTO TEXAS WILL MOVE
INTO CAROLINAS EARLY SUNDAY MORNING. UNTIL THEN...RELATIVELY WARM
AND HUMID AIR WILL STREAM NORTHWARD...ACCOMPANIED BY PERIODS OF
SHOWERS AND THUNDERSTORMS. HIGH PRESSURE WILL FOLLOW THE COLD
FRONT...BRINGING COOLER TEMPERATURES SUNDAY AND MONDAY. THE CENTER
OF THE HIGH WILL MOVE OVERHEAD MONDAY NIGHT INTO TUESDAY.
TEMPERATURES SHOULD CLIMB WELL ABOVE NORMAL LATER NEXT WEEK. A COLD
FRONT MAY REACH THE AREA NEXT FRIDAY...BRINGING A RISK FOR SHOWERS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 100 PM FRIDAY...LIGHT SHOWERS HAVE DEVELOPED ALONG THE GENERAL
CORRIDOR INDICATED BY THE HRRR MODEL RUNS EARLIER THIS
MORNING...FROM GEORGETOWN THROUGH CONWAY...MARION AND DILLON. THIS
APPEARS TO BE THE PREFERRED AXIS FOR ADDITIONAL SHOWER DEVELOPMENT
THROUGH THE AFTERNOON...WITH LITTLE INDICATION SHOWER POTENTIAL WILL
RISE ACROSS THE WILMINGTON METRO AREA UNTIL PERHAPS NEAR SUNSET. A
LARGE AREA OF RAIN WITH EMBEDDED SHOWERY/CONVECTIVE ELEMENTS JUST
NOW CROSSING THE SAVANNAH RIVER INTO CENTRAL AND WESTERN SOUTH
CAROLINA WILL BEGIN TO IMPINGE ON OUR PEE DEE COUNTIES (FLORENCE AND
DARLINGTON) LATE THIS AFTERNOON...WITH SHOWER CHANCES INCREASING
RAPIDLY INTO THE EARLY EVENING HOURS. PREVIOUS DISCUSSION FROM 1030
AM FOLLOWS...
HIGH PRESSURE IS WELL OFFSHORE AND SOUTH WINDS ACROSS THE CAROLINAS
ARE BEING CAUSED BY RETURN FLOW BETWEEN THE HIGH AND A COLD FRONT
EXTENDING FROM THE GREAT LAKES INTO TEXAS. SUBTROPICAL MOISTURE
MOVING NORTHWARD IS SHOWING UP WITH CLIMBING SURFACE DEWPOINTS AND
PRECIPITABLE WATER VALUES...BOTH EXPECTED TO RISE SIGNIFICANTLY
TONIGHT.
AN AREA OF THICK MID AND HIGH CLOUDINESS ACROSS THE SOUTHEASTERN
STATES IS BEING PRODUCED BY A MESOSCALE CONVECTIVE SYSTEM ACROSS
MISSISSIPPI. SYNOPTIC MODELS ARE HAVING THEIR TROUBLE WITH THIS
SYSTEM...BUT THE LATEST FEW RUNS OF THE HRRR SHOW THE BULK OF THIS
CONVECTION DIMINISHING BEFORE ADVECTING THIS FAR EAST. INCREASING
MOISTURE SHOULD YIELD AN INCREASE IN SHOWER ACTIVITY LATE THIS
AFTERNOON ACROSS THE PEE DEE REGION...REACHING THE COAST AROUND
SUNSET OR SHORTLY THEREAFTER. A SECOND UNRELATED AREA OF SHOWERS
DEVELOPING ALONG THE GULF STREAM OFF THE GA/SC COAST IS STREAMING
NORTHWARD NEAR CHARLESTON AND GEORGETOWN...AND THREATENS TO BRING
SHOWERS ACROSS EASTERN SOUTH CAROLINA OVER THE NEXT SEVERAL HOURS.
POP/WX FORECASTS HAVE BEEN UPDATED TO FOCUS ON THESE TWO AREAS.
FEW CHANGES HAVE BEEN MADE TO FORECAST TEMPERATURES...STILL EXPECTED
TO REACH THE LOWER 70S FOR MOST AREAS AWAY FROM THE COOLING
INFLUENCE OF THE OCEAN.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300 AM FRIDAY...SURFACE LOW AND MID LEVEL TROUGH WILL BE WEST
OF THE AREA AT THE START OF THE PERIOD WITH THE REGION SOLIDLY IN
THE WARM SECTOR. SEVERAL FACTORS APPEAR TO BE IN PLACE SUPPORTING
CONVECTION SAT INTO SAT NIGHT. STRENGTHENING MID LEVEL SOUTHWEST
FLOW WILL CONTINUE TO PUMP MOISTURE INTO THE REGION. FORECAST
SOUNDINGS SHOW PRECIPITABLE WATER VALUES CLOSE TO 1.5 INCH. DIURNAL
INSTABILITY WILL ALSO BE PRESENT WITH HIGHS EXPECTED TO CLIMB INTO
THE LOWER 70S IN MOST AREAS. LOW LEVEL CONVERGENCE ALONG THE
RESULTANT SEA BREEZE MAY INITIATE CONVECTION IN THE AFTERNOON. ALOFT
THE APPROACHING 5H TROUGH WILL ENHANCE MID LEVEL LAPSE RATES BUT THE
UNKNOWN FACTOR AT THIS POINT REMAINS WHAT IMPACT POTENTIAL
CONVECTION IN THE NORTHEAST GULF OF MEXICO WILL HAVE ON INSTABILITY
SHOWERS/THUNDERSTORMS.
FARTHER WEST A LINE OF CONVECTION SHOULD BE DEVELOPING ASSOCIATED
WITH THE ADVANCING COLD FRONT. THIS LINE WILL MOVE INTO WHAT SHOULD
BE A MOIST/UNSTABLE ENVIRONMENT LATE SAT AND PUSH OFF THE COAST SAT
NIGHT. ALTHOUGH THE FRONT WILL HAVE PLENTY OF LOW LEVEL CONVERGENCE
AND MID LEVEL SUPPORT THERE IS SOME QUESTION AS TO THE STATE OF THE
ATMOSPHERE IT WILL BE MOVING INTO. THE CONVECTIVE LINE ASSOCIATED
WITH THE FRONT MAY END UP WEAKENING AS IT MOVES INTO THE REGION IF
EARLIER AFTERNOON CONVECTION IS MORE WIDESPREAD AND USES UP A LOT OF
THE AVAILABLE INSTABILITY. ON THE OTHER HAND SHOULD THE GULF
CONVECTION BE ABLE TO SUPPRESS MUCH OF THE ACTIVITY DURING THE FIRST
HALF OF SAT THE COLD FRONT WOULD HAVE PLENTY OF INSTABILITY TO WORK
WITH. SO IT IS NOT SO MUCH A QUESTION OF WILL IT RAIN...BUT MORE OF
A QUESTION OF WHEN WILL IT RAIN.
SEVERE WEATHER THREAT PERSISTS...ALTHOUGH WITH CAVEATS. LOW LEVEL
JETTING WILL BE WEAK FOR MUCH OF THE DAY BEFORE INCREASING TO 30 TO
35 KT JUST AHEAD OF THE FRONT. THE MAIN THREAT WOULD BE DAMAGING
WIND...ENHANCED BY STORMS MOVING CLOSE TO 30 MPH. IF STRONG/SEVERE
STORMS DEVELOP THEY ARE LIKELY TO DO SO WITH THE LINE OF CONVECTION
AHEAD OF THE FRONT...AGAIN ASSUMING DIURNAL DRIVEN CONVECTION IS
LIMITED IN SCOPE DURING THE DAY SAT.
COLD FRONT PUSHES OFF THE COAST LATE SAT NIGHT WITH THE MID LEVEL
TROUGH FOLLOWING ON SUN. COLD ADVECTION BEHIND THE FRONT WILL DROP
SUN TEMPS BELOW CLIMO...BUT COLD AIR WILL BE A LITTLE TOO LATE TO
HAVE A SIGNIFICANT IMPACT ON SAT NIGHT LOWS WHICH WILL END UP NEAR
TO SLIGHTLY ABOVE CLIMO. SUN SHOULD BE DRY WITH DEEP NORTHWEST FLOW
BEHIND THE TROUGH DROPPING PWATS UNDER .5 INCH FOR SUN AM AND UNDER
.25 INCH BY SUN EVENING. GRADIENT RELAXES SUN NIGHT BUT HIGH REMAINS
WEST OF THE AREA THROUGH THE END OF THE PERIOD SO SUN NIGHT WILL NOT
BE AN IDEAL RADIATIONAL COOLING NIGHT. STILL LOWS END UP BELOW CLIMO.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300 AM FRIDAY...LOW AMPLITUDE MID LEVEL RIDGING AND SPRAWLING
SURFACE HIGH WILL KEEP THE AREA DRY AND SEASONABLE THROUGH THE
PERIOD. COOLEST DAY WILL BE MON WITH SURFACE HIGH DIRECTLY OVERHEAD.
HIGH THEN DRIFTS OFFSHORE TUE THROUGH THU BRINGING SEVERAL DAYS OF
BEAUTIFUL SPRING WEATHER. PREVIOUSLY MEDIUM RANGE GUIDANCE HAD BEEN
MOVING A DRY COLD FRONT ACROSS THE AREA TUE NIGHT INTO WED. NOW THAT
GUIDANCE IS SUGGESTING MORE MID LEVEL AMPLIFICATION THIS SEEMS
UNLIKELY AND IN FACT THE 00Z GUIDANCE IS BACKING OFF ON THE DRY
FRONT. TEMPERATURES NEAR TO SLIGHTLY ABOVE CLIMO MON TRANSITION TO
ABOVE CLIMO MON NIGHT THROUGH THE END OF THE PERIOD.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 18Z...QUITE A BIT OF UNCERTAINTY WITH RESPECT TO THE TIMING OF
THE PRECIP...AS WELL AS CEILINGS OVERNIGHT. SOUTHERLY GRADIENT WILL
CAUSE WINDS TO GUSTS OVER 20 KTS AT TIMES...ESPECIALLY ALONG THE
COAST. SCATTERED SHOWERS WILL GIVE WAY TO MORE WIDESPREAD LIGHT TO
MODERATE RAIN THIS EVENING AS DEEP MOISTURE MOVES INTO THE REGION.
RAIN CHANCES WILL BE HIGHEST INLAND THIS EVENING...SPREADING TO THE
COAST A FEW HOURS LATER. CEILINGS ARE A BIT PROBLEMATIC...BUT WILL
GO FOR MVFR PREDOMINATELY WITH POCKETS OF IFR POSSIBLE. TIME HEIGHT
INDICATES THERE MAY BE A LULL IN THE PRECIP OF ABOUT 6-7 HOURS
THROUGH THE LATE OVERNIGHT HOURS. SATURDAY...MODERATE TO PERHAPS
HEAVY PRECIP SPREADING FROM WEST TO EAST. AN EMBEDDED THUNDERSTORM
CANNOT BE RULED OUT. IN FACT...IF WE GET SOME CAPE WE COULD HAVE A
FEW STRONGER STORMS IN THE AFTERNOON INTO EARLY EVENING. AGAIN
CEILINGS PREDOMINATELY MVFR.
EXTENDED OUTLOOK...BECOMING VFR SATURDAY NIGHT. SLIGHT CHANCE FOR
SHOWERS AND MVFR CEILINGS OVER THE NORTHERN PORTION OF THE CWA.
OTHERWISE VFR THROUGH WEDNESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 100 PM FRIDAY...NO SIGNIFICANT CHANGES HAVE BEEN MADE TO THE
FORECAST WITH THIS EARLY AFTERNOON UPDATE. PREVIOUS DISCUSSION FROM
1030 AM FOLLOWS...
HIGH PRESSURE THAT MOVED OFF THE NC COAST YESTERDAY IS NOW CROSSING
60 DEGREES WEST LONGITUDE AS IT CONTINUES TO PUT DISTANCE BETWEEN
ITSELF AND THE EAST COAST. LOW PRESSURE MOVING THROUGH THE GREAT
LAKES HAS A COLD FRONT EXTENDING SOUTH INTO TEXAS. THIS FRONT WILL
NOT ARRIVE UNTIL TOMORROW...ALLOWING SOUTHERLY WINDS AHEAD OF THE
FRONT TO CONTINUE ADVECTING A SUBTROPICAL AIRMASS ACROSS THE COASTAL
WATERS. AS DEWPOINTS INCREASE AND EXCEED THE NEARSHORE WATER
TEMPERATURES THERE IS AN INCREASING POTENTIAL FOR SEA FOG THIS
AFTERNOON AND TONIGHT...PARTICULARLY WITHIN 10 MILES OF SHORE WHERE
WATER TEMPERATURES ARE COLDEST.
SOUTH WINDS CURRENTLY AROUND 10-12 KNOTS SHOULD INCREASE A FEW MORE
KNOTS TODAY...BUT MAY ACTUALLY DIMINISH A LITTLE THIS EVENING AS AN
AREA OF DYING CONVECTION ARRIVES AND THE PRESSURE GRADIENT IS
DISRUPTED. REGARDLESS...WINDS SHOULD BUILD BACK UP TOWARD 12-15
KNOTS OVERNIGHT. SEAS ARE STILL A BIT HIGHER THAN WIND SPEEDS ALONE
WOULD SUGGEST...COURTESY OF THE HUGE LOW THAT MOVED NORTH THROUGH
THE WESTERN ATLANTIC A FEW DAYS AGO. AT THE FRYING PAN SHOALS BUOY
THERE IS STILL A SMALL 14 SECOND EAST SWELL PRESENT...WHICH WHEN
ADDED TO THE SHORTER 6-SECOND PERIOD WIND WAVES TOTALS AROUND 4
FEET. TOTAL SEAS EVEN INSIDE 20 MILES SHOULD INCREASE ON TOWARD 4-6
FEET BY THIS EVENING.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300 AM FRIDAY...SOUTHERLY FLOW WILL APPROACH 20 KT SAT AS
GRADIENT OVER THE WATERS IS PINCHED BETWEEN ADVANCING COLD FRONT AND
HIGH PRESSURE. ANTICIPATE A LINE OF CONVECTION AHEAD OF THE FRONT
WHICH WILL CROSS THE WATERS SAT EVE/NIGHT. OFFSHORE FLOW DEVELOPS
BEHIND THE FRONT WITH GRADIENT AND DEVELOPING COLD ADVECTION KEEPING
SPEEDS AROUND 20 KT. LITTLE CHANGE IN THE GRADIENT SUN AS HIGH
BUILDS KEEPS NORTHWEST WINDS A SOLID 20 KT FOR MUCH OF THE DAY.
OFFSHORE FLOW SLOWLY WEAKENS SUN NIGHT...DROPPING TO 15 KT BY THE
END OF THE PERIOD...AS GRADIENT RELAXES. SEAS 4 TO 6 FT EXPECTED SAT
INTO SUN WHEN OFFSHORE COMPONENT DROPS SEAS TO 3 TO 5 FT. CONTINUED
OFFSHORE FLOW COMBINED WITH REDUCTION IN SPEEDS SUN NIGHT WILL DROP
SEAS TO 2 TO 4 FT BY THE END OF THE PERIOD.
LONG TERM /MONDAY THROUGH TUESDAY/...
AS OF 300 AM FRIDAY...OFFSHORE FLOW AROUND 15 KT AT THE START OF THE
PERIOD WILL DECREASE DURING MON AS HIGH PRESSURE MOVES OVER HEAD.
SPEEDS WILL DROP UNDER 10 KT BY MON EVENING...BECOMING LIGHT AND
VARIABLE MON NIGHT. HIGH SHIFTS OFFSHORE FOR TUE WITH RETURN FLOW
SLOWLY RISING INTO THE 10 TO 15 KT RANGE LATE TUE AND TUE NIGHT.
SEAS WILL RUN 2 TO 3 FT FOR A MAJORITY OF THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 8 AM EDT
SATURDAY FOR AMZ250-252-254-256.
&&
$$
NEAR TERM...TRA
SHORT TERM...III
LONG TERM...III
AVIATION...HDL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1058 AM EDT FRI MAR 28 2014
.SYNOPSIS...
A COLD FRONT EXTENDING FROM THE GREAT LAKES INTO TEXAS WILL MOVE
INTO CAROLINAS EARLY SUNDAY MORNING. UNTIL THEN...RELATIVELY WARM
AND HUMID AIR WILL STREAM NORTHWARD...ACCOMPANIED BY PERIODS OF
SHOWERS AND THUNDERSTORMS. HIGH PRESSURE WILL FOLLOW THE COLD
FRONT...BRINGING COOLER TEMPERATURES SUNDAY AND MONDAY. THE CENTER
OF THE HIGH WILL MOVE OVERHEAD MONDAY NIGHT INTO TUESDAY.
TEMPERATURES SHOULD CLIMB WELL ABOVE NORMAL LATER NEXT WEEK. A COLD
FRONT MAY REACH THE AREA NEXT FRIDAY...BRINGING A RISK FOR SHOWERS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM FRIDAY...HIGH PRESSURE IS WELL OFFSHORE AND SOUTH
WINDS ACROSS THE CAROLINAS ARE BEING CAUSED BY RETURN FLOW BETWEEN
THE HIGH AND A COLD FRONT EXTENDING FROM THE GREAT LAKES INTO TEXAS.
SUBTROPICAL MOISTURE MOVING NORTHWARD IS SHOWING UP WITH CLIMBING
SURFACE DEWPOINTS AND PRECIPITABLE WATER VALUES...BOTH EXPECTED TO
RISE SIGNIFICANTLY TONIGHT.
AN AREA OF THICK MID AND HIGH CLOUDINESS ACROSS THE SOUTHEASTERN
STATES IS BEING PRODUCED BY A MESOSCALE CONVECTIVE SYSTEM ACROSS
MISSISSIPPI. SYNOPTIC MODELS ARE HAVING THEIR TROUBLE WITH THIS
SYSTEM...BUT THE LATEST FEW RUNS OF THE HRRR SHOW THE BULK OF THIS
CONVECTION DIMINISHING BEFORE ADVECTING THIS FAR EAST. INCREASING
MOISTURE SHOULD YIELD AN INCREASE IN SHOWER ACTIVITY LATE THIS
AFTERNOON ACROSS THE PEE DEE REGION...REACHING THE COAST AROUND
SUNSET OR SHORTLY THEREAFTER. A SECOND UNRELATED AREA OF SHOWERS
DEVELOPING ALONG THE GULF STREAM OFF THE GA/SC COAST IS STREAMING
NORTHWARD NEAR CHARLESTON AND GEORGETOWN...AND THREATENS TO BRING
SHOWERS ACROSS EASTERN SOUTH CAROLINA OVER THE NEXT SEVERAL HOURS.
POP/WX FORECASTS HAVE BEEN UPDATED TO FOCUS ON THESE TWO AREAS.
FEW CHANGES HAVE BEEN MADE TO FORECAST TEMPERATURES...STILL EXPECTED
TO REACH THE LOWER 70S FOR MOST AREAS AWAY FROM THE COOLING
INFLUENCE OF THE OCEAN.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300 AM FRIDAY...SURFACE LOW AND MID LEVEL TROUGH WILL BE WEST
OF THE AREA AT THE START OF THE PERIOD WITH THE REGION SOLIDLY IN
THE WARM SECTOR. SEVERAL FACTORS APPEAR TO BE IN PLACE SUPPORTING
CONVECTION SAT INTO SAT NIGHT. STRENGTHENING MID LEVEL SOUTHWEST
FLOW WILL CONTINUE TO PUMP MOISTURE INTO THE REGION. FORECAST
SOUNDINGS SHOW PRECIPITABLE WATER VALUES CLOSE TO 1.5 INCH. DIURNAL
INSTABILITY WILL ALSO BE PRESENT WITH HIGHS EXPECTED TO CLIMB INTO
THE LOWER 70S IN MOST AREAS. LOW LEVEL CONVERGENCE ALONG THE
RESULTANT SEA BREEZE MAY INITIATE CONVECTION IN THE AFTERNOON. ALOFT
THE APPROACHING 5H TROUGH WILL ENHANCE MID LEVEL LAPSE RATES BUT THE
UNKNOWN FACTOR AT THIS POINT REMAINS WHAT IMPACT POTENTIAL
CONVECTION IN THE NORTHEAST GULF OF MEXICO WILL HAVE ON INSTABILITY
SHOWERS/THUNDERSTORMS.
FARTHER WEST A LINE OF CONVECTION SHOULD BE DEVELOPING ASSOCIATED
WITH THE ADVANCING COLD FRONT. THIS LINE WILL MOVE INTO WHAT SHOULD
BE A MOIST/UNSTABLE ENVIRONMENT LATE SAT AND PUSH OFF THE COAST SAT
NIGHT. ALTHOUGH THE FRONT WILL HAVE PLENTY OF LOW LEVEL CONVERGENCE
AND MID LEVEL SUPPORT THERE IS SOME QUESTION AS TO THE STATE OF THE
ATMOSPHERE IT WILL BE MOVING INTO. THE CONVECTIVE LINE ASSOCIATED
WITH THE FRONT MAY END UP WEAKENING AS IT MOVES INTO THE REGION IF
EARLIER AFTERNOON CONVECTION IS MORE WIDESPREAD AND USES UP A LOT OF
THE AVAILABLE INSTABILITY. ON THE OTHER HAND SHOULD THE GULF
CONVECTION BE ABLE TO SUPPRESS MUCH OF THE ACTIVITY DURING THE FIRST
HALF OF SAT THE COLD FRONT WOULD HAVE PLENTY OF INSTABILITY TO WORK
WITH. SO IT IS NOT SO MUCH A QUESTION OF WILL IT RAIN...BUT MORE OF
A QUESTION OF WHEN WILL IT RAIN.
SEVERE WEATHER THREAT PERSISTS...ALTHOUGH WITH CAVEATS. LOW LEVEL
JETTING WILL BE WEAK FOR MUCH OF THE DAY BEFORE INCREASING TO 30 TO
35 KT JUST AHEAD OF THE FRONT. THE MAIN THREAT WOULD BE DAMAGING
WIND...ENHANCED BY STORMS MOVING CLOSE TO 30 MPH. IF STRONG/SEVERE
STORMS DEVELOP THEY ARE LIKELY TO DO SO WITH THE LINE OF CONVECTION
AHEAD OF THE FRONT...AGAIN ASSUMING DIURNAL DRIVEN CONVECTION IS
LIMITED IN SCOPE DURING THE DAY SAT.
COLD FRONT PUSHES OFF THE COAST LATE SAT NIGHT WITH THE MID LEVEL
TROUGH FOLLOWING ON SUN. COLD ADVECTION BEHIND THE FRONT WILL DROP
SUN TEMPS BELOW CLIMO...BUT COLD AIR WILL BE A LITTLE TOO LATE TO
HAVE A SIGNIFICANT IMPACT ON SAT NIGHT LOWS WHICH WILL END UP NEAR
TO SLIGHTLY ABOVE CLIMO. SUN SHOULD BE DRY WITH DEEP NORTHWEST FLOW
BEHIND THE TROUGH DROPPING PWATS UNDER .5 INCH FOR SUN AM AND UNDER
.25 INCH BY SUN EVENING. GRADIENT RELAXES SUN NIGHT BUT HIGH REMAINS
WEST OF THE AREA THROUGH THE END OF THE PERIOD SO SUN NIGHT WILL NOT
BE AN IDEAL RADIATIONAL COOLING NIGHT. STILL LOWS END UP BELOW CLIMO.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300 AM FRIDAY...LOW AMPLITUDE MID LEVEL RIDGING AND SPRAWLING
SURFACE HIGH WILL KEEP THE AREA DRY AND SEASONABLE THROUGH THE
PERIOD. COOLEST DAY WILL BE MON WITH SURFACE HIGH DIRECTLY OVERHEAD.
HIGH THEN DRIFTS OFFSHORE TUE THROUGH THU BRINGING SEVERAL DAYS OF
BEAUTIFUL SPRING WEATHER. PREVIOUSLY MEDIUM RANGE GUIDANCE HAD BEEN
MOVING A DRY COLD FRONT ACROSS THE AREA TUE NIGHT INTO WED. NOW THAT
GUIDANCE IS SUGGESTING MORE MID LEVEL AMPLIFICATION THIS SEEMS
UNLIKELY AND IN FACT THE 00Z GUIDANCE IS BACKING OFF ON THE DRY
FRONT. TEMPERATURES NEAR TO SLIGHTLY ABOVE CLIMO MON TRANSITION TO
ABOVE CLIMO MON NIGHT THROUGH THE END OF THE PERIOD.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 12Z...RETURN FLOW WILL COMMENCE SHORTLY. HAVE LEANED FAIRLY
HEAVILY ON THE HRRR EARLY...WITH SHOWERS POPPING UP ALONG THE
MYRTLES BY LATE MORNING. INCREASING SOUTHERLY GRADIENT WILL CAUSE
WINDS TO GUSTS OVER 20 KTS AT TIMES...ESPECIALLY ALONG THE COAST.
SCATTERED SHOWERS WILL GIVE WAY TO MORE WIDESPREAD RAIN THIS EVENING
AS DEEP MOISTURE MOVES INTO THE REGION. RAIN CHANCES WILL BE HIGHEST
INLAND THIS EVENING...SPREADING TO THE COAST A FEW HOURS LATER.
CEILINGS ARE A BIT PROBLEMATIC...BUT WILL GO FOR MVFR PREDOMINATELY
WITH POCKETS OF IFR POSSIBLE.
EXTENDED OUTLOOK...SHOWERS AND T-STORMS WITH MVFR/TEMPO IFR
CONDITIONS OVERNIGHT AND ON SATURDAY. VFR SUNDAY THROUGH TUESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM FRIDAY...HIGH PRESSURE THAT MOVED OFF THE NC COAST
YESTERDAY IS NOW CROSSING 60 DEGREES WEST LONGITUDE AS IT CONTINUES
TO PUT DISTANCE BETWEEN ITSELF AND THE EAST COAST. LOW PRESSURE
MOVING THROUGH THE GREAT LAKES HAS A COLD FRONT EXTENDING SOUTH INTO
TEXAS. THIS FRONT WILL NOT ARRIVE UNTIL TOMORROW...ALLOWING
SOUTHERLY WINDS AHEAD OF THE FRONT TO CONTINUE ADVECTING A
SUBTROPICAL AIRMASS ACROSS THE COASTAL WATERS. AS DEWPOINTS INCREASE
AND EXCEED THE NEARSHORE WATER TEMPERATURES THERE IS AN INCREASING
POTENTIAL FOR SEA FOG THIS AFTERNOON AND TONIGHT...PARTICULARLY
WITHIN 10 MILES OF SHORE WHERE WATER TEMPERATURES ARE COLDEST.
SOUTH WINDS CURRENTLY AROUND 10-12 KNOTS SHOULD INCREASE A FEW MORE
KNOTS TODAY...BUT MAY ACTUALLY DIMINISH A LITTLE THIS EVENING AS AN
AREA OF DYING CONVECTION ARRIVES AND THE PRESSURE GRADIENT IS
DISRUPTED. REGARDLESS...WINDS SHOULD BUILD BACK UP TOWARD 12-15
KNOTS OVERNIGHT. SEAS ARE STILL A BIT HIGHER THAN WIND SPEEDS ALONE
WOULD SUGGEST...COURTESY OF THE HUGE LOW THAT MOVED NORTH THROUGH
THE WESTERN ATLANTIC A FEW DAYS AGO. AT THE FRYING PAN SHOALS BUOY
THERE IS STILL A SMALL 14 SECOND EAST SWELL PRESENT...WHICH WHEN
ADDED TO THE SHORTER 6-SECOND PERIOD WIND WAVES TOTALS AROUND 4
FEET. TOTAL SEAS EVEN INSIDE 20 MILES SHOULD INCREASE ON TOWARD 4-6
FEET BY THIS EVENING.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300 AM FRIDAY...SOUTHERLY FLOW WILL APPROACH 20 KT SAT AS
GRADIENT OVER THE WATERS IS PINCHED BETWEEN ADVANCING COLD FRONT AND
HIGH PRESSURE. ANTICIPATE A LINE OF CONVECTION AHEAD OF THE FRONT
WHICH WILL CROSS THE WATERS SAT EVE/NIGHT. OFFSHORE FLOW DEVELOPS
BEHIND THE FRONT WITH GRADIENT AND DEVELOPING COLD ADVECTION KEEPING
SPEEDS AROUND 20 KT. LITTLE CHANGE IN THE GRADIENT SUN AS HIGH
BUILDS KEEPS NORTHWEST WINDS A SOLID 20 KT FOR MUCH OF THE DAY.
OFFSHORE FLOW SLOWLY WEAKENS SUN NIGHT...DROPPING TO 15 KT BY THE
END OF THE PERIOD...AS GRADIENT RELAXES. SEAS 4 TO 6 FT EXPECTED SAT
INTO SUN WHEN OFFSHORE COMPONENT DROPS SEAS TO 3 TO 5 FT. CONTINUED
OFFSHORE FLOW COMBINED WITH REDUCTION IN SPEEDS SUN NIGHT WILL DROP
SEAS TO 2 TO 4 FT BY THE END OF THE PERIOD.
LONG TERM /MONDAY THROUGH TUESDAY/...
AS OF 300 AM FRIDAY...OFFSHORE FLOW AROUND 15 KT AT THE START OF THE
PERIOD WILL DECREASE DURING MON AS HIGH PRESSURE MOVES OVER HEAD.
SPEEDS WILL DROP UNDER 10 KT BY MON EVENING...BECOMING LIGHT AND
VARIABLE MON NIGHT. HIGH SHIFTS OFFSHORE FOR TUE WITH RETURN FLOW
SLOWLY RISING INTO THE 10 TO 15 KT RANGE LATE TUE AND TUE NIGHT.
SEAS WILL RUN 2 TO 3 FT FOR A MAJORITY OF THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 8 AM EDT
SATURDAY FOR AMZ250-252-254-256.
&&
$$
NEAR TERM...TRA
SHORT TERM...III
LONG TERM...III
AVIATION...SGL/RJD
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
953 AM EDT FRI MAR 28 2014
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE NORTHWEST LATER TODAY AND THEN
STALL TO THE NORTH TONIGHT. DEVELOPING LOW PRESSURE MOVING ACROSS TO
THE NORTH WILL PULL THE FRONT THROUGH THE AREA SATURDAY NIGHT. THE
LOW WILL CONTINUE DEEPENING AS IT MOVES TO THE NORTHEAST SUNDAY AND
SUNDAY NIGHT WITH HIGH PRESSURE BUILDING IN FROM THE WEST THROUGH
MONDAY. THE HIGH WILL MOVE SOUTH OF THE AREA TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 945 AM FRIDAY...TEMPERATURES HAVE WARMED VERY QUICKLY THIS
MORNING WITH MOST AREAS ALREADY WELL INTO THE 60S. AS A
RESULT...HAVE RAISED MAXIMUM TEMPERATURES A COUPLE OF
DEGREES...ESPECIALLY ALONG THE SOUTH COAST. CLOUDS WILL CONTINUE
TO INCREASE DURING THE AFTERNOON...BUT RAP AND 4KM WRF MODELS HOLD
OFF ANY PRECIPITATION UNTIL AFTER 21Z OVER THE WESTERN COASTAL
PLAINS COUNTIES. EXPECT A BROKEN LINE OF SHOWERS...BUT INSTABILITY
WILL BE MARGINAL FOR ANY THUNDER LATE THIS AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
AS OF 430 AM FRIDAY...INCREASING MSTR AND SHRT WV ACTIVITY WILL
PRODUCE HIGHER THREAT OF SHOWERS TONIGHT...WITH TSTM MENTION LIMITED
TO COAST. GENERALLY CONTINUED PREVIOUS FCST OF POPS 50% COAST TO 70%
INLAND THIS EVENING...AND 60%-70% ALL ZONES OVERNIGHT. SRLY FLOW AND
CLOUD COVER WILL KEEP TEMPS MID 50S TO AROUND 60.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
AS OF 4 AM FRI...UNSETTLED PATTERN TO START THE LONG TERM PERIOD
THIS WEEKEND...THEN DRY AND SEASONABLY WARM FOR NEXT WEEK.
SHORT WAVE TROUGH ACROSS CENTRAL CONUS TODAY WILL AMPLIFY THROUGH
SATURDAY AND CLOSE OFF A MID LEVEL VORT SAT EVENING. MODELS COMING
IN BETTER AGREEMENT ON THIS SYNOPTIC SETUP AS WELL AS TIMING OF
THE FEATURES. THE NEUTRAL TILT CLOSED LOW WILL PROMOTE SFC LOW
DEVELOPMENT OVER CENTRAL NC SAT EVENING. AHEAD OF IT...INC SW LLJ
WILL FURTHER INC MOISTURE ADVECTION INTO E NC. BNDRY LAYER
STREAMLINES SUGGEST MOISTURE CONVERGENCE WILL BE MAXIMIZED SAT
EVENING...WITH BEST CHANCE OF WIDESPREAD RAIN SHOWERS OCCURRING
THEN. AHEAD OF THE SYSTEM...OCNL SHOWERS WITH EMBEDDED THUNDER
WILL OCCUR DURING THE DAY SAT. GFS ENSEMBLES CLUSTER FAIRLY WELL
WITH SFC LOW PLACEMENT ACROSS NC TO SOUTHERN VA BETWEEN 00Z AND
06Z SUN. THE 28/00Z ECM IS ALSO FAVORING THIS GENERAL POSITIONING
OF THE LOW. AS FAR AS SVR POTENTIAL IS CONCERNED...WIDESPREAD
CLOUDINESS AND RAIN SHOWER ACTIVITY WILL ACT TO LIMIT
DESTABILIZATION DURING THE DAY SAT...AND NOT EXPECTING MUCH IN WAY
OF ORGANIZED CONVECTION. NEVERTHELESS...BULK SHEAR WILL BE
SUFFICIENT FOR A FEW STORMS TO BECOME STRONG TO SEVERE WITH MAIN
THREAT ISOLATED DAMAGING WINDS. GFS AND NAM INDICATE SFC WINDS
BECOME BACKED SSE SAT EVENING AS H85-H90 FLOW REMAINS SW. THIS
WOULD PRODUCE FAIR AMOUNT OF LOW LEVEL TURNING/0-3KM HELICITY.
SHOULD ANY STORMS BECOME MORE ORGANIZED...CANNOT RULE OUT AN
ISOLATED TORNADO THREAT ESP LATE SAT AFTERNOON THROUGH EARLY
EVENING BEFORE LOW PULLS EAST AND SFC WINDS VEER SW TO W.
RAIN SHOWERS WILL DECREASE SAT NIGHT AS MOISTURE AND LIFT SHIFT
EAST WITH SFC EXITING SFC LOW. TEMPS WILL BE MILD MOST OF THE
NIGHT BEFORE WINDS BECOME W TO EVENTUALLY NW BY LATE SAT NIGHT AND
ALLOW TEMPS TO COOL TO THE LOW 50S. UPR LEVEL VORT WILL SLOWLY
MIGRATE EAST THROUGH THE DAY SUNDAY...AND HAVE CONTINUED TO WEIGHT
ECMWF SOLN WHICH WOULD KEEP WIDESPREAD LOW CLOUDS AND NUMEROUS
SHOWERS ACROSS E NC THROUGH THE FIRST HALF OF SUNDAY. HAVE INC
POPS TO LIKELY ACROSS THE NE ZONES...AND RETAINED HIGH CHANCE SCT
WORDING FURTHER S AND W. TEMPS WILL ALSO BE ON THE COOL SIDE WITH
THE WIDESPREAD CLOUDS AND SHOWER ACTIVITY WITH MOST AREAS IN THE
MID 50S...WITH SOME LOW 50S OBX.
DRAMATIC CLEARING OCCURS SUN NIGHT AS UPR LOW MOVES OUT TO SEA AND
TEMPS SEASONABLY COOL IN THE UPR 30S/LOW 40S FOR LOWS MON MORNING.
VERY DRY AIRMASS FOR MONDAY AS STRONG SUBSIDENCE AND BUILDING HIGH
PRES MOVE INTO THE AREA. 1000-850MB RH VALS PLUMMET TO THE 20%
RANGE ACCORDING TO THE ECM. WILL HAVE TO MONITOR FOR POTENTIAL
FIRE WEATHER CONCERNS. TEMPS WILL REBOUND TO THE MID/UPR 60S.
SPRAWLING SFC HIGH PRES WITH QUASI ZONAL FLOW WILL PRODUCE
PLEASANTLY DRY AND WARM CONDITIONS THROUGH THE MID WEEK TIME
PERIOD AND BEYOND WITH TEMPS WARMING TO THE MID/UPR 70S TO NEAR 80
BY THURSDAY. NEXT SYSTEM MAY AFFECT THE REGION FRIDAY INTO THE
WEEKEND.
&&
.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
SHORT TERM /THROUGH 12Z SATURDAY/...
AS OF 730 AM FRIDAY...VFR CONDITIONS WILL PREVAIL INTO THIS
AFTN...THEN MVFR CIGS/VSBYS EXPECTED WITH SHRA DURING EVENING
LINGERING INTO OVERNIGHT. PRE-FRONTAL WARM SECTOR CONDITIONS
EXPECTED DURING THE TAF PERIOD WITH HIGH PRES OFFSHORE AND COLD
FRONT APPROACHING FROM W. SCT-BKN SCU WILL DEVELOP THROUGH MORNING
HOURS WITH INCREASING SRLY FLOW BUT CIGS EXPECTED TO REMAIN ABOVE 3K
FT. ISOLD SHRA PSBL INLAND LATE MORNING BUT BETTER COVERAGE LIKELY
DURING AFTN AND EVENING WITH CIGS AND VSBYS LOWERING TO MVFR. MOIST
LOW LVLS WILL RESULT IN CIGS LOWERING TO AROUND 1K FT FOR INLAND
SITES OVERNIGHT. SRLY WINDS WILL GUST UP TO 20-25 KT THIS AFTN.
LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 4 AM FRI...MVFR OR LOWER IN NUMEROUS SHOWERS AND EMBEDDED
THUNDER SAT THROUGH SAT NIGHT. THE FRONT WILL MOVE OFF THE COAST
EARLY SUNDAY WITH SURFACE WINDS VEERING FROM SOUTH SOUTHWEST TO
NORTHWEST. SUB-VFR CONTINUES SUNDAY WITH SCATTERED TO NUMEROUS
SHOWERS IN LINGERING WRAPAROUND MOISTURE. VFR RETURNS ON SUN NIGHT
THROUGH MUCH OF NEXT WEEK AS LARGE HIGH PRES BUILDS IN BRINGING
EXCELLENT FLYING CONDITIONS.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 955 AM FRIDAY...TIGHTENING PRES GRAD EXPECTED TO PRODUCE
15-20 KT WINDS OVER NEAR SHORE WATERS DURING THE AFTERNOON...WITH SEAS
BUILDING TO 4-6 FT SRN WATERS...THUS CONTINUED SCA. WINDS WILL
DIMINISH THIS EVENING AS GRADIENT WEAKENS...AND SEAS FALLING BELOW
6 FT AGAIN LATE TONIGHT.
LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 4 AM FRI...POOR BOATING CONDITIONS SAT THROUGH THE FIRST PART
OF NEXT WEEK. SW WINDS WILL INC ONCE AGAIN DURING THE DAY SAT TO 25
KT OR HIGHER...ESP THE SOUTHERN/CENTRAL WATERS...AND SEAS WILL INC
TO 6 FT OR HIGHER. THE S TO SW WINDS WILL REMAIN STRONG THROUGH SAT
EVENING AHEAD OF LOW PRES AND A COLD FRONT. THE LOW WILL MOVE
OFFSHORE WITH THE COLD FRONT LATE SAT NIGHT AND WINDS TURNING TO THE
W AND THEN NW BY SUN MORNING. THE OFFSHORE LOW WILL SLOWLY PUSH AWAY
AND KEEP THE NW GRADIENT RATHER STRONG WITH SCA CONTINUING THROUGH
THE DAY SUNDAY. WINDS WILL FINALLY DIMINISH ON MONDAY THOUGH
LINGERING LARGE SWELL ABOVE 6 FT WILL CONTINUE ESP ACROSS
NORTHERN/CENTRAL WATERS. CONDITIONS IMPROVE MON NIGHT AS GRADIENT
RELAXES. WINDS WILL TURN SW BUT REMAIN LIGHT TUE THROUGH MID WEEK AS
LARGE HIGH PRES MOVES TO THE SOUTH OF THE AREA. PLEASANT BOATING
CONDITIONS EXPECTED DURING THIS TIME FRAME.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT SATURDAY FOR AMZ152-154.
SMALL CRAFT ADVISORY UNTIL 2 AM EDT SATURDAY FOR AMZ156-158.
&&
$$
SYNOPSIS...JBM
NEAR TERM...CTC
SHORT TERM...JBM
LONG TERM...TL
AVIATION...JBM/TL
MARINE...JBM/CTC/TL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
654 AM EDT FRI MAR 28 2014
.SYNOPSIS...
MUCH MORE MOIST AND WARMER AIR WILL BE IN PLACE AHEAD OF A COLD
FRONT APPROACHING FROM THE WEST. THE FRONT WILL MOVE ACROSS THE AREA
SATURDAY NIGHT. THE RISK FOR SHOWERS AND THUNDERSTORMS WILL BE ON
THE INCREASE UNTIL PASSAGE OF THE COLD FRONT. SOME STORMS MAY BE
STRONG TO SEVERE SATURDAY AND SATURDAY NIGHT. A BRIEF COOL DOWN WILL
OCCUR BEHIND THE FRONT SUNDAY. HIGH PRESSURE NEXT WEEK WILL BRING
DRY WEATHER WITH TEMPERATURES CLIMBING WELL ABOVE NORMAL. A COLD
FRONT MAY REACH THE AREA NEXT FRIDAY...BRINGING A RISK FOR SHOWERS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 600 AM FRIDAY...RETURN FLOW AROUND DEPARTING HIGH PRESSURE HAS
TAKEN A FIRM HOLD ON THE AREA AND WE ARE BEGINNING TO SEE DEWPOINTS
SURGE HIGHER...NOW UP TO THE MID AND UPPER 40S ALONG THE COAST...AND
IN THE LOWER 40S FOR MOST INLAND LOCATIONS. TEMPS HAVE ALSO RISEN
WITH THE APPROACH OF MORNING...IN THE MID AND UPPER 40S IN MOST
LOCATIONS...TOPPING 50 DEGREES IN SOME COASTAL AREAS.
DEEP S TO SW FLOW WILL BE IN PLACE THIS PERIOD AND THIS WILL BRING
INCREASING MOISTURE AND TEMPERATURE WHICH WILL RESULT IN INCREASED
INSTABILITY. PRECIPITABLE WATER VALUES WILL BE NEAR 1 INCH THIS
MORNING...CLIMBING TO 1.25 TO 1.5 INCHES LATER TODAY AND TONIGHT.
THE COLUMN SUFFICIENTLY SATURATES TO A DEPTH THAT DOES SUPPORT
MEASURABLE PRECIPITATION. SHORTWAVE ENERGY IN THE MID LEVELS DOES
APPROACH FROM THE W TODAY AND THEN ACROSS THE AREA TONIGHT. THERE IS
SOME INDICATION THE ENERGY MAY SPLIT...WITH THE FORECAST AREA LYING
IN BETWEEN THE BEST UPPER LEVEL SUPPORT. THERE IS ALSO SOME CONCERN
THAT WIDESPREAD CONVECTION ALONG THE GULF COAST MAY SERVE TO ROB OR
AT LEAST DELAY DEEPER MOISTURE RETURN.
AN EXAMINATION OF INSTABILITY AND MID LEVEL LAPSE RATES DOES SUPPORT
INCLUSION OF HIGHER POPS THIS PERIOD. MIXED LAYER CAPE VALUES DO
CLIMB TO 300 J/KG WHILE SURFACE BASED VALUES REACH 500 TO 1000 J/KG.
MID LEVEL LAPSE RATES DO REACH UP TO 7 DEG C/KM.
SO ALTHOUGH WE ARE CONFIDENT MEASURABLE PRECIPITATION WILL OCCUR...
THERE IS SOME UNCERTAINTY AS TO WHEN TO INCLUDE THE HIGHEST POPS.
LOOKING AT THE MOST RECENT RADAR/SATELLITE DATA...THERE IS A LARGE
AREA OF DEEP CONVECTION ONGOING ACROSS THE CENTRAL AND EASTERN GULF
COASTAL AREAS. THIS SUGGESTS DEEPEST MOISTURE RETURN MAY BE DELAYED.
EXTRAPOLATION FOR TIMING WOULD BRING THE HIGHEST RISK FOR SHOWERS
AND THUNDERSTORMS INTO THE AREA TONIGHT...MORE LIKELY LATE TONIGHT
WITH THE ARRIVAL OF AN UPPER LEVEL IMPULSE WORKING ITS WAY UP THE
CAROLINA COAST. OF COURSE THIS DOES NOT PRECLUDE SHOWERS AND SOME
THUNDERSTORMS TODAY OR THIS EVE AND HIGHER RESOLUTION MODELS ARE
SHOWING CONVECTION BREAKING OUT WITH HEATING OF THE DAY WITH PERHAPS
THE SEA BREEZE SERVING AS A FOCAL POINT. RAINFALL AMOUNTS WILL BE
HIGHLY VARIABLE...BUT SOME LOCATIONS COULD RECEIVE AS MUCH AS
THREE-QUARTERS OF AN INCH WITH ONE-QUARTER TO ONE-HALF INCH MORE
COMMON...THESE AMOUNTS JUST THROUGH TONIGHT.
THICKER CLOUD COVER WILL BE ARRIVING/DEVELOPING THROUGH THE DAY WITH
MORE OR LESS CLOUDY SKIES EXPECTED DURING THE AFTERNOON AND TONIGHT.
ALSO...AS DEWPOINTS CREEP HIGHER...WE SHOULD BEGIN TO SEE SEA
STRATUS/SEA FOG DEVELOP...PERHAPS IMPINGING ONTO THE IMMEDIATE COAST
IN SOUTHERLY FLOW LATE DAY AND ESPECIALLY TONIGHT.
HIGH TEMPS WILL BE IN THE LOWER TO MID 70S TODAY...BUT THE SEABREEZE
WILL KEEP COASTAL AREAS IN THE MID AND UPPER 60S. LOWS TONIGHT WILL
BE BALMY AS COMPARED TO RECENT NIGHTS...UPPER 50S TO AROUND 60
DEGREES.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300 AM FRIDAY...SURFACE LOW AND MID LEVEL TROUGH WILL BE WEST
OF THE AREA AT THE START OF THE PERIOD WITH THE REGION SOLIDLY IN
THE WARM SECTOR. SEVERAL FACTORS APPEAR TO BE IN PLACE SUPPORTING
CONVECTION SAT INTO SAT NIGHT. STRENGTHENING MID LEVEL SOUTHWEST
FLOW WILL CONTINUE TO PUMP MOISTURE INTO THE REGION. FORECAST
SOUNDINGS SHOW PRECIPITABLE WATER VALUES CLOSE TO 1.5 INCH. DIURNAL
INSTABILITY WILL ALSO BE PRESENT WITH HIGHS EXPECTED TO CLIMB INTO
THE LOWER 70S IN MOST AREAS. LOW LEVEL CONVERGENCE ALONG THE
RESULTANT SEA BREEZE MAY INITIATE CONVECTION IN THE AFTERNOON. ALOFT
THE APPROACHING 5H TROUGH WILL ENHANCE MID LEVEL LAPSE RATES BUT THE
UNKNOWN FACTOR AT THIS POINT REMAINS WHAT IMPACT POTENTIAL
CONVECTION IN THE NORTHEAST GULF OF MEXICO WILL HAVE ON INSTABILITY
SHOWERS/THUNDERSTORMS.
FARTHER WEST A LINE OF CONVECTION SHOULD BE DEVELOPING ASSOCIATED
WITH THE ADVANCING COLD FRONT. THIS LINE WILL MOVE INTO WHAT SHOULD
BE A MOIST/UNSTABLE ENVIRONMENT LATE SAT AND PUSH OFF THE COAST SAT
NIGHT. ALTHOUGH THE FRONT WILL HAVE PLENTY OF LOW LEVEL CONVERGENCE
AND MID LEVEL SUPPORT THERE IS SOME QUESTION AS TO THE STATE OF THE
ATMOSPHERE IT WILL BE MOVING INTO. THE CONVECTIVE LINE ASSOCIATED
WITH THE FRONT MAY END UP WEAKENING AS IT MOVES INTO THE REGION IF
EARLIER AFTERNOON CONVECTION IS MORE WIDESPREAD AND USES UP A LOT OF
THE AVAILABLE INSTABILITY. ON THE OTHER HAND SHOULD THE GULF
CONVECTION BE ABLE TO SUPPRESS MUCH OF THE ACTIVITY DURING THE FIRST
HALF OF SAT THE COLD FRONT WOULD HAVE PLENTY OF INSTABILITY TO WORK
WITH. SO IT IS NOT SO MUCH A QUESTION OF WILL IT RAIN...BUT MORE OF
A QUESTION OF WHEN WILL IT RAIN.
SEVERE WEATHER THREAT PERSISTS...ALTHOUGH WITH CAVEATS. LOW LEVEL
JETTING WILL BE WEAK FOR MUCH OF THE DAY BEFORE INCREASING TO 30 TO
35 KT JUST AHEAD OF THE FRONT. THE MAIN THREAT WOULD BE DAMAGING
WIND...ENHANCED BY STORMS MOVING CLOSE TO 30 MPH. IF STRONG/SEVERE
STORMS DEVELOP THEY ARE LIKELY TO DO SO WITH THE LINE OF CONVECTION
AHEAD OF THE FRONT...AGAIN ASSUMING DIURNAL DRIVEN CONVECTION IS
LIMITED IN SCOPE DURING THE DAY SAT.
COLD FRONT PUSHES OFF THE COAST LATE SAT NIGHT WITH THE MID LEVEL
TROUGH FOLLOWING ON SUN. COLD ADVECTION BEHIND THE FRONT WILL DROP
SUN TEMPS BELOW CLIMO...BUT COLD AIR WILL BE A LITTLE TOO LATE TO
HAVE A SIGNIFICANT IMPACT ON SAT NIGHT LOWS WHICH WILL END UP NEAR
TO SLIGHTLY ABOVE CLIMO. SUN SHOULD BE DRY WITH DEEP NORTHWEST FLOW
BEHIND THE TROUGH DROPPING PWATS UNDER .5 INCH FOR SUN AM AND UNDER
.25 INCH BY SUN EVENING. GRADIENT RELAXES SUN NIGHT BUT HIGH REMAINS
WEST OF THE AREA THROUGH THE END OF THE PERIOD SO SUN NIGHT WILL NOT
BE AN IDEAL RADIATIONAL COOLING NIGHT. STILL LOWS END UP BELOW CLIMO.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300 AM FRIDAY...LOW AMPLITUDE MID LEVEL RIDGING AND SPRAWLING
SURFACE HIGH WILL KEEP THE AREA DRY AND SEASONABLE THROUGH THE
PERIOD. COOLEST DAY WILL BE MON WITH SURFACE HIGH DIRECTLY OVERHEAD.
HIGH THEN DRIFTS OFFSHORE TUE THROUGH THU BRINGING SEVERAL DAYS OF
BEAUTIFUL SPRING WEATHER. PREVIOUSLY MEDIUM RANGE GUIDANCE HAD BEEN
MOVING A DRY COLD FRONT ACROSS THE AREA TUE NIGHT INTO WED. NOW THAT
GUIDANCE IS SUGGESTING MORE MID LEVEL AMPLIFICATION THIS SEEMS
UNLIKELY AND IN FACT THE 00Z GUIDANCE IS BACKING OFF ON THE DRY
FRONT. TEMPERATURES NEAR TO SLIGHTLY ABOVE CLIMO MON TRANSITION TO
ABOVE CLIMO MON NIGHT THROUGH THE END OF THE PERIOD.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 12Z...RETURN FLOW WILL COMMENCE SHORTLY. HAVE LEANED FAIRLY
HEAVILY ON THE HRRR EARLY...WITH SHOWERS POPPING UP ALONG THE
MYRTLES BY LATE MORNING. INCREASING SOUTHERLY GRADIENT WILL CAUSE
WINDS TO GUSTS OVER 20 KTS AT TIMES...ESPECIALLY ALONG THE COAST.
SCATTERED SHOWERS WILL GIVE WAY TO MORE WIDESPREAD RAIN THIS EVENING
AS DEEP MOISTURE MOVES INTO THE REGION. RAIN CHANCES WILL BE HIGHEST
INLAND THIS EVENING...SPREADING TO THE COAST A FEW HOURS LATER.
CEILINGS ARE A BIT PROBLEMATIC...BUT WILL GO FOR MVFR PREDOMINATELY
WITH POCKETS OF IFR POSSIBLE.
EXTENDED OUTLOOK...SHOWERS AND T-STORMS WITH MVFR/TEMPO IFR
CONDITIONS OVERNIGHT AND ON SATURDAY. VFR SUNDAY THROUGH TUESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 600 AM FRIDAY...THE PRESSURE GRADIENT BETWEEN A LARGE AREA OF
HIGH PRESSURE OFFSHORE AND A TROUGH OF LOW PRESSURE TO OUR W WILL
BE TIGHTEST TONIGHT...ESPECIALLY LATE TONIGHT AND SAT AS THE
TROUGH BEGINS TO MAKE ITS EASTWARD PUSH. THUS THIS IS WHEN THE
STRONGEST WINDS ARE EXPECTED ACROSS THE WATERS. THE STRONGEST
WINDS ARE EXPECTED ACROSS THE OUTERMOST WATERS AND EASTWARD WHERE
SEA SURFACE TEMPS ARE MUCH HIGHER THAN ACROSS THE NEAR SHORE
WATERS...THUS ALLOWING FOR THE GREATEST MIXING. WIND SPEEDS WITHIN
20 NM OF THE COAST WILL BE AS HIGH AS 15 TO 20 KT. PERSISTENTLY
HIGHER SOUTH WINDS OFFSHORE WILL ALLOW SEAS TO BUILD AND EXPECT
THE 6 FT THRESHOLD WILL BE MET ACROSS PORTIONS OF THE OUTER WATERS
AS EARLY AS THIS AFTERNOON AND MORESO TONIGHT...NECESSITATING A
SMALL CRAFT ADVISORY WHICH WILL BE RAISED AT THIS TIME.
FINALLY...HIGHER DEWPOINTS ADVECTING NORTHWARD AHEAD OF AN
APPROACHING TROUGH SHOULD ALLOW FOR THE DEVELOPMENT OF SEA
FOG...LIKELY MOST PREVALENT OVERNIGHT.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300 AM FRIDAY...SOUTHERLY FLOW WILL APPROACH 20 KT SAT AS
GRADIENT OVER THE WATERS IS PINCHED BETWEEN ADVANCING COLD FRONT AND
HIGH PRESSURE. ANTICIPATE A LINE OF CONVECTION AHEAD OF THE FRONT
WHICH WILL CROSS THE WATERS SAT EVE/NIGHT. OFFSHORE FLOW DEVELOPS
BEHIND THE FRONT WITH GRADIENT AND DEVELOPING COLD ADVECTION KEEPING
SPEEDS AROUND 20 KT. LITTLE CHANGE IN THE GRADIENT SUN AS HIGH
BUILDS KEEPS NORTHWEST WINDS A SOLID 20 KT FOR MUCH OF THE DAY.
OFFSHORE FLOW SLOWLY WEAKENS SUN NIGHT...DROPPING TO 15 KT BY THE
END OF THE PERIOD...AS GRADIENT RELAXES. SEAS 4 TO 6 FT EXPECTED SAT
INTO SUN WHEN OFFSHORE COMPONENT DROPS SEAS TO 3 TO 5 FT. CONTINUED
OFFSHORE FLOW COMBINED WITH REDUCTION IN SPEEDS SUN NIGHT WILL DROP
SEAS TO 2 TO 4 FT BY THE END OF THE PERIOD.
LONG TERM /MONDAY THROUGH TUESDAY/...
AS OF 300 AM FRIDAY...OFFSHORE FLOW AROUND 15 KT AT THE START OF THE
PERIOD WILL DECREASE DURING MON AS HIGH PRESSURE MOVES OVER HEAD.
SPEEDS WILL DROP UNDER 10 KT BY MON EVENING...BECOMING LIGHT AND
VARIABLE MON NIGHT. HIGH SHIFTS OFFSHORE FOR TUE WITH RETURN FLOW
SLOWLY RISING INTO THE 10 TO 15 KT RANGE LATE TUE AND TUE NIGHT.
SEAS WILL RUN 2 TO 3 FT FOR A MAJORITY OF THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 8 AM EDT
SATURDAY FOR AMZ250-252-254-256.
&&
$$
NEAR TERM...RJD
SHORT TERM...III
LONG TERM...III
AVIATION...SGL/RJD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
936 PM CDT SAT MAR 29 2014
.UPDATE...
ISSUED AT 936 PM CDT SAT MAR 29 2014
MADE SOME ADDITIONAL TWEAKS TO POPS/WX. MOST OF THE RETURNS IN THE
NORTHERN CWA HAVE NOT YET BEEN REACHING THE GROUND...BUT ROLLA
JUST OUTSIDE THE CWA HAS STARTED REPORTING RAIN. CONTINUED TO KEEP
SOME 20-40 POPS IN THE NORTHERN COUNTIES AND ADJUSTED THEM A BIT
SOUTH TO COUNT FOR RADAR TRENDS TO OUR WEST AS WELL AS THE HRRR
AND RAP RUNS. CONTINUE TO THINK THAT SOUTH WINDS WILL KEEP TEMPS
UP AND TYPE AS RAIN FOR NOW.
UPDATE ISSUED AT 634 PM CDT SAT MAR 29 2014
MADE A FEW MINOR TWEAKS TO POPS ALONG THE NORTHERN BORDER...BUT NO
MAJOR CHANGES FOR THIS EVENING. THE CHANCE FOR A FEW RAIN SHOWERS
IN THE NORTH WILL CONTINUE AND SOUTH WINDS WILL CONTINUE TO KEEP
TEMPS UP.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 342 PM CDT SAT MAR 29 2014
FAIRLY QUIET THIS PERIOD AND MODELS IN DECENT AGREEMENT. VERY WARM
AIRMASS WILL PROPAGATE ACROSS THE REGION TONIGHT...WITH MIN TEMPS
AROUND THE FREEZING MARK. AN UPPER WAVE SHOULD BRING SCATTERED
SHOWERS NEAR THE INTERNATIONAL BORDER TONIGHT. ON SUNDAY...COLDER
AIRMASS BEGINS TO MOVE INTO THE WESTERN FA AS THE WINTER STORM TO
THE WEST ORGANIZES AND APPROACHES THE REGION.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 342 PM CDT SAT MAR 29 2014
SUNDAY NIGHT-TUESDAY...THE LARGE WINTER STORM IS STILL ON TRACK
TO HIT THE REGION (MOSTLY ON MONDAY). THE 12Z MODELS HAVE TRENDED
SLIGHTLY SLOWER (AND NORTHWARD WITH THE HEAVIEST SNOWFALL). THE
ECMWF REMAINS THE SLOWEST/FURTHEST NORTH...WHILE THE GFS IS
FURTHEST SOUTH WITH THE HEAVIEST SNOWFALL (BUT STILL WITHIN THE
FA). THE GEM/UKMET ARE SOMEWHERE IN THE MIDDLE...AND AT THIS
POINT MAKE THE MOST SENSE. THE NAM (ALTHOUGH SIMILAR WITH QPF) IS
THE FAST OUTLIER AND HAS BEEN DISCOUNTED. THE ECMWF IS ON THE
NORTHERN EDGE OF THE ENSEMBLE ENVELOPE...AND WOULD EXPECT THIS
SOLUTION TO TREND SLIGHTLY SOUTH WITH THE HEAVIEST QPF OVER THE
NEXT FEW MODEL RUNS. AT ANY RATE...THE INGREDIENTS ARE IN PLACE
FOR HEAVY SNOW SOMEWHERE...DEPENDING ON THE EXACT TRACK OF THIS
SYSTEM. AMOUNTS WITHIN THIS HEAVY SNOW AREA COULD AMOUNT TO A FOOT
OR MORE...WITH WIDESPREAD SNOWFALL OF 6 TO 12 INCHES APPEARING
LIKELY (THE NORTHERN AND SOUTHERN EDGE OF THIS SNOWFALL AREA WILL
BE CHALLENGING). THE SLOWER TREND OF THE MODELS HAS INCREASED THE
EXPECTED NORTHERLY WINDS ON MONDAY. NO MATTER WHICH MODEL SOLUTION
(EXCEPT THE FASTER NAM) YOU LOOK AT...ANTICIPATE SPEEDS AROUND 30
KNOTS GIVEN HIGH WIND INGREDIENTS AND MOS GUIDANCE. CONFIDENCE HAS
INCREASED IN BLIZZARD CONDITIONS SOMEWHERE WITHIN THE FA...AND
WILL `UPGRADE` THE WINTER STORM WATCH TO A BLIZZARD WATCH FOR THE
`MOST LIKELY` BLIZZARD AREA. DEFINITELY NOT ENOUGH CONFIDENCE FOR
A WARNING AT THIS POINT FOR ANY AREA AS THE EXACT TRACK AND SPEED
OF THE SYSTEM WILL ULTIMATELY AFFECT P-TYPE...SNOW AMOUNTS...AND
WIND SPEEDS.
TUE NIGHT THROUGH SAT...SFC HIGH PRESSURE MOVES OVER THE FA ON
TUE NIGHT KEEPING THINGS COOL AND DRY. BY WED THE FLOW TURNS MORE
TO THE SOUTHWEST WITH MODELS DIVERGING ON SOLUTIONS. THE 12Z GFS
IS QUICKER AND BRINGS IN LIGHT SNOW ON WED WHILE THE ECMWF/GEM
KEEP WED DRY. THESE DIFFERENCES CONTINUE INTO WED NIGHT WITH THE
GFS MOVING THE LIGHT SNOW INTO THE NE FA AND THE ECMWF/GEM STILL
NOT SHOWING MUCH OF ANYTHING. MORE POTENT SYSTEM LOOKING TO BE
THU/THU NIGHT ALTHOUGH STILL NOT MUCH AGREEMENT BETWEEN THE
MODELS. THE ECMWF SHOWS THE FURTHEST NORTH SOLUTION WHICH WOULD
GIVE ANOTHER BATCH OF SNOW TO THE SOUTHERN FA. THE GFS IS THE
FURTHEST SOUTH WITH THE WAVE WHILE THE GEM IS IN BETWEEN. WILL
LEAVE LOW SNOW CHANCES ACROSS MAINLY THE SOUTHERN FA FOR NOW AND
SEE IF MODELS COME INTO BETTER AGREEMENT LATER. TEMPS GENERALLY
LOOK TO STAY ON THE COOLER SIDE THROUGHOUT BUT COULD BE GREATLY
AFFECTED BY SNOW COVER.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 634 PM CDT SAT MAR 29 2014
VFR CONDITIONS WILL CONTINUE FOR MUCH OF THE PERIOD WITH
INCREASING HIGH CLOUDS THAT WILL EVENTUALLY COME DOWN TO AROUND
5000 FT. THE STRONG SOUTH WINDS WILL DIMINISH SOMEWHAT LATER THIS
EVENING...THEN SHIFT TO THE NORTHWEST AT SOME POINT TOMORROW
MORNING. BROUGHT SOME MVFR CIGS INTO KDVL BUT THINK THE TRUE LOWER
CIGS WILL HOLD OFF FOR A BIT LONGER ACROSS MUCH OF THE FORECAST
AREA AND NOT COME IN UNTIL AFTER 00Z MONDAY.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...BLIZZARD WATCH FROM LATE SUNDAY NIGHT THROUGH LATE MONDAY NIGHT
FOR NDZ027>030-038-039-049-052-053.
WINTER STORM WATCH FROM LATE SUNDAY NIGHT THROUGH LATE MONDAY
NIGHT FOR NDZ008-016-024-026-054.
MN...BLIZZARD WATCH FROM LATE SUNDAY NIGHT THROUGH LATE MONDAY NIGHT
FOR MNZ001>003-029-030-040.
WINTER STORM WATCH FROM LATE SUNDAY NIGHT THROUGH LATE MONDAY
NIGHT FOR MNZ004>009-013>017-022>024-027-028-031-032.
&&
$$
UPDATE...JR
SHORT TERM...TG
LONG TERM...GODON/TG
AVIATION...JR
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
948 AM EDT FRI MAR 28 2014
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL PULL A COLD FRONT EAST ACROSS THE AREA
TODAY. ANOTHER LOW PRESSURE SYSTEM WILL TRACK THROUGH THE TENNESSEE
AND LOWER OHIO VALLEY ON SATURDAY. HIGH PRESSURE OVER THE UPPER
GREAT LAKES WILL EXPAND SOUTH ON SUNDAY...THEN SHIFT EAST OF THE
AREA ON MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A COLD FRONT WAS OVER NORTHWEST OHIO AND IT WILL REACH NORTHWEST
PA THIS AFTERNOON. WINDS CAN STILL BE GUSTY AHEAD OF THE FRONT BUT
BELOW WIND ADVISORY CRITERIA. SCATTERED SHOWERS WILL BE DEVELOPING
THROUGH THE MORNING AND INTO THE AFTERNOON. TEMPERATURES ARE
PEAKING NOW AND WILL SLOWLY FALL AFTER THE FRONTAL PASSAGE.
PREVIOUS DISCUSSION...
WINDS HAVE BEEN GUSTING BETWEEN 40-45 MPH (WITH EVEN A PEAK WIND
TO 50 MPH AT FINDLAY) EARLY THIS MORNING ACROSS NW AND NORTH
CENTRAL OHIO. THIS HAS BEEN OCCURRING WELL OUT AHEAD OF THE FRONT
IN THE VICINITY OF THE LOW LEVEL JET. HAVE CONTEMPLATED ISSUING A
WIND ADVISORY BUT WINDS SHOULD ONLY BE THAT STRONG FOR A COUPLE
HOUR WINDOW AT ANY GIVEN LOCATION BEFORE DECREASING WITH GUSTS
CLOSER TO 35 MPH AS WE HAVE SEEN UPSTREAM IN INDIANA AND EVEN NW
OHIO NOW. THE RUC SHOWS A DECREASING TREND FOR THE LOW LEVEL JET
AND THE HRRR HAS BEEN HIGHLIGHTING THE STRONGEST CORRIDOR OF WINDS
FROM FDY/MNN/MFD TO CLE. WINDS SHOULD START TO DECREASE FROM MFD-
CLE THROUGH 9 AM SO WILL HOLD OFF ON AN ADVISORY. NORTHEAST OHIO
WILL STILL SEE WINDS INCREASE BUT HOPEFULLY GUSTS WILL NOT BE
QUITE AS STRONG...HOLDING CLOSER TO 40 MPH FOR THE MOST PART.
WINDS WILL GUST TO AROUND 40 MPH AGAIN WITH THE FRONTAL PASSAGE
BUT THESE WILL ALSO BE BRIEF.
EARLIER DISCUSSION...
LOW PRESSURE CURRENTLY LOCATED OVER LAKE MICHIGAN WITH A COLD FRONT
EXTENDING SOUTH ACROSS ILLINOIS. WINDS HAVE BEEN INCREASING AHEAD OF
THE FRONT AND SEVERAL SITES IN INDIANA AND WESTERN OHIO HAVE BRIEFLY
GUSTED TO AROUND 40 MPH. EXPECT TO SEE THE BREEZY WINDS EXPAND
EASTWARD AND THROUGH THE EARLY MORNING HOURS WITH GUSTS IN THE 30-40
MPH RANGE...WITH LOCALLY HIGHER GUSTS TOWARDS ERIE PA WHERE
DOWNSLOPING MAY ENHANCE THE WINDS. NOT ENTIRELY OUT OF THE QUESTION
THAT WE MAY NEED A WIND ADVISORY FOR A FEW HOURS THIS MORNING IN
ERIE BUT STILL LOOKING JUST A LITTLE TOO MARGINAL TO ISSUE AT THIS
TIME AS WINDS TRY TO SHIFT TO MORE SSW WHICH IS LESS FAVORABLE.
TEMPERATURES WILL PEAK IN THE LOW 50S THIS MORNING IMMEDIATELY AHEAD
OF THE FRONT WHICH WILL REACH TOL AROUND 9 AM...CLE AROUND NOON AND
ERI EARLY THIS AFTERNOON. TEMPERATURES WILL FALL INTO THE MID AND
UPPER 40S BEHIND THE FRONT MOST AREAS THIS AFTERNOON.
ONE MORE BAND OF SHOWERS EXTENDS FROM FINDLAY SOUTHWEST AHEAD OF THE
MID-LEVEL DRY-SLOT. THIS AREA OF SHOWERS EXPECTED TO QUICKLY MOVE
NORTHEAST ACROSS OHIO THIS MORNING....WITH JUST A SLIGHT CHANCE OF
ADDITIONAL SHOWERS RE-DEVELOPING ALONG THE FRONT. THE AIR MASS DRIES
OUT QUICKLY BY THIS AFTERNOON AS A SHORTWAVE RIDGE BUILD ALOFT.
SKIES WILL START TO SCATTER OUT IN NW OHIO THIS AFTERNOON...POSSIBLY
AS FAR EAST AS CLE/CAK BY SUNSET.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
SKIES WILL CLEAR OUT THIS EVENING WITH NORTH TO NORTHEAST FLOW ON
THE SOUTHERN PERIPHERY OF HIGH PRESSURE BUILD OVER THE UPPER GREAT
LAKES. LOWS WILL FALL INTO THE LOW 30S TONIGHT.
THE FORECAST REMAINS A CHALLENGE FOR SATURDAY AS MODELS CONTINUE TO
SHOW SPREAD WITH THERMAL PROFILES WHICH WILL HAVE AN EFFECT ON
PRECIPITATION TYPE. SHORTWAVE ENERGY OBSERVED OVER THE ROCKY
MOUNTAINS THIS MORNING WILL DEEPEN INTO A FAIRLY SHARP TROUGH AS
IT CROSSES THE MISSISSIPPI VALLEY ON SATURDAY. A SURFACE LOW WILL
DEEPEN AHEAD OF THIS FEATURE...TRACKING NORTHEAST FROM THE
TENNESSEE TO LOWER OHIO VALLEY. FRONTOGENESIS WILL STRENGTHEN OVER
THE AREA IN THE 850-700MB LAYER LEADING TO WIDESPREAD
PRECIPITATION. THERE WILL BE A DRY NORTHERLY FLOW IN THE LOW
LEVELS TO START THE DAY WHICH MAY SLIGHTLY DELAY PRECIPITATION.
MODELS VARY WITH HOW MUCH WARM AIR WILL BE IN PLACE ALOFT TO START
THE DAY WITH THE ECMWF ADVERTISING A WARM LAYER OF 1-3C NEAR 850MB
WHILE THE GFS ALSO STARTS THE DAY OFF WARM IN THE EASTERN
CWA...BUT QUICKLY COOLS THE COLUMN FROM WEST TO EAST. SUSPECT WE
WILL SEE WESTERN AREAS MAKE A QUICK TRANSITION TO A WET SNOW ON
SATURDAY MORNING WHILE RAIN IS MORE PREVALENT EAST OF ABOUT I-71.
GOOD PRECIPITATION RATES ARE EXPECTED AS A NUMBER OF FACTORS COME
TOGETHER...INCLUDING FAVORABLE JET DYNAMICS ALOFT.
THE SNOWFALL FORECAST IS COMPLICATED GIVEN IT BEING A DAYTIME SNOW
EVENT AT THE END OF MARCH. SNOW WILL ACCUMULATE BETTER ON GRASSY
SURFACES THAN ROADWAYS...ESPECIALLY AS TEMPERATURES HOVER IN THE
LOW TO MID 30S. THE SNOW WILL BE WET WHICH WILL LEAD TO MORE
COMPACTION. HAVE GONE WITH A BLEND OF THE COOLER GFS/NAM AND
WARMER ECMWF/GEM WITH REGARD TO PRECIP TYPE BUT LEANING TOWARDS
THE LOWER ACCUMULATIONS GIVEN THE LIMITATIONS MENTIONED ABOVE.
GOING WITH A PURE 00Z/GFS SOLUTION COULD YIELD AS MUCH AS 3-5
INCHES FOR A CORRIDOR FROM CLE/ERI AS SNOW STARTS TO ACCUMULATE
MORE EFFICIENTLY AS WE HEAD TOWARDS SUNSET. THE GOING FORECAST
ONLY CALLS FOR A COUPLE INCHES BUT MAY NEED TO BE RAMPED UP BASED
ON LATER MODEL GUIDANCE. DID ADJUST HIGH TEMPERATURES DOWN A FEW
DEGREES ON SATURDAY WITH LITTLE DIURNAL RISE.
PRECIPITATION WILL COME TO AN END ON SATURDAY NIGHT WITH LITTLE
INFLUENCE FROM LAKE ERIE GIVEN 850MB TEMPERATURES ONLY DROPPING TO
AROUND -4C. HIGH PRESSURE THEN BUILDS OVER THE AREA ON SUNDAY WITH
MOSTLY SUNNY SKIES. SOUTHERLY FLOW RETURNS ON MONDAY AHEAD OF THE
NEXT SYSTEM WITH HIGHS IN THE UPPER 50S TO LOW 60S.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
THE MODELS CONTINUE TO BE SIMILAR IN THEIR FORECASTS WITH SOME MINOR
DETAILS TO BE WORKED OUT. A COLD FRONT WILL CROSS THE AREA ON
TUESDAY. THE ECMWF HAS BECOME SLOWER THAN THE OTHER MODELS AND
CONSEQUENTLY IS WARMER (60S VERSUS 50S FOR HIGHS). WOULD RATHER
REMAIN CONSERVATIVE AND NEAR THE CURRENT FORECAST UNTIL WE SEE A
MORE DEFINITE TREND.
THE NEXT PANHANDLE HOOK IS PROGGED TO COME OUT OF THE SOUTHERN
PLAINS BY WEDNESDAY NIGHT AND MOVE TO THE GREAT LAKES ON THURSDAY.
INCREASED THE CHANCE OF RAIN IN THE FORECAST FOR WEDNESDAY NIGHT AND
THURSDAY. WE MAY TAKE A WHILE TO BREAK INTO THE WARM SECTOR WITH AN
EAST FLOW PROGGED FOR A WHILE WEDNESDAY INTO THURSDAY SO DID NOT GO
AS WARM AS IT COULD BE FOR HIGH TEMPS AND DID NOT MENTION THUNDER...
THERE IS PLENTY OF TIME TO TREND THE FORECAST IN THAT DIRECTION IF
NECESSARY.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
WILL ALLOW FOR SHOWERS AT THE EASTERN TAF SITES KCAK KYNG KERI
EARLY THIS MORNING. CANNOT RULE OUT A BRIEF SHOWER/SPRINKLE WHEN
THE ACTUAL FRONT MOVES THROUGH MID MORNING THROUGH EARLY AFTERNOON
BUT DID NOT INCLUDE IT IN THE FORECAST. CEILINGS WILL LOWER TO
MVFR AFTER FRONTAL PASSAGE. GUSTY SOUTH WINDS WILL BECOME
SOUTHWEST AND EVENTUALLY WEST...THEN DIMINISH QUICKLY LATE THIS
AFTERNOON/EARLY EVENING. GUSTS 35 TO NEAR 40 KNOTS THIS MORNING.
CLEARING AND VFR CONDITIONS WILL SPREAD FROM WEST TO EAST LATE
THIS AFTERNOON AND THIS EVENING. MID AND HIGH CLOUDS WILL INCREASE
SATURDAY MORNING.
.OUTLOOK...NON VFR WILL REDEVELOP SAT AND PERSIST ACROSS NE OH/NW
PA INTO SUNDAY. NON VFR POSSIBLE AGAIN TUE.
&&
.MARINE...
THE STRONG LOW LEVEL JET WILL BE OVER LAKE ERIE THIS MORNING BUT
WITH THE LAKE STILL SO COLD IT IS UNLIKELY THE WIND WILL MIX
DOWN TO THE SURFACE. SOUTH WINDS OF 20-30 KNOTS SHOULD DO IT THIS
MORNING. THERE COULD BE BETTER MIXING AS THE FRONT CROSSES THE LAKE
FROM MID MORNING THROUGH MID AFTERNOON AND AN OBSERVATION OR TWO
NEAR 35 KNOTS IS POSSIBLE BUT DO NOT WANT TO ISSUE A GALE WARNING
FOR AN ISOLATED/BRIEF EVENT.
HIGH PRESSURE WILL BUILD IN QUICKLY TONIGHT. THE NEXT LOW PRESSURE
SYSTEM WILL PASS SOUTH OF THE LAKE ON SATURDAY AND WINDS WILL VEER
TO THE NORTH AND NORTHEAST. NNE WINDS COULD BECOME BRISK ON
SATURDAY...THERE IS STILL SOME UNCERTAINTY ON THE TRACK AND
STRENGTH OF THE LOW. HIGH PRESSURE IS EXPECTED TO SPREAD ACROSS THE
EASTERN GREAT LAKES SUNDAY INTO MONDAY. THE NEXT LOW WILL TRACK
ACROSS THE WESTERN GREAT LAKES BY MONDAY NIGHT WITH WINDS ON LAKE
ERIE INCREASING WITH THE NEXT COLD FRONT ON TUESDAY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KEC
NEAR TERM...KEC/KIELTYKA
SHORT TERM...KEC
LONG TERM...KOSARIK
AVIATION...KOSARIK
MARINE...KOSARIK
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
737 AM EDT FRI MAR 28 2014
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL PULL A COLD FRONT EAST ACROSS THE AREA
TODAY. ANOTHER LOW PRESSURE SYSTEM WILL TRACK THROUGH THE TENNESSEE
AND LOWER OHIO VALLEY ON SATURDAY. HIGH PRESSURE OVER THE UPPER
GREAT LAKES WILL EXPAND SOUTH ON SUNDAY...THEN SHIFT EAST OF THE
AREA ON MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WINDS HAVE BEEN GUSTING BETWEEN 40-45 MPH (WITH EVEN A PEAK WIND TO
50 MPH AT FINDLAY) EARLY THIS MORNING ACROSS NW AND NORTH CENTRAL
OHIO. THIS HAS BEEN OCCURRING WELL OUT AHEAD OF THE FRONT IN THE
VICINITY OF THE LOW LEVEL JET. HAVE CONTEMPLATED ISSUING A WIND
ADVISORY BUT WINDS SHOULD ONLY BE THAT STRONG FOR A COUPLE HOUR
WINDOW AT ANY GIVEN LOCATION BEFORE DECREASING WITH GUSTS CLOSER TO
35 MPH AS WE HAVE SEEN UPSTREAM IN INDIANA AND EVEN NW OHIO NOW. THE
RUC SHOWS A DECREASING TREND FOR THE LOW LEVEL JET AND THE HRRR HAS
BEEN HIGHLIGHTING THE STRONGEST CORRIDOR OF WINDS FROM FDY/MNN/MFD
TO CLE. WINDS SHOULD START TO DECREASE FROM MFD-CLE THROUGH 9 AM SO
WILL HOLD OFF ON AN ADVISORY. NORTHEAST OHIO WILL STILL SEE WINDS
INCREASE BUT HOPEFULLY GUSTS WILL NOT BE QUITE AS STRONG...HOLDING
CLOSER TO 40 MPH FOR THE MOST PART. WINDS WILL GUST TO AROUND 40
MPH AGAIN WITH THE FRONTAL PASSAGE BUT THESE WILL ALSO BE BRIEF.
EARLIER DISCUSSION...
LOW PRESSURE CURRENTLY LOCATED OVER LAKE MICHIGAN WITH A COLD FRONT
EXTENDING SOUTH ACROSS ILLINOIS. WINDS HAVE BEEN INCREASING AHEAD OF
THE FRONT AND SEVERAL SITES IN INDIANA AND WESTERN OHIO HAVE BRIEFLY
GUSTED TO AROUND 40 MPH. EXPECT TO SEE THE BREEZY WINDS EXPAND
EASTWARD AND THROUGH THE EARLY MORNING HOURS WITH GUSTS IN THE 30-40
MPH RANGE...WITH LOCALLY HIGHER GUSTS TOWARDS ERIE PA WHERE
DOWNSLOPING MAY ENHANCE THE WINDS. NOT ENTIRELY OUT OF THE QUESTION
THAT WE MAY NEED A WIND ADVISORY FOR A FEW HOURS THIS MORNING IN
ERIE BUT STILL LOOKING JUST A LITTLE TOO MARGINAL TO ISSUE AT THIS
TIME AS WINDS TRY TO SHIFT TO MORE SSW WHICH IS LESS FAVORABLE.
TEMPERATURES WILL PEAK IN THE LOW 50S THIS MORNING IMMEDIATELY AHEAD
OF THE FRONT WHICH WILL REACH TOL AROUND 9 AM...CLE AROUND NOON AND
ERI EARLY THIS AFTERNOON. TEMPERATURES WILL FALL INTO THE MID AND
UPPER 40S BEHIND THE FRONT MOST AREAS THIS AFTERNOON.
ONE MORE BAND OF SHOWERS EXTENDS FROM FINDLAY SOUTHWEST AHEAD OF THE
MID-LEVEL DRY-SLOT. THIS AREA OF SHOWERS EXPECTED TO QUICKLY MOVE
NORTHEAST ACROSS OHIO THIS MORNING....WITH JUST A SLIGHT CHANCE OF
ADDITIONAL SHOWERS RE-DEVELOPING ALONG THE FRONT. THE AIR MASS DRIES
OUT QUICKLY BY THIS AFTERNOON AS A SHORTWAVE RIDGE BUILD ALOFT.
SKIES WILL START TO SCATTER OUT IN NW OHIO THIS AFTERNOON...POSSIBLY
AS FAR EAST AS CLE/CAK BY SUNSET.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
SKIES WILL CLEAR OUT THIS EVENING WITH NORTH TO NORTHEAST FLOW ON
THE SOUTHERN PERIPHERY OF HIGH PRESSURE BUILD OVER THE UPPER GREAT
LAKES. LOWS WILL FALL INTO THE LOW 30S TONIGHT.
THE FORECAST REMAINS A CHALLENGE FOR SATURDAY AS MODELS CONTINUE TO
SHOW SPREAD WITH THERMAL PROFILES WHICH WILL HAVE AN EFFECT ON
PRECIPITATION TYPE. SHORTWAVE ENERGY OBSERVED OVER THE ROCKY
MOUNTAINS THIS MORNING WILL DEEPEN INTO A FAIRLY SHARP TROUGH AS
IT CROSSES THE MISSISSIPPI VALLEY ON SATURDAY. A SURFACE LOW WILL
DEEPEN AHEAD OF THIS FEATURE...TRACKING NORTHEAST FROM THE
TENNESSEE TO LOWER OHIO VALLEY. FRONTOGENESIS WILL STRENGTHEN OVER
THE AREA IN THE 850-700MB LAYER LEADING TO WIDESPREAD
PRECIPITATION. THERE WILL BE A DRY NORTHERLY FLOW IN THE LOW
LEVELS TO START THE DAY WHICH MAY SLIGHTLY DELAY PRECIPITATION.
MODELS VARY WITH HOW MUCH WARM AIR WILL BE IN PLACE ALOFT TO START
THE DAY WITH THE ECMWF ADVERTISING A WARM LAYER OF 1-3C NEAR 850MB
WHILE THE GFS ALSO STARTS THE DAY OFF WARM IN THE EASTERN
CWA...BUT QUICKLY COOLS THE COLUMN FROM WEST TO EAST. SUSPECT WE
WILL SEE WESTERN AREAS MAKE A QUICK TRANSITION TO A WET SNOW ON
SATURDAY MORNING WHILE RAIN IS MORE PREVALENT EAST OF ABOUT I-71.
GOOD PRECIPITATION RATES ARE EXPECTED AS A NUMBER OF FACTORS COME
TOGETHER...INCLUDING FAVORABLE JET DYNAMICS ALOFT.
THE SNOWFALL FORECAST IS COMPLICATED GIVEN IT BEING A DAYTIME SNOW
EVENT AT THE END OF MARCH. SNOW WILL ACCUMULATE BETTER ON GRASSY
SURFACES THAN ROADWAYS...ESPECIALLY AS TEMPERATURES HOVER IN THE
LOW TO MID 30S. THE SNOW WILL BE WET WHICH WILL LEAD TO MORE
COMPACTION. HAVE GONE WITH A BLEND OF THE COOLER GFS/NAM AND
WARMER ECMWF/GEM WITH REGARD TO PRECIP TYPE BUT LEANING TOWARDS
THE LOWER ACCUMULATIONS GIVEN THE LIMITATIONS MENTIONED ABOVE.
GOING WITH A PURE 00Z/GFS SOLUTION COULD YIELD AS MUCH AS 3-5
INCHES FOR A CORRIDOR FROM CLE/ERI AS SNOW STARTS TO ACCUMULATE
MORE EFFICIENTLY AS WE HEAD TOWARDS SUNSET. THE GOING FORECAST
ONLY CALLS FOR A COUPLE INCHES BUT MAY NEED TO BE RAMPED UP BASED
ON LATER MODEL GUIDANCE. DID ADJUST HIGH TEMPERATURES DOWN A FEW
DEGREES ON SATURDAY WITH LITTLE DIURNAL RISE.
PRECIPITATION WILL COME TO AN END ON SATURDAY NIGHT WITH LITTLE
INFLUENCE FROM LAKE ERIE GIVEN 850MB TEMPERATURES ONLY DROPPING TO
AROUND -4C. HIGH PRESSURE THEN BUILDS OVER THE AREA ON SUNDAY WITH
MOSTLY SUNNY SKIES. SOUTHERLY FLOW RETURNS ON MONDAY AHEAD OF THE
NEXT SYSTEM WITH HIGHS IN THE UPPER 50S TO LOW 60S.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
THE MODELS CONTINUE TO BE SIMILAR IN THEIR FORECASTS WITH SOME MINOR
DETAILS TO BE WORKED OUT. A COLD FRONT WILL CROSS THE AREA ON
TUESDAY. THE ECMWF HAS BECOME SLOWER THAN THE OTHER MODELS AND
CONSEQUENTLY IS WARMER (60S VERSUS 50S FOR HIGHS). WOULD RATHER
REMAIN CONSERVATIVE AND NEAR THE CURRENT FORECAST UNTIL WE SEE A
MORE DEFINITE TREND.
THE NEXT PANHANDLE HOOK IS PROGGED TO COME OUT OF THE SOUTHERN
PLAINS BY WEDNESDAY NIGHT AND MOVE TO THE GREAT LAKES ON THURSDAY.
INCREASED THE CHANCE OF RAIN IN THE FORECAST FOR WEDNESDAY NIGHT AND
THURSDAY. WE MAY TAKE A WHILE TO BREAK INTO THE WARM SECTOR WITH AN
EAST FLOW PROGGED FOR A WHILE WEDNESDAY INTO THURSDAY SO DID NOT GO
AS WARM AS IT COULD BE FOR HIGH TEMPS AND DID NOT MENTION THUNDER...
THERE IS PLENTY OF TIME TO TREND THE FORECAST IN THAT DIRECTION IF
NECESSARY.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
WILL ALLOW FOR SHOWERS AT THE EASTERN TAF SITES KCAK KYNG KERI
EARLY THIS MORNING. CANNOT RULE OUT A BRIEF SHOWER/SPRINKLE WHEN
THE ACTUAL FRONT MOVES THROUGH MID MORNING THROUGH EARLY AFTERNOON
BUT DID NOT INCLUDE IT IN THE FORECAST. CEILINGS WILL LOWER TO
MVFR AFTER FRONTAL PASSAGE. GUSTY SOUTH WINDS WILL BECOME
SOUTHWEST AND EVENTUALLY WEST...THEN DIMINISH QUICKLY LATE THIS
AFTERNOON/EARLY EVENING. GUSTS 35 TO NEAR 40 KNOTS THIS MORNING.
CLEARING AND VFR CONDITIONS WILL SPREAD FROM WEST TO EAST LATE
THIS AFTERNOON AND THIS EVENING. MID AND HIGH CLOUDS WILL INCREASE
SATURDAY MORNING.
.OUTLOOK...NON VFR WILL REDEVELOP SAT AND PERSIST ACROSS NE OH/NW
PA INTO SUNDAY. NON VFR POSSIBLE AGAIN TUE.
&&
.MARINE...
THE STRONG LOW LEVEL JET WILL BE OVER LAKE ERIE THIS MORNING BUT
WITH THE LAKE STILL SO COLD IT IS UNLIKELY THE WIND WILL MIX
DOWN TO THE SURFACE. SOUTH WINDS OF 20-30 KNOTS SHOULD DO IT THIS
MORNING. THERE COULD BE BETTER MIXING AS THE FRONT CROSSES THE LAKE
FROM MID MORNING THROUGH MID AFTERNOON AND AN OBSERVATION OR TWO
NEAR 35 KNOTS IS POSSIBLE BUT DO NOT WANT TO ISSUE A GALE WARNING
FOR AN ISOLATED/BRIEF EVENT.
HIGH PRESSURE WILL BUILD IN QUICKLY TONIGHT. THE NEXT LOW PRESSURE
SYSTEM WILL PASS SOUTH OF THE LAKE ON SATURDAY AND WINDS WILL VEER
TO THE NORTH AND NORTHEAST. NNE WINDS COULD BECOME BRISK ON
SATURDAY...THERE IS STILL SOME UNCERTAINTY ON THE TRACK AND
STRENGTH OF THE LOW. HIGH PRESSURE IS EXPECTED TO SPREAD ACROSS THE
EASTERN GREAT LAKES SUNDAY INTO MONDAY. THE NEXT LOW WILL TRACK
ACROSS THE WESTERN GREAT LAKES BY MONDAY NIGHT WITH WINDS ON LAKE
ERIE INCREASING WITH THE NEXT COLD FRONT ON TUESDAY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KEC
NEAR TERM...KEC
SHORT TERM...KEC
LONG TERM...KOSARIK
AVIATION...KOSARIK
MARINE...KOSARIK
AREA FORECAST DISCUSSION
NWS PORTLAND OR
916 PM PDT THU MAR 27 2014
.SYNOPSIS...RAIN WILL INCREASE TONIGHT AS A WARM FRONT APPROACHES
FROM THE SOUTHWEST. WILL HAVE RAIN...HEAVY AT TIMES LATER TONIGHT AND
FRIDAY. COOLER CONDITIONS WITH SHOWERS EXPECTED FRI NIGHT
THROUGH SUN...WITH SNOW AT THE CASCADE PASSES. UNSETTLED WEATHER
CONTINUES INTO NEXT WEEK.
&&
.UPDATE...MADE MINOR CHANGES WITH THE EVENING UPDATE. HAVE ADDED A
SLIGHT CHANCE FOR THUNDERSTORMS TO SW WASHINGTON AND THE NORTHER
OREGON COAST RANGE FRIDAY AFTERNOON AND ACROSS THE ENTIRE PORTLAND
FORECAST AREA SATURDAY AFTERNOON. ALSO INCREASED QPF ALONG THE COAST
AND COAST RANGE A TAD FOR SATURDAY. OTHERWISE...PREVIOUS FORECAST IS
ON TRACK WITH A COMPLEX LOW BRINGING ROUNDS OF RAIN AND MOUNTAIN SNOW
THROUGH EARLY NEXT WEEK. THE FIRST SYSTEM OF INTEREST IS A WARM FRONT
THAT WILL PRODUCE STEADY RAIN AND HIGH ELEVATION (ABOVE 5500 FEET)
SNOW TONIGHT AND FRIDAY. THIS WILL BE CLOSELY FOLLOWED BY A COLD FRONT
FRIDAY NIGHT AND SATURDAY. SNOW LEVELS WILL LOWER SATURDAY AFTERNOON
WITH SNOW ACCUMULATIONS LIKELY FOR THE CASCADE PASSES. THERE IS A
GOOD CHANCE THAT SMALL HAIL WILL ACCOMPANY MANY OF THE SHOWERS
SATURDAY AFTERNOON.HARTLEY
PREVIOUS SHORT TERM DISCUSSION...TODAY THROUGH SATURDAY...
SHOWERS CONTINUE IN THE COOLER ONSHORE FLOW THIS AFTERNOON. THESE MAY
STILL PACK SOME PUNCH...WITH A BRIEF DOWNPOUR. BUT SHOULD NOT BE AS
INTENSE AS THOSE OVER THE PAST FEW DAYS. SHOWERS WILL DECREASE THIS
EVENING AS THE UPPER LOW SHIFTS FURTHER INLAND OVER WASHINGTON.
OCCASIONAL SNOW IN THE CASCADES AS THE PASSES...BUT NOT MUCH MORE
WILL FALL...WITH A FEW MORE INCHES INTO THIS EVENING.
WARM FRONT WILL PUSH INTO THE REGION FROM THE SW TONIGHT. DECENT
ISENTROPIC LIFT STARTS LATER THIS EVENING. LOOKS GOOD THAT RAIN WILL
DEVELOP ALONG THE CENTRAL OREGON COAST THIS EVENING...AND SPREAD N
AND E OVERNIGHT. RAIN WILL BECOME HEAVY AT TIMES LATER TONIGHT AND
CONTINUE ON FRI. STILL LOOKS LIKE GOOD 2 TO 5 INCHES OF RAIN...WITH
HEAVIEST RAINFALL OVER THE OREGON MTNS. IN THE CASCADES...LIKELY 1
TO 3 INCHES OF RAIN. HOWEVER...WILL SEE THIS START AS SNOW WITH 2 TO
5 INCHES ACCUMULATING OVERNIGHT BEFORE TURNING TO RAIN LATE
TONIGHT/EARLY FRI AS SNOW LEVELS CLIMB TO NEAR 6000 FT. BUT ABOVE
6000 FT...COULD GET UP TO 1 FOOT OF SNOW LATER TONIGHT AND FRI.
NOT FLOODING EXPECTED AT THIS TIME...BUT RIVERS WILL SEE SHARP RISES
FRI DUE TO THE RAIN. MODELS MOSTLY AGREE THAT AXIS OF HEAVIEST RAIN
SHIFTS INTO SW OREGON/NW CALIF ON LATER FRI AFTERNOON AND EVENING.
RAIN WILL TRANSITION TO SHOWERS FRI EVENING AS THE FRONT DROPS SLOWLY
SOUTHWARD INTO SW OREGON. OTHER CONCERN WILL BE SOMEWHAT ELEVATED
POTENTIAL FOR MUD/LANDSLIDES DUE TO SATURATED SOILS...PRIMARILY ALONG
THE COAST...THROUGH COAST RANGES AND IN COLUMBIA GORGE ON FRI AND
INTO FRI NIGHT.
EVEN THROUGH PRES GRADIENTS INCREASE TONIGHT AND FRI AM...STILL WILL
NOT BE ENOUGH TO CREATE ANY WIDESPREAD PROBLEMS. THIS SAID IT SEEMS
REASONABLE TO EXPECT GUSTS 40 TO 45 MPH ON THE COAST AND 25 TO 35 MPH
FROM THE COAST RANGE INLAND.
THE UPPER TROUGH WILL REMAIN IN PLACE THROUGH SATURDAY BRINGING
PERIODIC SHOWER BANDS WITH SNOW LEVELS LOWERING TO 4000 FEET
ONCE AGAIN. MAY NEED TO CONSIDER ANOTHER ROUND OF MARGINAL CASCADE
SNOW ADVISORIES DEPENDING ON THE QPF DETAILS THAT EMERGE. SATURDAY
WILL BE A COOL SPRING DAY...WITH PLENTY OF SHOWERS AND EVEN ISOLATED
THUNDERSTORMS WITH SMALL HAIL. WITH SNOW LEVELS STILL DOWN...WILL
CONTINUE TO SEE SNOW IN THE CASCADES. ROCKEY.
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
SATURDAY NIGHT THROUGH WEDNESDAY... EXPECT MORE OF THE SAME COOL AND
WET WEATHER FOR THE EXTENDED FCST PERIOD. A BROAD UPPER LEVEL TROUGH
WILL REMAIN OVER THE NE PAC OVER THE WEEKEND AND INTO EARLY NEXT
WEEK. NO SIGNIFICANT IMPACTS ARE EXPECTED DURING THIS TIME...BUT
PERIODIC WAVES ROTATING THROUGH THE TROUGH WILL BRING TIMES OF
ENHANCED SHOWER ACTIVITY. MUCH OF THE PRECIPITATION SHOULD FALL AS
SNOW AT THE CASCADE PASSES...BUT ACCUMULATIONS SHOULD BE RELATIVELY
LIGHT. OTHERWISE...EXPECT PLENTY OF CLOUDS AND TEMPS A FEW DEGREES
BELOW NORMAL. CONFIDENCE IS INCREASING THAT A MORE ORGANIZED FRONTAL
SYSTEM WILL MOVE INTO THE PAC NW TOWARDS THE MIDDLE OF NEXT
WEEK. PYLE
&&
.AVIATION...EXPECT MAINLY VFR CONDITIONS THIS EVENING TO
TRANSITION TO A MIX OF IFR AND MVFR CONDITIONS. THESE LOWER FLIGHT
CONDITIONS SHOULD PERSIST FOR MUCH OF FRIDAY...WITH NORTHERN TAF
SITES TRENDING VFR EARLIER IN THE AFTERNOON THAN SOUTHERN TAF
SITES.
KPDX AND APPROACHES...STEADIER RAIN WILL BEGIN TO SPREAD IN AFTER
09Z AND CONTINUE FOR MUCH OF FRIDAY. EXPECT A LOT OF MVFR
CONDITIONS LATE TONIGHT AND FRIDAY WITH HIGH END IFR CONDITIONS
POSSIBLE FOR BRIEF PERIODS. EAST WINDS SHOULD KEEP CONDITIONS MORE
ON THE MVFR SIDE THOUGH. /NEUMAN
&&
.MARINE...WINDS HAVE BEEN SLOWER TO INCREASE THAN MODELS HAVE
PREDICTED THUS FAR. NONETHELESS...BUOY 50 IS STARTING TO PICK UP AND
SHOULD INCREASE INTO LOW END GALE FORCE LEVELS AFTER MIDNIGHT. THE
LATEST RAP MODEL WINDS SHOULD LOW END GALE FORCE WINDS SURGING UP
THE INNER WATERS TO THE COLUMBIA RIVER MOUTH. HOWEVER...THE
NAM...LOCAL WRF MODEL AND HRRR ALL SEEM TO SUGGEST THE HIGHER GUSTS
WILL REMAIN OVER THE CENTRAL OREGON WATERS. AS A RESULT...KEPT THE
INHERITED SMALL CRAFT ADVISORIES IN PLACE FOR THE NORTHERN WATERS
AND THE GALE WARNING FOR THE CENTRAL OREGON WATERS...BUT AM A BIT
WORRIED WE COULD SEE A BRIEF PERIOD OF LOW END GALE FORCE WINDS UP
NORTH. IN ADDITION...A COASTAL JET WILL LIKELY ENHANCE WINDS WITHIN
20 NM OF THE COAST.
SEAS SHOULD BUMP UP A COUPLE FEET FROM THEIR CURRENT LEVELS
FRIDAY...ESPECIALLY OVER THE CENTRAL OREGON WATERS. THIS WILL BE
LARGELY IN RESPONSE TO THE GUSTY WINDS TONIGHT AND FRIDAY MORNING.
/NEUMAN
ANOTHER SYSTEM WILL BRING ANOTHER SURGE OF WINDS ON SAT...WITH
ANOTHER LOW END GALE LOOKING LIKE A POSSIBILITY AT THIS POINT.
STRONGER WESTERLY SWELL IS MODELED TO BUILD LATE SAT AND SUN. THE
LATEST ENP GUIDANCE INDICATES THAT SEAS MAY BUILD INTO THE MID
TEENS. YET ANOTHER FRONT ARRIVES LATE SUN INTO MON. PYLE
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 5 PM PDT FRIDAY FOR
COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR OUT
60 NM.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 AM PDT FRIDAY
FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR
OUT 60 NM.
GALE WARNING UNTIL 1 PM PDT FRIDAY FOR COASTAL WATERS FROM
CASCADE HEAD OR TO FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 2 AM TO
6 AM PDT FRIDAY.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 2 PM TO
6 PM PDT FRIDAY.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA..
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
521 PM CDT FRI MAR 28 2014
.UPDATE...
QUICK UPDATE TO ADD MENTION OF SEVERE THUNDERSTORM WATCH 39 WHICH
WILL INCLUDE THE HOUSTON METRO AREA THIS EVENING. 38
&&
.PREV DISCUSSION... /ISSUED 328 PM CDT FRI MAR 28 2014/
DISCUSSION...
AT 2 PM...A WEAK SURFACE LOW WAS LOCATED OVER CENTRAL TEXAS WITH A
WARM FRONT TO THE NORTHEAST...A DRY LINE EXTENDING SOUTH TOWARD
LAREDO AND A COLD FRONT EXTENDING WEST TOWARD THE BIG BEND.
CONVECTION HAS FIRED IN CENTRAL TEXAS THIS AFTERNOON BUT COVERAGE
REMAINS LIMITED. A SOUNDING FROM TEXAS A&M SHOWS A DECENT CAP
BETWEEN 900-800 MB AND CONSIDERABLE DRY AIR AT 800 MB. LOOKS LIKE
TEMPS WILL NEED TO WARM TO AROUND 86 DEGREES TO BREAK THE CAP.
CONVECTION OVER CENTRAL TEXAS WILL CONTINUE TO PUSH EAST AND COULD
HOLD TOGETHER AND MOVE ACROSS THE NORTHERN THIRD OF SE TX. THE
RAP...TEXAS TECH WRF AND HRRR ALL ARE SUPPORTIVE OF CONVECTION
MOVING ACROSS THE NORTH PART OF SE TX THIS EVENING BUT ALL THREE
MODELS HAVE BEEN TOO AGGRESSIVE WITH RAIN CHANCES YESTERDAY AND
AGAIN TODAY. WILL GO WITH LIKELY POPS OVER THE NORTH AND CHANCE
POPS CENTRAL. WILL MENTION SOME STORMS SEVERE OVER THE NORTH.
DENSE SEA FOG CONTINUES ALONG THE COAST. WEB CAMS AND SFC OBS CONT
TO SHOW DENSE SEA FOG IMPINGING ON THE COAST AND OFFSHORE. WILL
PROBABLY NEED A DENSE FOG ADVISORY TONIGHT FOR THE COASTAL
COUNTIES THROUGH 06Z. THE RAP AND GFS ARE FASTER WITH A COLD FRONT
TONIGHT AND IT APPEARS THAT THE FRONT WILL CLEAR THE COAST CLOSER
TO 06Z THAN 12Z SAT. ONCE WINDS GO OFFSHORE...DRIER AIR WILL
FILTER IN AND THE FOG WILL BEGIN TO DISSIPATE. HIGH PRESSURE WILL
DOMINATE SATURDAY AND SUNDAY WITH SEASONAL TEMPS AND PLENTY OF
SUNSHINE.
CLOUDS WILL RETURN LATE SUNDAY NIGHT AND PERSIST THROUGH MUCH OF
THE WEEK AHEAD AS HIGH PRESSURE DRIFTS EAST AND ONSHORE WINDS
PREVAIL. FCST SOUNDINGS SHOW SATURATION BENEATH A CAP SO FEEL
SOME STREAMER SHOWERS WILL BE POSSIBLE STARTING TUESDAY AND
CONTINUING THROUGH FRIDAY. TEMPERATURES WILL ALSO BE MILDER NEXT
WEEK WITH HIGHS NEAR 80 AND LOWS IN THE MID 60S. SOME DIFFERENCES
WITH REGARD TO TIMING OF DISTURBANCES EMBEDDED IN THE UPPER FLOW
SO WILL KEEP RAIN CHANCES ON THE LOW SIDE FOR NOW. GFS/ECMWF WITH
THE TIMING OF THE NEXT COLD FRONT EITHER NEXT FRIDAY OR SATURDAY.
43
MARINE...
DENSE SEA FOG TO BE THE MAIN ISSUE TONIGHT AS THE NEARSHORE DENSE
DECK CREEPS BACK ONTO THE COAST IN THE COMING HOURS. ANOTHER DENSE
SEA FOG ADVISORY LIKELY IN THE HOURS LEADING UP TO THE COLD FRONT
THAT IS TIMED TO REACH THE SHORELINE AROUND MIDNIGHT...OR SHORTLY
THEREAFTER. THIS FRONTAL PASSAGE WILL SCOUR OUT THE LOWER LEVEL
MOISTURE AND RESIDENT FOG AND CLEAR SKIES THROUGH EARLY SATURDAY
MORNING. LIGHT RAIN OR DRIZZLE WILL ACCOMPANY THIS FOG. POST-FRONTAL
NORTHERLIES OVER THE FAR OFFSHORE WATERS WILL LIKELY INCREASE TO
SCEC CRITERIA FOR A SHORT WHILE SATURDAY MORNING...GENERALLY 15
KNOTS OR LESS OVER THE BAYS AND NEARSHORE WATERS WITH OCCASIONAL 15-
20KT GUSTS OVER A SLIGHT CHOP. AS HIGH PRESSURE MOVES ACROSS FROM
WEST-TO-EAST...LIGHT EASTERLIES WILL SLOWLY VEER SOUTHEASTERLY BY
SUNDAY NIGHT. 31
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 52 78 49 76 53 / 60 10 10 10 0
HOUSTON (IAH) 58 79 52 77 55 / 40 10 10 10 0
GALVESTON (GLS) 64 74 59 73 60 / 20 10 10 10 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...DENSE FOG ADVISORY UNTIL 4 AM CDT SATURDAY FOR THE FOLLOWING
ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT
TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT SHOULD EXERCISE CAUTION FROM SATURDAY MORNING
THROUGH SATURDAY AFTERNOON FOR THE FOLLOWING ZONES: WATERS
FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60
NM...WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT
20 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...
WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...38
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
328 PM CDT FRI MAR 28 2014
.DISCUSSION...
AT 2 PM...A WEAK SURFACE LOW WAS LOCATED OVER CENTRAL TEXAS WITH A
WARM FRONT TO THE NORTHEAST...A DRY LINE EXTENDING SOUTH TOWARD
LAREDO AND A COLD FRONT EXTENDING WEST TOWARD THE BIG BEND.
CONVECTION HAS FIRED IN CENTRAL TEXAS THIS AFTERNOON BUT COVERAGE
REMAINS LIMITED. A SOUNDING FROM TEXAS A&M SHOWS A DECENT CAP
BETWEEN 900-800 MB AND CONSIDERABLE DRY AIR AT 800 MB. LOOKS LIKE
TEMPS WILL NEED TO WARM TO AROUND 86 DEGREES TO BREAK THE CAP.
CONVECTION OVER CENTRAL TEXAS WILL CONTINUE TO PUSH EAST AND COULD
HOLD TOGETHER AND MOVE ACROSS THE NORTHERN THIRD OF SE TX. THE
RAP...TEXAS TECH WRF AND HRRR ALL ARE SUPPORTIVE OF CONVECTION
MOVING ACROSS THE NORTH PART OF SE TX THIS EVENING BUT ALL THREE
MODELS HAVE BEEN TOO AGGRESSIVE WITH RAIN CHANCES YESTERDAY AND
AGAIN TODAY. WILL GO WITH LIKELY POPS OVER THE NORTH AND CHANCE
POPS CENTRAL. WILL MENTION SOME STORMS SEVERE OVER THE NORTH.
DENSE SEA FOG CONTINUES ALONG THE COAST. WEB CAMS AND SFC OBS CONT
TO SHOW DENSE SEA FOG IMPINGING ON THE COAST AND OFFSHORE. WILL
PROBABLY NEED A DENSE FOG ADVISORY TONIGHT FOR THE COASTAL
COUNTIES THROUGH 06Z. THE RAP AND GFS ARE FASTER WITH A COLD FRONT
TONIGHT AND IT APPEARS THAT THE FRONT WILL CLEAR THE COAST CLOSER
TO 06Z THAN 12Z SAT. ONCE WINDS GO OFFSHORE...DRIER AIR WILL
FILTER IN AND THE FOG WILL BEGIN TO DISSIPATE. HIGH PRESSURE WILL
DOMINATE SATURDAY AND SUNDAY WITH SEASONAL TEMPS AND PLENTY OF
SUNSHINE.
CLOUDS WILL RETURN LATE SUNDAY NIGHT AND PERSIST THROUGH MUCH OF
THE WEEK AHEAD AS HIGH PRESSURE DRIFTS EAST AND ONSHORE WINDS
PREVAIL. FCST SOUNDINGS SHOW SATURATION BENEATH A CAP SO FEEL
SOME STREAMER SHOWERS WILL BE POSSIBLE STARTING TUESDAY AND
CONTINUING THROUGH FRIDAY. TEMPERATURES WILL ALSO BE MILDER NEXT
WEEK WITH HIGHS NEAR 80 AND LOWS IN THE MID 60S. SOME DIFFERENCES
WITH REGARD TO TIMING OF DISTURBANCES EMBEDDED IN THE UPPER FLOW
SO WILL KEEP RAIN CHANCES ON THE LOW SIDE FOR NOW. GFS/ECMWF WITH
THE TIMING OF THE NEXT COLD FRONT EITHER NEXT FRIDAY OR SATURDAY.
43
&&
.MARINE...
DENSE SEA FOG TO BE THE MAIN ISSUE TONIGHT AS THE NEARSHORE DENSE
DECK CREEPS BACK ONTO THE COAST IN THE COMING HOURS. ANOTHER DENSE
SEA FOG ADVISORY LIKELY IN THE HOURS LEADING UP TO THE COLD FRONT
THAT IS TIMED TO REACH THE SHORELINE AROUND MIDNIGHT...OR SHORTLY
THEREAFTER. THIS FRONTAL PASSAGE WILL SCOUR OUT THE LOWER LEVEL
MOISTURE AND RESIDENT FOG AND CLEAR SKIES THROUGH EARLY SATURDAY
MORNING. LIGHT RAIN OR DRIZZLE WILL ACCOMPANY THIS FOG. POST-FRONTAL
NORTHERLIES OVER THE FAR OFFSHORE WATERS WILL LIKELY INCREASE TO
SCEC CRITERIA FOR A SHORT WHILE SATURDAY MORNING...GENERALLY 15
KNOTS OR LESS OVER THE BAYS AND NEARSHORE WATERS WITH OCCASIONAL 15-
20KT GUSTS OVER A SLIGHT CHOP. AS HIGH PRESSURE MOVES ACROSS FROM
WEST-TO-EAST...LIGHT EASTERLIES WILL SLOWLY VEER SOUTHEASTERLY BY
SUNDAY NIGHT. 31
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 52 78 49 76 53 / 60 10 10 10 0
HOUSTON (IAH) 58 79 52 77 55 / 40 10 10 10 0
GALVESTON (GLS) 64 74 59 73 60 / 20 10 10 10 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...43
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1204 AM CDT FRI MAR 28 2014
.AVIATION...
/06Z TAFS/
CONCERNS...IFR CONDITIONS OVERNIGHT AND THUNDERSTORMS FRIDAY
AFTERNOON. A COLD FRONT ARRIVES LATER ON FRIDAY WITH MVFR CIGS
RETURNING BEHIND THE FRONT.
MVFR AND IFR CEILINGS ARE SPREADING WEST ACROSS NORTH AND CENTRAL
TEXAS. EXPECT ALL TAF SITES TO BE UNDER IFR CIGS BY 07Z TONIGHT.
IN ADDITION...AREAS OF FOG ARE POSSIBLE WITH VISIBILITIES 2-5SM.
CONDITIONS WILL IMPROVE LATE FRIDAY MORNING AS A DRYLINE AND COLD
FRONT ENCROACH ALONG THE I-35 CORRIDOR. THE WINDS IN THE METROPLEX
WILL BEGIN TO TURN TOWARD THE WEST IN THE AFTERNOON HOURS AND THEN
THE FRONT ARRIVES AROUND 22Z. SOUTH WINDS WILL PREVAIL AT KACT
WITH LIGHT WINDS IMMEDIATELY AHEAD OF THE FRONT IN THE LATE
AFTERNOON HOURS WITH FROPA AROUND 29/00Z. KACT COULD SEE SOME
SHOWERS AND POSSIBLY ISOLATED THUNDER BY MID TO LATE FRIDAY
MORNING BUT A STRONG SHORTWAVE WILL BRING A CHANCE FOR
THUNDERSTORMS TO ALL THE AIRPORTS DURING THE AFTERNOON HOURS. SOME
OF THE STORMS COULD BE SEVERE. THE THREAT FOR THUNDER WILL END IN
THE EARLY EVENING HOURS.
82/JLD
&&
.UPDATE...
RAN A QUICK UPDATE TO INCREASE POPS FOR THUNDERSTORM CHANCES
ACROSS THE CWA TOMORROW.
WATER VAPOR SATELLITE IMAGERY WAS TRACKING A COMPACT SHORTWAVE
TROUGH OVER SOUTHERN CALIFORNIA...MOVING EAST TOWARDS ARIZONA AND
NEW MEXICO. THIS TROUGH IS EXPECTED TO SPREAD LARGE SCALE FORCING
FOR ASCENT OVER NORTH TX STARTING AROUND 18Z. CONVECTION THIS
EVENING ACROSS THE CWA WAS LIMITED TO COLLIN COUNTY AND AREAS
NORTHEAST...SO ANY REMNANT OUTFLOW BOUNDARIES ARE EXPECTED TO
REMAIN IN PLACE ACROSS THE NORTHEASTERN CWA...IF THEY DONT JUST
DISSIPATE ALL TOGETHER BY TOMORROW MORNING. THE DRYLINE MADE IT
AS FAR EAST AS A GAINESVILLE TO FORT WORTH TO HAMILTON LINE THIS
AFTERNOON...AND WAS OBSERVED TO BE RETREATING BACK TO THE WEST AT
THE TIME OF THIS DISCUSSION. A COLD FRONT WAS OBSERVED ACROSS EAST
CENTRAL OKLAHOMA...STRETCHING BACK WEST TO THE TEXAS PANHANDLE.
THIS BOUNDARY WAS MOVING SLOWLY SOUTH THIS EVENING...AT AROUND 10
MPH.
THE 00Z NAM AND RAP MODELS WERE CONSISTENT IN SHOWING A LOW-LEVEL
(850 MB) THETA-E RIDGE MOVING NORTHEAST ACROSS THE CWA FROM AROUND
THE MILLS/LAMPASAS COUNTY AREA TOMORROW MORNING. THIS THETA-E
RIDGE WAS MORE OR LESS CONSISTENT WITH THE ZONE OF BEST Q-VECTOR
CONVERGENCE OR POSITIVE PRESSURE ADVECTION ON THE 1.5 PVU SURFACE.
AS A RESULT...THINK THAT THE THETA-E RIDGE IS LIKELY TO BE REAL
AND ASSOCIATED WITH LARGE SCALE FORCING FOR ASCENT BROUGHT ON BY
THE APPROACHING SHORTWAVE TROUGH. THIS THETA-E RIDGE IS EXPECTED
TO EXPAND IN AREAL COVERAGE WHILE MOVING NORTHEAST ACROSS THE
SOUTHEASTERN HALF OF THE CWA TOMORROW MORNING. NON-CONVECTION
ALLOWING OPERATIONAL GUIDANCE CONSISTENTLY HAS ITS CONVECTIVE
PARAMETERIZATION SCHEMES TRIGGERED IN THIS ZONE OF RICH THETA-E
AIR...SO CONFIDENCE IN A MORNING ROUND OF LARGELY UNORGANIZED
THUNDERSTORM ACTIVITY HAS INCREASED. WENT AHEAD AND BUMPED UP POPS
TO 30 PERCENT FOR LOCATIONS ALONG AND SOUTH OF A LAMPASAS TO
HILLSBORO TO PALESTINE LINE TOMORROW MORNING AS A RESULT. SEVERE
WEATHER IS POSSIBLE WITH THIS ACTIVITY...BUT SHOULD REMAIN
ELEVATED IN NATURE LEAVING ONLY A MARGINAL HAIL THREAT DURING THE
MORNING HOURS OF THE DAY.
FOR THE AFTERNOON...THE MORNING CONVECTION...DEPENDING ON HOW
STRONG IT IS...AND HOW LARGE ITS AREAL COVERAGE IS...MAY IMPEDE
AFTERNOON THUNDERSTORM INITIATION. AFTERNOON THUNDERSTORM
INITIATION IS MOST LIKELY ALONG THE DRYLINE...AND THEN AGAIN ALONG
THE COLD FRONT. INITIATION IS DEPENDENT UPON GOOD SOLAR INSOLATION
REMOVING A LOW-LEVEL INVERSION AND MIXING OUT LOW-LEVEL MORNING
STRATUS...ALLOWING FOR SURFACE BASED STORMS. MESOSCALE FORCING FOR
ASCENT ASSOCIATED WITH THE COLD FRONT AND DRYLINE WILL CERTAINLY
SUPPORT STRONG LIFT NEAR THESE BOUNDARIES...HOWEVER FORECAST
SOUNDINGS INDICATE TOO MUCH CONVECTIVE INHIBITION TO BE OVERCOME
BY LIFT ALONE. ASSUMING MORNING CONVECTION EITHER DOES NOT PAN
OUT...OR THAT THE CLOUDS CLEAR OUT SUFFICIENTLY TO ALLOW FOR A FEW
HOURS OF HEATING...THUNDERSTORM INITIATION ALONG THESE BOUNDARIES
CAN BE EXPECTED TO OCCUR AROUND 21Z OR 4 PM CDT.
AT 21Z...THE DRYLINE IS EXPECTED TO BE LOCATED JUST WEST OF THE
INTERSTATE 35 CORRIDOR WITH THE COLD FRONT DROPPING SOUTH TO A
SHERMAN TO FORT WORTH TO CISCO LINE. THIS LEAVES THE TRIPLE POINT
NEAR THE DFW AREA...WHERE THE STRONGEST MESOSCALE FORCING FOR
ASCENT SHOULD OCCUR. WENT AHEAD AND BUMPED POPS UP TO 30 PERCENT
NEAR THESE BOUNDARIES...INCREASING TO 50 PERCENT TO THE EAST AND
SOUTHEAST. WITH THE FAST MOVING NATURE OF THE SHORTWAVE TROUGH AND
ITS ENHANCED MID-UPPER LEVEL WIND SPEEDS...ANY INITIATED STORMS
WOULD TEND TO PULL AWAY FROM THESE BOUNDARIES SOMEWHAT QUICKLY.
HIGH RESOLUTION MODELS INDICATE THE POTENTIAL FOR AROUND 2000 J/KG
OF SURFACE BASED CAPE WITH A DEEP LAYER BULK SHEAR MAGNITUDE OF
AROUND 50 KTS...A BASIC PARAMETER SPACE OVERLAP FAVORING AN
ORGANIZED STORM MODE WITH SUPERCELLS...OR CLUSTERS OF STORMS WITH
EMBEDDED SUPERCELL STRUCTURES.
WHETHER THIS MUCH CAPE CAN BE REALIZED OR NOT DEPENDS LARGELY ON
THE FACTORS DISCUSSED ABOVE...AND WILL BE LARGELY UNKNOWN UNTIL WE
SEE HOW MUCH PRECIPITATION EXISTS TOMORROW MORNING. IF THE CAPE IS
REALIZED...THE PRIMARY SEVERE WEATHER HAZARDS SHOULD BE LARGE HAIL
AND DAMAGING WINDS. A CONDITIONAL TORNADO THREAT IS DEPENDENT UPON
INDIVIDUAL STORMS INTERACTING WITH ANY REMNANT BOUNDARIES TOMORROW
AFTERNOON. OVERALL THE TORNADO THREAT DOES NOT LOOK HIGH FROM THE
SYNOPTIC ENVIRONMENT...BUT WE WILL SEE HOW EVERYTHING EVOLVES
AFTER TOMORROW MORNING. THE THREAT FOR TORNADOES LOOKS LOW FOR NOW
AT LEAST. STORMS SHOULD MOVE EAST OF THE CWA QUICKLY AFTER SUNSET
AS THE SHORTWAVE TROUGH PUSHES EAST...AND THE COLD FRONT BEGINS TO
MOVE QUICKLY ACROSS THE CWA.
CAVANAUGH
&&
.PREV DISCUSSION... /ISSUED 311 PM CDT THU MAR 27 2014/
AN UPPER LEVEL TROUGH CAN BE SEEN ON THE LATEST WATER VAPOR LOOP
LIFTING NORTHEAST FROM THE CENTRAL PLAINS TOWARDS THE GREAT LAKES.
A DEEP SURFACE CYCLONE IS FOLLOWING ALONG A SIMILAR PATH BENEATH
THE UPPER TROUGH...AND THE RESULTING FLOW IS SENDING A COLD FRONT
SOUTHWARD TOWARDS NORTH TEXAS. BOTH THE FRONT AND FORCING FOR
ASCENT ASSOCIATED WITH THE UPPER LEVEL TROUGH WILL REMAIN WELL
NORTH OF NORTH TEXAS THIS EVENING. ANY SURFACE FOCUS FOR
CONVECTION WILL BE ASSOCIATED WITH A DRYLINE...WHICH WAS
ENCROACHING ON THE I-35 CORRIDOR THIS AFTERNOON. ISOLATED
THUNDERSTORMS WILL REMAIN POSSIBLE THROUGH SUNSET THIS EVENING
ALONG THE DRYLINE...WITH THE BETTER CHANCES FOR CONVECTION WELL
EAST OF THE DRYLINE WHERE MOISTURE LEVELS ARE HIGHER AND WEAK
ASCENT FROM THE SOUTHERN EXTENT OF THE PLAINS SYSTEM WILL RESIDE.
THOUGH COVERAGE WILL BE LOW DUE TO VEERING SURFACE WINDS AND A
LINGERING CAP OVERHEAD...CAPE OF 1500 TO 2000 J/KG ENSURES THAT
ANY STORMS THAT DEVELOP COULD BECOME STRONG TO POSSIBLY SEVERE
WITH HAIL AND DAMAGING WINDS. WEST OF THE DRYLINE...HIGH FIRE
DANGER WILL CONTINUE FOR A FEW MORE HOURS BEFORE TEMPERATURES FALL
AND WINDS DECREASE AFTER SUNSET.
THE FRONT WILL CROSS THE RED RIVER TONIGHT AND SAG SLOWLY SOUTH
TO NEAR THE I-20 CORRIDOR AROUND NOON FRIDAY...WITH THE DRYLINE
EXTENDING SOUTHWEST FROM THE FRONT ACROSS THE SOUTHWESTERN
COUNTIES BY NOON FRIDAY AS WELL. THESE BOUNDARIES SHOULD BOTH SERVE
AS A FOCUS FOR CONVECTION AS A SECOND UPPER LEVEL TROUGH PASSES
OVERHEAD. THIS FEATURE IS CURRENTLY OVER SOUTHERN CALIFORNIA AND
WILL MOVE QUICKLY EASTWARD INTO THE DESERT SOUTHWEST
TONIGHT...THEN ACROSS TEXAS TOMORROW. SUFFICIENT INSTABILITY WILL
BE PRESENT ONCE AGAIN WITH SLIGHTLY BETTER UPPER LEVEL SUPPORT IN
PLACE...AND ANY STORM THAT DEVELOPS MAY BECOME STRONG TO POSSIBLE
SEVERE. THE BEST CHANCES WILL AGAIN BE OVER THE EAST AND SOUTHEAST
COUNTIES WHERE THE HIGHEST MOISTURE LEVELS / 1 INCH OR GREATER
PWATS / WILL BE LOCATED. THE EXTENT OF THE CONVECTION IS SOMEWHAT
OF A QUESTION MARK...WITH NAM12 BEING AGGRESSIVE AND THE GFS MUCH
MORE PASSIVE AND FARTHER EAST WITH THE DEVELOPMENT OF SHOWERS AND
THUNDERSTORMS. HIGHER COVERAGE THAN TODAY WOULD MAKE SENSE BASED
ON THE ADDITION OF THE COLD FRONT AND THE CLOSER PROXIMITY OF THE
UPPER LEVEL TROUGH. THIS MAY BE NEGATED THOUGH IF THE UPPER LEVEL
FEATURE MOVES ACROSS PRIOR TO PEAK HEATING...LEAVING US IN THE
SUBSIDENT REGION BY AFTERNOON. WE WILL MAINTAIN THE 40 POPS IN THE
EAST ZONES FOR FRIDAY...LOWERING TO 20 IN THE CENTRAL ZONES
INCLUDING THE DALLAS-FORT WORTH METROPLEX FOR NOW.
THIS SYSTEM WILL MOVE EAST OF THE REGION TOMORROW NIGHT...BRINGING
UPPER RIDGING...WIDESPREAD SUBSIDENCE AND NICE WEATHER TO NORTH
TEXAS FOR THE WEEKEND. PLENTIFUL SUN WILL ALLOW HIGH TEMPERATURES
TO CLIMB INTO THE MID AND UPPER 70S... WITH MOSTLY CLEAR SKIES
ALLOWING NIGHT TIME LOWS TO DROP INTO THE MID AND UPPER 40S. A
WEAK DISTURBANCE WILL MOVE ACROSS THE SOUTHERN PLAINS ON
MONDAY...BRINGING AN INCREASE IN CLOUDS BUT LITTLE IN THE WAY OF
PRECIPITATION. MODELS CONTINUE TO ADVERTISE A STRONGER UPPER
TROUGH DEEPENING OVER THE 4-CORNERS REGION WEDNESDAY...WHICH
SHOULD BRING A DECENT CHANCE OF SHOWERS AND THUNDERSTORMS DURING
THE MIDDLE PART OF NEXT WEEK.
30
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 57 79 48 76 49 / 20 30 30 0 0
WACO, TX 59 82 49 77 48 / 20 50 50 0 0
PARIS, TX 60 76 45 73 45 / 40 20 20 0 0
DENTON, TX 53 77 45 75 44 / 20 20 20 0 0
MCKINNEY, TX 57 78 46 75 45 / 20 30 30 0 0
DALLAS, TX 59 79 49 76 50 / 20 30 30 0 0
TERRELL, TX 60 80 47 75 46 / 30 40 40 0 0
CORSICANA, TX 62 81 49 76 47 / 30 50 50 0 0
TEMPLE, TX 60 82 50 78 48 / 20 50 50 0 0
MINERAL WELLS, TX 51 80 45 77 44 / 10 10 10 0 0
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
82/69
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
746 AM EDT FRI MAR 28 2014
.SYNOPSIS...
A COLD FRONT WILL ENTER OUR REGION BY TONIGHT. ANOTHER AREA OF
LOW PRESSURE WILL RIDE EASTWARD ALONG THE STALLED FRONT FROM THE
MIDDLE MISSISSIPPI VALLEY ON SATURDAY. THIS FRONT WILL EXIT THE
COAST SATURDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 330 AM EDT FRIDAY...
WINDS EARLY THIS MORNING WILL STAY GUSTY OVER THE HIGHER RIDGES AND
THROUGH SOME GAPS ON THE NORTH SIDE OF TWO MOUNTAINS. NOT GETTING
ANY REPORTS OF WIND DAMAGE/POWER OUTAGES...BUT HAD ONE SPOTTER
REPORT GUSTS OVER 50 MPH PER WIND INSTRUMENT. GIVEN LACK OF COVERAGE
OVERALL AND WITH SFC/LOW LVL FLOW STARTING TO VEER MORE TOWARD SOUTH
TO SSW...AN ADVISORY IS NOT NEEDED. OUR TYPICAL WINDIEST PLACES IN
THIS PATTERN HAVE ONLY GUSTED TO 42 MPH IN TAZEWELL COUNTY. AN SPS
WAS ISSUED TO COVER THE HIGHER RIDGES UNTIL THE LOW LVL JET LIFTS
NORTH.
RAIN SHOWERS FORMING ALONG WEAK THETA-E RIDGE AHEAD OF THE MAIN
SYSTEM OVER THE NEW RIVER VALLEY THIS MORNING AND BLUE RIDGE. MAINLY
WILL SEE ISOLATED/SCATTERED COVERAGE EARLY BEFORE MAIN LINE BATCH
MOVES IN AFTER 12Z. STILL NOT SEEING WIDESPREAD COVERAGE BUT ENOUGH
TO WARRANT LIKELY TO CATEGORICAL POPS OVER THE WEST LATER THIS
MORNING...AS THETA-E RIDGE SHIFTS FROM FAR SW VA INTO THE NRN VA
AREA. THE LATEST HRRR IS HANDLING THIS PRETTY WELL IN REGARDS TO
PRECIP AND SHOWS POTENTIAL BREAK IN THE ACTION MID MORNING...AS ONE
AREA OF SHOWERS MOVES INTO THE SHENANDOAH VALLEY...AND THE NEXT AREA
SLIDING NORTHEAST TOWARD THE NC MTNS/FAR SW VA AGAIN BY MIDDAY. WILL
LEAN THIS MORNING POPS THIS WAY...BLENDING TOWARD A GFS/SREF/ECMWF
SOLUTION BY AFTERNOON. GFS DRYING IT FASTER WHICH AGREES WITH THE
00Z WRF/HRRR TO SOME EXTENT AS WELL AS THE 00Z NAM. THIS AFTERNOON
WILL HAVE CHANCE POPS ACROSS THE NRN CWA TO LIKELY IN THE SRN TIER
FROM THE NC MTNS TO SOUTHSIDE VA...WITH POTENTIAL FOR SLIGHT CHANCE
TO NO CHANCE RAIN AROUND 00Z NORTH OF INTERSTATE 64.
TEMPS WILL BE MILD TODAY BUT CLOUDS/RAIN SHOWERS WILL HELP TO KEEP
THEM COOLER THAN NORMAL. MAV/MET BLEND SEEMS TO HANDLE THIS BEST.
LOOK FOR HIGHS FROM THE LOWER TO MID 50S NORTH CAROLINA MTNS/SRN
BLUE RIDGE OF VA TO LOWER TO MID 60S ACROSS THE MTN EMPIRE AS WELL
AS THE PIEDMONTS AND ROANOKE VALLEY.
TONIGHT...A DRYING OUT SOME ALOFT WITH LOW LVL MOISTURE STAYING
CLOSE AT HAND...SO WILL SEE SOME LIGHT RAIN EARLY IN THE SOUTH WITH
MAIN WAVE OF LOW PRESSURE TRACKING TOWARD MID TN/SRN KY BY LATE
TONIGHT. THIS WILL BUCKLE THE FRONT NORTH AGAIN WITH CATEGORICAL
RAIN RETURNING FROM SOUTH TO NORTH OVERNIGHT. MILD LOWS IN THE
40S...LOWER 50S.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AN UPPER LEVEL TROUGH WILL TRACK EAST OVER THE MID WEST
GENERATING A SURFACE LOW THAT WILL TRACK ALONG THE FRONTAL
BOUNDARY SATURDAY MORNING. THE UPPER LEVEL TROUGH WILL START TO
CLOSE OFF SATURDAY AFTERNOON...WITH A NEW SURFACE LOW DEVELOPING
ALONG THE LEE SIDE OF THE SOUTHERN APPALACHIANS. THIS SURFACE LOW
IS EXPECTED TO TRACK ACROSS THE CAROLINA-VIRGINIA PIEDMONT
SATURDAY AFTERNOON/EVENING...THEN OFF THE DELMARVA COAST SATURDAY
NIGHT. THE GFS HAS THE CLOSED UPPER LOW OVER WEST VIRGINIA
SATURDAY EVENING...TRACKING OVER THE FORECAST AREA AND ACROSS
SOUTHERN VIRGINIA SUNDAY MORNING. THE NAM/ECM HAS THE CLOSED LOW
SLIGHTLY FARTHER TO THE SOUTH...TRACKING FROM SOUTHWESTERN
VIRGINIA SATURDAY EVENING...ACROSS NORTH CAROLINA THROUGH THE
MORNING...THEN OFF THE NORTH CAROLINA COAST BY SUNDAY EVENING.
WITH AMPLE MOISTURE AND GOOD JET DYNAMICS...MOST OF SATURDAY WILL BE
WET. THE GOOD NEWS IS THAT IT WILL FALL AS RAIN AND NOT SNOW. AS THE
SECOND LOW TAKES SHAPE AND RACES NORTHEAST OF THE AREA SATURDAY
EVENING...A DRY SLOT WILL TEMPORARILY END THE RAIN SHOWERS. RAIN
SHOWERS RE-ENTERS THE AREA AS THE UPPER LEVEL LOW TRACKS EAST
THROUGH SUNDAY MORNING. TEMPERATURES SHOULD REMAIN WARM ENOUGH ON
THE FRONT END OF THIS LOW TO KEEP P-TYPE AS LIQUID. ON THE BACK
SIDE...COLD AIR AND WRAP-AROUND MOISTURE MAY CHANGE RAIN OVER TO
SNOW/GRAUPEL FOR THE MOUNTAINS...POSSIBLY EAST OF THE BLUE RIDGE
SUNDAY MORNING. CAN NOT RULE OUT A STRIKE OR TWO OF LIGHTNING AS THE
UPPER LOW MOVES OVERHEAD...BUT WILL LEAVE OUT OF THE WEATHER GRIDS
WITH IT TRACKING OVER IN THE MORNING. BY SUNDAY
EVENING...PRECIPITATION WILL BE EAST OF THE AREA...THEN THE WINDS
WILL PICK UP FROM THE NORTH-NORTHWEST. HIGH PRESSURE BUILDS IN
QUICKLY TO CONFINE STRONGEST WINDS TO A 12 HOUR PERIOD
SUNDAY...WEAKENING THROUGH THE NIGHT.
RAINFALL AMOUNTS SATURDAY INTO SATURDAY EVENING WILL RANGE FROM A
THIRD TO THREE-QUARTERS OF AN INCH. IF TODAYS RAIN IS SIGNIFICANT
ENOUGH AND MODELS MAINTAIN SIMILAR QPF TOTALS FOR SATURDAY...A FLOOD
WATCH MAY BE ISSUED. CONFIDENCE IS LOW AT THIS TIME.
CONSIDER WINTERS GRIP ON THE AREA THIS YEAR...HESITANT TO GO WITH A
LITTLE IF ANY SNOWFALL STATEMENT. BOTH THE NAM AND ECM PAINT A
DUSTING TO AN INCH ACROSS THE MOUNTAINS AND INTO THE FOOTHILLS FROM
MIDNIGHT TO NOON SUNDAY. THE GFS IS SIMILAR BUT WITH A 3-4 INCH
BULLEYE CENTERED ON SNOWSHOE WV. WITH THE UPPER LEVEL LOW COMING
OVER DURING THE MORNING...CHANCES ARE GOOD FOR SNOWFALL ESPECIALLY
ACROSS THE WEST. IF THE UPPER LOW IS SLOW TO MOVE ACROSS THE
AREA...THEN WE CAN NOT RULE OUT A COMMON INCH OR TWO ACROSS THE
MOUNTAINS...SLIGHTLY HIGHER AMOUNTS ALONG HIGHER ELEVATIONS.
HOWEVER...MODELS ZIP THE UPPER LOW ACROSS THE FORECAST AREA...WITH A
NARROW BAND OF MOISTURE BEHIND IT...TO KEEP TOTALS UNDER AN INCH.
THERE IS A WIDE RANGE IN GUIDANCE TEMPERATURES FOR SATURDAY. FOR
EXAMPLE...GFSMOS FOR ROANOKE IS 66F WHILE THE NAM IS FORECASTING
50F. THE ECMMOS IS 61F. WITH RAIN EXPECTED FOR MUCH OF THE
DAY...KEPT TEMPERATURES COOL...OBVIOUSLY BETWEEN GUIDANCE...SIMILAR
TO PREVIOUS FORECAST. WITH AN EARLY EXIT OF THE CLOSED
LOW...TEMPERATURES WILL REBOUND QUICKLY SUNDAY AFTERNOON. GUIDANCE
WAS A LITTLE MORE HELPFUL WILL FORECASTED HIGHS AROUND 5F COLDER
THAN NORMAL.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300 PM EST THURSDAY...
LOOKS LIKE MARCH WILL GO OUT LIKE A LAMB AS THE FIRST HALF OF NEXT
WEEK LOOKS DRY. 1024 MB SURFACE HIGH IS PROGGED TO PASS OVHD
MONDAY...FOLLOWED BY A DRY FRONTAL PASSAGE TUESDAY. ASIDE FOR SOME
SCATTERED CLOUDS AND A WIND SHIFT TUESDAY...NO SENSIBLE WEATHER
CHALLENGES ANTICIPATED FOR MONDAY THROUGH WEDNESDAY.
THAT SAID...NOT QUITE AS PRISTINE FROM THE ROCKIES INTO THE UPPER
MID WEST WHERE THE STORM TRACK WILL NOT BE AS FORGIVING. THIS MID
CONUS STORMINESS WILL EVENTUALLY WORK ITS WAY TOWARD THE EAST COAST
BY THE END OF THE WEEK WITH THE BAROCLINIC ZONE SLIDING BACK OUR WAY
WITH THE THREAT FOR UNSETTLED WEATHER FROM THURSDAY INTO NEXT
WEEKEND.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 740 AM EDT FRIDAY...
SCATTERED SHOWERS WILL AFFEC THE AREA THIS MORNING...BECOMING MORE
NUMEROUS IN THE MOUNTAINS...PERHAPS ARRIVING AT LYH BY MIDDAY.
CIGS WILL FLUCTUATE BETWEEN LOW END VFR TO HIGH END MVFR THIS
MORNING THRU THE AFTERNOON. STILL SOME WINDS JUST ABOVE THE
INVERSION OUT OF THE SW GUSTING TO 40 KNOTS...SO KEPT LLWS IN
EARLY BEFORE SHOWERS.
THERE SHOULD BE A BREAK IN THE COVERAGE THIS AFTERNOON...WITH
ACTIVITY PICKING UP AGAIN TONIGHT IN THE SOUTH SPREADING NWD
OVERNIGHT. OVERALL SHOULD SEE SOME GUSTY WINDS MIX DOWN IN THE
ROA/LYH/DAN AREA THIS AFTERNOON WITH WINDS WEAKENING THIS EVENING.
MODELS ARE LOWERING CIGS/VSBYS TO MVFR OR IFR OVERNIGHT WITH RAIN
MOVING BACK IN.
THE LOW MOVES ACROSS SATURDAY WITH MOST SITES REMAIN SUB VFR WITH
RAIN SHOWERS. AN ISOLATED THUNDERSTORM WILL BE POSSIBLE OVER
LYH/DAN SAT AFTERNOON. WINDS PICK UP BEHIND THE LOW SAT NIGHT-
SUNDAY MORNING...BEFORE HIGH PRESSURE WORKS IN FOR MONDAY. LOOK
FOR IMPROVING CIGS/VSBYS SAT NIGHT IN THE EAST AND BY SUNDAY
AFTERNOON IN THE WEST.
DRY WEATHER AND VFR CONDITIONS ARE EXPECTED MONDAY THROUGH
TUESDAY.
&&
.EQUIPMENT...
AS OF 135 AM EDT THURSDAY...
ACCESS TO DATA ON OUR WEB PAGE...WWW.ERH.NOAA.GOV/RNK/...REMAINS
LIMITED DUE TO REGIONAL SERVER ISSUES. THERE IS NO ESTIMATE AT
THIS TIME FOR WHEN IT WILL BE REPAIRED.
OUR NEW...BUT UNFINISHED SITE...WWW.WEATHER.GOV/RNK/ IS OPERATING
PROPERLY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...WP
NEAR TERM...WP
SHORT TERM...RCS
LONG TERM...PM
AVIATION...DS/JC/WP
EQUIPMENT...AMS/WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
436 AM EDT FRI MAR 28 2014
.SYNOPSIS...
A COLD FRONT WILL ENTER OUR REGION BY TONIGHT. ANOTHER AREA OF
LOW PRESSURE WILL RIDE EASTWARD ALONG THE STALLED FRONT FROM THE
MIDDLE MISSISSIPPI VALLEY ON SATURDAY. THIS FRONT WILL EXIT THE
COAST SATURDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 330 AM EDT FRIDAY...
WINDS EARLY THIS MORNING WILL STAY GUSTY OVER THE HIGHER RIDGES AND
THROUGH SOME GAPS ON THE NORTH SIDE OF TWO MOUNTAINS. NOT GETTING
ANY REPORTS OF WIND DAMAGE/POWER OUTAGES...BUT HAD ONE SPOTTER
REPORT GUSTS OVER 50 MPH PER WIND INSTRUMENT. GIVEN LACK OF COVERAGE
OVERALL AND WITH SFC/LOW LVL FLOW STARTING TO VEER MORE TOWARD SOUTH
TO SSW...AN ADVISORY IS NOT NEEDED. OUR TYPICAL WINDIEST PLACES IN
THIS PATTERN HAVE ONLY GUSTED TO 42 MPH IN TAZEWELL COUNTY. AN SPS
WAS ISSUED TO COVER THE HIGHER RIDGES UNTIL THE LOW LVL JET LIFTS
NORTH.
RAIN SHOWERS FORMING ALONG WEAK THETA-E RIDGE AHEAD OF THE MAIN
SYSTEM OVER THE NEW RIVER VALLEY THIS MORNING AND BLUE RIDGE. MAINLY
WILL SEE ISOLATED/SCATTERED COVERAGE EARLY BEFORE MAIN LINE BATCH
MOVES IN AFTER 12Z. STILL NOT SEEING WIDESPREAD COVERAGE BUT ENOUGH
TO WARRANT LIKELY TO CATEGORICAL POPS OVER THE WEST LATER THIS
MORNING...AS THETA-E RIDGE SHIFTS FROM FAR SW VA INTO THE NRN VA
AREA. THE LATEST HRRR IS HANDLING THIS PRETTY WELL IN REGARDS TO
PRECIP AND SHOWS POTENTIAL BREAK IN THE ACTION MID MORNING...AS ONE
AREA OF SHOWERS MOVES INTO THE SHENANDOAH VALLEY...AND THE NEXT AREA
SLIDING NORTHEAST TOWARD THE NC MTNS/FAR SW VA AGAIN BY MIDDAY. WILL
LEAN THIS MORNING POPS THIS WAY...BLENDING TOWARD A GFS/SREF/ECMWF
SOLUTION BY AFTERNOON. GFS DRYING IT FASTER WHICH AGREES WITH THE
00Z WRF/HRRR TO SOME EXTENT AS WELL AS THE 00Z NAM. THIS AFTERNOON
WILL HAVE CHANCE POPS ACROSS THE NRN CWA TO LIKELY IN THE SRN TIER
FROM THE NC MTNS TO SOUTHSIDE VA...WITH POTENTIAL FOR SLIGHT CHANCE
TO NO CHANCE RAIN AROUND 00Z NORTH OF INTERSTATE 64.
TEMPS WILL BE MILD TODAY BUT CLOUDS/RAIN SHOWERS WILL HELP TO KEEP
THEM COOLER THAN NORMAL. MAV/MET BLEND SEEMS TO HANDLE THIS BEST.
LOOK FOR HIGHS FROM THE LOWER TO MID 50S NORTH CAROLINA MTNS/SRN
BLUE RIDGE OF VA TO LOWER TO MID 60S ACROSS THE MTN EMPIRE AS WELL
AS THE PIEDMONTS AND ROANOKE VALLEY.
TONIGHT...A DRYING OUT SOME ALOFT WITH LOW LVL MOISTURE STAYING
CLOSE AT HAND...SO WILL SEE SOME LIGHT RAIN EARLY IN THE SOUTH WITH
MAIN WAVE OF LOW PRESSURE TRACKING TOWARD MID TN/SRN KY BY LATE
TONIGHT. THIS WILL BUCKLE THE FRONT NORTH AGAIN WITH CATEGORICAL
RAIN RETURNING FROM SOUTH TO NORTH OVERNIGHT. MILD LOWS IN THE
40S...LOWER 50S.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AN UPPER LEVEL TROUGH WILL TRACK EAST OVER THE MID WEST
GENERATING A SURFACE LOW THAT WILL TRACK ALONG THE FRONTAL
BOUNDARY SATURDAY MORNING. THE UPPER LEVEL TROUGH WILL START TO
CLOSE OFF SATURDAY AFTERNOON...WITH A NEW SURFACE LOW DEVELOPING
ALONG THE LEE SIDE OF THE SOUTHERN APPALACHIANS. THIS SURFACE LOW
IS EXPECTED TO TRACK ACROSS THE CAROLINA-VIRGINIA PIEDMONT
SATURDAY AFTERNOON/EVENING...THEN OFF THE DELMARVA COAST SATURDAY
NIGHT. THE GFS HAS THE CLOSED UPPER LOW OVER WEST VIRGINIA
SATURDAY EVENING...TRACKING OVER THE FORECAST AREA AND ACROSS
SOUTHERN VIRGINIA SUNDAY MORNING. THE NAM/ECM HAS THE CLOSED LOW
SLIGHTLY FARTHER TO THE SOUTH...TRACKING FROM SOUTHWESTERN
VIRGINIA SATURDAY EVENING...ACROSS NORTH CAROLINA THROUGH THE
MORNING...THEN OFF THE NORTH CAROLINA COAST BY SUNDAY EVENING.
WITH AMPLE MOISTURE AND GOOD JET DYNAMICS...MOST OF SATURDAY WILL BE
WET. THE GOOD NEWS IS THAT IT WILL FALL AS RAIN AND NOT SNOW. AS THE
SECOND LOW TAKES SHAPE AND RACES NORTHEAST OF THE AREA SATURDAY
EVENING...A DRY SLOT WILL TEMPORARILY END THE RAIN SHOWERS. RAIN
SHOWERS RE-ENTERS THE AREA AS THE UPPER LEVEL LOW TRACKS EAST
THROUGH SUNDAY MORNING. TEMPERATURES SHOULD REMAIN WARM ENOUGH ON
THE FRONT END OF THIS LOW TO KEEP P-TYPE AS LIQUID. ON THE BACK
SIDE...COLD AIR AND WRAP-AROUND MOISTURE MAY CHANGE RAIN OVER TO
SNOW/GRAUPEL FOR THE MOUNTAINS...POSSIBLY EAST OF THE BLUE RIDGE
SUNDAY MORNING. CAN NOT RULE OUT A STRIKE OR TWO OF LIGHTNING AS THE
UPPER LOW MOVES OVERHEAD...BUT WILL LEAVE OUT OF THE WEATHER GRIDS
WITH IT TRACKING OVER IN THE MORNING. BY SUNDAY
EVENING...PRECIPITATION WILL BE EAST OF THE AREA...THEN THE WINDS
WILL PICK UP FROM THE NORTH-NORTHWEST. HIGH PRESSURE BUILDS IN
QUICKLY TO CONFINE STRONGEST WINDS TO A 12 HOUR PERIOD
SUNDAY...WEAKENING THROUGH THE NIGHT.
RAINFALL AMOUNTS SATURDAY INTO SATURDAY EVENING WILL RANGE FROM A
THIRD TO THREE-QUARTERS OF AN INCH. IF TODAYS RAIN IS SIGNIFICANT
ENOUGH AND MODELS MAINTAIN SIMILAR QPF TOTALS FOR SATURDAY...A FLOOD
WATCH MAY BE ISSUED. CONFIDENCE IS LOW AT THIS TIME.
CONSIDER WINTERS GRIP ON THE AREA THIS YEAR...HESITANT TO GO WITH A
LITTLE IF ANY SNOWFALL STATEMENT. BOTH THE NAM AND ECM PAINT A
DUSTING TO AN INCH ACROSS THE MOUNTAINS AND INTO THE FOOTHILLS FROM
MIDNIGHT TO NOON SUNDAY. THE GFS IS SIMILAR BUT WITH A 3-4 INCH
BULLEYE CENTERED ON SNOWSHOE WV. WITH THE UPPER LEVEL LOW COMING
OVER DURING THE MORNING...CHANCES ARE GOOD FOR SNOWFALL ESPECIALLY
ACROSS THE WEST. IF THE UPPER LOW IS SLOW TO MOVE ACROSS THE
AREA...THEN WE CAN NOT RULE OUT A COMMON INCH OR TWO ACROSS THE
MOUNTAINS...SLIGHTLY HIGHER AMOUNTS ALONG HIGHER ELEVATIONS.
HOWEVER...MODELS ZIP THE UPPER LOW ACROSS THE FORECAST AREA...WITH A
NARROW BAND OF MOISTURE BEHIND IT...TO KEEP TOTALS UNDER AN INCH.
THERE IS A WIDE RANGE IN GUIDANCE TEMPERATURES FOR SATURDAY. FOR
EXAMPLE...GFSMOS FOR ROANOKE IS 66F WHILE THE NAM IS FORECASTING
50F. THE ECMMOS IS 61F. WITH RAIN EXPECTED FOR MUCH OF THE
DAY...KEPT TEMPERATURES COOL...OBVIOUSLY BETWEEN GUIDANCE...SIMILAR
TO PREVIOUS FORECAST. WITH AN EARLY EXIT OF THE CLOSED
LOW...TEMPERATURES WILL REBOUND QUICKLY SUNDAY AFTERNOON. GUIDANCE
WAS A LITTLE MORE HELPFUL WILL FORECASTED HIGHS AROUND 5F COLDER
THAN NORMAL.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300 PM EST THURSDAY...
LOOKS LIKE MARCH WILL GO OUT LIKE A LAMB AS THE FIRST HALF OF NEXT
WEEK LOOKS DRY. 1024 MB SURFACE HIGH IS PROGGED TO PASS OVHD
MONDAY...FOLLOWED BY A DRY FRONTAL PASSAGE TUESDAY. ASIDE FOR SOME
SCATTERED CLOUDS AND A WIND SHIFT TUESDAY...NO SENSIBLE WEATHER
CHALLENGES ANTICIPATED FOR MONDAY THROUGH WEDNESDAY.
THAT SAID...NOT QUITE AS PRISTINE FROM THE ROCKIES INTO THE UPPER
MID WEST WHERE THE STORM TRACK WILL NOT BE AS FORGIVING. THIS MID
CONUS STORMINESS WILL EVENTUALLY WORK ITS WAY TOWARD THE EAST COAST
BY THE END OF THE WEEK WITH THE BAROCLINIC ZONE SLIDING BACK OUR WAY
WITH THE THREAT FOR UNSETTLED WEATHER FROM THURSDAY INTO NEXT
WEEKEND.
&&
.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
AS OF 140 AM EDT FRIDAY...
EXPECT VFR CONDITIONS THIS MORNING. HOWEVER...THERE WILL BE LOW
LEVEL WIND SHEAR PRIOR TO SHOWERS ARRIVING AT ALL TERMINALS BUT
BLF WHERE THEY WILL BE MIXING ABOVE THE INVERSION.
CIGS WILL LOWER THROUGH THE MORNING WITH SHOWERS ENTERING BLF/LWB
FIRST AROUND 10Z...REACHING BCB/ROA 11-12Z AND MAKING IT TOWARD
LYH/DAN 13-15Z.
THERE WILL BE PERIODS OF MODERATE SHOWERS WHICH COULD TAKE THE
VSBY DOWN TO MVFR...BUT AMOUNT OF TIME THIS OCCURS WILL BE LESS
THAN TEMPO GROUPS PROVIDE EXCEPT BCB IN THE 12-14Z.
THIS AFTERNOON...THE MAIN AREA OF SHOWERS WILL BE SHIFTING SE OF
THE AREA...BUT WILL STILL SEE SPOTTY SHOWERS AROUND...BUT AGAIN
TOUGH TO PINPOINT WHEN AND IF IT WILL HIT ANY TAF SITES. SHOULD
SEE SOME MVFR IMPROVE BACK TO VFR THIS AFTERNOON AS WELL.
THE NEXT UPSTREAM WAVE OF LOW PRESSURE WILL BUCKLE THE FRONT
TOWARD THE NORTH...AND MODELS FAVOR A RETURN TO EITHER LIGHT
RAIN/DRIZZLE AT MOST SITES FRIDAY EVENING WITH CIGS DROPPING BACK
TO LOW END MVFR AND SOME IFR.
ANOTHER STRONGER COLD FRONT WILL MOVE THROUGH THE REGION ON
SATURDAY. THERE WILL BE BETTER CHANCE FOR SOME ISOLATED TO
SCATTERED THUNDERSTORMS BE ASSOCIATED WITH THE FRONT. AGAIN...MOST
AREAS WILL REMAIN VFR OUTSIDE THE STRONGER CELLS ALONG THE FRONT.
SATURDAY NIGHT INTO SUNDAY...STRONG NORTHWEST WINDS ARE EXPECTED
AS THE PARENT UPPER LOW MAKES ITS WAY ACROSS THE AREA. UPSLOPE
SHOWERS ARE POSSIBLE ALONG A KLWB-KBLF LINE INTO SUNDAY. DRY
WEATHER AND VFR CONDITIONS ARE EXPECTED MONDAY THROUGH TUESDAY.
&&
.EQUIPMENT...
AS OF 135 AM EDT THURSDAY...
ACCESS TO DATA ON OUR WEB PAGE...WWW.ERH.NOAA.GOV/RNK/...REMAINS
LIMITED DUE TO REGIONAL SERVER ISSUES. THERE IS NO ESTIMATE AT
THIS TIME FOR WHEN IT WILL BE REPAIRED.
OUR NEW...BUT UNFINISHED SITE...WWW.WEATHER.GOV/RNK/ IS OPERATING
PROPERLY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...WP
NEAR TERM...WP
SHORT TERM...RCS
LONG TERM...PM
AVIATION...DS/JC/WP
EQUIPMENT...AMS/WP
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1044 PM CDT SAT MAR 29 2014
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 248 PM CDT SAT MAR 29 2014
THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW HIGH
PRESSURE STRETCHING FROM QUEBEC TO THE WESTERN GREAT LAKES TO THE
STATE OF TEXAS. EARLIER RIBBON OF STRATO-CU OVER PARTS OF CENTRAL
AND NORTHEAST WISCONSIN DISSIPATED AROUND MIDDAY LEAVING MOSTLY
SUNNY CONDITIONS ACROSS THE NORTHERN HALF OF THE STATE. LOOKING
UPSTREAM...THE JET IS PUSHING MID AND HIGH CLOUDS TO THE EAST ACROSS
THE PLAINS. BUT OTHERWISE QUIET CONDITIONS EXIST UNTIL NORTHWEST
MONTANA IN THE VICINITY OF SHORTWAVE ENERGY. WITH THAT SHORTWAVE
EXPECTED TO PASS NORTH OF THE REGION...THE MAIN FORECAST CONCERNS
INCLUDE CLOUDS AND TEMPS IN THE SHORT TERM.
TONIGHT...SURFACE HIGH PRESSURE WILL SHIFT FROM THE WESTERN TO THE
CENTRAL GREAT LAKES WHILE THE MID-LEVEL RIDGE AXIS WORKS ACROSS THE
STATE. SHORTWAVE ENERGY MOVING ACROSS SOUTHERN CANADA WILL SEND MID
AND HIGH CLOUDS ACROSS NORTHERN MINNESOTA AND LAKE SUPERIOR. BUT
SOME OF THESE CLOUDS WILL LIKELY GRAZE NORTHERN WISCONSIN.
OTHERWISE...MOSTLY CLEAR TO CLEAR CONDITIONS WILL PREVAIL.
DEVELOPING SOUTHEAST WINDS WILL LIKELY TEMP KEEPS FROM PLUMMETING
OVER THE DEEP SNOW PACK OF N-C WISCONSIN. TEMPS MAINLY IN THE
20...EXCEPT FOR A FEW TEENS OVER FAR NE WISCONSIN.
SUNDAY...RETURN FLOW WILL BE RAMPING UP THROUGH THE DAY AS LOW
PRESSURE EMERGES INTO THE CENTRAL PLAINS. AT THE SAME TIME...A COLD
FRONT WILL BE SAGGING SOUTHEAST ACROSS MINNESOTA AND INTO FAR NW
WISCONSIN BY LATE IN THE AFTERNOON. SOUTH TO SOUTHEAST WINDS WILL
BE ADVECTING WARMER AIR IN THE LOW LEVELS WHICH WILL LEAD TO A
WARMER DAY ACROSS THE REGION. THE EXCEPTION WILL BE ALONG THE LAKE
AND BAY SHORE WHERE ONSHORE FLOW WILL PUSH IN A COLD MARINE LAYER.
SO WILL GO WITH HIGHS IN THE UPPER 50S IN THE WARM SPOTS...TO THE
UPPER 30S ALONG LAKE MICHIGAN. SHOULD SEE MORE IN THE WAY OF MID
AND HIGH CLOUDS WHICH WILL PROVIDE FILTERED SUNSHINE AT TIMES...BUT
DO NOT THINK THEY WILL HAVE MUCH IMPACT ON TEMPS.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 248 PM CDT SAT MAR 29 2014
THE MODELS ARE NOW IN FAIRLY GOOD AGREEMENT THAT THE SYSTEM MOVING
OUT OF THE CENTRAL PLAINS WILL TRACK TO THE WEST OF OUR FORECAST
AREA...RESULTING IN MOSTLY RAIN AND A CHANCE OF THUNDERSTORMS. THE
RAIN SHOULD ARRIVE FROM WEST TO EAST MONDAY AFTERNOON AND CONTINUE
MONDAY NIGHT. COLDER AIR AND SNOW SHOWERS ARE LIKELY TUESDAY. THE
MAIN CONCERN FROM THE RAIN AND WARMER TEMPERATURES IS MELTING SNOW
AND RIVER ICE WITH THE POSSIBILITY OF LOCAL FLOODING. HIGH
PRESSURE BUILDS IN TUESDAY NIGHT AND WEDNESDAY BEFORE ANOTHER
SYSTEM APPROACHES FROM THE SOUTHERN PLAINS. THE GFS IS MUCH FASTER
AND FLATTER WITH THE SURFACE SYSTEM AND WE WOULD BE IN THE
NORTHERN FRINGE OF IT AND RECEIVE SOME SNOW WHILE THE ECMWF IS
SLOWER AND STRONGER AND WE WOULD HAVE PRECIPITATION TYPE ISSUES
DUE TO A MORE NORTHERLY TRACK. THEN A LITTLE COLDER AND DRY
WEATHER EXPECTED FRIDAY AND SATURDAY.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1040 PM CDT SAT MAR 29 2014
CLEAR SKIES COVERED NORTHEAST WISCONSIN LATE THIS EVENING. VFR
CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD...WITH AN INCREASE
IN MID-LEVEL CLOUDS EXPECTED BY SUNDAY MORNING. SOME STRATOCUMULUS
MAY DEVELOP IN NC/C WI SUNDAY EVENING...BUT CIGS SHOULD BE
4000-6000 FT. INCREASING SOUTH FLOW WILL RESULT IN GUSTS TO NEAR
20 KTS SUNDAY AFTERNOON. AS SFC WINDS DECREASE AND WINDS ALOFT
INCREASE ON SUNDAY EVENING...SOME MARGINAL LLWS SHOULD DEVELOP AT
ALL OF THE TAF SITES.
&&
.HYDROLOGY...
ISSUED AT 248 PM CDT SAT MAR 29 2014
WARMER TEMPERATURES...MELTING SNOW AND RAIN WILL PRODUCE AN
INCREASE IN THE CHANCES OF LOCAL FLOODING EARLY NEXT WEEK. THE SNOW
IS VERY DEEP IN THE NORTH AND SHOULD BE ABLE TO ABSORB THE
RAINFALL WITHOUT FULLY MELTING BUT PLACES WITH JUST A FEW INCHES
LEFT MAY HAVE MOST OF IT MELT AND RUN OFF THE FROZEN GROUND INTO
RIVERS AND STREAMS. THERE IS ALSO A CHANCE OF ICE JAMS AS RIVER
ICE BREAKS UP. WE HAVE A HYDROLOGICAL OUTLOOK IN EFFECT.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......KIECKBUSCH
HYDROLOGY......RDM
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
346 PM CDT FRI MAR 28 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 346 PM CDT FRI MAR 28 2014
AT 3 PM...WATER VAPOR SHOWED A WEAKENING SHORT WAVE TROUGH MOVING
INTO SOUTHWEST MINNESOTA...AND MORE IMPRESSIVE SHORT WAVE MOVING
THROUGH SOUTHERN MISSOURI. THE 28.00Z MODELS ARE IN GENERAL
AGREEMENT THAT THE NORTHERN SYSTEM WILL CONTINUE TO WEAK TONIGHT
AND THE SOUTHERN STREAM SYSTEM WILL REMAIN THE DOMINANT SYSTEM.
THESE 2 SYSTEMS EVENTUALLY MERGE ACROSS CENTRAL ILLINOIS AND
INDIANA WITH AN INVERTED TROUGH EXTENING NORTHWEST TOWARD
NORTHEAST IOWA AND SOUTHWEST WISCOSNIN. WITH NORTHERLY FLOW
BRINGING DRIER AIR INTO THE REGION...THIS TROUGH WILL HAVE VERY
LITTLE MOISTURE TO WORK WITH. AS A RESULT...JUST EXPECT SOME
CLOUDS WITH THIS SYSTEM FOR TONIGHT AND EARLY SATURDAY MORNING.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 346 PM CDT FRI MAR 28 2014
ON SUNDAY...THERE IS A BIT OF CONCERN ON THE HIGH TEMPERATURES.
MUCH OF THIS HAS TO DEAL WITH THE SPEED OF THE SYSTEM EJECTING OUT
OF THE CENTRAL PLAINS. THE NAM IS MUCH FASTER AT EJECTING THIS
SYSTEM TOWARD THE REGION...THUS...THE SOUTHERLY WINDS ARE MUCH
STRONGER ACROSS THE AREA. MEANWHILE THE GFS...GEM...AND ECMWF ARE
WEAKER WITH THESE SOUTHERLY WINDS. IN ADDITION...THESE MODELS
ALLOW A CANADIAN COLD FRONT DROP A BIT FURTHER SOUTH INTO THE
FORECAST AREA. AS A RESULT...THERE IS SOME CONCERN THAT
TEMPERATURES MAY NOT GET AS WARM NORTH OF THE INTERSTATE 90
CORRIDOR. SINCE THE CONSENSUS WAS TO GO WITH THE LATTER
MODELS...COOLED THE HIGH TEMPERATURES A BIT NORTH OF INTERSTATE
90.
FROM SUNDAY NIGHT INTO MONDAY NIGHT...BOTH THE GEM AND ECWMF HAVE
SLOWED THEIR MOVEMENT OF THE SURFACE LOW AND STRONG NEGATIVELY
TILTED SHORT WAVE TROUGH THE REGION. THEY ARE NOW MUCH CLOSER TO
THE GFS SOLUTION WHICH DOES NOT MOVE THESE SYSTEM THROUGH THE AREA
UNTIL THE LATE AFTERNOON AND EVENING. THIS SLOW DOWN IS NOTHING
UNUSUAL WITH SOUTHWEST SYSTEMS AND WOULD NOT BE SURPRISED TO SEE
SOME MORE SLOWING WITH THIS SYSTEM. MEANWHILE THE NAM/WRF HAS A
SLIGHTLY WEAKER WAVE WAVE ALOFT AND THE SURFACE LOW MOVES QUICKLY
NORTHEAST THROUGH THE AREA ON MONDAY NIGHT. THIS MODEL APPEARS TO
BE AN OUTLIER...SO IT WAS NOT USED FOR THIS TIME PERIOD. WHILE THE
GFS...GEM...AND ECMWF ARE IN GOOD AGREEMENT WITH OVER 50 KNOTS OF
0-6 KM SHEAR AND HELICITIES OF OVER 500 WITH THIS WAVE...THEY
DIFFER ON THE MOST UNSTABLE CAPE ACROSS THE REGION. THE GFS HAS
MUCH MORE PRECIPITATION IN THE WARM SECTOR OF THIS SYSTEM /WHICH
COVERS THE SOUTHERN 2/3RDS OF THE FORECAST AREA/. AS A RESULT...IT
HAS VERY LITTLE CAPE. THE ECWMF HAS A SLIGHTLY MORE CLEANER OF THE
WARM SECTOR OF THIS SYSTEM PRIOR TO THE COLD FRONT...THUS...IT HAS
SLIGHTLY GREATER MOST UNSTABLE CAPES /UP TO 300 J/KG/. THE GEM HAS
VERY LITTLE CONVECTION IN THE WARM SECTOR PRIOR TO THE COLD FRONT.
THIS ALLOWS THE MOST UNSTABLE CAPES TO CLIMB UP TO 700 J/KG. WITH
THIS LATTER SCENARIO...THERE WOULD BE MORE CONCERN ABOUT THE
POTENTIAL FOR SUPER CELL THUNDERSTORMS. WHILE THERE IS STILL A LOT
OF UNCERTAINTY ON THE SEVERE WEATHER THREAT...THE STRENGTH OF THIS
SYSTEM AND THE POTENTIAL FOR SLANTWISE AND UPRIGHT CONVECTION
LOOKS TO BE ENOUGH TO WARRANT AT LEAST THE MENTION OF THUNDER
ACROSS THE ENTIRE FORECAST AREA FROM MONDAY AFTERNOON INTO MONDAY
EVENING. IN ADDITION WITH THE SLOWER MOVEMENT INTO THE
AREA...INCREASED MONDAY HIGH TEMPERATURES AND MONDAY NIGHT LOW
TEMPERATURES ACROSS THE NORTHEAST IOWA AND WESTERN WISCONSIN.
FROM TUESDAY NIGHT THROUGH FRIDAY...THE 28.12Z MODELS CONTINUE TO
STRUGGLE WITH THE TRACK OF 2 LOW PRESSURE SYSTEMS THROUGH THE MID
AND UPPER MISSISSIPPI RIVER VALLEY. THE ECWMWF HAS SHIFTED FURTHER
NORTH...RESULTING IN MORE OF A RAIN SOLUTION FOR THE AREA.
MEANWHILE THE GFS AND GEM HAVE A MUCH MORE ACTIVE SOUTHERN STREAM
SYSTEM. AS A RESULT...THERE IS MORE OF A MIX FOR THE WEDNESDAY
THROUGH THURSDAY...AND THE SYSTEM FOR THURSDAY NIGHT AND FRIDAY
WILL BE SOUTH OF THE AREA. DUE TO THIS POOR MODEL CONSISTENCY AND
AGREEMENT...JUST STAYED WITH MODEL CONSENSUS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1241 PM CDT FRI MAR 28 2014
MAIN AVIATION CONCERN IS MVFR STRATUS DECK SOUTH OF TAF SITES TO
PERSIST THIS AFTERNOON. LATEST 28.12Z NAM AND 28.15Z RAP NOT
HANDLING THE ERODING OF LOW STRATUS DECK/MOISTURE WELL PER LATEST
VISIBLE SATELLITE IMAGERY. WITH DRY NORTHERLY FLOW AND SUBSIDENCE
UNDER SURFACE HIGH OVER NORTHERN MINNESOTA...EXPECT THE
MVFR/STRATUS DECK TO DIMINISH ON NORTHERN PERIPHERY AND PRODUCE A
SCATTER DECK OF 2500 TO 3500 FEET AT THE RST/LSE TAF SITES THIS
AFTERNOON. WEAK LOW PRESSURE WILL MOVE INTO THE CENTRAL PLAINS
STATES THIS AFTERNOON/TONIGHT AND SPREAD A MID DECK(ABOVE 10K
FEET) OF CLOUDS OVER THE TAF SITES. THE 28.12Z GFS/NAM BUFKIT
SOUNDINGS ARE SHOWING AN INVERSION DEVELOPING TONIGHT AND
MOISTENING UP THE NEAR SURFACE BOUNDARY LAYER. THIS MOISTURE LOOKS
OVERDONE...AS REGION WILL BE UNDER THE INFLUENCE OF SURFACE HIGH
OVER NORTHERN WISCONSIN. EXPECT VFR CONDITIONS TO PREVAIL AT BOTH
LSE/RST TAF SITES TONIGHT THROUGH THE REST OF THE TAF PERIOD.
&&
.HYDROLOGY...
ISSUED AT 346 PM CDT FRI MAR 28 2014
MINOR FLOODING IS EXPECTED TO CONTINUE INTO SATURDAY ALONG PARTS
OF KICKAPOO AS RUNOFF FROM LAST NIGHT/S RAINFALL WORKS ITS WAY
DOWN THE RIVER.
FROM SUNDAY INTO MONDAY NIGHT...THE RAPID WARM UP WILL CAUSE THE
SNOW PACK NORTH OF INTERSTATE 94 TO MELT RAPIDLY. IN
ADDITION WITH FROZEN GROUND...ADDITIONAL RAINFALL ON MONDAY AND
MONDAY NIGHT WILL QUICKLY RUNOFF INTO AREA RIVERS AND STREAMS. THIS
WILL RESULT IN RISES ALONG THE BLACK...BUFFALO...AND TREMPEALEAU
RIVERS IN WESTERN WISCONSIN. THERE IS A DISTINCT POSSIBILITY THAT
THERE WILL BE THE POTENTIAL FOR SOME FLOODING ALONG THESE RIVERS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...DTJ
HYDROLOGY...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1241 PM CDT FRI MAR 28 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 311 AM CDT FRI MAR 28 2014
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING ALONG THE U.S. WEST COAST INTO BRITISH COLUMBIA...A
PACIFIC SHORTWAVE OVER WYOMING...A VIGOROUS PACIFIC SHORTWAVE NEAR
DAVENPORT IA...AND A POLAR SHORTWAVE OVER LAKE WINNIPEG. THE
DAVENPORT IA SHORTWAVE...IN COMBINATION WITH PRECIPITABLE WATER
VALUES OF 0.6-0.9 INCHES / 200 PERCENT OF NORMAL / AND FRONTOGENESIS
HELPED PRODUCE PRECIPITATION ACROSS MUCH OF THE FORECAST AREA
YESTERDAY TO AROUND MIDNIGHT. MUCH OF THIS PRECIPITATION FELL AS
RAIN...WHICH WITH FROZEN GROUND HAS LED TO PLENTY OF RUNOFF AND
RISES ON AREA RIVERS AND STREAMS. SEE THE HYDROLOGY SECTION FOR MORE
INFORMATION. SOME OF THE PRECIPITATION FELL AS SNOW...MAINLY IN
NORTHWEST TO NORTH SECTIONS OF THE AREA...WITH THE MOST IN TAYLOR
COUNTY. LOW LEVEL CYCLONIC FLOW AROUND LOW PRESSURE OVER CENTRAL
LAKE MICHIGAN HAS KEPT CLOUDS IN PLACE THROUGH THE NIGHT...THOUGH
CLEARING WAS EVIDENT OVER THE NORTHWEST HALF OF MINNESOTA.
PRECIPITABLE WATER AT BIS WAS QUITE LOW WITH THE RIDGE...0.17 INCHES
AT BIS AND ABR OR 50-60 PERCENT OF NORMAL. COLDER AIR WAS ALSO
FILTERING IN...REFLECTING A CANADIAN RIDGE OF HIGH PRESSURE BUILDING
SOUTH INTO THE UPPER MIDWEST. FARTHER TO THE WEST...CLOUDS AND SOME
SCATTERED LIGHT PRECIPITATION WAS OCCURRING OVER WYOMING WITH THE
SHORTWAVE THERE.
AFTER AN ACTIVE PERIOD OF PRECIPITATION THE PAST 24 HOURS...THIS
SHORT TERM PERIOD LOOKS MUCH QUIETER. FOCUS FOR ANY POTENTIAL
PRECIPITATION WOULD BE ON THE SHORTWAVE OVER WYOMING...WHICH IS
PROGGED BY MODELS TO CROSS THE FORECAST AREA TONIGHT. HOWEVER...
THERE ARE 2 ITEMS GOING AGAINST PRECIPITATION... 1. ANOTHER
SHORTWAVE COMING OUT OF ARIZONA IS SUGGESTED TO INTENSIFY AND DEEPEN
AS IT REACHES MISSOURI TONIGHT...ROBBING THE WYOMING SHORTWAVE OF
MOISTURE. 2. THE WYOMING SHORTWAVE WILL BE HEADING INTO A DRY
AIRMASS AS SEEN ON THE BIS/ABR SOUNDINGS. MODELS CONTINUE TO DEPICT
THAT ANY PRECIPITATION WITH THE SHORTWAVE WILL DRY UP BEFORE THE
SHORTWAVE GETS TO THE FORECAST AREA...THUS STAYED WITH A DRY
FORECAST.
CLOUDS AND TEMPERATURES NOW BECOME THE MAIN CONCERNS. LOW CLOUDS
LOOK TO QUICKLY EXIT OFF TO THE EAST THIS MORNING AS THE DRIER AIR
TO OUR NORTHWEST ADVECTS IN. SCT-BKN MID AND HIGH CLOUDS WILL THEN
TRAVERSE THE AREA THIS AFTERNOON THROUGH TONIGHT AS THE WYOMING
SHORTWAVE MOVES THROUGH. 925MB TEMPS ARE PROGGED BETWEEN -2 TO -6C
AT 18Z...THOUGH MORE SUN TODAY WILL HELP TO COUNTERACT SOME OF THE
COLDER AIR. IN FACT...OVER THE SNOW FREE AREAS...TEMPERATURES MAY
EVEN END UP A LITTLE WARMER THAN YESTERDAY. ALTHOUGH SURFACE WINDS
LOOK LIGHT TONIGHT...THE CLOUDS SHOULD HELP TO HOLD READINGS UP FROM
THE MID TEENS TO MID 20S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 311 AM CDT FRI MAR 28 2014
MUCH OF THE LONG TERM PERIOD FOCUSES ON AN IMPRESSIVE LONG WAVE
TROUGH SITTING OVER THE EASTERN PACIFIC. ALL MODELS SHOW THAT A
POTENT SHORTWAVE WILL COME OUT OF THIS TROUGH AND TRACK INTO THE
FORECAST AREA FOR MONDAY. THEN THE ENTIRE TROUGH LOOKS TO COME INTO
THE WESTERN U.S. ON TUESDAY...TRACKING INTO THE CENTRAL PLAINS ON
THURSDAY.
MUCH OF FRIDAY NIGHT THROUGH SUNDAY LOOKS TO BE DOMINATED BY
BUILDING RIDGING AHEAD OF THE POTENT SHORTWAVE MARCHING ACROSS THE
WESTERN U.S.. NO CONCERNS FOR PRECIPITATION DURING THIS PERIOD AS
THE FORECAST AREA TRANSITIONS FROM UNDER DOMINANCE OF HIGH PRESSURE
TO INTO THE WARM SECTOR OF A DEEPENING SURFACE CYCLONE OVER
NORTHEAST COLORADO. TEMPERATURES AND WINDS ARE THE MAIN ISSUES.
925MB TEMPS ARE PROGGED SLIGHTLY WARMER ON SATURDAY...0 TO -
4C...WHICH WITH WHAT LOOKS TO BE PLENTY OF SUN SHOULD HELP BOOST
TEMPS INTO THE 40S...PERHAPS EVEN AROUND 50 IN SOME VALLEY
LOCATIONS. SOUTH TO SOUTHWEST WINDS REALLY PICK UP SATURDAY
NIGHT...UPWARDS OF 40-50 KT BY 12Z SUN AT 925MB...CAUSING 925-850MB
TEMPS TO REALLY CLIMB. ANTICIPATING LOWS IN THE EVENING SATURDAY
NIGHT...THEN HOLD STEADY TO SLOWLY RISE AS THE WARM AIR SURGES IN.
THE CLIMB CONTINUES THROUGH SUNDAY AS THE 925MB TEMPS CLIMB TO AS
MUCH AS 10-13C BY 00Z MONDAY. 400-250MB RH PROGS SUGGESTS PLENTY OF
SCT-BKN CIRRUS...BUT THE SUN AND WARM 925MB TEMPS SHOULD HELP PROPEL
READINGS INTO THE FIRST 60S OF THE YEAR FOR MOST LOCATIONS. MORE
SNOWPACK OVER TAYLOR/CLARK WILL HOLD READINGS BACK THERE INTO THE
50S...THOUGH THIS SNOWPACK IS GOING TO MELT FAST GIVEN THE WARM AIR
AND BREEZY CONDITIONS...YIELDING HYDRO CONCERNS. SEE HYDROLOGY
SECTION.
ATTENTION THEN TURNS TO THE POTENT SHORTWAVE HEADING INTO THE
FORECAST AREA FOR MONDAY. BOTH THE GFS AND ECMWF HAVE REALLY SLOWED
AND DEEPENED THIS SHORTWAVE AND THE ASSOCIATED SURFACE LOW OVER THE
PAST 24-48 HOURS. THIS RESULTS IN THE FORECAST AREA STAYING IN THE
WARM SECTOR LONGER AND THUS WARMER CONDITIONS ARE FORECAST FOR
SUNDAY NIGHT AND MONDAY. THERE ARE A COUPLE OF PRECIPITATION IMPACTS
TOO. FIRST...THE DEFORMATION BAND ON THE NORTHWEST SIDE OF THE LOW
NOW ONLY LOOKS TO IMPACT THE NORTHWEST HALF OF THE AREA MONDAY
AFTERNOON AND NIGHT...THOUGH IT MAY STAY ENTIRELY NORTHWEST OF THE
FORECAST AREA. SECOND...A LEAD WAVE OF RAIN RESULTING FROM
ISENTROPIC LIFT IS LOOKING LIKELY TO PROGRESS ACROSS THE FORECAST
AREA LATE SUNDAY NIGHT THROUGH EARLY MONDAY AFTERNOON. THIRD...THE
SYSTEMS COLD FRONT AND STRONG DYNAMICS ARE PROGGED TO MOVE THROUGH
MONDAY AFTERNOON AND EVENING. THERE IS A CAP TO BE OVERCOME...BUT
WITH SUCH STRONG FORCING...CANNOT RULE OUT A BAND OF SHOWERS AND
STORMS FIRING ON THE FRONT. SHOULD STORMS FORM...WHICH IS A BIG
IF...THERE IS AMPLE SHEAR TO SUPPORT SEVERE. WE WILL NEED TO KEEP AN
EYE ON INSTABILITY VERSUS CAPPING FOR MONDAY AFTERNOON.
TUESDAY INTO TUESDAY NIGHT LOOK TO BE QUIET AND MUCH COLDER...THEN
WEATHER GETS ACTIVE AGAIN FOR WEDNESDAY INTO THURSDAY AS THE REST OF
THE UPPER TROUGH LIFTS TOWARDS THE REGION. THIS TIME AROUND...WE MAY
HAVE TO DEAL WITH A WINTRY MIX SIDE DUE TO WARM/MOIST ADVECTION
ALOFT AND A FLOW OF DRY AIR AND COLD ADVECTION AT THE SURFACE.
THEN...IF THE 28.00Z ECMWF IS CORRECT...WE WILL AT LEAST CHANGE OVER
TO ALL RAIN AND PERHAPS BRING MORE THUNDERSTORMS. NEEDLESS TO
SAY...PLENTY OF UNCERTAINTY OUT THIS FAR AND THUS STAYED WITH A
MODEL CONSENSUS FOR NOW. CERTAINLY ANOTHER ITEM TO WATCH.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1241 PM CDT FRI MAR 28 2014
MAIN AVIATION CONCERN IS MVFR STRATUS DECK SOUTH OF TAF SITES TO
PERSIST THIS AFTERNOON. LATEST 28.12Z NAM AND 28.15Z RAP NOT
HANDLING THE ERODING OF LOW STRATUS DECK/MOISTURE WELL PER LATEST
VISIBLE SATELLITE IMAGERY. WITH DRY NORTHERLY FLOW AND SUBSIDENCE
UNDER SURFACE HIGH OVER NORTHERN MINNESOTA...EXPECT THE
MVFR/STRATUS DECK TO DIMINISH ON NORTHERN PERIPHERY AND PRODUCE A
SCATTER DECK OF 2500 TO 3500 FEET AT THE RST/LSE TAF SITES THIS
AFTERNOON. WEAK LOW PRESSURE WILL MOVE INTO THE CENTRAL PLAINS
STATES THIS AFTERNOON/TONIGHT AND SPREAD A MID DECK(ABOVE 10K
FEET) OF CLOUDS OVER THE TAF SITES. THE 28.12Z GFS/NAM BUFKIT
SOUNDINGS ARE SHOWING AN INVERSION DEVELOPING TONIGHT AND
MOISTENING UP THE NEAR SURFACE BOUNDARY LAYER. THIS MOISTURE LOOKS
OVERDONE...AS REGION WILL BE UNDER THE INFLUENCE OF SURFACE HIGH
OVER NORTHERN WISCONSIN. EXPECT VFR CONDITIONS TO PREVAIL AT BOTH
LSE/RST TAF SITES TONIGHT THROUGH THE REST OF THE TAF PERIOD.
&&
.HYDROLOGY...
ISSUED AT 311 AM CDT FRI MAR 28 2014
AREA RIVERS AND STREAMS CONTINUE TO MOSTLY RISE EARLY THIS MORNING
FROM THE RECENT RAIN. RAINFALL AMOUNTS AS MUCH AS A LITTLE OVER 1
INCH WERE OBSERVED...HIGHEST OVER THE SOUTHEAST HALF OF THE
FORECAST AREA. WITH FROZEN GROUND...MUCH OF THIS RAIN HAS TURNED
INTO RUNOFF. SO FAR THE ONLY FLOOD WARNING ISSUED AND VERIFIED WAS
ONTARIO...WHILE MOST OTHER RIVERS AND STREAMS ARE STAYING BELOW
FLOOD STAGE. EXPECTING MOST SHORT RESPONDING SITES LIKE ONTARIO TO
BEGIN FALLING SOON...WHILE LONGER RESPONDING LOCATIONS WILL CLIMB
FOR THE NEXT DAY OR SO AS RUNOFF CONTINUES TO FILTER THROUGH. SEE
THE LATEST HYDROLOGY RELATED STATEMENTS FOR MORE DETAILS.
NEXT HYDROLOGY CONCERN COMES SUNDAY THROUGH MONDAY AS A STRONG
SURGE OF WARM AIR COMES INTO THE REGION ON BREEZY SOUTH WINDS. IN
ADDITION...RAIN APPEARS LIKELY ON MONDAY. WITH PLENTY OF SNOW
STILL PRESENT ALONG/NORTH OF HIGHWAY 10...CONCERN THAT THIS SNOW
COULD RAPIDLY MELT...RESULTING IN MORE RISES ON RIVERS SUCH AS THE
TREMPEALEAU AND BLACK. WILL ISSUE AN ESF TO COVER THE POTENTIAL
FOR FLOODING. SOMEWHAT COOLER AIR FLOWING IN FOR TUESDAY AND
WEDNESDAY WILL SLOW THE MELT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...DTJ
HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
646 AM CDT FRI MAR 28 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 311 AM CDT FRI MAR 28 2014
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING ALONG THE U.S. WEST COAST INTO BRITISH COLUMBIA...A
PACIFIC SHORTWAVE OVER WYOMING...A VIGOROUS PACIFIC SHORTWAVE NEAR
DAVENPORT IA...AND A POLAR SHORTWAVE OVER LAKE WINNIPEG. THE
DAVENPORT IA SHORTWAVE...IN COMBINATION WITH PRECIPITABLE WATER
VALUES OF 0.6-0.9 INCHES / 200 PERCENT OF NORMAL / AND FRONTOGENESIS
HELPED PRODUCE PRECIPITATION ACROSS MUCH OF THE FORECAST AREA
YESTERDAY TO AROUND MIDNIGHT. MUCH OF THIS PRECIPITATION FELL AS
RAIN...WHICH WITH FROZEN GROUND HAS LED TO PLENTY OF RUNOFF AND
RISES ON AREA RIVERS AND STREAMS. SEE THE HYDROLOGY SECTION FOR MORE
INFORMATION. SOME OF THE PRECIPITATION FELL AS SNOW...MAINLY IN
NORTHWEST TO NORTH SECTIONS OF THE AREA...WITH THE MOST IN TAYLOR
COUNTY. LOW LEVEL CYCLONIC FLOW AROUND LOW PRESSURE OVER CENTRAL
LAKE MICHIGAN HAS KEPT CLOUDS IN PLACE THROUGH THE NIGHT...THOUGH
CLEARING WAS EVIDENT OVER THE NORTHWEST HALF OF MINNESOTA.
PRECIPITABLE WATER AT BIS WAS QUITE LOW WITH THE RIDGE...0.17 INCHES
AT BIS AND ABR OR 50-60 PERCENT OF NORMAL. COLDER AIR WAS ALSO
FILTERING IN...REFLECTING A CANADIAN RIDGE OF HIGH PRESSURE BUILDING
SOUTH INTO THE UPPER MIDWEST. FARTHER TO THE WEST...CLOUDS AND SOME
SCATTERED LIGHT PRECIPITATION WAS OCCURRING OVER WYOMING WITH THE
SHORTWAVE THERE.
AFTER AN ACTIVE PERIOD OF PRECIPITATION THE PAST 24 HOURS...THIS
SHORT TERM PERIOD LOOKS MUCH QUIETER. FOCUS FOR ANY POTENTIAL
PRECIPITATION WOULD BE ON THE SHORTWAVE OVER WYOMING...WHICH IS
PROGGED BY MODELS TO CROSS THE FORECAST AREA TONIGHT. HOWEVER...
THERE ARE 2 ITEMS GOING AGAINST PRECIPITATION... 1. ANOTHER
SHORTWAVE COMING OUT OF ARIZONA IS SUGGESTED TO INTENSIFY AND DEEPEN
AS IT REACHES MISSOURI TONIGHT...ROBBING THE WYOMING SHORTWAVE OF
MOISTURE. 2. THE WYOMING SHORTWAVE WILL BE HEADING INTO A DRY
AIRMASS AS SEEN ON THE BIS/ABR SOUNDINGS. MODELS CONTINUE TO DEPICT
THAT ANY PRECIPITATION WITH THE SHORTWAVE WILL DRY UP BEFORE THE
SHORTWAVE GETS TO THE FORECAST AREA...THUS STAYED WITH A DRY
FORECAST.
CLOUDS AND TEMPERATURES NOW BECOME THE MAIN CONCERNS. LOW CLOUDS
LOOK TO QUICKLY EXIT OFF TO THE EAST THIS MORNING AS THE DRIER AIR
TO OUR NORTHWEST ADVECTS IN. SCT-BKN MID AND HIGH CLOUDS WILL THEN
TRAVERSE THE AREA THIS AFTERNOON THROUGH TONIGHT AS THE WYOMING
SHORTWAVE MOVES THROUGH. 925MB TEMPS ARE PROGGED BETWEEN -2 TO -6C
AT 18Z...THOUGH MORE SUN TODAY WILL HELP TO COUNTERACT SOME OF THE
COLDER AIR. IN FACT...OVER THE SNOW FREE AREAS...TEMPERATURES MAY
EVEN END UP A LITTLE WARMER THAN YESTERDAY. ALTHOUGH SURFACE WINDS
LOOK LIGHT TONIGHT...THE CLOUDS SHOULD HELP TO HOLD READINGS UP FROM
THE MID TEENS TO MID 20S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 311 AM CDT FRI MAR 28 2014
MUCH OF THE LONG TERM PERIOD FOCUSES ON AN IMPRESSIVE LONG WAVE
TROUGH SITTING OVER THE EASTERN PACIFIC. ALL MODELS SHOW THAT A
POTENT SHORTWAVE WILL COME OUT OF THIS TROUGH AND TRACK INTO THE
FORECAST AREA FOR MONDAY. THEN THE ENTIRE TROUGH LOOKS TO COME INTO
THE WESTERN U.S. ON TUESDAY...TRACKING INTO THE CENTRAL PLAINS ON
THURSDAY.
MUCH OF FRIDAY NIGHT THROUGH SUNDAY LOOKS TO BE DOMINATED BY
BUILDING RIDGING AHEAD OF THE POTENT SHORTWAVE MARCHING ACROSS THE
WESTERN U.S.. NO CONCERNS FOR PRECIPITATION DURING THIS PERIOD AS
THE FORECAST AREA TRANSITIONS FROM UNDER DOMINANCE OF HIGH PRESSURE
TO INTO THE WARM SECTOR OF A DEEPENING SURFACE CYCLONE OVER
NORTHEAST COLORADO. TEMPERATURES AND WINDS ARE THE MAIN ISSUES.
925MB TEMPS ARE PROGGED SLIGHTLY WARMER ON SATURDAY...0 TO -
4C...WHICH WITH WHAT LOOKS TO BE PLENTY OF SUN SHOULD HELP BOOST
TEMPS INTO THE 40S...PERHAPS EVEN AROUND 50 IN SOME VALLEY
LOCATIONS. SOUTH TO SOUTHWEST WINDS REALLY PICK UP SATURDAY
NIGHT...UPWARDS OF 40-50 KT BY 12Z SUN AT 925MB...CAUSING 925-850MB
TEMPS TO REALLY CLIMB. ANTICIPATING LOWS IN THE EVENING SATURDAY
NIGHT...THEN HOLD STEADY TO SLOWLY RISE AS THE WARM AIR SURGES IN.
THE CLIMB CONTINUES THROUGH SUNDAY AS THE 925MB TEMPS CLIMB TO AS
MUCH AS 10-13C BY 00Z MONDAY. 400-250MB RH PROGS SUGGESTS PLENTY OF
SCT-BKN CIRRUS...BUT THE SUN AND WARM 925MB TEMPS SHOULD HELP PROPEL
READINGS INTO THE FIRST 60S OF THE YEAR FOR MOST LOCATIONS. MORE
SNOWPACK OVER TAYLOR/CLARK WILL HOLD READINGS BACK THERE INTO THE
50S...THOUGH THIS SNOWPACK IS GOING TO MELT FAST GIVEN THE WARM AIR
AND BREEZY CONDITIONS...YIELDING HYDRO CONCERNS. SEE HYDROLOGY
SECTION.
ATTENTION THEN TURNS TO THE POTENT SHORTWAVE HEADING INTO THE
FORECAST AREA FOR MONDAY. BOTH THE GFS AND ECMWF HAVE REALLY SLOWED
AND DEEPENED THIS SHORTWAVE AND THE ASSOCIATED SURFACE LOW OVER THE
PAST 24-48 HOURS. THIS RESULTS IN THE FORECAST AREA STAYING IN THE
WARM SECTOR LONGER AND THUS WARMER CONDITIONS ARE FORECAST FOR
SUNDAY NIGHT AND MONDAY. THERE ARE A COUPLE OF PRECIPITATION IMPACTS
TOO. FIRST...THE DEFORMATION BAND ON THE NORTHWEST SIDE OF THE LOW
NOW ONLY LOOKS TO IMPACT THE NORTHWEST HALF OF THE AREA MONDAY
AFTERNOON AND NIGHT...THOUGH IT MAY STAY ENTIRELY NORTHWEST OF THE
FORECAST AREA. SECOND...A LEAD WAVE OF RAIN RESULTING FROM
ISENTROPIC LIFT IS LOOKING LIKELY TO PROGRESS ACROSS THE FORECAST
AREA LATE SUNDAY NIGHT THROUGH EARLY MONDAY AFTERNOON. THIRD...THE
SYSTEMS COLD FRONT AND STRONG DYNAMICS ARE PROGGED TO MOVE THROUGH
MONDAY AFTERNOON AND EVENING. THERE IS A CAP TO BE OVERCOME...BUT
WITH SUCH STRONG FORCING...CANNOT RULE OUT A BAND OF SHOWERS AND
STORMS FIRING ON THE FRONT. SHOULD STORMS FORM...WHICH IS A BIG
IF...THERE IS AMPLE SHEAR TO SUPPORT SEVERE. WE WILL NEED TO KEEP AN
EYE ON INSTABILITY VERSUS CAPPING FOR MONDAY AFTERNOON.
TUESDAY INTO TUESDAY NIGHT LOOK TO BE QUIET AND MUCH COLDER...THEN
WEATHER GETS ACTIVE AGAIN FOR WEDNESDAY INTO THURSDAY AS THE REST OF
THE UPPER TROUGH LIFTS TOWARDS THE REGION. THIS TIME AROUND...WE MAY
HAVE TO DEAL WITH A WINTRY MIX SIDE DUE TO WARM/MOIST ADVECTION
ALOFT AND A FLOW OF DRY AIR AND COLD ADVECTION AT THE SURFACE.
THEN...IF THE 28.00Z ECMWF IS CORRECT...WE WILL AT LEAST CHANGE OVER
TO ALL RAIN AND PERHAPS BRING MORE THUNDERSTORMS. NEEDLESS TO
SAY...PLENTY OF UNCERTAINTY OUT THIS FAR AND THUS STAYED WITH A
MODEL CONSENSUS FOR NOW. CERTAINLY ANOTHER ITEM TO WATCH.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 646 AM CDT FRI MAR 28 2014
MVFR CONDITIONS THIS MORNING WILL GRADUALLY GIVE WAY TO VFR
CONDITIONS LATE THIS MORNING INTO THIS AFTERNOON AS SURFACE HIGH
PRESSURE BUILDS IN FROM THE NORTHERN PLAINS. PLAN ON CEILINGS IN
THE 1200 TO 2000 FT RANGE THIS MORNING...SCATTERING OUT BY LATE
MORNING AND EARLY AFTERNOON. A STORM SYSTEM IS EXPECTED TO TRACK
ACROSS THE CENTRAL PLAINS THIS AFTERNOON INTO THE OVERNIGHT HOURS
SPREADING MID TO HIGH LEVEL CLOUDS ACROSS THE TAF SITES WITH CLOUD
BASES IN THE 10 KFT TO 20 KFT RANGE.
&&
.HYDROLOGY...
ISSUED AT 311 AM CDT FRI MAR 28 2014
AREA RIVERS AND STREAMS CONTINUE TO MOSTLY RISE EARLY THIS MORNING
FROM THE RECENT RAIN. RAINFALL AMOUNTS AS MUCH AS A LITTLE OVER 1
INCH WERE OBSERVED...HIGHEST OVER THE SOUTHEAST HALF OF THE
FORECAST AREA. WITH FROZEN GROUND...MUCH OF THIS RAIN HAS TURNED
INTO RUNOFF. SO FAR THE ONLY FLOOD WARNING ISSUED AND VERIFIED WAS
ONTARIO...WHILE MOST OTHER RIVERS AND STREAMS ARE STAYING BELOW
FLOOD STAGE. EXPECTING MOST SHORT RESPONDING SITES LIKE ONTARIO TO
BEGIN FALLING SOON...WHILE LONGER RESPONDING LOCATIONS WILL CLIMB
FOR THE NEXT DAY OR SO AS RUNOFF CONTINUES TO FILTER THROUGH. SEE
THE LATEST HYDROLOGY RELATED STATEMENTS FOR MORE DETAILS.
NEXT HYDROLOGY CONCERN COMES SUNDAY THROUGH MONDAY AS A STRONG
SURGE OF WARM AIR COMES INTO THE REGION ON BREEZY SOUTH WINDS. IN
ADDITION...RAIN APPEARS LIKELY ON MONDAY. WITH PLENTY OF SNOW
STILL PRESENT ALONG/NORTH OF HIGHWAY 10...CONCERN THAT THIS SNOW
COULD RAPIDLY MELT...RESULTING IN MORE RISES ON RIVERS SUCH AS THE
TREMPEALEAU AND BLACK. WILL ISSUE AN ESF TO COVER THE POTENTIAL
FOR FLOODING. SOMEWHAT COOLER AIR FLOWING IN FOR TUESDAY AND
WEDNESDAY WILL SLOW THE MELT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...WETENKAMP
HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
311 AM CDT FRI MAR 28 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 311 AM CDT FRI MAR 28 2014
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING ALONG THE U.S. WEST COAST INTO BRITISH COLUMBIA...A
PACIFIC SHORTWAVE OVER WYOMING...A VIGOROUS PACIFIC SHORTWAVE NEAR
DAVENPORT IA...AND A POLAR SHORTWAVE OVER LAKE WINNIPEG. THE
DAVENPORT IA SHORTWAVE...IN COMBINATION WITH PRECIPITABLE WATER
VALUES OF 0.6-0.9 INCHES / 200 PERCENT OF NORMAL / AND FRONTOGENESIS
HELPED PRODUCE PRECIPITATION ACROSS MUCH OF THE FORECAST AREA
YESTERDAY TO AROUND MIDNIGHT. MUCH OF THIS PRECIPITATION FELL AS
RAIN...WHICH WITH FROZEN GROUND HAS LED TO PLENTY OF RUNOFF AND
RISES ON AREA RIVERS AND STREAMS. SEE THE HYDROLOGY SECTION FOR MORE
INFORMATION. SOME OF THE PRECIPITATION FELL AS SNOW...MAINLY IN
NORTHWEST TO NORTH SECTIONS OF THE AREA...WITH THE MOST IN TAYLOR
COUNTY. LOW LEVEL CYCLONIC FLOW AROUND LOW PRESSURE OVER CENTRAL
LAKE MICHIGAN HAS KEPT CLOUDS IN PLACE THROUGH THE NIGHT...THOUGH
CLEARING WAS EVIDENT OVER THE NORTHWEST HALF OF MINNESOTA.
PRECIPITABLE WATER AT BIS WAS QUITE LOW WITH THE RIDGE...0.17 INCHES
AT BIS AND ABR OR 50-60 PERCENT OF NORMAL. COLDER AIR WAS ALSO
FILTERING IN...REFLECTING A CANADIAN RIDGE OF HIGH PRESSURE BUILDING
SOUTH INTO THE UPPER MIDWEST. FARTHER TO THE WEST...CLOUDS AND SOME
SCATTERED LIGHT PRECIPITATION WAS OCCURRING OVER WYOMING WITH THE
SHORTWAVE THERE.
AFTER AN ACTIVE PERIOD OF PRECIPITATION THE PAST 24 HOURS...THIS
SHORT TERM PERIOD LOOKS MUCH QUIETER. FOCUS FOR ANY POTENTIAL
PRECIPITATION WOULD BE ON THE SHORTWAVE OVER WYOMING...WHICH IS
PROGGED BY MODELS TO CROSS THE FORECAST AREA TONIGHT. HOWEVER...
THERE ARE 2 ITEMS GOING AGAINST PRECIPITATION... 1. ANOTHER
SHORTWAVE COMING OUT OF ARIZONA IS SUGGESTED TO INTENSIFY AND DEEPEN
AS IT REACHES MISSOURI TONIGHT...ROBBING THE WYOMING SHORTWAVE OF
MOISTURE. 2. THE WYOMING SHORTWAVE WILL BE HEADING INTO A DRY
AIRMASS AS SEEN ON THE BIS/ABR SOUNDINGS. MODELS CONTINUE TO DEPICT
THAT ANY PRECIPITATION WITH THE SHORTWAVE WILL DRY UP BEFORE THE
SHORTWAVE GETS TO THE FORECAST AREA...THUS STAYED WITH A DRY
FORECAST.
CLOUDS AND TEMPERATURES NOW BECOME THE MAIN CONCERNS. LOW CLOUDS
LOOK TO QUICKLY EXIT OFF TO THE EAST THIS MORNING AS THE DRIER AIR
TO OUR NORTHWEST ADVECTS IN. SCT-BKN MID AND HIGH CLOUDS WILL THEN
TRAVERSE THE AREA THIS AFTERNOON THROUGH TONIGHT AS THE WYOMING
SHORTWAVE MOVES THROUGH. 925MB TEMPS ARE PROGGED BETWEEN -2 TO -6C
AT 18Z...THOUGH MORE SUN TODAY WILL HELP TO COUNTERACT SOME OF THE
COLDER AIR. IN FACT...OVER THE SNOW FREE AREAS...TEMPERATURES MAY
EVEN END UP A LITTLE WARMER THAN YESTERDAY. ALTHOUGH SURFACE WINDS
LOOK LIGHT TONIGHT...THE CLOUDS SHOULD HELP TO HOLD READINGS UP FROM
THE MID TEENS TO MID 20S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 311 AM CDT FRI MAR 28 2014
MUCH OF THE LONG TERM PERIOD FOCUSES ON AN IMPRESSIVE LONG WAVE
TROUGH SITTING OVER THE EASTERN PACIFIC. ALL MODELS SHOW THAT A
POTENT SHORTWAVE WILL COME OUT OF THIS TROUGH AND TRACK INTO THE
FORECAST AREA FOR MONDAY. THEN THE ENTIRE TROUGH LOOKS TO COME INTO
THE WESTERN U.S. ON TUESDAY...TRACKING INTO THE CENTRAL PLAINS ON
THURSDAY.
MUCH OF FRIDAY NIGHT THROUGH SUNDAY LOOKS TO BE DOMINATED BY
BUILDING RIDGING AHEAD OF THE POTENT SHORTWAVE MARCHING ACROSS THE
WESTERN U.S.. NO CONCERNS FOR PRECIPITATION DURING THIS PERIOD AS
THE FORECAST AREA TRANSITIONS FROM UNDER DOMINANCE OF HIGH PRESSURE
TO INTO THE WARM SECTOR OF A DEEPENING SURFACE CYCLONE OVER
NORTHEAST COLORADO. TEMPERATURES AND WINDS ARE THE MAIN ISSUES.
925MB TEMPS ARE PROGGED SLIGHTLY WARMER ON SATURDAY...0 TO -
4C...WHICH WITH WHAT LOOKS TO BE PLENTY OF SUN SHOULD HELP BOOST
TEMPS INTO THE 40S...PERHAPS EVEN AROUND 50 IN SOME VALLEY
LOCATIONS. SOUTH TO SOUTHWEST WINDS REALLY PICK UP SATURDAY
NIGHT...UPWARDS OF 40-50 KT BY 12Z SUN AT 925MB...CAUSING 925-850MB
TEMPS TO REALLY CLIMB. ANTICIPATING LOWS IN THE EVENING SATURDAY
NIGHT...THEN HOLD STEADY TO SLOWLY RISE AS THE WARM AIR SURGES IN.
THE CLIMB CONTINUES THROUGH SUNDAY AS THE 925MB TEMPS CLIMB TO AS
MUCH AS 10-13C BY 00Z MONDAY. 400-250MB RH PROGS SUGGESTS PLENTY OF
SCT-BKN CIRRUS...BUT THE SUN AND WARM 925MB TEMPS SHOULD HELP PROPEL
READINGS INTO THE FIRST 60S OF THE YEAR FOR MOST LOCATIONS. MORE
SNOWPACK OVER TAYLOR/CLARK WILL HOLD READINGS BACK THERE INTO THE
50S...THOUGH THIS SNOWPACK IS GOING TO MELT FAST GIVEN THE WARM AIR
AND BREEZY CONDITIONS...YIELDING HYDRO CONCERNS. SEE HYDROLOGY
SECTION.
ATTENTION THEN TURNS TO THE POTENT SHORTWAVE HEADING INTO THE
FORECAST AREA FOR MONDAY. BOTH THE GFS AND ECMWF HAVE REALLY SLOWED
AND DEEPENED THIS SHORTWAVE AND THE ASSOCIATED SURFACE LOW OVER THE
PAST 24-48 HOURS. THIS RESULTS IN THE FORECAST AREA STAYING IN THE
WARM SECTOR LONGER AND THUS WARMER CONDITIONS ARE FORECAST FOR
SUNDAY NIGHT AND MONDAY. THERE ARE A COUPLE OF PRECIPITATION IMPACTS
TOO. FIRST...THE DEFORMATION BAND ON THE NORTHWEST SIDE OF THE LOW
NOW ONLY LOOKS TO IMPACT THE NORTHWEST HALF OF THE AREA MONDAY
AFTERNOON AND NIGHT...THOUGH IT MAY STAY ENTIRELY NORTHWEST OF THE
FORECAST AREA. SECOND...A LEAD WAVE OF RAIN RESULTING FROM
ISENTROPIC LIFT IS LOOKING LIKELY TO PROGRESS ACROSS THE FORECAST
AREA LATE SUNDAY NIGHT THROUGH EARLY MONDAY AFTERNOON. THIRD...THE
SYSTEMS COLD FRONT AND STRONG DYNAMICS ARE PROGGED TO MOVE THROUGH
MONDAY AFTERNOON AND EVENING. THERE IS A CAP TO BE OVERCOME...BUT
WITH SUCH STRONG FORCING...CANNOT RULE OUT A BAND OF SHOWERS AND
STORMS FIRING ON THE FRONT. SHOULD STORMS FORM...WHICH IS A BIG
IF...THERE IS AMPLE SHEAR TO SUPPORT SEVERE. WE WILL NEED TO KEEP AN
EYE ON INSTABILITY VERSUS CAPPING FOR MONDAY AFTERNOON.
TUESDAY INTO TUESDAY NIGHT LOOK TO BE QUIET AND MUCH COLDER...THEN
WEATHER GETS ACTIVE AGAIN FOR WEDNESDAY INTO THURSDAY AS THE REST OF
THE UPPER TROUGH LIFTS TOWARDS THE REGION. THIS TIME AROUND...WE MAY
HAVE TO DEAL WITH A WINTRY MIX SIDE DUE TO WARM/MOIST ADVECTION
ALOFT AND A FLOW OF DRY AIR AND COLD ADVECTION AT THE SURFACE.
THEN...IF THE 28.00Z ECMWF IS CORRECT...WE WILL AT LEAST CHANGE OVER
TO ALL RAIN AND PERHAPS BRING MORE THUNDERSTORMS. NEEDLESS TO
SAY...PLENTY OF UNCERTAINTY OUT THIS FAR AND THUS STAYED WITH A
MODEL CONSENSUS FOR NOW. CERTAINLY ANOTHER ITEM TO WATCH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1159 PM CDT THU MAR 27 2014
MAIN AREA OF PRECIPITATION CONTINUES TO PROGRESS STEADILY EASTWARD
AND WILL BE PAST KLSE BY 06Z. HOWEVER...THE LOW CLOUDS AND IFR
CEILINGS WILL CONTINUE THROUGH MUCH OF THE NIGHT. OBSERVATIONS
INDICATE CEILINGS OF A THOUSAND FEET OR LESS EXTEND BACK INTO
WESTERN IOWA WITH MVFR CEILINGS TO THE MISSOURI RIVER. THE 28.00Z
NAM CONTINUES TO HAVE A GOOD HANDLE ON THIS MOISTURE AND SHOWS
THESE CLOUDS REMAINING THROUGH THE NIGHT AND DISSIPATING UNTIL MID
MORNING. GRADIENT IS TIGHT ENOUGH BEHIND THE PASSING SURFACE LOW
FOR SOME GUSTY NORTH TO NORTHWEST WINDS THROUGH THE NIGHT AS WELL.
THESE WILL ALSO SETTLE DOWN BY MID MORNING. SHORT WAVE TROUGH
COMING ACROSS THE NORTHERN ROCKIES IS EXPECTED TO AMPLIFY AND MOVE
SOUTH OF THE REGION FRIDAY. THIS SHOULD STILL PASS CLOSE ENOUGH TO
PRODUCE MID LEVEL CLOUDS ACROSS THE REGION WITH A VFR CEILING.
HIGH PRESSURE WILL DOMINATE AT THE SURFACE WITH ANY PRECIPITATION
FROM THE WAVE STAYING WELL TO THE SOUTH OF THE AREA.
&&
.HYDROLOGY...
ISSUED AT 311 AM CDT FRI MAR 28 2014
AREA RIVERS AND STREAMS CONTINUE TO MOSTLY RISE EARLY THIS MORNING
FROM THE RECENT RAIN. RAINFALL AMOUNTS AS MUCH AS A LITTLE OVER 1
INCH WERE OBSERVED...HIGHEST OVER THE SOUTHEAST HALF OF THE
FORECAST AREA. WITH FROZEN GROUND...MUCH OF THIS RAIN HAS TURNED
INTO RUNOFF. SO FAR THE ONLY FLOOD WARNING ISSUED AND VERIFIED WAS
ONTARIO...WHILE MOST OTHER RIVERS AND STREAMS ARE STAYING BELOW
FLOOD STAGE. EXPECTING MOST SHORT RESPONDING SITES LIKE ONTARIO TO
BEGIN FALLING SOON...WHILE LONGER RESPONDING LOCATIONS WILL CLIMB
FOR THE NEXT DAY OR SO AS RUNOFF CONTINUES TO FILTER THROUGH. SEE
THE LATEST HYDROLOGY RELATED STATEMENTS FOR MORE DETAILS.
NEXT HYDROLOGY CONCERN COMES SUNDAY THROUGH MONDAY AS A STRONG
SURGE OF WARM AIR COMES INTO THE REGION ON BREEZY SOUTH WINDS. IN
ADDITION...RAIN APPEARS LIKELY ON MONDAY. WITH PLENTY OF SNOW
STILL PRESENT ALONG/NORTH OF HIGHWAY 10...CONCERN THAT THIS SNOW
COULD RAPIDLY MELT...RESULTING IN MORE RISES ON RIVERS SUCH AS THE
TREMPEALEAU AND BLACK. WILL ISSUE AN ESF TO COVER THE POTENTIAL
FOR FLOODING. SOMEWHAT COOLER AIR FLOWING IN FOR TUESDAY AND
WEDNESDAY WILL SLOW THE MELT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...04
HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1159 PM CDT THU MAR 27 2014
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 355 PM CDT THU MAR 27 2014
AT 3 PM...A 992 MB SURFACE LOW WAS CENTERED OF THE SOUTHWEST
CORNER OF IOWA. THE LATEST MSAS SHOWS 3 HOUR HEIGHT FALLS OF 3
MILLIBARS ACROSS EASTERN IOWA...SOUTHERN WISCONSIN...AND NORTHERN
ILLINOIS. AS RESULT...EXPECT THE LOW TO CONTINUE TO TRACK
NORTHEAST ACROSS IOWA LATE THIS AFTERNOON AND EARLY EARLY EVENING.
MODERATE TO STRONG 850 MB MOISTURE TRANSPORT MOVES INTO NORTHEAST
IOWA...AND SOUTHWEST AND CENTRAL WISCONSIN BETWEEN 27.21Z AND
28.03Z. DUE TO THIS...INCREASED THE PRECIPITATION TOTALS INTO THE
0.35 TO 0.75 INCH RANGE.
IN ADDITION TO THIS...THE MOST UNSTABLE CAPES CLIMB UP TO
300 J/KG ACROSS PARTS OF NORTHEAST IOWA...SOUTHEAST
MINNESOTA...AND SOUTHWEST AND CENTRAL WISCONSIN. THERE HAS ALREADY
BEEN A FEW ISOLATED REPORTS OF LIGHTNING ALONG AND SOUTH OF
INTERSTATE 90 THIS AFTERNOON. WITH THE CAPES A BIT FURTHER NORTH
AND WEST...EXPANDED THE CHANCE OF THUNDERSTORMS MORE INTO
NORTHEAST IOWA...SOUTHEAST MINNESOTA...AND AS FAR AS NORTH OF
INTERSTATE 90 CORRIDOR THROUGH 28.03Z. WITH THE 0-3 KM AND 0-6 KM
SHEAR LESS THAN 30 KNOTS...NOT EXPECTING ANYTHING SEVERE.
MEANWHILE ACROSS SOUTHEAST MINNESOTA AND NORTH CENTRAL
WISCONSIN...COLD AIR ADVECTION DEVELOPS ACROSS SOUTHEAST
MINNESOTA AND NORTH CENTRAL WISCONSIN. THE NAM IS THE STRONGEST
AND FASTEST WITH THIS COLD AIR ADVECTION. AS A RESULT...IT
PRODUCES MUCH MORE SNOW ACROSS SOUTHEAST MINNESOTA /UP TO 2.5
INCHES IN COBB/ TONIGHT. HOWEVER THE 18Z AMDAR SOUNDINGS SHOW THAT
IT IS A BIT TOO COLD AND MUCH CLOSER TO THE RAP AND GFS. AS A
RESULT...TRENDED THE SWITCH OVER FROM RAIN TO SNOW A BIT LATER
THAN PREVIOUSLY FORECAST. IT LOOKS LIKE THIS WILL OCCUR...NORTH
OF INTERSTATE 94 BETWEEN 27.21Z AND 28.00Z...WEST OF MISSISSIPPI
RIVER BETWEEN 28.00Z AND 28.03Z...AND ACROSS THE REMAINDER OF THE
AREA BETWEEN 28.04Z AND 28.08Z. SOUTHEAST MINNESOTA WILL SEE UP TO
AN INCH...AND AROUND 3 INCHES NORTH OF WISCONSIN 29 IN NORTH
CENTRAL WISCONSIN. ELSEWHERE VERY LITTLE...IF ANY...SNOW IS
EXPECTED.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 355 PM CDT THU MAR 27 2014
ON SUNDAY...A TIGHT PRESSURE GRADIENT DEVELOPS ALONG AND SOUTH OF
THE INTERSTATE 90 CORRIDOR AHEAD OF A DEEPENING LOW OVER THE
NORTHERN PLAINS. THIS TIGHT PRESSURE GRADIENT WILL ALLOW THE
SUSTAINED SOUTH WINDS TO CLIMB INTO THE 15 TO 25 KNOT RANGE AND
THE WINDS WILL GUST UP TO 35 MPH. AT THE SAME...THE 850 MB
TEMPERATURES WILL CLIMB INTO THE 10 TO 14C RANGE ACROSS THE
SOUTHERN HALF OF THE FORECAST AREA. BUFKIT SOUNDING SHOW THAT WE
WILL NOT QUITE MIX UP TO THIS LEVEL...BUT WE WILL MIX UP INTO THE
900 TO 875 MB LAYER...AND THIS WILL ALLOW TEMPERATURES TO CLIMB
INTO THE LOW AND MID 50S NORTH OF INTERSTATE 94...AND AROUND 60
ACROSS THE REMAINDER OF THE AREA.
FROM SUNDAY NIGHT INTO MONDAY NIGHT...THE MODELS CONTINUE TO SHOW
THAT A NEGATIVELY TILTED SHORT WAVE TROUGH WILL MOVE THROUGH THE
FORECAST AREA. TEMPERATURES ALOFT ARE WARM ENOUGH THAT MUCH OF THE
PRECIPITATION WILL FALL MAINLY IN THE FORM OF RAIN. WHILE THE
0-6 KM SHEAR ARE GREATER THAN 35 KNOTS...THERE IS VERY LITTLE
CAPE ACROSS THE REGION...SO THERE IS NOT ANY THREAT FOR ANY SEVERE
WEATHER.
BEYOND THIS TIME PERIOD...THE 27.00Z MODELS HAVE DIFFERING
OPINIONS ON HOW FAR NORTH A LOW WILL TRACK THROUGH NORTHERN AND
MID MISSISSIPPI RIVER VALLEY. THE ECMWF IS MUCH FURTHER NORTH THAN
THE GFS. WITH SUCH DIVERSE SOLUTIONS...JUST STAYED WITH THE MODEL
CONSENSUS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1159 PM CDT THU MAR 27 2014
MAIN AREA OF PRECIPITATION CONTINUES TO PROGRESS STEADILY EASTWARD
AND WILL BE PAST KLSE BY 06Z. HOWEVER...THE LOW CLOUDS AND IFR
CEILINGS WILL CONTINUE THROUGH MUCH OF THE NIGHT. OBSERVATIONS
INDICATE CEILINGS OF A THOUSAND FEET OR LESS EXTEND BACK INTO
WESTERN IOWA WITH MVFR CEILINGS TO THE MISSOURI RIVER. THE 28.00Z
NAM CONTINUES TO HAVE A GOOD HANDLE ON THIS MOISTURE AND SHOWS
THESE CLOUDS REMAINING THROUGH THE NIGHT AND DISSIPATING UNTIL MID
MORNING. GRADIENT IS TIGHT ENOUGH BEHIND THE PASSING SURFACE LOW
FOR SOME GUSTY NORTH TO NORTHWEST WINDS THROUGH THE NIGHT AS WELL.
THESE WILL ALSO SETTLE DOWN BY MID MORNING. SHORT WAVE TROUGH
COMING ACROSS THE NORTHERN ROCKIES IS EXPECTED TO AMPLIFY AND MOVE
SOUTH OF THE REGION FRIDAY. THIS SHOULD STILL PASS CLOSE ENOUGH TO
PRODUCE MID LEVEL CLOUDS ACROSS THE REGION WITH A VFR CEILING.
HIGH PRESSURE WILL DOMINATE AT THE SURFACE WITH ANY PRECIPITATION
FROM THE WAVE STAYING WELL TO THE SOUTH OF THE AREA.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...04
AREA FORECAST DISCUSSION...UPDATED
NWS RENO NV
922 PM PDT SAT MAR 29 2014
.UPDATE...
RADAR TRENDS OVER THE LAST COUPLE HOURS ARE SHOWING MAIN PRECIP
BAND SLIDING SLOWLY TO THE SOUTH. BASED ON LATEST HRRR GUIDANCE
WHICH HAS A REASONABLE GRASP OF THE SITUATION, SNOW RATES SHOULD
DIMINISH FOR THE TAHOE BASIN AND NORTH OF I-80 AFTER ABOUT 6-7Z,
WITH HEAVY SNOWS CONTINUING IN MONO CO UNTIL ABOUT DAYBREAK
SUNDAY. THIS IS ALL CONSISTENT WITH ONGOING FORECAST AND WARNINGS,
SO NO CHANGES PLANNED. I DID CONSIDER DROPPING WINTER WEATHER
ADVISORY FOR CAZ071 (NORTH OF I-80) BUT SNOW SHOWERS WILL LIKELY
CONTINUE INTO THE OVERNIGHT HOURS BASED ON GUIDANCE AND RADAR
TRENDS. THOSE COULD PUT DOWN SOME QUICK ACCUMULATIONS AND IMPACT
ROADWAYS.
SPILLOVER INTO THE RENO/CARSON CITY AREAS HAS BEEN A STRUGGLE
THUS FAR, BUT WE`RE NOW GETTING LIGHT TO MODERATE RAIN/SNOW
SHOWERS INCREASING IN COVERAGE. THIS SHOULD CONTINUE INTO THE
OVERNIGHT HOURS. LOWERING SNOW LEVELS MAY YIELD LIGHT
ACCUMULATIONS IN THE FOOTHILL AREAS AT/ABOVE 5000 FT TONIGHT. CS
&&
.PREVIOUS DISCUSSION... /ISSUED 308 PM PDT SAT MAR 29 2014/
SYNOPSIS...
RAIN AND SNOW WILL CONTINUE THROUGH TONIGHT AS A LATE SEASON
WINTER STORM MOVES ACROSS THE SIERRA. A COLDER STORM SYSTEM WILL
IMPACT THE REGION MONDAY AND TUESDAY WITH LIGHT SNOW POSSIBLE IN
LOWER ELEVATIONS. BELOW NORMAL TEMPERATURES ARE EXPECTED THROUGH
MUCH OF THE UPCOMING WEEK, WITH ANOTHER CHANCE OF RAIN AND SNOW
SHOWERS THURSDAY AND FRIDAY.
SHORT TERM...
PRECIPITATION CONTINUES TO INTENSIFY NEAR AND WEST OF THE SIERRA
CREST AS MAIN TROUGH APPROACHES THE CALIFORNIA COAST. UPPER LEVEL
JET WILL ALSO MOVE ONSHORE AND ENHANCE THE MOISTURE BAND. SNOW
LEVELS EAST OF THE SIERRA CREST NEAR TAHOE HAVE REMAINED NEAR
6500-7000 FEET BUT SHOULD DROP TO LAKE LEVEL BEFORE 5 PM. SNOWFALL
RATES OF 1-2 INCHES PER HOUR ARE LIKELY TO PERSIST A PERIOD OF 6-8
HOURS, AND TRAVEL IMPACTS WILL INCREASE THIS EVENING AS SNOW
BEGINS ACCUMULATING ON PAVED SURFACES. THEREFORE THE WARNING WILL
REMAIN IN PLACE. FARTHER NORTH INTO LASSEN COUNTY, ALTHOUGH SOME
SNOW HAS ALREADY ACCUMULATED ABOVE 5500 FEET, THE HEAVIER SNOW IS
ALSO EXPECTED TO END SOONER, SO THE ADVISORY SHOULD BE SUFFICIENT.
LOCALIZED SNOW SHOWER BANDS MAY CONTINUE LATER TONIGHT, DEPENDING
ON HOW MUCH CONVECTIVE ACTIVITY DEVELOPS IN NORTH CENTRAL CA
DURING THE NEXT FEW HOURS.
FOR MONO COUNTY, SNOW WILL INCREASE THIS EVENING, SPREADING
SOUTHWARD ALONG THE SIERRA AND PROBABLY REACHING THE MAMMOTH
LAKES VICINITY BY 8 PM. BEFORE THE SNOW ARRIVES, WINDY CONDITIONS
WILL CONTINUE, SO THE ADVISORY WILL BE EXTENDED FOR A FEW MORE
HOURS. SINCE ALL OF THE SNOW WILL FALL IN A COMPRESSED TIME
PERIOD AND THE BAND WILL BEGIN TO WEAKEN LATE TONIGHT, SNOW TOTALS
NEAR THE CREST MAY TOP OUT CLOSER TO 16 INCHES INSTEAD OF THE
ORIGINAL 20 INCH PROJECTION. HOWEVER, IMPACTS WILL STILL BE
SUFFICIENT TO KEEP THE WARNING IN PLACE TONIGHT.
FOR WESTERN NV, THE RAIN SHADOW HAS PERSISTED SO FAR THIS
AFTERNOON. HOWEVER, THE LAST FEW RUNS OF THE HRRR MODEL HAVE
INDICATED RAPID SPILLOVER INTO THE RENO-CARSON VICINITY BETWEEN 4
AND 5 PM, WITH UP TO 6 HOURS OF NEARLY STEADY RAIN THROUGH THIS
EVENING. IF THIS OCCURS, RAINFALL COULD STILL ADD UP TO BETWEEN
0.25 AND 0.50 INCH, WITH LOCALLY HIGHER AMOUNTS IN FOOTHILL
LOCATIONS. FOR AREAS SOUTH OF HIGHWAY 50, THE MAJORITY OF THE RAIN
WILL FALL DURING THE LATE EVENING AND OVERNIGHT HOURS. THE PRECIP
COULD END AS SNOW BELOW 5000 FEET, BUT LITTLE OR NO SNOW
ACCUMULATION IS EXPECTED IN VALLEYS. ABOVE 5000 FEET, A COUPLE
INCHES MAY ACCUMULATE, BUT SOME LOCALLY HIGHER AMOUNTS MAY FALL IN
DOUGLAS COUNTY AS THE COLD AIR ARRIVES IN CONJUNCTION WITH THE
ONGOING HEAVIER PRECIP BAND. THIS OCCURRED WITH ONE OF THE STORMS
EARLIER THIS SEASON SO THIS WOULD NEED TO BE MONITORED LATER
TONIGHT.
ALL GUIDANCE IS IN AGREEMENT FOR A RAPID DISSIPATION OF THE RAIN
AND SNOW BY EARLY SUNDAY MORNING. FOR SUNDAY, A FEW SHOWERS MAY
LINGER NEAR THE SIERRA AND IN WEST CENTRAL NV EAST OF HIGHWAY 95,
OTHERWISE MOSTLY CLOUDY AND DRY CONDITIONS WILL PREVAIL WITH
MODERATE WEST WINDS GUSTING TO 20-30 MPH IN THE AFTERNOON. MJD
A COLDER LOW PRESSURE WILL DROP ALONG THE WEST COAST EARLY NEXT
WEEK, BRINGING ADDITIONAL PRECIPITATION TO THE SIERRA AND WESTERN
NEVADA. THIS LOW WILL BRING VERY COLD AIR DOWN FROM THE GULF OF
ALASKA WITH 700MB NEAR -10C. SNOW LEVELS WILL FALL TO MOST VALLEY
FLOORS BY MONDAY NIGHT AND INTO TUESDAY MORNING.
THAT BEING SAID, THE LATEST MODEL RUNS OF THE GFS AND ECMWF HAVE
BACKED OFF ON PRECIPITATION AMOUNTS IN WESTERN NEVADA, LEADING TO
CONTINUED UNCERTAINTY AND LOW FORECASTER CONFIDENCE. THIS IS MAINLY
BECAUSE THE LOW IS TRYING TO SPLIT OFF TO THE SOUTH AND DRIVE THE
JET AND DYNAMICS WELL INTO SOUTHERN CA.
THE HIGHEST CHANCES FOR SNOW WILL REMAIN IN THE SIERRA LATE MONDAY
AS THE FIRST SHORTWAVE MOVES THROUGH NORTHERN CA. THE 500MB
SHORTWAVE LOOKS TO BECOME NEGATIVELY TILTED, WHICH IS IS NOT
NECESSARILY GOOD FOR SPILLOVER. BUT, WE SHOULD BE UNSTABLE ENOUGH
FOR SOME LIGHT SPILLOVER IF THE JET REMAINS SOUTH OF MONO COUNTY.
BY TUESDAY, LOW PRESSURE REMAINS OVER THE REGION WITH CONVECTIVE
SHOWERS DEVELOPING UNDER THE COLD POOL. INSTABILITY LOOKS FAIRLY
STRONG DUE TO THE INCREASED SOLAR HEATING. WE WILL NEED TO KEEP A
CLOSE EYE, BECAUSE A SURFACE LOW DEVELOPING OVER SOUTHERN NEVADA MAY
CREATE SOME LOW-LEVEL FORCING THAT COULD INCREASE PRECIPITATION
RATES IN THE EASTERN SIERRA AND WESTERN NEVADA. HOON
LONG TERM...WEDNESDAY THROUGH SATURDAY...
FORECAST REMAINS UNCERTAIN FOR THE SYSTEM AT THE END OF NEXT WEEK.
DETERMINISTIC SOLUTIONS HAVE LARGELY DIVERGED WITH THE GFS
PRESENTING A SPLIT SYSTEM WILL VERY LITTLE PRECIPITATION; THE EC
SHOWS A MORE CONSOLIDATED FRONT WITH LOW PRESSURE IN CENTRAL OREGON
AND DECENT PRECIP ALONG THE SIERRA. THEREFORE, VERY FEW ADJUSTMENTS
TO THE EXISTING FORECAST FAVORING A BLENDED APPROACH WITH 30-40%
CHANCE OF PRECIP ALONG THE SIERRA FROM THURSDAY INTO SATURDAY.
TEMPERATURES CONTINUE TO LOOK AROUND TO SLIGHTLY COOLER THAN
SEASONAL AVERAGES WITH MODEST COLD AIR ALOFT AT 700MB AND AMPLE
CLOUD COVER. HOPEFULLY SOLUTIONS WILL BEGIN TO CONVERGE OVER THE
NEXT DAY OR SO TO ALLOW FOR HIGHER DETAILS. BOYD
AVIATION...
A CHANGEOVER TO SNOW IS EXPECTED BY 00Z AROUND THE TAHOE BASIN,
WITH ABOUT 6-8 HOURS OF CIGS/VSBY BELOW LANDING MINIMUMS AT
KTVL/KTRK THIS EVENING AND INTO THE LATE NIGHT. FOR KMMH, THE
WORST CONDITIONS ARE LIKELY FROM 03Z-12Z FROM THIS SAME SNOW BAND.
CONDITIONS WILL IMPROVE SUNDAY MORNING ALTHOUGH SOME MVFR CIGS
COULD LINGER THROUGH MUCH OF THE DAY AS RESIDUAL MOISTURE REMAINS
IN PLACE.
FOR WESTERN NV INCLUDING KRNO-KCXP, RAIN WILL INCREASE AROUND 00Z,
PRODUCING MVFR CIGS/VSBY AT TIMES FOR 4-6 HOURS THIS EVENING. THIS
PRECIP MAY BRIEFLY END AS SNOW, BUT LITTLE OR NO SNOW ACCUMULATION
IS EXPECTED ON RUNWAYS. VFR CONDITIONS ARE EXPECTED SUNDAY
ALTHOUGH SOME MOUNTAIN OBSCURATIONS WILL REMAIN POSSIBLE DUE TO
RESIDUAL CLOUD COVER. MJD
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...WINTER STORM WARNING UNTIL 5 AM PDT SUNDAY NVZ002.
CA...WINTER WEATHER ADVISORY UNTIL 5 AM PDT SUNDAY ABOVE 5500 FEET
FOR CAZ071.
WINTER STORM WARNING UNTIL 5 AM PDT SUNDAY CAZ073.
WINTER STORM WARNING UNTIL 5 AM PDT SUNDAY CAZ072.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS NEW YORK NY
219 AM EDT SUN MAR 30 2014
.SYNOPSIS...
LOW PRESSURE OVER THE MID ATLANTIC STATES MOVES VERY SLOWLY EAST
THIS MORNING AS A WARM FRONT WORKS ONSHORE ACROSS LONG ISLAND.
THE LOW EMERGES OFF THE MID ATLANTIC AFTER DAYBREAK AND THEN
TRACKS VERY SLOWLY TO THE EAST THROUGH MONDAY. THEREAFTER...HIGH
PRESSURE BUILDS INTO THE AREA THROUGH TUE AS A WEAK COLD FRONT
APPROACHES FROM THE WEST. THIS FRONT WILL MOVE THROUGH THE AREA
TUESDAY NIGHT FOLLOWED BY HIGH PRESSURE NOSING IN FROM THE NORTH
INTO THURSDAY. A FRONTAL SYSTEM IS EXPECTED TO IMPACT THE AREA AT
THE END OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
A STRONG LOW-LEVEL JET INTERSECTING A COASTAL FRONT AND FALLING
HEIGHTS ALOFT RESULTING IN CONVECTION WITH SHOWERS AND EVEN AN
ISOLATED THUNDERSTORMS. BEST LIFT EAST OF NYC WITH THE POTENTIAL
FOR ANOTHER HALF INCH TO INCH OF RAINFALL ACROSS LI AND CT. THIS
WILL BE ON TOP OF THE TWO INCHES MOST LOCATIONS HAVE ALREADY
RECEIVED. LATEST HRRR INDICATES CONVECTION JUST EAST OF THE
DELMARVA AND NJ WORKS NORTH OVER THE NEXT SEVERAL HOURS.
SEVERAL RIVER LOCATIONS ACROSS NE NJ ARE AT OR JUST OVER BANK
FULL. THIS IS BEING HANDLED WITH URBAN AND SMALL STREAM FLOOD
ADVISORIES. WILL HAVE TO WATCH CONVECTION ACROSS EASTERN VA/MD AS
IT WORK NORTH...BUT FOR THE TIME THERE WILL BE A BREAK WHICH
SHOULD ALLOW LEVELS TO CREST AND BEGIN FALL.
FLOOD WATCH REMAINS IN EFFECT.
LOWS FOR TONIGHT WERE A BLEND OF NAM12...MET...AND MAV GUIDANCE
AND INCREASED BY TWO DEGREES...WITHOUT MUCH DIURNAL TEMPERATURE
RANGE ANTICIPATED...RANGING FROM THE UPPER 30S TO MID 40S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM MONDAY/...
LIKELY POPS CONTINUE DURING SUN MORNING AS LULL IN THE PCPN IS
EXPECTED UNTIL THE DEFORMATION BAND MOVES INTO THE AREA. OCNL
RAIN IS EXPECTED TO RETURN WITH A COASTAL FRONT DRAPED ACROSS THE
REGION WITH PERHAPS SOME FRONTOGENETICAL FORCING COMING INTO PLAY
DURING THE MID TO LATE MORNING HOURS.
AS THE SURFACE LOW ALONG WITH THE UPPER LEVEL LOW SLOWLY TRACKS
TO SOUTH OF LONG ISLAND THE AREA WILL GET MORE OF A NORTHERLY
SURFACE FLOW...WITH A GRADUAL DECREASE IN PRECIPITABLE WATER
THROUGHOUT THE DAY. MODELS CONVEY A DECREASE TO AROUND 1 INCH
PRECIPITABLE WATER BY EARLY AFTERNOON AND THEN TOWARDS 0.7-0.8
INCH BY SUNDAY EVENING. MID LEVELS DRY...ALTHOUGH DEPTH OF
SATURATED LAYER APPEARS TO BE SUFFICIENT ENOUGH FOR LIGHT RAIN
AS OPPOSED TO DZ UNTIL LATE AFTN. HIGHS WERE TAKEN FROM THE
GMOS...MET...AND MAV GUIDANCE WITH GREATER WEIGHT WITH THE GMOS
AND ARE FORECAST TO BE IN THE UPPER 40S TO NEAR 50.
ANOTHER AREA OF RAIN WILL MOVE IN LATE SUNDAY AFTERNOON
INTO SUNDAY EVENING FOR THE SECOND ROUND ASSOCIATED WITH THE
DEFORMATION ZONE NORTHWEST OF THE LOW...BUT THIS WILL BE LIGHTER
THAN THE FIRST ROUND. LATE SUNDAY NIGHT INTO MONDAY MORNING WITH
THE COLD AIR ADVECTION...THERE COULD BE SOME WINTRY MIX OF SLEET
AND/OR FREEZING RAIN NORTH AND WEST OF NYC...BUT THERE IS HIGHER
UNCERTAINTY WITH THIS. THIS DEPENDS ON HOW FAST COLDER AIR ADVECTS
IN. LOWS WERE A BLEND OF NAM12/GMOS/MET/MAV AND ARE FORECAST TO BE
MID TO UPPER 30S MOST LOCATIONS AND LOWER 30S FOR SOME
LOCATIONS...PARTICULARLY HIGHER TERRAIN NORTH AND WEST OF NYC.
THE AREA WILL FINALLY BE ON THE WESTERN SIDE OF THE UPPER LEVEL
TROUGH MONDAY WHICH WILL REALLY DECREASE THE SYNOPTIC FORCING WITH
A RIDGING TREND LATER IN THE DAY. THE PRECIPITABLE WATERS WILL
CONTINUE TO LOWER. THESE VALUES WILL BE AROUND 0.5 INCH MONDAY
AFTERNOON INTO MONDAY EVENING. RAIN WILL BE PRETTY LIGHT WITH
DAYTIME TEMPERATURES INCREASING ENOUGH TO ALLOW FOR ANY WINTRY MIX
NORTH AND WEST OF NYC TO CHANGE BACK TO RAIN. THIS TAPERS OFF FROM
WEST TO EAST LATE IN THE DAY. HIGH TEMPERATURES ARE FORECAST TO BE
IN THE UPPER 40S TO NEAR 50 AND USED THE ECS MOS.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MODELS ARE IN GOOD AGREEMENT WITH THE H5 PATTERN THROUGH THE MIDDLE
OF THE WEEK...THEN BEGIN TO GO AWRY WITH THE AMPLITUDE OF THE TROUGH
EXITING THE ROCKIES EXPECTED TO IMPACT THE LOCAL AREA AT THE END OF
THE WEEK.
DEEP LAYERED RIDGING BUILDS IN THE WAKE OF THE CUTOFF WITH THE AXIS
SLIDING ACROSS THE AREA ON TUE. A WEAK COLD FRONT CROSSES THE AREA
LATE TUE NIGHT AND IS FORECAST TO WASH OUT OVER THE AREA ON WED AS A
SHORTWAVE TROUGH PASSES TO THE NORTH. A BROAD RIDGE THEN DEVELOPS
OVER THE EASTERN US AS A TROUGH DIGS OVER THE WEST. UNCERTAINTY IN
THE UPPER FLOW TAKES SHAPE AS THE TROUGH EXITS THE ROCKIES. THIS
SYSTEM WILL BE THE NEXT WEATHER MAKER FOR THE LOCAL AREA AT THE END
OF THE WEEK.
TEMPERATURES WILL BE AT OR ABOVE NORMAL LEVELS THROUGH THE PERIOD.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
LOW PRES TRACKS OFF THE NJ COAST THIS AFTN...THEN SLOWLY DRIFTS E OF
THE REGION THRU MON.
IFR OR LOWER THRU AT LEAST 10Z MON. HIGHEST POTENTIAL FOR LIFR THRU
12-14Z SUN. THE HEAVIEST RAIN WILL OCCUR IN THE NEAR TERM...HOWEVER
VSBY WILL REMAIN RESTRICTED THRU THE TAF PERIOD BY -RA AND BR. ISOLD
TSTMS POSSIBLE THRU AROUND 8Z.
WIND SPEEDS WILL DECREASE THRU 12Z...THEN INCREASE AFT 00Z AS THEY
BACK TO THE N. THE STRONG N WINDS WILL PERSIST THRU MON.
.OUTLOOK FOR 06Z MONDAY THROUGH WEDNESDAY...
.SUN NIGHT...IFR LIKELY. N WINDS 20-30 KT.
.MON...MVFR OR LOWER...MAINLY IN THE MRNG. N WINDS 20-30 KT.
.TUE-WED NIGHT...MAINLY VFR.
.THU...SUB-VFR POSSIBLE IN SHOWERS.
&&
.MARINE...
SEAS WILL CONTINUE TO INCREASE WITH EASTERLY FETCH AHEAD OF
DEVELOPING SURFACE LOW THROUGH THIS EVENING. MORE SOUTHEAST FLOW
TONIGHT IN RESPONSE TO WARM FRONT SHIFTING SLIGHTLY NORTH WILL
KEEP THE HIGHER SEAS. SCA GUSTS WILL DEVELOP LATE TONIGHT AS WELL.
A LITTLE LULL IN WINDS SUNDAY MORNING BUT HIGHER WINDS WILL RETURN
SUNDAY AFTERNOON AND THROUGH SUNDAY NIGHT WITH A STRENGTHENING
NORTHERLY FLOW AND COLD AIR ADVECTION ON THE BACKSIDE OF THE
SURFACE LOW. SCA WILL REMAIN ON THE OCEAN THROUGH SUNDAY NIGHT BUT
WILL BECOME PRESENT ON OTHER WATERS AS WELL SUNDAY AFTERNOON AND
SUNDAY NIGHT. THE SCA CONDITIONS CONTINUE INTO MONDAY AS WELL.
THERE WILL BE THE POSSIBILITY OF GALES ON THE EASTERN OCEAN WATERS
FOR LATE SUNDAY NIGHT THROUGH MONDAY BUT CONFIDENCE IS LESS THAN
50 PERCENT.
WINDS WILL BE DIMINISHING MON NIGHT...BUT WILL LIKELY REMAIN
ABOVE SCA LEVELS...MAINLY ON THE OCEAN WATERS...THROUGH MON NIGHT.
SCA SEAS ON THE EASTERN OCEAN WATERS WILL LIKELY LINGER INTO TUE
MORNING. TRANQUIL CONDS RETURN THEREAFTER WITH A WEAK PRES
GRADIENT OVER THE AREA.
&&
.HYDROLOGY...
AN AVERAGE OF 2 TO 2 1/2 INCHES OF RAIN HAS FALLEN THROUGH EARLY
THIS MORNING. AN ADDITIONAL HALF TO ONE INCH OF RAINFALL IS
POSSIBLE THROUGH DAYBREAK ACROSS LI AND SRN CT AS CONVECTION WORKS
IN FROM THE SOUTH. MINOR URBAN AND POOR DRAINAGE FLOODING WILL
CONTINUE.
THERE IS SOME UNCERTAINTY WITH ADDITIONAL RAINFALL SUN NIGHT
AS A BAND OF MODERATE TO HEAVY RAINFALL FORMS TO THE NW OF THE
LOW TRACK. THE MAIN IMPACT AT THIS TIME LOOKS TO BE ACROSS NE NJ
AND THE LOWER HUDSON VALLEY.
A FLOOD WATCH REMAINS IN PLACE FOR THE LOWER HUDSON VALLEY...NE
NJ...AND SOUTHERN CT.
&&
.TIDES/COASTAL FLOODING...
DUE TO HIGH ASTRONOMICAL TIDES WITH A NEW MOON...THERE IS THE
POSSIBILITY OF LOCALIZED MINOR COASTAL FLOODING NEAR THE TIME OF
HIGH TIDE FOR THE NEXT SEVERAL HIGH TIDE CYCLES. THE BEST CHANCE
FOR THIS WILL BE FOR LOCATIONS ALONG THE COAST OF WESTERN LONG
ISLAND SOUND.
IN ADDITION TO THE WESTERN PORTION OF THE LONG ISLAND SOUND...THE
SOUTH SHORE BACK BAYS OF LONG ISLAND MAY BE SUSCEPTIBLE DURING
HIGH TIDES SUNDAY...PARTICULARLY SUNDAY NIGHT. THE THREAT APPEARS
TO BE LOCALIZED.
&&
.EQUIPMENT...
THE NOAA WEATHER RADIO TRANSMITTER THAT SERVES THE NEW YORK CITY
METROPOLITAN AREA IS CURRENTLY BROADCASTING. THE TRANSMITTER IS
CURRENTLY BEING TESTED TO DETERMINE IF RADIO FREQUENCY INTERFERENCE
CONTINUES ON THE U.S. COAST GUARD CHANNEL 16 TRANSMITTER FOR
INTERNATIONAL DISTRESS...SAFETY AND RESCUE.
FOR MORE INFORMATION SEE THE FOLLOWING PUBLIC INFORMATION
STATEMENT (ALL LOWER CASE):
WWW.WEATHER.GOV/OKX/NYCNWRUPDATE
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH THROUGH LATE TONIGHT FOR CTZ005>012.
NY...FLOOD WATCH THROUGH LATE TONIGHT FOR NYZ067>071.
NJ...FLOOD WATCH THROUGH LATE TONIGHT FOR NJZ002-004-103>108.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT EARLY THIS MORNING FOR
ANZ330-335.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT MONDAY FOR ANZ350-353-355.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
109 AM CDT SUN MAR 30 2014
.DISCUSSION...
321 PM CDT
MAIN FORECAST CONCERNS/CHALLENGES ARE WITH SHOWER/THUNDER CHANCES
MONDAY AND MONDAY NIGHT...AND THEN WITH ACTIVE WEATHER TO CONTINUE
THROUGH LATE IN THE WORK WEEK.
CHALLENGES IN THE NEAR TERM HAVE BEEN WITH THE LINGERING AND SLOW
MOVING LOW STRATUS STILL IN PLACE OVER MUCH OF THE CWA...AS WELL
AS RESULTANT HIGH TEMPERATURES. LATEST VISIBLE SATELLITE IMAGERY
DEPICTING A SLOW SOUTH/SOUTHEAST MOVEMENT TO THE STRATUS BUT WITH
SOME PROGRESS BEING MADE. ALTHOUGH...THIS PROGRESS IS SLOW AND
COINCIDING WITH FURTHER DIURNAL DEVELOPMENT ON THE NORTHERN
PERIPHERY OF THIS CLOUD DECK. MADE EDITS THIS AFTERNOON TO SLOW
THE CLEARING TREND THROUGH 00Z AND WITH AT LEAST PARTLY CLOUDY
SKIES FOR THE SOUTHERN THIRD OF THE CWA THROUGH EARLY THIS
EVENING...BEFORE CLEARING CONTINUES AND MOSTLY CLEAR SKIES
EXPECTED TO PREVAIL OVERNIGHT. DID DROP HIGH TEMPS A COUPLE OF
DEGREES IN SOME PLACES EARLIER THIS AFTERNOON DUE TO THIS CLOUD
COVER...WITH TEMPS STAYING IN THE UPPER 30S OR AROUND 40 UNDER THE
CLOUD COVER AND LOW TO MID 40S FOR AREAS WHICH HAVE OBSERVED MORE
SUNSHINE WITHIN THE LAST COUPLE OF HOURS. ALTHOUGH...ALL LOCATIONS
WILL OBSERVE FALLING TEMPS THIS EVENING AS THE DEPARTING CLOUD
COVER THIS AFTERNOON AND EVENING ONLY AIDS IN A COLD NIGHT
TONIGHT. SURFACE HIGH TO THE WEST/NORTHWEST WILL SHIFT OVERHEAD
TONIGHT WITH WINDS DIMINISHING AND DESPITE WAA BEGINNING
OVERNIGHT...TEMPS ANTICIPATED TO FALL INTO THE 20S ACROSS THE CWA.
MID/UPPER 20S ARE LIKELY FOR MOST LOCATIONS...OUTSIDE OF THE
CITY...WITH SOME LOCATIONS POSSIBLE DIPPING INTO THE LOWER 20S.
QUIET CONDITIONS EXPECTED SUNDAY/SUNDAY NIGHT AS UPPER LEVEL
RIDGING IS ONGOING ACROSS THE REGION. CONTINUED WAA WILL HELP A
WARMER AIRMASS TO SPREAD OVER THE CWA ON SUNDAY WITH TEMPS
EXPECTED TO RISE AROUND 60. DID MAKE SOME MINOR ADJUSTMENTS TO MAX
TEMPS MAINLY TO ACCOUNT FOR PERSISTENT ONSHORE FLOW FOR AREAS IN
CHICAGO AND NORTHWARD...KEEPING TEMPS IN THE LOW TO MID 50S. AFTER
A MILD NIGHT SUNDAY NIGHT...PERSISTENT WAA WILL PROVIDE WELL ABOVE
NORMAL HIGHS IN THE MID TO UPPER 60S. ONSHORE FLOW NOT ANTICIPATED
SO MOST LOCATIONS LIKELY TO OBSERVE THIS WARMTH. WILL HAVE
INCREASING CLOUD COVER ON MONDAY IN ADVANCE OF VORT MAX AND
ATTENDANT SURFACE LOW MOVING EAST OVER THE CENTRAL CONUS. GUIDANCE
IN AGREEMENT WITH DRY CONDITIONS MONDAY MORNING AND THEN WITH
INCREASING CHANCES FOR PRECIP INTO THE AFTERNOON...THOUGH
PRIMARILY FOR THE WESTERN CWA. FOR MONDAY AFTERNOON INTO MONDAY
EVENING...NOT OVERLY CONFIDENT WITH POPS DURING THIS PERIOD AND
HAVE ONLY MADE MINOR CHANGES TO LOW CHANCE/CHANCE POPS. THIS IS
MAINLY DUE TO THE FACT THAT CONFIDENCE IS NOT HIGH WITH REGARDS TO
OVERALL COVERAGE OF PRECIP. WITH LARGE SCALE FORCING FOR ASCENT
SPREADING OVER THE AREA ON MONDAY AS WELL AS MOISTURE INCREASING
OUT AHEAD OF SURFACE LOW AND COLD FRONT...DEVELOPMENT SHOULD NOT
BE TOO MUCH OF AN ISSUE...AND EXPECT POPS TO LIKELY CHANGE DURING
THIS PERIOD WITH SUCCESSIVE FORECASTS. STILL NOT OVERLY CONFIDENT
WITH THUNDER DEVELOPMENT AS WELL...AND SO HAVE MADE LITTLE CHANGES
DURING THIS TIME KEEPING CHANCE THUNDER IN THE GRIDS. WILL NEED TO
MONITOR THE EXTENT OF THE MOISTURE RETURN AND RESULTANT
INSTABILITY...WHICH AT THIS TIME IS APPEARING RATHER WEAK.
WILL STILL NEED TO MONITOR AN EXPECTED ACTIVE WEATHER PATTERN FOR
THIS NEXT WEEK AS GUIDANCE IS IN AGREEMENT WITH SEVERAL FEATURES
PUSHING ACROSS THE REGION. ALTHOUGH...TIMING AND EVOLUTION
AGREEMENT IS LACKING WHICH WILL BE KEY WITH PRECIP TYPE...WHICH
COULD STILL BE OF FROZEN FORM VERY LATE IN THE FORECAST PERIOD.
RODRIGUEZ
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* WINDS CALM OR LIGHT AND VARIABLE THROUGH SUNRISE...THEN
SOUTHEAST TO SOUTH MOST OF THE DAY.
* LLWS POSSIBLE SUNDAY NIGHT.
LENNING
//DISCUSSION...UPDATED 06Z...
SKIES HAVE CLEARED AND WINDS HAVE GONE CALM UNDER A RIDGE PASSING
OVERHEAD EARLY THIS MORNING. SO FAR VSBYS HAVE STAYED UP AS A
RESULT OF DECENT SPREADS BETWEEN TEMPERATURES AND DEWPOINTS. THE
PREFERRED WIND DIRECTION WILL BE SOUTHEASTERLY AS THE RIDGE
MOVES OUT LATER THIS MORNING. MORE OF A SOUTHERLY COMPONENT
DEVELOPS BY THE AFTERNOON AHEAD OF THE NEXT LOW PRESSURE
SYSTEM...BUT WINDS APPEAR TO REMAIN ON THE EAST SIDE OF SOUTH AND
DO NOT DEVELOP A WESTERLY COMPONENT. AGREE WITH EARLIER THINKING
REGARDING LACK OF AN EASTERLY LAKE BREEZE AT TERMINALS THIS
AFTERNOON DESPITE SOME COOL ONSHORE COMPONENT BETWEEN THE
TERMINALS AND THE WATERFRONT.
AN INCREASING PRESSURE GRADIENT WILL SUPPORT STRENGTHENING
SOUTHERLY FLOW TONIGHT INTO MONDAY. SURFACE WINDS LIKELY WILL NOT
INCREASE OVERNIGHT WITH A COOL SURFACE LAYER...BUT STRONGER WINDS
ALOFT MAY RESULT IN LOW LEVEL WIND SHEAR ABOVE THAT SURFACE LAYER.
WILL MONITOR FOR LATER UPDATES.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH IN ALL ELEMENTS TODAY...THOUGH DEVELOPMENT OF A LAKE BREEZE IS
NOT OUT OF THE QUESTION.
* MEDIUM IN DEVELOPMENT OF LLWS TONIGHT.
LENNING
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...NEAR DUE SOUTH WINDS GUSTING TO AROUND 30 KT IN THE
AFTERNOON. CHC OF TSRA DURING THE EVE AND A SLGT CHC
OF LIGHT RAIN/SNOW DURING THE OVERNIGHT.
TUESDAY...MORNING MVFR POSSIBLE.
WEDNESDAY...EAST FLOW WITH RAIN AND MVFR/IFR LIKELY.
THURSDAY...EAST FLOW WITH CHC OF RAIN AND POSSIBLE IFR.
FRIDAY...CHC OF RAIN DURING THE DAY. SLGT CHC OF RAIN/SNOW DURING
THE NIGHT.
MTF
&&
.MARINE...
251 PM CDT
NORTH-NORTHEASTERLY ONSHORE FLOW ACROSS NORTHEASTERN ILLINOIS AND
NORTHWESTERN INDIANA CONTINUES UP AROUND 20S OUT AHEAD OF AN AREA OF
HIGH PRESSURE. THIS FLOW IS BIT STRONGER THAN PREVIOUSLY
THOUGH...AND AS A CONSEQUENCE OF THIS...I HAVE ISSUED A SMALL CRAFT
ADVISORY THROUGH THIS EVENING...MAINLY FOR THE EXPECTATION THAT
WAVES ARE AT OR JUST ABOVE THE 4 FOOT MARK. THESE WINDS WILL ABATE
THIS EVENING...THEN GRADUALLY BECOME EAST-SOUTHEASTERLY OVERNIGHT
TONIGHT AS THE SURFACE RIDGE SHIFTS OVER THE LAKE.
LOW PRESSURE WILL BE IN THE PROCESS OF DEVELOPING ACROSS THE CENTRAL
HIGH PLAINS ON SUNDAY...AND THIS WILL RESULT IN A CONTINUAL
SOUTH-SOUTHEASTERLY FLOW PATTERN ACROSS THE LAKE FOR THE NEXT COUPLE
OF DAYS. THE LOW IS EXPECTED TO TRACK EAST-NORTHEASTERLY TO THE
UPPER MISSISSIPPI VALLEY BY LATE MONDAY EVENING...THEN SHIFT ACROSS
THE UPPER GREAT LAKES BY TUESDAY EVENING. OVERALL...THIS WILL RESULT
IN INCREASING SOUTHERLY WINDS MONDAY AND INTO MONDAY
EVENING...LIKELY TO AROUND 30 KT. OVERALL...IT APPEARS THAT WARMER
AIR MOVING OVER THE LAKE WILL RESULT IN A STABLE MARINE
LAYER...WHICH WOULD RESULT IN LOWER CHANCES FOR GALES.
HOWEVER...SOME STRONGER WINDS NEARLY GALE FORCE ARE POSSIBLE WITH
THIS SYSTEM...ESPECIALLY MONDAY NIGHT AS THE LOW AND COLD FRONT
APPROACH THE LAKE. WESTERLY FLOW WILL SET UP TUESDAY IN THE WAKE OF
THIS SYSTEM.
ANOTHER STORM SYSTEM LOOKS TO TAKE AIM ON THE LOWER GREAT LAKES
LATER IN THE PERIOD...AROUND THURSDAY. THIS COULD RESULT IN A PERIOD
OF SOME ENHANCED NORTHEASTERLY WINDS INTO THE END OF THE UP COMING
WEEK.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
1150 PM CDT Sat Mar 29 2014
.DISCUSSION...
ISSUED 822 PM CDT Sat Mar 29 2014
Have made adjustments to sky grids to push clearing a bit faster
than current package. Otherwise going forecast looks good.
Surface ridge moving into forecast area attm and winds have
decoupled despite significant northwest winds above the boundary layer
associated with strengthening system over the central
Appalachians. This flow above developing inversion continues to
erode cloud cover and advect drier air into Illinois from
northwest to southeast. Trapped moisture under the inversion may
lead to some patchy ground fog. Attm, it appears that lowest vsbys
should be around 3SM so will leave out of grids/zones but keep it
in eastern TAF sites. Latest Lamp guidance in good agreement with
ongoing forecast for tonight`s lows.
Barker
&&
.AVIATION...
ISSUED 1150 PM CDT Sat Mar 29 2014
Surface ridge is oriented northeast to southwest near the Illinois
River late this evening. Clear skies and light winds continue.
Still somewhat concerned with potential for ground fog later
tonight under almost perfect radiational cooling conditions,
particularly in areas that had precipitation last night. Will
introduce IFR vsbys late tonight given that they are beginning to
show a downward trend. KDEC had a bit more drying time this
afternoon than KCMI and will keep lowest vsbys MVFR there. Will
also introduce MVFR vsbys at KSPI. Even though the temp-dew point
spread is higher, several airports nearby (IJX, 3LF, TAZ) are
already indicating reduced vsbys.
Southerly flow develops on the back side of the ridge as it moves
east of the area Sunday. Winds will likely become gusty,
particularly across western terminals during the afternoon. Some
Cirrus will be likely during the afternoon as the next system
develops over the central high plains.
Barker
&&
.PREV DISCUSSION...
ISSUED 228 PM CDT Sat Mar 29 2014
The progressive weather pattern will provide active weather next
week as several storm systems affect Illinois. The latter half of
this weekend looks pleasant with plenty of sunshine pushing temps
above normal. However, by Monday afternoon the first system will
bring chances of rain, and the onset of a return to cooler
conditions. Heavier rains in the Wed to Thur time frame could
accumulate between 1-2" in some locations. Localized flooding may
develop.
SHORT TERM...Tonight through Sunday night.
Low clouds have been keeping high temps generally below forecast
highs this afternoon. A narrow break in the cloud cover allowed
Peoria to spike up about 10 degrees in a couple hours, and create
a large temperature gradient over short distances in our forecast
area. The RAP and HRRR layer RH indicate that some clearing should
continue west of I-57 between 23z and 03z. Lows tonight will be
dependent on cloud cover. Areas east of I-57 may remain cloudy
until just after midnight as NE surface winds continue to drag low-
level moisture from the Great Lakes into eastern IL. Even a few
hours of clearing later tonight should allow eastern areas to cool
off to near guidance lows, especially with surface dewpoints
dipping into the upper 20s in many locations.
Sunday will see mid level temps climb 5 to 7C during the day as an
upper level ridge axis advances into eastern IL by 00z/7pm Monday.
Near full sunshine should combine with increasing south winds to
push highs about 10 to 15 deg above normal (60s), which will be a
welcome taste of Spring. An tightening pressure gradient ahead of
the next system will keep south winds up in the 10 to 20 mph range
even Sunday night. So despite clear skies Sunday night, south
winds will keep a mixed boundary layer and allow lows to be in the
upper 40s west and around 40 east.
LONG TERM...Monday through Saturday.
Increasing clouds on Monday will not prohibit highs from climbing
well into the 60s for one more day, as south-southeast winds
increase into the 25 to 35 mph range. By Monday afternoon, a
parent low pressure system will advance from eastern Nebraska to
southeastern Minn, as a cold front reaches the western border of
IL by 00z/7pm Monday. Pre-frontal storms will have a high amount
of wind shear and storm relative helicity available, along with
steep lapse rates, but a limited amount of moisture. Forecast
soundings show the best instability may be at or above 750 mb, so
any thunderstorms will be elevated to begin. Due the strong jet
dynamics and wind shear with this system, some of the storms could
begin rotating and produce hail and strong winds Monday afternoon
and evening ahead of the cold front.
Showers and storms should end from west to east by midnight in the
post-frontal subsidence and dry air intrusion. Clouds will likely
clear out behind the line of precip, so lows in the NW could dip
below freezing, while southeast areas remain in the low 40s.
The brief pocket of cold air is forecast to brush across N IL late
Mon night and Tues morning, which will keep highs about 10-15 deg
colder than Monday. High temps will range from around 50 near
Galesburg to around 60 by Lawrenceville.
Return flow behind the cooler high pressure will bring increasing
moisture Tuesday night, with a few showers possible before sunrise
on Wednesday. Thunderstorm chances will increase along and south
of a warm front that is expected to develop directly across
central IL from west to east. Storm chances will be higher in the
warm sector roughly south of a line from Rushville to Champaign.
Instability may have a better chance of being based closer to the
surface as dewpoints climb into the 50s Wed night south of the
warm front, which will be close to overnight low temps.
Precipitable water values are expected to climb over an inch Wed
night through Thursday as low pressure tracks northeast along the
warm front. Locally heavy rain may occur in any thunderstorms,
with training of storms over the same area also boosting rainfall
amounts. Localized flooding could develop in low areas, as
rainfall amounts possibly reach between 1 and 2 inches by Thursday
afternoon.
A wide range of temps will occur across C IL from north to south
from Tues night through Thursday as the warm front lingers across
the middle of the area. The temp spreads could be 20 to 25 degrees
from north to south for highs and lows.
There is a spread of solutions for how the surface and upper level
systems progress from after Thursday. The GFS lingers the upper
trough farther west Thurs night, then brings a secondary surface
low and another round of rain showers across IL on Friday. The
ECMWF is more progressive and drys out the air column after the
low on Thursday. So low chance and slight chance PoPs were
included Thurs night and Friday to account for a slower
progression.
There is some agreement that another push of cold air will keep
temps below normal for Friday and Saturday, with Saturday looking
dry at this time.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
129 AM EDT SUN MAR 30 2014
.SYNOPSIS...
ISSUED AT 758 PM EDT SAT MAR 29 2014
SKIES WILL CONTINUE TO CLEAR THIS EVENING. OVERNIGHT LOWS WILL BE
COLD IN THE LOWER TO MID 20S. TEMPERATURES WILL THEN WARM UP
NICELY ON SUNDAY INTO THE LOWER TO MID 50S. EVEN WARMER
CONDITIONS ARE ANTICIPATED ON MONDAY AS HIGH TEMPERATURES RISE
INTO THE MID 60S UNDER PARTLY CLOUDY SKIES.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 328 PM EDT SAT MAR 29 2014
NO SIG ISSUES TO WORRY ABOUT FOR THE SHORT TERM AS RAIN/SNOW THAT
HAS FELL ACROSS MUCH OF THE SOUTHERN GREAT LAKES TODAY WAS NEARLY
OUT OF THE FORECAST AREA. FOCUS WILL SHIFT TO CLEARING TONIGHT AND
HOW WARM WE GET ON SUNDAY.
BY IN LARGE THE HEAVIER SNOWBANDS HAVE DIMINISHED WITH REMAINING
RAIN/SNOW ACROSS PORTIONS OF HENRY/PUTNAM AND ALLEN COUNTIES IN
OHIO. SFC LOW WAS OVER NE TENNESSEE AT 18Z AND SLOWLY DEEPENING
WITH AN INCREASING PRESSURE GRADIENT AROUND IT. THIS WILL KEEP
SOMEWHAT BREEZY CONDITIONS MAINLY EAST INTO THIS EVENING BEFORE THE
LOW SHIFTS EAST. LOW CLOUDS HAVE BEEN SLOW TO ERODE IN THE WEST AND
NORTH WITH NAM AND RUC VARYING ON HANDLING OF CLEARING. RUC 925/850
MB RH PLOT HAVE HANDLED THINGS WELL AND LINGER LOW CLOUDS INTO LATE
EVENING WITH NAM MUCH QUICKER ERODING MSTR. WITH VIS SAT SHOWING
HINTS AT SOME THIN SPOTS STARTING TO APPEAR SO HAVE TRIED TO BLEND
THE 2 MODELS WHICH STILL BRINGS GENERALLY CLEAR SKIES BY LATE
EVENING. LOWS WILL DROP INTO THE 20S DESPITE COLDEST AIR WITH THE
SYSTEM ALREADY EAST OF THE REGION AND WAA UNDERWAY LATER TONIGHT.
SOME OF THIS WAA WILL BE REALIZED ON SUNDAY AS LOTS OF SUNSHINE
ALLOWS FOR MIXING THROUGH AT LEAST 900 MB AND MAYBE A BIT HIGHER
YIELDS HIGHS IN THE 50S. WOULDN`T BE ENTIRELY SURPRISED TO SEE SOME
UPR 50S TO NEAR 60 IN FAR W/SW AREAS.
&&
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 PM EDT SAT MAR 29 2014
VERY FEW CHANGES TO OVERALL IDEA IN LONG TERM PERIOD. AN ACTIVE
PATTERN WILL CONTINUE THROUGH THE PERIOD WITH NUMEROUS SHORT WAVES
AND A QUASI STATIONARY BOUNDARY IN THE REGION. THIS SHOULD LEAD TO
RATHER WET PERIOD WITH TEMPERATURES A LITTLE CLOSER TO NORMAL FOR
EARLY APRIL.
RIDGE WILL BE OVER THE AREA SUNDAY NIGHT PROVIDING CLEAR SKIES AND
LIGHT WINDS. LOWS EXPECTED IN THE LOWER 30S EAST UNDER RIDGE AXIS TO
UPPER 30S WEST WHERE WARM AIR ADVECTION ON BACK SIDE OF RIDGE WILL
BE INCREASING. THIS WARMING SHOULD TRANSLATE TO A LARGE DIURNAL
SWING ON MONDAY AS STRONG MIXING DEVELOPS AND WARM AIR ALOFT IS
ALLOWED TO MIX TO SURFACE. SHOULD BECOME BREEZY AS WELL TO HELP
BOOST TEMPERATURES. INCREASING HIGH CLOUDS IN AFTERNOON MAY TEMPER
WARM UP BY A FEW DEGREES DEPENDING ON HOW THICK CLOUD CANOPY IS AND
TIMING OF IT. STILL EXPECT 60S ALL AREAS WITH RUN AT MID TO UPPER
60S ACROSS THE AREA IF SKIES REMAIN MOSTLY SUNNY THROUGH AFTERNOON
PEAK HEATING.
NEXT OF MANY SHORT WAVES MOVES THROUGH THE LAKES REGION MONDAY NIGHT
WITH A TRAILING COLD FRONT THROUGH THE CWA EARLY TUESDAY MORNING.
ENOUGH MOISTURE AND WEAK LIFT TO WARRANT LOW CHANCE POPS BUT
STRONGEST FORCING TO THE NORTH CLOSER TO MAIN LOW. WARMEST TEMPS OF
THE DAY LIKELY IN MORNING BEFORE FROPA BUT DRYING PROFILES TUE
AFTERNOON SUGGEST SUN COULD ALLOW FOR SOME REBOUND SIMILAR TO WHAT
SOME LOCATIONS EXPERIENCED FRIDAY.
DETAILS REMAIN UNCERTAIN FOR REMAINDER OF LONG TERM WITH
AFOREMENTIONED COLD FRONT BECOMING STATIONARY NEAR OR JUST SOUTH OF
CWA. SEVERAL SHORT WAVES ARE EXPECTED WEDNESDAY INTO FRIDAY WITH
ASSOCIATED SURFACE WAVES RIPPLING ALONG FRONTAL BOUNDARY. SEVERAL
CHANCES FOR RAINFALL DURING THE PERIOD WITH UNCERTAINTY IN TIMING.
THUS A CONTINUATION OF BROAD HIGH CHANCE POP CONTINUES WITH FURTHER
INCREASE LIKELY AS TIME NEARS. WITH INCREASING PWATS AND THETA E
AIR...MODERATE TO LOCALLY HEAVY RAINFALL AMOUNTS STILL PLAUSIBLE.
TEMPS DURING THIS PERIOD LIKELY NEAR NORMAL SOUTH AND SLIGHTLY BELOW
NORMAL NORTH BUT IF FRONT WAVERS NORTH OR SOUTH...SIGNIFICANT
CHANGES IN TEMPERATURE FORECASTS WOULD BE EXPECTED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 128 AM EDT SUN MAR 30 2014
ELONGATE SFC RIDGE EXTENDING FM SE CANADA SWWD INTO THE LWR MS
VALLEY WILL SHIFT EWD INTO THE ERN OH VALLEY ON MON. LT WINDS AND
CLR SKIES WILL RESULT AT THE TERMINALS THROUGH THE PD.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...BENTLEY/MURPHY
SHORT TERM...FISHER
LONG TERM...LASHLEY
AVIATION...T
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AREA FORECAST DISCUSSION
NWS CARIBOU ME
144 AM EDT SUN MAR 30 2014
.SYNOPSIS...
LOW PRESSURE OVER THE MID ATLANTIC STATES WILL TRACK SLOWLY EAST...
SOUTH OF THE AREA TONIGHT INTO EARLY NEXT WEEK
&&
.NEAR TERM /THROUGH TODAY/...
UPDATE...
ADJUSTED POPS TO 100 PERCENT ACROSS DOWNEAST TO MATCH UP WITH
LATEST RADAR IMAGERY. ALSO ADJUSTED HOURLY TEMPERATURES EARLY
THIS MORNING PER LATEST OBSERVATIONS. THINK THE THREAT OF
ANY -FZRA ACROSS INTERIOR DOWNEAST IS MINIMAL AT BEST SO REMOVED
FROM OVERNGHT FORECAST. REST IOF FORECAST REMAINS ON TRCAK.
ORGNL DISC: AT THE START OF THE PERIOD THE MAJOR MODELS ARE
SHOWING THE NEXT SYSTEM TO AFFECT OUR AREA CENTERED OVER THE CNTRL
PORTIONS OF THE NC/VA BORDER...WITH A WARM FRONT EXTENDING NORTH
TO THE SW COAST OF MAINE. THE MODEL INDICATE THAT THE LOW IS STILL
DYNAMIC AT THIS POINT...BUT SHOWING THAT THE UPPER LEVEL LOW IS
STARTING TO BECOME VERTICALLY STACKED WITH THE SURFACE LOW...THE
BEGINNING PROCESS OF BECOME COLD CORE. BY MRNG THE LOW MOVES NE TO
THE NJ COAST...PRECIP SPREADS ACROSS ERN MAINE INTO NRN MAINE.
PCPN WILL BE SNOW...WITH SLEET AND FREEZING RAIN MIXED IN ACROSS
THE INTERIOR DOWNEAST AND EAST CNTRL MAINE. AT THIS TIME ALL
MODELS SHOWING A CLOSED LOW AT 500MB AND THE SFC LOW NEARLY
VERTICALLY STACKED. BY THE END OF THE PERIOD...THE BULK OF THE
PCPN MOVES EAST INTO NEW BRUNSWICK...THE LOW DRIFTS NORTH ALONG
THE NJ COAST TO JUST SOUTH OF LONG ISLAND. THE UPPER LOW AND SFC
LOW WILL BE VERTICALLY STACKED. THE GFS...GEM...AND ECMWF SHOW A
NEW LOW IN THE ERN GULF OF MAINE THAT WILL BECOME THE NEW PRIMARY
LOW FOR THIS SYSTEM AS IT TRACKS TOWARD NEW BRUNSWICK.
LOADED THE HRRR MIN TEMP FOR THE OVRNGT...GEM MAX TEMP FOR
TOMORROW. INTERPOLATED FROM MIN TO MAX FOR HRLY TEMPS. USED A
BLEND OF NAM/GFS/GEM/ECMWF FOR HRLY DP/SKY/WND/POP. ADDED 15
PERCENT TO WINDS FOR GUSTS OVER LAND...25 PERCENT OVER WATERS.
LOADED NAWAVE 4 FOR SEAS IN THE COASTAL WATERS.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY/...
A VERTICALLY STACKED SURFACE/UPPER LOW WILL BEGIN TO MOVE SLOWLY
NORTHEAST SUNDAY NIGHT. A NEARLY STATIONARY FRONTAL BOUNDARY WILL
EXTEND NORTHEAST FROM THE SURFACE LOW. ISENTROPIC LIFT AND
OVERRUNNING IN THE VICINITY OF THE FRONT WILL SUPPORT PRECIPITATION
ACROSS THE FORECAST AREA SUNDAY NIGHT. HOWEVER...THE PROXIMITY OF
THE FRONT TO THE COAST REMAINS UNCERTAIN. HAVE BASED THE FORECAST
ON A SLOWER MOVEMENT OF THE SURFACE LOW AND THE FRONT REMAINING
CLOSER TO THE COAST WHICH WILL KEEP MORE EXTENSIVE PRECIPITATION
ACROSS THE FORECAST AREA. HIGH PRESSURE NORTH OF MAINE WILL
CONTINUE TO PROVIDE LOW LEVEL COLD AIR ACROSS THE FORECAST AREA
SUNDAY NIGHT INTO MONDAY. HOWEVER...WARMER AIR ALOFT WILL KEEP A
WINTRY MIX ACROSS MUCH OF THE FORECAST AREA SUNDAY NIGHT. A WINTRY
MIX WILL PERSIST ACROSS NORTHERN AND CENTRAL PORTIONS OF THE
FORECAST AREA SUNDAY NIGHT...WITH RAIN TRANSITIONING TO A WINTRY
MIX ACROSS DOWNEAST AREAS. WINTER STORM WARNINGS WILL REMAIN IN
EFFECT ACROSS NORTHERN AREAS SUNDAY NIGHT...WITH WINTER WEATHER
ADVISORIES ACROSS CENTRAL AREAS AND INTERIOR DOWNEAST PORTIONS OF
THE FORECAST AREA. HAVE HELD WITH THE SLOWER MOVEMENT OF THE
SYSTEM MONDAY...WHICH WILL KEEP LIGHT PRECIPITATION ACROSS THE
FORECAST AREA. ACROSS NORTHERN AREAS EXPECT EXPECT A LIGHT WINTRY
MIX...WITH A WINTRY MIX TRANSITIONING TO RAIN ACROSS CENTRAL AND
DOWNEAST AREAS. THE SURFACE/UPPER LOW WILL MOVE EAST MONDAY NIGHT
WHILE HIGH PRESSURE SLOWLY BUILDS SOUTH WITH DECREASING RAIN/SNOW
SHOWER CHANCES ACROSS THE FORECAST AREA. A SLIGHT CHANCE OF
SHOWERS COULD PERSIST DOWNEAST TUESDAY WITH THE EXITING LOW WHILE
HIGH PRESSURE BUILDS ACROSS NORTHERN MAINE. TEMPERATURES WILL BE
AT SLIGHTLY BELOW NORMAL LEVELS MONDAY/TUESDAY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
LOW PRESSURE WILL BE MOVING AWAY TUESDAY NIGHT AS A RIDGE OF HIGH
PRESSURE BUILDS IN FROM THE WEST. THIS WILL BRING DRY AND RELATIVELY
MILD WEATHER TUESDAY NIGHT INTO WEDNESDAY. A WEAK TROUGH MAY MOVE
THROUGH ON THURSDAY BRINGING SOME CLOUDS AND PERHAPS LIGHT SHOWERS.
OTHERWISE, THE DAY SHOULD REMAIN MOSTLY CLOUDY. HIGH PRESSURE SHOULD
THEN BUILD IN BRINGING DRIER AND SEASONABLY MILD CONDITIONS ON
FRIDAY. GOING INTO THE WEEKEND, LOTS OF UNCERTAINTY REGARDING
WHETHER OR NOT A BLOCKING RIDGE OVER EASTERN CANADA CAN MAINTAIN THE
DRY WEATHER. THE GFS KEEPS CONDITIONS DRY WHILE THE ECMWF BRINGS A
TROUGH OF LOW PRESSURE THROUGH WITH A CHANCE FOR SOME RAIN OR SNOW
SHOWERS. IN THE FORECAST WILL HAVE LOW CHANCE FOR RAIN OR SNOW
SHOWERS NEXT WEEKEND. CURRENTLY DOES NOT LOOK LIKE ANY MAJOR STORMS
ARE EXPECTED THROUGH NEXT WEEKEND, AND TEMPERATURES WILL BE NEAR
NORMAL WHICH WILL BE CONSIDERABLY MILDER THAN THE VERY COLD
CONDITIONS WE HAVE HAD IN MARCH.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
NEAR TERM: DETERIORATING CONDITIONS SOUTH TO NORTH AS THE LOW
MOVES INTO THE AREA. MVFR CONDITIONS BHB...ALL OTHER SITES VFR TO
START THE PERIOD THIS EVENING. BY 9PM IFR CONDITIONS BHB IN
RAIN...BGR RAIN BCMG MXD. IFR CONDITIONS MOVE INTO
HUL...PQI...CAR...FVE AFT 3AM...PCPN SNOW BCMG MXD AT HUL TOMORROW
AFTN. IFR CONDITION WILL REMAIN ACROSS THE AREA THROUGH THE END OF
THE PERIOD. PCPN TYPE SN FOR FVE...SN MAY MIX WITH PL BRIEFLY IN
AFTN IN PQI AND CAR.
SHORT TERM: IFR/LIFR CONDITIONS ARE EXPECTED ACROSS THE REGION
SUNDAY NIGHT INTO EARLY MONDAY...WITH MVFR/IFR CONDITIONS LATER
MONDAY. OCCASIONAL MVFR CONDITIONS COULD PERSIST ACROSS THE
REGION MONDAY NIGHT. OCCASIONAL MVFR CONDITIONS COULD PERSIST
ACROSS DOWNEAST AREAS EARLY TUESDAY. OTHERWISE...VFR CONDITIONS
ARE EXPECTED ACROSS THE REGION TUESDAY. VFR CONDITIONS ARE EXPECTED
ACROSS THE REGION WEDNESDAY. VFR CONDITIONS ARE EXPECTED ACROSS
NORTHERN AREAS THURSDAY...WITH OCCASIONAL MVFR CONDITIONS POSSIBLE
DOWNEAST.
&&
.MARINE...
NEAR TERM: 1000 PM UPDATE...WITH NO INTERIM SCA HDLN AND WINDS FCST
TO REACH LOW END GALE FORCE GUSTS IN ABOUT 12 TO 15 HRS...WE
THOUGHT IT BEST TO CONVERT THE GALE WATCH TO A WARNING FOR THE
SAME PD OF TM ADVERTISED IN THE WATCH...NAMELY SUN AFTN THRU
LATE MON NGT...WITH THE 18Z GFS ADVERTISING GALE FORCE WIND GUSTS
FOR APPROXIMATELY THIS TM PD.
ORGNL DISC...THE LOW WILL TRANSIT SLOWLY SOUTH OF OF THE GULF OF
MAINE. TODAYS TRACK IS FARTHER SOUTH THAN WAS PREVIOUS FORECASTED.
WINDS STILL CALL FOR MARGINAL GALE FORCE WINDS FOR TOMORROW. WILL
CONTINUE THE GALE WATCH.
SHORT TERM: MARGINAL GALE CONDITIONS ARE POSSIBLE SUNDAY NIGHT
INTO EARLY MONDAY NIGHT WHICH COULD REQUIRE GALE WARNINGS.
VISIBILITIES WILL BE REDUCED IN RAIN SUNDAY NIGHT INTO EARLY
MONDAY NIGHT...WITH LINGERING RAIN/SNOW SHOWERS POSSIBLE LATER
MONDAY NIGHT INTO TUESDAY.
&&
.HYDROLOGY...
A FLOOD WATCH CONTINUES FOR DOWNEAST MAINE SUNDAY THROUGH MONDAY
AFTERNOON. THE PRECIPITATION ASSOCIATED WITH THE UPCOMING STORM
WILL LIKELY FALL MAINLY AS RAIN OR FREEZING RAIN IN THESE AREAS,
ESPECIALLY ALONG THE COAST. TOTAL LIQUID PRECIPITATION AMOUNTS OF
UP TO 3 INCHES ARE EXPECTED. IN ADDITION TO THIS RAIN...TEMPERATURES
WILL REMAIN NEAR OR ABOVE FREEZING THROUGH SUNDAY ADDING SNOWMELT
TO THE EQUATION. THE SNOWPACK IN THESE AREAS IS HIGHLY VARIABLE,
RANGING FROM AROUND 6 INCHES ALONG THE COAST TO 2 FEET OR MORE IN
THE INTERIOR. THERE IS 2 TO 4 INCHES OF WATER CONTAINED IN THE
PACK ALONG THE COAST WITH 6 TO 8 INCHES FURTHER INLAND. WHILE THE
DEEPER SNOW WILL BE ABLE TO ABSORB SOME OF THE RAIN...MUCH OF IT
WILL BECOME RUNOFF IN ADDITION TO THE SNOWMELT. THIS MEANS
DOWNEAST AREAS COULD POTENTIALLY SEE 4 INCHES OR MORE OF TOTAL
RUNOFF. RIVERS WILL LIKELY RISE SUBSTANTIALLY AND POTENTIALLY
CAUSE RIVER ICE TO BREAK UP...ESPECIALLY IN THOSE PLACES WHERE
THE ICE COMPLETELY FLUSHED OUT IN JANUARY (MEANING THE ICE THERE
NOW IS RELATIVELY WEAK). FOR THOSE RIVER STRETCHES THAT ARE ICE
FREE...ICE COVER UPSTREAM MAY BREAK UP AND COLLECT DOWNSTREAM. IN
ADDITION TO THE POTENTIAL FOR ICE JAMS, THIS AMOUNT OF RAINFALL
AND RUNOFF WILL LIKELY LEAD TO PONDING OF WATER ON ROADWAYS AND
MINOR FLOODING OF LOW-LYING POOR DRAINAGE AREAS. IN ADDITION,
TIDAL LOCATIONS SUCH AS BANGOR WILL HAVE TO BE WATCHED CLOSELY
AROUND THE TIME OF HIGH TIDE. THE CURRENT OFFICIAL NATIONAL
WEATHER SERVICE FORECAST FOR THE PENOBSCOT RIVER AT BANGOR BRINGS
THE GAGE WITHIN 1 FOOT OF FLOOD STAGE WITH HIGH TIDE SUNDAY
MORNING. PERSONS WITH INTERESTS ALONG WATERWAYS OR IN FLOOD-PRONE
LOCATIONS ACROSS HANCOCK...WASHINGTON AND SOUTHERN PENOBSCOT
COUNTIES SHOULD STAY TUNED FOR ADDITIONAL INFORMATION ON THIS
SYSTEM.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...WINTER STORM WARNING FROM 6 AM THIS MORNING TO 8 AM EDT MONDAY
FOR MEZ001-002.
WINTER STORM WARNING UNTIL 8 AM EDT MONDAY FOR MEZ003>006-010.
WINTER WEATHER ADVISORY UNTIL 8 AM EDT MONDAY FOR MEZ011-
015>017-031-032.
FLOOD WATCH FROM 8 AM EDT THIS MORNING THROUGH MONDAY
AFTERNOON FOR MEZ015>017-029-030.
GALE WARNING FROM NOON TODAY TO 4 AM EDT TUESDAY FOR MEZ029.
MARINE...GALE WARNING FROM NOON TODAY TO 4 AM EDT TUESDAY FOR
ANZ050>052.
&&
$$
AREA FORECAST DISCUSSION
NWS GAYLORD MI
311 AM EDT SUN MAR 30 2014
.SYNOPSIS...
ISSUED AT 309 AM EDT SUN MAR 30 2014
HIGH PRESSURE WILL REMAIN IN CONTROL OF THE WEATHER THROUGH
MONDAY...BRINGING PLENTY OF SUNSHINE AND INCREASINGLY WARMER
TEMPERATURES. A FRONT CROSSING THE REGION LATE MONDAY NIGHT AND
EARLY TUESDAY WILL BRING A CHANCE FOR SOME LIGHT SHOWERS...ALONG
WITH A RETURN TO COOLER WEATHER. RAIN MAY MIX WITH...OR EVEN CHANGE
OVER...TO A BIT OF SNOW ON TUESDAY...BUT NO ACCUMULATIONS ARE
EXPECTED. COOL WEATHER WILL CONTINUE FOR THE MIDDLE AND END PORTIONS
OF THE WEEK...WITH ANOTHER CHANCE FOR A WINTRY MIX OF PRECIPITATION
THURSDAY AND FRIDAY.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 309 AM EDT SUN MAR 30 2014
HIGH IMPACT WEATHER POTENTIAL: NONE.
PATTERN SUMMARY: AN EARLY MORNING LOOK AT THE PATTERN ACROSS THE
CONUS REVEALS AN ACTIVE SETUP...WITH LOW PRESSURE SYSTEMS ALONG BOTH
COASTS...AND A NARROW RIDGE OF HIGH PRESSURE IN BETWEEN THESE
SYSTEMS... ARCHING FROM QUEBEC...THROUGH THE GREAT LAKES AND DOWN
THE MISSISSIPPI VALLEY. THIS RIDGE AXIS CURRENTLY LIES JUST WEST OF
THE FORECAST AREA...WITH A RIBBON OF CLEARING ALLOWING LOW
TEMPERATURES TO FALL RAPIDLY AS BOUNDARY LAYER WINDS DECOUPLE.
LOOKING FORWARD THROUGH THE SHORT TERM FORECASTS REQUIRES US TO LOOK
UPSTREAM...AND...SOMEWHAT DIFFERENTLY THAN WE HAVE SEEN OF
LATE...MUCH OF WHAT IS UPSTREAM IS DOMINATED BY PACIFIC...MARITIME
POLAR AIR...WITH ANY ARCTIC AIR NOW BOTTLED UP NORTH OF THE REGION.
THIS PACIFIC FLOW WILL RESULT IN LEE-SIDE CYCLOGENESIS EAST OF THE
ROCKIES DURING THE DAY TODAY...WITH THIS LOW PRESSURE DEEPENING AND
BEGINNING TO DEPART TO THE NORTH AND EAST BY THE END OF THIS PERIOD
AROUND DAYBREAK MONDAY. THE DOWNSTREAM LONGWAVE TROUGH IS MUCH
SLOWER MOVING...AND THE DEVELOPING SQUEEZE PLAY IN BETWEEN THESE
FEATURES WILL FORCE HEIGHTS TO BUILD OVER THE GREAT LAKES WITH QUIET
AND MODERATING CONDITIONS EXPECTED FOR NORTHERN MICHIGAN. CERTAINLY
A WELCOME REPRIEVE FROM AN EXCEPTIONALLY COLD MONTH OF MARCH.
THROUGH DAYBREAK: TEMPERATURES WILL CONTINUE TO TUMBLE THROUGH THE
TEENS GIVEN CLEAR SKIES AND CALM-LIGHT WINDS. ALSO CAN/T RULE OUT
SOME PATCHY GROUND FOG GIVEN IMPRESSIVE OVERNIGHT COOLDOWN.
TODAY: RIDGE AXIS WILL BE PRETTY MUCH OVERHEAD TO START THE
DAY...GRADUALLY SHIFTING EAST TO A POSITION OVER LAKE HURON
TOWARDS EVENING. THERE/S A RELATIVE LACK OF MOISTURE THROUGH THE
COLUMN TO START THE DAY WITH PWATS SUB 0.25" /A LITTLE BELOW
SEASONAL NORMS FOR LATE MARCH/ WITH VALUES INCREASING DURING THE DAY
AS A CHUNK OF PACIFIC MOISTURE /SEEN NOW AS A PLUME OF DEEP MOISTURE
ACROSS THE NORTHWESTERN QUARTER OF THE COUNTRY/ RIDES EAST. WHILE
THIS COULD MANIFEST ITSELF AS SOME HIGH CLOUDS FOR THE NORTHERN HALF
OF THE CWA /ESP FOR THE SECOND HALF OF THE DAY/...THE LACK OF LLEVEL
MOISTENING BENEATH BUILDING MID LEVEL HEIGHTS SUGGESTS NO REAL
POTENTIAL FOR CU DEVELOPMENT. THUS...EXPECT ABUNDANT SUNSHINE FOR
THE AREA WITH NO SENSIBLE WEATHER CONCERNS.
TEMPERATURES /CONFIDENCE: HIGH/:
TRAJECTORY ANALYSIS PLACES THIS AFTERNOON/S AIRMASS OVER SOUTHERN
MINNESOTA 24 HOURS PREVIOUS WITH T9S SURGING TO 0-3C BY LATE
AFTERNOON UNDER STRONG WARM ADVECTION. WITH BUILDING HEIGHTS AND
NEARBY RIDGE AXIS...MIXING ISN/T GOING TO BE TOO STRONG. LOOKING
BACK TO MINNESOTA...AREAS THAT WERE UNABLE TO MIX DEEPLY REACHED THE
LOWER 40S...WITH UPPER 40S FURTHER WEST WHERE MECHANICAL MIXING
COMBINED WITH WARMER TEMPS ALOFT TO BOOST SURFACE TEMPS. EXPECT
THAT WE/LL BE CLOSER TO THE FORMER TODAY...AND EXPECT HIGHS IN THE
40-45 DEGREE RANGE. AMAZINGLY...THAT WILL PUT US JUST ABOUT WHERE
WE SHOULD BE FOR THE END OF MARCH.
AS MENTIONED BY THE PREVIOUS DAYSHIFT...LIGHT FLOW REGIME AND
SOMEWHAT WARMER TEMPERATURES SHOULD ALLOW FOR SOME LAKE BREEZE
DEVELOPMENT...KEEPING HIGHS LOCALLY COOLER ALONG THE LAKE HURON
COAST.
TONIGHT: RIDGE CONTINUES TO PUSH EAST OF THE GREAT LAKES
REGION...WITH NORTHERN STREAM COLD FRONT STALLING NEAR LAKE SUPERIOR
AS LOW PRESSURE ALONG THE EAST SLOPES OF THE ROCKIES BEGINS TO
DEPART AND HEAD NORTHEAST. MOISTURE CONTINUES TO SLOWLY
INCREASE...BUT PRIMARILY AT UPPER LEVELS WITH TOP-DOWN SATURATION
LIKELY ONLY YIELDING AN INCREASE IN UPPER LEVEL CLOUDS THROUGH THE
OVERNIGHT. GRADIENT STRENGTHENS THROUGH THE NIGHT...WITH MOST
LOCATIONS RE-COUPLING DURING THE OVERNIGHT. SEE NO REPEAT OF ANY
FOG GIVEN BETTER LLEVEL MIXING AND CONTINUED DRY LLEVEL CONDITIONS.
TEMPERATURES /CONFIDENCE: MODERATE-HIGH/:
TEMPERATURES WILL BE A LITTLE COMPLEX WITH EVENING MCLEAR SKIES AND
DECOUPLING LIKELY TO GIVE WAY TO INCREASED MIXING AS THE NIGHT GOES
ON. THIS WILL YIELD LOWS COLDEST OVER NORTHEAST LOWER WITH LOWS
LIKELY TO DIP TO AROUND 20 /AND PERHAPS A TAD BELOW THIS/...WITH
TEMPS OVER NORTHWEST LOWER STRUGGLING TO FALL MUCH BELOW THE
FREEZING MARK.
&&
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 309 AM EDT SUN MAR 30 2014
...REAL SPRING "WARMTH" GIVES WAY TO BELOW NORMAL TEMPERATURES (GO
FIGURE)...
HIGH IMPACT WEATHER POTENTIAL: WATCHING WINTRY PRECIP THREAT LATER
IN THE WEEK.
OVERVIEW: PATTERN REMAINS AN AGITATED ONE...WITH EXTENDED AMPED
PACIFIC REGIME OVER THE CONUS TUCKED NICELY ON SOUTH SIDE OF WELL
DEVELOPED NORTH CANADA COLD CORE GYRE. PACIFIC PATTERN CONTINUES TO
WIN OUT OVER NORTHERN MICHIGAN...WITH STEADY RETREAT OF OVERHEAD
COLD AIRMASS AS AGGRESSIVE UPSTREAM WARMING BEGINS. 00Z RAOB/HIGH
RES RAP GUIDANCE CONFIRMS SUCH...SHOWING H8 TEMPERATURES SPIKING
INTO THE TEENS (THAT`S ABOVE ZERO FOLKS!) ACROSS THE HIGH
PLAINS...WITH ABOVE ZERO H8 AIR ALREADY ADVANCING TO THE MISSISSIPPI
RIVER. EXPECTED RATHER SUBSTANTIAL UPPER MISSISSIPPI VALLEY LOW
PRESSURE DEVELOPMENT EARLY THIS WORK WEEK WILL ONLY HELP THE
NORTHERN LAKES WARMING CAUSE...WITH MUCH OF THE AREA TO FALL
SQUARELY IN THE WARM SECTOR OF THIS SYSTEM AS IT TRACKS TO OUR
NORTHWEST. UNFORTUNATELY...COOL AIR WILL BE FORCED SOUTH ON ITS
BACKSIDE...ONCE AGAIN DROPPING TEMPERATURES TO BELOW NORMAL LEVELS
AS WE HEAD THROUGH THE MID AND AND PORTIONS OF NEXT WEEK. PACIFIC
WAVE TRAIN REMAINS...AT LEAST SETTING UP SOME POTENTIAL FOR BOUTS OF
MORE WINTRY WEATHER HEADING INTO THURSDAY AND FRIDAY. OH...THE
JOY!
PRIMARY FORECAST CONCERNS/CHALLENGES: PLENTY! TEMPERATURE TRENDS
THROUGHOUT...PRECIP TIMING/AND EVENTUAL TYPE...HEADING THROUGH NEXT
WORK WEEK.
DETAILS: JUST HOW WARM TO GO ON MONDAY? ABOUT TEXTBOOK END OF
MARCH/BEGINNING OF APRIL SPRING STORM WILL BE UNDERGOING FULL
DEVELOPMENT ACROSS THE CENTRAL PLAINS EARLY MONDAY...EXPECTED TO
PASS SOMEWHERE VICINITY CENTRAL/WESTERN UPPER MICHIGAN TUESDAY.
STRONG DOWNSTREAM OFF THE DECK WAA EXPECTED...WITH NOW MULTI-DAY
PROGS SUPPORTING H8 READINGS SPIKING TO NEAR 10C BY LATER MONDAY
OVER NORTHERN MICHIGAN. WITH ELEVATED WARM FRONT ALREADY NORTH OF
THE AREA...AND CORE OF MID LEVEL DYNAMICS WELL OFF TO OUR
WEST...WOULD EXPECT PLENTY OF SUNSHINE TO FURTHER KICK THE WARMING
INTO OVERDRIVE. INCREASINGLY DEEP MIXED LAYER/FORCED MECHANICAL
MIXING PER INCREASING WINDS SHOULD ALLOW SURFACE TEMPERATURES TO
RESPOND ACCORDINGLY...AND REALLY LIKE INHERITED HIGHS WILL INTO THE
50S/NEAR 60 OVER NORTHERN LOWER MICHIGAN. SOUTHEAST LOW LEVEL FLOW
WILL KEEP NORTHEAST LOWER AND EASTERN UPPER MICHIGAN SEVERAL DEGREES
COOLER. MILD AIR CONTINUES INTO MONDAY NIGHT AS SOUTH FLOW
REMAINS...AND FEEL SOME AREAS MAY FAIL TO FALL OUT OF THE 40S. DRY
WEATHER GIVES WAY TO INCREASING SHOWER CHANCES MONDAY NIGHT AS
OCCLUDED FRONT INTERACTS WITH NARROW BAND OF ENHANCED DEEP LAYER
MOISTURE. STRONGEST AND DEEPEST DYNAMICS REMAIN TO OUR
NORTHWEST...WHERE HEAVIEST AND STEADIEST PRECIPITATION SHALL RESIDE.
BACK TO 2014 SPRING NORMALCY QUICKLY ON TUESDAY AS SURGE OF COLDER
AIR FOLLOWS PASSAGE OF OCCLUDED FRONT. MORNING HIGH TEMPERATURES IN
THE 30S AND 40S WILL SLOWLY FALL THROUGH THE AFTERNOON ON GUSTY
SOUTHWEST TO WEST WINDS. LIGHT RAIN/SNOW SHOWERS TRANSITION TO
MAINLY SNOW AS COLD AIR DEEPENS AND SYSTEM BACKSIDE MOISTURE
REMAINS. JUST MINIMAL...IF ANY...ACCUMULATION IS EXPECTED.
UNCERTAINTY THE NAME OF THE GAME HEADING INTO THE MID AND END
PORTIONS OF THE WEEK. QUESTIONS ARE MANY CONCERNING NEXT WAVE
EXPECTED TO EJECT OUT OF THE INTERMOUNTAIN WEST. INTERACTION BETWEEN
SOUTHERN CANADA HIGH/ASSOCIATED DRY AIR FEED AND WHAT SHOULD BE
RATHER VIGOROUS MID LEVEL WAVE LEADING TO RATHER SIGNIFICANT
DISCREPANCIES AMONGST MID RANGE GUIDANCE. ECMWF REMAINS MOST
ROCK-STEADY...SUGGESTING A MORE AMPED AND FURTHER NORTH SOLUTION
WITH LOW PRESSURE MOVING DIRECTLY ACROSS THE GREAT LAKES TO END THE
WORK WEEK. OTHER GUIDANCE STARTING TO FALL IN LINE WITH THIS MORE
NORTH/AMPED SOLUTION...ALTHOUGH HONESTLY...THIS DOES LITTLE TO
INCREASE CONFIDENCE AS A MORE SOUTH DISPLACED SYSTEM IS FULLY
PLAUSIBLE GIVEN EXPECTED SET-UP AND POTENTIAL FOR A STRONGER
CANADIAN HIGH. TEMPERATURE PROFILE REMAINS MARGINALLY SUPPORTIVE OF
A MIXED PRECIP EVENT IF FURTHER NORTH SOLUTIONS VERIFY. SET-UP ALSO
HAS SOME INTRIGUING FREEZING RAIN POSSIBILITIES...WITH POTENTIAL FOR
MAINTENANCE OF DRY AND COLD EAST FLOW TO MAINTAIN SUB-FREEZING
SURFACE TEMPERATURES...ALL THE WHILE ELEVATED WARM NOSE DEEPENS. OF
COURSE...MUCH TOO FAR OUT TO SHOW SUCH SPECIFICS...ESPECIALLY
CONSIDERING UNCERTAINTY IF SYSTEM WILL EVEN DIRECTLY AFFECT OUR
AREA. LITTLE CHOICE BUT TO RUN WITH A GENERIC RAIN/SNOW CHANCE
WORDING FOR NOW...WITH PLENTY OF TIME TO FINE-TUNE DETAILS IN
COMING DAYS. WHILE EXCEPTIONALLY COLD AIR NOW LOOKS LIKE A THING OF
THE PAST...OVERALL TRENDS FAVOR BELOW NORMAL TEMPERATURES WEDNESDAY
THROUGH NEXT WEEKEND...WITH HIGHS MOSTLY IN THE 30S AND LOWER
40S/OVERNIGHT LOWS IN THE 20S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 116 AM EDT SUN MAR 30 2014
...QUIET TODAY WITH LLWS CONCERNS TONIGHT...
SUMMARY: HIGH PRESSURE OVERHEAD WILL GRADUALLY SHIFT EAST THROUGH
THE TAF PERIOD...WITH VERY QUIET CONDITIONS EXPECTED.
RESTRICTIONS: VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD.
OVERNIGHT DEWPOINT DEPRESSIONS HAVE REMAINED SUBSTANTIAL AND
THEREFORE HAVE REMOVED FOG POTENTIAL FOR THE REMAINDER OF THE
OVERNIGHT.
SCATTERED HIGH CLOUDS EXPECTED TODAY...WITH THESE CLOUDS
THICKENING SOME TONIGHT.
ATMOSPHERE WILL MOISTEN THROUGH TODAY AND TONIGHT...BUT
STRENGTHENING MIXING AS WELL AS INCREASING OVERNIGHT CLOUD COVER
SHOULD PRECLUDE SIGNIFICANT FOG POTENTIAL SUNDAY NIGHT.
WINDS: CALM-LIGHT/VARIABLE WINDS THROUGH DAYBREAK WILL BE
LIGHT/VARIABLE THROUGH THE MORNING...BEFORE SOUTH/SOUTHEAST WINDS
5-10KTS DEVELOP THIS AFTERNOON FOR PLN/TVC/MBL...WITH MORE EASTERLY
LAKE BREEZE FLOW 10 KTS AT APN. WINDS LIKELY TO GO LIGHT/VARIABLE
AT APN THROUGH TONIGHT AND FOR SOME OF THE EVENING AT PLN/TVC/MBL...
WITH SOUTHEAST WINDS AROUND 5KTS DEVELOPING AFTER MIDNIGHT.
LLWS: POTENTIAL EXISTS FOR LLWS CONCERNS PARTICULARLY OVER NORTHWEST
LOWER TONIGHT AS SOUTH TO SOUTHWESTERLY LOW LEVEL JET STRENGTHENS
DURING THE EVENING HOURS ABOVE WHAT WILL LIKELY BE LIGHT
SOUTHEASTERLY WINDS NEAR THE SURFACE. WILL INCLUDE LLWS MENTION AT
MBL/TVC WHERE CONFIDENCE IS HIGHEST AT THIS TIME.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
SYNOPSIS...MSB
SHORT TERM...ARNOTT
LONG TERM...MSB
AVIATION...ARNOTT
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1139 PM CDT Sat Mar 29 2014
.UPDATE:
Issued at 919 PM CDT Sat Mar 29 2014
Area of MVFR stratus has continued to dissipate and is now
confined to portions of south-central Illinois. Expect this area
to completely erode by 0600 UTC with mainly clear skies for most
of the rest of tonight. Exception would be over western areas as
cirrus tries to advect in from the west/northwest.
Surface temperatures over the past two hours have dropped very
rapidly over most of the region where combination of clear
skies/light winds exist. Lowered minimum temperatures a few
degrees over many areas using a blend of the 0000 UTC RAP which
was capturing this rapid drop fairly well as well as the previous
forecast. Other concern overnight will be fog potential and patchy
fog with restricted visibilities below 3 miles still looks on
track though certainly could not rule out some denser fog
especially in river valleys and other low-lying elevations.
Gosselin
&&
.SHORT TERM: (Through Late Tonight)
Issued at 320 PM CDT Sat Mar 29 2014
Pesky stratus seems to be both clearing and eroding at a snails
pace this afternoon and has a done number on the temperatures.
Present indications based on satellite trends and the RAP which
has handled the low clouds best, is that areas generally along and
east of the MS River will see clouds into early evening with
clearing from mid-late evening. Otherwise the expansive NE-SW high
pressure system currently extending from WI into TX will slide
east across the region tonight with the axis centered thru SE MO
and southern IL at 12z. The slow clearing trend of the clouds
along with light winds overnight across the SE third of the CWA
has prompted me to add a mention of fog overnight.
Glass
.LONG TERM: (Sunday through Next Saturday)
Issued at 320 PM CDT Sat Mar 29 2014
It finally looks like the warm-up will commence on Sunday. Heights
aloft that begin rising tonight in the wake of the departing upper
trof, will continue to rise on Sunday while the surface high
retreats and low level southerly flow and warm advection get
underway. There should be no low clouds to deal with a just some
thin high clouds filtering across the region. The current forecast
leveraging the warmer temperatures looks right on the mark and no
changes were made. The warmer temps combined with low afternoon
RH values and increasing southerly winds support an elevated fire
danger threat across central and east central MO, which will be
highlighted in the HWO.
Continued southerly low level flow on Sunday night will lead to
"milder" min temperatures and a slow return in low level moisture.
The aforementioned expansive surface high and its southern extent
will initially have a profounded effect on trajectories and delay
quality moisture return. However mid level moisture won`t be an
issue and this along with the eastern edge of steeper mid level
lapse rates spreads into central MO just before daybreak on
Monday. These ingredients along with the leading edge of forcing
aloft associated with an upstream trof, suggests potential for
some high-based scattered showers/thunderstorms and hence have
added some slight chance pops.
The week ahead looks especially active. The migratory upper trof
partly responsible for the slight chance pops late Sunday night
will move across the region Monday afternoon and early evening
spreading height falls and cooling aloft along with a plume of
steep mid level lapse rates. This combined with a gradual increase
in low level moisture and forcing should be sufficient for
scattered elevated showers/thunderstorms within the warm sector, moving
through central and northeast MO during the morning gradually
dwindling in coverage during the afternoon as they move east. By
the time the cold front moves through the area Monday night,
forcing aloft appears to have outrun the front and boundary layer
moisture and hence instability are quite weak. I suspect anything
that might be able to develop with be quite spotty and just have a
slight chance pop.
The most active period will be late Tuesday night into Thursday.
The front that moves through Monday night will move back north
and waver across the region. The warm sector air mass south of
this boundary will become quite unstable thanks to continued
northward return of quality Gulf moisture and the presence of
steep mid level lapse rates, and with a strong low level jet
evolving there will be good elevated instability and forcing north
this boundary. The models differ quite a bit on the position of
the next formidable migratory upper trof and the position of
attendant surface low(s) and this boundary. While all the guidance
supports a stormy period, the more northern position which has
been consistently advertised by the ECMWF would lead to a much
more volatile set-up.
Glass
&&
.AVIATION: (For the 06z TAFs through 06z Sunday Night)
Issued at 1131 PM CDT Sat Mar 29 2014
Light fog has developed across the region, especially near and
east of the Mississippi River (where daytime mixing was limited by
persistent stratus) and in river valleys. Light fog will begin to
lift and dissipate during the morning hours after winds start to
increase in response to the tightening pressure gradient. LLWS is
possible towards the end of the valid TAF period based on model
depictions of strong winds around 1200 ft.
Specifics for KSTL: Light fog is expected tonight, but
visibilities should remain in the MVFR to VFR range. Winds will
increase during the morning due to the tightening pressure
gradient. LLWS is possible towards the end of the valid TAF period
based on model depictions of strong winds around 1200 ft.
Kanofsky
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
359 AM CDT SUN MAR 30 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 359 AM CDT SUN MAR 30 2014
ANOTHER WARM DRY SURGE OF AIR MOVES OFF THE CNTL ROCKIES TODAY. THE
TEMPERATURE FORECAST FOLLOWS THE UPPER MIDDLE OF THE 13 MODEL SUPER
ENSEMBLE FOR HIGHS IN THE 70S TO NEAR 80. A STATIONARY FRONT IS
EXPECTED TO DEVELOP ALONG THE SD BORDER CAUSING WINDS TO BACK ACROSS
THE NORTH KEEPING HIGHS NEAR 70. WE ALSO SEE A FAIRLY SOLID CIRRUS
SHIELD DEVELOPING OFF THE LARAMIE AND FRONT RANGE LIMITING HEATING
SOMEWHAT. SOUTH WINDS INCREASE TO 10 TO 20 MPH WITH GUSTS TO 25 MPH
ACROSS MOST OF THE FCST AREA.
FOR TONIGHT...SFC LOW PRESSURE WILL TRACK THROUGH THE CENTER OF THE
FCST AREA AND WINDS BECOME NORTHWEST BEHIND THE SFC LOW ACROSS WRN
NEB. ISOLATED THUNDERSTORMS ARE POSSIBLE THIS EVENING AND OVERNIGHT
IN RESPONSE TO A LOW LEVEL JET AND COOLING/FALLING HEIGHTS ALOFT.
THE NEW MODEL CONSENSUS BRINGS A SHARP 500 MB TROF INTO ERN WY AT
06Z WHICH CLOSES OFF ACROSS NW NEB BY 12Z. THERE ARE SIGNS OF THE
HEIGHTS BACKING IN ALOFT ACROSS WRN SD AT THIS TIME WHICH IS
TROUBLING SINCE THE LATEST ENSEMBLE SOLN IS TAKING THE UPPER LEVEL
ENERGY ACROSS THE TETONS AND BIG HORN RANGES BUT THEN IT DROPPING
SOUTH OF THE BLACK HILLS. THIS MORE SRN TRACK RAISES THE POP ACROSS
NWRN NEB BETWEEN 06Z AND 12Z. THE NAM AND GEM REGIONAL THEN BRING
THE RAIN SNOW LINE INTO NRN SHERIDAN COUNTY BETWEEN 09Z AND 12Z.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 359 AM CDT SUN MAR 30 2014
ATTENTION IN THE EXTENDED PERIODS CENTER ON PRECIPITATION
CHANCES...MAINLY THE POTENTIAL OF TWO SIGNIFICANT LATE WINTER TYPE
STORMS THAT MAY BRING ACCUMULATING SNOW TO PORTIONS OF THE CWA.
THE FIRST SYSTEM WILL BE ONGOING ACROSS OUR NORTHERN ZONES BY 12Z
MONDAY. LOW PRESSURE AND ASSOCIATED PV ANOMALY WILL CROSS FROM THE
CENTRAL ROCKIES NORTHEAST OUT ONTO PLAINS...DRAGGING MODIFIED
ARCTIC AIR SOUTH FROM CANADA ACROSS THE NORTHERN/CENTRAL PLAINS.
MEDIUM RANGE MODELS HAVE GENERALLY COME INTO FAIR AGREEMENT WITH
THE TRACK OF THE SURFACE CYCLONE...BUT INTENSITY/TIMING
DIFFERENCES STILL EXIST. ATTM GENERALLY FAVOR THE GEM SOLUTION IN
WHICH THE TRACK FAVORS STRONG FRONTOGENETIC FORCING MAINLY NORTH
OF THE CWA. THAT BEING SAID...THERE/S STILL STRONG AGREEMENT THAT
SNOW WILL WRAP AROUND THE LOW BACK ACROSS NORTHERN PORTIONS OF THE
CWA. ATTM SNOW ACCUMULATIONS LOOK FAVORABLE FOR NORTHWESTERN
NEBRASKA EARLY MONDAY...THEN TRANSITION EAST THROUGH THE DAY. THE
PTYPE FORECAST IS STILL PROBLEMATIC. THE GEM SOLUTION IS WARMER
WITHIN THE WARM SECTOR AS THE MODEL LIFTS THE LOW FURTHER NORTH
THAN EAST...CHANGEOVER TO ALL SNOW MAY NOT OCCUR FOR OUR FAR
EASTERN ZONES UNTIL MID-LATE AFTERNOON. WHERE THE CHANGE OVER DOES
OCCUR EARLY...IMPACTS TO TRAVEL WOULD BE EXPECTED...ESPECIALLY
GIVEN WIND GUSTS IN EXCESS 45 MPH. ATTM ALONG AND NORTH OF HIGHWAY
20 IN CHERRY AND SHERIDAN COUNTIES IS WHERE THE GREATEST
CONFIDENCE IN SEEING THE EARLY CHANGEOVER AND ACCUMULATING SNOW.
FOR THIS...WILL ISSUE A WINTER WEATHER ADVISORY WITH THIS FORECAST
PACKAGE FOR THE TWO COUNTIES LISTED AS IMPACTS TO
KVTN...RANCHING...HIGHWAY 20 AND THE POPULOUS CENTERED ALONG THE
HIGHWAY ARE ANTICIPATED TO BE SIGNIFICANT. NOTE...IT COULD VERY
WELL BE THAT SOUTHERN PORTIONS OF THESE TWO COUNTIES NOT SEE MUCH
IF ANY ACCUMULATING SNOW WITH THIS SYSTEM WHILE THE FAR NORTH
EXPERIENCES NEAR BLIZZARD CONDITIONS AND UP TO 4 INCHES OF SNOW. A
HIGH END WIND ADVISORY IS ANTICIPATED MONDAY AS WELL ACROSS THE
ENTIRE CWA. A STACKED PRESSURE GRADIENT WITH PRESSURE RISES ON THE
ORDER OF UP TO 3 MB PER HOUR WILL LEAD TO NEAR HIGH WIND WARNING
GUST CRITERIA. WILL LET THE DAY SHIFT FINE TUNE THE SPECIFICS.
LASTLY...NEGATIVE LI/S ACROSS NORTH CENTRAL/NORTHERN NEBRASKA
EARLY MONDAY WITH WEAK INSTABILITY ALOFT MAY YIELD A FEW EMBEDDED
CONVECTIVE SHOWERS...WHETHER SNOW OR RAIN. NO MENTION OF THUNDER
WAS INCLUDED BEYOND 12Z MONDAY...BUT MAY NEED TO BE LOOKED AT
FURTHER.
LOW AMPLITUDE TRANSITORY RIDGING BUILDS ATOP THE PLAINS ON TUESDAY
WITH A RETURN TO AN ACTIVE PATTERN BY MIDWEEK. SOUTHWESTERLY FLOW IN
THE UPPER LEVELS WILL PREVAIL AS THE NEXT LONGWAVE TROUGH OF
INTEREST STARTS TO BUILD ACROSS THE DESERT SOUTHWEST WEDNESDAY.
SLIGHT OPPORTUNITIES FOR QPF ALSO ARRIVE ON WEDNESDAY WITH THE
APPROACH OF FAVORABLE UPPER LEVEL JET SUPPORT AND A SW DISTURBANCE.
HOWEVER BETTER CHANCES ARRIVE LATE IN THE WEEK AS THE TROUGH EJECTS
NORTHEAST FROM THE 4 CORNERS ONTO THE CENTRAL PLAINS. THERE REMAINS
LARGE DISCREPANCIES ON HOW THE MODELS HANDLE THIS SYSTEM...WITH THE
ECMWF NOW TAKING ON A NEGATIVE TILT AND A FAVORABLE TRACK OF THE H5
LOW FOR SNOW ACCUMULATION...POSSIBLY SIGNIFICANT ACROSS THE WEST CENTRAL
SANDHILLS. THE GFS REMAINS OPEN AND PROGRESSIVE WITH FAR LESS
IMPACTS. DUE TO THE MYRIAD OF WEATHER CURRENTLY GOING ON RIGHT
NOW...FELT IT WAS BEST TO NOT VARY FROM A GENERAL MODEL BLEND WITH
THIS LATE WEEK SYSTEM.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1229 AM CDT SUN MAR 30 2014
VFR CONDITIONS WILL CONTINUE ACROSS WESTERN AND NORTH CENTRAL
NEBRASKA THROUGH THE TAF PERIOD. ON SUNDAY...A WARM FRONT WILL
DEVELOP NEAR OR JUST NORTH OF THE KVTN TERMINAL. THEREFORE PREVAILING
SOUTHERLY WINDS 12G18KT CAN BE EXPECTED AFTER 18Z. HIGH CLOUDINESS
WILL THICKEN AND LOWER LATER SUNDAY AFTERNOON FOR BOTH
TERMINALS...BUT VFR WILL BE MAINTAINED.
&&
.FIRE WEATHER...
ISSUED AT 359 AM CDT SUN MAR 30 2014
RED FLAG CONDITIONS ARE EXPECTED ACROSS THE ERN PANHANDLE...CENTRAL
SANDHILLS...FRENCHMAN BASIN AND THE LOESS PLAINS. THE FORECAST IS A
LOW END RED FLAG WARNING AS THE RAP SHOWS WINDS AT 700MB WEAKENING
THIS AFTERNOON WHILE THE NAM ACTUALLY STRENGTHENS THEM. THE FORECAST
FOLLOWS A BLEND OF THE GUIDANCE FROM THE RAP13...HRRR...NAMDNG AND
AVN MOS MODELS FOR SOUTH WINDS OF 10 TO 20 MPH AND GUSTS TO 25 MPH.
DEWPOINTS SHOULD FALL INTO THE TEENS...BUT ABOUT 5 DEGREES F HIGHER
THAN SATURDAY.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 1 PM CDT /NOON MDT/ THIS AFTERNOON TO 9 PM
CDT /8 PM MDT/ THIS EVENING FOR NEZ204-206-210-219.
WINTER WEATHER ADVISORY FROM 4 AM CDT /3 AM MDT/ TO 7 PM CDT /6
PM MDT/ MONDAY FOR NEZ004-005-094.
&&
$$
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...CDC
FIRE WEATHER...CDC
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
511 AM EDT SUN MAR 30 2014
.SYNOPSIS...
A COMPLEX LOW PRESSURE SYSTEM WILL CONTINUE TO BRING MIXED
PRECIPITATION TO THE NORTH COUNTRY THIS MORNING...AND TAPER OFF
TO DRIZZLE AND FREEZING DRIZZLE THIS AFTERNOON. PORTIONS OF
CENTRAL AND SOUTHERN VERMONT WILL CONTINUE TO SEE LIGHT ICE
ACCUMULATIONS TONIGHT INTO MONDAY MORNING AS THE LOW TRACKS OFF
THE EASTERN SEABOARD...WITH DRIER CONDITIONS RETURNING TO THE
ENTIRE REGION BY MONDAY AFTERNOON.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 510 AM EDT SUNDAY...FORECAST PLAYING OUT FAIRLY WELL WITH A
MYRIAD OF PRECIPITATION TYPES EXPERIENCED ACROSS THE NORTH COUNTRY
OVERNIGHT ASSOCIATED WITH LOW PRESSURE MOVING EASTWARD THROUGH THE
MID-ATLANTIC STATES. ACROSS VERMONT...PRECIP STARTED OUT AS A MIX
OF SNOW...RAIN AND FREEZING RAIN BUT AS OF 5 AM SEEING MAINLY A
MIX OF RAIN AND SNOW. MEANWHILE...ACROSS NORTHERN NEW YORK SNOW
HAS BEEN THE PREDOMINANT PTYPE WITH SEVERAL INCHES OF SNOW
ACCUMULATIONS BEING REPORTED. MODEL OF CHOICE OVERNIGHT HAS BEEN
THE RAP WHICH CONTINUES TO HANDLE THE VERTICAL THERMAL STRUCTURE
VERY WELL SHOWING +0C LAYER AT 850MB SHIFTING NORTHWARD
THROUGH VT WHILE FROM THE SURFACE-925MB REMAINED NEARLY
ISOTHERMAL. AS THE BULK OF PRECIP SHIFTS NORTHWARD OUT OF THE
REGION THIS MORNING...WE`RE LEFT WITH SUPER-SATURATED LOW LEVELS
AND ZERO ICE IN THE FAVORED SNOW GROWTH REGION ALOFT ALONG WITH
COOLING MID LEVELS. THIS WILL SUPPORT A TRANSITION TO DRIZZLE
AND/OR FREEZING DRIZZLE ACROSS MOST OF THE AREA...THOUGH SOME
LINGERING SNOW SHOWERS WILL BE POSSIBLE ACROSS THE SAINT LAWRENCE
VALLEY DUE TO COLDER PROFILES. TEMPS WILL BASICALLY GO NOWHERE
TODAY UNDER THICK CLOUD COVER AND NORTH TO NORTHEASTERLY
FLOW...HOLDING STEADY IN THE LOW/MID 30S TO UPPER 20S AREA-WIDE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
AS OF 510 AM EDT SUNDAY...FOR TONIGHT INTO MONDAY...MODELS HAVE
COME INTO BETTER AGREEMENT IN REGARDS TO ANOTHER ROUND OF MIXED
PRECIPITATION ACROSS CENTRAL AND SOUTHERN VERMONT AS ADDITIONAL
SHORTWAVE ENERGY ROTATES AROUND THE SLOWLY DEPARTING UPPER LOW.
LOW LEVEL TEMPERATURES COOL ACROSS THE AREA OVERNIGHT WHILE TEMPS
AT MID-LEVELS REMAIN ABOVE FREEZING SETTING THE STAGE FOR AREAS OF
FREEZING DRIZZLE/RAIN THROUGH MONDAY MORNING. GREATEST CHANCES OF
ICE ACCUMULATION WILL BE OVER CENTRAL AND SOUTHEASTERN ZONES DUE
TO THE PROXIMITY WITH UPPER LOW....AND WINTER WX ADVISORIES HAVE
BEEN EXTENDED FOR A LIGHT GLAZE OF UP TO A TENTH OF AN INCH LIKELY.
LATE MONDAY INTO MONDAY NIGHT DRIER CONDITIONS RETURN TO THE
REGION AS DEEP LAYER RIDGING BUILDS EASTWARD FROM THE GREAT LAKES
INTO THE NORTHEAST. SKIES CLEAR FROM WEST TO EAST WITH ANOTHER
NIGHT OF BELOW NORMAL TEMPS EXPECTED IN THE TEENS TO 20S. SUNNY
CONDITIONS ARE EXPECTED FOR TUESDAY UNDER THE RIDGE WITH
TEMPERATURES REBOUNDING INTO THE 40S IN THE AFTERNOON.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 340 AM EDT SUNDAY...SEASONABLE EARLY SPRING TEMPERATURES
ALONG WITH PERIODIC CHANCES OF RAIN OR SNOW SHOWERS WILL BE THE
RULE DURING THE MIDDLE TO LATER PORTIONS OF NEXT WEEK. BEST SHOT
AT PCPN WILL OCCUR TUE NT/WED MORNING...THEN AGAIN BY NEXT
WEEKEND. THE MID-WEEK SYSTEM WILL BE RATHER WEAK AS NORTHERN
STREAM SHORTWAVE ENERGY PASSES TO OUR NORTH. THUS PCPN SHOULD BE
LIGHT AT BEST WITH MANY AREAS REMAINING DRY...ESP ACROSS OUR
SOUTHERN COUNTIES. THE SYSTEM FOR NEXT WEEKEND A LITTLE MORE
ROBUST SO A BETTER SHOT AREA WIDE FOR RAIN/SNOW SHOWERS. IN
BETWEEN (WED AFTERNOON THROUGH FRIDAY MORNING) GENERALLY HIGH
PRESSURE WITH CLEAR/PTLY CLOUDY SKIES AND DRY WEATHER EXPECTED.
HIGHS GENERALLY IN THE 40S THROUGH THE PERIOD WITH A SPOT 50 HERE
AND THERE POSSIBLE WED-FRI. OVERNIGHT LOWS GENERALLY FROM 25 TO 35
THOUGH MAINLY 20S WED NT/THU NT WITH AFOREMENTIONED HIGH PRESSURE
IN CONTROL AND BETTER SHOT AT PARTIALLY CLEAR SKIES.
&&
.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
THROUGH 06Z MONDAY...WIDESPREAD MVFR/IFR ACROSS THE REGION IN
MODERATE TO HEAVY MIXED PCPN AND/OR RAIN AS LOW PRESSURE ALONG THE
NORTHERN MID-ATLANTIC COAST DRAWS COPIOUS MOISTURE NORTHWARD.
TERMINAL SPECIFIC DETAILS BELOW...
KBTV...MIX OF RAIN/FZRA THROUGH 12Z...THEN MAINLY LT RAIN TAPERING
TO SHOWERS AFTER 18Z. VFR/MVFR FLYING CONDS EXPECTED THROUGH THE
PERIOD W/BRIEF IFR POSSIBLE. WINDS NORTH/NORTHWESTERLY 7-15 KTS.
KMPV...MIX OF RAIN/FZRA THROUGH 12Z...THEN MAINLY LT RAIN TAPERING
TO SHOWERS AFTER 18Z. IFR/MVFR CONDS EXPECTED THROUGH THE PERIOD.
WINDS LGT AND VRB THROUGH 12Z...THEN NORTH/NORTHWESTERLY 6-12 KTS
THEREAFTER.
KRUT...PERIODS OF LIGHT RAIN...TAPERING TO SHOWERS BY 18Z. MIX OF
VFR/MVFR FLYING CONDS EXPECTED THROUGH THE PERIOD. WINDS EASTERLY
8 TO 15 KTS WITH GUSTS TO 20 KTS...TRENDING NORTH TO NORTHEASTERLY
AFTER 12Z.
KPBG...LIGHT TO MODERATE SNOW THROUGH 10-12Z...THEN MIXING WITH
SLEET. IFR LIKELY THROUGH 15Z...TRENDING MVFR THEREAFTER. SOME MIX
WITH RAIN ALSO POSSIBLE AFTER 16Z BEFORE PCPN TAPERS TO SHOWERS.
WINDS NORTHERLY 10-18 KTS AND TRENDING GUSTY TO 25 KTS THIS
AFTERNOON.
KMSS...LIGHT TO MODERATE SNOW EXPECTED THROUGH MUCH OF THE
PERIOD...TAPERING TO SCT SHSN AFTER 00Z MONDAY. IFR FLYING CONDS
EXPECTED THROUGH AFTERNOON...TRENDING MVFR AFTER 18Z. WINDS
NORTHEASTERLY 15 TO 22 KTS WITH GUSTS TO 30 KTS EXPECTED...ABATING
SLIGHTLY TOWARD EVENING. CONSIDERABLE BLSN LIKELY.
KSLK...LIGHT/MODERATE SNOW EXPECTED WITH SOME MIX OF FZRA/PL
POSSIBLE...TAPERING TO SCT SHSN/SHRA AFTER 18Z. WIDESPREAD
IFR...TRENDING MVFR AFTER 18Z. WINDS NORTHEASTERLY 6-12
KTS...OCCNL GUSTY TO 20KTS THIS AFTERNOON.
OUTLOOK 06Z MONDAY THROUGH THURSDAY...
06Z MONDAY TO 18Z MONDAY...TRENDING SLOWLY TO VFR FROM WEST TO
EAST AS LIGHT RAIN/SNOW TAPERS OFF. BEST SHOT AT CONTINUED LIGHT
PCPN AND MVFR/IFR AT ERN TERMINALS OF KMPV/KRUT. AGAIN...HIGHEST
CONFIDENCE OF BETTER FLIGHT CONDS AT NRN NY TERMINALS WITH
CONTINUED UNCERTAINTY FURTHER EAST.
18Z MONDAY THROUGH 00Z WEDNESDAY...VFR WITH HIGH PRESSURE.
00Z WEDNESDAY THROUGH 00Z THURSDAY...VFR ALTHOUGH SOME BRIEF
PERIODS OF MVFR POSSIBLE IN SCATTERED RAIN/SNOW SHOWERS AS COLD
FRONT CROSSES REGION.
00Z THURSDAY ONWARD...VFR W/MVFR PSBL LATE THURSDAY AS WARM FRONT
APPROACHES FROM SW...BRINGING PRECIP SOUTH TO NORTH.
&&
.HYDROLOGY...
AS OF 340 AM EDT SUNDAY...COMPLEX HYDRO SITUATION WILL DEVELOP
ACROSS OUR SOUTHERN WATERSHEDS TODAY WHERE A SOAKING RAINFALL ON
THE ORDER OF 1-1.75 INCHES WILL OCCUR. THIS IS A BLENDED MULTI-
MODEL SOLUTION WHICH APPEARS THE BEST COURSE FOR NOW GIVEN CURRENT
OBSERVATIONAL DATA. USING THIS QPF AND ALLOWING FOR 0.01-0.03
INCHES OF SWE MELT PER HOUR INDICATES MODEST TO LOCALLY SHARP
RISES IN EXCESS OF 4-5 FEET TODAY. WHILE WIDESPREAD OPEN WATER
FLOODING IS NOT EXPECTED GIVEN AT LEAST SOME ABSORPTION OF THE
RAIN INTO THE EXISTENT "NON-RIPE" SNOWPACK...THESE RISES MAY BE
MORE THAN SUFFICIENT TO PRODUCE ICE MOVEMENT AND/OR BREAKUP ACROSS
SCATTERED WATERSHEDS. THIS SEEMS LOGICAL SEEING ICE
MOVEMENT/BREAKUP TYPICALLY OCCURS WHEN RISES ARE ON THE ORDER OF
3X THE ICE THICKNESS. WHILE WE`LL HAVE TO WAIT AND SEE HOW THIS
COMPLEX SITUATION PANS OUT...CERTAINLY SOMETHING TO KEEP A CLOSE
EYE ON TODAY INTO TONIGHT.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR
VTZ001>006-009-016-017.
FLOOD WATCH THROUGH MONDAY MORNING FOR VTZ009>012-019.
WINTER WEATHER ADVISORY UNTIL 11 AM EDT MONDAY FOR VTZ007-008-
010-012-018-019.
WINTER WEATHER ADVISORY FROM 2 PM THIS AFTERNOON TO 11 AM EDT
MONDAY FOR VTZ011.
NY...WINTER STORM WARNING UNTIL 2 PM EDT THIS AFTERNOON FOR NYZ030-
031-034.
WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR
NYZ026>029-035-087.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...LAHIFF
SHORT TERM...LAHIFF
LONG TERM...JMG
AVIATION...BANACOS/JMG
HYDROLOGY...JMG
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
340 AM EDT SUN MAR 30 2014
.SYNOPSIS...
A MOISTURE LADEN STORM SYSTEM WILL IMPACT OUR REGION TONIGHT INTO
SUNDAY. THIS SYSTEM WILL PRODUCE A MIXTURE OF RAIN...SLEET AND
SNOW...WITH SOME ICE ACCUMULATION ACROSS PORTIONS OF EASTERN
VERMONT. HEAVY RAINFALL ACROSS SOUTHERN VERMONT...COMBINED WITH
MELTING SNOW WILL PRODUCE INCREASED HYDRO CONCERNS OVER THE
WEEKEND.
&&
.NEAR TERM /UNTIL 2 PM THIS AFTERNOON/...
AS OF 840 PM EDT SATURDAY...UPDATED TO UPGRADE PARTS OF THE
NORTHERN ADIRONDACK MOUNTAINS TO WINTER STORM WARNINGS.
PRECIPITATION HAS NOW MADE IT INTO PORTIONS OF SOUTHERN
VERMONT...ADIRONDACKS...AND INTO WATERTOWN NEW YORK. SHOULD
CONTINUE TO SEE IT MOVE NORTHWARD INTO CENTRAL VERMONT BETWEEN
9-10 PM...THE BURLINGTON AREA 10-11 PM..AND ACROSS THE ENTIRE NORTH
COUNTRY BY MIDNIGHT. HEAVIEST PRECIP STILL APPEARS IT WILL FALL BETWEEN
06Z AND 12Z. VERTICAL TEMPERATURE PROFILES REMAIN VERY TRICKY WITH
NEARLY ISOTHERMAL PROFILE FROM THE SURFACE TO 825-MB CENTERED
AROUND 0C. DYNAMIC/EVAPORATIONAL COOLING SHOULD HELP TO COOL THE
COLUMN AT LEAST IN HEAVIER PRECIPITATION IN THE ADVISORY AND
WARNING AREA...ESPECIALLY NORTHERN NEW YORK. ONE CAVEAT TO
NOTE...LATEST RAP SOLUTIONS ARE CONSIDERABLY WARMER AND WOULD
FAVOR MORE RAIN OVER SNOW/SLEET FOR MUCH OF VERMONT. STILL THINK
THAT ENOUGH COOLING TO TAKE PLACE FOR A GENERAL 2-5" OF SNOW FOR
THE NORTHERN HALF OF VERMONT. IN THE ADIRONDACKS...TEMPERATURES
HAVE ALREADY FALLEN TO 32 DEGREES OR LOWER...WITH LOW LEVEL COLD
NORTHEAST FLOW LOCKED IN. WITH AT LEAST 0.75" OF LIQUID
EQUIVALENT PRECIPITATION HEADED INTO SUB-FREEZING AIR...FELT IT
WAS NECESSARY TO UPGRADE TO WARNINGS THERE. EVEN THE WARMER RAP
SOLUTIONS ARE COLD ENOUGH FOR ALL FROZEN PRECIPITATION OVER THE
ADIRONDACKS. EXPECTING PRIMARILY SNOW...ALTHOUGH THE TEMPERATURE
PROFILE IS STILL QUITE MARGINAL SO SOME SLEET/RAIN/FREEZING RAIN
MIX STILL LIKELY AT TIMES. LOOKING AT 4-8" THERE WITH THE
POSSIBILITY OF SOME LOCALLY HIGHER AMOUNTS.
COLD NORTHEAST WINDS ALSO LOCKED INTO THE SAINT LAWRENCE
VALLEY...BUT BOUNDARY LAYER WILL BE MORE MARGINAL AS ITS A DEEPER
VALLEY...AND PRECIP AMOUNTS LIGHTER...SO ADVISORY LEVEL SNOWS OF
3-5" STILL LOOK GOOD.
ELSEWHERE ACROSS SOUTHERN VERMONT...PRECIPITATION WILL FALL AS
MAINLY RAIN...WITH SOME MIXED SNOW/SLEET/FREEZING RAIN. SNOW
ACCUMULATIONS WILL GENERALLY BE LESS THAN ONE INCH...WITH SOME ICE
ACCRUAL OF UP TO A TENTH OF AN INCH IN ISOLATED LOCATIONS. BIGGEST
CONCERN THERE WILL BE 1-1.5" OF RAIN WHICH MAY LEAD TO ICE JAM
FLOODING.
&&
.SHORT TERM /2 PM THIS AFTERNOON THROUGH TUESDAY/...
AS OF 402 PM EDT SATURDAY...FOR SUNDAY NIGHT INTO MONDAY...WE WILL
HAVE TO WATCH FOR THE POSSIBILITY OF ANOTHER ROUND OF MIXED
PRECIPITATION. THIS DUE TO SHORTWAVE ROTATING AROUND THE SLOWLY
DEPARTING UPPER LOW. MODELS HAVE TRENDED FURTHER WEST WITH THE
UPPER LOW AND SHORTWAVE...SO CONFIDENCE INCREASING THAT WE WILL AT
LEAST SEE SOME LIGHT SLEET AND OR RAIN/FREEZING RAIN/DRIZZLE
SUNDAY NIGHT INTO MONDAY. GREATEST CHANCES WILL BE OVER EASTERN
ZONES DUE PROXIMITY WITH UPPER LOW. TEMPS MARGINAL FOR SNOW/RAIN
OR MIXED PRECIPITATION ONCE AGAIN. LOOK FOR LOWS SUNDAY NIGHT IN
THE MID 20S TO LOWER 30S AND HIGHS MONDAY NEAR 40. SLOW
IMPROVEMENT MONDAY NIGHT AS THE UPPER LOW EXITS TO THE EAST.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 340 AM EDT SUNDAY...SEASONABLE EARLY SPRING TEMPERATURES
ALONG WITH PERIODIC CHANCES OF RAIN OR SNOW SHOWERS WILL BE THE
RULE DURING THE MIDDLE TO LATER PORTIONS OF NEXT WEEK. BEST SHOT
AT PCPN WILL OCCUR TUE NT/WED MORNING...THEN AGAIN BY NEXT
WEEKEND. THE MID-WEEK SYSTEM WILL BE RATHER WEAK AS NORTHERN
STREAM SHORTWAVE ENERGY PASSES TO OUR NORTH. THUS PCPN SHOULD BE
LIGHT AT BEST WITH MANY AREAS REMAINING DRY...ESP ACROSS OUR
SOUTHERN COUNTIES. THE SYSTEM FOR NEXT WEEKEND A LITTLE MORE
ROBUST SO A BETTER SHOT AREA WIDE FOR RAIN/SNOW SHOWERS. IN
BETWEEN (WED AFTERNOON THROUGH FRIDAY MORNING) GENERALLY HIGH
PRESSURE WITH CLEAR/PTLY CLOUDY SKIES AND DRY WEATHER EXPECTED.
HIGHS GENERALLY IN THE 40S THROUGH THE PERIOD WITH A SPOT 50 HERE
AND THERE POSSIBLE WED-FRI. OVERNIGHT LOWS GENERALLY FROM 25 TO 35
THOUGH MAINLY 20S WED NT/THU NT WITH AFOREMENTIONED HIGH PRESSURE
IN CONTROL AND BETTER SHOT AT PARTIALLY CLEAR SKIES.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
THROUGH 06Z MONDAY...WIDESPREAD MVFR/IFR ACROSS THE REGION IN
MODERATE TO HEAVY MIXED PCPN AND/OR RAIN AS LOW PRESSURE ALONG THE
NORTHERN MID-ATLANTIC COAST DRAWS COPIOUS MOISTURE NORTHWARD.
TERMINAL SPECIFIC DETAILS BELOW...
KBTV...MIX OF RAIN/FZRA THROUGH 12Z...THEN MAINLY LT RAIN TAPERING
TO SHOWERS AFTER 18Z. VFR/MVFR FLYING CONDS EXPECTED THROUGH THE
PERIOD W/BRIEF IFR POSSIBLE. WINDS NORTH/NORTHWESTERLY 7-15 KTS.
KMPV...MIX OF RAIN/FZRA THROUGH 12Z...THEN MAINLY LT RAIN TAPERING
TO SHOWERS AFTER 18Z. IFR/MVFR CONDS EXPECTED THROUGH THE PERIOD.
WINDS LGT AND VRB THROUGH 12Z...THEN NORTH/NORTHWESTERLY 6-12 KTS
THEREAFTER.
KRUT...PERIODS OF LIGHT RAIN...TAPERING TO SHOWERS BY 18Z. MIX OF
VFR/MVFR FLYING CONDS EXPECTED THROUGH THE PERIOD. WINDS EASTERLY
8 TO 15 KTS WITH GUSTS TO 20 KTS...TRENDING NORTH TO NORTHEASTERLY
AFTER 12Z.
KPBG...LIGHT TO MODERATE SNOW THROUGH 10-12Z...THEN MIXING WITH
SLEET. IFR LIKELY THROUGH 15Z...TRENDING MVFR THEREAFTER. SOME MIX
WITH RAIN ALSO POSSIBLE AFTER 16Z BEFORE PCPN TAPERS TO SHOWERS.
WINDS NORTHERLY 10-18 KTS AND TRENDING GUSTY TO 25 KTS THIS
AFTERNOON.
KMSS...LIGHT TO MODERATE SNOW EXPECTED THROUGH MUCH OF THE
PERIOD...TAPERING TO SCT SHSN AFTER 00Z MONDAY. IFR FLYING CONDS
EXPECTED THROUGH AFTERNOON...TRENDING MVFR AFTER 18Z. WINDS
NORTHEASTERLY 15 TO 22 KTS WITH GUSTS TO 30 KTS EXPECTED...ABATING
SLIGHTLY TOWARD EVENING. CONSIDERABLE BLSN LIKELY.
KSLK...LIGHT/MODERATE SNOW EXPECTED WITH SOME MIX OF FZRA/PL
POSSIBLE...TAPERING TO SCT SHSN/SHRA AFTER 18Z. WIDESPREAD
IFR...TRENDING MVFR AFTER 18Z. WINDS NORTHEASTERLY 6-12
KTS...OCCNL GUSTY TO 20KTS THIS AFTERNOON.
OUTLOOK 06Z MONDAY THROUGH THURSDAY...
06Z MONDAY TO 18Z MONDAY...TRENDING SLOWLY TO VFR FROM WEST TO
EAST AS LIGHT RAIN/SNOW TAPERS OFF. BEST SHOT AT CONTINUED LIGHT
PCPN AND MVFR/IFR AT ERN TERMINALS OF KMPV/KRUT. AGAIN...HIGHEST
CONFIDENCE OF BETTER FLIGHT CONDS AT NRN NY TERMINALS WITH
CONTINUED UNCERTAINTY FURTHER EAST.
18Z MONDAY THROUGH 00Z WEDNESDAY...VFR WITH HIGH PRESSURE.
00Z WEDNESDAY THROUGH 00Z THURSDAY...VFR ALTHOUGH SOME BRIEF
PERIODS OF MVFR POSSIBLE IN SCATTERED RAIN/SNOW SHOWERS AS COLD
FRONT CROSSES REGION.
00Z THURSDAY ONWARD...VFR W/MVFR PSBL LATE THURSDAY AS WARM FRONT
APPROACHES FROM SW...BRINGING PRECIP SOUTH TO NORTH.
&&
.HYDROLOGY...
AS OF 340 AM EDT SUNDAY...COMPLEX HYDRO SITUATION WILL DEVELOP
ACROSS OUR SOUTHERN WATERSHEDS TODAY WHERE A SOAKING RAINFALL ON
THE ORDER OF 1-1.75 INCHES WILL OCCUR. THIS IS A BLENDED MULTI-
MODEL SOLUTION WHICH APPEARS THE BEST COURSE FOR NOW GIVEN CURRENT
OBSERVATIONAL DATA. USING THIS QPF AND ALLOWING FOR 0.01-0.03
INCHES OF SWE MELT PER HOUR INDICATES MODEST TO LOCALLY SHARP
RISES IN EXCESS OF 4-5 FEET TODAY. WHILE WIDESPREAD OPEN WATER
FLOODING IS NOT EXPECTED GIVEN AT LEAST SOME ABSORPTION OF THE
RAIN INTO THE EXISTENT "NON-RIPE" SNOWPACK...THESE RISES MAY BE
MORE THAN SUFFICIENT TO PRODUCE ICE MOVEMENT AND/OR BREAKUP ACROSS
SCATTERED WATERSHEDS. THIS SEEMS LOGICAL SEEING ICE
MOVEMENT/BREAKUP TYPICALLY OCCURS WHEN RISES ARE ON THE ORDER OF
3X THE ICE THICKNESS. WHILE WE`LL HAVE TO WAIT AND SEE HOW THIS
COMPLEX SITUATION PANS OUT...CERTAINLY SOMETHING TO KEEP A CLOSE
EYE ON TODAY INTO TONIGHT.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR
VTZ001>010-012-016>019.
FLOOD WATCH THROUGH MONDAY MORNING FOR VTZ009>012-019.
NY...WINTER STORM WARNING UNTIL 2 PM EDT THIS AFTERNOON FOR NYZ030-
031-034.
WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR
NYZ026>029-035-087.
&&
$$
SYNOPSIS...RJS
NEAR TERM...MUCCILLI
SHORT TERM...RJS
LONG TERM...JMG
AVIATION...JMG/BANACOS
HYDROLOGY...JMG
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
133 AM EDT SUN MAR 30 2014
.SYNOPSIS...
A MOISTURE LADEN STORM SYSTEM WILL IMPACT OUR REGION TONIGHT INTO
SUNDAY. THIS SYSTEM WILL PRODUCE A MIXTURE OF RAIN...SLEET AND
SNOW...WITH SOME ICE ACCUMULATION ACROSS PORTIONS OF EASTERN
VERMONT. HEAVY RAINFALL ACROSS SOUTHERN VERMONT...COMBINED WITH
MELTING SNOW WILL PRODUCE INCREASED HYDRO CONCERNS OVER THE
WEEKEND.
&&
.NEAR TERM /UNTIL 2 PM THIS AFTERNOON/...
AS OF 840 PM EDT SATURDAY...UPDATED TO UPGRADE PARTS OF THE
NORTHERN ADIRONDACK MOUNTAINS TO WINTER STORM WARNINGS.
PRECIPITATION HAS NOW MADE IT INTO PORTIONS OF SOUTHERN
VERMONT...ADIRONDACKS...AND INTO WATERTOWN NEW YORK. SHOULD
CONTINUE TO SEE IT MOVE NORTHWARD INTO CENTRAL VERMONT BETWEEN
9-10 PM...THE BURLINGTON AREA 10-11 PM..AND ACROSS THE ENTIRE NORTH
COUNTRY BY MIDNIGHT. HEAVIEST PRECIP STILL APPEARS IT WILL FALL BETWEEN
06Z AND 12Z. VERTICAL TEMPERATURE PROFILES REMAIN VERY TRICKY WITH
NEARLY ISOTHERMAL PROFILE FROM THE SURFACE TO 825-MB CENTERED
AROUND 0C. DYNAMIC/EVAPORATIONAL COOLING SHOULD HELP TO COOL THE
COLUMN AT LEAST IN HEAVIER PRECIPITATION IN THE ADVISORY AND
WARNING AREA...ESPECIALLY NORTHERN NEW YORK. ONE CAVEAT TO
NOTE...LATEST RAP SOLUTIONS ARE CONSIDERABLY WARMER AND WOULD
FAVOR MORE RAIN OVER SNOW/SLEET FOR MUCH OF VERMONT. STILL THINK
THAT ENOUGH COOLING TO TAKE PLACE FOR A GENERAL 2-5" OF SNOW FOR
THE NORTHERN HALF OF VERMONT. IN THE ADIRONDACKS...TEMPERATURES
HAVE ALREADY FALLEN TO 32 DEGREES OR LOWER...WITH LOW LEVEL COLD
NORTHEAST FLOW LOCKED IN. WITH AT LEAST 0.75" OF LIQUID
EQUIVALENT PRECIPITATION HEADED INTO SUB-FREEZING AIR...FELT IT
WAS NECESSARY TO UPGRADE TO WARNINGS THERE. EVEN THE WARMER RAP
SOLUTIONS ARE COLD ENOUGH FOR ALL FROZEN PRECIPITATION OVER THE
ADIRONDACKS. EXPECTING PRIMARILY SNOW...ALTHOUGH THE TEMPERATURE
PROFILE IS STILL QUITE MARGINAL SO SOME SLEET/RAIN/FREEZING RAIN
MIX STILL LIKELY AT TIMES. LOOKING AT 4-8" THERE WITH THE
POSSIBILITY OF SOME LOCALLY HIGHER AMOUNTS.
COLD NORTHEAST WINDS ALSO LOCKED INTO THE SAINT LAWRENCE
VALLEY...BUT BOUNDARY LAYER WILL BE MORE MARGINAL AS ITS A DEEPER
VALLEY...AND PRECIP AMOUNTS LIGHTER...SO ADVISORY LEVEL SNOWS OF
3-5" STILL LOOK GOOD.
ELSEWHERE ACROSS SOUTHERN VERMONT...PRECIPITATION WILL FALL AS
MAINLY RAIN...WITH SOME MIXED SNOW/SLEET/FREEZING RAIN. SNOW
ACCUMULATIONS WILL GENERALLY BE LESS THAN ONE INCH...WITH SOME ICE
ACCRUAL OF UP TO A TENTH OF AN INCH IN ISOLATED LOCATIONS. BIGGEST
CONCERN THERE WILL BE 1-1.5" OF RAIN WHICH MAY LEAD TO ICE JAM
FLOODING.
&&
.SHORT TERM /2 PM THIS AFTERNOON THROUGH MONDAY NIGHT/...
AS OF 402 PM EDT SATURDAY...FOR SUNDAY NIGHT INTO MONDAY...WE WILL
HAVE TO WATCH FOR THE POSSIBILITY OF ANOTHER ROUND OF MIXED
PRECIPITATION. THIS DUE TO SHORTWAVE ROTATING AROUND THE SLOWLY
DEPARTING UPPER LOW. MODELS HAVE TRENDED FURTHER WEST WITH THE
UPPER LOW AND SHORTWAVE...SO CONFIDENCE INCREASING THAT WE WILL AT
LEAST SEE SOME LIGHT SLEET AND OR RAIN/FREEZING RAIN/DRIZZLE
SUNDAY NIGHT INTO MONDAY. GREATEST CHANCES WILL BE OVER EASTERN
ZONES DUE PROXIMITY WITH UPPER LOW. TEMPS MARGINAL FOR SNOW/RAIN
OR MIXED PRECIPITATION ONCE AGAIN. LOOK FOR LOWS SUNDAY NIGHT IN
THE MID 20S TO LOWER 30S AND HIGHS MONDAY NEAR 40. SLOW
IMPROVEMENT MONDAY NIGHT AS THE UPPER LOW EXITS TO THE EAST.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 325 PM EDT SATURDAY...DRY START TO THE PERIOD TUESDAY
BEFORE UPPER LVL TROUGH...ASSOCIATED WITH CLOSED SFC
LOW...TRAVELS FROM THE NRN GREAT LAKES NEWD NEAR JAMES BAY BY MID
WEDNESDAY. THIS LOW WILL HAVE A WEAK FRONTAL BOUNDARY DRAPED
SOUTH...WHICH WILL BRING LOW CHC OF SHOWERS TO THE NORTH COUNTRY
TUESDAY NGT INTO WEDNESDAY...AS THIS BOUNDARY WILL HAVE LIMITED
MOISTURE AND MAIN UPPER LVL ENERGY WILL BE FAR NORTH OF THE FA.
FOR ANY PRECIP THAT DOES OCCUR...TUESDAY NGT WILL SEE SOME
SNOW...BUT WARMING TEMPS ON WEDNESDAY WILL TRANSITION SN INTO RA
BEFORE TAPERING OFF.
ANOTHER SYSTEM APPROACHING FROM CENTRAL USA WILL BRING WARM FRONT
TO THE NE LATE THURSDAY INTO FRIDAY. GFS AND ECMWF DIFFER WITH
ECMWF PERSISTING WITH RIDGE. THIS WOULD KEEP THREAT OF PRECIP TO
OUR SOUTH THRU LATE FRIDAY. MUCH UNCERTAINTY FOR THE LATTER HALF
OF THE WEEK GOING INTO THE WKND.
TEMPS THROUGHOUT THE PERIOD WILL BE NEAR NORMAL WITH MAX TEMPS IN
THE 40S IN THE VALLEYS AND 30S IN THE MTNS. MIN TEMPS WILL BE IN
THE U20S-L30S IN THE VALLEYS AND UPPER TEENS TO L20S IN THE MTNS.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
THROUGH 06Z MONDAY...WIDESPREAD MVFR/IFR ACROSS THE REGION IN
MODERATE TO HEAVY MIXED PCPN AND/OR RAIN AS LOW PRESSURE ALONG THE
NORTHERN MID-ATLANTIC COAST DRAWS COPIOUS MOISTURE NORTHWARD.
TERMINAL SPECIFIC DETAILS BELOW...
KBTV...MIX OF RAIN/FZRA THROUGH 12Z...THEN MAINLY LT RAIN TAPERING
TO SHOWERS AFTER 18Z. VFR/MVFR FLYING CONDS EXPECTED THROUGH THE
PERIOD W/BRIEF IFR POSSIBLE. WINDS NORTH/NORTHWESTERLY 7-15 KTS.
KMPV...MIX OF RAIN/FZRA THROUGH 12Z...THEN MAINLY LT RAIN TAPERING
TO SHOWERS AFTER 18Z. IFR/MVFR CONDS EXPECTED THROUGH THE PERIOD.
WINDS LGT AND VRB THROUGH 12Z...THEN NORTH/NORTHWESTERLY 6-12 KTS
THEREAFTER.
KRUT...PERIODS OF LIGHT RAIN...TAPERING TO SHOWERS BY 18Z. MIX OF
VFR/MVFR FLYING CONDS EXPECTED THROUGH THE PERIOD. WINDS EASTERLY
8 TO 15 KTS WITH GUSTS TO 20 KTS...TRENDING NORTH TO NORTHEASTERLY
AFTER 12Z.
KPBG...LIGHT TO MODERATE SNOW THROUGH 10-12Z...THEN MIXING WITH
SLEET. IFR LIKELY THROUGH 15Z...TRENDING MVFR THEREAFTER. SOME MIX
WITH RAIN ALSO POSSIBLE AFTER 16Z BEFORE PCPN TAPERS TO SHOWERS.
WINDS NORTHERLY 10-18 KTS AND TRENDING GUSTY TO 25 KTS THIS
AFTERNOON.
KMSS...LIGHT TO MODERATE SNOW EXPECTED THROUGH MUCH OF THE
PERIOD...TAPERING TO SCT SHSN AFTER 00Z MONDAY. IFR FLYING CONDS
EXPECTED THROUGH AFTERNOON...TRENDING MVFR AFTER 18Z. WINDS
NORTHEASTERLY 15 TO 22 KTS WITH GUSTS TO 30 KTS EXPECTED...ABATING
SLIGHTLY TOWARD EVENING. CONSIDERABLE BLSN LIKELY.
KSLK...LIGHT/MODERATE SNOW EXPECTED WITH SOME MIX OF FZRA/PL
POSSIBLE...TAPERING TO SCT SHSN/SHRA AFTER 18Z. WIDESPREAD
IFR...TRENDING MVFR AFTER 18Z. WINDS NORTHEASTERLY 6-12
KTS...OCCNL GUSTY TO 20KTS THIS AFTERNOON.
OUTLOOK 06Z MONDAY THROUGH THURSDAY...
06Z MONDAY TO 18Z MONDAY...TRENDING SLOWLY TO VFR FROM WEST TO
EAST AS LIGHT RAIN/SNOW TAPERS OFF. BEST SHOT AT CONTINUED LIGHT
PCPN AND MVFR/IFR AT ERN TERMINALS OF KMPV/KRUT. AGAIN...HIGHEST
CONFIDENCE OF BETTER FLIGHT CONDS AT NRN NY TERMINALS WITH
CONTINUED UNCERTAINTY FURTHER EAST.
18Z MONDAY THROUGH 00Z WEDNESDAY...VFR WITH HIGH PRESSURE.
00Z WEDNESDAY THROUGH 00Z THURSDAY...VFR ALTHOUGH SOME BRIEF
PERIODS OF MVFR POSSIBLE IN SCATTERED RAIN/SNOW SHOWERS AS COLD
FRONT CROSSES REGION.
00Z THURSDAY ONWARD...VFR W/MVFR PSBL LATE THURSDAY AS WARM FRONT
APPROACHES FROM SW...BRINGING PRECIP SOUTH TO NORTH.
&&
.HYDROLOGY...
AS OF 325 PM EDT SATURDAY...PRECIPITATION WILL BEGIN TO EDGE INTO
SOUTHERN VERMONT LATE THIS AFTN...PROGRESSING NORTHWARD
THROUGHOUT THE EVENING. THIS PRECIPITATION IS EXPECTED TO
CONTINUE THROUGH SUNDAY NIGHT...RESULTING IN OUR SOUTHERN
WATERSHEDS RECEIVING THE MOST RAINFALL ON THE ORDER OF 1-2
INCHES. AREAS FURTHER NORTH AND WEST WILL SEE MORE OF A MIXED
PRECIPITATION EVENT...WITH LESSER RAINFALL AMOUNTS.
WITH SOUTHERN WATERSHEDS RECEIVING MOSTLY RAIN...EXPECT SNOWPACK
TO ABSORB SOME OF THIS RAINFALL AS TEMPERATURES WILL GENERALLY BE
IN THE MID TO UPPER 30S THROUGHOUT THE EVENT...LEADING TO LIMITED
MELTING OF SNOWPACK. ONLY A FEW HUNDREDTHS OF AN INCH OF SNOW
WATER MELT PER HOUR EXPECTED ON TOP OF RAINFALL WILL RESULT IN
MODEST TO LOCALLY SHARP RISES IN EXCESS OF 4-5 FEET SUNDAY
MORNING/AFTERNOON. ENSEMBLE FORECASTS INDICATE NO RIVER FLOODING
EXPECTED....BUT WATER LEVEL RISES MAY BE MORE THAN SUFFICIENT TO
PRODUCE ICE MOVEMENT AND/OR BREAKUP ACROSS SCATTERED WATERSHEDS.
WILL KEEP FLOOD WATCH IN EFFECT FOR CENTRAL AND SOUTHERN VERMONT.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR
VTZ001>010-012-016>019.
FLOOD WATCH THROUGH MONDAY MORNING FOR VTZ009>012-019.
NY...WINTER STORM WARNING UNTIL 2 PM EDT THIS AFTERNOON FOR NYZ030-
031-034.
WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR
NYZ026>029-035-087.
&&
$$
SYNOPSIS...RJS
NEAR TERM...MUCCILLI
SHORT TERM...RJS
LONG TERM...KGM
AVIATION...JMG/BANACOS
HYDROLOGY...KGM
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
410 AM EDT SUN MAR 30 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE OFFSHORE LATE TONIGHT. A SURFACE TROUGH WILL
LINGER JUST WEST OF THE AREA INTO MONDAY. WEAK HIGH PRESSURE BUILDS
OVER THE REGION MONDAY NIGHT AND TUESDAY. THE HIGH WILL MOVE SOUTH
OF THE AREA TUESDAY NIGHT AND WEDNESDAY. ANOTHER COLD WILL APPROACH
THE AREA BY LATE WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1230 AM SUNDAY...UPDATED TO REDUCE POPS TO 30% FOR COASTAL
PLAINS OVERNIGHT AND 20% REST OF AREA. DRY SLOT WILL KEEP MOST OF
AREA DRY REST OF NIGHT BUT SCT SHOWERS WILL AFFECT COASTAL PLAINS
WITH CONVERGENCE JUST AHEAD OF FRONT. TORNADO WATCH WAS CANCELLED AT
10 PM. MINOR ADJUSTMENTS TO TEMPS AND SKY COVER.
/PREVIOUS DISCUSSION/
AS OF 920 PM SATURDAY...A TORNADO WATCH REMAINS IN EFFECT FOR THE
WESTERN PORTIONS OF EASTERN NC (MAINLY WEST OF HIGHWAY 17) UNTIL
1 AM. HAVE BEEN WATCHING A PERSISTENT SUPERCELL THUNDERSTORM WITH
A DEEP AND PERSISTENT MESCALINE MOVING THROUGH CENTRAL NC SINCE
730 PM. THIS STORM WILL REMAIN NW OF OUR AREA. TO THE SOUTH OF
THIS SYSTEM ADDITIONAL SHOWERS AND POSSIBLE THUNDERSTORMS WERE
DEVELOPING. THE HRRR MODEL BRINGS THIS CONVECTION INTO OUR PORTION
OF THE COASTAL PLAIN AROUND 11 PM SO WILL CONTINUE TO MONITOR. SO
FAR STORMS HAVE NOT WEAKENED WITH LOSS OF HEATING A SIGNAL THAT
THEY ARE BEING DYNAMICALLY FORCED. WILL CONTINUE TO KEEP POPS IN
THE CHANCE RANGE AS THE COVERAGE IN THE HIGH RESOLUTION MODELS
REMAINS SCATTERED. LATE TONIGHT DRY SLOTTING SHOULD END ANY
CHANCE OF PRECIPITATION UNTIL LATER SUNDAY WHEN THE UPPER LEVEL
LOW MOVES THROUGH. USED A BLEND OF THE ECMWF/MET MOS FOR LOWS WITH
READINGS IN THE UPPER 40S/LOWER 50S EXPECTED.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TODAY/...
AS OF 315 PM SATURDAY...WILL HAVE A BIT OF A LULL IN PRECIPITATION
DURING THE MORNING HOURS ON SUNDAY...BUT AS UPPER LOW CROSSES TO
OUR NORTH NEAR THE NORTH CAROLINA/VIRGINIA BORDER...THE STEEP
LAPSE RATES AND MODEST MOISTURE WILL LEAD TO A HIGH CHANCE OF
SHOWERS SUNDAY AFTERNOON. WITH GOOD COLD AIR ADVECTION...TEMPERATURES
WILL ONLY RECOVER ABOUT 5 TO 7 DEGREES AND WILL FOLLOW THE COOLER
NAM MOS GUIDANCE SUNDAY SHOWING HIGH TEMPERATURES IN THE LOW/MID
50S WITH GUSTY W/WNW WINDS.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
AS OF 4 AM SUN...UPR LOW WILL PIVOT EAST OF THE NC WATERS BY
MONDAY...LEAVING IN ITS WAKE STRONG SUBSIDENCE AS HIGH PRES SFC AND
ALOFT BUILDS IN. ATMS COLUMN WILL BE EXTREMELY DRY PER SOUNDINGS
~0.25 INCH PWATS. THIS IS BELOW THE 25TH PERCENTILE FOR LATE MARCH.
SKIES WILL BE SUNNY...WITH GUSTY NW WINDS AS GRADIENT REMAINS
BETWEEN DEPARTING LOW AND BUILDING HIGH. A FAIRLY HIGH TEMP GRADIENT
ACROSS THE FA...WITH LOW LEVEL THICKNESSES SUPPORTIVE OF HIGHS IN
THE LOW 70S WEST...TO 50S ALONG THE OBX. STEEP LOW LEVEL LAPSE RATES
WILL PROMOTE EFFICIENT MIXING WITH DRY AIR ALOFT MIXING TO THE SFC.
WILL HAVE TO WATCH FOR FIRE WEATHER CONCERNS AS MIN RH VALS PLUMMET
TO THE 20-30 PERCENTILE RANGE BY MON AFTERNOON WITH A GUSTY NW WIND.
HIGH WILL BUILD IN MON NIGHT WITH WINDS QUICKLY DIMINISHING BY
NIGHTFALL WITH LOSS OF TURBULENT MIXING. WITH CLR SKIES...CALM
WINDS...AND DRY ATMS...WILL SEE LOWS DROP BACK TO THE UPR 30S/LOW
40S MOST AREAS AWAY FROM THE BEACHES. LARGE DIURNAL SWING ON TUE AS
THICKNESSES BUILD FURTHER AND DRY ATMOSPHERE REMAINS DUE TO ZONAL
FLOW ALOFT. HIGHS WILL REACH WELL INTO THE 70S INLAND TO 60S COAST.
LARGE DIURNAL SEESAW CONTINUES TUE NIGHT AS DECOUPLING OCCURS ONCE
AGAIN...AND WITH CONTINUED DRY ATMS TEMPS FALL BACK TO THE 40S.
THICKNESSES BUILD FURTHER ON WED AND ECM ENSMOS IN GOOD AGREEMENT
WITH LOCAL LOW LEVEL THICKNESS STUDY IN HIGHS IN THE UPPER 70S...60S
BEACHES. LOWS DROP BACK TO ~50 WED NIGHT AS SPRAWLING DRY HIGH PRES
REMAINS LOCKED IN ACROSS SE CONUS.
THUR AND FRI LOOK TO BE THE WARMEST DAYS OF THE WEEK WITH HIGHS
REACHING OR PERHAPS EXCEEDING 80 AS 1000-850MB THICKNESSES APPROACH
1390M. DEWPOINTS WILL BE ON THE RISE DURING THIS TIME PERIOD SO
OVERNIGHT LOWS WILL BE WARMER GENERALLY IN THE MID/UPR 50S.
MODEL DIFFERENCES TOWARDS THE WEEKEND COME INTO PLAY...AS IS
EXPECTED THIS FAR OUT. THE ECM KEEPS THE SE CONUS RIDGE IN PLACE
WHILE PUSHING A WEAK COLD FRONT INTO THE REGION...AND KEEPING BEST
DYNAMICS WELL TO THE NORTH AS STORM TRACK REMAINS WELL NORTH OF THE
AREA. MEANWHILE...THE DETERMINISTIC 30/00Z GFS INDICATES A STRONGER
COLD FRONT PUSHING THROUGH FRI NIGHT/EARLY SAT WITH MORE AMPLIFIED
LONG WAVE TROFINESS ACROSS THE E CONUS. THIS SCENARIO HOWEVER
LACKS SUPPORT FROM THE NCEP ENSEMBLE MEAN...WHICH INDICATES A LESS
AMPLIFIED TROUGH ACROSS THE E CONUS. THEREFORE...HAVE ONLY INDICATED
SMALL POPS LATE FRI INTO SAT.
&&
.AVIATION /08Z SUNDAY THROUGH FRIDAY/...
SHORT TERM /THROUGH 06Z MONDAY/...
AS OF 130 AM SUNDAY...CONDITIONS HAVE IMPROVED TO VFR ALL BUT KPGV
WHERE MVFR SCU STILL LINGERING. SCU VFR CIGS EXPECTED TO REDEVLOP
ALL SITES 09Z-12Z AS UPR LOW MOVES INTO AREA FROM W. LOWER MVFR CIGS
WILL DEVELOP WITH HEATING BY 15Z WITH SCT SHRA PSBL THROUGH AFTN AS
COLD CORE UPR LOW MOVES ACROSS NRN SECTIONS. CLEARING EXPECTED
DURING EVENING WITH LOSS OF HEATING. W WINDS WILL GUST UP TO 20-25
KT TODAY...DIMINISING AND BECOME NW THIS EVENING.
LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 4 AM SUN...EXCELLENT FLYING CONDITIONS FOR THE LONG TERM AS
HIGH PRES WILL BE IN CONTROL. GUSTY NW WINDS WILL CONTINUE ON MONDAY
BUT THE REST OF THE WEEK WINDS WILL BE LIGHT. NOT MUCH CHANCE FOR
EVENT RADIATION FOG DURING THE OVERNIGHT HOURS THIS COMING WEEK AS
ATMOSPHERE WILL BE VERY DRY. BETTER CHANCE FOR FOG AT NIGHT LATER IN
THE WEEK (THUR/FRI) AS DEWPOINT RISE.
&&
.MARINE...
SHORT TERM /TONIGHT AND SUNDAY/...
AS OF 1230 AM SUNDAY...NO CHANGES WITH UPDATE.
/PREVIOUS DISCUSSION/
AS OF 920 PM SATURDAY...NO CHANGES TO PREVIOUS FORECAST THINKING
OTHER THAN TO EXTEND THE ADVISORIES FOR THE SOUNDS THROUGH EARLY
MONDAY. GUSTY SE/S WINDS WILL CONTINUE TONIGHT AND HAVE ADDED THE
ALBEMARLE SOUND TO THE SMALL CRAFT ADVISORY THAT WILL REMAIN IN
EFFECT UNTIL 5 AM SUNDAY. WILL INITIALIZE WINDS AT 20 TO 25 KNOTS
FOR ALL WATERS...EXCEPT 25 TO 30 KNOTS OVER THE OREGON INLET TO
OCRACOKE LEG WHERE WINDS CONTINUE TO BE STRONGEST. THESE WINDS
SHOULD SETTLE DOWN AFTER MIDNIGHT AS WINDS VEER TO MORE SW LATE.
PER LATEST NWPS WAVE MODEL...SEAS OF 9 TO 13 FEET WILL PREVAIL
OVER THE NORTHERN AND CENTRAL WATERS WITH GENERALLY 7 TO 10 FEET
OVER SOUTHERN PORTIONS...WITH A SLIGHT DROP IN THE MORE WESTERLY
FLOW EXPECTED DURING THE DAY ON SUNDAY.
LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 4 AM SUN...MONDAY WILL CONTINUE TO BE WINDY WITH SCA NW
WINDS...THOUGH THESE WINDS WILL WIND DOWN THROUGH THE DAY AS LOW
PRES MOVES AWAY FROM THE EASTERN ATLANTIC WATERS. SEAS WILL STILL
REMAIN ELEVATED HOWEVER EVEN WHEN WINDS DROP BELOW 25 KT...AS
LINGERING LONG PERIOD SWELL DOMINATES THE NRN/CENTRAL WATERS INTO
MON NIGHT. SEAS HERE WILL DROP BELOW 6 FT FINALLY...WITH HIGH PRES
BUILDING IN FOR TUE THROUGH MUCH OF NEXT WEEK. THE HIGH WILL BE
ANCHORED TO THE SOUTH OF THE AREA...AND THEREFORE WINDS WILL BE
SOUTHWEST FOR MUCH OF THE PERIOD...OCNL REACHING 20 KT MID TO LATE
WEEK. THIS MAY BRING MARGINAL SCA TO ESPECIALLY THE SOUTHERN/CENTRAL
WATERS AS SEAS MAY REACH 6 FT HERE.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...GALE WARNING FROM 2 PM THIS AFTERNOON TO 11 AM EDT MONDAY FOR
AMZ135-152-154.
SMALL CRAFT ADVISORY UNTIL 5 PM EDT MONDAY FOR AMZ130.
GALE WARNING FROM 2 PM THIS AFTERNOON TO 8 AM EDT MONDAY FOR
AMZ156-158.
GALE WARNING FROM 6 PM THIS EVENING TO 11 AM EDT MONDAY FOR
AMZ150.
&&
$$
SYNOPSIS...CTC
NEAR TERM...CTC/JME
SHORT TERM...CTC
LONG TERM...TL
AVIATION...JME/TL/LEP
MARINE...CTC/JME/TL
AREA FORECAST DISCUSSION
NWS RALEIGH NC
315 AM EDT SUN MAR 30 2014
.SYNOPSIS... A COLD FRONT WILL SWEEP EAST THROUGH CENTRAL NORTH
CAROLINA EARLY THIS MORNING... AND WILL BE FOLLOWED BY BRISK AND
GUSTY WINDS FROM THE NORTHWEST PULLING COOLER AIR INTO THE REGION.
HIGH PRESSURE WILL BUILD IN FROM THE WEST TONIGHT INTO EARLY NEXT
WEEK.
&&
.NEAR TERM /TODAY THROUGH TONIGHT/...
AS OF 300 AM SUNDAY...
THE PRIMARY WEATHER CONCERN TODAY IS THE STRONG GUSTY NW WINDS AND
POTENTIALLY ADVERSE IMPACTS SUCH AS DOWNED BRANCHES AND WEAKLY
ROOTED TREES. CURRENTLY... SHORT BANDS OF SHOWERS PRODUCING LOCALLY
ENHANCED WINDS CONTINUE TO PIVOT AROUND THE MID LEVEL LOW OVER SW VA
THIS MORNING... MAINLY AFFECTING THE NRN CWA AS POCKETS OF VORTICITY
STREAK TO THE NNE ON THE SRN/ERN SIDE OF THE LOW. THIS LOW IS
EXPECTED TO TRACK EASTWARD ALONG THE NC/VA STATE LINE THROUGH
MIDDAY... SHIFTING NE OFF THE TIDEWATER/DELMARVA SHORE DURING THE
MID TO LATE AFTERNOON... AND IT`S EXPECTED TO BRING PATCHY SHOWERS
(MOVING MORE WEST-TO-EAST) THROUGH MID AFTERNOON ACROSS OUR NRN
CWA... WHERE FORECAST SOUNDINGS AND EXTRAPOLATION OF UPSTREAM
CONDITIONS SUPPORT A RATHER DEEP LAYER OF MOISTURE AT 850-700 MB.
THE COMPARATIVELY DRY AND WELL-MIXED SUBCLOUD LAYER HOWEVER WILL
GREATLY LIMIT QPF. REGARDING TODAY`S WIND... THE MSLP GRADIENT
BETWEEN THE DEEP SURFACE LOW ANALYZED OVER THE CHESAPEAKE BAY/SRN
DELMARVA AND THE INCOMING SURFACE HIGH FROM THE WEST TIGHTENS UP
THIS MORNING... AND STATISTICAL GUIDANCE AS WELL AS HIGH-RES MODEL
OUTPUT SUCH AS THE HRRR AND LOCAL WRF ALL SUPPORT SUSTAINED WINDS OF
15-25 MPH MAINLY OVER THE WRN AND SRN HALVES OF THE CENTRAL NC
FORECAST AREA... AND TRANSPORT OF MOMENTUM WITHIN THE GROWING MIXED
LAYER INDICATES GUSTS OF 30-36 KTS OVER THIS SAME AREA. WHILE THESE
SPEEDS MAY NOT QUITE REACH OUR WIND ADVISORY CRITERIA EVERYWHERE...
THE ANTICIPATED IMPACTS (A FEW DOWNED BRANCHES/TREES AND SPORADIC
POWER OUTAGES) WARRANT ISSUANCE OF A WIND ADVISORY... TO BE IN
EFFECT FOR AREAS WEST AND SOUTH OF THE TRIANGLE THROUGH MID EVENING
(WHEN WINDS ARE EXPECTED TO SUBSIDE). BELOW-NORMAL LOW LEVEL
THICKNESSES COMBINED WITH CONSIDERABLE CLOUDINESS PARTICULARLY OVER
THE NRN TWO-THIRDS OF THE CWA WILL HOLD TEMPS DOWN TODAY... AND
EXPECT HIGHS OF 53-62... AROUND 10-12 DEGREES BELOW NORMAL. THE
DEPARTURE OF THE SURFACE AND MID LEVEL LOWS TO OUR NE AFTER
NIGHTFALL AND STRONG SUBSIDENCE (100-120 M MID LEVEL HEIGHT RISES)
SHOULD FOSTER QUICK CLEARING FROM WSW TO ENE. WINDS WILL DECREASE
BUT SHOULD STILL HOLD UP ENOUGH TO KEEP THE LOW LEVELS STIRRED
OVERNIGHT... KEEPING TEMPS FROM FALLING DOWN TO THE FORECAST DEW
POINTS (WHICH SHOULD FALL TO THE MID 20S TO AROUND 30). AS SUCH...
EXPECT LOWS TO STAY ABOVE FREEZING TONIGHT. DESPITE LOWS IN THE MID
30S IN MANY AREAS... THE DRY AIR SHOULD LIMIT FROST DEVELOPMENT
TONIGHT... BUT WILL TAKE ANOTHER LOOK AT THIS LATER TODAY. LOWS
MAINLY 35-40. -GIH
&&
.SHORT TERM /MONDAY AND MONDAY NIGHT/...
AS OF 315 AM SUNDAY...
PLENTY OF SUNSHINE EXPECTED MONDAY... WITH CONTINUED DRY AIR
ADVECTION THROUGH THE COLUMN AND HIGH PRESSURE STARTING TO BUILD IN
AT THE SURFACE... AND MID LEVEL RIDGING APPROACHING FROM THE WEST. A
BREEZE OUT OF THE NW SHOULD PERSIST BUT NOT NEARLY AS STRONG AS WE
SHOULD SEE TODAY. LOW LEVEL THICKNESSES RECOVER NICELY TO NEAR-
NORMAL LEVELS MON MORNING AND RISE QUICKLY THROUGH THE DAY...
SUPPORTING HIGHS FROM THE UPPER 60S NE TO MID 70S SW... A BIT ABOVE
NORMAL FOR THIS TIME OF YEAR. EXPECT GOOD RADIATIONAL COOLING MON
NIGHT... ALTHOUGH THE INCREASING SURFACE DEW POINTS MON NIGHT WILL
OFFSET THE CALM TO VERY LIGHT WINDS TO KEEP TEMPS FROM FALLING TOO
MUCH. LOWS 38-42... JUST SLIGHTLY BELOW NORMAL. -GIH
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 255 AM SUNDAY...
A SUBTROPICAL RIDGE WILL DEVELOP OVER THE SOUTHEAST US BY TUESDAY
WITH A SURFACE HIGH OFF THE SOUTHEAST COAST. THIS WARM
PATTERN...WITH LOW LEVEL THICKNESSES CLIMBING ABOVE 1370M...WILL
SUPPORT HIGHS IN THE MID AND UPPER 70S EACH DAY...WITH LOWER 80S NOT
OUT OF THE QUESTION ACROSS THE SOUTH AND EAST WEDNESDAY AND
THURSDAY.
A SHORTWAVE LIFTING THROUGH THE GREAT LAKES REGION WILL SEND A
MOSTLY DRY COLD FRONT INTO THE MID-ATLANTIC STATES TUESDAY
AFTERNOON...BUT GIVEN THE STRENGTH OF THE RIDGE...EXPECT THIS FRONT
OR REMNANT TROUGH TO REMAIN NORTH OF THE AREA. A MORE VIGOROUS
SYSTEM IS FORECAST TO LIFT THROUGH THE MIDWEST STATES ON
FRIDAY...THOUGH THE GFS AND ECMWF DIFFER REGARDING THE STRENGTH OF
THE WAVE AND THE TIMING OF THE ASSOCIATED COLD FRONT. PREFER A
SOLUTION SLOWER THAN THE ECMWF ON FRIDAY...BUT NOT AS SLOW AS THE
GFS WHICH DOESNT BRING THE FRONT IN UNTIL SATURDAY. NEITHER
SOLUTION LOOKS TO DRAW A TON OF MOISTURE FROM THE GULF...SO WILL
KEEP POPS CAPPED AT SLIGHT CHANCE NOW BASED ON THE PATTERN AND MODEL
DIFFERENCES.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 155 AM SUNDAY...
THE BIGGEST AVIATION STORY FOR THE NEXT SEVERAL HOURS IS THE COLD
FRONTAL PASSAGE AND RESULTANT SHIFT IN SURFACE WINDS TO WESTERLY
THEN NORTHWEST... WITH AN INCREASE TO 15-20 KTS GUSTING TO 25-35
KTS... STRONGEST AFTER 17Z THIS AFTERNOON AS OUR LOW LEVELS MIX MORE
DEEPLY. THIS MAY POSE A CROSSWIND THREAT FOR AIRCRAFT AT
GSO/RDU/FAY/RWI. CURRENT CIGS ARE MOSTLY VFR... BUT PATCHY SHOWERS
ACROSS THE AREA MAY BRIEFLY REDUCE CIGS TO MVFR THROUGH 09Z.
OTHERWISE... WITH EARLY-DAY HEATING AND RESIDUAL MOISTURE ALOFT...
EXPECT TO SEE A PERIOD OF MVFR CIGS MAINLY AT RDU/RWI BETWEEN 12Z
AND 17Z THIS MORNING/MIDDAY. THESE CIGS SHOULD LIFT TO VFR SOON
AFTER 17Z. ELSEWHERE... ANY CIGS ARE LIKELY TO BE VFR... AND VSBYS
WILL BE VFR AREAWIDE THROUGH TONIGHT. WINDS WILL DECREASE THIS
EVENING (AFTER 01Z) TO 10-15 KTS WITH ONLY SPORADIC GUSTS TO 20 KTS
FROM THE NW THROUGH THE END OF THE TAF VALID PERIOD.
LOOKING BEYOND 06Z TONIGHT: HIGH CONFIDENCE IN VFR CONDITIONS AT ALL
SITES THROUGH THURSDAY... AS HIGH PRESSURE BUILDS OVER THE REGION
AND REMAINS OVER AND JUST OFF THE SOUTHEAST COAST. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 10 PM EDT THIS EVENING FOR NCZ007-021>024-
038>040-073>077-083>086-088.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...HARTFIELD
LONG TERM...SMITH
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
214 AM EDT SUN MAR 30 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE OFFSHORE LATE TONIGHT. A SURFACE TROUGH WILL
LINGER JUST WEST OF THE AREA INTO MONDAY. WEAK HIGH PRESSURE BUILDS
OVER THE REGION MONDAY NIGHT AND TUESDAY. THE HIGH WILL MOVE SOUTH
OF THE AREA TUESDAY NIGHT AND WEDNESDAY. ANOTHER COLD WILL APPROACH
THE AREA BY LATE WEEK.
&&
.NEAR TERM /THROUGH SUNDAY/...
AS OF 1230 AM SUNDAY...UPDATED TO REDUCE POPS TO 30% FOR COASTAL
PLAINS OVERNIGHT AND 20% REST OF AREA. DRY SLOT WILL KEEP MOST OF
AREA DRY REST OF NIGHT BUT SCT SHOWERS WILL AFFECT COASTAL PLAINS
WITH CONVERGENCE JUST AHEAD OF FRONT. TORNADO WATCH WAS CANCELLED AT
10 PM. MINOR ADJUSTMENTS TO TEMPS AND SKY COVER.
/PREVIOUS DISCUSSION/
AS OF 920 PM SATURDAY...A TORNADO WATCH REMAINS IN EFFECT FOR THE
WESTERN PORTIONS OF EASTERN NC (MAINLY WEST OF HIGHWAY 17) UNTIL
1 AM. HAVE BEEN WATCHING A PERSISTENT SUPERCELL THUNDERSTORM WITH
A DEEP AND PERSISTENT MESCALINE MOVING THROUGH CENTRAL NC SINCE
730 PM. THIS STORM WILL REMAIN NW OF OUR AREA. TO THE SOUTH OF
THIS SYSTEM ADDITIONAL SHOWERS AND POSSIBLE THUNDERSTORMS WERE
DEVELOPING. THE HRRR MODEL BRINGS THIS CONVECTION INTO OUR PORTION
OF THE COASTAL PLAIN AROUND 11 PM SO WILL CONTINUE TO MONITOR. SO
FAR STORMS HAVE NOT WEAKENED WITH LOSS OF HEATING A SIGNAL THAT
THEY ARE BEING DYNAMICALLY FORCED. WILL CONTINUE TO KEEP POPS IN
THE CHANCE RANGE AS THE COVERAGE IN THE HIGH RESOLUTION MODELS
REMAINS SCATTERED. LATE TONIGHT DRY SLOTTING SHOULD END ANY
CHANCE OF PRECIPITATION UNTIL LATER SUNDAY WHEN THE UPPER LEVEL
LOW MOVES THROUGH. USED A BLEND OF THE ECMWF/MET MOS FOR LOWS WITH
READINGS IN THE UPPER 40S/LOWER 50S EXPECTED.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH 6 PM SUNDAY/...
AS OF 315 PM SATURDAY...WILL HAVE A BIT OF A LULL IN PRECIPITATION
DURING THE MORNING HOURS ON SUNDAY...BUT AS UPPER LOW CROSSES TO
OUR NORTH NEAR THE NORTH CAROLINA/VIRGINIA BORDER...THE STEEP
LAPSE RATES AND MODEST MOISTURE WILL LEAD TO A HIGH CHANCE OF
SHOWERS SUNDAY AFTERNOON. WITH GOOD COLD AIR ADVECTION...TEMPERATURES
WILL ONLY RECOVER ABOUT 5 TO 7 DEGREES AND WILL FOLLOW THE COOLER
NAM MOS GUIDANCE SUNDAY SHOWING HIGH TEMPERATURES IN THE LOW/MID
50S WITH GUSTY W/WNW WINDS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
AS OF 3 PM SAT...THE LONG TERM PORTION OF THE FORECAST CAN BE
SUMMARIZED AS DRYING OUT AND WARMING UP. MADE ONLY MINOR TWEAKS
TO THE POPS ENDING THE RAIN SUNDAY NIGHT. SURFACE/UPPER LOW AND
ASSOCIATED MOISTURE MOVE OFF TO THE NORTHEAST WITH RIDGING SURFACE
AND ALOFT BUILDING IN FROM THE WEST. RIDGING BEGINS TO BREAK DOWN
LATE IN THE WEEK AS AN UPPER LOW AND SURFACE COLD FRONT APPROACH
FROM THE WEST. THE COLD FRONT WILL MOVE THROUGH FRIDAY NIGHT AND
CARRIED A LOW CHANCE POP FOR SHOWERS AND STORMS. DRYING OUT
SATURDAY WITH THE FRONT OFF THE COAST AND A SURFACE HIGH BUILDING
TO THE NORTHWEST. NORTHWEST FLOW ON MONDAY WILL DIMINISH AND
SLOWLY TRANSITION TO A WEST TO SOUTHWEST FLOW BY TUESDAY NIGHT AND
CONTINUE INTO FRIDAY. HIGHS THIS WEEK WILL CLIMB WELL INTO THE
70S ACROSS MOST INLAND AREAS BEGINNING TUESDAY AS WINDS BECOME
SOUTHERLY.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
SHORT TERM /THROUGH 06Z MONDAY/...
AS OF 130 AM SUNDAY...CONDITIONS HAVE IMPROVED TO VFR ALL BUT KPGV
WHERE MVFR SCU STILL LINGERING. SCU VFR CIGS EXPECTED TO REDEVLOP
ALL SITES 09Z-12Z AS UPR LOW MOVES INTO AREA FROM W. LOWER MVFR CIGS
WILL DEVELOP WITH HEATING BY 15Z WITH SCT SHRA PSBL THROUGH AFTN AS
COLD CORE UPR LOW MOVES ACROSS NRN SECTIONS. CLEARING EXPECTED
DURING EVENING WITH LOSS OF HEATING. W WINDS WILL GUST UP TO 20-25
KT TODAY...DIMINISING AND BECOME NW THIS EVENING.
LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 3 PM SAT...IFR/MVFR CONDITIONS SUNDAY NIGHT WILL BECOME VFR
ON MONDAY AS MOISTURE EXITS TO THE NORTHEAST AND A SURFACE/UPPER
RIDGE BUILDS IN FROM THE WEST. NORTHWEST WINDS SUNDAY NIGHT AND
MONDAY WILL BECOME WEST TO SOUTHWEST TUESDAY NIGHT AND CONTINUE
THROUGH THURSDAY. MODEL SOUNDINGS INDICATE LATE NIGHT/EARLY
MORNING STRATUS/FOG POSSIBLE EACH MORNING WITH VERY LIGHT WINDS
AND BOUNDARY LAYER MOISTURE.
&&
.MARINE...
SHORT TERM /TONIGHT AND SUNDAY/...
AS OF 1230 AM SUNDAY...NO CHANGES WITH UPDATE.
/PREVIOUS DISCUSSION/
AS OF 920 PM SATURDAY...NO CHANGES TO PREVIOUS FORECAST THINKING
OTHER THAN TO EXTEND THE ADVISORIES FOR THE SOUNDS THROUGH EARLY
MONDAY. GUSTY SE/S WINDS WILL CONTINUE TONIGHT AND HAVE ADDED THE
ALBEMARLE SOUND TO THE SMALL CRAFT ADVISORY THAT WILL REMAIN IN
EFFECT UNTIL 5 AM SUNDAY. WILL INITIALIZE WINDS AT 20 TO 25 KNOTS
FOR ALL WATERS...EXCEPT 25 TO 30 KNOTS OVER THE OREGON INLET TO
OCRACOKE LEG WHERE WINDS CONTINUE TO BE STRONGEST. THESE WINDS
SHOULD SETTLE DOWN AFTER MIDNIGHT AS WINDS VEER TO MORE SW LATE.
PER LATEST NWPS WAVE MODEL...SEAS OF 9 TO 13 FEET WILL PREVAIL
OVER THE NORTHERN AND CENTRAL WATERS WITH GENERALLY 7 TO 10 FEET
OVER SOUTHERN PORTIONS...WITH A SLIGHT DROP IN THE MORE WESTERLY
FLOW EXPECTED DURING THE DAY ON SUNDAY.
LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 3 PM SAT...AN OVERALL IMPROVING TREND SEEN IN MARINE
CONDITIONS THROUGH THE LONG TERM. SURFACE/UPPER LOW WILL MOVE OFF
TO THE NORTHEAST SUNDAY NIGHT WITH SURFACE/UPPER RIDGE QUICKLY
BUILDING IN AND LINGERING FOR MOST OF THE WEEK. SMALL CRAFT
CONDITIONS WILL END FROM SOUTH TO NORTH MONDAY AND MONDAY NIGHT.
NORTHWEST FLOW SUNDAY NIGHT INTO MONDAY WILL BECOME WEST TO
SOUTHWEST TUESDAY NIGHT THROUGH THURSDAY.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT MONDAY FOR AMZ130-135.
SMALL CRAFT ADVISORY UNTIL 2 AM EDT TUESDAY FOR AMZ152-154.
SMALL CRAFT ADVISORY UNTIL 5 PM EDT MONDAY FOR AMZ156-158.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR AMZ150.
&&
$$
SYNOPSIS...CTC
NEAR TERM...CTC/JME/JBM
SHORT TERM...CTC
LONG TERM...HSA
AVIATION...JBM/HSA
MARINE...CTC/JME/HSA/JBM
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1240 AM EDT SUN MAR 30 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE OFFSHORE LATE TONIGHT. A SURFACE TROUGH WILL
LINGER JUST WEST OF THE AREA INTO MONDAY. WEAK HIGH PRESSURE BUILDS
OVER THE REGION MONDAY NIGHT AND TUESDAY. THE HIGH WILL MOVE SOUTH
OF THE AREA TUESDAY NIGHT AND WEDNESDAY. ANOTHER COLD WILL APPROACH
THE AREA BY LATE WEEK.
&&
.NEAR TERM /THROUGH SUNDAY/...
AS OF 1230 AM SUNDAY...UPDATED TO REDUCE POPS TO 30% FOR COASTAL
PLAINS OVERNIGHT AND 20% REST OF AREA. DRY SLOT WILL KEEP MOST OF
AREA DRY REST OF NIGHT BUT SCT SHOWERS WILL AFFECT COASTAL PLAINS
WITH CONVERGENCE JUST AHEAD OF FRONT. TORNADO WATCH WAS CANCELLED AT
10 PM. MINOR ADJUSTMENTS TO TEMPS AND SKY COVER.
/PREVIOUS DISCUSSION/
AS OF 920 PM SATURDAY...A TORNADO WATCH REMAINS IN EFFECT FOR THE
WESTERN PORTIONS OF EASTERN NC (MAINLY WEST OF HIGHWAY 17) UNTIL
1 AM. HAVE BEEN WATCHING A PERSISTENT SUPERCELL THUNDERSTORM WITH
A DEEP AND PERSISTENT MESCALINE MOVING THROUGH CENTRAL NC SINCE
730 PM. THIS STORM WILL REMAIN NW OF OUR AREA. TO THE SOUTH OF
THIS SYSTEM ADDITIONAL SHOWERS AND POSSIBLE THUNDERSTORMS WERE
DEVELOPING. THE HRRR MODEL BRINGS THIS CONVECTION INTO OUR PORTION
OF THE COASTAL PLAIN AROUND 11 PM SO WILL CONTINUE TO MONITOR. SO
FAR STORMS HAVE NOT WEAKENED WITH LOSS OF HEATING A SIGNAL THAT
THEY ARE BEING DYNAMICALLY FORCED. WILL CONTINUE TO KEEP POPS IN
THE CHANCE RANGE AS THE COVERAGE IN THE HIGH RESOLUTION MODELS
REMAINS SCATTERED. LATE TONIGHT DRY SLOTTING SHOULD END ANY
CHANCE OF PRECIPITATION UNTIL LATER SUNDAY WHEN THE UPPER LEVEL
LOW MOVES THROUGH. USED A BLEND OF THE ECMWF/MET MOS FOR LOWS WITH
READINGS IN THE UPPER 40S/LOWER 50S EXPECTED.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH 6 PM SUNDAY/...
AS OF 315 PM SATURDAY...WILL HAVE A BIT OF A LULL IN PRECIPITATION
DURING THE MORNING HOURS ON SUNDAY...BUT AS UPPER LOW CROSSES TO
OUR NORTH NEAR THE NORTH CAROLINA/VIRGINIA BORDER...THE STEEP
LAPSE RATES AND MODEST MOISTURE WILL LEAD TO A HIGH CHANCE OF
SHOWERS SUNDAY AFTERNOON. WITH GOOD COLD AIR ADVECTION...TEMPERATURES
WILL ONLY RECOVER ABOUT 5 TO 7 DEGREES AND WILL FOLLOW THE COOLER
NAM MOS GUIDANCE SUNDAY SHOWING HIGH TEMPERATURES IN THE LOW/MID
50S WITH GUSTY W/WNW WINDS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
AS OF 3 PM SAT...THE LONG TERM PORTION OF THE FORECAST CAN BE
SUMMARIZED AS DRYING OUT AND WARMING UP. MADE ONLY MINOR TWEAKS
TO THE POPS ENDING THE RAIN SUNDAY NIGHT. SURFACE/UPPER LOW AND
ASSOCIATED MOISTURE MOVE OFF TO THE NORTHEAST WITH RIDGING SURFACE
AND ALOFT BUILDING IN FROM THE WEST. RIDGING BEGINS TO BREAK DOWN
LATE IN THE WEEK AS AN UPPER LOW AND SURFACE COLD FRONT APPROACH
FROM THE WEST. THE COLD FRONT WILL MOVE THROUGH FRIDAY NIGHT AND
CARRIED A LOW CHANCE POP FOR SHOWERS AND STORMS. DRYING OUT
SATURDAY WITH THE FRONT OFF THE COAST AND A SURFACE HIGH BUILDING
TO THE NORTHWEST. NORTHWEST FLOW ON MONDAY WILL DIMINISH AND
SLOWLY TRANSITION TO A WEST TO SOUTHWEST FLOW BY TUESDAY NIGHT AND
CONTINUE INTO FRIDAY. HIGHS THIS WEEK WILL CLIMB WELL INTO THE
70S ACROSS MOST INLAND AREAS BEGINNING TUESDAY AS WINDS BECOME
SOUTHERLY.
&&
.AVIATION /01Z SUNDAY THROUGH THURSDAY/...
SHORT TERM /TONIGHT AND SUNDAY/...
AS OF 640 PM SATURDAY...SOME IFR CEILINGS ARE STILL BEING
REPORTED AT THE TAF SITES BUT THINK THE TREND IS FOR IMPROVEMENT
AS THE THREAT FOR WIDESPREAD PRECIPITATION IS OVER AND SOME DRYING
IS EXPECTED TO MOVE INTO THE AREA LATER THIS EVENING. BASED ON
UPSTREAM OBSERVATIONS AND TRENDS IN THE 12Z/18Z NAM FORECAST
SOUNDINGS WILL FORECAST CONDITIONS IMPROVING TO MVFR AND
CONTINUING FOR MUCH OF TONIGHT THEN A BRIEF PERIOD OF VFR
CONDITIONS AROUND 09Z DURING THE PEAK OF DRYING. AN UPPER LOW IS
FORECAST TO MOVE ACROSS NC SUNDAY. ASSOCIATED MOISTURE WILL LEAD
TO A RETURN TO MVFR CEILINGS 12-14Z WHICH WILL THEN PERSIST FOR
MUCH OF THE DAY. THERE COULD ALSO INTERMITTENT LIGHT RAIN OR
DRIZZLE AT TIMES. GUSTY SOUTHERLY WINDS TONIGHT WILL BECOME
WESTERLY ON SUNDAY.
LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 3 PM SAT...IFR/MVFR CONDITIONS SUNDAY NIGHT WILL BECOME VFR
ON MONDAY AS MOISTURE EXITS TO THE NORTHEAST AND A SURFACE/UPPER
RIDGE BUILDS IN FROM THE WEST. NORTHWEST WINDS SUNDAY NIGHT AND
MONDAY WILL BECOME WEST TO SOUTHWEST TUESDAY NIGHT AND CONTINUE
THROUGH THURSDAY. MODEL SOUNDINGS INDICATE LATE NIGHT/EARLY
MORNING STRATUS/FOG POSSIBLE EACH MORNING WITH VERY LIGHT WINDS
AND BOUNDARY LAYER MOISTURE.
&&
.MARINE...
SHORT TERM /TONIGHT AND SUNDAY/...
AS OF 1230 AM SUNDAY...NO CHANGES WITH UPDATE.
/PREVIOUS DISCUSSION/
AS OF 920 PM SATURDAY...NO CHANGES TO PREVIOUS FORECAST THINKING
OTHER THAN TO EXTEND THE ADVISORIES FOR THE SOUNDS THROUGH EARLY
MONDAY. GUSTY SE/S WINDS WILL CONTINUE TONIGHT AND HAVE ADDED THE
ALBEMARLE SOUND TO THE SMALL CRAFT ADVISORY THAT WILL REMAIN IN
EFFECT UNTIL 5 AM SUNDAY. WILL INITIALIZE WINDS AT 20 TO 25 KNOTS
FOR ALL WATERS...EXCEPT 25 TO 30 KNOTS OVER THE OREGON INLET TO
OCRACOKE LEG WHERE WINDS CONTINUE TO BE STRONGEST. THESE WINDS
SHOULD SETTLE DOWN AFTER MIDNIGHT AS WINDS VEER TO MORE SW LATE.
PER LATEST NWPS WAVE MODEL...SEAS OF 9 TO 13 FEET WILL PREVAIL
OVER THE NORTHERN AND CENTRAL WATERS WITH GENERALLY 7 TO 10 FEET
OVER SOUTHERN PORTIONS...WITH A SLIGHT DROP IN THE MORE WESTERLY
FLOW EXPECTED DURING THE DAY ON SUNDAY.
LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 3 PM SAT...AN OVERALL IMPROVING TREND SEEN IN MARINE
CONDITIONS THROUGH THE LONG TERM. SURFACE/UPPER LOW WILL MOVE OFF
TO THE NORTHEAST SUNDAY NIGHT WITH SURFACE/UPPER RIDGE QUICKLY
BUILDING IN AND LINGERING FOR MOST OF THE WEEK. SMALL CRAFT
CONDITIONS WILL END FROM SOUTH TO NORTH MONDAY AND MONDAY NIGHT.
NORTHWEST FLOW SUNDAY NIGHT INTO MONDAY WILL BECOME WEST TO
SOUTHWEST TUESDAY NIGHT THROUGH THURSDAY.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT MONDAY FOR AMZ130-135.
SMALL CRAFT ADVISORY UNTIL 2 AM EDT TUESDAY FOR AMZ152-154.
SMALL CRAFT ADVISORY UNTIL 5 PM EDT MONDAY FOR AMZ156-158.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR AMZ150.
&&
$$
SYNOPSIS...CTC
NEAR TERM...CTC/JME/JBM
SHORT TERM...CTC
LONG TERM...HSA
AVIATION...JME/HSA/LEP
MARINE...CTC/JME/HSA/JBM
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1145 PM CDT SAT MAR 29 2014
.UPDATE...
ISSUED AT 1145 PM CDT SAT MAR 29 2014
BUMPED UP CLOUD COVER A BIT...BUT NO OTHER BIG CHANGES TO THE
GOING FORECAST. WILL CONTINUE TO KEEP POPS IN THE 20-40 PERCENT
RANGE FOR SCATTERED SHOWERS MOVING ACROSS THE AREA. TEMPS CONTINUE
TO BE FAIRLY WARM WITH SOUTHERLY WINDS KEEPING READINGS UP.
UPDATE ISSUED AT 936 PM CDT SAT MAR 29 2014
MADE SOME ADDITIONAL TWEAKS TO POPS/WX. MOST OF THE RETURNS IN THE
NORTHERN CWA HAVE NOT YET BEEN REACHING THE GROUND...BUT ROLLA
JUST OUTSIDE THE CWA HAS STARTED REPORTING RAIN. CONTINUED TO KEEP
SOME 20-40 POPS IN THE NORTHERN COUNTIES AND ADJUSTED THEM A BIT
SOUTH TO COUNT FOR RADAR TRENDS TO OUR WEST AS WELL AS THE HRRR
AND RAP RUNS. CONTINUE TO THINK THAT SOUTH WINDS WILL KEEP TEMPS
UP AND TYPE AS RAIN FOR NOW.
UPDATE ISSUED AT 634 PM CDT SAT MAR 29 2014
MADE A FEW MINOR TWEAKS TO POPS ALONG THE NORTHERN BORDER...BUT NO
MAJOR CHANGES FOR THIS EVENING. THE CHANCE FOR A FEW RAIN SHOWERS
IN THE NORTH WILL CONTINUE AND SOUTH WINDS WILL CONTINUE TO KEEP
TEMPS UP.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 342 PM CDT SAT MAR 29 2014
FAIRLY QUIET THIS PERIOD AND MODELS IN DECENT AGREEMENT. VERY WARM
AIRMASS WILL PROPAGATE ACROSS THE REGION TONIGHT...WITH MIN TEMPS
AROUND THE FREEZING MARK. AN UPPER WAVE SHOULD BRING SCATTERED
SHOWERS NEAR THE INTERNATIONAL BORDER TONIGHT. ON SUNDAY...COLDER
AIRMASS BEGINS TO MOVE INTO THE WESTERN FA AS THE WINTER STORM TO
THE WEST ORGANIZES AND APPROACHES THE REGION.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 342 PM CDT SAT MAR 29 2014
SUNDAY NIGHT-TUESDAY...THE LARGE WINTER STORM IS STILL ON TRACK
TO HIT THE REGION (MOSTLY ON MONDAY). THE 12Z MODELS HAVE TRENDED
SLIGHTLY SLOWER (AND NORTHWARD WITH THE HEAVIEST SNOWFALL). THE
ECMWF REMAINS THE SLOWEST/FURTHEST NORTH...WHILE THE GFS IS
FURTHEST SOUTH WITH THE HEAVIEST SNOWFALL (BUT STILL WITHIN THE
FA). THE GEM/UKMET ARE SOMEWHERE IN THE MIDDLE...AND AT THIS
POINT MAKE THE MOST SENSE. THE NAM (ALTHOUGH SIMILAR WITH QPF) IS
THE FAST OUTLIER AND HAS BEEN DISCOUNTED. THE ECMWF IS ON THE
NORTHERN EDGE OF THE ENSEMBLE ENVELOPE...AND WOULD EXPECT THIS
SOLUTION TO TREND SLIGHTLY SOUTH WITH THE HEAVIEST QPF OVER THE
NEXT FEW MODEL RUNS. AT ANY RATE...THE INGREDIENTS ARE IN PLACE
FOR HEAVY SNOW SOMEWHERE...DEPENDING ON THE EXACT TRACK OF THIS
SYSTEM. AMOUNTS WITHIN THIS HEAVY SNOW AREA COULD AMOUNT TO A FOOT
OR MORE...WITH WIDESPREAD SNOWFALL OF 6 TO 12 INCHES APPEARING
LIKELY (THE NORTHERN AND SOUTHERN EDGE OF THIS SNOWFALL AREA WILL
BE CHALLENGING). THE SLOWER TREND OF THE MODELS HAS INCREASED THE
EXPECTED NORTHERLY WINDS ON MONDAY. NO MATTER WHICH MODEL SOLUTION
(EXCEPT THE FASTER NAM) YOU LOOK AT...ANTICIPATE SPEEDS AROUND 30
KNOTS GIVEN HIGH WIND INGREDIENTS AND MOS GUIDANCE. CONFIDENCE HAS
INCREASED IN BLIZZARD CONDITIONS SOMEWHERE WITHIN THE FA...AND
WILL `UPGRADE` THE WINTER STORM WATCH TO A BLIZZARD WATCH FOR THE
`MOST LIKELY` BLIZZARD AREA. DEFINITELY NOT ENOUGH CONFIDENCE FOR
A WARNING AT THIS POINT FOR ANY AREA AS THE EXACT TRACK AND SPEED
OF THE SYSTEM WILL ULTIMATELY AFFECT P-TYPE...SNOW AMOUNTS...AND
WIND SPEEDS.
TUE NIGHT THROUGH SAT...SFC HIGH PRESSURE MOVES OVER THE FA ON
TUE NIGHT KEEPING THINGS COOL AND DRY. BY WED THE FLOW TURNS MORE
TO THE SOUTHWEST WITH MODELS DIVERGING ON SOLUTIONS. THE 12Z GFS
IS QUICKER AND BRINGS IN LIGHT SNOW ON WED WHILE THE ECMWF/GEM
KEEP WED DRY. THESE DIFFERENCES CONTINUE INTO WED NIGHT WITH THE
GFS MOVING THE LIGHT SNOW INTO THE NE FA AND THE ECMWF/GEM STILL
NOT SHOWING MUCH OF ANYTHING. MORE POTENT SYSTEM LOOKING TO BE
THU/THU NIGHT ALTHOUGH STILL NOT MUCH AGREEMENT BETWEEN THE
MODELS. THE ECMWF SHOWS THE FURTHEST NORTH SOLUTION WHICH WOULD
GIVE ANOTHER BATCH OF SNOW TO THE SOUTHERN FA. THE GFS IS THE
FURTHEST SOUTH WITH THE WAVE WHILE THE GEM IS IN BETWEEN. WILL
LEAVE LOW SNOW CHANCES ACROSS MAINLY THE SOUTHERN FA FOR NOW AND
SEE IF MODELS COME INTO BETTER AGREEMENT LATER. TEMPS GENERALLY
LOOK TO STAY ON THE COOLER SIDE THROUGHOUT BUT COULD BE GREATLY
AFFECTED BY SNOW COVER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1145 PM CDT SAT MAR 29 2014
SOUTH WINDS HAVE CONTINUED TO BE A BIT MORE GUSTY THAN EXPECTED
BUT THINK THAT WINDS WILL DECREASE TOWARDS MORNING AS THE CENTER
OF THE SFC LOW MOVES INTO THE REGION. CONDITIONS WILL CONTINUE TO
BE VFR WITH CLOUDS AROUND 10000 FT. WINDS WILL SHIFT TO THE
NORTHWEST BY MID TO LATE MORNING. HAVE CIGS COMING DOWN...BUT KEPT
THE MVFR CONDITIONS OUT UNTIL LATE AFTERNOON OR EVENING. NORTH WINDS
WILL PICK UP MORE TO AROUND 20 KTS WITH HIGHER GUSTS LATE IN THE
PERIOD AS THE SFC LOW WRAPS UP. WILL ONLY GO WITH SOME -SN MENTION
AT KDVL FOR NOW AS THINK THAT MOST OF THE SIGNIFICANT SNOW WILL
NOT SET UP UNTIL LATE SUNDAY NIGHT.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...BLIZZARD WATCH FROM LATE SUNDAY NIGHT THROUGH LATE MONDAY NIGHT
FOR NDZ027>030-038-039-049-052-053.
WINTER STORM WATCH FROM LATE SUNDAY NIGHT THROUGH LATE MONDAY
NIGHT FOR NDZ008-016-024-026-054.
MN...BLIZZARD WATCH FROM LATE SUNDAY NIGHT THROUGH LATE MONDAY NIGHT
FOR MNZ001>003-029-030-040.
WINTER STORM WATCH FROM LATE SUNDAY NIGHT THROUGH LATE MONDAY
NIGHT FOR MNZ004>009-013>017-022>024-027-028-031-032.
&&
$$
UPDATE...JR
SHORT TERM...TG
LONG TERM...GODON/TG
AVIATION...JR
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
319 AM CDT SUN MAR 30 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 319 AM CDT SUN MAR 30 2014
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A DEEP TROUGH SOUTH OF THE GULF OF ALASKA...A VIGOROUS
SHORTWAVE TROUGH COMING INTO CENTRAL CALIFORNIA...AND A RIDGE AXIS
FROM TEXAS INTO THE FORECAST AREA. PROFILER AND VAD WIND DATA SHOWED
A CORRIDOR OF SOUTHWESTERLY 40-55 KT WINDS AT 925MB JUST TO THE WEST
OF THE RIDGE AXIS. THESE WINDS ARE PROPELLING WARMER AIR THAT WAS
OBSERVED OVER THE PLAINS YESTERDAY TOWARDS THE FORECAST AREA. ITS
WORTH NOTING HIGHS YESTERDAY WERE IN THE 60S TO LOW 70S FROM WESTERN
NORTH DAKOTA INTO OKLAHOMA...ASSOCIATED WITH 925MB TEMPS OF 10 TO
20C. CLOUD COVER MOSTLY OF THE SCATTERED CIRRUS VARIETY...REFLECTIVE
OF UPPER LEVEL MOISTURE STREAMING FROM THE PACIFIC ON WATER VAPOR.
AIRMASS ACROSS MUCH OF THE PLAINS AND THE FORECAST AREA VERY DRY PER
00Z SOUNDINGS...NOTED TOO FROM PRECIPITABLE WATER VALUES BETWEEN 0.2-
0.3 INCHES. AT THE SURFACE...THE SURFACE RIDGE THAT WAS OVER THE
AREA YESTERDAY HAS SHIFTED EAST TO OVER LAKE MICHIGAN...WHILE
PRESSURES ARE FALLING ALONG THE LEE OF THE ROCKIES. THE SURFACE
RIDGE HAS PUSHED ANY MEANINGFUL SURFACE MOISTURE...DEWPOINTS AT OR
ABOVE 40F...DOWN TO THE GULF OF MEXICO COAST.
SYNOPTICALLY...THE UPPER RIDGING PRESENT OVER THE FORECAST AREA
LOOKS TO PERSIST THROUGH TONIGHT...WITH A SHIFT TO THE EAST AFTER
MIDNIGHT. THE PUSH EAST TO THE RIDGE IS CAUSED BY THE VIGOROUS
SHORTWAVE LIFTING INTO THE FAR NORTHEAST COLORADO AREA BY 12Z
MONDAY. ITS ALSO WORTH NOTING THAT THE SHORTWAVE BECOMES NEGATIVELY
TILTED.
WITH THE FORECAST AREA PROGGED TO BE IN THE WARM SECTOR OF A
DEEPENING LOW COMING OUT OF COLORADO AND INTO CENTRAL NEBRASKA BY
12Z MONDAY...MUCH OF THE FORECAST CONCERN IS ON TEMPERATURES. 925MB
TEMPS ARE PROGGED TO CONTINUE TO CLIMB THROUGH THE DAY ON A BREEZY
SOUTH TO SOUTHWEST WIND...RISING FROM 1 TO 5C AT 12Z TO 9 TO 13C BY
00Z. THESE READINGS HOLD NEARLY STEADY FOR TONIGHT DUE TO PERSISTENT
25-35 KT SOUTH WINDS. COMBINATION OF THE AFOREMENTIONED WARM
ADVECTION AND SUNSHINE SHOULD EASILY PUSH HIGHS INTO THE 60S ALONG
AND SOUTHWEST OF I-94. NORTH OF I-94...SNOW PACK AND COOLER 925MB
TEMPS WILL HOLD HIGHS BACK INTO THE 50S. THE MIXING TODAY TOO WILL
BE LIMITED A LITTLE DUE TO SCT-BKN CIRRUS EMANATING FROM NEBRASKA
AREA CURRENTLY. WITH A LOW LEVEL JET IN PLACE TONIGHT...MOST
LOCATIONS SHOULD ONLY SEE LOWS IN THE 40S. THERE ARE INDICATIONS THE
TYPICAL COLD SPOTS MIGHT DECOUPLE OR AT LEAST SEE LIGHTER
WINDS...ALLOWING TEMPERATURES THERE TO DIP INTO THE UPPER 30S.
PRECIPITATION-WISE...PLENTIFUL DRY AIR IN PLACE AS SEEN AT 00Z LAST
EVENING WILL KEEP CONDITIONS DRY THROUGH THIS EVENING. AFTER
MIDNIGHT...THERE IS GOOD AGREEMENT AMONG MODELS FOR A WARM CONVEYOR
BELT OF PRECIPITATION TO DEVELOP OVER EASTERN NEBRASKA AND WESTERN
IOWA. MUCH OF THIS PRECIPITATION CORRELATES WITH ISENTROPIC LIFT ON
THE 305-310K SURFACES...OR AT PRESSURES ABOVE 700MB. IN ANY
EVENT...AT LEAST THROUGH TONIGHT...THE FORECAST AREA STAYS DRY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 319 AM CDT SUN MAR 30 2014
MUCH OF THE FOCUS IS ON THE MONDAY THROUGH TUESDAY PERIOD. IMPACTS
DESCRIBED BELOW...
SYNOPTICALLY...ATTENTION IS COMPLETELY ON THE VIGOROUS SHORTWAVE
TROUGH APPROACHING THE CENTRAL CALIFORNIA COAST. MODELS CONTINUE TO
CONVERGE ON A COMMON SOLUTION FOR HANDLING THIS NEGATIVE TILT
TROUGH...THOUGH THERE IS SOME SLIGHT TIMING SPREAD. MODEL CONSENSUS
SHOWS THE TROUGH LIFTING INTO SOUTHWEST MN BY 00Z TUESDAY...
NORTHWEST WI BY 12Z TUESDAY AND INTO ONTARIO BY 00Z WEDNESDAY. THE
NAM REMAINS THE FASTEST OF THE CONSENSUS AND SEEMS A LITTLE
SUSPICIOUS...SEEING THAT THE ECMWF HAS BEEN TRENDING SLOWER OVER THE
PAST FEW DAYS. GIVEN THE VIGOROUS NATURE OF THE SHORTWAVE...WOULD
SEEM A SLOWER AND DEEPER ROUTE WOULD BE THE WAY TO GO. REGARDING
THE SURFACE LOW...FOLLOWING THE SAME PREMISES...BELIEVE THE
SLOWER...DEEPER MORE WRAPPED SYSTEM PRESENTED BY THE
CANADIAN/UKMET/ECMWF IS MORE LIKELY COMPARED TO THE NAM AND EVEN
GFS. WPC HAS ALSO FAVORED THE SAME MODELS.
PRECIPITATION-WISE...THE WARM CONVEYOR BELT DEVELOPING OFF TO OUR
WEST LOOKS LIKELY TO MOVE INTO WESTERN PORTIONS OF THE FORECAST AREA
MONDAY MORNING. HARD TO SAY IF IT IS GOING TO PROGRESS INTO
WISCONSIN PRIOR TO 18Z SEEING THE DRIER NAM/ECMWF LOOK. THEREFORE
HAVE ONLY KEPT 20-40 PERCENT CHANCES 15-18Z. FOR THE AFTERNOON...
THERE ARE SIGNS THAT THE WARM CONVEYOR PRECIPITATION MAY FALL APART
AS IT MOVES INTO WISCONSIN...OR AT LEAST SHIFT NORTH INTO NORTHERN
WISCONSIN....ESPECIALLY IN THE CANADIAN MODELS. GFS 305-310K
ISENTROPIC LIFT PROGS SUGGEST THE SAME. THEREFORE...HAVE KEPT
PRECIPITATION CHANCES MOSTLY IN THE 20-50 PERCENT RANGE OUTSIDE
OF TAYLOR COUNTY WHERE PRECIPITATION IS MOST LIKELY. FOCUS THEN
SHIFTS WEST ON WHETHER SHOWERS OR STORMS CAN FIRE ALONG A COLD
FRONT / DRY LINE. THE GFS/CANADIAN/ECMWF/UKMET ALL INITIATE A SCT-
BKN LINE OF SHOWERS NEAR I-35 TOWARDS 00Z. HOWEVER...THERE ARE TWO
HUGE CONCERNS FOR THIS BEING A LINE OF SURFACE BASED CONVECTION...
FIRST IS A FAIRLY STOUT CAP AROUND 700MB...SECOND ARE SURFACE
DEWPOINTS WHICH MODELS TRY TO JUMP INTO THE LOW 50S. THE DEWPOINTS
SEEM WAY OVERDONE. NOW CANT RULE OUT THE LINE OF SHOWERS FORMING
MORE ABOVE THE CAP GIVEN FORCING FROM THE LEFT EXIT REGION ALONG
WITH DPVA WITH THE TROUGH. SINCE THERE IS NO CAPE ABOVE THE CAP
AND CONCERNED PRECIPITATION MAY NOT FORM AT ALL...REMOVED THE
THUNDER CHANCE. THIS SHOULD ALSO REDUCE THE CONCERN OF ANY
POSSIBLE SEVERE WEATHER. IF A LINE DOES FORM...IT LOOKS TO LIFT
NORTHEAST THROUGH THE AREA DURING THE EVENING. PRECIPITATION LOOKS
MORE LIKELY AFTER MIDNIGHT INTO TUESDAY MORNING OVER THE NORTHWEST
HALF OF THE AREA AS THE COLD CONVEYOR BELT WRAPS IN. MOST OF THIS
SHOULD BE A LIGHT SNOW WITH LITTLE ACCUMULATION. THIS SNOW WILL
TAPER OFF TUESDAY AFTERNOON WITH THE DEPARTURE OF THE SYSTEM.
TEMPERATURES...BEING IN THE WARM SECTOR ALL OF MONDAY WITH 9-13C
925MB READINGS...COMBINED WITH A WARMER START...THAT BREAK IN
PRECIPITATION DURING THE AFTERNOON TO ALLOW FOR MIXING AND BREEZY
SOUTH WINDS...HIGHS AGAIN SHOULD CLIMB INTO THE 60S AT MOST
LOCATIONS. SNOWPACK HOLDS TAYLOR DOWN INTO THE 50S. READINGS THEN
TANK MONDAY NIGHT AS THE COLD AIR WRAPS IN SOUTHWEST TO NORTHEAST.
MUCH COOLER HIGHS FOR TUESDAY...THOUGH SOUTHERN AREAS SHOULD CLIMB
INTO THE MID 40S AS THE COLD AIR DEPARTS.
WINDS...SOUTHERLY 925MB WINDS INCREASE THROUGH MONDAY AS THE
NEGATIVE TILT SHORTWAVE TROUGH APPROACHES. BY 21Z...MOST MODELS PROG
THEM AROUND 40 KT WHILE 850MB WINDS APPROACH 50-55 KT...STRONGEST
SOUTH OF I-90. DAYTIME MIXING SHOULD BE ENOUGH TO GIVE GUSTS OF 30-
35 KT...WITH A PRESSURE FALL CROSSING EAU CLAIRE GIVING SOME
ISALLOBARIC HELP. AN ADVISORY MAY BE NEEDED IF NAM/GFS MOMENTUM
TRANSFER PROGS ARE CORRECT...SUGGESTING 35-42 KT GUSTS. WITH THE
COLD SIDE OF THE SYSTEM...925MB WINDS ARE A LITTLE LESS...CLOSER TO
35 KT FOR MONDAY NIGHT INTO TUE MORNING. THESE SHOULD EASILY MIX TO
THE GROUND. MORE UNCERTAINTY EXISTS ON THE NEED FOR THE ADVISORY ON
THE COLD SIDE.
FOR TUESDAY NIGHT AND BEYOND...
NEXT ITEM OF INTEREST IS THE TROUGH CURRENTLY SOUTH OF THE GULF OF
ALASKA WHICH IS PROGGED TO END UP IN THE SOUTHWESTERN U.S. ON
WEDNESDAY. UPPER RIDGING BUILDS DOWNSTREAM AHEAD OF THE TROUGH...BUT
MOSTLY SOUTH OF THE FORECAST AREA. THIS KEEPS A COLDER LOW LEVEL
AIRMASS IN PLACE. MEANWHILE...ISENTROPIC LIFT OF GULF OF MEXICO
MOISTURE DOWNSTREAM OF THE UPPER TROUGH MAY SPREAD SOME
PRECIPITATION INTO SOUTHERN PORTIONS OF THE FORECAST AREA PER 30.00Z
GFS/GFS ENSEMBLES WEDNESDAY AND WEDNESDAY NIGHT. HOWEVER...30.00Z
CANADIAN AND ECMWF KEEP THE PRECIPITATION SOUTH OF THE FORECAST
AREA. HAVE SPLIT THE DIFFERENCE WHICH RESULTS IN MAINLY A DRY
FORECAST NORTH OF I-90 TO SOME 20-50 PERCENT CHANCES SOUTH. THURSDAY
COULD END UP BEING A MOSTLY DRY DAY. CONFIDENCE IS BEGINNING TO
INCREASE FOR PRECIPITATION THURSDAY NIGHT THROUGH FRIDAY. THIS IS
WHEN MODELS ARE IN GOOD AGREEMENT LIFTING THE TROUGH INTO THE
FORECAST AREA. WINTER WEATHER ADVISORIES REMAIN POSSIBLE...MOSTLY
DUE TO ACCUMULATING SNOW. DRIER WEATHER LOOKS TO MOVE IN FOR
SATURDAY AS THE SYSTEM DEPARTS. BELOW NORMAL TEMPERATURES ARE LIKELY
FOR MUCH OF TUESDAY NIGHT AND BEYOND GIVEN THE UPPER FLOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1132 PM CDT SAT MAR 29 2014
THE MAIN FOCUS AT THE TAF SITES IS WITH THE WINDS. THE LOW LEVEL
PRESSURE GRADIENT WILL TIGHTEN UP OVERNIGHT INTO TOMORROW MORNING
AS A LOW PRESSURE SYSTEM TRACKS INTO SOUTHERN CANADA. SOME STRONG
LOW LEVEL WINDS LOOK LIKE THEY WILL GET INTO RST OVERNIGHT WITH
SOME 50KT WINDS AROUND 1.5KFT. OTHERWISE...WINDS WILL BECOME GUSTY
SUNDAY MORNING INTO THE EARLY AFTERNOON WITH GUSTS INTO THE 20 TO
30KT RANGE. AS THE GRADIENT RELAXES IN THE AFTERNOON...THE WINDS
WILL START TO SUBSIDE. CLOUD COVER LOOKS FAIRLY MINIMAL AND MAINLY
ABOVE 15KFT.
&&
.HYDROLOGY...
ISSUED AT 319 AM CDT SUN MAR 30 2014
BASED ON GAUGE READINGS ALONG THE KICKAPOO FOR THOSE THAT STILL HAVE
FLOOD WARNINGS...CONFIDENCE IS DECREASING THAT THEY WILL MAKE IT TO
FLOOD. READSTOWN HAS STARTED FALLING...WHEN IT SHOULD STILL BE
RISING. IF TRENDS CONTINUE...THE WARNINGS MAY BE CANCELLED.
FOCUS THEN SHIFTS TO THE BLACK...BUFFALO AND TREMPEALEAU RIVERS. THE
WARM UP OCCURRING TODAY AND PERSISTING INTO MONDAY EVENING...
FEATURING HIGHS IN THE 55-65 RANGE AND LOWS IN THE 38-48 RANGE ALONG
WITH BREEZY SOUTH WINDS...WILL HELP RAPIDLY MELT THE SNOW PACK THAT
IS IN PLACE ALONG AND NORTH OF HIGHWAY 10. THIS RUNOFF WILL MAKE
FLOODING A POSSIBILITY DURING THE WEEK. ON A POSITIVE NOTE...THE
PRECIPITATION FROM THE SYSTEM MOVING THROUGH THE AREA MONDAY AND
MONDAY NIGHT CONTINUES TO LOOK LESS AND LESS. AT THIS POINT...RAIN
DOES NOT APPEAR TO BE MUCH OF A FACTOR TO THE RIVERS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...HALBACH
HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1127 AM EDT SUN MAR 30 2014
.SYNOPSIS...
ISSUED AT 309 AM EDT SUN MAR 30 2014
HIGH PRESSURE WILL REMAIN IN CONTROL OF THE WEATHER THROUGH
MONDAY...BRINGING PLENTY OF SUNSHINE AND INCREASINGLY WARMER
TEMPERATURES. A FRONT CROSSING THE REGION LATE MONDAY NIGHT AND
EARLY TUESDAY WILL BRING A CHANCE FOR SOME LIGHT SHOWERS...ALONG
WITH A RETURN TO COOLER WEATHER. RAIN MAY MIX WITH...OR EVEN CHANGE
OVER...TO A BIT OF SNOW ON TUESDAY...BUT NO ACCUMULATIONS ARE
EXPECTED. COOL WEATHER WILL CONTINUE FOR THE MIDDLE AND END PORTIONS
OF THE WEEK...WITH ANOTHER CHANCE FOR A WINTRY MIX OF PRECIPITATION
THURSDAY AND FRIDAY.
&&
.UPDATE...
ISSUED AT 1125 AM EDT SUN MAR 30 2014
HIGH PRESSURE SURFACE AND ALOFT WILL ENSURE A NICE AFTERNOON FOR
NORTHERN MICHIGAN WITH JUST A FEW CLOUDS DRIFTING BY. WIDESPREAD
HIGHS IN THE 40S EXPECTED.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 309 AM EDT SUN MAR 30 2014
HIGH IMPACT WEATHER POTENTIAL: NONE.
PATTERN SUMMARY: AN EARLY MORNING LOOK AT THE PATTERN ACROSS THE
CONUS REVEALS AN ACTIVE SETUP...WITH LOW PRESSURE SYSTEMS ALONG BOTH
COASTS...AND A NARROW RIDGE OF HIGH PRESSURE IN BETWEEN THESE
SYSTEMS... ARCHING FROM QUEBEC...THROUGH THE GREAT LAKES AND DOWN
THE MISSISSIPPI VALLEY. THIS RIDGE AXIS CURRENTLY LIES JUST WEST OF
THE FORECAST AREA...WITH A RIBBON OF CLEARING ALLOWING LOW
TEMPERATURES TO FALL RAPIDLY AS BOUNDARY LAYER WINDS DECOUPLE.
LOOKING FORWARD THROUGH THE SHORT TERM FORECASTS REQUIRES US TO LOOK
UPSTREAM...AND...SOMEWHAT DIFFERENTLY THAN WE HAVE SEEN OF
LATE...MUCH OF WHAT IS UPSTREAM IS DOMINATED BY PACIFIC...MARITIME
POLAR AIR...WITH ANY ARCTIC AIR NOW BOTTLED UP NORTH OF THE REGION.
THIS PACIFIC FLOW WILL RESULT IN LEE-SIDE CYCLOGENESIS EAST OF THE
ROCKIES DURING THE DAY TODAY...WITH THIS LOW PRESSURE DEEPENING AND
BEGINNING TO DEPART TO THE NORTH AND EAST BY THE END OF THIS PERIOD
AROUND DAYBREAK MONDAY. THE DOWNSTREAM LONGWAVE TROUGH IS MUCH
SLOWER MOVING...AND THE DEVELOPING SQUEEZE PLAY IN BETWEEN THESE
FEATURES WILL FORCE HEIGHTS TO BUILD OVER THE GREAT LAKES WITH QUIET
AND MODERATING CONDITIONS EXPECTED FOR NORTHERN MICHIGAN. CERTAINLY
A WELCOME REPRIEVE FROM AN EXCEPTIONALLY COLD MONTH OF MARCH.
THROUGH DAYBREAK: TEMPERATURES WILL CONTINUE TO TUMBLE THROUGH THE
TEENS GIVEN CLEAR SKIES AND CALM-LIGHT WINDS. ALSO CAN/T RULE OUT
SOME PATCHY GROUND FOG GIVEN IMPRESSIVE OVERNIGHT COOLDOWN.
TODAY: RIDGE AXIS WILL BE PRETTY MUCH OVERHEAD TO START THE
DAY...GRADUALLY SHIFTING EAST TO A POSITION OVER LAKE HURON
TOWARDS EVENING. THERE/S A RELATIVE LACK OF MOISTURE THROUGH THE
COLUMN TO START THE DAY WITH PWATS SUB 0.25" /A LITTLE BELOW
SEASONAL NORMS FOR LATE MARCH/ WITH VALUES INCREASING DURING THE DAY
AS A CHUNK OF PACIFIC MOISTURE /SEEN NOW AS A PLUME OF DEEP MOISTURE
ACROSS THE NORTHWESTERN QUARTER OF THE COUNTRY/ RIDES EAST. WHILE
THIS COULD MANIFEST ITSELF AS SOME HIGH CLOUDS FOR THE NORTHERN HALF
OF THE CWA /ESP FOR THE SECOND HALF OF THE DAY/...THE LACK OF LLEVEL
MOISTENING BENEATH BUILDING MID LEVEL HEIGHTS SUGGESTS NO REAL
POTENTIAL FOR CU DEVELOPMENT. THUS...EXPECT ABUNDANT SUNSHINE FOR
THE AREA WITH NO SENSIBLE WEATHER CONCERNS.
TEMPERATURES /CONFIDENCE: HIGH/:
TRAJECTORY ANALYSIS PLACES THIS AFTERNOON/S AIRMASS OVER SOUTHERN
MINNESOTA 24 HOURS PREVIOUS WITH T9S SURGING TO 0-3C BY LATE
AFTERNOON UNDER STRONG WARM ADVECTION. WITH BUILDING HEIGHTS AND
NEARBY RIDGE AXIS...MIXING ISN/T GOING TO BE TOO STRONG. LOOKING
BACK TO MINNESOTA...AREAS THAT WERE UNABLE TO MIX DEEPLY REACHED THE
LOWER 40S...WITH UPPER 40S FURTHER WEST WHERE MECHANICAL MIXING
COMBINED WITH WARMER TEMPS ALOFT TO BOOST SURFACE TEMPS. EXPECT
THAT WE/LL BE CLOSER TO THE FORMER TODAY...AND EXPECT HIGHS IN THE
40-45 DEGREE RANGE. AMAZINGLY...THAT WILL PUT US JUST ABOUT WHERE
WE SHOULD BE FOR THE END OF MARCH.
AS MENTIONED BY THE PREVIOUS DAYSHIFT...LIGHT FLOW REGIME AND
SOMEWHAT WARMER TEMPERATURES SHOULD ALLOW FOR SOME LAKE BREEZE
DEVELOPMENT...KEEPING HIGHS LOCALLY COOLER ALONG THE LAKE HURON
COAST.
TONIGHT: RIDGE CONTINUES TO PUSH EAST OF THE GREAT LAKES
REGION...WITH NORTHERN STREAM COLD FRONT STALLING NEAR LAKE SUPERIOR
AS LOW PRESSURE ALONG THE EAST SLOPES OF THE ROCKIES BEGINS TO
DEPART AND HEAD NORTHEAST. MOISTURE CONTINUES TO SLOWLY
INCREASE...BUT PRIMARILY AT UPPER LEVELS WITH TOP-DOWN SATURATION
LIKELY ONLY YIELDING AN INCREASE IN UPPER LEVEL CLOUDS THROUGH THE
OVERNIGHT. GRADIENT STRENGTHENS THROUGH THE NIGHT...WITH MOST
LOCATIONS RE-COUPLING DURING THE OVERNIGHT. SEE NO REPEAT OF ANY
FOG GIVEN BETTER LLEVEL MIXING AND CONTINUED DRY LLEVEL CONDITIONS.
TEMPERATURES /CONFIDENCE: MODERATE-HIGH/:
TEMPERATURES WILL BE A LITTLE COMPLEX WITH EVENING MCLEAR SKIES AND
DECOUPLING LIKELY TO GIVE WAY TO INCREASED MIXING AS THE NIGHT GOES
ON. THIS WILL YIELD LOWS COLDEST OVER NORTHEAST LOWER WITH LOWS
LIKELY TO DIP TO AROUND 20 /AND PERHAPS A TAD BELOW THIS/...WITH
TEMPS OVER NORTHWEST LOWER STRUGGLING TO FALL MUCH BELOW THE
FREEZING MARK.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 309 AM EDT SUN MAR 30 2014
...REAL SPRING "WARMTH" GIVES WAY TO BELOW NORMAL TEMPERATURES (GO
FIGURE)...
HIGH IMPACT WEATHER POTENTIAL: WATCHING WINTRY PRECIP THREAT LATER
IN THE WEEK.
OVERVIEW: PATTERN REMAINS AN AGITATED ONE...WITH EXTENDED AMPED
PACIFIC REGIME OVER THE CONUS TUCKED NICELY ON SOUTH SIDE OF WELL
DEVELOPED NORTH CANADA COLD CORE GYRE. PACIFIC PATTERN CONTINUES TO
WIN OUT OVER NORTHERN MICHIGAN...WITH STEADY RETREAT OF OVERHEAD
COLD AIRMASS AS AGGRESSIVE UPSTREAM WARMING BEGINS. 00Z RAOB/HIGH
RES RAP GUIDANCE CONFIRMS SUCH...SHOWING H8 TEMPERATURES SPIKING
INTO THE TEENS (THAT`S ABOVE ZERO FOLKS!) ACROSS THE HIGH
PLAINS...WITH ABOVE ZERO H8 AIR ALREADY ADVANCING TO THE MISSISSIPPI
RIVER. EXPECTED RATHER SUBSTANTIAL UPPER MISSISSIPPI VALLEY LOW
PRESSURE DEVELOPMENT EARLY THIS WORK WEEK WILL ONLY HELP THE
NORTHERN LAKES WARMING CAUSE...WITH MUCH OF THE AREA TO FALL
SQUARELY IN THE WARM SECTOR OF THIS SYSTEM AS IT TRACKS TO OUR
NORTHWEST. UNFORTUNATELY...COOL AIR WILL BE FORCED SOUTH ON ITS
BACKSIDE...ONCE AGAIN DROPPING TEMPERATURES TO BELOW NORMAL LEVELS
AS WE HEAD THROUGH THE MID AND AND PORTIONS OF NEXT WEEK. PACIFIC
WAVE TRAIN REMAINS...AT LEAST SETTING UP SOME POTENTIAL FOR BOUTS OF
MORE WINTRY WEATHER HEADING INTO THURSDAY AND FRIDAY. OH...THE
JOY!
PRIMARY FORECAST CONCERNS/CHALLENGES: PLENTY! TEMPERATURE TRENDS
THROUGHOUT...PRECIP TIMING/AND EVENTUAL TYPE...HEADING THROUGH NEXT
WORK WEEK.
DETAILS: JUST HOW WARM TO GO ON MONDAY? ABOUT TEXTBOOK END OF
MARCH/BEGINNING OF APRIL SPRING STORM WILL BE UNDERGOING FULL
DEVELOPMENT ACROSS THE CENTRAL PLAINS EARLY MONDAY...EXPECTED TO
PASS SOMEWHERE VICINITY CENTRAL/WESTERN UPPER MICHIGAN TUESDAY.
STRONG DOWNSTREAM OFF THE DECK WAA EXPECTED...WITH NOW MULTI-DAY
PROGS SUPPORTING H8 READINGS SPIKING TO NEAR 10C BY LATER MONDAY
OVER NORTHERN MICHIGAN. WITH ELEVATED WARM FRONT ALREADY NORTH OF
THE AREA...AND CORE OF MID LEVEL DYNAMICS WELL OFF TO OUR
WEST...WOULD EXPECT PLENTY OF SUNSHINE TO FURTHER KICK THE WARMING
INTO OVERDRIVE. INCREASINGLY DEEP MIXED LAYER/FORCED MECHANICAL
MIXING PER INCREASING WINDS SHOULD ALLOW SURFACE TEMPERATURES TO
RESPOND ACCORDINGLY...AND REALLY LIKE INHERITED HIGHS WILL INTO THE
50S/NEAR 60 OVER NORTHERN LOWER MICHIGAN. SOUTHEAST LOW LEVEL FLOW
WILL KEEP NORTHEAST LOWER AND EASTERN UPPER MICHIGAN SEVERAL DEGREES
COOLER. MILD AIR CONTINUES INTO MONDAY NIGHT AS SOUTH FLOW
REMAINS...AND FEEL SOME AREAS MAY FAIL TO FALL OUT OF THE 40S. DRY
WEATHER GIVES WAY TO INCREASING SHOWER CHANCES MONDAY NIGHT AS
OCCLUDED FRONT INTERACTS WITH NARROW BAND OF ENHANCED DEEP LAYER
MOISTURE. STRONGEST AND DEEPEST DYNAMICS REMAIN TO OUR
NORTHWEST...WHERE HEAVIEST AND STEADIEST PRECIPITATION SHALL RESIDE.
BACK TO 2014 SPRING NORMALCY QUICKLY ON TUESDAY AS SURGE OF COLDER
AIR FOLLOWS PASSAGE OF OCCLUDED FRONT. MORNING HIGH TEMPERATURES IN
THE 30S AND 40S WILL SLOWLY FALL THROUGH THE AFTERNOON ON GUSTY
SOUTHWEST TO WEST WINDS. LIGHT RAIN/SNOW SHOWERS TRANSITION TO
MAINLY SNOW AS COLD AIR DEEPENS AND SYSTEM BACKSIDE MOISTURE
REMAINS. JUST MINIMAL...IF ANY...ACCUMULATION IS EXPECTED.
UNCERTAINTY THE NAME OF THE GAME HEADING INTO THE MID AND END
PORTIONS OF THE WEEK. QUESTIONS ARE MANY CONCERNING NEXT WAVE
EXPECTED TO EJECT OUT OF THE INTERMOUNTAIN WEST. INTERACTION BETWEEN
SOUTHERN CANADA HIGH/ASSOCIATED DRY AIR FEED AND WHAT SHOULD BE
RATHER VIGOROUS MID LEVEL WAVE LEADING TO RATHER SIGNIFICANT
DISCREPANCIES AMONGST MID RANGE GUIDANCE. ECMWF REMAINS MOST
ROCK-STEADY...SUGGESTING A MORE AMPED AND FURTHER NORTH SOLUTION
WITH LOW PRESSURE MOVING DIRECTLY ACROSS THE GREAT LAKES TO END THE
WORK WEEK. OTHER GUIDANCE STARTING TO FALL IN LINE WITH THIS MORE
NORTH/AMPED SOLUTION...ALTHOUGH HONESTLY...THIS DOES LITTLE TO
INCREASE CONFIDENCE AS A MORE SOUTH DISPLACED SYSTEM IS FULLY
PLAUSIBLE GIVEN EXPECTED SET-UP AND POTENTIAL FOR A STRONGER
CANADIAN HIGH. TEMPERATURE PROFILE REMAINS MARGINALLY SUPPORTIVE OF
A MIXED PRECIP EVENT IF FURTHER NORTH SOLUTIONS VERIFY. SET-UP ALSO
HAS SOME INTRIGUING FREEZING RAIN POSSIBILITIES...WITH POTENTIAL FOR
MAINTENANCE OF DRY AND COLD EAST FLOW TO MAINTAIN SUB-FREEZING
SURFACE TEMPERATURES...ALL THE WHILE ELEVATED WARM NOSE DEEPENS. OF
COURSE...MUCH TOO FAR OUT TO SHOW SUCH SPECIFICS...ESPECIALLY
CONSIDERING UNCERTAINTY IF SYSTEM WILL EVEN DIRECTLY AFFECT OUR
AREA. LITTLE CHOICE BUT TO RUN WITH A GENERIC RAIN/SNOW CHANCE
WORDING FOR NOW...WITH PLENTY OF TIME TO FINE-TUNE DETAILS IN
COMING DAYS. WHILE EXCEPTIONALLY COLD AIR NOW LOOKS LIKE A THING OF
THE PAST...OVERALL TRENDS FAVOR BELOW NORMAL TEMPERATURES WEDNESDAY
THROUGH NEXT WEEKEND...WITH HIGHS MOSTLY IN THE 30S AND LOWER
40S/OVERNIGHT LOWS IN THE 20S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 635 AM EDT SUN MAR 30 2014
UNRESTRICTED CONDITIONS EXPECTED AT ALL TAF SITES THROUGH THE
DURATION. ONLY SCT/BKN HIGH LEVEL CLOUDS. LIGHT SOUTH/SOUTHEAST
SURFACE WINDS EXPECTED TODAY ACROSS WESTERN TAF SITES...WITH A LAKE
INDUCED MORE EASTERLY COMPONENT AT KAPN. LIGHT/CALM WINDS
OVERNIGHT. LOW LEVEL JET INTENSIFIES TONIGHT...PRODUCING LLWS AT
ALL SITES EXCLUDING KAPN.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...JPB
SYNOPSIS...MSB
SHORT TERM...ARNOTT
LONG TERM...MSB
AVIATION...MSB
AREA FORECAST DISCUSSION
NWS GAYLORD MI
639 AM EDT SUN MAR 30 2014
.SYNOPSIS...
ISSUED AT 309 AM EDT SUN MAR 30 2014
HIGH PRESSURE WILL REMAIN IN CONTROL OF THE WEATHER THROUGH
MONDAY...BRINGING PLENTY OF SUNSHINE AND INCREASINGLY WARMER
TEMPERATURES. A FRONT CROSSING THE REGION LATE MONDAY NIGHT AND
EARLY TUESDAY WILL BRING A CHANCE FOR SOME LIGHT SHOWERS...ALONG
WITH A RETURN TO COOLER WEATHER. RAIN MAY MIX WITH...OR EVEN CHANGE
OVER...TO A BIT OF SNOW ON TUESDAY...BUT NO ACCUMULATIONS ARE
EXPECTED. COOL WEATHER WILL CONTINUE FOR THE MIDDLE AND END PORTIONS
OF THE WEEK...WITH ANOTHER CHANCE FOR A WINTRY MIX OF PRECIPITATION
THURSDAY AND FRIDAY.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 309 AM EDT SUN MAR 30 2014
HIGH IMPACT WEATHER POTENTIAL: NONE.
PATTERN SUMMARY: AN EARLY MORNING LOOK AT THE PATTERN ACROSS THE
CONUS REVEALS AN ACTIVE SETUP...WITH LOW PRESSURE SYSTEMS ALONG BOTH
COASTS...AND A NARROW RIDGE OF HIGH PRESSURE IN BETWEEN THESE
SYSTEMS... ARCHING FROM QUEBEC...THROUGH THE GREAT LAKES AND DOWN
THE MISSISSIPPI VALLEY. THIS RIDGE AXIS CURRENTLY LIES JUST WEST OF
THE FORECAST AREA...WITH A RIBBON OF CLEARING ALLOWING LOW
TEMPERATURES TO FALL RAPIDLY AS BOUNDARY LAYER WINDS DECOUPLE.
LOOKING FORWARD THROUGH THE SHORT TERM FORECASTS REQUIRES US TO LOOK
UPSTREAM...AND...SOMEWHAT DIFFERENTLY THAN WE HAVE SEEN OF
LATE...MUCH OF WHAT IS UPSTREAM IS DOMINATED BY PACIFIC...MARITIME
POLAR AIR...WITH ANY ARCTIC AIR NOW BOTTLED UP NORTH OF THE REGION.
THIS PACIFIC FLOW WILL RESULT IN LEE-SIDE CYCLOGENESIS EAST OF THE
ROCKIES DURING THE DAY TODAY...WITH THIS LOW PRESSURE DEEPENING AND
BEGINNING TO DEPART TO THE NORTH AND EAST BY THE END OF THIS PERIOD
AROUND DAYBREAK MONDAY. THE DOWNSTREAM LONGWAVE TROUGH IS MUCH
SLOWER MOVING...AND THE DEVELOPING SQUEEZE PLAY IN BETWEEN THESE
FEATURES WILL FORCE HEIGHTS TO BUILD OVER THE GREAT LAKES WITH QUIET
AND MODERATING CONDITIONS EXPECTED FOR NORTHERN MICHIGAN. CERTAINLY
A WELCOME REPRIEVE FROM AN EXCEPTIONALLY COLD MONTH OF MARCH.
THROUGH DAYBREAK: TEMPERATURES WILL CONTINUE TO TUMBLE THROUGH THE
TEENS GIVEN CLEAR SKIES AND CALM-LIGHT WINDS. ALSO CAN/T RULE OUT
SOME PATCHY GROUND FOG GIVEN IMPRESSIVE OVERNIGHT COOLDOWN.
TODAY: RIDGE AXIS WILL BE PRETTY MUCH OVERHEAD TO START THE
DAY...GRADUALLY SHIFTING EAST TO A POSITION OVER LAKE HURON
TOWARDS EVENING. THERE/S A RELATIVE LACK OF MOISTURE THROUGH THE
COLUMN TO START THE DAY WITH PWATS SUB 0.25" /A LITTLE BELOW
SEASONAL NORMS FOR LATE MARCH/ WITH VALUES INCREASING DURING THE DAY
AS A CHUNK OF PACIFIC MOISTURE /SEEN NOW AS A PLUME OF DEEP MOISTURE
ACROSS THE NORTHWESTERN QUARTER OF THE COUNTRY/ RIDES EAST. WHILE
THIS COULD MANIFEST ITSELF AS SOME HIGH CLOUDS FOR THE NORTHERN HALF
OF THE CWA /ESP FOR THE SECOND HALF OF THE DAY/...THE LACK OF LLEVEL
MOISTENING BENEATH BUILDING MID LEVEL HEIGHTS SUGGESTS NO REAL
POTENTIAL FOR CU DEVELOPMENT. THUS...EXPECT ABUNDANT SUNSHINE FOR
THE AREA WITH NO SENSIBLE WEATHER CONCERNS.
TEMPERATURES /CONFIDENCE: HIGH/:
TRAJECTORY ANALYSIS PLACES THIS AFTERNOON/S AIRMASS OVER SOUTHERN
MINNESOTA 24 HOURS PREVIOUS WITH T9S SURGING TO 0-3C BY LATE
AFTERNOON UNDER STRONG WARM ADVECTION. WITH BUILDING HEIGHTS AND
NEARBY RIDGE AXIS...MIXING ISN/T GOING TO BE TOO STRONG. LOOKING
BACK TO MINNESOTA...AREAS THAT WERE UNABLE TO MIX DEEPLY REACHED THE
LOWER 40S...WITH UPPER 40S FURTHER WEST WHERE MECHANICAL MIXING
COMBINED WITH WARMER TEMPS ALOFT TO BOOST SURFACE TEMPS. EXPECT
THAT WE/LL BE CLOSER TO THE FORMER TODAY...AND EXPECT HIGHS IN THE
40-45 DEGREE RANGE. AMAZINGLY...THAT WILL PUT US JUST ABOUT WHERE
WE SHOULD BE FOR THE END OF MARCH.
AS MENTIONED BY THE PREVIOUS DAYSHIFT...LIGHT FLOW REGIME AND
SOMEWHAT WARMER TEMPERATURES SHOULD ALLOW FOR SOME LAKE BREEZE
DEVELOPMENT...KEEPING HIGHS LOCALLY COOLER ALONG THE LAKE HURON
COAST.
TONIGHT: RIDGE CONTINUES TO PUSH EAST OF THE GREAT LAKES
REGION...WITH NORTHERN STREAM COLD FRONT STALLING NEAR LAKE SUPERIOR
AS LOW PRESSURE ALONG THE EAST SLOPES OF THE ROCKIES BEGINS TO
DEPART AND HEAD NORTHEAST. MOISTURE CONTINUES TO SLOWLY
INCREASE...BUT PRIMARILY AT UPPER LEVELS WITH TOP-DOWN SATURATION
LIKELY ONLY YIELDING AN INCREASE IN UPPER LEVEL CLOUDS THROUGH THE
OVERNIGHT. GRADIENT STRENGTHENS THROUGH THE NIGHT...WITH MOST
LOCATIONS RE-COUPLING DURING THE OVERNIGHT. SEE NO REPEAT OF ANY
FOG GIVEN BETTER LLEVEL MIXING AND CONTINUED DRY LLEVEL CONDITIONS.
TEMPERATURES /CONFIDENCE: MODERATE-HIGH/:
TEMPERATURES WILL BE A LITTLE COMPLEX WITH EVENING MCLEAR SKIES AND
DECOUPLING LIKELY TO GIVE WAY TO INCREASED MIXING AS THE NIGHT GOES
ON. THIS WILL YIELD LOWS COLDEST OVER NORTHEAST LOWER WITH LOWS
LIKELY TO DIP TO AROUND 20 /AND PERHAPS A TAD BELOW THIS/...WITH
TEMPS OVER NORTHWEST LOWER STRUGGLING TO FALL MUCH BELOW THE
FREEZING MARK.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 309 AM EDT SUN MAR 30 2014
...REAL SPRING "WARMTH" GIVES WAY TO BELOW NORMAL TEMPERATURES (GO
FIGURE)...
HIGH IMPACT WEATHER POTENTIAL: WATCHING WINTRY PRECIP THREAT LATER
IN THE WEEK.
OVERVIEW: PATTERN REMAINS AN AGITATED ONE...WITH EXTENDED AMPED
PACIFIC REGIME OVER THE CONUS TUCKED NICELY ON SOUTH SIDE OF WELL
DEVELOPED NORTH CANADA COLD CORE GYRE. PACIFIC PATTERN CONTINUES TO
WIN OUT OVER NORTHERN MICHIGAN...WITH STEADY RETREAT OF OVERHEAD
COLD AIRMASS AS AGGRESSIVE UPSTREAM WARMING BEGINS. 00Z RAOB/HIGH
RES RAP GUIDANCE CONFIRMS SUCH...SHOWING H8 TEMPERATURES SPIKING
INTO THE TEENS (THAT`S ABOVE ZERO FOLKS!) ACROSS THE HIGH
PLAINS...WITH ABOVE ZERO H8 AIR ALREADY ADVANCING TO THE MISSISSIPPI
RIVER. EXPECTED RATHER SUBSTANTIAL UPPER MISSISSIPPI VALLEY LOW
PRESSURE DEVELOPMENT EARLY THIS WORK WEEK WILL ONLY HELP THE
NORTHERN LAKES WARMING CAUSE...WITH MUCH OF THE AREA TO FALL
SQUARELY IN THE WARM SECTOR OF THIS SYSTEM AS IT TRACKS TO OUR
NORTHWEST. UNFORTUNATELY...COOL AIR WILL BE FORCED SOUTH ON ITS
BACKSIDE...ONCE AGAIN DROPPING TEMPERATURES TO BELOW NORMAL LEVELS
AS WE HEAD THROUGH THE MID AND AND PORTIONS OF NEXT WEEK. PACIFIC
WAVE TRAIN REMAINS...AT LEAST SETTING UP SOME POTENTIAL FOR BOUTS OF
MORE WINTRY WEATHER HEADING INTO THURSDAY AND FRIDAY. OH...THE
JOY!
PRIMARY FORECAST CONCERNS/CHALLENGES: PLENTY! TEMPERATURE TRENDS
THROUGHOUT...PRECIP TIMING/AND EVENTUAL TYPE...HEADING THROUGH NEXT
WORK WEEK.
DETAILS: JUST HOW WARM TO GO ON MONDAY? ABOUT TEXTBOOK END OF
MARCH/BEGINNING OF APRIL SPRING STORM WILL BE UNDERGOING FULL
DEVELOPMENT ACROSS THE CENTRAL PLAINS EARLY MONDAY...EXPECTED TO
PASS SOMEWHERE VICINITY CENTRAL/WESTERN UPPER MICHIGAN TUESDAY.
STRONG DOWNSTREAM OFF THE DECK WAA EXPECTED...WITH NOW MULTI-DAY
PROGS SUPPORTING H8 READINGS SPIKING TO NEAR 10C BY LATER MONDAY
OVER NORTHERN MICHIGAN. WITH ELEVATED WARM FRONT ALREADY NORTH OF
THE AREA...AND CORE OF MID LEVEL DYNAMICS WELL OFF TO OUR
WEST...WOULD EXPECT PLENTY OF SUNSHINE TO FURTHER KICK THE WARMING
INTO OVERDRIVE. INCREASINGLY DEEP MIXED LAYER/FORCED MECHANICAL
MIXING PER INCREASING WINDS SHOULD ALLOW SURFACE TEMPERATURES TO
RESPOND ACCORDINGLY...AND REALLY LIKE INHERITED HIGHS WILL INTO THE
50S/NEAR 60 OVER NORTHERN LOWER MICHIGAN. SOUTHEAST LOW LEVEL FLOW
WILL KEEP NORTHEAST LOWER AND EASTERN UPPER MICHIGAN SEVERAL DEGREES
COOLER. MILD AIR CONTINUES INTO MONDAY NIGHT AS SOUTH FLOW
REMAINS...AND FEEL SOME AREAS MAY FAIL TO FALL OUT OF THE 40S. DRY
WEATHER GIVES WAY TO INCREASING SHOWER CHANCES MONDAY NIGHT AS
OCCLUDED FRONT INTERACTS WITH NARROW BAND OF ENHANCED DEEP LAYER
MOISTURE. STRONGEST AND DEEPEST DYNAMICS REMAIN TO OUR
NORTHWEST...WHERE HEAVIEST AND STEADIEST PRECIPITATION SHALL RESIDE.
BACK TO 2014 SPRING NORMALCY QUICKLY ON TUESDAY AS SURGE OF COLDER
AIR FOLLOWS PASSAGE OF OCCLUDED FRONT. MORNING HIGH TEMPERATURES IN
THE 30S AND 40S WILL SLOWLY FALL THROUGH THE AFTERNOON ON GUSTY
SOUTHWEST TO WEST WINDS. LIGHT RAIN/SNOW SHOWERS TRANSITION TO
MAINLY SNOW AS COLD AIR DEEPENS AND SYSTEM BACKSIDE MOISTURE
REMAINS. JUST MINIMAL...IF ANY...ACCUMULATION IS EXPECTED.
UNCERTAINTY THE NAME OF THE GAME HEADING INTO THE MID AND END
PORTIONS OF THE WEEK. QUESTIONS ARE MANY CONCERNING NEXT WAVE
EXPECTED TO EJECT OUT OF THE INTERMOUNTAIN WEST. INTERACTION BETWEEN
SOUTHERN CANADA HIGH/ASSOCIATED DRY AIR FEED AND WHAT SHOULD BE
RATHER VIGOROUS MID LEVEL WAVE LEADING TO RATHER SIGNIFICANT
DISCREPANCIES AMONGST MID RANGE GUIDANCE. ECMWF REMAINS MOST
ROCK-STEADY...SUGGESTING A MORE AMPED AND FURTHER NORTH SOLUTION
WITH LOW PRESSURE MOVING DIRECTLY ACROSS THE GREAT LAKES TO END THE
WORK WEEK. OTHER GUIDANCE STARTING TO FALL IN LINE WITH THIS MORE
NORTH/AMPED SOLUTION...ALTHOUGH HONESTLY...THIS DOES LITTLE TO
INCREASE CONFIDENCE AS A MORE SOUTH DISPLACED SYSTEM IS FULLY
PLAUSIBLE GIVEN EXPECTED SET-UP AND POTENTIAL FOR A STRONGER
CANADIAN HIGH. TEMPERATURE PROFILE REMAINS MARGINALLY SUPPORTIVE OF
A MIXED PRECIP EVENT IF FURTHER NORTH SOLUTIONS VERIFY. SET-UP ALSO
HAS SOME INTRIGUING FREEZING RAIN POSSIBILITIES...WITH POTENTIAL FOR
MAINTENANCE OF DRY AND COLD EAST FLOW TO MAINTAIN SUB-FREEZING
SURFACE TEMPERATURES...ALL THE WHILE ELEVATED WARM NOSE DEEPENS. OF
COURSE...MUCH TOO FAR OUT TO SHOW SUCH SPECIFICS...ESPECIALLY
CONSIDERING UNCERTAINTY IF SYSTEM WILL EVEN DIRECTLY AFFECT OUR
AREA. LITTLE CHOICE BUT TO RUN WITH A GENERIC RAIN/SNOW CHANCE
WORDING FOR NOW...WITH PLENTY OF TIME TO FINE-TUNE DETAILS IN
COMING DAYS. WHILE EXCEPTIONALLY COLD AIR NOW LOOKS LIKE A THING OF
THE PAST...OVERALL TRENDS FAVOR BELOW NORMAL TEMPERATURES WEDNESDAY
THROUGH NEXT WEEKEND...WITH HIGHS MOSTLY IN THE 30S AND LOWER
40S/OVERNIGHT LOWS IN THE 20S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 635 AM EDT SUN MAR 30 2014
UNRESTRICTED CONDITIONS EXPECTED AT ALL TAF SITES THROUGH THE
DURATION. ONLY SCT/BKN HIGH LEVEL CLOUDS. LIGHT SOUTH/SOUTHEAST
SURFACE WINDS EXPECTED TODAY ACROSS WESTERN TAF SITES...WITH A LAKE
INDUCED MORE EASTERLY COMPONENT AT KAPN. LIGHT/CALM WINDS
OVERNIGHT. LOW LEVEL JET INTENSIFIES TONIGHT...PRODUCING LLWS AT
ALL SITES EXCLUDING KAPN.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
SYNOPSIS...MSB
SHORT TERM...ARNOTT
LONG TERM...MSB
AVIATION...MSB
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
622 AM CDT SUN MAR 30 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 359 AM CDT SUN MAR 30 2014
ANOTHER WARM DRY SURGE OF AIR MOVES OFF THE CNTL ROCKIES TODAY. THE
TEMPERATURE FORECAST FOLLOWS THE UPPER MIDDLE OF THE 13 MODEL SUPER
ENSEMBLE FOR HIGHS IN THE 70S TO NEAR 80. A STATIONARY FRONT IS
EXPECTED TO DEVELOP ALONG THE SD BORDER CAUSING WINDS TO BACK ACROSS
THE NORTH KEEPING HIGHS NEAR 70. WE ALSO SEE A FAIRLY SOLID CIRRUS
SHIELD DEVELOPING OFF THE LARAMIE AND FRONT RANGE LIMITING HEATING
SOMEWHAT. SOUTH WINDS INCREASE TO 10 TO 20 MPH WITH GUSTS TO 25 MPH
ACROSS MOST OF THE FCST AREA.
FOR TONIGHT...SFC LOW PRESSURE WILL TRACK THROUGH THE CENTER OF THE
FCST AREA AND WINDS BECOME NORTHWEST BEHIND THE SFC LOW ACROSS WRN
NEB. ISOLATED THUNDERSTORMS ARE POSSIBLE THIS EVENING AND OVERNIGHT
IN RESPONSE TO A LOW LEVEL JET AND COOLING/FALLING HEIGHTS ALOFT.
THE NEW MODEL CONSENSUS BRINGS A SHARP 500 MB TROF INTO ERN WY AT
06Z WHICH CLOSES OFF ACROSS NW NEB BY 12Z. THERE ARE SIGNS OF THE
HEIGHTS BACKING IN ALOFT ACROSS WRN SD AT THIS TIME WHICH IS
TROUBLING SINCE THE LATEST ENSEMBLE SOLN IS TAKING THE UPPER LEVEL
ENERGY ACROSS THE TETONS AND BIG HORN RANGES BUT THEN IT DROPPING
SOUTH OF THE BLACK HILLS. THIS MORE SRN TRACK RAISES THE POP ACROSS
NWRN NEB BETWEEN 06Z AND 12Z. THE NAM AND GEM REGIONAL THEN BRING
THE RAIN SNOW LINE INTO NRN SHERIDAN COUNTY BETWEEN 09Z AND 12Z.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 359 AM CDT SUN MAR 30 2014
ATTENTION IN THE EXTENDED PERIODS CENTER ON PRECIPITATION
CHANCES...MAINLY THE POTENTIAL OF TWO SIGNIFICANT LATE WINTER TYPE
STORMS THAT MAY BRING ACCUMULATING SNOW TO PORTIONS OF THE CWA.
THE FIRST SYSTEM WILL BE ONGOING ACROSS OUR NORTHERN ZONES BY 12Z
MONDAY. LOW PRESSURE AND ASSOCIATED PV ANOMALY WILL CROSS FROM THE
CENTRAL ROCKIES NORTHEAST OUT ONTO PLAINS...DRAGGING MODIFIED
ARCTIC AIR SOUTH FROM CANADA ACROSS THE NORTHERN/CENTRAL PLAINS.
MEDIUM RANGE MODELS HAVE GENERALLY COME INTO FAIR AGREEMENT WITH
THE TRACK OF THE SURFACE CYCLONE...BUT INTENSITY/TIMING
DIFFERENCES STILL EXIST. ATTM GENERALLY FAVOR THE GEM SOLUTION IN
WHICH THE TRACK FAVORS STRONG FRONTOGENETIC FORCING MAINLY NORTH
OF THE CWA. THAT BEING SAID...THERE/S STILL STRONG AGREEMENT THAT
SNOW WILL WRAP AROUND THE LOW BACK ACROSS NORTHERN PORTIONS OF THE
CWA. ATTM SNOW ACCUMULATIONS LOOK FAVORABLE FOR NORTHWESTERN
NEBRASKA EARLY MONDAY...THEN TRANSITION EAST THROUGH THE DAY. THE
PTYPE FORECAST IS STILL PROBLEMATIC. THE GEM SOLUTION IS WARMER
WITHIN THE WARM SECTOR AS THE MODEL LIFTS THE LOW FURTHER NORTH
THAN EAST...CHANGEOVER TO ALL SNOW MAY NOT OCCUR FOR OUR FAR
EASTERN ZONES UNTIL MID-LATE AFTERNOON. WHERE THE CHANGE OVER DOES
OCCUR EARLY...IMPACTS TO TRAVEL WOULD BE EXPECTED...ESPECIALLY
GIVEN WIND GUSTS IN EXCESS 45 MPH. ATTM ALONG AND NORTH OF HIGHWAY
20 IN CHERRY AND SHERIDAN COUNTIES IS WHERE THE GREATEST
CONFIDENCE IN SEEING THE EARLY CHANGEOVER AND ACCUMULATING SNOW.
FOR THIS...WILL ISSUE A WINTER WEATHER ADVISORY WITH THIS FORECAST
PACKAGE FOR THE TWO COUNTIES LISTED AS IMPACTS TO
KVTN...RANCHING...HIGHWAY 20 AND THE POPULOUS CENTERED ALONG THE
HIGHWAY ARE ANTICIPATED TO BE SIGNIFICANT. NOTE...IT COULD VERY
WELL BE THAT SOUTHERN PORTIONS OF THESE TWO COUNTIES NOT SEE MUCH
IF ANY ACCUMULATING SNOW WITH THIS SYSTEM WHILE THE FAR NORTH
EXPERIENCES NEAR BLIZZARD CONDITIONS AND UP TO 4 INCHES OF SNOW. A
HIGH END WIND ADVISORY IS ANTICIPATED MONDAY AS WELL ACROSS THE
ENTIRE CWA. A STACKED PRESSURE GRADIENT WITH PRESSURE RISES ON THE
ORDER OF UP TO 3 MB PER HOUR WILL LEAD TO NEAR HIGH WIND WARNING
GUST CRITERIA. WILL LET THE DAY SHIFT FINE TUNE THE SPECIFICS.
LASTLY...NEGATIVE LI/S ACROSS NORTH CENTRAL/NORTHERN NEBRASKA
EARLY MONDAY WITH WEAK INSTABILITY ALOFT MAY YIELD A FEW EMBEDDED
CONVECTIVE SHOWERS...WHETHER SNOW OR RAIN. NO MENTION OF THUNDER
WAS INCLUDED BEYOND 12Z MONDAY...BUT MAY NEED TO BE LOOKED AT
FURTHER.
LOW AMPLITUDE TRANSITORY RIDGING BUILDS ATOP THE PLAINS ON TUESDAY
WITH A RETURN TO AN ACTIVE PATTERN BY MIDWEEK. SOUTHWESTERLY FLOW IN
THE UPPER LEVELS WILL PREVAIL AS THE NEXT LONGWAVE TROUGH OF
INTEREST STARTS TO BUILD ACROSS THE DESERT SOUTHWEST WEDNESDAY.
SLIGHT OPPORTUNITIES FOR QPF ALSO ARRIVE ON WEDNESDAY WITH THE
APPROACH OF FAVORABLE UPPER LEVEL JET SUPPORT AND A SW DISTURBANCE.
HOWEVER BETTER CHANCES ARRIVE LATE IN THE WEEK AS THE TROUGH EJECTS
NORTHEAST FROM THE 4 CORNERS ONTO THE CENTRAL PLAINS. THERE REMAINS
LARGE DISCREPANCIES ON HOW THE MODELS HANDLE THIS SYSTEM...WITH THE
ECMWF NOW TAKING ON A NEGATIVE TILT AND A FAVORABLE TRACK OF THE H5
LOW FOR SNOW ACCUMULATION...POSSIBLY SIGNIFICANT ACROSS THE WEST CENTRAL
SANDHILLS. THE GFS REMAINS OPEN AND PROGRESSIVE WITH FAR LESS
IMPACTS. DUE TO THE MYRIAD OF WEATHER CURRENTLY GOING ON RIGHT
NOW...FELT IT WAS BEST TO NOT VARY FROM A GENERAL MODEL BLEND WITH
THIS LATE WEEK SYSTEM.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 622 AM CDT SUN MAR 30 2014
VFR IS EXPECTED ALL AREAS TODAY THROUGH 06Z TONIGHT. ISOLATED
THUNDERSTORMS MAY DEVELOP IN THE WEST THIS EVENING WHICH WOULD
DEVELOP EASTWARD. THEREAFTER...AN APPROACHING UPPER LEVEL
TROF/DISTURBANCE...CURRENTLY MOVING THROUGH SRN CAL...WILL MOVE
INTO WRN NEB. MVFR IN RAIN CHANGING TO SNOW IS EXPECTED TO DEVELOP
ACROSS NORTHWEST NEB WHICH WILL SPREAD EAST...NORTH OF NEBRASKA
HIGHWAY 2. VFR IS EXPECTED SOUTH OF HIGHWAY 2.
&&
.FIRE WEATHER...
ISSUED AT 359 AM CDT SUN MAR 30 2014
RED FLAG CONDITIONS ARE EXPECTED ACROSS THE ERN PANHANDLE...CENTRAL
SANDHILLS...FRENCHMAN BASIN AND THE LOESS PLAINS. THE FORECAST IS A
LOW END RED FLAG WARNING AS THE RAP SHOWS WINDS AT 700MB WEAKENING
THIS AFTERNOON WHILE THE NAM ACTUALLY STRENGTHENS THEM. THE FORECAST
FOLLOWS A BLEND OF THE GUIDANCE FROM THE RAP13...HRRR...NAMDNG AND
AVN MOS MODELS FOR SOUTH WINDS OF 10 TO 20 MPH AND GUSTS TO 25 MPH.
DEWPOINTS SHOULD FALL INTO THE TEENS...BUT ABOUT 5 DEGREES F HIGHER
THAN SATURDAY.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 1 PM CDT /NOON MDT/ THIS AFTERNOON TO 9 PM
CDT /8 PM MDT/ THIS EVENING FOR NEZ204-206-210-219.
WINTER WEATHER ADVISORY FROM 4 AM CDT /3 AM MDT/ TO 7 PM CDT /6
PM MDT/ MONDAY FOR NEZ004-005-094.
&&
$$
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...CDC
FIRE WEATHER...CDC
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1044 AM EDT SUN MAR 30 2014
.SYNOPSIS...
A COMPLEX LOW PRESSURE SYSTEM WILL CONTINUE TO BRING MIXED
PRECIPITATION TO THE NORTH COUNTRY THIS MORNING...AND TAPER OFF
TO DRIZZLE AND FREEZING DRIZZLE THIS AFTERNOON. PORTIONS OF
CENTRAL AND SOUTHERN VERMONT WILL CONTINUE TO SEE LIGHT ICE
ACCUMULATIONS TONIGHT INTO MONDAY MORNING AS THE LOW TRACKS OFF
THE EASTERN SEABOARD...WITH DRIER CONDITIONS RETURNING TO THE
ENTIRE REGION BY MONDAY AFTERNOON.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1035 AM EDT SUNDAY...LOW PRESSURE ON DELAWARE COAST WILL
CONTINUE TO AFFECT NORTH COUNTRY WEATHER FOR THE REST OF TODAY AS
IT MOVES VERY SLOWLY EASTWARD...BECOMING CAPTURED BY CLOSED UPPER
LOW. MOST SIGNIFICANT AREA OF PRECIPITATION HAS LIFTED NORTH OF
FORECAST AREA...BUT LATEST RADAR CONTINUES TO SHOW BANDS OF
PRECIPITATION WHICH WILL LIKELY PERSIST THROUGH THE DAY. THIS
PRECIPITATION MOSTLY ON THE LIGHT SIDE...AND GENERALLY IN FORM OF
RAIN OR DRIZZLE IN VERMONT AND LIGHT SNOW OR MIXED PRECIPITATION
IN NEW YORK. ADDITIONAL ACCUMULATIONS OF SNOW/ICE TODAY SHOULD NOT
AMOUNT TO MUCH. NO CHANGES TO ADVISORIES/WARNINGS AT THIS
TIME...BUT WILL REASSESS AROUND MIDDAY. SITUATION MORE
COMPLICATED IN PARTS OF VERMONT WHERE SOME ADDITIONAL ICING
ANTICIPATED TONIGHT. TEMPS TODAY NOT CHANGING MUCH FROM CURRENT
READINGS. HAVE ADDED MENTION OF SOME FOG FOR MUCH OF THE AREA.
EARLIER DISCUSSIONS BELOW...
AS OF 716 AM EDT SUNDAY...QUICK UPDATE TO CANCEL ADVISORIES FOR
PORTIONS OF NORTHERN VERMONT AS BULK OF PRECIP SHIFTS NORTH OF
THE AREA AND PTYPE TRANSITIONS TO RAIN OR DRIZZLE.
PREVIOUS DISCUSSION...FORECAST PLAYING OUT FAIRLY WELL WITH A
MYRIAD OF PRECIPITATION TYPES EXPERIENCED ACROSS THE NORTH COUNTRY
OVERNIGHT ASSOCIATED WITH LOW PRESSURE MOVING EASTWARD THROUGH THE
MID-ATLANTIC STATES. ACROSS VERMONT...PRECIP STARTED OUT AS A MIX
OF SNOW...RAIN AND FREEZING RAIN BUT AS OF 5 AM SEEING MAINLY A
MIX OF RAIN AND SNOW. MEANWHILE...ACROSS NORTHERN NEW YORK SNOW
HAS BEEN THE PREDOMINANT PTYPE WITH SEVERAL INCHES OF SNOW
ACCUMULATIONS BEING REPORTED. MODEL OF CHOICE OVERNIGHT HAS BEEN
THE RAP WHICH CONTINUES TO HANDLE THE VERTICAL THERMAL STRUCTURE
VERY WELL SHOWING +0C LAYER AT 850MB SHIFTING NORTHWARD THROUGH VT
WHILE FROM THE SURFACE-925MB REMAINED NEARLY ISOTHERMAL. AS THE
BULK OF PRECIP SHIFTS NORTHWARD OUT OF THE REGION THIS
MORNING...WE`RE LEFT WITH SUPER-SATURATED LOW LEVELS AND ZERO ICE
IN THE FAVORED SNOW GROWTH REGION ALOFT ALONG WITH COOLING MID
LEVELS. THIS WILL SUPPORT A TRANSITION TO DRIZZLE AND/OR FREEZING
DRIZZLE ACROSS MOST OF THE AREA...THOUGH SOME LINGERING SNOW
SHOWERS WILL BE POSSIBLE ACROSS THE SAINT LAWRENCE VALLEY DUE TO
COLDER PROFILES. TEMPS WILL BASICALLY GO NOWHERE TODAY UNDER THICK
CLOUD COVER AND NORTH TO NORTHEASTERLY FLOW...HOLDING STEADY IN
THE LOW/MID 30S TO UPPER 20S AREA-WIDE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
AS OF 510 AM EDT SUNDAY...FOR TONIGHT INTO MONDAY...MODELS HAVE
COME INTO BETTER AGREEMENT IN REGARDS TO ANOTHER ROUND OF MIXED
PRECIPITATION ACROSS CENTRAL AND SOUTHERN VERMONT AS ADDITIONAL
SHORTWAVE ENERGY ROTATES AROUND THE SLOWLY DEPARTING UPPER LOW.
LOW LEVEL TEMPERATURES COOL ACROSS THE AREA OVERNIGHT WHILE TEMPS
AT MID-LEVELS REMAIN ABOVE FREEZING SETTING THE STAGE FOR AREAS OF
FREEZING DRIZZLE/RAIN THROUGH MONDAY MORNING. GREATEST CHANCES OF
ICE ACCUMULATION WILL BE OVER CENTRAL AND SOUTHEASTERN ZONES DUE
TO THE PROXIMITY WITH UPPER LOW....AND WINTER WX ADVISORIES HAVE
BEEN EXTENDED FOR A LIGHT GLAZE OF UP TO A TENTH OF AN INCH LIKELY.
LATE MONDAY INTO MONDAY NIGHT DRIER CONDITIONS RETURN TO THE
REGION AS DEEP LAYER RIDGING BUILDS EASTWARD FROM THE GREAT LAKES
INTO THE NORTHEAST. SKIES CLEAR FROM WEST TO EAST WITH ANOTHER
NIGHT OF BELOW NORMAL TEMPS EXPECTED IN THE TEENS TO 20S. SUNNY
CONDITIONS ARE EXPECTED FOR TUESDAY UNDER THE RIDGE WITH
TEMPERATURES REBOUNDING INTO THE 40S IN THE AFTERNOON.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 340 AM EDT SUNDAY...SEASONABLE EARLY SPRING TEMPERATURES
ALONG WITH PERIODIC CHANCES OF RAIN OR SNOW SHOWERS WILL BE THE
RULE DURING THE MIDDLE TO LATER PORTIONS OF NEXT WEEK. BEST SHOT
AT PCPN WILL OCCUR TUE NT/WED MORNING...THEN AGAIN BY NEXT
WEEKEND. THE MID-WEEK SYSTEM WILL BE RATHER WEAK AS NORTHERN
STREAM SHORTWAVE ENERGY PASSES TO OUR NORTH. THUS PCPN SHOULD BE
LIGHT AT BEST WITH MANY AREAS REMAINING DRY...ESP ACROSS OUR
SOUTHERN COUNTIES. THE SYSTEM FOR NEXT WEEKEND A LITTLE MORE
ROBUST SO A BETTER SHOT AREA WIDE FOR RAIN/SNOW SHOWERS. IN
BETWEEN (WED AFTERNOON THROUGH FRIDAY MORNING) GENERALLY HIGH
PRESSURE WITH CLEAR/PTLY CLOUDY SKIES AND DRY WEATHER EXPECTED.
HIGHS GENERALLY IN THE 40S THROUGH THE PERIOD WITH A SPOT 50 HERE
AND THERE POSSIBLE WED-FRI. OVERNIGHT LOWS GENERALLY FROM 25 TO 35
THOUGH MAINLY 20S WED NT/THU NT WITH AFOREMENTIONED HIGH PRESSURE
IN CONTROL AND BETTER SHOT AT PARTIALLY CLEAR SKIES.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
THROUGH 06Z MONDAY...WIDESPREAD MVFR/IFR ACROSS THE REGION AS
WIDESPREAD MIXED PCPN TAPERS TO DRIZZLE OR MUCH LIGHER/SCATTERED
RAINS/SNOWS. TERMINAL SPECIFIC DETAILS BELOW...
KBTV...MAINLY ON AND OFF LT RAIN OR DRIZZLE TAPERING OFF AFTER 21-00Z.
IFR/MVFR FLYING CONDS EXPECTED...WITH MAIN FOCUS OF IFR BEFORE 18Z.
WINDS NORTH/NORTHWESTERLY 7-15 AND OCCLY GUSTY TO 20 KTS THIS
AFTERNOON...ABATING TO 5 TO 10 KTS AFTER 00Z.
KPBG...PERIODS OF LIGHT SNOW OR MIXED LIGHT SNOW/SLEET WITH PATCHY
DRIZZLE EXPECTED THROUGH 21-00Z THEN TAPERING OFF. IFR/MVFR CIGS
THROUGH THE FORECAST PERIOD...WITH FOCUS OF IFR BEFORE 18Z. WINDS
NORTHERLY 10-20 KTS AND OCCNLY GUSTY TODAY...ABATING TO AROUND 10
KTS AFTER 00Z.
KMPV...MIX OF LIGHT RAIN/FZRA/FZDZ THROUGH THE FORECAST
PERIOD. IFR/MVFR CONDS EXPECTED THROUGH THE PERIOD. WINDS
NORTH/NORTHWESTERLY 6-12 KTS.
KRUT...PERIODS OF LIGHT RAIN OR DRIZZLE...THROUGH 00Z...WITH
PATCHES OF -FZDZ THEREAFTER. MIX OF VFR/MVFR FLYING CONDS
EXPECTED THROUGH THE PERIOD. WINDS EASTERLY 8 TO 15 KTS WITH GUSTS
TO 20 KTS...TRENDING NORTH TO NORTHEASTERLY FROM 18Z ONWARD.
KMSS...PERIODS LIGHT SNOW EXPECTED THROUGH 00Z...TAPERING TO SCT
SHSN THEREAFTER. IFR FLYING CONDS EXPECTED THROUGH
THIS MORNING...TRENDING MVFR AFTER 18Z. WINDS NORTHEASTERLY 15 TO
20 KTS WITH GUSTS TO 30 KTS EXPECTED...TRENDING NORTH AROUND 10
KTS AFTER 00Z. CONSIDERABLE BLSN LIKELY THROUGH 21Z.
KSLK...LIGHT/MODERATE SNOW EXPECTED WITH SOME MIX OF FZRA/PL
POSSIBLE...TAPERING TO SCT SHSN AFTER 18Z. WIDESPREAD
IFR...TRENDING MVFR AFTER 18Z. WINDS NORTHEASTERLY 6-12
KTS...OCCNL GUSTY TO 20KTS THIS AFTERNOON.
OUTLOOK 12Z MONDAY THROUGH THURSDAY...
12Z MONDAY TO 18Z MONDAY...TRENDING SLOWLY TO VFR FROM WEST TO EAST
AS LIGHT RAIN/SNOW/FZRA TAPERS OFF. BEST SHOT AT CONTINUED LIGHT
PMIXED CPN AND MVFR/IFR AT ERN TERMINALS OF KMPV/KRUT.
AGAIN...HIGHEST CONFIDENCE OF BETTER FLIGHT CONDS AT NRN NY
TERMINALS WITH CONTINUED UNCERTAINTY FURTHER EAST.
18Z MONDAY THROUGH 00Z WEDNESDAY...VFR WITH HIGH PRESSURE.
00Z WEDNESDAY THROUGH 00Z THURSDAY...VFR ALTHOUGH SOME BRIEF
PERIODS OF MVFR POSSIBLE IN SCATTERED RAIN/SNOW SHOWERS AS COLD
FRONT CROSSES REGION.
00Z THURSDAY ONWARD...VFR WITH HIGH PRESSURE.
&&
.HYDROLOGY...
AS OF 340 AM EDT SUNDAY...COMPLEX HYDRO SITUATION WILL DEVELOP
ACROSS OUR SOUTHERN WATERSHEDS TODAY WHERE A SOAKING RAINFALL ON
THE ORDER OF 1-1.75 INCHES WILL OCCUR. THIS IS A BLENDED MULTI-
MODEL SOLUTION WHICH APPEARS THE BEST COURSE FOR NOW GIVEN CURRENT
OBSERVATIONAL DATA. USING THIS QPF AND ALLOWING FOR 0.01-0.03
INCHES OF SWE MELT PER HOUR INDICATES MODEST TO LOCALLY SHARP
RISES IN EXCESS OF 4-5 FEET TODAY. WHILE WIDESPREAD OPEN WATER
FLOODING IS NOT EXPECTED GIVEN AT LEAST SOME ABSORPTION OF THE
RAIN INTO THE EXISTENT "NON-RIPE" SNOWPACK...THESE RISES MAY BE
MORE THAN SUFFICIENT TO PRODUCE ICE MOVEMENT AND/OR BREAKUP ACROSS
SCATTERED WATERSHEDS. THIS SEEMS LOGICAL SEEING ICE
MOVEMENT/BREAKUP TYPICALLY OCCURS WHEN RISES ARE ON THE ORDER OF
3X THE ICE THICKNESS. WHILE WE`LL HAVE TO WAIT AND SEE HOW THIS
COMPLEX SITUATION PANS OUT...CERTAINLY SOMETHING TO KEEP A CLOSE
EYE ON TODAY INTO TONIGHT.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...WINTER WEATHER ADVISORY UNTIL 11 AM EDT MONDAY FOR VTZ007-008-
010-012-018-019.
FLOOD WATCH THROUGH MONDAY MORNING FOR VTZ009>012-019.
WINTER WEATHER ADVISORY FROM 2 PM THIS AFTERNOON TO 11 AM EDT
MONDAY FOR VTZ011.
NY...WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR
NYZ026>029-035-087.
WINTER STORM WARNING UNTIL 2 PM EDT THIS AFTERNOON FOR NYZ030-
031-034.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...RJS/LAHIFF
SHORT TERM...LAHIFF
LONG TERM...JMG
AVIATION...JMG
HYDROLOGY...JMG
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
732 AM EDT SUN MAR 30 2014
.SYNOPSIS...
A COMPLEX LOW PRESSURE SYSTEM WILL CONTINUE TO BRING MIXED
PRECIPITATION TO THE NORTH COUNTRY THIS MORNING...AND TAPER OFF
TO DRIZZLE AND FREEZING DRIZZLE THIS AFTERNOON. PORTIONS OF
CENTRAL AND SOUTHERN VERMONT WILL CONTINUE TO SEE LIGHT ICE
ACCUMULATIONS TONIGHT INTO MONDAY MORNING AS THE LOW TRACKS OFF
THE EASTERN SEABOARD...WITH DRIER CONDITIONS RETURNING TO THE
ENTIRE REGION BY MONDAY AFTERNOON.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 716 AM EDT SUNDAY...QUICK UPDATE TO CANCEL ADVISORIES FOR
PORTIONS OF NORTHERN VERMONT AS BULK OF PRECIP SHIFTS NORTH OF THE
AREA AND PTYPE TRANSITIONS TO RAIN OR DRIZZLE.
PREVIOUS DISCUSSION...FORECAST PLAYING OUT FAIRLY WELL WITH A
MYRIAD OF PRECIPITATION TYPES EXPERIENCED ACROSS THE NORTH COUNTRY
OVERNIGHT ASSOCIATED WITH LOW PRESSURE MOVING EASTWARD THROUGH THE
MID-ATLANTIC STATES. ACROSS VERMONT...PRECIP STARTED OUT AS A MIX
OF SNOW...RAIN AND FREEZING RAIN BUT AS OF 5 AM SEEING MAINLY A
MIX OF RAIN AND SNOW. MEANWHILE...ACROSS NORTHERN NEW YORK SNOW
HAS BEEN THE PREDOMINANT PTYPE WITH SEVERAL INCHES OF SNOW
ACCUMULATIONS BEING REPORTED. MODEL OF CHOICE OVERNIGHT HAS BEEN
THE RAP WHICH CONTINUES TO HANDLE THE VERTICAL THERMAL STRUCTURE
VERY WELL SHOWING +0C LAYER AT 850MB SHIFTING NORTHWARD THROUGH VT
WHILE FROM THE SURFACE-925MB REMAINED NEARLY ISOTHERMAL. AS THE
BULK OF PRECIP SHIFTS NORTHWARD OUT OF THE REGION THIS
MORNING...WE`RE LEFT WITH SUPER-SATURATED LOW LEVELS AND ZERO ICE
IN THE FAVORED SNOW GROWTH REGION ALOFT ALONG WITH COOLING MID
LEVELS. THIS WILL SUPPORT A TRANSITION TO DRIZZLE AND/OR FREEZING
DRIZZLE ACROSS MOST OF THE AREA...THOUGH SOME LINGERING SNOW
SHOWERS WILL BE POSSIBLE ACROSS THE SAINT LAWRENCE VALLEY DUE TO
COLDER PROFILES. TEMPS WILL BASICALLY GO NOWHERE TODAY UNDER THICK
CLOUD COVER AND NORTH TO NORTHEASTERLY FLOW...HOLDING STEADY IN
THE LOW/MID 30S TO UPPER 20S AREA-WIDE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
AS OF 510 AM EDT SUNDAY...FOR TONIGHT INTO MONDAY...MODELS HAVE
COME INTO BETTER AGREEMENT IN REGARDS TO ANOTHER ROUND OF MIXED
PRECIPITATION ACROSS CENTRAL AND SOUTHERN VERMONT AS ADDITIONAL
SHORTWAVE ENERGY ROTATES AROUND THE SLOWLY DEPARTING UPPER LOW.
LOW LEVEL TEMPERATURES COOL ACROSS THE AREA OVERNIGHT WHILE TEMPS
AT MID-LEVELS REMAIN ABOVE FREEZING SETTING THE STAGE FOR AREAS OF
FREEZING DRIZZLE/RAIN THROUGH MONDAY MORNING. GREATEST CHANCES OF
ICE ACCUMULATION WILL BE OVER CENTRAL AND SOUTHEASTERN ZONES DUE
TO THE PROXIMITY WITH UPPER LOW....AND WINTER WX ADVISORIES HAVE
BEEN EXTENDED FOR A LIGHT GLAZE OF UP TO A TENTH OF AN INCH LIKELY.
LATE MONDAY INTO MONDAY NIGHT DRIER CONDITIONS RETURN TO THE
REGION AS DEEP LAYER RIDGING BUILDS EASTWARD FROM THE GREAT LAKES
INTO THE NORTHEAST. SKIES CLEAR FROM WEST TO EAST WITH ANOTHER
NIGHT OF BELOW NORMAL TEMPS EXPECTED IN THE TEENS TO 20S. SUNNY
CONDITIONS ARE EXPECTED FOR TUESDAY UNDER THE RIDGE WITH
TEMPERATURES REBOUNDING INTO THE 40S IN THE AFTERNOON.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 340 AM EDT SUNDAY...SEASONABLE EARLY SPRING TEMPERATURES
ALONG WITH PERIODIC CHANCES OF RAIN OR SNOW SHOWERS WILL BE THE
RULE DURING THE MIDDLE TO LATER PORTIONS OF NEXT WEEK. BEST SHOT
AT PCPN WILL OCCUR TUE NT/WED MORNING...THEN AGAIN BY NEXT
WEEKEND. THE MID-WEEK SYSTEM WILL BE RATHER WEAK AS NORTHERN
STREAM SHORTWAVE ENERGY PASSES TO OUR NORTH. THUS PCPN SHOULD BE
LIGHT AT BEST WITH MANY AREAS REMAINING DRY...ESP ACROSS OUR
SOUTHERN COUNTIES. THE SYSTEM FOR NEXT WEEKEND A LITTLE MORE
ROBUST SO A BETTER SHOT AREA WIDE FOR RAIN/SNOW SHOWERS. IN
BETWEEN (WED AFTERNOON THROUGH FRIDAY MORNING) GENERALLY HIGH
PRESSURE WITH CLEAR/PTLY CLOUDY SKIES AND DRY WEATHER EXPECTED.
HIGHS GENERALLY IN THE 40S THROUGH THE PERIOD WITH A SPOT 50 HERE
AND THERE POSSIBLE WED-FRI. OVERNIGHT LOWS GENERALLY FROM 25 TO 35
THOUGH MAINLY 20S WED NT/THU NT WITH AFOREMENTIONED HIGH PRESSURE
IN CONTROL AND BETTER SHOT AT PARTIALLY CLEAR SKIES.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
THROUGH 06Z MONDAY...WIDESPREAD MVFR/IFR ACROSS THE REGION AS
WIDESPREAD MIXED PCPN TAPERS TO DRIZZLE OR MUCH LIGHER/SCATTERED
RAINS/SNOWS. TERMINAL SPECIFIC DETAILS BELOW...
KBTV...MAINLY ON AND OFF LT RAIN OR DRIZZLE TAPERING OFF AFTER 21-00Z.
IFR/MVFR FLYING CONDS EXPECTED...WITH MAIN FOCUS OF IFR BEFORE 18Z.
WINDS NORTH/NORTHWESTERLY 7-15 AND OCCLY GUSTY TO 20 KTS THIS
AFTERNOON...ABATING TO 5 TO 10 KTS AFTER 00Z.
KPBG...PERIODS OF LIGHT SNOW OR MIXED LIGHT SNOW/SLEET WITH PATCHY
DRIZZLE EXPECTED THROUGH 21-00Z THEN TAPERING OFF. IFR/MVFR CIGS
THROUGH THE FORECAST PERIOD...WITH FOCUS OF IFR BEFORE 18Z. WINDS
NORTHERLY 10-20 KTS AND OCCNLY GUSTY TODAY...ABATING TO AROUND 10
KTS AFTER 00Z.
KMPV...MIX OF LIGHT RAIN/FZRA/FZDZ THROUGH THE FORECAST
PERIOD. IFR/MVFR CONDS EXPECTED THROUGH THE PERIOD. WINDS
NORTH/NORTHWESTERLY 6-12 KTS.
KRUT...PERIODS OF LIGHT RAIN OR DRIZZLE...THROUGH 00Z...WITH
PATCHES OF -FZDZ THEREAFTER. MIX OF VFR/MVFR FLYING CONDS
EXPECTED THROUGH THE PERIOD. WINDS EASTERLY 8 TO 15 KTS WITH GUSTS
TO 20 KTS...TRENDING NORTH TO NORTHEASTERLY FROM 18Z ONWARD.
KMSS...PERIODS LIGHT SNOW EXPECTED THROUGH 00Z...TAPERING TO SCT
SHSN THEREAFTER. IFR FLYING CONDS EXPECTED THROUGH
THIS MORNING...TRENDING MVFR AFTER 18Z. WINDS NORTHEASTERLY 15 TO
20 KTS WITH GUSTS TO 30 KTS EXPECTED...TRENDING NORTH AROUND 10
KTS AFTER 00Z. CONSIDERABLE BLSN LIKELY THROUGH 21Z.
KSLK...LIGHT/MODERATE SNOW EXPECTED WITH SOME MIX OF FZRA/PL
POSSIBLE...TAPERING TO SCT SHSN AFTER 18Z. WIDESPREAD
IFR...TRENDING MVFR AFTER 18Z. WINDS NORTHEASTERLY 6-12
KTS...OCCNL GUSTY TO 20KTS THIS AFTERNOON.
OUTLOOK 12Z MONDAY THROUGH THURSDAY...
12Z MONDAY TO 18Z MONDAY...TRENDING SLOWLY TO VFR FROM WEST TO EAST
AS LIGHT RAIN/SNOW/FZRA TAPERS OFF. BEST SHOT AT CONTINUED LIGHT
PMIXED CPN AND MVFR/IFR AT ERN TERMINALS OF KMPV/KRUT.
AGAIN...HIGHEST CONFIDENCE OF BETTER FLIGHT CONDS AT NRN NY
TERMINALS WITH CONTINUED UNCERTAINTY FURTHER EAST.
18Z MONDAY THROUGH 00Z WEDNESDAY...VFR WITH HIGH PRESSURE.
00Z WEDNESDAY THROUGH 00Z THURSDAY...VFR ALTHOUGH SOME BRIEF
PERIODS OF MVFR POSSIBLE IN SCATTERED RAIN/SNOW SHOWERS AS COLD
FRONT CROSSES REGION.
00Z THURSDAY ONWARD...VFR WITH HIGH PRESSURE.
&&
.HYDROLOGY...
AS OF 340 AM EDT SUNDAY...COMPLEX HYDRO SITUATION WILL DEVELOP
ACROSS OUR SOUTHERN WATERSHEDS TODAY WHERE A SOAKING RAINFALL ON
THE ORDER OF 1-1.75 INCHES WILL OCCUR. THIS IS A BLENDED MULTI-
MODEL SOLUTION WHICH APPEARS THE BEST COURSE FOR NOW GIVEN CURRENT
OBSERVATIONAL DATA. USING THIS QPF AND ALLOWING FOR 0.01-0.03
INCHES OF SWE MELT PER HOUR INDICATES MODEST TO LOCALLY SHARP
RISES IN EXCESS OF 4-5 FEET TODAY. WHILE WIDESPREAD OPEN WATER
FLOODING IS NOT EXPECTED GIVEN AT LEAST SOME ABSORPTION OF THE
RAIN INTO THE EXISTENT "NON-RIPE" SNOWPACK...THESE RISES MAY BE
MORE THAN SUFFICIENT TO PRODUCE ICE MOVEMENT AND/OR BREAKUP ACROSS
SCATTERED WATERSHEDS. THIS SEEMS LOGICAL SEEING ICE
MOVEMENT/BREAKUP TYPICALLY OCCURS WHEN RISES ARE ON THE ORDER OF
3X THE ICE THICKNESS. WHILE WE`LL HAVE TO WAIT AND SEE HOW THIS
COMPLEX SITUATION PANS OUT...CERTAINLY SOMETHING TO KEEP A CLOSE
EYE ON TODAY INTO TONIGHT.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...WINTER WEATHER ADVISORY UNTIL 11 AM EDT MONDAY FOR VTZ007-008-
010-012-018-019.
FLOOD WATCH THROUGH MONDAY MORNING FOR VTZ009>012-019.
WINTER WEATHER ADVISORY FROM 2 PM THIS AFTERNOON TO 11 AM EDT
MONDAY FOR VTZ011.
NY...WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR
NYZ026>029-035-087.
WINTER STORM WARNING UNTIL 2 PM EDT THIS AFTERNOON FOR NYZ030-
031-034.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...LAHIFF
SHORT TERM...LAHIFF
LONG TERM...JMG
AVIATION...JMG
HYDROLOGY...JMG
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
717 AM EDT SUN MAR 30 2014
.SYNOPSIS...
A COMPLEX LOW PRESSURE SYSTEM WILL CONTINUE TO BRING MIXED
PRECIPITATION TO THE NORTH COUNTRY THIS MORNING...AND TAPER OFF
TO DRIZZLE AND FREEZING DRIZZLE THIS AFTERNOON. PORTIONS OF
CENTRAL AND SOUTHERN VERMONT WILL CONTINUE TO SEE LIGHT ICE
ACCUMULATIONS TONIGHT INTO MONDAY MORNING AS THE LOW TRACKS OFF
THE EASTERN SEABOARD...WITH DRIER CONDITIONS RETURNING TO THE
ENTIRE REGION BY MONDAY AFTERNOON.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 716 AM EDT SUNDAY...QUICK UPDATE TO CANCEL ADVISORIES FOR
PORTIONS OF NORTHERN VERMONT AS BULK OF PRECIP SHIFTS NORTH OF THE
AREA AND PTYPE TRANSITIONS TO RAIN OR DRIZZLE.
PREVIOUS DISCUSSION...FORECAST PLAYING OUT FAIRLY WELL WITH A
MYRIAD OF PRECIPITATION TYPES EXPERIENCED ACROSS THE NORTH COUNTRY
OVERNIGHT ASSOCIATED WITH LOW PRESSURE MOVING EASTWARD THROUGH THE
MID-ATLANTIC STATES. ACROSS VERMONT...PRECIP STARTED OUT AS A MIX
OF SNOW...RAIN AND FREEZING RAIN BUT AS OF 5 AM SEEING MAINLY A
MIX OF RAIN AND SNOW. MEANWHILE...ACROSS NORTHERN NEW YORK SNOW
HAS BEEN THE PREDOMINANT PTYPE WITH SEVERAL INCHES OF SNOW
ACCUMULATIONS BEING REPORTED. MODEL OF CHOICE OVERNIGHT HAS BEEN
THE RAP WHICH CONTINUES TO HANDLE THE VERTICAL THERMAL STRUCTURE
VERY WELL SHOWING +0C LAYER AT 850MB SHIFTING NORTHWARD THROUGH VT
WHILE FROM THE SURFACE-925MB REMAINED NEARLY ISOTHERMAL. AS THE
BULK OF PRECIP SHIFTS NORTHWARD OUT OF THE REGION THIS
MORNING...WE`RE LEFT WITH SUPER-SATURATED LOW LEVELS AND ZERO ICE
IN THE FAVORED SNOW GROWTH REGION ALOFT ALONG WITH COOLING MID
LEVELS. THIS WILL SUPPORT A TRANSITION TO DRIZZLE AND/OR FREEZING
DRIZZLE ACROSS MOST OF THE AREA...THOUGH SOME LINGERING SNOW
SHOWERS WILL BE POSSIBLE ACROSS THE SAINT LAWRENCE VALLEY DUE TO
COLDER PROFILES. TEMPS WILL BASICALLY GO NOWHERE TODAY UNDER THICK
CLOUD COVER AND NORTH TO NORTHEASTERLY FLOW...HOLDING STEADY IN
THE LOW/MID 30S TO UPPER 20S AREA-WIDE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
AS OF 510 AM EDT SUNDAY...FOR TONIGHT INTO MONDAY...MODELS HAVE
COME INTO BETTER AGREEMENT IN REGARDS TO ANOTHER ROUND OF MIXED
PRECIPITATION ACROSS CENTRAL AND SOUTHERN VERMONT AS ADDITIONAL
SHORTWAVE ENERGY ROTATES AROUND THE SLOWLY DEPARTING UPPER LOW.
LOW LEVEL TEMPERATURES COOL ACROSS THE AREA OVERNIGHT WHILE TEMPS
AT MID-LEVELS REMAIN ABOVE FREEZING SETTING THE STAGE FOR AREAS OF
FREEZING DRIZZLE/RAIN THROUGH MONDAY MORNING. GREATEST CHANCES OF
ICE ACCUMULATION WILL BE OVER CENTRAL AND SOUTHEASTERN ZONES DUE
TO THE PROXIMITY WITH UPPER LOW....AND WINTER WX ADVISORIES HAVE
BEEN EXTENDED FOR A LIGHT GLAZE OF UP TO A TENTH OF AN INCH LIKELY.
LATE MONDAY INTO MONDAY NIGHT DRIER CONDITIONS RETURN TO THE
REGION AS DEEP LAYER RIDGING BUILDS EASTWARD FROM THE GREAT LAKES
INTO THE NORTHEAST. SKIES CLEAR FROM WEST TO EAST WITH ANOTHER
NIGHT OF BELOW NORMAL TEMPS EXPECTED IN THE TEENS TO 20S. SUNNY
CONDITIONS ARE EXPECTED FOR TUESDAY UNDER THE RIDGE WITH
TEMPERATURES REBOUNDING INTO THE 40S IN THE AFTERNOON.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 340 AM EDT SUNDAY...SEASONABLE EARLY SPRING TEMPERATURES
ALONG WITH PERIODIC CHANCES OF RAIN OR SNOW SHOWERS WILL BE THE
RULE DURING THE MIDDLE TO LATER PORTIONS OF NEXT WEEK. BEST SHOT
AT PCPN WILL OCCUR TUE NT/WED MORNING...THEN AGAIN BY NEXT
WEEKEND. THE MID-WEEK SYSTEM WILL BE RATHER WEAK AS NORTHERN
STREAM SHORTWAVE ENERGY PASSES TO OUR NORTH. THUS PCPN SHOULD BE
LIGHT AT BEST WITH MANY AREAS REMAINING DRY...ESP ACROSS OUR
SOUTHERN COUNTIES. THE SYSTEM FOR NEXT WEEKEND A LITTLE MORE
ROBUST SO A BETTER SHOT AREA WIDE FOR RAIN/SNOW SHOWERS. IN
BETWEEN (WED AFTERNOON THROUGH FRIDAY MORNING) GENERALLY HIGH
PRESSURE WITH CLEAR/PTLY CLOUDY SKIES AND DRY WEATHER EXPECTED.
HIGHS GENERALLY IN THE 40S THROUGH THE PERIOD WITH A SPOT 50 HERE
AND THERE POSSIBLE WED-FRI. OVERNIGHT LOWS GENERALLY FROM 25 TO 35
THOUGH MAINLY 20S WED NT/THU NT WITH AFOREMENTIONED HIGH PRESSURE
IN CONTROL AND BETTER SHOT AT PARTIALLY CLEAR SKIES.
&&
.AVIATION /11Z SUNDAY THROUGH THURSDAY/...
THROUGH 06Z MONDAY...WIDESPREAD MVFR/IFR ACROSS THE REGION IN
MODERATE TO HEAVY MIXED PCPN AND/OR RAIN AS LOW PRESSURE ALONG THE
NORTHERN MID-ATLANTIC COAST DRAWS COPIOUS MOISTURE NORTHWARD.
TERMINAL SPECIFIC DETAILS BELOW...
KBTV...MIX OF RAIN/FZRA THROUGH 12Z...THEN MAINLY LT RAIN TAPERING
TO SHOWERS AFTER 18Z. VFR/MVFR FLYING CONDS EXPECTED THROUGH THE
PERIOD W/BRIEF IFR POSSIBLE. WINDS NORTH/NORTHWESTERLY 7-15 KTS.
KMPV...MIX OF RAIN/FZRA THROUGH 12Z...THEN MAINLY LT RAIN TAPERING
TO SHOWERS AFTER 18Z. IFR/MVFR CONDS EXPECTED THROUGH THE PERIOD.
WINDS LGT AND VRB THROUGH 12Z...THEN NORTH/NORTHWESTERLY 6-12 KTS
THEREAFTER.
KRUT...PERIODS OF LIGHT RAIN...TAPERING TO SHOWERS BY 18Z. MIX OF
VFR/MVFR FLYING CONDS EXPECTED THROUGH THE PERIOD. WINDS EASTERLY
8 TO 15 KTS WITH GUSTS TO 20 KTS...TRENDING NORTH TO NORTHEASTERLY
AFTER 12Z.
KPBG...LIGHT TO MODERATE SNOW THROUGH 10-12Z...THEN MIXING WITH
SLEET. IFR LIKELY THROUGH 15Z...TRENDING MVFR THEREAFTER. SOME MIX
WITH RAIN ALSO POSSIBLE AFTER 16Z BEFORE PCPN TAPERS TO SHOWERS.
WINDS NORTHERLY 10-18 KTS AND TRENDING GUSTY TO 25 KTS THIS
AFTERNOON.
KMSS...LIGHT TO MODERATE SNOW EXPECTED THROUGH MUCH OF THE
PERIOD...TAPERING TO SCT SHSN AFTER 00Z MONDAY. IFR FLYING CONDS
EXPECTED THROUGH AFTERNOON...TRENDING MVFR AFTER 18Z. WINDS
NORTHEASTERLY 15 TO 22 KTS WITH GUSTS TO 30 KTS EXPECTED...ABATING
SLIGHTLY TOWARD EVENING. CONSIDERABLE BLSN LIKELY.
KSLK...LIGHT/MODERATE SNOW EXPECTED WITH SOME MIX OF FZRA/PL
POSSIBLE...TAPERING TO SCT SHSN/SHRA AFTER 18Z. WIDESPREAD
IFR...TRENDING MVFR AFTER 18Z. WINDS NORTHEASTERLY 6-12
KTS...OCCNL GUSTY TO 20KTS THIS AFTERNOON.
OUTLOOK 06Z MONDAY THROUGH THURSDAY...
06Z MONDAY TO 18Z MONDAY...TRENDING SLOWLY TO VFR FROM WEST TO
EAST AS LIGHT RAIN/SNOW TAPERS OFF. BEST SHOT AT CONTINUED LIGHT
PCPN AND MVFR/IFR AT ERN TERMINALS OF KMPV/KRUT. AGAIN...HIGHEST
CONFIDENCE OF BETTER FLIGHT CONDS AT NRN NY TERMINALS WITH
CONTINUED UNCERTAINTY FURTHER EAST.
18Z MONDAY THROUGH 00Z WEDNESDAY...VFR WITH HIGH PRESSURE.
00Z WEDNESDAY THROUGH 00Z THURSDAY...VFR ALTHOUGH SOME BRIEF
PERIODS OF MVFR POSSIBLE IN SCATTERED RAIN/SNOW SHOWERS AS COLD
FRONT CROSSES REGION.
00Z THURSDAY ONWARD...VFR W/MVFR PSBL LATE THURSDAY AS WARM FRONT
APPROACHES FROM SW...BRINGING PRECIP SOUTH TO NORTH.
&&
.HYDROLOGY...
AS OF 340 AM EDT SUNDAY...COMPLEX HYDRO SITUATION WILL DEVELOP
ACROSS OUR SOUTHERN WATERSHEDS TODAY WHERE A SOAKING RAINFALL ON
THE ORDER OF 1-1.75 INCHES WILL OCCUR. THIS IS A BLENDED MULTI-
MODEL SOLUTION WHICH APPEARS THE BEST COURSE FOR NOW GIVEN CURRENT
OBSERVATIONAL DATA. USING THIS QPF AND ALLOWING FOR 0.01-0.03
INCHES OF SWE MELT PER HOUR INDICATES MODEST TO LOCALLY SHARP
RISES IN EXCESS OF 4-5 FEET TODAY. WHILE WIDESPREAD OPEN WATER
FLOODING IS NOT EXPECTED GIVEN AT LEAST SOME ABSORPTION OF THE
RAIN INTO THE EXISTENT "NON-RIPE" SNOWPACK...THESE RISES MAY BE
MORE THAN SUFFICIENT TO PRODUCE ICE MOVEMENT AND/OR BREAKUP ACROSS
SCATTERED WATERSHEDS. THIS SEEMS LOGICAL SEEING ICE
MOVEMENT/BREAKUP TYPICALLY OCCURS WHEN RISES ARE ON THE ORDER OF
3X THE ICE THICKNESS. WHILE WE`LL HAVE TO WAIT AND SEE HOW THIS
COMPLEX SITUATION PANS OUT...CERTAINLY SOMETHING TO KEEP A CLOSE
EYE ON TODAY INTO TONIGHT.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...WINTER WEATHER ADVISORY UNTIL 11 AM EDT MONDAY FOR VTZ007-008-
010-012-018-019.
FLOOD WATCH THROUGH MONDAY MORNING FOR VTZ009>012-019.
WINTER WEATHER ADVISORY FROM 2 PM THIS AFTERNOON TO 11 AM EDT
MONDAY FOR VTZ011.
NY...WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR
NYZ026>029-035-087.
WINTER STORM WARNING UNTIL 2 PM EDT THIS AFTERNOON FOR NYZ030-
031-034.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...LAHIFF
SHORT TERM...LAHIFF
LONG TERM...JMG
AVIATION...BANACOS/JMG
HYDROLOGY...JMG
AREA FORECAST DISCUSSION
NWS RALEIGH NC
650 AM EDT SUN MAR 30 2014
.SYNOPSIS... A COLD FRONT WILL SWEEP EAST THROUGH CENTRAL NORTH
CAROLINA EARLY THIS MORNING... AND WILL BE FOLLOWED BY BRISK AND
GUSTY WINDS FROM THE NORTHWEST PULLING COOLER AIR INTO THE REGION.
HIGH PRESSURE WILL BUILD IN FROM THE WEST TONIGHT INTO EARLY NEXT
WEEK.
&&
.NEAR TERM /TODAY THROUGH TONIGHT/...
AS OF 300 AM SUNDAY...
UPDATE FROM 650 AM: LATEST RAP MODEL FORECAST SOUNDINGS INDICATES A
VERTICAL THERMAL STRUCTURE SUPPORTIVE OF A CHANCE OF A LITTLE WET
SNOW MIXED IN WITH THE LIGHT RAIN OVER THE TRIAD FOR THE NEXT FEW
HOURS. OUR WEATHER OBSERVER AT GSO AIRPORT JUST REPORTED A FEW
FLAKES MIXED IN WITH THE LIGHT SHOWERS THERE RECENTLY. WITH A FAIRLY
DRY SUBCLOUD LAYER... STILL EXPECT VERY LOW PRECIP AMOUNTS... BUT
THE WET BULB BRIEFLY DROPS CLOSE TO FREEZING AT THE SURFACE EARLY
THIS MORNING IN THE TRIAD REGION... WITH THE REMAINDER OF THE COLUMN
BELOW FREEZING. HAVE INCLUDED A MENTION OF A FEW SNOWFLAKES OVER THE
NEXT FEW HOURS IN THE NW CWA. -GIH
THE PRIMARY WEATHER CONCERN TODAY IS THE STRONG GUSTY NW WINDS AND
POTENTIALLY ADVERSE IMPACTS SUCH AS DOWNED BRANCHES AND WEAKLY
ROOTED TREES. CURRENTLY... SHORT BANDS OF SHOWERS PRODUCING LOCALLY
ENHANCED WINDS CONTINUE TO PIVOT AROUND THE MID LEVEL LOW OVER SW VA
THIS MORNING... MAINLY AFFECTING THE NRN CWA AS POCKETS OF VORTICITY
STREAK TO THE NNE ON THE SRN/ERN SIDE OF THE LOW. THIS LOW IS
EXPECTED TO TRACK EASTWARD ALONG THE NC/VA STATE LINE THROUGH
MIDDAY... SHIFTING NE OFF THE TIDEWATER/DELMARVA SHORE DURING THE
MID TO LATE AFTERNOON... AND IT`S EXPECTED TO BRING PATCHY SHOWERS
(MOVING MORE WEST-TO-EAST) THROUGH MID AFTERNOON ACROSS OUR NRN
CWA... WHERE FORECAST SOUNDINGS AND EXTRAPOLATION OF UPSTREAM
CONDITIONS SUPPORT A RATHER DEEP LAYER OF MOISTURE AT 850-700 MB.
THE COMPARATIVELY DRY AND WELL-MIXED SUBCLOUD LAYER HOWEVER WILL
GREATLY LIMIT QPF. REGARDING TODAY`S WIND... THE MSLP GRADIENT
BETWEEN THE DEEP SURFACE LOW ANALYZED OVER THE CHESAPEAKE BAY/SRN
DELMARVA AND THE INCOMING SURFACE HIGH FROM THE WEST TIGHTENS UP
THIS MORNING... AND STATISTICAL GUIDANCE AS WELL AS HIGH-RES MODEL
OUTPUT SUCH AS THE HRRR AND LOCAL WRF ALL SUPPORT SUSTAINED WINDS OF
15-25 MPH MAINLY OVER THE WRN AND SRN HALVES OF THE CENTRAL NC
FORECAST AREA... AND TRANSPORT OF MOMENTUM WITHIN THE GROWING MIXED
LAYER INDICATES GUSTS OF 30-36 KTS OVER THIS SAME AREA. WHILE THESE
SPEEDS MAY NOT QUITE REACH OUR WIND ADVISORY CRITERIA EVERYWHERE...
THE ANTICIPATED IMPACTS (A FEW DOWNED BRANCHES/TREES AND SPORADIC
POWER OUTAGES) WARRANT ISSUANCE OF A WIND ADVISORY... TO BE IN
EFFECT FOR AREAS WEST AND SOUTH OF THE TRIANGLE THROUGH MID EVENING
(WHEN WINDS ARE EXPECTED TO SUBSIDE). BELOW-NORMAL LOW LEVEL
THICKNESSES COMBINED WITH CONSIDERABLE CLOUDINESS PARTICULARLY OVER
THE NRN TWO-THIRDS OF THE CWA WILL HOLD TEMPS DOWN TODAY... AND
EXPECT HIGHS OF 53-62... AROUND 10-12 DEGREES BELOW NORMAL. THE
DEPARTURE OF THE SURFACE AND MID LEVEL LOWS TO OUR NE AFTER
NIGHTFALL AND STRONG SUBSIDENCE (100-120 M MID LEVEL HEIGHT RISES)
SHOULD FOSTER QUICK CLEARING FROM WSW TO ENE. WINDS WILL DECREASE
BUT SHOULD STILL HOLD UP ENOUGH TO KEEP THE LOW LEVELS STIRRED
OVERNIGHT... KEEPING TEMPS FROM FALLING DOWN TO THE FORECAST DEW
POINTS (WHICH SHOULD FALL TO THE MID 20S TO AROUND 30). AS SUCH...
EXPECT LOWS TO STAY ABOVE FREEZING TONIGHT. DESPITE LOWS IN THE MID
30S IN MANY AREAS... THE DRY AIR SHOULD LIMIT FROST DEVELOPMENT
TONIGHT... BUT WILL TAKE ANOTHER LOOK AT THIS LATER TODAY. LOWS
MAINLY 35-40. -GIH
&&
.SHORT TERM /MONDAY AND MONDAY NIGHT/...
AS OF 315 AM SUNDAY...
PLENTY OF SUNSHINE EXPECTED MONDAY... WITH CONTINUED DRY AIR
ADVECTION THROUGH THE COLUMN AND HIGH PRESSURE STARTING TO BUILD IN
AT THE SURFACE... AND MID LEVEL RIDGING APPROACHING FROM THE WEST. A
BREEZE OUT OF THE NW SHOULD PERSIST BUT NOT NEARLY AS STRONG AS WE
SHOULD SEE TODAY. LOW LEVEL THICKNESSES RECOVER NICELY TO NEAR-
NORMAL LEVELS MON MORNING AND RISE QUICKLY THROUGH THE DAY...
SUPPORTING HIGHS FROM THE UPPER 60S NE TO MID 70S SW... A BIT ABOVE
NORMAL FOR THIS TIME OF YEAR. EXPECT GOOD RADIATIONAL COOLING MON
NIGHT... ALTHOUGH THE INCREASING SURFACE DEW POINTS MON NIGHT WILL
OFFSET THE CALM TO VERY LIGHT WINDS TO KEEP TEMPS FROM FALLING TOO
MUCH. LOWS 38-42... JUST SLIGHTLY BELOW NORMAL. -GIH
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 255 AM SUNDAY...
A SUBTROPICAL RIDGE WILL DEVELOP OVER THE SOUTHEAST US BY TUESDAY
WITH A SURFACE HIGH OFF THE SOUTHEAST COAST. THIS WARM
PATTERN...WITH LOW LEVEL THICKNESSES CLIMBING ABOVE 1370M...WILL
SUPPORT HIGHS IN THE MID AND UPPER 70S EACH DAY...WITH LOWER 80S NOT
OUT OF THE QUESTION ACROSS THE SOUTH AND EAST WEDNESDAY AND
THURSDAY.
A SHORTWAVE LIFTING THROUGH THE GREAT LAKES REGION WILL SEND A
MOSTLY DRY COLD FRONT INTO THE MID-ATLANTIC STATES TUESDAY
AFTERNOON...BUT GIVEN THE STRENGTH OF THE RIDGE...EXPECT THIS FRONT
OR REMNANT TROUGH TO REMAIN NORTH OF THE AREA. A MORE VIGOROUS
SYSTEM IS FORECAST TO LIFT THROUGH THE MIDWEST STATES ON
FRIDAY...THOUGH THE GFS AND ECMWF DIFFER REGARDING THE STRENGTH OF
THE WAVE AND THE TIMING OF THE ASSOCIATED COLD FRONT. PREFER A
SOLUTION SLOWER THAN THE ECMWF ON FRIDAY...BUT NOT AS SLOW AS THE
GFS WHICH DOESNT BRING THE FRONT IN UNTIL SATURDAY. NEITHER
SOLUTION LOOKS TO DRAW A TON OF MOISTURE FROM THE GULF...SO WILL
KEEP POPS CAPPED AT SLIGHT CHANCE NOW BASED ON THE PATTERN AND MODEL
DIFFERENCES.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AS OF 650 AM SUNDAY...
THE BIGGEST AVIATION CONCERN TODAY IS THE STRONG SURFACE WINDS FROM
THE NW... INCREASING TO 15-20 KTS GUSTING TO 25-35 KTS... STRONGEST
AFTER 17Z THIS AFTERNOON AS OUR LOW LEVELS MIX MORE DEEPLY. THIS MAY
POSE A CROSSWIND THREAT FOR AIRCRAFT AT GSO/RDU/FAY/RWI. CURRENT
CIGS ARE MOSTLY VFR... ALTHOUGH PATCHY SHOWERS ACROSS THE AREA MAY
BRIEFLY REDUCE CIGS TO MVFR BRIEFLY THIS MORNING. OTHERWISE... WITH
EARLY-DAY HEATING AND RESIDUAL MOISTURE ALOFT... EXPECT TO SEE A
PERIOD OF HIGH-END MVFR CIGS (2000-3000 FT AGL) MAINLY AT RDU/RWI
BETWEEN 12Z AND 17Z THIS MORNING/MIDDAY. THESE CIGS SHOULD LIFT TO
VFR SOON AFTER 17Z. ELSEWHERE... ANY CIGS ARE LIKELY TO BE VFR...
AND VSBYS WILL BE VFR AREAWIDE THROUGH TONIGHT. WINDS WILL DECREASE
THIS EVENING (AFTER 01Z) TO 10-15 KTS WITH ONLY SPORADIC GUSTS TO 20
KTS FROM THE NW THROUGH THE END OF THE TAF VALID PERIOD.
LOOKING BEYOND 12Z MONDAY MORNING: HIGH CONFIDENCE IN VFR CONDITIONS
AT ALL SITES THROUGH THURSDAY... AS HIGH PRESSURE BUILDS OVER THE
REGION AND REMAINS OVER AND JUST OFF THE SOUTHEAST COAST THROUGH
MIDWEEK. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 10 PM EDT THIS EVENING FOR NCZ007-021>024-
038>040-073>077-083>086-088.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...HARTFIELD
LONG TERM...SMITH
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1053 AM EDT SUN MAR 30 2014
.SYNOPSIS...
AN UPPER LEVEL LOW WILL SHIFT OFF THE COAST THIS AFTERNOON. HIGH
PRESSURE WILL RETURN TO THE AREA LATE TONIGHT AND MONDAY. A FRONT
MOVES THROUGH BY TUESDAY NIGHT BUT LOOKS DRY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1030 AM EDT SUNDAY...
PERSISTENT BANDS OF HEAVY SNOW CONTINUE TO SPILL SOUTH FROM BATH
COUNTY EAST TO AMHERST WITH ELEVATION ALLOWING SNOW TO QUICKLY
ACCUMULATE TO BETTER THAN 6 INCHES IN STRIPS ALONG THE I-64 TO
I-81 CORRIDOR UP NORTH. LATEST RAP AND LOCAL MODEL SOLNS SUGGEST
ANOTHER HOUR OR SO OF ACCUMULATING SNOWFALL IN THESE AREAS BEFORE
THE DEFORMATION AREA FINALLY SHIFTS SE AND WEAKENS. THUS WILL
KEEP THE ADVISORY GOING ACROSS PARTS OF THE SOUTHERN SHENANDOAH
VALLEY WHILE INCLUDING LOCALLY HIGHER TOTALS GIVEN THE HUGE RANGE
ACROSS COUNTIES WITH LITTLE AT LOWER ELEVATIONS. ELSEWHERE SHOULD
BE WARM ENOUGH FOR MOSTLY RAIN FARTHER SOUTH WITH ONLY SOME SNOW
MIXED IN NORTH OF HIGHWAY 460 FOR A WHILE LONGER. PRECIP HAS
TAPERED WEST OF THE NEW RIVER VALLEY SO WILL BE REMOVING COUNTIES
FROM THE WINTER WX ADVISORY THERE WHILE KEEPING THE WARNINGS
GOING INTO SE WVA GIVEN SOME CONTININUING LIGHT SNOWFALL. LITTLE
CHANGE TO GOING WIND HEADLINES WITH THE STRONGEST SPEEDS
CONTINUING ALONG THE SOUTHERN BLUE RIDGE BUT LIKELY TO SHIFT NE AS
SOME BREAKS DEVELOP THIS AFTERNOON UNDER A SECONDARY LOW LEVEL JET
MAX THAT LOOKS TO PIVOT ACROSS BY MID AFTERNOON. BEEFED UP CLOUDS
LONGER PER LATEST VIS PICS WITH TEMPS REMAINING BELOW MOS SO
LOWERED A CAT OR SO ACROSS THE REGION FOR THE AFTERNOON.
AS OF 915 AM EDT SUNDAY...
QUICK UPDATE TO ADD THE HIGHER ELEVATIONS OF ROCKBRIDGE AND
AMHERST TO THE GOING WINTER WEATHER ADVISORY DUE TO HEAVIER SNOW
BANDS ON THE BACK EDGE OF THE DEFORMATION ZONE. EXPECT MOST
ACCUMULATION TO BE NEAR THE BLUE RIDGE PARKWAY WITH LESS THAN AN
INCH ELSEWHERE ACROSS THAT REGION. ALSO BUMPED UP AMOUNTS ACROSS
NORTHERN BATH WHERE HAVE ALREADY SEEN 2-3 INCHES. REMAINDER
UNCHANGED AS EXPECT LESS AND LESS ACCUMULATION WITH SOME SLOW
WARMING DURING THE MORNING HOURS. STRONGER WINDS ALONG THE BLUE
RIDGE MAY BE REALIZED OVER THE NEXT FEW HOURS BUT WILL NEED SOME
CLEARING TO ENHANCE MIXING WHICH MAY NOT HAPPEN IN TIME BUT WILL
CONTINUE THE WARNING FOR NOW.
PREVIOUS DISCUSSION AS OF 720 AM EDT SUNDAY...
RADAR CONTINUES TO SHOW DEFORMATION AXIS PIEDMONT WITH NW FLOW
RAIN AND SNOW SHOWERS OVER THE WEST. RADAR OVERSHOOTING THE SNOW
PAST I-77 AND IN NC MTNS. MODELS AGREE THAT DRYING TAKES PLACE
FROM SW TO NE THROUGH THE MORNING AND WILL SEE SNOW SHOWERS AND
RAIN OUT EAST START TO WANE LATE MORNING INTO MID AFTERNOON. STILL
LOOKS LIKE A GOOD 2-6 INCHES POSSIBLE OF SNOW IN THE HIGHER
ELEVATIONS...AND SOME POCKETS OF 1-3 INCHES IN NARROW CORRIDORS
FROM SE WV INTO THE NW NC MTNS AND NEW RIVER VALLEY.
WIND WILL KEEP THE SNOW MEASURING AN ISSUE...AND OVERALL WINDS
WILL BE GUSTY BUT STRONGEST WINDS WILL ARRIVE AS CLEARING TAKES
PLACE AND STILL LOOKING AFTERNOON FOR MOST. ALREADY HAVE HAD GUSTS
OVER 65 MPH AT BOONE...AND A TREE DOWN IN TODD NC.
NO CHANGES WERE MADE TO THE HEADLINES.
PREVIOUS DISCUSSION ISSUED EARLIER THIS MORNING...
OVERALL...MARCH IS TRYING TO GO OUT LIKE A LION...BUT IT WILL HAVE
TO SETTLE FOR THE DAY BEFORE THE END OF THE MONTH.
RADAR THIS MORNING SHOWS THE DEFORMATION ZONE PRECIP LIFTING NWD
ACROSS THE ALLEGHANY HIGHLANDS SOUTHEAST TOWARD SOUTHSIDE VA. THE
PRECIP OVER THE MOUNTAINS HAS CHANGED TO ALL SNOW...BUT SO FAR
LITTLE ACCUMULATION REPORTS...ALTHOUGH THINK MORE WILL BE COMING IN
AS WE HEAD TOWARD DAYLIGHT HOURS. NICE CYCLONIC FLOW SEEN IN THE
RADAR ECHOES AS WELL...WITH UPSLOPE WELL UNDER WAY OVER THE NC
MTNS...NWD INTO SE WV.
HAVE NOT MADE ANY ADDITIONAL CHANGES TO THE HEADLINES...BUT THE
WINDS WILL BE HIT AND MISS THIS MORNING THANKS TO THE CLOUD COVER.
AS WE HEAD THRU THE DAY...THE UPPER LOW WILL MOVE EAST OF THE
DELMARVA WITH STRONG NVA ARRIVING WHICH HELPS TO MIX OUT THE CLOUDS.
FORECAST MOS GUIDANCE AND BUFKIT SOUNDINGS STILL SUGGEST STRONG
WINDS ESPECIALLY THIS AFTERNOON. SOME AREAS WILL NOT REALLY GET TO
ADVISORY OR WARNING LEVELS BUT GIVEN WET GROUNDS...WIND SPEEDS JUST
BELOW WILL CAUSE SOME PROBLEMS. WHERE THE WARNING IS IN
PLACE...THINK 50 TO 60 MPH GUSTS ARE LIKELY AND FEEL THAT TREES ARE
GOING TO BE BLOWN DOWN. HOPEFULLY...NO DAMAGE TO HOMES OR BUSINESSES
WILL OCCUR. ADVISORY AREAS WILL BE MORE FORTUNATE BUT EXPECT SOME
TREE DOWN REPORTS AS WELL.
THE SNOW WILL ALSO TAPER OFF THIS AFTERNOON AS THE UPPER LOW MOVES
AWAY. STILL LOOKS LIKE ELEVATIONS ABOVE 3000 FT WILL GET AS MUCH AS
6 INCHES WHEN ALL IS SAID AND DONE...ESPECIALLY WRN GREENBRIER.
MOIST/WET GROUND WILL HAVE SOME IMPACT ON STICKING...BUT RATE SHOULD
BE HIGH ENOUGH TO GIVE THE HIGHER VALLEYS IN THE WEST A 1-2 INCH
COATING. THOUGH NO ADVISORY IS IN PLACE FOR SNOW ALONG THE BLUE
RIDGE...THINK LOCATIONS SUCH AS POOR MOUNTAIN...PEAKS OF OTTER AND
APPLE ORCHARD MOUNTAIN COULD SEE 1 TO 3 INCHES OF SNOW.
HIGHS TODAY WILL BE TRICKY GIVEN COLD AIR ADVECTION THIS
MORNING...THEN NEUTRAL ADVECTION THIS AFTERNOON...PLUS LATE MARCH
SUN AND DOWNSLOPE. WENT WITH MID 50S EAST OF THE BLUE RIDGE...TO 40S
WEST...WITH 30S IN THE HIGHEST ELEVATIONS FROM BEECH MTN NC...MOUNT
ROGERS VA AND THE WRN SLOPES OF GREENBRIER COUNTY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
AS OF 329 AM EDT SUNDAY...
THE CLOSED LOW THAT WILL TRACK OVER THE FORECAST AREA TODAY WILL
BECOME AN OCCLUDED LOW OFF THE DELMARVA COAST THIS EVENING. THE
ASSOCIATED PRECIPITATION WITH THIS SYSTEM SHOULD BE EAST OF THE
PIEDMONT BY SUNSET. MEANWHILE...HIGH PRESSURE WILL DRIFT EAST OVER
THE OHIO-TENN VALLEYS TONIGHT. THE PRESSURE GRADIENT BETWEEN THESE
TWO SYSTEMS WILL CONTINUE TO PRODUCE WINDY/GUSTY CONDITIONS INTO THE
EVENING. THE PRESSURE GRADIENT STARTS TO LOOSEN AFTER MIDNIGHT
ALLOWING WINDS TO WEAKEN ACROSS THE FOOTHILLS AND PIEDMONT. WINDY
CONDITIONS WILL REMAIN ACROSS THE MOUNTAINS...PARTICULARLY ALONG THE
BLUE RIDGE INTO THE EARLY MORNING HOURS MONDAY. OVERNIGHT MIXING
WILL KEEP RIDGE TOP TEMPERATURES MILDER THAN THE VALLEYS. MOUNTAIN
VALLEY TEMPERATURES WILL RANGE IN THE M/U20S WHILE RIDGES RANGE
BETWEEN 30F-35F. EVEN THOUGH THE WINDS RELAX IN THE EAST EARLY...NOT
AN IDEAL SITUATION FOR RADIATIONAL COOLING...THEREFORE KEPT
OVERNIGHT TEMPERATURES IN THE 30S.
WHAT A DIFFERENCE A DAY MAKES WITH MONDAYS HIGH TEMPERATURES IN THE
60S ACROSS THE WEST AND U60S-L70S IN THE EAST. RELATIVE HUMIDITIES
WILL DROP INTO THE 20S MONDAY AFTERNOON WHILE NORTHWEST WINDS PEAK
BETWEEN 10-15 MPH. WARMER TUESDAY WITH TEMPERATURES PUSHING 70F
ACROSS THE MOUNTAINS AND WIDESPREAD 70S EAST. HUMIDITY LEVELS
SLIGHTLY HIGHER AROUND 30 PERCENT TUESDAY WITH THE LOW LEVEL FLOW
COMING FROM THE SOUTHWEST. BOTH DAYS LOOK IDEAL FOR PRESCRIBE BURNS
WITH THE STRONGER TRANSPORT WINDS OCCURRING TUESDAY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 1145 AM EDT SATURDAY...
BROAD UPPER RIDGING TO REMAIN IN PLACE UNTIL NEAR THE END OF THE
PERIOD WITH SURFACE HIGH PRESSURE OFF THE SE COAST AND MEAN
TROUGHING ACROSS THE CENTRAL AND SW STATES. WILL SEE A WEAK SURFACE
FRONT PUSH SOUTH OF THE REGION WEDNESDAY AS A WAVE PASSES WELL TO
THE NORTH AND HEIGHTS DIP A BIT. HOWEVER THIS BOUNDARY INITIALLY DRY
WITH ONLY WEAK HIGH PRESSURE TO THE NW WHICH SHOULD DO LITTLE TO
DETER VERY WARM TEMPS FOR MIDWEEK. FRONT LOOKS TO LIFT BACK NORTH
THROUGH THE REGION THURSDAY AS STRONGER LOW PRESSURE PIVOTS TOWARD
THE UPPER MIDWEST. BAND OF DEEPER MOISTURE/LIFT MAY TEND TO SPILL
DOWN THE BAROCLINIC ZONE FROM THE WEST SO BUMPED UP POPS STARTING
THURSDAY MORNING...CONTINUING INTO THURSDAY EVENING WITH MOISTURE
AROUND AND WEAK IMPULSES SLIDING BY. STRONGER COLD FRONT WITH THE
WAVE TO THE WEST WILL APPROACH FRIDAY AND SHOULD PASS ACROSS THE
AREA FRIDAY NIGHT INTO EARLY SATURDAY PER THE FASTER EC. EXPECT PRE-
FRONTAL BAND OF SHRA TO AFFECT MUCH OF THE REGION BY FRIDAY
AFTERNOON WITH SOME ISOLATED TSRA POSSIBLE SOUTH AND SW SO RUNNING
WITH CHANCE TO LOW LIKELY POPS INTO FRIDAY EVENING. BOUNDARY LOOKS
TO GET FAR ENOUGH SE TO ALLOW DRYING ON SATURDAY WITH ONLY SOME
EARLY CLOUDS/-SHRA MAINLY NW AND CLEARING ELSW PENDING LATER RUNS.
GOOD SOUTH TO SW FLOW SHOULD FINALLY BRING TEMPS UP TO SPRING LEVELS
AND ALLOW THEM TO STAY THERE WITH HIGHS MOSTLY 70S EXCEPT COOLING TO
60S SATURDAY BEHIND THE FRONT. LOWS WELL ABOVE FREEZING AND PERHAPS
STAYING ABOVE 50 OUT EAST DURING MIDWEEK.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
AS OF 735 AM EDT SUNDAY...
DEALING WITH RAIN AND SNOW SHOWERS ACROSS MOST OF THE TERMINALS
THIS MORNING. ACROSS THE PIEDMONT INTENSITY LOOKS LIKE SO DO NOT
EXPECT ANY VSBY ISSUES. IN THE WEST WHERE THERE WILL BE
SNOW...BLOWING SNOW...VSBYS COULD DROP TO AROUND 1-2SM AT BLF/BCB
AND PERHAPS LWB.
WE WILL SEE THE AREA START TO DRY FROM THE SOUTHWEST TO THE
NORTHEAST LATER THIS MORNING ESPECIALLY THIS AFTERNOON AS THE
CLOSED LOW MOVES OFF THE MID ATLANTIC COAST. THE NORTHWEST WINDS
ARE GOING TO BE THE BIGGER ISSUE WITH SOME GUSTS OVER 50 KNOTS IN
THE HIGHER ELEVATIONS...BOONE NC FOR INSTANCE. BCB/ROA ARE IN THE
BEST CORRIDOR AS FAR AS TAFS GO FOR WINDS CLOSE TO 50 KNOTS...WITH
LESS IN THE WV MTNS AND LYH/DAN.
WINDS WIL BE WEAKENING AFTER 00Z...AS HIGH PRESSURE BUILDS IN FROM
THE WEST.
EXTENDED AVIATION DISCUSSION...
GENERALLY VFR CONDITIONS SUN NIGHT UNTIL THU OR FRI...WHEN A SLOW
MOVING FRONTAL SYSTEM WILL REACH THE AREA FROM THE WEST/NORTH AND
BRING INCREASING LIKELIHOOD OF MVFR CIGS...ESPECIALLY EASTERN WV.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...HIGH WIND WARNING UNTIL 10 PM EDT THIS EVENING FOR VAZ009-
012>020-022-032-033.
WINTER WEATHER ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR
VAZ018>020-024-035.
WIND ADVISORY UNTIL 10 PM EDT THIS EVENING FOR VAZ007-010-011-
023-024-034-035-043>047-058-059.
NC...HIGH WIND WARNING UNTIL 10 PM EDT THIS EVENING FOR NCZ001>003-
018-019.
WIND ADVISORY UNTIL 10 PM EDT THIS EVENING FOR NCZ004>006-020.
WV...WINTER WEATHER ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR
WVZ042>045.
WIND ADVISORY UNTIL 10 PM EDT THIS EVENING FOR WVZ042>045.
WINTER STORM WARNING UNTIL 4 PM EDT THIS AFTERNOON FOR WVZ042-
043-045.
&&
$$
SYNOPSIS...NF/WP
NEAR TERM...JH/WP
SHORT TERM...RCS
LONG TERM...JH
AVIATION...MBS/RAB/WP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
555 AM CDT SUN MAR 30 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 319 AM CDT SUN MAR 30 2014
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A DEEP TROUGH SOUTH OF THE GULF OF ALASKA...A VIGOROUS
SHORTWAVE TROUGH COMING INTO CENTRAL CALIFORNIA...AND A RIDGE AXIS
FROM TEXAS INTO THE FORECAST AREA. PROFILER AND VAD WIND DATA SHOWED
A CORRIDOR OF SOUTHWESTERLY 40-55 KT WINDS AT 925MB JUST TO THE WEST
OF THE RIDGE AXIS. THESE WINDS ARE PROPELLING WARMER AIR THAT WAS
OBSERVED OVER THE PLAINS YESTERDAY TOWARDS THE FORECAST AREA. ITS
WORTH NOTING HIGHS YESTERDAY WERE IN THE 60S TO LOW 70S FROM WESTERN
NORTH DAKOTA INTO OKLAHOMA...ASSOCIATED WITH 925MB TEMPS OF 10 TO
20C. CLOUD COVER MOSTLY OF THE SCATTERED CIRRUS VARIETY...REFLECTIVE
OF UPPER LEVEL MOISTURE STREAMING FROM THE PACIFIC ON WATER VAPOR.
AIRMASS ACROSS MUCH OF THE PLAINS AND THE FORECAST AREA VERY DRY PER
00Z SOUNDINGS...NOTED TOO FROM PRECIPITABLE WATER VALUES BETWEEN 0.2-
0.3 INCHES. AT THE SURFACE...THE SURFACE RIDGE THAT WAS OVER THE
AREA YESTERDAY HAS SHIFTED EAST TO OVER LAKE MICHIGAN...WHILE
PRESSURES ARE FALLING ALONG THE LEE OF THE ROCKIES. THE SURFACE
RIDGE HAS PUSHED ANY MEANINGFUL SURFACE MOISTURE...DEWPOINTS AT OR
ABOVE 40F...DOWN TO THE GULF OF MEXICO COAST.
SYNOPTICALLY...THE UPPER RIDGING PRESENT OVER THE FORECAST AREA
LOOKS TO PERSIST THROUGH TONIGHT...WITH A SHIFT TO THE EAST AFTER
MIDNIGHT. THE PUSH EAST TO THE RIDGE IS CAUSED BY THE VIGOROUS
SHORTWAVE LIFTING INTO THE FAR NORTHEAST COLORADO AREA BY 12Z
MONDAY. ITS ALSO WORTH NOTING THAT THE SHORTWAVE BECOMES NEGATIVELY
TILTED.
WITH THE FORECAST AREA PROGGED TO BE IN THE WARM SECTOR OF A
DEEPENING LOW COMING OUT OF COLORADO AND INTO CENTRAL NEBRASKA BY
12Z MONDAY...MUCH OF THE FORECAST CONCERN IS ON TEMPERATURES. 925MB
TEMPS ARE PROGGED TO CONTINUE TO CLIMB THROUGH THE DAY ON A BREEZY
SOUTH TO SOUTHWEST WIND...RISING FROM 1 TO 5C AT 12Z TO 9 TO 13C BY
00Z. THESE READINGS HOLD NEARLY STEADY FOR TONIGHT DUE TO PERSISTENT
25-35 KT SOUTH WINDS. COMBINATION OF THE AFOREMENTIONED WARM
ADVECTION AND SUNSHINE SHOULD EASILY PUSH HIGHS INTO THE 60S ALONG
AND SOUTHWEST OF I-94. NORTH OF I-94...SNOW PACK AND COOLER 925MB
TEMPS WILL HOLD HIGHS BACK INTO THE 50S. THE MIXING TODAY TOO WILL
BE LIMITED A LITTLE DUE TO SCT-BKN CIRRUS EMANATING FROM NEBRASKA
AREA CURRENTLY. WITH A LOW LEVEL JET IN PLACE TONIGHT...MOST
LOCATIONS SHOULD ONLY SEE LOWS IN THE 40S. THERE ARE INDICATIONS THE
TYPICAL COLD SPOTS MIGHT DECOUPLE OR AT LEAST SEE LIGHTER
WINDS...ALLOWING TEMPERATURES THERE TO DIP INTO THE UPPER 30S.
PRECIPITATION-WISE...PLENTIFUL DRY AIR IN PLACE AS SEEN AT 00Z LAST
EVENING WILL KEEP CONDITIONS DRY THROUGH THIS EVENING. AFTER
MIDNIGHT...THERE IS GOOD AGREEMENT AMONG MODELS FOR A WARM CONVEYOR
BELT OF PRECIPITATION TO DEVELOP OVER EASTERN NEBRASKA AND WESTERN
IOWA. MUCH OF THIS PRECIPITATION CORRELATES WITH ISENTROPIC LIFT ON
THE 305-310K SURFACES...OR AT PRESSURES ABOVE 700MB. IN ANY
EVENT...AT LEAST THROUGH TONIGHT...THE FORECAST AREA STAYS DRY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 319 AM CDT SUN MAR 30 2014
MUCH OF THE FOCUS IS ON THE MONDAY THROUGH TUESDAY PERIOD. IMPACTS
DESCRIBED BELOW...
SYNOPTICALLY...ATTENTION IS COMPLETELY ON THE VIGOROUS SHORTWAVE
TROUGH APPROACHING THE CENTRAL CALIFORNIA COAST. MODELS CONTINUE TO
CONVERGE ON A COMMON SOLUTION FOR HANDLING THIS NEGATIVE TILT
TROUGH...THOUGH THERE IS SOME SLIGHT TIMING SPREAD. MODEL CONSENSUS
SHOWS THE TROUGH LIFTING INTO SOUTHWEST MN BY 00Z TUESDAY...
NORTHWEST WI BY 12Z TUESDAY AND INTO ONTARIO BY 00Z WEDNESDAY. THE
NAM REMAINS THE FASTEST OF THE CONSENSUS AND SEEMS A LITTLE
SUSPICIOUS...SEEING THAT THE ECMWF HAS BEEN TRENDING SLOWER OVER THE
PAST FEW DAYS. GIVEN THE VIGOROUS NATURE OF THE SHORTWAVE...WOULD
SEEM A SLOWER AND DEEPER ROUTE WOULD BE THE WAY TO GO. REGARDING
THE SURFACE LOW...FOLLOWING THE SAME PREMISES...BELIEVE THE
SLOWER...DEEPER MORE WRAPPED SYSTEM PRESENTED BY THE
CANADIAN/UKMET/ECMWF IS MORE LIKELY COMPARED TO THE NAM AND EVEN
GFS. WPC HAS ALSO FAVORED THE SAME MODELS.
PRECIPITATION-WISE...THE WARM CONVEYOR BELT DEVELOPING OFF TO OUR
WEST LOOKS LIKELY TO MOVE INTO WESTERN PORTIONS OF THE FORECAST AREA
MONDAY MORNING. HARD TO SAY IF IT IS GOING TO PROGRESS INTO
WISCONSIN PRIOR TO 18Z SEEING THE DRIER NAM/ECMWF LOOK. THEREFORE
HAVE ONLY KEPT 20-40 PERCENT CHANCES 15-18Z. FOR THE AFTERNOON...
THERE ARE SIGNS THAT THE WARM CONVEYOR PRECIPITATION MAY FALL APART
AS IT MOVES INTO WISCONSIN...OR AT LEAST SHIFT NORTH INTO NORTHERN
WISCONSIN....ESPECIALLY IN THE CANADIAN MODELS. GFS 305-310K
ISENTROPIC LIFT PROGS SUGGEST THE SAME. THEREFORE...HAVE KEPT
PRECIPITATION CHANCES MOSTLY IN THE 20-50 PERCENT RANGE OUTSIDE
OF TAYLOR COUNTY WHERE PRECIPITATION IS MOST LIKELY. FOCUS THEN
SHIFTS WEST ON WHETHER SHOWERS OR STORMS CAN FIRE ALONG A COLD
FRONT / DRY LINE. THE GFS/CANADIAN/ECMWF/UKMET ALL INITIATE A SCT-
BKN LINE OF SHOWERS NEAR I-35 TOWARDS 00Z. HOWEVER...THERE ARE TWO
HUGE CONCERNS FOR THIS BEING A LINE OF SURFACE BASED CONVECTION...
FIRST IS A FAIRLY STOUT CAP AROUND 700MB...SECOND ARE SURFACE
DEWPOINTS WHICH MODELS TRY TO JUMP INTO THE LOW 50S. THE DEWPOINTS
SEEM WAY OVERDONE. NOW CANT RULE OUT THE LINE OF SHOWERS FORMING
MORE ABOVE THE CAP GIVEN FORCING FROM THE LEFT EXIT REGION ALONG
WITH DPVA WITH THE TROUGH. SINCE THERE IS NO CAPE ABOVE THE CAP
AND CONCERNED PRECIPITATION MAY NOT FORM AT ALL...REMOVED THE
THUNDER CHANCE. THIS SHOULD ALSO REDUCE THE CONCERN OF ANY
POSSIBLE SEVERE WEATHER. IF A LINE DOES FORM...IT LOOKS TO LIFT
NORTHEAST THROUGH THE AREA DURING THE EVENING. PRECIPITATION LOOKS
MORE LIKELY AFTER MIDNIGHT INTO TUESDAY MORNING OVER THE NORTHWEST
HALF OF THE AREA AS THE COLD CONVEYOR BELT WRAPS IN. MOST OF THIS
SHOULD BE A LIGHT SNOW WITH LITTLE ACCUMULATION. THIS SNOW WILL
TAPER OFF TUESDAY AFTERNOON WITH THE DEPARTURE OF THE SYSTEM.
TEMPERATURES...BEING IN THE WARM SECTOR ALL OF MONDAY WITH 9-13C
925MB READINGS...COMBINED WITH A WARMER START...THAT BREAK IN
PRECIPITATION DURING THE AFTERNOON TO ALLOW FOR MIXING AND BREEZY
SOUTH WINDS...HIGHS AGAIN SHOULD CLIMB INTO THE 60S AT MOST
LOCATIONS. SNOWPACK HOLDS TAYLOR DOWN INTO THE 50S. READINGS THEN
TANK MONDAY NIGHT AS THE COLD AIR WRAPS IN SOUTHWEST TO NORTHEAST.
MUCH COOLER HIGHS FOR TUESDAY...THOUGH SOUTHERN AREAS SHOULD CLIMB
INTO THE MID 40S AS THE COLD AIR DEPARTS.
WINDS...SOUTHERLY 925MB WINDS INCREASE THROUGH MONDAY AS THE
NEGATIVE TILT SHORTWAVE TROUGH APPROACHES. BY 21Z...MOST MODELS PROG
THEM AROUND 40 KT WHILE 850MB WINDS APPROACH 50-55 KT...STRONGEST
SOUTH OF I-90. DAYTIME MIXING SHOULD BE ENOUGH TO GIVE GUSTS OF 30-
35 KT...WITH A PRESSURE FALL CROSSING EAU CLAIRE GIVING SOME
ISALLOBARIC HELP. AN ADVISORY MAY BE NEEDED IF NAM/GFS MOMENTUM
TRANSFER PROGS ARE CORRECT...SUGGESTING 35-42 KT GUSTS. WITH THE
COLD SIDE OF THE SYSTEM...925MB WINDS ARE A LITTLE LESS...CLOSER TO
35 KT FOR MONDAY NIGHT INTO TUE MORNING. THESE SHOULD EASILY MIX TO
THE GROUND. MORE UNCERTAINTY EXISTS ON THE NEED FOR THE ADVISORY ON
THE COLD SIDE.
FOR TUESDAY NIGHT AND BEYOND...
NEXT ITEM OF INTEREST IS THE TROUGH CURRENTLY SOUTH OF THE GULF OF
ALASKA WHICH IS PROGGED TO END UP IN THE SOUTHWESTERN U.S. ON
WEDNESDAY. UPPER RIDGING BUILDS DOWNSTREAM AHEAD OF THE TROUGH...BUT
MOSTLY SOUTH OF THE FORECAST AREA. THIS KEEPS A COLDER LOW LEVEL
AIRMASS IN PLACE. MEANWHILE...ISENTROPIC LIFT OF GULF OF MEXICO
MOISTURE DOWNSTREAM OF THE UPPER TROUGH MAY SPREAD SOME
PRECIPITATION INTO SOUTHERN PORTIONS OF THE FORECAST AREA PER 30.00Z
GFS/GFS ENSEMBLES WEDNESDAY AND WEDNESDAY NIGHT. HOWEVER...30.00Z
CANADIAN AND ECMWF KEEP THE PRECIPITATION SOUTH OF THE FORECAST
AREA. HAVE SPLIT THE DIFFERENCE WHICH RESULTS IN MAINLY A DRY
FORECAST NORTH OF I-90 TO SOME 20-50 PERCENT CHANCES SOUTH. THURSDAY
COULD END UP BEING A MOSTLY DRY DAY. CONFIDENCE IS BEGINNING TO
INCREASE FOR PRECIPITATION THURSDAY NIGHT THROUGH FRIDAY. THIS IS
WHEN MODELS ARE IN GOOD AGREEMENT LIFTING THE TROUGH INTO THE
FORECAST AREA. WINTER WEATHER ADVISORIES REMAIN POSSIBLE...MOSTLY
DUE TO ACCUMULATING SNOW. DRIER WEATHER LOOKS TO MOVE IN FOR
SATURDAY AS THE SYSTEM DEPARTS. BELOW NORMAL TEMPERATURES ARE LIKELY
FOR MUCH OF TUESDAY NIGHT AND BEYOND GIVEN THE UPPER FLOW.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 555 AM CDT SUN MAR 30 2014
LOW LEVEL WIND SHEAR WILL OCCUR AT KRST THROUGH 15Z THIS MORNING
WITH SURFACE WINDS OUT OF THE SOUTH AT 16KTS...VEERING SOUTH/SOUTHWEST
INCREASING INTO THE 50 TO 55 KT RANGE AT 1500 FT. LLWS WILL
SUBSIDE LATER THIS MORNING. OTHERWISE PLAN ON BREEZY SOUTH WINDS
AT THE TAF SITES TODAY WITH VFR CONDITIONS EXPECTED. SCT-BKN 25KFT
CIRRUS WILL STREAM OVER THE REGION TODAY. PLAN ON VFR CONDITIONS
TONIGHT WITH CLOUDS GRADUALLY INCREASING LATE WITH CLOUD BASES
LOWERING TO AROUND 15KFT EARLY MONDAY MORNING. ISOLATED SHOWERS
ARE POSSIBLE AT THE TAF SITES AFTER 12Z MONDAY MORNING.
&&
.HYDROLOGY...
ISSUED AT 319 AM CDT SUN MAR 30 2014
BASED ON GAUGE READINGS ALONG THE KICKAPOO FOR THOSE THAT STILL HAVE
FLOOD WARNINGS...CONFIDENCE IS DECREASING THAT THEY WILL MAKE IT TO
FLOOD. READSTOWN HAS STARTED FALLING...WHEN IT SHOULD STILL BE
RISING. IF TRENDS CONTINUE...THE WARNINGS MAY BE CANCELLED.
FOCUS THEN SHIFTS TO THE BLACK...BUFFALO AND TREMPEALEAU RIVERS. THE
WARM UP OCCURRING TODAY AND PERSISTING INTO MONDAY EVENING...
FEATURING HIGHS IN THE 55-65 RANGE AND LOWS IN THE 38-48 RANGE ALONG
WITH BREEZY SOUTH WINDS...WILL HELP RAPIDLY MELT THE SNOW PACK THAT
IS IN PLACE ALONG AND NORTH OF HIGHWAY 10. THIS RUNOFF WILL MAKE
FLOODING A POSSIBILITY DURING THE WEEK. ON A POSITIVE NOTE...THE
PRECIPITATION FROM THE SYSTEM MOVING THROUGH THE AREA MONDAY AND
MONDAY NIGHT CONTINUES TO LOOK LESS AND LESS. AT THIS POINT...RAIN
DOES NOT APPEAR TO BE MUCH OF A FACTOR TO THE RIVERS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...WETENKAMP
HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
1053 AM PDT SUN MAR 30 2014
.SYNOPSIS...ISOLATED SHOWERS ARE POSSIBLE OVER THE HILLS ON SUNDAY
AFTERNOON. OTHERWISE SUNDAY WILL BE A DRY DAY UNDER PARTLY CLOUDY
SKIES. A ROBUST COLD FRONT WILL SPREAD RAIN ACROSS THE REGION ON
MONDAY...ALONG WITH GUSTY WINDS. SHOWERS AND POSSIBLE
THUNDERSTORMS ARE FORECAST FROM MONDAY NIGHT THROUGH TUESDAY
EVENING. SHOWERS MAY LINGER OVER THE SOUTHERN PART OF THE REGION
INTO WEDNESDAY. RAINFALL LATER IN THE WEEK NOW APPEARS LESS LIKELY.
&&
.DISCUSSION...AS OF 9:08 AM PDT SUNDAY...CURRENT FORECAST IS
PRETTY MUCH ON TRACK. THERE WERE SOME ISOLATED SHOWERS BEFORE
SUNRISE BUT THOSE HAVE ENDED FOR THE MOST PART. SKIES ARE PARTLY
CLOUDY THIS MORNING IN THE WAKE OF YESTERDAYS FRONTAL PASSAGE AND
ASSOCIATED RAINFALL. THERE WAS SOME DENSE FOG EARLIER IN THE SONOMA
VALLEYS BUT THAT`S LIFTING AS WELL. THE 12Z KOAK SOUNDING IS
SOMEWHAT UNSTABLE AND GIVEN CURRENT CUMULUS DEVELOPMENT EXPECT WE`LL
SEE CLOUDS START TO BILLOW UP OVER THE HILLS FROM MIDDAY THROUGH
AFTERNOON WITH COLDER AIR ALOFT. CURRENT FORECAST SHOWS SLIGHT
CHANCE OF SHOWERS THIS AFTERNOON MAINLY OVER OUR EASTERN/INLAND
HILLS AND THAT LOOKS LIKE A GOOD FORECAST. NAM AND HRRR MODELS
SPIT OUT SOME LIGHT CONVECTIVE QPF NEAR MOUNT HAMILTON LATER THIS
AFTERNOON AND THAT OFTEN OCCURS IN THESE TYPE OF PATTERNS. WILL
KEEP THE KMUX-88D SPINNING IN VCP 12 FOR THE TIME BEING. OTHERWISE
EXPECT A PARTLY CLOUDY AND PLEASANT SUNDAY AFTERNOON WITH HIGHS
INTO THE LOW AND MID 60S.
MAIN FORECAST FOCUS WILL BE ON MONDAYS COLD FRONT AND 12Z MODELS
ARE STAYING CONSISTENT WITH LIGHT RAIN INTO THE NORTH BAY BEFORE
NOON BUT THE MAIN RAIN BAND REALLY IMPACTING THE AFTERNOON AND
EVENING COMMUTE. THE STORM IS LOOKING GOOD ON SATELLITE RIGHT NOW
OUT NEAR 45N/140W WITH PLENTY OF COLD AIR AND IMPLIED JET ENERGY.
SEE NO REASON TO CHANGE INHERITED FORECASTS AND NOT PLANNING MANY
CHANGES FOR AFTERNOON PACKAGE. AFTER BRIEF PERIOD OF FRONTAL RAINS
MONDAY AFTERNOON AND EVENING...EXPECT A SHORT LULL IN THE PRECIP.
THEN SHOWERS AND T-STORMS SHOULD BECOME NUMEROUS LATER MONDAY
NIGHT INTO TUESDAY AS COLD CORE APPROACHES. SHOWERS WILL LINGER
INTO WEDS MORNING FOR THE MONTEREY BAY REGION. MARCH GOING OUT
LIKE A LION.
&&
.PREV DISCUSSION...AS OF 3:30 AM PDT SUNDAY...WIDELY SCATTERED SHOWERS
CONTINUE ACROSS THE SOUTHERN HALF OF THE CWA EARLY THIS
MORNING. RADAR INDICATES THESE SHOWERS ARE EITHER DISSIPATING OR
MOVING TO THE SOUTHEAST OUT OF OUR AREA. THUS...IT LOOKS LIKELY THAT
ALL RAIN WILL END BY DAYBREAK AS FORECAST BY THE MODELS. SKIES ARE
CLEARING FROM NORTH TO SOUTH AND PATCHY FOG HAS FORMED IN THE NORTH
BAY VALLEYS. THE LOW LEVELS PROBABLY ARE NOT YET STABLE ENOUGH TO
SUPPORT FOG FORMATION OUTSIDE THE ISOLATED NORTH BAY VALLEY
LOCATIONS THIS MORNING. CLOUDS SHOULD MOSTLY CLEAR BY DAYBREAK AND
THE BALANCE OF THE DAY WILL BE PARTLY TO MOSTLY SUNNY. SOME CU
BUILDUPS ARE LIKELY OVER THE HILLS IN THE AFTERNOON...AND ISOLATED
SHOWERS ARE POSSIBLE OVER THE INLAND HILLS OF THE SF BAY AREA AS
FORECAST BY BOTH THE NAM AND GFS. AFTERNOON HIGHS WILL MOSTLY BE
AROUND 60...A BIT COOLER THAN NORMAL.
EARLY MORNING SATELLITE IMAGERY SHOWS A COLD UPPER TROUGH IN THE
NORTHEAST PACIFIC...CENTERED NEAR 45N/140W. THIS SYSTEM IS
FORECAST TO DROP SOUTHEAST OVER THE NEXT FEW DAYS AND BRING
PERIODS OF PRECIPITATION TO OUR REGION DURING THE FIRST HALF OF
THE WORK WEEK...ALONG WITH COOL TEMPERATURES...GUSTY
WINDS...POSSIBLE THUNDERSTORMS...AND SNOW ON THE HIGHER HILLS. THE
LEADING EDGE OF THIS SYSTEM WILL BE A RELATIVELY STRONG COLD FRONT
THAT WILL SPREAD RAIN ACROSS OUR AREA ON MONDAY AND MONDAY
EVENING. BRIEF HEAVY RAIN COULD OCCUR AROUND THE TIME OF FRONTAL
PASSAGE...MAINLY LATE MONDAY AFTERNOON AND EARLY MONDAY EVENING.
LOCAL WIND GUSTS BETWEEN 30 AND 40 MPH ARE POSSIBLE ALONG THE
FRONT.
AFTER THE COLD FRONT MOVES THROUGH...A COLD UPPER LOW OFFSHORE
WILL SLIDE GRADUALLY TO THE SOUTHEAST...EITHER TRACKING DIRECTLY
ACROSS THE SF BAY AREA BY LATE TUESDAY AND TUESDAY NIGHT AS
FORECAST BY MOST MODELS...OR TRACKING OFFSHORE PARALLEL TO THE
COAST AS DEPICTED BY THE GFS. REGARDLESS OF THE LOW CENTER`S EXACT
TRACK...THE INSTABILITY GENERATED BY THIS COLD SYSTEM WILL
TRIGGER WIDESPREAD SHOWER ACTIVITY ACROSS OUR AREA FROM LATE
MONDAY NIGHT THROUGH TUESDAY NIGHT. THUNDERSTORMS ARE ALSO
POSSIBLE GIVEN THE EXPECTED STEEP LAPSE RATES AND GOOD LOW LEVEL
SHEAR. SNOW LEVELS WILL DROP TO 4000 FEET BY LATE MONDAY AFTER
COLD FRONTAL PASSAGE...AND THEN AS LOW AS 3500 FEET FROM MONDAY
NIGHT THROUGH TUESDAY NIGHT AS AN UNSEASONABLY COOL AIRMASS
SPREADS ACROSS OUR AREA. HEAVIER SHOWERS COULD BRIEFLY PRODUCE
EVEN LOWER SNOW LEVELS ALONG WITH SMALL HAIL. THE LATEST MODELS
KEEP SCATTERED SHOWER ACTIVITY GOING ACROSS THE SOUTHERN PART OF
OUR AREA INTO WEDNESDAY.
RAINFALL TOTALS FROM MONDAY THROUGH WEDNESDAY ARE CURRENTLY
FORECAST TO RANGE FROM A HALF INCH TO AN INCH IN MOST
AREAS...EXCEPT ONE TO TWO INCHES POSSIBLE IN THE COASTAL HILLS.
SOMEWHAT LESSER RAIN TOTALS WOULD OCCUR IF THE LOW CENTER TRACKS
OFFSHORE AS FORECAST BY THE GFS. SNOW ACCUMULATION IS LIKELY IN
THE HILLS ABOVE 4000 FEET WITH A DUSTING OF SNOW POSSIBLE DOWN TO
3500 FEET.
TEMPERATURES WILL BE UNSEASONABLY COOL FROM MONDAY THROUGH
WEDNESDAY WITH HIGH TEMPERATURES EXPECTED TO BE MOSTLY IN THE
50S AND LOWER 60S...AND ONLY IN THE UPPER 30S AND 40S IN
THE HILLS.
A SPECIAL WEATHER STATEMENT WILL BE ISSUED SHORTLY TO SUMMARIZE
THE EXPECTED WEATHER CONDITIONS DURING THE FIRST HALF OF THE
WEEK...INCLUDING PERIODS OF BRIEF HEAVY RAIN...GUSTY
WINDS...POSSIBLE THUNDERSTORMS...COOL TEMPS...AND SNOW IN THE
HILLS.
A SYSTEM DUE IN LATER IN THE WEEK IS LOOKING LESS IMPRESSIVE WITH
EACH NEW MODEL RUN. THE GFS AND GEM MODELS BOTH WASH THIS SYSTEM
OUT COMPLETELY AS IT APPROACHES THE COAST ON THURSDAY. THE ECMWF
STILL BRINGS SOME PRECIP TO COASTAL AREAS LATE THURSDAY INTO
FRIDAY...BUT EVEN THIS MODEL IS TRENDING DRIER. POPS HAVE BEEN
REDUCED LATE IN THE WEEK...BUT MAY NEED TO BE REDUCED FURTHER
GIVEN RECENT MODEL TRENDS.
&&
.AVIATION...AS OF 10:45 AM PDT SUNDAY...A MOIST AIRMASS REMAINS IN
PLACE ACROSS THE REGION AND WILL BRING ABOUT SCT/BKN CLOUDS
THROUGH THIS EVENING. OVERALL...EXPECTING CIGS TO REMAIN ABOVE
3KFT...YET CANNOT RULE OUT CIGS BRIEFLY DROPPING TO MVFR LEVELS
THIS AFTERNOON. WESTERLY WINDS INCREASE THIS AFTERNOON AND WILL
CONTINUE THROUGH THE EARLY EVENING...THEN DIMINISH TONIGHT.
CLOUDS INCREASE AND WINDS TURN SOUTHERLY AHEAD OF AN APPROACHING
STORM SYSTEM MONDAY MORNING.
VICINITY OF KSFO...GENERALLY VFR...CIGS SCT-BKN035 BY EARLY
AFTERNOON WITH WEST WINDS INCREASING TO 12 TO 15KT. WINDS
DIMINISH TONIGHT WITH A DECREASE IN CLOUD COVER. SOUTH WINDS
DEVELOP EARLY MONDAY MORNING WITH LIGHT RAIN OR SHOWERS POSSIBLE
BY MONDAY AFTERNOON. MODERATE TO HIGH CONFIDENCE.
KSFO BRIDGE APPROACH...GENERALLY SIMILAR TO SFO...CIGS SLIGHTLY
LOWER AT SCT-BKN025 THROUGH THE AFTERNOON.
MONTEREY BAY AREA TERMINALS...GENERALLYVFR...CIGS SCT-BKN035 BY
EARLY AFTERNOON. WEST WINDS WILL APPROACH 12 KT THIS AFTERNOON
BEFORE DIMINISHING TONIGHT. WEAK SOUTHERLY FLOW DEVELOPS MONDAY
MORNING. MODERATE TO HIGH CONFIDENCE.
MODERATE CONFIDENCE.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...SCA...ROUGH BAR ADVISORY FOR SF BAR
&&
$$
PUBLIC FORECAST: RWW
AVIATION: RGASS
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AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
908 AM PDT SUN MAR 30 2014
.SYNOPSIS...ISOLATED SHOWERS ARE POSSIBLE OVER THE HILLS ON SUNDAY
AFTERNOON. OTHERWISE SUNDAY WILL BE A DRY DAY UNDER PARTLY CLOUDY
SKIES. A ROBUST COLD FRONT WILL SPREAD RAIN ACROSS THE REGION ON
MONDAY...ALONG WITH GUSTY WINDS. SHOWERS AND POSSIBLE
THUNDERSTORMS ARE FORECAST FROM MONDAY NIGHT THROUGH TUESDAY
EVENING. SHOWERS MAY LINGER OVER THE SOUTHERN PART OF THE REGION
INTO WEDNESDAY. RAINFALL LATER IN THE WEEK NOW APPEARS LESS LIKELY.
&&
.DISCUSSION...AS OF 9:08 AM PDT SUNDAY...CURRENT FORECAST IS
PRETTY MUCH ON TRACK. THERE WERE SOME ISOLATED SHOWERS BEFORE
SUNRISE BUT THOSE HAVE ENDED FOR THE MOST PART. SKIES ARE PARTLY
CLOUDY THIS MORNING IN THE WAKE OF YESTERDAYS FRONTAL PASSAGE AND
ASSOCIATED RAINFALL. THERE WAS SOME DENSE FOG EARLIER IN THE SONOMA
VALLEYS BUT THAT`S LIFTING AS WELL. THE 12Z KOAK SOUNDING IS
SOMEWHAT UNSTABLE AND GIVEN CURRENT CUMULUS DEVELOPMENT EXPECT WE`LL
SEE CLOUDS START TO BILLOW UP OVER THE HILLS FROM MIDDAY THROUGH
AFTERNOON WITH COLDER AIR ALOFT. CURRENT FORECAST SHOWS SLIGHT
CHANCE OF SHOWERS THIS AFTERNOON MAINLY OVER OUR EASTERN/INLAND
HILLS AND THAT LOOKS LIKE A GOOD FORECAST. NAM AND HRRR MODELS
SPIT OUT SOME LIGHT CONVECTIVE QPF NEAR MOUNT HAMILTON LATER THIS
AFTERNOON AND THAT OFTEN OCCURS IN THESE TYPE OF PATTERNS. WILL
KEEP THE KMUX-88D SPINNING IN VCP 12 FOR THE TIME BEING. OTHERWISE
EXPECT A PARTLY CLOUDY AND PLEASANT SUNDAY AFTERNOON WITH HIGHS
INTO THE LOW AND MID 60S.
MAIN FORECAST FOCUS WILL BE ON MONDAYS COLD FRONT AND 12Z MODELS
ARE STAYING CONSISTENT WITH LIGHT RAIN INTO THE NORTH BAY BEFORE
NOON BUT THE MAIN RAIN BAND REALLY IMPACTING THE AFTERNOON AND
EVENING COMMUTE. THE STORM IS LOOKING GOOD ON SATELLITE RIGHT NOW
OUT NEAR 45N/140W WITH PLENTY OF COLD AIR AND IMPLIED JET ENERGY.
SEE NO REASON TO CHANGE INHERITED FORECASTS AND NOT PLANNING MANY
CHANGES FOR AFTERNOON PACKAGE. AFTER BRIEF PERIOD OF FRONTAL RAINS
MONDAY AFTERNOON AND EVENING...EXPECT A SHORT LULL IN THE PRECIP.
THEN SHOWERS AND T-STORMS SHOULD BECOME NUMEROUS LATER MONDAY
NIGHT INTO TUESDAY AS COLD CORE APPROACHES. SHOWERS WILL LINGER
INTO WEDS MORNING FOR THE MONTEREY BAY REGION. MARCH GOING OUT
LIKE A LION.
&&
.PREV DISCUSSION...AS OF 3:30 AM PDT SUNDAY...WIDELY SCATTERED SHOWERS
CONTINUE ACROSS THE SOUTHERN HALF OF THE CWA EARLY THIS
MORNING. RADAR INDICATES THESE SHOWERS ARE EITHER DISSIPATING OR
MOVING TO THE SOUTHEAST OUT OF OUR AREA. THUS...IT LOOKS LIKELY THAT
ALL RAIN WILL END BY DAYBREAK AS FORECAST BY THE MODELS. SKIES ARE
CLEARING FROM NORTH TO SOUTH AND PATCHY FOG HAS FORMED IN THE NORTH
BAY VALLEYS. THE LOW LEVELS PROBABLY ARE NOT YET STABLE ENOUGH TO
SUPPORT FOG FORMATION OUTSIDE THE ISOLATED NORTH BAY VALLEY
LOCATIONS THIS MORNING. CLOUDS SHOULD MOSTLY CLEAR BY DAYBREAK AND
THE BALANCE OF THE DAY WILL BE PARTLY TO MOSTLY SUNNY. SOME CU
BUILDUPS ARE LIKELY OVER THE HILLS IN THE AFTERNOON...AND ISOLATED
SHOWERS ARE POSSIBLE OVER THE INLAND HILLS OF THE SF BAY AREA AS
FORECAST BY BOTH THE NAM AND GFS. AFTERNOON HIGHS WILL MOSTLY BE
AROUND 60...A BIT COOLER THAN NORMAL.
EARLY MORNING SATELLITE IMAGERY SHOWS A COLD UPPER TROUGH IN THE
NORTHEAST PACIFIC...CENTERED NEAR 45N/140W. THIS SYSTEM IS
FORECAST TO DROP SOUTHEAST OVER THE NEXT FEW DAYS AND BRING
PERIODS OF PRECIPITATION TO OUR REGION DURING THE FIRST HALF OF
THE WORK WEEK...ALONG WITH COOL TEMPERATURES...GUSTY
WINDS...POSSIBLE THUNDERSTORMS...AND SNOW ON THE HIGHER HILLS. THE
LEADING EDGE OF THIS SYSTEM WILL BE A RELATIVELY STRONG COLD FRONT
THAT WILL SPREAD RAIN ACROSS OUR AREA ON MONDAY AND MONDAY
EVENING. BRIEF HEAVY RAIN COULD OCCUR AROUND THE TIME OF FRONTAL
PASSAGE...MAINLY LATE MONDAY AFTERNOON AND EARLY MONDAY EVENING.
LOCAL WIND GUSTS BETWEEN 30 AND 40 MPH ARE POSSIBLE ALONG THE
FRONT.
AFTER THE COLD FRONT MOVES THROUGH...A COLD UPPER LOW OFFSHORE
WILL SLIDE GRADUALLY TO THE SOUTHEAST...EITHER TRACKING DIRECTLY
ACROSS THE SF BAY AREA BY LATE TUESDAY AND TUESDAY NIGHT AS
FORECAST BY MOST MODELS...OR TRACKING OFFSHORE PARALLEL TO THE
COAST AS DEPICTED BY THE GFS. REGARDLESS OF THE LOW CENTER`S EXACT
TRACK...THE INSTABILITY GENERATED BY THIS COLD SYSTEM WILL
TRIGGER WIDESPREAD SHOWER ACTIVITY ACROSS OUR AREA FROM LATE
MONDAY NIGHT THROUGH TUESDAY NIGHT. THUNDERSTORMS ARE ALSO
POSSIBLE GIVEN THE EXPECTED STEEP LAPSE RATES AND GOOD LOW LEVEL
SHEAR. SNOW LEVELS WILL DROP TO 4000 FEET BY LATE MONDAY AFTER
COLD FRONTAL PASSAGE...AND THEN AS LOW AS 3500 FEET FROM MONDAY
NIGHT THROUGH TUESDAY NIGHT AS AN UNSEASONABLY COOL AIRMASS
SPREADS ACROSS OUR AREA. HEAVIER SHOWERS COULD BRIEFLY PRODUCE
EVEN LOWER SNOW LEVELS ALONG WITH SMALL HAIL. THE LATEST MODELS
KEEP SCATTERED SHOWER ACTIVITY GOING ACROSS THE SOUTHERN PART OF
OUR AREA INTO WEDNESDAY.
RAINFALL TOTALS FROM MONDAY THROUGH WEDNESDAY ARE CURRENTLY
FORECAST TO RANGE FROM A HALF INCH TO AN INCH IN MOST
AREAS...EXCEPT ONE TO TWO INCHES POSSIBLE IN THE COASTAL HILLS.
SOMEWHAT LESSER RAIN TOTALS WOULD OCCUR IF THE LOW CENTER TRACKS
OFFSHORE AS FORECAST BY THE GFS. SNOW ACCUMULATION IS LIKELY IN
THE HILLS ABOVE 4000 FEET WITH A DUSTING OF SNOW POSSIBLE DOWN TO
3500 FEET.
TEMPERATURES WILL BE UNSEASONABLY COOL FROM MONDAY THROUGH
WEDNESDAY WITH HIGH TEMPERATURES EXPECTED TO BE MOSTLY IN THE
50S AND LOWER 60S...AND ONLY IN THE UPPER 30S AND 40S IN
THE HILLS.
A SPECIAL WEATHER STATEMENT WILL BE ISSUED SHORTLY TO SUMMARIZE
THE EXPECTED WEATHER CONDITIONS DURING THE FIRST HALF OF THE
WEEK...INCLUDING PERIODS OF BRIEF HEAVY RAIN...GUSTY
WINDS...POSSIBLE THUNDERSTORMS...COOL TEMPS...AND SNOW IN THE
HILLS.
A SYSTEM DUE IN LATER IN THE WEEK IS LOOKING LESS IMPRESSIVE WITH
EACH NEW MODEL RUN. THE GFS AND GEM MODELS BOTH WASH THIS SYSTEM
OUT COMPLETELY AS IT APPROACHES THE COAST ON THURSDAY. THE ECMWF
STILL BRINGS SOME PRECIP TO COASTAL AREAS LATE THURSDAY INTO
FRIDAY...BUT EVEN THIS MODEL IS TRENDING DRIER. POPS HAVE BEEN
REDUCED LATE IN THE WEEK...BUT MAY NEED TO BE REDUCED FURTHER
GIVEN RECENT MODEL TRENDS.
&&
.AVIATION...AS OF 4:46 AM PDT SUNDAY...COOL UNSTABLE AIR IS
FILTERING IN BEHIND A DEPARTING COLD FRONT THIS MORNING. SKIES
WILL BECOME VFR TODAY AS SHOWER ACTIVITY TAPERS OFF. MOISTURE AND
LINGERING INSTABILITY MAY RESULT IN ISOLATED THUNDERSTORMS OVER
LOCAL RIDGE LINES LATE THIS MORNING INTO THE AFTERNOON HOURS.
THESE THUNDERSTORMS SHOULD NOT IMPACT THE TERMINALS.
VICINITY OF KSFO...VFR...WITH CUMULUS POPPING UP CREATING CIGS
SCT-BKN035 BY MID MORNING. WEST WINDS WILL INCREASE TO 15 TO 20 KT
THIS AFTERNOON.
MODERATE TO HIGH CONFIDENCE.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...MVFR CIGS WITH OCCASIONAL SHOWERS
THIS MORNING WILL GIVE WAY TO VFR SCT-BKN035 BY MID TO LATE
MORNING. WEST WINDS WILL REACH 10 TO 15 KT THIS AFTERNOON.
MODERATE CONFIDENCE.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...SCA...ROUGH BAR ADVISORY FOR SF BAR
&&
$$
PUBLIC FORECAST: RWW
AVIATION: LARRY
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AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1106 AM MDT SUN MAR 30 2014
.UPDATE...
ISSUED AT 1057 AM MDT SUN MAR 30 2014
DENSE MID AND HIGH CLOUD COVER INHIBITING DEEPER MIXING SO FAR
THIS MORNING WITH STRONG WINDS SLOW TO MATERIALIZE.
HOWEVER...STILL EXPECT A PERIOD OF STRONGER WINDS TO DEVELOP THIS
AFTERNOON. LATEST HRRR RUNS INDICATE DENSER CLOUD COVER WILL BE
ERODING AND BREAKING UP AFTER 2 PM MDT THIS AFTERNOON...AND ONCE
THIS BECOMES REALITY...DEEPER MIXING WILL QUICKLY DRIVE DOWN 50
PLUS KNOTS OF WIND ALOFT...WHICH MORNING SOUNDING AND PROFILERS
ALL INDICATED. ONCE WINDS GET MOVING IN NORTHERN ARIZONA...THE
BLOWING DUST UP INTO THE FOUR CORNERS WILL ALSO BE MOVING IN...SO
NO CHANGES TO CURRENT WIND HIGHLIGHTS. WILL EVALUATE SNOW
POTENTIAL LATER TODAY FOR ANY POSSIBLE EXPANSION OF WINTER
HIGHLIGHTS TONIGHT.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 505 AM MDT SUN MAR 30 2014
03Z HAND ANALYSIS SHOWED THE COLD FRONT AND ASSOCIATED SURFACE
LOW STRETCHED FROM THE PANHANDLE OF IDAHO TO THE CENTRAL NV/UT
BORDER...THEN BACK ACROSS SOUTHERN CALIFORNIA. WATER VAPOR SHOWING
THE NEXT UPSTREAM SYSTEM DIGGING INTO CENTRAL CALIFORNIA EARLY
THIS MORNING WITH A DEVELOPING BAROCLINIC LEAF OVER THE WESTERN
GREAT BASIN. WINDS BACKING MORE SOUTHERLY AND STRENGTHENING UNDER
THIS FEATURE WHICH IS KEEPING THE FRONT WELL TO THE WEST. PACIFIC
MOISTURE IS ALSO WRAPPING INTO THE SYSTEM AND MODELS ARE
CONSISTENT IN KEEPING THE DEEPER MOISTURE PINNED TO THE FRONT.
KGJT RAOB STILL SHOWED WELL BELOW PWAT AT .20. THIS MOISTURE IS
WELL ELEVATED AND WITH A DEEP MIXED LAYER EXPECTED AHEAD OF THE
APPROACHING FRONT AND SYSTEM THE INGREDIENTS ARE IN PLACE FOR A
VERY WINDY DAY ACROSS THE REGION. INVERTED V PROFILES WILL ONLY
ENHANCE WIND GUSTS TO THE SURFACE AS VIRGA AND LIGHT SHOWERS
DEVELOP THROUGH THE LATE MORNING HOURS WITH VERY BROAD ASCENT IN
PLACE. WINDS ATOP THE MIXED LAYER ARE STILL THE STRONGEST IN THE
SOUTHWEST CWA...WHICH IS WHERE CLOUDS LOOK THE THINNEST. CURRENT
ADVISORIES LOOK ON TRACK AS WINDS ARE EXPECTED TO GUST IN THE 45
TO 55 MPH RANGE TODAY. I DID ADD A BLOWING DUST ADVISORY FOR 4
CORNERS AREA WHERE LIMITED VISIBILITY WAS OBSERVED DURING THE LAST
WIND EVENT. DO NOT EXPECT SIGNIFICANT PRECIPITATION TO BE A THREAT
UNTIL THE FRONT ENTERS THE NORTHWEST CWA BY MID AFTERNOON.
COMPRESSIONAL HEATING AHEAD OF THE FRONT SEEMS IMPLIED BY LOW
LEVEL THERMAL RIDGE ACROSS THE CO/UT BORDER. CLOUDS/VIRGA MAY
HAMPER FULL HEATING BUT DECIDED TO PUSH SOME TEMPERATURES UP
TOWARD THE WARMER MET GUIDANCE NUMBERS.
PRECIPITATION LOOKS TO BLOSSOM THROUGH THE LATE AFTERNOON AND
EVENING AS THE FRONT WILL BE WORKING EASTWARD AND ASCENT FROM THE
PASSING TROUGH MOVES OVERHEAD. INSTABILITY AND MOISTURE NEAR THE
FRONT HAS THE BEST CHANCE FOR POPPING SOME THUNDERSTORMS IN THE
NORTHWEST HIGH PLATEAUS...WITH A THREAT OF SEVERE GUSTS IN PART DUE
TO STORM MOTIONS NEAR 50 MPH. CONSIDERED THIS AREAS FOR WIND ADVZY
AS WELL BUT WITH THICKER CLOUD COVER THROUGH THE DAY CONFIDENCE
STILL NOT THERE. GUSTY WINDS STILL EXPECTED BEHIND THE FRONT AS
SUBSIDENCE FROM BEHIND THE QUICKLY MOVING TROF MOVES IN AND COLD
ADVECTION ENHANCES MOMENTUM X-FER DOWNWARD. STRONG SOUTHWEST TO WEST
THEN NORTHWEST FLOW INTO THE NORTHWEST MOUNTAINS WILL BE
SUPPLEMENTED BY THE FRONTAL LIFTING/INSTABILITY/AND ASCENT THROUGH
THE EVENING AND SNOW RATES WILL BE PICKING UP. SNOW WILL BE FAIRLY
DENSE BUT BLOWING WILL BE LIKELY AS GUSTS OVER 40MPH CONTINUE
THROUGH THE EARLY MORNING HOURS. THE WINTER HEADLINES LOOK ON TRACK
AND THOUGH SNOW LEVEL REACH THE VALLEYS...AMOUNTS SHOULD BE IN THE
1-3 INCH RANGE. DRIER AIR AND SUBSIDENCE THROUGH THE NIGHT CLEARS
ALL BUT THE NORTHERN DIVIDE MOUNTAINS WHERE OROGRAPHICS BECOME MORE
FAVORABLE THROUGH MONDAY MORNING. COOLER TEMPERATURES WILL MOVE IN
FOR MONDAY...BUT WINDS WILL BE SUBSIDING AS RIDGING TEMPORARILY
BUILDS IN AHEAD OF THE NEXT TROF DEVELOPING TO THE WEST.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 505 AM MDT SUN MAR 30 2014
DIRTY SHORTWAVE RIDGE IN PLACE MONDAY NIGHT WITH PACIFIC MOISTURE
AHEAD OF A STRONG PACIFIC STORM GENERATING SOME LIGHT OVERRUNNING
ACROSS THE NORTH WHICH WILL INCREASE TUESDAY. TIGHTENING GRADIENT
WILL BRING STRONG WINDS AGAIN TUESDAY AFTERNOON/EVENING.
UNSETTLED CONDITIONS CONTINUE THROUGH MIDWEEK AS THE PACIFIC LOW
SLOWLY DRIFTS ACROSS THE GREAT BASIN...THEN ACROSS THE FORECAST
AREA. EXTENDED MODEL AGREEMENT NOT TERRIFIC WITH THIS SYSTEM SO
KEPT POPS FAIRLY WIDESPREAD. THERE IS A CHANCE FOR SOME MOUNTAIN
SNOW HIGHLIGHTS DURING THIS PERIOD...BUT GIVEN MODEL SPREAD HARD
TO SPECIFY WHERE AND WHEN.
LOTS OF SPREAD IN THE GFS ENSEMBLES AT THE END OF THE WEEK AND THE
OPERATIONAL GFS AND ECMWF NOT IN VERY GOOD AGREEMENT. EC POINTS TO
A DRIER FRIDAY BENEATH A SHORTWAVE RIDGE WHILE GFS INDICATED A
WEAK SHORTWAVE TO KEEP CONDITIONS UNSETTLED. BY SATURDAY...BOTH
SOLUTIONS INDICATED ANOTHER MODERATELY DEEP TROUGH WILL SETTLE
OVER THE AREA FOR CONTINUED ACTIVE SPRING WEATHER.
EXPECT COOLER THAN NORMAL TEMPERATURES THROUGHOUT THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1057 AM MDT SUN MAR 30 2014
GUSTY SOUTHWEST WINDS WILL CONTINUE TO STRENGTHEN THROUGH THIS
AFTERNOON WITH PEAK SPEEDS EXCEEDING 50 KTS ACROSS THE VALLEYS
WITH UP TO 60 KTS ACROSS THE HIGHER MOUNTAINS. THE STRONGEST WINDS
WILL ARRIVE AROUND 21Z THIS AFTERNOON AS DENSE CLOUD COVER ERODES
AND ALLOWS FOR DEEPER MIXING. AREAS OF BLOWING DUST WILL LOWER
VISIBILITY INTO MVFR THRESHOLDS AT TIMES. RAIN AND SNOW DEVELOPS
BY THIS EVENING AS WINDS GRADUALLY DIMINISH. MOUNTAIN PEAKS WILL
BECOME OBSCURED AS SHOWERS INCREASE IN COVERAGE AND INTENSITY.
CONDITIONS IMPROVE FROM WEST TO EAST AFTER 12Z MONDAY MORNING.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WIND ADVISORY UNTIL 9 PM MDT THIS EVENING FOR COZ003-006-007-009-
011-017>022.
BLOWING DUST ADVISORY UNTIL 9 PM MDT THIS EVENING FOR COZ021.
WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO 9 AM MDT
MONDAY FOR COZ004-010-013.
UT...WIND ADVISORY UNTIL 9 PM MDT THIS EVENING FOR UTZ022-025-027>029.
BLOWING DUST ADVISORY UNTIL 9 PM MDT THIS EVENING FOR UTZ022.
&&
$$
UPDATE...JDC
SHORT TERM...15
LONG TERM...NL
AVIATION...JDC
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
401 PM EDT SUN MAR 30 2014
.SYNOPSIS...
A LOW PRESSURE SYSTEM EAST OF NEW JERSEY WILL DRIFT SLOWLY OFFSHORE
TONIGHT. A HIGH PRESSURE SYSTEM WILL THEN BUILD IN FOR MONDAY NIGHT
AND TUESDAY. ANOTHER LOW PRESSURE SYSTEM WILL TRACK THROUGH THE
GREAT LAKES AND EASTERN CANADA WITH ITS ASSOCIATED COLD FRONT
PASSING ACROSS THE AREA EARLY WEDNESDAY. THE FRONT IS THEN FORECAST
TO STALL JUST SOUTH OF THE AREA THE REST OF THE WORK WEEK. ANOTHER
LOW PRESSURE SYSTEM EMERGING FROM THE ROCKIES SHOULD THEN MOVE
THROUGH THE GREAT LAKES ON SATURDAY WITH ITS COLD FRONT PASSING
THROUGH THE REGION LATER THAT DAY. A HIGH PRESSURE SYSTEM SHOULD
THEN START BUILDING EAST ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
THE MID-LEVEL LOW LOCATED OVER SOUTHERN DELMARVA WILL CONTINUE TO
DRIFT EASTWARD TONIGHT, WHILE THE SURFACE LOW LOCATED OFF THE NEW
JERSEY COAST WILL DRIFT EASTWARD AS WELL. RAIN CONTINUES ACROSS MOST
OF THE AREA LATE THIS AFTERNOON, AND WILL PERSIST THROUGH THE
REMAINDER OF THE EVENING. THE MID-LEVEL LOW WILL SHIFT OFF THE NEW
JERSEY COAST BY AROUND MIDNIGHT, AND CONTINUE TO MOVE FARTHER TO THE
EAST TROUGH THE NIGHT. AS THE LOWS PULL AWAY, THE LOW-LEVEL
FRONTOGENESIS AND STRONGEST LIFT WILL BEGIN TO WEAKEN ON THE WEST
SIDE OF THE SYSTEM AND MOVE TO THE NORTHEAST, WHILE DRIER AIR BEGINS
TO MOVE IN BY DAYBREAK. AS THIS HAPPENS, THE PRECIPITATION SHIELD
SHOULD BEGIN DISSIPATING OVERNIGHT AS IT CONTINUES TO SLIDE EASTWARD.
WE MAINTAIN THE WINTER WEATHER ADVISORY FOR CARBON/MONROE,
PENNSYLVANIA OVERNIGHT, AS WE EXPECT A WINTRY MIX TO BEGIN AS COLDER
AIR HAS BEGUN TO FILTER IN ON THE NORTHWEST SIDE OF THE SYSTEM. THE
QUESTION IS HOW COLD WILL IT GET, AND HOW DEEP THE BELOW FREEZING
LAYER WILL BE. THE GFS KEEPS A WARM LAYER ABOVE 925 MB THROUGH MUCH
OF THE PERIOD, WHICH WOULD INDICATE MORE FREEZING RAIN/SLEET
POTENTIAL. HOWEVER, THE NAM AND EVEN THE RUC SHOW THE POSSIBILITY OF
THE ENTIRE LAYER DROPPING BELOW FREEZING, WHICH COULD LEAD TO MORE
SNOW. THERE HAS BEEN SNOW REPORTED TO THE WEST, WHICH DOES GIVE SOME
CREDENCE TO THE POTENTIAL FOR SNOW. WE WILL GO WITH A MIXED BAG OF
PRECIPITATION OF SNOW, SLEET, FREEZING RAIN WHERE TEMPERATURES ARE
EXPECTED TO DROP BELOW FREEZING IN THE ADVISORY AREA. WE BRING RAIN,
SNOW, SLEET WHERE TEMPERATURES ARE EXPECTED TO REMAIN ABOVE FREEZING
FOR THE NEXT TIER OF COUNTIES ACROSS PORTIONS EASTERN PENNSYLVANIA
AND NORTHERN NEW JERSEY. HOWEVER, WE EXPECT ALL RAIN FROM THE PHILLY
METRO/CENTRAL NEW JERSEY AREA SOUTHWARD. SNOW/SLEET ACCUMULATIONS
ARE EXPECTED TO BE THE GREATEST ACROSS THE ADVISED AREA WHICH COULD
BE AROUND 1-2 INCHES, ALONG WITH UP TO A TENTH OF AN INCH OF
FREEZING RAIN.
A BLEND OF MAV/MET MOS, MOS GUIDE, AND ECMWF WAS USED FOR OVERNIGHT
LOWS.
WINDS WILL BE BREEZY AT TIMES TONIGHT WITH GUSTS OF 25-30 MPH.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
N MONDAY, THE MID-LEVEL AND SURFACE LOWS WILL PULL OUT TO SEA, AND
PRECIPITATION CHANCES WILL DIMINISH AFTER DAYBREAK. ALL
PRECIPITATION CHANCES ARE EXPECTED TO BE OVER WITH BY MID-LATE
MORNING. SKIES WILL CLEAR OUT THROUGH THE DAY, ALLOWING
TEMPERATURES TO WARM CLOSE TO NORMAL. MONDAY WILL CONTINUE TO BE A
BREEZY DAY, WITH GUSTS AT LEAST 25-30 MPH.
A BLEND OF MAV/MET MOS, MOS GUIDE, AND ECMWF WAS USED FOR DAYTIME
HIGHS.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
THE GFS INITIALIZATION LOOKED BETTER AT MOST LEVELS THAN THE
WRF-NMMB. WHILE THEY ARE FAIRLY CLOSE AT THE START OF THE LONG TERM,
THEY DO DEPART WITH WED`S SOLUTION WHERE WE WILL SIDE WITH THE
HEMISPHERIC MODELS. THE LONG TERM HAS A VERY WELCOME TO APRIL LOOK
TO IT WITH A STALLING FRONT AND NOT TOO MANY DRY DAYS. THE
BIGGEST CHANGE FROM YESTERDAY IS A MORE ACTIVE FRONTAL BOUNDARY
WHICH HAS ADDED WEDNESDAY TO THE WET MIXTURE.
MONDAY NIGHT LOOKS TO BE THE BEST RADIATIONAL COOLING NIGHT OF THE
WEEK AS HIGH PRESSURE PASSES ACROSS OUR CWA AND THE RIDGE AXIS IS
STILL TO OUR WEST KEEPING SKIES GENERALLY CLEAR. MIN TEMPS SIDED
TOWARD THE LOWER STAT GUIDANCE.
ON TUESDAY THE MODELS ARE PASSING A SHORT WAVE THROUGH THE RIDGING.
NET EFFECT WOULD BE SOME MID OR MORE LIKELY HIGH LEVEL CLOUDINESS
DURING THE DAY. THE APPROACHING COLD FRONT IS STILL TOO FAR WEST TO
TRIGGER ANY PCPN IN OUR CWA. THERE IS A NICE REBOUND AT 850MB WITH
TEMPS, WITH 925MB TEMPS LAGGING. POTENTIAL FOR MID 60S FROM THE FALL
LINE SEWD AWAY FROM THE COAST. GIVEN SOME CLOUDS, THE ONLY LOCATIONS
WE WENT THAT HIGH WAS INLAND WITHIN DELMARVA. LOOKS LIKE A SEA
BREEZE WILL DEVELOP SO, SOME UNCERTAINTY ABOUT IMMEDIATE COASTAL
AREA HIGH TEMPS. OVERALL WE WERE HIGHER THAN STAT GUIDANCE.
ON TUESDAY NIGHT, WHILE THERE WILL BE INSTABILITY ALOFT, MOISTURE
BELOW 700MB IS FORECAST TO BE LACKING. THE LOW CHANCE FOR SHOWERS
WAS RECONFIGURED MORE TOWARD THE WESTERN PART OF OUR CWA GIVEN THEY
WOULD HAVE THE BEST CHANCE TO HAVE PCPN REACH THEM BEFORE
DISSIPATING. MIN TEMPS, WEST ESPECIALLY, ABOVE STAT GUIDANCE
BANKING ON MORE CLOUDS EARLY.
WEDNESDAY HAS TAKEN A TURN FOR THE WETTER VS YESTERDAY`S MODEL RUNS.
WITH THE FRONT SLOWING DOWN AND HIGH PRESSURE MORE GEOGRAPHICALLY
DISPLACED, AN IMPULSE FROM THE ARKLATEX IS ABLE TO PASS ACROSS OUR
CWA POSSIBLY PRODUCING SOME SHOWERS. THERE ARE STILL GEOGRAPHICAL (N
VS S) AND SOME TIMING DIFFERENCES (WED DAY VS WED NGT), SO FOR NOW
WE WERE RATHER GENERIC IN ADDING A CHANCE OF SHOWERS.
WEDNESDAY NIGHT GOING WITH THE MAJORITY MODELING SOLUTION, WE HAVE A
RELATIVELY LULL (LOWER) CHANCE FOR SHOWERS. CHANCES THEN INCREASE
AGAIN THURSDAY AS A WARM FRONT APPROACHES OUR AREA PEAKING ON
THURSDAY NIGHT SOUTH WITH LOWER POPS ON FRIDAY. TIMING CONFIDENCE IS
LOW TO MODERATE. GIVEN THE FRONTAL BOUNDARY LOCATION MAX TEMP
CONFIDENCE IN PARTICULAR IS LESS THAN AVERAGE.
THE TIMING ON THE COLD FRONTAL INDUCED PCPN IS STILL CENTERED ON
FRIDAY NIGHT WHEN OUR POPS INCREASE AGAIN. THE MODELS ARE SHOWING
ENOUGH INSTABILITY FOR THUNDER, BUT WANT TO SEE MORE TIMING
CONTINUITY BEFORE ADDING. THE MENTION OF POPS FOR SATURDAY IS A
COMPROMISE BETWEEN THE SLOWER GFS/CAN GGEM AND ECMWF TIMING AS TO
HOW QUICKLY WILL THE FRONT MOVE OFFSHORE. THEN MAYBE SUNDAY WE CAN
FINALLY HAVE A DRY WEEKEND DAY, WELL AT LEAST WE WILL START OUR
FORECAST FOR SUNDAY THAT WAY.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
SITES VARY FROM MVFR TO IFR LATE THIS AFTERNOON. WE EXPECT EVERYONE
TO RETURN TO IFR FOR A PERIOD THIS EVENING AS PERIODS OF LIGHT TO
MODERATE RAIN, WITH BRIEF PERIODS OF HEAVY RAIN CONTINUE TO AFFECT
THE TAF SITES. AN IMPROVEMENT TO MVFR IS EXPECTED FOR THE TAF SITES
OVERNIGHT, WITH AN EVENTUAL IMPROVEMENT TO VFR MONDAY MORNING.
NORTHERLY WINDS WILL CONTINUE TO BE GUSTY THIS AFTERNOON AND BECOME
MORE NORTHWESTERLY LATER THIS EVENING AND CONTINUE INTO MONDAY.
WINDS COULD GUST 25-30 KNOTS AT TIMES TONIGHT INTO MONDAY.
OUTLOOK...
MON NIGHT THROUGH TUESDAY...VFR. HIGH CONFIDENCE.
TUESDAY NIGHT AND WEDNESDAY...MVFR POSSIBLE AT TIMES AS A SLOWLY
STALLING COLD FRONT WITH SHOWERS MOVES THROUGH THE REGION.
WEDNESDAY NIGHT THROUGH FRIDAY...A FRONTAL BOUNDARY IS FORECAST TO
STALL NEAR THE AREA WITH WAVES OF LOW PRESSURE ALONG IT. THIS WOULD
GIVE US PERIODS OF MVFR TO IFR CONDITIONS, MOST LIKELY TIMES ARE
THURSDAY NIGHT INTO FRIDAY.
&&
.MARINE...
A GALE WARNING HAS BEEN ISSUED FOR MOST OF THE ATLANTIC COASTAL
WATERS AND DELAWARE BAY STARTING AT 8 PM TONIGHT. THE ONLY ZONE LEFT
OUT OF THE GALE WARNING IS THE SANDY HOOD TO MANASQUAN ZONE AS
CONFIDENCE ON GALE FORCE GUSTS ACROSS THE NORTHERN WATERS IS LOWER.
35-40 KNOTS WINDS ARE FORECAST AROUND 2,000 FEET THROUGH THE
OVERNIGHT HOURS INTO THE MORNING HOURS MONDAY, AND ARE EXPECTED TO
CREATE GALE FORCE GUSTS. THE WINDS WILL DROP BACK BELOW GALE FORCE
MONDAY MORNING, BUT LIKELY REMAIN SMALL CRAFT ADVISORY LEVELS. SEAS
WILL REMAIN ELEVATE THROUGH AT LEAST MONDAY.
OUTLOOK...
MONDAY NIGHT...SUB SCA CONDITIONS ON DELAWARE BAY. SEAS MIGHT STILL
BE AT OR ABOVE SCA CRITERIA ON THE OCEAN. CHANCES DECREASE AS THE
NIGHT PROGRESSES.
TUESDAY THROUGH THURSDAY NIGHT...SUB SMALL CRAFT ADVISORY CONDITIONS
EXPECTED WITH A RELATIVELY WEAK PRESSURE PATTERN.
FRIDAY...THERE IS AN INCREASING CHANCE FOR SMALL CRAFT ADVISORY
CONDITIONS AS WE PROGRESS THROUGH FRIDAY AND NIGHT AS THE GRADIENT
BETWEEN AN APPROACHING FRONT AND A HIGH PRESSURE SYSTEM OVER NEW
ENGLAND TIGHTENS.
&&
.HYDROLOGY...
A FLOOD WARNING IS IN EFFECT FOR THE MILLSTONE RIVER AT BLACKWELLS
MILLS AS THAT RIVER IS EXPECTED TO CONTINUE IT/S RISE TO A FOOT OR
SO ABOVE FLOOD STAGE BEFORE CRESTING LATE TONIGHT. NEAR BANKFULL
RISES ARE EXPECTED ON LOWER PORTIONS OF THE PASSAIC RIVER OVER THE
NEXT 1 TO 2 DAYS, WITH MINOR FLOODING POSSIBLE. WE WILL CONTINUE TO
MONITOR THE SITUATION AND FLOOD WARNINGS WILL BE ISSUED IF
WARRANTED.
MOST SMALLER STREAMS IN THE AREA HAVE RESPONDED WITH MODERATE RISES
FROM THE 2 TO 3 INCHES OF RAIN THAT HAS FALLEN SINCE SATURDAY. BASED
ON OBSERVED GAGE RESPONSE, IT APPEARS THIS RAIN HAS FULLY SATISFIED
BASIN MOISTURE DEFICIENCIES SINCE EVERY AREA OF RAIN THAT NOW MOVES
OVER THE SMALL WATERSHED BASINS INDUCES AN IMPRESSIVE RESPONSE AT
THE ASSOCIATED GAGE.
AN AREA OF IMPRESSIVE RAIN IN SOUTHERN NEW JERSEY WILL BE MOVING
NORTHWEST INTO THE PHILA METRO AREA THROUGH THE EARLY EVENING HOURS.
SOME OF THIS RAIN MAY BE HEAVY ENOUGH TO CAUSE URBAN AND SMALL
STREAM FLOODING, AND ADVISORIES WILL BE ISSUED AS NECESSARY. THE
FLOOD WATCH THEREFORE REMAINS IN EFFECT THROUGH 2 AM MONDAY.
THE MAIN STEM DELAWARE RIVER, AS WELL AS THE LEHIGH AND SCHUYLKILL
RIVERS, WILL EXPERIENCE RISES OVER THE NEXT DAY OR SO IN THE 2 TO 4
FOOT RANGE, BUT CREST LEVELS ARE EXPECTED TO REMAIN UNDER
THREE-QUARTERS BANKFULL.
THE LOWER SUSQUEHANNA RIVER WILL EXPERIENCE UP TO A THREE-QUARTER
BANKFULL RISE OVER THE NEXT FEW DAYS, AND THIS RISE WILL THEN WORK
ITS WAY DOWN TO THE SHORES OF BOTH CECIL AND HARFORD COUNTIES.
RESIDENTS OF CECIL AND HARFORD COUNTY WILL SEE THIS RISE BY MID WEEK
BUT ANY FLOODING THAT MIGHT OCCUR SHOULD BE CONFINED TO THE
LOW-LYING AREAS NEAR THE RIVER.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FLOOD WATCH UNTIL 2 AM EDT MONDAY FOR PAZ054-055-060>062-070-
071-101>106.
WINTER WEATHER ADVISORY UNTIL 8 AM EDT MONDAY FOR PAZ054-055.
NJ...FLOOD WATCH UNTIL 2 AM EDT MONDAY FOR NJZ001-007>010-012-015.
DE...FLOOD WATCH UNTIL 2 AM EDT MONDAY FOR DEZ001.
MD...NONE.
MARINE...GALE WARNING FROM 8 PM THIS EVENING TO 11 AM EDT MONDAY FOR
ANZ430-431-451>455.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT MONDAY FOR ANZ450.
&&
$$
SYNOPSIS...GIGI/NIERENBERG
NEAR TERM...ROBERTSON
SHORT TERM...ROBERTSON
LONG TERM...GIGI
AVIATION...GIGI/NIERENBERG/ROBERTSON
MARINE...GIGI/NIERENBERG/ROBERTSON
HYDROLOGY...MIKETTA
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
204 PM EDT Sun Mar 30 2014
.Near Term [Through Today]...
The calming center of surface high pressure will slowly
overspread the Southeast through the night tonight. There are a
few complications regarding tonight`s minimum temperature
forecast. For one, it is somewhat unclear whether winds will go
completely calm, though they should be very light mostly
everywhere by dawn. Additionally, just about every model is
handling the upstream cirrus poorly. The HRRR has the best handle,
but doesn`t run through the night. This forecast will essentially
extrapolate the HRRR cirrus field eastward through the night. Due
to the clouds and uncertain wind forecast, have trended up with
overnight lows. Expect around 40 degrees to be common away from
the coast (near 50 along the coast), with spotty locations
reaching the upper 30s. The duration in the 30s, the clouds, and
wind forecast would all argue a very hostile environment for frost
to develop. IF frost were to occur under the current forecast
conditions it would be extremely patchy, short lived, and confined
to southeast Alabama.
.Short Term [Tonight Through Tuesday]...
An upper level ridge will be in place through this period as surface
high pressure builds east of the area. This will be a dry pattern
with no chance for rain and moderating temperatures. The lower
humidity will also allow for a rather large diurnal swing in
temperatures with chilly mornings and warm afternoons. Lows Monday
night will be in the lower to mid 40s, while Tuesday night will only
dip into the upper 40s to lower 50s. Highs will be in the upper 70s
on Monday and reach the lower to mid 80s on Tuesday.
.Long Term [Tuesday Night Through Sunday]...
The period will start out dry and warm with the upper level ridge
axis just east of the area and a surface high off the Southeast U.S.
coast ridging westward along the Gulf Coast. Highs will be in the
lower 80s for most areas on Wednesday and Thursday and mornings will
be milder than earlier in the week. The upper ridge will be shunted
eastward from Friday onward as energy over the Great Plains tries to
make eastward progress. The associated frontal system will edge
close enough to the region to tap into increasing Gulf moisture and
produce scattered showers and thunderstorms each day from Friday
through the weekend. Rain chances will be highest to the northwest
and taper off to the southeast. Temperatures will remain above
normal despite the increase in moisture.
&&
.Aviation...
[Through 18Z Monday] Breezy northwest winds will continue through
the afternoon, with a calming trend occurring through the night,
and light winds expected tomorrow. Other than a passing cirrus
deck through the night, unlimited VFR is expected.
&&
.Marine...
High pressure to the west of the waters will move east of the area
on Monday and then remain off the Southeast U.S. coast for several
days. Offshore winds and seas have dropped below headline criteria
this afternoon and this trend will continue tonight. Winds will veer
around to onshore by Monday afternoon and light generally south to
southeast winds will be the rule. A slight increase in winds speeds
and seas is expected across the Florida Panhandle waters for
Wednesday and Thursday.
&&
.Fire Weather...
Although relative humidities tomorrow will be quite low, and at time
below critical levels, fuel moisture and/or duration criteria will
not be met anywhere in the Tri-State region. Dispersions will be
lower than recent days as high pressure moves overhead, calming
winds a bit. Critical relative humidities are not anticipated
Tuesday through the end of the week.
&&
.Hydrology...
Minor flooding is forecast to begin along the Choctawhatchee River
at Caryville and Bruce early next week. Elsewhere, several other
rivers in the CWA remain in action stage, but no flooding is
forecast. The next chance for rain is on Friday.
For the latest river stages and forecasts, please visit:
water.weather.gov/ahps2/index.php?wfo=tae
&&
.Preliminary Point Temps/PoPs...
Tallahassee 39 78 41 84 47 / 0 0 0 0 0
Panama City 49 73 52 76 56 / 0 0 0 0 0
Dothan 42 77 46 81 52 / 0 0 0 0 0
Albany 39 77 45 83 50 / 0 0 0 0 0
Valdosta 40 80 43 84 48 / 0 0 0 0 0
Cross City 39 78 41 82 46 / 0 0 0 0 0
Apalachicola 48 71 49 75 54 / 0 0 0 0 0
&&
.TAE Watches/Warnings/Advisories...
FL...High Rip Current Risk until 7 PM EDT this evening for Coastal
Gulf.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM...HARRIGAN
SHORT TERM...WOOL
LONG TERM...WOOL
AVIATION...HARRIGAN
MARINE...WOOL
FIRE WEATHER...HARRIGAN
HYDROLOGY...BOLDEN
AREA FORECAST DISCUSSION
NWS GAYLORD MI
130 PM EDT SUN MAR 30 2014
.SYNOPSIS...
ISSUED AT 309 AM EDT SUN MAR 30 2014
HIGH PRESSURE WILL REMAIN IN CONTROL OF THE WEATHER THROUGH
MONDAY...BRINGING PLENTY OF SUNSHINE AND INCREASINGLY WARMER
TEMPERATURES. A FRONT CROSSING THE REGION LATE MONDAY NIGHT AND
EARLY TUESDAY WILL BRING A CHANCE FOR SOME LIGHT SHOWERS...ALONG
WITH A RETURN TO COOLER WEATHER. RAIN MAY MIX WITH...OR EVEN CHANGE
OVER...TO A BIT OF SNOW ON TUESDAY...BUT NO ACCUMULATIONS ARE
EXPECTED. COOL WEATHER WILL CONTINUE FOR THE MIDDLE AND END PORTIONS
OF THE WEEK...WITH ANOTHER CHANCE FOR A WINTRY MIX OF PRECIPITATION
THURSDAY AND FRIDAY.
&&
.UPDATE...
ISSUED AT 1125 AM EDT SUN MAR 30 2014
HIGH PRESSURE SURFACE AND ALOFT WILL ENSURE A NICE AFTERNOON FOR
NORTHERN MICHIGAN WITH JUST A FEW CLOUDS DRIFTING BY. WIDESPREAD
HIGHS IN THE 40S EXPECTED.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 309 AM EDT SUN MAR 30 2014
HIGH IMPACT WEATHER POTENTIAL: NONE.
PATTERN SUMMARY: AN EARLY MORNING LOOK AT THE PATTERN ACROSS THE
CONUS REVEALS AN ACTIVE SETUP...WITH LOW PRESSURE SYSTEMS ALONG BOTH
COASTS...AND A NARROW RIDGE OF HIGH PRESSURE IN BETWEEN THESE
SYSTEMS... ARCHING FROM QUEBEC...THROUGH THE GREAT LAKES AND DOWN
THE MISSISSIPPI VALLEY. THIS RIDGE AXIS CURRENTLY LIES JUST WEST OF
THE FORECAST AREA...WITH A RIBBON OF CLEARING ALLOWING LOW
TEMPERATURES TO FALL RAPIDLY AS BOUNDARY LAYER WINDS DECOUPLE.
LOOKING FORWARD THROUGH THE SHORT TERM FORECASTS REQUIRES US TO LOOK
UPSTREAM...AND...SOMEWHAT DIFFERENTLY THAN WE HAVE SEEN OF
LATE...MUCH OF WHAT IS UPSTREAM IS DOMINATED BY PACIFIC...MARITIME
POLAR AIR...WITH ANY ARCTIC AIR NOW BOTTLED UP NORTH OF THE REGION.
THIS PACIFIC FLOW WILL RESULT IN LEE-SIDE CYCLOGENESIS EAST OF THE
ROCKIES DURING THE DAY TODAY...WITH THIS LOW PRESSURE DEEPENING AND
BEGINNING TO DEPART TO THE NORTH AND EAST BY THE END OF THIS PERIOD
AROUND DAYBREAK MONDAY. THE DOWNSTREAM LONGWAVE TROUGH IS MUCH
SLOWER MOVING...AND THE DEVELOPING SQUEEZE PLAY IN BETWEEN THESE
FEATURES WILL FORCE HEIGHTS TO BUILD OVER THE GREAT LAKES WITH QUIET
AND MODERATING CONDITIONS EXPECTED FOR NORTHERN MICHIGAN. CERTAINLY
A WELCOME REPRIEVE FROM AN EXCEPTIONALLY COLD MONTH OF MARCH.
THROUGH DAYBREAK: TEMPERATURES WILL CONTINUE TO TUMBLE THROUGH THE
TEENS GIVEN CLEAR SKIES AND CALM-LIGHT WINDS. ALSO CAN/T RULE OUT
SOME PATCHY GROUND FOG GIVEN IMPRESSIVE OVERNIGHT COOLDOWN.
TODAY: RIDGE AXIS WILL BE PRETTY MUCH OVERHEAD TO START THE
DAY...GRADUALLY SHIFTING EAST TO A POSITION OVER LAKE HURON
TOWARDS EVENING. THERE/S A RELATIVE LACK OF MOISTURE THROUGH THE
COLUMN TO START THE DAY WITH PWATS SUB 0.25" /A LITTLE BELOW
SEASONAL NORMS FOR LATE MARCH/ WITH VALUES INCREASING DURING THE DAY
AS A CHUNK OF PACIFIC MOISTURE /SEEN NOW AS A PLUME OF DEEP MOISTURE
ACROSS THE NORTHWESTERN QUARTER OF THE COUNTRY/ RIDES EAST. WHILE
THIS COULD MANIFEST ITSELF AS SOME HIGH CLOUDS FOR THE NORTHERN HALF
OF THE CWA /ESP FOR THE SECOND HALF OF THE DAY/...THE LACK OF LLEVEL
MOISTENING BENEATH BUILDING MID LEVEL HEIGHTS SUGGESTS NO REAL
POTENTIAL FOR CU DEVELOPMENT. THUS...EXPECT ABUNDANT SUNSHINE FOR
THE AREA WITH NO SENSIBLE WEATHER CONCERNS.
TEMPERATURES /CONFIDENCE: HIGH/:
TRAJECTORY ANALYSIS PLACES THIS AFTERNOON/S AIRMASS OVER SOUTHERN
MINNESOTA 24 HOURS PREVIOUS WITH T9S SURGING TO 0-3C BY LATE
AFTERNOON UNDER STRONG WARM ADVECTION. WITH BUILDING HEIGHTS AND
NEARBY RIDGE AXIS...MIXING ISN/T GOING TO BE TOO STRONG. LOOKING
BACK TO MINNESOTA...AREAS THAT WERE UNABLE TO MIX DEEPLY REACHED THE
LOWER 40S...WITH UPPER 40S FURTHER WEST WHERE MECHANICAL MIXING
COMBINED WITH WARMER TEMPS ALOFT TO BOOST SURFACE TEMPS. EXPECT
THAT WE/LL BE CLOSER TO THE FORMER TODAY...AND EXPECT HIGHS IN THE
40-45 DEGREE RANGE. AMAZINGLY...THAT WILL PUT US JUST ABOUT WHERE
WE SHOULD BE FOR THE END OF MARCH.
AS MENTIONED BY THE PREVIOUS DAYSHIFT...LIGHT FLOW REGIME AND
SOMEWHAT WARMER TEMPERATURES SHOULD ALLOW FOR SOME LAKE BREEZE
DEVELOPMENT...KEEPING HIGHS LOCALLY COOLER ALONG THE LAKE HURON
COAST.
TONIGHT: RIDGE CONTINUES TO PUSH EAST OF THE GREAT LAKES
REGION...WITH NORTHERN STREAM COLD FRONT STALLING NEAR LAKE SUPERIOR
AS LOW PRESSURE ALONG THE EAST SLOPES OF THE ROCKIES BEGINS TO
DEPART AND HEAD NORTHEAST. MOISTURE CONTINUES TO SLOWLY
INCREASE...BUT PRIMARILY AT UPPER LEVELS WITH TOP-DOWN SATURATION
LIKELY ONLY YIELDING AN INCREASE IN UPPER LEVEL CLOUDS THROUGH THE
OVERNIGHT. GRADIENT STRENGTHENS THROUGH THE NIGHT...WITH MOST
LOCATIONS RE-COUPLING DURING THE OVERNIGHT. SEE NO REPEAT OF ANY
FOG GIVEN BETTER LLEVEL MIXING AND CONTINUED DRY LLEVEL CONDITIONS.
TEMPERATURES /CONFIDENCE: MODERATE-HIGH/:
TEMPERATURES WILL BE A LITTLE COMPLEX WITH EVENING MCLEAR SKIES AND
DECOUPLING LIKELY TO GIVE WAY TO INCREASED MIXING AS THE NIGHT GOES
ON. THIS WILL YIELD LOWS COLDEST OVER NORTHEAST LOWER WITH LOWS
LIKELY TO DIP TO AROUND 20 /AND PERHAPS A TAD BELOW THIS/...WITH
TEMPS OVER NORTHWEST LOWER STRUGGLING TO FALL MUCH BELOW THE
FREEZING MARK.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 309 AM EDT SUN MAR 30 2014
...REAL SPRING "WARMTH" GIVES WAY TO BELOW NORMAL TEMPERATURES (GO
FIGURE)...
HIGH IMPACT WEATHER POTENTIAL: WATCHING WINTRY PRECIP THREAT LATER
IN THE WEEK.
OVERVIEW: PATTERN REMAINS AN AGITATED ONE...WITH EXTENDED AMPED
PACIFIC REGIME OVER THE CONUS TUCKED NICELY ON SOUTH SIDE OF WELL
DEVELOPED NORTH CANADA COLD CORE GYRE. PACIFIC PATTERN CONTINUES TO
WIN OUT OVER NORTHERN MICHIGAN...WITH STEADY RETREAT OF OVERHEAD
COLD AIRMASS AS AGGRESSIVE UPSTREAM WARMING BEGINS. 00Z RAOB/HIGH
RES RAP GUIDANCE CONFIRMS SUCH...SHOWING H8 TEMPERATURES SPIKING
INTO THE TEENS (THAT`S ABOVE ZERO FOLKS!) ACROSS THE HIGH
PLAINS...WITH ABOVE ZERO H8 AIR ALREADY ADVANCING TO THE MISSISSIPPI
RIVER. EXPECTED RATHER SUBSTANTIAL UPPER MISSISSIPPI VALLEY LOW
PRESSURE DEVELOPMENT EARLY THIS WORK WEEK WILL ONLY HELP THE
NORTHERN LAKES WARMING CAUSE...WITH MUCH OF THE AREA TO FALL
SQUARELY IN THE WARM SECTOR OF THIS SYSTEM AS IT TRACKS TO OUR
NORTHWEST. UNFORTUNATELY...COOL AIR WILL BE FORCED SOUTH ON ITS
BACKSIDE...ONCE AGAIN DROPPING TEMPERATURES TO BELOW NORMAL LEVELS
AS WE HEAD THROUGH THE MID AND AND PORTIONS OF NEXT WEEK. PACIFIC
WAVE TRAIN REMAINS...AT LEAST SETTING UP SOME POTENTIAL FOR BOUTS OF
MORE WINTRY WEATHER HEADING INTO THURSDAY AND FRIDAY. OH...THE
JOY!
PRIMARY FORECAST CONCERNS/CHALLENGES: PLENTY! TEMPERATURE TRENDS
THROUGHOUT...PRECIP TIMING/AND EVENTUAL TYPE...HEADING THROUGH NEXT
WORK WEEK.
DETAILS: JUST HOW WARM TO GO ON MONDAY? ABOUT TEXTBOOK END OF
MARCH/BEGINNING OF APRIL SPRING STORM WILL BE UNDERGOING FULL
DEVELOPMENT ACROSS THE CENTRAL PLAINS EARLY MONDAY...EXPECTED TO
PASS SOMEWHERE VICINITY CENTRAL/WESTERN UPPER MICHIGAN TUESDAY.
STRONG DOWNSTREAM OFF THE DECK WAA EXPECTED...WITH NOW MULTI-DAY
PROGS SUPPORTING H8 READINGS SPIKING TO NEAR 10C BY LATER MONDAY
OVER NORTHERN MICHIGAN. WITH ELEVATED WARM FRONT ALREADY NORTH OF
THE AREA...AND CORE OF MID LEVEL DYNAMICS WELL OFF TO OUR
WEST...WOULD EXPECT PLENTY OF SUNSHINE TO FURTHER KICK THE WARMING
INTO OVERDRIVE. INCREASINGLY DEEP MIXED LAYER/FORCED MECHANICAL
MIXING PER INCREASING WINDS SHOULD ALLOW SURFACE TEMPERATURES TO
RESPOND ACCORDINGLY...AND REALLY LIKE INHERITED HIGHS WILL INTO THE
50S/NEAR 60 OVER NORTHERN LOWER MICHIGAN. SOUTHEAST LOW LEVEL FLOW
WILL KEEP NORTHEAST LOWER AND EASTERN UPPER MICHIGAN SEVERAL DEGREES
COOLER. MILD AIR CONTINUES INTO MONDAY NIGHT AS SOUTH FLOW
REMAINS...AND FEEL SOME AREAS MAY FAIL TO FALL OUT OF THE 40S. DRY
WEATHER GIVES WAY TO INCREASING SHOWER CHANCES MONDAY NIGHT AS
OCCLUDED FRONT INTERACTS WITH NARROW BAND OF ENHANCED DEEP LAYER
MOISTURE. STRONGEST AND DEEPEST DYNAMICS REMAIN TO OUR
NORTHWEST...WHERE HEAVIEST AND STEADIEST PRECIPITATION SHALL RESIDE.
BACK TO 2014 SPRING NORMALCY QUICKLY ON TUESDAY AS SURGE OF COLDER
AIR FOLLOWS PASSAGE OF OCCLUDED FRONT. MORNING HIGH TEMPERATURES IN
THE 30S AND 40S WILL SLOWLY FALL THROUGH THE AFTERNOON ON GUSTY
SOUTHWEST TO WEST WINDS. LIGHT RAIN/SNOW SHOWERS TRANSITION TO
MAINLY SNOW AS COLD AIR DEEPENS AND SYSTEM BACKSIDE MOISTURE
REMAINS. JUST MINIMAL...IF ANY...ACCUMULATION IS EXPECTED.
UNCERTAINTY THE NAME OF THE GAME HEADING INTO THE MID AND END
PORTIONS OF THE WEEK. QUESTIONS ARE MANY CONCERNING NEXT WAVE
EXPECTED TO EJECT OUT OF THE INTERMOUNTAIN WEST. INTERACTION BETWEEN
SOUTHERN CANADA HIGH/ASSOCIATED DRY AIR FEED AND WHAT SHOULD BE
RATHER VIGOROUS MID LEVEL WAVE LEADING TO RATHER SIGNIFICANT
DISCREPANCIES AMONGST MID RANGE GUIDANCE. ECMWF REMAINS MOST
ROCK-STEADY...SUGGESTING A MORE AMPED AND FURTHER NORTH SOLUTION
WITH LOW PRESSURE MOVING DIRECTLY ACROSS THE GREAT LAKES TO END THE
WORK WEEK. OTHER GUIDANCE STARTING TO FALL IN LINE WITH THIS MORE
NORTH/AMPED SOLUTION...ALTHOUGH HONESTLY...THIS DOES LITTLE TO
INCREASE CONFIDENCE AS A MORE SOUTH DISPLACED SYSTEM IS FULLY
PLAUSIBLE GIVEN EXPECTED SET-UP AND POTENTIAL FOR A STRONGER
CANADIAN HIGH. TEMPERATURE PROFILE REMAINS MARGINALLY SUPPORTIVE OF
A MIXED PRECIP EVENT IF FURTHER NORTH SOLUTIONS VERIFY. SET-UP ALSO
HAS SOME INTRIGUING FREEZING RAIN POSSIBILITIES...WITH POTENTIAL FOR
MAINTENANCE OF DRY AND COLD EAST FLOW TO MAINTAIN SUB-FREEZING
SURFACE TEMPERATURES...ALL THE WHILE ELEVATED WARM NOSE DEEPENS. OF
COURSE...MUCH TOO FAR OUT TO SHOW SUCH SPECIFICS...ESPECIALLY
CONSIDERING UNCERTAINTY IF SYSTEM WILL EVEN DIRECTLY AFFECT OUR
AREA. LITTLE CHOICE BUT TO RUN WITH A GENERIC RAIN/SNOW CHANCE
WORDING FOR NOW...WITH PLENTY OF TIME TO FINE-TUNE DETAILS IN
COMING DAYS. WHILE EXCEPTIONALLY COLD AIR NOW LOOKS LIKE A THING OF
THE PAST...OVERALL TRENDS FAVOR BELOW NORMAL TEMPERATURES WEDNESDAY
THROUGH NEXT WEEKEND...WITH HIGHS MOSTLY IN THE 30S AND LOWER
40S/OVERNIGHT LOWS IN THE 20S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 130 PM EDT SUN MAR 30 2014
VFR CONDITIONS EXPECTED THROUGH MONDAY MORNING WITH MID AND HIGH
LEVEL CLOUDINESS EXPECTED.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...JPB
SYNOPSIS...MSB
SHORT TERM...ARNOTT
LONG TERM...MSB
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1237 PM CDT SUN MAR 30 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 359 AM CDT SUN MAR 30 2014
ANOTHER WARM DRY SURGE OF AIR MOVES OFF THE CNTL ROCKIES TODAY. THE
TEMPERATURE FORECAST FOLLOWS THE UPPER MIDDLE OF THE 13 MODEL SUPER
ENSEMBLE FOR HIGHS IN THE 70S TO NEAR 80. A STATIONARY FRONT IS
EXPECTED TO DEVELOP ALONG THE SD BORDER CAUSING WINDS TO BACK ACROSS
THE NORTH KEEPING HIGHS NEAR 70. WE ALSO SEE A FAIRLY SOLID CIRRUS
SHIELD DEVELOPING OFF THE LARAMIE AND FRONT RANGE LIMITING HEATING
SOMEWHAT. SOUTH WINDS INCREASE TO 10 TO 20 MPH WITH GUSTS TO 25 MPH
ACROSS MOST OF THE FCST AREA.
FOR TONIGHT...SFC LOW PRESSURE WILL TRACK THROUGH THE CENTER OF THE
FCST AREA AND WINDS BECOME NORTHWEST BEHIND THE SFC LOW ACROSS WRN
NEB. ISOLATED THUNDERSTORMS ARE POSSIBLE THIS EVENING AND OVERNIGHT
IN RESPONSE TO A LOW LEVEL JET AND COOLING/FALLING HEIGHTS ALOFT.
THE NEW MODEL CONSENSUS BRINGS A SHARP 500 MB TROF INTO ERN WY AT
06Z WHICH CLOSES OFF ACROSS NW NEB BY 12Z. THERE ARE SIGNS OF THE
HEIGHTS BACKING IN ALOFT ACROSS WRN SD AT THIS TIME WHICH IS
TROUBLING SINCE THE LATEST ENSEMBLE SOLN IS TAKING THE UPPER LEVEL
ENERGY ACROSS THE TETONS AND BIG HORN RANGES BUT THEN IT DROPPING
SOUTH OF THE BLACK HILLS. THIS MORE SRN TRACK RAISES THE POP ACROSS
NWRN NEB BETWEEN 06Z AND 12Z. THE NAM AND GEM REGIONAL THEN BRING
THE RAIN SNOW LINE INTO NRN SHERIDAN COUNTY BETWEEN 09Z AND 12Z.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 359 AM CDT SUN MAR 30 2014
ATTENTION IN THE EXTENDED PERIODS CENTER ON PRECIPITATION
CHANCES...MAINLY THE POTENTIAL OF TWO SIGNIFICANT LATE WINTER TYPE
STORMS THAT MAY BRING ACCUMULATING SNOW TO PORTIONS OF THE CWA.
THE FIRST SYSTEM WILL BE ONGOING ACROSS OUR NORTHERN ZONES BY 12Z
MONDAY. LOW PRESSURE AND ASSOCIATED PV ANOMALY WILL CROSS FROM THE
CENTRAL ROCKIES NORTHEAST OUT ONTO PLAINS...DRAGGING MODIFIED
ARCTIC AIR SOUTH FROM CANADA ACROSS THE NORTHERN/CENTRAL PLAINS.
MEDIUM RANGE MODELS HAVE GENERALLY COME INTO FAIR AGREEMENT WITH
THE TRACK OF THE SURFACE CYCLONE...BUT INTENSITY/TIMING
DIFFERENCES STILL EXIST. ATTM GENERALLY FAVOR THE GEM SOLUTION IN
WHICH THE TRACK FAVORS STRONG FRONTOGENETIC FORCING MAINLY NORTH
OF THE CWA. THAT BEING SAID...THERE/S STILL STRONG AGREEMENT THAT
SNOW WILL WRAP AROUND THE LOW BACK ACROSS NORTHERN PORTIONS OF THE
CWA. ATTM SNOW ACCUMULATIONS LOOK FAVORABLE FOR NORTHWESTERN
NEBRASKA EARLY MONDAY...THEN TRANSITION EAST THROUGH THE DAY. THE
PTYPE FORECAST IS STILL PROBLEMATIC. THE GEM SOLUTION IS WARMER
WITHIN THE WARM SECTOR AS THE MODEL LIFTS THE LOW FURTHER NORTH
THAN EAST...CHANGEOVER TO ALL SNOW MAY NOT OCCUR FOR OUR FAR
EASTERN ZONES UNTIL MID-LATE AFTERNOON. WHERE THE CHANGE OVER DOES
OCCUR EARLY...IMPACTS TO TRAVEL WOULD BE EXPECTED...ESPECIALLY
GIVEN WIND GUSTS IN EXCESS 45 MPH. ATTM ALONG AND NORTH OF HIGHWAY
20 IN CHERRY AND SHERIDAN COUNTIES IS WHERE THE GREATEST
CONFIDENCE IN SEEING THE EARLY CHANGEOVER AND ACCUMULATING SNOW.
FOR THIS...WILL ISSUE A WINTER WEATHER ADVISORY WITH THIS FORECAST
PACKAGE FOR THE TWO COUNTIES LISTED AS IMPACTS TO
KVTN...RANCHING...HIGHWAY 20 AND THE POPULOUS CENTERED ALONG THE
HIGHWAY ARE ANTICIPATED TO BE SIGNIFICANT. NOTE...IT COULD VERY
WELL BE THAT SOUTHERN PORTIONS OF THESE TWO COUNTIES NOT SEE MUCH
IF ANY ACCUMULATING SNOW WITH THIS SYSTEM WHILE THE FAR NORTH
EXPERIENCES NEAR BLIZZARD CONDITIONS AND UP TO 4 INCHES OF SNOW. A
HIGH END WIND ADVISORY IS ANTICIPATED MONDAY AS WELL ACROSS THE
ENTIRE CWA. A STACKED PRESSURE GRADIENT WITH PRESSURE RISES ON THE
ORDER OF UP TO 3 MB PER HOUR WILL LEAD TO NEAR HIGH WIND WARNING
GUST CRITERIA. WILL LET THE DAY SHIFT FINE TUNE THE SPECIFICS.
LASTLY...NEGATIVE LI/S ACROSS NORTH CENTRAL/NORTHERN NEBRASKA
EARLY MONDAY WITH WEAK INSTABILITY ALOFT MAY YIELD A FEW EMBEDDED
CONVECTIVE SHOWERS...WHETHER SNOW OR RAIN. NO MENTION OF THUNDER
WAS INCLUDED BEYOND 12Z MONDAY...BUT MAY NEED TO BE LOOKED AT
FURTHER.
LOW AMPLITUDE TRANSITORY RIDGING BUILDS ATOP THE PLAINS ON TUESDAY
WITH A RETURN TO AN ACTIVE PATTERN BY MIDWEEK. SOUTHWESTERLY FLOW IN
THE UPPER LEVELS WILL PREVAIL AS THE NEXT LONGWAVE TROUGH OF
INTEREST STARTS TO BUILD ACROSS THE DESERT SOUTHWEST WEDNESDAY.
SLIGHT OPPORTUNITIES FOR QPF ALSO ARRIVE ON WEDNESDAY WITH THE
APPROACH OF FAVORABLE UPPER LEVEL JET SUPPORT AND A SW DISTURBANCE.
HOWEVER BETTER CHANCES ARRIVE LATE IN THE WEEK AS THE TROUGH EJECTS
NORTHEAST FROM THE 4 CORNERS ONTO THE CENTRAL PLAINS. THERE REMAINS
LARGE DISCREPANCIES ON HOW THE MODELS HANDLE THIS SYSTEM...WITH THE
ECMWF NOW TAKING ON A NEGATIVE TILT AND A FAVORABLE TRACK OF THE H5
LOW FOR SNOW ACCUMULATION...POSSIBLY SIGNIFICANT ACROSS THE WEST CENTRAL
SANDHILLS. THE GFS REMAINS OPEN AND PROGRESSIVE WITH FAR LESS
IMPACTS. DUE TO THE MYRIAD OF WEATHER CURRENTLY GOING ON RIGHT
NOW...FELT IT WAS BEST TO NOT VARY FROM A GENERAL MODEL BLEND WITH
THIS LATE WEEK SYSTEM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1237 PM CDT SUN MAR 30 2014
HIGH CLOUDINESS /VFR CONDITIONS/ WILL STICK AROUND TODAY ACROSS
ALL OF WESTERN NEBRASKA. ALTHOUGH A FEW ISOLATED THUNDERSTORMS ARE
POSSIBLE THIS EVENING...MAINLY ACROSS FAR WESTERN NEBRASKA...THE
MAIN THREATS WILL ARRIVE LATE TONIGHT IN THE FORMS OF WINTRY
PRECIPITATION AND WIND. A STRONG COLD FRONT WILL SWITCH THE WINDS
TO NORTHWEST AND INCREASE DRASTICALLY WITH GUSTS TO AT LEAST 30
KTS BY DAYBREAK. A RAIN/SNOW MIX IS LIKELY ACROSS NORTHERN
NEBRASKA...INCLUDING KVTN...AFTER 31/09Z WITH A CHANGE TO ALL SNOW
BY 31/14Z. DUE TO THE STRONG WINDS...ANY SNOW WILL EASILY REDUCE
VISIBILITY TO IFR. FARTHER SOUTH...INCLUDING KLBF...THE CHANCE OF
PRECIPITATION IS MUCH LOWER BUT THE WINDS WILL BE AS STRONG.
&&
.FIRE WEATHER...
ISSUED AT 359 AM CDT SUN MAR 30 2014
RED FLAG CONDITIONS ARE EXPECTED ACROSS THE ERN PANHANDLE...CENTRAL
SANDHILLS...FRENCHMAN BASIN AND THE LOESS PLAINS. THE FORECAST IS A
LOW END RED FLAG WARNING AS THE RAP SHOWS WINDS AT 700MB WEAKENING
THIS AFTERNOON WHILE THE NAM ACTUALLY STRENGTHENS THEM. THE FORECAST
FOLLOWS A BLEND OF THE GUIDANCE FROM THE RAP13...HRRR...NAMDNG AND
AVN MOS MODELS FOR SOUTH WINDS OF 10 TO 20 MPH AND GUSTS TO 25 MPH.
DEWPOINTS SHOULD FALL INTO THE TEENS...BUT ABOUT 5 DEGREES F HIGHER
THAN SATURDAY.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 9 PM CDT /8 PM MDT/ THIS EVENING FOR
NEZ204-206-210-219.
WINTER WEATHER ADVISORY FROM 4 AM CDT /3 AM MDT/ TO 7 PM CDT /6
PM MDT/ MONDAY FOR NEZ004-005-094.
&&
$$
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...DS
FIRE WEATHER...CDC
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
326 PM CDT SUN MAR 30 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 325 PM CDT SUN MAR 30 2014
MAIN FORECAST CHALLENGE WILL BE THE STORM SYSTEM FOR LATER TONIGHT
INTO EARLY TUESDAY. 12Z MODELS ARE IN MUCH BETTER AGREEMENT
OVERALL WITH THIS SYSTEM WHICH INCREASES CONFIDENCE FOR THE
WARNING PHASE. AS OF MID TO LATE AFTERNOON TEMPS HAD CLIMBED INTO
THE MID TO UPPER 50S ACROSS THE SOUTHWEST FA BUT HAVE MAINTAINED
THE MID 30S IN THE NORTHWEST. WINDS HAVE PRETTY MUCH SHIFTED TO A
NORTHERLY DIRECTION NOW ACROSS ALL BUT THE FAR EASTERN FA. ALSO
SEEING SFC DEW POINTS IN THE MID 30S ACROSS THE SOUTHERN FA WITH
SOME 40S IN SOUTHWEST MN. SEEING CLOUD COVER THICKENING A BIT
ACROSS THE AREA BUT STILL SOMEWHAT THIN ALLOWING SOME SUN THRU.
THIS IS THE CALM BEFORE THE STORM. THICKER CLOUDS AND MORE
SUBSTANTIAL ECHOES ARE SHOWING UP OVER EASTERN MT/WESTERN ND NOW.
MODELS SLOWLY BRING SOME OF THIS NORTHEAST INTO MAINLY THE KDVL
REGION LATER THIS EVENING. TEMPS WILL STAY MILD THIS EVENING
AND EVEN AFTER MIDNIGHT...ESPECIALLY IN THE SOUTHERN AND EASTERN
FA. THEREFORE AS THIS BAND OF PCPN EXPANDS ESPECIALLY AFTER
MIDNIGHT PCPN TYPE COULD BECOME MORE OF AN ISSUE. THEREFORE
THINKING SOME FORM OF MIXED PCPN MAY FALL LATE THIS EVENING INTO
THE OVERNIGHT HOURS MAINLY ACROSS THE SOUTHERN AND EASTERN FA
WHERE TEMPS ARE A LITTLE MILDER. NOT THINKING THIS WILL BE THE
MAIN FORECAST ISSUE THOUGH...BUT WOULD DEFINITELY ADD TO THE
PROBLEMS ASSOCIATED WITH THIS SYSTEM.
THINKING THE SNOW WILL BEGIN TO GET HEAVIER AFTER MIDNIGHT ACROSS
THE KDVL REGION INTO THE NORTHERN RED RIVER VALLEY. NORTHEAST
WINDS WILL ALSO BEGIN TO CRANK UP BETWEEN 06Z AND 12Z FOR THIS
AREA SO WILL GO AHEAD AND ISSUE A BLIZZARD WARNING FOR THIS AREA
REPLACING THE BLIZZARD WATCH. AS THE SNOW BAND MOVES INTO
NORTHWEST MN EAST OF THE VALLEY WINDS SHOULD NOT BE AS BIG OF A
PROBLEM. WILL ISSUE A WINTER STORM WARNING FOR THIS AREA. MAIN
QUESTION WILL CONTINUE TO BE WARM TEMPS ACROSS SOUTHEAST ND INTO
WEST CENTRAL MN. THIS WILL AFFECT SNOW TOTALS AND EXACTLY WHEN
BLIZZARD CONDITIONS MAY GET UNDER WAY. THINK THERE IS STILL ENOUGH
UNCERTAINTY FOR THIS AREA TO KEEP THE BLIZZARD WATCH GOING THERE.
FOR THE FARGO MOORHEAD AREA CONDITIONS WILL PROBABLY DETERIORATE
ON MONDAY MORNING. THEREFORE WENT WITH A BLIZZARD WARNING FOR THAT
AREA STARTING AT 12Z MONDAY. THIS IS THE TYPE OF SYSTEM THOUGH
THAT THERE COULD INITIALLY BE LARGE VARIATIONS IN CONDITIONS FROM
ONE PORTION OF A COUNTY TO ANOTHER. BIGGEST QUESTION MARK IS WHAT
TO DO WITH EASTERN OTTER TAIL AND WADENA COUNTIES. AFTER
COORDINATING WITH ADJACENT OFFICES WENT WITH A WINTER WEATHER
ADVISORY. AS FAR AS SNOW TOTALS THIS IS DEFINITELY A CHALLENGE.
REALLY THIS IS FORECASTING A RECORD TYPE EVENT SO HARD TO USE MUCH
PERSONAL EXPERIENCE. WENT WITH A BAND OF 20 OR SO INCHES FROM
COOPERSTOWN TO KGFK TO THE LAKE OF THE WOODS. MOST UNCERTAINTY
MAY BE ACROSS SOUTHEAST ND AND WEST CENTRAL MN. WITH MODELS
TRENDING NORTHWARD THE PAST FEW RUNS AND SLIGHT SHIFT COULD MAKE A
BIG DIFFERENCE. LEFT THE EXPIRATION TIME AT 12Z TUE ALTHOUGH THERE
COULD STILL BE SOMETHING LEFT IN THE EASTERN FA.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 325 PM CDT SUN MAR 30 2014
LEFT THE TUE AFTERNOON INTO WED TIME FRAME DRY. TEMPS WILL DEPEND
ON SNOW AMOUNTS FROM THE MON/TUE STORM.
WEDNESDAY NIGHT-SUNDAY...12Z MODELS ALL INDICATE A STRONG SYSTEM
WILL PROPAGATE ACROSS THE CENTRAL CONUS AROUND FRIDAY. HOWEVER...THE
MODELS DIFFER WITH EXACTLY HOW FAR NORTH THIS SYSTEM WILL TRACK. THE
GEM AND ECMWF BRING HEAVY SNOW AND STRONG WINDS INTO AT LEAST THE
SOUTHERN FA...WHILE THE GFS KEEPS ALL SENSIBLE WEATHER TO THE SOUTH.
KEPT THE IDEA OF LOWER POPS ACROSS THE SOUTHERN FA FOR THIS SYSTEM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1244 PM CDT SUN MAR 30 2014
MVFR CIGS ARE DROPPING SOUTH ACROSS NORTHEAST NORTH DAKOTA BEHIND
THE WEAK COLD FRONT THAT HAS SHIFTED WINDS FROM THE NORTH.
ANTICIPATE THAT THESE LOWER CIGS WILL EVENTUALLY INVADE ALL TAF
SITES...BUT NOT SURE EXACTLY WHEN. FOLLOWED THE LATEST RAP GUIDANCE
FOR TIMING. CONDITIONS WILL QUICKLY DETERIORATE TO IFR/LIFR
CONDITIONS MONDAY MORNING AS HEAVY SNOW AND STRONG WINDS BECOME
POSSIBLE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...BLIZZARD WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY MORNING FOR
NDZ052-053.
BLIZZARD WARNING FROM 1 AM MONDAY TO 7 AM CDT TUESDAY FOR
NDZ006>008-014>016-024-026>030-038-054.
BLIZZARD WARNING FROM 7 AM MONDAY TO 7 AM CDT TUESDAY FOR NDZ039-
049.
MN...BLIZZARD WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY MORNING FOR
MNZ029.
WINTER STORM WARNING FROM 7 AM MONDAY TO 7 AM CDT TUESDAY FOR
MNZ015>017-022>024-027-028.
BLIZZARD WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING FOR
MNZ030-040.
BLIZZARD WARNING FROM 1 AM MONDAY TO 7 AM CDT TUESDAY FOR MNZ001-
004-007.
WINTER STORM WARNING FROM 1 AM MONDAY TO 7 AM CDT TUESDAY FOR
MNZ005-006-008-009-013-014.
BLIZZARD WARNING FROM 7 AM MONDAY TO 7 AM CDT TUESDAY FOR MNZ002-
003.
WINTER WEATHER ADVISORY FROM 7 PM MONDAY TO 7 AM CDT TUESDAY FOR
MNZ031-032.
&&
$$
SHORT TERM...GODON
LONG TERM...GODON/TG
AVIATION...TG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1244 PM CDT SUN MAR 30 2014
.UPDATE...
ISSUED AT 1244 PM CDT SUN MAR 30 2014
TEMPS HAVE JUMPED ABOVE FORECAST HIGHS IN A FEW SPOTS SO WILL
INCREASE MAX TEMPS A BIT MORE FOR TODAY. NO OTHER CHANGES PLANNED
FOR THIS UPDATE.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 410 AM CDT SUN MAR 30 2014
BOY...COMPLEX SYSTEM. MUCH CHAT WITH NEIGHBORING OFFICES AND WPC
SNOW DESK. CONSENSUS FROM NATIONAL FOLKS AFTER SEEING 00Z EURO WAS
TO GO WITH A GEM/EURO BLEND AND A FARTHER NORTHWEST TRACK OF HEAVY
SNOW AXIS. ALL MODELS HAVE BEEN SHIFTING NORTHWEST WITH HVY SNOW
AXIS PAST 24 HOUS AND 00Z RUNS OF GFS/NAM 06Z NAM THE SAME. ALSO A
BIT SLOWER. THIS CREATES ISSUES WITH CURRENT WATCH HEADLINES
ISSUED SATURDAY.
FOR TODAY...LIGHT RAIN NORTHEAST OF GRAND FORKS WILL MOVE
NORTHEAST OUT BY 12Z...COLD FRONT WILL DROP INTO NRN ND BY 12Z AND
MOVE SOUTH. COLDER AIR WITH IT NOT TOO DRASTIC UNTIL A BIT LATER
TODAY. SOUTHEASTERN ND WILL BE IN WARMER AIR AND WITH SOME SUN
TODAY COULD BOOST WELL INTO THE 50S WHERE NRN ND STAYS IN THE
MID 30S OR FALLS. WATER VAPOR SHOWS POWERFUL 500 MB SHORTWAVE
MOVING INTO CENTRAL CALIFORNIA WITH LIGHTNING STRIKES NOTED
EARLIER NR SAN FRANCISCO. SYSTEM WILL MOVE EAST AND SURFACE LOW
WILL DEVELOP AND MOVE INTO NORTHERN NEBRASKA WITH UPPER WAVE IN
WRN NEBRASKA/WYOMING 12Z MON. A STREAK OF PRECIPITATION WILL
SPREAD EAST-NORTHEAST INTO CENTRAL-NORTHEASTERN ND TONIGHT IN THE
FROM OF SNOW. LOW PRESSURE WILL DEEPEN AND TRACK NORTH-NORTHEAST
TO NEAR SIOUX FALLS 18Z MON AND 500 MB LOW DEEPENS AS WELL IN THE
CNTRL DAKOTAS...AND BY 00Z TUES SFC LOW NR WILMAR MN WITH UPPER
LOW NORTHEASTERN SD. STRONG ISENTROPIC LIFT AND PLENTIFUL MOISTURE
WILL ALLOW A DEF ZONE BAND OF SNOW TO FORM RAPIDLY MONDAY MORNING
IN FAR NW MN INTO DVL REGION INTO SOUTHWESTERN ND AND THEN PIVOT
SLOWLY SOUTH AND EAST THRU THE DAY. ALL MODELS KEEP FAR
SOUTHEASTERN FCST IN WARMER AIR ALOFT....WITH GEM/EURO WARMEST
KEEPING ANY PRECIP THERE IN FERGUS FALLS-WADENA-FAR S RICHLAND
COUNTY AS MOSTLY LIQUID THRU MON AFTN. HEAVY SNOW AXIS AT TIME
ROX-GFK-JMS. 925 MB WINDS INCREASE WITH EURO STILL THE WINDIEST
WITH 50-60 KTS WITH GFS 45KTS OR SO. REGARDLESS ENOUGH WIND AND
SNOW TO LIKELY CAUSE BLIZZARD CONDITIONS TO DEVELOP THRU THE DAY
MONDAY IN NRN/CNTRL RRV SOUTHWESTWARD. STILL ENOUGH TIMING
DIFFERENCES AND HOW MUCH SNOWFALL AND EVENT STILL MOSTLY 12Z MONDAY
AND AFTERWARDS WILL STAY WITH WATCHES. BUT WITH PTYPE ISSUES AND
TIMING DID ADJUST START TIMES.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 410 AM CDT SUN MAR 30 2014
SNOW BAND WILL SHIFT EAST SLOWLY THRU THE FCST AREA MONDAY ENDING
IN THE FAR EAST TUESDAY MORNING. WPC WWD AND PREFERENCE FOR A BIT
FARTHER NORTHWEST TRACK GIVES A WIDE 12-15 INCH BAND COOPERSTOWN-
VALLEY CITY THROUGH FARGO-GRAND FORKS TO BAUDETTE-ROSEAU-BEMIDJI.
A BIT LESS NORTH AND SOUTH OF THIS BAND. WITH SLOWER PROGRESSION
DID EXTEND WATCH ENDING TIME TO 12Z TUESDAY. QUIETER TUESDAY AS
HIGH MOVES IN.
WEDNESDAY THROUGH SATURDAY NIGHT...00 UTC GFS/ECMWF ARE IN FAIR
AGREEMENT BOTH SHOWING THE NEXT EASTERN PACIFIC SHORT-WAVE CRASH
ONTO THE CENTRAL CA COAST WEDNESDAY MORNING AND THEN MOVE IT
NORTHEASTWARD INTO CENTRAL IA BY FRIDAY AFTERNOON. THE ECMWF IS
STRONGER AT THIS TIME WITH A CLOSED 500 HPA LOW...WHEREAS THE GFS
MAINTAINS AN OPEN WAVE. AS A RESULT...THE ECMWF/S QPF IS MORE ROBUST
WITH ITS PRECIP SHIELD EXTENDING INTO THE SOUTHERN FORECAST AREA ON
FRIDAY. THE GFS KEEPS MOST PRECIP FARTHER SOUTH ACROSS EASTERN SD
INTO SOUTHERN MN. REMOVED ALL BLEND PRECIP WED/WED NIGHT WITH SFC
HIGH IN PLACE...BUT WILL EXTEND 20/30 POPS FROM SOUTH TO NORTH
THURS/THURS NIGHT MAINLY ACROSS THE SOUTHERN FORECAST AREA.
LINGERING PRECIP FRIDAY SHOULD GIVE WAY TO DRY CONDITIONS FOR THE
FIRST HALF OF THE WEEKEND. TEMPERATURES THROUGH THE PERIOD WILL
GRADUALLY INCREASE EACH DAY...BUT REMAIN BELOW EARLY APRIL NORMALS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1244 PM CDT SUN MAR 30 2014
MVFR CIGS ARE DROPPING SOUTH ACROSS NORTHEAST NORTH DAKOTA BEHIND
THE WEAK COLD FRONT THAT HAS SHIFTED WINDS FROM THE NORTH.
ANTICIPATE THAT THESE LOWER CIGS WILL EVENTUALLY INVADE ALL TAF
SITES...BUT NOT SURE EXACTLY WHEN. FOLLOWED THE LATEST RAP GUIDANCE
FOR TIMING. CONDITIONS WILL QUICKLY DETERIORATE TO IFR/LIFR
CONDITIONS MONDAY MORNING AS HEAVY SNOW AND STRONG WINDS BECOME
POSSIBLE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...BLIZZARD WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR
NDZ039-049-052-053.
BLIZZARD WATCH FROM LATE TONIGHT THROUGH TUESDAY MORNING FOR
NDZ006>008-014>016-024-026>030-038-054.
MN...BLIZZARD WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR
MNZ002-003-029.
WINTER STORM WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY MORNING
FOR MNZ022>024-027-028.
BLIZZARD WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING FOR
MNZ030-040.
BLIZZARD WATCH FROM LATE TONIGHT THROUGH TUESDAY MORNING FOR
MNZ001-004-007.
WINTER STORM WATCH FROM LATE TONIGHT THROUGH TUESDAY MORNING FOR
MNZ005-006-008-009-013>017.
WINTER STORM WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING
FOR MNZ031-032.
&&
$$
UPDATE...GODON
SHORT TERM...RIDDLE
LONG TERM...RIDDLE/ROGERS
AVIATION...TG
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
452 PM EDT SUN MAR 30 2014
.SYNOPSIS...
A DEEPENING STORM ON THE NJ COAST MOVE VERY SLOWLY EAST OVERNIGHT.
A RIDGE OF HIGH PRESSURE WILL SLIDE OVERHEAD ON MONDAY AND LEAD
TO FAIR AND MILDER TEMPERATURES FOR THE FIRST HALF OF THE WEEK.
UNSETTLED CONDITIONS ARE EXPECTED TO RETURN FOR THE SECOND HALF OF
THE WEEK.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
445PM UPDATE...
RAPID CHANGES TAKING PLACE AS THE INTENSE MESOSCALE BAND OF
PRECIP IS GENERATING JUST ENOUGH COLD AIR TO CREATE LOCALLY HEAVY
SNOW. WEB CAMS AND REPORTS WARRANT THE ISSUANCE OF AN ADVISORY
INTO THE EVENING AS CONDITIONS VARY WILDLY FROM NOTHING AT ALL
HAPPENING OVER MOST OF CENTRAL AND WESTERN PA...TO HEAVY SNOW AND
SLEET AND RAIN OVER ABOUT THE EASTERN 1/3 OR SO OF OUR FORECAST
AREA.
THE SLOW MOVING BAND OF RAIN-SNOW-SLEET WILL CONTINUE TO ONLY
SLOWLY DRIFT OVER MY EASTERN ZONES. WHERE PRECIP RATES ARE INTENSE
ENOUGH...SOME LOCALLY HEAVY SNOW IS BEING OBSERVED. STILL THINKING
MOST OF THE SNOW SHOULD BE CONFINED TO GRASSY SURFACES...BUT THE
ROADS WILL BE SLIPPERY AND SLUSHY IN THE MORE PERSISTENT HEAVY
SNOW BANDS.
FROM EARLIER...
REGIONAL RADAR MOSAIC AT 19Z SHOWS AN EXTENSIVE...AND NEARLY
STATIONARY BAND OF MODERATE TO HEAVY RAIN OVER THE SUSQ MAINSTEM
/AND POINTS WEST TO INTERSTATE 81 ACROSS SCENT PENN/
THIS AREA OF PERSISTENT/HEAVY PRECIP IS OCCURRING AS A RESULT OF
THE COMBINED EFFECTS OF A MODERATELY STRONG DEFORMATION BAND AND
MID-LEVEL FGEN FORCING /ENHANCED BY A WELL-DEFINED SPOKE OF
VORTICITY SPIRALING AROUND THE NWRN EDGE OF THE SLOW MOVING UPPER
LOW CENTERED OVER THE DELMARVA PENINSULA/.
FLOOD WATCH REMAINS IN EFFECT UNTIL 8 PM THIS EVENING FOR THE
EASTERN HALF OF THE STATE WHILE THE LOCALIZED VERY HEAVY RAIN
ACROSS PORTIONS OF SCENT PENN HAVE PROMPTED US TO UPGRADE OUR
EARLIER FLOOD ADVISORY TO A FLOOD WARNING FOR ADAMS AND YORK
COUNTIES...WITH THE YELLOW BREECHES CREEK AT CAMP HILL FORECAST TO
EXCEED FS TONIGHT.
DEEP LAYER CAA WILL HELP TO GRADUALLY MIX...THEN CHANGE THE RAIN
OVER TO WET SNOW ACROSS EVEN THE SOUTHERN VALLEYS LATE THIS
AFTERNOON AND EARLY THIS EVENING...WHILE A GRADUAL DECREASING
TREND IN THE LIGHTER SNOW OCCURS ACROSS THE NRN AND WESTERN MTNS
OF THE STATE.
CANCELLED THE WINT WX ADVISORY FOR ALL BUT SULLIVAN COUNTY...WHICH
STILL RUNS THROUGH 4 PM TODAY. THIS MAY NEED TO BE EXTENDED A FEW
HOURS BASED ON THE LATEST 18Z RAP.
15Z/18Z RAP DOING AN EXCELLENT JOB SIMULATING THIS NEARLY
STATIONARY/SLOWLY WWD DRIFTING BAND OF HEAVIER PRECIP SWIRLING
AROUND THE 546 DAM UPPER LOW. THESE MODELS SHOW A TREND OF
MAINTAINING THIS RATHER HIGH RAINFALL INTENSITY /AND RATE OF AT
LEAST .3 TO .6 OF AN INCH PER HOUR/ BEFORE CHANGING IT TO A FEW
TO SVRL HOUR PERIOD OF /WET/ SNOW EARLY THIS EVENING...THEN
SLOWLY WEAKENING THE PRECIP RATES AND SLOWLY SHIFTING THE AREA
EAST ACROSS THE LOWER SUSQ REGION AND ECENT MTNS TONIGHT.
ADDITIONAL QPF /LIKELY BETWEEN 0.5-1.0 INCH OF ADDITIONAL RAIN AND
MELTED WET SNOW ACROSS THE SCENT ZONES AND LOWER SUSQ REGION/
WILL GRADUALLY TREND LOWER...THEN DIMINISH QUICKLY AS YOU HEAD NW
TWD THE I-99/RT 220 CORRIDOR.
THIS WILL LEAD TO A RAIN/WET SNOW MIXTURE WITH LITTLE OR NO ACCUM
AT ELEVATIONS AOB 1400 FT MSL. MAINLY RAIN /MDT TO HVY AT TIMES/
WILL PERSIST ACROSS THE LOWER SUSQ VALLEY THROUGH THE LATE
AFTERNOON WITH BIG...SLOPPY WET SNOWFLAKES MIXING IN TO THE WEST
OF I-83.
TEMPS ALOFT REMAIN JUST WARM ENOUGH FOR ALL RAIN IN THE FAR SE
INVOF KLNS. SOME OF THE HIGHER TERRAIN OF SCENT...AND ECENT PENN
/MAINLY AOA 1400 FT MSL/ COULD START TO SEE A GROUND COVERING OF
WET SNOW LATER THIS AFTERNOON AND EVENING AS A FEW ADDITIONAL
SPOKES OF VORTICITY AND N/S PRECIP BANDS ROTATE WWD AROUND THE
UPPER LOW.
2-DAY STORM TOTAL RAINFALL AND MELTED SNOW BY MIDNIGHT TONIGHT
HAVE REACHED 4-5 INCHES OVER PORTIONS OF SCENT PENN /ADAMS AND
YORK COUNTIES/...JUST WEST OF THE SUSQ RIVER...WHILE OTHER
LOCATIONS THROUGHOUT EASTERN CENTRAL AND EASTERN SECTIONS OF THE
CWA COME IN BETWEEN 1.5 AND 2.5 INCHES.
WET SNOW WILL CONTINUE TO TAPER OFF IN THE WEST THROUGH THIS
AFTERNOON AS THE CENTER OF THE UPPER LOW MOVES FARTHER TO THE EAST
AND SIGNIFICANT LIFT EXITS WITH IT.
THE OTHER INCREASINGLY NOTABLE ASPECT OF THE WEATHER WILL BE THE
GUSTY 30-40 MPH WIND THAT WILL BE DEVELOPING IN THE STRENGTHENING
LLVL PRESSURE GRADIENT JUST IN THE WAKE OF THIS CURRENT SYSTEM.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH 6 PM MONDAY/...
RAIN AND WET SNOW WILL CONTINUE INTO THE NIGHT OVER THE FAR
EAST...WITH MINOR ACCUMS OF A COATING TO ONE INCH /PERHAPS 2
INCHES ON THE RIDGES AOA 1600 FT MSL FROM SCHUYLKILL CTY...NORTH
TO SULLIVAN CTY.
HIGH PRESSURE RIDGE BUILDS IN BEHIND THE STORM FOR MONDAY.
RESIDUAL MSTR WILL PROBABLY HOLD CLOUDS IN THE WRN MTS AT
FIRST...BUT CLEARING SHOULD OCCUR EVERYWHERE THROUGH THE
AFTERNOON. TEMPS SHOULD RECOVER VERY NICELY AS 8H TEMPS SHOOT BACK
INTO THE MID SINGLE DIGITS ABOVE ZERO. AREAS WITH SNOW ON THE
GROUND MAY HAVE A BIT OF A DELAY IN THE RECOVERY...BUT ALMOST-
APRIL SUNSHINE SHOULD DO SOME GOOD MELTING.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
HIGH PRESSURE WILL CONTINUE TO BUILD OVER THE NORTHEAST MONDAY
NIGHT INTO TUESDAY.
A LARGE UPPER LEVEL LOW WILL MOVE THROUGH SOUTHERN CANADA/GREAT
LAKES REGION TUESDAY EVENING. THIS SYSTEM CONTINUES TO BE MOISTURE
STARVED SO PRECIPITATION IS LESS LIKELY. WEAK SOUTHWESTERLY FLOW
COULD ALLOW FOR A SLIGHT CHANCE FOR PRECIPITATION ALONG THE SW
MTNS...HOWEVER THIS IS LESS LIKELY CONSIDERING ANY LINGERING HIGH
PRESSURE. A STATIONARY BOUNDARY BETWEEN THE SYSTEMS SHOULD LIE
OVER THE REGION WEDNESDAY INTO EARLY THURSDAY. THIS COULD
ALLOW...FOR PERIODS OF LIGHT SHOWERS. A WEAK RIDGE COULD STIFLE
PRECIP EARLY THURSDAY. A DEEPENING UPPER LEVEL LOW WILL MOVE
THROUGH THE MIDWEST THURSDAY NIGHT INTO FRIDAY...AND THROUGH THE
REGION SATURDAY. THIS SYSTEM WILL BRING THE NEXT BEST CHANCE FOR
PRECIPITATION. THERE IS STILL VARIATION ON POSITION AND
TIMING...BUT RAIN SHOWERS ARE POSSIBLE AS EARLY AS THURSDAY
AFTERNOON AS THE ASSOCIATED WARM FRONT NOSES INTO PENNSYLVANIA.
THE COLD FRONT WILL MOVE THROUGH THE AREA DURING THE FIRST PART OF
THE WEEKEND BRINGING MORE RAIN. INTO LATE SATURDAY.
&&
.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
A COMPLEX AREA OF LOW PRESSURE OVER THE DELMARVA REGION THIS
AFTERNOON WILL MOVE ONLY SLOWLY EAST THROUGH THE RES OF THE
DAYLIGHT HOURS...KEEPING WEATHER UNSETTLED THROUGH MUCH OF THE
TAF PERIOD. WIDESPREAD MVFR CIGS AND VISBYS /WITH AREAS OF IFR/
IN RAIN WET SNOW WILL PERSIST THROUGH THIS AFTERNOON...WITH
IFR/LIFR CONDS MOST PREVALENT ACROSS THE WRN AND NWRN MTNS...JST
AND BFD.
AS THE DEEP SFC LOW REMAINS NEAR TO THE COAST...WINDS SUSTAINED
BETWEEN 15-25 MPH WITH HIGHER GUSTS WILL BE PREVALENT AT ALL
AIRFIELDS INTO TONIGHT. HIGH CONFIDENCE IN GUSTS AOB 25KTS BETWEEN
18Z TODAY AND 04Z MONDAY.
OUTLOOK...
MON...LOW CIGS RAIN/SNOW ENDING ERN SXNS EARLY BCMG VFR. MVFR/IFR
CIGS WEST BCMG VFR.
TUE...VFR WITH OCNL MVFR PSBL IN SCT SHRA ASSOCD WITH COLD FRONT.
WED-THU...VFR/MVFR WITH CHC OF RAIN.
&&
.HYDROLOGY...
FLOOD WATCH CONTINUES FOR ABOUT EASTERN THIRD OF CWA THROUGH
THIS EVENING. THE CLOSED UPPER LOW IS EXPECTED TO CLOSE TRACK
SLOWLY TO THE EAST AND OFF MID ATLC COAST LATE TODAY AND TONIGHT.
THIS WILL PRODUCE A FEW MORE NWWD BANDS OF MDT TO HEAVY RAIN OVER
SCENT AND EASTERN PENN TODAY.
THE HIGHER AMOUNTS STILL LOOK TO BE FOCUSED ACROSS THE SCENT
MTNS...LOWER SUSQ VALLEY AND ECENT MTNS...AS THE DEFORMATION ZONE
TO THE N/W OF THE UPPER LOW CENTER MOVES TO THE EAST AS WELL. THE
RAIN MAY NOT MOVE OUT ENTIRELY UNTIL MIDNIGHT OR LATER. THUS...THE
WATCH MAY NEED TO BE EXTENDED TO COVER THE PERIOD OF RUNOFF. BUT
HAVE NOT MADE THIS MOVE QUITE YET. LOCALIZED STORM TOTAL AMOUNTS
OF UP TO 2 INCHES ARE LIKELY OVER THE EAST. THIS WILL CAUSE
SIGNIFICANT RISES ON THE SMALL STREAMS AND SOME MAY BE RISING TO
BANKFULL BEFORE NOON. MANY OF THE LARGER WATERWAYS MAY GET TO
THEIR CAUTION STAGES...BUT THESE EFFECTS WOULD BE DELAYED FOR A
PERIOD OR TWO. THE MAINSTEM RIVER IS ALREADY PROGGED TO REACH
CAUTION STAGES AT MANY PLACES WITH CURRENT QPF IN THE HYDRO MODEL.
MMEFS PROBS FOR EXCEDENCE MAY BE UNDERDONE IN THE SREF
DATA...MAINLY DUE TO THE SHIFTING QPF AREAS/CENTERS AMONGST THE
MEMBERS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR PAZ028-036-037-041-
042-046-049>053-056>059-063>066.
WINTER WEATHER ADVISORY UNTIL 8 PM EDT THIS EVENING FOR PAZ042-
051>053-056>059-063>066.
&&
$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...LA CORTE/LAMBERT
SHORT TERM...DANGELO/LAMBERT
LONG TERM...CERU/COLBERT
AVIATION...LAMBERT/GARTNER
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
426 PM EDT SUN MAR 30 2014
.SYNOPSIS...
A DEEPENING STORM WILL MOVE VERY SLOWLY EAST FROM THE VIRGINIA
PIEDMONT TO THE SOUTHERN NEW JERSEY COAST BY SUNDAY EVENING. A
RIDGE OF HIGH PRESSURE WILL SLIDE OVERHEAD ON MONDAY AND LEAD TO
FAIR AND MILDER TEMPERATURES FOR THE FIRST HALF OF THE WEEK.
UNSETTLED CONDITIONS ARE EXPECTED TO RETURN FOR THE SECOND HALF OF
THE WEEK.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
AS OF 330PM...A SLOW MOVING BAND OF RAIN-SNOW-SLEET CONTINUED TO
ONLY SLOWLY DRIFT OVER MY EASTERN ZONES. MADE SOME FAST CHANGES TO
THE WINTER WEATHER ADVISORY FOR SULLIVAN COUNTY TO EXTEND IT INTO
THE EVENING. I ALSO INCLUDED A SLUSHY INCH OR SNOW POSSIBLE OVER
THE LOWER SUSQ VALLEY WHERE A WINTRY MIX OF SLEET AND SNOW IS
OCCURRING UNDER THE BAND. WHERE PRECIP RATES ARE HEAVY
ENOUGH...SOME LOCALLY HEAVY SNOW IS BEING OBSERVED. STILL
THINKING MOST OF THE SNOW SHOULD BE CONFINED TO GRASSY
SURFACES...BUT THE ROADS COULD BECOME SLIPPERY AND SLUSHY IN THE
MORE PERSISTENT HEAVY SNOW BANDS.
FROM EARLIER...
REGIONAL RADAR MOSAIC AT 19Z SHOWS AN EXTENSIVE...AND NEARLY
STATIONARY BAND OF MODERATE TO HEAVY RAIN OVER THE SUSQ MAINSTEM
/AND POINTS WEST TO INTERSTATE 81 ACROSS SCENT PENN/
THIS AREA OF PERSISTENT/HEAVY PRECIP IS OCCURRING AS A RESULT OF
THE COMBINED EFFECTS OF A MODERATELY STRONG DEFORMATION BAND AND
MID-LEVEL FGEN FORCING /ENHANCED BY A WELL-DEFINED SPOKE OF
VORTICITY SPIRALING AROUND THE NWRN EDGE OF THE SLOW MOVING UPPER
LOW CENTERED OVER THE DELMARVA PENINSULA/.
FLOOD WATCH REMAINS IN EFFECT UNTIL 8 PM THIS EVENING FOR THE
EASTERN HALF OF THE STATE WHILE THE LOCALIZED VERY HEAVY RAIN
ACROSS PORTIONS OF SCENT PENN HAVE PROMPTED US TO UPGRADE OUR
EARLIER FLOOD ADVISORY TO A FLOOD WARNING FOR ADAMS AND YORK
COUNTIES...WITH THE YELLOW BREECHES CREEK AT CAMP HILL FORECAST TO
EXCEED FS TONIGHT.
DEEP LAYER CAA WILL HELP TO GRADUALLY MIX...THEN CHANGE THE RAIN
OVER TO WET SNOW ACROSS EVEN THE SOUTHERN VALLEYS LATE THIS
AFTERNOON AND EARLY THIS EVENING...WHILE A GRADUAL DECREASING
TREND IN THE LIGHTER SNOW OCCURS ACROSS THE NRN AND WESTERN MTNS
OF THE STATE.
CANCELLED THE WINT WX ADVISORY FOR ALL BUT SULLIVAN COUNTY...WHICH
STILL RUNS THROUGH 4 PM TODAY. THIS MAY NEED TO BE EXTENDED A FEW
HOURS BASED ON THE LATEST 18Z RAP.
15Z/18Z RAP DOING AN EXCELLENT JOB SIMULATING THIS NEARLY
STATIONARY/SLOWLY WWD DRIFTING BAND OF HEAVIER PRECIP SWIRLING
AROUND THE 546 DAM UPPER LOW. THESE MODELS SHOW A TREND OF
MAINTAINING THIS RATHER HIGH RAINFALL INTENSITY /AND RATE OF AT
LEAST .3 TO .6 OF AN INCH PER HOUR/ BEFORE CHANGING IT TO A FEW
TO SVRL HOUR PERIOD OF /WET/ SNOW EARLY THIS EVENING...THEN
SLOWLY WEAKENING THE PRECIP RATES AND SLOWLY SHIFTING THE AREA
EAST ACROSS THE LOWER SUSQ REGION AND ECENT MTNS TONIGHT.
ADDITIONAL QPF /LIKELY BETWEEN 0.5-1.0 INCH OF ADDITIONAL RAIN AND
MELTED WET SNOW ACROSS THE SCENT ZONES AND LOWER SUSQ REGION/
WILL GRADUALLY TREND LOWER...THEN DIMINISH QUICKLY AS YOU HEAD NW
TWD THE I-99/RT 220 CORRIDOR.
THIS WILL LEAD TO A RAIN/WET SNOW MIXTURE WITH LITTLE OR NO ACCUM
AT ELEVATIONS AOB 1400 FT MSL. MAINLY RAIN /MDT TO HVY AT TIMES/
WILL PERSIST ACROSS THE LOWER SUSQ VALLEY THROUGH THE LATE
AFTERNOON WITH BIG...SLOPPY WET SNOWFLAKES MIXING IN TO THE WEST
OF I-83.
TEMPS ALOFT REMAIN JUST WARM ENOUGH FOR ALL RAIN IN THE FAR SE
INVOF KLNS. SOME OF THE HIGHER TERRAIN OF SCENT...AND ECENT PENN
/MAINLY AOA 1400 FT MSL/ COULD START TO SEE A GROUND COVERING OF
WET SNOW LATER THIS AFTERNOON AND EVENING AS A FEW ADDITIONAL
SPOKES OF VORTICITY AND N/S PRECIP BANDS ROTATE WWD AROUND THE
UPPER LOW.
2-DAY STORM TOTAL RAINFALL AND MELTED SNOW BY MIDNIGHT TONIGHT
HAVE REACHED 4-5 INCHES OVER PORTIONS OF SCENT PENN /ADAMS AND
YORK COUNTIES/...JUST WEST OF THE SUSQ RIVER...WHILE OTHER
LOCATIONS THROUGHOUT EASTERN CENTRAL AND EASTERN SECTIONS OF THE
CWA COME IN BETWEEN 1.5 AND 2.5 INCHES.
WET SNOW WILL CONTINUE TO TAPER OFF IN THE WEST THROUGH THIS
AFTERNOON AS THE CENTER OF THE UPPER LOW MOVES FARTHER TO THE EAST
AND SIGNIFICANT LIFT EXITS WITH IT.
THE OTHER INCREASINGLY NOTABLE ASPECT OF THE WEATHER WILL BE THE
GUSTY 30-40 MPH WIND THAT WILL BE DEVELOPING IN THE STRENGTHENING
LLVL PRESSURE GRADIENT JUST IN THE WAKE OF THIS CURRENT SYSTEM.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH 6 PM MONDAY/...
RAIN AND WET SNOW WILL CONTINUE INTO THE NIGHT OVER THE FAR
EAST...WITH MINOR ACCUMS OF A COATING TO ONE INCH /PERHAPS 2
INCHES ON THE RIDGES AOA 1600 FT MSL FROM SCHUYLKILL CTY...NORTH
TO SULLIVAN CTY.
HIGH PRESSURE RIDGE BUILDS IN BEHIND THE STORM FOR MONDAY.
RESIDUAL MSTR WILL PROBABLY HOLD CLOUDS IN THE WRN MTS AT
FIRST...BUT CLEARING SHOULD OCCUR EVERYWHERE THROUGH THE
AFTERNOON. TEMPS SHOULD RECOVER VERY NICELY AS 8H TEMPS SHOOT BACK
INTO THE MID SINGLE DIGITS ABOVE ZERO. AREAS WITH SNOW ON THE
GROUND MAY HAVE A BIT OF A DELAY IN THE RECOVERY...BUT ALMOST-
APRIL SUNSHINE SHOULD DO SOME GOOD MELTING.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
HIGH PRESSURE WILL CONTINUE TO BUILD OVER THE NORTHEAST MONDAY
NIGHT INTO TUESDAY.
A LARGE UPPER LEVEL LOW WILL MOVE THROUGH SOUTHERN CANADA/GREAT
LAKES REGION TUESDAY EVENING. THIS SYSTEM CONTINUES TO BE MOISTURE
STARVED SO PRECIPITATION IS LESS LIKELY. WEAK SOUTHWESTERLY FLOW
COULD ALLOW FOR A SLIGHT CHANCE FOR PRECIPITATION ALONG THE SW
MTNS...HOWEVER THIS IS LESS LIKELY CONSIDERING ANY LINGERING HIGH
PRESSURE. A STATIONARY BOUNDARY BETWEEN THE SYSTEMS SHOULD LIE
OVER THE REGION WEDNESDAY INTO EARLY THURSDAY. THIS COULD
ALLOW...FOR PERIODS OF LIGHT SHOWERS. A WEAK RIDGE COULD STIFLE
PREICIP EARLY THURSDAY.
A DEEPENING UPPER LEVEL LOW WILL MOVE THROUGH THE MIDWEST
THURSDAY NIGHT INTO FRIDAY...AND THROUGH THE REGION SATURDAY. THIS
SYSTEM WILL BRING THE NEXT BEST CHANCE FOR PRECIPITATION. THERE
IS STILL VARIATION ON POSITION AND TIMING...BUT RAIN SHOWERS ARE
POSSIBLE AS EARLY AS THURSDAY AFTERNOON AS THE ASSOCIATED WARM
FRONT NOSES INTO PENNSYLVANIA. THE COLD FRONT WILL MOVE THROUGH
THE AREA DURING THE FIRST PART OF THE WEEKEND BRINGING MORE RAIN.
INTO LATE SATURDAY.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
A COMPLEX AREA OF LOW PRESSURE OVER THE DELMARVA REGION THIS
AFTERNOON WILL MOVE ONLY SLOWLY EAST THROUGH THE RES OF THE
DAYLIGHT HOURS...KEEPING WEATHER UNSETTLED THROUGH MUCH OF THE
TAF PERIOD. WIDESPREAD MVFR CIGS AND VISBYS /WITH AREAS OF IFR/
IN RAIN WET SNOW WILL PERSIST THROUGH THIS AFTERNOON...WITH
IFR/LIFR CONDS MOST PREVALENT ACROSS THE WRN AND NWRN MTNS...JST
AND BFD.
AS THE DEEP SFC LOW REMAINS NEAR TO THE COAST...WINDS SUSTAINED
BETWEEN 15-25 MPH WITH HIGHER GUSTS WILL BE PREVALENT AT ALL
AIRFIELDS INTO TONIGHT. HIGH CONFIDENCE IN GUSTS AOB 25KTS BETWEEN
18Z TODAY AND 04Z MONDAY.
OUTLOOK...
MON...LOW CIGS RAIN/SNOW ENDING ERN SXNS EARLY BCMG VFR. MVFR/IFR
CIGS WEST BCMG VFR.
TUE...VFR WITH OCNL MVFR PSBL IN SCT SHRA ASSOCD WITH COLD FRONT.
WED-THU...VFR/MVFR WITH CHC OF RAIN.
&&
.HYDROLOGY...
FLOOD WATCH CONTINUES FOR ABOUT EASTERN THIRD OF CWA THROUGH
THIS EVENING. THE CLOSED UPPER LOW IS EXPECTED TO CLOSE TRACK
SLOWLY TO THE EAST AND OFF MID ATLC COAST LATE TODAY AND TONIGHT.
THIS WILL PRODUCE A FEW MORE NWWD BANDS OF MDT TO HEAVY RAIN OVER
SCENT AND EASTERN PENN TODAY.
THE HIGHER AMOUNTS STILL LOOK TO BE FOCUSED ACROSS THE SCENT
MTNS...LOWER SUSQ VALLEY AND ECENT MTNS...AS THE DEFORMATION ZONE
TO THE N/W OF THE UPPER LOW CENTER MOVES TO THE EAST AS WELL. THE
RAIN MAY NOT MOVE OUT ENTIRELY UNTIL MIDNIGHT OR LATER. THUS...THE
WATCH MAY NEED TO BE EXTENDED TO COVER THE PERIOD OF RUNOFF. BUT
HAVE NOT MADE THIS MOVE QUITE YET. LOCALIZED STORM TOTAL AMOUNTS
OF UP TO 2 INCHES ARE LIKELY OVER THE EAST. THIS WILL CAUSE
SIGNIFICANT RISES ON THE SMALL STREAMS AND SOME MAY BE RISING TO
BANKFULL BEFORE NOON. MANY OF THE LARGER WATERWAYS MAY GET TO
THEIR CAUTION STAGES...BUT THESE EFFECTS WOULD BE DELAYED FOR A
PERIOD OR TWO. THE MAINSTEM RIVER IS ALREADY PROGGED TO REACH
CAUTION STAGES AT MANY PLACES WITH CURRENT QPF IN THE HYDRO MODEL.
MMEFS PROBS FOR EXCEDENCE MAY BE UNDERDONE IN THE SREF
DATA...MAINLY DUE TO THE SHIFTING QPF AREAS/CENTERS AMONGST THE
MEMBERS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR PAZ028-036-037-041-
042-046-049>053-056>059-063>066.
WINTER WEATHER ADVISORY UNTIL 8 PM EDT THIS EVENING FOR PAZ042.
&&
$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...LA CORTE/LAMBERT
SHORT TERM...DANGELO/LAMBERT
LONG TERM...CERU/COLBERT
AVIATION...LAMBERT/GARTNER
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
350 PM EDT SUN MAR 30 2014
.SYNOPSIS...
A DEEPENING STORM WILL MOVE VERY SLOWLY EAST FROM THE VIRGINIA
PIEDMONT TO THE SOUTHERN NEW JERSEY COAST BY SUNDAY EVENING. A
RIDGE OF HIGH PRESSURE WILL SLIDE OVERHEAD ON MONDAY AND LEAD TO
FAIR AND MILDER TEMPERATURES FOR THE FIRST HALF OF THE WEEK.
UNSETTLED CONDITIONS ARE EXPECTED TO RETURN FOR THE SECOND HALF OF
THE WEEK.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
AS OF 330PM...A SLOW MOVING BAND OF RAIN-SNOW-SLEET CONTINUED TO
ONLY SLOWLY DRIFT OVER MY EASTERN ZONES. MADE SOME FAST CHANGES TO
THE WINTER WEATHER ADVISORY FOR SULLIVAN COUNTY TO EXTEND IT INTO
THE EVENING. I ALSO INCLUDED A SLUSHY INCH OR SNOW POSSIBLE OVER
THE LOWER SUSQ VALLEY WHERE A WINTRY MIX OF SLEET AND SNOW IS
OCCURRING UNDER THE BAND. WHERE PRECIP RATES ARE HEAVY
ENOUGH...SOME LOCALLY HEAVY SNOW IS BEING OBSERVED. STILL
THINKING MOST OF THE SNOW SHOULD BE CONFINED TO GRASSY
SURFACES...BUT THE ROADS COULD BECOME SLIPPERY AND SLUSHY IN THE
MORE PERSISTENT HEAVY SNOW BANDS.
FROM EARLIER...
REGIONAL RADAR MOSAIC AT 19Z SHOWS AN EXTENSIVE...AND NEARLY
STATIONARY BAND OF MODERATE TO HEAVY RAIN OVER THE SUSQ MAINSTEM
/AND POINTS WEST TO INTERSTATE 81 ACROSS SCENT PENN/
THIS AREA OF PERSISTENT/HEAVY PRECIP IS OCCURRING AS A RESULT OF
THE COMBINED EFFECTS OF A MODERATELY STRONG DEFORMATION BAND AND
MID-LEVEL FGEN FORCING /ENHANCED BY A WELL-DEFINED SPOKE OF
VORTICITY SPIRALING AROUND THE NWRN EDGE OF THE SLOW MOVING UPPER
LOW CENTERED OVER THE DELMARVA PENINSULA/.
FLOOD WATCH REMAINS IN EFFECT UNTIL 8 PM THIS EVENING FOR THE
EASTERN HALF OF THE STATE WHILE THE LOCALIZED VERY HEAVY RAIN
ACROSS PORTIONS OF SCENT PENN HAVE PROMPTED US TO UPGRADE OUR
EARLIER FLOOD ADVISORY TO A FLOOD WARNING FOR ADAMS AND YORK
COUNTIES...WITH THE YELLOW BREECHES CREEK AT CAMP HILL FORECAST TO
EXCEED FS TONIGHT.
DEEP LAYER CAA WILL HELP TO GRADUALLY MIX...THEN CHANGE THE RAIN
OVER TO WET SNOW ACROSS EVEN THE SOUTHERN VALLEYS LATE THIS
AFTERNOON AND EARLY THIS EVENING...WHILE A GRADUAL DECREASING
TREND IN THE LIGHTER SNOW OCCURS ACROSS THE NRN AND WESTERN MTNS
OF THE STATE.
CANCELLED THE WINT WX ADVISORY FOR ALL BUT SULLIVAN COUNTY...WHICH
STILL RUNS THROUGH 4 PM TODAY. THIS MAY NEED TO BE EXTENDED A FEW
HOURS BASED ON THE LATEST 18Z RAP.
15Z/18Z RAP DOING AN EXCELLENT JOB SIMULATING THIS NEARLY
STATIONARY/SLOWLY WWD DRIFTING BAND OF HEAVIER PRECIP SWIRLING
AROUND THE 546 DAM UPPER LOW. THESE MODELS SHOW A TREND OF
MAINTAINING THIS RATHER HIGH RAINFALL INTENSITY /AND RATE OF AT
LEAST .3 TO .6 OF AN INCH PER HOUR/ BEFORE CHANGING IT TO A FEW
TO SVRL HOUR PERIOD OF /WET/ SNOW EARLY THIS EVENING...THEN
SLOWLY WEAKENING THE PRECIP RATES AND SLOWLY SHIFTING THE AREA
EAST ACROSS THE LOWER SUSQ REGION AND ECENT MTNS TONIGHT.
ADDITIONAL QPF /LIKELY BETWEEN 0.5-1.0 INCH OF ADDITIONAL RAIN AND
MELTED WET SNOW ACROSS THE SCENT ZONES AND LOWER SUSQ REGION/
WILL GRADUALLY TREND LOWER...THEN DIMINISH QUICKLY AS YOU HEAD NW
TWD THE I-99/RT 220 CORRIDOR.
THIS WILL LEAD TO A RAIN/WET SNOW MIXTURE WITH LITTLE OR NO ACCUM
AT ELEVATIONS AOB 1400 FT MSL. MAINLY RAIN /MDT TO HVY AT TIMES/
WILL PERSIST ACROSS THE LOWER SUSQ VALLEY THROUGH THE LATE
AFTERNOON WITH BIG...SLOPPY WET SNOWFLAKES MIXING IN TO THE WEST
OF I-83.
TEMPS ALOFT REMAIN JUST WARM ENOUGH FOR ALL RAIN IN THE FAR SE
INVOF KLNS. SOME OF THE HIGHER TERRAIN OF SCENT...AND ECENT PENN
/MAINLY AOA 1400 FT MSL/ COULD START TO SEE A GROUND COVERING OF
WET SNOW LATER THIS AFTERNOON AND EVENING AS A FEW ADDITIONAL
SPOKES OF VORTICITY AND N/S PRECIP BANDS ROTATE WWD AROUND THE
UPPER LOW.
2-DAY STORM TOTAL RAINFALL AND MELTED SNOW BY MIDNIGHT TONIGHT
HAVE REACHED 4-5 INCHES OVER PORTIONS OF SCENT PENN /ADAMS AND
YORK COUNTIES/...JUST WEST OF THE SUSQ RIVER...WHILE OTHER
LOCATIONS THROUGHOUT EASTERN CENTRAL AND EASTERN SECTIONS OF THE
CWA COME IN BETWEEN 1.5 AND 2.5 INCHES.
WET SNOW WILL CONTINUE TO TAPER OFF IN THE WEST THROUGH THIS
AFTERNOON AS THE CENTER OF THE UPPER LOW MOVES FARTHER TO THE EAST
AND SIGNIFICANT LIFT EXITS WITH IT.
THE OTHER INCREASINGLY NOTABLE ASPECT OF THE WEATHER WILL BE THE
GUSTY 30-40 MPH WIND THAT WILL BE DEVELOPING IN THE STRENGTHENING
LLVL PRESSURE GRADIENT JUST IN THE WAKE OF THIS CURRENT SYSTEM.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH 6 PM MONDAY/...
RAIN AND WET SNOW WILL CONTINUE INTO THE NIGHT OVER THE FAR
EAST...WITH MINOR ACCUMS OF A COATING TO ONE INCH /PERHAPS 2
INCHES ON THE RIDGES AOA 1600 FT MSL FROM SCHUYLKILL CTY...NORTH
TO SULLIVAN CTY.
HIGH PRESSURE RIDGE BUILDS IN BEHIND THE STORM FOR MONDAY.
RESIDUAL MSTR WILL PROBABLY HOLD CLOUDS IN THE WRN MTS AT
FIRST...BUT CLEARING SHOULD OCCUR EVERYWHERE THROUGH THE
AFTERNOON. TEMPS SHOULD RECOVER VERY NICELY AS 8H TEMPS SHOOT BACK
INTO THE MID SINGLE DIGITS ABOVE ZERO. AREAS WITH SNOW ON THE
GROUND MAY HAVE A BIT OF A DELAY IN THE RECOVERY...BUT ALMOST-
APRIL SUNSHINE SHOULD DO SOME GOOD MELTING.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
LATEST MODEL SOLUTIONS CONTINUE TO SLOW DOWN THE PROGRESSION OF
THE INCOMING STORM. THIS SHOULD RESULT IN LINGERING SHOWERS OVER
THE EAST SUNDAY NIGHT. THE COLD NORTHERLY FLOW COULD ALLOW FOR A
RAIN SNOW MIX ALONG THE HIGHER ELEVATIONS WITH RAIN LINGERING INTO
MONDAY MORNING DEPENDING ON THE SPEED OF THE LOW. THE EC/GFS HAS
THE UPPER LOW FINALLY MOVING FURTHER INTO THE ATLANTIC BY LATE
MONDAY MORNING.
AT THIS POINT...MONDAY WILL BE ONE OF THE BEST DAYS OF THE EXTENDED
FORECAST WITH HIGH PRESSURE...FAIR SKIES...AND SEASONABLE
TEMPERATURES. ENSEMBLES AS A WHOLE ARE TRENDING WARMER IN THE NEXT
WEEK. SO MORE SEASONABLE TEMPERATURES ARE ON THE HORIZON. AN UPPER
LEVEL TROUGH WILL SLIDE ALONG THE NORTHERN BORDER LATE TUESDAY
EVENING. SYSTEM WILL BE MORE MOISTURE STARVED SO PRECIPITATION IS
LESS LIKELY. WEAK SOUTHWESTERLY FLOW COULD ALLOW FOR A SLIGHT CHANCE
FOR PRECIPITATION ALONG THE SW MTNS...HOWEVER THIS IS LESS LIKELY
CONSIDERING THE RIDGE THAT SHOULD BE IN PLACE. AN UPPER LEVEL LOW
MOVING THROUGH THE REGION LATE NEXT WEEK WILL BE THE NEXT CHANCE FOR
PRECIPITATION AFTER THIS WEEKENDS STORM. THERE IS STILL VARIATION ON
POSITION AND TIMING...BUT RAIN SHOWERS ARE POSSIBLE AS EARLY AS
THURSDAY AFTERNOON AS THE ASSOCIATED WARM FRONT NOSES INTO
PENNSYLVANIA. THE COLD FRONT WILL MOVE THROUGH THE AREA DURING THE
FIRST PART OF THE WEEKEND BRINGING MORE RAIN. DEPENDING ON THE
SPEED OF THE LOW...PRECIPITATION COULD LINGER INTO SUNDAY.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
A COMPLEX AREA OF LOW PRESSURE OVER THE DELMARVA REGION THIS
AFTERNOON WILL MOVE ONLY SLOWLY EAST THROUGH THE RES OF THE
DAYLIGHT HOURS...KEEPING WEATHER UNSETTLED THROUGH MUCH OF THE
TAF PERIOD. WIDESPREAD MVFR CIGS AND VISBYS /WITH AREAS OF IFR/
IN RAIN WET SNOW WILL PERSIST THROUGH THIS AFTERNOON...WITH
IFR/LIFR CONDS MOST PREVALENT ACROSS THE WRN AND NWRN MTNS...JST
AND BFD.
AS THE DEEP SFC LOW REMAINS NEAR TO THE COAST...WINDS SUSTAINED
BETWEEN 15-25 MPH WITH HIGHER GUSTS WILL BE PREVALENT AT ALL
AIRFIELDS INTO TONIGHT. HIGH CONFIDENCE IN GUSTS AOB 25KTS BETWEEN
18Z TODAY AND 04Z MONDAY.
OUTLOOK...
MON...LOW CIGS RAIN/SNOW ENDING ERN SXNS EARLY BCMG VFR. MVFR/IFR
CIGS WEST BCMG VFR.
TUE...VFR WITH OCNL MVFR PSBL IN SCT SHRA ASSOCD WITH COLD FRONT.
WED-THU...VFR/MVFR WITH CHC OF RAIN.
&&
.HYDROLOGY...
FLOOD WATCH CONTINUES FOR ABOUT EASTERN THIRD OF CWA THROUGH
THIS EVENING. THE CLOSED UPPER LOW IS EXPECTED TO CLOSE TRACK
SLOWLY TO THE EAST AND OFF MID ATLC COAST LATE TODAY AND TONIGHT.
THIS WILL PRODUCE A FEW MORE NWWD BANDS OF MDT TO HEAVY RAIN OVER
SCENT AND EASTERN PENN TODAY.
THE HIGHER AMOUNTS STILL LOOK TO BE FOCUSED ACROSS THE SCENT
MTNS...LOWER SUSQ VALLEY AND ECENT MTNS...AS THE DEFORMATION ZONE
TO THE N/W OF THE UPPER LOW CENTER MOVES TO THE EAST AS WELL. THE
RAIN MAY NOT MOVE OUT ENTIRELY UNTIL MIDNIGHT OR LATER. THUS...THE
WATCH MAY NEED TO BE EXTENDED TO COVER THE PERIOD OF RUNOFF. BUT
HAVE NOT MADE THIS MOVE QUITE YET. LOCALIZED STORM TOTAL AMOUNTS
OF UP TO 2 INCHES ARE LIKELY OVER THE EAST. THIS WILL CAUSE
SIGNIFICANT RISES ON THE SMALL STREAMS AND SOME MAY BE RISING TO
BANKFULL BEFORE NOON. MANY OF THE LARGER WATERWAYS MAY GET TO
THEIR CAUTION STAGES...BUT THESE EFFECTS WOULD BE DELAYED FOR A
PERIOD OR TWO. THE MAINSTEM RIVER IS ALREADY PROGGED TO REACH
CAUTION STAGES AT MANY PLACES WITH CURRENT QPF IN THE HYDRO MODEL.
MMEFS PROBS FOR EXCEDENCE MAY BE UNDERDONE IN THE SREF
DATA...MAINLY DUE TO THE SHIFTING QPF AREAS/CENTERS AMONGST THE
MEMBERS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR PAZ028-036-037-041-
042-046-049>053-056>059-063>066.
WINTER WEATHER ADVISORY UNTIL 8 PM EDT THIS EVENING FOR PAZ042.
&&
$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...LA CORTE/LAMBERT
SHORT TERM...DANGELO/LAMBERT
LONG TERM...CERU/COLBERT
AVIATION...LAMBERT/GARTNER
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
311 PM EDT SUN MAR 30 2014
.SYNOPSIS...
A DEEPENING STORM WILL MOVE VERY SLOWLY EAST FROM THE VIRGINIA
PIEDMONT TO THE SOUTHERN NEW JERSEY COAST BY SUNDAY EVENING. A
RIDGE OF HIGH PRESSURE WILL SLIDE OVERHEAD ON MONDAY AND LEAD TO
FAIR AND MILDER TEMPERATURES FOR THE FIRST HALF OF THE WEEK.
UNSETTLED CONDITIONS ARE EXPECTED TO RETURN FOR THE SECOND HALF OF
THE WEEK.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
REGIONAL RADAR MOSAIC AT 19Z SHOWS AN EXTENSIVE...AND NEARLY
STATIONARY BAND OF MODERATE TO HEAVY RAIN OVER THE SUSQ MAINSTEM
/AND POINTS WEST TO INTERSTATE 81 ACROSS SCENT PENN/
THIS AREA OF PERSISTENT/HEAVY PRECIP IS OCCURRING AS A RESULT OF
THE COMBINED EFFECTS OF A MODERATELY STRONG DEFORMATION BAND AND
MID-LEVEL FGEN FORCING /ENHANCED BY A WELL-DEFINED SPOKE OF
VORTICITY SPIRALING AROUND THE NWRN EDGE OF THE SLOW MOVING UPPER
LOW CENTERED OVER THE DELMARVA PENINSULA/.
FLOOD WATCH REMAINS IN EFFECT UNTIL 8 PM THIS EVENING FOR THE
EASTERN HALF OF THE STATE WHILE THE LOCALIZED VERY HEAVY RAIN
ACROSS PORTIONS OF SCENT PENN HAVE PROMPTED US TO UPGRADE OUR
EARLIER FLOOD ADVISORY TO A FLOOD WARNING FOR ADAMS AND YORK
COUNTIES...WITH THE YELLOW BREECHES CREEK AT CAMP HILL FORECAST TO
EXCEED FS TONIGHT.
DEEP LAYER CAA WILL HELP TO GRADUALLY MIX...THEN CHANGE THE RAIN
OVER TO WET SNOW ACROSS EVEN THE SOUTHERN VALLEYS LATE THIS
AFTERNOON AND EARLY THIS EVENING...WHILE A GRADUAL DECREASING
TREND IN THE LIGHTER SNOW OCCURS ACROSS THE NRN AND WESTERN MTNS
OF THE STATE.
CANCELLED THE WINT WX ADVISORY FOR ALL BUT SULLIVAN COUNTY...WHICH
STILL RUNS THROUGH 4 PM TODAY. THIS MAY NEED TO BE EXTENDED A FEW
HOURS BASED ON THE LATEST 18Z RAP.
15Z/18Z RAP DOING AN EXCELLENT JOB SIMULATING THIS NEARLY
STATIONARY/SLOWLY WWD DRIFTING BAND OF HEAVIER PRECIP SWIRLING
AROUND THE 546 DAM UPPER LOW. THESE MODELS SHOW A TREND OF
MAINTAINING THIS RATHER HIGH RAINFALL INTENSITY /AND RATE OF AT
LEAST .3 TO .6 OF AN INCH PER HOUR/ BEFORE CHANGING IT TO A FEW
TO SVRL HOUR PERIOD OF /WET/ SNOW EARLY THIS EVENING...THEN
SLOWLY WEAKENING THE PRECIP RATES AND SLOWLY SHIFTING THE AREA
EAST ACROSS THE LOWER SUSQ REGION AND ECENT MTNS TONIGHT.
ADDITIONAL QPF /LIKELY BETWEEN 0.5-1.0 INCH OF ADDITIONAL RAIN AND
MELTED WET SNOW ACROSS THE SCENT ZONES AND LOWER SUSQ REGION/
WILL GRADUALLY TREND LOWER...THEN DIMINISH QUICKLY AS YOU HEAD NW
TWD THE I-99/RT 220 CORRIDOR.
THIS WILL LEAD TO A RAIN/WET SNOW MIXTURE WITH LITTLE OR NO ACCUM
AT ELEVATIONS AOB 1400 FT MSL. MAINLY RAIN /MDT TO HVY AT TIMES/
WILL PERSIST ACROSS THE LOWER SUSQ VALLEY THROUGH THE LATE
AFTERNOON WITH BIG...SLOPPY WET SNOWFLAKES MIXING IN TO THE WEST
OF I-83.
TEMPS ALOFT REMAIN JUST WARM ENOUGH FOR ALL RAIN IN THE FAR SE
INVOF KLNS. SOME OF THE HIGHER TERRAIN OF SCENT...AND ECENT PENN
/MAINLY AOA 1400 FT MSL/ COULD START TO SEE A GROUND COVERING OF
WET SNOW LATER THIS AFTERNOON AND EVENING AS A FEW ADDITIONAL
SPOKES OF VORTICITY AND N/S PRECIP BANDS ROTATE WWD AROUND THE
UPPER LOW.
2-DAY STORM TOTAL RAINFALL AND MELTED SNOW BY MIDNIGHT TONIGHT
HAVE REACHED 4-5 INCHES OVER PORTIONS OF SCENT PENN /ADAMS AND
YORK COUNTIES/...JUST WEST OF THE SUSQ RIVER...WHILE OTHER
LOCATIONS THROUGHOUT EASTERN CENTRAL AND EASTERN SECTIONS OF THE
CWA COME IN BETWEEN 1.5 AND 2.5 INCHES.
WET SNOW WILL CONTINUE TO TAPER OFF IN THE WEST THROUGH THIS
AFTERNOON AS THE CENTER OF THE UPPER LOW MOVES FARTHER TO THE EAST
AND SIGNIFICANT LIFT EXITS WITH IT.
THE OTHER INCREASINGLY NOTABLE ASPECT OF THE WEATHER WILL BE THE
GUSTY 30-40 MPH WIND THAT WILL BE DEVELOPING IN THE STRENGTHENING
LLVL PRESSURE GRADIENT JUST IN THE WAKE OF THIS CURRENT SYSTEM.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH 6 PM MONDAY/...
RAIN AND WET SNOW WILL CONTINUE INTO THE NIGHT OVER THE FAR
EAST...WITH MINOR ACCUMS OF A COATING TO ONE INCH /PERHAPS 2
INCHES ON THE RIDGES AOA 1600 FT MSL FROM SCHUYLKILL CTY...NORTH
TO SULLIVAN CTY.
HIGH PRESSURE RIDGE BUILDS IN BEHIND THE STORM FOR MONDAY.
RESIDUAL MSTR WILL PROBABLY HOLD CLOUDS IN THE WRN MTS AT
FIRST...BUT CLEARING SHOULD OCCUR EVERYWHERE THROUGH THE
AFTERNOON. TEMPS SHOULD RECOVER VERY NICELY AS 8H TEMPS SHOOT BACK
INTO THE MID SINGLE DIGITS ABOVE ZERO. AREAS WITH SNOW ON THE
GROUND MAY HAVE A BIT OF A DELAY IN THE RECOVERY...BUT ALMOST-
APRIL SUNSHINE SHOULD DO SOME GOOD MELTING.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
LATEST MODEL SOLUTIONS CONTINUE TO SLOW DOWN THE PROGRESSION OF
THE INCOMING STORM. THIS SHOULD RESULT IN LINGERING SHOWERS OVER
THE EAST SUNDAY NIGHT. THE COLD NORTHERLY FLOW COULD ALLOW FOR A
RAIN SNOW MIX ALONG THE HIGHER ELEVATIONS WITH RAIN LINGERING INTO
MONDAY MORNING DEPENDING ON THE SPEED OF THE LOW. THE EC/GFS HAS
THE UPPER LOW FINALLY MOVING FURTHER INTO THE ATLANTIC BY LATE
MONDAY MORNING.
AT THIS POINT...MONDAY WILL BE ONE OF THE BEST DAYS OF THE EXTENDED
FORECAST WITH HIGH PRESSURE...FAIR SKIES...AND SEASONABLE
TEMPERATURES. ENSEMBLES AS A WHOLE ARE TRENDING WARMER IN THE NEXT
WEEK. SO MORE SEASONABLE TEMPERATURES ARE ON THE HORIZON. AN UPPER
LEVEL TROUGH WILL SLIDE ALONG THE NORTHERN BORDER LATE TUESDAY
EVENING. SYSTEM WILL BE MORE MOISTURE STARVED SO PRECIPITATION IS
LESS LIKELY. WEAK SOUTHWESTERLY FLOW COULD ALLOW FOR A SLIGHT CHANCE
FOR PRECIPITATION ALONG THE SW MTNS...HOWEVER THIS IS LESS LIKELY
CONSIDERING THE RIDGE THAT SHOULD BE IN PLACE. AN UPPER LEVEL LOW
MOVING THROUGH THE REGION LATE NEXT WEEK WILL BE THE NEXT CHANCE FOR
PRECIPITATION AFTER THIS WEEKENDS STORM. THERE IS STILL VARIATION ON
POSITION AND TIMING...BUT RAIN SHOWERS ARE POSSIBLE AS EARLY AS
THURSDAY AFTERNOON AS THE ASSOCIATED WARM FRONT NOSES INTO
PENNSYLVANIA. THE COLD FRONT WILL MOVE THROUGH THE AREA DURING THE
FIRST PART OF THE WEEKEND BRINGING MORE RAIN. DEPENDING ON THE
SPEED OF THE LOW...PRECIPITATION COULD LINGER INTO SUNDAY.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
A COMPLEX AREA OF LOW PRESSURE OVER THE DELMARVA REGION THIS
AFTERNOON WILL MOVE ONLY SLOWLY EAST THROUGH THE RES OF THE
DAYLIGHT HOURS...KEEPING WEATHER UNSETTLED THROUGH MUCH OF THE
TAF PERIOD. WIDESPREAD MVFR CIGS AND VISBYS /WITH AREAS OF IFR/
IN RAIN WET SNOW WILL PERSIST THROUGH THIS AFTERNOON...WITH
IFR/LIFR CONDS MOST PREVALENT ACROSS THE WRN AND NWRN MTNS...JST
AND BFD.
AS THE DEEP SFC LOW REMAINS NEAR TO THE COAST...WINDS SUSTAINED
BETWEEN 15-25 MPH WITH HIGHER GUSTS WILL BE PREVALENT AT ALL
AIRFIELDS INTO TONIGHT. HIGH CONFIDENCE IN GUSTS AOB 25KTS BETWEEN
18Z TODAY AND 04Z MONDAY.
OUTLOOK...
MON...LOW CIGS RAIN/SNOW ENDING ERN SXNS EARLY BCMG VFR. MVFR/IFR
CIGS WEST BCMG VFR.
TUE...VFR WITH OCNL MVFR PSBL IN SCT SHRA ASSOCD WITH COLD FRONT.
WED-THU...VFR/MVFR WITH CHC OF RAIN.
&&
.HYDROLOGY...
FLOOD WATCH CONTINUES FOR ABOUT EASTERN THIRD OF CWA THROUGH
THIS EVENING. THE CLOSED UPPER LOW IS EXPECTED TO CLOSE TRACK
SLOWUY TO THE EAST AND OFF MID ATLC COAST LATE TODAY AND TONIGHT.
THIS WILL PRODUCE A FEW MORE NWWD BANDS OF MDT TO HEAVY RAIN OVER
SCENT AND EASTERN PENN TODAY.
THE HIGHER AMOUNTS STILL LOOK TO BE FOCUSED ACROSS THE SCENT
MTNS...LOWER SUSQ VALLEY AND ECENT MTNS...AS THE DEFORMATION ZONE
TO THE N/W OF THE UPPER LOW CENTER MOVES TO THE EAST AS WELL. THE
RAIN MAY NOT MOVE OUT ENTIRELY UNTIL MIDNIGHT OR LATER. THUS...THE
WATCH MAY NEED TO BE EXTENDED TO COVER THE PERIOD OF RUNOFF. BUT
HAVE NOT MADE THIS MOVE QUITE YET. LOCALIZED STORM TOTAL AMOUNTS
OF UP TO 2 INCHES ARE LIKELY OVER THE EAST. THIS WILL CAUSE
SIGNIFICANT RISES ON THE SMALL STREAMS AND SOME MAY BE RISING TO
BANKFULL BEFORE NOON. MANY OF THE LARGER WATERWAYS MAY GET TO
THEIR CAUTION STAGES...BUT THESE EFFECTS WOULD BE DELAYED FOR A
PERIOD OR TWO. THE MAINSTEM RIVER IS ALREADY PROGGED TO REACH
CAUTION STAGES AT MANY PLACES WITH CURRENT QPF IN THE HYDRO MODEL.
MMEFS PROBS FOR EXCEEDENCE MAY BE UNDERDONE IN THE SREF
DATA...MAINLY DUE TO THE SHIFTING QPF AREAS/CENTERS AMONGST THE
MEMBERS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR PAZ028-036-037-041-
042-046-049>053-056>059-063>066.
WINTER WEATHER ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR
PAZ042.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...CERU/COLBERT
AVIATION...LAMBERT
HYDROLOGY...LAMBERT
AREA FORECAST DISCUSSION...UPDATED
NWS BLACKSBURG VA
112 PM EDT SUN MAR 30 2014
.SYNOPSIS...
AN UPPER LEVEL LOW WILL SHIFT OFF THE COAST THIS AFTERNOON. HIGH
PRESSURE WILL RETURN TO THE AREA LATE TONIGHT AND MONDAY. A FRONT
MOVES THROUGH BY TUESDAY NIGHT BUT LOOKS DRY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 100 PM EDT SUNDAY...
WILL BE DROPPING THE GOING WINTER WEATHER HEADLINES AS SNOW
SHOWERS HAVE FINALLY DIMINISHED TO ONE SMALLER BAND ALONG THE BLUE
RIDGE THAT SHOULD FADE SHORTLY. TEMPS HAVE ALSO WARMED ENOUGH
OUTSIDE OF THE HIGHER ELEVATIONS TO LIMIT ANY ADDED ACCUMULATION
THE REST OF THE AFTERNOON. WILL ALSO LOWER POPS AND ADJUST TEMPS.
AS OF 1030 AM EDT SUNDAY...
PERSISTENT BANDS OF HEAVY SNOW CONTINUE TO SPILL SOUTH FROM BATH
COUNTY EAST TO AMHERST WITH ELEVATION ALLOWING SNOW TO QUICKLY
ACCUMULATE TO BETTER THAN 6 INCHES IN STRIPS ALONG THE I-64 TO
I-81 CORRIDOR UP NORTH. LATEST RAP AND LOCAL MODEL SOLNS SUGGEST
ANOTHER HOUR OR SO OF ACCUMULATING SNOWFALL IN THESE AREAS BEFORE
THE DEFORMATION AREA FINALLY SHIFTS SE AND WEAKENS. THUS WILL
KEEP THE ADVISORY GOING ACROSS PARTS OF THE SOUTHERN SHENANDOAH
VALLEY WHILE INCLUDING LOCALLY HIGHER TOTALS GIVEN THE HUGE RANGE
ACROSS COUNTIES WITH LITTLE AT LOWER ELEVATIONS. ELSEWHERE SHOULD
BE WARM ENOUGH FOR MOSTLY RAIN FARTHER SOUTH WITH ONLY SOME SNOW
MIXED IN NORTH OF HIGHWAY 460 FOR A WHILE LONGER. PRECIP HAS
TAPERED WEST OF THE NEW RIVER VALLEY SO WILL BE REMOVING COUNTIES
FROM THE WINTER WX ADVISORY THERE WHILE KEEPING THE WARNINGS
GOING INTO SE WVA GIVEN SOME CONTININUING LIGHT SNOWFALL. LITTLE
CHANGE TO GOING WIND HEADLINES WITH THE STRONGEST SPEEDS
CONTINUING ALONG THE SOUTHERN BLUE RIDGE BUT LIKELY TO SHIFT NE AS
SOME BREAKS DEVELOP THIS AFTERNOON UNDER A SECONDARY LOW LEVEL JET
MAX THAT LOOKS TO PIVOT ACROSS BY MID AFTERNOON. BEEFED UP CLOUDS
LONGER PER LATEST VIS PICS WITH TEMPS REMAINING BELOW MOS SO
LOWERED A CAT OR SO ACROSS THE REGION FOR THE AFTERNOON.
AS OF 915 AM EDT SUNDAY...
QUICK UPDATE TO ADD THE HIGHER ELEVATIONS OF ROCKBRIDGE AND
AMHERST TO THE GOING WINTER WEATHER ADVISORY DUE TO HEAVIER SNOW
BANDS ON THE BACK EDGE OF THE DEFORMATION ZONE. EXPECT MOST
ACCUMULATION TO BE NEAR THE BLUE RIDGE PARKWAY WITH LESS THAN AN
INCH ELSEWHERE ACROSS THAT REGION. ALSO BUMPED UP AMOUNTS ACROSS
NORTHERN BATH WHERE HAVE ALREADY SEEN 2-3 INCHES. REMAINDER
UNCHANGED AS EXPECT LESS AND LESS ACCUMULATION WITH SOME SLOW
WARMING DURING THE MORNING HOURS. STRONGER WINDS ALONG THE BLUE
RIDGE MAY BE REALIZED OVER THE NEXT FEW HOURS BUT WILL NEED SOME
CLEARING TO ENHANCE MIXING WHICH MAY NOT HAPPEN IN TIME BUT WILL
CONTINUE THE WARNING FOR NOW.
PREVIOUS DISCUSSION AS OF 720 AM EDT SUNDAY...
RADAR CONTINUES TO SHOW DEFORMATION AXIS PIEDMONT WITH NW FLOW
RAIN AND SNOW SHOWERS OVER THE WEST. RADAR OVERSHOOTING THE SNOW
PAST I-77 AND IN NC MTNS. MODELS AGREE THAT DRYING TAKES PLACE
FROM SW TO NE THROUGH THE MORNING AND WILL SEE SNOW SHOWERS AND
RAIN OUT EAST START TO WANE LATE MORNING INTO MID AFTERNOON. STILL
LOOKS LIKE A GOOD 2-6 INCHES POSSIBLE OF SNOW IN THE HIGHER
ELEVATIONS...AND SOME POCKETS OF 1-3 INCHES IN NARROW CORRIDORS
FROM SE WV INTO THE NW NC MTNS AND NEW RIVER VALLEY.
WIND WILL KEEP THE SNOW MEASURING AN ISSUE...AND OVERALL WINDS
WILL BE GUSTY BUT STRONGEST WINDS WILL ARRIVE AS CLEARING TAKES
PLACE AND STILL LOOKING AFTERNOON FOR MOST. ALREADY HAVE HAD GUSTS
OVER 65 MPH AT BOONE...AND A TREE DOWN IN TODD NC.
NO CHANGES WERE MADE TO THE HEADLINES.
PREVIOUS DISCUSSION ISSUED EARLIER THIS MORNING...
OVERALL...MARCH IS TRYING TO GO OUT LIKE A LION...BUT IT WILL HAVE
TO SETTLE FOR THE DAY BEFORE THE END OF THE MONTH.
RADAR THIS MORNING SHOWS THE DEFORMATION ZONE PRECIP LIFTING NWD
ACROSS THE ALLEGHANY HIGHLANDS SOUTHEAST TOWARD SOUTHSIDE VA. THE
PRECIP OVER THE MOUNTAINS HAS CHANGED TO ALL SNOW...BUT SO FAR
LITTLE ACCUMULATION REPORTS...ALTHOUGH THINK MORE WILL BE COMING IN
AS WE HEAD TOWARD DAYLIGHT HOURS. NICE CYCLONIC FLOW SEEN IN THE
RADAR ECHOES AS WELL...WITH UPSLOPE WELL UNDER WAY OVER THE NC
MTNS...NWD INTO SE WV.
HAVE NOT MADE ANY ADDITIONAL CHANGES TO THE HEADLINES...BUT THE
WINDS WILL BE HIT AND MISS THIS MORNING THANKS TO THE CLOUD COVER.
AS WE HEAD THRU THE DAY...THE UPPER LOW WILL MOVE EAST OF THE
DELMARVA WITH STRONG NVA ARRIVING WHICH HELPS TO MIX OUT THE CLOUDS.
FORECAST MOS GUIDANCE AND BUFKIT SOUNDINGS STILL SUGGEST STRONG
WINDS ESPECIALLY THIS AFTERNOON. SOME AREAS WILL NOT REALLY GET TO
ADVISORY OR WARNING LEVELS BUT GIVEN WET GROUNDS...WIND SPEEDS JUST
BELOW WILL CAUSE SOME PROBLEMS. WHERE THE WARNING IS IN
PLACE...THINK 50 TO 60 MPH GUSTS ARE LIKELY AND FEEL THAT TREES ARE
GOING TO BE BLOWN DOWN. HOPEFULLY...NO DAMAGE TO HOMES OR BUSINESSES
WILL OCCUR. ADVISORY AREAS WILL BE MORE FORTUNATE BUT EXPECT SOME
TREE DOWN REPORTS AS WELL.
THE SNOW WILL ALSO TAPER OFF THIS AFTERNOON AS THE UPPER LOW MOVES
AWAY. STILL LOOKS LIKE ELEVATIONS ABOVE 3000 FT WILL GET AS MUCH AS
6 INCHES WHEN ALL IS SAID AND DONE...ESPECIALLY WRN GREENBRIER.
MOIST/WET GROUND WILL HAVE SOME IMPACT ON STICKING...BUT RATE SHOULD
BE HIGH ENOUGH TO GIVE THE HIGHER VALLEYS IN THE WEST A 1-2 INCH
COATING. THOUGH NO ADVISORY IS IN PLACE FOR SNOW ALONG THE BLUE
RIDGE...THINK LOCATIONS SUCH AS POOR MOUNTAIN...PEAKS OF OTTER AND
APPLE ORCHARD MOUNTAIN COULD SEE 1 TO 3 INCHES OF SNOW.
HIGHS TODAY WILL BE TRICKY GIVEN COLD AIR ADVECTION THIS
MORNING...THEN NEUTRAL ADVECTION THIS AFTERNOON...PLUS LATE MARCH
SUN AND DOWNSLOPE. WENT WITH MID 50S EAST OF THE BLUE RIDGE...TO 40S
WEST...WITH 30S IN THE HIGHEST ELEVATIONS FROM BEECH MTN NC...MOUNT
ROGERS VA AND THE WRN SLOPES OF GREENBRIER COUNTY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
AS OF 329 AM EDT SUNDAY...
THE CLOSED LOW THAT WILL TRACK OVER THE FORECAST AREA TODAY WILL
BECOME AN OCCLUDED LOW OFF THE DELMARVA COAST THIS EVENING. THE
ASSOCIATED PRECIPITATION WITH THIS SYSTEM SHOULD BE EAST OF THE
PIEDMONT BY SUNSET. MEANWHILE...HIGH PRESSURE WILL DRIFT EAST OVER
THE OHIO-TENN VALLEYS TONIGHT. THE PRESSURE GRADIENT BETWEEN THESE
TWO SYSTEMS WILL CONTINUE TO PRODUCE WINDY/GUSTY CONDITIONS INTO THE
EVENING. THE PRESSURE GRADIENT STARTS TO LOOSEN AFTER MIDNIGHT
ALLOWING WINDS TO WEAKEN ACROSS THE FOOTHILLS AND PIEDMONT. WINDY
CONDITIONS WILL REMAIN ACROSS THE MOUNTAINS...PARTICULARLY ALONG THE
BLUE RIDGE INTO THE EARLY MORNING HOURS MONDAY. OVERNIGHT MIXING
WILL KEEP RIDGE TOP TEMPERATURES MILDER THAN THE VALLEYS. MOUNTAIN
VALLEY TEMPERATURES WILL RANGE IN THE M/U20S WHILE RIDGES RANGE
BETWEEN 30F-35F. EVEN THOUGH THE WINDS RELAX IN THE EAST EARLY...NOT
AN IDEAL SITUATION FOR RADIATIONAL COOLING...THEREFORE KEPT
OVERNIGHT TEMPERATURES IN THE 30S.
WHAT A DIFFERENCE A DAY MAKES WITH MONDAYS HIGH TEMPERATURES IN THE
60S ACROSS THE WEST AND U60S-L70S IN THE EAST. RELATIVE HUMIDITIES
WILL DROP INTO THE 20S MONDAY AFTERNOON WHILE NORTHWEST WINDS PEAK
BETWEEN 10-15 MPH. WARMER TUESDAY WITH TEMPERATURES PUSHING 70F
ACROSS THE MOUNTAINS AND WIDESPREAD 70S EAST. HUMIDITY LEVELS
SLIGHTLY HIGHER AROUND 30 PERCENT TUESDAY WITH THE LOW LEVEL FLOW
COMING FROM THE SOUTHWEST. BOTH DAYS LOOK IDEAL FOR PRESCRIBE BURNS
WITH THE STRONGER TRANSPORT WINDS OCCURRING TUESDAY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 1145 AM EDT SATURDAY...
BROAD UPPER RIDGING TO REMAIN IN PLACE UNTIL NEAR THE END OF THE
PERIOD WITH SURFACE HIGH PRESSURE OFF THE SE COAST AND MEAN
TROUGHING ACROSS THE CENTRAL AND SW STATES. WILL SEE A WEAK SURFACE
FRONT PUSH SOUTH OF THE REGION WEDNESDAY AS A WAVE PASSES WELL TO
THE NORTH AND HEIGHTS DIP A BIT. HOWEVER THIS BOUNDARY INITIALLY DRY
WITH ONLY WEAK HIGH PRESSURE TO THE NW WHICH SHOULD DO LITTLE TO
DETER VERY WARM TEMPS FOR MIDWEEK. FRONT LOOKS TO LIFT BACK NORTH
THROUGH THE REGION THURSDAY AS STRONGER LOW PRESSURE PIVOTS TOWARD
THE UPPER MIDWEST. BAND OF DEEPER MOISTURE/LIFT MAY TEND TO SPILL
DOWN THE BAROCLINIC ZONE FROM THE WEST SO BUMPED UP POPS STARTING
THURSDAY MORNING...CONTINUING INTO THURSDAY EVENING WITH MOISTURE
AROUND AND WEAK IMPULSES SLIDING BY. STRONGER COLD FRONT WITH THE
WAVE TO THE WEST WILL APPROACH FRIDAY AND SHOULD PASS ACROSS THE
AREA FRIDAY NIGHT INTO EARLY SATURDAY PER THE FASTER EC. EXPECT PRE-
FRONTAL BAND OF SHRA TO AFFECT MUCH OF THE REGION BY FRIDAY
AFTERNOON WITH SOME ISOLATED TSRA POSSIBLE SOUTH AND SW SO RUNNING
WITH CHANCE TO LOW LIKELY POPS INTO FRIDAY EVENING. BOUNDARY LOOKS
TO GET FAR ENOUGH SE TO ALLOW DRYING ON SATURDAY WITH ONLY SOME
EARLY CLOUDS/-SHRA MAINLY NW AND CLEARING ELSW PENDING LATER RUNS.
GOOD SOUTH TO SW FLOW SHOULD FINALLY BRING TEMPS UP TO SPRING LEVELS
AND ALLOW THEM TO STAY THERE WITH HIGHS MOSTLY 70S EXCEPT COOLING TO
60S SATURDAY BEHIND THE FRONT. LOWS WELL ABOVE FREEZING AND PERHAPS
STAYING ABOVE 50 OUT EAST DURING MIDWEEK.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
AS OF 105 PM EDT SUNDAY...
LAST OF THE PERSISTENT SNOW/RAIN BANDS CONTINUING TO DIMINISH
ALONG THE BLUE RIDGE AND SHOULD DISSIPATE IN THE NEXT HOUR OR TWO
AS THE UPPER LOW SHIFTS FARTHER EAST. THIS SHOULD ALLOW SOME DRY
SLOTTING TO TAKE PLACE FROM SOUTHWEST TO THE NORTHEAST LATER THIS
THIS AFTERNOON AS THE CLOSED LOW MOVES OFF THE MID ATLANTIC
COAST. HOWEVER STRONG NORTHWEST WINDS WILL PERSIST ACROSS THE
REGION INTO THIS EVENING WITH GUSTS TO 40-45 KTS POSSIBLE AROUND
BCB/ROA AND 30-35 KTS IN THE EAST AS WELL AS ACROSS SE WVA. OTRW
IMPROVING CIGS SHOULD TAKE SHAPE WITH BLF REBOUNDING FROM LIFR/IFR
TO MVFR THEN VFR AFTER 00Z/8PM AND MVFR TO VFR AT LWB. BCB MAY
SEEN A COUPLE MORE HOURS OF MVFR AS WELL BEFORE ALL IMPROVE TO VFR
UNDER CLEARING SKIES BY THIS EVENING.
HIGH PRESSURE BUILDS IN OVERNIGHT WITH STRONG WINDS FINALLY
SUBSIDING BUT STILL SOME GUSTS TO 20-25 KTS MOUNTAINS THROUGH THE
OVERNIGHT. THE GRADIENT MAY DECOUPLE ENOUGH TO ALLOW VERY LIGHT
WINDS AT LYH/DAN/LWB BEFORE INCREASING SOME MONDAY MORNING UNDER
LIGHT MIXING. SHOULD BE GOOD FLYING WEATHER ON MONDAY WITH CLEAR
SKIES AND SURFACE NW WINDS AT 5-15 KTS.
EXTENDED AVIATION DISCUSSION...
GENERALLY VFR CONDITIONS MONDAY NIGHT UNTIL LATE WEEK WITH A WARM
FRONT LIFTING THROUGH THE AREA ON THURSDAY PERHAPS RESULTING IN
MVFR CIGS AND A FEW SHOWERS. A STRONGER FRONT ARRIVING FROM THE
WEST BY FRIDAY SHOULD SPELL MORE WIDESPREAD PERIODS OF MVFR IN
SHOWERS HEADING INTO FRIDAY NIGHT.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...HIGH WIND WARNING UNTIL 10 PM EDT THIS EVENING FOR VAZ009-
012>020-022-032-033.
WIND ADVISORY UNTIL 10 PM EDT THIS EVENING FOR VAZ007-010-011-
023-024-034-035-043>047-058-059.
NC...HIGH WIND WARNING UNTIL 10 PM EDT THIS EVENING FOR NCZ001>003-
018-019.
WIND ADVISORY UNTIL 10 PM EDT THIS EVENING FOR NCZ004>006-020.
WV...WIND ADVISORY UNTIL 10 PM EDT THIS EVENING FOR WVZ042>045.
&&
$$
SYNOPSIS...NF/WP
NEAR TERM...JH/WP
SHORT TERM...RCS
LONG TERM...JH
AVIATION...JH/MBS/RAB/WP
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND MONDAY
ISSUED AT 301 PM CDT SUN MAR 30 2014
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW SURFACE HIGH
PRESSURE EXTENDING FROM THE LOUISIANA COAST TO NORTHERN LAKE HURON
EARLY THIS AFTERNOON. TEMPERATURES HAVE BEEN SLOW TO WARM SO FAR
TODAY WITH READINGS RANGING FROM THE UPPER 30S AT STURGEON BAY AND
MANITOWOC TO THE MIDDLE 50S AT WISCONSIN RAPIDS. MID AND HIGH CLOUDS
CONTINUE TO STREAM ACROSS NORTHERN WISCONSIN AHEAD OF A SHORTWAVE
MOVING ACROSS THE ROCKIES. NO SIGNS OF GULF MOISTURE ACROSS THE
PLAINS JUST YET DESPITE PREVAILING SOUTHERLY FLOW. DEWPOINTS REMAIN
IN THE UPPER 30S INTO CENTRAL TEXAS. THE MAIN FORECAST CONCERNS
INCLUDE TEMPS TONIGHT AND CHANCES OF PRECIP ON MONDAY.
TONIGHT...LOW PRESSURE WILL EMERGE INTO THE CENTRAL PLAINS WHILE A
SURFACE WARM FRONT WILL DEVELOP OVER CENTRAL OR SOUTHERN WISCONSIN.
AS HEIGHT FALLS OCCUR OVER THE PLAINS...RETURN FLOW AND 850MB THETAE
ADVECTION WILL BE RAMPING UP OVER THE WESTERN GREAT LAKES. BUT THE AIR
ACROSS THE CENTRAL PLAINS IS SO DRY THAT PRECIP CHANCES REMAIN TOO
LOW TO INCLUDE IN THE FORECAST. SHOULD SEE A GRADUAL INCREASE IN
MID AND HIGH CLOUDS HOWEVER. WITH WINDS SHIFTING TO THE SOUTHEAST
NORTH OF THE WARM FRONT...SHOULD MAINTAIN DRY LOW LEVEL AIRMASS
ENOUGH TO LIMIT THE THREAT OF FREEZING DRIZZLE OR FOG. TEMPS TO
FALL INTO THE UPPER 20S OVER NE WISCONSIN TO THE UPPER 30S SOUTH.
MONDAY...A STRONG SURFACE LOW WILL HEAD TOWARDS THE NORTHERN
MISSISSIPPI VALLEY BY LATE IN THE AFTERNOON. MID AND HIGH CLOUDS
WILL BE THICKENING AND LOWERING OVER THE COURSE OF THE DAY...BUT DRY
AIR IN THE LOW LEVELS WILL BE HOLDING OFF PRECIP CHANCES FOR MUCH OF
THE DAY. THINK PRECIP CHANCES WILL IMPROVE BY MID TO LATE AFTERNOON
ACROSS THE FORECAST AREA...BUT UNSURE HOW PRECIP WILL EVOLVE. EVEN
THOUGH MODELS POINT TOWARDS BETTER CHANCES ACROSS NORTHERN
WISCONSIN...THINK INCREASING MOISTURE TRANSPORT ALOFT AND THE
ARRIVAL OF A 700MB THETAE AXIS/EDGE OF DRY SLOT COULD LEAD TO A
BROKEN BAND OF LIGHT SHOWERS AND SPRINKLES PUSHING ACROSS CENTRAL
AND NORTH-CENTRAL WISCONSIN MID TO LATE AFTERNOON. MODIFIED POPS A
BIT TO REFLECT THIS SCENARIO...BUT STILL KEPT POPS MAINLY IN THE
CHANCE RANGE DUE TO CONCERNS OF DRY AIR IN THE LOW LEVELS. WITH THE
WARM FRONT NOW EXPECTED TO STALL OVER CENTRAL WISCONSIN...TEMPS MAY
NOT BE THAT MUCH DIFFERENT THAN TODAY...PERHAPS A COUPLE DEGREES
WARMER.
.LONG TERM...MONDAY NIGHT THROUGH SUNDAY
ISSUED AT 301 PM CDT SUN MAR 30 2014
THE SHORTWAVE TROUGH WILL EXIT THE NORTHERN GREAT
LAKES EARLY TUESDAY WITH COLDER AND DRIER AIR ARRIVING AT THE
SURFACE. THE RAIN WILL CHANGE TO SNOW SHOWERS WITH AN INCH OR SO
POSSIBLE IN THE NORTH. THEN A FLAT UPPER RIDGE ARRIVES WEDNESDAY
AND THURSDAY WITH COLD HIGH PRESSURE CENTERED TO OUR NORTH. SO DRY
AND SLIGHTLY COLDER THAN NORMAL FOR THIS TIME OF THE YEAR.
THE NEXT SYSTEM FOR THURSDAY NIGHT AND FRIDAY IS NOW OVER THE
CENTRAL PACIFIC SO WE WON/T HAVE TOO MUCH CONFIDENCE IN THE MODEL
SOLUTIONS FOR A FEW MORE DAYS. IT DOES LOOK INTERESTING WITH ARCTIC
HIGH PRESSURE TO THE NORTH AND EAST AND STRONG UPPER SYSTEM
APPROACHING FROM THE SOUTHWEST. THE ARCTIC HIGH WILL DELIVER LOW
LEVEL COLD DRY AIR SO SURFACE TEMPERATURES WILL LIKELY BE BELOW
FREEZING BUT ABOVE FREEZING AIR AROUND 850MB COULD MAKE FOR A MIXTURE
OF SNOW...SLEET OR FREEZING RAIN.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1222 PM CDT SUN MAR 30 2014
OVER THE NEXT 24 HOURS...A WARM FRONT WILL STALL OVER
CENTRAL WISCONSIN AS LOW PRESSURE MOVES ACROSS THE CENTRAL PLAINS.
AHEAD OF THE LOW...MID AND HIGH CLOUDS WILL BE PASSING OVERHEAD
ACROSS THE REGION. DRY LOW LEVEL AIR FROM THE CENTRAL PLAINS WILL
KEEP PRECIPITATION TO THE WEST OVER THE PERIOD...BUT A TIGHTENING
PRESSURE GRADIENT WILL LEAD TO THE DEVELOPMENT OF LLWS OVER MUCH OF
THE REGION TONIGHT INTO MONDAY MORNING. OTHERWISE...ANTICIPATE VFR
CONDITIONS TO PREVAIL THROUGH MIDDAY MONDAY...BEFORE CIGS LOWER
MONDAY AFTERNOON AND EVENING.
&&
.HYDROLOGY...
ISSUED AT 301 PM CDT SUN MAR 30 2014
WARMER TEMPERATURES...MILDER WEATHER WILL PRODUCE MELTING SNOW AND
ICE AND RESULT IN AN INCREASED CHANCE OF LOCAL FLOODING EARLY
THIS WEEK. THE SNOW IS VERY DEEP IN THE NORTH AND SHOULD BE ABLE
TO ABSORB RAINFALL WITHOUT FULLY MELTING. HOWEVER...PLACES WITH
JUST A FEW INCHES LEFT ON THE GROUND MAY HAVE MOST OF THE SNOW
MELT...WHICH MAY CAUSE RIVERS AND STREAMS TO RISE. THERE IS ALSO A
CHANCE OF ICE JAMS AS RIVER ICE BREAKS UP. A HYDROLOGICAL OUTLOOK
IS IN EFFECT.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......MPC
HYDROLOGY......RDM
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1238 PM CDT SUN MAR 30 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 319 AM CDT SUN MAR 30 2014
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A DEEP TROUGH SOUTH OF THE GULF OF ALASKA...A VIGOROUS
SHORTWAVE TROUGH COMING INTO CENTRAL CALIFORNIA...AND A RIDGE AXIS
FROM TEXAS INTO THE FORECAST AREA. PROFILER AND VAD WIND DATA SHOWED
A CORRIDOR OF SOUTHWESTERLY 40-55 KT WINDS AT 925MB JUST TO THE WEST
OF THE RIDGE AXIS. THESE WINDS ARE PROPELLING WARMER AIR THAT WAS
OBSERVED OVER THE PLAINS YESTERDAY TOWARDS THE FORECAST AREA. ITS
WORTH NOTING HIGHS YESTERDAY WERE IN THE 60S TO LOW 70S FROM WESTERN
NORTH DAKOTA INTO OKLAHOMA...ASSOCIATED WITH 925MB TEMPS OF 10 TO
20C. CLOUD COVER MOSTLY OF THE SCATTERED CIRRUS VARIETY...REFLECTIVE
OF UPPER LEVEL MOISTURE STREAMING FROM THE PACIFIC ON WATER VAPOR.
AIRMASS ACROSS MUCH OF THE PLAINS AND THE FORECAST AREA VERY DRY PER
00Z SOUNDINGS...NOTED TOO FROM PRECIPITABLE WATER VALUES BETWEEN 0.2-
0.3 INCHES. AT THE SURFACE...THE SURFACE RIDGE THAT WAS OVER THE
AREA YESTERDAY HAS SHIFTED EAST TO OVER LAKE MICHIGAN...WHILE
PRESSURES ARE FALLING ALONG THE LEE OF THE ROCKIES. THE SURFACE
RIDGE HAS PUSHED ANY MEANINGFUL SURFACE MOISTURE...DEWPOINTS AT OR
ABOVE 40F...DOWN TO THE GULF OF MEXICO COAST.
SYNOPTICALLY...THE UPPER RIDGING PRESENT OVER THE FORECAST AREA
LOOKS TO PERSIST THROUGH TONIGHT...WITH A SHIFT TO THE EAST AFTER
MIDNIGHT. THE PUSH EAST TO THE RIDGE IS CAUSED BY THE VIGOROUS
SHORTWAVE LIFTING INTO THE FAR NORTHEAST COLORADO AREA BY 12Z
MONDAY. ITS ALSO WORTH NOTING THAT THE SHORTWAVE BECOMES NEGATIVELY
TILTED.
WITH THE FORECAST AREA PROGGED TO BE IN THE WARM SECTOR OF A
DEEPENING LOW COMING OUT OF COLORADO AND INTO CENTRAL NEBRASKA BY
12Z MONDAY...MUCH OF THE FORECAST CONCERN IS ON TEMPERATURES. 925MB
TEMPS ARE PROGGED TO CONTINUE TO CLIMB THROUGH THE DAY ON A BREEZY
SOUTH TO SOUTHWEST WIND...RISING FROM 1 TO 5C AT 12Z TO 9 TO 13C BY
00Z. THESE READINGS HOLD NEARLY STEADY FOR TONIGHT DUE TO PERSISTENT
25-35 KT SOUTH WINDS. COMBINATION OF THE AFOREMENTIONED WARM
ADVECTION AND SUNSHINE SHOULD EASILY PUSH HIGHS INTO THE 60S ALONG
AND SOUTHWEST OF I-94. NORTH OF I-94...SNOW PACK AND COOLER 925MB
TEMPS WILL HOLD HIGHS BACK INTO THE 50S. THE MIXING TODAY TOO WILL
BE LIMITED A LITTLE DUE TO SCT-BKN CIRRUS EMANATING FROM NEBRASKA
AREA CURRENTLY. WITH A LOW LEVEL JET IN PLACE TONIGHT...MOST
LOCATIONS SHOULD ONLY SEE LOWS IN THE 40S. THERE ARE INDICATIONS THE
TYPICAL COLD SPOTS MIGHT DECOUPLE OR AT LEAST SEE LIGHTER
WINDS...ALLOWING TEMPERATURES THERE TO DIP INTO THE UPPER 30S.
PRECIPITATION-WISE...PLENTIFUL DRY AIR IN PLACE AS SEEN AT 00Z LAST
EVENING WILL KEEP CONDITIONS DRY THROUGH THIS EVENING. AFTER
MIDNIGHT...THERE IS GOOD AGREEMENT AMONG MODELS FOR A WARM CONVEYOR
BELT OF PRECIPITATION TO DEVELOP OVER EASTERN NEBRASKA AND WESTERN
IOWA. MUCH OF THIS PRECIPITATION CORRELATES WITH ISENTROPIC LIFT ON
THE 305-310K SURFACES...OR AT PRESSURES ABOVE 700MB. IN ANY
EVENT...AT LEAST THROUGH TONIGHT...THE FORECAST AREA STAYS DRY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 319 AM CDT SUN MAR 30 2014
MUCH OF THE FOCUS IS ON THE MONDAY THROUGH TUESDAY PERIOD. IMPACTS
DESCRIBED BELOW...
SYNOPTICALLY...ATTENTION IS COMPLETELY ON THE VIGOROUS SHORTWAVE
TROUGH APPROACHING THE CENTRAL CALIFORNIA COAST. MODELS CONTINUE TO
CONVERGE ON A COMMON SOLUTION FOR HANDLING THIS NEGATIVE TILT
TROUGH...THOUGH THERE IS SOME SLIGHT TIMING SPREAD. MODEL CONSENSUS
SHOWS THE TROUGH LIFTING INTO SOUTHWEST MN BY 00Z TUESDAY...
NORTHWEST WI BY 12Z TUESDAY AND INTO ONTARIO BY 00Z WEDNESDAY. THE
NAM REMAINS THE FASTEST OF THE CONSENSUS AND SEEMS A LITTLE
SUSPICIOUS...SEEING THAT THE ECMWF HAS BEEN TRENDING SLOWER OVER THE
PAST FEW DAYS. GIVEN THE VIGOROUS NATURE OF THE SHORTWAVE...WOULD
SEEM A SLOWER AND DEEPER ROUTE WOULD BE THE WAY TO GO. REGARDING
THE SURFACE LOW...FOLLOWING THE SAME PREMISES...BELIEVE THE
SLOWER...DEEPER MORE WRAPPED SYSTEM PRESENTED BY THE
CANADIAN/UKMET/ECMWF IS MORE LIKELY COMPARED TO THE NAM AND EVEN
GFS. WPC HAS ALSO FAVORED THE SAME MODELS.
PRECIPITATION-WISE...THE WARM CONVEYOR BELT DEVELOPING OFF TO OUR
WEST LOOKS LIKELY TO MOVE INTO WESTERN PORTIONS OF THE FORECAST AREA
MONDAY MORNING. HARD TO SAY IF IT IS GOING TO PROGRESS INTO
WISCONSIN PRIOR TO 18Z SEEING THE DRIER NAM/ECMWF LOOK. THEREFORE
HAVE ONLY KEPT 20-40 PERCENT CHANCES 15-18Z. FOR THE AFTERNOON...
THERE ARE SIGNS THAT THE WARM CONVEYOR PRECIPITATION MAY FALL APART
AS IT MOVES INTO WISCONSIN...OR AT LEAST SHIFT NORTH INTO NORTHERN
WISCONSIN....ESPECIALLY IN THE CANADIAN MODELS. GFS 305-310K
ISENTROPIC LIFT PROGS SUGGEST THE SAME. THEREFORE...HAVE KEPT
PRECIPITATION CHANCES MOSTLY IN THE 20-50 PERCENT RANGE OUTSIDE
OF TAYLOR COUNTY WHERE PRECIPITATION IS MOST LIKELY. FOCUS THEN
SHIFTS WEST ON WHETHER SHOWERS OR STORMS CAN FIRE ALONG A COLD
FRONT / DRY LINE. THE GFS/CANADIAN/ECMWF/UKMET ALL INITIATE A SCT-
BKN LINE OF SHOWERS NEAR I-35 TOWARDS 00Z. HOWEVER...THERE ARE TWO
HUGE CONCERNS FOR THIS BEING A LINE OF SURFACE BASED CONVECTION...
FIRST IS A FAIRLY STOUT CAP AROUND 700MB...SECOND ARE SURFACE
DEWPOINTS WHICH MODELS TRY TO JUMP INTO THE LOW 50S. THE DEWPOINTS
SEEM WAY OVERDONE. NOW CANT RULE OUT THE LINE OF SHOWERS FORMING
MORE ABOVE THE CAP GIVEN FORCING FROM THE LEFT EXIT REGION ALONG
WITH DPVA WITH THE TROUGH. SINCE THERE IS NO CAPE ABOVE THE CAP
AND CONCERNED PRECIPITATION MAY NOT FORM AT ALL...REMOVED THE
THUNDER CHANCE. THIS SHOULD ALSO REDUCE THE CONCERN OF ANY
POSSIBLE SEVERE WEATHER. IF A LINE DOES FORM...IT LOOKS TO LIFT
NORTHEAST THROUGH THE AREA DURING THE EVENING. PRECIPITATION LOOKS
MORE LIKELY AFTER MIDNIGHT INTO TUESDAY MORNING OVER THE NORTHWEST
HALF OF THE AREA AS THE COLD CONVEYOR BELT WRAPS IN. MOST OF THIS
SHOULD BE A LIGHT SNOW WITH LITTLE ACCUMULATION. THIS SNOW WILL
TAPER OFF TUESDAY AFTERNOON WITH THE DEPARTURE OF THE SYSTEM.
TEMPERATURES...BEING IN THE WARM SECTOR ALL OF MONDAY WITH 9-13C
925MB READINGS...COMBINED WITH A WARMER START...THAT BREAK IN
PRECIPITATION DURING THE AFTERNOON TO ALLOW FOR MIXING AND BREEZY
SOUTH WINDS...HIGHS AGAIN SHOULD CLIMB INTO THE 60S AT MOST
LOCATIONS. SNOWPACK HOLDS TAYLOR DOWN INTO THE 50S. READINGS THEN
TANK MONDAY NIGHT AS THE COLD AIR WRAPS IN SOUTHWEST TO NORTHEAST.
MUCH COOLER HIGHS FOR TUESDAY...THOUGH SOUTHERN AREAS SHOULD CLIMB
INTO THE MID 40S AS THE COLD AIR DEPARTS.
WINDS...SOUTHERLY 925MB WINDS INCREASE THROUGH MONDAY AS THE
NEGATIVE TILT SHORTWAVE TROUGH APPROACHES. BY 21Z...MOST MODELS PROG
THEM AROUND 40 KT WHILE 850MB WINDS APPROACH 50-55 KT...STRONGEST
SOUTH OF I-90. DAYTIME MIXING SHOULD BE ENOUGH TO GIVE GUSTS OF 30-
35 KT...WITH A PRESSURE FALL CROSSING EAU CLAIRE GIVING SOME
ISALLOBARIC HELP. AN ADVISORY MAY BE NEEDED IF NAM/GFS MOMENTUM
TRANSFER PROGS ARE CORRECT...SUGGESTING 35-42 KT GUSTS. WITH THE
COLD SIDE OF THE SYSTEM...925MB WINDS ARE A LITTLE LESS...CLOSER TO
35 KT FOR MONDAY NIGHT INTO TUE MORNING. THESE SHOULD EASILY MIX TO
THE GROUND. MORE UNCERTAINTY EXISTS ON THE NEED FOR THE ADVISORY ON
THE COLD SIDE.
FOR TUESDAY NIGHT AND BEYOND...
NEXT ITEM OF INTEREST IS THE TROUGH CURRENTLY SOUTH OF THE GULF OF
ALASKA WHICH IS PROGGED TO END UP IN THE SOUTHWESTERN U.S. ON
WEDNESDAY. UPPER RIDGING BUILDS DOWNSTREAM AHEAD OF THE TROUGH...BUT
MOSTLY SOUTH OF THE FORECAST AREA. THIS KEEPS A COLDER LOW LEVEL
AIRMASS IN PLACE. MEANWHILE...ISENTROPIC LIFT OF GULF OF MEXICO
MOISTURE DOWNSTREAM OF THE UPPER TROUGH MAY SPREAD SOME
PRECIPITATION INTO SOUTHERN PORTIONS OF THE FORECAST AREA PER 30.00Z
GFS/GFS ENSEMBLES WEDNESDAY AND WEDNESDAY NIGHT. HOWEVER...30.00Z
CANADIAN AND ECMWF KEEP THE PRECIPITATION SOUTH OF THE FORECAST
AREA. HAVE SPLIT THE DIFFERENCE WHICH RESULTS IN MAINLY A DRY
FORECAST NORTH OF I-90 TO SOME 20-50 PERCENT CHANCES SOUTH. THURSDAY
COULD END UP BEING A MOSTLY DRY DAY. CONFIDENCE IS BEGINNING TO
INCREASE FOR PRECIPITATION THURSDAY NIGHT THROUGH FRIDAY. THIS IS
WHEN MODELS ARE IN GOOD AGREEMENT LIFTING THE TROUGH INTO THE
FORECAST AREA. WINTER WEATHER ADVISORIES REMAIN POSSIBLE...MOSTLY
DUE TO ACCUMULATING SNOW. DRIER WEATHER LOOKS TO MOVE IN FOR
SATURDAY AS THE SYSTEM DEPARTS. BELOW NORMAL TEMPERATURES ARE LIKELY
FOR MUCH OF TUESDAY NIGHT AND BEYOND GIVEN THE UPPER FLOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1237 PM CDT SUN MAR 30 2014
THE SURFACE PRESSURE GRADIENT WILL GRADUALLY RELAX AFTER 30.21Z AS
SHORT WAVE TROUGH MOVES EAST INTO ONTARIO. AS IT DOES...THE
SUSTAINED SOUTH WINDS WILL DROP INTO THE 10 TO 20 KNOTS RANGE AND
THE WIND GUSTS IN THE 25 TO 30 KNOT RANGE WILL END. THE WINDS WILL
DROP EVEN FURTHER INTO THE 5 TO 15 KNOT RANGE THIS EVENING AND
REMAIN THERE THROUGH THE REST OF THE NIGHT.
ON MONDAY MORNING...THE PRESSURE GRADIENT WILL ONCE AGAIN START TO
TIGHTEN AS A STRENGHTENING LOW PRESSURE SYSTEM APPROACHES THE
AREA FROM THE CENTRAL PLAINS. IF THE WE DO NOT MIX FAST ENOUGH
DURING THE MORNING...THERE MAY BE A BRIEF PERIOD OF LOW LEVEL WIND
SHEAR.
A SCATTERED TO BROKEN 25K DECK WILL CONTINUE ACROSS THE AREA
THROUGH 31.10Z AND THEN LOWER INTO THE 8 TO 15K RANGE. SHOWERS
WILL MOVE INTO KRST AROUND 31.15Z AND THEN PERSIST THROUGH THE
REMAINDER OF THE MORNING. THERE ARE SOME INDICATIONS THAT A MVFR
DECK MAY MOVE INTO KRST TOWARD 31.18Z. SINCE THIS WAS AT THE END
OF TAF PERIOD...DID NOT INCLUDE THEM AT THIS TIME.
&&
.HYDROLOGY...
ISSUED AT 319 AM CDT SUN MAR 30 2014
BASED ON GAUGE READINGS ALONG THE KICKAPOO FOR THOSE THAT STILL HAVE
FLOOD WARNINGS...CONFIDENCE IS DECREASING THAT THEY WILL MAKE IT TO
FLOOD. READSTOWN HAS STARTED FALLING...WHEN IT SHOULD STILL BE
RISING. IF TRENDS CONTINUE...THE WARNINGS MAY BE CANCELLED.
FOCUS THEN SHIFTS TO THE BLACK...BUFFALO AND TREMPEALEAU RIVERS. THE
WARM UP OCCURRING TODAY AND PERSISTING INTO MONDAY EVENING...
FEATURING HIGHS IN THE 55-65 RANGE AND LOWS IN THE 38-48 RANGE ALONG
WITH BREEZY SOUTH WINDS...WILL HELP RAPIDLY MELT THE SNOW PACK THAT
IS IN PLACE ALONG AND NORTH OF HIGHWAY 10. THIS RUNOFF WILL MAKE
FLOODING A POSSIBILITY DURING THE WEEK. ON A POSITIVE NOTE...THE
PRECIPITATION FROM THE SYSTEM MOVING THROUGH THE AREA MONDAY AND
MONDAY NIGHT CONTINUES TO LOOK LESS AND LESS. AT THIS POINT...RAIN
DOES NOT APPEAR TO BE MUCH OF A FACTOR TO THE RIVERS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FLOOD WATCH FROM LATE MONDAY NIGHT THROUGH THURSDAY MORNING FOR
WIZ029-033-034.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...BOYNE
HYDROLOGY...AJ