Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 09/22/14
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
340 PM MST SAT SEP 20 2014
.UPDATE...UPDATED AVIATION AND FIRE WEATHER DISCUSSIONS.
&&
.SYNOPSIS...
LINGERING MOISTURE ACROSS THE REGION AND LOW PRESSURE APPROACHING
FROM THE WEST WILL KEEP AT LEAST SLIGHT CHANCES FOR SHOWERS AND
THUNDERSTORMS FOR TODAY. DRIER AIR WILL GRADUALLY FILTER
INTO THE REGION SUNDAY AND MONDAY FOR A DECLINE IN STORM CHANCES.
SLIGHT CHANCES FOR SHOWERS AND THUNDERSTORMS WILL BE CONFINED TO THE
HIGHER MOUNTAINS OF SOUTH-CENTRAL ARIZONA DURING THE MIDDLE OF NEXT
WEEK WITH SLIGHTLY ABOVE NORMAL TEMPERATURES. AN APPROACHING
PACIFIC WEATHER SYSTEM LATE NEXT WEEK WILL LEAD TO AN INCREASE IN
STORM CHANCES.
&&
.DISCUSSION...
MODEL THETA-E GRADIENT ALIGNED WELL WITH THE FAVORABLE LOCATIONS OF
HIGHER MOISTURE CONTENT AND GREATER INSTABILITY. THE RAP MLCAPE
VALUES JUST OVER 1500 J/KG ALONG AN AXIS FROM NOGALES TO BULLHEAD
CITY. WESTERN MARICOPA COUNTY...LA PAZ AND NORTHERN YUMA COUNTIES
LOOK TO BE THE FAVORABLE AREAS FOR CONVECTION THIS AFTERNOON AND
EVENING. CAN NOT RULE OUT ISOLATED STORMS SNEAKING IN TO NORTHERN
PINAL COUNTY FROM SOUTH-CENTRAL ARIZONA...AS THE GREATER TUCSON AREA
HAS BEEN INCREASING IN ACTIVITY LATE THIS MORNING. PRECIPITABLE
WATER VALUES HOVERING AROUND 1.5 INCHES ACROSS THE LOWER DESERTS AND
A VERY BROAD DIFLUENT MID-LAYER STRETCHING NORTH-NORTHWEST THROUGH
THE GREAT BASIN ALLOWS FOR CONVECTIVE DEVELOPMENT THIS AFTERNOON AND
EVENING. MOISTURE AND DYNAMICS ARE IN PLACE AND THE POTENTIAL ENERGY
IS THERE...NOW THE CHALLENGE WILL BE FOR A TRIGGER TO PUSH THE
DEVELOPMENT NEEDED FOR THUNDERSTORM DEVELOPMENT.
STORM CHANCES WILL BE ON THE DECLINE THROUGH MONDAY BEFORE COMING TO
A QUIET HOLDING PATTERN THROUGH THE WEEK. MONSOON MOISTURE LOOKS TO
HANG AROUND THIS WEEK BUT MAINLY ACROSS EASTERN ARIZONA. THE UPPER
LEVEL DISTURBANCE IS PROGGED TO MOVE NORTH THROUGH THE GREAT BASIN
BY MONDAY AND WILL ALLOW A WESTERLY FLOW TO SETTLE IN PLACE OVER THE
SOUTHWEST DESERTS AS WELL AS A DRYING TREND. WILL KEEP SLIGHT CHANCE
MENTION IN ZONE 24 FOR THE HIGHER TERRAIN LOCATIONS. TEMPERATURES
WILL HAVE LITTLE DAY TO DAY CHANGE...REMAINING AT OR A FEW DEGREES
ABOVE SEASONAL NORMAL WITH HIGH PRESSURE DOMINATING THE REGION
THROUGH MID WEEK.
THURSDAY THROUGH SATURDAY...ATTENTION THEN TURNS TO A POSSIBLE
SEASONAL TRANSITION SYSTEM FOR LATE WEEK INTO NEXT WEEKEND.
CONFIDENCE IS STILL NOT VERY HIGH ON THE SPECIFICS OF THE SYSTEM BUT
THE 00Z OPERATIONAL MODELS HAVE COME IN CLOSER AGREEMENT THAT A DEEP
PACIFIC TROUGH WILL SLIDE THROUGH CALIFORNIA ON FRIDAY AND POSSIBLY
AS FAR SOUTH AS ARIZONA SOMETIME NEXT WEEKEND. WIDESPREAD SLIGHT
CHANCE POPS ARE IN THE FORECAST FOR FRIDAY. EITHER WAY IT IS FAIRLY
LIKELY THIS LOW WILL USER IN COOLER AND MUCH DRIER AIR...AND
POTENTIALLY END OUR MONSOON SEASON.
&&
.AVIATION...
SOUTH-CENTRAL AND SOUTHWEST ARIZONA INCLUDING KPHX...KIWA...KSDL...
ISOLATED TO WIDELY SCATTERED THUNDERSTORM ACTIVITY WILL PERSIST THIS
AFTERNOON AND EVENING OVER SOUTH-CENTRAL AZ...A FEW STORMS COULD
BRIEFLY IMPACT LOW DESERT TERMINALS WITH GUSTY OUTFLOWS UP TO 40
KT...AND REDUCED VISIBILITY DOWN TO 3SM IN BLDU. EXPECT SCT-BKN
CLOUD DECKS AOA 7000FT TO PERSIST OVERNIGHT TIMES INTO SUNDAY
MORNING. ONCE POTENTIAL FOR OUTFLOW BOUNDARIES DIMINISHES AFTER
04Z...WINDS WILL GENERALLY BE LIGHT...LESS THAN 10KT AND FAVOR THE
EAST SOUTHEAST AT ALL TERMINALS.
SOUTHEAST CALIFORNIA INCLUDING KIPL...AND KBLH...
OTHER THAN A FEW CLOUDS GENERALLY AOA 10KFT...EXPECT MOSTLY CLEAR
SKIES AND LIGHT WINDS OVERNIGHT THROUGH AT LEAST 18Z SUNDAY
AFTERNOON.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
MOISTURE RETREAT DUE TO WESTERLY FLOW WILL KEEP STORM CHANCES
MINIMAL THROUGH THURSDAY AND LIMITED TO THE HIGHER MOUNTAINS OF
SOUTH-CENTRAL ARIZONA. MEANWHILE...TEMPERATURES NUDGE UPWARD A FEW
DEGREES ABOVE NORMAL. HUMIDITIES ON THE LOWER DESERTS DROP BELOW 15
PERCENT THOUGH MAX HUMIDITIES REMAIN FAIR. NO STRONG WINDS ARE
EXPECTED DURING THIS TIME FRAME. ON FRIDAY...A PACIFIC WEATHER
SYSTEM WILL PULL MOISTURE NORTHWARD OVER THE REGION FOR A RETURN OF
STORM CHANCES INTO NEXT WEEKEND...MAINLY EAST OF THE LOWER COLORADO
RIVER VALLEY. IN ADDITION...COOLER TEMPERATURES AND BREEZY TO
LOCALLY WINDY CONDITIONS CAN BE EXPECTED AS WELL.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...DEWEY
AVIATION...MEYERS
FIRE WEATHER...MEYERS/AJ
AREA FORECAST DISCUSSION...UPDATED
NWS PHOENIX AZ
205 PM MST SAT SEP 20 2014
.SYNOPSIS...
LINGERING MOISTURE ACROSS THE REGION AND LOW PRESSURE APPROACHING
FROM THE WEST WILL KEEP AT LEAST SLIGHT CHANCES FOR SHOWERS AND
THUNDERSTORMS FOR TODAY. DRIER AIR WILL GRADUALLY FILTER
INTO THE REGION SUNDAY AND MONDAY FOR A DECLINE IN STORM CHANCES.
SLIGHT CHANCES FOR SHOWERS AND THUNDERSTORMS WILL BE CONFINED TO THE
HIGHER MOUNTAINS OF SOUTH-CENTRAL ARIZONA DURING THE MIDDLE OF NEXT
WEEK WITH SLIGHTLY ABOVE NORMAL TEMPERATURES. AN APPROACHING
PACIFIC WEATHER SYSTEM LATE NEXT WEEK WILL LEAD TO AN INCREASE IN
STORM CHANCES.
&&
.DISCUSSION...
MODEL THETA-E GRADIENT ALIGNED WELL WITH THE FAVORABLE LOCATIONS OF
HIGHER MOISTURE CONTENT AND GREATER INSTABILITY. THE RAP MLCAPE
VALUES JUST OVER 1500 J/KG ALONG AN AXIS FROM NOGALES TO BULLHEAD
CITY. WESTERN MARICOPA COUNTY...LA PAZ AND NORTHERN YUMA COUNTIES
LOOK TO BE THE FAVORABLE AREAS FOR CONVECTION THIS AFTERNOON AND
EVENING. CAN NOT RULE OUT ISOLATED STORMS SNEAKING IN TO NORTHERN
PINAL COUNTY FROM SOUTH-CENTRAL ARIZONA...AS THE GREATER TUCSON AREA
HAS BEEN INCREASING IN ACTIVITY LATE THIS MORNING. PRECIPITABLE
WATER VALUES HOVERING AROUND 1.5 INCHES ACROSS THE LOWER DESERTS AND
A VERY BROAD DIFLUENT MID-LAYER STRETCHING NORTH-NORTHWEST THROUGH
THE GREAT BASIN ALLOWS FOR CONVECTIVE DEVELOPMENT THIS AFTERNOON AND
EVENING. MOISTURE AND DYNAMICS ARE IN PLACE AND THE POTENTIAL ENERGY
IS THERE...NOW THE CHALLENGE WILL BE FOR A TRIGGER TO PUSH THE
DEVELOPMENT NEEDED FOR THUNDERSTORM DEVELOPMENT.
STORM CHANCES WILL BE ON THE DECLINE THROUGH MONDAY BEFORE COMING TO
A QUIET HOLDING PATTERN THROUGH THE WEEK. MONSOON MOISTURE LOOKS TO
HANG AROUND THIS WEEK BUT MAINLY ACROSS EASTERN ARIZONA. THE UPPER
LEVEL DISTURBANCE IS PROGGED TO MOVE NORTH THROUGH THE GREAT BASIN
BY MONDAY AND WILL ALLOW A WESTERLY FLOW TO SETTLE IN PLACE OVER THE
SOUTHWEST DESERTS AS WELL AS A DRYING TREND. WILL KEEP SLIGHT CHANCE
MENTION IN ZONE 24 FOR THE HIGHER TERRAIN LOCATIONS. TEMPERATURES
WILL HAVE LITTLE DAY TO DAY CHANGE...REMAINING AT OR A FEW DEGREES
ABOVE SEASONAL NORMAL WITH HIGH PRESSURE DOMINATING THE REGION
THROUGH MID WEEK.
THURSDAY THROUGH SATURDAY...ATTENTION THEN TURNS TO A POSSIBLE
SEASONAL TRANSITION SYSTEM FOR LATE WEEK INTO NEXT WEEKEND.
CONFIDENCE IS STILL NOT VERY HIGH ON THE SPECIFICS OF THE SYSTEM BUT
THE 00Z OPERATIONAL MODELS HAVE COME IN CLOSER AGREEMENT THAT A DEEP
PACIFIC TROUGH WILL SLIDE THROUGH CALIFORNIA ON FRIDAY AND POSSIBLY
AS FAR SOUTH AS ARIZONA SOMETIME NEXT WEEKEND. WIDESPREAD SLIGHT
CHANCE POPS ARE IN THE FORECAST FOR FRIDAY. EITHER WAY IT IS FAIRLY
LIKELY THIS LOW WILL USER IN COOLER AND MUCH DRIER AIR...AND
POTENTIALLY END OUR MONSOON SEASON.
&&
.AVIATION...
SOUTH-CENTRAL AND SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA
INCLUDING KPHX...KIWA...KSDL...KIPL...AND KBLH...
AN UPPER LOW CENTERED OFF THE COAST OF SOUTHERN CALIFORNIA WILL PULL
MONSOON MOISTURE NORTHWARD TODAY FOR SCT-BKN080-100 WITH SCATTERED
SHOWERS AND THUNDERSTORMS OVER THE HIGHER TERRAIN NORTH...EAST...AND
SOUTH...OF THE PHOENIX AREA AND ISOLATED ELSEWHERE. ONSET OF SHOWERS
POSSIBLE BEFORE 18Z. CONFIDENCE TOO LOW AN ANY GIVEN TAF SITE TO
INSERT TEMPO SHWRS/TSTMS.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
MOISTURE RETREAT DUE TO WESTERLY FLOW WILL KEEP STORM CHANCES
MINIMAL THROUGH THURSDAY AND LIMITED TO THE HIGHER MOUNTAINS OF
SOUTH-CENTRAL ARIZONA. MEANWHILE...TEMPERATURES NUDGE UPWARD A FEW
DEGREES ABOVE NORMAL. HUMIDITIES ON THE LOWER DESERTS DROP BELOW 15
PERCENT THOUGH MAX HUMIDITIES REMAIN FAIR. NO STRONG WINDS ARE
EXPECTED DURING THIS TIME FRAME. ON FRIDAY...A PACIFIC WEATHER
SYSTEM WILL PULL MOISTURE NORTHWARD OVER THE REGION FOR A RETURN OF
STORM CHANCES...MAINLY EAST OF THE LOWER COLORADO RIVER VALLEY. IN
ADDITION...COOLER TEMPERATURES AND BREEZY TO LOCALLY WINDY
CONDITIONS CAN BE EXPECTED AS WELL.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...DEWEY
AVIATION...AJ
FIRE WEATHER...AJ
AREA FORECAST DISCUSSION...UPDATED
NWS RENO NV
802 PM PDT SUN SEP 21 2014
.UPDATE...
SATELLITE IMAGERY SHOWS UPPER LOW OVER WEST CENTRAL NV LIFTING NE
TOWARD THE NORTH CENTRAL PART OF THE STATE. THIS IS IN LINE WITH
CURRENT MODEL GUIDANCE. CONVECTION OVER THE FAR EASTERN PARTS OF
THE CWA IS DISSIPATING...BUT THIS CONVECTION DID PRODUCE SOME
HEAVIER RAINS OVER ISOLATED AREAS TODAY RESULTING IN TWO REPORTS
OF WATER AND DEBRIS OVER STATE HIGHWAYS IN SOUTHEAST CHURCHILL
COUNTY. THE HRRR STILL SHOWS CONVECTION DEVELOPING OVER THE FAR
NRN CWA LATER THIS EVENING ASSOCIATED WITH A WEAK VORTICITY LOBE
ROTATING AROUND THE UPPER LOW AND A LITTLE LINGERING CONVECTION
OVER THE FAR EASTERN CWA. WITH THIS IN MIND HAVE DECREASED POPS
FOR THE FAR WEST AND SOUTH BUT LEFT SOME SMALL POPS IN OVER THE
FAR NORTH AND EAST THROUGH LATE EVENING. AS UPPER LOW EXITS LATE
TONIGHT DRIER CONDITIONS SHOULD RETURN FOR MONDAY.
ATTENTION TURNS TO THE SMOKE FROM THE KING FIRE THAT HAS MOVED
BACK INTO THE WESTERN PART OF NEVADA AND NORTHEAST CALIFORNIA. THE
SMOKE WAS A LITTLE THICKER LATE THIS AFTERNOON. THE THINNING OF
THE SMOKE IS LIKELY A RESPONSE TO LESS FIRE ACTIVITY AND LIGHTER
WINDS THIS EVENING. SMOKE FORECASTING CAN BE SOMEWHAT DIFFICULT AS
IT RELIES LARGELY ON THE INTENSITY OF THE FIRE. EVEN THOUGH THE
SMOKE HAS THINNED WE COULD SEE A RESURGENCE LATE TONIGHT AS THE
ATMOSPHERE BECOMES MORE STABLE...OR IT COULD THIN MORE. WILL LEAVE
THE DENSE SMOKE ADVISORY IN PLACE AS WINDS MONDAY SHOULD BECOME
MORE WESTERLY THROUGH THE DAY AND DRIVE ANY SMOKE GENERATED BACK
THIS DIRECTION. IT IS POSSIBLE THAT STRONGER WINDS LATER IN THE
WEEK WILL RESULT IN EVEN MORE SMOKE IN THE TAHOE BASIN AND WRN
NEVADA...BUT THIS REMAINS A BIT UNCERTAIN AT THIS TIME. 20
&&
.PREVIOUS DISCUSSION... /ISSUED 306 PM PDT SUN SEP 21 2014/
SYNOPSIS...
SOUTHWEST FLOW AND BUILDING HIGH PRESSURE WILL THEN BRING WARMER AND
DRIER CONDITIONS TO THE REGION THROUGH THE MIDDLE OF THE WEEK, ALONG
WITH SMOKE TO THE REGION FROM THE ONGOING KING FIRE. STRONGER
LOW PRESSURE BRINGS INCREASING WINDS AND COOLER TEMPERATURES WITH
POSSIBLE RAIN LATER IN THE WEEK.
SHORT TERM...
LIGHT RAINFALL TODAY THROUGH THE SIERRA AND UP THROUGH FAR NORTHWEST
NEVADA AS THE LOW PRESSURE PIVOTED THROUGH THE AREA. THE AREA THAT
RECEIVED THE HIGHEST RAINFALL WAS IN EASTERN PERSHING AND CHURCHILL
COUNTIES LAST NIGHT WHERE UP TO 0.50" FELL. OTHERWISE, ONLY LIGHT
RAIN WAS REPORTED FOR OTHER AREAS.
A FEW ISOLATED SHOWERS AND THUNDERSTORMS HAVE DEVELOPED IN WESTERN
NEVADA THIS AFTERNOON. ONE SHOWER THAT MOVED INTO FERNLEY EARLIER
PRODUCED BRIEF, BUT HEAVY RAINFALL IN THE AREA. THIS GOES TO SHOW
THAT THE MOISTURE CONTENT IN THE AIR IS VERY HIGH, WITH EFFICIENT
PRECIPITATION. ISOLATED TO SCATTERED SHOWERS WILL CONTINUE THROUGH
THE EVENING HOURS, THEN TAPER OFF AS LOW PRESSURE MOVES OUT OF THE
REGION.
ABUNDANT CLOUD COVER HAS REMAINED OVER THE REGION ALL DAY, KEEPING
TEMPERATURES A BIT COOLER AND KEEPING THE AIR FROM MIXING. THIS WAS
A BIG FACTOR IN THE SMOKE IN THE TRUCKEE AREA NOT BEING ABLE TO MIX
OUT DUE TO THE LACK OF HEATING. WINDS AT RIDGE LEVEL HOWEVER ARE
SHIFTING TO THE SOUTHWEST AND WILL BRING ADDITIONAL SMOKE INTO TAHOE
BASIN AND RENO-CARSON-MINDEN AREAS AS WELL. A DENSE SMOKE ADVISORY
HAS BEEN ISSUED THROUGH MONDAY AFTERNOON IN ANTICIPATION THAT SMOKE
WILL BECOME WORSE OVER THE NEXT 24 HOURS. SMOKE DENSITY WILL ALSO
DEPEND HIGHLY ON FIRE ACTIVITY OVER THE NEXT FEW DAYS, SO THE DENSE
SMOKE ADVISORY WILL NEED TO BE REEVALUATED EACH AFTERNOON. BUT, WITH
THE SOUTHWEST FLOW EXPECTED TO CONTINUE, SMOKE WILL REMAIN IN THE
FORECAST THROUGH AT LEAST WEDNESDAY.
DRY AND WARM CONDITIONS WILL RETURN TO THE REGION MONDAY AND TUESDAY
AS HIGH PRESSURE BUILDS OVER THE REGION AND SOUTHWEST FLOW RETURNS
ALOFT. EXPECT TEMPERATURES TO INCREASE TO ABOVE NORMAL AGAIN WITH
MID TO UPPER 80S IN WESTERN NEVADA AND 70S IN THE SIERRA. HOON
LONG TERM...WEDNESDAY THROUGH SUNDAY...
A TROUGH OVER THE EAST PACIFIC WILL PROVIDE BREEZY SOUTHWEST WINDS
BY MIDWEEK AHEAD OF A COLD FRONT WHICH WILL PROVIDE COOLER
CONDITIONS AND CHANCES FOR SHOWERS THE SECOND HALF OF THE WEEK. THE
FORECAST CONFIDENCE IN THE EXTENDED IS GOOD FOR WEDNESDAY AND
THURSDAY BEFORE DEGRADING SIGNIFICANTLY OVERNIGHT THURSDAY INTO
FRIDAY DUE TO LARGE DISCREPANCIES IN TIMING THE EJECTION OF THE
UPPER LOW.
FOR WED-THU, AXIS OF THE UPPER TROUGH WILL REMAIN JUST OFF THE WEST
COAST WITH GUSTY WINDS MAINLY CONCENTRATED NORTH OF INTERSTATE 80 AS
THE UPPER LEVEL JET BEGINS TO DROP ACROSS NE CALIFORNIA. STRONGER
WINDS LOOK TO BECOME MORE WIDESPREAD BY THURSDAY AHEAD OF A FRONT AS
THE SURFACE PRESSURE GRADIENT INTENSIFIES AND THE CORE OF 105+ KT
JET CROSSES THE SIERRA. SUSTAINED SW-W WINDS IN THE 15-25 MPH RANGE
ARE POSSIBLE THURSDAY BEFORE SHIFTING NORTHWEST BEHIND THE FRONT
WITH MODELS PUSHING THE FRONT THROUGH OVERNIGHT THURSDAY INTO EARLY
FRIDAY.
COOLER CONDITIONS ARE EXPECTED BEHIND THE FRONT WITH POSSIBLE HIGH
TEMPERATURES ACROSS WESTERN NEVADA ONLY IN THE UPPER 60S TO LOWER
70S AND LOWER 60S ACROSS SIERRA VALLEYS. CONSIDERABLE UNCERTAINTY
EXISTS WITH HOW QUICKLY THE LOW DEPARTS WITH THE GFS BEING MUCH
QUICKER THAN THE EC WHICH LINGERS THE LOW OVER THE REGION THROUGH
NEXT WEEKEND. THE EC WOULD PROVIDE US WITH A COOLER AND WETTER
FORECAST THAN THE WARMER AND DRIER SOLUTION OF THE GFS. LITTLE
CHANGE MADE IN THE FORECAST FOR NEXT WEEKEND AS TRENDS AND ENSEMBLE
RUNS OFFER LITTLE CONFIDENCE TO MAKE MANY ADJUSTMENTS. WILL MAINTAIN
SLIGHT CHANCES FOR SHOWERS AND A SLOWER WARMUP IN THE FORECAST
BEYOND FRIDAY. FUENTES
AVIATION...
THE KING WILDFIRE ALONG THE WEST SLOPES OF THE SIERRA WILL CONTINUE
TO PUSH SMOKE AND HAZE ACROSS THE TERMINALS WITH SURFACE VIS AS LOW
AS 1SM POSSIBLE AT KTVL/KTRK AND LESS THAN 3SM POSSIBLE AT
KCXP/KRNO. OTHERWISE, BRIEF PERIODS OF MVFR CIGS/VIS IN -SHRA ARE
POSSIBLE THROUGH 06Z THIS EVENING BUT CHANCES WILL REMAIN GENERALLY
BELOW 15% ACROSS ALL TERMINALS BEFORE DIMINISHING OVERNIGHT.
THE MAIN STORY INTO MIDWEEK WILL BE ANOTHER APPROACHING LOW PRESSURE
SYSTEM THAT WILL INCREASE SOUTHWESTERLY WINDS AND SMOKE TRANSPORT
INTO KTVL/KTRK/KCXP/KRNO. MOUNTAIN OBSCURATION AND DECREASED SURFACE
VIS WILL BE AN ISSUE AND WILL LIKELY CONTINUE EACH DAY THROUGH AT
LEAST THURSDAY ASSUMING THE KING FIRE REMAINS ACTIVE. FUENTES
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...DENSE SMOKE ADVISORY UNTIL 5 PM PDT MONDAY NVZ002-003.
CA...DENSE SMOKE ADVISORY UNTIL 5 PM PDT MONDAY CAZ072.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
833 AM PDT Sat Sep 20 2014
.Synopsis...
Lingering Sierra showers/t-storms are possible through the
weekend, otherwise, dry & warmer temperatures into early next
week. Cooler and wetter weather arrives middle of next week into
next weekend.
&&
.Discussion...
Satellite imagery shows a cut off 578dm closed low centered just
west of the Channel Islands near Oxnard. This closed circulation
center is sitting directly under the apex of a ridge covering most
of the western US. Water vapor imagery indicates cloud enhancement
is presently occurring over the Motherlode and west slope of Sierra
Nevada this morning. Due to this and other subtle discrepancies, we
have decided to increase coverage and probability of precipitation
throughout the next 12 hours and sent out an update. Near term
model guidance is fairly consistent in bringing in showers/thunderstorms
above 4000 feet in the Sierra. Unfortunately, the HRRR model,
which has quickly become an office favorite for short term
guidance is currently unavailable. The NAM12 model has been
overforecasting convection over the last week, so we are throwing
out that model as it again appears to be overforecasting
the weekends convection. We will continue to keep a close watch on
the development of any convection in the northeastern sector of the
closed low and send out updates as necessary. DRP
.Previous Discussion...
A closed low is currently straddling the central CA coastline. It
will linger over our region today and gradually move northeastward
by tonight. On Sunday, the low will be centered over Nevada with
the backside of the low still impacting the Sierra. Have kept
mention of showers and thunderstorms over the Sierra this weekend.
The WRF model indicates that there will be more showers on the
western side of the crest Sunday. The rest of our CWA will remain
dry with near to above normal temperatures through Tuesday.
Daytime highs will generally be at their warmest today compared to
the rest of the upcoming 7 days. For the short term forecast, max
temperatures will range mid 80s to upper 90s across the valley.
Smoke from the King Fire will continue to impact the Sierra and
foothills into the adjacent Southern Sacramento valley. Hazy
conditions surrounding the smoky area will extend from the
Central Sacramento valley into the Northern San Joaquin valley. On
Sunday, general wind pattern will transition to a weak onshore
flow which should push smoky/hazy conditions eastward.
Short wave ridging behind the closed upper low moves over NorCal
Sunday into Monday for dry weather. Temperatures trend down slightly
over the weekend but remain near to a little above normal into
Monday. JBB
.Extended Discussion (Wednesday through Saturday)
Models remain in good agreement that a stronger trough will
impact the region from Wednesday into the weekend. On Wednesday,
max temperatures will finally dip below normal. In addition, the
chance for showers will start impacting the NorCal coastline
Wednesday morning. Showers should spread over the Coastal range
and nudge into the Sacramento valley by Wednesday afternoon/evening.
The chance of showers will continue to spread eastward and
southward encompassing the majority of our CWA Thursday and
Friday. Daytime highs will be well below normal Thursday into
Saturday ranging 5 to 15 degrees below average. The one
discrepancy to watch in the models is that the GFS is more
progressive in moving the trough eastward out of our region on
Saturday while the ECMWF model has the trough still lingering.
Have kept mention of showers on Saturday, but started to diminish
them across the valley by Saturday night. JBB
&&
.Aviation...
VFR conditions the next 24 hours all TAF sites. MVFR visibility in
smoke possible in the vicinity of the King Fire. Isolated TS also
possible along the higher Sierra 18z today through 06Z Sunday.
North to east winds to 10 knots this morning transitioning to
southerly this afternoon and tonight.
&&
.STO Watches/Warnings/Advisories...
None.
&&
$$
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
940 PM PDT FRI SEP 19 2014
.SYNOPSIS...
A SLOW MOVING TROUGH WILL CONTINUE TO BRING COOLER WEATHER AND A
DEEP MARINE LAYER THROUGH SUNDAY. PATCHY DRIZZLE IS POSSIBLE AGAIN
LATE TONIGHT AND TOMORROW MORNING. A WARMING TREND AND SHALLOWER
MARINE LAYER IS EXPECTED MONDAY THROUGH WEDNESDAY AS HIGH PRESSURE
BUILDS ALOFT.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
THE MARINE LAYER IS A LITTLE DEEPER THAN LAST NIGHT BUT THE STRATUS
COVERAGE IS NOT NEARLY AS WIDESPREAD. ONLY SCATTERED LOW CLOUDS
COVER THE COASTAL WATERS THIS EVENING. STILL EXPECT THE CLOUDS
INCREASE OVERNIGHT AND SPREAD INTO THE VALLEYS...BUT THE ADVANCING
UPPER LOW COULD DISRUPT THE COVERAGE SO IT MAY NOT BE THE UNIFORM
CLOUD DECK THAT WE SAW THIS MORNING. 00Z WRF STILL OUTPUTTING LIGHT
QPF SO THERE MAY BE AREAS OF DRIZZLE AGAIN TOMORROW MORNING.
WATER VAPOR IMAGE SHOWS THE UPPER TROUGH WEST OF PT CONCEPTION THIS
EVENING. IT WILL MOVE EAST TONIGHT...THEN BRIEFLY STALL OVER PT
CONCEPTION SATURDAY BEFORE EJECTING NORTHEAST TOWARD NEVADA SATURDAY
NIGHT AND SUNDAY. THE NAM4 AND CANSAC GENERATE STILL GENERATE SMALL
QPF OVER THE SBD/RIV COUNTY MTNS SATURDAY AFTERNOON WITH THE PASSAGE
OF THE UPPER VORT MAX...SO WILL HOLD ONTO THE SLT CHANCE FOR
SHRA/TSTMS THERE. THE WRFEMS AND HRRR MODELS ARE DRY.
THE LOW MOVES ACROSS NEVADA SUNDAY WITH A SMALL INCREASE IN HTS AND
A FEW DEGREES OF WARMING. GREATER WARMING AND A SHALLOWER MARINE
LAYER MON-WED FROM WEAK RIDGING BUILDING OVER THE SOUTHWEST. THE
GFS SHOWS SOME INCREASE IN PRECIPITABLE WATER WEDNESDAY AS LOW LEVEL
WINDS SHIFT SOUTHERLY...BUT PRECIP IS NOT EXPECTED.
LONG RANGE OUTLOOK LATE NEXT WEEK...THE GFS AND GEM FORECAST A DEEP
TROUGH TO MOVE INTO THE WEST COAST THURSDAY THROUGH SATURDAY WHICH
WOULD BRING COOLING...A DEEPER MARINE LAYER AND GUSTY MTN AND DESERT
WINDS. THE OUTLIER IS THE ECMWF WHICH HOLDS ONTO WEAK RIDGING INTO
THE WEEKEND. THERE IS A 100DM HEIGHT SPREAD BETWEEN THE MODELS WHICH
IS SIGNIFICANT. HAVE TRENDED TOWARD ECMWF SINCE IT HAS BEEN
PERFORMING BETTER THAN THE GFS LATELY...AND HAVE TEMPERED THE
COOLING SOMEWHAT IN THE THU-SAT TIME FRAME.
&&
.AVIATION...
200300Z...LOW CLOUDS WILL MOVE ASHORE THROUGH THE EVENING WITH
BASES 1500-2000 FEET MSL AND SPREAD INTO INLAND VALLEYS OVERNIGHT.
TOPS WILL BE AROUND 3000 FEET. LOCAL VIS 3-5SM IN FAR INLAND
VALLEYS. SCATTER OUT SATURDAY BY 17-19Z. OTHERWISE...SKIES WILL BE
CLEAR AND VIS UNRESTRICTED THROUGH SATURDAY.
ON SATURDAY AFTERNOON IN THE MOUNTAINS THERE WILL BE SOME CUMULUS
BASED AROUND 8000 FEET AND A VERY SMALL CHANCE OF THUNDERSTORMS OVER
THE MOUNTAINS OF RIVERSIDE/SAN BERNARDINO COUNTIES.
&&
.MARINE...
800 PM...NO HAZARDOUS MARINE WEATHER IS EXPECTED THROUGH WEDNESDAY.
&&
.SKYWARN...
SPOTTER ACTIVATION WILL NOT BE NEEDED THIS WEEKEND.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.
&&
$$
PUBLIC...MOEDE
AVIATION/MARINE/BEACHES...MM
AREA FORECAST DISCUSSION
NWS PUEBLO CO
912 PM MDT SUN SEP 21 2014
.UPDATE...
ISSUED AT 856 PM MDT SUN SEP 21 2014
UPDATED TO ADJUST POPS BASED ON THE CURRENT RADAR AND SATELLITE
TRENDS. A LARGE UPPER LEVEL LOW IS SPINNING ACROSS NORTHEAST
NEVADA WITH AN UPPER DISTURBANCE IN THE FLOW LIFTING INTO THE FOUR
CORNERS REGION. AN INCREASE IN THUNDERSTORM ACTIVITY IS NOTED OVER
THE FOUR CORNERS WHICH WILL SPREAD EASTWARD ACROSS THE CONTINENTAL
DIVIDE THROUGH MIDNIGHT. THERE HAVE BEEN SOME LIGHT ECHOES OVER
THE I-25 CORRIDOR AND RATON MESA AREA...BUT NOTHING TOO ORGANIZED
AT THIS TIME. MODELS ARE ALL STILL GENERATING A DECENT BAND OF
SHOWERS AND THUNDERSTORMS LIFTING ACROSS THE AREA OVERNIGHT BUT
FEEL THEY MAY BE OVER DOING THINGS A BIT. FOR NOW HAVE THE HIGHEST
POPS AFTER MIDNIGHT ALONG THE SAN JUAN RANGE...WITH DECREASING
CHANCES AS YOU HEAD EAST INTO THE PLAINS. MODELS HAVE NOT HANDLED
OVERNIGHT CONVECTION WELL THE PAST COUPLE OF NIGHTS...SO WE WILL
SEE HOW THINGS UNFOLD OVER THE NEXT COUPLE OF HOURS. MOZLEY
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 322 PM MDT SUN SEP 21 2014
...HEAVY RAIN POSSIBLE TONIGHT OVER SAN JUAN MOUNTAINS...MARGINAL
SEVERE POSSIBLE ON PLAINS TOMORROW AFTERNOON...
CURRENTLY...
DRIER AIR NOTED OVER PLAINS AS DWPTS OVER FAR EC COLO IN THE
30S...WITH U40S/50S ALONG THE I-25 CORRIDOR. MTNS MAINLY IN THE
40S...WITH MUCH RICHER MOISTURE SW OF THE FCST AREA. AREA OF RAIN
OVER THE CONTDVD EARLIER HAS DISSIPATED...ALTHOUGH CONVECTIVE
SHOWERS WERE DEVELOPING OVER MOST OF THE HIGHER TRRN. A FEW ISOLD
POPS WERE NOTED OVER FAR N EL PASO COUNTY. A FEW CG FLASHES WERE
NOTED WITH THE DEVELOPING CONVECTION...BUT THE BRUNT OF THE INTENSE
LTG ACTIVITY WAS STILL ASSOCIATED WITH THE TROUGH BACK INTO E UTAH.
REST OF THIS AFTERNOON INTO TONIGHT...
MAIN CONCERN THIS PERIOD WILL BE THE MOUNTAINS ALONG THE
CONTDVD...ESPECIALLY THE SAN JUANS. ALL GUIDANCE IS INDICATING BEST
CHANCE OF HEAVY PRECIP WILL BE OVER THE SW FACING SLOPES OF THE SAN
JUANS. MOST OF THE PRGD HEAVY PRECIP WILL BE IN NWS GJT AREA OF
RESPONSIBILITY...BUT SOME OF THIS PRECIP WILL LIKELY MAKE IT OVER
THE DIVIDE. WILL WAIT TIL LATE THIS AFTERNOON TO DECIDE IF A FLASH
FLOOD WATCH IS NEEDED. PROS FOR A WATCH IS MODEL FCST...BUT WE (NWS
PUB) REALLY HAVE NOT RECEIVED HEAVY RAIN OVER THIS REGION SO SOILS
ARE NOT ALL THAT SATURATED.
18Z NAM HAS BEEN SHOWING LOTS OF PRECIP OVER THE GREATER PIKES PEAK
REGION BUT I AM DISCOUNTING THIS DUE TO ITS POOR PERFORMANCE THE
LAST SEVERAL RUNS. RAP GUIDANCE IS QUITE A BIT DRIER. GFS ALSO A LOT
DRIER PIKES PEAK REGION.
OVER THE REST OF THE REGION...I DONT THINK THE PLAINS WILL SEE MUCH
IN THE WAY OF PRECIP THE REST OF THIS AFTERNOON OR TONIGHT. SOME
SHOWERS WILL BE POSSIBLE MAINLY WEST OF THE INTERSTATE...AND ACROSS
N EL PASO COUNTY...BUT THE REST OF THE REGION SHOULD REMAIN DRY.
SOME LOW CLOUDS/FOG WILL BE POSSIBLE ACROSS N EL PASO COUNTY TONIGHT
GIVEN THE MOIST UPSLOPE FLOW.
TOMORROW....
TROUGH ALOFT WILL MOVE ACROSS THE REGION. IT APPEARS NOW THAT THE
SFC TROUGH WILL REMAIN IN COLORADO DURING PRIME HEATING AND WE WILL
LIKELY HAVE A BROKEN LINE OF CONVECTION MOVE ACROSS THE PLAINS
DURING THE AFTERNOON TIME PERIOD. SHEAR LOOKS GOOD BUT CAPE LOOKS
MARGINAL SO SVR THREAT WILL BE MINIMAL. QUITE A FEW CLOUDS MAY BE
OVER THE AREA TOMORROW AND THAT COULD LIMIT HEATING.
MOUNTAINS SHOULD GRADUALLY DRY OUT TOMORROW.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 322 PM MDT SUN SEP 21 2014
MONDAY NIGHT...THE UPPER LOW WILL TRACK E ACROSS WY AND INTO THE
DAKOTAS MON EVE...GRADUALLY BRINGING AN END TO PCPN FROM WEST TO
EAST. CONVECTION IS FORECAST TO BECOME ISOLATED BY MIDNIGHT ACROSS
THE FAR E PLAINS...THEN COME TO AN END EARLY TUE MORN ALONG THE
CO/KS BORDER.
TUESDAY AND WEDNESDAY...A RIDGE OF HIGH PRESSURE BUILDS OVER THE
REGION...ALLOWING FOR PREDOMINANTLY DRY CONDITIONS AND MAX TEMPS IN
THE 80S FOR THE PLAINS...AND 70S FOR THE HIGH VALLEYS. ISOLATED
CONVECTION IS EXPECTED TO LINGER OVER THE FAR SE CORNER AS WELL AS
THE SOUTHERN PORTIONS...INCLUDING THE S SANGRES.
THURSDAY AND FRIDAY...THE UPPER RIDGE BEGINS TO SLIDE TO THE
EAST...AS AN UPPER TROUGH OF LOW PRESSURE BEGINS TO MOVE ONSHORE
ALONG THE WEST COAST. THIS WILL START TO DRAW INCREASING MOISTURE UP
ACROSS THE 4 CORNERS AND INTO WESTERN CO...WHICH IN TURN INCREASES
POPS FOR THE MTS AND WESTERN AREAS FROM THU AFTN ONWARD. A SLIGHT
COOLING TREND IS EXPECTED FROM THU THROUGH FRI...THOUGH TEMPS WILL
STILL BE AT OR SLIGHTLY ABOVE SEASONAL NORMS.
SATURDAY AND SUNDAY...EXTENDED MODELS AGREE ON MOVING THE UPPER
TROUGH AXIS ACROSS THE PAC NW AND GREAT BASIN ON SAT...THROUGH THE
EC IS JUST A BIT SLOWER. THE TROUGH DEEPENS WITH A CLOSED LOW
DEVELOPING BY SUN...WHICH THEN SLOWLY MOVES EAST TOWARD COLORADO.
THE EC HAS THIS LOW OVER NV...WHILE THE GFS HAS THIS LOW EDGING
INTO THE WESTERN HALF OF COLORADO...SO STILL SOME ROOM FOR
NEGOTIATION THERE. END RESULT IS THAT A COOLER PERIOD WITH INCREASED
CLOUDS AND PCPN COVERAGE IS FORECAST FOR THE WEEKEND...AND THE FINER
POINTS AND TIMING WILL HAVE TO BE REVISITED THROUGHOUT THE UPCOMING
WORK WEEK. MOORE
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 322 PM MDT SUN SEP 21 2014
KCOS...MAIN CONCERN IS MOIST UPSLOPE FLOW LATER TONIGHT WHICH WILL
LIKELY BRING SOME LOW CIGS INTO THE TAF SITE. FOR TOMORROW...A LINE
OF BKN CONVECTION SHOULD MOVE ACROSS THE TAF SITE EARLY TOMORROW
AFTERNOON...WITH CLEARING SKIES THEREAFTER.
KPUB...MAINLY VFR NEXT 24H. COULD SEE SOME LOW CIGS LATE
TONIGHT/EARLY TOMORROW MORNING FOR A FEW HOURS.
KALS...COULD SEE SCTD SHOWERS WHICH MAY BRING BRIEF MVFR CONDITIONS
TONIGHT AND EARLY TOMORROW...OTHERWISE VFR.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...MOZLEY
SHORT TERM...HODANISH
LONG TERM...MOORE
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
234 PM MDT SAT SEP 20 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 1224 PM MDT SAT SEP 20 2014
MDLS CONTINUE TO MOISTEN UP THE AIRMASS OVERNIGHT AND SUNDAY. FOR
THIS EVENING...THE LATEST HRRR APPEARS TO KEEP ANY DEVELOPING
THUNDERSTORMS IN THE MOUNTAINS WEST AND SOUTHWEST OF DENVER. THE
AIRMASS REMAINS TOO DRY AND STABLE ELSEWHERE TO SUPPORT ANY DEEP
CONVECTION. THE UPPER RIDGE WILL REMAIN OVER EASTERN COLORADO
TONIGHT...WITH LOW LEVEL ESELY SFC WINDS. THE UPPER LOW WILL BE
OVER SWRN NV SUNDAY MORNING AND WILL MOVE SLOWLY INTO NERN NV BY
00X MONDAY. THE QG ASCENT THROUGH THE PERIOD WILL BE WEAK BUT
PRECIPITABLE WATER VALUES WILL CLIMB BACK OVER AN INCH. WITH THE
COOLER AMS IN PLACE...LIMITED HEATING COUPLED WITH WEAK FORCING
ALOFT SHOULD ALLOW FOR MORE SHOWERS VS THUNDERSTORMS IN THE
FORECAST. WL CONTINUE WITH SCT-LIKELY POPS ACROSS THE MOUNTAINS
AND FOOTHILLS WITH MORE EMPHASIS ON SHOWERS IN THE GRIDS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 230 PM MDT SAT SEP 20 2014
NOT A LOT OF DIFFERENCE IN THE MODEL SOLUTIONS DURING THE PERIOD.
THE UPPER LOW CURRENTLY WEST OF LOS ANGELES IS PREDICTED TO LIFT
TO THE NORTHEAST WITH ITS ASSOCIATED TROUGH PASSING EAST OF THE
STATE TUESDAY MORNING. THE RESULT OF THIS IS A QUANTITATIVELY
MODEST BUT DEEP AND PROLONGED PERIOD OF QUASIGEOSTROPHIC ASCENT
OVER MOST OF THE AREA BEGINNING TONIGHT AND CONTINUING THROUGH
MONDAY NIGHT. THIS ASCENT SHOULD DIMINISH FROM WEST TO EAST DURING
THE DAY TUESDAY AS UPPER LEVEL RIDGING OCCURS OVER THE CENTRAL
ROCKIES. CONSEQUENTLY EVERYONE SHOULD HAVE A SHOT AT SOME
PRECIPITATION AS THIS SYSTEM PASSES BY EARLY IN THE PERIOD WITH
DRIER CONDITIONS EXPECTED AFTER TUESDAY. PRECIPITABLE WATER
VALUES ARE FORECAST TO EXCEED 1.00 INCH WITH THIS SYSTEM AND WITH
MODERATE CAPE VALUES AROUND AT TIMES THE THREAT OF SOME HEAVY
SHOWERS CANNOT BE COMPLETELY RULED OUT IN THE SUNDAY NIGHT THROUGH
TUESDAY MORNING TIME FRAME. AT PRESENT HOWEVER IT IS DIFFICULT TO
SINGLE OUT ANY PARTICULAR AREA FOR ANY ENHANCED FLOODING THREAT.
&&
.AVIATION...(FOR THE TAFS THROUGH 00Z SUNDAY LATE AFTERNOON)
ISSUED AT 1224 PM MDT SAT SEP 20 2014
VFR CIGS/VSBYS THROUGH 06Z...THE AMS DOES MOISTEN UP OVERNIGHT
WITH LCL LOWERING ENOUGH TO PRODUCE ILS APPROACHES WITH OCNL BKN-
OVC CIGS OF 050-060 KFT AGL AFTER 06Z. ISOLD RAIN SHOWERS POSSIBLE
SUNDAY MORNING...WITH BETTER POTENTIAL FOR SHOWERS ALONG THE
FOOTHILLS ON SUNDAY. COOLER AMS WL KEEP THE POTENTIAL FOR TSTMS ON
THE LOW SIDE...WITH A BETTER CHC FOR RAIN SHOWERS SUNDAY AFTN.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...COOPER
LONG TERM...ET
AVIATION...COOPER
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1000 PM EDT SUN SEP 21 2014
.SYNOPSIS...
A PERIOD OF STEADY RAIN WILL AFFECT THE FAR SOUTHEAST NEW ENGLAND
COAST THIS EVENING. OTHERWISE...DRIER AND LESS HUMID WEATHER IS
ON TAP FOR MONDAY AS A DRY COLD FRONT SWEEPS ACROSS THE REGION.
STRONG HIGH PRESSURE WILL BRING SUNNY DAYS AND CLEAR NIGHTS TO THE
REGION FROM TUESDAY THROUGH NEXT WEEKEND WITH A WARMING TREND. WE
COULD APPROACH RECORD WARMTH ON SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
10 PM UPDATE...
A BAND OF STEADY RAIN HAS GENERALLY DIMINISHED ACROSS PORTIONS OF
E MA THIS EVENING AS LOW PRES DEVELOPING OFFSHORE BEGINS TO SHIFT
NE. A FEW MORE SHOWERS ARE LIKELY TO REMAIN FROM THIS BUT JUST
OVER THE NEXT COUPLE OF HOURS. OTHERWISE...HAVE BEEN WATCHING A
DOWNWARD TREND IN CONVECTIVE ACTIVITY IN NY ASSOCIATED WITH THE
COLD FRONT...STILL A BIT OF -SHRA ACTIVITY LEFT...BUT NOT MUCH
CONVECTION. LOOKS LIKE MAINLY WRN MA AND SW NH WILL BE HAVE THIS
RAIN IN THE CARDS BUT GENERALLY AFTER 03Z. AFTER THAT...THE RAPID
ENTRAINMENT OF DRY AIR...LONG SINCE LOSS OF DIURNAL HEATING AND
SHIFT OF BEST DYNAMICS INTO NRN NEW ENGLAND SHOULD ALLOW FOR MOST
OF THESE TO DISSIPATE SUCH THAT VERY LITTLE ACTIVITY...ASIDE FROM
A BRIEF GUST OF WIND AND WIND SHIFT...IS SEEN ELSEWHERE WITH THIS
FROPA.
OTHERWISE...A POCKET OF VERY DENSE FOG HAS DEVELOPED FROM THE N
SHORE OF MA INTO COASTAL MAINE. THIS WILL LIKELY CONTINUE INTO THE
MORNING HOURS. HAVE ISSUED A DENSE FOG ADVISORY FOR THIS AREA.
OTHERWISE...ONLY OTHER LOCATIONS REPORTING UNDER HALF A MILE ARE
ORH AND TAN...BUT FEEL THESE ARE LIKELY MORE COLOCATED WITH THE
AIRPORT.
PREVIOUS DISCUSSION...
MARGINAL INSTABILITY WITH DEEP LOW LEVEL MOISTURE HAS ALLOWED
ISOLATED TO SCATTERED SHOWERS TO CONTINUED TO AFFECT SOUTHERN NEW
ENGLAND. WE SHOULD SEE THIS ACTIVITY DIMINISH EARLY THIS EVENING
WITH THE LOSS OF DAYTIME HEATING.
THE MAIN CONCERN WILL BE THE SURFACE LOW PRESSURE SYSTEM OFF THE MID
ATLANTIC COAST WHICH WILL BE TRACKING NORTHEAST AND PASSING NEAR THE
BENCHMARK THIS EVENING. THE MAIN QUESTION IS HOW FAR NORTHWEST
THE RAIN SHIELD WILL GET. LATEST NEAR TERM GUIDANCE HAS BEEN
TRENDING FURTHER NORTHWEST. THEREFORE...EXPECT A PERIOD OF STEADY
RAIN ACROSS THE CAPE/ISLANDS AND PROBABLY FURTHER NORTHWEST INTO
INTERIOR SOUTHEAST MA/RHODE ISLAND FOR AT LEAST A TIME. IN
FACT...LATEST HRRR SHOWING THE POTENTIAL FOR A BRIEF PERIOD OF
RAIN ACROSS THE NORTHEAST MA COAST INCLUDING BOSTON. NOT SURE IF
IT WILL GET THAT FAR NORTHWEST...BUT ITS CERTAINLY POSSIBLE.
REGARDLESS...THE HEAVIEST RAINFALL WILL OCCUR ACROSS NANTUCKET...
WHERE BETWEEN 0.50 TO PERHAPS UP TO 1 INCH OF RAIN MAY OCCUR.
THE RAIN MAY PERSIST THROUGH MUCH OF THE EVENING ACROSS THE CAPE
AND ISLANDS...BUT SHOULD WIND DOWN NEAR OR JUST AFTER MIDNIGHT.
MEANWHILE...ONCE THE ISOLATED TO SCATTERED DIURNALLY DRIVEN
SCATTERED SHOWERS WIND DOWN EARLY THIS EVENING...THE REST OF THE
REGION WILL MAINLY BE DRY TONIGHT. HOWEVER...A COLD FRONT WILL BE
APPROACHING OUR WESTERN ZONES TOWARD MIDNIGHT. WHILE SHEAR IS QUITE
IMPRESSIVE...VERY LITTLE INSTABILITY WILL BE LEFT. SO WHILE WE MAY
SEE A FEW SPOT SHOWERS AFFECT OUR WESTERN ZONES...THEY WILL BE IN
THE PROCESS OF WEAKENING AND NOT EXPECTING MUCH MORE THAN THAT. LOW
TEMPS WILL ONLY BOTTOM OUT IN THE UPPER 50S AND THE LOWER 60S BY
DAYBREAK MONDAY.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
MONDAY...
A MUCH DRIER AIRMASS WILL WORK INTO THE REGION BEHIND
THE COLD FRONT ON MONDAY. WHILE PARTLY TO MOSTLY SUNNY SKIES ARE
EXPECTED EARLY...MAY SEE A SCATTERED TO BROKEN DECK OF STRATO-
CUMULUS CLOUDS WORK INTO AT LEAST THE INTERIOR BY AFTERNOON. HIGHS
SHOULD MAINLY BE IN THE 60S ACROSS THE INTERIOR...BUT STILL WILL
REACH BETWEEN 70 AND 75 ALONG HE COASTAL PLAIN. GUSTY WEST WINDS
OF 20 TO 30 MPH ARE EXPECTED AS BUFKIT SOUNDINGS SHOWING VERY GOOD
MIXING.
HIGH SURF...GIVEN LARGE SOUTH TO SOUTHEAST SWELL FROM DEPARTING
COASTAL LOW PRESSURE SYSTEM HAVE ISSUED A HIGH SURF ADVISORY FOR THE
SOUTH COAST ON MONDAY. WE ISSUE HIGH SURF PRODUCTS THROUGH THE END
OF SEPTEMBER IF CONDITIONS WARRANT.
MONDAY NIGHT...
HIGH PRESSURE WILL BE BUILDING IN FROM THE WEST. THIS WILL ALLOW
FOR DIMINISHING WINDS AND SKIES TO BECOME MOSTLY CLEAR. LOOKS LIKE
A PRETTY GOOD NIGHT OF RADIATIONAL COOLING...WITH LOWS BOTTOMING OUT
IN THE UPPER 30S TO THE MIDDLE 40S IN MOST LOCALES. THE URBAN HEAT
ISLAND OF BOSTON WILL BE THE MILD SPOT WITH THE LOW BOTTOMING OUT
NEAR 50.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
HIGHLIGHTS...
* HIGH PRESSURE AND DRY WEATHER THROUGH THE PERIOD
* NEAR RECORD WARMTH POSSIBLE NEXT SATURDAY
OVERVIEW...
VERY GOOD AGREEMENT AMONGST MODEL GUIDANCE THE ENTIRE FORECAST
PERIOD. AN UPPER LEVEL TROUGH DEPARTS THE NORTHEAST STATES ON
TUESDAY. THEN...MUCH ADO ABOUT BUILDING HIGH PRESSURE...BOTH AT
THE SURFACE AND ALOFT THE REMAINDER OF THE WEEK. THE UPPER RIDGE
IS VERY STRONG AS IT IS PARKED FROM THE GREAT LAKES TO SOUTHERN
NEW ENGLAND BY NEXT WEEKEND.
DETAILS... TUESDAY WILL FEATURE MOSTLY SUNNY SKIES EXCEPT ONLY
PARTLY SUNNY NW MA AND SW NH CLOSER TO SOME HIGHER 925 MB
HUMIDITY. OTHERWISE...EXPECT SUNNY DAYS AND CLEAR NIGHTS THROUGH
NEXT WEEKEND. HAVE GONE A FEW DEGREES LOWER THAN MODEL CONSENSUS
TEMPERATURE MINIMUMS THROUGH THU DUE TO EXCELLENT RADIATIONAL
COOLING EXPECTED ALONG WITH VERY DRY DEWPOINTS. AS THE CENTER OF
THE UPPER HIGH APPROACHES...AM EXPECTING A DRAMATIC WARMUP FRI
AND ESPECIALLY SAT. THE 12Z ECMWF RUN IS EVEN WARMER THAN THE
PREVIOUS RUN WITH 925 MB TEMPERATURES WARMING FROM +12C TUE...TO
+17C FRI... TO +19C OR +20C ON SAT... WITH WARM TEMPERATURES
LIKELY CONTINUING INTO EARLY THE FOLLOWING WEEK. HAVE GONE SEVERAL
DEGREES ABOVE MODEL CONSENSUS MAXIMUMS FOR NEXT SATURDAY...WITH
HIGHS SOARING TO 80 TO 85 ACROSS INTERIOR SOUTHERN NEW ENGLAND.
RECORDS FOR THAT DAY INCLUDE 85 AT WORCESTER AND 86 AT BOTH BOSTON
AND PROVIDENCE.
LIGHT WINDS ARE EXPECTED FOR THE PERIOD...SO ALTHOUGH IT WILL BE
DRY WE ARE NOT EXPECTING FIRE WEATHER CONCERNS. LOCAL SEA BREEZES
WILL OCCUR...ESPECIALLY FRI THROUGH NEXT SUNDAY. IT SHOULD BE
NOTED THAT THE GFS HAS A HINT OF A POTENTIAL BACKDOOR FRONT/TROUGH
OVER NORTHEAST MA ON SAT BUT THIS WAS NOT ENOUGH TO DETRACT FROM
THE VERY WARM FORECAST...AS YET.
AN UPPER LOW OVER VIRGINIA AND AN ASSOCIATED INVERTED TROUGH IS
LIKELY TO BE CAUSING PRECIPITATION IN THE MID ATLANTIC REGION
MID TO LATE IN THE WORK WEEK THAT TRIES TO WORK ITS WAY NORTHWARD.
THERE IS EXCELLENT MODEL AGREEMENT THAT THIS AREA ONLY GETS AS
FAR NORTHWARD AS OFF THE NJ COAST BY FRI...BEFORE RETREATING
SOUTHWARD AS STRONG HIGH PRESSURE BECOMES ESTABLISHED OVER THE
NORTHEAST ON THE WEEKEND.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH MONDAY NIGHT/...
TONIGHT...LOW TO MODERATE CONFIDENCE. IFR CONDITIONS WITH SOME
LOW IFR CONDITIONS ACROSS FAR SOUTHEAST MA INCLUDING THE CAPE AND
ISLANDS WITH VISIBILITIES BELOW 1/2 MILE AT TIMES IN LOCALLY DENSE
FOG. MOST OF THE REST OF THE REGION WILL BE MVFR CEILINGS...WITH
MANY AREAS BECOMING IFR CEILINGS BETWEEN 02Z AND 06Z. BEST
CONFIDENCE FOR IFR IS FROM ABOUT A JAFFREY-WORCESTER-WILLIMANTIC
LINE EASTWARD. STEADY RAIN WITH EMBEDDED SHOWERS WILL AFFECT THE
FAR SOUTHEAST NEW ENGLAND COAST THIS EVENING. THE RAIN WILL LIKELY
REACH INTO RHODE ISLAND/INTERIOR SOUTHEAST MA FOR A SHORT TIME AND
PERHAPS EVEN INTO NORTHEAST MA.
MONDAY AND MONDAY NIGHT...HIGH CONFIDENCE IN VFR CONDITIONS.
JUST A LOW RISK FOR BRIEF MVFR CIGS ACROSS THE INTERIOR ON MONDAY
AS A DECK OF STRATOCUMULUS CLOUDS MOVES INTO THE REGION.
OTHERWISE...GUSTY WEST TO NORTHWEST WINDS OF 20 TO 25 KNOTS
EXPECTED DURING THE DAY MONDAY.
KBOS TERMINAL...MODERATE CONFIDENCE TONIGHT WITH HIGH CONFIDENCE ON
MONDAY.
KBDL TERMINAL...MODERATE CONFIDENCE TONIGHT WITH HIGH CONFIDENCE ON
MONDAY.
OUTLOOK...TUESDAY THROUGH FRIDAY...
HIGH CONFIDENCE.
TUE...VFR.
WED...VFR
THU...VFR.
FRI...VFR.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
TONIGHT...MODERATE TO HIGH CONFIDENCE. LOW PRESSURE PASSING NEAR
THE BENCHMARK WILL RESULT IN ENOUGH SOUTH TO SOUTHEAST SWELL FOR
SCA SEAS TO DEVELOP ACROSS THE OUTER-WATERS AND WESTERN SOUNDS.
SOUTHEAST WINDS SHOULD BECOME SOUTHWEST TONIGHT AT 10 TO 15 KNOTS
LATER TONIGHT. AREAS OF FOG...SOME LOCALLY DENSE...WILL OCCUR
ACROSS THE WATERS...ESPECIALLY SOUTH OF BOSTON HARBOR.
MONDAY AND MONDAY NIGHT...MODERATE TO HIGH CONFIDENCE. SCA SEAS
ON THE WESTERN SOUNDS AND OUTER-WATERS WILL CONTINUE THROUGH
MONDAY NIGHT. IN ADDITION...A PERIOD OF WEST TO NORTHWEST WIND
GUSTS NEAR 25 KNOTS IS POSSIBLE FOR A TIME ON MONDAY.
THEREFORE...IT IS POSSIBLE WE MAY NEED TO EXPAND SCA FOR A TIME
DURING THE DAY MONDAY INTO SOME OF THE NEARSHORE SOUNDS AND
WATERS. CONFIDENCE NOT QUITE HIGH ENOUGH TO DO THIS RIGHT NOW...
SO WILL DEFER TO THE NEXT SHIFT.
OUTLOOK...TUESDAY THROUGH FRIDAY...
HIGH CONFIDENCE...
TUE AND WED...SEAS NEAR 5 FT MAY LINGER AT TIMES TUE AND WED OVER
THE WATERS S AND E OF NANTUCKET. OTHERWISE WINDS AND SEAS SHOULD
BE BELOW SMALL CRAFT ADVISORY CRITERIA. A NORTHEAST WIND GRADIENT
WILL INCREASE OVER THE SOUTHERN COASTAL WATERS TUE NIGHT INTO WED
AS STRONG HIGH PRESSURE PUSHES INTO NORTHERN NEW ENGLAND. BUT
GUSTS ARE EXPECTED TO ONLY REACH 20 KT.
WED NIGHT THROUGH FRI...QUIET BOATING WEATHER WITH HIGH PRESSURE
DOMINATING THE WEATHER. WINDS AND SEAS BELOW SCA THRESHOLDS.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...HIGH SURF ADVISORY FROM 8 AM TO 5 PM EDT MONDAY FOR MAZ020>024.
DENSE FOG ADVISORY UNTIL 5 AM EDT MONDAY FOR MAZ006-007-014.
NH...NONE.
RI...HIGH SURF ADVISORY FROM 8 AM TO 5 PM EDT MONDAY FOR RIZ006>008.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 AM EDT TUESDAY FOR ANZ235-237.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT TUESDAY FOR ANZ250-254>256.
SMALL CRAFT ADVISORY FROM 6 AM TO 4 PM EDT MONDAY FOR ANZ251.
&&
$$
SYNOPSIS...FRANK/GAF
NEAR TERM...FRANK/DOODY/GAF
SHORT TERM...FRANK
LONG TERM...GAF
AVIATION...FRANK/GAF
MARINE...FRANK/GAF
AREA FORECAST DISCUSSION
NWS TAUNTON MA
707 PM EDT SUN SEP 21 2014
.SYNOPSIS...
A PERIOD OF STEADY RAIN WILL AFFECT THE FAR SOUTHEAST NEW ENGLAND
COAST THIS EVENING. OTHERWISE...DRIER AND LESS HUMID WEATHER IS
ON TAP FOR MONDAY AS A DRY COLD FRONT SWEEPS ACROSS THE REGION.
STRONG HIGH PRESSURE WILL BRING SUNNY DAYS AND CLEAR NIGHTS TO THE
REGION FROM TUESDAY THROUGH NEXT WEEKEND WITH A WARMING TREND. WE
COULD APPROACH RECORD WARMTH ON SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
***A PERIOD OF STEADY RAIN THIS EVENING ACROSS THE SOUTHEAST NEW
ENGLAND COAST***
7 PM UPDATE...SCATTERED DIURNAL-INDUCED SHOWERS HAVE BEGUN TO
DISSIPATE OVER THE INTERIOR WITH SUNDOWN. A FEW HEAVY SHOWERS WERE
STILL IN BOSTON/S SOUTH SHORE HEADING NORTH. AREA OF STEADY RAIN
CONTINUES OVER THE ISLANDS. AREAS OF LOCALLY DENSE FOG HAD
FORMED...AT MARSHFIELD AND FALMOUTH IN SOUTHEAST MA. WILL NEED TO
KEEP A CLOSE EYE ON THIS TO SEE IF IT BECOMES MORE WIDESPREAD. IF
SO...A DENSE FOG ADVISORY MAY BE NEEDED. OTHERWISE VERY MUGGY
AIRMASS CONTINUES. LITTLE CHANGE TO TEMPERATURES OR POPS AT THIS
UPDATE.
PREVIOUS DISCUSSION...
MARGINAL INSTABILITY WITH DEEP LOW LEVEL MOISTURE HAS ALLOWED
ISOLATED TO SCATTERED SHOWERS TO CONTINUED TO AFFECT SOUTHERN NEW
ENGLAND. WE SHOULD SEE THIS ACTIVITY DIMINISH EARLY THIS EVENING
WITH THE LOSS OF DAYTIME HEATING.
THE MAIN CONCERN WILL BE THE SURFACE LOW PRESSURE SYSTEM OFF THE MID
ATLANTIC COAST WHICH WILL BE TRACKING NORTHEAST AND PASSING NEAR THE
BENCHMARK THIS EVENING. THE MAIN QUESTION IS HOW FAR NORTHWEST
THE RAIN SHIELD WILL GET. LATEST NEAR TERM GUIDANCE HAS BEEN
TRENDING FURTHER NORTHWEST. THEREFORE...EXPECT A PERIOD OF STEADY
RAIN ACROSS THE CAPE/ISLANDS AND PROBABLY FURTHER NORTHWEST INTO
INTERIOR SOUTHEAST MA/RHODE ISLAND FOR AT LEAST A TIME. IN
FACT...LATEST HRRR SHOWING THE POTENTIAL FOR A BRIEF PERIOD OF
RAIN ACROSS THE NORTHEAST MA COAST INCLUDING BOSTON. NOT SURE IF
IT WILL GET THAT FAR NORTHWEST...BUT ITS CERTAINLY POSSIBLE.
REGARDLESS...THE HEAVIEST RAINFALL WILL OCCUR ACROSS NANTUCKET...
WHERE BETWEEN 0.50 TO PERHAPS UP TO 1 INCH OF RAIN MAY OCCUR.
THE RAIN MAY PERSIST THROUGH MUCH OF THE EVENING ACROSS THE CAPE
AND ISLANDS...BUT SHOULD WIND DOWN NEAR OR JUST AFTER MIDNIGHT.
MEANWHILE...ONCE THE ISOLATED TO SCATTERED DIURNALLY DRIVEN
SCATTERED SHOWERS WIND DOWN EARLY THIS EVENING...THE REST OF THE
REGION WILL MAINLY BE DRY TONIGHT. HOWEVER...A COLD FRONT WILL BE
APPROACHING OUR WESTERN ZONES TOWARD MIDNIGHT. WHILE SHEAR IS QUITE
IMPRESSIVE...VERY LITTLE INSTABILITY WILL BE LEFT. SO WHILE WE MAY
SEE A FEW SPOT SHOWERS AFFECT OUR WESTERN ZONES...THEY WILL BE IN
THE PROCESS OF WEAKENING AND NOT EXPECTING MUCH MORE THAN THAT. LOW
TEMPS WILL ONLY BOTTOM OUT IN THE UPPER 50S AND THE LOWER 60S BY
DAYBREAK MONDAY.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
MONDAY...
A MUCH DRIER AIRMASS WILL WORK INTO THE REGION BEHIND
THE COLD FRONT ON MONDAY. WHILE PARTLY TO MOSTLY SUNNY SKIES ARE
EXPECTED EARLY...MAY SEE A SCATTERED TO BROKEN DECK OF STRATO-
CUMULUS CLOUDS WORK INTO AT LEAST THE INTERIOR BY AFTERNOON. HIGHS
SHOULD MAINLY BE IN THE 60S ACROSS THE INTERIOR...BUT STILL WILL
REACH BETWEEN 70 AND 75 ALONG HE COASTAL PLAIN. GUSTY WEST WINDS
OF 20 TO 30 MPH ARE EXPECTED AS BUFKIT SOUNDINGS SHOWING VERY GOOD
MIXING.
HIGH SURF...GIVEN LARGE SOUTH TO SOUTHEAST SWELL FROM DEPARTING
COASTAL LOW PRESSURE SYSTEM HAVE ISSUED A HIGH SURF ADVISORY FOR THE
SOUTH COAST ON MONDAY. WE ISSUE HIGH SURF PRODUCTS THROUGH THE END
OF SEPTEMBER IF CONDITIONS WARRANT.
MONDAY NIGHT...
HIGH PRESSURE WILL BE BUILDING IN FROM THE WEST. THIS WILL ALLOW
FOR DIMINISHING WINDS AND SKIES TO BECOME MOSTLY CLEAR. LOOKS LIKE
A PRETTY GOOD NIGHT OF RADIATIONAL COOLING...WITH LOWS BOTTOMING OUT
IN THE UPPER 30S TO THE MIDDLE 40S IN MOST LOCALES. THE URBAN HEAT
ISLAND OF BOSTON WILL BE THE MILD SPOT WITH THE LOW BOTTOMING OUT
NEAR 50.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
HIGHLIGHTS...
* HIGH PRESSURE AND DRY WEATHER THROUGH THE PERIOD
* NEAR RECORD WARMTH POSSIBLE NEXT SATURDAY
OVERVIEW...
VERY GOOD AGREEMENT AMONGST MODEL GUIDANCE THE ENTIRE FORECAST
PERIOD. AN UPPER LEVEL TROUGH DEPARTS THE NORTHEAST STATES ON
TUESDAY. THEN...MUCH ADO ABOUT BUILDING HIGH PRESSURE...BOTH AT
THE SURFACE AND ALOFT THE REMAINDER OF THE WEEK. THE UPPER RIDGE
IS VERY STRONG AS IT IS PARKED FROM THE GREAT LAKES TO SOUTHERN
NEW ENGLAND BY NEXT WEEKEND.
DETAILS... TUESDAY WILL FEATURE MOSTLY SUNNY SKIES EXCEPT ONLY
PARTLY SUNNY NW MA AND SW NH CLOSER TO SOME HIGHER 925 MB
HUMIDITY. OTHERWISE...EXPECT SUNNY DAYS AND CLEAR NIGHTS THROUGH
NEXT WEEKEND. HAVE GONE A FEW DEGREES LOWER THAN MODEL CONSENSUS
TEMPERATURE MINIMUMS THROUGH THU DUE TO EXCELLENT RADIATIONAL
COOLING EXPECTED ALONG WITH VERY DRY DEWPOINTS. AS THE CENTER OF
THE UPPER HIGH APPROACHES...AM EXPECTING A DRAMATIC WARMUP FRI
AND ESPECIALLY SAT. THE 12Z ECMWF RUN IS EVEN WARMER THAN THE
PREVIOUS RUN WITH 925 MB TEMPERATURES WARMING FROM +12C TUE...TO
+17C FRI... TO +19C OR +20C ON SAT... WITH WARM TEMPERATURES
LIKELY CONTINUING INTO EARLY THE FOLLOWING WEEK. HAVE GONE SEVERAL
DEGREES ABOVE MODEL CONSENSUS MAXIMUMS FOR NEXT SATURDAY...WITH
HIGHS SOARING TO 80 TO 85 ACROSS INTERIOR SOUTHERN NEW ENGLAND.
RECORDS FOR THAT DAY INCLUDE 85 AT WORCESTER AND 86 AT BOTH BOSTON
AND PROVIDENCE.
LIGHT WINDS ARE EXPECTED FOR THE PERIOD...SO ALTHOUGH IT WILL BE
DRY WE ARE NOT EXPECTING FIRE WEATHER CONCERNS. LOCAL SEA BREEZES
WILL OCCUR...ESPECIALLY FRI THROUGH NEXT SUNDAY. IT SHOULD BE
NOTED THAT THE GFS HAS A HINT OF A POTENTIAL BACKDOOR FRONT/TROUGH
OVER NORTHEAST MA ON SAT BUT THIS WAS NOT ENOUGH TO DETRACT FROM
THE VERY WARM FORECAST...AS YET.
AN UPPER LOW OVER VIRGINIA AND AN ASSOCIATED INVERTED TROUGH IS
LIKELY TO BE CAUSING PRECIPITATION IN THE MID ATLANTIC REGION
MID TO LATE IN THE WORK WEEK THAT TRIES TO WORK ITS WAY NORTHWARD.
THERE IS EXCELLENT MODEL AGREEMENT THAT THIS AREA ONLY GETS AS
FAR NORTHWARD AS OFF THE NJ COAST BY FRI...BEFORE RETREATING
SOUTHWARD AS STRONG HIGH PRESSURE BECOMES ESTABLISHED OVER THE
NORTHEAST ON THE WEEKEND.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH MONDAY NIGHT/...
TONIGHT...LOW TO MODERATE CONFIDENCE. IFR CONDITIONS WITH SOME
LOW IFR CONDITIONS ACROSS FAR SOUTHEAST MA INCLUDING THE CAPE AND
ISLANDS WITH VISIBILITIES BELOW 1/2 MILE AT TIMES IN LOCALLY DENSE
FOG. MOST OF THE REST OF THE REGION WILL BE MVFR CEILINGS...WITH
MANY AREAS BECOMING IFR CEILINGS BETWEEN 02Z AND 06Z. BEST
CONFIDENCE FOR IFR IS FROM ABOUT A JAFFREY-WORCESTER-WILLIMANTIC
LINE EASTWARD. STEADY RAIN WITH EMBEDDED SHOWERS WILL AFFECT THE
FAR SOUTHEAST NEW ENGLAND COAST THIS EVENING. THE RAIN WILL LIKELY
REACH INTO RHODE ISLAND/INTERIOR SOUTHEAST MA FOR A SHORT TIME AND
PERHAPS EVEN INTO NORTHEAST MA.
MONDAY AND MONDAY NIGHT...HIGH CONFIDENCE IN VFR CONDITIONS.
JUST A LOW RISK FOR BRIEF MVFR CIGS ACROSS THE INTERIOR ON MONDAY
AS A DECK OF STRATOCUMULUS CLOUDS MOVES INTO THE REGION.
OTHERWISE...GUSTY WEST TO NORTHWEST WINDS OF 20 TO 25 KNOTS
EXPECTED DURING THE DAY MONDAY.
KBOS TERMINAL...MODERATE CONFIDENCE TONIGHT WITH HIGH CONFIDENCE ON
MONDAY.
KBDL TERMINAL...MODERATE CONFIDENCE TONIGHT WITH HIGH CONFIDENCE ON
MONDAY.
OUTLOOK...TUESDAY THROUGH FRIDAY...
HIGH CONFIDENCE.
TUE...VFR.
WED...VFR
THU...VFR.
FRI...VFR.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
TONIGHT...MODERATE TO HIGH CONFIDENCE. LOW PRESSURE PASSING NEAR
THE BENCHMARK WILL RESULT IN ENOUGH SOUTH TO SOUTHEAST SWELL FOR
SCA SEAS TO DEVELOP ACROSS THE OUTER-WATERS AND WESTERN SOUNDS.
SOUTHEAST WINDS SHOULD BECOME SOUTHWEST TONIGHT AT 10 TO 15 KNOTS
LATER TONIGHT. AREAS OF FOG...SOME LOCALLY DENSE...WILL OCCUR
ACROSS THE WATERS...ESPECIALLY SOUTH OF BOSTON HARBOR.
MONDAY AND MONDAY NIGHT...MODERATE TO HIGH CONFIDENCE. SCA SEAS
ON THE WESTERN SOUNDS AND OUTER-WATERS WILL CONTINUE THROUGH
MONDAY NIGHT. IN ADDITION...A PERIOD OF WEST TO NORTHWEST WIND
GUSTS NEAR 25 KNOTS IS POSSIBLE FOR A TIME ON MONDAY.
THEREFORE...IT IS POSSIBLE WE MAY NEED TO EXPAND SCA FOR A TIME
DURING THE DAY MONDAY INTO SOME OF THE NEARSHORE SOUNDS AND
WATERS. CONFIDENCE NOT QUITE HIGH ENOUGH TO DO THIS RIGHT NOW...
SO WILL DEFER TO THE NEXT SHIFT.
OUTLOOK...TUESDAY THROUGH FRIDAY...
HIGH CONFIDENCE...
TUE AND WED...SEAS NEAR 5 FT MAY LINGER AT TIMES TUE AND WED OVER
THE WATERS S AND E OF NANTUCKET. OTHERWISE WINDS AND SEAS SHOULD
BE BELOW SMALL CRAFT ADVISORY CRITERIA. A NORTHEAST WIND GRADIENT
WILL INCREASE OVER THE SOUTHERN COASTAL WATERS TUE NIGHT INTO WED
AS STRONG HIGH PRESSURE PUSHES INTO NORTHERN NEW ENGLAND. BUT
GUSTS ARE EXPECTED TO ONLY REACH 20 KT.
WED NIGHT THROUGH FRI...QUIET BOATING WEATHER WITH HIGH PRESSURE
DOMINATING THE WEATHER. WINDS AND SEAS BELOW SCA THRESHOLDS.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...HIGH SURF ADVISORY FROM 8 AM TO 5 PM EDT MONDAY FOR MAZ020>024.
NH...NONE.
RI...HIGH SURF ADVISORY FROM 8 AM TO 5 PM EDT MONDAY FOR RIZ006>008.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 AM EDT TUESDAY FOR ANZ235-237.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT TUESDAY FOR ANZ250-254>256.
SMALL CRAFT ADVISORY FROM 6 AM TO 4 PM EDT MONDAY FOR ANZ251.
&&
$$
SYNOPSIS...FRANK/FIELD
NEAR TERM...FIELD/FRANK
SHORT TERM...FRANK
LONG TERM...FIELD
AVIATION...FIELD/FRANK
MARINE...FIELD/FRANK
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
914 PM EDT SUN SEP 21 2014
.SYNOPSIS...
LOW PRESSURE OFF THE MID-ATLANTIC COAST WILL MOVE NORTHEASTWARD AND
AWAY FROM THE REGION THROUGH TONIGHT. MEANWHILE, A COLD FRONT OVER
THE OHIO VALLEY THIS AFTERNOON WILL MOVE THROUGH OUR AREA TONIGHT.
A LARGE AREA OF HIGH PRESSURE BUILDS IN FROM THE MIDWEST EARLY IN
THE WEEK. THE HIGH IS EXPECTED TO PARK OVER THE NORTHEAST STATES
THROUGH THE REMAINDER OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
A CDFNT WAS APPROACHING FROM THE W AN A BROKEN AREA OF SHWRS WITH
A FEW EMBEDDED LIGHTNING STRIKES WAS EVIDENT ON RADAR. IT APPEARS
TO BE HOLDING TOGETHER AT IT MOVES EWD. THE HRRR INDICATES AT
LEAST SOME PORTION OF THE PRECIP WILL SURVIVE INTO THE ERN
PORTIONS OF OUR CWA. SO HAVE UPPED THE POPS INTO NJ, BUT NOT ALL
THE WAY TO THE CST JUST YET. STILL THINK WITH LOSS OF DAYTIME
HEATING AND NOT MUCH DYNAMICS TO WORK WITH THERE COULD BE SOME
WEAKENING WITH TIME. WINDS WILL SHIFT TO WRLY/NWRLY BEHIND THE
FRONT. DRIER AIR WILL OVERSPREAD THE AREA BY MORNING. LOWS WILL
DIP INTO THE LOW.MID 50S NORTH/WEST TO THE UPPER 50S/LOW 60S
SOUTH/EAST.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
A PLEASANT FALL-LIKE DAY IS EXPECTED ACROSS THE REGION MONDAY AS
COOL AND DRIER AIR CONTINUES TO BUILD OVER THE AREA. A GUSTY W/NW
WIND WILL BE IN PLACE EARLY AND CONTINUE THROUGH THE AFTERNOON. WINDS
GUSTS OF 20 TO 25 MPH ARE EXPECTED. HIGH TEMPERATURES MONDAY WILL BE
MOSTLY IN THE UPPER 60S/LOW 70S ACROSS THE AREA...WITH THE NRN MOST
AREAS ONLY HAVING HIGHS IN THE UPPER 50S (MOUNT POCONO) TO THE MID
60S. DEW POINTS MOSTLY IN THE LOW/MID 40S.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
EXPANSIVE AREA OF HIGH PRESSURE OVER THE MIDWEST WILL BUILD EASTWARD
INTO MID-ATLANTIC REGION STATES MONDAY NIGHT AND TUESDAY. MEANWHILE,
A SOUTHERN PIECE OF ENERGY ASSOCIATED WITH THE UPPER LOW THAT IS
CURRENTLY OVER THE GREAT LAKES REGION IS FORECAST TO LAG BEHIND THE
MAIN UPPER TROUGH AND POTENTIALLY DEVELOP INTO A CLOSED LOW OVER THE
SOUTHEAST STATES. A CAA REGIME WILL BECOME ESTABLISHED OVER OUR
REGION DURING THIS TIME UNDER NORTHWEST FLOW. MINIMAL CLOUD COVER
AND BELOW NORMAL TEMPS ARE EXPECTED. TEMPS MONDAY NIGHT MAY DIP INTO
THE UPPER 30S IN THE POCONOS BUT THE NW WINDS OVERNIGHT SHOULD
PRECLUDE ANY FROST FROM FORMING. WITH H8 TEMPS IN THE SINGLE DIGITS,
MAX TEMPS ON TUESDAY WILL STRUGGLE TO REACH 70F.
HIGH PRESSURE WILL RETREAT NORTHEASTWARD INTO NEW ENGLAND TUESDAY
NIGHT AND REMAIN ANCHORED THERE THROUGH THE END OF THE WEEK.
FORECAST UNCERTAINTY DECREASES DURING THE SECOND HALF OF THE WEEK AS
MODELS HAVE HAD A DIFFICULT TIME COMING TO AGREEMENT REGARDING WHAT
HAPPENS WITH THE ABOVE MENTIONED DISTURBANCE OVER THE SOUTHEAST
STATES. OVER THE PAST FEW DAYS, THE ECMWF AND GEM CONTINUE TO
ADVERTISE A STRONGER DISTURBANCE DRIFTING UP THE MID-ATLANTIC COAST
LATE IN THE WEEK, WHICH WOULD BRING RAIN TO SOUTHERN PORTIONS OF THE
AREA THURSDAY AND POSSIBLY INTO FRIDAY. MEANWHILE, THE OPERATIONAL
GFS AND JUST ABOUT ALL OF ITS GEFS MEMBERS (INCLUDING THE LATEST 12Z
RUN) HAS BEEN PERSISTENT IN SUPPRESSING THE DISTURBANCE FAR ENOUGH
TO THE SOUTH AND EAST TO KEEP US DRY. THIS HAS A LOW PREDICTABILITY
PATTERN WRITTEN ALL OVER IT GIVEN THE WEAK STEERING FLOW THE LOW
WILL ENCOUNTER UNDERNEATH THE UPPER RIDGE. OPTED TO CLOSELY FOLLOW
THE LATEST WPC GUIDANCE, WHICH PREFERRED AN IN-BETWEEN SCENARIO
USING THE 00Z ECMWF ENSEMBLE MEAN. FORECAST WAS RATHER CONSERVATIVE
WITH SLIGHT CHANCE POPS CONFINED TO THE DELMARVA AND SOUTHERN NJ.
REGARDLESS OF WHICH SOLUTION PANS OUT, THE SETUP OF HIGH PRESSURE TO
OUR NORTHEAST AND LOW PRESSURE TO OUR SOUTH WILL RESULT IN
PERSISTENT FLOW OFF THE ATLANTIC OCEAN, SEASONABLY COOL TEMPS AND
INCREASING CLOUD COVER.
THE COASTAL DISTURBANCE IS FORECAST TO MOVE OFFSHORE BY THE WEEKEND
WHILE HIGH PRESSURE BUILDS BACK INTO THE AREA. STRENGTHENING
SUBSIDENCE FROM THE HIGH OVERHEAD WOULD YIELD A WARMING TREND WITH
HIGHS POTENTIALLY NEAR 80F BOTH DAYS THIS WEEKEND.
&&
.AVIATION /01Z MONDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
VFR CONDS ARE GENLY EXPECTED. HOWEVER, THERE IS A BKN LINE OF
SHWRS MOVG ACRS ERN PA ATTM. THIS LINE COULD BRIEFLY DROP
CIGS/VSBYS INTO THE MVFR OR EVEN IFR RANGE. STILL SOME UNCERTAINTY
AS TO HOW FAR E THIS PRECIP WILL GET. HAVE ADDED SOME BRIEF
SHRA/MVFR AT KPHL...KPNE AND KTTN.
BEHIND THE FRONT WINDS WILL SHIFT TO WRLY/NWRLY AND SKIES WILL
BECOME MOSTLY CLR. MON...VFR WITH A GUSTY WNW WIND THRU THE DAY.
OUTLOOK...
MONDAY NIGHT THROUGH TUESDAY NIGHT...VFR UNDER MAINLY SKC AND
LIGHT NORTHWEST WINDS.
WEDNESDAY AND WEDNESDAY NIGHT...ONSHORE FLOW DEVELOPS. EXPECT
STRATOCU TO INCREASE AS MARINE LAYER DRAWS INLAND. SOME POTENTIAL
FOR MVFR CIGS ESPECIALLY CLOSER TO THE COAST.
THURSDAY AND FRIDAY...LOWER THAN NORMAL FORECAST CONFIDENCE AS
LOPRES OVER THE SOUTHEAST STATES DRIFTS NORTHWARD. SUB-VFR
CONDITIONS AND LIGHT RA COULD OCCUR (PARTICULARLY SOUTHERN
TERMINALS) IF THE LOW TRACKS FAR ENOUGH NORTH, WHICH IS STILL
UNCERTAIN ATTM.
&&
.MARINE...
WINDS ARE BEGINNING TO SWITCH AROUND TO NW BEHIND THE DEPARTING LOW
OFFSHORE. THE WINDS WILL REMAIN MOSTLY AROUND 10 KTS AND THEN SWITCH
MORE SWRLY THIS EVENING...BEFORE A COLD FRONT CROSSES THE WATERS
OVERNIGHT. WINDS BEHIND THE FRONT WILL SHIFT WRLY...THEN NWRLY AND
INCREASE TO 10 TO 20 KTS WITH SOME GUSTS AROUND 25 KTS. SEAS ON THE
OCEAN WILL BUILD TO AROUND 5 FT OVERNIGHT. WE HAVE ISSUED A SCA FLAG
FOR THE OCEAN WATERS AND LOWER DEL BAY TO COVER THE EXPECTED
CONDITIONS. WINDS/SEAS WILL BEGIN TO SUBSIDE BY AROUND NOON
MONDAY...SO WE WILL SET THE EXPIRATION TIME TO THAT FOR NOW...ITS
POSSIBLE IT MAY NEED TO BE EXTENDED A FEW HOURS HOWEVER.
OUTLOOK...
MONDAY NIGHT...BREEZY NW FLOW CONTINUES AS HIPRES BUILDS INTO THE
WATERS. CAPPED WINDS AROUND 20 KT, BUT STILL SOME POTENTIAL FOR A
SCA IF THE PRESSURE GRADIENT WINDS UP BEING A TAD STRONGER THAN
INDICATED BY THE LATEST GUIDANCE.
TUESDAY AND TUESDAY NIGHT...NW WINDS DIMINISH TUESDAY BEFORE
SHIFTING OUT OF THE NE TUESDAY NIGHT.
WEDNESDAY AND WEDNESDAY NIGHT...NE WINDS STRENGTHEN TO NEAR SCA
CRITERIA ON WEDNESDAY. IN RESPONSE TO THE FLOW, SEAS ARE FORECAST TO
BUILD TO AROUND 5 FT BY WEDNESDAY NIGHT.
THURSDAY THROUGH FRIDAY...FOUR TO SIX FT SEAS MAY CONTINUE THRU
THURSDAY NIGHT OR FRIDAY DESPITE A WEAKER ONSHORE FLOW. SCA MAY BE
NEEDED.
&&
.RIP CURRENTS...
A MODERATE RISK OF RIP CURRENTS IS BEING FORECAST FOR MONDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO NOON EDT MONDAY
FOR ANZ431-450>455.
&&
$$
SYNOPSIS...KLEIN
NEAR TERM...NIERENBERG/O`HARA
SHORT TERM...O`HARA
LONG TERM...KLEIN
AVIATION...KLEIN/NIERENBERG/O`HARA
MARINE...KLEIN/O`HARA
AREA FORECAST DISCUSSION...UPDATED
NWS MIAMI FL
845 PM EDT SUN SEP 21 2014
.UPDATE...
THE SHOWERS AND THUNDERSTORMS THAT BEEN OCCURRING OVER MOST OF
SOUTH FLORIDA THIS AFTERNOON HAVE MOSTLY DISSIPATED THIS
EVENING...EXCEPT OVER NORTHERN METRO MIAMI-DADE AND BROWARD
COUNTIES. THIS ACTIVITY SHOULD CONTINUE TO DISSIPATE DURING NEXT
COUPLE OF HOURS HAS THE HEATING OF THE DAY IS LOST.
THEREFORE...WILL KEEP A SLIGHT CHANCE OF POPS OVER METRO BROWARD
AND MIAMI-DADE COUNTIES THIS EVENING WHILE REST OF SOUTH FLORIDA
REMAINS DRY. THE WEATHER SHOULD THEN BE DRY FOR THE LATE NIGHT
HOURS TONIGHT OVER SOUTH FLORIDA.
A STATIONARY FRONT WILL ALSO REMAIN OVER CENTRAL FLORIDA TONIGHT
ALLOWING FOR A LIGHT SOUTHWEST WIND FLOW OVER SOUTH FLORIDA.
THIS LIGHT SOUTHWEST WIND FLOW WILL KEEP THE TROPICAL MOISTURE IN
PLACE OVER SOUTH FLORIDA TONIGHT WHICH COULD LEAD TO SOME PATCHY
FOG OVER THE INTERIOR AREAS LATE. THEREFORE...PATCHY FOG HAS BEEN
ADDED TO THE FORECAST FOR THE INTERIOR AREAS FOR THE LATE NIGHT
HOURS TONIGHT.
REST OF THE FORECAST LOOKS GOOD AT THIS TIME AND NO OTHER CHANGES
ARE PLANNED.
&&
.AVIATION...
THE SHOWERS AND THUNDERSTORMS SHOULD COME TO AN END AROUND 1Z
TONIGHT OVER THE EAST COAST TAF SITES AS THE HEATING OF THE DAY
IS LOST. SO WILL KEEP VCTS IN UNTIL 1Z FOR THEN GO DRY FOR REST
OF TONIGHT FOR THE EAST COAST TAF SITES. THE WINDS WILL ALSO BE
LIGHT AND VARIABLE TONIGHT OVER THE EAST COAST TAF SITES.
THE WINDS WILL REMAIN LIGHT AND VARIABLE UNTIL AROUND 15 TO 16Z ON
MONDAY BEFORE BECOMING SOUTHEAST AROUND 5 TO 10 KNOTS...AS THE
EAST COAST SEA BREEZE DEVELOPS AND PUSHES INLAND. THE WEATHER WILL
ALSO REMAIN DRY UNTIL 15/16Z THEN VCTS HAS BEEN ADDED TO THE EAST
COAST TAF SITES.
FOR KAPF TAF SITE...THE WINDS WILL REMAIN LIGHT AND VARIABLE
TONIGHT ALONG WITH DRY CONDITIONS. THE WINDS WILL THEN BECOME
WESTERLY AFTER 17Z ON MONDAY...AS THE WEST COAST SEA BREEZE
DEVELOPS AND PUSHES INLAND. THERE WILL ALSO BE A CHANCE OF
THUNDERSTORMS AT KAPF TAF SITE AFTER 17Z AND A VCTS HAS BEEN ADDED
TO KAPF TAF SITE AFTER 17Z ON MONDAY.
&&
.UPDATE...54/BNB
.AVIATION...54/BNB
.PREV DISCUSSION... /ISSUED 343 PM EDT SUN SEP 21 2014/
DISCUSSION...
CIRRUS CLOUDS AND SPRINKLES MOVED BACK INTO THE SOUTHERN PORTION
OF THE REGION THIS AFTERNOON...AND THIS HAS LIMITED DEVELOPMENT
THERE. IN ADDITION...WITH THE LOW LEVEL DRYING...DEW POINTS FELL
INTO THE UPPER 60S TO LOW 70S. FURTHER NORTHER...SCATTERED
SHOWERS AND STORMS WERE DEVELOPING ACROSS THE LAKE REGION SOUTH OF
THE BOUNDARY AND MOVING TOWARDS THE PALM BEACH METRO AREA. A WEAK
EAST COAST SEA BREEZE HAS ALSO DEVELOPED...AND THIS MAY ENHANCE
ACTIVITY FOR THE EAST COAST METRO AREAS MAINLY FROM BROWARD COUNTY
NORTHWARD INTO THIS EVENING.
SHOWERS/STORMS WILL DISSIPATE BEFORE MIDNIGHT ALONG THE EAST
COAST...WITH MAINLY QUIET CONDITIONS OVERNIGHT. AN UPPER TROUGH
OVER THE GREAT LAKES THIS AFTERNOON WILL DIG DOWN INTO THE
SOUTHEAST ON MONDAY AND THEN BEGIN TO LIFT OUT MONDAY NIGHT INTO
TUESDAY. CONDITIONS ON MONDAY WILL BE VERY SIMILAR TO TODAY WITH
DEEP SOUTHWESTERLY FLOW ALOFT AND DEEP MOISTURE. HIGH CLOUDS ARE
EXPECTED ONCE AGAIN ACROSS THE REGION...AND THIS COULD LIMIT
INSTABILITY.
HIGH PRESSURE WILL BUILD ACROSS THE EASTERN HALF OF THE
NATION...WITH EASTERLY FLOW RETURNING TO SOUTH FLORIDA ON TUESDAY.
A WEAK TROPICAL WAVE WILL PASS THROUGH THE CARIBBEAN...AND THE
PRESSURE GRADIENT WILL STRENGTHEN TUESDAY NIGHT ACROSS THE
ATLANTIC WATERS. SOUTHERLY FLOW ALOFT WILL TAP THIS DEEP MOISTURE
ACROSS THE CARIBBEAN...AND A WET PATTERN WILL CONTINUE. COASTAL
CONVERGENCE COMBINED WITH THE DEEP MOISTURE WILL LEAD TO NUMEROUS
SHOWERS AND SOME STORMS FOR THE EAST COAST METRO AREAS IN THE LATE
OVERNIGHT HOURS THROUGH THE LATE MORNING TUESDAY AND
WEDNESDAY...AND THEN SPREAD TO THE GULF COAST BY EARLY AFTERNOON.
SHOWER AND THUNDERSTORM CHANCES DECREASE SLIGHTLY FOR THE LATTER
HALF OF THE WEEK AS UPPER RIDGING BEGINS TO TAKE HOLD ACROSS THE
WESTERN ATLANTIC. THIS WILL ALSO BRING A RETURN TO A MORE GULF
BREEZE ORIENTED SETUP WITH AFTERNOON CONVECTION ACROSS THE
INTERIOR AND GULF COASTAL AREAS. BOTH THE GFS AND THE ECMWF THEN
AGREE WITH SLIDING THIS RIDGE FURTHER WEST AND OVER THE FLORIDA
PENINSULA FRIDAY AND INTO NEXT WEEKEND.
AVIATION...
ALTHOUGH VFR CONDITIONS SHOULD PREVAIL WITH LIGHT WINDS THROUGH
THE BULK OF 24 HR TAF PERIOD...THE LATEST HRRR MODEL RUN REMAINS
CONSISTENT AND CONTINUES TO INDICATE SCATTERED SHRAS/TSTMS
DEVELOPING AND TRACKING EASTWARD OVER THE EAST COAST TAF SITES
THROUGH THE AFTERNOON HOURS. WILL INCLUDE VCTS EXTENDING NORTH
FROM FLL AND VCSH SOUTHWARD ACROSS OPF/TMB/MIA DUE TO THE
EXTENSIVE MID/UPPER CLOUD COVERAGE THAT SHOULD CONTINUE TO LIMIT
INSTABILITY THROUGH THE PEAK HEATING HOURS TODAY OVER THESE
SOUTHERN SITES. 85/
MARINE...
AN EASTERLY FLOW REGIME WILL THEN SET UP AND PREVAIL THROUGH THE
UPCOMING WEEK AS HIGH PRESSURE RETURNS ACROSS THE WESTERN
ATLANTIC. SEAS SHOULD REMAIN AT 3 FEET OR LESS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 73 89 75 85 / 30 60 50 70
FORT LAUDERDALE 74 88 77 86 / 30 60 50 70
MIAMI 74 89 77 86 / 30 50 50 70
NAPLES 74 86 75 87 / 20 50 30 70
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...54/BNB
LONG TERM....84/AK
AVIATION...54/BNB
AREA FORECAST DISCUSSION...UPDATED
NWS MIAMI FL
443 PM EDT SAT SEP 20 2014
.UPDATE...
MOST OF THE SHOWERS AND THUNDERSTORMS THAT BEEN OCCURRING OVER THE
EASTERN AREAS OF SOUTH FLORIDA HAVE PUSHED INTO THE ATLANTIC
WATERS LATE THIS AFTERNOON. THE ONLY AREA THAT COULD STILL SEE
SOME SHOWERS AND THUNDERSTORMS IS OVER MIAMI-DADE COUNTY AS THIS
AREA HAS NOT BEEN WORK OVER YET TODAY. THEREFORE...THE POPS HAVE
BEEN LOWERED OVER MOST OF SOUTH FLORIDA...EXCEPT FOR THE SOUTHEAST
AREAS OF SOUTH FLORIDA WHERE SCATTERED POPS WILL REMAIN IN PLACE
FOR THIS AFTERNOON. FOR THE ATLANTIC WATERS...THE POPS HAVE ALSO
BEEN RAISED TO NUMEROUS COVERAGE FOR THE ON GOING SHOWER AND
THUNDERSTORM ACTIVITY.
REST OF THE FORECAST LOOKS GOOD AT THIS TIME AND NO OTHER CHANGES
ARE PLANNED.
&&
.UPDATED...54/BNB
.PREV DISCUSSION... /ISSUED 326 PM EDT SAT SEP 20 2014/
DISCUSSION...
THE SUN CAME OUT THIS AFTERNOON ACROSS THE SOUTHEASTERN PORTION OF
THE REGION...AND TEMPERATURES WERE ABLE TO GET BRIEFLY INTO THE
UPPER 80S TO AROUND 90 DEGREES. SHOWERS AND STORMS WERE BEGINNING
TO FILL IN ACROSS THE EAST COAST METRO AREAS...AND NUMEROUS TO
WIDESPREAD SHOWERS AND ISOLATED/SCATTERED STORMS WILL CONTINUE
ACROSS SOUTH FLORIDA THROUGH THE AFTERNOON HOURS. THE MAIN THREAT
THIS AFTERNOON WILL BE LOCALLY HEAVY RAINFALL AND ISOLATED STREET
FLOODING FOR THE EAST COAST METROS. GUSTY WINDS UP TO 50 MPH ARE
ALSO POSSIBLE.
TONIGHT...SHOWERS AND STORMS WILL DIMINISH SLOWLY THIS EVENING
WITH LOSS OF DAYTIME HEATING...BUT REDEVELOPMENT IS POSSIBLE
OVERNIGHT FOR THE GULF WATERS THROUGH THE NAPLES REGION. THE AREA
OF LOW PRESSURE OFF THE EAST COAST OF NORTH FLORIDA WILL MOVE
NORTHEAST OVERNIGHT...BUT THE FRONTAL BOUNDARY ACROSS CENTRAL
FLORIDA WILL REMAIN STATIONARY.
SUNDAY AND MONDAY...DEEP MOISTURE WILL REMAIN ACROSS SOUTH
FLORIDA TO THE SOUTH OF THE BOUNDARY ACROSS CENTRAL FLORIDA...WITH
PWATS AROUND 2 INCHES. WEAK UPPER TROUGHING WILL ALSO CONTINUE
ACROSS THE REGION. A FEW MID LEVEL IMPULSES SLIGHTLY DETACHED
FROM THE PARENT 500MB SHORTWAVE WELL TO THE NORTH ARE EXPECTED TO
SLIDE TO THE NORTHEAST ACROSS THE NORTHERN INTERIOR. THIS SHOULD
ENHANCE THUNDERSTORM DEVELOPMENT OVER THE AREA FOR THROUGH THE
BEGINNING OF NEXT WEEK. NUMEROUS SHOWERS AND STORMS ARE EXPECTED
EACH AFTERNOON.
A MORE EASTERLY FLOW PATTERN RETURNS TUESDAY AND SHOULD PERSIST
THROUGH THE REMAINDER OF THE WEEK AS MID LEVEL RIDGING BECOMES
FIRMLY ENTRENCHED ACROSS THE WESTERN ATLANTIC. CHANCES FOR SHOWERS
AND THUNDERSTORMS WILL PREVAIL EACH DAY WITH MODELS DEPICTING THE
DEEP MOISTURE AXIS REMAINING ACROSS SOUTH FLORIDA. MODEL SOUNDINGS
DEPICT PWAT VALUES RANGING BETWEEN 1.75-2.00 INCHES THROUGH THE
REMAINDER OF THE WEEK. THE DEEP MOISTURE AND RESULTANT CLOUD COVER
ALONG WITH AN OVERALL LACK OF DYNAMICS SHOULD KEEP THE STRONG TO
SEVERE THUNDERSTORM POTENTIAL LIMITED.
AVIATION...
SCATTERED SHOWERS AND STORMS ASSOCIATED WITH A FRONTAL BOUNDARY
AND UPPER TROUGH WILL CONTINUE TO DEVELOP AND INCREASE IN
COVERAGE ACROSS THE AREA THROUGH THE AFTERNOON HOURS. WSW FLOW
WILL FOCUS THE HEAVIEST ACTIVITY TOWARD THE EAST COAST SITES
THROUGH THIS TIME TODAY. THE FLOW SHOULD PROVE TO BE TOO STRONG
FOR THE EAST COAST SEA BREEZE TO SET UP...WHICH IS REFLECTED WELL IN
THE LATEST HRRR RUN THAT INDICATES THE ACTIVITY PUSHING THROUGH
AND OFF THE COAST THROUGH THE EARLY EVENING PERIOD. VFR CONDITIONS
SHOULD RETURN THROUGH THE LATE EVENING AND OVERNIGHT HOURS WITH
LIGHT WESTERLY FLOW CONTINUING. 85/AG
MARINE...
GENERAL SOUTHWESTERLY WINDS AT AROUND 10 KNOTS OR LESS SHOULD
PREVAIL THROUGH THE WEEKEND AS AN AREA OF LOW PRESSURE DEPARTS TO
THE NORTHEAST. A MORE EASTERLY FLOW REGIME WILL THEN SET UP
THROUGH THE FIRST PART OF NEXT WEEK AS HIGH PRESSURE RETURNS
ACROSS THE WESTERN ATLANTIC. SEAS SHOULD REMAIN AT AROUND 3 FEET
OR LESS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 73 88 75 86 / 40 50 20 60
FORT LAUDERDALE 75 88 78 87 / 40 60 20 60
MIAMI 74 88 77 87 / 40 60 20 60
NAPLES 75 87 75 86 / 50 50 20 60
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...54/BNB
LONG TERM....85/AG
AREA FORECAST DISCUSSION
NWS MIAMI FL
326 PM EDT SAT SEP 20 2014
.DISCUSSION...
THE SUN CAME OUT THIS AFTERNOON ACROSS THE SOUTHEASTERN PORTION OF
THE REGION...AND TEMPERATURES WERE ABLE TO GET BRIEFLY INTO THE
UPPER 80S TO AROUND 90 DEGREES. SHOWERS AND STORMS WERE BEGINNING
TO FILL IN ACROSS THE EAST COAST METRO AREAS...AND NUMEROUS TO
WIDESPREAD SHOWERS AND ISOLATED/SCATTERED STORMS WILL CONTINUE
ACROSS SOUTH FLORIDA THROUGH THE AFTERNOON HOURS. THE MAIN THREAT
THIS AFTERNOON WILL BE LOCALLY HEAVY RAINFALL AND ISOLATED STREET
FLOODING FOR THE EAST COAST METROS. GUSTY WINDS UP TO 50 MPH ARE
ALSO POSSIBLE.
TONIGHT...SHOWERS AND STORMS WILL DIMINISH SLOWLY THIS EVENING
WITH LOSS OF DAYTIME HEATING...BUT REDEVELOPMENT IS POSSIBLE
OVERNIGHT FOR THE GULF WATERS THROUGH THE NAPLES REGION. THE AREA
OF LOW PRESSURE OFF THE EAST COAST OF NORTH FLORIDA WILL MOVE
NORTHEAST OVERNIGHT...BUT THE FRONTAL BOUNDARY ACROSS CENTRAL
FLORIDA WILL REMAIN STATIONARY.
SUNDAY AND MONDAY...DEEP MOISTURE WILL REMAIN ACROSS SOUTH
FLORIDA TO THE SOUTH OF THE BOUNDARY ACROSS CENTRAL FLORIDA...WITH
PWATS AROUND 2 INCHES. WEAK UPPER TROUGHING WILL ALSO CONTINUE
ACROSS THE REGION. A FEW MID LEVEL IMPULSES SLIGHTLY DETACHED
FROM THE PARENT 500MB SHORTWAVE WELL TO THE NORTH ARE EXPECTED TO
SLIDE TO THE NORTHEAST ACROSS THE NORTHERN INTERIOR. THIS SHOULD
ENHANCE THUNDERSTORM DEVELOPMENT OVER THE AREA FOR THROUGH THE
BEGINNING OF NEXT WEEK. NUMEROUS SHOWERS AND STORMS ARE EXPECTED
EACH AFTERNOON.
A MORE EASTERLY FLOW PATTERN RETURNS TUESDAY AND SHOULD PERSIST
THROUGH THE REMAINDER OF THE WEEK AS MID LEVEL RIDGING BECOMES
FIRMLY ENTRENCHED ACROSS THE WESTERN ATLANTIC. CHANCES FOR SHOWERS
AND THUNDERSTORMS WILL PREVAIL EACH DAY WITH MODELS DEPICTING THE
DEEP MOISTURE AXIS REMAINING ACROSS SOUTH FLORIDA. MODEL SOUNDINGS
DEPICT PWAT VALUES RANGING BETWEEN 1.75-2.00 INCHES THROUGH THE
REMAINDER OF THE WEEK. THE DEEP MOISTURE AND RESULTANT CLOUD COVER
ALONG WITH AN OVERALL LACK OF DYNAMICS SHOULD KEEP THE STRONG TO
SEVERE THUNDERSTORM POTENTIAL LIMITED.
&&
.AVIATION...
SCATTERED SHOWERS AND STORMS ASSOCIATED WITH A FRONTAL BOUNDARY
AND UPPER TROUGH WILL CONTINUE TO DEVELOP AND INCREASE IN
COVERAGE ACROSS THE AREA THROUGH THE AFTERNOON HOURS. WSW FLOW
WILL FOCUS THE HEAVIEST ACTIVITY TOWARD THE EAST COAST SITES
THROUGH THIS TIME TODAY. THE FLOW SHOULD PROVE TO BE TOO STRONG
FOR THE EAST COAST SEA BREEZE TO SET UP...WHICH IS REFLECTED WELL IN
THE LATEST HRRR RUN THAT INDICATES THE ACTIVITY PUSHING THROUGH
AND OFF THE COAST THROUGH THE EARLY EVENING PERIOD. VFR CONDITIONS
SHOULD RETURN THROUGH THE LATE EVENING AND OVERNIGHT HOURS WITH
LIGHT WESTERLY FLOW CONTINUING. 85/AG
&&
.MARINE...
GENERAL SOUTHWESTERLY WINDS AT AROUND 10 KNOTS OR LESS SHOULD
PREVAIL THROUGH THE WEEKEND AS AN AREA OF LOW PRESSURE DEPARTS TO
THE NORTHEAST. A MORE EASTERLY FLOW REGIME WILL THEN SET UP
THROUGH THE FIRST PART OF NEXT WEEK AS HIGH PRESSURE RETURNS
ACROSS THE WESTERN ATLANTIC. SEAS SHOULD REMAIN AT AROUND 3 FEET
OR LESS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 73 88 75 86 / 40 50 20 60
FORT LAUDERDALE 75 88 78 87 / 40 60 20 60
MIAMI 74 88 77 87 / 40 60 20 60
NAPLES 75 87 75 86 / 50 50 20 60
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...84/AK
LONG TERM....84/AK
AVIATION...85/AG
AREA FORECAST DISCUSSION
NWS MIAMI FL
211 PM EDT SAT SEP 20 2014
.AVIATION...
SCATTERED SHOWERS AND STORMS ASSOCIATED WITH A FRONTAL BOUNDARY
AND UPPER TROUGH WILL CONTINUE TO DEVELOP AND INCREASE IN
COVERAGE ACROSS THE AREA THROUGH THE AFTERNOON HOURS. WSW FLOW
WILL FOCUS THE HEAVIEST ACTIVITY TOWARD THE EAST COAST SITES
THROUGH THIS TIME TODAY. THE FLOW SHOULD PROVE TO BE TOO STRONG
FOR THE EAST COAST SEA BREEZE TO SET UP...WHICH IS REFLECTED WELL IN
THE LATEST HRRR RUN THAT INDICATES THE ACTIVITY PUSHING THROUGH
AND OFF THE COAST THROUGH THE EARLY EVENING PERIOD. VFR CONDITIONS
SHOULD RETURN THROUGH THE LATE EVENING AND OVERNIGHT HOURS WITH
LIGHT WESTERLY FLOW CONTINUING. 85/AG
&&
.PREV DISCUSSION... /ISSUED 1015 AM EDT SAT SEP 20 2014/
UPDATE...
WET CONDITIONS EXPECTED AGAIN TODAY ACROSS SOUTH FLORIDA. LIGHT
SHOWERS WERE MOVING ACROSS THE GULF AND THE LAKE REGION THIS
MORNING. PWATS ON THE 12Z SOUNDING WERE JUST ABOVE 2 INCHES. AN
AREA OF LOW PRESSURE OFF THE EAST COAST OF CENTRAL FLORIDA WILL
DEEPEN AS IT MOVES NORTHEAST TODAY...WITH DEEP TRAILING MOISTURE
REMAINING ACROSS SOUTH FLORIDA. LIFT IS EXPECTED TO INCREASE
ACROSS THE LAKE REGION THROUGH THE DAY AS A SHORTWAVE ROTATES
AROUND THE BASE OF THE UPPER LOW LOCATED ACROSS THE
GEORGIA/FLORIDA BORDER. THE MAJOR LIMITING FACTOR THIS AFTERNOON
WILL BE CLOUD COVER...ESPECIALLY ACROSS THE LAKE REGION.
HOWEVER...WITH THE SYNOPTIC FEATURE ENHANCING LIFT...EXPECT
WIDESPREAD SHOWERS AND A FEW STORMS ACROSS THE NAPLES AREA AND
LAKE REGION. THE FIRST VISIBLE IMAGES THIS MORNING SHOW BREAKS
IN THE CLOUDS ACROSS THE SOUTHERN PORTION OF THE REGION...AND THE
DIFFERENTIAL HEATING MAY ALLOW FOR SHOWER AND STORM DEVELOPMENT
ACROSS THE EAST AND SOUTHEAST COAST IN THE AFTERNOON. THE HRRR AND
LOCAL WRF MODELS ARE HINTING AT THIS POSSIBILITY. SO KEPT THE
LIKELY POPS IN FOR THE REST OF THE REGION AS WELL. TEMPERATURES
WILL BE BELOW NORMAL ACROSS THE REGION DUE TO THE CLOUD COVER AND
RAINFALL.
PREV DISCUSSION... /ISSUED 855 AM EDT SAT SEP 20 2014/
AVIATION...
DESPITE THE EXTENSIVE MORNING CLOUD COVERAGE...THE LATEST VISIBLE
SATELLITE IMAGERY HAS ALREADY BEGUN TO INDICATE SOME OF THIS
COVERAGE THINNING OR BREAKING UP. IF THIS TREND
CONTINUES...DAYTIME HEATING COMBINED WITH AN UPPER TROUGH AND WEAK
FRONTAL BOUNDARY WILL SUPPORT SHRAS/TSTMS ONCE AGAIN THIS
AFTERNOON...POSSIBLY LATER DUE TO THE CURRENT CLOUD COVERAGE. WITH
THE WSW LOW-LEVEL FLOW IN PLACE...ANY SHRA/TSTM DEVELOP SHOULD
FOCUS TOWARD THE EAST COAST TODAY. 85/
PREV DISCUSSION... /ISSUED 418 AM EDT SAT SEP 20 2014/
DISCUSSION...
A WET PATTERN TO CONTINUE THROUGH THE WEEKEND AND MUCH OF NEXT
WEEK ACROSS SOUTH FLORIDA.
SHOWERS ASSOCIATED WITH A WEAK SURFACE TROUGH CONTINUE TO DIMINISH
WHILE PULLING TO THE NORTHEAST AND AWAY FROM SOUTH FLORIDA THIS
MORNING. HOWEVER...MOSTLY CLOUDY SKIES SHOULD REMAIN ACROSS THE
AREA THROUGH MUCH OF THE DAY AS A RESULT. CUTOFF H5 LOW AND
ASSOCIATED SURFACE LOW PRESSURE ACROSS NORTHERN FLORIDA ARE
EXPECTED TO SLOWLY PUSH TO THE NORTHEAST THROUGH THE DAY.
CONCURRENTLY...DEEP MOISTURE WILL CONTINUE TO SURGE INTO THE AREA
WITH MID LEVEL SOUTHWEST FLOW. THIS WILL PRODUCE PWAT VALUES OF
AROUND 2 INCHES ACROSS THE AREA RESULTING IN ANOTHER DAY OF
SHOWERS AND A FEW THUNDERSTORMS.
THE BEST COVERAGE OF SHOWERS AND STORMS LOOKS TO BE ACROSS THE
LAKE OKEECHOBEE AND PALM BEACH COUNTY AREAS WITH CLOSER PROXIMITY
TO THE H5 SHORTWAVE THUS ENHANCING LIFT. CLOUD COVER THROUGH THE
MORNING SHOULD GREATLY LIMIT STRONG THUNDERSTORM POTENTIAL THROUGH
THE AFTERNOON. VIRTUALLY ALL CONVECTIVE PARAMETERS DECREASE
THROUGH THE DAY AS A RESULT. COVERAGE OF SHOWERS AND STORMS SHOULD
DECREASE AGAIN AFTER DARK WITH LIMITED ACTIVITY LINGERING MAINLY
ACROSS THE AREA WATERS.
DEEP SOUTHWEST FLOW ALOFT SHOULD CONTINUE SUNDAY INTO MONDAY
KEEPING A DEEP MOISTURE AXIS ACROSS CENTRAL AND SOUTHERN FLORIDA.
THIS WILL KEEP A RATHER WET PATTERN THROUGH THE END OF THE WEEKEND
AND INTO THE START OF NEXT WEEK ACROSS THE AREA. A FEW MID LEVEL
IMPULSES SLIGHTLY DETACHED FROM THE PARENT H5 SHORTWAVE WELL TO
THE NORTH ARE EXPECTED TO SLIDE TO THE NORTHEAST ACROSS THE
NORTHERN INTERIOR. THIS SHOULD ENHANCE THUNDERSTORM DEVELOPMENT
SLIGHTLY OVER THE AREA FOR THE BEGINNING OF NEXT WEEK.
A MORE EASTERLY FLOW PATTERN RETURNS TUESDAY AND SHOULD PERSIST
THROUGH THE REMAINDER OF THE WEEK AS MID LEVEL RIDGING BECOMES
FIRMLY ENTRENCHED ACROSS THE WESTERN ATLANTIC. CHANCES FOR SHOWERS
AND THUNDERSTORMS WILL PREVAIL EACH DAY WITH MODELS DEPICTING THE
DEEP MOISTURE AXIS REMAINING ACROSS SOUTH FLORIDA. MODEL SOUNDINGS
DEPICT PWAT VALUES RANGING BETWEEN 1.75-2.00 INCHES THROUGH THE
REMAINDER OF THE WEEK. THE DEEP MOISTURE AND RESULTANT CLOUD COVER
ALONG WITH AN OVERALL LACK OF DYNAMICS SHOULD KEEP THE STRONG TO
SEVERE THUNDERSTORM POTENTIAL LIMITED.
AVIATION...
A WEAK TROUGH OF LOW PRESSURE OVER FLORIDA WILL DEVELOP INTO A
LOW PRESSURE SYSTEM LATER TODAY. THIS LOW WILL KEEP SHOWERS AND
SOME THUNDERSTORMS OVER SOUTH FLORIDA THROUGH THE DAY. BY THIS
EVENING, THE LOW WILL BE EXITING THE AREA AND TAKE MUCH OF THE
PRECIPITATION ALONG WITH IT. FOR TODAY, EXPECTING MOSTLY RAIN
SHOWERS IN THE MORNING AND INTO THE AFTERNOON. IN THE AFTERNOON,
THE CHANCES OF THUNDERSTORMS WILL INCREASE. HAVE PLACED THE PROB30
GROUPS LATER IN THE DAY TO REFLECT THIS FOR THE EASTERN TAF SITES.
OVERALL, MAINLY VFR/MVFR CONDITIONS ACROSS SOUTH FLORIDA, WITH
BRIEF IFR POSSIBLE UNDER HEAVY SHOWERS AND/OR THUNDERSTORMS.
MARINE...
GENERAL SOUTHWESTERLY WINDS AT AROUND 10 KNOTS OR LESS SHOULD
PREVAIL THROUGH THE WEEKEND AS AN AREA OF LOW PRESSURE DEPARTS TO
THE NORTHEAST. A MORE EASTERLY FLOW REGIME WILL THEN SET UP
THROUGH THE FIRST PART OF NEXT WEEK AS HIGH PRESSURE RETURNS
ACROSS THE WESTERN ATLANTIC. SEAS SHOULD REMAIN AT AROUND 3 FEET
OR LESS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 73 87 74 86 / 20 60 20 60
FORT LAUDERDALE 76 88 77 87 / 20 60 20 50
MIAMI 76 88 76 87 / 20 60 20 50
NAPLES 75 85 75 86 / 20 50 30 50
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...13/SI
LONG TERM....10/CD
AVIATION...13/SI
AREA FORECAST DISCUSSION
NWS MIAMI FL
1015 AM EDT SAT SEP 20 2014
.UPDATE...
WET CONDITIONS EXPECTED AGAIN TODAY ACROSS SOUTH FLORIDA. LIGHT
SHOWERS WERE MOVING ACROSS THE GULF AND THE LAKE REGION THIS
MORNING. PWATS ON THE 12Z SOUNDING WERE JUST ABOVE 2 INCHES. AN
AREA OF LOW PRESSURE OFF THE EAST COAST OF CENTRAL FLORIDA WILL
DEEPEN AS IT MOVES NORTHEAST TODAY...WITH DEEP TRAILING MOISTURE
REMAINING ACROSS SOUTH FLORIDA. LIFT IS EXPECTED TO INCREASE
ACROSS THE LAKE REGION THROUGH THE DAY AS A SHORTWAVE ROTATES
AROUND THE BASE OF THE UPPER LOW LOCATED ACROSS THE
GEORGIA/FLORIDA BORDER. THE MAJOR LIMITING FACTOR THIS AFTERNOON
WILL BE CLOUD COVER...ESPECIALLY ACROSS THE LAKE REGION.
HOWEVER...WITH THE SYNOPTIC FEATURE ENHANCING LIFT...EXPECT
WIDESPREAD SHOWERS AND A FEW STORMS ACROSS THE NAPLES AREA AND
LAKE REGION. THE FIRST VISIBLE IMAGES THIS MORNING SHOW BREAKS
IN THE CLOUDS ACROSS THE SOUTHERN PORTION OF THE REGION...AND THE
DIFFERENTIAL HEATING MAY ALLOW FOR SHOWER AND STORM DEVELOPMENT
ACROSS THE EAST AND SOUTHEAST COAST IN THE AFTERNOON. THE HRRR AND
LOCAL WRF MODELS ARE HINTING AT THIS POSSIBILITY. SO KEPT THE
LIKELY POPS IN FOR THE REST OF THE REGION AS WELL. TEMPERATURES
WILL BE BELOW NORMAL ACROSS THE REGION DUE TO THE CLOUD COVER AND
RAINFALL.
&&
.PREV DISCUSSION... /ISSUED 855 AM EDT SAT SEP 20 2014/
AVIATION...
DESPITE THE EXTENSIVE MORNING CLOUD COVERAGE...THE LATEST VISIBLE
SATELLITE IMAGERY HAS ALREADY BEGUN TO INDICATE SOME OF THIS
COVERAGE THINNING OR BREAKING UP. IF THIS TREND
CONTINUES...DAYTIME HEATING COMBINED WITH AN UPPER TROUGH AND WEAK
FRONTAL BOUNDARY WILL SUPPORT SHRAS/TSTMS ONCE AGAIN THIS
AFTERNOON...POSSIBLY LATER DUE TO THE CURRENT CLOUD COVERAGE. WITH
THE WSW LOW-LEVEL FLOW IN PLACE...ANY SHRA/TSTM DEVELOP SHOULD
FOCUS TOWARD THE EAST COAST TODAY. 85/
PREV DISCUSSION... /ISSUED 418 AM EDT SAT SEP 20 2014/
DISCUSSION...
A WET PATTERN TO CONTINUE THROUGH THE WEEKEND AND MUCH OF NEXT
WEEK ACROSS SOUTH FLORIDA.
SHOWERS ASSOCIATED WITH A WEAK SURFACE TROUGH CONTINUE TO DIMINISH
WHILE PULLING TO THE NORTHEAST AND AWAY FROM SOUTH FLORIDA THIS
MORNING. HOWEVER...MOSTLY CLOUDY SKIES SHOULD REMAIN ACROSS THE
AREA THROUGH MUCH OF THE DAY AS A RESULT. CUTOFF H5 LOW AND
ASSOCIATED SURFACE LOW PRESSURE ACROSS NORTHERN FLORIDA ARE
EXPECTED TO SLOWLY PUSH TO THE NORTHEAST THROUGH THE DAY.
CONCURRENTLY...DEEP MOISTURE WILL CONTINUE TO SURGE INTO THE AREA
WITH MID LEVEL SOUTHWEST FLOW. THIS WILL PRODUCE PWAT VALUES OF
AROUND 2 INCHES ACROSS THE AREA RESULTING IN ANOTHER DAY OF
SHOWERS AND A FEW THUNDERSTORMS.
THE BEST COVERAGE OF SHOWERS AND STORMS LOOKS TO BE ACROSS THE
LAKE OKEECHOBEE AND PALM BEACH COUNTY AREAS WITH CLOSER PROXIMITY
TO THE H5 SHORTWAVE THUS ENHANCING LIFT. CLOUD COVER THROUGH THE
MORNING SHOULD GREATLY LIMIT STRONG THUNDERSTORM POTENTIAL THROUGH
THE AFTERNOON. VIRTUALLY ALL CONVECTIVE PARAMETERS DECREASE
THROUGH THE DAY AS A RESULT. COVERAGE OF SHOWERS AND STORMS SHOULD
DECREASE AGAIN AFTER DARK WITH LIMITED ACTIVITY LINGERING MAINLY
ACROSS THE AREA WATERS.
DEEP SOUTHWEST FLOW ALOFT SHOULD CONTINUE SUNDAY INTO MONDAY
KEEPING A DEEP MOISTURE AXIS ACROSS CENTRAL AND SOUTHERN FLORIDA.
THIS WILL KEEP A RATHER WET PATTERN THROUGH THE END OF THE WEEKEND
AND INTO THE START OF NEXT WEEK ACROSS THE AREA. A FEW MID LEVEL
IMPULSES SLIGHTLY DETACHED FROM THE PARENT H5 SHORTWAVE WELL TO
THE NORTH ARE EXPECTED TO SLIDE TO THE NORTHEAST ACROSS THE
NORTHERN INTERIOR. THIS SHOULD ENHANCE THUNDERSTORM DEVELOPMENT
SLIGHTLY OVER THE AREA FOR THE BEGINNING OF NEXT WEEK.
A MORE EASTERLY FLOW PATTERN RETURNS TUESDAY AND SHOULD PERSIST
THROUGH THE REMAINDER OF THE WEEK AS MID LEVEL RIDGING BECOMES
FIRMLY ENTRENCHED ACROSS THE WESTERN ATLANTIC. CHANCES FOR SHOWERS
AND THUNDERSTORMS WILL PREVAIL EACH DAY WITH MODELS DEPICTING THE
DEEP MOISTURE AXIS REMAINING ACROSS SOUTH FLORIDA. MODEL SOUNDINGS
DEPICT PWAT VALUES RANGING BETWEEN 1.75-2.00 INCHES THROUGH THE
REMAINDER OF THE WEEK. THE DEEP MOISTURE AND RESULTANT CLOUD COVER
ALONG WITH AN OVERALL LACK OF DYNAMICS SHOULD KEEP THE STRONG TO
SEVERE THUNDERSTORM POTENTIAL LIMITED.
AVIATION...
A WEAK TROUGH OF LOW PRESSURE OVER FLORIDA WILL DEVELOP INTO A
LOW PRESSURE SYSTEM LATER TODAY. THIS LOW WILL KEEP SHOWERS AND
SOME THUNDERSTORMS OVER SOUTH FLORIDA THROUGH THE DAY. BY THIS
EVENING, THE LOW WILL BE EXITING THE AREA AND TAKE MUCH OF THE
PRECIPITATION ALONG WITH IT. FOR TODAY, EXPECTING MOSTLY RAIN
SHOWERS IN THE MORNING AND INTO THE AFTERNOON. IN THE AFTERNOON,
THE CHANCES OF THUNDERSTORMS WILL INCREASE. HAVE PLACED THE PROB30
GROUPS LATER IN THE DAY TO REFLECT THIS FOR THE EASTERN TAF SITES.
OVERALL, MAINLY VFR/MVFR CONDITIONS ACROSS SOUTH FLORIDA, WITH
BRIEF IFR POSSIBLE UNDER HEAVY SHOWERS AND/OR THUNDERSTORMS.
MARINE...
GENERAL SOUTHWESTERLY WINDS AT AROUND 10 KNOTS OR LESS SHOULD
PREVAIL THROUGH THE WEEKEND AS AN AREA OF LOW PRESSURE DEPARTS TO
THE NORTHEAST. A MORE EASTERLY FLOW REGIME WILL THEN SET UP
THROUGH THE FIRST PART OF NEXT WEEK AS HIGH PRESSURE RETURNS
ACROSS THE WESTERN ATLANTIC. SEAS SHOULD REMAIN AT AROUND 3 FEET
OR LESS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 86 73 87 74 / 80 20 60 20
FORT LAUDERDALE 87 76 88 77 / 70 20 60 20
MIAMI 86 76 88 76 / 60 20 60 20
NAPLES 83 75 85 75 / 80 20 50 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...84/AK
LONG TERM....84/AK
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
1008 PM EDT SUN SEP 21 2014
.UPDATE...
CONVECTION CONTINUES TO SLIDE SOUTHWARD ACROSS NORTH GEORGIA AND
THERE IS SOME UNCERTAINTY IN HOW THE PRECIP WILL PLAY OUT LATE
TONIGHT INTO MONDAY. OVERALL HAVE CHOSEN TO SHOW IT CONTINUING TO
SINK SOUTHWARD...BUT DECREASE THE COVERAGE FROM SCATTERED TO
ISOLATED OVERNIGHT. HRRR EXPANDS AREA OF PRECIP BY 14Z WHILE THE
LOCAL WRF ISNT QUITE THAT BOLD. CONSIDERING HRRR HAS BEEN OVERDONE
THIS SUMMER OVERALL...HAVE LEANED MORE TOWARDS THE LOCAL WRF. POP
GRIDS MAY STILL BE A TAD UNDERDONE THOUGH FOR LATE TONIGHT INTO
MONDAY.
MADE A SLIGHT INCREASE IN POPS ACROSS THE FAR SOUTHEAST PART OF
THE CWA FOR MONDAY AFTERNOON AS VORT MAX MAY HELP TO INCREASE
CONVECTION.
&&
.PREV DISCUSSION...
SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
/ISSUED 317 PM EDT SUN SEP 21 2014/
COLD FRONT IS PUSHING INTO THE TENNESSEE VALLEY AT AFD TIME WITH
ISOLATED SHOWERS DEVELOPING ALONG AND JUST AHEAD OF IT. CAPE VALUES
ARE ON THE LOW END...GENERALLY BELOW 1500 J/KG ACROSS NORTH
GEORGIA...AND BEST PVA IS ACTUALLY BEHIND THE FRONT AND DOES NOT
PUSH INTO GEORGIA REALLY UNTIL MONDAY SOMETIME. SO HAVE KEPT TREND
OF SLIGHT TO LOW CHANCE POPS WITH WORDING LIMITED TO ONLY SLIGHT
CHANCE THUNDER...ESPECIALLY SINCE WHAT CAPE MIGHT BE AROUND THIS
AFTERNOON QUICKLY DECREASES OVERNIGHT. DRY AIR STARTS FILTERING INTO
NORTH GEORGIA BEHIND THE FRONT BUT NEW RUNS ARE A LITTLE SLOWER WITH
THIS SO LOW TEMPS TONIGHT NOT FORECAST QUITE AS COOL AS WITH EARLIER
FORECASTS.
CONVECTION SHOULD FIRE ACROSS CENTRAL GEORGIA MONDAY AFTERNOON AND
WITH A PRETTY STRONG VORT LOBE SWINGING AROUND WITH THE SHARP TROUGH
ALOFT...EXPECT TO SEE A LITTLE MORE CONVECTIVE DEVELOPMENT THEN.
MUCAPES INCREASE TO BETWEEN 800-1500 J/KG ACROSS CENTRAL GEORGIA
TOMORROW DEPENDING ON WHICH MODEL ONE USES /NAM IS HIGHER AS USUAL/.
STILL HAVE LOW TO MID-RANGE CHANCE POPS AT BEST BUT WILL HAVE TO
REEVALUATE THIS OVERNIGHT.
DEEP-LAYER CAA BEHIND THE FRONT IS PRETTY IMPRESSIVE ESPECIALLY
EARLY TOMORROW ACROSS NORTH GEORGIA...THOUGH THE CAA MODERATES EVER
SO SLIGHTLY IN THE AFTERNOON. SHOULD SEE A MARKED DIFFERENCE IN
TEMPERATURES BEHIND THE FRONT TOMORROW /5-10 DEGREES COOLER EXCEPT
ACROSS SOUTHERN ZONES WHERE THE FRONT WILL NOT HAVE QUITE MADE IT
THROUGH YET/ AND ESPECIALLY TOMORROW NIGHT /ANOTHER 5-10 DEGREES
COOLER THAN TONIGHT AGAIN EXCEPT FOR SOUTHERN ZONES/. THE DECREASE
IN HUMIDITY WILL ALSO BE VERY NOTICEABLE. ENJOY THE BEAUTIFUL FALL
WEATHER!
TDP
LONG TERM /TUESDAY THROUGH SUNDAY/...
/ISSUED 317 PM EDT SUN SEP 21 2014/
HIGH PRESSURE AND COOLER TEMPERATURES WILL DOMINATE MUCH OF THE
EXTENDED FORECAST PERIOD.
HIGH PRESSURE SITUATED ACROSS THE CENTRAL OHIO VALLEY ON TUESDAY
WILL SLOWLY SHIFT EASTWARD THROUGH THE WEEK. PROLONGED EASTERLY FLOW
OFF OF THE ATLANTIC WILL HELP INCREASE THE CLOUD COVER BY WEDNESDAY.
IN ADDITION...THE OLD FRONTAL BOUNDARY ACROSS NORTH-CENTRAL FLORIDA
WILL BEGIN TO PUSH NORTHWARD AS A WARM FRONT BY LATE WEDNESDAY INTO
EARLY THURSDAY. ISENTROPIC LIFT WILL BEGIN TO INCREASE ACROSS THE
SOUTHEAST ZONES BY THE END OF THE WEEK AND SPREAD W THROUGH THE
WEEKEND. INSTABILITY LOOKS MINIMAL...BUT AN ISOLD THUNDERSTORM
CANNOT BE RULED OUT.
NLISTEMAA
AVIATION...
00Z UPDATE...
/ISSUED 737 PM EDT SUN SEP 21 2014/
MAIN FEATURE TO WATCH TONIGHT WILL BE PRECIPITATION. ALTHOUGH
THERE IS A LINE OF STORMS MOVING INTO NW GEORGIA TONIGHT...EXPECT
THE COVERAGE TO DIMINISH SOME BEFORE MAKING IT TO THE ATL AREA.
SOME SCATTERED SHOWERS STILL POSSIBLE THOUGH AS IT MAKES IT INTO
THE ATL AREA. AT THIS POINT...WILL MONITOR AND IF THE LINE HOLDS
TOGETHER WILL AMEND FOR SHRA FOR A SHORT PERIOD OF TIME.
//ATL CONFIDENCE...00Z UPDATE...
MEDIUM CONFIDENCE ON CIGS. HIGH CONFIDENCE ON VSBYS AND WIND.
11
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 64 81 56 79 / 30 20 0 0
ATLANTA 64 80 57 79 / 30 20 0 0
BLAIRSVILLE 56 74 48 76 / 30 5 0 0
CARTERSVILLE 60 78 52 80 / 30 5 0 0
COLUMBUS 68 84 59 83 / 20 20 0 0
GAINESVILLE 63 77 55 77 / 30 5 0 0
MACON 65 85 58 83 / 20 30 0 0
ROME 60 79 50 81 / 30 0 0 0
PEACHTREE CITY 62 80 52 80 / 20 20 0 0
VIDALIA 66 88 64 83 / 5 40 30 10
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...11
LONG TERM....SNELSON
AVIATION...11
AREA FORECAST DISCUSSION
NWS JACKSON KY
231 PM EDT SAT SEP 20 2014
.UPDATE...
ISSUED AT 231 PM EDT SAT SEP 20 2014
BASED ON SATELLITE TRENDS...IT LOOKS LIKE THE THREAT OF SHOWERS HAS
ENDED AS THE BETTER CU FIELD IS WELL OUT TO OUR WEST. THUS...PLAN TO
GO DRY FOR THE REMAINDER OF THE DAY. NO OTHER CHANGES MADE AT THIS
TIME.
UPDATE ISSUED AT 1019 AM EDT SAT SEP 20 2014
BASED ON THE EXPANSION OF THE MID LEVEL AC HAVE OPTED TO GO AHEAD AND
EXPAND THE ISOLATED SHOWERS TO MOST OF EASTERN KENTUCKY. THE MID
LEVEL AC HAS A FEW VERTICAL TOWERS ALREADY SEEN FROM THE OFFICE. WITH
SOME WEAK INSTABILITY COMBINED WITH THE MID LEVEL INSTABILITY...WE
SHOULD SEE A FEW SHOWERS POP UP THIS AFTERNOON. EVERYTHING SHOULD
REMAIN FAIRLY ISOLATED AND THUNDER DOES NOT LOOK LIKE A THREAT AS
INSTABILITY IS NOT STRONG ENOUGH TO SUPPORT IT. OTHERWISE...NO OTHER
CHANGES PLANNED AT THIS TIME.
UPDATE ISSUED AT 740 AM EDT SAT SEP 20 2014
HOURLY GRIDS HAVE BEEN FRESHENED UP BASED ON RECENT OBSERVATIONS AND
SATELLITE TRENDS. THIS LED TO SOME MINOR ADJUSTMENTS TO HOURLY
TEMPS AND DEWPOINTS TO START THE PERIOD. ANY LINGERING VALLEY FOG
SHOULD BE LIFTING AND DISSIPATING SHORTLY...IF IT HAS NOT ALREADY
DONE SO. WX GRIDS WERE UPDATED ACCORDINGLY AND AN UPDATED ZFP AND HWO
WILL FOLLOW SHORTLY.
CONFIDENCE IN THE EVOLUTION AND PLACEMENT OF ANY SHOWERS
LATER TODAY REMAINS LOWER THAN AVERAGE. THE NAM HAS BEEN THE MOST
INSISTENT ON ISOLATED SHOWER CHANCES FOR TODAY WHILE THE RECENT HRRR
RUNS POINT TOWARD THE POTENTIAL FOR A STRAY SHOWER JUST ABOUT
ANYWHERE IN THE CWA THIS MORNING INTO THE AFTERNOON...BUT ALSO HAD
ACTIVITY EARLIER IN THE MODEL RUN...BETWEEN 8Z AND PRESENT WHICH DID
NOT MATERIALIZE. THE CURRENT FORECAST HAS THE SLIGHT CHANCES ACROSS
THE WEST OR NORTHWEST IN LINE WITH THE HIGHEST 3Z SREF POPS.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 355 AM EDT SAT SEP 20 2014
EARLY THIS MORNING...AN UPPER LEVEL RIDGE OF HIGH PRESSURE CENTERED
OVER THE SOUTHERN ROCKIES TO SOUTHERN PLAINS REGION WITH RIDGING EAST
INTO THE LOWER OH VALLEY WAS IN PLACE. ACROSS THE SOUTHEASTERN US...
A BROAD UPPER LEVEL LOW WAS PRESENT. MEANWHILE A SERIES OF SHORTWAVES
WERE IN THE NORTHERN STREAM WITH A WEAK LEAD SHORTWAVE NEAR THE MID
MS VALLEY REGION WITH ANOTHER SHORTWAVE NEARING THE NORTHERN GREAT
LAKES EXTENDING FROM WESTERN ONTARIO INTO THE UPPER MIDWEST AND DOWN
INTO THE CENTRAL PLAINS REGION. FURTHER NORTHWEST ANOTHER SHORTWAVE
IS MOVING ACROSS THE CANADIAN PLAINS.
THROUGH THE SHORT TERM PERIOD...THE LEAD WEAK SHORTWAVE WILL WORK
ACROSS THE AREA THROUGH EARLY TO MID AFTERNOON AS HEIGHTS BEGIN TO
FALL IN THE OH VALLEY REGION WHILE THE UPPER LEVEL RIDGE BUILDING
NORTH ACROSS THE ROCKIES AND INTO THE INTERIOR NORTHWESTERN US.
DOWNSTREAM ACROSS THE GREAT LAKES AND EASTERN US...A TROUGH OF LOW
PRESSURE WILL BEGIN TO BE CARVED OUT BY THE TWO MAIN SHORTWAVES AND
SOUTHEASTERN CONUS TROUGH BEGINNING TO MERGE INTO IT. THE ASSOCIATED
SFC LOW WILL TRACK WELL NORTH OF KY...BUT THE TRAILING COLD FRONT
WILL WORK INTO THE LOWER OH VALLEY REGION TONIGHT AND THEN MOVE
ACROSS THE COMMONWEALTH THROUGH THE END OF THE PERIOD...WHEN IT
SHOULD BE CLOSE TO EXITING INTO VA.
SCATTERED TO BROKEN CLOUDS IN THE 4 TO 7KFT RANGE HAVE DEVELOPED
OVERNIGHT IN THE WARM SECTOR. OUTSIDE OF THESE CLOUDS VALLEY FOG IS
LIKELY STILL PRESENT AND MAY BE DENSE AT LEAST IN SOME SPOTS ALONG THE
RIVERS AND LARGER STREAMS AND LAKES. DEWPOINT DEPRESSIONS ARE LARGER
NEARER TO THE VA BORDER WHERE A DOWNSLOPE FLOW HAS BEEN PRESENT WITH
SPEEDS OF 10 MPH OR MORE ACROSS THE HIGH TERRAIN AND OBSERVATIONS
SUPPORT ANY FOG BEING MUCH MORE LOCALIZED THERE. THIS FOG SHOULD
GRADUALLY BEGIN TO LIFT THROUGH SUNRISE AND THEN DISSIPATE BY A
COUPLE OF HOURS AFTER SUNRISE. IN ADDITION...WHERE CLOUDS FORM THIS
FOG WILL TEND TO DISSIPATE AS WELL.
THE MODEL GUIDANCE BRINGS THE WEAK MID LEVEL DISTURBANCE TOWARD THE
AREA FOR THE REMAINDER OF THE NIGHT AND INTO THE EARLY AFTERNOON.
THE 0Z NAM AND SOME OF THE NEAR TERM GUIDANCE SUCH AS THE HRRR ALSO
DEVELOP SOME CONVECTION THIS MORNING THROUGH EARLY AFTERNOON MAINLY
ACROSS THE WESTERN HALF OF THE CWA. MOS GUIDANCE ACROSS THESE
LOCATIONS DOES NOT HAVE A SLIGHT CHANCE POPS AND MODEL CONSENSUS
BLENDS GENERALLY STAYED BELOW SLIGHT AS WELL. HOWEVER...WE OPTED TO
GO WITH SLIGHT CHANCE IN THESE WESTERN LOCATIONS FOR TODAY...WHICH
WAS IN BETTER AGREEMENT WITH SURROUNDING WFOS.
THE MAIN PRECIPITATION CHANCE DURING THE SHORT TERM PERIOD AND THE
ENTIRE FORECAST PERIOD FOR THAT MATTER WILL COME AS THE TROUGH
BEGINS TO TAKE SHAPE LATE TONIGHT INTO THE DAY ON SUNDAY AND THE COLD
FRONT ENTERS EASTERN KY. THIS COLD FRONT AND THE APPROACHING TROUGH
IS EXPECTED TO BRING A BAND OF SCATTERED OR BETTER COVERAGE OF
CONVECTION AS IT WILL BE MOVING ACROSS EASTERN KY DURING THE DAYTIME.
ISOLATED TO SCATTERED CONVECTION MAY REACH THE NORTHERN PART OF THE
CWA TOWARD DAWN...BUT THE BEST CHANCE FOR CONVECTION WILL BE CLOSER
TO THE COLD FRONT GENERALLY DURING THE AFTERNOON HOURS. THUNDERSTORMS
WILL BE CAPABLE OF BRIEF HEAVY RAIN AND POSSIBLY SOME GUSTY
WINDS...PENDING THE DEGREE OF INSTABILITY.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 324 AM EDT SAT SEP 20 2014
A QUICK MOVING COLD FRONT WILL BE EXITING THE REGION AS OF 0Z MONDAY.
MODELS CONTINUE TO COME INTO A BETTER AGREEMENT FOR THE ENDING TIME
OF PRECIP ASSOCIATED WITH THE FRONT...WITH THE NW EXPECTED TO CLEAR
OUT BY 0Z...AND FINALLY THE SE JUST AFTER 6Z MONDAY. LATEST FORECAST
SOUNDINGS ARE STILL ONLY SUPPORTING MARGINAL INSTABILITY FOR THE
PRECIP ACCOMPANYING THIS FRONT...QUICKLY DISSIPATING AS WE LOSE
DAYTIME HEATING...AND ONCE THE FRONTAL BOUNDARY HAS PASSED. AS
SUCH...THUNDER WAS MENTIONED IN PREVIOUS FORECAST PAST 0Z...AND HAS
ALSO BEEN INCLUDED BY SURROUNDING OFFICES THROUGH THE FIRST PART OF
THE EVENING. DID NOT FEEL CONFIDENT ENOUGH TO YANK MENTION OF THUNDER
COMPLETELY AT 0Z...SO KEPT MENTION OF SLIGHT CHANCE THUNDER WITH
CHANCE POPS THROUGH 3Z...WHICH CONSEQUENTLY IS ABOUT THE SAME TIME
CHANCE POPS EXIT THE REGION ANYWAYS. THERE IS SOME CONCERN THAT THE
COMBINATION OF STRONG SUBSIDENCE BEHIND THE FRONT...IN ADDITION TO
THE LINGERING MOISTURE ACROSS THE REGION...WILL LEAD TO A WIDESPREAD
FOG EVENT BY LATE SUNDAY NIGHT...OR PERHAPS A LOW STRATUS EVENT. THE
EXTENT OF EITHER OF THESE IS STILL SOMEWHAT UNCERTAIN. DECIDED TO
INCREASE CLOUDS SLIGHTLY OVERNIGHT SUNDAY NIGHT/MONDAY MORNING...BUT
DID NOT MENTION FOG AT THIS TIME.
AS THE FRONT QUICKLY DEPARTS SUNDAY EVENING/NIGHT...KY WILL FIND
ITSELF ON THE BACKSIDE OF THE UPPER LEVEL TROUGHING PATTERN...WITH
STRONG NW FLOW BRINGING MUCH COOLER CANADIAN AIR INTO THE REGION. AS
HIGH PRESSURE TAKES HOLD...DRY AND SUNNY SKIES WILL PREVAIL DURING
THE DAY MONDAY...BUT HIGH TEMPERATURES WILL STRUGGLE TO MAKE IT TO
THE 70 DEGREE MARK. AIRMASS MODIFICATION...NAMELY THE LESSENING OF
STRONG PRESSURE GRADIENT/NW FLOW AS THE UPPER LEVEL RIDGE TAKES FULL
CONTROL...WILL SLOWLY ALLOW TEMPS TO RISE THROUGHOUT THE REMAINDER
OF THE EXTENDED FORECAST PERIOD. HOWEVER WE LIKELY WON/T SEE TEMPS
HIT ABOVE THE 80 DEGREE MARK AGAIN UNTIL AT LEAST NEXT WEEKEND.
MEANWHILE...WITH SUCH STRONG SUBSIDENCE IN CONTROL...THERE WILL BE
LITTLE CONCERN FOR CLOUDS...LET ALONE PRECIP CHANCES. ALL IN ALL IT
LOOKS TO BE A GORGEOUS AUTUMN-LIKE WEEK AHEAD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 231 PM EDT SAT SEP 20 2014
VFR CONDITIONS WILL CONTINUE OVER THE NEXT 24 TO 36 HOURS. SOME
PATCHY VALLEY FOG WILL BE POSSIBLE AGAIN TONIGHT. A COLD FRONT WILL
DROP SOUTH INTO THE AREA TOMORROW MORNING WITH CLOUDS AND
PRECIPITATION CHANCES ON THE INCREASE. AT THIS TIME...IT APPEARS CIGS
SHOULD REMAIN AT OR ABOVE 3500 FEET.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KAS
SHORT TERM...JP
LONG TERM...JMW
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
1019 AM EDT SAT SEP 20 2014
.UPDATE...
ISSUED AT 1019 AM EDT SAT SEP 20 2014
BASED ON THE EXPANSION OF THE MID LEVEL AC HAVE OPTED TO GO AHEAD AND
EXPAND THE ISOLATED SHOWERS TO MOST OF EASTERN KENTUCKY. THE MID
LEVEL AC HAS A FEW VERTICAL TOWERS ALREADY SEEN FROM THE OFFICE. WITH
SOME WEAK INSTABILITY COMBINED WITH THE MID LEVEL INSTABILITY...WE
SHOULD SEE A FEW SHOWERS POP UP THIS AFTERNOON. EVERYTHING SHOULD
REMAIN FAIRLY ISOLATED AND THUNDER DOES NOT LOOK LIKE A THREAT AS
INSTABILITY IS NOT STRONG ENOUGH TO SUPPORT IT. OTHERWISE...NO OTHER
CHANGES PLANNED AT THIS TIME.
UPDATE ISSUED AT 740 AM EDT SAT SEP 20 2014
HOURLY GRIDS HAVE BEEN FRESHENED UP BASED ON RECENT OBSERVATIONS AND
SATELLITE TRENDS. THIS LED TO SOME MINOR ADJUSTMENTS TO HOURLY
TEMPS AND DEWPOINTS TO START THE PERIOD. ANY LINGERING VALLEY FOG
SHOULD BE LIFTING AND DISSIPATING SHORTLY...IF IT HAS NOT ALREADY
DONE SO. WX GRIDS WERE UPDATED ACCORDINGLY AND AN UPDATED ZFP AND HWO
WILL FOLLOW SHORTLY.
CONFIDENCE IN THE EVOLUTION AND PLACEMENT OF ANY SHOWERS
LATER TODAY REMAINS LOWER THAN AVERAGE. THE NAM HAS BEEN THE MOST
INSISTENT ON ISOLATED SHOWER CHANCES FOR TODAY WHILE THE RECENT HRRR
RUNS POINT TOWARD THE POTENTIAL FOR A STRAY SHOWER JUST ABOUT
ANYWHERE IN THE CWA THIS MORNING INTO THE AFTERNOON...BUT ALSO HAD
ACTIVITY EARLIER IN THE MODEL RUN...BETWEEN 8Z AND PRESENT WHICH DID
NOT MATERIALIZE. THE CURRENT FORECAST HAS THE SLIGHT CHANCES ACROSS
THE WEST OR NORTHWEST IN LINE WITH THE HIGHEST 3Z SREF POPS.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 355 AM EDT SAT SEP 20 2014
EARLY THIS MORNING...AN UPPER LEVEL RIDGE OF HIGH PRESSURE CENTERED
OVER THE SOUTHERN ROCKIES TO SOUTHERN PLAINS REGION WITH RIDGING EAST
INTO THE LOWER OH VALLEY WAS IN PLACE. ACROSS THE SOUTHEASTERN US...
A BROAD UPPER LEVEL LOW WAS PRESENT. MEANWHILE A SERIES OF SHORTWAVES
WERE IN THE NORTHERN STREAM WITH A WEAK LEAD SHORTWAVE NEAR THE MID
MS VALLEY REGION WITH ANOTHER SHORTWAVE NEARING THE NORTHERN GREAT
LAKES EXTENDING FROM WESTERN ONTARIO INTO THE UPPER MIDWEST AND DOWN
INTO THE CENTRAL PLAINS REGION. FURTHER NORTHWEST ANOTHER SHORTWAVE
IS MOVING ACROSS THE CANADIAN PLAINS.
THROUGH THE SHORT TERM PERIOD...THE LEAD WEAK SHORTWAVE WILL WORK
ACROSS THE AREA THROUGH EARLY TO MID AFTERNOON AS HEIGHTS BEGIN TO
FALL IN THE OH VALLEY REGION WHILE THE UPPER LEVEL RIDGE BUILDING
NORTH ACROSS THE ROCKIES AND INTO THE INTERIOR NORTHWESTERN US.
DOWNSTREAM ACROSS THE GREAT LAKES AND EASTERN US...A TROUGH OF LOW
PRESSURE WILL BEGIN TO BE CARVED OUT BY THE TWO MAIN SHORTWAVES AND
SOUTHEASTERN CONUS TROUGH BEGINNING TO MERGE INTO IT. THE ASSOCIATED
SFC LOW WILL TRACK WELL NORTH OF KY...BUT THE TRAILING COLD FRONT
WILL WORK INTO THE LOWER OH VALLEY REGION TONIGHT AND THEN MOVE
ACROSS THE COMMONWEALTH THROUGH THE END OF THE PERIOD...WHEN IT
SHOULD BE CLOSE TO EXITING INTO VA.
SCATTERED TO BROKEN CLOUDS IN THE 4 TO 7KFT RANGE HAVE DEVELOPED
OVERNIGHT IN THE WARM SECTOR. OUTSIDE OF THESE CLOUDS VALLEY FOG IS
LIKELY STILL PRESENT AND MAY BE DENSE AT LEAST IN SOME SPOTS ALONG THE
RIVERS AND LARGER STREAMS AND LAKES. DEWPOINT DEPRESSIONS ARE LARGER
NEARER TO THE VA BORDER WHERE A DOWNSLOPE FLOW HAS BEEN PRESENT WITH
SPEEDS OF 10 MPH OR MORE ACROSS THE HIGH TERRAIN AND OBSERVATIONS
SUPPORT ANY FOG BEING MUCH MORE LOCALIZED THERE. THIS FOG SHOULD
GRADUALLY BEGIN TO LIFT THROUGH SUNRISE AND THEN DISSIPATE BY A
COUPLE OF HOURS AFTER SUNRISE. IN ADDITION...WHERE CLOUDS FORM THIS
FOG WILL TEND TO DISSIPATE AS WELL.
THE MODEL GUIDANCE BRINGS THE WEAK MID LEVEL DISTURBANCE TOWARD THE
AREA FOR THE REMAINDER OF THE NIGHT AND INTO THE EARLY AFTERNOON.
THE 0Z NAM AND SOME OF THE NEAR TERM GUIDANCE SUCH AS THE HRRR ALSO
DEVELOP SOME CONVECTION THIS MORNING THROUGH EARLY AFTERNOON MAINLY
ACROSS THE WESTERN HALF OF THE CWA. MOS GUIDANCE ACROSS THESE
LOCATIONS DOES NOT HAVE A SLIGHT CHANCE POPS AND MODEL CONSENSUS
BLENDS GENERALLY STAYED BELOW SLIGHT AS WELL. HOWEVER...WE OPTED TO
GO WITH SLIGHT CHANCE IN THESE WESTERN LOCATIONS FOR TODAY...WHICH
WAS IN BETTER AGREEMENT WITH SURROUNDING WFOS.
THE MAIN PRECIPITATION CHANCE DURING THE SHORT TERM PERIOD AND THE
ENTIRE FORECAST PERIOD FOR THAT MATTER WILL COME AS THE TROUGH
BEGINS TO TAKE SHAPE LATE TONIGHT INTO THE DAY ON SUNDAY AND THE COLD
FRONT ENTERS EASTERN KY. THIS COLD FRONT AND THE APPROACHING TROUGH
IS EXPECTED TO BRING A BAND OF SCATTERED OR BETTER COVERAGE OF
CONVECTION AS IT WILL BE MOVING ACROSS EASTERN KY DURING THE DAYTIME.
ISOLATED TO SCATTERED CONVECTION MAY REACH THE NORTHERN PART OF THE
CWA TOWARD DAWN...BUT THE BEST CHANCE FOR CONVECTION WILL BE CLOSER
TO THE COLD FRONT GENERALLY DURING THE AFTERNOON HOURS. THUNDERSTORMS
WILL BE CAPABLE OF BRIEF HEAVY RAIN AND POSSIBLY SOME GUSTY
WINDS...PENDING THE DEGREE OF INSTABILITY.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 324 AM EDT SAT SEP 20 2014
A QUICK MOVING COLD FRONT WILL BE EXITING THE REGION AS OF 0Z MONDAY.
MODELS CONTINUE TO COME INTO A BETTER AGREEMENT FOR THE ENDING TIME
OF PRECIP ASSOCIATED WITH THE FRONT...WITH THE NW EXPECTED TO CLEAR
OUT BY 0Z...AND FINALLY THE SE JUST AFTER 6Z MONDAY. LATEST FORECAST
SOUNDINGS ARE STILL ONLY SUPPORTING MARGINAL INSTABILITY FOR THE
PRECIP ACCOMPANYING THIS FRONT...QUICKLY DISSIPATING AS WE LOSE
DAYTIME HEATING...AND ONCE THE FRONTAL BOUNDARY HAS PASSED. AS
SUCH...THUNDER WAS MENTIONED IN PREVIOUS FORECAST PAST 0Z...AND HAS
ALSO BEEN INCLUDED BY SURROUNDING OFFICES THROUGH THE FIRST PART OF
THE EVENING. DID NOT FEEL CONFIDENT ENOUGH TO YANK MENTION OF THUNDER
COMPLETELY AT 0Z...SO KEPT MENTION OF SLIGHT CHANCE THUNDER WITH
CHANCE POPS THROUGH 3Z...WHICH CONSEQUENTLY IS ABOUT THE SAME TIME
CHANCE POPS EXIT THE REGION ANYWAYS. THERE IS SOME CONCERN THAT THE
COMBINATION OF STRONG SUBSIDENCE BEHIND THE FRONT...IN ADDITION TO
THE LINGERING MOISTURE ACROSS THE REGION...WILL LEAD TO A WIDESPREAD
FOG EVENT BY LATE SUNDAY NIGHT...OR PERHAPS A LOW STRATUS EVENT. THE
EXTENT OF EITHER OF THESE IS STILL SOMEWHAT UNCERTAIN. DECIDED TO
INCREASE CLOUDS SLIGHTLY OVERNIGHT SUNDAY NIGHT/MONDAY MORNING...BUT
DID NOT MENTION FOG AT THIS TIME.
AS THE FRONT QUICKLY DEPARTS SUNDAY EVENING/NIGHT...KY WILL FIND
ITSELF ON THE BACKSIDE OF THE UPPER LEVEL TROUGHING PATTERN...WITH
STRONG NW FLOW BRINGING MUCH COOLER CANADIAN AIR INTO THE REGION. AS
HIGH PRESSURE TAKES HOLD...DRY AND SUNNY SKIES WILL PREVAIL DURING
THE DAY MONDAY...BUT HIGH TEMPERATURES WILL STRUGGLE TO MAKE IT TO
THE 70 DEGREE MARK. AIRMASS MODIFICATION...NAMELY THE LESSENING OF
STRONG PRESSURE GRADIENT/NW FLOW AS THE UPPER LEVEL RIDGE TAKES FULL
CONTROL...WILL SLOWLY ALLOW TEMPS TO RISE THROUGHOUT THE REMAINDER
OF THE EXTENDED FORECAST PERIOD. HOWEVER WE LIKELY WON/T SEE TEMPS
HIT ABOVE THE 80 DEGREE MARK AGAIN UNTIL AT LEAST NEXT WEEKEND.
MEANWHILE...WITH SUCH STRONG SUBSIDENCE IN CONTROL...THERE WILL BE
LITTLE CONCERN FOR CLOUDS...LET ALONE PRECIP CHANCES. ALL IN ALL IT
LOOKS TO BE A GORGEOUS AUTUMN-LIKE WEEK AHEAD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 748 AM EDT SAT SEP 20 2014
ASIDE FROM ANY LINGERING VALLEY FOG LIFTING AND DISSIPATING THROUGH
13Z TO 14Z...VFR CONDITIONS WITH LIGHT WINDS WILL PREVAIL DURING THE
PERIOD. A COLD FRONT AND APPROACHING UPPER LEVEL SYSTEM WILL BRING
AN INCREASE IN CLOUDS LATER IN THE PERIOD...AND ISOLATED SHOWERS OR
PERHAPS A THUNDERSTORM COULD AFFECT AREAS NORTH OF A SME TO LOZ TO
JKL TO SJS LINE VERY LATE IN THE PERIOD. A FEW VALLEY LOCATIONS MAY
AGAIN EXPERIENCE FOG BETWEEN 3Z AND 12Z WITH VIS RESTRICTIONS DOWN TO
IFR OR MVFR...BUT THIS SHOULD NOT AFFECT THE TAF SITES.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KAS
SHORT TERM...JP
LONG TERM...JMW
AVIATION...JP
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
753 AM EDT SAT SEP 20 2014
.UPDATE...
ISSUED AT 740 AM EDT SAT SEP 20 2014
HOURLY GRIDS HAVE BEEN FRESHENED UP BASED ON RECENT OBSERVATIONS AND
SATELLITE TRENDS. THIS LED TO SOME MINOR ADJUSTMENTS TO HOURLY
TEMPS AND DEWPOINTS TO START THE PERIOD. ANY LINGERING VALLEY FOG
SHOULD BE LIFTING AND DISSIPATING SHORTLY...IF IT HAS NOT ALREADY
DONE SO. WX GRIDS WERE UPDATED ACCORDINGLY AND AN UPDATED ZFP AND HWO
WILL FOLLOW SHORTLY.
CONFIDENCE IN THE EVOLUTION AND PLACEMENT OF ANY SHOWERS
LATER TODAY REMAINS LOWER THAN AVERAGE. THE NAM HAS BEEN THE MOST
INSISTENT ON ISOLATED SHOWER CHANCES FOR TODAY WHILE THE RECENT HRRR
RUNS POINT TOWARD THE POTENTIAL FOR A STRAY SHOWER JUST ABOUT
ANYWHERE IN THE CWA THIS MORNING INTO THE AFTERNOON...BUT ALSO HAD
ACTIVITY EARLIER IN THE MODEL RUN...BETWEEN 8Z AND PRESENT WHICH DID
NOT MATERIALIZE. THE CURRENT FORECAST HAS THE SLIGHT CHANCES ACROSS
THE WEST OR NORTHWEST IN LINE WITH THE HIGHEST 3Z SREF POPS.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 355 AM EDT SAT SEP 20 2014
EARLY THIS MORNING...AN UPPER LEVEL RIDGE OF HIGH PRESSURE CENTERED
OVER THE SOUTHERN ROCKIES TO SOUTHERN PLAINS REGION WITH RIDGING EAST
INTO THE LOWER OH VALLEY WAS IN PLACE. ACROSS THE SOUTHEASTERN US...
A BROAD UPPER LEVEL LOW WAS PRESENT. MEANWHILE A SERIES OF SHORTWAVES
WERE IN THE NORTHERN STREAM WITH A WEAK LEAD SHORTWAVE NEAR THE MID
MS VALLEY REGION WITH ANOTHER SHORTWAVE NEARING THE NORTHERN GREAT
LAKES EXTENDING FROM WESTERN ONTARIO INTO THE UPPER MIDWEST AND DOWN
INTO THE CENTRAL PLAINS REGION. FURTHER NORTHWEST ANOTHER SHORTWAVE
IS MOVING ACROSS THE CANADIAN PLAINS.
THROUGH THE SHORT TERM PERIOD...THE LEAD WEAK SHORTWAVE WILL WORK
ACROSS THE AREA THROUGH EARLY TO MID AFTERNOON AS HEIGHTS BEGIN TO
FALL IN THE OH VALLEY REGION WHILE THE UPPER LEVEL RIDGE BUILDING
NORTH ACROSS THE ROCKIES AND INTO THE INTERIOR NORTHWESTERN US.
DOWNSTREAM ACROSS THE GREAT LAKES AND EASTERN US...A TROUGH OF LOW
PRESSURE WILL BEGIN TO BE CARVED OUT BY THE TWO MAIN SHORTWAVES AND
SOUTHEASTERN CONUS TROUGH BEGINNING TO MERGE INTO IT. THE ASSOCIATED
SFC LOW WILL TRACK WELL NORTH OF KY...BUT THE TRAILING COLD FRONT
WILL WORK INTO THE LOWER OH VALLEY REGION TONIGHT AND THEN MOVE
ACROSS THE COMMONWEALTH THROUGH THE END OF THE PERIOD...WHEN IT
SHOULD BE CLOSE TO EXITING INTO VA.
SCATTERED TO BROKEN CLOUDS IN THE 4 TO 7KFT RANGE HAVE DEVELOPED
OVERNIGHT IN THE WARM SECTOR. OUTSIDE OF THESE CLOUDS VALLEY FOG IS
LIKELY STILL PRESENT AND MAY BE DENSE AT LEAST IN SOME SPOTS ALONG THE
RIVERS AND LARGER STREAMS AND LAKES. DEWPOINT DEPRESSIONS ARE LARGER
NEARER TO THE VA BORDER WHERE A DOWNSLOPE FLOW HAS BEEN PRESENT WITH
SPEEDS OF 10 MPH OR MORE ACROSS THE HIGH TERRAIN AND OBSERVATIONS
SUPPORT ANY FOG BEING MUCH MORE LOCALIZED THERE. THIS FOG SHOULD
GRADUALLY BEGIN TO LIFT THROUGH SUNRISE AND THEN DISSIPATE BY A
COUPLE OF HOURS AFTER SUNRISE. IN ADDITION...WHERE CLOUDS FORM THIS
FOG WILL TEND TO DISSIPATE AS WELL.
THE MODEL GUIDANCE BRINGS THE WEAK MID LEVEL DISTURBANCE TOWARD THE
AREA FOR THE REMAINDER OF THE NIGHT AND INTO THE EARLY AFTERNOON.
THE 0Z NAM AND SOME OF THE NEAR TERM GUIDANCE SUCH AS THE HRRR ALSO
DEVELOP SOME CONVECTION THIS MORNING THROUGH EARLY AFTERNOON MAINLY
ACROSS THE WESTERN HALF OF THE CWA. MOS GUIDANCE ACROSS THESE
LOCATIONS DOES NOT HAVE A SLIGHT CHANCE POPS AND MODEL CONSENSUS
BLENDS GENERALLY STAYED BELOW SLIGHT AS WELL. HOWEVER...WE OPTED TO
GO WITH SLIGHT CHANCE IN THESE WESTERN LOCATIONS FOR TODAY...WHICH
WAS IN BETTER AGREEMENT WITH SURROUNDING WFOS.
THE MAIN PRECIPITATION CHANCE DURING THE SHORT TERM PERIOD AND THE
ENTIRE FORECAST PERIOD FOR THAT MATTER WILL COME AS THE TROUGH
BEGINS TO TAKE SHAPE LATE TONIGHT INTO THE DAY ON SUNDAY AND THE COLD
FRONT ENTERS EASTERN KY. THIS COLD FRONT AND THE APPROACHING TROUGH
IS EXPECTED TO BRING A BAND OF SCATTERED OR BETTER COVERAGE OF
CONVECTION AS IT WILL BE MOVING ACROSS EASTERN KY DURING THE DAYTIME.
ISOLATED TO SCATTERED CONVECTION MAY REACH THE NORTHERN PART OF THE
CWA TOWARD DAWN...BUT THE BEST CHANCE FOR CONVECTION WILL BE CLOSER
TO THE COLD FRONT GENERALLY DURING THE AFTERNOON HOURS. THUNDERSTORMS
WILL BE CAPABLE OF BRIEF HEAVY RAIN AND POSSIBLY SOME GUSTY
WINDS...PENDING THE DEGREE OF INSTABILITY.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 324 AM EDT SAT SEP 20 2014
A QUICK MOVING COLD FRONT WILL BE EXITING THE REGION AS OF 0Z MONDAY.
MODELS CONTINUE TO COME INTO A BETTER AGREEMENT FOR THE ENDING TIME
OF PRECIP ASSOCIATED WITH THE FRONT...WITH THE NW EXPECTED TO CLEAR
OUT BY 0Z...AND FINALLY THE SE JUST AFTER 6Z MONDAY. LATEST FORECAST
SOUNDINGS ARE STILL ONLY SUPPORTING MARGINAL INSTABILITY FOR THE
PRECIP ACCOMPANYING THIS FRONT...QUICKLY DISSIPATING AS WE LOSE
DAYTIME HEATING...AND ONCE THE FRONTAL BOUNDARY HAS PASSED. AS
SUCH...THUNDER WAS MENTIONED IN PREVIOUS FORECAST PAST 0Z...AND HAS
ALSO BEEN INCLUDED BY SURROUNDING OFFICES THROUGH THE FIRST PART OF
THE EVENING. DID NOT FEEL CONFIDENT ENOUGH TO YANK MENTION OF THUNDER
COMPLETELY AT 0Z...SO KEPT MENTION OF SLIGHT CHANCE THUNDER WITH
CHANCE POPS THROUGH 3Z...WHICH CONSEQUENTLY IS ABOUT THE SAME TIME
CHANCE POPS EXIT THE REGION ANYWAYS. THERE IS SOME CONCERN THAT THE
COMBINATION OF STRONG SUBSIDENCE BEHIND THE FRONT...IN ADDITION TO
THE LINGERING MOISTURE ACROSS THE REGION...WILL LEAD TO A WIDESPREAD
FOG EVENT BY LATE SUNDAY NIGHT...OR PERHAPS A LOW STRATUS EVENT. THE
EXTENT OF EITHER OF THESE IS STILL SOMEWHAT UNCERTAIN. DECIDED TO
INCREASE CLOUDS SLIGHTLY OVERNIGHT SUNDAY NIGHT/MONDAY MORNING...BUT
DID NOT MENTION FOG AT THIS TIME.
AS THE FRONT QUICKLY DEPARTS SUNDAY EVENING/NIGHT...KY WILL FIND
ITSELF ON THE BACKSIDE OF THE UPPER LEVEL TROUGHING PATTERN...WITH
STRONG NW FLOW BRINGING MUCH COOLER CANADIAN AIR INTO THE REGION. AS
HIGH PRESSURE TAKES HOLD...DRY AND SUNNY SKIES WILL PREVAIL DURING
THE DAY MONDAY...BUT HIGH TEMPERATURES WILL STRUGGLE TO MAKE IT TO
THE 70 DEGREE MARK. AIRMASS MODIFICATION...NAMELY THE LESSENING OF
STRONG PRESSURE GRADIENT/NW FLOW AS THE UPPER LEVEL RIDGE TAKES FULL
CONTROL...WILL SLOWLY ALLOW TEMPS TO RISE THROUGHOUT THE REMAINDER
OF THE EXTENDED FORECAST PERIOD. HOWEVER WE LIKELY WON/T SEE TEMPS
HIT ABOVE THE 80 DEGREE MARK AGAIN UNTIL AT LEAST NEXT WEEKEND.
MEANWHILE...WITH SUCH STRONG SUBSIDENCE IN CONTROL...THERE WILL BE
LITTLE CONCERN FOR CLOUDS...LET ALONE PRECIP CHANCES. ALL IN ALL IT
LOOKS TO BE A GORGEOUS AUTUMN-LIKE WEEK AHEAD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 748 AM EDT SAT SEP 20 2014
ASIDE FROM ANY LINGERING VALLEY FOG LIFTING AND DISSIPATING THROUGH
13Z TO 14Z...VFR CONDITIONS WITH LIGHT WINDS WILL PREVAIL DURING THE
PERIOD. A COLD FRONT AND APPROACHING UPPER LEVEL SYSTEM WILL BRING
AN INCREASE IN CLOUDS LATER IN THE PERIOD...AND ISOLATED SHOWERS OR
PERHAPS A THUNDERSTORM COULD AFFECT AREAS NORTH OF A SME TO LOZ TO
JKL TO SJS LINE VERY LATE IN THE PERIOD. A FEW VALLEY LOCATIONS MAY
AGAIN EXPERIENCE FOG BETWEEN 3Z AND 12Z WITH VIS RESTRICTIONS DOWN TO
IFR OR MVFR...BUT THIS SHOULD NOT AFFECT THE TAF SITES.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...JP
LONG TERM...JMW
AVIATION...JP
AREA FORECAST DISCUSSION
NWS JACKSON KY
413 AM EDT SAT SEP 20 2014
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 355 AM EDT SAT SEP 20 2014
EARLY THIS MORNING...AN UPPER LEVEL RIDGE OF HIGH PRESSURE CENTERED
OVER THE SOUTHERN ROCKIES TO SOUTHERN PLAINS REGION WITH RIDGING EAST
INTO THE LOWER OH VALLEY WAS IN PLACE. ACROSS THE SOUTHEASTERN US...
A BROAD UPPER LEVEL LOW WAS PRESENT. MEANWHILE A SERIES OF SHORTWAVES
WERE IN THE NORTHERN STREAM WITH A WEAK LEAD SHORTWAVE NEAR THE MID
MS VALLEY REGION WITH ANOTHER SHORTWAVE NEARING THE NORTHERN GREAT
LAKES EXTENDING FROM WESTERN ONTARIO INTO THE UPPER MIDWEST AND DOWN
INTO THE CENTRAL PLAINS REGION. FURTHER NORTHWEST ANOTHER SHORTWAVE
IS MOVING ACROSS THE CANADIAN PLAINS.
THROUGH THE SHORT TERM PERIOD...THE LEAD WEAK SHORTWAVE WILL WORK
ACROSS THE AREA THROUGH EARLY TO MID AFTERNOON AS HEIGHTS BEGIN TO
FALL IN THE OH VALLEY REGION WHILE THE UPPER LEVEL RIDGE BUILDING
NORTH ACROSS THE ROCKIES AND INTO THE INTERIOR NORTHWESTERN US.
DOWNSTREAM ACROSS THE GREAT LAKES AND EASTERN US...A TROUGH OF LOW
PRESSURE WILL BEGIN TO BE CARVED OUT BY THE TWO MAIN SHORTWAVES AND
SOUTHEASTERN CONUS TROUGH BEGINNING TO MERGE INTO IT. THE ASSOCIATED
SFC LOW WILL TRACK WELL NORTH OF KY...BUT THE TRAILING COLD FRONT
WILL WORK INTO THE LOWER OH VALLEY REGION TONIGHT AND THEN MOVE
ACROSS THE COMMONWEALTH THROUGH THE END OF THE PERIOD...WHEN IT
SHOULD BE CLOSE TO EXITING INTO VA.
SCATTERED TO BROKEN CLOUDS IN THE 4 TO 7KFT RANGE HAVE DEVELOPED
OVERNIGHT IN THE WARM SECTOR. OUTSIDE OF THESE CLOUDS VALLEY FOG IS
LIKELY STILL PRESENT AND MAY BE DENSE AT LEAST IN SOME SPOTS ALONG THE
RIVERS AND LARGER STREAMS AND LAKES. DEWPOINT DEPRESSIONS ARE LARGER
NEARER TO THE VA BORDER WHERE A DOWNSLOPE FLOW HAS BEEN PRESENT WITH
SPEEDS OF 10 MPH OR MORE ACROSS THE HIGH TERRAIN AND OBSERVATIONS
SUPPORT ANY FOG BEING MUCH MORE LOCALIZED THERE. THIS FOG SHOULD
GRADUALLY BEGIN TO LIFT THROUGH SUNRISE AND THEN DISSIPATE BY A
COUPLE OF HOURS AFTER SUNRISE. IN ADDITION...WHERE CLOUDS FORM THIS
FOG WILL TEND TO DISSIPATE AS WELL.
THE MODEL GUIDANCE BRINGS THE WEAK MID LEVEL DISTURBANCE TOWARD THE
AREA FOR THE REMAINDER OF THE NIGHT AND INTO THE EARLY AFTERNOON.
THE 0Z NAM AND SOME OF THE NEAR TERM GUIDANCE SUCH AS THE HRRR ALSO
DEVELOP SOME CONVECTION THIS MORNING THROUGH EARLY AFTERNOON MAINLY
ACROSS THE WESTERN HALF OF THE CWA. MOS GUIDANCE ACROSS THESE
LOCATIONS DOES NOT HAVE A SLIGHT CHANCE POPS AND MODEL CONSENSUS
BLENDS GENERALLY STAYED BELOW SLIGHT AS WELL. HOWEVER...WE OPTED TO
GO WITH SLIGHT CHANCE IN THESE WESTERN LOCATIONS FOR TODAY...WHICH
WAS IN BETTER AGREEMENT WITH SURROUNDING WFOS.
THE MAIN PRECIPITATION CHANCE DURING THE SHORT TERM PERIOD AND THE
ENTIRE FORECAST PERIOD FOR THAT MATTER WILL COME AS THE TROUGH
BEGINS TO TAKE SHAPE LATE TONIGHT INTO THE DAY ON SUNDAY AND THE COLD
FRONT ENTERS EASTERN KY. THIS COLD FRONT AND THE APPROACHING TROUGH
IS EXPECTED TO BRING A BAND OF SCATTERED OR BETTER COVERAGE OF
CONVECTION AS IT WILL BE MOVING ACROSS EASTERN KY DURING THE DAYTIME.
ISOLATED TO SCATTERED CONVECTION MAY REACH THE NORTHERN PART OF THE
CWA TOWARD DAWN...BUT THE BEST CHANCE FOR CONVECTION WILL BE CLOSER
TO THE COLD FRONT GENERALLY DURING THE AFTERNOON HOURS. THUNDERSTORMS
WILL BE CAPABLE OF BRIEF HEAVY RAIN AND POSSIBLY SOME GUSTY
WINDS...PENDING THE DEGREE OF INSTABILITY.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 324 AM EDT SAT SEP 20 2014
A QUICK MOVING COLD FRONT WILL BE EXITING THE REGION AS OF 0Z MONDAY.
MODELS CONTINUE TO COME INTO A BETTER AGREEMENT FOR THE ENDING TIME
OF PRECIP ASSOCIATED WITH THE FRONT...WITH THE NW EXPECTED TO CLEAR
OUT BY 0Z...AND FINALLY THE SE JUST AFTER 6Z MONDAY. LATEST FORECAST
SOUNDINGS ARE STILL ONLY SUPPORTING MARGINAL INSTABILITY FOR THE
PRECIP ACCOMPANYING THIS FRONT...QUICKLY DISSIPATING AS WE LOSE
DAYTIME HEATING...AND ONCE THE FRONTAL BOUNDARY HAS PASSED. AS
SUCH...THUNDER WAS MENTIONED IN PREVIOUS FORECAST PAST 0Z...AND HAS
ALSO BEEN INCLUDED BY SURROUNDING OFFICES THROUGH THE FIRST PART OF
THE EVENING. DID NOT FEEL CONFIDENT ENOUGH TO YANK MENTION OF THUNDER
COMPLETELY AT 0Z...SO KEPT MENTION OF SLIGHT CHANCE THUNDER WITH
CHANCE POPS THROUGH 3Z...WHICH CONSEQUENTLY IS ABOUT THE SAME TIME
CHANCE POPS EXIT THE REGION ANYWAYS. THERE IS SOME CONCERN THAT THE
COMBINATION OF STRONG SUBSIDENCE BEHIND THE FRONT...IN ADDITION TO
THE LINGERING MOISTURE ACROSS THE REGION...WILL LEAD TO A WIDESPREAD
FOG EVENT BY LATE SUNDAY NIGHT...OR PERHAPS A LOW STRATUS EVENT. THE
EXTENT OF EITHER OF THESE IS STILL SOMEWHAT UNCERTAIN. DECIDED TO
INCREASE CLOUDS SLIGHTLY OVERNIGHT SUNDAY NIGHT/MONDAY MORNING...BUT
DID NOT MENTION FOG AT THIS TIME.
AS THE FRONT QUICKLY DEPARTS SUNDAY EVENING/NIGHT...KY WILL FIND
ITSELF ON THE BACKSIDE OF THE UPPER LEVEL TROUGHING PATTERN...WITH
STRONG NW FLOW BRINGING MUCH COOLER CANADIAN AIR INTO THE REGION. AS
HIGH PRESSURE TAKES HOLD...DRY AND SUNNY SKIES WILL PREVAIL DURING
THE DAY MONDAY...BUT HIGH TEMPERATURES WILL STRUGGLE TO MAKE IT TO
THE 70 DEGREE MARK. AIRMASS MODIFICATION...NAMELY THE LESSENING OF
STRONG PRESSURE GRADIENT/NW FLOW AS THE UPPER LEVEL RIDGE TAKES FULL
CONTROL...WILL SLOWLY ALLOW TEMPS TO RISE THROUGHOUT THE REMAINDER
OF THE EXTENDED FORECAST PERIOD. HOWEVER WE LIKELY WON/T SEE TEMPS
HIT ABOVE THE 80 DEGREE MARK AGAIN UNTIL AT LEAST NEXT WEEKEND.
MEANWHILE...WITH SUCH STRONG SUBSIDENCE IN CONTROL...THERE WILL BE
LITTLE CONCERN FOR CLOUDS...LET ALONE PRECIP CHANCES. ALL IN ALL IT
LOOKS TO BE A GORGEOUS AUTUMN-LIKE WEEK AHEAD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 150 AM EDT SAT SEP 20 2014
ASIDE FROM VALLEY FOG DEVELOPING...AND THEN LIFTING AND DISSIPATING
THROUGH 13Z TO 14Z...VFR CONDITIONS WITH LIGHT WINDS WILL PREVAIL
DURING THE PERIOD. A COLD FRONT AND ASSOCIATED INCREASE IN CLOUDS IS
EXPECTED LATE IN THE PERIOD. THE FOG IS AGAIN EXPECTED TO FOLLOW ITS
TYPICAL LATE SUMMER/EARLY AUTUMN PATTERN OF DEVELOPING FIRST IN DEEP
VALLEYS AND THEN GROWING IN BREADTH AND DEPTH...WITH THE POTENTIAL TO
BEGIN TO REACH SOME RIDGES AND OPEN TERRAIN BY DAWN...SUCH AS MVFR AT
SJS IF WINDS SLACKEN AND POSSIBLY MVFR AT SME WHERE THE CURRENT
DEWPOINT DEPRESSION IS LOW BUT THERE ARE SCT CLOUDS AS WELL. THE
LARGER RECENT OBSERVED DEWPOINT DEPRESSION OF 7 AT LOZ POINTS TOWARD
ANY FOG THAT DEVELOPS BEING IN THE VFR RANGE.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JP
LONG TERM...JMW
AVIATION...JP
AREA FORECAST DISCUSSION
NWS JACKSON KY
325 AM EDT SAT SEP 20 2014
.UPDATE...
ISSUED AT 140 AM EDT SAT SEP 20 2014
HOURLY GRIDS HAVE BEEN FRESHENED UP BASED ON RECENT OBSERVATIONS AND
TRENDS. THIS LED TO SLIGHTLY COLDER MIN T IN A COUPLE OF SPOTS ACROSS
THE NORTH...WITH THE MAIN CHANGE BEING MORE FOG IN THE GRIDS FOR
VALLEY LOCATIONS OUTSIDE OF THE HIGHEST TERRAIN WHERE THE PRESSURE
GRADIENT WAS WEAKER. WE HAVE RECEIVED A SPOTTER REPORT OF DENSE FOG
NEAR THE RED RIVER IN POWELL COUNTY AND 11-3.9 SAT IMAGERY SUPPORTS
VALLEY FOG AT PRESENT IN PARTS OF THE LIKING...BIG SANDY...KENTUCKY
AND RED RIVER VALLEYS. SOME OF THE FOG SHOULD AGAIN BE DENSE
GENERALLY ALONG THE LARGER CREEKS AND STREAMS AND ESPECIALLY RIVERS
AND LARGER LAKES. THE PRESSURE GRADIENT IS EXPECTED TO RELAX A BIT
OVERNIGHT ACROSS THE SOUTHEAST PART OF THE CWA SO OUTSIDE OF WHERE
SOME CLOUDS DEVELOP IN THE WARM SECTOR...VALLEY FOG SHOULD ALSO
DEVELOP THERE TOWARD DAWN.
SOME OF THE GUIDANCE INDICATES THE POTENTIAL FOR A FEW STRAY SHOWERS
AS A WEAK DISTURBANCE APPROACHES...MAINLY ACROSS THE WESTERN AND
NORTHWESTERN PARTS OF THE CWA LATER TONIGHT INTO EARLY ON SATURDAY.
CONFIDENCE IN THIS IS NOT ALL THAT HIGH...BUT IT DOES HAVE SUPPORT
FROM THE NAM...SOME OF THE RECENT HRRR RUNS AND SOME PRIOR BUT NOT
THE MOST RECENT RAP RUN. WE WILL CONTINUE TO EVALUATE THIS POTENTIAL
FOR THE SCHEDULED MORNING FORECAST RELEASE.
UPDATE ISSUED AT 1027 PM EDT FRI SEP 19 2014
USED OBSERVED TEMPERATURES AND DEW POINTS TO ADJUST HOURLY GRIDS FOR
TONIGHT...BLENDING TOWARD THE PREEXISTING FORECAST BY MORNING. NO
SUBSTANTIVE CHANGES TO THE OVERALL FORECAST WERE MADE.
UPDATE ISSUED AT 729 PM EDT FRI SEP 19 2014
HAVE UPDATED TO ALLOW FOR A FASTER DROP IN VALLEY TEMPS THIS
EVENING. ALSO...REDUCED SKY COVER FOR MOST AREAS THIS EVENING.
MESOSCALE MODELS ARE PERSISTENT IN SHOWING CLOUDS DEVELOPING NEAR OUR
WESTERN BORDER LATE TONIGHT INTO SATURDAY MORNING...A WELL AS SOME
SHOWERS. HAVE ACCOUNTED FOR A FEW CLOUDS...BUT KEPT THE FORECAST IN
THE JKL FORECAST AREA DRY AT THIS POINT.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 307 PM EDT FRI SEP 19 2014
A LARGE DOME OF HIGH PRESSURE WILL REMAIN ANCHORED OVER THE EAST
COAST INTO THE WEEKEND...PROVIDING A DRY START TO THE WEEKEND. STILL
A REMOTE CHANCE OF AN ISOLATED SHOWER ACROSS PIKE COUNTY LATER THIS
EVENING...BUT CHANCES SEEM TO BE DIMINISHING WITH EVERY HOUR THAT
PASSES. THE CU JUST DOES NOT LOOK ALL THAT IMPRESSIVE.
REGARDLESS...UNTIL INSTABILITY WANES THIS EVENING CANNOT RULE OUT A
BRIEF POP UP SHOWER. SKIES WILL CLEAR OUT AGAIN TONIGHT. WITH
DEW POINTS CLIMBING HIGHER TODAY...AND CLEARING SKIES...ANOTHER NIGHT
OF FOG CAN BE EXPECTED ACROSS THE AREA. SHOULD BE A FAIRLY TYPICAL
FOG FOR THIS TIME OF YEAR. HIGHS WILL CLIMB TO THE HIGHEST READINGS
OF THE WEEK ON SATURDAY AS TEMPERATURES CLIMB INTO THE LOW 80S DURING
THE AFTERNOON. CLOUDS WILL BE ON THE INCREASE SATURDAY NIGHT AS A
COLD FRONT PUSHES SOUTH INTO THE OHIO RIVER VALLEY. PRECIPITATION
ASSOCIATED WITH THIS BOUNDARY COULD MAKE IT INTO AREAS NORTH OF 1-64
PRIOR TO 12Z SUNDAY...BUT IT APPEARS THE MAIN PRECIPITATION WITH THE
FRONT SHOULD COME COME LATER ON SUNDAY. WITH CLOUDS AND SURFACE
MOISTURE INCREASING SATURDAY NIGHT...A MILDER NIGHT IS ON TAP WITH
LOWS ONLY INTO THE 60S.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 324 AM EDT SAT SEP 20 2014
A QUICK MOVING COLD FRONT WILL BE EXITING THE REGION AS OF 0Z MONDAY.
MODELS CONTINUE TO COME INTO A BETTER AGREEMENT FOR THE ENDING TIME
OF PRECIP ASSOCIATED WITH THE FRONT...WITH THE NW EXPECTED TO CLEAR
OUT BY 0Z...AND FINALLY THE SE JUST AFTER 6Z MONDAY. LATEST FORECAST
SOUNDINGS ARE STILL ONLY SUPPORTING MARGINAL INSTABILITY FOR THE
PRECIP ACCOMPANYING THIS FRONT...QUICKLY DISSIPATING AS WE LOSE
DAYTIME HEATING...AND ONCE THE FRONTAL BOUNDARY HAS PASSED. AS
SUCH...THUNDER WAS MENTIONED IN PREVIOUS FORECAST PAST 0Z...AND HAS
ALSO BEEN INCLUDED BY SURROUNDING OFFICES THROUGH THE FIRST PART OF
THE EVENING. DID NOT FEEL CONFIDENT ENOUGH TO YANK MENTION OF THUNDER
COMPLETELY AT 0Z...SO KEPT MENTION OF SLIGHT CHANCE THUNDER WITH
CHANCE POPS THROUGH 3Z...WHICH CONSEQUENTLY IS ABOUT THE SAME TIME
CHANCE POPS EXIT THE REGION ANYWAYS. THERE IS SOME CONCERN THAT THE
COMBINATION OF STRONG SUBSIDENCE BEHIND THE FRONT...IN ADDITION TO
THE LINGERING MOISTURE ACROSS THE REGION...WILL LEAD TO A WIDESPREAD
FOG EVENT BY LATE SUNDAY NIGHT...OR PERHAPS A LOW STRATUS EVENT. THE
EXTENT OF EITHER OF THESE IS STILL SOMEWHAT UNCERTAIN. DECIDED TO
INCREASE CLOUDS SLIGHTLY OVERNIGHT SUNDAY NIGHT/MONDAY MORNING...BUT
DID NOT MENTION FOG AT THIS TIME.
AS THE FRONT QUICKLY DEPARTS SUNDAY EVENING/NIGHT...KY WILL FIND
ITSELF ON THE BACKSIDE OF THE UPPER LEVEL TROUGHING PATTERN...WITH
STRONG NW FLOW BRINGING MUCH COOLER CANADIAN AIR INTO THE REGION. AS
HIGH PRESSURE TAKES HOLD...DRY AND SUNNY SKIES WILL PREVAIL DURING
THE DAY MONDAY...BUT HIGH TEMPERATURES WILL STRUGGLE TO MAKE IT TO
THE 70 DEGREE MARK. AIRMASS MODIFICATION...NAMELY THE LESSENING OF
STRONG PRESSURE GRADIENT/NW FLOW AS THE UPPER LEVEL RIDGE TAKES FULL
CONTROL...WILL SLOWLY ALLOW TEMPS TO RISE THROUGHOUT THE REMAINDER
OF THE EXTENDED FORECAST PERIOD. HOWEVER WE LIKELY WON/T SEE TEMPS
HIT ABOVE THE 80 DEGREE MARK AGAIN UNTIL AT LEAST NEXT WEEKEND.
MEANWHILE...WITH SUCH STRONG SUBSIDENCE IN CONTROL...THERE WILL BE
LITTLE CONCERN FOR CLOUDS...LET ALONE PRECIP CHANCES. ALL IN ALL IT
LOOKS TO BE A GORGEOUS AUTUMN-LIKE WEEK AHEAD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 150 AM EDT SAT SEP 20 2014
ASIDE FROM VALLEY FOG DEVELOPING...AND THEN LIFTING AND DISSIPATING
THROUGH 13Z TO 14Z...VFR CONDITIONS WITH LIGHT WINDS WILL PREVAIL
DURING THE PERIOD. A COLD FRONT AND ASSOCIATED INCREASE IN CLOUDS IS
EXPECTED LATE IN THE PERIOD. THE FOG IS AGAIN EXPECTED TO FOLLOW ITS
TYPICAL LATE SUMMER/EARLY AUTUMN PATTERN OF DEVELOPING FIRST IN DEEP
VALLEYS AND THEN GROWING IN BREADTH AND DEPTH...WITH THE POTENTIAL TO
BEGIN TO REACH SOME RIDGES AND OPEN TERRAIN BY DAWN...SUCH AS MVFR AT
SJS IF WINDS SLACKEN AND POSSIBLY MVFR AT SME WHERE THE CURRENT
DEWPOINT DEPRESSION IS LOW BUT THERE ARE SCT CLOUDS AS WELL. THE
LARGER RECENT OBSERVED DEWPOINT DEPRESSION OF 7 AT LOZ POINTS TOWARD
ANY FOG THAT DEVELOPS BEING IN THE VFR RANGE.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...KAS
LONG TERM...JMW
AVIATION...JP
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
155 AM EDT SAT SEP 20 2014
.UPDATE...
ISSUED AT 140 AM EDT SAT SEP 20 2014
HOURLY GRIDS HAVE BEEN FRESHENED UP BASED ON RECENT OBSERVATIONS AND
TRENDS. THIS LED TO SLIGHTLY COLDER MIN T IN A COUPLE OF SPOTS ACROSS
THE NORTH...WITH THE MAIN CHANGE BEING MORE FOG IN THE GRIDS FOR
VALLEY LOCATIONS OUTSIDE OF THE HIGHEST TERRAIN WHERE THE PRESSURE
GRADIENT WAS WEAKER. WE HAVE RECEIVED A SPOTTER REPORT OF DENSE FOG
NEAR THE RED RIVER IN POWELL COUNTY AND 11-3.9 SAT IMAGERY SUPPORTS
VALLEY FOG AT PRESENT IN PARTS OF THE LIKING...BIG SANDY...KENTUCKY
AND RED RIVER VALLEYS. SOME OF THE FOG SHOULD AGAIN BE DENSE
GENERALLY ALONG THE LARGER CREEKS AND STREAMS AND ESPECIALLY RIVERS
AND LARGER LAKES. THE PRESSURE GRADIENT IS EXPECTED TO RELAX A BIT
OVERNIGHT ACROSS THE SOUTHEAST PART OF THE CWA SO OUTSIDE OF WHERE
SOME CLOUDS DEVELOP IN THE WARM SECTOR...VALLEY FOG SHOULD ALSO
DEVELOP THERE TOWARD DAWN.
SOME OF THE GUIDANCE INDICATES THE POTENTIAL FOR A FEW STRAY SHOWERS
AS A WEAK DISTURBANCE APPROACHES...MAINLY ACROSS THE WESTERN AND
NORTHWESTERN PARTS OF THE CWA LATER TONIGHT INTO EARLY ON SATURDAY.
CONFIDENCE IN THIS IS NOT ALL THAT HIGH...BUT IT DOES HAVE SUPPORT
FROM THE NAM...SOME OF THE RECENT HRRR RUNS AND SOME PRIOR BUT NOT
THE MOST RECENT RAP RUN. WE WILL CONTINUE TO EVALUATE THIS POTENTIAL
FOR THE SCHEDULED MORNING FORECAST RELEASE.
UPDATE ISSUED AT 1027 PM EDT FRI SEP 19 2014
USED OBSERVED TEMPERATURES AND DEW POINTS TO ADJUST HOURLY GRIDS FOR
TONIGHT...BLENDING TOWARD THE PREEXISTING FORECAST BY MORNING. NO
SUBSTANTIVE CHANGES TO THE OVERALL FORECAST WERE MADE.
UPDATE ISSUED AT 729 PM EDT FRI SEP 19 2014
HAVE UPDATED TO ALLOW FOR A FASTER DROP IN VALLEY TEMPS THIS
EVENING. ALSO...REDUCED SKY COVER FOR MOST AREAS THIS EVENING.
MESOSCALE MODELS ARE PERSISTENT IN SHOWING CLOUDS DEVELOPING NEAR OUR
WESTERN BORDER LATE TONIGHT INTO SATURDAY MORNING...A WELL AS SOME
SHOWERS. HAVE ACCOUNTED FOR A FEW CLOUDS...BUT KEPT THE FORECAST IN
THE JKL FORECAST AREA DRY AT THIS POINT.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 307 PM EDT FRI SEP 19 2014
A LARGE DOME OF HIGH PRESSURE WILL REMAIN ANCHORED OVER THE EAST
COAST INTO THE WEEKEND...PROVIDING A DRY START TO THE WEEKEND. STILL
A REMOTE CHANCE OF AN ISOLATED SHOWER ACROSS PIKE COUNTY LATER THIS
EVENING...BUT CHANCES SEEM TO BE DIMINISHING WITH EVERY HOUR THAT
PASSES. THE CU JUST DOES NOT LOOK ALL THAT IMPRESSIVE.
REGARDLESS...UNTIL INSTABILITY WANES THIS EVENING CANNOT RULE OUT A
BRIEF POP UP SHOWER. SKIES WILL CLEAR OUT AGAIN TONIGHT. WITH
DEW POINTS CLIMBING HIGHER TODAY...AND CLEARING SKIES...ANOTHER NIGHT
OF FOG CAN BE EXPECTED ACROSS THE AREA. SHOULD BE A FAIRLY TYPICAL
FOG FOR THIS TIME OF YEAR. HIGHS WILL CLIMB TO THE HIGHEST READINGS
OF THE WEEK ON SATURDAY AS TEMPERATURES CLIMB INTO THE LOW 80S DURING
THE AFTERNOON. CLOUDS WILL BE ON THE INCREASE SATURDAY NIGHT AS A
COLD FRONT PUSHES SOUTH INTO THE OHIO RIVER VALLEY. PRECIPITATION
ASSOCIATED WITH THIS BOUNDARY COULD MAKE IT INTO AREAS NORTH OF 1-64
PRIOR TO 12Z SUNDAY...BUT IT APPEARS THE MAIN PRECIPITATION WITH THE
FRONT SHOULD COME COME LATER ON SUNDAY. WITH CLOUDS AND SURFACE
MOISTURE INCREASING SATURDAY NIGHT...A MILDER NIGHT IS ON TAP WITH
LOWS ONLY INTO THE 60S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 322 PM EDT FRI SEP 19 2014
ALL OF THE WEATHER IS AT THE FRONT END OF THIS FORECAST PERIOD AS A
COLD FRONT IS SET TO SWEEP QUICKLY ACROSS THE AREA ON SUNDAY.
MOISTURE RETURN IN ADVANCE OF THE FRONT IS NOT GREAT WITH PWATS ONLY
CREEPING UP TO ABOUT 1.5 INCHES IN A THIN RIBBON. COUPLED WITH ONLY
WEAK INSTABILITY...ANTICIPATE A NARROW BAND OF SHOWERS AND A FEW
THUNDERSTORMS TO ACCOMPANY THE FRONT DURING THE DAY ON SUNDAY. THE
BULK OF THIS ACTIVITY SHOULD BE TO OUR SOUTHEAST BY SUNDAY EVENING.
FOLLOWING THIS FRONTAL PASSAGE...A LARGE DOME OF HIGH PRESSURE WILL
SLIDE ACROSS THE OHIO VALLEY. COUPLED WITH A BUILDING RIDGE ALOFT...
THIS SHOULD RESULT IN A PROLONGED PERIOD OF DRY WEATHER WITH
PLEASANT TEMPERATURES NEXT WEEK. THERE IS ONE POSSIBLE FLY IN THE
OINTMENT THOUGH AS FORECAST MODELS HINT THAT A WEAK UPPER LOW MAY
GET TRAPPED TO THE SOUTH OF THE UPPER RIDGE. ALL SIGNS CURRENTLY ARE
THAT ANY ASSOCIATED MOISTURE WITH THIS LOW WOULD STAY TO OUR SOUTH
AND EAST SO WILL NOT GIVE THIS ANY PLAY IN OUR LOCAL FORECAST AT
THIS TIME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 150 AM EDT SAT SEP 20 2014
ASIDE FROM VALLEY FOG DEVELOPING...AND THEN LIFTING AND DISSIPATING
THROUGH 13Z TO 14Z...VFR CONDITIONS WITH LIGHT WINDS WILL PREVAIL
DURING THE PERIOD. A COLD FRONT AND ASSOCIATED INCREASE IN CLOUDS IS
EXPECTED LATE IN THE PERIOD. THE FOG IS AGAIN EXPECTED TO FOLLOW ITS
TYPICAL LATE SUMMER/EARLY AUTUMN PATTERN OF DEVELOPING FIRST IN DEEP
VALLEYS AND THEN GROWING IN BREADTH AND DEPTH...WITH THE POTENTIAL TO
BEGIN TO REACH SOME RIDGES AND OPEN TERRAIN BY DAWN...SUCH AS MVFR AT
SJS IF WINDS SLACKEN AND POSSIBLY MVFR AT SME WHERE THE CURRENT
DEWPOINT DEPRESSION IS LOW BUT THERE ARE SCT CLOUDS AS WELL. THE
LARGER RECENT OBSERVED DEWPOINT DEPRESSION OF 7 AT LOZ POINTS TOWARD
ANY FOG THAT DEVELOPS BEING IN THE VFR RANGE.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...KAS
LONG TERM...ABE
AVIATION...JP
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
314 PM EDT SAT SEP 20 2014
.SHORT TERM...THIS AFTERNOON AND TONIGHT
SEVERAL OUTFLOW BOUNDARIES FROM OVERNIGHT CONVECTION WELL TO THE
WEST ARE TRACKING ACROSS LOWER MICHIGAN. HOWEVER...18Z DTX SOUNDING
SHOWS A RATHER ROBUST CAP IN THE 875-850MB AREA...WHICH WILL LIKELY
TAKE QUITE SOME TIME TO TOTALLY ERODE. MODELS...INCLUDING PRIMARY
AND PARALLEL HRRR RUNS TODAY...SUGGEST CONVECTION WILL EVENTUALLY
FILL IN ALONG BOTH OUTFLOW BOUNDARY SINKING SOUTH/SOUTHEAST THROUGH
THE CWA AND ALSO ALONG VORTICITY SPOKE FURTHER WEST ASSOCIATED WITH
LEFTOVER WEAK MCV. GIVEN CAPPING...AND THE LACK OF SIGNIFICANT
INSTABILITY...EXPECT THIS ACTIVITY TO REMAIN RATHER DISORGANIZED AND
SUB-SEVERE FOR THE MOST PART.
WILL STILL WATCH FOR THE POTENTIAL OF A FEW SEVERE STORMS AS WIND
FIELDS ARE DECENT...INCREASING FROM 25-30 KNOTS H85-H7 TO 50 KNOTS
AT H5. WITH ADDITIONAL HEATING...TEMPERATURES AROUND 80F DETROIT
SOUTH...OVER THE SOUTHERN CWA AND A LACK OF NOTABLE DEEP LOW LEVEL
MOISTURE...INVERTED-V SOUNDINGS MAY ASSIST IN GUST POTENTIAL GIVEN
THE ABOVE ATMOSPHERIC WIND SPEEDS.
THIS INITIAL PUSH OF FORCING...AND WHATEVER CONVECTION COMES OF
IT...WILL SHIFT EAST/SOUTHEAST OF THE AREA LATE THIS AFTERNOON/EARLY
THIS EVENING. HOWEVER...HIGHER THETA-E AIR WILL CONTINUE TO SHIFT
OVER THE CWA...PARTICULARLY M 59 SOUTH...WITHIN SOUTHWEST FLOW IN
ADVANCE OF MAIN SHORTWAVE TROUGH AXIS. SO...ADDITIONAL SCATTERED
SHOWERS/EMBEDDED STORMS WILL BUILD THROUGH AREA INTO THIS EVENING.
ONCE THIS ACTIVITY EBBS LATE THIS EVENING...EXPECT RENEWED SHOWER
AND STORM DEVELOPMENT LATE TONIGHT AS MAIN UPPER LEVEL SHORTWAVE
DIGS FROM THE UPPER MISSISSIPPI VALLEY INTO THE CENTRAL GREAT LAKES.
WITH MILD...SOUTHWEST FLOW PERSISTING THROUGH THE NIGHT...MINIMUM
TEMPERATURES WILL BE RATHER MILD...HOLDING IN THE 60S IN MOST
LOCATIONS...ESPECIALLY AS FURTHER CLOUDS/PRECIPITATION PROVIDE
ADDITIONAL INSOLATION AND MINIMIZE RADIATIONAL COOLING FURTHER.
&&
.LONG TERM...
LATEST WATER VAPOR IMAGERY SHOWS A STRONG BUT PROGRESSIVE UPPER
LEVEL SYSTEM/CIRCULATION OVER SOUTHERN MANITOBA...WITH A STRONGER
EMBEDDED UPPER WAVE AT THE BASE OF THE TROUGH OVER NORTH DAKOTA. IT
IS THIS UPPER WAVE/COLD POOL (-18 TO -19 C) WHICH WILL ARRIVE OVER
SOUTHERN LOWER MICHIGAN SUNDAY MORNING. WITH SOME LEFTOVER LOW LEVEL
MOISTURE AND MORE THAN ADEQUATE MID LEVEL LAPSE RATE (6.5+ C/KM FROM
700-500 MB)...ADDITIONAL SHOWERS AND EMBEDDED THUNDERSTORMS APPEAR
LIKELY DURING SUNDAY. A SECONDARY UPPER WAVE/COLD POOL WILL FOLLOW
ON THE BACKSIDE THROUGH THE WESTERN GREAT LAKES AND INTO THE OHIO
VALLEY. DEEP NORTHERLY FLOW IN THIS SYSTEMS WAKE OVER THE CENTRAL
GREAT LAKES WILL ALLOW FOR SOLID COLD ADVECTION TO TAKE PLACE...AS
850 MB TEMPS LOWER INTO THE LOW SINGLE NUMBERS...WITH SLIGHTLY
NEGATIVE VALUES OVER LAKE HURON...PER 12Z EURO/NAM. AS SUCH...FULLY
ONBOARD WITH THE 12Z NAM 925 MB RH/LOW CLOUDS AS NORTHERLY FLOW
COMES OFF THE RELATIVELY WARM WATERS OF LAKE HURON SUNDAY NIGHT.
HAVE SUBSEQUENTLY RAMPED UP THE CLOUDS MONDAY MORNING...WHICH WILL
LIKELY TAKE MUCH OF THE DAY TO MIX OUT/ERODE...HOLDING MAXES CLOSE
TO 60 DEGREES. FAVORABLE RADIATING CONDITIONS MONDAY NIGHT EXPECTED
TO ALLOW MINS TO FALL INTO THE 40S.
STUBBORN HIGH PRESSURE AND RELENTLESS LOW RH VALUES THROUGH THE
COLUMN WILL REMAIN IN PLACE FOR THE ENTIRE EXTENDED PERIOD. FLOW
WILL CONTINUE TO BE WEAK UNDER AN OMEGA BLOCKING HIGH. TEMPERATURES
WILL TREND SLIGHTLY ABOVE NORMAL WITH NO THREAT OF PRECIPITATION.
&&
.MARINE...
WARMER AIRMASS AHEAD OF COLD FRONT...COUPLED WITH THE WEAKENING
PRESSURE GRADIENT AS THE FRONT APPROACHES IS TRANSLATING
TO WIND SPEEDS BELOW 25 KNOTS...AND WILL DROP THE SMALL CRAFT
ADVISORIES. HOWEVER...SHOWERS AND THUNDERSTORMS WILL LIKELY
DEVELOP...AND THUNDERSTORMS WILL BE STRONG TO POSSIBLY SEVERE INTO
TONIGHT. A SECONDARY UPPER WAVE AND COLD FRONT WILL LEAD TO
ADDITIONAL SHOWERS TOMORROW AND POSSIBLE THUNDERSTORMS. BRISK
NORTHERLY WINDS OF 20 TO 25 KNOTS WILL FOLLOW THIS FRONT...ALLOWING
LARGE WAVE TO BUILD OVER SOUTHERN LAKE HURON SUNDAY NIGHT INTO
MONDAY...WITH SMALL CRAFT ADVISORIES LIKELY NEED DURING THAT TIME
FRAME. HIGH PRESSURE WILL EXERT FAVORABLE INFLUENCE ON THE WATERS
DURING THE MIDDLE OF NEXT WEEK.
&&
.AVIATION...ISSUED 1251 PM EDT SAT SEP 20 2014
//DISCUSSION...
FORCING ALONG LEAD OUTFLOW BOUNDARY/WEAK MCV CENTER SHOULD BRING SCT
CONVECTION TO LOWER MICHIGAN BY 17Z-19Z...WELL AHEAD OF THE SYNOPTIC
TROUGH AXIS WEST OVER WISCONSIN. THIS ACTIVITY WILL ORGANIZE TO SOME
DEGREE AS IT MOVES INTO TERMINALS...BUT GIVEN THE EARLIER ARRIVAL OF
ACTIVITY...INSTABILITY WILL REMAIN LIMITED AS SURFACE DEW POINTS
STRUGGLE TOWARDS 60F IN ADVANCE OF THIS INITIAL ACTIVITY.
AFTER THIS PUSH OF SHRAS/EMBEDDED THUNDER...HIGHER THETA-E AIR WILL
CONTINUE TO FUNNEL INTO AREA IN ADVANCE OF MAIN TROUGH...LEADING TO
A CONTINUATION OF RATHER DISORGANIZED CONVECTION INTO THE EVENING
GENERALLY SOUTH OF M 59. RENEWED ACTIVITY CAN THEN BE EXPECTED BY
LATE TONIGHT/SUNDAY MORNING AS MAIN UPPER SHORTWAVE DIGS INTO THE
AREA...DURING WHICH TIME CIGS WILL CONSISTENTLY DROP TO MVFR OR
PERHAPS IFR AT TIMES.
//DTW THRESHOLD THREATS...
* LOW CONFIDENCE THAT A THUNDERSTORM WILL IMPACT KDTW BEYOND 22Z
THIS AFTERNOON.
* LOW CONFIDENCE IN CEILINGS BELOW 5000 FEET AFTER 22Z...WITH
PROGRESSIVELY HIGHER CONFIDENCE FROM TONIGHT INTO SUNDAY MORNING.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...
SMALL CRAFT ADVISORY...SAGINAW BAY AND THE NEARSHORE WATERS FROM
PORT AUSTIN TO HARBOR BEACH...UNTIL 8 PM SATURDAY.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.
&&
$$
SHORT TERM...DG
LONG TERM....SF/MM
MARINE.......SF
AVIATION.....DG
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DULUTH MN
612 PM CDT SUN SEP 21 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 301 PM CDT SUN SEP 21 2014
MOST OF THE CLOUDS HAVE DISSIPATED ACROSS THE CWA THIS
AFTERNOON...WITH A RIBBON OF THICKER CLOUDS REMAINING JUST WEST OF
THE NORTHLAND. THE RAP HAS BEEN CONSISTENT ON BRINGING SOME OF
THESE CLOUDS BACK INTO OUR WESTERN/NORTHERN ZONES TONIGHT. THERE
IS SOME EASTWARD MOVEMENT TOWARD KOOCHICHING COUNTY OVER THE LAST
SEVERAL SATELLITE IMAGES. WE HAVE DO BRING AN INCREASE IN CLOUDS
OVER PARTS OF THE WEST/NORTH TONIGHT.
HIGH PRESSURE WILL KEEP THE CWA DRY THROUGH MONDAY WITH MORE SUN
EXPECTED.
LOWS TONIGHT WILL DROP INTO THE UPPER THIRTIES TO LOWER FORTIES.
WE WENT ON THE LOW END OF GUIDANCE AND EVEN DROPPED TEMPS A BIT
MORE OVER PARTS OF OUR FAR NORTHEAST ZONES AND FROM KHYR TO KPBH.
LATER SHIFTS WILL HAVE TO MONITOR TEMPS CLOSELY AS IF THEY DROP A
BIT MORE THAN EXPECTED...SOME PATCHY FROST IS POSSIBLE. FOG WILL
ALSO BE POSSIBLE TONIGHT.
HIGHS MONDAY WILL BE SEVERAL DEGREES ABOVE NORMAL...AND RANGE FORM
THE MID SIXTIES TO AROUND SEVENTY.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 301 PM CDT SUN SEP 21 2014
DRY CONDITIONS EXPECTED EARLY IN THE WEEK WITH AN UPPER LEVEL RIDGE
BUILDING EWD ACROSS THE UPPER MIDWEST/WRN GREAT LAKES AREA. AT THE
SFC A 1025MB HIGH WILL TRANSLATE EWD THROUGH THE SRN GREAT LAKES. A
SLY FLOW WILL DEVELOP BEHIND THE DEPARTING HIGH AND AHEAD OF THE
NEXT INCOMING AREA OF LOW PRESSURE. THIS NEXT SYSTEM WILL TRACK FROM
THE ROCKIES THROUGH THE CENTRAL PLAINS DURING THE DAY TUESDAY. THE
MAIN FORCING WILL REMAIN ALOFT ASSOCIATED WITH THE UPPER LOW...WHICH
WILL RUN INTO A BLOCKING HIGH TO THE EAST AND LIFT TO THE NE THROUGH
NRN MN AND WRN LAKE SUPERIOR LATE TUE NIGHT AND THROUGH THE DAY WED.
RAIN SHOWERS WILL ACCOMPANY THIS SYSTEM...AND REMAIN CONFINED TO
AREAS NORTH OF MN HIGHWAY 210 AND EWD ALONG THE SOUTH SHORE IN NW
WI. RAINFALL AMTS ARE EXPECTED TO BE LIGHT. A BROAD HIGH AMPLITUDE
RE-ENFORCING UPPER LEVEL RIDGE IS EXPECTED TO BUILD THROUGH THE
CENTRAL U.S. ON THURSDAY...AND INTO THE GREAT LAKES BY FRIDAY. THIS
HIGH PRESSURE WILL KEEP CONDITIONS DRY AND WARM THROUGH FRIDAY AND
INTO THE WEEKEND. TEMPERATURES THROUGH THE WEEK WILL REMAIN
RELATIVELY WARM WITH HIGHS IN THE UPPER 60S AND 70S...AND OVERNIGHT
LOWS IN THE 50S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 612 PM CDT SUN SEP 21 2014
BATCH OF CLOUDS MAKING ITS MOVE OVER THE TERMINALS AT THE OUTSET
OF THE FORECAST. VFR CIGS ARE EXPECTED. STILL ANTICIPATING SOME BR
FORMATION AND KEPT TIMING AND VSBYS FROM PREVIOUS FORECAST. SOME
CU STILL FORECAST AFTER 13Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 44 69 48 70 / 0 0 0 0
INL 42 71 45 74 / 0 0 0 0
BRD 44 70 47 72 / 0 0 0 0
HYR 40 67 44 73 / 0 0 0 0
ASX 44 67 47 72 / 0 0 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...MELDE
LONG TERM...BJT
AVIATION...GSF
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1215 PM MDT SAT SEP 20 2014
.UPDATE...
QUICK UPDATE TO RAISE MAX TEMPS FOR THIS AFTERNOON IN THE NORTHEAST.
&&
.AVIATION...
18Z TAF CYCLE
STILL SOME IFR CIGS PERSISTING ROUGHLY SE OF A LINE FROM KSRR TO
KTCC. KROW WILL BE IMPACTED THE MOST...THOUGH SHOULD SEE IT WAFFLE
BTW SCT AND BKN OVER THE NEXT FEW HOURS. EASTERLY WINDS WILL
INCREASE AS THE AFTN PROGRESSES...ESPECIALLY BELOW GAPS AT KABQ
AND KSAF. MAY NEED TO ISSUE AN AWW LATER FOR KABQ FOR WIND GUSTS
GREATER THAN 35KT. OTHERWISE...SOME SPOTTY SHRA AND TSRA ACROSS
THE NORTH AND WEST THIS AFTN/EVE. CONFIDENCE IS ONLY HIGH ENOUGH
TO INCLUDE A VC MENTION AT THIS TIME AT KFMN...KGUP AND KSAF.
SHOULD SEE ANOTHER ROUND OF LIFR/IFR CIGS AND PERHAPS VSBYS AFT
06Z TONIGHT ALONG AND EAST OF THE CENTRAL MT CHAIN. MAY ALSO SEE
A FEW SHOWERS DEVELOP AROUND KROW NEAR SUNRISE SUNDAY.
34
&&
.PREV DISCUSSION...348 AM MDT SAT SEP 20 2014...
.SYNOPSIS...
VERY MOIST AIR MASS TO REMAIN IN PLACE ACROSS SOUTHEAST NEW MEXICO
WHERE SHOWERS AND A FEW THUNDERSTORMS ARE MOST FAVORED. DEEPER
MOISTURE WILL EXPAND WESTWARD LATE TODAY AND TONIGHT...WITH SHOWER
AND THUNDERSTORM ACTIVITY EXPECTED TO INCREASE AGAIN FOR PARTS OF
THE EASTERN PLAINS. AN OVERALL UPTICK IN SHOWER AND THUNDERSTORM
ACTIVITY IS EXPECTED FOR SUNDAY AND SUNDAY EVENING AS A
DISTURBANCE ALOFT PASSES JUST NORTH OF THE STATE AND HELPS TO DRAW
MOISTURE FARTHER NORTH AND WEST. DRIER AIR WILL THEN SPREAD
EASTWARD INTO NORTHWEST NEW MEXICO MONDAY AND MOST AREAS TUESDAY.
MEANWHILE... TEMPERATURES WILL REMAIN GENERALLY ABOVE NORMAL
ACROSS THE WEST AND BELOW NORMAL ACROSS THE EAST. BY THE MIDDLE OF
NEXT WEEK...A DRYING TREND WILL TAKE A STRONGER HOLD ON THE
AREA...AND TEMPERATURES WILL BE NEAR TO SLIGHTLY ABOVE NORMAL
EXCEPT FOR THE SOUTHEAST PLAINS WHERE COOLER THAN AVERAGE
TEMPERATURE WILL LIKELY LINGER.
&&
.DISCUSSION...
EXTENSIVE LOW CLOUDS AND AT LEAST PATCHY DENSE FOG EAST OF THE
CENTRAL MOUNTAIN CHAIN EARLY THIS MORNING. EXPECT FOG TO
DEVELOP/EXPAND AND HAVE GREATEST IMPACT ALONG THE IMMEDIATE EAST
SLOPES AND ALONG THE WESTERN FRINGES OF PERSISTENT STRATUS DECK.
VERY MOIST AIR MASS REMAINS IN PLACE ACROSS THE SOUTHEAST PLAINS
WHERE SURFACE DEW POINT TEMPS SOLIDLY IN THE MID/UPPER 60S. THUS
EVEN WEAK UPSLOPE/LOW LEVEL CONVERGENCE IN THIS ENVIRON ENOUGH TO
GENERATE ISOLATED ACTIVITY THIS MORNING...AND ALL INDICATIONS
POINT TOWARD A GRADUAL STRENGTHENING OF THE E-SE BOUNDARY LAYER
WINDS ACROSS THE PLAINS AS THE DAY PROGRESSES AND MORESO INTO THE
EVENING HOURS. LATEST 13KM RAPID REFRESH /RAP/ AND HRRR MODEL RUNS
CONTINUE TO SUPPORT ISO-SCT COVERAGE FOR THE EC/SE ZONES TODAY.
AND GOOD AGREEMENT BETWEEN GFS/NAM SUPPORTING PREVIOUS POP/WX
TRENDS INCREASING POP FOR SE 1/4 TONIGHT WITH A PREFERRED AXIS
ALONG/WEST OF THE PECOS RIVER VALLEY TO EAST SLOPES OF THE SC
MOUNTAINS WHERE UPSLOPE EFFECTS WILL BE MAXIMIZED.
OUTSIDE THE SC MTNS AND EC/SE PLAINS...A PREDOMINATELY DRY AND
UNSEASONABLY WARM FORECAST TODAY BENEATH GRADUALLY STRENGTHENING
HIGH PRESSURE ALOFT THAT SHOULD CENTER NEAR OR JUST NORTH OF THE
NM/CO LINE TODAY BEFORE DEFLATING AND SHIFTING EAST AND SOUTH
TONIGHT- SUNDAY. THE SLIGHT AMPLIFICATION OF THE RIDGE ALOFT TODAY
AND THEN TRENDS INTO SUNDAY DUE TO A CLOSED LOW FORECAST TO MOVE
INTO CENTRAL CA LATE TODAY- TONIGHT THEN ACROSS THE GREAT BASIN
SUNDAY. THE ONE EXCEPTION TO THE PREDOMINATELY DRY FORECAST TODAY
WILL BE CATRON COUNTY/UPPER GILA REGION EXTENDING NORTH TOWARD THE
ZUNI MOUNTAINS NEAR THE NM/AZ LINE WHERE MID LEVEL MOISTURE
EXPECTED TO ADVECT NORTHWARD IN THE DEVELOPING S-SELY FLOW. AN
EXPANSION OF ISOLATED TO SCATTERED POPS EXPECTED AREAWIDE BY
SUNDAY...ESPECIALLY THE NORTH AND WEST...AS FORCING FOR LARGE-
SCALE LIFT AIDS CONVECTION SUNDAY PM. SURFACE PRESSURE FALLS TO
THE WEST OF THE STATE ASSOCIATED WITH THE CA LOW PRESSURE SYSTEM
MOST LIKELY RESPONSIBLE FOR THE STRENGTHENING E-SELY BOUNDARY
LAYER LATE TODAY AND TONIGHT. THIS WILL BRING HIGHER DEW POINT AIR
WESTWARD CONTRIBUTING TO THE OVERALL IMPROVING SHRA/TSRA CHANCES.
STORM MOTIONS WILL BE FAIRLY FAST BUT COULD SEE A FEW STRONG CELLS
DEVELOP SUNDAY PM NW ZONES.
CLOSED LOW TO OPEN UP AND PASS NORTH OF THE STATE MONDAY...WITH
PROGRESSIVELY DRIER AIR MASS INTO THE FOUR CORNERS. BEST POPS FROM
NE TO SW. TRANSITION TO NWLY FLOW ALOFT ON TUESDAY THAT WOULD
FAVOR THE NC/NE AREAS BUT WITH RESIDUAL MOISTURE CANNOT RULE OUT
ISOLATED- SCATTERED SHRA/TSRA ACROSS THE EAST AND SOUTH. DEFINITE
DRYING TREND NC/NW ZONES. FOR WED AND BEYOND...ANOTHER DEEP TROUGH
INDICATED INTO THE WEST COAST LATE NEXT WEEK BUT MUCH UNCERTAINTY
ON HOW QUICKLY IT WILL PROGRESS EAST. FARTHER DOWNSTREAM OVER OUR
REGION... POSITIVELY TILTED UPPER RIDGE MOST LIKELY TO DOMINATE
WITH A DEFORMATION AXIS OF SOME SORTS STRETCHING FROM THE CENTRAL
PLAINS STATES INTO FAR EASTERN NM BUT LOW CONFIDENCE. LOW GRADE
POP FORECAST IN PLACE FOR NOW WITH TEMPS GENERALLY BELOW NORMAL
EAST...AND NEAR TO SLIGHTLY ABOVE WEST. KJ
&&
.FIRE WEATHER...
UPPER LOW NEAR THE CENTRAL TO S CALIFORNIA COAST TO BE AN IMPORTANT
DRIVER IN LOWERING SFC PRESSURE OVER OR JUST W OF W NM WHICH WILL
SHIFT WINDS TO SOMEWHAT OF AN EASTERLY COMPONENT ACROSS MOST OF THE
EAST TWO THIRDS OR THREE QUARTERS OF NM BY LATE AM TO EARLY PM
TODAY. SOME DRYING THANKS TO A MODERATE MID LEVEL DRY INTRUSION
EXPECTED MAINLY ACROSS WESTERN AREAS. THE BEST CHANCE OF WETTING
RAIN TO BE FOUND ACROSS THE SE AND ALSO MUCH OF THE HIGHER TERRAIN
ELSEWHERE. GAP WIND GUSTS RANGING FROM 30 TO 40 MPH WILL BE EXPECTED
ALONG THE RIO GRANDE VALLEY TONIGHT INTO SUN MORNING. RESIDUAL SFC
MOISTURE AND MID TO UPPER LVL FLOW SHIFTING FROM E AND NE TODAY TO
MORE OF A SE TO S FLOW SUN TO SUN NIGHT PERIOD. THIS SHOULD HELP
ENHANCE WETTING RAIN POTENTIAL FOR SUN...FAVORING MOST THE CENTRAL
MTN CHAIN AND EAST AS WELL AS AREAS NEAR TO WEST OF THE DIVIDE.
AFTN TEMPS SHOULD BE WILL COOL ROUGHLY 5 TO 10 DEGREES MOST SPOTS
EXCEPT PERHAPS A BIT LESS SO ACROSS FAR E NM...BUT REMAIN NEAR
NORMAL ACROSS ROUGHLY THE NE HALF OF THE STATE. SOME BREEZY LEVEL
WIND AREAS EMBEDDED IN THE GENERALLY S TO SE FLOW SUN. VENTILATION
RATES LOOK TO BE FAIR TO GOOD FOR AREAS NORTH OF THE INTERSTATE 40
CORRIDOR.
MON TO AGAIN SOME WETTING RAIN CHANCES AND BELOW NORMAL TEMPERATURES
IN THE EAST AND TO SOME DEGREE SOUTH...LESS WETTING RAIN POTENTIAL
WITH NEAR NORMAL TEMPERATURES TO THE NW. VENTILATION NOT EXPECTED TO
CHANGE A LOT BETWEEN SUNDAY TO MONDAY WITH BETTER READINGS GENERALLY
ALONG AND NORTH OF I40.
A DRYING TREND STILL APPEARS TO BE IN THE CARDS OVER THE AREA
STARTING TUE INTO AT LEAST THU...THOUGH A WEAK FRONTAL BOUNDARY IS
STILL ANTICIPATED MID WEEK AND FAVOR THE EAST SLOPES OF THE CENTRAL
MTNS EASTWARD. VENTILATION IS EXPECTED TO LOWER SOME, THOUGH NOT
DRASTICALLY...TUE AND WED. THE NEXT UPPER TROUGH STILL LOOKS TO
APPROACH FOR LATE WEEK INTO THE FOLLOWING WEEKEND. SOME FCST MODEL
DIFFERENCES REMAIN IN STRENGTH AND TIMING. GFS MODEL STILL LOOKS
DEEPER AND SOMEWHAT FASTER WITH THE TROUGH THUS SOME WIND IMPACTS
POSSIBLE AHEAD OF IT. THIS SHOULD IMPROVE VENTILATION RATES. ECMWF
STILL IS A BIT SLOWER. MODEL DIFFERENCES STILL DRIVING DOWN
CONFIDENCE SOME FOR LATE WEEK INTO NEXT WEEK. 43
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1148 AM MDT SAT SEP 20 2014
.AVIATION...
18Z TAF CYCLE
STILL SOME IFR CIGS PERSISTING ROUGHLY SE OF A LINE FROM KSRR TO
KTCC. KROW WILL BE IMPACTED THE MOST...THOUGH SHOULD SEE IT WAFFLE
BTW SCT AND BKN OVER THE NEXT FEW HOURS. EASTERLY WINDS WILL
INCREASE AS THE AFTN PROGRESSES...ESPECIALLY BELOW GAPS AT KABQ
AND KSAF. MAY NEED TO ISSUE AN AWW LATER FOR KABQ FOR WIND GUSTS
GREATER THAN 35KT. OTHERWISE...SOME SPOTTY SHRA AND TSRA ACROSS
THE NORTH AND WEST THIS AFTN/EVE. CONFIDENCE IS ONLY HIGH ENOUGH
TO INCLUDE A VC MENTION AT THIS TIME AT KFMN...KGUP AND KSAF.
SHOULD SEE ANOTHER ROUND OF LIFR/IFR CIGS AND PERHAPS VSBYS AFT
06Z TONIGHT ALONG AND EAST OF THE CENTRAL MT CHAIN. MAY ALSO SEE
A FEW SHOWERS DEVELOP AROUND KROW NEAR SUNRISE SUNDAY.
34
&&
.PREV DISCUSSION...348 AM MDT SAT SEP 20 2014...
.SYNOPSIS...
VERY MOIST AIR MASS TO REMAIN IN PLACE ACROSS SOUTHEAST NEW MEXICO
WHERE SHOWERS AND A FEW THUNDERSTORMS ARE MOST FAVORED. DEEPER
MOISTURE WILL EXPAND WESTWARD LATE TODAY AND TONIGHT...WITH SHOWER
AND THUNDERSTORM ACTIVITY EXPECTED TO INCREASE AGAIN FOR PARTS OF
THE EASTERN PLAINS. AN OVERALL UPTICK IN SHOWER AND THUNDERSTORM
ACTIVITY IS EXPECTED FOR SUNDAY AND SUNDAY EVENING AS A
DISTURBANCE ALOFT PASSES JUST NORTH OF THE STATE AND HELPS TO DRAW
MOISTURE FARTHER NORTH AND WEST. DRIER AIR WILL THEN SPREAD
EASTWARD INTO NORTHWEST NEW MEXICO MONDAY AND MOST AREAS TUESDAY.
MEANWHILE... TEMPERATURES WILL REMAIN GENERALLY ABOVE NORMAL
ACROSS THE WEST AND BELOW NORMAL ACROSS THE EAST. BY THE MIDDLE OF
NEXT WEEK...A DRYING TREND WILL TAKE A STRONGER HOLD ON THE
AREA...AND TEMPERATURES WILL BE NEAR TO SLIGHTLY ABOVE NORMAL
EXCEPT FOR THE SOUTHEAST PLAINS WHERE COOLER THAN AVERAGE
TEMPERATURE WILL LIKELY LINGER.
&&
.DISCUSSION...
EXTENSIVE LOW CLOUDS AND AT LEAST PATCHY DENSE FOG EAST OF THE
CENTRAL MOUNTAIN CHAIN EARLY THIS MORNING. EXPECT FOG TO
DEVELOP/EXPAND AND HAVE GREATEST IMPACT ALONG THE IMMEDIATE EAST
SLOPES AND ALONG THE WESTERN FRINGES OF PERSISTENT STRATUS DECK.
VERY MOIST AIR MASS REMAINS IN PLACE ACROSS THE SOUTHEAST PLAINS
WHERE SURFACE DEW POINT TEMPS SOLIDLY IN THE MID/UPPER 60S. THUS
EVEN WEAK UPSLOPE/LOW LEVEL CONVERGENCE IN THIS ENVIRON ENOUGH TO
GENERATE ISOLATED ACTIVITY THIS MORNING...AND ALL INDICATIONS
POINT TOWARD A GRADUAL STRENGTHENING OF THE E-SE BOUNDARY LAYER
WINDS ACROSS THE PLAINS AS THE DAY PROGRESSES AND MORESO INTO THE
EVENING HOURS. LATEST 13KM RAPID REFRESH /RAP/ AND HRRR MODEL RUNS
CONTINUE TO SUPPORT ISO-SCT COVERAGE FOR THE EC/SE ZONES TODAY.
AND GOOD AGREEMENT BETWEEN GFS/NAM SUPPORTING PREVIOUS POP/WX
TRENDS INCREASING POP FOR SE 1/4 TONIGHT WITH A PREFERRED AXIS
ALONG/WEST OF THE PECOS RIVER VALLEY TO EAST SLOPES OF THE SC
MOUNTAINS WHERE UPSLOPE EFFECTS WILL BE MAXIMIZED.
OUTSIDE THE SC MTNS AND EC/SE PLAINS...A PREDOMINATELY DRY AND
UNSEASONABLY WARM FORECAST TODAY BENEATH GRADUALLY STRENGTHENING
HIGH PRESSURE ALOFT THAT SHOULD CENTER NEAR OR JUST NORTH OF THE
NM/CO LINE TODAY BEFORE DEFLATING AND SHIFTING EAST AND SOUTH
TONIGHT- SUNDAY. THE SLIGHT AMPLIFICATION OF THE RIDGE ALOFT TODAY
AND THEN TRENDS INTO SUNDAY DUE TO A CLOSED LOW FORECAST TO MOVE
INTO CENTRAL CA LATE TODAY- TONIGHT THEN ACROSS THE GREAT BASIN
SUNDAY. THE ONE EXCEPTION TO THE PREDOMINATELY DRY FORECAST TODAY
WILL BE CATRON COUNTY/UPPER GILA REGION EXTENDING NORTH TOWARD THE
ZUNI MOUNTAINS NEAR THE NM/AZ LINE WHERE MID LEVEL MOISTURE
EXPECTED TO ADVECT NORTHWARD IN THE DEVELOPING S-SELY FLOW. AN
EXPANSION OF ISOLATED TO SCATTERED POPS EXPECTED AREAWIDE BY
SUNDAY...ESPECIALLY THE NORTH AND WEST...AS FORCING FOR LARGE-
SCALE LIFT AIDS CONVECTION SUNDAY PM. SURFACE PRESSURE FALLS TO
THE WEST OF THE STATE ASSOCIATED WITH THE CA LOW PRESSURE SYSTEM
MOST LIKELY RESPONSIBLE FOR THE STRENGTHENING E-SELY BOUNDARY
LAYER LATE TODAY AND TONIGHT. THIS WILL BRING HIGHER DEW POINT AIR
WESTWARD CONTRIBUTING TO THE OVERALL IMPROVING SHRA/TSRA CHANCES.
STORM MOTIONS WILL BE FAIRLY FAST BUT COULD SEE A FEW STRONG CELLS
DEVELOP SUNDAY PM NW ZONES.
CLOSED LOW TO OPEN UP AND PASS NORTH OF THE STATE MONDAY...WITH
PROGRESSIVELY DRIER AIR MASS INTO THE FOUR CORNERS. BEST POPS FROM
NE TO SW. TRANSITION TO NWLY FLOW ALOFT ON TUESDAY THAT WOULD
FAVOR THE NC/NE AREAS BUT WITH RESIDUAL MOISTURE CANNOT RULE OUT
ISOLATED- SCATTERED SHRA/TSRA ACROSS THE EAST AND SOUTH. DEFINITE
DRYING TREND NC/NW ZONES. FOR WED AND BEYOND...ANOTHER DEEP TROUGH
INDICATED INTO THE WEST COAST LATE NEXT WEEK BUT MUCH UNCERTAINTY
ON HOW QUICKLY IT WILL PROGRESS EAST. FARTHER DOWNSTREAM OVER OUR
REGION... POSITIVELY TILTED UPPER RIDGE MOST LIKELY TO DOMINATE
WITH A DEFORMATION AXIS OF SOME SORTS STRETCHING FROM THE CENTRAL
PLAINS STATES INTO FAR EASTERN NM BUT LOW CONFIDENCE. LOW GRADE
POP FORECAST IN PLACE FOR NOW WITH TEMPS GENERALLY BELOW NORMAL
EAST...AND NEAR TO SLIGHTLY ABOVE WEST. KJ
&&
.FIRE WEATHER...
UPPER LOW NEAR THE CENTRAL TO S CALIFORNIA COAST TO BE AN IMPORTANT
DRIVER IN LOWERING SFC PRESSURE OVER OR JUST W OF W NM WHICH WILL
SHIFT WINDS TO SOMEWHAT OF AN EASTERLY COMPONENT ACROSS MOST OF THE
EAST TWO THIRDS OR THREE QUARTERS OF NM BY LATE AM TO EARLY PM
TODAY. SOME DRYING THANKS TO A MODERATE MID LEVEL DRY INTRUSION
EXPECTED MAINLY ACROSS WESTERN AREAS. THE BEST CHANCE OF WETTING
RAIN TO BE FOUND ACROSS THE SE AND ALSO MUCH OF THE HIGHER TERRAIN
ELSEWHERE. GAP WIND GUSTS RANGING FROM 30 TO 40 MPH WILL BE EXPECTED
ALONG THE RIO GRANDE VALLEY TONIGHT INTO SUN MORNING. RESIDUAL SFC
MOISTURE AND MID TO UPPER LVL FLOW SHIFTING FROM E AND NE TODAY TO
MORE OF A SE TO S FLOW SUN TO SUN NIGHT PERIOD. THIS SHOULD HELP
ENHANCE WETTING RAIN POTENTIAL FOR SUN...FAVORING MOST THE CENTRAL
MTN CHAIN AND EAST AS WELL AS AREAS NEAR TO WEST OF THE DIVIDE.
AFTN TEMPS SHOULD BE WILL COOL ROUGHLY 5 TO 10 DEGREES MOST SPOTS
EXCEPT PERHAPS A BIT LESS SO ACROSS FAR E NM...BUT REMAIN NEAR
NORMAL ACROSS ROUGHLY THE NE HALF OF THE STATE. SOME BREEZY LEVEL
WIND AREAS EMBEDDED IN THE GENERALLY S TO SE FLOW SUN. VENTILATION
RATES LOOK TO BE FAIR TO GOOD FOR AREAS NORTH OF THE INTERSTATE 40
CORRIDOR.
MON TO AGAIN SOME WETTING RAIN CHANCES AND BELOW NORMAL TEMPERATURES
IN THE EAST AND TO SOME DEGREE SOUTH...LESS WETTING RAIN POTENTIAL
WITH NEAR NORMAL TEMPERATURES TO THE NW. VENTILATION NOT EXPECTED TO
CHANGE A LOT BETWEEN SUNDAY TO MONDAY WITH BETTER READINGS GENERALLY
ALONG AND NORTH OF I40.
A DRYING TREND STILL APPEARS TO BE IN THE CARDS OVER THE AREA
STARTING TUE INTO AT LEAST THU...THOUGH A WEAK FRONTAL BOUNDARY IS
STILL ANTICIPATED MID WEEK AND FAVOR THE EAST SLOPES OF THE CENTRAL
MTNS EASTWARD. VENTILATION IS EXPECTED TO LOWER SOME, THOUGH NOT
DRASTICALLY...TUE AND WED. THE NEXT UPPER TROUGH STILL LOOKS TO
APPROACH FOR LATE WEEK INTO THE FOLLOWING WEEKEND. SOME FCST MODEL
DIFFERENCES REMAIN IN STRENGTH AND TIMING. GFS MODEL STILL LOOKS
DEEPER AND SOMEWHAT FASTER WITH THE TROUGH THUS SOME WIND IMPACTS
POSSIBLE AHEAD OF IT. THIS SHOULD IMPROVE VENTILATION RATES. ECMWF
STILL IS A BIT SLOWER. MODEL DIFFERENCES STILL DRIVING DOWN
CONFIDENCE SOME FOR LATE WEEK INTO NEXT WEEK. 43
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
616 AM MDT SAT SEP 20 2014
.AVIATION...
12Z TAF CYCLE
WIDESPREAD IFR AND SPOTTY LIFR CIGS AND VSBY ACROSS GOOD PORTION
OF SE PLAINS WEST AND THEN NORTH ACROSS THE EAST SLOPES OF CENTRAL
MT CHAIN AND IMMEDIATELY ADJACENT HIGHLANDS TO THE EAST TIL AT
LEAST 15Z OR 16Z BEFORE SOME RISE OR BREAKS IN CIGS SETS IN.
EXPECT MT OBSCURATIONS AS WELL. ELSEWHERE IN EAST NM CIGS ARE A
LITTLE LESS WIDESPREAD AND GENERALLY MVFR WITH SOME SPOTTY IFR
MIXED IN. THIS ALSO TO IMPROVE MID TO LATE MORN. MOSTLY VFR
CONDITIONS TO WEST OF CENTRAL MT CHAIN. NEAR SFC WIND FLOW TO
TURN TO MORE OF AN EASTERLY COMPONENT AS THE DAY PROGRESSES TODAY.
BELOW CANYONS AND PASSES OF CENTRAL MT CHAIN E TO SE WIND GUSTS
WILL DEVELOP BETWEEN 21 AND 00Z. MAINLY FROM NEAR 00Z AND ABOUT
09Z OR A BIT LATER WIND GUSTS TO REACH BETWEEN 28 AND 35 KTS BELOW
CANYONS...INCLUDING ABQ AND SAF WITH SUSTAINED SPEEDS BETWEEN 15
AND 26 KT. SOME SPOTTY SHRA/TSRA TO REDEVELOP MAINLY SOUTHERN AND
WESTERN AREAS NEAR AND ESPECIALLY AFTER 20Z...FAVORING HIGHER
TERRAIN AT FIRST...MORE ISOLATED ACTIVITY ACROSS NORTHERN MTS.
SOME ACTIVITY TO CONTINUE OVERNIGHT TONIGHT. ALSO SOME MVFR AND
IFR CIGS AGAIN FAIRLY LIKELY LATER TONIGHT ALONG EAST SLOPES
CENTRAL MT CHAIN AS WELL AS SE AND PERHAPS E CENTRAL PLAINS.
43
&&
.PREV DISCUSSION...348 AM MDT SAT SEP 20 2014...
.SYNOPSIS...
VERY MOIST AIR MASS TO REMAIN IN PLACE ACROSS SOUTHEAST NEW MEXICO
WHERE SHOWERS AND A FEW THUNDERSTORMS ARE MOST FAVORED. DEEPER MOISTURE
WILL EXPAND WESTWARD LATE TODAY AND TONIGHT...WITH SHOWER AND
THUNDERSTORM ACTIVITY EXPECTED TO INCREASE AGAIN FOR PARTS OF THE
EASTERN PLAINS. AN OVERALL UPTICK IN SHOWER AND THUNDERSTORM
ACTIVITY IS EXPECTED FOR SUNDAY AND SUNDAY EVENING AS A DISTURBANCE
ALOFT PASSES JUST NORTH OF THE STATE AND HELPS TO DRAW MOISTURE
FARTHER NORTH AND WEST. DRIER AIR WILL THEN SPREAD EASTWARD INTO NORTHWEST
NEW MEXICO MONDAY AND MOST AREAS TUESDAY. MEANWHILE... TEMPERATURES
WILL REMAIN GENERALLY ABOVE NORMAL ACROSS THE WEST AND BELOW
NORMAL ACROSS THE EAST. BY THE MIDDLE OF NEXT WEEK...A DRYING
TREND WILL TAKE A STRONGER HOLD ON THE AREA...AND TEMPERATURES
WILL BE NEAR TO SLIGHTLY ABOVE NORMAL EXCEPT FOR THE SOUTHEAST
PLAINS WHERE COOLER THAN AVERAGE TEMPERATURE WILL LIKELY LINGER.
&&
.DISCUSSION...
EXTENSIVE LOW CLOUDS AND AT LEAST PATCHY DENSE FOG EAST OF THE
CENTRAL MOUNTAIN CHAIN EARLY THIS MORNING. EXPECT FOG TO
DEVELOP/EXPAND AND HAVE GREATEST IMPACT ALONG THE IMMEDIATE EAST
SLOPES AND ALONG THE WESTERN FRINGES OF PERSISTENT STRATUS DECK.
VERY MOIST AIR MASS REMAINS IN PLACE ACROSS THE SOUTHEAST PLAINS
WHERE SURFACE DEW POINT TEMPS SOLIDLY IN THE MID/UPPER 60S. THUS
EVEN WEAK UPSLOPE/LOW LEVEL CONVERGENCE IN THIS ENVIRON ENOUGH TO
GENERATE ISOLATED ACTIVITY THIS MORNING...AND ALL INDICATIONS
POINT TOWARD A GRADUAL STRENGTHENING OF THE E-SE BOUNDARY LAYER
WINDS ACROSS THE PLAINS AS THE DAY PROGRESSES AND MORESO INTO THE
EVENING HOURS. LATEST 13KM RAPID REFRESH /RAP/ AND HRRR MODEL RUNS
CONTINUE TO SUPPORT ISO-SCT COVERAGE FOR THE EC/SE ZONES TODAY.
AND GOOD AGREEMENT BETWEEN GFS/NAM SUPPORTING PREVIOUS POP/WX
TRENDS INCREASING POP FOR SE 1/4 TONIGHT WITH A PREFERRED AXIS
ALONG/WEST OF THE PECOS RIVER VALLEY TO EAST SLOPES OF THE SC
MOUNTAINS WHERE UPSLOPE EFFECTS WILL BE MAXIMIZED.
OUTSIDE THE SC MTNS AND EC/SE PLAINS...A PREDOMINATELY DRY AND
UNSEASONABLY WARM FORECAST TODAY BENEATH GRADUALLY STRENGTHENING
HIGH PRESSURE ALOFT THAT SHOULD CENTER NEAR OR JUST NORTH OF THE
NM/CO LINE TODAY BEFORE DEFLATING AND SHIFTING EAST AND SOUTH
TONIGHT- SUNDAY. THE SLIGHT AMPLIFICATION OF THE RIDGE ALOFT TODAY
AND THEN TRENDS INTO SUNDAY DUE TO A CLOSED LOW FORECAST TO MOVE
INTO CENTRAL CA LATE TODAY- TONIGHT THEN ACROSS THE GREAT BASIN
SUNDAY. THE ONE EXCEPTION TO THE PREDOMINATELY DRY FORECAST TODAY
WILL BE CATRON COUNTY/UPPER GILA REGION EXTENDING NORTH TOWARD THE
ZUNI MOUNTAINS NEAR THE NM/AZ LINE WHERE MID LEVEL MOISTURE
EXPECTED TO ADVECT NORTHWARD IN THE DEVELOPING S-SELY FLOW. AN
EXPANSION OF ISOLATED TO SCATTERED POPS EXPECTED AREAWIDE BY
SUNDAY...ESPECIALLY THE NORTH AND WEST...AS FORCING FOR LARGE-
SCALE LIFT AIDS CONVECTION SUNDAY PM. SURFACE PRESSURE FALLS TO
THE WEST OF THE STATE ASSOCIATED WITH THE CA LOW PRESSURE SYSTEM
MOST LIKELY RESPONSIBLE FOR THE STRENGTHENING E-SELY BOUNDARY
LAYER LATE TODAY AND TONIGHT. THIS WILL BRING HIGHER DEW POINT AIR
WESTWARD CONTRIBUTING TO THE OVERALL IMPROVING SHRA/TSRA CHANCES.
STORM MOTIONS WILL BE FAIRLY FAST BUT COULD SEE A FEW STRONG CELLS
DEVELOP SUNDAY PM NW ZONES.
CLOSED LOW TO OPEN UP AND PASS NORTH OF THE STATE MONDAY...WITH
PROGRESSIVELY DRIER AIR MASS INTO THE FOUR CORNERS. BEST POPS FROM
NE TO SW. TRANSITION TO NWLY FLOW ALOFT ON TUESDAY THAT WOULD
FAVOR THE NC/NE AREAS BUT WITH RESIDUAL MOISTURE CANNOT RULE OUT
ISOLATED- SCATTERED SHRA/TSRA ACROSS THE EAST AND SOUTH. DEFINITE
DRYING TREND NC/NW ZONES. FOR WED AND BEYOND...ANOTHER DEEP TROUGH
INDICATED INTO THE WEST COAST LATE NEXT WEEK BUT MUCH UNCERTAINTY
ON HOW QUICKLY IT WILL PROGRESS EAST. FARTHER DOWNSTREAM OVER OUR
REGION... POSITIVELY TILTED UPPER RIDGE MOST LIKELY TO DOMINATE
WITH A DEFORMATION AXIS OF SOME SORTS STRETCHING FROM THE CENTRAL
PLAINS STATES INTO FAR EASTERN NM BUT LOW CONFIDENCE. LOW GRADE
POP FORECAST IN PLACE FOR NOW WITH TEMPS GENERALLY BELOW NORMAL
EAST...AND NEAR TO SLIGHTLY ABOVE WEST. KJ
&&
.FIRE WEATHER...
UPPER LOW NEAR THE CENTRAL TO S CALIFORNIA COAST TO BE AN IMPORTANT
DRIVER IN LOWERING SFC PRESSURE OVER OR JUST W OF W NM WHICH WILL
SHIFT WINDS TO SOMEWHAT OF AN EASTERLY COMPONENT ACROSS MOST OF THE
EAST TWO THIRDS OR THREE QUARTERS OF NM BY LATE AM TO EARLY PM
TODAY. SOME DRYING THANKS TO A MODERATE MID LEVEL DRY INTRUSION
EXPECTED MAINLY ACROSS WESTERN AREAS. THE BEST CHANCE OF WETTING
RAIN TO BE FOUND ACROSS THE SE AND ALSO MUCH OF THE HIGHER TERRAIN
ELSEWHERE. GAP WIND GUSTS RANGING FROM 30 TO 40 MPH WILL BE EXPECTED
ALONG THE RIO GRANDE VALLEY TONIGHT INTO SUN MORNING. RESIDUAL SFC
MOISTURE AND MID TO UPPER LVL FLOW SHIFTING FROM E AND NE TODAY TO
MORE OF A SE TO S FLOW SUN TO SUN NIGHT PERIOD. THIS SHOULD HELP
ENHANCE WETTING RAIN POTENTIAL FOR SUN...FAVORING MOST THE CENTRAL
MTN CHAIN AND EAST AS WELL AS AREAS NEAR TO WEST OF THE DIVIDE.
AFTN TEMPS SHOULD BE WILL COOL ROUGHLY 5 TO 10 DEGREES MOST SPOTS
EXCEPT PERHAPS A BIT LESS SO ACROSS FAR E NM...BUT REMAIN NEAR
NORMAL ACROSS ROUGHLY THE NE HALF OF THE STATE. SOME BREEZY LEVEL
WIND AREAS EMBEDDED IN THE GENERALLY S TO SE FLOW SUN. VENTILATION
RATES LOOK TO BE FAIR TO GOOD FOR AREAS NORTH OF THE INTERSTATE 40
CORRIDOR.
MON TO AGAIN SOME WETTING RAIN CHANCES AND BELOW NORMAL TEMPERATURES
IN THE EAST AND TO SOME DEGREE SOUTH...LESS WETTING RAIN POTENTIAL
WITH NEAR NORMAL TEMPERATURES TO THE NW. VENTILATION NOT EXPECTED TO
CHANGE A LOT BETWEEN SUNDAY TO MONDAY WITH BETTER READINGS GENERALLY
ALONG AND NORTH OF I40.
A DRYING TREND STILL APPEARS TO BE IN THE CARDS OVER THE AREA
STARTING TUE INTO AT LEAST THU...THOUGH A WEAK FRONTAL BOUNDARY IS
STILL ANTICIPATED MID WEEK AND FAVOR THE EAST SLOPES OF THE CENTRAL
MTNS EASTWARD. VENTILATION IS EXPECTED TO LOWER SOME, THOUGH NOT
DRASTICALLY...TUE AND WED. THE NEXT UPPER TROUGH STILL LOOKS TO
APPROACH FOR LATE WEEK INTO THE FOLLOWING WEEKEND. SOME FCST MODEL
DIFFERENCES REMAIN IN STRENGTH AND TIMING. GFS MODEL STILL LOOKS
DEEPER AND SOMEWHAT FASTER WITH THE TROUGH THUS SOME WIND IMPACTS
POSSIBLE AHEAD OF IT. THIS SHOULD IMPROVE VENTILATION RATES. ECMWF
STILL IS A BIT SLOWER. MODEL DIFFERENCES STILL DRIVING DOWN
CONFIDENCE SOME FOR LATE WEEK INTO NEXT WEEK. 43
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
348 AM MDT SAT SEP 20 2014
.SYNOPSIS...
VERY MOIST AIR MASS TO REMAIN IN PLACE ACROSS SOUTHEAST NEW MEXICO
WHERE SHOWERS AND A FEW THUNDERSTORMS ARE MOST FAVORED. DEEPER MOISTURE
WILL EXPAND WESTWARD LATE TODAY AND TONIGHT...WITH SHOWER AND
THUNDERSTORM ACTIVITY EXPECTED TO INCREASE AGAIN FOR PARTS OF THE
EASTERN PLAINS. AN OVERALL UPTICK IN SHOWER AND THUNDERSTORM
ACTIVITY IS EXPECTED FOR SUNDAY AND SUNDAY EVENING AS A DISTURBANCE
ALOFT PASSES JUST NORTH OF THE STATE AND HELPS TO DRAW MOISTURE
FARTHER NORTH AND WEST. DRIER AIR WILL THEN SPREAD EASTWARD INTO NORTHWEST
NEW MEXICO MONDAY AND MOST AREAS TUESDAY. MEANWHILE... TEMPERATURES
WILL REMAIN GENERALLY ABOVE NORMAL ACROSS THE WEST AND BELOW
NORMAL ACROSS THE EAST. BY THE MIDDLE OF NEXT WEEK...A DRYING
TREND WILL TAKE A STRONGER HOLD ON THE AREA...AND TEMPERATURES
WILL BE NEAR TO SLIGHTLY ABOVE NORMAL EXCEPT FOR THE SOUTHEAST
PLAINS WHERE COOLER THAN AVERAGE TEMPERATURE WILL LIKELY LINGER.
&&
.DISCUSSION...
EXTENSIVE LOW CLOUDS AND AT LEAST PATCHY DENSE FOG EAST OF THE
CENTRAL MOUNTAIN CHAIN EARLY THIS MORNING. EXPECT FOG TO
DEVELOP/EXPAND AND HAVE GREATEST IMPACT ALONG THE IMMEDIATE EAST
SLOPES AND ALONG THE WESTERN FRINGES OF PERSISTENT STRATUS DECK.
VERY MOIST AIR MASS REMAINS IN PLACE ACROSS THE SOUTHEAST PLAINS
WHERE SURFACE DEW POINT TEMPS SOLIDLY IN THE MID/UPPER 60S. THUS
EVEN WEAK UPSLOPE/LOW LEVEL CONVERGENCE IN THIS ENVIRON ENOUGH TO
GENERATE ISOLATED ACTIVITY THIS MORNING...AND ALL INDICATIONS
POINT TOWARD A GRADUAL STRENGTHENING OF THE E-SE BOUNDARY LAYER
WINDS ACROSS THE PLAINS AS THE DAY PROGRESSES AND MORESO INTO THE
EVENING HOURS. LATEST 13KM RAPID REFRESH /RAP/ AND HRRR MODEL RUNS
CONTINUE TO SUPPORT ISO-SCT COVERAGE FOR THE EC/SE ZONES TODAY.
AND GOOD AGREEMENT BETWEEN GFS/NAM SUPPORTING PREVIOUS POP/WX
TRENDS INCREASING POP FOR SE 1/4 TONIGHT WITH A PREFERRED AXIS
ALONG/WEST OF THE PECOS RIVER VALLEY TO EAST SLOPES OF THE SC
MOUNTAINS WHERE UPSLOPE EFFECTS WILL BE MAXIMIZED.
OUTSIDE THE SC MTNS AND EC/SE PLAINS...A PREDOMINATELY DRY AND
UNSEASONABLY WARM FORECAST TODAY BENEATH GRADUALLY STRENGTHENING
HIGH PRESSURE ALOFT THAT SHOULD CENTER NEAR OR JUST NORTH OF THE
NM/CO LINE TODAY BEFORE DEFLATING AND SHIFTING EAST AND SOUTH
TONIGHT- SUNDAY. THE SLIGHT AMPLIFICATION OF THE RIDGE ALOFT TODAY
AND THEN TRENDS INTO SUNDAY DUE TO A CLOSED LOW FORECAST TO MOVE
INTO CENTRAL CA LATE TODAY- TONIGHT THEN ACROSS THE GREAT BASIN
SUNDAY. THE ONE EXCEPTION TO THE PREDOMINATELY DRY FORECAST TODAY
WILL BE CATRON COUNTY/UPPER GILA REGION EXTENDING NORTH TOWARD THE
ZUNI MOUNTAINS NEAR THE NM/AZ LINE WHERE MID LEVEL MOISTURE
EXPECTED TO ADVECT NORTHWARD IN THE DEVELOPING S-SELY FLOW. AN
EXPANSION OF ISOLATED TO SCATTERED POPS EXPECTED AREAWIDE BY
SUNDAY...ESPECIALLY THE NORTH AND WEST...AS FORCING FOR LARGE-
SCALE LIFT AIDS CONVECTION SUNDAY PM. SURFACE PRESSURE FALLS TO
THE WEST OF THE STATE ASSOCIATED WITH THE CA LOW PRESSURE SYSTEM
MOST LIKELY RESPONSIBLE FOR THE STRENGTHENING E-SELY BOUNDARY
LAYER LATE TODAY AND TONIGHT. THIS WILL BRING HIGHER DEW POINT AIR
WESTWARD CONTRIBUTING TO THE OVERALL IMPROVING SHRA/TSRA CHANCES.
STORM MOTIONS WILL BE FAIRLY FAST BUT COULD SEE A FEW STRONG CELLS
DEVELOP SUNDAY PM NW ZONES.
CLOSED LOW TO OPEN UP AND PASS NORTH OF THE STATE MONDAY...WITH
PROGRESSIVELY DRIER AIR MASS INTO THE FOUR CORNERS. BEST POPS FROM
NE TO SW. TRANSITION TO NWLY FLOW ALOFT ON TUESDAY THAT WOULD
FAVOR THE NC/NE AREAS BUT WITH RESIDUAL MOISTURE CANNOT RULE OUT
ISOLATED- SCATTERED SHRA/TSRA ACROSS THE EAST AND SOUTH. DEFINITE
DRYING TREND NC/NW ZONES. FOR WED AND BEYOND...ANOTHER DEEP TROUGH
INDICATED INTO THE WEST COAST LATE NEXT WEEK BUT MUCH UNCERTAINTY
ON HOW QUICKLY IT WILL PROGRESS EAST. FARTHER DOWNSTREAM OVER OUR
REGION... POSITIVELY TILTED UPPER RIDGE MOST LIKELY TO DOMINATE
WITH A DEFORMATION AXIS OF SOME SORTS STRETCHING FROM THE CENTRAL
PLAINS STATES INTO FAR EASTERN NM BUT LOW CONFIDENCE. LOW GRADE
POP FORECAST IN PLACE FOR NOW WITH TEMPS GENERALLY BELOW NORMAL
EAST...AND NEAR TO SLIGHTLY ABOVE WEST. KJ
&&
.FIRE WEATHER...
UPPER LOW NEAR THE CENTRAL TO S CALIFORNIA COAST TO BE AN IMPORTANT
DRIVER IN LOWERING SFC PRESSURE OVER OR JUST W OF W NM WHICH WILL
SHIFT WINDS TO SOMEWHAT OF AN EASTERLY COMPONENT ACROSS MOST OF THE
EAST TWO THIRDS OR THREE QUARTERS OF NM BY LATE AM TO EARLY PM
TODAY. SOME DRYING THANKS TO A MODERATE MID LEVEL DRY INTRUSION
EXPECTED MAINLY ACROSS WESTERN AREAS. THE BEST CHANCE OF WETTING
RAIN TO BE FOUND ACROSS THE SE AND ALSO MUCH OF THE HIGHER TERRAIN
ELSEWHERE. GAP WIND GUSTS RANGING FROM 30 TO 40 MPH WILL BE EXPECTED
ALONG THE RIO GRANDE VALLEY TONIGHT INTO SUN MORNING. RESIDUAL SFC
MOISTURE AND MID TO UPPER LVL FLOW SHIFTING FROM E AND NE TODAY TO
MORE OF A SE TO S FLOW SUN TO SUN NIGHT PERIOD. THIS SHOULD HELP
ENHANCE WETTING RAIN POTENTIAL FOR SUN...FAVORING MOST THE CENTRAL
MTN CHAIN AND EAST AS WELL AS AREAS NEAR TO WEST OF THE DIVIDE.
AFTN TEMPS SHOULD BE WILL COOL ROUGHLY 5 TO 10 DEGREES MOST SPOTS
EXCEPT PERHAPS A BIT LESS SO ACROSS FAR E NM...BUT REMAIN NEAR
NORMAL ACROSS ROUGHLY THE NE HALF OF THE STATE. SOME BREEZY LEVEL
WIND AREAS EMBEDDED IN THE GENERALLY S TO SE FLOW SUN. VENTILATION
RATES LOOK TO BE FAIR TO GOOD FOR AREAS NORTH OF THE INTERSTATE 40
CORRIDOR.
MON TO AGAIN SOME WETTING RAIN CHANCES AND BELOW NORMAL TEMPERATURES
IN THE EAST AND TO SOME DEGREE SOUTH...LESS WETTING RAIN POTENTIAL
WITH NEAR NORMAL TEMPERATURES TO THE NW. VENTILATION NOT EXPECTED TO
CHANGE A LOT BETWEEN SUNDAY TO MONDAY WITH BETTER READINGS GENERALLY
ALONG AND NORTH OF I40.
A DRYING TREND STILL APPEARS TO BE IN THE CARDS OVER THE AREA
STARTING TUE INTO AT LEAST THU...THOUGH A WEAK FRONTAL BOUNDARY IS
STILL ANTICIPATED MID WEEK AND FAVOR THE EAST SLOPES OF THE CENTRAL
MTNS EASTWARD. VENTILATION IS EXPECTED TO LOWER SOME, THOUGH NOT
DRASTICALLY...TUE AND WED. THE NEXT UPPER TROUGH STILL LOOKS TO
APPROACH FOR LATE WEEK INTO THE FOLLOWING WEEKEND. SOME FCST MODEL
DIFFERENCES REMAIN IN STRENGTH AND TIMING. GFS MODEL STILL LOOKS
DEEPER AND SOMEWHAT FASTER WITH THE TROUGH THUS SOME WIND IMPACTS
POSSIBLE AHEAD OF IT. THIS SHOULD IMPROVE VENTILATION RATES. ECMWF
STILL IS A BIT SLOWER. MODEL DIFFERENCES STILL DRIVING DOWN
CONFIDENCE SOME FOR LATE WEEK INTO NEXT WEEK. 43
&&
.AVIATION...
06Z TAF CYCLE
IFR CIGS WORKING INTO THE EASTERN PLAINS OVERNIGHT AND IN TAFS FOR
TCC...ROW...AND LVS. RIDGE BUILDING NORTHWARD ACROSS NM IN THE
WAKE OF ODILE...AS SURFACE LOW OVER NORTHERN MEXICO IMPARTS
EASTERLY COMPONENTS TO SURFACE WINDS THROUGH THE DAY ON SATURDAY.
GUSTS SQUIRTING THROUGH CENTRAL MT CHAIN GAPS OVER THE RIO GRANDE
VALLEY REFLECTED IN G30KT WINDS AT ABQ AND SAF FROM 01Z ONWARD SAT
EVENING. NEXT APPROACHING SYSTEM OVER CENTRAL CALIFORNIA WILL
SUPPORT SOME ISOLATED SHOWERS DRIFTING INTO WESTERN NEW MEXICO AND
IN TAFS FOR GUP AND FMN. OVERNIGHT MT OBSCURATION OVER THE
NORTHERN MTS AND ACROSS THE SOUTHERN TIER LATE SAT NIGHT.
SHY
&&
.PRELIMINARY POINT TEMPS/POPS...
FARMINGTON...................... 88 60 85 56 / 5 30 30 40
DULCE........................... 87 49 80 47 / 10 30 40 50
CUBA............................ 84 51 78 51 / 10 20 40 40
GALLUP.......................... 85 51 80 48 / 10 30 40 40
EL MORRO........................ 79 50 75 49 / 10 30 40 50
GRANTS.......................... 83 54 78 52 / 10 30 40 40
QUEMADO......................... 79 53 75 52 / 20 30 50 40
GLENWOOD........................ 83 52 82 54 / 30 30 30 30
CHAMA........................... 80 43 75 42 / 10 30 40 60
LOS ALAMOS...................... 81 57 74 55 / 10 20 40 40
PECOS........................... 77 53 69 52 / 10 30 50 50
CERRO/QUESTA.................... 78 48 75 48 / 10 20 40 40
RED RIVER....................... 71 44 66 44 / 10 30 50 50
ANGEL FIRE...................... 74 38 70 41 / 10 30 50 50
TAOS............................ 81 50 73 49 / 10 20 30 40
MORA............................ 77 50 68 50 / 10 30 50 50
ESPANOLA........................ 86 55 79 55 / 10 20 30 30
SANTA FE........................ 80 55 74 55 / 10 20 40 40
SANTA FE AIRPORT................ 84 55 77 55 / 10 20 40 30
ALBUQUERQUE FOOTHILLS........... 84 61 78 61 / 10 20 40 30
ALBUQUERQUE HEIGHTS............. 85 63 80 62 / 10 20 30 30
ALBUQUERQUE VALLEY.............. 86 60 81 61 / 10 20 30 30
ALBUQUERQUE WEST MESA........... 87 61 82 61 / 10 20 30 30
LOS LUNAS....................... 86 58 81 58 / 10 20 30 30
RIO RANCHO...................... 89 61 83 61 / 10 20 30 30
SOCORRO......................... 86 62 83 62 / 10 30 40 40
SANDIA PARK/CEDAR CREST......... 82 57 78 57 / 10 30 40 40
TIJERAS......................... 83 57 78 57 / 10 30 40 40
MORIARTY/ESTANCIA............... 81 49 74 50 / 10 30 50 40
CLINES CORNERS.................. 77 54 70 54 / 10 40 60 50
GRAN QUIVIRA.................... 78 57 71 57 / 20 40 50 40
CARRIZOZO....................... 81 60 74 60 / 20 40 50 30
RUIDOSO......................... 74 54 70 54 / 20 50 60 50
CAPULIN......................... 77 53 70 52 / 10 20 30 30
RATON........................... 82 52 76 52 / 10 20 40 30
SPRINGER........................ 83 53 74 54 / 10 30 40 30
LAS VEGAS....................... 78 52 71 52 / 10 40 60 50
CLAYTON......................... 82 59 77 57 / 10 20 30 30
ROY............................. 79 56 73 56 / 10 30 40 50
CONCHAS......................... 82 62 78 62 / 20 40 40 50
SANTA ROSA...................... 80 61 74 61 / 20 50 50 50
TUCUMCARI....................... 83 63 80 62 / 20 30 40 40
CLOVIS.......................... 77 62 76 61 / 40 40 50 50
PORTALES........................ 78 62 77 62 / 40 40 50 50
FORT SUMNER..................... 81 62 75 62 / 20 50 50 50
ROSWELL......................... 80 65 78 64 / 20 50 60 50
PICACHO......................... 77 59 71 60 / 20 50 60 50
ELK............................. 73 56 68 57 / 30 50 60 60
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
41
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1128 PM MDT FRI SEP 19 2014
.AVIATION...
06Z TAF CYCLE
IFR CIGS WORKING INTO THE EASTERN PLAINS OVERNIGHT AND IN TAFS FOR
TCC...ROW...AND LVS. RIDGE BUILDING NORTHWARD ACROSS NM IN THE
WAKE OF ODILE...AS SURFACE LOW OVER NORTHERN MEXICO IMPARTS
EASTERLY COMPONENTS TO SURFACE WINDS THROUGH THE DAY ON SATURDAY.
GUSTS SQUIRTING THROUGH CENTRAL MT CHAIN GAPS OVER THE RIO GRANDE
VALLEY REFLECTED IN G30KT WINDS AT ABQ AND SAF FROM 01Z ONWARD SAT
EVENING. NEXT APPROACHING SYSTEM OVER CENTRAL CALIFORNIA WILL
SUPPORT SOME ISOLATED SHOWERS DRIFTING INTO WESTERN NEW MEXICO AND
IN TAFS FOR GUP AND FMN. OVERNIGHT MT OBSCURATION OVER THE
NORTHERN MTS AND ACROSS THE SOUTHERN TIER LATE SAT NIGHT.
SHY
&&
.PREV DISCUSSION...743 PM MDT FRI SEP 19 2014...
.UPDATE...
UPDATED FORECAST TO LOWER PRECIPITATION CHANCES OVERNIGHT. MODELS CONTINUE
TO GENERATE LOTS OF QPF BUT SATELLITE AND RADAR IMAGERY INDICATING
NOT MUCH MORE THAN A FEW SHOWERS AND STORMS REMAIN OVER SERN NM.
INTERESTINGLY...A SMALL CLUSTER OF CONVECTION OVER THE SOUTHERN
SAN JUAN MOUNTAINS IN COLORADO CONTINUES TO DRIFT SWED TOWARD
THE CHAMA AREA. LEFT IN ISOLATED STORMS THROUGH THE EVENING
ALONG/NEAR THE COLORADO BORDER IN NORTH-CENTRAL NM AS A RESULT.
33
&&
.PREV DISCUSSION...308 PM MDT FRI SEP 19 2014...
.SYNOPSIS...
SHOWERS AND PERHAPS A THUNDERSTORM WILL CONTINUE THIS EVENING AND
OVERNIGHT ACROSS PORTIONS OF THE EASTERN PLAINS. THOUGH THE
DAYTIME HOURS ON SATURDAY SHOULD BE MOSTLY QUIET...AS MOISTURE
MOVES BACK INTO THE AREA FROM THE SOUTH AND EAST...SHOWER AND
THUNDERSTORM ACTIVITY IS EXPECTED TO RAMP BACK UP AGAIN SATURDAY
NIGHT AND SUNDAY. DRIER AIR WILL MOVE INTO THE STATE FROM WEST TO
EAST MONDAY AND TUESDAY. MEANWHILE...TEMPERATURES WILL REMAIN
GENERALLY ABOVE NORMAL ACROSS THE WEST AND BELOW NORMAL ACROSS THE
EAST. BY THE MIDDLE OF NEXT WEEK...STORM COVERAGE WILL BE
DWINDLING...AND TEMPERATURES WILL REBOUND WITHIN A FEW DEGREES OF
NORMAL AREA WIDE.
&&
.DISCUSSION...
RADAR AND OBSERVATIONS CONTINUE TO SHOW THAT MODELS ARE STRUGGLING
WITH QPF PLACEMENT AND AMOUNTS WITH THE REMNANTS OF ODILE. THIS IS
MAINLY BECAUSE ODILE CONTINUES TO STAY SOUTH OF PROJECTED TRACKS.
INTERESTINGLY...MOST OPERATIONAL MODELS CONTINUE TO SHOW QPF BULLS-
EYES OVER PORTIONS OF THE EASTERN PLAINS THRU THE OVERNIGHT...BUT
THE LATEST HRRR HAS TAKEN THE OPPOSITE TUNE...WITH ALMOST NO PRECIP
PREDICTED. EXPECT REALITY TO BE CLOSER TO THE DRIER
SCENARIO...THOUGH SOME SHOWERS SHOULD PERCOLATE OVERNIGHT ACROSS THE
PLAINS...MUCH LIKE WHAT IS OCCURRING NOW. HAVE ALSO LEFT IN ISOLATED
THUNDER...BUT NOT CONFIDENT MUCH OF THAT WILL HAPPEN.
AS ODILE CONTINUES TO SHIFT EASTWARD AND LOSE ITS IDENTITY...ITS
POOL OF MOISTURE WILL REMAIN OVER WEST TEXAS ON SATURDAY.
MEANWHILE...THE NEXT UPPER LOW WILL TAKE SHAPE OFF THE COAST OF
CALI...AND A WEAK UPPER HIGH WILL BEGIN TO BUILD OVER NM. AS A
RESULT...LOW TO MID LEVEL FLOW WILL BECOME EASTERLY. THOUGH THE
DAYTIME HOURS SHOULD BE RELATIVELY QUIET IN TERMS OF CONVECTION...AS
THE POOL OF MOISTURE IS ADVECTED WESTWARD INTO THE PLAINS...UP SLOPE
FLOW SHOULD ALLOW FOR SHOWERS AND PERHAPS SOME THUNDERSTORMS TO
DEVELOP LATE IN THE AFTN AND EVENING. SHOULD ALSO SEE AN EAST CANYON
WIND PICK UP IN THE RIO GRANDE VALLEY WITH BREEZY TO WINDY
CONDITIONS EXPECTED.
SUNDAY CONTINUES TO TREND TOWARD MORE WIDESPREAD PRECIPITATION AS
THE UPPER LOW EJECTS NEWD OVER THE GREAT BASIN AND LOW/MID LEVEL
MOISTURE CONTINUES TO BE ADVECTED INTO NM FROM THE S AND SE.
INCREASED POPS AREA WIDE...THOUGH GENERALLY STAY A BIT CONSERVATIVE.
WESTERLY FLOW WILL RETURN ON MONDAY...GENERALLY AT THE BASE OF THE
TROUGH/LOW MOVING ACROSS THE CENTRAL/NORTHERN ROCKIES. DRIER AIR WILL
START TO MOVE INTO THE NW BUT STILL A FAIR AMOUNT OF SHOWER AND
THUNDERSTORM ACTIVITY IS EXPECTED ELSEWHERE. THE TROUGH AXIS WILL
PASS MONDAY NIGHT...AND FLOW WILL BECOME MORE NORTHWESTERLY. THIS
SHOULD TEMPORARILY HALT ANY MONSOONAL MOISTURE FROM MOVING NORTHWARD.
A WEAK UPPER HIGH WILL DEVELOP OVER NM FOR THE MIDDLE TO LATTER HALF
OF THE WORK WEEK...THOUGH ENOUGH MOISTURE SHOULD BE AROUND TO
SUPPORT A FEW STORMS. THE 12Z GFS AND LAST NIGHTS ECMWF BOTH SHOW A
LARGE TROUGH MOVING INTO THE WESTERN US NEXT FRIDAY THRU THE
WEEKEND. THIS SCENARIO WOULD BRING UP ANOTHER BOUT OF MONSOONAL
MOISTURE FOR NM NEXT WEEKEND. HOWEVER...THE 12Z ECMWF DOES NOT SHOW
THE TROUGH AS FAR SOUTH...THUS NOT AS MUCH MOISTURE ADVECTION
NORTHWARD. STAY TUNED.
34
&&
.FIRE WEATHER...
REMNANTS OF ODILE WILL KEEP HIGH HUMIDITY AND SCATTERED SHOWERS
WITH WETTING RAIN REST OF THE AFTERNOON INTO TONIGHT FOR AREAS EAST
OF THE CENTRAL MOUNTAIN CHAIN. EASTERLY FLOW WILL RETURN ACROSS
THE EASTERN PLAINS SATURDAY INCREASING LOW LEVEL RH ACROSS THE
NORTHEAST HALF. DRYING VIA A MID LEVEL DRY INTRUSION EXPECTED
ELSEWHERE...ESPECIALLY WESTERN AREAS. THE BEST CHANCE OF WETTING
RAIN WOULD BE FOUND ACROSS THE SOUTHEAST. GAP WIND GUSTS RANGING
FROM 30 TO 45 MPH WILL BE EXPECTED ALONG THE RIO GRANDE VALLEY
SATURDAY EVENING INTO EARLY SUNDAY MORNING.
RESIDUAL MOISTURE AND A MODERATELY STRONG UPPER LEVEL LOW TO OUR
WEST WILL ENHANCE WETTING RAIN POTENTIAL AREA WIDE FOR SUNDAY.
GREATEST EMPHASIS ACROSS SOUTH CENTRAL AND SOUTHEAST AREAS.
TEMPERATURES WILL COOL 5 TO 10 DEGREES AREA WIDE BUT REMAIN NEAR
NORMAL ACROSS THE NORTHWESTERN HALF OF THE STATE. EASTERLY WINDS
WILL CONTINUE TO BE BREEZY. VENTILATION RATES LOOK TO BE
FAIR TO GOOD FOR AREAS NORTH OF THE INTERSTATE 40 CORRIDOR.
MONDAY WILL STILL SEE WETTING RAIN CHANCES AND BELOW NORMAL
TEMPERATURES IN THE EAST...LESS WETTING RAIN POTENTIAL WITH NEAR
NORMAL TEMPERATURES TO THE WEST. VENTILATION NOT EXPECTED TO CHANGE
A LOT BETWEEN SUNDAY TO MONDAY WITH BETTER READINGS ALONG AND NORTH
OF I40.
MODELS REMAIN CONSISTENT WITH DEVELOPING A DRYING TREND OVER THE
AREA STARTING TUESDAY ALTHOUGH A WEAK FRONTAL BOUNDARY IS STILL
ANTICIPATED MID WEEK AND FAVOR THE EAST SLOPES OF THE CENTRAL MTNS
EASTWARD. VENTILATION IS EXPECTED TO LOWER SOME TUESDAY/WEDNESDAY
BUT NOT FALL OUT OF SIGHT. MODELS COULD IMPROVE THE NUMBERS AS WE
GET CLOSER TO THAT PERIOD.
THE NEXT UPPER TROUGH STILL ON TAP FOR LATE WEEK INTO THE FOLLOWING
WEEKEND. MODELS REMAIN A LITTLE DIFFERENT IN TERMS OF TIMING AND
STRENGTH OF IMPACTS. THE GFS IS MUCH DEEPER AND MORE PROGRESSIVE
WITH THE TROUGH THUS SOME WIND IMPACTS POSSIBLE AHEAD OF IT. THIS
IMPACTS VENTILATION RATES. ECMWF IS A BIT SLOWER. LOWER CONFIDENCE
PERIOD FOR LATE WEEK INTO NEXT WEEK AT THIS TIME.
32/50
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
33
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1009 AM EDT SAT SEP 20 2014
.SYNOPSIS...
HIGH PRESSURE OFF THE COAST OF NEW ENGLAND WILL BRING MILD...DRY
AND GUSTY CONDITIONS TO THE REGION TODAY. AS LOW PRESSURE APPROACHES
FROM THE WEST THERE WILL BE AN INCREASING CHANCE OF SHOWERS LATER
TONIGHT...WITH WIDESPREAD SHOWER DEVELOPING ON SUNDAY AS A COLD
FRONT SWEEPS THROUGH THE REGION. THIS FRONT WILL CLEAR THE AREA
DURING MONDAY WITH SOME LINGERING SHOWERS ACROSS THE HIGHER
TERRAIN THROUGH MID-DAY...THEN IT LOOKS AS IF WE WILL BE IN FOR AN
EXTENDED PERIOD OF DRY WEATHER NEXT WEEK AS A LARGE UPPER RIDGE
BUILDS EAST FROM THE MIDWEST.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 1008 AM EDT SATURDAY...PRIMARY CHANGES WITH THIS UPDATE WAS
TO OFFER A MORE PESSIMISTIC FORECAST FOR SOUTHERN/EASTERN
VT...WITH UPWARD ADJUSTMENTS TO SKY COVER FOR MUCH OF THE AFTN
HOURS AND ACCORDINGLY LOWERED HIGHS IN THIS GENERAL AREA.
STILL SHAPING UP TO BE A BREEZY SATURDAY WITH STRONG SOUTHERLY
PRESSURE GRADIENT IN PLACE. OVERCAST SKIES THAT ADVECTED
NORTHEASTWARD OVERNIGHT STILL CONTINUES TO PLAGUE MOST OF THE
NORTH COUNTRY THIS MORNING PER VISIBLE IMAGERY. A NARROW AXIS OF
"CLEARING"/PARTLY CLOUDY SKIES EXTENDED ACROSS THE ST. LAWRENCE
VALLEY...FAR NORTHERN CHAMPLAIN VALLEY INTO THE NORTHERN GREENS.
STRONG LOW- LEVEL SOUTH/SOUTHEAST FLOW HELPING TO MAINTAIN LOWER
MOISTURE AND THINK THIS WILL CONTINUE TO BE THE GENERAL IDEA FOR
TODAY. LATEST RAP 0-1KM RH PROGS SUGGEST OVERCAST WILL BE VERY
SLOW TO LIFT ACROSS INTERIOR CENTRAL AND SOUTHERN VT TODAY. HIGHS
MAY STRUGGLE TO REACH THE MID 60S. THAT CONTRASTS WITH EXPECTED
CONDITIONS FOR ST. LAWRENCE AND NORTHERN CHAMPLAIN VALLEYS AS MORE
BREAKS IN CLOUDS WILL ALLOW HIGHS TO RANGE FROM THE UPPER 60S TO
MID 70S.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH MONDAY/...
AS OF 408 AM EDT SATURDAY...DRY CONDITIONS CONTINUE INTO TONIGHT
AS LOW PRESSURE OVER THE GREAT LAKES SHIFTS NORTHEASTWARD INTO
CENTRAL QUEBEC BY 12Z SUNDAY. ATTENDING SURFACE COLD FRONT RUNS
PARALLEL TO THE UPPER FLOW FROM THE SOUTHWEST SO THE ASSOCIATED
PRECIP WILL TAKE AWHILE TO SHIFT EASTWARD INTO THE BTV CWA...LIKELY
REACHING THE ST. LAWRENCE VALLEY RIGHT AROUND DAYBREAK. WITH
INCREASING CLOUDS AND CONTINUED GUSTY WINDS...OVERNIGHT TEMPS WILL
BE RATHER MILD WITH LOWS ONLY IN THE MID 50S TO LOWER 60S...QUITE
A DIFFERENCE FROM FRIDAY MORNING! PRECIP SHIFTS INTO NORTHERN NEW
YORK SUNDAY MORNING BUT NOT INTO THE CHAMPLAIN VALLEY AND EASTERN
VERMONT UNTIL AFTER 18Z. SO FOR SOME...SUNDAY MORNING WILL BE
GENERALLY DRY...MAINLY ACROSS VERMONT...BUT NOT SO MUCH FOR PEOPLE
LIVING IN NORTHERN NEW YORK. HIGH TEMPS ARE A LITTLE TRICKY SUNDAY
AND WILL LARGELY DEPEND ON TIMING OF THE FRONT AND ASSOCIATED
PRECIP AND CLOUDS. HIGHS WILL PUSH A FEW DEGREES WARMER THAN THE
PREVIOUS DAY ACROSS VT IN THE LOW TO MID 70S...WHILE WESTWARD IN
CLOUDS AND PRECIP THEY`LL HOLD IN THE UPPER 60S.
COLD FRONT AND ASSOCIATED PRECIP SHIFT EAST THROUGH THE REGION
SUNDAY NIGHT BUT THE PARENT UPPER LOW LAGS BEHIND...NOT MOVING
THROUGH UNTIL MONDAY AFTERNOON. WITH LINGERING LOW LEVEL MOISTURE
AND LOW/MID LEVEL FLOW TURNING TO THE NORTHWEST FEEL WE`LL SEE
SOME UPSLOPE ENHANCEMENT TO PRECIP ALONG THE SPINE OF THE GREENS
AND NORTHERN DACKS MONDAY...WHILE DOWNSLOPE AREAS WILL LIKELY
REMAIN DRY. BY LATE AFTERNOON AND INTO THE EVENING THOUGH...HIGH
PRESSURE BEGINS TO SHIFT INTO THE GREAT LAKES REGION AND LOW/MID
LEVELS BEGIN TO DRY OUT ACROSS THE BTV CWA SUBSEQUENTLY ENDING
PRECIP. HIGHS MONDAY WILL BE BACK BELOW NORMAL POST FRONTAL
PASSAGE...AND GENERALLY RUN IN THE 50S EXCEPT FOR THE LOWER
CONNECTICUT RIVER VALLEY WHICH WILL BE IN THE LOW TO MID 60S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 301 AM EDT SATURDAY...A SIGNIFICANT PATTERN CHANGE IS
EXPECTED DURING THE LONG-TERM PERIOD WITH A TREND TOWARD TRANQUIL
WEATHER WITH TEMPERATURES ABOVE SEASONAL AVERAGES. GOOD RUN-TO-RUN
CONSISTENCY CONTINUES TO BE OBSERVED IN THE 00Z OPERATIONAL GFS
AND ECMWF.
A LINGERING MID-LEVEL TROUGH/CYCLONIC FLOW EARLY IN THE PERIOD WILL
BRING PARTLY TO MOSTLY CLOUDY CONDITIONS WITH A SLIGHT CHANCE OF A
RAIN SHOWER MONDAY NIGHT INTO TUESDAY. THE HIGHEST POPS (~25%) ARE
ACROSS THE NORTHERN MOUNTAINS DURING THE DAY TUESDAY...WITH
DEVELOPMENT OF WEAK DAYTIME INSTABILITY. ANY PRECIPITATION WILL BE
LIGHT. THEREAFTER...AN AMPLIFYING DEEP-LAYER RIDGE BUILDS EWD
FROM THE MIDWEST AND GREAT LAKES PROVIDING GENERALLY CLEAR SKIES.
WILL SEE HIGHS IN THE MID 60S WEDNESDAY...AND THEN INTO THE LOW-
MID 70S IN THE VALLEYS ON THURSDAY AND FRIDAY AS AIR MASS
MODERATES. RELATIVELY LIGHT WINDS ARE EXPECTED AS WELL. CLEAR
SKIES/LIGHT WINDS WILL LEAD TO SOME LOCAL NOCTURNAL FOG IN THE
FAVORED RIVER VALLEYS EACH NIGHT FROM TUESDAY NIGHT THROUGH
THURSDAY NIGHT. COLDEST LOW TEMPERATURES WILL BE TUESDAY
NIGHT...GENERALLY IN THE UPPER 30S TO LOWER 40S. THEREAFTER...LOWS
WILL GENERALLY BE IN THE MID-UPPER 40S IN MOST SECTIONS.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
THROUGH 12Z SUNDAY...AREAS OF MVFR CEILINGS EXPECTED THIS MORNING
AT SLK/RUT/MPV ASSOCIATED WITH STRATUS DECK. THESE CLOUDS WILL
TEND TO LIFT TO VFR BY 15-16Z WITH BETTER LOW-LEVEL MIXING.
WINDS WILL BE INCREASING FROM THE SOUTH TO SOUTHWEST...ESPECIALLY
DURING THE DAYLIGHT HOURS WITH INCREASING PRESSURE GRADIENT. WILL
ALSO BE DEALING WITH LOW-LEVEL WIND SHEAR AT PBG/SLK UNTIL LOW-
LEVELS MIX OUT AFTER 14-15Z THIS MORNING. INCLUDED LLWS IN THE TAFS
AT ABOVE MENTIONED TAF SITES NEXT FEW HRS...WITH STRONGEST SHEAR
BETWEEN 1.5-2 KFT AGL. VFR THIS AFTERNOON. COULD SEE SOME
ADDITIONAL STRATUS/3-5SM BR OVERNIGHT WITH PERIODS OF MVFR
CONDITIONS.
OUTLOOK 12Z SUNDAY THROUGH WEDNESDAY...FRONTAL SYSTEM MOVING IN
FROM THE WEST WILL BRING POTENTIAL FOR WIDELY SCATTERED RAIN
SHOWERS DURING THE DAY SUNDAY...WITH PERIODS OF MVFR CEILINGS AND
VSBYS. UPPER TROUGH REMAINS IN PLACE WITH POTENTIAL FOR SCATTERED
SHOWERS SUNDAY NIGHT INTO MONDAY. MAY SEE SOME PERIODS OF
CONTINUING MVFR CEILINGS DURING SUN NIGHT AND MONDAY. GENERALLY
TRENDING VFR MONDAY NIGHT ONWARD WITH DEVELOPING STRONG SURFACE
AND UPPER RIDGE BY MID-WEEK ACROSS THE GREAT LAKES AND NEW
ENGLAND.
&&
.MARINE...
AS OF 408 AM EDT SATURDAY...STRONG SOUTH WINDS WILL CONTINUE
ACROSS LAKE CHAMPLAIN TODAY AND RIGHT INTO SUNDAY MORNING WITH
HIGH PRESSURE TO OUR EAST AND LOW PRESSURE APPROACHING FROM THE WEST.
SPEEDS OF 20 TO 30 KNOTS ARE EXPECTED DURING THIS TIME PERIOD WITH
GUSTS AS HIGH AS 35 KNOTS AT TIMES. WAVES WILL BUILD INTO THE 2 TO
5 FOOT RANGE MAKING FOR ROUGH BOATING CONDITIONS FOR A GOOD PART
OF THE WEEKEND. AS A RESULT...A LAKE WIND ADVISORY REMAINS IN EFFECT
THROUGH AT LEAST SUNDAY MORNING.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...LAHIFF/LOCONTO
SHORT TERM...LAHIFF
LONG TERM...BANACOS
AVIATION...BANACOS
MARINE...LAHIFF
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
303 AM EDT SAT SEP 20 2014
.SYNOPSIS...
HIGH PRESSURE WILL CONTINUE TO BRING DRY WEATHER TO THE NORTH
COUNTRY TONIGHT...BUT TEMPERATURES WILL NOT BE AS COLD AS LAST
NIGHT. LOOKING FOR WARMER...WINDIER...AND WETTER CONDITIONS THIS
WEEKEND. HIGHS SATURDAY AND SUNDAY WILL BE IN THE 60S TO LOWER
70S. WINDS WILL BE INCREASING DURING THE DAY ON SATURDAY WITH
GUSTS IN THE 30 TO 40 MPH RANGE. EVENTUALLY RAIN WILL MOVE IN LATE
SATURDAY NIGHT AND ESPECIALLY THROUGHOUT THE DAY ON SUNDAY WITH
WIDESPREAD RAIN EXPECTED SUNDAY AFTERNOON AND NIGHT.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
AS OF 1027 PM EDT FRIDAY...MINOR ADJUSTMENTS TO HOURLY T/TD DATA
AS OF THE 10 O`CLOCK HOUR TO ACCOUNT FOR CURRENT OBSERVATIONAL
TRENDS. SOUTHERLY RETURN FLOW HAS COMMENCED WITH SOME
AREAS...PARTICULARLY THE CHAMPLAIN AND ST LAWRENCE VALLEYS HAVING
LIKELY ALREADY EXPERIENCED THEIR OVERNIGHT LOWS AS READINGS SLOWLY
CLIMB OVERNIGHT. OTHER AREAS HAVE DECOUPLED SO MORE OF A TYPICAL
DIURNAL TREND EXPECTED...NAMELY ERN VT AND PORTIONS OF THE
ADIRONDACKS. CASE IN POINT TRUSTY SARANAC LAKE ALREADY AT THE
FREEZING MARK. HAVE A GREAT NIGHT. PRIOR DISCUSSION FOLLOWS...
PRIOR DISCUSSION...
FORECAST REMAINS IN GOOD SHAPE AS WE PROGRESS INTO THE EVENING
HOURS. CLEAR SKIES WILL GRADUALLY GIVE WAY TO SOME HIGH CLOUDS
(ESPECIALLY NORTH) OVERNIGHT AS SURFACE HIGH PRESSURE SLIDES
OFFSHORE AS SOUTH/SOUTHWESTERLY RETURN FLOW BEGINS IN EARNEST
ALOFT...NOT AS MUCH AT THE SURFACE. NONETHELESS READINGS WILL BE
MILDER TONIGHT THAN LAST NIGHT GIVEN WARM THERMAL RESPONSE THROUGH
THE 925-850 MB LEVEL. STUCK CLOSE TO LATEST RAP 500 MB RH PROGS
WHICH APPEARS TO BE HANDLING THICKER MID LEVEL CLOUDS OFF TO OUR
NORTH...AND ITS SUBSEQUENT PROGRESSION RATHER WELL THIS EVENING.
LOWS REMAIN ON TRACK...RANGING FROM THE MID TO UPPER 30S IN ERN
VT...UPPER 30S TO LOWER 40S DACKS...AND SOLIDLY IN THE 40S FOR THE
CHAMPLAIN AND ST LAWRENCE VALLEYS.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH MONDAY/...
AS OF 336 PM EDT FRIDAY...PRESSURE GRADIENT WILL CONTINUE TO
STRENGTHEN FROM THE SOUTH AND SOUTHWEST DURING THE DAY ON
SATURDAY. WHILE THIS WILL PROMOTE LOW LEVEL WARM AIR
ADVECTION...BREEZY TO WINDY CONDITIONS WILL DEVELOP. SO WHILE
HIGHS WILL BE IN THE MID 60S TO THE LOWER 70S...THE WINDS WILL NOT
ALLOW FOR IT TO FEEL THAT WARM WITH GUSTS IN THE 25 TO 35 MPH
RANGE AND EVEN SOME 40 MPH GUSTS IN THE SAINT LAWRENCE VALLEY. DRY
WEATHER IS EXPECTED DURING THE DAY ON SATURDAY...BUT THAT WILL
CHANGE AS AN UPPER LEVEL TROUGH OF LOW PRESSURE DEVELOPS OVER THE
UPPER MIDWEST. THIS FEATURE WILL BEGIN TO SHARPEN UP SATURDAY
NIGHT WHICH WILL ULTIMATELY SLOW THE ONSET OF THE PRECIPITATION
DOWN. CAN SEE A CHANCE OF SHOWERS LATE SATURDAY NIGHT OVER
NORTHERN NEW YORK...BUT THE STEADIER AND MORE WIDESPREAD SHOWERS
WILL NOT MOVE INTO THE ENTIRE AREA UNTIL LATER SUNDAY MORNING
THROUGH SUNDAY NIGHT. THE CLOUDS AND GUSTY WINDS SATURDAY NIGHT
WILL KEEP LOW TEMPERATURES WELL ABOVE NORMAL...SO IT WILL NOT TAKE
MUCH ON SUNDAY FOR HIGHS TO GET RIGHT BACK INTO THE MID 60S TO
LOWER 70S. THE UPPER TROUGH WILL BE SLOW TO MOVE EAST OF THE AREA
SUNDAY NIGHT...SO SHOWERS SHOULD BE FAIRLY WIDESPREAD SUNDAY
EVENING BEFORE GRADUALLY TAPERING OFF AFTER MIDNIGHT.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 301 AM EDT SATURDAY...A SIGNIFICANT PATTERN CHANGE IS
EXPECTED DURING THE LONG-TERM PERIOD WITH A TREND TOWARD TRANQUIL
WEATHER WITH TEMPERATURES ABOVE SEASONAL AVERAGES. GOOD RUN-TO-RUN
CONSISTENCY CONTINUES TO BE OBSERVED IN THE 00Z OPERATIONAL GFS
AND ECMWF.
A LINGERING MID-LEVEL TROUGH/CYCLONIC FLOW EARLY IN THE PERIOD WILL
BRING PARTLY TO MOSTLY CLOUDY CONDITIONS WITH A SLIGHT CHANCE OF A
RAIN SHOWER MONDAY NIGHT INTO TUESDAY. THE HIGHEST POPS (~25%) ARE
ACROSS THE NORTHERN MOUNTAINS DURING THE DAY TUESDAY...WITH
DEVELOPMENT OF WEAK DAYTIME INSTABILITY. ANY PRECIPITATION WILL BE
LIGHT. THEREAFTER...AN AMPLIFYING DEEP-LAYER RIDGE BUILDS EWD
FROM THE MIDWEST AND GREAT LAKES PROVIDING GENERALLY CLEAR SKIES.
WILL SEE HIGHS IN THE MID 60S WEDNESDAY...AND THEN INTO THE LOW-
MID 70S IN THE VALLEYS ON THURSDAY AND FRIDAY AS AIR MASS
MODERATES. RELATIVELY LIGHT WINDS ARE EXPECTED AS WELL. CLEAR
SKIES/LIGHT WINDS WILL LEAD TO SOME LOCAL NOCTURNAL FOG IN THE
FAVORED RIVER VALLEYS EACH NIGHT FROM TUESDAY NIGHT THROUGH
THURSDAY NIGHT. COLDEST LOW TEMPERATURES WILL BE TUESDAY
NIGHT...GENERALLY IN THE UPPER 30S TO LOWER 40S. THEREAFTER...LOWS
WILL GENERALLY BE IN THE MID-UPPER 40S IN MOST SECTIONS.
&&
.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
THROUGH 12Z SUNDAY...VFR CONDITIONS ARE EXPECTED THROUGH THE
PERIOD...THOUGH THERE WILL BE AN INCREASE IN MID-UPPER LEVEL
CLOUDS THROUGH THE DAYLIGHT HOURS AREAWIDE. ALSO WATCHING SOME
DEVELOPING STRATUS ACROSS E-CENTRAL NY...WHICH WILL IMPACT RUT/MPV
AT TIMES THIS MORNING WITH SCT-BKN040-050. NO PRECIPITATION IS
EXPECTED THROUGH THE PERIOD. WINDS WILL BE INCREASING FROM THE
SOUTH TO SOUTHWEST...ESPECIALLY DURING THE DAYLIGHT HOURS WITH
INCREASING PRESSURE GRADIENT. AT BTV...WINDS ALREADY 10KTS AND
WILL INCREASE TO 15G25KT AFTER 13-14Z. WILL ALSO BE DEALING WITH
LOW-LEVEL WIND SHEAR AT PBG/MSS/SLK UNTIL LOW-LEVELS MIX OUT AFTER
12Z THIS MORNING. INCLUDED LLWS IN THE TAFS AT ABOVE MENTIONED
TAF SITES THIS MORNING...WITH STRONGEST SHEAR BETWEEN 1.5-2 KFT
AGL.
OUTLOOK 12Z SUNDAY THROUGH WEDNESDAY...FRONTAL SYSTEM MOVING IN
FROM THE WEST WILL BRING POTENTIAL FOR WIDELY SCATTERED RAIN
SHOWERS DURING THE DAY SUNDAY...WITH PERIODS OF MVFR CEILINGS AND
VSBYS. UPPER TROUGH REMAINS IN PLACE WITH POTENTIAL FOR SCATTERED
SHOWERS SUNDAY NIGHT INTO MONDAY. MAY SEE SOME PERIODS OF
CONTINUING MVFR CEILINGS DURING SUN NIGHT AND MONDAY. GENERALLY
TRENDING VFR MONDAY NIGHT ONWARD WITH DEVELOPING STRONG SURFACE
AND UPPER RIDGE BY MID-WEEK ACROSS THE GREAT LAKES AND NEW
ENGLAND.
&&
.MARINE...
STRONG SOUTH TO SOUTHWEST WINDS WILL DEVELOP AFTER MIDNIGHT TONIGHT AND
CONTINUE RIGHT INTO SUNDAY MORNING. SPEEDS WILL INCREASE INTO THE
20 TO 30 KNOT RANGE DURING THIS TIME PERIOD WITH GUSTS AS HIGH AS
35 KNOTS SATURDAY NIGHT AND SUNDAY MORNING. WAVES WILL BUILD INTO
THE 2 TO 5 FOOT RANGE MAKING FOR ROUGH BOATING CONDITIONS FOR A
GOOD PART OF THE WEEKEND. AS A RESULT...A LAKE WIND ADVISORY IS IN
EFFECT FROM MIDNIGHT TONIGHT RIGHT THROUGH SUNDAY MORNING.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...EVENSON
NEAR TERM...JMG
SHORT TERM...EVENSON
LONG TERM...BANACOS
AVIATION...BANACOS
MARINE...EVENSON
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
137 AM EDT SAT SEP 20 2014
.SYNOPSIS...
HIGH PRESSURE WILL CONTINUE TO BRING DRY WEATHER TO THE NORTH
COUNTRY TONIGHT...BUT TEMPERATURES WILL NOT BE AS COLD AS LAST
NIGHT. LOOKING FOR WARMER...WINDIER...AND WETTER CONDITIONS THIS
WEEKEND. HIGHS SATURDAY AND SUNDAY WILL BE IN THE 60S TO LOWER
70S. WINDS WILL BE INCREASING DURING THE DAY ON SATURDAY WITH
GUSTS IN THE 30 TO 40 MPH RANGE. EVENTUALLY RAIN WILL MOVE IN LATE
SATURDAY NIGHT AND ESPECIALLY THROUGHOUT THE DAY ON SUNDAY WITH
WIDESPREAD RAIN EXPECTED SUNDAY AFTERNOON AND NIGHT.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
AS OF 1027 PM EDT FRIDAY...MINOR ADJUSTMENTS TO HOURLY T/TD DATA
AS OF THE 10 O`CLOCK HOUR TO ACCOUNT FOR CURRENT OBSERVATIONAL
TRENDS. SOUTHERLY RETURN FLOW HAS COMMENCED WITH SOME
AREAS...PARTICULARLY THE CHAMPLAIN AND ST LAWRENCE VALLEYS HAVING
LIKELY ALREADY EXPERIENCED THEIR OVERNIGHT LOWS AS READINGS SLOWLY
CLIMB OVERNIGHT. OTHER AREAS HAVE DECOUPLED SO MORE OF A TYPICAL
DIURNAL TREND EXPECTED...NAMELY ERN VT AND PORTIONS OF THE
ADIRONDACKS. CASE IN POINT TRUSTY SARANAC LAKE ALREADY AT THE
FREEZING MARK. HAVE A GREAT NIGHT. PRIOR DISCUSSION FOLLOWS...
PRIOR DISCUSSION...
FORECAST REMAINS IN GOOD SHAPE AS WE PROGRESS INTO THE EVENING
HOURS. CLEAR SKIES WILL GRADUALLY GIVE WAY TO SOME HIGH CLOUDS
(ESPECIALLY NORTH) OVERNIGHT AS SURFACE HIGH PRESSURE SLIDES
OFFSHORE AS SOUTH/SOUTHWESTERLY RETURN FLOW BEGINS IN EARNEST
ALOFT...NOT AS MUCH AT THE SURFACE. NONETHELESS READINGS WILL BE
MILDER TONIGHT THAN LAST NIGHT GIVEN WARM THERMAL RESPONSE THROUGH
THE 925-850 MB LEVEL. STUCK CLOSE TO LATEST RAP 500 MB RH PROGS
WHICH APPEARS TO BE HANDLING THICKER MID LEVEL CLOUDS OFF TO OUR
NORTH...AND ITS SUBSEQUENT PROGRESSION RATHER WELL THIS EVENING.
LOWS REMAIN ON TRACK...RANGING FROM THE MID TO UPPER 30S IN ERN
VT...UPPER 30S TO LOWER 40S DACKS...AND SOLIDLY IN THE 40S FOR THE
CHAMPLAIN AND ST LAWRENCE VALLEYS.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH SUNDAY NIGHT/...
AS OF 336 PM EDT FRIDAY...PRESSURE GRADIENT WILL CONTINUE TO
STRENGTHEN FROM THE SOUTH AND SOUTHWEST DURING THE DAY ON
SATURDAY. WHILE THIS WILL PROMOTE LOW LEVEL WARM AIR
ADVECTION...BREEZY TO WINDY CONDITIONS WILL DEVELOP. SO WHILE
HIGHS WILL BE IN THE MID 60S TO THE LOWER 70S...THE WINDS WILL NOT
ALLOW FOR IT TO FEEL THAT WARM WITH GUSTS IN THE 25 TO 35 MPH
RANGE AND EVEN SOME 40 MPH GUSTS IN THE SAINT LAWRENCE VALLEY. DRY
WEATHER IS EXPECTED DURING THE DAY ON SATURDAY...BUT THAT WILL
CHANGE AS AN UPPER LEVEL TROUGH OF LOW PRESSURE DEVELOPS OVER THE
UPPER MIDWEST. THIS FEATURE WILL BEGIN TO SHARPEN UP SATURDAY
NIGHT WHICH WILL ULTIMATELY SLOW THE ONSET OF THE PRECIPITATION
DOWN. CAN SEE A CHANCE OF SHOWERS LATE SATURDAY NIGHT OVER
NORTHERN NEW YORK...BUT THE STEADIER AND MORE WIDESPREAD SHOWERS
WILL NOT MOVE INTO THE ENTIRE AREA UNTIL LATER SUNDAY MORNING
THROUGH SUNDAY NIGHT. THE CLOUDS AND GUSTY WINDS SATURDAY NIGHT
WILL KEEP LOW TEMPERATURES WELL ABOVE NORMAL...SO IT WILL NOT TAKE
MUCH ON SUNDAY FOR HIGHS TO GET RIGHT BACK INTO THE MID 60S TO
LOWER 70S. THE UPPER TROUGH WILL BE SLOW TO MOVE EAST OF THE AREA
SUNDAY NIGHT...SO SHOWERS SHOULD BE FAIRLY WIDESPREAD SUNDAY
EVENING BEFORE GRADUALLY TAPERING OFF AFTER MIDNIGHT.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 336 PM EDT FRIDAY...NORTHWEST FLOW ALOFT WILL EXIST OVER THE
AREA MONDAY AND TUESDAY. THERE MAY BE SOME LINGERING SHOWERS
MONDAY MORNING...ESPECIALLY OVER VERMONT...BUT DRIER WEATHER IS
EXPECTED TO DEVELOP MONDAY AFTERNOON THROUGH TUESDAY. THE
NORTHWEST FLOW ALOFT WILL RESULT IN BELOW NORMAL HIGH
TEMPERATURES. LARGE UPPER LEVEL RIDGE BUILDS INTO THE REGION
WEDNESDAY THROUGH FRIDAY. THIS WILL RESULT IN A WARMING TREND WITH
HIGH TEMPERATURES AT OR ABOVE SEASONAL NORMALS THURSDAY AND
FRIDAY. DRY WEATHER WILL ALSO EXIST WEDNESDAY THROUGH FRIDAY.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
THROUGH 12Z SUNDAY...VFR CONDITIONS ARE EXPECTED THROUGH THE
PERIOD...THOUGH THERE WILL BE AN INCREASE IN MID-UPPER LEVEL
CLOUDS THROUGH THE DAYLIGHT HOURS AREAWIDE. ALSO WATCHING SOME
DEVELOPING STRATUS ACROSS E-CENTRAL NY...WHICH WILL IMPACT RUT/MPV
AT TIMES THIS MORNING WITH SCT-BKN040-050. NO PRECIPITATION IS
EXPECTED THROUGH THE PERIOD. WINDS WILL BE INCREASING FROM THE
SOUTH TO SOUTHWEST...ESPECIALLY DURING THE DAYLIGHT HOURS WITH
INCREASING PRESSURE GRADIENT. AT BTV...WINDS ALREADY 10KTS AND
WILL INCREASE TO 15G25KT AFTER 13-14Z. WILL ALSO BE DEALING WITH
LOW-LEVEL WIND SHEAR AT PBG/MSS/SLK UNTIL LOW-LEVELS MIX OUT AFTER
12Z THIS MORNING. INCLUDED LLWS IN THE TAFS AT ABOVE MENTIONED
TAF SITES THIS MORNING...WITH STRONGEST SHEAR BETWEEN 1.5-2 KFT
AGL.
OUTLOOK 12Z SUNDAY THROUGH WEDNESDAY...FRONTAL SYSTEM MOVING IN
FROM THE WEST WILL BRING POTENTIAL FOR WIDELY SCATTERED RAIN
SHOWERS DURING THE DAY SUNDAY...WITH PERIODS OF MVFR CEILINGS AND
VSBYS. UPPER TROUGH REMAINS IN PLACE WITH POTENTIAL FOR SCATTERED
SHOWERS SUNDAY NIGHT INTO MONDAY. MAY SEE SOME PERIODS OF
CONTINUING MVFR CEILINGS DURING SUN NIGHT AND MONDAY. GENERALLY
TRENDING VFR MONDAY NIGHT ONWARD WITH DEVELOPING STRONG SURFACE
AND UPPER RIDGE BY MID-WEEK ACROSS THE GREAT LAKES AND NEW
ENGLAND.
&&
.MARINE...
STRONG SOUTH TO SOUTHWEST WINDS WILL DEVELOP AFTER MIDNIGHT TONIGHT AND
CONTINUE RIGHT INTO SUNDAY MORNING. SPEEDS WILL INCREASE INTO THE
20 TO 30 KNOT RANGE DURING THIS TIME PERIOD WITH GUSTS AS HIGH AS
35 KNOTS SATURDAY NIGHT AND SUNDAY MORNING. WAVES WILL BUILD INTO
THE 2 TO 5 FOOT RANGE MAKING FOR ROUGH BOATING CONDITIONS FOR A
GOOD PART OF THE WEEKEND. AS A RESULT...A LAKE WIND ADVISORY IS IN
EFFECT FROM MIDNIGHT TONIGHT RIGHT THROUGH SUNDAY MORNING.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...EVENSON
NEAR TERM...JMG
SHORT TERM...EVENSON
LONG TERM...EVENSON
AVIATION...BANACOS
MARINE...EVENSON
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
630 PM EDT SAT SEP 20 2014
.SYNOPSIS...
HIGH PRESSURE BREAKS DOWN ACROSS THE AREA EARLY TONIGHT AS A LARGE
AREA OF LOW PRESSURE LIFTS NORTHEAST ALONG THE SOUTHERN US COAST
TONIGHT THROUGH THE DAY ON SUNDAY. A COLD FRONT WILL MOVE THROUGH
MONDAY. HIGH PRESSURE BEHIND THE FRONT WILL BUILD IN BEHIND THE
FRONT TO THE NORTH OF THE AREA AND REMAIN THERE THROUGH LATE WEEK.
&&
.NEAR TERM /REST OF THE NIGHT/...
AS OF 630 PM SAT...LARGE AREA OF MODERATE TO OCNL HEAVY RAIN
MOVING ONSHORE ACROSS OUTER BANKS/CARTERET COUNTY EARLY THIS
EVENING. THIS IN ASSOCIATION WITH ENHANCED MID LEVEL OMEGA/FGEN
OBSERVED IN RUC X-SECTIONS. HAVE INC POPS A BIT MORE TO ACCOUNT
FOR NEAR TERM TRENDS AND EXPECTED INC IN VORT ADVECTION ALONG THE
COAST THROUGH THE NIGHT. HAVE CORRESPONDINGLY INC QPF AMOUNTS
THROUGH THE NIGHT AS DUAL POL P-RATES JIVING WITH OBSERVED RATES
OF 1 TO OCNL 2 INCHES PER HOUR. BOUTS OF HEAVY RAIN WILL CONTINUE
TO ROTATE ONSHORE THROUGH THE NIGHT AS LOW AXIS MOVES NORTHWARD
JUST OFFSHORE CONTINUING STRONG THERMAL GRADIENT AND ACTS TO GENERATE
STRONG OMEGA/FGEN. LOCALIZED FLOODING WITH THE HEAVIER SHOWERS
CERTAINLY WILL BE A THREAT...AND HAVE INCLUDED HEAVY RAIN WORDING
IN FCST GRIDS.
PREVIOUS DISCUSSION...EXPECT THE BRIEF LULL IN SHOWER ACTIVITY THIS
AFTERNOON TO NOT LAST LONG AS A LARGE AREA OF SHOWERS ASSOCIATED
WITH THE LOW LIFTING NORTHEAST OFF THE SOUTHEASTERN US COAST MAKES
ITS WAY TOWARDS THE COAST. CARRIED CATEGORICAL 80 POPS ALONG THE
IMMEDIATE COAST FOR TONIGHT FROM THE VICINITY OF LOOKOUT THROUGH
CAPE HATTERAS...ASSOCIATED WITH THE LOW AND AN UPPER TROF ACROSS
THE SOUTHEAST. PRECIPITABLE WATER VALUES WILL BE ABNORMALLY HIGH
ACROSS THE COAST TONIGHT PERHAPS A BIT ABOVE 2.25 INCHES AS A
PLUME OF TROPICAL MOISTURE STREAMS UP THE COAST. THIS IS ABOUT TWO
STANDARD DEVIATIONS ABOVE NORMAL. EXPECT TO SEE PERIODS OF VERY
HEAVY RAINFALL AS SHOWERS MOVE ACROSS THE COAST TONIGHT. THIS
COULD RESULT IN SOME MINOR FLOODING OF LOW LYING AND POOR DRAINAGE
AREAS. THE GOOD NEWS IS THE HEAVIEST PRECIPITATION SHOULD REMAIN
ALONG COASTAL AREAS...NOT PENETRATING TOO FAR INLAND. WILL SEE
EXTENSIVE CLOUD COVER ACROSS THE AREA OVERNIGHT. FOLLOWED A BLEND
OF MOS GUIDANCE WITH LOWS IN THE MID 60S INLAND TO LOWER 70S ALONG
THE COAST.
&&
.SHORT TERM /SUNDAY/...
AS OF 330 PM SAT...THE COASTAL LOW AND ASSOCIATED MOISTURE WILL
BEGIN TO DEPART THE AREA ON SUNDAY WITH DECREASING POPS FROM WEST
TO EAST THROUGH THE DAY. EXPECT RAIN TO BE OFF THE OUTER BANKS BY
AROUND MID AFTERNOON. CLOUDS WILL DECREASE FROM WEST TO EAST AS
WELL WITH CLEARING BY THE AFTERNOON MOST PLACES. AGAIN FOLLOWED A
BLEND OF MOS GUIDANCE WITH HIGHS IN THE LOW TO MID 80S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
AS OF 255 PM SATURDAY...COLD FRONT WILL APPROACH THE AREA SUNDAY
NIGHT AND SHOULD PUSH OFFSHORE SOMETIME DURING THE LATE MORNING
HOURS ON MONDAY. GFS/NAM12/ECMWF CONTINUE TO INDICATE A BROKEN
LINE OF SHOWERS AND PERHAPS A TSTM OR TWO WILL ACCOMPANY THE
FRONT. STRONG HIGH PRESSURE WILL THEN EXPAND SOUTH FROM THE GREAT
LAKES MONDAY NIGHT AND TUESDAY WITH VERY COMFORTABLE FALL LIKE
TEMPERATURES FOR MOST OF THE AREA...WITH MID/UPPER 50S INLAND AND
LOW/MID 60S COAST. GFS AND ECMWF DIVERGE FOR THE MID WEEK PERIOD
WITH THE ECMWF CUTTING OFF THE SOUTHERN PORTION OF DEEP MID-LEVEL
TROUGH OVER SOUTH CAROLINA TUESDAY AFTERNOON THROUGH WEDNESDAY
WHILE THE GFS KEEPS A BROAD TROUGH OVER THE EASTERN US. AS A
RESULT...THE ECMWF IS MUCH WETTER SHOWING PRECIPITATION EVEN ON
TUESDAY WHILE THE GFS IS DRY TUESDAY AND WEDNESDAY. HAVE TRENDED
THIS PORTION OF THE FORECAST TOWARD THE GFS WHICH HAS BEEN MORE
CONSISTENT...BUT CANNOT IGNORE THE ECMWF SOLUTION COMPLETELY WHICH
IS CLOSE TO WPC GUIDANCE...AND THUS HAVE A SMALL POP IN THE
FORECAST...MAINLY EASTERN SECTIONS WEDNESDAY. WITH INVERTED
SURFACE TROUGH MOVING TOWARD THE COAST ON THURSDAY...BETTER
AGREEMENT WITH AT LEAST A SMALL CHANCE OF RAIN ACROSS THE REGION.
WITH A VERY WEAK UPPER LEVEL FLOW AND CONTINUED FEED OF MOISTURE
FROM THE ATLANTIC ON A SOUTHEAST FLOW...WILL LIKEWISE HAVE SMALL
POPS OVER MAINLY THE EASTERN TWO-THIRDS OF THE CWA FRIDAY AND
SATURDAY. TEMPERATURES WILL REMAIN FAIRLY CONSISTENT WITH HIGHS
MID/UPPER 70S WITH A FEW LOWER 80S AND NIGHTTIME LOWS MAINLY IN
THE UPPER 50S TO MID 60S THROUGH THE PERIOD.
&&
.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
SHORT TERM /THROUGH SUNDAY/...
AS OF 630 PM SAT...LARGE AREA OF RAIN SHOWERS MOVING ONSHORE OF
THE NC COAST THIS EVENING. BULK OF WIDESPREAD HEAVY RAIN WILL
REMAIN EAST OF THE TERMINALS...THOUGH WILL SEE OCNL BOUTS OF
HEAVIER SHOWERS POSSIBLY AFFECT ESP THE KEWN AND KOAJ TAF SITES
WITH MORE SCT ACTIVITY INLAND. CIGS WILL DROP TO MVFR FROM EAST TO
WEST ACROSS EASTERN NC THIS EVENING. COULD EVEN SEE SOME IFR
CONDITIONS WITH BEST CONFIDENCE OF A FEW HOURS OF IFR CIGS AT KEWN
WHERE DEEPER LOW LEVEL MOISTURE WILL EXIST LATE TONIGHT.
CONDITIONS WILL IMPROVE RAPIDLY ON SUNDAY AS AREA OF LOW PRES
MOVES AWAY FROM THE COAST AND WINDS TURN WNW BRINGING IN MUCH
DRIER AIR.
LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 3 PM SATURDAY...COULD SEE SOME TEMPORARY REDUCTIONS TO MVFR
WITH A FEW SHOWERS ALONG THE COLD FRONT DURING THE MORNING HOURS
ON MONDAY. WITH DRY HIGH PRESSURE BUILDING IN FROM THE
NORTH...TUESDAY SHOULD BE VFR. ANTICIPATE MOSTLY VFR ON WEDNESDAY
AS WELL...AS MODEL UNCERTAINTY EXISTS BETWEEN GFS/ECMWF ON EXTENT
OF MOISTURE/PRECIPITATION INTO THE AREA. A BETTER AGREEMENT
BETWEEN MODELS EXISTS THURSDAY WITH SCATTERED SHOWERS AND
OCCASIONAL MVFR CEILINGS AND VSBYS. A MORE MOIST BOUNDARY LAYER BY
WEDNESDAY AND THURSDAY WILL ALSO LEAD TO PATCHY FOG DURING THE
LATE NIGHT AND EARLY MORNING HOURS WITH MVFR AND PSBL IFR
CONDITIONS.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/
AS OF 330 PM SAT...CONTINUED ON STRONG SIDE OF MODEL GUIDANCE FOR
THE REMAINDER OF THE AFTERNOON AND TONIGHT BLENDING THE HIGH RES
NAM/ARW INTO THE FORECAST FOR WINDS. SCA CONDITIONS WILL PERSIST ALL
COASTAL WATERS THROUGH SUNDAY. SEAS REMAIN HIGH AND HAVE JUMPED
TO 7 TO 8 FEET ACROSS PORTIONS OF THE NORTHERN AND CENTRAL WATERS
WITH 6 FOOT SEAS TO THE SOUTH. USED NWPS GUIDANCE AND HAD TO
INCREASE SLIGHTLY FOR THE EARLY PERIOD TONIGHT TO ACCOUNT FOR
HIGHER SEAS IN THE COASTAL WATERS. WILL SEE TREACHEROUS BOATING
CONDITIONS ACROSS THE COASTAL WATERS THROUGH THE DAY ON SUNDAY AS
SEAS BUILD TO 8 TO 9 FEET ACROSS THE WATERS AS THE AREA OF LOW
PRESSURE LIFTS ACROSS THE AREA.
LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 305 PM SATURDAY...AN UNSETTLED EXTENDED PERIOD EXPECTED ON
THE COASTAL WATERS AND SOUNDS. BASED ON LATEST OUTPUT FROM LOCAL
SWAN/NWPS MODEL...HAVE OPTED TO EXTEND THE SMALL CRAFT ADVISORY
NORTH OF OCRACOKE INTO MONDAY MORNING FOR SEAS. AFTER A BRIEF LULL
MONDAY/MONDAY NIGHT...WINDS/SEAS BUILD AGAIN TUESDAY INTO THURSDAY
WITH LONG FETCH NORTHEAST FLOW AROUND STRONG 1035 MB HIGH OVER
SOUTHERN NEW ENGLAND AND WEAK INVERTED TROUGH OFFSHORE. LONGER
RANGE WAVEWATCH GUIDANCE INDICATES THAT ELEVATED SEAS AND SMALL
CRAFT ADVISORY CONDITIONS ARE LIKELY TO EXTEND INTO NEXT WEEKEND.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 AM EDT MONDAY FOR AMZ150-152-154.
SMALL CRAFT ADVISORY UNTIL 9 PM EDT SUNDAY FOR AMZ156-158.
&&
$$
SYNOPSIS...RSB
NEAR TERM...RSB/TL
SHORT TERM...RSB
LONG TERM...CTC
AVIATION...RSB/CTC/TL
MARINE...RSB/CTC
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
747 AM EDT SAT SEP 20 2014
.SYNOPSIS...
HIGH PRESSURE WILL RIDGE INTO THE REGION FROM THE NORTH TODAY. LOW
PRESSURE WILL MOVE NORTHEAST SUNDAY JUST OFF THE COAST. A COLD
FRONT WILL MOVE THROUGH MONDAY. HIGH PRESSURE BEHIND THE FRONT
WILL PASS BY TO THE NORTH TUESDAY AND WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 730 AM SAT...MINOR UPDATE TO FORECAST TO CAPTURE T/TD AND
PRECIP TRENDS THIS MORNING.
1030 MB HIGH PRES CENTERED OFF THE NEW ENGLAND COAST CONTINUES TO
RIDGE SWWD INTO THE REGION WHILE AN INVERTED TROUGH OVER THE
OFFSHORE WATERS IS ADVANCING TOWARD THE COAST AND A 1012 MB LOW
PRES IS DEVELOPING OFF THE EAST COAST OF FL. MEANWHILE A WEAK
UPPER LOW RESIDES OVER THE SOUTHEAST STATES WITH A NORTHERN STREAM
SHORTWAVE TROUGH MOVING INTO THE GREAT LAKES.
THE UPPER TROUGH WILL CONTINUE TO DIG INTO THE MIDWEST AND GREAT
LAKES THROUGH THE PERIOD AND WILL BEGIN TO ABSORB THE UPPER LOW
OVER THE SOUTHEAST WHICH IN RESPONSE WILL LIFT THE SFC LOW NORTH
JUST OFF THE SOUTHEAST COAST. EXPECT THE COASTAL TROUGH TO MOVE
INTO EASTERN SECTIONS TODAY THEN GRADUALLY DISSIPATE WHILE THE SFC
LOW LIFTS NORTH TO OFF THE SC COAST BY LATE IN THE PERIOD.
A FEW SHOWERS SHOWING UP ON RADAR ACROSS THE COASTAL WATERS ASSOC
WITH THE COASTAL TROUGH AND EXPECT THESE TO CONTINUE TO ADVANCE
TOWARD THE COAST THROUGH THE MORNING. THE BEST CHANCE OF
SHOWERS...AND POSSIBLY AN ISOLATED THUNDERSTORM...WILL OCCUR
ACROSS EASTERN SECTIONS TODAY AS THE SHOWERS WILL TEND TO
DISSIPATE AS THEY MOVE INTO A DRIER AIRMASS RIDGING IN FROM THE
NORTH. IN ADDITION...COULD SEE SOME SHOWERS ASSOC WITH THE LOW TO
THE SOUTH LIFTING TOWARD THE REGION BY LATE AFTERNOON...MAINLY
AFFECTING THE CRYSTAL COAST. MOSTLY CLOUDY SKIES EXPECTED EASTERN
SECTIONS WITH VARIABLY CLOUDY SKIES TO THE WEST. HIGHS TODAY WILL
REACH A COUPLE DEGREES EITHER SIDE OF 80.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
AS OF 230 AM SAT...THE SFC LOW WILL CONTINUE TO LIFT NORTH ALONG
THE COAST TONIGHT AND MODELS IN FAIRLY CLOSE AGREEMENT WITH THE
LOW POSITIONED SE OF CAPE LOOKOUT BY 12Z SUN. SLIGHTLY IMPROVING
UPPER LEVEL SUPPORT WITH A STRENGTHENING JET STREAK JUST TO THE
NORTH COUPLED WITH LOW LEVEL CONVERGENCE NEAR THE COASTAL TROUGH
AND SFC LOW WILL BRING A DESCENT CHANCE OF SHOWERS ACROSS EASTERN
SECTIONS TONIGHT. THERE WILL LIKELY BE A SHARP GRADIENT OF PCPN
ACROSS THE REGION WITH BEST CHANCES EAST OF HIGHWAY 17 WHERE
FORCING WILL BE MORE FAVORABLE AND MOISTURE WILL BE GREATER.
MODELS NOT IN BEST AGREEMENT WITH PRECIP AMOUNTS BUT COULD SEE AS
MUCH AS 1/2 TO 1" ALONG THE IMMEDIATE COAST FROM AROUND CAPE
LOOKOUT TO OREGON INLET BUT THEN TAPER OFF RATHER QUICKLY WEST OF
A LINE FROM JACKSONVILLE TO NEW BERN TO COLUMBIA. LOWS EXPECTED IN
THE MID 60S WELL INLAND TO LOWER 70S ALONG THE COAST.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 232 AM SAT...ACTIVE PATTERN THROUGH THE FIRST PART OF THE LONG
TERM PERIOD. MODELS AGREE THAT CUT OFF UPPER LOW OVER THE FL/GA AREA
WILL MOVE UP THE COAST AS IT DEEPENS. ACCOMPANYING SURFACE LOW WILL
SKIRT THE COAST...AND IS EXPECTED TO BE ALONG THE NORTH CAROLINA
COAST SUNDAY MORNING. UPPER LEVEL ENERGY WILL BE CENTERED
OFFSHORE...THIS WILL HELP KEEP HIGH CHANCES OF PRECIPITATION
CONFINED MAINLY TO COASTAL SECTIONS. INSTABILITY LIMITED BUT CANT
COMPLETELY RULE OUT THUNDERSTORMS. PWS JUST BELOW 2 INCHES SUNDAY
MORNING...BUT QUICKLY DROPS OFF AS SYSTEM MOVES AWAY. AS SYSTEM
LIFTS NORTH OF THE AREA DURING THE DAY SUNDAY...UPPER FLOW WILL
BRIEFLY BECOME ZONAL AHEAD OF NEXT APPROACHING TROUGH.
THIS NEXT SYSTEM WILL PUSH A FRONT AHEAD OF IT THROUGH EASTERN NORTH
CAROLINA EARLY MONDAY. NOT AN AWFUL LOT OF MOISTURE EVIDENT IN THE
MODELS WITH THIS BOUNDARY...AND UPPER LEVEL ENERGY LAGS BEHIND
IT...SO WILL KEEP PRECIPITATION CHANCES LOW. HIGH PRESSURE WILL
QUICKLY BUILD IN BEHIND THE FRONT MONDAY NIGHT. HOWEVER MODELS
DIFFER A BIT AT THIS TIME PERIOD IN THE UPPER LEVEL PATTERN WITH
ECMWF DIGGING A DEEPER UPPER LEVEL TROUGH DOWN THE EAST COAST AND
THE GFSENS BEING NOT AS DEEP. THIS DOESNT APPEAR TO AFFECT THE
SURFACE PATTERN AS MODELS AGREE ON HIGH PRESSURE NORTH OF THE AREA
THROUGH THE REMAINDER OF THE WEEK. MODELS DO HINT AT A WEAK INVERTED
TROUGH ALONG THE COAST LATE IN THE WEEK. CURRENT GRIDS HAVE LOW POPS
AND WILL CONTINUE THAT TREND.
&&
.AVIATION /11Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH TONIGHT/...
AS OF 730 AM SAT...PRED VFR EXPECTED THROUGH THE TAF PERIOD.
A COASTAL TROUGH WILL MOVE INTO EASTERN NC TODAY WITH SFC LOW
PRES LIFTING NORTH ALONG THE SE COAST AND EXPECT VARIABLY CLOUDY
SKIES WITH GREATEST COVERAGE EASTERN SECTIONS. COULD SEE ISOLATED
SHOWERS TODAY AS THE COASTAL TROUGH MOVES INLAND BUT BETTER CHANCE
OF SHOWERS WILL OCCUR TONIGHT AS THE LOW LIFTS NE JUST OFF THE
COAST. COASTAL SITES WILL HAVE THE BETTER CHANCE OF RECEIVING
PRECIP WHILE PGV AND ISO COULD VERY WELL REMAIN DRY. IF HEAVIER
PRECIP DEVELOPS COULD SEE BRIEF REDUCTIONS IN CIGS/VSBYS TO MVFR
OR POSSIBLY IFR. NE FLOW WILL CONTINUE TODAY WITH GUSTS TO AROUND
15 KT POSSIBLE THIS AFTERNOON. GUIDANCE SUGGESTING FOG/STRATUS
POSSIBLE TONIGHT BUT CONFIDENCE NOT HIGH ENOUGH TO INCLUDE IN TAFS
ATTM.
LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 240 AM SAT...LOW PRESSURE WILL MOVE UP THE COAST THIS
WEEKEND...AND BE OFF THE NORTH CAROLINA COAST BY SUNDAY MORNING.
WILL HAVE SOME MVFR CIGS/VIS SUNDAY IN ASSOCIATED SHOWERS AND LOW
CLOUDS. THIS SYSTEM WILL MOVE AWAY FROM THE AREA LATE SUNDAY AS
ANOTHER SYSTEM APPROACHES FROM THE WEST. NOT TOO MUCH MOISTURE
ASSOCIATED WITH THIS FRONTAL BOUNDARY AND UPPER LEVEL ENERGY STAYS
WEST AS IT MOVES THROUGH EASTERN NORTH CAROLINA MONDAY MORNING. MAY
HAVE ISOLATED MVFR CIGS/VIS IN ANY SHOWERS THAT DEVELOP. HIGH
PRESSURE BUILDS IN BEHIND THE FRONT WITH MAINLY VFR CONDITIONS
EXPECTED MONDAY NIGHT THROUGH WEDNESDAY...HOWEVER MAY HAVE SUB VFR
CONDITIONS IN THE PREDAWN HOURS WITH NORTHEASTERLY FLOW.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/
AS OF 530 AM SAT...EXTENDED THE SCA FOR THE PAMLICO SOUND AND
WATERS SOUTH OF OCRACOKE INLET UNTIL 15Z AS OBS CONTINUE TO SHOW
FREQUENT GUSTS TO 25 KT AND SEAS UP TO 6 FT ACROSS THE COASTAL
WATERS. MOST MODELS STILL TOO QUICK TO BRING DOWN WINDS/SEAS EARLY
THIS MORNING. BLENDED HEAVILY WITH THE RUC FOR WINDS WHICH IS MUCH
STRONGER...AND PERHAPS TOO STRONG...THAN ANY OTHER MODEL BETWEEN
12-18Z...BUT SEEMS TO CAPTURE THE CURRENT CONDITIONS BETTER. IF
THE RUC DOES VERIFY LATER THIS MORNING AN EXPANSION OF TIME AND
AREA FOR THE SCA WILL BE NECESSARY.
PREVIOUS DISCUSSION...STRONG SFC HIGH PRES CONTINUES TO RIDGE
INTO THE REGION EARLY THIS MORNING BRINGING NE FLOW AROUND 10-20
KT WITH MANY AREAS SOUTH OF OREGON INLET SEEING FREQUENT GUSTS TO
AROUND 25 KT. EXPECT WINDS TO GRADUALLY DIMINISH TO AROUND 10-15
KT BY THIS AFTERNOON AS A COASTAL TROUGH MOVES INTO THE REGION
ALLOWING GRADIENTS TO WEAKEN SOME. GRADIENTS EXPECTED TO TIGHTEN
AGAIN TONIGHT...MAINLY AFTER MIDNIGHT...AS THE SFC LOW LIFTS TO
JUST OFF CAPE FEAR BY LATE TONIGHT BRINGING WINDS TO 10-20 KT AND
POSSIBLY GUSTS TO AROUND 25 KT. SEAS REMAIN TRICKY AS MODELS A
FOOT OR TWO UNDERDONE THIS PAST EVENING AND HAVE BEEN TOO QUICK TO
DISSIPATE. SEAS CURRENTLY 4-6 FT AND ARE EXPECTED TO SUBSIDE TO
BELOW SCA CRITERIA SOUTH OF OREGON INLET THIS MORNING AS GRADIENTS
WEAKEN SOME...HOWEVER THE PROLONGED NE FETCH OF WINDS ARE EXPECTED
TO KEEP SEAS ELEVATED UP TO 5-7 FT NORTH OF OREGON INLET THROUGH
THE SHORT TERM. MODELS ALSO INDICATING SEAS REBUILD UP TO 6 FT
SOUTH OF OCRACOKE INLET AFTER MIDNIGHT TONIGHT WITH GRADIENTS
TIGHTENING NEAR THE LOW LIFTING TOWARD THE REGION.
LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 252 AM SAT...SURFACE WIND WILL BE VARIABLE SUNDAY MORNING AS
LOW PRESSURE MOVES UP THE COAST AND ACROSS THE NORTH CAROLINA
COASTAL WATERS. AM EXPECTING THE LOW PRESSURE TO REMAIN JUST EAST OF
THE WATERS WITH NORTH NORTH WESTERLY FLOW. SPEEDS WILL BE 20 TO 25
KNOTS . IF LOW TRACKS FURTHER WEST...SPEEDS WILL BE LIGHT AND
DIRECTION WILL BE DEPENDENT ON WHERE THE LOW TRACKS. SEA HEIGHTS
WILL REACH SMALL CRAFT ADVISORY CRITERIA OVER MOST OF THE WATERS
WITH UP TO 8 FEET EXPECTED IN THE OUTER WATERS. AS THE LOW MOVES
AWAY FROM THE AREA LATE SUNDAY...WIND SPEED AND SEAS WILL DECREASE
BELOW SMALL CRAFT ADVISORY CRITERIA. DIRECTION WILL TURN
SOUTHWESTERLY SUNDAY NIGHT AHEAD OF NEXT APPROACHING SYSTEM. THIS
FRONT IS EXPECTED TO PASS THROUGH THE WATERS MONDAY AFTERNOON WITH
WIND BECOMING NORTH AND NORTHEASTERLY BEHIND IT AS HIGH PRESSURE
BUILDS IN. GRADIENT BETWEEN THE DEPARTING LOW PRESSURE AND BUILDING
HIGH PRESSURE WILL INCREASE WINDS TO 15 TO 20 KNOTS MONDAY NIGHT
THROUGH WEDNESDAY. MODELS HINTING AS A TROUGH DEVELOPING ALONG THE
COAST LATE WEDNESDAY...WHICH WILL HELP INCREASE WIND SPEEDS
WEDNESDAY NIGHT.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR AMZ135-
156-158.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT SUNDAY FOR AMZ150-152-154.
&&
$$
SYNOPSIS...SK
NEAR TERM...SK
SHORT TERM...SK
LONG TERM...CGG
AVIATION...CGG/SK
MARINE...CGG/SK
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
547 AM EDT SAT SEP 20 2014
.SYNOPSIS...
HIGH PRESSURE WILL RIDGE INTO THE REGION FROM THE NORTH TODAY. LOW
PRESSURE WILL MOVE NORTHEAST SUNDAY JUST OFF THE COAST. A COLD
FRONT WILL MOVE THROUGH MONDAY. HIGH PRESSURE BEHIND THE FRONT
WILL PASS BY TO THE NORTH TUESDAY AND WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 230 AM SAT...1030 MB HIGH PRES CENTERED OVER NEW ENGLAND
CONTINUES TO RIDGE SWWD INTO THE REGION WHILE AN INVERTED TROUGH
OVER THE OFFSHORE WATERS IS ADVANCING TOWARD THE COAST AND A 1014
MB LOW PRES IS DEVELOPING OFF THE EAST COAST OF FL. MEANWHILE A
WEAK UPPER LOW RESIDES OVER THE SOUTHEAST STATES WITH A NORTHERN
STREAM SHORTWAVE TROUGH MOVING INTO THE GREAT LAKES.
THE UPPER TROUGH WILL CONTINUE TO DIG INTO THE MIDWEST AND GREAT
LAKES THROUGH THE PERIOD AND WILL BEGIN TO ABSORB THE UPPER LOW
OVER THE SOUTHEAST WHICH IN RESPONSE WILL LIFT THE SFC LOW NORTH
JUST OFF THE SOUTHEAST COAST. EXPECT THE COASTAL TROUGH TO MOVE
INTO EASTERN SECTIONS TODAY THEN GRADUALLY DISSIPATE WHILE THE SFC
LOW LIFTS NORTH TO OFF THE SC COAST BY LATE IN THE PERIOD.
A FEW SHOWERS SHOWING UP ON RADAR ACROSS THE COASTAL WATERS ASSOC
WITH THE COASTAL TROUGH AND EXPECT THESE TO CONTINUE TO ADVANCE
TOWARD THE COAST THROUGH THE MORNING. THE BEST CHANCE OF
SHOWERS...AND POSSIBLY AN ISOLATED THUNDERSTORM...WILL OCCUR
ACROSS EASTERN SECTIONS TODAY AS THE SHOWERS WILL TEND TO
DISSIPATE AS THEY MOVE INTO A DRIER AIRMASS RIDGING IN FROM THE
NORTH. IN ADDITION...COULD SEE SOME SHOWERS ASSOC WITH THE LOW TO
THE SOUTH LIFTING TOWARD THE REGION BY LATE AFTERNOON...MAINLY
AFFECTING THE CRYSTAL COAST. MOSTLY CLOUDY SKIES EXPECTED EASTERN
SECTIONS WITH VARIABLY CLOUDY SKIES TO THE WEST. HIGHS TODAY WILL
REACH A COUPLE DEGREES EITHER SIDE OF 80.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
AS OF 230 AM SAT...THE SFC LOW WILL CONTINUE TO LIFT NORTH ALONG
THE COAST TONIGHT AND MODELS IN FAIRLY CLOSE AGREEMENT WITH THE
LOW POSITIONED SE OF CAPE LOOKOUT BY 12Z SUN. SLIGHTLY IMPROVING
UPPER LEVEL SUPPORT WITH A STRENGTHENING JET STREAK JUST TO THE
NORTH COUPLED WITH LOW LEVEL CONVERGENCE NEAR THE COASTAL TROUGH
AND SFC LOW WILL BRING A DESCENT CHANCE OF SHOWERS ACROSS EASTERN
SECTIONS TONIGHT. THERE WILL LIKELY BE A SHARP GRADIENT OF PCPN
ACROSS THE REGION WITH BEST CHANCES EAST OF HIGHWAY 17 WHERE
FORCING WILL BE MORE FAVORABLE AND MOISTURE WILL BE GREATER.
MODELS NOT IN BEST AGREEMENT WITH PRECIP AMOUNTS BUT COULD SEE AS
MUCH AS 1/2 TO 1" ALONG THE IMMEDIATE COAST FROM AROUND CAPE
LOOKOUT TO OREGON INLET BUT THEN TAPER OFF RATHER QUICKLY WEST OF
A LINE FROM JACKSONVILLE TO NEW BERN TO COLUMBIA. LOWS EXPECTED IN
THE MID 60S WELL INLAND TO LOWER 70S ALONG THE COAST.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 232 AM SAT...ACTIVE PATTERN THROUGH THE FIRST PART OF THE LONG
TERM PERIOD. MODELS AGREE THAT CUT OFF UPPER LOW OVER THE FL/GA AREA
WILL MOVE UP THE COAST AS IT DEEPENS. ACCOMPANYING SURFACE LOW WILL
SKIRT THE COAST...AND IS EXPECTED TO BE ALONG THE NORTH CAROLINA
COAST SUNDAY MORNING. UPPER LEVEL ENERGY WILL BE CENTERED
OFFSHORE...THIS WILL HELP KEEP HIGH CHANCES OF PRECIPITATION
CONFINED MAINLY TO COASTAL SECTIONS. INSTABILITY LIMITED BUT CANT
COMPLETELY RULE OUT THUNDERSTORMS. PWS JUST BELOW 2 INCHES SUNDAY
MORNING...BUT QUICKLY DROPS OFF AS SYSTEM MOVES AWAY. AS SYSTEM
LIFTS NORTH OF THE AREA DURING THE DAY SUNDAY...UPPER FLOW WILL
BRIEFLY BECOME ZONAL AHEAD OF NEXT APPROACHING TROUGH.
THIS NEXT SYSTEM WILL PUSH A FRONT AHEAD OF IT THROUGH EASTERN NORTH
CAROLINA EARLY MONDAY. NOT AN AWFUL LOT OF MOISTURE EVIDENT IN THE
MODELS WITH THIS BOUNDARY...AND UPPER LEVEL ENERGY LAGS BEHIND
IT...SO WILL KEEP PRECIPITATION CHANCES LOW. HIGH PRESSURE WILL
QUICKLY BUILD IN BEHIND THE FRONT MONDAY NIGHT. HOWEVER MODELS
DIFFER A BIT AT THIS TIME PERIOD IN THE UPPER LEVEL PATTERN WITH
ECMWF DIGGING A DEEPER UPPER LEVEL TROUGH DOWN THE EAST COAST AND
THE GFSENS BEING NOT AS DEEP. THIS DOESNT APPEAR TO AFFECT THE
SURFACE PATTERN AS MODELS AGREE ON HIGH PRESSURE NORTH OF THE AREA
THROUGH THE REMAINDER OF THE WEEK. MODELS DO HINT AT A WEAK INVERTED
TROUGH ALONG THE COAST LATE IN THE WEEK. CURRENT GRIDS HAVE LOW POPS
AND WILL CONTINUE THAT TREND.
&&
.AVIATION /10Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH TONIGHT/...
AS OF 230 AM SAT...PRED VFR EXPECTED THROUGH THE TAF PERIOD.
CLOUDS AND LIGHT MIXING PREVENTING FOG DEVELOPMENT THIS MORNING
BUT CANNOT RULE OUT BRIEF PERIODS OF MVFR VSBYS AT PGV WHERE SKIES
HAVE REMAINED CLEAR...DEWPOINT DEPRESSION HAVE BEEN LOW AND
DECOUPLING HAS OCCURRED AT TIMES. A COASTAL TROUGH WILL MOVE INTO
EASTERN NC TODAY WITH SFC LOW PRES LIFTING NORTH ALONG THE SE
COAST AND EXPECT VARIABLY CLOUDY SKIES WITH GREATEST COVERAGE
EASTERN SECTIONS. COULD SEE AN ISOLATED SHOWER TODAY AS THE
COASTAL TROUGH MOVES INLAND BUT BETTER CHANCE OF SHOWERS WILL
OCCUR TONIGHT AS THE LOW LIFTS NE JUST OFF THE COAST. COASTAL
SITES WILL HAVE THE BETTER CHANCE OF RECEIVING PRECIP WHILE PGV
AND ISO COULD VERY WELL REMAIN DRY. IF HEAVIER PRECIP DEVELOPS
COULD SEE BRIEF REDUCTIONS IN CIGS/VSBYS TO MVFR OR POSSIBLY IFR.
NE FLOW WILL CONTINUE TODAY WITH GUSTS TO AROUND 15 KT POSSIBLE
THIS AFTERNOON.
LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 240 AM SAT...LOW PRESSURE WILL MOVE UP THE COAST THIS
WEEKEND...AND BE OFF THE NORTH CAROLINA COAST BY SUNDAY MORNING.
WILL HAVE SOME MVFR CIGS/VIS SUNDAY IN ASSOCIATED SHOWERS AND LOW
CLOUDS. THIS SYSTEM WILL MOVE AWAY FROM THE AREA LATE SUNDAY AS
ANOTHER SYSTEM APPROACHES FROM THE WEST. NOT TOO MUCH MOISTURE
ASSOCIATED WITH THIS FRONTAL BOUNDARY AND UPPER LEVEL ENERGY STAYS
WEST AS IT MOVES THROUGH EASTERN NORTH CAROLINA MONDAY MORNING. MAY
HAVE ISOLATED MVFR CIGS/VIS IN ANY SHOWERS THAT DEVELOP. HIGH
PRESSURE BUILDS IN BEHIND THE FRONT WITH MAINLY VFR CONDITIONS
EXPECTED MONDAY NIGHT THROUGH WEDNESDAY...HOWEVER MAY HAVE SUB VFR
CONDITIONS IN THE PREDAWN HOURS WITH NORTHEASTERLY FLOW.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/
AS OF 530 AM SAT...EXTENDED THE SCA FOR THE PAMLICO SOUND AND
WATERS SOUTH OF OCRACOKE INLET UNTIL 15Z AS OBS CONTINUE TO SHOW
FREQUENT GUSTS TO 25 KT AND SEAS UP TO 6 FT ACROSS THE COASTAL
WATERS. MOST MODELS STILL TOO QUICK TO BRING DOWN WINDS/SEAS EARLY
THIS MORNING. BLENDED HEAVILY WITH THE RUC FOR WINDS WHICH IS MUCH
STRONGER...AND PERHAPS TOO STRONG...THAN ANY OTHER MODEL BETWEEN
12-18Z...BUT SEEMS TO CAPTURE THE CURRENT CONDITIONS BETTER. IF
THE RUC DOES VERIFY LATER THIS MORNING AN EXPANSION OF TIME AND
AREA FOR THE SCA WILL BE NECESSARY.
PREVIOUS DISCUSSION...STRONG SFC HIGH PRES CONTINUES TO RIDGE
INTO THE REGION EARLY THIS MORNING BRINGING NE FLOW AROUND 10-20
KT WITH MANY AREAS SOUTH OF OREGON INLET SEEING FREQUENT GUSTS TO
AROUND 25 KT. EXPECT WINDS TO GRADUALLY DIMINISH TO AROUND 10-15
KT BY THIS AFTERNOON AS A COASTAL TROUGH MOVES INTO THE REGION
ALLOWING GRADIENTS TO WEAKEN SOME. GRADIENTS EXPECTED TO TIGHTEN
AGAIN TONIGHT...MAINLY AFTER MIDNIGHT...AS THE SFC LOW LIFTS TO
JUST OFF CAPE FEAR BY LATE TONIGHT BRINGING WINDS TO 10-20 KT AND
POSSIBLY GUSTS TO AROUND 25 KT. SEAS REMAIN TRICKY AS MODELS A
FOOT OR TWO UNDERDONE THIS PAST EVENING AND HAVE BEEN TOO QUICK TO
DISSIPATE. SEAS CURRENTLY 4-6 FT AND ARE EXPECTED TO SUBSIDE TO
BELOW SCA CRITERIA SOUTH OF OREGON INLET THIS MORNING AS GRADIENTS
WEAKEN SOME...HOWEVER THE PROLONGED NE FETCH OF WINDS ARE EXPECTED
TO KEEP SEAS ELEVATED UP TO 5-7 FT NORTH OF OREGON INLET THROUGH
THE SHORT TERM. MODELS ALSO INDICATING SEAS REBUILD UP TO 6 FT
SOUTH OF OCRACOKE INLET AFTER MIDNIGHT TONIGHT WITH GRADIENTS
TIGHTENING NEAR THE LOW LIFTING TOWARD THE REGION.
LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 252 AM SAT...SURFACE WIND WILL BE VARIABLE SUNDAY MORNING AS
LOW PRESSURE MOVES UP THE COAST AND ACROSS THE NORTH CAROLINA
COASTAL WATERS. AM EXPECTING THE LOW PRESSURE TO REMAIN JUST EAST OF
THE WATERS WITH NORTH NORTH WESTERLY FLOW. SPEEDS WILL BE 20 TO 25
KNOTS . IF LOW TRACKS FURTHER WEST...SPEEDS WILL BE LIGHT AND
DIRECTION WILL BE DEPENDENT ON WHERE THE LOW TRACKS. SEA HEIGHTS
WILL REACH SMALL CRAFT ADVISORY CRITERIA OVER MOST OF THE WATERS
WITH UP TO 8 FEET EXPECTED IN THE OUTER WATERS. AS THE LOW MOVES
AWAY FROM THE AREA LATE SUNDAY...WIND SPEED AND SEAS WILL DECREASE
BELOW SMALL CRAFT ADVISORY CRITERIA. DIRECTION WILL TURN
SOUTHWESTERLY SUNDAY NIGHT AHEAD OF NEXT APPROACHING SYSTEM. THIS
FRONT IS EXPECTED TO PASS THROUGH THE WATERS MONDAY AFTERNOON WITH
WIND BECOMING NORTH AND NORTHEASTERLY BEHIND IT AS HIGH PRESSURE
BUILDS IN. GRADIENT BETWEEN THE DEPARTING LOW PRESSURE AND BUILDING
HIGH PRESSURE WILL INCREASE WINDS TO 15 TO 20 KNOTS MONDAY NIGHT
THROUGH WEDNESDAY. MODELS HINTING AS A TROUGH DEVELOPING ALONG THE
COAST LATE WEDNESDAY...WHICH WILL HELP INCREASE WIND SPEEDS
WEDNESDAY NIGHT.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR AMZ135-
156-158.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT SUNDAY FOR AMZ152-154.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT SUNDAY FOR AMZ150.
&&
$$
SYNOPSIS...SK
NEAR TERM...SK
SHORT TERM...SK
LONG TERM...CGG
AVIATION...CGG/SK
MARINE...CGG/SK
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
942 PM CDT SUN SEP 21 2014
.UPDATE...
ISSUED AT 940 PM CDT SUN SEP 21 2014
WE WILL ADD SOME PATCHY FOG LATER TONIGHT IN THE EAST. CAN/T RULE
OUT PATCHY FOG IN ANY AREA...BUT WITH WEAK RETURN FLOW ALONG AND
WEST OF THE VALLEY LATE TONIGHT...AND THE HRRR VSBYS INDICATING
BEST POTENTIAL IN THE EAST...WILL ONLY MENTION HERE FOR NOW.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 308 PM CDT SUN SEP 21 2014
TEMPERATURES WILL BE THE MAIN CHALLENGE. MODELS ARE IN GOOD
AGREEMENT. SURFACE HIGH PRESSURE WILL PROPAGATE ACROSS THE REGION
AS UPPER LEVEL RIDGING BUILDS.
CLOUDS WILL GRADUALLY DISSIPATE FROM WEST TO EAST THIS EVENING.
SATELLITE IMAGERY INDICATES THE CLOUDS EAST OF THE VALLEY ARE NOT
AS CELLULAR...AND MAY NOT DISSIPATE AS QUICKLY. LIGHT WINDS AND
CLEAR SKY WILL LEAD TO GOOD RADIATIONAL COOLING CONDITIONS...AND
EXPECT MINIMUM TEMPS IN THE 40S.
RETURN FLOW COMMENCES BY MONDAY AFTERNOON. MAX TEMPS WILL MAKE IT
INTO THE 70S.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 308 PM CDT SUN SEP 21 2014
TUESDAY-WEDNESDAY...THE UPPER CIRCULATION CURRENTLY ACROSS THE
SOUTHWEST CONUS WILL PROPAGATE THROUGH THE REGION. THE ECMWF AND
GFS HAVE COME INTO BETTER AGREEMENT REGARDING WHERE THIS FEATURE
WILL TRACK. THIS FORECASTED TRACK WOULD BRING SHOWERS INTO THE
SOUTHERN AND EASTERN FA (AND ADJUSTED POPS ACCORDINGLY). LIMITED
POPS TO A MAXIMUM OF 30 PERCENT SINCE THIS FEATURE WILL BASICALLY
BE PROPAGATING INTO AN UPPER RIDGE/DRY AIRMASS.
WEDNESDAY NIGHT-SUNDAY...THE WED NIGHT THROUGH SUNDAY PERIOD WILL
MAINLY BE DOMINATED BY A RIDGE OVER THE CENTRAL UNITED STATES.
THIS WILL LEAD TO ABOVE NORMAL TEMPS AND BREEZY AFTERNOON SOUTH
WINDS FOR THU THROUGH SAT. SOME MODELS DIFFERENCES COME INTO PLAY
BY SUNDAY BUT THE GENERAL IDEA IS FOR THE RIDGE TO SHIFT A LITTLE
FURTHER EAST BRINGING SOME CHANCES FOR RAIN TO AREAS WEST OF THE
RED RIVER.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 650 PM CDT SUN SEP 21 2014
VFR CONDITIONS AND LIGHT WINDS TONIGHT. WINDS TURN SOUTHERLY
TOMORROW AT OR UNDER 10KT. WE WILL HAVE TO MONITOR FOG POTENTIAL
WITH HIGH PRESSURE OVERHEAD TONIGHT...BUT FOR NOW CONFIDENCE LOW
IN POTENTIAL.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...DK
SHORT TERM...TG
LONG TERM...GODON/TG
AVIATION...DK
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
710 AM CDT SAT SEP 20 2014
.UPDATE...
ISSUED AT 707 AM CDT SAT SEP 20 2014
NO CHANGES WERE MADE AS TIMING OF PRECIP SEEMS GOOD BASED ON
LATEST RAP AND 06Z NAM.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 357 AM CDT SAT SEP 20 2014
TO START THE DAY...WILL HAVE SOME LOW CLOUDS IN PARTS OF NW MN AND
PATCHY CLOUDS AND FOG IN NE ND. BIG ISSUE TODAY IS UPSTREAM VORT
MAX IN EAST CENTRAL ALBERTA THAT WILL MOVE SOUTHEAST INTO WESTERN
ND AT 18Z AND THEN INTO WEST CNTRL MN AT 00Z SUN. VERY STRONG MID
AND UPPER LEVEL FORCING WITH A 80 KT 500 MB JET AND 130 KT 300 MB
JET WITH THIS VORT...ALONG WITH STRONG UPPER LEVEL DIVERGENCE
CENTERED OVER THE RED RIVER VALLEY EARLY THIS AFTN. SPC WRF AND
RUC AND LOCAL WFO FGF WRF ALL INDICATE ABOUT THE SAME SCENARIO
WITH A POTENTIAL SQUALL LINE ORGANIZING OVER NE ND NEAR NOON-EARLY
AFTN AND MOVING EAST-SOUTHEAST INTO MINNESOTA EARLY TO MID AFTN.
PEAK OF ACTIVITY VIA RADAR PROGS FROM SPC WRF WOULD INDICATE AREAS
FROM ROSEAU TO DETROIT LAKES IN THE PRIME ZONE THEN LINE WILL MOVE
EAST AND WEAKEN TOWARD 00Z JUST EAST OF THE FCST AREA. SPC DAY 1
HAS MUCH OF THE AREA IN SLIGHT RISK USING THE AFOREMENTIONED
PARAMTERS. ONE DOWNSIDE IS THAT THE LOW LEVELS WILL BE MUCH COOLER
THAN YESTERDAY AND THUS INSTABILITY PARAMETERS WILL BE PRETTY WEAK
WITH BARELY BELOW 0C SHOWWALTERS WITH SYSTEM. IT IS EXPECTED MID
AND UPPER LEVEL DYNAMICS WILL OVERCOME THIS. WIND SEEMS TO BE THE
MAIN THREAT AS 850 MB WINDS INCREASE TO 45 KTS FOR A TIME MID AFTN
JUST EAST OF THE RRV AS LINE MOVES THROUGH. THUS ANY STRONG STORM
LINE COULD EASILY MIX THIS DOWN. HAIL ALSO A THREAT DUE TO COOLING
AT 500 MB WITH SYSTEM AS TEMPS AT THAT LEVEL DROP TO -20C. TORNADO
THREAT WOULD SEEM LOW...DUE TO LACK OF SFC LOW UNLIKE YESTERDAY.
DID INCLUDE SEVERE WORDING FOR A 2-3 HOUR PERIOD ACROSS THE RRV
INTO MN IN RISK AREA BASED ON TIMING FROM SPC WRF/RUC.
SYSTEM CLEARS EAST TONIGHT...LINGERING CLOUDS IN LAKE OF THE
WOODS BUT CLEARING ELSEWHERE. SUNDAY WILL SEE CLOUDS MOST
PROMINENT IN MN FCST AREA UNDER DEPARTING 500 MB TROUGH.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 357 AM CDT SAT SEP 20 2014
SUN NIGHT INTO MONDAY WILL FEATURE GENERALLY CLEAR SKY AS HIGH
PRESSURE AND DRY AIRMASS MOVES IN.
FOR TUESDAY THROUGH FRIDAY...
LONG WAVE RIDGE OVER WESTERN NORTH AMERICA SHIFTS TO EASTERN
NORTH AMERICA BY THE END OF THE PERIOD. LONG WAVE UPPER RIDGE
PRODUCES MUCH ABOVE NORMAL HEIGHTS BY THE END OF THE PERIOD. SHORT
WAVE TROUGH OFF THE CA COAST IS FORECAST TO MOVE ACROSS ITO THE
NORTHERN PLAINS BY LATE TUE INTO WED. THE GFS AND ECMWF ARE
SIMILAR IN TIMING AT 84 HOURS THE GFS BECOMES THE FASTER SOLUTION
ON THU AND FRI. WILL PREFER THE ECMWF.
TWEAKED POPS UP A LITTLE ON TUE.
LITTLE CHANGE TO TEMPS...INCREASE TEMPS BY A DEGREE ON THU.
ESSENTIALLY NO CHANGES FROM PREVIOUS FORECAST PACKAGE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 707 AM CDT SAT SEP 20 2014
TYPICAL EARLY MORNING AREA OF LOW END MVFR/IFR CIGS ALONG WITH
PATCHES OF FOG IN THE RED RIVER VALLEY INTO MINNESOTA. THE LOW
CLOUDS/FOG WILL MIX OUT BUT REPLACE BY MID AND HIGH LEVEL MOISTURE
FROM UPPER WAVE MOVING SOUTHEAST. TRIED TO TIME BEST RISK OF TSTMS
AT TAF SITES....MOSTLY VERY LATE MORNING IN DVL AND EARLY AFTN IN
GFK AND MID AFTN TVF-FAR AND LATE AFTN BJI. WINDS MAIN ISSUE WITH
THESE STORMS AS A WEST-SOUTHWEST WIND TURNS NORTHWEST WITH LIKELY
HIGH GUSTS FOR A TIME WITH LINE OF SHOWERS/STORMS. WINDS WILL
DIMINISH THIS EVE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...RIDDLE
SHORT TERM...RIDDLE
LONG TERM...HOPPES/RIDDLE
AVIATION...RIDDLE
AREA FORECAST DISCUSSION
NWS BISMARCK ND
105 AM CDT SAT SEP 20 2014
.UPDATE...
ISSUED AT 105 AM CDT SAT SEP 20 2014
THE INHERITED FORECAST IS MAINLY ON TRACK FOR THE EARLY MORNING
FORECAST UPDATE. DID MODIFY POPS FOR THE NEXT S/WV SET TO MOVE
THROUGH THE NORTHERN PLAINS THIS MORNING. SCALED BACK ON
PRECIPITATION CHANCES TILL 09Z...HIGHER POPS ACROSS THE NORTH
DURING THE MORNING HOURS LATE TONIGHT PAST DAYBREAK SATURDAY.
UPDATE ISSUED AT 952 PM CDT FRI SEP 19 2014
CONVECTION HAS ALL BUT ENDED ACROSS WESTERN AND CENTRAL NORTH
DAKOTA WITH THE SETTING SUN. STILL AN ISOLATED SHOWER ALONG THE
MISSOURI RIVER BORDERING MONTANA...BUT THIS ACTIVITY HAS BEEN
DECREASING AND EXPECT THIS TO CONTINUE. THUS HAVE REMOVED POPS FOR
THIS EVENING. MODELS SUGGEST NEXT WAVE WILL BE MOVING INTO
SOUTHEAST SASKATCHEWAN LATE TONIGHT AND HAVE UTILIZED THE 01 UTC
RAP AS A GUIDE FOR TIMING OF THE PRECIPITATION WITH THIS WAVE.
BROUGHT SHOWERS INTO THE FAR NORTHWEST AROUND 09-10 UTC WITH
SHOWERS AND ISOLATED THUNDERSTORMS GENERALLY ALONG AND NORTH OF A
LINE FROM WILLISTON TO GARRISON TO JAMESTOWN ON SATURDAY...WITH
PRECIPITATION ENDING IN THE SOUTHERN JAMES RIVER VALLEY BY MID TO
LATE AFTERNOON.
UPDATE ISSUED AT 642 PM CDT FRI SEP 19 2014
ISOLATED THUNDERSTORMS CONTINUE TO TRACK SOUTHEAST ACROSS
BOTTINEAU AND MCHENRY COUNTIES IN NORTH CENTRAL NORTH
DAKOTA. STRONGER CELLS HAVE REMAINED OVER NORTHEAST NORTH DAKOTA
NEAR THE SURFACE LOW PRESSURE SYSTEM. GUSTY NORTHWEST WINDS BEHIND
THE LOW SHOULD DIMINISH EARLY THIS EVENING ACROSS THE WEST AND
CENTRAL. UPDATED SKY COVER AND POP GRIDS BASED ON LATEST RADAR AND
SATELLITE IMAGERY. OTHERWISE NO SIGNIFICANT UPDATES NEEDED.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 230 PM CDT FRI SEP 19 2014
SCATTERED THUNDERSTORMS NORTH THIS AFTERNOON AND EVENING...AND WINDY
CONDITIONS WITH RAIN SHOWERS SATURDAY HIGHLIGHT THE SHORT TERM FORECAST.
THE 12 UTC GLOBAL SUITE AND THE 14-15 UTC HRRR ITERATIONS CONTINUE
TO SUGGEST SCATTERED SHOWERS AND THUNDERSTORMS LATE THIS AFTERNOON
THROUGH SUNSET ALONG AND NORTH OF THE US HIGHWAY 2
CORRIDOR...BEHIND A WEAK SECONDARY COLD FRONT WITH 50S SURFACE DEWPOINTS
IN TRAIL. SEVERE CONVECTION IS NOT ANTICIPATED AND WILL FADE
QUICKLY WITH SUNSET.
FOR SATURDAY...THE SHORTWAVE CURRENTLY ACROSS WESTERN ALBERTA
THIS AFTERNOON IS FORECAST TO PROPAGATE ACROSS NORTH DAKOTA DURING
THE MORNING AND EARLY AFTERNOON. THE HIGHEST POPS ARE FOCUSED
ACROSS THE NORTH CENTRAL AND EAST...WITH THE SOUTHWEST FORECAST TO
BE PRECIPITATION FREE. DID INCLUDE AN ISOLATED THUNDER MENTION
WITH WEAK INSTABILITY. SATURDAY WILL BE WINDY WITH A TIGHT
PRESSURE GRADIENT BETWEEN THE SURFACE HIGH IN MONTANA AND LOW
PRESSURE OVER LAKE WINNIPEG. THE 12 UTC NAM/GFS BUFR SOUNDINGS
DEPICT 30-35 KTS OF FLOW AT THE TOP OF THE MIXED LAYER...WHICH
EQUATES TO BRISK NORTHWEST WINDS THAT REMAIN BELOW ADVISORY
CRITERIA.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 230 PM CDT FRI SEP 19 2014
THE LONG TERM BEGINS WITH THE WESTERN RIDGE OVER THE ROCKIES AND A
CUTOFF LOW OVER CALIFORNIA/NEVADA...WITH NORTHWEST FLOW ALOFT OVER
THE DAKOTAS. THE UPPER RIDGE MOVES EAST INTO THE PLAINS THROUGH THE
WEEKEND...WITH THE CUTOFF LOW LIFTING NORTHEASTWARD SLOWLY
COINCIDENT WITH THE UPPER RIDGE`S EASTWARD MOVEMENT. DURING THIS
TIME...SURFACE HIGH PRESSURE WILL BRING MILD AND DRY AIR TO WESTERN
AND CENTRAL NORTH DAKOTA. DRY THROUGH MONDAY NIGHT. LOW TEMPERATURES
SUNDAY MORNING FROM THE UPPER 30S WEST TO 40S CENTRAL...WARMING TO
LOWS IN THE 50S BY TUESDAY MORNING. HIGHS SUNDAY UPPER 60S TO LOWER
70S...AND IN THE 70S ON MONDAY.
BY TUESDAY THE MEANDERING CUTOFF UPPER LEVEL LOW IS FORECAST TO BE
OVER THE NORTHERN/CENTRAL PLAINS...BRINGING A CHANCE OF SHOWERS OR
THUNDERSTORMS TO THE FORECAST AREA TUESDAY AND WEDNESDAY. MEANWHILE
A LONGWAVE TROUGH DEVELOPS OVER THE WEST COAST...AND UPSTREAM
RIDGING OCCURS OVER THE PLAINS AHEAD OF THIS SYSTEM...LEADING TO A
DRY END OF THE WEEK. CONTINUED MILD WITH LOWS IN THE 50S...AND HIGHS
IN THE 70S TO AROUND 80.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 105 AM CDT SAT SEP 20 2014
VFR CONDITIONS EXPECTED ACROSS WESTERN AND CENTRAL NORTH DAKOTA
THROUGH THE 06Z TAF PERIOD. SCATTERED VFR CLOUDINESS THROUGH
SATURDAY MORNING THROUGH EARLY AFTERNOON...BASES AROUND 7-10KFT
TRACKING MAINLY FROM KMOT TO KJMS AS ANOTHER QUICK MOVING SYSTEM
MOVES THROUGH. WILL MENTION A VCSH AT KISN-KMOT-KJMS SATURDAY
MORNING. NORTHWEST FLOW WILL INCREASE AGAIN SATURDAY AFTERNOON
WITH GUSTS TO AROUND 30-35 KTS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...AYD
LONG TERM...JV
AVIATION...NH
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
557 PM EDT SAT SEP 20 2014
.SYNOPSIS...
A STRONG COLD FRONT WILL SHIFT THROUGH THE GREAT LAKES TONIGHT AND
SUNDAY WITH THE THREAT FOR SHOWERS AND THUNDERSTORMS. A MILD NIGHT
IS IN STORE AHEAD OF THE FRONT TONIGHT...WITH LOWS IN THE 60S.
COOLER AIR WILL DROP IN QUICKLY BEHIND THE FRONT SUNDAY AFTERNOON
AND NIGHT...LEADING TO SEVERAL NIGHTS WITH LOWS IN THE 40S...WITH
PERHAPS SOME UPPER 30S IN OUTLYING AREAS. MUCH OF THE WORK WEEK
WILL FEATURE STRONG HIGH PRESSURE...WHICH WILL BRING MILD
DAYS...COOL NIGHTS...AND LOW HUMIDITY. PLENTY OF SUN IS EXPECTED
THROUGH THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
UPDATE...SPED UP ARRIVAL OF RAIN CHANCES BY AN HOUR OR TWO BASED
ON TIME TRENDS FROM RADAR ON NOW WELL-DEVELOPED LINE OF CONVECTION
FROM NERN IND BACK TO WCNTL IND. MOST CONCENTRATED N-S PORTION OF
LINE WITH HISTORY OF WIND DAMAGE WILL PASS NORTH OF OUR AREA
THROUGH EARLY EVENING. REST OF LINE SEEMS TO BE STRUGGLING TO BE
SEVERE...AND WE/RE WATCHING PORTION OF THE LINE FROM LOGANSPORT
BACK TO IL BORDER AS THE PORTION THAT WILL AFFECT US. GUST FRONT
NOW KICKING SWRD FROM SEGMENT OF LINE FROM COLUMBIA CITY BACK TO
LOGANSPORT SO THIS PORTION OF LINE LIKELY TO WEAKEN. MESOA OVER
IND/OH SHOWS INSTBY DECREASING WITH EWRD EXTENT INTO ILN CWA AND WITH
SUNSET APPROACHING STILL THINK OVERALL SEVERE THREAT IS MARGINAL.
DID UPDATE HWO TO GIVE HEADS UP TO WCNTL OHIO/ECNTL IND COUNTIES
THAT A GUSTY/WEAKENING LINE OF STORMS IS LIKELY 00Z-02Z. REF
MCD#1741 THAT A NEW WATCH /IF ISSUED/ MAY GRAB A COUPLE OF OUR FAR
NWRN COUNTIES. ALSO PULLED RAIN CHANCES IN NRN KY AS CUMULUS/PVS
SHRA DOWN THERE HAVE LARGELY DISSIPATED.
PREVIOUS DISCUSSION -> SEVERAL FOCI FOR PRECIPITATION NOW THROUGH
SUNRISE ON SUNDAY MORNING. FIRST...IS IN A RELATIVELY NARROW AXIS
OF HIGHER THETA-E THAT RUNS NORTHEAST ALONG THE OHIO RIVER INTO
THE CVG AREA THIS AFTERNOON. BOUNDARY LAYER DWPTS HAVE WITHSTOOD
MIXING TO REMAIN IN THE MID 60S YIELDING SOME MARGINAL MLCAPE FROM
200-500 J/KG. CONFLUENT FLOW/VERY WEAK CONVERGENCE HAS LED TO THIS
EXTENSION OF BUOYANCY AND SOME ISOLD SHRA HAVE DEVELOPED IN THIS
AXIS AND WILL CONTINUE TO DO SO THROUGH ABT 7-8 PM TIED STRONGLY
TO THE BOUNDARY LAYER FLOW/INSTBY. HAVE PLACED A SMALL RAIN CHANCE
IN PARTS OF OUR NRN KY COUNTIES FOR THIS EVENING TO ACCOUNT FOR
THIS THREAT.
LARGER CONCERN IS STRONG COLD FRONT WHICH IS SHIFTING THROUGH
WI/IA/NRN IL ATTM ATTENDANT TO A COUPLE OF HEIGHT FALL
CENTERS...ONE IN WI THIS AFTN AND ANOTHER VERY COMPACT ONE IN ERN
ND. LOW LEVEL FORCING IS STRONG WITH THE FRONT AND ASSOCIATED PRE-
FRONTAL TROUGH...AND DEEP LAYER FLOW IS INCREASING AS THE THROUGH
AMPLIFIES WITH TIME TONIGHT.
CONVECTION HAS RECENTLY ERUPTED AS OF 19Z JUST SOUTH OF CHICAGO
AND SPC WATCH #504 ACCOMPANIES THIS INCREASE IN CONVECTION OFF TO
OUR NW. ACCORDING TO 20.12Z AWR-WRF...20.09Z SREF...AND MULTIPLE
WELL-AGREED UPON HRRR RUNS...A RATHER ROBUST LINE OF STORMS WILL
DEVELOP ALONG/AHEAD OF THE FRONT OVER THE NEXT FEW HOURS AND PUSH
EAST/NORTHEAST. ORIENTATION/MAGNITUDE /30+KTS BY TONIGHT/ OF 0-3KM
SHEAR VECTOR IS FAVORABLE FOR SOME DURATION/ORGANIZATION TO LINE
SEGMENTS WHICH CAN ORIENT IN MORE N-S FASHION OR SOME VARIATION OF
THAT. NOT SURPRISINGLY...HRRR RUNS HAVE DEMONSTRATED SPORADIC SWATHS
OF DAMAGING WIND GUSTS > 50KTS ACROSS NRN IND POTENTIALLY
INVOLVING NWRN/WCNTL OH LATER THIS EVE /AFTER 10 PM OR SO/. REALLY
LIKE THE 5% WIND CONTOUR INTO WCNTL OHIO BASED ON THE HRRR/ARW WRF
SOLUTIONS SHOWING A WEAKENING ORGANIZED LINE COMING INTO OUR AREA
AROUND 10 PM...PERHAPS WITH SOME 40-50 MPH WINDS. THIS FITS
CURRENT MESOA WHICH HAS MINIMUM OF INSTBY IN WRN OH DUE TO MIXED
DWPTS IN THE 50S...SO LINE SHOULD WEAKEN CONSIDERABLY AS IT
CROSSES INTO OHIO...DESPITE BRINGING A MODEST INCREASE IN MOISTURE
VIA ADVECTION.
STRUGGLED A LOT WITH RAIN CHANCES...FEEL CONFIDENT ENOUGH FOR
LIKELY RAIN CHANCES WITH DYING LINE INTO ABOUT THE NWRN 1/2 OF OUR
FORECAST AREA...BUT ALL CAMS/PARAMETRIZED DATA SHOWING ACTIVITY
BECOMING MORE SCT WITH TIME AS NIGHT WEARS ON. SO RAIN CHANCES
OVERNIGHT RANGE FROM A LOW CONFIDENCE 20% IN FAR SOUTH/EAST UP TO
A 70% CHANCE OR SO IN WCNTL OH. ALL WILL DEPEND HOW QUICKLY THE
INCOMING LINE WEAKENS.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
FIRST HEIGHT FALL CENTER MENTIONED ABOVE PULLS EAST OF THE AREA
SUNDAY MORNING TAKING PRIMARY CONVERGENCE/PREFRONTAL TROUGH WITH
IT THROUGH THE MORNING. RESIDUAL SHOWERS/STORMS TO CROSS THE AREA
IN THE MORNING AND THEN SCT STORMS WILL BEGIN TO BUBBLE ALONG THIS
BOUNDARY LATE MORNING/EARLY AFTERNOON AND LIKELY IN OUR FAR
SOUTH/EAST OR JUST OUT OF OUR AREA. RATHER IMPRESSIVE/NARROW DRY
SLOT SHOULD WRAP IN LATE MORNING/EARLY AFTERNOON WITH SOME
SUNSHINE BEFORE STRONG CAA SETS IN DURING THE AFTERNOON WITH THE
PASSAGE OF SECONDARY FRONT. WITH SHALLOW INSTBY DEVELOPING...COULD
SEE SOME SCT SHRA DEVELOP WITH THIS FEATURE WHICH WAS ALREADY WELL
HANDLED BY PVS FORECASTER. THIS MOST LIKELY ACROSS OUR NORTH
CLOSER TO STRONG/COMPACT SHORTWAVE DIGGING ACROSS NRN OH. DON/T
EXPECT MUCH IF ANY THUNDER AFTER ABOUT 18Z...AS INSTBY BECOMES TOO
SHALLOW FOR CHARGE SEPARATION. WILL DEFINITELY A BE A CHANGEABLE
/AUTUMN-LIKE DAY DESPITE MAX TEMPS IN THE 70S. WINDS WILL BECOME
BREEZY/GUSTY IN THE AFTN AS THE COLD ADVECTION ARRIVES AND
CHANGEABLE SKY WITH THE DRY SLOT TO LOWER CLOUDS ALONG/BEHIND THE
SECONDARY SURFACE FRONT.
AS THIS ACTION ALL CLEARS THE CWA SUNDAY NIGHT AND STRONG HIGH
PRESSURE BUILDS IN...A VERY CHILLY NIGHT IN STORE WITH LOWS WELL
INTO THE 40S IN OUR INDIANA/WRN OHIO COUNTIES AS 925MB TEMPS DROP
TO +5C IN THIS AREA BY SUNRISE ON MONDAY. SHOULD SEE A SLOW DECREASE
IN LOW CLOUDS THROUGH THE NIGHT AND LESSENING WINDS AS
WELL...GIVEN THE DEGREE OF COLD AIR INBOUND...AM A LITTLE WORRIED
I AM CLEARING THE SKIES A LITTLE TOO QUICKLY AND STRATOCUMULUS MAY
BE MORE WIDESPREAD.
MONDAY BRINGS 1024MB SURFACE HIGH PRESSURE SPRAWLING INTO THE
GREAT LAKES AND CENTERED NEAR CHICAGO BY MONDAY EVENING. SHOULD BE
PLENTY OF SUNSHINE WITH DEWPTS IN THE 40S. CONTINUED WEAK CAA
SHOULD KEEP 925MB TEMPS IN THE +8 TO +10C RANGE WHICH PER CLIMO
STUDY SUGGESTS MAX TEMPS IN THE LOW TO MID 60S MOST
AREAS...DESPITE PLENTY OF SUN. MONDAY NIGHT WILL BE COLDEST OF THE
WEEK AND WOULD NOT BE SURPRISED TO SEE COLD PRONE/OUTLYING SITES
TOUCH THE MID TO UPPER 30S AGAIN LIKE DELAWARE/MARYSVILLE ETC DID
LAST WEEK. MAY EVEN BE A TOUCH COLDER THIS TIME AROUND. LOW TEMPS
THIS NIGHT MAY STILL BE A DEGREE OR TWO TOO WARM IN GOING
FORECAST...ESPECIALLY WITH SURFACE HIGH MOVING RIGHT OVERHEAD AT
12Z AND THE VERY DRY PROFILE /PWATS RUNNING 40% OF NORMAL/. AN
IDEAL RADIATIONAL COOLING SIGNAL BEING SEEN IN THE DATA.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
MID/UPPER LEVEL RIDGE WILL REMAIN IN PLACE ACROSS THE REGION
THROUGH THE END OF THE WEEK. THIS WILL RESULT IN DRY CONDITIONS AND
FAIRLY SEASONABLE TEMPERATURES THROUGH THE LONG TERM PERIOD. AS THE
AIRMASS SLOWLY MODIFIES...HIGH TEMPERATURES WILL GRADUALLY WARM EACH
DAY...FROM THE LOW TO MID 70S MID WEEK INTO THE UPPER 70S TO AROUND
80 DEGREES BY THE WEEKEND.
&&
.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
MVFR CEILINGS PERSIST AT CVG AND LUK...OTHERWISE TAF SITES HAVE
VFR. COLD FRONT WILL BE MOVING IN LATE TONIGHT/EARLY SUNDAY. THIS
WILL BRING SCATTERED SHOWERS AND POSSIBLY MORE MVFR CEILINGS. KEPT
THUNDER OUT FOR NOW SINCE FRONT WILL BE ARRIVING AT A DIURNALLY
UNFAVORABLE TIME. WINDS WILL GUST AROUND 20 KNOTS THIS AFTERNOON
OUT OF THE SOUTHWEST. GUSTS OVER 20 KNOTS ARE EXPECTED SUNDAY
AS DIRECTION SHIFTS TO WEST ALONG THE FRONT. CVG SHOULD SEE
CONTINUED GUSTY CONDITIONS AS WINDS BECOME NORTHWEST SUNDAY
AFTERNOON BEHIND THE FRONT.
OUTLOOK...MVFR CEILINGS POSSIBLE SUNDAY NIGHT.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...BINAU
NEAR TERM...BINAU
SHORT TERM...BINAU
LONG TERM...JGL
AVIATION...CONIGLIO
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
352 PM EDT SAT SEP 20 2014
.SYNOPSIS...
A STRONG COLD FRONT WILL SHIFT THROUGH THE GREAT LAKES TONIGHT AND
SUNDAY WITH THE THREAT FOR SHOWERS AND THUNDERSTORMS. A MILD NIGHT
IS IN STORE AHEAD OF THE FRONT TONIGHT...WITH LOWS IN THE 60S.
COOLER AIR WILL DROP IN QUICKLY BEHIND THE FRONT SUNDAY AFTERNOON
AND NIGHT...LEADING TO SEVERAL NIGHTS WITH LOWS IN THE 40S...WITH
PERHAPS SOME UPPER 30S IN OUTLYING AREAS. MUCH OF THE WORK WEEK
WILL FEATURE STRONG HIGH PRESSURE...WHICH WILL BRING MILD
DAYS...COOL NIGHTS...AND LOW HUMIDITY. PLENTY OF SUN IS EXPECTED
THROUGH THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
SEVERAL FOCI FOR PRECIPITATION NOW THROUGH SUNRISE ON SUNDAY
MORNING. FIRST...IS IN A RELATIVELY NARROW AXIS OF HIGHER THETA-E
THAT RUNS NORTHEAST ALONG THE OHIO RIVER INTO THE CVG AREA THIS
AFTERNOON. BOUNDARY LAYER DWPTS HAVE WITHSTOOD MIXING TO REMAIN IN
THE MID 60S YIELDING SOME MARGINAL MLCAPE FROM 200-500 J/KG.
CONFLUENT FLOW/VERY WEAK CONVERGENCE HAS LED TO THIS EXTENSION OF
BUOYANCY AND SOME ISOLD SHRA HAVE DEVELOPED IN THIS AXIS AND WILL
CONTINUE TO DO SO THROUGH ABT 7-8 PM TIED STRONGLY TO THE BOUNDARY
LAYER FLOW/INSTBY. HAVE PLACED A SMALL RAIN CHANCE IN PARTS OF OUR
NRN KY COUNTIES FOR THIS EVENING TO ACCOUNT FOR THIS THREAT.
LARGER CONCERN IS STRONG COLD FRONT WHICH IS SHIFTING THROUGH
WI/IA/NRN IL ATTM ATTENDANT TO A COUPLE OF HEIGHT FALL
CENTERS...ONE IN WI THIS AFTN AND ANOTHER VERY COMPACT ONE IN ERN
ND. LOW LEVEL FORCING IS STRONG WITH THE FRONT AND ASSOCIATED PRE-
FRONTAL TROUGH...AND DEEP LAYER FLOW IS INCREASING AS THE THROUGH
AMPLIFIES WITH TIME TONIGHT.
CONVECTION HAS RECENTLY ERUPTED AS OF 19Z JUST SOUTH OF CHICAGO
AND SPC WATCH #504 ACCOMPANIES THIS INCREASE IN CONVECTION OFF TO
OUR NW. ACCORDING TO 20.12Z AWR-WRF...20.09Z SREF...AND MULTIPLE
WELL-AGREED UPON HRRR RUNS...A RATHER ROBUST LINE OF STORMS WILL
DEVELOP ALONG/AHEAD OF THE FRONT OVER THE NEXT FEW HOURS AND PUSH
EAST/NORTHEAST. ORIENTATION/MAGNITUDE /30+KTS BY TONIGHT/ OF 0-3KM
SHEAR VECTOR IS FAVORABLE FOR SOME DURATION/ORGANIZATION TO LINE
SEGMENTS WHICH CAN ORIENT IN MORE N-S FASHION OR SOME VARIATION OF
THAT. NOT SURPRISINGLY...HRRR RUNS HAVE DEMONSTRATED SPORADIC SWATHS
OF DAMAGING WIND GUSTS > 50KTS ACROSS NRN IND POTENTIALLY
INVOLVING NWRN/WCNTL OH LATER THIS EVE /AFTER 10 PM OR SO/. REALLY
LIKE THE 5% WIND CONTOUR INTO WCNTL OHIO BASED ON THE HRRR/ARW WRF
SOLUTIONS SHOWING A WEAKENING ORGANIZED LINE COMING INTO OUR AREA
AROUND 10 PM...PERHAPS WITH SOME 40-50 MPH WINDS. THIS FITS
CURRENT MESOA WHICH HAS MINIMUM OF INSTBY IN WRN OH DUE TO MIXED
DWPTS IN THE 50S...SO LINE SHOULD WEAKEN CONSIDERABLY AS IT
CROSSES INTO OHIO...DESPITE BRINGING A MODEST INCREASE IN MOISTURE
VIA ADVECTION.
STRUGGLED A LOT WITH RAIN CHANCES...FEEL CONFIDENT ENOUGH FOR
LIKELY RAIN CHANCES WITH DYING LINE INTO ABOUT THE NWRN 1/2 OF OUR
FORECAST AREA...BUT ALL CAMS/PARAMETRIZED DATA SHOWING ACTIVITY
BECOMING MORE SCT WITH TIME AS NIGHT WEARS ON. SO RAIN CHANCES
OVERNIGHT RANGE FROM A LOW CONFIDENCE 20% IN FAR SOUTH/EAST UP TO
A 70% CHANCE OR SO IN WCNTL OH. ALL WILL DEPEND HOW QUICKLY THE
INCOMING LINE WEAKENS.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
FIRST HEIGHT FALL CENTER MENTIONED ABOVE PULLS EAST OF THE AREA
SUNDAY MORNING TAKING PRIMARY CONVERGENCE/PREFRONTAL TROUGH WITH
IT THROUGH THE MORNING. RESIDUAL SHOWERS/STORMS TO CROSS THE AREA
IN THE MORNING AND THEN SCT STORMS WILL BEGIN TO BUBBLE ALONG THIS
BOUNDARY LATE MORNING/EARLY AFTERNOON AND LIKELY IN OUR FAR
SOUTH/EAST OR JUST OUT OF OUR AREA. RATHER IMPRESSIVE/NARROW DRY
SLOT SHOULD WRAP IN LATE MORNING/EARLY AFTERNOON WITH SOME
SUNSHINE BEFORE STRONG CAA SETS IN DURING THE AFTERNOON WITH THE
PASSAGE OF SECONDARY FRONT. WITH SHALLOW INSTBY DEVELOPING...COULD
SEE SOME SCT SHRA DEVELOP WITH THIS FEATURE WHICH WAS ALREADY WELL
HANDLED BY PVS FORECASTER. THIS MOST LIKELY ACROSS OUR NORTH
CLOSER TO STRONG/COMPACT SHORTWAVE DIGGING ACROSS NRN OH. DON/T
EXPECT MUCH IF ANY THUNDER AFTER ABOUT 18Z...AS INSTBY BECOMES TOO
SHALLOW FOR CHARGE SEPARATION. WILL DEFINITELY A BE A CHANGEABLE
/AUTUMN-LIKE DAY DESPITE MAX TEMPS IN THE 70S. WINDS WILL BECOME
BREEZY/GUSTY IN THE AFTN AS THE COLD ADVECTION ARRIVES AND
CHANGEABLE SKY WITH THE DRY SLOT TO LOWER CLOUDS ALONG/BEHIND THE
SECONDARY SURFACE FRONT.
AS THIS ACTION ALL CLEARS THE CWA SUNDAY NIGHT AND STRONG HIGH
PRESSURE BUILDS IN...A VERY CHILLY NIGHT IN STORE WITH LOWS WELL
INTO THE 40S IN OUR INDIANA/WRN OHIO COUNTIES AS 925MB TEMPS DROP
TO +5C IN THIS AREA BY SUNRISE ON MONDAY. SHOULD SEE A SLOW DECREASE
IN LOW CLOUDS THROUGH THE NIGHT AND LESSENING WINDS AS
WELL...GIVEN THE DEGREE OF COLD AIR INBOUND...AM A LITTLE WORRIED
I AM CLEARING THE SKIES A LITTLE TOO QUICKLY AND STRATOCUMULUS MAY
BE MORE WIDESPREAD.
MONDAY BRINGS 1024MB SURFACE HIGH PRESSURE SPRAWLING INTO THE
GREAT LAKES AND CENTERED NEAR CHICAGO BY MONDAY EVENING. SHOULD BE
PLENTY OF SUNSHINE WITH DEWPTS IN THE 40S. CONTINUED WEAK CAA
SHOULD KEEP 925MB TEMPS IN THE +8 TO +10C RANGE WHICH PER CLIMO
STUDY SUGGESTS MAX TEMPS IN THE LOW TO MID 60S MOST
AREAS...DESPITE PLENTY OF SUN. MONDAY NIGHT WILL BE COLDEST OF THE
WEEK AND WOULD NOT BE SURPRISED TO SEE COLD PRONE/OUTLYING SITES
TOUCH THE MID TO UPPER 30S AGAIN LIKE DELAWARE/MARYSVILLE ETC DID
LAST WEEK. MAY EVEN BE A TOUCH COLDER THIS TIME AROUND. LOW TEMPS
THIS NIGHT MAY STILL BE A DEGREE OR TWO TOO WARM IN GOING
FORECAST...ESPECIALLY WITH SURFACE HIGH MOVING RIGHT OVERHEAD AT
12Z AND THE VERY DRY PROFILE /PWATS RUNNING 40% OF NORMAL/. AN
IDEAL RADIATIONAL COOLING SIGNAL BEING SEEN IN THE DATA.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
MID/UPPER LEVEL RIDGE WILL REMAIN IN PLACE ACROSS THE REGION
THROUGH THE END OF THE WEEK. THIS WILL RESULT IN DRY CONDITIONS AND
FAIRLY SEASONABLE TEMPERATURES THROUGH THE LONG TERM PERIOD. AS THE
AIRMASS SLOWLY MODIFIES...HIGH TEMPERATURES WILL GRADUALLY WARM EACH
DAY...FROM THE LOW TO MID 70S MID WEEK INTO THE UPPER 70S TO AROUND
80 DEGREES BY THE WEEKEND.
&&
.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
MVFR CEILINGS PERSIST AT CVG AND LUK...OTHERWISE TAF SITES HAVE
VFR. COLD FRONT WILL BE MOVING IN LATE TONIGHT/EARLY SUNDAY. THIS
WILL BRING SCATTERED SHOWERS AND POSSIBLY MORE MVFR CEILINGS. KEPT
THUNDER OUT FOR NOW SINCE FRONT WILL BE ARRIVING AT A DIURNALLY
UNFAVORABLE TIME. WINDS WILL GUST AROUND 20 KNOTS THIS AFTERNOON
OUT OF THE SOUTHWEST. GUSTS OVER 20 KNOTS ARE EXPECTED SUNDAY
AS DIRECTION SHIFTS TO WEST ALONG THE FRONT. CVG SHOULD SEE
CONTINUED GUSTY CONDITIONS AS WINDS BECOME NORTHWEST SUNDAY
AFTERNOON BEHIND THE FRONT.
OUTLOOK...MVFR CEILINGS POSSIBLE SUNDAY NIGHT.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...BINAU
NEAR TERM...BINAU
SHORT TERM...BINAU
LONG TERM...JGL
AVIATION...CONIGLIO
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
647 AM EDT SAT SEP 20 2014
.SYNOPSIS...
HIGH PRESSURE WILL MOVE OFF TO THE EAST TODAY AS A COLD FRONT
APPROACHES FROM THE NORTHWEST. THE COLD FRONT WILL MOVE ACROSS THE
AREA LATE TONIGHT AND SUNDAY. HIGH PRESSURE WILL THEN BECOME
REESTABLISHED FOR MUCH OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NEAR TERM MODELS...SUCH AS THE HRRR AND RAP...CONTINUE TO FORECAST
THE DEVELOPMENT OF LOWER LEVEL CLOUDS...4 K FT TO 6 KT ACROSS THE
SRN CWFA TOWARD MORNING. THIS DEVELOPMENT IS DUE TO WEAK
ISENTROPIC LIFT OCCURRING AROUND DEPARTING HIGH PRESSURE. THERE
MAY BE ENOUGH SHALLOW INSTABILITY IN THIS DECK TO WARRANT A LOW
CHANCE POP ALONG AND SOUTH OF THE OHIO RIVER THROUGH THE MORNING
HOURS.
OTHERWISE...WE SHOULD SEE PARTLY TO MOSTLY SUNNY SKIES TODAY OUT
AHEAD OF A COLD FRONT WHICH WILL MAKE IN ROADS TOWARD OUR REGION
TONIGHT. INCREASING SOUTHWEST FLOW BETWEEN THE DEPARTING HIGH AND
THE FRONT WILL BOOST TEMPERATURES INTO THE UPPER 70S TO THE LOWER
80S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
HAVE AGAIN USED A BLEND OF THE ECMWF/GFS...ALONG WITH CONVECTION
ALLOWING MODELS...TO HONE IN ON THE PROSPECTS OF PCPN TONIGHT INTO
SUNDAY NIGHT.
A SERIES OF S/WVS WILL DIG EAST/SOUTHEAST THROUGH THE GREAT LAKES
TONIGHT INTO SUNDAY NIGHT...WHICH WILL EVENTUALLY ESTABLISH A LONG
WAVE MID LEVEL TROUGH OVER ERN CANADA SOUTHWARD INTO THE ERN U.S.
BY MONDAY MORNING. THE FIRST WAVE...ALONG WITH PREFRONTAL
CONVERGENCE...IS EXPECTED TO RESULT IN SHOWERS/THUNDERSTORMS TO
OUR NORTHWEST LATE THIS AFTERNOON INTO EARLY THIS EVENING. MODELS
CONTINUE TO SUGGEST THAT AS THIS ACTIVITY PROPAGATES SOUTHEAST INTO
OUR AREA TONIGHT OUT AHEAD OF A COLD FRONT...IT WILL UNDERGO A
WEAKENING TREND. RAPIDLY DECREASING INSTABILITY...WEAKENING LOW
LEVEL FORCING...ALONG WITH WEAKENING UPPER LEVEL SUPPORT ARE THE
REASONS THAT THIS IS FORECAST TO OCCUR. AS A RESULT...HAVE PLACED
THE HIGHEST POPS TONIGHT OVER THE FAR NW...DECREASING THE THREAT
TO JUST 30 AND 40 PERCENT THROUGH THE REMAINDER OF THE REGION
TOWARD SUNDAY MORNING.
ON SUNDAY...ANOTHER EMBEDDED S/WV WILL APPROACH FROM THE NORTHWEST
WHILE THE COLD FRONT PUSHES EAST/SOUTHEAST THROUGH THE REGION.
WITH THE FASTER TIMING OF THE GFS/ECMWF...BELIEVE ANY
SHOWER/THUNDERSTORM REDEVELOPMENT SHOULD OCCUR JUST EAST/SOUTHEAST
OF THE AREA. IN THE WAKE OF THE FRONT...AND BEFORE THE ARRIVAL OF
THE NEXT S/WV...WE SHOULD SEE A POCKET OF DRY WEATHER ALONG WITH
PARTLY TO MOSTLY SUNNY SKIES. HIGHS ON SUNDAY WILL BE TRICKY AS
CAA WILL BE ONGOING THROUGH THE DAY. WILL FORECAST LOWER 70S
NORTHWEST TO THE UPPER 70S SOUTHERN/SOUTHEAST.
FOR SUNDAY NIGHT...AFOREMENTIONED S/WV WILL PASS THROUGH THE
REGION ALONG WITH A SFC TROF AXIS. THERE COULD BE ENOUGH
INSTABILITY WITH THIS FEATURE TO BRING A FEW SPOTTY SHOWERS TO THE
NRN ZONES SUNDAY EVENING. BUT AS TIME WEARS ON AND INSTABILITY
WANES...THE THREAT SHOULD RELEGATE ITSELF TO OUR NE TOWARD
CENTRAL/EASTERN LAKE ERIE. PARTLY CLOUD SKIES WILL UNDERGO A
CLEARING TREND...ESPECIALLY WEST OVERNIGHT. LOWS WILL DROP INTO
THE MID 40S NORTHWEST TO THE LOWER 50S SOUTHEAST.
FOR MONDAY INTO MONDAY NIGHT...MID LEVEL TROUGH WILL MOVE EAST AS
A MID LEVEL RIDGE BUILDS NORTHWARD INTO THE MIDDLE AND UPPER MS
RIVER VALLEY. AT THE SURFACE...A SPRAWLING AREA OF HIGH PRESSURE
WILL BE FOUND AS IT SETTLES RIGHT OVER THE OHIO VALLEY BY TUESDAY
MORNING. CLOUDS WILL CONTINUE TO DECREASE THROUGH THE PERIOD WITH
CLEAR SKIES EXPECTED BY MONDAY NIGHT. AFTER COOL TEMPERATURES
RANGING FROM THE LOWER 60S NORTH TO THE UPPER 60S SOUTH...OVERNIGHT
LOWS WILL DIP INTO THE UPPER 30S AND LOWER 40S BY TUESDAY MORNING.
ON TUESDAY...WITH THE HIGH REMAINING IN PLACE...SKIES WILL BE
SUNNY. HIGHS WILL WARM INTO THE UPPER 60S TO THE LOWER 70S.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
HIGH PRESSURE WILL KEEP DRY CONDITIONS ACROSS THE REGION THROUGH
THE LONG TERM. TEMPERATURES WILL SLOWLY WARM THROUGH THE LONG
TERM WITH HIGH TEMPERATURES BY FRIDAY EXPECTED TO BE IN THE MID TO
UPPER 70S.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
ALTHOUGH THE MAJORITY OF THE FORECAST PERIOD IS EXPECTED TO BE
VFR...THERE ARE A FEW ITEMS TO DISCUSS. ALTHOUGH ANY REMAINING
MVFR VISIBILITY RESTRICTIONS WILL BE SHORT-LIVED...AN INCREASE IN
MOISTURE FROM THE SOUTH WILL RESULT IN SCATTERED TO BROKEN CLOUDS
OVER THE REGION...GENERALLY IN THE 3500-6000 FOOT RANGE. SOUTHERLY
FLOW WILL SWITCH TO THE SOUTHWEST...WITH GUSTS IN THE 18-22 KNOT
RANGE BY EARLY AFTERNOON.
A COLD FRONT IS FORECAST TO APPROACH THE REGION FROM THE NORTHWEST
TONIGHT AND INTO SUNDAY MORNING. AHEAD OF THIS
FRONT...PRECIPITATION IS FORECAST TO MOVE INTO THE AREA LATE THIS
EVENING AND INTO THE EARLY MORNING HOURS. HOWEVER...THE EXTENT OF
PRECIPITATION WITH THIS FRONT IS NOT CERTAIN. THE PRECIPITATION
(WHICH COULD INCLUDE THUNDERSTORMS) SHOULD BE ON A WEAKENING TREND
AS IT MOVES THROUGH THE TAF SITES. A TEMPO -SHRA GROUP WAS
INCLUDED AT KDAY...BUT THE OTHER TAF SITES ARE NOT AS CERTAIN TO
RECEIVE RAIN. AS THE FRONT NEARS...CEILINGS ARE EXPECTED TO DROP
INTO THE MVFR RANGE.
OUTLOOK...A FEW SHOWERS...AND POSSIBLY A THUNDERSTORM...WILL BE
POSSIBLE DURING THE FIRST HALF OF SUNDAY. MVFR CEILINGS ARE ALSO
POSSIBLE ON SUNDAY MORNING.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HICKMAN
NEAR TERM...HICKMAN
SHORT TERM...HICKMAN
LONG TERM...NOVAK
AVIATION...HATZOS
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
417 AM EDT SAT SEP 20 2014
.SYNOPSIS...
HIGH PRESSURE WILL MOVE OFF TO THE EAST TODAY AS A COLD FRONT
APPROACHES FROM THE NORTHWEST. THE COLD FRONT WILL MOVE ACROSS THE
AREA LATE TONIGHT AND SUNDAY. HIGH PRESSURE WILL THEN BECOME
REESTABLISHED FOR MUCH OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NEAR TERM MODELS...SUCH AS THE HRRR AND RAP...CONTINUE TO FORECAST
THE DEVELOPMENT OF LOWER LEVEL CLOUDS...4 K FT TO 6 KT ACROSS THE
SRN CWFA TOWARD MORNING. THIS DEVELOPMENT IS DUE TO WEAK
ISENTROPIC LIFT OCCURRING AROUND DEPARTING HIGH PRESSURE. THERE
MAY BE ENOUGH SHALLOW INSTABILITY IN THIS DECK TO WARRANT A LOW
CHANCE POP ALONG AND SOUTH OF THE OHIO RIVER THROUGH THE MORNING
HOURS.
OTHERWISE...WE SHOULD SEE PARTLY TO MOSTLY SUNNY SKIES TODAY OUT
AHEAD OF A COLD FRONT WHICH WILL MAKE IN ROADS TOWARD OUR REGION
TONIGHT. INCREASING SOUTHWEST FLOW BETWEEN THE DEPARTING HIGH AND
THE FRONT WILL BOOST TEMPERATURES INTO THE UPPER 70S TO THE LOWER
80S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
HAVE AGAIN USED A BLEND OF THE ECMWF/GFS...ALONG WITH CONVECTION
ALLOWING MODELS...TO HONE IN ON THE PROSPECTS OF PCPN TONIGHT INTO
SUNDAY NIGHT.
A SERIES OF S/WVS WILL DIG EAST/SOUTHEAST THROUGH THE GREAT LAKES
TONIGHT INTO SUNDAY NIGHT...WHICH WILL EVENTUALLY ESTABLISH A LONG
WAVE MID LEVEL TROUGH OVER ERN CANADA SOUTHWARD INTO THE ERN U.S.
BY MONDAY MORNING. THE FIRST WAVE...ALONG WITH PREFRONTAL
CONVERGENCE...IS EXPECTED TO RESULT IN SHOWERS/THUNDERSTORMS TO
OUR NORTHWEST LATE THIS AFTERNOON INTO EARLY THIS EVENING. MODELS
CONTINUE TO SUGGEST THAT AS THIS ACTIVITY PROPAGATES SOUTHEAST INTO
OUR AREA TONIGHT OUT AHEAD OF A COLD FRONT...IT WILL UNDERGO A
WEAKENING TREND. RAPIDLY DECREASING INSTABILITY...WEAKENING LOW
LEVEL FORCING...ALONG WITH WEAKENING UPPER LEVEL SUPPORT ARE THE
REASONS THAT THIS IS FORECAST TO OCCUR. AS A RESULT...HAVE PLACED
THE HIGHEST POPS TONIGHT OVER THE FAR NW...DECREASING THE THREAT
TO JUST 30 AND 40 PERCENT THROUGH THE REMAINDER OF THE REGION
TOWARD SUNDAY MORNING.
ON SUNDAY...ANOTHER EMBEDDED S/WV WILL APPROACH FROM THE NORTHWEST
WHILE THE COLD FRONT PUSHES EAST/SOUTHEAST THROUGH THE REGION.
WITH THE FASTER TIMING OF THE GFS/ECMWF...BELIEVE ANY
SHOWER/THUNDERSTORM REDEVELOPMENT SHOULD OCCUR JUST EAST/SOUTHEAST
OF THE AREA. IN THE WAKE OF THE FRONT...AND BEFORE THE ARRIVAL OF
THE NEXT S/WV...WE SHOULD SEE A POCKET OF DRY WEATHER ALONG WITH
PARTLY TO MOSTLY SUNNY SKIES. HIGHS ON SUNDAY WILL BE TRICKY AS
CAA WILL BE ONGOING THROUGH THE DAY. WILL FORECAST LOWER 70S
NORTHWEST TO THE UPPER 70S SOUTHERN/SOUTHEAST.
FOR SUNDAY NIGHT...AFOREMENTIONED S/WV WILL PASS THROUGH THE
REGION ALONG WITH A SFC TROF AXIS. THERE COULD BE ENOUGH
INSTABILITY WITH THIS FEATURE TO BRING A FEW SPOTTY SHOWERS TO THE
NRN ZONES SUNDAY EVENING. BUT AS TIME WEARS ON AND INSTABILITY
WANES...THE THREAT SHOULD RELEGATE ITSELF TO OUR NE TOWARD
CENTRAL/EASTERN LAKE ERIE. PARTLY CLOUD SKIES WILL UNDERGO A
CLEARING TREND...ESPECIALLY WEST OVERNIGHT. LOWS WILL DROP INTO
THE MID 40S NORTHWEST TO THE LOWER 50S SOUTHEAST.
FOR MONDAY INTO MONDAY NIGHT...MID LEVEL TROUGH WILL MOVE EAST AS
A MID LEVEL RIDGE BUILDS NORTHWARD INTO THE MIDDLE AND UPPER MS
RIVER VALLEY. AT THE SURFACE...A SPRAWLING AREA OF HIGH PRESSURE
WILL BE FOUND AS IT SETTLES RIGHT OVER THE OHIO VALLEY BY TUESDAY
MORNING. CLOUDS WILL CONTINUE TO DECREASE THROUGH THE PERIOD WITH
CLEAR SKIES EXPECTED BY MONDAY NIGHT. AFTER COOL TEMPERATURES
RANGING FROM THE LOWER 60S NORTH TO THE UPPER 60S SOUTH...OVERNIGHT
LOWS WILL DIP INTO THE UPPER 30S AND LOWER 40S BY TUESDAY MORNING.
ON TUESDAY...WITH THE HIGH REMAINING IN PLACE...SKIES WILL BE
SUNNY. HIGHS WILL WARM INTO THE UPPER 60S TO THE LOWER 70S.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
HIGH PRESSURE WILL KEEP DRY CONDITIONS ACROSS THE REGION THROUGH
THE LONG TERM. TEMPERATURES WILL SLOWLY WARM THROUGH THE LONG
TERM WITH HIGH TEMPERATURES BY FRIDAY EXPECTED TO BE IN THE MID TO
UPPER 70S.
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS ARE GENERALLY EXPECTED...BUT WITH A FEW
COMPLICATIONS IN THE FORECAST TO DISCUSS. TRANQUIL CONDITIONS TO
BEGIN THE OVERNIGHT PERIOD WILL GIVE WAY TO INCREASING SOUTHERLY
FLOW BY MORNING...TURNING SOUTHWESTERLY AND GUSTY (UP TO 20 KNOTS)
BY EARLY AFTERNOON. AN INCREASE IN CLOUDS IS EXPECTED GOING INTO
THE DAY...GENERALLY IN THE 4000-6000 FOOT RANGE. MVFR FOG AT KLUK
WILL LIKELY DISSIPATE OVER THE NEXT FEW HOURS...AS WINDS BEGIN TO
INCREASE.
A COLD FRONT WILL APPROACH THE REGION ON SATURDAY NIGHT AND INTO
EARLY SUNDAY MORNING. THE EXTENT OF PRECIPITATION WITH THIS FRONT
IS NOT CERTAIN...BUT IT LOOKS LIKE THE TIMING WILL BRING
A CHANCE OF PRE-FRONTAL PRECIPITATION TO THE TAF SITES BY 05Z-08Z.
OUTLOOK...THUNDERSTORMS ARE POSSIBLE FROM LATE SATURDAY NIGHT
THROUGH SUNDAY AFTERNOON.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HICKMAN
NEAR TERM...HICKMAN
SHORT TERM...HICKMAN
LONG TERM...NOVAK
AVIATION...HATZOS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1145 AM CDT SAT SEP 20 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 250 AM CDT SAT SEP 20 2014
MAIN CONCERNS ARE ON EXITING MORNING CONVECTION AND THE RETURN FOR
MORE CONVECTION TONIGHT.
CURRENTLY AS OF 07Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED AN UPPER LOW JUST OFF THE CALIFORNIA COAST...RIDGING OVER THE
WESTERN THIRD OF THE U.S. INTO BRITISH COLUMBIA...AND TROUGHING OVER
CENTRAL CANADA INTO THE NORTHERN PLAINS/UPPER MIDWEST. A COUPLE OF
SHORTWAVES TRAVERSING THROUGH THIS TROUGH IN SOUTH DAKOTA AND MN...
COMBINED WITH A SURFACE TO 850MB COLD FRONT THAT STRETCHED FROM
DULUTH TO SIOUX CITY IA...HAVE AIDED IN MAINTAINING A BAND OF
SHOWERS AND THUNDERSTORMS. THIS BAND EXTENDS FROM WEST CENTRAL IA
THROUGH THE FORECAST AREA. MUCH OF THE ACTIVITY HAS BEEN ELEVATED IN
NATURE DUE TO CAPPING PRESENT OF BL PARCELS. PLENTY OF INSTABILITY
FOR THE CONVECTION WITH CAPE VALUES LIFTED FROM 1 KM BETWEEN 1000-
2000 J/KG. IN THE WAKE OF THE CONVECTION...THERE HAS BEEN A NARROW
AREA OF LOW STRATUS DEVELOPING...BEFORE CLOUDS CLEAR OUT OVER
CENTRAL MN. AIRMASS BEHIND THE COLD FRONT WAS NOT MUCH COLDER THAN
AHEAD...WITH 925MB TEMPS HOVERING BETWEEN 20-24C. HOWEVER...
PRECIPITABLE WATER DROPS SIGNIFICANTLY FROM 1.5-1.75 INCHES TO 1-
1.25 INCHES. UPSTREAM A MORE SIGNIFICANT COLD FRONT EXISTS OVER
NORTHERN NORTH DAKOTA AND NORTHWEST MN WHERE 925MB TEMPS DROP TO 12-
14C.
THE COLLECTION OF SHORTWAVES ACROSS SOUTH DAKOTA AND MN ARE PROGGED
TO CROSS THE FORECAST AREA THIS MORNING...PUSHING THE SURFACE-850MB
COLD FRONT THROUGH MUCH IF NOT ALL OF THE AREA BY 18Z. ANTICIPATING
MUCH OF THE CURRENT CONVECTION AHEAD OF THESE FEATURES TO MARCH
SOUTHEASTWARD OUT OF THE FORECAST AREA BY 13Z PER HIGH RESOLUTION
MODEL CONSENSUS. STILL CARRIED SOME LOW PRECIPITATION CHANCES OVER
THE SOUTHEAST HALF IN THE WAKE OF THE CURRENT ACTIVITY IN THE EVENT
ADDITIONAL SHOWERS/STORMS FORM AS THE SHORTWAVES MOVE IN.
OTHERWISE...SUBSIDENCE AND DRYING OF PRECIPITABLE WATER SHOULD ALLOW
SKIES TO CLEAR AFTER A BRIEF PERIOD OF MORNING STRATUS. THE SUNSHINE
COMBINED WITH 925MB TEMPS OF 18-20C FOR MUCH OF TODAY SHOULD ALLOW
FOR HIGHS TO TOP OUT IN THE 70S IN MOST LOCATIONS...WITH SOME LOW
80S IN VALLEYS.
SHORTLY AFTER 00Z THIS EVENING...ANOTHER LINE OF SHOWERS AND
EMBEDDED THUNDERSTORMS LOOKS LIKELY TO MOVE ACROSS THE REGION...
ESPECIALLY ALONG AND NORTH OF I-90. THIS LINE OF CONVECTION WILL BE
FORCED BY A POTENT SHORTWAVE OVER CENTRAL ALBERTA DROPPING THROUGH
THE UPPER MIDWEST TROUGHING. THE SHORTWAVE SHOULD ALSO HAVE A NARROW
CORRIDOR OF MOISTURE TO WORK WITH AS PRECIPITABLE WATER JUMPS UP TO
1-1.3 INCHES. INSTABILITY WISE...ITS FAIRLY MEAGER WITH VALUES OF
100-500 J/KG...MOSTLY IN THE EVENING DUE TO LOSS OF DAYTIME HEATING
COOLING THE BOUNDARY LAYER. ANTICIPATING MORE THUNDERSTORM ACTIVITY
SHOULD OCCUR TODAY UPSTREAM OVER NORTH DAKOTA INTO CENTRAL MN WHERE
THE JUXTAPOSITION OF HIGHER DIURNALLY BASED INSTABILITY INTERSECTS
THE SHORTWAVE. SHEAR PROFILES WOULD CERTAINLY SUPPORT BOTH A
DAMAGING WIND AND LARGE HAIL THREAT WITH CONVECTION...HOWEVER...THE
MEAGER INSTABILITY BY THE TIME THE CONVECTION MOVES INTO THE
FORECAST AREA SHOULD HELP MITIGATE SEVERE POTENTIAL. MAY STILL SEE
SOME STRONGER WIND GUSTS...THOUGH. HAVE RAISED PRECIPITATION CHANCES
UP FOR THE EVENING HOURS GIVEN VERY GOOD MODEL CONSENSUS FOR THIS
CONVECTION. KEPT SOME PRECIPITATION CHANCES GOING OVERNIGHT TOO
ALONG AND NORTH OF I-94 WHERE A FRONTOGENESIS BAND LOOKS TO SETUP ON
THE NORTH SIDE OF THE SHORTWAVE. LOOK FOR COOLER TEMPERATURES
TONIGHT AS COLDER AIR RUSHES IN BEHIND THE LINE OF CONVECTION. IN
FACT...925MB TEMPS COOL AS MUCH AS 10C ON A BRISK 30-40 KT 925MB
NORTHWEST WIND.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 250 AM CDT SAT SEP 20 2014
MAIN CONCERNS ARE ON PRECIPITATION POTENTIAL FOR SUNDAY...FOLLOWED
BY TEMPERATURES AND VALLEY FOG POTENTIAL SUNDAY NIGHT AND BEYOND.
ANOTHER POTENT SHORTWAVE LOOKS TO FOLLOW QUICKLY ON THE HEELS OF THE
ONE MOVING THROUGH THE FORECAST AREA TONIGHT. THIS SHORTWAVE...
CURRENTLY IN NORTHERN SASKATCHEWAN...IS PROGGED TO DROP SOUTH
THROUGH THE FORECAST AREA SUNDAY MORNING. THIS SHORTWAVE WILL HELP
TO PULL THE FRONTOGENESIS BAND AND ASSOCIATED SURFACE COLD FRONT
SOUTHWARD THROUGH THE FORECAST AREA DURING THE MORNING HOURS.
APPEARS THE BULK OF THE RAIN/SHOWER ACTIVITY WITH THE BAND WILL BE
CONFINED TO WISCONSIN...BUT SOME MAY EVEN CREEP ACROSS THE MS RIVER
AS SUGGESTED BY THE 20.00Z ECMWF/CANADIAN. HAVE RAISED PRECIPITATION
CHANCES UPWARDS AND FURTHER INCREASES MAY BE NECESSARY. OVERALL
AMOUNTS LOOK TO BE FAIRLY LIGHT...THOUGH. THIS FRONTAL BOUNDARY
DROPPING SOUTH...925MB TEMPS ONLY TOPPING OUT FROM 10-12C AT 00Z
MONDAY...A BREEZY NORTH WIND AND A DECENT AMOUNT OF SUN NOT
OCCURRING UNTIL LATE IN THE DAY WILL YIELD MUCH COOLER CONDITIONS
COMPARED TO TODAY.
MODELS REMAIN IN GOOD AGREEMENT IN BUILDING HIGH PRESSURE INTO THE
FORECAST AREA FOR SUNDAY NIGHT THROUGH TUESDAY. THIS IS IN RESPONSE
TO THE UPPER RIDGE OVER THE WESTERN THIRD OF THE U.S. MARCHING EAST
INTO MN AND IA BY 12Z TUE. THE MAIN CENTER OF THE HIGH LOOKS TO
TRACK JUST SOUTH OF THE AREA...BUT THE GRADIENT RELAXES ENOUGH TO
ALLOW FOR DECOUPLING BOTH NIGHTS. SOME CLOUDS COULD DRIFT ACROSS
BOTH NIGHTS...BUT IT APPEARS ENOUGH PERIOD OF CLEAR SKIES SHOULD
EXIST FOR VALLEY FOG TO FORM...ESPECIALLY IN THE TRIBUTARIES. SUNDAY
NIGHT WILL BE THE COOLER OF THE TWO NIGHTS DUE TO AIRMASS
MODIFICATION TAKING PLACE ON MONDAY. THE TYPICAL COLD SPOTS IN
CENTRAL WI COULD DIP INTO THE MID/UPPER 30S SUNDAY NIGHT. 925MB
TEMPS OF 12-14C ON MONDAY WITH MORE SUN WILL ALLOW HIGHS TO TOP OUT
IN THE 60S TO LOW 70S...WARMEST IN VALLEYS. THESE 925MB TEMPS CLIMB
ANOTHER 1-2C ON TUESDAY...RESULTING IN A SIMILAR BUMP UP IN HIGHS.
IN GENERAL THE WEATHER REMAINS FAIRLY QUIET FROM TUESDAY NIGHT RIGHT
INTO NEXT WEEKEND...THANKS TO SIGNIFICANT UPPER RIDGING BUILDING UP
OVER THE EASTERN TWO THIRDS OF THE U.S.. IN FACT...MOST LONG RANGE
GUIDANCE IS SUGGESTING A 590 DAM 500MB HIGH TO FORM OVER MICHIGAN BY
00Z SATURDAY...WHICH WOULD BE ABOUT 2 STANDARD DEVIATIONS ABOVE
NORMAL. THIS IS ALL A RESULT OF A VERY DEEP TROUGH DEVELOPING ALONG
THE WEST COAST OF THE U.S....SOMETHING THAT HASNT BEEN SEEN FOR
QUITE SOME TIME. THE ONLY REAL ISSUE TO WORRY ABOUT IS THE CURRENT
UPPER LOW OFF THE CALIFORNIA COAST...WHICH MODELS TRY TO BRING
THROUGH THE FORECAST AREA IN A WEAKENING STATE CENTERED AROUND
WEDNESDAY. HAVE MAINTAINED SOME LOW PRECIPITATION CHANCES ASSOCIATED
WITH THIS FEATURE. DESPITE THE RISING 500MB HEIGHTS...IT TAKES
AWHILE FOR A SIMILAR RESPONSE TO 850MB TEMPS...PARTIALLY DUE TO THAT
UPPER LOW LIFTING THROUGH. THUS...TEMPERATURES HOLD NEAR SEASONABLE
NORMALS UNTIL THE END OF THE WEEK. FRIDAY...SATURDAY AND SUNDAY ALL
LOOK ABOVE NORMAL WITH HIGHS POSSIBLY APPROACHING 80.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1145 AM CDT SAT SEP 20 2014
SFC FRONT SLIDING ACROSS THE REGION...WITH SATELLITE IMAGERY
POINTING TO SKC SKIES POST FRONT. EXPECTING VFR CONDITIONS THROUGH
THE AFTERNOON INTO THE EARLY EVENING.
AN UPPER LEVEL SHORTWAVE TROUGH WILL DRIVE SOUTHEAST ACROSS THE
NORTHERN PLAINS AND THEN THROUGH THE UPPER MISSISSIPPI RIVER VALLEY
TONIGHT. A COLD FRONT AT THE SFC WILL ACCOMPANY THE SHORTWAVE...AND
HELP FIRE A LINE OF SHOWERS/ISOLATED THUNDERSTORMS AS IT MOVES
THROUGH. COULD SEE SOME HIGHER GUSTS AROUND THE STRONGER STORMS -
WITH AN ISOLATED SEVERE THREAT EARLY IN THE EVENING.
UPSTREAM OBS WITH THE SHORTWAVE POINT TO AN AREA OF MVFR CIGS IN THE
2-2.5 KFT RANGE. MODEL RH FIELDS AND BUFKIT SOUNDINGS FAVOR THIS
TOO...ESPECIALLY ALONG AND EAST OF THE MISSISSIPPI RIVER. MOST OF
THIS APPEARS POST THE APPROX 3 HOUR WINDOW WHEN A -SHRA/TS THREAT IS
HIGHLIGHTED. SPEAKING OF WHICH...WITH INSTABILITY MINIMAL AT
BEST...WILL KEEP MENTION TO -SHRA RATHER THAN -TSRA. DYNAMICS DO
APPEAR STRONG ENOUGH FOR SOME ISOLD THUNDER...BUT NOT CONFIDENT
ENOUGH TO INCLUDE IN TAFS AT THIS TIME.
FRONT LIKELY LINGERS ACROSS THE REGION FOR THE BETTER PART OF
SUNDAY...BEFORE HIGH PRESSURE AND SUBSIDENCE WORKS IN BY THE
EVENING. KLSE COULD BE UNDER MVFR CLOUDS FOR THE BETTER PART OF THE
MORNING...POTENTIALLY LINGERING THROUGH THE AFTERNOON.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...RIECK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
659 AM CDT SAT SEP 20 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 250 AM CDT SAT SEP 20 2014
MAIN CONCERNS ARE ON EXITING MORNING CONVECTION AND THE RETURN FOR
MORE CONVECTION TONIGHT.
CURRENTLY AS OF 07Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED AN UPPER LOW JUST OFF THE CALIFORNIA COAST...RIDGING OVER THE
WESTERN THIRD OF THE U.S. INTO BRITISH COLUMBIA...AND TROUGHING OVER
CENTRAL CANADA INTO THE NORTHERN PLAINS/UPPER MIDWEST. A COUPLE OF
SHORTWAVES TRAVERSING THROUGH THIS TROUGH IN SOUTH DAKOTA AND MN...
COMBINED WITH A SURFACE TO 850MB COLD FRONT THAT STRETCHED FROM
DULUTH TO SIOUX CITY IA...HAVE AIDED IN MAINTAINING A BAND OF
SHOWERS AND THUNDERSTORMS. THIS BAND EXTENDS FROM WEST CENTRAL IA
THROUGH THE FORECAST AREA. MUCH OF THE ACTIVITY HAS BEEN ELEVATED IN
NATURE DUE TO CAPPING PRESENT OF BL PARCELS. PLENTY OF INSTABILITY
FOR THE CONVECTION WITH CAPE VALUES LIFTED FROM 1 KM BETWEEN 1000-
2000 J/KG. IN THE WAKE OF THE CONVECTION...THERE HAS BEEN A NARROW
AREA OF LOW STRATUS DEVELOPING...BEFORE CLOUDS CLEAR OUT OVER
CENTRAL MN. AIRMASS BEHIND THE COLD FRONT WAS NOT MUCH COLDER THAN
AHEAD...WITH 925MB TEMPS HOVERING BETWEEN 20-24C. HOWEVER...
PRECIPITABLE WATER DROPS SIGNIFICANTLY FROM 1.5-1.75 INCHES TO 1-
1.25 INCHES. UPSTREAM A MORE SIGNIFICANT COLD FRONT EXISTS OVER
NORTHERN NORTH DAKOTA AND NORTHWEST MN WHERE 925MB TEMPS DROP TO 12-
14C.
THE COLLECTION OF SHORTWAVES ACROSS SOUTH DAKOTA AND MN ARE PROGGED
TO CROSS THE FORECAST AREA THIS MORNING...PUSHING THE SURFACE-850MB
COLD FRONT THROUGH MUCH IF NOT ALL OF THE AREA BY 18Z. ANTICIPATING
MUCH OF THE CURRENT CONVECTION AHEAD OF THESE FEATURES TO MARCH
SOUTHEASTWARD OUT OF THE FORECAST AREA BY 13Z PER HIGH RESOLUTION
MODEL CONSENSUS. STILL CARRIED SOME LOW PRECIPITATION CHANCES OVER
THE SOUTHEAST HALF IN THE WAKE OF THE CURRENT ACTIVITY IN THE EVENT
ADDITIONAL SHOWERS/STORMS FORM AS THE SHORTWAVES MOVE IN.
OTHERWISE...SUBSIDENCE AND DRYING OF PRECIPITABLE WATER SHOULD ALLOW
SKIES TO CLEAR AFTER A BRIEF PERIOD OF MORNING STRATUS. THE SUNSHINE
COMBINED WITH 925MB TEMPS OF 18-20C FOR MUCH OF TODAY SHOULD ALLOW
FOR HIGHS TO TOP OUT IN THE 70S IN MOST LOCATIONS...WITH SOME LOW
80S IN VALLEYS.
SHORTLY AFTER 00Z THIS EVENING...ANOTHER LINE OF SHOWERS AND
EMBEDDED THUNDERSTORMS LOOKS LIKELY TO MOVE ACROSS THE REGION...
ESPECIALLY ALONG AND NORTH OF I-90. THIS LINE OF CONVECTION WILL BE
FORCED BY A POTENT SHORTWAVE OVER CENTRAL ALBERTA DROPPING THROUGH
THE UPPER MIDWEST TROUGHING. THE SHORTWAVE SHOULD ALSO HAVE A NARROW
CORRIDOR OF MOISTURE TO WORK WITH AS PRECIPITABLE WATER JUMPS UP TO
1-1.3 INCHES. INSTABILITY WISE...ITS FAIRLY MEAGER WITH VALUES OF
100-500 J/KG...MOSTLY IN THE EVENING DUE TO LOSS OF DAYTIME HEATING
COOLING THE BOUNDARY LAYER. ANTICIPATING MORE THUNDERSTORM ACTIVITY
SHOULD OCCUR TODAY UPSTREAM OVER NORTH DAKOTA INTO CENTRAL MN WHERE
THE JUXTAPOSITION OF HIGHER DIURNALLY BASED INSTABILITY INTERSECTS
THE SHORTWAVE. SHEAR PROFILES WOULD CERTAINLY SUPPORT BOTH A
DAMAGING WIND AND LARGE HAIL THREAT WITH CONVECTION...HOWEVER...THE
MEAGER INSTABILITY BY THE TIME THE CONVECTION MOVES INTO THE
FORECAST AREA SHOULD HELP MITIGATE SEVERE POTENTIAL. MAY STILL SEE
SOME STRONGER WIND GUSTS...THOUGH. HAVE RAISED PRECIPITATION CHANCES
UP FOR THE EVENING HOURS GIVEN VERY GOOD MODEL CONSENSUS FOR THIS
CONVECTION. KEPT SOME PRECIPITATION CHANCES GOING OVERNIGHT TOO
ALONG AND NORTH OF I-94 WHERE A FRONTOGENESIS BAND LOOKS TO SETUP ON
THE NORTH SIDE OF THE SHORTWAVE. LOOK FOR COOLER TEMPERATURES
TONIGHT AS COLDER AIR RUSHES IN BEHIND THE LINE OF CONVECTION. IN
FACT...925MB TEMPS COOL AS MUCH AS 10C ON A BRISK 30-40 KT 925MB
NORTHWEST WIND.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 250 AM CDT SAT SEP 20 2014
MAIN CONCERNS ARE ON PRECIPITATION POTENTIAL FOR SUNDAY...FOLLOWED
BY TEMPERATURES AND VALLEY FOG POTENTIAL SUNDAY NIGHT AND BEYOND.
ANOTHER POTENT SHORTWAVE LOOKS TO FOLLOW QUICKLY ON THE HEELS OF THE
ONE MOVING THROUGH THE FORECAST AREA TONIGHT. THIS SHORTWAVE...
CURRENTLY IN NORTHERN SASKATCHEWAN...IS PROGGED TO DROP SOUTH
THROUGH THE FORECAST AREA SUNDAY MORNING. THIS SHORTWAVE WILL HELP
TO PULL THE FRONTOGENESIS BAND AND ASSOCIATED SURFACE COLD FRONT
SOUTHWARD THROUGH THE FORECAST AREA DURING THE MORNING HOURS.
APPEARS THE BULK OF THE RAIN/SHOWER ACTIVITY WITH THE BAND WILL BE
CONFINED TO WISCONSIN...BUT SOME MAY EVEN CREEP ACROSS THE MS RIVER
AS SUGGESTED BY THE 20.00Z ECMWF/CANADIAN. HAVE RAISED PRECIPITATION
CHANCES UPWARDS AND FURTHER INCREASES MAY BE NECESSARY. OVERALL
AMOUNTS LOOK TO BE FAIRLY LIGHT...THOUGH. THIS FRONTAL BOUNDARY
DROPPING SOUTH...925MB TEMPS ONLY TOPPING OUT FROM 10-12C AT 00Z
MONDAY...A BREEZY NORTH WIND AND A DECENT AMOUNT OF SUN NOT
OCCURRING UNTIL LATE IN THE DAY WILL YIELD MUCH COOLER CONDITIONS
COMPARED TO TODAY.
MODELS REMAIN IN GOOD AGREEMENT IN BUILDING HIGH PRESSURE INTO THE
FORECAST AREA FOR SUNDAY NIGHT THROUGH TUESDAY. THIS IS IN RESPONSE
TO THE UPPER RIDGE OVER THE WESTERN THIRD OF THE U.S. MARCHING EAST
INTO MN AND IA BY 12Z TUE. THE MAIN CENTER OF THE HIGH LOOKS TO
TRACK JUST SOUTH OF THE AREA...BUT THE GRADIENT RELAXES ENOUGH TO
ALLOW FOR DECOUPLING BOTH NIGHTS. SOME CLOUDS COULD DRIFT ACROSS
BOTH NIGHTS...BUT IT APPEARS ENOUGH PERIOD OF CLEAR SKIES SHOULD
EXIST FOR VALLEY FOG TO FORM...ESPECIALLY IN THE TRIBUTARIES. SUNDAY
NIGHT WILL BE THE COOLER OF THE TWO NIGHTS DUE TO AIRMASS
MODIFICATION TAKING PLACE ON MONDAY. THE TYPICAL COLD SPOTS IN
CENTRAL WI COULD DIP INTO THE MID/UPPER 30S SUNDAY NIGHT. 925MB
TEMPS OF 12-14C ON MONDAY WITH MORE SUN WILL ALLOW HIGHS TO TOP OUT
IN THE 60S TO LOW 70S...WARMEST IN VALLEYS. THESE 925MB TEMPS CLIMB
ANOTHER 1-2C ON TUESDAY...RESULTING IN A SIMILAR BUMP UP IN HIGHS.
IN GENERAL THE WEATHER REMAINS FAIRLY QUIET FROM TUESDAY NIGHT RIGHT
INTO NEXT WEEKEND...THANKS TO SIGNIFICANT UPPER RIDGING BUILDING UP
OVER THE EASTERN TWO THIRDS OF THE U.S.. IN FACT...MOST LONG RANGE
GUIDANCE IS SUGGESTING A 590 DAM 500MB HIGH TO FORM OVER MICHIGAN BY
00Z SATURDAY...WHICH WOULD BE ABOUT 2 STANDARD DEVIATIONS ABOVE
NORMAL. THIS IS ALL A RESULT OF A VERY DEEP TROUGH DEVELOPING ALONG
THE WEST COAST OF THE U.S....SOMETHING THAT HASNT BEEN SEEN FOR
QUITE SOME TIME. THE ONLY REAL ISSUE TO WORRY ABOUT IS THE CURRENT
UPPER LOW OFF THE CALIFORNIA COAST...WHICH MODELS TRY TO BRING
THROUGH THE FORECAST AREA IN A WEAKENING STATE CENTERED AROUND
WEDNESDAY. HAVE MAINTAINED SOME LOW PRECIPITATION CHANCES ASSOCIATED
WITH THIS FEATURE. DESPITE THE RISING 500MB HEIGHTS...IT TAKES
AWHILE FOR A SIMILAR RESPONSE TO 850MB TEMPS...PARTIALLY DUE TO THAT
UPPER LOW LIFTING THROUGH. THUS...TEMPERATURES HOLD NEAR SEASONABLE
NORMALS UNTIL THE END OF THE WEEK. FRIDAY...SATURDAY AND SUNDAY ALL
LOOK ABOVE NORMAL WITH HIGHS POSSIBLY APPROACHING 80.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 658 AM CDT SAT SEP 20 2014
SCATTERED SHOWERS AHEAD OF A COLD FRONT WILL AFFECT KRST THROUGH
20.16Z. THE MESO MODELS SUGGEST THAT THESE SHOWERS WILL NOT MAKE
IT INTO KLSE. HOWEVER WITH WEAK 700 MB MOISTURE TRANSPORT INTO THE
AREA BETWEEN 20.15Z AND 20.18Z...MAY HAVE TO RECONSIDER ADDING
THEM TO THE TAF LATER THIS MORNING. AFTER THE PASSAGE OF THIS
FRONT...IT WILL REMAIN DRY WITH VFR CEILINGS AND VISIBILITIES
THROUGH THIS AFTERNOON.
ANOTHER COLD FRONT WILL MOVE THROUGH THE TAF SITES THIS EVENING.
IT WILL MOVE THROUGH KRST BETWEEN 21.01Z AND 21.03Z...AND KLSE
BETWEEN 21.02Z AND 21.04Z. CEILINGS WILL DROP TO 5K FEET DURING
THIS TIME PERIOD. VISIBILITIES MAY BECOME BRIEFLY MVFR IN SHOWERS.
FOR LATE TONIGHT...THE MODEL SUGGEST THAT A MVFR STRATUS DECK MAY
DEVELOP. HOWEVER WITH DRY AIR LOCATED ACROSS REGION...A BIT
CONCERNED THAT THE MODELS MAY BE OVER DOING THIS...SO OPTED NOT
PUTTING THESE CLOUDS IN THE TAFS AT THIS TIME.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
250 AM CDT SAT SEP 20 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 250 AM CDT SAT SEP 20 2014
MAIN CONCERNS ARE ON EXITING MORNING CONVECTION AND THE RETURN FOR
MORE CONVECTION TONIGHT.
CURRENTLY AS OF 07Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED AN UPPER LOW JUST OFF THE CALIFORNIA COAST...RIDGING OVER THE
WESTERN THIRD OF THE U.S. INTO BRITISH COLUMBIA...AND TROUGHING OVER
CENTRAL CANADA INTO THE NORTHERN PLAINS/UPPER MIDWEST. A COUPLE OF
SHORTWAVES TRAVERSING THROUGH THIS TROUGH IN SOUTH DAKOTA AND MN...
COMBINED WITH A SURFACE TO 850MB COLD FRONT THAT STRETCHED FROM
DULUTH TO SIOUX CITY IA...HAVE AIDED IN MAINTAINING A BAND OF
SHOWERS AND THUNDERSTORMS. THIS BAND EXTENDS FROM WEST CENTRAL IA
THROUGH THE FORECAST AREA. MUCH OF THE ACTIVITY HAS BEEN ELEVATED IN
NATURE DUE TO CAPPING PRESENT OF BL PARCELS. PLENTY OF INSTABILITY
FOR THE CONVECTION WITH CAPE VALUES LIFTED FROM 1 KM BETWEEN 1000-
2000 J/KG. IN THE WAKE OF THE CONVECTION...THERE HAS BEEN A NARROW
AREA OF LOW STRATUS DEVELOPING...BEFORE CLOUDS CLEAR OUT OVER
CENTRAL MN. AIRMASS BEHIND THE COLD FRONT WAS NOT MUCH COLDER THAN
AHEAD...WITH 925MB TEMPS HOVERING BETWEEN 20-24C. HOWEVER...
PRECIPITABLE WATER DROPS SIGNIFICANTLY FROM 1.5-1.75 INCHES TO 1-
1.25 INCHES. UPSTREAM A MORE SIGNIFICANT COLD FRONT EXISTS OVER
NORTHERN NORTH DAKOTA AND NORTHWEST MN WHERE 925MB TEMPS DROP TO 12-
14C.
THE COLLECTION OF SHORTWAVES ACROSS SOUTH DAKOTA AND MN ARE PROGGED
TO CROSS THE FORECAST AREA THIS MORNING...PUSHING THE SURFACE-850MB
COLD FRONT THROUGH MUCH IF NOT ALL OF THE AREA BY 18Z. ANTICIPATING
MUCH OF THE CURRENT CONVECTION AHEAD OF THESE FEATURES TO MARCH
SOUTHEASTWARD OUT OF THE FORECAST AREA BY 13Z PER HIGH RESOLUTION
MODEL CONSENSUS. STILL CARRIED SOME LOW PRECIPITATION CHANCES OVER
THE SOUTHEAST HALF IN THE WAKE OF THE CURRENT ACTIVITY IN THE EVENT
ADDITIONAL SHOWERS/STORMS FORM AS THE SHORTWAVES MOVE IN.
OTHERWISE...SUBSIDENCE AND DRYING OF PRECIPITABLE WATER SHOULD ALLOW
SKIES TO CLEAR AFTER A BRIEF PERIOD OF MORNING STRATUS. THE SUNSHINE
COMBINED WITH 925MB TEMPS OF 18-20C FOR MUCH OF TODAY SHOULD ALLOW
FOR HIGHS TO TOP OUT IN THE 70S IN MOST LOCATIONS...WITH SOME LOW
80S IN VALLEYS.
SHORTLY AFTER 00Z THIS EVENING...ANOTHER LINE OF SHOWERS AND
EMBEDDED THUNDERSTORMS LOOKS LIKELY TO MOVE ACROSS THE REGION...
ESPECIALLY ALONG AND NORTH OF I-90. THIS LINE OF CONVECTION WILL BE
FORCED BY A POTENT SHORTWAVE OVER CENTRAL ALBERTA DROPPING THROUGH
THE UPPER MIDWEST TROUGHING. THE SHORTWAVE SHOULD ALSO HAVE A NARROW
CORRIDOR OF MOISTURE TO WORK WITH AS PRECIPITABLE WATER JUMPS UP TO
1-1.3 INCHES. INSTABILITY WISE...ITS FAIRLY MEAGER WITH VALUES OF
100-500 J/KG...MOSTLY IN THE EVENING DUE TO LOSS OF DAYTIME HEATING
COOLING THE BOUNDARY LAYER. ANTICIPATING MORE THUNDERSTORM ACTIVITY
SHOULD OCCUR TODAY UPSTREAM OVER NORTH DAKOTA INTO CENTRAL MN WHERE
THE JUXTAPOSITION OF HIGHER DIURNALLY BASED INSTABILITY INTERSECTS
THE SHORTWAVE. SHEAR PROFILES WOULD CERTAINLY SUPPORT BOTH A
DAMAGING WIND AND LARGE HAIL THREAT WITH CONVECTION...HOWEVER...THE
MEAGER INSTABILITY BY THE TIME THE CONVECTION MOVES INTO THE
FORECAST AREA SHOULD HELP MITIGATE SEVERE POTENTIAL. MAY STILL SEE
SOME STRONGER WIND GUSTS...THOUGH. HAVE RAISED PRECIPITATION CHANCES
UP FOR THE EVENING HOURS GIVEN VERY GOOD MODEL CONSENSUS FOR THIS
CONVECTION. KEPT SOME PRECIPITATION CHANCES GOING OVERNIGHT TOO
ALONG AND NORTH OF I-94 WHERE A FRONTOGENESIS BAND LOOKS TO SETUP ON
THE NORTH SIDE OF THE SHORTWAVE. LOOK FOR COOLER TEMPERATURES
TONIGHT AS COLDER AIR RUSHES IN BEHIND THE LINE OF CONVECTION. IN
FACT...925MB TEMPS COOL AS MUCH AS 10C ON A BRISK 30-40 KT 925MB
NORTHWEST WIND.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 250 AM CDT SAT SEP 20 2014
MAIN CONCERNS ARE ON PRECIPITATION POTENTIAL FOR SUNDAY...FOLLOWED
BY TEMPERATURES AND VALLEY FOG POTENTIAL SUNDAY NIGHT AND BEYOND.
ANOTHER POTENT SHORTWAVE LOOKS TO FOLLOW QUICKLY ON THE HEELS OF THE
ONE MOVING THROUGH THE FORECAST AREA TONIGHT. THIS SHORTWAVE...
CURRENTLY IN NORTHERN SASKATCHEWAN...IS PROGGED TO DROP SOUTH
THROUGH THE FORECAST AREA SUNDAY MORNING. THIS SHORTWAVE WILL HELP
TO PULL THE FRONTOGENESIS BAND AND ASSOCIATED SURFACE COLD FRONT
SOUTHWARD THROUGH THE FORECAST AREA DURING THE MORNING HOURS.
APPEARS THE BULK OF THE RAIN/SHOWER ACTIVITY WITH THE BAND WILL BE
CONFINED TO WISCONSIN...BUT SOME MAY EVEN CREEP ACROSS THE MS RIVER
AS SUGGESTED BY THE 20.00Z ECMWF/CANADIAN. HAVE RAISED PRECIPITATION
CHANCES UPWARDS AND FURTHER INCREASES MAY BE NECESSARY. OVERALL
AMOUNTS LOOK TO BE FAIRLY LIGHT...THOUGH. THIS FRONTAL BOUNDARY
DROPPING SOUTH...925MB TEMPS ONLY TOPPING OUT FROM 10-12C AT 00Z
MONDAY...A BREEZY NORTH WIND AND A DECENT AMOUNT OF SUN NOT
OCCURRING UNTIL LATE IN THE DAY WILL YIELD MUCH COOLER CONDITIONS
COMPARED TO TODAY.
MODELS REMAIN IN GOOD AGREEMENT IN BUILDING HIGH PRESSURE INTO THE
FORECAST AREA FOR SUNDAY NIGHT THROUGH TUESDAY. THIS IS IN RESPONSE
TO THE UPPER RIDGE OVER THE WESTERN THIRD OF THE U.S. MARCHING EAST
INTO MN AND IA BY 12Z TUE. THE MAIN CENTER OF THE HIGH LOOKS TO
TRACK JUST SOUTH OF THE AREA...BUT THE GRADIENT RELAXES ENOUGH TO
ALLOW FOR DECOUPLING BOTH NIGHTS. SOME CLOUDS COULD DRIFT ACROSS
BOTH NIGHTS...BUT IT APPEARS ENOUGH PERIOD OF CLEAR SKIES SHOULD
EXIST FOR VALLEY FOG TO FORM...ESPECIALLY IN THE TRIBUTARIES. SUNDAY
NIGHT WILL BE THE COOLER OF THE TWO NIGHTS DUE TO AIRMASS
MODIFICATION TAKING PLACE ON MONDAY. THE TYPICAL COLD SPOTS IN
CENTRAL WI COULD DIP INTO THE MID/UPPER 30S SUNDAY NIGHT. 925MB
TEMPS OF 12-14C ON MONDAY WITH MORE SUN WILL ALLOW HIGHS TO TOP OUT
IN THE 60S TO LOW 70S...WARMEST IN VALLEYS. THESE 925MB TEMPS CLIMB
ANOTHER 1-2C ON TUESDAY...RESULTING IN A SIMILAR BUMP UP IN HIGHS.
IN GENERAL THE WEATHER REMAINS FAIRLY QUIET FROM TUESDAY NIGHT RIGHT
INTO NEXT WEEKEND...THANKS TO SIGNIFICANT UPPER RIDGING BUILDING UP
OVER THE EASTERN TWO THIRDS OF THE U.S.. IN FACT...MOST LONG RANGE
GUIDANCE IS SUGGESTING A 590 DAM 500MB HIGH TO FORM OVER MICHIGAN BY
00Z SATURDAY...WHICH WOULD BE ABOUT 2 STANDARD DEVIATIONS ABOVE
NORMAL. THIS IS ALL A RESULT OF A VERY DEEP TROUGH DEVELOPING ALONG
THE WEST COAST OF THE U.S....SOMETHING THAT HASNT BEEN SEEN FOR
QUITE SOME TIME. THE ONLY REAL ISSUE TO WORRY ABOUT IS THE CURRENT
UPPER LOW OFF THE CALIFORNIA COAST...WHICH MODELS TRY TO BRING
THROUGH THE FORECAST AREA IN A WEAKENING STATE CENTERED AROUND
WEDNESDAY. HAVE MAINTAINED SOME LOW PRECIPITATION CHANCES ASSOCIATED
WITH THIS FEATURE. DESPITE THE RISING 500MB HEIGHTS...IT TAKES
AWHILE FOR A SIMILAR RESPONSE TO 850MB TEMPS...PARTIALLY DUE TO THAT
UPPER LOW LIFTING THROUGH. THUS...TEMPERATURES HOLD NEAR SEASONABLE
NORMALS UNTIL THE END OF THE WEEK. FRIDAY...SATURDAY AND SUNDAY ALL
LOOK ABOVE NORMAL WITH HIGHS POSSIBLY APPROACHING 80.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1134 PM CDT FRI SEP 19 2014
ACTIVITY HAS UPSCALED ACROSS NORTHWEST IOWA AND SOUTHERN
MINNESOTA SIMILAR TO WHAT THE MESO SCALE MODELS WERE SHOWING. AS
THE CURRENT ACTIVITY CONTINUES TO MOVE EAST...EXPECT THAT KRST
SHOULD BE IMPACTED BY SOME STORMS THROUGH ABOUT 07Z OR SO AND KLSE
THROUGH ABOUT 09Z WITH PRIMARILY MVFR CONDITIONS EXPECTED. SOME
UNCERTAINTY WHETHER ANY SHOWERS WILL LINGER/DEVELOP BEHIND THE
LINE OF STORMS. THE 20.02Z HRRR AND PREVIOUS RUNS HAVE BEEN
SHOWING GROWTH UP INTO WESTERN AND CENTRAL WISCONSIN WITH SOME
SHOWERS IMPACTING KLSE WHILE THE 20.00Z CR-NESTNAM KEEPS
EVERYTHING TO THE SOUTH. GIVEN THAT THE CURRENT ACTIVITY IS
FARTHER NORTH THAN THE CR-NESTNAM CURRENTLY INDICATES WILL HAVE
SOME LINGERING SHOWERS SIMILAR TO THE HRRR. VFR CONDITIONS SHOULD
THEN PREVAIL THROUGH SATURDAY BEHIND THE COLD FRONT WITH NORTHWEST
WINDS AND ENOUGH MIXING TO PRODUCE SOME GUSTS AT KRST. THE NEXT
SHORT WAVE TROUGH WILL RAPIDLY APPROACH FROM THE NORTHWEST
SATURDAY EVENING WITH MODERATE PV ADVECTION IN THE 500-300 MB
LAYER. THIS IS EXPECTED TO PRODUCE SOME SHOWERS AND HAVE INCLUDED
A VCSH FOR THE LAST HALF OF SATURDAY EVENING FOR BOTH SITES.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1134 PM CDT FRI SEP 19 2014
.SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)
ISSUED AT 222 PM CDT FRI SEP 19 2014
CONCERN FOCUSED ON CONVECTION/SEVERE POTENTIAL TONIGHT.
WATER VAPOR/RAP 500MB ANALYSIS SHOWING A FAIRLY VIGOROUS MID-LEVEL
TROUGH MOVING EAST ACROSS THE DAKOTAS. AT THE SURFACE...LOW PRESSURE
WAS LOCATED OVER SOUTHERN MANITOBA CANADA WITH A TRAILING TROUGH
THROUGH THE EASTERN DAKOTAS INTO CENTRAL NEB. RADAR MOSAIC SHOWING
SCATTERED SHOWERS/ISOLATED THUNDER ACROSS PORTIONS OF ND INTO
NORTHERN MN IN RESPONSE TO CORRIDOR OF 850MB MOISTURE TRANSPORT/310K
ISENTROPIC LIFT AHEAD OF THE APPROACHING TROUGH. OTHERWISE...BREEZY
SOUTH WINDS IN PLACE ACROSS THE FORECAST AREA THIS AFTERNOON WITH
MOSTLY SUNNY SKIES. TEMPERATURES WERE IN THE UPPER 60S TO THE MIDDLE
70S.
FOR TONIGHT...LOOK FOR THAT MID-LEVEL/SURFACE TROUGH TO ROTATE
SOUTHEAST ACROSS THE AREA TONIGHT. MODELS OFFERING UP VARIOUS
SOLUTIONS ON CONVECTIVE SCHEMES BASED ON FAIRLY STRONG CAP IN PLACE.
THINKING WITH INCREASING 850MB MOISTURE TRANSPORT/EVENTUAL
STEEPENING OF MID-LEVEL LAPSE RATES AND LIFT WITH THE TROUGH
PASSAGE...THIS WILL BE ENOUGH FORCING TO SEE AT LEAST A SCATTERED
BAND OF THUNDERSTORMS. THINKING THIS CONVECTION WILL INITIALLY START
OUT ELEVATED IN NATURE ABOVE THE CAP...BUT THEN CAP WEAKENS LATE
THIS EVENING INTO THE OVERNIGHT HOURS ALLOWING FOR AN UPTICK IN
THUNDERSTORM COVERAGE. STILL THINKING THERE IS A MARGINAL SEVERE
THREAT. MODEL CONSENSUS SHOWING 0-3KM MUCAPE VALUES OF 1000-200J/KG
ALONG WITH EFFECTIVE BULK SHEAR AROUND 30KT. THIS COULD PRODUCE A
FEW VIGOROUS/ROTATING UPDRAFTS CAPABLE OF LARGER HAIL PRODUCTION
AND DAMAGING WIND POTENTIAL.
LINGERING SHOWERS/THUNDERSTORMS WILL BE POSSIBLE ACROSS SOUTHERN WI
INTO NORTHEAST IA ON SATURDAY AS THE TROUGH CONTINUES TO ROTATE
SOUTHEAST OUT OF THE AREA. FOR LATER SATURDAY AFTERNOON INTO
SATURDAY EVENING...MODELS SHOWING A FAIRLY COMPACT/VIGOROUS PV-
ANOMALY ROTATING SOUTHEAST OUT OF THE NORTHERN PLAINS IN OUR AREA.
THE BULK OF THE FORCING WITH THIS FEATURE SEEMS TO BE FOCUSED ALONG
AND NORTHEAST OF I-94. AS SUCH...WENT WITH THE LIKELIHOOD OF
SHOWERS/ISOLATED THUNDER NORTHEAST OF I-94 AND TAPERED TO LOWER-END
CHANCES ACROSS NORTHEAST IA/FAR SOUTHWEST WI. WITH THE WARMER START
TO SATURDAY...LOOK FOR HIGHS TO PERK UP INTO THE 70S TO A FEW LOWER
80S ALONG AND SOUTH OF I-90. LOOK FOR THE SHOWERS AND ISOLATED
STORMS TO TAPER OFF/MOVE EAST OF THE AREA BY MIDNIGHT SATURDAY
NIGHT WITH OVERNIGHT LOWS DIPPING INTO THE 50S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 222 PM CDT FRI SEP 19 2014
COOLER CYCLONIC FLOW ALOFT ON SUNDAY WILL PRODUCE COOLER
TEMPERATURES IN THE 60S ALONG WITH BREEZY NORTHWEST WINDS. ALSO
LOOKS LIKE THERE WILL ALSO BE ENOUGH INSTABILITY NORTHEAST OF I-94
TO PRODUCE A FEW SHOWERS.
HIGH PRESSURE BUILDS OVER THE UPPER MISSISSIPPI RIVER VALLEY REGION
SUNDAY NIGHT. CLEAR SKIES AND LIGHT/CALM WINDS WILL SET UP IDEAL
RADIATIONAL COOLING FOR AREAS OF FOG...ESPECIALLY FAVORED RIVER
VALLEY LOCATIONS AND THE SANDY/BOG COUNTRY OF CENTRAL WI. PLAN ON
LOWS IN THE LOWER 40S OVER CENTRAL WI...AND IN THE MIDDLE/UPPER 40S
ELSEWHERE ACROSS THE FORECAST AREA.
AFTER A COOL/POTENTIALLY FOGGY START...HIGH PRESSURE LOOKS TO
PROVIDE A DRY/QUIET/MOSTLY SUNNY MONDAY WITH HIGHS MIDDLE 60S TO
NEAR 70.
FOR TUESDAY THROUGH FRIDAY...A RIDGE OF HIGH PRESSURE TRIES TO
ESTABLISH ITSELF OVER THE CENTRAL CONUS. HOWEVER...MODELS SHOWING A
TROUGH EJECTING OUT OF THE INTERMOUNTAIN WEST INTO THE UPPER
MISSISSIPPI RIVER VALLEY BY WEDNESDAY INTO THURSDAY. BELIEVE THIS
MAY BE A BIT OVER DONE...BUT WILL GO WITH MODEL CONSENSUS AT THIS
POINT AND INCLUDE SMALL-END SHOWER/THUNDER CHANCES IN THE TUESDAY
NIGHT THROUGH THURSDAY PERIOD. AS THE TROUGH MOVES OFF TO THE
EAST...THE RIDGE RE-ESTABLISHES ITSELF ON FRIDAY FOR DRIER/WARMER
CONDITIONS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1134 PM CDT FRI SEP 19 2014
ACTIVITY HAS UPSCALED ACROSS NORTHWEST IOWA AND SOUTHERN
MINNESOTA SIMILAR TO WHAT THE MESO SCALE MODELS WERE SHOWING. AS
THE CURRENT ACTIVITY CONTINUES TO MOVE EAST...EXPECT THAT KRST
SHOULD BE IMPACTED BY SOME STORMS THROUGH ABOUT 07Z OR SO AND KLSE
THROUGH ABOUT 09Z WITH PRIMARILY MVFR CONDITIONS EXPECTED. SOME
UNCERTAINTY WHETHER ANY SHOWERS WILL LINGER/DEVELOP BEHIND THE
LINE OF STORMS. THE 20.02Z HRRR AND PREVIOUS RUNS HAVE BEEN
SHOWING GROWTH UP INTO WESTERN AND CENTRAL WISCONSIN WITH SOME
SHOWERS IMPACTING KLSE WHILE THE 20.00Z CR-NESTNAM KEEPS
EVERYTHING TO THE SOUTH. GIVEN THAT THE CURRENT ACTIVITY IS
FARTHER NORTH THAN THE CR-NESTNAM CURRENTLY INDICATES WILL HAVE
SOME LINGERING SHOWERS SIMILAR TO THE HRRR. VFR CONDITIONS SHOULD
THEN PREVAIL THROUGH SATURDAY BEHIND THE COLD FRONT WITH NORTHWEST
WINDS AND ENOUGH MIXING TO PRODUCE SOME GUSTS AT KRST. THE NEXT
SHORT WAVE TROUGH WILL RAPIDLY APPROACH FROM THE NORTHWEST
SATURDAY EVENING WITH MODERATE PV ADVECTION IN THE 500-300 MB
LAYER. THIS IS EXPECTED TO PRODUCE SOME SHOWERS AND HAVE INCLUDED
A VCSH FOR THE LAST HALF OF SATURDAY EVENING FOR BOTH SITES.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...04
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1109 PM CDT FRI SEP 19 2014
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.UPDATE...
ISSUED AT 854 PM CDT FRI SEP 19 2014
FORECAST FROM THE DAY SHIFT APPEARS TO BE ON TRACK. TSTMS HAVE
INCREASED OVER THE PAST HOUR IN WEST CENTRAL WI...WHERE STRONG
0-1 KM MOISTURE CONVERGENCE...THE RRQ OF A 90 KT JET STREAK AND
AN INSTABILITY AXIS (MUCAPE 1000-1500 J/KG) ARE ALIGNED. EXPECT
PCPN TO GRADUALLY SHIFT E/SE ACROSS THE FORECAST OVERNIGHT...
AS THE LLJ VEERS WEST AND THE RRQ OF THE UPPER JET PULLS THROUGH.
NOT SURE ABOUT THE COVERAGE OF THE SHRA/TSRA ACTIVITY YET...SO
WILL STICK WITH HIGH CHC POPS FOR NOW. WILL MONITOR OVER THE NEXT
HOUR AND SEE IF POPS NEED TO BE INCREASED.
STILL ANTICIPATE THE POSSIBILITY OF A FEW STRONG STORMS...AS
DEEP LAYER SHEAR IS 40-50+ KTS AND MID-LEVEL LAPSE RATES ARE
STEEP (7-8 C/KM). THE PRESENCE OF A 40-50 KT LLJ WILL ALSO
ENHANCE THE THREAT OF STRONG TSTM WINDS...ALTHOUGH MOST OF
THE INSTABILITY WILL BE ELEVATED.
&&
.SYNOPSIS...
ISSUED AT 243 PM CDT FRI SEP 19 2014
WARM AND A BIT MORE HUMID EARLY IN THE WEEKEND...THEN BRIEFLY
COOLER BEFORE TURNING MILD AND MAINLY DRY NEXT WEEK.
INITIALLY LOW- AMPLITUDE BAND OF WESTERLIES ACRS SRN CANADA AND
THE NRN CONUS WL UNDERGO AMPLIFICATION DURING THE WEEKEND...WITH
UPR RIDGE BUILDING OVER THE INTERMOUNTAIN WEST AND A TROF
DEEPENING THROUGH THE GREAT LAKES RGN. A SLOW PROGRESSION OF THE
LARGE SCALE FEATURES IS EXPECTED...WITH THE POSITIVE ANOMALY ASSOC
WITH THE WRN RIDGE SHIFTG TO THE JAMES BAY REGION BY THE MIDDLE OF
NEXT WEEK...BEFORE THE PROGRESSION SLOWS. THAT WL LEAVE HIGH UPR
HEIGHTS ACRS THE ERN CONUS LATE NEXT WEEK THROUGH THE FOLLOWING
WEEKEND...WITH THE MAIN WESTERLIES WELL TO THE N ACRS CANADA.
TEMPS WL START OUT ABV NORMAL...BRIEFLY DROP TO BLO NORMAL LEVELS
LATE IN THE WEEKEND...THEN WARM BACK TO ABV NORMAL FOR MOST OF
NEXT WEEK. THE MAIN OPPORTUNITY FOR PCPN WL OCCUR EARLY IN THE
FCST PERIOD. UPR RIDGING DOMINATING THE AREA THEREAFTER WL ALLOW
FOR ONLY SCT LGT SHOWERS AT MOST...AND QUITE POSSIBLY TOTALLY DRY
WEATHER FOR THE MIDDLE TO LATTER PART OF THE PERIOD.
&&
.SHORT TERM...TONIGHT AND SATURDAY
ISSUED AT 243 PM CDT FRI SEP 19 2014
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW FLATTENED
MID-LEVEL TROUGHING ACROSS THE NORTHERN PART OF THE COUNTRY FROM
MONTANA TO LAKE SUPERIOR. WITHIN THIS TROUGHING...SEVERAL
SHORTWAVES ARE MOVING TO THE EAST AND ARE CREATING AREAS OF SHOWERS
AND STORMS. ONE AREA IS LOCATED OVER NORTHERN MINNESOTA WHILE
ANOTHER CLUSTER IS OVER FAR NORTHERN LAKE SUPERIOR. A FEW SHOWERS
EXTENDING SOUTHWARD FROM THE LATTER CLUSTER ARE PASSING OVER N-C
WISCONSIN EARLY THIS AFTERNOON. FOR THE REST OF THE AFTERNOON...THE
AREA TO FOCUS ON IS OVER MINNESOTA WHERE PWATS ARE GREATER THAN 1.50
INCHES BUT STILL WAITING FOR INSTABILITY TO ARRIVE. IF THIS AREA
CAN DESTABILIZE LATER THIS AFTERNOON...COULD SEE SOME STRONG STORMS
DEVELOP. THE SURFACE COLD FRONT TRAILS THIS AREA AND REMAINS OVER
THE EASTERN DAKOTAS. AS THE UPSTREAM SHORTWAVES AND COLD FRONT MOVE
THROUGH THE REGION OVER THE NEXT 24 HOURS...PRECIP TIMING AND
THUNDERSTORM POTENTIAL ARE THE MAIN FORECAST CONCERNS.
TONIGHT...PIECES OF SHORTWAVE ENERGY OVER NORTHERN PLAINS WILL MOVE
INTO THE WESTERN GREAT LAKES REGION THIS EVENING. ALONG THE LEADING
EDGE OF THIS ENERGY...MODELS SHOW A RIBBON OF DEEP MOISTURE WITH
PWATS APPROACHING 1.75 INCHES ALONG WITH INCREASING FORCING IN THE
FORM OF MID-LEVEL FGEN AND UPPER DIVERGENCE WILL SAG SOUTHEAST
ACROSS THE NORTHWEST HALF OF WISCONSIN THIS EVENING AND NORTHEAST
WISCONSIN OVERNIGHT. VARIOUS MODELS INCLUDING THE RUC/SREF/NAM ALL
DEVELOP MORE WIDESPREAD COVERAGE OF SHOWERS AND STORMS LATE THIS
AFTERNOON OR EARLY THIS EVENING OVER WESTERN WISCONSIN COINCIDENT
WITH A RIBBON OF ELEVATED CAPES UPWARDS OF 1000 J/KG. SPC
HIGHLIGHTS THIS AREA FOR A THREAT OF STRONG TO NEAR SEVERE STORMS.
THE FORCING AND RIBBON OF DEEP MOISTURE LOOK TO OUTRUN THIS
INSTABILITY AXIS BY LATE IN THE EVENING AND OVERNIGHT...BUT NOT OUT
OF THE QUESTION THAT A FEW STRONG STORMS (IF THEY DEVELOP) COULD
MAKE IT INTO CENTRAL WISCONSIN BY MID TO LATE EVENING BEFORE
WEAKENING THEREAFTER. WITH THE JET OVERHEAD...STRONG GUSTY WINDS
WOULD BE THE MAIN THREAT FOLLOWED BY SMALL HAIL. COVERAGE OF
SHOWERS AND STORMS SHOULD DIMINISH TO SCATTERED BY THE TIME THEY
REACH NE WISCONSIN OVERNIGHT. BEHIND THE STORMS...A LOW STRATUS
DECK SHOULD SPREAD ACROSS THE AREA...WHICH COULD ALSO CREATE PATCHY
FOG IN SPOTS. A WARM NIGHT WITH LOWS IN THE UPPER 50S TO LOWER 60S.
SATURDAY...A FEW SHOWERS AND ISOLATED STORMS WILL BE EXITING
EAST-CENTRAL WISCONSIN EARLY IN THE MORNING AND MAY ALSO HAVE A FEW
SHOWERS OVER N-C WISCONSIN AS WELL. BUT OTHERWISE...THE DAY SHOULD
START OUT RATHER CLOUDY WITH A LOW OVERCAST DECK IN PLACE. THE LOW
STRATUS WILL LIKELY SLOW THE HEATING CURVE FOR A FEW HOURS IN THE
MORNING...BUT SHOULD LIFT WITH MIXING BY MID TO LATE MORNING. THE
TRAILING SURFACE FRONT WILL BE MOVING ACROSS CENTRAL AND
NORTH-CENTRAL WISCONSIN DURING THIS TIME BUT THE CLOUD COVER SHOULD
KEEP THE FRONT RELATIVELY INACTIVE. AS IT REACHES NORTHEAST AND
EAST-CENTRAL WISCONSIN BY MIDDAY TO EARLY AFTERNOON...POTENTIAL WILL
BE THERE FOR DAYTIME HEATING TO CREATE SURFACE BASED INSTABILITY
OVER THAT PART OF THE STATE. THE NAM GENERATES CLOSE TO 1500 J/KG
OF ML CAPE OVER EAST-CENTRAL WISCONSIN ASSUMING TEMPERATURES CAN
REACH INTO THE MIDDLE 70S. BUT CONVERGENCE ALONG THE FRONT IS
RELATIVELY WEAK AND THERE WILL LIKELY BE A CAP TO OVERCOME. SO
THINK THE POTENTIAL FOR REDEVELOPMENT OF THUNDERSTORMS IS PRETTY LOW
BECAUSE OF THESE FACTORS. HIGHS IN THE UPPER 60S NORTH TO MIDDLE OR
UPPER 70S SOUTH.
.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
ISSUED AT 243 PM CDT FRI SEP 19 2014
UPR SPEED MAX AND SHARPENING SHRTWV WL DIG SE ACRS THE FCST AREA
SAT NGT AS LARGE SCALE AMPLIFICATION OCCURS. THE STG DYNAMICS WL
BE FAVORABLE FOR PCPN...ESP ACRS THE N. RAISED POPS TO
CATEGORICAL THERE...TAPERING TO A HIGH-END CHC ACRS THE S.
INSTABILITY WON/T BE GREAT...BUT WL PROBABLY BE SUFFICIENT FOR
THUNDER GIVEN THE DYANMICS. TRENDED TOWARD THE HIGH QPFS OF THE
MODELS WITH THE BETTER DEFINED SFC REFLECTION.
BLUSTERY...CLDY...AND MUCH COOLER CONDITIONS ARE LIKELY SUN...
WITH LINGERING SHRA OVER MAINLY THE N/NE/E. TRIMMED MAX
TEMPS...BUT WOULD NOT BE SURPRISED IF THEY END UP EVENTUALLY
NEEDING A BIT MORE PRUNING.
TEMPS SUN NGT TRICKY BECAUSE THEY/LL DEPEND ON CLDS. THINK THERE
WL STILL BE ENOUGH OF A NW FLOW DOWN ACRS LAKE SUPERIOR TO KEEP
THINGS A LITTLE CLOUDIER THAN MUCH OF THE GUIDANCE IS
INDICATING...SO DID NOT TAKE LOWS DOWN TOO FAR. A FROST/FREEZE
WOULD CERTAINLY BE POSSIBLE ACRS MUCH OF THE AREA IF WE TOTALLY
CLEAR OUT.
UPR HEIGHTS REBOUND QUICKLY LATER SUN NGT AND MON...SO THE COOLER
WX WL BE SHORT-LIVED. MODELS HINT THAT WK SHRTWVS WORKING ARND
THE WRN FLANK OF THE UPR RIDGE COULD BRUSH THE AREA AT TIMES.
THAT RESULTED IN SOME LOW-CHC POPS IN THE EXTENDED FCST
INITIALIZATION GRIDS. THAT/S CERTAINLY HARD TO RULE OUT SO LET
THOSE RIDE IN THE FCST. BUT OVERALL...FORCING WL BE WEAK AND
MOISTURE LIMITED...SO EXPECTING A MAINLY DRY PERIOD WITH ABV
NORMAL TEMPS.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1103 PM CDT FRI SEP 19 2014
LLWS WILL CONTINUE TONIGHT...BUT SHOULD WEAKEN AT THE WESTERN TAF
SITES BY 09Z-10Z...AND AT THE EASTERN TAF SITES BY 12Z-14Z/SAT.
SCT SHOWERS AND TSTMS ARE EXPECTED TO MOVE THROUGH THE FORECAST
AREA OVERNIGHT. DID ADD A TEMPO GROUP FOR TSTMS AT CWA/AUW EARLY
THIS MORNING (LOW-LEVEL JET AND UPPER JET STREAK)...AND A PROB30
GROUP FOR TSTMS AT GRB/ATW/MTW IN THE EARLY AFTERNOON (COLD
FRONTAL PASSAGE). MVFR CONDITIONS MAY ACCOMPANY THE SHOWERS AND
STORMS. STRATUS IS EXPECTED TO SPREAD ACROSS THE FORECAST AREA
OVERNIGHT INTO EARLY SATURDAY. IFR CONDITIONS ARE POSSIBLE...
ESPECIALLY OVER NC/C WI. EXPECT LOW CIGS TO GRADUALLY IMPROVE AS
THE COLD FRONT MOVES THROUGH THE REGION ON SATURDAY.
A STRONG UPPER LEVEL DISTURBANCE WILL SPREAD SHOWERS AND ISOLD
THUNDERSTORMS OVER THE REGION SATURDAY EVENING. MVFR/IFR
CONDITIONS ARE POSSIBLE.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE.........KIECKBUSCH
SYNOPSIS.......SKOWRONSKI
SHORT TERM.....MPC
LONG TERM......SKOWRONSKI
AVIATION.......KIECKBUSCH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
636 PM MDT SUN SEP 21 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 330 PM MDT SUN SEP 21 2014
AFTERNOON SATELLITE IMAGES SHOW WELL-DEFINED LOW PRESSURE AREA
LIFTING NORTH/NORTHEAST ACROSS THE GREAT BASIN...WITH ARM OF
MOISTURE ASSOCIATED WITH WEAK SHORTWAVE EXTENDING TO ITS N AND E
ADVECTING INTO THE INTERMOUNTAIN WEST. SHOWERS WERE OBSERVED AT
KCAG EARLIER THIS AFTERNOON...AND KCYS/KGJX 88D RETURNS SUGGEST
THIS MOISTURE HAS MADE IT INTO THE SIERRA MADRES AND ADJACENT WRN
FOOTHILL LOCATIONS. 20Z SFC ANALYSIS SHOWS 1026MB ACROSS THE
DAKOTAS AND NEBRASKA WITH RETURN FLOW ALONG THE FRONT RANGE AND A
WELL DEFINED SFC TROF BANKED UP ALONG THE EAST SLOPES OF THE SNOWY
RANGE. LLVL CONVERGENCE ALONG THIS SFC TROF HAS COMBINED WITH 250+
J/KG OF SBCAPE AS ANALYZED FROM SPC MESOANALYSIS TO SPARK A COUPLE
OF POCKETS OF DEEPER CONVECTION IN THE VICINITY OF CENTENNIAL/
WOODS LANDING/ALBANY OVR THE PAST FEW HOURS. LOW CENTER WILL REACH
IDAHO BY LATE TONIGHT...WITH ARM OF MOISTURE ADVECTION CONTINUING
FROM SW TO NE INTO THE CWFA. HIGH CLOUDS HAVE ALREADY BEEN ON THE
INCREASE ACROSS THE AREA...BUT SHOULD SEE THESE LOWER AND THICKEN
OVERNIGHT. ASCENT ASSOCIATED WITH THE UPPER-LOW WILL INCREASE
TONIGHT...SO WILL SEE SHOWERS AND STORMS INCREASE ESPECIALLY ALONG
AND WEST OF THE LARAMIE RANGE AS WELL. HAVE ALSO ADDED SOME FOG TO
THE SRN LARAMIE RANGE PER LATEST HRRR OUTPUT. LIGHTNING WAS EVIDENT
ACROSS SW COLORADO LAST NIGHT...SO IT MAKES SENSE TO KEEP IT
TONIGHT UP HERE TONIGHT. 12Z MODEL OUTPUT HAS TRENDED SLOWER IN
SPREADING RAIN CHANCES OUT ONTO THE ERN PLAINS...WHICH WILL LIKELY
NOW HOLD OFF NOW UNTIL SOMETIME MONDAY MORNING.
UPPER LOW WOBBLES THRU THE COWBOY STATE ON MONDAY...WHICH WILL
EFFECTIVELY SHARPEN AND ENHANCE AFTERNOON CONVECTION ALONG THE
PREFRONTAL SFC TROF/PACIFIC FRONT. BEST CONVECTIVE CHANCES ON
MONDAY WILL BE TIED CLOSELY TO THE LOCATION OF THIS TROF...WHICH
WILL BE WEST OF THE LARAMIE RANGE IN THE MORNING BEFORE PUSHING
EAST OF THE LARAMIE RANGE MONDAY. PROGD INSTABILITY PARAMETERS
LOOK FAIRLY MEAGER...WITH SBCAPES TOPPING OUT AROUND 500 J/KG.
HOWEVER...WITH THE PROXIMITY OF THE UPPER WAVE COMBINED WITH
DAYTIME DESTABILIZATION...WOULD EXPECT PERHAPS SOME MORE ORGANIZED
CONVECTION FOR LOCATIONS EAST OF THE MOUNTAINS. SHOWER AND
THUNDERSTORM CHANCES WILL DECREASE SOME FROM WEST TO EAST MONDAY
NIGHT.
UPPER-LOW WILL DEPART DURING THE DAY ON TUESDAY...BRINGING
PRECIPITATION CHANCES TO AN END FROM WEST TO EAST. OTHERWISE...
TUESDAY WILL LIKELY TURN A BIT BREEZY AND WINDS TURN WEST BEHIND
THE DEPARTING PREFRONTAL SFC TROF/PACIFIC FRONT. WIND GUSTS OF 20
TO 35 MPH CAN BE EXPECTED DURING THE AFTERNOON. MONDAY WILL BE THE
COOLEST DAY OF THE WEEK AS CLOUD COVER PROHIBITS THE AMOUNT OF
INSOLATION. EVEN SO...EXPECT HIGH TEMPERATURES IN THE 70S/LOW 80S.
HIGHS WILL WARM ABOUT 5 DEGREES OR SO ON TUESDAY...YIELDING MID
70S TO MID 80S.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 330 PM MDT SUN SEP 21 2014
NOT A WHOLE LOT OF CHANGE IN THE MODEL GUIDANCE THROUGH THE FIRST
HALF OF THE EXTENDED PERIOD. SUBSTANTIAL RIDGE BUILDS OVER THE
INTERMOUNTAIN WEST ON WED AND THIS WILL CAUSE TEMPS TO RISE TO
AROUND 10 DEGREES ABOVE NORMAL ACROSS THE CWA. WINDS WILL BE LIGHT
ON WED WITH WEAK SFC GRADIENTS AND FLOW ALOFT. NOT MUCH CHANGE FOR
THURS EXCEPT THAT SOUTH-TO-SOUTHEAST WINDS WILL BE BREEZY DURING
THE AFTN ACROSS THE PLAINS DUE TO PRESSURE FALLS OVER MONTANA. THE
MODELS CONTINUE TO EXHIBIT DIFFERENCES AS WE HEAD INTO NEXT
WEEKEND. THE GFS IS YET AGAIN THE MOST PROGRESSIVE WITH THE
WESTERN UPPER TROUGH...MOVING ITS AXIS TO NEAR UTAH BY SAT.
WIDESPREAD PRECIP IS PROGGED BEHIND THE COLD FRONTAL PASSAGE ON
SAT NIGHT...SOME OF WHICH COULD BE SNOW OVER THE MTNS. THE ECMWF
SHOWS A CUTOFF OVER CALIFORNIA ON SAT WHICH WOULD SIGNIFICANTLY
DELAY A COOLDOWN AND IS A MUCH DRIER SOLN. WITH SUCH BIG
DIFFERENCES ALMOST A WEEK OUT DECIDED TO INCREASE CLOUD COVER ON
SAT BUT KEEP ONLY SLIGHT CHANCE POPS ON SAT NIGHT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY AFTERNOON)
ISSUED AT 636 PM MDT SUN SEP 21 2014
SHOWERS AND T-STORMS WILL CONTINUE OFF AND ON TONIGHT FOR AREAS
ALONG AND WEST OF THE LARAMIE RANGE AS A PACIFIC STORM SYSTEM
APPROACHES FROM THE WEST. VFR CONDITIONS SHOULD PREVAIL AS THIS
ACTIVITY IS EXPECTED TO REMAIN WEAK...WITH THE EXCEPTION OF KCYS
AS PATCHY IFR STRATUS IS POSSIBLE OVERNIGHT IN SOUTH-SOUTHEAST
UPSLOPE FLOW. IN ADDITION...WINDS AT MOST SITES WILL INCREASE
OVERNIGHT...WITH SPEEDS OF 10 TO 15 KTS LIKELY THROUGH THE
MORNING. GUSTS OF 20 TO 30 KTS WILL THEN BE POSSIBLE THROUGH
MONDAY AFTERNOON...WITH T-STORM COVERAGE TO INCREASE ACROSS THE
EASTERN PLAINS.
&&
.FIRE WEATHER...
ISSUED AT 330 PM MDT SUN SEP 21 2014
SHOWER AND THUNDERSTORM CHANCES TO INCREASE TONIGHT AND MONDAY.
THIS WILL KEEP FIRE WEATHER CONCERNS MINIMAL THROUGH AT LEAST
TUESDAY. AN AREA OF LOW PRESSURE WILL BRING RELATIVELY GOOD CHANCES
OF WETTING RAINS TO THE DISTRICTS TONIGHT THROUGH MONDAY EVENING.
DO NOT ANTICIPATE SIGNIFICANT RAINFALL TOTALS...HOWEVER A FEW
TENTHS OF AN INCH WILL BE A POSSIBILITY IN THE HEAVIEST
SHOWERS/STORMS. DRIER AND WARMER CONDITIONS WILL RETURN TUE-FRI.
EVEN SO MINIMUM RELATIVE HUMIDITIES ARE STILL ONLY EXPECTED TO
BOTTOM OUT NEAR 20 PERCENT.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...HAHN
LONG TERM...FINCH
AVIATION...RJM
FIRE WEATHER...HAHN
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1204 AM MDT SAT SEP 20 2014
.UPDATE...
ISSUED AT 913 PM MDT FRI SEP 19 2014
A NUMBER OF OUTFLOW BOUNDARIES HAVE BEEN SITUATED ACROSS EASTERN
LARAMIE COUNTY THIS EVENING...AND INTERACTED WITH WHAT APPEARS
TO BE A PREFRONTAL TROUGH MOVING EAST ACROSS THE CWA TO MAINTAIN
DEVELOPMENT OF SCATTERED SHOWERS AND THUNDERSTORMS ALONG THE
I-80 CORRIDOR. A FEW SHOWERS CONTINUE TO POP UP AT THIS HOUR FROM
EASTERN LARAMIE COUNTY AND POINTS TO THE EAST...BUT THINK THE
MAIN SFC AND MID LEVEL FORCING HAS PUSHED SOUTH AND EAST OF THE
CWA BASED ON SATELLITE IMAGERY. WILL KEEP WIDELY SCATTERED
COVERAGE FOR SHOWERS WITH MENTION OF ISO-T THROUGH 06Z FOR THIS
AREA...BUT THIS MAY BE OVERLY OPTIMISTIC BASED ON RADAR TRENDS
ALREADY TAKING A DOWNWARD TURN. THE MAIN SFC COLD FRONT LOOKS TO
BE JUST NORTH OF THE CWA AND WILL CONTINUE TO MOVE SOUTH
OVERNIGHT. FOCUSED HIGHEST CLOUD COVER ALONG THE LARAMIE RANGE
THROUGH THE EARLY MORNING HOURS AS MODELS HINT AT A SCT STRATUS
DECK ACCOMPANYING THE FRONT ALONG WITH NORTH-NORTHEAST UPSLOPE
FLOW. OTHERWISE...FORECAST IS IN GOOD SHAPE.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 350 PM MDT FRI SEP 19 2014
NEAR TERM FORECAST CONCERNS REVOLVE AROUND PCPN CHANCES FOR THE REST
OF THE AFTN AND EVE. WATER VAPOR SATELLITE SHOWS A WELL PRONOUNCED
UPPER-LEVEL SHORTWAVE MOVING ACROSS NORTHWEST WY AT 20Z. ASSOCIATED
SFC COLD FRONT HAS MADE LITTLE FORWARD PROGRESS THIS AFTN...ANALYZED
FROM SOUTHWEST TO NORTHEAST ACROSS THE STATE. THIS FEATURE COMBINED
WITH MODEST LARGER SCALE SUPPORT SHOULD SERVE AS A FOCUS FOR SHOWER
AND TSTM DEVELOPMENT IN THE NEXT FEW HOURS. HRRR HAS BEEN CONSISTENT
WITH SHOWING ISOLATED ACTIVITY FROM SOUTHEAST WY INTO THE SOUTHERN
NE PANHANDLE BETWEEN 22Z AND 02Z. LACK OF SUBSTANTIAL FORCING SHOULD
KEEP THINGS ISOLATED. GFS AND NAM BUFKIT SOUNDINGS INDICATE INVERTED
V LLVL PROFILES OVER MUCH OF THE CWA. DCAPES AROUND 1300 J/KG ON THE
LATEST SPC MESOANALYSIS SUGGESTS GUSTY OUTFLOW WINDS COULD BE A BIT
OF A PROBLEM TONIGHT. DID NOT MENTION IN THE GRIDS WITH COVERAGE NOT
HIGH ENOUGH TO WARRANT.
COLD FRONT IS PROGGED TO SWEEP ACROSS THE CWA BY LATE TONIGHT. DRIER
AIR WILL SLOWLY WORK INTO THE AREA...ENDING CHANCES FOR PCPN FROM NW
TO SE BY 06Z SAT. GFS AND NAM SHOW H7 TEMPS COOLING TO 6 TO 8 DEG C
OVER THE PLAINS BY SAT AFTN...DOWN FROM AROUND TODAY`S 13 C OVER CYS
PER A RECENT LAPS SOUNDING ANALYSIS. DRY COLUMN OVERHEAD FOR SAT AS
HIGH-AMPLITUDE UPPER RIDGING TAKES OVER...SO LOOKING AT MOSTLY SUNNY
SKIES AND A SUBSTANTIAL COOL DOWN FROM TODAY`S HIGHS. NEXT CONCERN IS
A LARGE CUTOFF LOW CURRENTLY SEEN ON WATER VAPOR SATELLITE OVER WEST
CENTRAL CALIFORNIA. THIS FEATURE WILL LIFT SLOWLY NORTHEAST ON SUN
WITH INCREASING 700-300 MILLIBAR MOISTURE OVER CARBON COUNTY BY 12Z.
MOISTURE AND QG ASCENT OVERSPREADS THE CWA THROUGH THE REMAINDER OF
THE FCST PERIOD. LLVL UPSLOPE AND SOME CLOUD COVER SUGGESTS SUN AFTN
SHOULD BE QUITE COOL. THE MAJORITY OF MOS GUIDANCE SUGGESTS HIGHS AT
70F OR BELOW AS A GENERAL RULE...SO TRENDED LOWER ON TEMPS. ISOLATED
TO SCATTERED SHOWER AND THUNDERSTORM ACTIVITY WILL INCREASE FROM SW
TO NE DURING THAT TIME FRAME.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 350 PM MDT FRI SEP 19 2014
MODELS ARE IN GOOD AGREEMENT AT SHOWING THE UPPER LOW OVER THE
GREAT BASIN MOVING EASTWARD ON MON AND LOCATED OVER NORTHERN WY BY
THE AFTN. GOOD UPPER LEVEL DIFFLUENCE WILL DEVELOP DURING THE
DAY...ESPECIALLY ACROSS THE PLAINS. SCATTERED SHOWERS AND TSTMS
WILL BE POSSIBLE THROUGH THE DAY. LOOKING AT SOUNDINGS AND
CONVECTIVE PARAMETERS OVER THE NEBRASKA PANHANDLE...COULD SEE A
FEW STRONGER STORMS WITH SMALL HAIL. MID LEVEL LOW CONTINUES EASTWARD
INTO SOUTH DAKOTA ON MON NIGHT AND TUES WITH LARGE SCALE
SUBSIDENCE FOLLOWING. PRECIP CHANCES COME DOWN ON TUES AS THE BEST LIFT
AND MOISTURE IS WELL EAST...HOWEVER KEPT SLIGHT CHANCE POPS DURING
TH AFTN WITH WEAK INSTABILITY COMBINED WITH MODEST MID LEVEL
MOISTURE ON THE BACKSIDE OF THE LOW. IT WILL BE BREEZY ON TUES
WITH ENHANCED NORTHWEST FLOW ALOFT AND GOOD MIXING. THE REMAINDER
OF THE LONG TERM WILL FEATURE INCREASING HEIGHTS AS A RIDGE BUILDS
OVER THE INTERMOUNTAIN WEST IN ADVANCE OF A LARGE SCALE TROUGH OFF
THE WEST COAST. TEMPS WILL BE SLIGHTLY ABOVE SEASONAL NORMS AND
WINDS WILL BE RELATIVELY WEAK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1200 AM MDT SAT SEP 20 2014
WINDS WILL SHIFT TO NORTH AND NORTHEAST WITH THE PASSAGE OF A WEAK
COLD FRONT. UPSLOPE MAY LEAD TO SCATTERED LOW STRATUS ALONG THE
LARAMIE RANGE BY SATURDAY MORNING. OTHERWISE...VFR WILL PREVAIL.
EAST TO NORTHEAST WINDS WILL BE BREEZY AT TIMES FOR THE PLAINS
SATURDAY.
&&
.FIRE WEATHER...
ISSUED AT 350 PM MDT FRI SEP 19 2014
A WEAK COLD FRONT WILL MOVE ACROSS SOUTHEAST WY AND THE WESTERN NE
PANHANDLE TONIGHT. ISOLATED TO WIDELY SCATTERED SHOWERS AND STORMS
WILL BE POSSIBLE THROUGH THE AFTN AND EVE WITH GUSTY OUTFLOW WINDS
THE PRIMARY HAZARD. COOLER AND DRIER FOR SAT IN THE POST-FRONTAL AIR
MASS WITH LITTLE OR NO CHANCE FOR PCPN. THE NEXT CHANCE FOR WETTING
RAINS WILL BE FROM SUN NIGHT THROUGH TUE AS A POTENT WEATHER SYSTEM
MOVES SLOWLY NORTHEAST ACROSS THE REGION. CRITICAL FIRE WEATHER IS
NOT EXPECTED IN THE FORESEEABLE FUTURE.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...RJM
SHORT TERM...HAMMER
LONG TERM...FINCH
AVIATION...JAMSKI
FIRE WEATHER...HAMMER
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1110 PM MDT SUN SEP 21 2014
.UPDATE...
ISSUED AT 856 PM MDT SUN SEP 21 2014
UPDATED TO ADJUST POPS BASED ON THE CURRENT RADAR AND SATELLITE
TRENDS. A LARGE UPPER LEVEL LOW IS SPINNING ACROSS NORTHEAST
NEVADA WITH AN UPPER DISTURBANCE IN THE FLOW LIFTING INTO THE FOUR
CORNERS REGION. AN INCREASE IN THUNDERSTORM ACTIVITY IS NOTED OVER
THE FOUR CORNERS WHICH WILL SPREAD EASTWARD ACROSS THE CONTINENTAL
DIVIDE THROUGH MIDNIGHT. THERE HAVE BEEN SOME LIGHT ECHOES OVER
THE I-25 CORRIDOR AND RATON MESA AREA...BUT NOTHING TOO ORGANIZED
AT THIS TIME. MODELS ARE ALL STILL GENERATING A DECENT BAND OF
SHOWERS AND THUNDERSTORMS LIFTING ACROSS THE AREA OVERNIGHT BUT
FEEL THEY MAY BE OVER DOING THINGS A BIT. FOR NOW HAVE THE HIGHEST
POPS AFTER MIDNIGHT ALONG THE SAN JUAN RANGE...WITH DECREASING
CHANCES AS YOU HEAD EAST INTO THE PLAINS. MODELS HAVE NOT HANDLED
OVERNIGHT CONVECTION WELL THE PAST COUPLE OF NIGHTS...SO WE WILL
SEE HOW THINGS UNFOLD OVER THE NEXT COUPLE OF HOURS. MOZLEY
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 322 PM MDT SUN SEP 21 2014
...HEAVY RAIN POSSIBLE TONIGHT OVER SAN JUAN MOUNTAINS...MARGINAL
SEVERE POSSIBLE ON PLAINS TOMORROW AFTERNOON...
CURRENTLY...
DRIER AIR NOTED OVER PLAINS AS DWPTS OVER FAR EC COLO IN THE
30S...WITH U40S/50S ALONG THE I-25 CORRIDOR. MTNS MAINLY IN THE
40S...WITH MUCH RICHER MOISTURE SW OF THE FCST AREA. AREA OF RAIN
OVER THE CONTDVD EARLIER HAS DISSIPATED...ALTHOUGH CONVECTIVE
SHOWERS WERE DEVELOPING OVER MOST OF THE HIGHER TRRN. A FEW ISOLD
POPS WERE NOTED OVER FAR N EL PASO COUNTY. A FEW CG FLASHES WERE
NOTED WITH THE DEVELOPING CONVECTION...BUT THE BRUNT OF THE INTENSE
LTG ACTIVITY WAS STILL ASSOCIATED WITH THE TROUGH BACK INTO E UTAH.
REST OF THIS AFTERNOON INTO TONIGHT...
MAIN CONCERN THIS PERIOD WILL BE THE MOUNTAINS ALONG THE
CONTDVD...ESPECIALLY THE SAN JUANS. ALL GUIDANCE IS INDICATING BEST
CHANCE OF HEAVY PRECIP WILL BE OVER THE SW FACING SLOPES OF THE SAN
JUANS. MOST OF THE PRGD HEAVY PRECIP WILL BE IN NWS GJT AREA OF
RESPONSIBILITY...BUT SOME OF THIS PRECIP WILL LIKELY MAKE IT OVER
THE DIVIDE. WILL WAIT TIL LATE THIS AFTERNOON TO DECIDE IF A FLASH
FLOOD WATCH IS NEEDED. PROS FOR A WATCH IS MODEL FCST...BUT WE (NWS
PUB) REALLY HAVE NOT RECEIVED HEAVY RAIN OVER THIS REGION SO SOILS
ARE NOT ALL THAT SATURATED.
18Z NAM HAS BEEN SHOWING LOTS OF PRECIP OVER THE GREATER PIKES PEAK
REGION BUT I AM DISCOUNTING THIS DUE TO ITS POOR PERFORMANCE THE
LAST SEVERAL RUNS. RAP GUIDANCE IS QUITE A BIT DRIER. GFS ALSO A LOT
DRIER PIKES PEAK REGION.
OVER THE REST OF THE REGION...I DONT THINK THE PLAINS WILL SEE MUCH
IN THE WAY OF PRECIP THE REST OF THIS AFTERNOON OR TONIGHT. SOME
SHOWERS WILL BE POSSIBLE MAINLY WEST OF THE INTERSTATE...AND ACROSS
N EL PASO COUNTY...BUT THE REST OF THE REGION SHOULD REMAIN DRY.
SOME LOW CLOUDS/FOG WILL BE POSSIBLE ACROSS N EL PASO COUNTY TONIGHT
GIVEN THE MOIST UPSLOPE FLOW.
TOMORROW....
TROUGH ALOFT WILL MOVE ACROSS THE REGION. IT APPEARS NOW THAT THE
SFC TROUGH WILL REMAIN IN COLORADO DURING PRIME HEATING AND WE WILL
LIKELY HAVE A BROKEN LINE OF CONVECTION MOVE ACROSS THE PLAINS
DURING THE AFTERNOON TIME PERIOD. SHEAR LOOKS GOOD BUT CAPE LOOKS
MARGINAL SO SVR THREAT WILL BE MINIMAL. QUITE A FEW CLOUDS MAY BE
OVER THE AREA TOMORROW AND THAT COULD LIMIT HEATING.
MOUNTAINS SHOULD GRADUALLY DRY OUT TOMORROW.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 322 PM MDT SUN SEP 21 2014
MONDAY NIGHT...THE UPPER LOW WILL TRACK E ACROSS WY AND INTO THE
DAKOTAS MON EVE...GRADUALLY BRINGING AN END TO PCPN FROM WEST TO
EAST. CONVECTION IS FORECAST TO BECOME ISOLATED BY MIDNIGHT ACROSS
THE FAR E PLAINS...THEN COME TO AN END EARLY TUE MORN ALONG THE
CO/KS BORDER.
TUESDAY AND WEDNESDAY...A RIDGE OF HIGH PRESSURE BUILDS OVER THE
REGION...ALLOWING FOR PREDOMINANTLY DRY CONDITIONS AND MAX TEMPS IN
THE 80S FOR THE PLAINS...AND 70S FOR THE HIGH VALLEYS. ISOLATED
CONVECTION IS EXPECTED TO LINGER OVER THE FAR SE CORNER AS WELL AS
THE SOUTHERN PORTIONS...INCLUDING THE S SANGRES.
THURSDAY AND FRIDAY...THE UPPER RIDGE BEGINS TO SLIDE TO THE
EAST...AS AN UPPER TROUGH OF LOW PRESSURE BEGINS TO MOVE ONSHORE
ALONG THE WEST COAST. THIS WILL START TO DRAW INCREASING MOISTURE UP
ACROSS THE 4 CORNERS AND INTO WESTERN CO...WHICH IN TURN INCREASES
POPS FOR THE MTS AND WESTERN AREAS FROM THU AFTN ONWARD. A SLIGHT
COOLING TREND IS EXPECTED FROM THU THROUGH FRI...THOUGH TEMPS WILL
STILL BE AT OR SLIGHTLY ABOVE SEASONAL NORMS.
SATURDAY AND SUNDAY...EXTENDED MODELS AGREE ON MOVING THE UPPER
TROUGH AXIS ACROSS THE PAC NW AND GREAT BASIN ON SAT...THROUGH THE
EC IS JUST A BIT SLOWER. THE TROUGH DEEPENS WITH A CLOSED LOW
DEVELOPING BY SUN...WHICH THEN SLOWLY MOVES EAST TOWARD COLORADO.
THE EC HAS THIS LOW OVER NV...WHILE THE GFS HAS THIS LOW EDGING
INTO THE WESTERN HALF OF COLORADO...SO STILL SOME ROOM FOR
NEGOTIATION THERE. END RESULT IS THAT A COOLER PERIOD WITH INCREASED
CLOUDS AND PCPN COVERAGE IS FORECAST FOR THE WEEKEND...AND THE FINER
POINTS AND TIMING WILL HAVE TO BE REVISITED THROUGHOUT THE UPCOMING
WORK WEEK. MOORE
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1104 PM MDT SUN SEP 21 2014
KALS...THERE SHOULD BE AN INCREASE IN SHOWER AND THUNDERSTORM
ACTIVITY OVER THE SAN JUAN MOUNTAINS TONIGHT WHICH MAY MOVE INTO
THE SAN LUIS VALLEY THROUGH MONDAY MORNING. IF ONE OF THESE CELLS
MOVES OVER THE TERMINAL...IT COULD PRODUCE REDUCED VIS AND CIGS.
DO EXPECT CIGS TO FALL BY 08Z TONIGHT WITH MVFR TO IFR CONDITIONS
INTO MONDAY MORNING. IMPROVING CONDITIONS ARE FORECAST BY MONDAY
AFTERNOON.
KCOS AND KPUB...LIGHT EAST TO SOUTHEASTERLY FLOW WILL KEEP
MOISTURE IN PLACE ACROSS THE TERMINALS TONIGHT WHICH WILL LEAD TO
LOWERED CIGS...ESPECIALLY AT KCOS WHERE THEY WILL LIKELY FALL TO
MVFR TO IFR TONIGHT. THERE REMAINS UNCERTAINTY ON SHOWER ACTIVITY
TONIGHT...AS MODELS ARE OVER DOING IT RIGHT NOW...BUT LEFT VCSH IN
THE FORECAST TO ACCOUNT FOR THIS UNCERTAINTY. THERE IS ALSO THE
POSSIBILITY FOR STRONG THUNDERSTORMS AT KCOS AND KPUB MONDAY
AFTERNOON. HAIL AND GUSTY OUTFLOW WINDS ARE POSSIBLE WITH STRONGER
STORMS. MOZLEY
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...MOZLEY
SHORT TERM...HODANISH
LONG TERM...MOORE
AVIATION...MOZLEY
AREA FORECAST DISCUSSION
NWS TAUNTON MA
145 AM EDT MON SEP 22 2014
.SYNOPSIS...
A PERIOD OF STEADY RAIN WILL AFFECT THE FAR SOUTHEAST NEW ENGLAND
COAST THIS EVENING. OTHERWISE...DRIER AND LESS HUMID WEATHER IS
ON TAP FOR MONDAY AS A DRY COLD FRONT SWEEPS ACROSS THE REGION.
STRONG HIGH PRESSURE WILL BRING SUNNY DAYS AND CLEAR NIGHTS TO THE
REGION FROM TUESDAY THROUGH NEXT WEEKEND WITH A WARMING TREND. WE
COULD APPROACH RECORD WARMTH ON SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
130 AM UPDATE...
OVER THE LAST HOUR OR TWO...WINDS HAVE SHIFTED TO THE W AS
ISALLOBARIC COUPLET SUPPORTS RAPID PRES RISES TO THE W AND FALLING
TO THE E AS LOW PRES SLIDES TOWARD NOVA SCOTIA. THIS SHIFT HAS
LEAD TO A DRYING TREND AND REDUCTION IN THE OVERALL FOG COVERAGE.
WILL MAINTAIN CURRENT SPS/S AND ADVISORIES FOR THE TIME BEING
THOUGH AS THE ACTUAL FRONT IS NOW ONLY JUST E OF THE CT VALLEY
AND WILL TAKE 3-6 MORE HOURS TO CLEAR. OTHERWISE...FORECAST MAINLY
ON TRACK AS REMNANT SHOWERS CONTINUE TO DRY AS THEY REACH THE
DOWNSLOPING IN THE E SLOPES OF THE BERKSHIRES.
PREVIOUS DISCUSSION...
MARGINAL INSTABILITY WITH DEEP LOW LEVEL MOISTURE HAS ALLOWED
ISOLATED TO SCATTERED SHOWERS TO CONTINUED TO AFFECT SOUTHERN NEW
ENGLAND. WE SHOULD SEE THIS ACTIVITY DIMINISH EARLY THIS EVENING
WITH THE LOSS OF DAYTIME HEATING.
THE MAIN CONCERN WILL BE THE SURFACE LOW PRESSURE SYSTEM OFF THE MID
ATLANTIC COAST WHICH WILL BE TRACKING NORTHEAST AND PASSING NEAR THE
BENCHMARK THIS EVENING. THE MAIN QUESTION IS HOW FAR NORTHWEST
THE RAIN SHIELD WILL GET. LATEST NEAR TERM GUIDANCE HAS BEEN
TRENDING FURTHER NORTHWEST. THEREFORE...EXPECT A PERIOD OF STEADY
RAIN ACROSS THE CAPE/ISLANDS AND PROBABLY FURTHER NORTHWEST INTO
INTERIOR SOUTHEAST MA/RHODE ISLAND FOR AT LEAST A TIME. IN
FACT...LATEST HRRR SHOWING THE POTENTIAL FOR A BRIEF PERIOD OF
RAIN ACROSS THE NORTHEAST MA COAST INCLUDING BOSTON. NOT SURE IF
IT WILL GET THAT FAR NORTHWEST...BUT ITS CERTAINLY POSSIBLE.
REGARDLESS...THE HEAVIEST RAINFALL WILL OCCUR ACROSS NANTUCKET...
WHERE BETWEEN 0.50 TO PERHAPS UP TO 1 INCH OF RAIN MAY OCCUR.
THE RAIN MAY PERSIST THROUGH MUCH OF THE EVENING ACROSS THE CAPE
AND ISLANDS...BUT SHOULD WIND DOWN NEAR OR JUST AFTER MIDNIGHT.
MEANWHILE...ONCE THE ISOLATED TO SCATTERED DIURNALLY DRIVEN
SCATTERED SHOWERS WIND DOWN EARLY THIS EVENING...THE REST OF THE
REGION WILL MAINLY BE DRY TONIGHT. HOWEVER...A COLD FRONT WILL BE
APPROACHING OUR WESTERN ZONES TOWARD MIDNIGHT. WHILE SHEAR IS QUITE
IMPRESSIVE...VERY LITTLE INSTABILITY WILL BE LEFT. SO WHILE WE MAY
SEE A FEW SPOT SHOWERS AFFECT OUR WESTERN ZONES...THEY WILL BE IN
THE PROCESS OF WEAKENING AND NOT EXPECTING MUCH MORE THAN THAT. LOW
TEMPS WILL ONLY BOTTOM OUT IN THE UPPER 50S AND THE LOWER 60S BY
DAYBREAK MONDAY.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TUESDAY/...
MONDAY...
A MUCH DRIER AIRMASS WILL WORK INTO THE REGION BEHIND
THE COLD FRONT ON MONDAY. WHILE PARTLY TO MOSTLY SUNNY SKIES ARE
EXPECTED EARLY...MAY SEE A SCATTERED TO BROKEN DECK OF STRATO-
CUMULUS CLOUDS WORK INTO AT LEAST THE INTERIOR BY AFTERNOON. HIGHS
SHOULD MAINLY BE IN THE 60S ACROSS THE INTERIOR...BUT STILL WILL
REACH BETWEEN 70 AND 75 ALONG HE COASTAL PLAIN. GUSTY WEST WINDS
OF 20 TO 30 MPH ARE EXPECTED AS BUFKIT SOUNDINGS SHOWING VERY GOOD
MIXING.
HIGH SURF...GIVEN LARGE SOUTH TO SOUTHEAST SWELL FROM DEPARTING
COASTAL LOW PRESSURE SYSTEM HAVE ISSUED A HIGH SURF ADVISORY FOR THE
SOUTH COAST ON MONDAY. WE ISSUE HIGH SURF PRODUCTS THROUGH THE END
OF SEPTEMBER IF CONDITIONS WARRANT.
MONDAY NIGHT...
HIGH PRESSURE WILL BE BUILDING IN FROM THE WEST. THIS WILL ALLOW
FOR DIMINISHING WINDS AND SKIES TO BECOME MOSTLY CLEAR. LOOKS LIKE
A PRETTY GOOD NIGHT OF RADIATIONAL COOLING...WITH LOWS BOTTOMING OUT
IN THE UPPER 30S TO THE MIDDLE 40S IN MOST LOCALES. THE URBAN HEAT
ISLAND OF BOSTON WILL BE THE MILD SPOT WITH THE LOW BOTTOMING OUT
NEAR 50.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
HIGHLIGHTS...
* HIGH PRESSURE AND DRY WEATHER THROUGH THE PERIOD
* NEAR RECORD WARMTH POSSIBLE NEXT SATURDAY
OVERVIEW...
VERY GOOD AGREEMENT AMONGST MODEL GUIDANCE THE ENTIRE FORECAST
PERIOD. AN UPPER LEVEL TROUGH DEPARTS THE NORTHEAST STATES ON
TUESDAY. THEN...MUCH ADO ABOUT BUILDING HIGH PRESSURE...BOTH AT
THE SURFACE AND ALOFT THE REMAINDER OF THE WEEK. THE UPPER RIDGE
IS VERY STRONG AS IT IS PARKED FROM THE GREAT LAKES TO SOUTHERN
NEW ENGLAND BY NEXT WEEKEND.
DETAILS... TUESDAY WILL FEATURE MOSTLY SUNNY SKIES EXCEPT ONLY
PARTLY SUNNY NW MA AND SW NH CLOSER TO SOME HIGHER 925 MB
HUMIDITY. OTHERWISE...EXPECT SUNNY DAYS AND CLEAR NIGHTS THROUGH
NEXT WEEKEND. HAVE GONE A FEW DEGREES LOWER THAN MODEL CONSENSUS
TEMPERATURE MINIMUMS THROUGH THU DUE TO EXCELLENT RADIATIONAL
COOLING EXPECTED ALONG WITH VERY DRY DEWPOINTS. AS THE CENTER OF
THE UPPER HIGH APPROACHES...AM EXPECTING A DRAMATIC WARMUP FRI
AND ESPECIALLY SAT. THE 12Z ECMWF RUN IS EVEN WARMER THAN THE
PREVIOUS RUN WITH 925 MB TEMPERATURES WARMING FROM +12C TUE...TO
+17C FRI... TO +19C OR +20C ON SAT... WITH WARM TEMPERATURES
LIKELY CONTINUING INTO EARLY THE FOLLOWING WEEK. HAVE GONE SEVERAL
DEGREES ABOVE MODEL CONSENSUS MAXIMUMS FOR NEXT SATURDAY...WITH
HIGHS SOARING TO 80 TO 85 ACROSS INTERIOR SOUTHERN NEW ENGLAND.
RECORDS FOR THAT DAY INCLUDE 85 AT WORCESTER AND 86 AT BOTH BOSTON
AND PROVIDENCE.
LIGHT WINDS ARE EXPECTED FOR THE PERIOD...SO ALTHOUGH IT WILL BE
DRY WE ARE NOT EXPECTING FIRE WEATHER CONCERNS. LOCAL SEA BREEZES
WILL OCCUR...ESPECIALLY FRI THROUGH NEXT SUNDAY. IT SHOULD BE
NOTED THAT THE GFS HAS A HINT OF A POTENTIAL BACKDOOR FRONT/TROUGH
OVER NORTHEAST MA ON SAT BUT THIS WAS NOT ENOUGH TO DETRACT FROM
THE VERY WARM FORECAST...AS YET.
AN UPPER LOW OVER VIRGINIA AND AN ASSOCIATED INVERTED TROUGH IS
LIKELY TO BE CAUSING PRECIPITATION IN THE MID ATLANTIC REGION
MID TO LATE IN THE WORK WEEK THAT TRIES TO WORK ITS WAY NORTHWARD.
THERE IS EXCELLENT MODEL AGREEMENT THAT THIS AREA ONLY GETS AS
FAR NORTHWARD AS OFF THE NJ COAST BY FRI...BEFORE RETREATING
SOUTHWARD AS STRONG HIGH PRESSURE BECOMES ESTABLISHED OVER THE
NORTHEAST ON THE WEEKEND.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY/...
THROUGH 12Z...HIGH CONFIDENCE IN TRENDS...LOWER CONFIDENCE IN
TIMING.
WITH A MIX OF ALL CATEGORIES...EXPECT THE GENERAL TREND THROUGH
12Z WILL BE TOWARD VFR FROM W-E. TIMING IN TAFS MAY BE OFF BY AN
HOUR OR SO...BUT ONCE WINDS PICK UP AND SHIFT MORE W-NW VFR SHOULD
DOMINATE THEREAFTER.
TODAY INTO TUESDAY...HIGH CONFIDENCE.
VFR...ALTHOUGH MVFR/IFR CONDITIONS MAY LINGER AT ACK THROUGH MID
MORNING. WINDS MAINLY WNW TODAY...GUSTING TO AROUND 25 KT AT
TIMES THEN DIMINISHING OVERNIGHT.
KBOS TERMINAL...HIGH CONFIDENCE FOR MAINLY VFR FROM NOW ON.
KBDL TERMINAL...HIGH CONFIDENCE FOR MAINLY VFR FROM NOW ON.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...
HIGH CONFIDENCE.
TUE...VFR.
WED...VFR
THU...VFR.
FRI...VFR.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
TONIGHT...MODERATE TO HIGH CONFIDENCE. LOW PRESSURE PASSING NEAR
THE BENCHMARK WILL RESULT IN ENOUGH SOUTH TO SOUTHEAST SWELL FOR
SCA SEAS TO DEVELOP ACROSS THE OUTER-WATERS AND WESTERN SOUNDS.
SOUTHEAST WINDS SHOULD BECOME SOUTHWEST TONIGHT AT 10 TO 15 KNOTS
LATER TONIGHT. AREAS OF FOG...SOME LOCALLY DENSE...WILL OCCUR
ACROSS THE WATERS...ESPECIALLY SOUTH OF BOSTON HARBOR.
MONDAY AND MONDAY NIGHT...MODERATE TO HIGH CONFIDENCE. SCA SEAS
ON THE WESTERN SOUNDS AND OUTER-WATERS WILL CONTINUE THROUGH
MONDAY NIGHT. IN ADDITION...A PERIOD OF WEST TO NORTHWEST WIND
GUSTS NEAR 25 KNOTS IS POSSIBLE FOR A TIME ON MONDAY.
THEREFORE...IT IS POSSIBLE WE MAY NEED TO EXPAND SCA FOR A TIME
DURING THE DAY MONDAY INTO SOME OF THE NEARSHORE SOUNDS AND
WATERS. CONFIDENCE NOT QUITE HIGH ENOUGH TO DO THIS RIGHT NOW...
SO WILL DEFER TO THE NEXT SHIFT.
OUTLOOK...TUESDAY THROUGH FRIDAY...
HIGH CONFIDENCE...
TUE AND WED...SEAS NEAR 5 FT MAY LINGER AT TIMES TUE AND WED OVER
THE WATERS S AND E OF NANTUCKET. OTHERWISE WINDS AND SEAS SHOULD
BE BELOW SMALL CRAFT ADVISORY CRITERIA. A NORTHEAST WIND GRADIENT
WILL INCREASE OVER THE SOUTHERN COASTAL WATERS TUE NIGHT INTO WED
AS STRONG HIGH PRESSURE PUSHES INTO NORTHERN NEW ENGLAND. BUT
GUSTS ARE EXPECTED TO ONLY REACH 20 KT.
WED NIGHT THROUGH FRI...QUIET BOATING WEATHER WITH HIGH PRESSURE
DOMINATING THE WEATHER. WINDS AND SEAS BELOW SCA THRESHOLDS.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...HIGH SURF ADVISORY FROM 8 AM THIS MORNING TO 5 PM EDT THIS
AFTERNOON FOR MAZ020>024.
DENSE FOG ADVISORY UNTIL 5 AM EDT EARLY THIS MORNING FOR
MAZ006-007-014.
NH...NONE.
RI...HIGH SURF ADVISORY FROM 8 AM THIS MORNING TO 5 PM EDT THIS
AFTERNOON FOR RIZ006>008.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 AM EDT TUESDAY FOR ANZ235-237.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT TUESDAY FOR ANZ250-254>256.
SMALL CRAFT ADVISORY FROM 6 AM THIS MORNING TO 4 PM EDT THIS
AFTERNOON FOR ANZ251.
&&
$$
SYNOPSIS...FRANK/GAF
NEAR TERM...FRANK/DOODY/GAF
SHORT TERM...FRANK
LONG TERM...GAF
AVIATION...DOODY/GAF
MARINE...FRANK/GAF
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
138 AM EDT MON SEP 22 2014
.PREV DISCUSSION... /ISSUED 1008 PM EDT SUN SEP 21 2014/
UPDATE...
CONVECTION CONTINUES TO SLIDE SOUTHWARD ACROSS NORTH GEORGIA AND
THERE IS SOME UNCERTAINTY IN HOW THE PRECIP WILL PLAY OUT LATE
TONIGHT INTO MONDAY. OVERALL HAVE CHOSEN TO SHOW IT CONTINUING TO
SINK SOUTHWARD...BUT DECREASE THE COVERAGE FROM SCATTERED TO
ISOLATED OVERNIGHT. HRRR EXPANDS AREA OF PRECIP BY 14Z WHILE THE
LOCAL WRF ISNT QUITE THAT BOLD. CONSIDERING HRRR HAS BEEN OVERDONE
THIS SUMMER OVERALL...HAVE LEANED MORE TOWARDS THE LOCAL WRF. POP
GRIDS MAY STILL BE A TAD UNDERDONE THOUGH FOR LATE TONIGHT INTO
MONDAY.
MADE A SLIGHT INCREASE IN POPS ACROSS THE FAR SOUTHEAST PART OF
THE CWA FOR MONDAY AFTERNOON AS VORT MAX MAY HELP TO INCREASE
CONVECTION.
PREV DISCUSSION...
SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
/ISSUED 317 PM EDT SUN SEP 21 2014/
COLD FRONT IS PUSHING INTO THE TENNESSEE VALLEY AT AFD TIME WITH
ISOLATED SHOWERS DEVELOPING ALONG AND JUST AHEAD OF IT. CAPE VALUES
ARE ON THE LOW END...GENERALLY BELOW 1500 J/KG ACROSS NORTH
GEORGIA...AND BEST PVA IS ACTUALLY BEHIND THE FRONT AND DOES NOT
PUSH INTO GEORGIA REALLY UNTIL MONDAY SOMETIME. SO HAVE KEPT TREND
OF SLIGHT TO LOW CHANCE POPS WITH WORDING LIMITED TO ONLY SLIGHT
CHANCE THUNDER...ESPECIALLY SINCE WHAT CAPE MIGHT BE AROUND THIS
AFTERNOON QUICKLY DECREASES OVERNIGHT. DRY AIR STARTS FILTERING INTO
NORTH GEORGIA BEHIND THE FRONT BUT NEW RUNS ARE A LITTLE SLOWER WITH
THIS SO LOW TEMPS TONIGHT NOT FORECAST QUITE AS COOL AS WITH EARLIER
FORECASTS.
CONVECTION SHOULD FIRE ACROSS CENTRAL GEORGIA MONDAY AFTERNOON AND
WITH A PRETTY STRONG VORT LOBE SWINGING AROUND WITH THE SHARP TROUGH
ALOFT...EXPECT TO SEE A LITTLE MORE CONVECTIVE DEVELOPMENT THEN.
MUCAPES INCREASE TO BETWEEN 800-1500 J/KG ACROSS CENTRAL GEORGIA
TOMORROW DEPENDING ON WHICH MODEL ONE USES /NAM IS HIGHER AS USUAL/.
STILL HAVE LOW TO MID-RANGE CHANCE POPS AT BEST BUT WILL HAVE TO
REEVALUATE THIS OVERNIGHT.
DEEP-LAYER CAA BEHIND THE FRONT IS PRETTY IMPRESSIVE ESPECIALLY
EARLY TOMORROW ACROSS NORTH GEORGIA...THOUGH THE CAA MODERATES EVER
SO SLIGHTLY IN THE AFTERNOON. SHOULD SEE A MARKED DIFFERENCE IN
TEMPERATURES BEHIND THE FRONT TOMORROW /5-10 DEGREES COOLER EXCEPT
ACROSS SOUTHERN ZONES WHERE THE FRONT WILL NOT HAVE QUITE MADE IT
THROUGH YET/ AND ESPECIALLY TOMORROW NIGHT /ANOTHER 5-10 DEGREES
COOLER THAN TONIGHT AGAIN EXCEPT FOR SOUTHERN ZONES/. THE DECREASE
IN HUMIDITY WILL ALSO BE VERY NOTICEABLE. ENJOY THE BEAUTIFUL FALL
WEATHER!
TDP
LONG TERM /TUESDAY THROUGH SUNDAY/...
/ISSUED 317 PM EDT SUN SEP 21 2014/
HIGH PRESSURE AND COOLER TEMPERATURES WILL DOMINATE MUCH OF THE
EXTENDED FORECAST PERIOD.
HIGH PRESSURE SITUATED ACROSS THE CENTRAL OHIO VALLEY ON TUESDAY
WILL SLOWLY SHIFT EASTWARD THROUGH THE WEEK. PROLONGED EASTERLY FLOW
OFF OF THE ATLANTIC WILL HELP INCREASE THE CLOUD COVER BY WEDNESDAY.
IN ADDITION...THE OLD FRONTAL BOUNDARY ACROSS NORTH-CENTRAL FLORIDA
WILL BEGIN TO PUSH NORTHWARD AS A WARM FRONT BY LATE WEDNESDAY INTO
EARLY THURSDAY. ISENTROPIC LIFT WILL BEGIN TO INCREASE ACROSS THE
SOUTHEAST ZONES BY THE END OF THE WEEK AND SPREAD W THROUGH THE
WEEKEND. INSTABILITY LOOKS MINIMAL...BUT AN ISOLD THUNDERSTORM
CANNOT BE RULED OUT.
NLISTEMAA
&&
.AVIATION...
06Z UPDATE...
STILL SOME SCATTERED SHRA ALONG FRONT TO DEAL WITH FOR THE NEXT
FEW HOURS SO WILL EXTEND TEMPO WITH THIS TAF SET. STRONG UPPER
LEVEL SYSTEM SWINGS THROUGH THIS AFTERNOON BUT DRIER AIR SHOULD
PRECLUDE ADDITIONAL SHRA DEVELOPMENT AND WILL KEEP ATL AREA
TERMINALS RAIN FREE FOR THIS AFTERNOON. MCN WILL NOT BE SO LUCKY
WITH NOT ONLY BETTER SHRA POTENTIAL BUT TSRA AS WELL AND WILL KEEP
PROB30 FOR THEM THROUGH THE AFTERNOON HOURS. OTHERWISE...CIGS
EXPECTED TO REMAIN VFR THROUGH THE PERIOD.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM ON SHRA POTENTIAL THIS AFTERNOON.
HIGH ON REMAINING ELEMENTS.
DEESE
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 81 56 79 55 / 20 0 0 0
ATLANTA 80 57 79 57 / 20 0 0 0
BLAIRSVILLE 74 48 76 51 / 5 0 0 0
CARTERSVILLE 78 52 80 55 / 5 0 0 0
COLUMBUS 84 59 83 61 / 20 0 0 0
GAINESVILLE 77 55 77 55 / 5 0 0 0
MACON 85 58 83 59 / 30 0 0 0
ROME 79 50 81 54 / 0 0 0 0
PEACHTREE CITY 80 52 80 55 / 20 0 0 0
VIDALIA 88 64 83 61 / 40 30 10 10
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...DEESE
LONG TERM....BDL
AVIATION...DEESE
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
315 AM EDT MON SEP 22 2014
.SYNOPSIS...
ISSUED AT 316 AM EDT MON SEP 22 2014
A PLEASANT START TO FALL AS HIGH PRESSURE OVER THE CENTRAL PLAINS
WILL BUILDS EASTWARD ACROSS THE OHIO VALLEY RESULTING IN MOSTLY
CLEAR AND DRY CONDITIONS. TEMPERATURES WILL MODERATE THROUGH THE
WEEK WITH HIGHS IN THE LOW 60S TODAY WARMING TO THE MID TO UPPER
70S BY FRIDAY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 316 AM EDT MON SEP 22 2014
PLAINS SFC RIDGE WILL INTENSIFY EWD THROUGH THE SRN LAKES/OH VALLEY
THIS PD MARKING THE START OF AN EXCEPTIONAL PD OF PLEASANT WEATHER.
HWVR LL THERMAL TROUGH WILL HOLD FIRM YET TDA. COOL START AND
NEUTRAL ADVTN ALOFT WITHIN CONTD NRLY SFC GRADIENT FLW WILL SUBDUE
AFTN DIURNAL...ALTHOUGH THAT WILL NOT BE THE CASE ON TUE. CLR SKIES
AND DECOUPLING UNDERNEATH SFC RIDGE WARRANTS CUTTING MIN TEMPS SE
THIRD OVERNIGHT.
&&
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 316 AM EDT MON SEP 22 2014
DEEP TROUGH WILL REMAIN ANCHORED NEAR OR JUST OFF THE WEST COAST
RESULTING IN A LOT OF RIDGING ACROSS THE EASTERN HALF TO TWO THIRDS
OF THE CONUS. A WEAK DISTURBANCE ATTEMPTS TO PASS NEAR THE WESTERN
GREAT LAKES THURSDAY BUT WILL HIT A BRICK WALL AND EITHER BE SHEARED
OUT OR SHIFTED WELL NORTH OF THE AREA. THE RESULT IS A CONTINUED DRY
FORECAST WITH SUNNY TO MOSTLY SUNNY DAYS AND GENERALLY CLEAR NIGHTS.
ECMWF IS ADVERTISING A SLUG OF TROPICAL MSTR WORKING NORTH WITH A
DISTURBANCE. EVEN IF THIS COMES TO FRUITION...NO WORRIES UNTIL MAYBE
MONDAY AT THE EARLIEST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 222 AM EDT MON SEP 22 2014
EVOLUTION OF WRN BOUND OF MOIST LL CYCLONIC FLW NR TERM PROBLEMATIC
GIVEN LL THERMAL INVERSION IN PLACE AND AS YET STILL DEEP NRLY
TRAJECTORY NOTED IN PBL. THUS EXTENSIVE MVFR STRATOCU SHIELD ACRS MI
MAY CONT TO WRAP SWD AS SHOWN IN LATEST RAP MODEL GUIDANCE AS
OPPOSED TO MOST OTHER 00Z BASED GUIDANCE WHICH CARRIES IT EWD OF THE
TERMINALS THIS MORNING. HWVR TRIED TO KEEP SOME CONTINUITY W/PRIOR
FCST BUT OF WHICH MIGHT BE TOO OPTIMISTIC. WILL MONITOR AND AMEND AS
NECESSARY.
OTRWS RIDGING SFC AND ALOFT BLDG THROUGH OH VALLEY AND BREAKDOWN OF
LL THERMAL TROUGH PREDICATES VFR CONDS AND LIGHT WINDS FOR THE
REMAINDER OF THE WEEK.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR LMZ043-
046.
&&
$$
SYNOPSIS...NG
SHORT TERM...T
LONG TERM...FISHER
AVIATION...T
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
223 AM EDT MON SEP 22 2014
.SYNOPSIS...
ISSUED AT 740 PM EDT SUN SEP 21 2014
COOLER CONDITIONS ARE EXPECTED TONIGHT ACROSS THE REGION AS A COLD
FRONT PUSHES SOUTHEAST OF THE AREA. ASIDE FROM SOME CLOUD COVER
OVERNIGHT...DRY CONDITIONS AND MOSTLY CLEAR SKIES ARE EXPECTED
AFTER TONIGHT THROUGH THE ENTIRE WORK WEEK. TEMPERATURES WILL
GRADUALLY WARM FROM HIGHS IN THE LOW 60S MONDAY TO HIGHS IN THE
MID TO UPPER 70S BY FRIDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 352 PM EDT SUN SEP 21 2014
THE FORECAST CHALLENGES INCLUDE ENDING OF SHOWERS EARLY TONIGHT AND
AMOUNT OF CLEARING OVERNIGHT. A SHORT WAVE TROF WAS MOVING ACROSS
LOWER MICHIGAN INTO NORTHERN INDIANA THIS AFTERNOON. A SECONDARY
COLD FRONT WAS ASSOCIATED WITH THIS SYSTEM FROM NORTHEAST ILLINOIS
INTO SOUTHWEST LOWER MICHIGAN. VERY COLD AIR ALOFT IN ADDITION TO
THE UPPER TROF AND COLD FRONT WERE SUFFICIENT TO PRODUCE SHOWERS.
KEPT A MENTION OF ISOLATED THUNDER LATE THIS AFTERNOON OVER
NORTHEAST GIVEN THE INSTABILITY WITH COLD AIR ALOFT. THERE WERE A
FEW LIGHTNING STRIKES OVER SOUTHEAST LOWER MICHIGAN NORTH OF
INTERSTATE 94 DURING THE MIDDLE OF THIS AFTERNOON. SKIES SHOULD
BEGIN TO CLEAR BEHIND THE FRONT EARLY TONIGHT. SOME CONCERN FOR LAKE
CLOUDS FORMING UNDER THE BASE OF A DEVELOPING INVERSION OVERNIGHT.
ADDED SOME LAKE CLOUDS TONIGHT GIVEN A FAVORABLE FETCH AND
INCREASING DELTA T VALUES. OTHERWISE...TEMPERATURES WILL BE CHILLY
WITH LOWS AWAY FROM ANY LINGERING AREAS OF LAKE CLOUDS WELL DOWN
INTO THE 40S. KEPT TEMPERATURES MUCH BELOW NORMAL MONDAY WITH HIGHS
AROUND 60S MOST AREAS.
&&
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 352 PM EDT SUN SEP 21 2014
VERY LITTLE TO DISCUSS WITH RESPECT TO SENSIBLE WEATHER IN THE LONG
TERM PERIOD. HIGH PRESSURE WILL BE ENTRENCHED OVER THE REGION
THROUGH THE PERIOD. TEMPERATURES WILL SLOWLY MODERATE...TRENDING
FROM BELOW NORMAL TO ABOVE NORMAL BY END OF PERIOD. IT SHOULD REMAIN
DRY THROUGH THE END OF THE WEEK AND LIKELY DRY THROUGH NEXT WEEKEND.
MODELS DO BEGIN TO SHOW AN INCREASE IN MOISTURE NEXT WEEKEND IN
RESPONSE TO SOME TROPICAL MOISTURE WORKING TOWARD THE AREA WITH WEAK
UPPER LOW UNDERCUTTING RIDGE. NO SUPPORT FOR ADDING POPS WITH LACK
OF ANY STRONG UPPER AIR SUPPORT OR SFC TRIGGER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 222 AM EDT MON SEP 22 2014
EVOLUTION OF WRN BOUND OF MOIST LL CYCLONIC FLW NR TERM PROBLEMATIC
GIVEN LL THERMAL INVERSION IN PLACE AND AS YET STILL DEEP NRLY
TRAJECTORY NOTED IN PBL. THUS EXTENSIVE MVFR STRATOCU SHIELD ACRS MI
MAY CONT TO WRAP SWD AS SHOWN IN LATEST RAP MODEL GUIDANCE AS
OPPOSED TO MOST OTHER 00Z BASED GUIDANCE WHICH CARRIES IT EWD OF THE
TERMINALS THIS MORNING. HWVR TRIED TO KEEP SOME CONTINUITY W/PRIOR
FCST BUT OF WHICH MIGHT BE TOO OPTIMISTIC. WILL MONITOR AND AMEND AS
NECESSARY.
OTRWS RIDGING SFC AND ALOFT BLDG THROUGH OH VALLEY AND BREAKDOWN OF
LL THERMAL TROUGH PREDICATES VFR CONDS AND LIGHT WINDS FOR THE
REMAINDER OF THE WEEK.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 1 PM EDT THIS AFTERNOON FOR LMZ043-
046.
&&
$$
SYNOPSIS...NG
SHORT TERM...SKIPPER
LONG TERM...LASHLEY
AVIATION...T
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1220 AM CDT MON SEP 22 2014
.UPDATE...
ISSUED AT 1220 AM CDT MON SEP 22 2014
UPDATED FOR THE NEW 06Z AVIATION DISCUSSION.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 301 PM CDT SUN SEP 21 2014
MOST OF THE CLOUDS HAVE DISSIPATED ACROSS THE CWA THIS
AFTERNOON...WITH A RIBBON OF THICKER CLOUDS REMAINING JUST WEST OF
THE NORTHLAND. THE RAP HAS BEEN CONSISTENT ON BRINGING SOME OF
THESE CLOUDS BACK INTO OUR WESTERN/NORTHERN ZONES TONIGHT. THERE
IS SOME EASTWARD MOVEMENT TOWARD KOOCHICHING COUNTY OVER THE LAST
SEVERAL SATELLITE IMAGES. WE HAVE DO BRING AN INCREASE IN CLOUDS
OVER PARTS OF THE WEST/NORTH TONIGHT.
HIGH PRESSURE WILL KEEP THE CWA DRY THROUGH MONDAY WITH MORE SUN
EXPECTED.
LOWS TONIGHT WILL DROP INTO THE UPPER THIRTIES TO LOWER FORTIES.
WE WENT ON THE LOW END OF GUIDANCE AND EVEN DROPPED TEMPS A BIT
MORE OVER PARTS OF OUR FAR NORTHEAST ZONES AND FROM KHYR TO KPBH.
LATER SHIFTS WILL HAVE TO MONITOR TEMPS CLOSELY AS IF THEY DROP A
BIT MORE THAN EXPECTED...SOME PATCHY FROST IS POSSIBLE. FOG WILL
ALSO BE POSSIBLE TONIGHT.
HIGHS MONDAY WILL BE SEVERAL DEGREES ABOVE NORMAL...AND RANGE FORM
THE MID SIXTIES TO AROUND SEVENTY.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 301 PM CDT SUN SEP 21 2014
DRY CONDITIONS EXPECTED EARLY IN THE WEEK WITH AN UPPER LEVEL RIDGE
BUILDING EWD ACROSS THE UPPER MIDWEST/WRN GREAT LAKES AREA. AT THE
SFC A 1025MB HIGH WILL TRANSLATE EWD THROUGH THE SRN GREAT LAKES. A
SLY FLOW WILL DEVELOP BEHIND THE DEPARTING HIGH AND AHEAD OF THE
NEXT INCOMING AREA OF LOW PRESSURE. THIS NEXT SYSTEM WILL TRACK FROM
THE ROCKIES THROUGH THE CENTRAL PLAINS DURING THE DAY TUESDAY. THE
MAIN FORCING WILL REMAIN ALOFT ASSOCIATED WITH THE UPPER LOW...WHICH
WILL RUN INTO A BLOCKING HIGH TO THE EAST AND LIFT TO THE NE THROUGH
NRN MN AND WRN LAKE SUPERIOR LATE TUE NIGHT AND THROUGH THE DAY WED.
RAIN SHOWERS WILL ACCOMPANY THIS SYSTEM...AND REMAIN CONFINED TO
AREAS NORTH OF MN HIGHWAY 210 AND EWD ALONG THE SOUTH SHORE IN NW
WI. RAINFALL AMTS ARE EXPECTED TO BE LIGHT. A BROAD HIGH AMPLITUDE
RE-ENFORCING UPPER LEVEL RIDGE IS EXPECTED TO BUILD THROUGH THE
CENTRAL U.S. ON THURSDAY...AND INTO THE GREAT LAKES BY FRIDAY. THIS
HIGH PRESSURE WILL KEEP CONDITIONS DRY AND WARM THROUGH FRIDAY AND
INTO THE WEEKEND. TEMPERATURES THROUGH THE WEEK WILL REMAIN
RELATIVELY WARM WITH HIGHS IN THE UPPER 60S AND 70S...AND OVERNIGHT
LOWS IN THE 50S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1220 AM CDT MON SEP 22 2014
VFR IS EXPECTED THROUGH MUCH OF THE FORECAST. THE EXCEPTION WILL BE
WHEN BR FORMS AND VSBYS DROP INTO THE MVFR RANGE. SOME CU POSSIBLE
AFTER 13Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 48 70 51 68 / 0 0 10 20
INL 45 74 52 69 / 0 0 10 30
BRD 47 72 54 70 / 0 0 30 20
HYR 44 73 50 69 / 0 0 0 10
ASX 47 72 51 69 / 0 0 0 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...MELDE
LONG TERM...BJT
AVIATION...GROCHOCINSKI
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
436 AM EDT MON SEP 22 2014
.SYNOPSIS...
A LARGE AREA OF HIGH PRESSURE OVER THE NORTHERN AND CENTRAL PLAINS
WILL SETTLE OVER THE OHIO VALLEY TONIGHT AND TUESDAY. HIGH
PRESSURE IS THEN FORECAST TO EXTEND ACROSS THE REGION THROUGH THE
END OF THE WEEK. TEMPERATURES WILL START OUT COOL EARLY THIS
WEEK...FOLLOWED BY A WARMING TREND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LARGE SCALE MID LEVEL TROUGH OVER THE EASTERN GREAT LAKES THIS
MORNING WILL SHIFT EAST INTO NEW ENGLAND AND EASTERN CANADA
THROUGH TODAY. AS THIS OCCURS...A SPRAWLING AREA OF SURFACE HIGH
PRESSURE OVER THE NORTHERN AND CENTRAL PLAINS WILL MOVE/BUILD
SOUTHEAST INTO OUR REGION. MAIN FORECAST DILEMMA TODAY WILL BE
FIGURING OUT THE COVERAGE OF CAA STRATOCUMULUS AND HOW FAST THEY
WILL EXIT THE AREA. HAVE USED THE RAP MODEL AS A GUIDE TO FIGURE
THIS OUT WHICH KEEPS ROUGHLY THE EASTERN TWO THIRDS MOSTLY CLOUDY
THROUGH MID MORNING FOLLOWED BY CLEARING SKIES AS SUBSIDENCE...DRYING
AND ANTICYCLONIC FLOW INCREASE FROM THE WEST. TEMPERATURES WILL BE
BELOW NORMAL FOR THE ARRIVAL OF AUTUMN WITH HIGHS RANGING FROM THE
LOWER TO MID 60S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
SURFACE HIGH PRESSURE WILL SETTLE OVER THE OHIO VALLEY TONIGHT.
CLEAR SKIES...LIGHT TO CALM WINDS...AND A DRY AIRMASS WILL MAKE
FOR FAVORABLE RADIATIONAL COOLING CONDITIONS. HAVE USED A BLEND OF
THE ADJUSTED MAV GUIDANCE AND CONSENSUS RAW 2 METER TEMPERATURES
TO TRY TO CAPTURE THE NORMALLY COOL SPOTS. LOWS WILL RANGE FROM
THE UPPER 30S IN THOSE COOL SPOTS TO THE MID 40S AT RIDGE TOPS AND
NEAR URBAN AREAS.
THE HIGH WILL REMAIN IN PLACE ON TUESDAY. SUNNY SKIES AND A
MODIFYING AIRMASS WILL ALLOW TEMPERATURES TO WARM INTO THE UPPER
60S TO THE LOWER 70S.
A MID LEVEL RIDGE WILL BUILD INTO THE GREAT LAKES AND MIDDLE OHIO
VALLEY TUESDAY NIGHT INTO WEDNESDAY. AT THE SAME TIME...SURFACE
HIGH PRESSURE WILL EXTEND FROM NEW ENGLAND INTO THE OHIO VALLEY.
LITTLE IF ANY CLOUD COVER IS EXPECTED THROUGH THE PERIOD. A
WARMING TREND WILL CONTINUE DUE TO A WARMING/MODIFYING AIRMASS.
DIURNAL SWINGS OF 25 TO 30 DEGREES WILL BE LIKELY GIVEN THE DRY
AIRMASS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
MID/UPPER LEVEL RIDGING WILL REMAIN IN CONTROL THROUGH THE LONG TERM
PERIOD. THE MODELS ARE HINTING AT SOME MOISTURE POSSIBLY TRYING TO
WORK UP FROM THE SOUTH HEADING INTO THE WEEKEND...BUT WITH RIDGING
OVERHEAD...WILL MAINTAIN A DRY FORECAST. TEMPERATURES WILL
CONTINUE TO SLOWLY WARM AS THE AIRMASS CONTINUES TO MODIFY/WARM THROUGH
THE END OF THE WEEK. TEMPERATURES THROUGH THIS PERIOD SHOULD RUN
A FEW DEGREES ABOVE NORMAL.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
AN EXPANSE OF STRATOCUMULUS CLOUDS IS CURRENTLY IN PLACE OVER
SOUTHERN MICHIGAN AND NORTHERN OHIO...AND THESE CLOUDS ARE
GRADUALLY MAKING PROGRESS TO FILL IN AND MOVE FURTHER SOUTH. THESE
CLOUDS ARE GENERALLY IN THE 2500-4000 FOOT RANGE...AND SOME
PERIODS OF MVFR CEILINGS WILL BE POSSIBLE...ESPECIALLY AT THE
CENTRAL OHIO TAF SITES. NNW WINDS HAVE GENERALLY SUBSIDED TO
AROUND 10 KNOTS...BUT GUSTS TO 20 KNOTS WILL STILL BE POSSIBLE FOR
ANOTHER FEW HOURS IN CENTRAL OHIO.
THESE CLOUDS WILL GRADUALLY DISSIPATE DURING THE MORNING
HOURS...AS WINDS SETTLE IN AT AROUND 10 KNOTS THROUGH THE
AFTERNOON. WITH HIGH PRESSURE MOVING INTO THE AREA...CLEAR SKIES
AND LIGHT WINDS WILL PERSIST INTO THE OVERNIGHT HOURS AND THROUGH
TUESDAY.
OUTLOOK...NO SIGNIFICANT WEATHER IS EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HICKMAN
NEAR TERM...HICKMAN
SHORT TERM...HICKMAN
LONG TERM...JGL/HICKMAN
AVIATION...HATZOS
AREA FORECAST DISCUSSION
NWS PORTLAND OR
906 PM PDT SUN SEP 21 2014
.SYNOPSIS..A DYING FRONT MAY HOLD TOGETHER ENOUGH TO BRING A FEW
SHOWERS TO THE COAST MONDAY NIGHT...THEN FURTHER INLAND TUESDAY. A
MORE ORGANIZED SYSTEM WILL BRING MORE WIDESPREAD RAIN MIDWEEK...WITH
COOL AND SHOWERY WEATHER AFTERWARDS. AFTER A LONG HOT SUMMER...AUTUMN
WEATHER WILL BE ARRIVING RIGHT ON TIME.
&&
.EVENING UPDATE...A CLUSTER OF SHOWERS AND THUNDERSTORMS DEVELOPED
OVER KLAMATH AND DESCHUTES COUNTIES THIS AFTERNOON...AND HAVE SLOWLY
PROGRESSED NORTHWESTWARD INTO EASTERN LANE COUNTY THIS EVENING. IT
SEEMS STORMS ARE BEGINNING TO FINALLY TREND WEAKER...BUT
ADMITTEDLY...IT SEEMS JUST WHEN WE BEGIN THINKING THIS...A NEW
UPDRAFT GOES UP AND TEMPORARILY INVIGORATES AN EXISTING OR NEW STORM.
THE PRIMARY THREAT WITH THESE STORMS WILL BE BRIEF HEAVY RAIN AND AN
OCCASIONAL CLOUD TO GROUND LIGHTNING STRIKE. THE LATTER HAS
DEFINITELY BEEN TRENDING LESS OVER THE LAST HOUR. SUSPECT THESE
STORMS WILL WEAKEN FURTHER AS THEY ENTER EASTERN LINN COUNTY.
GLOBAL TO HIGH RESOLUTION SHORT TERM MODELS HAVE NOT BEEN
PARTICULARLY HELPFUL THIS EVENING. TO VARYING DEGREES THOUGH...LOWER
RESOLUTION MODELS DO PRODUCE SOME LIGHT QPF OVER THE CASCADES TONIGHT
INTO WEDNESDAY MORNING. THE RAP ALSO INDICATES THE STORMS ACROSS
EASTERN LANE COUNTY ARE FORMING IN A LOCALIZED REGION OF NEGATIVE 700
TO 500MB THETA LAPSE RATES. THE RAP SUGGESTS THIS REGION OF NEGATIVE
THETA LAPSE RATES WILL GRADUALLY WEAKEN AS IT SHIFTS NORTHWARD ACROSS
THE CASCADES TONIGHT AND EVENTUALLY EAST OF THE CREST TOWARDS
MORNING. NONETHELESS...BANDS OF ALTOCUMULUS HAVE DEVELOPED OVER THE
COAST AND WILLAMETTE VALLEY THIS EVENING. WITH NO DISTINCT INCOMING
VORT MAX ON WATER VAPOR THIS EVENING...SUSPECT THIS ALTOCUMULUS WILL
STAY RELATIVELY SHALLOW...BUT I AM STILL NERVOUS THAT SOMETHING
MIGHT FIRE FURTHER WEST OVER THE FOOTHILLS OR EVEN THE WILLAMETTE
VALLEY TONIGHT. WILL CONTINUE TO KEEP PRECIP/THUNDER CHANCES OVER
THE CASCADES...AND LEAVE A MENTION OUT OF THE FORECAST FOR THE
WILLAMETTE VALLEY...BUT WILL BE MONITORING THE SITUATION CLOSELY.
NO CHANGES TO THE REST OF THE FORECAST. WEDNESDAY STILL LOOKS TO BE
THE WETTEST DAY OF THE WEEK. /NEUMAN
PREVIOUS DISCUSSION BELOW...
.SHORT TERM...TONIGHT THROUGH WEDNESDAY...TEMPERATURES ARE GENERALLY
DOWN A COUPLE DEGREES VERSUS THIS TIME SATURDAY...AS LIGHT ONSHORE
FLOW HAS REPLACED THE OFFSHORE FLOW OF YESTERDAY. THE MOST DRAMATIC
TEMPERATURE DROPS HAVE BEEN ALONG THE COAST...WHERE ONSHORE FLOW AND
LOW CLOUDS ARE RESULTING IN TEMPS 10-15 DEGREES F COOLER THAN THIS
TIME YESTERDAY.
THE MARINE LAYER IS IN THE PROCESS OF DEEPENING...AND WILL LIKELY
MAKE A SUBSTANTIAL INLAND PUSH OVERNIGHT TONIGHT. BY SUNRISE MONDAY
IT IS LIKELY MUCH OF THE FORECAST AREA WILL BE UNDER A BLANKET OF
STRATUS. THE LOW CLOUDS WILL TAKE A LITTLE WHILE TO RETREAT TO THE
COAST...PROBABLY SOMETIME AROUND MIDDAY OR SHORTLY THEREAFTER. THE
INCREASED CLOUD COVER COMBINED WITH 850 MB TEMPS 3-5 DEG C COOLER
THAN TODAY SHOULD LEAD TO MAX TEMPS IN THE MID TO UPPER 70S MONDAY
AND EVEN THAT MAY BE A LITTLE OPTIMISTIC.
THIS WILL BE THE BEGINNING OF A TREND AWAY FROM THE PERSISTENT VERY
WARM AND DRY WEATHER THIS SUMMER HAS BROUGHT. AFTER 21 DAYS OF TEMPS
90 DEGREES OR WARMER AT PDX...AND A RECORD 36 DAYS AT OR ABOVE 90
DEGREES IN EUGENE...IT MAY BE SOMEWHAT SAFE TO SAY WE HAVE SEEN THE
LAST SUCH HEAT OF THE SEASON. AS WE NEAR THE END OF SEPTEMBER...THE
DAYS ARE GETTING SHORTER...AND THE SUN IS GETTING LOWER IN THE SKY.
IT BECOMES RAPIDLY MORE DIFFICULT CLIMATOLOGICALLY TO ACHIEVE 90
DEGREES AS WE MOVE TOWARD OCTOBER.
AND THIS TRANSITION IS HAPPENING RIGHT ON CUE...AS THE AUTUMNAL
EQUINOX IS FAST APPROACHING - 723 PM PDT ON MON SEP 22. MONDAY
EVENING A LARGE UPPER LOW AND TROUGH WILL BE APPROACHING THE PAC NW
COAST...LIKELY TO BRING A SIGNIFICANT AMOUNT OF RAIN TO OUR DISTRICT
AS ITS ASSOCIATED FRONTAL SYSTEM SLOWLY MOVES SLOWLY ONSHORE TUE-WED.
18Z NAM CONTINUES TO SHOW SOME POTENTIAL FOR A DECENT COASTAL JET
SETUP ALONG THE COAST TUE EVENING...PERHAPS BRINGING SOME SOUTH WIND
GUSTS 40-50 MPH TO THE BEACHES AND HEADLANDS. THIS WOULD BE THE FIRST
SUCH EVENT OF THE SEASON. CURRENT FORECAST DOES NOT REFLECT THIS JUST
YET...AS THERE IS SOME POTENTIAL FOR ENERGY TO BE SPLITTING AS THE
FRONT MOVES ONSHORE. LOWER PRESSURE TO THE NORTH AND LOWER PRESSURE
TO THE SOUTH WOULD CUT DOWN ON THE POTENTIAL OF SOUTH TO NORTH
GRADIENTS TO DRIVE SUCH WIND GUSTS.
WOULD NOT BE SURPRISED TO SEE SOME LOCATIONS SEE 1-3 INCHES OF RAIN
OUT OF THIS EVENT TUE THROUGH WED...PARTICULARLY COAST AND COAST
RANGE. INLAND AREAS COULD SEE UPWARDS OF 0.50-1.00 INCH DEPENDING ON
HOW WAVES TRACK ALONG THE FRONTAL ZONE AS IT LUMBERS ONSHORE. IF RAIN
GETS HEAVY...IT COULD BE A CONCERN FOR DEBRIS FLOWS IN SOME OF OUR
HARDER HIT FIRE AREAS THESE PAST FEW WEEKS. WILL CONTINUE TO MONITOR
THIS POSSIBILITY AND OF COURSE PASS ALONG MORE INFORMATION AS WE
LEARN THE SEVERITY OF THESE BURN SCARS. WEAGLE
.LONG TERM...AFTER OUR SLOW-MOVING FRONT CLEARS THE REGION WEDNESDAY
EVENING...MODELS SHOW DECENT AGREEMENT THAT AN UPPER LEVEL TROUGH
WILL SETTLE OVER THE PACIFIC NORTHWEST. THIS WILL MEAN COOL AND
UNSETTLED WEATHER WITH PLENTY OF SHOWERS AROUND FOR THE REST OF THE
WEEK. IT MAY TAKE UNTIL NEXT WEEKEND FOR TEMPS TO REBOUND BACK TO
NORMAL...THOUGH BEYOND FRIDAY MODELS HAVE ALL SORTS OF DIFFERENT
IDEAS OF HOW TO HANDLE OUR PATTERN. BEST GUESS IS THAT SOME FLAT
RIDGING WILL ATTEMPT TO RETURN BY THE WEEKEND...FOLLOWED BY SOME
FRONTAL SYSTEMS ATTEMPTING TO CLIP THE PAC NW BY EARLY NEXT WEEK.
THIS BASED MORE ON PATTERN RECOGNITION THAN ANYTHING ELSE...SO
CONFIDENCE IN ANY PARTICULAR SOLUTION IS RATHER LOW STARTING NEXT
WEEKEND. WEAGLE
&&
.AVIATION...VFR CONDITIONS CONTINUE ACROSS THE INTERIOR UNDER SCT
TO BKN CIRRUS AND SOME SMOKE FROM NEARBY WILDLAND FIRES FORMING A
SCATTERED LAYER AROUND 5000 FT. STORMS IN EASTERN LANE COUNTY
WILL NOT AFFECT EUGENE TERMINAL. A DEEPENING MARINE LAYER WILL
PUSH LOW MVFR STRATUS INTO MUCH OF THE VALLEY BY AROUND 12Z MON.
AT THE COAST...IFR CIGS HAVE PUSHED BACK ONSHORE AND WILL REMAIN
THROUGH LATE MONDAY MORNING BEFORE RISING TO MVFR.
KPDX AND APPROACHES...VFR CONDITIONS THROUGH 11Z MON THEN
INCREASING CHANCES FOR MVFR CIGS AROUND 1500 FT AS MARINE LAYER
DEEPENS AND PUSHES INLAND. MVFR CIGS LIKELY BY 13Z MON...LASTING
THROUGH 17Z MON WITH IMPROVEMENT TO VFR CONDITIONS THEREAFTER.
BOWEN/CULLEN
&&
.MARINE...SOUTHERLY WINDS CONTINUE ACROSS THE WATERS AND HAVE
WEAKENED THIS EVENING AS ANTICIPATED WITH CURRENT GUSTS AROUND 15
KT. UPDATES THIS EVENING INCLUDED SLIGHT ADJUSTMENT OF WINDS
BASED ON BEGINNINGS OF THE 00Z NAM. STILL LOOKS LIKE CONDITIONS
WILL REMAIN BENIGN THROUGH MONDAY WITH WINDS PICKING UP A BIT
MONDAY NIGHT AS A WEAK FRONT MOVES ACROSS THE WATERS. BOTH WINDS
AND SEAS INCREASE TUESDAY WITH THE APPROACH OF A STRONGER SYSTEM
WITH SEAS BUILDING TO 10-15 FT AND AT LEAST SMALL CRAFT ADVISORY
WINDS.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...NONE.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
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 AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
339 AM CDT MON SEP 22 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 339 AM CDT MON SEP 22 2014
AT 3 AM...A 1026 MB SURFACE HIGH WAS CENTERED OVER EASTERN
NEBRASKA. WHILE THE AREA IS UNDER CLEAR SKIES...WE SAW A RAPID
INCREASE IN OUR RADAR RETURNS FROM NEAR LA CROSSE TO BETWEEN
22.02Z AND 22.04Z....AND THEY HAVE REMAINED OVER THOSE AREAS
THROUGHOUT THE NIGHT. WHILE SOME OF THIS WAS OUR NORMAL ANOMALOUS
PROPAGATION OF THE RADAR BEAM THAT WE SEE AS THE NOCTURNAL
INVERSION DEVELOPS...THE 30 TO 40 DBZ RETURNS ARE MIGRATORY BIRDS
THROUGH THE AREA. WE KNOW THIS BECAUSE THE CORRELATION
COEFFICIENTS ARE RUNNING BETWEEN 0.65 AND 0.9. WITH NO
PRECIPITATION IN THESE AREAS...THIS MEANS THAT THESE RADAR TARGETS
ARE BIOLOGICAL IN NATURE. WE KNOW IT IS MIGRATORY BIRDS BECAUSE OF
THE TIME OF YEAR AND THAT THE VAD WIND PROFILE IS SHOWING 30 TO
45 KNOT WINDS BETWEEN 2 AND 15K FEET. TYPICALLY IN THESE SYNOPTIC
SITUATIONS WE DO NOT GET THIS MANY WIND LEVELS ALOFT WITHOUT
CLOUDS. IN ADDITION THESE WIND SPEEDS ARE RUNNING ABOUT 15 TO 25
KNOTS HIGHER THAN WHAT SHOW UP IN THE SOUNDINGS. THIS ADDITIONAL
SPEED IS FROM THE MIGRATORY BIRDS. THE HIGHEST CONCENTRATION OF
BIRDS ARE RUNNING BETWEEN 2 AND 8K FEET.
BESIDES THE BIRDS TONIGHT...BEEN WATCHING THE SLOW DEVELOPMENT OF
FOG. DENSE FOG IS ALREADY REPORTED AT BOSCOBEL AND BLACK RIVER
FALLS. WITH LIGHT WINDS /LESS THAN 10 KNOTS/ UP TO 2500 FEET AND
OUR WEB CAM ALREADY SHOWING A LAYER OF STRATUS IN THE VALLEYS...WE
EXPECT TO SEE A CONTINUAL DEVELOPMENT OF AREAS TO WIDESPREAD FOG.
FOLLOWED THE 930 TO 10 AM CLIMATOLOGY WITH THE DISSIPATION OF
THIS FOG.
TONIGHT...LOOKS TO BE EVEN MORE FAVORABLE FOR THE DEVELOPMENT OF
FOG IN THE RIVER VALLEYS AND CENTRAL WISCONSIN WITH LIGHT WINDS
UP TO 25K FEET AND CLEAR SKIES. AS A RESULT...WENT WITH WIDESPREAD
DENSE FOG FROM 2-3 AM THROUGH 930-10 AM.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 339 AM CDT MON SEP 22 2014
TUESDAY NIGHT...THE 22.00Z MODELS ARE IN GOOD AGREEMENT THAT WEAK
850 MB MOISTURE TRANSPORT WILL DEVELOP ACROSS SOUTHEAST MINNESOTA
AND NORTHEAST IOWA AHEAD OF A TROUGH MOVING OUT OF THE PLAINS.
BUFKIT SOUNDINGS BETWEEN 06Z AND 12Z ARE SATURATED BETWEEN 5 AND
20K FEET AND THERE IS OMEGA BETWEEN 5 AND 10K FEET. THIS RESULTS
IN THE MODELS GENERATING SOME LIGHT RAIN ACROSS THIS AREA. SINCE
ALL OF DETERMINISTIC MODELS WERE IN AGREEMENT...ADDED A 15 TO
24 PERCENT CHANCE OF RAIN TO THE FORECAST.
FROM WEDNESDAY INTO WEDNESDAY NIGHT...SHOW THAT THE 500 MB SHORT
WAVE TROUGH SHEARS APART ACROSS THE AREA. ONE PART MOVES NORTH AND
IS ABSORBED BY THE POLAR JET STREAM. MEANWHILE THE SOUTHERN PIECE
MOVES SOUTHWEST AND FORMS A CLOSED 500 MB LOW. WHILE THERE IS
AGREEMENT THAT THIS WILL OCCUR. THERE ARE DIFFERENCES IN
PRECIPITATION. BOTH THE ECMWF AND CANADIAN PRODUCE PRECIPITATION
ACROSS THE FORECAST AREA. MEANWHILE THE GFS AND NAM KEEP THIS
PRECIPITATION ACROSS SOUTH CENTRAL MINNESOTA AND WESTERN IOWA.
SINCE ECMWF SOUNDINGS ARE NOT SHOWING MUCH LIFT CO-LOCATED WITH
THE MOISTURE...KEPT THE FORECAST AREA.
FOR THE REMAINDER OF THE FORECAST PERIOD /THURSDAY THROUGH
SUNDAY/...IT LOOKS DRY AS HIGH PRESSURE REMAINS LOCATED ACROSS
THE AREA. 850 MB TEMPERATURES ARE RUNNING 10 TO 14C WHICH IS ABOUT
2 STANDARD DEVIATIONS ABOVE NORMAL. THIS RESULT IN TEMPERATURES
ABOUT 10 DEGREES WARMER THAN NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1137 PM CDT SUN SEP 21 2014
VALLEY FOG FORMATION CONTINUES TO BE THE MAIN CONCERN. THE
TEMP/DEW POINT SPREAD AT 04Z WAS 5F...WHICH IS NOT QUITE OPTIMAL
FOR FOG FORMATION...BUT CERTAINLY NOT OUTSIDE THE RANGE WHERE FOG
CAN BE DISCOUNTED. THE WINDS AT KLSE ARE LIGHT AND WERE STARTING
TO SWING AROUND TO A FAVORABLE UP VALLEY FLOW OF EAST/SOUTHEAST.
NO SIGNS OF A HAZE LAYER FORMING OVER THE CITY YET...SO HAVE
PUSHED BACK THE TIMING OF THE FOG A LITTLE BIT BUT WITH THE 22.00Z
NAM CONTINUING TO SHOW SATURATION OCCURRING AND THE 22.03Z RAP NOW
SHOWING THIS AS WELL...STILL FEEL FAIRLY CONFIDENT THAT FOG WILL
DEVELOP. ONCE THIS DISSIPATES FRIDAY MORNING...VFR CONDITIONS WITH
LIGHT WINDS AS THE SURFACE HIGHS DRIFTS OVER THE AREA.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1137 PM CDT SUN SEP 21 2014
.SHORT TERM...(TONIGHT)
ISSUED AT 200 PM CDT SUN SEP 21 2014
THE VIGOROUS UPPER LEVEL SHORTWAVE TROUGH THAT BROUGHT THE
SHOWERS/STORMS TO THE REGION LAST NIGHT WAS TRACKING ACROSS THE
EASTERN GREAT LAKES EARLY THIS AFTERNOON. SFC FRONT EXTENDED
WESTWARD FROM SYSTEMS/S LOW...BACK ACROSS WI. ADD IN FAVORABLE LOW
LEVEL LAPSE RATES AND SPOTTY/SCATTERED SHOWERS CONTINUED ACROSS
CENTRAL-EASTERN WI.
THE BOUNDARY WILL SLIP SOUTH BY THE EVENING WITH HIGH PRESSURE
BUILDING INTO IA/MO OVERNIGHT. A LOT OF DIURNAL ELEMENTS TO THE
CURRENT CLOUD MASS ACROSS THE REGION...AND WITH THE LOSS OF DAYTIME
HEATING AND SINKING AIR ASSOCIATED WITH THE HIGH...EXPECT THESE
CLOUDS TO CLEAR QUICKLY THIS EVENING. COULD SEE SOME FOG IN THE
RIVER VALLEYS FOR MONDAY MORNING.
.LONG TERM...(MONDAY THROUGH SUNDAY)
ISSUED AT 200 PM CDT SUN SEP 21 2014
GFS/ECMWF/GEM ALL IN GOOD AGREEMENT WITH BUILDING A STRONG UPPER
LEVEL RIDGE ACROSS THE CENTRAL U.S. FOR MUCH OF THIS WEEK. ALL WANT
TO SLIP A SHORTWAVE TROUGH FROM THE WEST COAST INTO THE
CENTRAL/NORTHERN PLAINS TUE...THEN TRIES TO LIFT IT EAST/NORTHEAST
ACROSS THE UPPER MISSISSIPPI RIVER VALLEY. GEM/GFS SPLIT THE UPPER
LEVEL ENERGY...TAKING A PIECE NORTH OF THE AREA...AND HANGING A
SOUTHERN PIECE OVER THE PLAINS. ASSOCIATED SFC FRONT ISN/T OVERLY
CONVERGENT IN THE LATEST SOLUTIONS. SOME LOW LEVEL MOISTURE
TRANSPORT COULD HELP FUEL SOME SHOWERS. THE GFS/GEM AND EVEN THE NAM
WOULD HOLD ANY PCPN ACROSS MN...PUSHING INTO SOUTHERN CANADA. SOME
SHOWER CHANCES OVER IA AND WEST INTO THE PLAINS. PREVIOUS EC RUN
FAVORED KEEPING THE SHORTWAVE TOGETHER...THUS STRONGER AND MORE
CONVERGENT TOWARD THE SFC WITH THE FRONT. HOWEVER...THE 12Z RUN IS
NOW MORE INLINE WITH THE SPLITTING SOLUTION. WILL LEAN THIS WAY.
THE BIT OF SOUTHERN ENERGY COULD RETROGRADE TO THE WEST WHILE THE
UPPER RIDGE CONTINUES TO ASSERT ITSELF. A SFC HIGH SETS UP SHOP OVER
THE EASTERN GREAT LAKES...PUTTING THIS REGION UNDER SOUTHERLY FLOW.
TEMPS WILL WARM...WITH 850 MB TEMPS CLIMBING FROM AROUND 8 C ON
MONDAY TO 16 C FRI. NAEFS 850 MB TEMP ANOMALIES POINTING TO +2
ACROSS SOUTHERN CANADA FOR THU-SAT...BUT 0-1 LOCALLY. STILL...LOOKS
LIKE ABOVE NORMAL TEMPERATURES TOWARD THE END OF THE WEEK...AND
COULD BE A VERY MILD OKTOBERFEST FOR THOSE IN THE LA CROSSE AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1137 PM CDT SUN SEP 21 2014
VALLEY FOG FORMATION CONTINUES TO BE THE MAIN CONCERN. THE
TEMP/DEW POINT SPREAD AT 04Z WAS 5F...WHICH IS NOT QUITE OPTIMAL
FOR FOG FORMATION...BUT CERTAINLY NOT OUTSIDE THE RANGE WHERE FOG
CAN BE DISCOUNTED. THE WINDS AT KLSE ARE LIGHT AND WERE STARTING
TO SWING AROUND TO A FAVORABLE UP VALLEY FLOW OF EAST/SOUTHEAST.
NO SIGNS OF A HAZE LAYER FORMING OVER THE CITY YET...SO HAVE
PUSHED BACK THE TIMING OF THE FOG A LITTLE BIT BUT WITH THE 22.00Z
NAM CONTINUING TO SHOW SATURATION OCCURRING AND THE 22.03Z RAP NOW
SHOWING THIS AS WELL...STILL FEEL FAIRLY CONFIDENT THAT FOG WILL
DEVELOP. ONCE THIS DISSIPATES FRIDAY MORNING...VFR CONDITIONS WITH
LIGHT WINDS AS THE SURFACE HIGHS DRIFTS OVER THE AREA.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RIECK
LONG TERM....RIECK
AVIATION...04
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1154 PM MDT SUN SEP 21 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 330 PM MDT SUN SEP 21 2014
AFTERNOON SATELLITE IMAGES SHOW WELL-DEFINED LOW PRESSURE AREA
LIFTING NORTH/NORTHEAST ACROSS THE GREAT BASIN...WITH ARM OF
MOISTURE ASSOCIATED WITH WEAK SHORTWAVE EXTENDING TO ITS N AND E
ADVECTING INTO THE INTERMOUNTAIN WEST. SHOWERS WERE OBSERVED AT
KCAG EARLIER THIS AFTERNOON...AND KCYS/KGJX 88D RETURNS SUGGEST
THIS MOISTURE HAS MADE IT INTO THE SIERRA MADRES AND ADJACENT WRN
FOOTHILL LOCATIONS. 20Z SFC ANALYSIS SHOWS 1026MB ACROSS THE
DAKOTAS AND NEBRASKA WITH RETURN FLOW ALONG THE FRONT RANGE AND A
WELL DEFINED SFC TROF BANKED UP ALONG THE EAST SLOPES OF THE SNOWY
RANGE. LLVL CONVERGENCE ALONG THIS SFC TROF HAS COMBINED WITH 250+
J/KG OF SBCAPE AS ANALYZED FROM SPC MESOANALYSIS TO SPARK A COUPLE
OF POCKETS OF DEEPER CONVECTION IN THE VICINITY OF CENTENNIAL/
WOODS LANDING/ALBANY OVR THE PAST FEW HOURS. LOW CENTER WILL REACH
IDAHO BY LATE TONIGHT...WITH ARM OF MOISTURE ADVECTION CONTINUING
FROM SW TO NE INTO THE CWFA. HIGH CLOUDS HAVE ALREADY BEEN ON THE
INCREASE ACROSS THE AREA...BUT SHOULD SEE THESE LOWER AND THICKEN
OVERNIGHT. ASCENT ASSOCIATED WITH THE UPPER-LOW WILL INCREASE
TONIGHT...SO WILL SEE SHOWERS AND STORMS INCREASE ESPECIALLY ALONG
AND WEST OF THE LARAMIE RANGE AS WELL. HAVE ALSO ADDED SOME FOG TO
THE SRN LARAMIE RANGE PER LATEST HRRR OUTPUT. LIGHTNING WAS EVIDENT
ACROSS SW COLORADO LAST NIGHT...SO IT MAKES SENSE TO KEEP IT
TONIGHT UP HERE TONIGHT. 12Z MODEL OUTPUT HAS TRENDED SLOWER IN
SPREADING RAIN CHANCES OUT ONTO THE ERN PLAINS...WHICH WILL LIKELY
NOW HOLD OFF NOW UNTIL SOMETIME MONDAY MORNING.
UPPER LOW WOBBLES THRU THE COWBOY STATE ON MONDAY...WHICH WILL
EFFECTIVELY SHARPEN AND ENHANCE AFTERNOON CONVECTION ALONG THE
PREFRONTAL SFC TROF/PACIFIC FRONT. BEST CONVECTIVE CHANCES ON
MONDAY WILL BE TIED CLOSELY TO THE LOCATION OF THIS TROF...WHICH
WILL BE WEST OF THE LARAMIE RANGE IN THE MORNING BEFORE PUSHING
EAST OF THE LARAMIE RANGE MONDAY. PROGD INSTABILITY PARAMETERS
LOOK FAIRLY MEAGER...WITH SBCAPES TOPPING OUT AROUND 500 J/KG.
HOWEVER...WITH THE PROXIMITY OF THE UPPER WAVE COMBINED WITH
DAYTIME DESTABILIZATION...WOULD EXPECT PERHAPS SOME MORE ORGANIZED
CONVECTION FOR LOCATIONS EAST OF THE MOUNTAINS. SHOWER AND
THUNDERSTORM CHANCES WILL DECREASE SOME FROM WEST TO EAST MONDAY
NIGHT.
UPPER-LOW WILL DEPART DURING THE DAY ON TUESDAY...BRINGING
PRECIPITATION CHANCES TO AN END FROM WEST TO EAST. OTHERWISE...
TUESDAY WILL LIKELY TURN A BIT BREEZY AND WINDS TURN WEST BEHIND
THE DEPARTING PREFRONTAL SFC TROF/PACIFIC FRONT. WIND GUSTS OF 20
TO 35 MPH CAN BE EXPECTED DURING THE AFTERNOON. MONDAY WILL BE THE
COOLEST DAY OF THE WEEK AS CLOUD COVER PROHIBITS THE AMOUNT OF
INSOLATION. EVEN SO...EXPECT HIGH TEMPERATURES IN THE 70S/LOW 80S.
HIGHS WILL WARM ABOUT 5 DEGREES OR SO ON TUESDAY...YIELDING MID
70S TO MID 80S.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 330 PM MDT SUN SEP 21 2014
NOT A WHOLE LOT OF CHANGE IN THE MODEL GUIDANCE THROUGH THE FIRST
HALF OF THE EXTENDED PERIOD. SUBSTANTIAL RIDGE BUILDS OVER THE
INTERMOUNTAIN WEST ON WED AND THIS WILL CAUSE TEMPS TO RISE TO
AROUND 10 DEGREES ABOVE NORMAL ACROSS THE CWA. WINDS WILL BE LIGHT
ON WED WITH WEAK SFC GRADIENTS AND FLOW ALOFT. NOT MUCH CHANGE FOR
THURS EXCEPT THAT SOUTH-TO-SOUTHEAST WINDS WILL BE BREEZY DURING
THE AFTN ACROSS THE PLAINS DUE TO PRESSURE FALLS OVER MONTANA. THE
MODELS CONTINUE TO EXHIBIT DIFFERENCES AS WE HEAD INTO NEXT
WEEKEND. THE GFS IS YET AGAIN THE MOST PROGRESSIVE WITH THE
WESTERN UPPER TROUGH...MOVING ITS AXIS TO NEAR UTAH BY SAT.
WIDESPREAD PRECIP IS PROGGED BEHIND THE COLD FRONTAL PASSAGE ON
SAT NIGHT...SOME OF WHICH COULD BE SNOW OVER THE MTNS. THE ECMWF
SHOWS A CUTOFF OVER CALIFORNIA ON SAT WHICH WOULD SIGNIFICANTLY
DELAY A COOLDOWN AND IS A MUCH DRIER SOLN. WITH SUCH BIG
DIFFERENCES ALMOST A WEEK OUT DECIDED TO INCREASE CLOUD COVER ON
SAT BUT KEEP ONLY SLIGHT CHANCE POPS ON SAT NIGHT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY EVENING)
ISSUED AT 1153 PM MDT SUN SEP 21 2014
CURRENT RADAR SHOWS SHOWERS AND T-STORMS FOCUSED MAINLY OVER
THE COLORADO MOUNTAINS AT 06Z...WITH A BREAK IN THE ACTION OVER
SOUTHEAST WYOMING. EXPECT THE ACTIVITY OVER COLORADO TO STEADILY
MOVE TO THE NORTHEAST AND OVER THE MOUNTAINS OF SOUTHEAST WYO AFTER
08Z WITH DRY CONDITIONS EAST OF THE LARAMIE RANGE. VFR CONDITIONS
SHOULD PREVAIL AS THIS ACTIVITY IS EXPECTED TO REMAIN WEAK.
MODEL GUIDANCE CONTINUES TO SHOW SCT IFR STRATUS OVER KCYS AFTER
08Z IN SOUTH-SOUTHEAST UPSLOPE FLOW. IN ADDITION...WINDS AT MOST
SITES WILL INCREASE OVERNIGHT...WITH SPEEDS OF 10 TO 15 KTS LIKELY
THROUGH THE MORNING. GUSTS OF 20 TO 30 KTS WILL THEN BE POSSIBLE
THROUGH MONDAY AFTERNOON...WITH T-STORM COVERAGE TO INCREASE
ACROSS THE EASTERN PLAINS AND CONTINUING THRU THE EARLY EVENING.
&&
.FIRE WEATHER...
ISSUED AT 330 PM MDT SUN SEP 21 2014
SHOWER AND THUNDERSTORM CHANCES TO INCREASE TONIGHT AND MONDAY.
THIS WILL KEEP FIRE WEATHER CONCERNS MINIMAL THROUGH AT LEAST
TUESDAY. AN AREA OF LOW PRESSURE WILL BRING RELATIVELY GOOD CHANCES
OF WETTING RAINS TO THE DISTRICTS TONIGHT THROUGH MONDAY EVENING.
DO NOT ANTICIPATE SIGNIFICANT RAINFALL TOTALS...HOWEVER A FEW
TENTHS OF AN INCH WILL BE A POSSIBILITY IN THE HEAVIEST
SHOWERS/STORMS. DRIER AND WARMER CONDITIONS WILL RETURN TUE-FRI.
EVEN SO MINIMUM RELATIVE HUMIDITIES ARE STILL ONLY EXPECTED TO
BOTTOM OUT NEAR 20 PERCENT.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...HAHN
LONG TERM...FINCH
AVIATION...RJM
FIRE WEATHER...HAHN
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
851 AM MDT MON SEP 22 2014
.UPDATE...
ISSUED AT 841 AM MDT MON SEP 22 2014
ONLY MINOR CHANGES NEEDED AT THIS UPDATE TIME. FIRST BATCH OF
SHOWERS NOW MOVING ACROSS THE NORTHEAST PLAINS WITH GENERALLY
LIGHT RAINFALL AMOUNTS AND NO LIGHTNING BEING REPORTED. SECONDARY
BATCH NOW OVER NORTHWEST COLORADO WITH QUITE A BIT OF LIGHTNING
ASSOCIATED WITH UPPER TROF AND 60KT JET STREAK. THIS WILL ALL
PUSH ACROSS NORTHERN COLORADO THIS AFTERNOON AND EARLY EVENING
END WITH STRONGER THUNDERSTORMS POSSIBLE. STORMS SHOULD DIMINISH
RAPIDLY THIS EVENING AS SUBSIDENCE KICKS IN BEHIND TROF.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 452 AM MDT MON SEP 22 2014
TROUGH PASSING OVER COLORADO TODAY. MODELS ARE PRETTY GOOD WITH
THE TIMING OF THE TROUGH THOUGH THERE ARE SOME DISAGREEMENTS AS TO
THE PLACEMENT OF CONVECTION. NAM COMPARES WITH THE CURRENT PATTERN
PRETTY MISERABLY...GFS HAS TOO LITTLE THIS MORNING AND TOO MUCH
THIS EVENING. HRRR LOOKS PRETTY REASONABLE BRINGING THE UPSTREAM
BATCH OF SHOWERS OVER DENVER AT MIDDAY...THEN GENERATING ISOLATED
THUNDERSTORMS OVER THE MOUNTAINS AND NORTHERN PART OF THE PLAINS
IN THE MID TO LATE AFTERNOON AS THERE IS SLIGHT COOLING ALOFT
BEHIND THE TROUGH. WILL GENERALLY GO WITH THIS IDEA...THOUGH I
HAVE SOME RESERVATIONS ABOUT MOISTURE AVAILABILITY. PLAINS REMAIN
COOL AND DRY AND WHILE SOUTHERLY WINDS ARE INCREASING THERE IS NOT
BETTER MOISTURE AT THE SURFACE UNTIL YOU GET TO TEXAS. SO THE
MOISTURE WILL HAVE TO BE COMING WITH THE SHOWER BAND. THERE WILL
BE SOME OF THIS GOING ON...BUT MODEL FORECAST MOISTURE ON THE
PLAINS DURING THE DAY LOOKS OVERDONE.
MOISTURE UNCERTAINTY IMPACTS THE PROSPECTS FOR STRONG STORMS.
WIND PROFILE IN THE MODELS IS GOOD FOR SUPERCELLS ALONG AND BEHIND
THE TROUGH AXIS ON THE PLAINS THIS AFTERNOON...NAM HAS CAPES OF
1000-1500 J/KG WHICH WOULD PRESENT A DECENT THREAT OF SEVERE
WEATHER. BUT THIS IS WITH DEW POINTS IN THE MID 50S WHICH LOOKS
PRETTY UNLIKELY...ESPECIALLY IN THE AIR BEHIND THE TROUGH WHERE
ANY REMAINING SURFACE MOISTURE SHOULD BE MIXING OUT. THERE ALSO
MAY BE MORE OF A WIND SHIFT THAN THE MODELS ARE SHOWING AS A
DENVER CYCLONE BOUNDARY THAT GETS PICKED UP WITH THE TROUGH AXIS
AND MOVES EAST TURNING INTO A DRYLINE SEEMS QUITE POSSIBLE. NAM/GFS
MOS DEW POINTS OF 45-50 ONLY GIVE CAPES AROUND 500 J/KG...AND I
THINK THIS IS MORE LIKELY. GIVEN THE WIND PROFILE AND FAST MOVING
STORMS...MAYBE STILL A SMALL WIND THREAT.
FOR TONIGHT THERE MAY BE SOME SHALLOW CONVECTION IN LINGERING LIFT
IN THE NORTHERN PART OF THE AREA FOR A WHILE...BUT SUBSIDENCE AND
CLEARING SHOULD BE COVERING THE AREA BY MORNING. COULD BE A
MOUNTAIN WAVE SETUP WITH SOME WARMING ALOFT BY 12Z...THOUGH SPEEDS
ARE MARGINAL SO PROBABLY JUST A BIT GUSTIER THAN WOULD OTHERWISE
BE EXPECTED. WITH JUST A LITTLE COOLING ALOFT...SNOW LEVEL SHOULD
STAY ABOVE TIMBERLINE.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 452 AM MDT MON SEP 22 2014
TUESDAY AND TUESDAY NIGHT...THE STORM SYSTEM WILL PASS TO THE
NORTH AND EAST WITH A NORTHWESTERLY FLOW ALOFT OVER THE REGION.
ENOUGH MID LEVEL INSTBY AND MOISTURE WILL BE PRESENT FOR SOME
LINGERING SHOWERS/TSTMS IN THE HIGH COUNTRY AND FAR NORTHEAST
PLAINS THROUGH EARLY TUESDAY EVENING. WEDNESDAY THROUGH
THURSDAY...AN UPPER LEVEL RIDGE WILL BUILD OVER THE GREAT
BASIN/CENTRAL ROCKIES WITH A DRY AND SUBSIDENT NORTHERLY FLOW
ALOFT OVER NORTHEAST COLORADO. TEMPERATURES WILL CLIMB BACK INTO
THE MID TO UPPER 80S. BY FRIDAY...THE RIDGE AXIS IS PROGGED TO
SHIFT TO THE EAST WITH A WEAK SLY FLOW ALOFT OVER THE STATE.
SUBTROPICAL MOISTURE WILL START TO ADVECT BACK INTO COLORADO. SOME
POPS GET INTRODUCED BACK INTO THE HIGH COUNTRY BY FRIDAY
AFTN...WITH A BETTER CHANCE OF SHOWERS/TSTMS FOR THE REST OF
NORTHEAST AND NORTH CENTRAL COLORADO OVER THE WEEKEND AHEAD OF THE
NEXT UPPER TROUGH WHICH IS EXPECTED TO MOVE ACROSS NRN PORTIONS OF
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z TUESDAY MORNING)
ISSUED AT 841 AM MDT MON SEP 22 2014
AREA OF LIGHT RAIN NOW SPREADING NORTHEAST ACROSS APA/DEN SO HAVE
ADJUSTED LATEST TAFS FOR THESE TRENDS. SHOWERS WILL DIMINISH
BETWEEN 16-17Z WITH A BREAK IN THE PRECIP BEFORE NOON. EXPECT
SCATTERED THUNDERSTORMS TO DEVELOP THIS AFTERNOON AS UPPER TROF
MOVES OVER THE AREA ESPECIALLY GIVEN CURRENT THUNDERSTORMS NOW OVER
WESTERN CO.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ENTREKIN
SHORT TERM...GIMMESTAD
LONG TERM...COOPER
AVIATION...ENTREKIN
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
452 AM MDT MON SEP 22 2014
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 452 AM MDT MON SEP 22 2014
TROUGH PASSING OVER COLORADO TODAY. MODELS ARE PRETTY GOOD WITH
THE TIMING OF THE TROUGH THOUGH THERE ARE SOME DISAGREEMENTS AS TO
THE PLACEMENT OF CONVECTION. NAM COMPARES WITH THE CURRENT PATTERN
PRETTY MISERABLY...GFS HAS TOO LITTLE THIS MORNING AND TOO MUCH
THIS EVENING. HRRR LOOKS PRETTY REASONABLE BRINGING THE UPSTREAM
BATCH OF SHOWERS OVER DENVER AT MIDDAY...THEN GENERATING ISOLATED
THUNDERSTORMS OVER THE MOUNTAINS AND NORTHERN PART OF THE PLAINS
IN THE MID TO LATE AFTERNOON AS THERE IS SLIGHT COOLING ALOFT
BEHIND THE TROUGH. WILL GENERALLY GO WITH THIS IDEA...THOUGH I
HAVE SOME RESERVATIONS ABOUT MOISTURE AVAILABILITY. PLAINS REMAIN
COOL AND DRY AND WHILE SOUTHERLY WINDS ARE INCREASING THERE IS NOT
BETTER MOISTURE AT THE SURFACE UNTIL YOU GET TO TEXAS. SO THE
MOISTURE WILL HAVE TO BE COMING WITH THE SHOWER BAND. THERE WILL
BE SOME OF THIS GOING ON...BUT MODEL FORECAST MOISTURE ON THE
PLAINS DURING THE DAY LOOKS OVERDONE.
MOISTURE UNCERTAINTY IMPACTS THE PROSPECTS FOR STRONG STORMS.
WIND PROFILE IN THE MODELS IS GOOD FOR SUPERCELLS ALONG AND BEHIND
THE TROUGH AXIS ON THE PLAINS THIS AFTERNOON...NAM HAS CAPES OF
1000-1500 J/KG WHICH WOULD PRESENT A DECENT THREAT OF SEVERE
WEATHER. BUT THIS IS WITH DEW POINTS IN THE MID 50S WHICH LOOKS
PRETTY UNLIKELY...ESPECIALLY IN THE AIR BEHIND THE TROUGH WHERE
ANY REMAINING SURFACE MOISTURE SHOULD BE MIXING OUT. THERE ALSO
MAY BE MORE OF A WIND SHIFT THAN THE MODELS ARE SHOWING AS A
DENVER CYCLONE BOUNDARY THAT GETS PICKED UP WITH THE TROUGH AXIS
AND MOVES EAST TURNING INTO A DRYLINE SEEMS QUITE POSSIBLE. NAM/GFS
MOS DEW POINTS OF 45-50 ONLY GIVE CAPES AROUND 500 J/KG...AND I
THINK THIS IS MORE LIKELY. GIVEN THE WIND PROFILE AND FAST MOVING
STORMS...MAYBE STILL A SMALL WIND THREAT.
FOR TONIGHT THERE MAY BE SOME SHALLOW CONVECTION IN LINGERING LIFT
IN THE NORTHERN PART OF THE AREA FOR A WHILE...BUT SUBSIDENCE AND
CLEARING SHOULD BE COVERING THE AREA BY MORNING. COULD BE A
MOUNTAIN WAVE SETUP WITH SOME WARMING ALOFT BY 12Z...THOUGH SPEEDS
ARE MARGINAL SO PROBABLY JUST A BIT GUSTIER THAN WOULD OTHERWISE
BE EXPECTED. WITH JUST A LITTLE COOLING ALOFT...SNOW LEVEL SHOULD
STAY ABOVE TIMBERLINE.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 452 AM MDT MON SEP 22 2014
TUESDAY AND TUESDAY NIGHT...THE STORM SYSTEM WLL PASS TO THE
NORTH AND EAST WITH A NORTHWESTERLY FLOW ALOFT OVER THE REGION.
ENOUGH MID LEVEL INSTBY AND MOISTURE WILL BE PRESENT FOR SOME
LINGERING SHOWERS/TSTMS IN THE HIGH COUNTRY AND FAR NORTHEAST
PLAINS THROUGH EARLY TUESDAY EVENING. WEDNESDAY THROUGH
THURSDAY...AN UPPER LEVEL RIDGE WILL BUILD OVER THE GREAT
BASIN/CENTRAL ROCKIES WITH A DRY AND SUBSIDENT NORTHERLY FLOW
ALOFT OVER NORTHEAST COLORADO. TEMPERATURES WILL CLIMB BACK INTO
THE MID TO UPPER 80S. BY FRIDAY...THE RIDGE AXIS IS PROGGED TO
SHIFT TO THE EAST WITH A WEAK SLY FLOW ALOFT OVER THE STATE.
SUBTROPICAL MOISTURE WILL START TO ADVECT BACK INTO COLORADO. SOME
POPS GET INTRODUCED BACK INTO THE HIGH COUNTRY BY FRIDAY
AFTN...WITH A BETTER CHANCE OF SHOWERS/TSTMS FOR THE REST OF
NORTHEAST AND NORTH CENTRAL COLORADO OVER THE WEEKEND AHEAD OF THE
NEXT UPPER TROUGH WHICH IS EXPECTED TO MOVE ACROSS NRN PORTIONS OF
CA/NV BY SUNDAY.
&&
.AVIATION...(FOR THE TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 452 AM MDT MON SEP 22 2014
VFR CONDITIONS WILL PREVAIL THROUGH TONIGHT...THOUGH INSTRUMENT
APPROACHES TO KDEN MAY BE NEEDED AT TIMES AS SHOWERS MOVE THROUGH.
MOST LIKELY TIME FOR THIS IS BETWEEN 16Z AND 22Z. SOUTH WINDS THIS
MORNING WILL LIKELY SHIFT TO NORTH DURING THE MIDDLE OF THE DAY AS
A DENVER CYCLONE STRENGTHENS AND THEN SHIFTS EAST. THIS PATTERN
COULD BE DISRUPTED WITH WIND SHIFTS DUE TO SHOWER ACTIVITY
HOWEVER.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GIMMESTAD
LONG TERM...COOPER
AVIATION...GIMMESTAD
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
959 AM EDT MON SEP 22 2014
.UPDATE...
THE WEAKENING FRONTAL BOUNDARY OVER CENTRAL FLORIDA WILL DISSIPATE
AS ANOTHER COLD FRONT OVER GEORGIA AND ALABAMA DRIFTS SOUTHEAST OVER
THE REGION. AMPLE MOISTURE IN PLACE WILL PROVIDE AN ENVIRONMENT
CONDUCIVE FOR SCATTERED TO NUMEROUS SHOWERS AND STORMS LATER THIS
MORNING AND AFTERNOON. LATEST WATER VAPOR IMAGERY SHOWS A LOT OF
MOISTURE OVER CENTRAL FLORIDA AND THE 12Z SOUNDING IS INDICATING
CLOSE TO 2 INCHES OF PRECIPITABLE WATER WITH A VERY MOIST COLUMN
BELOW 500 MB. THERE HAS ONLY BEEN A FEW ISOLATED SHOWERS ACROSS THE
COASTLINE THIS MORNING. MOST OF THE CONVECTION HAS REMAINED WELL OFF
SHORE...BUT IS EXPECTED TO PUSH OVER THE COASTLINE LATER THIS
MORNING INTO THE AFTERNOON.
FOR THE REST OF TODAY WE WILL CONTINUE TO SEE SCATTERED TO NUMEROUS
SHOWERS AND A FEW THUNDERSTORMS DEVELOP IN THE DEEPER MOISTURE AND
MOVE EAST NORTHEAST AFFECTING MOST AREAS THROUGHOUT CENTRAL FLORIDA.
THE LATEST HRRR COMPOSITE RADAR FORECAST HAS THE LARGEST MASS OF
PRECIPITATION MOVING INLAND JUST SOUTH OF TAMPA BAY AROUND 17-18Z.
THIS CONVECTION SHOULD SHIFT EASTWARD DURING THE AFTERNOON AS THE
LOW LEVEL SOUTH SOUTHWEST FLOW PUSHES THEM INLAND. GRIDS LOOK ON
TRACK FOR NOW.
&&
.AVIATION...
WILL KEEP VFR CONDITIONS AT ALL TAF LOCATIONS FOR TODAY. A FEW
ISOLATED SHOWERS HAVE MADE THEIR WAY ONSHORE NEAR SRQ THIS MORNING
BUT CONDITIONS REMAINED VFR. WILL KEEP VCSH IN THE MORNING AND VCTS
DURING THE AFTERNOON HOURS. ANY MVFR TO IFR WOULD BE MOST LIKELY
WITH THE TSRA LATER IN THE DAY. CALM TO LIGHT VARIABLE WINDS BECOME
SOUTH TO SW LATER THIS MORNING.
&&
.MARINE...
A COLD FRONT OVER THE SOUTHEAST U.S. WILL MOVE SOUTH INTO THE
NORTHERN GULF WATERS TONIGHT AND THEN STALL ACROSS THE
CENTRAL/SOUTHERN WATERS TUESDAY THROUGH FRIDAY. WINDS AND SEAS WILL
INCREASE SOME AS HIGH PRESSURE BUILDS IN FROM THE NORTH DURING THE
WEEK WITH PERIODS OF EXERCISE CAUTION CRITERIA POSSIBLE. THE MAIN
HAZARDS WILL CONTINUE TO BE HIGHER WINDS AND SEAS IN THE VICINITY
OF SCATTERED TO NUMEROUS THUNDERSTORMS THROUGH THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 88 74 87 73 / 60 40 60 30
FMY 89 74 88 72 / 60 40 50 40
GIF 88 72 88 72 / 60 40 60 30
SRQ 87 73 86 73 / 60 40 60 40
BKV 88 68 88 68 / 60 40 60 30
SPG 86 75 86 75 / 60 40 60 30
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE/AVIATION...74/WYNN
MARINE...69/CLOSE
DECISION SUPPORT...18/FLEMING
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1045 AM CDT Mon Sep 22 2014
.UPDATE...
ISSUED AT 1045 AM CDT MON SEP 22 2014
The forecast generally looks on track today with just very minor
updates to sky grids over eastern IL where few to scattered
cumulus clouds from I-57 east, especially near IN/IL border per
NAM and RUC curule but still mostly sunny skies. Highs in the
upper 60s to around 70F with north winds 5-10 mph.
1028 mb high pressure over nw IL and northern MO late this morning to
settle over central IL tonight and continue fair weather with
temperatures a bit below normal. Temps currently in the upper 50s
and lower 60s should climb about another 10 degrees for highs in
the upper 60s to around 70F this afternoon. Coolest readings over
east central IL.
&&
.SHORT TERM...(Today)
ISSUED AT 341 AM CDT MON SEP 22 2014
High pressure centered over eastern Nebraska will move east into the
area today. This will bring clear skies, dry weather and light
winds. Even with lots of sunshine today, highs are only expected
to reach into the upper 60s to around 70 degrees. GFS MOS guidance
looks several degrees too warm, while the NAM is too cool.
&&
.LONG TERM...(Tonight through Sunday)
ISSUED AT 341 AM CDT MON SEP 22 2014
An extended period of quiet weather throughout the remainder of the
forecast with high pressure building into and remaining in control
of the Midwest. Surface ridge dominating much of the eastern half
of the CONUS and keeping the weather quiet and fair, with slowly
warming temps through the work week. Weak flow under the sfc high
becomes more southerly on Tuesday as the ridge axis shifts slightly
eastward. Warming trend continues with the thermal ridging over
the desert SW slowly advecting into the center of the country and
max temps are just above normals by Thursday. A weak trof brings
some precip to the Plains Wednesday, but the ridge remains in place
and dry air eroding the activity before impacting Central Illinois.
In the extended, the GFS pushes some minor precip into the extreme
SE with an oddly evolving upper pattern beyond day 6. ECMWF
remaining dry and energy aloft without significant flow seeming to
retrograde somewhat under a larger scale ridge. Keeping the
forecast dry for next weekend until the models become a little more
cohesive with their solutions under the pattern shift.
&&
.AVIATION...(For the 12Z TAFS through 12Z Tuesday morning)
ISSUED AT 605 AM CDT MON SEP 22 2014
VFR conditions will continue at all sites next 24 hours. With high
pressure moving into the area, skies will be clear next 24 hours with
light and variable winds.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...07
SHORT TERM...AUTEN
LONG TERM...HJS
AVIATION...AUTEN
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1026 AM CDT MON SEP 22 2014
.UPDATE...
ISSUED AT 1026 AM CDT MON SEP 22 2014
UPDATE TO THE FORECAST TO ACCOUNT FOR THE BAND OF LIGHT
RAIN SHOWERS CURRENTLY ACROSS NORTHEAST COLORADO...THIS BAND IS
LIFTING TO THE NORTHEAST AND WILL IMPACT SOUTHWEST NEBRASKA AND
THE EASTERN PANHANDLE OVER THE NEXT COUPLE HOURS. PREVIOUS
FORECAST HAD THIS HANDLED WELL...JUST MINOR REVISIONS WERE
IMPLEMENTED. THE 22.14Z RUC13 SEEMS TO BE HANDLING THE CURRENT
SITUATION WELL AND IS BEING BLENDED WITH THE PREVIOUS FORECAST
WHICH SUGGESTS A SLIGHT DELAY IN QPF OF AN HOUR OR TWO ACROSS
SOUTHWEST NEBRASKA. IN ADDITION...INSTABILITY IS SOMEWHAT LACKING
OVER THIS AREA...THUS SHOWERS SHOULD PREVAIL RATHER THAN STORMS
THIS MORNING...BUT THE MODEL INDICATES A GRADUAL INCREASE WITH THE
INSTABILITY PARAMETERS INTO THE AFTERNOON...THUNDER IS POSSIBLE
THEN.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 401 AM CDT MON SEP 22 2014
TODAY AND TONIGHT...A DEEPENING SFC TROF WILL ADVANCE SOUTHEAST INTO
WRN NEB TODAY AND TONIGHT. SFC WINDS ARE EXPECTED TO INCREASE TO 15
TO 25 MPH WITH GUSTS TO 35 MPH ACROSS NWRN ZONES. WINDS RELAX A BIT
TONIGHT BUT REMAIN STRONG OFF THE SFC. THE LATEST MODEL CONSENSUS
SUGGESTS CLUSTERS OF SHOWERS AND THUNDERSTORMS SHOULD BE UNDERWAY BY
21Z THIS AFTN AS AN UPPER LOW ACROSS IDAHO ADVANCES EAST TOWARD AND
INTO WRN SD TODAY AND TONIGHT.
THE SEVERE WEATHER POTENTIAL LOOKS LOW TODAY AND TONIGHT AS THE
BETTER INSTABILITY REMAINS OVER ERN COLO. THE MODEL CONSENSUS
SUGGESTS 1/4 TO 1/2 INCH OF RAIN TODAY AND TONIGHT ACROSS THE FCST
AREA BUT THERE IS CERTAINLY THE POTENTIAL FOR MORE GIVEN PWS
INCREASING TO 1.33 INCHES WHICH IS 200 PERCENT OF NORMAL. THE NAM
INDICATED HIGHER VALUES.
THE ONGOING CLOUD COVER ACROSS WRN NEB IS EXPECTED TO INCREASE AND
EXPAND EAST TODAY. SOME CLEARING MAY DEVELOP IN THE WEST LATE
TONIGHT. GIVEN THE HIGH MOISTURE AVAILABLE POPS ARE LIKELY SOUTH AND
EAST TONIGHT.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 401 AM CDT MON SEP 22 2014
THE PRIMARY FORECAST CONCERN WILL BE THUNDERSTORM CHANCES
TUESDAY...THEN WITH TEMPERATURES AND RAIN CHANCES WITH A
RETROGRADING UPPER LEVEL SYSTEM THROUGHOUT THIS WEEK.
TUESDAY...THE UPPER LEVEL LOW WILL BE PUSHING OUT OF THE ROCKY
MOUNTAINS AND INTO THE NORTHERN PLAINS. THE MODELS ARE IN GOOD
AGREEMENT WITH THE UPPER LOW CENTER MOVING ACROSS SOUTH DAKOTA
THROUGH THE DAY...WITH VARIOUS WEAK SHORTWAVE IMPULSES MOVING AROUND
THE SYSTEM.
SHOWERS AND POTENTIALLY A FEW ISOLATED THUNDERSTORMS SHOULD BE
EXITING THE FORECAST AREA TO THE EAST DURING THE MORNING HOURS. BY
AFTERNOON...A SURFACE TROUGH WILL MAKE ITS WAY ACROSS THE PANHANDLE
AND INTO WESTERN NEBRASKA. FORECAST SOUNDINGS SHOW LOCATIONS
GENERALLY WEST OF HIGHWAY 83 WILL MIX OUT AND WITH STEEP LOW LEVEL
AND MID LEVEL LAPSE RATES...CAPE VALUES INCREASE TO 1000-2000 J/KG
BY LATE AFTERNOON AND WITH THE STRONG WARMING...SURFACE BASED
CONVECTION IS LIKELY. THERE IS SOME DISCREPANCIES BETWEEN MODELS IN
TERMS OF DEEP LAYER SHEAR...AS THE GFS IS MUCH STRONGER...SUGGESTING
IN EXCESS OF 40KTS...WHILE THE NAM IS 20 TO 30KTS. EVEN WITH THE
LOWER SHEAR...IT SHOULD BE SUFFICIENT FOR AT LEAST A FEW STRONGER
STORMS LATER TUESDAY AFTERNOON. AREAS TO THE EAST WILL SEE COOLER
HIGHS...IN THE UPPER 60S AND LOW 70S DUE TO THE PRECIPITATION
EARLIER IN THE DAY AND ARE LOOKING TO STAY VERY CAPPED. THESE AREAS
WILL STILL SEE STORMS MOVE IN DURING THE EVENING AND OVERNIGHT
HOURS...BUT THEY SHOULD BECOME ELEVATED QUICKLY AND WITH A LACK OF
INSTABILITY WOULD EXPECT THUNDER TO DECREASE...BUT THERE WILL BE AT
LEAST A WEAK LOW LEVEL JET THAT COULD CONTINUE TO FEED THE STORMS
THROUGH THE NIGHT AS THEY MOVE EAST.
AT 12Z WEDNESDAY MORNING...THE MODELS HAVE MOVED THE UPPER LOW
CENTER OVER SOUTHEAST SOUTH DAKOTA AND NORTHEAST NEBRASKA...AND WITH
THE UPWARD FORCING SHIFTING TO THE EAST...PRECIPITATION SHOULD BE
CLOSE TO...IF NOT COMPLETELY FINISHED LOCALLY. FAIRLY STRONG
SUBSIDENCE BUILDS IN ACROSS THE FORECAST AREA THROUGH THE DAY
WEDNESDAY BEHIND THE UPPER LEVEL SYSTEM LEADS TO A DRY FORECAST.
WARMER AIR WILL BE ADVECTING INTO THE AREA DURING THE DAY AND WITH
THE DRY AIR IN PLACE AND PLENTY OF SUNSHINE...STRONG WARMING IS
EXPECTED WITH HIGHS IN THE 80S FOR THE WESTERN TWO-THIRDS OF THE
FORECAST AREA. WITH THE UPPER LOW REMAINING OVER EASTERN
NEBRASKA...THE EASTERN PARTS OF THE FORECAST AREA MAY SEE SOME
RESIDUAL CLOUD COVER AND WITH COOLER TEMPERATURES ALOFT...WILL SEE
COOLER TEMPERATURES WITH HIGHS LOOKING TO BE IN THE MID TO UPPER 70S.
BEYOND WEDNESDAY THERE BEGINS TO BE SLIGHT DIVERGENCE IN THE MODEL
SOLUTIONS IN TERMS OF THE UPPER LEVEL PATTERN. WHAT IS IN GOOD
AGREEMENT IS A DEEP LONGWAVE TROUGH MOVING INTO THE WESTERN
CONUS...WITH RIDGING BUILDING AHEAD OF IT INTO THE NORTHERN
PLAINS. WHAT IS STARTING TO GET PROBLEMATIC IS THE CURRENT SYSTEM
GETS STUCK UNDER THE LARGE RIDGE WHICH SPANS INTO THE EASTERN PART
OF THE COUNTRY AND STARTS TO RETROGRADE. THE DISCREPANCIES LIE
WITH HOW FAR WEST IT WILL MAKE IT. THE RIDGE TO THE WEST WILL KEEP
SOUTHERLY FLOW IN THE LOWER LEVELS...KEEPING LOW LEVEL MOISTURE
ACROSS THE FORECAST AREA WITH DEWPOINTS REMAINING IN THE UPPER 50S
AND 60S...WHILE WEAK AND MINI SHORTWAVES MAY MOVE ACROSS THE FORECAST
AREA AT TIMES LATER IN THE WEEK. THESE SMALL IMPULSES OF ENERGY
AREN/T LOOKING TO GENERATE ENOUGH LIFT AT THIS POINT TO PROVIDE A
NEED FOR RAIN IN THE FORECAST SO WILL KEEP A DRY FORECAST AT THIS
TIME. WHAT THIS WILL MEAN IS LIKELY COOLER TEMPERATURES FOR LATE
IN THE WEEK AS THE WARMER AIR WILL BE KEPT TO THE WEST AND NORTH
OF THE LOCAL AREA DUE TO THE INFLUENCE OF THE UPPER LEVEL SYSTEM.
THEN LOOKING INTO THE WEEKEND...OUT OF THE LONGWAVE TROUGH MOVING
ONTO THE WEST COAST...A LOW WILL CLOSE OFF AND SLOWLY MIGRATE
TOWARDS THE EAST. THERE IS DIFFERENCES WITH THE SPEED AS THE
OPERATIONAL GFS IS FASTER THAN THE ECMWF AS WELL AS THE GFS
ENSEMBLE MEAN. THE FASTER SOLUTION WOULD BRING CHANCES FOR SHOWERS
AND THUNDERSTORMS BY SUNDAY AFTERNOON...WHILE THE SLOWER WOULD
KEEP THINGS DRY INTO MONDAY. WILL BE KEEPING A CLOSE EYE ON THIS
SYSTEM AS TIME GETS CLOSER TO GET A BETTER HANDLE ON THE FORECAST
FOR THESE PERIODS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 624 AM CDT MON SEP 22 2014
AREAS OF SHOWERS AND SCATTERED THUNDERSTORMS ARE EXPECTED TO
DEVELOP ACROSS WRN NEB 18Z- 20Z AND MOVE EAST NORTHEAST THROUGH
NCNTL NEB LATE THIS AFTN AND TONIGHT. THIS ACTIVITY IS EXPECTED TO
EXITING THE FCST AREA TO THE EAST 06Z- 12Z TUESDAY MORNING. MVFR
CIGS MAY DEVELOP ALONG AND NEAR HIGHWAY 61 06Z-09Z TUESDAY MORNING
IN THE WAKE OF THE TSTMS.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JACOBS
SHORT TERM...CDC
LONG TERM...BROOKS
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
652 AM EDT MON SEP 22 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE AREA THIS MORNING BEFORE STALLING
OFFSHORE. AN UPPER LEVEL LOW WILL BRING A CHANCE FOR SOME SHOWERS
AND ISOLATED THUNDERSTORMS THIS AFTERNOON AND TONIGHT. COOLER AND
DRIER WEATHER IS EXPECTED ON TUESDAY. THE STALLED COLD FRONT
OFFSHORE WILL WAVER BACK TOWARDS THE COAST DURING THE MIDDLE AND
LATTER PART OF THE UPCOMING WEEK...BRINGING GOOD CHANCES FOR RAIN
AND BELOW NORMAL TEMPERATURES. A WARMING AND DRYING TREND IS
EXPECTED DURING THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 640 AM MONDAY...UPDATES THIS MORNING FOCUS ON THE CLUSTER OF
SHOWERS FALLING OUT OF A MID-LEVEL CLOUD DECK ACROSS THE PEE DEE
REGION OF SOUTH CAROLINA. 07Z HRRR BRINGS IT STEADILY EASTWARD OVER
THE NEXT FEW HOURS WITH VERY LIGHT RAINFALL AMOUNTS EXPECTED. A NEW
CLUSTER OF CONVECTION IS INDICATED TO DEVELOP IN THE SANTEE
RIVER/CHARLESTON VICINITY BETWEEN 3-5 PM THIS AFTERNOON AHEAD OF THE
UPPER LEVEL DISTURBANCE. THIS WILL PROBABLY BE UPRIGHT CONVECTION
DEVELOPING ALONG AND JUST NORTH OF THE SURFACE FRONT...WITH UPPER
LEVEL WINDS POTENTIALLY BLOWING LIGHT RAIN ANOTHER 30-50 MILES NORTH
OF THE STORMS. NO SIGNIFICANT CHANGES HAVE BEEN MADE TO TEMPS OR
WINDS. PREVIOUS DISCUSSION FROM 300 AM FOLLOWS...
A POTENTIALLY INTERESTING FORECAST IS IN STORE FOR THE EASTERN
CAROLINAS OVER THE NEXT 24 HOURS. A COLD FRONT CURRENTLY EXTENDING
ALONG THE EASTERN EDGE OF THE NC PIEDMONT INTO CENTRAL SOUTH
CAROLINA SHOULD PUSH OFF THE COAST BY MID MORNING WITH
NORTH-NORTHEAST SURFACE WINDS ALLOWING A DRY CANADIAN AIRMASS TO
BUILD SOUTHWARD. THIS IS A SHALLOW AIRMASS CHANGE...WITH WIND
DIRECTIONS REMAINING WEST OR WEST-SOUTHWESTERLY AT AND ABOVE THE 850
MB LEVEL. THE FRONT WILL PUSH OUT JUST BEYOND THE GULF STREAM
TONIGHT WITH STRENGTHENING LOW-LEVEL NORTHEAST FLOW DEVELOPING AS
SURFACE PRESSURES RISE ACROSS THE MID-ATLANTIC REGION WITH HIGH
PRESSURE BUILDING EASTWARD FROM THE MIDWEST. UP AT 500 MB AN UPPER
DISTURBANCE DESCENDING INTO THE SOUTHERN APPALACHIANS THIS AFTERNOON
IS EXPECTED TO CUT OFF TONIGHT OVER WESTERN SOUTH CAROLINA.
THERE ARE A COUPLE CONCERNS WITH THE FORECAST WITHOUT A CLEAR ANSWER
AT THIS EARLY HOUR. THE FIRST IS HOW MUCH MID-LEVEL CLOUD COVER
HANGS AROUND TODAY AND WHAT IMPACT DOES IT HAVE ON TEMPERATURES?
SATELLITE IMAGERY REVEALS A NARROW BAND OF THICK CLOUDS OVER CENTRAL
AL/GA...MATCHING UP QUITE WELL WITH ANALYZED 700 MB RH MODEL FIELDS.
BOTH THE 00Z NAM AND GFS ADVECT THIS MOISTURE ACROSS EASTERN SOUTH
CAROLINA TODAY...LEADING ME TO BELIEVE THERE WILL BE TOO MUCH CLOUD
COVER TO LET TEMPERATURES RISE ABOVE THE LOWER 80S. IN FACT MORE
SUNSHINE UP IN THE LUMBERTON/ELIZABETHTOWN AREA WILL PROBABLY
BALANCE OUT THE OVERALL COOLER AIRMASS TO PRODUCE LOWER 80S ACROSS
THE ENTIRE FORECAST AREA TODAY.
THE SECOND CONCERN IS WITH THE UPPER LOW CUTTING OFF TO OUR WEST
TONIGHT HOW MUCH OVERRUNNING RAIN DEVELOPS? ISENTROPIC LIFT IS
ANTICIPATED TO REMAIN WELL ABOVE THE FRONTAL INVERSION...PROBABLY
NOT BEGINNING IN EARNEST UNTIL THE 310K THETA SURFACE WHICH WILL BE
UP NEAR 600 MB. THE 00Z GFS IS THE MOST AGGRESSIVE WITH BRINGING
RAIN ACROSS EASTERN SC LATE THIS AFTERNOON INTO TONIGHT. GIVEN THE
RELATIVELY WEAK WIND FIELDS PROGGED TO EXIST BELOW 600 MB IT IS HARD
TO BELIEVE THERE WILL BE SIGNIFICANT ADVECTION OF CONVECTIVE SHOWERS
ONSHORE EITHER. MY HIGHEST POP FORECASTS ARE LIMITED TO COASTAL
SOUTH CAROLINA IN THE 40-50 PERCENT RANGE...WITH 15-30 PERCENT
CHANCES ELSEWHERE.
CLOUDS WILL INHIBIT RADIATIONAL COOLING TONIGHT...HOWEVER INCREASING
NORTHEAST WINDS WILL ADVECT IN SIGNIFICANTLY COOLER AIR LEADING TO
LOWS FALLING INTO THE UPPER 50S FROM ELIZABETHTOWN THROUGH DILLON
AND DARLINGTON. LOWER 60S ARE EXPECTED ALONG THE COAST...EXCEPT FOR
SOME MID 60S ALONG THE COAST NEAR SOUTHPORT AND GEORGETOWN.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 AM MONDAY...THE FIRST FULL OF DAY OF FALL ON TUESDAY
BEGINS WITH COLD FRONT POSITIONED JUST OFFSHORE...AS LARGE CANADIAN
HIGH PRESSURE CENTERED OVER THE OH VLY RIDGES DOWN INTO THE
CAROLINAS. ALTHOUGH THIS FRONT WILL BE OFFSHORE...THERE IS SOME
UNCERTAINTY INTO JUST HOW FAR FROM THE COAST IT WILL GET BEFORE
STALLING. THE UPPER ENERGY DRIVING THIS FRONT WILL WEAKEN AND BECOME
BROAD OVERHEAD...STALLING AS A GREAT LAKES AREA RIDGE BLOSSOMS FROM
THE SOUTHWEST. THIS CREATES A DIFFICULT FORECAST BECAUSE...ALTHOUGH
MOST OF THE AREA WILL BE DRY TUESDAY...THE BROAD LOW OVERHEAD WILL
INTERACT WITH THE SURFACE BOUNDARY TO CAUSE WIDESPREAD RAIN SHOWERS
LURKING JUST OFF THE COAST...POSSIBLY ALONG THE COAST. WINDS THROUGH
THE LOWEST 600MB OF THE COLUMN WILL VEER TO THE E/NE...LIKELY
DRIVING THE BOUNDARY /COASTAL TROUGH/ BACK TOWARDS SHORE. THIS
CREATES INCREASING SHOWER CHANCES ON WEDNESDAY...HIGHEST POP NEAR
THE COAST. ATTM IT LOOKS LIKE THE HEAVIEST RAIN WILL REMAIN JUST
OFFSHORE WITH ONLY LIGHT RAIN ANTICIPATED WITHIN THE CWA.
HOWEVER...THIS WILL NEED TO BE MONITORED CLOSELY AS A VERY SHARP
GRADIENT WILL EXIST BETWEEN HEAVY RAIN AND JUST LIGHT SHOWERS.
TEMPS BOTH TUESDAY AND WEDNESDAY WILL BE BELOW NORMAL FOR LATE
SEPTEMBER...WITH HIGHS IN THE MID/UPR 70S BOTH DAYS.
HOWEVER...TUESDAY WILL HAVE NOTICEABLY MORE SUNSHINE THAN WEDNESDAY.
LOWS TUESDAY NIGHT WILL FEATURE WIDESPREAD 50S...WITH SOME LOW 50S
POSSIBLE WEST OF I-95. MINS WEDNESDAY NIGHT WILL BE SEVERAL DEGREES
WARMER THANKS TO INCREASING ONSHORE FLOW.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 300 AM MONDAY...VERY UNSETTLED THE FIRST HALF OF THE PERIOD AS
THE PATTERN TAKES ON MORE OF A WINTER-LIKE FEEL...BUT IMPROVEMENTS
ARE EXPECTED FOR THE WEEKEND.
DIFFUSE UPPER LOW OVERHEAD THURSDAY WILL WORK IN TANDEM WITH A
COASTAL TROUGH JUST OFFSHORE TO PRODUCE WIDESPREAD CLOUDS AND RAIN
THURSDAY/FRIDAY. STILL UNCERTAINTY EXISTING IN EXACTLY HOW THE
PATTERN WILL EVOLVE LATE-WEEK...AS THERE WILL BE A VERY SHARP
GRADIENT BETWEEN EXTREMELY HIGH PWATS LURKING JUST OFFSHORE...AND
MUCH MORE TYPICAL PWATS TOWARDS I-95. THE DIFFERENCE IS DUE TO THE
COASTAL TROUGH WHICH WILL BE SLOWLY ADVECTING WESTWARD ON DEEP
EASTERLY FLOW...PUSHING THE BETTER RAIN CHANCES TOWARDS THE COAST.
WPC GRAPHICS SHOW THIS GRADIENT WELL...WITH ABOUT 4 INCHES OF QPF
CENTERED JUST OFF THE CAPE FEAR COAST...BUT LESS THAN ONE-QUARTER
INCH IN THE WESTERN ZONES. THE ECMWF IS ONE OF THE MORE PESSIMISTIC
MODELS...BUT IS FAVORED BY WPC...AND THE TREND HAS BEEN FOR A MORE
UNSETTLED THU/FRI PERIOD. WILL BUMP POP TO MDT CHC FOR LATE WEEK AND
CONTINUE WITH HIGHS BELOW CLIMO BUT LOWS SLIGHTLY ABOVE.
THE COASTAL TROUGH WILL BEGIN TO ERODE SATURDAY AS RIDGING FINALLY
DISPLACES THE UPPER TROUGH...BECOMING MORE PRONOUNCED AT THE END OF
THE PERIOD. THIS SUGGESTS DRYING FOR THE WEEKEND...ESPECIALLY AT THE
MID-LEVELS...AND RAIN CHANCES WILL TAKE A DECIDEDLY DOWNWARD TURN
DURING THE WKND...ALTHOUGH IT MAY BE SLOW. IMPROVING CONDITIONS WILL
ALSO ALLOW TEMPS TO RECOVER TO SEASONABLE NORMS.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
AS OF 12Z...A COLD FRONT IS POISED OVER THE NORTHERN PORTION OF THE
CWA. THE IS MOSTLY MID CLOUD ASSOCIATED WITH IT...HOWEVER SOME LIGHT
SHOWERS WILL DEVELOP ALONG THE FRONT THIS MORNING...MAINLY AFFECTING
FLO AND LBT WITH AT WORST INTERMITTENT MVFR CONDITIONS. LATER TODAY
HEAVIER ACTIVITY IS EXPECTED TO DEVELOP OVER THE EXTREME SOUTHEAST
PORTION OF THE CWA...POSSIBLY AFFECTING THE MYRTLES. THERE COULD BE
SOME INTERMITTENT IFR CONDITIONS THERE...WITH POSSIBLE THUNDER. WINDS
POST FRONTAL WILL SHIFT TO THE NORTHEAST...WITH A MID CLOUD CEILING
LINGERING THROUGH THE AFTERNOON HOURS. LIGHT WINDS TONIGHT WITH
LITTLE OR NO FOG EXPECTED.
EXTENDED OUTLOOK...VFR THROUGH WEDNESDAY. RAIN DEVELOPING THURSDAY
AFTERNOON INTO FRIDAY WITH POSSIBLE MVFR/IFR CONDITIONS.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 640 AM MONDAY...THE FRONT IS RUNNING ABOUT TWO HOURS SLOWER
THAN EARLIER MODELS INDICATED. IT HAS CROSSED INTERSTATE 95 AND
SHOULD BE AT THE BEACHES AROUND 9 AM. PREVIOUS DISCUSSION FROM 300
AM FOLLOWS...
A COLD FRONT CURRENTLY EXTENDING ACROSS THE
INTERIOR CAROLINAS WILL MOVE EAST AND OFF THE COAST LATER THIS
MORNING. WESTERLY WINDS WILL TURN NORTH-NORTHEASTERLY BEHIND THE
FRONT...WITH A SUBSTANTIAL INCREASE IN WIND SPEEDS EXPECTED
TONIGHT AS HIGH PRESSURE OVER THE MIDWEST MOVES INTO THE MID-
ATLANTIC STATES. SEAS CURRENTLY RANGING FROM 3-5 FEET WILL
DIMINISH THIS AFTERNOON IN THE LIGHTER WINDS BEHIND THE
FRONT...BUT SHOULD BUILD AGAIN OVERNIGHT IN RESPONSE TO THE
INCREASING NE WIND. WE COULD BE NEAR SMALL CRAFT ADVISORY
THRESHOLDS BY DAYBREAK TUESDAY.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 AM MONDAY...COLD FRONT STALLED JUST OFFSHORE TUESDAY
MORNING WILL REMAIN NEARLY STATIONARY THROUGH MID-WEEK AS HIGH
PRESSURE RIDGES DOWN THE COAST. THIS PRODUCES A PINCHED GRADIENT
OVER THE WATERS...AND PERSISTENT NE WINDS OF 15-25 KTS...WITH LITTLE
FLUCTUATION...BOTH TUESDAY AND WEDNESDAY. THESE GUSTY NE WINDS WILL
DRIVE WAVE HEIGHTS UP TO 4-6 FT FT TUESDAY...AND REMAIN THERE ON
WEDNESDAY...WITH A NE WIND WAVE THE DOMINANT GROUP. A SMALL CRAFT
ADVISORY WILL LIKELY BE NEEDED DURING MUCH OF THE PERIOD...BUT
HOISTING THE HEADLINE WILL WAIT UNTIL MORE CERTAINTY ABOUT THE
TIMING CAN BE DETERMINED. ONCE THE SCA IS ISSUED...IT WILL LIKELY
REMAIN IN EFFECT FOR QUITE SOME TIME.
LONG TERM /THURSDAY THROUGH FRIDAY/...
AS OF 300 AM MONDAY...THE EXTENDED WILL BE MUCH LIKE THE SHORT
TERM...AS A STAGNANT PATTERN KEEPS A COASTAL TROUGH JUST OFFSHORE
AND A HIGH PRESSURE WEDGE INLAND. THIS PRODUCES A PROLONGED PERIOD
OF NE WINDS DUE TO A PINCHED GRADIENT...AND WINDS OF 15-25 KTS WILL
BE COMMON LATE WEEK. THIS EXTENDED PERIOD OF GUSTY NE WINDS WILL
KEEP WAVE HEIGHTS AT 4-6 FT PRETTY MUCH THE ENTIRE FORECAST
PERIOD...AND A SMALL CRAFT ADVISORY WHICH WILL LIKELY BE HOISTED
EARLIER IN THE WEEK...WILL BE NEEDED FOR MOST...IF NOT ALL...OF THE
LONG TERM.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JDW
NEAR TERM...TRA
SHORT TERM...JDW
LONG TERM...JDW
AVIATION...43
MARINE...TRA/JDW
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
645 AM EDT MON SEP 22 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE AREA THIS MORNING BEFORE STALLING
OFFSHORE. AN UPPER LEVEL LOW WILL BRING A CHANCE FOR SOME SHOWERS
AND ISOLATED THUNDERSTORMS THIS AFTERNOON AND TONIGHT. COOLER AND
DRIER WEATHER IS EXPECTED ON TUESDAY. THE STALLED COLD FRONT
OFFSHORE WILL WAVER BACK TOWARDS THE COAST DURING THE MIDDLE AND
LATTER PART OF THE UPCOMING WEEK...BRINGING GOOD CHANCES FOR RAIN
AND BELOW NORMAL TEMPERATURES. A WARMING AND DRYING TREND IS
EXPECTED DURING THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 640 AM MONDAY...UPDATES THIS MORNING FOCUS ON THE CLUSTER OF
SHOWERS FALLING OUT OF A MID-LEVEL CLOUD DECK ACROSS THE PEE DEE
REGION OF SOUTH CAROLINA. 07Z HRRR BRINGS IT STEADILY EASTWARD OVER
THE NEXT FEW HOURS WITH VERY LIGHT RAINFALL AMOUNTS EXPECTED. A NEW
CLUSTER OF CONVECTION IS INDICATED TO DEVELOP IN THE SANTEE
RIVER/CHARLESTON VICINITY BETWEEN 3-5 PM THIS AFTERNOON AHEAD OF THE
UPPER LEVEL DISTURBANCE. THIS WILL PROBABLY BE UPRIGHT CONVECTION
DEVELOPING ALONG AND JUST NORTH OF THE SURFACE FRONT...WITH UPPER
LEVEL WINDS POTENTIALLY BLOWING LIGHT RAIN ANOTHER 30-50 MILES NORTH
OF THE STORMS. NO SIGNIFICANT CHANGES HAVE BEEN MADE TO TEMPS OR
WINDS. PREVIOUS DISCUSSION FROM 300 AM FOLLOWS...
A POTENTIALLY INTERESTING FORECAST IS IN STORE FOR THE EASTERN
CAROLINAS OVER THE NEXT 24 HOURS. A COLD FRONT CURRENTLY EXTENDING
ALONG THE EASTERN EDGE OF THE NC PIEDMONT INTO CENTRAL SOUTH
CAROLINA SHOULD PUSH OFF THE COAST BY MID MORNING WITH
NORTH-NORTHEAST SURFACE WINDS ALLOWING A DRY CANADIAN AIRMASS TO
BUILD SOUTHWARD. THIS IS A SHALLOW AIRMASS CHANGE...WITH WIND
DIRECTIONS REMAINING WEST OR WEST-SOUTHWESTERLY AT AND ABOVE THE 850
MB LEVEL. THE FRONT WILL PUSH OUT JUST BEYOND THE GULF STREAM
TONIGHT WITH STRENGTHENING LOW-LEVEL NORTHEAST FLOW DEVELOPING AS
SURFACE PRESSURES RISE ACROSS THE MID-ATLANTIC REGION WITH HIGH
PRESSURE BUILDING EASTWARD FROM THE MIDWEST. UP AT 500 MB AN UPPER
DISTURBANCE DESCENDING INTO THE SOUTHERN APPALACHIANS THIS AFTERNOON
IS EXPECTED TO CUT OFF TONIGHT OVER WESTERN SOUTH CAROLINA.
THERE ARE A COUPLE CONCERNS WITH THE FORECAST WITHOUT A CLEAR ANSWER
AT THIS EARLY HOUR. THE FIRST IS HOW MUCH MID-LEVEL CLOUD COVER
HANGS AROUND TODAY AND WHAT IMPACT DOES IT HAVE ON TEMPERATURES?
SATELLITE IMAGERY REVEALS A NARROW BAND OF THICK CLOUDS OVER CENTRAL
AL/GA...MATCHING UP QUITE WELL WITH ANALYZED 700 MB RH MODEL FIELDS.
BOTH THE 00Z NAM AND GFS ADVECT THIS MOISTURE ACROSS EASTERN SOUTH
CAROLINA TODAY...LEADING ME TO BELIEVE THERE WILL BE TOO MUCH CLOUD
COVER TO LET TEMPERATURES RISE ABOVE THE LOWER 80S. IN FACT MORE
SUNSHINE UP IN THE LUMBERTON/ELIZABETHTOWN AREA WILL PROBABLY
BALANCE OUT THE OVERALL COOLER AIRMASS TO PRODUCE LOWER 80S ACROSS
THE ENTIRE FORECAST AREA TODAY.
THE SECOND CONCERN IS WITH THE UPPER LOW CUTTING OFF TO OUR WEST
TONIGHT HOW MUCH OVERRUNNING RAIN DEVELOPS? ISENTROPIC LIFT IS
ANTICIPATED TO REMAIN WELL ABOVE THE FRONTAL INVERSION...PROBABLY
NOT BEGINNING IN EARNEST UNTIL THE 310K THETA SURFACE WHICH WILL BE
UP NEAR 600 MB. THE 00Z GFS IS THE MOST AGGRESSIVE WITH BRINGING
RAIN ACROSS EASTERN SC LATE THIS AFTERNOON INTO TONIGHT. GIVEN THE
RELATIVELY WEAK WIND FIELDS PROGGED TO EXIST BELOW 600 MB IT IS HARD
TO BELIEVE THERE WILL BE SIGNIFICANT ADVECTION OF CONVECTIVE SHOWERS
ONSHORE EITHER. MY HIGHEST POP FORECASTS ARE LIMITED TO COASTAL
SOUTH CAROLINA IN THE 40-50 PERCENT RANGE...WITH 15-30 PERCENT
CHANCES ELSEWHERE.
CLOUDS WILL INHIBIT RADIATIONAL COOLING TONIGHT...HOWEVER INCREASING
NORTHEAST WINDS WILL ADVECT IN SIGNIFICANTLY COOLER AIR LEADING TO
LOWS FALLING INTO THE UPPER 50S FROM ELIZABETHTOWN THROUGH DILLON
AND DARLINGTON. LOWER 60S ARE EXPECTED ALONG THE COAST...EXCEPT FOR
SOME MID 60S ALONG THE COAST NEAR SOUTHPORT AND GEORGETOWN.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 AM MONDAY...THE FIRST FULL OF DAY OF FALL ON TUESDAY
BEGINS WITH COLD FRONT POSITIONED JUST OFFSHORE...AS LARGE CANADIAN
HIGH PRESSURE CENTERED OVER THE OH VLY RIDGES DOWN INTO THE
CAROLINAS. ALTHOUGH THIS FRONT WILL BE OFFSHORE...THERE IS SOME
UNCERTAINTY INTO JUST HOW FAR FROM THE COAST IT WILL GET BEFORE
STALLING. THE UPPER ENERGY DRIVING THIS FRONT WILL WEAKEN AND BECOME
BROAD OVERHEAD...STALLING AS A GREAT LAKES AREA RIDGE BLOSSOMS FROM
THE SOUTHWEST. THIS CREATES A DIFFICULT FORECAST BECAUSE...ALTHOUGH
MOST OF THE AREA WILL BE DRY TUESDAY...THE BROAD LOW OVERHEAD WILL
INTERACT WITH THE SURFACE BOUNDARY TO CAUSE WIDESPREAD RAIN SHOWERS
LURKING JUST OFF THE COAST...POSSIBLY ALONG THE COAST. WINDS THROUGH
THE LOWEST 600MB OF THE COLUMN WILL VEER TO THE E/NE...LIKELY
DRIVING THE BOUNDARY /COASTAL TROUGH/ BACK TOWARDS SHORE. THIS
CREATES INCREASING SHOWER CHANCES ON WEDNESDAY...HIGHEST POP NEAR
THE COAST. ATTM IT LOOKS LIKE THE HEAVIEST RAIN WILL REMAIN JUST
OFFSHORE WITH ONLY LIGHT RAIN ANTICIPATED WITHIN THE CWA.
HOWEVER...THIS WILL NEED TO BE MONITORED CLOSELY AS A VERY SHARP
GRADIENT WILL EXIST BETWEEN HEAVY RAIN AND JUST LIGHT SHOWERS.
TEMPS BOTH TUESDAY AND WEDNESDAY WILL BE BELOW NORMAL FOR LATE
SEPTEMBER...WITH HIGHS IN THE MID/UPR 70S BOTH DAYS.
HOWEVER...TUESDAY WILL HAVE NOTICEABLY MORE SUNSHINE THAN WEDNESDAY.
LOWS TUESDAY NIGHT WILL FEATURE WIDESPREAD 50S...WITH SOME LOW 50S
POSSIBLE WEST OF I-95. MINS WEDNESDAY NIGHT WILL BE SEVERAL DEGREES
WARMER THANKS TO INCREASING ONSHORE FLOW.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 300 AM MONDAY...VERY UNSETTLED THE FIRST HALF OF THE PERIOD AS
THE PATTERN TAKES ON MORE OF A WINTER-LIKE FEEL...BUT IMPROVEMENTS
ARE EXPECTED FOR THE WEEKEND.
DIFFUSE UPPER LOW OVERHEAD THURSDAY WILL WORK IN TANDEM WITH A
COASTAL TROUGH JUST OFFSHORE TO PRODUCE WIDESPREAD CLOUDS AND RAIN
THURSDAY/FRIDAY. STILL UNCERTAINTY EXISTING IN EXACTLY HOW THE
PATTERN WILL EVOLVE LATE-WEEK...AS THERE WILL BE A VERY SHARP
GRADIENT BETWEEN EXTREMELY HIGH PWATS LURKING JUST OFFSHORE...AND
MUCH MORE TYPICAL PWATS TOWARDS I-95. THE DIFFERENCE IS DUE TO THE
COASTAL TROUGH WHICH WILL BE SLOWLY ADVECTING WESTWARD ON DEEP
EASTERLY FLOW...PUSHING THE BETTER RAIN CHANCES TOWARDS THE COAST.
WPC GRAPHICS SHOW THIS GRADIENT WELL...WITH ABOUT 4 INCHES OF QPF
CENTERED JUST OFF THE CAPE FEAR COAST...BUT LESS THAN ONE-QUARTER
INCH IN THE WESTERN ZONES. THE ECMWF IS ONE OF THE MORE PESSIMISTIC
MODELS...BUT IS FAVORED BY WPC...AND THE TREND HAS BEEN FOR A MORE
UNSETTLED THU/FRI PERIOD. WILL BUMP POP TO MDT CHC FOR LATE WEEK AND
CONTINUE WITH HIGHS BELOW CLIMO BUT LOWS SLIGHTLY ABOVE.
THE COASTAL TROUGH WILL BEGIN TO ERODE SATURDAY AS RIDGING FINALLY
DISPLACES THE UPPER TROUGH...BECOMING MORE PRONOUNCED AT THE END OF
THE PERIOD. THIS SUGGESTS DRYING FOR THE WEEKEND...ESPECIALLY AT THE
MID-LEVELS...AND RAIN CHANCES WILL TAKE A DECIDEDLY DOWNWARD TURN
DURING THE WKND...ALTHOUGH IT MAY BE SLOW. IMPROVING CONDITIONS WILL
ALSO ALLOW TEMPS TO RECOVER TO SEASONABLE NORMS.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
AS OF 06Z...HIGH CONFIDENCE OF VFR EARLY THIS MORNING AS WINDS
REMAIN ELEVATED AS A COLD FRONT MOVES THROUGH. WINDS WILL SHIFT TO
THE NW 06-07Z AT KFLO/KLBT AND 09-10Z AT THE COASTAL TERMINALS. CIGS
SHOULD REMAIN AT OR ABOVE 4K. ISOLATED LIGHT SHOWERS POSSIBLE WITH
FROPA THUS WILL CONTINUE TO MENTION VCSH. SHOWERS SHOULD DISSIPATE
AFTER SUNRISE AS VFR CONTINUES.
THICKNESS PATTERNS SUGGEST ACTUAL COLD AIR WILL LAG QUITE AWAYS
BEHIND THE FRONT. A SLUGGISH PRESSURE PATTERN MAY CAUSE WIND
DIRECTIONS TO BECOME VARIABLE AT THE COASTAL TERMINALS BY LATE
MORNING OR IN THE AFTERNOON. WEAK LOW LEVEL CONVERGENCE AT THE
COASTAL TERMINALS ALONG WITH INCREASING PVA MAY CAUSE MORE
SIGNIFICANT SHOWER DEVELOPMENT IN THE AFTERNOON. STILL APPEARS VFR
WILL CONTINUE AT THE COASTAL TERMINALS IN THE AFTERNOON. DURING THE
EVENING WINDS WILL BECOME N-NE TERMINAL-WIDE AS HIGH PRESSURE
BUILDS IN.
EXTENDED OUTLOOK...VFR THROUGH WEDNESDAY. RAIN DEVELOPING THURSDAY
AFTERNOON INTO FRIDAY WITH POSSIBLE MVFR/IFR CONDITIONS.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 640 AM MONDAY...THE FRONT IS RUNNING ABOUT TWO HOURS SLOWER
THAN EARLIER MODELS INDICATED. IT HAS CROSSED INTERSTATE 95 AND
SHOULD BE AT THE BEACHES AROUND 9 AM. PREVIOUS DISCUSSION FROM 300
AM FOLLOWS...
A COLD FRONT CURRENTLY EXTENDING ACROSS THE
INTERIOR CAROLINAS WILL MOVE EAST AND OFF THE COAST LATER THIS
MORNING. WESTERLY WINDS WILL TURN NORTH-NORTHEASTERLY BEHIND THE
FRONT...WITH A SUBSTANTIAL INCREASE IN WIND SPEEDS EXPECTED
TONIGHT AS HIGH PRESSURE OVER THE MIDWEST MOVES INTO THE MID-
ATLANTIC STATES. SEAS CURRENTLY RANGING FROM 3-5 FEET WILL
DIMINISH THIS AFTERNOON IN THE LIGHTER WINDS BEHIND THE
FRONT...BUT SHOULD BUILD AGAIN OVERNIGHT IN RESPONSE TO THE
INCREASING NE WIND. WE COULD BE NEAR SMALL CRAFT ADVISORY
THRESHOLDS BY DAYBREAK TUESDAY.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 AM MONDAY...COLD FRONT STALLED JUST OFFSHORE TUESDAY
MORNING WILL REMAIN NEARLY STATIONARY THROUGH MID-WEEK AS HIGH
PRESSURE RIDGES DOWN THE COAST. THIS PRODUCES A PINCHED GRADIENT
OVER THE WATERS...AND PERSISTENT NE WINDS OF 15-25 KTS...WITH LITTLE
FLUCTUATION...BOTH TUESDAY AND WEDNESDAY. THESE GUSTY NE WINDS WILL
DRIVE WAVE HEIGHTS UP TO 4-6 FT FT TUESDAY...AND REMAIN THERE ON
WEDNESDAY...WITH A NE WIND WAVE THE DOMINANT GROUP. A SMALL CRAFT
ADVISORY WILL LIKELY BE NEEDED DURING MUCH OF THE PERIOD...BUT
HOISTING THE HEADLINE WILL WAIT UNTIL MORE CERTAINTY ABOUT THE
TIMING CAN BE DETERMINED. ONCE THE SCA IS ISSUED...IT WILL LIKELY
REMAIN IN EFFECT FOR QUITE SOME TIME.
LONG TERM /THURSDAY THROUGH FRIDAY/...
AS OF 300 AM MONDAY...THE EXTENDED WILL BE MUCH LIKE THE SHORT
TERM...AS A STAGNANT PATTERN KEEPS A COASTAL TROUGH JUST OFFSHORE
AND A HIGH PRESSURE WEDGE INLAND. THIS PRODUCES A PROLONGED PERIOD
OF NE WINDS DUE TO A PINCHED GRADIENT...AND WINDS OF 15-25 KTS WILL
BE COMMON LATE WEEK. THIS EXTENDED PERIOD OF GUSTY NE WINDS WILL
KEEP WAVE HEIGHTS AT 4-6 FT PRETTY MUCH THE ENTIRE FORECAST
PERIOD...AND A SMALL CRAFT ADVISORY WHICH WILL LIKELY BE HOISTED
EARLIER IN THE WEEK...WILL BE NEEDED FOR MOST...IF NOT ALL...OF THE
LONG TERM.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JDW
NEAR TERM...TRA
SHORT TERM...JDW
LONG TERM...JDW
AVIATION...TRA
MARINE...TRA/JDW
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
649 AM EDT MON SEP 22 2014
.SYNOPSIS...
A LARGE AREA OF HIGH PRESSURE OVER THE NORTHERN AND CENTRAL PLAINS
WILL SETTLE OVER THE OHIO VALLEY TONIGHT AND TUESDAY. HIGH
PRESSURE IS THEN FORECAST TO EXTEND ACROSS THE REGION THROUGH THE
END OF THE WEEK. TEMPERATURES WILL START OUT COOL EARLY THIS
WEEK...FOLLOWED BY A WARMING TREND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LARGE SCALE MID LEVEL TROUGH OVER THE EASTERN GREAT LAKES THIS
MORNING WILL SHIFT EAST INTO NEW ENGLAND AND EASTERN CANADA
THROUGH TODAY. AS THIS OCCURS...A SPRAWLING AREA OF SURFACE HIGH
PRESSURE OVER THE NORTHERN AND CENTRAL PLAINS WILL MOVE/BUILD
SOUTHEAST INTO OUR REGION. MAIN FORECAST DILEMMA TODAY WILL BE
FIGURING OUT THE COVERAGE OF CAA STRATOCUMULUS AND HOW FAST THEY
WILL EXIT THE AREA. HAVE USED THE RAP MODEL AS A GUIDE TO FIGURE
THIS OUT WHICH KEEPS ROUGHLY THE EASTERN TWO THIRDS MOSTLY CLOUDY
THROUGH MID MORNING FOLLOWED BY CLEARING SKIES AS SUBSIDENCE...DRYING
AND ANTICYCLONIC FLOW INCREASE FROM THE WEST. TEMPERATURES WILL BE
BELOW NORMAL FOR THE ARRIVAL OF AUTUMN WITH HIGHS RANGING FROM THE
LOWER TO MID 60S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
SURFACE HIGH PRESSURE WILL SETTLE OVER THE OHIO VALLEY TONIGHT.
CLEAR SKIES...LIGHT TO CALM WINDS...AND A DRY AIRMASS WILL MAKE
FOR FAVORABLE RADIATIONAL COOLING CONDITIONS. HAVE USED A BLEND OF
THE ADJUSTED MAV GUIDANCE AND CONSENSUS RAW 2 METER TEMPERATURES
TO TRY TO CAPTURE THE NORMALLY COOL SPOTS. LOWS WILL RANGE FROM
THE UPPER 30S IN THOSE COOL SPOTS TO THE MID 40S AT RIDGE TOPS AND
NEAR URBAN AREAS.
THE HIGH WILL REMAIN IN PLACE ON TUESDAY. SUNNY SKIES AND A
MODIFYING AIRMASS WILL ALLOW TEMPERATURES TO WARM INTO THE UPPER
60S TO THE LOWER 70S.
A MID LEVEL RIDGE WILL BUILD INTO THE GREAT LAKES AND MIDDLE OHIO
VALLEY TUESDAY NIGHT INTO WEDNESDAY. AT THE SAME TIME...SURFACE
HIGH PRESSURE WILL EXTEND FROM NEW ENGLAND INTO THE OHIO VALLEY.
LITTLE IF ANY CLOUD COVER IS EXPECTED THROUGH THE PERIOD. A
WARMING TREND WILL CONTINUE DUE TO A WARMING/MODIFYING AIRMASS.
DIURNAL SWINGS OF 25 TO 30 DEGREES WILL BE LIKELY GIVEN THE DRY
AIRMASS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
MID/UPPER LEVEL RIDGING WILL REMAIN IN CONTROL THROUGH THE LONG TERM
PERIOD. THE MODELS ARE HINTING AT SOME MOISTURE POSSIBLY TRYING TO
WORK UP FROM THE SOUTH HEADING INTO THE WEEKEND...BUT WITH RIDGING
OVERHEAD...WILL MAINTAIN A DRY FORECAST. TEMPERATURES WILL
CONTINUE TO SLOWLY WARM AS THE AIRMASS CONTINUES TO MODIFY/WARM THROUGH
THE END OF THE WEEK. TEMPERATURES THROUGH THIS PERIOD SHOULD RUN
A FEW DEGREES ABOVE NORMAL.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
PATCHY MVFR CLOUDS ARE PERSISTING ACROSS THE REGION THIS
MORNING. OVERALL CLOUD BASES GENREALLY RANGE FROM AROUND 2000-3000
FEET...WITH A FEW AREAS OF CEILINGS AS LOW AS 1500 FEET. THESE
CLOUDS ARE EXPECTED TO REMAIN IN PLACE FOR THE NEXT FEW
HOURS...ESPECIALLY AFFECTING THE CENTRAL OHIO TAF SITES. CEILINGS
SHOULD LIFR TO VFR BY LATE MORNING.
NNW WINDS WILL GENERALLY REMAIN IN THE 6-12 KNOT RANGE
TODAY...BEFORE DIMINISHING THIS EVENING. WITH HIGH PRESSURE
MOVING INTO THE AREA...CLEAR SKIES AND LIGHT WINDS WILL PERSIST
INTO THE OVERNIGHT HOURS AND THROUGH TUESDAY.
OUTLOOK...NO SIGNIFICANT WEATHER IS EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HICKMAN
NEAR TERM...HICKMAN
SHORT TERM...HICKMAN
LONG TERM...JGL
AVIATION...HATZOS
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
532 AM MDT MON SEP 22 2014
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 322 AM MDT MON SEP 22 2014
A FEW SHOWERS MOVING NORTHEAST ACROSS NORTHERN COLORADO BUT HAVING
SOME TROUBLE SURVIVING OFF THE MOUNTAINS SO FAR. MEANWHILE AN
UPPER LOW CURRENTLY AROUND THE UTAH/IDAHO BORDER WILL MOVE
NORTHWARD THIS MORNING THEN TURN MORE EASTWARD THROUGH THIS
EVENING EMERGING OVER THE NORTHERN HIGH PLAINS TONIGHT. AN IMPULSE
ROTATING AROUND THE UPPER LOW WILL SWING ACROSS THE CWA THIS
AFTERNOON AND EVENING WITH SCTD SHOWERS AND TSTRMS ASSOCIATED WITH
IT. INSTABILITY WILL BE RATHER WEAK ACROSS MUCH OF THE CWA THIS
AFTERNOON BUT A TONGUE OF BETTER INSTABILITY/CAPES 500-100 J/KG/
LOOKS TO NOSE UP OUT OF COLORADO INTO MAINLY THE SOUTHERN
PANHANDLE INTO THIS EVENING WHICH WITH MARGINAL SHEAR MAY ALLOW
FOR A FEW STRONGER STORMS THERE. ACTIVITY WILL MOVE OUT OF THE CWA
TONIGHT AS THE UPPER IMPULSE SWINGS EAST OF THE AREA AND A WEAK
PACIFIC FRONT MOVES OUT ACROSS THE HIGH PLAINS. MAINLY DRY AND
WARM TUESDAY THOUGH ANOTHER MODEST SHORTWAVE CLIPPING NORTHEAST
PARTS OF THE CWA MAY SET OFF A FEW SHOWERS/TSTMS OVER THAT AREA
TUESDAY AFTERNOON. DRY AND WARMER WEDS AS AN UPPER RIDGE AMPLIFIES
AND BUILDS NORTHEAST ACROSS THE NORTHERN AND CENTRAL ROCKIES.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 322 AM MDT MON SEP 22 2014
SHARP UPPER LEVEL RIDGING BUILDS INTO THE AREA WEDNESDAY NIGHT
INTO THURSDAY. 700MB TEMPERATURES RESPOND AS WELL...CLIMBING TO
+14C AND EVEN +16C ACROSS PORTIONS OF SOUTHERN CARBON AND ALBANY
COUNTIES THURSDAY AFTERNOON. THIS IS UP FROM +10C TO +12C
WEDNESDAY AFTERNOON. AS A RESULT...TEMPERATURES SHOULD BE WARMER
AND ALMOST SUMMER LIKE WITH 90S IN THE PANHANDLE AND MID 80S OUT
WEST. GOING TO BE DRY THROUGH AT LEAST FRIDAY AS WELL WITH SUNNY
SKIES AND LIGHT WINDS.
WEATHER BEGINS TO CHANGE SOME FRIDAY NIGHT INTO SATURDAY. MODELS
INITIALLY IN GOOD AGREEMENT WITH A PACIFIC LOW PRESSURE SYSTEM
MOVING INTO NEVADA OVERNIGHT FRIDAY. GFS MUCH FASTER...BY ROUGHLY
12 TO 18 HOURS ON THE EASTWARD MOVEMENT OF THIS LOW. NEW ECMWF
SLOWER AND HAS THE LOW NOT MOVING INTO NEVADA UNTIL SATURDAY
NIGHT/SUNDAY MORNING. GFS SOLUTION WOULD HAVE FAIRLY WIDESPREAD
SHOWER ACTIVITY FOR AREAS ALONG AND WEST OF THE LARAMIE RANGE
SATURDAY NIGHT INTO SUNDAY. ECMWF SOLUTION HAS SHOWERS MOVING INTO
CARBON COUNTY SUNDAY NIGHT INTO MONDAY. DID A BLEND OF THE TWO
MODELS FOR POPS OVER THE WEEKEND WITH LOW CHANCE POPS SATURDAY
NIGHT. BEST CHANCES LOOK TO BE THROUGH THE DAY SUNDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 529 AM MDT MON SEP 22 2014
LATEST MOSAIC RADAR SHOWING AREA OF SHOWERS OVER NORTH CENTRAL
COLORADO CONTINUING TO MOVE NORTHEAST. SHOULD BE INTO THE SOUTH
LARAMIE RANGE HERE BY SUNRISE. FORTUNATELY...LATEST HRRR SHOWING
VFR CONDITIONS WITH SOUTHWEST WINDS IN THIS AREA OF SHOWERS. SO
FLIGHT OPERATIONS SHOULD NOT BE OVERLY IMPACTED.
&&
.FIRE WEATHER...
ISSUED AT 322 AM MDT MON SEP 22 2014
NO SIGNIFICANT CONCERNS EXPECTED THROUGH AT LEAST MIDWEEK WITH MIN
RELATIVE HUMIDITIES EXPECTED TO REMAIN ABOVE CRITICAL LEVELS FOR
THE MOST PART. GUSTY WINDS EXPECTED THIS AFTERNOON OVER WESTERN
AREAS THEN LESS WIND ANTICIPATED TUESDAY AND WEDS. SCTD SHOWERS
AND TSTRMS TODAY WITH ACTIVITY MOVING EAST AND OUT OF THE AREA
THIS EVENING.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...RE
LONG TERM...CLAYCOMB
AVIATION...CLAYCOMB
FIRE WEATHER...RE
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
658 PM EDT MON SEP 22 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE AREA TONIGHT. TUESDAY THROUGH
EARLY NEXT WEEK...STRONG HIGH PRESSURE WILL EXTEND INTO THE REGION
FROM THE NORTH...AND A TROUGH OF LOW PRESSURE WILL PERSIST NEAR
THE COAST.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
MAJOR CHANGES HAVE BEEN MADE IN THE SHORT TERM AS TEMPERATURES
HAVE COOLED SIGNIFICANTLY IN THE WAKE OF SHOWERS/TSTMS. IT APPEARS
THE FRONT HAS BEEN PUSHED OFFSHORE DUE TO CONVECTIVE OUTFLOW AND A
BUBBLE HIGH THAT HAS DEVELOPED OVER THE SOUTHERN MIDLANDS. HIGHEST
RAIN CHANCES WILL BE CLUSTERED ALONG THE COAST OVERNIGHT AS
ISENTROPIC ASSENT ATOP THE OFFSHORE FRONT INCREASES IN RESPONSE TO
THE UPPER LOW CUTTING OFF OVER THE CENTRAL GEORGIA. NEAR TERM POPS
HAVE BEEN INCREASED TO 100 PERCENT ALONG THE COAST WITH 60-70
PERCENT INLAND. A RISK FOR FLASH FLOODING CONTINUES FOR PORTIONS
OF THE CHARLESTON TRI-COUNTY AREA...ESPECIALLY IN BERKELEY COUNTY.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
IN THE WAKE OF COLD FROPA...THE OVERALL PATTERN WILL FEATURE STRONG
HIGH PRESSURE CENTERED NORTH OF THE REGION...A PERSISTENT TROUGH OF
LOW PRESSURE OVER COASTAL WATERS/CLOSE TO THE COAST AND A CUT-OFF
UPPER LOW MEANDERING OVER OR CLOSE TO THE REGION. THE SYNOPTIC
PATTERN WILL FAVOR PLENTY OF CLOUDS...BELOW NORMAL HIGH TEMPERATURES
MAINLY IN THE 70S AND SOME DEGREE OF POPS MUCH OF THE TIME...TAPERED
FROM SLIGHT CHANCE/CHANCE INLAND TO CHANCE/LIKELY NEAR THE COAST.
CHANGES SHOULD REMAIN SUBTLE...AND FORECAST DETAILS INCLUDING
DEVIATIONS FROM THIS GENERAL SCENARIO WILL BE ADDRESSED WITHIN
SUBSEQUENT FORECAST PACKAGES...ESPECIALLY WITHIN THE UPCOMING NEAR
TERM PERIODS.
HIGHEST PWATS AND DEEPEST MOISTURE SHOULD REMAIN JUST OFF THE COAST.
HOWEVER...SOME POTENTIAL EXISTS FOR DEEP MOISTURE/AN ASSOCIATED
HEAVY RAIN THREAT TO PERIODICALLY BACK INTO COASTAL
COUNTIES...DEPENDING IN PART ON THE ORIENTATION/EVOLUTION OF THE
UPPER LOW.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
PERHAPS ONE OF THE LONGEST HIGH PRESSURE WEDGE PATTERNS IS IN STORE
FOR THE MEDIUM TO LONG RANGE PERIODS. THE EXPANSIVE SURFACE HIGH
OVER THE NORTHEAST STATES LOOKS TO REMAIN IN PLACE THROUGH SATURDAY
NIGHT WHILE A COASTAL TROUGH MAINTAINS CONSIDERABLE CLOUDINESS...
BETTER RAIN CHANCES AND COOL TEMPS. SUNDAY INTO MONDAY THERE ARE
LARGE MODEL DIFFERENCES REGARDING THE POTENTIAL FOR A DEEP LONGWAVE
UPPER TROUGH MOVING INTO THE EASTERN UNITED STATES. A GULF LOW
PRESSURE SYSTEM MAY LIFT NORTHEAST LATE IN THE WEEKEND OR EARLY NEXT
WEEK.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
KCHS...-RA WILL PERSIST AT KCHS WITH A RISK FOR SHOWER IMMEDIATE
SHOWER IMPACTS LASTING TO ABOUT 03Z. SHOWER ACTIVITY WILL BECOME
MORE SCATTERED IN NATURE OVERNIGHT SO ITS HARD TO PIN DOWN EXACTLY
WHEN SHOWERS WILL AFFECT THE TERMINAL AFTER 03Z. WILL NOT CARRY
ANY MENTION OF SHOWERS OVERNIGHT INTO TUESDAY...ALTHOUGH THERE
WILL BE A RISK. LARGE DISCREPANCIES ON HOW LOW CIGS WILL GET
OVERNIGHT. THE LATEST NAM AND LAV GUIDANCE KEEPS CIGS VFR WHILE
THE RUC CRASHES CIGS TO LIFR AFTER 06Z. VERY TOUGH CALL ON THIS.
OPTED TO A MIDDLE OF THE ROAD APPROACH WITH PREVAILING LOW-END
MVFR CIGS 05-14Z WITH VFR THEREAFTER. AMENDMENTS WILL MOST
CERTAINLY BE NEEDED OVERNIGHT AS TRENDS BECOME MORE APPARENT.
KSAV...SHOWER ACTIVITY HAS GENERALLY ENDED...THOUGH LOW-END
SCATTERED ACTIVITY WILL LINGER WEST AND NORTH OF THE TERMINAL
THROUGH 05Z. OPTED FOR A TEMPO GROUP FOR HIGH END MVFR VSBYS IN
-SHRA 02-05Z TO COVER. PREVAILING MVFR CIGS THEREAFTER WITH VFR
RETURNING BY 14Z.
EXTENDED AVIATION OUTLOOK...THU FRI BRIEF FLIGHT RESTRICTIONS
POSSIBLE IN SCATTERED SHOWERS TUESDAY THROUGH FRIDAY. CHANCES FOR
MVFR CEILINGS INCREASE THURSDAY INTO FRIDAY AS LOW PRESSURE
STRENGTHENS OFF THE COAST.
&&
.MARINE...
TONIGHT...THE APPROACHING COLD FRONT WILL BEGIN TO MOVE INTO AND
THROUGH THE WATERS THIS EVENING. LIGHT SOUTHWEST FLOW WILL TURN
AROUND TO EVENTUALLY BECOME NORTHEASTERLY THANKS TO THE HIGH
PRESSURE BUILDING IN TO THE NORTH. THE STRENGTHENING NORTHEAST
GRADIENT WILL SUPPORT A NOTEWORTHY SURGE LATE TONIGHT WITH ALMOST
ALL OF THE WATERS BECOMING 15-20 KT. FOR NOW IT APPEARS THAT SMALL
CRAFT ADVISORY WINDS WILL BE DELAYED UNTIL TUESDAY WHEN THE GRADIENT
TIGHTENS MORE. ALSO...SINCE THE STRONGEST WINDS WILL NOT ARRIVE
UNTIL AFTER THE TONIGHT PERIOD...SEAS WILL GENERALLY REMAIN 2-3 FT
TONIGHT WITH A FEW 4 FOOTERS PERHAPS BLEEDING INTO THE CHARLESTON
COUNTY WATERS VERY LATE. THUNDERSTORMS ALONG THE FRONT COULD BE
STRONG TO SEVERE THIS EVENING...WITH THE MAIN THREAT BEING WIND
GUSTS OF 40 KT.
HIGH PRESSURE TO THE NORTH...A COASTAL TROUGH AND SOME DEGREE OF
MARINE LAYER INSTABILITY/MIXING WILL CONTRIBUTE TO A PROLONGED
PERIOD OF ELEVATED NORTHEAST WINDS/ASSOCIATED ELEVATED SEAS
TUESDAY THROUGH FRIDAY. TO ADDRESS THE INITIAL SURFACE OF STRONG
NORTHEAST WINDS AND BUILDING SEAS...RAISED SMALL CRAFT ADVISORIES
FOR ALL MARINE ZONES BEGINNING TUESDAY MORNING NORTH...INCLUDING
CHARLESTON HARBOR...AND EARLY TUESDAY AFTERNOON SOUTH. PER GUIDANCE
SIGNALS SUGGESTING A SUBTLE LULL IN WINDS/SEAS THURSDAY...ENDED ALL
ADVISORIES AT 5 AM THURSDAY MORNING. HOWEVER...CONFIDENCE IS NOT
HIGH THAT ANY LULL WILL OCCUR...AND ADJUSTMENTS TO SMALL CRAFT
ADVISORY TIMES COULD BE NEEDED TOWARD MIDWEEK.
RIP CURRENTS...LOCAL GUIDANCE YIELDED A MODERATE RISK FOR RIP
CURRENTS ON AREA BEACHES TUESDAY...MAINLY DUE TO STRONG ONSHORE
WINDS. AN ELEVATED RISK FOR RIP CURRENTS WILL CONTINUE THROUGH AT
LEAST LATE THIS WEEK...AND PERHAPS EVEN INTO THE WEEKEND.
&&
.TIDES/COASTAL FLOODING...
INCREASING NORTHEAST FLOW TUESDAY THROUGH NEXT WEEKEND WILL RESULT
IN MODERATE CHANCES FOR SHALLOW COASTAL/SALT WATER FLOODING AROUND
THE TIMES OF HIGH TIDE ESPECIALLY ALONG THE SC COAST INCLUDING
DOWNTOWN CHARLESTON. SINCE RAINFALL AMOUNTS ARE EXPECTED TO BE
HIGHEST NEAR THE COAST THROUGH THE PERIOD...SOME POTENTIAL EXISTS
FOR A COMBINATION OF FRESH/SALT WATER FLOODING IF HEAVY RAIN FALLS
NEAR THE TIMES OF HIGH TIDE.
&&
.EQUIPMENT...
THE DOWNTOWN CHARLESTON WEATHER SENSOR AT WATERFRONT PARK /KCXM/
IS INOPERABLE. IT IS UNKNOWN AT THIS TIME WHEN THE SENSOR WILL BE
RETURNED TO SERVICE. HOURLY OBSERVATIONS AND DAILY CLIMATE
INFORMATION WILL NOT BE AVAILABLE UNTIL FURTHER NOTICE.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 11 AM TUESDAY TO 5 AM EDT THURSDAY
FOR AMZ330-352.
SMALL CRAFT ADVISORY FROM 8 AM TUESDAY TO 5 AM EDT THURSDAY
FOR AMZ350.
SMALL CRAFT ADVISORY FROM 2 PM TUESDAY TO 5 AM EDT THURSDAY
FOR AMZ354-374.
&&
$$
ST
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
226 PM CDT MON SEP 22 2014
.DISCUSSION...
135 AM CDT
SYNOPSIS...AN EXTENDED PERIOD OF QUIET AND DRY WEATHER IS EXPECTED
THROUGH NEXT WEEKEND. WE WILL ALSO BE EXPERIENCING A SLOW WARMING
TREND WITH HIGHS IN THE 60S TODAY AND THEN HIGHS IN THE MID TO UPPER
70S BY LATE WEEK.
TODAY THROUGH TUESDAY...
THE UPPER LEVEL TROUGH IS PUSHING EAST AND AN UPPER LEVEL RIDGE WILL
MOVE OVER THE REGION TONIGHT AND TUESDAY. HIGH PRESSURE IS OVER THE
CENTRAL PLAINS EARLY THIS MORNING AND IT WILL DRIFT EAST OVER THE
CWA TODAY. THE GRADIENT WILL WEAKEN ALLOWING WINDS TO DIMINISH THIS
MORNING AND BECOME WEST TO SOUTHWEST BY THIS AFTERNOON. A WEAK LAKE
BREEZE IS POSSIBLE IN COOK COUNTY LATE THIS AFTN. LOOKING AT A
BEAUTIFUL SUNNY FALL DAY WITH HIGHS IN THE 60S.
CLEAR CONDITIONS AND LIGHT WINDS CONTINUE TONIGHT WITH LOWS IN THE
50S NEAR THE LAKE AND IN THE 40S IN THE OUTLYING AREAS.
THE CENTER OF THE HIGH MOVES OVER THE UPPER OHIO RIVER VALLEY
TOMORROW AND LOOKING AT ANOTHER DRY AND SUNNY DAY. HIGH TEMPS WILL
BE A BIT WARMER IN THE LOW 70S. THE WEAK PRESSURE GRADIENT MAY
ALLOW A LAKE BREEZE TO FORM LATE IN THE AFTERNOON SO MAY SEE TEMPS
STAY AROUND 70 ALONG THE LAKE. OTHERWISE LIGHT SW WINDS WILL
BECOME S TO SE IN THE AFTERNOON.
JEE
TUESDAY NIGHT THROUGH THURSDAY...
LARGE ANTI-CYCLONIC FEATURE WILL PERSIST...WITH A CONTINUED THEME OF
DRY WEATHER AND LIGHT WINDS. MINIMAL CLOUD COVER DURING THE
OVERNIGHT HOURS WITH LIGHT WINDS WILL ALLOW TEMPS TO EASILY RADIATE
INTO THE UPR 40S/LOW 50S. AFTN HIGHS WILL RETURN TO NEAR SEASONAL
CONDS GENERALLY IN THE LOW/MID 70S. POTENTIAL FOR A LAKE BREEZE IN
THE AFTN HOURS WILL BRING COOLER TEMPS TO AREAS ADJACENT TO LAKE
MICHIGAN.
HIGH CONFIDENCE IN THE MEDIUM TERM.
FRIDAY THROUGH SUNDAY...
ENSEMBLES CONTINUE THE DRY THEME INTO THE UPCOMING WEEKEND...WITH
MID-LVL RIDGING PROGGED TO SLIDE OVERHEAD AND AMPLIFY SLIGHTLY
FRI/SAT. THIS WILL LIKELY RESULT IN A CONTINUED MODERATION TO AFTN
TEMPS...POSSIBLY GOING ABOVE CLIMO IN THE UPR 70S TO PERHAPS 80
DEGREES SOUTH OF I-80 FRI/SAT. FOR THE SECOND HALF OF THE WEEKEND
ENSEMBLE SUGGEST THE MID-LVL RIDGE WILL BEGIN TO DISSOLVE AND DRIFT
EAST...WITH THE LONGWAVE PATTERN TURNING MORE SOUTHWESTERLY AS THE
TROUGH ACROSS THE FOUR-CORNERS REGION BEGINS TO PIVOT EAST INTO THE
SOUTHERN PLAINS. AT THIS TIME THOUGH GUIDANCE SUGGESTS PRECIP WILL
REMAIN WEST OF THE FORECAST AREA THRU THE WEEKEND. GIVEN THE DRY
CONDS AND MINIMAL CLOUDS/LGT WINDS...EXPECT OVERNIGHT LOWS TO EASILY
RADIATE INTO THE LOW/MID 50S.
HIGH CONFIDENCE IN THE EXTENDED FORECAST.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* NONE.
KJB
//DISCUSSION...UPDATED 18Z...
SURFACE HIGH PRESSURE WILL DOMINATE ACROSS THE REGION THROUGH THE
PERIOD. THIS WILL RESULT IN FAIRLY QUIET WEATHER CONDITIONS OVER THE
AREA. AS A RESULT...NO SIGNIFICANT AVIATION WEATHER CONCERNS ARE
EXPECTED. AN AFTERNOON LAKE BREEZE WILL LIKELY DEVELOP
TODAY...HOWEVER...IT APPEARS THAT IT MAY REMAIN EAST OF THE MAIN AIR
FIELDS. EVEN IF IT WERE TO MAKE IT ALL THE WAY TO ORD OR MDW LATE
THIS AFTERNOON...WIND SPEEDS WOULD LIKELY REMAIN BELOW THE 10 KT
THRESHOLDS. OTHERWISE...EXPECT A PREDOMINATELY LIGHT WESTERLY
COMPONENT TO THE WIND TODAY AND TONIGHT...THEN GRADUALLY BACKING MORE
SOUTHEASTERLY BY LATE TUESDAY AFTERNOON AS THE SURFACE HIGH DEPARTS
TO THE EAST.
KJB
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH FOR ALL ELEMENTS.
KJB
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT THROUGH SUNDAY...VFR.
JEE
&&
.MARINE...
224 PM CDT
HIGH PRESSURE IS CENTERED OVER THE MID/UPPER MISSISSIPPI VALLEY THIS
AFTERNOON WITH RIDGING EXTENDING OVER SOUTHERN LAKE MICHIGAN WHICH
HAS RESULTED IN DIMINISHING WINDS TODAY. WAVES HAVE BEEN STEADILY
SUBSIDING TODAY WITH WAVES AT THE MICHIGAN CITY BUOY BELOW 4 FT...
SO WILL CANCEL THE REMAINDER OF THE SMALL CRAFT ADVISORY FOR THE
NEARSHORE WATERS THIS AFTERNOON. THROUGH MIDWEEK...THE HIGH WILL
TRANSLATE EAST ACROSS THE OHIO VALLEY INTO NEW ENGLAND WITH WINDS
GRADUALLY BACKING TO THE SOUTH BY TUESDAY EVENING WHERE THEY
SHOULD GENERALLY STAY THROUGH THE END OF THE WEEK.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 4 PM MONDAY.
SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 10 PM MONDAY.
&&
$$
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
1226 PM CDT Mon Sep 22 2014
.UPDATE...
ISSUED AT 1045 AM CDT MON SEP 22 2014
The forecast generally looks on track today with just very minor
updates to sky grids over eastern IL where few to scattered
cumulus clouds from I-57 east, especially near IN/IL border per
NAM and RUC curule but still mostly sunny skies. Highs in the
upper 60s to around 70F with north winds 5-10 mph.
1028 mb high pressure over nw IL and northern MO late this morning to
settle over central IL tonight and continue fair weather with
temperatures a bit below normal. Temps currently in the upper 50s
and lower 60s should climb about another 10 degrees for highs in
the upper 60s to around 70F this afternoon. Coolest readings over
east central IL.
&&
.SHORT TERM...(Today)
ISSUED AT 341 AM CDT MON SEP 22 2014
High pressure centered over eastern Nebraska will move east into the
area today. This will bring clear skies, dry weather and light
winds. Even with lots of sunshine today, highs are only expected
to reach into the upper 60s to around 70 degrees. GFS MOS guidance
looks several degrees too warm, while the NAM is too cool.
&&
.LONG TERM...(Tonight through Sunday)
ISSUED AT 341 AM CDT MON SEP 22 2014
An extended period of quiet weather throughout the remainder of the
forecast with high pressure building into and remaining in control
of the Midwest. Surface ridge dominating much of the eastern half
of the CONUS and keeping the weather quiet and fair, with slowly
warming temps through the work week. Weak flow under the sfc high
becomes more southerly on Tuesday as the ridge axis shifts slightly
eastward. Warming trend continues with the thermal ridging over
the desert SW slowly advecting into the center of the country and
max temps are just above normals by Thursday. A weak trof brings
some precip to the Plains Wednesday, but the ridge remains in place
and dry air eroding the activity before impacting Central Illinois.
In the extended, the GFS pushes some minor precip into the extreme
SE with an oddly evolving upper pattern beyond day 6. ECMWF
remaining dry and energy aloft without significant flow seeming to
retrograde somewhat under a larger scale ridge. Keeping the
forecast dry for next weekend until the models become a little more
cohesive with their solutions under the pattern shift.
&&
.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
ISSUED AT 1225 PM CDT MON SEP 22 2014
VFR conditions should continue across the central IL terminal
airports through Tuesday. Clear skies to generally prevail with
just a few cumulus clouds around 3k ft possible from CMI east.
1027 mb high pressure near the IL/IA border and northern MO will
drift east across central IL tonight and into the Ohio river
valley on Tue. This will continue the fair/dry weather across
central IL, with no fog expected overnight due to dry airmass.
Winds to stay light out of the north near 5 kts today, then light
and variable to calm at times tonight, and light se winds afer
14Z/9 am Tue.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...07
SHORT TERM...AUTEN
LONG TERM...HJS
AVIATION...07
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1105 AM CDT MON SEP 22 2014
.DISCUSSION...
135 AM CDT
SYNOPSIS...AN EXTENDED PERIOD OF QUIET AND DRY WEATHER IS EXPECTED
THROUGH NEXT WEEKEND. WE WILL ALSO BE EXPERIENCING A SLOW WARMING
TREND WITH HIGHS IN THE 60S TODAY AND THEN HIGHS IN THE MID TO UPPER
70S BY LATE WEEK.
TODAY THROUGH TUESDAY...
THE UPPER LEVEL TROUGH IS PUSHING EAST AND AN UPPER LEVEL RIDGE WILL
MOVE OVER THE REGION TONIGHT AND TUESDAY. HIGH PRESSURE IS OVER THE
CENTRAL PLAINS EARLY THIS MORNING AND IT WILL DRIFT EAST OVER THE
CWA TODAY. THE GRADIENT WILL WEAKEN ALLOWING WINDS TO DIMINISH THIS
MORNING AND BECOME WEST TO SOUTHWEST BY THIS AFTERNOON. A WEAK LAKE
BREEZE IS POSSIBLE IN COOK COUNTY LATE THIS AFTN. LOOKING AT A
BEAUTIFUL SUNNY FALL DAY WITH HIGHS IN THE 60S.
CLEAR CONDITIONS AND LIGHT WINDS CONTINUE TONIGHT WITH LOWS IN THE
50S NEAR THE LAKE AND IN THE 40S IN THE OUTLYING AREAS.
THE CENTER OF THE HIGH MOVES OVER THE UPPER OHIO RIVER VALLEY
TOMORROW AND LOOKING AT ANOTHER DRY AND SUNNY DAY. HIGH TEMPS WILL
BE A BIT WARMER IN THE LOW 70S. THE WEAK PRESSURE GRADIENT MAY
ALLOW A LAKE BREEZE TO FORM LATE IN THE AFTERNOON SO MAY SEE TEMPS
STAY AROUND 70 ALONG THE LAKE. OTHERWISE LIGHT SW WINDS WILL
BECOME S TO SE IN THE AFTERNOON.
JEE
TUESDAY NIGHT THROUGH THURSDAY...
LARGE ANTI-CYCLONIC FEATURE WILL PERSIST...WITH A CONTINUED THEME OF
DRY WEATHER AND LIGHT WINDS. MINIMAL CLOUD COVER DURING THE
OVERNIGHT HOURS WITH LIGHT WINDS WILL ALLOW TEMPS TO EASILY RADIATE
INTO THE UPR 40S/LOW 50S. AFTN HIGHS WILL RETURN TO NEAR SEASONAL
CONDS GENERALLY IN THE LOW/MID 70S. POTENTIAL FOR A LAKE BREEZE IN
THE AFTN HOURS WILL BRING COOLER TEMPS TO AREAS ADJACENT TO LAKE
MICHIGAN.
HIGH CONFIDENCE IN THE MEDIUM TERM.
FRIDAY THROUGH SUNDAY...
ENSEMBLES CONTINUE THE DRY THEME INTO THE UPCOMING WEEKEND...WITH
MID-LVL RIDGING PROGGED TO SLIDE OVERHEAD AND AMPLIFY SLIGHTLY
FRI/SAT. THIS WILL LIKELY RESULT IN A CONTINUED MODERATION TO AFTN
TEMPS...POSSIBLY GOING ABOVE CLIMO IN THE UPR 70S TO PERHAPS 80
DEGREES SOUTH OF I-80 FRI/SAT. FOR THE SECOND HALF OF THE WEEKEND
ENSEMBLE SUGGEST THE MID-LVL RIDGE WILL BEGIN TO DISSOLVE AND DRIFT
EAST...WITH THE LONGWAVE PATTERN TURNING MORE SOUTHWESTERLY AS THE
TROUGH ACROSS THE FOUR-CORNERS REGION BEGINS TO PIVOT EAST INTO THE
SOUTHERN PLAINS. AT THIS TIME THOUGH GUIDANCE SUGGESTS PRECIP WILL
REMAIN WEST OF THE FORECAST AREA THRU THE WEEKEND. GIVEN THE DRY
CONDS AND MINIMAL CLOUDS/LGT WINDS...EXPECT OVERNIGHT LOWS TO EASILY
RADIATE INTO THE LOW/MID 50S.
HIGH CONFIDENCE IN THE EXTENDED FORECAST.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* NONE.
JEE/KB
//DISCUSSION...UPDATED 12Z...
HIGH PRESSURE WILL BUILD OVER THE REGION TODAY LEADING TO AN
EXTENDED PERIOD OF QUIET VFR CONDITIONS. NORTH TO NORTHWEST WINDS
WILL SLOWLY BACK TO WEST BY EARLY TO MID AFTERNOON. WIND SPEEDS
WILL REMAIN LIGHT AROUND 7 KT.
A LAKE BREEZE IS POSSIBLE MID TO LATE THIS AFTN BUT EXPECTING IT
TO ONLY IMPACT WINDS AT GYY. IT MAY COME CLOSE TO MDW BUT
THINKING IT WILL STOP JUST EAST OF MDW. AT GYY WINDS WILL BECOME
NE MID THIS AFTN AND THEN VEER TO SW THIS EVENING. COULD SEE A FEW
HOURS OF LIGHT AND VARIABLE WINDS AT GYY. OTHERWISE WINDS ACROSS
THE BOARD REMAIN LIGHT AND SW OVERNIGHT THROUGH TUESDAY MORNING.
JEE
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH CONFIDENCE IN ALL FORECAST ELEMENTS.
JEE/KB
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT THROUGH SUNDAY...VFR.
JEE
&&
.MARINE...
135 AM CDT
FOR THE SMALL CRAFT ADVISORY...EXTENDED THE ADVISORY INTO THIS
AFTERNOON FOR IL AND THIS EVENING FOR IN. WINDS REMAIN HIGH WITH
GUSTS ARND 25 KT AT THE CRIB AND MICHIGAN CITY BUOY. THEREFORE
EXPECTING WAVES TO DIMINISH SLOWER THAN PREVIOUSLY THOUGHT.
HIGH PRESSURE WILL BUILD OVER THE REGION TODAY AND NORTH WINDS WILL
DIMINISH AND BACK TO W OR NW. A LAKE BREEZE IS PSBL OVER COOK COUNTY
THIS AFTN. THE HIGH CONTINUES EAST AND WINDS BECOME SOUTH ON ITS
BACKSIDE TUESDAY AFTERNOON AND EVENING. SOUTH WINDS PERSIST INTO THE
WEEKEND ARND 10 KT OR LESS. THE SOUTHERN HALF OF THE LAKE WILL HAVE
SE TO E WINDS THROUGH THE WEEKEND AS WELL.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 4 PM MONDAY.
SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 10 PM MONDAY.
&&
$$
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
1045 AM CDT Mon Sep 22 2014
.UPDATE...
ISSUED AT 1045 AM CDT MON SEP 22 2014
The forecast generally looks on track today with just very minor
updates to sky grids over eastern IL where few to scattered
cumulus clouds from I-57 east, especially near IN/IL border per
NAM and RUC curule but still mostly sunny skies. Highs in the
upper 60s to around 70F with north winds 5-10 mph.
1028 mb high pressure over nw IL and northern MO late this morning to
settle over central IL tonight and continue fair weather with
temperatures a bit below normal. Temps currently in the upper 50s
and lower 60s should climb about another 10 degrees for highs in
the upper 60s to around 70F this afternoon. Coolest readings over
east central IL.
&&
.SHORT TERM...(Today)
ISSUED AT 341 AM CDT MON SEP 22 2014
High pressure centered over eastern Nebraska will move east into the
area today. This will bring clear skies, dry weather and light
winds. Even with lots of sunshine today, highs are only expected
to reach into the upper 60s to around 70 degrees. GFS MOS guidance
looks several degrees too warm, while the NAM is too cool.
&&
.LONG TERM...(Tonight through Sunday)
ISSUED AT 341 AM CDT MON SEP 22 2014
An extended period of quiet weather throughout the remainder of the
forecast with high pressure building into and remaining in control
of the Midwest. Surface ridge dominating much of the eastern half
of the CONUS and keeping the weather quiet and fair, with slowly
warming temps through the work week. Weak flow under the sfc high
becomes more southerly on Tuesday as the ridge axis shifts slightly
eastward. Warming trend continues with the thermal ridging over
the desert SW slowly advecting into the center of the country and
max temps are just above normals by Thursday. A weak trof brings
some precip to the Plains Wednesday, but the ridge remains in place
and dry air eroding the activity before impacting Central Illinois.
In the extended, the GFS pushes some minor precip into the extreme
SE with an oddly evolving upper pattern beyond day 6. ECMWF
remaining dry and energy aloft without significant flow seeming to
retrograde somewhat under a larger scale ridge. Keeping the
forecast dry for next weekend until the models become a little more
cohesive with their solutions under the pattern shift.
&&
.AVIATION...(For the 12Z TAFS through 12Z Tuesday morning)
ISSUED AT 605 AM CDT MON SEP 22 2014
VFR conditions will continue at all sites next 24 hours. With high
pressure moving into the area, skies will be clear next 24 hours with
light and variable winds.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...07
SHORT TERM...AUTEN
LONG TERM...HJS
AVIATION...AUTEN
AREA FORECAST DISCUSSION
NWS GOODLAND KS
247 PM MDT MON SEP 22 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 123 PM MDT MON SEP 22 2014
18Z WATER VAPOR IMAGERY AND RUC ANALYSIS INDICATED STRONG SHORT
WAVE TROUGH MOVING TOWARDS THE TRI STATE AREA THROUGH NORTHERN
COLORADO. AT THE SFC...TROUGHING NEAR THE KS/CO STATE LINE HAD
RESULTED IN STRONG SOUTHERLY WINDS ACROSS THE WESTERN HALF OF THE
CWA.
MAIN FORECAST CONCERN WILL BE PRECIPITATION CHANCES THROUGH THE
NIGHT AS AFOREMENTIONED STRONG TROUGH SWEEPS ACROSS THE AREA. NEAR
TERM MODELS GENERALLY AGREE THAT ELEVATED MOSTLY WEAK INSTABILITY
WILL GRADUALLY MOVE EAST TONIGHT...BUT NUMERICAL SOLUTIONS SHOWING
A HIGH DEGREE OF VARIABILITY ESPECIALLY WITH RESPECT TO CONVECTIVE
ALLOWING MODELS. HAVE GENERALLY FOLLOWED A CONSENSUS APPROACH
HOLDING HIGHEST POPS ALONG NORTHERN CWA WHICH IS CLOSER TO UPPER
LOW CENTER. MORNING UPSTREAM SOUNDINGS DO SUGGEST ANOMALOUSLY HIGH
PW VALUES AROUND 200 PERCENT OF NORMAL...BUT WITH WEAK
INSTABILITY...MODEL UNCERTAINTY AND SCATTERED NATURE OF CURRENT
PRECIPITATION HAVE KEPT ONLY MODEST PRECIP AMOUNTS.
PRECIP THREAT WILL DIMINISH TOMORROW MORNING AS UPPER TROUGH
DEPARTS AND FRONT STALLS ACROSS SOUTHERN CWA. THIS FRONT MAY
PROVIDE A FOCUS FOR AFTERNOON AND EARLY EVENING STORMS SHOULD CINH
BE OVERCOME.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 247 PM MDT MON SEP 22 2014
AT THE BEGINNING OF THE EXTENDED PERIOD...NUMERICAL GUIDANCE IS
CONSISTENT SHOWING A WEAKENING UPPER LOW OVER SOUTH DAKOTA MOVING
INTO MINNESOTA WITH A TRAILING TROUGH MOVING EAST OVER CENTRAL
AND EASTERN KANSAS. AFTER THAT...MODEL SOLUTIONS DIVERGE RAPIDLY
AS TO THE FATE OF THE UPPER LOW. BY THURSDAY EVENING...GUIDANCE
SHOWS THE UPPER LOW ANYWHERE FROM AMARILLO TX /NAM/ TO ROCHESTER
MN /EC/. THE NAM LOOKS TOO FAR WEST AND TOO FAST WITH SLOWER
EC/GFS PREFERRED. BUT CONFIDENCE IS LOW IN ANY GIVEN MODEL
SOLUTION THROUGH THE ENTIRE EXTENDED PERIOD.
THIS FORECAST PERIOD IS BASED ON A BLEND OF GENERAL MODEL TRENDS
WHICH BASICALLY HAS THE REMAINS OF THE UPPER LOW MORE OVER CENTRAL
AND EASTERN KANSAS WITH OUR AREA TEMPORARILY UNDER THE INFLUENCE
OF THE UPSTREAM UPPER HIGH WHICH STRETCHES FROM THE DAKOTAS TO
COLORADO. SO IN THE TUESDAY NIGHT INTO WEDNESDAY TIME FRAME...
PRECIPITATION CHANCES ARE TRENDED DOWNWARD WEST TO EAST WITH
SOMEWHAT BETTER FORCING ALOFT BEING TO OUR EAST. BY THE END OF THE
WEEK...THE APPROACH OF THE NEXT SYSTEM IS EXPECTED TO INTERACT
WITH THE REMAINS OF THE UPPER LOW AND BRING IT BACK NORTH...BUT
TIMING AND LOCATION IS UNCERTAIN TO SAY THE LEAST.
WEDNESDAY NIGHT THROUGH SATURDAY NIGHT WERE KEPT DRY UNTIL THE
APPROACH OF THE NEXT VIGOROUS UPSTREAM SYSTEM BRINGS ANOTHER SHOT
AT SHRA/TSRA.
TEMPERATURES WILL BE ABOVE NORMAL IN THE 80S MID TO LATE WEEK BUT
AS THE NEXT SYSTEM APPROACHES NEXT WEEKEND...AFTERNOON HIGHS
SHOULD RETURN CLOSER TO NORMAL IN THE 70S WITH ENHANCED POTENTIAL
FOR CLOUD COVER AND SCATTERED PRECIPITATION.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1208 PM MDT MON SEP 22 2014
MAIN CONCERN WILL BE STRONG SOUTHERLY WINDS TODAY FOLLOWED BY
SCATTERED SHOWERS THROUGH THE EVENING HOURS. DO NOT ANTICIPATE
GREATLY REDUCED FLIGHT CATEGORIES DUE TO RATHER HIGH CLOUD BASES
AND FOR THE MOST PART ONLY WEAK INSTABILITY. COULD SEE A PERIOD OF
LOW STRATUS AROUND 12Z BUT CONFIDENCE IN LONG LIVED PERIOD OF
STRATUS IS LOW.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...JRM
LONG TERM...DLF
AVIATION...JRM
AREA FORECAST DISCUSSION
NWS GOODLAND KS
141 PM MDT MON SEP 22 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 123 PM MDT MON SEP 22 2014
18Z WATER VAPOR IMAGERY AND RUC ANALYSIS INDICATED STRONG SHORT
WAVE TROUGH MOVING TOWARDS THE TRI STATE AREA THROUGH NORTHERN
COLORADO. AT THE SFC...TROUGHING NEAR THE KS/CO STATE LINE HAD
RESULTED IN STRONG SOUTHERLY WINDS ACROSS THE WESTERN HALF OF THE
CWA.
MAIN FORECAST CONCERN WILL BE PRECIPITATION CHANCES THROUGH THE
NIGHT AS AFOREMENTIONED STRONG TROUGH SWEEPS ACROSS THE AREA. NEAR
TERM MODELS GENERALLY AGREE THAT ELEVATED MOSTLY WEAK INSTABILITY
WILL GRADUALLY MOVE EAST TONIGHT...BUT NUMERICAL SOLUTIONS SHOWING
A HIGH DEGREE OF VARIABILITY ESPECIALLY WITH RESPECT TO CONVECTIVE
ALLOWING MODELS. HAVE GENERALLY FOLLOWED A CONSENSUS APPROACH
HOLDING HIGHEST POPS ALONG NORTHERN CWA WHICH IS CLOSER TO UPPER
LOW CENTER. MORNING UPSTREAM SOUNDINGS DO SUGGEST ANOMALOUSLY HIGH
PW VALUES AROUND 200 PERCENT OF NORMAL...BUT WITH WEAK
INSTABILITY...MODEL UNCERTAINTY AND SCATTERED NATURE OF CURRENT
PRECIPITATION HAVE KEPT ONLY MODEST PRECIP AMOUNTS.
PRECIP THREAT WILL DIMINISH TOMORROW MORNING AS UPPER TROUGH
DEPARTS AND FRONT STALLS ACROSS SOUTHERN CWA. THIS FRONT MAY
PROVIDE A FOCUS FOR AFTERNOON AND EARLY EVENING STORMS SHOULD CINH
BE OVERCOME.
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 237 AM MDT MON SEP 22 2014
500 MB SHORTWAVE TROUGH WILL BE EAST OF THE FORECAST AREA
THURSDAY...THOUGH EASTWARD PROGRESSION WILL BE SLOW. AS STRONG 500 MB
TROUGH DEVELOPS OVER THE PACIFIC NORTHWEST...MID LEVEL RIDGE WILL
STRENGTHEN OVER THE ROCKY MOUNTAIN STATES. ASSOCIATED SUBSIDENCE AND
DOWNWARD VERTICAL MOTION WILL PRODUCE DRY CONDITIONS OVER THE TRI-
STATE AREA.
EXPECT 500 MB RIDGE TO AMPLIFY OVER THE DAKOTAS FRIDAY IN RESPONSE
TO CONTINUED DEEPENING OF THE PACIFIC NORTHWEST SYSTEM. FURTHER
EAST...A STRENGTHENING RIDGE OVER THE SOUTHEASTERN UNITED STATES WILL
KEEP THE PLAINS SHORTWAVE TROUGH FROM MOVING EAST. MODELS SHOW
EITHER A RETROGRESSION WITH THE LOW OR SECONDARY DEVELOPMENT OF LOW
PRESSURE OVER THE PLAINS. BOTH SOLUTIONS ARE SOMEWHAT UNUSUAL FOR
THIS TIME OF YEAR. FOR NOW...WILL LEAN TOWARDS THE DRIER GFS...BUT
CONFIDENCE IS RATHER LOW.
ATTENTION WILL TURN TO THE PACIFIC NORTHWEST SYSTEM AS IT MOVES
INLAND THROUGH THE WEEKEND. GFS AND ECMWF ARE GETTING MORE IN LINE
WITH ANOTHER...THOUGH GFS IS FASTER WITH THE MAIN FEATURES. BY
SUNDAY THE CENTER OF THE LOW WILL BE OVER THE GREAT BASIN...AND A
SERIES OF SHORTWAVE TROUGHS WILL ADVECT OVER THE ROCKIES/PLAINS
THROUGH THE WEEKEND. ASSOCIATED UPWARD VERTICAL MOTION COULD TRIGGER
THUNDERSTORMS SATURDAY AFTERNOON/EVENING...BUT WILL KEEP THE
FORECAST DRY FOR NOW DUE TO LACK OF MODEL CONSISTENCY IN REGARDS TO
MOISTURE. THERE IS BETTER CHANCE OF THUNDERSTORMS SUNDAY AND SUNDAY
NIGHT AS MAIN LOW CENTER MOVES OVER THE ROCKIES. LEE SIDE
CYCLOGENESIS WILL DEVELOP SUNDAY AFTERNOON...SO LOW LEVEL
CONVERGENCE NEAR THE SURFACE TROUGH AXIS WILL AID IN CONVECTIVE
DEVELOPMENT. EXPECT SIMILAR CONDITIONS MONDAY...SO WILL KEEP
CONVECTIVE CHANCES IN THE FORECAST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1208 PM MDT MON SEP 22 2014
MAIN CONCERN WILL BE STRONG SOUTHERLY WINDS TODAY FOLLOWED BY
SCATTERED SHOWERS THROUGH THE EVENING HOURS. DO NOT ANTICIPATE
GREATLY REDUCED FLIGHT CATEGORIES DUE TO RATHER HIGH CLOUD BASES
AND FOR THE MOST PART ONLY WEAK INSTABILITY. COULD SEE A PERIOD OF
LOW STRATUS AROUND 12Z BUT CONFIDENCE IN LONG LIVED PERIOD OF
STRATUS IS LOW.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...JRM
LONG TERM...MENTZER
AVIATION...JRM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
414 PM EDT MON SEP 22 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 248 PM EDT MON SEP 22 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW NW FLOW ALF OVER
THE GREAT LKS BTWN UPR RDG IN THE PLAINS AND TROF IN ERN NAMERICA.
SFC HI PRES IS MOVING INTO THE MID MS RIVER VALLEY...WITH LLVL WNW
FLOW ON THE NRN FLANK OF THIS FEATURE ADVECTING SOME DRY AIR SHOWN
ON THE 12Z INL RAOB TOWARD UPR MI. THERE WERE SOME CLDS OVER MUCH OF
THE AREA THIS MRNG ASSOCIATED WITH WAD/ISENTROPIC ASCENT BEST SHOWN
ON THE 290K SFC /ABOUT H85/ THIS MRNG...BUT SINCE THE COOLER AIR
UNDER THE TROF IN ERN CANADA IS RETREATING...LINGERING CLD COVER
EARLY THIS AFTN HAS SHIFTED TO MAINLY THE ERN CWA. WITH MORE
SUNSHINE OVER THE W...TEMPS HAVE RISEN ABV NORMAL AND TO 65-70 AWAY
FM THE COOLING INFLUENCE OF THE LKS. LOOKING TO THE W...SKIES ARE
MOCLR THRU MN UNDER H5 HGT RISES/SFC RDG AXIS EXTENDING N FM THE HI
CENTER/DRY AIRMASS WITH PWAT AS LO AS 0.40-0.50 INCH...BUT MORE HI
CLDS ARE SPREADING NE THRU THE NRN PLAINS IN ADVANCE OF A SHRTWV
LIFTING THRU THE CENTRAL ROCKIES.
MAIN FCST CONCERNS IN THE SHORT TERM ARE FOCUSED ON TEMPS WITH DRY
HI PRES EXPECTED TO DOMINATE.
TNGT...WITH SFC HI PRES RDG MOVING OVER THE CWA UNDER RISING HGTS/
DRY AIRMASS...EXPECT MOCLR CONDITIONS. DESPITE THE DRYNESS OF THE
INCOMING AIRMASS...THE WARMTH OF THIS AIR WITH H85 TEMPS FCST NEAR
12C AT 12Z TUE AS WELL AS STEADY WNW H925 WINDS UP TO 15-20 KTS WL
KEEP TEMPS FM FALLING AS LO AS LAST NGT. EXPECT THE LOWEST MIN TEMPS
OVER THE INTERIOR SCENTRAL CLOSER TO THE LIGHTER H925 WINDS
ASSOCIATED WITH HI PRES CENTER PASSING NEAR THE LOWER LKS. BUT TEMPS
WL NOT FALL BLO 40...SO THERE WL BE NO FROST.
TUE...AS THE SFC HI SHIFTS INTO THE MID ATLANTIC STATES...THE LLVL
FLOW IS FCST TO BACK TO THE SSW. WITH PLENTY OF SUNSHINE UNDER
LINGERING DRY AIRMASS AND H85 TEMPS HOLDING ARND 12C...EXPECT TEMPS
TO TOP OUT IN THE 70S AWAY FM LK MODERATION...WHICH WL OCCUR MAINLY
DOWNWIND OF LK MI. BUT RELATIVELY WEAK PRES GRADIENT FCST OVER THE
UPR LKS...THERE WL BE SOME LK BREEZE FORMATION/LOCAL COOLING NEAR LK
SUP.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 410 PM EDT MON SEP 22 2014
MUCH OF THIS PERIOD WILL REMAIN DRY. EXPECT HIGHS IN THE MID 60S TO
MID 70S THROUGH AT LEAST SUNDAY...WHICH IS AROUND 5-10F ABOVE NORMAL
FOR THIS TIME OF YEAR. AT THE SFC...THE HIGH OVER MUCH OF THE NE
THIRD OF THE NATION WILL KEEP A RIDGE EXTENDED ACROSS THE UPPER
GREAT LAKES THROUGH THE START OF THE WEEKEND.
AT 00Z WEDNESDAY THE UPPER GREAT LAKES WILL BE DIRECTLY UNDER A
500MB RIDGE...WITH A CUT OFF LOW OVER THE DAKOTAS. EXPECT THE 500MB
LOW TO OPEN UP BACK INTO THE MAIN FLOW...AND SETS UP A TROUGH ACROSS
MN ON WEDNESDAY...BEFORE PUSHING ACROSS UPPER MI WEDNESDAY NIGHT
INTO THURSDAY. THE RESULT ACROSS UPPER MI WILL BE A PARTLY TO MOSTLY
CLOUDY SKY FROM W AFTERNOON THROUGH MUCH OF THURSDAY...PRIMARILY
ACROSS THE W HALF. THE 500MB RIDGE WILL QUICKLY BUILD BACK OVERHEAD
ON FRIDAY...EXTENDING FOR BASICALLY ALL BUT THE PACIFIC NW AND THE
NEW ENGLAND STATES.
WITH GENERALLY LIGHT WINDS AND FEW CLOUDS EACH NIGHT...WENT TOWARD
THE LOWER END OF FCST GUIDANCE FOR MORNING LOWS. AND WITH
PREDOMINANT S WINDS EACH DAY...THE DOWNSLOPE WAS PLAYED UP A BIT
MORE NEAR LAKE SUPERIOR...WITH SOME OF THE TRADITIONAL SITES BEING
INCREASED 1-4F.
SUNDAY NIGHT THROUGH MONDAY BECOME A BIT MORE TRICKY WX/WIND
WISE...WITH A SFC TROUGH SINKING IN FROM THE N. LIMITED MOISTURE
AGAIN MAY BE LIMITED. WENT WITH A CONSENSUS SOLUTION...WITH SLIGHT
CHANCE POPS COMING BACK INTO THE FCST FOR MONDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 124 PM EDT MON SEP 22 2014
EXPECT VFR CONDITIONS TO PREVAIL THIS TAF PERIOD WITH DRY HI PRES
DOMINATING. STRONGER W WINDS THIS AFTN WL DIMINISH THIS EVNG WITH
LOSS OF DAYTIME HEATING/MIXING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 248 PM EDT MON SEP 22 2014
W WINDS UP TO 25 KTS INTO THIS EVENING OVER THE NCENTRAL LAKE WILL
DIMINISH OVERNIGHT WITH THE ARRIVAL OF A WEAKER PRES GRADIENT.
WITH THIS RELATIVELY WEAK PRES GRADIENT DOMINATING THE UPPER GREAT
LAKES THRU THE WEEK AND COOL LAKE WATERS/HI STABILITY...EXPECT WINDS
NO HIER THAN 20 KTS INTO THIS WEEKEND.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
252 PM EDT MON SEP 22 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 248 PM EDT MON SEP 22 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW NW FLOW ALF OVER
THE GREAT LKS BTWN UPR RDG IN THE PLAINS AND TROF IN ERN NAMERICA.
SFC HI PRES IS MOVING INTO THE MID MS RIVER VALLEY...WITH LLVL WNW
FLOW ON THE NRN FLANK OF THIS FEATURE ADVECTING SOME DRY AIR SHOWN
ON THE 12Z INL RAOB TOWARD UPR MI. THERE WERE SOME CLDS OVER MUCH OF
THE AREA THIS MRNG ASSOCIATED WITH WAD/ISENTROPIC ASCENT BEST SHOWN
ON THE 290K SFC /ABOUT H85/ THIS MRNG...BUT SINCE THE COOLER AIR
UNDER THE TROF IN ERN CANADA IS RETREATING...LINGERING CLD COVER
EARLY THIS AFTN HAS SHIFTED TO MAINLY THE ERN CWA. WITH MORE
SUNSHINE OVER THE W...TEMPS HAVE RISEN ABV NORMAL AND TO 65-70 AWAY
FM THE COOLING INFLUENCE OF THE LKS. LOOKING TO THE W...SKIES ARE
MOCLR THRU MN UNDER H5 HGT RISES/SFC RDG AXIS EXTENDING N FM THE HI
CENTER/DRY AIRMASS WITH PWAT AS LO AS 0.40-0.50 INCH...BUT MORE HI
CLDS ARE SPREADING NE THRU THE NRN PLAINS IN ADVANCE OF A SHRTWV
LIFTING THRU THE CENTRAL ROCKIES.
MAIN FCST CONCERNS IN THE SHORT TERM ARE FOCUSED ON TEMPS WITH DRY
HI PRES EXPECTED TO DOMINATE.
TNGT...WITH SFC HI PRES RDG MOVING OVER THE CWA UNDER RISING HGTS/
DRY AIRMASS...EXPECT MOCLR CONDITIONS. DESPITE THE DRYNESS OF THE
INCOMING AIRMASS...THE WARMTH OF THIS AIR WITH H85 TEMPS FCST NEAR
12C AT 12Z TUE AS WELL AS STEADY WNW H925 WINDS UP TO 15-20 KTS WL
KEEP TEMPS FM FALLING AS LO AS LAST NGT. EXPECT THE LOWEST MIN TEMPS
OVER THE INTERIOR SCENTRAL CLOSER TO THE LIGHTER H925 WINDS
ASSOCIATED WITH HI PRES CENTER PASSING NEAR THE LOWER LKS. BUT TEMPS
WL NOT FALL BLO 40...SO THERE WL BE NO FROST.
TUE...AS THE SFC HI SHIFTS INTO THE MID ATLANTIC STATES...THE LLVL
FLOW IS FCST TO BACK TO THE SSW. WITH PLENTY OF SUNSHINE UNDER
LINGERING DRY AIRMASS AND H85 TEMPS HOLDING ARND 12C...EXPECT TEMPS
TO TOP OUT IN THE 70S AWAY FM LK MODERATION...WHICH WL OCCUR MAINLY
DOWNWIND OF LK MI. BUT RELATIVELY WEAK PRES GRADIENT FCST OVER THE
UPR LKS...THERE WL BE SOME LK BREEZE FORMATION/LOCAL COOLING NEAR LK
SUP.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 220 AM EDT MON SEP 22 2014
AN UPPER RIDGE BUILDING OVER THE REGION ON TUESDAY WILL REMAIN IN
PLACE THROUGH THE BEGINNING OF NEXT WEEK. THIS WILL LEAD TO DRY
CONDITIONS ACROSS MUCH OF THE UPPER GREAT LAKES REGION. THE ONLY
ITEM OF CONCERN IS AN UPPER WAVE MOVING THROUGH THE ROCKIES AT THIS
TIME. AS IT MOVES INTO THE NORTHERN/CENTRAL PLAINS...THE NORTHERN
HALF OF THE DISTURBANCE IS CLOSE ENOUGH TO A WAVE MOVING THROUGH
CENTRAL CANADA TO BECOME CAUGHT UP IN THE FLOW AND SEPARATED OUT
FROM THE REST OF THE FEATURE. MODELS STILL CONSISTENT ON THE BEST
MOISTURE AND UPPER LEVEL ENERGY SLIDING NORTHEAST JUST TO THE WEST
OF THE CWA. THUS...WILL KEEP THE SLIGHT CHANCE POPS CONFINED TO THE
WEST OF THE CWA WEDNESDAY AFTERNOON INTO WEDNESDAY EVENING...WITH
MOSTLY CLOUDY SKIES OVER WESTERN UPPER MICHIGAN.
OTHERWISE...IT WILL BE A PLEASANT END TO SEPTEMBER ACROSS THE
AREA WITH A SURFACE HIGH STATIONED OVER THE NORTHEAST CONUS. THIS
WILL LEAD TO LIGHT SOUTHERLY FLOW OVER THE UPPER GREAT LAKES
REGION (AROUND A RIDGE STRETCHING NORTHWEST OVER THE AREA) AND ALLOW
FOR ABOVE NORMAL TEMPERATURES THROUGH THE LONG TERM PERIOD. HIGHS
MOST DAYS LOOK TO BE IN THE UPPER 60S TO LOWER 70S (OR ABOUT 5-10
DEGREES ABOVE NORMAL). THERE ARE INDICATIONS THE UPPER RIDGE WILL
BREAK DOWN AROUND THE MIDDLE OF NEXT WEEK (AS THE UPPER TROUGH OVER
THE WESTERN CONUS SHIFTS EAST)...WHICH WILL MARK THE RETURN TO MORE
UNSETTLED WEATHER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 124 PM EDT MON SEP 22 2014
EXPECT VFR CONDITIONS TO PREVAIL THIS TAF PERIOD WITH DRY HI PRES
DOMINATING. STRONGER W WINDS THIS AFTN WL DIMINISH THIS EVNG WITH
LOSS OF DAYTIME HEATING/MIXING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 248 PM EDT MON SEP 22 2014
W WINDS UP TO 25 KTS INTO THIS EVENING OVER THE NCENTRAL LAKE WILL
DIMINISH OVERNIGHT WITH THE ARRIVAL OF A WEAKER PRES GRADIENT.
WITH THIS RELATIVELY WEAK PRES GRADIENT DOMINATING THE UPPER GREAT
LAKES THRU THE WEEK AND COOL LAKE WATERS/HI STABILITY...EXPECT WINDS
NO HIER THAN 20 KTS INTO THIS WEEKEND.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1230 PM CDT MON SEP 22 2014
.UPDATE...
ISSUED AT 1026 AM CDT MON SEP 22 2014
UPDATE TO THE FORECAST TO ACCOUNT FOR THE BAND OF LIGHT
RAIN SHOWERS CURRENTLY ACROSS NORTHEAST COLORADO...THIS BAND IS
LIFTING TO THE NORTHEAST AND WILL IMPACT SOUTHWEST NEBRASKA AND
THE EASTERN PANHANDLE OVER THE NEXT COUPLE HOURS. PREVIOUS
FORECAST HAD THIS HANDLED WELL...JUST MINOR REVISIONS WERE
IMPLEMENTED. THE 22.14Z RUC13 SEEMS TO BE HANDLING THE CURRENT
SITUATION WELL AND IS BEING BLENDED WITH THE PREVIOUS FORECAST
WHICH SUGGESTS A SLIGHT DELAY IN QPF OF AN HOUR OR TWO ACROSS
SOUTHWEST NEBRASKA. IN ADDITION...INSTABILITY IS SOMEWHAT LACKING
OVER THIS AREA...THUS SHOWERS SHOULD PREVAIL RATHER THAN STORMS
THIS MORNING...BUT THE MODEL INDICATES A GRADUAL INCREASE WITH THE
INSTABILITY PARAMETERS INTO THE AFTERNOON...THUNDER IS POSSIBLE
THEN.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 401 AM CDT MON SEP 22 2014
TODAY AND TONIGHT...A DEEPENING SFC TROF WILL ADVANCE SOUTHEAST INTO
WRN NEB TODAY AND TONIGHT. SFC WINDS ARE EXPECTED TO INCREASE TO 15
TO 25 MPH WITH GUSTS TO 35 MPH ACROSS NWRN ZONES. WINDS RELAX A BIT
TONIGHT BUT REMAIN STRONG OFF THE SFC. THE LATEST MODEL CONSENSUS
SUGGESTS CLUSTERS OF SHOWERS AND THUNDERSTORMS SHOULD BE UNDERWAY BY
21Z THIS AFTN AS AN UPPER LOW ACROSS IDAHO ADVANCES EAST TOWARD AND
INTO WRN SD TODAY AND TONIGHT.
THE SEVERE WEATHER POTENTIAL LOOKS LOW TODAY AND TONIGHT AS THE
BETTER INSTABILITY REMAINS OVER ERN COLO. THE MODEL CONSENSUS
SUGGESTS 1/4 TO 1/2 INCH OF RAIN TODAY AND TONIGHT ACROSS THE FCST
AREA BUT THERE IS CERTAINLY THE POTENTIAL FOR MORE GIVEN PWS
INCREASING TO 1.33 INCHES WHICH IS 200 PERCENT OF NORMAL. THE NAM
INDICATED HIGHER VALUES.
THE ONGOING CLOUD COVER ACROSS WRN NEB IS EXPECTED TO INCREASE AND
EXPAND EAST TODAY. SOME CLEARING MAY DEVELOP IN THE WEST LATE
TONIGHT. GIVEN THE HIGH MOISTURE AVAILABLE POPS ARE LIKELY SOUTH AND
EAST TONIGHT.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 401 AM CDT MON SEP 22 2014
THE PRIMARY FORECAST CONCERN WILL BE THUNDERSTORM CHANCES
TUESDAY...THEN WITH TEMPERATURES AND RAIN CHANCES WITH A
RETROGRADING UPPER LEVEL SYSTEM THROUGHOUT THIS WEEK.
TUESDAY...THE UPPER LEVEL LOW WILL BE PUSHING OUT OF THE ROCKY
MOUNTAINS AND INTO THE NORTHERN PLAINS. THE MODELS ARE IN GOOD
AGREEMENT WITH THE UPPER LOW CENTER MOVING ACROSS SOUTH DAKOTA
THROUGH THE DAY...WITH VARIOUS WEAK SHORTWAVE IMPULSES MOVING AROUND
THE SYSTEM.
SHOWERS AND POTENTIALLY A FEW ISOLATED THUNDERSTORMS SHOULD BE
EXITING THE FORECAST AREA TO THE EAST DURING THE MORNING HOURS. BY
AFTERNOON...A SURFACE TROUGH WILL MAKE ITS WAY ACROSS THE PANHANDLE
AND INTO WESTERN NEBRASKA. FORECAST SOUNDINGS SHOW LOCATIONS
GENERALLY WEST OF HIGHWAY 83 WILL MIX OUT AND WITH STEEP LOW LEVEL
AND MID LEVEL LAPSE RATES...CAPE VALUES INCREASE TO 1000-2000 J/KG
BY LATE AFTERNOON AND WITH THE STRONG WARMING...SURFACE BASED
CONVECTION IS LIKELY. THERE IS SOME DISCREPANCIES BETWEEN MODELS IN
TERMS OF DEEP LAYER SHEAR...AS THE GFS IS MUCH STRONGER...SUGGESTING
IN EXCESS OF 40KTS...WHILE THE NAM IS 20 TO 30KTS. EVEN WITH THE
LOWER SHEAR...IT SHOULD BE SUFFICIENT FOR AT LEAST A FEW STRONGER
STORMS LATER TUESDAY AFTERNOON. AREAS TO THE EAST WILL SEE COOLER
HIGHS...IN THE UPPER 60S AND LOW 70S DUE TO THE PRECIPITATION
EARLIER IN THE DAY AND ARE LOOKING TO STAY VERY CAPPED. THESE AREAS
WILL STILL SEE STORMS MOVE IN DURING THE EVENING AND OVERNIGHT
HOURS...BUT THEY SHOULD BECOME ELEVATED QUICKLY AND WITH A LACK OF
INSTABILITY WOULD EXPECT THUNDER TO DECREASE...BUT THERE WILL BE AT
LEAST A WEAK LOW LEVEL JET THAT COULD CONTINUE TO FEED THE STORMS
THROUGH THE NIGHT AS THEY MOVE EAST.
AT 12Z WEDNESDAY MORNING...THE MODELS HAVE MOVED THE UPPER LOW
CENTER OVER SOUTHEAST SOUTH DAKOTA AND NORTHEAST NEBRASKA...AND WITH
THE UPWARD FORCING SHIFTING TO THE EAST...PRECIPITATION SHOULD BE
CLOSE TO...IF NOT COMPLETELY FINISHED LOCALLY. FAIRLY STRONG
SUBSIDENCE BUILDS IN ACROSS THE FORECAST AREA THROUGH THE DAY
WEDNESDAY BEHIND THE UPPER LEVEL SYSTEM LEADS TO A DRY FORECAST.
WARMER AIR WILL BE ADVECTING INTO THE AREA DURING THE DAY AND WITH
THE DRY AIR IN PLACE AND PLENTY OF SUNSHINE...STRONG WARMING IS
EXPECTED WITH HIGHS IN THE 80S FOR THE WESTERN TWO-THIRDS OF THE
FORECAST AREA. WITH THE UPPER LOW REMAINING OVER EASTERN
NEBRASKA...THE EASTERN PARTS OF THE FORECAST AREA MAY SEE SOME
RESIDUAL CLOUD COVER AND WITH COOLER TEMPERATURES ALOFT...WILL SEE
COOLER TEMPERATURES WITH HIGHS LOOKING TO BE IN THE MID TO UPPER 70S.
BEYOND WEDNESDAY THERE BEGINS TO BE SLIGHT DIVERGENCE IN THE MODEL
SOLUTIONS IN TERMS OF THE UPPER LEVEL PATTERN. WHAT IS IN GOOD
AGREEMENT IS A DEEP LONGWAVE TROUGH MOVING INTO THE WESTERN
CONUS...WITH RIDGING BUILDING AHEAD OF IT INTO THE NORTHERN
PLAINS. WHAT IS STARTING TO GET PROBLEMATIC IS THE CURRENT SYSTEM
GETS STUCK UNDER THE LARGE RIDGE WHICH SPANS INTO THE EASTERN PART
OF THE COUNTRY AND STARTS TO RETROGRADE. THE DISCREPANCIES LIE
WITH HOW FAR WEST IT WILL MAKE IT. THE RIDGE TO THE WEST WILL KEEP
SOUTHERLY FLOW IN THE LOWER LEVELS...KEEPING LOW LEVEL MOISTURE
ACROSS THE FORECAST AREA WITH DEWPOINTS REMAINING IN THE UPPER 50S
AND 60S...WHILE WEAK AND MINI SHORTWAVES MAY MOVE ACROSS THE FORECAST
AREA AT TIMES LATER IN THE WEEK. THESE SMALL IMPULSES OF ENERGY
AREN/T LOOKING TO GENERATE ENOUGH LIFT AT THIS POINT TO PROVIDE A
NEED FOR RAIN IN THE FORECAST SO WILL KEEP A DRY FORECAST AT THIS
TIME. WHAT THIS WILL MEAN IS LIKELY COOLER TEMPERATURES FOR LATE
IN THE WEEK AS THE WARMER AIR WILL BE KEPT TO THE WEST AND NORTH
OF THE LOCAL AREA DUE TO THE INFLUENCE OF THE UPPER LEVEL SYSTEM.
THEN LOOKING INTO THE WEEKEND...OUT OF THE LONGWAVE TROUGH MOVING
ONTO THE WEST COAST...A LOW WILL CLOSE OFF AND SLOWLY MIGRATE
TOWARDS THE EAST. THERE IS DIFFERENCES WITH THE SPEED AS THE
OPERATIONAL GFS IS FASTER THAN THE ECMWF AS WELL AS THE GFS
ENSEMBLE MEAN. THE FASTER SOLUTION WOULD BRING CHANCES FOR SHOWERS
AND THUNDERSTORMS BY SUNDAY AFTERNOON...WHILE THE SLOWER WOULD
KEEP THINGS DRY INTO MONDAY. WILL BE KEEPING A CLOSE EYE ON THIS
SYSTEM AS TIME GETS CLOSER TO GET A BETTER HANDLE ON THE FORECAST
FOR THESE PERIODS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1230 PM CDT MON SEP 22 2014
FORECAST CONFIDENCE IN TIMING...DURATION...AND INTENSITY OF THE
EXPECTED PRECIPITATION TODAY/TONIGHT IS LOWER THAN AVERAGE...WITH
THAT BEING SAID...A LEAD DISTURBANCE WILL CONTINUE TO MOVE TO THE
NORTHEAST THIS AFTERNOON ACROSS WESTERN NEBRASKA...POTENTIALLY
SPREADING RAIN SHOWERS...POSSIBLY WITH EMBEDDED RUMBLES OF THUNDER
TO BOTH THE KVTN AND KLBF TERMINALS. AT THIS TIME THERE LOOKS TO BE
NO MAJOR DISRUPTIONS IN VISIBILITY OR CEILINGS THIS AFTERNOON AND
EARLY EVENING...BUT THE CONTINUED INCREASE IN LOWER ATMOSPHERIC
MOISTURE MAY ALLOW FOR MVFR OR LOWER LATE THIS EVENING OR OVERNIGHT.
FORECAST UPDATES MAY BE NEEDED...AND ARE ANTICIPATED. OTHERWISE
THE MAIN UPPER LEVEL LOW WILL EJECT TOWARD THE NORTHERN PLAINS
OVERNIGHT...KEEPING UNSETTLED CONDITIONS IN THE REGION THROUGH THE
ENTIRE FORECAST CYCLE...AT A MINIMUM CEILING SHOULD FALL TO MVFR
OR LOWER AT BOTH TERMINALS AFTER 09Z TOMORROW...BUT RAIN IS ALSO A
POSSIBILITY. WINDS WILL REMAIN GUSTY TODAY AND FROM THE
SOUTH...WEAKEN SLIGHTLY OVERNIGHT...BUT THEN ARE ANTICIPATED TO
INCREASE ONCE AGAIN LATE IN THE FORECAST PERIOD.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JACOBS
SHORT TERM...CDC
LONG TERM...BROOKS
AVIATION...JACOBS
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1155 AM MDT MON SEP 22 2014
.UPDATE...
ISSUED AT 1113 AM MDT MON SEP 22 2014
TWO DISTINCT AREAS OF RAIN ARE CURRENTLY MOVING OVER THE CWA. ONE
IS ACROSS THE NEBRASKA PANHANDLE WITH GENERALLY LIGHT RAIN
OBSERVED AND NO LIGHTNING. THE OTHER IS TO THE WEST OF THE LARAMIE
RANGE CLOSER TO THE MIDLVL LOW CENTER AND THERE IS ISOLATED
EMBEDDED TSTMS. THE QUESTION THIS AFTN IS HOW MUCH CLEARING AND
INSTABILITY WILL BE PRESENT OVER THE PLAINS. BOTH THE GFS AND NAM
SHOW LI VALUES OF AROUND -3C TO -4C ALONG THE WY-NE BORDER AND
EASTWARD INTO THE PANHANDLE AT 00Z. COMBINED WITH MODEST DEEP
LAYER SHEAR (AROUND 30 KTS) COULD SEE SOME STRONGER STORMS WITH
SMALL HAIL. THE HRRR ALSO INDICATES A FEW HIGHER REFLECTIVITY
CORES DEVELOPING IN THE SOUTHERN PANHANDLE AFTER 23Z. THUS...ADDED
THE MENTION OF SMALL HAIL INTO THE GRIDS FOR MUCH OF THE PANHANDLE
AND FAR EASTERN LARAMIE COUNTY DURING THE AFTN AND EARLY EVENING.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 322 AM MDT MON SEP 22 2014
A FEW SHOWERS MOVING NORTHEAST ACROSS NORTHERN COLORADO BUT HAVING
SOME TROUBLE SURVIVING OFF THE MOUNTAINS SO FAR. MEANWHILE AN
UPPER LOW CURRENTLY AROUND THE UTAH/IDAHO BORDER WILL MOVE
NORTHWARD THIS MORNING THEN TURN MORE EASTWARD THROUGH THIS
EVENING EMERGING OVER THE NORTHERN HIGH PLAINS TONIGHT. AN IMPULSE
ROTATING AROUND THE UPPER LOW WILL SWING ACROSS THE CWA THIS
AFTERNOON AND EVENING WITH SCTD SHOWERS AND TSTRMS ASSOCIATED WITH
IT. INSTABILITY WILL BE RATHER WEAK ACROSS MUCH OF THE CWA THIS
AFTERNOON BUT A TONGUE OF BETTER INSTABILITY/CAPES 500-100 J/KG/
LOOKS TO NOSE UP OUT OF COLORADO INTO MAINLY THE SOUTHERN
PANHANDLE INTO THIS EVENING WHICH WITH MARGINAL SHEAR MAY ALLOW
FOR A FEW STRONGER STORMS THERE. ACTIVITY WILL MOVE OUT OF THE CWA
TONIGHT AS THE UPPER IMPULSE SWINGS EAST OF THE AREA AND A WEAK
PACIFIC FRONT MOVES OUT ACROSS THE HIGH PLAINS. MAINLY DRY AND
WARM TUESDAY THOUGH ANOTHER MODEST SHORTWAVE CLIPPING NORTHEAST
PARTS OF THE CWA MAY SET OFF A FEW SHOWERS/TSTMS OVER THAT AREA
TUESDAY AFTERNOON. DRY AND WARMER WEDS AS AN UPPER RIDGE AMPLIFIES
AND BUILDS NORTHEAST ACROSS THE NORTHERN AND CENTRAL ROCKIES.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 322 AM MDT MON SEP 22 2014
SHARP UPPER LEVEL RIDGING BUILDS INTO THE AREA WEDNESDAY NIGHT
INTO THURSDAY. 700MB TEMPERATURES RESPOND AS WELL...CLIMBING TO
+14C AND EVEN +16C ACROSS PORTIONS OF SOUTHERN CARBON AND ALBANY
COUNTIES THURSDAY AFTERNOON. THIS IS UP FROM +10C TO +12C
WEDNESDAY AFTERNOON. AS A RESULT...TEMPERATURES SHOULD BE WARMER
AND ALMOST SUMMER LIKE WITH 90S IN THE PANHANDLE AND MID 80S OUT
WEST. GOING TO BE DRY THROUGH AT LEAST FRIDAY AS WELL WITH SUNNY
SKIES AND LIGHT WINDS.
WEATHER BEGINS TO CHANGE SOME FRIDAY NIGHT INTO SATURDAY. MODELS
INITIALLY IN GOOD AGREEMENT WITH A PACIFIC LOW PRESSURE SYSTEM
MOVING INTO NEVADA OVERNIGHT FRIDAY. GFS MUCH FASTER...BY ROUGHLY
12 TO 18 HOURS ON THE EASTWARD MOVEMENT OF THIS LOW. NEW ECMWF
SLOWER AND HAS THE LOW NOT MOVING INTO NEVADA UNTIL SATURDAY
NIGHT/SUNDAY MORNING. GFS SOLUTION WOULD HAVE FAIRLY WIDESPREAD
SHOWER ACTIVITY FOR AREAS ALONG AND WEST OF THE LARAMIE RANGE
SATURDAY NIGHT INTO SUNDAY. ECMWF SOLUTION HAS SHOWERS MOVING INTO
CARBON COUNTY SUNDAY NIGHT INTO MONDAY. DID A BLEND OF THE TWO
MODELS FOR POPS OVER THE WEEKEND WITH LOW CHANCE POPS SATURDAY
NIGHT. BEST CHANCES LOOK TO BE THROUGH THE DAY SUNDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY MORNING)
ISSUED AT 1145 AM MDT MON SEP 22 2014
AVIATION CONCERNS ARE FOCUSED IN THE FIRST 6-12 HOURS OF THE
TERMINAL AS AN AREA OF LOW PRESSURE PUSHES THROUGH. 17-18Z RADAR
RETURNS SHOW FIRST BAND OF RAIN SHOWERS LIFTING ACROSS THE WRN
NEBRASKA PANHANDLE SITES...WITH THE 2ND PRECIP BAND APPROACH KLAR.
PREDOMINATED THE INITIAL BAND OF PRECIP AT KAIA AND KCDR. THE 2ND
BAND OF PRECIP WILL INCREASE IN COVERAGE AND INTENSITY THE AIR
MASS DESTABILIZES THIS AFTERNOON. AS SUCH...WAS CONFIDENT ENOUGH
TO ADD A TEMPO GROUP TO KLAR...WITH VCTS ELSEWHERE. WILL
UNDOUBTEDLY NEED TO ADD SOME TEMPO GROUPS TO OTHER SITES EAST OF
THE PLAINS THIS AFTERNOON...HOWEVER LESS CONFIDENT ON TIMING AND
PLACEMENT AT THIS TIME. LOW PRESSURE AREA PUSHES EAST OF THE AREA
EARLY TUESDAY...WITH CONDITIONS IMPROVING WEST TO EAST. OUTSIDE OF
THE TEMPO -TSRA GROUP AT KLAR...HAVE KEPT AREA TERMINALS VFR AT
THIS POINT...WITH THE EXPECTATION THAT THESE SOME AREAS WILL SEE
MVFR VSBYS IN HEAVIER SHOWERS/STORMS THIS AFTERNOON.
&&
.FIRE WEATHER...
ISSUED AT 322 AM MDT MON SEP 22 2014
NO SIGNIFICANT CONCERNS EXPECTED THROUGH AT LEAST MIDWEEK WITH MIN
RELATIVE HUMIDITIES EXPECTED TO REMAIN ABOVE CRITICAL LEVELS FOR
THE MOST PART. GUSTY WINDS EXPECTED THIS AFTERNOON OVER WESTERN
AREAS THEN LESS WIND ANTICIPATED TUESDAY AND WEDS. SCTD SHOWERS
AND TSTRMS TODAY WITH ACTIVITY MOVING EAST AND OUT OF THE AREA
THIS EVENING.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...FINCH
SHORT TERM...RE
LONG TERM...CLAYCOMB
AVIATION...HAHN
FIRE WEATHER...RE