Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 09/11/14
AREA FORECAST DISCUSSION
NWS TUCSON AZ
935 AM MST TUE SEP 9 2014
.SYNOPSIS...EXPECT DRIER CONDITIONS AND A WARMING TREND THROUGH
THURSDAY WITH THUNDERSTORMS LIMITED TO MAINLY EAST AND SOUTH OF
TUCSON. INCREASING MOISTURE THIS WEEKEND WILL THEN PROVIDE ISOLATED
AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS.
&&
.DISCUSSION...SATELLITE IMAGERY AND SURFACE OBSERVATIONS INDICATE
PARTLY CLOUDY SKIES AT THIS TIME...WITH SCATTERED TO BROKEN LOWER
AND MID-LEVEL CLOUDS ACROSS SE AZ. DEWPOINTS AT LOWER ELEVATIONS
VALID 16Z WERE IN THE 60S F...AND THESE TEMPS WERE NEARLY IDENTICAL
TO 24 HOURS AGO. 09/12Z KTWC SOUNDING PRECIP WATER VALUE OF 1.28
INCHES WAS 0.75 INCH LOWER VERSUS 24 HOURS AGO. THIS SOUNDING WAS
NEARLY SATURATED IN THE SURFACE-750 MB LAYER AND WAS MUCH DRIER
ABOVE 700 MB VERSUS 24 HOURS AGO. 09/12Z UPPER AIR PLOTS DEPICTED
SHORTWAVE TROUGH AXIS EXTENDED FROM SRN IDAHO SWWD INTO SRN
CALIFORNIA WITH NORTH-TO-SOUTH RIDGE AXIS OVER THE CENTRAL CONUS
PLAINS. LIGHT SWLY FLOW ALOFT PREVAILED OVER SE AZ.
09/12Z NAM/GFS...09/12Z UNIV OF AZ WRF-NAM AND 09/12Z RUC HRRR WERE
NEARLY IDENTICAL WITH DEPICTING PRECIP ECHOES AND ANY QPF/S OF
SIGNIFICANCE TO BE MAINLY NORTH OF THIS FORECAST AREA THRU TONIGHT.
THESE SOLUTIONS SEEM REASONABLE GIVEN THE CONSIDERABLY DRIER REGIME
ALOFT. THE INHERITED OFFICIAL FORECAST DEPICTS A CHANCE OF SHOWERS/
TSTMS THRU THIS EVENING ACROSS THE MOUNTAINS...AND ISOLATED COVERAGE
OF SHOWERS/TSTMS MAINLY ACROSS THE LOWER ELEVATIONS FROM TUCSON EWD.
WILL LIKELY REDUCE POPS GENERALLY ABOUT 5-10 PERCENT FOR THIS
AFTERNOON/EVENING BASED ON THE VARIOUS 09/12Z NWP SOLUTIONS. ANY
SHOWERS LATE TONIGHT/EARLY WED MORNING SHOULD OCCUR ACROSS NERN
SECTIONS WITH DRY CONDITIONS ELSEWHERE. HIGH TEMPS THIS AFTERNOON
WILL GENERALLY BE 3-10 DEGS F WARMER VERSUS TEMPS ACHIEVED MON.
&&
.AVIATION...VALID THRU 10/18Z.
DECREASING MOISTURE WILL CONFINE ISOLATED TO SCATTERED -TSRA/-SHRA
TO LOCALES MAINLY EAST AND SOUTH OF KTUS THRU WEDNESDAY MORNING.
OTHERWISE...CLOUD DECKS WILL GENERALLY BE AT 5-9K FT AGL AND SURFACE
WIND WILL BE MAINLY LESS THAN 10 KTS INTO WEDNESDAY MORNING.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...DRIER CONDITIONS WITH A WARMING TREND WILL OCCUR
THROUGH THURSDAY. ISOLATED SHOWERS AND THUNDERSTORMS WILL BE LIMITED
TO MAINLY EAST AND SOUTH OF TUCSON. INCREASING MOISTURE WILL THEN
PROVIDE ISOLATED MAINLY AFTERNOON AND EVENING THUNDERSTORMS BY THIS
WEEKEND. 20-FOOT WINDS WILL GENERALLY BE LIGHT AND TERRAIN DRIVEN.
&&
.PREV DISCUSSION...RAIN CHANCES WILL CONTINUE TO TAPER OFF THROUGH
LATE IN THE WEEK AS THE PACIFIC TROUGH CONTINUES TO SLOWLY MOVE
EAST. BY LATE IN THE WEEK THROUGH EARLY NEXT WEEK...MOISTURE WILL
RETURN FOR A LOW GRADE MONSOON POP FORECAST WITH BASICALLY ISOLATED
THUNDERSTORMS FOR DESERTS/VALLEYS AND SCATTERED STORMS OVER THE
MOUNTAINS. MODELS ARE SUGGESTING ANOTHER TROPICAL SYSTEM PROGGED TO
BE IN THE GENERAL VICINITY OF THE WEST COAST OF THE SOUTHERN BAJA
PENINSULA BY LATE MONDAY. AT THE LEAST IT COULD SPEW SOME MOISTURE
OUR WAY...SO TIME WILL TELL.
HIGH TEMPERATURES AROUND 4 TO 6 DEGS BELOW NORMAL TODAY AND
WEDNESDAY. NEAR NORMAL HIGHS FOR THURSDAY AND THE WEEKEND THROUGH
EARLY NEXT WEEK...BUT FRIDAY SHOULD BE A FEW DEGREES ABOVE NORMAL.
LOW TEMPERATURES 1 TO 2 DEGS ABOVE NORMAL WEDNESDAY AND THURSDAY
MORNINGS...THEN 4 TO 5 DEGS ABOVE NORMAL THEREAFTER.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
FRANCIS
PREVIOUS DISCUSSION...MOLLERE
AREA FORECAST DISCUSSION...UPDATED
NWS PHOENIX AZ
950 PM MST MON SEP 8 2014
.UPDATED...UPDATED AVIATION DISCUSSION...
&&
.SYNOPSIS...
MOISTURE WILL REMAIN IN PLACE ACROSS THE REGION FOR THE NEXT SEVERAL
DAYS...HOWEVER MOST OF THE LIFT IN THE ATMOSPHERE WILL BECOME
FOCUSED OVER NORTHERN ARIZONA. THUS...ONLY SCATTERED SHOWERS AND
THUNDERSTORMS ARE EXPECTED IN SOME AREAS THROUGH TUESDAY...THOUGH
SOME COULD STILL SEE BRIEF PERIODS OF HEAVY RAIN. A GRADUAL DRYING
TREND WILL BEGIN STARTING DURING THE MIDDLE OF THE WEEK AS HIGH
PRESSURE SLOWLY REBUILDS OVER THE REGION.
&&
.DISCUSSION...
CONVECTION CONTINUES ACROSS FAR WESTERN ARIZONA AND SOUTHEAST
CALIFORNIA THIS EVENING. RADAR AND SATELLITE TRENDS INDICATE A FEW
POP UP SHOWERS ARE EXTENDING SOUTHEASTWARD INTO MARICOPA AND PIMA
COUNTIES ALTHOUGH NOTHING THAT FAR SOUTH HAS BECOME WELL ORGANIZED.
STILL...COULD SEE A FEW SPRINKLES OR SHOWERS ACROSS THE METRO
OVERNIGHT. WILL NUDGE POPS UP SLIGHTLY ACROSS PHOENIX THROUGH
TUESDAY MORNING.
MEANWHILE...00Z NAM AND RAP INDICATE SHOWERS WILL BLOSSOM ACROSS
WESTERN ARIZONA AROUND 12Z OR SOONER AS UPPER FLOW BECOMES MORE
ORGANIZED AND WIND SPEEDS INCREASE. GIVEN FAVORABLE UPSLOPE FOR AND
QUITE A BIT OF MOISTURE STILL IN PLACE ACROSS THE REGION...I AM
GOING TO CONTINUE WITH THE FLASH FLOOD WATCH FOR THE FAVORED UPSLOPE
AREAS NORTH/WEST OF PHOENIX THROUGH TUESDAY EVENING.
&&
.PREVIOUS DISCUSSION...
COMPLICATED FORECAST FOR TUESDAY AS MANY COMPETING FEATURES COME
INTO PLAY DRIVING (OR INHIBITING) CONVECTIVE INITIATION AND
COVERAGE. FORCES/ELEMENTS FAVORABLE FOR CONVECTION INCLUDE A
CONTINUATION OF AN ABNORMALLY MOIST ENVIRONMENT (BOUNDARY LAYER
MIXING RATIOS 11-14 G/KG) AND FORCED ASCENT APPROACHING FROM THE
NORTHWEST IN ASSOCIATION WITH ANOTHER WAVE MOVING TOWARDS NORTHWEST
ARIZONA. DETRIMENTAL FACTORS INCLUDE A VERY DISCERNIBLE DRYSLOT
MOVING NORTH ON THE EASTERN SIDE OF THE OLD NORBERT CIRCULATION WEST
OF THE BAJA...AND WARM AIR ADVECTION IN THE MIDLEVELS HELPING REDUCE
OVERALL INSTABILITY. THE VAST MAJORITY OF HIGH RESOLUTION CONVECTIVE
MODELS (WHICH HAVE PERFORMED VERY WELL IN THIS EVENT TO THIS POINT)
REALLY TARGET NORTHWEST ARIZONA EXTENDING SOUTH INTO LA PAZ AND YUMA
COUNTIES AS THE PRIME REAL ESTATE FOR CONVECTIVE COVERAGE.
THEREFORE...HAVE REALLY TRIMMED POPS OVER THE SERN CWA INCLUDING THE
PHOENIX METRO...WHILE FOCUSING 50 PERCENT CHANCES OVER THE
AFOREMENTIONED AREAS.
FOR WEDNESDAY INTO THE WEEKEND...A SLOW DRYING AND WARMING TREND
WILL COMMENCE AS HIGH PRESSURE ALOFT STEADILY BUILDS ACROSS THE AREA
FROM THE WEST. TOTAL MOISTURE WILL RATHER SLOW TO ERODE AS LOW/MID
LEVEL WIND FIELDS WILL BE ON THE WEAK SIDE...HOWEVER NOTABLE DRY AIR
SEEN IN WV IMAGERY OVER THE EAST PACIFIC SHOULD OVERTAKE MUCH OF THE
AREA. HOWEVER...SOME CONVECTION WILL STILL BE POSSIBLE OVER HIGHER
TERRAIN OF SOUTHERN GILA COUNTY...THOUGH UPPER WINDS WILL MOSTLY
FAVOR THE SOUTHWEST WHICH IS AN UNFAVORABLE DIRECTION FOR BRINGING
ANY HIGHER TERRAIN STORMS INTO THE LOWER DESERTS. EXPECT HIGH
TEMPERATURES TO SLOWLY RISE...REACHING TO AROUND SEASONAL NORMAL
VALUES BY ABOUT FRIDAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
STARTING TO SEE SOME ACTIVITY CREEPING INTO THE WEST VALLEY. GOING
TO MENTION VCSH AT ALL TAF SITES OVERNIGHT BUT IT APPEARS THE BEST
AREAS WILL BE IN THE HIGHER TERRAIN TO THE NORTH AWAY FROM THE
TERMINALS. GIVEN THE ABUNDANCE OF MOISTURE IN THE ATMOSPHERE AND
LINGERING BOUNDARIES FROM THIS MONDAY MORNINGS
CONVECTION...CONFIDENCE IN HOW TONIGHT WILL EVOLVE IS LOW. STORMS
SHOULD RE-FIRE TUESDAY AFTERNOON ACROSS THE AREA...VCSH REINTRODUCED
LATE IN THE TAF PERIOD.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
STORMS MORE LIKELY ACROSS AZ THAN SE CA ON TUESDAY BUT I WILL RETAIN
A MENTION OF VCSH AT BLH FOR A FEW HOURS OVERNIGHT...AND AGAIN
DURING THE AFTERNOON. DRIER AIR SHOULD WORK IN FROM THE SOUTHWEST
LATE IN THE TAF PERIOD.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
THURSDAY THROUGH MONDAY.
A GRADUAL DRYING TREND WILL COMMENCE DURING THE MIDDLE OF THE WEEK
AS MOISTURE GETS SCOURED OUT FROM THE NORTHWEST. ANY SHOWER AND
THUNDERSTORM CHANCES WOULD BE VERY SLIGHT...AND PRIMARILY LIMITED TO
THE HIGHER TERRAIN OF GILA COUNTY DURING THE AFTERNOON AND EARLY
EVENING HOURS. AFTERNOON HUMIDITY LEVELS WILL GENERALLY FALL INTO A
15-30 PERCENT RANGE WITH GOOD TO EXCELLENT OVERNIGHT RECOVERY. ASIDE
FROM SOME AFTERNOON UPSLOPE GUSTINESS...WIND SPEEDS WILL REMAIN
RELATIVELY LIGHT.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...FLASH FLOOD WATCH THROUGH TUESDAY EVENING AZZ020>022.
CA...FLASH FLOOD WATCH THROUGH TUESDAY EVENING CAZ030>032.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...LEINS/MO/CB
AVIATION...LEINS
FIRE WEATHER...MO
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
911 PM MST MON SEP 8 2014
.SYNOPSIS...
MOISTURE WILL REMAIN IN PLACE ACROSS THE REGION FOR THE NEXT SEVERAL
DAYS...HOWEVER MOST OF THE LIFT IN THE ATMOSPHERE WILL BECOME
FOCUSED OVER NORTHERN ARIZONA. THUS...ONLY SCATTERED SHOWERS AND
THUNDERSTORMS ARE EXPECTED IN SOME AREAS THROUGH TUESDAY...THOUGH
SOME COULD STILL SEE BRIEF PERIODS OF HEAVY RAIN. A GRADUAL DRYING
TREND WILL BEGIN STARTING DURING THE MIDDLE OF THE WEEK AS HIGH
PRESSURE SLOWLY REBUILDS OVER THE REGION.
&&
.DISCUSSION...
CONVECTION CONTINUES ACROSS FAR WESTERN ARIZONA AND SOUTHEAST
CALIFORNIA THIS EVENING. RADAR AND SATELLITE TRENDS INDICATE A FEW
POP UP SHOWERS ARE EXTENDING SOUTHEASTWARD INTO MARICOPA AND PIMA
COUNTIES ALTHOUGH NOTHING THAT FAR SOUTH HAS BECOME WELL ORGANIZED.
STILL...COULD SEE A FEW SPRINKLES OR SHOWERS ACROSS THE METRO
OVERNIGHT. WILL NUDGE POPS UP SLIGHTLY ACROSS PHOENIX THROUGH
TUESDAY MORNING.
MEANWHILE...00Z NAM AND RAP INDICATE SHOWERS WILL BLOSSOM ACROSS
WESTERN ARIZONA AROUND 12Z OR SOONER AS UPPER FLOW BECOMES MORE
ORGANIZED AND WIND SPEEDS INCREASE. GIVEN FAVORABLE UPSLOPE FOR AND
QUITE A BIT OF MOISTURE STILL IN PLACE ACROSS THE REGION...I AM
GOING TO CONTINUE WITH THE FLASH FLOOD WATCH FOR THE FAVORED UPSLOPE
AREAS NORTH/WEST OF PHOENIX THROUGH TUESDAY EVENING.
&&
.PREVIOUS DISCUSSION...
COMPLICATED FORECAST FOR TUESDAY AS MANY COMPETING FEATURES COME
INTO PLAY DRIVING (OR INHIBITING) CONVECTIVE INITIATION AND
COVERAGE. FORCES/ELEMENTS FAVORABLE FOR CONVECTION INCLUDE A
CONTINUATION OF AN ABNORMALLY MOIST ENVIRONMENT (BOUNDARY LAYER
MIXING RATIOS 11-14 G/KG) AND FORCED ASCENT APPROACHING FROM THE
NORTHWEST IN ASSOCIATION WITH ANOTHER WAVE MOVING TOWARDS NORTHWEST
ARIZONA. DETRIMENTAL FACTORS INCLUDE A VERY DISCERNIBLE DRYSLOT
MOVING NORTH ON THE EASTERN SIDE OF THE OLD NORBERT CIRCULATION WEST
OF THE BAJA...AND WARM AIR ADVECTION IN THE MIDLEVELS HELPING REDUCE
OVERALL INSTABILITY. THE VAST MAJORITY OF HIGH RESOLUTION CONVECTIVE
MODELS (WHICH HAVE PERFORMED VERY WELL IN THIS EVENT TO THIS POINT)
REALLY TARGET NORTHWEST ARIZONA EXTENDING SOUTH INTO LA PAZ AND YUMA
COUNTIES AS THE PRIME REAL ESTATE FOR CONVECTIVE COVERAGE.
THEREFORE...HAVE REALLY TRIMMED POPS OVER THE SERN CWA INCLUDING THE
PHOENIX METRO...WHILE FOCUSING 50 PERCENT CHANCES OVER THE
AFOREMENTIONED AREAS.
FOR WEDNESDAY INTO THE WEEKEND...A SLOW DRYING AND WARMING TREND
WILL COMMENCE AS HIGH PRESSURE ALOFT STEADILY BUILDS ACROSS THE AREA
FROM THE WEST. TOTAL MOISTURE WILL RATHER SLOW TO ERODE AS LOW/MID
LEVEL WIND FIELDS WILL BE ON THE WEAK SIDE...HOWEVER NOTABLE DRY AIR
SEEN IN WV IMAGERY OVER THE EAST PACIFIC SHOULD OVERTAKE MUCH OF THE
AREA. HOWEVER...SOME CONVECTION WILL STILL BE POSSIBLE OVER HIGHER
TERRAIN OF SOUTHERN GILA COUNTY...THOUGH UPPER WINDS WILL MOSTLY
FAVOR THE SOUTHWEST WHICH IS AN UNFAVORABLE DIRECTION FOR BRINGING
ANY HIGHER TERRAIN STORMS INTO THE LOWER DESERTS. EXPECT HIGH
TEMPERATURES TO SLOWLY RISE...REACHING TO AROUND SEASONAL NORMAL
VALUES BY ABOUT FRIDAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
CHANCES OF GETTING ANY ADDITIONAL TS/SHRA INTO TERMINALS THROUGH
TUESDAY MORNING IS UNLIKELY. WHILE VFR CONDITIONS WILL LARGELY
PREVAIL AT THE TERMINAL SITES...LOWER CIGS WILL CONTINUE TO HUG
MOUNTAINS THROUGH THIS EVENING...POTENTIALLY IMPACTING OPERATIONS.
MID/HIGH CLOUDS WILL LINGER INTO TUESDAY...THOUGH GENERALLY AOA 7K
FT. WINDS WILL GENERALLY FAVOR A SOUTHEAST DIRECTION...THOUGH MAY
VEER TO SW FOR A TIME THIS EVENING.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
SOME ISOLD THUNDER MAY BE POSSIBLE ACROSS SERN CALIFORNIA
TERMINALS...THOUGH MOST ACTIVITY SHOULD REMAIN NORTH OF THE SITES.
HAVE INCLUDED A PERIOD OF VCSH AS THE MAJORITY OF LIGHTNING HAS
MOVED NORTH. CLOUD COVERAGE SHOULD REMAIN PREDOMINANTLY SCT AND
ABOVE 6K FT. SFC WINDS WILL FAVOR A SOUTHERLY DIRECTION...BUT MAY
BECOME VARIABLE IN SOME CASES.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
THURSDAY THROUGH MONDAY.
A GRADUAL DRYING TREND WILL COMMENCE DURING THE MIDDLE OF THE WEEK
AS MOISTURE GETS SCOURED OUT FROM THE NORTHWEST. ANY SHOWER AND
THUNDERSTORM CHANCES WOULD BE VERY SLIGHT...AND PRIMARILY LIMITED TO
THE HIGHER TERRAIN OF GILA COUNTY DURING THE AFTERNOON AND EARLY
EVENING HOURS. AFTERNOON HUMIDITY LEVELS WILL GENERALLY FALL INTO A
15-30 PERCENT RANGE WITH GOOD TO EXCELLENT OVERNIGHT RECOVERY. ASIDE
FROM SOME AFTERNOON UPSLOPE GUSTINESS...WIND SPEEDS WILL REMAIN
RELATIVELY LIGHT.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...FLASH FLOOD WATCH THROUGH TUESDAY EVENING AZZ020>022.
CA...FLASH FLOOD WATCH THROUGH TUESDAY EVENING CAZ030>032.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...LEINS/MO/CB
AVIATION...MO
FIRE WEATHER...MO
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
430 AM PDT TUE SEP 9 2014
.SYNOPSIS...
LINGERING MOISTURE WILL BRING A CHANCE OF AFTERNOON THUNDERSTORMS
TODAY...MAINLY TO THE SAN DIEGO COUNTY MOUNTAINS AND DESERTS. DRY
WEATHER WITH SEASONAL TEMPERATURES IS EXPECTED FOR WEDNESDAY AND
THURSDAY. FOR FRIDAY THROUGH MONDAY...HIGH PRESSURE TO THE EAST WILL
EXPAND WESTWARD BRING WARMING WITH HIGH TEMPERATURES WARMING TO 5 TO
10 DEGREES ABOVE AVERAGE WEST OF THE MOUNTAINS. MONSOONAL MOISTURE
MAY RETURN WITH A RENEWED CHANCE OF AFTERNOON AND EVENING
THUNDERSTORMS FOR SUNDAY AND MONDAY.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
.SHORT TERM (TODAY THROUGH THURSDAY)...
LOWER LEVEL MOISTURE AND HIGH PRECIPITABLE WATER VALUES REMAIN IN
PLACE ACROSS THE LOWER DESERTS AND OTHER SOUTHERN AREAS. VALUES IN
THE LOWER DESERTS REMAIN NEAR 2 INCHES AND VALUES AT POINT LOMA
HAVE RISEN STEADILY IN THE PAST 24 HOURS TO AROUND 2 INCHES AS LOWER
LEVEL MOISTURE ON THE NORTHERN EDGES OF THE REMAINING LOWER LEVEL
CIRCULATION OF WHAT WAS ONCE HURRICANE NORBERT SPREADS ACROSS FAR
SOUTHERN CALIFORNIA THIS MORNING. THIS HAS BROUGHT IN A BROKEN CLOUD
DECK TO SOUTHERN SAN DIEGO COUNTY WITH THE BASES NEAR 3000 FEET MSL.
THE CURRENT PRECIPITABLE WATER VALUES ARE IN LINE WITH THE 08Z RUN
OF THE EXPERIMENTAL NCEP VERSION OF THE HRRR. THE NAM IS LOWER THAN
THE OBSERVED VALUES AND APPEARS TO BE TOO FAST WITH THE DRYING. THE
NCEP HRRR SHOWS CURRENT PRECIPITABLE VALUES BEING MAINTAINED THROUGH
MUCH OF THE MORNING...THEN GRADUALLY DECREASING IN THE LOWER DESERTS
FROM LATE MORNING THROUGH THE AFTERNOON. THE NCEP HRRR KEEPS MOST
CONVECTION THIS AFTERNOON SOUTH OF THE BORDER OVER FAR NORTHERN
BAJA. THE CURRENT FORECAST RETAINS THE SLIGHT CHANCE OF AFTERNOON
THUNDERSTORMS FOR THE SAN DIEGO COUNTY MOUNTAINS AND DESERTS WHERE
THE RESIDUAL LOWER LEVEL MOISTURE AND SEA BREEZE CONVERGENCE MIGHT
BE SUFFICIENT FOR THUNDERSTORM DEVELOPMENT. HIGH TEMPERATURES TODAY
WILL BE NEAR TO SLIGHTLY ABOVE AVERAGE FOR MOST AREAS.
FOR WEDNESDAY AND THURSDAY...DRY WEATHER WITH SEASONAL HIGH
TEMPERATURES IS EXPECTED. SOME PATCHY NIGHT AND MORNING LOW CLOUDS
AND FOG MIGHT RETURN. BUT THE RELATIVELY STRATUS FREE PERIOD WILL
CONTINUE. SEA SURFACE TEMPERATURES ARE CURRENTLY THE WARMEST FOR
THE SUMMER SO FAR...AROUND 76 DEGREES NEAR THE SAN DIEGO COUNTY
COAST. THIS WILL DO LITTLE TO HELP WITH STRATUS FORMATION.
&&
.LONG TERM (FRIDAY THROUGH MONDAY)...
HIGH PRESSURE TO THE EAST WILL EXPAND WESTWARD BRINGING ABOVE
AVERAGE HIGH TEMPERATURES...ESPECIALLY WEST OF THE MOUNTAINS WHERE
CURRENT GUIDANCE WOULD WARM HIGH TEMPERATURES TO 6 TO 12 DEGREES
ABOVE AVERAGE OVER THE WEEKEND. WHILE THIS WILL BE A WARM PERIOD...
CURRENT GUIDANCE MOSTLY KEEPS TEMPERATURES BELOW RECORD LEVELS AND
BELOW HEAT ADVISORY THRESHOLDS EXCEPT POSSIBLY FOR THE INLAND EMPIRE
ON SUNDAY. MONSOONAL MOISTURE MAY RETURN ON SUNDAY AND MONDAY FOR A
RENEWED CHANCE OF AFTERNOON AND EVENING THUNDERSTORMS IN THE
MOUNTAINS AND DESERTS.
CURRENT NHC FORECASTS GIVE THE AREA OF DISTURBED WEATHER OFF THE
SOUTHWEST COAST OF MEXICO AN 80 PERCENT CHANCE OF DEVELOPING INTO A
TROPICAL SYSTEM IN THE NEXT 5 DAYS. CURRENT ECMWF AND GFS FORECASTS
MOVE THIS ON A TRACK SIMILAR TO NORBERT...TO A POSITION OFF THE
SOUTHWEST BAJA COAST EARLY NEXT WEEK. BUT WITH MOVEMENT THEREAFTER
SLOWLY TOWARD THE NORTHWEST OVER COOLER WATERS...ANY IMPACT TO
SOUTHERN CALIFORNIA MIGHT WELL BE LITTLE MORE THAN ENHANCED MONSOON
FLOW SIMILAR TO NORBERT.
&&
.AVIATION...
090930Z...COAST/VALLEYS...OCCASIONAL SCT/BKN CLOUDS BETWEEN
6000-8000 FT MSL WILL CONTINUE THROUGH 09/1800Z THIS MORNING. A
BKN/OVC LOW CLOUD DECK IS NOT EXPECTED TO FORM WEST OF THE MOUNTAINS
TONIGHT...ESPECIALLY WITH THE INFLUENCE OF THE MID LEVEL CLOUDS.
SKC CONDS EXPECTED THROUGH THIS EVENING. STRATUS WILL DEVELOP OVER
THE COASTAL WATERS AND MOVE INLAND 5-10 SM AFT 10/0600Z...ESPECIALLY
OVER SAN DIEGO COUNTY. BASES AROUND 1000 FT MSL AND TOPS 1400 FT
MSL. CONFIDENCE OF STRATUS RETURN IS LOW TO MODERATE.
MTNS/DESERTS...SCT/BKN CLOUDS AT/ABOVE 8000 FT MSL WILL CONTINUE
THROUGH TODAY. THERE IS A SLIGHT CHANCE OF THUNDERSTORMS MAINLY
09/1900Z-10/0100Z...WITH BASES MOSTLY AROUND 8000 FT MSL WITH TOPS
TO 35000 FT MSL. THESE STORMS WILL BE CAPABLE OF PRODUCING LOCAL SFC
WIND GUSTS OVER 40 KNOTS.
&&
.MARINE...
200 AM...NO SIGNIFICANT MARINE WEATHER EXPECTED THROUGH SUNDAY.
&&
.SKYWARN...
SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER SPOTTERS ARE
ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.
&&
$$
PUBLIC...17
AVIATION/MARINE...JT
AREA FORECAST DISCUSSION
NWS PUEBLO CO
ISSUED BY NATIONAL WEATHER SERVICE GOODLAND KS
1228 PM MDT TUE SEP 9 2014
.UPDATE...
ISSUED AT 1038 AM MDT TUE SEP 9 2014
UPDATED TO EXPAND THE FLASH FLOOD WATCH TO INCLUDE MOST
OF THE CONTDVD THROUGH 06Z. CONVECTION DOES NOT LOOK PARTICULARLY
HEAVY FOR LATER TODAY...AND STORM MOVEMENT WILL BE DECENT TO THE
EAST. HOWEVER...DYNAMICS LOOK RESPECTABLE WITH THE TROUGH...AND
HIGH RES MODELS INDICATE SEVERAL WAVES OF MDT-HEAVY PRECIP
CROSSING THE DVD THROUGH THIS EVE. THE MT AREAS WILL
BE SUSCEPTIBLE TO LOCAL FLOODING INCLUDING THE POTENTIAL FOR MUD
OR ROCK SLIDES. IN COORDINATION WITH KGJT WILL MATCH UP OUR WATCH
THROUGH THIS EVE. ROSE
UPDATE ISSUED AT 938 AM MDT TUE SEP 9 2014
UPDATE MAINLY TO RAISE POPS A BIT IN THE SHORT TERM...BASED
ON OBS AND LATEST HI-RES MODELS. ZONAL FLOW ALOFT WILL LIMIT
PRECIP POTENTIAL OVR THE PLAINS TODAY...BUT THERE IS ENOUGH
INSTABILITY AND MOISTURE TO JUSTIFY AT LEAST MENTIONABLE POPS
FOR THE I-25 CORRIDOR THROUGH THIS EVE. HRRR SUGGESTS TWO ROUNDS
OR WAVES OF PRECIP...ONE THIS AFTERNOON PRIMARILY N OF HGWY
50...THEN ANOTHER OVER THE DVD AND PIKES PEAK REGION EARLY THIS
EVE...WITH BOTH ZONES OF PRECIP MOVING EWD AT A DECENT SPEED.
THIS SHOULD HELP LIMIT FLOOD POTENTIAL...BUT WILL HAVE TO WATCH
THE BURN SCARS. GREATEST FLOOD THREAT CONTINUES TO BE OVR THE
CONTDVD THROUGH THIS PERIOD. ROSE
UPDATE ISSUED AT 742 AM MDT TUE SEP 9 2014
BROUGHT IN LATEST OBSERVATIONS AND BLENDED INTO SHORT TERM GRIDS.
NO OTHER CHANGES AT THIS TIME.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 442 AM MDT TUE SEP 9 2014
...DISTURBANCE AND SUBTROPICAL MOISTURE TO MOVE THROUGH TODAY...
AN UPPER LEVEL DISTURBANCE OVER NEVADA THIS MORNING WILL COMBINE
WITH SUBTROPICAL MOISTURE COMING UP ACROSS ARIZONA TO PRODUCE
SCATTERED SHOWERS AND THUNDERSTORMS ACROSS SOUTHERN COLORADO TODAY.
HARDEST HIT WILL BE AREAS ALONG THE CONTINENTAL DIVIDE. A SECONDARY
MAXIMUM OF ACTIVITY WILL LIKELY DEVELOP OVER THE PIKES PEAK REGION
DURING THE AFTERNOON AND EVENING HOURS. ELSEWHERE...SHOWERS AND
THUNDERSTORMS WILL TEND TO BE RATHER SPOTTY.
THE PRIMARY CONCERN TODAY IS THE POTENTIAL FOR LOCALIZED HEAVY RAIN
AND FLASH FLOODING...ESPECIALLY ON BURN SCARS. PROBABLY THE MOST
SUSCEPTIBLE SCAR TODAY WILL BE THE WEST FORK. THUS...THE FLASH
FLOOD WATCH WILL REMAIN IN EFFECT THERE. THE WALDO CANYON AND BLACK
FOREST BURN SCARS PROBABLY HAVE THE SECOND GREATEST RISK TODAY.
HOWEVER...RAINFALL AMOUNTS ARE EXPECTED TO BE A LOT LESS THEN
LOCATIONS FARTHER WEST...SO NO WATCH FOR THOSE AREAS. NEVER THE
LESS...CLOSE MONITORING OF THOSE AREAS WILL CONTINUE FOR THAT
POSSIBLE HIT OR MISS STORM THAT COULD DEVELOP.
TONIGHT...THE AXIS OF THE UPPER LEVEL DISTURBANCE WILL MOVE TO NEAR
THE CONTINENTAL DIVIDE BY WEDNESDAY MORNING. THIS WILL KEEP THE
SHOWER AND THUNDERSTORM THREAT GOING THROUGH MUCH OF THE NIGHT. THE
SOURCE OF THE MOISTURE WILL BE TRANSITIONING OVER FROM SUBTROPICAL
TO PACIFIC SO THE HEAVY RAIN AND FLASH FLOOD THREAT WILL DIMINISH.
AS THE UPPER DISTURBANCE APPROACHES...A COLD FRONT WILL DROP SOUTH
THROUGH THE EASTERN COLORADO PLAINS OVERNIGHT. THE FRONT MAY OR MAY
NOT PRODUCE SOME LIGHT SHOWERS OR ISOLATED THUNDERSTORMS AS IT MOVES
SOUTH THROUGH THE EVENING AND OVERNIGHT HOURS. MODELS HAVE BEEN
BACK AND FORTH ON THIS...WITH THE LATEST RENDITION LEANING MORE
TOWARD NAY RATHER THAN YEA. WILL KEEP SOME LOW CHANCES FOR PRECIP
IN ACROSS THE PLAINS OVERNIGHT TO REFLECT THE POSSIBILITY OF SOME
LIGHT POST FRONTAL PRECIP. LW
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 442 AM MDT TUE SEP 9 2014
...A BIG COOL DOWN FOR THURSDAY NIGHT AND FRIDAY ACROSS EASTERN
COLORADO...
WEDNESDAY-THURSDAY...MODERATE WEST TO NORTHWEST FLOW ALOFT IS
PROGGED ACROSS THE AREA WEDNESDAY...AS AN UPPER TROUGH CONTINUES TO
TRANSLATE ACROSS THE ROCKIES AND INTO THE HIGH PLAINS WEDNESDAY
AFTERNOON. SOME DIFFERENCES ON TIMING OF SAID TROUGH AND ASSOCIATED
COLD FRONT SLIDING DOWN THE EASTERN PLAINS WITH THE GFS AND ECMWF A
TAD SLOWER THAN THE NAM. AT ANY RATE...WITH WAA AHEAD OF THE TROUGH
PASSING SYSTEM AND ITS ASSOCIATED FRONT MOVING ACROSS THE AREA EARLY
WEDNESDAY MORNING...HAVE KEPT SLIGHT POPS IN TACT ACROSS THE EASTERN
MTS AND PLAINS THROUGH THE MORNING...WITH POPS CONFINED TO OVER AND
NEAR THE HIGHER TERRAIN WEDNESDAY AFTERNOON AND EARLY EVENING WITH
THE DEVELOPING UPSLOPE FLOW. TEMPERATURES ACROSS THE AREA TO COOL
INTO THE MID 60S TO MID 70S ACROSS THE LOWER ELEVATIONS AND MAINLY
IN THE 50S AND 60S ACROSS THE HIGHER TERRAIN.
FLOW ALOFT PROGGED TO BECOME MORE WEST TO SOUTHWEST WEDNESDAY NIGHT
AND THURSDAY...AS A STRONGER CANADIAN SYSTEM DIGS INTO THE
NORTHERN ROCKIES...WITH ITS ASSOCIATED COLD FRONT PUSHING ACROSS
THE NORTHERN HIGH PLAINS INTO NORTHEASTERN COLORADO BY LATE
THURSDAY AFTERNOON. SHOULD SEE WARMING ACROSS THE AREA WEDNESDAY
NIGHT AND EARLY THURSDAY WITH THE DOWNSLOPE FLOW ALONG WITH MAINLY
DRY CONDITIONS...SAVE A FEW POSSIBLE WAA SHOWERS...WITH THE BEST
CHANCES OF PRECIPITATION EXPECTED BEHIND FROPA THURSDAY EVENING
AND NIGHT.
THURSDAY NIGHT-FRIDAY...STILL SOME DIFFERENCES ON PLACEMENT OF
COLDEST AIR ASSOCIATED WITH THE CANADIAN SYSTEM...WITH THE GFS STILL
THE WARMEST...BRINGING H7 TEMPS DOWN TO +2C ACROSS THE PIKES PEAK
REGION BY 12Z FRIDAY...WHERE AS THE 00Z EC HAS H7 TEMPS OF -4C AND
THE 06Z NAM NOW HAS H7 TEMPS BETWEEN -2C AND -4C. AT ANY
RATE...SHOULD SEE STRONG FRONTAL PUSH ACROSS THE EASTERN PLAINS
THURSDAY EVENING WITH SOUNDINGS INDICATING LOWER LEVELS QUICKLY
SATURATING BEHIND THE FRONT. THIS ALONG WITH WESTERLY MID LEVEL
WAA...SHOULD ALLOW FOR SCATTERED SHOWERS DEVELOPING ACROSS THE
EASTERN MTS AND PLAINS THURSDAY EVENING AND NIGHT...WITH SHOWERS
DIMINISHING FROM WEST TO EAST THROUGH THE DAY FRIDAY. HAVE CONTINUED
TO TREND TEMPS DOWN THURSDAY NIGHT WITH SOME WET SNOW SHOWERS
POSSIBLE AND TEMPS AT OR SLIGHTLY BELOW FREEZING ACROSS THE TELLER
COUNTY AND NORTHERN PORTIONS OF EL PASO COUNTY AND A COLD RAIN
ACROSS THE REST OF THE PLAINS. HAVE ALSO TRENDED TEMPS SLIGHTLY
DOWNWARD ON FRIDAY...ESPECIALLY ACROSS THE EASTERN PLAINS...WITH
HIGHS MAINLY IN THE 50S (SOME 20-30 DEGREES BELOW SEASONAL NORMS)
WITHIN COOL UPSLOPE FLOW.
FRIDAY NIGHT-MONDAY...A WARMER AND DRIER WEATHER WESTERLY FLOW
PATTERN LOOKS TO BE IN THE OFFING THROUGH THE WEEKEND. THE LATEST
GFS IS A TAD MORE AMPLIFIED INDICATING MORE NORTHWEST FLOW ALOFT AND
A FEW EMBEDDED SHORT WAVE RIPPLING ACROSS THE AREA THROUGH THE
PERIOD. MODEL CONSENSUS KEEPS MAINLY SLIGHT POPS OVER AND NEAR THE
HIGHER TERRAIN THROUGH THE PERIOD...AND TEMPERATURES WARMING BACK TO
AT OR SLIGHTLY ABOVE SEASONAL AVERAGES THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1224 PM MDT TUE SEP 9 2014
MAIN CONCERN WILL BE POTENTIAL FOR BRIEF MVFR-IFR CONDITIONS
DUE TO TSRA LATE THIS AFTERNOON THROUGH EVE. SOME COMPUTER
GUIDANCE SUGGESTS THAT SHOWERS AND ISOLD TS WILL CONTINUE THROUGH
06Z OR LATER FOR VC KCOS...BUT WILL LEAVE MENTION OUOT OF TAF FOR
NOW UNTIL THERE IS BETTER CONSENSUS. WIND SHIFT DUE TO FRONT
SHOULD ARRIVE FROM 21-23Z AT KCOS AND KPUB RESPECTIVELY...WITH
SOME GUSTY N WINDS OCCURRING BEHIND THE FRONT. ROSE
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL MIDNIGHT MDT TONIGHT FOR COZ058>061-
066>068.
&&
$$
UPDATE...ROSE
SHORT TERM...LW
LONG TERM...MW
AVIATION...ROSE
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1124 PM MDT MON SEP 8 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 340 PM MDT MON SEP 8 2014
...LOCALIZED FLASH FLOOD POTENTIAL ALONG THE CONTINENTAL DIVIDE
TONIGHT...
CONVECTION HAS BEEN SLOW TO GET GOING ACROSS THE AREA TODAY...IN
PART BY CLOUD COVER OUT WEST WHICH HAS HINDERED HEATING...AND IN
PART BY FALLING DEW POINTS ACROSS THE I-25 CORRIDOR AND SOUTHEAST
PLAINS WHICH HAS LIMITED CAPE. LOCAL HRRR BREAKS OUT STRONGER
CONVECTION ACROSS THE MOUNTAINS DURING THE LATE AFTERNOON AS WELL AS
ALONG A SFC TROF AXIS ACROSS THE SOUTHEAST PLAINS. OVERALL...CAPES
ARE NOT ALL THAT HIGH...SO THINK THIS CONVECTION WILL BE ON THE WEAK
SIDE. HOWEVER...THERE IS SUFFICIENT MOISTURE IN THE ATMOSPHERE FOR
HEAVY ENOUGH RAINFALL TO CAUSE PROBLEMS FOR BURN
SCARS...PARTICULARLY OUT WEST WHERE THEY ARE STEADILY INCREASING.
INTERESTINGLY...HRRR SEEMS TO BE BACKING OFF ON QPF ACROSS THE
SOUTHWEST MOUNTAINS THIS AFTERNOON BUT NAM12 AND OTHER VARIOUS HIGH
RES MODELS STILL SUGGEST THE THREAT IS THERE.
GREATER THREAT FOR FLASH FLOODING FOR THE SOUTHWEST MOUNTAINS STILL
APPEARS TO COME IN DURING THE OVERNIGHT HOURS AS THE SHORTWAVE
ACROSS EAST CENTRAL AZ LIFTS SLOWING TO THE NORTHEAST INTO NRN NM
OVERNIGHT. ALSO WATCHING A VERY DISCERNIBLE SHORTWAVE ACROSS
WESTERN UT WHICH WILL BE MOVING ACROSS THE AREA AT THE SAME TIME
THAT MONSOON MOISTURE ADVECTS INTO THE SOUTHWEST MOUNTAINS.
PRECIPITABLE WATERS INCREASE TO NEAR AN INCH AT PAGOSA SPRINGS AS H7
WINDS IN THE NAM INCREASE FROM THE SOUTHWEST. THIS COMPONENT
PROVIDES THE MOST FAVORABLE UPSLOPE COMPONENT INTO THE EASTERN SAN
JUAN MOUNTAINS. ALL THIS SHOULD MEAN SHOWERS AND THUNDERSTORMS WILL
EXPAND IN AREAL COVERAGE OVERNIGHT (AFTER 06Z) AS LIFT AND MOISTURE
INCREASE WITH THE INCOMING WAVES. ALTHOUGH THE MODELS PORTRAY
VARIOUS SCENARIOS AS TO WHERE THE QPF MAXIMUM WILL OCCUR...THERE ARE
SUFFICIENT SIGNALS IN THE MODEL DATA TO SUGGEST A HEAVY RAINFALL
POTENTIAL SIGNIFICANT ENOUGH TO WARRANT A FLASH FLOOD WATCH FOR THE
EASTERN SAN JUAN MOUNTAINS WERE UPSLOPE MAY REGENERATE SHOWERS AND
THUNDERSTORMS WHICH COULD TRAIN OVER THE SAME SPOTS AS THEY MOVE OFF
TO THE NORTHEAST. STORM MOTIONS SHOULD BE FAST...BUT REPETITIVE
RAINFALL ON THE SAME LOCATION MAY CAUSE FLASH FLOOD PROBLEMS WITH
THE WEST FORK BURN SCAR BEING MOST UNDER THE GUN. REALLY CAN`T RULE
OUT HEAVY RAIN ANYWHERE ACROSS WESTERN PORTIONS OF THE FORECAST
AREA...BUT THREAT SEEMS HIGHEST ACROSS THE SOUTHWEST MOUNTAINS DUE
TO THE UPSLOPE AND PROXIMITY TO THE BURN SCAR SO WILL LIMIT FLASH
FLOOD WATCH TO THAT AREA FOR NOW.
ONE WAVE OF PRECIPITATION WILL SPREAD EASTWARD ACROSS THE AREA LATE
TONIGHT...WITH SCATTERED SHOWERS SPREADING INTO THE PIKES PEAK
REGION TOWARDS DAWN. THIS INITIAL BATCH STILL LOOKS RATHER LIGHT AS
IT MOVES EAST OF THE CONTDVD...AND QUICKLY SKIRTS OFF TO THE EAST
DURING THE MORNING. THEN THE MAIN PACIFIC TROF MOVES IN DURING THE
AFTERNOON. THIS SHOULD ENHANCE SHOWERS AND THUNDERSTORMS OVER THE
MOUNTAINS AGAIN DURING THE AFTERNOON WHICH WILL KEEP THE THREAT FOR
LOCALIZED FLASH FLOODING GOING ACROSS THE SOUTHWEST MOUNTAINS.
STILL NOT STRONG ENOUGH SIGNALS TO SUGGEST FLASH FLOODING FOR THE
SOUTHEAST MTS/PLAINS. LOW LEVEL WINDS ARE WESTERLY WHICH IS
DOWNSLOPE...AND AS A RESULT...DEW POINTS...WHICH DO INCREASE
SOME...ARE STILL ONLY IN THE 40S. THIS RESULTS IN CAPES OF ONLY A
FEW HUNDRED J/KG DURING THE AFTERNOON. SHOWERS AND THUNDERSTORMS
WILL MOVE OFF THE MOUNTAINS DURING THE AFTERNOON...AND WILL ALSO
BECOME FOCUSED ALONG A FRONT WHICH DROPS SOUTH OF THE PALMER DIVIDE
BETWEEN 21Z AND 00Z. CONVECTIVE BULLS-EYES ACROSS THE SOUTHEAST
PLAINS MEANDER FROM RUN TO RUN...BUT PARAMETERS ARE NOT FAVORABLE TO
PIN PRECIPITATION TO THE SOUTHEAST MOUNTAINS LONG ENOUGH TO CAUSE
PROBLEMS. STORM MOTIONS WILL BE TO THE EAST AT A PRETTY GOOD CLIP.
WILL KEEP MAINLY ISOLATED POPS FOR THE PLAINS DURING THE
AFTERNOON...WITH POPS INCREASING INTO THE EVENING HOURS AS THE FRONT
MOVES THROUGH.
TEMPERATURES TONIGHT WILL BE MILD WITH INCREASING CLOUD COVER.
HIGHS ON TUESDAY WILL BE COOLER OUT EAST WITH MORE WIDESPREAD
PRECIPITATION. MEANWHILE...WESTERLY DOWNSLOPE WINDS WILL BATTLE
CLOUD COVER AT TIMES ACROSS THE SOUTHEAST PLAINS...BUT OVERALL KEPT
MAX TEMPERATURES ON THE WARM SIDE. -KT
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 340 PM MDT MON SEP 8 2014
.TUESDAY NIGHT AND WEDNESDAY...SHOWERS AND THUNDERSTORMS WILL
LINGER INTO THE EVENING AS THE TROUGH PASSES THOUGH FROM THE
NORTHWEST. ANY CAPE SHOULD END BY LATER IN THE EVENING AS THE
COOLER MORE STABLE AIR MOVES INTO THE REGION. OVER THE
MOUNTAINS...LOWER LEVEL COLD AIR WILL BE TOO SHALLOW TO PASS OVER
THE EASTERN MOUNTAINS. KEPT SCATTER POPS OVER THE MOUNTAINS
OVERNIGHT AND INTO WEDNESDAY MORNING AS TROUGH WILL NOT PASS
THROUGH THE REGION UNTIL EARLY WEDNESDAY. ON WEDNESDAY...DRIER
AIR MASS ALOFT MOVES INTO THE REGION. ON THE PLAINS...ANOTHER
SURGE OF COOLER AIR MOVES INTO THE REGION BEHIND THE TROUGH.
ATMOSPHERE WILL BE TOO STABLE OVER THE PLAINS DURING THE DAY.
BUKFIT SOUNDINGS SUGGEST THERE MAY BE ENOUGH HEATING FOR SOME
LATER AFTERNOON THUNDERSTORMS ALONG THE INTERSTATE 25 CORRIDOR AND
OVER THE EASTERN MOUNTAINS. BY THE EVENING...THE COOL AIR ON THE
PLAINS MAY BECOME DEEP ENOUGH TO PRODUCE SOME VERY LIGHT SHOWERS
AND KEPT ISOLATED POPS IN THE GRIDS.
.THURSDAY AND FRIDAY...MODELS AND ENSEMBLES AGREE ON HAVING A
SHARPER TROUGH PASSING OVER THE REGION LATE THURSDAY INTO FRIDAY.
EC IS SLOWER...DEEPER AND COLDER WITH THE TROUGH. EC HAS 700MB
APPROACHING -4C OVER EL PASO COUNTY FRIDAY MORNING WHILE GFS IS
CLOSER TO +2C. ANTICIPATE A REASONABLE CHANCE OF LIGHT RAIN
THURSDAY EVENING AS THE TROUGH APPROACHES WITH THE COLD FRONTAL
PASSAGE. EC SOLUTION SUGGEST A BETTER CHANCE FOR PRECIPITATION THURSDAY
NIGHT. BEST CHANCES APPEAR TO BE FROM THE EASTERN MOUNTAINS AND
EASTWARD ASSOCIATED WITH THE MORE MOISTURE UPSLOPE FLOW. FRIDAY
HAS THE POTENTIAL TO BE A CHILLY AND CLOUDY DAY ON THE PLAINS AND
EASTERN MOUNTAINS. EXTENDED PROCEDURE GAVE HIGHS IN THE 50S OVER
THE PLAINS FRIDAY...WITH LOW CLOUDS LINGERING UNTIL AT LEAST MID
AFTERNOON. DEPENDING ON THE SPEED OF THE SYSTEM AND THE AMOUNT OF
CLOUDINESS...HIGH TEMPERATURES COULD EVEN BE COOLER. LOW LEVEL
COLD AIR MASS WILL MOSTLY STAY EAST ALONG AND EAST OF THE
EASTERN MOUNTAINS. WITH WARMING AND DRYING ALOFT...IT COULD BE A
SUNNY AND MILD DAY OVER THE REMAINING MOUNTAINS AND HIGH VALLEYS.
.SATURDAY THROUGH MONDAY...WILL HAVE TO WATCH FOR THE POTENTIAL
OF SOME FROST SATURDAY MORNING...DEPENDING ON THE AMOUNT OF
CLEARING. AFTERWARDS...A WARMING TREND WILL DEVELOP FOR THE
WEEKEND ESPECIALLY OVER THE PLAINS AND EASTERN MOUNTAINS AS THE
SURFACE HIGH MOVES EAST OF THE REGION. SOME MONSOON MOISTURE COULD
MOVE INTO THE MOUNTAINS OVER THE WEEKEND...AND INCREASED POPS
SLIGHTLY. OVER THE PLAINS...LOW LEVEL MOISTURE WILL RETURN ON
SUNDAY AND MONDAY...AND THE INCREASED MOISTURE COULD RESULT IN A
FEW AFTERNOON AND EVENING STORMS. --PGW--
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1117 PM MDT MON SEP 8 2014
SHOWERS INCREASING IN COVERAGE WEST OF THE CONTINENTAL DIVIDE AS
OF 05Z...AND EXPECT THIS TREND TO CONTINUE THROUGH THE NIGHT WITH
MOST MOUNTAINS OBSCURED BY 12Z. FOR TAF SITES...EXPECT VFR
CONDITIONS TO CONTINUE OVERNIGHT AND THROUGH THE DAY TUESDAY. AT
KALS...WILL CARRY A VCSH MENTION INTO THE MORNING TO ACCOUNT FOR
WEAK CONVECTION MOVING OFF THE SAN JUANS...THEN A VCTS MENTION FOR
LATE AFTERNOON AS MAIN UPPER TROUGH MOVES THROUGH. AT
KCOS...EXPECT MOST -SHRA TO REMAIN NORTH OF THE TERMINAL OVERNIGHT
INTO TUESDAY MORNING...THOUGH SOME LIGHT PRECIP WILL BE CLOSE BY
ALONG THE PALMER DIVIDE. COLD FRONT DROPS THROUGH THE AREA AFTER
20Z...WITH WINDOW FOR TSRA FROM ABOUT 20Z-02Z. SIMILAR FORECAST
FOR KPUB...WITH FRONT MOVING THROUGH DURING THE LATE AFTERNOON
WITH A CHANCE OF TSRA INTO EARLY EVENING.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH TUESDAY AFTERNOON FOR COZ067-068.
&&
$$
SHORT TERM...KT
LONG TERM...PGW
AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
339 PM EDT TUE SEP 9 2014
.SYNOPSIS...
AN ONSHORE FLOW PRODUCED BY THE COMBINED EFFECTS OF HIGH PRESSURE
EAST OF THE CANADIAN MARITIMES AND LOW PRESSURE OFF THE MID ATLANTIC
COAST WILL GRADUALLY WEAKEN ON WEDNESDAY AS BOTH SYSTEMS MOVE
FURTHER OFFSHORE. A COLD FRONT WILL MOVE THROUGH THE AREA THURSDAY
NIGHT, THEN STALL TO OUR SOUTH WHILE HIGH PRESSURE BUILDS IN FROM
THE NORTH ON FRIDAY. THE STALLED BOUNDARY COULD WORK ITS WAY BACK
NORTH SATURDAY, THEN OFFSHORE LATE IN THE WEEKEND. HIGH PRESSURE IS
THEN EXPECTED TO BUILD INTO THE MID-ATLANTIC REGION BY MONDAY.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
A LOW PRESSURE SYSTEM WILL CONTINUE TO MOVE NORTHEAST OFFSHORE
TONIGHT. EXPECT A RATHER CLOUDY NIGHT ACROSS THE REGION OVERALL
WHICH MAY KEEP LOW TEMPERATURES IN THE 60`S FOR MOST OF THE REGION.
COOLER TEMPERATURES WILL BE OBSERVED NW OF PHL. STAYED CLOSE TO
MAV/MET GUIDANCE WITH TEMPS AND DEWPOINTS. SOME ISOLATED SHOWERS ARE
PRESENT ACROSS THE EASTERN PORTIONS OF THE REGION AND WILL MOVE FROM
EAST TO WEST THROUGH THE REMAINDER OF THE AFTERNOON. SLIGHT CHANCE
POPS IN PLACE, BASICALLY FROM PHL TO THE SE. THE RAP SHOWS THE
POTENTIAL FOR SOME ADDTIONAL SCATTERED SHOWERS TO MOVE CLOSE TO THE
COAST TONIGHT AND A SLIGHT TO LOW CHANCE POP HAS BEEN LEFT IN THE
FORECAST TO ACCOUNT FOR THIS. LIGHT QPF UNDER 1/10TH INCH IS
EXPECTED, WITH RFC FORECAST QPF GUIDANCE USED OVERNIGHT AND THE
EARLY EVENING QPF FORECAST BASED MORE ON THE SREF. CONTINUED
NORTHEAST WINDS TONIGHT PERHAPS A FEW GUSTS EARLY AROUND 20 MPH.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
THE LOW PRESSURE SYSTEM WILL CONTINUE MOVING OFFSHORE ON
WEDNESDAY. THIS WILL ALLOW CLOUDS TO GRADUALLY CLEAR BY THE END OF
THE DAY AND ANY REMAINING POPS ARE BEFORE NOON ALONG THE SHORE. WINDS
WILL SHIFT AROUND TO THE SOUTHEAST AHEAD OF THE NEXT SYSTEM,
GENERALLY UNDER 10 MPH. WITH THE CLOUDCOVER HIGH TEMPERATURES MAY BE
HELD DOWN A BIT, SO DID NOT GO THE WARMER MET GUIDANCE. FORECASTED
TEMPERATURES TREND MORE TOWARD THE COOLER MAV GUIDANCE, RIGHT AROUND
80 FOR PHL AND 70`S FOR MOST.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
AS THE COASTAL LOW CONTINUES TO MOVE FURTHER OFFSHORE...WEAK HIGH
PRESSURE WILL BUILD IN WEDNESDAY NIGHT AND THURSDAY AS A COLD FRONT
APPROACHES FROM THE WEST. THE LATEST GFS RUN INDICATES THIS NEXT
COLD FRONT MIGHT ENTER OUR FAR WESTERN ZONES LATE THURSDAY
AFTERNOON...PASSING THROUGH THE REST OF THE CWA DURING THE EVENING
HOURS BEFORE REACHING THE COAST AROUND MIDNIGHT. THIS LATEST RUN
ALSO INDICATES THE FRONT MIGHT STALL A LITTLE FURTHER SOUTH OF OUR
AREA COMPARED TO EARLIER RUNS WHICH COULD TRANSLATE INTO A MOSTLY
PRECIPITATION-FREE WEEKEND AS HIGH PRESSURE MOVING THROUGH THE GREAT
LAKES BUILDS OVER THE REGION. THE ECMWF IS NOT AS OPTIMISTIC AND
KEEPS THE FRONT CLOSER TO OUR AREA, ALONG WITH A PROLONGED THREAT OF
SHOWER ACTIVITY FOR THE WEEKEND. IN TERMS OF THE FORECAST
GRIDS...AFTERNOON POPS ON THURSDAY ARE HIGHEST IN THE PA ZONES,
WHERE TIMING OF FROPA WOULD COINCIDE MORE FAVORABLY WITH PEAK
HEATING HOURS. THERE IS SOME DEGREE OF A THREAT FOR HEAVY RAINFALL
IN THUNDERSTORMS, BUT THE THREAT OF MAY BE MORE LOCALIZED THAN
WIDESPREAD. THEN POPS BECOME PROGRESSIVELY HIGHER FROM WEST TO EAST
AS THE FRONT MOVES THROUGH. A BASICALLY RAIN FREE PERIOD IS EXPECTED
LATER FRIDAY INTO EARLY SATURDAY, BUT SHOWERS COULD RETURN ONCE
AGAIN SATURDAY AFTERNOON INTO SUNDAY DEPENDING ON WHERE THE STALLED
FRONT ACTUALLY SETS UP SHOP. POPS THAT WERE ALREADY INTRODUCED INTO
THE GRIDS WERE BASICALLY KEPT IN THIS FCST CYCLE UNTIL MODEL
INFORMATION BECOMES MORE CERTAIN. IMPROVEMENTS ARE EXPECTED EARLY
NEXT WEEK AS HIGH PRESSURE MOVES IN FROM THE NORTHWEST.
IN TERMS OF TEMPERATURES...ABOVE NORMAL EXPECTED UNTIL THE FRONT
MOVES THROUGH THURSDAY NIGHT...THEN NEAR TO SLIGHTLY BELOW NORMAL
AFTER THAT.
&&
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
OUR REGION HAS BEEN GRAZED BY SOME CLOUDS FROM A LOW PRESSURE
SYSTEM TODAY TO OUR SOUTHEAST. CEILINGS HAVE BEEN VFR FOR THE MOST
PART WITH SOME LOCAL MVFR RESTRICTIONS. TEMPO GROUPS ARE INCLUDED
IN THE 18Z TAFS FOR PLACES THAT HAVE SEEN BRIEF RESTRICTIONS TO
MVFR. NORTHEAST WINDS WILL ALSO CONTINUE TO BE IN PLACE FROM 10-15
KNOTS TODAY, HIGHER GUSTS AROUND 20 KNOTS WILL CONTINUE TO BE
SCATTERED THROUGHOUT THE REGION THIS AFTERNOON.
OVERNIGHT CEILINGS ARE LIKELY TO LOWER TO MVFR AROUND MIDNIGHT.
SOME DATA HINTS AT CEILINGS LOWERING TO NEAR IFR LEVELS TOWARD SUNRISE.
HOWEVER, CONFIDENCE FOR IFR IS LOW, LEFT OUT OF TAFS ATTM.
CLOUDS SHOULD RAISE AND BREAK UP WEDNESDAY WITH A NORTHEAST WIND
SHIFTING TO THE SOUTH BY WEDNESDAY NIGHT.
OUTLOOK...
WEDNESDAY NIGHT...VFR IN THE EVE. LOW CLOUDS AND FOG MAY DEVELOP
OVERNIGHT.
THURSDAY AND THURSDAY NIGHT...SHRA AND TSRA LIKELY IN THE AFTN AT
RDG/ABE. THIS ACTIVITY MAY HOLD OFF FARTHER EAST UNTIL THE EVE
WHEN A COLD FRONT MOVES THRU. FROPA WILL BE MARKED BY WIND SHIFT
FROM S TO NW.
FRIDAY AND FRIDAY NIGHT...VFR
SATURDAY AND SUNDAY...CHANCE OF SHRA WITH SUB-VFR CONDITIONS POSSIBLE.
&&
.MARINE...
SEAS ARE CURRENTLY RUNNING WELL OVER FIVE FEET ON THE OCEAN WATERS.
WITH THE CONTINUED ONSHORE FLOW SEAS WILL LIKELY BE OVER FIVE FEET
THROUGH WEDNESDAY. AS A RESULT, THE SMALL CRAFT ADVISORY HAS BEEN
EXTENDED THROUGH WEDNESDAY NIGHT ON THE OCEAN WATERS. WINDS AROUND 20
KNOTS ARE LIKELY WITH THE POTENTIAL FOR SCA CRITERIA GUSTS THROUGH
TONIGHT AND INTO WEDNESDAY MORNING ON THE OCEAN WATERS. FOR DELAWARE
BAY, WINDS HAVE GENERALLY BEEN AT OR UNDER 20 KNOTS AND WITH LOWER
SEAS ONGOING. WE`LL ALLOW THE SCA TO EXPIRE AT 6PM ON THE BAY.
OUTLOOK...
WEDNESDAY NIGHT...THE PRESSURE GRADIENT GRADUALLY WEAKENS AND
WINDS SHOULD DECREASE TO BELOW SCA LEVELS BY THE AFTN. HOWEVER,
THE SCA MAY STILL BE NEEDED AS SEAS WILL TAKE TIME TO SUBSIDE. THE
LATEST GUIDANCE SUGGESTS WAVES OF 4-5 FT FOR THIS PERIOD.
THURSDAY...SOUTHERLY WINDS INCREASE AHEAD OF A FRONT BUT SHOULD
REMAIN BELOW SCA LVLS.
THURSDAY NIGHT AND FRIDAY MORNING...COLD FRONT MOVES THRU THE WATERS
THURSDAY NIGHT. STORMS MAY PRODUCE LOCALLY GUSTY WINDS JUST AHEAD OF
THE FRONT DURING THE EVE. PRESSURE SURGE IN WAKE OF FROPA MAY
PRODUCE A BRIEF PERIOD OF NW WINDS GUSTING TO NEAR SCA THRESHOLD
LATE THURSDAY NIGHT INTO FRIDAY MORNING.
FRIDAY AFTERNOON THROUGH SUNDAY....NO MARINE HEADLINES ARE
EXPECTED.
&&
.TIDES/COASTAL FLOODING...
WITH A COASTAL LOW MEANDERING JUST OFFSHORE AND ONSHORE FLOW
CONTINUING, THE THREAT OF MINOR COASTAL FLOODING IS EXPECTED TO
CONTINUE INTO AT LEAST WEDNESDAY MORNING`S HIGH TIDE CYCLE.
MARGINAL MINOR TIDAL FLOODING OCCURRED ALONG THE COASTS OF NEW
JERSEY AND DELAWARE AND INTO DELAWARE BAY WITH THE TUESDAY MORNING
HIGH TIDE CYCLE. THE LATEST MODEL GUIDANCE INDICATES THAT SIMILAR OR
SLIGHTLY HIGHER LEVELS ARE EXPECTED WITH THIS EVENING`S HIGH TIDE AS
THE ONSHORE FLOW PERSISTS. GOING INTO WEDNESDAY MORNING AND MIDDAY,
THE PRESSURE GRADIENT ALONG THE COAST LOOKS TO TIGHTEN SOMEWHAT, AND
THE WINDS ARE FORECAST TO BECOME A LITTLE MORE NORTHEASTERLY. WE
THEREFORE HAVE EXTENDED THE CURRENT COASTAL FLOOD ADVISORY THROUGH
THE WEDNESDAY MORNING TO MIDDAY HIGH TIDE CYCLE.
&&
.RIP CURRENTS...
A HIGH RISK OF DANGEROUS RIP CURRENTS TODAY AND THIS EVE WITH
BREEZY NE FLOW AND A NEAR FULL MOON.
THE THREAT FOR RIP CURRENTS ON WEDNESDAY IS EXPECTED TO BE AT
LEAST MODERATE.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...COASTAL FLOOD ADVISORY UNTIL 2 PM EDT WEDNESDAY FOR NJZ012>014-
020-022>027.
COASTAL FLOOD ADVISORY UNTIL 4 PM EDT WEDNESDAY FOR NJZ016-021.
DE...COASTAL FLOOD ADVISORY UNTIL 2 PM EDT WEDNESDAY FOR DEZ003-004.
COASTAL FLOOD ADVISORY UNTIL 4 PM EDT WEDNESDAY FOR DEZ001-002.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT WEDNESDAY NIGHT FOR
ANZ450>455.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ430-
431.
&&
$$
SYNOPSIS...MIKETTA
NEAR TERM...GAINES/NIERENBERG
SHORT TERM...GAINES/NIERENBERG
LONG TERM...MIKETTA
AVIATION...GAINES/NIERENBERG/MIKETTA
MARINE...GAINES/NIERENBERG/MIKETTA
TIDES/COASTAL FLOODING...
RIP CURRENTS...O`HARA
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
118 PM EDT TUE SEP 9 2014
.SYNOPSIS...
AN AREA OF LOW PRESSURE DEVELOPING ALONG THE NORTH CAROLINA COAST
TODAY WILL DRIFT NORTHEASTWARD OFF THE MID-ATLANTIC COAST THROUGH
WEDNESDAY. A COLD FRONT WILL APPROACH FROM THE WEST THURSDAY BEFORE
MOVING THROUGH THE AREA THURSDAY NIGHT. THE FRONT WILL STALL TO OUR
SOUTH WHILE HIGH PRESSURE BUILDS IN FROM THE NORTHERN PLAINS FRIDAY.
THE STALLED BOUNDARY WILL RETURN NORTHWARD TOWARD THE REGION
SATURDAY BEFORE THE FRONT GRADUALLY MOVES OFFSHORE LATE IN THE
WEEKEND. HIGH PRESSURE IS EXPECTED TO BUILD BACK INTO THE MID-
ATLANTIC STATES BY MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LOW PRESSURE OFF THE MID-ATLANTIC COAST WILL MOVE UP INTO THE
WATERS OFF TIDEWATER VA LATER TODAY. IT APPEARS FROM THE LATEST
MODELS THAT ONLY SRN- MOST NJ AND THE DELMARVA WILL BE THE ONLY
AREAS THAT WILL GET ANY PCPN FROM THIS SYSTEM. POPS HAVE BEEN
SCALED BACK ONLY INDICATING A SLIGHT TO LOW CHANCE POP FROM PHL
EAST WITH THE 12:30 PM UPDATE. THE HRRR WAS OVERDONE WITH REALITY
THIS MORNING ON THE POPS WITH THE RAP HAVING A BETTER HANDLE ON
SHORT TERM CONDITIONS. CLOUDS AND A MOIST E/NE FLOW WILL BE ACROSS
MOST OF THE REST OF THE AREA. WE HAVE FOLLOWED THE GFS MODEL WITH
THIS FCST...ALTHOUGH THE NAM AND 12Z EC ARE ALL REASONABLY CLOSE
WITH REGARDS TO THE TRACK AND EFFECTS WITH THE LOW. HIGHS
TODAY...MOSTLY LOW/MID 70S WITH A FEW UPPER 60S OVER THE SRN
POCONOS. MINOR ADJUSTMENTS TO THE TEMPERATURES WERE MADE WITH BOTH
THE MORNING AND AFTERNOON UPDATE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
THE LOW WILL CONTINUE TO MOVE NE AND IT WILL BE WELL E OF DEL BY 12Z
WED. CLOUDS WILL REMAIN ACROSS MOST OF THE AREA TONIGHT...WITH
SHOWERS OR LIGHT RAIN ACROSS MOSTLY THE SRN COASTAL AREAS. E/NE
WINDS WILL CONTINUE ACROSS THE AREA WITH A COOL/DAMPNESS EXPECTED
ALONG THE COAST. TEMPS TONIGHT...LOW/MID 50S ACROSS THE NORTH WITH
SOME BREAKS POSSIBLE RANGING TO THE LOW/MID 60S ELSEWHERE.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
00Z MODEL GUIDANCE IS IN FAIRLY GOOD AGREEMENT WITH TIMING OF H5
SHORTWAVE TROUGH ON WEDNESDAY. LIFT AHEAD OF THIS MID-LVL TROUGH AND
IN LEFT-EXIT REGION OF UPPER-LVL JET STREAK WILL BE PROGRESSING
DOWNSTREAM OF THE AREA DURING THE MORNING. THE COASTAL LOW IS
FORECAST TO MEANDER OFF THE DELMARVA COAST DURING THIS TIME.
ENHANCED WRAP-AROUND MOISTURE FROM THE ATLANTIC OCEAN WOULD MOST
LIKELY REMAIN OFFSHORE GIVEN THE POSITION OF THE COASTAL LOW. RAIN
MAY LINGER NEAR THE DE AND SOUTHERN NJ COAST DURING THE MORNING. A
DRYING TREND IS EXPECTED FOR THE AFTERNOON WITH THE COASTAL LOW
DRIFTING FARTHER OFF THE MID-ATLANTIC COAST WHILE THE UPPER DYNAMICS
ASSOCIATED WITH THE SHORTWAVE TROUGH SHIFTS FARTHER OFFSHORE.
FAVORED THE COOLER MAV GUIDANCE FOR MAX TEMPS WEDNESDAY AS MARINE
STRATOCU MAY BE STUBBORN TO ERODE UNDER THE PERSISTENCE OF ONSHORE
FLOW IN THE BOUNDARY LAYER.
A WEAK RIDGE OF HIGH PRESSURE IS EXPECTED TO BUILD OVER THE EASTERN
SEABOARD WEDNESDAY NIGHT WHILE THE COASTAL LOW CONTINUES TO DRIFT
FARTHER OFF THE NORTHERN MID-ATLANTIC COAST. WILL NEED TO MONITOR
FOR THE POTENTIAL OF STRATUS AND/OR FOG DEVELOPMENT (PARTICULARLY AT
LOCATIONS CLOSER TO THE COAST) WITH RESIDUAL MARINE AIR OVERHEAD.
FARTHER WEST INTO PA, LOW-LEVEL WINDS DO BEGIN TO VEER OUT OF THE
SOUTH OVERNIGHT AHEAD OF A COLD FRONT THAT IS APPROACHING FROM THE
WEST.
AFOREMENTIONED COLD FRONT IS EXPECTED TO MOVE INTO THE MID-ATLANTIC
AND NORTHEAST STATES ON THURSDAY. THE 00Z GFS WAS ABOUT 6 HOURS
FASTER WITH THE FROPA THAN THE 00Z NAM/ECMWF/CMC AND GEFS MEAN. A
SLOWER SOLUTION WOULD BE FAVORED IN THIS SETUP WITH THE DEEPENING
CYCLONE EXPECTED TO CUT WELL TO OUR NORTHWEST ACROSS QUEBEC.
AFTERNOON POPS HIGHEST IN THE PA ZONES, WHERE TIMING OF FROPA WOULD
COINCIDE MORE FAVORABLY WITH PEAK HEATING HOURS. INTERESTINGLY, BOTH
THE 00Z NAM/GFS OPERATIONAL RUNS SHOW AN IMPRESSIVE WARM CONVEYOR
BELT WITH PWATS WITHIN THE WELL-DEFINED ATMOSPHERIC RIVER NEAR +3SD
OVER THE MID-ATLANTIC COAST THURSDAY EVENING. THERE IS SOME DEGREE
OF A THREAT FOR HEAVY RAINFALL IN THUNDERSTORMS, BUT THE THREAT OF
MAY BE MORE LOCALIZED ACROSS OUR AREA DUE TO A LACK OF SYNOPTIC LIFT
NOTED IN THE MID AND UPPER LEVELS.
A BROAD AREA OF HIGH PRESSURE OVER THE NORTHERN PLAINS BUILDS
EASTWARD INTO THE AREA ON FRIDAY. THE COLD FRONT THAT MOVES THROUGH
THE REGION THURSDAY NIGHT WILL STALL TO OUR SOUTH ON FRIDAY. DRY
CONDITIONS AND SLIGHTLY BELOW NORMAL TEMPS ARE EXPECTED TO CLOSE
OUT THE WORK WEEK.
A NORTHERN-STREAM SHORTWAVE TROUGH IS FORECAST TO TRACK THRU THE
GREAT LAKES ON SATURDAY. SOUTHERLY FLOW STRENGTHENING AHEAD OF THIS
SYSTEM WOULD ALLOW THE STALLED FRONTAL BOUNDARY TO OUR SOUTH TO LIFT
NORTHWARD TOWARD OUR AREA. THERE IS A POTENTIAL FOR THE WEEKEND TO
START OUT WET UNDER THIS SETUP AS WARM AND MOIST AIR OVERRUNS THE
BOUNDARY. MODELS ARE HINTING AT THE POTENTIAL FOR A SECONDARY WAVE
OF LOPRES TO DEVELOP NEAR THE MID-ATLANTIC COAST. IF LOPRES DEVELOPS
CLOSE ENOUGH TO THE COAST, THE FRONT WOULD BE SLOWER TO PUSH
OFFSHORE AND PRECIP COULD LINGER INTO SUNDAY (ESPECIALLY AT COASTAL
LOCATIONS). POPS WERE KEPT AT 20-30 PERCENT WITH HIGH FORECAST
UNCERTAINTY. TEMPS WILL BE SLIGHTLY BELOW NORMAL THIS WEEKEND OWING
TO THE CLOUD COVER AND ONSHORE FLOW.
HIGH PRESSURE BUILDS BACK IN FROM THE WEST BY EARLY NEXT WEEK.
&&
.AVIATION /17Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
OUR REGION HAS BEEN GRAZED BY SOME CLOUDS FROM A LOW PRESSURE
SYSTEM TODAY TO OUR SOUTHEAST. CEILINGS HAVE BEEN VFR FOR THE MOST
PART WITH SOME LOCAL MVFR RESTRICTIONS. TEMPO GROUPS ARE INCLUDED
IN THE 18Z TAFS FOR PLACES THAT HAVE SEEN BRIEF RESTRICTIONS TO
MVFR. NORTHEAST WINDS WILL ALSO CONTINUE TO BE IN PLACE FROM 10-15
KNOTS TODAY, HIGHER GUSTS AROUND 20 KNOTS WILL CONTINUE TO BE
SCATTERED THROUGHOUT THE REGION THIS AFTERNOON.
OVERNIGHT CEILINGS ARE LIKELY TO LOWER TO MVFR AROUND MIDNIGHT.
SOME DATA HINTS AT CEILINGS LOWERING TO NEAR IFR LEVELS TOWARD SUNRISE.
HOWEVER, CONFIDENCE FOR IFR IS LOW, LEFT OUT OF TAFS ATTM.
CLOUDS SHOULD RAISE AND BREAK UP WEDNESDAY WITH A NORTHEAST WIND
SHIFTING TO THE SOUTH BY WEDNESDAY NIGHT.
OUTLOOK...
WEDNESDAY NIGHT...VFR IN THE EVE. LOW CLOUDS AND FOG MAY DEVELOP
OVERNIGHT.
THURSDAY AND THURSDAY NIGHT...SHRA AND TSRA LIKELY IN THE AFTN AT
RDG/ABE. THIS ACTIVITY MAY HOLD OFF FARTHER EAST UNTIL THIS EVE
AND OVNGT WHEN A COLD FRONT MOVES THRU. FROPA WILL BE MARKED BY
WIND SHIFT FROM S TO NW.
FRIDAY AND FRIDAY NIGHT...VFR
SATURDAY...CHANCE OF SHRA WITH SUB-VFR CONDITIONS POSSIBLE.
&&
.MARINE...
WE WILL KEEP THE SCA FLAG ACROSS THE WATERS TODAY AND TONIGHT. GUSTS
IN THE 25 TO 30 KNOT RANGE EXPECTED ON THE OCEAN AND MORE IN THE 20
TO 25 KNOT RANGE FOR DEL BAY. SCA IS KINDA MARGINAL THERE. DECENT
SEAS 6 TO 8 FT ON THE OCEAN...AND A FEW HIGHER SEAS ACROSS THE MOUTH
OF DEL BAY. SHOWERS MOSTLY SOUTH/EAST TODAY AND EARLY TONIGHT.
OUTLOOK...
WEDNESDAY MORNING...SCA EXTENDED INTO WED MRNG WITH NE WINDS AROUND
A COASTAL LOW GUSTING TO 25 KT. SEAS BETWEEN 5-7 FT ARE EXPECTED.
WEDNESDAY AFTERNOON AND WEDNESDAY NIGHT...THE PRESSURE GRADIENT
GRADUALLY WEAKENS AND WINDS SHOULD DECREASE TO BELOW SCA LEVELS BY
THE AFTN. HOWEVER, THE SCA MAY NEED TO BE EXTENDED DURING THIS TIME
AS SEAS WILL TAKE TIME TO SUBSIDE. THE LATEST GUIDANCE SUGGESTS
WAVES OF 4-5 FT FOR THIS PERIOD.
THURSDAY...SOUTHERLY WINDS INCREASE AHEAD OF A FRONT BUT SHOULD
REMAIN BELOW SCA LVLS.
THURSDAY NIGHT AND FRIDAY MORNING...COLD FRONT MOVES THRU THE WATERS
THURSDAY NIGHT. STORMS MAY PRODUCE LOCALLY GUSTY WINDS JUST AHEAD OF
THE FRONT DURING THE EVE. PRESSURE SURGE IN WAKE OF FROPA MAY
PRODUCE A BRIEF PERIOD OF NW WINDS GUSTING TO NEAR SCA THRESHOLD
LATE THURSDAY NIGHT INTO FRIDAY MORNING.
FRIDAY AFTERNOON THROUGH SATURDAY....NO MARINE HEADLINES ARE
EXPECTED.
&&
.TIDES/COASTAL FLOODING...
WITH A COASTAL LOW MEANDERING JUST OFFSHORE AND ONSHORE FLOW
CONTINUING, THE THREAT OF MINOR COASTAL FLOODING IS EXPECTED TO
CONTINUE INTO AT LEAST WEDNESDAY MORNING`S HIGH TIDE CYCLE.
MARGINAL MINOR TIDAL FLOODING OCCURRED ALONG THE COASTS OF NEW
JERSEY AND DELAWARE AND INTO DELAWARE BAY WITH THE TUESDAY MORNING
HIGH TIDE CYCLE. THE LATEST MODEL GUIDANCE INDICATES THAT SIMILAR OR
SLIGHTLY HIGHER LEVELS ARE EXPECTED WITH THIS EVENING`S HIGH TIDE AS
THE ONSHORE FLOW PERSISTS. GOING INTO WEDNESDAY MORNING AND MIDDAY,
THE PRESSURE GRADIENT ALONG THE COAST LOOKS TO TIGHTEN SOMEWHAT, AND
THE WINDS ARE FORECAST TO BECOME A LITTLE MORE NORTHEASTERLY. WE
THEREFORE HAVE EXTENDED THE CURRENT COASTAL FLOOD ADVISORY THROUGH
THE WEDNESDAY MORNING TO MIDDAY HIGH TIDE CYCLE.
&&
.RIP CURRENTS...
A HIGH RISK OF DANGEROUS RIP CURRENTS TODAY AND THIS EVE WITH
BREEZY NE FLOW AND A NEAR FULL MOON.
THE THREAT FOR RIP CURRENTS ON WEDNESDAY IS EXPECTED TO BE AT
LEAST MODERATE.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...COASTAL FLOOD ADVISORY UNTIL 2 PM EDT WEDNESDAY FOR NJZ012>014-
020-022>027.
COASTAL FLOOD ADVISORY UNTIL 4 PM EDT WEDNESDAY FOR NJZ016-021.
DE...COASTAL FLOOD ADVISORY UNTIL 2 PM EDT WEDNESDAY FOR DEZ003-004.
COASTAL FLOOD ADVISORY UNTIL 4 PM EDT WEDNESDAY FOR DEZ001-002.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL NOON EDT WEDNESDAY FOR ANZ450>455.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ430-
431.
&&
$$
SYNOPSIS...KLEIN
NEAR TERM...GAINES/O`HARA
SHORT TERM...O`HARA
LONG TERM...KLEIN
AVIATION...GAINES/KLEIN
MARINE...KLEIN/O`HARA
TIDES/COASTAL FLOODING...
RIP CURRENTS...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1255 PM EDT TUE SEP 9 2014
.SYNOPSIS...
AN AREA OF LOW PRESSURE DEVELOPING ALONG THE NORTH CAROLINA COAST
TODAY WILL DRIFT NORTHEASTWARD OFF THE MID-ATLANTIC COAST THROUGH
WEDNESDAY. A COLD FRONT WILL APPROACH FROM THE WEST THURSDAY BEFORE
MOVING THROUGH THE AREA THURSDAY NIGHT. THE FRONT WILL STALL TO OUR
SOUTH WHILE HIGH PRESSURE BUILDS IN FROM THE NORTHERN PLAINS FRIDAY.
THE STALLED BOUNDARY WILL RETURN NORTHWARD TOWARD THE REGION
SATURDAY BEFORE THE FRONT GRADUALLY MOVES OFFSHORE LATE IN THE
WEEKEND. HIGH PRESSURE IS EXPECTED TO BUILD BACK INTO THE MID-
ATLANTIC STATES BY MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LOW PRESSURE OFF THE MID-ATLANTIC COAST WILL MOVE UP INTO THE
WATERS OFF TIDEWATER VA LATER TODAY. IT APPEARS FROM THE LATEST
MODELS THAT ONLY SRN- MOST NJ AND THE DELMARVA WILL BE THE ONLY
AREAS THAT WILL GET ANY PCPN FROM THIS SYSTEM. POPS HAVE BEEN
SCALED BACK ONLY INDICATING A SLIGHT TO LOW CHANCE POP FROM PHL
EAST WITH THE 12:30 PM UPDATE. THE HRRR WAS OVERDONE WITH REALITY
THIS MORNING ON THE POPS WITH THE RAP HAVING A BETTER HANDLE ON
SHORT TERM CONDITIONS. CLOUDS AND A MOIST E/NE FLOW WILL BE ACROSS
MOST OF THE REST OF THE AREA. WE HAVE FOLLOWED THE GFS MODEL WITH
THIS FCST...ALTHOUGH THE NAM AND 12Z EC ARE ALL REASONABLY CLOSE
WITH REGARDS TO THE TRACK AND EFFECTS WITH THE LOW. HIGHS
TODAY...MOSTLY LOW/MID 70S WITH A FEW UPPER 60S OVER THE SRN
POCONOS. MINOR ADJUSTMENTS TO THE TEMPERATURES WERE MADE WITH BOTH
THE MORNING AND AFTERNOON UPDATE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
THE LOW WILL CONTINUE TO MOVE NE AND IT WILL BE WELL E OF DEL BY 12Z
WED. CLOUDS WILL REMAIN ACROSS MOST OF THE AREA TONIGHT...WITH
SHOWERS OR LIGHT RAIN ACROSS MOSTLY THE SRN COASTAL AREAS. E/NE
WINDS WILL CONTINUE ACROSS THE AREA WITH A COOL/DAMPNESS EXPECTED
ALONG THE COAST. TEMPS TONIGHT...LOW/MID 50S ACROSS THE NORTH WITH
SOME BREAKS POSSIBLE RANGING TO THE LOW/MID 60S ELSEWHERE.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
00Z MODEL GUIDANCE IS IN FAIRLY GOOD AGREEMENT WITH TIMING OF H5
SHORTWAVE TROUGH ON WEDNESDAY. LIFT AHEAD OF THIS MID-LVL TROUGH AND
IN LEFT-EXIT REGION OF UPPER-LVL JET STREAK WILL BE PROGRESSING
DOWNSTREAM OF THE AREA DURING THE MORNING. THE COASTAL LOW IS
FORECAST TO MEANDER OFF THE DELMARVA COAST DURING THIS TIME.
ENHANCED WRAP-AROUND MOISTURE FROM THE ATLANTIC OCEAN WOULD MOST
LIKELY REMAIN OFFSHORE GIVEN THE POSITION OF THE COASTAL LOW. RAIN
MAY LINGER NEAR THE DE AND SOUTHERN NJ COAST DURING THE MORNING. A
DRYING TREND IS EXPECTED FOR THE AFTERNOON WITH THE COASTAL LOW
DRIFTING FARTHER OFF THE MID-ATLANTIC COAST WHILE THE UPPER DYNAMICS
ASSOCIATED WITH THE SHORTWAVE TROUGH SHIFTS FARTHER OFFSHORE.
FAVORED THE COOLER MAV GUIDANCE FOR MAX TEMPS WEDNESDAY AS MARINE
STRATOCU MAY BE STUBBORN TO ERODE UNDER THE PERSISTENCE OF ONSHORE
FLOW IN THE BOUNDARY LAYER.
A WEAK RIDGE OF HIGH PRESSURE IS EXPECTED TO BUILD OVER THE EASTERN
SEABOARD WEDNESDAY NIGHT WHILE THE COASTAL LOW CONTINUES TO DRIFT
FARTHER OFF THE NORTHERN MID-ATLANTIC COAST. WILL NEED TO MONITOR
FOR THE POTENTIAL OF STRATUS AND/OR FOG DEVELOPMENT (PARTICULARLY AT
LOCATIONS CLOSER TO THE COAST) WITH RESIDUAL MARINE AIR OVERHEAD.
FARTHER WEST INTO PA, LOW-LEVEL WINDS DO BEGIN TO VEER OUT OF THE
SOUTH OVERNIGHT AHEAD OF A COLD FRONT THAT IS APPROACHING FROM THE
WEST.
AFOREMENTIONED COLD FRONT IS EXPECTED TO MOVE INTO THE MID-ATLANTIC
AND NORTHEAST STATES ON THURSDAY. THE 00Z GFS WAS ABOUT 6 HOURS
FASTER WITH THE FROPA THAN THE 00Z NAM/ECMWF/CMC AND GEFS MEAN. A
SLOWER SOLUTION WOULD BE FAVORED IN THIS SETUP WITH THE DEEPENING
CYCLONE EXPECTED TO CUT WELL TO OUR NORTHWEST ACROSS QUEBEC.
AFTERNOON POPS HIGHEST IN THE PA ZONES, WHERE TIMING OF FROPA WOULD
COINCIDE MORE FAVORABLY WITH PEAK HEATING HOURS. INTERESTINGLY, BOTH
THE 00Z NAM/GFS OPERATIONAL RUNS SHOW AN IMPRESSIVE WARM CONVEYOR
BELT WITH PWATS WITHIN THE WELL-DEFINED ATMOSPHERIC RIVER NEAR +3SD
OVER THE MID-ATLANTIC COAST THURSDAY EVENING. THERE IS SOME DEGREE
OF A THREAT FOR HEAVY RAINFALL IN THUNDERSTORMS, BUT THE THREAT OF
MAY BE MORE LOCALIZED ACROSS OUR AREA DUE TO A LACK OF SYNOPTIC LIFT
NOTED IN THE MID AND UPPER LEVELS.
A BROAD AREA OF HIGH PRESSURE OVER THE NORTHERN PLAINS BUILDS
EASTWARD INTO THE AREA ON FRIDAY. THE COLD FRONT THAT MOVES THROUGH
THE REGION THURSDAY NIGHT WILL STALL TO OUR SOUTH ON FRIDAY. DRY
CONDITIONS AND SLIGHTLY BELOW NORMAL TEMPS ARE EXPECTED TO CLOSE
OUT THE WORK WEEK.
A NORTHERN-STREAM SHORTWAVE TROUGH IS FORECAST TO TRACK THRU THE
GREAT LAKES ON SATURDAY. SOUTHERLY FLOW STRENGTHENING AHEAD OF THIS
SYSTEM WOULD ALLOW THE STALLED FRONTAL BOUNDARY TO OUR SOUTH TO LIFT
NORTHWARD TOWARD OUR AREA. THERE IS A POTENTIAL FOR THE WEEKEND TO
START OUT WET UNDER THIS SETUP AS WARM AND MOIST AIR OVERRUNS THE
BOUNDARY. MODELS ARE HINTING AT THE POTENTIAL FOR A SECONDARY WAVE
OF LOPRES TO DEVELOP NEAR THE MID-ATLANTIC COAST. IF LOPRES DEVELOPS
CLOSE ENOUGH TO THE COAST, THE FRONT WOULD BE SLOWER TO PUSH
OFFSHORE AND PRECIP COULD LINGER INTO SUNDAY (ESPECIALLY AT COASTAL
LOCATIONS). POPS WERE KEPT AT 20-30 PERCENT WITH HIGH FORECAST
UNCERTAINTY. TEMPS WILL BE SLIGHTLY BELOW NORMAL THIS WEEKEND OWING
TO THE CLOUD COVER AND ONSHORE FLOW.
HIGH PRESSURE BUILDS BACK IN FROM THE WEST BY EARLY NEXT WEEK.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THE 06Z TAFS WERE SOMEWHAT MORE OPTIMISTIC WITH REGARDS TO
CIGS/VSBYS AT OUR TERMINALS. IT APPEARS THAT THE GFS/NAM ARE KEEPING
MUCH OF THE POORER CONDITIONS CLOSER TO THE LOW WHICH WILL PASS
SOUTH/EAST OF THE DEL VALLEY TAF SITES. KMIV/KACY WILL HAVE MORE OF
AN IMPACT...BUT STILL NOT AS LOW AS PREVIOUSLY FCST. WINDS WILL
INCREASE FROM THE E/ENE TODAY WITH SPEEDS 5 TO 10 KTS INLAND AND 10
TO 15 KTS ACROSS SRN NJ AND INTO DEL. IMPROVEMENT BACK TO VFR
EXPECTED IN MOST AREAS THIS AFTERNOON...THEN GUIDANCE SHOWING LOWER
CONDITIONS TONIGHT.
OUTLOOK...
WEDNESDAY...LOW CLOUDS AND MVFR CIGS MAY LINGER INTO WED MRNG,
ESPECIALLY NEAR THE COAST. CIGS IMPROVE TO VFR WED AFTN.
WEDNESDAY NIGHT...VFR IN THE EVE. LOW CLOUDS AND FOG MAY DEVELOP
OVERNIGHT.
THURSDAY AND THURSDAY NIGHT...SHRA AND TSRA LIKELY IN THE AFTN AT
RDG/ABE. THIS ACTIVITY MAY HOLD OFF FARTHER EAST UNTIL THIS EVE
AND OVNGT WHEN A COLD FRONT MOVES THRU. FROPA WILL BE MARKED BY
WIND SHIFT FROM S TO NW.
FRIDAY AND FRIDAY NIGHT...VFR
SATURDAY...CHANCE OF SHRA WITH SUB-VFR CONDITIONS POSSIBLE.
&&
.MARINE...
WE WILL KEEP THE SCA FLAG ACROSS THE WATERS TODAY AND TONIGHT. GUSTS
IN THE 25 TO 30 KNOT RANGE EXPECTED ON THE OCEAN AND MORE IN THE 20
TO 25 KNOT RANGE FOR DEL BAY. SCA IS KINDA MARGINAL THERE. DECENT
SEAS 6 TO 8 FT ON THE OCEAN...AND A FEW HIGHER SEAS ACROSS THE MOUTH
OF DEL BAY. SHOWERS MOSTLY SOUTH/EAST TODAY AND EARLY TONIGHT.
OUTLOOK...
WEDNESDAY MORNING...SCA EXTENDED INTO WED MRNG WITH NE WINDS AROUND
A COASTAL LOW GUSTING TO 25 KT. SEAS BETWEEN 5-7 FT ARE EXPECTED.
WEDNESDAY AFTERNOON AND WEDNESDAY NIGHT...THE PRESSURE GRADIENT
GRADUALLY WEAKENS AND WINDS SHOULD DECREASE TO BELOW SCA LEVELS BY
THE AFTN. HOWEVER, THE SCA MAY NEED TO BE EXTENDED DURING THIS TIME
AS SEAS WILL TAKE TIME TO SUBSIDE. THE LATEST GUIDANCE SUGGESTS
WAVES OF 4-5 FT FOR THIS PERIOD.
THURSDAY...SOUTHERLY WINDS INCREASE AHEAD OF A FRONT BUT SHOULD
REMAIN BELOW SCA LVLS.
THURSDAY NIGHT AND FRIDAY MORNING...COLD FRONT MOVES THRU THE WATERS
THURSDAY NIGHT. STORMS MAY PRODUCE LOCALLY GUSTY WINDS JUST AHEAD OF
THE FRONT DURING THE EVE. PRESSURE SURGE IN WAKE OF FROPA MAY
PRODUCE A BRIEF PERIOD OF NW WINDS GUSTING TO NEAR SCA THRESHOLD
LATE THURSDAY NIGHT INTO FRIDAY MORNING.
FRIDAY AFTERNOON THROUGH SATURDAY....NO MARINE HEADLINES ARE
EXPECTED.
&&
.TIDES/COASTAL FLOODING...
WITH A COASTAL LOW MEANDERING JUST OFFSHORE AND ONSHORE FLOW
CONTINUING, THE THREAT OF MINOR COASTAL FLOODING IS EXPECTED TO
CONTINUE INTO AT LEAST WEDNESDAY MORNING`S HIGH TIDE CYCLE.
MARGINAL MINOR TIDAL FLOODING OCCURRED ALONG THE COASTS OF NEW
JERSEY AND DELAWARE AND INTO DELAWARE BAY WITH THE TUESDAY MORNING
HIGH TIDE CYCLE. THE LATEST MODEL GUIDANCE INDICATES THAT SIMILAR OR
SLIGHTLY HIGHER LEVELS ARE EXPECTED WITH THIS EVENING`S HIGH TIDE AS
THE ONSHORE FLOW PERSISTS. GOING INTO WEDNESDAY MORNING AND MIDDAY,
THE PRESSURE GRADIENT ALONG THE COAST LOOKS TO TIGHTEN SOMEWHAT, AND
THE WINDS ARE FORECAST TO BECOME A LITTLE MORE NORTHEASTERLY. WE
THEREFORE HAVE EXTENDED THE CURRENT COASTAL FLOOD ADVISORY THROUGH
THE WEDNESDAY MORNING TO MIDDAY HIGH TIDE CYCLE.
&&
.RIP CURRENTS...
A HIGH RISK OF DANGEROUS RIP CURRENTS TODAY AND THIS EVE WITH
BREEZY NE FLOW AND A NEAR FULL MOON.
THE THREAT FOR RIP CURRENTS ON WEDNESDAY IS EXPECTED TO BE AT
LEAST MODERATE.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...COASTAL FLOOD ADVISORY UNTIL 2 PM EDT WEDNESDAY FOR NJZ012>014-
020-022>027.
COASTAL FLOOD ADVISORY UNTIL 4 PM EDT WEDNESDAY FOR NJZ016-021.
DE...COASTAL FLOOD ADVISORY UNTIL 2 PM EDT WEDNESDAY FOR DEZ003-004.
COASTAL FLOOD ADVISORY UNTIL 4 PM EDT WEDNESDAY FOR DEZ001-002.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL NOON EDT WEDNESDAY FOR ANZ450>455.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ430-
431.
&&
$$
SYNOPSIS...KLEIN
NEAR TERM...GAINES/O`HARA
SHORT TERM...O`HARA
LONG TERM...KLEIN
AVIATION...KLEIN/O`HARA
MARINE...KLEIN/O`HARA
TIDES/COASTAL FLOODING...KLINE
RIP CURRENTS...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1210 PM EDT TUE SEP 9 2014
.SYNOPSIS...
AN AREA OF LOW PRESSURE DEVELOPING ALONG THE NORTH CAROLINA COAST
TODAY WILL DRIFT NORTHEASTWARD OFF THE MID-ATLANTIC COAST THROUGH
WEDNESDAY. A COLD FRONT WILL APPROACH FROM THE WEST THURSDAY BEFORE
MOVING THROUGH THE AREA THURSDAY NIGHT. THE FRONT WILL STALL TO OUR
SOUTH WHILE HIGH PRESSURE BUILDS IN FROM THE NORTHERN PLAINS FRIDAY.
THE STALLED BOUNDARY WILL RETURN NORTHWARD TOWARD THE REGION
SATURDAY BEFORE THE FRONT GRADUALLY MOVES OFFSHORE LATE IN THE
WEEKEND. HIGH PRESSURE IS EXPECTED TO BUILD BACK INTO THE MID-
ATLANTIC STATES BY MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LOW PRESSURE OFF THE MID-ATLANTIC COAST WILL MOVE UP INTO THE
WATERS OFF TIDEWATER VA LATER TODAY. IT APPEARS FROM THE LATEST
MODELS THAT ONLY SRN- MOST NJ AND THE DELMARVA WILL BE THE ONLY
AREAS THAT WILL GET ANY PCPN FROM THIS SYSTEM. POPS HAVE BEEN
SCALED BACK ONLY INDICATING A SLIGHT TO LOW CHANCE POP FROM PHL
EAST WITH THE 12:30 PM UPDATE. THE HRRR WAS OVERDONE WITH REALITY
THIS MORNING ON THE POPS WITH THE RAP HAVING A BETTER HANDLE ON
SHORT TERM CONDITIONS. CLOUDS AND A MOIST E/NE FLOW WILL BE ACROSS
MOST OF THE REST OF THE AREA. WE HAVE FOLLOWED THE GFS MODEL WITH
THIS FCST...ALTHOUGH THE NAM AND 12Z EC ARE ALL REASONABLY CLOSE
WITH REGARDS TO THE TRACK AND EFFECTS WITH THE LOW. HIGHS
TODAY...MOSTLY LOW/MID 70S WITH A FEW UPPER 60S OVER THE SRN
POCONOS. MINOR ADJUSTMENTS TO THE TEMPERATURES WERE MADE WITH BOTH
THE MORNING AND AFTERNOON UPDATE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
THE LOW WILL CONTINUE TO MOVE NE AND IT WILL BE WELL E OF DEL BY 12Z
WED. CLOUDS WILL REMAIN ACROSS MOST OF THE AREA TONIGHT...WITH
SHOWERS OR LIGHT RAIN ACROSS MOSTLY THE SRN COASTAL AREAS. E/NE
WINDS WILL CONTINUE ACROSS THE AREA WITH A COOL/DAMPNESS EXPECTED
ALONG THE COAST. TEMPS TONIGHT...LOW/MID 50S ACROSS THE NORTH WITH
SOME BREAKS POSSIBLE RANGING TO THE LOW/MID 60S ELSEWHERE.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
00Z MODEL GUIDANCE IS IN FAIRLY GOOD AGREEMENT WITH TIMING OF H5
SHORTWAVE TROUGH ON WEDNESDAY. LIFT AHEAD OF THIS MID-LVL TROUGH AND
IN LEFT-EXIT REGION OF UPPER-LVL JET STREAK WILL BE PROGRESSING
DOWNSTREAM OF THE AREA DURING THE MORNING. THE COASTAL LOW IS
FORECAST TO MEANDER OFF THE DELMARVA COAST DURING THIS TIME.
ENHANCED WRAP-AROUND MOISTURE FROM THE ATLANTIC OCEAN WOULD MOST
LIKELY REMAIN OFFSHORE GIVEN THE POSITION OF THE COASTAL LOW. RAIN
MAY LINGER NEAR THE DE AND SOUTHERN NJ COAST DURING THE MORNING. A
DRYING TREND IS EXPECTED FOR THE AFTERNOON WITH THE COASTAL LOW
DRIFTING FARTHER OFF THE MID-ATLANTIC COAST WHILE THE UPPER DYNAMICS
ASSOCIATED WITH THE SHORTWAVE TROUGH SHIFTS FARTHER OFFSHORE.
FAVORED THE COOLER MAV GUIDANCE FOR MAX TEMPS WEDNESDAY AS MARINE
STRATOCU MAY BE STUBBORN TO ERODE UNDER THE PERSISTENCE OF ONSHORE
FLOW IN THE BOUNDARY LAYER.
A WEAK RIDGE OF HIGH PRESSURE IS EXPECTED TO BUILD OVER THE EASTERN
SEABOARD WEDNESDAY NIGHT WHILE THE COASTAL LOW CONTINUES TO DRIFT
FARTHER OFF THE NORTHERN MID-ATLANTIC COAST. WILL NEED TO MONITOR
FOR THE POTENTIAL OF STRATUS AND/OR FOG DEVELOPMENT (PARTICULARLY AT
LOCATIONS CLOSER TO THE COAST) WITH RESIDUAL MARINE AIR OVERHEAD.
FARTHER WEST INTO PA, LOW-LEVEL WINDS DO BEGIN TO VEER OUT OF THE
SOUTH OVERNIGHT AHEAD OF A COLD FRONT THAT IS APPROACHING FROM THE
WEST.
AFOREMENTIONED COLD FRONT IS EXPECTED TO MOVE INTO THE MID-ATLANTIC
AND NORTHEAST STATES ON THURSDAY. THE 00Z GFS WAS ABOUT 6 HOURS
FASTER WITH THE FROPA THAN THE 00Z NAM/ECMWF/CMC AND GEFS MEAN. A
SLOWER SOLUTION WOULD BE FAVORED IN THIS SETUP WITH THE DEEPENING
CYCLONE EXPECTED TO CUT WELL TO OUR NORTHWEST ACROSS QUEBEC.
AFTERNOON POPS HIGHEST IN THE PA ZONES, WHERE TIMING OF FROPA WOULD
COINCIDE MORE FAVORABLY WITH PEAK HEATING HOURS. INTERESTINGLY, BOTH
THE 00Z NAM/GFS OPERATIONAL RUNS SHOW AN IMPRESSIVE WARM CONVEYOR
BELT WITH PWATS WITHIN THE WELL-DEFINED ATMOSPHERIC RIVER NEAR +3SD
OVER THE MID-ATLANTIC COAST THURSDAY EVENING. THERE IS SOME DEGREE
OF A THREAT FOR HEAVY RAINFALL IN THUNDERSTORMS, BUT THE THREAT OF
MAY BE MORE LOCALIZED ACROSS OUR AREA DUE TO A LACK OF SYNOPTIC LIFT
NOTED IN THE MID AND UPPER LEVELS.
A BROAD AREA OF HIGH PRESSURE OVER THE NORTHERN PLAINS BUILDS
EASTWARD INTO THE AREA ON FRIDAY. THE COLD FRONT THAT MOVES THROUGH
THE REGION THURSDAY NIGHT WILL STALL TO OUR SOUTH ON FRIDAY. DRY
CONDITIONS AND SLIGHTLY BELOW NORMAL TEMPS ARE EXPECTED TO CLOSE
OUT THE WORK WEEK.
A NORTHERN-STREAM SHORTWAVE TROUGH IS FORECAST TO TRACK THRU THE
GREAT LAKES ON SATURDAY. SOUTHERLY FLOW STRENGTHENING AHEAD OF THIS
SYSTEM WOULD ALLOW THE STALLED FRONTAL BOUNDARY TO OUR SOUTH TO LIFT
NORTHWARD TOWARD OUR AREA. THERE IS A POTENTIAL FOR THE WEEKEND TO
START OUT WET UNDER THIS SETUP AS WARM AND MOIST AIR OVERRUNS THE
BOUNDARY. MODELS ARE HINTING AT THE POTENTIAL FOR A SECONDARY WAVE
OF LOPRES TO DEVELOP NEAR THE MID-ATLANTIC COAST. IF LOPRES DEVELOPS
CLOSE ENOUGH TO THE COAST, THE FRONT WOULD BE SLOWER TO PUSH
OFFSHORE AND PRECIP COULD LINGER INTO SUNDAY (ESPECIALLY AT COASTAL
LOCATIONS). POPS WERE KEPT AT 20-30 PERCENT WITH HIGH FORECAST
UNCERTAINTY. TEMPS WILL BE SLIGHTLY BELOW NORMAL THIS WEEKEND OWING
TO THE CLOUD COVER AND ONSHORE FLOW.
HIGH PRESSURE BUILDS BACK IN FROM THE WEST BY EARLY NEXT WEEK.
&&
.AVIATION /16Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THE 06Z TAFS WERE SOMEWHAT MORE OPTIMISTIC WITH REGARDS TO
CIGS/VSBYS AT OUR TERMINALS. IT APPEARS THAT THE GFS/NAM ARE KEEPING
MUCH OF THE POORER CONDITIONS CLOSER TO THE LOW WHICH WILL PASS
SOUTH/EAST OF THE DEL VALLEY TAF SITES. KMIV/KACY WILL HAVE MORE OF
AN IMPACT...BUT STILL NOT AS LOW AS PREVIOUSLY FCST. WINDS WILL
INCREASE FROM THE E/ENE TODAY WITH SPEEDS 5 TO 10 KTS INLAND AND 10
TO 15 KTS ACROSS SRN NJ AND INTO DEL. IMPROVEMENT BACK TO VFR
EXPECTED IN MOST AREAS THIS AFTERNOON...THEN GUIDANCE SHOWING LOWER
CONDITIONS TONIGHT.
OUTLOOK...
WEDNESDAY...LOW CLOUDS AND MVFR CIGS MAY LINGER INTO WED MRNG,
ESPECIALLY NEAR THE COAST. CIGS IMPROVE TO VFR WED AFTN.
WEDNESDAY NIGHT...VFR IN THE EVE. LOW CLOUDS AND FOG MAY DEVELOP
OVERNIGHT.
THURSDAY AND THURSDAY NIGHT...SHRA AND TSRA LIKELY IN THE AFTN AT
RDG/ABE. THIS ACTIVITY MAY HOLD OFF FARTHER EAST UNTIL THIS EVE
AND OVNGT WHEN A COLD FRONT MOVES THRU. FROPA WILL BE MARKED BY
WIND SHIFT FROM S TO NW.
FRIDAY AND FRIDAY NIGHT...VFR
SATURDAY...CHANCE OF SHRA WITH SUB-VFR CONDITIONS POSSIBLE.
&&
.MARINE...
WE WILL KEEP THE SCA FLAG ACROSS THE WATERS TODAY AND TONIGHT. GUSTS
IN THE 25 TO 30 KNOT RANGE EXPECTED ON THE OCEAN AND MORE IN THE 20
TO 25 KNOT RANGE FOR DEL BAY. SCA IS KINDA MARGINAL THERE. DECENT
SEAS 6 TO 8 FT ON THE OCEAN...AND A FEW HIGHER SEAS ACROSS THE MOUTH
OF DEL BAY. SHOWERS MOSTLY SOUTH/EAST TODAY AND EARLY TONIGHT.
OUTLOOK...
WEDNESDAY MORNING...SCA EXTENDED INTO WED MRNG WITH NE WINDS AROUND
A COASTAL LOW GUSTING TO 25 KT. SEAS BETWEEN 5-7 FT ARE EXPECTED.
WEDNESDAY AFTERNOON AND WEDNESDAY NIGHT...THE PRESSURE GRADIENT
GRADUALLY WEAKENS AND WINDS SHOULD DECREASE TO BELOW SCA LEVELS BY
THE AFTN. HOWEVER, THE SCA MAY NEED TO BE EXTENDED DURING THIS TIME
AS SEAS WILL TAKE TIME TO SUBSIDE. THE LATEST GUIDANCE SUGGESTS
WAVES OF 4-5 FT FOR THIS PERIOD.
THURSDAY...SOUTHERLY WINDS INCREASE AHEAD OF A FRONT BUT SHOULD
REMAIN BELOW SCA LVLS.
THURSDAY NIGHT AND FRIDAY MORNING...COLD FRONT MOVES THRU THE WATERS
THURSDAY NIGHT. STORMS MAY PRODUCE LOCALLY GUSTY WINDS JUST AHEAD OF
THE FRONT DURING THE EVE. PRESSURE SURGE IN WAKE OF FROPA MAY
PRODUCE A BRIEF PERIOD OF NW WINDS GUSTING TO NEAR SCA THRESHOLD
LATE THURSDAY NIGHT INTO FRIDAY MORNING.
FRIDAY AFTERNOON THROUGH SATURDAY....NO MARINE HEADLINES ARE
EXPECTED.
&&
.TIDES/COASTAL FLOODING...
ONSHORE FLOW TO CONTINUE TODAY AND TONIGHT. MORE MINOR TIDAL
FLOODING IS EXPECTED...SPOTTY WITH THE MORNING HIGH TIDE AND A BIT
MORE WIDESPREAD WITH THE EVENING HIGH TIDE. A CFW ADVISORIES WAS
ISSUED TO COVER THE NEXT TWO HIGH TIDE CYCLES.
WITH A COASTAL LOW MEANDERING JUST OFFSHORE AND ONSHORE FLOW
CONTINUING, THE THREAT OF MINOR COASTAL FLOODING MAY CONTINUE INTO
WEDNESDAY`S HIGH TIDE CYCLES.
&&
.RIP CURRENTS...
A HIGH RISK OF DANGEROUS RIP CURRENTS TODAY AND THIS EVE WITH
BREEZY NE FLOW AND A NEAR FULL MOON.
THE THREAT FOR RIP CURRENTS ON WEDNESDAY IS EXPECTED TO BE AT
LEAST MODERATE.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...COASTAL FLOOD ADVISORY UNTIL 2 PM EDT WEDNESDAY FOR NJZ012>014-
020-022>027.
COASTAL FLOOD ADVISORY UNTIL 4 PM EDT WEDNESDAY FOR NJZ016-021.
DE...COASTAL FLOOD ADVISORY UNTIL 2 PM EDT WEDNESDAY FOR DEZ003-004.
COASTAL FLOOD ADVISORY UNTIL 4 PM EDT WEDNESDAY FOR DEZ001-002.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL NOON EDT WEDNESDAY FOR ANZ450>455.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ430-
431.
&&
$$
SYNOPSIS...KLEIN
NEAR TERM...GAINES/O`HARA
SHORT TERM...O`HARA
LONG TERM...KLEIN
AVIATION...KLEIN/O`HARA
MARINE...KLEIN/O`HARA
TIDES/COASTAL FLOODING...
RIP CURRENTS...
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
928 PM EDT WED SEP 10 2014
.UPDATE...MUCH LESS CONVECTION THIS AFTERNOON AND EVE DUE TO DRY AND
MORE STABLE AIR ALOFT. A FEW REMAINING SHOWERS ACROSS THE SUWANNEE
VALLEY WILL CONTINUE TO MOVE WEST AND WEAKEN. WILL KEEP ISOLATED POPS
GOING TONIGHT FOR THE COASTAL WATERS AND LOWER ACROSS THE SUWANNEE
VALLEY THE NEXT COUPLE OF HOURS. ADEQUATE LOW LEVEL MOISTURE ALONG
WITH LIGHT WINDS AND MOSTLY CLEAR SKIES RESULTS IN PATCHY LATE NIGHT
DENSE FOG ACROSS THE INLAND AREAS.
&&
.AVIATION...
ALTHOUGH CONDITIONS APPEAR FAVORABLE FOR FOG DEVELOPMENT
OVERNIGHT...THE MAJORITY OF THE FOG TOOLS SEEM TO BE DOWNPLAYING
THIS THREAT. IN FACT...THE HRRR DOES NOT REALLY INDICATE MUCH IN THE
WAY OF FOG AT ALL. NEVERTHELESS...GIVEN THE CONDITIONS...WOULD
EXPECT AT LEAST PATCHY SHALLOW FOG DEVELOPMENT LATE
TONIGHT...POSSIBLY EVEN SOME PATCHY DENSE FOG AT THE MORE PRONE
LOCATIONS SUCH AS VQQ. OTHERWISE...VFR WILL PREVAIL THROUGH THIS TAF
PERIOD.
&&
.MARINE...NO HEADLINES. SOUTHEAST WINDS 10 KNOTS. SEAS 2 TO 3 FEET.
ISOLATED SHOWERS AND THUNDERSTORMS.
RIP CURRENTS: LOW RISK.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 71 91 74 92 / 20 30 20 20
SSI 74 85 75 85 / 10 10 10 10
JAX 73 89 73 88 / 10 20 10 20
SGJ 74 86 74 85 / 10 10 10 10
GNV 71 89 71 89 / 20 30 20 20
OCF 71 89 72 89 / 20 30 30 20
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
SHULER/PETERSON/WALSH
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
840 PM EDT WED SEP 10 2014
.UPDATE (REST OF TONIGHT AND THURSDAY)...
00Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS THE FIRST SIGNIFICANT
AUTUMN INTRUSION OF AIR HAS ARRIVED OVER PORTIONS OF THE NORTHERN
ROCKIES/NORTHERN PLAINS/UPPER MIDWEST WITH A BIG DIP IN THE NORTHERN
STREAM FLOW. THIS BIG CHANGE IN THE SEASONS HOWEVER IS NOT IN OUR
FUTURE...AT LEAST NOT QUITE YET. OUR FORECAST AREA RESIDES BETWEEN
AND ELONGATED AREA OF UPPER RIDGING EXTENDING FROM THE SOUTHERN
PLAINS TO THE GA/SC COAST...AND A WEAK UPPER DISTURBANCE LOCATED
NEAR THE BAHAMAS. A MUCH DRIER PUSH OF MID/UPPER LEVEL AIR CAN BE
SEEN CLEARLY ON WV IMAGERY ROUNDING THE EASTERN PERIPHERY OF THE
UPPER RIDGE INTO NORTHERN FLORIDA. THIS DRYING OF THE UPPER LEVEL
AIRMASS CAN BE SEEN CLEARLY WHEN ONE COMPARES THE 00Z KTBW
SOUNDING...WHICH IS MOIST THROUGH THE EXTENT OF THE TROP...WITH THE
KJAX SOUNDING WITH SHOWS SIGNIFICANTLY LARGER DEWPOINT DEPRESSIONS
ABOVE 600MB. THERE IS GOOD AGREEMENT AMONG THE MODEL SUITE THAT
THIS SURGE OF DRIER AIR ALOFT WILL AT LEAST REACH THE CENTRAL
FLORIDA PENINSULA FOR THURSDAY...AND POSSIBLY PENETRATE SOUTHWARD AS
FAR AS AROUND CHARLOTTE COUNTY. THE OVERALL LOWER LEVEL SYNOPTIC
PATTERN WILL NOT CHANGE MUCH THROUGH THURSDAY FROM WHAT OCCURRED
TODAY...HOWEVER...WITH THE LESS FAVORABLE COLUMN TO SUPPORT DEEP
CONVECTION ALOFT...THE BEST CHANCES FOR SCT AFTERNOON STORMS SHOULD
CERTAINLY BE SOUTH OF THE I-4 CORRIDOR...AND MOST LIKELY DOWN ALONG
THE MOISTURE GRADIENT OVER OUR FAR SOUTHERN ZONES OF CHARLOTTE/LEE
COUNTIES.
ANYWAY...DID THIS BACKWARDS AND TALKED ABOUT THURSDAY BEFORE THE
REST OF TONIGHT. FOR THE REST OF TONIGHT...STORMS HAVE PUSHED
OFFSHORE FOR THE NATURE COAST AND DOWN THROUGH THE TAMPA BAY
REGION...AND THE REST OF THE OVERNIGHT SHOULD BE SEASONABLE AND DRY.
STILL SEEING A FEW WIDELY SCT SHOWERS MIGRATING WESTWARD IN THE FLOW
BETWEEN FORT MYERS AND LAKE OKEECHOBEE. A BRIEF SHOWER CAN NOT BE
RULED OUT WELL TO THE SOUTH OF TAMPA BAY THROUGH THE NEXT HOUR OR
TWO...BUT EVEN FOR THESE SOUTHERN ZONES...THE LOSS OF DIURNAL
HEATING SHOULD KEEP ANY SHOWERS FEW AND FAR BETWEEN...WITH A
WEAKENING TREND INTO THE LATER EVENING HOURS. BEYOND 11 PM OR
SO...ALL LAND ZONES SHOULD SEE A DRY OVERNIGHT.
&&
.PREVIOUS DISCUSSION (THURSDAY)...
THURSDAY...THE MID/UPPER RIDGE CONTINUES TO BUILD FROM THE WEST TO A
POSITION OVER THE NORTHERN PART OF THE STATE WITH THE SURFACE RIDGE
REMAINING NORTH OF THE AREA. THE POSITION OF THE MID/UPPER RIDGE
WILL HELP TO LOWER POPS A BIT FOR THE NORTHERN HALF OF THE FORECAST
AREA AND WILL SHOW JUST ISOLATED THUNDERSTORMS. SHOULD SEE THE WEST
COAST SEA BREEZE MAKE IT A BIT FARTHER EASTWARD THAN IT DID
TODAY...WHICH WILL HELP PROVIDE FOCUS FOR SCATTERED THUNDERSTORMS IN
THE AFTERNOON AND EVENING...ESPECIALLY FROM THE TAMPA BAY AREA
SOUTHWARD.
&&
.AVIATION...
VFR CONDITIONS PREVAIL ACROSS THE REGION LATE THIS EVENING. STORMS
HAVE PUSHED OFF THE COAST AROUND THE TAMPA BAY AREA AND NO LONGER
EXPECT ANY CHANCE OF CONVECTIVE RESTRICTION THROUGH THE NIGHT. MAY
STILL SEE A BRIEF SHOWER THROUGH 02Z DOWN TOWARD
KFMY/KRSW/KPGD...BUT ANY SHOWERS WILL BE QUICK AND THEN VFR FOR THE
REMAINDER OF THE OVERNIGHT. THURSDAY MORNING WILL BE QUIET WITH A
DEVELOPING CUMULUS FIELD INTO THE EARLY AFTERNOON. SCT STORMS WILL
BREAK OUT BY MID AFTERNOON WITH THE GREATEST POTENTIAL FOR A PASSING
STORM BEING SOUTH OF OF TAMPA BAY REGION.
&&
.MARINE...
A WEAK TROPICAL DISTURBANCE FROM THE BAHAMAS IS BEING WATCHED
CLOSELY AS IT IS FORECAST TO MOVE ACROSS SOUTH FLORIDA AND THEN
INTO THE GULF OVER THE NEXT COUPLE OF DAYS. CHANCES FOR ANY ENHANCED
WINDS AND THUNDERSTORMS SHOULD BE GREATEST SOUTH OF TAMPA BAY LATER
IN THE WEEK. THE NATIONAL HURRICANE CENTER HAS A 30 PERCENT CHANCE
OF CYCLONE FORMATION IN THE NEXT FIVE DAYS...AND THE SYSTEM WILL
CONTINUE TO BE MONITORED...ALTHOUGH DEVELOPMENT...IF ANY...WILL BE
SLOW TO OCCUR.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 76 91 77 90 / 20 20 20 40
FMY 74 91 75 90 / 30 40 20 50
GIF 73 92 74 90 / 10 30 10 40
SRQ 75 90 75 90 / 30 30 30 40
BKV 72 91 72 92 / 20 20 20 30
SPG 78 90 78 90 / 30 20 30 40
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
EVENING UPDATE...MROCZKA
PREVIOUS DISCUSSION...CARLISLE
MARINE...007/DOUGHERTY
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
605 PM EDT TUE SEP 9 2014
.SYNOPSIS...
A SURFACE LOW OVER EASTERN NORTH CAROLINA WILL SLOWLY MOVE
NORTHEAST AS HIGH PRESSURE CONTINUES TO RIDGE INTO THE CAROLINAS
AND GEORGIA FROM THE NORTH. DRIER AIR WILL FILTER INTO THE REGION
THROUGH WEDNESDAY. A COLD FRONT WILL MOVE INTO THE AREA THURSDAY
NIGHT AND FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
SOME BREAKS IN THE CLOUDS FROM THE WEST AS SURFACE HIGH PRESSURE
CONTINUES TO RIDGE FROM THE NORTH. THERE MAY STILL BE A SPRINKLE
OR TWO WHERE CLOUDS REMAIN BUT OTHERWISE RAIN CHANCES ARE VERY LOW
FOR THE EVENING AND OVERNIGHT HOURS. NOCTURNAL COOLING WITH LIGHT
WIND AND LINGERING LOW-LEVEL MOISTURE PLUS DRY AIR ALOFT SHOULD
HELP SUPPORT AREAS OF FOG LATE TONIGHT. OVERNIGHT LOWS WILL BE
MAINLY IN THE MIDDLE 60S.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
WEAK HIGH PRESSURE WILL BE IN CONTROL OF THE REGION FOR WEDNESDAY
AND WEDNESDAY NIGHT THEN PUSH INTO THE ATLANTIC BASIN THURSDAY AS
THE NEXT COLD FRONT TRACKS TOWARD THE AREA. WITH THE HIGH PRESSURE
OVER THE FORECAST AREA ON WEDNESDAY DRIER AIR WILL WORK INTO THE
REGION WITH PWAT VALUES FALLING THROUGH THE DAY AND REACHING 1.3
INCHES BY EARLY EVENING. THE DRIER AIR ALONG WITH TEMPERATURES
STRUGGLING TO REACH CONVECTIVE TEMPERATURES IN THE UPPER 80S WILL
PRECLUDE SHOWER AND THUNDERSTORM DEVELOPMENT THROUGH WEDNESDAY
NIGHT. THE SCENARIO WILL BEGIN CHANGING ON THURSDAY AS THE COLD
FRONT MOVES THROUGH THE OHIO AND TN VALLEYS AND INTO THE UPSTATE
THURSDAY NIGHT. THIS WILL PRODUCE INCREASING CLOUDS AND WITH
SOUTHERLY WINDS PUSHING MOISTURE BACK INTO THE AREA PWAT VALUES
WILL BEGIN TO RISE. ALTHOUGH MODELS INDICATE POTENTIAL FOR SHOWERS
AND THUNDERSTORMS THURSDAY AFTERNOON HAVE REMAINED WITH SLIGHT
CHANCE POPS AS DRY AIR ALOFT WILL REMAIN ALONG WITH A MID LEVEL
CAP. POPS WILL INCREASE SLOWLY THURSDAY NIGHT AS THE FRONT MOVES
CLOSER THE THE FORECAST AREA WITH THE BEST CHANCE ACROSS THE
WESTERN MIDLANDS. TEMPERATURES WEDNESDAY AND THURSDAY WILL BE IN
THE UPPER 80S TO LOWER 90S WITH OVERNIGHT LOWS IN THE UPPER 60S TO
LOWER 70S.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
MODELS CONTINUE IN GOOD AGREEMENT THROUGH THE LONG TERM. COLD
FRONT WILL SLOW AS IT MOVES IN THE FORECAST AREA ON FRIDAY AND
STALL ACROSS THE AREA FRIDAY NIGHT THROUGH TUESDAY. WITH HIGH
PRESSURE BUILDING INTO THE SOUTHERN GREAT LAKES REGION SATURDAY
COOLER AND DRIER AIR WILL BEGIN MOVING SOUTHWARD THROUGH THE
EASTERN US AND BEGIN FILTERING INTO THE FORECAST AREA LATE IN THE
WEEKEND. WITH THE FRONT ACROSS THE REGION CHANCES OF SHOWERS AND
THUNDERSTORMS WILL RETURN TO THE FORECAST WITH THE HIGHEST POPS
CURRENTLY EXPECTED FOR FRIDAY THROUGH SATURDAY...WITH SOME
UNCERTAINTY IN POPS FOR MONDAY AND TUESDAY. TEMPERATURES THROUGH
THE LONG TERM WILL BE NEAR NORMAL THROUGH FRIDAY NIGHT WITH BELOW
NORMAL EXPECTED FOR SATURDAY WITH BELOW NORMAL FOR SUNDAY THROUGH
TUESDAY.
&&
.AVIATION /22Z TUESDAY THROUGH SUNDAY/...
HIGH LOW-LEVEL MOISTURE IS TRAPPED BELOW AN INVERSION. THIS
MOISTURE IS IN THE NORTHEAST FLOW BETWEEN A PRESSURE RIDGE ALONG
THE MOUNTAINS AND LOW PRESSURE OFF THE NORTH CAROLINA AND VIRGINIA
COASTS. THE MODELS DISPLAY THE LOW SHIFTING FARTHER NORTHEASTWARD WITH
MOISTURE BECOMING MORE SHALLOW. THE DECREASE IN MOISTURE WITH SOME
HEATING AND MIXING SHOULD HELP CAUSE IMPROVING CEILINGS. WE USED
THE RAP TIME-HEIGHT DISPLAYS AND GFS LAMP FOR THE TIMING OF
IMPROVING CEILINGS. EXPECT VFR CONDITIONS DEVELOPING THIS
AFTERNOON AND CONTINUING THIS EVENING. NOCTURNAL COOLING WITH LIGHT
WIND AND LINGERING LOW-LEVEL MOISTURE PLUS DRY AIR ALOFT SHOULD
HELP SUPPORT FOG DURING THE EARLY MORNING HOURS WEDNESDAY. MOST
OF THE NAM AND GFS MOS INDICATE IFR CONDITIONS DEVELOPING. HEATING
AND MIXING SHOULD DISSIPATE THE FOG LATER IN THE MORNING. USED THE
GFS LAMP FOR THE TIMING.
.EXTENDED AVIATION OUTLOOK...WIDESPREAD STRATUS AND FOG MAY OCCUR
DURING THE EARLY MORNING HOURS THURSDAY. THUNDERSTORMS ARE POSSIBLE
THURSDAY NIGHT AND FRIDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
237 PM EDT TUE SEP 9 2014
.SYNOPSIS...
A SURFACE LOW OVER EASTERN NORTH CAROLINA WILL SLOWLY MOVE
NORTHEAST AS HIGH PRESSURE CONTINUES TO RIDGE INTO THE CAROLINAS
AND GEORGIA FROM THE NORTH. DRIER AIR WILL FILTER INTO THE REGION
THROUGH WEDNESDAY. A COLD FRONT WILL MOVE INTO THE AREA THURSDAY
NIGHT AND FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
HIGH LOW-LEVEL MOISTURE IS TRAPPED BELOW AN INVERSION. THIS
MOISTURE IS IN THE NORTHEAST FLOW BETWEEN A PRESSURE RIDGE ALONG
THE MOUNTAINS AND LOW PRESSURE OFF THE NORTH CAROLINA AND VIRGINIA
COASTS. THE MODELS DISPLAY THE LOW SHIFTING FARTHER NORTHEASTWARD WITH
MOISTURE BECOMING MORE SHALLOW IN THE FORECAST AREA. THE DECREASE IN
MOISTURE WITH SOME HEATING AND MIXING SHOULD HELP CAUSE BREAKS IN
THE CLOUDINESS. EXPECT TEMPERATURES WILL WARM INTO THE LOWER 80S
NORTH AND MIDDLE 80S SOUTH. THE SHOWER CHANCE IS LOW BECAUSE OF
SHALLOW MOISTURE. THE HIGH-RESOLUTION MODELS MAINTAIN DRY CONDITIONS.
HIGH PRESSURE RIDGING INTO THE FORECAST AREA WILL DOMINATE TONIGHT.
NOCTURNAL COOLING WITH LIGHT WIND AND LINGERING LOW-LEVEL MOISTURE
PLUS DRY AIR ALOFT SHOULD HELP SUPPORT AREAS OF FOG LATE TONIGHT.
THE TEMPERATURE GUIDANCE WAS CONSISTENT.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
WEAK HIGH PRESSURE WILL BE IN CONTROL OF THE REGION FOR WEDNESDAY
AND WEDNESDAY NIGHT THEN PUSH INTO THE ATLANTIC BASIN THURSDAY AS
THE NEXT COLD FRONT TRACKS TOWARD THE AREA. WITH THE HIGH PRESSURE
OVER THE FORECAST AREA ON WEDNESDAY DRIER AIR WILL WORK INTO THE
REGION WITH PWAT VALUES FALLING THROUGH THE DAY AND REACHING 1.3
INCHES BY EARLY EVENING. THE DRIER AIR ALONG WITH TEMPERATURES
STRUGGLING TO REACH CONVECTIVE TEMPERATURES IN THE UPPER 80S WILL
PRECLUDE SHOWER AND THUNDERSTORM DEVELOPMENT THROUGH WEDNESDAY
NIGHT. THE SCENARIO WILL BEGIN CHANGING ON THURSDAY AS THE COLD
FRONT MOVES THROUGH THE OHIO AND TN VALLEYS AND INTO THE UPSTATE
THURSDAY NIGHT. THIS WILL PRODUCE INCREASING CLOUDS AND WITH
SOUTHERLY WINDS PUSHING MOISTURE BACK INTO THE AREA PWAT VALUES
WILL BEGIN TO RISE. ALTHOUGH MODELS INDICATE POTENTIAL FOR SHOWERS
AND THUNDERSTORMS THURSDAY AFTERNOON HAVE REMAINED WITH SLIGHT
CHANCE POPS AS DRY AIR ALOFT WILL REMAIN ALONG WITH A MID LEVEL
CAP. POPS WILL INCREASE SLOWLY THURSDAY NIGHT AS THE FRONT MOVES
CLOSER THE THE FORECAST AREA WITH THE BEST CHANCE ACROSS THE
WESTERN MIDLANDS. TEMPERATURES WEDNESDAY AND THURSDAY WILL BE IN
THE UPPER 80S TO LOWER 90S WITH OVERNIGHT LOWS IN THE UPPER 60S TO
LOWER 70S.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
MODELS CONTINUE IN GOOD AGREEMENT THROUGH THE LONG TERM. COLD
FRONT WILL SLOW AS IT MOVES IN THE FORECAST AREA ON FRIDAY AND
STALL ACROSS THE AREA FRIDAY NIGHT THROUGH TUESDAY. WITH HIGH
PRESSURE BUILDING INTO THE SOUTHERN GREAT LAKES REGION SATURDAY
COOLER AND DRIER AIR WILL BEGIN MOVING SOUTHWARD THROUGH THE
EASTERN US AND BEGIN FILTERING INTO THE FORECAST AREA LATE IN THE
WEEKEND. WITH THE FRONT ACROSS THE REGION CHANCES OF SHOWERS AND
THUNDERSTORMS WILL RETURN TO THE FORECAST WITH THE HIGHEST POPS
CURRENTLY EXPECTED FOR FRIDAY THROUGH SATURDAY...WITH SOME
UNCERTAINTY IN POPS FOR MONDAY AND TUESDAY. TEMPERATURES THROUGH
THE LONG TERM WILL BE NEAR NORMAL THROUGH FRIDAY NIGHT WITH BELOW
NORMAL EXPECTED FOR SATURDAY WITH BELOW NORMAL FOR SUNDAY THROUGH
TUESDAY.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
HIGH LOW-LEVEL MOISTURE IS TRAPPED BELOW AN INVERSION. THIS
MOISTURE IS IN THE NORTHEAST FLOW BETWEEN A PRESSURE RIDGE ALONG
THE MOUNTAINS AND LOW PRESSURE OFF THE NORTH CAROLINA AND VIRGINIA
COASTS. THE MODELS DISPLAY THE LOW SHIFTING FARTHER NORTHEASTWARD WITH
MOISTURE BECOMING MORE SHALLOW. THE DECREASE IN MOISTURE WITH SOME
HEATING AND MIXING SHOULD HELP CAUSE IMPROVING CEILINGS. WE USED
THE RAP TIME-HEIGHT DISPLAYS AND GFS LAMP FOR THE TIMING OF
IMPROVING CEILINGS. EXPECT VFR CONDITIONS DEVELOPING THIS
AFTERNOON AND CONTINUING THIS EVENING. NOCTURNAL COOLING WITH LIGHT
WIND AND LINGERING LOW-LEVEL MOISTURE PLUS DRY AIR ALOFT SHOULD
HELP SUPPORT FOG DURING THE EARLY MORNING HOURS WEDNESDAY. MOST
OF THE NAM AND GFS MOS INDICATE IFR CONDITIONS DEVELOPING. HEATING
AND MIXING SHOULD DISSIPATE THE FOG LATER IN THE MORNING. USED THE
GFS LAMP FOR THE TIMING.
.EXTENDED AVIATION OUTLOOK...WIDESPREAD STRATUS AND FOG MAY OCCUR
DURING THE EARLY MORNING HOURS THURSDAY. THUNDERSTORMS ARE POSSIBLE
THURSDAY NIGHT AND FRIDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
136 PM EDT TUE SEP 9 2014
.SYNOPSIS...
A SURFACE LOW OVER EASTERN NORTH CAROLINA WILL SLOWLY MOVE
NORTHEAST AS HIGH PRESSURE CONTINUES TO RIDGE INTO THE CAROLINAS
AND GEORGIA FROM THE NORTH. DRIER AIR WILL FILTER INTO THE REGION
THROUGH WEDNESDAY. A COLD FRONT WILL MOVE INTO THE AREA THURSDAY
NIGHT AND FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
HIGH LOW-LEVEL MOISTURE IS TRAPPED BELOW AN INVERSION. THIS
MOISTURE IS IN THE NORTHEAST FLOW BETWEEN A PRESSURE RIDGE ALONG
THE MOUNTAINS AND LOW PRESSURE OFF THE NORTH CAROLINA AND VIRGINIA
COASTS. THE MODELS DISPLAY THE LOW SHIFTING FARTHER NORTHEASTWARD WITH
MOISTURE BECOMING MORE SHALLOW IN THE FORECAST AREA. THE DECREASE IN
MOISTURE WITH SOME HEATING AND MIXING SHOULD HELP CAUSE BREAKS IN
THE CLOUDINESS. EXPECT TEMPERATURES WILL WARM INTO THE LOWER 80S
NORTH AND MIDDLE 80S SOUTH. THE SHOWER CHANCE IS LOW BECAUSE OF
SHALLOW MOISTURE. THE HIGH-RESOLUTION MODELS MAINTAIN DRY CONDITIONS.
HIGH PRESSURE RIDGING INTO THE FORECAST AREA WILL DOMINATE TONIGHT.
NOCTURNAL COOLING WITH LIGHT WIND AND LINGERING LOW-LEVEL MOISTURE
PLUS DRY AIR ALOFT SHOULD HELP SUPPORT AREAS OF FOG LATE TONIGHT.
THE TEMPERATURE GUIDANCE WAS CONSISTENT.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
DRY WEATHER WILL CONTINUE WEDNESDAY WITH LIMITED MOISTURE ACROSS
THE REGION. A FLAT UPPER-LEVEL RIDGE WILL EXTEND ACROSS THE GULF
COAST STATES EASTWARD TO THE ATLANTIC COAST WITH SURFACE HIGH
PRESSURE RIDGING DOWN THE EAST COAST. SHOULD SEE MOSTLY SUNNY
SKIES WEDNESDAY. PAST FEW MODELS RUNS HAVE AGREED ON HIGH
TEMPERATURES IN THE UPPER 80S TO LOWER 90S AND LOWS IN THE UPPER
60S TO LOWER 70S.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
MODELS ARE IN GOOD AGREEMENT THROUGH THE LONG TERM. COLD FRONT
WILL BE STRETCHED BEGINNING THURSDAY FROM NEW ENGLAND
SOUTHWESTWARD THROUGH THE TN VALLEY AND INTO THE LOWER MS VALLEY.
THE FRONT WILL MARCH EASTWARD THURSDAY AFTERNOON AND REACH THE
FORECAST AREA LATE THURSDAY NIGHT/FRIDAY MORNING. THE FRONT WILL
STRUGGLE TO REACH THE COAST AND STALL ACROSS THE REGION FRIDAY
AFTERNOON AND REMAIN NEARLY STATIONARY THROUGH SUNDAY. BUILDING
HIGH PRESSURE OVER THE SOUTHERN GREAT LAKES WILL PUSH THE FRONTAL
REMAINS OFFSHORE LATE SUNDAY AND SUNDAY NIGHT WITH COOLER AND
DRIER AIR ENTERING THE REGION. WITH THE FRONT ACROSS THE REGION
CHANCES OF SHOWERS AND THUNDERSTORMS WILL ONCE AGAIN RETURN TO THE
FORECAST WITH THE HIGHEST POPS CURRENTLY EXPECTED FOR FRIDAY
THROUGH SATURDAY. TEMPERATURES THROUGH THE LONG TERM WILL BE NEAR
NORMAL THROUGH FRIDAY NIGHT WITH BELOW NORMAL EXPECTED FOR
SATURDAY AND SUNDAY.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
HIGH LOW-LEVEL MOISTURE IS TRAPPED BELOW AN INVERSION. THIS
MOISTURE IS IN THE NORTHEAST FLOW BETWEEN A PRESSURE RIDGE ALONG
THE MOUNTAINS AND LOW PRESSURE OFF THE NORTH CAROLINA AND VIRGINIA
COASTS. THE MODELS DISPLAY THE LOW SHIFTING FARTHER NORTHEASTWARD WITH
MOISTURE BECOMING MORE SHALLOW. THE DECREASE IN MOISTURE WITH SOME
HEATING AND MIXING SHOULD HELP CAUSE IMPROVING CEILINGS. WE USED
THE RAP TIME-HEIGHT DISPLAYS AND GFS LAMP FOR THE TIMING OF
IMPROVING CEILINGS. EXPECT VFR CONDITIONS DEVELOPING THIS
AFTERNOON AND CONTINUING THIS EVENING. NOCTURNAL COOLING WITH LIGHT
WIND AND LINGERING LOW-LEVEL MOISTURE PLUS DRY AIR ALOFT SHOULD
HELP SUPPORT FOG DURING THE EARLY MORNING HOURS WEDNESDAY. MOST
OF THE NAM AND GFS MOS INDICATE IFR CONDITIONS DEVELOPING. HEATING
AND MIXING SHOULD DISSIPATE THE FOG LATER IN THE MORNING. USED THE
GFS LAMP FOR THE TIMING.
.EXTENDED AVIATION OUTLOOK...WIDESPREAD STRATUS AND FOG MAY OCCUR
DURING THE EARLY MORNING HOURS THURSDAY. THUNDERSTORMS ARE POSSIBLE
THURSDAY NIGHT AND FRIDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1049 AM EDT TUE SEP 9 2014
.SYNOPSIS...
A SURFACE LOW OVER EASTERN NORTH CAROLINA WILL SLOWLY MOVE
NORTHEAST AS HIGH PRESSURE CONTINUES TO RIDGE INTO THE CAROLINAS
AND GEORGIA FROM THE NORTH. DRIER AIR WILL FILTER INTO THE REGION
TODAY AND WEDNESDAY. A COLD FRONT WILL MOVE INTO THE AREA THURSDAY
NIGHT AND FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
HIGH LOW-LEVEL MOISTURE IS TRAPPED BELOW AN INVERSION. THIS
MOISTURE IS IN THE NORTHEAST FLOW BETWEEN A PRESSURE RIDGE ALONG
THE MOUNTAINS AND LOW PRESSURE OFF THE NORTH CAROLINA AND VIRGINIA
COASTS. THE MODELS DISPLAY THE LOW SHIFTING FARTHER NORTHEASTWARD WITH
MOISTURE BECOMING MORE SHALLOW IN THE FORECAST AREA. THE DECREASE IN
MOISTURE WITH SOME HEATING AND MIXING SHOULD HELP CAUSE BREAKS IN
THE CLOUDINESS. EXPECT TEMPERATURES WILL WARM INTO THE LOWER 80S
NORTH...AND MIDDLE AND UPPER 80S SOUTH. THE SHOWER CHANCE IS LOW
BECAUSE OF SHALLOW MOISTURE. THE HIGH-RESOLUTION MODELS MAINTAIN
DRY CONDITIONS.
HIGH PRESSURE RIDGING INTO THE FORECAST AREA WILL DOMINATE TONIGHT.
NOCTURNAL COOLING WITH LIGHT WIND AND LINGERING LOW-LEVEL MOISTURE
PLUS DRY AIR ALOFT SHOULD HELP SUPPORT AREAS OF FOG LATE TONIGHT.
THE TEMPERATURE GUIDANCE WAS CONSISTENT.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
DRY WEATHER WILL CONTINUE WEDNESDAY WITH LIMITED MOISTURE ACROSS
THE REGION. A FLAT UPPER-LEVEL RIDGE WILL EXTEND ACROSS THE GULF
COAST STATES EASTWARD TO THE ATLANTIC COAST WITH SURFACE HIGH
PRESSURE RIDGING DOWN THE EAST COAST. SHOULD SEE MOSTLY SUNNY
SKIES WEDNESDAY. PAST FEW MODELS RUNS HAVE AGREED ON HIGH
TEMPERATURES IN THE UPPER 80S TO LOWER 90S AND LOWS IN THE UPPER
60S TO LOWER 70S.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
MODELS ARE IN GOOD AGREEMENT THROUGH THE LONG TERM. COLD FRONT
WILL BE STRETCHED BEGINNING THURSDAY FROM NEW ENGLAND
SOUTHWESTWARD THROUGH THE TN VALLEY AND INTO THE LOWER MS VALLEY.
THE FRONT WILL MARCH EASTWARD THURSDAY AFTERNOON AND REACH THE
FORECAST AREA LATE THURSDAY NIGHT/FRIDAY MORNING. THE FRONT WILL
STRUGGLE TO REACH THE COAST AND STALL ACROSS THE REGION FRIDAY
AFTERNOON AND REMAIN NEARLY STATIONARY THROUGH SUNDAY. BUILDING
HIGH PRESSURE OVER THE SOUTHERN GREAT LAKES WILL PUSH THE FRONTAL
REMAINS OFFSHORE LATE SUNDAY AND SUNDAY NIGHT WITH COOLER AND
DRIER AIR ENTERING THE REGION. WITH THE FRONT ACROSS THE REGION
CHANCES OF SHOWERS AND THUNDERSTORMS WILL ONCE AGAIN RETURN TO THE
FORECAST WITH THE HIGHEST POPS CURRENTLY EXPECTED FOR FRIDAY
THROUGH SATURDAY. TEMPERATURES THROUGH THE LONG TERM WILL BE NEAR
NORMAL THROUGH FRIDAY NIGHT WITH BELOW NORMAL EXPECTED FOR
SATURDAY AND SUNDAY.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
HIGH LOW-LEVEL MOISTURE IS TRAPPED BELOW AN INVERSION. THIS
MOISTURE IS IN THE NORTHEAST FLOW BETWEEN A PRESSURE RIDGE ALONG
THE MOUNTAINS AND LOW PRESSURE OFF THE NORTH CAROLINA AND VIRGINIA
COAST. THE MODELS DISPLAY THE LOW SHIFTING FARTHER NORTHEASTWARD WITH
MOISTURE BECOMING MORE SHALLOW. THE DECREASE IN MOISTURE WITH SOME
HEATING AND MIXING SHOULD HELP CAUSE IMPROVING CEILINGS. WE USED
THE RAP TIME-HEIGHT DISPLAYS AND GFS LAMP FOR THE TIMING OF
IMPROVING CEILINGS. EXPECT VFR CONDITIONS DEVELOPING THIS
AFTERNOON AND CONTINUING THIS EVENING. NOCTURNAL COOLING WITH LIGHT
WIND AND LINGERING LOW-LEVEL MOISTURE PLUS DRY AIR ALOFT SHOULD
HELP SUPPORT FOG DURING THE EARLY MORNING HOURS WEDNESDAY. MOST OF
THE NAM AND GFS MOS INDICATED IFR CONDITIONS DEVELOPING.
.EXTENDED AVIATION OUTLOOK...WIDESPREAD STRATUS AND FOG MAY OCCUR
DURING THE EARLY MORNING HOURS THURSDAY. THUNDERSTORMS ARE POSSIBLE
THURSDAY NIGHT AND FRIDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
812 AM EDT TUE SEP 9 2014
.SYNOPSIS...
A SURFACE LOW OVER EASTERN NORTH CAROLINA WILL SLOWLY MOVE
NORTHEAST AS HIGH PRESSURE CONTINUES TO RIDGE INTO THE CAROLINAS
AND GEORGIA FROM THE NORTH. DRIER AIR WILL FILTER INTO THE REGION
TODAY AND WEDNESDAY. A COLD FRONT WILL MOVE INTO THE AREA THURSDAY
NIGHT AND FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
WEAK LOW PRESSURE WAS LOCATED OVER EASTERN NC THIS MORNING WITH
ITS ASSOCIATED COLD FRONT EXTENDING OFF THE COAST OF SOUTH
CAROLINA AND ACROSS SOUTHERN GEORGIA. THE AREA OF LOW PRESSURE
WILL CONTINUE MOVING NORTHEAST TODAY. HIGH PRESSURE ANCHORED OVER
NEW ENGLAND WILL CONTINUE RIDGING INTO THE CAROLINAS AND GEORGIA
FROM THE NORTH. CLOUDS THIS MORNING WILL DECREASE THIS AFTERNOON
AS THE LOW SHIFTS FARTHER NORTHEAST. ISOLATED CONVECTION IS
POSSIBLE THIS AFTERNOON ACROSS THE EXTREME EASTERN MIDLANDS AND
CSRA WHERE MOISTURE AND INSTABILITY WILL BE HIGHER. AS PER
GUIDANCE...WE WENT WITH POPS LESS THAN 20 PERCENT. EVEN WITH A
LITTLE SUNSHINE...TEMPERATURES SHOULD REACH THE MID TO UPPER 80S.
LIGHT WIND WITH LINGERING LOW-LEVEL MOISTURE AND DRY AIR ALOFT
SHOULD HELP SUPPORT AREAS OF FOG LATE TONIGHT.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
DRY WEATHER WILL CONTINUE WEDNESDAY WITH LIMITED MOISTURE ACROSS
THE REGION. A FLAT UPPER-LEVEL RIDGE WILL EXTEND ACROSS THE GULF
COAST STATES EASTWARD TO THE ATLANTIC COAST WITH SURFACE HIGH
PRESSURE RIDGING DOWN THE EAST COAST. SHOULD SEE MOSTLY SUNNY
SKIES WEDNESDAY. PAST FEW MODELS RUNS HAVE AGREED ON HIGH
TEMPERATURES IN THE UPPER 80S TO LOWER 90S AND LOWS IN THE UPPER
60S TO LOWER 70S.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
MODELS ARE IN GOOD AGREEMENT THROUGH THE LONG TERM. COLD FRONT
WILL BE STRETCHED BEGINNING THURSDAY FROM NEW ENGLAND
SOUTHWESTWARD THROUGH THE TN VALLEY AND INTO THE LOWER MS VALLEY.
THE FRONT WILL MARCH EASTWARD THURSDAY AFTERNOON AND REACH THE
FORECAST AREA LATE THURSDAY NIGHT/FRIDAY MORNING. THE FRONT WILL
STRUGGLE TO REACH THE COAST AND STALL ACROSS THE REGION FRIDAY
AFTERNOON AND REMAIN NEARLY STATIONARY THROUGH SUNDAY. BUILDING
HIGH PRESSURE OVER THE SOUTHERN GREAT LAKES WILL PUSH THE FRONTAL
REMAINS OFFSHORE LATE SUNDAY AND SUNDAY NIGHT WITH COOLER AND
DRIER AIR ENTERING THE REGION. WITH THE FRONT ACROSS THE REGION
CHANCES OF SHOWERS AND THUNDERSTORMS WILL ONCE AGAIN RETURN TO THE
FORECAST WITH THE HIGHEST POPS CURRENTLY EXPECTED FOR FRIDAY
THROUGH SATURDAY. TEMPERATURES THROUGH THE LONG TERM WILL BE NEAR
NORMAL THROUGH FRIDAY NIGHT WITH BELOW NORMAL EXPECTED FOR
SATURDAY AND SUNDAY.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
FRONT HAS MOVED EAST OF THE AREA WITH HIGH PRESSURE BUILDING SOUTH
FROM NORTH CAROLINA ACROSS THE AREA. THIS IS RESULTING IN NORTH TO
NORTHEAST LOW-LEVEL FLOW AND WIDESPREAD LOW CLOUDINESS ACROSS THE
REGION. WE USED THE RAP TIME-HEIGHT DISPLAYS AND GFS LAMP FOR THE
TIMING OF IMPROVING CEILINGS. EXPECT VFR CONDITIONS THIS AFTERNOON
AND EVENING. LIGHT WIND WITH LINGERING LOW-LEVEL MOISTURE AND DRY
AIR ALOFT SHOULD HELP SUPPORT FOG DURING THE EARLY MORNING HOURS
WEDNESDAY. MOST OF THE NAM AND GFS MOS SUPPORT IFR CONDITIONS
DEVELOPING.
.EXTENDED AVIATION OUTLOOK...WIDESPREAD STRATUS AND FOG MAY OCCUR
DURING THE EARLY MORNING HOURS THURSDAY. THUNDERSTORMS ARE POSSIBLE
THURSDAY NIGHT AND FRIDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
755 AM EDT TUE SEP 9 2014
.SYNOPSIS...
A SURFACE LOW OVER EASTERN NORTH CAROLINA WILL SLOWLY MOVE
NORTHEAST AS HIGH PRESSURE CONTINUES TO RIDGE INTO THE CAROLINAS
AND GEORGIA FROM THE NORTH. DRIER AIR WILL FILTER INTO THE REGION
TODAY AND WEDNESDAY. A COLD FRONT WILL MOVE INTO THE AREA THURSDAY
NIGHT AND FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
WEAK LOW PRESSURE WAS LOCATED OVER EASTERN NC THIS MORNING WITH
ITS ASSOCIATED COLD FRONT EXTENDING OFF THE COAST OF SOUTH
CAROLINA AND ACROSS SOUTHERN GEORGIA. THE AREA OF LOW PRESSURE
WILL CONTINUE MOVING NORTHEAST TODAY. HIGH PRESSURE ANCHORED OVER
NEW ENGLAND WILL CONTINUE RIDGING INTO THE CAROLINAS AND GEORGIA
FROM THE NORTH. CLOUDS THIS MORNING WILL DECREASE THIS AFTERNOON
AS THE LOW SHIFTS FARTHER NORTHEAST. ISOLATED CONVECTION IS
POSSIBLE THIS AFTERNOON ACROSS THE EXTREME EASTERN MIDLANDS AND
CSRA WHERE MOISTURE AND INSTABILITY WILL BE HIGHER. AS PER
GUIDANCE...WE WENT WITH POPS LESS THAN 20 PERCENT. EVEN WITH A
LITTLE SUNSHINE...TEMPERATURES SHOULD REACH THE MID TO UPPER 80S.
LIGHT WIND WITH LINGERING LOW-LEVEL MOISTURE AND DRY AIR ALOFT
SHOULD HELP SUPPORT AREAS OF FOG LATE TONIGHT.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
DRY WEATHER WILL CONTINUE WEDNESDAY WITH LIMITED MOISTURE ACROSS
THE REGION. A FLAT UPPER-LEVEL RIDGE WILL EXTEND ACROSS THE GULF
COAST STATES EASTWARD TO THE ATLANTIC COAST WITH SURFACE HIGH
PRESSURE RIDGING DOWN THE EAST COAST. SHOULD SEE MOSTLY SUNNY
SKIES WEDNESDAY. PAST FEW MODELS RUNS HAVE AGREED ON HIGH
TEMPERATURES IN THE UPPER 80S TO LOWER 90S AND LOWS IN THE UPPER
60S TO LOWER 70S.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
MODELS ARE IN GOOD AGREEMENT THROUGH THE LONG TERM. COLD FRONT
WILL BE STRETCHED BEGINNING THURSDAY FROM NEW ENGLAND
SOUTHWESTWARD THROUGH THE TN VALLEY AND INTO THE LOWER MS VALLEY.
THE FRONT WILL MARCH EASTWARD THURSDAY AFTERNOON AND REACH THE
FORECAST AREA LATE THURSDAY NIGHT/FRIDAY MORNING. THE FRONT WILL
STRUGGLE TO REACH THE COAST AND STALL ACROSS THE REGION FRIDAY
AFTERNOON AND REMAIN NEARLY STATIONARY THROUGH SUNDAY. BUILDING
HIGH PRESSURE OVER THE SOUTHERN GREAT LAKES WILL PUSH THE FRONTAL
REMAINS OFFSHORE LATE SUNDAY AND SUNDAY NIGHT WITH COOLER AND
DRIER AIR ENTERING THE REGION. WITH THE FRONT ACROSS THE REGION
CHANCES OF SHOWERS AND THUNDERSTORMS WILL ONCE AGAIN RETURN TO THE
FORECAST WITH THE HIGHEST POPS CURRENTLY EXPECTED FOR FRIDAY
THROUGH SATURDAY. TEMPERATURES THROUGH THE LONG TERM WILL BE NEAR
NORMAL THROUGH FRIDAY NIGHT WITH BELOW NORMAL EXPECTED FOR
SATURDAY AND SUNDAY.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
FRONT HAS MOVED EAST OF THE AREA WITH HIGH PRESSURE BUILDING SOUTH
FROM NORTH CAROLINA ACROSS THE AREA. THIS IS RESULTING IN NORTH TO
NORTHEAST LOW-LEVEL FLOW AND WIDESPREAD LOW CLOUDINESS ACROSS THE
REGION. WE USED THE RAP TIME-HEIGHT DISPLAYS AND GFS LAMP FOR THE
TIMING OF IMPROVING CEILINGS. EXPECT VFR CONDITIONS THIS AFTERNOON
AND EVENING. LIGHT WIND WITH LINGERING LOW-LEVEL MOISTURE AND DRY
AIR ALOFT SHOULD HELP SUPPORT FOG DURING THE EARLY MORNING HOURS
WEDNESDAY. MOST OF THE NAM AND GFS MOS SUPPORT IFR CONDITIONS
DEVELOPING.
.EXTENDED AVIATION OUTLOOK...SHOWERS AND THUNDERSTORMS ARE POSSIBLE
THURSDAY NIGHT AND FRIDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1249 PM EDT TUE SEP 9 2014
.SYNOPSIS...
ISSUED AT 1245 AM EDT TUE SEP 9 2014
AN AREA OF LOW PRESSURE WILL BEGIN ORGANIZING IN THE PLAINS THIS AFTERNOON AND
WILL STRENGTHEN CONSIDERABLY TONIGHT AS IT MOVES INTO THE UPPER
MISSISSIPPI VALLEY BY WEDNESDAY MORNING. MOSTLY CLOUDY SKIES WILL
BECOME MOSTLY SUNNY BY LAT THIS AFTERNOON. HIGH TEMPERATURES
SHOULD CLIMB INTO THE UPPER 70S ACROSS THE REGION. THERE IS A
CHANCE FOR SHOWERS AND THUNDERSTORMS LATE ACROSS NORTHEAST
ILLINOIS...NORTHWEST INDIANA AND SOUTHWEST LOWER MICHIGAN. LOW
TEMPERATURES WILL ONLY DROP INTO THE 60S AND IT WILL FEEL MORE
HUMID OVERNIGHT AS WELL. BETTER CHANCES FOR THUNDERSTORMS AND
HEAVY RAIN...ALONG WITH A RISK FOR SEVERE STORMS...ARRIVE TOMORROW
INTO WEDNESDAY EVENING ALONG A STRONG COLD FRONT.
&&
.UPDATE...
ISSUED AT 538 AM EDT TUE SEP 9 2014
PRECIPITATION ACROSS IL CONTINUES TO EXPAND EAST ALONG THETA E
SURGE...ALBEIT PCPN APPEARS TO BE LIGHT ON EASTERN FLANK. GETTING
TOO CLOSE FOR COMFORT AND 07Z HRRR NOW BRINGS SOME LIGHT QPF INTO
FAR WESTERN COUNTIES EARLY THIS MORNING. MOST OTHER HIRES GUIDANCE
STILL DEPICTS NO PCPN INTO OUR AREA BUT RADAR/SAT TRENDS SUGGEST A
LOW POP IS PRUDENT THIS MORNING ALONG WITH AN INCREASE IN CLOUD
COVER.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 354 AM EDT TUE SEP 9 2014
THIS SHORT TERM PERIOD REMAINS QUIET BUT EXPECT INCREASING
MOISTURE DURING THE PERIOD AHEAD OF POTENT SHORT WAVE AND SURFACE
COLD FRONT APPROACHING FOR WEDNESDAY.
INITIAL THETA E SURGE RESPONSIBLE FOR CONVECTIVE DEVELOPMENT EARLY
THIS MORNING UPSTREAM ACROSS EASTERN IA AND NORTHWEST IL. RADAR
MOSAIC SHOWS THIS PCPN STRUGGLING TO MOVE EAST INTO DRIER AIR AND
MOST HIRES MODEL GUIDANCE KEEPS PCPN WEST OF OUR AREA TODAY. WILL
THEREFORE KEEP A DRY FORECAST INTACT TODAY BUT WILL SEE INITIAL
SURGE OF HIGHER THETA E AIR WORK EAST DURING THE DAY. MID AND HIGH
CLOUD COVER FROM UPSTREAM CONVECTION WILL PERSIST THIS MORNING AND
WILL LIKELY BE THIN AT TIMES DURING THE DAY. FILTERED SUNSHINE
EXPECTED. CLOUDS TO OFFSET WARMER 925-850MB TEMPS SO HIGHS TODAY
EXPECTED NEAR OR JUST ABOVE MONDAY TEMPS.
STRONG CYCLOGENESIS OCCURS TONIGHT IN THE PLAINS WITH POTENT SHORT
WAVE AND STRONG UPPER LEVEL JET DYNAMICS. SECONDARY THETA E SURGE
WILL APPROACH LATE TONIGHT BUT MAIN FORCING EXPECTED TO REMAIN WEST
OF OUR AREA UNTIL WEDNESDAY. ISENTROPIC UPGLIDE IS DEPICTED ON
MODELS WITH SOME SATURATION BUT EXPECT THIS TO GO MORE INTO CLOUD
FORMATION AND MOISTENING OF ATMOSPHERE. THETA E GRADIENT DOES ENTER
NORTHWEST AREAS LATE SO WILL KEEP A LOW CHANCE THERE LATE TONIGHT.
WITH INCREASING CLOUDS...GRADIENT AND MOISTURE EXPECT LOW TEMPS TO
REMAIN IN THE 60S. HAVE USED A WARMER BLEND OF GUIDANCE FOR LOWS.
&&
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 354 AM EDT TUE SEP 9 2014
ALL EYES ON WEDNESDAY`S SYSTEM WITH CHILLY TEMPS BEING THE ONLY
SENSIBLE WEATHER CONCERN FOR THE REST OF THE PERIOD. SHORTWAVE
TROUGH CURRENTLY OVER NORTHERN CALIFORNIA STILL EXPECTED TO EJECT
INTO THE CENTRAL PLAINS AND BECOME NEGATIVELY TILTED AS IT CROSSES
THE GREAT LAKES ON WEDNESDAY. AMPLIFYING LONGWAVE PATTERN WILL
SUPPORT A TIGHTENING BAROCLINIC ZONE ACROSS THE REGION AND COUPLED
UPPER LEVEL JET STREAKS WILL FAVOR STRONG CYCLOGENESIS ALONG THIS
BOUNDARY. SYNOPTIC SCALE DETAILS REMAIN CONSISTENT IN LATEST MODEL
SUITE. BEST PV ADVECTION AND DEFORMATION FORCING WILL PASS TO OUR
NORTHWEST CLOSER TO THE SURFACE LOW TRACK BUT GOOD MIDLEVEL HEIGHT
FALLS AND ASSOCIATED LOW LEVEL CONVERGENCE WILL STILL LEAD TO GOOD
FGEN ALONG TRAILING COLD FRONT. AS HAS BEEN DISCUSSED FOR SEVERAL
DAYS...THIS SYSTEM WILL HAVE AMPLE MOISTURE TO WORK WITH. DEEP
MONSOONAL MOISTURE CURRENTLY OVER THE SOUTHWEST CONUS WILL BE DRAWN
NORTH WITH THIS WAVE...ALONG WITH MOISTURE ADVECTION FROM THE
WESTERN GULF/SOUTHERN PLAINS. PW VALUES STILL EXPECTED TO BE OVER 2
INCHES...RECORD TERRITORY FOR THE MONTH OF SEPTEMBER. THIS COUPLED
WITH GOOD FORCING FOR ASCENT ALONG AND AHEAD OF THE FRONT WILL
SUPPORT WIDESPREAD RAIN ON WEDNESDAY. TWO POSSIBLE IMPACTS TO
DISCUSS...SEVERE WEATHER AND HEAVY RAIN.
SEVERE WEATHER POTENTIAL WILL BE ENTIRELY DEPENDENT ON DEGREE OF
DIABATIC BOUNDARY LAYER HEATING EARLY IN THE DAY. 00Z NAM STILL A
RELATIVE OUTLIER IN SUGGESTING SBCAPE VALUES OF AROUND 2000
J/KG...PERPLEXING GIVEN THE DEGREE OF MORNING CLOUD COVER SEEN IN RH
FIELDS AND FORECAST SOUNDINGS. STILL PREFER THE MORE SUBDUED GFS
INSTABILITY VALUES GIVEN FAIRLY CONSISTENT RH/CLOUD FORECASTS SEEN
IN ALL OF THE MODELS. THAT BEING SAID...A SIGNIFICANT SEVERE WEATHER
OUTBREAK WILL BE POSSIBLE IF WE MANAGE TO GET ENOUGH SURFACE HEATING
BEFORE THE FRONT ARRIVES. KINEMATICS ARE EXCELLENT WITH 850MB WINDS
AT OR ABOVE 50 KTS AND GOOD DEEP LAYER SHEAR AS WELL. PRECIP LOADING
IN VERY MOIST ENVIRONMENT WILL HAVE LITTLE TROUBLE BRINGING STRONG
WIND CORE DOWN TO THE SURFACE WITH EVEN LIMITED INSTABILITY.
ISOLATED TORNADOES WILL ALSO BE A THREAT GIVEN LOW LCL`S AND STRONG
SHEAR. WHILE CURRENT EXPECTATIONS ARE FOR MORNING CLOUDS TO CURTAIL
THE SEVERE RISK SOMEWHAT...CONFIDENCE IN THIS SCENARIO IS NOT HIGH
AND EVERYONE SHOULD CONTINUE TO MONITOR THE LATEST FORECASTS CLOSELY
AS IT DOES NOT TAKE A LOT OF INSTABILITY TO GENERATE SIGNIFICANT
SEVERE WEATHER IN THESE HIGH SHEAR SITUATIONS. SUBTLE BOUNDARY LAYER
HEATING WILL MAKE THE DIFFERENCE BETWEEN A SIGNIFICANT OUTBREAK AND
A NONEVENT AND THAT IS DIFFICULT TO PINPOINT THIS FAR IN ADVANCE.
SOUTHEAST PORTIONS OF OUR CWA APPEAR TO HAVE THE BEST CHANCES FOR
SEVERE WEATHER AT THIS POINT...GIVEN FURTHER DISPLACEMENT FROM
MORNING PRECIP AND CLOUD DEBRIS.
THE OTHER IMPACT WILL BE POTENTIAL FOR HEAVY RAIN AND LOCALIZED
FLOODING. AGAIN...THIS WILL DEPEND SOMEWHAT ON DEGREE OF DIURNAL
DESTABILIZATION BUT EXPECT SOME HEALTHY RAINFALL AMOUNTS REGARDLESS
OF CONVECTIVE COMPONENT. AS PREVIOUSLY MENTIONED...TROPOSPHERIC
MOISTURE WILL BE UNUSUALLY HIGH. FORECAST SOUNDINGS SHOW A WARM
CLOUD LAYER OF AROUND 13 KFT...FAVORING EFFICIENT
COLLISION/COALESCENCE PROCESSES. MEAN FLOW VECTORS ARE ORIENTED A
BIT TOO ORTHOGONAL TO THE FRONT FOR A VERY LONG DURATION OF HEAVY
RAIN BUT SOME TRAINING WILL BE POSSIBLE. THIS WILL LEAD TO SOME
LOCALLY HEAVY RAIN GIVEN AVAILABLE MOISTURE AND PRECIP EFFICIENCY.
EXPECT MOST AREAS WILL SEE AROUND AN INCH WITH ISOLATED POCKETS OF
HIGHER AMOUNTS POSSIBLE.
MAINLY DRY CONDITIONS EXPECTED AFTER TOMORROW. A SECONDARY VORT MAX
WILL SWING THROUGH THE GREAT LAKES ON FRIDAY NIGHT AND MAY GENERATE
A FEW RAIN SHOWERS. MAIN STORY WILL BE MUCH COOLER CONDITIONS. 850MB
TEMPS EXPECTED TO DROP TO NEAR 0C BY THIS WEEKEND. ALSO EXPECTING A
HEALTHY CU/STRATOCU DECK ON THURSDAY AND FRIDAY TO KEEP A LID ON
AFTERNOON TEMPS. THIS SHOULD LEAD TO HIGH TEMPS IN THE LOW TO MID
60S THROUGH SUNDAY WITH OVERNIGHT LOWS IN THE LOW TO MID 40S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1226 PM EDT TUE SEP 9 2014
SHOWERS WITH MCV HAVE BASICALLY EVAPORATED IN DRY AIRMASS LEAVING
DRY/VFR CONDITIONS INTO THIS EVENING AS LARGE SCALE
SUBSIDENCE/DRYING BRIEFLY MOVES THROUGH. CHANCES FOR ELEVATED
CONVECTION/RESTRICTIONS AND INCREASING SOUTH-SOUTHEAST FLOW/SHEAR
WILL INCREASE AT MAINLY SBN LATER TONIGHT/TOMORROW IN RESPONSE TO
PRIMARY THETA-E SURGE ASSOCIATED WITH IA/SW WI CYCLOGENESIS.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
UPDATE...LASHLEY
SYNOPSIS...LASHLEY/BENTLEY
SHORT TERM...LASHLEY LONG TERM...AGD
AVIATION...STEINWEDEL
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...CORRECTION
NWS NORTHERN INDIANA
1236 PM EDT TUE SEP 9 2014
.SYNOPSIS...
ISSUED AT 354 AM EDT TUE SEP 9 2014
AN AREA OF LOW PRESSURE WILL BEGIN ORGANIZING IN THE PLAINS TODAY
AND WILL STRENGTHEN CONSIDERABLY TONIGHT AS IT MOVES INTO THE
UPPER MISSISSIPPI VALLEY BY WEDNESDAY MORNING. MID AND UPPER LEVEL
CLOUDS WILL BE ACROSS OUR AREA TODAY. HIGH TEMPERATURES SHOULD
CLIMB INTO THE UPPER 70S ACROSS THE REGION. THERE IS A CHANCE FOR
SHOWERS AND THUNDERSTORMS LATE ACROSS NORTHEAST ILLINOIS...NORTHWEST
INDIANA AND SOUTHWEST LOWER MICHIGAN. LOW TEMPERATURES WILL ONLY
DROP INTO THE 60S AND IT WILL FEEL MORE HUMID OVERNIGHT AS WELL.
BETTER CHANCES FOR THUNDERSTORMS AND HEAVY RAIN...ALONG WITH A
RISK FOR SEVERE STORMS...ARRIVE TOMORROW INTO WEDNESDAY EVENING
ALONG A STRONG COLD FRONT.
&&
.UPDATE...
ISSUED AT 538 AM EDT TUE SEP 9 2014
PRECIPITATION ACROSS IL CONTINUES TO EXPAND EAST ALONG THETA E
SURGE...ALBEIT PCPN APPEARS TO BE LIGHT ON EASTERN FLANK. GETTING
TOO CLOSE FOR COMFORT AND 07Z HRRR NOW BRINGS SOME LIGHT QPF INTO
FAR WESTERN COUNTIES EARLY THIS MORNING. MOST OTHER HIRES GUIDANCE
STILL DEPICTS NO PCPN INTO OUR AREA BUT RADAR/SAT TRENDS SUGGEST A
LOW POP IS PRUDENT THIS MORNING ALONG WITH AN INCREASE IN CLOUD
COVER.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 354 AM EDT TUE SEP 9 2014
THIS SHORT TERM PERIOD REMAINS QUIET BUT EXPECT INCREASING
MOISTURE DURING THE PERIOD AHEAD OF POTENT SHORT WAVE AND SURFACE
COLD FRONT APPROACHING FOR WEDNESDAY.
INITIAL THETA E SURGE RESPONSIBLE FOR CONVECTIVE DEVELOPMENT EARLY
THIS MORNING UPSTREAM ACROSS EASTERN IA AND NORTHWEST IL. RADAR
MOSAIC SHOWS THIS PCPN STRUGGLING TO MOVE EAST INTO DRIER AIR AND
MOST HIRES MODEL GUIDANCE KEEPS PCPN WEST OF OUR AREA TODAY. WILL
THEREFORE KEEP A DRY FORECAST INTACT TODAY BUT WILL SEE INITIAL
SURGE OF HIGHER THETA E AIR WORK EAST DURING THE DAY. MID AND HIGH
CLOUD COVER FROM UPSTREAM CONVECTION WILL PERSIST THIS MORNING AND
WILL LIKELY BE THIN AT TIMES DURING THE DAY. FILTERED SUNSHINE
EXPECTED. CLOUDS TO OFFSET WARMER 925-850MB TEMPS SO HIGHS TODAY
EXPECTED NEAR OR JUST ABOVE MONDAY TEMPS.
STRONG CYCLOGENESIS OCCURS TONIGHT IN THE PLAINS WITH POTENT SHORT
WAVE AND STRONG UPPER LEVEL JET DYNAMICS. SECONDARY THETA E SURGE
WILL APPROACH LATE TONIGHT BUT MAIN FORCING EXPECTED TO REMAIN WEST
OF OUR AREA UNTIL WEDNESDAY. ISENTROPIC UPGLIDE IS DEPICTED ON
MODELS WITH SOME SATURATION BUT EXPECT THIS TO GO MORE INTO CLOUD
FORMATION AND MOISTENING OF ATMOSPHERE. THETA E GRADIENT DOES ENTER
NORTHWEST AREAS LATE SO WILL KEEP A LOW CHANCE THERE LATE TONIGHT.
WITH INCREASING CLOUDS...GRADIENT AND MOISTURE EXPECT LOW TEMPS TO
REMAIN IN THE 60S. HAVE USED A WARMER BLEND OF GUIDANCE FOR LOWS.
&&
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 354 AM EDT TUE SEP 9 2014
ALL EYES ON WEDNESDAY`S SYSTEM WITH CHILLY TEMPS BEING THE ONLY
SENSIBLE WEATHER CONCERN FOR THE REST OF THE PERIOD. SHORTWAVE
TROUGH CURRENTLY OVER NORTHERN CALIFORNIA STILL EXPECTED TO EJECT
INTO THE CENTRAL PLAINS AND BECOME NEGATIVELY TILTED AS IT CROSSES
THE GREAT LAKES ON WEDNESDAY. AMPLIFYING LONGWAVE PATTERN WILL
SUPPORT A TIGHTENING BAROCLINIC ZONE ACROSS THE REGION AND COUPLED
UPPER LEVEL JET STREAKS WILL FAVOR STRONG CYCLOGENESIS ALONG THIS
BOUNDARY. SYNOPTIC SCALE DETAILS REMAIN CONSISTENT IN LATEST MODEL
SUITE. BEST PV ADVECTION AND DEFORMATION FORCING WILL PASS TO OUR
NORTHWEST CLOSER TO THE SURFACE LOW TRACK BUT GOOD MIDLEVEL HEIGHT
FALLS AND ASSOCIATED LOW LEVEL CONVERGENCE WILL STILL LEAD TO GOOD
FGEN ALONG TRAILING COLD FRONT. AS HAS BEEN DISCUSSED FOR SEVERAL
DAYS...THIS SYSTEM WILL HAVE AMPLE MOISTURE TO WORK WITH. DEEP
MONSOONAL MOISTURE CURRENTLY OVER THE SOUTHWEST CONUS WILL BE DRAWN
NORTH WITH THIS WAVE...ALONG WITH MOISTURE ADVECTION FROM THE
WESTERN GULF/SOUTHERN PLAINS. PW VALUES STILL EXPECTED TO BE OVER 2
INCHES...RECORD TERRITORY FOR THE MONTH OF SEPTEMBER. THIS COUPLED
WITH GOOD FORCING FOR ASCENT ALONG AND AHEAD OF THE FRONT WILL
SUPPORT WIDESPREAD RAIN ON WEDNESDAY. TWO POSSIBLE IMPACTS TO
DISCUSS...SEVERE WEATHER AND HEAVY RAIN.
SEVERE WEATHER POTENTIAL WILL BE ENTIRELY DEPENDENT ON DEGREE OF
DIABATIC BOUNDARY LAYER HEATING EARLY IN THE DAY. 00Z NAM STILL A
RELATIVE OUTLIER IN SUGGESTING SBCAPE VALUES OF AROUND 2000
J/KG...PERPLEXING GIVEN THE DEGREE OF MORNING CLOUD COVER SEEN IN RH
FIELDS AND FORECAST SOUNDINGS. STILL PREFER THE MORE SUBDUED GFS
INSTABILITY VALUES GIVEN FAIRLY CONSISTENT RH/CLOUD FORECASTS SEEN
IN ALL OF THE MODELS. THAT BEING SAID...A SIGNIFICANT SEVERE WEATHER
OUTBREAK WILL BE POSSIBLE IF WE MANAGE TO GET ENOUGH SURFACE HEATING
BEFORE THE FRONT ARRIVES. KINEMATICS ARE EXCELLENT WITH 850MB WINDS
AT OR ABOVE 50 KTS AND GOOD DEEP LAYER SHEAR AS WELL. PRECIP LOADING
IN VERY MOIST ENVIRONMENT WILL HAVE LITTLE TROUBLE BRINGING STRONG
WIND CORE DOWN TO THE SURFACE WITH EVEN LIMITED INSTABILITY.
ISOLATED TORNADOES WILL ALSO BE A THREAT GIVEN LOW LCL`S AND STRONG
SHEAR. WHILE CURRENT EXPECTATIONS ARE FOR MORNING CLOUDS TO CURTAIL
THE SEVERE RISK SOMEWHAT...CONFIDENCE IN THIS SCENARIO IS NOT HIGH
AND EVERYONE SHOULD CONTINUE TO MONITOR THE LATEST FORECASTS CLOSELY
AS IT DOES NOT TAKE A LOT OF INSTABILITY TO GENERATE SIGNIFICANT
SEVERE WEATHER IN THESE HIGH SHEAR SITUATIONS. SUBTLE BOUNDARY LAYER
HEATING WILL MAKE THE DIFFERENCE BETWEEN A SIGNIFICANT OUTBREAK AND
A NONEVENT AND THAT IS DIFFICULT TO PINPOINT THIS FAR IN ADVANCE.
SOUTHEAST PORTIONS OF OUR CWA APPEAR TO HAVE THE BEST CHANCES FOR
SEVERE WEATHER AT THIS POINT...GIVEN FURTHER DISPLACEMENT FROM
MORNING PRECIP AND CLOUD DEBRIS.
THE OTHER IMPACT WILL BE POTENTIAL FOR HEAVY RAIN AND LOCALIZED
FLOODING. AGAIN...THIS WILL DEPEND SOMEWHAT ON DEGREE OF DIURNAL
DESTABILIZATION BUT EXPECT SOME HEALTHY RAINFALL AMOUNTS REGARDLESS
OF CONVECTIVE COMPONENT. AS PREVIOUSLY MENTIONED...TROPOSPHERIC
MOISTURE WILL BE UNUSUALLY HIGH. FORECAST SOUNDINGS SHOW A WARM
CLOUD LAYER OF AROUND 13 KFT...FAVORING EFFICIENT
COLLISION/COALESCENCE PROCESSES. MEAN FLOW VECTORS ARE ORIENTED A
BIT TOO ORTHOGONAL TO THE FRONT FOR A VERY LONG DURATION OF HEAVY
RAIN BUT SOME TRAINING WILL BE POSSIBLE. THIS WILL LEAD TO SOME
LOCALLY HEAVY RAIN GIVEN AVAILABLE MOISTURE AND PRECIP EFFICIENCY.
EXPECT MOST AREAS WILL SEE AROUND AN INCH WITH ISOLATED POCKETS OF
HIGHER AMOUNTS POSSIBLE.
MAINLY DRY CONDITIONS EXPECTED AFTER TOMORROW. A SECONDARY VORT MAX
WILL SWING THROUGH THE GREAT LAKES ON FRIDAY NIGHT AND MAY GENERATE
A FEW RAIN SHOWERS. MAIN STORY WILL BE MUCH COOLER CONDITIONS. 850MB
TEMPS EXPECTED TO DROP TO NEAR 0C BY THIS WEEKEND. ALSO EXPECTING A
HEALTHY CU/STRATOCU DECK ON THURSDAY AND FRIDAY TO KEEP A LID ON
AFTERNOON TEMPS. THIS SHOULD LEAD TO HIGH TEMPS IN THE LOW TO MID
60S THROUGH SUNDAY WITH OVERNIGHT LOWS IN THE LOW TO MID 40S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1226 PM EDT TUE SEP 9 2014
SHOWERS WITH MCV HAVE BASICALLY EVAPORATED IN DRY AIRMASS LEAVING
DRY/VFR CONDITIONS INTO THIS EVENING AS LARGE SCALE
SUBSIDENCE/DRYING BRIEFLY MOVES THROUGH. CHANCES FOR ELEVATED
CONVECTION/RESTRICTIONS AND INCREASING SOUTH-SOUTHEAST FLOW/SHEAR
WILL INCREASE AT MAINLY SBN LATER TONIGHT/TOMORROW IN RESPONSE TO
PRIMARY THETA-E SURGE ASSOCIATED WITH IA/SW WI CYCLOGENESIS.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
UPDATE...LASHLEY
SYNOPSIS...LASHLEY
SHORT TERM...LASHLEY
LONG TERM...AGD
AVIATION...STEINWEDEL
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
641 AM EDT TUE SEP 9 2014
.SYNOPSIS...
ISSUED AT 354 AM EDT TUE SEP 9 2014
AN AREA OF LOW PRESSURE WILL BEGIN ORGANIZING IN THE PLAINS TODAY
AND WILL STRENGTHEN CONSIDERABLY TONIGHT AS IT MOVES INTO THE
UPPER MISSISSIPPI VALLEY BY WEDNESDAY MORNING. MID AND UPPER LEVEL
CLOUDS WILL BE ACROSS OUR AREA TODAY. THERE IS A SMALL CHANCE FOR
SHOWERS IN THE FAR WEST THIS MORNING. HIGH TEMPERATURES SHOULD
CLIMB TO NEAR 80 ACROSS THE REGION. SKIES WILL BECOME MOSTLY
CLOUDY TONIGHT. THERE IS A CHANCE FOR SHOWERS AND THUNDERSTORMS
LATE ACROSS NORTHEAST ILLINOIS...NORTHWEST INDIANA AND SOUTHWEST
LOWER MICHIGAN. LOW TEMPERATURES WILL ONLY DROP INTO THE 60S AND
IT WILL FEEL MORE HUMID OVERNIGHT AS WELL.
&&
.UPDATE...
ISSUED AT 538 AM EDT TUE SEP 9 2014
PRECIPITATION ACROSS IL CONTINUES TO EXPAND EAST ALONG THETA E SURGE...ALBEIT
PCPN APPEARS TO BE LIGHT ON EASTERN FLANK. GETTING TOO CLOSE FOR
COMFORT AND 07Z HRRR NOW BRINGS SOME LIGHT QPF INTO FAR WESTERN
COUNTIES EARLY THIS MORNING. MOST OTHER HIRES GUIDANCE STILL
DEPICTS NO PCPN INTO OUR AREA BUT RADAR/SAT TRENDS SUGGEST A LOW
POP IS PRUDENT THIS MORNING ALONG WITH AN INCREASE IN CLOUD COVER.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 354 AM EDT TUE SEP 9 2014
THIS SHORT TERM PERIOD REMAINS QUIET BUT EXPECT INCREASING
MOISTURE DURING THE PERIOD AHEAD OF POTENT SHORT WAVE AND SURFACE
COLD FRONT APPROACHING FOR WEDNESDAY.
INITIAL THETA E SURGE RESPONSIBLE FOR CONVECTIVE DEVELOPMENT EARLY
THIS MORNING UPSTREAM ACROSS EASTERN IA AND NORTHWEST IL. RADAR
MOSAIC SHOWS THIS PCPN STRUGGLING TO MOVE EAST INTO DRIER AIR AND
MOST HIRES MODEL GUIDANCE KEEPS PCPN WEST OF OUR AREA TODAY. WILL
THEREFORE KEEP A DRY FORECAST INTACT TODAY BUT WILL SEE INITIAL
SURGE OF HIGHER THETA E AIR WORK EAST DURING THE DAY. MID AND HIGH
CLOUD COVER FROM UPSTREAM CONVECTION WILL PERSIST THIS MORNING AND
WILL LIKELY BE THIN AT TIMES DURING THE DAY. FILTERED SUNSHINE
EXPECTED. CLOUDS TO OFFSET WARMER 925-850MB TEMPS SO HIGHS TODAY
EXPECTED NEAR OR JUST ABOVE MONDAY TEMPS.
STRONG CYCLOGENESIS OCCURS TONIGHT IN THE PLAINS WITH POTENT SHORT
WAVE AND STRONG UPPER LEVEL JET DYNAMICS. SECONDARY THETA E SURGE
WILL APPROACH LATE TONIGHT BUT MAIN FORCING EXPECTED TO REMAIN WEST
OF OUR AREA UNTIL WEDNESDAY. ISENTROPIC UPGLIDE IS DEPICTED ON
MODELS WITH SOME SATURATION BUT EXPECT THIS TO GO MORE INTO CLOUD
FORMATION AND MOISTENING OF ATMOSPHERE. THETA E GRADIENT DOES ENTER
NORTHWEST AREAS LATE SO WILL KEEP A LOW CHANCE THERE LATE TONIGHT.
WITH INCREASING CLOUDS...GRADIENT AND MOISTURE EXPECT LOW TEMPS TO
REMAIN IN THE 60S. HAVE USED A WARMER BLEND OF GUIDANCE FOR LOWS.
&&
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 354 AM EDT TUE SEP 9 2014
ALL EYES ON WEDNESDAY`S SYSTEM WITH CHILLY TEMPS BEING THE ONLY
SENSIBLE WEATHER CONCERN FOR THE REST OF THE PERIOD. SHORTWAVE
TROUGH CURRENTLY OVER NORTHERN CALIFORNIA STILL EXPECTED TO EJECT
INTO THE CENTRAL PLAINS AND BECOME NEGATIVELY TILTED AS IT CROSSES
THE GREAT LAKES ON WEDNESDAY. AMPLIFYING LONGWAVE PATTERN WILL
SUPPORT A TIGHTENING BAROCLINIC ZONE ACROSS THE REGION AND COUPLED
UPPER LEVEL JET STREAKS WILL FAVOR STRONG CYCLOGENESIS ALONG THIS
BOUNDARY. SYNOPTIC SCALE DETAILS REMAIN CONSISTENT IN LATEST MODEL
SUITE. BEST PV ADVECTION AND DEFORMATION FORCING WILL PASS TO OUR
NORTHWEST CLOSER TO THE SURFACE LOW TRACK BUT GOOD MIDLEVEL HEIGHT
FALLS AND ASSOCIATED LOW LEVEL CONVERGENCE WILL STILL LEAD TO GOOD
FGEN ALONG TRAILING COLD FRONT. AS HAS BEEN DISCUSSED FOR SEVERAL
DAYS...THIS SYSTEM WILL HAVE AMPLE MOISTURE TO WORK WITH. DEEP
MONSOONAL MOISTURE CURRENTLY OVER THE SOUTHWEST CONUS WILL BE DRAWN
NORTH WITH THIS WAVE...ALONG WITH MOISTURE ADVECTION FROM THE
WESTERN GULF/SOUTHERN PLAINS. PW VALUES STILL EXPECTED TO BE OVER 2
INCHES...RECORD TERRITORY FOR THE MONTH OF SEPTEMBER. THIS COUPLED
WITH GOOD FORCING FOR ASCENT ALONG AND AHEAD OF THE FRONT WILL
SUPPORT WIDESPREAD RAIN ON WEDNESDAY. TWO POSSIBLE IMPACTS TO
DISCUSS...SEVERE WEATHER AND HEAVY RAIN.
SEVERE WEATHER POTENTIAL WILL BE ENTIRELY DEPENDENT ON DEGREE OF
DIABATIC BOUNDARY LAYER HEATING EARLY IN THE DAY. 00Z NAM STILL A
RELATIVE OUTLIER IN SUGGESTING SBCAPE VALUES OF AROUND 2000
J/KG...PERPLEXING GIVEN THE DEGREE OF MORNING CLOUD COVER SEEN IN RH
FIELDS AND FORECAST SOUNDINGS. STILL PREFER THE MORE SUBDUED GFS
INSTABILITY VALUES GIVEN FAIRLY CONSISTENT RH/CLOUD FORECASTS SEEN
IN ALL OF THE MODELS. THAT BEING SAID...A SIGNIFICANT SEVERE WEATHER
OUTBREAK WILL BE POSSIBLE IF WE MANAGE TO GET ENOUGH SURFACE HEATING
BEFORE THE FRONT ARRIVES. KINEMATICS ARE EXCELLENT WITH 850MB WINDS
AT OR ABOVE 50 KTS AND GOOD DEEP LAYER SHEAR AS WELL. PRECIP LOADING
IN VERY MOIST ENVIRONMENT WILL HAVE LITTLE TROUBLE BRINGING STRONG
WIND CORE DOWN TO THE SURFACE WITH EVEN LIMITED INSTABILITY.
ISOLATED TORNADOES WILL ALSO BE A THREAT GIVEN LOW LCL`S AND STRONG
SHEAR. WHILE CURRENT EXPECTATIONS ARE FOR MORNING CLOUDS TO CURTAIL
THE SEVERE RISK SOMEWHAT...CONFIDENCE IN THIS SCENARIO IS NOT HIGH
AND EVERYONE SHOULD CONTINUE TO MONITOR THE LATEST FORECASTS CLOSELY
AS IT DOES NOT TAKE A LOT OF INSTABILITY TO GENERATE SIGNIFICANT
SEVERE WEATHER IN THESE HIGH SHEAR SITUATIONS. SUBTLE BOUNDARY LAYER
HEATING WILL MAKE THE DIFFERENCE BETWEEN A SIGNIFICANT OUTBREAK AND
A NONEVENT AND THAT IS DIFFICULT TO PINPOINT THIS FAR IN ADVANCE.
SOUTHEAST PORTIONS OF OUR CWA APPEAR TO HAVE THE BEST CHANCES FOR
SEVERE WEATHER AT THIS POINT...GIVEN FURTHER DISPLACEMENT FROM
MORNING PRECIP AND CLOUD DEBRIS.
THE OTHER IMPACT WILL BE POTENTIAL FOR HEAVY RAIN AND LOCALIZED
FLOODING. AGAIN...THIS WILL DEPEND SOMEWHAT ON DEGREE OF DIURNAL
DESTABILIZATION BUT EXPECT SOME HEALTHY RAINFALL AMOUNTS REGARDLESS
OF CONVECTIVE COMPONENT. AS PREVIOUSLY MENTIONED...TROPOSPHERIC
MOISTURE WILL BE UNUSUALLY HIGH. FORECAST SOUNDINGS SHOW A WARM
CLOUD LAYER OF AROUND 13 KFT...FAVORING EFFICIENT
COLLISION/COALESCENCE PROCESSES. MEAN FLOW VECTORS ARE ORIENTED A
BIT TOO ORTHOGONAL TO THE FRONT FOR A VERY LONG DURATION OF HEAVY
RAIN BUT SOME TRAINING WILL BE POSSIBLE. THIS WILL LEAD TO SOME
LOCALLY HEAVY RAIN GIVEN AVAILABLE MOISTURE AND PRECIP EFFICIENCY.
EXPECT MOST AREAS WILL SEE AROUND AN INCH WITH ISOLATED POCKETS OF
HIGHER AMOUNTS POSSIBLE.
MAINLY DRY CONDITIONS EXPECTED AFTER TOMORROW. A SECONDARY VORT MAX
WILL SWING THROUGH THE GREAT LAKES ON FRIDAY NIGHT AND MAY GENERATE
A FEW RAIN SHOWERS. MAIN STORY WILL BE MUCH COOLER CONDITIONS. 850MB
TEMPS EXPECTED TO DROP TO NEAR 0C BY THIS WEEKEND. ALSO EXPECTING A
HEALTHY CU/STRATOCU DECK ON THURSDAY AND FRIDAY TO KEEP A LID ON
AFTERNOON TEMPS. THIS SHOULD LEAD TO HIGH TEMPS IN THE LOW TO MID
60S THROUGH SUNDAY WITH OVERNIGHT LOWS IN THE LOW TO MID 40S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 636 AM EDT TUE SEP 9 2014
RADAR AND SURFACE OBS INDICATE SOME LIGHT RAIN IS REACHING THE
GROUND ACROSS NORTHEAST IL THIS MORNING BUT CONDITIONS ARE VFR
WITH MAINLY MID LEVEL CLOUDS. TRENDS SHOWING A WEAKENING STATE AND
SOUTHERN SINK TO MOVEMENT SO HAVE OPTED TO KEEP PCPN OUT OF KSBN
TAF WITH VFR CONDITIONS AND NO FLIGHT RESTRICTIONS ANTICIPATED.
EXPECT VFR THE REMAINDER OF PERIOD WITH ANY PRECIPITATION TONIGHT
REMAINING JUST WEST OF KSBN THROUGH 12Z WED.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
UPDATE...LASHLEY
SYNOPSIS...LASHLEY
SHORT TERM...LASHLEY
LONG TERM...AGD
AVIATION...LASHLEY
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
543 AM EDT TUE SEP 9 2014
.SYNOPSIS...
ISSUED AT 354 AM EDT TUE SEP 9 2014
AN AREA OF LOW PRESSURE WILL BEGIN ORGANIZING IN THE PLAINS TODAY
AND WILL STRENGTHEN CONSIDERABLY TONIGHT AS IT MOVES INTO THE
UPPER MISSISSIPPI VALLEY BY WEDNESDAY MORNING. MID AND UPPER LEVEL
CLOUDS WILL BE ACROSS OUR AREA TODAY. THERE IS A SMALL CHANCE FOR
SHOWERS IN THE FAR WEST THIS MORNING. HIGH TEMPERATURES SHOULD
CLIMB TO NEAR 80 ACROSS THE REGION. SKIES WILL BECOME MOSTLY
CLOUDY TONIGHT. THERE IS A CHANCE FOR SHOWERS AND THUNDERSTORMS
LATE ACROSS NORTHEAST ILLINOIS...NORTHWEST INDIANA AND SOUTHWEST
LOWER MICHIGAN. LOW TEMPERATURES WILL ONLY DROP INTO THE 60S AND
IT WILL FEEL MORE HUMID OVERNIGHT AS WELL.
&&
.UPDATE...
ISSUED AT 538 AM EDT TUE SEP 9 2014
PRECIPITATION ACROSS IL CONTINUES TO EXPAND EAST ALONG THETA E SURGE...ALBEIT
PCPN APPEARS TO BE LIGHT ON EASTERN FLANK. GETTING TOO CLOSE FOR
COMFORT AND 07Z HRRR NOW BRINGS SOME LIGHT QPF INTO FAR WESTERN
COUNTIES EARLY THIS MORNING. MOST OTHER HIRES GUIDANCE STILL
DEPICTS NO PCPN INTO OUR AREA BUT RADAR/SAT TRENDS SUGGEST A LOW
POP IS PRUDENT THIS MORNING ALONG WITH AN INCREASE IN CLOUD COVER.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 354 AM EDT TUE SEP 9 2014
THIS SHORT TERM PERIOD REMAINS QUIET BUT EXPECT INCREASING
MOISTURE DURING THE PERIOD AHEAD OF POTENT SHORT WAVE AND SURFACE
COLD FRONT APPROACHING FOR WEDNESDAY.
INITIAL THETA E SURGE RESPONSIBLE FOR CONVECTIVE DEVELOPMENT EARLY
THIS MORNING UPSTREAM ACROSS EASTERN IA AND NORTHWEST IL. RADAR
MOSAIC SHOWS THIS PCPN STRUGGLING TO MOVE EAST INTO DRIER AIR AND
MOST HIRES MODEL GUIDANCE KEEPS PCPN WEST OF OUR AREA TODAY. WILL
THEREFORE KEEP A DRY FORECAST INTACT TODAY BUT WILL SEE INITIAL
SURGE OF HIGHER THETA E AIR WORK EAST DURING THE DAY. MID AND HIGH
CLOUD COVER FROM UPSTREAM CONVECTION WILL PERSIST THIS MORNING AND
WILL LIKELY BE THIN AT TIMES DURING THE DAY. FILTERED SUNSHINE
EXPECTED. CLOUDS TO OFFSET WARMER 925-850MB TEMPS SO HIGHS TODAY
EXPECTED NEAR OR JUST ABOVE MONDAY TEMPS.
STRONG CYCLOGENESIS OCCURS TONIGHT IN THE PLAINS WITH POTENT SHORT
WAVE AND STRONG UPPER LEVEL JET DYNAMICS. SECONDARY THETA E SURGE
WILL APPROACH LATE TONIGHT BUT MAIN FORCING EXPECTED TO REMAIN WEST
OF OUR AREA UNTIL WEDNESDAY. ISENTROPIC UPGLIDE IS DEPICTED ON
MODELS WITH SOME SATURATION BUT EXPECT THIS TO GO MORE INTO CLOUD
FORMATION AND MOISTENING OF ATMOSPHERE. THETA E GRADIENT DOES ENTER
NORTHWEST AREAS LATE SO WILL KEEP A LOW CHANCE THERE LATE TONIGHT.
WITH INCREASING CLOUDS...GRADIENT AND MOISTURE EXPECT LOW TEMPS TO
REMAIN IN THE 60S. HAVE USED A WARMER BLEND OF GUIDANCE FOR LOWS.
&&
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 354 AM EDT TUE SEP 9 2014
ALL EYES ON WEDNESDAY`S SYSTEM WITH CHILLY TEMPS BEING THE ONLY
SENSIBLE WEATHER CONCERN FOR THE REST OF THE PERIOD. SHORTWAVE
TROUGH CURRENTLY OVER NORTHERN CALIFORNIA STILL EXPECTED TO EJECT
INTO THE CENTRAL PLAINS AND BECOME NEGATIVELY TILTED AS IT CROSSES
THE GREAT LAKES ON WEDNESDAY. AMPLIFYING LONGWAVE PATTERN WILL
SUPPORT A TIGHTENING BAROCLINIC ZONE ACROSS THE REGION AND COUPLED
UPPER LEVEL JET STREAKS WILL FAVOR STRONG CYCLOGENESIS ALONG THIS
BOUNDARY. SYNOPTIC SCALE DETAILS REMAIN CONSISTENT IN LATEST MODEL
SUITE. BEST PV ADVECTION AND DEFORMATION FORCING WILL PASS TO OUR
NORTHWEST CLOSER TO THE SURFACE LOW TRACK BUT GOOD MIDLEVEL HEIGHT
FALLS AND ASSOCIATED LOW LEVEL CONVERGENCE WILL STILL LEAD TO GOOD
FGEN ALONG TRAILING COLD FRONT. AS HAS BEEN DISCUSSED FOR SEVERAL
DAYS...THIS SYSTEM WILL HAVE AMPLE MOISTURE TO WORK WITH. DEEP
MONSOONAL MOISTURE CURRENTLY OVER THE SOUTHWEST CONUS WILL BE DRAWN
NORTH WITH THIS WAVE...ALONG WITH MOISTURE ADVECTION FROM THE
WESTERN GULF/SOUTHERN PLAINS. PW VALUES STILL EXPECTED TO BE OVER 2
INCHES...RECORD TERRITORY FOR THE MONTH OF SEPTEMBER. THIS COUPLED
WITH GOOD FORCING FOR ASCENT ALONG AND AHEAD OF THE FRONT WILL
SUPPORT WIDESPREAD RAIN ON WEDNESDAY. TWO POSSIBLE IMPACTS TO
DISCUSS...SEVERE WEATHER AND HEAVY RAIN.
SEVERE WEATHER POTENTIAL WILL BE ENTIRELY DEPENDENT ON DEGREE OF
DIABATIC BOUNDARY LAYER HEATING EARLY IN THE DAY. 00Z NAM STILL A
RELATIVE OUTLIER IN SUGGESTING SBCAPE VALUES OF AROUND 2000
J/KG...PERPLEXING GIVEN THE DEGREE OF MORNING CLOUD COVER SEEN IN RH
FIELDS AND FORECAST SOUNDINGS. STILL PREFER THE MORE SUBDUED GFS
INSTABILITY VALUES GIVEN FAIRLY CONSISTENT RH/CLOUD FORECASTS SEEN
IN ALL OF THE MODELS. THAT BEING SAID...A SIGNIFICANT SEVERE WEATHER
OUTBREAK WILL BE POSSIBLE IF WE MANAGE TO GET ENOUGH SURFACE HEATING
BEFORE THE FRONT ARRIVES. KINEMATICS ARE EXCELLENT WITH 850MB WINDS
AT OR ABOVE 50 KTS AND GOOD DEEP LAYER SHEAR AS WELL. PRECIP LOADING
IN VERY MOIST ENVIRONMENT WILL HAVE LITTLE TROUBLE BRINGING STRONG
WIND CORE DOWN TO THE SURFACE WITH EVEN LIMITED INSTABILITY.
ISOLATED TORNADOES WILL ALSO BE A THREAT GIVEN LOW LCL`S AND STRONG
SHEAR. WHILE CURRENT EXPECTATIONS ARE FOR MORNING CLOUDS TO CURTAIL
THE SEVERE RISK SOMEWHAT...CONFIDENCE IN THIS SCENARIO IS NOT HIGH
AND EVERYONE SHOULD CONTINUE TO MONITOR THE LATEST FORECASTS CLOSELY
AS IT DOES NOT TAKE A LOT OF INSTABILITY TO GENERATE SIGNIFICANT
SEVERE WEATHER IN THESE HIGH SHEAR SITUATIONS. SUBTLE BOUNDARY LAYER
HEATING WILL MAKE THE DIFFERENCE BETWEEN A SIGNIFICANT OUTBREAK AND
A NONEVENT AND THAT IS DIFFICULT TO PINPOINT THIS FAR IN ADVANCE.
SOUTHEAST PORTIONS OF OUR CWA APPEAR TO HAVE THE BEST CHANCES FOR
SEVERE WEATHER AT THIS POINT...GIVEN FURTHER DISPLACEMENT FROM
MORNING PRECIP AND CLOUD DEBRIS.
THE OTHER IMPACT WILL BE POTENTIAL FOR HEAVY RAIN AND LOCALIZED
FLOODING. AGAIN...THIS WILL DEPEND SOMEWHAT ON DEGREE OF DIURNAL
DESTABILIZATION BUT EXPECT SOME HEALTHY RAINFALL AMOUNTS REGARDLESS
OF CONVECTIVE COMPONENT. AS PREVIOUSLY MENTIONED...TROPOSPHERIC
MOISTURE WILL BE UNUSUALLY HIGH. FORECAST SOUNDINGS SHOW A WARM
CLOUD LAYER OF AROUND 13 KFT...FAVORING EFFICIENT
COLLISION/COALESCENCE PROCESSES. MEAN FLOW VECTORS ARE ORIENTED A
BIT TOO ORTHOGONAL TO THE FRONT FOR A VERY LONG DURATION OF HEAVY
RAIN BUT SOME TRAINING WILL BE POSSIBLE. THIS WILL LEAD TO SOME
LOCALLY HEAVY RAIN GIVEN AVAILABLE MOISTURE AND PRECIP EFFICIENCY.
EXPECT MOST AREAS WILL SEE AROUND AN INCH WITH ISOLATED POCKETS OF
HIGHER AMOUNTS POSSIBLE.
MAINLY DRY CONDITIONS EXPECTED AFTER TOMORROW. A SECONDARY VORT MAX
WILL SWING THROUGH THE GREAT LAKES ON FRIDAY NIGHT AND MAY GENERATE
A FEW RAIN SHOWERS. MAIN STORY WILL BE MUCH COOLER CONDITIONS. 850MB
TEMPS EXPECTED TO DROP TO NEAR 0C BY THIS WEEKEND. ALSO EXPECTING A
HEALTHY CU/STRATOCU DECK ON THURSDAY AND FRIDAY TO KEEP A LID ON
AFTERNOON TEMPS. THIS SHOULD LEAD TO HIGH TEMPS IN THE LOW TO MID
60S THROUGH SUNDAY WITH OVERNIGHT LOWS IN THE LOW TO MID 40S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 133 AM EDT TUE SEP 9 2014
STILL EXPECT VFR THROUGH THIS PERIOD AS HIGH PRESSURE SLIDES EAST
BUT STILL HAS CONTROL OVER OUR AREA. MOISTURE ADVECTION UPSTREAM
WILL SLOWLY INCREASE THIS PERIOD. SHOULD SEE INCREASE IN MID AND
HIGH LEVEL CLOUDS THROUGH THE DAY. A STRAY SPRINKLE OR VERY LIGHT
SHOWER NOT OUT OF QUESTION AT KSBN TUE MORNING BUT EXPECTING
DRIER AIR IN PLACE TO ERODE UPSTREAM PCPN AS IT MOVES EAST SO
CHANCES VERY MINIMAL AND NO IMPACT TO OPERATIONS WOULD BE
EXPECTED. MORE SIGNIFICANT WEATHER EXPECTED WEDNESDAY INTO
WEDNESDAY NIGHT WITH STRONG COLD FRONT.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
UPDATE...LASHLEY
SYNOPSIS...LASHLEY
SHORT TERM...LASHLEY
LONG TERM...AGD
AVIATION...LASHLEY
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AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
649 PM CDT WED SEP 10 2014
.SYNOPSIS...
ISSUED AT 323 PM CDT WED SEP 10 2014
LATEST SFC ANALYSIS WAS INDICATING SEASONABLY STRONG AND STILL
DEEPENING CYCLONE MOVING NORTHEASTWARD ACRS NORTHERN LK MICHIGAN...
WITH A TIGHT CYCLONIC GRADIENT IN IT/S WAKE ACRS WI AND EASTERN IA.
BUT STRONG RIDGE LOBE ALSO NOTED JUTTING DOWN THE PLAINS ALONG WITH
IT/S ASSOCIATED LLVL NORTHERLY COOL AIR INTRUSION ACRS THE UPPER
MIDWEST. AFTERNOON TEMPS IN THE 40S AND 50S ACRS THE DAKOTAS...MN...
WI AND EVEN MUCH OF NEB. WIDESPREAD WRAP-AROUND WAKE CLOUD SHIELD
ACRS THE REGION AS WELL...WITH SOME LIGHT SHOWERS AND SPRINKLES
GETTING WRUNG OUT CURRENTLY ACRS THE NORTH CENTRAL AND INTO THE
EASTERN DVN CWA ATTM. ALOFT...SEASONABLY IMPRESSIVE COOL CORE L/W
TROF WAS SEEN ON WATER VAPOR LOOP BUILDING DOWN ACRS MUCH OF THE
NORTHERN ROCKIES AND INTO THE WESTERN GRT LKS.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 323 PM CDT WED SEP 10 2014
TONIGHT...WITH THE BULK OF ANY LINGERING WRAP AROUND SHOWERS OR
SPRINKLES EXPECTED TO BE EAST AND SOUTHEAST OF THE DVN CWA AFTER
00Z THIS EVENING...THE MAIN FCST CHALLENGE TONIGHT IS IF THE CLOUDS
WILL CLEAR AT ALL TONIGHT...AS WELL AS EXTENT OF LOW TEMPS. SEVERAL
OF THE SHORT RANGE MODELS TRY TO BREAK OUT SOME OF THE CEILINGS BY
LATE TONIGHT...WHILE A FEW OTHERS MAINTAIN THE DECK INTO THU
MORNING. LOOKING AT FCST SOUNDINGS...POST-WAVE SUBSIDENCE AND LLVL
COOL AIR ADVECTION TO COMBINE TO FORM A INVERSION FROM H9-H75 MB
OVERNIGHT WHICH ACT AS A TRAPPING AGENT FOR ANY LINGERING LLVL
CLOUD DECK STILL IN PLACE. PUT W/V IMAGERY AND THE SAME FCST
SOUNDINGS ALSO SHOW DRYING AIR COLUMN ALOFT ABOVE THE INVERSION.
FOR NOW WILL PLAY THE CLOUDS MORE PESSIMISTIC OF CLEARING AND KEEP
CLOUDY TO MOSTLY CLOUDY SKIES GOING INTO THU MORNING. NORTHWESTERLY
TO NORTHERLY SFC WINDS OF 10-15 KTS TO MAINTAIN OVERNIGHT AS WELL
UNDER CLOUD COVER AND IN SFC PRESSURE GRADIENT BATTLE BETWEEN THE
WESTERN RIDGE AND DEPARTING LOW PRESSURE SYSTEM. THUS IT WILL HAVE
TO BE COOL AIR ADVECTION ITSELF ON THE NOSE OF THE LLVL NORTHERLIES
OUT OF MN TO GET THE FCST LOW TEMPS IN THE 40S.
THURSDAY...SKY COVER TO CONTINUE TO BE A CHALLENGE...WITH TOP-DOWN
DRYING TRYING TO MIX DOWN INTO THE TRAPPED LAYER UNDER THE INVERSION.
BUT SEE THE DRY AIR PARTIAL WINNING OUT FOR PERIODS OF PARTLY TO
MOSTLY SUNNY SKIES DURING THE MORNING AND MIDDAY. BUT ALSO SEE MORE
LLVL AMBIENT CU DEVELOPMENT FED FROM SFC MOISTURE EVAPORATION FROM
RECENT HEAVY RAINS INTO THE BOUNDARY LAYER FROM LATE MORNING THROUGH
MID AFTERNOON...BATTLING THE CLEARING PROCESS. MAY GO WITH PARTLY
SUNNY SKIES AS AN AVERAGE FOR THE DAY FOR NOW. ONGOING INVERSION
ALOFT TO LIMIT A DEEPER MIXING DEPTH AND WILL KEEP MOST HIGHS IN THE
DVN CWA IN THE LOW TO MID 60S. ..12..
.LONG TERM...(THURSDAY NIGHT THROUGH NEXT WEDNESDAY)
ISSUED AT 323 PM CDT WED SEP 10 2014
FORECAST FOCUS ON BELOW NORMAL TEMPERATURES THROUGH THIS PERIOD.
THURSDAY NIGHT AND FRIDAY...STRENGTHENING UPPER LEVEL TROUGH WILL
PROVIDE LARGE SCALE ASCENT WHICH WILL SQUEEZE OUT THE AVAILABLE
MOISTURE. THIS WILL BRING RAIN INTO OUR FAR NW CWA EARLY FRIDAY
MORNING WHICH WILL THEN SPREAD OVER ALL OF THE CWA DURING THE DAY.
EXTENSIVE CLOUD COVER AND RAIN WILL MAKE FOR A RATHER CHILLY DAY FOR
MID SEPTEMBER. RAINFALL AMOUNTS SHOULD BE LESS THAN A QUARTER OF AN
INCH. WILL CONTINUE TO FORECAST MAXIMUM TEMPERATURES FOR FRIDAY ONLY
IN THE MID 50S TO AROUND 60...WHICH WILL BE CLOSE TO RECORD COOL
HIGHS. (SEE CLIMATE SECTION BELOW). THESE READINGS ARE MORE TYPICAL
OF WHAT WOULD BE SEEN AT THE END OF OCTOBER OR EARLY NOVEMBER.
FRIDAY NIGHT INTO EARLY SATURDAY...THE RAIN WILL EXIT OUR EASTERN
CWA SOMETIME FRIDAY EVENING WITH DRY WEATHER RETURNING AFTER
MIDNIGHT. DEPENDING ON WHEN CLOUDS DEPART WILL DETERMINE HOW CHILLY
IT GETS BY EARLY SATURDAY MORNING. HIGH PRESSURE RIDGE WILL BE
BUILDING INTO THE AREA SO TIMING WILL BE EVERYTHING IN REGARDS TO
POTENTIAL FOR ANY FROST FORMATION. AS OF NOW OUR FAR NW CWA WOULD
HAVE THE COLDEST READINGS AS THAT AREA SHOULD CLEAR OUT THE SOONEST.
MINIMUM TEMPERATURES SHOULD RANGE FROM THE MID TO UPPER 30S NW TO
THE LOWER 40S SE. ECMWF BRINGS THE 0C 850 MB ISOTHERM INTO OUR
NORTHERN CWA BY 12Z SATURDAY.
THIS WEEKEND...LOOKS TO BE A SPECTACULAR WEEKEND BUT COOL AS
CANADIAN HIGH PRESSURE WILL SETTLE INTO THE REGION. HIGHS WILL BE
MOSTLY IN THE 60S WITH LOWS IN THE 40S. THERE IS THE POTENTIAL THAT
SATURDAY NIGHT WILL BE COOLER THAN FORECAST. THIS WILL DEPEND ON
EXACTLY WHERE THE HIGH PRESSURE RIDGE WILL BE LOCATED AND WIND
SPEEDS.
NEXT WEEK...CONTINUED BELOW NORMAL TEMPERATURES WITH PERSISTENT
NORTHWEST FLOW ALOFT. MODELS SUGGEST ANOTHER CHANCE OF RAIN ON
MONDAY WITH A SIGNIFICANT SHORT WAVE IN THE FLOW. MAXIMUM
TEMPERATURES PUSH INTO THE LOWER 70S AT MOST LOCATIONS...WITH LOWS
IN THE UPPER 40S TO LOWER 50S. HAASE
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 633 PM CDT WED SEP 10 2014
LARGE AREA OF STRATUS WITH MAINLY MVFR CIGS LIKELY TO PERSIST TNGT
AND THU... WITH CIGS MOSTLY AROUND 1500-2500 FT AGL. SOME OF THE
MOST RECENT HRRR AND RAP CLOUD BASE HEIGHT GUIDANCE SUGGESTS SOME
CLEARING WILL DEVELOP TONIGHT INTO THU AM...AND WILL CONTINUE TO
EVALUATE AND UPDATE IF THIS COMES TO FRUITION BUT FOR NOW WILL
MAINTAIN MVFR CIGS. NW WINDS WILL REMAIN AROUND 10 KTS TNGT
AND WILL SEE GUSTS MAINLY THIS EVE 15-25 KTS. THU WINDS WILL
VEER NORTHERLY AND REMAIN AROUND 10-15 KTS WITH SOME GUSTS POSSIBLE.
&&
.CLIMATE...
ISSUED AT 323 PM CDT WED SEP 10 2014
RECORD COOL HIGHS FOR FRIDAY SEP 12...
DUBUQUE... 53 SET IN 1902
MOLINE.... 55 SET IN 1902
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...12
SHORT TERM...12
LONG TERM...HAASE
AVIATION...05
CLIMATE...HAASE
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
557 PM CDT TUE SEP 9 2014
.SYNOPSIS...
ISSUED AT 330 PM CDT TUE SEP 9 2014
LOW PRESSURE OVER EXTREME SOUTHEAST CO HAD A WARM FRONT EXTENDED
INTO NORTHERN MO INTO SOUTHERN IL. TEMPERATURES TO THE SOUTH OF
THE FRONT WERE WELL IN THE 80S TO MID 90S WITH DEWPOINTS IN THE
LOWER TO MID 70S. SBCAPES OF 4000 J/KG WERE OCCURRING IN WESTERN
MO. TO THE NORTH OF THE FRONT IN THE RAIN COOLED AIR READINGS WERE
ONLY IN THE UPPER 60S TO UPPER 70S. THE BEST PRESSURE FALLS WERE
LOCATED IN WESTERN KS. PRECIPITABLE WATERS WERE AS HIGH AS 1.9 INCHES
IN NORTHERN MO.
DOPPLER RADAR CONTINUED TO SHOW FESTERING SHOWERS AND A FEW
THUNDERSTORMS FROM EASTERN NEB INTO SOUTHEAST IA AND CENTRAL IL
WITH WARM AIR ADVECTION INTO THE AREA.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 330 PM CDT TUE SEP 9 2014
HEADLINES...NOW THAT MUCH OF THE AREA HAS SATURATED SOILS THE
FLASH FLOOD WATCH WILL CONTINUE TONIGHT INTO WEDNESDAY MORNING
FOR THE ENTIRE CWA.
TONIGHT...ADDITIONAL RAINFALL OF 1 TO 3 INCHES APPEAR LIKELY. SOME
LOCATIONS MAY RECEIVE 4 TO 6 INCHES...ESPECIALLY IN ANY TRAINING/REPEATING
STORMS. THIS AMOUNT OF RAIN ON VERY SATURATED SOILS WOULD CAUSE SERIOUS
FLASH FLOODING. PRECIPITABLE WATERS WILL BE AT NEAR RECORD VALUES
FOR SEPTEMBER...ABOUT 2.2 INCHES. THIS IS DUE TO RICH GULF MOISTURE
COMBINED WITH MOISTURE FROM THE REMNANTS OF WHAT WAS MAJOR PACIFIC
HURRICANE NORBERT. RAINFALL RATES WILL BE EXTREMELY HIGH SO VERY
TORRENTIAL RAINS WILL ACCOMPANY THESE STORMS. CONFIDENCE IS VERY
HIGH FOR THIS FLASH FLOOD EVENT BUT IS LOWER FOR THE SEVERE THREAT.
THERE IS THE POTENTIAL FOR LOCALIZED WET MICROBURSTS DUE TO THE
VERY SATURATED ATMOSPHERE BUT ANY HAIL SHOULD REMAIN BELOW SEVERE
LEVELS. I AM CONCERNED FOR THE POTENTIAL FOR AN ISOLATED TORNADO
OR TWO ON ANY BOUNDARY AS THE DEEP LAYER SHEAR BECOMES VERY STRONG
EVEN WELL AFTER DARK AS THE SURFACE LOW DEEPENS AND TRACKS TOWARDS
LA CROSSE WI BY 12Z WEDNESDAY. THE HRRR MESO MODEL SUGGESTS ACTIVITY
INCREASING IN OUR SOUTHERN CWA LATE THIS AFTERNOON OR TOWARDS EVENING
THEN SPREADING NORTHEAST AS THE EVENING PROGRESSES...WITH WIDESPREAD
STORMS THEN OCCURRING OVERNIGHT. SOME OF THE STRONGER STORMS WILL
ALSO PRODUCE FREQUENT TO CONTINUOUS DANGEROUS LIGHTNING. MINIMUM
TEMPERATURES WILL BE IN THE MID 60S TO LOWER 70S.
WEDNESDAY...DEEPENING CYCLONE WILL TRACK INTO THE GREAT LAKES REGION
SENDING A STRONG COLD FRONT INTO OUR WESTERN CWA IN THE MORNING AND
OUR EASTERN CWA IN THE EARLY AFTERNOON. THE THUNDERSTORMS WILL GRADUALLY
DIMINISH AND SHIFT TO THE EAST OF THE CWA WITH THE FRONT. THE SEVERE
THREAT APPEARS TO BE FARTHER TO THE EAST THAN EARLIER THOUGHT AND SPC
HAS THE SLIGHT RISK ONLY IN OUR FAR SOUTHEAST COUNTIES...BUT THIS WILL
DEPEND ON CLOUD COVER AND AMOUNT OF INSTABILITY. MAXIMUM TEMPERATURES
SHOULD RANGE FROM THE UPPER 60S AT INDEPENDENCE IA TO THE UPPER 70S
IN OUR FAR EAST/SOUTHEAST COUNTIES.
.LONG TERM...(WEDNESDAY NIGHT THROUGH NEXT TUESDAY)
ISSUED AT 330 PM CDT TUE SEP 9 2014
WEDNESDAY NIGHT THROUGH FRIDAY...SEASONABLY STRONG RIDGE STILL ON
TRACK TO DUMP DOWN THE PLAINS AND UPPER MS RVR VALLEY THIS PERIOD.
EXPECT MOST POST-FRONTAL RAINS TO BE OUT OF THE CWA AT START OF THE
PERIOD...WITH JUST DEEPENING LLVL NORTHERLY FLOW COOL ADVECTING AND
SCORING OUT THE CLOUD COVER EVENTUALLY BY THU MORNING. EVEN IF CLOUD
COVER HOLDS ON TIL DAYLIGHT...LOWS TO BE ADVECTED DOWN INTO THE 40S
IN MOST OF THE CWA. INCOMING CANADIAN AIR TO WARM ONLY INTO THE 60S
THU EVEN WITH SOME SUNSHINE...WITH A QUICK DROP OFF AFTER SUNSET THU
EVENING INTO THE 40S BEFORE INCREASING CLOUDS AHEAD OF THE NEXT
SYSTEM TOWARD FRI MORNING HALTS TEMP DROP OFF. STILL SOME PHASING
ISSUES TO BE HAMMERED OUT...BUT LATEST RUN MEDIUM RANGE SOLUTIONS
SUGGEST SOME TYPE OF WAVE/POSSIBLY RATHER VIGOROUS...TO ROLL ACRS
THE REGION ON FRI. THIS SYSTEM WILL NOT HAVE NEAR THE MOISTURE
SOURCE OR THERMODYNAMICS TO WORK WITH AS THE CURRENT SYSTEM...BUT
STILL SHOULD INDUCE A RAIN SHIELD THAT WILL OVERSPREAD MOST OF THE
CWA FROM WEST TO EAST AS FRI PROGRESSES. CLOUD COVER AND PRECIP TO
KEEP A LID ON TEMPS WITH MOST AREAS HELD IN THE 50S OR EVEN UPPER 40S
AND NORTH WINDS MAKING FOR A RAW DAY. CURRENT INDICATIONS SUGGEST
MOST AREAS TO GET FROM 0.10 UP CLOSE TO HALF AN INCH BY THE TIME THE
RAIN PULLS OUT FRI EVENING. MODELS STILL VARYING ON PRECIP AND CLOUD
COVER EXIT TIMING LATER FRI NIGHT...BUT WILL JUST KEEP PRECIP IN THE
EVENING FOR NOW. POST-WAVE SUBSIDENCE MAY MAKE FOR A LATE NIGHT
CLEAR OUT...BUT SOME CHANCE FOR SUBSIDENCE INVERSION TO TRAP CLOUDS
INTO SAT MORNING LIMITING FRI NIGHT/SAT MORNING COLD POTENTIAL. THE
GFS CONTINUES TO BE THE COLD MODEL WITH SOME UPPER 30S IN THE
NORTHWESTERN THIRD OF THE DVN CWA AND LOWER 40S ELSEWHERE. THE ECMWF
MORE IN THE WAY OF LOW TO MID 40S BUT KEEPS THE CLOUD COVER AND SOME
MIXING SFC WINDS GOING INTO SAT MORNING. WITH EXTENT OF INCOMING
UNSEASONABLY COLD AIRMASS...FEEL WITH ANY KIND OF CLEAR OUT/PARTIAL
CLEARING AND SFC WIND DROP OFF UNDER 10 MPH LATE FRI NIGHT...THE
COOLER GFS WILL PREVAIL.
SATURDAY AND SUNDAY...HIGHS ONLY RECOVERING INTO THE UPPER 50S TO
MID 60S SAT UNDER WEAK MIXING REGIME OF CANADIAN HIGH PRESSURE...
THEN HOW COLD TO GO SAT NIGHT THE CHALLENGE. IF LLVL RETURN FLOW
DOES NOT MATERIALIZE IN TIME AND THE SFC RIDGE PERSISTS LONGER
BEFORE EASTWARD MIGRATION...SAT NIGHT MAY BE THE COOLER OF THE TWO
COLD WINDOW NIGHTS BEING WATCHED RIGHT NOW...MORE IDEAL RADIATIONAL
COOLING PARAMETERS IN LINE POSSIBLY. MORE WIDESPREAD MID TO UPPER 30S
POSSIBLE ESPECIALLY EAST OF THE MS RVR CLOSER TO RIDGE CENTER. WAA
ON BACK SIDE OF RIDGE COMPLEX MAY GENERATE SOME ELEVATED SHOWERS
INTO THE WESTERN CWA BY LAT SUNDAY NIGHT...BUT CONFIDENCE LOW ON
THAT SCENARIO.
MONDAY THROUGH NEXT TUESDAY...NEXT WAVE WILL LOOK TO SHEAR ACRS THE
UPPER MIDWEST SOMETIME THIS PERIOD FOR THE NEXT RAIN CHANCE...WITH
THE 12Z RUN ECMWF MORE PHASED AN ORGANIZED WITH THIS SYSTEM MON
NIGHT INTO TUE FOR MORE SIGNIFICANT PRECIP AS OPPOSED TO THE GFS. ..12..
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 550 PM CDT TUE SEP 9 2014
CONDITIONS TO DETERIORATE TO MVFR/OCNL IFR AS SHOWERS AND STORMS BECOME
WIDESPREAD LATER THIS EVE THROUGH EARLY WED AM AHEAD OF A STRONG
COLD FRONT. STORMS WILL BRING PERIODS OF VERY HEAVY RAIN... AND A FEW
MAY PRODUCE GUSTY WINDS AND HAIL. PCPN WILL DIMINISH IN COVERAGE AND
INTENSITY BY MID TO LATE WED AM... AS THE COLD FRONT BEGINS TO MOVE
INTO THE AREA. THE FRONT WILL LIKELY COME THROUGH THE TERMINALS BETWEEN
16Z-20Z BRINGING A WIND SHIFT TO THE NORTHWEST AROUND 10-15 KTS
WITH GUSTS POSSIBLE. SOME LOWER CIGS INTO IFR POSSIBLE ALONG AND BEHIND
THE FRONT FOR A TIME.
&&
.HYDROLOGY...
THE RIVER WATCH WILL BE ON THROUGH MID WEEK. AFTER LAST NIGHT/S AND
THIS MORNINGS RAINS...ANOTHER 1-4 INCHES TONIGHT INTO WED MORNING
WILL DEFINITELY PRODUCE SOME FLOODING ON AREA TRIBUTARIES...DEPENDING
ON HOW WIDESPREAD THE ADDITIONAL HEAVY RAIN WILL FALL IN THE LOCAL
AREA OF CONCERN. RIVER BASINS TO WATCH FOR FLOODING POTENTIAL ON SOME
OF THE FCST POINTS FROM WED THROUGH FRI MORNING ARE THE SKUNK...
CEDAR...IOWA...WAPSI...ENGLISH...AND DES MOINES RIVERS. THE
MAQUOKETA MAY GET CLOSE. IF NOT FLOODING THEN SIGNIFICANT WITHIN BANK
RISES TO OCCUR. ..12..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR BENTON-BUCHANAN-
CEDAR-CLINTON-DELAWARE-DES MOINES-DUBUQUE-HENRY IA-IOWA-
JACKSON-JEFFERSON-JOHNSON-JONES-KEOKUK-LEE-LINN-LOUISA-
MUSCATINE-SCOTT-VAN BUREN-WASHINGTON.
IL...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR BUREAU-CARROLL-
HANCOCK-HENDERSON-HENRY IL-JO DAVIESS-MCDONOUGH-MERCER-
PUTNAM-ROCK ISLAND-STEPHENSON-WARREN-WHITESIDE.
MO...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR CLARK-SCOTLAND.
&&
$$
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...12
AVIATION...05
HYDROLOGY...12
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
354 PM CDT TUE SEP 9 2014
.SYNOPSIS...
ISSUED AT 330 PM CDT TUE SEP 9 2014
LOW PRESSURE OVER EXTREME SOUTHEAST CO HAD A WARM FRONT EXTENDED
INTO NORTHERN MO INTO SOUTHERN IL. TEMPERATURES TO THE SOUTH OF
THE FRONT WERE WELL IN THE 80S TO MID 90S WITH DEWPOINTS IN THE
LOWER TO MID 70S. SBCAPES OF 4000 J/KG WERE OCCURRING IN WESTERN
MO. TO THE NORTH OF THE FRONT IN THE RAIN COOLED AIR READINGS WERE
ONLY IN THE UPPER 60S TO UPPER 70S. THE BEST PRESSURE FALLS WERE
LOCATED IN WESTERN KS. PRECIPITABLE WATERS WERE AS HIGH AS 1.9 INCHES
IN NORTHERN MO.
DOPPLER RADAR CONTINUED TO SHOW FESTERING SHOWERS AND A FEW
THUNDERSTORMS FROM EASTERN NEB INTO SOUTHEAST IA AND CENTRAL IL
WITH WARM AIR ADVECTION INTO THE AREA.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 330 PM CDT TUE SEP 9 2014
HEADLINES...NOW THAT MUCH OF THE AREA HAS SATURATED SOILS THE
FLASH FLOOD WATCH WILL CONTINUE TONIGHT INTO WEDNESDAY MORNING
FOR THE ENTIRE CWA.
TONIGHT...ADDITIONAL RAINFALL OF 1 TO 3 INCHES APPEAR LIKELY. SOME
LOCATIONS MAY RECEIVE 4 TO 6 INCHES...ESPECIALLY IN ANY TRAINING/REPEATING
STORMS. THIS AMOUNT OF RAIN ON VERY SATURATED SOILS WOULD CAUSE SERIOUS
FLASH FLOODING. PRECIPITABLE WATERS WILL BE AT NEAR RECORD VALUES
FOR SEPTEMBER...ABOUT 2.2 INCHES. THIS IS DUE TO RICH GULF MOISTURE
COMBINED WITH MOISTURE FROM THE REMNANTS OF WHAT WAS MAJOR PACIFIC
HURRICANE NORBERT. RAINFALL RATES WILL BE EXTREMELY HIGH SO VERY
TORRENTIAL RAINS WILL ACCOMPANY THESE STORMS. CONFIDENCE IS VERY
HIGH FOR THIS FLASH FLOOD EVENT BUT IS LOWER FOR THE SEVERE THREAT.
THERE IS THE POTENTIAL FOR LOCALIZED WET MICROBURSTS DUE TO THE
VERY SATURATED ATMOSPHERE BUT ANY HAIL SHOULD REMAIN BELOW SEVERE
LEVELS. I AM CONCERNED FOR THE POTENTIAL FOR AN ISOLATED TORNADO
OR TWO ON ANY BOUNDARY AS THE DEEP LAYER SHEAR BECOMES VERY STRONG
EVEN WELL AFTER DARK AS THE SURFACE LOW DEEPENS AND TRACKS TOWARDS
LA CROSSE WI BY 12Z WEDNESDAY. THE HRRR MESO MODEL SUGGESTS ACTIVITY
INCREASING IN OUR SOUTHERN CWA LATE THIS AFTERNOON OR TOWARDS EVENING
THEN SPREADING NORTHEAST AS THE EVENING PROGRESSES...WITH WIDESPREAD
STORMS THEN OCCURRING OVERNIGHT. SOME OF THE STRONGER STORMS WILL
ALSO PRODUCE FREQUENT TO CONTINUOUS DANGEROUS LIGHTNING. MINIMUM
TEMPERATURES WILL BE IN THE MID 60S TO LOWER 70S.
WEDNESDAY...DEEPENING CYCLONE WILL TRACK INTO THE GREAT LAKES REGION
SENDING A STRONG COLD FRONT INTO OUR WESTERN CWA IN THE MORNING AND
OUR EASTERN CWA IN THE EARLY AFTERNOON. THE THUNDERSTORMS WILL GRADUALLY
DIMINISH AND SHIFT TO THE EAST OF THE CWA WITH THE FRONT. THE SEVERE
THREAT APPEARS TO BE FARTHER TO THE EAST THAN EARLIER THOUGHT AND SPC
HAS THE SLIGHT RISK ONLY IN OUR FAR SOUTHEAST COUNTIES...BUT THIS WILL
DEPEND ON CLOUD COVER AND AMOUNT OF INSTABILITY. MAXIMUM TEMPERATURES
SHOULD RANGE FROM THE UPPER 60S AT INDEPENDENCE IA TO THE UPPER 70S
IN OUR FAR EAST/SOUTHEAST COUNTIES.
.LONG TERM...(WEDNESDAY NIGHT THROUGH NEXT TUESDAY)
ISSUED AT 330 PM CDT TUE SEP 9 2014
WEDNESDAY NIGHT THROUGH FRIDAY...SEASONABLY STRONG RIDGE STILL ON
TRACK TO DUMP DOWN THE PLAINS AND UPPER MS RVR VALLEY THIS PERIOD.
EXPECT MOST POST-FRONTAL RAINS TO BE OUT OF THE CWA AT START OF THE
PERIOD...WITH JUST DEEPENING LLVL NORTHERLY FLOW COOL ADVECTING AND
SCORING OUT THE CLOUD COVER EVENTUALLY BY THU MORNING. EVEN IF CLOUD
COVER HOLDS ON TIL DAYLIGHT...LOWS TO BE ADVECTED DOWN INTO THE 40S
IN MOST OF THE CWA. INCOMING CANADIAN AIR TO WARM ONLY INTO THE 60S
THU EVEN WITH SOME SUNSHINE...WITH A QUICK DROP OFF AFTER SUNSET THU
EVENING INTO THE 40S BEFORE INCREASING CLOUDS AHEAD OF THE NEXT
SYSTEM TOWARD FRI MORNING HALTS TEMP DROP OFF. STILL SOME PHASING
ISSUES TO BE HAMMERED OUT...BUT LATEST RUN MEDIUM RANGE SOLUTIONS
SUGGEST SOME TYPE OF WAVE/POSSIBLY RATHER VIGOROUS...TO ROLL ACRS
THE REGION ON FRI. THIS SYSTEM WILL NOT HAVE NEAR THE MOISTURE
SOURCE OR THERMODYNAMICS TO WORK WITH AS THE CURRENT SYSTEM...BUT
STILL SHOULD INDUCE A RAIN SHIELD THAT WILL OVERSPREAD MOST OF THE
CWA FROM WEST TO EAST AS FRI PROGRESSES. CLOUD COVER AND PRECIP TO
KEEP A LID ON TEMPS WITH MOST AREAS HELD IN THE 50S OR EVEN UPPER 40S
AND NORTH WINDS MAKING FOR A RAW DAY. CURRENT INDICATIONS SUGGEST
MOST AREAS TO GET FROM 0.10 UP CLOSE TO HALF AN INCH BY THE TIME THE
RAIN PULLS OUT FRI EVENING. MODELS STILL VARYING ON PRECIP AND CLOUD
COVER EXIT TIMING LATER FRI NIGHT...BUT WILL JUST KEEP PRECIP IN THE
EVENING FOR NOW. POST-WAVE SUBSIDENCE MAY MAKE FOR A LATE NIGHT
CLEAR OUT...BUT SOME CHANCE FOR SUBSIDENCE INVERSION TO TRAP CLOUDS
INTO SAT MORNING LIMITING FRI NIGHT/SAT MORNING COLD POTENTIAL. THE
GFS CONTINUES TO BE THE COLD MODEL WITH SOME UPPER 30S IN THE
NORTHWESTERN THIRD OF THE DVN CWA AND LOWER 40S ELSEWHERE. THE ECMWF
MORE IN THE WAY OF LOW TO MID 40S BUT KEEPS THE CLOUD COVER AND SOME
MIXING SFC WINDS GOING INTO SAT MORNING. WITH EXTENT OF INCOMING
UNSEASONABLY COLD AIRMASS...FEEL WITH ANY KIND OF CLEAR OUT/PARTIAL
CLEARING AND SFC WIND DROP OFF UNDER 10 MPH LATE FRI NIGHT...THE
COOLER GFS WILL PREVAIL.
SATURDAY AND SUNDAY...HIGHS ONLY RECOVERING INTO THE UPPER 50S TO
MID 60S SAT UNDER WEAK MIXING REGIME OF CANADIAN HIGH PRESSURE...
THEN HOW COLD TO GO SAT NIGHT THE CHALLENGE. IF LLVL RETURN FLOW
DOES NOT MATERIALIZE IN TIME AND THE SFC RIDGE PERSISTS LONGER
BEFORE EASTWARD MIGRATION...SAT NIGHT MAY BE THE COOLER OF THE TWO
COLD WINDOW NIGHTS BEING WATCHED RIGHT NOW...MORE IDEAL RADIATIONAL
COOLING PARAMETERS IN LINE POSSIBLY. MORE WIDESPREAD MID TO UPPER 30S
POSSIBLE ESPECIALLY EAST OF THE MS RVR CLOSER TO RIDGE CENTER. WAA
ON BACK SIDE OF RIDGE COMPLEX MAY GENERATE SOME ELEVATED SHOWERS
INTO THE WESTERN CWA BY LAT SUNDAY NIGHT...BUT CONFIDENCE LOW ON
THAT SCENARIO.
MONDAY THROUGH NEXT TUESDAY...NEXT WAVE WILL LOOK TO SHEAR ACRS THE
UPPER MIDWEST SOMETIME THIS PERIOD FOR THE NEXT RAIN CHANCE...WITH
THE 12Z RUN ECMWF MORE PHASED AN ORGANIZED WITH THIS SYSTEM MON
NIGHT INTO TUE FOR MORE SIGNIFICANT PRECIP AS OPPOSED TO THE GFS. ..12..
&&
.HYDROLOGY...
THE RIVER WATCH WILL BE ON THROUGH MID WEEK. AFTER LAST NIGHT/S AND
THIS MORNINGS RAINS...ANOTHER 1-4 INCHES TONIGHT INTO WED MORNING
WILL DEFINITELY PRODUCE SOME FLOODING ON AREA TRIBUTARIES...DEPENDING
ON HOW WIDESPREAD THE ADDITIONAL HEAVY RAIN WILL FALL IN THE LOCAL
AREA OF CONCERN. RIVER BASINS TO WATCH FOR FLOODING POTENTIAL ON SOME
OF THE FCST POINTS FROM WED THROUGH FRI MORNING ARE THE SKUNK...
CEDAR...IOWA...WAPSI...ENGLISH...AND DES MOINES RIVERS. THE
MAQUOKETA MAY GET CLOSE. IF NOT FLOODING THEN SIGNIFICANT WITHIN BANK
RISES TO OCCUR. ..12..
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 330 PM CDT TUE SEP 9 2014
ISOLATED TO SCATTERED THUNDERSTORMS EXPECTED THIS AFTERNOON IN THE
KBRL AREA THEN STORMS INTENSIFYING AND SPREADING NORTHEAST OVER
THE ENTIRE TAF SITES THIS EVENING AND BECOMING WIDESPREAD OVERNIGHT.
MVFR/OCNL IFR CONDS IN THUNDERSTORMS WITH VERY TORRENTIAL RAINS.
LOCALLY DAMAGING WINDS ARE POSSIBLE. SOUTH WINDS 10 TO 20 KNOTS
THIS AFTERNOON AND TONIGHT THEN BECOMING SOUTHWEST AROUND 15 KNOTS
WEDNESDAY WITH GUSTS TO AROUND 20 TO 25 KNOTS.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...FLASH FLOOD WATCH FROM 7 PM CDT THIS EVENING THROUGH WEDNESDAY
MORNING FOR BENTON-BUCHANAN-CEDAR-CLINTON-DELAWARE-DES
MOINES-DUBUQUE-HENRY IA-IOWA-JACKSON-JEFFERSON-JOHNSON-
JONES-KEOKUK-LEE-LINN-LOUISA-MUSCATINE-SCOTT-VAN BUREN-
WASHINGTON.
IL...FLASH FLOOD WATCH FROM 7 PM CDT THIS EVENING THROUGH WEDNESDAY
MORNING FOR BUREAU-CARROLL-HANCOCK-HENDERSON-HENRY IL-JO
DAVIESS-MCDONOUGH-MERCER-PUTNAM-ROCK ISLAND-STEPHENSON-
WARREN-WHITESIDE.
MO...FLASH FLOOD WATCH FROM 7 PM CDT THIS EVENING THROUGH WEDNESDAY
MORNING FOR CLARK-SCOTLAND.
&&
$$
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...12
HYDROLOGY...12
AVIATION...HAASE
AREA FORECAST DISCUSSION...CORRECTION
NWS QUAD CITIES IA IL
1242 PM CDT TUE SEP 9 2014
.UPDATE...
ISSUED AT 1240 PM CDT TUE SEP 9 2014
RAINFALL AMOUNTS FROM LAST NIGHT INTO THIS MORNING WERE IN THE 1 TO 3
INCH RANGE ACROSS MUCH OF EASTERN IA INTO WESTERN IL. THERE WERE ISOLATED
REPORTS OF 5 INCHES IN LINN COUNTY IA. NOW THAT MUCH OF THE AREA
HAS SATURATED SOILS I HAVE EXPANDED THE FLASH FLOOD WATCH TO INCLUDE
THE ENTIRE CWA FOR TONIGHT INTO WEDNESDAY MORNING. ADDITIONAL RAINFALL
OF 1 TO 3 INCHES APPEAR LIKELY TONIGHT. SOME LOCATIONS MAY RECEIVE
4 TO 6 INCHES...ESPECIALLY IN TRAINING/REPEATING STORMS. PRECIPITABLE
WATERS WILL BE AT RECORD VALUES FOR SEPTEMBER...ABOUT 2.4 INCHES.
RAINFALL RATES WILL BE EXTREMELY HIGH SO VERY TORRENTIAL RAINS
WILL ACCOMPANY THESE STORMS. CONFIDENCE IS VERY HIGH FOR THIS FLASH
FLOOD EVENT BUT IS LOWER FOR THE SEVERE THREAT. THERE IS THE POTENTIAL
FOR LOCALIZED WET MICROBURSTS DUE TO THE VERY SATURATED ATMOSPHERE
BUT ANY HAIL SHOULD REMAIN BELOW SEVERE LEVELS. I AM CONCERNED FOR
THE POTENTIAL FOR AN ISOLATED TORNADO OR TWO AS THE DEEP LAYER SHEAR
BECOMES VERY STRONG EVEN WELL AFTER DARK AS THE SURFACE LOW DEEPENS
AND TRACKS TOWARDS LACROSSE WI BY 12Z WEDNESDAY. THE HRRR MESO MODEL
SUGGESTS ACTIVITY INCREASING IN OUR SOUTHERN CWA THIS AFTERNOON THEN
SPREADING NORTHEAST AS THE EVENING PROGRESSES...WITH WIDESPREAD STORMS
THEN OCCURRING OVERNIGHT. RIVER FLOODING WILL THEN BECOME A CONCERN
ON TRIBUTARY RIVERS AS THE WEEK PROGRESSES.
&&
.SYNOPSIS...
ISSUED AT 307 AM CDT TUE SEP 9 2014
A SMALL BUT INTENSE MCS CONTINUES TO PRODUCED REPEAT/TRAINING STORMS
OVER MY CENTRAL CWA...AND HAS PLACED MUCH OF OUR METRO AREAS OF THE
QUAD CITIES/IOWA CITY/MUSCATINE/TIPTON/CEDAR RAPIDS INTO A SITUATION
WHERE FLASH FLOODING IS A DISTINCT RISK NOW AND AGAIN TONIGHT. I
WILL BE ISSUING A FLASH FLOOD WATCH FOR MY IOWA COUNTIES NORTHWEST OF
BURLINGTON. NORTHWEST ILLINOIS HAS NOT SEEN DEEP CONVECTION...AND
WILL BE LEFT OUT FOR NOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 307 AM CDT TUE SEP 9 2014
THE HARDEST QUESTION TODAY IS HOW LONG THE CURRENT MCS LASTS.
TONIGHT IS A FLAT OUT GUARANTEED WIDESPREAD CONVECTIVE EVENT. SINCE
WE HAVE SEEN 1 TO 4 INCHES ALREADY OVERNIGHT...AND MORE MAY YET
FALL...THERE IS DEFINITELY A THREAT FOR FLASH FLOODING WITH THIS
WIDESPREAD EVENT TONIGHT. WPC IS FORECASTING A MODERATE RISK FOR
EXCESSIVE/FLASH FLOOD RAINS TONIGHT OVER OUR WESTERN 1/2...THUS A
WATCH IS JUSTIFIED. SEVERE WEATHER MAY DECREASE AS IT APPROACHES
OUR CWA BUT CANNOT BE RULED OUT. THE EVENT FORCING PEAKS BETWEEN
03Z AND 12Z TONIGHT...AND 100 PERCENT POPS ARE BEING USED. A
WIDESPREAD 1 TO 3 INCHES SEEMS LIKELY TONIGHT...ON TOP OF THE 1 TO
4+ INCHES THAT HAS FALLEN SO FAR THIS CURRENT NIGHT. FLASH FLOOD
HIGHLIGHTS WILL DOMINATE OUT PRODUCT SUITE TODAY.
ERVIN
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 307 AM CDT TUE SEP 9 2014
A LARGE THUNDERSTORM COMPLEX WILL BE OVER THE AREA AT SUNRISE
WEDNESDAY THAT WILL SLOWLY DECAY AND MOVE EAST OF THE AREA. THE
MORNING HOURS WILL HAVE THE BEST CHANCES OF SEEING WIDESPREAD
RAINFALL...ESPECIALLY ALONG AND EAST OF THE MISSISSIPPI.
BOUNDARIES LEFT OVER FROM THIS THUNDERSTORM COMPLEX WILL COMBINE
WITH THE APPROACHING FRONT AND PROVIDE THE FOCUS FOR NEW
THUNDERSTORMS DURING THE AFTERNOON HOURS. AREAS EAST OF THE
MISSISSIPPI AND GENERALLY SOUTH OF I-80 WILL HAVE THE BEST CHANCE AT
SEEING NEW STORMS DURING THE AFTERNOON.
STORMS THAT DEVELOP WEDNESDAY AFTERNOON WILL LINGER INTO THE EVENING
HOURS BEFORE MOVING EAST OF THE AREA. DRY CONDITIONS ARE EXPECTED
AFTER MIDNIGHT AS HIGH PRESSURE STARTS BUILDING INTO THE MIDWEST.
DRY AND COOL CONDITIONS WILL BE SEEN ON THURSDAY WITH AN INCREASE IN
CLOUDS DURING THE AFTERNOON. TEMPERATURES WILL AVERAGE WELL BELOW
NORMAL.
DRY CONDITIONS WILL CONTINUE INTO THURSDAY EVENING. A WEAK
DISTURBANCE MOVING EAST FROM THE PLAINS WILL SPREAD LIGHT RAIN INTO
THE FAR WESTERN AREAS AFTER MIDNIGHT.
FRIDAY ON...
THE MODEL CONSENSUS HAS LIGHT RAIN MOVING ACROSS THE AREA ON FRIDAY
WITH RAIN ENDING FRIDAY NIGHT. TEMPERATURES WILL BE UNSEASONABLY
COOL WITH MOST AREAS NOT GETTING ABOVE 60 DEGREES.
THE MODEL CONSENSUS HAS DRY CONDITIONS FOR SATURDAY AND SUNDAY AS
HIGH PRESSURE MOVES THROUGH THE MIDWEST. TEMPERATURES WILL BE WELL
BELOW NORMAL.
SUNDAY NIGHT AND MONDAY THE MODEL CONSENSUS HAS SLIGHT CHANCE POPS
AS A WEAK DISTURBANCE MOVES THROUGH THE AREA. TEMPERATURES WILL
BEGIN MODERATING BUT STILL BE WELL BELOW NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1240 PM CDT TUE SEP 9 2014
ISOLATED TO SCATTERED THUNDERSTORMS EXPECTED THIS AFTERNOON IN THE
KBRL AREA THEN STORMS INTENSIFYING AND SPREADING NORTHEAST OVER
THE ENTIRE TAF SITES THIS EVENING AND BECOMING WIDESPREAD OVERNIGHT.
MVFR/OCNL IFR CONDS IN THUNDERSTORMS WITH VERY TORRENTIAL RAINS.
LOCALLY DAMAGING WINDS ARE POSSIBLE. SOUTH WINDS 10 TO 20 KNOTS
THIS AFTERNOON AND TONIGHT THEN BECOMING SOUTHWEST AROUND 15 KNOTS
WEDNESDAY WITH GUSTS TO AROUND 20 TO 25 KNOTS.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...FLASH FLOOD WATCH FROM 7 PM CDT THIS EVENING THROUGH WEDNESDAY
MORNING FOR BENTON-BUCHANAN-CEDAR-CLINTON-DELAWARE-DES
MOINES-DUBUQUE-HENRY IA-IOWA-JACKSON-JEFFERSON-JOHNSON-
JONES-KEOKUK-LEE-LINN-LOUISA-MUSCATINE-SCOTT-VAN BUREN-
WASHINGTON.
IL...FLASH FLOOD WATCH FROM 7 PM CDT THIS EVENING THROUGH WEDNESDAY
MORNING FOR BUREAU-CARROLL-HANCOCK-HENDERSON-HENRY IL-JO
DAVIESS-MCDONOUGH-MERCER-PUTNAM-ROCK ISLAND-STEPHENSON-
WARREN-WHITESIDE.
MO...FLASH FLOOD WATCH FROM 7 PM CDT THIS EVENING THROUGH WEDNESDAY
MORNING FOR CLARK-SCOTLAND.
&&
$$
UPDATE...HAASE
SYNOPSIS...ERVIN
SHORT TERM...ERVIN
LONG TERM...08
AVIATION...HAASE
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
316 PM CDT TUE SEP 9 2014
...UPDATED LONG TERM...
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 204 PM CDT TUE SEP 9 2014
LATEST RAP 400MB POTENTIAL VORTICITY APPEARS TO HAVE A DECENT
HANDLE WITH AN UPPER LEVEL DISTURBANCE THAT WAS CROSSING THE
COLORADO ROCKIES AT 18Z. GIVEN THE 18Z VERIFICATION WILL STAY
CLOSE TO THE RAP ON TIMING OF THIS UPPER LEVEL FEATURE AS IT
CROSSES EASTERN COLORADO AND WESTERN KANSAS LATER THIS EVENING.
GIVEN LATE DAY INSTABILITY AND LOCATION OF LOW LEVEL FORCING AHEAD
OF THIS UPPER LEVEL TROUGH NEAR A SURFACE BOUNDARY THAT WILL
EXTEND FROM SOUTHEAST COLORADO INTO NORTH CENTRAL KANSAS THERE
WILL BE A CHANCE FOR SCATTERED THUNDERSTORMS LATE THIS AFTERNOON
ACROSS NORTH CENTRAL KANSAS AND PORTIONS OF WEST KANSAS. BASED ON
THE 21Z TUESDAY AND 00Z WEDNESDAY CAPE AND 0-6KM SHEAR FROM THE
NAM A FEW STORMS LATE TODAY MAY BE SEVERE WITH THE AREA MORE
FAVORABLE FOR HAIL GOLF BALL SIZE OR LARGER ALONG WITH WIND GUST
IN EXCESS OF 60 MPH WILL BE ALONG AND NORTH OF A DIGHTON AND
LARNED LINE.
THUNDERSTORMS WILL THEN INCREASE IN AREAL COVERAGE EARLY TONIGHT
AS THE UPPER LEVEL DISTURBANCE CROSSES THE CENTRAL HIGH PLAINS AND
A SURFACE BOUNDARY MOVES ACROSS SOUTHWEST KANSAS. THE AREA THAT
WILL BE MORE FAVORABLE FOR WIDESPREAD THUNDERSTORMS EARLY TONIGHT
WILL BE ALONG AND NORTH OF A 700MB +10C TO +13C BAROCLINIC ZONE.
GIVEN THE 12Z NAM AND 12Z GFS THIS FAVORABLE AREA WILL BE
NORTHEAST OF A SYRACUSE TO DODGE CITY THE PRATT LINE. ALSO GIVEN
THE HIGH PRECIPITABLE WATER VALUES PERIODS THERE WILL BE A CHANCE
FOR PERIODS OF HEAVY RAIN IN THIS AREA AS WELL.
BUFR SOUNDINGS INDICATING WINDS NEAR THE SURFACE BEHIND THE COLD
FRONT WILL RANGE FROM 20 TO 30 KNOTS AS THE LOWER LEVELS BEGIN TO
SATURATE. BY 12Z WEDNESDAY THE DEPTH OF THIS LOW LEVEL MOISTURE
APPROACHES 3000FT WHICH SUPPORTS INSERTING A SLIGHT CHANCE FOR
LIGHT DRIZZLE FOR SEVERAL HOURS EARLY WEDNESDAY MORNING. BY LATE
MORNING THIS LOW LEVEL MOISTURE WILL BEGIN TO ERODE FROM SOUTHWEST
NORTHEAST AND GIVEN SOME AFTERNOON SUNSHINE ACROSS SOUTHWEST AND
SOUTH CENTRAL KANSAS THE HIGHS ARE EXPECTED TO CLIMB BACK INTO THE
MID 70S BASED ON THE 00Z THURSDAY 850MB TEMPERATURES. FURTHER
NORTH, NEAR THE INTERSTATE 70 CORRIDOR THE CLOUDS AND 850MB
TEMPERATURES AT 00Z THURSDAY SUGGEST HIGHS ON IN THE UPPER 60S TO
NEAR 70.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 313 PM CDT TUE SEP 9 2014
THE TREND WILL BE FOR COOLER AND WETTER IN THE VERY EARLY PERIOD
OF THE LONG TERM FORECAST. THE PERIOD FROM WEDNESDAY INTO THE
BEGINNING OF THE WEEKEND WILL THEN BE FOLLOWED BY A MODERATE
REBOUND BACK TOWARD THE 80S BY THE MIDDLE OF NEXT WEEK.
ALL THREE MODELS, THE ECMWF, GFS AND NAM INDICATED PRECIPITATION
ALONG A STRONG FRONTOGENETIC ZONE ACROSS CENTRAL AND FAR WESTERN
KANSAS INTO SOUTHEAST COLORADO FROM LATE THURSDAY NIGHT AND
SPREADING EAST OVER CENTRAL KANSAS FRIDAY MORNING. SOME VARIABILITY
IS EXPECTED AS THE BETTER FORCING IN THE MID LEVELS IS NOT EXPECTED
TO SLIDE ALL THE WAY THROUGH THE CWA INTO OKLAHOMA, HENCE A BAND OF
HIGHER RAIN AMOUNTS COULD FALL SOMEWHERE FROM THE HIGHWAY 54
CORRIDOR NORTHWARD AS THE NAM SUGGESTS. OTHER LOCATIONS SHOULD STILL
GET SOME, BUT GENERALLY MUCH LIGHTER PRECIPITATION AMOUNTS OF A FEW
HUNDREDTHS AS THE SECONDARY FRONTAL BOUNDARY MOVES THROUGH THE
REGION IN THE FORM OF SCATTERED SHOWERS IF NOT A PERIOD OF RAIN. OF
MUCH LONGER DURATION AND IMPACT WILL BE THE WIDESPREAD STRATUS
THROUGH THE AREA, INHIBITING INSOLATION AND ENHANCING COLD
ADVECTION. THE NUMEROUS MODELS AND BLEND SOLUTIONS STRONGLY SUPPORTS
LOW 50S ACROSS MUCH OF THE AREA FOR A HIGH TEMPERATURES ON FRIDAYS.
TEMPERATURES THIS COOL WILL REPRESENT ONLY A FEW DEGREES ABOVE
RECORD MIN-MAXIMUM TEMPERATURES FOR SEPTEMBER 12TH AT LEAST LOCALLY
AT DDC.
A WARMING TEND WILL BE SLOW THROUGH THE WEEKEND PERIOD. THE MEAN
LAYER WILL RETURN TO GENERALLY ZONAL PATTERN BY SUNDAY AFTER THE
LARGE WAVE EXISTS. THE NEXT WAVE WILL NOT BECOME A POTENTIAL IMPACT
UNTIL AROUND LATE SUNDAY OR MONDAY. THE PATTERN SUGGEST SOUTHWEST
KANSAS COULD BE SPLIT AS FAR AS UPPER DYNAMIC FORCING GOES, WITH
POSSIBLE MCS ACTIVITY TO THE NORTH IN THE DAKOTAS AND NEBRASKA AND
SHORTWAVE ENERGY IN THE PANHANDLES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1208 PM CDT TUE SEP 9 2014
WIDELY SCATTERED THUNDERSTORMS WILL BE POSSIBLE AFTER 21Z ALONG
AND NORTH OF A GARDEN CITY TO HAYS LINE AS MID LEVEL MOISTURE AND
INSTABILITY INCREASES AHEAD OF AN UPPER LEVEL DISTURBANCE THAT
WILL BEGIN TO EXIT THE ROCKIES AND MOVE OUT INTO THE CENTRAL HIGH
PLAINS. THUNDERSTORMS WILL INCREASE IN AREAL COVERAGE EARLY
TONIGHT AS THIS UPPER LEVEL TROUGH CROSSES THE CENTRAL HIGH PLAINS
AND A SURFACE COLD FRONT CROSSES WESTERN KANSAS. AS THE COLD FRONT
PASSES THE CONVECTION WILL TAPER OFF, HOWEVER GUSTY NORTH WINDS AT
20 TO NEAR 25 KNOTS WILL DEVELOP BEHIND THIS FRONT ALONG WITH
INCREASING LOW LEVEL MOISTURE. BASED ON BUFR SOUNDINGS CEILINGS
BETWEEN 700 AND 1500FT AGL IS EXPECTED AFTER 09Z AT HAYS AND
BETWEEN 12Z AND 15Z AT GARDEN CITY AND DODGE CITY.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 63 73 49 65 / 40 10 0 10
GCK 62 73 49 63 / 50 20 10 10
EHA 62 75 52 69 / 20 10 10 10
LBL 64 76 51 67 / 20 10 0 10
HYS 62 68 45 62 / 70 20 0 10
P28 70 78 53 71 / 30 10 0 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...RUSSELL
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
205 PM CDT TUE SEP 9 2014
...UPDATED SHORT TERM DISCUSSION...
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 204 PM CDT TUE SEP 9 2014
LATEST RAP 400MB POTENTIAL VORTICITY APPEARS TO HAVE A DECENT
HANDLE WITH AN UPPER LEVEL DISTURBANCE THAT WAS CROSSING THE
COLORADO ROCKIES AT 18Z. GIVEN THE 18Z VERIFICATION WILL STAY
CLOSE TO THE RAP ON TIMING OF THIS UPPER LEVEL FEATURE AS IT
CROSSES EASTERN COLORADO AND WESTERN KANSAS LATER THIS EVENING.
GIVEN LATE DAY INSTABILITY AND LOCATION OF LOW LEVEL FORCING AHEAD
OF THIS UPPER LEVEL TROUGH NEAR A SURFACE BOUNDARY THAT WILL
EXTEND FROM SOUTHEAST COLORADO INTO NORTH CENTRAL KANSAS THERE
WILL BE A CHANCE FOR SCATTERED THUNDERSTORMS LATE THIS AFTERNOON
ACROSS NORTH CENTRAL KANSAS AND PORTIONS OF WEST KANSAS. BASED ON
THE 21Z TUESDAY AND 00Z WEDNESDAY CAPE AND 0-6KM SHEAR FROM THE
NAM A FEW STORMS LATE TODAY MAY BE SEVERE WITH THE AREA MORE
FAVORABLE FOR HAIL GOLF BALL SIZE OR LARGER ALONG WITH WIND GUST
IN EXCESS OF 60 MPH WILL BE ALONG AND NORTH OF A DIGHTON AND
LARNED LINE.
THUNDERSTORMS WILL THEN INCREASE IN AREAL COVERAGE EARLY TONIGHT
AS THE UPPER LEVEL DISTURBANCE CROSSES THE CENTRAL HIGH PLAINS AND
A SURFACE BOUNDARY MOVES ACROSS SOUTHWEST KANSAS. THE AREA THAT
WILL BE MORE FAVORABLE FOR WIDESPREAD THUNDERSTORMS EARLY TONIGHT
WILL BE ALONG AND NORTH OF A 700MB +10C TO +13C BAROCLINIC ZONE.
GIVEN THE 12Z NAM AND 12Z GFS THIS FAVORABLE AREA WILL BE
NORTHEAST OF A SYRACUSE TO DODGE CITY THE PRATT LINE. ALSO GIVEN
THE HIGH PRECIPITABLE WATER VALUES PERIODS THERE WILL BE A CHANCE
FOR PERIODS OF HEAVY RAIN IN THIS AREA AS WELL.
BUFR SOUNDINGS INDICATING WINDS NEAR THE SURFACE BEHIND THE COLD
FRONT WILL RANGE FROM 20 TO 30 KNOTS AS THE LOWER LEVELS BEGIN TO
SATURATE. BY 12Z WEDNESDAY THE DEPTH OF THIS LOW LEVEL MOISTURE
APPROACHES 3000FT WHICH SUPPORTS INSERTING A SLIGHT CHANCE FOR
LIGHT DRIZZLE FOR SEVERAL HOURS EARLY WEDNESDAY MORNING. BY LATE
MORNING THIS LOW LEVEL MOISTURE WILL BEGIN TO ERODE FROM SOUTHWEST
NORTHEAST AND GIVEN SOME AFTERNOON SUNSHINE ACROSS SOUTHWEST AND
SOUTH CENTRAL KANSAS THE HIGHS ARE EXPECTED TO CLIMB BACK INTO THE
MID 70S BASED ON THE 00Z THURSDAY 850MB TEMPERATURES. FURTHER
NORTH, NEAR THE INTERSTATE 70 CORRIDOR THE CLOUDS AND 850MB
TEMPERATURES AT 00Z THURSDAY SUGGEST HIGHS ON IN THE UPPER 60S TO
NEAR 70.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 420 AM CDT TUE SEP 9 2014
ON WEDNESDAY, WE WILL BE BEHIND A COLD FRONT WITH MUCH COOLER
TEMPERATURES - GENERALLY IN THE 70S. ATTENTION THEN TURNS TO
THURSDAY AND FRIDAY. A REINFORCING SURGE OF CANADIAN AIR WILL MOVE
ACROSS THE REGION LATE THURSDAY. THE ECMWF IS QUITE CONSISTENT ON
THIS COLD AIR MASS. FRIDAY LOOKS PARTICULARLY COOL WITH RAIN,
CLOUDS, 20-25 MPH NORTHERLY WINDS, AND TEMPERATURES STRUGGLING TO
CLIMB OUT OF THE 50S. CONDITIONS WILL MODERATE THEREAFTER AS A LOW
LEVEL WARM AIR ADVECTION PATTTERN BECOMES ESTABLISHED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1208 PM CDT TUE SEP 9 2014
WIDELY SCATTERED THUNDERSTORMS WILL BE POSSIBLE AFTER 21Z ALONG
AND NORTH OF A GARDEN CITY TO HAYS LINE AS MID LEVEL MOISTURE AND
INSTABILITY INCREASES AHEAD OF AN UPPER LEVEL DISTURBANCE THAT
WILL BEGIN TO EXIT THE ROCKIES AND MOVE OUT INTO THE CENTRAL HIGH
PLAINS. THUNDERSTORMS WILL INCREASE IN AREAL COVERAGE EARLY
TONIGHT AS THIS UPPER LEVEL TROUGH CROSSES THE CENTRAL HIGH PLAINS
AND A SURFACE COLD FRONT CROSSES WESTERN KANSAS. AS THE COLD FRONT
PASSES THE CONVECTION WILL TAPER OFF, HOWEVER GUSTY NORTH WINDS AT
20 TO NEAR 25 KNOTS WILL DEVELOP BEHIND THIS FRONT ALONG WITH
INCREASING LOW LEVEL MOISTURE. BASED ON BUFR SOUNDINGS CEILINGS
BETWEEN 700 AND 1500FT AGL IS EXPECTED AFTER 09Z AT HAYS AND
BETWEEN 12Z AND 15Z AT GARDEN CITY AND DODGE CITY.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 63 73 49 65 / 40 10 0 10
GCK 62 73 49 63 / 50 20 10 10
EHA 62 75 52 69 / 20 10 10 10
LBL 64 76 51 67 / 20 10 0 10
HYS 62 68 45 62 / 70 20 0 10
P28 70 78 53 71 / 30 10 0 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...99
AVIATION...BURGERT
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1049 PM EDT WED SEP 10 2014
.UPDATE...
ISSUED AT 1049 PM EDT WED SEP 10 2014
HAVE SLOWED DOWN THE PRECIPITATION ONSET JUST A BIT MORE BASED ON THE
LATEST RADAR AND HRRR MODEL TRENDS. THE LATEST IR SATELLITE SHOWS
QUITE A BIT OF CLEARING ACROSS OUR AREA CURRENTLY...AND A FEW OF THE
NORMALLY COOLER VALLEYS HAVE ALREADY DIPPED INTO THE UPPER 60S.
CLOUDS SHOULD FILL IN NICELY BETWEEN 06 AND 12Z...HOWEVER DID LOWER
SOME OF THE LOW TEMPERATURES IN THE EAST WHERE SOME DECENT CLEARING
WILL HANG ON FOR THE NEXT 2 TO 3 HOURS...ALLOWING FOR ANOTHER DEGREE
DROP OFF OR SO. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 820 PM EDT WED SEP 10 2014
BASED ON OBS AND AFTERNOON MODEL RUNS...HAVE SLOWED THE ARRIVAL OF
PRECIP TONIGHT...BUT THE OVERNIGHT REMAINS UNCHANGED...WITH THE SAME
12 HOUR POPS FOR THE PERIOD.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 400 PM EDT WED SEP 10 2014
MODELS ARE IN GOOD AGREEMENT FOR THE WEATHER EVENT TO AFFECT US
DURING THE PERIOD. A COLD FRONT WILL MOVE SOUTHEAST...PASSING THROUGH
KY ON THURSDAY AND THURSDAY EVENING. SHOWERS WILL OCCUR NEAR AND
AHEAD OF THE FRONT...ENTERING THE JKL FORECAST AREA OVERNIGHT...WITH
MOST OF THE PRECIP EXITING INTO TN AND VA BY THURSDAY EVENING.
LIMITED HEATING IS EXPECTED ON THURSDAY AND LAPSE RATES WILL BE NEAR
MOIST ADIABATIC...AND WINDS ALOFT ONLY MODEST. SO...DESPITE AMPLE
MOISTURE...CONVECTION SHOULD NOT BE TOO RAMBUNCTIOUS. PRECIPITABLE
WATER WILL BE NEAR 2 INCHES...AND LOCALLY HEAVY RAINFALL MAY OCCUR
WHERE CELLS TRAIN...BUT THE CELLS WILL AT LEAST BE MOVING ALONG.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 400 PM EDT WED SEP 10 2014
ATTENTION TURNS TO A SIGNIFICANT SHORT WAVE THAT WILL MOVE FROM THE
NORTH PLAINS EAST TO THE GREAT LAKES FRIDAY INTO SATURDAY. THIS WAVE
MOVES PAST EAST KENTUCKY DURING THE DAY SATURDAY FOLLOWED BY
FLATTER...BUT STILL RATHER FAST...FLOW INTO THE DAY SUNDAY. FOR THIS
TIME FRAME...THROUGH THE DAY TUESDAY...WILL FAVOR A GENERAL MODEL
BLEND. THE MODELS KEEP THIS SORT OF ABNORMALLY COOL PATTERN GOING
THROUGH THEIR RUN SUGGESTING THAT OUR DAYS OF SUMMER-LIKE WEATHER MAY
BE OVER FOR THE SEASON...THOUGH BEING KENTUCKY IT WOULD NOT TAKE
MUCH OF A WIGGLE TO BRING SOME SOUTHERN WARMTH BACK NORTH. WE SHALL
SEE...
THE RUB WITH THE FORECAST THROUGH THE FIRST PART OF THE WEEKEND WILL
BE THE POSSIBILITY THAT THE FRONT DOES NOT COMPLETELY CLEAR THE CWA
AND LINGERS CLOSE ENOUGH FOR SHOWERS TO ACCOMPANY THE FALL-LIKE COOL
DOWN FOR OUR SOUTHERN MOST LOCATIONS. THE SHOWER THREAT INCREASES
DURING FRIDAY NIGHT THROUGH THE DAY SATURDAY AS A REINFORCING COLD
FRONT MOVES THROUGH THE OHIO VALLEY. THIS FRONT SHOULD HAVE A BETTER
PUSH BEHIND IT AND HELP TO CLEAR OUT LINGERING SHOWER THREATS FOR AT
LEAST A DAY OR SO ACROSS ALL OF THE AREA. THE HIGH PRESSURE
ASSOCIATED WITH THIS COOL BLAST WILL MODERATE SOMEWHAT AND MOVE BY TO
THE NORTHEAST BY MONDAY MORNING.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 820 PM EDT WED SEP 10 2014
VFR CONDITIONS PREVAILED EARLY THIS EVENING...AND SHOULD LAST
THROUGH MOST OF THE NIGHT. SHOWERS WILL BEGIN TO SHOW UP LATE
TONIGHT...ESPECIALLY NORTH OF INTERSTATE 64...AND THEN DEVELOP
SOUTHEASTWARD ON THURSDAY. AS THEY BECOME MORE PREVALENT...SO WILL
MVFR CONDITIONS ON THURSDAY. A FEW THUNDERSTORMS MAY ALSO OCCUR.
MUCH OF THE PRECIPITATION WILL BE ON THE DECLINE AND EXITING INTO VA
AND TN BY THE END OF THE PERIOD. BUT MVFR CEILINGS WILL LIKELY LINGER
IN MANY LOCATIONS UNTIL LATE IN THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...HAL
LONG TERM...JKL
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
856 PM CDT WED SEP 10 2014
.UPDATE...
...SOUNDING DISCUSSION...
THIS EVENINGS BALLOON LAUNCH WAS SUCCESSFUL WITH NO ISSUES OF
NOTE. ISOLATED AFTERNOON STORM DEVELOPMENT HAS REMAINED INTACT FOR
THE AREA WITH 2.02 INCHES PRECIPITABLE WATER AND CONVECTIVE TEMPS
AT 87F. PRIOR TO LAUNCH...THERE WAS CONVECTION TO THE NORTH OF
THE WFO THAT HAD MATURED AND DISSIPATED GIVING WAY TO A LAUNCH IN
MOSTLY CLEAR CONDITIONS. LOW TO MID LEVEL WINDS REMAIN LIGHT AND
VRBL WITH SOUTHERLY COMPONENT MIXED IN UP TO 19000 FT. FROM
21000FT UP TO TERMINATION AT 33771FT...THE SOUNDING CONTAINED NE-
ENE 20-40 KTS WINDS THAT HELPED PUSH THE BALLOON WELL TO THE WEST
OF THE WFO IN SLIDELL.
MGW
&&
.PREV DISCUSSION... /ISSUED 308 PM CDT WED SEP 10 2014/
SHORT TERM...
RATHER MOIST AIR MASS IN PLACE ON STEADY-STATE ONSHORE FLOW AROUND
PERIPHERY OF BERMUDA RIDGE. MID LEVELS HAVE WARMED TO LIMIT THE
DEPTH OF CONVECTIVE COVERAGE THROUGH AT LEAST 89F CONVECTIVE
TEMPERATURES...OVERCOMING 500 MB WARM LAYER AROUND 91F SURFACE
TEMPERATURE. RESULT WILL BE SHORT-LIVED SLOW-MOVING BUT EFFICIENT
SHOWERS AND BRIEF THUNDERSTORMS FORMING MAINLY ON OUTFLOW
INTERSECTIONS THAT ARE PROMINENTLY DISPLAYED ON RADAR
PRESENTATION. THIS CONVECTION SHOULD DISSIPATE SHORTLY AFTER
SUNSET. MEANWHILE...EASTERLY WAVE CURRENTLY TRAVERSING THE
NORTHEAST GULF UNDER THE RIDGE WILL SERVE AS A FOCUS FOR DEEPER
LOW LEVEL MOISTURE THURSDAY AND FRIDAY. THIS IS CONSISTENT WITH
THE WRF AND HRRR MODEL RUNS FOR THURSDAY AFTERNOON AS WELL AS THE
OTHER LONGER RANGE MODELS. WILL INDICATE HIGHER RAIN CHANCES
CLOSER TO THE COAST AND TAPER DOWNWARD FARTHER INLAND THURSDAY.
WITH FRONTAL ZONE SETTLING INTO THE AREA FRIDAY...WILL BE
DIFFICULT TO DISTINGUISH FAVORED AREAS FOR FOCUSED RAINFALL DUE TO
VARIOUS CAUSES/PROCESSES...SO WILL SIMPLY GO 50 PERCENT ENTIRE
AREA. IF DEEPER GULF MOISTURE ALIGNS IN CONVERGENT BANDS...THEN
SOME LOCATIONS MAY UNDERGO SOME SHORT DURATION OF TRAINING WHICH
MAY ACCUMULATE MORE RAINFALL...MOSTLY LIKELY CLOSER TO THE COAST
THOUGH FRONTAL ZONE MAY COMPLICATE MATTERS.
LONG TERM...
MODELS ALL AGREE IN STALLING THE FRONT ALONG OR CLOSE TO THE GULF
COAST SATURDAY AS UPPER SUPPORT SHUNTS EASTWARD. THIS DIFFERS FROM
MAN-MACHINE MIX THAT CONTINUES TO INDICATE A DEEPER FRONTAL
ADVANCE WELL INTO THE GULF BEFORE STALLING. ASSOCIATED CONVECTION
AND OUTFLOWS MAY INDUCE THE SURFACE FRONT SOUTHWARD BUT THE AIR
MASS WOULD BE GREATLY MODIFIED AND RUNNING MOSTLY ON RAIN COOLED
DENSITY. IN COORDINATION WITH SURROUNDING OFFICES...WE WILL BE
INDICATING WARMER THAN GUIDANCE TEMPERATURES FOR MORNING LOWS
SUNDAY AND MONDAY IN DEFERENCE TO NATIONAL GUIDANCE...PARTICULARLY
IF TROPICAL WAVE INFLUENCES BECOME INVOLVED THIS FAR SOUTH. WHILE
ON THE SUBJECT...THE NHC HAS HIGHLIGHTED A YELLOW OUTLOOK AREA
FROM THE BAHAMAS WESTWARD ACROSS THE NORTH GULF. THIS IS A
TROPICAL WAVE THAT SHOULD REMAIN OPEN WHILE TRAVERSING UNDER THE
UPPER RIDGE. SEVERAL MODELS INDICATE SUCH A SCENARIO...ONLY THE
CANADIAN RUN SHOWS A CLOSED LOW STRUCTURE THAT DOES NOT LOOK
ATTAINABLE GIVEN CURRENT PATTERN IN PLACE. NONETHELESS...THIS
FEATURE SHOULD SERVE TO BRING GREATER FOCUS FOR RAINFALL POTENTIAL
OVER THE WEEKEND...PARTICULARLY AS IT INTERACTS WITH ANY
STATIONARY FRONTAL FOCUS. RAINFALL POTENTIAL CAN BECOME PRONOUNCED
AND OF CONSIDERABLY LONG DURATION WHEREVER THE FRONT AND WAVE
INTERSECT. THE KEY IS WHETER IT WILL BE OFF THE COAST OR JUST
INLAND ENOUGH TO PRESENT A FLOOD THREAT FOR SOME COASTAL
COMMUNITIES. THIS WILL HAVE TO BE CLOSELY MONITORED OVER THE NEXT
FEW DAYS.
AVIATION...
VFR CONDITIONS TO PREVAIL THROUGH AT LEAST 09Z. SOME PATCHY
RADIATIONAL FOG MAY DEVELOP AT KMCB TOWARDS DAYBREAK THURSDAY THAT
MAY BRING BRIEF IFR CIGS/VSBY BUT MOST OTHER LOCATIONS SHOULD
REMAIN VFR OVERNIGHT. CONVECTION REMAINS ISOLATED IN COVEARAGE
THIS AFTERNOON AND SHORT-LIVED. GUST POTENTIAL IS AROUND 20 KT
RANGE REMAINDER OF THIS AFTERNOON AND PROJECTED 25-30 KT RANGE
THURSDAY.
MARINE...
BERMUDA RIDGE FLOW PATTERN SHOULD MAINTAIN RELATIVELY LIGHT WINDS
AND LOW SEAS FOR THURSDAY AND FRIDAY. A COLD FRONT MOVING FROM
THE NORTH IS LIKELY TO STALL BEFORE REACHING THE COAST LATE FRIDAY
OR EARLY SATURDAY. MEANWHILE...AN EASTERLY WAVE WILL BE TRAVERSING
THE NORTH GULF FRIDAY AND SATURDAY AND SHOULD INTERACT WITH THE
FRONTAL ZONE TO POTENTIALLY PRODUCE GREATER COVERAGE OF TROPICAL
SHOWERS AND THUNDERSTORMS IN THE NEAR COASTAL WATERS AND SOUNDS
THIS WEEKEND. SEAS SHOULD REMAIN LESS THAN 2 FEET THROUGH MONDAY
EVENING.
DECISION SUPPORT...
DSS CODE...GREEN.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT.
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TO HIGH RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE.
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 72 90 72 89 / 10 30 20 50
BTR 73 91 73 90 / 10 30 20 50
ASD 74 90 73 90 / 10 30 20 50
MSY 77 90 77 90 / 10 40 20 50
GPT 76 89 75 90 / 20 40 20 50
PQL 73 90 72 89 / 20 40 20 50
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
805 AM EDT TUE SEP 9 2014
.SYNOPSIS...
LOW PRESSURE OVER NORTHEAST NORTH CAROLINA WILL MOVE SLOWLY NORTHEAST
AND OFF THE VIRGINIA COAST TONIGHT. HIGH PRESSURE BUILDS OVER THE
MID ATLANTIC STATES WEDNESDAY. A COLD FRONT APPROACHES FROM THE
WEST THURSDAY AND CROSSES THE REGION BY EARLY FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 11Z...SURFACE ANALYSIS HAS LOW PRESSURE NEAR BERTIE COUNTY NC
WITH A FRONTAL BOUNDARY THROUGH HAMPTON ROADS AND THE MOUTH OF THE
CHESAPEAKE BAY. VERY HEAVY RAINFALL THAT WAS ASSOCIATED WITH A FLOOD
WARNING OVER MOST OF THE HAMPTON ROADS AREA HAS DIMINISHED
SIGNIFICANTLY AROUND 11Z. CURRENTLY ...RAIN WAS OVER THE LOWER
VIRGINIA EASTERN SHORE...SOME MODERATE TO HEAVY. AREAS OF RAIN WERE
ALSO OVER PORTIONS OF HAMPTON ROADS. RADAR ANIMATION SHOWED MID
LEVEL CIRCULATION OVER THE SOUTHERN CHESAPEAKE BAY. FLOOD WATCH
REMAIN IN EFFECT FOR HAMPTON ROADS AND THE LOWER VIRGINIA EASTERN
SHORE THROUGH 16Z.
POPS OVER THE CWA HAVE BEEN LOWERED BUT NOT AS MUCH AS CURRENT RADAR
TRENDS WOULD INDICATE. AREAS OF INTERSTATE 95 COULD STAY DRY BUT
STILL HAVE CHC POPS IN THIS AREA THROUGH MIDDAY. HRRR HAS REASONABLE
HANDLE AND THIS HAS ONLY SPOTTY LIGHT SHOWERS OVER THE CWA AFT 18Z.
AS THE LOW MOVES TO THE NORTHEAST INTO THE HAMPTON ROADS AREA...RAIN
WILL SPREAD INTO THE MD EASTERN SHORE.
OVERCAST CLOUDS WILL PREVAIL ACROSS THE AREA AND KNOCKED
TEMPERATURES A BIT FROM GUIDANCE. HIGHS RANGE FROM THE LOW TO MID
70S WELL INLAND TO THE UPR 70S AND NEAR 80 OVER SE VA AND NE NORTH
CAROLINA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
AS THE LOW PULLS OFF TO THE EAST...30-40 PERCENT POPS REMAIN NEAR
THE COAST AND OVER THE LOWER EASTERN SHORE THIS EVENING. LOW
TEMPERATURES RANGE FROM THE MID 60S TO NEAR 70. SLGT CHC POPS ON THE
LOWER EASTERN SHORE WEDNESDAY MORNING. THE SKY CLEARS SOMEWHAT AND
HIGH TEMPERATURES CLIMB TO THE MID 80S OVER INLAND AREAS WEDNESDAY
(AROUND 80 NEAR THE COAST).
ON THU...A WEAKENING FRONT IS FORECAST TO REACH THE CNTRL
APPALACHIANS BY LATE THURS. UPPER FLOW WILL FLATTEN...BECOMING
MORE WLY OVER THE LOCAL AREA. LEADING SHORTWAVE IS PROGGED TO LIFT
WELL TO THE NORTH OF THE REGION THURS...LEAVING LITTLE APPRECIABLE
FORCING FOR THE LOCAL AREA. HOWEVER...INCREASING MOISTURE AND
THETA-E ADVECTION WILL RESULT IN CHANCE POPS FROM THE PIEDMONT INTO
CNTRL VA BY AFTN. KEPT EASTERN PORTIONS OF THE AREA DRY THROUGH THE
DAYTIME HOURS. WARM THURS AS HEIGHTS/THICKNESSES RISE. H85 TEMPS
ALSO REACH +18C. EXPECT HIGHS AROUND 90 TO THE LWR 90S WITH MID TO
UPR 80S TOWARD THE COAST.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
MODELS STILL AGREE THAT A COLD FRONT WILL CROSS THE REGION LATE
THURS NIGHT INTO FRI MORNING...USHERING IN A MUCH COOLER AIR BY
THE WEEKEND.
MEDIUM RANGE GUIDANCE CONTINUES TO PERFORM RELATIVELY WELL THROUGH
THE PERIOD WITH SOME DIFFERENCES REGARDING WHERE THE FRONT STALLS.
THIS IS RESULTING IN SOME MODEL DIFFERENCES REGARDING THE AMOUNT OF
MOISTURE THIS WEEKEND. COLD FRONT DROPS INTO THE AREA THURS
NIGHT-FRI MORNING...AND OFFSHORE FRI AFTERNOON. WILL CARRY LOW END
CHANCE POPS AS THE FRONT DROPS THRU THURS NIGHT. HOWEVER...UPPER
LEVEL SUPPORT IS RATHER UNIMPRESSIVE AS BEST DYNAMICS/HEIGHT FALLS
REMAIN WELL TO THE NORTH. BEST POPS TRANSITION TO THE COAST FRI
AFTERNOON AS THE FRONT PUSHES OFFSHORE AND SLOWS. TRENDED HIGHS
DOWN A FEW DEGS FRI...BUT HIGHS STILL PROGGED IN THE LOW-MID 80S
AS BEST CAA ARRIVES FRI NIGHT. UPPER TROUGH QUICKLY PUSHES
OFFSHORE SAT IN PROGRESSIVE FLOW...ALLOWING COOL CANADIAN HIGH
PRESSURE TO QUICKLY BUILD IN FROM THE WEST SAT-SAT NIGHT. SFC HIGH
WILL USHER IN MUCH COOLER/DRIER CONDITIONS FOR THE WEEKEND. HIGHS
GENERALLY IN THE MID-UPPER 70S (AROUND -1 STD DEV) WITH LOWS IN
THE UPPER 50S-LOWER 60S.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
LOW PRESSURE OVER NORTHEAST NORTH CAROLINA WILL MOVE VERY SLOWLY
NORTHEAST...MOVING OFF THE COAST VIRGINIA COAST TONIGHT. RAIN WILL
DIMINISH FROM WEST TO EAST TODAY BUT LOW CLOUDS WILL CONTINUE TO
AFFECT THE TAF SITES THROUGH MUCH OF THE 12Z TAF PERIOD. MOS
INDICATES IFR CIGS MAY REDEVELOPING AT MOST OF THE TAF SITES
TONIGHT.
OUTLOOK...THE LOW MOVES OUT TO SEA WEDNESDAY WITH DRIER AIR BEING
PULLED INTO THE AREA FROM THE NW. A COLD FRONT APPROACHES THE AREA
THURSDAY NIGHT BRINGING A CHC FOR TSTMS THURSDAY NIGHT AND FRIDAY.
PCPN CHANCES CONTINUE INTO SATURDAY AS UNSETTLED CONDITIONS ARE
EXPECTED TO REMAIN NORTH OF THE FRONT. PERIODS OF MVFR OR IFR WILL
BE PSBL THURSDAY NIGHT THROUGH SATURDAY.
&&
.MARINE...
LATEST OBS INDICATING E-NE WINDS ACROSS THE MARINE AREA THIS
MORNING. SEA 4 TO 6 FT SEAS OVER THE SOUTHERN WATERS THIS
MORNING...AND IN THE 6-8FT RANGE NORTH OF PARRAMORE. GOOD MODEL
AGREEMENT ATTM IN TRACKING SFC LOW PRESSURE SLOWLY ACROSS THE
COASTAL PLAIN THROUGH THIS EVENING...WITH WINDS SLOWLY BECOMING
SSE BY AFTN AND THIS EVENING. WL ADD SOUTHERN WATERS TO SCA WITH
SEAS OUT NEAR 20NM LIKELY REMAINING IN SCA THROUGH THE DAY AS PER
THE LATEST NWPS. AS THE LOW MOVES OFFSHORE TONIGHT, WINDS BRIEFLY
BACK TO THE NORTH OVER THE BAY AND MUCH OF THE COASTAL
WATERS TONIGHT, DIMINISHING LATE AND BECOMING NE AS SYSTEM EXITS
TO THE NORTHEAST.
SCA NOW IN PLACE FOR THE LOWER JAMES THROUGH MIDDAY...THE BAY
THROUGH LATE TONIGHT. SCA SLOWLY DROP OFF FROM SOUTH TO NORTH THIS
EVENING THROUGH WED AFTERNOON. HOWEVER, WILL NEED TO WATCH SEAS
LINGERING AROUND 5 FEET OVER NRN WATERS IN THE WAKE OF THE SYSTEM.
IN THAT EVENT, SCA MAY NEED TO BE EXTENDED FARTHER INTO WED NGT
PER LATEST WAVEWATCH. RESIDUAL MORE BENIGN MARINE CONDS EXPECTED
BY MID TO LATE WEEK AS A COLD FRONT APPROACHES FROM THE WEST,
SCOURING OUT LLVL WEDGE BY LATER WED AS LOW PRESSURE PUSHES
FARTHER OFFSHORE. SUB-SCA SSW FLOW DEVELOPS THU/THU NGT AHEAD OF
A STRONG COLD FRONT, WHICH DROPS ACROSS THE WATERS EARLY ON FRI.
ANOTHER PERIOD OF SCA CONDITIONS POSSIBLE FRI/FRI NGT. COOL/DRY
CONDITIONS EXPECTED THRU THE WEEKEND.
&&
.TIDES/COASTAL FLOODING...
NE FLOW 15-25 KT WILL PERSIST THROUGH TONIGHT, RESULTING IN
BUILDING TIDAL ANOMALIES CONTINUING 1 TO 1.5 FT ABOVE NORMAL
FOR THE NEXT 2 HIGH TIDE CYCLES THIS MORNING AND AGAIN THIS
EVENING. ANOTHER ROUND OF COASTAL FLOOD ADVYS HAVE BEEN ISSUED FOR
THE NEXT TIDE CYCLE ACROSS HAMPTON ROADS AND TIDEWATER AREAS AND
COVERING THE NEXT 2 TIDE CYCLES OVER ATLANTIC COASTAL SECTIONS OF
THE MD EASTERN SHORE.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...BEACH HAZARDS STATEMENT UNTIL 8 PM EDT THIS EVENING FOR MDZ025.
COASTAL FLOOD ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR MDZ025.
COASTAL FLOOD ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR
MDZ023.
NC...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
NCZ102.
VA...FLOOD WATCH UNTIL NOON EDT TODAY FOR VAZ086-091-093>100.
COASTAL FLOOD ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR
VAZ091-093>098.
MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
VAZ098.
BEACH HAZARDS STATEMENT UNTIL 8 PM EDT THIS EVENING FOR VAZ099-
100.
COASTAL FLOOD ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR VAZ099.
COASTAL FLOOD ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR
VAZ077-078-084>086.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 AM EDT WEDNESDAY FOR ANZ654-656.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT WEDNESDAY FOR ANZ650-652.
SMALL CRAFT ADVISORY UNTIL 6 AM EDT WEDNESDAY FOR ANZ630>632-
634.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ633-
658.
SMALL CRAFT ADVISORY UNTIL 1 PM EDT THIS AFTERNOON FOR ANZ638.
&&
$$
SYNOPSIS...LSA
NEAR TERM...LSA
SHORT TERM...LSA
LONG TERM...SAM/JAO
AVIATION...LSA
MARINE...MAM
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
347 PM EDT TUE SEP 9 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 344 PM EDT TUE SEP 9 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A SPLIT FLOW PATTERN WITH A
DEVELOPING MID/UPPER LEVEL TROUGH OVER THE WRN CONUS. THE TAIL OF AN
ELONGATED SHORTWAVE TROUGH MOVING THROUGH NRN ONTARIO WAS DRAGGING A
COLD FRONT SLOWLY SOUTH INTO WRN LAKE SUPERIOR. A VIGOROUS SRN
STREAM SHRTWV MOVING IN THE CNTRL PLAINS WILL SUPPORT DEVELOPMENT OF
A SFC LOW THAT WILL MOVE INTO THE WRN LAKES WED. EVEN WITH LAKE
BREEZE ONSHORE WINDS INTO WRN UPPER MI...LOW LEVEL CONV HAS NOT BEEN
STRONG ENOUGH TO OVERCOME CAPPING WITH 800-750 MB TEMPS NEAR
12C...PER RUC. OTHERWISE...ABUNDANT CU PREVAILED ACROSS THE WEST
HALF OF UPPER MI WHILE MORE STABLE AIR OFF OF LAKE MI HAS KEPT SKIES
MOSTLY CLEAR OVER THE EAST.
THE POTENTIAL REMAINS FOR SOME SHRA/TSRA THIS EVENING AS THE FRONTAL
BOUNDARY MOVES THROUGH WRN UPPER MI. HOWEVER...COVERAGE SHOULD
LIMITED WITH ONLY LOWER END CHANCE POPS GIVEN THE STRENGTH OF THE
CAPPING.
AS THE PLAINS SHRTWV MOVES TOWARD THE AREA AND THE SFC LOW
DEEPENS...300-310 ISENTROPIC ASCENT ALONG WITH 800-600 MB FGEN WILL
STRENGTHEN AND SUPPORT AN EXPANDING AREA OF MODERATE TO HEAVY RAIN
FROM NW/N WI INTO WRN UPPER MI BY LATE EVENING AND INTO CNTRL UPPER
MI LATE TONIGHT. STRONG MID/UPPER LEVEL DYNAMICS WITH A COUPLED
UPPER LEVEL JET STRUCTURE AND STRONG QVECTOR CONV WILL SUPPORT A
LARGE AREA OF RAIN ACROSS THE CWA WED. SOME MODEL UNCERTAINTY
REMAINS AS THE NAM REMAINS MUCH DEEPER AND FARTHER TO THE NW THAN
MODELS CONSENSUS AND THE GFS FASTER AND ALONG THE SOUTHERN ENVELOPE
OF MODEL SPREAD. FAVORED THE MORE CONSISTENT ECMWF AND REGIONAL GEM
WITH THE LOW PATH TO NEAR GRB BY 18Z AND THE STRAITS BY 00Z/THU.
VERY STRONG 850 MB MOISTURE INFLOW...UPPER LEVEL AND 800-600 MB FGEN
EVEN WITHOUT TSRA WILL BRING THE POTENTIAL FOR A PERIOD OF HEAVY
RAIN...ESPECIALLY BTWN 09Z-18Z. UNCERTAINTY REMAINS ON THE IMPACT OF
UPSTREAM CONVECTION OVER IA INTO SRN WI ON THE EVOLUTION OF THE
850-700 MB FRONTAL BOUNDARY AND MOISTURE INFLOW TO THE NORTH.
HOWEVER...THE POTENTIAL REMAINS FOR QPF IN THE 1.5 INCH TO 2.0 INCH
RANGE...WITH LOCALLY HIGHER AMOUNTS AOA 3 INCHES. SO THE FLOOD WATCH
WILL REMAINS IN EFFECT.
NE WINDS VEERING TO THE NNE WILL ALSO INCREASE WITH GUSTS LIKELY IN
INTO THE 40-50 KNOT RANGE BY TO LATE AFTERNOON OVER THE
KEWEENAW...ESPECIALLY FOR LOCATIONS FAVORED BY NNE FLOW SUCH AS
COPPER HARBOR. AN ADVISORY WILL LIKELY BE NEEDED.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 305 PM EDT TUE SEP 9 2014
SOME DISCREPANCIES BETWEEN MODELS AT 00Z THU. TWO EXTREMES WITH THE
LOW LOCATION/STRENGTH ARE THE 12Z/09 GFS WITH A 997MB SFC LOW NEAR
CENTRAL LAKE HURON AND THE 12Z/09 NAM WITH A 984MB SFC LOW NEAR
MUNISING. HARD TO JUMP ON BOARD WITH EITHER OF THESE TWO EXTREMES
GIVEN WARM SEASON PROCESSES THAT WILL OCCUR IN THE WARM SECTOR OF
THE LOW...BUT THINK A MIDDLE OF THE GROUND APPROACH IS MORE
REASONABLE. REGARDLESS...STRONG NLY WINDS WILL BE ONGOING ACROSS THE
CWA AT 00Z THU...AND IF THE FARTHER N/STRONGER SOLUTION IS
CORRECT...THE WINDS WOULD BE VERY STRONG. THE HIGH EXTREME OF THE
NAM EVEN HAS 925MB WINDS UP TO 70KTS /POSSIBLY RESULTING IN SFC
GUSTS OF 55-70KTS/ BETWEEN 00Z AND 06Z THU...WHICH CAN NOT BE RULED
OUT...BUT MORE MODERATE WINDS ARE EXPECTED. BY 06Z...EVEN THE NAM
HAS THE LOW E OF LAKE SUPERIOR...WITH OTHER MODELS FARTHER SE. BY
12Z THU...925MB WINDS ARE EXPECTED TO BE BELOW 30KTS...WITH THE
PRESSURE GRADIENT RELAXING FASTER DURING THE DAY THU. MOST OF THE
PRECIP WED NIGHT INTO THU WILL BE DUE TO WRAP AROUND MOISTURE AND
UPSLOPE FLOW AND SHOULD GRADUALLY DIMINISH INTO THU EVENING.
THU LOOKS TO BE COLDEST DAY IN A WHILE AREA WIDE AS CLOUDY
CONDITIONS PERSIST BEHIND THE SYSTEM AND 850MB TEMPS WILL BE -2C TO
1C...RESULTING IN HIGH TEMPS FROM THE UPPER 40S INTERIOR W TO THE
LOW 50S ELSEWHERE...AND THE CONTINUED BREEZY WINDS WILL ONLY MAKE IT
FEEL COOLER.
GIVEN THE COLD TEMPS...THINK BELOW FREEZING MIN TEMPS THU NIGHT LOOK
FAIRLY LIKELY OVER THE INTERIOR W...WITH A MORE CONDITIONAL CHANCE
FRI NIGHT DEPENDING ON THE CLOUD COVER.
NOT SURE ABOUT PRECIP CHANCES FRI INTO FRI INTO SAT AS MODELS POINT
TO AN UPPER LEVEL DISTURBANCE MOVING INTO THE REGION OVER SFC HIGH
PRESSURE. ONLY LOW END POPS WILL REMAIN IN THE FORECAST AS THE ECMWF
IS THE ONLY MODEL SHOWING SIGNIFICANT PRECIP ACROSS THE CWA...THE
OTHER MODELS HAVE A WEAKER WAVE AND LESS MOISTURE. 850MB TEMPS
REMAIN MOSTLY THE SAME THROUGH SAT AT AROUND 0C...BUT CLOUD COVER
SHOULD BE LOWER EACH FRI AND ESPECIALLY SAT...SO HIGHS WILL WARM
INTO THE MID TO UPPER 50S BE SAT.
POSSIBILITY OF ANOTHER WAVE ON SUN AND MAYBE YET ANOTHER ON MON AS A
RIDGE BUILDS ACROSS THE WRN CONUS AND A TROUGH ACROSS THE ERN CONUS.
EVEN LOWER CONFIDENCE ON PRECIP WITH THESE FEATURES AS MOISTURE WILL
BE LIMITED AS THE TRACK/STRENGTH OF THE ENERGY IS UNCERTAIN. TEMPS
DO LOOK TO INCREASE BUT WILL REMAIN BELOW NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 132 PM EDT TUE SEP 9 2014
A COLD FRONT IS EXPECTED TO MOVE THROUGH IWD/CMX DURING THE
AFTERNOON...AND A WIND SHIFT TO THE NNE WITH THE ARRIVAL OF SOME
SHALLOW COOL AIR OFF LAKE SUPERIOR COULD BRING SOME MVFR CLDS INTO THOSE
LOCATIONS DURING THE AFTERNOON. THERE COULD BE A -SHRA OR PERHAPS
EVEN TS AT MAINLY IWD WITH THE ARRIVAL OF THE FRONT DURING PEAK
HEATING...BUT CONFIDENCE IS TOO LOW TO INCLUDE A SPECIFIC MENTION. AS
A STRONGER DISTURBANCE MOVES NEWD AND THE MOIST LYR DEEPENS...RAIN
WILL DEVELOP FROM SW TO NE AND CAUSE CONDITIONS AT IWD/CMX TO DROP TO
IFR BY LATE EVENING. SINCE THE FROPA WILL OCCUR LATER AT SAW...THE
TRANSITION TO MVFR WILL NOT OCCUR UNTIL LATER IN THE FCST PERIOD. BY
LATE TONIGHT INTO WED MORNING LIFR CONDITIONS WILL PREVAIL WITH
MODERATE TO OCNLY HEAVY RAIN.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 344 PM EDT TUE SEP 9 2014
THE TROUGH STRETCHED ACROSS W LAKE SUPERIOR WILL DRIFT ACROSS LAKE
SUPERIOR THIS EVENING AS LOW PRESSURE APPROACHES FROM THE CENTRAL
PLAINS. THE LOW WILL BE OVER E IOWA BY DAYBREAK WEDNESDAY...AND
CONTINUE TO PUSH TO NRN LOWER MI BY WED EVENING...BEFORE EXITING
INTO QUEBEC ON THURSDAY. NORTHEAST GALES TO AROUND 40KTS WILL BE
POSSIBLE WEDNESDAY MORNING OVER W LAKE SUPERIOR...BEFORE SLOWLY
EXPANDING TO CENTRAL LAKE SUPERIOR WEDNESDAY EVENING THROUGH THE
OVERNIGHT HOURS AS WINDS BACK TO THE NORTH. LARGE HIGH PRESSURE OVER
S ALBERTA AND SASKATCHEWAN THURSDAY WILL SINK ACROSS THE N AND
CENTRAL PLAINS...WHILE BUILDING A RIDGE ACROSS LAKE SUPERIOR
THURSDAY NIGHT THROUGH SATURDAY WITH WINDS GUSTING TO AROUND 20KTS
OR LESS.
&&
.HYDROLOGY...
ISSUED AT 344 PM EDT TUE SEP 9 2014
RAINFALL TOTALS FROM TONIGHT THROUGH WEDNESDAY NIGHT ACROSS UPPER MI
RANGE FROM JUST OVER 1.5 TO LOCALLY 3 INCHES. UNCERTAINTY REMAINS
WHERE THE HEAVIER BANDS OF RAIN WILL DEVELOP. HIGHER TOTALS INTO WED
NIGHT ARE EXPECTED FOR LOCATIONS IN N CNTRL UPPER MI WHERE STRONG
UPSLOPE FLOW WILL BOOST RAINFALL AMOUNTS. THE FLOOD WATCH REMAINS
POSTED FOR MUCH OF W AND CENTRAL UPPER MI.
EXPECT THE TRADITIONAL URBAN/SMALL STREAM FLOODING TO BE A
SIGNIFICANT POSSIBILITY IN THE TYPICAL POOR DRAINAGE AREAS OF ESC IF
A PERIOD OF HEAVIER DOWNPOURS DEVELOP WITH RAINFALL RATES CLOSE TO
AN 0.5-1.0 INCH PER HOUR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FLOOD WATCH FROM 2 AM EDT /1 AM CDT/ WEDNESDAY THROUGH WEDNESDAY
EVENING FOR MIZ001>006-009>013-084.
LAKE SUPERIOR...
GALE WARNING FROM 8 PM WEDNESDAY TO 8 AM EDT THURSDAY FOR LSZ251-
267.
GALE WARNING FROM 2 PM WEDNESDAY TO 5 AM EDT THURSDAY FOR
LSZ246>250-265-266.
GALE WARNING FROM 8 AM WEDNESDAY TO 4 AM EDT THURSDAY FOR
LSZ243>245-264.
GALE WARNING FROM 5 AM EDT /4 AM CDT/ WEDNESDAY TO 2 AM EDT /1
AM CDT/ THURSDAY FOR LSZ240>242-263.
GALE WARNING FROM 5 AM EDT /4 AM CDT/ TO 11 PM EDT /10 PM CDT/
WEDNESDAY FOR LSZ162.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...JLB
MARINE...JLB
HYDROLOGY...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
315 PM EDT TUE SEP 9 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 438 AM EDT TUE SEP 9 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A WSW SPLIT FLOW
RUNNING ALONG THE CNDN BORDER. A SHRTWV WITHIN THE SRN BRANCH OVER
THE CONUS IS OVER NRN LK MI EARLY THIS MRNG AND WAS RESPONSIBLE FOR
SOME SPRINKLES THAT IMPACTED MAINLY THE SRN CWA SINCE YDAY AFTN. THE
ARRIVAL OF SOME SHRTWV RDGING/DEEP LYR QVECTOR DVGC/MID LVL DRYING
BEHIND THIS DISTURBANCE HAS ENDED THESE SPRINKLES...BUT AN AREA OF
SCT-BKN SC...RELATED TO H85 THETA E ADVCTN IN THE SW FLOW BTWN HI
PRES OVER NEW ENGLAND AND A COLD FNT SLIDING SEWD THRU NW ONTARIO/NW
MN...IS MOVING INTO THE WRN CWA. THE COLD FNT TO THE NW IS ATTENDANT
TO A SHRTWV NEAR JAMES BAY THAT IS LIFTING ENEWD WITHIN THE STRONGER
NRN BRANCH FLOW DOMINATING CANADA. SOME SHOWERS/TS ALONG THIS BNDRY
EXTENDED AS FAR AS ABOUT THE MN/ONTARIO BORDER...WHERE THE 00Z INL
RAOB SHOWS AN INVRN ARND H75 THAT IS SUFFICIENT TO CAP ANY
CONVECTION. THIS INVRN IS EVEN SHARPER ON THE MPX RAOB...
STRENGTHENED BY THE DEEP LYR QVECTOR DVGC IN THE WAKE OF SRN BRANCH
SHRTWV. LOOKING FARTHER UPSTREAM...THERE IS ANOTHER STRONGER SRN
BRANCH SHRTWV MOVING THRU NEVADA.
MAIN FCST CONCERN FOR TDAY IS WHETHER ANY SHOWERS/TS WL DVLP OVER
MAINLY WRN UPR MI AHEAD OF THE APRCHG COLD FNT FM THE NW. FOCUS FOR
TNGT WL SHIFT TO HOW QUICKLY LARGER AREA OF RA WL ARRIVE FM THE SW
IN ADVANCE OF SHRTWV NOW MOVING THRU THE CENTRAL ROCKIES.
TODAY...WHILE NRN BRANCH SHRTWV NEAR JAMES BAY WL CONTINUE ENEWD
INTO NRN QUEBEC...ATTENDANT COLD FNT IS FCST TO DROP SEWD INTO WRN
UPR MI THIS AFTN BUT THEN SLOW DOWN AS THE H5 FLOW BACKS SW/MORE
PARALLEL WITH THE FNT IN ADVANCE OF ROCKIES SHRTWV MOVING OUT INTO
THE CENTRAL PLAINS. WHILE THE SLOWING FNT MAY BE THE FOCUS FOR SOME
SHOWERS/TS IN THE PRESENCE OF DAYTIME HEATING...MODELS SHOW BULK OF
THE DEEP LYR QVECTOR CNVGC REMAINING TO THE N OF THE CWA CLOSER TO
LOW HGTS IN ONTARIO. IN THE ABSENCE OF THIS STRONGER LARGER SCALE
FORCING...SUSPECT MID LVL INVRN SHOWN ON THE UPSTREAM 00Z INL/MPX
RAOBS WL PERSIST IN LINE WITH THE GFS FCST SDNGS SHOWING LINGERING
INVRN ARND H75-8 AND LIMIT THE POTENTIAL FOR CONVECTION. SO WL
RETAIN GOING ONLY SCHC POPS OVER MAINLY THE W HALF FOR THE AFTN.
COMBINATION OF INCRSG H85 THETA E OVER THE FAR W TOWARD 00Z AND
ARRIVAL OF STRONGER FORCING IN ADVANCE OF APRCHG SHRTWV FM THE
PLAINS JUSTIFY INCRSG POPS OVER THE FAR W CLOSER TO THAT TIME AS GFS
FCST SDNG FOR IWD SHOWS WEAKENING INVRN TOWARD 00Z. AS FOR TEMPS...A
GOOD DEAL OF SC THAT WL FORM IN THE INCRSGLY MOIST S FLOW AHEAD OF
THE APRCHG FNT AND UNDER INVRN AS WELL AS FLOW OFF LK MI AS SFC
WINDS TEND TO BACK TOWARD THE SSE THRU THE DAY WL LIMIT THE RISE OF
THE MERCURY DESPITE WARM START TO THE DAY. TEMPS OVER THE W ARE
LIKELY TO FALL FOLLOWING PASSAGE OF THE SFC COLD FNT THIS AFTN AND
ARRIVAL OF SHALLOW COOL AIR.
TNGT...SHRTWV IN THE CENTRAL PLAINS WL MOVE NE...WITH FAIRLY DEEP
SFC LO ARND 996MB REACHING FAR NE IOWA TOWARD 12Z WED. ARRIVAL OF
SHARPER DEEP LYR QVECTOR CNVGC AND UPR DVGC IN ADVANCE OF THIS
DISTURBANCE AND OVER AXIS OF HIER H85 THETA E/PWAT AT LEAST NEAR
1.5 INCH WL BRING INCRSG POPS TO CATEGORICAL SW-NE...EXCEPT OVER THE
FAR E WHERE THE MORE IMPRESSIVE DYNAMICS WL NOT ARRIVE UNTIL AFTER
12Z WED. ALTHOUGH THIS SYNOPTIC SETUP FAVORS SOME HEAVY RA
ESPECIALLY OVER THE W HALF OVERNGT...THERE ARE A FEW LINGERING
QUESTION MARKS. THE FAVORED 00Z GFS MODEL INDICATES A BAND OF
SHARPER H85-7 FGEN WL SETUP ACRS CENTRAL WI OVERNGT...DISRUPTING
MSTR INFLOW INTO UPR MI. THE 00Z GFS GENERATES NO MORE THAN ABOUT
0.25-0.33 INCH OF RA THRU 12Z. SEVERAL OF THE HIER RES MODELS...
INCLUDING THE 00Z LOCAL WRF-ARW...GENERATE ONLY MINIMAL QPF OVER UPR
MI THRU 12Z WED. THE 00Z CNDN MODEL FOCUSES ITS HEAVIER PCPN TO THE
S OF THE CWA...CLOSER TO THAT AXIS OF FGEN SHOWN BY THE GFS. BUT
SINCE THE 00Z NAM...WHICH SHOWS A FARTHER NW TRACK FOR THE SFC LO
AND STRONGER SLY FLOW TO BRING HIER PWAT INTO THE CWA...AND THE 00Z
ECMWF DO PRODUCE GENEROUS RA OVER MAINLY THE W HALF...MADE NO CHG TO
GOING FLOOD WATCH FOR THE 06Z-12Z TIME. OTRW...THE SLOW MOVING COLD
FNT IS FCST TO SLIP ONLY SLOWLY SE THRU THE NGT...SO THE WARMEST
OVERNGT LO TEMPS WL BE OVER THE SE CWA.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 305 PM EDT TUE SEP 9 2014
SOME DISCREPANCIES BETWEEN MODELS AT 00Z THU. TWO EXTREMES WITH THE
LOW LOCATION/STRENGTH ARE THE 12Z/09 GFS WITH A 997MB SFC LOW NEAR
CENTRAL LAKE HURON AND THE 12Z/09 NAM WITH A 984MB SFC LOW NEAR
MUNISING. HARD TO JUMP ON BOARD WITH EITHER OF THESE TWO EXTREMES
GIVEN WARM SEASON PROCESSES THAT WILL OCCUR IN THE WARM SECTOR OF
THE LOW...BUT THINK A MIDDLE OF THE GROUND APPROACH IS MORE
REASONABLE. REGARDLESS...STRONG NLY WINDS WILL BE ONGOING ACROSS THE
CWA AT 00Z THU...AND IF THE FARTHER N/STRONGER SOLUTION IS
CORRECT...THE WINDS WOULD BE VERY STRONG. THE HIGH EXTREME OF THE
NAM EVEN HAS 925MB WINDS UP TO 70KTS /POSSIBLY RESULTING IN SFC
GUSTS OF 55-70KTS/ BETWEEN 00Z AND 06Z THU...WHICH CAN NOT BE RULED
OUT...BUT MORE MODERATE WINDS ARE EXPECTED. BY 06Z...EVEN THE NAM
HAS THE LOW E OF LAKE SUPERIOR...WITH OTHER MODELS FARTHER SE. BY
12Z THU...925MB WINDS ARE EXPECTED TO BE BELOW 30KTS...WITH THE
PRESSURE GRADIENT RELAXING FASTER DURING THE DAY THU. MOST OF THE
PRECIP WED NIGHT INTO THU WILL BE DUE TO WRAP AROUND MOISTURE AND
UPSLOPE FLOW AND SHOULD GRADUALLY DIMINISH INTO THU EVENING.
THU LOOKS TO BE COLDEST DAY IN A WHILE AREA WIDE AS CLOUDY
CONDITIONS PERSIST BEHIND THE SYSTEM AND 850MB TEMPS WILL BE -2C TO
1C...RESULTING IN HIGH TEMPS FROM THE UPPER 40S INTERIOR W TO THE
LOW 50S ELSEWHERE...AND THE CONTINUED BREEZY WINDS WILL ONLY MAKE IT
FEEL COOLER.
GIVEN THE COLD TEMPS...THINK BELOW FREEZING MIN TEMPS THU NIGHT LOOK
FAIRLY LIKELY OVER THE INTERIOR W...WITH A MORE CONDITIONAL CHANCE
FRI NIGHT DEPENDING ON THE CLOUD COVER.
NOT SURE ABOUT PRECIP CHANCES FRI INTO FRI INTO SAT AS MODELS POINT
TO AN UPPER LEVEL DISTURBANCE MOVING INTO THE REGION OVER SFC HIGH
PRESSURE. ONLY LOW END POPS WILL REMAIN IN THE FORECAST AS THE ECMWF
IS THE ONLY MODEL SHOWING SIGNIFICANT PRECIP ACROSS THE CWA...THE
OTHER MODELS HAVE A WEAKER WAVE AND LESS MOISTURE. 850MB TEMPS
REMAIN MOSTLY THE SAME THROUGH SAT AT AROUND 0C...BUT CLOUD COVER
SHOULD BE LOWER EACH FRI AND ESPECIALLY SAT...SO HIGHS WILL WARM
INTO THE MID TO UPPER 50S BE SAT.
POSSIBILITY OF ANOTHER WAVE ON SUN AND MAYBE YET ANOTHER ON MON AS A
RIDGE BUILDS ACROSS THE WRN CONUS AND A TROUGH ACROSS THE ERN CONUS.
EVEN LOWER CONFIDENCE ON PRECIP WITH THESE FEATURES AS MOISTURE WILL
BE LIMITED AS THE TRACK/STRENGTH OF THE ENERGY IS UNCERTAIN. TEMPS
DO LOOK TO INCREASE BUT WILL REMAIN BELOW NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 132 PM EDT TUE SEP 9 2014
A COLD FRONT IS EXPECTED TO MOVE THROUGH IWD/CMX DURING THE
AFTERNOON...AND A WIND SHIFT TO THE NNE WITH THE ARRIVAL OF SOME
SHALLOW COOL AIR OFF LAKE SUPERIOR COULD BRING SOME MVFR CLDS INTO THOSE
LOCATIONS DURING THE AFTERNOON. THERE COULD BE A -SHRA OR PERHAPS
EVEN TS AT MAINLY IWD WITH THE ARRIVAL OF THE FRONT DURING PEAK
HEATING...BUT CONFIDENCE IS TOO LOW TO INCLUDE A SPECIFIC MENTION. AS
A STRONGER DISTURBANCE MOVES NEWD AND THE MOIST LYR DEEPENS...RAIN
WILL DEVELOP FROM SW TO NE AND CAUSE CONDITIONS AT IWD/CMX TO DROP TO
IFR BY LATE EVENING. SINCE THE FROPA WILL OCCUR LATER AT SAW...THE
TRANSITION TO MVFR WILL NOT OCCUR UNTIL LATER IN THE FCST PERIOD. BY
LATE TONIGHT INTO WED MORNING LIFR CONDITIONS WILL PREVAIL WITH
MODERATE TO OCNLY HEAVY RAIN.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 359 AM EDT TUE SEP 9 2014
THE TROUGH STRETCHED ACROSS W LAKE SUPERIOR WILL DRIFT ACROSS LAKE
SUPERIOR TODAY AS LOW PRESSURE NEARS FROM THE CENTRAL PLAINS. THE
LOW WILL BE OVER E IOWA BY DAYBREAK WEDNESDAY...AND CONTINUE TO PUSH
NE OVER E UPPER MI AND N LOWER MI LATE WEDNESDAY AFTERNOON...BEFORE
EXITING INTO QUEBEC ON THURSDAY. N GALES TO AROUND 40KTS WILL BE
POSSIBLE WEDNESDAY MORNING OVER W LAKE SUPERIOR...BEFORE SLOWLY
EXPANDING TO CENTRAL LAKE SUPERIOR WEDNESDAY EVENING THROUGH THE
OVERNIGHT HOURS. LARGE HIGH PRESSURE OVER S ALBERTA AND SASKATCHEWAN
THURSDAY WILL SINK ACROSS THE N AND CENTRAL PLAINS...WHILE BUILDING
A RIDGE ACROSS LAKE SUPERIOR THURSDAY NIGHT THROUGH SATURDAY WITH
WINDS GUSTING TO AROUND 20KTS OR LESS.
&&
.HYDROLOGY...
ISSUED AT 359 AM EDT TUE SEP 9 2014
RAINFALL TOTALS FROM TONIGHT THROUGH WEDNESDAY NIGHT ACROSS UPPER MI
RANGE FROM JUST OVER 1.5IN TO NEARLY 3IN ACROSS THE KEWEENAW
PENINSULA AND FAVORABLE UPSLOPE ENHANCED LOCATIONS OF N CENTRAL
UPPER MI. AN AREAL FLOOD WATCH REMAINS POSTED FOR MUCH OF W AND
CENTRAL UPPER MI. MUCH OF THE CWA IS IN THE DAY 2 EXCESSIVE RAINFALL
POTENTIAL OUTLOOK /SLIGHT RISK/ FOR DAY 2 /12Z WED-12Z THU/. THE
MORNING RIVER FCSTS WILL BE RAN WITH 48HR QPF VALUES...SO IT WILL BE
INTERESTING TO SEE WHAT REACTION IS EXPECTED. OUR LAST RAIN EVENT
DID NOT DO MUCH AT THE RIVER GAUGE LOCATIONS. RIVERS THAT ARE
RUNNING HIGHER /GENERALLY 1-2FT/ THAN THIS TIME LAST MONTH INCLUDE
THE SOUTH BRANCH OF THE ONTONAGON RIVER AT EWEN...THE FORD RIVER AT
HYDE...THE STURGEON RIVER AT NAHMA JUNCTION...AND THE MANISTIQUE
RIVER AT MANISTIQUE.
AT THIS POINT THE N CENTRAL RFC 3HR FLASH FLOOD GUIDANCE IS HOVERING
BETWEEN 2-3.5IN...WITH 6HR FLASH FLOOD GUIDANCE IS CLOSER TO 2.25 TO
OVER 4IN. OF COURSE IT/S VERY TERRAIN AND BASIN SPECIFIC. AS
PREVIOUSLY NOTED...MANY AREAS OF W AND CENTRAL UPPER MI ARE RUNNING
AROUND 2-4IN ABOVE THE 2 WEEK NORMAL PRECIP WISE DUE TO RECENT HEAVY
RAINFALL. EXPECT THE TRADITIONAL URBAN/SMALL STREAM FLOODING TO BE A
SIGNIFICANT POSSIBILITY IN THE TYPICAL POOR DRAINAGE AREAS OF ESC IF
RAINFALL IS STEADY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FLOOD WATCH FROM 2 AM EDT /1 AM CDT/ WEDNESDAY THROUGH WEDNESDAY
EVENING FOR MIZ001>006-009>013-084.
LAKE SUPERIOR...
GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY MORNING FOR
LSZ251-267.
GALE WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY MORNING FOR
LSZ243>245-264>266.
GALE WATCH FROM WEDNESDAY MORNING THROUGH LATE WEDNESDAY NIGHT
FOR LSZ162-240>242-263.
GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY MORNING FOR
LSZ248>250.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...JLB
MARINE...KF
HYDROLOGY...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
133 PM EDT TUE SEP 9 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 438 AM EDT TUE SEP 9 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A WSW SPLIT FLOW
RUNNING ALONG THE CNDN BORDER. A SHRTWV WITHIN THE SRN BRANCH OVER
THE CONUS IS OVER NRN LK MI EARLY THIS MRNG AND WAS RESPONSIBLE FOR
SOME SPRINKLES THAT IMPACTED MAINLY THE SRN CWA SINCE YDAY AFTN. THE
ARRIVAL OF SOME SHRTWV RDGING/DEEP LYR QVECTOR DVGC/MID LVL DRYING
BEHIND THIS DISTURBANCE HAS ENDED THESE SPRINKLES...BUT AN AREA OF
SCT-BKN SC...RELATED TO H85 THETA E ADVCTN IN THE SW FLOW BTWN HI
PRES OVER NEW ENGLAND AND A COLD FNT SLIDING SEWD THRU NW ONTARIO/NW
MN...IS MOVING INTO THE WRN CWA. THE COLD FNT TO THE NW IS ATTENDANT
TO A SHRTWV NEAR JAMES BAY THAT IS LIFTING ENEWD WITHIN THE STRONGER
NRN BRANCH FLOW DOMINATING CANADA. SOME SHOWERS/TS ALONG THIS BNDRY
EXTENDED AS FAR AS ABOUT THE MN/ONTARIO BORDER...WHERE THE 00Z INL
RAOB SHOWS AN INVRN ARND H75 THAT IS SUFFICIENT TO CAP ANY
CONVECTION. THIS INVRN IS EVEN SHARPER ON THE MPX RAOB...
STRENGTHENED BY THE DEEP LYR QVECTOR DVGC IN THE WAKE OF SRN BRANCH
SHRTWV. LOOKING FARTHER UPSTREAM...THERE IS ANOTHER STRONGER SRN
BRANCH SHRTWV MOVING THRU NEVADA.
MAIN FCST CONCERN FOR TDAY IS WHETHER ANY SHOWERS/TS WL DVLP OVER
MAINLY WRN UPR MI AHEAD OF THE APRCHG COLD FNT FM THE NW. FOCUS FOR
TNGT WL SHIFT TO HOW QUICKLY LARGER AREA OF RA WL ARRIVE FM THE SW
IN ADVANCE OF SHRTWV NOW MOVING THRU THE CENTRAL ROCKIES.
TODAY...WHILE NRN BRANCH SHRTWV NEAR JAMES BAY WL CONTINUE ENEWD
INTO NRN QUEBEC...ATTENDANT COLD FNT IS FCST TO DROP SEWD INTO WRN
UPR MI THIS AFTN BUT THEN SLOW DOWN AS THE H5 FLOW BACKS SW/MORE
PARALLEL WITH THE FNT IN ADVANCE OF ROCKIES SHRTWV MOVING OUT INTO
THE CENTRAL PLAINS. WHILE THE SLOWING FNT MAY BE THE FOCUS FOR SOME
SHOWERS/TS IN THE PRESENCE OF DAYTIME HEATING...MODELS SHOW BULK OF
THE DEEP LYR QVECTOR CNVGC REMAINING TO THE N OF THE CWA CLOSER TO
LOW HGTS IN ONTARIO. IN THE ABSENCE OF THIS STRONGER LARGER SCALE
FORCING...SUSPECT MID LVL INVRN SHOWN ON THE UPSTREAM 00Z INL/MPX
RAOBS WL PERSIST IN LINE WITH THE GFS FCST SDNGS SHOWING LINGERING
INVRN ARND H75-8 AND LIMIT THE POTENTIAL FOR CONVECTION. SO WL
RETAIN GOING ONLY SCHC POPS OVER MAINLY THE W HALF FOR THE AFTN.
COMBINATION OF INCRSG H85 THETA E OVER THE FAR W TOWARD 00Z AND
ARRIVAL OF STRONGER FORCING IN ADVANCE OF APRCHG SHRTWV FM THE
PLAINS JUSTIFY INCRSG POPS OVER THE FAR W CLOSER TO THAT TIME AS GFS
FCST SDNG FOR IWD SHOWS WEAKENING INVRN TOWARD 00Z. AS FOR TEMPS...A
GOOD DEAL OF SC THAT WL FORM IN THE INCRSGLY MOIST S FLOW AHEAD OF
THE APRCHG FNT AND UNDER INVRN AS WELL AS FLOW OFF LK MI AS SFC
WINDS TEND TO BACK TOWARD THE SSE THRU THE DAY WL LIMIT THE RISE OF
THE MERCURY DESPITE WARM START TO THE DAY. TEMPS OVER THE W ARE
LIKELY TO FALL FOLLOWING PASSAGE OF THE SFC COLD FNT THIS AFTN AND
ARRIVAL OF SHALLOW COOL AIR.
TNGT...SHRTWV IN THE CENTRAL PLAINS WL MOVE NE...WITH FAIRLY DEEP
SFC LO ARND 996MB REACHING FAR NE IOWA TOWARD 12Z WED. ARRIVAL OF
SHARPER DEEP LYR QVECTOR CNVGC AND UPR DVGC IN ADVANCE OF THIS
DISTURBANCE AND OVER AXIS OF HIER H85 THETA E/PWAT AT LEAST NEAR
1.5 INCH WL BRING INCRSG POPS TO CATEGORICAL SW-NE...EXCEPT OVER THE
FAR E WHERE THE MORE IMPRESSIVE DYNAMICS WL NOT ARRIVE UNTIL AFTER
12Z WED. ALTHOUGH THIS SYNOPTIC SETUP FAVORS SOME HEAVY RA
ESPECIALLY OVER THE W HALF OVERNGT...THERE ARE A FEW LINGERING
QUESTION MARKS. THE FAVORED 00Z GFS MODEL INDICATES A BAND OF
SHARPER H85-7 FGEN WL SETUP ACRS CENTRAL WI OVERNGT...DISRUPTING
MSTR INFLOW INTO UPR MI. THE 00Z GFS GENERATES NO MORE THAN ABOUT
0.25-0.33 INCH OF RA THRU 12Z. SEVERAL OF THE HIER RES MODELS...
INCLUDING THE 00Z LOCAL WRF-ARW...GENERATE ONLY MINIMAL QPF OVER UPR
MI THRU 12Z WED. THE 00Z CNDN MODEL FOCUSES ITS HEAVIER PCPN TO THE
S OF THE CWA...CLOSER TO THAT AXIS OF FGEN SHOWN BY THE GFS. BUT
SINCE THE 00Z NAM...WHICH SHOWS A FARTHER NW TRACK FOR THE SFC LO
AND STRONGER SLY FLOW TO BRING HIER PWAT INTO THE CWA...AND THE 00Z
ECMWF DO PRODUCE GENEROUS RA OVER MAINLY THE W HALF...MADE NO CHG TO
GOING FLOOD WATCH FOR THE 06Z-12Z TIME. OTRW...THE SLOW MOVING COLD
FNT IS FCST TO SLIP ONLY SLOWLY SE THRU THE NGT...SO THE WARMEST
OVERNGT LO TEMPS WL BE OVER THE SE CWA.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 544 AM EDT TUE SEP 9 2014
WINDY AND WET THROUGH EARLY THURSDAY...WITH COOL AIR LINGERING
THROUGH AT LEAST EARLY NEXT WEEK. WITH THE COLD AIR...FROST OR
FREEZE CONDITIONS MAY BE POSSIBLE LATE THURSDAY NIGHT AND AGAIN
ACROSS A MAJORITY OF THE AREA LATE FRIDAY NIGHT. SEE THE HYDROLOGY
SECTION FOR MORE INFORMATION ON THE ONGOING FLOOD WATCH.
BY 12Z WEDNESDAY STEADY RAIN SHOULD ALREADY BE FALLING ACROSS MUCH
OF THE CWA...AS A TROUGH IS SPREAD ACROSS THE AREA AND DEEPENING LOW
PRESSURE ACROSS NE IA AND FAR SE MN NEARS.
WINDS WILL BE A CONCERN AS WE MOVE INTO WEDNESDAY AFTERNOON...AS THE
SFC LOW SHIFTS ACROSS SE UPPER MI AND N LOWER MI. GIVEN THE TRACK OF
THE LOW...A SLIGHT CHANCE OF TS WAS KEPT ALONG LAKE MI ON WEDNESDAY.
A FAVORABLE FETCH ACROSS LAKE SUPERIOR WILL ENHANCE N FLOW AND BRING
BREEZY TO WINDY CONDITIONS TO THE W HALF. A WIND ADVISORY MAY BE
NEEDED FOR THE KEWEENAW PENINSULA FOR WEDNESDAY AFTERNOON AND
EVENING. WILL KEEP THE MENTION OF STRONG WINDS IN THE HWO...WITH
SATURATED SOILS AND STRONG WINDS HITTING LEAFED OUT TREES HAVING A
BETTER CHANCE OF UPROOTING THEM.
THE STRONG WINDS WILL SLOWLY EXPAND OVER CENTRAL UPPER MI WEDNESDAY
NIGHT AS THE SFC LOW SLIDES ACROSS N LAKE HURON AND EXITS INTO
ONTARIO AND QUEBEC. WHILE THERE WILL BE A HIGH RISK OF RIP CURRENTS
TOMORROW THROUGH THURSDAY...OUR FORECAST FOR THIS PRODUCT WILL END
ON WEDNESDAY. WITH HIGHS IN THE LOW 60S AND PLENTY OF RAIN...THERE
WILL LIKELY BE LIMITED PEOPLE OUT IN THE WATER. LESS OF A SOCIAL
BROADCAST OF THE RIP CURRENT RISK WILL BE LIKELY...AS HEAVY RAIN AND
STRONG WINDS WILL BE THE MAIN CONCERNS.
COOL 850MB TEMPS OF 2 TO -1C AND FAVORABLE ONSHORE WINDS WILL KEEP
LAKE EFFECT CLOUDS AND SHOWERS GOING INTO THURSDAY. THE INFLUX OF
COLD AIR WILL BE IMPRESSIVE...AS 850MB TEMPS FALL FROM AROUND 11C AT
DAYBREAK WEDNSDAY. VERY COLD AIR FILTERING IN BEHIND THE EXITING LOW
COULD RESULT IN FROST OR FREEZE CONDITIONS NEAR THE WI BORDER LATE
THURSDAY NIGHT AS THE CANADIAN HIGH SINKS ACROSS THE N AND CENTRAL
PLAINS AND BUILDS A RIDGE ACROSS UPPER MI. LINGERING CLOUDS ON NW
FLOW SHOULD KEEP AREAS E OF A LINE FROM MARQUETTE TO ESCANABA FROM
FALLING TOO LOW. HOWEVER...LIGHT WINDS AND DRY CONDITIONS WITH PW
VALUES WELL BELOW NORMAL WILL HELP TEMPERATURES FALL INTO THE LOW TO
MID 30S ACROSS MUCH OF UPPER MI INLAND FROM THE GREAT LAKES LATE
FRIDAY NIGHT INTO EARLY SATURDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 132 PM EDT TUE SEP 9 2014
A COLD FRONT IS EXPECTED TO MOVE THROUGH IWD/CMX DURING THE
AFTERNOON...AND A WIND SHIFT TO THE NNE WITH THE ARRIVAL OF SOME
SHALLOW COOL AIR OFF LAKE SUPERIOR COULD BRING SOME MVFR CLDS INTO THOSE
LOCATIONS DURING THE AFTERNOON. THERE COULD BE A -SHRA OR PERHAPS
EVEN TS AT MAINLY IWD WITH THE ARRIVAL OF THE FRONT DURING PEAK
HEATING...BUT CONFIDENCE IS TOO LOW TO INCLUDE A SPECIFIC MENTION. AS
A STRONGER DISTURBANCE MOVES NEWD AND THE MOIST LYR DEEPENS...RAIN
WILL DEVELOP FROM SW TO NE AND CAUSE CONDITIONS AT IWD/CMX TO DROP TO
IFR BY LATE EVENING. SINCE THE FROPA WILL OCCUR LATER AT SAW...THE
TRANSITION TO MVFR WILL NOT OCCUR UNTIL LATER IN THE FCST PERIOD. BY
LATE TONIGHT INTO WED MORNING LIFR CONDITIONS WILL PREVAIL WITH
MODERATE TO OCNLY HEAVY RAIN.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 359 AM EDT TUE SEP 9 2014
THE TROUGH STRETCHED ACROSS W LAKE SUPERIOR WILL DRIFT ACROSS LAKE
SUPERIOR TODAY AS LOW PRESSURE NEARS FROM THE CENTRAL PLAINS. THE
LOW WILL BE OVER E IOWA BY DAYBREAK WEDNESDAY...AND CONTINUE TO PUSH
NE OVER E UPPER MI AND N LOWER MI LATE WEDNESDAY AFTERNOON...BEFORE
EXITING INTO QUEBEC ON THURSDAY. N GALES TO AROUND 40KTS WILL BE
POSSIBLE WEDNESDAY MORNING OVER W LAKE SUPERIOR...BEFORE SLOWLY
EXPANDING TO CENTRAL LAKE SUPERIOR WEDNESDAY EVENING THROUGH THE
OVERNIGHT HOURS. LARGE HIGH PRESSURE OVER S ALBERTA AND SASKATCHEWAN
THURSDAY WILL SINK ACROSS THE N AND CENTRAL PLAINS...WHILE BUILDING
A RIDGE ACROSS LAKE SUPERIOR THURSDAY NIGHT THROUGH SATURDAY WITH
WINDS GUSTING TO AROUND 20KTS OR LESS.
&&
.HYDROLOGY...
ISSUED AT 359 AM EDT TUE SEP 9 2014
RAINFALL TOTALS FROM TONIGHT THROUGH WEDNESDAY NIGHT ACROSS UPPER MI
RANGE FROM JUST OVER 1.5IN TO NEARLY 3IN ACROSS THE KEWEENAW
PENINSULA AND FAVORABLE UPSLOPE ENHANCED LOCATIONS OF N CENTRAL
UPPER MI. AN AREAL FLOOD WATCH REMAINS POSTED FOR MUCH OF W AND
CENTRAL UPPER MI. MUCH OF THE CWA IS IN THE DAY 2 EXCESSIVE RAINFALL
POTENTIAL OUTLOOK /SLIGHT RISK/ FOR DAY 2 /12Z WED-12Z THU/. THE
MORNING RIVER FCSTS WILL BE RAN WITH 48HR QPF VALUES...SO IT WILL BE
INTERESTING TO SEE WHAT REACTION IS EXPECTED. OUR LAST RAIN EVENT
DID NOT DO MUCH AT THE RIVER GAUGE LOCATIONS. RIVERS THAT ARE
RUNNING HIGHER /GENERALLY 1-2FT/ THAN THIS TIME LAST MONTH INCLUDE
THE SOUTH BRANCH OF THE ONTONAGON RIVER AT EWEN...THE FORD RIVER AT
HYDE...THE STURGEON RIVER AT NAHMA JUNCTION...AND THE MANISTIQUE
RIVER AT MANISTIQUE.
AT THIS POINT THE N CENTRAL RFC 3HR FLASH FLOOD GUIDANCE IS HOVERING
BETWEEN 2-3.5IN...WITH 6HR FLASH FLOOD GUIDANCE IS CLOSER TO 2.25 TO
OVER 4IN. OF COURSE IT/S VERY TERRAIN AND BASIN SPECIFIC. AS
PREVIOUSLY NOTED...MANY AREAS OF W AND CENTRAL UPPER MI ARE RUNNING
AROUND 2-4IN ABOVE THE 2 WEEK NORMAL PRECIP WISE DUE TO RECENT HEAVY
RAINFALL. EXPECT THE TRADITIONAL URBAN/SMALL STREAM FLOODING TO BE A
SIGNIFICANT POSSIBILITY IN THE TYPICAL POOR DRAINAGE AREAS OF ESC IF
RAINFALL IS STEADY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FLOOD WATCH FROM LATE TONIGHT THROUGH WEDNESDAY EVENING FOR
MIZ001>006-009>013-084.
LAKE SUPERIOR...
GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY MORNING FOR
LSZ251-267.
GALE WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY MORNING FOR
LSZ243>245-264>266.
GALE WATCH FROM WEDNESDAY MORNING THROUGH LATE WEDNESDAY NIGHT
FOR LSZ162-240>242-263.
GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY MORNING FOR
LSZ248>250.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...JLB
MARINE...KF
HYDROLOGY...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
738 AM EDT TUE SEP 9 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 438 AM EDT TUE SEP 9 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A WSW SPLIT FLOW
RUNNING ALONG THE CNDN BORDER. A SHRTWV WITHIN THE SRN BRANCH OVER
THE CONUS IS OVER NRN LK MI EARLY THIS MRNG AND WAS RESPONSIBLE FOR
SOME SPRINKLES THAT IMPACTED MAINLY THE SRN CWA SINCE YDAY AFTN. THE
ARRIVAL OF SOME SHRTWV RDGING/DEEP LYR QVECTOR DVGC/MID LVL DRYING
BEHIND THIS DISTURBANCE HAS ENDED THESE SPRINKLES...BUT AN AREA OF
SCT-BKN SC...RELATED TO H85 THETA E ADVCTN IN THE SW FLOW BTWN HI
PRES OVER NEW ENGLAND AND A COLD FNT SLIDING SEWD THRU NW ONTARIO/NW
MN...IS MOVING INTO THE WRN CWA. THE COLD FNT TO THE NW IS ATTENDANT
TO A SHRTWV NEAR JAMES BAY THAT IS LIFTING ENEWD WITHIN THE STRONGER
NRN BRANCH FLOW DOMINATING CANADA. SOME SHOWERS/TS ALONG THIS BNDRY
EXTENDED AS FAR AS ABOUT THE MN/ONTARIO BORDER...WHERE THE 00Z INL
RAOB SHOWS AN INVRN ARND H75 THAT IS SUFFICIENT TO CAP ANY
CONVECTION. THIS INVRN IS EVEN SHARPER ON THE MPX RAOB...
STRENGTHENED BY THE DEEP LYR QVECTOR DVGC IN THE WAKE OF SRN BRANCH
SHRTWV. LOOKING FARTHER UPSTREAM...THERE IS ANOTHER STRONGER SRN
BRANCH SHRTWV MOVING THRU NEVADA.
MAIN FCST CONCERN FOR TDAY IS WHETHER ANY SHOWERS/TS WL DVLP OVER
MAINLY WRN UPR MI AHEAD OF THE APRCHG COLD FNT FM THE NW. FOCUS FOR
TNGT WL SHIFT TO HOW QUICKLY LARGER AREA OF RA WL ARRIVE FM THE SW
IN ADVANCE OF SHRTWV NOW MOVING THRU THE CENTRAL ROCKIES.
TODAY...WHILE NRN BRANCH SHRTWV NEAR JAMES BAY WL CONTINUE ENEWD
INTO NRN QUEBEC...ATTENDANT COLD FNT IS FCST TO DROP SEWD INTO WRN
UPR MI THIS AFTN BUT THEN SLOW DOWN AS THE H5 FLOW BACKS SW/MORE
PARALLEL WITH THE FNT IN ADVANCE OF ROCKIES SHRTWV MOVING OUT INTO
THE CENTRAL PLAINS. WHILE THE SLOWING FNT MAY BE THE FOCUS FOR SOME
SHOWERS/TS IN THE PRESENCE OF DAYTIME HEATING...MODELS SHOW BULK OF
THE DEEP LYR QVECTOR CNVGC REMAINING TO THE N OF THE CWA CLOSER TO
LOW HGTS IN ONTARIO. IN THE ABSENCE OF THIS STRONGER LARGER SCALE
FORCING...SUSPECT MID LVL INVRN SHOWN ON THE UPSTREAM 00Z INL/MPX
RAOBS WL PERSIST IN LINE WITH THE GFS FCST SDNGS SHOWING LINGERING
INVRN ARND H75-8 AND LIMIT THE POTENTIAL FOR CONVECTION. SO WL
RETAIN GOING ONLY SCHC POPS OVER MAINLY THE W HALF FOR THE AFTN.
COMBINATION OF INCRSG H85 THETA E OVER THE FAR W TOWARD 00Z AND
ARRIVAL OF STRONGER FORCING IN ADVANCE OF APRCHG SHRTWV FM THE
PLAINS JUSTIFY INCRSG POPS OVER THE FAR W CLOSER TO THAT TIME AS GFS
FCST SDNG FOR IWD SHOWS WEAKENING INVRN TOWARD 00Z. AS FOR TEMPS...A
GOOD DEAL OF SC THAT WL FORM IN THE INCRSGLY MOIST S FLOW AHEAD OF
THE APRCHG FNT AND UNDER INVRN AS WELL AS FLOW OFF LK MI AS SFC
WINDS TEND TO BACK TOWARD THE SSE THRU THE DAY WL LIMIT THE RISE OF
THE MERCURY DESPITE WARM START TO THE DAY. TEMPS OVER THE W ARE
LIKELY TO FALL FOLLOWING PASSAGE OF THE SFC COLD FNT THIS AFTN AND
ARRIVAL OF SHALLOW COOL AIR.
TNGT...SHRTWV IN THE CENTRAL PLAINS WL MOVE NE...WITH FAIRLY DEEP
SFC LO ARND 996MB REACHING FAR NE IOWA TOWARD 12Z WED. ARRIVAL OF
SHARPER DEEP LYR QVECTOR CNVGC AND UPR DVGC IN ADVANCE OF THIS
DISTURBANCE AND OVER AXIS OF HIER H85 THETA E/PWAT AT LEAST NEAR
1.5 INCH WL BRING INCRSG POPS TO CATEGORICAL SW-NE...EXCEPT OVER THE
FAR E WHERE THE MORE IMPRESSIVE DYNAMICS WL NOT ARRIVE UNTIL AFTER
12Z WED. ALTHOUGH THIS SYNOPTIC SETUP FAVORS SOME HEAVY RA
ESPECIALLY OVER THE W HALF OVERNGT...THERE ARE A FEW LINGERING
QUESTION MARKS. THE FAVORED 00Z GFS MODEL INDICATES A BAND OF
SHARPER H85-7 FGEN WL SETUP ACRS CENTRAL WI OVERNGT...DISRUPTING
MSTR INFLOW INTO UPR MI. THE 00Z GFS GENERATES NO MORE THAN ABOUT
0.25-0.33 INCH OF RA THRU 12Z. SEVERAL OF THE HIER RES MODELS...
INCLUDING THE 00Z LOCAL WRF-ARW...GENERATE ONLY MINIMAL QPF OVER UPR
MI THRU 12Z WED. THE 00Z CNDN MODEL FOCUSES ITS HEAVIER PCPN TO THE
S OF THE CWA...CLOSER TO THAT AXIS OF FGEN SHOWN BY THE GFS. BUT
SINCE THE 00Z NAM...WHICH SHOWS A FARTHER NW TRACK FOR THE SFC LO
AND STRONGER SLY FLOW TO BRING HIER PWAT INTO THE CWA...AND THE 00Z
ECMWF DO PRODUCE GENEROUS RA OVER MAINLY THE W HALF...MADE NO CHG TO
GOING FLOOD WATCH FOR THE 06Z-12Z TIME. OTRW...THE SLOW MOVING COLD
FNT IS FCST TO SLIP ONLY SLOWLY SE THRU THE NGT...SO THE WARMEST
OVERNGT LO TEMPS WL BE OVER THE SE CWA.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 544 AM EDT TUE SEP 9 2014
WINDY AND WET THROUGH EARLY THURSDAY...WITH COOL AIR LINGERING
THROUGH AT LEAST EARLY NEXT WEEK. WITH THE COLD AIR...FROST OR
FREEZE CONDITIONS MAY BE POSSIBLE LATE THURSDAY NIGHT AND AGAIN
ACROSS A MAJORITY OF THE AREA LATE FRIDAY NIGHT. SEE THE HYDROLOGY
SECTION FOR MORE INFORMATION ON THE ONGOING FLOOD WATCH.
BY 12Z WEDNESDAY STEADY RAIN SHOULD ALREADY BE FALLING ACROSS MUCH
OF THE CWA...AS A TROUGH IS SPREAD ACROSS THE AREA AND DEEPENING LOW
PRESSURE ACROSS NE IA AND FAR SE MN NEARS.
WINDS WILL BE A CONCERN AS WE MOVE INTO WEDNESDAY AFTERNOON...AS THE
SFC LOW SHIFTS ACROSS SE UPPER MI AND N LOWER MI. GIVEN THE TRACK OF
THE LOW...A SLIGHT CHANCE OF TS WAS KEPT ALONG LAKE MI ON WEDNESDAY.
A FAVORABLE FETCH ACROSS LAKE SUPERIOR WILL ENHANCE N FLOW AND BRING
BREEZY TO WINDY CONDITIONS TO THE W HALF. A WIND ADVISORY MAY BE
NEEDED FOR THE KEWEENAW PENINSULA FOR WEDNESDAY AFTERNOON AND
EVENING. WILL KEEP THE MENTION OF STRONG WINDS IN THE HWO...WITH
SATURATED SOILS AND STRONG WINDS HITTING LEAFED OUT TREES HAVING A
BETTER CHANCE OF UPROOTING THEM.
THE STRONG WINDS WILL SLOWLY EXPAND OVER CENTRAL UPPER MI WEDNESDAY
NIGHT AS THE SFC LOW SLIDES ACROSS N LAKE HURON AND EXITS INTO
ONTARIO AND QUEBEC. WHILE THERE WILL BE A HIGH RISK OF RIP CURRENTS
TOMORROW THROUGH THURSDAY...OUR FORECAST FOR THIS PRODUCT WILL END
ON WEDNESDAY. WITH HIGHS IN THE LOW 60S AND PLENTY OF RAIN...THERE
WILL LIKELY BE LIMITED PEOPLE OUT IN THE WATER. LESS OF A SOCIAL
BROADCAST OF THE RIP CURRENT RISK WILL BE LIKELY...AS HEAVY RAIN AND
STRONG WINDS WILL BE THE MAIN CONCERNS.
COOL 850MB TEMPS OF 2 TO -1C AND FAVORABLE ONSHORE WINDS WILL KEEP
LAKE EFFECT CLOUDS AND SHOWERS GOING INTO THURSDAY. THE INFLUX OF
COLD AIR WILL BE IMPRESSIVE...AS 850MB TEMPS FALL FROM AROUND 11C AT
DAYBREAK WEDNSDAY. VERY COLD AIR FILTERING IN BEHIND THE EXITING LOW
COULD RESULT IN FROST OR FREEZE CONDITIONS NEAR THE WI BORDER LATE
THURSDAY NIGHT AS THE CANADIAN HIGH SINKS ACROSS THE N AND CENTRAL
PLAINS AND BUILDS A RIDGE ACROSS UPPER MI. LINGERING CLOUDS ON NW
FLOW SHOULD KEEP AREAS E OF A LINE FROM MARQUETTE TO ESCANABA FROM
FALLING TOO LOW. HOWEVER...LIGHT WINDS AND DRY CONDITIONS WITH PW
VALUES WELL BELOW NORMAL WILL HELP TEMPERATURES FALL INTO THE LOW TO
MID 30S ACROSS MUCH OF UPPER MI INLAND FROM THE GREAT LAKES LATE
FRIDAY NIGHT INTO EARLY SATURDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 738 AM EDT TUE SEP 9 2014
ALTHOUGH SOME SHALLOW GROUND FOG COULD IMPACT SAW EARLY THIS MRNG
AND THERE WL BE SOME HIER BASED SC...EXPECT VFR CONDITIONS TO
PREVAIL INTO AT LEAST EARLY AFTN WITH RELATIVELY DRY NEAR SFC LYR.
BUT A COLD FNT IS FCST TO PASS IWD/CMX DURING THE AFTN...AND A WSHFT
TO THE NNE/ARRIVAL OF SOME SHALLOW COOL AIR OFF LK SUP COULD BRING
SOME MVFR CLDS INTO THOSE LOCATIONS DURING THE AFTN. THERE COULD BE
A -SHRA OR PERHAPS EVEN TS AT MAINLY IWD WITH THE ARRIVAL OF THE FNT
DURING PEAK HEATING...BUT CONFIDENCE IS TOO LO TO INCLUDE A SPECIFIC
MENTION ATTM. AS A STRONGER DISTURBANCE MOVES NEWD AND THE MOIST LYR
DEEPENS...RA WL DVLP SW-NE AND CAUSE CONDITIONS AT IWD/CMX TO DROP
TO IFR BY LATE EVNG. SINCE THE FROPA WL OCCUR LATER AT SAW...THE
TRANSITION TO MVFR WL NOT OCCUR UNTIL LATER IN THE FCST PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 359 AM EDT TUE SEP 9 2014
THE TROUGH STRETCHED ACROSS W LAKE SUPERIOR WILL DRIFT ACROSS LAKE
SUPERIOR TODAY AS LOW PRESSURE NEARS FROM THE CENTRAL PLAINS. THE
LOW WILL BE OVER E IOWA BY DAYBREAK WEDNESDAY...AND CONTINUE TO PUSH
NE OVER E UPPER MI AND N LOWER MI LATE WEDNESDAY AFTERNOON...BEFORE
EXITING INTO QUEBEC ON THURSDAY. N GALES TO AROUND 40KTS WILL BE
POSSIBLE WEDNESDAY MORNING OVER W LAKE SUPERIOR...BEFORE SLOWLY
EXPANDING TO CENTRAL LAKE SUPERIOR WEDNESDAY EVENING THROUGH THE
OVERNIGHT HOURS. LARGE HIGH PRESSURE OVER S ALBERTA AND SASKATCHEWAN
THURSDAY WILL SINK ACROSS THE N AND CENTRAL PLAINS...WHILE BUILDING
A RIDGE ACROSS LAKE SUPERIOR THURSDAY NIGHT THROUGH SATURDAY WITH
WINDS GUSTING TO AROUND 20KTS OR LESS.
&&
.HYDROLOGY...
ISSUED AT 359 AM EDT TUE SEP 9 2014
RAINFALL TOTALS FROM TONIGHT THROUGH WEDNESDAY NIGHT ACROSS UPPER MI
RANGE FROM JUST OVER 1.5IN TO NEARLY 3IN ACROSS THE KEWEENAW
PENINSULA AND FAVORABLE UPSLOPE ENHANCED LOCATIONS OF N CENTRAL
UPPER MI. AN AREAL FLOOD WATCH REMAINS POSTED FOR MUCH OF W AND
CENTRAL UPPER MI. MUCH OF THE CWA IS IN THE DAY 2 EXCESSIVE RAINFALL
POTENTIAL OUTLOOK /SLIGHT RISK/ FOR DAY 2 /12Z WED-12Z THU/. THE
MORNING RIVER FCSTS WILL BE RAN WITH 48HR QPF VALUES...SO IT WILL BE
INTERESTING TO SEE WHAT REACTION IS EXPECTED. OUR LAST RAIN EVENT
DID NOT DO MUCH AT THE RIVER GAUGE LOCATIONS. RIVERS THAT ARE
RUNNING HIGHER /GENERALLY 1-2FT/ THAN THIS TIME LAST MONTH INCLUDE
THE SOUTH BRANCH OF THE ONTONAGON RIVER AT EWEN...THE FORD RIVER AT
HYDE...THE STURGEON RIVER AT NAHMA JUNCTION...AND THE MANISTIQUE
RIVER AT MANISTIQUE.
AT THIS POINT THE N CENTRAL RFC 3HR FLASH FLOOD GUIDANCE IS HOVERING
BETWEEN 2-3.5IN...WITH 6HR FLASH FLOOD GUIDANCE IS CLOSER TO 2.25 TO
OVER 4IN. OF COURSE IT/S VERY TERRAIN AND BASIN SPECIFIC. AS
PREVIOUSLY NOTED...MANY AREAS OF W AND CENTRAL UPPER MI ARE RUNNING
AROUND 2-4IN ABOVE THE 2 WEEK NORMAL PRECIP WISE DUE TO RECENT HEAVY
RAINFALL. EXPECT THE TRADITIONAL URBAN/SMALL STREAM FLOODING TO BE A
SIGNIFICANT POSSIBILITY IN THE TYPICAL POOR DRAINAGE AREAS OF ESC IF
RAINFALL IS STEADY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FLOOD WATCH FROM LATE TONIGHT THROUGH WEDNESDAY EVENING FOR
MIZ001>006-009>013-084.
LAKE SUPERIOR...
GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY MORNING FOR
LSZ251-267.
GALE WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY MORNING FOR
LSZ243>245-264>266.
GALE WATCH FROM WEDNESDAY MORNING THROUGH LATE WEDNESDAY NIGHT
FOR LSZ162-240>242-263.
GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY MORNING FOR
LSZ248>250.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...KC
MARINE...KF
HYDROLOGY...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
544 AM EDT TUE SEP 9 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 438 AM EDT TUE SEP 9 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A WSW SPLIT FLOW
RUNNING ALONG THE CNDN BORDER. A SHRTWV WITHIN THE SRN BRANCH OVER
THE CONUS IS OVER NRN LK MI EARLY THIS MRNG AND WAS RESPONSIBLE FOR
SOME SPRINKLES THAT IMPACTED MAINLY THE SRN CWA SINCE YDAY AFTN. THE
ARRIVAL OF SOME SHRTWV RDGING/DEEP LYR QVECTOR DVGC/MID LVL DRYING
BEHIND THIS DISTURBANCE HAS ENDED THESE SPRINKLES...BUT AN AREA OF
SCT-BKN SC...RELATED TO H85 THETA E ADVCTN IN THE SW FLOW BTWN HI
PRES OVER NEW ENGLAND AND A COLD FNT SLIDING SEWD THRU NW ONTARIO/NW
MN...IS MOVING INTO THE WRN CWA. THE COLD FNT TO THE NW IS ATTENDANT
TO A SHRTWV NEAR JAMES BAY THAT IS LIFTING ENEWD WITHIN THE STRONGER
NRN BRANCH FLOW DOMINATING CANADA. SOME SHOWERS/TS ALONG THIS BNDRY
EXTENDED AS FAR AS ABOUT THE MN/ONTARIO BORDER...WHERE THE 00Z INL
RAOB SHOWS AN INVRN ARND H75 THAT IS SUFFICIENT TO CAP ANY
CONVECTION. THIS INVRN IS EVEN SHARPER ON THE MPX RAOB...
STRENGTHENED BY THE DEEP LYR QVECTOR DVGC IN THE WAKE OF SRN BRANCH
SHRTWV. LOOKING FARTHER UPSTREAM...THERE IS ANOTHER STRONGER SRN
BRANCH SHRTWV MOVING THRU NEVADA.
MAIN FCST CONCERN FOR TDAY IS WHETHER ANY SHOWERS/TS WL DVLP OVER
MAINLY WRN UPR MI AHEAD OF THE APRCHG COLD FNT FM THE NW. FOCUS FOR
TNGT WL SHIFT TO HOW QUICKLY LARGER AREA OF RA WL ARRIVE FM THE SW
IN ADVANCE OF SHRTWV NOW MOVING THRU THE CENTRAL ROCKIES.
TODAY...WHILE NRN BRANCH SHRTWV NEAR JAMES BAY WL CONTINUE ENEWD
INTO NRN QUEBEC...ATTENDANT COLD FNT IS FCST TO DROP SEWD INTO WRN
UPR MI THIS AFTN BUT THEN SLOW DOWN AS THE H5 FLOW BACKS SW/MORE
PARALLEL WITH THE FNT IN ADVANCE OF ROCKIES SHRTWV MOVING OUT INTO
THE CENTRAL PLAINS. WHILE THE SLOWING FNT MAY BE THE FOCUS FOR SOME
SHOWERS/TS IN THE PRESENCE OF DAYTIME HEATING...MODELS SHOW BULK OF
THE DEEP LYR QVECTOR CNVGC REMAINING TO THE N OF THE CWA CLOSER TO
LOW HGTS IN ONTARIO. IN THE ABSENCE OF THIS STRONGER LARGER SCALE
FORCING...SUSPECT MID LVL INVRN SHOWN ON THE UPSTREAM 00Z INL/MPX
RAOBS WL PERSIST IN LINE WITH THE GFS FCST SDNGS SHOWING LINGERING
INVRN ARND H75-8 AND LIMIT THE POTENTIAL FOR CONVECTION. SO WL
RETAIN GOING ONLY SCHC POPS OVER MAINLY THE W HALF FOR THE AFTN.
COMBINATION OF INCRSG H85 THETA E OVER THE FAR W TOWARD 00Z AND
ARRIVAL OF STRONGER FORCING IN ADVANCE OF APRCHG SHRTWV FM THE
PLAINS JUSTIFY INCRSG POPS OVER THE FAR W CLOSER TO THAT TIME AS GFS
FCST SDNG FOR IWD SHOWS WEAKENING INVRN TOWARD 00Z. AS FOR TEMPS...A
GOOD DEAL OF SC THAT WL FORM IN THE INCRSGLY MOIST S FLOW AHEAD OF
THE APRCHG FNT AND UNDER INVRN AS WELL AS FLOW OFF LK MI AS SFC
WINDS TEND TO BACK TOWARD THE SSE THRU THE DAY WL LIMIT THE RISE OF
THE MERCURY DESPITE WARM START TO THE DAY. TEMPS OVER THE W ARE
LIKELY TO FALL FOLLOWING PASSAGE OF THE SFC COLD FNT THIS AFTN AND
ARRIVAL OF SHALLOW COOL AIR.
TNGT...SHRTWV IN THE CENTRAL PLAINS WL MOVE NE...WITH FAIRLY DEEP
SFC LO ARND 996MB REACHING FAR NE IOWA TOWARD 12Z WED. ARRIVAL OF
SHARPER DEEP LYR QVECTOR CNVGC AND UPR DVGC IN ADVANCE OF THIS
DISTURBANCE AND OVER AXIS OF HIER H85 THETA E/PWAT AT LEAST NEAR
1.5 INCH WL BRING INCRSG POPS TO CATEGORICAL SW-NE...EXCEPT OVER THE
FAR E WHERE THE MORE IMPRESSIVE DYNAMICS WL NOT ARRIVE UNTIL AFTER
12Z WED. ALTHOUGH THIS SYNOPTIC SETUP FAVORS SOME HEAVY RA
ESPECIALLY OVER THE W HALF OVERNGT...THERE ARE A FEW LINGERING
QUESTION MARKS. THE FAVORED 00Z GFS MODEL INDICATES A BAND OF
SHARPER H85-7 FGEN WL SETUP ACRS CENTRAL WI OVERNGT...DISRUPTING
MSTR INFLOW INTO UPR MI. THE 00Z GFS GENERATES NO MORE THAN ABOUT
0.25-0.33 INCH OF RA THRU 12Z. SEVERAL OF THE HIER RES MODELS...
INCLUDING THE 00Z LOCAL WRF-ARW...GENERATE ONLY MINIMAL QPF OVER UPR
MI THRU 12Z WED. THE 00Z CNDN MODEL FOCUSES ITS HEAVIER PCPN TO THE
S OF THE CWA...CLOSER TO THAT AXIS OF FGEN SHOWN BY THE GFS. BUT
SINCE THE 00Z NAM...WHICH SHOWS A FARTHER NW TRACK FOR THE SFC LO
AND STRONGER SLY FLOW TO BRING HIER PWAT INTO THE CWA...AND THE 00Z
ECMWF DO PRODUCE GENEROUS RA OVER MAINLY THE W HALF...MADE NO CHG TO
GOING FLOOD WATCH FOR THE 06Z-12Z TIME. OTRW...THE SLOW MOVING COLD
FNT IS FCST TO SLIP ONLY SLOWLY SE THRU THE NGT...SO THE WARMEST
OVERNGT LO TEMPS WL BE OVER THE SE CWA.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 544 AM EDT TUE SEP 9 2014
WINDY AND WET THROUGH EARLY THURSDAY...WITH COOL AIR LINGERING
THROUGH AT LEAST EARLY NEXT WEEK. WITH THE COLD AIR...FROST OR
FREEZE CONDITIONS MAY BE POSSIBLE LATE THURSDAY NIGHT AND AGAIN
ACROSS A MAJORITY OF THE AREA LATE FRIDAY NIGHT. SEE THE HYDROLOGY
SECTION FOR MORE INFORMATION ON THE ONGOING FLOOD WATCH.
BY 12Z WEDNESDAY STEADY RAIN SHOULD ALREADY BE FALLING ACROSS MUCH
OF THE CWA...AS A TROUGH IS SPREAD ACROSS THE AREA AND DEEPENING LOW
PRESSURE ACROSS NE IA AND FAR SE MN NEARS.
WINDS WILL BE A CONCERN AS WE MOVE INTO WEDNESDAY AFTERNOON...AS THE
SFC LOW SHIFTS ACROSS SE UPPER MI AND N LOWER MI. GIVEN THE TRACK OF
THE LOW...A SLIGHT CHANCE OF TS WAS KEPT ALONG LAKE MI ON WEDNESDAY.
A FAVORABLE FETCH ACROSS LAKE SUPERIOR WILL ENHANCE N FLOW AND BRING
BREEZY TO WINDY CONDITIONS TO THE W HALF. A WIND ADVISORY MAY BE
NEEDED FOR THE KEWEENAW PENINSULA FOR WEDNESDAY AFTERNOON AND
EVENING. WILL KEEP THE MENTION OF STRONG WINDS IN THE HWO...WITH
SATURATED SOILS AND STRONG WINDS HITTING LEAFED OUT TREES HAVING A
BETTER CHANCE OF UPROOTING THEM.
THE STRONG WINDS WILL SLOWLY EXPAND OVER CENTRAL UPPER MI WEDNESDAY
NIGHT AS THE SFC LOW SLIDES ACROSS N LAKE HURON AND EXITS INTO
ONTARIO AND QUEBEC. WHILE THERE WILL BE A HIGH RISK OF RIP CURRENTS
TOMORROW THROUGH THURSDAY...OUR FORECAST FOR THIS PRODUCT WILL END
ON WEDNESDAY. WITH HIGHS IN THE LOW 60S AND PLENTY OF RAIN...THERE
WILL LIKELY BE LIMITED PEOPLE OUT IN THE WATER. LESS OF A SOCIAL
BROADCAST OF THE RIP CURRENT RISK WILL BE LIKELY...AS HEAVY RAIN AND
STRONG WINDS WILL BE THE MAIN CONCERNS.
COOL 850MB TEMPS OF 2 TO -1C AND FAVORABLE ONSHORE WINDS WILL KEEP
LAKE EFFECT CLOUDS AND SHOWERS GOING INTO THURSDAY. THE INFLUX OF
COLD AIR WILL BE IMPRESSIVE...AS 850MB TEMPS FALL FROM AROUND 11C AT
DAYBREAK WEDNSDAY. VERY COLD AIR FILTERING IN BEHIND THE EXITING LOW
COULD RESULT IN FROST OR FREEZE CONDITIONS NEAR THE WI BORDER LATE
THURSDAY NIGHT AS THE CANADIAN HIGH SINKS ACROSS THE N AND CENTRAL
PLAINS AND BUILDS A RIDGE ACROSS UPPER MI. LINGERING CLOUDS ON NW
FLOW SHOULD KEEP AREAS E OF A LINE FROM MARQUETTE TO ESCANABA FROM
FALLING TOO LOW. HOWEVER...LIGHT WINDS AND DRY CONDITIONS WITH PW
VALUES WELL BELOW NORMAL WILL HELP TEMPERATURES FALL INTO THE LOW TO
MID 30S ACROSS MUCH OF UPPER MI INLAND FROM THE GREAT LAKES LATE
FRIDAY NIGHT INTO EARLY SATURDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 121 AM EDT TUE SEP 9 2014
VFR CONDITIONS WILL PREVAIL THRU SUNRISE AND LIKELY THRU MOST OF THE
AFTN AT KIWD/KCMX/KSAW AS LOW LEVELS REMAIN RELATIVELY DRY. SHARP
COLD FRONT CURRENTLY EXTENDING FROM SOUTHERN HUDSON BAY THRU NW MN
WILL DRIFT S...REACHING W AND NW UPPER MI LATE THIS AFTN/EVENING.
CIGS SHOULD QUICKLY FALL TO LOW MVFR AND PERHAPS IFR AT KCMX/KIWD
AFTER FROPA PER UPSTREAM OBS BEHIND FRONT. THERE MAY BE SOME SHRA OR
EVEN TSTMS IN THE VCNTY OF THE FRONT...BUT CONFIDENCE ON
COVERAGE/LOCATION OF PCPN IS LOW. FOR NOW...ONLY VCSH WAS INCLUDED IN
FCST.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 359 AM EDT TUE SEP 9 2014
THE TROUGH STRETCHED ACROSS W LAKE SUPERIOR WILL DRIFT ACROSS LAKE
SUPERIOR TODAY AS LOW PRESSURE NEARS FROM THE CENTRAL PLAINS. THE
LOW WILL BE OVER E IOWA BY DAYBREAK WEDNESDAY...AND CONTINUE TO PUSH
NE OVER E UPPER MI AND N LOWER MI LATE WEDNESDAY AFTERNOON...BEFORE
EXITING INTO QUEBEC ON THURSDAY. N GALES TO AROUND 40KTS WILL BE
POSSIBLE WEDNESDAY MORNING OVER W LAKE SUPERIOR...BEFORE SLOWLY
EXPANDING TO CENTRAL LAKE SUPERIOR WEDNESDAY EVENING THROUGH THE
OVERNIGHT HOURS. LARGE HIGH PRESSURE OVER S ALBERTA AND SASKATCHEWAN
THURSDAY WILL SINK ACROSS THE N AND CENTRAL PLAINS...WHILE BUILDING
A RIDGE ACROSS LAKE SUPERIOR THURSDAY NIGHT THROUGH SATURDAY WITH
WINDS GUSTING TO AROUND 20KTS OR LESS.
&&
.HYDROLOGY...
ISSUED AT 359 AM EDT TUE SEP 9 2014
RAINFALL TOTALS FROM TONIGHT THROUGH WEDNESDAY NIGHT ACROSS UPPER MI
RANGE FROM JUST OVER 1.5IN TO NEARLY 3IN ACROSS THE KEWEENAW
PENINSULA AND FAVORABLE UPSLOPE ENHANCED LOCATIONS OF N CENTRAL
UPPER MI. AN AREAL FLOOD WATCH REMAINS POSTED FOR MUCH OF W AND
CENTRAL UPPER MI. MUCH OF THE CWA IS IN THE DAY 2 EXCESSIVE RAINFALL
POTENTIAL OUTLOOK /SLIGHT RISK/ FOR DAY 2 /12Z WED-12Z THU/. THE
MORNING RIVER FCSTS WILL BE RAN WITH 48HR QPF VALUES...SO IT WILL BE
INTERESTING TO SEE WHAT REACTION IS EXPECTED. OUR LAST RAIN EVENT
DID NOT DO MUCH AT THE RIVER GAUGE LOCATIONS. RIVERS THAT ARE
RUNNING HIGHER /GENERALLY 1-2FT/ THAN THIS TIME LAST MONTH INCLUDE
THE SOUTH BRANCH OF THE ONTONAGON RIVER AT EWEN...THE FORD RIVER AT
HYDE...THE STURGEON RIVER AT NAHMA JUNCTION...AND THE MANISTIQUE
RIVER AT MANISTIQUE.
AT THIS POINT THE N CENTRAL RFC 3HR FLASH FLOOD GUIDANCE IS HOVERING
BETWEEN 2-3.5IN...WITH 6HR FLASH FLOOD GUIDANCE IS CLOSER TO 2.25 TO
OVER 4IN. OF COURSE IT/S VERY TERRAIN AND BASIN SPECIFIC. AS
PREVIOUSLY NOTED...MANY AREAS OF W AND CENTRAL UPPER MI ARE RUNNING
AROUND 2-4IN ABOVE THE 2 WEEK NORMAL PRECIP WISE DUE TO RECENT HEAVY
RAINFALL. EXPECT THE TRADITIONAL URBAN/SMALL STREAM FLOODING TO BE A
SIGNIFICANT POSSIBILITY IN THE TYPICAL POOR DRAINAGE AREAS OF ESC IF
RAINFALL IS STEADY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FLOOD WATCH FROM LATE TONIGHT THROUGH WEDNESDAY EVENING FOR
MIZ001>006-009>013-084.
LAKE SUPERIOR...
GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY MORNING FOR
LSZ251-267.
GALE WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY MORNING FOR
LSZ243>245-264>266.
GALE WATCH FROM WEDNESDAY MORNING THROUGH LATE WEDNESDAY NIGHT
FOR LSZ162-240>242-263.
GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY MORNING FOR
LSZ248>250.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...ROLFSON
MARINE...KF
HYDROLOGY...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
438 AM EDT TUE SEP 9 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 438 AM EDT TUE SEP 9 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A WSW SPLIT FLOW
RUNNING ALONG THE CNDN BORDER. A SHRTWV WITHIN THE SRN BRANCH OVER
THE CONUS IS OVER NRN LK MI EARLY THIS MRNG AND WAS RESPONSIBLE FOR
SOME SPRINKLES THAT IMPACTED MAINLY THE SRN CWA SINCE YDAY AFTN. THE
ARRIVAL OF SOME SHRTWV RDGING/DEEP LYR QVECTOR DVGC/MID LVL DRYING
BEHIND THIS DISTURBANCE HAS ENDED THESE SPRINKLES...BUT AN AREA OF
SCT-BKN SC...RELATED TO H85 THETA E ADVCTN IN THE SW FLOW BTWN HI
PRES OVER NEW ENGLAND AND A COLD FNT SLIDING SEWD THRU NW ONTARIO/NW
MN...IS MOVING INTO THE WRN CWA. THE COLD FNT TO THE NW IS ATTENDANT
TO A SHRTWV NEAR JAMES BAY THAT IS LIFTING ENEWD WITHIN THE STRONGER
NRN BRANCH FLOW DOMINATING CANADA. SOME SHOWERS/TS ALONG THIS BNDRY
EXTENDED AS FAR AS ABOUT THE MN/ONTARIO BORDER...WHERE THE 00Z INL
RAOB SHOWS AN INVRN ARND H75 THAT IS SUFFICIENT TO CAP ANY
CONVECTION. THIS INVRN IS EVEN SHARPER ON THE MPX RAOB...
STRENGTHENED BY THE DEEP LYR QVECTOR DVGC IN THE WAKE OF SRN BRANCH
SHRTWV. LOOKING FARTHER UPSTREAM...THERE IS ANOTHER STRONGER SRN
BRANCH SHRTWV MOVING THRU NEVADA.
MAIN FCST CONCERN FOR TDAY IS WHETHER ANY SHOWERS/TS WL DVLP OVER
MAINLY WRN UPR MI AHEAD OF THE APRCHG COLD FNT FM THE NW. FOCUS FOR
TNGT WL SHIFT TO HOW QUICKLY LARGER AREA OF RA WL ARRIVE FM THE SW
IN ADVANCE OF SHRTWV NOW MOVING THRU THE CENTRAL ROCKIES.
TODAY...WHILE NRN BRANCH SHRTWV NEAR JAMES BAY WL CONTINUE ENEWD
INTO NRN QUEBEC...ATTENDANT COLD FNT IS FCST TO DROP SEWD INTO WRN
UPR MI THIS AFTN BUT THEN SLOW DOWN AS THE H5 FLOW BACKS SW/MORE
PARALLEL WITH THE FNT IN ADVANCE OF ROCKIES SHRTWV MOVING OUT INTO
THE CENTRAL PLAINS. WHILE THE SLOWING FNT MAY BE THE FOCUS FOR SOME
SHOWERS/TS IN THE PRESENCE OF DAYTIME HEATING...MODELS SHOW BULK OF
THE DEEP LYR QVECTOR CNVGC REMAINING TO THE N OF THE CWA CLOSER TO
LOW HGTS IN ONTARIO. IN THE ABSENCE OF THIS STRONGER LARGER SCALE
FORCING...SUSPECT MID LVL INVRN SHOWN ON THE UPSTREAM 00Z INL/MPX
RAOBS WL PERSIST IN LINE WITH THE GFS FCST SDNGS SHOWING LINGERING
INVRN ARND H75-8 AND LIMIT THE POTENTIAL FOR CONVECTION. SO WL
RETAIN GOING ONLY SCHC POPS OVER MAINLY THE W HALF FOR THE AFTN.
COMBINATION OF INCRSG H85 THETA E OVER THE FAR W TOWARD 00Z AND
ARRIVAL OF STRONGER FORCING IN ADVANCE OF APRCHG SHRTWV FM THE
PLAINS JUSTIFY INCRSG POPS OVER THE FAR W CLOSER TO THAT TIME AS GFS
FCST SDNG FOR IWD SHOWS WEAKENING INVRN TOWARD 00Z. AS FOR TEMPS...A
GOOD DEAL OF SC THAT WL FORM IN THE INCRSGLY MOIST S FLOW AHEAD OF
THE APRCHG FNT AND UNDER INVRN AS WELL AS FLOW OFF LK MI AS SFC
WINDS TEND TO BACK TOWARD THE SSE THRU THE DAY WL LIMIT THE RISE OF
THE MERCURY DESPITE WARM START TO THE DAY. TEMPS OVER THE W ARE
LIKELY TO FALL FOLLOWING PASSAGE OF THE SFC COLD FNT THIS AFTN AND
ARRIVAL OF SHALLOW COOL AIR.
TNGT...SHRTWV IN THE CENTRAL PLAINS WL MOVE NE...WITH FAIRLY DEEP
SFC LO ARND 996MB REACHING FAR NE IOWA TOWARD 12Z WED. ARRIVAL OF
SHARPER DEEP LYR QVECTOR CNVGC AND UPR DVGC IN ADVANCE OF THIS
DISTURBANCE AND OVER AXIS OF HIER H85 THETA E/PWAT AT LEAST NEAR
1.5 INCH WL BRING INCRSG POPS TO CATEGORICAL SW-NE...EXCEPT OVER THE
FAR E WHERE THE MORE IMPRESSIVE DYNAMICS WL NOT ARRIVE UNTIL AFTER
12Z WED. ALTHOUGH THIS SYNOPTIC SETUP FAVORS SOME HEAVY RA
ESPECIALLY OVER THE W HALF OVERNGT...THERE ARE A FEW LINGERING
QUESTION MARKS. THE FAVORED 00Z GFS MODEL INDICATES A BAND OF
SHARPER H85-7 FGEN WL SETUP ACRS CENTRAL WI OVERNGT...DISRUPTING
MSTR INFLOW INTO UPR MI. THE 00Z GFS GENERATES NO MORE THAN ABOUT
0.25-0.33 INCH OF RA THRU 12Z. SEVERAL OF THE HIER RES MODELS...
INCLUDING THE 00Z LOCAL WRF-ARW...GENERATE ONLY MINIMAL QPF OVER UPR
MI THRU 12Z WED. THE 00Z CNDN MODEL FOCUSES ITS HEAVIER PCPN TO THE
S OF THE CWA...CLOSER TO THAT AXIS OF FGEN SHOWN BY THE GFS. BUT
SINCE THE 00Z NAM...WHICH SHOWS A FARTHER NW TRACK FOR THE SFC LO
AND STRONGER SLY FLOW TO BRING HIER PWAT INTO THE CWA...AND THE 00Z
ECMWF DO PRODUCE GENEROUS RA OVER MAINLY THE W HALF...MADE NO CHG TO
GOING FLOOD WATCH FOR THE 06Z-12Z TIME. OTRW...THE SLOW MOVING COLD
FNT IS FCST TO SLIP ONLY SLOWLY SE THRU THE NGT...SO THE WARMEST
OVERNGT LO TEMPS WL BE OVER THE SE CWA.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 431 PM EDT MON SEP 8 2014
THE MAIN ISSUES THIS FORECAST PERIOD WILL BE THE FLOODING POTENTIAL
TUESDAY NIGHT THROUGH WEDNESDAY MORNING...GALES ON LAKE SUPERIOR
WEDNESDAY INTO WEDNESDAY NIGHT AND COLDER THAN NORMAL TEMPERATURES
MOVING IN THURSDAY NIGHT THROUGH SATURDAY.
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...LOW PRESSURE WILL INTENSIFY
OVER THE CENTRAL PLAINS AS IT LIFTS NORTHEASTWARD TO WESTERN IOWA
LATE TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING AT OR AROUND 1000MB.
AT THE SAME TIME...AN UPPER LEVEL 500MB TROUGH AXIS SLIDES ACROSS
THE ROCKIES INTO THE PLAINS STATES. MODELS ARE IN FAIRLY GOOD
AGREEMENT...HOWEVER...THE 12Z NAM IS A BIT OF AN OUTLIER...TAKING
THE LOW FARTHER NORTH AND WEST THAN THE OTHER MODELS. SHOWERS AND
THUNDERSTORMS WILL DEVELOP AHEAD OF THE LOW PRESSURE SYSTEM ON
INCREASED MOISTURE UPGLIDE AS SHOWN ON THE 300K ISOSURFACE ALONG
WITH INCREASING MOISTURE SHOWN BY PLOTTING 1000-500 RH. THE BEST
CHANCE OF CONVECTION WOULD BE TUESDAY EVENING WITH INSTABILITY
LINGERING ON THE WARM SIDE OF THE LOW. THE LOW WILL CONTINUE
NORTHEASTWARD TO JUST SOUTH OF JAMES BAY WHILE FURTHER STRENGTHENING
TO AROUND 990MB AS THE UPPER LEVEL TROUGH SLIDES INTO THE UPPER
MISSISSIPPI VALLEY. AT THIS POINT...THE HEAVY RAINFALL POTENTIAL
WOULD BE GREATEST LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING...AS
DEEP LAYER MOISTURE WOULD BE IN PLACE AT THE SAME TIME ISENTROPIC
UPGLIDE IS MAXIMIZED AND DEEP LAYER FORCING IS MAXIMIZED AS A FAIRLY
STRONG 700MB FGEN BAND WRAPS THROUGH THE AREA. ADDITIONALLY...THE
AREA WILL LIE IN THE LEFT EXIT REGION OF A JET MAX TO THE SOUTH AND
PARTIALLY IN THE INFLUENCE OF A RIGHT ENTRANCE REGION OF A JET MAX
TO THE NORTH. ALSO IN SUPPORT OF HEAVY RAINFALL TUESDAY NIGHT
THROUGH WEDNESDAY MORNING WILL BE PWAT VALUES CONTINUING TO BE
PROGGED AT 1.5 TO 2 INCHES ON STRONG SOUTHERLY MOISTURE TRANSPORT
INTO THE REGION. RAINFALL WILL CONTINUE THROUGH WEDNESDAY
NIGHT...HOWEVER...OVERALL INTENSITY IS EXPECTED TO DECREASE AS THE
AFOREMENTIONED HEAVY RAINFALL FEATURES SHIFT OUT OF THE AREA AND
MAINLY WRAP AROUND PRECIP LINGERS OVER GENERALLY THE WESTERN U.P. AS
A DRY SLOT IS PROGGED TO WEDGE INTO THE CENTRAL AND EASTERN
AREAS...ALLOWING FOR MAINLY DRIZZLE.
HEAVY RAINFALL POTENTIAL INCLUDING AREAL FLOOD WATCH...WITH THE DEEP
MOISTURE AND LIFT EXPECTED ACROSS THE AREA...RAINFALL TOTALS WILL
LIKELY EXCEED 2 INCHES WITH UP TO 3 INCHES POSSIBLE ACROSS PORTIONS
OF THE CENTRAL AND WESTERN UPPER PENINSULA. MOST OF THE RAINFALL IS
EXPECTED TO OCCUR IN A 12 HOUR PERIOD...BETWEEN 06Z/10 AND 18Z/10.
THIS HEAVY RAINFALL WILL OCCUR ON VERY SATURATED SOILS WHICH WILL
ALLOW RUNOFF TO BEGIN QUICKLY. MANY AREAS OF THE CENTRAL AND WESTERN
PORTIONS OF THE U.P. ARE RUNNING AROUND 2 TO 4 INCHES ABOVE THE 2
WEEK NORMAL DUE TO RECENT HEAVY RAINFALL. SEVERAL RIVERS WITHIN THE
FLOOD WATCH ARE RUNNING HIGHER THAN NORMAL WITH ANY ADDITIONAL
WIDESPREAD RAINFALL EXPECTED TO INCREASE THESE LEVEL...SOME OF WHICH
MAY APPROACH FLOOD STAGE...BASED ON HEAVIER RAINFALL GUIDANCE.
OUTSIDE OF THE RAINFALL POTENTIAL...STRONG WINDS WILL ALSO BE AN
ISSUE. AS THE LOW PUSHES INTO THE REGION...A FAIRLY STRONG AREA OF
HIGH PRESSURE WILL BUILD ACROSS MUCH OF WESTERN CANADA. THE PRESSURE
GRADIENT WILL TIGHTEN BETWEEN THE TWO SYSTEMS LATE TUESDAY NIGHT AND
ESPECIALLY DURING THE DAY WEDNESDAY. THE PERIOD OF STRONGEST WINDS
ARE EXPECTED TO PUSH THROUGH THE AREA LATE WEDNESDAY MORNING THROUGH
LATE WEDNESDAY NIGHT. WINDS OVER MUCH OF THE LAND AREAS AWAY FROM
THE SHORE WILL BE SUSTAINED AROUND 15 TO 25 MPH. OVER THE LAKE...THE
KEWEENAW PENINSULA AND AREAS NEAR THE SHORE WILL SEE WINDS
SUSTAINED CLOSER TO 35 TO 40 MPH WITH GUSTS REACHING AROUND 45 TO
EVEN 50 MPH. THIS IS SUPPORTED WITH CAA ACROSS THE LAKE ON THE BACK
SIDE OF THE LOW WITH RELATIVELY WARM LAKE SURFACE TEMPERATURES
ALLOWING STRONGER WINDS TO MIX DOWN TO THE LAKE SURFACE. SOUNDINGS
SUPPORT WINDS MIXING DOWN FROM AROUND 925-900MB...WHERE WINDS ARE
PROGGED TO BE RIGHT AROUND 45 TO 50 MPH. CONFIDENCE IN HIGH WINDS IS
FAIRLY HIGH OVER THE LAKE...WITH A BIT LOWER CONFIDENCE IN THE WIND
DIRECTION. HAVE DECIDED TO GO WITH A GALE WATCH BEGINNING WEDNESDAY
MORNING INTO LATE WEDNESDAY NIGHT.
THURSDAY THROUGH FRIDAY NIGHT...THE LOW PRESSURE SYSTEM NEAR JAMES
BAY WILL CONTINUE TO SLOWLY LIFT NORTHEAST...PUSHING INTO QUEBEC BY
THURSDAY AFTERNOON. AT THE SAME TIME...STRONG HIGH PRESSURE WILL
BUILD ACROSS MUCH OF THE UPPER MISSISSIPPI VALLEY. THE PRESSURE
GRADIENT MAY LINGER THROUGH THURSDAY MORNING OVER EASTERN LAKE
SUPERIOR KEEPING GALE FORCE GUSTS IN THE FORECAST...HOWEVER...AS THE
LOW SLIPS AWAY AND THE HIGH BUILDS IN...WINDS WILL DIMINISH DURING
THE AFTERNOON HOURS THURSDAY. UPPER LEVEL TROUGHING WILL LINGER
THROUGH FRIDAY NIGHT ACROSS THE AREA WITH A COUPLE SHORTWAVES
PUSHING THROUGH. THE COOLER AIR ALOFT ASSOCIATED WITH THE TROUGH
WILL ALLOW FOR CONTINUED CLOUD COVER ALONG WITH LIGHT RAIN SHOWERS.
BY LATE FRIDAY NIGHT THE HIGH PRESSURE CENTER MOVES OVERHEAD ALONG
WITH SLIGHT RIDGING ALOFT AND DRIER AIR...ALLOWING THE PRECIP TO END
AND SKIES TO CLEAR. TEMPERATURES COULD BE QUITE COOL FRIDAY NIGHT
WITH CALM CONDITIONS...CLEARING SKIES AND PWAT VALUES AROUND 30 TO
40 PERCENT OF NORMAL. KEPT THE IDEA OF SEEING BELOW FREEZING
TEMPERATURES ACROSS INLAND AREAS OF THE U.P.
SATURDAY THROUGH MONDAY...HIGH PRESSURE IS EXPECTED TO LINGER
THROUGH SATURDAY...KEEPING CONDITIONS DRY AND SKIES MAINLY CLEAR.
TEMPERATURES WILL BEGIN TO MODERATE SUNDAY INTO MONDAY ON RETURN
SOUTHERLY FLOW ON THE WEST SIDE OF THE HIGH. THE GFS/EC HAVE ANOTHER
SYSTEM PUSHING INTO THE AREA DURING THE SUNDAY NIGHT INTO MONDAY
TIME PERIOD...HOWEVER...THERE IS QUITE A BIT OF UNCERTAINTY IN THE
TRACK OF THE SYSTEM AND THE OVERALL STRENGTH AND TIMING OF THE UPPER
LEVEL TROUGH. LEANED HEAVILY ON A CONSENSUS OF THE MODELS DURING
THIS TIME PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 121 AM EDT TUE SEP 9 2014
VFR CONDITIONS WILL PREVAIL THRU SUNRISE AND LIKELY THRU MOST OF THE
AFTN AT KIWD/KCMX/KSAW AS LOW LEVELS REMAIN RELATIVELY DRY. SHARP
COLD FRONT CURRENTLY EXTENDING FROM SOUTHERN HUDSON BAY THRU NW MN
WILL DRIFT S...REACHING W AND NW UPPER MI LATE THIS AFTN/EVENING.
CIGS SHOULD QUICKLY FALL TO LOW MVFR AND PERHAPS IFR AT KCMX/KIWD
AFTER FROPA PER UPSTREAM OBS BEHIND FRONT. THERE MAY BE SOME SHRA OR
EVEN TSTMS IN THE VCNTY OF THE FRONT...BUT CONFIDENCE ON
COVERAGE/LOCATION OF PCPN IS LOW. FOR NOW...ONLY VCSH WAS INCLUDED IN
FCST.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 359 AM EDT TUE SEP 9 2014
THE TROUGH STRETCHED ACROSS W LAKE SUPERIOR WILL DRIFT ACROSS LAKE
SUPERIOR TODAY AS LOW PRESSURE NEARS FROM THE CENTRAL PLAINS. THE
LOW WILL BE OVER E IOWA BY DAYBREAK WEDNESDAY...AND CONTINUE TO PUSH
NE OVER E UPPER MI AND N LOWER MI LATE WEDNESDAY AFTERNOON...BEFORE
EXITING INTO QUEBEC ON THURSDAY. N GALES TO AROUND 40KTS WILL BE
POSSIBLE WEDNESDAY MORNING OVER W LAKE SUPERIOR...BEFORE SLOWLY
EXPANDING TO CENTRAL LAKE SUPERIOR WEDNESDAY EVENING THROUGH THE
OVERNIGHT HOURS. LARGE HIGH PRESSURE OVER S ALBERTA AND SASKATCHEWAN
THURSDAY WILL SINK ACROSS THE N AND CENTRAL PLAINS...WHILE BUILDING
A RIDGE ACROSS LAKE SUPERIOR THURSDAY NIGHT THROUGH SATURDAY WITH
WINDS GUSTING TO AROUND 20KTS OR LESS.
&&
.HYDROLOGY...
ISSUED AT 359 AM EDT TUE SEP 9 2014
RAINFALL TOTALS FROM TONIGHT THROUGH WEDNESDAY NIGHT ACROSS UPPER MI
RANGE FROM JUST OVER 1.5IN TO NEARLY 3IN ACROSS THE KEWEENAW
PENINSULA AND FAVORABLE UPSLOPE ENHANCED LOCATIONS OF N CENTRAL
UPPER MI. AN AREAL FLOOD WATCH REMAINS POSTED FOR MUCH OF W AND
CENTRAL UPPER MI. MUCH OF THE CWA IS IN THE DAY 2 EXCESSIVE RAINFALL
POTENTIAL OUTLOOK /SLIGHT RISK/ FOR DAY 2 /12Z WED-12Z THU/. THE
MORNING RIVER FCSTS WILL BE RAN WITH 48HR QFP VALUES...SO IT WILL BE
INTERESTING TO SEE WHAT REACTION IS EXPECTED. OUR LAST RAIN EVENT
DID NOT DO MUCH AT THE RIVER GAUGE LOCATIONS. RIVERS THAT ARE
RUNNING HIGHER /GENERALLY 1-2FT/ THAN THIS TIME LAST MONTH INCLUDE
THE SOUTH BRANCH OF THE ONTONAGON RIVER AT EWEN...THE FORD RIVER AT
HYDE...THE STURGEON RIVER AT NAHMA JUNCTION...AND THE MANISTIQUE
RIVER AT MANISTIQUE.
AT THIS POINT THE N CENTRAL RFC 3HR FLASH FLOOD GUIDANCE IS HOVERING
BETWEEN 2-3.5IN...WITH 6HR FLASH FLOOD GUIDANCE IS CLOSER TO 2.25 TO
OVER 4IN. OF COURSE IT/S VERY TERRAIN AND BASIN SPECIFIC. AS
PREVIOUSLY NOTED...MANY AREAS OF W AND CENTRAL UPPER MI ARE RUNNING
AROUND 2-4IN ABOVE THE 2 WEEK NORMAL PRECIP WISE DUE TO RECENT HEAVY
RAINFALL. EXPECT THE TRADITIONAL URBAN/SMALL STREAM FLOODING TO BE A
SIGNIFICANT POSSIBLITY IN THE TYPICAL POOR DRAINAGE AREAS OF ESC IF
RAINFALL IS STEADY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FLOOD WATCH FROM LATE TONIGHT THROUGH WEDNESDAY EVENING FOR
MIZ001>006-009>013-084.
LAKE SUPERIOR...
GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY MORNING FOR
LSZ251-267.
GALE WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY MORNING FOR
LSZ243>245-264>266.
GALE WATCH FROM WEDNESDAY MORNING THROUGH LATE WEDNESDAY NIGHT
FOR LSZ162-240>242-263.
GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY MORNING FOR
LSZ248>250.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KEC
AVIATION...ROLFSON
MARINE...KF
HYDROLOGY...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
400 AM EDT TUE SEP 9 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 402 PM EDT MON SEP 8 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A MAINLY ZONAL PATTERN ACROSS
THE NRN CONUS AND SRN CANADA. A SHORTWAVE TROUGH OVER WI AND
ASSOCIATED 700-300 MB QVECTOR CONV SUPPORTED SOME VERY LIGHT RAIN
SHOWERS OR SPINKLES OVER NRN WI INTO FAR WRN UPPER MI. WITH THE
FORCING MAINLY IN THE 500-300 MB LAYER AND RELATIVELY DRY LOW LEVELS
JUST MID LEVEL CLOUDS/CIGS WERE REPORTED WITH MOST STATIONS NOT EVEN
REPORTING ANY MEASURABLE AMOUNTS. OTHERWISE...PARLTY CLOUDY SKIES
WITH GUSTY SOUTH WINDS OF 15 TO 25 MPH PREVAILED OVER THE REST OF
THE CWA.
TONIGHT...EXPECT THE -SHRA/SPRINKLES OVER SW UPPER MI TO SLOWLY
SLIDE TO THE EAST THIS EVENING AS THE SHRTWV DEPARTS. THE LEFTOVER
MID CLOUDS SHOULD ALSO THIN OUT OVERNIGHT AS QVECTOR DIV SPREADS
INTO THE AREA. HOWEVER...WITH INCREASING SW FLOW 925-700 MB THETA-E
ADVECTION ADDITIONAL CLOUDS MAY SPREAD INTO THE WEST HALF LATE. THE
SRLY FLOW WILL KEEP MIN READINGS IN THE MID 50S INLAND TO AROUND 60
IN DOWNSLOPE LOCATIONS NEAR LAKE SUPERIOR.
TUESDAY...THE MODELS SUGGEST THAT A FRONTAL BOUNDARY WILL SLOWLY
DROP THROUGH WRN LAKE SUPERIOR AND AIDED BY THE LAKE BREEZE INTO THE
NW CWA BY AFTERNOON. THE COMBINATION OF THE APPROACHING FRONTAL
BOUNDARY...MLCAPE VALUES INTO THE 1K-2K RANGE...RELATIVELY WEAK
CAPPING AND THE POTENTIAL A WEAK SHORTWAVE BRUSHING THE AREA MAY
PRODUCE SOME ISOLD/SCT SHRA/TSRA BY MID TO LATE AFTERNOON OVER THE
WEST HALF. SINCE THE STRONGEST FORCING IS EXPECTED TO REMAIN NW OF
THE CWA...ONLY LOWER END CHANCE POPS WERE INCLUDED.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 431 PM EDT MON SEP 8 2014
THE MAIN ISSUES THIS FORECAST PERIOD WILL BE THE FLOODING POTENTIAL
TUESDAY NIGHT THROUGH WEDNESDAY MORNING...GALES ON LAKE SUPERIOR
WEDNESDAY INTO WEDNESDAY NIGHT AND COLDER THAN NORMAL TEMPERATURES
MOVING IN THURSDAY NIGHT THROUGH SATURDAY.
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...LOW PRESSURE WILL INTENSIFY
OVER THE CENTRAL PLAINS AS IT LIFTS NORTHEASTWARD TO WESTERN IOWA
LATE TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING AT OR AROUND 1000MB.
AT THE SAME TIME...AN UPPER LEVEL 500MB TROUGH AXIS SLIDES ACROSS
THE ROCKIES INTO THE PLAINS STATES. MODELS ARE IN FAIRLY GOOD
AGREEMENT...HOWEVER...THE 12Z NAM IS A BIT OF AN OUTLIER...TAKING
THE LOW FARTHER NORTH AND WEST THAN THE OTHER MODELS. SHOWERS AND
THUNDERSTORMS WILL DEVELOP AHEAD OF THE LOW PRESSURE SYSTEM ON
INCREASED MOISTURE UPGLIDE AS SHOWN ON THE 300K ISOSURFACE ALONG
WITH INCREASING MOISTURE SHOWN BY PLOTTING 1000-500 RH. THE BEST
CHANCE OF CONVECTION WOULD BE TUESDAY EVENING WITH INSTABILITY
LINGERING ON THE WARM SIDE OF THE LOW. THE LOW WILL CONTINUE
NORTHEASTWARD TO JUST SOUTH OF JAMES BAY WHILE FURTHER STRENGTHENING
TO AROUND 990MB AS THE UPPER LEVEL TROUGH SLIDES INTO THE UPPER
MISSISSIPPI VALLEY. AT THIS POINT...THE HEAVY RAINFALL POTENTIAL
WOULD BE GREATEST LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING...AS
DEEP LAYER MOISTURE WOULD BE IN PLACE AT THE SAME TIME ISENTROPIC
UPGLIDE IS MAXIMIZED AND DEEP LAYER FORCING IS MAXIMIZED AS A FAIRLY
STRONG 700MB FGEN BAND WRAPS THROUGH THE AREA. ADDITIONALLY...THE
AREA WILL LIE IN THE LEFT EXIT REGION OF A JET MAX TO THE SOUTH AND
PARTIALLY IN THE INFLUENCE OF A RIGHT ENTRANCE REGION OF A JET MAX
TO THE NORTH. ALSO IN SUPPORT OF HEAVY RAINFALL TUESDAY NIGHT
THROUGH WEDNESDAY MORNING WILL BE PWAT VALUES CONTINUING TO BE
PROGGED AT 1.5 TO 2 INCHES ON STRONG SOUTHERLY MOISTURE TRANSPORT
INTO THE REGION. RAINFALL WILL CONTINUE THROUGH WEDNESDAY
NIGHT...HOWEVER...OVERALL INTENSITY IS EXPECTED TO DECREASE AS THE
AFOREMENTIONED HEAVY RAINFALL FEATURES SHIFT OUT OF THE AREA AND
MAINLY WRAP AROUND PRECIP LINGERS OVER GENERALLY THE WESTERN U.P. AS
A DRY SLOT IS PROGGED TO WEDGE INTO THE CENTRAL AND EASTERN
AREAS...ALLOWING FOR MAINLY DRIZZLE.
HEAVY RAINFALL POTENTIAL INCLUDING AREAL FLOOD WATCH...WITH THE DEEP
MOISTURE AND LIFT EXPECTED ACROSS THE AREA...RAINFALL TOTALS WILL
LIKELY EXCEED 2 INCHES WITH UP TO 3 INCHES POSSIBLE ACROSS PORTIONS
OF THE CENTRAL AND WESTERN UPPER PENINSULA. MOST OF THE RAINFALL IS
EXPECTED TO OCCUR IN A 12 HOUR PERIOD...BETWEEN 06Z/10 AND 18Z/10.
THIS HEAVY RAINFALL WILL OCCUR ON VERY SATURATED SOILS WHICH WILL
ALLOW RUNOFF TO BEGIN QUICKLY. MANY AREAS OF THE CENTRAL AND WESTERN
PORTIONS OF THE U.P. ARE RUNNING AROUND 2 TO 4 INCHES ABOVE THE 2
WEEK NORMAL DUE TO RECENT HEAVY RAINFALL. SEVERAL RIVERS WITHIN THE
FLOOD WATCH ARE RUNNING HIGHER THAN NORMAL WITH ANY ADDITIONAL
WIDESPREAD RAINFALL EXPECTED TO INCREASE THESE LEVEL...SOME OF WHICH
MAY APPROACH FLOOD STAGE...BASED ON HEAVIER RAINFALL GUIDANCE.
OUTSIDE OF THE RAINFALL POTENTIAL...STRONG WINDS WILL ALSO BE AN
ISSUE. AS THE LOW PUSHES INTO THE REGION...A FAIRLY STRONG AREA OF
HIGH PRESSURE WILL BUILD ACROSS MUCH OF WESTERN CANADA. THE PRESSURE
GRADIENT WILL TIGHTEN BETWEEN THE TWO SYSTEMS LATE TUESDAY NIGHT AND
ESPECIALLY DURING THE DAY WEDNESDAY. THE PERIOD OF STRONGEST WINDS
ARE EXPECTED TO PUSH THROUGH THE AREA LATE WEDNESDAY MORNING THROUGH
LATE WEDNESDAY NIGHT. WINDS OVER MUCH OF THE LAND AREAS AWAY FROM
THE SHORE WILL BE SUSTAINED AROUND 15 TO 25 MPH. OVER THE LAKE...THE
KEWEENAW PENINSULA AND AREAS NEAR THE SHORE WILL SEE WINDS
SUSTAINED CLOSER TO 35 TO 40 MPH WITH GUSTS REACHING AROUND 45 TO
EVEN 50 MPH. THIS IS SUPPORTED WITH CAA ACROSS THE LAKE ON THE BACK
SIDE OF THE LOW WITH RELATIVELY WARM LAKE SURFACE TEMPERATURES
ALLOWING STRONGER WINDS TO MIX DOWN TO THE LAKE SURFACE. SOUNDINGS
SUPPORT WINDS MIXING DOWN FROM AROUND 925-900MB...WHERE WINDS ARE
PROGGED TO BE RIGHT AROUND 45 TO 50 MPH. CONFIDENCE IN HIGH WINDS IS
FAIRLY HIGH OVER THE LAKE...WITH A BIT LOWER CONFIDENCE IN THE WIND
DIRECTION. HAVE DECIDED TO GO WITH A GALE WATCH BEGINNING WEDNESDAY
MORNING INTO LATE WEDNESDAY NIGHT.
THURSDAY THROUGH FRIDAY NIGHT...THE LOW PRESSURE SYSTEM NEAR JAMES
BAY WILL CONTINUE TO SLOWLY LIFT NORTHEAST...PUSHING INTO QUEBEC BY
THURSDAY AFTERNOON. AT THE SAME TIME...STRONG HIGH PRESSURE WILL
BUILD ACROSS MUCH OF THE UPPER MISSISSIPPI VALLEY. THE PRESSURE
GRADIENT MAY LINGER THROUGH THURSDAY MORNING OVER EASTERN LAKE
SUPERIOR KEEPING GALE FORCE GUSTS IN THE FORECAST...HOWEVER...AS THE
LOW SLIPS AWAY AND THE HIGH BUILDS IN...WINDS WILL DIMINISH DURING
THE AFTERNOON HOURS THURSDAY. UPPER LEVEL TROUGHING WILL LINGER
THROUGH FRIDAY NIGHT ACROSS THE AREA WITH A COUPLE SHORTWAVES
PUSHING THROUGH. THE COOLER AIR ALOFT ASSOCIATED WITH THE TROUGH
WILL ALLOW FOR CONTINUED CLOUD COVER ALONG WITH LIGHT RAIN SHOWERS.
BY LATE FRIDAY NIGHT THE HIGH PRESSURE CENTER MOVES OVERHEAD ALONG
WITH SLIGHT RIDGING ALOFT AND DRIER AIR...ALLOWING THE PRECIP TO END
AND SKIES TO CLEAR. TEMPERATURES COULD BE QUITE COOL FRIDAY NIGHT
WITH CALM CONDITIONS...CLEARING SKIES AND PWAT VALUES AROUND 30 TO
40 PERCENT OF NORMAL. KEPT THE IDEA OF SEEING BELOW FREEZING
TEMPERATURES ACROSS INLAND AREAS OF THE U.P.
SATURDAY THROUGH MONDAY...HIGH PRESSURE IS EXPECTED TO LINGER
THROUGH SATURDAY...KEEPING CONDITIONS DRY AND SKIES MAINLY CLEAR.
TEMPERATURES WILL BEGIN TO MODERATE SUNDAY INTO MONDAY ON RETURN
SOUTHERLY FLOW ON THE WEST SIDE OF THE HIGH. THE GFS/EC HAVE ANOTHER
SYSTEM PUSHING INTO THE AREA DURING THE SUNDAY NIGHT INTO MONDAY
TIME PERIOD...HOWEVER...THERE IS QUITE A BIT OF UNCERTAINTY IN THE
TRACK OF THE SYSTEM AND THE OVERALL STRENGTH AND TIMING OF THE UPPER
LEVEL TROUGH. LEANED HEAVILY ON A CONSENSUS OF THE MODELS DURING
THIS TIME PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 121 AM EDT TUE SEP 9 2014
VFR CONDITIONS WILL PREVAIL THRU SUNRISE AND LIKELY THRU MOST OF THE
AFTN AT KIWD/KCMX/KSAW AS LOW LEVELS REMAIN RELATIVELY DRY. SHARP
COLD FRONT CURRENTLY EXTENDING FROM SOUTHERN HUDSON BAY THRU NW MN
WILL DRIFT S...REACHING W AND NW UPPER MI LATE THIS AFTN/EVENING.
CIGS SHOULD QUICKLY FALL TO LOW MVFR AND PERHAPS IFR AT KCMX/KIWD
AFTER FROPA PER UPSTREAM OBS BEHIND FRONT. THERE MAY BE SOME SHRA OR
EVEN TSTMS IN THE VCNTY OF THE FRONT...BUT CONFIDENCE ON
COVERAGE/LOCATION OF PCPN IS LOW. FOR NOW...ONLY VCSH WAS INCLUDED IN
FCST.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 359 AM EDT TUE SEP 9 2014
THE TROUGH STRETCHED ACROSS W LAKE SUPERIOR WILL DRIFT ACROSS LAKE
SUPERIOR TODAY AS LOW PRESSURE NEARS FROM THE CENTRAL PLAINS. THE
LOW WILL BE OVER E IOWA BY DAYBREAK WEDNESDAY...AND CONTINUE TO PUSH
NE OVER E UPPER MI AND N LOWER MI LATE WEDNESDAY AFTERNOON...BEFORE
EXITING INTO QUEBEC ON THURSDAY. N GALES TO AROUND 40KTS WILL BE
POSSIBLE WEDNESDAY MORNING OVER W LAKE SUPERIOR...BEFORE SLOWLY
EXPANDING TO CENTRAL LAKE SUPERIOR WEDNESDAY EVENING THROUGH THE
OVERNIGHT HOURS. LARGE HIGH PRESSURE OVER S ALBERTA AND SASKATCHEWAN
THURSDAY WILL SINK ACROSS THE N AND CENTRAL PLAINS...WHILE BUILDING
A RIDGE ACROSS LAKE SUPERIOR THURSDAY NIGHT THROUGH SATURDAY WITH
WINDS GUSTING TO AROUND 20KTS OR LESS.
&&
.HYDROLOGY...
ISSUED AT 359 AM EDT TUE SEP 9 2014
RAINFALL TOTALS FROM TONIGHT THROUGH WEDNESDAY NIGHT ACROSS UPPER MI
RANGE FROM JUST OVER 1.5IN TO NEARLY 3IN ACROSS THE KEWEENAW
PENINSULA AND FAVORABLE UPSLOPE ENHANCED LOCATIONS OF N CENTRAL
UPPER MI. AN AREAL FLOOD WATCH REMAINS POSTED FOR MUCH OF W AND
CENTRAL UPPER MI. MUCH OF THE CWA IS IN THE DAY 2 EXCESSIVE RAINFALL
POTENTIAL OUTLOOK /SLIGHT RISK/ FOR DAY 2 /12Z WED-12Z THU/. THE
MORNING RIVER FCSTS WILL BE RAN WITH 48HR QFP VALUES...SO IT WILL BE
INTERESTING TO SEE WHAT REACTION IS EXPECTED. OUR LAST RAIN EVENT
DID NOT DO MUCH AT THE RIVER GAUGE LOCATIONS. RIVERS THAT ARE
RUNNING HIGHER /GENERALLY 1-2FT/ THAN THIS TIME LAST MONTH INCLUDE
THE SOUTH BRANCH OF THE ONTONAGON RIVER AT EWEN...THE FORD RIVER AT
HYDE...THE STURGEON RIVER AT NAHMA JUNCTION...AND THE MANISTIQUE
RIVER AT MANISTIQUE.
AT THIS POINT THE N CENTRAL RFC 3HR FLASH FLOOD GUIDANCE IS HOVERING
BETWEEN 2-3.5IN...WITH 6HR FLASH FLOOD GUIDANCE IS CLOSER TO 2.25 TO
OVER 4IN. OF COURSE IT/S VERY TERRAIN AND BASIN SPECIFIC. AS
PREVIOUSLY NOTED...MANY AREAS OF W AND CENTRAL UPPER MI ARE RUNNING
AROUND 2-4IN ABOVE THE 2 WEEK NORMAL PRECIP WISE DUE TO RECENT HEAVY
RAINFALL. EXPECT THE TRADITIONAL URBAN/SMALL STREAM FLOODING TO BE A
SIGNIFICANT POSSIBLITY IN THE TYPICAL POOR DRAINAGE AREAS OF ESC IF
RAINFALL IS STEADY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FLOOD WATCH FROM LATE TONIGHT THROUGH WEDNESDAY EVENING FOR
MIZ001>006-009>013-084.
LAKE SUPERIOR...
GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY MORNING FOR
LSZ251-267.
GALE WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY MORNING FOR
LSZ243>245-264>266.
GALE WATCH FROM WEDNESDAY MORNING THROUGH LATE WEDNESDAY NIGHT
FOR LSZ162-240>242-263.
GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY MORNING FOR
LSZ248>250.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KEC
AVIATION...ROLFSON
MARINE...KF
HYDROLOGY...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
123 AM EDT TUE SEP 9 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 402 PM EDT MON SEP 8 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A MAINLY ZONAL PATTERN ACROSS
THE NRN CONUS AND SRN CANADA. A SHORTWAVE TROUGH OVER WI AND
ASSOCIATED 700-300 MB QVECTOR CONV SUPPORTED SOME VERY LIGHT RAIN
SHOWERS OR SPINKLES OVER NRN WI INTO FAR WRN UPPER MI. WITH THE
FORCING MAINLY IN THE 500-300 MB LAYER AND RELATIVELY DRY LOW LEVELS
JUST MID LEVEL CLOUDS/CIGS WERE REPORTED WITH MOST STATIONS NOT EVEN
REPORTING ANY MEASURABLE AMOUNTS. OTHERWISE...PARLTY CLOUDY SKIES
WITH GUSTY SOUTH WINDS OF 15 TO 25 MPH PREVAILED OVER THE REST OF
THE CWA.
TONIGHT...EXPECT THE -SHRA/SPRINKLES OVER SW UPPER MI TO SLOWLY
SLIDE TO THE EAST THIS EVENING AS THE SHRTWV DEPARTS. THE LEFTOVER
MID CLOUDS SHOULD ALSO THIN OUT OVERNIGHT AS QVECTOR DIV SPREADS
INTO THE AREA. HOWEVER...WITH INCREASING SW FLOW 925-700 MB THETA-E
ADVECTION ADDITIONAL CLOUDS MAY SPREAD INTO THE WEST HALF LATE. THE
SRLY FLOW WILL KEEP MIN READINGS IN THE MID 50S INLAND TO AROUND 60
IN DOWNSLOPE LOCATIONS NEAR LAKE SUPERIOR.
TUESDAY...THE MODELS SUGGEST THAT A FRONTAL BOUNDARY WILL SLOWLY
DROP THROUGH WRN LAKE SUPERIOR AND AIDED BY THE LAKE BREEZE INTO THE
NW CWA BY AFTERNOON. THE COMBINATION OF THE APPROACHING FRONTAL
BOUNDARY...MLCAPE VALUES INTO THE 1K-2K RANGE...RELATIVELY WEAK
CAPPING AND THE POTENTIAL A WEAK SHORTWAVE BRUSHING THE AREA MAY
PRODUCE SOME ISOLD/SCT SHRA/TSRA BY MID TO LATE AFTERNOON OVER THE
WEST HALF. SINCE THE STRONGEST FORCING IS EXPECTED TO REMAIN NW OF
THE CWA...ONLY LOWER END CHANCE POPS WERE INCLUDED.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 431 PM EDT MON SEP 8 2014
THE MAIN ISSUES THIS FORECAST PERIOD WILL BE THE FLOODING POTENTIAL
TUESDAY NIGHT THROUGH WEDNESDAY MORNING...GALES ON LAKE SUPERIOR
WEDNESDAY INTO WEDNESDAY NIGHT AND COLDER THAN NORMAL TEMPERATURES
MOVING IN THURSDAY NIGHT THROUGH SATURDAY.
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...LOW PRESSURE WILL INTENSIFY
OVER THE CENTRAL PLAINS AS IT LIFTS NORTHEASTWARD TO WESTERN IOWA
LATE TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING AT OR AROUND 1000MB.
AT THE SAME TIME...AN UPPER LEVEL 500MB TROUGH AXIS SLIDES ACROSS
THE ROCKIES INTO THE PLAINS STATES. MODELS ARE IN FAIRLY GOOD
AGREEMENT...HOWEVER...THE 12Z NAM IS A BIT OF AN OUTLIER...TAKING
THE LOW FARTHER NORTH AND WEST THAN THE OTHER MODELS. SHOWERS AND
THUNDERSTORMS WILL DEVELOP AHEAD OF THE LOW PRESSURE SYSTEM ON
INCREASED MOISTURE UPGLIDE AS SHOWN ON THE 300K ISOSURFACE ALONG
WITH INCREASING MOISTURE SHOWN BY PLOTTING 1000-500 RH. THE BEST
CHANCE OF CONVECTION WOULD BE TUESDAY EVENING WITH INSTABILITY
LINGERING ON THE WARM SIDE OF THE LOW. THE LOW WILL CONTINUE
NORTHEASTWARD TO JUST SOUTH OF JAMES BAY WHILE FURTHER STRENGTHENING
TO AROUND 990MB AS THE UPPER LEVEL TROUGH SLIDES INTO THE UPPER
MISSISSIPPI VALLEY. AT THIS POINT...THE HEAVY RAINFALL POTENTIAL
WOULD BE GREATEST LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING...AS
DEEP LAYER MOISTURE WOULD BE IN PLACE AT THE SAME TIME ISENTROPIC
UPGLIDE IS MAXIMIZED AND DEEP LAYER FORCING IS MAXIMIZED AS A FAIRLY
STRONG 700MB FGEN BAND WRAPS THROUGH THE AREA. ADDITIONALLY...THE
AREA WILL LIE IN THE LEFT EXIT REGION OF A JET MAX TO THE SOUTH AND
PARTIALLY IN THE INFLUENCE OF A RIGHT ENTRANCE REGION OF A JET MAX
TO THE NORTH. ALSO IN SUPPORT OF HEAVY RAINFALL TUESDAY NIGHT
THROUGH WEDNESDAY MORNING WILL BE PWAT VALUES CONTINUING TO BE
PROGGED AT 1.5 TO 2 INCHES ON STRONG SOUTHERLY MOISTURE TRANSPORT
INTO THE REGION. RAINFALL WILL CONTINUE THROUGH WEDNESDAY
NIGHT...HOWEVER...OVERALL INTENSITY IS EXPECTED TO DECREASE AS THE
AFOREMENTIONED HEAVY RAINFALL FEATURES SHIFT OUT OF THE AREA AND
MAINLY WRAP AROUND PRECIP LINGERS OVER GENERALLY THE WESTERN U.P. AS
A DRY SLOT IS PROGGED TO WEDGE INTO THE CENTRAL AND EASTERN
AREAS...ALLOWING FOR MAINLY DRIZZLE.
HEAVY RAINFALL POTENTIAL INCLUDING AREAL FLOOD WATCH...WITH THE DEEP
MOISTURE AND LIFT EXPECTED ACROSS THE AREA...RAINFALL TOTALS WILL
LIKELY EXCEED 2 INCHES WITH UP TO 3 INCHES POSSIBLE ACROSS PORTIONS
OF THE CENTRAL AND WESTERN UPPER PENINSULA. MOST OF THE RAINFALL IS
EXPECTED TO OCCUR IN A 12 HOUR PERIOD...BETWEEN 06Z/10 AND 18Z/10.
THIS HEAVY RAINFALL WILL OCCUR ON VERY SATURATED SOILS WHICH WILL
ALLOW RUNOFF TO BEGIN QUICKLY. MANY AREAS OF THE CENTRAL AND WESTERN
PORTIONS OF THE U.P. ARE RUNNING AROUND 2 TO 4 INCHES ABOVE THE 2
WEEK NORMAL DUE TO RECENT HEAVY RAINFALL. SEVERAL RIVERS WITHIN THE
FLOOD WATCH ARE RUNNING HIGHER THAN NORMAL WITH ANY ADDITIONAL
WIDESPREAD RAINFALL EXPECTED TO INCREASE THESE LEVEL...SOME OF WHICH
MAY APPROACH FLOOD STAGE...BASED ON HEAVIER RAINFALL GUIDANCE.
OUTSIDE OF THE RAINFALL POTENTIAL...STRONG WINDS WILL ALSO BE AN
ISSUE. AS THE LOW PUSHES INTO THE REGION...A FAIRLY STRONG AREA OF
HIGH PRESSURE WILL BUILD ACROSS MUCH OF WESTERN CANADA. THE PRESSURE
GRADIENT WILL TIGHTEN BETWEEN THE TWO SYSTEMS LATE TUESDAY NIGHT AND
ESPECIALLY DURING THE DAY WEDNESDAY. THE PERIOD OF STRONGEST WINDS
ARE EXPECTED TO PUSH THROUGH THE AREA LATE WEDNESDAY MORNING THROUGH
LATE WEDNESDAY NIGHT. WINDS OVER MUCH OF THE LAND AREAS AWAY FROM
THE SHORE WILL BE SUSTAINED AROUND 15 TO 25 MPH. OVER THE LAKE...THE
KEWEENAW PENINSULA AND AREAS NEAR THE SHORE WILL SEE WINDS
SUSTAINED CLOSER TO 35 TO 40 MPH WITH GUSTS REACHING AROUND 45 TO
EVEN 50 MPH. THIS IS SUPPORTED WITH CAA ACROSS THE LAKE ON THE BACK
SIDE OF THE LOW WITH RELATIVELY WARM LAKE SURFACE TEMPERATURES
ALLOWING STRONGER WINDS TO MIX DOWN TO THE LAKE SURFACE. SOUNDINGS
SUPPORT WINDS MIXING DOWN FROM AROUND 925-900MB...WHERE WINDS ARE
PROGGED TO BE RIGHT AROUND 45 TO 50 MPH. CONFIDENCE IN HIGH WINDS IS
FAIRLY HIGH OVER THE LAKE...WITH A BIT LOWER CONFIDENCE IN THE WIND
DIRECTION. HAVE DECIDED TO GO WITH A GALE WATCH BEGINNING WEDNESDAY
MORNING INTO LATE WEDNESDAY NIGHT.
THURSDAY THROUGH FRIDAY NIGHT...THE LOW PRESSURE SYSTEM NEAR JAMES
BAY WILL CONTINUE TO SLOWLY LIFT NORTHEAST...PUSHING INTO QUEBEC BY
THURSDAY AFTERNOON. AT THE SAME TIME...STRONG HIGH PRESSURE WILL
BUILD ACROSS MUCH OF THE UPPER MISSISSIPPI VALLEY. THE PRESSURE
GRADIENT MAY LINGER THROUGH THURSDAY MORNING OVER EASTERN LAKE
SUPERIOR KEEPING GALE FORCE GUSTS IN THE FORECAST...HOWEVER...AS THE
LOW SLIPS AWAY AND THE HIGH BUILDS IN...WINDS WILL DIMINISH DURING
THE AFTERNOON HOURS THURSDAY. UPPER LEVEL TROUGHING WILL LINGER
THROUGH FRIDAY NIGHT ACROSS THE AREA WITH A COUPLE SHORTWAVES
PUSHING THROUGH. THE COOLER AIR ALOFT ASSOCIATED WITH THE TROUGH
WILL ALLOW FOR CONTINUED CLOUD COVER ALONG WITH LIGHT RAIN SHOWERS.
BY LATE FRIDAY NIGHT THE HIGH PRESSURE CENTER MOVES OVERHEAD ALONG
WITH SLIGHT RIDGING ALOFT AND DRIER AIR...ALLOWING THE PRECIP TO END
AND SKIES TO CLEAR. TEMPERATURES COULD BE QUITE COOL FRIDAY NIGHT
WITH CALM CONDITIONS...CLEARING SKIES AND PWAT VALUES AROUND 30 TO
40 PERCENT OF NORMAL. KEPT THE IDEA OF SEEING BELOW FREEZING
TEMPERATURES ACROSS INLAND AREAS OF THE U.P.
SATURDAY THROUGH MONDAY...HIGH PRESSURE IS EXPECTED TO LINGER
THROUGH SATURDAY...KEEPING CONDITIONS DRY AND SKIES MAINLY CLEAR.
TEMPERATURES WILL BEGIN TO MODERATE SUNDAY INTO MONDAY ON RETURN
SOUTHERLY FLOW ON THE WEST SIDE OF THE HIGH. THE GFS/EC HAVE ANOTHER
SYSTEM PUSHING INTO THE AREA DURING THE SUNDAY NIGHT INTO MONDAY
TIME PERIOD...HOWEVER...THERE IS QUITE A BIT OF UNCERTAINTY IN THE
TRACK OF THE SYSTEM AND THE OVERALL STRENGTH AND TIMING OF THE UPPER
LEVEL TROUGH. LEANED HEAVILY ON A CONSENSUS OF THE MODELS DURING
THIS TIME PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 121 AM EDT TUE SEP 9 2014
VFR CONDITIONS WILL PREVAIL THRU SUNRISE AND LIKELY THRU MOST OF THE
AFTN AT KIWD/KCMX/KSAW AS LOW LEVELS REMAIN RELATIVELY DRY. SHARP
COLD FRONT CURRENTLY EXTENDING FROM SOUTHERN HUDSON BAY THRU NW MN
WILL DRIFT S...REACHING W AND NW UPPER MI LATE THIS AFTN/EVENING.
CIGS SHOULD QUICKLY FALL TO LOW MVFR AND PERHAPS IFR AT KCMX/KIWD
AFTER FROPA PER UPSTREAM OBS BEHIND FRONT. THERE MAY BE SOME SHRA OR
EVEN TSTMS IN THE VCNTY OF THE FRONT...BUT CONFIDENCE ON
COVERAGE/LOCATION OF PCPN IS LOW. FOR NOW...ONLY VCSH WAS INCLUDED IN
FCST.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 402 PM EDT MON SEP 8 2014
SRLY WINDS TO 20 KNOTS WILL CONTINUE TONIGHT BETWEEN HIGH PRES OVER
NEW ENGLAND AND A TROUGH FROM NW ONTARIO INTO THE NRN PLAINS.
LOOK FOR THE TROUGH TO PUSH INTO LAKE SUPERIOR ON TUESDAY...WHILE A
STRONGER LOW ORGANIZES ACROSS THE CENTRAL PLAINS. EXPECT THE
DEEPENING LOW TO SHIFT NE ACROSS WI ON WEDNESDAY...AND ACROSS E
UPPER MI AND N LOWER MI LATE WEDNESDAY AFTERNOON INTO WEDNESDAY
EVENING...BEFORE CONTINUING NE INTO QUEBEC ON THURSDAY. A PERIOD OF
N GALES IS EXPECTED FROM WED MORNING THROUGH WED NIGHT. WINDS WILL
DIMINISH THU AS HIGH PRES BUILDS FROM THE PLAINS INTO THE WRN LAKES.
&&
.HYDROLOGY...
ISSUED AT 431 PM EDT MON SEP 8 2014
HEAVY RAINFALL POTENTIAL INCLUDING AREAL FLOOD WATCH...WITH THE DEEP
MOISTURE AND LIFT EXPECTED ACROSS THE AREA...RAINFALL TOTALS WILL
LIKELY EXCEED 2 INCHES WITH UP TO 3 INCHES POSSIBLE ACROSS PORTIONS
OF THE CENTRAL AND WESTERN UPPER PENINSULA. MOST OF THE RAINFALL IS
EXPECTED TO OCCUR IN A 12 HOUR PERIOD...BETWEEN 06Z/10 AND 18Z/10.
THIS HEAVY RAINFALL WILL OCCUR ON VERY SATURATED SOILS WHICH WILL
ALLOW RUNOFF TO BEGIN QUICKLY. MANY AREAS OF THE CENTRAL AND WESTERN
PORTIONS OF THE U.P. ARE RUNNING AROUND 2 TO 4 INCHES ABOVE THE 2
WEEK NORMAL DUE TO RECENT HEAVY RAINFALL. SEVERAL RIVERS WITHIN THE
FLOOD WATCH ARE RUNNING SLIGHTLY HIGHER THAN NORMAL WITH ANY
ADDITIONAL WIDESPREAD RAINFALL EXPECTED TO INCREASE THESE
LEVEL...SOME OF WHICH MAY APPROACH FLOOD STAGE...BASED ON HEAVIER
RAINFALL GUIDANCE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FLOOD WATCH FROM LATE TONIGHT THROUGH WEDNESDAY EVENING FOR
MIZ001>006-009>013-084.
LAKE SUPERIOR...
GALE WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY MORNING FOR
LSZ243>245-264>267.
GALE WATCH FROM WEDNESDAY MORNING THROUGH LATE WEDNESDAY NIGHT
FOR LSZ162-240>242-263.
GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY MORNING FOR
LSZ248>251.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KEC
AVIATION...ROLFSON
MARINE...JLB
HYDROLOGY...KEC
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1225 PM CDT Tue Sep 9 2014
.UPDATE...
Issued at 1101 AM CDT TUE SEP 9 2014
Have issued a Flash Flood Watch for generally our northern two rows
of counties as heavy rainfall is expected overnight tonight. Latest
12Z NWP paints a healthy swath of 1-2 inches by tomorrow morning. At
this time it appears the bulk of the the precip will stay along and
north of the MO/IA state line. Isolated storms will continue for
locations mainly north of I-70 through early afternoon before more
organized activity develops between 19-21Z. We are still expecting
the later storms to be strong to severe with hail, straight line
winds and heavy rain the primary threats. If the storms can remain
somewhat discrete there would exist a threat for tornadoes, mainly
north of HWY 36 through early evening as model low level shear
profiles are supportive of rotating storms. The precip should slowly
end from northwest to southeast very late tonight into tomorrow
morning with the passage of a cold front. The exception should be our
far south central and southeast zones where showers and scattered
storms will linger well into the day on Wednesday.
&&
.DISCUSSION...
Issued at 403 AM CDT TUE SEP 9 2014
Morning radar looks mostly clear across the forecast area, with the
exception of a complex of thunderstorms currently over far eastern
Iowa. This thunderstorm complex is likely in response to a shortwave
mid level trough moving through the mid level flow. Perhaps
augmenting the mid level lift is a fairly weak low level jet around
20 kts at 850 mb. 305 K Theta E surface also indicates a decent
element of isentropic lift associated with this low level jet.
Through the night the complex has been mostly stationary, however
short range convective models indicate that it`ll make a E/SE jaunt
and perhaps clip the far northeastern zones with a few isolated to
scattered thunderstorms for the morning hours. Given that morning
convection should be relegated to the far NE corner of the CWA, have
generally backed off on PoPs for the southern and western fringes of
the CWA, holding off the best chances for rain until the late
afternoon into evening.
The focus then shifts to the afternoon for a potential severe
weather event, mainly north of Interstate 70, and especially north
of Highway 36. Through the day a potent surface trough will deepen
in far western Kansas. As this SFC low deepens a fairly strong
surface pressure gradient will form across eastern Kansas and
western Missouri. This will cause a decent push of warm air to move
northward in the form of a warm front. Currently there is a fairly
strong temperature gradient across northern Kansas and SE Nebraska,
characterized by temperatures in the middle 70s and dew points in
the upper 60s to lower 70s south of the boundary and temperatures in
the lower 60s with much lower dew points north of the boundary.
According to latest HRRR trends and the latest 06z NAM it appears
the warm front today will set up perhaps just north of the KS/NE
border arcing W/SW to E/NE across eastern Nebraska, perhaps just
north of the MO/IA border. Along this boundary there will be
strongly backed surface and low level winds, contributing to strong
wind profile curvature with height. With the good surge of gulf
moisture into the area, along with cooling temperatures aloft, models
currently prog afternoon instability to range between 2000 and 3000
J/Kg of surface based CAPE. One big caveat regarding afternoon
destabilization will be whether mid level clouds and any associated
elevated convection will cause enough cloud cover to mitigate surface
heating. But for now will proceed with the expectation that surface
based convection will be possible later this afternoon and that there
will be ample instability to produce robust updrafts.
As mentioned earlier the warm frontal boundary is expected to set up
just to the north of the forecast area, but that will put the area
in the warm sector with strongly backed surface and low level winds.
Aloft, mid level flow will be SW around 50 kts, causing a good
veering-with-height wind profile. Convection associated with the
boundary and low level jet will have a much better chance to occur
north of HWY 36 across far NE Kansas and SE Nebraska. Helping the
convection form will be a shortwave trough with plenty of mid level
ascent, expected to move across eastern Nebraska. This trough could
cause numerous thunderstorms across eastern Nebraska and western
Iowa, perhaps causing the severe weather event to become less
discreet and more linear with numerous storm interactions. Since the
best lift will take place further north the area will see only a
modest influence from the wave. This will act to mitigate convective
development farther south, toward Interstate 70. There could still be
enough glancing energy to cause an isolated storm or two to form as
far south as I-70, but again the best chances for these storms will
be north of KC metro. Should a storm get going in the area, the
aforementioned instability, along with deep layer shear of around 40
to 50 kts will allow for supercell structures. As the afternoon turns
to evening the low level jet will crank up to around 30 to 40 kts,
which will cause low level wind profiles to veer with height, causing
elongated hodographs. The parameters will be adequate for storms to
be strong to severe, with supercell structures possible, introducing the
possibility for all hazards of severe weather including wind, hail,
and perhaps a tornado or two, mainly north of HWY 36 toward the
KS/NE/IA border area. As storms continue to merge through the night
and cold pools interact, expect one or more bowing segments as the
low level jet veer to the SW overnight. Of concern with any bowing
segments will be forecast low level SRH to be on the order of 300 to
400 J/kg of 0-1 SRH, bringing in the possibility for
mesovortex/enhanced wind along the leading edge of any bowing
segments. This will also bring one or more complexes of thunderstorms
across northern Missouri, perhaps as far south as I-70 through the
overnight hours. The main hazard with this overnight thunderstorm
activity will be heavy rain and perhaps an isolated flooding/flash
flooding threat to far northern Missouri.
Through all this, the synoptic cold front, associated with the
surface low will remain off to the west, and likely won`t make it
into the forecast area until late Tuesday night into early Wednesday
morning. Expect some convection along this front, especially if it
fails to clear the area by the time insolation occurs on Wednesday.
A few storms could be strong, mainly across central and eastern
Missouri, as the front moves through.
The first blast of cool air will settle into the area behind the
cold front, as temperatures through mid to late week will drop to
the 60s and 70s for highs and 40s to 50s for lows. Models then prog
another fairly potent trough to make its way through the area for
the Friday/Sat time period, but with low moisture content in the
atmosphere it will be tough to generate much instability, so any
rain associated with this late-week trough should be light and
non-convective in nature. The second blast of reinforcing cold air
will then push into the area for the weekend, bringing highs 50s and
60s, and lows into the 40s and 50s. Saturday morning, once the
surface high settles into the area behind the cold front,
temperatures across far northern Missouri could drop into the 30s.
For now, not anticipating any frost headlines, but will continue to
monitor, and should FCST temps go into the lower or middle 30s frost
headlines might be needed. By Sunday and Monday the surface high will
be east of the area and southerly return flow will cause a warm up
back toward seasonal normals.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday Afternoon)
Issued at 1216 PM CDT TUE SEP 9 2014
Thunderstorms are expected to impact the terminals later this
afternoon and overnight tonight. Uncertainty exists as to how long to
keep TSRA in the TAFS, but at this time believe the first of what
should be two rounds of precip was placed in a TEMPO. Will amend TAFs
once storms develop to better time them out. VCTS is very possible
well into the night ahead of a cold front that will slowly move in
from the northwest and produce a quick wind shift out of the northwest
by mid-morning Wednesday.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...FLASH FLOOD WATCH from 7 PM CDT this evening through Wednesday
morning FOR MOZ001>008-011>017.
&&
$$
UPDATE...Pietrycha
DISCUSSION...Leighton
AVIATION...Pietrycha
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1200 PM CDT Tue Sep 9 2014
.SHORT TERM: (Through Late This Afternoon)
Issued at 320 AM CDT Tue Sep 9 2014
A MCS has been going on across eastern IA and northwestern IL for a
good part of the overnight and the forward flank of it is
propagating slowly east-southeast. Further south over our region,
southerly surface flow prevailed, and thanks to areas of clouds, are
keeping temps much warmer than where they were 24 hours ago, with
readings hovering near 70 in many locales.
Models not doing a very good job with handling the MCS to our north,
although the HRRR is about the most believable. The main flow and
Corfidi vectors suggest this MCS will still mainly propagate E-SE
with the main body remaining to the north of our region, but this is
kicking off an outflow and with a weak lo level jet nosing into
northeast MO, cannot rule out some sunrise surprise in the way of
widely scattered TSRA. The outflow dropping south may further
enable TSRA development into central IL heading deeper into the
morning and remain thru the afternoon, expanding westward into
northern MO.
As the heating of the day kicks in by midday, much of our region to
the west of STL will be in a weak CINH, very high moisture
environment and may be able to fire off isolated to scattered TSRA
during the afternoon. Rain chances look less likely into southern
IL, depending on how the MCS to the north actually evolves.
Due to all of the dependencies on clouds and rain chances, it will
be hard to get a firm handle on temps today. A MOS blend looks like
a reasonably good start, with above normal temps for many areas as
readings in the 80s are attained.
TES
.LONG TERM: (Tonight through Monday)
Issued at 347 AM CDT Tue Sep 9 2014
Primary concern remains upcoming potential for heavy rain tonight
into Wednesday. The longwave trof over the western CONUS will
continue to deepen and move east tonight. The leading edge of the
trof should be out over the eastern Plains by 00Z which will force
lee-side cyclogenesis back over the Colorado/Kansas border. The low
level jet ahead of the developing low level system system will
increase to 50-60kts resulting in impressive moisture transport from
the southeast. GFS and NAM both show a tremendous amount of
moisture convergence over northern Missouri/southern Iowa on the
nose of the low level jet tonight. The exact placement of the
heaviest rain is still in question with the GFS being further south
into our area, and the NAM being further north in Iowa. A deep
warm-cloud layer and P-wats over 2.3 inches will certainly provide a
rich environment for heavy rain. However, the SREF seems to agree
more with the NAM, as do the ARW and NMM WRF models. Will therefore
hold off issuing any flooding headlines and let the day shift take
another look.
Guidance is in decent agreement in pushing the surface front through
the area Wednesday afternoon. The low level jet ahead of the front
does diminish somewhat, but all models continue to show a 30-50kt
jet through much of the day with moisture convergence continuing
over the area. Think there will be ongoing precip ahead of the
front, tho areal coverage is somewhat uncertain. However, any
sunshine should allow for a rapid warm up in southwest flow and
18-20C temperatures at 850mb. Therefore stuck pretty close to MOS
highs in spite of potential for a lot of cloud cover and rain
through the day. Storms should form up into a line ahead of the
front in the afternoon and move south of the area by mid-late
evening. Still think there is a decent chance for some of the
storms to be severe given the strong winds aloft and the possibility
that downdrafts could mix these winds to the surface.
Much cooler air will filter into the area and behind the front for
Thursday. Temperatures will fall below normal, and are expected to
stay below normal through Monday. Highs through the period will
mainly be in the mid 60s to around 70 with lows as low as the low to
mid 40s. This will be 15-20 degrees below normal for
mid-September. The only significant chance for precipitation beyond
Wednesday evening looks to be on Friday when another shortwave dives
southeast out of the northern Plains across the Midwest.
Carney
&&
.AVIATION: (For the 18z TAFs through 18z Wednesday Afternoon)
Issued at 1130 AM CDT Tue Sep 9 2014
Scattered convection continues to develop near UIN just northeast
of warm front extending from just north of IRK southeast to just
north of STL. There will likely be more widely scattered
convection this afternoon further south as the atmosphere
destabilizes due to daytime heating which could impact the other
taf sites as well. May include VCTS at the other taf sites with a
tempo group for TSRA in the UIN taf this afternoon. New convective
development is expected tonight as a strong swly low level jet
develops over eastern KS, northwest MO and southwest IA. This will
likely lead to a convective complex which will develop across IA
and drop southeastward into UIN and COU late tonight, then
eventually make it into the St Louis metro area by early morning
as it gradually weakens. S-sely surface winds will continue this
afternoon and tonight, then veer around to a swly direction
Wednesday morning ahead of an approaching cold front.
Specifics for KSTL: There may be isolated to widely scattered
showers/storms late this afternoon as the atmosphere continues to
destabilize due to daytime heating. May include VCTS in the STL
taf late this afternoon. Weakening nocturnal convection will
likely drop southeastward into the STL area Wednesday morning. A
final round of stronger convection should impact STL late
Wednesday afternoon as a strong cold front moves southeastward
through the area. S-sely surface wind can be expected this
afternoon and tonight, then veer around to a swly direction on
Wednesday as a cold front approaches.
GKS
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1122 AM CDT Tue Sep 9 2014
.UPDATE...
Issued at 1101 AM CDT TUE SEP 9 2014
Have issued a Flash Flood Watch for generally our northern two rows
of counties as heavy rainfall is expected overnight tonight. Latest
12Z NWP paints a healthy swath of 1-2 inches by tomorrow morning. At
this time it appears the bulk of the the precip will stay along and
north of the MO/IA state line. Isolated storms will continue for
locations mainly north of I-70 through early afternoon before more
organized activity develops between 19-21Z. We are still expecting
the later storms to be strong to severe with hail, straight line
winds and heavy rain the primary threats. If the storms can remain
somewhat discrete there would exist a threat for tornadoes, mainly
north of HWY 36 through early evening as model low level shear
profiles are supportive of rotating storms. The precip should slowly
end from northwest to southeast very late tonight into tomorrow
morning with the passage of a cold front. The exception should be our
far south central and southeast zones where showers and scattered
storms will linger well into the day on Wednesday.
&&
.DISCUSSION...
Issued at 403 AM CDT TUE SEP 9 2014
Morning radar looks mostly clear across the forecast area, with the
exception of a complex of thunderstorms currently over far eastern
Iowa. This thunderstorm complex is likely in response to a shortwave
mid level trough moving through the mid level flow. Perhaps
augmenting the mid level lift is a fairly weak low level jet around
20 kts at 850 mb. 305 K Theta E surface also indicates a decent
element of isentropic lift associated with this low level jet.
Through the night the complex has been mostly stationary, however
short range convective models indicate that it`ll make a E/SE jaunt
and perhaps clip the far northeastern zones with a few isolated to
scattered thunderstorms for the morning hours. Given that morning
convection should be relegated to the far NE corner of the CWA, have
generally backed off on PoPs for the southern and western fringes of
the CWA, holding off the best chances for rain until the late
afternoon into evening.
The focus then shifts to the afternoon for a potential severe
weather event, mainly north of Interstate 70, and especially north
of Highway 36. Through the day a potent surface trough will deepen
in far western Kansas. As this SFC low deepens a fairly strong
surface pressure gradient will form across eastern Kansas and
western Missouri. This will cause a decent push of warm air to move
northward in the form of a warm front. Currently there is a fairly
strong temperature gradient across northern Kansas and SE Nebraska,
characterized by temperatures in the middle 70s and dew points in
the upper 60s to lower 70s south of the boundary and temperatures in
the lower 60s with much lower dew points north of the boundary.
According to latest HRRR trends and the latest 06z NAM it appears
the warm front today will set up perhaps just north of the KS/NE
border arcing W/SW to E/NE across eastern Nebraska, perhaps just
north of the MO/IA border. Along this boundary there will be
strongly backed surface and low level winds, contributing to strong
wind profile curvature with height. With the good surge of gulf
moisture into the area, along with cooling temperatures aloft, models
currently prog afternoon instability to range between 2000 and 3000
J/Kg of surface based CAPE. One big caveat regarding afternoon
destabilization will be whether mid level clouds and any associated
elevated convection will cause enough cloud cover to mitigate surface
heating. But for now will proceed with the expectation that surface
based convection will be possible later this afternoon and that there
will be ample instability to produce robust updrafts.
As mentioned earlier the warm frontal boundary is expected to set up
just to the north of the forecast area, but that will put the area
in the warm sector with strongly backed surface and low level winds.
Aloft, mid level flow will be SW around 50 kts, causing a good
veering-with-height wind profile. Convection associated with the
boundary and low level jet will have a much better chance to occur
north of HWY 36 across far NE Kansas and SE Nebraska. Helping the
convection form will be a shortwave trough with plenty of mid level
ascent, expected to move across eastern Nebraska. This trough could
cause numerous thunderstorms across eastern Nebraska and western
Iowa, perhaps causing the severe weather event to become less
discreet and more linear with numerous storm interactions. Since the
best lift will take place further north the area will see only a
modest influence from the wave. This will act to mitigate convective
development farther south, toward Interstate 70. There could still be
enough glancing energy to cause an isolated storm or two to form as
far south as I-70, but again the best chances for these storms will
be north of KC metro. Should a storm get going in the area, the
aforementioned instability, along with deep layer shear of around 40
to 50 kts will allow for supercell structures. As the afternoon turns
to evening the low level jet will crank up to around 30 to 40 kts,
which will cause low level wind profiles to veer with height, causing
elongated hodographs. The parameters will be adequate for storms to
be strong to severe, with supercell structures possible, introducing the
possibility for all hazards of severe weather including wind, hail,
and perhaps a tornado or two, mainly north of HWY 36 toward the
KS/NE/IA border area. As storms continue to merge through the night
and cold pools interact, expect one or more bowing segments as the
low level jet veer to the SW overnight. Of concern with any bowing
segments will be forecast low level SRH to be on the order of 300 to
400 J/kg of 0-1 SRH, bringing in the possibility for
mesovortex/enhanced wind along the leading edge of any bowing
segments. This will also bring one or more complexes of thunderstorms
across northern Missouri, perhaps as far south as I-70 through the
overnight hours. The main hazard with this overnight thunderstorm
activity will be heavy rain and perhaps an isolated flooding/flash
flooding threat to far northern Missouri.
Through all this, the synoptic cold front, associated with the
surface low will remain off to the west, and likely won`t make it
into the forecast area until late Tuesday night into early Wednesday
morning. Expect some convection along this front, especially if it
fails to clear the area by the time insolation occurs on Wednesday.
A few storms could be strong, mainly across central and eastern
Missouri, as the front moves through.
The first blast of cool air will settle into the area behind the
cold front, as temperatures through mid to late week will drop to
the 60s and 70s for highs and 40s to 50s for lows. Models then prog
another fairly potent trough to make its way through the area for
the Friday/Sat time period, but with low moisture content in the
atmosphere it will be tough to generate much instability, so any
rain associated with this late-week trough should be light and
non-convective in nature. The second blast of reinforcing cold air
will then push into the area for the weekend, bringing highs 50s and
60s, and lows into the 40s and 50s. Saturday morning, once the
surface high settles into the area behind the cold front,
temperatures across far northern Missouri could drop into the 30s.
For now, not anticipating any frost headlines, but will continue to
monitor, and should FCST temps go into the lower or middle 30s frost
headlines might be needed. By Sunday and Monday the surface high will
be east of the area and southerly return flow will cause a warm up
back toward seasonal normals.
&&
.AVIATION...(For the 12Z TAFS through 12Z Wednesday Morning)
Issued at 633 AM CDT TUE SEP 9 2014
Showers and thunderstorms will be possible later this afternoon.
Timing and duration of these storms is a bit uncertain, but this
forecast package indicates the latest thinking regarding that timing.
Expect a period of thunderstorms to move through the terminals later
today, but thunderstorms probably won`t completely be a non-threat to
the terminals through the evening. While a 06z line indicates an end
to the vicinity showers it`s possible that lingering storm activity
will last off and on through the rest of the forecast period. Expect
a frontal passage shortly after the forecast period in this package.
More showers will be possible along that frontal passage.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...FLASH FLOOD WATCH from 7 PM CDT this evening through Wednesday
morning FOR MOZ001>008-011>017.
&&
$$
UPDATE...Pietrycha
DISCUSSION...Leighton
AVIATION...Leighton
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
637 AM CDT Tue Sep 9 2014
.DISCUSSION...
Issued at 403 AM CDT TUE SEP 9 2014
Morning radar looks mostly clear across the forecast area, with the
exception of a complex of thunderstorms currently over far eastern
Iowa. This thunderstorm complex is likely in response to a shortwave
mid level trough moving through the mid level flow. Perhaps
augmenting the mid level lift is a fairly weak low level jet around
20 kts at 850 mb. 305 K Theta E surface also indicates a decent
element of isentropic lift associated with this low level jet.
Through the night the complex has been mostly stationary, however
short range convective models indicate that it`ll make a E/SE jaunt
and perhaps clip the far northeastern zones with a few isolated to
scattered thunderstorms for the morning hours. Given that morning
convection should be relegated to the far NE corner of the CWA, have
generally backed off on PoPs for the southern and western fringes of
the CWA, holding off the best chances for rain until the late
afternoon into evening.
The focus then shifts to the afternoon for a potential severe
weather event, mainly north of Interstate 70, and especially north
of Highway 36. Through the day a potent surface trough will deepen
in far western Kansas. As this SFC low deepens a fairly strong
surface pressure gradient will form across eastern Kansas and
western Missouri. This will cause a decent push of warm air to move
northward in the form of a warm front. Currently there is a fairly
strong temperature gradient across northern Kansas and SE Nebraska,
characterized by temperatures in the middle 70s and dew points in
the upper 60s to lower 70s south of the boundary and temperatures in
the lower 60s with much lower dew points north of the boundary.
According to latest HRRR trends and the latest 06z NAM it appears
the warm front today will set up perhaps just north of the KS/NE
border arcing W/SW to E/NE across eastern Nebraska, perhaps just
north of the MO/IA border. Along this boundary there will be
strongly backed surface and low level winds, contributing to strong
wind profile curvature with height. With the good surge of gulf
moisture into the area, along with cooling temperatures aloft, models
currently prog afternoon instability to range between 2000 and 3000
J/Kg of surface based CAPE. One big caveat regarding afternoon
destabilization will be whether mid level clouds and any associated
elevated convection will cause enough cloud cover to mitigate surface
heating. But for now will proceed with the expectation that surface
based convection will be possible later this afternoon and that there
will be ample instability to produce robust updrafts.
As mentioned earlier the warm frontal boundary is expected to set up
just to the north of the forecast area, but that will put the area
in the warm sector with strongly backed surface and low level winds.
Aloft, mid level flow will be SW around 50 kts, causing a good
veering-with-height wind profile. Convection associated with the
boundary and low level jet will have a much better chance to occur
north of HWY 36 across far NE Kansas and SE Nebraska. Helping the
convection form will be a shortwave trough with plenty of mid level
ascent, expected to move across eastern Nebraska. This trough could
cause numerous thunderstorms across eastern Nebraska and western
Iowa, perhaps causing the severe weather event to become less
discreet and more linear with numerous storm interactions. Since the
best lift will take place further north the area will see only a
modest influence from the wave. This will act to mitigate convective
development farther south, toward Interstate 70. There could still be
enough glancing energy to cause an isolated storm or two to form as
far south as I-70, but again the best chances for these storms will
be north of KC metro. Should a storm get going in the area, the
aforementioned instability, along with deep layer shear of around 40
to 50 kts will allow for supercell structures. As the afternoon turns
to evening the low level jet will crank up to around 30 to 40 kts,
which will cause low level wind profiles to veer with height, causing
elongated hodographs. The parameters will be adequate for storms to
be strong to severe, with supercell structures possible, introducing the
possibility for all hazards of severe weather including wind, hail,
and perhaps a tornado or two, mainly north of HWY 36 toward the
KS/NE/IA border area. As storms continue to merge through the night
and cold pools interact, expect one or more bowing segments as the
low level jet veer to the SW overnight. Of concern with any bowing
segments will be forecast low level SRH to be on the order of 300 to
400 J/kg of 0-1 SRH, bringing in the possibility for
mesovortex/enhanced wind along the leading edge of any bowing
segments. This will also bring one or more complexes of thunderstorms
across northern Missouri, perhaps as far south as I-70 through the
overnight hours. The main hazard with this overnight thunderstorm
activity will be heavy rain and perhaps an isolated flooding/flash
flooding threat to far northern Missouri.
Through all this, the synoptic cold front, associated with the
surface low will remain off to the west, and likely won`t make it
into the forecast area until late Tuesday night into early Wednesday
morning. Expect some convection along this front, especially if it
fails to clear the area by the time insolation occurs on Wednesday.
A few storms could be strong, mainly across central and eastern
Missouri, as the front moves through.
The first blast of cool air will settle into the area behind the
cold front, as temperatures through mid to late week will drop to
the 60s and 70s for highs and 40s to 50s for lows. Models then prog
another fairly potent trough to make its way through the area for
the Friday/Sat time period, but with low moisture content in the
atmosphere it will be tough to generate much instability, so any
rain associated with this late-week trough should be light and
non-convective in nature. The second blast of reinforcing cold air
will then push into the area for the weekend, bringing highs 50s and
60s, and lows into the 40s and 50s. Saturday morning, once the
surface high settles into the area behind the cold front,
temperatures across far northern Missouri could drop into the 30s.
For now, not anticipating any frost headlines, but will continue to
monitor, and should FCST temps go into the lower or middle 30s frost
headlines might be needed. By Sunday and Monday the surface high will
be east of the area and southerly return flow will cause a warm up
back toward seasonal normals.
&&
.AVIATION...(For the 12Z TAFS through 12Z Wednesday Morning)
Issued at 633 AM CDT TUE SEP 9 2014
Showers and thunderstorms will be possible later this afternoon.
Timing and duration of these storms is a bit uncertain, but this
forecast package indicates the latest thinking regarding that timing.
Expect a period of thunderstorms to move through the terminals later
today, but thunderstorms probably won`t completely be a non-threat to
the terminals through the evening. While a 06z line indicates an end
to the vicinity showers it`s possible that lingering storm activity
will last off and on through the rest of the forecast period. Expect
a frontal passage shortly after the forecast period in this package.
More showers will be possible along that frontal passage.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
DISCUSSION...Leighton
AVIATION...Leighton
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
612 AM CDT Tue Sep 9 2014
.SHORT TERM: (Through Late This Afternoon)
Issued at 320 AM CDT Tue Sep 9 2014
A MCS has been going on across eastern IA and northwestern IL for a
good part of the overnight and the forward flank of it is
propagating slowly east-southeast. Further south over our region,
southerly surface flow prevailed, and thanks to areas of clouds, are
keeping temps much warmer than where they were 24 hours ago, with
readings hovering near 70 in many locales.
Models not doing a very good job with handling the MCS to our north,
although the HRRR is about the most believable. The main flow and
Corfidi vectors suggest this MCS will still mainly propagate E-SE
with the main body remaining to the north of our region, but this is
kicking off an outflow and with a weak lo level jet nosing into
northeast MO, cannot rule out some sunrise surprise in the way of
widely scattered TSRA. The outflow dropping south may further
enable TSRA development into central IL heading deeper into the
morning and remain thru the afternoon, expanding westward into
northern MO.
As the heating of the day kicks in by midday, much of our region to
the west of STL will be in a weak CINH, very high moisture
environment and may be able to fire off isolated to scattered TSRA
during the afternoon. Rain chances look less likely into southern
IL, depending on how the MCS to the north actually evolves.
Due to all of the dependencies on clouds and rain chances, it will
be hard to get a firm handle on temps today. A MOS blend looks like
a reasonably good start, with above normal temps for many areas as
readings in the 80s are attained.
TES
.LONG TERM: (Tonight through Monday)
Issued at 347 AM CDT Tue Sep 9 2014
Primary concern remains upcoming potential for heavy rain tonight
into Wednesday. The longwave trof over the western CONUS will
continue to deepen and move east tonight. The leading edge of the
trof should be out over the eastern Plains by 00Z which will force
lee-side cyclogenesis back over the Colorado/Kansas border. The low
level jet ahead of the developing low level system system will
increase to 50-60kts resulting in impressive moisture transport from
the southeast. GFS and NAM both show a tremendous amount of
moisture convergence over northern Missouri/southern Iowa on the
nose of the low level jet tonight. The exact placement of the
heaviest rain is still in question with the GFS being further south
into our area, and the NAM being further north in Iowa. A deep
warm-cloud layer and P-wats over 2.3 inches will certainly provide a
rich environment for heavy rain. However, the SREF seems to agree
more with the NAM, as do the ARW and NMM WRF models. Will therefore
hold off issuing any flooding headlines and let the day shift take
another look.
Guidance is in decent agreement in pushing the surface front through
the area Wednesday afternoon. The low level jet ahead of the front
does diminish somewhat, but all models continue to show a 30-50kt
jet through much of the day with moisture convergence continuing
over the area. Think there will be ongoing precip ahead of the
front, tho areal coverage is somewhat uncertain. However, any
sunshine should allow for a rapid warm up in southwest flow and
18-20C temperatures at 850mb. Therefore stuck pretty close to MOS
highs in spite of potential for a lot of cloud cover and rain
through the day. Storms should form up into a line ahead of the
front in the afternoon and move south of the area by mid-late
evening. Still think there is a decent chance for some of the
storms to be severe given the strong winds aloft and the possibility
that downdrafts could mix these winds to the surface.
Much cooler air will filter into the area and behind the front for
Thursday. Temperatures will fall below normal, and are expected to
stay below normal through Monday. Highs through the period will
mainly be in the mid 60s to around 70 with lows as low as the low to
mid 40s. This will be 15-20 degrees below normal for
mid-September. The only significant chance for precipitation beyond
Wednesday evening looks to be on Friday when another shortwave dives
southeast out of the northern Plains across the Midwest.
Carney
&&
.AVIATION: (For the 12z TAFs through 12z Wednesday Morning)
Issued at 611 AM CDT Tue Sep 9 2014
VFR conditions are expected outside of TSRA along with southerly
surface winds thru the valid period. A period of TSRA should get
close to UIN this morning enough for VCTS. Elsewhere for the rest
of the day, chances look pretty sparse--enough for a mention in
the public forecast but not enough for a terminal point forecast.
The main show for rain gets going later this evening and will
mainly affect UIN, but to a lesser extent COU, and should hold off
sufficiently to the north and west of STL Metro to prevent a
mention in the forecast for now. A 45kt low level jet will get
going over a COU-UIN axis late tonight, but it also coincides with
decent coverage in TSRA in these areas and so any LLWS mention would
be redundant with shear implied in TSRA.
Specifics for KSTL: VFR and southerly winds thru the valid period
outside of TSRA. While there will be a TSRA threat in the
afternoon, it looks too small to warrant a mention. The better
rain chances should hold off until Wednesday morning.
TES
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
410 AM CDT Tue Sep 9 2014
.DISCUSSION...
Issued at 403 AM CDT TUE SEP 9 2014
Morning radar looks mostly clear across the forecast area, with the
exception of a complex of thunderstorms currently over far eastern
Iowa. This thunderstorm complex is likely in response to a shortwave
mid level trough moving through the mid level flow. Perhaps
augmenting the mid level lift is a fairly weak low level jet around
20 kts at 850 mb. 305 K Theta E surface also indicates a decent
element of isentropic lift associated with this low level jet.
Through the night the complex has been mostly stationary, however
short range convective models indicate that it`ll make a E/SE jaunt
and perhaps clip the far northeastern zones with a few isolated to
scattered thunderstorms for the morning hours. Given that morning
convection should be relegated to the far NE corner of the CWA, have
generally backed off on PoPs for the southern and western fringes of
the CWA, holding off the best chances for rain until the late
afternoon into evening.
The focus then shifts to the afternoon for a potential severe
weather event, mainly north of Interstate 70, and especially north
of Highway 36. Through the day a potent surface trough will deepen
in far western Kansas. As this SFC low deepens a fairly strong
surface pressure gradient will form across eastern Kansas and
western Missouri. This will cause a decent push of warm air to move
northward in the form of a warm front. Currently there is a fairly
strong temperature gradient across northern Kansas and SE Nebraska,
characterized by temperatures in the middle 70s and dew points in
the upper 60s to lower 70s south of the boundary and temperatures in
the lower 60s with much lower dew points north of the boundary.
According to latest HRRR trends and the latest 06z NAM it appears
the warm front today will set up perhaps just north of the KS/NE
border arcing W/SW to E/NE across eastern Nebraska, perhaps just
north of the MO/IA border. Along this boundary there will be
strongly backed surface and low level winds, contributing to strong
wind profile curvature with height. With the good surge of gulf
moisture into the area, along with cooling temperatures aloft, models
currently prog afternoon instability to range between 2000 and 3000
J/Kg of surface based CAPE. One big caveat regarding afternoon
destabilization will be whether mid level clouds and any associated
elevated convection will cause enough cloud cover to mitigate surface
heating. But for now will proceed with the expectation that surface
based convection will be possible later this afternoon and that there
will be ample instability to produce robust updrafts.
As mentioned earlier the warm frontal boundary is expected to set up
just to the north of the forecast area, but that will put the area
in the warm sector with strongly backed surface and low level winds.
Aloft, mid level flow will be SW around 50 kts, causing a good
veering-with-height wind profile. Convection associated with the
boundary and low level jet will have a much better chance to occur
north of HWY 36 across far NE Kansas and SE Nebraska. Helping the
convection form will be a shortwave trough with plenty of mid level
ascent, expected to move across eastern Nebraska. This trough could
cause numerous thunderstorms across eastern Nebraska and western
Iowa, perhaps causing the severe weather event to become less
discreet and more linear with numerous storm interactions. Since the
best lift will take place further north the area will see only a
modest influence from the wave. This will act to mitigate convective
development farther south, toward Interstate 70. There could still be
enough glancing energy to cause an isolated storm or two to form as
far south as I-70, but again the best chances for these storms will
be north of KC metro. Should a storm get going in the area, the
aforementioned instability, along with deep layer shear of around 40
to 50 kts will allow for supercell structures. As the afternoon turns
to evening the low level jet will crank up to around 30 to 40 kts,
which will cause low level wind profiles to veer with height, causing
elongated hodographs. The parameters will be adequate for storms to
be strong to severe, with supercell structures possible, introducing the
possibility for all hazards of severe weather including wind, hail,
and perhaps a tornado or two, mainly north of HWY 36 toward the
KS/NE/IA border area. As storms continue to merge through the night
and cold pools interact, expect one or more bowing segments as the
low level jet veer to the SW overnight. Of concern with any bowing
segments will be forecast low level SRH to be on the order of 300 to
400 J/kg of 0-1 SRH, bringing in the possibility for
mesovortex/enhanced wind along the leading edge of any bowing
segments. This will also bring one or more complexes of thunderstorms
across northern Missouri, perhaps as far south as I-70 through the
overnight hours. The main hazard with this overnight thunderstorm
activity will be heavy rain and perhaps an isolated flooding/flash
flooding threat to far northern Missouri.
Through all this, the synoptic cold front, associated with the
surface low will remain off to the west, and likely won`t make it
into the forecast area until late Tuesday night into early Wednesday
morning. Expect some convection along this front, especially if it
fails to clear the area by the time insolation occurs on Wednesday.
A few storms could be strong, mainly across central and eastern
Missouri, as the front moves through.
The first blast of cool air will settle into the area behind the
cold front, as temperatures through mid to late week will drop to
the 60s and 70s for highs and 40s to 50s for lows. Models then prog
another fairly potent trough to make its way through the area for
the Friday/Sat time period, but with low moisture content in the
atmosphere it will be tough to generate much instability, so any
rain associated with this late-week trough should be light and
non-convective in nature. The second blast of reinforcing cold air
will then push into the area for the weekend, bringing highs 50s and
60s, and lows into the 40s and 50s. Saturday morning, once the
surface high settles into the area behind the cold front,
temperatures across far northern Missouri could drop into the 30s.
For now, not anticipating any frost headlines, but will continue to
monitor, and should FCST temps go into the lower or middle 30s frost
headlines might be needed. By Sunday and Monday the surface high will
be east of the area and southerly return flow will cause a warm up
back toward seasonal normals.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday Night)
Issued at 1052 PM CDT MON SEP 8 2014
Complex second-half of the TAF forecast with modest uncertainty.
Increasing chances of sct precipitation expected by late morning,
with much better chances by afternoon. Kept VFR for now, but could
certainty fall to MVFR or lower depending on robustness/coverage of
convection at terminal after 20Z. Should see winds back some by
afternoon/evening as surface low deepens and moves closer.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
DISCUSSION...Leighton
AVIATION...Blair
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
348 AM CDT Tue Sep 9 2014
.SHORT TERM: (Through Late This Afternoon)
Issued at 320 AM CDT Tue Sep 9 2014
A MCS has been going on across eastern IA and northwestern IL for a
good part of the overnight and the forward flank of it is
propagating slowly east-southeast. Further south over our region,
southerly surface flow prevailed, and thanks to areas of clouds, are
keeping temps much warmer than where they were 24 hours ago, with
readings hovering near 70 in many locales.
Models not doing a very good job with handling the MCS to our north,
although the HRRR is about the most believable. The main flow and
Corfidi vectors suggest this MCS will still mainly propagate E-SE
with the main body remaining to the north of our region, but this is
kicking off an outflow and with a weak lo level jet nosing into
northeast MO, cannot rule out some sunrise surprise in the way of
widely scattered TSRA. The outflow dropping south may further
enable TSRA development into central IL heading deeper into the
morning and remain thru the afternoon, expanding westward into
northern MO.
As the heating of the day kicks in by midday, much of our region to
the west of STL will be in a weak CINH, very high moisture
environment and may be able to fire off isolated to scattered TSRA
during the afternoon. Rain chances look less likely into southern
IL, depending on how the MCS to the north actually evolves.
Due to all of the dependencies on clouds and rain chances, it will
be hard to get a firm handle on temps today. A MOS blend looks like
a reasonably good start, with above normal temps for many areas as
readings in the 80s are attained.
TES
.LONG TERM: (Tonight through Monday)
Issued at 347 AM CDT Tue Sep 9 2014
Primary concern remains upcoming potential for heavy rain tonight
into Wednesday. The longwave trof over the western CONUS will
continue to deepen and move east tonight. The leading edge of the
trof should be out over the eastern Plains by 00Z which will force
lee-side cyclogenesis back over the Colorado/Kansas border. The low
level jet ahead of the developing low level system system will
increase to 50-60kts resulting in impressive moisture transport from
the southeast. GFS and NAM both show a tremendous amount of
moisture convergence over northern Missouri/southern Iowa on the
nose of the low level jet tonight. The exact placement of the
heaviest rain is still in question with the GFS being further south
into our area, and the NAM being further north in Iowa. A deep
warm-cloud layer and P-wats over 2.3 inches will certainly provide a
rich environment for heavy rain. However, the SREF seems to agree
more with the NAM, as do the ARW and NMM WRF models. Will therefore
hold off issuing any flooding headlines and let the day shift take
another look.
Guidance is in decent agreement in pushing the surface front through
the area Wednesday afternoon. The low level jet ahead of the front
does diminish somewhat, but all models continue to show a 30-50kt
jet through much of the day with moisture convergence continuing
over the area. Think there will be ongoing precip ahead of the
front, tho areal coverage is somewhat uncertain. However, any
sunshine should allow for a rapid warm up in southwest flow and
18-20C temperatures at 850mb. Therefore stuck pretty close to MOS
highs in spite of potential for a lot of cloud cover and rain
through the day. Storms should form up into a line ahead of the
front in the afternoon and move south of the area by mid-late
evening. Still think there is a decent chance for some of the
storms to be severe given the strong winds aloft and the possibility
that downdrafts could mix these winds to the surface.
Much cooler air will filter into the area and behind the front for
Thursday. Temperatures will fall below normal, and are expected to
stay below normal through Monday. Highs through the period will
mainly be in the mid 60s to around 70 with lows as low as the low to
mid 40s. This will be 15-20 degrees below normal for
mid-September. The only significant chance for precipitation beyond
Wednesday evening looks to be on Friday when another shortwave dives
southeast out of the northern Plains across the Midwest.
Carney
&&
.AVIATION: (For the 06z TAFs through 06z Tuesday Night)
Issued at 1147 PM CDT Mon Sep 8 2014
Specifics for KUIN/KCOU: A thunderstorm complex is expected to
develop overnight and move southeastward. Thunderstorms are likely
at KUIN, but there is greater uncertainty about whether convection
would reach as far south as KCOU. Depending on where the outflow
boundaries are located, scattered thunderstorms are possible again
during the afternoon hours. LLWS conditions are expected very late
in the TAF period after a strong low level jet develops over KCOU.
Specifics for KSTL/KSUS/KCPS: A thunderstorm complex is expected
to develop overnight and move southeastward, possibly reaching the
St. Louis metro area as it dissipates. The most likely time period
for this to occur would be between 12-16z. Depending on where the
outflow boundaries are located, scattered thunderstorms are
possible during the afternoon hours. Precipitation chances
increase again very late in the TAF period at KSTL ahead of an
approaching cold front.
Kanofsky
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 87 74 87 59 / 30 60 80 50
Quincy 81 71 79 52 / 50 90 80 20
Columbia 87 71 82 55 / 30 70 80 30
Jefferson City 88 73 83 55 / 30 70 80 30
Salem 83 70 85 60 / 10 20 80 80
Farmington 86 71 87 60 / 10 30 80 70
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
320 AM CDT Tue Sep 9 2014
.SHORT TERM: (Through Late This Afternoon)
Issued at 320 AM CDT Tue Sep 9 2014
A MCS has been going on across eastern IA and northwestern IL for a
good part of the overnight and the forward flank of it is
propagating slowly east-southeast. Further south over our region,
southerly surface flow prevailed, and thanks to areas of clouds, are
keeping temps much warmer than where they were 24 hours ago, with
readings hovering near 70 in many locales.
Models not doing a very good job with handling the MCS to our north,
although the HRRR is about the most believable. The main flow and
Corfidi vectors suggest this MCS will still mainly propagate E-SE
with the main body remaining to the north of our region, but this is
kicking off an outflow and with a weak lo level jet nosing into
northeast MO, cannot rule out some sunrise surprise in the way of
widely scattered TSRA. The outflow dropping south may further
enable TSRA development into central IL heading deeper into the
morning and remain thru the afternoon, expanding westward into
northern MO.
As the heating of the day kicks in by midday, much of our region to
the west of STL will be in a weak CINH, very high moisture
environment and may be able to fire off isolated to scattered TSRA
during the afternoon. Rain chances look less likely into southern
IL, depending on how the MCS to the north actually evolves.
Due to all of the dependencies on clouds and rain chances, it will
be hard to get a firm handle on temps today. A MOS blend looks like
a reasonably good start, with above normal temps for many areas as
readings in the 80s are attained.
TES
.LONG TERM: (Tuesday through Next Monday)
Issued at 357 PM CDT Mon Sep 8 2014
Short term (Tuesday-Thursday)
Overall forecast trends remain the same for the upcoming forecast
package, with a few tweaks to PoPs in the Wednesday/Wednesday night
time frame in an attempt to fine tune surge of showers and
thunderstorms across the CWA with the cold front.
Tomorrow`s thunderstorm threat will come from a combination of
tonight`s activity lingering into the morning, and additional
development during the afternoon as the airmass destabilizes. Max
destabilization and greatest chance of redevelopment should occur in
the deeper moisture over western sections of the CWA, with models
forecasting very little if any convective inhibition during the
afternoon hours in this part of the CWA. For now have continued
with chance/scattered type PoPs over about the western half of the
area, but it may be that impacts of any outflows from the morning
convection will cause a localized increase in these PoPs. These
forecast adjustments will have to wait until overnight and Tuesday
morning convective trends become more clear.
As surface low ejects from the lee of the Rockies Tuesday night, low
level jet should strengthen dramatically across the mid-Missouri
Valley, with model consensus suggesting SW winds at 850mb of at
least 50-60kts by 06z. The resultant ascent of the very moist and
unstable airmass should produce a large area of intense convection
fueled by very moist and unstable air to the NW of our CWA during
the evening, with at least some of this activity then moving into
northern sections of the FA during the overnight hours as the low
level jet veers to the east. It is also likely that this large
complex should be preceded by some of the afternoon activity which
persists into the evening hours.
Over the weekend it appeared that convection would rumble across the
entire CWA throughout the day on Wednesday, but last several
forecast cycles seem to suggest that there may be a bit more of a
break in the precip, with morning convection moving off to the east
and waning. This will allow AMS to destabilize (temperatures
climbing into the upper 70s and 80s with dewpoints in the lower
70s), with the strong cold front then interacting with this very
unstable airmass during the afternoon to produce another round of
widespread convection along and ahead of the front. Severe weather
potential for Wednesday will definitely be tied to amount of
destabilization that can occur, with forecast soundings suggesting a
very moist AMS that would lead to damaging winds being the primary
severe weather threat.
In addition, any of the storms over the region from Tuesday
night-Wednesday evening will be very efficient rain producers, as
the tropical moisture connection pushes pwats in the warm sector
above 2 inches. Since the primary corridor for convection for
tonight-Tuesday night appears to be just north of our CWA will not
be issuing any hydro headlines, but we will be keeping an eye on
this, and will mention the threat of heavy rain in the HWO.
Models remain in good agreement with the timing of the front across
the CWA, with cold front and associated convection exiting southeast
sections of the CWA on Wednesday night. Believe effective boundary
will be far enough south on Thursday that PoPs will be south of our
CWA, so have dropped mention of showers in the far south. Leading
edge of the cold air will make Thursday a much cooler day as
compared to Wednesday, with highs dropping back into the 60s and
70s.
Medium range (Friday-Monday)
Guidance continues to suggest cool September weather heading into
the weekend and into the start of next week as upper trof digs into
and deepens over the eastern CONUS, and highs in the 60s and lows in
the 40s appear to be a good bet for Friday and Saturday. A slow
moderation should occur into early next week, but temps should still
remain below normal.
It does appear that there will be a shower threat late Thursday
night or and Friday as secondary cold front and shortwave zip across
the area; otherwise, little if any precipitation threat indicated.
Truett
&&
.AVIATION: (For the 06z TAFs through 06z Tuesday Night)
Issued at 1147 PM CDT Mon Sep 8 2014
Specifics for KUIN/KCOU: A thunderstorm complex is expected to
develop overnight and move southeastward. Thunderstorms are likely
at KUIN, but there is greater uncertainty about whether convection
would reach as far south as KCOU. Depending on where the outflow
boundaries are located, scattered thunderstorms are possible again
during the afternoon hours. LLWS conditions are expected very late
in the TAF period after a strong low level jet develops over KCOU.
Specifics for KSTL/KSUS/KCPS: A thunderstorm complex is expected
to develop overnight and move southeastward, possibly reaching the
St. Louis metro area as it dissipates. The most likely time period
for this to occur would be between 12-16z. Depending on where the
outflow boundaries are located, scattered thunderstorms are
possible during the afternoon hours. Precipitation chances
increase again very late in the TAF period at KSTL ahead of an
approaching cold front.
Kanofsky
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 87 74 87 59 / 30 60 80 50
Quincy 81 71 79 52 / 50 90 80 20
Columbia 87 71 82 55 / 30 70 80 30
Jefferson City 88 73 83 55 / 30 70 80 30
Salem 83 70 85 60 / 10 20 80 80
Farmington 86 71 87 60 / 10 30 80 70
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1216 PM CDT TUE SEP 9 2014
.UPDATE...
ISSUED AT 1215 PM CDT TUE SEP 9 2014
ELEVATED STORMS WILL CONTINUE TO LIFT ACROSS SOUTHWEST IOWA AND
PARTS OF EASTERN NEBRASKA THIS AFTERNOON...WITH SOME HAIL THREAT.
LATER...STORMS ACROSS SOUTHWEST IOWA...SOUTHEAST AND EAST CENTRAL
NEBRASKA MAY BE MORE ROOTED IN THE BOUNDARY LAYER. HAVE NOT SEEN
ANY RUNS OF THE HRRR SINCE 12Z...BUT 13KM RAP INCREASES ACTIVITY
THIS AFTERNOON AND EVENING. SURFACE LOW SHOULD BE OVER NORTH
CENTRAL IOWA BY MIDNIGHT...WITH A COLD FRONT EXTENDING DOWN OVER
SOUTHEAST NEBRASKA AT THAT TIME.
&&
UPDATE ISSUED AT 925 AM CDT TUE SEP 9 2014
LET DENSE FOG ADVISORY EXPIRE AS SCHEDULED. EXPECT STORMS TO INCREASE
IN COVERAGE THE NEXT 6 HOURS.
&&
.UPDATE...
ISSUED AT 618 AM CDT TUE SEP 9 2014
A DENSE FOG ADVISORY WAS ISSUED EARLIER FOR PORTIONS OF NORTHEAST
NEBRASKA WHERE VISIBILITIES HAD DROPPED TO ONE QUARTER MILE.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 300 AM CDT TUE SEP 9 2014
TIMING OF COLD FRONT AND EXTENT OF PRECIP WILL BE THE MAIN CONCERN
IN THE SHORT TERM.
PRECIP RATHER SPARSE ACROSS THE REGION AT THIS TIME DUE TO
LIMITED FORCING. A COLD FRONT WAS LOCATED ACROSS NORTHERN SOUTH
DAKOTA AT 07Z AND A WARM FRONT FROM CENTRAL IOWA ACROSS NORTHWEST
KANSAS TO LOW PRESSURE OVER EASTERN COLORADO. LATEST RAP AND HRRR
INDICATE SHOWERS AND ISOLATED THUNDER TO DEVELOP OR MOVE INTO
CENTRAL NEBRASKA BY 12Z AND INCREASE IN COVERAGE THROUGH 18Z AS
MID LEVEL WAVE APPROACHES THE HIGH PLAINS AND 850MB FLOW INCREASES
AS SURFACE LOW DEEPENS OVER EASTERN COLORADO. FORCING CONTINUES TO
INCREASE AFTER 18Z AND INTO THE EVENING AS THE SYSTEM INTENSIFIES
WITH HIGHER POPS SPREADING INTO THE CWA AS COLD FRONT APPROACHES
AND MOVES INTO EASTERN NEBRASKA. MAJORITY OF THE CONVECTION SHOULD
BE EAST OF THE AREA BY 06Z BUT SHOWERS OR LIGHT RAIN WILL LIKELY
CONTINUE INTO WEDNESDAY MORNING AS UPPER WAVE TRACKS ACROSS THE
CENTRAL PLAINS.
COLDER AIR FOLLOWS BEHIND THE FRONT WEDNESDAY INTO THURSDAY WITH
POTENTIAL FOR SOME RECORD LOWEST MAXIMUM TEMPERATURES.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 300 AM CDT TUE SEP 9 2014
COLD TEMPERATURES LINGER THROUGH FRIDAY WITH WARMER AIR COMING
BACK INTO THE AREA FOR THE WEEKEND. ANOTHER ROUND OF RAIN LIKELY
THURSDAY NIGHT INTO FRIDAY MORNING FORCING ASSOCIATED WITH ANOTHER
STRONG UPPER WAVE MOVES ACROSS THE AREA.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1215 PM CDT TUE SEP 9 2014
LOOK FOR DETERIORATING CONDITIONS TO MVFR OR LOWER WITH TSTMS THEN
TRENDING TOWARD IFR AFTER WINDS TURN TO THE NORTH. DID KEEP SOME
WIND GUSTS IN TAFS AND MAY ADD HAIL IF THINGS TREND THAT WAY.
CONDITIONS WILL SLOWLY IMPROVE TO MVFR BY EARLY AFTN WED.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
UPDATE...MILLER
SHORT TERM...FOBERT
LONG TERM...FOBERT
AVIATION...MILLER
AREA FORECAST DISCUSSION...UPDATED
NWS OMAHA/VALLEY NE
923 AM CDT TUE SEP 9 2014
.UPDATE...
ISSUED AT 925 AM CDT TUE SEP 9 2014
LET DENSE FOG ADVISORY EXPIRE AS SCHEDULED. EXPECT STORMS TO INCREASE
IN COVERAGE THE NEXT 6 HOURS.
.UPDATE...
ISSUED AT 618 AM CDT TUE SEP 9 2014
A DENSE FOG ADVISORY WAS ISSUED EARLIER FOR PORTIONS OF NORTHEAST
NEBRASKA WHERE VISIBILITIES HAD DROPPED TO ONE QUARTER MILE.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 300 AM CDT TUE SEP 9 2014
TIMING OF COLD FRONT AND EXTENT OF PRECIP WILL BE THE MAIN CONCERN
IN THE SHORT TERM.
PRECIP RATHER SPARSE ACROSS THE REGION AT THIS TIME DUE TO
LIMITED FORCING. A COLD FRONT WAS LOCATED ACROSS NORTHERN SOUTH
DAKOTA AT 07Z AND A WARM FRONT FROM CENTRAL IOWA ACROSS NORTHWEST
KANSAS TO LOW PRESSURE OVER EASTERN COLORADO. LATEST RAP AND HRRR
INDICATE SHOWERS AND ISOLATED THUNDER TO DEVELOP OR MOVE INTO
CENTRAL NEBRASKA BY 12Z AND INCREASE IN COVERAGE THROUGH 18Z AS
MID LEVEL WAVE APPROACHES THE HIGH PLAINS AND 850MB FLOW INCREASES
AS SURFACE LOW DEEPENS OVER EASTERN COLORADO. FORCING CONTINUES TO
INCREASE AFTER 18Z AND INTO THE EVENING AS THE SYSTEM INTENSIFIES
WITH HIGHER POPS SPREADING INTO THE CWA AS COLD FRONT APPROACHES
AND MOVES INTO EASTERN NEBRASKA. MAJORITY OF THE CONVECTION SHOULD
BE EAST OF THE AREA BY 06Z BUT SHOWERS OR LIGHT RAIN WILL LIKELY
CONTINUE INTO WEDNESDAY MORNING AS UPPER WAVE TRACKS ACROSS THE
CENTRAL PLAINS.
COLDER AIR FOLLOWS BEHIND THE FRONT WEDNESDAY INTO THURSDAY WITH
POTENTIAL FOR SOME RECORD LOWEST MAXIMUM TEMPERATURES.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 300 AM CDT TUE SEP 9 2014
COLD TEMPERATURES LINGER THROUGH FRIDAY WITH WARMER AIR COMING
BACK INTO THE AREA FOR THE WEEKEND. ANOTHER ROUND OF RAIN LIKELY
THURSDAY NIGHT INTO FRIDAY MORNING FORCING ASSOCIATED WITH ANOTHER
STRONG UPPER WAVE MOVES ACROSS THE AREA.
&&
.AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 618 AM CDT TUE SEP 9 2014
VERY BUSY AVIATION FORECAST TODAY WITH NUMEROUS CHALLENGES. DENSE
FOG WITH LIFR CONDITIONS HAD DEVELOPED AT KOFK...WHICH WILL
PERSIST UNTIL ABOUT 14-15Z. OTHERWISE...THUNDERSTORMS ARE EXPECTED
TO DEVELOP AT ALL TAF SITES LATER TODAY...BEGINNING BY 20Z AT
KLNK...22Z AND KOMA AND 23Z AT KOFK. STORMS COULD BE QUITE STRONG
WITH VARIABLE WINDS UP TO 30 TO 45 KNOTS. A COLD FRONT THEN SWEEPS
INTO THE REGION 03-06Z...WHICH BRINGS WINDS AROUND TO THE NORTH
NORTHWEST...WITH LIFR/IFR CONDITIONS DEVELOPING BEHIND THE FRONT.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
UPDATE...MILLER
SHORT TERM...FOBERT
LONG TERM...FOBERT
AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
621 AM CDT TUE SEP 9 2014
.UPDATE...
ISSUED AT 618 AM CDT TUE SEP 9 2014
A DENSE FOG ADVISORY WAS ISSUED EARLIER FOR PORTIONS OF NORTHEAST
NEBRASKA WHERE VISIBILITIES HAD DROPPED TO ONE QUARTER MILE.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 300 AM CDT TUE SEP 9 2014
TIMING OF COLD FRONT AND EXTENT OF PRECIP WILL BE THE MAIN CONCERN
IN THE SHORT TERM.
PRECIP RATHER SPARSE ACROSS THE REGION AT THIS TIME DUE TO
LIMITED FORCING. A COLD FRONT WAS LOCATED ACROSS NORTHERN SOUTH
DAKOTA AT 07Z AND A WARM FRONT FROM CENTRAL IOWA ACROSS NORTHWEST
KANSAS TO LOW PRESSURE OVER EASTERN COLORADO. LATEST RAP AND HRRR
INDICATE SHOWERS AND ISOLATED THUNDER TO DEVELOP OR MOVE INTO
CENTRAL NEBRASKA BY 12Z AND INCREASE IN COVERAGE THROUGH 18Z AS
MID LEVEL WAVE APPROACHES THE HIGH PLAINS AND 850MB FLOW INCREASES
AS SURFACE LOW DEEPENS OVER EASTERN COLORADO. FORCING CONTINUES TO
INCREASE AFTER 18Z AND INTO THE EVENING AS THE SYSTEM INTENSIFIES
WITH HIGHER POPS SPREADING INTO THE CWA AS COLD FRONT APPROACHES
AND MOVES INTO EASTERN NEBRASKA. MAJORITY OF THE CONVECTION SHOULD
BE EAST OF THE AREA BY 06Z BUT SHOWERS OR LIGHT RAIN WILL LIKELY
CONTINUE INTO WEDNESDAY MORNING AS UPPER WAVE TRACKS ACROSS THE
CENTRAL PLAINS.
COLDER AIR FOLLOWS BEHIND THE FRONT WEDNESDAY INTO THURSDAY WITH
POTENTIAL FOR SOME RECORD LOWEST MAXIMUM TEMPERATURES.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 300 AM CDT TUE SEP 9 2014
COLD TEMPERATURES LINGER THROUGH FRIDAY WITH WARMER AIR COMING
BACK INTO THE AREA FOR THE WEEKEND. ANOTHER ROUND OF RAIN LIKELY
THURSDAY NIGHT INTO FRIDAY MORNING FORCING ASSOCIATED WITH ANOTHER
STRONG UPPER WAVE MOVES ACROSS THE AREA.
&&
.AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 618 AM CDT TUE SEP 9 2014
VERY BUSY AVIATION FORECAST TODAY WITH NUMEROUS CHALLENGES. DENSE
FOG WITH LIFR CONDITIONS HAD DEVELOPED AT KOFK...WHICH WILL
PERSIST UNTIL ABOUT 14-15Z. OTHERWISE...THUNDERSTORMS ARE EXPECTED
TO DEVELOP AT ALL TAF SITES LATER TODAY...BEGINNING BY 20Z AT
KLNK...22Z AND KOMA AND 23Z AT KOFK. STORMS COULD BE QUITE STRONG
WITH VARIABLE WINDS UP TO 30 TO 45 KNOTS. A COLD FRONT THEN SWEEPS
INTO THE REGION 03-06Z...WHICH BRINGS WINDS AROUND TO THE NORTH
NORTHWEST...WITH LIFR/IFR CONDITIONS DEVELOPING BEHIND THE FRONT.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR NEZ011-012-
015>018-030>033-042-043.
IA...NONE.
&&
$$
UPDATE...DEWALD
SHORT TERM...FOBERT
LONG TERM...FOBERT
AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
259 AM CDT TUE SEP 9 2014
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 300 AM CDT TUE SEP 9 2014
TIMING OF COLD FRONT AND EXTENT OF PRECIP WILL BE THE MAIN CONCERN
IN THE SHORT TERM.
PRECIP RATHER SPARCE ACROSS THE REGION AT THIS TIME DUE TO
LIMITED FORCING. A COLD FRONT WAS LOCATED ACROSS NORTHERN SOUTH
DAKOTA AT 07Z AND A WARM FRONT FROM CENTRAL IOWA ACROSS NORTHWEST
KANSAS TO LOW PRESSURE OVER EASTERN COLORADO. LATEST RAP AND HRRR
INDICATE SHOWERS AND ISOLATED THUNDER TO DEVELOP OR MOVE INTO
CENTRAL NEBRASKA BY 12Z AND INCREASE IN COVERAGE THROUGH 18Z AS
MID LEVEL WAVE APPROACHES THE HIGH PLAINS AND 850MB FLOW INCREASES
AS SURFACE LOW DEEPENS OVER EASTERN COLORADO. FORCING CONTINUES TO
INCREASE AFTER 18Z AND INTO THE EVENING AS THE SYSTEM INTENSIFIES
WITH HIGHER POPS SPREADING INTO THE CWA AS COLD FRONT APPROACHES
AND MOVES INTO EASTERN NEBRASKA. MAJORITY OF THE CONVECTION SHOULD
BE EAST OF THE AREA BY 06Z BUT SHOWERS OR LIGHT RAIN WILL LIKELY
CONTINUE INTO WEDNESDAY MORNING AS UPPER WAVE TRACKS ACROSS THE
CENTRAL PLAINS.
COLDER AIR FOLLOWS BEHIND THE FRONT WEDNESDAY INTO THURSDAY WITH
POTENTIAL FOR SOME RECORD LOWEST MAXIMUM TEMPERATURES.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 300 AM CDT TUE SEP 9 2014
COLD TEMPERATURES LINGER THROUGH FRIDAY WITH WARMER AIR COMING
BACK INTO THE AREA FOR THE WEEKEND. ANOTHER ROUND OF RAIN LIKELY
THURSDAY NIGHT INTO FRIDAY MORNING FORCING ASSOCIATED WITH ANOTHER
STRONG UPPER WAVE MOVES ACROSS THE AREA.
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 631 PM CDT MON SEP 8 2014
MAIN AVN CONCERN IS POSSIBLE SVR TSRA DEVELOPING OVER ERN NEB TUES
AFTN. AN AREA OF SFC LOW PRESSURE IS EXPECTED TO ORGANIZE OVER THE
CNTRL HIGH PLAINS LATER TONIGHT THEN RAPIDLY DEEPEN THRU THE DAY ON
TUES. MAIN FOCUS THEN TUES AFTN WILL BE UPON ASSOCIATED WARM
FRONT LIFTING THRU THE REGION WITH TSRA ACTIVITY LIKELY. WITH HIGH
DEGREE OF ENVIRONMENTAL SHEAR IN PLACE...SVR TSRA DEVELOPMENT IS
QUITE PROBABLE AND WILL BE A THREAT TO ALL TERMINALS. IN
ADDITION...A FEW TORNADIC STORMS CANNOT BE RULED OUT.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...FOBERT
LONG TERM...FOBERT
AVIATION...DEE
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1232 PM EDT TUE SEP 9 2014
.SYNOPSIS...
A LINGERING FRONT ALONG THE COAST WILL FINALLY PUSH WELL SOUTH AND
EAST OF THE AREA TONIGHT. DRIER AIR WILL ARRIVE TONIGHT...WITH DRY
AND WARM CONDITIONS WEDNESDAY AND THURSDAY. A COLD FRONT WILL ARRIVE
LATE WEEK...DRIFTING SOUTH EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 PM TUESDAY...TEMPERATURES ARE RUNNING A COUPLE OF DEGREES
BEHIND SCHEDULE. WITH SATELLITE IMAGERY SHOWING A FAIRLY SOLID
OVERCAST I HAVE TRIMMED BACK FORECAST HIGHS BY A COUPLE OF DEGREES
IN MOST AREAS...WITH UPPER 70S EXPECTED EVERYWHERE EXCEPT FOR THE SC
PEE DEE REGION WHERE 80-82 MAY STILL OCCUR LATE IN THE DAY. NO OTHER
SIGNIFICANT CHANGES WERE MADE. PREVIOUS DISCUSSION FROM 1000 AM
FOLLOWS...
LOW PRESSURE HAS JUST MOVED OFF THE NORTHERNMOST OUTER BANKS WITH A
COLD FRONT EXTENDING SOUTHWARD TO JUST OFF OUR PORTION OF THE COAST.
WINDS AT THE BEACHES ARE WEST TO NORTHWEST AND VEER AROUND THE NORTH
ALONG THE INTERSTATE 95 CORRIDOR. SATELLITE SHOWS PLENTY OF LOW
CLOUDS BLANKETING ALL OF THE CAROLINAS...AND HOW THE BEHAVIOR OF
THESE CLOUDS WILL DETERMINE VIRTUALLY EVERY FORECAST PARAMETER IN
TODAY`S FORECAST.
12Z SOUNDINGS FROM MHX AND GSO WERE NOT TOO DISSIMILAR FROM 06Z
MODEL SOUNDINGS VALID AT 12Z. AT GREENSBORO CLOUDS EXTENDED UP TO
AROUND 3500 FT WITH SUBSTANTIAL DRYING BEGINNING AT 6200 FT. THIS
DRYING ALOFT IS EVEN DISCERNIBLE ON WATER VAPOR IMAGERY. AT MHX THE
ENTIRE SOUNDING WAS MUCH MORE MOIST WITH PRECIPITABLE WATER STILL
OVER 2 INCHES. SINCE THERE WILL BE NO SUBSTANTIAL ADVECTION OF DRY
AIR WITHIN THE BOUNDARY LAYER TODAY ANY HEATING/DESTABILIZATION OF
THE BOUNDARY LAYER WILL PROBABLY JUST CREATE CUMULUS CLOUDS THAT
WILL FILL IN ANY HOLES THAT LET THE SUN THROUGH IN THE FIRST PLACE.
FOR THIS REASON MY SKY COVER FORECAST IS FOR CLOUDY TO MOSTLY CLOUDY
CONDITIONS THROUGH THE DAY.
HIGH TEMPERATURES SHOULD RANGE AROUND 80 ACROSS SE NORTH CAROLINA TO
THE LOWER 80S FROM DILLON...CONWAY TO MYRTLE BEACH. FARTHER INLAND
ACROSS THE PEE DEE REGION IT REMAINS POSSIBLE HIGHS COULD REACH
83-84 BUT THAT`S GOING TO TAKE SEVERAL HOURS OF THIN SPOTS IN THE
CLOUD COVER TO ACHIEVE.
PRECIPITATION CHANCES APPEAR QUITE LOW THROUGH THE DAY. RADAR SHOWS
NO CURRENT ACTIVITY ON LAND AND THE AMOUNT OF HEATING EXPECTED THIS
AFTERNOON SHOULD NOT BE ABLE TO PUT CONVECTIVE CLOUDS UP THROUGH A
CONVECTIVE CAP BETWEEN 6000-9000 FEET. THE HRRR MAY HAVE THE RIGHT
IDEA WITH JUST A FEW SPRINKLES FALLING FROM TOWERING CUMULUS THIS
AFTERNOON.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 AM TUESDAY...ZONAL MID LEVEL FLOW AND A DISSIPATING
SURFACE HIGH ON WEDNESDAY WILL BRING A DRY DAY WITH NEAR SEASONABLE
TEMPERATURES. ON THURSDAY THE APPROACH OF A COLD FRONT AND A SLIGHT
STRENGTHENING OF THE WEST ATLANTIC HIGH WILL BOOST THE AFTERNOON
WARMTH AS WELL SLIGHTLY MOISTEN THE LOW LEVELS OF THE ATMOSPHERE.
MOST PLACES AWAY FROM THE IMMEDIATE COASTLINE SHOULD WARM INTO THE
LOW 90S. THE MORE NOTICEABLE DIFFERENCE BETWEEN THE TWO DAYS WILL BE
THE AFTERNOON APPARENT TEMPERATURES.ON WEDNESDAY MOST PLACES WILL
TOP OUT AROUND 90 DEGREES BUT AS THE DEWPOINTS RISE THURSDAY THE
HEAT INDICES WILL BE IN THE UPPER 90S. BOTH DAYS THIS EFFECT WILL BE
CONSIDERABLY TAPERED ALONG THE COAST. MODELS TRENDING A BIT FASTER
WITH MOISTURE RETURN AHEAD OF NEXT COLD FRONT ESP THE GFS. WILL PUT
LOW POPS IN TOWARDS THE END OF THE PERIOD.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 300 AM TUESDAY...COLD FRONT ENTERS THE AREA ON FRIDAY AND MAY
TAKE A FULL 24 HOURS TO THEN BE ORIENTED RIGHT ALONG THE COAST LINE.
THIS SHOULD KEEP THINGS QUITE UNSETTLED FRIDAY AND PROBABLY SATURDAY
AS WELL. MODELS CANNOT SEEM TO DECIDE WHERE THE CORE OF THE COOL AIR
GOES HOWEVER. NORMALLY IN EARLY SEPTEMBER THIS ISN`T TOO BIG A DEAL
AS COOL FRONTS USUALLY JUST REPRESENT A DROP IN HUMIDITY THIS FAR
SOUTH. HOWEVER THIS COLD FRONT WILL HAVE SOME CONSIDERABLY COOLER
AND DRIER AIR AND THE GFS IN PARTICULAR IS NOW HESITANT TO SHOVE IT
THIS FAR SOUTH. INSTEAD THE MODEL KEEPS THE SECONDARY FRONT...THE
MUCH COOLER AIR...OFF TO OUR NORTH AND WEST WHILE THE LEADING AND
MUCH WEAKER FRONT MEANDERS AND WEAKENS NEAR THE COAST FOR THE REST
OF THE PERIOD. THE ADDED CLOUD COVER THAT THE FRONT WOULD YIELD
WOULD KEEP TEMPS DOWN AND THERE WILL STILL BE AN AIRMASS CHANGE FROM
THE SHORT TERM PERIOD TO BE SURE...BUT I`M NO LONGER CERTAIN WE`RE
IN FOR A `REFRESHING` AIRMASS THAT WE NORMALLY EXPERIENCE MUCH LATER
IN THE MONTH OR EVEN OCTOBER. A GLANCE AT THE NEW 00Z ECMWF WOULD
IMPLY THAT THE LATE PERIOD COOL DOWN WHILE STILL PRESENT...MAY NOT
BE VERY NOTEWORTHY.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 18Z...WIDESPREAD MVFR CIGS ARE OCCURRING ACROSS THE TERMINALS
THIS AFTERNOON. CIGS HAVE BEEN VERY SLOW TO RISE. LATEST FORECAST
SOUNDINGS SUGGEST THAT ALTHOUGH CIGS WILL CONTINUE TO SLOWLY
RISE...IMPROVEMENT TO VFR WILL NOT OCCUR AT KFLO UNTIL 19-21Z...AND
KLBT 22-00Z. MVFR CIGS MAY IMPROVE TO VFR FOR AWHILE THIS EVENING AT
THE COASTAL TERMINALS...BUT MVFR CIGS POTENTIALLY COULD CONTINUE
THROUGH THE OVERNIGHT HOURS. WINDS WILL BE NW-N AT KFLO/KLBT THIS
AFTERNOON. AT THE COASTAL TERMINALS WINDS WILL BE W-NW...EXCEPT
BECOMING SW AT KCRE/KMYR LATER THIS AFTERNOON. WINDS BECOME
LIGHT/VRBL THIS EVENING ALL TERMINALS.
THERE IS MODERATE CONFIDENCE FOG WILL DEVELOP OVERNIGHT...BUT
POTENTIAL LOW CLOUD COVER WILL LIMIT INSOLATION. EXPECT EITHER MVFR
CIGS AND/OR VSBYS OVERNIGHT AT THE COASTAL TERMINALS WHERE CLOUD
COVER IS POTENTIALLY THE GREATEST. IFR OR LOWER VSBYS ARE MORE
LIKELY OCCUR AT KFLO/KLBT...WITH HIGHEST CONFIDENCE LIFR AT KFLO.
ANY SUB-VFR CONDITIONS AT THE TERMINALS IMPROVE TO VFR AROUND
13Z...ALTHOUGH TEMPO MVFR CIGS WILL REMAIN POSSIBLE AT THE COASTAL
TERMINALS THROUGH LATE MORNING. LIGHT NE WINDS EXPECTED EARLY
BECOMING LGT/VRBL.
EXTENDED OUTLOOK...VFR WILL PREVAIL WEDNESDAY AND THURSDAY. SHOWERS
AND TSTMS RETURN FRIDAY AND SATURDAY AS ANOTHER COLD FRONT NEARS THE
CAROLINAS. SHOWERS WITH MVFR/IFR POSSIBLE SUNDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 PM TUESDAY...MAINLY DUE TO MORE CLOUD COVER INLAND I HAVE
REMOVED THE POTENTIAL FOR AN AFTERNOON SEABREEZE FROM THE WIND
FORECASTS. NORTHWESTERLY WINDS ARE NOW EXPECTED TO CONTINUE
THROUGHOUT THE DAY...STRONGEST NORTH OF CAPE FEAR WHERE BEACH
OBSERVATIONS AND OFFSHORE BUOYS ARE STILL SHOWING GUSTS AS HIGH AS
17 KNOTS WITHIN THE PAST HOUR. NO OTHER SIGNIFICANT CHANGES.
PREVIOUS DISCUSSION FROM 1000 AM FOLLOWS...
THE COLD FRONT HAS PUSHED OUT ACROSS THE COASTAL WATERS WITH WEST TO
NORTHWEST WINDS CURRENTLY OBSERVED ALONG THE BEACHES. WIND SPEEDS
ARE HIGHEST NORTH OF CAPE FEAR (UP TO 15 KNOTS) BUT ARE GENERALLY 10
KNOTS OR LESS SOUTH OF CAPE FEAR. LOW PRESSURE IS JUST EAST OF THE
NORTHERNMOST OUTER BANKS AND SHOULD CONTINUE TO PUSH NORTHEASTWARD
AND AWAY FROM THE AREA TODAY. RADAR SHOWS ONLY SOME SPRINKLES SOUTH
OF GEORGETOWN WITH HEAVIER SHOWERS CONFINED TO THE OFFSHORE WATERS
40 MILES AND FARTHER OFFSHORE.
FOR THE REST OF THE DAY THE FRONT SHOULD STALL ACROSS THE OFFSHORE
WATERS WITH LIGHT GENERALLY NORTHWEST WINDS EXPECTED. WHERE INLAND
AIR TEMPERATURES CAN REACH THE LOWER 80S OR BETTER (MAINLY SOUTH
CAROLINA) NEARSHORE WIND DIRECTIONS MAY BACK MORE SOUTHWESTERLY OR
SOUTHERLY WITH A VERY WEAK SEABREEZE FOR A FEW HOURS DURING THE LATE
AFTERNOON.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 AM TUESDAY...WIND AND SEAS BOTH MINIMAL ON WEDNESDAY. HIGH
PRESSURE INITIALLY OVER THE LANDMASS WEDNESDAY WASHES OUT AS THE DAY
WEARS ON. NE FLOW TO START THE DAY WILL GIVE TO WAY LIGHT AND
SOMEWHAT VARIABLE FLOW POSSIBLY EVEN DOMINATED BY MESOSCALE SEA
BREEZE AT LEAST NEAR THE SHORELINE. SOUTHWESTERLY FLOW BECOMES
ESTABLISHED ON THURSDAY AS A COLD FRONT APPROACHES FROM THE
NORTHWEST AND THE WEST ATLANTIC HIGH ALSO STRENGTHENS SOMEWHAT. NOT
LOOKING FOR SEAS TO INCREASE AS A RESULT OF THE NEW FLOW REGIME ON
ACCOUNT OF HOW WEAK WIND SPEEDS STAY PLUS THE FACT THAT NO
SIGNIFICANT SWELL ENERGY FOUND ANYWHERE OVER THE WEST ATLANTIC.
LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 300 AM TUESDAY...A COLD FRONT WILL APPROACH FROM THE WEST ON
FRIDAY ALBEIT VERY SLOWLY. THERE WILL BE VERY LITTLE GRADIENT FLOW
AHEAD OF THE BOUNDARY AND NOT MUCH BEHIND IT EITHER. IT WILL STALL
RIGHT ALONG THE COASTLINE EARLY SATURDAY AND MAY EVEN DRIFT A BIT
INLAND AS THE DAY WEARS ON. THIS KEEPS A SOUTHERLY COMPONENT TO THE
FLOW THROUGH THE ENTIRE PERIOD WITH SPEEDS HARD-PRESSED TO EXCEED 10
KT. THERE MAY BE VACILLATIONS IN DIRECTION OF THE SRLY FLOW FROM SE
TO SW AT TIMES ESPECIALLY ALONG THE COAST WITH SEA BREEZE
CIRCULATIONS. WITH SUCH LIGHT WINDS AND NO SWELL ENERGY TO SPEAK OF
SEAS WILL REMAIN MINIMAL, CAPPED AT 2 FT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...COASTAL FLOOD ADVISORY UNTIL NOON EDT TODAY FOR NCZ107.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...MRR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1012 AM EDT TUE SEP 9 2014
.SYNOPSIS...
A LINGERING FRONT ALONG THE COAST WILL FINALLY PUSH WELL SOUTH AND
EAST OF THE AREA TONIGHT. DRIER AIR WILL ARRIVE TONIGHT...WITH DRY
AND WARM CONDITIONS WEDNESDAY AND THURSDAY. A COLD FRONT WILL ARRIVE
LATE WEEK...DRIFTING SOUTH EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM TUESDAY...LOW PRESSURE HAS JUST MOVED OFF THE
NORTHERNMOST OUTER BANKS WITH A COLD FRONT EXTENDING SOUTHWARD TO
JUST OFF OUR PORTION OF THE COAST. WINDS AT THE BEACHES ARE WEST TO
NORTHWEST AND VEER AROUND THE NORTH ALONG THE INTERSTATE 95
CORRIDOR. SATELLITE SHOWS PLENTY OF LOW CLOUDS BLANKETING ALL OF THE
CAROLINAS...AND HOW THE BEHAVIOR OF THESE CLOUDS WILL DETERMINE
VIRTUALLY EVERY FORECAST PARAMETER IN TODAY`S FORECAST.
12Z SOUNDINGS FROM MHX AND GSO WERE NOT TOO DISSIMILAR FROM 06Z
MODEL SOUNDINGS VALID AT 12Z. AT GREENSBORO CLOUDS EXTENDED UP TO
AROUND 3500 FT WITH SUBSTANTIAL DRYING BEGINNING AT 6200 FT. THIS
DRYING ALOFT IS EVEN DISCERNIBLE ON WATER VAPOR IMAGERY. AT MHX THE
ENTIRE SOUNDING WAS MUCH MORE MOIST WITH PRECIPITABLE WATER STILL
OVER 2 INCHES. SINCE THERE WILL BE NO SUBSTANTIAL ADVECTION OF DRY
AIR WITHIN THE BOUNDARY LAYER TODAY ANY HEATING/DESTABILIZATION OF
THE BOUNDARY LAYER WILL PROBABLY JUST CREATE CUMULUS CLOUDS THAT
WILL FILL IN ANY HOLES THAT LET THE SUN THROUGH IN THE FIRST PLACE.
FOR THIS REASON MY SKY COVER FORECAST IS FOR CLOUDY TO MOSTLY CLOUDY
CONDITIONS THROUGH THE DAY.
HIGH TEMPERATURES SHOULD RANGE AROUND 80 ACROSS SE NORTH CAROLINA TO
THE LOWER 80S FROM DILLON...CONWAY TO MYRTLE BEACH. FARTHER INLAND
ACROSS THE PEE DEE REGION IT REMAINS POSSIBLE HIGHS COULD REACH
83-84 BUT THAT`S GOING TO TAKE SEVERAL HOURS OF THIN SPOTS IN THE
CLOUD COVER TO ACHIEVE.
PRECIPITATION CHANCES APPEAR QUITE LOW THROUGH THE DAY. RADAR SHOWS
NO CURRENT ACTIVITY ON LAND AND THE AMOUNT OF HEATING EXPECTED THIS
AFTERNOON SHOULD NOT BE ABLE TO PUT CONVECTIVE CLOUDS UP THROUGH A
CONVECTIVE CAP BETWEEN 6000-9000 FEET. THE HRRR MAY HAVE THE RIGHT
IDEA WITH JUST A FEW SPRINKLES FALLING FROM TOWERING CUMULUS THIS
AFTERNOON.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 AM TUESDAY...ZONAL MID LEVEL FLOW AND A DISSIPATING
SURFACE HIGH ON WEDNESDAY WILL BRING A DRY DAY WITH NEAR SEASONABLE
TEMPERATURES. ON THURSDAY THE APPROACH OF A COLD FRONT AND A SLIGHT
STRENGTHENING OF THE WEST ATLANTIC HIGH WILL BOOST THE AFTERNOON
WARMTH AS WELL SLIGHTLY MOISTEN THE LOW LEVELS OF THE ATMOSPHERE.
MOST PLACES AWAY FROM THE IMMEDIATE COASTLINE SHOULD WARM INTO THE
LOW 90S. THE MORE NOTICEABLE DIFFERENCE BETWEEN THE TWO DAYS WILL BE
THE AFTERNOON APPARENT TEMPERATURES.ON WEDNESDAY MOST PLACES WILL
TOP OUT AROUND 90 DEGREES BUT AS THE DEWPOINTS RISE THURSDAY THE
HEAT INDICES WILL BE IN THE UPPER 90S. BOTH DAYS THIS EFFECT WILL BE
CONSIDERABLY TAPERED ALONG THE COAST. MODELS TRENDING A BIT FASTER
WITH MOISTURE RETURN AHEAD OF NEXT COLD FRONT ESP THE GFS. WILL PUT
LOW POPS IN TOWARDS THE END OF THE PERIOD.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 300 AM TUESDAY...COLD FRONT ENTERS THE AREA ON FRIDAY AND MAY
TAKE A FULL 24 HOURS TO THEN BE ORIENTED RIGHT ALONG THE COAST LINE.
THIS SHOULD KEEP THINGS QUITE UNSETTLED FRIDAY AND PROBABLY SATURDAY
AS WELL. MODELS CANNOT SEEM TO DECIDE WHERE THE CORE OF THE COOL AIR
GOES HOWEVER. NORMALLY IN EARLY SEPTEMBER THIS ISN`T TOO BIG A DEAL
AS COOL FRONTS USUALLY JUST REPRESENT A DROP IN HUMIDITY THIS FAR
SOUTH. HOWEVER THIS COLD FRONT WILL HAVE SOME CONSIDERABLY COOLER
AND DRIER AIR AND THE GFS IN PARTICULAR IS NOW HESITANT TO SHOVE IT
THIS FAR SOUTH. INSTEAD THE MODEL KEEPS THE SECONDARY FRONT...THE
MUCH COOLER AIR...OFF TO OUR NORTH AND WEST WHILE THE LEADING AND
MUCH WEAKER FRONT MEANDERS AND WEAKENS NEAR THE COAST FOR THE REST
OF THE PERIOD. THE ADDED CLOUD COVER THAT THE FRONT WOULD YIELD
WOULD KEEP TEMPS DOWN AND THERE WILL STILL BE AN AIRMASS CHANGE FROM
THE SHORT TERM PERIOD TO BE SURE...BUT I`M NO LONGER CERTAIN WE`RE
IN FOR A `REFRESHING` AIRMASS THAT WE NORMALLY EXPERIENCE MUCH LATER
IN THE MONTH OR EVEN OCTOBER. A GLANCE AT THE NEW 00Z ECMWF WOULD
IMPLY THAT THE LATE PERIOD COOL DOWN WHILE STILL PRESENT...MAY NOT
BE VERY NOTEWORTHY.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
AS OF 12Z...THERE IS HIGH CONFIDENCE FLIGHT CONDITIONS WILL IMPROVE
TO VFR TODAY. LIGHT SPRINKLES ARE POSSIBLE THIS MORNING...BUT IN
GENERAL RAINFALL CHANCES WILL DECREASE AS THE DAY PROGRESSES.
ALTHOUGH TEMPO CIG IMPROVEMENTS TO MVFR MAY OCCUR EARLIER...CIGS
WILL IMPROVE TO MVFR 14-16Z WITH VFR DEVELOPING THIS AFTERNOON.
WINDS WILL BE W-NW...EXCEPT BECOMING S-SW AT THE COASTAL TERMINALS
THIS AFTERNOON. WINDS WILL BECOME LIGHT/VRBL THIS EVENING AS SKIES
SCT. WITH SATURATED SOILS FOG APPEARS LIKELY WITH MVFR VSBYS
DEVELOPING BY 08Z ALL TERMINALS. LIFR APPEARS LIKELY AT KFLO/KLBT
BY 09Z. COASTAL TERMINALS WILL HAVE TEMPO LIFR CIGS IFR VSBYS DUE
TO A LIGHT N WIND.
EXTENDED OUTLOOK...VFR WILL PREVAIL WEDNESDAY AND THURSDAY. SHOWERS
AND TSTMS RETURN FRIDAY AND SATURDAY AS ANOTHER COLD FRONT NEARS THE
CAROLINAS.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM TUESDAY...THE COLD FRONT HAS PUSHED OUT ACROSS THE
COASTAL WATERS WITH WEST TO NORTHWEST WINDS CURRENTLY OBSERVED ALONG
THE BEACHES. WIND SPEEDS ARE HIGHEST NORTH OF CAPE FEAR (UP TO 15
KNOTS) BUT ARE GENERALLY 10 KNOTS OR LESS SOUTH OF CAPE FEAR. LOW
PRESSURE IS JUST EAST OF THE NORTHERNMOST OUTER BANKS AND SHOULD
CONTINUE TO PUSH NORTHEASTWARD AND AWAY FROM THE AREA TODAY. RADAR
SHOWS ONLY SOME SPRINKLES SOUTH OF GEORGETOWN WITH HEAVIER SHOWERS
CONFINED TO THE OFFSHORE WATERS 40 MILES AND FARTHER OFFSHORE.
FOR THE REST OF THE DAY THE FRONT SHOULD STALL ACROSS THE OFFSHORE
WATERS WITH LIGHT GENERALLY NORTHWEST WINDS EXPECTED. WHERE INLAND
AIR TEMPERATURES CAN REACH THE LOWER 80S OR BETTER (MAINLY SOUTH
CAROLINA) NEARSHORE WIND DIRECTIONS MAY BACK MORE SOUTHWESTERLY OR
SOUTHERLY WITH A VERY WEAK SEABREEZE FOR A FEW HOURS DURING THE LATE
AFTERNOON.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 AM TUESDAY...WIND AND SEAS BOTH MINIMAL ON WEDNESDAY. HIGH
PRESSURE INITIALLY OVER THE LANDMASS WEDNESDAY WASHES OUT AS THE DAY
WEARS ON. NE FLOW TO START THE DAY WILL GIVE TO WAY LIGHT AND
SOMEWHAT VARIABLE FLOW POSSIBLY EVEN DOMINATED BY MESOSCALE SEA
BREEZE AT LEAST NEAR THE SHORELINE. SOUTHWESTERLY FLOW BECOMES
ESTABLISHED ON THURSDAY AS A COLD FRONT APPROACHES FROM THE
NORTHWEST AND THE WEST ATLANTIC HIGH ALSO STRENGTHENS SOMEWHAT. NOT
LOOKING FOR SEAS TO INCREASE AS A RESULT OF THE NEW FLOW REGIME ON
ACCOUNT OF HOW WEAK WIND SPEEDS STAY PLUS THE FACT THAT NO
SIGNIFICANT SWELL ENERGY FOUND ANYWHERE OVER THE WEST ATLANTIC.
LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 300 AM TUESDAY...A COLD FRONT WILL APPROACH FROM THE WEST ON
FRIDAY ALBEIT VERY SLOWLY. THERE WILL BE VERY LITTLE GRADIENT FLOW
AHEAD OF THE BOUNDARY AND NOT MUCH BEHIND IT EITHER. IT WILL STALL
RIGHT ALONG THE COASTLINE EARLY SATURDAY AND MAY EVEN DRIFT A BIT
INLAND AS THE DAY WEARS ON. THIS KEEPS A SOUTHERLY COMPONENT TO THE
FLOW THROUGH THE ENTIRE PERIOD WITH SPEEDS HARD-PRESSED TO EXCEED 10
KT. THERE MAY BE VACILLATIONS IN DIRECTION OF THE SRLY FLOW FROM SE
TO SW AT TIMES ESPECIALLY ALONG THE COAST WITH SEA BREEZE
CIRCULATIONS. WITH SUCH LIGHT WINDS AND NO SWELL ENERGY TO SPEAK OF
SEAS WILL REMAIN MINIMAL, CAPPED AT 2 FT.
&&
.TIDES/COASTAL FLOODING...
AS OF 600 AM TUESDAY...WE DO EXPECT THE NEXT SEVERAL HIGH TIDES TO
BRING A PERIOD OF MINOR COASTAL FLOODING TO THE LOWER CAPE FEAR
RIVER AREA...PERHAPS EVEN INTO LATE WEEK AS THE ASTRONOMICAL TIDE
SLOWLY WANES. THIS MORNING...THE DOWNTOWN WILMINGTON TIDE GAUGE IS
EXPECTED TO REACH NEAR 6 FT. HIGH TIDE IS AT 1030 AM AND 11 PM.
THE BEACHES WILL ALSO EXPERIENCE HIGHER THAN NORMAL TIDES...BUT
DEPARTURES AT HIGH TIDE ARE NOT EXPECTED TO BE SIGNIFICANT AND NO
COASTAL FLOODING IS EXPECTED ON THE OCEANFRONT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...COASTAL FLOOD ADVISORY UNTIL NOON EDT TODAY FOR NCZ107.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...MRR
TIDES/COASTAL FLOODING...RJD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
710 AM EDT TUE SEP 9 2014
.SYNOPSIS... LOW PRESSURE WILL MOVE SLOWLY NORTHEAST ACROSS EASTERN
NORTH CAROLINA THIS MORNING AND OFF THE NORTHEAST COAST OF THE STATE
THIS AFTERNOON. HIGH PRESSURE WILL EXTEND INTO THE REGION TONIGHT
THROUGH EARLY THURSDAY BEFORE ANOTHER COLD FRONT APPROACHES THE
REGION.
&&
.NEAR TERM /TODAY THROUGH TONIGHT/...
AS OF 310 AM TUESDAY...
AFTER A VERY WET DAY WITH NUMEROUS REPORTS OF FLOODING... A SLOW
IMPROVEMENT FROM SW TO NE IS EXPECTED TODAY/TONIGHT OVER CENTRAL NC.
THE REMAINDER OF THE FLASH FLOOD WATCH WILL BE CANCELLED WITH THIS
FORECAST PACKAGE... HOWEVER THERE COULD STILL BE WATER ON ROADS IN
MANY SPOTS THROUGH THE MORNING RUSH HOUR.
LATEST SURFACE MAP SHOWS A SURFACE LOW BETWEEN GSB AND FAY...
TRACKING VERY SLOWLY NE ALONG THE FRONTAL ZONE OVER THE NC/SC
COASTAL PLAIN. RAIN COVERAGE OVER THE FORECAST AREA HAS DECREASED
MARKEDLY SINCE MID EVENING AS DEEP STRONG LIFT HAS WANED... WITH THE
DEPARTURE OF A POTENT MID LEVEL VORTICITY CENTER (NOW OVER ERN NC)
TO THE NE... AND THE RIGHT ENTRANCE REGION OF THE UPPER JET BASED
OVER NEW ENGLAND IS ALSO EXITING... IN CONJUNCTION WITH THE HIGH 2"+
PRECIP WATER. BUT LOW LEVEL MOIST ISENTROPIC UPGLIDE PERSISTS AT 295-
300K OVER THE NORTHEAST CWA... AND THIS IS EXPECTED TO BE VERY SLOW
TO END FROM SW TO NE THROUGH THE DAY... FOLLOWING THE LATEST HRRR
RUNS WHICH HAVE PERFORMED FAIRLY WELL IN THE LAST 24 HRS. BUFR
SOUNDINGS FROM THE GFS/NAM SHOW THE LOW STRATUS DISSOLVING FROM MID
MORNING THROUGH EARLY AFTERNOON... AND WHILE THE PATTERN SEEMS
GOOD... IT LOOKS A LITTLE FAST BASED ON THE ANTICIPATED CONTINUED
ADVECTION OF MOIST LOW LEVEL (SURFACE-925 MB) AIR FROM THE NE (SEEN
ON 00Z UPPER AIR ANALYSES) INTO CENTRAL NC. SO WILL RETAIN LOW
CHANCE POPS FOR PATCHY RAIN/DRIZZLE OVER THE NRN/ERN CWA THROUGH THE
MORNING WITH A SLOW EXIT THIS AFTERNOON... AND HAVE SLOWED THE
GRADUAL CLEARING BY A FEW HOURS AS WELL. THE WRN AND SRN PORTIONS OF
CENTRAL NC HAVE THE BEST CHANCE OF SEEING DECENT SUNSHINE THIS
AFTERNOON... WHILE THE LONGER-LIVED CLOUDS IN THE FAR NRN AND NE CWA
WILL SUPPRESS THE TEMP RISE TODAY. EXPECT HIGHS FROM 75 NEAR KERR
LAKE TO 82 IN THE SW INCLUDING WADESBORO. THE SURFACE LOW CONTINUES
ITS SLOW TREK OVER NE NC AND OFF THE VA TIDEWATER THIS EVENING... AS
THE LOW LEVEL NNE FLOW CONTINUES TO DRAW IN MOISTURE FROM THE
DELMARVA AND SE VA. REDEVELOPMENT OF LOW CLOUDS BY LATE EVENING OVER
THE NE CWA APPEARS LIKELY... AND THE RAP HINTS AT MORE PATCHY
DRIZZLE OVERNIGHT OVER THE NE CWA. GIVEN THE LIGHT DIFFLUENT NATURE
OF SURFACE WINDS TO REINFORCE STABILITY IN THE LOWEST 50-100 MB...
THIS SEEMS PLAUSIBLE. WILL KEEP AT LEAST PARTLY CLOUDY SKIES OVER
THE ENTIRE CWA THROUGH TONIGHT... BUT MOSTLY CLOUDY IN THE FAR NORTH
AND NORTHEAST. LOWS 63-67. -GIH
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 310 AM TUESDAY...
EXPECT QUIET WEATHER WED/WED NIGHT. THE PARENT HIGH NE OF NEW
ENGLAND WILL CONTINUE SHIFTING AWAY FROM THE AREA... LEAVING JUST A
WEAK RESIDUAL SURFACE RIDGE ACROSS CENTRAL/WRN NC. MID LEVEL HEIGHTS
WILL SLOWLY RISE AS THE SHORTWAVE TROUGH MOVES OUT OVER THE NW
ATLANTIC... AND AHEAD OF TROUGHING OVER THE NW/NCNTRL CONUS.
FORECAST SOUNDINGS SHOW DRY/STABLE MID LEVELS... BUT SCATTERED TO
BROKEN FLAT DIURNAL CLOUDS ARE LIKELY IN THE AFTERNOON... YIELDING
PARTLY CLOUDY SKIES OVER MOST OF THE AREA. THICKNESSES RECOVER AND
WITH DAYTIME HEATING... WE SHOULD SEE HIGHS CLOSE TO SEASONAL
NORMALS... 83-87. LOWS 65-69. -GIH
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 305 AM TUESDAY...
UNSETTLED PERIOD EXPECTED FOR THE MUCH OF THE LONG TERM.
THE UPPER AIR PATTERN AT THE BEGINNING OF THE EXTENDED RANGE
FEATURES AN ELONGATED WEAK RIDGE ALOFT EXTENDING FROM THE NORTHERN
GULF OF MEXICO ACROSS THE SOUTHEAST WITH A DEVELOPING LONG WAVE
TROUGH ACROSS THE CENTRAL CONUS THAT DEVELOPS IN RESPONSE TO RIDGING
ACROSS THE NORTHERN PACIFIC. AN INITIAL SHORTWAVE TROUGH WITH A 65+
KT JET AT 500 HPA MOVES ACROSS THE EASTERN GREAT LAKES AND NORTHEAST
ON THURSDAY WITH THE ASSOCIATED COLD FRONT MOVING ACROSS THE
SOUTHERN APPALACHIANS. NWP GUIDANCE DIFFERS IN THE SOUTHWARD PUSH OF
THE FRONT WITH THE GFS PUSHING THE FRONT THROUGH ALL OF NC AND
SETTLING NEAR OR JUST SOUTH OF KCHS AT 12Z SAT WHILE THE ECMWF
STALLS THE FRONT ACROSS CENTRAL NC. A SUBSEQUENT SHORT WAVE TROUGH
IS PROGGED TO MOVE ACROSS THE MIDWEST INTO THE GREAT LAKES LATE
SATURDAY WITH AN ADDITIONAL SHORT WAVE PROGGED TO PASS ALONG A
SIMILAR COURSE LATE SUNDAY AND TUESDAY. GUIDANCE FROM BOTH THE GFS
OR EC KEEPS THE FRONT ACROSS OR JUST SOUTH OF CENTRAL NC THROUGH
MUCH OF THE PERIOD. THE LAST FEW RUNS OF THE LARGER SCALE NWP
GUIDANCE HAS TENDED TO KEEP THE SHORTWAVE ENERGY NORTH OF OUR REGION
WHICH WOULD TEND TO FAVOR A SURFACE FRONT THAT IS LESS LIKELY TO
PUSH INTO THE DEEP SOUTH. IN ADDITION...THE LATEST DISCUSSION FROM
WPC CONTINUES TO SUPPORT A LESS PROGRESSIVE PATTERN.
THE RESULT IS A PATTERN THAT WOULD SUPPORT AN UNSETTLED PERIOD BUT
ONE IN WHICH CONFIDENCE ON FORECAST DETAILS...ESPECIALLY LATE IN
LONG TERM IS LOWER THAN TYPICAL. FOR NOW WILL ADVERTISE AN INCREASE
IN THE CHANCE OF SHOWERS AND THUNDERSTORMS LATE THURSDAY AND
ESPECIALLY ON FRIDAY AND SATURDAY WITH THE THUNDERSTORM ACTIVITY
INCREASINGLY CONFINED TO LOCATIONS FURTHER SOUTH THROUGH THE PERIOD
AS COOLER AND MORE STABLE AIR MOVES INTO THE REGION. THE EVENTUAL
FRONTAL POSITION WILL DETERMINE THE DISTRIBUTION OF POPS AND
TEMPERATURES ALTHOUGH A DOWNWARD TREND IN TEMPERATURES IS EXPECTED
THROUGH THE PERIOD WITH TEMPERATURES GENERALLY BECOMING BELOW
AVERAGE BY FRIDAY OR SATURDAY. THE AMOUNT OF CONVECTIVE COVERAGE
OVER THE WEEKEND INTO MONDAY IS STILL UNCERTAIN BUT IN GENERAL THE
CHANCE OF PRECIPITATION WILL GENERALLY DECREASE THROUGH THE PERIOD
AND SHIFT SOUTHEAST WITH TIME. -BLAES
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
AS OF 710 AM TUESDAY...
IFR CIGS AND MVFR VSBYS ARE LIKELY TO DOMINATE AT ALL TAF SITES
THROUGH NOON. IMPROVEMENT TO MVFR THEN VFR IS EXPECTED AT INT/GSO
FROM 15Z-18Z... AT RDU/FAY 17Z-20Z... AND AT RWI 19Z-22Z. MVFR-IFR
CIGS MAY RETURN AT RDU/RWI AFTER 04Z TONIGHT.
A SURFACE LOW PRESSURE CURRENTLY LOCATED NEAR GSB WILL CONTINUE
MOVING SLOWLY TOWARD THE NE THIS MORNING... TRACKING ALONG A FRONTAL
ZONE ACROSS OUR SOUTHEAST COUNTIES. SURFACE WINDS FROM THE N AND NE
OVER CENTRAL NC HAVE KEPT A FLOW OF MOIST LOW LEVEL ATLANTIC AIR
ADVECTING INTO THE REGION. WIDESPREAD RAIN AND DRIZZLE WILL LINGER
OVER NORTHEAST SECTIONS IMPACTING RDU/RWI THROUGH SUNRISE. THIS WILL
BE FOLLOWED BY A SLOW TAPERING OFF OF THIS RAIN/DRIZZLE FROM SW TO
NE THROUGH LATE MORNING / EARLY AFTERNOON... WITH VSBYS REBOUNDING
TO VFR ALSO FROM SW TO NE THROUGH THE AFTERNOON. WEAK HIGH PRESSURE
WILL EXTEND OVER THE REGION STARTING THIS EVENING... RESULTING IN
WINDS BECOMING LIGHT... AND WITH THESE LIGHT WINDS AND A WET
GROUND... REDEVELOPMENT OF IFR/LIFR LOW CLOUDS AND FOG IS EXPECTED
TONIGHT... PRIMARILY AT RDU/RWI BUT POTENTIALLY AT GSO/INT/FAY AS
WELL... BEGINNING NEAR OR SOON AFTER MIDNIGHT.
LOOKING BEYOND 12Z EARLY WED MORNING... SUB-VFR CIGS SHOULD HOLD
MAINLY AT RDU/RWI UNTIL AROUND 13Z-14Z... THEN THESE CLOUDS WILL MIX
OUT WITH HEATING... AND VFR CONDITIONS ARE EXPECTED AT ALL TAF SITES
AFTER 16Z WED... LASTING THROUGH THU NIGHT. MVFR-IFR STRATUS IS
POSSIBLE LATE THU NIGHT INTO FRI AS A COLD FRONT APPROACHES FROM THE
NW. SUB-VFR CONDITIONS AND PERIODS OF RAIN ARE EXPECTED TO DOMINATE
FRI THROUGH SAT AS THE FRONT STALLS OVER THE REGION. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BLAES
NEAR TERM...HARTFIELD
SHORT TERM...HARTFIELD
LONG TERM...BLAES
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
653 AM EDT TUE SEP 9 2014
.SYNOPSIS...
A LINGERING FRONT ALONG THE COAST WILL FINALLY PUSH WELL SOUTH AND
EAST OF THE AREA TONIGHT. DRIER AIR WILL SLOWLY ARRIVE TODAY...WITH
DRY AND WARM CONDITIONS WEDNESDAY AND THURSDAY. A COLD FRONT WILL
ARRIVE LATE WEEK...DRIFTING SOUTH EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 600 AM TUESDAY...A COLD FRONT HAS PUSHED JUST OFFSHORE NEAR
DAYBREAK...BUT IS EXPECTED TO REMAIN IN CLOSE PROXIMITY TO THE COAST
THROUGH THE DAY. THE PROXIMITY OF THE FRONT NECESSITATES A VERY
SMALL MENTION OF A SHOWER TODAY...BUT NO SIGNIFICANT PRECIPITATION
IS EXPECTED ACROSS THE FORECAST AREA. A SERIES OF SHORTWAVES WILL
MOVE UP ALONG THE COAST TODAY AND AS THE LAST IN THE SERIES MOVES TO
OUR NORTHEAST...THE FRONT SHOULD FINALLY GET KICKED TO OUR SOUTH AND
EAST TONIGHT.
THE CORRIDOR OF DEEPEST MOISTURE AND HEAVIEST RAIN HAS SHIFTED OFF
THE COAST AND THE NATIONAL WEATHER SERVICE HAS CANCELLED THE FLOOD
WATCH. WATER VAPOR IMAGERY INDICATES THE REALLY DRY AIR ACROSS THE
UPSTATE OF SOUTH CAROLINA AND WESTERN NORTH CAROLINA THIS MORNING...
STRUGGLING TO PUSH EAST. THE COLUMN WILL BEGIN TO SIGNIFICANTLY
DRY...FIRST INLAND WHERE A DEEPENING WEST TO NORTHWEST FLOW WILL
TAKE HOLD AND THEN ALONG THE COAST. WE WILL SEE PRECIPITABLE WATER
VALUES DROP FROM NEAR 2 INCHES THIS MORNING TO LESS THAN AN INCH AND
A HALF TONIGHT WITH THE MID LEVELS EXPERIENCING THE BIGGEST PUNCH OF
DRY AIR. THIS SHOULD FINALLY ALLOW MORE LATE SUMMER SUNSHINE TO VERY
SLOWLY DEVELOP. HOWEVER...IT WILL TAKE A GOOD PART OF THE DAY AS LOW
LEVEL MOISTURE WILL REMAIN TRAPPED UNDERNEATH A SUBSIDENCE INVERSION
THIS MORNING. WIDESPREAD LOW STRATUS IS EXPECTED TO GIVE WAY TO
PARTIAL SUNSHINE THIS AFTERNOON FROM SOUTHWEST TO NORTHEAST WITH
THICK CLOUDS LIKELY LINGERING ALONG THE COAST THROUGH MUCH OF THE
AFTERNOON.
LINGERING CLOUDS WILL HAVE AN IMPACT ON HIGH TEMPS TODAY. WHERE SOME
SUNSHINE IS ABLE TO DEVELOP LONGEST...WE EXPECT HIGHS TO REACH THE
MID 80S. CURRENTLY...THIS SEEMS MOST PROBABLE ACROSS THE PEE DEE
REGION. OTHERWISE...HIGHS SHOULD ONLY REACH THE LOWER 80S WITH
PERHAPS ONLY 80 FOR A GOOD PORTION OF SOUTHEAST NORTH CAROLINA. THE
TREND TOWARD LESS CLOUD COVER WILL ACCELERATE ALONG THE COAST
TONIGHT. LOW LEVEL MOISTURE WILL RESIST BEING REMOVED...BUT THE
TREND WILL BE FOR DEWPOINTS TO GRADUALLY LOWER. WILL FORECAST LOWS
IN THE MID AND UPPER 60S WITH LOWER 70S HOLDING ON AT THE BEACHES.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 AM TUESDAY...ZONAL MID LEVEL FLOW AND A DISSIPATING
SURFACE HIGH ON WEDNESDAY WILL BRING A DRY DAY WITH NEAR SEASONABLE
TEMPERATURES. ON THURSDAY THE APPROACH OF A COLD FRONT AND A SLIGHT
STRENGTHENING OF THE WEST ATLANTIC HIGH WILL BOOST THE AFTERNOON
WARMTH AS WELL SLIGHTLY MOISTEN THE LOW LEVELS OF THE ATMOSPHERE.
MOST PLACES AWAY FROM THE IMMEDIATE COASTLINE SHOULD WARM INTO THE
LOW 90S. THE MORE NOTICEABLE DIFFERENCE BETWEEN THE TWO DAYS WILL BE
THE AFTERNOON APPARENT TEMPERATURES.ON WEDNESDAY MOST PLACES WILL
TOP OUT AROUND 90 DEGREES BUT AS THE DEWPOINTS RISE THURSDAY THE
HEAT INDICES WILL BE IN THE UPPER 90S. BOTH DAYS THIS EFFECT WILL BE
CONSIDERABLY TAPERED ALONG THE COAST. MODELS TRENDING A BIT FASTER
WITH MOISTURE RETURN AHEAD OF NEXT COLD FRONT ESP THE GFS. WILL PUT
LOW POPS IN TOWARDS THE END OF THE PERIOD.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 300 AM TUESDAY...COLD FRONT ENTERS THE AREA ON FRIDAY AND MAY
TAKE A FULL 24 HOURS TO THEN BE ORIENTED RIGHT ALONG THE COAST LINE.
THIS SHOULD KEEP THINGS QUITE UNSETTLED FRIDAY AND PROBABLY SATURDAY
AS WELL. MODELS CANNOT SEEM TO DECIDE WHERE THE CORE OF THE COOL AIR
GOES HOWEVER. NORMALLY IN EARLY SEPTEMBER THIS ISN`T TOO BIG A DEAL
AS COOL FRONTS USUALLY JUST REPRESENT A DROP IN HUMIDITY THIS FAR
SOUTH. HOWEVER THIS COLD FRONT WILL HAVE SOME CONSIDERABLY COOLER
AND DRIER AIR AND THE GFS IN PARTICULAR IS NOW HESITANT TO SHOVE IT
THIS FAR SOUTH. INSTEAD THE MODEL KEEPS THE SECONDARY FRONT...THE
MUCH COOLER AIR...OFF TO OUR NORTH AND WEST WHILE THE LEADING AND
MUCH WEAKER FRONT MEANDERS AND WEAKENS NEAR THE COAST FOR THE REST
OF THE PERIOD. THE ADDED CLOUD COVER THAT THE FRONT WOULD YIELD
WOULD KEEP TEMPS DOWN AND THERE WILL STILL BE AN AIRMASS CHANGE FROM
THE SHORT TERM PERIOD TO BE SURE...BUT I`M NO LONGER CERTAIN WE`RE
IN FOR A `REFRESHING` AIRMASS THAT WE NORMALLY EXPERIENCE MUCH LATER
IN THE MONTH OR EVEN OCTOBER. A GLANCE AT THE NEW 00Z ECMWF WOULD
IMPLY THAT THE LATE PERIOD COOLDOWN WHILE STILL PRESENT...MAY NOT BE
VERY NOTEWORTHY.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 06Z...SHOWER ACTIVITY HAS TRANSITIONED OFFSHORE...AND THE
LATEST HRRR RUNS SUGGEST THE COASTAL SITES WILL SEE MINIMAL IF ANY
PCPN IMPACTS AFTER 06Z. EXPECT MVFR/IFR STRATUS TO PERSIST OVERNIGHT
AS COOLER AIR WRAPS AROUND LOW PRESSURE MOVING ALONG A NEAR
STATIONARY FRONT. BASED ON THE LATEST OBS AND SREF PROBABILITIES...
THE BEST CHANCES FOR IFR CIGS WILL BE INLAND AT KLBT/KFLO. THE
COASTAL TERMINALS MAY ALSO SEE AT LEAST TEMPO IFR CIGS. LIGHT
NORTHWEST WINDS INLAND WILL BECOME MORE NORTHERLY DURING THE DAY.
ALONG THE COAST...WIND DIRECTIONS MAY BECOME VRBL AS THE FRONT
WAVERS NEAR THE AREA. MVFR STRATOCU SHOULD PERSIST THROUGH MUCH OF
THE MORNING. BUT FCST SOUNDINGS DO DEPICT A DRYING TREND BY THE AFTN
HOURS...SO EXPECT CONDITIONS WILL IMPROVE TO VFR FROM SW TO NE AFTER
MIDDAY.
EXTENDED OUTLOOK...VFR WILL PREVAIL WEDNESDAY AND THURSDAY. SHOWERS
AND TSTMS RETURN FRIDAY AND SATURDAY AS ANOTHER COLD FRONT NEARS THE
CAROLINAS.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 600 AM TUESDAY...A FRONT WILL REMAIN IN THE VICINITY TODAY
AND THEN FINALLY MOVE EAST AND SOUTH OF THE WATERS TONIGHT. THIS
WILL KEEP WINDS LIGHT ACROSS THE WATERS...UP TO 10 TO 15 KT THIS
MORNING FOR THE NORTHERNMOST WATERS...OTHERWISE 10 KT OR LESS
THROUGHOUT THROUGH TONIGHT. THE DIRECTION WILL PRIMARILY BE
SOUTHWEST TO WEST SOUTHWEST TODAY WITH WINDS SHIFTING TO NORTHWEST
AND NORTH WITH A CLEAR FRONTAL PASSAGE TONIGHT. SEAS WILL BE HIGHEST
THIS MORNING...UP TO 3 TO 4 FT...SUBSIDING TO 3 FT OR LESS THIS
AFTERNOON AND 2 FT OR LESS TONIGHT.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 AM TUESDAY...WIND AND SEAS BOTH MINIMAL ON WEDNESDAY. HIGH
PRESSURE INITIALLY OVER THE LANDMASS WEDNESDAY WASHES OUT AS THE DAY
WEARS ON. NE FLOW TO START THE DAY WILL GIVE TO WAY LIGHT AND
SOMEWHAT VARIABLE FLOW POSSIBLY EVEN DOMINATED BY MESOSCALE SEA
BREEZE AT LEAST NEAR THE SHORELINE. SOUTHWESTERLY FLOW BECOMES
ESTABLISHED ON THURSDAY AS A COLD FRONT APPROACHES FROM THE
NORTHWEST AND THE WEST ATLANTIC HIGH ALSO STRENGTHENS SOMEWHAT. NOT
LOOKING FOR SEAS TO INCREASE AS A RESULT OF THE NEW FLOW REGIME ON
ACCOUNT OF HOW WEAK WIND SPEEDS STAY PLUS THE FACT THAT NO
SIGNIFICANT SWELL ENERGY FOUND ANYWHERE OVER THE WEST ATLANTIC.
LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 300 AM TUESDAY...A COLD FRONT WILL APPROACH FROM THE WEST ON
FRIDAY ALBEIT VERY SLOWLY. THERE WILL BE VERY LITTLE GRADIENT FLOW
AHEAD OF THE BOUNDARY AND NOT MUCH BEHIND IT EITHER. IT WILL STALL
RIGHT ALONG THE COASTLINE EARLY SATURDAY AND MAY EVEN DRIFT A BIT
INLAND AS THE DAY WEARS ON. THIS KEEPS A SOUTHERLY COMPONENT TO THE
FLOW THROUGH THE ENTIRE PERIOD WITH SPEEDS HARD-PRESSED TO EXCEED 10
KT. THERE MAY BE VACILLATIONS IN DIRECTION OF THE SRLY FLOW FROM SE
TO SW AT TIMES ESPECIALLY ALONG THE COAST WITH SEA BREEZE
CIRCULATIONS. WITH SUCH LIGHT WINDS AND NO SWELL ENERGY TO SPEAK OF
SEAS WILL REMAIN MINIMAL, CAPPED AT 2 FT.
&&
.TIDES/COASTAL FLOODING...
AS OF 600 AM TUESDAY...WE DO EXPECT THE NEXT SEVERAL HIGH TIDES TO
BRING A PERIOD OF MINOR COASTAL FLOODING TO THE LOWER CAPE FEAR
RIVER AREA...PERHAPS EVEN INTO LATE WEEK AS THE ASTRONOMICAL TIDE
SLOWLY WANES. THIS MORNING...THE DOWNTOWN WILMINGTON TIDE GAUGE IS
EXPECTED TO REACH NEAR 6 FT. HIGH TIDE IS AT 1030 AM AND 11 PM.
THE BEACHES WILL ALSO EXPERIENCE HIGHER THAN NORMAL TIDES...BUT
DEPARTURES AT HIGH TIDE ARE NOT EXPECTED TO BE SIGNIFICANT AND NO
COASTAL FLOODING IS EXPECTED ON THE OCEANFRONT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...COASTAL FLOOD ADVISORY UNTIL NOON EDT TUESDAY FOR NCZ107.
MARINE...NONE.
&&
$$
NEAR TERM...RJD
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...BJR/RJD
TIDES/COASTAL FLOODING...RJD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
330 AM EDT TUE SEP 9 2014
.SYNOPSIS...
DRIER AIR WILL ARRIVE TODAY AS LOW PRESSURE MOVES FURTHER UP THE
MID-ATLANTIC COAST. WARMER TEMPERATURES AND DRY WEATHER ARE EXPECTED
WEDNESDAY AND THURSDAY. A STRONG COLD FRONT WILL ARRIVE LATE WEEK...
DRIFTING SOUTH EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM TUESDAY...THE CORRIDOR OF DEEPEST MOISTURE AND HEAVIEST
RAIN HAS SHIFTED OFF THE COAST AND THE NATIONAL WEATHER SERVICE HAS
CANCELLED THE FLOOD WATCH. AN ASTRONOMICAL HIGH TIDE WILL STILL
BRING A BRIEF PERIOD OF MINOR COASTAL FLOODING FOR PORTION OF THE
LOWER CAPE FEAR RIVER. HIGH TIDE AT WILMINGTON IS NEAR 1030 AM AND
11 PM. THE BEACHES WILL ALSO EXPERIENCE HIGHER THAN NORMAL
TIDES...BUT DEPARTURES OF ABOUT A HALF FOOT SHOULD NOT BE ENOUGH TO
PRODUCE MINOR COASTAL FLOODING.
A COLD FRONT WAS POSITIONED JUST WEST OF ILM AND ALONG THE GRAND
STRAND BEACHES EARLY THIS MORNING. HOWEVER...THIS FRONT WILL NOT BE
MOVING MUCH TODAY. A SERIES OF SHORTWAVES WILL MOVE UP ALONG THE
COAST TODAY AND AS THE LAST IN THE SERIES MOVES TO OUR NORTHEAST...
THE FRONT SHOULD FINALLY GET KICKED TO OUR SOUTH AND EAST TONIGHT.
WILL ONLY CARRY A SLIGHT CHANCE OF MEASURABLE RAIN IN SHOWERS ALONG
AND EAST OF A LINE FROM EYF TO NEAR GGE TODAY. ANY PRECIPITATION
WILL BE VERY LIGHT.
THE COLUMN WILL BEGIN TO SIGNIFICANTLY DRY...FIRST INLAND WHERE A
DEEPENING WEST TO NORTHWEST FLOW WILL TAKE HOLD FIRST AND THEN ALONG
THE COAST. WE WILL SEE PRECIPITABLE WATER VALUES DROP FROM NEAR 2
INCHES THIS MORNING TO LESS THAN AN INCH AND A HALF TONIGHT WITH THE
MID LEVELS EXPERIENCING THE BIGGEST PUNCH OF DRY AIR. THIS SHOULD
FINALLY ALLOW MORE LATE SUMMER SUNSHINE TO VERY SLOWLY DEVELOP.
HOWEVER...IT WILL TAKE A GOOD PART OF THE DAY AS LOW LEVEL MOISTURE
WILL REMAIN TRAPPED UNDERNEATH A SUBSIDENCE INVERSION THIS MORNING.
WIDESPREAD LOW STRATUS IS EXPECTED TO GIVE WAY TO PARTIAL SUNSHINE
THIS AFTERNOON FROM SOUTHWEST TO NORTHEAST WITH THICK CLOUDS LIKELY
LINGERING ALONG THE COAST THROUGH MUCH OF THE AFTERNOON.
LINGERING CLOUDS WILL HAVE AN IMPACT ON HIGH TEMPS TODAY. WHERE SOME
SUNSHINE IS ABLE TO DEVELOP LONGEST...WE EXPECT HIGHS TO REACH THE
MID 80S. CURRENTLY...THIS SEEMS MOST PROBABLE ACROSS THE PEE DEE
REGION. OTHERWISE...HIGHS SHOULD ONLY REACH THE LOWER 80S WITH
PERHAPS ONLY 80 FOR A GOOD PORTION OF SOUTHEAST NORTH CAROLINA. THE
TREND TOWARD LESS CLOUD COVER WILL ACCELERATE ALONG THE COAST
TONIGHT. LOW LEVEL MOISTURE WILL RESIST BEING REMOVED...BUT THE
TREND WILL BE FOR DEWPOINTS TO GRADUALLY LOWER. WILL FORECAST LOWS
IN THE MID AND UPPER 60S WITH LOWER 70S HOLDING ON AT THE BEACHES.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 AM TUESDAY...ZONAL MID LEVEL FLOW AND A DISSIPATING SURFACE
HIGH ON WEDNESDAY WILL BRING A DRY DAY WITH NEAR SEASONABLE
TEMPERATURES. ON THURSDAY THE APPROACH OF A COLD FRONT AND A SLIGHT
STRENGTHENING OF THE WEST ATLANTIC HIGH WILL BOOST THE AFTERNOON
WARMTH AS WELL SLIGHTLY MOISTEN THE LOW LEVELS OF THE ATMOSPHERE.
MOST PLACES AWAY FROM THE IMMEDIATE COASTLINE SHOULD WARM INTO THE
LOW 90S. THE MORE NOTICEABLE DIFFERENCE BETWEEN THE TWO DAYS WILL BE
THE AFTERNOON APPARENT TEMPERATURES.ON WEDNESDAY MOST PLACES WILL
TOP OUT AROUND 90 DEGREES BUT AS THE DEWPOINTS RISE THURSDAY THE
HEAT INDICES WILL BE IN THE UPPER 90S. BOTH DAYS THIS EFFECT WILL BE
CONSIDERABLY TAPERED ALONG THE COAST. MODELS TRENDING A BIT FASTER
WITH MOISTURE RETURN AHEAD OF NEXT COLD FRONT ESP THE GFS. WILL PUT
LOW POPS IN TOWARDS THE END OF THE PERIOD.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 3 AM TUESDAY...COLD FRONT ENTERS THE AREA ON FRIDAY AND MAY
TAKE A FULL 24 HOURS TO THEN BE ORIENTED RIGHT ALONG THE COAST LINE.
THIS SHOULD KEEP THINGS QUITE UNSETTLED FRIDAY AND PROBABLY SATURDAY
AS WELL. MODELS CANNOT SEEM TO DECIDE WHERE THE CORE OF THE COOL AIR
GOES HOWEVER. NORMALLY IN EARLY SEPTEMBER THIS ISN`T TOO BIG A DEAL
AS COOL FRONTS USUALLY JUST REPRESENT A DROP IN HUMIDITY THIS FAR
SOUTH. HOWEVER THIS COLD FRONT WILL HAVE SOME CONSIDERABLY COOLER
AND DRIER AIR AND THE GFS IN PARTICULAR IS NOW HESITANT TO SHOVE IT
THIS FAR SOUTH. INSTEAD THE MODEL KEEPS THE SECONDARY FRONT...THE
MUCH COOLER AIR...OFF TO OUR NORTH AND WEST WHILE THE LEADING AND
MUCH WEAKER FRONT MEANDERS AND WEAKENS NEAR THE COAST FOR THE REST
OF THE PERIOD. THE ADDED CLOUD COVER THAT THE FRONT WOULD YIELD
WOULD KEEP TEMPS DOWN AND THERE WILL STILL BE AN AIRMASS CHANGE FROM
THE SHORT TERM PERIOD TO BE SURE...BUT I`M NO LONGER CERTAIN WE`RE
IN FOR A `REFRESHING` AIRMASS THAT WE NORMALLY EXPERIENCE MUCH LATER
IN THE MONTH OR EVEN OCTOBER. A GLANCE AT THE NEW 00Z ECMWF WOULD
IMPLY THAT THE LATE PERIOD COOLDOWN WHILE STILL PRESENT...MAY NOT BE
VERY NOTEWORTHY.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 06Z...SHOWER ACTIVITY HAS TRANSITIONED OFFSHORE...AND THE
LATEST HRRR RUNS SUGGEST THE COASTAL SITES WILL SEE MINIMAL IF ANY
PCPN IMPACTS AFTER 06Z. EXPECT MVFR/IFR STRATUS TO PERSIST OVERNIGHT
AS COOLER AIR WRAPS AROUND LOW PRESSURE MOVING ALONG A NEAR
STATIONARY FRONT. BASED ON THE LATEST OBS AND SREF PROBABILITIES...
THE BEST CHANCES FOR IFR CIGS WILL BE INLAND AT KLBT/KFLO. THE
COASTAL TERMINALS MAY ALSO SEE AT LEAST TEMPO IFR CIGS. LIGHT
NORTHWEST WINDS INLAND WILL BECOME MORE NORTHERLY DURING THE DAY.
ALONG THE COAST...WIND DIRECTIONS MAY BECOME VRBL AS THE FRONT
WAVERS NEAR THE AREA. MVFR STRATOCU SHOULD PERSIST THROUGH MUCH OF
THE MORNING. BUT FCST SOUNDINGS DO DEPICT A DRYING TREND BY THE AFTN
HOURS...SO EXPECT CONDITIONS WILL IMPROVE TO VFR FROM SW TO NE AFTER
MIDDAY.
EXTENDED OUTLOOK...VFR WILL PREVAIL WEDNESDAY AND THURSDAY. SHOWERS
AND TSTMS RETURN FRIDAY AND SATURDAY AS ANOTHER COLD FRONT NEARS THE
CAROLINAS.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM TUESDAY...A FRONT WILL REMAIN IN THE VICINITY TODAY
AND THEN FINALLY MOVE EAST AND SOUTH OF THE WATERS TONIGHT. THIS
WILL KEEP WINDS LIGHT ACROSS THE WATERS...UP TO 10 TO 15 KT THIS
MORNING FOR THE NORTHERNMOST WATERS...OTHERWISE 10 KT OR LESS
THROUGHOUT THROUGH TONIGHT. THE DIRECTION WILL PRIMARILY BE
SOUTHWEST TO WEST SOUTHWEST TODAY WITH WINDS SHIFTING TO NORTHWEST
AND NORTH WITH FRONTAL PASSAGE TONIGHT. SEAS WILL BE HIGHEST THIS
MORNING...UP TO 3 TO 4 FT...SUBSIDING TO 3 FT OR LESS THIS AFTERNOON
AND 2 FT OR LESS TONIGHT.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 AM TUESDAY...WIND AND SEAS BOTH MINIMAL ON WEDNESDAY. HIGH
PRESSURE INITIALLY OVER THE LANDMASS WEDNESDAY WASHES OUT AS THE DAY
WEARS ON. NE FLOW TO START THE DAY WILL GIVE TO WAY LIGHT AND
SOMEWHAT VARIABLE FLOW POSSIBLY EVEN DOMINATED BY MESOSCALE SEA
BREEZE AT LEAST NEAR THE SHORELINE. SOUTHWESTERLY FLOW BECOMES
ESTABLISHED ON THURSDAY AS A COLD FRONT APPROACHES FROM THE
NORTHWEST AND THE WEST ATLANTIC HIGH ALSO STRENGTHENS SOMEWHAT. NOT
LOOKING FOR SEAS TO INCREASE AS A RESULT OF THE NEW FLOW REGIME ON
ACCOUNT OF HOW WEAK WIND SPEEDS STAY PLUS THE FACT THAT NO
SIGNIFICANT SWELL ENERGY FOUND ANYWHERE OVER THE WEST ATLANTIC.
LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 3 AM TUESDAY...A COLD FRONT WILL APPROACH FROM THE WEST ON
FRIDAY ALBEIT VERY SLOWLY. THERE WILL BE VERY LITTLE GRADIENT FLOW
AHEAD OF THE BOUNDARY AND NOT MUCH BEHIND IT EITHER. IT WILL STALL
RIGHT ALONG THE COASTLINE EARLY SATURDAY AND MAY EVEN DRIFT A BIT
INLAND AS THE DAY WEARS ON. THIS KEEPS A SOUTHERLY COMPONENT TO THE
FLOW THROUGH THE ENTIRE PERIOD WITH SPEEDS HARD-PRESSED TO EXCEED 10
KT. THERE MAY BE VACILLATIONS IN DIRECTION OF THE SRLY FLOW FROM SE
TO SW AT TIMES ESPECIALLY ALONG THE COAST WITH SEA BREEZE
CIRCULATIONS. WITH SUCH LIGHT WINDS AND NO SWELL ENERGY TO SPEAK OF
SEAS WILL REMAIN MINIMAL, CAPPED AT 2 FT.
&&
.TIDES/COASTAL FLOODING...
AS OF 1200 AM TUESDAY...TIDE LEVELS MEASURED AT THE CAPE FEAR
RIVER DOWNTOWN GAGE HAVE FALLEN BELOW 5.5 FT MLLW...THRESHOLD FOR
MINOR FLOODING ALONG THE CAPE FEAR RIVER FROM WILMINGTON SOUTH TO
CAPE FEAR. AN UPDATED COASTAL FLOOD ADVISORY HAS BEEN ISSUED
ENDING TONIGHTS THREAT. WITH TOMORROW MORNINGS FORECAST HIGH TIDE
GAGE READING ALONG THE CAPE FEAR A THREAT TO BREAK MINOR COASTAL
FLOOD THRESHOLDS ONCE AGAIN...THE COASTAL FLOOD ADVISORY WILL
REMAIN ACTIVE THROUGH NOON TUESDAY TO KEEP PEOPLE ALERT TO THIS
SUCCESSIVE HIGH TIDE FLOOD THREAT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...COASTAL FLOOD ADVISORY UNTIL NOON EDT TUESDAY FOR NCZ107.
MARINE...NONE.
&&
$$
NEAR TERM...DCH/TRA
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...BJR/RJD
TIDES/COASTAL FLOODING...TRA/DCH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
315 AM EDT TUE SEP 9 2014
.SYNOPSIS... LOW PRESSURE WILL MOVE SLOWLY NORTHEAST ACROSS EASTERN
NORTH CAROLINA THIS MORNING AND OFF THE NORTHEAST COAST OF THE STATE
THIS AFTERNOON. HIGH PRESSURE WILL EXTEND INTO THE REGION TONIGHT
THROUGH EARLY THURSDAY BEFORE ANOTHER COLD FRONT APPROACHES THE
REGION.
&&
.NEAR TERM /TODAY THROUGH TONIGHT/...
AS OF 310 AM TUESDAY...
AFTER A VERY WET DAY WITH NUMEROUS REPORTS OF FLOODING... A SLOW
IMPROVEMENT FROM SW TO NE IS EXPECTED TODAY/TONIGHT OVER CENTRAL NC.
THE REMAINDER OF THE FLASH FLOOD WATCH WILL BE CANCELLED WITH THIS
FORECAST PACKAGE... HOWEVER THERE COULD STILL BE WATER ON ROADS IN
MANY SPOTS THROUGH THE MORNING RUSH HOUR.
LATEST SURFACE MAP SHOWS A SURFACE LOW BETWEEN GSB AND FAY...
TRACKING VERY SLOWLY NE ALONG THE FRONTAL ZONE OVER THE NC/SC
COASTAL PLAIN. RAIN COVERAGE OVER THE FORECAST AREA HAS DECREASED
MARKEDLY SINCE MID EVENING AS DEEP STRONG LIFT HAS WANED... WITH THE
DEPARTURE OF A POTENT MID LEVEL VORTICITY CENTER (NOW OVER ERN NC)
TO THE NE... AND THE RIGHT ENTRANCE REGION OF THE UPPER JET BASED
OVER NEW ENGLAND IS ALSO EXITING... IN CONJUNCTION WITH THE HIGH 2"+
PRECIP WATER. BUT LOW LEVEL MOIST ISENTROPIC UPGLIDE PERSISTS AT 295-
300K OVER THE NORTHEAST CWA... AND THIS IS EXPECTED TO BE VERY SLOW
TO END FROM SW TO NE THROUGH THE DAY... FOLLOWING THE LATEST HRRR
RUNS WHICH HAVE PERFORMED FAIRLY WELL IN THE LAST 24 HRS. BUFR
SOUNDINGS FROM THE GFS/NAM SHOW THE LOW STRATUS DISSOLVING FROM MID
MORNING THROUGH EARLY AFTERNOON... AND WHILE THE PATTERN SEEMS
GOOD... IT LOOKS A LITTLE FAST BASED ON THE ANTICIPATED CONTINUED
ADVECTION OF MOIST LOW LEVEL (SURFACE-925 MB) AIR FROM THE NE (SEEN
ON 00Z UPPER AIR ANALYSES) INTO CENTRAL NC. SO WILL RETAIN LOW
CHANCE POPS FOR PATCHY RAIN/DRIZZLE OVER THE NRN/ERN CWA THROUGH THE
MORNING WITH A SLOW EXIT THIS AFTERNOON... AND HAVE SLOWED THE
GRADUAL CLEARING BY A FEW HOURS AS WELL. THE WRN AND SRN PORTIONS OF
CENTRAL NC HAVE THE BEST CHANCE OF SEEING DECENT SUNSHINE THIS
AFTERNOON... WHILE THE LONGER-LIVED CLOUDS IN THE FAR NRN AND NE CWA
WILL SUPPRESS THE TEMP RISE TODAY. EXPECT HIGHS FROM 75 NEAR KERR
LAKE TO 82 IN THE SW INCLUDING WADESBORO. THE SURFACE LOW CONTINUES
ITS SLOW TREK OVER NE NC AND OFF THE VA TIDEWATER THIS EVENING... AS
THE LOW LEVEL NNE FLOW CONTINUES TO DRAW IN MOISTURE FROM THE
DELMARVA AND SE VA. REDEVELOPMENT OF LOW CLOUDS BY LATE EVENING OVER
THE NE CWA APPEARS LIKELY... AND THE RAP HINTS AT MORE PATCHY
DRIZZLE OVERNIGHT OVER THE NE CWA. GIVEN THE LIGHT DIFFLUENT NATURE
OF SURFACE WINDS TO REINFORCE STABILITY IN THE LOWEST 50-100 MB...
THIS SEEMS PLAUSIBLE. WILL KEEP AT LEAST PARTLY CLOUDY SKIES OVER
THE ENTIRE CWA THROUGH TONIGHT... BUT MOSTLY CLOUDY IN THE FAR NORTH
AND NORTHEAST. LOWS 63-67. -GIH
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 310 AM TUESDAY...
EXPECT QUIET WEATHER WED/WED NIGHT. THE PARENT HIGH NE OF NEW
ENGLAND WILL CONTINUE SHIFTING AWAY FROM THE AREA... LEAVING JUST A
WEAK RESIDUAL SURFACE RIDGE ACROSS CENTRAL/WRN NC. MID LEVEL HEIGHTS
WILL SLOWLY RISE AS THE SHORTWAVE TROUGH MOVES OUT OVER THE NW
ATLANTIC... AND AHEAD OF TROUGHING OVER THE NW/NCNTRL CONUS.
FORECAST SOUNDINGS SHOW DRY/STABLE MID LEVELS... BUT SCATTERED TO
BROKEN FLAT DIURNAL CLOUDS ARE LIKELY IN THE AFTERNOON... YIELDING
PARTLY CLOUDY SKIES OVER MOST OF THE AREA. THICKNESSES RECOVER AND
WITH DAYTIME HEATING... WE SHOULD SEE HIGHS CLOSE TO SEASONAL
NORMALS... 83-87. LOWS 65-69. -GIH
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 305 AM TUESDAY...
UNSETTLED PERIOD EXPECTED FOR THE MUCH OF THE LONG TERM.
THE UPPER AIR PATTERN AT THE BEGINNING OF THE EXTENDED RANGE
FEATURES AN ELONGATED WEAK RIDGE ALOFT EXTENDING FROM THE NORTHERN
GULF OF MEXICO ACROSS THE SOUTHEAST WITH A DEVELOPING LONG WAVE
TROUGH ACROSS THE CENTRAL CONUS THAT DEVELOPS IN RESPONSE TO RIDGING
ACROSS THE NORTHERN PACIFIC. AN INITIAL SHORTWAVE TROUGH WITH A 65+
KT JET AT 500 HPA MOVES ACROSS THE EASTERN GREAT LAKES AND NORTHEAST
ON THURSDAY WITH THE ASSOCIATED COLD FRONT MOVING ACROSS THE
SOUTHERN APPALACHIANS. NWP GUIDANCE DIFFERS IN THE SOUTHWARD PUSH OF
THE FRONT WITH THE GFS PUSHING THE FRONT THROUGH ALL OF NC AND
SETTLING NEAR OR JUST SOUTH OF KCHS AT 12Z SAT WHILE THE ECMWF
STALLS THE FRONT ACROSS CENTRAL NC. A SUBSEQUENT SHORT WAVE TROUGH
IS PROGGED TO MOVE ACROSS THE MIDWEST INTO THE GREAT LAKES LATE
SATURDAY WITH AN ADDITIONAL SHORT WAVE PROGGED TO PASS ALONG A
SIMILAR COURSE LATE SUNDAY AND TUESDAY. GUIDANCE FROM BOTH THE GFS
OR EC KEEPS THE FRONT ACROSS OR JUST SOUTH OF CENTRAL NC THROUGH
MUCH OF THE PERIOD. THE LAST FEW RUNS OF THE LARGER SCALE NWP
GUIDANCE HAS TENDED TO KEEP THE SHORTWAVE ENERGY NORTH OF OUR REGION
WHICH WOULD TEND TO FAVOR A SURFACE FRONT THAT IS LESS LIKELY TO
PUSH INTO THE DEEP SOUTH. IN ADDITION...THE LATEST DISCUSSION FROM
WPC CONTINUES TO SUPPORT A LESS PROGRESSIVE PATTERN.
THE RESULT IS A PATTERN THAT WOULD SUPPORT AN UNSETTLED PERIOD BUT
ONE IN WHICH CONFIDENCE ON FORECAST DETAILS...ESPECIALLY LATE IN
LONG TERM IS LOWER THAN TYPICAL. FOR NOW WILL ADVERTISE AN INCREASE
IN THE CHANCE OF SHOWERS AND THUNDERSTORMS LATE THURSDAY AND
ESPECIALLY ON FRIDAY AND SATURDAY WITH THE THUNDERSTORM ACTIVITY
INCREASINGLY CONFINED TO LOCATIONS FURTHER SOUTH THROUGH THE PERIOD
AS COOLER AND MORE STABLE AIR MOVES INTO THE REGION. THE EVENTUAL
FRONTAL POSITION WILL DETERMINE THE DISTRIBUTION OF POPS AND
TEMPERATURES ALTHOUGH A DOWNWARD TREND IN TEMPERATURES IS EXPECTED
THROUGH THE PERIOD WITH TEMPERATURES GENERALLY BECOMING BELOW
AVERAGE BY FRIDAY OR SATURDAY. THE AMOUNT OF CONVECTIVE COVERAGE
OVER THE WEEKEND INTO MONDAY IS STILL UNCERTAIN BUT IN GENERAL THE
CHANCE OF PRECIPITATION WILL GENERALLY DECREASE THROUGH THE PERIOD
AND SHIFT SOUTHEAST WITH TIME. -BLAES
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 135 AM TUESDAY...
IFR CIGS AND MVFR VSBYS ARE LIKELY TO DOMINATE AT ALL TAF SITES
THROUGH NOON. IMPROVEMENT TO MVFR THEN VFR IS EXPECTED AT INT/GSO
FROM 15Z-18Z... AT RDU/FAY 17Z-20Z... AND AT RWI 19Z-22Z. MVFR-IFR
CIGS MAY RETURN AT RDU/RWI AFTER 03Z TONIGHT.
A SURFACE LOW PRESSURE CURRENTLY LOCATED BETWEEN GSB AND FAY WILL
CONTINUE MOVING SLOWLY TOWARD THE NE THIS MORNING... TRACKING ALONG
A FRONTAL ZONE ACROSS OUR SOUTHEAST COUNTIES. SURFACE WINDS FROM THE
N AND NE OVER CENTRAL NC HAVE KEPT A FLOW OF MOIST LOW LEVEL
ATLANTIC AIR ADVECTING INTO THE REGION. WIDESPREAD RAIN AND DRIZZLE
WILL LINGER OVER NORTHEAST SECTIONS IMPACTING RDU/RWI THROUGH
SUNRISE. THIS WILL BE FOLLOWED BY A SLOW TAPERING OFF OF THIS
RAIN/DRIZZLE FROM SW TO NE THROUGH LATE MORNING / EARLY AFTERNOON...
WITH VSBYS REBOUNDING TO VFR ALSO FROM SW TO NE THROUGH THE
AFTERNOON. WEAK HIGH PRESSURE WILL EXTEND OVER THE REGION STARTING
THIS EVENING... RESULTING IN WINDS BECOMING LIGHT... AND WITH THESE
LIGHT WINDS AND A WET GROUND... REDEVELOPMENT OF LOW CLOUDS IS
EXPECTED PRIMARILY AT RDU/RWI TOWARD LATE EVENING.
LOOKING BEYOND 06Z EARLY WED MORNING... SUB-VFR CIGS SHOULD HOLD
MAINLY AT RDU/RWI UNTIL 12Z... THEN THESE CLOUDS WILL MIX OUT WITH
HEATING... AND VFR CONDITIONS ARE EXPECTED AT ALL TAF SITES AFTER
14Z WED... THROUGH THU NIGHT. MVFR-IFR STRATUS IS POSSIBLE LATE THU
NIGHT INTO FRI AS A COLD FRONT APPROACHES FROM THE NW. SUB-VFR
CONDITIONS AND PERIODS OF RAIN ARE EXPECTED TO DOMINATE FRI THROUGH
SAT AS THE FRONT STALLS OVER THE REGION. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BLAES
NEAR TERM...HARTFIELD
SHORT TERM...HARTFIELD
LONG TERM...BLAES
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
147 AM EDT TUE SEP 9 2014
.SYNOPSIS...
DRIER AIR WILL ARRIVE TODAY AS LOW PRESSURE MOVES FURTHER UP THE
MID-ATLANTIC COAST. WARMER TEMPERATURES AND DRY WEATHER ARE EXPECTED
WEDNESDAY AND THURSDAY. A STRONG COLD FRONT WILL ARRIVE LATE WEEK...
DRIFTING SOUTH EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
AS OF 1100 PM MONDAY...UPDATE CONCERNED WITH RE-ALIGNING THE
CURRENT FLOOD WATCH. BASED ON THE LATEST SFC ANALYSIS...THE COLD
FRONT HAS BASICALLY SWEPT ACROSS THE WESTERN 2/3RDS OF THE ILM CWA
AT THE MOMENT. THE SFC LOW CURRENTLY OVER RDU AT THE MOMENT...WITH
THE COLD FRONT EXTENDING SOUTH TO LITTLE RIVER INLET...THEN SW
ALONG THE IMMEDIATE COAST OF SC. WITH THE BEST FORCING/LIFT AND
DEEPEST MOISTURE IE. 2+ PWS...ALONG AND EAST OF THE COLD FRONT.
THIS HAS LEAD TO A RE-STRUCTURE OF THE FLOOD WATCH TO A REDUCTION
TO JUST 3 COUNTIES THAT REMAIN EAST OF THE COLD FRONT...BRUNSWICK
NEW HANOVER AND PENDER. LATEST POPS AND QPF FIELDS HAVE BEEN ALSO
RE-ALIGNED TO ACCOUNT FOR THE NEW FLOOD WATCH CONFIGURATION.
OVERNIGHT MIN TEMPS MAY NEED A TWEAK HERE AND THERE...BUT THE COOL
AND DRIER AIR SURGE BEHIND THE COLD FRONT STILL BASICALLY WELL
UPSTREAM TO AFFECT THE OVERNIGHT PERIOD.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 300 PM MONDAY...LOW PRESSURE WILL BE DEPARTING NORTHEAST TUE
MORNING WITH MID LEVEL DRY AIR MOVING IN FROM THE WEST-NORTHWEST.
THIS SHOULD BRING ABOUT A FAIRLY QUICK END TO ANY LINGER PRECIP TUE
MORNING FOR INLAND SITES. ALONG THE COAST MEASURABLE PRECIP MAY HANG
ON INTO EARLY AFTERNOON WITH LOW LEVEL MOISTURE TRAPPED UNDER MID
LEVEL SUBSIDENCE IN THE WAKE OF THE LOW AND ASSOCIATED WITH THE
SLOWLY EXPANDING SOUTHERN CONUS 5H RIDGE. CLOUD COVER WILL ALSO
LINGER ACROSS THE AREA TUE. GRADUAL CLEARING WILL OCCUR FROM WEST TO
EAST IN THE AFTERNOON BUT THE NC COAST IS LIKELY TO REMAIN CLOUDY
THROUGH SUNSET. TEMPERATURES WILL BE A MIXED BAG WITH INLAND AREAS
RUNNING WARMER DUE TO BREAKS OF SUN LATER IN THE DAY AND SUBTLE
HEIGHT INCREASES. ALONG THE COAST HIGHS WILL BE NEAR TO SLIGHTLY
BELOW CLIMO. CLEARING LATE TUE NIGHT COULD ALLOW FOR A PERIOD OF LOW
STRATUS OR FOG JUST BEFORE DAYBREAK. LATE CLOUD/FOG WILL HELP KEEP
LOWS NEAR CLIMO TUE NIGHT.
MODIFIED HIGH PRESSURE WILL BUILD IN FROM THE WEST ON WED AS MID
LEVEL RIDGE OVER THE SOUTH CONTINUES TO EXPAND EAST. FORECAST
SOUNDINGS SHOW DEEP DRY AIR BUILDING IN...WHICH SHOULD PRODUCE
PARTLY TO MOSTLY SUNNY SKIES. DEEP DRY AIR ALONG WITH WESTERLY FLOW
ALOFT AND LOW LEVEL NORTHEAST FLOW WILL PREVENT DEVELOPMENT OF ANY
MEANINGFUL CONVECTION WED AND PRECIP CHANCES WILL BE NEAR ZERO.
AFOREMENTIONED NORTHEAST FLOW IN THE BOUNDARY LAYER WILL KEEP HIGHS
ALONG THE COAST A LITTLE COOLER...THOUGH STILL ABOVE CLIMO. TEMPS
WED AFTERNOON WILL RANGE FROM LOW 90S INLAND SC TO MID 80S ALONG THE
NC COAST. WEAK WARM ADVECTION DEVELOPS WED NIGHT AS SURFACE RIDGE
AXIS SHIFTS OFFSHORE. SOME MOISTURE RETURN ALONG WITH LIGHT BOUNDARY
LAYER FLOW MAY ALLOW DEVELOPMENT OF FOG LATE IN THE PERIOD. LIGHT
RETURN FLOW AND POTENTIAL FOG WILL KEEP LOWS A LITTLE ABOVE CLIMO.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 300 PM MONDAY...WEAK HIGH PRESSURE WILL REMAIN OVER THE AREA
EARLY THURS AS RIDGE HOLDS ON ALOFT...BUT BY LATE THURS INTO
FRIDAY A COLD FRONT WILL MOVE INTO THE CAROLINAS. SHOULD REMAIN
DRY FOR THURS AT LEAST OVER MOST OF AREA BUT BY THURS NIGHT INTO
FRI...EXPECT INCREASED SHOWER AND THUNDERSTORM ACTIVITY AS FRONT
MOVES THROUGH THE CAROLINAS. PCP WATER VALUES AS LOW AS 1.4 INCHES
THURS MORNING WILL RAMP UP GREATER THAN 2 INCHES JUST AHEAD AND
ALONG COLD FRONT AS IT MOVES SOUTH THROUGH FRI. LOOKS LIKE FRONT
WILL GET HUNG UP OVER THE COAST THROUGH AT LEAST SATURDAY AS
SHORTWAVE LIFTS OFF TO THE NORTHEAST LEAVING A BROAD TROUGH OF LOW
PRESSURE IN THE MID TO UPPER LEVELS. THIS MAINTAINS A SW FLOW
ALOFT RUNNING PARALLEL TO THE FRONT AND MAY KEEP FRONT HUNG UP
OVER OR NEARBY AREA THROUGH MUCH OF THE WEEKEND. A MORE VIGOROUS
SHORTWAVE MAY REACH FAR ENOUGH SOUTH TO GIVE FRONT A PUSH OFF
SHORE BY THE LATTER HALF OF THE WEEKEND. OVERALL EXPECT CLOUDS AND
PCP IN FORECAST FOR MUCH OF FRI AND SATURDAY WITH SOME CLEARING BY
LATE SUNDAY INTO MONDAY AS HIGH PRESSURE BUILDS DOWN FROM THE
NORTH. NOT A HIGH CONFIDENCE FORECAST IN TERMS OF HOW FAR SOUTH
THE FRONT WILL INITIALLY MAKE IT BEFORE STALLING. TOUGH WIND
FORECAST WITH SOUTHERLY WINDS AHEAD OF FRONT THURS INTO FRI BUT
MAY SEE WINDS BECOME VARIABLE OR NORTH AS FRONT REACHES INTO AREA
OVER THE WEEKEND.
EXPECT TEMPS UP AROUND 90 OR SO ON THURS...BUT BY FRI INTO SATURDAY
CLOUDS AND SHWRS WILL AFFECT THE TEMPS AND THEN SOME COOLER AIR WILL
BEGIN TO MOVE IN BEHIND FRONT LATER ON SATURDAY INTO
SUNDAY...KEEPING TEMPS IN THE LOWER 80S OVER THE WEEKEND INTO EARLY
NEXT WEEK. WILL SEE SOME READINGS IN THE 70S FOR HIGHS INLAND WITH
COMBINATION OF COOLER AIR MOVING IN FROM THE N-NW AND CLOUDS AND PCP
OVER THE AREA LATE OVER THE WEEKEND.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 06Z...SHOWER ACTIVITY HAS TRANSITIONED OFFSHORE...AND THE
LATEST HRRR RUNS SUGGEST THE COASTAL SITES WILL SEE MINIMAL IF ANY
PCPN IMPACTS AFTER 06Z. EXPECT MVFR/IFR STRATUS TO PERSIST OVERNIGHT
AS COOLER AIR WRAPS AROUND LOW PRESSURE MOVING ALONG A NEAR
STATIONARY FRONT. BASED ON THE LATEST OBS AND SREF PROBABILITIES...
THE BEST CHANCES FOR IFR CIGS WILL BE INLAND AT KLBT/KFLO. THE
COASTAL TERMINALS MAY ALSO SEE AT LEAST TEMPO IFR CIGS. LIGHT
NORTHWEST WINDS INLAND WILL BECOME MORE NORTHERLY DURING THE DAY.
ALONG THE COAST...WIND DIRECTIONS MAY BECOME VRBL AS THE FRONT
WAVERS NEAR THE AREA. MVFR STRATOCU SHOULD PERSIST THROUGH MUCH OF
THE MORNING. BUT FCST SOUNDINGS DO DEPICT A DRYING TREND BY THE AFTN
HOURS...SO EXPECT CONDITIONS WILL IMPROVE TO VFR FROM SW TO NE AFTER
MIDDAY.
EXTENDED OUTLOOK...VFR WILL PREVAIL WEDNESDAY AND THURSDAY. SHOWERS
AND TSTMS RETURN FRIDAY AND SATURDAY AS ANOTHER COLD FRONT NEARS THE
CAROLINAS.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1115 PM MONDAY...SFC COLD FRONT LOCATED ALONG THE IMMEDIATE
SC COAST AT THE MOMENT...WITH WIND DIRECTIONS AT SW-NW. WILL TAKE
A SURGE OR PUSH FOR THE COLD FRONT ITSELF TO REALLY MAKE SOME
PROGRESS OVER THE COASTAL WATERS. AS A RESULT...WILL HOLD ONTO A
SOLID S-SW 15 KT WIND FROM LITTLE RIVER INLET NORTH...AND SW-WSW
10-15 KT ACROSS THE SC WATERS SOUTH OF LITTLE RIVER INLET. THE SFC
PG ACROSS THE ILM WATERS WILL BE RELAXING AS THE SFC LOW PULLS
FURTHER AWAY TO THE NE OVERNIGHT INTO TUE. THE SIGNIFICANT SEAS AT
2 TO 4 FEET IN THE NEAR TERM WILL REMAIN A FUNCTION OF LOCAL WIND
DRIVEN WAVE PRODUCTION...WITH DOMINANT PERIODS AT 4 TO 6 SECONDS.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 PM MONDAY...EXITING LOW PRESSURE WILL SLOWLY PUSH THE
STALLED FRONT OFF THE COAST DURING TUE. SOUTHWEST FLOW AT THE START
OF THE PERIOD WILL GRADUALLY VEER TO WEST-NORTHWEST LATER TUE AND
TUE NIGHT. GRADIENT REMAINS WEAK AND THE LACK OF ANY COLD PUSH WILL
KEEP WIND SPEEDS 10 KT OR LESS BOTH PRE AND POST FRONT. ELONGATED
SURFACE HIGH BUILDS IN FROM THE WEST WED WITH WINDS VEERING TO
NORTHERLY DURING THE DAY. LATE IN THE DAY SURFACE RIDGE AXIS MOVES
OVERHEAD WITH NORTHERLY FLOW UNDER 10 KT BECOMING LIGHT AND HIGHLY
VARIABLE. WEAK RETURN FLOW DEVELOPS LATE IN THE PERIOD AS THE
SURFACE HIGH SHIFTS EAST OF THE WATERS. SEAS 3 TO 4 FT WILL CARRY
OVER FROM THE PREVIOUS FORECAST PERIOD BUT WILL QUICKLY DROP TO 2 TO
3 FT TUE DUE TO THE COMBINATION OF LIGHT WINDS AND OFFSHORE FLOW.
FURTHER REDUCTION IN SEAS IS ANTICIPATED ON WED.
LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 300 PM MONDAY...SOUTHERLY WINDS WILL INCREASE THROUGH THURS
BETWEEN BERMUDA HIGH AND COLD FRONT MAKING ITS WAY INTO THE
CAROLINAS...BUT OVERALL EXPECT WINDS TO REMAIN BELOW 15 KTS. MUCH
UNCERTAINTY EXISTS AS TO HOW FAR THE FRONT WILL REACH BEFORE
STALLING AND THEREFORE WILL MAINTAIN SOUTHERLY WINDS THROUGH EARLY
SATURDAY. BY LATE SATURDAY INTO SUNDAY WINDS SHOULD COME AROUND TO
THE NE TO N AS FRONT GETS A PUSH SOUTHWARD. WILL SHOW A NORTHERLY
SURGE UP TO 15 KTS BY SUN MORNING BUT THIS IS ALL DEPENDENT ON HOW
FAR SOUTH THE COLD FRONT MAKES IT AND HOW MUCH COLD AIR BLEEDS SOUTH
INTO THE WATERS. SEAS OF 2 TO 3 FT MAY INCREASE UP TO 3 TO 4 FT IN
INCREASED SOUTHERLY FLOW BY SATURDAY AND MAY SEE A BIT MORE OF AN
INCREASE BY SUNDAY IN COOLER NORTHERLY FLOW BEHIND FRONT.
&&
.TIDES/COASTAL FLOODING...
AS OF 1200 AM TUESDAY...TIDE LEVELS MEASURED AT THE CAPE FEAR
RIVER DOWNTOWN GAGE HAVE FALLEN BELOW 5.5 FT MLLW...THRESHOLD FOR
MINOR FLOODING ALONG THE CAPE FEAR RIVER FROM WILMINGTON SOUTH TO
CAPE FEAR. AN UPDATED COASTAL FLOOD ADVISORY HAS BEEN ISSUED
ENDING TONIGHTS THREAT. WITH TOMORROW MORNINGS FORECAST HIGH TIDE
GAGE READING ALONG THE CAPE FEAR A THREAT TO BREAK MINOR COASTAL
FLOOD THRESHOLDS ONCE AGAIN...THE COASTAL FLOOD ADVISORY WILL
REMAIN ACTIVE THROUGH NOON TUESDAY TO KEEP PEOPLE ALERT TO THIS
SUCCESSIVE HIGH TIDE FLOOD THREAT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...FLOOD WATCH UNTIL 8 AM EDT TUESDAY FOR NCZ105>110.
COASTAL FLOOD ADVISORY UNTIL NOON EDT TUESDAY FOR NCZ107.
MARINE...NONE.
&&
$$
NEAR TERM...DCH/TRA
SHORT TERM...III
LONG TERM...RGZ
AVIATION...BJR/RJD
TIDES/COASTAL FLOODING...TRA/DCH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
948 PM CDT WED SEP 10 2014
.UPDATE...
ISSUED AT 947 PM CDT WED SEP 10 2014
TEMPS CONTINUE TO BE THE MAIN QUESTION. MOST LOCATIONS HAVE STAYED
IN THE 40S...ALTHOUGH FOSSTON HAS DROPPED DOWN TO 37 WITH LESS
CLOUD COVER IN THAT AREA AND THAT SITES TYPICAL COLD BIAS. DEW
POINTS EARLIER THIS EVENING WERE IN THE UPPER 20S IN SOME
SPOTS...BUT THERE HAS BEEN AN UPWARD TREND AND CLOUDS CONTINUE TO
INCREASE FROM THE WEST. THERE COULD BE SOME BREAKS IN THE CLOUDS
AND LIGHT ENOUGH WINDS TO DROP A FEW SPOTS INTO THE MID TO LOW
30S. THE DEW POINTS ARE LOWEST IN THE NORTHWESTERN COUNTIES BUT
THE CLOUD COVER IS LESS IN THE NORTHEAST...SO THESE AREAS CONTINUE
TO BE MOST LIKELY TO SEE THE LOW TEMPERATURES. WILL KEEP THE FROST
ADVISORY GOING FOR NOW.
DOWN OVER THE SOUTHWESTERN COUNTIES...RADAR RETURNS HAVE BEEN
ENTERING THE AREA AS A WEAK SHORTWAVE PASSES THROUGH. NOT TOO MUCH
REACHING THE GROUND SO WILL KEEP POPS IN THE 20-30 PERCENT RANGE.
THE PRECIP SHOULD TAPER OFF AFTER MIDNIGHT.
UPDATE ISSUED AT 645 PM CDT WED SEP 10 2014
MADE A FEW MINOR TWEAKS TO POPS AS SHORT RANGE MODELS LIKE THE
HRRR AND THE RAP TREND TOWARDS BRINGING SOME SHOWERS FROM
SOUTHWESTERN ND INTO OUR FAR SOUTHWESTERN COUNTIES. NOT HUGELY
IMPRESSED WITH SIGNIFICANT PRECIP CHANCES...BUT INCLUDED A
ISOLATED MENTION IN THE FAR SOUTHWEST IN CASE SOME SPRINKLES MOVE
INTO RANSOM OR SARGENT COUNTIES. WILL HOLD ONTO FROST HEADLINES
AND CURRENT TEMPS FOR NOW AND TAKE A SECOND LOOK ONCE THE SUN
SETS.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 258 PM CDT WED SEP 10 2014
MAIN FORECAST CHALLENGE WILL BE FROST POTENTIAL THE NEXT FEW
NIGHTS. AS OF MID AFTERNOON SEEING MORE SUN THAN HAD EARLIER
ANTICIPATED. BASICALLY SEEING WEST TO EAST MID LEVEL FLOW WITH
SOME MID LEVEL CLOUDS DRIFTING OVER THE FA. MEANWHILE DRY
NORTHEAST WINDS CONTINUE TO ERODE THE LOWER CLOUDS OVER PORTIONS
OF THE NORTHERN AND EASTERN FA. WINDS ARE STILL PRETTY GUSTY BUT
THESE SHOULD BEGIN TO DECREASE THRU THE EVENING. SHOULD SEE THE
MOST DECREASE IN WINDS LATE...THEREFORE MUCH OF THIS FORECAST
HINGES ON CLOUD COVER. THINK THAT THERE WILL BE SOME CLOUD COVER
OVER THE AREA TONIGHT AND MAYBE MORE SO ACROSS THE SOUTH. WITH
TEMPS ALREADY SO COOL THINK THAT ALL IT WILL TAKE IS AN HOUR OR
SO WITH NO CLOUDS FOR TEMPS TO QUICKLY PLUMMET. THEREFORE DROPPED
LOWS A FEW MORE DEGREES IN THE EAST TO GO ALONG WITH THE EXPECTED
COOLER TEMPS IN THE NORTHWEST. WILL GO WITH A FROST ADVISORY FOR
BOTH AREAS...ESSENTIALLY THE NORTHWEST EDGE OF THE FA AND THE
EASTERN EDGE. IN BETWEEN MAY BE CLOSE AND WILL LET THE EVENING
SHIFT KEEP AN EYE ON THAT. SEEMS LIKE WE TRADITIONALLY MISS THE
FIRST FROST BECAUSE IT IS SO SPOTTY. THIS MAY BE THE CASE THIS
TIME TOO...WITH SOME COLD SPOTS AND FROST WITH SOME WARMER SPOTS
CLOSE BY. WILL CONTINUE TO SEE THE WESTERLY MID LEVEL FLOW ON THU
SO WILL STICK WITH MORE CLOUDS TO THE SOUTH AND LESS NORTH...BUT
AGAIN A TOUGH CALL. MORE OF THE AREA WILL PROBABLY BE UNDER THE
GUN THU NIGHT BUT THINK AREAS ALONG AND NORTH OF HIGHWAY 2 MAY
HAVE THE BEST CHANCE OF FROST.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 258 PM CDT WED SEP 10 2014
SFC HIGH WILL DRIFT SOUTH OF THE AREA FOR FRI INTO SAT. THERE MAY
STILL BE SOME FROST POSSIBLE FRI NIGHT BUT RETURN SOUTH-SW FLOW
WILL DEVELOP. THEREFORE WIND AND CLOUDS WILL REMAIN THE MAIN
CHALLENGE. KEPT A DRY FORECAST SAT ALTHOUGH SEVERAL MODELS SHOW
ANOTHER SFC LOW IN THE NORTHWEST FA WITH A LITTLE LIGHT PCPN
AROUND IT.
LONG TERM MODELS IN SIMILAR AGREEMENT WITH UPPER WAVE EXTENDING
ACROSS S CNTRL CANADA SUN NIGHT...AND POSITION OF SFC HIGH IN MUCH
BETTER AGREEMENT (THAN YESTERDAYS 12Z RUNS) BETWEEN THE GFS/ECMWF.
BOTH MODELS INDICATING MOSTLY DRY WX AS SFC FRONT MOVES ACROSS MB
AND CLIPS THE NORTHERN VALLEY. CONSALL DOES SHOW LOW POPS OVER
NORTHEAST AS BOTH MODELS HAVE PRECIP OVER NE MN SAT NIGHT. SFC HIGH
THEN DOMINATES AREA FOR MON AND TUE OF NEXT WEEK AS DRY AND COOL WX
CONTINUES. RETURN FLOW SETS UP ON TUE...CAUSING A MILD WARMING TREND
BUT DID REMOVE SPOTTY LOW POPS PRODUCED BY CONSALL AS BOTH GFS AND
ECMWF ARE DRY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 645 PM CDT WED SEP 10 2014
VFR CONDITIONS WILL CONTINUE...WITH SOME MID LEVEL CLOUDS AND
CIRRUS IN AND OUT FOR MUCH OF THE NIGHT. WINDS SHOULD LOSE THEIR
GUSTS IN THE NEXT FEW HOURS BUT WILL STILL BE OUT OF THE NORTH AT
10 TO 15 KTS. NORTH TO NORTHWEST WINDS WILL CONTINUE INTO TOMORROW
WITH SOME CIGS OF 4000-6000 FT MOVING INTO THE AREA.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...FROST ADVISORY FROM 4 AM TO 9 AM CDT THURSDAY FOR NDZ006-007-014.
MN...FROST ADVISORY FROM 4 AM TO 9 AM CDT THURSDAY FOR MNZ005-006-008-
009-013>017-023-024.
&&
$$
UPDATE...JR
SHORT TERM...GODON
LONG TERM...GODON/SPEICHER
AVIATION...JR
AREA FORECAST DISCUSSION
NWS BISMARCK ND
912 PM CDT WED SEP 10 2014
.UPDATE...
ISSUED AT 912 PM CDT WED SEP 10 2014
LATEST WATER VAPOR IMAGERY SHOWS A SHORTWAVE ROTATING THROUGH
SOUTHWEST NORTH DAKOTA. UPWARD VERTICAL MOTION ASSOCIATED WITH
THIS SHORTWAVE ALONG WITH THE LEFT EXIT REGION OF AN UPPER JET
ACROSS SOUTHERN NORTH DAKOTA IS PRODUCING SCATTERED RAIN
SHOWERS...WITH AN ISOLATED/BRIEF PERIOD OF SLEET WITHIN THE
STRONGEST VERTICAL MOTION FIELD. THIS WILL CONTINUE TO MOVE INTO
THE JAMES RIVER VALLEY THROUGH THIS LATE EVENING.
OTHERWISE...THE NEXT AREA OF PRECIPITATION WITH FORCING MECHANISMS
VERY SIMILAR TO WHAT WAS MENTIONED ABOVE...IS PROPAGATING THROUGH
SOUTHERN/SOUTHEASTERN MONTANA AT THIS TIME. THE HIGHEST POPS/LIKELY
CATEGORY...WILL JUST GRAZE THE FAR SOUTHWEST PER NAM/RAP OVERNIGHT.
SCATTERED RAIN SHOWERS SEEMS MORE APPROPRIATE...WITH SOME SNOW
POSSIBLY MIXED IN AT TIMES.
DEWPOINTS IN THE TURTLE MOUNTAINS HAVE NOW RISEN INTO THE LOWER
30S. DESPITE SOME CLEARING FROM TIME TO TIME...SATELLITE IMAGERY
AND SURFACE OBS STILL INDICATE ENOUGH CLOUD COVER UPSTREAM TO KEEP
TEMPERATURES ABOVE FREEZING OVERNIGHT. BELIEVE THE FROST ADVISORY
IS IN GOOD STANDING AND WILL NOT MAKE ANY CHANGES AT THIS TIME.
UPDATE ISSUED AT 618 PM CDT WED SEP 10 2014
THE LATEST VISIBLE SATELLITE IMAGERY AND SURFACE OBSERVATIONS SHOW
A CLOUDY SKY ACROSS WESTERN AND CENTRAL NORTH DAKOTA WITH THE
EXCEPTION OF RUGBY AND ROLLA WHERE A STRONGER NORTHEAST FLOW IS
ERODING A CLOUD SHIELD ADVANCING EAST FROM WESTERN NORTH DAKOTA.
THERE ARE MORE HOLES IN THE OVERCAST CONDITIONS ACROSS SOUTHEAST
SASKATCHEWAN AND WESTERN MANITOBA. THE CURRENT FROST ADVISORY AREA
LOOKS ON TRACK AT THIS TIME. WILL MONITOR FOR ADDITIONAL CLEARING
FARTHER WEST AND SEE HOW TEMPERATURES REACT THIS EVENING...GIVEN
DEWPOINTS ARE IN THE UPPER 20S IN THE TURTLE MOUNTAINS. THIS COULD
BECOME A BIGGER CONCERN WITH COLDER LOW TEMPERATURES IF THE SKY
GRID TRENDS CLEARER THAN EXPECTED WITH A CONTINUED NORTHEAST
WIND. HOWEVER AT THIS TIME...FEEL ENOUGH CLOUDS UPSTREAM WILL NEGATE
A POTENTIAL FREEZE WARNING IN THE NORTHEAST...BUT WILL MONITOR
THIS EVENING.
REPORTS OF SOME SNOW MIXED IN WITH THE RAIN AT BEACH LATE THIS
AFTERNOON...ALSO AT NEW ENGLAND AND IN AMIDON. SURFACE TEMPERATURE
ROUGHLY AT 36F FOR THIS MIX TO OCCUR. THIS IS ASSOCIATED WITH A
SHORTWAVE EJECTING OUT OF THE WEST. NORTHEAST WINDS IN CENTRAL
NORTH DAKOTA CONTINUE TO ERODE THE LEADING EDGE OF THIS AREA
SHOWERS. HOWEVER...AN ISOLATED MENTION FROM BISMARCK/MANDAN EAST
INTO THE SOUTHERN JAMES RIVER VALLEY IS WARRANTED PER CURRENT
REFLECTIVITY`S AND HIGH RESOLUTION SOLUTIONS OF THE HRRR AND RAP
WHICH SLIDES A WEAK AREA THROUGH THIS EVENING. MINOR ADJUSTMENTS
TO TEMPERATURES AND DEWPOINTS AS WELL AS POPS THIS EVENING. REST
OF FORECAST REMAINS ON TRACK.
UPDATE ISSUED AT 437 PM CDT WED SEP 10 2014
QUICK UPDATE TO EXPAND AN ISOLATED MENTION OF RAIN SHOWERS THROUGH
SOUTH CENTRAL NORTH DAKOTA THIS EVENING. LATEST BISMARCK AND
BOWMAN RADARS SHOWING AN AREA OF LIGHT RAIN SHOWERS MOVING EAST
OUT OF THE SOUTHWEST. A MID LEVEL CIRCULATION LOCATED IN THE WEST
WILL SLIDE EAST EARLY THIS EVENING...AND CONCUR WITH HIGHER
RESOLUTION MODELS OF THE RAP AND HRRR...THIS PRECIPITATION WEAKENS
BUT ALSO EXPANDS INTO SOUTH CENTRAL NORTH DAKOTA INCLUDING THE SOUTHERN
JAMES RIVER VALLEY BETWEEN 00Z AND 03Z.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 255 PM CDT WED SEP 10 2014
THE MAJOR FORECAST CHALLENGE WILL BE THE FROST POTENTIAL TONIGHT.
THE LATEST SHORT RANGE MODEL GUIDANCE CONTINUES TO PROG BOUNDARY
LAYER MOISTURE TO ERODE TO THE SOUTHWEST AS DRIER AIR GETS USHERED
IN FROM THE NORTHEAST. FURTHERMORE...BOUNDARY LAYER WINDS ARE
FORECAST TO WEAKEN TO AROUND 10 KNOTS TONIGHT AS HIGH PRESSURE
SETTLES INTO MONTANA. HOWEVER...THE LATEST GUIDANCE CONTINUES TO
PROG MID-LEVEL MOISTURE/CLOUDS (USING 850MB-500MB LAYER RH FIELDS)
TO STREAM OVER MOST OF WESTERN AND CENTRAL NORTH DAKOTA TONIGHT
AHEAD OF A SHORTWAVE ROTATING INTO MONTANA. THIS WOULD LIKELY
INHIBIT COOLING TEMPERATURES.
BALANCING WHERE THE CLEARING SKIES ARE FORECAST...WINDS WEAKENING
OVERNIGHT...AND BOUNDARY LAYER TEMPERATURES...THINK THE TURTLE
MOUNTAIN AREA WILL HAVE THE BEST CHANCE OF SEEING A FROST BETWEEN
09Z-14Z THURSDAY MORNING. AS A RESULT...ISSUED A FROST ADVISORY FOR
BOTTINEAU...ROLETTE...AND PIERCE COUNTIES FOR SAID TIME PERIOD.
TO THE SOUTHWEST...THERE WILL BE A CHANCE FOR A RAIN/SNOW MIX AFTER
MIDNIGHT. HOWEVER...ACCUMULATIONS SHOULD BE LIGHT.
FOR THURSDAY...DEEP MOISTURE AND ASSOCIATED PRECIP CHANCES WILL
CONTINUE TO PUSH SOUTH OF THE STATE AS HIGH PRESSURE BUILDS INTO THE
REGION. WELL BELOW NORMAL HIGHS ARE EXPECTED ONCE AGAIN WITH
READINGS RANGING FROM THE MID 40S SOUTHWEST TO THE MID 50S EAST.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 255 PM CDT WED SEP 10 2014
FOCUS IN THE LONG TERM WILL BE ON THE POTENTIAL FOR WIDESPREAD FROST
AND A FREEZE FRIDAY MORNING.
MODEL GUIDANCE CONTINUES TO SHOW LOWS IN THE UPPER 20S ACROSS THE
WEST AND LOWER 30S ELSEWHERE. WITH A LARGE SURFACE HIGH OVER THE
NORTHERN PLAINS WINDS WILL BE LIGHT. THE BIGGEST QUESTION WILL BE
HOW FAST CLOUDS CLEAR OUT. DEEP MOISTURE ACROSS THE STATE WILL BEGIN
TO CLEAR OUT QUICKLY AROUND 18 UTC THURSDAY...HOWEVER THE 12 UTC
MODEL GUIDANCE SHOWS A THIN LAYER OF LOW TO MID LEVEL MOISTURE
HANGING AROUND THROUGH 06 UTC FRIDAY.
REGARDLESS AT LEAST PATCHY FROST SEEMS LIKELY ACROSS CENTRAL AND
WESTERN NORTH DAKOTA. WIDESPREAD FROST IS LOOKING THE MOST LIKELY
ACROSS THE NORTHWEST AS CLOUD COVER WILL CLEAR FROM NORTH TO
SOUTH. THE NORTH WILL ALSO HAVE THE BEST OPPORTUNITY FOR A FREEZE AS
LOWS WILL MOSTLY BE BELOW FREEZING...ESPECIALLY NORTHWEST. AS FOR
THE SOUTH HAVE LIMITED THE WORDING FOR FROST AT AREAS FOR NOW AS
CLOUD COVER MAY STICK AROUND LONG ENOUGH TO PREVENT WIDESPREAD FROST
DEVELOPMENT. FOR THE SAME REASON THERE IS LESS OF A CHANCE OF A
FREEZE ACROSS THE SOUTH. TEMPERATURES WILL ALSO DROP LOW ENOUGH ON
SATURDAY MORNING ACROSS THE SOUTH...ESPECIALLY FOR THE
SOUTHWEST...FOR SOME PATCHY FROST.
FOR THE REMAINDER OF THE LONG TERM THE 12 UTC MODEL GUIDANCE
CONTINUES TO SHOW A MEAN TROUGH OVER THE U.S. THE 12 UTC GFS AND
ECMWF SHOW ANOTHER SHORT WAVE RIDING DOWN THE LEE OF THE CANADIAN
ROCKIES INTO THE NORTHERN PLAINS LATE SATURDAY INTO SUNDAY. MODELS
ARE NOT SHOWING MUCH PRECIPITATION WITH THIS SYSTEM AND THE
REMAINDER OF THE LONG TERM IS ALSO LOOKING MOSTLY DRY AND WARMER.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 618 PM CDT WED SEP 10 2014
MVFR CIGS ARE EXPECTED AT KDIK THROUGH THE TAF PERIOD WITH LOW VFR
CIGS AT THE REMAINING AERODROMES. ISOLATED RAIN SHOWERS WILL
OCCUR AT KBIS THROUGH 04Z THURSDAY. -SHRA ARE FORECAST FOR KDIK
THROUGH THE PERIOD WITH THE POTENTIAL FOR A -SHRASN MIX BETWEEN
09Z AND 15Z THURSDAY. OTHERWISE EXPECT DRY BUT CLOUDY CONDITIONS
ELSEWHERE.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY FROM 4 AM TO 9 AM CDT THURSDAY FOR NDZ004-005-013.
&&
$$
UPDATE...KS
SHORT TERM...TM
LONG TERM...MM
AVIATION...KS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
646 PM CDT WED SEP 10 2014
.UPDATE...
ISSUED AT 645 PM CDT WED SEP 10 2014
MADE A FEW MINOR TWEAKS TO POPS AS SHORT RANGE MODELS LIKE THE
HRRR AND THE RAP TREND TOWARDS BRINGING SOME SHOWERS FROM
SOUTHWESTERN ND INTO OUR FAR SOUTHWESTERN COUNTIES. NOT HUGELY
IMPRESSED WITH SIGNIFICANT PRECIP CHANCES...BUT INCLUDED A
ISOLATED MENTION IN THE FAR SOUTHWEST IN CASE SOME SPRINKLES MOVE
INTO RANSOM OR SARGENT COUNTIES. WILL HOLD ONTO FROST HEADLINES
AND CURRENT TEMPS FOR NOW AND TAKE A SECOND LOOK ONCE THE SUN
SETS.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 258 PM CDT WED SEP 10 2014
MAIN FORECAST CHALLENGE WILL BE FROST POTENTIAL THE NEXT FEW
NIGHTS. AS OF MID AFTERNOON SEEING MORE SUN THAN HAD EARLIER
ANTICIPATED. BASICALLY SEEING WEST TO EAST MID LEVEL FLOW WITH
SOME MID LEVEL CLOUDS DRIFTING OVER THE FA. MEANWHILE DRY
NORTHEAST WINDS CONTINUE TO ERODE THE LOWER CLOUDS OVER PORTIONS
OF THE NORTHERN AND EASTERN FA. WINDS ARE STILL PRETTY GUSTY BUT
THESE SHOULD BEGIN TO DECREASE THRU THE EVENING. SHOULD SEE THE
MOST DECREASE IN WINDS LATE...THEREFORE MUCH OF THIS FORECAST
HINGES ON CLOUD COVER. THINK THAT THERE WILL BE SOME CLOUD COVER
OVER THE AREA TONIGHT AND MAYBE MORE SO ACROSS THE SOUTH. WITH
TEMPS ALREADY SO COOL THINK THAT ALL IT WILL TAKE IS AN HOUR OR
SO WITH NO CLOUDS FOR TEMPS TO QUICKLY PLUMMET. THEREFORE DROPPED
LOWS A FEW MORE DEGREES IN THE EAST TO GO ALONG WITH THE EXPECTED
COOLER TEMPS IN THE NORTHWEST. WILL GO WITH A FROST ADVISORY FOR
BOTH AREAS...ESSENTIALLY THE NORTHWEST EDGE OF THE FA AND THE
EASTERN EDGE. IN BETWEEN MAY BE CLOSE AND WILL LET THE EVENING
SHIFT KEEP AN EYE ON THAT. SEEMS LIKE WE TRADITIONALLY MISS THE
FIRST FROST BECAUSE IT IS SO SPOTTY. THIS MAY BE THE CASE THIS
TIME TOO...WITH SOME COLD SPOTS AND FROST WITH SOME WARMER SPOTS
CLOSE BY. WILL CONTINUE TO SEE THE WESTERLY MID LEVEL FLOW ON THU
SO WILL STICK WITH MORE CLOUDS TO THE SOUTH AND LESS NORTH...BUT
AGAIN A TOUGH CALL. MORE OF THE AREA WILL PROBABLY BE UNDER THE
GUN THU NIGHT BUT THINK AREAS ALONG AND NORTH OF HIGHWAY 2 MAY
HAVE THE BEST CHANCE OF FROST.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 258 PM CDT WED SEP 10 2014
SFC HIGH WILL DRIFT SOUTH OF THE AREA FOR FRI INTO SAT. THERE MAY
STILL BE SOME FROST POSSIBLE FRI NIGHT BUT RETURN SOUTH-SW FLOW
WILL DEVELOP. THEREFORE WIND AND CLOUDS WILL REMAIN THE MAIN
CHALLENGE. KEPT A DRY FORECAST SAT ALTHOUGH SEVERAL MODELS SHOW
ANOTHER SFC LOW IN THE NORTHWEST FA WITH A LITTLE LIGHT PCPN
AROUND IT.
LONG TERM MODELS IN SIMILAR AGREEMENT WITH UPPER WAVE EXTENDING
ACROSS S CNTRL CANADA SUN NIGHT...AND POSITION OF SFC HIGH IN MUCH
BETTER AGREEMENT (THAN YESTERDAYS 12Z RUNS) BETWEEN THE GFS/ECMWF.
BOTH MODELS INDICATING MOSTLY DRY WX AS SFC FRONT MOVES ACROSS MB
AND CLIPS THE NORTHERN VALLEY. CONSALL DOES SHOW LOW POPS OVER
NORTHEAST AS BOTH MODELS HAVE PRECIP OVER NE MN SAT NIGHT. SFC HIGH
THEN DOMINATES AREA FOR MON AND TUE OF NEXT WEEK AS DRY AND COOL WX
CONTINUES. RETURN FLOW SETS UP ON TUE...CAUSING A MILD WARMING TREND
BUT DID REMOVE SPOTTY LOW POPS PRODUCED BY CONSALL AS BOTH GFS AND
ECMWF ARE DRY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 645 PM CDT WED SEP 10 2014
VFR CONDITIONS WILL CONTINUE...WITH SOME MID LEVEL CLOUDS AND
CIRRUS IN AND OUT FOR MUCH OF THE NIGHT. WINDS SHOULD LOSE THEIR
GUSTS IN THE NEXT FEW HOURS BUT WILL STILL BE OUT OF THE NORTH AT
10 TO 15 KTS. NORTH TO NORTHWEST WINDS WILL CONTINUE INTO TOMORROW
WITH SOME CIGS OF 4000-6000 FT MOVING INTO THE AREA.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...FROST ADVISORY FROM 4 AM TO 9 AM CDT THURSDAY FOR NDZ006-007-014.
MN...FROST ADVISORY FROM 4 AM TO 9 AM CDT THURSDAY FOR MNZ005-006-008-
009-013>017-023-024.
&&
$$
UPDATE...JR
SHORT TERM...GODON
LONG TERM...GODON/SPEICHER
AVIATION...JR
AREA FORECAST DISCUSSION
NWS BISMARCK ND
619 PM CDT WED SEP 10 2014
.UPDATE...
ISSUED AT 618 PM CDT WED SEP 10 2014
THE LATEST VISIBLE SATELLITE IMAGERY AND SURFACE OBSERVATIONS SHOW
A CLOUDY SKY ACROSS WESTERN AND CENTRAL NORTH DAKOTA WITH THE
EXCEPTION OF RUGBY AND ROLLA WHERE A STRONGER NORTHEAST FLOW IS
ERODING A CLOUD SHIELD ADVANCING EAST FROM WESTERN NORTH DAKOTA.
THERE ARE MORE HOLES IN THE OVERCAST CONDITIONS ACROSS SOUTHEAST
SASKATCHEWAN AND WESTERN MANITOBA. THE CURRENT FROST ADVISORY AREA
LOOKS ON TRACK AT THIS TIME. WILL MONITOR FOR ADDITIONAL CLEARING
FARTHER WEST AND SEE HOW TEMPERATURES REACT THIS EVENING...GIVEN
DEWPOINTS ARE IN THE UPPER 20S IN THE TURTLE MOUNTAINS. THIS COULD
BECOME A BIGGER CONCERN WITH COLDER LOW TEMPERATURES IF THE SKY
GRID TRENDS CLEARER THAN EXPECTED WITH A CONTINUED NORTHEAST
WIND. HOWEVER AT THIS TIME...FEEL ENOUGH CLOUDS UPSTREAM WILL NEGATE
A POTENTIAL FREEZE WARNING IN THE NORTHEAST...BUT WILL MONITOR
THIS EVENING.
REPORTS OF SOME SNOW MIXED IN WITH THE RAIN AT BEACH LATE THIS
AFTERNOON...ALSO AT NEW ENGLAND AND IN AMIDON. SURFACE TEMPERATURE
ROUGHLY AT 36F FOR THIS MIX TO OCCUR. THIS IS ASSOCIATED WITH A
SHORTWAVE EJECTING OUT OF THE WEST. NORTHEAST WINDS IN CENTRAL
NORTH DAKOTA CONTINUE TO ERODE THE LEADING EDGE OF THIS AREA
SHOWERS. HOWEVER...AN ISOLATED MENTION FROM BISMARCK/MANDAN EAST
INTO THE SOUTHERN JAMES RIVER VALLEY IS WARRANTED PER CURRENT
REFLECTIVITY`S AND HIGH RESOLUTION SOLUTIONS OF THE HRRR AND RAP
WHICH SLIDES A WEAK AREA THROUGH THIS EVENING. MINOR ADJUSTMENTS
TO TEMPERATURES AND DEWPOINTS AS WELL AS POPS THIS EVENING. REST
OF FORECAST REMAINS ON TRACK.
UPDATE ISSUED AT 437 PM CDT WED SEP 10 2014
QUICK UPDATE TO EXPAND AN ISOLATED MENTION OF RAIN SHOWERS THROUGH
SOUTH CENTRAL NORTH DAKOTA THIS EVENING. LATEST BISMARCK AND
BOWMAN RADARS SHOWING AN AREA OF LIGHT RAIN SHOWERS MOVING EAST
OUT OF THE SOUTHWEST. A MID LEVEL CIRCULATION LOCATED IN THE WEST
WILL SLIDE EAST EARLY THIS EVENING...AND CONCUR WITH HIGHER
RESOLUTION MODELS OF THE RAP AND HRRR...THIS PRECIPITATION WEAKENS
BUT ALSO EXPANDS INTO SOUTH CENTRAL NORTH DAKOTA INCLUDING THE SOUTHERN
JAMES RIVER VALLEY BETWEEN 00Z AND 03Z.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 255 PM CDT WED SEP 10 2014
THE MAJOR FORECAST CHALLENGE WILL BE THE FROST POTENTIAL TONIGHT.
THE LATEST SHORT RANGE MODEL GUIDANCE CONTINUES TO PROG BOUNDARY
LAYER MOISTURE TO ERODE TO THE SOUTHWEST AS DRIER AIR GETS USHERED
IN FROM THE NORTHEAST. FURTHERMORE...BOUNDARY LAYER WINDS ARE
FORECAST TO WEAKEN TO AROUND 10 KNOTS TONIGHT AS HIGH PRESSURE
SETTLES INTO MONTANA. HOWEVER...THE LATEST GUIDANCE CONTINUES TO
PROG MID-LEVEL MOISTURE/CLOUDS (USING 850MB-500MB LAYER RH FIELDS)
TO STREAM OVER MOST OF WESTERN AND CENTRAL NORTH DAKOTA TONIGHT
AHEAD OF A SHORTWAVE ROTATING INTO MONTANA. THIS WOULD LIKELY
INHIBIT COOLING TEMPERATURES.
BALANCING WHERE THE CLEARING SKIES ARE FORECAST...WINDS WEAKENING
OVERNIGHT...AND BOUNDARY LAYER TEMPERATURES...THINK THE TURTLE
MOUNTAIN AREA WILL HAVE THE BEST CHANCE OF SEEING A FROST BETWEEN
09Z-14Z THURSDAY MORNING. AS A RESULT...ISSUED A FROST ADVISORY FOR
BOTTINEAU...ROLETTE...AND PIERCE COUNTIES FOR SAID TIME PERIOD.
TO THE SOUTHWEST...THERE WILL BE A CHANCE FOR A RAIN/SNOW MIX AFTER
MIDNIGHT. HOWEVER...ACCUMULATIONS SHOULD BE LIGHT.
FOR THURSDAY...DEEP MOISTURE AND ASSOCIATED PRECIP CHANCES WILL
CONTINUE TO PUSH SOUTH OF THE STATE AS HIGH PRESSURE BUILDS INTO THE
REGION. WELL BELOW NORMAL HIGHS ARE EXPECTED ONCE AGAIN WITH
READINGS RANGING FROM THE MID 40S SOUTHWEST TO THE MID 50S EAST.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 255 PM CDT WED SEP 10 2014
FOCUS IN THE LONG TERM WILL BE ON THE POTENTIAL FOR WIDESPREAD FROST
AND A FREEZE FRIDAY MORNING.
MODEL GUIDANCE CONTINUES TO SHOW LOWS IN THE UPPER 20S ACROSS THE
WEST AND LOWER 30S ELSEWHERE. WITH A LARGE SURFACE HIGH OVER THE
NORTHERN PLAINS WINDS WILL BE LIGHT. THE BIGGEST QUESTION WILL BE
HOW FAST CLOUDS CLEAR OUT. DEEP MOISTURE ACROSS THE STATE WILL BEGIN
TO CLEAR OUT QUICKLY AROUND 18 UTC THURSDAY...HOWEVER THE 12 UTC
MODEL GUIDANCE SHOWS A THIN LAYER OF LOW TO MID LEVEL MOISTURE
HANGING AROUND THROUGH 06 UTC FRIDAY.
REGARDLESS AT LEAST PATCHY FROST SEEMS LIKELY ACROSS CENTRAL AND
WESTERN NORTH DAKOTA. WIDESPREAD FROST IS LOOKING THE MOST LIKELY
ACROSS THE NORTHWEST AS CLOUD COVER WILL CLEAR FROM NORTH TO
SOUTH. THE NORTH WILL ALSO HAVE THE BEST OPPORTUNITY FOR A FREEZE AS
LOWS WILL MOSTLY BE BELOW FREEZING...ESPECIALLY NORTHWEST. AS FOR
THE SOUTH HAVE LIMITED THE WORDING FOR FROST AT AREAS FOR NOW AS
CLOUD COVER MAY STICK AROUND LONG ENOUGH TO PREVENT WIDESPREAD FROST
DEVELOPMENT. FOR THE SAME REASON THERE IS LESS OF A CHANCE OF A
FREEZE ACROSS THE SOUTH. TEMPERATURES WILL ALSO DROP LOW ENOUGH ON
SATURDAY MORNING ACROSS THE SOUTH...ESPECIALLY FOR THE
SOUTHWEST...FOR SOME PATCHY FROST.
FOR THE REMAINDER OF THE LONG TERM THE 12 UTC MODEL GUIDANCE
CONTINUES TO SHOW A MEAN TROUGH OVER THE U.S. THE 12 UTC GFS AND
ECMWF SHOW ANOTHER SHORT WAVE RIDING DOWN THE LEE OF THE CANADIAN
ROCKIES INTO THE NORTHERN PLAINS LATE SATURDAY INTO SUNDAY. MODELS
ARE NOT SHOWING MUCH PRECIPITATION WITH THIS SYSTEM AND THE
REMAINDER OF THE LONG TERM IS ALSO LOOKING MOSTLY DRY AND WARMER.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 618 PM CDT WED SEP 10 2014
MVFR CIGS ARE EXPECTED AT KDIK THROUGH THE TAF PERIOD WITH LOW VFR
CIGS AT THE REMAINING AERODROMES. ISOLATED RAIN SHOWERS WILL
OCCUR AT KBIS THROUGH 04Z THURSDAY. -SHRA ARE FORECAST FOR KDIK
THROUGH THE PERIOD WITH THE POTENTIAL FOR A -SHRASN MIX BETWEEN
09Z AND 15Z THURSDAY. OTHERWISE EXPECT DRY BUT CLOUDY CONDITIONS
ELSEWHERE.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY FROM 4 AM TO 9 AM CDT THURSDAY FOR NDZ004-005-013.
&&
$$
UPDATE...KS
SHORT TERM...TM
LONG TERM...MM
AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1155 AM CDT TUE SEP 9 2014
.UPDATE...
ISSUED AT 1155 AM CDT TUE SEP 9 2014
REMOVED THUNDERSTORM WORDING FROM THE MORNING FORECAST AS
CONVECTIVE ACTIVITY HAS MELLOWED IN THE PAST FEW HOURS. THE NEXT
FORECAST CHALLENGE WILL BE DETERMINING IF ANY FROST HEADLINES WILL
BE NEEDED TONIGHT. OTHERWISE...THE UPDATED FIRST-PERIOD PRODUCTS
HAVE BEEN SENT.
UPDATE ISSUED AT 957 AM CDT TUE SEP 9 2014
MAINTAINED THE SLIGHT CHANCE OF THUNDERSTORM WORDING THIS MORNING
AS SOME ACTIVITY IN THE AREA HAS PRODUCED A LIGHTNING STRIKE OR
TWO IN THE LAST FEW HOURS. MAINLY A CHANCE OF RAIN SHOWERS IS
FORECAST FOR THIS AFTERNOON.
FOCUS THEN SHIFTS TO THE FROST POTENTIAL TONIGHT. THICK CLOUD
COVER COMBINED WITH TURBULENT BOUNDARY LAYER FLOW SHOULD INHIBIT
TEMPERATURES FROM COOLING MUCH OVERNIGHT. HOWEVER...NEAR-SURFACE
COLD AIR ADVECTION COULD OVERCOME THE CLOUDS/WINDS AND ALLOW
TEMPERATURES TO FALL IN THE MID TO UPPER 30S...MAINLY OVER WESTERN
NORTH DAKOTA PROXIMATE TO THE CENTER OF COLD CANADIAN AIR MASS
CENTERED OVER ALBERTA. SHOULD BE ABLE TO DECIDE ON WHETHER FROST
HEADLINES WILL BE NEEDED FOR TONIGHT AFTER THE LATEST MODEL SUITE
BECOMES AVAILABLE.
UPDATE ISSUED AT 639 AM CDT TUE SEP 9 2014
A FEW LIGHTNING STRIKES HAVE BEEN NOTED EARLIER THIS MORNING ACROSS
SOUTHWEST NORTH DAKOTA...AND RECENTLY OVER NORTHWEST NORTH DAKOTA.
LATEST 10 UTC RAP BUFKIT SOUNDINGS DO SHOW SOME SOME SLIGHT
ELEVATED CAPE ACROSS THE FORECAST AREA THIS MORNING. THUS WILL
MENTION A SLIGHT CHANCE OF THUNDER. OTHERWISE NO SIGNIFICANT
CHANGES TO THE GOING FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 315 AM CDT TUE SEP 9 2014
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE MUCH COLDER
TEMPERATURES TODAY COMPARED TO MONDAY...WITH CHANCES FOR
PRECIPITATION THROUGH THE PERIOD WITH A POSSIBLE RAIN/SNOW MIX AND
AREAS OF FROST LATE TONIGHT WEST AND NORTH CENTRAL.
CURRENTLY...ARCTIC COLD FRONT TO OUR SOUTH THIS MORNING WITH CAA
STRATUS ACROSS ALL OF NORTH DAKOTA. LOW PRESSURE CENTERED OVER THE
BLACK HILLS OF WESTERN SOUTH DAKOTA...WITH OVERRUNNING FLOW
TRIGGERING SCATTERED SHOWERS ALONG TO SOUTH OF THE INTERSTATE.
ENOUGH INSTABILITY FOR A FEW LIGHTNING STRIKES THROUGH 12Z.
BROAD MID LEVEL TROUGH WILL LINGER OVER THE REGION TODAY AND
TONIGHT. WILL MAINTAIN SOME MENTION OF LIGHT RAIN MOST LOCATIONS.
WILL SEE BEST CHANCES FOR RAINFALL ACROSS THE JAMES RIVER VALLEY
AS MID LEVEL ENERGY INTERACTS WITH A FRONTAL BOUNDARY. MODELS ARE
ALSO FAVORING THE NORTHWEST NEAR UPPER JET INDUCED FORCING.
WILL MAINTAIN A SLIGHT CHANCE MENTION OF SNOW NORTHWEST OVERNIGHT
TONIGHT WHEN CAA BRINGS THE BEST CHANCE FOR A CHANGE IN
PRECIPITATION PHASE. SOUTH AND EAST OF THIS AREA SHOULD REMAIN
MAINLY RAIN.
LINGERING CLOUD COVER LEADS TO SOME UNCERTAINTY IN REGARDS TO
OVERNIGHT LOWS. WHILE I KEPT FROST IN THE FORECAST WEST AND NORTH
CENTRAL...WILL HOLD ON ISSUING ANY HEADLINES WITH THIS FORECAST
ISSUANCE AND LET THE DAY SHIFT DIGEST HOPEFULLY NEWER AND BETTER
MODEL DATA. IT DOES APPEAR THE NORTH CENTRAL HAS THE BEST POTENTIAL
TO CLEAR LATER TONIGHT ALLOWING TEMPERATURES TO PLUMMET.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 335 AM CDT TUE SEP 9 2014
THE MAIN FORECAST ISSUE IN THE LONG TERM PERIOD WILL BE FROST/FREEZE
POSSIBILITIES...AND PRECIPITATION CHANCES/TYPES WEDNESDAY NIGHT INTO
THURSDAY MORNING. THEN FROST/FREEZE POSSIBILITIES AGAIN THURSDAY
NIGHT INTO FRIDAY MORNING.
WE BEGIN THE LONG TERM PERIOD WEDNESDAY MORNING WITH A BROAD UPPER
TROUGH OVER THE NORTHERN U.S. AND A SHORTWAVE TROUGH DROPPING DOWN
THE LEE OF THE CANADIAN ROCKIES INTO THE MEAN LONGWAVE TROUGH. THE
FORCING ASSOCIATED WITH A SURFACE SYSTEM WILL BE EXITING THE
SOUTHEAST CWA...WHILE THE FORCING AHEAD OF THE NORTHERN STREAM WAVE
IS EXPECTED TO RESULT IN LIGHT RAIN TUESDAY NIGHT INTO WEDNESDAY
MORNING OVER MAINLY THE WESTERN THIRD OF THE FORECAST AREA. HAVE
KEPT A MENTION OF A RAIN SNOW MIX FOR A BRIEF PERIOD WEDNESDAY
MORNING OVER THE NORTHWEST...WITH AREAS OF FROST IN THE WEST AND
NORTH CENTRAL.
ON WEDNESDAY NIGHT INTO THURSDAY MORNING...THE NORTHERN STREAM WAVE
DROPS INTO THE NORTHERN PLAINS. THE ECMWF IS THE DEEPEST WITH THIS
SYSTEM AND EVEN DEVELOPS A CLOSED UPPER LOW OVER SOUTHWEST NORTH
DAKOTA LATE THURSDAY. THIS RESULTS IN A MUCH WETTER SOLUTION THAN
THE REMAINING DETERMINISTIC MODELS OVER WESTERN AND CENTRAL NORTH
DAKOTA. MOST MODELS KEEP THE CWA DRY EXCEPT FOR POSSIBLY THE FAR
SOUTHWEST THURSDAY MORNING. HAVE UTILIZED A BLEND HERE...KEEPING AT
LEAST A SLIGHT CHANCE OF PRECIPITATION ACROSS MUCH OF THE WEST AND
CENTRAL. BUT KEEPING ONLY CHANCE POPS OVER THE SOUTHWEST LATE
WEDNESDAY NIGHT AND THURSDAY MORNING. ANOTHER BIG PROBLEM WILL BE
WHERE TO MENTION FROST. IF THE ECMWF IS CORRECT...THERE SHOULD BE
MUCH MORE CLOUD COVER...LIMITING THE POTENTIAL FOR FROST.
HOWEVER...THE ALTERNATIVE SOLUTION WILL LIKELY RESULT IN MORE
WIDESPREAD FROST. WITH SUCH UNCERTAINTY WE WILL NOT ISSUE ANY FROST
HIGHLIGHTS THIS MORNING BUT WILL CONTINUE THE SPS ISSUED PREVIOUSLY.
THURSDAY NIGHT INTO FRIDAY MORNING IS SHAPING UP TO BE ANOTHER COLD
MORNING...WITH THE POSSIBILITY OF FREEZING TEMPERATURES ACROSS A
GOOD PORTION OF THE WEST AND NORTH. WE WILL NEED TO MONITOR FOR
POSSIBLE FREEZE HEADLINES...BUT WOULD NOT ISSUE ANYTHING THIS FAR
OUT. THUS WILL CONTINUE A MENTION OF FROST IN THE GRIDDED FORECAST
WITH HAZARDS MENTIONED IN THE HAZARDOUS WEATHER OUTLOOK.
BEYOND FRIDAY...IT LOOKS DRY WITH TEMPERATURES MODERATING THROUGH
THE WEEKEND...WITH TEMPERATURES BACK TO NEAR NORMAL BY THE FIRST OF
NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1155 AM CDT TUE SEP 9 2014
MVFR CONDITIONS WILL PREVAIL OVER KISN-KMOT-KBIS-KJMS THROUGH THE
LATE EVENING HOURS. IFR/LIFR CONDITIONS WILL PERSIST OVER KDIK
THROUGH THE EVENING HOURS. DRIER AIR WILL GRADUALLY BUILD IN FROM
NORTHEAST TO SOUTHWEST AFTER MIDNIGHT THROUGH THE REMAINDER OF THE
TAF PERIOD. SEE INDIVIDUAL TAFS FOR TIMING DETAILS WITH REGARDS
TO FLIGHT RULES IMPROVING TO VFR WEDNESDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TM
SHORT TERM...NH
LONG TERM...TWH
AVIATION...TM
AREA FORECAST DISCUSSION
NWS BISMARCK ND
957 AM CDT TUE SEP 9 2014
.UPDATE...
ISSUED AT 957 AM CDT TUE SEP 9 2014
MAINTAINED THE SLIGHT CHANCE OF THUNDERSTORM WORDING THIS MORNING
AS SOME ACTIVITY IN THE AREA HAS PRODUCED A LIGHTNING STRIKE OR
TWO IN THE LAST FEW HOURS. MAINLY A CHANCE OF RAIN SHOWERS IS
FORECAST FOR THIS AFTERNOON.
FOCUS THEN SHIFTS TO THE FROST POTENTIAL TONIGHT. THICK CLOUD
COVER COMBINED WITH TURBULENT BOUNDARY LAYER FLOW SHOULD INHIBIT
TEMPERATURES FROM COOLING MUCH OVERNIGHT. HOWEVER...NEAR-SURFACE
COLD AIR ADVECTION COULD OVERCOME THE CLOUDS/WINDS AND ALLOW
TEMPERATURES TO FALL IN THE MID TO UPPER 30S...MAINLY OVER WESTERN
NORTH DAKOTA PROXIMATE TO THE CENTER OF COLD CANADIAN AIR MASS
CENTERED OVER ALBERTA. SHOULD BE ABLE TO DECIDE ON WHETHER FROST
HEADLINES WILL BE NEEDED FOR TONIGHT AFTER THE LATEST MODEL SUITE
BECOMES AVAILABLE.
UPDATE ISSUED AT 639 AM CDT TUE SEP 9 2014
A FEW LIGHTNING STRIKES HAVE BEEN NOTED EARLIER THIS MORNING ACROSS
SOUTHWEST NORTH DAKOTA...AND RECENTLY OVER NORTHWEST NORTH DAKOTA.
LATEST 10 UTC RAP BUFKIT SOUNDINGS DO SHOW SOME SOME SLIGHT
ELEVATED CAPE ACROSS THE FORECAST AREA THIS MORNING. THUS WILL
MENTION A SLIGHT CHANCE OF THUNDER. OTHERWISE NO SIGNIFICANT
CHANGES TO THE GOING FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 315 AM CDT TUE SEP 9 2014
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE MUCH COLDER
TEMPERATURES TODAY COMPARED TO MONDAY...WITH CHANCES FOR
PRECIPITATION THROUGH THE PERIOD WITH A POSSIBLE RAIN/SNOW MIX AND
AREAS OF FROST LATE TONIGHT WEST AND NORTH CENTRAL.
CURRENTLY...ARCTIC COLD FRONT TO OUR SOUTH THIS MORNING WITH CAA
STRATUS ACROSS ALL OF NORTH DAKOTA. LOW PRESSURE CENTERED OVER THE
BLACK HILLS OF WESTERN SOUTH DAKOTA...WITH OVERRUNNING FLOW
TRIGGERING SCATTERED SHOWERS ALONG TO SOUTH OF THE INTERSTATE.
ENOUGH INSTABILITY FOR A FEW LIGHTNING STRIKES THROUGH 12Z.
BROAD MID LEVEL TROUGH WILL LINGER OVER THE REGION TODAY AND
TONIGHT. WILL MAINTAIN SOME MENTION OF LIGHT RAIN MOST LOCATIONS.
WILL SEE BEST CHANCES FOR RAINFALL ACROSS THE JAMES RIVER VALLEY
AS MID LEVEL ENERGY INTERACTS WITH A FRONTAL BOUNDARY. MODELS ARE
ALSO FAVORING THE NORTHWEST NEAR UPPER JET INDUCED FORCING.
WILL MAINTAIN A SLIGHT CHANCE MENTION OF SNOW NORTHWEST OVERNIGHT
TONIGHT WHEN CAA BRINGS THE BEST CHANCE FOR A CHANGE IN
PRECIPITATION PHASE. SOUTH AND EAST OF THIS AREA SHOULD REMAIN
MAINLY RAIN.
LINGERING CLOUD COVER LEADS TO SOME UNCERTAINTY IN REGARDS TO
OVERNIGHT LOWS. WHILE I KEPT FROST IN THE FORECAST WEST AND NORTH
CENTRAL...WILL HOLD ON ISSUING ANY HEADLINES WITH THIS FORECAST
ISSUANCE AND LET THE DAY SHIFT DIGEST HOPEFULLY NEWER AND BETTER
MODEL DATA. IT DOES APPEAR THE NORTH CENTRAL HAS THE BEST POTENTIAL
TO CLEAR LATER TONIGHT ALLOWING TEMPERATURES TO PLUMMET.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 335 AM CDT TUE SEP 9 2014
THE MAIN FORECAST ISSUE IN THE LONG TERM PERIOD WILL BE FROST/FREEZE
POSSIBILITIES...AND PRECIPITATION CHANCES/TYPES WEDNESDAY NIGHT INTO
THURSDAY MORNING. THEN FROST/FREEZE POSSIBILITIES AGAIN THURSDAY
NIGHT INTO FRIDAY MORNING.
WE BEGIN THE LONG TERM PERIOD WEDNESDAY MORNING WITH A BROAD UPPER
TROUGH OVER THE NORTHERN U.S. AND A SHORTWAVE TROUGH DROPPING DOWN
THE LEE OF THE CANADIAN ROCKIES INTO THE MEAN LONGWAVE TROUGH. THE
FORCING ASSOCIATED WITH A SURFACE SYSTEM WILL BE EXITING THE
SOUTHEAST CWA...WHILE THE FORCING AHEAD OF THE NORTHERN STREAM WAVE
IS EXPECTED TO RESULT IN LIGHT RAIN TUESDAY NIGHT INTO WEDNESDAY
MORNING OVER MAINLY THE WESTERN THIRD OF THE FORECAST AREA. HAVE
KEPT A MENTION OF A RAIN SNOW MIX FOR A BRIEF PERIOD WEDNESDAY
MORNING OVER THE NORTHWEST...WITH AREAS OF FROST IN THE WEST AND
NORTH CENTRAL.
ON WEDNESDAY NIGHT INTO THURSDAY MORNING...THE NORTHERN STREAM WAVE
DROPS INTO THE NORTHERN PLAINS. THE ECMWF IS THE DEEPEST WITH THIS
SYSTEM AND EVEN DEVELOPS A CLOSED UPPER LOW OVER SOUTHWEST NORTH
DAKOTA LATE THURSDAY. THIS RESULTS IN A MUCH WETTER SOLUTION THAN
THE REMAINING DETERMINISTIC MODELS OVER WESTERN AND CENTRAL NORTH
DAKOTA. MOST MODELS KEEP THE CWA DRY EXCEPT FOR POSSIBLY THE FAR
SOUTHWEST THURSDAY MORNING. HAVE UTILIZED A BLEND HERE...KEEPING AT
LEAST A SLIGHT CHANCE OF PRECIPITATION ACROSS MUCH OF THE WEST AND
CENTRAL. BUT KEEPING ONLY CHANCE POPS OVER THE SOUTHWEST LATE
WEDNESDAY NIGHT AND THURSDAY MORNING. ANOTHER BIG PROBLEM WILL BE
WHERE TO MENTION FROST. IF THE ECMWF IS CORRECT...THERE SHOULD BE
MUCH MORE CLOUD COVER...LIMITING THE POTENTIAL FOR FROST.
HOWEVER...THE ALTERNATIVE SOLUTION WILL LIKELY RESULT IN MORE
WIDESPREAD FROST. WITH SUCH UNCERTAINTY WE WILL NOT ISSUE ANY FROST
HIGHLIGHTS THIS MORNING BUT WILL CONTINUE THE SPS ISSUED PREVIOUSLY.
THURSDAY NIGHT INTO FRIDAY MORNING IS SHAPING UP TO BE ANOTHER COLD
MORNING...WITH THE POSSIBILITY OF FREEZING TEMPERATURES ACROSS A
GOOD PORTION OF THE WEST AND NORTH. WE WILL NEED TO MONITOR FOR
POSSIBLE FREEZE HEADLINES...BUT WOULD NOT ISSUE ANYTHING THIS FAR
OUT. THUS WILL CONTINUE A MENTION OF FROST IN THE GRIDDED FORECAST
WITH HAZARDS MENTIONED IN THE HAZARDOUS WEATHER OUTLOOK.
BEYOND FRIDAY...IT LOOKS DRY WITH TEMPERATURES MODERATING THROUGH
THE WEEKEND...WITH TEMPERATURES BACK TO NEAR NORMAL BY THE FIRST OF
NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 639 AM CDT TUE SEP 9 2014
MVFR-IFR STRATUS AT ALL TERMINALS WILL PERSIST THROUGH MUCH OF THE
MORNING. MODELS DO HINT AT CIGS LIFTING TO MVFR-LOW VFR FROM THE
MID MORNING HOURS INTO THE EARLY AFTERNOON...16-20Z. A FEW POCKETS
OF LIFR NORTHWEST AND SOUTH...POSSIBLY IMPACTING KISN-KBIS AND
ESPECIALLY KDIK NOW THROUGH 15-17Z. INSTABILITY ALOFT HAS RESULTED
IN ISOLATED LIGHTNING STRIKES THIS MORNING...BUT TOO SPARSE TO ADD
A VCTS TO ANY SINGLE AERODROME AT THIS TIME.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TM
SHORT TERM...NH
LONG TERM...TWH
AVIATION...NH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
639 AM CDT TUE SEP 9 2014
.UPDATE...
ISSUED AT 639 AM CDT TUE SEP 9 2014
A FEW LIGHTNING STRIKES HAVE BEEN NOTED EARLIER THIS MORNING ACROSS
SOUTHWEST NORTH DAKOTA...AND RECENTLY OVER NORTHWEST NORTH DAKOTA.
LATEST 10 UTC RAP BUFKIT SOUNDINGS DO SHOW SOME SOME SLIGHT
ELEVATED CAPE ACROSS THE FORECAST AREA THIS MORNING. THUS WILL
MENTION A SLIGHT CHANCE OF THUNDER. OTHERWISE NO SIGNIFICANT
CHANGES TO THE GOING FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 315 AM CDT TUE SEP 9 2014
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE MUCH COLDER
TEMPERATURES TODAY COMPARED TO MONDAY...WITH CHANCES FOR
PRECIPITATION THROUGH THE PERIOD WITH A POSSIBLE RAIN/SNOW MIX AND
AREAS OF FROST LATE TONIGHT WEST AND NORTH CENTRAL.
CURRENTLY...ARCTIC COLD FRONT TO OUR SOUTH THIS MORNING WITH CAA
STRATUS ACROSS ALL OF NORTH DAKOTA. LOW PRESSURE CENTERED OVER THE
BLACK HILLS OF WESTERN SOUTH DAKOTA...WITH OVERRUNNING FLOW
TRIGGERING SCATTERED SHOWERS ALONG TO SOUTH OF THE INTERSTATE.
ENOUGH INSTABILITY FOR A FEW LIGHTNING STRIKES THROUGH 12Z.
BROAD MID LEVEL TROUGH WILL LINGER OVER THE REGION TODAY AND
TONIGHT. WILL MAINTAIN SOME MENTION OF LIGHT RAIN MOST LOCATIONS.
WILL SEE BEST CHANCES FOR RAINFALL ACROSS THE JAMES RIVER VALLEY
AS MID LEVEL ENERGY INTERACTS WITH A FRONTAL BOUNDARY. MODELS ARE
ALSO FAVORING THE NORTHWEST NEAR UPPER JET INDUCED FORCING.
WILL MAINTAIN A SLIGHT CHANCE MENTION OF SNOW NORTHWEST OVERNIGHT
TONIGHT WHEN CAA BRINGS THE BEST CHANCE FOR A CHANGE IN
PRECIPITATION PHASE. SOUTH AND EAST OF THIS AREA SHOULD REMAIN
MAINLY RAIN.
LINGERING CLOUD COVER LEADS TO SOME UNCERTAINTY IN REGARDS TO
OVERNIGHT LOWS. WHILE I KEPT FROST IN THE FORECAST WEST AND NORTH
CENTRAL...WILL HOLD ON ISSUING ANY HEADLINES WITH THIS FORECAST
ISSUANCE AND LET THE DAY SHIFT DIGEST HOPEFULLY NEWER AND BETTER
MODEL DATA. IT DOES APPEAR THE NORTH CENTRAL HAS THE BEST POTENTIAL
TO CLEAR LATER TONIGHT ALLOWING TEMPERATURES TO PLUMMET.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 335 AM CDT TUE SEP 9 2014
THE MAIN FORECAST ISSUE IN THE LONG TERM PERIOD WILL BE FROST/FREEZE
POSSIBILITIES...AND PRECIPITATION CHANCES/TYPES WEDNESDAY NIGHT INTO
THURSDAY MORNING. THEN FROST/FREEZE POSSIBILITIES AGAIN THURSDAY
NIGHT INTO FRIDAY MORNING.
WE BEGIN THE LONG TERM PERIOD WEDNESDAY MORNING WITH A BROAD UPPER
TROUGH OVER THE NORTHERN U.S. AND A SHORTWAVE TROUGH DROPPING DOWN
THE LEE OF THE CANADIAN ROCKIES INTO THE MEAN LONGWAVE TROUGH. THE
FORCING ASSOCIATED WITH A SURFACE SYSTEM WILL BE EXITING THE
SOUTHEAST CWA...WHILE THE FORCING AHEAD OF THE NORTHERN STREAM WAVE
IS EXPECTED TO RESULT IN LIGHT RAIN TUESDAY NIGHT INTO WEDNESDAY
MORNING OVER MAINLY THE WESTERN THIRD OF THE FORECAST AREA. HAVE
KEPT A MENTION OF A RAIN SNOW MIX FOR A BRIEF PERIOD WEDNESDAY
MORNING OVER THE NORTHWEST...WITH AREAS OF FROST IN THE WEST AND
NORTH CENTRAL.
ON WEDNESDAY NIGHT INTO THURSDAY MORNING...THE NORTHERN STREAM WAVE
DROPS INTO THE NORTHERN PLAINS. THE ECMWF IS THE DEEPEST WITH THIS
SYSTEM AND EVEN DEVELOPS A CLOSED UPPER LOW OVER SOUTHWEST NORTH
DAKOTA LATE THURSDAY. THIS RESULTS IN A MUCH WETTER SOLUTION THAN
THE REMAINING DETERMINISTIC MODELS OVER WESTERN AND CENTRAL NORTH
DAKOTA. MOST MODELS KEEP THE CWA DRY EXCEPT FOR POSSIBLY THE FAR
SOUTHWEST THURSDAY MORNING. HAVE UTILIZED A BLEND HERE...KEEPING AT
LEAST A SLIGHT CHANCE OF PRECIPITATION ACROSS MUCH OF THE WEST AND
CENTRAL. BUT KEEPING ONLY CHANCE POPS OVER THE SOUTHWEST LATE
WEDNESDAY NIGHT AND THURSDAY MORNING. ANOTHER BIG PROBLEM WILL BE
WHERE TO MENTION FROST. IF THE ECMWF IS CORRECT...THERE SHOULD BE
MUCH MORE CLOUD COVER...LIMITING THE POTENTIAL FOR FROST.
HOWEVER...THE ALTERNATIVE SOLUTION WILL LIKELY RESULT IN MORE
WIDESPREAD FROST. WITH SUCH UNCERTAINTY WE WILL NOT ISSUE ANY FROST
HIGHLIGHTS THIS MORNING BUT WILL CONTINUE THE SPS ISSUED PREVIOUSLY.
THURSDAY NIGHT INTO FRIDAY MORNING IS SHAPING UP TO BE ANOTHER COLD
MORNING...WITH THE POSSIBILITY OF FREEZING TEMPERATURES ACROSS A
GOOD PORTION OF THE WEST AND NORTH. WE WILL NEED TO MONITOR FOR
POSSIBLE FREEZE HEADLINES...BUT WOULD NOT ISSUE ANYTHING THIS FAR
OUT. THUS WILL CONTINUE A MENTION OF FROST IN THE GRIDDED FORECAST
WITH HAZARDS MENTIONED IN THE HAZARDOUS WEATHER OUTLOOK.
BEYOND FRIDAY...IT LOOKS DRY WITH TEMPERATURES MODERATING THROUGH
THE WEEKEND...WITH TEMPERATURES BACK TO NEAR NORMAL BY THE FIRST OF
NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 639 AM CDT TUE SEP 9 2014
MVFR-IFR STRATUS AT ALL TERMINALS WILL PERSIST THROUGH MUCH OF THE
MORNING. MODELS DO HINT AT CIGS LIFTING TO MVFR-LOW VFR FROM THE
MID MORNING HOURS INTO THE EARLY AFTERNOON...16-20Z. A FEW POCKETS
OF LIFR NORTHWEST AND SOUTH...POSSIBLY IMPACTING KISN-KBIS AND
ESPECIALLY KDIK NOW THROUGH 15-17Z. INSTABILITY ALOFT HAS RESULTED
IN ISOLATED LIGHTNING STRIKES THIS MORNING...BUT TOO SPARSE TO ADD
A VCTS TO ANY SINGLE AERODROME AT THIS TIME.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...NH
LONG TERM...TWH
AVIATION...NH
AREA FORECAST DISCUSSION
NWS NORMAN OK
1038 PM CDT WED SEP 10 2014
.AVIATION...
6Z TAFS... MVFR/VFR CEILINGS EXPECTED THROUGH THE TAF PERIOD.
ISOLATED TO SCATTERED SHOWERS/STORMS WILL BE POSSIBLE THROUGH WED
EVENING MAINLY ACROSS THE SOUTHERN HALF OF THE AREA. HOWEVER...
CHANCES ARE TOO LOW AT THIS TIME FOR MENTION AT ANY ONE PARTICULAR
TAF SITE... BUT TRENDS WILL BE RE-EVALUATED BEFORE TAF ISSUANCE.
&&
.PREV DISCUSSION... /ISSUED 831 PM CDT WED SEP 10 2014/
UPDATE...
OVERALL FORECAST IN GOOD SHAPE. MOST OF THE ACTIVITY WILL LIKELY
REMAINED CONFINED TO SOUTH CENTRAL AND SOUTHEAST OKLAHOMA
OVERNIGHT. HOWEVER THERE REMAINS AT LEAST A SMALL CHANCE TO SEE SHOWER
DEVELOPMENT TO THE NORTH OF THE FRONT LATER TONIGHT NORTH TOWARD
CENTRAL SECTIONS OF OKLAHOMA. SO WILL LEAVE LOW POPS EVEN INTO
THE OKC METRO. OTHERWISE... JUST SOME MINOR TWEAKS TO THE CURRENT
GRIDS.
PREV DISCUSSION... /ISSUED 559 PM CDT WED SEP 10 2014/
AVIATION...
0Z TAFS... VFR/MVFR CEILINGS EXPECTED FOR THIS TAF PERIOD.
SHOWERS/STORMS WILL BE POSSIBLE ACROSS THE SOUTHERN HALF OF THE
AREA THROUGHOUT THE PERIOD BUT MOST LIKELY SITES TO RECEIVE RAIN
WILL BE OVER THE NEXT FEW HOURS IN CENTRAL OK W/STRONGEST STORMS
REMAINING SOUTH AND EAST OF THE TAF SITES.
PREV DISCUSSION... /ISSUED 356 PM CDT WED SEP 10 2014/
DISCUSSION...
THE INITIAL COLD FRONT IS CURRENTLY MOVING THROUGH SOUTHERN
OKLAHOMA AND WESTERN NORTH TEXAS. HRRR SUGGESTS THUNDERSTORMS MAY
STILL DEVELOP AHEAD OF THE FRONT IN FAR SOUTHERN OKLAHOMA AND
WESTERN NORTH TEXAS LATE AFTERNOON INTO THE EVENING. THERE WILL
ALSO BE POST-FRONTAL PRECIPITATION...SO KEPT POPS BEHIND THE
FRONT TONIGHT.
MOST AREAS SHOULD BE DRY DURING THE DAY TOMORROW. ONLY
A CHANCE ACROSS SOUTHERN OK AND WESTERN NORTH TX. A
SECONDARY...STRONGER COLD FRONT IS EXPECTED TO MOVE THROUGH THE
AREA ON FRIDAY. AHEAD OF THE SECONDARY FRONT...ISENTROPIC ASCENT
WILL BE PRESENT NEAR THE 305K SFC THURSDAY NIGHT INTO FRIDAY
MORNING. THE GREATEST ISENTROPIC ASCENT AND ELEVATED INSTABILITY
APPEARS TO BE ACROSS SOUTHERN OKLAHOMA...ESPECIALLY EAST OF I-35.
EXPECT SHOWERS AND THUNDERSTORMS DURING THIS PERIOD IN SOUTHERN
OKLAHOMA. THE ASCENT AND ASSOCIATED PRECIPITATION SHOULD WEAKEN BY
MID-MORNING.
THE AIR MASS BEHIND THIS FRONT IS FAIRLY COLD AND IS ORIGINATING
FROM A 1040 MB SFC HIGH IN WESTERN CANADA. THE FRONT APPEARS TO BE
A TYPICAL SHALLOW COLD FRONT WHERE A THERMAL TROUGH/PRESSURE RIDGE
DEVELOPS ACROSS THE HIGH PLAINS. LEANED TOWARD THE NAM12 BECAUSE
IT SEEMS TO HAVE A MORE REALISTIC REPRESENTATION OF SURFACE
FEATURES ON FRIDAY. BEHIND THE COLD FRONT...WIDESPREAD LOW CLOUDS
AND LIGHT PRECIPITATION/DRIZZLE WILL RESULT IN STEADY OR FALLING
TEMPERATURES DURING THE DAY FRIDAY. AREAS NORTH AND WEST WILL STAY
IN THE 50S ALL DAY. EVEN CENTRAL OKLAHOMA MAY SEE TEMPERATURES
FALL INTO THE 50S IN THE AFTERNOON. ASCENT SEEMS TO BE VERY WEAK
BEHIND THE FRONT...SO EXPECT VERY LIGHT PRECIPITATION TOTALS.
MAYBE SLIGHTLY HIGHER TOTALS IN NORTHWEST OK.
LOW-LEVEL DRY AIR WILL FLOW IN FROM THE NORTH FRIDAY NIGHT. SKIES
MAY CLEAR OUT ACROSS THE NORTHERN CWA. EXPECT SATURDAY MORNING
WILL BE THE COLDEST MORNING IN THE NEXT WEEK. 40S WILL BE LIKELY
NORTH OF I-40. IT WOULD NOT BE SURPRISING TO SEE A COUPLE UPPER
30S NEAR THE KANSAS BORDER IF SKIES CAN COMPLETELY CLEAR. SOUTH OF
I-40...STRONGER WINDS AND CLOUD COVER MAY KEEP TEMPERATURES FROM
BOTTOMING OUT. LOW TO MID 50S WILL BE POSSIBLE THERE.
SATURDAY...MOSTLY SUNNY SKIES ARE EXPECTED ACROSS THE NORTHERN TWO
THIRDS OF THE CWA. LOW-LEVEL RH FIELDS SUGGEST MORE WIDESPREAD
CLOUDS MAY STICK AROUND ACROSS FAR SOUTHERN OKLAHOMA AND WESTERN
NORTH TEXAS. HIGH TEMPERATURES WILL BE 10 TO 15 DEGREES BELOW
AVERAGE SATURDAY AFTERNOON.
AS A LEE TROUGH DEVELOPS...RETURN SOUTHERLY FLOW WILL RESULT IN A
MODERATING TREND ON SUNDAY. HIGHS WILL BE SEASONABLE IN THE LOW TO
MID 80S. A COLD FRONT WILL APPROACH NORTHERN OKLAHOMA LATE MONDAY
INTO TUESDAY. THERE IS SOME UNCERTAINTY ON HOW FAR SOUTH THE FRONT
WILL GO. NEVERTHELESS...THE FRONT AND NORTHWEST FLOW ALOFT SUGGEST
AT LEAST LOW POPS ARE NEEDED LATE MONDAY THROUGH WEDNESDAY.
MAHALE
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 62 76 61 65 / 30 10 30 40
HOBART OK 60 76 59 67 / 20 10 30 50
WICHITA FALLS TX 65 80 64 72 / 30 30 50 50
GAGE OK 53 73 51 58 / 10 10 30 50
PONCA CITY OK 57 75 55 63 / 10 10 20 40
DURANT OK 68 80 68 72 / 50 40 60 50
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
30/25/25
AREA FORECAST DISCUSSION
NWS TULSA OK
911 PM CDT WED SEP 10 2014
...UPDATE...
.DISCUSSION...
OUN SOUNDING CONTINUES TO SHOW RELATIVELY MOIST SOUTHWEST WINDS
ABOVE THE FRONT. THIS COULD SUPPORT ELEVATED PRECIPITATION AND
CONVECTION THROUGH THE NIGHT. RAP AND HRRR APPARENTLY SEE THIS AND
ALSO DEVELOP PRECIPITATION LATER IN THE NIGHT. BEST BET IS AGAIN
OVER WEST CENTRAL ARKANSAS INTO SOUTHEAST OKLAHOMA...GENERALLY
ALONG AND SOUTH OF I-40. LOWER CHANCES WILL EXTEND NORTHWARD...BUT
NOT ALL THE WAY TO THE KANSAS BORDER. WILL KEEP CHANCES IN THE
FORECAST FOR FAR NORTHWEST ARKANSAS ALSO.
LIGHT SHOWERS MOVING ACROSS PARTS OF NORTHEAST OK NOW. OTHER
SHOWERS AND ISOLATED THUNDERSTORM REDEVELOPING ALONG I-40 FROM
CHECOTAH TO THE WEST OF OKEMAH.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 61 76 61 65 / 40 10 30 50
FSM 70 75 66 71 / 70 50 50 70
MLC 66 75 66 68 / 70 50 60 60
BVO 58 74 58 66 / 20 10 20 40
FYV 63 73 60 67 / 60 40 40 60
BYV 62 72 58 66 / 60 30 40 50
MKO 63 77 63 66 / 50 20 40 60
MIO 59 73 57 66 / 20 10 20 40
F10 63 76 62 65 / 50 20 40 60
HHW 71 80 69 74 / 60 60 70 60
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
SHORT TERM...02
LONG TERM....02
AREA FORECAST DISCUSSION
NWS NORMAN OK
831 PM CDT WED SEP 10 2014
.UPDATE...
OVERALL FORECAST IN GOOD SHAPE. MOST OF THE ACTIVITY WILL LIKELY
REMAINED CONFINED TO SOUTH CENTRAL AND SOUTHEAST OKLAHOMA
OVERNIGHT. HOWEVER THERE REMAINS AT LEAST A SMALL CHANCE TO SEE SHOWER
DEVELOPMENT TO THE NORTH OF THE FRONT LATER TONIGHT NORTH TOWARD
CENTRAL SECTIONS OF OKLAHOMA. SO WILL LEAVE LOW POPS EVEN INTO
THE OKC METRO. OTHERWISE... JUST SOME MINOR TWEAKS TO THE CURRENT
GRIDS.
&&
.PREV DISCUSSION... /ISSUED 559 PM CDT WED SEP 10 2014/
AVIATION...
0Z TAFS... VFR/MVFR CEILINGS EXPECTED FOR THIS TAF PERIOD.
SHOWERS/STORMS WILL BE POSSIBLE ACROSS THE SOUTHERN HALF OF THE
AREA THROUGHOUT THE PERIOD BUT MOST LIKELY SITES TO RECEIVE RAIN
WILL BE OVER THE NEXT FEW HOURS IN CENTRAL OK W/STRONGEST STORMS
REMAINING SOUTH AND EAST OF THE TAF SITES.
PREV DISCUSSION... /ISSUED 356 PM CDT WED SEP 10 2014/
DISCUSSION...
THE INITIAL COLD FRONT IS CURRENTLY MOVING THROUGH SOUTHERN
OKLAHOMA AND WESTERN NORTH TEXAS. HRRR SUGGESTS THUNDERSTORMS MAY
STILL DEVELOP AHEAD OF THE FRONT IN FAR SOUTHERN OKLAHOMA AND
WESTERN NORTH TEXAS LATE AFTERNOON INTO THE EVENING. THERE WILL
ALSO BE POST-FRONTAL PRECIPITATION...SO KEPT POPS BEHIND THE
FRONT TONIGHT.
MOST AREAS SHOULD BE DRY DURING THE DAY TOMORROW. ONLY
A CHANCE ACROSS SOUTHERN OK AND WESTERN NORTH TX. A
SECONDARY...STRONGER COLD FRONT IS EXPECTED TO MOVE THROUGH THE
AREA ON FRIDAY. AHEAD OF THE SECONDARY FRONT...ISENTROPIC ASCENT
WILL BE PRESENT NEAR THE 305K SFC THURSDAY NIGHT INTO FRIDAY
MORNING. THE GREATEST ISENTROPIC ASCENT AND ELEVATED INSTABILITY
APPEARS TO BE ACROSS SOUTHERN OKLAHOMA...ESPECIALLY EAST OF I-35.
EXPECT SHOWERS AND THUNDERSTORMS DURING THIS PERIOD IN SOUTHERN
OKLAHOMA. THE ASCENT AND ASSOCIATED PRECIPITATION SHOULD WEAKEN BY
MID-MORNING.
THE AIR MASS BEHIND THIS FRONT IS FAIRLY COLD AND IS ORIGINATING
FROM A 1040 MB SFC HIGH IN WESTERN CANADA. THE FRONT APPEARS TO BE
A TYPICAL SHALLOW COLD FRONT WHERE A THERMAL TROUGH/PRESSURE RIDGE
DEVELOPS ACROSS THE HIGH PLAINS. LEANED TOWARD THE NAM12 BECAUSE
IT SEEMS TO HAVE A MORE REALISTIC REPRESENTATION OF SURFACE
FEATURES ON FRIDAY. BEHIND THE COLD FRONT...WIDESPREAD LOW CLOUDS
AND LIGHT PRECIPITATION/DRIZZLE WILL RESULT IN STEADY OR FALLING
TEMPERATURES DURING THE DAY FRIDAY. AREAS NORTH AND WEST WILL STAY
IN THE 50S ALL DAY. EVEN CENTRAL OKLAHOMA MAY SEE TEMPERATURES
FALL INTO THE 50S IN THE AFTERNOON. ASCENT SEEMS TO BE VERY WEAK
BEHIND THE FRONT...SO EXPECT VERY LIGHT PRECIPITATION TOTALS.
MAYBE SLIGHTLY HIGHER TOTALS IN NORTHWEST OK.
LOW-LEVEL DRY AIR WILL FLOW IN FROM THE NORTH FRIDAY NIGHT. SKIES
MAY CLEAR OUT ACROSS THE NORTHERN CWA. EXPECT SATURDAY MORNING
WILL BE THE COLDEST MORNING IN THE NEXT WEEK. 40S WILL BE LIKELY
NORTH OF I-40. IT WOULD NOT BE SURPRISING TO SEE A COUPLE UPPER
30S NEAR THE KANSAS BORDER IF SKIES CAN COMPLETELY CLEAR. SOUTH OF
I-40...STRONGER WINDS AND CLOUD COVER MAY KEEP TEMPERATURES FROM
BOTTOMING OUT. LOW TO MID 50S WILL BE POSSIBLE THERE.
SATURDAY...MOSTLY SUNNY SKIES ARE EXPECTED ACROSS THE NORTHERN TWO
THIRDS OF THE CWA. LOW-LEVEL RH FIELDS SUGGEST MORE WIDESPREAD
CLOUDS MAY STICK AROUND ACROSS FAR SOUTHERN OKLAHOMA AND WESTERN
NORTH TEXAS. HIGH TEMPERATURES WILL BE 10 TO 15 DEGREES BELOW
AVERAGE SATURDAY AFTERNOON.
AS A LEE TROUGH DEVELOPS...RETURN SOUTHERLY FLOW WILL RESULT IN A
MODERATING TREND ON SUNDAY. HIGHS WILL BE SEASONABLE IN THE LOW TO
MID 80S. A COLD FRONT WILL APPROACH NORTHERN OKLAHOMA LATE MONDAY
INTO TUESDAY. THERE IS SOME UNCERTAINTY ON HOW FAR SOUTH THE FRONT
WILL GO. NEVERTHELESS...THE FRONT AND NORTHWEST FLOW ALOFT SUGGEST
AT LEAST LOW POPS ARE NEEDED LATE MONDAY THROUGH WEDNESDAY.
MAHALE
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 62 76 61 65 / 20 10 30 40
HOBART OK 60 76 59 67 / 20 10 30 50
WICHITA FALLS TX 65 80 64 72 / 40 30 50 50
GAGE OK 53 73 51 58 / 10 10 30 50
PONCA CITY OK 57 75 55 63 / 10 10 20 40
DURANT OK 68 80 68 72 / 60 40 60 50
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
30/25
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
907 PM CDT WED SEP 10 2014
.UPDATE...
A QUICK MOVING SHORT WAVE TROUGH WAS BRINGING SOME LIGHT RAIN SHOWERS
TO THE REGION THIS EVENING. THIS WILL MOVE ON TO THE EAST AFTER MIDNIGHT
WHILE NEW DEVELOPMENT MOVES INTO THE WEST AND SOUTHWEST PARTS OF
THE CWA WITH THE MAIN UPPER LOW PRESSURE TROUGH. ADJUSTED POPS FOR
THE NIGHT...MAINLY ACROSS THE NORTHERN CWA. UPDATED FORECAST.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT
CLOUDY AND COLD IS THE STORY ACROSS THE REGION THIS AFTERNOON. IN
FACT...SOME LOCATIONS WILL LIKELY SET RECORDS FOR THE COLDEST
HIGH TEMPERATURE EVER RECORDED ON THIS DATE. CWA IS CURRENTLY DRY
BUT WATCHING THE BEGINNINGS OF THE NEXT SYSTEM MOVING ACROSS
NORTHWEST SD. TREND FOR TONIGHT WILL BE FOR PRECIP TO MAINLY
AFFECT WESTERN AND CENTRAL SD...AND MAY EVEN GET COLD ENOUGH LATE
TONIGHT AND EARLY THURSDAY MORNING TO ALLOW FOR A RAIN/SNOW MIX
ACROSS THE FAR NORTHWEST CWA. TARGET AREA FOR ACCUMULATING SNOW
THOUGH STILL REMAINS OVER FAR WESTERN SD AND THE BLACK HILLS. WILL
HAVE TO WATCH CLOUD COVER TRENDS OVERNIGHT ACROSS THE
NORTHERN/NORTHEAST CWA AS CIGS HAVE THINNED AND HAVE EVEN REVEALED
SOME HOLES. RAP MODEL 925-850MB RH SHOWS THIS DRIER AREA
NICELY...AND BRINGS IN OVER THE NORTHERN COUNTIES LATER TONIGHT.
IF ANY BREAKS OR THINNING OCCUR...TEMPS COULD FALL PRETTY NICELY.
BUT OVERALL...THE ABUNDANCE OF MID AND HIGH CLOUDS WITH THE NEXT
APPROACHING WAVE...AND THE OVERALL WINDS STAYING UP A TOUCH SHOULD
PREVENT THE BOTTOM FROM FALLING OUT ON TEMPS.
ATTENTION THEN TURNS TO THURSDAY NIGHT AND FRIDAY MORNING AND THE
POTENTIAL FOR FROST. MODELS CONTINUE TO SHIFT PRECIP AND CLOUDS A
BIT FURTHER SOUTH AND EAST DURING THIS TIME...A BIT QUICKER THAN
PREVIOUS RUNS...AND THE PREVIOUSLY SLOWER EC IS NOW COMING AROUND
TO THE FASTER SOLUTIONS OTHER MODELS HAVE BEEN SHOWING. THIS MEANS
A BETTER POTENTIAL FOR FROST CONDITIONS AND TEMPS IN THE LOW TO
MID 30S OVER A GOOD PORTION OF THE CWA. INSERTED FROST INTO THE
GRIDS ALONG AND WEST OF THE JAMES VALLEY AND COULD VERY WELL BE
HEADING TOWARDS A FROST ADVISORY AT SOME POINT. IT WILL ALL DEPEND
ON HOW MUCH CLOUD COVER LINGERS OVER THE AREA...THE CLEARER THE
SKIES THE BETTER THE TEMPS WILL FALL.
FOR FRIDAY NIGHT AND SATURDAY...MODELS SEEM TO BE NUDGING THE HIGH
CENTER TO THE EAST A TAD QUICKER. WHAT THIS MEANS IS THAT A
SLIGHTLY STRONGER GRADIENT SETS UP FRIDAY NIGHT WITH SOUTH WINDS
PICKING UP. WHETHER OR NOT THESE WINDS ARE STRONG ENOUGH ALONG AND
EAST OF THE JAMES VALLEY TO PREVENT TEMPS FROM REACHING THE LOW TO
MID 30S IS DOUBTFUL. WEST OF THERE...PROBABLY YES. CANNOT RULE OUT
FROST FRIDAY NIGHT/SATURDAY MORNING EITHER...BUT BEST POTENTIAL
HERE WILL BE ACROSS THE EASTERN CWA.
.LONG TERM...SATURDAY THROUGH WEDNESDAY
NOT MUCH CHANGE IN THE EXTENDED FROM 24 HOURS AGO. 12Z MODEL
SOLUTIONS POINT TO A BIT OF WARMING ON SATURDAY OUT AHEAD OF AN
APPROACHING COLD FRONT. ANOTHER SURFACE HIGH PRESSURE SYSTEM
BUILDS DOWN FOR SUNDAY AND MONDAY...BUT THEN SHIFTS SOUTH AND EAST
OF THE AREA...ALLOWING FOR RETURN FLOW WARMING WINDS TUESDAY AND
WEDNESDAY. PRECIPITATION CHANCES REALLY ARE FEW AND FAR BETWEEN IN
THE OUT PERIODS...WITH THE "BEST" CHANCES FOR A FEW RAIN
SHOWERS SHOWING UP SUNDAY AFTERNOON/EVENING BEHIND THIS COLD
FROPA.
&&
.AVIATION...
00Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
A QUICK MOVING SHORT WAVE TROUGH WILL BRING SOME LIGHT RAIN
SHOWERS TO MBG AND ABR THIS EVENING AND POSSIBLY TO ATY TOWARDS
MIDNIGHT. OTHERWISE...LIFT FROM THE MAIN UPPER LOW PRESSURE AREA
DROPPING IN FROM THE NORTHWEST TONIGHT WILL BRING SHOWERS INTO THE
PIERRE AREA THIS EVENING...REMAINING THROUGH THURSDAY MORNING.
CEILINGS ARE EXPECTED TO BE MAINLY VFR FOR MBG...ABR AND ATY
THROUGH THE PERIOD...EXCEPT FOR PIR WHERE THEY SHOULD BE MAINLY
MVFR. VISIBILITIES COULD BE REDUCED AT PIR WITH SOME HEAVIER RAIN
SHOWERS.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...MOHR
SHORT TERM...TMT
LONG TERM...DORN
AVIATION...MOHR
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
702 PM CDT WED SEP 10 2014
.UPDATE...
00Z AVIATION DISCUSSION UPDATED BELOW.
&&
.SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT
CLOUDY AND COLD IS THE STORY ACROSS THE REGION THIS AFTERNOON. IN
FACT...SOME LOCATIONS WILL LIKELY SET RECORDS FOR THE COLDEST
HIGH TEMPERATURE EVER RECORDED ON THIS DATE. CWA IS CURRENTLY DRY
BUT WATCHING THE BEGINNINGS OF THE NEXT SYSTEM MOVING ACROSS
NORTHWEST SD. TREND FOR TONIGHT WILL BE FOR PRECIP TO MAINLY
AFFECT WESTERN AND CENTRAL SD...AND MAY EVEN GET COLD ENOUGH LATE
TONIGHT AND EARLY THURSDAY MORNING TO ALLOW FOR A RAIN/SNOW MIX
ACROSS THE FAR NORTHWEST CWA. TARGET AREA FOR ACCUMULATING SNOW
THOUGH STILL REMAINS OVER FAR WESTERN SD AND THE BLACK HILLS. WILL
HAVE TO WATCH CLOUD COVER TRENDS OVERNIGHT ACROSS THE
NORTHERN/NORTHEAST CWA AS CIGS HAVE THINNED AND HAVE EVEN REVEALED
SOME HOLES. RAP MODEL 925-850MB RH SHOWS THIS DRIER AREA
NICELY...AND BRINGS IN OVER THE NORTHERN COUNTIES LATER TONIGHT.
IF ANY BREAKS OR THINNING OCCUR...TEMPS COULD FALL PRETTY NICELY.
BUT OVERALL...THE ABUNDANCE OF MID AND HIGH CLOUDS WITH THE NEXT
APPROACHING WAVE...AND THE OVERALL WINDS STAYING UP A TOUCH SHOULD
PREVENT THE BOTTOM FROM FALLING OUT ON TEMPS.
ATTENTION THEN TURNS TO THURSDAY NIGHT AND FRIDAY MORNING AND THE
POTENTIAL FOR FROST. MODELS CONTINUE TO SHIFT PRECIP AND CLOUDS A
BIT FURTHER SOUTH AND EAST DURING THIS TIME...A BIT QUICKER THAN
PREVIOUS RUNS...AND THE PREVIOUSLY SLOWER EC IS NOW COMING AROUND
TO THE FASTER SOLUTIONS OTHER MODELS HAVE BEEN SHOWING. THIS MEANS
A BETTER POTENTIAL FOR FROST CONDITIONS AND TEMPS IN THE LOW TO
MID 30S OVER A GOOD PORTION OF THE CWA. INSERTED FROST INTO THE
GRIDS ALONG AND WEST OF THE JAMES VALLEY AND COULD VERY WELL BE
HEADING TOWARDS A FROST ADVISORY AT SOME POINT. IT WILL ALL DEPEND
ON HOW MUCH CLOUD COVER LINGERS OVER THE AREA...THE CLEARER THE
SKIES THE BETTER THE TEMPS WILL FALL.
FOR FRIDAY NIGHT AND SATURDAY...MODELS SEEM TO BE NUDGING THE HIGH
CENTER TO THE EAST A TAD QUICKER. WHAT THIS MEANS IS THAT A
SLIGHTLY STRONGER GRADIENT SETS UP FRIDAY NIGHT WITH SOUTH WINDS
PICKING UP. WHETHER OR NOT THESE WINDS ARE STRONG ENOUGH ALONG AND
EAST OF THE JAMES VALLEY TO PREVENT TEMPS FROM REACHING THE LOW TO
MID 30S IS DOUBTFUL. WEST OF THERE...PROBABLY YES. CANNOT RULE OUT
FROST FRIDAY NIGHT/SATURDAY MORNING EITHER...BUT BEST POTENTIAL
HERE WILL BE ACROSS THE EASTERN CWA.
.LONG TERM...SATURDAY THROUGH WEDNESDAY
NOT MUCH CHANGE IN THE EXTENDED FROM 24 HOURS AGO. 12Z MODEL
SOLUTIONS POINT TO A BIT OF WARMING ON SATURDAY OUT AHEAD OF AN
APPROACHING COLD FRONT. ANOTHER SURFACE HIGH PRESSURE SYSTEM
BUILDS DOWN FOR SUNDAY AND MONDAY...BUT THEN SHIFTS SOUTH AND EAST
OF THE AREA...ALLOWING FOR RETURN FLOW WARMING WINDS TUESDAY AND
WEDNESDAY. PRECIPITATION CHANCES REALLY ARE FEW AND FAR BETWEEN IN
THE OUT PERIODS...WITH THE "BEST" CHANCES FOR A FEW RAIN
SHOWERS SHOWING UP SUNDAY AFTERNOON/EVENING BEHIND THIS COLD
FROPA.
&&
.AVIATION...
00Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
A QUICK MOVING SHORT WAVE TROUGH WILL BRING SOME LIGHT RAIN
SHOWERS TO MBG AND ABR THIS EVENING AND POSSIBLY TO ATY TOWARDS
MIDNIGHT. OTHERWISE...LIFT FROM THE MAIN UPPER LOW PRESSURE AREA
DROPPING IN FROM THE NORTHWEST TONIGHT WILL BRING SHOWERS INTO THE
PIERRE AREA THIS EVENING...REMAINING THROUGH THURSDAY MORNING.
CEILINGS ARE EXPECTED TO BE MAINLY VFR FOR MBG...ABR AND ATY
THROUGH THE PERIOD...EXCEPT FOR PIR WHERE THEY SHOULD BE MAINLY
MVFR. VISIBILITIES COULD BE REDUCED AT PIR WITH SOME HEAVIER RAIN
SHOWERS.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...MOHR
SHORT TERM...TMT
LONG TERM...DORN
AVIATION...MOHR
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
952 PM CDT WED SEP 10 2014
.UPDATE...
SEE EVENING UPDATE.
&&
.DISCUSSION...
AT 8 PM...A COLD FRONT EXTENDED FROM FT SMITH TO NEAR SHERMAN TO
BIG SPRINGS. AT 850 MB...A TROUGH OF LOW PRESSURE EXTENDED NORTH
TO SOUTH ACROSS WEST TEXAS WITH DEEP 850 MOISTURE OVER OK...AR
AND NE TX. ANOTHER WEAK TROUGH WAS NOTED BETWEEN OKC AND DFW. 850
TEMPS WERE -3 C AT GLASGOW MT WHICH IS PRETTY COOL FOR THIS TIME
OF YEAR. A POOL OF DEEPER 700 MB MOISTURE WAS LOCATED OVER N TX
AND S OK WITH A WEAK TROUGH OVER SW TX. AT 250 MB...A BROAD TROUGH
WAS LOCATED OVER THE CENTRAL PLAINS WITH UPPER LEVEL RIDGING
EXTENDING FROM THE SOUTHERN APPALACIANS ACROSS COASTAL TEXAS. 00Z
MODEL RUNS ARE JUST COMING IN BUT SHORT TERM GUIDANCE IS TRENDING
WETTER FOR THURSDAY. THE RAP IN PARTICULAR BRINGS IN SLIGHTLY
HIGHER MOISTURE EARLY THURSDAY MORNING COURTESY OF A BROAD
EASTERLY WAVE THAT EXTENDS FROM THE MS COAST TO THE MEXICAN COAST.
00Z SOUNDINGS CAME IN DRY AND GPS MET NETWORK SHOWS PW VALUES
AROUND 1.6 INCHES WHICH IS ON THE DRY SIDE FOR EARLY SEPT. YET THE
RAP AND TO A LESSER EXTENT THE HRRR...ARW AND TEXAS TECH WRF SHOW
SHRA/TSRA DEVELOPING BY 13Z AND SPREADING INLAND. THE RAP ALSO
BRINGS A WIND SHIFT TO THE COLLEGE STATION AREA AROUND 18Z.
PRESSURE RISES BEHIND THE FRONT ARE NOT THAT IMPRESSIVE SO PREFER
THE NAM 12 FOR FRONTAL TIMING. ADDED POPS FOR LATE TONIGHT ALONG
THE COAST AND ADDED MORNING POPS FOR AREAS SOUTH OF I-10. NEW
ZONES OUT BY 10 PM. 43
&&
.CLIMATE...
CRUNCHING SOME NUMBERS TONIGHT ON RAINFALL DEFICITS ACROSS THE
AREA. GALVESTON IS OVER 75 INCHES BELOW NORMAL SINCE JAN 1 2009.
HOBBY AIRPORT IS NOT THAT FAR BEHIND AND IS 65 INCHES BELOW NORMAL
SINCE 2009. HOPEFULLY RAIN THIS WEEKEND WILL PUT A DENT INTO SOME
THESE NUMBERS.
HURRICANE CARLA MADE LANDFALL ON SEPT 11 1961. IT`S THE LAST CAT 4
TO AFFECT THE UPPER TEXAS COAST. CARLA WAS BRIEFLY A CAT 5 OVER
THE GULF. 43
&&
.PREV DISCUSSION... /ISSUED 627 PM CDT WED SEP 10 2014/
DISCUSSION...
SEE THE 00Z AVIATION DISCUSSION BELOW.
40
AVIATION...
VFR IS EXPECTED FOR THE MOST PART THROUGH THURSDAY AFTERNOON. MVFR
IS MOST LIKELY BETWEEN 09Z AND 15Z AT KCXO...KUTS...KCLL...AND
KLBX. CONDITIONS MAY LOWER TO MVFR AT KSGR AS WELL. THE SURFACE
PRESSURE GRADIENT IS FORECAST TO RELAX. THIS WILL IN TURN LOWER
THE WIND SPEEDS ACROSS THE AREA ON THURSDAY. DO EXPECT THE
SEABREEZE TO BECOME MORE ACTIVE AFTER AROUND 18Z.
40
PREV DISCUSSION... /ISSUED 322 PM CDT WED SEP 10 2014/
DISCUSSION...
PARTLY CLOUDY SKIES THIS AFTERNOON WITH ONLY A SHOWER OR TWO
THANKS TO UPPER LEVEL RIDGING AND NEAR NORMAL MOISTURE VALUES FOR
THIS TIME OF YEAR. ANOTHER HOT DAY EXPECTED TOMORROW AS A FRONT
WILL SLOWLY PUSH TO THE SOUTH ALLOWING 850 TEMPERATURES TO REMAIN
AROUND 20C. FORECAST SOUNDINGS ALSO SHOW PLENTY OF DRY AIR BETWEEN
600 AND 300 MB. THIS SHOULD HELP TO LIMIT SHOWER AND THUNDERSTORM
ACTIVITY FOR THURSDAY.
ON FRIDAY THE UPPER LEVEL RIDGE WILL BEGIN TO FLATTEN AS A
SECONDARY PIECE OF MID LEVEL ENERGY CURRENTLY OVER MONTANA DIVES
TO THE SOUTH. THIS SECONDARY SURGE OF ENERGY WILL HELP TO PUSH THE
FRONT TO THE COAST SATURDAY MORNING. THE DRIER AND COOLER AIR
WILL REMAIN NORTH OF THE AREA THOUGH. LATE FRIDAY INTO SATURDAY
THE FRONT WILL BE SLOWLY PUSHING THROUGH THE AREA WHICH WILL HELP
INITIATE SHOWER AND THUNDERSTORMS ACTIVITY. GFS IS SHOWING PWATS
CLIMBING TO NEAR 2.30" AHEAD OF THE BOUNDARY (NEAR THE 99TH
PERCENTILE FOR THIS TIME OF YEAR). AT THE SAME TIME A WEAK
DISTURBANCE WILL PUSH INTO MEXICO BRINGING MOIST AIR INTO TEXAS
FROM THE SOUTH. OMEGA FIELDS FROM BOTH THE NAM AND GFS SHOW LIFT
STARTING ALONG A SEA BREEZE FRIDAY AFTERNOON WITH ANOTHER AREA OF
LIFT MOVING IN FROM THE NORTH IN ASSOCIATION WITH FRONT. MAIN
CONCERN FOR FRIDAY AFTERNOON INTO SATURDAY MORNING WILL BE THE
CHANCE OF HEAVY RAIN. FORECAST SOUNDINGS ARE SHOWING STORM
MOTIONS IN THE 5 TO 10 KT RANGE.
AS SATURDAY PROGRESSES THE SHORTWAVE THAT MOVED SOUTH FROM
MONTANA WILL QUICKLY PULL TO THE EAST TAKING THE COOLER AIR WITH
IT. THROUGH THE FIRST PART OF NEXT WEEK BOTH THE ECMWF AND GFS
KEEP THE AREA IN A NORTHWEST FLOW AT THE MID LEVELS. NOT
SURPRISINGLY THIS ALSO ALLOWS FOR UPPER LEVEL DISTURBANCES TO
MOVE ACROSS THE AREA. BECAUSE OF THIS WILL KEEP POPS IN THE
FORECAST THROUGH THE END OF THE PERIOD. 23
MARINE...
AN INCREASE BACK TO 10-15 KNOTS TONIGHT AND AGAIN THURSDAY EVENING
THEN WILL BE FOLLOWED BY LIGHTER WINDS FRIDAY AS THE FRONT SETTLES
INTO SOUTHEAST TEXAS IN THE AFTERNOON. WINDS ACROSS THE UPPER
TEXAS COASTAL WATERS WILL BACK TO THE EAST AND BE INCREASING
FRIDAY NIGHT AS THE FRONT NEARS. THIS SHOULD IN TURN LEAD TO
SLIGHTLY ABOVE NORMAL TIDE LEVELS FRIDAY NIGHT THROUGH SUNDAY.
SCATTERED SHOWERS AND THUNDERSTORMS WILL BE ON TAP FRIDAY THROUGH
SUNDAY WITH THE CLOSE PROXIMITY OF THE FRONT AND ABUNDANT MOISTURE
POOLED OVER THE AREA. 45
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 77 97 75 90 71 / 10 20 30 60 60
HOUSTON (IAH) 77 96 77 91 74 / 10 20 30 60 60
GALVESTON (GLS) 83 91 82 90 79 / 20 20 30 60 60
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...43
AREA FORECAST DISCUSSION...UPDATED
NWS SAN ANGELO TX
858 PM CDT WED SEP 10 2014
.UPDATE...
The cold front is making better progress this evening than
earlier anticipated, and at 8 PM extended from just south of
Breckenridge to the south edge of Abilene to just north of
Maryneal. The RUC13 appears to have the best handle on this
front in the near term, taking the boundary south to a
Richland Springs-San Angelo-Barnhart line by Midnight,
then stalling somewhere over the central part of our area
overnight. Isolated convection has been occurring in our
Heartland (east-central) counties this evening. Isolated to
scattered showers and thunderstorms are expected to develop
along the front tonight. Made a few minor PoP changes based
on the RUC, and adjusted the winds to account for a faster
frontal passage across the northern half of our area. Will
monitor radar and observational trends and make any further
updates as needed.
19
&&
.PREV DISCUSSION... /ISSUED 616 PM CDT WED SEP 10 2014/
AVIATION...
/00Z TAFS/
VFR conditions will prevail across all terminals through approx
10Z. Showers and thunderstorms will be possible with the passage of
the cold front through the KABI terminal this evening. Periods of
MVFR CIGS, lower VSBY and brief gusty winds may accompany these
storms. The development of MVFR CIGS will also be possible early
tomorrow morning as cold air continues moves into the area. MVFR
CIGS are expected to develop across the southern terminals as early
as 11Z and persist through noon.
18
PREV DISCUSSION... /ISSUED 330 PM CDT WED SEP 10 2014/
SHORT TERM...
(Tonight and Thursday)
The cold front currently located from Andrews to Vernon in the
southern Panhandle will be along the Interstate 20 corridor by
mid-evening. There is good agreement amongst the models, including
the high res models, that scattered convection will break out along
the front. The best chances before midnight will remain along and
just north of Interstate 20.
The front will make south to San Angelo shortly after midnight. A
few thunderstorms will be possible mainly north of a line from
Sterling City, to San Angelo, to San Saba. The front looks to stall
just south of that line, with convection becoming more isolated.
However, if good outflow develops with the convection, it may be
possible that the effective front may push convection further south,
along with more thunderstorms.
Thunderstorms are expected again tomorrow, as the front remains
mostly stationary. Current guidance has most of the activity south
of a line from San Angelo to Brownwood, however the exact location
is going to be very dependent on where the front ends up.
For temperatures, guidance continues to show much cooler
temperatures than today. The Big Country will see mostly cloudy
skies with north winds, and temperatures in the low to mid 80s.
Elsewhere cloud cover won`t be quite as much, so temperatures will a
little warmer, generally in the upper 80s to lower 90s.
Reimer
LONG TERM...
(Thursday Night through Wednesday)
Unseasonably post-frontal cold air will result in afternoon highs
only in the upper 60s over the Big Country on Friday after morning
lows in the mid 60s. Afternoon highs in areas south of Interstate 20
on Friday will be in the upper 70s to the lower 80s after morning
lows in the lower 70s. A reinforcing shot of cold air on Friday will
push the cold front well south of the forecast area over the
weekend, keeping the unseasonably cool temperatures over all of West
Central Texas through the weekend and into the first of next week.
Morning lows will drop into the 50s over the northern half of the
CWA on Saturday morning with morning lows remaining in the 60s over
all of West Central Texas through next Wednesday. Afternoon highs in
the 70s over all of West Central Texas on Saturday will warm into
the lower 80s on Sunday and Monday.
Isentropic lift over the frontal boundary will keep the chance of
showers and thunderstorms over most of the area into the beginning
of the coming week. With model forecast soundings still indicating
precipitable water values in the 1.5 to 1.75 inches range, localized
flooding from heavy rainfall will remain a threat.
15
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 70 84 67 73 57 / 40 40 50 60 20
San Angelo 72 90 72 80 60 / 30 40 40 40 30
Junction 73 92 73 86 67 / 20 30 40 50 40
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
643 PM CDT WED SEP 10 2014
UPDATED...AVIATION PORTION FOR 00Z TAF ISSUANCE AND HYDROLOGY PORTION.
.SHORT TERM...TONIGHT AND THURSDAY
ISSUED AT 242 PM CDT WED SEP 10 2014
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A STRONG
LOW PRESSURE SYSTEM TRACKING NORTHEAST TOWARDS MANITOWOC WHILE A
POTENT COLD FRONT IS DROPPING SOUTHEAST FROM THE BAY OF GREEN BAY TO
JUST WEST OF OSHKOSH. MOST OF THE HEAVIER RAINFALL HAS EXITED THE
REGION TO THE NORTHEAST EXCEPT FOR FAR WESTERN ONEIDA AND VILAS
COUNTIES. AREAS OF DRIZZLE OR VERY LIGHT RAIN WILL GRADUALLY
DIMINISH THROUGH THE REST OF THE AFTERNOON AS THE CYCLONE EXITS THE
REGION. OBSERVATIONS INDICATE A WIDESPREAD 1.5 TO 2.5 INCHES OF
RAIN OVER NORTH-CENTRAL WISCONSIN FOR A STORM TOTAL. AREA RIVERS
SEEM TO BE HOLDING UP WELL AND HAVE RECEIVED NO REPORTS OF FLOODING
SO FAR. WILL LET THE FLOOD WATCH EXPIRE WITH THIS FORECAST
ISSUANCE. GUSTY NORTHWEST WINDS ARE USHERING IN THE FIRST TASTE OF
FALL BEHIND THE COLD FRONT. TEMPERATURES ARE FALLING INTO THE 40S
AND 50S BEHIND THE FRONT...WHILE READINGS REMAIN IN THE 60S AND 70S
AHEAD OF THE FRONT. TIMING THE END OF THE PRECIP...TEMPS...AND
MARINE HEADLINES ARE THE MAIN FORECAST CONCERNS.
TONIGHT...LOW PRESSURE WILL CONTINUE TO MOVE TO THE NORTHEAST INTO
EASTERN ONTARIO AND WESTERN QUEBEC WHILE THE STRONG COLD FRONT MOVES
EAST ACROSS THE LOWER PENINSULA OF MICHIGAN. BEHIND THE
FRONT...GUSTY NORTHWEST WINDS WILL USHER IN A MIGHTY CHILLY AIRMASS
FOR THIS TIME OF THE YEAR. WITH LOW INVERSION HEIGHTS OF AROUND
875MB...THE AIRMASS WILL BE PLENTY COLD ENOUGH TO SUPPORT LAKE
EFFECT RAIN SHOWERS OFF LAKE SUPERIOR...WHICH WILL LIKELY JUST
IMPACT VILAS COUNTY AS WIND TRAJECTORIES ARE TOO NORTHERLY FOR A
DIRECT HIT. PLENTY OF LOW STRATUS UPSTREAM BENEATH THIS
INVERSION...AND WITH MOISTURE FLUXES OFF LAKE SUPERIOR COMBINED WITH
THERMAL TROUGHING...HAVE A TOUGH TIME SEEING ANY SORT OF CLEARING
TAKING PLACE. PERHAPS A FEW HOLES IN THE OVERCAST IN THE
DOWNSLOPING AREAS OF NORTHEAST WISCONSIN. LOWS FALLING INTO THE
UPPER 30S NORTH TO UPPER 40S SOUTHEAST.
THURSDAY...850MB TEMPERATURES CONTINUE TO FALL AS CANADIAN HIGH
PRESSURE BUILDS TOWARDS THE REGION. THE INVERSION WILL REMAIN STOUT
ABOVE STEEP LOW LEVEL LAPSE RATES. AS A RESULT...CLOUDY CONDITIONS
IN THE MORNING WILL BE SLOW TO BREAK UP...ESPECIALLY WITH MID-LEVEL
CLOUDS ARRIVING IN THE AFTERNOON. SO EXPECT SKY CONDITIONS TO
REMAIN AT LEAST PARTLY SUNNY OR MOSTLY CLOUDY THROUGH THE
DAY. HIGHS RANGING FROM THE UPPER 40S NORTH TO MIDDLE 50S SOUTH.
.LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY
ISSUED AT 242 PM CDT WED SEP 10 2014
LARGE SURFACE HIGH SHOULD COVER THE NORTHERN AND
CENTRAL PLAINS ALL THE WAY EAST TO THE GREAT LAKES AND NORTHERN
OHIO VALLEY THURSDAY NIGHT THROUGH FRIDAY EVENING. WHILE THIS
WOULD NORMALLY RESULT IN A DRY FORECAST AND CLEAR SKIES THERE IS A
SHARP UPPER LEVEL TROUGH THAT WILL BE MOVING ACROSS WISCONSIN
FRIDAY AND FRIDAY EVENING THAT SHOULD BE STRONG ENOUGH TO PRODUCE
SOME LIGHT RAIN DESPITE SURFACE HIGH PRESSURE AND DRY AIR IN THE
LOW LEVELS. THE CLOUDS AND LIGHT RAIN SHOULD KEEP HIGH TEMPERATURES
LOWER THAN MOS GUIDANCE FRIDAY SO WENT ABOUT 3 DEGREES LOWER IN
MOST PLACES.
LOW TEMPERATURES SATURDAY MORNING WILL DEPEND ON HOW QUICKLY THE
UPPER SYSTEM EXITS FRIDAY NIGHT AND HOW QUICKLY SKIES CLEAR. THE
ECMWF IS SLOWER THAN THE GFS AND ITS SOLUTION WOULD KEEP CLOUDS
ALL NIGHT AND HOLD TEMPERATES UP. WE ARE SIDING WITH THE QUICKER
GFS AND THUS WENT LOWER THAN GUIDANCE FOR LOWS FRIDAY NIGHT.
NICE WEATHER EXPECTED SATURDAY THROUGH SUNDAY WITH A SLIGHT CHANCE
OF SHOWERS SUNDAY EVENING AS THE NEXT UPPER TROUGH APPROACHES.
THAT SYSTEM SHOULD BRING SHOWERS SUNDAY NIGHT AND MONDAY.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 636 PM CDT WED SEP 10 2014
CIGS MAINLY BETWEEN 1000 TO 2000 FT OVERNIGHT. VERY SLOW
IMPROVEMENT IN CIGS EXPECTED ON WEDNESDAY WITH SOME BREAKING UP OF
THE CLOUD COVER DURING THE AFTERNOON.
WIND GUSTS OF 25 TO 30 KTS EARLY THIS EVENING GRADUALLY DECREASING
AFTER 01Z.
&&
.MARINE...
ISSUED AT 242 PM CDT WED SEP 10 2014
NORTHWEST WINDS WILL RAPIDLY STRENGTHEN LATE THIS
AFTERNOON INTO EARLY THIS EVENING BEHIND A DEPARTING LOW PRESSURE
SYSTEM. WITH INCREASING INSTABILITY OVER THE CENTRAL BAY OF GREEN
BAY...MIXING WILL SUPPORT 40 TO 45 KT WINDS AT 925 AND 900MB TO
REACH THE SURFACE. THIS WIND DIRECTION IS ALSO FAVORABLE FOR HIGHER
END GUSTS THROUGH DEATHS DOOR. ISSUE A GALE WARNING FOR THE CENTRAL
BAY AND LAKE MICHIGAN SHORELINE THROUGH 18Z...THOUGH GALES WILL
LIKELY ONLY BE POSSIBLE THROUGH SUNRISE ON THURSDAY.
&&
.HYDROLOGY...
ISSUED AT 636 PM CDT WED SEP 10 2014
NORTH-CENTRAL WISCONSIN PICKED UP THE MOST RAINFALL FOR THIS
EVENT...WITH SCATTERED LOCATIONS REACHING 2 TO 3 INCHES. RIVERS
STARTING TO RESPOND...WITH A COUPLE NEAR BANKFULL. BIG RIB RIVER
IN MARATHON COUNTY AT FLOOD STAGE...BUT NO SIGNIFICANT PROBLEMS ATTM.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......JKL
MARINE.........MPC
HYDROLOGY......JKL
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND WEDNESDAY
ISSUED AT 245 PM CDT TUE SEP 9 2014
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A STRONG
COLD FRONT MOVING SOUTHEAST ACROSS NORTHERN MINNESOTA AND SOUTH
DAKOTA...WHILE LOW PRESSURE IS EMERGING INTO WESTERN KANSAS. AN
ISOLATED THUNDERSTORM DROPPED A QUARTER OF AN INCH OF RAIN OVER
WAUSAU EARLIER THIS MORNING WITHIN A MODEST MOISTURE AXIS BUT
DIMINISHED BY MIDDAY. OTHERWISE...NO OTHER CONVECTION HAS DEVELOPED
SO FAR TODAY. THUNDERSTORM ACTIVITY CONTINUES TO EXPAND OVER
NEBRASKA AND IOWA IN AN AREA OF MOISTURE CONVERGENCE AT 850MB. AS
LOW PRESSURE MOVES EAST AND THE LLJ MATURES THIS EVENING...THIS AREA
WILL DRAW ATTENTION FOR THE POTENTIAL OF SEVERE WEATHER AND HEAVY
RAIN DOWNSTREAM OVER CENTRAL AND NORTHEAST WISCONSIN LATER TONIGHT.
ANOTHER AREA OF RAIN CONTINUES TO DEVELOP OVER THE EASTERN DAKOTAS.
AS THESE SYSTEMS MOVE EAST...SEVERE WEATHER AND HEAVY RAIN POTENTIAL
ARE THE MAIN FORECAST CONCERNS.
TONIGHT...FOLLOWED THE ECMWF AND SREF FOR THE DETAILS OF THIS
FORECAST...WHICH IS PREFERRED BY HPC AND SUPPORTED BY THE ENSEMBLE
MEANS. THESE MODELS SHOW THAT THE STRONG COLD FRONT OVER THE
NORTHERN PLAINS WILL SAG SOUTH INTO NORTH-CENTRAL WISCONSIN THIS
EVENING AS LOW PRESSURE TRACKS NORTHEAST ACROSS THE CENTRAL PLAINS.
AHEAD OF THIS LOW...MID-LEVEL FLOW WILL BE BACKING WHILE INCREASING
AT THE SAME TIME...LEADING TO INCREASING ISENTROPIC ASCENT IN THE
PRESENCE OF MID-LEVEL LAPSE RATES BETWEEN 6-7 C/KM THROUGH THE
EVENING. WEAK SHORTWAVE ENERGY AND UPPER DIVERGENCE WILL ALSO BE
APPROACHING BY LATE IN THE EVENING. THIS ALL POINTS TO INCREASING
CHANCES OF SHOWERS AND THUNDERSTORMS FROM WEST TO EAST THROUGH THE
EVENING. PRECIP MAY BE MORE OF THE SCATTERED VARIETY DURING THE
EVENING...BUT THE MAIN SHOW LOOKS TO ARRIVE AFTER MIDNIGHT FROM THE
SOUTHWEST. AS THE LOW MOVES TOWARDS FAR NORTHEAST IOWA OR SOUTHWEST
WISCONSIN...THE NOSE OF THE LLJ WILL IMPINGE ON CENTRAL AND
NORTHEAST WISCONSIN. OUTSTANDING MOISTURE TRANSPORT WILL ADVECT IN
PWATS GREATER THAN 2 INCHES WHILE STRONG MID-LEVEL FGEN WILL BE
FOCUSED ON THE NOSE OF THE LLJ. ELEVATED INSTABILITY WILL PEAK
DURING THE EVENING HOURS...SO SOME POTENTIAL FOR SEVERE CONVECTION
WITH DAMAGING WIND GUSTS TO REACH CENTRAL WISCONSIN ALONG THE
LEADING EDGE OF ANY THUNDERSTORMS MOVING NORTHEAST OUT OF IOWA. BUT
INSTABILITY RAPIDLY WANES AFTER MIDNIGHT...LEAVING HEAVY RAINFALL AS
THE MAIN HAZARD. ALTHOUGH THERE REMAINS SOME UNCERTAINTY WITH THE
TRACK OF THE SURFACE LOW...THE HEAVIEST RAINFALL SHOULD FALL ON THE
NOSE OF THE LLJ WHICH IS PROJECTED TO PUSH ACROSS CENTRAL AND
NORTHEAST WISCONSIN OVERNIGHT INTO WEDNESDAY MORNING. 1.5 TO 2.5
INCHES OF RAIN WITH LOCALLY HIGHER AMOUNTS ARE POSSIBLE OVER CENTRAL
WISCONSIN BY MORNING.
WEDNESDAY...LOW PRESSURE WILL TRACK TOWARDS THE COAST LINE OF
EAST-CENTRAL OR NORTHEAST WISCONSIN BY 18Z WED. THE HEAVIEST OF
RAIN WILL BE ONGOING ON THE NOSE OF THE LLJ OVER NORTHEAST
WISCONSIN. LOOKING FOR THE SAME MAGNITUDE OF AMOUNTS IN THIS REGION
COMPARED TO CENTRAL WISCONSIN...1.5 TO 2.5 INCHES WITH LOCALLY
HIGHER AMOUNTS. THE HEAVY RAIN WILL PULL OUT WEDNESDAY AFTERNOON AS
NORTHWEST WINDS BEHIND THE SYSTEM DRAWS IN MUCH COLDER AIR INTO
NORTH-CENTRAL WISCONSIN. A WIDE RANGE OF HIGH TEMPERATURES WILL BE
PRESENT TOMORROW...RANGING FROM THE MIDDLE 50S NORTH TO THE LOWER
70S SOUTHEAST.
.LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY
ISSUED AT 245 PM CDT TUE SEP 9 2014
COOLER TEMPERATURE TRENDS AND PCPN CHANCES WILL BE THE FOCUS
DURING THIS PERIOD.
REMAINING SHOWERS FROM THE STRONG WEDNESDAY SYSTEM WILL DEPART TO
THE NORTHEAST BUT SMALL SHOWER CHANCES WILL LINGER INTO THURSDAY OVER
THE NORTH DUE TO CAA INSTABILITY OVER LAKE SUPERIOR. BLUSTERY
NORTH WINDS WILL BRING A FEEL OF FALL TO THE AREA.
HIGH PRESSURE WILL REMAIN SETTLED OVER THE NORTHERN PLAINS
THURSDAY NIGHT WITH SUBTLE CAA CONTINUING. SOME POTENTIAL OF FROST
FRIDAY MORNING OVER THE NORTH BUT WILL DEPEND ON DIMINISHING WINDS
AND CLOUDS. CLOUDS MAY ALREADY BE ON THE INCREASE WITH THE
APPROACH OF A DEEP MID LEVEL TROUGH OR CLOSED UPPER LOW
SYSTEM. THIS SYSTEM WILL BRING A CHANCE OF SHOWERS TO THE AREA
WHICH WILL LINGER INTO SATURDAY MORNING.
COOL HIGH PRESSURE WILL THEN BUILD INTO THE THE GREAT LAKES REGION
FOR THE WEEKEND TO PROVIDE MORE CHANCES OF FROST...AND POSSIBLE
HEADLINES. AGAIN WINDS MAY BE AN ISSUE SINCE THE CENTER OF THE
HIGH SLIDES INTO CENTRAL ILLINOIS SATURDAY NIGHT.
RETURN FLOW WILL BEGIN TO BRING MODERATING WARMER TEMPS INTO THE
AREA SUNDAY FOLLOWED WITH ANOTHER CHANCE OF SHOWERS WITH A
POSSIBLE FRONTAL SYSTEM FOR EARLY NEXT WEEK.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1132 AM CDT TUE SEP 9 2014
AS A STRONG COLD FRONT DROPS SOUTHWARD INTO NORTHERN
WISCONSIN TONIGHT...LOW PRESSURE WILL BE LIFTING NORTHEAST ACROSS
SOUTHWEST TO EAST-CENTRAL WISCONSIN WEDNESDAY MORNING. AHEAD OF
THIS FRONT AND SURFACE LOW...EXPECT CONDITIONS TO DETERIORATE
THROUGH THE NIGHT...STARTING OUT IN NORTH-CENTRAL AND CENTRAL
WISCONSIN THIS EVENING...AND THEN REACHING NORTHEAST WISCONSIN
OVERNIGHT. A LARGE AREA OF SHOWERS AND THUNDERSTORMS SHOULD SURGE
NORTHEAST AHEAD OF LOW OVERNIGHT INTO EARLY WEDNESDAY MORNING WHICH
COULD PRODUCE STRONG GUSTY WINDS...IN ADDITION WIDESPREAD HEAVY
RAIN. LIFR CONDITIONS ARE LIKELY AT RHI AND AUW/CWA AND POSSIBLY
GRB/ATW/MTW OVERNIGHT THROUGH WEDNESDAY MORNING. IMPROVING
CONDITIONS SHOULD OCCUR WEDNESDAY AFTERNOON.
&&
.HYDROLOGY...
ISSUED AT 245 PM CDT TUE SEP 9 2014
WHILE A SOAKING RAIN OF 1.00 TO 1.50 IS EXPECTED FOR
ALL LOCATIONS TONIGHT INTO WEDNESDAY...VERY CHALLENGING FORECAST
WITH DETERMINING THE AXIS OF HEAVIER RAINFALL DUE TO THE TRACK OF
THE SURFACE LOW. ECMWF TRACKS PLACES THE MAX OF 2-3 INCHES OVER
CENTRAL TO NORTHEAST WISCONSIN...NAM MUCH FURTHER NORTH WHILE THE
GEM AND MAV FOCUS OVER THE SOUTH HALF OF THE STATE INCLUDING
BRUSHING PARTS OF EAST CENTRAL WISCONSIN. TO COMPLICATE THE
SITUATION...RADAR TRENDS OVER THE CENTRAL PLAINS SHOWING SOME SPLIT
IN THE RAIN REGIONS. THE SOUTHERN REGION OF HEAVY RAINFALL OVER
SOUTHWEST IOWA IS THE PRIMARY REGION OF CONCERN AND WILL BE THE
FOCUS OF LATER NIGHT HEADLINES. REGARDLESS...THE FLOOD WATCH WILL
CONTINUE FOR THE ENTIRE AREA STARTING LATE THIS EVENING.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH FROM 10 PM CDT THIS EVENING THROUGH WEDNESDAY
EVENING FOR WIZ005-010>013-018>022-030-031-035>040-045-048>050-
073-074.
&&
$$
SHORT TERM.....MPC
LONG TERM......TDH
AVIATION.......MPC
HYDROLOGY......TDH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1055 PM MDT MON SEP 8 2014
.UPDATE...
ISSUED AT 904 PM MDT MON SEP 8 2014
LATEST RETURNS FROM KCYS SHOWS INITIAL BAND OF PRECIPITATION
LIFTING EAST/NORTHEAST THRU CONVERSE AND NRN PLATTE
COUNTIES...WITH THE NEXT BAND LIFTING NE OUT OF NRN COLORADO.
LATEST HRRR SUGGESTS THAT THIS AREA WILL CONTINUE TO EXPAND
NORTHEASTWARD ACROSS MUCH OF THE CWFA DURING THE OVERNIGHT AND
EARLY TUESDAY MORNING HOURS. SO...HAVE BOOSTED POPS ACROSS MANY
AREAS DURING THAT PERIOD GIVEN THE EXPECTED AREAL COVERAGE OF
PRECIPITATION DURING THAT TIME.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 405 PM MDT MON SEP 8 2014
ISOLATED SHOWERS AND THUNDERSTORMS WILL OCCUR ACROSS SOUTHEAST
WYOMING AND THE NEBRASKA PANHANDLE THROUGH THIS EVENING. A FEW
SHOWERS AND THUNDERSTORMS COULD LINGER INTO THE OVERNIGHT MAINLY
NEAR THE COLORADO BORDER. LATE TONIGHT UPPER LEVEL ENERGY AND MID
LEVEL MOISTURE WILL BRING ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS
TO THE SOUTHWEST FORECAST AREA. THIS AREA OF CONVECTION WILL SPREAD
NORTH AND EAST INTO SOUTHEAST WYOMING AND THE NEBRASKA PANHANDLE
TUESDAY AFTERNOON AND EVENING.
THUNDERSTORM CHANCES WILL DECREASE THROUGH TUESDAY EVENING WITH
GENERALLY SHOWERS OVER THE AREA AS THE FIRST OF A SERIES OF COLD
FRONTS MOVES THROUGH THE FORECAST AREA. TEMPERATURES WILL ALREADY
BEGIN TO COOL TUESDAY WITH THE INCREASE CLOUD COVER AND
PRECIPITATION BUT BY WEDNESDAY HIGHS WILL ONLY BE IN THE 50S AND 60S
AS LOW CLOUDS AND UPSLOPE FLOW PUSH ACROSS AREAS ALONG AND EAST OF
THE LARAMIE RANGE. A SECOND PUSH OF COLD AIR WILL COME WEDNESDAY
NIGHT. THE AIR BEHIND THIS FRONT WILL BE COLD ENOUGH THAT SNOW WILL
BE POSSIBLE IN THE MOUNTAINS. ANY ACCUMULATIONS WOULD BE MINIMAL
BASED ON LATEST FORECAST MODELS...BUT THE MODEL TREND HAS BEEN
COLDER AND SLIGHTLY FARTHER SOUTH SO NOT RULING OUT A FEW INCHES OF
SNOW IN THE MOUNTAINS. COULD ALSO SEE SOME SNOW INTO EAST CENTRAL
WYOMING AND THE HIGHER ELEVATIONS OF THE NORTHERN NEBRASKA
PANHANDLE...SUCH AS ALONG THE PINE RIDGE LATE WEDNESDAY NIGHT. AIR
TEMPERATURES ARE NOT EXPECTED TO GO BELOW FREEZING OUTSIDE OF THE
MOUNTAINS WEDNESDAY NIGHT...BUT COLD ENOUGH ALOFT THAT SNOW MAY BE
POSSIBLE. ANY SNOW THAT WOULD FALL WOULD LIKELY MELT ONCE HITTING
THE GROUND.
.LONG TERM...(THURSDAY THROUGH NEXT MONDAY)
ISSUED AT 348 PM MDT MON SEP 8 2014
MAIN FORECAST CONCERN IN THE MEDIUM RANGE WILL BE THE STRONG
AUTUMN-LIKE COLD FRONT DIGGING SOUTH ACROSS THE HIGH PLAINS AND
FRONT RANGE ON THURSDAY. THE UPPER LEVEL TROUGH AND BULK OF THE
COLDER AIR WILL ARRIVE ACROSS SOUTHEAST WYOMING AND WESTERN
NEBRASKA THURSDAY NIGHT. THE 12Z GFS IS STILL SLIGHTLY WARMER THAN
THE ECMWF AND GEM MODELS...BUT IS STARTING TO TREND COOLER
COMPARED TO PREVIOUS RUNS. UPSLOPE FLOW WILL DEVELOP DURING THE
DAY AND BECOME STRONGER INTO THURSDAY NIGHT WITH EAST TO NORTHEAST
WINDS BETWEEN 15 TO 25 MPH LIKELY. PRECIPITATION IS EXPECTED TO
DEVELOP BEHIND THE FRONT AS UPSLOPE FLOW BECOMES STRONGER.
ENHANCEMENT IN PRECIP RATES IS EXPECTED AS A STRONG 110 KNOT JET
SLIDES SOUTHWARD ACROSS EAST CENTRAL WYOMING AND THE DAKOTAS LATE
ON THURSDAY. IN ADDITION...ANY SURFACE INSTABILITY WILL FURTHER
ENHANCE PRECIP RATES AS FROPA OCCURS. CONTINUED TO INCREASE POP UP
TO 60 PERCENT ACROSS THE HIGH PLAINS...MAINLY FROM THE NORTHERN
LARAMIE RANGE EASTWARD ACROSS THE PINE RIDGE WHICH WILL LIKELY SEE
THE HIGHEST PRECIP RATES DUE TO SLIGHTLY BETTER DYNAMIC FORCING.
INCREASED POP BETWEEN 40 TO 55 PERCENT ALONG THE I80 CORRIDOR FOR
NOW...MAINLY THURSDAY NIGHT. THE MAIN QUESTION WILL BE WHEN/IF THE
RAIN CHANGES MIXES WITH OR CHANGES TO SNOW. THE FIRST SNOWFALL OF
THE SEASON IS APPEARING MORE LIKELY AS TIME GOES ON ACROSS THE
HIGH PLAINS SINCE MOST MODELS CONTINUE TO TREND COLDER. EXPECT
SNOWLEVELS TO LOWER BETWEEN 4000 TO 5500 FEET ACROSS MOST OF
SOUTHEAST WYOMING AND WESTERN NEBRASKA BY EARLY FRIDAY
MORNING...WITH RAIN CHANGING TO SNOW. STILL TOO EARLY TO TELL IF
SNOW ACCUMULATIONS WILL OCCUR ON GRASSY SURFACES SINCE SNOWFALL
RATES WILL HAVE TO OVERCOME THE WARM GROUND...AND THAT IS NOT
CLEAR AT THIS TIME. WENT WITH A 4O TO 50 PERCENT CHANCE OF SNOW
ACROSS MOST OF THE AREA...WITH THE EXCEPTION OF WESTERN CARBON
COUNTY AND THE FAR SOUTHEASTERN ZONES INCLUDING SIDNEY AND
BRIDGEPORT. TEMPERATURES WILL MUCH MUCH COLDER THAN NORMAL ON
THURSDAY WITH HIGHS IN THE 40S AND 50S. SOME LOCATIONS FURTHER
NORTH MAY NOT EVEN HIT 40 DURING THE DAY AS PRECIPITATION DEVELOPS
OVER THE AREA AND MOVES SOUTH. MAY SEE THE FIRST WIDESPREAD HARD
FREEZE ACROSS MOST OF SOUTHEAST WYOMING...AND PORTIONS OF THE
NORTHERN NEBRASKA PANHANDLE BY FRIDAY MORNING WITH LOWS BETWEEN 26
TO 32 DEGREES.
AFTER ANOTHER CHILLY DAY ON FRIDAY WITH HIGHS BARELY REACHING 50
DEGREES...A SLOW WARMING AND DRYING TREND IS EXPECTED FOR THIS
WEEKEND. ALL MODELS SHOW A BROAD RIDGE ALOFT SLOWLY BUILDING INTO
THE NORTHERN AND CENTRAL ROCKY MOUNTAIN REGION. HIGHS IN THE LOW
TO MID 70S ARE EXPECTED THIS WEEKEND ACROSS MOST OF THE AREA WITH
POP BELOW 5 PERCENT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY EVENING)
ISSUED AT 1048 PM MDT MON SEP 8 2014
SEVERAL BANDS OF SHOWERS ALONG WITH A FEW EMBEDDED THUNDERSTORMS
WILL PASS OVER MANY OF THE AREA TERMINALS THRU THE OVERNIGHT HOURS
AND DURING THE DAY ON TUESDAY. GIVEN UNCERTAINTY IN TIMING AND
LOCATION DETAILS...HAVE INCLUDED VCTS DURING THE AFTERNOON HOURS.
EXPECT GENERALLY VFR CONDITIONS TO PREVAIL...BUT SHOULD SEE
CONDITIONS DETERIORATE TO MVFR AT KCDR AFTER 18Z AND AT ALL
AIRFIELDS AFTER 02Z.
&&
.FIRE WEATHER...
ISSUED AT 340 PM MDT MON SEP 8 2014
ISOLATED SHOWERS AND THUNDERSTORM ACROSS SOUTHEAST WYOMING AND INTO
THE NEBRASKA PANHANDLE THIS AFTERNOON AND EVENING. A BATCH OF
SHOWERS AND THUNDERSTORMS WILL MOVE INTO SOUTH CENTRAL WYOMING
LATE TONIGHT AND THEN SPREAD EAST INTO THE PLAINS TUESDAY AFTERNOON.
TURNING COOLER TUESDAY AND THEN COLDER WEDNESDAY AND THURSDAY...
ESPECIALLY FOR LOCATIONS EAST OF THE LARAMIE RANGE. IT WILL BE
COLD ENOUGH THAT SNOW WILL BE POSSIBLE INTO THE MOUNTAINS BY
WEDNESDAY NIGHT AND POTENTIALLY INTO EAST CENTRAL WYOMING
AND HIGHER ELEVATIONS OF THE NEBRASKA PANHANDLE INTO THURSDAY
MORNING.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...HAHN
SHORT TERM...SML
LONG TERM...TJT
AVIATION...HAHN
FIRE WEATHER...SML
AREA FORECAST DISCUSSION
NWS ALBANY NY
445 AM EDT THU SEP 11 2014
.SYNOPSIS...
LOW PRESSURE IN EASTERN CANADA WILL DRIVE A COLD FRONT ACROSS THE
REGION LATER TODAY. AHEAD OF THIS FRONT WILL BE SCATTERED SHOWERS
AND PERHAPS A THUNDERSTORM...MAINLY SOUTH OF ALBANY. BEHIND THIS
FRONT WILL COME THE COOLEST AIR MASS SINCE LATE MAY BY FRIDAY. A
DISTURBANCE MIGHT BRING A ROUND OF SHOWERS ON SATURDAY FOLLOWED BY
MORE COOL DRY WEATHER SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 445 AM EDT...A RATHER POTENT LOW PRESSURE AREA WAS JUST NORTH
OF LAKE HURON. THIS STORM HAS A WINTRY LOOK TO IT IN THAT IT HAS A
VERY WELL DEFINED AREA OF DEFORMATION RAIN ON ITS NORTHWEST SIDE...A
COLD RAIN AT THAT...WITH POSSIBLY A LITTLE WET SNOW MIXING TO THE
SOUTH OF JAMES IN CANADA.
CLOSER TO HOME...RAIN SHOWERS WERE WORKING INTO OUR WESTERN AREAS TO
THE WEST OF THE HUDSON RIVER VALLEY. SO FAR THERE HAS BEEN NO
INDICATIONS OF THUNDERSTORMS WITH THIS FIRST LINE OF SHOWERS. THE
LATEST RUC13 INDICATE LITTLE OR NO INSTABILITY SO WE KEPT ANY
MENTION OF THUNDER OUT OF THE FORECAST THROUGH EARLY MORNING.
TEMPERATURES WERE QUITE MILD DUE TO AN INCREASE IN CLOUDS...AND A
PERSISTENT SOUTHERLY BREEZE ON THE WARM SIDE OF THE LOW
PRESSURE...HOLDING MAINLY IN THE 60S.
A COLD FRONT ASSOCIATED WITH THE LOW PRESSURE WAS WORKING INTO
WESTERN NY STATE. THIS FRONT WILL MOVE STEADILY ALONG AND WORK INTO
THE SOUTHERN ADIRONDACKS AND THE MOHAWK VALLEY EARLY THIS
AFTERNOON...THE CAPITAL REGION AND SURROUNDING AREAS LATE
AFTERNOON...AND THE MID HUDSON VALLEY AND NORTHWESTERN CONNECTICUT
BY EARLY EVENING.
MORE LINES OF SHOWERS CAN BE EXPECTED TODAY. DUE TO VERY LIMITED
INSTABILITY WE ONLY MENTION A SLIGHT CHANCE OF THUNDERSTORM FROM THE
CAPITAL REGION NORTHWARD. FURTHER SOUTH...WITH A LITTLE MORE
INSTABILITY...WE DID MENTION A CHANCE OF THUNDERSTORMS. IT IS
REMOTELY POSSIBLE THAT ANY THUNDERSTORM IN THIS AREA COULD CONTAIN
SOME GUSTY WINDS AS THE OVERALL WIND FIELD (BULK SHEAR) INCREASES TO
ABOUT 35-40KTS. HOWEVER...THE THREAT APPEARED LOW ENOUGH NOT TO
MENTION IN THE GRIDS OR CERTAINLY ENHANCED WORDING AT THIS TIME.
PWAT VALUES LOOK TO INCREASE TO ABOUT 2 INCHES...BUT THIS LOOKS TO
HAPPEN THIS MORNING. THE H20 WATER VAPOR LOOP ALREADY INDICATED A
MID LEVEL DRY PUNCH QUICKLY WORKING INTO WESTERN NEW YORK STATE.
THIS DRY PUNCH WILL ALLOW PWATS TO DROP QUICKLY THIS
AFTERNOON...EVEN AHEAD OF THE FRONT. THEREFORE THE BEST FORCING
(WHICH IS GOING TO WELL NORTH)...WILL NOT LINE UP WITH THE BEST
PWATS AND PASSAGE OF THE COLD FRONT.
THERE WILL BE PLENTY OF CLOUDS TODAY WITH PERHAPS A FEW BREAKS OF
AFTERNOON SUNSHINE. EVEN SO...TEMPERATURES COULD SPIKE A LITTLE
AHEAD OF THE FRONT...AS THEY WERE ACTUALLY IN THE LOWER 70S IN
SECTIONS OF CENTRAL NEW YORK! WE EXPECT HIGHS NEAR 80 IN THE MID
HUDSON VALLEY AND LOWER LITCHFIELD COUNTY...UPPER 70S AROUND ALBANY.
FURTHER NORTH AND WEST WHERE THE COLD FRONT WILL BE FIRST TO COME
THROUGH...HIGH TEMPERATURES WILL BE HELD TO BETWEEN THE UPPER 60S TO
MID 70S.
A GUSTY SOUTH WIND PREVAIL TODAY 10 TO 20 MPH...SHIFTING TO THE WEST
BY LATE IN THE DAY ONCE THE COLD FRONT MOVES THROUGH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
THE COLD FRONT WILL BE FINISHING ITS SWEEP THROUGH OUR AREA THIS
EVENING TAKING ANY LEFTOVER SHOWERS WITH IT.
THEN...A COOL CANADIAN AIR MASS WILL BE USHERED IN TONIGHT ON
SOMEWHAT GUSTY NORTH OR NORTHWEST WINDS. THE SKY WILL CLEAR AND
TEMPERATURES WILL DIP DOWN TO AROUND 50 FROM ALBANY SOUTH AND EAST.
FURTHER NORTHWEST AND WEST...THEY WILL DIVE INTO THE 40S...AND EVEN
TOUCH THE UPPER 30S ACROSS OUR ADIRONDACKS.
FRIDAY LOOKS TO FEATURE A GOOD DEAL OF SUNSHINE (MIXING WITH FAIR
WEATHER STRATO-CUMULUS) AND TEMPERATURES BELOW NORMAL. H850
TEMPERATURES LOOK TO DROP TO BETWEEN +5C NORTHWEST TO +9C SOUTHEAST
ACROSS OUR REGION. THIS WILL TRANSLATE TO HIGH TEMPERATURES MAINLY
IN THE 60S THROUGH OUR REGION...PERHAPS TOUCHING 70 FROM
POUGHKEEPSIE...BUT ONLY 50S ACROSS THE ELEVATED TERRAIN NORTH OF
ALBANY...MAKING IT FEEL AUTUMNAL.
HIGH PRESSURE WILL CREST NORTH OF THE REGION EARLY FRIDAY NIGHT
BEFORE RETREATING TO THE CANADIAN MARITIMES. A COOL NIGHT IS IN
STORE BUT NOT AS COOL AS WOULD HAVE BEEN. WHILE THE NIGHT WILL START
CLEAR...CLOUDS SHOULD INCREASE DUE TO WARM AIR ADVECTION AS A POTENT
DISTURBANCE APPROACHES FROM THE OHIO VALLEY. OVERNIGHT LOWS WILL
RANGE FROM THE UPPER 40S SOUTHEAST OF ALBANY...DOWN TO THE UPPER 30S
ACROSS THE ADIRONDACKS. IF IT WERE TO GET ANY COLDER THERE...SOME
FROST WOULD BE POSSIBLE. WE WILL MONITOR THAT POTENTIAL BUT FOR
NOW...WE ARE FORECASTING TEMPERATURES TO REMAIN JUST ABOVE THE FROST
THRESHOLD.
THEN ON SATURDAY...AS THE AFOREMENTIONED DISTURBANCE APPROACH...IT
LOOKS AS OF SURFACE LOW PRESSURE WILL FORM AT THE TRIPLE POINT OF
THE WARM FRONT/COLD FRONT INTERFACE TO OUR SOUTHEAST. AT THIS POINT
SHOWERS APPEARS TO BE A GOOD BET. IF SURFACE LOW PRESSURE DEVELOPS
EVEN QUICKER...WE WOULD BE LOOKING AT A STEADY RAIN. FOR NOW...WILL
CALL IT SHOWERS...BUT EITHER WAY...SATURDAY LOOKS LIKE A
CLOUDY...DAMP DAY WITH HIGHS RANGING ONLY FROM THE MID 50S NORTHWEST
TO UPPER 60S SOUTHEAST OF ALBANY.
THE DISTURBANCE LOOKS TO MOVE QUICKLY EAST SATURDAY NIGHT...FOLLOWED
BY PARTIAL CLEAR AND ANOTHER CANADIAN HIGH PRESSURE BRINGING A
RE-NEWED SHOT OF COOL BUT DRY TO CLOSE OUT THE WEEKEND.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
THE LONG TERM PORTION OF THE FORECAST WILL FEATURE A BROAD UPPER
TROUGH ACROSS THE EASTERN 2/3RDS OF NOAM. THIS WILL KEEP
TEMPERATURES A BIT BELOW NORMAL ALONG WITH NEAR TO BELOW NORMAL
PRECIPITATION. THE NEXT APPRECIABLE CHANCE FOR WET WEATHER IS LATE
MONDAY NIGHT INTO TUESDAY AS THE NEXT PV ANOMALY IS PROGGED TO TRACK
ACROSS THE GREAT LAKES REGION AND NORTHEAST CONUS. QPF/S FROM THE
GLOBAL MODELS DIFFER AS THE GFS IS THE MOST AGGRESSIVE /LESS QPF/
WITH TRACK OF THIS WAVE. MEANWHILE THE ECMWF CONTINUES TO SUGGEST A
COASTAL WAVE DEVELOPMENT WHICH SLOWS DOWN THE FORWARD PROGRESS AND
KEEPS THE PRECIP LINGER LONGER /AND HIGHER QPF/. THE GGEM IS
FURTHER SOUTH WITH LIGHTER AMOUNTS AS MAIN WAVE MOVES OFF THE
CAROLINA/VIRGINIA COAST. OTHERWISE...SURFACE HIGH PRESSURE WILL BE
THE MAIN FEATURE. THE H850 MEAN TEMPERATURES ARE EXPECTED TO HOVER
INTO THE MIDDLE SINGLE DIGITS WHICH WILL RESULT IN MAINLY 60S FOR
VALLEY LOCATIONS AND OVERNIGHT LOWS INTO THE 40S.
&&
.AVIATION /08Z THURSDAY THROUGH MONDAY/...
CLOUDS CONTINUE TO INCREASE...THICKEN AND LOWER ACROSS THE REGION
WITH LATEST VIEW OF THE 11U-3.9U SATELLITE IMAGERY REVEALING THE
EXPANDING LOW LEVEL STRATUS /MVFR CIGS/ FROM THE WEST-SOUTHWEST
DIRECTION ADVECTING NORTHWARD. WE WILL THEREFORE PLACE AT LEAST
MVFR FLIGHT RESTRICTIONS INTO THE TAF/S OVERNIGHT. AS FOR SHOWER
POTENTIAL...UPSTREAM REGIONAL RADAR MOSAIC SHOWS THE LEADING EDGE OF
THE PRECIP IS ERODING DUE TO THE DOWNSTREAM DRY AIRMASS IN PLACE.
PER THE LATEST HRRR REFLECTIVITY...EXPECTATIONS ARE FOR THE SHOWER
POTENTIAL TO INCREASE TOWARD SUNRISE AS THESE THOUGHTS ARE REFLECTED
IN THE TAF/S.
THE BEST TIME PERIOD FOR WET WEATHER APPEARS TO BE AROUND SUNRISE
AND INTO THE MID MORNING HOURS ASSOCIATED WITH THE FRONTAL PASSAGE.
AFTER FROPA...WINDS WILL SHIFT TOWARD THE WEST-NORTHWEST WITH A
DRIER MID LEVELS. HOWEVER...LOWER LEVEL MOISTURE MAY LINGER AS WE
WILL KEEP CIGS ON THE BORDER OF MVFR/VFR.
WINDS WILL BE SOUTHERLY TO SOUTHEASTERLY AROUND 3-7
KT...BECOMING SOUTH AND INCREASING TO 5-10 KT BY 12Z THURSDAY. WINDS
WILL SHIFT TO THE WEST-NORTHWEST AROUND 10KTS WITH SOME HIGHER GUSTS
TOWARD 20KTS POSSIBLE BY AFTERNOON.
OUTLOOK...
THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
SUNDAY TO MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
A COLD FRONT WILL CROSS THE REGION THIS AFTERNOON...BRINGING SOME
SHOWERS AND PERHAPS A THUNDERSTORM...MAINLY SOUTH OF ALBANY.
RAINFALL AMOUNTS WITH SHOWERS LOOK TO BE UP TO HALF AN INCH IN OUR
NORTHWESTERN ZONES...AROUND A QUARTER INCH LOCALLY IN THE CAPITAL
REGION...LESS THAN THAT FURTHER SOUTH.
A SOUTH WIND WILL AVERAGE 10 TO 20 MPH TODAY...SHIFTING TO THE
NORTHWEST BEHIND THE COLD FRONT.
RH LEVELS WILL REMAIN ELEVATED THIS AFTERNOON...ONLY DROPPING INTO
THE 60S.
TONIGHT ALL THE SHOWERS WILL MOVE EAST FOLLOWED BY PARTIAL CLEARING.
A NORTHWEST BREEZE MIGHT BE ENOUGH TO MITIGATE THE FORMATION OF MOST
FOG.
FRIDAY WILL BE A DRY DAY WITH TEMPERATURES A BIT BELOW NORMAL. RH
VALUES BY AFTERNOON WILL BE IN THE 35-45 PERCENT RANGE. THE SURFACE
WIND WILL BE NORTH TO NORTHWEST 5-15 MPH.
THE NEXT CHANCE OF SHOWERS WILL BE ON SATURDAY.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE EXPECTED THE NEXT FIVE DAYS
ENDING MONDAY.
SHOWERS AND ANY THUNDERSTORMS TODAY WILL PRODUCE ONLY ABOUT HALF AN
INCH OF AVERAGE BASIN RAINFALL IN OUR NORTHERN AREAS...ABOUT A
QUARTER INCH OR LESS ALBANY SOUTHWARD.
THIS RAIN WILL NOT INFLUENCE ANY OF OUR MAIN STEM RIVERS THROUGH OUT
THE REGION.
ANY THUNDERSTORM COULD CONTAIN LOCALLY HEAVY RAINFALL...WITH AMOUNTS
CLOSER TO AN INCH...JUST ENOUGH TO PRODUCE SOME PONDING OF WATER IN
A FEW SPOTS.
DRY WEATHER WILL RETURN TONIGHT AFTER A POSSIBLE LEFTOVER EVENING
SHOWERS. IT WILL BE DRY FRIDAY...BUT THERE IS A CHANCE OF SHOWERS ON
SATURDAY WITH ANOTHER DISTURBANCE. THEN...DRY WEATHER RETURNS SUNDAY
INTO EARLY NEXT WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...BGM
AVIATION...BGM
FIRE WEATHER...HWJIV/WASULA
HYDROLOGY...HWJIV/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
130 AM EDT THU SEP 11 2014
.SYNOPSIS...
LOW PRESSURE WILL MOVE INTO SOUTHEASTERN CANADA
OVERNIGHT...AS A COLD FRONT APPROACHES THE REGION. THIS COLD FRONT
WILL BRING SHOWERS AND ISOLATED THUNDERSTORMS TO SOME LOCATIONS
THIS MORNING INTO THE AFTERNOON. HIGH PRESSURE WILL BRING COOL
AND DRY WEATHER BACK INTO THE REGION THURSDAY NIGHT INTO EARLY
SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 100 AM EDT...CLOUDS CONTINUE TO SLOWLY GATHER OVER MOST OF THE
REGION...WHILE STILL THIN AND ONLY PARTIAL IN SOUTHERN AREAS. RADARS
INDICATED A FEW POSSIBLE SPRINKLES OVER NORTHERN AREAS...WHILE THE
MORE SIGNIFICANT MEASURABLE SHOWERS HAVE YET TO WORK INTO OUR
NORTHWESTERN AREAS.
FOR THIS UPDATE...ONLY SLIGHT MODIFICATION OF THE HOURLY POPS AS
MOST OF THE NEWEST GUIDANCE INDICATED SHOWERS WILL BE WORKING INTO
THE CAPITAL REGION BY SUNRISE...TO INCREASED POPS A LITTLE.
OTHERWISE ONLY VERY MINOR TINKERING OF THE REMAINDER OF THE HOURLY
GRIDS.
TEMPERATURES WILL BE MILDER THAN THE PREVIOUS FEW NIGHTS DUE TO
THE LOW LEVEL WARM ADVECTION...LIGHT SOUTHERLY BREEZE...AND
INCREASING CLOUDS. LOWS WILL GENERALLY BE IN THE MID AND U50S OVER
THE MTNS...AND U50S TO L60S IN THE VALLEYS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY/...TOMORROW...THE
TIMING/SPEED OF THE COLD FRONT HAS INCREASED ACCORDING TO THE LATEST
NAM/CAN GGEM/ECMWF/GFS FOR AN EARLIER ONSET OF THE SHOWERS AND ISOLD
THUNDERSTORMS SOUTH AND EAST OF THE CAPITAL REGION. THE THREAT FOR
THUNDERSTORMS HAVE GREATLY DIMINISHED NORTH AND WEST OF THE CAPITAL
REGION DUE TO LIMITED HEATING AHEAD OF THE FRONT...AND HENCE A LACK
OF INSTABILITY. THE BEST L0W-LEVEL CONVERGENCE IS WITH THE
FRONT...AND S/SW LLJ AT H850 INCREASES TO 40-50 KTS OR SO AROUND
12Z...AND CONTINUES AT 30-45 KTS IN THE AFTERNOON. POPS WERE
INCREASED TO LIKELY VALUES IN THE LATE MORNING INTO THE
AFTERNOON...ESPECIALLY FROM THE
BERKSHIRES...CAPITAL REGION...AND NRN CATSKILLS...NORTH AND WEST.
SOME OROGRAPHIC ENHANCEMENT IS POSSIBLE OVER THE SRN GREENS...AND
WRN DACKS...AS THE BOUNDARY LAYER WINDS VEER TO THE WEST BY
LUNCHTIME. MUCH OF THE HYDRO SERVICE AREA NEEDS SOME RAINFALL. THE
CONVERGENCE WEAKENS A BIT SOUTH OF THE CAPITAL REGION...BUT AN
ISOLD THUNDERSTORMS ARE POSSIBLE WITH SBCAPE VALUES OF 200-500 J/KG.
A THREAT WAS CONTINUED THERE INTO THE EARLY EVENING. PWATS BRIEFLY
SURGE TO 1.5-2.0" OR SO AHEAD OF THE FRONT...BUT THIS IS FOR A
SHORT DURATION...SO LOCALLY HEAVY RAINFALL WAS REMOVED FROM THE
GRIDS AT THIS TIME. HIGHS WILL GENERALLY BE IN THE U70S TO L80S
FROM THE CAPITAL REGION...AND MOHAWK VALLEY SOUTH AND EAST...AND
U60S T0 L70S NORTH AND WEST...EXCEPT MID OR UPPER 70S IN THE UPPER
HUDSON VALLEY...AND PARTS OF THE CT RIVER VALLEY.
THU NIGHT...THE FRONT SLIDES SOUTH AND EAST OF THE FCST AREA WITH
THE ISOLD-SCT SHOWERS ENDING IN THE EARLY EVENING. STRONG LOW-
LEVEL COLD ADVECTION OCCURS IN THE WAKE OF THE FRONT. H850 TEMPS
FALL TO -4C TO -10C FROM ALY NORTH AND WEST...AND -10C TO -14C TO
THE SOUTH AND EAST. THE SKIES WILL GRADUALLY CLEAR FROM NW TO
SE...AND A N TO NW BREEZE OF 5-15 MPH WILL KEEP IT COOL. LOWS WILL
BE IN THE U40S TO L50S SOUTH AND EAST OF THE CAPITAL DISTRICT /FEW
MD 50S IN NW CT AND THE MID HUDSON VALLEY/...AND LOWER TO MID 40S
NORTH AND WEST...AND EVEN A FEW U30S OVER THE SRN DACKS.
FRI-FRI NIGHT...FAIR...COOL AND DRY WEATHER RETURNS TO THE FCST
AREA...AS A LARGE DOME OF CANADIAN HIGH PRESSURE RIDGES IN FROM
S-CNTRL CANADA...THE NRN PLAINS...AND GREAT LAKES REGION. MAX
TEMPS WILL RUN ABOUT 5-10 DEGREES BELOW NORMAL WITH HIGHS MAINLY
IN THE 60S. SOME U50S ARE POSSIBLE OVER THE SRN GREENS...SRN
DACKS...AND ERN CATSKILLS. A FEW L70S ARE POSSIBLE OVER THE MID
HUDSON VALLEY. A COOL NIGHT IS EXPECTED WITH PERHAPS SOME PATCHY
FROST OVER THE SRN DACKS WITH TEMPS IN THE MID AND U30S. EXPECT
LOWER TO M40S OVER A LARGE PORTION OF THE REST OF THE AREA. THE
METMOS MINS WERE FAVORED HERE.
SATURDAY...A SHORT-WAVE TROUGH...AND A WEAK COLD FRONT MAY
INCREASE THE CLOUDS WITH A CHC OF SHOWERS IN THE AFTERNOON. TEMPS
WILL BE A LITTLE MILDER THAN FRI WITH HIGHS IN THE 60S TO L70S.
THE GFS AND ECMWF/CAN GGEM CONTINUE TO DISAGREE ON THE AMOUNT OF
MOISTURE ASSOCIATED WITH THE SHORT-WAVE...WITH THE INTERNATIONAL
GUIDANCE WETTER THAN THE GFS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THE LONG TERM PERIOD WILL BE CHARACTERIZED BY MAINLY DRY CONDITIONS
AND HIGH PRESSURE EXCEPT FOR TWO WEAK DISTURBANCES PRODUCING
SCATTERED SHOWERS ACROSS THE REGION SATURDAY NIGHT AND MONDAY NIGHT
INTO TUESDAY.
AT THE START OF THE LONG TERM PERIOD...A WEAK UPPER-LEVEL SHORTWAVE
TROUGH WILL BE PROGRESSING ACROSS THE REGION SATURDAY NIGHT WITH
LINGERING SHOWERS SATURDAY NIGHT ACROSS THE REGION. THESE SHOWERS
ARE EXPECTED TO CLEAR THE REGION BY DAYBREAK SUNDAY AS HIGH PRESSURE
BUILDS ACROSS THE REGION FOR THE REMAINDER OF THE WEEKEND WITH
PARTLY CLOUDY SKIES AND DRY WEATHER.
THIS AREA OF HIGH PRESSURE WILL MOVE ACROSS THE REGION MONDAY AS
ANOTHER WEAK SHORTWAVE TROUGH/CLIPPER-TYPE SYSTEM APPROACHES FROM
THE GREAT LAKES REGION MONDAY NIGHT. MOISTURE LOOKS TO BE LIMITED
WITH THIS FEATURE BUT ENOUGH FORCING SHOULD BE PRESENT TO PROMOTE
ISOLATED TO SCATTERED SHOWERS ACROSS THE REGION MONDAY NIGHT INTO
TUESDAY. HIGH PRESSURE WILL BUILD ACROSS THE REGION THROUGH THE
REMAINDER OF THE LONG TERM PERIOD WITH DRY CONDITIONS AND PARTLY
CLOUDY SKIES.
HIGH TEMPERATURES THROUGHOUT THE LONG TERM PERIOD WILL GENERALLY
RANGE FROM THE UPPER 50S ACROSS THE HIGHER TERRAIN TO NEAR 70 IN
VALLEY LOCATIONS. LOW TEMPERATURES WILL GENERALLY RANGE FROM THE LOW
40S TO NEAR 50...WITH UPPER 30S POSSIBLE ACROSS THE SOUTHERN
ADIRONDACKS SUNDAY NIGHT.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
CLOUDS CONTINUE TO INCREASE...THICKEN AND LOWER ACROSS THE REGION
WITH LATEST VIEW OF THE 11U-3.9U SATELLITE IMAGERY REVEALING THE
EXPANDING LOW LEVEL STRATUS /MVFR CIGS/ FROM THE WEST-SOUTHWEST
DIRECTION ADVECTING NORTHWARD. WE WILL THEREFORE PLACE AT LEAST
MVFR FLIGHT RESTRICTIONS INTO THE TAF/S OVERNIGHT. AS FOR SHOWER
POTENTIAL...UPSTREAM REGIONAL RADAR MOSAIC SHOWS THE LEADING EDGE OF
THE PRECIP IS ERODING DUE TO THE DOWNSTREAM DRY AIRMASS IN PLACE.
PER THE LATEST HRRR REFLECTIVITY...EXPECTATIONS ARE FOR THE SHOWER
POTENTIAL TO INCREASE TOWARD SUNRISE AS THESE THOUGHTS ARE REFLECTED
IN THE TAF/S.
THE BEST TIME PERIOD FOR WET WEATHER APPEARS TO BE AROUND SUNRISE
AND INTO THE MID MORNING HOURS ASSOCIATED WITH THE FRONTAL PASSAGE.
AFTER FROPA...WINDS WILL SHIFT TOWARD THE WEST-NORTHWEST WITH A
DRIER MID LEVELS. HOWEVER...LOWER LEVEL MOISTURE MAY LINGER AS WE
WILL KEEP CIGS ON THE BORDER OF MVFR/VFR.
WINDS WILL BE SOUTHERLY TO SOUTHEASTERLY AROUND 3-7
KT...BECOMING SOUTH AND INCREASING TO 5-10 KT BY 12Z THURSDAY. WINDS
WILL SHIFT TO THE WEST-NORTHWEST AROUND 10KTS WITH SOME HIGHER GUSTS
TOWARD 20KTS POSSIBLE BY AFTERNOON.
OUTLOOK...
THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
SUNDAY TO MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
LOW PRESSURE WILL MOVE INTO SOUTHEASTERN CANADA
TONIGHT...AS A COLD FRONT APPROACHES THE REGION. THIS COLD FRONT
WILL BRING SHOWERS AND ISOLATED THUNDERSTORMS TO SOME LOCATIONS
TOMORROW MORNING INTO THE AFTERNOON. HIGH PRESSURE WILL BRING COOL
AND DRY WEATHER BACK INTO THE REGION THURSDAY NIGHT INTO EARLY
SATURDAY.
THE RH VALUES WILL INCREASE TO 90 TO 100 PERCENT TONIGHT...THEN
LOWER TO 50 TO 70 PERCENT TOMORROW AFTERNOON IN THE SHOWERS.
EXPECT A NEAR FULL RECOVERY TO CLOSE TO 100 PERCENT FRIDAY MORNING.
TOTAL RAINFALL AMOUNTS MAY RANGE FROM TWO TENTHS TO ONE HALF AN
INCH FROM THE FRONT TOMORROW...WITH A FEW LOCALLY HIGHER AMOUNTS.
THE WINDS WILL BE FROM THE SOUTH AT 10 MPH OR LESS TONIGHT...THEN
INCREASE FROM THE SOUTH/SOUTHWEST AND SHIFT TO TO THE WEST AT 10
TO 20 MPH WITH A FEW GUSTS 30 TO 35 MPH DURING THE MID TO LATE
AFTERNOON WITH THE FRONTAL PASSAGE. THE WINDS WILL VEER TO THE
NORTHWEST OR NORTH AT 5 TO 10 MPH THU NIGHT.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE EXPECTED THE NEXT FIVE DAYS
ENDING MONDAY.
THE NEXT CHANCE OF SHOWERS AND ISOLD THUNDERSTORMS WILL BE
TONIGHT THROUGH TOMORROW ASSOCIATED WITH A COLD FRONT PASSING
THROUGH. AVERAGE BASIN RAINFALL LOOKS TO BE WELL UNDER AN INCH.
HOWEVER...ANY THUNDERSTORM COULD CONTAIN HEAVY RAINFALL WITH
LOCALIZED RAINFALL OF GREATER THAN A HALF AN INCH POSSIBLE. MOST
LOCATIONS WILL GET TWO TENTHS TO LESS THAN A HALF AN INCH OF
RAINFALL.
PONDING OF WATER ON ROADS AND OTHER LOW LYING AREAS MAY OCCUR. AT
THIS TIME...LITTLE OR NO RISES ARE EXPECTED ON MAIN STEM RIVERS.
DRY WEATHER RETURNS ON FRIDAY BUT THERE IS A CHANCE OF SHOWERS ON
SATURDAY WITH ANOTHER DISTURBANCE...AND DRY WEATHER RETURNS SUNDAY
INTO EARLY NEXT WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV/WASULA
NEAR TERM...HWJIV/NAS/WASULA
SHORT TERM...WASULA
LONG TERM...IRL
AVIATION...BGM
FIRE WEATHER...HWJIV/WASULA
HYDROLOGY...HWJIV/WASULA
WWW.WEATHER.GOV/ALBANY
AREA FORECAST DISCUSSION
NWS MIAMI FL
450 AM EDT THU SEP 11 2014
.DISCUSSION...
AN AREA OF LOW PRESSURE NEAR THE NORTHWEST BAHAMAS WILL DOMINATE
THE WEATHER DISCUSSION OVER THE NEXT COUPLE DAYS. MODELS ARE IN
GOOD AGREEMENT THAT THIS WEAK SYSTEM WILL MOVE SLOWLY WESTWARD
ACROSS THE NORTHWEST BAHAMAS AND THEN ACROSS SOUTH FLORIDA ON
FRIDAY. CONDITIONS ARE FORECAST TO BECOME UNFAVORABLE OVER THE LOW
TODAY AS SHEAR INCREASES. HOWEVER...THERE IS STILL A SLIGHT CHANCE
THAT THE SYSTEM MAY DEVELOP BEFORE MOVING INTO SOUTH FLORIDA...AND
THEN A MEDIUM CHANCE AFTER IT MOVES INTO THE GULF OF MEXICO OVER
THE WEEKEND. REGARDLESS OF DEVELOPMENT...THE MAIN IMPACT FOR
SOUTH FLORIDA WILL LIKELY BE LOCALLY HEAVY RAINFALL.
TODAY...THE WIND FIELD OVER/NEAR THE LOW IS LIGHT...AND WINDS ARE
FORECAST TO BE VERY LIGHT ACROSS THE REGION TODAY. A LIGHT
NORTHEASTERLY FLOW MAY BRIEFLY DEVELOP BEFORE SEA BREEZE
BOUNDARIES BECOME DOMINANT. STORM MOTION IS FORECAST TO BE
RELATIVELY SLOW TODAY...AND LOCALLY HEAVY RAINFALL IS POSSIBLE.
PONDING IN POORLY DRAINED AREAS AND LOCALIZED STREET FLOODING ARE
THE MAIN THREATS. RAIN CHANCES ARE 50-70% ACROSS THE
REGION. THE LATEST HRRR RUN SHOWS PRETTY HIGH COVERAGE OF RAIN
ACROSS THE REGION. HIGHS ARE FORECAST TO BE IN THE UPPER 80S TO
AROUND 90 DEGREES.
TONIGHT...THE WEAK AREA OF LOW PRESSURE WILL MOVE CLOSER TO THE
EAST COAST...IN THE VICINITY OF PALM BEACH COUNTY COAST BY
DAYBREAK. SCATTERED SHOWERS AND A FEW EMBEDDED STORMS ARE
FORECAST FOR THE EAST COAST METRO AREAS OVERNIGHT.
FRIDAY...THE AREA OF LOW PRESSURE IS FORECAST TO MOVE SLOWLY
ACROSS THE REGION...AND SHOWERS AND STORMS ARE LIKELY THROUGHOUT
THE DAY. LOCALLY HEAVY RAIN AND MINOR STREET FLOODING IS POSSIBLE.
CLOUD COVER AND RAINFALL IS FORECAST TO KEEP TEMPS IN THE 80S. THE
AREA OF LOW PRESSURE IS FORECAST TO MOVE SOUTHWEST INTO THE GULF
OF MEXICO FRIDAY NIGHT...AND RAIN CHANCES WILL CONTINUE ACROSS
COASTAL AREAS.
SATURDAY AND SUNDAY...DEEP MOISTURE WILL REMAIN ACROSS SOUTH
FLORIDA THROUGH THE WEEKEND. THE ECMWF KEEPS A TROUGH AXIS
LINGERING OVER THE REGION EXTENDING TO THE EAST OF THE AREA OF LOW
PRESSURE THROUGH SUNDAY. THE GFS MOVES THE SYSTEM QUICKLY
WESTWARD ACROSS THE GULF...WITH A RETURN OF THE DEEP EAST TO
SOUTHEAST FLOW OBSERVED OVER THE PAST SEVERAL DAYS ON SUNDAY AS
THE RIDGE BUILDS WESTWARD ACROSS THE REGION. SO RAIN CHANCES WILL
REMAIN IN THE LIKELY CATEGORY ON SATURDAY...AND THEN COME DOWN A
LITTLE ON SUNDAY.
HIGH PRESSURE WILL THEN BUILD ACROSS THE REGION EARLY NEXT
WEEK...WITH A MORE TYPICAL EASTERLY FLOW RAINY SEASON PATTERN.
&&
.AVIATION...
INCREASING RAINFALL CHANCES WILL REMAIN POSSIBLE AS A WEAK AREA OF
LOW PRESSURE TRACKS WESTWARD INTO THE LOCAL AREA TODAY THROUGH
FRIDAY. WINDS WILL REMAIN LIGHT AND MAINLY DRIVEN BY THE LAND/SEA
BREEZES AND AFTERNOON CONVECTION. WILL INCLUDE VCTS AT ALL SITES
AFTER 15Z AND UPDATE AS CONDITIONS EVOLVE. /85
&&
.MARINE...
A WEAK AREA OF LOW PRESSURE NEAR THE NORTHERN BAHAMAS IS FORECAST
TO PUSH SLOWLY WEST ACROSS THE LOCAL ATLANTIC WATERS TONIGHT AND
THEN INTO THE GULF WATERS FRIDAY NIGHT. THE NHC IS MONITORING
THIS DISTURBANCE...AND THIS COULD IMPACT THE FORECAST FOR FRIDAY
AND INTO THE WEEKEND. LIGHT WINDS ARE FORECAST TODAY...WITH
GENERALLY EAST TO SOUTHEAST WINDS FRIDAY THROUGH THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 88 75 86 76 / 60 40 60 20
FORT LAUDERDALE 89 76 88 77 / 60 40 60 30
MIAMI 88 75 86 77 / 60 30 70 30
NAPLES 90 74 89 75 / 50 30 60 30
&&
.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 DODGE CITY KS
322 AM CDT THU SEP 11 2014
...UPDATED FOR THE LONG TERM...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 112 AM CDT THU SEP 11 2014
SHORT TERM MODELS INDICATE AN UPPER LEVEL SHORTWAVE TROUGH DIGGING
SOUTHEAST ACROSS THE NORTHERN ROCKIES TODAY AND PUSHING FURTHER
SOUTHEAST INTO THE WESTERN HIGH PLAINS TONIGHT SETTING UP PRECIP
CHANCES ACROSS NEBRASKA SOUTHWARD INTO PORTIONS OF WESTERN KANSAS.
AS THE SHORTWAVE APPROACHES THIS EVENING, A SERIES OF H5 VORT MAXIMA
WILL BEGIN TO EJECT EASTWARD OUT OF THE COLORADO ROCKIES INTO THE
HIGH PLAINS OF EASTERN COLORADO AND WESTERN KANSAS. MEANWHILE, AN
ATTENDANT COLD FRONT TO THE SHORTWAVE WILL BEGIN TO PUSH SOUTHWARD
ACROSS WESTERN KANSAS LATE THIS EVENING INTO EARLY FRIDAY MORNING.
OVERNIGHT, DYNAMIC SUPPORT ALOFT WILL BECOME MORE FAVORABLE AS THE
RIGHT FRONT ENTRANCE REGION TO A +90KT JET EXITING THE APPROACHING
TROUGH AXIS SHIFTS SOUTHWARD INTO WESTERN KANSAS. AS A RESULT, RAIN
CHANCES WILL INCREASE ACROSS WESTERN KANSAS THIS EVENING, SPREADING
SOUTH AND EAST ACROSS THE REGION OVERNIGHT. A FEW ISOLATED
THUNDERSTORMS WILL BE POSSIBLE ACROSS EXTREME SOUTHWEST KANSAS THIS
EVENING WHERE SOME INCREASED INSTABILITY AND MORE FAVORABLE VERTICAL
SHEAR PROFILES WILL EXIST IN A SOUTHEASTERLY UPSLOPE FLOW. HOWEVER,
NAM/GFS MODEL SOUNDINGS INDICATE LIMITED INSTABILITY WITH CAPE
VALUES REMAINING WELL UNDER 1000 J/KG. THIS WILL RESTRICT THE
POTENTIAL FOR SEVERE STORMS ACROSS SOUTHWEST KANSAS.
TEMPERATURES WILL BE WELL BELOW NORMAL TODAY AS COOLER AIR FILTERS
SOUTHWARD INTO WESTERN KANSAS AHEAD OF A BROAD SURFACE HIGH MOVING
SOUTHEASTWARD OUT OF THE NORTHERN ROCKIES INTO THE HIGH PLAINS OF
EASTERN WYOMING AND WESTERN NEBRASKA. THE NAM AND GFS SHOW H85
TEMPERATURES FALLING BELOW 10C ACROSS CENTRAL KANSAS NEAR THE I-70
CORRIDOR BY THIS AFTERNOON WITH THE MID TO UPPER TEENS(C) ACROSS
EXTREME SOUTHWEST KANSAS WITHIN A SOUTHEAST UPSLOPE FLOW.
ADDITIONALLY, HIGH TEMPERATURES MAY BE HINDERED TODAY DEPENDING ON
HOW FAR SOUTH LOW LEVEL STRATUS MOVING OUT OF NEBRASKA THIS
MORNING PUSHES INTO SOUTHWEST KANSAS, NOT TO MENTION HOW LONG IT
MAY LAST. THE HRRR SUGGESTS THE STRATUS DECK PERSISTING THROUGH AT
LEAST MID DAY, PARTICULARLY ACROSS CENTRAL KANSAS IN THE VICINITY
OF THE I-70 CORRIDOR. BECAUSE OF THIS, HIGHS MAY STRUGGLE TO REACH
THE 60S(F) IN CENTRAL KANSAS WITH THE LOWER TO MID 70S(F) POSSIBLE
CLOSER TO THE OKLAHOMA BORDER, ESPECIALLY IN EXTREME SOUTHWEST
KANSAS. A SECONDARY PUSH OF COLDER AIR BEHIND YET ANOTHER COLD
FRONT PUSHING ACROSS WESTERN KANSAS EARLY FRIDAY MORNING WILL
LIKELY DROP LOWS DOWN INTO THE 40S(F) ACROSS MUCH OF CENTRAL AND
SOUTHWEST KANSAS TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 318 AM CDT THU SEP 11 2014
FRIDAY WILL BE COOL AND MOIST, WITH LIGHT RAIN LIKELY.
FRIDAY WILL BE IN A POST FRONTAL REGIME, WITH COOL HIGH PRESSURE
BUILDING IN FROM THE NORTHWEST. THE SURFACE FLOW WILL BE UPSLOPE
WITH NORTHEAST TO EASTERLY WINDS AT 10 TO 20 MPH. CLOUDS WILL BE
THICKEST IN THE MORNING, BUT STILL PREVALENT IN THE AFTERNOON. MAX
TEMPS WILL GENERALLY BE IN THE 50S, BUT I ONLY EXPECT LIGHT RAIN
WITH 0.05 TO 0.10 INCH ACCUMULATION. THE HIGH PRESSURE WILL BEGIN
TO DOMINATE FRIDAY EVENING, LEADING TO CLEAR SKIES OVERNIGHT. THE
COOL AIR WILL FILTRATE IN FROM THE NORTHWEST, AND FROST MAY BE
POSSIBLE IN OUR EXTREME NORTHWESTERN COUNTIES OF TREGO, AND
NORTHERN LANE AND SCOTT COUNTIES SATURDAY MORNING. AS THAT TIME
FRAME APPROACHES, WE WILL NEED TO LOOK INTO A POSSIBLE WATCH OR
REFINE THE AREA WHERE FROST MAY OCCUR.
AFTER THE FALL-LIKE WEATHER ON FRIDAY, SATURDAY AND SUNDAY WILL
SHOW A GRADUAL WARM UP, WITH HIGHS REACHING THE MID 60S TO LOWER
70S ON SATURDAY, AND BOUNDING UPWARD TO THE UPPER 70S TO LOWER 80S
BY SUNDAY. A COLD FRONT WILL PLOW THROUGH TO THE SOUTHEAST ON
MONDAY AFTERNOON, BRINGING A CHANCE FOR THUNDERSTORMS TO OUR
SOUTHEAST-MOST ZONES, PRIMARILY IN PRATT AND BARBER COUNTIES. AN
UPPER LEVEL WAVE WILL COME THROUGH IN THE FLOW MONDAY NIGHT,
GIVING MOST OF THE CWA A 20 TO 30 PERCENT CHANCE FOR
THUNDERSTORMS. A LEE SIDE TROUGH WILL BE IN WESTERN KANSAS TUESDAY
AND WEDNESDAY, AND SLIGHT CHANCES FOR SHOWERS AND ISOLATED
THUNDERSTORMS WILL EXIST ACROSS MOST OF OUR FORECAST AREA, MAINLY
THE EAST.
WEDNESDAY WILL SEE A RETURN TO A WARM SOUTHWEST FLOW, AND HIGH
TEMPERATURES WILL RESPOND LIKEWISE WITH VALUES IN THE LOWER 80S
NORTH OF I-70 AND THE MIDDLE 80S SOUTHWEST A LINE FROM GARDEN CITY
TO DODGE CITY TO MEDICINE LODGE. WINDS THROUGH THE EXTENDED DO NOT
LOOK TOO STRONG, EXCEPT AHEAD OF THE FRONT ON MONDAY, AND THEN
AGAIN BEHIND THE FRONT ON TUESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1200 AM CDT THU SEP 11 2014
LOW LEVEL STRATUS ACROSS MUCH OF NEBRASKA IS EXPECTED TO SHIFT SOUTH-
SOUTHWEST INTO CENTRAL AND PORTIONS OF SOUTHWEST KANSAS EARLY
THIS MORNING DROPPING CIGS WELL DOWN INTO THE MVFR CATEGORY IN
THE VICINITY OF ALL TAF SITES. AS RELATIVE HUMIDITY INCREASES,
BRIEF PERIODS OF IFR CIGS MAY BE POSSIBLE TOWARD SUNRISE WITH CIGS
BEGINNING TO SLOWLY LIFT THROUGH THURSDAY AFTERNOON. LIGHT
NORTHEASTERLY WINDS WILL PERSIST ACROSS CENTRAL AND SOUTHWEST
KANSAS EARLY THIS MORNING AS SURFACE HIGH PRESSURE BEGINS TO
SHIFT SOUTHEAST ACROSS THE NORTHERN PLAINS. WINDS MAY BECOME MORE
EASTERLY DURING THE DAY THURSDAY AS THE SURFACE HIGH PUSHES
FURTHER SOUTHEAST INTO NEBRASKA.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 65 45 53 40 / 10 70 70 0
GCK 65 42 50 38 / 10 70 70 0
EHA 75 45 51 43 / 20 80 70 0
LBL 72 48 54 42 / 10 70 70 0
HYS 58 42 52 38 / 10 70 70 0
P28 65 50 58 43 / 10 70 70 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JJOHNSON
LONG TERM...BURKE
AVIATION...JJOHNSON
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
115 AM CDT THU SEP 11 2014
...UPDATE TO SHORT TERM...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 112 AM CDT THU SEP 11 2014
SHORT TERM MODELS INDICATE AN UPPER LEVEL SHORTWAVE TROUGH DIGGING
SOUTHEAST ACROSS THE NORTHERN ROCKIES TODAY AND PUSHING FURTHER
SOUTHEAST INTO THE WESTERN HIGH PLAINS TONIGHT SETTING UP PRECIP
CHANCES ACROSS NEBRASKA SOUTHWARD INTO PORTIONS OF WESTERN KANSAS.
AS THE SHORTWAVE APPROACHES THIS EVENING, A SERIES OF H5 VORT MAXIMA
WILL BEGIN TO EJECT EASTWARD OUT OF THE COLORADO ROCKIES INTO THE
HIGH PLAINS OF EASTERN COLORADO AND WESTERN KANSAS. MEANWHILE, AN
ATTENDANT COLD FRONT TO THE SHORTWAVE WILL BEGIN TO PUSH SOUTHWARD
ACROSS WESTERN KANSAS LATE THIS EVENING INTO EARLY FRIDAY MORNING.
OVERNIGHT, DYNAMIC SUPPORT ALOFT WILL BECOME MORE FAVORABLE AS THE
RIGHT FRONT ENTRANCE REGION TO A +90KT JET EXITING THE APPROACHING
TROUGH AXIS SHIFTS SOUTHWARD INTO WESTERN KANSAS. AS A RESULT, RAIN
CHANCES WILL INCREASE ACROSS WESTERN KANSAS THIS EVENING, SPREADING
SOUTH AND EAST ACROSS THE REGION OVERNIGHT. A FEW ISOLATED
THUNDERSTORMS WILL BE POSSIBLE ACROSS EXTREME SOUTHWEST KANSAS THIS
EVENING WHERE SOME INCREASED INSTABILITY AND MORE FAVORABLE VERTICAL
SHEAR PROFILES WILL EXIST IN A SOUTHEASTERLY UPSLOPE FLOW. HOWEVER,
NAM/GFS MODEL SOUNDINGS INDICATE LIMITED INSTABILITY WITH CAPE
VALUES REMAINING WELL UNDER 1000 J/KG. THIS WILL RESTRICT THE
POTENTIAL FOR SEVERE STORMS ACROSS SOUTHWEST KANSAS.
TEMPERATURES WILL BE WELL BELOW NORMAL TODAY AS COOLER AIR FILTERS
SOUTHWARD INTO WESTERN KANSAS AHEAD OF A BROAD SURFACE HIGH MOVING
SOUTHEASTWARD OUT OF THE NORTHERN ROCKIES INTO THE HIGH PLAINS OF
EASTERN WYOMING AND WESTERN NEBRASKA. THE NAM AND GFS SHOW H85
TEMPERATURES FALLING BELOW 10C ACROSS CENTRAL KANSAS NEAR THE I-70
CORRIDOR BY THIS AFTERNOON WITH THE MID TO UPPER TEENS(C) ACROSS
EXTREME SOUTHWEST KANSAS WITHIN A SOUTHEAST UPSLOPE FLOW.
ADDITIONALLY, HIGH TEMPERATURES MAY BE HINDERED TODAY DEPENDING ON
HOW FAR SOUTH LOW LEVEL STRATUS MOVING OUT OF NEBRASKA THIS
MORNING PUSHES INTO SOUTHWEST KANSAS, NOT TO MENTION HOW LONG IT
MAY LAST. THE HRRR SUGGESTS THE STRATUS DECK PERSISTING THROUGH AT
LEAST MID DAY, PARTICULARLY ACROSS CENTRAL KANSAS IN THE VICINITY
OF THE I-70 CORRIDOR. BECAUSE OF THIS, HIGHS MAY STRUGGLE TO REACH
THE 60S(F) IN CENTRAL KANSAS WITH THE LOWER TO MID 70S(F) POSSIBLE
CLOSER TO THE OKLAHOMA BORDER, ESPECIALLY IN EXTREME SOUTHWEST
KANSAS. A SECONDARY PUSH OF COLDER AIR BEHIND YET ANOTHER COLD
FRONT PUSHING ACROSS WESTERN KANSAS EARLY FRIDAY MORNING WILL
LIKELY DROP LOWS DOWN INTO THE 40S(F) ACROSS MUCH OF CENTRAL AND
SOUTHWEST KANSAS TONIGHT.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 343 PM CDT WED SEP 10 2014
PRECIPITATION EPISODE THURSDAY NIGHT INTO THE FIRST HALF OF FRIDAY
APPEARS TO BE ON TRACK. THERE REALLY WAS NOT A MAJOR CHANGE IN THE
OVERALL THINKING REGARDING TIMING OF THE FRONT, PRECIPITATION,
ETC...BUT THERE WERE A COUPLE OF ADJUSTMENTS. FIRST, IT APPEARS
THAT MUCH OF THE PRECIPITATION INITIALLY ACROSS FAR WEST-CENTRAL AND
SOUTHWEST KANSAS WILL BE CONVECTIVE IN NATURE. INTENSE CYCLOGENESIS
DURING THE LATE DAY WILL ALLOW SURFACE MOISTURE TO DRAW NORTHWEST
INTO FAR SOUTHEASTERN COLORADO/ADJACENT FAR SOUTHWEST KANSAS. THE
NAM12 SHOWS A MESOSCALE AREA OF SURFACE-BASED CAPE AROUND 1000 J/KG,
HOWEVER ANY SURFACE BASED STORMS SHOULD QUICKLY BECOME ELEVATED
ABOVE A SURGING COLD AIRMASS FROM THE NORTH. EVENTUALLY, THE NATURE
OF PRECIPITATION (ESPECIALLY BY 06Z) WILL BECOME STRATIFORM, SO IN
THE GRIDS WE WILL CONTINUE TO CARRY "RAIN" AS THE PRECIPITATION
(INSTEAD OF SHOWERS/THUNDERSTORMS). AS FAR AS FRIDAY GOES, THE FIRST
HALF OF THE DAY WILL BE COMPOSED OF NORTH WINDS, LOW STRATUS, RAIN,
AND TEMPERATURES IN THE 40S FOR MUCH OF THE SOUTHWEST KANSAS REGION,
WHICH IS A STARK CHANGE TO SOME OF THE SUMMER WARMTH WE HAVE BEEN
SEEING. FRIDAY HIGHS WILL OCCUR AT MIDNIGHT WITH TEMPERATURES FROM
THE MID-UPPER 50S TO LOWER 60S. BY MID-MORNING, MOST EVERYONE WILL
BE IN THE MID TO UPPER 40S...WITH STEADY TEMPERATURES THROUGH EARLY
AFTERNOON. EVENTUALLY, CLOUDS WILL BREAK UP WITH SOME DIRECT
INSOLATION BEING REALIZED, HELPING OFFSET THE COLD ADVECTION AS
TEMPERATURES WARM INTO THE 50 TO 53F RANGE. SATURDAY MORNING WILL BE
RATHER CHILLY WITH NEAR-RECORD LOW TEMPERATURES FOR MOST LOCATIONS.
WE WILL BE GOING FOR LOWS OF 36F DOWN TO A SCOTT CITY TO WAKEENEY
LINE WITH UPPER 30S AS FAR SOUTH AS THE ARKANSAS RIVER. THE ECMWF IS
THE MOST AGGRESSIVE MODEL SHOWING THE CENTER OF A NEAR 1030MB HIGH
FROM SOUTHWEST KANSAS INTO SOUTHWEST IOWA AND NEARLY CALM WINDS. IT
LOOKS LIKE AN IDEAL RADIATIONAL COOLING NIGHT, PER THE ECMWF, AND IT
IS CERTAINLY CONCEIVABLE WE SEE MORE AREAS OF THE WEST-
CENTRAL/SOUTHWEST KANSAS REGION 36F OR EVEN COOLER YIELDING SOME
FROST.
WE WILL BEGIN TO WARM BACK UP OVER THE WEEKEND AS THE HIGH DEPARTS
AND THE LOW LEVEL AIRMASS MODIFIES. THE FORECAST IS DRY THROUGH LATE
SUNDAY, HOWEVER SUNDAY EVENING/NIGHT SOME WARM ADVECTION IN THE 800-
900MB LAYER MAY SUPPORT SOME NOCTURNAL SHOWERS/THUNDERSTORMS AND WE
WILL HAVE SOME 20 POPS IN CENTRAL/SOUTH CENTRAL KANSAS FOR THAT
POSSIBILITY. ANOTHER FRONTAL PASSAGE IS ANTICIPATED MONDAY WITH
COOLER AIR SETTLING BACK IN AS ANOTHER DECENT SHORTWAVE TROUGH MOVES
EAST-SOUTHEAST ACROSS THE NORTHERN PLAINS INTO THE UPPER MIDWEST
REGION. HIGHEST POPS (30 PERCENT) WILL BE MONDAY NIGHT WITHIN THE
BAROCLINIC ZONE 800-700MB. IT IS STILL PRETTY FAR AWAY IN THE
FORECAST, BUT TUESDAY HIGHS WILL LIKELY BE LOWERED IF SUCCESSIVE
GLOBAL SPECTRAL MODEL RUNS CONTINUE TO SHOW A FAIRLY DECENT FRONTAL
PASSAGE AS THE 12Z RUNS SHOWED TODAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1200 AM CDT THU SEP 11 2014
LOW LEVEL STRATUS ACROSS MUCH OF NEBRASKA IS EXPECTED TO SHIFT SOUTH-
SOUTHWEST INTO CENTRAL AND PORTIONS OF SOUTHWEST KANSAS EARLY
THIS MORNING DROPPING CIGS WELL DOWN INTO THE MVFR CATEGORY IN
THE VICINITY OF ALL TAF SITES. AS RELATIVE HUMIDITY INCREASES,
BRIEF PERIODS OF IFR CIGS MAY BE POSSIBLE TOWARD SUNRISE WITH CIGS
BEGINNING TO SLOWLY LIFT THROUGH THURSDAY AFTERNOON. LIGHT
NORTHEASTERLY WINDS WILL PERSIST ACROSS CENTRAL AND SOUTHWEST
KANSAS EARLY THIS MORNING AS SURFACE HIGH PRESSURE BEGINS TO
SHIFT SOUTHEAST ACROSS THE NORTHERN PLAINS. WINDS MAY BECOME MORE
EASTERLY DURING THE DAY THURSDAY AS THE SURFACE HIGH PUSHES
FURTHER SOUTHEAST INTO NEBRASKA.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 67 45 53 40 / 10 70 70 0
GCK 67 42 50 38 / 10 70 70 0
EHA 75 45 51 43 / 20 80 70 0
LBL 72 48 54 42 / 10 70 70 0
HYS 60 42 52 38 / 10 70 70 0
P28 72 50 58 43 / 10 70 70 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JJOHNSON
LONG TERM...UMSCHEID
AVIATION...JJOHNSON
AREA FORECAST DISCUSSION
NWS JACKSON KY
431 AM EDT THU SEP 11 2014
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 323 AM EDT THU SEP 11 2014
THE MODELS WERE IN GOOD AGREEMENT WITH THE LARGE SCALE AND LOCAL
WEATHER PATTERN FOR THE FIRST 36 HOURS OF THE FORECAST. THE
NAM12...SREF...AND HRRR MODELS HAVE ALL HANDLED THE TIMING AND
EVOLUTION OF A LINE OF SHOWERS AND STORMS THAT IS CURRENTLY MOVING
ACROSS CENTRAL KENTUCKY AND SOUTHERN OHIO. THE NAM12 AND SREF SEEM TO
DO A BETTER JOB OF HANDLING THE EVOLUTION OF THIS LINE OF SHOWERS AND
STORMS AFTER SUNRISE TODAY THAN THE HRRR...SO THOSE TWO MODELS WERE
USED TO CREATE THE NEW FORECAST. THE MODELS SUGGEST A STRONG COLD
FRONT WILL MOVE ACROSS CENTRAL AND EASTERN KENTUCKY TODAY...WITH THE
BOUNDARY EXITING THE AREA LATE THIS AFTERNOON. WIDESPREAD SHOWERS AND
STORMS ARE EXPECTED TO CONTINUE FIRING ALONG AND JUST AHEAD OF THIS
FRONT...WITH THE PEAK IN ACTIVITY OCCURRING BETWEEN ROUGHLY NOON AND
5 PM. THE LATEST FORECAST SOUNDINGS CONTINUE TO SUPPORT THE POTENTIAL
FOR LOCALLY HEAVY RAINFALL...WITH PRECIPITABLE WATER VALUES OF AROUND
2 INCHES PERSISTING THROUGH THE OVERNIGHT HOURS. SOME OF THE STRONGER
THUNDERSTORMS COULD ALSO PRODUCE GUSTY WINDS...BUT LOCALLY HEAVY
RAINFALL WILL BE THE PRIMARY THREAT. THE RAIN CHANCES WILL NOT END
ONCE THE FRONT HAS PASSED BY US...HOWEVER. THE BOUNDARY IS EXPECTED
TO STALL ACROSS THE TENNESSEE VALLEY ON FRIDAY. WAVES OF LOW PRESSURE
ARE THEN PROGGED TO MIGRATE FROM WEST TO EAST ALONG THE FRONT. THESE
DISTURBANCES WILL BRING ENOUGH LIFT AND MOISTURE TO LOCATIONS SOUTH
OF THE MOUNTAIN PARKWAY TO PERHAPS FIRE OFF ISOLATED TO SCATTERED
RAIN SHOWERS LATE TONIGHT THROUGH THE END OF THE DAY ON FRIDAY.
ONCE THE FRONT MOVES THROUGH EARLY TONIGHT...AN UNSEASONABLY COOL
CANADIAN AIR MASS WILL SETTLE OVER THE AREA. THIS AIR MASS WILL BRING
FALL LIKE TEMPERATURES TO EASTERN KENTUCKY TONIGHT AND FRIDAY. THE
COOL WEATHER WILL FIRST BE EXPERIENCED LATE TONIGHT...AS WINDS SHIFT
TO THE NORTH AND THE COOL AIR FULLY INVADES THE REGION. TONIGHTS
LOWS ARE EXPECTED TO BOTTOM OUT IN THE LOW TO MID 60S FOR MOST
LOCATIONS. FOLKS ALONG AND NORTH OF THE I-64 CORRIDOR MAY SEE THE
MERCURY DIP INTO THE UPPER 50S BY FRIDAY MORNING. HIGH TEMPERATURES
ON FRIDAY WILL LIKELY ONLY CLIMB INTO THE LOW TO MID 70S ACROSS THE
AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 431 AM EDT THU SEP 11 2014
THE MODELS ARE IN GOOD AGREEMENT WITH THE LONG WAVE PATTERN THROUGH
THE PERIOD. PROGRESSIVE AND AMPLIFIED FLOW WILL CONTROL ACROSS THE
NORTHERN HALF OF THE CONUS AS SEVERAL PASSING SHORT WAVES HELP TO
REINFORCE TROUGHING ACROSS THE REGION. UPPER LEVEL RIDGING HANGING ON
ACROSS THE SOUTHERN CONUS WILL GRADUALLY DAMPEN AND GET SUPPRESSED
FURTHER SOUTH INTO EARLY NEXT WEEK...BEFORE CONSOLIDATING MORE ACROSS
THE DESERT SOUTHWEST BY THE MIDDLE OF NEXT WEEK.
FOR EASTERN KENTUCKY...THE FIRST MAIN SHORT WAVE WILL MOVE THROUGH
FRIDAY NIGHT INTO SATURDAY...BRINGING A CHANCE OF SHOWERS. GENERALLY
DRY WEATHER CAN BE EXPECTED FROM SATURDAY NIGHT THROUGH SUNDAY
NIGHT...AS HIGH PRESSURE TEMPORARILY BUILDS IN AT THE SURFACE. A
DEEPER TROUGH AXIS...WITH SOME SURFACE DEVELOPMENT NOTED BY THE
MODELS...WILL THEN AFFECT THE AREA FROM MONDAY THROUGH
TUESDAY. THIS SYSTEM WILL BRING SOME RENEWED CHANCES OF
SHOWERS...ALTHOUGH THERE WILL NOT BE AS MUCH LOW LEVEL MOISTURE TO
WORK WITH...SO STUCK FAIRLY CLOSE TO THE BLENDED GUIDANCE ON THE
POPS. DRY WEATHER WILL ENSUE ONCE AGAIN THEREAFTER...AS SURFACE HIGH
PRESSURE BUILDS IN ACROSS THE OHIO VALLEY.
TEMPERATURES WILL AVERAGE BELOW NORMAL THROUGH THE PERIOD...WITH
HIGHS MAINLY IN THE LOW TO MID 70S AND LOWS IN THE 50S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 140 AM EDT THU SEP 11 2014
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH AROUND 11Z THIS
MORNING AT THE PRIMARY TAF SITES. IT LOOKS LIKE THE FIRST SHOWERS AND
STORMS WILL BEGIN MOVING ACROSS THE TAF SITES BEGINNING AT 10Z FOR
SME...11Z FOR LOZ...12Z FOR JKL...AND 13Z FOR SJS. MVFR TO IFR
CONDITIONS WILL BE POSSIBLE WITH ANY THUNDERSTORMS OR INTENSE
SHOWERS. LOCALLY HEAVY RAINFALL AND LIGHTNING WILL THE PRIMARY
CONCERNS FOR AVIATORS WITH ANY SHOWERS OR STORMS. THE COLD FRONT THAT
IS PRODUCING THE PRECIPITATION SHOULD BE THROUGH THE AREA BY AROUND
0Z THIS EVENING...WITH WINDS SHIFTING FROM SOUTHWEST TO WEST BEHIND
THE FRONT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...AR
LONG TERM...GEOGERIAN
AVIATION...AR
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
323 AM EDT THU SEP 11 2014
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 3 23AM EDT THU SEP 11 2014
THE MODELS WERE IN GOOD AGREEMENT WITH THE LARGE SCALE AND LOCAL
WEATHER PATTERN FOR THE FIRST 36 HOURS OF THE FORECAST. THE
NAM12...SREF...AND HRRR MODELS HAVE ALL HANDLED THE TIMING AND
EVOLUTION OF A LINE OF SHOWERS AND STORMS THAT IS CURRENTLY MOVING
ACROSS CENTRAL KENTUCKY AND SOUTHERN OHIO. THE NAM12 AND SREF SEEM TO
DO A BETTER JOB OF HANDLING THE EVOLUTION OF THIS LINE OF SHOWERS AND
STORMS AFTER SUNRISE TODAY THAN THE HRRR...SO THOSE TWO MODELS WERE
USED TO CREATE THE NEW FORECAST. THE MODELS SUGGEST A STRONG COLD
FRONT WILL MOVE ACROSS CENTRAL AND EASTERN KENTUCKY TODAY...WITH THE
BOUNDARY EXITING THE AREA LATE THIS AFTERNOON. WIDESPREAD SHOWERS AND
STORMS ARE EXPECTED TO CONTINUE FIRING ALONG AND JUST AHEAD OF THIS
FRONT...WITH THE PEAK IN ACTIVITY OCCURRING BETWEEN ROUGHLY NOON AND
5 PM. THE LATEST FORECAST SOUNDINGS CONTINUE TO SUPPORT THE POTENTIAL
FOR LOCALLY HEAVY RAINFALL...WITH PRECIPITABLE WATER VALUES OF AROUND
2 INCHES PERSISTING THROUGH THE OVERNIGHT HOURS. SOME OF THE STRONGER
THUNDERSTORMS COULD ALSO PRODUCE GUSTY WINDS...BUT LOCALLY HEAVY
RAINFALL WILL BE THE PRIMARY THREAT. THE RAIN CHANCES WILL NOT END
ONCE THE FRONT HAS PASSED BY US...HOWEVER. THE BOUNDARY IS EXPECTED
TO STALL ACROSS THE TENNESSEE VALLEY ON FRIDAY. WAVES OF LOW PRESSURE
ARE THEN PROGGED TO MIGRATE FROM WEST TO EAST ALONG THE FRONT. THESE
DISTURBANCES WILL BRING ENOUGH LIFT AND MOISTURE TO LOCATIONS SOUTH
OF THE MOUNTAIN PARKWAY TO PERHAPS FIRE OFF ISOLATED TO SCATTERED
RAIN SHOWERS LATE TONIGHT THROUGH THE END OF THE DAY ON FRIDAY.
ONCE THE FRONT MOVES THROUGH EARLY TONIGHT...AN UNSEASONABLY COOL
CANADIAN AIR MASS WILL SETTLE OVER THE AREA. THIS AIR MASS WILL BRING
FALL LIKE TEMPERATURES TO EASTERN KENTUCKY TONIGHT AND FRIDAY. THE
COOL WEATHER WILL FIRST BE EXPERIENCED LATE TONIGHT...AS WINDS SHIFT
TO THE NORTH AND THE COOL AIR FULLY INVADES THE REGION. TONIGHTS
LOWS ARE EXPECTED TO BOTTOM OUT IN THE LOW TO MID 60S FOR MOST
LOCATIONS. FOLKS ALONG AND NORTH OF THE I-64 CORRIDOR MAY SEE THE
MERCURY DIP INTO THE UPPER 50S BY FRIDAY MORNING. HIGH TEMPERATURES
ON FRIDAY WILL LIKELY ONLY CLIMB INTO THE LOW TO MID 70S ACROSS THE
AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 323 AM EDT THU SEP 11 2014
AN EXTENDED DISCUSSION WILL BE ISSUED SHORTLY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 140 AM EDT THU SEP 11 2014
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH AROUND 11Z THIS
MORNING AT THE PRIMARY TAF SITES. IT LOOKS LIKE THE FIRST SHOWERS AND
STORMS WILL BEGIN MOVING ACROSS THE TAF SITES BEGINNING AT 10Z FOR
SME...11Z FOR LOZ...12Z FOR JKL...AND 13Z FOR SJS. MVFR TO IFR
CONDITIONS WILL BE POSSIBLE WITH ANY THUNDERSTORMS OR INTENSE
SHOWERS. LOCALLY HEAVY RAINFALL AND LIGHTNING WILL THE PRIMARY
CONCERNS FOR AVIATORS WITH ANY SHOWERS OR STORMS. THE COLD FRONT THAT
IS PRODUCING THE PRECIPITATION SHOULD BE THROUGH THE AREA BY AROUND
0Z THIS EVENING...WITH WINDS SHIFTING FROM SOUTHWEST TO WEST BEHIND
THE FRONT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...AR
LONG TERM...GEOGERIAN
AVIATION...AR
AREA FORECAST DISCUSSION
NWS JACKSON KY
306 AM EDT THU SEP 11 2014
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 305 AM EDT THU SEP 11 2014
THE MODELS WERE IN GOOD AGREEMENT WITH THE LARGE SCALE AND LOCAL
WEATHER PATTERN FOR THE FIRST 36 HOURS OF THE FORECAST. THE
NAM12...SREF...AND HRRR MODELS HAVE ALL HANDLED THE TIMING AND
EVOLUTION OF A LINE OF SHOWERS AND STORMS THAT IS CURRENTLY MOVING
ACROSS CENTRAL KENTUCKY AND SOUTHERN OHIO. THE NAM12 AND SREF SEEM TO
DO A BETTER JOB OF HANDLING THE EVOLUTION OF THIS LINE OF SHOWERS AND
STORMS AFTER SUNRISE TODAY THAN THE HRRR...SO THOSE TWO MODELS WERE
USED TO CREATE THE NEW FORECAST. THE MODELS SUGGEST A STRONG COLD
FRONT WILL MOVE ACROSS CENTRAL AND EASTERN KENTUCKY TODAY...WITH THE
BOUNDARY EXITING THE AREA LATE THIS AFTERNOON. WIDESPREAD SHOWERS AND
STORMS ARE EXPECTED TO CONTINUE FIRING ALONG AND JUST AHEAD OF THIS
FRONT...WITH THE PEAK IN ACTIVITY OCCURRING BETWEEN ROUGHLY NOON AND
5 PM. THE LATEST FORECAST SOUNDINGS CONTINUE TO SUPPORT THE POTENTIAL
FOR LOCALLY HEAVY RAINFALL...WITH PRECIPITABLE WATER VALUES OF AROUND
2 INCHES PERSISTING THROUGH THE OVERNIGHT HOURS. SOME OF THE STRONGER
THUNDERSTORMS COULD ALSO PRODUCE GUSTY WINDS...BUT LOCALLY HEAVY
RAINFALL WILL BE THE PRIMARY THREAT. ONCE THE FRONT MOVES THROUGH
EARLY TONIGHT...AN UNSEASONABLY COOL CANADIAN AIR MASS WILL SETTLE
OVER THE AREA. THIS AIR MASS WILL BRING FALL LIKE TEMPERATURES TO
EASTERN KENTUCKY TONIGHT AND FRIDAY. THE COOL WEATHER WILL FIRST BE
EXPERIENCED LATE TONIGHT...AS WINDS SHIFT TO THE NORTH AND THE COOL
AIR FULL INVADES THE REGIONS. TONIGHTS LOWS ARE EXPECTED TO BOTTOM
OUT IN THE LOW TO MID 60S FOR MOST LOCATIONS. FOLKS ALONG AND NORTH
OF THE I-64 CORRIDOR MAY SEE THE MERCURY DIP INTO THE UPPER 50S BY
FRIDAY MORNING. HIGH TEMPERATURES ON FRIDAY WILL LIKELY ONLY CLIMB
INTO THE LOW TO MID 70S ACROSS THE AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 305 AM EDT THU SEP 11 2014
AN EXTENDED DISCUSSION WILL BE ISSUED SHORTLY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 140 AM EDT THU SEP 11 2014
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH AROUND 11Z THIS
MORNING AT THE PRIMARY TAF SITES. IT LOOKS LIKE THE FIRST SHOWERS AND
STORMS WILL BEGIN MOVING ACROSS THE TAF SITES BEGINNING AT 10Z FOR
SME...11Z FOR LOZ...12Z FOR JKL...AND 13Z FOR SJS. MVFR TO IFR
CONDITIONS WILL BE POSSIBLE WITH ANY THUNDERSTORMS OR INTENSE
SHOWERS. LOCALLY HEAVY RAINFALL AND LIGHTNING WILL THE PRIMARY
CONCERNS FOR AVIATORS WITH ANY SHOWERS OR STORMS. THE COLD FRONT THAT
IS PRODUCING THE PRECIPITATION SHOULD BE THROUGH THE AREA BY AROUND
0Z THIS EVENING...WITH WINDS SHIFTING FROM SOUTHWEST TO WEST BEHIND
THE FRONT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...AR
LONG TERM...GEOGERIAN
AVIATION...AR
AREA FORECAST DISCUSSION
NWS JACKSON KY
140 AM EDT THU SEP 11 2014
.UPDATE...
ISSUED AT 140 AM EDT THU SEP 11 2014
INGESTED THE LATEST OBSERVATIONAL DATA INTO THE FORECAST GRIDS TO
ESTABLISH NEW TRENDS AND FRESHEN UP THE EXISTING FORECAST FOR THE
REST OF THE NIGHT. THE CHANGES MADE TO THE GRIDS WERE MINOR ENOUGH TO
NOT WARRANT A FORECAST UPDATE AT THIS TIME.
UPDATE ISSUED AT 1049 PM EDT WED SEP 10 2014
HAVE SLOWED DOWN THE PRECIPITATION ONSET JUST A BIT MORE BASED ON THE
LATEST RADAR AND HRRR MODEL TRENDS. THE LATEST IR SATELLITE SHOWS
QUITE A BIT OF CLEARING ACROSS OUR AREA CURRENTLY...AND A FEW OF THE
NORMALLY COOLER VALLEYS HAVE ALREADY DIPPED INTO THE UPPER 60S.
CLOUDS SHOULD FILL IN NICELY BETWEEN 06 AND 12Z...HOWEVER DID LOWER
SOME OF THE LOW TEMPERATURES IN THE EAST WHERE SOME DECENT CLEARING
WILL HANG ON FOR THE NEXT 2 TO 3 HOURS...ALLOWING FOR ANOTHER DEGREE
DROP OFF OR SO. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 820 PM EDT WED SEP 10 2014
BASED ON OBS AND AFTERNOON MODEL RUNS...HAVE SLOWED THE ARRIVAL OF
PRECIP TONIGHT...BUT THE OVERNIGHT REMAINS UNCHANGED...WITH THE SAME
12 HOUR POPS FOR THE PERIOD.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 400 PM EDT WED SEP 10 2014
MODELS ARE IN GOOD AGREEMENT FOR THE WEATHER EVENT TO AFFECT US
DURING THE PERIOD. A COLD FRONT WILL MOVE SOUTHEAST...PASSING THROUGH
KY ON THURSDAY AND THURSDAY EVENING. SHOWERS WILL OCCUR NEAR AND
AHEAD OF THE FRONT...ENTERING THE JKL FORECAST AREA OVERNIGHT...WITH
MOST OF THE PRECIP EXITING INTO TN AND VA BY THURSDAY EVENING.
LIMITED HEATING IS EXPECTED ON THURSDAY AND LAPSE RATES WILL BE NEAR
MOIST ADIABATIC...AND WINDS ALOFT ONLY MODEST. SO...DESPITE AMPLE
MOISTURE...CONVECTION SHOULD NOT BE TOO RAMBUNCTIOUS. PRECIPITABLE
WATER WILL BE NEAR 2 INCHES...AND LOCALLY HEAVY RAINFALL MAY OCCUR
WHERE CELLS TRAIN...BUT THE CELLS WILL AT LEAST BE MOVING ALONG.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 400 PM EDT WED SEP 10 2014
ATTENTION TURNS TO A SIGNIFICANT SHORT WAVE THAT WILL MOVE FROM THE
NORTH PLAINS EAST TO THE GREAT LAKES FRIDAY INTO SATURDAY. THIS WAVE
MOVES PAST EAST KENTUCKY DURING THE DAY SATURDAY FOLLOWED BY
FLATTER...BUT STILL RATHER FAST...FLOW INTO THE DAY SUNDAY. FOR THIS
TIME FRAME...THROUGH THE DAY TUESDAY...WILL FAVOR A GENERAL MODEL
BLEND. THE MODELS KEEP THIS SORT OF ABNORMALLY COOL PATTERN GOING
THROUGH THEIR RUN SUGGESTING THAT OUR DAYS OF SUMMER-LIKE WEATHER MAY
BE OVER FOR THE SEASON...THOUGH BEING KENTUCKY IT WOULD NOT TAKE
MUCH OF A WIGGLE TO BRING SOME SOUTHERN WARMTH BACK NORTH. WE SHALL
SEE...
THE RUB WITH THE FORECAST THROUGH THE FIRST PART OF THE WEEKEND WILL
BE THE POSSIBILITY THAT THE FRONT DOES NOT COMPLETELY CLEAR THE CWA
AND LINGERS CLOSE ENOUGH FOR SHOWERS TO ACCOMPANY THE FALL-LIKE COOL
DOWN FOR OUR SOUTHERN MOST LOCATIONS. THE SHOWER THREAT INCREASES
DURING FRIDAY NIGHT THROUGH THE DAY SATURDAY AS A REINFORCING COLD
FRONT MOVES THROUGH THE OHIO VALLEY. THIS FRONT SHOULD HAVE A BETTER
PUSH BEHIND IT AND HELP TO CLEAR OUT LINGERING SHOWER THREATS FOR AT
LEAST A DAY OR SO ACROSS ALL OF THE AREA. THE HIGH PRESSURE
ASSOCIATED WITH THIS COOL BLAST WILL MODERATE SOMEWHAT AND MOVE BY TO
THE NORTHEAST BY MONDAY MORNING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 140 AM EDT THU SEP 11 2014
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH AROUND 11Z THIS
MORNING AT THE PRIMARY TAF SITES. IT LOOKS LIKE THE FIRST SHOWERS AND
STORMS WILL BEGIN MOVING ACROSS THE TAF SITES BEGINNING AT 10Z FOR
SME...11Z FOR LOZ...12Z FOR JKL...AND 13Z FOR SJS. MVFR TO IFR
CONDITIONS WILL BE POSSIBLE WITH ANY THUNDERSTORMS OR INTENSE
SHOWERS. LOCALLY HEAVY RAINFALL AND LIGHTNING WILL THE PRIMARY
CONCERNS FOR AVIATORS WITH ANY SHOWERS OR STORMS. THE COLD FRONT THAT
IS PRODUCING THE PRECIPITATION SHOULD BE THROUGH THE AREA BY AROUND
0Z THIS EVENING...WITH WINDS SHIFTING FROM SOUTHWEST TO WEST BEHIND
THE FRONT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AR
SHORT TERM...HAL
LONG TERM...JKL
AVIATION...AR
AREA FORECAST DISCUSSION...UPDATED
NWS PADUCAH KY
1141 PM CDT Wed Sep 10 2014
.UPDATE...
Issued at 1141 PM CDT WED SEP 10 2014
Updated the aviation discussion for the 06Z TAF issuance.
&&
.SHORT TERM...(Tonight through Friday night)
Issued at 323 PM CDT WED SEP 10 2014
The showers are still trying to dissipate over southern Illinois,
and now a tiny heavy shower has develop near KSAR in the last
scan or two. The latest HRRR indicates that there may be some
heavier convective elements with this pesky band of showers, as it
moves eastward toward the EVV Tri State late this afternoon.
Widespread cloud cover has stunted surface-based instability
today, and this may help keep the severe weather threat in check
as we move into this evening. Model soundings from southern
Illinois and southwest Indiana reveal very weak lapse rates, and
overall instability. There is decent low-level shear, possibly
enough to support a few rotating updrafts. The low-level shear
will weaken through the evening, and there is little shear above 3
km. Cannot rule out a stray severe thunderstorm, especially if it
can display supercellular characteristics. Damaging winds still
appear to be the primary concern, but large hail and a brief
tornado cannot be ruled out.
Precipitable water values are well above 2 inches, and this could
lead to some torrential rainfall. Generally followed HPC QPF
through Thursday, and this yields 1.5-2" over much of the area,
with the possible exception of the far southeast corner of the
forecast area. 1-hour and 3-hour Flash flood Guidance is well over
2", so will not be issuing a Flash Flood Watch at this time. Some
nuisance flooding in low-lying and poorly draining areas is
possible, but major problems are not expected. The heaviest rains
will be waning over the southern half of the area toward sunrise.
Still not sure when/where convective initiation will occur, but
the latest HRRR runs have been consistent and developing scattered
convection across northern portions of southeast Missouri into
southern Illinois by 00Z. Convection currently developing along
the cold front from west central Illinois into central Missouri is
moving east and should not pose any immediate concern for our
region, but figure that the convection will fill in between it and our
scattered convection through the evening.
Will keep some decent PoPs in the southeast Thursday morning, but
it should be drying out over most areas in the afternoon. Thursday
night and Friday morning should be dry, but as the next rather
sharp upper-level storm system rotates eastward out of the
central/northern Plains, would not be surprised to see some
showers develop, as moisture is drawn back northward over the
shallow Canadian airmass. This would primarily be in the south
Friday afternoon, and then throughout the area Friday night. Still
don`t think there will be much precipitation, but a slight chance
of showers seems reasonable for both periods.
As for temperatures, stayed close to the consensus of all guidance
for lows tonight with the frontal passage. With clouds,
precipitation and cool advection, went under guidance in the
southeast Thursday. Went near consensus for lows Thursday night,
and then went below guidance Friday and near or just above it Friday
night.
.LONG TERM...(Saturday through Wednesday)
Issued at 323 PM CDT WED SEP 10 2014
Surface high pressure will build into the area on Saturday,
providing much drier air and lowering temperatures. The center of
the high will pass over the Great Lakes region and then move into
the New England states. Our region should remain dry through the
weekend though as weak high pressure continues to stay situated over
us.
Models try and bring a front into the area on Monday. The front
weakens substantially as it arrives Monday into Monday night, so
chances for precipitation appear minimal at this time but cloud
cover should increase. Most of the upper level dynamics and moisture
look to be to the north of our area. However, we will have to watch
Monday night, as a few of the GFS ensemble members and the 12Z Euro
are hinting that this front could produce some light precipitation,
especially in our northwestern counties. Even the operational GFS
indicates lower level moisture increasing by Monday night.
For Tuesday, models differ on the degree of dry air filtering into
the area, in association with the area of high pressure that moves
toward us. The 12Z GFS is much more robust in scouring out the
moisture while the 00Z ECMWF seems to keep plenty of moisture
lingering until Wednesday. The 12Z run of the ECMWF is a bit more
pronounced with drying us out now but still not as much as the GFS.
Nevertheless, it looks like we`ll be dry on Tuesday. On Wednesday,
the GFS starts to bring better moisture back into the area from the
west and even hints at possible precipitation chances out in SEMO as
well. However, the 12Z run was the only run that was this quick in
bringing precipitation back in and even the 12Z ECMWF was dry.
Temperatures will be coolest on Saturday and remain in the 70s for
the majority of the extended period. There might be a few places
that reach in the lower 80s by next week. Lows will generally be in
the 50s but some upper 40s might be attainable on Saturday night
especially in the north.
&&
.AVIATION...
Issued at 1141 PM CDT WED SEP 10 2014
With the passage of a strong cold front, showers and thunderstorms
producing IFR/MVFR conditions will continue across all TAF sites
through the first third of the period. Afer the precipitation
ends. MVFR cigs will continue through 18-20Z, then VFR. Winds will
become northwest AOB 10 knots in the wake of the front through the
first half of the period, then veer around to the north.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
AVIATION/PUBLIC...JP
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
340 AM CDT Thu Sep 11 2014
.SHORT TERM: (Through Late This Afternoon)
Issued at 340 AM CDT Thu Sep 11 2014
A strong surface cold front has moved completely southeast of our
region early this morning with an extensive area of low clouds in
its wake. The radar mosaic showed the northern edge of the rain was
barely edging our region into southern Reynolds and Madison counties
in MO. The center of the airmass responsible for this cold front
was still well to the northwest of us over southern Alberta province
meaning this airmass will take considerable time to build into our
area and remain around for awhile. Temps have dipped into the 50s
for many areas north of Interstate 70, but remain in the 60s and
even lower 70s elsewhere.
A strong storm system at the upper levels will dig in across Montana
and Wyoming today and actually back the flow across our region to a
bit more southwesterly than what it is currently. This should cause
the surface front to become quasi-stationary, but still remain well
to our south. However, the better moisture in tow behind the front
will likely remain across much of southeastern MO and far southern
IL thru today. Models loosely depict a wave riding along the
stalling frontal boundary later today--more specifically late this
morning and early this afternoon--which looks to be a sufficiently
northern enough track to justify some mentionable PoP throughout a
good portion of the day in the far southern CWA in southeastern MO.
Otherwise, the atmosphere drys out enough to go with a dry forecast.
Based on PIREPs from last evening, the thickness of the cloud layer
currently over us is about 2500ft. We are less than two weeks from
the autumnal equinox and with a rather persistently decent CAA at
the low levels expected, expect this low cloud to be a bit of a
foretaste to the more stubborn cloud cover we will encounter more
frequently during the colder months. Favored a more pessimistic
cloud cover forecast a la the RAP which doesn`t really start to
break things up until later this afternoon and even then may re-gel
together tonight.
Cloudy skies for much of the day will keep temps down and this looks
like it is well handled with the 00z MOS, with maxes in the 60s.
TES
.LONG TERM: (Tonight through Wednesday)
Issued at 340 AM CDT Thu Sep 11 2014
The shortwave now diving into Montana will move into the northeast
Plains and Upper Midwest Friday. Latest guidance is in good
agreement with the speed and track of the wave as it passes north of
the area. Most of the synoptic scale lift ahead of the shortwave
will pass north of the CWFA, but we will be in the right rear
quadrant of the upper level jet and both the GFS and NAM are also
showing bands of frontogenetical forcing moving through Friday
afternoon and Friday night. Corresponding light QPF is being
produced by the models, so feel pretty confident there will be some
light rain. However am not sure how much of this precip will be
measurable so am sticking with slight chance to mid chance PoPs
Friday afternoon through Friday night as this wave moves through.
Zonal flow aloft with a 1030mb Canadian high pressure will control
the weather for the weekend. Expect this to provide the Bi-State
region with spectacular weather for those who enjoy Autumn, with
highs mainly in the mid 60s to low 70s and lows in the 40s.
Medium range guidance is indicating a pattern shift in the
atmosphere over us toward mid-week from quasi-zonal to northwest
flow aloft. The initial wave which will dig into the eastern CONUS
is forecast to pass over the Midwest Monday into Monday night. Much
like Friday`s wave, the broad synoptic lift associated with the wave
should pass north of us with a band of low level frontogenetical
forcing ahead of another cold front. Feel low chance PoPs continue
to be indicated for Monday and Monday night as this forcing affects
the region, and higher PoPs may be needed if the shortwave turns out
to be stronger than currently forecast. Another shot of Canadian
air will shift across the Midwest Tuesday into the Ohio Valley
Wednesday. Stuck close to guidance for temperatures with highs in
the 70s and lows in the 50s which continue to be below
climatology...although it may not be cool enough given the falling
heights and easterly flow as the high moves east of the area.
Carney
&&
.AVIATION: (For the 06z TAFs through 06z Thursday Night)
Issued at 1051 PM CDT Wed Sep 10 2014
Extensive area of MVFR stratus covers the Midwest in the wake of
this cold front and have a hard time seeing it dissipating
tomorrow. Northwest wind will become north-northeast by tomorrow
evening.
Specifics for KSTL:
MVFR stratus will blanket the region through tomorrow evening.
CVKING
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 66 54 66 49 / 0 5 20 30
Quincy 63 49 62 43 / 0 10 30 30
Columbia 66 52 64 45 / 0 5 30 20
Jefferson City 66 53 65 47 / 0 5 30 20
Salem 68 53 67 51 / 5 5 10 30
Farmington 67 52 66 50 / 10 10 10 30
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1251 AM CDT THU SEP 11 2014
.UPDATE...
ISSUED AT 1249 AM CDT THU SEP 11 2014
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE. THE BEST CHANCE
FOR PRECIPITATION THE REMAINDER OF THE NIGHT IS ACROSS THE FAR
SOUTHWEST IN ASSOCIATION WITH THE UPPER LEVEL LOW ACROSS CENTRAL
MONTANA THAT WILL CONTINUE TO PROPAGATE SOUTHEAST THROUGH THE
NIGHT. LIGHT SNOW MAY MIX WITH RAIN SOUTHWEST...HOWEVER NO
ACCUMULATIONS ARE EXPECTED. GIVEN CLOUD COVER...MAY CANCEL THE
FROST ADVISORY ACROSS THE TURTLE MOUNTAINS AREA THIS
MORNING...FOCUSING ANY FROST AND FREEZE HEADLINES FOR THURSDAY
NIGHT INTO FRIDAY MORNING WITH THE NEXT UPDATE.
UPDATE ISSUED AT 912 PM CDT WED SEP 10 2014
LATEST WATER VAPOR IMAGERY SHOWS A SHORTWAVE ROTATING THROUGH
SOUTHWEST NORTH DAKOTA. UPWARD VERTICAL MOTION ASSOCIATED WITH
THIS SHORTWAVE ALONG WITH THE LEFT EXIT REGION OF AN UPPER JET
ACROSS SOUTHERN NORTH DAKOTA IS PRODUCING SCATTERED RAIN
SHOWERS...WITH AN ISOLATED/BRIEF PERIOD OF SLEET WITHIN THE
STRONGEST VERTICAL MOTION FIELD. THIS WILL CONTINUE TO MOVE INTO
THE JAMES RIVER VALLEY THROUGH THIS LATE EVENING.
OTHERWISE...THE NEXT AREA OF PRECIPITATION WITH FORCING MECHANISMS
VERY SIMILAR TO WHAT WAS MENTIONED ABOVE...IS PROPAGATING THROUGH
SOUTHERN/SOUTHEASTERN MONTANA AT THIS TIME. THE HIGHEST POPS/LIKELY
CATEGORY...WILL JUST GRAZE THE FAR SOUTHWEST PER NAM/RAP OVERNIGHT.
SCATTERED RAIN SHOWERS SEEMS MORE APPROPRIATE...WITH SOME SNOW
POSSIBLY MIXED IN AT TIMES.
DEWPOINTS IN THE TURTLE MOUNTAINS HAVE NOW RISEN INTO THE LOWER
30S. DESPITE SOME CLEARING FROM TIME TO TIME...SATELLITE IMAGERY
AND SURFACE OBS STILL INDICATE ENOUGH CLOUD COVER UPSTREAM TO KEEP
TEMPERATURES ABOVE FREEZING OVERNIGHT. BELIEVE THE FROST ADVISORY
IS IN GOOD STANDING AND WILL NOT MAKE ANY CHANGES AT THIS TIME.
UPDATE ISSUED AT 618 PM CDT WED SEP 10 2014
THE LATEST VISIBLE SATELLITE IMAGERY AND SURFACE OBSERVATIONS SHOW
A CLOUDY SKY ACROSS WESTERN AND CENTRAL NORTH DAKOTA WITH THE
EXCEPTION OF RUGBY AND ROLLA WHERE A STRONGER NORTHEAST FLOW IS
ERODING A CLOUD SHIELD ADVANCING EAST FROM WESTERN NORTH DAKOTA.
THERE ARE MORE HOLES IN THE OVERCAST CONDITIONS ACROSS SOUTHEAST
SASKATCHEWAN AND WESTERN MANITOBA. THE CURRENT FROST ADVISORY AREA
LOOKS ON TRACK AT THIS TIME. WILL MONITOR FOR ADDITIONAL CLEARING
FARTHER WEST AND SEE HOW TEMPERATURES REACT THIS EVENING...GIVEN
DEWPOINTS ARE IN THE UPPER 20S IN THE TURTLE MOUNTAINS. THIS COULD
BECOME A BIGGER CONCERN WITH COLDER LOW TEMPERATURES IF THE SKY
GRID TRENDS CLEARER THAN EXPECTED WITH A CONTINUED NORTHEAST
WIND. HOWEVER AT THIS TIME...FEEL ENOUGH CLOUDS UPSTREAM WILL NEGATE
A POTENTIAL FREEZE WARNING IN THE NORTHEAST...BUT WILL MONITOR
THIS EVENING.
REPORTS OF SOME SNOW MIXED IN WITH THE RAIN AT BEACH LATE THIS
AFTERNOON...ALSO AT NEW ENGLAND AND IN AMIDON. SURFACE TEMPERATURE
ROUGHLY AT 36F FOR THIS MIX TO OCCUR. THIS IS ASSOCIATED WITH A
SHORTWAVE EJECTING OUT OF THE WEST. NORTHEAST WINDS IN CENTRAL
NORTH DAKOTA CONTINUE TO ERODE THE LEADING EDGE OF THIS AREA
SHOWERS. HOWEVER...AN ISOLATED MENTION FROM BISMARCK/MANDAN EAST
INTO THE SOUTHERN JAMES RIVER VALLEY IS WARRANTED PER CURRENT
REFLECTIVITY`S AND HIGH RESOLUTION SOLUTIONS OF THE HRRR AND RAP
WHICH SLIDES A WEAK AREA THROUGH THIS EVENING. MINOR ADJUSTMENTS
TO TEMPERATURES AND DEWPOINTS AS WELL AS POPS THIS EVENING. REST
OF FORECAST REMAINS ON TRACK.
UPDATE ISSUED AT 437 PM CDT WED SEP 10 2014
QUICK UPDATE TO EXPAND AN ISOLATED MENTION OF RAIN SHOWERS THROUGH
SOUTH CENTRAL NORTH DAKOTA THIS EVENING. LATEST BISMARCK AND
BOWMAN RADARS SHOWING AN AREA OF LIGHT RAIN SHOWERS MOVING EAST
OUT OF THE SOUTHWEST. A MID LEVEL CIRCULATION LOCATED IN THE WEST
WILL SLIDE EAST EARLY THIS EVENING...AND CONCUR WITH HIGHER
RESOLUTION MODELS OF THE RAP AND HRRR...THIS PRECIPITATION WEAKENS
BUT ALSO EXPANDS INTO SOUTH CENTRAL NORTH DAKOTA INCLUDING THE SOUTHERN
JAMES RIVER VALLEY BETWEEN 00Z AND 03Z.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 255 PM CDT WED SEP 10 2014
THE MAJOR FORECAST CHALLENGE WILL BE THE FROST POTENTIAL TONIGHT.
THE LATEST SHORT RANGE MODEL GUIDANCE CONTINUES TO PROG BOUNDARY
LAYER MOISTURE TO ERODE TO THE SOUTHWEST AS DRIER AIR GETS USHERED
IN FROM THE NORTHEAST. FURTHERMORE...BOUNDARY LAYER WINDS ARE
FORECAST TO WEAKEN TO AROUND 10 KNOTS TONIGHT AS HIGH PRESSURE
SETTLES INTO MONTANA. HOWEVER...THE LATEST GUIDANCE CONTINUES TO
PROG MID-LEVEL MOISTURE/CLOUDS (USING 850MB-500MB LAYER RH FIELDS)
TO STREAM OVER MOST OF WESTERN AND CENTRAL NORTH DAKOTA TONIGHT
AHEAD OF A SHORTWAVE ROTATING INTO MONTANA. THIS WOULD LIKELY
INHIBIT COOLING TEMPERATURES.
BALANCING WHERE THE CLEARING SKIES ARE FORECAST...WINDS WEAKENING
OVERNIGHT...AND BOUNDARY LAYER TEMPERATURES...THINK THE TURTLE
MOUNTAIN AREA WILL HAVE THE BEST CHANCE OF SEEING A FROST BETWEEN
09Z-14Z THURSDAY MORNING. AS A RESULT...ISSUED A FROST ADVISORY FOR
BOTTINEAU...ROLETTE...AND PIERCE COUNTIES FOR SAID TIME PERIOD.
TO THE SOUTHWEST...THERE WILL BE A CHANCE FOR A RAIN/SNOW MIX AFTER
MIDNIGHT. HOWEVER...ACCUMULATIONS SHOULD BE LIGHT.
FOR THURSDAY...DEEP MOISTURE AND ASSOCIATED PRECIP CHANCES WILL
CONTINUE TO PUSH SOUTH OF THE STATE AS HIGH PRESSURE BUILDS INTO THE
REGION. WELL BELOW NORMAL HIGHS ARE EXPECTED ONCE AGAIN WITH
READINGS RANGING FROM THE MID 40S SOUTHWEST TO THE MID 50S EAST.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 255 PM CDT WED SEP 10 2014
FOCUS IN THE LONG TERM WILL BE ON THE POTENTIAL FOR WIDESPREAD FROST
AND A FREEZE FRIDAY MORNING.
MODEL GUIDANCE CONTINUES TO SHOW LOWS IN THE UPPER 20S ACROSS THE
WEST AND LOWER 30S ELSEWHERE. WITH A LARGE SURFACE HIGH OVER THE
NORTHERN PLAINS WINDS WILL BE LIGHT. THE BIGGEST QUESTION WILL BE
HOW FAST CLOUDS CLEAR OUT. DEEP MOISTURE ACROSS THE STATE WILL BEGIN
TO CLEAR OUT QUICKLY AROUND 18 UTC THURSDAY...HOWEVER THE 12 UTC
MODEL GUIDANCE SHOWS A THIN LAYER OF LOW TO MID LEVEL MOISTURE
HANGING AROUND THROUGH 06 UTC FRIDAY.
REGARDLESS AT LEAST PATCHY FROST SEEMS LIKELY ACROSS CENTRAL AND
WESTERN NORTH DAKOTA. WIDESPREAD FROST IS LOOKING THE MOST LIKELY
ACROSS THE NORTHWEST AS CLOUD COVER WILL CLEAR FROM NORTH TO
SOUTH. THE NORTH WILL ALSO HAVE THE BEST OPPORTUNITY FOR A FREEZE AS
LOWS WILL MOSTLY BE BELOW FREEZING...ESPECIALLY NORTHWEST. AS FOR
THE SOUTH HAVE LIMITED THE WORDING FOR FROST AT AREAS FOR NOW AS
CLOUD COVER MAY STICK AROUND LONG ENOUGH TO PREVENT WIDESPREAD FROST
DEVELOPMENT. FOR THE SAME REASON THERE IS LESS OF A CHANCE OF A
FREEZE ACROSS THE SOUTH. TEMPERATURES WILL ALSO DROP LOW ENOUGH ON
SATURDAY MORNING ACROSS THE SOUTH...ESPECIALLY FOR THE
SOUTHWEST...FOR SOME PATCHY FROST.
FOR THE REMAINDER OF THE LONG TERM THE 12 UTC MODEL GUIDANCE
CONTINUES TO SHOW A MEAN TROUGH OVER THE U.S. THE 12 UTC GFS AND
ECMWF SHOW ANOTHER SHORT WAVE RIDING DOWN THE LEE OF THE CANADIAN
ROCKIES INTO THE NORTHERN PLAINS LATE SATURDAY INTO SUNDAY. MODELS
ARE NOT SHOWING MUCH PRECIPITATION WITH THIS SYSTEM AND THE
REMAINDER OF THE LONG TERM IS ALSO LOOKING MOSTLY DRY AND WARMER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1250 AM CDT THU SEP 11 2014
MVFR CEILINGS AT KDIK WILL CONTINUE THROUGH THE NIGHT...WITH
SCATTERED LIGHT RAIN SHOWERS POSSIBLY MIXED WITH SNOW. OTHERWISE
GENERALLY VFR STRATUS WILL PERSIST THROUGH THE NIGHT AND THROUGH
THE MORNING ACROSS WESTERN AND CENTRAL NORTH DAKOTA...BEFORE
SLOWLY CLEARING FROM NORTH TO SOUTH LATE THIS AFTERNOON AND INTO
THE EVENING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY FROM 4 AM TO 9 AM CDT THIS MORNING FOR NDZ004-005-
013.
&&
$$
UPDATE...AYD
SHORT TERM...TM
LONG TERM...MM
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1143 PM CDT WED SEP 10 2014
.UPDATE...
ISSUED AT 1143 PM CDT WED SEP 10 2014
TWEAKED TEMPS A BIT BUT WILL KEEP THE FROST HEADLINES GOING.
A FEW SPOTS IN THE EASTERN COUNTIES HAVE ALREADY DROPPED INTO THE
30S BUT WITH INCREASING CLOUDS THAT SHOULD SLOW DOWN A BIT.
NORTHWESTERN COUNTIES MAY NOT MAKE ADVISORY CRITERIA BUT WITH THE
POSSIBILITY OF A FEW BREAKS IN THE CLOUDS AM RELUCTANT TO END IT
EARLY. BUMPED UP POPS IN THE FAR SOUTHWEST AS THERE HAVE BEEN SOME
DECENT RADAR RETURNS ALTHOUGH REPORTS OF RAIN REACHING THE GROUND
HAVE BEEN HIT OR MISS.
UPDATE ISSUED AT 947 PM CDT WED SEP 10 2014
TEMPS CONTINUE TO BE THE MAIN QUESTION. MOST LOCATIONS HAVE STAYED
IN THE 40S...ALTHOUGH FOSSTON HAS DROPPED DOWN TO 37 WITH LESS
CLOUD COVER IN THAT AREA AND THAT SITES TYPICAL COLD BIAS. DEW
POINTS EARLIER THIS EVENING WERE IN THE UPPER 20S IN SOME
SPOTS...BUT THERE HAS BEEN AN UPWARD TREND AND CLOUDS CONTINUE TO
INCREASE FROM THE WEST. THERE COULD BE SOME BREAKS IN THE CLOUDS
AND LIGHT ENOUGH WINDS TO DROP A FEW SPOTS INTO THE MID TO LOW
30S. THE DEW POINTS ARE LOWEST IN THE NORTHWESTERN COUNTIES BUT
THE CLOUD COVER IS LESS IN THE NORTHEAST...SO THESE AREAS CONTINUE
TO BE MOST LIKELY TO SEE THE LOW TEMPERATURES. WILL KEEP THE FROST
ADVISORY GOING FOR NOW.
DOWN OVER THE SOUTHWESTERN COUNTIES...RADAR RETURNS HAVE BEEN
ENTERING THE AREA AS A WEAK SHORTWAVE PASSES THROUGH. NOT TOO MUCH
REACHING THE GROUND SO WILL KEEP POPS IN THE 20-30 PERCENT RANGE.
THE PRECIP SHOULD TAPER OFF AFTER MIDNIGHT.
UPDATE ISSUED AT 645 PM CDT WED SEP 10 2014
MADE A FEW MINOR TWEAKS TO POPS AS SHORT RANGE MODELS LIKE THE
HRRR AND THE RAP TREND TOWARDS BRINGING SOME SHOWERS FROM
SOUTHWESTERN ND INTO OUR FAR SOUTHWESTERN COUNTIES. NOT HUGELY
IMPRESSED WITH SIGNIFICANT PRECIP CHANCES...BUT INCLUDED A
ISOLATED MENTION IN THE FAR SOUTHWEST IN CASE SOME SPRINKLES MOVE
INTO RANSOM OR SARGENT COUNTIES. WILL HOLD ONTO FROST HEADLINES
AND CURRENT TEMPS FOR NOW AND TAKE A SECOND LOOK ONCE THE SUN
SETS.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 258 PM CDT WED SEP 10 2014
MAIN FORECAST CHALLENGE WILL BE FROST POTENTIAL THE NEXT FEW
NIGHTS. AS OF MID AFTERNOON SEEING MORE SUN THAN HAD EARLIER
ANTICIPATED. BASICALLY SEEING WEST TO EAST MID LEVEL FLOW WITH
SOME MID LEVEL CLOUDS DRIFTING OVER THE FA. MEANWHILE DRY
NORTHEAST WINDS CONTINUE TO ERODE THE LOWER CLOUDS OVER PORTIONS
OF THE NORTHERN AND EASTERN FA. WINDS ARE STILL PRETTY GUSTY BUT
THESE SHOULD BEGIN TO DECREASE THRU THE EVENING. SHOULD SEE THE
MOST DECREASE IN WINDS LATE...THEREFORE MUCH OF THIS FORECAST
HINGES ON CLOUD COVER. THINK THAT THERE WILL BE SOME CLOUD COVER
OVER THE AREA TONIGHT AND MAYBE MORE SO ACROSS THE SOUTH. WITH
TEMPS ALREADY SO COOL THINK THAT ALL IT WILL TAKE IS AN HOUR OR
SO WITH NO CLOUDS FOR TEMPS TO QUICKLY PLUMMET. THEREFORE DROPPED
LOWS A FEW MORE DEGREES IN THE EAST TO GO ALONG WITH THE EXPECTED
COOLER TEMPS IN THE NORTHWEST. WILL GO WITH A FROST ADVISORY FOR
BOTH AREAS...ESSENTIALLY THE NORTHWEST EDGE OF THE FA AND THE
EASTERN EDGE. IN BETWEEN MAY BE CLOSE AND WILL LET THE EVENING
SHIFT KEEP AN EYE ON THAT. SEEMS LIKE WE TRADITIONALLY MISS THE
FIRST FROST BECAUSE IT IS SO SPOTTY. THIS MAY BE THE CASE THIS
TIME TOO...WITH SOME COLD SPOTS AND FROST WITH SOME WARMER SPOTS
CLOSE BY. WILL CONTINUE TO SEE THE WESTERLY MID LEVEL FLOW ON THU
SO WILL STICK WITH MORE CLOUDS TO THE SOUTH AND LESS NORTH...BUT
AGAIN A TOUGH CALL. MORE OF THE AREA WILL PROBABLY BE UNDER THE
GUN THU NIGHT BUT THINK AREAS ALONG AND NORTH OF HIGHWAY 2 MAY
HAVE THE BEST CHANCE OF FROST.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 258 PM CDT WED SEP 10 2014
SFC HIGH WILL DRIFT SOUTH OF THE AREA FOR FRI INTO SAT. THERE MAY
STILL BE SOME FROST POSSIBLE FRI NIGHT BUT RETURN SOUTH-SW FLOW
WILL DEVELOP. THEREFORE WIND AND CLOUDS WILL REMAIN THE MAIN
CHALLENGE. KEPT A DRY FORECAST SAT ALTHOUGH SEVERAL MODELS SHOW
ANOTHER SFC LOW IN THE NORTHWEST FA WITH A LITTLE LIGHT PCPN
AROUND IT.
LONG TERM MODELS IN SIMILAR AGREEMENT WITH UPPER WAVE EXTENDING
ACROSS S CNTRL CANADA SUN NIGHT...AND POSITION OF SFC HIGH IN MUCH
BETTER AGREEMENT (THAN YESTERDAYS 12Z RUNS) BETWEEN THE GFS/ECMWF.
BOTH MODELS INDICATING MOSTLY DRY WX AS SFC FRONT MOVES ACROSS MB
AND CLIPS THE NORTHERN VALLEY. CONSALL DOES SHOW LOW POPS OVER
NORTHEAST AS BOTH MODELS HAVE PRECIP OVER NE MN SAT NIGHT. SFC HIGH
THEN DOMINATES AREA FOR MON AND TUE OF NEXT WEEK AS DRY AND COOL WX
CONTINUES. RETURN FLOW SETS UP ON TUE...CAUSING A MILD WARMING TREND
BUT DID REMOVE SPOTTY LOW POPS PRODUCED BY CONSALL AS BOTH GFS AND
ECMWF ARE DRY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1143 PM CDT WED SEP 10 2014
VFR CONDITIONS WILL CONTINUE THROUGHOUT THE PERIOD WITH MID AND
HIGH LEVEL CLOUDS. TOMORROW THE CIGS COULD DROP TO THE LOWER END
OF VFR BUT ARE NOT EXPECTED TO GO ANY LOWER. NORTH WINDS WILL
CONTINUE BUT SHOULD BE UNDER 12 KTS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...FROST ADVISORY FROM 4 AM TO 9 AM CDT THURSDAY FOR NDZ006-007-014.
MN...FROST ADVISORY FROM 4 AM TO 9 AM CDT THURSDAY FOR MNZ005-006-008-
009-013>017-023-024.
&&
$$
UPDATE...JR
SHORT TERM...GODON
LONG TERM...GODON/SPEICHER
AVIATION...JR
AREA FORECAST DISCUSSION
NWS TULSA OK
1154 PM CDT WED SEP 10 2014
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE TO BE POSSIBLE
ACROSS MAINLY SOUTHEAST OKLAHOMA AND NORTHWEST ARKANSAS TONIGHT
INTO THURSDAY MORNING AS A COLD FRONT MOVES THROUGH. BEHIND THE
FRONT...MVFR TO POSSIBLE PERIODS OF IFR CEILINGS ARE EXPECTED TO
OVERSPREAD THE REGION AND REMAIN INTO THE AFTERNOON HOURS. PARTS
OF NORTHEAST OKLAHOMA INTO FAR NORTHWEST ARKANSAS COULD LIFT BACK
TO VFR FOR A FEW HOURS BUT THEN DROP BACK TO MVFR THURSDAY
EVENING. PRECIP CHANCES WILL AGAIN BE POSSIBLE THURSDAY AFTERNOON
AND EVENING AND WILL CARRY PROB30 GROUPS FOR MLC/FSM AND HOLD OFF
FOR NOW ON ADDITIONAL PRECIP MENTIONS ELSEWHERE.
&&
.PREV DISCUSSION... /ISSUED 911 PM CDT WED SEP 10 2014/
..UPDATE...
DISCUSSION...
OUN SOUNDING CONTINUES TO SHOW RELATIVELY MOIST SOUTHWEST WINDS
ABOVE THE FRONT. THIS COULD SUPPORT ELEVATED PRECIPITATION AND
CONVECTION THROUGH THE NIGHT. RAP AND HRRR APPARENTLY SEE THIS AND
ALSO DEVELOP PRECIPITATION LATER IN THE NIGHT. BEST BET IS AGAIN
OVER WEST CENTRAL ARKANSAS INTO SOUTHEAST OKLAHOMA...GENERALLY
ALONG AND SOUTH OF I-40. LOWER CHANCES WILL EXTEND NORTHWARD...BUT
NOT ALL THE WAY TO THE KANSAS BORDER. WILL KEEP CHANCES IN THE
FORECAST FOR FAR NORTHWEST ARKANSAS ALSO.
LIGHT SHOWERS MOVING ACROSS PARTS OF NORTHEAST OK NOW. OTHER
SHOWERS AND ISOLATED THUNDERSTORM REDEVELOPING ALONG I-40 FROM
CHECOTAH TO THE WEST OF OKEMAH.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 61 76 61 65 / 40 10 30 50
FSM 70 75 66 71 / 70 50 50 70
MLC 66 75 66 68 / 70 50 60 60
BVO 58 74 58 66 / 20 10 20 40
FYV 63 73 60 67 / 60 40 40 60
BYV 62 72 58 66 / 60 30 40 50
MKO 63 77 63 66 / 50 20 40 60
MIO 59 73 57 66 / 20 10 20 40
F10 63 76 62 65 / 50 20 40 60
HHW 71 80 69 74 / 60 60 70 60
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
AVIATION...20
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1244 AM CDT THU SEP 11 2014
.UPDATE...
AVIATION DISCUSSION HAS BEEN UPDATED.
A QUICK MOVING SHORT WAVE TROUGH WAS BRINGING SOME LIGHT RAIN SHOWERS
TO THE REGION THIS EVENING. THIS WILL MOVE ON TO THE EAST AFTER MIDNIGHT
WHILE NEW DEVELOPMENT MOVES INTO THE WEST AND SOUTHWEST PARTS OF
THE CWA WITH THE MAIN UPPER LOW PRESSURE TROUGH. ADJUSTED POPS FOR
THE NIGHT...MAINLY ACROSS THE NORTHERN CWA. UPDATED FORECAST.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT
CLOUDY AND COLD IS THE STORY ACROSS THE REGION THIS AFTERNOON. IN
FACT...SOME LOCATIONS WILL LIKELY SET RECORDS FOR THE COLDEST
HIGH TEMPERATURE EVER RECORDED ON THIS DATE. CWA IS CURRENTLY DRY
BUT WATCHING THE BEGINNINGS OF THE NEXT SYSTEM MOVING ACROSS
NORTHWEST SD. TREND FOR TONIGHT WILL BE FOR PRECIP TO MAINLY
AFFECT WESTERN AND CENTRAL SD...AND MAY EVEN GET COLD ENOUGH LATE
TONIGHT AND EARLY THURSDAY MORNING TO ALLOW FOR A RAIN/SNOW MIX
ACROSS THE FAR NORTHWEST CWA. TARGET AREA FOR ACCUMULATING SNOW
THOUGH STILL REMAINS OVER FAR WESTERN SD AND THE BLACK HILLS. WILL
HAVE TO WATCH CLOUD COVER TRENDS OVERNIGHT ACROSS THE
NORTHERN/NORTHEAST CWA AS CIGS HAVE THINNED AND HAVE EVEN REVEALED
SOME HOLES. RAP MODEL 925-850MB RH SHOWS THIS DRIER AREA
NICELY...AND BRINGS IN OVER THE NORTHERN COUNTIES LATER TONIGHT.
IF ANY BREAKS OR THINNING OCCUR...TEMPS COULD FALL PRETTY NICELY.
BUT OVERALL...THE ABUNDANCE OF MID AND HIGH CLOUDS WITH THE NEXT
APPROACHING WAVE...AND THE OVERALL WINDS STAYING UP A TOUCH SHOULD
PREVENT THE BOTTOM FROM FALLING OUT ON TEMPS.
ATTENTION THEN TURNS TO THURSDAY NIGHT AND FRIDAY MORNING AND THE
POTENTIAL FOR FROST. MODELS CONTINUE TO SHIFT PRECIP AND CLOUDS A
BIT FURTHER SOUTH AND EAST DURING THIS TIME...A BIT QUICKER THAN
PREVIOUS RUNS...AND THE PREVIOUSLY SLOWER EC IS NOW COMING AROUND
TO THE FASTER SOLUTIONS OTHER MODELS HAVE BEEN SHOWING. THIS MEANS
A BETTER POTENTIAL FOR FROST CONDITIONS AND TEMPS IN THE LOW TO
MID 30S OVER A GOOD PORTION OF THE CWA. INSERTED FROST INTO THE
GRIDS ALONG AND WEST OF THE JAMES VALLEY AND COULD VERY WELL BE
HEADING TOWARDS A FROST ADVISORY AT SOME POINT. IT WILL ALL DEPEND
ON HOW MUCH CLOUD COVER LINGERS OVER THE AREA...THE CLEARER THE
SKIES THE BETTER THE TEMPS WILL FALL.
FOR FRIDAY NIGHT AND SATURDAY...MODELS SEEM TO BE NUDGING THE HIGH
CENTER TO THE EAST A TAD QUICKER. WHAT THIS MEANS IS THAT A
SLIGHTLY STRONGER GRADIENT SETS UP FRIDAY NIGHT WITH SOUTH WINDS
PICKING UP. WHETHER OR NOT THESE WINDS ARE STRONG ENOUGH ALONG AND
EAST OF THE JAMES VALLEY TO PREVENT TEMPS FROM REACHING THE LOW TO
MID 30S IS DOUBTFUL. WEST OF THERE...PROBABLY YES. CANNOT RULE OUT
FROST FRIDAY NIGHT/SATURDAY MORNING EITHER...BUT BEST POTENTIAL
HERE WILL BE ACROSS THE EASTERN CWA.
.LONG TERM...SATURDAY THROUGH WEDNESDAY
NOT MUCH CHANGE IN THE EXTENDED FROM 24 HOURS AGO. 12Z MODEL
SOLUTIONS POINT TO A BIT OF WARMING ON SATURDAY OUT AHEAD OF AN
APPROACHING COLD FRONT. ANOTHER SURFACE HIGH PRESSURE SYSTEM
BUILDS DOWN FOR SUNDAY AND MONDAY...BUT THEN SHIFTS SOUTH AND EAST
OF THE AREA...ALLOWING FOR RETURN FLOW WARMING WINDS TUESDAY AND
WEDNESDAY. PRECIPITATION CHANCES REALLY ARE FEW AND FAR BETWEEN IN
THE OUT PERIODS...WITH THE "BEST" CHANCES FOR A FEW RAIN
SHOWERS SHOWING UP SUNDAY AFTERNOON/EVENING BEHIND THIS COLD
FROPA.
&&
.AVIATION...
06Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
A QUICK MOVING SHORT WAVE TROUGH WILL BRING SOME LIGHT RAIN
SHOWERS TO ATY INTO THE EARLY MORNING HOURS. OTHERWISE...LIFT
FROM THE MAIN UPPER LOW PRESSURE AREA DROPPING IN FROM THE NORTHWEST
TONIGHT AND THURSDAY WILL BRING SHOWERS INTO THE PIERRE AREA THROUGH
THURSDAY MORNING. EXPECT MOST OF THE SHOWERS TO REMAIN AWAY FROM
MBG...ABR AND ATY. CEILINGS ARE EXPECTED TO BE MAINLY VFR FOR MBG
...ABR AND ATY THROUGH THE PERIOD...EXCEPT FOR PIR WHERE THEY SHOULD
BE MAINLY MVFR.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...MOHR
SHORT TERM...TMT
LONG TERM...DORN
AVIATION...TDK
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
358 AM CDT THU SEP 11 2014
.DISCUSSION...
SURFACE COLD FRONT MADE SOME MORE PROGRESS EARLIER TONIGHT BEFORE
LOOSING STEAM OVER THE LAST COUPLE OF HOURS. AS OF CURRENT THE
FRONT WAS LOCATED JUST NORTH OF THE DALLAS/ FORT WORTH AREA. A 0Z
500 MB HAND ANALYSIS REVEALED A POTENT SHORTWAVE DIVING SOUTH
OVER MONTANA. AT 250MB RIDGING HAS STARTED TO FLATTEN AS A TROUGH
AXIS PUSHES IN FROM THE WEST. FOR TODAY MODELS ARE SHOWING A BIT
MORE COVERAGE THAN PREVIOUSLY ADVERTISED. CURRENT PWAT VALUES...
COURTESY OF GPS MET SITE... ARE AROUND 1.60". GFS FORECAST
SOUNDINGS FOR THIS AFTERNOON SHOW PWAT VALUES AROUND 1.7" WITH K
INDEX VALUES NEAR 30 WHILE THE NAM IS SLIGHTLY MORE AGGRESSIVE.
THE RIDGE SHOULD CONTINUE TO FLATTEN THIS AFTERNOON SO WILL LEAN
TO THE SLIGHTLY MORE AGGRESSIVE NAM. HIGH RES MODELS ALSO SUPPORT
THIS WITH CHANCE COVERAGE ALONG THE COAST. THE FRONT SHOULD REMAIN
NORTH OF THE AREA THIS AFTERNOON BUT THE RAP IS DEVELOPING PRECIP
ALONG THE FRONT AND PUSHING IT INTO OUR NORTHERN ZONES THIS AFTERNOON.
THIS EVENING INTO FRIDAY SOME CONVECTION COULD MAKE IT INTO OUR
NORTHERN ZONES BEFORE DISSIPATING. FRIDAY MORNING A TROPICAL WAVE
CURRENTLY LOCATED NEAR FLORIDA WILL APPROACH THE MEXICAN COAST
LINE. AS THE TROPICAL WAVE MOVES WEST IT WILL BRING VERY MOIST AIR
WITH IT. PWATS SURGE TOWARDS 2.20" FRIDAY AFTERNOON INTO SATURDAY.
AT THE SAME TIME THE FRONT CURRENTLY NORTH OF DALLAS/ FORT WORTH
WILL FINALLY MOVE INTO THE AREA. UPPER LEVEL SUPPORT FOR THIS
SYSTEM IS WEAK THOUGH. THE SHORTWAVE CURRENTLY DIVING SOUTH IN
MONTANA WILL QUICKLY START TO PULL TO THE EAST FRIDAY WHICH WILL
HELP TO STALL AND WASH OUT THE FRONT OVER OUR AREA FRIDAY EVENING
INTO SATURDAY MORNING. RAIN CHANCES WILL QUICKLY START TO RISE
FRIDAY AS THE WAVE APPROACHES. LIFT WILL COME FROM THE SURFACE
BOUNDARY AND SPEED CONVERGENCE AT 850MB. GIVEN VERY HIGH MOISTURE
VALUES AND LIFT RAIN LOOKS LIKELY FRIDAY EVENING INTO SATURDAY.
OMEGA VALUES FROM BOTH THE GFS AND NAM ALSO SUPPORT THIS. AS OF
CURRENT IT LOOKS THAT RAIN WILL START FRIDAY MORNING OVER THE
WATERS (IN ASSOCIATION WITH THE APPROACHING TROPICAL WAVE) AND
JUST NORTH OF THE AREA (IN ASSOCIATION WITH THE FRONT). RAIN WILL
THEN MOVE INLAND ALONG A SEA BREEZE AND POSSIBLY COLLIDE WITH ON
GOING SHOWERS AND THUNDERSTORMS WITH THE SURFACE FRONT TO THE
NORTH. THE EXACT LOCATION OF THE FRONT AND EXTENT OF PRECIPITATION
OVER THE WATERS COULD GREATLY INFLUENCE THE EVENTUAL DISTRIBUTION
OF RAINFALL. WITH THE WEAK STEERING FLOW THE CHANCE FOR HEAVY
RAIN REMAINS POSSIBLE FRIDAY AFTERNOON INTO SATURDAY MORNING.
ABOVE AVERAGE MOISTURE VALUES ARE EXPECTED TO REMAIN OVER THE AREA
THROUGH THE WEEKEND ALLOWING THE CHANCE OF RAIN TO CONTINUE.
MODELS DUE STRUGGLE ON HOW TO HANDLE THE REMNANT ENERGY OF THE
WAVE THOUGH AS IT MOVES INTO MEXICO. IN GENERAL MODELS MOVE THE
ENERGY NORTH AROUND A WEAK UPPER LEVEL RIDGE AND PICK IT BACK UP
IN THE FLOW. THE NAM MOVES PIECES OF POSITIVE VORTICITY OVER OUR
AREA SATURDAY EVENING WHILE THE GFS KEEPS THE ENERGY WEST OF US.
WHERE THIS LEFTOVER ENERGY MOVES NORTH WILL AFFECT WHERE THE
GREATEST CHANCES OF RAIN WILL BE SATURDAY INTO SUNDAY. BY NEXT
WEEK THE UPPER LEVEL FLOW WILL AMPLIFY A BIT OVER THE EASTERN
UNITED STATES ALLOWING MID LEVEL WINDS TO TURN FROM THE NORTHWEST
OVER SOUTHEAST TEXAS. THIS WILL ALSO ALLOW UPPER LEVEL
DISTURBANCES TO MOVE OVER THE AREA. THE BEST CHANCES OF RAIN WILL
BE IN THE AFTERNOON OF EACH DAY NEXT WEEK THANKS TO DAY TIME
HEATING. HAVE TRENDED POPS UP IN THE AFTERNOON FOR NEXT WEEK TO
ACCOUNT FOR THIS. 23
&&
.MARINE...
TYPICAL SUMMER LIKE PATTERN TODAY WITH ISO/SCT PRECIP IN COASTAL
WATERS IN THE MORNING HOURS, LIGHT-MODERATE SE WINDS AND LOW SEAS.
ERLY WAVE IN THE GULF WILL TRANSPORT INCREASED MOISTURE LEVELS INTO
THE WATERS LATER TONIGHT LEADING TO MORE AREAL PRECIP COVERAGE FRI
MORNING. AS THE WAVE APPROACHES THE WESTERN GULF COASTLINE FRI NIGHT
& SATURDAY...LOOK FOR WINDS TO INCREASE, BECOME MORE ERLY AND SEAS
TO BUILD. MAY NEED CAUTION FLAGS DURING THIS TIME. MODERATE ENE FLOW
AND RAIN CHANCES SHOULD PERSIST THRU THE WEEKEND AS GRADIENT
TIGHTENS NEAR THE COAST COMPLIMENTS OF A FRONTAL BOUNDARY LINGERING
IN THE REGION. 47
&&
.AVIATION...
HIGHER MOISTURE LEVELS HUGGING THE COAST WILL LEAD TO ISO/SCT PRECIP THERE
AND IN THE COASTAL COUNTIES THRU LATE MORNING. IT SHOULD CREEP INLAND TODAY
WITH DAYTIME HEATING AND EXPAND INTO METRO TAF SITES FROM LATE MORNING-LATE
AFTN. INCLUDED SOME VCSH`S FOR NOW. FRONTAL BOUNDARY MOVING INTO N TX SHOULD
PROVIDE A FOCUS FOR SOME TSRA LATER TODAY BUT SUSPECT MOST WILL REMAIN N OF CLL
THRU THE TAF PERIOD SO NO MENTION THERE YET. DO ANTICIPATE A DEEPER SURGE OF
MOISTURE TO MOVE INTO THE COASTAL WATERS PRIOR TO SUNRISE FRI AND EXPECT FAIRLY
GOOD CHANCES OF PRECIP S OF I-10 BETWEEN 10-18Z FRI...FOLLOWED BY MORE COVERAGE
FRI AFTN (BEYOND 12Z TAF). OUTSIDE OF PRECIP MAINLY VFR CONDITIONS SHOULD
PREVAIL. 47
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 97 75 90 71 85 / 20 30 60 60 40
HOUSTON (IAH) 95 77 91 73 86 / 30 30 60 60 50
GALVESTON (GLS) 91 82 90 79 86 / 20 30 60 60 60
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...23
AVIATION/MARINE...47
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1150 PM CDT WED SEP 10 2014
.DISCUSSION...
SEE THE 06Z AVIATION DISCUSSION BELOW.
40
&&
.AVIATION...
A COUPLE OF ITEMS TO COVER FOR THIS FORECAST PERIOD. THE FIRST
WILL BE THE POSSIBILITY FOR MVFR CONDITIONS TONIGHT THROUGH 14Z
THURSDAY MORNING. BEST CHANCES APPEAR TO BE AT KCLL...KUTS...AND
KCXO. THE LATEST NAM12 SHOWED A LOW-LEVEL JET OVERHEAD OF KCLL
WHICH SHOULD TRANSLATE TO A LOW CLOUD DECK FORMING BETWEEN 08Z AND
10Z AT THE THREE SITES.
THE SECOND ITEM REGARDS RAIN CHANCES. DECENT MOISTURE ADVECTION
WAS HELPING FORM ISOLATED SHOWERS IN THE GULF AT 0430Z. THE HIGH
RESOLUTION AND NAM12 MODELS ALL INDICATE THESE MAY WORK THEIR WAY
INTO KGLS AFTER 09Z. THE NAM12 WEAKENS THE SURFACE PRESSURE
GRADIENT AS IT BUILDS A HIGH PRESSURE RIDGE INTO THE COASTAL AREAS
FROM THE EAST. HOWEVER...THE MOISTURE INCREASES DURING THE
AFTERNOON PERIOD WITH PW/S REACHING TO BETWEEN 1.9 AND 2.2 INCHES.
WITH THIS IN MIND...FELT THERE WAS A DECENT CHANCE FOR ISOLATED
SHOWERS TO AFFECT THE INLAND SITES DURING THE AFTERNOON FROM KLBX
TO KCXO. FOR NOW WILL GO WITH A VICINITY MENTION.
LASTLY...DECENT RAIN CHANCES ARE LOOKING TO OCCUR WITH THE ADVANCE
OF A COLD FRONT INTO SE TX ON FRIDAY. THE FORECAST COVERAGE AND
TIMING BY THE MODELS IS TOO BROAD AT THIS TIME TO PINPOINT FOR
THE AVIATION SITES. FOR NOW THE BEST CHANCES LOOK TO BEGIN FROM
HOUSTON TO THE COAST SOMETIME LATE MORNING ON FRIDAY.
40
&&
.PREV DISCUSSION... /ISSUED 952 PM CDT WED SEP 10 2014/
UPDATE...
SEE EVENING UPDATE.
DISCUSSION...
AT 8 PM...A COLD FRONT EXTENDED FROM FT SMITH TO NEAR SHERMAN TO
BIG SPRINGS. AT 850 MB...A TROUGH OF LOW PRESSURE EXTENDED NORTH
TO SOUTH ACROSS WEST TEXAS WITH DEEP 850 MOISTURE OVER OK...AR
AND NE TX. ANOTHER WEAK TROUGH WAS NOTED BETWEEN OKC AND DFW. 850
TEMPS WERE -3 C AT GLASGOW MT WHICH IS PRETTY COOL FOR THIS TIME
OF YEAR. A POOL OF DEEPER 700 MB MOISTURE WAS LOCATED OVER N TX
AND S OK WITH A WEAK TROUGH OVER SW TX. AT 250 MB...A BROAD TROUGH
WAS LOCATED OVER THE CENTRAL PLAINS WITH UPPER LEVEL RIDGING
EXTENDING FROM THE SOUTHERN APPALACHIANS ACROSS COASTAL TEXAS.
00Z MODEL RUNS ARE JUST COMING IN BUT SHORT TERM GUIDANCE IS
TRENDING WETTER FOR THURSDAY. THE RAP IN PARTICULAR BRINGS IN
SLIGHTLY HIGHER MOISTURE EARLY THURSDAY MORNING COURTESY OF A
BROAD EASTERLY WAVE THAT EXTENDS FROM THE MS COAST TO THE MEXICAN
COAST. 00Z SOUNDINGS CAME IN DRY AND GPS MET NETWORK SHOWS PW
VALUES AROUND 1.6 INCHES WHICH IS ON THE DRY SIDE FOR EARLY SEPT.
YET THE RAP AND TO A LESSER EXTENT THE HRRR...ARW AND TEXAS TECH
WRF SHOW SHRA/TSRA DEVELOPING BY 13Z AND SPREADING INLAND. THE RAP
ALSO BRINGS A WIND SHIFT TO THE COLLEGE STATION AREA AROUND 18Z.
PRESSURE RISES BEHIND THE FRONT ARE NOT THAT IMPRESSIVE SO PREFER
THE NAM 12 FOR FRONTAL TIMING. ADDED POPS FOR LATE TONIGHT ALONG
THE COAST AND ADDED MORNING POPS FOR AREAS SOUTH OF I-10. NEW
ZONES OUT BY 10 PM. 43
CLIMATE...
CRUNCHING SOME NUMBERS TONIGHT ON RAINFALL DEFICITS ACROSS THE
AREA. GALVESTON IS OVER 75 INCHES BELOW NORMAL SINCE JAN 1 2009.
HOBBY AIRPORT IS NOT THAT FAR BEHIND AND IS 65 INCHES BELOW NORMAL
SINCE 2009. HOPEFULLY RAIN THIS WEEKEND WILL PUT A DENT INTO SOME
THESE NUMBERS.
HURRICANE CARLA MADE LANDFALL ON SEPT 11 1961. IT`S THE LAST CAT 4
TO AFFECT THE UPPER TEXAS COAST. CARLA WAS BRIEFLY A CAT 5 OVER
THE GULF. 43
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 77 97 75 90 71 / 10 20 30 60 60
HOUSTON (IAH) 77 96 77 91 74 / 10 20 30 60 60
GALVESTON (GLS) 83 91 82 90 79 / 20 20 30 60 60
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...43
AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS ALBANY NY
736 AM EDT THU SEP 11 2014
.SYNOPSIS...
LOW PRESSURE IN EASTERN CANADA WILL DRIVE A COLD FRONT ACROSS THE
REGION THIS AFTERNOON. AHEAD OF THIS FRONT WILL BE SCATTERED SHOWERS
AND PERHAPS A THUNDERSTORM...MAINLY SOUTH OF ALBANY. BEHIND THIS
FRONT WILL COME THE COOLEST AIR MASS SINCE LATE MAY BY FRIDAY. A
DISTURBANCE MIGHT BRING A ROUND OF SHOWERS ON SATURDAY FOLLOWED BY
MORE COOL DRY WEATHER SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 630 AM EDT...SCATTERED MAINLY LIGHT SHOWERS WERE WORKING INTO
MUCH OF THE AREA. THIS BATCH WILL LEAVE BUT OTHERS WILL THROUGHOUT
THE DAY. LOW PRESSURE WAS WORKING THROUGH SOUTHERN ONTARIO DRAGGING
AA COLD FRONT INTO WESTERN NEW YORK.
FOR THIS UPDATE...JUST INCREASED HOURLY POPS A BIT THIS MORNING (DUE
TO THE SCATTERED SHOWERS MOVING QUICKLY EAST). OTHERWISE VERY LITTLE
TO TWEAK OTHER THAN THAT.
THE LATEST RUC13 INDICATED LITTLE OR NO INSTABILITY SO WE KEPT ANY
MENTION OF THUNDER OUT OF THE FORECAST THROUGH EARLY MORNING.
TEMPERATURES WERE QUITE MILD DUE TO AN INCREASE IN CLOUDS...AND A
PERSISTENT SOUTHERLY BREEZE ON THE WARM SIDE OF THE LOW
PRESSURE...HOLDING MAINLY IN THE 60S.
THE AFOREMENTIONED COLD FRONT ASSOCIATED WITH THE LOW PRESSURE WILL
MOVE STEADILY ALONG AND WORK INTO THE SOUTHERN ADIRONDACKS AND THE
MOHAWK VALLEY EARLY THIS AFTERNOON...THE CAPITAL REGION AND
SURROUNDING AREAS LATE AFTERNOON...AND THE MID HUDSON VALLEY AND
NORTHWESTERN CONNECTICUT BY EARLY EVENING.
DUE TO VERY LIMITED INSTABILITY WE ONLY MENTION A SLIGHT CHANCE OF
THUNDERSTORM FROM THE CAPITAL REGION NORTHWARD. FURTHER SOUTH...WITH
A LITTLE MORE INSTABILITY...WE DID MENTION A CHANCE OF
THUNDERSTORMS. IT IS REMOTELY POSSIBLE THAT ANY THUNDERSTORM IN THIS
AREA COULD CONTAIN SOME GUSTY WINDS AS THE OVERALL WIND FIELD (BULK
SHEAR) INCREASES TO ABOUT 35-40KTS. HOWEVER...THE THREAT APPEARED
LOW ENOUGH NOT TO MENTION IN THE GRIDS OR CERTAINLY ENHANCED WORDING
AT THIS TIME.
PWAT VALUES LOOK TO INCREASE TO ABOUT 2 INCHES...BUT THIS LOOKS TO
HAPPEN THIS MORNING. THE H20 WATER VAPOR LOOP ALREADY INDICATED A
MID LEVEL DRY PUNCH QUICKLY WORKING INTO WESTERN NEW YORK STATE.
THIS DRY PUNCH WILL ALLOW PWATS TO DROP QUICKLY THIS
AFTERNOON...EVEN AHEAD OF THE FRONT. THEREFORE THE BEST FORCING
(WHICH IS GOING TO WELL NORTH)...WILL NOT LINE UP WITH THE BEST
PWATS AND PASSAGE OF THE COLD FRONT.
THERE WILL BE PLENTY OF CLOUDS TODAY WITH PERHAPS A FEW BREAKS OF
AFTERNOON SUNSHINE. EVEN SO...TEMPERATURES COULD SPIKE A LITTLE
AHEAD OF THE FRONT. WE EXPECT HIGHS NEAR 80 IN THE MID HUDSON VALLEY
AND LOWER LITCHFIELD COUNTY...UPPER 70S AROUND ALBANY. FURTHER NORTH
AND WEST WHERE THE COLD FRONT WILL BE FIRST TO COME THROUGH...HIGH
TEMPERATURES WILL BE HELD TO BETWEEN THE UPPER 60S TO MID 70S.
A GUSTY SOUTH WIND PREVAIL TODAY 10 TO 20 MPH...SHIFTING TO THE WEST
BY LATE IN THE DAY ONCE THE COLD FRONT MOVES THROUGH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
THE COLD FRONT WILL BE FINISHING ITS SWEEP THROUGH OUR AREA THIS
EVENING TAKING ANY LEFTOVER SHOWERS WITH IT.
THEN...A COOL CANADIAN AIR MASS WILL BE USHERED IN TONIGHT ON
SOMEWHAT GUSTY NORTH OR NORTHWEST WINDS. THE SKY WILL CLEAR AND
TEMPERATURES WILL DIP DOWN TO AROUND 50 FROM ALBANY SOUTH AND EAST.
FURTHER NORTHWEST AND WEST...THEY WILL DIVE INTO THE 40S...AND EVEN
TOUCH THE UPPER 30S ACROSS OUR ADIRONDACKS.
FRIDAY LOOKS TO FEATURE A GOOD DEAL OF SUNSHINE (MIXING WITH FAIR
WEATHER STRATO-CUMULUS) AND TEMPERATURES BELOW NORMAL. H850
TEMPERATURES LOOK TO DROP TO BETWEEN +5C NORTHWEST TO +9C SOUTHEAST
ACROSS OUR REGION. THIS WILL TRANSLATE TO HIGH TEMPERATURES MAINLY
IN THE 60S THROUGH OUR REGION...PERHAPS TOUCHING 70 FROM
POUGHKEEPSIE...BUT ONLY 50S ACROSS THE ELEVATED TERRAIN NORTH OF
ALBANY...MAKING IT FEEL AUTUMNAL.
HIGH PRESSURE WILL CREST NORTH OF THE REGION EARLY FRIDAY NIGHT
BEFORE RETREATING TO THE CANADIAN MARITIMES. A COOL NIGHT IS IN
STORE BUT NOT AS COOL AS WOULD HAVE BEEN. WHILE THE NIGHT WILL START
CLEAR...CLOUDS SHOULD INCREASE DUE TO WARM AIR ADVECTION AS A POTENT
DISTURBANCE APPROACHES FROM THE OHIO VALLEY. OVERNIGHT LOWS WILL
RANGE FROM THE UPPER 40S SOUTHEAST OF ALBANY...DOWN TO THE UPPER 30S
ACROSS THE ADIRONDACKS. IF IT WERE TO GET ANY COLDER THERE...SOME
FROST WOULD BE POSSIBLE. WE WILL MONITOR THAT POTENTIAL BUT FOR
NOW...WE ARE FORECASTING TEMPERATURES TO REMAIN JUST ABOVE THE FROST
THRESHOLD.
THEN ON SATURDAY...AS THE AFOREMENTIONED DISTURBANCE APPROACH...IT
LOOKS AS OF SURFACE LOW PRESSURE WILL FORM AT THE TRIPLE POINT OF
THE WARM FRONT/COLD FRONT INTERFACE TO OUR SOUTHEAST. AT THIS POINT
SHOWERS APPEARS TO BE A GOOD BET. IF SURFACE LOW PRESSURE DEVELOPS
EVEN QUICKER...WE WOULD BE LOOKING AT A STEADY RAIN. FOR NOW...WILL
CALL IT SHOWERS...BUT EITHER WAY...SATURDAY LOOKS LIKE A
CLOUDY...DAMP DAY WITH HIGHS RANGING ONLY FROM THE MID 50S NORTHWEST
TO UPPER 60S SOUTHEAST OF ALBANY.
THE DISTURBANCE LOOKS TO MOVE QUICKLY EAST SATURDAY NIGHT...FOLLOWED
BY PARTIAL CLEAR AND ANOTHER CANADIAN HIGH PRESSURE BRINGING A
RE-NEWED SHOT OF COOL BUT DRY TO CLOSE OUT THE WEEKEND.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
THE LONG TERM PORTION OF THE FORECAST WILL FEATURE A BROAD UPPER
TROUGH ACROSS THE EASTERN 2/3RDS OF NOAM. THIS WILL KEEP
TEMPERATURES A BIT BELOW NORMAL ALONG WITH NEAR TO BELOW NORMAL
PRECIPITATION. THE NEXT APPRECIABLE CHANCE FOR WET WEATHER IS LATE
MONDAY NIGHT INTO TUESDAY AS THE NEXT PV ANOMALY IS PROGGED TO TRACK
ACROSS THE GREAT LAKES REGION AND NORTHEAST CONUS. QPF/S FROM THE
GLOBAL MODELS DIFFER AS THE GFS IS THE MOST AGGRESSIVE /LESS QPF/
WITH TRACK OF THIS WAVE. MEANWHILE THE ECMWF CONTINUES TO SUGGEST A
COASTAL WAVE DEVELOPMENT WHICH SLOWS DOWN THE FORWARD PROGRESS AND
KEEPS THE PRECIP LINGER LONGER /AND HIGHER QPF/. THE GGEM IS
FURTHER SOUTH WITH LIGHTER AMOUNTS AS MAIN WAVE MOVES OFF THE
CAROLINA/VIRGINIA COAST. OTHERWISE...SURFACE HIGH PRESSURE WILL BE
THE MAIN FEATURE. THE H850 MEAN TEMPERATURES ARE EXPECTED TO HOVER
INTO THE MIDDLE SINGLE DIGITS WHICH WILL RESULT IN MAINLY 60S FOR
VALLEY LOCATIONS AND OVERNIGHT LOWS INTO THE 40S.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
SCATTERED TO BROKEN LINE OF SHOWERS WILL MOVE ACROSS THE REGION THIS
MORNING. CIGS UPSTREAM WERE MAINLY MVFR WITH AN OCCASIONAL HIGH
END IFR. WILL MENTION PREDOMINANT MVFR CONDITIONS...ALTHOUGH BRIEF
IFR WILL CIGS WILL BE POSSIBLE THIS MORNING. WINDS TOO HAVE BEEN
A BIT GUSTY FROM THE SOUTHERLY DIRECTION AND HAVE INCREASED
MAGNITUDES IN THIS SET OF TAFS. VIS HAS NOT SHOWN MUCH
RESTRICTIONS AND WE WILL KEEP THE VALUES INTO VFR.
FRONTAL PASSAGE WILL SIGNIFY AN END TO THE SHOWERS AND A WIND SHIFT
TO THE WEST-NORTHWEST BY AFTERNOON. MAGNITUDES WILL REMAIN AROUND
10 KTS WITH AN OCCASIONAL GUST TO NEAR 20 KTS. CIGS WILL BE A
CHALLENGE AS IT WILL BE BORDERLINE BETWEEN MVFR/VFR...ESPECIALLY
FOR THE UPSLOPE CONDITIONS INTO KPSF.
OUTLOOK...
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
SUNDAY TO MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
MONDAY NIGHT TO TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
&&
.FIRE WEATHER...
A COLD FRONT WILL CROSS THE REGION THIS AFTERNOON...BRINGING SOME
SHOWERS AND PERHAPS A THUNDERSTORM...MAINLY SOUTH OF ALBANY.
RAINFALL AMOUNTS WITH SHOWERS LOOK TO BE UP TO HALF AN INCH IN OUR
NORTHWESTERN ZONES...AROUND A QUARTER INCH LOCALLY IN THE CAPITAL
REGION...LESS THAN THAT FURTHER SOUTH.
A SOUTH WIND WILL AVERAGE 10 TO 20 MPH TODAY...SHIFTING TO THE
NORTHWEST BEHIND THE COLD FRONT.
RH LEVELS WILL REMAIN ELEVATED THIS AFTERNOON...ONLY DROPPING INTO
THE 60S.
TONIGHT ALL THE SHOWERS WILL MOVE EAST FOLLOWED BY PARTIAL CLEARING.
A NORTHWEST BREEZE MIGHT BE ENOUGH TO MITIGATE THE FORMATION OF MOST
FOG.
FRIDAY WILL BE A DRY DAY WITH TEMPERATURES A BIT BELOW NORMAL. RH
VALUES BY AFTERNOON WILL BE IN THE 35-45 PERCENT RANGE. THE SURFACE
WIND WILL BE NORTH TO NORTHWEST 5-15 MPH.
THE NEXT CHANCE OF SHOWERS WILL BE ON SATURDAY.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE EXPECTED THE NEXT FIVE DAYS
ENDING MONDAY.
SHOWERS AND ANY THUNDERSTORMS TODAY WILL PRODUCE ONLY ABOUT HALF AN
INCH OF AVERAGE BASIN RAINFALL IN OUR NORTHERN AREAS...ABOUT A
QUARTER INCH OR LESS ALBANY SOUTHWARD.
THIS RAIN WILL NOT INFLUENCE ANY OF OUR MAIN STEM RIVERS THROUGH OUT
THE REGION.
ANY THUNDERSTORM COULD CONTAIN LOCALLY HEAVY RAINFALL...WITH AMOUNTS
CLOSER TO AN INCH...JUST ENOUGH TO PRODUCE SOME PONDING OF WATER IN
A FEW SPOTS.
DRY WEATHER WILL RETURN TONIGHT AFTER A POSSIBLE LEFTOVER EVENING
SHOWERS. IT WILL BE DRY FRIDAY...BUT THERE IS A CHANCE OF SHOWERS ON
SATURDAY WITH ANOTHER DISTURBANCE. THEN...DRY WEATHER RETURNS SUNDAY
INTO EARLY NEXT WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...BGM
AVIATION...BGM/JPV
FIRE WEATHER...HWJIV/WASULA
HYDROLOGY...HWJIV/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
635 AM EDT THU SEP 11 2014
.SYNOPSIS...
LOW PRESSURE IN EASTERN CANADA WILL DRIVE A COLD FRONT ACROSS THE
REGION THIS AFTERNOON. AHEAD OF THIS FRONT WILL BE SCATTERED SHOWERS
AND PERHAPS A THUNDERSTORM...MAINLY SOUTH OF ALBANY. BEHIND THIS
FRONT WILL COME THE COOLEST AIR MASS SINCE LATE MAY BY FRIDAY. A
DISTURBANCE MIGHT BRING A ROUND OF SHOWERS ON SATURDAY FOLLOWED BY
MORE COOL DRY WEATHER SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 630 AM EDT...SCATTERED MAINLY LIGHT SHOWERS WERE WORKING INTO
MUCH OF THE AREA. THIS BATCH WILL LEAVE BUT OTHERS WILL THROUGHOUT
THE DAY. LOW PRESSURE WAS WORKING THROUGH SOUTHERN ONTARIO DRAGGING
AA COLD FRONT INTO WESTERN NEW YORK.
FOR THIS UPDATE...JUST INCREASED HOURLY POPS A BIT THIS MORNING (DUE
TO THE SCATTERED SHOWERS MOVING QUICKLY EAST). OTHERWISE VERY LITTLE
TO TWEAK OTHER THAN THAT.
THE LATEST RUC13 INDICATED LITTLE OR NO INSTABILITY SO WE KEPT ANY
MENTION OF THUNDER OUT OF THE FORECAST THROUGH EARLY MORNING.
TEMPERATURES WERE QUITE MILD DUE TO AN INCREASE IN CLOUDS...AND A
PERSISTENT SOUTHERLY BREEZE ON THE WARM SIDE OF THE LOW
PRESSURE...HOLDING MAINLY IN THE 60S.
THE AFOREMENTIONED COLD FRONT ASSOCIATED WITH THE LOW PRESSURE WILL
MOVE STEADILY ALONG AND WORK INTO THE SOUTHERN ADIRONDACKS AND THE
MOHAWK VALLEY EARLY THIS AFTERNOON...THE CAPITAL REGION AND
SURROUNDING AREAS LATE AFTERNOON...AND THE MID HUDSON VALLEY AND
NORTHWESTERN CONNECTICUT BY EARLY EVENING.
DUE TO VERY LIMITED INSTABILITY WE ONLY MENTION A SLIGHT CHANCE OF
THUNDERSTORM FROM THE CAPITAL REGION NORTHWARD. FURTHER SOUTH...WITH
A LITTLE MORE INSTABILITY...WE DID MENTION A CHANCE OF
THUNDERSTORMS. IT IS REMOTELY POSSIBLE THAT ANY THUNDERSTORM IN THIS
AREA COULD CONTAIN SOME GUSTY WINDS AS THE OVERALL WIND FIELD (BULK
SHEAR) INCREASES TO ABOUT 35-40KTS. HOWEVER...THE THREAT APPEARED
LOW ENOUGH NOT TO MENTION IN THE GRIDS OR CERTAINLY ENHANCED WORDING
AT THIS TIME.
PWAT VALUES LOOK TO INCREASE TO ABOUT 2 INCHES...BUT THIS LOOKS TO
HAPPEN THIS MORNING. THE H20 WATER VAPOR LOOP ALREADY INDICATED A
MID LEVEL DRY PUNCH QUICKLY WORKING INTO WESTERN NEW YORK STATE.
THIS DRY PUNCH WILL ALLOW PWATS TO DROP QUICKLY THIS
AFTERNOON...EVEN AHEAD OF THE FRONT. THEREFORE THE BEST FORCING
(WHICH IS GOING TO WELL NORTH)...WILL NOT LINE UP WITH THE BEST
PWATS AND PASSAGE OF THE COLD FRONT.
THERE WILL BE PLENTY OF CLOUDS TODAY WITH PERHAPS A FEW BREAKS OF
AFTERNOON SUNSHINE. EVEN SO...TEMPERATURES COULD SPIKE A LITTLE
AHEAD OF THE FRONT. WE EXPECT HIGHS NEAR 80 IN THE MID HUDSON VALLEY
AND LOWER LITCHFIELD COUNTY...UPPER 70S AROUND ALBANY. FURTHER NORTH
AND WEST WHERE THE COLD FRONT WILL BE FIRST TO COME THROUGH...HIGH
TEMPERATURES WILL BE HELD TO BETWEEN THE UPPER 60S TO MID 70S.
A GUSTY SOUTH WIND PREVAIL TODAY 10 TO 20 MPH...SHIFTING TO THE WEST
BY LATE IN THE DAY ONCE THE COLD FRONT MOVES THROUGH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
THE COLD FRONT WILL BE FINISHING ITS SWEEP THROUGH OUR AREA THIS
EVENING TAKING ANY LEFTOVER SHOWERS WITH IT.
THEN...A COOL CANADIAN AIR MASS WILL BE USHERED IN TONIGHT ON
SOMEWHAT GUSTY NORTH OR NORTHWEST WINDS. THE SKY WILL CLEAR AND
TEMPERATURES WILL DIP DOWN TO AROUND 50 FROM ALBANY SOUTH AND EAST.
FURTHER NORTHWEST AND WEST...THEY WILL DIVE INTO THE 40S...AND EVEN
TOUCH THE UPPER 30S ACROSS OUR ADIRONDACKS.
FRIDAY LOOKS TO FEATURE A GOOD DEAL OF SUNSHINE (MIXING WITH FAIR
WEATHER STRATO-CUMULUS) AND TEMPERATURES BELOW NORMAL. H850
TEMPERATURES LOOK TO DROP TO BETWEEN +5C NORTHWEST TO +9C SOUTHEAST
ACROSS OUR REGION. THIS WILL TRANSLATE TO HIGH TEMPERATURES MAINLY
IN THE 60S THROUGH OUR REGION...PERHAPS TOUCHING 70 FROM
POUGHKEEPSIE...BUT ONLY 50S ACROSS THE ELEVATED TERRAIN NORTH OF
ALBANY...MAKING IT FEEL AUTUMNAL.
HIGH PRESSURE WILL CREST NORTH OF THE REGION EARLY FRIDAY NIGHT
BEFORE RETREATING TO THE CANADIAN MARITIMES. A COOL NIGHT IS IN
STORE BUT NOT AS COOL AS WOULD HAVE BEEN. WHILE THE NIGHT WILL START
CLEAR...CLOUDS SHOULD INCREASE DUE TO WARM AIR ADVECTION AS A POTENT
DISTURBANCE APPROACHES FROM THE OHIO VALLEY. OVERNIGHT LOWS WILL
RANGE FROM THE UPPER 40S SOUTHEAST OF ALBANY...DOWN TO THE UPPER 30S
ACROSS THE ADIRONDACKS. IF IT WERE TO GET ANY COLDER THERE...SOME
FROST WOULD BE POSSIBLE. WE WILL MONITOR THAT POTENTIAL BUT FOR
NOW...WE ARE FORECASTING TEMPERATURES TO REMAIN JUST ABOVE THE FROST
THRESHOLD.
THEN ON SATURDAY...AS THE AFOREMENTIONED DISTURBANCE APPROACH...IT
LOOKS AS OF SURFACE LOW PRESSURE WILL FORM AT THE TRIPLE POINT OF
THE WARM FRONT/COLD FRONT INTERFACE TO OUR SOUTHEAST. AT THIS POINT
SHOWERS APPEARS TO BE A GOOD BET. IF SURFACE LOW PRESSURE DEVELOPS
EVEN QUICKER...WE WOULD BE LOOKING AT A STEADY RAIN. FOR NOW...WILL
CALL IT SHOWERS...BUT EITHER WAY...SATURDAY LOOKS LIKE A
CLOUDY...DAMP DAY WITH HIGHS RANGING ONLY FROM THE MID 50S NORTHWEST
TO UPPER 60S SOUTHEAST OF ALBANY.
THE DISTURBANCE LOOKS TO MOVE QUICKLY EAST SATURDAY NIGHT...FOLLOWED
BY PARTIAL CLEAR AND ANOTHER CANADIAN HIGH PRESSURE BRINGING A
RE-NEWED SHOT OF COOL BUT DRY TO CLOSE OUT THE WEEKEND.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
THE LONG TERM PORTION OF THE FORECAST WILL FEATURE A BROAD UPPER
TROUGH ACROSS THE EASTERN 2/3RDS OF NOAM. THIS WILL KEEP
TEMPERATURES A BIT BELOW NORMAL ALONG WITH NEAR TO BELOW NORMAL
PRECIPITATION. THE NEXT APPRECIABLE CHANCE FOR WET WEATHER IS LATE
MONDAY NIGHT INTO TUESDAY AS THE NEXT PV ANOMALY IS PROGGED TO TRACK
ACROSS THE GREAT LAKES REGION AND NORTHEAST CONUS. QPF/S FROM THE
GLOBAL MODELS DIFFER AS THE GFS IS THE MOST AGGRESSIVE /LESS QPF/
WITH TRACK OF THIS WAVE. MEANWHILE THE ECMWF CONTINUES TO SUGGEST A
COASTAL WAVE DEVELOPMENT WHICH SLOWS DOWN THE FORWARD PROGRESS AND
KEEPS THE PRECIP LINGER LONGER /AND HIGHER QPF/. THE GGEM IS
FURTHER SOUTH WITH LIGHTER AMOUNTS AS MAIN WAVE MOVES OFF THE
CAROLINA/VIRGINIA COAST. OTHERWISE...SURFACE HIGH PRESSURE WILL BE
THE MAIN FEATURE. THE H850 MEAN TEMPERATURES ARE EXPECTED TO HOVER
INTO THE MIDDLE SINGLE DIGITS WHICH WILL RESULT IN MAINLY 60S FOR
VALLEY LOCATIONS AND OVERNIGHT LOWS INTO THE 40S.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
CLOUDS CONTINUE TO INCREASE...THICKEN AND LOWER ACROSS THE REGION
WITH LATEST VIEW OF THE 11U-3.9U SATELLITE IMAGERY REVEALING THE
EXPANDING LOW LEVEL STRATUS /MVFR CIGS/ FROM THE WEST-SOUTHWEST
DIRECTION ADVECTING NORTHWARD. WE WILL THEREFORE PLACE AT LEAST
MVFR FLIGHT RESTRICTIONS INTO THE TAF/S OVERNIGHT. AS FOR SHOWER
POTENTIAL...UPSTREAM REGIONAL RADAR MOSAIC SHOWS THE LEADING EDGE OF
THE PRECIP IS ERODING DUE TO THE DOWNSTREAM DRY AIRMASS IN PLACE.
PER THE LATEST HRRR REFLECTIVITY...EXPECTATIONS ARE FOR THE SHOWER
POTENTIAL TO INCREASE TOWARD SUNRISE AS THESE THOUGHTS ARE REFLECTED
IN THE TAF/S.
THE BEST TIME PERIOD FOR WET WEATHER APPEARS TO BE AROUND SUNRISE
AND INTO THE MID MORNING HOURS ASSOCIATED WITH THE FRONTAL PASSAGE.
AFTER FROPA...WINDS WILL SHIFT TOWARD THE WEST-NORTHWEST WITH A
DRIER MID LEVELS. HOWEVER...LOWER LEVEL MOISTURE MAY LINGER AS WE
WILL KEEP CIGS ON THE BORDER OF MVFR/VFR.
WINDS WILL BE SOUTHERLY TO SOUTHEASTERLY AROUND 3-7
KT...BECOMING SOUTH AND INCREASING TO 5-10 KT BY 12Z THURSDAY. WINDS
WILL SHIFT TO THE WEST-NORTHWEST AROUND 10KTS WITH SOME HIGHER GUSTS
TOWARD 20KTS POSSIBLE BY AFTERNOON.
OUTLOOK...
THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
SUNDAY TO MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
A COLD FRONT WILL CROSS THE REGION THIS AFTERNOON...BRINGING SOME
SHOWERS AND PERHAPS A THUNDERSTORM...MAINLY SOUTH OF ALBANY.
RAINFALL AMOUNTS WITH SHOWERS LOOK TO BE UP TO HALF AN INCH IN OUR
NORTHWESTERN ZONES...AROUND A QUARTER INCH LOCALLY IN THE CAPITAL
REGION...LESS THAN THAT FURTHER SOUTH.
A SOUTH WIND WILL AVERAGE 10 TO 20 MPH TODAY...SHIFTING TO THE
NORTHWEST BEHIND THE COLD FRONT.
RH LEVELS WILL REMAIN ELEVATED THIS AFTERNOON...ONLY DROPPING INTO
THE 60S.
TONIGHT ALL THE SHOWERS WILL MOVE EAST FOLLOWED BY PARTIAL CLEARING.
A NORTHWEST BREEZE MIGHT BE ENOUGH TO MITIGATE THE FORMATION OF MOST
FOG.
FRIDAY WILL BE A DRY DAY WITH TEMPERATURES A BIT BELOW NORMAL. RH
VALUES BY AFTERNOON WILL BE IN THE 35-45 PERCENT RANGE. THE SURFACE
WIND WILL BE NORTH TO NORTHWEST 5-15 MPH.
THE NEXT CHANCE OF SHOWERS WILL BE ON SATURDAY.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE EXPECTED THE NEXT FIVE DAYS
ENDING MONDAY.
SHOWERS AND ANY THUNDERSTORMS TODAY WILL PRODUCE ONLY ABOUT HALF AN
INCH OF AVERAGE BASIN RAINFALL IN OUR NORTHERN AREAS...ABOUT A
QUARTER INCH OR LESS ALBANY SOUTHWARD.
THIS RAIN WILL NOT INFLUENCE ANY OF OUR MAIN STEM RIVERS THROUGH OUT
THE REGION.
ANY THUNDERSTORM COULD CONTAIN LOCALLY HEAVY RAINFALL...WITH AMOUNTS
CLOSER TO AN INCH...JUST ENOUGH TO PRODUCE SOME PONDING OF WATER IN
A FEW SPOTS.
DRY WEATHER WILL RETURN TONIGHT AFTER A POSSIBLE LEFTOVER EVENING
SHOWERS. IT WILL BE DRY FRIDAY...BUT THERE IS A CHANCE OF SHOWERS ON
SATURDAY WITH ANOTHER DISTURBANCE. THEN...DRY WEATHER RETURNS SUNDAY
INTO EARLY NEXT WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...BGM
AVIATION...BGM
FIRE WEATHER...HWJIV/WASULA
HYDROLOGY...HWJIV/WASULA
AREA FORECAST DISCUSSION
NWS MIAMI FL
1049 AM EDT THU SEP 11 2014
.UPDATE...
ONLY SIGNIFICANT CHANGE TO THE FORECAST IS TO REDUCE POPS THIS
MORNING AS THERE HAS BEEN SOME WEAK SUBSIDENCE AHEAD OF THE WEAK
LOW OVER THE BAHAMAS. THE HRRR IS SHOWING THAT MOST CONVECTIVE
DEVELOPMENT OVER THE MAINLAND WILL HOLD OFF UNTIL AFTER 18Z. EVEN
THEN, MOST OF IT IS INDICATED TO BE OVER THE INTERIOR THIS
AFTERNOON. THE MODEL DOES THEN BRING SHOWERS AND THUNDERSTORMS TO
THE EASTERN COASTAL AREAS OF SOUTH FLORIDA THIS EVENING. THE ONLY
THREAT OF CONCERN RIGHT NOW IS A LOW CHANCE OF URBAN FLOODING DUE
TO SLOW MOVING HEAVY SHOWERS AND THUNDERSTORMS.
&&
.PREV DISCUSSION... /ISSUED 850 AM EDT THU SEP 11 2014/
AVIATION...
SHOWERS ARE LIKELY ALONG WITH A FEW THUNDERSTORMS ACROSS MUCH OF
THE AREA TODAY AS AN AREA OF LOW PRESSURE ACROSS THE BAHAMAS
PUSHES TO THE WEST. AS A RESULT...KEPT VCSH TRANSITIONING TO VCTS
AND THEN BACK TO VCSH AFTER 02Z AT ALL EAST COAST SITES THROUGH
THE PERIOD. WINDS WILL AGAIN BE GENERALLY EASTERLY AT ALL EAST
COAST SITES WITH A GULF BREEZE AT KAPF.
PREV DISCUSSION... /ISSUED 450 AM EDT THU SEP 11 2014/
DISCUSSION...
AN AREA OF LOW PRESSURE NEAR THE NORTHWEST BAHAMAS WILL DOMINATE
THE WEATHER DISCUSSION OVER THE NEXT COUPLE DAYS. MODELS ARE IN
GOOD AGREEMENT THAT THIS WEAK SYSTEM WILL MOVE SLOWLY WESTWARD
ACROSS THE NORTHWEST BAHAMAS AND THEN ACROSS SOUTH FLORIDA ON
FRIDAY. CONDITIONS ARE FORECAST TO BECOME UNFAVORABLE OVER THE LOW
TODAY AS SHEAR INCREASES. HOWEVER...THERE IS STILL A SLIGHT CHANCE
THAT THE SYSTEM MAY DEVELOP BEFORE MOVING INTO SOUTH FLORIDA...AND
THEN A MEDIUM CHANCE AFTER IT MOVES INTO THE GULF OF MEXICO OVER
THE WEEKEND. REGARDLESS OF DEVELOPMENT...THE MAIN IMPACT FOR
SOUTH FLORIDA WILL LIKELY BE LOCALLY HEAVY RAINFALL.
TODAY...THE WIND FIELD OVER/NEAR THE LOW IS LIGHT...AND WINDS ARE
FORECAST TO BE VERY LIGHT ACROSS THE REGION TODAY. A LIGHT
NORTHEASTERLY FLOW MAY BRIEFLY DEVELOP BEFORE SEA BREEZE
BOUNDARIES BECOME DOMINANT. STORM MOTION IS FORECAST TO BE
RELATIVELY SLOW TODAY...AND LOCALLY HEAVY RAINFALL IS POSSIBLE.
PONDING IN POORLY DRAINED AREAS AND LOCALIZED STREET FLOODING ARE
THE MAIN THREATS. RAIN CHANCES ARE 50-70% ACROSS THE
REGION. THE LATEST HRRR RUN SHOWS PRETTY HIGH COVERAGE OF RAIN
ACROSS THE REGION. HIGHS ARE FORECAST TO BE IN THE UPPER 80S TO
AROUND 90 DEGREES.
TONIGHT...THE WEAK AREA OF LOW PRESSURE WILL MOVE CLOSER TO THE
EAST COAST...IN THE VICINITY OF PALM BEACH COUNTY COAST BY
DAYBREAK. SCATTERED SHOWERS AND A FEW EMBEDDED STORMS ARE
FORECAST FOR THE EAST COAST METRO AREAS OVERNIGHT.
FRIDAY...THE AREA OF LOW PRESSURE IS FORECAST TO MOVE SLOWLY
ACROSS THE REGION...AND SHOWERS AND STORMS ARE LIKELY THROUGHOUT
THE DAY. LOCALLY HEAVY RAIN AND MINOR STREET FLOODING IS POSSIBLE.
CLOUD COVER AND RAINFALL IS FORECAST TO KEEP TEMPS IN THE 80S. THE
AREA OF LOW PRESSURE IS FORECAST TO MOVE SOUTHWEST INTO THE GULF
OF MEXICO FRIDAY NIGHT...AND RAIN CHANCES WILL CONTINUE ACROSS
COASTAL AREAS.
SATURDAY AND SUNDAY...DEEP MOISTURE WILL REMAIN ACROSS SOUTH
FLORIDA THROUGH THE WEEKEND. THE ECMWF KEEPS A TROUGH AXIS
LINGERING OVER THE REGION EXTENDING TO THE EAST OF THE AREA OF LOW
PRESSURE THROUGH SUNDAY. THE GFS MOVES THE SYSTEM QUICKLY
WESTWARD ACROSS THE GULF...WITH A RETURN OF THE DEEP EAST TO
SOUTHEAST FLOW OBSERVED OVER THE PAST SEVERAL DAYS ON SUNDAY AS
THE RIDGE BUILDS WESTWARD ACROSS THE REGION. SO RAIN CHANCES WILL
REMAIN IN THE LIKELY CATEGORY ON SATURDAY...AND THEN COME DOWN A
LITTLE ON SUNDAY.
HIGH PRESSURE WILL THEN BUILD ACROSS THE REGION EARLY NEXT
WEEK...WITH A MORE TYPICAL EASTERLY FLOW RAINY SEASON PATTERN.
MARINE...
A WEAK AREA OF LOW PRESSURE NEAR THE NORTHERN BAHAMAS IS FORECAST
TO PUSH SLOWLY WEST ACROSS THE LOCAL ATLANTIC WATERS TONIGHT AND
THEN INTO THE GULF WATERS FRIDAY NIGHT. THE NHC IS MONITORING
THIS DISTURBANCE...AND THIS COULD IMPACT THE FORECAST FOR FRIDAY
AND INTO THE WEEKEND. LIGHT WINDS ARE FORECAST TODAY...WITH
GENERALLY EAST TO SOUTHEAST WINDS FRIDAY THROUGH THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 88 75 86 76 / 60 40 60 20
FORT LAUDERDALE 89 76 88 77 / 60 40 60 30
MIAMI 88 75 86 77 / 60 30 70 30
NAPLES 90 74 89 75 / 60 30 60 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...13/SI
LONG TERM....84/AK
AREA FORECAST DISCUSSION
NWS MIAMI FL
850 AM EDT THU SEP 11 2014
.AVIATION...
SHOWERS ARE LIKELY ALONG WITH A FEW THUNDERSTORMS ACROSS MUCH OF
THE AREA TODAY AS AN AREA OF LOW PRESSURE ACROSS THE BAHAMAS
PUSHES TO THE WEST. AS A RESULT...KEPT VCSH TRANSITIONING TO VCTS
AND THEN BACK TO VCSH AFTER 02Z AT ALL EAST COAST SITES THROUGH
THE PERIOD. WINDS WILL AGAIN BE GENERALLY EASTERLY AT ALL EAST
COAST SITES WITH A GULF BREEZE AT KAPF.
&&
.PREV DISCUSSION... /ISSUED 450 AM EDT THU SEP 11 2014/
DISCUSSION...
AN AREA OF LOW PRESSURE NEAR THE NORTHWEST BAHAMAS WILL DOMINATE
THE WEATHER DISCUSSION OVER THE NEXT COUPLE DAYS. MODELS ARE IN
GOOD AGREEMENT THAT THIS WEAK SYSTEM WILL MOVE SLOWLY WESTWARD
ACROSS THE NORTHWEST BAHAMAS AND THEN ACROSS SOUTH FLORIDA ON
FRIDAY. CONDITIONS ARE FORECAST TO BECOME UNFAVORABLE OVER THE LOW
TODAY AS SHEAR INCREASES. HOWEVER...THERE IS STILL A SLIGHT CHANCE
THAT THE SYSTEM MAY DEVELOP BEFORE MOVING INTO SOUTH FLORIDA...AND
THEN A MEDIUM CHANCE AFTER IT MOVES INTO THE GULF OF MEXICO OVER
THE WEEKEND. REGARDLESS OF DEVELOPMENT...THE MAIN IMPACT FOR
SOUTH FLORIDA WILL LIKELY BE LOCALLY HEAVY RAINFALL.
TODAY...THE WIND FIELD OVER/NEAR THE LOW IS LIGHT...AND WINDS ARE
FORECAST TO BE VERY LIGHT ACROSS THE REGION TODAY. A LIGHT
NORTHEASTERLY FLOW MAY BRIEFLY DEVELOP BEFORE SEA BREEZE
BOUNDARIES BECOME DOMINANT. STORM MOTION IS FORECAST TO BE
RELATIVELY SLOW TODAY...AND LOCALLY HEAVY RAINFALL IS POSSIBLE.
PONDING IN POORLY DRAINED AREAS AND LOCALIZED STREET FLOODING ARE
THE MAIN THREATS. RAIN CHANCES ARE 50-70% ACROSS THE
REGION. THE LATEST HRRR RUN SHOWS PRETTY HIGH COVERAGE OF RAIN
ACROSS THE REGION. HIGHS ARE FORECAST TO BE IN THE UPPER 80S TO
AROUND 90 DEGREES.
TONIGHT...THE WEAK AREA OF LOW PRESSURE WILL MOVE CLOSER TO THE
EAST COAST...IN THE VICINITY OF PALM BEACH COUNTY COAST BY
DAYBREAK. SCATTERED SHOWERS AND A FEW EMBEDDED STORMS ARE
FORECAST FOR THE EAST COAST METRO AREAS OVERNIGHT.
FRIDAY...THE AREA OF LOW PRESSURE IS FORECAST TO MOVE SLOWLY
ACROSS THE REGION...AND SHOWERS AND STORMS ARE LIKELY THROUGHOUT
THE DAY. LOCALLY HEAVY RAIN AND MINOR STREET FLOODING IS POSSIBLE.
CLOUD COVER AND RAINFALL IS FORECAST TO KEEP TEMPS IN THE 80S. THE
AREA OF LOW PRESSURE IS FORECAST TO MOVE SOUTHWEST INTO THE GULF
OF MEXICO FRIDAY NIGHT...AND RAIN CHANCES WILL CONTINUE ACROSS
COASTAL AREAS.
SATURDAY AND SUNDAY...DEEP MOISTURE WILL REMAIN ACROSS SOUTH
FLORIDA THROUGH THE WEEKEND. THE ECMWF KEEPS A TROUGH AXIS
LINGERING OVER THE REGION EXTENDING TO THE EAST OF THE AREA OF LOW
PRESSURE THROUGH SUNDAY. THE GFS MOVES THE SYSTEM QUICKLY
WESTWARD ACROSS THE GULF...WITH A RETURN OF THE DEEP EAST TO
SOUTHEAST FLOW OBSERVED OVER THE PAST SEVERAL DAYS ON SUNDAY AS
THE RIDGE BUILDS WESTWARD ACROSS THE REGION. SO RAIN CHANCES WILL
REMAIN IN THE LIKELY CATEGORY ON SATURDAY...AND THEN COME DOWN A
LITTLE ON SUNDAY.
HIGH PRESSURE WILL THEN BUILD ACROSS THE REGION EARLY NEXT
WEEK...WITH A MORE TYPICAL EASTERLY FLOW RAINY SEASON PATTERN.
MARINE...
A WEAK AREA OF LOW PRESSURE NEAR THE NORTHERN BAHAMAS IS FORECAST
TO PUSH SLOWLY WEST ACROSS THE LOCAL ATLANTIC WATERS TONIGHT AND
THEN INTO THE GULF WATERS FRIDAY NIGHT. THE NHC IS MONITORING
THIS DISTURBANCE...AND THIS COULD IMPACT THE FORECAST FOR FRIDAY
AND INTO THE WEEKEND. LIGHT WINDS ARE FORECAST TODAY...WITH
GENERALLY EAST TO SOUTHEAST WINDS FRIDAY THROUGH THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 88 75 86 76 / 60 40 60 20
FORT LAUDERDALE 89 76 88 77 / 60 40 60 30
MIAMI 88 75 86 77 / 60 30 70 30
NAPLES 90 74 89 75 / 50 30 60 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
1122 AM EDT THU SEP 11 2014
.UPDATE...
ALREADY SHOWERS ACROSS FAR NORTH GEORGIA. BOTH HRRR AND LOCAL WRF
INCREASE DEVELOPMENT INTO THE AFTERNOON HOWEVER TWO OTHER HI RES
MODELS ARE MUCH MORE CONSERVATIVE IN TERMS OF PRECIPITATION.
CONSIDERING THE TRENDS OF THE HRRR THIS SUMMER...IT MAY BE
SLIGHTLY OVERDONE. UPDATED POPS THIS MORNING LEAN TOWARDS THE
BETTER CHANCES OF PRECIPITATION...GIVEN APPROACHING FRONTAL
BOUNDARY...BUT DO NOT SHOW BETTER PRECIP CHANCES AS FAR SOUTH AS
THE HRRR AND THE LOCAL WRF. WILL HAVE TO CONTINUE TO MONITOR THE
PRECIP TRENDS THOUGH FOR FUTURE UPDATES.
11
&&
.PREV DISCUSSION...
SHORT TERM /TODAY THROUGH FRIDAY/...
/ISSUED AT 456 AM EDT THU SEP 11 2014/
MODELS IN CLOSE AGREEMENT THROUGH THE LONG TERM. SURFACE FRONT AND
ASSOCIATED SHORT WAVE WILL MOVE INTO THE TENNESSEE VALLEY TODAY AND
THIS WILL INCREASE THE RISK OF SHOWERS AND TSTORMS OVER NORTH GA
THIS AFTERNOON. ALTHOUGH SHEAR IS NOT IMPRESSIVE...SBCAPES ARE
RUNNING IN THE 1500 TO 2500 DEPENDING ON THE MODEL WHICH COULD
BE ENOUGH TO PRODUCE STRONG STORMS WITH GUSTY WINDS. THE
INHIBITING FACTOR TO STRONG STORMS WILL BE THE H5 HIGH SITTING
OVER THE GA/AL BORDER NEAR CSG. PROXIMITY TO THIS COULD KEEP
TSTORMS FROM GOING SEVERE...HOWEVER THIS WILL NEED TO BE WATCHED. A
DIFFERENT STORY ON FRIDAY AS THE H5 HIGH WEAKENS AND THE SURFACE
FRONT DROPS INTO THE STATE. CONVERGENCE ALONG THE FRONT AS WELL AS
CAPES IN THE 2000 TO 2500 RANGE BY ALL MODELS WILL BE ENOUGH FOR A
FEW STRONG TO SEVERE STORMS TO DEVELOP DURING FRIDAY
AFTERNOON...MAINLY ACROSS NORTH GEORGIA.
17
LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
/ISSUED AT 456 AM EDT THU SEP 11 2014/
EXTENDED MODELS CONSISTENT WITH SHOWING AFOREMENTIONED SHORT-TERM
FRONT STALLED ACROSS THE STATE SATURDAY AS A SECONDARY FRONT
APPROACHES THE AREA. UPPER LOW TRACKING ACROSS THE SOUTHERN GREAT
LAKES WILL PULL THE SECOND FRONT INTO THE REGION QUICKLY BEHIND
THE FIRST...WITH AMPLE MOISTURE POSITIONED ACROSS THE STATE
SATURDAY THROUGH EARLY NEXT WEEK AS BOUNDARIES BECOME STATIONARY
AND PILE UP ACROSS CENTRAL GEORGIA. THESE FRONTS WILL SERVE AS A
FOCUS FOR ENHANCED SHOWERS AND THUNDERSTORMS ACROSS THE STATE. NOT
UNTIL A SHORTWAVE SWEEPS INTO THE REGION TUESDAY AND KICKS THE
STATIONARY FRONTS EASTWARD DOES THE STATE REALLY GET TO SEE SOME
DRIER AIR MOVE INTO THE STATE.
FOR NOW...HAVE OPTED TO CONTINUE WITH GOOD CHANCE TO LIKELY POPS
ACROSS A VAST MAJORITY OF THE AREA SATURDAY THROUGH MONDAY. INTO
MID WEEK NEXT WEEK THE EXTENDED MODELS DISAGREE WITH THE EXTENT
THE DRIER AIR PUSHES INTO THE STATE AND WITH A SERIES OF UPPER
LEVEL DISTURBANCES THROUGH THE AREA. AS A RESULT...ASIDE FROM ZERO
POPS IN FAR NW GEORGIA ON SUNDAY NIGHT AND TUESDAY NIGHT...CARRY
AT LEAST GOOD CHANCE POPS ACROSS THE STATE EACH AFTERNOON...AND
AT LEAST SLIGHT CHANCE EACH OVERNIGHT.
MODELS ARE INDICATING THAT COOLER TEMPERATURES ARE IN STORE FOR
THE STATE BY THE WEEKEND...ESPECIALLY WITH THE INFLUENCE OF THE
PRECIPITATION AND CLOUDS. ANTICIPATE AN OVERALL COOLING TREND
THROUGH THE WEEK...AND BY THE LATTER HALF OF NEXT WEEK COULD BE
BELOW NORMAL FOR TEMPERATURES.
AS OF NOW...WEEKEND QPF IS EXPECTED TO BE 0.75 TO 1.5
INCHES...WITH THE HIGHEST AMOUNTS GENERALLY NOSING INTO THE STATE
FROM THE CAROLINAS. LOCALLY HEAVIER AMOUNTS CAN BE EXPECTED. AT
THIS TIME...GUIDANCE SUGGESTS MUCH OF THE STATE CAN HANDLE THIS
AMOUNT OF RAINFALL AND WILL NOT ISSUE ANY KIND OF WATCH AT THIS TIME.
31
AVIATION...
12Z UPDATE...
/ISSUED 729 AM EDT THU SEP 11 2014/
NOT A CONTINUOUS CLOUD COVER ACROSS THE FORECAST AREA WITH POCKETS
OF IFR CLOUDS OVER CENTRAL GA AND POCKES OF 3000 TO 4000 FT CIGS
ACROSS THE REST OF THE FORECAST AREA. ALL AREAS SHOULD BE VFR WITH
INCREASING CLOUD COVER BY LATE THIS MORNING...AND REMAIN VFR FOR THE
REMAINDER OF THE FORECAST. DO EXPECT A MOSTLY BROKEN CLOUD COVER
ACROSS NORTH GA THROUGH THE FORECAST WHILE CENTRAL GA SHOULD BE
SCT-BKN. WINDS WILL BE WEST TO SOUTHWEST WITH SPEEDS OF 6 KTS OR
LESS TODAY...GOING NEAR CALM AFTER SUNSET THIS EVENING. ISOLATED
SHOWERS HAVE ALREADY DEVELOPED ACROSS NORTH GA AND WHILE THERE COULD
BE ISOLATED TSRA THIS AFTERNOON OVER THE FORECAST AREA...THE BEST
CHANCES WILL REMAIN NORTH OF THE TAF SITES.
//ATL CONFIDENCE...12Z UPDATE...
MEDIUM CONFIDENCE ON CIGS.
HIGH CONFIDENCE ON REMAINING ELEMENTS.
17
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 90 71 90 70 / 40 40 60 60
ATLANTA 88 72 89 72 / 40 40 50 50
BLAIRSVILLE 82 67 81 65 / 60 50 60 60
CARTERSVILLE 88 71 89 69 / 50 50 60 50
COLUMBUS 91 73 93 72 / 20 20 40 40
GAINESVILLE 85 71 87 69 / 50 50 60 60
MACON 92 71 93 71 / 20 20 40 40
ROME 89 70 89 69 / 50 50 60 50
PEACHTREE CITY 89 70 90 69 / 30 30 50 40
VIDALIA 92 72 93 72 / 20 20 40 40
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...11
LONG TERM....BAKER
AVIATION...11
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
607 AM CDT THU SEP 11 2014
...UPDATE FOR THE AVIATION DISCUSSION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 112 AM CDT THU SEP 11 2014
SHORT TERM MODELS INDICATE AN UPPER LEVEL SHORTWAVE TROUGH DIGGING
SOUTHEAST ACROSS THE NORTHERN ROCKIES TODAY AND PUSHING FURTHER
SOUTHEAST INTO THE WESTERN HIGH PLAINS TONIGHT SETTING UP PRECIP
CHANCES ACROSS NEBRASKA SOUTHWARD INTO PORTIONS OF WESTERN KANSAS.
AS THE SHORTWAVE APPROACHES THIS EVENING, A SERIES OF H5 VORT MAXIMA
WILL BEGIN TO EJECT EASTWARD OUT OF THE COLORADO ROCKIES INTO THE
HIGH PLAINS OF EASTERN COLORADO AND WESTERN KANSAS. MEANWHILE, AN
ATTENDANT COLD FRONT TO THE SHORTWAVE WILL BEGIN TO PUSH SOUTHWARD
ACROSS WESTERN KANSAS LATE THIS EVENING INTO EARLY FRIDAY MORNING.
OVERNIGHT, DYNAMIC SUPPORT ALOFT WILL BECOME MORE FAVORABLE AS THE
RIGHT FRONT ENTRANCE REGION TO A +90KT JET EXITING THE APPROACHING
TROUGH AXIS SHIFTS SOUTHWARD INTO WESTERN KANSAS. AS A RESULT, RAIN
CHANCES WILL INCREASE ACROSS WESTERN KANSAS THIS EVENING, SPREADING
SOUTH AND EAST ACROSS THE REGION OVERNIGHT. A FEW ISOLATED
THUNDERSTORMS WILL BE POSSIBLE ACROSS EXTREME SOUTHWEST KANSAS THIS
EVENING WHERE SOME INCREASED INSTABILITY AND MORE FAVORABLE VERTICAL
SHEAR PROFILES WILL EXIST IN A SOUTHEASTERLY UPSLOPE FLOW. HOWEVER,
NAM/GFS MODEL SOUNDINGS INDICATE LIMITED INSTABILITY WITH CAPE
VALUES REMAINING WELL UNDER 1000 J/KG. THIS WILL RESTRICT THE
POTENTIAL FOR SEVERE STORMS ACROSS SOUTHWEST KANSAS.
TEMPERATURES WILL BE WELL BELOW NORMAL TODAY AS COOLER AIR FILTERS
SOUTHWARD INTO WESTERN KANSAS AHEAD OF A BROAD SURFACE HIGH MOVING
SOUTHEASTWARD OUT OF THE NORTHERN ROCKIES INTO THE HIGH PLAINS OF
EASTERN WYOMING AND WESTERN NEBRASKA. THE NAM AND GFS SHOW H85
TEMPERATURES FALLING BELOW 10C ACROSS CENTRAL KANSAS NEAR THE I-70
CORRIDOR BY THIS AFTERNOON WITH THE MID TO UPPER TEENS(C) ACROSS
EXTREME SOUTHWEST KANSAS WITHIN A SOUTHEAST UPSLOPE FLOW.
ADDITIONALLY, HIGH TEMPERATURES MAY BE HINDERED TODAY DEPENDING ON
HOW FAR SOUTH LOW LEVEL STRATUS MOVING OUT OF NEBRASKA THIS
MORNING PUSHES INTO SOUTHWEST KANSAS, NOT TO MENTION HOW LONG IT
MAY LAST. THE HRRR SUGGESTS THE STRATUS DECK PERSISTING THROUGH AT
LEAST MID DAY, PARTICULARLY ACROSS CENTRAL KANSAS IN THE VICINITY
OF THE I-70 CORRIDOR. BECAUSE OF THIS, HIGHS MAY STRUGGLE TO REACH
THE 60S(F) IN CENTRAL KANSAS WITH THE LOWER TO MID 70S(F) POSSIBLE
CLOSER TO THE OKLAHOMA BORDER, ESPECIALLY IN EXTREME SOUTHWEST
KANSAS. A SECONDARY PUSH OF COLDER AIR BEHIND YET ANOTHER COLD
FRONT PUSHING ACROSS WESTERN KANSAS EARLY FRIDAY MORNING WILL
LIKELY DROP LOWS DOWN INTO THE 40S(F) ACROSS MUCH OF CENTRAL AND
SOUTHWEST KANSAS TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 318 AM CDT THU SEP 11 2014
FRIDAY WILL BE COOL AND MOIST, WITH LIGHT RAIN LIKELY.
FRIDAY WILL BE IN A POST FRONTAL REGIME, WITH COOL HIGH PRESSURE
BUILDING IN FROM THE NORTHWEST. THE SURFACE FLOW WILL BE UPSLOPE
WITH NORTHEAST TO EASTERLY WINDS AT 10 TO 20 MPH. CLOUDS WILL BE
THICKEST IN THE MORNING, BUT STILL PREVALENT IN THE AFTERNOON. MAX
TEMPS WILL GENERALLY BE IN THE 50S, BUT I ONLY EXPECT LIGHT RAIN
WITH 0.05 TO 0.10 INCH ACCUMULATION. THE HIGH PRESSURE WILL BEGIN
TO DOMINATE FRIDAY EVENING, LEADING TO CLEAR SKIES OVERNIGHT. THE
COOL AIR WILL FILTRATE IN FROM THE NORTHWEST, AND FROST MAY BE
POSSIBLE IN OUR EXTREME NORTHWESTERN COUNTIES OF TREGO, AND
NORTHERN LANE AND SCOTT COUNTIES SATURDAY MORNING. AS THAT TIME
FRAME APPROACHES, WE WILL NEED TO LOOK INTO A POSSIBLE WATCH OR
REFINE THE AREA WHERE FROST MAY OCCUR.
AFTER THE FALL-LIKE WEATHER ON FRIDAY, SATURDAY AND SUNDAY WILL
SHOW A GRADUAL WARM UP, WITH HIGHS REACHING THE MID 60S TO LOWER
70S ON SATURDAY, AND BOUNDING UPWARD TO THE UPPER 70S TO LOWER 80S
BY SUNDAY. A COLD FRONT WILL PLOW THROUGH TO THE SOUTHEAST ON
MONDAY AFTERNOON, BRINGING A CHANCE FOR THUNDERSTORMS TO OUR
SOUTHEAST-MOST ZONES, PRIMARILY IN PRATT AND BARBER COUNTIES. AN
UPPER LEVEL WAVE WILL COME THROUGH IN THE FLOW MONDAY NIGHT,
GIVING MOST OF THE CWA A 20 TO 30 PERCENT CHANCE FOR
THUNDERSTORMS. A LEE SIDE TROUGH WILL BE IN WESTERN KANSAS TUESDAY
AND WEDNESDAY, AND SLIGHT CHANCES FOR SHOWERS AND ISOLATED
THUNDERSTORMS WILL EXIST ACROSS MOST OF OUR FORECAST AREA, MAINLY
THE EAST.
WEDNESDAY WILL SEE A RETURN TO A WARM SOUTHWEST FLOW, AND HIGH
TEMPERATURES WILL RESPOND LIKEWISE WITH VALUES IN THE LOWER 80S
NORTH OF I-70 AND THE MIDDLE 80S SOUTHWEST A LINE FROM GARDEN CITY
TO DODGE CITY TO MEDICINE LODGE. WINDS THROUGH THE EXTENDED DO NOT
LOOK TOO STRONG, EXCEPT AHEAD OF THE FRONT ON MONDAY, AND THEN
AGAIN BEHIND THE FRONT ON TUESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 603 AM CDT THU SEP 11 2014
SETTLING HIGH PRESSURE HAS RESULTED IN LIGHT UPSLOPE, EAST-
NORTHEASTERLY WINDS AT THE SURFACE. STRATUS CLOUDS AND SOME FOG
FORMED IN THE MOIST, UPSLOPE FLOW. IFR CONDITIONS WILL PREVAIL
UNTIL ABOUT NOON, THEN MFVR CIGS WITH VFR VSBYS ARE EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 65 45 53 40 / 10 70 70 0
GCK 65 42 50 38 / 10 70 70 0
EHA 75 45 51 43 / 20 80 70 0
LBL 72 48 54 42 / 10 70 70 0
HYS 58 42 52 38 / 10 70 70 0
P28 65 50 58 43 / 10 70 70 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JJOHNSON
LONG TERM...BURKE
AVIATION...BURKE
AREA FORECAST DISCUSSION
NWS JACKSON KY
1014 AM EDT THU SEP 11 2014
.UPDATE...
ISSUED AT 1014 AM EDT THU SEP 11 2014
MADE ADJUSTMENTS TO TIMING OF SOUTHWARD PROGRESSION OF HIGHER POPS
TODAY...BUT WITH LITTLE IMPACT ON THE GENERAL 12 HOUR OUTLOOK.
UPDATE ISSUED AT 645 AM EDT THU SEP 11 2014
MADE A FEW ADJUSTMENTS TO THE FORECAST GRIDS FOR EARLY THIS MORNING
BASED ON THE CURRENT RADAR TRENDS. DECIDED TO SLIGHTLY SPEED UP THE
EASTWARD PROGRESSION OF SHOWERS AND STORMS THIS MORNING PER LATEST
RADAR. BASED ON UPSTREAM SHOWER AND STORM FORMATION...AND THE STILL
SLOW EASTWARD MOVEMENT OF THE COLD FRONT...IT STILL APPEARS THAT
WIDESPREAD RAINFALL WILL OCCUR ACROSS EASTERN KENTUCKY THROUGH THIS
AFTERNOON. LOCALLY HEAVY RAINFALL...AND PERHAPS SOME ISOLATED
INSTANCES OF FLOODING...WILL STILL BE POSSIBLE AS NUMEROUS STORMS
WILL LIKELY MOVE ACROSS THE SAME LOCATIONS THROUGHOUT THE DAY.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 323 AM EDT THU SEP 11 2014
THE MODELS WERE IN GOOD AGREEMENT WITH THE LARGE SCALE AND LOCAL
WEATHER PATTERN FOR THE FIRST 36 HOURS OF THE FORECAST. THE
NAM12...SREF...AND HRRR MODELS HAVE ALL HANDLED THE TIMING AND
EVOLUTION OF A LINE OF SHOWERS AND STORMS THAT IS CURRENTLY MOVING
ACROSS CENTRAL KENTUCKY AND SOUTHERN OHIO. THE NAM12 AND SREF SEEM TO
DO A BETTER JOB OF HANDLING THE EVOLUTION OF THIS LINE OF SHOWERS AND
STORMS AFTER SUNRISE TODAY THAN THE HRRR...SO THOSE TWO MODELS WERE
USED TO CREATE THE NEW FORECAST. THE MODELS SUGGEST A STRONG COLD
FRONT WILL MOVE ACROSS CENTRAL AND EASTERN KENTUCKY TODAY...WITH THE
BOUNDARY EXITING THE AREA LATE THIS AFTERNOON. WIDESPREAD SHOWERS AND
STORMS ARE EXPECTED TO CONTINUE FIRING ALONG AND JUST AHEAD OF THIS
FRONT...WITH THE PEAK IN ACTIVITY OCCURRING BETWEEN ROUGHLY NOON AND
5 PM. THE LATEST FORECAST SOUNDINGS CONTINUE TO SUPPORT THE POTENTIAL
FOR LOCALLY HEAVY RAINFALL...WITH PRECIPITABLE WATER VALUES OF AROUND
2 INCHES PERSISTING THROUGH THE OVERNIGHT HOURS. SOME OF THE STRONGER
THUNDERSTORMS COULD ALSO PRODUCE GUSTY WINDS...BUT LOCALLY HEAVY
RAINFALL WILL BE THE PRIMARY THREAT. THE RAIN CHANCES WILL NOT END
ONCE THE FRONT HAS PASSED BY US...HOWEVER. THE BOUNDARY IS EXPECTED
TO STALL ACROSS THE TENNESSEE VALLEY ON FRIDAY. WAVES OF LOW PRESSURE
ARE THEN PROGGED TO MIGRATE FROM WEST TO EAST ALONG THE FRONT. THESE
DISTURBANCES WILL BRING ENOUGH LIFT AND MOISTURE TO LOCATIONS SOUTH
OF THE MOUNTAIN PARKWAY TO PERHAPS FIRE OFF ISOLATED TO SCATTERED
RAIN SHOWERS LATE TONIGHT THROUGH THE END OF THE DAY ON FRIDAY.
ONCE THE FRONT MOVES THROUGH EARLY TONIGHT...AN UNSEASONABLY COOL
CANADIAN AIR MASS WILL SETTLE OVER THE AREA. THIS AIR MASS WILL BRING
FALL LIKE TEMPERATURES TO EASTERN KENTUCKY TONIGHT AND FRIDAY. THE
COOL WEATHER WILL FIRST BE EXPERIENCED LATE TONIGHT...AS WINDS SHIFT
TO THE NORTH AND THE COOL AIR FULLY INVADES THE REGION. TONIGHTS
LOWS ARE EXPECTED TO BOTTOM OUT IN THE LOW TO MID 60S FOR MOST
LOCATIONS. FOLKS ALONG AND NORTH OF THE I-64 CORRIDOR MAY SEE THE
MERCURY DIP INTO THE UPPER 50S BY FRIDAY MORNING. HIGH TEMPERATURES
ON FRIDAY WILL LIKELY ONLY CLIMB INTO THE LOW TO MID 70S ACROSS THE
AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 431 AM EDT THU SEP 11 2014
THE MODELS ARE IN GOOD AGREEMENT WITH THE LONG WAVE PATTERN THROUGH
THE PERIOD. PROGRESSIVE AND AMPLIFIED FLOW WILL CONTROL ACROSS THE
NORTHERN HALF OF THE CONUS AS SEVERAL PASSING SHORT WAVES HELP TO
REINFORCE TROUGHING ACROSS THE REGION. UPPER LEVEL RIDGING HANGING ON
ACROSS THE SOUTHERN CONUS WILL GRADUALLY DAMPEN AND GET SUPPRESSED
FURTHER SOUTH INTO EARLY NEXT WEEK...BEFORE CONSOLIDATING MORE ACROSS
THE DESERT SOUTHWEST BY THE MIDDLE OF NEXT WEEK.
FOR EASTERN KENTUCKY...THE FIRST MAIN SHORT WAVE WILL MOVE THROUGH
FRIDAY NIGHT INTO SATURDAY...BRINGING A CHANCE OF SHOWERS. GENERALLY
DRY WEATHER CAN BE EXPECTED FROM SATURDAY NIGHT THROUGH SUNDAY
NIGHT...AS HIGH PRESSURE TEMPORARILY BUILDS IN AT THE SURFACE. A
DEEPER TROUGH AXIS...WITH SOME SURFACE DEVELOPMENT NOTED BY THE
MODELS...WILL THEN AFFECT THE AREA FROM MONDAY THROUGH
TUESDAY. THIS SYSTEM WILL BRING SOME RENEWED CHANCES OF
SHOWERS...ALTHOUGH THERE WILL NOT BE AS MUCH LOW LEVEL MOISTURE TO
WORK WITH...SO STUCK FAIRLY CLOSE TO THE BLENDED GUIDANCE ON THE
POPS. DRY WEATHER WILL ENSUE ONCE AGAIN THEREAFTER...AS SURFACE HIGH
PRESSURE BUILDS IN ACROSS THE OHIO VALLEY.
TEMPERATURES WILL AVERAGE BELOW NORMAL THROUGH THE PERIOD...WITH
HIGHS MAINLY IN THE LOW TO MID 70S AND LOWS IN THE 50S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 645 AM EDT THU SEP 11 2014
WIDESPREAD SHOWERS AND STORMS WILL LOCALLY HEAVY RAINFALL AND GUSTY
WINDS ARE STILL ON TAP TODAY AT ALL FOUR TAF SITES. MVFR AND AT TIMES
IFR CONDITIONS WILL BE POSSIBLE DUE TO HEAVY RAINFALL AND FOG WITH
SHOWERS AND STORMS TODAY. THE RAIN IS EXPECTED TO LAST ALL DAY BEFORE
TAPERING OFF THIS EVENING. WINDS ARE EXPECTED TO SHIFT TO TO THE WEST
LATE THIS AFTERNOON AND THEN TO THE NORTH THIS EVENING AS THE FRONT
MOVES PAST. LOW LEVEL CLOUD COVER WILL LIKELY PLAGUE THE TAF SITES
THROUGH TOMORROW MORNING AS THE FRONT STALLS OUT TO OUR SOUTH AND
MOIST AIR CONTINUES TO RIDE UP AND OVER THE BOUNDARY. ISOLATED RAIN
SHOWERS WILL ALSO LINGER OVERNIGHT INTO EARLY TOMORROW...PARTICULARLY
NEAR LOZ AND SME...WHICH WILL BE CLOSER TO THE FRONT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...AR
LONG TERM...GEOGERIAN
AVIATION...AR
AREA FORECAST DISCUSSION
NWS JACKSON KY
645 AM EDT THU SEP 11 2014
.UPDATE...
ISSUED AT 645 AM EDT THU SEP 11 2014
MADE A FEW ADJUSTMENTS TO THE FORECAST GRIDS FOR EARLY THIS MORNING
BASED ON THE CURRENT RADAR TRENDS. DECIDED TO SLIGHTLY SPEED UP THE
EASTWARD PROGRESSION OF SHOWERS AND STORMS THIS MORNING PER LATEST
RADAR. BASED ON UPSTREAM SHOWER AND STORM FORMATION...AND THE STILL
SLOW EASTWARD MOVEMENT OF THE COLD FRONT...IT STILL APPEARS THAT
WIDESPREAD RAINFALL WILL OCCUR ACROSS EASTERN KENTUCKY THROUGH THIS
AFTERNOON. LOCALLY HEAVY RAINFALL...AND PERHAPS SOME ISOLATED
INSTANCES OF FLOODING...WILL STILL BE POSSIBLE AS NUMEROUS STORMS
WILL LIKELY MOVE ACROSS THE SAME LOCATIONS THROUGHOUT THE DAY.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 323 AM EDT THU SEP 11 2014
THE MODELS WERE IN GOOD AGREEMENT WITH THE LARGE SCALE AND LOCAL
WEATHER PATTERN FOR THE FIRST 36 HOURS OF THE FORECAST. THE
NAM12...SREF...AND HRRR MODELS HAVE ALL HANDLED THE TIMING AND
EVOLUTION OF A LINE OF SHOWERS AND STORMS THAT IS CURRENTLY MOVING
ACROSS CENTRAL KENTUCKY AND SOUTHERN OHIO. THE NAM12 AND SREF SEEM TO
DO A BETTER JOB OF HANDLING THE EVOLUTION OF THIS LINE OF SHOWERS AND
STORMS AFTER SUNRISE TODAY THAN THE HRRR...SO THOSE TWO MODELS WERE
USED TO CREATE THE NEW FORECAST. THE MODELS SUGGEST A STRONG COLD
FRONT WILL MOVE ACROSS CENTRAL AND EASTERN KENTUCKY TODAY...WITH THE
BOUNDARY EXITING THE AREA LATE THIS AFTERNOON. WIDESPREAD SHOWERS AND
STORMS ARE EXPECTED TO CONTINUE FIRING ALONG AND JUST AHEAD OF THIS
FRONT...WITH THE PEAK IN ACTIVITY OCCURRING BETWEEN ROUGHLY NOON AND
5 PM. THE LATEST FORECAST SOUNDINGS CONTINUE TO SUPPORT THE POTENTIAL
FOR LOCALLY HEAVY RAINFALL...WITH PRECIPITABLE WATER VALUES OF AROUND
2 INCHES PERSISTING THROUGH THE OVERNIGHT HOURS. SOME OF THE STRONGER
THUNDERSTORMS COULD ALSO PRODUCE GUSTY WINDS...BUT LOCALLY HEAVY
RAINFALL WILL BE THE PRIMARY THREAT. THE RAIN CHANCES WILL NOT END
ONCE THE FRONT HAS PASSED BY US...HOWEVER. THE BOUNDARY IS EXPECTED
TO STALL ACROSS THE TENNESSEE VALLEY ON FRIDAY. WAVES OF LOW PRESSURE
ARE THEN PROGGED TO MIGRATE FROM WEST TO EAST ALONG THE FRONT. THESE
DISTURBANCES WILL BRING ENOUGH LIFT AND MOISTURE TO LOCATIONS SOUTH
OF THE MOUNTAIN PARKWAY TO PERHAPS FIRE OFF ISOLATED TO SCATTERED
RAIN SHOWERS LATE TONIGHT THROUGH THE END OF THE DAY ON FRIDAY.
ONCE THE FRONT MOVES THROUGH EARLY TONIGHT...AN UNSEASONABLY COOL
CANADIAN AIR MASS WILL SETTLE OVER THE AREA. THIS AIR MASS WILL BRING
FALL LIKE TEMPERATURES TO EASTERN KENTUCKY TONIGHT AND FRIDAY. THE
COOL WEATHER WILL FIRST BE EXPERIENCED LATE TONIGHT...AS WINDS SHIFT
TO THE NORTH AND THE COOL AIR FULLY INVADES THE REGION. TONIGHTS
LOWS ARE EXPECTED TO BOTTOM OUT IN THE LOW TO MID 60S FOR MOST
LOCATIONS. FOLKS ALONG AND NORTH OF THE I-64 CORRIDOR MAY SEE THE
MERCURY DIP INTO THE UPPER 50S BY FRIDAY MORNING. HIGH TEMPERATURES
ON FRIDAY WILL LIKELY ONLY CLIMB INTO THE LOW TO MID 70S ACROSS THE
AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 431 AM EDT THU SEP 11 2014
THE MODELS ARE IN GOOD AGREEMENT WITH THE LONG WAVE PATTERN THROUGH
THE PERIOD. PROGRESSIVE AND AMPLIFIED FLOW WILL CONTROL ACROSS THE
NORTHERN HALF OF THE CONUS AS SEVERAL PASSING SHORT WAVES HELP TO
REINFORCE TROUGHING ACROSS THE REGION. UPPER LEVEL RIDGING HANGING ON
ACROSS THE SOUTHERN CONUS WILL GRADUALLY DAMPEN AND GET SUPPRESSED
FURTHER SOUTH INTO EARLY NEXT WEEK...BEFORE CONSOLIDATING MORE ACROSS
THE DESERT SOUTHWEST BY THE MIDDLE OF NEXT WEEK.
FOR EASTERN KENTUCKY...THE FIRST MAIN SHORT WAVE WILL MOVE THROUGH
FRIDAY NIGHT INTO SATURDAY...BRINGING A CHANCE OF SHOWERS. GENERALLY
DRY WEATHER CAN BE EXPECTED FROM SATURDAY NIGHT THROUGH SUNDAY
NIGHT...AS HIGH PRESSURE TEMPORARILY BUILDS IN AT THE SURFACE. A
DEEPER TROUGH AXIS...WITH SOME SURFACE DEVELOPMENT NOTED BY THE
MODELS...WILL THEN AFFECT THE AREA FROM MONDAY THROUGH
TUESDAY. THIS SYSTEM WILL BRING SOME RENEWED CHANCES OF
SHOWERS...ALTHOUGH THERE WILL NOT BE AS MUCH LOW LEVEL MOISTURE TO
WORK WITH...SO STUCK FAIRLY CLOSE TO THE BLENDED GUIDANCE ON THE
POPS. DRY WEATHER WILL ENSUE ONCE AGAIN THEREAFTER...AS SURFACE HIGH
PRESSURE BUILDS IN ACROSS THE OHIO VALLEY.
TEMPERATURES WILL AVERAGE BELOW NORMAL THROUGH THE PERIOD...WITH
HIGHS MAINLY IN THE LOW TO MID 70S AND LOWS IN THE 50S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 645 AM EDT THU SEP 11 2014
WIDESPREAD SHOWERS AND STORMS WILL LOCALLY HEAVY RAINFALL AND GUSTY
WINDS ARE STILL ON TAP TODAY AT ALL FOUR TAF SITES. MVFR AND AT TIMES
IFR CONDITIONS WILL BE POSSIBLE DUE TO HEAVY RAINFALL AND FOG WITH
SHOWERS AND STORMS TODAY. THE RAIN IS EXPECTED TO LAST ALL DAY BEFORE
TAPERING OFF THIS EVENING. WINDS ARE EXPECTED TO SHIFT TO TO THE WEST
LATE THIS AFTERNOON AND THEN TO THE NORTH THIS EVENING AS THE FRONT
MOVES PAST. LOW LEVEL CLOUD COVER WILL LIKELY PLAGUE THE TAF SITES
THROUGH TOMORROW MORNING AS THE FRONT STALLS OUT TO OUR SOUTH AND
MOIST AIR CONTINUES TO RIDE UP AND OVER THE BOUNDARY. ISOLATED RAIN
SHOWERS WILL ALSO LINGER OVERNIGHT INTO EARLY TOMORROW...PARTICULARLY
NEAR LOZ AND SME...WHICH WILL BE CLOSER TO THE FRONT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AR
SHORT TERM...AR
LONG TERM...GEOGERIAN
AVIATION...AR
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
1059 AM CDT Thu Sep 11 2014
.UPDATE:
Issued at 1059 AM CDT Thu Sep 11 2014
Mainly cloudy skies are expected the rest of the afternoon. The
latest RAP soundings are showing moisture being trapped below a
inversion at 900mb. This will keep temperatures from climbing much
this afternoon given the clouds and northerly winds. Fewer locations
are reporting drizzle this last hour, so I expect this trend
should continue into the afternoon as the ceilings increase.
Britt
&&
.SHORT TERM: (Through Late This Afternoon)
Issued at 340 AM CDT Thu Sep 11 2014
A strong surface cold front has moved completely southeast of our
region early this morning with an extensive area of low clouds in
its wake. The radar mosaic showed the northern edge of the rain was
barely edging our region into southern Reynolds and Madison counties
in MO. The center of the airmass responsible for this cold front
was still well to the northwest of us over southern Alberta province
meaning this airmass will take considerable time to build into our
area and remain around for awhile. Temps have dipped into the 50s
for many areas north of Interstate 70, but remain in the 60s and
even lower 70s elsewhere.
A strong storm system at the upper levels will dig in across Montana
and Wyoming today and actually back the flow across our region to a
bit more southwesterly than what it is currently. This should cause
the surface front to become quasi-stationary, but still remain well
to our south. However, the better moisture in tow behind the front
will likely remain across much of southeastern MO and far southern
IL thru today. Models loosely depict a wave riding along the
stalling frontal boundary later today--more specifically late this
morning and early this afternoon--which looks to be a sufficiently
northern enough track to justify some mentionable PoP throughout a
good portion of the day in the far southern CWA in southeastern MO.
Otherwise, the atmosphere drys out enough to go with a dry forecast.
Based on PIREPs from last evening, the thickness of the cloud layer
currently over us is about 2500ft. We are less than two weeks from
the autumnal equinox and with a rather persistently decent CAA at
the low levels expected, expect this low cloud to be a bit of a
foretaste to the more stubborn cloud cover we will encounter more
frequently during the colder months. Favored a more pessimistic
cloud cover forecast a la the RAP which doesn`t really start to
break things up until later this afternoon and even then may re-gel
together tonight.
Cloudy skies for much of the day will keep temps down and this looks
like it is well handled with the 00z MOS, with maxes in the 60s.
TES
.LONG TERM: (Tonight through Wednesday)
Issued at 340 AM CDT Thu Sep 11 2014
The shortwave now diving into Montana will move into the northeast
Plains and Upper Midwest Friday. Latest guidance is in good
agreement with the speed and track of the wave as it passes north of
the area. Most of the synoptic scale lift ahead of the shortwave
will pass north of the CWFA, but we will be in the right rear
quadrant of the upper level jet and both the GFS and NAM are also
showing bands of frontogenetical forcing moving through Friday
afternoon and Friday night. Corresponding light QPF is being
produced by the models, so feel pretty confident there will be some
light rain. However am not sure how much of this precip will be
measurable so am sticking with slight chance to mid chance PoPs
Friday afternoon through Friday night as this wave moves through.
Zonal flow aloft with a 1030mb Canadian high pressure will control
the weather for the weekend. Expect this to provide the Bi-State
region with spectacular weather for those who enjoy Autumn, with
highs mainly in the mid 60s to low 70s and lows in the 40s.
Medium range guidance is indicating a pattern shift in the
atmosphere over us toward mid-week from quasi-zonal to northwest
flow aloft. The initial wave which will dig into the eastern CONUS
is forecast to pass over the Midwest Monday into Monday night. Much
like Friday`s wave, the broad synoptic lift associated with the wave
should pass north of us with a band of low level frontogenetical
forcing ahead of another cold front. Feel low chance PoPs continue
to be indicated for Monday and Monday night as this forcing affects
the region, and higher PoPs may be needed if the shortwave turns out
to be stronger than currently forecast. Another shot of Canadian
air will shift across the Midwest Tuesday into the Ohio Valley
Wednesday. Stuck close to guidance for temperatures with highs in
the 70s and lows in the 50s which continue to be below
climatology...although it may not be cool enough given the falling
heights and easterly flow as the high moves east of the area.
Carney
&&
.AVIATION: (For the 12z TAFs through 12z Friday Morning)
Issued at 652 AM CDT Thu Sep 11 2014
MVFR ceilings are expected to prevail at the TAF sites thru much,
if not all, of the valid period. For early this morning, also
expect brief periods of drizzle mixed in with some lower ceilings,
perhaps to IFR levels. Otherwise, northerly surface winds between
5 and 10 knots will continue.
Specifics for KSTL: MVFR ceilings thru the period. Brief periods
of drizzle and IFR ceilings also expected with this becoming less
likely heading into late morning. Otherwise, northerly winds
around 10 knots.
TES
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
652 AM CDT Thu Sep 11 2014
.SHORT TERM: (Through Late This Afternoon)
Issued at 340 AM CDT Thu Sep 11 2014
A strong surface cold front has moved completely southeast of our
region early this morning with an extensive area of low clouds in
its wake. The radar mosaic showed the northern edge of the rain was
barely edging our region into southern Reynolds and Madison counties
in MO. The center of the airmass responsible for this cold front
was still well to the northwest of us over southern Alberta province
meaning this airmass will take considerable time to build into our
area and remain around for awhile. Temps have dipped into the 50s
for many areas north of Interstate 70, but remain in the 60s and
even lower 70s elsewhere.
A strong storm system at the upper levels will dig in across Montana
and Wyoming today and actually back the flow across our region to a
bit more southwesterly than what it is currently. This should cause
the surface front to become quasi-stationary, but still remain well
to our south. However, the better moisture in tow behind the front
will likely remain across much of southeastern MO and far southern
IL thru today. Models loosely depict a wave riding along the
stalling frontal boundary later today--more specifically late this
morning and early this afternoon--which looks to be a sufficiently
northern enough track to justify some mentionable PoP throughout a
good portion of the day in the far southern CWA in southeastern MO.
Otherwise, the atmosphere drys out enough to go with a dry forecast.
Based on PIREPs from last evening, the thickness of the cloud layer
currently over us is about 2500ft. We are less than two weeks from
the autumnal equinox and with a rather persistently decent CAA at
the low levels expected, expect this low cloud to be a bit of a
foretaste to the more stubborn cloud cover we will encounter more
frequently during the colder months. Favored a more pessimistic
cloud cover forecast a la the RAP which doesn`t really start to
break things up until later this afternoon and even then may re-gel
together tonight.
Cloudy skies for much of the day will keep temps down and this looks
like it is well handled with the 00z MOS, with maxes in the 60s.
TES
.LONG TERM: (Tonight through Wednesday)
Issued at 340 AM CDT Thu Sep 11 2014
The shortwave now diving into Montana will move into the northeast
Plains and Upper Midwest Friday. Latest guidance is in good
agreement with the speed and track of the wave as it passes north of
the area. Most of the synoptic scale lift ahead of the shortwave
will pass north of the CWFA, but we will be in the right rear
quadrant of the upper level jet and both the GFS and NAM are also
showing bands of frontogenetical forcing moving through Friday
afternoon and Friday night. Corresponding light QPF is being
produced by the models, so feel pretty confident there will be some
light rain. However am not sure how much of this precip will be
measurable so am sticking with slight chance to mid chance PoPs
Friday afternoon through Friday night as this wave moves through.
Zonal flow aloft with a 1030mb Canadian high pressure will control
the weather for the weekend. Expect this to provide the Bi-State
region with spectacular weather for those who enjoy Autumn, with
highs mainly in the mid 60s to low 70s and lows in the 40s.
Medium range guidance is indicating a pattern shift in the
atmosphere over us toward mid-week from quasi-zonal to northwest
flow aloft. The initial wave which will dig into the eastern CONUS
is forecast to pass over the Midwest Monday into Monday night. Much
like Friday`s wave, the broad synoptic lift associated with the wave
should pass north of us with a band of low level frontogenetical
forcing ahead of another cold front. Feel low chance PoPs continue
to be indicated for Monday and Monday night as this forcing affects
the region, and higher PoPs may be needed if the shortwave turns out
to be stronger than currently forecast. Another shot of Canadian
air will shift across the Midwest Tuesday into the Ohio Valley
Wednesday. Stuck close to guidance for temperatures with highs in
the 70s and lows in the 50s which continue to be below
climatology...although it may not be cool enough given the falling
heights and easterly flow as the high moves east of the area.
Carney
&&
.AVIATION: (For the 12z TAFs through 12z Friday Morning)
Issued at 652 AM CDT Thu Sep 11 2014
MVFR ceilings are expected to prevail at the TAF sites thru much,
if not all, of the valid period. For early this morning, also
expect brief periods of drizzle mixed in with some lower ceilings,
perhaps to IFR levels. Otherwise, northerly surface winds between
5 and 10 knots will continue.
Specifics for KSTL: MVFR ceilings thru the period. Brief periods
of drizzle and IFR ceilings also expected with this becoming less
likely heading into late morning. Otherwise, northerly winds
around 10 knots.
TES
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1006 AM CDT THU SEP 11 2014
.UPDATE...
ISSUED AT 1006 AM CDT THU SEP 11 2014
CLOUDS ARE BEGINNING TO BREAK OVER WESTERN AND CENTRAL NORTH
DAKOTA. TEMPERATURES ARE RESPONDING BY JUMPING INTO THE 40S WITHIN
THE LAST HOUR. BOWMAN RADAR SHOWS ALL RETURNS SOUTH OF THE STATE.
HOWEVER...MAINTAINED CHANCE OF LIGHT RAIN SOUTHWEST THROUGH THE
THE MORNING AS A BAROCLINIC ZONE WILL BE IN THE VICINITY.
ELSEWHERE...THE LATEST ARW AND NMM MESOSCALE MODELS PROG ISOLATED
TO SCATTERED SHOWER ACTIVITY DEVELOPING SOUTHWEST OF THE MISSOURI
RIVER THIS AFTERNOON. THE LATEST HRRR PROGS ISOLATED SHOWERS
DEVELOPING CWA-WIDE THIS AFTERNOON. GIVEN THE PROXIMITY OF THE
MOISTURE AND SUBTLE MUCAPE...WILL KEEP AFTERNOON POPS CONFINED TO
AREAS SOUTHWEST OF THE MISSOURI RIVER...SIMILAR TO THE ARW AND NMM
SOLUTIONS. AS A RESULT...CHANGED AFTERNOON WEATHER PRECIP TYPE
WORDING FROM STRATIFORM RAIN TO CONVECTIVE SHOWERS. THE UPDATED
PRODUCTS WILL BE OUT SHORTLY.
UPDATE ISSUED AT 645 AM CDT THU SEP 11 2014
LATEST SATELLITE IMAGERY SHOWS UPPER LEVEL TROUGH DROPPING SOUTH
THROUGH THE NORTHERN ROCKIES WITH STRONG JET EXTENDING FROM THE
BASE OF THE TROUGH EAST INTO THE NORTHERN PLAINS. LATEST RADAR
IMAGERY INDICATES THE MAJORITY OF THE PRECIPITATION REMAINING
SOUTH OF THE FORECAST AREA...WITH FAR SOUTHWEST BOWMAN COUNTY
SEEING SOME LIGHT RETURNS. MADE SOME MINOR ADJUSTMENTS TO
POPS...CONFINING THEM TO THE FAR SOUTHWEST EARLY THIS MORNING. IF
WE SEE SOME BREAKS IN THE CLOUDS TODAY...STRONG LOW LEVEL LAPSE
RATES SHOULD AID IN SHOWER DEVELOPMENT FARTHER NORTH AND EAST.
LATEST HRRR DEVELOPS ISOLATED CONVECTION ACROSS THE CWA BY THIS
AFTERNOON. FOR NOW WILL KEEP POPS LIMITED TO THE SOUTHWEST QUARTER
AS PREVIOUSLY FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 346 AM CDT THU SEP 11 2014
FREEZING TEMPERATURES TONIGHT HIGHLIGHT THE SHORT TERM FORECAST.
THE 00 UTC DETERMINISTIC SUITE SUGGESTS THE CURRENT STRATUS DECK
IN PLACE THIS MORNING ACROSS WESTERN AND CENTRAL NORTH DAKOTA WILL
BEGIN TO CLEAR ACROSS THE FAR NORTH LATE THIS AFTERNOON. THE
CLEARING TREND IS FORECAST TO CONTINUE TO PUSH SOUTH THROUGH THE
EVENING AS THE SURFACE HIGH ACROSS WESTERN SASKATCHEWAN THIS
MORNING PROPAGATES INTO WESTERN SOUTH DAKOTA FRIDAY MORNING.
GIVEN COOL TEMPERATURES IN THE 40S AND LOWER 50S TO BEGIN THE
EVENING...WIDESPREAD LOWS IN THE UPPER 20S AND LOWER 30S ARE EXPECTED
ACROSS MUCH OF WESTERN AND CENTRAL NORTH DAKOTA TONIGHT WITH
RADIATIONAL COOLING. THUS HAVE ISSUED A FREEZE WARNING FOR MUCH OF
THE AREA LATE TONIGHT INTO FRIDAY MORNING..OUTSIDE OF THE JAMES
RIVER VALLEY AND FAR SOUTH CENTRAL. FOR THESE AREAS...SUFFICIENT
CLOUD COVER IS EXPECTED TO REMAIN THROUGH THE NIGHT TO KEEP LOWS
ABOVE FREEZING. HOWEVER...A FROST ADVISORY MAY BE NEEDED WITH
LATER UPDATES.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 346 AM CDT THU SEP 11 2014
A MEAN EASTERN PACIFIC/WESTERN U.S RIDGE AND CENTRAL/EASTERN U.S.
TROUGH PATTERN IS EXPECTED TO CONTINUE THROUGH THE LONG TERM PERIOD.
NORTHWEST FLOW OVER THE NORTHERN PLAINS WILL BRING A SERIES OF WEAK
SHORTWAVES DOWN THE LEE OF THE CANADIAN ROCKIES AND INTO THE
FORECAST AREA...KEEPING DAYTIME HIGH TEMPERATURES MAINLY IN THE
60S...WITH A THREAT OF PATCHY FROST EACH MORNING INTO EARLY NEXT
WEEK. THE WESTERN RIDGE FINALLY TRANSLATES INLAND NEXT WEEK BRINGING
UPPER LEVEL RIDGING AND WARMER TEMPERATURES...MAINLY 70S...TO THE
FORECAST AREA NEXT TUESDAY THROUGH THURSDAY. COULD SEE AN ISOLATED
SHOWER ALONG THE INTERNATIONAL BORDER SATURDAY EVENING...OTHERWISE
DRY CONDITIONS ARE ANTICIPATED THROUGH THE EXTENDED PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 645 AM CDT THU SEP 11 2014
GENERALLY VFR STRATUS WILL PERSIST THROUGH MORNING ACROSS WESTERN
AND CENTRAL NORTH DAKOTA...BEFORE SLOWLY CLEARING FROM NORTH TO
SOUTH LATE THIS AFTERNOON AND INTO THE EVENING. CANNOT RULE OUT A
BRIEF PERIOD OF MVFR CONDITIONS IN STRATUS...WITH LIGHT RAIN
POSSIBLY MIXED WITH SNOW THIS MORNING AT KDIK.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM 1 AM CDT /MIDNIGHT MDT/ TO 10 AM CDT /9 AM
MDT/ FRIDAY FOR NDZ001>005-009>013-017>022-031>035-040>044.
&&
$$
UPDATE...TM
SHORT TERM...AYD
LONG TERM...TWH
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
645 AM CDT THU SEP 11 2014
.UPDATE...
ISSUED AT 645 AM CDT THU SEP 11 2014
LATEST SATELLITE IMAGERY SHOWS UPPER LEVEL TROUGH DROPPING SOUTH
THROUGH THE NORTHERN ROCKIES WITH STRONG JET EXTENDING FROM THE
BASE OF THE TROUGH EAST INTO THE NORTHERN PLAINS. LATEST RADAR
IMAGERY INDICATES THE MAJORITY OF THE PRECIPITATION REMAINING
SOUTH OF THE FORECAST AREA...WITH FAR SOUTHWEST BOWMAN COUNTY
SEEING SOME LIGHT RETURNS. MADE SOME MINOR ADJUSTMENTS TO
POPS...CONFINING THEM TO THE FAR SOUTHWEST EARLY THIS MORNING. IF
WE SEE SOME BREAKS IN THE CLOUDS TODAY...STRONG LOW LEVEL LAPSE
RATES SHOULD AID IN SHOWER DEVELOPMENT FARTHER NORTH AND EAST.
LATEST HRRR DEVELOPS ISOLATED CONVECTION ACROSS THE CWA BY THIS
AFTERNOON. FOR NOW WILL KEEP POPS LIMITED TO THE SOUTHWEST QUARTER
AS PREVIOUSLY FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 346 AM CDT THU SEP 11 2014
FREEZING TEMPERATURES TONIGHT HIGHLIGHT THE SHORT TERM FORECAST.
THE 00 UTC DETERMINISTIC SUITE SUGGESTS THE CURRENT STRATUS DECK
IN PLACE THIS MORNING ACROSS WESTERN AND CENTRAL NORTH DAKOTA WILL
BEGIN TO CLEAR ACROSS THE FAR NORTH LATE THIS AFTERNOON. THE
CLEARING TREND IS FORECAST TO CONTINUE TO PUSH SOUTH THROUGH THE
EVENING AS THE SURFACE HIGH ACROSS WESTERN SASKATCHEWAN THIS
MORNING PROPAGATES INTO WESTERN SOUTH DAKOTA FRIDAY MORNING.
GIVEN COOL TEMPERATURES IN THE 40S AND LOWER 50S TO BEGIN THE
EVENING...WIDESPREAD LOWS IN THE UPPER 20S AND LOWER 30S ARE EXPECTED
ACROSS MUCH OF WESTERN AND CENTRAL NORTH DAKOTA TONIGHT WITH
RADIATIONAL COOLING. THUS HAVE ISSUED A FREEZE WARNING FOR MUCH OF
THE AREA LATE TONIGHT INTO FRIDAY MORNING..OUTSIDE OF THE JAMES
RIVER VALLEY AND FAR SOUTH CENTRAL. FOR THESE AREAS...SUFFICIENT
CLOUD COVER IS EXPECTED TO REMAIN THROUGH THE NIGHT TO KEEP LOWS
ABOVE FREEZING. HOWEVER...A FROST ADVISORY MAY BE NEEDED WITH
LATER UPDATES.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 346 AM CDT THU SEP 11 2014
A MEAN EASTERN PACIFIC/WESTERN U.S RIDGE AND CENTRAL/EASTERN U.S.
TROUGH PATTERN IS EXPECTED TO CONTINUE THROUGH THE LONG TERM PERIOD.
NORTHWEST FLOW OVER THE NORTHERN PLAINS WILL BRING A SERIES OF WEAK
SHORTWAVES DOWN THE LEE OF THE CANADIAN ROCKIES AND INTO THE
FORECAST AREA...KEEPING DAYTIME HIGH TEMPERATURES MAINLY IN THE
60S...WITH A THREAT OF PATCHY FROST EACH MORNING INTO EARLY NEXT
WEEK. THE WESTERN RIDGE FINALLY TRANSLATES INLAND NEXT WEEK BRINGING
UPPER LEVEL RIDGING AND WARMER TEMPERATURES...MAINLY 70S...TO THE
FORECAST AREA NEXT TUESDAY THROUGH THURSDAY. COULD SEE AN ISOLATED
SHOWER ALONG THE INTERNATIONAL BORDER SATURDAY EVENING...OTHERWISE
DRY CONDITIONS ARE ANTICIPATED THROUGH THE EXTENDED PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 645 AM CDT THU SEP 11 2014
GENERALLY VFR STRATUS WILL PERSIST THROUGH MORNING ACROSS WESTERN
AND CENTRAL NORTH DAKOTA...BEFORE SLOWLY CLEARING FROM NORTH TO
SOUTH LATE THIS AFTERNOON AND INTO THE EVENING. CANNOT RULE OUT A
BRIEF PERIOD OF MVFR CONDITIONS IN STRATUS...WITH LIGHT RAIN
POSSIBLY MIXED WITH SNOW THIS MORNING AT KDIK.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM 1 AM CDT /MIDNIGHT MDT/ TO 10 AM CDT /9 AM
MDT/ FRIDAY FOR NDZ001>005-009>013-017>022-031>035-040>044.
&&
$$
UPDATE...TWH
SHORT TERM...AYD
LONG TERM...TWH
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
958 AM CDT THU SEP 11 2014
.UPDATE...
SEE DISCUSSION FOR MORNING UPDATE.
&&
.DISCUSSION...
NOT MANY CHANGES TO THIS MORNINGS FORECAST. WATER VAPOR CLEARLY
SHOWS TROPICAL WAVE MARCHING WEST THIS MORNING. SURFACE COLD FRONT IS
CURRENTLY RIGHT ON THE DALLAS/ FORT WORTH DOOR STEP. A LINE OF
SHOWERS AND THUNDERSTORMS HAS FORMED JUST AHEAD OF THE FRONT. FOR
SOUTHEAST TEXAS THE FRONT WILL REMAIN NORTH OF THE AREA THIS
AFTERNOON UNTIL THE SHORTWAVE IN MONTANA CAN PUSH FARTHER SOUTH
THIS EVENING. MOISTURE VALUES REMAIN NEAR AVERAGE FOR THE AREA
WITH CONVECTIVE TEMPERATURES IN THE UPPER 80S. HIGH RES MODELS
SHOWING SOME SHOWERS AND THUNDERSTORMS FORMING ALONG A SEA BREEZE
THIS AFTERNOON. CURRENT FORECAST HAS THIS COVERED. ONLY MADE MINOR
TWEAKS TO ACCOUNT FOR TRENDS. 23
&&
.PREV DISCUSSION... /ISSUED 358 AM CDT THU SEP 11 2014/
DISCUSSION...
SURFACE COLD FRONT MADE SOME MORE PROGRESS EARLIER TONIGHT BEFORE
LOOSING STEAM OVER THE LAST COUPLE OF HOURS. AS OF CURRENT THE
FRONT WAS LOCATED JUST NORTH OF THE DALLAS/ FORT WORTH AREA. A 0Z
500 MB HAND ANALYSIS REVEALED A POTENT SHORTWAVE DIVING SOUTH
OVER MONTANA. AT 250MB RIDGING HAS STARTED TO FLATTEN AS A TROUGH
AXIS PUSHES IN FROM THE WEST. FOR TODAY MODELS ARE SHOWING A BIT
MORE COVERAGE THAN PREVIOUSLY ADVERTISED. CURRENT PWAT VALUES...
COURTESY OF GPS MET SITE... ARE AROUND 1.60". GFS FORECAST
SOUNDINGS FOR THIS AFTERNOON SHOW PWAT VALUES AROUND 1.7" WITH K
INDEX VALUES NEAR 30 WHILE THE NAM IS SLIGHTLY MORE AGGRESSIVE.
THE RIDGE SHOULD CONTINUE TO FLATTEN THIS AFTERNOON SO WILL LEAN
TO THE SLIGHTLY MORE AGGRESSIVE NAM. HIGH RES MODELS ALSO SUPPORT
THIS WITH CHANCE COVERAGE ALONG THE COAST. THE FRONT SHOULD REMAIN
NORTH OF THE AREA THIS AFTERNOON BUT THE RAP IS DEVELOPING PRECIP
ALONG THE FRONT AND PUSHING IT INTO OUR NORTHERN ZONES THIS AFTERNOON.
THIS EVENING INTO FRIDAY SOME CONVECTION COULD MAKE IT INTO OUR
NORTHERN ZONES BEFORE DISSIPATING. FRIDAY MORNING A TROPICAL WAVE
CURRENTLY LOCATED NEAR FLORIDA WILL APPROACH THE MEXICAN COAST
LINE. AS THE TROPICAL WAVE MOVES WEST IT WILL BRING VERY MOIST AIR
WITH IT. PWATS SURGE TOWARDS 2.20" FRIDAY AFTERNOON INTO SATURDAY.
AT THE SAME TIME THE FRONT CURRENTLY NORTH OF DALLAS/ FORT WORTH
WILL FINALLY MOVE INTO THE AREA. UPPER LEVEL SUPPORT FOR THIS
SYSTEM IS WEAK THOUGH. THE SHORTWAVE CURRENTLY DIVING SOUTH IN
MONTANA WILL QUICKLY START TO PULL TO THE EAST FRIDAY WHICH WILL
HELP TO STALL AND WASH OUT THE FRONT OVER OUR AREA FRIDAY EVENING
INTO SATURDAY MORNING. RAIN CHANCES WILL QUICKLY START TO RISE
FRIDAY AS THE WAVE APPROACHES. LIFT WILL COME FROM THE SURFACE
BOUNDARY AND SPEED CONVERGENCE AT 850MB. GIVEN VERY HIGH MOISTURE
VALUES AND LIFT RAIN LOOKS LIKELY FRIDAY EVENING INTO SATURDAY.
OMEGA VALUES FROM BOTH THE GFS AND NAM ALSO SUPPORT THIS. AS OF
CURRENT IT LOOKS THAT RAIN WILL START FRIDAY MORNING OVER THE
WATERS (IN ASSOCIATION WITH THE APPROACHING TROPICAL WAVE) AND
JUST NORTH OF THE AREA (IN ASSOCIATION WITH THE FRONT). RAIN WILL
THEN MOVE INLAND ALONG A SEA BREEZE AND POSSIBLY COLLIDE WITH ON
GOING SHOWERS AND THUNDERSTORMS WITH THE SURFACE FRONT TO THE
NORTH. THE EXACT LOCATION OF THE FRONT AND EXTENT OF PRECIPITATION
OVER THE WATERS COULD GREATLY INFLUENCE THE EVENTUAL DISTRIBUTION
OF RAINFALL. WITH THE WEAK STEERING FLOW THE CHANCE FOR HEAVY
RAIN REMAINS POSSIBLE FRIDAY AFTERNOON INTO SATURDAY MORNING.
ABOVE AVERAGE MOISTURE VALUES ARE EXPECTED TO REMAIN OVER THE AREA
THROUGH THE WEEKEND ALLOWING THE CHANCE OF RAIN TO CONTINUE.
MODELS DUE STRUGGLE ON HOW TO HANDLE THE REMNANT ENERGY OF THE
WAVE THOUGH AS IT MOVES INTO MEXICO. IN GENERAL MODELS MOVE THE
ENERGY NORTH AROUND A WEAK UPPER LEVEL RIDGE AND PICK IT BACK UP
IN THE FLOW. THE NAM MOVES PIECES OF POSITIVE VORTICITY OVER OUR
AREA SATURDAY EVENING WHILE THE GFS KEEPS THE ENERGY WEST OF US.
WHERE THIS LEFTOVER ENERGY MOVES NORTH WILL AFFECT WHERE THE
GREATEST CHANCES OF RAIN WILL BE SATURDAY INTO SUNDAY. BY NEXT
WEEK THE UPPER LEVEL FLOW WILL AMPLIFY A BIT OVER THE EASTERN
UNITED STATES ALLOWING MID LEVEL WINDS TO TURN FROM THE NORTHWEST
OVER SOUTHEAST TEXAS. THIS WILL ALSO ALLOW UPPER LEVEL
DISTURBANCES TO MOVE OVER THE AREA. THE BEST CHANCES OF RAIN WILL
BE IN THE AFTERNOON OF EACH DAY NEXT WEEK THANKS TO DAY TIME
HEATING. HAVE TRENDED POPS UP IN THE AFTERNOON FOR NEXT WEEK TO
ACCOUNT FOR THIS. 23
MARINE...
TYPICAL SUMMER LIKE PATTERN TODAY WITH ISO/SCT PRECIP IN COASTAL
WATERS IN THE MORNING HOURS, LIGHT-MODERATE SE WINDS AND LOW SEAS.
ERLY WAVE IN THE GULF WILL TRANSPORT INCREASED MOISTURE LEVELS INTO
THE WATERS LATER TONIGHT LEADING TO MORE AREAL PRECIP COVERAGE FRI
MORNING. AS THE WAVE APPROACHES THE WESTERN GULF COASTLINE FRI NIGHT
& SATURDAY...LOOK FOR WINDS TO INCREASE, BECOME MORE ERLY AND SEAS
TO BUILD. MAY NEED CAUTION FLAGS DURING THIS TIME. MODERATE ENE FLOW
AND RAIN CHANCES SHOULD PERSIST THRU THE WEEKEND AS GRADIENT
TIGHTENS NEAR THE COAST COMPLIMENTS OF A FRONTAL BOUNDARY LINGERING
IN THE REGION. 47
AVIATION...
HIGHER MOISTURE LEVELS HUGGING THE COAST WILL LEAD TO ISO/SCT PRECIP THERE
AND IN THE COASTAL COUNTIES THRU LATE MORNING. IT SHOULD CREEP INLAND TODAY
WITH DAYTIME HEATING AND EXPAND INTO METRO TAF SITES FROM LATE MORNING-LATE
AFTN. INCLUDED SOME VCSH`S FOR NOW. FRONTAL BOUNDARY MOVING INTO N TX SHOULD
PROVIDE A FOCUS FOR SOME TSRA LATER TODAY BUT SUSPECT MOST WILL REMAIN N OF CLL
THRU THE TAF PERIOD SO NO MENTION THERE YET. DO ANTICIPATE A DEEPER SURGE OF
MOISTURE TO MOVE INTO THE COASTAL WATERS PRIOR TO SUNRISE FRI AND EXPECT FAIRLY
GOOD CHANCES OF PRECIP S OF I-10 BETWEEN 10-18Z FRI...FOLLOWED BY MORE COVERAGE
FRI AFTN (BEYOND 12Z TAF). OUTSIDE OF PRECIP MAINLY VFR CONDITIONS SHOULD
PREVAIL. 47
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 97 75 90 71 84 / 20 30 60 60 40
HOUSTON (IAH) 96 77 91 73 86 / 30 30 60 60 50
GALVESTON (GLS) 91 82 90 79 86 / 20 30 60 60 60
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...23
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
335 PM MST THU SEP 11 2014
.UPDATE...UPDATED FIRE WEATHER DISCUSSION.
&&
.SYNOPSIS...
THE COMBINATION OF A RATHER DRY AIRMASS AND HIGH PRESSURE ALOFT IS
EXPECTED TO KEEP SKIES MAINLY CLEAR OVER THE REGION THROUGH FRIDAY.
A VERY SLOW INCREASE IN MOISTURE WILL BEGIN LATE FRIDAY...THEN
CONTINUE INTO THE WEEKEND...AND INTO NEXT WEEK AS THE FLOW ALOFT
BECOMES MORE SOUTHEASTERLY. THIS WILL LEAD TO INCREASED CHANCES OF
SHOWERS AND THUNDERSTORMS...INITIALLY OVER MOUNTAINOUS AREAS OVER
THE WEEKEND...BUT POSSIBLY SPREADING INTO LOWER DESERT LOCATIONS BY
EARLY NEXT WEEK.
&&
.DISCUSSION...
LATEST RAP STREAMLINE ANALYSIS SHOWS A WEAK UPPER LEVEL TROUGH
SITUATED ACROSS AZ. SOMEWHAT DEEPER MOISTURE IS EVIDENT ON WV
IMAGERY EAST OF THE TROUGH ACROSS SOUTHERN AND EASTERN AZ...THOUGH
REGIONAL SOUNDINGS INDICATE PWATS ARE ONLY IN THE 1.0-1.2 INCH
RANGE.
ISOLATED CU HAS DEVELOPED ACROSS A FEW RIDGETOPS THIS
AFTERNOON...THOUGH A LACK OF CAPE IS LIMITING VERTICAL DEVELOPMENT.
CONSENSUS OF CONVECTIVE ALLOWING MODELS SUGGESTS THAT ISOLATED
SHOWER AND THUNDERSTORM ACTIVITY WILL REMAIN CONFINED TO SOUTHERN
AND EASTERN AZ THIS AFTERNOON.
CONTINUED WARMING AND DRYING TREND EXPECTED FRIDAY AS THE
SUBTROPICAL RIDGE REMAINS THE PREDOMINANT WEATHER FEATURE.
AGAIN...LITTLE CHANCE FOR CONVECTION EXCEPT FOR ISOLATED ACTIVITY IN
THE VICINITY OF THE DEEPEST MOISTURE ACROSS SOUTHEASTERN AZ.
&&
.PREVIOUS DISCUSSION...
SATURDAY AND SUNDAY...
A SLOW INCREASE IN THE AVAILABLE MOISTURE LEVELS IS STILL EXPECTED
TO OCCUR OVER THE UPCOMING WEEKEND AS THE FLOW BELOW 400MB BECOMES
EASTERLY TO SOUTHEASTERLY...AND BEGINS TO PULL MOISTURE BACK INTO
THE REGION. THE GFS IS MOST BULLISH ON THIS MOISTURE
INCREASE...PUSHING PWATS UP TO NEAR 1.50 ON SATURDAY...WHILE THE
EURO KEEPS THEM MAINLY AOB 1.20 INCH. CONSIDERING THAT THE PRIMARY
REASON FOR THE INCREASE IN THE SFC PRESSURE GRADIENT/EASTERLY FLOW
IN THE LOW LEVELS IS THE FACT THAT A RATHER STRONG...AND QUITE COLD
SFC HIGH IS FORECAST TO DIVE SOUTHWARD INTO THE CENTRAL AND SOUTHERN
PLAINS...WITH ITS ORIGINS BEING FROM NORTHERN CANADA/ALASKA...RATHER
THAN A MORE TYPICAL SUBTROPICAL HIGH THAT OFTEN BUILDS OVER THAT
REGION THIS TIME OF YEAR...I AM INCLINED TO GO WITH THE DRIER EURO
FOR NOW. STILL...THERE SHOULD BE ENOUGH MOISTURE/INSTABILITY TO KEEP
SLIGHT CHANCES FOR SHOWERS/THUNDERSTORMS OVER THE HIGHER TERRAIN
NORTH AND EAST OF PHOENIX IN THE FORECAST...BUT WITH MAINLY SINGLE
DIGIT POPS OVER THE LOWER DESERTS. HIGH TEMPERATURES ARE EXPECTED TO
REMAIN MOSTLY IN THE 105-108F RANGE ACROSS SE CA AND SW AZ...BUT
COOL A DEGREE OR TWO OVER SOUTH-CENTRAL AZ AS A BIT OF COOLER AIR
WORKS ITS WAY IN FROM THE EAST.
MONDAY THROUGH WEDNESDAY...
A FURTHER MOISTURE INCREASE IS STILL EXPECTED DURING THIS TIME
PERIOD AS HURRICANE ODILE MOVES NORTHWESTWARD JUST OFF THE WEST
COAST OF BAJA CALIFORNIA. DEEP SE-LY FLOW TO THE EAST AND NORTHEAST
OF ODILE WILL LIKELY PUSH ADDITIONAL MOISTURE NORTHWESTWARD UP THE
GULF OF CALIFORNIA...AND INTO THE DESERT SOUTHWEST. ALTHOUGH THERE
WILL LIKELY BE ENOUGH INCREASE IN AVAILABLE MOISTURE TO TRIGGER AT
LEAST ISOLATED THUNDERSTORMS ACROSS THE LOWER DESERTS OF AZ/SE CA
DURING THIS PERIOD...IT STILL APPEARS THAT WE WILL NOT SEE ANYTHING
CLOSE TO WHAT WE SAW EARLIER THIS WEEK...SINCE LATEST MODEL SUITES
ARE IN VERY STRONG AGREEMENT THAT ODILE WILL TRACK WELL OFF TO OUR
SOUTH AND WEST...EVENTUALLY DISSIPATING OVER THE COOLER WATERS OF
THE EASTERN PACIFIC...WELL OFF THE SOUTHERN CA COAST...WITH MOST OF
ITS ASSOCIATED MOISTURE REMAINING FAR AWAY FROM OUR REGION.
THUS...ONCE AGAIN GOING WITH THE DRIER EURO...WHICH KEEPS OUR PWATS
MAINLY AOB 1.50 INCH THROUGH THIS PERIOD.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...AND
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
NO AVIATION IMPACTS THROUGH FRIDAY MORNING...AS ONLY A FEW AFTERNOON
CU OVER TERRAIN FEATURES WILL PREVAIL ACROSS THE TERMINAL REGION.
SFC WINDS WILL REMAIN VERY LIGHT AOB 10 KT WITH MODERATE CONFIDENCE
OF WIND SHIFT TIMING. IN MANY LOCATIONS AFTER SUNSET...WINDS WILL BE
NEARLY CALM.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...
INCREASING LOW TO MID LEVEL EASTERLY WINDS WILL DEVELOP OVER THE
WEEKEND...HELPING TO SPREAD MONSOONAL MOISTURE AND AN INCREASING
THREAT OF AFTERNOON AND EVENING THUNDERSTORMS BACK OVER THE REGION.
BY SUNDAY A SLIGHT CHANCE OF THUNDERSTORMS IS FORECAST ACROSS THE
ARIZONA DESERTS. HUMIDITY VALUES ACROSS THE DESERTS WILL BEGIN A
STEADY RISE OVER THE WEEKEND AND INTO NEXT WEEK WITH MINIMUM VALUES
FOR MOST AREAS CLIMBING ABOVE 20 PERCENT BY SUNDAY. OVERNIGHT
RECOVERY WILL BE GENERALLY GOOD THROUGH MONDAY WITH MAX HUMIDITY
VALUES CLIMBING ABOVE 50 PERCENT EACH NIGHT...BECOMING GOOD TO
EXCELLENT EARLY NEXT WEEK WITH MANY DESERT LOCALES EXCEEDING 70
PERCENT BY WEDNESDAY MORNING. THE BREEZY EAST WINDS SEEN OVER THE
WEEKEND WILL DIMINISH THROUGH THE MIDDLE OF NEXT WEEK...FAVORING THE
SOUTH TO SOUTHWEST DIRECTIONS AT GENERALLY LESS THAN 15 MPH.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
PREVIOUS DISCUSSION...PERCHA
AVIATION...MO
FIRE WEATHER...MCLANE/CB
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
325 PM MST THU SEP 11 2014
.SYNOPSIS...
THE COMBINATION OF A RATHER DRY AIRMASS AND HIGH PRESSURE ALOFT IS
EXPECTED TO KEEP SKIES MAINLY CLEAR OVER THE REGION THROUGH FRIDAY.
A VERY SLOW INCREASE IN MOISTURE WILL BEGIN LATE FRIDAY...THEN
CONTINUE INTO THE WEEKEND...AND INTO NEXT WEEK AS THE FLOW ALOFT
BECOMES MORE SOUTHEASTERLY. THIS WILL LEAD TO INCREASED CHANCES OF
SHOWERS AND THUNDERSTORMS...INITIALLY OVER MOUNTAINOUS AREAS OVER
THE WEEKEND...BUT POSSIBLY SPREADING INTO LOWER DESERT LOCATIONS BY
EARLY NEXT WEEK.
&&
.DISCUSSION...
LATEST RAP STREAMLINE ANALYSIS SHOWS A WEAK UPPER LEVEL TROUGH
SITUATED ACROSS AZ. SOMEWHAT DEEPER MOISTURE IS EVIDENT ON WV
IMAGERY EAST OF THE TROUGH ACROSS SOUTHERN AND EASTERN AZ...THOUGH
REGIONAL SOUNDINGS INDICATE PWATS ARE ONLY IN THE 1.0-1.2 INCH
RANGE.
ISOLATED CU HAS DEVELOPED ACROSS A FEW RIDGETOPS THIS
AFTERNOON...THOUGH A LACK OF CAPE IS LIMITING VERTICAL DEVELOPMENT.
CONSENSUS OF CONVECTIVE ALLOWING MODELS SUGGESTS THAT ISOLATED
SHOWER AND THUNDERSTORM ACTIVITY WILL REMAIN CONFINED TO SOUTHERN
AND EASTERN AZ THIS AFTERNOON.
CONTINUED WARMING AND DRYING TREND EXPECTED FRIDAY AS THE
SUBTROPICAL RIDGE REMAINS THE PREDOMINANT WEATHER FEATURE.
AGAIN...LITTLE CHANCE FOR CONVECTION EXCEPT FOR ISOLATED ACTIVITY IN
THE VICINITY OF THE DEEPEST MOISTURE ACROSS SOUTHEASTERN AZ.
&&
.PREVIOUS DISCUSSION...
SATURDAY AND SUNDAY...
A SLOW INCREASE IN THE AVAILABLE MOISTURE LEVELS IS STILL EXPECTED
TO OCCUR OVER THE UPCOMING WEEKEND AS THE FLOW BELOW 400MB BECOMES
EASTERLY TO SOUTHEASTERLY...AND BEGINS TO PULL MOISTURE BACK INTO
THE REGION. THE GFS IS MOST BULLISH ON THIS MOISTURE
INCREASE...PUSHING PWATS UP TO NEAR 1.50 ON SATURDAY...WHILE THE
EURO KEEPS THEM MAINLY AOB 1.20 INCH. CONSIDERING THAT THE PRIMARY
REASON FOR THE INCREASE IN THE SFC PRESSURE GRADIENT/EASTERLY FLOW
IN THE LOW LEVELS IS THE FACT THAT A RATHER STRONG...AND QUITE COLD
SFC HIGH IS FORECAST TO DIVE SOUTHWARD INTO THE CENTRAL AND SOUTHERN
PLAINS...WITH ITS ORIGINS BEING FROM NORTHERN CANADA/ALASKA...RATHER
THAN A MORE TYPICAL SUBTROPICAL HIGH THAT OFTEN BUILDS OVER THAT
REGION THIS TIME OF YEAR...I AM INCLINED TO GO WITH THE DRIER EURO
FOR NOW. STILL...THERE SHOULD BE ENOUGH MOISTURE/INSTABILITY TO KEEP
SLIGHT CHANCES FOR SHOWERS/THUNDERSTORMS OVER THE HIGHER TERRAIN
NORTH AND EAST OF PHOENIX IN THE FORECAST...BUT WITH MAINLY SINGLE
DIGIT POPS OVER THE LOWER DESERTS. HIGH TEMPERATURES ARE EXPECTED TO
REMAIN MOSTLY IN THE 105-108F RANGE ACROSS SE CA AND SW AZ...BUT
COOL A DEGREE OR TWO OVER SOUTH-CENTRAL AZ AS A BIT OF COOLER AIR
WORKS ITS WAY IN FROM THE EAST.
MONDAY THROUGH WEDNESDAY...
A FURTHER MOISTURE INCREASE IS STILL EXPECTED DURING THIS TIME
PERIOD AS HURRICANE ODILE MOVES NORTHWESTWARD JUST OFF THE WEST
COAST OF BAJA CALIFORNIA. DEEP SE-LY FLOW TO THE EAST AND NORTHEAST
OF ODILE WILL LIKELY PUSH ADDITIONAL MOISTURE NORTHWESTWARD UP THE
GULF OF CALIFORNIA...AND INTO THE DESERT SOUTHWEST. ALTHOUGH THERE
WILL LIKELY BE ENOUGH INCREASE IN AVAILABLE MOISTURE TO TRIGGER AT
LEAST ISOLATED THUNDERSTORMS ACROSS THE LOWER DESERTS OF AZ/SE CA
DURING THIS PERIOD...IT STILL APPEARS THAT WE WILL NOT SEE ANYTHING
CLOSE TO WHAT WE SAW EARLIER THIS WEEK...SINCE LATEST MODEL SUITES
ARE IN VERY STRONG AGREEMENT THAT ODILE WILL TRACK WELL OFF TO OUR
SOUTH AND WEST...EVENTUALLY DISSIPATING OVER THE COOLER WATERS OF
THE EASTERN PACIFIC...WELL OFF THE SOUTHERN CA COAST...WITH MOST OF
ITS ASSOCIATED MOISTURE REMAINING FAR AWAY FROM OUR REGION.
THUS...ONCE AGAIN GOING WITH THE DRIER EURO...WHICH KEEPS OUR PWATS
MAINLY AOB 1.50 INCH THROUGH THIS PERIOD.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...AND
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
NO AVIATION IMPACTS THROUGH FRIDAY MORNING...AS ONLY A FEW AFTERNOON
CU OVER TERRAIN FEATURES WILL PREVAIL ACROSS THE TERMINAL REGION.
SFC WINDS WILL REMAIN VERY LIGHT AOB 10 KT WITH MODERATE CONFIDENCE
OF WIND SHIFT TIMING. IN MANY LOCATIONS AFTER SUNSET...WINDS WILL BE
NEARLY CALM.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY.
INCREASING LOW TO MID LEVEL EASTERLY WINDS WILL DEVELOP OVER THE
WEEKEND...HELPING TO SPREAD MONSOONAL MOISTURE AND AN INCREASING
THREAT OF AFTERNOON AND EVENING THUNDERSTORMS BACK OVER THE REGION.
BY SUNDAY A SLIGHT CHANCE OF THUNDERSTORMS IS FORECAST ACROSS THE
ARIZONA DESERTS. HUMIDITY VALUES ACROSS THE DESERTS WILL BEGIN A
STEADY RISE OVER THE WEEKEND AND INTO NEXT WEEK WITH MINIMUM VALUES
FOR MOST AREAS CLIMBING ABOVE 20 PERCENT BY SUNDAY. OVERNIGHT
RECOVERY WILL BE GENERALLY GOOD THROUGH MONDAY WITH MAX HUMIDITY
VALUES CLIMBING ABOVE 50 PERCENT EACH NIGHT...BECOMING GOOD TO
EXCELLENT EARLY NEXT WEEK WITH MANY DESERT LOCALES EXCEEDING 70
PERCENT BY WEDNESDAY MORNING. THE BREEZY EAST WINDS SEEN OVER THE
WEEKEND WILL DIMINISH THROUGH THE MIDDLE OF NEXT WEEK...FAVORING THE
SOUTH TO SOUTHWEST DIRECTIONS AT GENERALLY LESS THAN 15 MPH.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
PREVIOUS DISCUSSION...PERCHA
AVIATION...MO
FIRE WEATHER...MCLANE/CB
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
1255 PM MST THU SEP 11 2014
...UPDATED AVIATION...
.SYNOPSIS...
THE COMBINATION OF A RATHER DRY AIRMASS AND HIGH PRESSURE ALOFT IS
EXPECTED TO KEEP SKIES MAINLY CLEAR OVER THE REGION THROUGH FRIDAY.
A VERY SLOW INCREASE IN MOISTURE WILL BEGIN LATE FRIDAY...THEN
CONTINUE INTO THE WEEKEND...AND INTO NEXT WEEK AS THE FLOW ALOFT
BECOMES MORE SOUTHEASTERLY. THIS WILL LEAD TO INCREASED CHANCES OF
SHOWERS AND THUNDERSTORMS...INITIALLY OVER MOUNTAINOUS AREAS OVER
THE WEEKEND...BUT POSSIBLY SPREADING INTO LOWER DESERT LOCATIONS BY
EARLY NEXT WEEK.
&&
.DISCUSSION...
LATEST RAP STREAMLINE ANALYSIS SHOWS A WEAK UPPER LEVEL TROUGH
SITUATED ACROSS AZ. SOMEWHAT DEEPER MOISTURE IS EVIDENT ON WV
IMAGERY EAST OF THE TROUGH ACROSS SOUTHERN AND EASTERN AZ...THOUGH
REGIONAL SOUNDINGS INDICATE PWATS ARE ONLY IN THE 1.0-1.2 INCH
RANGE. CONSENSUS OF CONVECTIVE ALLOWING MODELS SUGGESTS THAT
ISOLATED SHOWER AND THUNDERSTORM ACTIVITY WILL REMAIN CONFINED TO
THESE AREAS THIS AFTERNOON AND THIS IS REFLECTED IN THE CURRENT
FORECAST. ONLY MINOR ADJUSTMENTS TO THE SHORT-TERM TEMPERATURES AND
DEWPOINTS WERE NEEDED THIS MORNING.
&&
.PREVIOUS DISCUSSION...
TODAY THROUGH FRIDAY...
WESTERLY FLOW ALOFT OVER THE LAST 24-36 HOURS HAS NOW PUSHED ENOUGH
DRY AIR INTO THE REGION TO PUSH PWATS ACROSS MUCH OF OUR REGION TO
AOB 1.00 INCH. AS A RESULT...SKIES HAVE BECOME MOSTLY CLEAR WITH THE
MAIN MOISTURE PLUME NOW DISPLACED WELL TO OUR SOUTH AND
EAST...EXTENDING NORTHEASTWARD FROM NORTHERN MEXICO ACROSS SE NM
INTO W TX. NOT MUCH CHANGE IN THE SENSIBLE WEATHER IS EXPECTED
THROUGH FRIDAY AS WESTERLY FLOW CONTINUES OVER THE REGION. HIGH
TEMPERATURES ARE EXPECTED TO RISE TO NEAR 100 ACROSS THE LOWER
DESERTS TODAY...AND UP INTO THE 103-108F RANGE ON FRIDAY AS 700MB
TEMPS RISE FROM AROUND 11C TODAY TO AROUND 13 ON FRIDAY.
SATURDAY AND SUNDAY...
A SLOW INCREASE IN THE AVAILABLE MOISTURE LEVELS IS STILL EXPECTED
TO OCCUR OVER THE UPCOMING WEEKEND AS THE FLOW BELOW 400MB BECOMES
EASTERLY TO SOUTHEASTERLY...AND BEGINS TO PULL MOISTURE BACK INTO
THE REGION. THE GFS IS MOST BULLISH ON THIS MOISTURE
INCREASE...PUSHING PWATS UP TO NEAR 1.50 ON SATURDAY...WHILE THE
EURO KEEPS THEM MAINLY AOB 1.20 INCH. CONSIDERING THAT THE PRIMARY
REASON FOR THE INCREASE IN THE SFC PRESSURE GRADIENT/EASTERLY FLOW
IN THE LOW LEVELS IS THE FACT THAT A RATHER STRONG...AND QUITE COLD
SFC HIGH IS FORECAST TO DIVE SOUTHWARD INTO THE CENTRAL AND SOUTHERN
PLAINS...WITH ITS ORIGINS BEING FROM NORTHERN CANADA/ALASKA...RATHER
THAN A MORE TYPICAL SUBTROPICAL HIGH THAT OFTEN BUILDS OVER THAT
REGION THIS TIME OF YEAR...I AM INCLINED TO GO WITH THE DRIER EURO
FOR NOW. STILL...THERE SHOULD BE ENOUGH MOISTURE/INSTABILITY TO KEEP
SLIGHT CHANCES FOR SHOWERS/THUNDERSTORMS OVER THE HIGHER TERRAIN
NORTH AND EAST OF PHOENIX IN THE FORECAST...BUT WITH MAINLY SINGLE
DIGIT POPS OVER THE LOWER DESERTS. HIGH TEMPERATURES ARE EXPECTED TO
REMAIN MOSTLY IN THE 105-108F RANGE ACROSS SE CA AND SW AZ...BUT
COOL A DEGREE OR TWO OVER SOUTH-CENTRAL AZ AS A BIT OF COOLER AIR
WORKS ITS WAY IN FROM THE EAST.
MONDAY THROUGH WEDNESDAY...
A FURTHER MOISTURE INCREASE IS STILL EXPECTED DURING THIS TIME
PERIOD AS HURRICANE ODILE MOVES NORTHWESTWARD JUST OFF THE WEST
COAST OF BAJA CALIFORNIA. DEEP SE-LY FLOW TO THE EAST AND NORTHEAST
OF ODILE WILL LIKELY PUSH ADDITIONAL MOISTURE NORTHWESTWARD UP THE
GULF OF CALIFORNIA...AND INTO THE DESERT SOUTHWEST. ALTHOUGH THERE
WILL LIKELY BE ENOUGH INCREASE IN AVAILABLE MOISTURE TO TRIGGER AT
LEAST ISOLATED THUNDERSTORMS ACROSS THE LOWER DESERTS OF AZ/SE CA
DURING THIS PERIOD...IT STILL APPEARS THAT WE WILL NOT SEE ANYTHING
CLOSE TO WHAT WE SAW EARLIER THIS WEEK...SINCE LATEST MODEL SUITES
ARE IN VERY STRONG AGREEMENT THAT ODILE WILL TRACK WELL OFF TO OUR
SOUTH AND WEST...EVENTUALLY DISSIPATING OVER THE COOLER WATERS OF
THE EASTERN PACIFIC...WELL OFF THE SOUTHERN CA COAST...WITH MOST OF
ITS ASSOCIATED MOISTURE REMAINING FAR AWAY FROM OUR REGION.
THUS...ONCE AGAIN GOING WITH THE DRIER EURO...WHICH KEEPS OUR PWATS
MAINLY AOB 1.50 INCH THROUGH THIS PERIOD.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...AND
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
NO AVIATION IMPACTS THROUGH FRIDAY MORNING...AS ONLY A FEW AFTERNOON
CU OVER TERRAIN FEATURES WILL PREVAIL ACROSS THE TERMINAL REGION.
SFC WINDS WILL REMAIN VERY LIGHT AOB 10 KT WITH MODERATE CONFIDENCE
OF WIND SHIFT TIMING. IN MANY LOCATIONS AFTER SUNSET...WINDS WILL BE
NEARLY CALM.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY.
INCREASING LOW TO MID LEVEL EASTERLY WINDS WILL DEVELOP OVER THE
WEEKEND...HELPING TO SPREAD MONSOONAL MOISTURE AND AN INCREASING
THREAT OF AFTERNOON AND EVENING THUNDERSTORMS BACK OVER THE REGION.
BY SUNDAY A SLIGHT CHANCE OF THUNDERSTORMS IS FORECAST ACROSS THE
ARIZONA DESERTS. HUMIDITY VALUES ACROSS THE DESERTS WILL BEGIN A
STEADY RISE OVER THE WEEKEND AND INTO NEXT WEEK WITH MINIMUM VALUES
FOR MOST AREAS CLIMBING ABOVE 20 PERCENT BY SUNDAY. OVERNIGHT
RECOVERY WILL BE GENERALLY GOOD THROUGH MONDAY WITH MAX HUMIDITY
VALUES CLIMBING ABOVE 50 PERCENT EACH NIGHT...BECOMING GOOD TO
EXCELLENT EARLY NEXT WEEK WITH MANY DESERT LOCALES EXCEEDING 70
PERCENT BY WEDNESDAY MORNING. THE BREEZY EAST WINDS SEEN OVER THE
WEEKEND WILL DIMINISH THROUGH THE MIDDLE OF NEXT WEEK...FAVORING THE
SOUTH TO SOUTHWEST DIRECTIONS AT GENERALLY LESS THAN 15 MPH.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
PREVIOUS DISCUSSION...PERCHA
AVIATION...MO
FIRE WEATHER...MCLANE/CB
AREA FORECAST DISCUSSION
NWS TUCSON AZ
945 AM MST THU SEP 11 2014
.SYNOPSIS...A FEW SHOWERS AND THUNDERSTORMS WILL OCCUR THIS
AFTERNOON AND EVENING MAINLY NEAR THE NEW MEXICO BORDER. EXPECT
ISOLATED TO SCATTERED AFTERNOON AND EVENING THUNDERSTORMS ON FRIDAY
AND CONTINUING INTO NEXT WEEK AS MOISTURE GRADUALLY INCREASES.
WARMER DAYTIME TEMPERATURES WILL PREVAIL THROUGH FRIDAY FOLLOWED BY
MODEST COOLING EARLY THIS WEEKEND.
&&
.DISCUSSION...SUNNY SKIES ACROSS MUCH OF SE AZ AT THIS TIME WITH THE
EXCEPTION OF A FEW CIRRIFORM CLOUDS MAINLY SE OF TUCSON. DEWPOINTS
AT LOWER ELEVATIONS VALID 16Z WERE IN THE MID-UPPER 50S...AND THESE
TEMPS WERE NEARLY 2-5 DEGS F LOWER VERSUS 24 HOURS AGO. SURFACE
TEMPS VALID 16Z WERE ABOUT 2-5 DEGS F WARMER VERSUS THIS TIME WED.
11/12Z KTWC SOUNDING TOTAL PRECIP WATER WAS 1.05 INCHES...AND LIGHT
WLY/SWLY FLOW PREVAILED ABOVE 700 MB.
11/12Z NAM/GFS...11/12Z UNIV OF AZ WRF-NAM...AND THE 11/14Z RUC HRRR
WERE SIMILAR WITH DEPICTING A FEW SHOWERS/TSTMS TO OCCUR THIS
AFTERNOON AND THIS EVENING MAINLY NEAR THE NEW MEXICO BORDER. THE
WRF-NAM AND HRRR WERE ALSO SIMILAR WITH DEPICTING THE INITIAL
DEVELOPMENT OF SHOWERS/TSTMS TO OCCUR ON THE CHIRICAHUA MOUNTAINS
AROUND 18Z-19Z. THESE NWP MODELS DEPICT SHOWERS/TSTMS TO END BY
ABOUT 12/02Z-03Z...OR SHORTLY AFTER SUNSET. ANY RAINFALL AMOUNTS
WILL BE QUITE LIGHT THIS AFTERNOON AND EVENING. OTHERWISE...CLEAR
SKIES OR MOSTLY CLEAR SKIES INTO FRIDAY MORNING WEST OF TUCSON...
AND MOSTLY CLEAR SKIES TO PARTLY CLOUDY SKIES ELSEWHERE. HIGH TEMPS
THIS AFTERNOON WILL BE ABOUT 3-6 DEGS F WARMER ACROSS THE AREA
VERSUS WED.
THERE ARE NO UPDATES PLANNED AT THIS TIME. PLEASE REFER TO THE
ADDITIONAL SECTIONS FOR FURTHER DETAIL.
&&
.AVIATION...VALID THRU 12/12Z.
CLEAR SKIES WILL PREVAIL WEST OF KTUS THRU FRIDAY MORNING. KTUS
VICINITY EASTWARD EXPECT A FEW-SCT CLOUDS AT 8-12K FT AGL MAINLY
THIS AFTERNOON AND EVENING. THERE IS A SLIGHT CHANCE OF -SHRA/-TSRA
MAINLY NEAR THE NEW MEXICO BORDER THIS AFTERNOON AND THIS EVENING.
MOSTLY CLEAR SKIES SHOULD PREVAIL LATE TONIGHT INTO FRIDAY MORNING.
SURFACE WIND WILL GENERALLY BE LESS THAN 10 KTS. AVIATION DISCUSSION
NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...THERE IS A SLIGHT CHANCE OF SHOWERS AND
THUNDERSTORMS THIS AFTERNOON AND EVENING MAINLY NEAR THE NEW MEXICO
BORDER. ISOLATED TO SCATTERED AFTERNOON AND EVENING SHOWERS
AND THUNDERSTORMS WILL THEN RETURN STARTING FRIDAY AND CONTINUE INTO
NEXT WEEK AS MOISTURE GRADUALLY INCREASES ACROSS THE AREA. 20-FOOT
WINDS WILL GENERALLY BE LIGHT AND TERRAIN DRIVEN...EXCEPT FOR STRONG
GUSTY OUTFLOWS ASSOCIATED WITH THUNDERSTORMS.
&&
.PREV DISCUSSION...BY FRIDAY INCREASING WINDS TO OUR EAST OVER WEST
TEXAS AND SOUTHERN NEW MEXICO THAT ARE ASSOCIATED WITH THE BOUNDARY/
BACKDOOR FRONT WILL HELP TO USHER IN ADDITIONAL MOISTURE. AS A
RESULT OUR RAIN CHANCES WILL INCREASE...WITH ISOLATED SHOWER AND
THUNDERSTORM ACTIVITY FOR CENTRAL DESERTS...INCLUDING TUCSON AND
SCATTERED ACTIVITY OVER THE EASTERN ZONES BETWEEN TUCSON AND THE NEW
MEXICO BORDER.
FOR SATURDAY AND SUNDAY WE WILL STILL MAINTAIN GENERALLY ISOLATED
POPS FOR MOST AREAS WITH SCATTERED POPS FOR THE WHITE MOUNTAINS.
AS ANOTHER TROPICAL SYSTEM (ODILE)...HEADS TO THE NORTHWEST AND
EVENTUALLY ALONG THE WEST COAST OF THE BAJA PENINSULA...REACHING A
POSITION A COUPLE OF HUNDRED MILES WEST OF THE SOUTH CENTRAL BAJA
PENINSULA BY AROUND LATE MONDAY...WE SHOULD SEE SOME INFLUENCE WITH
AN INCREASE IN SHOWER AND THUNDERSTORM ACTIVITY AS MODELS ARE
SHOWING ACTIVITY DEVELOPING OVER NORTHERN MEXICO AND INTO PARTS OF
SOUTHERN ARIZONA. HOWEVER...THE WINDS IN THIS CASE WILL USHER
MOISTURE MOSTLY TO THE WEST OR WEST NORTHWEST...KEEPING THE BULK OF
THE SHOWERS AND THUNDERSTORMS TO OUR SOUTH. THAT SAID...JUST HAVE
CHANCE CATEGORY POPS ALONG THE INTERNATIONAL BORDER BEGINNING MONDAY
AND CONTINUING THROUGH THE MIDDLE OF NEXT WEEK. MORE NORTHERN PARTS
OF MY FORECAST AREA WILL STILL SEE SLIGHT CHANCE TYPE POPS FOR
DESERTS/VALLEYS AND CHANCE POPS FOR THE MOUNTAINS DURING THAT
PERIOD. OF COURSE THE FORECAST FOR NEXT WEEK WILL CONTINUALLY BE
REEVALUATED WITH EACH NEW MODEL RUN...SO STAY TUNED FOR CHANGES AND
ENHANCEMENTS TO THE FORECAST BETWEEN NOW AND EARLY NEXT WEEK.
HIGH TEMPERATURES WILL GENERALLY BE 1 TO 3 DEGS ABOVE NORMAL TODAY
AND ESPECIALLY FRIDAY...THEN NEAR OR SLIGHTLY BELOW NORMAL FOR
SATURDAY. THEREAFTER...HIGHS AT OR SLIGHTLY ABOVE NORMAL EACH DAY.
LOW TEMPS WILL BE SEVERAL DEGREES ABOVE NORMAL EACH MORNING.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
DISCUSSION...FRANCIS
PREVIOUS DISCUSSION...MOLLERE
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
930 AM MST THU SEP 11 2014
.SYNOPSIS...
THE COMBINATION OF A RATHER DRY AIRMASS AND HIGH PRESSURE ALOFT IS
EXPECTED TO KEEP SKIES MAINLY CLEAR OVER THE REGION THROUGH FRIDAY.
A VERY SLOW INCREASE IN MOISTURE WILL BEGIN LATE FRIDAY...THEN
CONTINUE INTO THE WEEKEND...AND INTO NEXT WEEK AS THE FLOW ALOFT
BECOMES MORE SOUTHEASTERLY. THIS WILL LEAD TO INCREASED CHANCES OF
SHOWERS AND THUNDERSTORMS...INITIALLY OVER MOUNTAINOUS AREAS OVER
THE WEEKEND...BUT POSSIBLY SPREADING INTO LOWER DESERT LOCATIONS BY
EARLY NEXT WEEK.
&&
.DISCUSSION...
LATEST RAP STREAMLINE ANALYSIS SHOWS A WEAK UPPER LEVEL TROUGH
SITUATED ACROSS AZ. SOMEWHAT DEEPER MOISTURE IS EVIDENT ON WV
IMAGERY EAST OF THE TROUGH ACROSS SOUTHERN AND EASTERN AZ...THOUGH
REGIONAL SOUNDINGS INDICATE PWATS ARE ONLY IN THE 1.0-1.2 INCH
RANGE. CONSENSUS OF CONVECTIVE ALLOWING MODELS SUGGESTS THAT
ISOLATED SHOWER AND THUNDERSTORM ACTIVITY WILL REMAIN CONFINED TO
THESE AREAS THIS AFTERNOON AND THIS IS REFLECTED IN THE CURRENT
FORECAST. ONLY MINOR ADJUSTMENTS TO THE SHORT-TERM TEMPERATURES AND
DEWPOINTS WERE NEEDED THIS MORNING.
&&
.PREVIOUS DISCUSSION...
TODAY THROUGH FRIDAY...
WESTERLY FLOW ALOFT OVER THE LAST 24-36 HOURS HAS NOW PUSHED ENOUGH
DRY AIR INTO THE REGION TO PUSH PWATS ACROSS MUCH OF OUR REGION TO
AOB 1.00 INCH. AS A RESULT...SKIES HAVE BECOME MOSTLY CLEAR WITH THE
MAIN MOISTURE PLUME NOW DISPLACED WELL TO OUR SOUTH AND
EAST...EXTENDING NORTHEASTWARD FROM NORTHERN MEXICO ACROSS SE NM
INTO W TX. NOT MUCH CHANGE IN THE SENSIBLE WEATHER IS EXPECTED
THROUGH FRIDAY AS WESTERLY FLOW CONTINUES OVER THE REGION. HIGH
TEMPERATURES ARE EXPECTED TO RISE TO NEAR 100 ACROSS THE LOWER
DESERTS TODAY...AND UP INTO THE 103-108F RANGE ON FRIDAY AS 700MB
TEMPS RISE FROM AROUND 11C TODAY TO AROUND 13 ON FRIDAY.
SATURDAY AND SUNDAY...
A SLOW INCREASE IN THE AVAILABLE MOISTURE LEVELS IS STILL EXPECTED
TO OCCUR OVER THE UPCOMING WEEKEND AS THE FLOW BELOW 400MB BECOMES
EASTERLY TO SOUTHEASTERLY...AND BEGINS TO PULL MOISTURE BACK INTO
THE REGION. THE GFS IS MOST BULLISH ON THIS MOISTURE
INCREASE...PUSHING PWATS UP TO NEAR 1.50 ON SATURDAY...WHILE THE
EURO KEEPS THEM MAINLY AOB 1.20 INCH. CONSIDERING THAT THE PRIMARY
REASON FOR THE INCREASE IN THE SFC PRESSURE GRADIENT/EASTERLY FLOW
IN THE LOW LEVELS IS THE FACT THAT A RATHER STRONG...AND QUITE COLD
SFC HIGH IS FORECAST TO DIVE SOUTHWARD INTO THE CENTRAL AND SOUTHERN
PLAINS...WITH ITS ORIGINS BEING FROM NORTHERN CANADA/ALASKA...RATHER
THAN A MORE TYPICAL SUBTROPICAL HIGH THAT OFTEN BUILDS OVER THAT
REGION THIS TIME OF YEAR...I AM INCLINED TO GO WITH THE DRIER EURO
FOR NOW. STILL...THERE SHOULD BE ENOUGH MOISTURE/INSTABILITY TO KEEP
SLIGHT CHANCES FOR SHOWERS/THUNDERSTORMS OVER THE HIGHER TERRAIN
NORTH AND EAST OF PHOENIX IN THE FORECAST...BUT WITH MAINLY SINGLE
DIGIT POPS OVER THE LOWER DESERTS. HIGH TEMPERATURES ARE EXPECTED TO
REMAIN MOSTLY IN THE 105-108F RANGE ACROSS SE CA AND SW AZ...BUT
COOL A DEGREE OR TWO OVER SOUTH-CENTRAL AZ AS A BIT OF COOLER AIR
WORKS ITS WAY IN FROM THE EAST.
MONDAY THROUGH WEDNESDAY...
A FURTHER MOISTURE INCREASE IS STILL EXPECTED DURING THIS TIME
PERIOD AS HURRICANE ODILE MOVES NORTHWESTWARD JUST OFF THE WEST
COAST OF BAJA CALIFORNIA. DEEP SE-LY FLOW TO THE EAST AND NORTHEAST
OF ODILE WILL LIKELY PUSH ADDITIONAL MOISTURE NORTHWESTWARD UP THE
GULF OF CALIFORNIA...AND INTO THE DESERT SOUTHWEST. ALTHOUGH THERE
WILL LIKELY BE ENOUGH INCREASE IN AVAILABLE MOISTURE TO TRIGGER AT
LEAST ISOLATED THUNDERSTORMS ACROSS THE LOWER DESERTS OF AZ/SE CA
DURING THIS PERIOD...IT STILL APPEARS THAT WE WILL NOT SEE ANYTHING
CLOSE TO WHAT WE SAW EARLIER THIS WEEK...SINCE LATEST MODEL SUITES
ARE IN VERY STRONG AGREEMENT THAT ODILE WILL TRACK WELL OFF TO OUR
SOUTH AND WEST...EVENTUALLY DISSIPATING OVER THE COOLER WATERS OF
THE EASTERN PACIFIC...WELL OFF THE SOUTHERN CA COAST...WITH MOST OF
ITS ASSOCIATED MOISTURE REMAINING FAR AWAY FROM OUR REGION.
THUS...ONCE AGAIN GOING WITH THE DRIER EURO...WHICH KEEPS OUR PWATS
MAINLY AOB 1.50 INCH THROUGH THIS PERIOD.
&&
AVIATION...
SOUTH-CENTRAL ARIZONA...SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA
INCLUDING KPHX...KIWA...KSDL...KIPL...AND KBLH...
HIGH PRESSURE ALOFT CONTINUES TO BUILD ACROSS THE LOWER DESERTS...AS
AS THIS OCCURS DRIER AIR WILL FILTER IN FROM THE WEST. AS
SUCH...EXPECT GENERALLY CLEAR SKIES NEXT 24 HOURS WITH POSSIBLY A
FEW CU DECKS DURING THE AFTERNOON HOURS AT THE TAF SITES...WITH
BASES AOA 6K FEET. OTHERWISE...WINDS TO BE QUITE LIGHT AND VARIABLE
AT THE TERMINALS...OCCASIONALLY FOLLOWING NORMAL DIURNAL DIRECTIONS.
NO AVIATION IMPACTS EXPECTED NEXT 24 HOURS WITH VFR CONDITIONS AT
ALL TERMINALS THROUGH FRIDAY MORNING.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY.
INCREASING LOW TO MID LEVEL EASTERLY WINDS WILL DEVELOP OVER THE
WEEKEND...HELPING TO SPREAD MONSOONAL MOISTURE AND AN INCREASING
THREAT OF AFTERNOON AND EVENING THUNDERSTORMS BACK OVER THE REGION.
BY SUNDAY A SLIGHT CHANCE OF THUNDERSTORMS IS FORECAST ACROSS THE
ARIZONA DESERTS. HUMIDITY VALUES ACROSS THE DESERTS WILL BEGIN A
STEADY RISE OVER THE WEEKEND AND INTO NEXT WEEK WITH MINIMUM VALUES
FOR MOST AREAS CLIMBING ABOVE 20 PERCENT BY SUNDAY. OVERNIGHT
RECOVERY WILL BE GENERALLY GOOD THROUGH MONDAY WITH MAX HUMIDITY
VALUES CLIMBING ABOVE 50 PERCENT EACH NIGHT...BECOMING GOOD TO
EXCELLENT EARLY NEXT WEEK WITH MANY DESERT LOCALES EXCEEDING 70
PERCENT BY WEDNESDAY MORNING. THE BREEZY EAST WINDS SEEN OVER THE
WEEKEND WILL DIMINISH THROUGH THE MIDDLE OF NEXT WEEK...FAVORING THE
SOUTH TO SOUTHWEST DIRECTIONS AT GENERALLY LESS THAN 15 MPH.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
PREVIOUS DISCUSSION...PERCHA
AVIATION...CB
FIRE WEATHER...MCLANE/CB
AREA FORECAST DISCUSSION
NWS MIAMI FL
200 PM EDT THU SEP 11 2014
.AVIATION...
LARGE SHIELD OF MODERATE TO HEAVY RAINFALL ASSOCIATED WITH MID
LEVEL CIRCULATION JUST WEST OF THE BAHAMAS HAS REMAINED OFFSHORE
THUS FAR THIS AFTERNOON. HOWEVER...CONVECTIVE BANDS EMANATING FROM
THIS CIRCULATION CONTINUE TO PUSH INTO PALM BEACH COUNTY. LATEST
HRRR AND OTHER HI-RES MODELS SEEM TO BE RETRACTING THEIR DEPICTION
OF OVERALL COVERAGE OF HEAVY RAIN...BUT STILL SHOW A RATHER LARGE
AREA OF SHOWERS PUSHING ACROSS THE EAST COAST SITES THROUGH 00Z AS
THE CIRCULATION CENTER SLOWLY SLIDES TO THE WEST. THEREFORE PLACED
TEMPOS IN AT ALL EAST COAST SITES FOR SHOWERS AND MVFR CIGS
THROUGH 00Z. ISOLATED IFR CIGS/VSBYS ARE POSSIBLE WITHIN THE
HEAVIEST SHOWERS BUT SHOULD BE BRIEF AND LEFT OUT OF TAFS FOR NOW.
WINDS SHOULD BE LIGHT OVERNIGHT AND INTO THE MORNING HOURS
TOMORROW BEFORE BECOMING ESE AGAIN TOMORROW AFTERNOON WITH THE
CIRCULATION CENTER TO THE WEST OF THE EAST COAST SITES.
&&
.PREV DISCUSSION... /ISSUED 1049 AM EDT THU SEP 11 2014/
UPDATE...
ONLY SIGNIFICANT CHANGE TO THE FORECAST IS TO REDUCE POPS THIS
MORNING AS THERE HAS BEEN SOME WEAK SUBSIDENCE AHEAD OF THE WEAK
LOW OVER THE BAHAMAS. THE HRRR IS SHOWING THAT MOST CONVECTIVE
DEVELOPMENT OVER THE MAINLAND WILL HOLD OFF UNTIL AFTER 18Z. EVEN
THEN, MOST OF IT IS INDICATED TO BE OVER THE INTERIOR THIS
AFTERNOON. THE MODEL DOES THEN BRING SHOWERS AND THUNDERSTORMS TO
THE EASTERN COASTAL AREAS OF SOUTH FLORIDA THIS EVENING. THE ONLY
THREAT OF CONCERN RIGHT NOW IS A LOW CHANCE OF URBAN FLOODING DUE
TO SLOW MOVING HEAVY SHOWERS AND THUNDERSTORMS.
PREV DISCUSSION... /ISSUED 450 AM EDT THU SEP 11 2014/
DISCUSSION...
AN AREA OF LOW PRESSURE NEAR THE NORTHWEST BAHAMAS WILL DOMINATE
THE WEATHER DISCUSSION OVER THE NEXT COUPLE DAYS. MODELS ARE IN
GOOD AGREEMENT THAT THIS WEAK SYSTEM WILL MOVE SLOWLY WESTWARD
ACROSS THE NORTHWEST BAHAMAS AND THEN ACROSS SOUTH FLORIDA ON
FRIDAY. CONDITIONS ARE FORECAST TO BECOME UNFAVORABLE OVER THE LOW
TODAY AS SHEAR INCREASES. HOWEVER...THERE IS STILL A SLIGHT CHANCE
THAT THE SYSTEM MAY DEVELOP BEFORE MOVING INTO SOUTH FLORIDA...AND
THEN A MEDIUM CHANCE AFTER IT MOVES INTO THE GULF OF MEXICO OVER
THE WEEKEND. REGARDLESS OF DEVELOPMENT...THE MAIN IMPACT FOR
SOUTH FLORIDA WILL LIKELY BE LOCALLY HEAVY RAINFALL.
TODAY...THE WIND FIELD OVER/NEAR THE LOW IS LIGHT...AND WINDS ARE
FORECAST TO BE VERY LIGHT ACROSS THE REGION TODAY. A LIGHT
NORTHEASTERLY FLOW MAY BRIEFLY DEVELOP BEFORE SEA BREEZE
BOUNDARIES BECOME DOMINANT. STORM MOTION IS FORECAST TO BE
RELATIVELY SLOW TODAY...AND LOCALLY HEAVY RAINFALL IS POSSIBLE.
PONDING IN POORLY DRAINED AREAS AND LOCALIZED STREET FLOODING ARE
THE MAIN THREATS. RAIN CHANCES ARE 50-70% ACROSS THE
REGION. THE LATEST HRRR RUN SHOWS PRETTY HIGH COVERAGE OF RAIN
ACROSS THE REGION. HIGHS ARE FORECAST TO BE IN THE UPPER 80S TO
AROUND 90 DEGREES.
TONIGHT...THE WEAK AREA OF LOW PRESSURE WILL MOVE CLOSER TO THE
EAST COAST...IN THE VICINITY OF PALM BEACH COUNTY COAST BY
DAYBREAK. SCATTERED SHOWERS AND A FEW EMBEDDED STORMS ARE
FORECAST FOR THE EAST COAST METRO AREAS OVERNIGHT.
FRIDAY...THE AREA OF LOW PRESSURE IS FORECAST TO MOVE SLOWLY
ACROSS THE REGION...AND SHOWERS AND STORMS ARE LIKELY THROUGHOUT
THE DAY. LOCALLY HEAVY RAIN AND MINOR STREET FLOODING IS POSSIBLE.
CLOUD COVER AND RAINFALL IS FORECAST TO KEEP TEMPS IN THE 80S. THE
AREA OF LOW PRESSURE IS FORECAST TO MOVE SOUTHWEST INTO THE GULF
OF MEXICO FRIDAY NIGHT...AND RAIN CHANCES WILL CONTINUE ACROSS
COASTAL AREAS.
SATURDAY AND SUNDAY...DEEP MOISTURE WILL REMAIN ACROSS SOUTH
FLORIDA THROUGH THE WEEKEND. THE ECMWF KEEPS A TROUGH AXIS
LINGERING OVER THE REGION EXTENDING TO THE EAST OF THE AREA OF LOW
PRESSURE THROUGH SUNDAY. THE GFS MOVES THE SYSTEM QUICKLY
WESTWARD ACROSS THE GULF...WITH A RETURN OF THE DEEP EAST TO
SOUTHEAST FLOW OBSERVED OVER THE PAST SEVERAL DAYS ON SUNDAY AS
THE RIDGE BUILDS WESTWARD ACROSS THE REGION. SO RAIN CHANCES WILL
REMAIN IN THE LIKELY CATEGORY ON SATURDAY...AND THEN COME DOWN A
LITTLE ON SUNDAY.
HIGH PRESSURE WILL THEN BUILD ACROSS THE REGION EARLY NEXT
WEEK...WITH A MORE TYPICAL EASTERLY FLOW RAINY SEASON PATTERN.
MARINE...
A WEAK AREA OF LOW PRESSURE NEAR THE NORTHERN BAHAMAS IS FORECAST
TO PUSH SLOWLY WEST ACROSS THE LOCAL ATLANTIC WATERS TONIGHT AND
THEN INTO THE GULF WATERS FRIDAY NIGHT. THE NHC IS MONITORING
THIS DISTURBANCE...AND THIS COULD IMPACT THE FORECAST FOR FRIDAY
AND INTO THE WEEKEND. LIGHT WINDS ARE FORECAST TODAY...WITH
GENERALLY EAST TO SOUTHEAST WINDS FRIDAY THROUGH THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 75 86 76 87 / 40 60 20 60
FORT LAUDERDALE 76 88 77 88 / 40 60 30 70
MIAMI 75 86 77 88 / 30 70 30 60
NAPLES 74 89 75 90 / 30 60 30 70
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
154 PM EDT THU SEP 11 2014
.PREV DISCUSSION...
UPDATE...
/ISSUED 1122 AM EDT THU SEP 11 2014/
ALREADY SHOWERS ACROSS FAR NORTH GEORGIA. BOTH HRRR AND LOCAL WRF
INCREASE DEVELOPMENT INTO THE AFTERNOON HOWEVER TWO OTHER HI RES
MODELS ARE MUCH MORE CONSERVATIVE IN TERMS OF PRECIPITATION.
CONSIDERING THE TRENDS OF THE HRRR THIS SUMMER...IT MAY BE
SLIGHTLY OVERDONE. UPDATED POPS THIS MORNING LEAN TOWARDS THE
BETTER CHANCES OF PRECIPITATION...GIVEN APPROACHING FRONTAL
BOUNDARY...BUT DO NOT SHOW BETTER PRECIP CHANCES AS FAR SOUTH AS
THE HRRR AND THE LOCAL WRF. WILL HAVE TO CONTINUE TO MONITOR THE
PRECIP TRENDS THOUGH FOR FUTURE UPDATES.
11
SHORT TERM /TODAY THROUGH FRIDAY/...
/ISSUED AT 456 AM EDT THU SEP 11 2014/
MODELS IN CLOSE AGREEMENT THROUGH THE LONG TERM. SURFACE FRONT AND
ASSOCIATED SHORT WAVE WILL MOVE INTO THE TENNESSEE VALLEY TODAY AND
THIS WILL INCREASE THE RISK OF SHOWERS AND TSTORMS OVER NORTH GA
THIS AFTERNOON. ALTHOUGH SHEAR IS NOT IMPRESSIVE...SBCAPES ARE
RUNNING IN THE 1500 TO 2500 DEPENDING ON THE MODEL WHICH COULD
BE ENOUGH TO PRODUCE STRONG STORMS WITH GUSTY WINDS. THE
INHIBITING FACTOR TO STRONG STORMS WILL BE THE H5 HIGH SITTING
OVER THE GA/AL BORDER NEAR CSG. PROXIMITY TO THIS COULD KEEP
TSTORMS FROM GOING SEVERE...HOWEVER THIS WILL NEED TO BE WATCHED. A
DIFFERENT STORY ON FRIDAY AS THE H5 HIGH WEAKENS AND THE SURFACE
FRONT DROPS INTO THE STATE. CONVERGENCE ALONG THE FRONT AS WELL AS
CAPES IN THE 2000 TO 2500 RANGE BY ALL MODELS WILL BE ENOUGH FOR A
FEW STRONG TO SEVERE STORMS TO DEVELOP DURING FRIDAY
AFTERNOON...MAINLY ACROSS NORTH GEORGIA.
17
LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
/ISSUED AT 456 AM EDT THU SEP 11 2014/
EXTENDED MODELS CONSISTENT WITH SHOWING AFOREMENTIONED SHORT-TERM
FRONT STALLED ACROSS THE STATE SATURDAY AS A SECONDARY FRONT
APPROACHES THE AREA. UPPER LOW TRACKING ACROSS THE SOUTHERN GREAT
LAKES WILL PULL THE SECOND FRONT INTO THE REGION QUICKLY BEHIND
THE FIRST...WITH AMPLE MOISTURE POSITIONED ACROSS THE STATE
SATURDAY THROUGH EARLY NEXT WEEK AS BOUNDARIES BECOME STATIONARY
AND PILE UP ACROSS CENTRAL GEORGIA. THESE FRONTS WILL SERVE AS A
FOCUS FOR ENHANCED SHOWERS AND THUNDERSTORMS ACROSS THE STATE. NOT
UNTIL A SHORTWAVE SWEEPS INTO THE REGION TUESDAY AND KICKS THE
STATIONARY FRONTS EASTWARD DOES THE STATE REALLY GET TO SEE SOME
DRIER AIR MOVE INTO THE STATE.
FOR NOW...HAVE OPTED TO CONTINUE WITH GOOD CHANCE TO LIKELY POPS
ACROSS A VAST MAJORITY OF THE AREA SATURDAY THROUGH MONDAY. INTO
MID WEEK NEXT WEEK THE EXTENDED MODELS DISAGREE WITH THE EXTENT
THE DRIER AIR PUSHES INTO THE STATE AND WITH A SERIES OF UPPER
LEVEL DISTURBANCES THROUGH THE AREA. AS A RESULT...ASIDE FROM ZERO
POPS IN FAR NW GEORGIA ON SUNDAY NIGHT AND TUESDAY NIGHT...CARRY
AT LEAST GOOD CHANCE POPS ACROSS THE STATE EACH AFTERNOON...AND
AT LEAST SLIGHT CHANCE EACH OVERNIGHT.
MODELS ARE INDICATING THAT COOLER TEMPERATURES ARE IN STORE FOR
THE STATE BY THE WEEKEND...ESPECIALLY WITH THE INFLUENCE OF THE
PRECIPITATION AND CLOUDS. ANTICIPATE AN OVERALL COOLING TREND
THROUGH THE WEEK...AND BY THE LATTER HALF OF NEXT WEEK COULD BE
BELOW NORMAL FOR TEMPERATURES.
AS OF NOW...WEEKEND QPF IS EXPECTED TO BE 0.75 TO 1.5
INCHES...WITH THE HIGHEST AMOUNTS GENERALLY NOSING INTO THE STATE
FROM THE CAROLINAS. LOCALLY HEAVIER AMOUNTS CAN BE EXPECTED. AT
THIS TIME...GUIDANCE SUGGESTS MUCH OF THE STATE CAN HANDLE THIS
AMOUNT OF RAINFALL AND WILL NOT ISSUE ANY KIND OF WATCH AT THIS TIME.
31
&&
.AVIATION...
18Z UPDATE...
A BIT OF UNCERTAINTY IN TERMS OF SHRA/TSRA POTENTIAL AT NORTHERN
SITES. THINK SOME DEVELOPMENT WILL DRIFT INTO THE ATL SITES AT
SOME POINT. ADVERTISING TSRA IN THE TAFS SINCE THERE IS SOME
INSTABILITY...BUT BASED ON CURRENT RADAR TRENDS...COULD END UP
BEING JUST SHRA. CHANCES DECREASE INTO AHN AND THEN EVEN MORE INTO
MCN AND CSG.
//ATL CONFIDENCE...18Z UPDATE...
HIGH CONFIDENCE ON WIND. MEDIUM CONFIDENCE ON CIGS AND VSBYS.
11
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 90 71 90 70 / 30 30 60 60
ATLANTA 88 72 89 72 / 40 30 50 50
BLAIRSVILLE 82 67 81 65 / 60 50 60 60
CARTERSVILLE 88 71 89 69 / 50 40 50 50
COLUMBUS 91 73 93 72 / 20 20 50 50
GAINESVILLE 85 71 87 69 / 40 30 60 60
MACON 92 71 93 71 / 20 10 50 50
ROME 89 70 89 69 / 50 50 60 50
PEACHTREE CITY 89 70 90 69 / 30 20 50 50
VIDALIA 92 72 93 72 / 20 10 40 40
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...11
LONG TERM....BAKER
AVIATION...11
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
302 PM CDT THU SEP 11 2014
.DISCUSSION...
240 PM...FORECAST CONCERNS INCLUDE MUCH BELOW NORMAL TEMPERATURES
AND CHANCES FOR SHOWERS THROUGH SATURDAY AND AGAIN ON MONDAY.
STRATUS DECK HAS REMAINED MOSTLY OVERCAST TODAY AND THAT HAS HELD
TEMPS IN THE LOWER/MID 50S MOST AREAS...SOME 20 TO 25 DEGREES
BELOW NORMAL FOR MID SEPTEMBER. SEE CLIMATE SECTION BELOW FOR
RECORDS. CLOUD COVER IS EXPECTED TO REMAIN AT LEAST BROKEN IF NOT
OVERCAST OVERNIGHT INTO FRIDAY MORNING...SO NOT EXPECTING MUCH OF
A SWING IN TEMPS WITH LOWS TONIGHT IN THE MID/UPPER 40S.
AS COLDER AIR CONTINUES TO SPREAD ACROSS THE AREA...A FEW LAKE
EFFECT RAIN SHOWERS HAVE DEVELOPED OVER THE SOUTHEASTERN PART OF
THE LAKE. AS HIGH PRESSURE MOVES NORTH OF THE AREA TONIGHT...
WINDS WILL TURN MORE NORTHEAST AND THESE LAKE EFFECT RAIN SHOWERS
WILL BEGIN TO AFFECT NORTHEAST IL OVERNIGHT INTO FRIDAY MORNING.
COVERAGE REMAINS A BIT UNCERTAIN AND HAVE ONLY BUMPED POPS UP TO
LOW CHANCE. TRENDS WILL NEED TO BE MONITORED LATER TONIGHT WITH
THE POSSIBILITY THAT POPS WILL NEED TO BE BUMPED UP FURTHER.
LAKE EFFECT RAIN SHOWERS WILL CONTINUE INLAND ACROSS NORTHERN IL
FRIDAY MORNING AS FLOW TURNS MORE EAST/NORTHEAST. CLOUD COVER WILL
LIKELY REMAIN MOSTLY CLOUDY AND THIS COULD LIMIT TEMPS TO JUST THE
50S AGAIN ON FRIDAY. SOUTHERN AREAS MAY SEE A FEW BREAKS WITH THE
POTENTIAL TO REACH 60...BUT OVERALL FRIDAY WILL CONTINUE MUCH
BELOW NORMAL.
AN UPPER WAVE WILL MOVE ACROSS THE REGION FRIDAY AFTERNOON INTO
FRIDAY EVENING WITH SHOWERS/LIGHT RAIN SPREADING ACROSS THE
NORTHWEST CWA IN THE AFTERNOON THEN ACROSS MUCH OF THE AREA EARLY
FRIDAY EVENING. BUMPED POPS UP SOME...WITH LIKELY OVER THE
NORTHERN TWO THIRDS OF THE CWA...POSSIBLE POPS WILL NEED TO BE
INCREASED HERE AS WELL...THOUGH TOTAL QFP AMOUNTS SHOULD BE IN THE
0.25 TO 0.5 INCH RANGE. THIS WAVE IS FAIRLY PROGRESSIVE...SO
TRIMMED POPS FROM THE WEST OVERNIGHT. LAKE EFFECT RAIN SHOWERS MAY
CONTINUE INTO NORTHWEST INDIANA SATURDAY MORNING BEFORE ENDING IN
THE AFTERNOON.
DESPITE SOME SUNSHINE SATURDAY...AIRMASS WILL BE EVEN COLDER THAN
TODAY AND FRIDAY. NOT SURE HOW MUCH MID SEPTEMBER SUN WILL AID
TEMP INCREASE SO MAINTAINED JUST LOWER 60S FOR HIGHS. HIGH
PRESSURE PASSES ACROSS THE REGION SATURDAY NIGHT INTO SUNDAY
MORNING WITH LOWS DIPPING INTO THE LOWER 40S MOST AREAS...BUT
WARMER IN THE IMMEDIATE CHICAGO METRO AREA.
ANOTHER FAST MOVING WAVE WILL MOVE ACROSS THE AREA MONDAY
BRINGING ANOTHER CHANCE OF SHOWERS. DEPENDING ON TIMING...CLOUD
COVER AND PRECIP COULD HOLD TEMPS DOWN MONDAY BUT FOR NOW HAVE
MAINTAINED 60S. BEYOND MONDAY...HIGH PRESSURE SPREADS ACROSS THE
REGION WITH DRY WEATHER EXPECTED MID WEEK BUT TEMPS STILL BELOW
NORMAL. CMS
&&
.CLIMATE...
915 AM CDT SEP 11 2014
AN UNSEASONABLY COOL AIR MASS OVER THE REGION INTO THE WEEKEND
COULD PUT SOME RECORD TEMPERATURES IN JEOPARDY AT CHICAGO AND
ROCKFORD. RECORD LOW MAX TEMPERATURES ARE MOST LIKELY TO BE
THREATENED.
RECORD LOW MAX TEMPERATURES SEPTEMBER 11-13
-------------------------------------------
SEPTEMBER 11 SEPTEMBER 12 SEPTEMBER 13
------------ ------------ ------------
CHICAGO 61/1940 53/1902 55/1880
ROCKFORD 55/1914 56/1943 55/1970
RC
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* MVFR CIGS THROUGH THE PERIOD...WITH POTENTIAL FOR IFR LATE
TONIGHT INTO FRIDAY MORNING.
* NORTH-NORTHEAST WINDS 360-030 DEG AT OR BELOW 10 KT INTO THIS
EVENING.
* LAKE EFFECT SHOWERS LATE TONIGHT INTO FRIDAY MORNING.
* NORTH-NORTHEAST WINDS AROUND 10 KT BECOMING NORTHEAST ON FRIDAY.
* RAIN SHOWERS MOVING INTO AREA LATE FRIDAY AFTERNOON...WITH
PREVAILING RAIN AND CIG/VSBY IMPACTS MORE LIKELY FRIDAY EVE.
RC
//DISCUSSION...UPDATED 18Z...
UNSEASONABLY COOL AIR MASS OVER THE REGION IS RESULTING IN SEVERAL
CONCERNS THIS PERIOD. MOISTURE LOCKED UNDER INVERSION IS KEEPING
STRATUS DECK IN PLACE THIS AFTERNOON AND NOW EXPECT PRIMARILY MVFR
CIGS THROUGH THE PERIOD. THE COOL AIR MASS MOVING OVER THE MILD
LAKE WATERS WILL LIKELY RESULT IN THE DEVELOPMENT OF LAKE EFFECT
SHOWERS LATE TONIGHT INTO FRIDAY MORNING. HIGHER RESOLUTION
GUIDANCE HINTS THAT DECENT BAND COULD EVEN SET UP INTO NORTHWEST
INDIANA INITIALLY AND THEN GRADUALLY SHIFT NORTHEAST. HAVE MEDIUM
TO HIGH CONFIDENCE THAT THERE WILL BE SHOWERS AROUND...BUT LOW
CONFIDENCE IN DIRECT IMPACTS TO ORD/MDW/GYY...THUS HAVE CARRIED
VCSH MENTION. IF SHRA ARE MORE ORGANIZED AND DIRECTLY IMPACT
TERMINALS...THERE COULD BE IMPACTS TO VSBY.
ONSHORE FLOW IS EXPECTED TO ALSO RESULT IN LOWERING OF MVFR
CIGS AT EASTERN TERMINALS...WITH SOME GUIDANCE MEMBERS INDICATING
POTENTIAL FOR IFR. HAVE HINTED AT THIS WITH SCT IFR CLOUDS IN TAF.
A FAIRLY STRONG UPPER LEVEL DISTURBANCE AND REINFORCING SHOT OF
COOL AIR WILL MOVE ACROSS REGION DURING THE DAY ON FRIDAY...AND
THIS WILL RESULT IN RAIN SHOWERS SPREADING IN FROM NORTHWEST.
PREVAILING RAIN SHOWERS ARE EXPECTED IN ROCKFORD VICINITY DURING
AFTERNOON...BUT NOT UNTIL BEYOND THE 30 HOUR ORD TAF AT THE
EASTERN TAF SITES.
REGARDING WINDS...PREDOMINANTLY NORTHERLY WINDS EARLY THIS
AFTERNOON ARE EXPECTED TO SHIFT TO NORTHEAST OR NORTH-NORTHEAST
LATER THIS AFTERNOON INTO THE EVENING. IF AN ORGANIZED LAKE EFFECT
BAND SETS UP INTO NORTHEAST ILLINOIS OVERNIGHT...WINDS MAY TREND
MORE NORTHERLY OR EVEN NORTH-NORTHWEST...BUT THEN NORTHEAST WINDS
AROUND 10 KT ARE EXPECTED FRIDAY MORNING THROUGH THE END OF THE
PERIOD.
RC
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM-HIGH IN MVFR CIGS CONTINUING THROUGH THE PERIOD. LOW IN
IFR LATE TONIGHT INTO FRIDAY.
* MEDIUM IN WIND TRENDS THROUGH THE PERIOD. MEDIUM IN WIND SPEEDS
INTO THIS EVENING.
* MEDIUM-HIGH IN LAKE EFFECT SHOWERS DEVELOPING TONIGHT...LOW IN
DIRECT IMPACTS TO TERMINALS.
* MEDIUM IN PREVAILING RAIN SHOWERS MORE LIKELY TO MOVE IN FRIDAY
EVENING.
RC
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...SHRA LIKELY. MVFR/IFR CIGS PSBL.
SATURDAY...VFR. GUSTY NW WINDS IN THE MORNING.
SUNDAY...VFR.
MONDAY...CHC SHRA DURING THE DAY. MVFR CIGS PSBL.
TUESDAY AND WEDNESDAY...VFR
KMD
&&
.MARINE...
209 PM CDT
STRONG LOW PRESSURE SYSTEM THAT BROUGHT THE GALE FORCE WINDS HAS
CONTINUED TO LIFT NORTHEAST AWAY FROM THE GREAT LAKES REGION...WITH
THE GRADIENT OVER LAKE MICHIGAN STEADILY WEAKENING. THE GRADIENT
WILL REMAIN JUST ENOUGH TO PRODUCE WINDS BETWEEN 15 AND 25 KT
OVERNIGHT GENERALLY FROM THE NORTH...BEGINNING TO TURN SLIGHTLY
NORTHEAST AHEAD OF THE BROAD RIDGE OF HIGH PRESSURE OVER THE CENTRAL
PLAINS THAT IS POISED TO ARRIVE SATURDAY INTO SUNDAY MORNING.
ANOTHER FRONTAL BOUNDARY WILL ARRIVE FRIDAY EVENING WHICH WILL
PROVIDE A REINFORCING PUSH OF GUSTY NORTH WINDS TO THE LAKE...WITH
THE GRADIENT BEING SLIGHTLY TIGHTER ALONG THE SOUTHERN HALF OF THE
LAKE FRIDAY NIGHT THROUGH EARLY SATURDAY. WAVES WILL REMAIN ELEVATED
THROUGH FRIDAY NIGHT...CREATING HAZARDOUS WAVES TO SMALL CRAFT
THROUGH THIS PERIOD. THEN THE WAVES SHOULD STEADILY DIMINISH BY
EARLY SATURDAY MORNING TO ALLOW THE SMALL CRAFT TO END. HOWEVER IF
THE WINDS REMAIN ELEVATED...THIS WILL KEEP WAVES UP AS WELL THROUGH
DAYBREAK SAT. HIGH PRESSURE IS THEN POISED TO BUILD OVER LAKE
MICHIGAN SATURDAY EVENING AND CONTINUE THROUGH SUNDAY. WHICH WILL
THEN PROVIDE MUCH LIGHTER WINDS AND SUBSIDING WAVES.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...BEACH HAZARDS STATEMENT...ILZ006-ILZ014 UNTIL 5 PM SATURDAY.
IN...BEACH HAZARDS STATEMENT...INZ001-INZ002 UNTIL 5 PM SATURDAY.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 10 PM FRIDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
[top]
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
259 PM CDT Thu Sep 11 2014
.SHORT TERM...(Tonight)
ISSUED AT 259 PM CDT THU SEP 11 2014
Cold front just south of the Ohio River Valley this afternoon as
high pressure builds into the Midwest. Northerly flow at the sfc
bringing unseasonably cool temps into the region, in stark contrast
to the weather of the last few days. Cooler temperatures expected
to continue into the overnight hours. With lows dipping into the
upper 40s across the nrn portions of the state...and low 50s before
dawn for much of Illinois. Breaks in the cloud cover off to the
west not having much success in moving into the region. As a
result, continued cloud coverage expected through the overnight
hours as llvl RH has remained trapped. Both NAM and HRRR slow to
move clouds out, though some brief clearing is possible NW of the
Illinois River.
&&
.LONG TERM...(Friday through Thursday)
ISSUED AT 259 PM CDT THU SEP 11 2014
Cool and cloudy conditions are expected again Friday as low level
northerly flow continues with a strong capping inversion at around
850 mb. An upper level shortwave will be rapidly approaching from
the west. The axis of the shortwave expected to cross Illinois late
Friday evening to early Saturday morning...pushing another frontal
boundary through the region. Current model forecasts are fairly
consistent keeping precipitation with this feature mainly north of
I-72...and modest amounts around 0.10 inches or less. Have PoPs
beginning Friday afternoon west of I-55 as lift associated with the
approaching shortwave begins...then PoPs spread through most areas
I-55 northward Friday evening. The system moves rapidly east-
northeastward leaving a cool and dry weekend behind it...with highs
in the 60s and lows in the 40s...as high pressure settles over the
area.
The next chance for precipitation will be Monday as models
consistently track another broad trough through the midwest. Cool
dry northwesterly flow aloft is expected to follow for the remainder
of the week with little chance for any precipitation and below
normal temperatures continuing.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
ISSUED AT 1234 PM CDT THU SEP 11 2014
Not much in the way of a change in the forecast. MVFR continuing,
with some IFR conditions still possible today as cigs are right on
the cusp btwn two categories above and below 1kft. Some breaks in
the clouds are still well to the west and northwest. Models are
breaking between some drying out of the low levels and the NAM
holding on to the higher RH below 850mb. HRRR keeping MVFR through
the day with some breaks approaching PIA, but certainly not
predominant and will amend accordingly should the sun break
through. However, the HRRR going into the evening hours starts to
drop the cigs once again, with IFR very near. Not going that
pessimistic just yet, but not clearing the MVFR through the end of
the fcst pd. North/northeast winds throughout.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...HJS
LONG TERM...ONTON
AVIATION...HJS
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1255 PM CDT THU SEP 11 2014
.DISCUSSION...
339 AM CDT
WHAT A DIFFERENCE A DAY MAKES...AS THE FIRST REAL AUTUMN-LIKE
PUSH OF COOL AIR SPREADS INTO THE MIDWEST TODAY IN THE WAKE OF
YESTERDAYS COLD FRONT. MAIN FOCUS OF THE FORECAST ARE THESE MID
OCTOBER-LIKE TEMPERATURES OVER THE NEXT SEVERAL DAYS...A CHANCE OF
RAIN FRIDAY AND FRIDAY NIGHT...AND EVEN THE POTENTIAL FOR SOME
LAKE EFFECT RAIN SHOWERS AS OUR UNSEASONABLY COOL AIR SPREADS OVER
THE RELATIVELY WARM LAKE MICHIGAN WATERS.
DEEP SURFACE LOW PRESSURE WHICH MOVED ACROSS THE UPPER MIDWEST
WEDNESDAY WAS PULLING AWAY ACROSS SOUTHWESTERN QUEBEC PER EARLY
MORNING ANALYSIS...WITH THE TRAILING COLD FRONT PUSHING THROUGH THE
LOWER OHIO VALLEY. MUCH COOLER WAS SPREADING IN FROM THE NORTH AND
NORTHWEST...WITH UPSTREAM TEMPS IN THE MID-40S ACROSS MINNESOTA AND
WISCONSIN AND EVEN A FEW LOW-MID 30S NOTED UP IN THE MINNESOTA
ARROWHEAD. THIS COOL AIR MASS WILL CONTINUE TO SPREAD INTO THE GREAT
LAKES AND MIDWEST TODAY AS SPRAWLING CANADIAN HIGH PRESSURE MOVES
SLOWLY SOUTHEAST ACROSS THE NORTHERN PLAINS AND UPPER MIDWEST. IR
SATELLITE IMAGERY SHOWS EXTENSIVE LOW CLOUD SHIELD ACROSS MUCH OF
THE UPPER MIDWEST...AND WITH ONLY WEAK SUBSIDENCE NOTED IN MODEL
TIME HEIGHT SECTIONS IT APPEARS THAT CLOUD COVER WILL BE SLOW TO
ERODE IN PERSISTENT COOL ADVECTION REGIME TODAY. LOW LEVEL THERMAL
PROGS AND GUIDANCE NUMBERS ALL POINT TO HIGHS RANGING FROM AROUND 60
NEAR THE IL/WI BORDER TODAY...TO THE LOW-MID 60S FAR SOUTH IN EAST
CENTRAL IL. TO PUT THESE TEMPS INTO PERSPECTIVE...61 IS THE RECORD
LOW MAXIMUM TEMP FOR TODAY/SEPTEMBER 11 FOR CHICAGO...WHICH WOULD BE
NORMAL HIGH TEMPERATURE RANGE FOR MID-LATE OCTOBER. EXTENSIVE CLOUD
COVER AND A MODEST NORTH WIND WILL HELP KEEP TEMPS IN THE 40S
TONIGHT.
850 MB TEMPS LOWER TO ABOUT +2 OR +3 C TONIGHT...WITH SOUTHERN LAKE
MICHIGAN WATER TEMPERATURES IN THE LOW-MID 60S F. FORECAST SOUNDINGS
DEPICT A RISING INVERSION LEVEL TONIGHT INTO EARLY FRIDAY WHICH
WOULD SUPPORT LAKE-INDUCED INSTABILITY CLOUDS AND POSSIBLY SOME
LIGHT SPRINKLES OR SHOWERS...MAINLY LATE TONIGHT INTO EARLY FRIDAY
AS THE INVERSION HEIGHT INCREASES. LOW LEVEL WINDS TURN
NORTHEASTERLY DURING THIS TIME WHICH MAY BRING A FEW OF THESE LIGHT
SHOWERS INTO NORTHEAST IL.
A GREATER CHANCE OF RAIN THEN LOOKS TO DEVELOP ACROSS THE AREA
FRIDAY...AS THE STRONG DIGGING SHORT WAVE SEEN IN CURRENT WATER
VAPOR IMAGERY ACROSS THE NORTHERN ROCKIES APPROACHES. IMPRESSIVE
FORCING FOR VERTICAL MOTION DEVELOPS PER MODEL OMEGA/Q-VECTOR
CONVERGENCE FIELDS AS THIS WAVE PROPAGATES ALONG THE ELEVATED
BAROCLINIC ZONE ASSOCIATED WITH OUR RECENT LOW LEVEL COOL AIR
INTRUSION. STRONG HEIGHT FALLS AND STRENGTHENING UPPER JET CORE
DEVELOP ALOFT...WITH LOWER LEVEL FRONTOGENETIC FORCING ALSO
INCREASING ESPECIALLY FRIDAY AFTERNOON/NIGHT AS THE TROUGH NEARS.
GUIDANCE IN GOOD AGREEMENT IN DEVELOPING RAIN ACROSS NORTHWEST HALF
OF THE CWA FRIDAY...AND ACROSS THE REMAINDER OF THE FORECAST AREA
FRIDAY NIGHT WITH GENERALLY 0.15-0.25 INCHES OF QPF. SHARP MID-LEVEL
TROUGH AXIS PASSES TOWARD SUNRISE SATURDAY MORNING...WITH QUICK
SHUT-OFF OF PRECIPITATION EXPECTED GIVEN STRONG MID-LEVEL SUBSIDENCE
AND SHARPLY RISING HEIGHTS BEHIND THE SHORT WAVE. EXCEPTION MAY BE
ALONG THE LAKE AND INTO NORTHWEST INDIANA SATURDAY MORNING AS SOME
POTENTIAL FOR LAKE EFFECT SHOWERS WILL LINGER UNTIL SUBSIDENCE
INVERSION STRENGTHENS AND LOWERS ENOUGH TO LIMIT DEPTH OF
INSTABILITY OVER THE LAKE WATERS.
SURFACE HIGH PRESSURE RIDGE DEVELOPS ACROSS THE REGION IN THE WAKE
OF THE STRONG DEPARTING MID-LEVEL WAVE SATURDAY AFTERNOON AND NIGHT
WITH GOOD POTENTIAL FOR SCOURING OUT CLOUDS. CLEARING LIKELY TO BE
OCCURRING TOWARD SUNRISE SATURDAY FROM THE WEST WITH SOME NORTH WIND
LIKELY KEEPING TEMPS FROM BOTTOMING OUT...THOUGH SOME AREAS NOT FAR
WEST/NORTH OF THE CWA COULD SEE SATURDAY NIGHT/SUNDAY AM MINS IN
THE 30S. DESPITE THE RETURN OF SUNSHINE NOT MUCH CHANGE IN HIGH
TEMPERATURE IS EXPECTED SATURDAY WITH REINFORCING PUSH OF COOLER AIR
AHEAD OF THE HIGH OFFSETTING ANY GAINS FROM MORE SUNSHINE. TEMPS IN
THE LOW 60S/LOWS IN THE 40S EXPECTED SATURDAY AND SATURDAY NIGHT...
THOUGH THE PROSPECT FOR A FEW SUNDAY AM LOWS IN THE 30S CANT BE
RULED OUT WITH LIGHT WINDS AND POTENTIALLY CLEAR SKIES.
THE SURFACE HIGH PRESSURE RIDGE DRIFTS SOUTHEAST AND WEAK WARM
ADVECTION RETURNS ON SUNDAY. RELATIVELY MODEST GAINS IN TEMPS
EXPECTED HOWEVER WITH MAX TEMPS MODERATING ONLY TO THE 65-70 RANGE
INTO EARLY NEXT WEEK AS ANOTHER MID-LEVEL WAVE APPROACHES. NEXT
CHANCE OF RAIN ACCOMPANIES THIS SYSTEM ON MONDAY.
RATZER
&&
.CLIMATE...
915 AM CDT SEP 11 2014
AN UNSEASONABLY COOL AIR MASS OVER THE REGION INTO THE WEEKEND
COULD PUT SOME RECORD TEMPERATURES IN JEOPARDY AT CHICAGO AND
ROCKFORD. RECORD LOW MAX TEMPERATURES ARE MOST LIKELY TO BE
THREATENED.
RECORD LOW MAX TEMPERATURES SEPTEMBER 11-13
-------------------------------------------
SEPTEMBER 11 SEPTEMBER 12 SEPTEMBER 13
------------ ------------ ------------
CHICAGO 61/1940 53/1902 55/1880
ROCKFORD 55/1914 56/1943 55/1970
RC
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* MVFR CIGS THROUGH THE PERIOD...WITH POTENTIAL FOR IFR LATE
TONIGHT INTO FRIDAY MORNING.
* NORTH-NORTHEAST WINDS 350-020 DEG AROUND 10 KT BECOMING MORE
NORTHEAST 020-040 DEG AROUND 10 KT BY ABOUT 20Z.
* LAKE EFFECT SHOWERS LATE TONIGHT INTO FRIDAY MORNING.
* NORTH-NORTHEAST WINDS AROUND 10 KT BECOMING NORTHEAST ON FRIDAY.
* RAIN SHOWERS MOVING INTO AREA LATE FRIDAY AFTERNOON...WITH
PREVAILING RAIN AND CIG/VSBY IMPACTS MORE LIKELY FRIDAY EVE.
RC
//DISCUSSION...UPDATED 18Z...
UNSEASONABLY COOL AIR MASS OVER THE REGION IS RESULTING IN SEVERAL
CONCERNS THIS PERIOD. MOISTURE LOCKED UNDER INVERSION IS KEEPING
STRATUS DECK IN PLACE THIS AFTERNOON AND NOW EXPECT PRIMARILY MVFR
CIGS THROUGH THE PERIOD. THE COOL AIR MASS MOVING OVER THE MILD
LAKE WATERS WILL LIKELY RESULT IN THE DEVELOPMENT OF LAKE EFFECT
SHOWERS LATE TONIGHT INTO FRIDAY MORNING. HIGHER RESOLUTION
GUIDANCE HINTS THAT DECENT BAND COULD EVEN SET UP INTO NORTHWEST
INDIANA INITIALLY AND THEN GRADUALLY SHIFT NORTHEAST. HAVE MEDIUM
TO HIGH CONFIDENCE THAT THERE WILL BE SHOWERS AROUND...BUT LOW
CONFIDENCE IN DIRECT IMPACTS TO ORD/MDW/GYY...THUS HAVE CARRIED
VCSH MENTION. IF SHRA ARE MORE ORGANIZED AND DIRECTLY IMPACT
TERMINALS...THERE COULD BE IMPACTS TO VSBY.
ONSHORE FLOW IS EXPECTED TO ALSO RESULT IN LOWERING OF MVFR
CIGS AT EASTERN TERMINALS...WITH SOME GUIDANCE MEMBERS INDICATING
POTENTIAL FOR IFR. HAVE HINTED AT THIS WITH SCT IFR CLOUDS IN TAF.
A FAIRLY STRONG UPPER LEVEL DISTURBANCE AND REINFORCING SHOT OF
COOL AIR WILL MOVE ACROSS REGION DURING THE DAY ON FRIDAY...AND
THIS WILL RESULT IN RAIN SHOWERS SPREADING IN FROM NORTHWEST.
PREVAILING RAIN SHOWERS ARE EXPECTED IN ROCKFORD VICINITY DURING
AFTERNOON...BUT NOT UNTIL BEYOND THE 30 HOUR ORD TAF AT THE
EASTERN TAF SITES.
REGARDING WINDS...PREDOMINANTLY NORTHERLY WINDS EARLY THIS
AFTERNOON ARE EXPECTED TO SHIFT TO NORTHEAST OR NORTH-NORTHEAST
LATER THIS AFTERNOON INTO THE EVENING. IF AN ORGANIZED LAKE EFFECT
BAND SETS UP INTO NORTHEAST ILLINOIS OVERNIGHT...WINDS MAY TREND
MORE NORTHERLY OR EVEN NORTH-NORTHWEST...BUT THEN NORTHEAST WINDS
AROUND 10 KT ARE EXPECTED FRIDAY MORNING THROUGH THE END OF THE
PERIOD.
RC
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM-HIGH IN MVFR CIGS CONTINUING THROUGH THE PERIOD. LOW IN
IFR LATE TONIGHT INTO FRIDAY.
* MEDIUM IN WIND TRENDS THROUGH THE PERIOD. MEDIUM-HIGH IN SPEEDS
AROUND 10 KT WITH NORTH-NORTHEAST WINDS THIS AFTERNOON.
* MEDIUM-HIGH IN LAKE EFFECT SHOWERS DEVELOPING TONIGHT...LOW IN
DIRECT IMPACTS TO TERMINALS.
* MEDIUM IN PREVAILING RAIN SHOWERS MORE LIKELY TO MOVE IN FRIDAY
EVENING.
RC
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...SHRA LIKELY. MVFR/IFR CIGS PSBL.
SATURDAY...VFR. GUSTY NW WINDS IN THE MORNING.
SUNDAY...VFR.
MONDAY...CHC SHRA DURING THE DAY. MVFR CIGS PSBL.
TUESDAY AND WEDNESDAY...VFR
KMD
&&
.MARINE...
356 AM CDT
STRONG EARLY FALL LOW PRESSURE SYSTEM HAS KICKED OUT TO THE
NORTHEAST EARLY THIS MORNING AND WILL CONTINUE ITS TREK NORTHEAST
THROUGH QUEBEC OVER THE COMING DAYS. THIS SYSTEM COMBINED WITH A
STRONG COLD FRONT HAS LED TO 40-45 KT GALES EARLY THIS MORNING...AND
IN SPITE OF THE BUOYS SHOWING A TREND DOWNWARD...STILL SEEING SHIP
OBS OF 40 KT ALONG THE WEST HALF OF LAKE.
AS THE LOW MOVES OUT OF THE AREA...THE LINGERING GRADIENT WILL
CONTINUE TO EASE...THUS GALE FORCE GUSTS SHOULD LARGELY BE DONE BY
LATE MORNING. ALSO...WITH HIGH PRESSURE BUILDING INTO THE
PLAINS...THIS WILL MAINTAIN A FETCH OF NORTHERLY WINDS DOWN THE LAKE
AND KEEP WAVES ELEVATED THROUGH THE REST OF THE WEEK.
A SECONDARY COLD FRONT WILL PASS THROUGH THE LAKE FRIDAY NIGHT AND
WILL REINFORCE THE GUSTY NORTHERLY WINDS ON THE SOUTHERN HALF OF THE
LAKE AS A WEAK LOW DEVELOPS AHEAD OF THE FRONT. AT THIS POINT WAVES
WOULD HAVE BEEN GRADUALLY SUBSIDING DUE TO A WEAKENING WIND
FIELD...SO THIS FRONT WILL REBUILD WAVES AGAIN...ESPECIALLY ALONG
THE INDIANA SHORELINE. THE HIGH WILL THEN BUILD OVERHEAD FOR THE
WEEKEND.
KMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...BEACH HAZARDS STATEMENT...ILZ006-ILZ014 UNTIL 5 PM SATURDAY.
IN...BEACH HAZARDS STATEMENT...INZ001-INZ002 UNTIL 5 PM SATURDAY.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 10 PM FRIDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1241 PM CDT Thu Sep 11 2014
.UPDATE...
ISSUED AT 1057 AM CDT THU SEP 11 2014
Northerly winds and cooler temperatures advecting into the area
this morning under cloudy skies. Very little clearing anticipated
today as any clearing on sat imagery is well off to the NW. Sun
may cause a few breaks in the clouds by later this
afternoon/evening. Forecast going well and no updates are
anticipated at this time.
&&
.SHORT TERM...(Today)
ISSUED AT 229 AM CDT THU SEP 11 2014
07z/1am surface analysis shows cold front settling southward toward
the Ohio River, with all its associated precip now south of the KILX
CWA. Behind the boundary, extensive low cloud cover is noted on IR
satellite imagery across Illinois northward into Wisconsin/Minnesota.
With northerly winds expected to prevail throughout the day, think
clouds will remain in place, especially given presence of very
strong inversion at around 900mb. Models have different opinions
concerning sky cover today, with MAV guidance indicating partial
clearing and MET keeping conditions overcast. Given current
satellite imagery and developing inversion, think the pessimistic
MET solution is the way to go. As a result, have increased sky
cover to go with a mostly cloudy forecast today. Have also lowered
high temps due to clouds and strong CAA, with readings only rising
into the lower to middle 60s.
&&
.LONG TERM...(Tonight through Wednesday)
ISSUED AT 229 AM CDT THU SEP 11 2014
Another unseasonably cool day is on tap for Friday as N/NE flow
continues and skies remain partly to mostly cloudy. 500mb trough
currently over the Northern Rockies will track southeastward,
with the trough axis passing through Illinois Friday night. As has
been advertised for the past several model runs, clouds and
perhaps a few showers will accompany the trough, although models
differ on how much precip may occur. NAM continues to be rather
aggressive with its QPF, while both the GFS and ECMWF are drier
and more diurnally driven. Given dry airmass in place ahead of
this feature, prefer the GFS/ECMWF consensus here. Have introduced
chance PoPs across the western half of the CWA Friday afternoon as
the wave approaches, but have dropped PoPs to just slights Friday
night as daytime instability diminishes and lapse rates become
less steep.
Once the Friday night trough passes, strong Canadian high pressure
will provide cool and dry conditions this weekend. Temperatures
will begin to slowly moderate through the period, with highs
reaching the upper 60s and lower 70s by Sunday. After that, the
next northern stream short-wave will arrive early next week, with
the 00z Sep 11 models now in better agreement concerning its
timing. With fairly robust wave arriving on Monday, think clouds
and scattered showers are a good bet. This feature will quickly
track off to the east, resulting in a return to dry weather for
Tuesday and Wednesday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
ISSUED AT 1234 PM CDT THU SEP 11 2014
Not much in the way of a change in the forecast. MVFR continuing,
with some IFR conditions still possible today as cigs are right on
the cusp btwn two categories above and below 1kft. Some breaks in
the clouds are still well to the west and northwest. Models are
breaking between some drying out of the low levels and the NAM
holding on to the higher RH below 850mb. HRRR keeping MVFR through
the day with some breaks approaching PIA, but certainly not
predominant and will amend accordingly should the sun break
through. However, the HRRR going into the evening hours starts to
drop the cigs once again, with IFR very near. Not going that
pessimistic just yet, but not clearing the MVFR through the end of
the fcst pd. North/northeast winds throughout.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HJS
SHORT TERM...BARNES
LONG TERM...BARNES
AVIATION...HJS
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
250 PM CDT THU SEP 11 2014
...UPDATED LONG TERM SECTION...
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 157 PM CDT THU SEP 11 2014
STATUS LINGERING ACROSS MOST OF SOUTHWEST AND WESTERN KANSAS EARLY THIS
AFTERNOON HAS REDUCED THE CHANCE FOR SURFACE BASED CONVECTION LATE
TODAY. AT THIS TIME HOWEVER A FEW SCATTERED ELEVATED SHOWERS OR
EVEN AN ISOLATED THUNDERSTORM WILL STILL BE POSSIBLE THROUGH EARLY
EVENING ACROSS FAR WESTERN KANSAS, MAINLY WEST OF HIGHWAY 83. THIS
IS BASED ON THE MOISTURE AND WARM AIR ADVECTION FORECAST AROUND
THE 700MB LEVEL AND ELEVATED CAPE VALUES BETWEEN 00Z AND 03Z
FRIDAY FROM THE NAM AND ARW.
MODELS TODAY REMAINED IN GOOD AGREEMENT WITH A REINFORCEMENT OF
COLDER AIR CROSSING WESTERN KANSAS LATE TONIGHT AS A COLD DOME OF
HIGH PRESSURE, LOCATED OVER EASTERN MONTANA AT 12Z THURSDAY, MOVES
SOUTHEAST INTO EASTERN WYOMING AND WESTERN NEBRASKA BY 12Z FRIDAY.
AS THIS COLDER AIR INVADES WESTERN KANSAS....GUSTY NORTHEAST WINDS
WILL DEVELOP. BASED ON THE MEAN WINDS FROM THE SURFACE TO 0.5KM
WINDS, 925MB TO 850MB WINDS AND WITH 12Z NAM BUFR SOUNDINGS IT
APPEARS WIND SPEEDS WILL BRIEFLY APPROACH ADVISORY CRITERIA
BETWEEN 09Z AND 15Z FRIDAY WEST OF HIGHWAY 83. GIVEN THE COLD AIR
ADVECTION ADVERTISED BY THE NAM AND GFS THE TEMPERATURES OVERNIGHT
WILL CONTINUE TO FAVOR THE PREVIOUS FORECAST WHICH WAS A FEW
DEGREES BELOW THE COOLER GUIDANCE DESPITE THE CLOUD COVER
EXPECTED. LOWS TONIGHT ARE STILL EXPECTED TO RANGE FROM THE LOWER
40S TO NEAR 50 DEGREES.
WIDESPREAD RAINFALL WILL IMPROVE ACROSS ALL OF WESTERN KANSAS
LATER TONIGHT AND THEN CONTINUE THROUGH FRIDAY AS A MID LEVEL
BAROCLINIC ZONE AHEAD OF AN UPPER LEVEL TROUGH CROSSES THE CENTRAL
PLAINS. THE BETTER FORCING FOR THIS PRECIPITATION TONIGHT AND
FRIDAY WILL OCCUR ALONG A BAND OF 850MB TO 700MB FRONTOGENISIS
THAT WILL MOVE FROM WEST CENTRAL KANSAS AT 06Z FRIDAY TO SOUTH
CENTRAL KANSAS BETWEEN 15Z AND 18Z FRIDAY. AFTER 18Z THE
PRECIPITATION IS EXPECTED TO TAPER OFF FROM NORTHWEST TO SOUTHEAST
AS THE MID LEVEL BAROCLINIC ZONE MOVES INTO CENTRAL KANSAS AND
NORTHERN OKLAHOMA. THERE MAY ALSO BE SOME CLEARING NEAR THE
COLORADO BORDER LATE IN THE DAY FRIDAY AS SUBSIDENCE DEVELOPS
BEHIND THE UPPER LEVEL TROUGH THAT WILL BE CROSSING NEBRASKA AND
KANSAS DURING THE DAY ON FRIDAY. LITTLE DIURNAL CHANGE IN
TEMPERATURES WILL OCCUR ACROSS WESTERN KANSAS BETWEEN THURSDAY
NIGHT LOWS AND HIGHS FRIDAY AFTERNOON BASED ON CLOUD COVER AND
PRECIPITATION CHANCES THROUGH MUCH OF THE DAY. TAKING THIS INTO
ACCOUNT WILL STAY CLOSE TO THE LATEST GUIDANCE ACROSS PORTIONS
WESTERN KANSAS WHERE SOME BREAKS OF SUN WILL BE POSSIBLE LATE
FRIDAY. WILL UNDERCUT GUIDANCE FURTHER EAST.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 318 AM
CDT THU SEP 11 2014
FRIDAY AND SATURDAY WILL BE RECOVERY DAYS FROM THE RELATIVELY COOL
AND CLOUDY CONDITIONS FROM THE PREVIOUS WAVE. THE WAVE WILL BE
EXITING THE REGION ON FRIDAY EVENING, LEAVING IN IT`S WAKE ZONAL
WINDS ALOFT AND INCREASINGLY COOL AND DRY BOUNDARY LAYER ON
SATURDAY. EARLY SATURDAY MORNING, TEMPERATURES WILL PROBABLY PLUMMET
INTO THE UPPER 30S IN SOME AREAS OF THE WEST CENTRAL AND CENTRAL
COUNTIES WHERE LIGHT WINDS LOW DEW POINTS AND CLEARING SKIES FAVOR
EFFICIENT LONGWAVE RADIATIONAL COOLING. HOWEVER TEMPERATURES WILL
STILL WARM AT THE SURFACE DUE TO INCREASED INSOLATION WITH
TEMPERATES RISING THROUGH THE 60S BY SATURDAY AFTERNOON, AND A
LARGER JUMP ON STRONGER SOUTHERLY /SOUTHWEST WINDS ON SUNDAY INTO
THE LOW TO MID 80S IN SOME AREAS.
BY SUNDAY NIGHT OR EARLY MONDAY ALL OF THE MODELS BEGIN TO SHOW THE
NEXT PV ANOMALY MOVING THROUGH THE FLOW ACROSS THE GREAT LAKE REGION
WITH A WEAK TROUGH/DEFORMATION ZONE EXTENDING SOUTH THROUGH THE
CENTRAL PLANS IN VICINITY OF CENTRAL KANSAS. POPS HAVE CONTINUED TO
BE CARRIED FOR THUNDERSTORM CHANCES IN THIS PERIOD AS THE GFS MODEL
SOUNDINGS DO APPEAR TO SUPPORT THE POTENTIAL WITH NEAR SATURATED
PROFILES NEAR THE LCL AND JUST BELOW LFC MONDAY. BEYOND THAT,
CONVECTION COULD ALSO OCCUR ANY GIVEN DAY AS WEAK SOUTHERLY 850 MB
MOISTURE TRANSPORT SIGNALS CONTINUE ACROSS THE HIGH PLAINS REGION
TUESDAY AND WEDNESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1208 PM CDT THU SEP 11 2014
BUFR SOUNDINGS AND HRRR BOTH IN GOOD AGREEMENT WITH IFR AND LIFR
CEILINGS GRADUALLY IMPROVING THROUGH THE EARLY AFTERNOON WITH A
BRIEF PERIOD OF VFR CONDITIONS DEVELOPING AT GCK AND DDC AFTER
21Z. CLOUD BASES WILL THEN LOWER ONCE AGAIN BACK INTO THE 700 TO
1500FT AGL LEVEL AFTER 00Z FRIDAY AS MORE HUMID AIR RETURNS TO
SOUTHWEST KANSAS. IN ADDITION TO THE LOWERING CEILINGS EARLY
TONIGHT PERIODS OF LIGHT RAIN AND/OR DRIZZLE CAN BE EXPECTED LATE
TONIGHT THROUGH EARLY FRIDAY. NORTHEASTERLY WINDS AT 15 TO 20
KNOTS THIS AFTERNOON WILL BECOME MORE NORTHERLY AFTER 06Z AND THEN
INCREASE TO 20 TO NEAR 25 KNOTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 46 53 40 65 / 90 80 0 0
GCK 43 50 38 67 / 90 80 0 0
EHA 42 51 43 71 / 90 80 0 0
LBL 47 54 42 69 / 90 80 0 0
HYS 42 52 38 64 / 90 80 0 0
P28 52 58 43 67 / 40 60 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...MR
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
200 PM CDT THU SEP 11 2014
...UPDATED SHORT TERM DISCUSSION...
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 157 PM CDT THU SEP 11 2014
STATUS LINGERING ACROSS MOST OF SOUTHWEST AND WESTERN KANSAS EARLY THIS
AFTERNOON HAS REDUCED THE CHANCE FOR SURFACE BASED CONVECTION LATE
TODAY. AT THIS TIME HOWEVER A FEW SCATTERED ELEVATED SHOWERS OR
EVEN AN ISOLATED THUNDERSTORM WILL STILL BE POSSIBLE THROUGH EARLY
EVENING ACROSS FAR WESTERN KANSAS, MAINLY WEST OF HIGHWAY 83. THIS
IS BASED ON THE MOISTURE AND WARM AIR ADVECTION FORECAST AROUND
THE 700MB LEVEL AND ELEVATED CAPE VALUES BETWEEN 00Z AND 03Z
FRIDAY FROM THE NAM AND ARW.
MODELS TODAY REMAINED IN GOOD AGREEMENT WITH A REINFORCEMENT OF
COLDER AIR CROSSING WESTERN KANSAS LATE TONIGHT AS A COLD DOME OF
HIGH PRESSURE, LOCATED OVER EASTERN MONTANA AT 12Z THURSDAY, MOVES
SOUTHEAST INTO EASTERN WYOMING AND WESTERN NEBRASKA BY 12Z FRIDAY.
AS THIS COLDER AIR INVADES WESTERN KANSAS....GUSTY NORTHEAST WINDS
WILL DEVELOP. BASED ON THE MEAN WINDS FROM THE SURFACE TO 0.5KM
WINDS, 925MB TO 850MB WINDS AND WITH 12Z NAM BUFR SOUNDINGS IT
APPEARS WIND SPEEDS WILL BRIEFLY APPROACH ADVISORY CRITERIA
BETWEEN 09Z AND 15Z FRIDAY WEST OF HIGHWAY 83. GIVEN THE COLD AIR
ADVECTION ADVERTISED BY THE NAM AND GFS THE TEMPERATURES OVERNIGHT
WILL CONTINUE TO FAVOR THE PREVIOUS FORECAST WHICH WAS A FEW
DEGREES BELOW THE COOLER GUIDANCE DESPITE THE CLOUD COVER
EXPECTED. LOWS TONIGHT ARE STILL EXPECTED TO RANGE FROM THE LOWER
40S TO NEAR 50 DEGREES.
WIDESPREAD RAINFALL WILL IMPROVE ACROSS ALL OF WESTERN KANSAS
LATER TONIGHT AND THEN CONTINUE THROUGH FRIDAY AS A MID LEVEL
BAROCLINIC ZONE AHEAD OF AN UPPER LEVEL TROUGH CROSSES THE CENTRAL
PLAINS. THE BETTER FORCING FOR THIS PRECIPITATION TONIGHT AND
FRIDAY WILL OCCUR ALONG A BAND OF 850MB TO 700MB FRONTOGENISIS
THAT WILL MOVE FROM WEST CENTRAL KANSAS AT 06Z FRIDAY TO SOUTH
CENTRAL KANSAS BETWEEN 15Z AND 18Z FRIDAY. AFTER 18Z THE
PRECIPITATION IS EXPECTED TO TAPER OFF FROM NORTHWEST TO SOUTHEAST
AS THE MID LEVEL BAROCLINIC ZONE MOVES INTO CENTRAL KANSAS AND
NORTHERN OKLAHOMA. THERE MAY ALSO BE SOME CLEARING NEAR THE
COLORADO BORDER LATE IN THE DAY FRIDAY AS SUBSIDENCE DEVELOPS
BEHIND THE UPPER LEVEL TROUGH THAT WILL BE CROSSING NEBRASKA AND
KANSAS DURING THE DAY ON FRIDAY. LITTLE DIURNAL CHANGE IN
TEMPERATURES WILL OCCUR ACROSS WESTERN KANSAS BETWEEN THURSDAY
NIGHT LOWS AND HIGHS FRIDAY AFTERNOON BASED ON CLOUD COVER AND
PRECIPITATION CHANCES THROUGH MUCH OF THE DAY. TAKING THIS INTO
ACCOUNT WILL STAY CLOSE TO THE LATEST GUIDANCE ACROSS PORTIONS
WESTERN KANSAS WHERE SOME BREAKS OF SUN WILL BE POSSIBLE LATE
FRIDAY. WILL UNDERCUT GUIDANCE FURTHER EAST.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 318 AM CDT THU SEP 11 2014
FRIDAY WILL BE COOL AND MOIST, WITH LIGHT RAIN LIKELY.
FRIDAY WILL BE IN A POST FRONTAL REGIME, WITH COOL HIGH PRESSURE
BUILDING IN FROM THE NORTHWEST. THE SURFACE FLOW WILL BE UPSLOPE
WITH NORTHEAST TO EASTERLY WINDS AT 10 TO 20 MPH. CLOUDS WILL BE
THICKEST IN THE MORNING, BUT STILL PREVALENT IN THE AFTERNOON. MAX
TEMPS WILL GENERALLY BE IN THE 50S, BUT I ONLY EXPECT LIGHT RAIN
WITH 0.05 TO 0.10 INCH ACCUMULATION. THE HIGH PRESSURE WILL BEGIN
TO DOMINATE FRIDAY EVENING, LEADING TO CLEAR SKIES OVERNIGHT. THE
COOL AIR WILL FILTRATE IN FROM THE NORTHWEST, AND FROST MAY BE
POSSIBLE IN OUR EXTREME NORTHWESTERN COUNTIES OF TREGO, AND
NORTHERN LANE AND SCOTT COUNTIES SATURDAY MORNING. AS THAT TIME
FRAME APPROACHES, WE WILL NEED TO LOOK INTO A POSSIBLE WATCH OR
REFINE THE AREA WHERE FROST MAY OCCUR.
AFTER THE FALL-LIKE WEATHER ON FRIDAY, SATURDAY AND SUNDAY WILL
SHOW A GRADUAL WARM UP, WITH HIGHS REACHING THE MID 60S TO LOWER
70S ON SATURDAY, AND BOUNDING UPWARD TO THE UPPER 70S TO LOWER 80S
BY SUNDAY. A COLD FRONT WILL PLOW THROUGH TO THE SOUTHEAST ON
MONDAY AFTERNOON, BRINGING A CHANCE FOR THUNDERSTORMS TO OUR
SOUTHEAST-MOST ZONES, PRIMARILY IN PRATT AND BARBER COUNTIES. AN
UPPER LEVEL WAVE WILL COME THROUGH IN THE FLOW MONDAY NIGHT,
GIVING MOST OF THE CWA A 20 TO 30 PERCENT CHANCE FOR
THUNDERSTORMS. A LEE SIDE TROUGH WILL BE IN WESTERN KANSAS TUESDAY
AND WEDNESDAY, AND SLIGHT CHANCES FOR SHOWERS AND ISOLATED
THUNDERSTORMS WILL EXIST ACROSS MOST OF OUR FORECAST AREA, MAINLY
THE EAST.
WEDNESDAY WILL SEE A RETURN TO A WARM SOUTHWEST FLOW, AND HIGH
TEMPERATURES WILL RESPOND LIKEWISE WITH VALUES IN THE LOWER 80S
NORTH OF I-70 AND THE MIDDLE 80S SOUTHWEST A LINE FROM GARDEN CITY
TO DODGE CITY TO MEDICINE LODGE. WINDS THROUGH THE EXTENDED DO NOT
LOOK TOO STRONG, EXCEPT AHEAD OF THE FRONT ON MONDAY, AND THEN
AGAIN BEHIND THE FRONT ON TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1208 PM CDT THU SEP 11 2014
BUFR SOUNDINGS AND HRRR BOTH IN GOOD AGREEMENT WITH IFR AND LIFR
CEILINGS GRADUALLY IMPROVING THROUGH THE EARLY AFTERNOON WITH A
BRIEF PERIOD OF VFR CONDITIONS DEVELOPING AT GCK AND DDC AFTER
21Z. CLOUD BASES WILL THEN LOWER ONCE AGAIN BACK INTO THE 700 TO
1500FT AGL LEVEL AFTER 00Z FRIDAY AS MORE HUMID AIR RETURNS TO
SOUTHWEST KANSAS. IN ADDITION TO THE LOWERING CEILINGS EARLY
TONIGHT PERIODS OF LIGHT RAIN AND/OR DRIZZLE CAN BE EXPECTED LATE
TONIGHT THROUGH EARLY FRIDAY. NORTHEASTERLY WINDS AT 15 TO 20
KNOTS THIS AFTERNOON WILL BECOME MORE NORTHERLY AFTER 06Z AND THEN
INCREASE TO 20 TO NEAR 25 KNOTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 45 53 40 65 / 90 80 0 0
GCK 42 50 38 67 / 90 80 0 0
EHA 45 51 43 71 / 90 80 0 0
LBL 48 54 42 69 / 90 80 0 0
HYS 42 52 38 64 / 90 80 0 0
P28 50 58 43 67 / 40 60 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...BURKE
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1212 PM CDT THU SEP 11 2014
...UPDATED SYNOPSIS AND AVIATION DISCUSSION...
.SYNOPSIS...
ISSUED AT 1208 PM CDT THU SEP 11 2014
AT 12Z THURSDAY A -28C 500MB LOW WAS LOCATED OVER WESTERN MONTANA
WITH A +100 KNOT 300MB JET EXTENDING FROM THE BASED OF THIS UPPER
LOW NEAR SOUTHERN IDAHO EASTWARD INTO SOUTH DAKOTA. A 700MB
BAROCLINIC ZONE STRETCHED FROM EASTERN IDAHO TO SOUTHEAST WYOMING
AND ACROSS CENTRAL NEBRASKA. THIS IS ALSO WHERE AN AREA OF HIGHER
850MB AND 700MB MOISTURE APPEARS TO BE LOCATED EARLIER THIS
MORNING. AN 850MB COLD FRONT WAS LOCATED FROM SOUTHEAST COLORADO
TO NORTH CENTRAL KANSAS WITH A MOISTURE UPSLOPE FLOW FROM THE
SURFACE TO THE 850MB LEVEL JUST NORTH OF THIS BOUNDARY. DODGE CITY
SOUNDINGS HAD THE DEPTH OF THIS LOW LEVEL MOISTURE AROUND 3000FT
AGL. A ENFORCEMENT OF COOLER AIR AT 850MB LEVEL APPEARS TO EXTEND
FROM SOUTHEAST WYOMING TO SOUTHERN IOWA. 850MB TEMPERATURES THIS
MORNING SOUTH OF THIS BOUNDARY RANGE FROM +8C AT TOPEKA TO +11C AT
DODGE CITY WHILE NORTH OF THIS BOUNDARY RAPID CITY REPORTED -2C
AND ABERDEEN REPORTED -1C.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 112 AM CDT THU SEP 11 2014
SHORT TERM MODELS INDICATE AN UPPER LEVEL SHORTWAVE TROUGH DIGGING
SOUTHEAST ACROSS THE NORTHERN ROCKIES TODAY AND PUSHING FURTHER
SOUTHEAST INTO THE WESTERN HIGH PLAINS TONIGHT SETTING UP PRECIP
CHANCES ACROSS NEBRASKA SOUTHWARD INTO PORTIONS OF WESTERN KANSAS.
AS THE SHORTWAVE APPROACHES THIS EVENING, A SERIES OF H5 VORT MAXIMA
WILL BEGIN TO EJECT EASTWARD OUT OF THE COLORADO ROCKIES INTO THE
HIGH PLAINS OF EASTERN COLORADO AND WESTERN KANSAS. MEANWHILE, AN
ATTENDANT COLD FRONT TO THE SHORTWAVE WILL BEGIN TO PUSH SOUTHWARD
ACROSS WESTERN KANSAS LATE THIS EVENING INTO EARLY FRIDAY MORNING.
OVERNIGHT, DYNAMIC SUPPORT ALOFT WILL BECOME MORE FAVORABLE AS THE
RIGHT FRONT ENTRANCE REGION TO A +90KT JET EXITING THE APPROACHING
TROUGH AXIS SHIFTS SOUTHWARD INTO WESTERN KANSAS. AS A RESULT, RAIN
CHANCES WILL INCREASE ACROSS WESTERN KANSAS THIS EVENING, SPREADING
SOUTH AND EAST ACROSS THE REGION OVERNIGHT. A FEW ISOLATED
THUNDERSTORMS WILL BE POSSIBLE ACROSS EXTREME SOUTHWEST KANSAS THIS
EVENING WHERE SOME INCREASED INSTABILITY AND MORE FAVORABLE VERTICAL
SHEAR PROFILES WILL EXIST IN A SOUTHEASTERLY UPSLOPE FLOW. HOWEVER,
NAM/GFS MODEL SOUNDINGS INDICATE LIMITED INSTABILITY WITH CAPE
VALUES REMAINING WELL UNDER 1000 J/KG. THIS WILL RESTRICT THE
POTENTIAL FOR SEVERE STORMS ACROSS SOUTHWEST KANSAS.
TEMPERATURES WILL BE WELL BELOW NORMAL TODAY AS COOLER AIR FILTERS
SOUTHWARD INTO WESTERN KANSAS AHEAD OF A BROAD SURFACE HIGH MOVING
SOUTHEASTWARD OUT OF THE NORTHERN ROCKIES INTO THE HIGH PLAINS OF
EASTERN WYOMING AND WESTERN NEBRASKA. THE NAM AND GFS SHOW H85
TEMPERATURES FALLING BELOW 10C ACROSS CENTRAL KANSAS NEAR THE I-70
CORRIDOR BY THIS AFTERNOON WITH THE MID TO UPPER TEENS(C) ACROSS
EXTREME SOUTHWEST KANSAS WITHIN A SOUTHEAST UPSLOPE FLOW.
ADDITIONALLY, HIGH TEMPERATURES MAY BE HINDERED TODAY DEPENDING ON
HOW FAR SOUTH LOW LEVEL STRATUS MOVING OUT OF NEBRASKA THIS
MORNING PUSHES INTO SOUTHWEST KANSAS, NOT TO MENTION HOW LONG IT
MAY LAST. THE HRRR SUGGESTS THE STRATUS DECK PERSISTING THROUGH AT
LEAST MID DAY, PARTICULARLY ACROSS CENTRAL KANSAS IN THE VICINITY
OF THE I-70 CORRIDOR. BECAUSE OF THIS, HIGHS MAY STRUGGLE TO REACH
THE 60S(F) IN CENTRAL KANSAS WITH THE LOWER TO MID 70S(F) POSSIBLE
CLOSER TO THE OKLAHOMA BORDER, ESPECIALLY IN EXTREME SOUTHWEST
KANSAS. A SECONDARY PUSH OF COLDER AIR BEHIND YET ANOTHER COLD
FRONT PUSHING ACROSS WESTERN KANSAS EARLY FRIDAY MORNING WILL
LIKELY DROP LOWS DOWN INTO THE 40S(F) ACROSS MUCH OF CENTRAL AND
SOUTHWEST KANSAS TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 318 AM CDT THU SEP 11 2014
FRIDAY WILL BE COOL AND MOIST, WITH LIGHT RAIN LIKELY.
FRIDAY WILL BE IN A POST FRONTAL REGIME, WITH COOL HIGH PRESSURE
BUILDING IN FROM THE NORTHWEST. THE SURFACE FLOW WILL BE UPSLOPE
WITH NORTHEAST TO EASTERLY WINDS AT 10 TO 20 MPH. CLOUDS WILL BE
THICKEST IN THE MORNING, BUT STILL PREVALENT IN THE AFTERNOON. MAX
TEMPS WILL GENERALLY BE IN THE 50S, BUT I ONLY EXPECT LIGHT RAIN
WITH 0.05 TO 0.10 INCH ACCUMULATION. THE HIGH PRESSURE WILL BEGIN
TO DOMINATE FRIDAY EVENING, LEADING TO CLEAR SKIES OVERNIGHT. THE
COOL AIR WILL FILTRATE IN FROM THE NORTHWEST, AND FROST MAY BE
POSSIBLE IN OUR EXTREME NORTHWESTERN COUNTIES OF TREGO, AND
NORTHERN LANE AND SCOTT COUNTIES SATURDAY MORNING. AS THAT TIME
FRAME APPROACHES, WE WILL NEED TO LOOK INTO A POSSIBLE WATCH OR
REFINE THE AREA WHERE FROST MAY OCCUR.
AFTER THE FALL-LIKE WEATHER ON FRIDAY, SATURDAY AND SUNDAY WILL
SHOW A GRADUAL WARM UP, WITH HIGHS REACHING THE MID 60S TO LOWER
70S ON SATURDAY, AND BOUNDING UPWARD TO THE UPPER 70S TO LOWER 80S
BY SUNDAY. A COLD FRONT WILL PLOW THROUGH TO THE SOUTHEAST ON
MONDAY AFTERNOON, BRINGING A CHANCE FOR THUNDERSTORMS TO OUR
SOUTHEAST-MOST ZONES, PRIMARILY IN PRATT AND BARBER COUNTIES. AN
UPPER LEVEL WAVE WILL COME THROUGH IN THE FLOW MONDAY NIGHT,
GIVING MOST OF THE CWA A 20 TO 30 PERCENT CHANCE FOR
THUNDERSTORMS. A LEE SIDE TROUGH WILL BE IN WESTERN KANSAS TUESDAY
AND WEDNESDAY, AND SLIGHT CHANCES FOR SHOWERS AND ISOLATED
THUNDERSTORMS WILL EXIST ACROSS MOST OF OUR FORECAST AREA, MAINLY
THE EAST.
WEDNESDAY WILL SEE A RETURN TO A WARM SOUTHWEST FLOW, AND HIGH
TEMPERATURES WILL RESPOND LIKEWISE WITH VALUES IN THE LOWER 80S
NORTH OF I-70 AND THE MIDDLE 80S SOUTHWEST A LINE FROM GARDEN CITY
TO DODGE CITY TO MEDICINE LODGE. WINDS THROUGH THE EXTENDED DO NOT
LOOK TOO STRONG, EXCEPT AHEAD OF THE FRONT ON MONDAY, AND THEN
AGAIN BEHIND THE FRONT ON TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1208 PM CDT THU SEP 11 2014
BUFR SOUNDINGS AND HRRR BOTH IN GOOD AGREEMENT WITH IFR AND LIFR
CEILINGS GRADUALLY IMPROVING THROUGH THE EARLY AFTERNOON WITH A
BRIEF PERIOD OF VFR CONDITIONS DEVELOPING AT GCK AND DDC AFTER
21Z. CLOUD BASES WILL THEN LOWER ONCE AGAIN BACK INTO THE 700 TO
1500FT AGL LEVEL AFTER 00Z FRIDAY AS MORE HUMID AIR RETURNS TO
SOUTHWEST KANSAS. IN ADDITION TO THE LOWERING CEILINGS EARLY
TONIGHT PERIODS OF LIGHT RAIN AND/OR DRIZZLE CAN BE EXPECTED LATE
TONIGHT THROUGH EARLY FRIDAY. NORTHEASTERLY WINDS AT 15 TO 20
KNOTS THIS AFTERNOON WILL BECOME MORE NORTHERLY AFTER 06Z AND THEN
INCREASE TO 20 TO NEAR 25 KNOTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 60 45 53 40 / 0 90 80 0
GCK 59 42 50 38 / 10 90 80 0
EHA 69 45 51 43 / 20 90 90 0
LBL 65 48 54 42 / 10 90 80 0
HYS 58 42 52 38 / 10 90 80 0
P28 69 50 58 43 / 0 40 60 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BURGERT
SHORT TERM...JJOHNSON
LONG TERM...BURKE
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS JACKSON KY
354 PM EDT THU SEP 11 2014
.UPDATE...
ISSUED AT 142 PM EDT THU SEP 11 2014
CONSIDERING APPARENT FRONTAL POSITION AND PRECIP TRENDS...HAVE
LOWERED POPS FOR THIS AFTERNOON NORTH OF KJKL. ALSO...OBSERVED TEMPS
HAVE SURPASSED PREVIOUS FORECAST HIGHS IN OUR SOUTHERN COUNTIES. WITH
DEVELOPMENT OF PRECIP...IT SHOULD NOT GET TOO MUCH WARMER THERE...BUT
FORECAST MAX TEMPS DID NEED TO BE RAISED.
UPDATE ISSUED AT 1014 AM EDT THU SEP 11 2014
MADE ADJUSTMENTS TO TIMING OF SOUTHWARD PROGRESSION OF HIGHER POPS
TODAY...BUT WITH LITTLE IMPACT ON THE GENERAL 12 HOUR OUTLOOK.
UPDATE ISSUED AT 645 AM EDT THU SEP 11 2014
MADE A FEW ADJUSTMENTS TO THE FORECAST GRIDS FOR EARLY THIS MORNING
BASED ON THE CURRENT RADAR TRENDS. DECIDED TO SLIGHTLY SPEED UP THE
EASTWARD PROGRESSION OF SHOWERS AND STORMS THIS MORNING PER LATEST
RADAR. BASED ON UPSTREAM SHOWER AND STORM FORMATION...AND THE STILL
SLOW EASTWARD MOVEMENT OF THE COLD FRONT...IT STILL APPEARS THAT
WIDESPREAD RAINFALL WILL OCCUR ACROSS EASTERN KENTUCKY THROUGH THIS
AFTERNOON. LOCALLY HEAVY RAINFALL...AND PERHAPS SOME ISOLATED
INSTANCES OF FLOODING...WILL STILL BE POSSIBLE AS NUMEROUS STORMS
WILL LIKELY MOVE ACROSS THE SAME LOCATIONS THROUGHOUT THE DAY.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 323 AM EDT THU SEP 11 2014
THE MODELS WERE IN GOOD AGREEMENT WITH THE LARGE SCALE AND LOCAL
WEATHER PATTERN FOR THE FIRST 36 HOURS OF THE FORECAST. THE
NAM12...SREF...AND HRRR MODELS HAVE ALL HANDLED THE TIMING AND
EVOLUTION OF A LINE OF SHOWERS AND STORMS THAT IS CURRENTLY MOVING
ACROSS CENTRAL KENTUCKY AND SOUTHERN OHIO. THE NAM12 AND SREF SEEM TO
DO A BETTER JOB OF HANDLING THE EVOLUTION OF THIS LINE OF SHOWERS AND
STORMS AFTER SUNRISE TODAY THAN THE HRRR...SO THOSE TWO MODELS WERE
USED TO CREATE THE NEW FORECAST. THE MODELS SUGGEST A STRONG COLD
FRONT WILL MOVE ACROSS CENTRAL AND EASTERN KENTUCKY TODAY...WITH THE
BOUNDARY EXITING THE AREA LATE THIS AFTERNOON. WIDESPREAD SHOWERS AND
STORMS ARE EXPECTED TO CONTINUE FIRING ALONG AND JUST AHEAD OF THIS
FRONT...WITH THE PEAK IN ACTIVITY OCCURRING BETWEEN ROUGHLY NOON AND
5 PM. THE LATEST FORECAST SOUNDINGS CONTINUE TO SUPPORT THE POTENTIAL
FOR LOCALLY HEAVY RAINFALL...WITH PRECIPITABLE WATER VALUES OF AROUND
2 INCHES PERSISTING THROUGH THE OVERNIGHT HOURS. SOME OF THE STRONGER
THUNDERSTORMS COULD ALSO PRODUCE GUSTY WINDS...BUT LOCALLY HEAVY
RAINFALL WILL BE THE PRIMARY THREAT. THE RAIN CHANCES WILL NOT END
ONCE THE FRONT HAS PASSED BY US...HOWEVER. THE BOUNDARY IS EXPECTED
TO STALL ACROSS THE TENNESSEE VALLEY ON FRIDAY. WAVES OF LOW PRESSURE
ARE THEN PROGGED TO MIGRATE FROM WEST TO EAST ALONG THE FRONT. THESE
DISTURBANCES WILL BRING ENOUGH LIFT AND MOISTURE TO LOCATIONS SOUTH
OF THE MOUNTAIN PARKWAY TO PERHAPS FIRE OFF ISOLATED TO SCATTERED
RAIN SHOWERS LATE TONIGHT THROUGH THE END OF THE DAY ON FRIDAY.
ONCE THE FRONT MOVES THROUGH EARLY TONIGHT...AN UNSEASONABLY COOL
CANADIAN AIR MASS WILL SETTLE OVER THE AREA. THIS AIR MASS WILL BRING
FALL LIKE TEMPERATURES TO EASTERN KENTUCKY TONIGHT AND FRIDAY. THE
COOL WEATHER WILL FIRST BE EXPERIENCED LATE TONIGHT...AS WINDS SHIFT
TO THE NORTH AND THE COOL AIR FULLY INVADES THE REGION. TONIGHTS
LOWS ARE EXPECTED TO BOTTOM OUT IN THE LOW TO MID 60S FOR MOST
LOCATIONS. FOLKS ALONG AND NORTH OF THE I-64 CORRIDOR MAY SEE THE
MERCURY DIP INTO THE UPPER 50S BY FRIDAY MORNING. HIGH TEMPERATURES
ON FRIDAY WILL LIKELY ONLY CLIMB INTO THE LOW TO MID 70S ACROSS THE
AREA.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 354 PM EDT THU SEP 11 2014
MID TERM MODELS ARE STILL IN GOOD AGREEMENT FOR THE UPPER LEVEL LONG
WAVE PATTERN. A CLOSED LOW WILL BE PASSING ALONG THE UPPER GREAT
LAKES AT THE START OF THE FORECAST PERIOD...QUICKLY MOVING EASTWARD
AND LOSING STRENGTH. MEANWHILE...AN UPPER LEVEL RIDGE ACROSS THE
SOUTHERN CONUS WILL KEEP A GOOD TRANSITION ZONE OVER THE OHIO RIVER
VALLEY WITH STRONG WRLY FLOW. THIS SHORTWAVE/CLOSED LOW WILL CAUSE A
DISTURBANCE AT THE SURFACE...WITH A STRONG AREA OF QVECTOR
CONVERGENCE EXPECTED TO MOVE ACROSS THE UPPER GREAT LAKES REGION AS
WELL BY THE START OF THE FORECAST PERIOD. KY WILL FIND ITSELF ON THE
SOUTHERN FRINGES OF THIS DISTURBANCE...EXITING AS WE HEAD INTO 12Z
SATURDAY. AS IT QUICKLY PUSHES OFF TO THE EAST DURING THE DAY...ANY
PRECIP CHANCES WILL CEASE ACROSS FAR SE KY BY LATE SAT AFTERNOON.
MODELS ARE CONTINUING TO SUPPORT A FASTER EXIT OF PRECIPITATION
COMPARED TO THAT OF PREVIOUS RUNS FOR DURING THE DAY SATURDAY. CUT
BACK POPS SLIGHTLY...WITH ALL RAIN EXITING KY BY 0Z SUNDAY. THE
BOUNDARY WILL BECOME STALLED OUT ONCE MORE TO OUR SOUTH...NEAR THE
ATLANTIC COAST. HOWEVER...WITH THE INFLUX OF MOISTURE FROM THE
ATLANTIC...DAYTIME INSTABILITY WILL HELP PRECIP CHANCES SPREAD
FARTHER NORTH...POSSIBLY MAKING IT TO THE FAR SE BORDER OF KY DURING
THE DAY SUNDAY. PREVIOUS FORECAST LEFT MENTION OF PRECIP OUT
ALONG THE BORDER. HOWEVER...LATEST MODEL RUNS ARE ALL IN VERY
GOOD AGREEMENT THAT POPS MOVE CLOSE ENOUGH TO OUR BORDER THAT
CONFIDENCE ERRED ON THE SIDE AT LEAST INCLUDING SOME SLIGHT CHANCE
POPS FOR THE HIGH TERRAIN ALONG THE TN/VA BORDER. THE SAME APPLIES
FOR DURING THE DAY MONDAY....ALTHOUGH MODELS ARE GOOD AGREEMENT OF
THE PRECIP SPREADING FARTHER INTO THE CWA DURING THE DAY AS THE
BOUNDARY SHIFTS SLIGHTLY NORTHWARD.
MEANWHILE MONDAY...ANOTHER SHORTWAVE WILL DEVELOP IN THE LONGWAVE
PATTERN...DROPPING HEIGHTS SLIGHTLY ACROSS EASTERN KY AND BRINGING
YET ANOTHER QUICK MOVING BUT WEAK SURFACE COLD FRONT THAT WILL SWEEP
THROUGH KY LATE MONDAY NIGHT. ONCE AGAIN...ERN KY WILL FIND ITSELF
ON THE SOUTHERN FRINGES OF THIS DISTURBANCE...BUT THE BOUNDARY
SHOULD INTERACT ENOUGH WITH THE ONGOING PRECIP IN THE SE TO KEEP
POPS GOING THROUGHOUT MOST OF THE NIGHT MONDAY NIGHT AS WELL. STRONG
SUBSIDENCE WILL MOVE IN BEHIND THE FRONTAL BOUNDARY...WITH POPS
QUICKLY TAPERING OFF BY EARLY TUESDAY. WIDESPREAD CLOUD COVER WILL
ALSO ACCOMPANY THIS SYSTEM...SLOWLY CLEARING THROUGHOUT THE DAY
TUESDAY. HIGH PRESSURE...ONCE IN CONTROL...SHOULD STAY FOR THE
REMAINDER OF THE FORECAST PERIOD...WITH EASTERN KY FINALLY EXPECTED
TO HAVE A BREAK FROM THE PRECIP FROM TUESDAY THROUGH THURSDAY.
OVERALL...STRONG ZONAL FLOW ACROSS KY WILL KEEP TEMPERATURES
MODERATED IN THE MID 70S THROUGH MUCH OF THE EXTENDED FORECAST.
OVERNIGHT LOWS WILL BE CLOUD DEPENDENT. FOR THOSE NIGHTS WHEN
CLEARING IS EXPECTED...LOWS COULD DROP DOWN INTO THE CHILLY LOW TO
MID 50S. AND WHEN THERE IS CLOUD COVER INVOLVED...AS IS THE CASE IN
THE SE FOR MUCH OF THE EXTENDED...UPPER 50S AND LOW 60S WILL BE
RANGE TO LOOK FOR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1255 PM EDT THU SEP 11 2014
EARLY AFTERNOON CONDITIONS RANGED FROM VLIFR IN MANY LOCATIONS NEAR
AND NORTH OF I-64...TO VFR IN MOST PLACES NEAR THE TN AND VA BORDERS.
SHOWERS WERE OCCURRING AND BECOMING MORE NUMEROUS ALONG AND SOUTHEAST
OF A LINE FROM SOMERSET TO PAINTSVILLE.
DURING THE AFTERNOON...THE TREND OF INCREASING PRECIP SOUTH AND EAST
OF KJKL SHOULD CONTINUE...WITH A SLIGHT CHANCE FOR THUNDERSTORMS TOO.
MVFR AND IFR WILL SPREAD/DEVELOP SOUTHEASTWARD TO THE STATE LINE BY
ABOUT 00Z. MEANWHILE LOCATIONS NEAR/NORTH OF I-64 SHOULD SEE
IMPROVEMENT...WITH CEILINGS EVENTUALLY BREAKING UP TONIGHT AND
FRIDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...AR
LONG TERM...JMW
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS JACKSON KY
142 PM EDT THU SEP 11 2014
.UPDATE...
ISSUED AT 142 PM EDT THU SEP 11 2014
CONSIDERING APPARENT FRONTAL POSITION AND PRECIP TRENDS...HAVE
LOWERED POPS FOR THIS AFTERNOON NORTH OF KJKL. ALSO...OBSERVED TEMPS
HAVE SURPASSED PREVIOUS FORECAST HIGHS IN OUR SOUTHERN COUNTIES. WITH
DEVELOPMENT OF PRECIP...IT SHOULD NOT GET TOO MUCH WARMER THERE...BUT
FORECAST MAX TEMPS DID NEED TO BE RAISED.
UPDATE ISSUED AT 1014 AM EDT THU SEP 11 2014
MADE ADJUSTMENTS TO TIMING OF SOUTHWARD PROGRESSION OF HIGHER POPS
TODAY...BUT WITH LITTLE IMPACT ON THE GENERAL 12 HOUR OUTLOOK.
UPDATE ISSUED AT 645 AM EDT THU SEP 11 2014
MADE A FEW ADJUSTMENTS TO THE FORECAST GRIDS FOR EARLY THIS MORNING
BASED ON THE CURRENT RADAR TRENDS. DECIDED TO SLIGHTLY SPEED UP THE
EASTWARD PROGRESSION OF SHOWERS AND STORMS THIS MORNING PER LATEST
RADAR. BASED ON UPSTREAM SHOWER AND STORM FORMATION...AND THE STILL
SLOW EASTWARD MOVEMENT OF THE COLD FRONT...IT STILL APPEARS THAT
WIDESPREAD RAINFALL WILL OCCUR ACROSS EASTERN KENTUCKY THROUGH THIS
AFTERNOON. LOCALLY HEAVY RAINFALL...AND PERHAPS SOME ISOLATED
INSTANCES OF FLOODING...WILL STILL BE POSSIBLE AS NUMEROUS STORMS
WILL LIKELY MOVE ACROSS THE SAME LOCATIONS THROUGHOUT THE DAY.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 323 AM EDT THU SEP 11 2014
THE MODELS WERE IN GOOD AGREEMENT WITH THE LARGE SCALE AND LOCAL
WEATHER PATTERN FOR THE FIRST 36 HOURS OF THE FORECAST. THE
NAM12...SREF...AND HRRR MODELS HAVE ALL HANDLED THE TIMING AND
EVOLUTION OF A LINE OF SHOWERS AND STORMS THAT IS CURRENTLY MOVING
ACROSS CENTRAL KENTUCKY AND SOUTHERN OHIO. THE NAM12 AND SREF SEEM TO
DO A BETTER JOB OF HANDLING THE EVOLUTION OF THIS LINE OF SHOWERS AND
STORMS AFTER SUNRISE TODAY THAN THE HRRR...SO THOSE TWO MODELS WERE
USED TO CREATE THE NEW FORECAST. THE MODELS SUGGEST A STRONG COLD
FRONT WILL MOVE ACROSS CENTRAL AND EASTERN KENTUCKY TODAY...WITH THE
BOUNDARY EXITING THE AREA LATE THIS AFTERNOON. WIDESPREAD SHOWERS AND
STORMS ARE EXPECTED TO CONTINUE FIRING ALONG AND JUST AHEAD OF THIS
FRONT...WITH THE PEAK IN ACTIVITY OCCURRING BETWEEN ROUGHLY NOON AND
5 PM. THE LATEST FORECAST SOUNDINGS CONTINUE TO SUPPORT THE POTENTIAL
FOR LOCALLY HEAVY RAINFALL...WITH PRECIPITABLE WATER VALUES OF AROUND
2 INCHES PERSISTING THROUGH THE OVERNIGHT HOURS. SOME OF THE STRONGER
THUNDERSTORMS COULD ALSO PRODUCE GUSTY WINDS...BUT LOCALLY HEAVY
RAINFALL WILL BE THE PRIMARY THREAT. THE RAIN CHANCES WILL NOT END
ONCE THE FRONT HAS PASSED BY US...HOWEVER. THE BOUNDARY IS EXPECTED
TO STALL ACROSS THE TENNESSEE VALLEY ON FRIDAY. WAVES OF LOW PRESSURE
ARE THEN PROGGED TO MIGRATE FROM WEST TO EAST ALONG THE FRONT. THESE
DISTURBANCES WILL BRING ENOUGH LIFT AND MOISTURE TO LOCATIONS SOUTH
OF THE MOUNTAIN PARKWAY TO PERHAPS FIRE OFF ISOLATED TO SCATTERED
RAIN SHOWERS LATE TONIGHT THROUGH THE END OF THE DAY ON FRIDAY.
ONCE THE FRONT MOVES THROUGH EARLY TONIGHT...AN UNSEASONABLY COOL
CANADIAN AIR MASS WILL SETTLE OVER THE AREA. THIS AIR MASS WILL BRING
FALL LIKE TEMPERATURES TO EASTERN KENTUCKY TONIGHT AND FRIDAY. THE
COOL WEATHER WILL FIRST BE EXPERIENCED LATE TONIGHT...AS WINDS SHIFT
TO THE NORTH AND THE COOL AIR FULLY INVADES THE REGION. TONIGHTS
LOWS ARE EXPECTED TO BOTTOM OUT IN THE LOW TO MID 60S FOR MOST
LOCATIONS. FOLKS ALONG AND NORTH OF THE I-64 CORRIDOR MAY SEE THE
MERCURY DIP INTO THE UPPER 50S BY FRIDAY MORNING. HIGH TEMPERATURES
ON FRIDAY WILL LIKELY ONLY CLIMB INTO THE LOW TO MID 70S ACROSS THE
AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 431 AM EDT THU SEP 11 2014
THE MODELS ARE IN GOOD AGREEMENT WITH THE LONG WAVE PATTERN THROUGH
THE PERIOD. PROGRESSIVE AND AMPLIFIED FLOW WILL CONTROL ACROSS THE
NORTHERN HALF OF THE CONUS AS SEVERAL PASSING SHORT WAVES HELP TO
REINFORCE TROUGHING ACROSS THE REGION. UPPER LEVEL RIDGING HANGING ON
ACROSS THE SOUTHERN CONUS WILL GRADUALLY DAMPEN AND GET SUPPRESSED
FURTHER SOUTH INTO EARLY NEXT WEEK...BEFORE CONSOLIDATING MORE ACROSS
THE DESERT SOUTHWEST BY THE MIDDLE OF NEXT WEEK.
FOR EASTERN KENTUCKY...THE FIRST MAIN SHORT WAVE WILL MOVE THROUGH
FRIDAY NIGHT INTO SATURDAY...BRINGING A CHANCE OF SHOWERS. GENERALLY
DRY WEATHER CAN BE EXPECTED FROM SATURDAY NIGHT THROUGH SUNDAY
NIGHT...AS HIGH PRESSURE TEMPORARILY BUILDS IN AT THE SURFACE. A
DEEPER TROUGH AXIS...WITH SOME SURFACE DEVELOPMENT NOTED BY THE
MODELS...WILL THEN AFFECT THE AREA FROM MONDAY THROUGH
TUESDAY. THIS SYSTEM WILL BRING SOME RENEWED CHANCES OF
SHOWERS...ALTHOUGH THERE WILL NOT BE AS MUCH LOW LEVEL MOISTURE TO
WORK WITH...SO STUCK FAIRLY CLOSE TO THE BLENDED GUIDANCE ON THE
POPS. DRY WEATHER WILL ENSUE ONCE AGAIN THEREAFTER...AS SURFACE HIGH
PRESSURE BUILDS IN ACROSS THE OHIO VALLEY.
TEMPERATURES WILL AVERAGE BELOW NORMAL THROUGH THE PERIOD...WITH
HIGHS MAINLY IN THE LOW TO MID 70S AND LOWS IN THE 50S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1255 PM EDT THU SEP 11 2014
EARLY AFTERNOON CONDITIONS RANGED FROM VLIFR IN MANY LOCATIONS NEAR
AND NORTH OF I-64...TO VFR IN MOST PLACES NEAR THE TN AND VA BORDERS.
SHOWERS WERE OCCURRING AND BECOMING MORE NUMEROUS ALONG AND SOUTHEAST
OF A LINE FROM SOMERSET TO PAINTSVILLE.
DURING THE AFTERNOON...THE TREND OF INCREASING PRECIP SOUTH AND EAST
OF KJKL SHOULD CONTINUE...WITH A SLIGHT CHANCE FOR THUNDERSTORMS TOO.
MVFR AND IFR WILL SPREAD/DEVELOP SOUTHEASTWARD TO THE STATE LINE BY
ABOUT 00Z. MEANWHILE LOCATIONS NEAR/NORTH OF I-64 SHOULD SEE
IMPROVEMENT...WITH CEILINGS EVENTUALLY BREAKING UP TONIGHT AND
FRIDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...AR
LONG TERM...GEOGERIAN
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS JACKSON KY
1255 PM EDT THU SEP 11 2014
.UPDATE...
ISSUED AT 1014 AM EDT THU SEP 11 2014
MADE ADJUSTMENTS TO TIMING OF SOUTHWARD PROGRESSION OF HIGHER POPS
TODAY...BUT WITH LITTLE IMPACT ON THE GENERAL 12 HOUR OUTLOOK.
UPDATE ISSUED AT 645 AM EDT THU SEP 11 2014
MADE A FEW ADJUSTMENTS TO THE FORECAST GRIDS FOR EARLY THIS MORNING
BASED ON THE CURRENT RADAR TRENDS. DECIDED TO SLIGHTLY SPEED UP THE
EASTWARD PROGRESSION OF SHOWERS AND STORMS THIS MORNING PER LATEST
RADAR. BASED ON UPSTREAM SHOWER AND STORM FORMATION...AND THE STILL
SLOW EASTWARD MOVEMENT OF THE COLD FRONT...IT STILL APPEARS THAT
WIDESPREAD RAINFALL WILL OCCUR ACROSS EASTERN KENTUCKY THROUGH THIS
AFTERNOON. LOCALLY HEAVY RAINFALL...AND PERHAPS SOME ISOLATED
INSTANCES OF FLOODING...WILL STILL BE POSSIBLE AS NUMEROUS STORMS
WILL LIKELY MOVE ACROSS THE SAME LOCATIONS THROUGHOUT THE DAY.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 323 AM EDT THU SEP 11 2014
THE MODELS WERE IN GOOD AGREEMENT WITH THE LARGE SCALE AND LOCAL
WEATHER PATTERN FOR THE FIRST 36 HOURS OF THE FORECAST. THE
NAM12...SREF...AND HRRR MODELS HAVE ALL HANDLED THE TIMING AND
EVOLUTION OF A LINE OF SHOWERS AND STORMS THAT IS CURRENTLY MOVING
ACROSS CENTRAL KENTUCKY AND SOUTHERN OHIO. THE NAM12 AND SREF SEEM TO
DO A BETTER JOB OF HANDLING THE EVOLUTION OF THIS LINE OF SHOWERS AND
STORMS AFTER SUNRISE TODAY THAN THE HRRR...SO THOSE TWO MODELS WERE
USED TO CREATE THE NEW FORECAST. THE MODELS SUGGEST A STRONG COLD
FRONT WILL MOVE ACROSS CENTRAL AND EASTERN KENTUCKY TODAY...WITH THE
BOUNDARY EXITING THE AREA LATE THIS AFTERNOON. WIDESPREAD SHOWERS AND
STORMS ARE EXPECTED TO CONTINUE FIRING ALONG AND JUST AHEAD OF THIS
FRONT...WITH THE PEAK IN ACTIVITY OCCURRING BETWEEN ROUGHLY NOON AND
5 PM. THE LATEST FORECAST SOUNDINGS CONTINUE TO SUPPORT THE POTENTIAL
FOR LOCALLY HEAVY RAINFALL...WITH PRECIPITABLE WATER VALUES OF AROUND
2 INCHES PERSISTING THROUGH THE OVERNIGHT HOURS. SOME OF THE STRONGER
THUNDERSTORMS COULD ALSO PRODUCE GUSTY WINDS...BUT LOCALLY HEAVY
RAINFALL WILL BE THE PRIMARY THREAT. THE RAIN CHANCES WILL NOT END
ONCE THE FRONT HAS PASSED BY US...HOWEVER. THE BOUNDARY IS EXPECTED
TO STALL ACROSS THE TENNESSEE VALLEY ON FRIDAY. WAVES OF LOW PRESSURE
ARE THEN PROGGED TO MIGRATE FROM WEST TO EAST ALONG THE FRONT. THESE
DISTURBANCES WILL BRING ENOUGH LIFT AND MOISTURE TO LOCATIONS SOUTH
OF THE MOUNTAIN PARKWAY TO PERHAPS FIRE OFF ISOLATED TO SCATTERED
RAIN SHOWERS LATE TONIGHT THROUGH THE END OF THE DAY ON FRIDAY.
ONCE THE FRONT MOVES THROUGH EARLY TONIGHT...AN UNSEASONABLY COOL
CANADIAN AIR MASS WILL SETTLE OVER THE AREA. THIS AIR MASS WILL BRING
FALL LIKE TEMPERATURES TO EASTERN KENTUCKY TONIGHT AND FRIDAY. THE
COOL WEATHER WILL FIRST BE EXPERIENCED LATE TONIGHT...AS WINDS SHIFT
TO THE NORTH AND THE COOL AIR FULLY INVADES THE REGION. TONIGHTS
LOWS ARE EXPECTED TO BOTTOM OUT IN THE LOW TO MID 60S FOR MOST
LOCATIONS. FOLKS ALONG AND NORTH OF THE I-64 CORRIDOR MAY SEE THE
MERCURY DIP INTO THE UPPER 50S BY FRIDAY MORNING. HIGH TEMPERATURES
ON FRIDAY WILL LIKELY ONLY CLIMB INTO THE LOW TO MID 70S ACROSS THE
AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 431 AM EDT THU SEP 11 2014
THE MODELS ARE IN GOOD AGREEMENT WITH THE LONG WAVE PATTERN THROUGH
THE PERIOD. PROGRESSIVE AND AMPLIFIED FLOW WILL CONTROL ACROSS THE
NORTHERN HALF OF THE CONUS AS SEVERAL PASSING SHORT WAVES HELP TO
REINFORCE TROUGHING ACROSS THE REGION. UPPER LEVEL RIDGING HANGING ON
ACROSS THE SOUTHERN CONUS WILL GRADUALLY DAMPEN AND GET SUPPRESSED
FURTHER SOUTH INTO EARLY NEXT WEEK...BEFORE CONSOLIDATING MORE ACROSS
THE DESERT SOUTHWEST BY THE MIDDLE OF NEXT WEEK.
FOR EASTERN KENTUCKY...THE FIRST MAIN SHORT WAVE WILL MOVE THROUGH
FRIDAY NIGHT INTO SATURDAY...BRINGING A CHANCE OF SHOWERS. GENERALLY
DRY WEATHER CAN BE EXPECTED FROM SATURDAY NIGHT THROUGH SUNDAY
NIGHT...AS HIGH PRESSURE TEMPORARILY BUILDS IN AT THE SURFACE. A
DEEPER TROUGH AXIS...WITH SOME SURFACE DEVELOPMENT NOTED BY THE
MODELS...WILL THEN AFFECT THE AREA FROM MONDAY THROUGH
TUESDAY. THIS SYSTEM WILL BRING SOME RENEWED CHANCES OF
SHOWERS...ALTHOUGH THERE WILL NOT BE AS MUCH LOW LEVEL MOISTURE TO
WORK WITH...SO STUCK FAIRLY CLOSE TO THE BLENDED GUIDANCE ON THE
POPS. DRY WEATHER WILL ENSUE ONCE AGAIN THEREAFTER...AS SURFACE HIGH
PRESSURE BUILDS IN ACROSS THE OHIO VALLEY.
TEMPERATURES WILL AVERAGE BELOW NORMAL THROUGH THE PERIOD...WITH
HIGHS MAINLY IN THE LOW TO MID 70S AND LOWS IN THE 50S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1255 PM EDT THU SEP 11 2014
EARLY AFTERNOON CONDITIONS RANGED FROM VLIFR IN MANY LOCATIONS NEAR
AND NORTH OF I-64...TO VFR IN MOST PLACES NEAR THE TN AND VA BORDERS.
SHOWERS WERE OCCURRING AND BECOMING MORE NUMEROUS ALONG AND SOUTHEAST
OF A LINE FROM SOMERSET TO PAINTSVILLE.
DURING THE AFTERNOON...THE TREND OF INCREASING PRECIP SOUTH AND EAST
OF KJKL SHOULD CONTINUE...WITH A SLIGHT CHANCE FOR THUNDERSTORMS TOO.
MVFR AND IFR WILL SPREAD/DEVELOP SOUTHEASTWARD TO THE STATE LINE BY
ABOUT 00Z. MEANWHILE LOCATIONS NEAR/NORTH OF I-64 SHOULD SEE
IMPROVEMENT...WITH CEILINGS EVENTUALLY BREAKING UP TONIGHT AND
FRIDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...AR
LONG TERM...GEOGERIAN
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1245 PM CDT THU SEP 11 2014
.AVIATION...
COLD FRONT IS WRAPPING THE OUACHITAS AND DEEP CONVECTION REMAINS
NORTH OF I-30 WITH AN OUTFLOW FROM AR INTO I-20 OF LA DVLPG SMALL
CONVECTIVE ELEMENTS. HRRR MODEL SHOWING INCREASING COVERAGE AND
INTENSITY ALONG I-20 INTO THE HEAT OF THE AFTERNOON. VCTS FOR MANY
CITES WITH AMENDMENTS TO COME AS THE THREAT UNFOLDS. SFC WINDS
LIGHT SW AND SHIFTING TO N BEHIND OUTFLOW FOR KTXK/KELD AND SOON
FOR KSHV. ALOFT...SHV VAD...LOW LEVEL VEERING FROM SW THIS AM TO NW
THIS EARLY PM. FROPA WILL BE DURING THIS CYCLE WITH NE SFC WINDS.
&&
.PREV DISCUSSION... /ISSUED 931 AM CDT THU SEP 11 2014/
UPDATE...
HAVE UPDATED THE FORECAST TO MENTION HEAVY RAINFALL POSSIBLE IN
THE AREAS ALONG AND NEAR THE I-30 CORRIDOR. WPC HAS OUTLOOKED THE
AREA FOR HEAVY RAINFALL AND FLASH FLOODING LIKELY...NEW FORECAST
IS ALREADY OUT...
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 93 73 88 65 83 / 40 40 50 30 20
MLU 95 72 88 65 86 / 40 30 50 40 20
DEQ 84 68 77 60 77 / 60 50 70 20 10
TXK 90 71 81 63 80 / 60 50 60 30 10
ELD 91 70 86 63 81 / 40 40 60 30 20
TYR 91 73 86 64 82 / 40 50 50 20 20
GGG 94 73 88 64 82 / 40 40 50 30 20
LFK 95 74 89 69 83 / 20 30 50 40 30
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
24
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
359 PM EDT THU SEP 11 2014
.SYNOPSIS...
COLD FRONT WILL CROSS THE REGION THIS EVENING AND INTO THE
OVERNIGHT. THE FRONT WILL STALL OVER NORTH CAROLINA THROUGH THE
WEEKEND. FRONTAL BOUNDARY WILL REMAIN ALONG THE SOUTHEAST COAST
INTO EARLY NEXT WEEK AS HIGH PRESSURE BUILDS TO THE NORTH.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
LATEST RADAR MOSAIC DEPICTS A NARROW BAND OF
SHOWERS/THUNDERSTORMS OVER THE HIGHER TERRAIN OF WRN VA. COLD
FRONT LOCATED NOT FAR BEHIND OVER THE CNTRL APPALACHIANS. ISOLATED
SHOWERS HAVE DEVELOPED JUST WEST OF THE LOCAL AREA...BUT QUICKLY
DISSIPATED AS THEY PROPAGATED EWD THANKS TO SUBSIDENCE ALOFT.
EXPECT THIS TREND TO CONTINUE UNTIL THE COLD FRONT REACHES THE
LOCAL AREA LATE THIS AFTERNOON-EARLY THIS EVENING.
WEAK UPPER WAVE VISIBLE ON WATER VAPOR WILL PUSH INTO THE REGION
THIS EVENING AS THE COLD FRONT SLOWLY CROSSES THE LOCAL AREA.
PRECIP CHANCES THIS EVENING WILL BE TIED TO THE WEAKENING
FRONT/CONVERGENCE ZONE. SHORTWAVE WILL HELP SUPPORT SOME MODEST
UVM...BUT WITH THE BEST DYNAMICS/FLOW REMAINING WELL NORTH...UPPER
LEVEL FORCING WILL BE RATHER UNIMPRESSIVE. HI-RES GUIDANCE
CONTINUES TO INDICATE SCT SHOWERS/THUNDERSTORMS ALONG/IN ADVANCE
OF THE FRONT WITH THE BEST COVERAGE OVER THE N AND NE. SOME
LOCATIONS IN THE SW COULD EVEN REMAIN DRY. UPSTREAM PWATS AROUND 2
INCHES WILL SPREAD INTO THE REGION IN WLY FLOW...WITH MOISTURE
EXTENDING UP TO 300MB. UNFAVORABLE OVERNIGHT FRONTAL TIMING AND
WEAK SHEAR WILL ONLY RESULT IN SLIGHT CHANCE-CHANCE THUNDER.
POTENTIAL EXISTS OVER THE PIEDMONT FOR GUSTY WINDS AS TIMING AND
INSTABILITY IS BETTER AND BUFR SOUNDINGS INDICATED DRY LOW LEVELS.
LOCALLY HEAVY RAINFALL IS ALSO POSSIBLE DUE TO HIGH PWATS AND WEAK
FLOW. FRONTAL TIMING AND CLOUDS WILL RESULT IN MILD OVERNIGHT
TEMPS...GENERALLY IN THE MID-UPPER 60S. COOLER IN THE NW IF SKIES
CAN CLEAR BEHIND THE FRONT.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
UNSETTLED/WET WEATHER PATTERN EXPECTED THROUGH THE WEEKEND AS
TEMPS REMAIN BELOW NORMAL.
COLD FRONT PUSHES THRU THE AREA THRU FRI MORNING...STALLING
ACROSS NC AS FLOW ALOFT REMAINS SWLY. A POTENT UPPER SHORTWAVE
OVER THE UPPER MIDWEST WILL EJECT QUICKLY EWD AS A STRONG SPEED
MAX ROUNDS THE BASE OF THE TROUGH. SUBTROPICAL HIGH GETS SHOVED
SWD OVER THE GULF STATES/NRN GULF...BUT VERY LITTLE CHANGE IN MID
LEVEL HEIGHTS OVER THE LOCAL AREAL. SFC HIGH PRESSURE BUILDS OVER
SE CANADA/NE US WITH A RIDGE AXIS EXTENDING SWD INTO THE LOCAL
AREA. STILL SOME UNCERTAINTY AS TO WHERE THE FRONT WILL
STALL...BUT ATTM IT APPEARS IT WILL BE JUST SOUTH OF THE LOCAL
AREA. BEST CHANCES FOR MEASURABLE RAIN WILL BE TIED TO THE WEAK
FRONTAL BOUNDARY AND HIGH PWAT AXIS. HOWEVER...MDLS DIFFER ON THE
AMOUNT OF MOISTURE OVER THE LOCAL AREA...WHICH COMBINED WITH WEAK
WAVES IN SWLY FLOW MAY BE ENOUGH FOR SHOWERS FRI. WILL KEEP BETTER
POPS CLOSE TO THE FRONT...BUT WILL MAINTAIN LOW END CHANCE POPS
NWD INTO CNTRL VA. HYBRID WEDGE SETUP WILL KEEP SKIES CLOUDY AS
WINDS WILL BE FROM THE N-NE. CLOUDS/POSSIBLE PRECIP WILL PREVENT
TEMPS FROM REACHING THEIR FULL POTENTIAL WITH HIGHS GENERALLY IN
THE MID 70S.
SHORTWAVE PROPAGATES EWD OVER THE GREAT LAKES INTO SE CANADA SAT.
A WAVE OF LOW PRESSURE IS PROGGED TO DEVELOP ALONG THE FRONT OVER
THE TN VALLEY WITH ANOTHER AREA OF LOW PRESSURE DEVELOPING OFF THE
NC COAST. THE INLAND LOW WILL BEGIN TO LIFT NEWD IN AMPLIFYING
FLOW...LIFTING THE FRONT NWD. TWO DISTINCT AREAS OF PRECIP
EXPECTED TO DEVELOP FRI NIGHT-SAT MORNING...WITH THE FIRST LIFTING
OVER THE CNTRL APPALACHIANS AND THE OTHER REMAINING OVER ERN NC
AND OFFSHORE. BUT AS THE LOW QUICKLY LIFTS NWD INTO NEW
ENGLAND...OVERRUNNING MOISTURE/PRECIP OVERSPREAD MUCH OF THE LOCAL
AREA FROM THE SOUTH AND WEST. HAVE INCREASED POPS TO LIKELY AS
BETTER AGREEMENT IN THE MODELS LENDS TO HIGHER CONFIDENCE. PWATS
RETURN TO AROUND 2+ INCHES...AND MOISTURE EXTENDS WELL ABOVE
0C...SO LOCALLY HEAVY RAINFALL IS POSSIBLE. SHORTWAVE PUSHES OFF
THE NE COAST SAT NIGHT INTO SUN MORNING AS THE COASTAL LOW LIFTS
NEWD AWAY FROM THE COAST. HOWEVER...FLOW REMAINS SWLY OVER THE
LOCAL AREA WITH THE BOUNDARY REMAINING ALONG THE COAST. HIGH
PRESSURE WILL ALSO BUILD OVER NEW ENGLAND IN WAKE OF LOW
PRESSURE...REINFORCING THE HYBRID CAD OVER THE LOCAL AREA. NLY
FLOW WILL AGAIN RESULT IN MOSTLY CLOUDY-CLOUDY SKIES. INLAND BUFR
SOUNDINGS INDICATE SOME CLEARING OVER THE PIEDMONT. BEST RAINFALL
CHANCES TRANSITION TO ERN VA SAT NIGHT INTO SUN WITH THE BEST
CHANCES FOR PRECIP TRANSFERRING TO SE VA/NE NC SUN. TRENDED QPF
TOWARD ENSEMBLE MEAN GUIDANCE...WITH QPF AMOUNTS THIS WEEKEND
RANGING FROM AROUND ONE QUARTER INCH NE TO AN INCH SOUTH.
HOWEVER...THERE ARE SOME OUTLIERS INDICATING THAT MORE RAINFALL
MAY FALL. BASED ON PWATS OF +2 STD DEV AND WEAK FLOW...LOCALLY
HEAVY RAINFALL IS EXPECTED WITH SOME AREAS RECEIVING UPWARDS OF 2+
INCHES. HIGHS AGAIN SUN IN THE LOW-MID 70S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
DESPITE THE TIME OF THE YEAR...WILL LEAN TOWARD THE WETTER ECMWF
GIVEN THE FORECASTED UPR LVL PATTERN NEXT WEEK. FRONTAL BOUNDARY
REMAINS SOUTH OF THE REGION TO START OFF THE PERIOD WITH SEVERAL
AREAS OF LOW PRESSURE MOVING NORTH ALONG IT MONDAY AND TUESDAY
BASICALLY KEEPING CLOUDS AND PERIODIC CHCS FOR RAIN. FRONTAL BNDRY
MAY ACTUALLY SNAKE BACK NORTH AS A WARM FRONT TUESDAY SO WENT AHEAD
AND ADDED THUNDER ACROSS SERN HALF OF FA THEN. CLOUDS / PCPN KEEPS
TMPS BLO NORMAL WITH HIGHS BOTH DAYS IN THE 70S. LOWS U50S-U60S.
TRAILING COLD FRONT PUSHES OFFSHORE TUES NIGHT AND ERLY WED AS THE
1020MB CANADIAN HIGH PRS BUILDS EAST. GUID WANTS TO STALL THIS BNDRY
IVOF THE GULF STREAM ONCE AGAIN KEEPING ADDNTL CLOUDINESS AND SCT
SHWRS ALONG THE MID ATLNTC COASTAL SECTIONS WED INTO THU. COOLER
WITH HIGH WED / THU 70-75. LOWS IN THE 50S XCPT 60S COASTAL AREAS.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
VFR CONDITIONS PREVAIL AHEAD OF A COLD FRONT. THE FRONT WILL MOVE
ACROSS THE AREA THIS EVENING. ACCOMPANYING THE FRONT WILL BE
SCATTERED SHOWERS AND TSTMS. SEVERAL MODELS WEAKEN THESE STORMS AS
THE CROSS THE AREA TONIGHT. THE HRRR TRIES TO BRING SOME THROUGH
AFTER 00Z TO ABOUT 03Z. WOULD EXPECT AT LEAST SOME SHOWERS THAT
TIME FRAME AND POSSIBLY A TSTM. THE HEAVIEST SHOWERS COULD BRIEFLY
BRING MVFR CIGS OR VSBY. AFTER THE FRONT PASSES WINDS WILL SHIFT
TO THE NORTHEAST. WINDS ALOFT WILL REMAIN SOUTHWEST AND CAUSE THE
FRONT TO STALL IN NORTHEAST NORTH CAROLINA. THIS WILL CAUSE CLOUDS
TO LINGER ACROSS THE AREA LATE TONIGHT AND THROUGH FRIDAY. THERE
IS A GOOD CHANCE FOR MVFR CIGS FROM PHF SOUTHEAST. COULD EVEN BE
SOME BRIEF IFR CIGS ON FRIDAY MORNING. THERE WILL ALSO BE THE
CHANCE OF SHOWERS AGAIN ON FRIDAY.
OUTLOOK...THE FRONT REMAINS STATIONARY IN NE NC WITH WEAK WAVES
OF LOW PRESSURE MOVING ALONG IT INTO THE WEEKEND. THIS WILL CAUSE
PERIODS OF PCPN AND POSSIBLE MVFR AND PATCHY IFR SATURDAY THROUGH
SUNDAY.
&&
.MARINE...
MODELS CONTINUE TO SHOW A SEVERAL HOUR PERIOD OF MINIMAL SCA WINDS
BEHIND A COLD FRONT LATE TONIGHT AND FRI. TWEEKED TIMING OF SCA`S
FOR THE BAY A BIT AND ALSO ADDED THE LOWER JAMES RIVER TO THE MIX
FRI MORNING. WENT AHEAD WITH A MINIMAL SCA FOR NRN CSTL WTRS FRI
MORNING AS WELL. DATA SUGGESTS GUSTS TO 25 KTS PSBL N OF PARRAMORE
ISLAND FOR A FEW HRS. SEAS AVGG 3-4 FT BUT CAN`T RULE OUT SOME 5
FOOTERS OUT NEAR 20 NM AT TIMES.
HIGH PRES MOVES INTO NEW ENG BY SAT...BRINGING CONTD ONSHORE (NE)
WNDS AHEAD OF NEXT LOW PRES SYS AND ITS ASSOCIATED CDFNT. THAT SYS
CROSSES THE WTRS SAT NIGHT. MODELS NOT AS BULLISH WITH THE SURGE
BEHIND THIS BNDRY...BUT WILL CONTINUE TO INDICATE ANTHR CAA SURGE
SUN MORNING GIVEN THE MODELS TEND TO UNDERFCST THESE EVENTS.
ONSHORE FLOW CONTINUES INTO EARLY NEXT WEEK BUT SPEEDS XPCTD TO
REMAIN BLO 20 KTS AS A COMPLEX SYSTEM OF LOW PRESSURE SYSTMS AFFECT
THE MID ATLNTC REGION.
&&
.TIDES/COASTAL FLOODING...
GIVEN A FORECAST OF LEVELS RIGHT ARND MINOR FLOODING THRESHOLDS
FOR THIS AFTRNS HIGH TIDE...WENT AHEAD AND ISSUED ANTHR CSTL FLOOD
ADVSRY FOR THE CHES BAY SIDE OF THE LWR MD ERN SHORE BTWN 18Z-00Z.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
MDZ025.
COASTAL FLOOD ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
MDZ021>023.
NC...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
NCZ102.
VA...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
VAZ098>100.
MARINE...SMALL CRAFT ADVISORY FROM 7 AM TO 4 PM EDT FRIDAY FOR ANZ632-
634.
SMALL CRAFT ADVISORY FROM 6 AM TO NOON EDT FRIDAY FOR ANZ630-
631.
SMALL CRAFT ADVISORY FROM 6 AM TO 1 PM EDT FRIDAY FOR ANZ638.
SMALL CRAFT ADVISORY FROM 6 AM TO 2 PM EDT FRIDAY FOR ANZ650-
652.
&&
$$
SYNOPSIS...SAM
NEAR TERM...SAM
SHORT TERM...SAM
LONG TERM...MPR
AVIATION...LSA/JAB
MARINE...MPR
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
134 PM EDT THU SEP 11 2014
.SYNOPSIS...
A COLD FRONT OVER THE OHIO VALLEY WILL APPROACH THE MID ATLANTIC
STATES AND MOVE THROUGH THE AREA TONIGHT AND SETTLE OVER NORTH
CAROLINA FRIDAY. A LOW PRESSURE SYSTEM WILL AFFECT THE REGION
SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE HAS PUSHED OFFSHORE THIS MORNING IN ADVANCE OF A
COLD FRONT APPROACHING FROM THE WEST. GRADIENT BTWN THESE SFC
FEATURES HAS PRODUCED SW WINDS OF 10 TO 15 MPH WITH A FEW GUSTS OF
25 MPH. MORNING STRATUS HAS ERODED WITH ONLY SOME PASSING HIGH
CLOUDS RESULTING IN PARTLY SUNNY SKIES. TEMPS HAVE ALREADY WARMED
INTO THE UPPER 70S TO LOW 80S THANKS TO SW WINDS AND INCREASING
THICKNESSES.
FOR TODAY...WATER VAPOR AND MORNING RAOB PLOTS INDICATE SHORTWAVE
ENERGY OVER THE LWR MO VALLEY THAT WILL TRACK EWD ALONG THE KY/TN
VALLEYS THRU THE DAY. COLD FRONT WILL REACH THE CNTRL APPALACHIANS
EARLY THIS EVENING. IN ADVANCE OF THE FRONT...STRONG SFC HEATING
AND SW WINDS (GUSTS TO 20 MPH) WILL PUSH TEMPS INTO THE LOW 90S
(+1 STD DEV) MOST LOCATIONS. LOW-MID 80S ALONG THE COAST. HIGH
PRESSURE ALOFT WILL NUDGE INTO THE REGION FROM THE SW
TODAY...HELPING PROVIDE SUBSIDENCE OVER THE REGION. LACK OF
APPRECIABLE FORCING/TRIGGER WILL ALSO HELP KEEP THINGS
DRY...REGARDLESS OF INCREASING MOISTURE/INSTABILITY AND POTENTIAL
HEATING/DIFFERENTIAL BOUNDARIES. MAINLY FAIR WEATHER CU TODAY
UNDER THE INVERSION...WITH MID-HIGH CLOUDS INCREASING FROM THE
WEST LATE TODAY.
PRECIP CHANCES WILL BE TIED TO THE WEAKENING FRONT/CONVERGENCE
ZONE. AFOREMENTIONED SHORTWAVE WILL LIKELY HELP SUPPLY SOME MODEST
UVM...BUT WITH THE BEST DYNAMICS/FLOW REMAINING WELL NORTH...UPPER
LEVEL FORCING WILL BE RATHER UNIMPRESSIVE. EVEN ONGOING PRECIP
OVER THE CNTRL APPALACHIANS WILL QUICKLY OUTRUN THE BETTER UPPER
LEVEL SUPPORT...LIKELY DISSIPATING AS IT REACHES THE PIEDMONT.
PRECIP CHANCES INCREASE LATE TODAY INTO THIS EVENING ACROSS THE
PIEDMONT. HI-RES GUIDANCE CONTINUES TO INDICATE SCT
SHOWERS/THUNDERSTORMS ALONG THE LINE WITH THE BEST COVERAGE OVER
THE N AND NE. SOME LOCATIONS IN THE SW COULD REMAIN DRY. UPSTREAM
PWATS AROUND 2 INCHES WILL SPREAD INTO THE REGION IN WLY
FLOW...WITH MOISTURE EXTENDING UP TO 300MB. UNFAVORABLE OVERNIGHT
FRONTAL TIMING AND WEAK SHEAR WILL ONLY RESULT IN SLIGHT CHANCE
THUNDER. POTENTIAL EXISTS OVER THE PIEDMONT FOR GUSTY WINDS AS
TIMING AND INSTABILITY IS BETTER AND BUFR SOUNDINGS INDICATED DRY
LOW LEVELS. LOCALLY HEAVY RAINFALL IS ALSO POSSIBLE DUE TO HIGH
PWATS AND WEAK FLOW. FRONTAL TIMING AND CLOUDS WILL RESULT IN MILD
OVERNIGHT TEMPS...GENERALLY IN THE MID-UPPER 60S. COOLER IN THE NW
IF SKIES CAN CLEAR BEHIND THE FRONT.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
FRIDAY WILL SEE SIGNIFICANTLY COOLER TEMPERATURES DUE TO CLOUD COVER
AND A COOLER AIR MASS. PCPN WILL BE MAINLY OVER SE PORTIONS CLOSE TO
THE FRONT WITH POPS LOWERING THROUGH THE DAY FROM NORTH TO SOUTH.
FUTURE ISSUANCES MAY BE ABLE TO HAVE ADDITIONAL LOWERING OF THE POPS
NORTHERN PORTIONS. LOWERED TEMPERATURES FRIDAY WITH GENERALLY LOW TO
MID 70S EXCEPT UPR 70S TO NEAR 80 IN NORTH CAROLINA COUNTIES. CLOUD
COVER WILL RESULT IN LOW TEMPERATURES FROM THE MID 60S TO AROUND 70
SATURDAY MORNING.
AN UPPER LEVEL SHORT WAVE MOVES ACROSS THE MIDWEST AND DEVELOPS A
SURFACE LOW TO OUR WEST. THIS WILL BRING AN INCREASE IN MOISTURE AND
PCPN DURING THE DAY SATURDAY. BASICALLY HAVE 50 PERCENT POPS ACROSS
THE AREA AS THE DETAILS ARE NOT CLEAR AT THIS POINT. FUTURE
ISSUANCES WILL PROBABLY HAVE LIKELY POPS IN PORTIONS OF THE CWA.
CLOUD COVER AND PCPN WILL HOLD TEMPERATURES DOWN AND HAVE HIGHS JUST
A FEW DEGREES HIGHER THAN FRIDAY...GENERALLY MID TO UPR 70S WITH 80
DEGREE READINGS IN NORTH CAROLINA.
MINOR CHANGES WERE MADE TO THE FORECAST FOR SATURDAY NIGHT AND
SUNDAY BUT GENERALLY DRYING MOVES IN FROM THE NW FOLLOWING THE
PASSAGE OF THE SHORT WAVE. ANOTHER DAY OF BELOW NORMAL TEMPERATURES
IS EXPECTED ON SUNDAY. SEE BELOW FOR MORE DETAILS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
UPR LEVEL TROF ACROSS THE ERN US RESULTS IN A COOLER THAN NORMAL
PATTERN THROUGH THE MEDIUM RANGE PERIOD. MODELS SEEM TO AGREE THAT
THE FA WILL BE NORTH OF THE STALLED FRONTAL BOUNDARY (IVOF THE GULF
STREAM) EARLY NEXT WEEK. THE FORECAST CHALLENGE WILL BE TIMING OF
SEVERAL WAVES OF ENERGY PROGGED TO MOVE NE ALONG THIS BOUNDARY AS
CANADIAN HIGH PRESSURE (1025 MB) TRACKS EAST WHILE REMAINING NORTH
OF THE AREA.
FOLLOWED THE ECMWF WRT SYNOPTIC FEATURES WHICH FEATURES A SCNDRY
BNDRY PASSAGE SAT NIGHT / SUNDAY. KEPT CHC POPS (SHWRS) IN ATTM WITH
THE HIGHEST POPS ACROSS SRN HALF OF FA...ESPECIALLY SUNDAY. MAY
ACTUALLY DRY ACROSS NRN COUNTIES WITH SOME AFTRN SUNSHINE GIVEN
STRENGTH OF THE HIGH PRESSURE BUILDING IN FROM THE NW. LOWS SAT &
SUN NIGHTS 55-60 NORTH...M-U60S SOUTH. HIGHS SUN L-M70S.
DATA SUGGESTS BOUNDARY BEGINS TO DRIFT BACK NORTH AS A WARM FRONT
MON AND TUES...BUT CONFIDENCE ON JUST HOW FAR NORTH IT GETS IS
PROBLEMATIC ATTM. KEPT CHC POPS (SHWRS...KEEPING THUNDER OUT OF FCST
THIS FAR OUT) WITH HIGHEST POPS SOUTH ONCE AGAIN. HIGHS MON L-M70S.
LOWS MON NIGHT U50S-U60S. WARMING A BIT TUESDAY WITH HIGHS 75-80.
DRYING OUT WED WITH HIGHS M-U70S.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
VFR CONDITIONS PREVAIL AHEAD OF A COLD FRONT. THE FRONT WILL MOVE
ACROSS THE AREA THIS EVENING. ACCOMPANYING THE FRONT WILL BE
SCATTERED SHOWERS AND TSTMS. SEVERAL MODELS WEAKEN THESE STORMS AS
THE CROSS THE AREA TONIGHT. THE HRRR TRIES TO BRING SOME THROUGH
AFTER 00Z TO ABOUT 03Z. WOULD EXPECT AT LEAST SOME SHOWERS THAT
TIME FRAME AND POSSIBLY A TSTM. THE HEAVIEST SHOWERS COULD BRIEFLY
BRING MVFR CIGS OR VSBY. AFTER THE FRONT PASSES WINDS WILL SHIFT
TO THE NORTHEAST. WINDS ALOFT WILL REMAIN SOUTHWEST AND CAUSE THE
FRONT TO STALL IN NORTHEAST NORTH CAROLINA. THIS WILL CAUSE CLOUDS
TO LINGER ACROSS THE AREA LATE TONIGHT AND THROUGH FRIDAY. THERE
IS A GOOD CHANCE FOR MVFR CIGS FROM PHF SOUTHEAST. COULD EVEN BE
SOME BRIEF IFR CIGS ON FRIDAY MORNING. THERE WILL ALSO BE THE
CHANCE OF SHOWERS AGAIN ON FRIDAY.
OUTLOOK...THE FRONT REMAINS STATIONARY IN NE NC WITH WEAK WAVES
OF LOW PRESSURE MOVING ALONG IT INTO THE WEEKEND. THIS WILL CAUSE
PERIODS OF PCPN AND POSSIBLE MVFR AND PATCHY IFR SATURDAY THROUGH
SUNDAY.
&&
.MARINE...
SSW WNDS AHEAD OF APPROACHING CDFNT FM THE W THROUGH TDA. A BIT OF A
NOCTURNAL SURGE (TO ABT 15 KT) INVOF CNTRL BAY INTO EARLY THIS MRNG.
OTRW...CONDS RMN BLO SCA INTO TNGT. CDFNT CROSSES THE WTRS AFT
MIDNIGHT THROUGH MID MRNG FRI. XPCG A POST FNTL SURGE IN SPEEDS FM
THE N (TO LO END SCA ON THE BAY)...THERE MAY BE A SHORT PD OF SCAS
ON THE (NRN) OCN WATERS IN THE EARLY/MID MRNG AS WELL. IT IS TIME OF
YEAR FOR THESE TYPES OF SURGES TO BE A BIT MORE ROBUST THAN MDLS
FCST (COOLER/DRIER AIR SPREADING OVR WARMER WTRS). THE INCRS IN SPDS
DIMINISHES FM N TO S OVR THE WTRS IN THE AFTN/EVE HRS. SFC HI PRES
MOVES INTO NEW ENG BY SAT...BRINGING CONTD ONSHORE WNDS AHEAD OF
NEXT APPROACHES LO PRES SYS AND ITS ASSOCIATED CDFNT. THAT SYS
CROSSES THE WTRS SAT EVE...W/ PTNTLLY AN EVEN STRONGER NLY SURGE IN
ITS WAKE INTO SUN.
&&
.TIDES/COASTAL FLOODING...
GIVEN A FORECAST OF LEVELS RIGHT ARND MINOR FLOODING THRESHOLDS
FOR THIS AFTRNS HIGH TIDE...WENT AHEAD AND ISSUED ANTHR CSTL FLOOD
ADVSRY FOR THE CHES BAY SIDE OF THE LWR MD ERN SHORE BTWN 18Z-00Z.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
MDZ025.
COASTAL FLOOD ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
MDZ021>023.
NC...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
NCZ102.
VA...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
VAZ098>100.
MARINE...SMALL CRAFT ADVISORY FROM 7 AM TO 3 PM EDT FRIDAY FOR ANZ632-
634.
SMALL CRAFT ADVISORY FROM 6 AM TO NOON EDT FRIDAY FOR ANZ630-
631.
&&
$$
SYNOPSIS...LSA
NEAR TERM...SAM
SHORT TERM...LSA
LONG TERM...MPR
AVIATION...LSA/JAB
MARINE...ALB
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
255 PM CDT Thu Sep 11 2014
.SHORT TERM: (Through Late Tonight)
Issued at 252 PM CDT Thu Sep 11 2014
Clouds have not cleared out this afternoon even though high
pressure has begun to build into the low levels. This is because
of persistent low level inversion that the RAP is showing around
900mb. Moisture is being trapped below this inversion, so expect
these clouds to persist into the night. Drizzle may redevelop over
the area toward morning. Temperatures did not climb much today and
do not have far to fall tonight to reach agreeable MOS guidance
for lows.
Britt
.LONG TERM: (Friday through Next Thursday)
Issued at 252 PM CDT Thu Sep 11 2014
Next shortwave to continue sliding southeast into forecast area on
Friday. Models in good agreement on timing and precipitation
associated with it. Will see isolated/widely scattered showers
develop and spread southeast across forecast area during the day
on Friday exiting late Friday evening. QPF amounts will be rather
light with best chances along and north of I-70. As for
temperatures, to remain well below normal with highs only in the
upper 50s to upper 60s. Lows Friday night will be in the low 40s
to low 50s.
Then on Saturday, strong ridge of high pressure to build in and
skies to clear out. Despite the sunshine, it will continue to feel
like fall with high temperatures only in the 60s and lows Saturday
night in the 40s.
By Sunday, surface ridge begins to move off to the east allowing
temperatures to slowly moderate. Highs will be in the upper 60s to
low 70s. Then Sunday night the next weather system to approach the
region with showers developing and spread southeast through region
Sunday night through Monday night. Frontal boundary to stall out
just south of forecast area early Tuesday morning with weak surface
ridging building in. Could see some lingering isolated/scattered
showers through Wednesday night for western and southern portions of
the area. As for temperatures, highs will be in the 70s and lows in
the 50s through next Thursday.
Byrd
&&
.AVIATION: (For the 18z TAFs through 18z Friday Afternoon)
Issued at 1226 PM CDT Thu Sep 11 2014
Expect mainly MVFR conditions to persist through the rest of the
TAF period. Current ceilings are expected to improve to above 2000
feet this afternoon, though the are expected to remain below 3000
feet through the night. Ceilings are expected to fall below 2000
feet with some IFR conditions possible between 08-16Z as drizzle
redevelops at the terminals. Conditions will then improve again by
mid morning Friday. Winds will be north to northeast and and
remain under 10kts.
Specifics for KSTL: Expect MVFR ceilings to persist through the
period, with bases increasing above 2000ft this afternoon.
Ceilings will fall back below 2000ft between 09-15Z with -dz
redeveloping at the terminal. Improvement is then expected after
mid morning Friday.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1227 PM CDT Thu Sep 11 2014
.UPDATE:
Issued at 1059 AM CDT Thu Sep 11 2014
Mainly cloudy skies are expected the rest of the afternoon. The
latest RAP soundings are showing moisture being trapped below a
inversion at 900mb. This will keep temperatures from climbing much
this afternoon given the clouds and northerly winds. Fewer locations
are reporting drizzle this last hour, so I expect this trend
should continue into the afternoon as the ceilings increase.
Britt
&&
.SHORT TERM: (Through Late This Afternoon)
Issued at 340 AM CDT Thu Sep 11 2014
A strong surface cold front has moved completely southeast of our
region early this morning with an extensive area of low clouds in
its wake. The radar mosaic showed the northern edge of the rain was
barely edging our region into southern Reynolds and Madison counties
in MO. The center of the airmass responsible for this cold front
was still well to the northwest of us over southern Alberta province
meaning this airmass will take considerable time to build into our
area and remain around for awhile. Temps have dipped into the 50s
for many areas north of Interstate 70, but remain in the 60s and
even lower 70s elsewhere.
A strong storm system at the upper levels will dig in across Montana
and Wyoming today and actually back the flow across our region to a
bit more southwesterly than what it is currently. This should cause
the surface front to become quasi-stationary, but still remain well
to our south. However, the better moisture in tow behind the front
will likely remain across much of southeastern MO and far southern
IL thru today. Models loosely depict a wave riding along the
stalling frontal boundary later today--more specifically late this
morning and early this afternoon--which looks to be a sufficiently
northern enough track to justify some mentionable PoP throughout a
good portion of the day in the far southern CWA in southeastern MO.
Otherwise, the atmosphere drys out enough to go with a dry forecast.
Based on PIREPs from last evening, the thickness of the cloud layer
currently over us is about 2500ft. We are less than two weeks from
the autumnal equinox and with a rather persistently decent CAA at
the low levels expected, expect this low cloud to be a bit of a
foretaste to the more stubborn cloud cover we will encounter more
frequently during the colder months. Favored a more pessimistic
cloud cover forecast a la the RAP which doesn`t really start to
break things up until later this afternoon and even then may re-gel
together tonight.
Cloudy skies for much of the day will keep temps down and this looks
like it is well handled with the 00z MOS, with maxes in the 60s.
TES
.LONG TERM: (Tonight through Wednesday)
Issued at 340 AM CDT Thu Sep 11 2014
The shortwave now diving into Montana will move into the northeast
Plains and Upper Midwest Friday. Latest guidance is in good
agreement with the speed and track of the wave as it passes north of
the area. Most of the synoptic scale lift ahead of the shortwave
will pass north of the CWFA, but we will be in the right rear
quadrant of the upper level jet and both the GFS and NAM are also
showing bands of frontogenetical forcing moving through Friday
afternoon and Friday night. Corresponding light QPF is being
produced by the models, so feel pretty confident there will be some
light rain. However am not sure how much of this precip will be
measurable so am sticking with slight chance to mid chance PoPs
Friday afternoon through Friday night as this wave moves through.
Zonal flow aloft with a 1030mb Canadian high pressure will control
the weather for the weekend. Expect this to provide the Bi-State
region with spectacular weather for those who enjoy Autumn, with
highs mainly in the mid 60s to low 70s and lows in the 40s.
Medium range guidance is indicating a pattern shift in the
atmosphere over us toward mid-week from quasi-zonal to northwest
flow aloft. The initial wave which will dig into the eastern CONUS
is forecast to pass over the Midwest Monday into Monday night. Much
like Friday`s wave, the broad synoptic lift associated with the wave
should pass north of us with a band of low level frontogenetical
forcing ahead of another cold front. Feel low chance PoPs continue
to be indicated for Monday and Monday night as this forcing affects
the region, and higher PoPs may be needed if the shortwave turns out
to be stronger than currently forecast. Another shot of Canadian
air will shift across the Midwest Tuesday into the Ohio Valley
Wednesday. Stuck close to guidance for temperatures with highs in
the 70s and lows in the 50s which continue to be below
climatology...although it may not be cool enough given the falling
heights and easterly flow as the high moves east of the area.
Carney
&&
.AVIATION: (For the 18z TAFs through 18z Friday Afternoon)
Issued at 1226 PM CDT Thu Sep 11 2014
Expect mainly MVFR conditions to persist through the rest of the
TAF period. Current ceilings are expected to improve to above 2000
feet this afternoon, though the are expected to remain below 3000
feet through the night. Ceilings are expected to fall below 2000
feet with some IFR conditions possible between 08-16Z as drizzle
redevelops at the terminals. Conditions will then improve again by
mid morning Friday. Winds will be north to northeast and and
remain under 10kts.
Specifics for KSTL: Expect MVFR ceilings to persist through the
period, with bases increasing above 2000ft this afternoon.
Ceilings will fall back below 2000ft between 09-15Z with -dz
redeveloping at the terminal. Improvement is then expected after
mid morning Friday.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
132 PM EDT THU SEP 11 2014
.SYNOPSIS...
LATE SUMMER WEATHER CAN BE EXPECTED TODAY AHEAD OF A COLD FRONT
APPROACHING FROM THE NORTHWEST. THE FRONT WILL BRING AN INCREASING
CHANCE OF SHOWERS AND STORMS FRIDAY THROUGH MONDAY. A SERIES OF
CANADIAN HIGH PRESSURE SYSTEMS WILL BUILD INTO THE REGION A GOOD
PORTION OF NEXT WEEK...BRINGING A FEEL OF EARLY FALL TO THE AREA.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1045 AM THURSDAY...TRIMMED MAXIMUM TEMPERATURES A DEGREE OR
2 ACROSS THE CAPE FEAR REGION DUE TO HIGH LAYERED BUT IMPACTFUL
CLOUDS PRESENTLY SAILING SOUTH OVER A SWATH OF PENDER AND NEW
HANOVER COUNTIES. OTHERWISE LITTLE CHANGE TO EXPECTED HIGHS TODAY
AND THIS IS SHAPING UP TO BE OUR WARMEST DAY IN A WHILE AND FOR A
WHILE...AS A COLD EDGES CLOSER TO THE REGION FROM THE NORTHWEST.
STRONG INSOLATION WILL CERTAINLY PROMPT CUMULUS DEVELOPMENT THIS
AFTERNOON...AND SATELLITE BASED PWAT DETECTORS ARE REGISTERING
INCREASING COLUMN MOISTURE OVER THE AREA IN THE INCREASINGLY WARM
PRE-FRONTAL AIR MASS HERE LOCALLY. THUS WITH DEWPOINT EXPECTATIONS
COUPLED WITH MAX T TODAY WILL RESULT IN MAX APPARENT TEMPERATURES
IN THE 90S MOST AREAS.
THE OTHER CHANGE WAS TO REMOVE MENTIONABLE POP VALUES FOR THE
DAYTIME PERIOD TODAY AS IT APPEARS DRY AIR WILL REMAIN IN PLACE
ABOVE 9-10KFT. WHILE A RAINDROP CANNOT BE RULED OUT COMPLETELY
ALONG THE MAXIMUM OF SEA BREEZE CONVERGENCE...AM BASING POPS ON
MEASURABLE RAINFALL PROBABILITY...AND THIS IS LESS THAN 15 PCNT
THROUGH AFTERNOON. LAND VS SEA TEMPERATURE DIFFERENTIAL SHOULD
PROPEL A HEALTHY SEA BREEZE CIRCULATION BY THE MIDDLE/LATE AFTN.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 300 AM THURSDAY...COLD FRONT WILL MOVE ACROSS THE CAROLINAS
ON FRIDAY WITH INCREASING CLOUDS AND CHC OF SHWRS/TSTMS THROUGH
THE DAY. THE FRONT WILL SLOW DOWN AND STALL OUT IN THE VICINITY OF
LOCAL FORECAST AREA AS SHORTWAVE PUSHING THIS FRONT COMES UP
AGAINST A DECENT RIDGE IN PLACE ACROSS THE SOUTHEAST AND RIDES UP
TO THE NORTHEAST...LEAVING A FLOW MORE PARALLEL TO FRONT. THE NEXT
SHORTWAVE SHOULD NUDGE THE FRONT A LITTLE FARTHER SOUTH SAT NIGHT
BUT LOOKS LIKE IT MAY STILL REMAIN STRETCHED JUST ALONG THE
SOUTHEAST COAST. LATEST GFS RUN WAS A LITTLE FASTER...MOVING THE
FRONT INTO THE CAPE FEAR REGION BY FRI AFTERNOON. THE MAIN
SHORTWAVE ENERGY WILL REMAIN WELL NORTH OF AREA BUT CONVERGENCE
ALONG THE COLD FRONT ALONG WITH A SATURATED COLUMN WILL PRODUCE SOME
HIGHER END QPF AMOUNTS OVER FORECAST AREA. THE PCP WATER VALUES
REACH ABOVE 2.25 INCHES WITH BULLSEYE OVER LOCAL FORECAST AREA BY
FRI AFTN AND REMAINING ABOVE 2 INCHES THROUGH THE WEEKEND. OVERALL
EXPECT A CLOUDY AND WET FORECAST FOR THE WEEKEND. TEMPS OVER
SOUTHEAST NORTH CAROLINA WILL MAKE A RUN FOR 80 DEGREES ON FRIDAY
BEFORE FRONT MOVES IN WHILE TEMPS IN NORTHEAST SOUTH CAROLINA
SHOULD MAKE IT INTO THE MID 80S. CLOUDS...SHOWERS AND LIGHT
NORTHERLY FLOW WILL KEEP TEMPS BELOW NORMAL FOR HIGHS AND ABOVE
NORMAL FOR OVERNIGHT LOWS FRIDAY AND SATURDAY.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 300 AM THURSDAY...SHORTWAVES RIDING AROUND BROAD TROUGH OVER
THE GREAT LAKES WILL PUSH PERSISTENT RIDGE OVER THE SOUTHERN CONUS
A LITTLE FARTHER SOUTH THROUGH EARLY NEXT WEEK. THE COLD FRONT
CAUGHT IN BETWEEN WILL REMAIN HUNG UP IN THE VICINITY PRODUCING
PLENTY OF CLOUDS AND UNSETTLED WEATHER THROUGH MUCH OF THE WEEK.
WILL KEEP CLOUDS AND CHC POPS IN FORECAST THROUGH AT LEAST TUES.
THE BROAD MID TO UPPER TROUGH OVER THE GREAT LAKES WILL DIG
FARTHER SOUTH THROUGH TUES AND MAY PUSH FAR ENOUGH SOUTH TO ALLOW
DRIER AIR TO MOVE IN. HIGH PRESSURE WILL BUILD DOWN INTO THE
SOUTHEAST BUT COLD FRONT WILL LINGER THROUGH THE WEEK...PERHAPS
REMAINING FAR ENOUGH SOUTH BY TUES TO ALLOW FOR SOME DRIER WEATHER
FOR MID WEEK. FOR NOW WILL KEEP CLOUDS AND PCP IN FORECAST AS
WINDS ALOFT OUT OF THE W-SW WILL RIDE OVER THE COOLER NORTHERLY
FLOW TO SUPPORT LIFT THROUGHOUT MUCH OF THE PERIOD. SHOULD END UP
WITH A DECENT QPF SPREAD OVER SEVERAL DAYS. THE COOLER NORTHERLY
FLOW ALONG WITH CLOUDS AND PCP WILL ALL COMBINE TO KEEP TEMPS
BELOW NORMAL MOST DAYS AND OVERNIGHT LOWS JUST ABOVE NORMAL.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 18Z...FRONTAL BOUNDARY SLOW APPROACHING THROUGH THE FORECAST
PERIOD. THE HRRR DOES DEPICT SOME ISOLATED CONVECTION ALONG THE SEA
BREEZE...VERY ISOLATED AND NOT ENOUGH FOR A MENTION IN THE TAFS.
SOUTHERLY FLOW ON THE EAST SIDE OF THE RESULTANT.
TONIGHT...INCREASING CLOUDINESS TOWARD MORNING AS THE FRONT
APPROACHES. IF WE DO NOT GET A CEILING SOON ENOUGH HOWEVER...SOME
FOG MAY FORM...POSSIBLY PRETTY DENSE. WILL GO WITH THE CEILING
SCENARIO FOR NOW WITH ONLY LIGHT FOG. FRIDAY...CONVECTION BREAKING
OUT FROM WEST TO EAST. THE LATEST NAM IS NOT SO ENTHUSED WITH ONLY
ISOLATED ACTIVITY ALONG THE COAST BY AFTERNOON.
EXTENDED OUTLOOK...INCREASING CHANCES FOR SHOWERS/TSTMS AND TEMPO
MVFR FRIDAY AFTERNOON THROUGH THE WEEKEND WITH AN APPROACHING COLD
FRONT. THE FRONT STALLS WITH A CONTINUED CHANCE FOR PRECIP THROUGH
TUESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1045 AM THURSDAY...SFC RIDGING FROM THE WESTERN ATLANTIC
HIGH...WILL PERSIST ACROSS AND AFFECT THE ILM COASTAL WATERS
THROUGH TONIGHT. THE SFC PRESSURE PATTERN WILL PRODUCE S-SW WIND
DIRECTIONS...THE SFC PRESSURE GRADIENT WILL REMAIN LOOSE INTO THIS
EVENING AND THUS PRODUCING AROUND 10 KT WIND SPEEDS. THE LOCAL SEA
BREEZE CIRCULATION WILL PROVIDE AN ADDITIONAL 5 KT THIS AFTERNOON
AND EARLY TONIGHT WITH 10-15 KT BECOMING COMMON ESPECIALLY
NEARSHORE OR WITHIN 10 NM OF THE COAST. FOR TONIGHT...THE COLD
FRONT DROPPING SE-WARD...WILL PUSH CLOSER TO THE AREA WATERS. THE
END RESULT WILL BE A SLIGHT TIGHTENING OF THE SFC PG. WILL
HIGHLIGHT WITH SW WINDS INCREASING TO 10-15 KT. SIGNIFICANT SEAS
WILL HOVER AROUND 2 FT...BUILDING TO 2 TO 3 FT THIS AFTN AND
TONIGHT DUE TO THE INCREASE OF LOW PERIOD WIND DRIVEN WAVES.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 300 AM THURSDAY...LIGHT SOUTHERLY FLOW AHEAD OF AN
APPROACHING COLD FRONT ON FRIDAY WILL COME AROUND TO THE N-NE BY
FRI NIGHT BUT WILL REMAIN FAIRLY LIGHT IN AN OTHERWISE WEAKER
GRADIENT FLOW. OVERALL EXPECT WINDS LESS THAN 10 KTS THROUGH MUCH
OF THE WEEKEND. THIS WILL KEEP SEAS LESS THAN 3 FT FOR THE MOST
PART ACROSS THE LOCAL WATERS.
LONG TERM /SUNDAY THROUGH MONDAY/...
AS OF 300 AM THURSDAY...A SLOW MOVING COLD FRONT SHOULD GET
ANOTHER NUDGE SOUTHWARD EARLY SUNDAY HELPING IT TO PROGRESS SOUTH
THROUGH EARLY NEXT WEEK...BUT GRADIENT WILL REMAIN RELAXED KEEPING
WINDS LESS THAN 10 KTS. SEAS WILL REMAIN LESS THAN 3 FT THROUGH
THE PERIOD.
&&
.TIDES/COASTAL FLOODING...
AS OF 1045 AM THURSDAY...LATEST TIDE FORECASTS FOR THE CAPE FEAR
RIVER GAGE IN THE VICINITY OF DOWNTOWN WILMINGTON IS EXPECTED TO
APPROACH 6.00 FT MLLW AROUND NOON TODAY. THIS IS NEARLY HALF A
FOOT ABOVE THE THRESHOLD FOR COASTAL FLOODING TO OCCUR. IN
ADDITION...WATER ACROSS CANAL DRIVE OF CAROLINA BEACH IS
CORRELATED TO THE CAPE FEAR RIVER GAGE REACHING NEAR 6.00 FT MLLW.
A CFW HAS BEEN ISSUED AND IS IN EFFECT BETWEEN 11AM AND 2PM AT
WHICH TIME GAGE READINGS WILL BE AT OR ABOVE 5.5 FT MLLW.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...COASTAL FLOOD ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR
NCZ107-108.
MARINE...NONE.
&&
$$
SYNOPSIS...MJC
NEAR TERM...MJC
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...DL/8
TIDES...DOUGH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1146 AM CDT THU SEP 11 2014
.UPDATE...
ISSUED AT 1146 AM CDT THU SEP 11 2014
SURFACE-BASED ISOLATED SHOWER ACTIVITY HAS ALREADY DEVELOPED OVER
CENTRAL NORTH DAKOTA IN THE AREAS WHERE MID/UPPER LEVEL CLOUDS
HAVE CLEARED OUT. IT LOOKS LIKE THE LATEST HRRR IS VERIFYING THE
AREAL COVERAGE OF ISOLATED SHOWER ACTIVITY. AS A RESULT...UPDATED
THE FORECAST REFLECT THE LATEST HRRR SOLUTION AND ADDED ISOLATED
SHOWERS OVER ALL OF WESTERN AND CENTRAL NORTH DAKOTA TO THE
AFTERNOON FORECAST. THE REMAINING FORECAST ELEMENTS ARE IN GOOD
SHAPE. THE UPDATED PRODUCTS WILL BE OUT SHORTLY.
UPDATE ISSUED AT 1006 AM CDT THU SEP 11 2014
CLOUDS ARE BEGINNING TO BREAK OVER WESTERN AND CENTRAL NORTH
DAKOTA. TEMPERATURES ARE RESPONDING BY JUMPING INTO THE 40S WITHIN
THE LAST HOUR. BOWMAN RADAR SHOWS ALL RETURNS SOUTH OF THE STATE.
HOWEVER...MAINTAINED CHANCE OF LIGHT RAIN SOUTHWEST THROUGH THE
THE MORNING AS A BAROCLINIC ZONE WILL BE IN THE VICINITY.
ELSEWHERE...THE LATEST ARW AND NMM MESOSCALE MODELS PROG ISOLATED
TO SCATTERED SHOWER ACTIVITY DEVELOPING SOUTHWEST OF THE MISSOURI
RIVER THIS AFTERNOON. THE LATEST HRRR PROGS ISOLATED SHOWERS
DEVELOPING CWA-WIDE THIS AFTERNOON. GIVEN THE PROXIMITY OF THE
MOISTURE AND SUBTLE MUCAPE...WILL KEEP AFTERNOON POPS CONFINED TO
AREAS SOUTHWEST OF THE MISSOURI RIVER...SIMILAR TO THE ARW AND NMM
SOLUTIONS. AS A RESULT...CHANGED AFTERNOON WEATHER PRECIP TYPE
WORDING FROM STRATIFORM RAIN TO CONVECTIVE SHOWERS. THE UPDATED
PRODUCTS WILL BE OUT SHORTLY.
UPDATE ISSUED AT 645 AM CDT THU SEP 11 2014
LATEST SATELLITE IMAGERY SHOWS UPPER LEVEL TROUGH DROPPING SOUTH
THROUGH THE NORTHERN ROCKIES WITH STRONG JET EXTENDING FROM THE
BASE OF THE TROUGH EAST INTO THE NORTHERN PLAINS. LATEST RADAR
IMAGERY INDICATES THE MAJORITY OF THE PRECIPITATION REMAINING
SOUTH OF THE FORECAST AREA...WITH FAR SOUTHWEST BOWMAN COUNTY
SEEING SOME LIGHT RETURNS. MADE SOME MINOR ADJUSTMENTS TO
POPS...CONFINING THEM TO THE FAR SOUTHWEST EARLY THIS MORNING. IF
WE SEE SOME BREAKS IN THE CLOUDS TODAY...STRONG LOW LEVEL LAPSE
RATES SHOULD AID IN SHOWER DEVELOPMENT FARTHER NORTH AND EAST.
LATEST HRRR DEVELOPS ISOLATED CONVECTION ACROSS THE CWA BY THIS
AFTERNOON. FOR NOW WILL KEEP POPS LIMITED TO THE SOUTHWEST QUARTER
AS PREVIOUSLY FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 346 AM CDT THU SEP 11 2014
FREEZING TEMPERATURES TONIGHT HIGHLIGHT THE SHORT TERM FORECAST.
THE 00 UTC DETERMINISTIC SUITE SUGGESTS THE CURRENT STRATUS DECK
IN PLACE THIS MORNING ACROSS WESTERN AND CENTRAL NORTH DAKOTA WILL
BEGIN TO CLEAR ACROSS THE FAR NORTH LATE THIS AFTERNOON. THE
CLEARING TREND IS FORECAST TO CONTINUE TO PUSH SOUTH THROUGH THE
EVENING AS THE SURFACE HIGH ACROSS WESTERN SASKATCHEWAN THIS
MORNING PROPAGATES INTO WESTERN SOUTH DAKOTA FRIDAY MORNING.
GIVEN COOL TEMPERATURES IN THE 40S AND LOWER 50S TO BEGIN THE
EVENING...WIDESPREAD LOWS IN THE UPPER 20S AND LOWER 30S ARE EXPECTED
ACROSS MUCH OF WESTERN AND CENTRAL NORTH DAKOTA TONIGHT WITH
RADIATIONAL COOLING. THUS HAVE ISSUED A FREEZE WARNING FOR MUCH OF
THE AREA LATE TONIGHT INTO FRIDAY MORNING..OUTSIDE OF THE JAMES
RIVER VALLEY AND FAR SOUTH CENTRAL. FOR THESE AREAS...SUFFICIENT
CLOUD COVER IS EXPECTED TO REMAIN THROUGH THE NIGHT TO KEEP LOWS
ABOVE FREEZING. HOWEVER...A FROST ADVISORY MAY BE NEEDED WITH
LATER UPDATES.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 346 AM CDT THU SEP 11 2014
A MEAN EASTERN PACIFIC/WESTERN U.S RIDGE AND CENTRAL/EASTERN U.S.
TROUGH PATTERN IS EXPECTED TO CONTINUE THROUGH THE LONG TERM PERIOD.
NORTHWEST FLOW OVER THE NORTHERN PLAINS WILL BRING A SERIES OF WEAK
SHORTWAVES DOWN THE LEE OF THE CANADIAN ROCKIES AND INTO THE
FORECAST AREA...KEEPING DAYTIME HIGH TEMPERATURES MAINLY IN THE
60S...WITH A THREAT OF PATCHY FROST EACH MORNING INTO EARLY NEXT
WEEK. THE WESTERN RIDGE FINALLY TRANSLATES INLAND NEXT WEEK BRINGING
UPPER LEVEL RIDGING AND WARMER TEMPERATURES...MAINLY 70S...TO THE
FORECAST AREA NEXT TUESDAY THROUGH THURSDAY. COULD SEE AN ISOLATED
SHOWER ALONG THE INTERNATIONAL BORDER SATURDAY EVENING...OTHERWISE
DRY CONDITIONS ARE ANTICIPATED THROUGH THE EXTENDED PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1146 AM CDT THU SEP 11 2014
ISOLATED SHOWERS WILL DEVELOP OVER WESTERN AND CENTRAL NORTH
DAKOTA THIS AFTERNOON. WILL ADD VCSH TO ALL TAF SITES AS A RESULT.
IMPACTS TO SPECIFIC TERMINAL AERODROMES SHOULD BE BRIEF...IF ANY
AT ALL. OTHERWISE...VFR CONDITIONS ARE EXPECTED THROUGH THE
REMAINDER OF THE TAF PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM 1 AM CDT /MIDNIGHT MDT/ TO 10 AM CDT /9 AM
MDT/ FRIDAY FOR NDZ001>005-009>013-017>022-031>035-040>044.
&&
$$
UPDATE...TM
SHORT TERM...AYD
LONG TERM...TWH
AVIATION...TM
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
401 PM EDT THU SEP 11 2014
.SYNOPSIS...
A STRONG COLD WILL MOVE ACROSS THE REGION TODAY. COOL AND DRIER
WEATHER WILL FOLLOW FOR FRIDAY. A NEW DISTURBANCE WILL MOVE
THROUGH THE AREA ON SATURDAY BEFORE HIGH PRESSURE RETURNS FAIR
WEATHER FOR SUNDAY. THE OVERALL PATTERN FAVORS BELOW NORMAL
TEMPERATURES FROM SATURDAY INTO NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
2PM UPDATE...
AS OF 2PM...THE COLD FRONT IS BETWEEN STATE COLLEGE AND ALTOONA
WITH EVEN FEWER SHOWERS ASSOCIATED THAN EARLIER THIS MORNING. THE
UPPER SHORTWAVE IS VERY FLAT AND SHEARED OUT...SO SUPPORT FOR THE
FRONT IS NOT IMPRESSIVE EVEN THOUGH THE AIRMASS DISCONTINUITY IS.
TEMPERATURES HAVE BEEN STEADY OR FALLING OVER NWRN PA ALL DAY
WHILE TEMPS HAVE RISEN INTO THE LOWER 80S OVER THE SERN PART OF
THE AREA.
THE RAP SHOWS VIRTUALLY NO CAPE OR LOW LEVEL CONVERGENCE ALONG
WITH WEAK MID LEVEL LAPSE RATES...AND THE LACK OF SHOWER ACTIVITY
PRETTY MUCH CONFIRMS THIS ANALYZED LACK OF INSTABILITY.
I LOWERED THE OVERALL PROBABILITY OF SHOWERS AND ISOLATED
THUNDERSTORMS OVER MY SERN ZONES AS THE FRONT SWEEPS EAST. THE
NEXT 3-6 HOURS WILL BE THE WINDOW OF BEST OPPORTUNITY FOR RAIN
BEFORE THINGS DRY OUT FOR TONIGHT AND FRIDAY.
THE FRONT WILL PUSH SE OF THE AREA THIS EVENING WITH AN
INITIALLY GUSTY NW FLOW GIVING WAY TO A LIGHTER BREEZE. MODEL
SOUNDINGS SHOW A FAIR AMOUNT OF LOW LEVEL MOISTURE BEING TRAPPED
UNDER A STRENGTHENING SUBSIDENCE INVERSION. LOOKS LIKE LOW CLOUDS
AND EVEN SOME PATCHY FOG WILL REDEVELOP LATER TONIGHT...LASTING
THROUGH THE SUNRISE HOURS OF FRIDAY.
LOWS TONIGHT WILL DIP INTO THE LOW-MID 40S IN VALLEYS OF THE
NORTHERN MOUNTAINS TO NEAR 60 IN THE SE. IF CLOUDS HOLD OFF OR
BREAK UP...WOULD NOT BE SURPRISED TO SEE SOME READINGS IN THE
UPPER 30S AT SOME OF THE NORMAL COLD SPOTS OF THE NORTH.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
IT WILL BE DRY FRIDAY BUT IT COULD BE RATHER CLOUDY FOR A TIME
UNTIL THE SUBSIDENCE INVERSION MIXES OUT AND CLOUDS CAN BREAK UP.
HIGHS IN THE 60S TO LOWER 70S WILL AVERAGE SOME 5-10 DEG BELOW
NORMAL.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
A SHORTWAVE TROUGH DIGGING SEWD THROUGH THE NRN HIGH PLAINS THIS
MORNING WILL MOVE EASTWARD AND REACH THE GRT LAKES REGION FRI
NIGHT WHILE CONTINUING TO AMPLIFY...TAKING ON A NEGATIVE TILT AS
IT ACCELERATES NEWD ACROSS THE ST LAWRENCE RIVER VLY ON SAT. THE
ENERGY WILL BE IN SUFFICIENTLY CLOSE PROXIMITY TO THE BAROCLINIC
ZONE OVER THE SOUTHEAST STATES FOR A WAVE OF LOW PRESSURE TO
DEVELOP NEAR THE TN VLY/CNTRL APPLCHNS AND LIFT NEWD THRU UPPER OH
VLY/MID ATLC/NORTHEAST ON SAT. MODEST HEIGHT FALLS AND FAVORABLE
JET DYNAMICS ALOFT SHOULD PROVIDE SUFFICIENT LG SCALE FORCING FOR
LIFT...WHILE STRENGTHENING SLY LLJ/WAA RECOVERS PW VALUES TO 1-1.5
INCHES. MODELS SHOW LITTLE IN THE WAY OF INSTABILITY BUT SOME LOW
TOPPED CONVECTION MAY STILL DEVELOP AND PRODUCE LOCAL 0.25 TO 0.50
QPF AMTS. THE TRAILING FRONT SHOULD BE FAIRLY PROGRESSIVE AS IT
CROSSES THRU THE LOCAL AREA..WHICH SHOULD ALSO ACT TO LIMIT PCPN
AMTS. WITH GOOD AGREEMENT IN THE GUIDANCE OPTED TO INCREASE AREA
OF LKLY POPS FOR D3.
FROM SUNDAY TO NEXT THURSDAY (9/18) THE UPPER PATTERN OVER NOAM
WILL FEATURE A WESTERN RIDGE WITH A DOWNSTREAM MEAN TROUGH OVER
THE EAST. WHILE MOST OF THE PERIOD SHOULD BE DRY UNDER THE
INFLUENCE OF MODIFIED CANADIAN HIGH PRESSURE...THERE SEEMS TO BE
BROAD SUPPORT FOR ANOTHER S/WV AND FRONTAL SYSTEM TO BRING SHOWERS
TO THE AREA IN THE LATE MONDAY/TUESDAY TIME FRAME. OTHERWISE MOST
OF THE ORGANIZED PCPN WILL BE FOCUSED TO THE SOUTH NEAR STALLED
FRONT OVER THE CAROLINAS. THE MEAN PATTERN SUPPORTS BELOW AVG
FALL-LIKE READINGS WITH A FEW CHILLY MORNINGS AND COOL DAYS. SOME
PATCHY FROST IS POSSIBLE IN THE NRN TIER WHICH IS NOT THAT FAR
FROM THE CLIMO.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
A COLD FRONT IS MOVING THROUGH THE FLYING AREA. CEILINGS HAVE
LIFTED UP TO VFR FOR THE MOST PART IN THE WARM AIR AHEAD OF THE
FRONT...WHILE BEHIND THE FRONT MVFR AND EVEN AREAS OF IFR ARE
FAIRLY WIDESPREAD IN A PATTERN THAT MORE RESEMBLES THE COLD SEASON
THAN THE LATE SUMMER. THESE LOWER CEILINGS WILL TEND TO LIFT
THROUGH EARLY EVENING WITH MOST SITES BEING VFR BY NIGHTFALL. JST-
BFD ARE USUALLY THE TERMINALS THAT HANG ON TO LOWER CONDITIONS THE
LONGEST AND THIS SHOULD NOT BE AN EXCEPTION.
THERE IS STILL THE POTENTIAL FOR AN ISOLATED HEAVIER SHOWER OR
THUNDERSTORM...WITH LOCALIZED BRIEF FLIGHT RESTRICTIONS...OVER
SERN AREAS AS THE FRONT SWEEPS EAST. THE THREAT WILL DIMINISH
LATER THIS AFTERNOON INTO EARLY EVENING AS THE FRONT MOVES EAST OF
THE AREA.
FORECAST SOUNDINGS SHOW A STRONG LOW LEVEL INVERSION FORMING LATER
TONIGHT AS A SPRAWLING HIGH PRESSURE AREA SPILLS INTO THE REGION.
THIS SHOULD LEAD TO THE REDEVELOPMENT OF SOME LOW CLOUDS AND
POSSIBLY AREAS OF FOG LATER TONIGHT THROUGH THE POST DAWN HOURS
OF FRIDAY MORNING.
OUTLOOK...
FRI...LOW CIGS PSBL EARLY...BCMG VFR.
SAT...VFR/MVFR CIGS WITH SCT SHOWERS.
SUN...PATCHY AM FOG...OTHERWISE VFR.
MON...NO SIG WX.
MON NIGHT - TUE...A COLD FRONT WILL BRING REDUCED CONDITIONS WITH
SHOWERS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...STEINBUGL
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
205 PM EDT THU SEP 11 2014
.SYNOPSIS...
A STRONG COLD WILL MOVE ACROSS THE REGION TODAY. COOL AND DRIER
WEATHER WILL FOLLOW FOR FRIDAY. A NEW DISTURBANCE WILL MOVE
THROUGH THE AREA ON SATURDAY BEFORE HIGH PRESSURE RETURNS FAIR
WEATHER FOR SUNDAY. THE OVERALL PATTERN FAVORS BELOW NORMAL
TEMPERATURES FROM SATURDAY INTO NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
2PM UPDATE...
AS OF 2PM...THE COLD FRONT IS BETWEEN STATE COLLEGE AND ALTOONA
WITH EVEN FEWER SHOWERS ASSOCIATED THAN EARLIER THIS MORNING. THE
UPPER SHORTWAVE IS VERY FLAT AND SHEARED OUT...SO SUPPORT FOR THE
FRONT IS NOT IMPRESSIVE EVEN THOUGH THE AIRMASS DISCONTINUITY IS.
TEMPERATURES HAVE BEEN STEADY OR FALLING OVER NWRN PA ALL DAY
WHILE TEMPS HAVE RISEN INTO THE LOWER 80S OVER THE SERN PART OF
THE AREA.
THE RAP SHOWS VIRTUALLY NO CAPE OR LOW LEVEL CONVERGENCE ALONG
WITH WEAK MID LEVEL LAPSE RATES...AND THE LACK OF SHOWER ACTIVITY
PRETTY MUCH CONFIRMS THIS ANALYZED LACK OF INSTABILITY.
I LOWERED THE OVERALL PROBABILITY OF SHOWERS AND ISOLATED
THUNDERSTORMS OVER MY SERN ZONES AS THE FRONT SWEEPS EAST. THE
NEXT 3-6 HOURS WILL BE THE WINDOW OF BEST OPPORTUNITY FOR RAIN
BEFORE THINGS DRY OUT FOR TONIGHT AND FRIDAY.
THE FRONT WILL PUSH SE OF THE AREA THIS EVENING WITH AN
INITIALLY GUSTY NW FLOW GIVING WAY TO A LIGHTER BREEZE. MODEL
SOUNDINGS SHOW A FAIR AMOUNT OF LOW LEVEL MOISTURE BEING TRAPPED
UNDER A STRENGTHENING SUBSIDENCE INVERSION. LOOKS LIKE LOW CLOUDS
AND EVEN SOME PATCHY FOG WILL REDEVELOP LATER TONIGHT...LASTING
THROUGH THE SUNRISE HOURS OF FRIDAY.
LOWS TONIGHT WILL DIP INTO THE LOW-MID 40S IN VALLEYS OF THE
NORTHERN MOUNTAINS TO NEAR 60 IN THE SE. IF CLOUDS HOLD OFF OR
BREAK UP...WOULD NOT BE SURPRISED TO SEE SOME READINGS IN THE
UPPER 30S AT SOME OF THE NORMAL COLD SPOTS OF THE NORTH.
&&
.SHORT TERM /FRIDAY/...
IT WILL BE DRY FRIDAY BUT IT COULD BE RATHER CLOUDY FOR A TIME
UNTIL THE SUBSIDENCE INVERSION MIXES OUT AND CLOUDS CAN BREAK UP.
HIGHS IN THE 60S TO LOWER 70S WILL AVERAGE SOME 5-10 DEG BELOW
NORMAL.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
SURFACE HIGH SPLITS FRI NIGHT/SAT WITH A PORTION RUNNING EASTWARD
ACROSS S ONTARIO/NEW ENGLAND WHILE THE MAIN HIGH PRESSURE CENTER
REMAINS CENTERED OVER MISSOURI VALLEY. AT THE SAME TIME...A POTENT
UPPER SHORTWAVE SLIDES EAST ALONG THE U.S./CANADA BORDER TURNING
LOW LEVEL FLOW OVER PA BACK TO THE SOUTH BRIEFLY FRI NIGHT INTO
SAT. INCREASED LOW-MID LEVEL FLOW DURING THIS TIME SHOULD TRIGGER
SCT SHOWERS...THOUGH ACCUMS SHOULD BE LIGHT WITH LIMITED MOISTURE
TO WORK WITH.
LEFT SUNDAY INTO WED DRY.
SOME HINTS OF A WEAK TROUGH OVER THE LAKES EARLY NEXT WEEK...BUT
LEFT FCST DRY FOR NOW.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
A COLD FRONT IS MOVING THROUGH THE FLYING AREA. CEILINGS HAVE
LIFTED UP TO VFR FOR THE MOST PART IN THE WARM AIR AHEAD OF THE
FRONT...WHILE BEHIND THE FRONT MVFR AND EVEN AREAS OF IFR ARE
FAIRLY WIDESPREAD IN A PATTERN THAT MORE RESEMBLES THE COLD SEASON
THAN THE LATE SUMMER. THESE LOWER CEILINGS WILL TEND TO LIFT
THROUGH EARLY EVENING WITH MOST SITES BEING VFR BY NIGHTFALL. JST-
BFD ARE USUALLY THE TERMINALS THAT HANG ON TO LOWER CONDITIONS THE
LONGEST AND THIS SHOULD NOT BE AN EXCEPTION.
THERE IS STILL THE POTENTIAL FOR AN ISOLATED HEAVIER SHOWER OR
THUNDERSTORM...WITH LOCALIZED BRIEF FLIGHT RESTRICTIONS...OVER
SERN AREAS AS THE FRONT SWEEPS EAST. THE THREAT WILL DIMINISH
LATER THIS AFTERNOON INTO EARLY EVENING AS THE FRONT MOVES EAST OF
THE AREA.
FORECAST SOUNDINGS SHOW A STRONG LOW LEVEL INVERSION FORMING LATER
TONIGHT AS A SPRAWLING HIGH PRESSURE AREA SPILLS INTO THE REGION.
THIS SHOULD LEAD TO THE REDEVELOPMENT OF SOME LOW CLOUDS AND
POSSIBLY AREAS OF FOG LATER TONIGHT THROUGH THE POST DAWN HOURS
OF FRIDAY MORNING.
OUTLOOK...
FRI...LOW CIGS PSBL EARLY...BCMG VFR.
SAT...VFR/MVFR CIGS WITH SCT SHOWERS.
SUN...PATCHY AM FOG...OTHERWISE VFR.
MON...NO SIG WX.
MON NIGHT - TUE...A COLD FRONT WILL BRING REDUCED CONDITIONS WITH
SHOWERS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...MARTIN
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
321 PM CDT THU SEP 11 2014
.DISCUSSION...
PLENTY OF CHALLENGES THIS FORECAST PACKAGE AS WE TRACK A SLOW-
MOVING FRONT NOW EXTENDING FROM A GATESVILLE...TO CORSICANA...TO
CANTON LINE. A BROKEN LINE OF SHOWERS AND THUNDERSTORMS CONTAINING
LOCALLY HEAVY RAINFALL HAS ERUPTED IN THE PAST 1-2 HOURS ALONG THE
BOUNDARY. IN ADDITION...LOCALIZED FLOODING ISSUES WILL NEED TO BE
MONITORED ALONG THE COLD FRONT WITH THIS BROKEN LINE OF STORMS
WITH RICH PRECIPITABLE WATER VALUES WELL ABOVE 2 INCHES AND HIGH
THETA-E AIR BETWEEN 700-850MB. ANY TRAINING ACTIVITY WILL LIKELY
CAUSE SOME LOCALIZED HYDROLOGIC PROBLEMS. WE WILL CARRY THE HIGHEST
RAIN CHANCES THIS EVENING ALONG AND AHEAD OF THE FRONT OR ACROSS
THE SOUTHEAST HALF OF THE REGION. THE BEST INSTABILITY AND FORCING
WITH THE COLD FRONT WILL MOST LIKELY DRIVE THIS ACTIVITY THROUGH
NIGHTFALL. IN ADDITION...WE HAVE ADDED HIGHER CHANCES ACROSS THE
FAR WESTERN COUNTIES FOR LATE EVENING. THE APPROACH OF A SUBTLE
DISTURBANCE OVER WEST TEXAS WILL LIKELY PROVIDE ENOUGH LIFT TO
SUSTAIN A FEW SHOWER OR STORMS ACROSS THE FAR WESTERN COUNTIES
AFTER SUNSET.
THE WEST TEXAS DISTURBANCE WILL CONTINUE TO MOVE OVER THE RED RIVER
AREA AND SOUTHERN OKLAHOMA TONIGHT. NORTHERN AREAS...ESPECIALLY
THOSE ALONG AND NORTH OF I-20 WILL BE UNDERNEATH THE RIGHT ENTRANCE
REGION OF A 60-70KT JET STREAK STREAMING OVER OKLAHOMA. AS WE HEAD
INTO FRIDAY MORNING...A STRONGER DISTURBANCE CURRENTLY OVER WYOMING
WILL ROTATE SOUTHEAST OVER THE KANSAS/NEBRASKA BORDER AND SHOULD
SHUNT THE JET STREAK A LITTLE FURTHER SOUTH. THE COMBINATION OF
THESE FEATURES WILL PROVIDE THE SYNOPTIC LIFT...WHILE NOCTURNAL
LOW LEVEL WARM ADVECTION OVERRIDES THE SHALLOW FRONTAL INVERSION.
WITH THE FOCUS SHIFTING BACK NORTH...WILL MAINTAIN LIKELY CHANCES
FOR RAINFALL WHICH AT TIMES COULD BE LOCALLY HEAVY...BUT NOT ENOUGH
ALONG WITH ANTECEDENT DRY SOIL CONDITIONS TO ISSUE ANY FLOOD WATCHES
AT THIS POINT. 500-700MB LAPSE RATES WILL BE HOVERING AROUND 6 DEG/KM
WITH BOTH RUC AND NAM12 BUFKIT SOUNDINGS INDICATING A DEEP...BUT
SKINNY LAYER OF CAPE. ALL TOLD...SHOWERS WILL BE LIKELY OVERNIGHT
TONIGHT INTO FRIDAY MORNING ACROSS THESE AREAS WITH EMBEDDED/ELEVATED
THUNDERSTORMS AT TIMES. RAIN CHANCES AFTER NIGHTFALL ACROSS CENTRAL
TEXAS SHOULD DIMINISH TO LOWER CHANCES THAN WHAT WILL BE SEEN
ACROSS THE NORTH. THERE WILL BE QUITE A VARIANCE ON HIGH TEMPERATURES
FROM NORTHWEST TO SOUTHEAST FRIDAY. HIGHS WILL ONLY PUSH TO AROUND
70 DEGREES ACROSS THE FAR NORTHWEST... TO THE LOWER 90S ACROSS THE
FAR SOUTHEAST.
BETTER RAIN CHANCES SHIFT BACK OVER CENTRAL TEXAS ONCE AGAIN
FRIDAY AFTERNOON INTO SATURDAY MORNING. THE PASSAGE OF THE STRONG
SHORTWAVE TO THE NORTH TOWARD NORTHERN MISSOURI AND IOWA WILL HELP
SEND A STRONGER AND DEEPER PUSH OF COOLER AIR INTO THE NORTHERN
COUNTIES WITH THE SOUTH REMAINING WARMER AND MORE UNSTABLE. THE
UPPER HIGH WILL STRENGTHEN SOME BACK OVER THE AREA THIS WEEKEND
WITH JUST LINGERING LOW RAIN CHANCES ACROSS CENTRAL TEXAS WHERE
DEEPER MOISTURE WILL LINGER. THESE CHANCES SHOULD END BY NIGHTFALL
SATURDAY EVENING AS THE ATMOSPHERE STABILIZES. EVEN SO...CLOUD
COVER ON AND ABOVE THE DEEPENING FRONTAL INVERSION WILL MAINTAIN
CONSIDERABLE CLOUDINESS ACROSS THE REGION. THE CLOUDS COMBINED
WITH THE COOLER AIRMASS WILL HOLD HIGHS BETWEEN 75 AND 85 DEGREES
SATURDAY THAT WILL SLOWLY MODIFY TO THE 80S ON SUNDAY.
THE FORECAST AFTER THE WEEKEND BECOMES CHALLENGING ONCE AGAIN AS
WE MONITOR AN UPPER DISTURBANCE ROTATING AROUND THE WESTERN PERIPHERY
OF THE UPPER HIGH OVER THE WESTERN GULF COAST ON MONDAY. BY MONDAY
NIGHT AND TUESDAY...ANOTHER STRONG DISTURBANCE WILL MOVE DOWN
WITHIN NORTHWEST FLOW ALOFT ACROSS THE CENTRAL PLAINS AND DRAG A
SECOND COLD FRONT INTO SOUTHERN PLAINS BY TUESDAY. MOISTURE WILL
BE PLENTIFUL ENOUGH THAT WE HAVE MAINTAINED THE LOW CHANCES FOR
SHOWERS AND STORMS UNTIL TIMING AND ENVIRONMENTAL DETAILS BECOME
CLEARER FOR THAT TIME FRAME AND WE CAN DIAGNOSE WHEN THE BEST
CHANCES WILL OCCUR. THE LATTER HALF OF NEXT WEEK WAS KEPT DRY AND
WARM FOR NOW...AS THE SECOND FRONT WASHES OUT OVER THE SOUTHERN
PART OF THE STATE. HOWEVER...LOW RAIN CHANCES MAY NEED TO BE
EXTENDED ACROSS OUR CENTRAL TEXAS COUNTIES IF THE FRONT STALLS
FURTHER NORTH. HIGH TEMPERATURES WILL MODIFY BACK TO THE MID AND
UPPER 80S WITH A FEW READINGS IN THE LOWER 90S POSSIBLE ACROSS OUR
CENTRAL TEXAS COUNTIES.
05/
&&
.AVIATION...
/ISSUED 214 PM CDT THU SEP 11 2014/
FOR THE 18Z TAFS...PRECIPITATION CHANCES AND TIMING FLIGHT
CATEGORY RESTRICTIONS THIS AFTERNOON AND TONIGHT ARE THE PRIMARY
FORECAST CONCERNS.
FOR THIS AFTERNOON...A COLD FRONT WAS LOCATED JUST TO THE
SOUTHEAST OF WACO...MOVING SLOWLY TO THE SOUTHEAST. NUMEROUS
SHOWERS AND THUNDERSTORMS WERE DEVELOPING ALONG THIS FRONT AS OF
18Z...AND WILL LIKELY CONTINUE TO DO SO THROUGH THE REMAINDER OF
THE AFTERNOON. WENT AHEAD WITH VCTS FROM 18 TO 00Z AT THE WACO TAF
AS A RESULT. FOR THE DFW AREA...THERE WERE SOME SCATTERED SHOWERS
AND THUNDERSTORMS DEVELOPING ACROSS SOUTHEASTERN COLLIN
COUNTY...BUT THESE WERE ELEVATED IN NATURE WELL BEHIND THE FRONT.
SOME OF THIS ELEVATED ACTIVITY MAY BUILD WEST TOWARDS DFW/GKY/DAL
THROUGH THE PEAK HEATING HRS OF THE DAY...SO WENT AHEAD WITH A
MENTION OF VCSH IN THE TAFS THRU 21Z AS A RESULT. WILL AMEND THE
TAFS IF IT LOOKS LIKE THUNDERSTORM ACTIVITY IS GOING TO GET
CLOSER TO THE DFW TAFS THIS AFTERNOON. HIGH MVFR CIGS WILL HANG
AROUND THE DFW AREA THROUGH 21Z...BECOMING LOW VFR THEREAFTER.
THIS EVENING...RAIN SHOWER AND THUNDERSTORM ACTIVITY IS EXPECTED
TO DISSIPATE WITH THE LOSS OF DAYTIME HEATING ACROSS THE REGION.
CIGS SHOULD REMAIN VFR THROUGH MIDNIGHT. MODELS INDICATE THAT LOW-
LEVEL WINDS WILL BECOME SOUTHERLY OVER THE SHALLOW COLD FRONT THIS
EVENING...SETTING UP THE ENVIRONMENT FOR BETTER PRECIPITATION
CHANCES ACROSS THE DFW AREA AFTER MIDNIGHT.
LATE TONIGHT THRU TOMORROW MORNING...ELEVATED SHOWERS AND
THUNDERSTORMS ARE EXPECTED TO DEVELOP NORTH OF THE FRONT AFTER
MIDNIGHT. RAIN CHANCES LOOK BEST AT THE DFW AREA BETWEEN 10 AND
14Z WHEN MOST MODEL GUIDANCE MAXIMIZES LOW-LEVEL LIFT OVER THE
METROPLEX. HAVE VCSH FOR A FEW HOURS ON EITHER SIDE OF THIS
WINDOW...WITH VCTS AND PERSISTENT SHOWERS IN THE 10-14Z TIME FRAME
TO ACCOUNT FOR THIS LIFT. SHOWERS AND THUNDERSTORMS SHOULD
DISSIPATE ACROSS THE DFW AREA DURING THE LATE MORNING HOURS AS
SUBSIDENCE WORKS OVER THE AREA BEHIND THE FRONT.
THE ONLY HAZARDS EXPECTED FROM THUNDERSTORM ACTIVITY ARE CLOUD TO
GROUND LIGHTNING...AND REDUCED VISIBILITY FROM HEAVY RAINFALL.
CAVANAUGH
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 73 75 62 77 66 / 70 70 20 10 10
WACO, TX 73 84 65 79 65 / 40 50 40 30 10
PARIS, TX 71 73 60 75 62 / 70 70 20 10 10
DENTON, TX 70 72 61 77 64 / 70 70 20 10 10
MCKINNEY, TX 70 72 59 75 63 / 70 70 20 10 10
DALLAS, TX 73 76 62 76 67 / 60 70 20 10 10
TERRELL, TX 73 79 63 76 64 / 60 70 30 10 10
CORSICANA, TX 74 83 65 79 65 / 50 50 40 20 10
TEMPLE, TX 72 86 65 78 65 / 30 60 50 30 20
MINERAL WELLS, TX 69 72 59 75 63 / 70 70 20 10 10
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/05
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND FRIDAY
ISSUED AT 254 PM CDT THU SEP 11 2014
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A 1037MB
CANADIAN HIGH PRESSURE SYSTEM BUILDING SOUTHEAST ACROSS THE NORTHERN
PLAINS AND MISSISSIPPI VALLEY. THE COMBO OF NORTHERLY FLOW OFF LAKE
SUPERIOR AND DIURNAL HEATING HAS MAINTAINED THE BROKEN TO OVERCAST
CONDITIONS ACROSS THE REGION. CLOUDS ARE LOOKING MORE CELLULAR OVER
N-C WISCONSIN INDICATING A DIURNAL COMPONENT TO THE CLOUD MASS.
SCATTERED SHOWERS ARE OCCURRING OVER NORTHEAST MINNESOTA AND
NORTHWEST WISCONSIN...WITH HELP FROM A WEAK SHORTWAVE OVER THAT
REGION. THIS WAVE IS LIFTING OFF TO THE NORTHEAST...SO DO NOT THINK
THE SHOWER ACTIVITY WILL REACH INTO N-C WISCONSIN THIS AFTERNOON.
THE NEXT SHORTWAVE IS DIVING SOUTHEAST OVER SOUTHERN MONTANA AND
WILL MOVE EAST TOWARDS THE REGION TOMORROW. THE MAIN CONCERNS ARE
FROST POTENTIAL TONIGHT AND LIGHT RAIN CHANCES TOMORROW.
TONIGHT...CANADIAN HIGH PRESSURE WILL BUILD TOWARDS THE REGION AS A
POTENT SHORTWAVE MOVES ACROSS THE NORTHERN PLAINS. AS SURFACE
PRESSURE RISES...LOW LEVEL FLOW WILL BECOME BROADLY
ANTICYCLONIC...WHICH WILL PROMOTE BREAKING UP OF THE LOW STRATUS.
HOWEVER...EVEN THOUGH THE FLOW WILL BECOME LIGHT...TRAJECTORIES ARE
ONSHORE OFF LAKE SUPERIOR WHERE DELTA T/S ARE SUFFICIENT FOR LAKE
CLOUDS. ADDITIONALLY...THERE IS REALLY NO SOURCE OF DRY AIR TO
BE FOUND ACROSS THE REGION. EVEN THOUGH CLOUDS OVER THE WESTERN
PART OF THE STATE APPEAR TO HAVE A DIURNAL LOOK TO THEM...CLOUDS
ORIGINATING OFF LAKE SUPERIOR COULD BECOME TRAPPED BENEATH THE
NOCTURNAL INVERSION. FURTHERMORE...MID AND HIGH CLOUDS WILL BE
INCREASING AFTER MIDNIGHT AHEAD OF THE SHORTWAVE OVER THE PLAINS.
ALL OF THIS MAKES FOR A LOW CONFIDENCE CLOUD/TEMP/FROST FORECAST.
BECAUSE WE ARE ALREADY OFF TO A COLD START...ANY AMOUNT OF CLEARING
WILL CAUSE TEMPS TO FALL QUICKLY OVER N-C WISCONSIN. MET/MAV/MEX
GUIDANCE ALL SHOW LOW TEMPS IN THE LOWER 30S OVER N-C WISCONSIN. WILL
ERROR ON THE SIDE OF CAUTION BECAUSE OF THIS POTENTIAL AND ISSUE A
FROST ADVISORY FOR N-C WISCONSIN. THE REST OF THE AREA SHOULD SEE
TEMPS IN THE UPPER 30S TO MIDDLE 40S.
FRIDAY...THE POTENT SHORTWAVE WILL MOVE ACROSS THE NORTHERN
MISSISSIPPI VALLEY AND INTO WESTERN WISCONSIN. EVEN THOUGH QG
FORCING AHEAD OF THE WAVE LOOKS RATHER IMPRESSIVE...MOISTURE WILL
ONLY BE 60 TO 80 PCT OF NORMAL AND INSTABILITY IS RATHER POOR.
CHANCES FOR PRECIP WILL IMPROVE DURING THE AFTERNOON AS THE WAVE
APPROACHES AND UPPER DIVERGENCE INCREASES. MODELS ARE ALSO
INDICATING MID-LEVEL CONVERGENCE OVER NORTHEAST AND EAST-CENTRAL
WISCONSIN THAT COULD PROVIDE A FOCUS FOR A BAND OF LIGHT RAIN. WILL
INCREASE PRECIP CHANCE IN THIS AREA FOR THE AFTERNOON.
NORTH-CENTRAL WILL HAVE THE NEXT BEST CHANCE OF SEEING RAIN WHERE
THE DEFORMATION ZONE APPROACHES DURING THE AFTERNOON. SHOULD BE
ANOTHER CLOUDY AND COOL DAY WITH HIGHS IN THE LOW TO MID 50S.
.LONG TERM...FRIDAY NIGHT THROUGH THURSDAY
ISSUED AT 254 PM CDT THU SEP 11 2014
LIGHT RAIN SHOULD END IN EASTERN WISCONSIN FRIDAY EVENING
AS THE UPPER SYSTEM EXITS. IF THERE IS SUFFICIENT CLEARING THERE COULD
BE A FREEZE OR FROST IN NORTHCENTRAL WISCONSIN FRIDAY NIGHT.
SUNNY AND COOL WEATHER SATURDAY AS A SURFACE HIGH MOVES BY. CLOUDS WILL
INCREASE SUNDAY AS A WEAK FRONTAL SYSTEM APPROACHES FROM THE NORTHERN
PLAINS. NOT MUCH MOISTURE AVAILABLE SO ONLY EXPECT SCATTERED SHOWERS
SUNDAY NIGHT AND MONDAY WITH THE FRONTAL PASSAGE. THEN DRY AND SEASONABLE
FOR MUCH OF THE REMINDER OF NEXT WEEK WITH NORTHWEST FLOW ALOFT.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1153 AM CDT THU SEP 11 2014
WIDESPREAD BROKEN MVFR CIGS WILL PREVAIL FOR MUCH OF THE
AFTERNOON...THOUGH EXPECTING CIGS TO SLOWLY RISE...POSSIBLY TO VFR
BY 22-00Z. DIFFICULT TO ESTIMATE WHEN BKN CIGS WILL SCATTER DUE TO
NORTHERLY UNSTABLE FLOW OFF LAKE SUPERIOR CONTINUING THROUGH THE
NIGHT. THE BEST GUESS IS SOMETIME THIS EVENING WHEN THIS FLOW OFF
LAKE SUPERIOR LIGHTENS AND THE INVERSION WEAKENS. BUT IF THE
NOCTURNAL INVERSION DUE TO COOLING TRAPS THE RESIDUAL MOISTURE IN
THE BOUNDARY LAYER...THEN BKN CLOUDS COULD STICK AROUND FOR MUCH OF
THE NIGHT. IF CLOUDS DO SCATTER...THEN BKN CIGS WILL LIKELY DEVELOP
AGAIN BY MIDDAY TOMORROW AHEAD OF THE NEXT UPPER DISTURBANCE.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY FROM MIDNIGHT TONIGHT TO 8 AM CDT FRIDAY FOR
WIZ005-010>012-018-019.
&&
$$
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......MPC