Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 08/28/15
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1127 PM MDT TUE AUG 25 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 301 PM MDT TUE AUG 25 2015
AN UPR RIDGE REMAINS OVR THE AREA TODAY AND SO FAR THIS
AFTERNOON...SHOWERS AND TSTMS HAVE BEEN CONFINED TO PORTIONS OF
THE I-25 CORRIDOR...PALMER DVD AND WESTWARD. THE HRRR SHOWS THE
POTENTIAL FOR SOME ISOLD SHOWERS/TSTMS TO ALSO DEVELOP OR MOVE
OVER THE SERN PLAINS LATER THIS AFTERNOON AND THIS EVENING. MOST
OF THE CONVECTION IS EXPECTED TO END BY MIDNIGHT...HOWEVER THE
HRRR AND NAM SHOW THE POTENTIAL FOR SOME LINGERING ACTIVITY OVR
THE SW MTNS THRU THE NIGHT. THE GFS ALSO SHOW SOME LINGERING
ACTIVITY AFTER MIDNIGHT OVR THE ERN MTNS.
ON WED THE UPR RIDGE REMAINS OVR THE AREA BUT A DISTURBANCE WL MOVE
NORTH-NORTHEASTWARD FROM SWRN CO TO NORTH CENTRAL CO DURING THE DAY.
THIS IS EXPECTED TO BRING AN INCREASE IN SHOWERS/TSTMS ACTIVITY TO
THE CONTDVD. THE MAIN THREAT ALONG THE CONTDVD WL BE HEAVY
RAIN...ESPECIALLY OVR THE BURN SCARS. OVR THE SERN PLAINS...DEW
POINTS ARE EXPECTED TO ONLY BE IN THE UPPER 30S TO LOWER 40S WED
AFTERNOON...AND CONDITIONS SHOULD GENERALLY BE DRY AND HOT AGAIN.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 301 PM MDT TUE AUG 25 2015
...BEST CHANCE OF RAIN FROM WEDNESDAY NIGHT INTO THURSDAY...
...REST OF THE PERIOD MAINLY HOT AND DRY FOR THE LOWLANDS...
ONLY REAL CONCERN IN THE EXTENDED IS WED EVENING...WHEN ONGOING
STORMS OVER THE MTS COULD LEAD TO SOME LOCALIZED FLOODING
CONCERNS...ESPECIALLY FOR THE BURN SCARS AND AREAS OF STEEP TERRAIN.
COULD SEE SOME CONVECTION LINGER THROUGH THE NIGHT INTO THU MORNING.
ONE MINOR TREND IN MODEL GUIDANCE IS THAT THERE SHOULD BE A SECONDARY
UPPER DISTURBANCE THAT COMES THROUGH THURSDAY AFTERNOON OVER THE
PLAINS...AND THIS MIGHT BRING A SLIGHTLY BETTER CHANCE FOR SOME
AFTERNOON AND EVENING STORMS FOR THE PLAINS DURING THAT TIME.
THE UPPER TROUGH DOES NOT REALLY CLEAR THE CWA UNTIL EARLY FRIDAY.
SO WHILE IT STILL LOOKS TO BE FAIRY WARM THU...THERE SHOULD BE A
LITTLE BETTER CHANCE OF STORMS...AND AFTER A COLD FRONT MOVES THROUGH
THU EVENING IT WILL BE A FEW DEGREES COOLER ON FRI...OR RIGHT AROUND
SEASONAL NORMS.
REST OF THE EXTENDED FORECAST LOOKS PRETTY UNEVENTFUL. A PERSISTENT
RIDGE WILL BE OVER THE DESERT SW...AND THIS WILL KEEP MOST OF THE
CWA IN ABOVE AVERAGE TEMPERATURES AND WITH NO WIDESPREAD PRECIP. MOS
GUIDANCE FOR THE EXTENDED AT KPUB FOR EXAMPLE IS WITHIN A COUPLE
DEGREES FOR THE HIGH TEMPS THROUGH EARLY NEXT WEEK. SHOULD SEE LOWER
90S DOMINATE THE TEMPS FOR THE PLAINS DURING THIS TIME. THE MONSOON
WILL BE PRESENT BUT DOES NOT LOOK TERRIBLY ACTIVE. WILL SEE DAILY
CHANCES OF AFTERNOON-EVENING STORMS OVER THE MTN AREAS DURING THIS
PERIOD. STILL A BIT UNCERTAIN HOW A PACNW TROUGH WILL EVOLVE OVER
THE WEEKEND AND INTO NEXT WEEK...BUT MODEL CONSENSUS IS THAT IT WILL
LIFT OFF TO THE E-NE OVER THE NRN ROCKIES AND CANADIAN PLAINS...SO
THE IMPACT FOR OUR AREA LOOKS MINIMAL. ROSE
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1122 PM MDT TUE AUG 25 2015
UPPER WAVE OVER AZ THIS EVENING WILL ROTATE NORTHWARD ACROSS
COLORADO LATE TONIGHT AND THROUGH THE DAY ON WED. EXPECT ISOLATED
TSRA OVER THE SOUTHWEST MOUNTAINS OVERNIGHT...WITH SCT TO NMRS
STORMS OVER MOST MOUNTAINS AND INTERIOR VALLEYS DURING THE DAY
WED. MANY MT PASSES AND HIGHER PEAKS WILL BE OBSCURED FOR MUCH OF
THE DAY WED. AT THE TAF SITES...BEST CHANCE FOR TSRA WILL BE AT
KALS...AND WILL KEEP A VCTS MENTION IN PLACE FOR MUCH OF THE
AFTERNOON/EARLY EVENING. FARTHER EAST AT KPUB AND KCOS...CAN`T
RULE OUT A LATE DAY TSRA AT EITHER SITE...THOUGH CHANCES LOOK TOO
LOW TO INCLUDE IN THE TAF AT THIS POINT. &&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...28
LONG TERM...ROSE
AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS ALBANY NY
428 PM EDT WED AUG 26 2015
.SYNOPSIS...
AN UPPER LEVEL LOW OVER SOUTHEASTERN CANADA AND THE
NORTHEAST WILL BRING ISOLATED TO SCATTERED SHOWERS MAINLY NORTHWEST
OF THE CAPITAL REGION TONIGHT INTO TOMORROW. HIGH PRESSURE WILL
RIDGE IN OVER PENNSYLVANIA AND NEW YORK WITH CLEARING SKIES AND COOL
CONDITIONS THURSDAY NIGHT. THIS SURFACE HIGH WILL YIELD FAIR AND
DRY CONDITIONS FRIDAY INTO FIRST HALF OF THE WEEKEND WITH
TEMPERATURES RETURNING TO ABOVE NORMAL READINGS FOR LATE AUGUST.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
AS OF 418 PM EDT...AN UPPER LEVEL LOW CONTINUES TO BE CENTERED
JUST S/SE OF JAMES BAY OVER SW QUEBEC. WEAK SHORT-WAVE IMPULSES
ROTATING AROUND BASE OF THE TROUGH CONTINUE TO FOCUS SOME LAKE
ENHANCED ISOLD-WDLY SCT RAIN SHOWERS OVER THE WRN DACKS AND CLOSE
TO THE WRN MOHAWK VALLEY. OTHER ISOLD-SCT SHOWERS OR SPRINKLES
CONTINUE OVER WRN NY...NRN PA...AND SE ONTARIO DUE TO THE
VORTICITY ADVECTION WITH THE NEXT SHORT-WAVE EMBEDDED IN THE LONG-
WAVE TROUGH.
THE WATER VAPOR LOOP THIS AFTERNOON SHOWS THE NEXT SPOKE OF ENERGY
MOVING ACROSS LAKE HURON AND GEORGIAN BAY. THE CYCLONIC VORTICITY
ADVECTION AND FETCH OF MOISTURE OFF LAKES ERIE AND ONTARIO SHOULD
KEEP ISOLD-SCT SHOWERS OVER THE WRN-SRN DACKS...THE W-CNTRL
MOHAWK VALLEY AND THE NRN CATSKILLS OVERNIGHT. THE HIGHER CHC POPS
WERE KEPT IN OVER THE WRN DACKS. THE NAM AND HRRR BOTH INDICATED A
FAVORABLE LAKE TRAJECTORY OFF LAKE ONTARIO TONIGHT FOR A BAND OF
LAKE EFFECT/ENHANCED SHOWERS AHEAD OF THE SHORT-WAVE AND UPPER
LEVEL TROUGH AXIS. H850 TEMPS WILL LOWER TO +6C TO +8C AT H850
OVER THE WARM LAKE TEMPS OF +15C +20C ON THE ERN HALF OF LAKE
ONTARIO. SOME LAKE EFFECT CLOUDS WILL STREAM
DOWNSTREAM...ESPECIALLY NORTH AND WEST OF THE CAPITAL DISTRICT.
ANY SHOWERS SHOULD BE LIGHT IN INTENSITY. THE UPPER TROUGH AXIS
BASED ON THE NAM/GFS/ECMWF WILL BE APPROACHING THE HUDSON RIVER
VALLEY BY DAY BREAK.
LOWS TONIGHT WILL RANGE FROM THE U40S TO L50S OVER THE MTNS...AND
GENERALLY LOWER TO MID 50S IN THE VALLEYS.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
TOMORROW...THE UPPER TROUGH AXIS SHOULD CLEAR MOST IF NOT ALL THE
FORECAST AREA BY NOONTIME. A FEW ISOLD-SCT INSTABILITY SHOWERS
WITH THE RESIDUAL COLD POOL IN THE CYCLONIC FLOW MAY PERSIST
NORTHWEST OF THE CAPITAL REGION INTO THE EARLY PM. SUNSHINE WILL
MIX WITH CLOUDS...AND IT WILL BE BREEZY AND COOL WITH H850 TEMPS
OF +7C TO +11C FROM NW TO SE ACROSS THE FCST AREA. HIGH TEMPS WILL
RUN SLIGHTLY BELOW NORMAL WITH LOWER TO M70S IN THE VALLEY
AREAS...EXCEPT OVER THE MID HUDSON VALLEY...AND SRN LITCHFIELD CTY
WHERE SOME U70S ARE POSSIBLE. EXPECT M60S TO L70S OVER THE HILLS
AND MTNS.
THU NIGHT...HIGH PRESSURE BUILDS IN OVER PA AND NY WITH CLEARING
SKIES AND LIGHT TO CALM WINDS. SOME PATCHY VALLEY RADIATIONAL FOG
FORMATION IS POSSIBLE...ESPECIALLY BETWEEN 06Z-12Z. IT SHOULD BE A
GOOD RADIATIONAL COOLING NIGHT WITH THE DIMINISHING WINDS. LOWS
WILL BE IN THE M40S TO AROUND 50F NORTH OF THE CAPITAL
DISTRICT...AND GENERALLY 50-55F TO THE SOUTH...EXCEPT SOME U40S
OVER THE BERKSHIRES...AND ERN CATSKILLS.
FRIDAY INTO SATURDAY...A NICE STRETCH OF LATE AUGUST WX IS
EXPECTED WITH MODERATING TEMPS INTO THE WEEKEND. INITIALLY...THE
MID LEVEL FLOW WILL BE ZONAL ON FRIDAY...WITH THE SFC HIGH OVER
THE NORTHEAST. MOSTLY SUNNY SKIES AND PLEASANT HUMIDITY LEVELS
CONTINUE. TEMPS WILL BE NEAR NORMAL FOR ERN NY AND WRN NEW
ENGLAND. FRI NIGHT...THE SFC HIGH RIDGES IN FROM OFF THE SRN NEW
ENGLAND COAST. LOW AND MID LEVEL HEIGHTS START TO INCREASE.
ANOTHER COOL NIGHT IS EXPECTED WITH LOWS MAINLY IN THE 50S WITH
SOME U40S OVER THE HIGHER TERRAIN. WARM ADVECTION CONTINUES ON
SATURDAY WITH H850 TEMPS OF +14C TO +16C WITH S/SW FLOW IN THE
BOUNDARY LAYER ON THE RIM OF THE OFFSHORE MID AND UPPER RIDGE. MAX
TEMPS SHOULD RISE AT LEAST 5 DEGREES OR SO ABOVE NORMAL. HUMIDITY
LEVELS SLIGHTLY INCREASE WITH DEWPTS IN THE M5OS L60S. A WEAKENING
UPPER LEVEL DISTURBANCE WILL BE APPROACHING FROM THE WEST WITH AN
INCREASE OF SOME CLOUDS LATE IN THE DAY. OVERALL...A NICE START TO
THE LAST WEEKEND IN AUGUST. HIGHS WILL BE IN THE MID TO U70S OVER
THE HIGHER TERRAIN...AND GENERALLY 80-85F IN THE VALLEYS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
TO START THE LONG TERM PERIOD SATURDAY NIGHT INTO SUNDAY
MORNING...HIGH PRESSURE WILL BE ANCHORED OVER THE REGION PROVIDING
FAIR WEATHER CONDITIONS. A ISOLATED CHANCE OF A SHOWER OR
THUNDERSTORM IS POSSIBLE AS WE GO INTO SUNDAY AFTERNOON AS THE
LATEST 26/12Z MODEL AND NUMERICAL DATA SHOW A LOW AMPLITUDE UPPER
LEVEL SHORTWAVE MOVING EAST OUT OF CANADA ACROSS PORTIONS OF OUR FAR
NORTHERN AREAS. COUPLED WITH DIURNAL HEATING TRENDS AND
SOUTHWESTERLY FLOW ADVECTING MOISTURE INTO THE REGION...SOME
PRECIPITATION SUNDAY AFTERNOON IS POSSIBLE.
AS WE GO INTO THE WORK WEEK...OVERALL IT WILL FEATURE DRY CONDITIONS
AS THE UPPER LEVEL RIDGE OF HIGH PRESSURE OUT OVER THE MISSISSIPPI RIVER
VALLEY WILL MOVE EASTWARD OVER THE REGION. AS IT SLOWLY MAKES IT
WAY EAST...MOISTURE FROM THE GULF OF MEXICO RIDING OVER THE
DEVELOPING UPPER LEVEL RIDGE MAY BRING AN ISOLATED SHOWER TO OUR
FAR SOUTHERN AREAS ON WEDNESDAY BUT THAT IS TOO FAR OUT TO SAY
WITH CONFIDENCE AT THIS TIME. HIGH TEMPERATURES THROUGHOUT THE
EXTENDED PERIOD WILL BE WELL ABOVE AVERAGE WITH HIGH TEMPS RANGING
FROM THE UPPER 70S IN THE HIGH TERRAIN TO MID AND EVEN SOME UPPER
80S AS WE GO THROUGH THE MIDDLE OF NEXT WEEK.
&&
.AVIATION /21Z WEDNESDAY THROUGH MONDAY/...
VFR CONDITIONS ARE CURRENTLY IN PLACE AT ALL TAF SITES WITH JUST
SCT-BKN STRATOCU AROUND 4-6 KFT. THE COMBINATION OF DAYTIME
HEATING AND AN UPPER LEVEL DISTURBANCE PASSING BY TO THE NORTH
WILL KEEP THESE CLOUDS AROUND THROUGH THE EARLY EVENING
HOURS...BUT FLYING CONDITIONS WILL CONTINUE TO BE VFR WITH W-NW
SFC WINDS AT 5-10 KTS. ANY RAIN SHOWERS WILL REMAIN NORTH AND WEST
OF THE TAF SITES OVER THE ADIRONDACKS.
WINDS WILL START TO DECREASE THIS EVENING...BUT WILL PROBABLY
CONTINUE AT LIGHT SPEEDS THROUGH THE OVERNIGHT HOURS. WHILE THERE
MAY BE A DECREASE IN CLOUDS FOR THE FIRST PART OF TONIGHT...THE
UPPER LEVEL TROUGH AXIS WILL BE PASSING THROUGH THE REGION FOR
THE LATE NIGHT HOURS. BECAUSE OF THIS...WILL CONTINUE GO WITH AT
LEAST SCT CLOUDS THROUGH THE OVERNIGHT HOURS. THE COMBINATION OF
THESE PASSING CLOUDS...A LINGERING LIGHT BREEZE...AND A DRY
BOUNDARY LAYER SHOULD PREVENT MUCH RADIATIONAL FOG FROM DEVELOPING
TONIGHT. IF WINDS WERE TO DECOUPLE AND CLOUDS WERE LESS THAN
EXPECTED...SOME PATCHES OF FOG COULD BE POSSIBLE...BUT CONFIDENCE
IN THIS OCCURRING IS NOT HIGH ENOUGH TO INCLUDE IN THE TAF AT
THIS TIME.
DURING THE DAY ON THURSDAY...SCT-BKN CLOUDS WILL BE IN PLACE AT
4-5 KFT WILL CONTINUED VFR CONDITIONS. W-SW WINDS WILL BE AROUND
5-10 KTS.
OUTLOOK...
THURSDAY NIGHT: NO OPERATIONAL IMPACT. PATCHY FG.
FRIDAY TO SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
SUNDAY NIGHT TO MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
A BROAD UPPER LEVEL LOW OVER SOUTHEASTERN CANADA AND THE
NORTHEAST WILL BRING ISOLATED TO SCATTERED SHOWERS MAINLY
NORTHWEST OF THE CAPITAL REGION TONIGHT INTO TOMORROW. HIGH
PRESSURE WILL BUILD IN OVER NEW YORK AND NEW ENGLAND WITH CLEARING
SKIES AND COOL CONDITIONS THURSDAY NIGHT. THIS SURFACE HIGH WILL
YIELD FAIR AND DRY CONDITIONS FRIDAY INTO FIRST HALF OF THE
WEEKEND WITH TEMPERATURES RETURNING TO ABOVE NORMAL READINGS FOR
LATE AUGUST.
THE RH VALUES WILL RISE CLOSE TO 100 PERCENT TOMORROW MORNING WITH
SOME DEW FORMATION. THEY WILL LOWER TO 45 TO 60 PERCENT THURSDAY
AFTERNOON...AND THEN INCREASE TO 90 TO 100 PERCENT FRIDAY
MORNING.
THE WINDS WILL BE FROM THE WEST TO NORTHWEST AT LESS THAN 10 MPH
TONIGHT...AND THEN WILL INCREASE FROM THE NORTHWEST AT 10 TO 15
MPH THURSDAY AFTERNOON...AND THEN WILL BECOME LIGHT TO CALM BY
FRIDAY MORNING.
&&
.HYDROLOGY...
NO HYDROLOGIC ISSUES ARE ANTICIPATED OVER THE NEXT 5 DAYS ENDING
MONDAY.
AN UPPER LEVEL TROUGH WILL MOVE ACROSS THE REGION TONIGHT INTO
TOMORROW BRINGING LIGHT ISOLATED TO SCATTERED SHOWERS PRIMARILY
ACROSS THE SOUTHERN ADIRONDACKS. BASIN-AVERAGE RAINFALL VALUES ARE
EXPECTED TO BE UNDER A QUARTER OF AN INCH.
HIGH PRESSURE WILL BUILD IN ACROSS THE REGION THURSDAY NIGHT AND
INTO THE WEEKEND RESULTING IN PRIMARILY DRY WEATHER FOR MOST OF
THE HYDRO SERVICE AREA. A WEAK DISTURBANCE MAY BRING AN ISOLATED
SHOWER OR THUNDERSTORM LATE SUNDAY ESPECIALLY WEST OF THE HUDSON
RIVER VALLEY.
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...WASULA
NEAR TERM...WASULA
SHORT TERM...WASULA
LONG TERM...LFM
AVIATION...FRUGIS
FIRE WEATHER...WASULA
HYDROLOGY...SNYDER/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
418 PM EDT WED AUG 26 2015
.SYNOPSIS...
AN UPPER LEVEL LOW OVER SOUTHEASTERN CANADA AND THE
NORTHEAST WILL BRING ISOLATED TO SCATTERED SHOWERS MAINLY NORTHWEST
OF THE CAPITAL REGION TONIGHT INTO TOMORROW. HIGH PRESSURE WILL
RIDGE IN OVER PENNSYLVANIA AND NEW YORK WITH CLEARING SKIES AND COOL
CONDITIONS THURSDAY NIGHT. THIS SURFACE HIGH WILL YIELD FAIR AND
DRY CONDITIONS FRIDAY INTO FIRST HALF OF THE WEEKEND WITH
TEMPERATURES RETURNING TO ABOVE NORMAL READINGS FOR LATE AUGUST.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
AS OF 418 PM EDT...AN UPPER LEVEL LOW CONTINUES TO BE CENTERED
JUST S/SE OF JAMES BAY OVER SW QUEBEC. WEAK SHORT-WAVE IMPULSES
ROTATING AROUND BASE OF THE TROUGH CONTINUE TO FOCUS SOME LAKE
ENHANCED ISOLD-WDLY SCT RAIN SHOWERS OVER THE WRN DACKS AND CLOSE
TO THE WRN MOHAWK VALLEY. OTHER ISOLD-SCT SHOWERS OR SPRINKLES
CONTINUE OVER WRN NY...NRN PA...AND SE ONTARIO DUE TO THE
VORTICITY ADVECTION WITH THE NEXT SHORT-WAVE EMBEDDED IN THE LONG-
WAVE TROUGH.
THE WATER VAPOR LOOP THIS AFTERNOON SHOWS THE NEXT SPOKE OF ENERGY
MOVING ACROSS LAKE HURON AND GEORGIAN BAY. THE CYCLONIC VORTICITY
ADVECTION AND FETCH OF MOISTURE OFF LAKES ERIE AND ONTARIO SHOULD
KEEP ISOLD-SCT SHOWERS OVER THE WRN-SRN DACKS...THE W-CNTRL
MOHAWK VALLEY AND THE NRN CATSKILLS OVERNIGHT. THE HIGHER CHC POPS
WERE KEPT IN OVER THE WRN DACKS. THE NAM AND HRRR BOTH INDICATED A
FAVORABLE LAKE TRAJECTORY OFF LAKE ONTARIO TONIGHT FOR A BAND OF
LAKE EFFECT/ENHANCED SHOWERS AHEAD OF THE SHORT-WAVE AND UPPER
LEVEL TROUGH AXIS. H850 TEMPS WILL LOWER TO +6C TO +8C AT H850
OVER THE WARM LAKE TEMPS OF +15C +20C ON THE ERN HALF OF LAKE
ONTARIO. SOME LAKE EFFECT CLOUDS WILL STREAM
DOWNSTREAM...ESPECIALLY NORTH AND WEST OF THE CAPITAL DISTRICT.
ANY SHOWERS SHOULD BE LIGHT IN INTENSITY. THE UPPER TROUGH AXIS
BASED ON THE NAM/GFS/ECMWF WILL BE APPROACHING THE HUDSON RIVER
VALLEY BY DAY BREAK.
LOWS TONIGHT WILL RANGE FROM THE U40S TO L50S OVER THE MTNS...AND
GENERALLY LOWER TO MID 50S IN THE VALLEYS.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
TOMORROW...THE UPPER TROUGH AXIS SHOULD CLEAR MOST IF NOT ALL THE
FORECAST AREA BY NOONTIME. A FEW ISOLD-SCT INSTABILITY SHOWERS
WITH THE RESIDUAL COLD POOL IN THE CYCLONIC FLOW MAY PERSIST
NORTHWEST OF THE CAPITAL REGION INTO THE EARLY PM. SUNSHINE WILL
MIX WITH CLOUDS...AND IT WILL BE BREEZY AND COOL WITH H850 TEMPS
OF +7C TO +11C FROM NW TO SE ACROSS THE FCST AREA. HIGH TEMPS WILL
RUN SLIGHTLY BELOW NORMAL WITH LOWER TO M70S IN THE VALLEY
AREAS...EXCEPT OVER THE MID HUDSON VALLEY...AND SRN LITCHFIELD CTY
WHERE SOME U70S ARE POSSIBLE. EXPECT M60S TO L70S OVER THE HILLS
AND MTNS.
THU NIGHT...HIGH PRESSURE BUILDS IN OVER PA AND NY WITH CLEARING
SKIES AND LIGHT TO CALM WINDS. SOME PATCHY VALLEY RADIATIONAL FOG
FORMATION IS POSSIBLE...ESPECIALLY BETWEEN 06Z-12Z. IT SHOULD BE A
GOOD RADIATIONAL COOLING NIGHT WITH THE DIMINISHING WINDS. LOWS
WILL BE IN THE M40S TO AROUND 50F NORTH OF THE CAPITAL
DISTRICT...AND GENERALLY 50-55F TO THE SOUTH...EXCEPT SOME U40S
OVER THE BERKSHIRES...AND ERN CATSKILLS.
FRIDAY INTO SATURDAY...A NICE STRETCH OF LATE AUGUST WX IS
EXPECTED WITH MODERATING TEMPS INTO THE WEEKEND. INITIALLY...THE
MID LEVEL FLOW WILL BE ZONAL ON FRIDAY...WITH THE SFC HIGH OVER
THE NORTHEAST. MOSTLY SUNNY SKIES AND PLEASANT HUMIDITY LEVELS
CONTINUE. TEMPS WILL BE NEAR NORMAL FOR ERN NY AND WRN NEW
ENGLAND. FRI NIGHT...THE SFC HIGH RIDGES IN FROM OFF THE SRN NEW
ENGLAND COAST. LOW AND MID LEVEL HEIGHTS START TO INCREASE.
ANOTHER COOL NIGHT IS EXPECTED WITH LOWS MAINLY IN THE 50S WITH
SOME U40S OVER THE HIGHER TERRAIN. WARM ADVECTION CONTINUES ON
SATURDAY WITH H850 TEMPS OF +14C TO +16C WITH S/SW FLOW IN THE
BOUNDARY LAYER ON THE RIM OF THE OFFSHORE MID AND UPPER RIDGE. MAX
TEMPS SHOULD RISE AT LEAST 5 DEGREES OR SO ABOVE NORMAL. HUMIDITY
LEVELS SLIGHTLY INCREASE WITH DEWPTS IN THE M5OS L60S. A WEAKENING
UPPER LEVEL DISTURBANCE WILL BE APPROACHING FROM THE WEST WITH AN
INCREASE OF SOME CLOUDS LATE IN THE DAY. OVERALL...A NICE START TO
THE LAST WEEKEND IN AUGUST. HIGHS WILL BE IN THE MID TO U70S OVER
THE HIGHER TERRAIN...AND GENERALLY 80-85F IN THE VALLEYS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
TO START THE LONG TERM PERIOD SATURDAY NIGHT INTO SUNDAY
MORNING...HIGH PRESSURE WILL BE ANCHORED OVER THE REGION PROVIDING
FAIR WEATHER CONDITIONS. A ISOLATED CHANCE OF A SHOWER OR
THUNDERSTORM IS POSSIBLE AS WE GO INTO SUNDAY AFTERNOON AS THE
LATEST 26/12Z MODEL AND NUMERICAL DATA SHOW A LOW AMPLITUDE UPPER
LEVEL SHORTWAVE MOVING EAST OUT OF CANADA ACROSS PORTIONS OF OUR FAR
NORTHERN AREAS. COUPLED WITH DIURNAL HEATING TRENDS AND
SOUTHWESTERLY FLOW ADVECTING MOISTURE INTO THE REGION...SOME
PRECIPITATION SUNDAY AFTERNOON IS POSSIBLE.
AS WE GO INTO THE WORK WEEK...OVERALL IT WILL FEATURE DRY CONDITIONS
AS THE UPPER LEVEL RIDGE OF HIGH PRESSURE OUT OVER THE MISSISSIPPI RIVER
VALLEY WILL MOVE EASTWARD OVER THE REGION. AS IT SLOWLY MAKES IT
WAY EAST...MOISTURE FROM THE GULF OF MEXICO RIDING OVER THE
DEVELOPING UPPER LEVEL RIDGE MAY BRING AN ISOLATED SHOWER TO OUR
FAR SOUTHERN AREAS ON WEDNESDAY BUT THAT IS TOO FAR OUT TO SAY
WITH CONFIDENCE AT THIS TIME. HIGH TEMPERATURES THROUGHOUT THE
EXTENDED PERIOD WILL BE WELL ABOVE AVERAGE WITH HIGH TEMPS RANGING
FROM THE UPPER 70S IN THE HIGH TERRAIN TO MID AND EVEN SOME UPPER
80S AS WE GO THROUGH THE MIDDLE OF NEXT WEEK.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
VFR CONDITIONS ARE CURRENTLY IN PLACE AT ALL TAF SITES WITH JUST
SCT-BKN STRATOCU AROUND 4-6 KFT. THE COMBINATION OF DAYTIME
HEATING AND AN UPPER LEVEL DISTURBANCE PASSING BY TO THE NORTH
WILL KEEP THESE CLOUDS AROUND THROUGH THE EARLY EVENING
HOURS...BUT FLYING CONDITIONS WILL CONTINUE TO BE VFR WITH W-NW
SFC WINDS AT 5-10 KTS. ANY RAIN SHOWERS WILL REMAIN NORTH AND WEST
OF THE TAF SITES OVER THE ADIRONDACKS.
WINDS WILL START TO DECREASE THIS EVENING...BUT WILL PROBABLY
CONTINUE AT LIGHT SPEEDS THROUGH THE OVERNIGHT HOURS. WHILE THERE
MAY BE A DECREASE IN CLOUDS FOR THE FIRST PART OF TONIGHT...THE
UPPER LEVEL TROUGH AXIS WILL BE PASSING THROUGH THE REGION FOR
THE LATE NIGHT HOURS. BECAUSE OF THIS...WILL CONTINUE GO WITH AT
LEAST SCT CLOUDS THROUGH THE OVERNIGHT HOURS. THE COMBINATION OF
THESE PASSING CLOUDS...A LINGERING LIGHT BREEZE...AND A DRY
BOUNDARY LAYER SHOULD PREVENT MUCH RADIATIONAL FOG FROM DEVELOPING
TONIGHT. IF WINDS WERE TO DECOUPLE AND CLOUDS WERE LESS THAN
EXPECTED...SOME PATCHES OF FOG COULD BE POSSIBLE...BUT CONFIDENCE
IN THIS OCCURRING IS NOT HIGH ENOUGH TO INCLUDE IN THE TAF AT
THIS TIME.
DURING THE DAY ON THURSDAY...SCT-BKN CLOUDS WILL BE IN PLACE AT
4-5 KFT WILL CONTINUED VFR CONDITIONS. W-SW WINDS WILL BE AROUND
5-10 KTS.
OUTLOOK...
THURS NIGHT-SAT NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
SUN NIGHT-MON: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
A BROAD UPPER LEVEL LOW OVER SOUTHEASTERN CANADA AND THE
NORTHEAST WILL BRING ISOLATED TO SCATTERED SHOWERS MAINLY
NORTHWEST OF THE CAPITAL REGION TONIGHT INTO TOMORROW. HIGH
PRESSURE WILL BUILD IN OVER NEW YORK AND NEW ENGLAND WITH CLEARING
SKIES AND COOL CONDITIONS THURSDAY NIGHT. THIS SURFACE HIGH WILL
YIELD FAIR AND DRY CONDITIONS FRIDAY INTO FIRST HALF OF THE
WEEKEND WITH TEMPERATURES RETURNING TO ABOVE NORMAL READINGS FOR
LATE AUGUST.
THE RH VALUES WILL RISE CLOSE TO 100 PERCENT TOMORROW MORNING WITH
SOME DEW FORMATION. THEY WILL LOWER TO 45 TO 60 PERCENT THURSDAY
AFTERNOON...AND THEN INCREASE TO 90 TO 100 PERCENT FRIDAY
MORNING.
THE WINDS WILL BE FROM THE WEST TO NORTHWEST AT LESS THAN 10 MPH
TONIGHT...AND THEN WILL INCREASE FROM THE NORTHWEST AT 10 TO 15
MPH THURSDAY AFTERNOON...AND THEN WILL BECOME LIGHT TO CALM BY
FRIDAY MORNING.
&&
.HYDROLOGY...
NO HYDROLOGIC ISSUES ARE ANTICIPATED OVER THE NEXT 5 DAYS ENDING
MONDAY.
AN UPPER LEVEL TROUGH WILL MOVE ACROSS THE REGION TONIGHT INTO
TOMORROW BRINGING LIGHT ISOLATED TO SCATTERED SHOWERS PRIMARILY
ACROSS THE SOUTHERN ADIRONDACKS. BASIN-AVERAGE RAINFALL VALUES ARE
EXPECTED TO BE UNDER A QUARTER OF AN INCH.
HIGH PRESSURE WILL BUILD IN ACROSS THE REGION THURSDAY NIGHT AND
INTO THE WEEKEND RESULTING IN PRIMARILY DRY WEATHER FOR MOST OF
THE HYDRO SERVICE AREA. A WEAK DISTURBANCE MAY BRING AN ISOLATED
SHOWER OR THUNDERSTORM LATE SUNDAY ESPECIALLY WEST OF THE HUDSON
RIVER VALLEY.
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...WASULA
NEAR TERM...WASULA
SHORT TERM...WASULA
LONG TERM...LFM
AVIATION...FRUGIS
FIRE WEATHER...WASULA
HYDROLOGY...SNYDER/WASULA
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
348 PM EDT WED AUG 26 2015
.SYNOPSIS...
HIGH PRESSURE ACROSS THE UPPER GREAT LAKES REGION WILL SETTLE ACROSS
THE DELAWARE VALLEY BY FRIDAY AND THEN MOVE OFFSHORE THIS WEEKEND. A
LOW PRESSURE SYSTEM AND FRONT WILL AFFECT THE WEATHER SUNDAY AND
INTO EARLY MONDAY. MORE HIGH PRESSURE BUILDS ACROSS THE AREA NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
A GFS AND WRF-NMMB/NAM BLEND WOULD WORK THE BEST AS
INITIALIZING AT 500MB EASTERN CONUS WHILE THE GFS REMAINS BETTER OUT
WEST. THE SAME COMPROMISE WOULD WORK BEST AS A 925MB INITIALIZATION.
BUT THE GFS ALONE LOOKED BETTER AT 850MB. THE INITIALIZATION DP/DT
CONTINUES TO SHOW MORE RIDGING THAN FORECASTED IN THE WESTERN CONUS,
BUT GENERALLY A FLATTER TROUGH IN THE EASTERN CONUS AND SOUTHEAST
CANADA.
GIVEN THE APPEARANCE OF THE CUMULUS AND CONTINUING CORROBORATION
FROM RECENT HRRR RUNS, WE WILL KEEP THE ISOLATED SPRINKLES OVER
THE FAR NORTHWEST FOR THE NEXT COUPLE OF HOURS.
THE MAINLY CHANNELIZED VORT MAX IS EXPECTED TO REMAIN ACROSS THE
NORTHWEST PART OF OUR CWA INTO THE OVERNIGHT, WITH THE LAST SHORT
WAVE ROUNDING THE BASE OF THE TROF TOWARD MORNING. TENDENCY IS FOR
WINDS TO BE LIGHTER THAN MODEL EXPECTATIONS PRECEDING THESE FEATURES
ON ONE HAND. ON THE OTHER HAND, IT DOES RAISE THE UNCERTAINTY AS TO
LINGERING CLOUDINESS, ESPECIALLY NORTHWEST. VISIBLE SATELLITE IS
SHOWING PLENTY OF CLOUDINESS UPSTREAM AND SOME OF THE MORE HI RES
MODELS DO KEEP LOW LEVEL MOISTURE GOING INTO THE EVENING. BUT, A
TRAPPING INVERSION IS NOT BEING INDICATED. THUS THE FORECAST PLAN
FOR THE NORTHWEST PART OF OUR CWA IS TO AVERAGE PARTLY CLOUDY FOR
TONIGHT WITH A GENERALLY MORE HIGHER CONFIDENT AND CLEARER FORECAST
SOUTHEAST.
BOUNDARY LAYER WINDS ARE PREDICTED TO BE LIGHT ENOUGH FOR
DECOUPLING, ESPECIALLY IN MORE SHELTERED AREAS. GIVEN THE AFTERNOON
DEW POINTS, WE WENT WITH THE STAT GUIDANCE TREND OF LOWERING MINIMUM
TEMPERATURES A BIT IN RURAL/OUTLYING AREAS. HIGHEST CONFIDENCE IS
IN THE SOUTHERN PART OF OUR CWA. CLOUDS MAY MAKE OUR MINS NORTH TOO
LOW.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
WITH THE LAST OF THE SHORT WAVES MOVING OFFSHORE BY EARLY AFTERNOON
THURSDAY, THE TROF FLATTENING AND A HIGH PRESSURE SYSTEM BUILDING
INTO THE EASTERN GREAT LAKES, EVEN MORE OF A CHAMBER OF COMMERCE
LATE AUGUST DAY IS PREDICTED FOR OUR CWA.
THE MODELS DO PASS THE 250MB JET OVER DELMARVA. THEY ARE NOT SHOWING
ANY JET LAYER MOISTURE AT THIS TIME. CUMULUS COVERAGE OVERALL SHOULD
BE LESS THAN TODAY. THE THERMAL TROF PASSES THROUGH AND THE
PREDICTED THERMALS SUGGEST ABOUT A 1F DROP OFF IN MAX TEMPS FROM
TODAY. USING PREDICTED 925MB TEMPS, WE WILL FOLLOW A GFS AND NAM MOS
COMPROMISE. A BRIEF NORTHWEST SURGE BEHIND THE COLD FRONT SHOULD
BECOME LIGHTER AGAIN. ALONG AND NEAR THE COAST AND BAYS, SOME SEA
BREEZE INDUCED WINDS COULD DEVELOP.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
5-WAVE MODEL GUIDANCE SHOWS A BUILDING SOUTHEAST RIDGE THROUGH A
MAJORITY OF THE LONGTERM PERIOD WITH MODERATING TEMPERATURES AND
HUMIDITY.
FRIDAY - SATURDAY...EXPECTING A DRY FORECAST THESE DAYS WITH A WEAK
FRONT NEARING FROM THE NORTHWEST. SOME GUIDANCE IS HINTING AT SHOWER
ACTIVITY ACROSS THE NORTHERN SATURDAY AFTERNOON WITH A BIT OF A
WEAKNESS IN THE PATTERN ALOFT BUT THINKING THAT CONVECTIVE
TEMPERATURES SHOULD BE OUT OF REACH AND THE BETTER FORCING IS STILL
FARTHER TO OUR NORTH AND WEST...WE STAY DRY. BOTH DAYS WE EXPECT
TEMPERATURES IN THE MID-80S WITH DEWPOINTS CLOSE TO 60F.
SUNDAY - MONDAY...THE AFOREMENTIONED COLD FRONT GETS CLOSER BUT WITH
IT DOESN`T REALLY PACK A PUNCH BUT WE CONTINUE THE SLIGHT CHANCE
WITH SOMEWHAT BETTER INSTABILITY. HIGH PRESSURE SLIDES OFF THE COAST
AND ALLOWS FOR BETTER AIRMASS MODIFICATION SO WE WILL SEE AN
INCREASE IN HUMIDITY AND INSTABILITY. HIGHS BOTH DAYS APPROACH, IF
NOT EXCEED, 90F.
TUESDAY - WEDNESDAY...NO APPRECIABLE RAIN EXPECTED EITHER DAY WITH
SOUTHEAST RIDGE AXIS OVERHEAD. CONTINUED HEAT AND HUMIDITY INCREASE
IS EXPECTED BUT IT DOES APPEAR THAT THE CORE OF THE WARMEST 925MB
TEMPERATURES STAYS TO THE SOUTH AND WEST OF THE REGION. NONE-THE-
LESS 90F IS NOT OUT OF THE QUESTION EACH AFTERNOON.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE,
KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS.
18Z TAFS WERE VFR.
REST OF THIS AFTERNOON...A HIGH BASED CUMULUS DECK, BECOMING A CIG
AT TIMES AT THE NORTHWEST TERMINALS AND AIRPORTS. WEST WINDS WILL BE
CLOSE TO 10 KNOTS. THE SEA BREEZE FRONT IS EXPECTED TO REMAIN NEAR
THE IMMEDIATE NJ AND DE COAST AND NOT MAKE IT INLAND OR TO KACY.
TONIGHT...THE CUMULUS CLOUDS SHOULD DISSIPATE, ESPECIALLY I95
CORRIDOR SOUTHEAST. WINDS WILL BE LIGHT FROM THE NORTHWEST AND MORE
SHELTERED AIRPORTS/TERMINALS MAY GO CALM FOR A WHILE. NO VSBY
RESTRICTIONS AT THE TERMINALS. LATE TONIGHT ANOTHER UPPER AIR
DISTURBANCE MIGHT BRING SOME MID LEVEL CLOUDS ACROSS THE AREA AGAIN.
HIGHEST CONFIDENCE NORTHWEST AIRPORTS AND TERMINALS.
THURSDAY...A NEAR CARBON COPY OF TODAY. SOME HIGH BASED CUMULUS
CLOUDS SHOULD DEVELOP AGAIN, PROBABLY LESS OVERALL COVERAGE THAN
TODAY. NORTHWEST WINDS SHOULD AVERAGE 5 TO 10 KNOTS. A SEA BREEZE
FRONT DURING THE AFTERNOON MIGHT MAKE MORE OF AN INLAND INTRUSION.
OUTLOOK...
THURSDAY NIGHT THRU SATURDAY NIGHT...MOSTLY VFR. PATCHY FOG PSBL
DURING THE PREDAWN HOURS.
SUNDAY - MONDAY...MOSTLY VFR. SHOWERS POSSIBLE WITH LOWER
CONDITIONS.
&&
.MARINE...
SUB SMALL CRAFT ADVISORY CONDITIONS WILL CONTINUE TONIGHT AND
THURSDAY.
SEA BREEZE INDUCED CIRCULATIONS LATE THIS AFTERNOON INTO THIS
EVENING SHOULD BECOME A PREVAILING WEST TO NORTHWEST FLOW AGAIN
TONIGHT. MESOSCALE MODELS HAVE THE STRONGEST (POSSIBLY EXCEEDING 15
KNOTS) SOUTHERLY FLOW EARLY OFF THE OCEAN AND ATLANTIC COUNTY COASTS
WITH LESS VARIATION IN SPEEDS WITH THE NORTHWEST FLOW OVERNIGHT.
AS THE OVERALL PRESSURE GRADIENT WEAKENS AGAIN DURING THE DAY ON
THURSDAY, A MORE VARIABLE SEA BREEZE INDUCED WIND FLOW SHOULD
DEVELOP AGAIN ON THE OCEAN WATERS. WE ARE NOT AS CERTAIN ABOUT AN UP
(SOUTHEASTERLY WINDS) THE DELAWARE BAY FLOW OCCURRING. SUSTAINED
WIND SPEEDS THURSDAY SHOULD REMAIN AT 15 KNOTS OR LESS.
OUTLOOK...
SUB-SCA CONDITIONS THRU THE PERIOD. SEAS WILL BUILD TO AROUND 4 FT
ON THE OCEAN SAT NIGHT INTO SUNDAY. WIDELY SCT SHOWERS/TSTMS
POSSIBLE SUN.
&&
.RIP CURRENTS...
WE WILL CONTINUE THE MODERATE RISK FOR THE FORMATION OF DANGEROUS
RIP CURRENT ALONG THE NJ BEACHES FOR THE REST OF THE DAY. A MORE
FAVORABLE WIND FLOW FOR STRONGER RIP CURRENTS IS STARTING TO
DEVELOP.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...O`HARA
NEAR TERM...GIGI
SHORT TERM...GIGI
LONG TERM...HEAVENER
AVIATION...GIGI/HEAVENER/O`HARA
MARINE...GIGI/HEAVENER/O`HARA
RIP CURRENTS...GIGI
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
918 PM EDT THU AUG 27 2015
.UPDATE...
00Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS THE THE UPPER LEVEL
PATTERN OVER THE EASTERN CONUS IS STILL DOMINATED BY A DEEP
LONGWAVE TROUGH EXTENDING FROM THE EASTERN GREAT LAKES TO THE
NORTH-CENTRAL GULF OF MEXICO. THIS TROUGH AXIS IS STILL OFF TO OUR
NORTHWEST AND WEST AND SEPARATES A REGION OF VERY DRY MID/UPPER
LEVEL AIR OVER MUCH OF THE SOUTHEAST CONUS...FROM A MOIST UPPER
LEVEL ENVIRONMENT WITHIN THE SOUTHERN STREAM FLOW ON THE EASTERN
SIDE OF THE TROUGH. THIS MOIST ENVIRONMENT COVERS THE ENTIRE
FLORIDA PENINSULA AND HAS BEEN RESPONSIBLE FOR ANOTHER SHOWERY
PERIOD ACROSS MANY OF OUR ZONES.
AT THE SURFACE...THE GRADIENT IS QUITE WEAK OVER THE PENINSULA AND
EASTERN GULF BETWEEN A WEAK SURFACE TROUGH OVER THE SOUTHERN GULF
OF MEXICO AND CONTINENTAL HIGH PRESSURE TOWARD THE MID-ATLANTIC
STATES. AS THIS HIGH BUILDS SOUTHWARD A BIT ON FRIDAY...OUR FLOW
IN THE LOWER LEVELS WILL BECOME A BIT MORE DEFINED FROM THE
SOUTHEAST. UNFORTUNATELY THIS IS NOT GOOD NEWS FOR THE SATURATED
AREAS OF THE FORECAST AREA...AS SOUTHEAST FLOW IN THE SUMMER IS
GENERALLY OUR FAVORED FLOW FOR THE MOST WIDESPREAD AND STRONG
CONVECTION.
WITH THAT IN MIND...AFTER A FAIRLY DRY PERIOD ACROSS THE LAND MASS
THROUGH A GOOD PORTION OF TONIGHT...WE WILL BEGIN TO SEE
INCREASING CHANCES FOR SHOWERS NEAR THE COAST AND OVER THE NEAR
SHORE WATERS AS WE APPROACH DAWN. THE BEST CHANCE OF SHOWERS
DURING THE MORNING HOURS WILL BE NEAR THE COAST...BUT BY AFTERNOON
WITH THE DIURNAL HEATING...AND FAVORED WEST COAST SEA-BREEZE
CONVERGENCE...DECENT COVERAGE OF SHOWERS AND STORMS WILL ONCE
AGAIN BE IN THE FORECAST FOR MOST AREAS. SOME OF THE RAINFALL IS
LIKELY TO BE ON THE HEAVY SIDE...AND CONDITIONS WILL NEED TO BE
MONITORED CLOSELY...ESPECIALLY DOWN TOWARD CHARLOTTE AND LEE
COUNTIES...WHERE SIGNIFICANT RAINFALL TOTALS HAVE BEEN SEEN OVER
THE PAST 48 HOURS.
&&
.AVIATION...
28/00Z-29/00Z. IN THE WAKE OF EARLIER SHRA/TSRA...PREVAILING VFR
CONDITIONS HAVE DEVELOPED AT ALL TERMINALS. THIS TREND IS EXPECTED
TO CONTINUE...WITH WINDS GRADUALLY SHIFTING TO THE SE/E OVERNIGHT.
SCT SHRA/TSRA LOOK TO DEVELOP AGAIN FROM 14Z TO 18Z FRI...
LINGERING INTO THE EVENING HOURS. MVFR/IFR CIGS AND GUSTY WINDS
CAN BE EXPECTED IN AND AROUND THUNDERSTORMS.
&&
.MARINE...
WEAK GRADIENT ACROSS THE WATERS WILL CREATE WINDS LESS
THAN 15 KNOTS WITH SEAS LESS THAN 3 FEET THROUGH AT LEAST
SATURDAY. THE EVENTUAL TRACK AND INTENSITY OF TROPICAL STORM
ERIKA WILL DETERMINE POTENTIAL INCREASES IN WINDS AND SEAS OVER
THE WATERS BY THE EARLY PORTION OF NEXT WEEK. MAIN HAZARD THROUGH
THE WEEKEND WILL BE SCATTERED MAINLY OVERNIGHT AND MORNING
THUNDERSTORMS WHICH WILL CREATE LOCALLY GUSTY WINDS...AND FREQUENT
CLOUD TO WATER LIGHTNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 75 91 77 88 / 20 60 30 60
FMY 77 92 76 90 / 20 70 30 60
GIF 73 92 75 90 / 20 70 20 60
SRQ 77 90 76 88 / 30 60 30 60
BKV 74 91 74 87 / 20 60 20 60
SPG 78 91 79 88 / 20 60 30 60
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE/MARINE...MROCZKA
AVIATION...AUSTIN
AREA FORECAST DISCUSSION
NWS MIAMI FL
205 PM EDT WED AUG 26 2015
.AVIATION...
ONGOING CONVECTION CONTINUES TO AFFECT MAINLY THE ATLANTIC COAST
THIS AFTERNOON. LATEST HRRR ALSO KEEPS THIS TREND THROUGH THE
EARLY EVENING HOURS WITH SOUTHWEST FLOW ALOFT. THEREFORE KEPT
VCTS AT ALL EAST COAST SITES THROUGH 00Z. DEEP MOISTURE IS
EXPECTED TO LINGER ACROSS ALL OF SOUTH FLORIDA THROUGH THE TAF
PERIOD WITH VCSH/VCTS PREVAILING.
&&
.PREV DISCUSSION... /ISSUED 945 AM EDT WED AUG 26 2015/
UPDATE...QUITE MOIST AND UNSTABLE ATMOSPHERE IN PLACE ACROSS S
FLORIDA ALREADY THIS MORNING WITH THE 12Z SOUNDING SHOWING PWATS
AROUND 2.3" ALONG WITH 700-500 MB LAPSE RATES DOWN TO 6C/KM AND
500MB A SLIGHTLY BELOW NORMAL -7C. CONVECTION HAS ALREADY BEEN
QUITE PLENTIFUL OVER BOTH THE GULF AND ATLANTIC WATERS THIS
MORNING WITH WEAK CONVERGENCE BAND TRACING OUT LOW LEVEL RIDGE
AXIS ACROSS FL STRAITS AND FAR S FLORIDA.
EXPECT AN ACTIVE DAY ACROSS THE REGION WITH SHOWERS AND STORMS
INITIATING BY LATE MORNING/EARLY AFTERNOON. S-SW FLOW WILL HOLD
BACK EAST COAST SEA BREEZE DEVELOPMENT AN HOUR OR TWO...BUT NOT
STOP IT ALTOGETHER...AND ENHANCE GULF BREEZE. BEST RAIN CHANCES
WILL BE OVER THE EASTERN INTERIOR WITH ACTIVITY MOVING OFF TO THE
NORTH- NORTHEAST. PROFILE SUGGESTS THE POSSIBILITY FOR A FEW
STRONGER STORMS WITH GUSTY WINDS AROUND 40MPH...FREQUENTLY HEAVY
RAIN...AND LOCALLY HEAVY RAINFALL AS OVERALL STORM MOTION REMAINS
SLOW.
PREV DISCUSSION... /ISSUED 350 AM EDT WED AUG 26 2015/
DISCUSSION...THE MAJOR SYNOPTIC FEATURES ACROSS THE REGION
INCLUDE A STATIONARY FRONT ACROSS THE NORTHERN GULF...A LARGE
AMPLITUDE UPPER LEVEL TROUGH ACROSS THE EASTERN CONUS AND INTO THE
CENTRAL GULF WITH DEEP TROPICAL MOISTURE ACROSS THE FLORIDA
STRAITS AND INTO THE NORTHWEST BAHAMAS. IN ADDITION TROPICAL STORM
ERIKA CONTINUES TO MOVE WESTWARD TOWARD THE LEEWARD ISLANDS.
FOR TODAY AND THURSDAY...THE SURFACE TO LOW LEVEL SOUTHERLY WINDS
WILL ADVECT IN DEEPER TROPICAL MOISTURE INTO THE REGION TODAY
WHILE THE UPPER LEVEL TROUGH CONTINUES TO DEEPEN INTO THE GULF
WITH SOUTH FLORIDA EAST OF THE TROUGH AXIS. THE FORECAST SOUNDINGS
INDICATE REGIONAL PWATS AROUND 2.3 INCHES POSSIBLE TODAY WITH MID-
LEVEL TEMPERATURES DECREASING TO A DEGREE OR SO BELOW SEASONAL
NORMS. THE FORECAST SOUNDINGS ALSO INDICATE A LOCALLY UNSTABLE
ATMOSPHERE BY 18Z WITH FORECAST STABILITY INDICES INDICATING GOOD
POTENTIAL FOR CONVECTION. GIVEN ALL THESE FACTORS...SCATTERED TO
NUMEROUS AFTERNOON SHOWERS/THUNDERSTORMS ARE EXPECTED ACROSS SOUTH
FLORIDA WITH THE GREATEST COVERAGE IN THE INTERIOR REGIONS
ALTHOUGH THE WEST AND EAST COAST METRO AREAS COULD EXPERIENCE
WIDESPREAD ACTIVITY AS WELL IN ISOLATED AREAS. VERY SIMILAR CONDITIONS
ARE FORECAST FOR THURSDAY...WITH THE AXIS OF THE UPPER LEVEL LOW
STILL REMAINING IN THE NORTHERN TO CENTRAL GULF AND SOUTHERLY FLOW
CONTINUING TO BRING TROPICAL MOISTURE INTO THE REGION. THURSDAY`S
MID-LEVEL TEMPERATURES ARE FORECAST TO REMAIN COOLER THAN SEASONAL
NORMS...WITH SCATTERED TO NUMEROUS AFTERNOON SHOWERS/THUNDERSTORMS
WITH THE FOCUS AGAIN IN THE INTERIOR REGIONS AND CANNOT RULE OUT
ACTIVE PERIODS FOR THE METRO AREAS. ITS WORTH NOTING THAT COVERAGE
OF SHOWERS/THUNDERSTORMS IS EXPECTED TO INCREASE ACROSS THE
REGIONAL WATERS OF SOUTH FLORIDA DURING THIS PERIOD.
WITH REGARDS TO POSSIBLE IMPACTS FROM TROPICAL STORM ERIKA...THE
OFFICIAL NATIONAL HURRICANE CENTER FORECAST IS FOR ERIKA TO TRACK
WEST NORTHWEST OVER THE NEXT SEVERAL DAYS. THE CURRENT OFFICIAL
FORECAST HAS ERIKA REACHING THE SOUTHEASTERN BAHAMAS AS A TROPICAL
STORM BY SATURDAY EVENING AND INTO THE NORTHWEST BAHAMAS AS A
HURRICANE ON SUNDAY EVENING. THERE IS MUCH UNCERTAINTY WITH REGARD
TO THE TRACK AND INTENSITY OF ERIKA, SO THE EXTENDED FORECAST IS
HIGHLY UNCERTAIN. GIVEN THE UNCERTAINTIES...POTENTIAL IMPACTS MAY
NOT BE EXPECTED UNTIL LATE IN THE WEEKEND OR EARLY NEXT WEEK. ALL
INTERESTS IN SOUTH FLORIDA NEED TO CLOSELY MONITOR THE PROGRESS OF
TROPICAL STORM ERIKA AS IT TRACKS WEST NORTHWEST THE NEXT SEVERAL
DAYS.
MARINE...SOUTH TO SOUTHEASTERLY WINDS ARE FORECAST ACROSS THE
REGIONAL WATERS TODAY THROUGH FRIDAY AND GENERALLY AROUND 10 KNOTS
WITH REGIONAL SEAS 2 FEET OR LESS THROUGH THIS PERIOD. FOR THE
UPCOMING WEEKEND...ONCE AGAIN THERE IS CONSIDERABLE UNCERTAINTY
DUE TO POSSIBLE IMPACTS FROM TROPICAL STORM ERIKA. THE CURRENT
FORECAST HAS THE GREATEST IMPACTS LATE SUNDAY INTO MONDAY ACROSS
THE LOCAL ATLANTIC WATERS...BUT NEED TO STRESS AGAIN THE
CONSIDERABLE UNCERTAINTY.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 76 90 79 92 / 60 70 40 60
FORT LAUDERDALE 78 90 79 91 / 60 70 40 50
MIAMI 77 90 79 92 / 60 60 30 50
NAPLES 77 89 77 92 / 50 60 40 50
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AVIATION...10/CD
UPDATE...88/ALM
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
230 PM EDT WED AUG 26 2015
.SYNOPSIS...
A FRONTAL BOUNDARY WILL REMAIN STALLED JUST TO OUR SOUTH THROUGH
FRIDAY. INCREASING ATMOSPHERIC MOISTURE WILL DRIFT NORTH INTO OUR
REGION THIS WEEKEND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE UPPER TROUGH WILL REMAIN OVER THE EASTERN CONUS WITH
THE TROUGH AXIS WEST OF THE APPALACHIANS. A DIFFUSE FRONTAL
BOUNDARY WILL LINGER NEAR THE COAST WITH A WEAK WAVE OF LOW
PRESSURE OVER SOUTHEASTERN SOUTH CAROLINA. VISIBLE SATELLITE
DENOTED AN EAST/WEST BOUNDARY ACROSS THE SOUTHERN MIDLANDS AND CSRA.
DEWPOINTS WERE IN THE UPPER 50S AND LOWER 60S NORTH OF THE BOUNDARY
AND IN THE LOWER 70S TO THE SOUTH. PWAT VALUES RANGED FROM JUST
UNDER AN INCH ACROSS THE PIEDMONT AND CSRA TO 1.6 INCHES OVER THE
EASTERN MIDLANDS. INSTABILITY REMAINED WEAK ACROSS THE NORTHERN AND
CENTRAL MIDLANDS. WEAK TO MODERATE INSTABILITY WILL CONTINUE ACROSS
THE EASTERN AND SOUTHERN PORTION OF THE FORECAST AREA. WE KEPT A
SLIGHT CHANCE FOR A SHOWER OR THUNDERSTORM FOR THE EASTERN COUNTIES
WHERE MOISTURE AND INSTABILITY IS GREATEST. AFTERNOON HIGH
TEMPERATURES ARE FORECAST IN THE UPPER 80S TO LOWER 90S.
ANY LINGERING SHOWERS/STORMS EARLY THIS EVENING ACROSS THE EAST
ARE EXPECTED TO DISSIPATE RATHER QUICKLY BY MIDNIGHT...WITH
MAJORITY OF THE AREA DRY TONIGHT.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
MAIN UPPER TROUGH JUST TO OUR WEST WILL BEGIN GRADUALLY WEAKENING
AND LIFTING NORTH...BUT STILL LEAVING BEHIND A WEAK UPPER TROUGH
TO OUR WEST AND CUT OFF LOW IN THE GULF OF MEXICO...WHILE UPPER
RIDGE OVER THE WESTERN ATLANTIC BEGINS TO BUILD WESTWARD TOWARDS
THE SE COAST. SURFACE FRONT IS EXPECTED TO REMAIN NEARLY
STATIONARY NEAR THE COAST...WHILE SURFACE HIGH PRESSURE SHIFTS
EAST FROM THE MIDWEST INTO THE MID ATLANTIC....AND SURFACE WAVE
NEAR THE SC COAST SHIFTS SW TOWARDS THE GULF COAST. MODELS PROG
DRY AIR AT MID AND UPPER LEVELS TO REMAIN IN PLACE...WHILE LOW
LEVELS GRADUALLY MOISTEN OVER PORTIONS OF THE FORECAST AREA (FA)
DUE TO AN E TO NE LOW LEVEL FLOW OFF THE ATLANTIC.
HOWEVER...RELATIVELY DRY LOW LEVEL AIR MAY REMAIN ENTRENCHED
ACROSS THE NORTHERN FA AS SURFACE HIGH RIDGES FROM THE MID
ATLANTIC INTO THE WESTERN CAROLINAS. WEAK TO MODERATE MAINLY
DIURNAL INSTABILITY PROGGED. SLIGHT CHANCE TO LOW CHANCE POPS
APPEAR IN ORDER FAVORING THE SOUTHERN FA.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
SAT/SUN...MODELS INDICATE MAIN BELT OF UPPER WESTERLIES TO REMAIN
WELL TO THE NORTH WITH EMBEDDED SHORTWAVE SHIFTING EAST FROM THE
NORTHERN PLAINS INTO THE UPPER MIDWEST/GREAT LAKES REGION. THIS
ALONG WITH INDICATIONS OF WEAK UPPER TROUGHINESS REMAINING TO OUR
WEST....WITH SUBTROPICAL RIDGE REMAINING OVER THE WESTERN ATLANTIC
AND BUILDING TOWARDS THE SE COAST SOME...APPEARS TO DRAW MOISTURE
FROM THE GULF AND ATLANTIC NORTHWARD INTO OUR REGION. SO...WILL
MAINTAIN TREND TOWARDS INCREASING POPS FOR OUR REGION SAT/SUN.
ACCEPTED HPC GUIDANCE OF CHANCE TO POSSIBLY LOW END LIKELY POPS.
EARLY TO MID NEXT WEEK...MODELS GENERALLY MAINTAIN WEAK UPPER TROUGH
TO OUR WEST AND SUBTROPICAL UPPER RIDGE TO OUR SE. MAIN CONCERN FOR
THIS TIME PERIOD WILL BE TROPICAL CYCLONE ERIKA. LATEST OFFICIAL
FORECAST FROM NHC BRINGS IT NW ACROSS THE BAHAMAS AS A TROPICAL
STORM SUN/SUN NT THEN STRENGTHEN IT TO A LOW END HURRICANE AND
MOVING IT INTO S FL BY EARLY MONDAY. GENERAL MODEL CONSENSUS HAS IT
DRIFTING TO THE NORTH THEREAFTER. FOR NOW...DUE TO UNCERTAINITES
REGARDING IMPACT FOR OUR REGION...WILL MAINTAIN CHANCE POPS.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
VFR EXPECTED THROUGH THE AFTERNOON AND EVENING.
A NEARLY STATIONARY BOUNDARY WAS SOUTH AND EAST OF THE TAF SITES.
DRY AIR WILL CONTINUE OVER MUCH OF THE NORTHERN AND CENTRAL MIDLANDS
AS HIGH PRESSURE RIDGES IN FROM THE NORTHWEST. CANNOT RULE OUT
ISOLATED AFTERNOON/EVENING CONVECTION NEAR OGB...BUT CONFIDENCE TOO
LOW TO INCLUDE IN TAF GIVEN WEAK INSTABILITY AND MODEST MOISTURE.
AREAS OF LATE NIGHT FOG/STRATUS POSSIBLE TONIGHT. WENT WITH
PERSISTENCE FOR A PERIOD OF MVFR CIGS/VSBYS 06Z-14Z. BOTH THE NAM
AND RAP MODELS ALSO INDICATED LOW CLOUDS DEVELOPING LATE TONIGHT.
ANY FOG/STRATUS THAT DEVELOP SHOULD LIFT 14Z-16Z...WITH VFR
CONDITIONS RETURNING BY MIDDAY.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE IN MAINLY EARLY
MORNING FOG/STRATUS AND AFTERNOON AND EVENING ISOLATED TO
SCATTERED THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
713 AM EDT WED AUG 26 2015
.SYNOPSIS...
A WEAK COLD FRONT AND ASSOCIATED AREA OF LOW PRESSURE WILL STALL AND
DISSIPATE ALONG THE SOUTHEAST COAST THROUGH THURSDAY. HIGH PRESSURE
WILL SETTLE IN NORTH OF THE REGION INTO FRIDAY BEFORE MOVING OFF THE
EAST COAST THIS WEEKEND. ANOTHER AREA OF HIGH PRESSURE WILL BUILD
ACROSS THE SOUTHERN APPALACHIANS INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FOR THE SUNRISE UPDATE...SOME FAIRLY SIZABLE ADJUSTMENTS TO
HOURLY DEWPOINTS AND TEMPERATURES WERE MADE ACROSS THE WESTERN
TWO THIRDS OF THE FORECAST AREA AS THE FRONT HAS PUSHED A BIT
FARTHER EAST THAN EXPECTED. THE H3R AND RAP HAVE BACKED OFF
CONSIDERABLY FROM EARLIER RUNS ON THE AMOUNT OF SHOWERS/TSTMS WILL
DEVELOP OVER THE CHARLESTON TRI-COUNTY AREA DURING PEAK HEATING.
THIS IS A BIT PUZZLING GIVEN THE FAVORABLE ORIENTATION OF THE
COLD FRONT AND ITS LIKELY INTERACTIONS WITH THE SEA BREEZE
CIRCULATION. MAINTAINED POPS AS THEY WERE ADVERTISED EARLIER...BUT
IF THIS DRIER TREND CONTINUES...THEN LOWER POPS MAY BE NEEDED IN
SUBSEQUENT FORECAST UPDATES.
26/10Z SURFACE ANALYSIS PLACED 1010 MB LOW PRESSURE BETWEEN
MANNING AND GEORGETOWN WITH A QUASI-STATIONARY FRONT STRETCHING
FROM THE NORTH CAROLINA COASTAL PLAIN SOUTH THROUGH THE WESTERN
PEE DEE INTO THE FAR SOUTHERN MIDLANDS. THE BOUNDARY THEN ARCS
BACK TO SAVANNAH...JESUP AND INTO THE EASTERN FLORDIA PANHANDLE.
THE FRONT WILL MOVE LITTLE TODAY...ONLY INCHING EVER SO SLOWLY TO
THE EAST. THIS WILL KEEP AREAS ROUGHLY ALONG/EAST OF I-95 IN THE
CONCEPTUAL WARM SECTOR WITH THE FRONT ESSENTIALLY DELINEATING
DEWPOINTS IN THE LOWER-MID 70S FROM DEWPOINTS IN THE LOWER-MID
60S. ALOFT...A TROUGH OF LOW PRESSURE IS FORECAST TO DIG ACROSS
THE CENTRAL AND SOUTHERN APPALACHIANS THIS AFTERNOON AS 500 HPA
LOW PRESSURE TREKS NORTH OF THE GREAT LAKES.
A SLIGHT COOLING OF 500 HPA TEMPERATURES WILL TAKE PLACE BY MID
AFTERNOON AS THE MID-LEVEL TROUGH DRAWS CLOSER. THIS COUPLED WITH
MODERATE TO LOCALLY STRONG INSTABILITY AND SOME UPPER DIFLUENCE
INDUCED BY THE RIGHT ENTRANCE REGION OF THE UPPER JET OVER EASTERN
NORTH CAROLINA AND VIRGINIA WILL SUPPORT ISOLATED-SCATTERED
SHOWERS/TSTMS ACROSS EASTERN AREAS. ACTIVITY LOOKS TO BECOME
ENHANCED ACROSS THE CHARLESTON TRI-COUNTY AREA WHERE LOW-LEVEL
CONVERGENCE BECOMES MAXIMIZED NEAR THE SEA BREEZE/FRONTAL
INTERSECTION. SBCAPE IS FORECAST TO RISE TO 3200-3600 J/KG IN THIS
AREA PER KCHS MODIFIED RAP/NAM12 SOUNDINGS WITH DCAPE REACHING
1200-1500 J/KG. ALTHOUGH MID-LAPSE RATES ARE NOT OVERLY
COLD AND 0-6KM BULK SHEAR IS WEAK...THERE IS ENOUGH LOW-LEVEL
INSTABILITY AND DCAPE IN PLACE TO SUPPORT ISOLATED SEVERE
TSTMS...ESPECIALLY WHERE UPDRAFTS BECOME ENHANCED BY MESOSCALE
BOUNDARY COLLISIONS. LOCALLY DAMAGING WINDS AND CLOUD TO GROUND
LIGHTNING WILL BE PRIMARY HAZARDS.
20-50 PERCENT POPS LOOK FINE FOR AREAS ALONG/EAST OF THE I-95
CORRIDOR WITH THE HIGHEST POPS CENTERED OVER THE CHARLESTON TRI-
COUNTY AREA. LOCALLY HIGHER POPS MAY EVENTUALLY BE NEEDED AS
MESOSCALE TRENDS BECOME MORE APPARENT. FORECAST SOUNDINGS LOOK TOO
CAPPED TO SUPPORT MEASURABLE RAINFALL BEHIND THE FRONT AS
DEWPOINTS FALL INTO THE LOWER-MID 60S AND 700 HPA THETA-E LOWERS.
WILL MAINTAIN DRY CONDITIONS THERE...ROUGHLY ALONG/WEST OF A
HAMPTON-PEMBROKE-LUDOWICI LINE. HIGHS WILL BE FAIRLY UNIFORM
ACROSS THE FRONT...PEAKING IN THE LOWER 90 AWAY FROM THE BEACHES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
TONIGHT...THE FRONT WILL MOVE LITTLE OVERNIGHT AS LOW PRESSURE
MEANDERS TO THE SOUTHWEST ALONG THE BOUNDARY. THIS WILL KEEP MOST
OF SOUTHEAST SOUTH CAROLINA AND SOUTHEAST GEORGIA IN THE WARM
SECTOR WITH THE EXCEPTION OF FAR INTERIOR SOUTHEAST GEORGIA.
CONVECTION LOOKS DIE OFF RATHER QUICKLY THIS EVENING WITH THE
LOSS OF INSOLATION AND THE LOW-LEVEL CONVERGENCE MAXIMUM SHIFTING
BACK INTO THE COASTAL WATERS. SOME ISOLATED TO PERHAPS SCATTERED
CONVECTION MAY RE-FIRE ALONG THE BEACHES AND CHARLESTON TRI-COUNTY
AREA AFTER MIDNIGHT AS LOW-LEVEL CONVERGENCE RE- INTENSIFIES JUST
OFF THE LOWER SOUTH CAROLINA COAST. WILL KEEP 20/30 PERCENT POPS
IN PLACE ACROSS THE COASTAL ZONES TO ACCOUNT FOR THIS POSSIBILITY.
LOWS WILL RANGE FROM THE UPPER 60S/NEAR 70 ACROSS FAR INTERIOR
SOUTHEAST GEORGIA TO THE UPPER 70S/NEAR 80 AT THE BEACHES AND
DOWNTOWN CHARLESTON. THERE ARE SIGNALS THAT SOME POST-FRONTAL LOW
STRATUS AND POSSIBLY FOG COULD OOZE OUT OF THE PEE DEE AND EASTERN
MIDLANDS AND AFFECT THE INTERIOR SOUTH CAROLINA ZONES EARLY
TUESDAY MORNING. IT IS UNCLEAR ATTM WHETHER THIS WILL OCCUR...BUT
THIS WILL NEED TO BE WATCHED CAREFULLY.
THURSDAY AND FRIDAY...THE PERSISTENT UPPER TROUGH THAT HAS BEEN
ACROSS MUCH OF THE EASTERN U.S. WILL BEGIN TO WEAKEN AND MOVE WEST-
SOUTHWEST AS A DEEP LAYER ATLANTIC RIDGE ALSO STARTS TO BUILD FROM
THE EAST. AT THE SURFACE...HIGH PRESSURE BUILDS ACROSS THE NORTHEAST
AND THE MID ATLANTIC ON THURSDAY THEN SHIFTS OFF SHORE BY FRIDAY.
THE LOW LEVEL FLOW WILL START OFF EAST-NORTHEAST THURSDAY...VEERING
TO SOUTHEAST BY FRIDAY. DEEP LAYER MOISTURE WILL BE MARGINAL
THURSDAY...AND HAVE GONE LOW END CHANCE POPS ACROSS MUCH OF THE AREA
FOR AFTERNOON CONVECTION. BY FRIDAY...DEEP LAYER MOISTURE INCREASES
SLIGHTLY ALONG WITH THE CHANCES FOR CONVECTION. WITH LITTLE/NO UPPER
FORCING...EXPECT CONVECTION TO DIE DOWN IN THE EVENING BOTH
DAYS...BUT LEFT SLIGHT CHANCE TO LOW END CHANCE POPS CLOSER TO THE
COAST WITH ONSHORE FLOW BRINING IN MOISTURE AND THE POTENTIAL FOR
SHOWERS. HIGHS BOTH DAYS IN THE UPPER 80S TO AROUND 90...AND LOWS
IN THE LOWER TO MID 70S.
SATURDAY...THE SURFACE RIDGE CONTINUES TO PUSH EASTWARD OFF THE MID
ATLANTIC COAST WHILE THE UPPER RIDGE BUILDS WESTWARD FROM THE
ATLANTIC. THIS SETS UP A SOUTHEAST LOW LEVEL FLOW...WHICH ALSO HELPS
TO ADVECT IN BETTER DEEP LAYER MOISTURE. HAVE GONE CHANCE POPS
ENTIRE AREA...BUT WOULD NOT BE SURPRISED IF LATER FORECASTS RAISE
POPS FURTHER. HIGHS AGAIN IN THE UPPER 80S TO AROUND 90.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
THE PERIOD STARTS OFF WITH THE REGION BEING SQUEEZED BETWEEN A DEEP
LAYER ATLANTIC RIDGE CENTERED WELL EAST OF THE AREA AND AN UPPER
LEVEL TROUGH MOVING INTO THE OHIO AND TENNESSEE RIVER VALLEYS. THESE
TWO FEATURES HELP TO FOCUS SUFFICIENT DEEP LAYER MOISTURE ACROSS THE
REGION FOR SUNDAY. THIS MOISTURE...ALONG WITH SOME FORCING FROM THE
UPPER TROUGH TO THE NORTHWEST SHOULD RESULT IN SCATTERED CONVECTION
BY AFTERNOON. KEPT POPS CONSERVATIVE FOR IN THE MID TO HIGH END
CHANCE RANGE.
BY LATER SUNDAY AND BEYOND IS WHEN THE GLOBAL MODELS BEGIN TO REALLY
DIVERGE IN THE LARGE SCALE PATTERN. THE GFS WEAKENS THE UPPER TROUGH
TO THE NORTHWEST AND LEAVES THE AREA LARGELY DOMINATED BY ATLANTIC
HIGH PRESSURE THROUGH MID WEEK...WHILE THE ECMWF HOLDS ONTO THE
UPPER TROUGH TO THE NORTHWEST LONGER. THESE DIFFERENCES MAY BECOME
VERY IMPORTANT SINCE THEY WILL HAVE A LARGE INFLUENCE ON WHERE ERIKA
/OR THE REMNANTS OF/ TRACK. THE GFS CONTINUES TO SIGNIFICANTLY
WEAKEN THE CIRCULATION ASSOCIATED WITH ERIKA AND MOVES IT ACROSS
CUBA AND THE FLORIDA STRAIGHTS MONDAY AND TUESDAY...THEN LOSES IT
SOMEWHERE OVER NORTHERN FLORIDA AND OFF THE OUR ATLANTIC COAST BY
WEDNESDAY. THE ECMWF IS MUCH STRONGER WITH THE SYSTEM AND HAS A MORE
EASTERLY TRACK OVER THE FLORIDA PENINSULA EARLY NEXT WEEK THEN
STALLING OFF THE NORTHEAST FLORIDA COAST. THAT BEING SAID...WE WILL
CONTINUE TO MONITOR BOTH THE LATEST MODEL TRENDS CONCERNING THE FATE
OF ERIKA AS WELL AS OFFICIAL FORECASTS FROM THE NATIONAL HURRICANE
CENTER.
FOR NOW...GIVEN THE EXTREME UNCERTAINTY IN PATTERN...HAVE KEPT
CHANCES POPS FOR MUCH OF THE PERIOD WITH TEMPERATURES AROUND
NORMAL.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
VFR. MODELS ARE SHOWING A SIMILAR SIGNAL THAT SCATTERED TSTMS WILL
LIKELY IMPACT AREAS AROUND KCHS BY EARLY/MID AFTERNOON. TIMING IS
STILL A BIT IN QUESTION...BUT CONFIDENCE IS HIGH ENOUGH ATTM TO
INCLUDE A TEMPO GROUP FROM 19-22Z FOR 4SM -TSRA. TSTMS
PROBABILITIES ARE TOO LOW AT KSAV THIS FAR OUT TO INCLUDE A
MENTION FOR THE 06Z TAF CYCLE.
EXTENDED AVIATION OUTLOOK...THURSDAY AND FRIDAY...VFR WILL
DOMINATE WITH ISOLATED TO SCATTERED MAINLY AFTERNOON CONVECTION
WITH BRIEF FLIGHT RESTRICTIONS POSSIBLE.
SATURDAY AND SUNDAY...DEEP LAYER MOISTURE INCREASES AS AN UPPER
TROUGH BUILDS TO THE NORTHWEST AND CHANNELS MOISTURE NORTHWARD. THIS
SHOULD TRANSLATE TO HIGHER CHANCES FOR CONVECTION AND POTENTIAL FOR
BRIEF FLIGHT RESTRICTIONS.
EARLY TO MID NEXT WEEK...THERE CONTINUES TO BE LARGE DIFFERENCES IN
THE MODELS AS TO THE POTENTIAL TRACK AND STRENGTH OF WHAT IS
CURRENTLY ERIKA. FOR NOW EXPECT AT LEAST ISOLATED TO SCATTERED
CONVECTION MAINLY DURING THE AFTERNOON...BUT WILL CONTINUE TO
CLOSELY WATCH LATEST MODEL TRENDS AND OFFICIAL FORECASTS FROM THE
NATIONAL HURRICANE CENTER CONCERNING ERIKA.
&&
.MARINE...
TODAY...SOUTHWEST WINDS THIS MORNING WILL BACK SOUTH THIS
AFTERNOON AS A COLD FRONT APPROACHES THE COAST. LOCAL SEA BREEZE
ENHANCEMENTS ARE LIKELY...MAINLY NEAR THE LAND/SEA INTERFACE AND
CHARLESTON HARBOR. WINDS WILL HOLD AROUND 10 KT...LOCALLY HIGHER
NEAR THE COAST. SEAS WILL AVERAGE 2-3 FT...MAINLY COMPRISED 10-11
SECOND SWELL FROM THE EAST.
TONIGHT...A BIT OF A NOCTURNAL SURGE IS EXPECTED ACROSS THE
GEORGIA WATERS AS THE COLD FRONT HOLDS NEARLY STATIONARY. WINDS
ACROSS THE SOUTH CAROLINA WATERS WILL BE A BIT LIGHTER GIVEN THE
ORIENTATION OF THE LOW-LEVEL JET. EXPECT WINDS TO PEAK 15-20 KT
GEORGIA WATERS WITH 5-10 KT CHARLESTON COUNTY WATERS WITH 10-15 KT
BEAUFORT COUNTY WATERS. SEAS WILL HOLD 2-3 FT...MAINLY COMPRISED
OF 10-11 SECOND SWELL FROM THE EAST.
THURSDAY THROUGH MONDAY NIGHT...NO HIGHLIGHTS EXPECTED THROUGH
EARLY NEXT WEEK. HIGH PRESSURE WILL REMAIN NORTH OF THE WATERS
THROUGH SATURDAY WITH EAST- SOUTHEAST WINDS OF 15 KTS OR LESS AND
SEAS 3 FEET OR LESS. BY SUNDAY AND MONDAY...HIGH PRESSURE SHIFTS
FURTHER EAST OF THE AREA AND WINDS VEER TO SOUTHEAST TO
SOUTH...BUT REMAIN 15 KTS OR LESS AND SEAS 3 TO 4 FEET OR LESS.
THE BIG QUESTION AND UNCERTAINTY WITH THE LATER PART OF THE
FORECAST PERIOD AND INTO MID NEXT WEEK IS THE FATE OF ERIKA.
LATEST GLOBAL MODEL GUIDANCE CONTINUES TO DIFFER ON THE STRENGTH
AND EVENTUAL PATH. STAY TUNED TO THE LATEST FORECASTS FROM THE
NATIONAL HURRICANE CENTER CONCERNING ERIKA.
WATERSPOUTS...ATMOSPHERIC CONDITIONS ARE GENERALLY SUPPORTIVE OF
WATERSPOUTS THIS MORNING. THERE ARE HINTS IN THE RAP THAT A CLOUD
LINE OR LAND BREEZE CIRCULATION COULD DEVELOP OFF THE GEORGIA AND
FAR SOUTHERN SOUTH CAROLINA COAST AROUND SUNRISE...WHICH COULD
FOCUS THE WATERSPOUT POTENTIAL. WINDS ARE FORECAST TO BE A TAD TOO
HIGH FOR A MORE SIGNIFICANT RISK...BUT THE OVERALL ASSESSMENT POINTS
TO A MODERATE RISK FOR WATERSPOUTS. WILL INCLUDE A MENTION IN THE
HAZARDOUS WEATHER OUTLOOK. A MARINE WEATHER STATEMENT MAY ALSO BE
ISSUED IF THE FORMATION OF THE LAND BREEZE CIRCULATION OCCURS.
&&
.TIDES/COASTAL FLOODING...
CONTINUE TO MONITOR THE POTENTIAL FOR MINOR COASTAL FLOODING DURING
THE MAJOR HIGH TIDES THURSDAY THROUGH MID NEXT WEEK DUE TO ELEVATED
ASTRONOMICAL FROM THE UPCOMING PERIGEAN TIDES. THE LATEST EXTRA-
TROPICAL SURGE GUIDANCE ALREADY SHOWING MARGINAL COASTAL FLOODING
TIDE LEVELS FOR CHARLESTON THURSDAY THROUGH SATURDAY...AND VERY
CLOSE AT FORT PULASKI. THIS IS LIKELY DUE TO EASTERLY LOW LEVEL
WINDS THAT HELP INCREASE THE ALREADY HIGH TIDES. HARD TO TELL HOW
MUCH INFLUENCE THE LOW LEVEL WINDS WILL HAVE LATER THIS WEEKEND AND
INTO EARLY NEXT WEEK AS THERE IS CONSIDERABLE UNCERTAINTY WITH THE
TRACK AND INTENSITY OF ERIKA.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
ST/RFM
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
418 AM EDT WED AUG 26 2015
.SYNOPSIS...
A WEAK COLD FRONT AND ASSOCIATED AREA OF LOW PRESSURE WILL STALL AND
DISSIPATE ALONG THE SOUTHEAST COAST THROUGH THURSDAY. HIGH PRESSURE
WILL SETTLE IN NORTH OF THE REGION INTO FRIDAY BEFORE MOVING OFF THE
EAST COAST THIS WEEKEND. ANOTHER AREA OF HIGH PRESSURE WILL BUILD
ACROSS THE SOUTHERN APPALACHIANS INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
26/07Z SURFACE ANALYSIS PLACED 1011 MB LOW PRESSURE NEAR
MANNING...SOUTH CAROLINA WITH A STATIONARY FRONT EXTENDING FROM
THE COASTAL PLAIN OF NORTH CAROLINA THROUGH THE WESTERN PEE
DEE...INTO THE SOUTHERN MIDLANDS THEN TURNING SOUTH THROUGH
INTERIOR SOUTHEAST GEORGIA AND THE EASTERN FLORIDA PANHANDLE. THE
FRONT WILL MOVE LITTLE TODAY...ONLY INCHING EVER SO SLOWLY TO THE
EAST. THIS WILL KEEP AREAS ROUGHLY ALONG/EAST OF I-95 IN THE
CONCEPTUAL WARM SECTOR WITH THE FRONT ESSENTIALLY DELINEATING
DEWPOINTS IN THE LOWER-MID 70S FROM DEWPOINTS IN THE LOWER-MID
60S. ALOFT...A TROUGH OF LOW PRESSURE IS FORECAST TO DIG ACROSS
THE CENTRAL AND SOUTHERN APPALACHIANS THIS AFTERNOON AS 500 HPA
LOW PRESSURE TREKS NORTH OF THE GREAT LAKES.
A SLIGHT COOLING OF 500 HPA TEMPERATURES WILL TAKE PLACE BY MID
AFTERNOON AS THE MID-LEVEL TROUGH DRAWS CLOSER. THIS COUPLED WITH
MODERATE TO LOCALLY STRONG INSTABILITY AND SOME UPPER DIFLUENCE
INDUCED BY THE RIGHT ENTRANCE REGION OF THE UPPER JET OVER EASTERN
NORTH CAROLINA AND VIRGINIA WILL SUPPORT ISOLATED-SCATTERED
SHOWERS/TSTMS ACROSS EASTERN AREAS. ACTIVITY LOOKS TO BECOME
ENHANCED ACROSS THE CHARLESTON TRI-COUNTY AREA WHERE LOW-LEVEL
CONVERGENCE BECOMES MAXIMIZED NEAR THE SEA BREEZE/FRONTAL
INTERSECTION. SBCAPE IS FORECAST TO RISE TO 3200-3600 J/KG IN THIS
AREA PER KCHS MODIFIED RAP/NAM12 SOUNDINGS WITH DCAPE REACHING
1200-1500 J/KG. ALTHOUGH MID-LAPSE RATES ARE NOT OVERLY
COLD AND 0-6KM BULK SHEAR IS WEAK...THERE IS ENOUGH LOW-LEVEL
INSTABILITY AND DCAPE IN PLACE TO SUPPORT ISOLATED SEVERE
TSTMS...ESPECIALLY WHERE UPDRAFTS BECOME ENHANCED BY MESOSCALE
BOUNDARY COLLISIONS. LOCALLY DAMAGING WINDS AND CLOUD TO GROUND
LIGHTNING WILL BE PRIMARY HAZARDS.
20-50 PERCENT POPS LOOK FINE FOR AREAS ALONG/EAST OF THE I-95
CORRIDOR WITH THE HIGHEST POPS CENTERED OVER THE CHARLESTON TRI-
COUNTY AREA. LOCALLY HIGHER POPS MAY EVENTUALLY BE NEEDED AS
MESOSCALE TRENDS BECOME MORE APPARENT. FORECAST SOUNDINGS LOOK TOO
CAPPED TO SUPPORT MEASURABLE RAINFALL BEHIND THE FRONT AS
DEWPOINTS FALL INTO THE LOWER-MID 60S AND 700 HPA THETA-E LOWERS.
WILL MAINTAIN DRY CONDITIONS THERE...ROUGHLY ALONG/WEST OF A
HAMPTON-PEMBROKE-LUDOWICI LINE. HIGHS WILL BE FAIRLY UNIFORM
ACROSS THE FRONT...PEAKING IN THE LOWER 90 AWAY FROM THE BEACHES.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY/...
TONIGHT...THE FRONT WILL MOVE LITTLE OVERNIGHT AS LOW PRESSURE
MEANDERS TO THE SOUTHWEST ALONG THE BOUNDARY. THIS WILL KEEP MOST
OF SOUTHEAST SOUTH CAROLINA AND SOUTHEAST GEORGIA IN THE WARM
SECTOR WITH THE EXCEPTION OF FAR INTERIOR SOUTHEAST GEORGIA.
CONVECTION LOOKS DIE OFF RATHER QUICKLY THIS EVENING WITH THE
LOSS OF INSOLATION AND THE LOW-LEVEL CONVERGENCE MAXIMUM SHIFTING
BACK INTO THE COASTAL WATERS. SOME ISOLATED TO PERHAPS SCATTERED
CONVECTION MAY RE-FIRE ALONG THE BEACHES AND CHARLESTON TRI-COUNTY
AREA AFTER MIDNIGHT AS LOW-LEVEL CONVERGENCE RE- INTENSIFIES JUST
OFF THE LOWER SOUTH CAROLINA COAST. WILL KEEP 20/30 PERCENT POPS
IN PLACE ACROSS THE COASTAL ZONES TO ACCOUNT FOR THIS POSSIBILITY.
LOWS WILL RANGE FROM THE UPPER 60S/NEAR 70 ACROSS FAR INTERIOR
SOUTHEAST GEORGIA TO THE UPPER 70S/NEAR 80 AT THE BEACHES AND
DOWNTOWN CHARLESTON. THERE ARE SIGNALS THAT SOME POST-FRONTAL LOW
STRATUS AND POSSIBLY FOG COULD OOZE OUT OF THE PEE DEE AND EASTERN
MIDLANDS AND AFFECT THE INTERIOR SOUTH CAROLINA ZONES EARLY
TUESDAY MORNING. IT IS UNCLEAR ATTM WHETHER THIS WILL OCCUR...BUT
THIS WILL NEED TO BE WATCHED CAREFULLY.
THURSDAY AND FRIDAY...THE PERSISTENT UPPER TROUGH THAT HAS BEEN
ACROSS MUCH OF THE EASTERN U.S. WILL BEGIN TO WEAKEN AND MOVE WEST-
SOUTHWEST AS A DEEP LAYER ATLANTIC RIDGE ALSO STARTS TO BUILD FROM
THE EAST. AT THE SURFACE...HIGH PRESSURE BUILDS ACROSS THE NORTHEAST
AND THE MID ATLANTIC ON THURSDAY THEN SHIFTS OFF SHORE BY FRIDAY.
THE LOW LEVEL FLOW WILL START OFF EAST-NORTHEAST THURSDAY...VEERING
TO SOUTHEAST BY FRIDAY. DEEP LAYER MOISTURE WILL BE MARGINAL
THURSDAY...AND HAVE GONE LOW END CHANCE POPS ACROSS MUCH OF THE AREA
FOR AFTERNOON CONVECTION. BY FRIDAY...DEEP LAYER MOISTURE INCREASES
SLIGHTLY ALONG WITH THE CHANCES FOR CONVECTION. WITH LITTLE/NO UPPER
FORCING...EXPECT CONVECTION TO DIE DOWN IN THE EVENING BOTH
DAYS...BUT LEFT SLIGHT CHANCE TO LOW END CHANCE POPS CLOSER TO THE
COAST WITH ONSHORE FLOW BRINING IN MOISTURE AND THE POTENTIAL FOR
SHOWERS. HIGHS BOTH DAYS IN THE UPPER 80S TO AROUND 90...AND LOWS
IN THE LOWER TO MID 70S.
SATURDAY...THE SURFACE RIDGE CONTINUES TO PUSH EASTWARD OFF THE MID
ATLANTIC COAST WHILE THE UPPER RIDGE BUILDS WESTWARD FROM THE
ATLANTIC. THIS SETS UP A SOUTHEAST LOW LEVEL FLOW...WHICH ALSO HELPS
TO ADVECT IN BETTER DEEP LAYER MOISTURE. HAVE GONE CHANCE POPS
ENTIRE AREA...BUT WOULD NOT BE SURPRISED IF LATER FORECASTS RAISE
POPS FURTHER. HIGHS AGAIN IN THE UPPER 80S TO AROUND 90.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
THE PERIOD STARTS OFF WITH THE REGION BEING SQUEEZED BETWEEN A DEEP
LAYER ATLANTIC RIDGE CENTERED WELL EAST OF THE AREA AND AN UPPER
LEVEL TROUGH MOVING INTO THE OHIO AND TENNESSEE RIVER VALLEYS. THESE
TWO FEATURES HELP TO FOCUS SUFFICIENT DEEP LAYER MOISTURE ACROSS THE
REGION FOR SUNDAY. THIS MOISTURE...ALONG WITH SOME FORCING FROM THE
UPPER TROUGH TO THE NORTHWEST SHOULD RESULT IN SCATTERED CONVECTION
BY AFTERNOON. KEPT POPS CONSERVATIVE FOR IN THE MID TO HIGH END
CHANCE RANGE.
BY LATER SUNDAY AND BEYOND IS WHEN THE GLOBAL MODELS BEGIN TO REALLY
DIVERGE IN THE LARGE SCALE PATTERN. THE GFS WEAKENS THE UPPER TROUGH
TO THE NORTHWEST AND LEAVES THE AREA LARGELY DOMINATED BY ATLANTIC
HIGH PRESSURE THROUGH MID WEEK...WHILE THE ECMWF HOLDS ONTO THE
UPPER TROUGH TO THE NORTHWEST LONGER. THESE DIFFERENCES MAY BECOME
VERY IMPORTANT SINCE THEY WILL HAVE A LARGE INFLUENCE ON WHERE ERIKA
/OR THE REMNANTS OF/ TRACK. THE GFS CONTINUES TO SIGNIFICANTLY
WEAKEN THE CIRCULATION ASSOCIATED WITH ERIKA AND MOVES IT ACROSS
CUBA AND THE FLORIDA STRAIGHTS MONDAY AND TUESDAY...THEN LOSES IT
SOMEWHERE OVER NORTHERN FLORIDA AND OFF THE OUR ATLANTIC COAST BY
WEDNESDAY. THE ECMWF IS MUCH STRONGER WITH THE SYSTEM AND HAS A MORE
EASTERLY TRACK OVER THE FLORIDA PENINSULA EARLY NEXT WEEK THEN
STALLING OFF THE NORTHEAST FLORIDA COAST. THAT BEING SAID...WE WILL
CONTINUE TO MONITOR BOTH THE LATEST MODEL TRENDS CONCERNING THE FATE
OF ERIKA AS WELL AS OFFICIAL FORECASTS FROM THE NATIONAL HURRICANE
CENTER.
FOR NOW...GIVEN THE EXTREME UNCERTAINTY IN PATTERN...HAVE KEPT
CHANCES POPS FOR MUCH OF THE PERIOD WITH TEMPERATURES AROUND
NORMAL.
&&
.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
VFR. MODELS ARE SHOWING A SIMILAR SIGNAL THAT SCATTERED TSTMS WILL
LIKELY IMPACT AREAS AROUND KCHS BY EARLY/MID AFTERNOON. TIMING IS
STILL A BIT IN QUESTION...BUT CONFIDENCE IS HIGH ENOUGH ATTM TO
INCLUDE A TEMPO GROUP FROM 19-22Z FOR 4SM -TSRA. MAY NEED TO TWEAK
THE TIMES A BIT WITH THE 12Z TAF CYCLE. TSTMS PROBABILITIES ARE
TOO LOW AT KSAV THIS FAR OUT TO INCLUDE A MENTION FOR THE 06Z TAF
CYCLE.
EXTENDED AVIATION OUTLOOK...THURSDAY AND FRIDAY...VFR WILL
DOMINATE WITH ISOLATED TO SCATTERED MAINLY AFTERNOON CONVECTION
WITH BRIEF FLIGHT RESTRICTIONS POSSIBLE.
SATURDAY AND SUNDAY...DEEP LAYER MOISTURE INCREASES AS AN UPPER
TROUGH BUILDS TO THE NORTHWEST AND CHANNELS MOISTURE NORTHWARD. THIS
SHOULD TRANSLATE TO HIGHER CHANCES FOR CONVECTION AND POTENTIAL FOR
BRIEF FLIGHT RESTRICTIONS.
EARLY TO MID NEXT WEEK...THERE CONTINUES TO BE LARGE DIFFERENCES IN
THE MODELS AS TO THE POTENTIAL TRACK AND STRENGTH OF WHAT IS
CURRENTLY ERIKA. FOR NOW EXPECT AT LEAST ISOLATED TO SCATTERED
CONVECTION MAINLY DURING THE AFTERNOON...BUT WILL CONTINUE TO
CLOSELY WATCH LATEST MODEL TRENDS AND OFFICIAL FORECASTS FROM THE
NATIONAL HURRICANE CENTER CONCERNING ERIKA.
&&
.MARINE...
TODAY...SOUTHWEST WINDS THIS MORNING WILL BACK SOUTH THIS
AFTERNOON AS A COLD FRONT APPROACHES THE COAST. LOCAL SEA BREEZE
ENHANCEMENTS ARE LIKELY...MAINLY NEAR THE LAND/SEA INTERFACE AND
CHARLESTON HARBOR. WINDS WILL HOLD AROUND 10 KT...LOCALLY HIGHER
NEAR THE COAST. SEAS WILL AVERAGE 2-3 FT...MAINLY COMPRISED 10-11
SECOND SWELL FROM THE EAST.
TONIGHT...A BIT OF A NOCTURNAL SURGE IS EXPECTED ACROSS THE
GEORGIA WATERS AS THE COLD FRONT HOLDS NEARLY STATIONARY. WINDS
ACROSS THE SOUTH CAROLINA WATERS WILL BE A BIT LIGHTER GIVEN THE
ORIENTATION OF THE LOW-LEVEL JET. EXPECT WINDS TO PEAK 15-20 KT
GEORGIA WATERS WITH 5-10 KT CHARLESTON COUNTY WATERS WITH 10-15 KT
BEAUFORT COUNTY WATERS. SEAS WILL HOLD 2-3 FT...MAINLY COMPRISED
OF 10-11 SECOND SWELL FROM THE EAST.
THURSDAY THROUGH MONDAY NIGHT...NO HIGHLIGHTS EXPECTED THROUGH
EARLY NEXT WEEK. HIGH PRESSURE WILL REMAIN NORTH OF THE WATERS
THROUGH SATURDAY WITH EAST- SOUTHEAST WINDS OF 15 KTS OR LESS AND
SEAS 3 FEET OR LESS. BY SUNDAY AND MONDAY...HIGH PRESSURE SHIFTS
FURTHER EAST OF THE AREA AND WINDS VEER TO SOUTHEAST TO
SOUTH...BUT REMAIN 15 KTS OR LESS AND SEAS 3 TO 4 FEET OR LESS.
THE BIG QUESTION AND UNCERTAINTY WITH THE LATER PART OF THE
FORECAST PERIOD AND INTO MID NEXT WEEK IS THE FATE OF ERIKA.
LATEST GLOBAL MODEL GUIDANCE CONTINUES TO DIFFER ON THE STRENGTH
AND EVENTUAL PATH. STAY TUNED TO THE LATEST FORECASTS FROM THE
NATIONAL HURRICANE CENTER CONCERNING ERIKA.
WATERSPOUTS...ATMOSPHERIC CONDITIONS ARE GENERALLY SUPPORTIVE OF
WATERSPOUTS THIS MORNING. THERE ARE HINTS IN THE RAP THAT A CLOUD
LINE OR LAND BREEZE CIRCULATION COULD DEVELOP OFF THE GEORGIA AND
FAR SOUTHERN SOUTH CAROLINA COAST AROUND SUNRISE...WHICH COULD
FOCUS THE WATERSPOUT POTENTIAL. WINDS ARE FORECAST TO BE A TAD TOO
HIGH FOR A MORE SIGNIFICANT RISK...BUT THE OVERALL ASSESSMENT POINTS
TO A MODERATE RISK FOR WATERSPOUTS. WILL INCLUDE A MENTION IN THE
HAZARDOUS WEATHER OUTLOOK. A MARINE WEATHER STATEMENT MAY ALSO BE
ISSUED IF THE FORMATION OF THE LAND BREEZE CIRCULATION OCCURS.
&&
.TIDES/COASTAL FLOODING...
CONTINUE TO MONITOR THE POTENTIAL FOR MINOR COASTAL FLOODING DURING
THE MAJOR HIGH TIDES THURSDAY THROUGH MID NEXT WEEK DUE TO ELEVATED
ASTRONOMICAL FROM THE UPCOMING PERIGEAN TIDES. THE LATEST EXTRA-
TROPICAL SURGE GUIDANCE ALREADY SHOWING MARGINAL COASTAL FLOODING
TIDE LEVELS FOR CHARLESTON THURSDAY THROUGH SATURDAY...AND VERY
CLOSE AT FORT PULASKI. THIS IS LIKELY DUE TO EASTERLY LOW LEVEL
WINDS THAT HELP INCREASE THE ALREADY HIGH TIDES. HARD TO TELL HOW
MUCH INFLUENCE THE LOW LEVEL WINDS WILL HAVE LATER THIS WEEKEND AND
INTO EARLY NEXT WEEK AS THERE IS CONSIDERABLE UNCERTAINTY WITH THE
TRACK AND INTENSITY OF ERIKA.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
ST/RFM
AREA FORECAST DISCUSSION...CORRECTED
NWS LINCOLN IL
201 PM CDT WED AUG 26 2015
.SHORT TERM...(TONIGHT)
ISSUED AT 200 PM CDT WED AUG 26 2015
LARGE STRATOCUMULUS SHIELD THAT HAS PUSHED SOUTHWARD ACROSS THE
NORTHEAST QUARTER OF THE STATE WAS FINALLY STARTING TO SHOW SOME
CONTRACTION EARLY THIS AFTERNOON. HOWEVER...IT IS FLANKED ON MOST
SIDES BY DIURNAL DEVELOPMENT...SO NET RESULT CONTINUES TO BE QUITE A
BIT OF CLOUDS ESPECIALLY ACROSS THE EAST HALF OF THE CWA. THE 900 MB
PLOT OFF THE RAP MODEL CONTINUES TO DEPICT THE CLOUD SHIELD THE
BEST...AND SHOWS SOME CONTRACTION CONTINUING THIS AFTERNOON. MOST OF
THE DIURNAL CLOUDS SHOULD FADE WITH SUNSET. HOWEVER...SOME RESIDUAL
MOISTURE SHOULD LINGER FROM THE PERSISTENT CLOUDS...AND WILL GO WITH
PARTLY CLOUDY SKIES ACROSS THE NORTHEAST CORNER OF THE FORECAST AREA
NEAR DANVILLE AND CHAMPAIGN.
WITH HIGH PRESSURE OVERHEAD...ENOUGH CLEAR SKIES EXPECTED THAT MOST
AREAS SHOULD FALL INTO THE MID 50S OVERNIGHT. HOWEVER...SOME
ADJUSTMENTS MAY BE NEEDED ACROSS THE NORTHEAST IF THE CLOUDS DO NOT
CLEAR OUT FAST ENOUGH...AS HAS BEEN THE CASE THE LAST COUPLE NIGHTS.
&&
.LONG TERM...(THURSDAY THROUGH WEDNESDAY)
ISSUED AT 200 PM CDT WED AUG 26 2015
LATEST MODEL SOLUTIONS IN REASONABLE AGREEMENT FOR ILLINOIS OVER
THE REST OF THE WEEK. MODELS DIFFER IN STRENGTH AND MOISTURE
AVAILABILITY OF SOUTHERN STREAM WAVE CURRENTLY OVER FOUR CORNERS
AREA AND EXPECTED TO RIDE OVER RIDGE INTO ILLINOIS THIS WEEKEND.
WATER VAPOR IMAGERY SHOWS WAVE OVER NORTHERN ARIZONA THIS MORNING
PUSHING NORTHWARD OVER STRONG ROCKIES RIDGE. MODEL SUITE CONSISTENT
ON BRINGING ENERGY UP OVER THE RIDGE AND INTO MIDWEST FRIDAY AND
SATURDAY. UNTIL THEN...DRY CONDITIONS AND A WARMING TREND IS
EXPECTED AS 850 TEMPS CLIMB 5-10 DEGREES C BETWEEN THIS MORNINGS
RAOB AND FRIDAY EVENING. INCREASING HIGH CLOUDS AHEAD OF THE WAVE
MAY INHIBIT WARMING A BIT FOR FRIDAY...BUT TEMPS SHOULD STILL MAKE
IT INTO THE 80S THROUGHOUT FORECAST AREA BY FRIDAY AFTERNOON.
WAVE APPROACHING FOR THE FIRST PART OF THE WEEKEND IS MOVING INTO A
RELATIVELY DRY BUT MOISTENING AIRMASS. IN ADDITION...DIGGING OF
NORTHERN STREAM ENERGY ALONG THE WEST COAST SHOULD SLOW PROGRESSION
OF SYSTEMS AND THEREFORE SLOW THE INCOMING WAVE. CHANCE OF STORMS
ARE EXPECTED IN THE NORTHWEST BY LATE AFTERNOON FRIDAY AND ACROSS
MUCH OF THE AREA FRIDAY NIGHT AND PARTICULARLY SATURDAY. MAIN MODEL
DIFFERENCES BEGIN TO SHOW UP TOWARD THE END OF THE WEEKEND. LATEST
AVAILABLE ECMWF RUNS HAVE BEEN CONSISTENT ON BEING STRONG ENOUGH
WITH THIS WAVE TO DEVELOP DECENT NVA IN ITS WAKE ON SUNDAY AND
SHUNTING MOISTURE EAST OF THE AREA. THIS LEADS TO A RELATIVELY DRY
BUT INCREASINGLY HOT FORECAST AS THE LONGWAVE RIDGE AXIS MOVES
ACROSS THE AREA. MEANWHILE...THE 06Z AND 12Z GFS TRENDING WEAKER
WITH THE WAVE AND FORECAST AN EVOLUTION TO JUST A GENERAL WEAKNESS
OVER THE AREA THROUGH EARLY NEXT WEEK. THIS EVOLUTION SUGGESTS AT
LEAST A SLIGHT CHANCE OF THUNDERSTORMS AND LOWER TEMPERATURES
WITH GENERALLY MORE CLOUD COVER. AM LEANING TOWARD A COMPROMISE
WITH A NOD TOWARD THE GFS WHICH SEEMS TO BE SUPPORTED BY THE CMC
AND GEFS MEAN. A QUICK LOOK AT 12Z ECMWF ALSO SUGGESTS IT MAY BE
SWINGING BACK TOWARD A WEAKER SOLUTION.
ANY CONVECTION THAT DEVELOPS THIS WEEKEND INTO NEXT WEEK SHOULD HAVE
LIMITED SEVERE POTENTIAL DUE TO LOW SHEAR IN THE RIDGE AND LIMITED
INSTABILITY GIVEN THE WARM 500 MB TEMPS CLIMBING ABOVE -10C. BIGGEST
THREAT MAY BE LOCALLY HEAVY RAINFALL DUE TO SLOW MOVEMENT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1220 PM CDT WED AUG 26 2015
LARGE MVFR STRATOCUMULUS DECK CONTINUES TO EDGE SOUTHWARD...
HAVING CLIPPED KBMI AND IS COMING FAIRLY CLOSE TO KCMI AT MIDDAY.
LATEST RAP GUIDANCE DOES NOT SHOW A LOT MORE FURTHER PROGRESS.
HAVE MAINTAINED THE MVFR CONDITIONS AT KBMI AND INCLUDED A TEMPO
MVFR CEILING AT KCMI FOR THE NEXT FEW HOURS. TAF SITES FURTHER
WEST MAINLY BEING AFFECTED BY DIURNAL CUMULUS CLOSER TO 4000
FEET...AND THIS SHOULD FADE WITH SUNSET. VFR CONDITIONS EXPECTED
OVERNIGHT...WITH LIGHT WINDS GRADUALLY TRANSITIONING MORE TOWARD
THE SOUTHEAST AS AN AREA OF HIGH PRESSURE PASSES.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GEELHART
LONG TERM...BARKER
AVIATION...GEELHART
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1220 PM CDT WED AUG 26 2015
.UPDATE...
ISSUED AT 945 AM CDT WED AUG 26 2015
MAIN CONCERN IS WITH THE LOWER CLOUD DECK NUDGING SOUTHWARD.
LATEST VISIBLE SATELLITE IMAGERY SHOWS THIS CLOSE TO MOVING INTO
BLOOMINGTON...EXTENDING NORTHWARD THROUGH ROCKFORD AND THEN
EASTWARD. HRRR CLOUD GUIDANCE TRIES TO BREAK THIS UP OVER THE NEXT
COUPLE HOURS...BUT NOT REALLY SEEING ANY EVIDENCE OF THIS
YET...WITH THE CLOUD DECK RATHER SOLID UP INTO CENTRAL WISCONSIN.
RAP 900 MB HUMIDITY PLOT SHOWS THIS BETTER...AND STARTS MORE OF A
BREAKUP AFTER NOON. TIMING OF THE BREAKUP WILL IMPACT FORECAST
HIGHS...WHICH ARE IN THE MID 70S IN THAT AREA.
DID SOME ADJUSTMENTS OF THE CLOUD TRENDS ACROSS THE EASTERN
CWA...BUT NO CHANGES WERE NEEDED TO THE WORDED FORECASTS AT THIS
TIME.
&&
.SHORT TERM...(TODAY)
ISSUED AT 324 AM CDT WED AUG 26 2015
DEEP UPPER LOW NORTH OF LAKE ERIE EARLY THIS MORNING CONTINUES TO
SLOWLY EDGE AWAY FROM THE MIDWEST. HOWEVER, SEVERAL WEAK SHORTWAVES
CONTINUE TO ROTATE SOUTHWARD AROUND THE WESTERN PERIPHERY OF THE
UPPER LOW ACROSS THE LOWER GREAT LAKES BRINGING CLOUD COVER MUCH
FURTHER INTO OUR FORECAST AREA THAN WHAT GUIDANCE SUGGESTED. THAT
WILL BE THE MAIN FORECAST CONCERN TODAY, AMOUNT OF CLOUD COVER OVER
CENTRAL IL AND ITS AFFECT ON TEMPERATURES. RAP FORECAST SOUNDINGS
AND TIME HEIGHT CROSS SECTIONS SHOWING QUITE A BIT OF MOISTURE AT OR
JUST BELOW 850 MB INTO EARLY THIS AFTERNOON, ESPECIALLY OVER THE
EASTERN HALF OF THE FORECAST AREA. WILL HIT THE CLOUD COVER A BIT
HEAVIER ACROSS THE EAST TODAY WITH TEMPS CUT BACK A FEW DEGREES AS A
RESULT, MAINLY IN THE MID 70S, WHILE FURTHER WEST, A BIT MORE SUN
SHOULD ALLOW AFTERNOON TEMPERATURES TO RISE INTO THE UPPER 70S.
SOUNDINGS INDICATE SOME GUSTS UP TO 20 MPH POSSIBLE AGAIN FROM THE
NORTHWEST LATER THIS MORNING INTO THE AFTERNOON HOURS, ESPECIALLY
ACROSS THE WEST WHERE THERE WILL BE DEEPER MIXING OCCURRING.
.LONG TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 324 AM CDT WED AUG 26 2015
SLIGHTLY COOLER THAN CLIMATOLOGICAL NORMS THROUGH THE END OF THE
WEEK, ALBEIT IN A SLIGHT WARMING TREND. FORECAST ISSUE IN THE
LONGER TERM REMAINS THE SYSTEM FOR THE BEGINNING OF THE WEEKEND. A
SHORT WAVE DIVES INTO THE MIDWEST RIPPLING THROUGH THE
PREDOMINANTLY NWRLY FLOW. MODELS HAVE BEEN INCONSISTENT WITH THE
TIMING AND THE SPEED OF THE SYSTEM ITSELF WITH ITS OWN FORWARD
MOTION. WAVE REACHES THE MIDWEST AND SLOWS CONSIDERABLY. EITHER
WAY, SOME CONSENSUS APPEARS AS TO ONSET OF PRECIP IN CENTRAL
ILLINOIS AFTER 00Z SATURDAY BTWN THE GFS/ECMWF/NAM. HOWEVER, AT
THIS POINT, THE PRECIP STARTS TO BECOME LESS IN COVERAGE. EXPECTED
THROUGH THE OVERNIGHT FRI NIGHT PERHAPS WITH THE LOSS OF A DIURNAL
COMPONENT, BUT LESS EXPECTED DURING THE DAY ON TUESDAY. THAT BEING
SAID, THE SOUNDINGS ARE NOT REPRESENTATIVE FOR RAIN, DRYING OUT
CONSIDERABLY WHILE THE MODELS ARE GENERATING QPF. A RATHER DRY
AIRMASS FOR DAYS...THE MODELS SEEM TO BE OVERDOING THE BOUNDARY
LAYER AVAILABLE MOISTURE. OVERBLOWN RH IN THE LOW LEVELS IN THE
NAM IS EXPECTED AND SO FAR, IT IS TRUE TO FORM IN PRODUCING
SIGNIFICANTLY MORE QPF. THE TREND, THOUGH, IS MORE TO A POTENTIAL
SHOWERY SITUATION. HAVE EASED BACK POPS WHERE COLLABORATIVELY
POSSIBLE, AND SWITCHED THE WORDING TO COVERAGE INSTEAD OF
PROBABILITY.
BEYOND THE POPS ON THE WEEKEND, THE FLOW SWITCHES TO A LESS
AMPLIFIED PATTERN. THE WEAK SOUTHWESTERLY FLOW ALLOWS THE HEAT OVER
THE DESERT SW TO ESCAPE OUT FROM UNDER THE PERSISTENT RIDGE AND
BRING A WARMING TREND FOR THE FIRST COUPLE DAYS OF NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1220 PM CDT WED AUG 26 2015
LARGE MVFR STRATOCUMULUS DECK CONTINUES TO EDGE SOUTHWARD...
HAVING CLIPPED KBMI AND IS COMING FAIRLY CLOSE TO KCMI AT MIDDAY.
LATEST RAP GUIDANCE DOES NOT SHOW A LOT MORE FURTHER PROGRESS.
HAVE MAINTAINED THE MVFR CONDITIONS AT KBMI AND INCLUDED A TEMPO
MVFR CEILING AT KCMI FOR THE NEXT FEW HOURS. TAF SITES FURTHER
WEST MAINLY BEING AFFECTED BY DIURNAL CUMULUS CLOSER TO 4000
FEET...AND THIS SHOULD FADE WITH SUNSET. VFR CONDITIONS EXPECTED
OVERNIGHT...WITH LIGHT WINDS GRADUALLY TRANSITIONING MORE TOWARD
THE SOUTHEAST AS AN AREA OF HIGH PRESSURE PASSES.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEELHART
SHORT TERM...SMITH
LONG TERM...HJS
AVIATION...GEELHART
AREA FORECAST DISCUSSION
NWS LINCOLN IL
947 AM CDT WED AUG 26 2015
.UPDATE...
ISSUED AT 945 AM CDT WED AUG 26 2015
MAIN CONCERN IS WITH THE LOWER CLOUD DECK NUDGING SOUTHWARD.
LATEST VISIBLE SATELLITE IMAGERY SHOWS THIS CLOSE TO MOVING INTO
BLOOMINGTON...EXTENDING NORTHWARD THROUGH ROCKFORD AND THEN
EASTWARD. HRRR CLOUD GUIDANCE TRIES TO BREAK THIS UP OVER THE NEXT
COUPLE HOURS...BUT NOT REALLY SEEING ANY EVIDENCE OF THIS
YET...WITH THE CLOUD DECK RATHER SOLID UP INTO CENTRAL WISCONSIN.
RAP 900 MB HUMIDITY PLOT SHOWS THIS BETTER...AND STARTS MORE OF A
BREAKUP AFTER NOON. TIMING OF THE BREAKUP WILL IMPACT FORECAST
HIGHS...WHICH ARE IN THE MID 70S IN THAT AREA.
DID SOME ADJUSTMENTS OF THE CLOUD TRENDS ACROSS THE EASTERN
CWA...BUT NO CHANGES WERE NEEDED TO THE WORDED FORECASTS AT THIS
TIME.
&&
.SHORT TERM...(TODAY)
ISSUED AT 324 AM CDT WED AUG 26 2015
DEEP UPPER LOW NORTH OF LAKE ERIE EARLY THIS MORNING CONTINUES TO
SLOWLY EDGE AWAY FROM THE MIDWEST. HOWEVER, SEVERAL WEAK SHORTWAVES
CONTINUE TO ROTATE SOUTHWARD AROUND THE WESTERN PERIPHERY OF THE
UPPER LOW ACROSS THE LOWER GREAT LAKES BRINGING CLOUD COVER MUCH
FURTHER INTO OUR FORECAST AREA THAN WHAT GUIDANCE SUGGESTED. THAT
WILL BE THE MAIN FORECAST CONCERN TODAY, AMOUNT OF CLOUD COVER OVER
CENTRAL IL AND ITS AFFECT ON TEMPERATURES. RAP FORECAST SOUNDINGS
AND TIME HEIGHT CROSS SECTIONS SHOWING QUITE A BIT OF MOISTURE AT OR
JUST BELOW 850 MB INTO EARLY THIS AFTERNOON, ESPECIALLY OVER THE
EASTERN HALF OF THE FORECAST AREA. WILL HIT THE CLOUD COVER A BIT
HEAVIER ACROSS THE EAST TODAY WITH TEMPS CUT BACK A FEW DEGREES AS A
RESULT, MAINLY IN THE MID 70S, WHILE FURTHER WEST, A BIT MORE SUN
SHOULD ALLOW AFTERNOON TEMPERATURES TO RISE INTO THE UPPER 70S.
SOUNDINGS INDICATE SOME GUSTS UP TO 20 MPH POSSIBLE AGAIN FROM THE
NORTHWEST LATER THIS MORNING INTO THE AFTERNOON HOURS, ESPECIALLY
ACROSS THE WEST WHERE THERE WILL BE DEEPER MIXING OCCURRING.
.LONG TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 324 AM CDT WED AUG 26 2015
SLIGHTLY COOLER THAN CLIMATOLOGICAL NORMS THROUGH THE END OF THE
WEEK, ALBEIT IN A SLIGHT WARMING TREND. FORECAST ISSUE IN THE
LONGER TERM REMAINS THE SYSTEM FOR THE BEGINNING OF THE WEEKEND. A
SHORT WAVE DIVES INTO THE MIDWEST RIPPLING THROUGH THE
PREDOMINANTLY NWRLY FLOW. MODELS HAVE BEEN INCONSISTENT WITH THE
TIMING AND THE SPEED OF THE SYSTEM ITSELF WITH ITS OWN FORWARD
MOTION. WAVE REACHES THE MIDWEST AND SLOWS CONSIDERABLY. EITHER
WAY, SOME CONSENSUS APPEARS AS TO ONSET OF PRECIP IN CENTRAL
ILLINOIS AFTER 00Z SATURDAY BTWN THE GFS/ECMWF/NAM. HOWEVER, AT
THIS POINT, THE PRECIP STARTS TO BECOME LESS IN COVERAGE. EXPECTED
THROUGH THE OVERNIGHT FRI NIGHT PERHAPS WITH THE LOSS OF A DIURNAL
COMPONENT, BUT LESS EXPECTED DURING THE DAY ON TUESDAY. THAT BEING
SAID, THE SOUNDINGS ARE NOT REPRESENTATIVE FOR RAIN, DRYING OUT
CONSIDERABLY WHILE THE MODELS ARE GENERATING QPF. A RATHER DRY
AIRMASS FOR DAYS...THE MODELS SEEM TO BE OVERDOING THE BOUNDARY
LAYER AVAILABLE MOISTURE. OVERBLOWN RH IN THE LOW LEVELS IN THE
NAM IS EXPECTED AND SO FAR, IT IS TRUE TO FORM IN PRODUCING
SIGNIFICANTLY MORE QPF. THE TREND, THOUGH, IS MORE TO A POTENTIAL
SHOWERY SITUATION. HAVE EASED BACK POPS WHERE COLLABORATIVELY
POSSIBLE, AND SWITCHED THE WORDING TO COVERAGE INSTEAD OF
PROBABILITY.
BEYOND THE POPS ON THE WEEKEND, THE FLOW SWITCHES TO A LESS
AMPLIFIED PATTERN. THE WEAK SOUTHWESTERLY FLOW ALLOWS THE HEAT OVER
THE DESERT SW TO ESCAPE OUT FROM UNDER THE PERSISTENT RIDGE AND
BRING A WARMING TREND FOR THE FIRST COUPLE DAYS OF NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 625 AM CDT WED AUG 26 2015
MAIN CHALLENGE THIS PERIOD WILL BE WITH EXTENT OF CLOUD COVER
MAINLY ACROSS THE EASTERN TAF SITES. A BAND OF LOW VFR WITH
A FEW AREAS OF MVFR CIGS WAS LOCATED JUST TO OUR NORTH THIS
MORNING WITH A SOUTHWARD DRIFT IN THE CLOUD BAND. WILL CARRY
CIGS IN THE 3000-4000 FOOT RANGE FROM BMI SOUTH TOWARDS DEC
OVER TO CMI THIS MORNING WHICH SHOULD CONTINUE INTO THE MID
AFTERNOON HOURS BEFORE COVERAGE DECREASES. SURFACE WINDS WILL
BE OUT OF THE NORTH AT 10 TO 15 KTS...WITH A FEW GUSTS POSSIBLE
THIS AFTERNOON AT SPI WHERE WE SHOULD SEE SOME BETTER MIXING DUE
TO MORE SUNSHINE COMPARED TO THE TAF SITES FURTHER TO THE EAST.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEELHART
SHORT TERM...SMITH
LONG TERM...HJS
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS LINCOLN IL
626 AM CDT WED AUG 26 2015
.SHORT TERM...(TODAY)
ISSUED AT 324 AM CDT WED AUG 26 2015
DEEP UPPER LOW NORTH OF LAKE ERIE EARLY THIS MORNING CONTINUES TO
SLOWLY EDGE AWAY FROM THE MIDWEST. HOWEVER, SEVERAL WEAK SHORTWAVES
CONTINUE TO ROTATE SOUTHWARD AROUND THE WESTERN PERIPHERY OF THE
UPPER LOW ACROSS THE LOWER GREAT LAKES BRINGING CLOUD COVER MUCH
FURTHER INTO OUR FORECAST AREA THAN WHAT GUIDANCE SUGGESTED. THAT
WILL BE THE MAIN FORECAST CONCERN TODAY, AMOUNT OF CLOUD COVER OVER
CENTRAL IL AND ITS AFFECT ON TEMPERATURES. RAP FORECAST SOUNDINGS
AND TIME HEIGHT CROSS SECTIONS SHOWING QUITE A BIT OF MOISTURE AT OR
JUST BELOW 850 MB INTO EARLY THIS AFTERNOON, ESPECIALLY OVER THE
EASTERN HALF OF THE FORECAST AREA. WILL HIT THE CLOUD COVER A BIT
HEAVIER ACROSS THE EAST TODAY WITH TEMPS CUT BACK A FEW DEGREES AS A
RESULT, MAINLY IN THE MID 70S, WHILE FURTHER WEST, A BIT MORE SUN
SHOULD ALLOW AFTERNOON TEMPERATURES TO RISE INTO THE UPPER 70S.
SOUNDINGS INDICATE SOME GUSTS UP TO 20 MPH POSSIBLE AGAIN FROM THE
NORTHWEST LATER THIS MORNING INTO THE AFTERNOON HOURS, ESPECIALLY
ACROSS THE WEST WHERE THERE WILL BE DEEPER MIXING OCCURRING.
.LONG TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 324 AM CDT WED AUG 26 2015
SLIGHTLY COOLER THAN CLIMATOLOGICAL NORMS THROUGH THE END OF THE
WEEK, ALBEIT IN A SLIGHT WARMING TREND. FORECAST ISSUE IN THE
LONGER TERM REMAINS THE SYSTEM FOR THE BEGINNING OF THE WEEKEND. A
SHORT WAVE DIVES INTO THE MIDWEST RIPPLING THROUGH THE
PREDOMINANTLY NWRLY FLOW. MODELS HAVE BEEN INCONSISTENT WITH THE
TIMING AND THE SPEED OF THE SYSTEM ITSELF WITH ITS OWN FORWARD
MOTION. WAVE REACHES THE MIDWEST AND SLOWS CONSIDERABLY. EITHER
WAY, SOME CONSENSUS APPEARS AS TO ONSET OF PRECIP IN CENTRAL
ILLINOIS AFTER 00Z SATURDAY BTWN THE GFS/ECMWF/NAM. HOWEVER, AT
THIS POINT, THE PRECIP STARTS TO BECOME LESS IN COVERAGE. EXPECTED
THROUGH THE OVERNIGHT FRI NIGHT PERHAPS WITH THE LOSS OF A DIURNAL
COMPONENT, BUT LESS EXPECTED DURING THE DAY ON TUESDAY. THAT BEING
SAID, THE SOUNDINGS ARE NOT REPRESENTATIVE FOR RAIN, DRYING OUT
CONSIDERABLY WHILE THE MODELS ARE GENERATING QPF. A RATHER DRY
AIRMASS FOR DAYS...THE MODELS SEEM TO BE OVERDOING THE BOUNDARY
LAYER AVAILABLE MOISTURE. OVERBLOWN RH IN THE LOW LEVELS IN THE
NAM IS EXPECTED AND SO FAR, IT IS TRUE TO FORM IN PRODUCING
SIGNIFICANTLY MORE QPF. THE TREND, THOUGH, IS MORE TO A POTENTIAL
SHOWERY SITUATION. HAVE EASED BACK POPS WHERE COLLABORATIVELY
POSSIBLE, AND SWITCHED THE WORDING TO COVERAGE INSTEAD OF
PROBABILITY.
BEYOND THE POPS ON THE WEEKEND, THE FLOW SWITCHES TO A LESS
AMPLIFIED PATTERN. THE WEAK SOUTHWESTERLY FLOW ALLOWS THE HEAT OVER
THE DESERT SW TO ESCAPE OUT FROM UNDER THE PERSISTENT RIDGE AND
BRING A WARMING TREND FOR THE FIRST COUPLE DAYS OF NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 625 AM CDT WED AUG 26 2015
MAIN CHALLENGE THIS PERIOD WILL BE WITH EXTENT OF CLOUD COVER
MAINLY ACROSS THE EASTERN TAF SITES. A BAND OF LOW VFR WITH
A FEW AREAS OF MVFR CIGS WAS LOCATED JUST TO OUR NORTH THIS
MORNING WITH A SOUTHWARD DRIFT IN THE CLOUD BAND. WILL CARRY
CIGS IN THE 3000-4000 FOOT RANGE FROM BMI SOUTH TOWARDS DEC
OVER TO CMI THIS MORNING WHICH SHOULD CONTINUE INTO THE MID
AFTERNOON HOURS BEFORE COVERAGE DECREASES. SURFACE WINDS WILL
BE OUT OF THE NORTH AT 10 TO 15 KTS...WITH A FEW GUSTS POSSIBLE
THIS AFTERNOON AT SPI WHERE WE SHOULD SEE SOME BETTER MIXING DUE
TO MORE SUNSHINE COMPARED TO THE TAF SITES FURTHER TO THE EAST.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...SMITH
LONG TERM...HJS
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS LINCOLN IL
325 AM CDT WED AUG 26 2015
.SHORT TERM...(TODAY)
ISSUED AT 324 AM CDT WED AUG 26 2015
DEEP UPPER LOW NORTH OF LAKE ERIE EARLY THIS MORNING CONTINUES TO
SLOWLY EDGE AWAY FROM THE MIDWEST. HOWEVER, SEVERAL WEAK SHORTWAVES
CONTINUE TO ROTATE SOUTHWARD AROUND THE WESTERN PERIPHERY OF THE
UPPER LOW ACROSS THE LOWER GREAT LAKES BRINGING CLOUD COVER MUCH
FURTHER INTO OUR FORECAST AREA THAN WHAT GUIDANCE SUGGESTED. THAT
WILL BE THE MAIN FORECAST CONCERN TODAY, AMOUNT OF CLOUD COVER OVER
CENTRAL IL AND ITS AFFECT ON TEMPERATURES. RAP FORECAST SOUNDINGS
AND TIME HEIGHT CROSS SECTIONS SHOWING QUITE A BIT OF MOISTURE AT OR
JUST BELOW 850 MB INTO EARLY THIS AFTERNOON, ESPECIALLY OVER THE
EASTERN HALF OF THE FORECAST AREA. WILL HIT THE CLOUD COVER A BIT
HEAVIER ACROSS THE EAST TODAY WITH TEMPS CUT BACK A FEW DEGREES AS A
RESULT, MAINLY IN THE MID 70S, WHILE FURTHER WEST, A BIT MORE SUN
SHOULD ALLOW AFTERNOON TEMPERATURES TO RISE INTO THE UPPER 70S.
SOUNDINGS INDICATE SOME GUSTS UP TO 20 MPH POSSIBLE AGAIN FROM THE
NORTHWEST LATER THIS MORNING INTO THE AFTERNOON HOURS, ESPECIALLY
ACROSS THE WEST WHERE THERE WILL BE DEEPER MIXING OCCURRING.
&&
.LONG TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 324 AM CDT WED AUG 26 2015
SLIGHTLY COOLER THAN CLIMATOLOGICAL NORMS THROUGH THE END OF THE
WEEK, ALBEIT IN A SLIGHT WARMING TREND. FORECAST ISSUE IN THE
LONGER TERM REMAINS THE SYSTEM FOR THE BEGINNING OF THE WEEKEND. A
SHORT WAVE DIVES INTO THE MIDWEST RIPPLING THROUGH THE
PREDOMINANTLY NWRLY FLOW. MODELS HAVE BEEN INCONSISTENT WITH THE
TIMING AND THE SPEED OF THE SYSTEM ITSELF WITH ITS OWN FORWARD
MOTION. WAVE REACHES THE MIDWEST AND SLOWS CONSIDERABLY. EITHER
WAY, SOME CONSENSUS APPEARS AS TO ONSET OF PRECIP IN CENTRAL
ILLINOIS AFTER 00Z SATURDAY BTWN THE GFS/ECMWF/NAM. HOWEVER, AT
THIS POINT, THE PRECIP STARTS TO BECOME LESS IN COVERAGE. EXPECTED
THROUGH THE OVERNIGHT FRI NIGHT PERHAPS WITH THE LOSS OF A DIURNAL
COMPONENT, BUT LESS EXPECTED DURING THE DAY ON TUESDAY. THAT BEING
SAID, THE SOUNDINGS ARE NOT REPRESENTATIVE FOR RAIN, DRYING OUT
CONSIDERABLY WHILE THE MODELS ARE GENERATING QPF. A RATHER DRY
AIRMASS FOR DAYS...THE MODELS SEEM TO BE OVERDOING THE BOUNDARY
LAYER AVAILABLE MOISTURE. OVERBLOWN RH IN THE LOW LEVELS IN THE
NAM IS EXPECTED AND SO FAR, IT IS TRUE TO FORM IN PRODUCING
SIGNIFICANTLY MORE QPF. THE TREND, THOUGH, IS MORE TO A POTENTIAL
SHOWERY SITUATION. HAVE EASED BACK POPS WHERE COLLABORATIVELY
POSSIBLE, AND SWITCHED THE WORDING TO COVERAGE INSTEAD OF
PROBABILITY.
BEYOND THE POPS ON THE WEEKEND, THE FLOW SWITCHES TO A LESS
AMPLIFIED PATTERN. THE WEAK SOUTHWESTERLY FLOW ALLOWS THE HEAT OVER
THE DESERT SW TO ESCAPE OUT FROM UNDER THE PERSISTENT RIDGE AND
BRING A WARMING TREND FOR THE FIRST COUPLE DAYS OF NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1142 PM CDT TUE AUG 25 2015
QUIET/VFR AVIATION WEATHER CONDITIONS EXPECTED ACROSS THE CENTRAL
ILLINOIS TERMINALS THROUGH THE 06Z TAF VALID TIME. A RIDGE OF
HIGH PRESSURE WILL SLOWLY BUILD INTO THE AREA DURING THE PERIOD
HELPING WINDS TO REMAIN LIGHT. CLOUD COVER SHOULD BE MINIMAL
OVERALL, BUT A PERIOD OF BROKEN VFR CIGS IS POSSIBLE FOR A FEW
MORE HOURS KPIA, KBMI, KDEC & KCMI AS AN UPPER LEVEL DISTURBANCE
DIVES SOUTHEAST FROM THE GREAT LAKES.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...SMITH
LONG TERM...HJS
AVIATION...BAK
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
614 PM CDT THU AUG 27 2015
...Updated for Aviation...
.SHORT TERM...(THIS EVENING THROUGH Friday)
ISSUED AT 117 PM CDT THU AUG 27 2015
Models remain in good agreement with an upper level trough
crossing the Central High Plains overnight as a surface
boundary/weak cold front crosses southwestern Kansas. Water vapor
loop earlier this morning indicated an upper level disturbance,
located over southern Colorado at 12z Thursday. Dprog/dt along
with the RAP and NAM suggesting that this disturbance will precede
the main upper trough and will be crossing southwest Kansas
between 18z Thursday and 00z Friday. Based on the timing of the
southern Colorado upper wave along with 700mb moisture, 700mb
frontogenesis, and afternoon mid level instability ahead of this
wave late day will be leaning towards the HRRR,RAP,ARW, and NMM
with the better chances for scattered thunderstorms developing
along and east of a Dighton to Hugoton line. the main hazards from
these storms still appear to be hail quarter size and smaller
along with wind gusts of near 60 mph based on the latest RAP 0-6km
shear and CAPE values late today and early this evening. Periods
of moderate to heavy rainfall will also be possible, especially
east of highway 283. These thunderstorms are expected to move east
overnight as another area of scattered thunderstorms develop
further west near the weak cold front/surface boundary as it and
the main upper trough crosses western Kansas between 03z and 12z
Friday. Severe weather is not anticipated with these storms,
however moderate rainfall and lightning still will be likely.
A few lingering thunderstorms will be possible across south
central Kansas early Friday morning, however as the upper level
trough moves east towards the mid Mississippi valley these storms
will quickly end and skies will begin to clear from west to east.
As the weak cold front continues to move south across Oklahoma
during the day the 900mb to 850mb temperatures will cool. 850mb
mix down temperatures at 00z Saturday continue to supports highs
mainly in the 85 to 90 degree range.
.LONG TERM...(Friday NIGHT THROUGH Thursday)
ISSUED AT 240 PM CDT THU AUG 27 2015
High pressure at the surface will build across western Kansas
Friday night so winds will decrease to less than 10 knots after
sunset. Given these winds and clear/mostly clear conditions will
trend towards undercutting guidance for lows. Will favor
temperatures falling back into the mainly the upper 50s to lower
60s.
From Saturday through the beginning of next week an upper level
ridge will build and shift eastward into the Central and Northern
Plains. This trend continues to support the previous forecast with
a gradual warming trend through early next week. Highs will be
rebounding from the upper 80s to around 90 on Saturday to at least
the low to mid 90s on Monday and Tuesday.
Towards mid week a southwesterly flow will develop across the
Central High Plains. The GFS and ECMWF also suggest some tropical
moisture will try to return to Colorado and portions of western
Kansas. This may limit how warm temperatures will get around mid
week. There will also be a slightly better chance for afternoon
and evening thunderstorms along a surface boundary which is
expected to be located near the Colorado border should any subtle
upper wave be embedded in the southwesterly flow.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z Friday EVENING)
ISSUED AT 609 PM CDT THU AUG 27 2015
VFR conditions are expected. A shortwave trough will move through
western KS tonight with strong storms staying mainly east and
south of the TAF sites. South winds of 15-25kt will decrease by
03z, then switch to the north or become light and variable mainly
after 06Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 66 88 60 89 / 40 10 0 0
GCK 64 88 59 89 / 30 10 0 0
EHA 64 88 59 89 / 30 10 10 0
LBL 66 89 60 90 / 40 10 0 0
HYS 65 87 59 89 / 50 10 0 0
P28 70 91 63 90 / 20 20 10 0
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Burgert
LONG TERM...Burgert
AVIATION...Kruse
AREA FORECAST DISCUSSION
NWS GOODLAND KS
448 PM MDT WED AUG 26 2015
.UPDATE...
ISSUED AT 443 PM MDT WED AUG 26 2015
INSERTED SLIGHT CHANCE POPS ALONG AND EAST OF AN IMPERIAL NE TO
HILL CITY KS LINE FOR THE LATE AFTERNOON AND EARLY EVENING HOURS.
ISOLATED STORM POPPED UP ALONG RETREATING FRONTAL BOUNDARY NEAR
KHLC WHERE DEW POINTS REMAIN IN THE UPPER 50S TO LOWER 60S. STORMS
WILL DISSIPATE WITH LOSS OF SURFACE HEATING AFTER SUNSET. DEEP
LAYER SHEAR AND INSTABILITY SUPPORT AN ISOLATED SEVERE THREAT FOR
HAIL...BUT COVERAGE WILL BE QUITE LIMITED DUE TO LACK OF UPPER
FORCING.
ALSO INCREASED CLOUDINESS WITH COPIOUS MID/HIGH LEVEL CLOUDS
OVERSPREADING THE AREA FROM THE WEST.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 110 PM MDT WED AUG 26 2015
WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS RIDGE IN PLACE ACROSS
THE PLAINS WITH 596 DM CENTER AXIS EXTENDING NORTH OVER OUR CWA.
SHORTWAVE TROUGH IS CURRENTLY ROTATING AROUND WESTERN EDGE OF RIDGE
WITH MOISTURE PLUME EXTENDING ACROSS THE CENTRAL ROCKIES AHEAD OF
THIS FEATURE. AT THE SURFACE LO PRESSURE EXTENDS FROM EASTERN
MONTANA ACROSS EASTERN COLORADO AND OVER OUR CWA. A WEAK
STATIONARY FRONT IS CURRENTLY IN PLACE FROM SW NEBRASKA AND ACROSS
CENTRAL KANSAS (NEAR HLC).
THIS AFTERNOON-TONIGHT...VERY DRY AIR MASS...STRONG CAP...AND
LIMITED LARGE SCALE FORCING WILL CONTINUE TO LIMIT CONVECTIVE
POTENTIAL. CAP MAY BEGIN TO WEAKEN ALONG STALLED FRONT IN OUR
EASTERN CWA LATER THIS AFTERNOON...HOWEVER AT THIS POINT
CONFIDENCE IS TOO LOW TO INCLUDE A MENTION OF
SHOWERS/THUNDERSTORMS. AS WAS EXPECTED HOT TEMPERATURES AND
FAVORABLE MIXING HAVE RESULTED IN VERY LOW RH VALUES THIS
AFTERNOON ACROSS THE WESTERN HALF OF OF OUR FORECAST AREA...WITH
SOME LOCATIONS GUSTING TO NEAR RFW CRITERIA. WITH FUELS STILL NOT
CONSIDERED FAVORABLE FOR RAPID FIRE SPREAD I HAVE HELD BACK ON RFW
ISSUANCE.
THURSDAY...UPPER LEVEL TROUGH WILL ROTATE AROUND THE NORTH SIDE OF
THE RIDGE AND DEEPEN AS IT TRACKS ACROSS THE NORTHERN PLAINS.
LARGE SCALE FORCING WILL OVERSPREAD OUR CWA ON THE SOUTHERN EXTENT
OF THIS FEATURE...WITH DRY AIR MASS INITIALLY LIMITING CONVECTIVE
COVERAGE UNTIL LATER THURSDAY AFTERNOON. RETURN FLOW AHEAD OF
APPROACHING FRONT MAY LEAD TO INCREASED TDS AND HIGHER CAPE VALUES
ACROSS OUR EASTERN CWA. GFS AND NAM BOTH SHOWING VERY DIFFERENT
PICTURE REGARDING MOISTURE/CAPE PROFILES WITH NAM SHOWING BETTER
MOISTURE RETURN AND HIGHER CAPE BY 00Z. EFFECTIVE SHEER VALUES
35KT OR HIGHER WILL BE POSSIBLE...SO IF THE MORE AGGRESSIVE
GUIDANCE WAS TO VERIFY WE COULD SEE A MORE ORGANIZED SEVERE THREAT
ROUGHLY ALONG/EAST OF HIGHWAY 83. REGARDLESS OF SEVERE
THREAT...GFS/NAM BOTH SHOW THE BEST PRECIP SIGNAL IN OUR
EAST/SOUTHEAST ALONG PRE FRONTAL TROUGH...AND I RAISED POPS
ACCORDINGLY.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 225 PM MDT WED AUG 26 2015
A RIDGE WILL MOVE INTO THE ROCKIES THROUGH FRIDAY NIGHT AND THEN
START MOVING INTO THE PLAINS SATURDAY. A SURFACE TROUGH WILL MOVE
EAST ACROSS NORTHWEST KANSAS THURSDAY NIGHT FOLLOWED BY HIGH
PRESSURE WHICH SHOULD LINGER OVER THE PLAINS THROUGH SATURDAY.
A SHORTWAVE MOVING OVER THE TOP OF THE RIDGE WILL BE EXITING THE FA
THURSDAY EVENING. PLAN TO CONTINUE CHANCE/SLIGHT CHANCE POPS FOR THE
EVENING. DYNAMICS SHOULD BE EXITING THE FA AROUND 06Z FRIDAY.
SUBSIDENCE BUILDS INTO THE FA FRIDAY AND CONTINUES THROUGH SATURDAY.
POPS WILL BE NIL FOR THOSE PERIODS.
MIN TEMPERATURES SHOULD RANGE FROM THE UPPER 50S IN EASTERN COLORADO
TO THE LOWER 60S ELSEWHERE. MAX TEMPERATURES SHOULD REACH THE MID
AND UPPER 80S.
IN THE EXTENDED...(SATURDAY NIGHT THROUGH WEDNESDAY)...
THE UPPER RIDGE WILL REMAIN OVER THE PLAINS THROUGH SUNDAY AND THEN
MOVE EAST OF THE PLAINS MONDAY. THE FORECAST WILL REMAIN DRY
THROUGH MONDAY DUE TO THE LACK OF SUFFICIENT MOISTURE AND FORCING.
HOWEVER BY MONDAY EVENING MONSOONAL MOISTURE WILL BEGIN TO IMPACT
THE AREA WITH A SLIGHT CHANCE OF THUNDERSTORMS EACH AFTERNOON AND
EVENING THROUGH WEDNESDAY.
MIN TEMPERATURES SHOULD COOL TO THE LOWER AND MID 60S. MAX
TEMPERATURES SHOULD REACH THE LOWER 90S EACH DAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1150 AM MDT WED AUG 26 2015
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD AT BOTH KGLD
AND KMCK TERMINALS. GUSTY WINDS SHOULD DEVELOP AT BOTH TERMINALS
THIS AFTERNOON WITH INCREASED MIXING. AS WINDS DECREASE THIS
EVENING A DEVELOPING LOW LEVEL JET WILL LEAD TO LOW LEVEL WIND
SHEER 35-40 KT AT BOTH TERMINALS (FIRST AT KGLD AND THEN AT KMCK).
AN APPROACHING UPPER LEVEL SYSTEM MAY BRING SHOWER OR
THUNDERSTORMS TO EITHER TERMINAL BY MIDDAY THURSDAY...HOWEVER
CONFIDENCE IS TOO LOW IN COVERAGE TO INCLUDE MENTION IN TAFS
DURING THIS UPDATE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...024
SHORT TERM...DR
LONG TERM...FS
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
226 PM MDT WED AUG 26 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 110 PM MDT WED AUG 26 2015
WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS RIDGE IN PLACE ACROSS
THE PLAINS WITH 596 DM CENTER AXIS EXTENDING NORTH OVER OUR CWA.
SHORTWAVE TROUGH IS CURRENTLY ROTATING AROUND WESTERN EDGE OF RIDGE
WITH MOISTURE PLUME EXTENDING ACROSS THE CENTRAL ROCKIES AHEAD OF
THIS FEATURE. AT THE SURFACE LO PRESSURE EXTENDS FROM EASTERN
MONTANA ACROSS EASTERN COLORADO AND OVER OUR CWA. A WEAK
STATIONARY FRONT IS CURRENTLY IN PLACE FROM SW NEBRASKA AND ACROSS
CENTRAL KANSAS (NEAR HLC).
THIS AFTERNOON-TONIGHT...VERY DRY AIR MASS...STRONG CAP...AND
LIMITED LARGE SCALE FORCING WILL CONTINUE TO LIMIT CONVECTIVE
POTENTIAL. CAP MAY BEGIN TO WEAKEN ALONG STALLED FRONT IN OUR
EASTERN CWA LATER THIS AFTERNOON...HOWEVER AT THIS POINT
CONFIDENCE IS TOO LOW TO INCLUDE A MENTION OF
SHOWERS/THUNDERSTORMS. AS WAS EXPECTED HOT TEMPERATURES AND
FAVORABLE MIXING HAVE RESULTED IN VERY LOW RH VALUES THIS
AFTERNOON ACROSS THE WESTERN HALF OF OF OUR FORECAST AREA...WITH
SOME LOCATIONS GUSTING TO NEAR RFW CRITERIA. WITH FUELS STILL NOT
CONSIDERED FAVORABLE FOR RAPID FIRE SPREAD I HAVE HELD BACK ON RFW
ISSUANCE.
THURSDAY...UPPER LEVEL TROUGH WILL ROTATE AROUND THE NORTH SIDE OF
THE RIDGE AND DEEPEN AS IT TRACKS ACROSS THE NORTHERN PLAINS.
LARGE SCALE FORCING WILL OVERSPREAD OUR CWA ON THE SOUTHERN EXTENT
OF THIS FEATURE...WITH DRY AIR MASS INITIALLY LIMITING CONVECTIVE
COVERAGE UNTIL LATER THURSDAY AFTERNOON. RETURN FLOW AHEAD OF
APPROACHING FRONT MAY LEAD TO INCREASED TDS AND HIGHER CAPE VALUES
ACROSS OUR EASTERN CWA. GFS AND NAM BOTH SHOWING VERY DIFFERENT
PICTURE REGARDING MOISTURE/CAPE PROFILES WITH NAM SHOWING BETTER
MOISTURE RETURN AND HIGHER CAPE BY 00Z. EFFECTIVE SHEER VALUES
35KT OR HIGHER WILL BE POSSIBLE...SO IF THE MORE AGGRESSIVE
GUIDANCE WAS TO VERIFY WE COULD SEE A MORE ORGANIZED SEVERE THREAT
ROUGHLY ALONG/EAST OF HIGHWAY 83. REGARDLESS OF SEVERE
THREAT...GFS/NAM BOTH SHOW THE BEST PRECIP SIGNAL IN OUR
EAST/SOUTHEAST ALONG PRE FRONTAL TROUGH...AND I RAISED POPS
ACCORDINGLY.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 225 PM MDT WED AUG 26 2015
A RIDGE WILL MOVE INTO THE ROCKIES THROUGH FRIDAY NIGHT AND THEN
START MOVING INTO THE PLAINS SATURDAY. A SURFACE TROUGH WILL MOVE
EAST ACROSS NORTHWEST KANSAS THURSDAY NIGHT FOLLOWED BY HIGH
PRESSURE WHICH SHOULD LINGER OVER THE PLAINS THROUGH SATURDAY.
A SHORTWAVE MOVING OVER THE TOP OF THE RIDGE WILL BE EXITING THE FA
THURSDAY EVENING. PLAN TO CONTINUE CHANCE/SLIGHT CHANCE POPS FOR THE
EVENING. DYNAMICS SHOULD BE EXITING THE FA AROUND 06Z FRIDAY.
SUBSIDENCE BUILDS INTO THE FA FRIDAY AND CONTINUES THROUGH SATURDAY.
POPS WILL BE NIL FOR THOSE PERIODS.
MIN TEMPERATURES SHOULD RANGE FROM THE UPPER 50S IN EASTERN COLORADO
TO THE LOWER 60S ELSEWHERE. MAX TEMPERATURES SHOULD REACH THE MID
AND UPPER 80S.
IN THE EXTENDED...(SATURDAY NIGHT THROUGH WEDNESDAY)...
THE UPPER RIDGE WILL REMAIN OVER THE PLAINS THROUGH SUNDAY AND THEN
MOVE EAST OF THE PLAINS MONDAY. THE FORECAST WILL REMAIN DRY
THROUGH MONDAY DUE TO THE LACK OF SUFFICIENT MOISTURE AND FORCING.
HOWEVER BY MONDAY EVENING MONSOONAL MOISTURE WILL BEGIN TO IMPACT
THE AREA WITH A SLIGHT CHANCE OF THUNDERSTORMS EACH AFTERNOON AND
EVENING THROUGH WEDNESDAY.
MIN TEMPERATURES SHOULD COOL TO THE LOWER AND MID 60S. MAX
TEMPERATURES SHOULD REACH THE LOWER 90S EACH DAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1150 AM MDT WED AUG 26 2015
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD AT BOTH KGLD
AND KMCK TERMINALS. GUSTY WINDS SHOULD DEVELOP AT BOTH TERMINALS
THIS AFTERNOON WITH INCREASED MIXING. AS WINDS DECREASE THIS
EVENING A DEVELOPING LOW LEVEL JET WILL LEAD TO LOW LEVEL WIND
SHEER 35-40 KT AT BOTH TERMINALS (FIRST AT KGLD AND THEN AT KMCK).
AN APPROACHING UPPER LEVEL SYSTEM MAY BRING SHOWER OR
THUNDERSTORMS TO EITHER TERMINAL BY MIDDAY THURSDAY...HOWEVER
CONFIDENCE IS TOO LOW IN COVERAGE TO INCLUDE MENTION IN TAFS
DURING THIS UPDATE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...FS
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
111 PM MDT WED AUG 26 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 110 PM MDT WED AUG 26 2015
WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS RIDGE IN PLACE ACROSS
THE PLAINS WITH 596 DM CENTER AXIS EXTENDING NORTH OVER OUR CWA.
SHORTWAVE TROUGH IS CURRENTLY ROTATING AROUND WESTERN EDGE OF RIDGE
WITH MOISTURE PLUME EXTENDING ACROSS THE CENTRAL ROCKIES AHEAD OF
THIS FEATURE. AT THE SURFACE LO PRESSURE EXTENDS FROM EASTERN
MONTANA ACROSS EASTERN COLORADO AND OVER OUR CWA. A WEAK
STATIONARY FRONT IS CURRENTLY IN PLACE FROM SW NEBRASKA AND ACROSS
CENTRAL KANSAS (NEAR HLC).
THIS AFTERNOON-TONIGHT...VERY DRY AIR MASS...STRONG CAP...AND
LIMITED LARGE SCALE FORCING WILL CONTINUE TO LIMIT CONVECTIVE
POTENTIAL. CAP MAY BEGIN TO WEAKEN ALONG STALLED FRONT IN OUR
EASTERN CWA LATER THIS AFTERNOON...HOWEVER AT THIS POINT
CONFIDENCE IS TOO LOW TO INCLUDE A MENTION OF
SHOWERS/THUNDERSTORMS. AS WAS EXPECTED HOT TEMPERATURES AND
FAVORABLE MIXING HAVE RESULTED IN VERY LOW RH VALUES THIS
AFTERNOON ACROSS THE WESTERN HALF OF OF OUR FORECAST AREA...WITH
SOME LOCATIONS GUSTING TO NEAR RFW CRITERIA. WITH FUELS STILL NOT
CONSIDERED FAVORABLE FOR RAPID FIRE SPREAD I HAVE HELD BACK ON RFW
ISSUANCE.
THURSDAY...UPPER LEVEL TROUGH WILL ROTATE AROUND THE NORTH SIDE OF
THE RIDGE AND DEEPEN AS IT TRACKS ACROSS THE NORTHERN PLAINS.
LARGE SCALE FORCING WILL OVERSPREAD OUR CWA ON THE SOUTHERN EXTENT
OF THIS FEATURE...WITH DRY AIR MASS INITIALLY LIMITING CONVECTIVE
COVERAGE UNTIL LATER THURSDAY AFTERNOON. RETURN FLOW AHEAD OF
APPROACHING FRONT MAY LEAD TO INCREASED TDS AND HIGHER CAPE VALUES
ACROSS OUR EASTERN CWA. GFS AND NAM BOTH SHOWING VERY DIFFERENT
PICTURE REGARDING MOISTURE/CAPE PROFILES WITH NAM SHOWING BETTER
MOISTURE RETURN AND HIGHER CAPE BY 00Z. EFFECTIVE SHEER VALUES
35KT OR HIGHER WILL BE POSSIBLE...SO IF THE MORE AGGRESSIVE
GUIDANCE WAS TO VERIFY WE COULD SEE A MORE ORGANIZED SEVERE THREAT
ROUGHLY ALONG/EAST OF HIGHWAY 83. REGARDLESS OF SEVERE
THREAT...GFS/NAM BOTH SHOW THE BEST PRECIP SIGNAL IN OUR
EAST/SOUTHEAST ALONG PRE FRONTAL TROUGH...AND I RAISED POPS
ACCORDINGLY.
.LONG TERM...(SATURDAY THROUGH MONDAY)
ISSUED AT 154 AM MDT WED AUG 26 2015
H5 RIDGE BUILDS OVER THE SOUTHWEST ON SATURDAY AND BEGINS MOVING
EASTWARD. MID TO UPPER LEVEL FLOW BECOMES WESTERLY AND EVENTUALLY
SOUTHWESTERLY ON SUNDAY AND MONDAY AS THE RIDGE MOVES OVER THE
CENTRAL GULF COAST AND MID MISSISSIPPI VALLEY REGION. GOOD AGREEMENT
BETWEEN THE GFS AND ECMWF ABOUT THE OVERALL PATTERN ARE LEADING TO
ABOVE AVERAGE CONFIDENCE WITH REGARDS TO THE MOVEMENT OF THE RIDGE.
MOST OF THE CWA WILL REMAIN DRY ON MONDAY AND TUESDAY WITH THE
EXCEPTION OF EASTERN COLORADO DUE TO THE ADVECTION OF MONSOONAL
MOISTURE ALONG THE WESTERN SIDE OF THE RIDGE WHERE SLIGHT RAIN
CHANCES ARE POSSIBLE MONDAY EVENING AND INTO TUESDAY. ON TUESDAY
THERE WILL BE ENOUGH MARGINAL INSTABILITY ALONG A WEAK THETA E
BOUNDARY FOR ISOLATED THUNDERSTORM DEVELOPMENT IN THE WESTERN AND
NORTHWESTERN PORTIONS OF THE CWA ONCE MORE DURING THE AFTERNOON AND
EARLY EVENING. THIS BOUNDARY WILL REMAIN IN PLACE FOR THE MOST PART
THROUGHOUT THE FORECAST PERIOD AND LEAD TO SLIGHT RAIN AND
THUNDERSTORM CHANCES ONCE MORE ON WEDNESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1150 AM MDT WED AUG 26 2015
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD AT BOTH KGLD
AND KMCK TERMINALS. GUSTY WINDS SHOULD DEVELOP AT BOTH TERMINALS
THIS AFTERNOON WITH INCREASED MIXING. AS WINDS DECREASE THIS
EVENING A DEVELOPING LOW LEVEL JET WILL LEAD TO LOW LEVEL WIND
SHEER 35-40 KT AT BOTH TERMINALS (FIRST AT KGLD AND THEN AT KMCK).
AN APPROACHING UPPER LEVEL SYSTEM MAY BRING SHOWER OR
THUNDERSTORMS TO EITHER TERMINAL BY MIDDAY THURSDAY...HOWEVER
CONFIDENCE IS TOO LOW IN COVERAGE TO INCLUDE MENTION IN TAFS
DURING THIS UPDATE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...TL
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
156 AM MDT WED AUG 26 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 201 PM MDT TUE AUG 25 2015
EARLY AFTERNOON WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS RIDGE
IN PLACE ACROSS CENTRAL ROCKIES. A PLUME OF MONSOONAL MOISTURE IS
ROTATING FROM THE FOUR CORNERS REGION ROTATING INTO THE CENTRAL
ROCKIES. AT THE SURFACE LEE TROUGH IS IN PLACE ACROSS EASTERN
COLORADO WITH MAIN AXIS EXTENDING ACROSS SE COLORADO INTO SW KANSAS.
THIS AFTERNOON-EVENING...CONVECTIVE INITIATION WILL MAINLY BE ALONG
TROUGH AXIS AND ALONG HIGHER TERRAIN IN COLORADO (WEST OF OUR CWA.
CURRENTLY VERY HIGH CINH IS PREVENTING LOCAL INITIATION...HOWEVER CAP
SHOULD WEAKEN ACROSS WESTERN PARTS OF THE CWA WHERE ISOLATED
THUNDERSTORMS WILL BE POSSIBLE. THE AREAS WHERE CAP IS MOST LIKELY
TO BREAK ALSO CORRELATE WITH LOWEST CAPE/DRIEST AIR MASS...SO
COVERAGE IS LIMITED. BEYOND A VERY SMALL THREAT FOR DRY MICROBURST
POTENTIAL...CONFIDENCE IN ANY SEVERE THREAT IS LOW.
WEDNESDAY...THERE IS A STRONGER PRECIP SIGNAL THAN TODAY FROM SOME
GUIDANCE...HOWEVER SOUNDING ACTUALLY SHOW AN EVEN DRIER AIR MASS AND
STRONGER CAP THAN TODAY. VERY HOT AIR MASS WILL SUPPORT HIGHS
APPROACHING 100F OVER PARTS OF THE CWA...AND DRY ADIABATIC MIXING
MAY SUPPORT RH VALUES AND WINDS NEAR RED FLAG THRESHOLDS. WILL NEED
TO MONITOR...PARTICULARLY IN THE WESTERN PART OF THE CWA.
.LONG TERM...(SATURDAY THROUGH MONDAY)
ISSUED AT 154 AM MDT WED AUG 26 2015
H5 RIDGE BUILDS OVER THE SOUTHWEST ON SATURDAY AND BEGINS MOVING
EASTWARD. MID TO UPPER LEVEL FLOW BECOMES WESTERLY AND EVENTUALLY
SOUTHWESTERLY ON SUNDAY AND MONDAY AS THE RIDGE MOVES OVER THE
CENTRAL GULF COAST AND MID MISSISSIPPI VALLEY REGION. GOOD AGREEMENT
BETWEEN THE GFS AND ECMWF ABOUT THE OVERALL PATTERN ARE LEADING TO
ABOVE AVERAGE CONFIDENCE WITH REGARDS TO THE MOVEMENT OF THE RIDGE.
MOST OF THE CWA WILL REMAIN DRY ON MONDAY AND TUESDAY WITH THE
EXCEPTION OF EASTERN COLORADO DUE TO THE ADVECTION OF MONSOONAL
MOISTURE ALONG THE WESTERN SIDE OF THE RIDGE WHERE SLIGHT RAIN
CHANCES ARE POSSIBLE MONDAY EVENING AND INTO TUESDAY. ON TUESDAY
THERE WILL BE ENOUGH MARGINAL INSTABILITY ALONG A WEAK THETA E
BOUNDARY FOR ISOLATED THUNDERSTORM DEVELOPMENT IN THE WESTERN AND
NORTHWESTERN PORTIONS OF THE CWA ONCE MORE DURING THE AFTERNOON AND
EARLY EVENING. THIS BOUNDARY WILL REMAIN IN PLACE FOR THE MOST PART
THROUGHOUT THE FORECAST PERIOD AND LEAD TO SLIGHT RAIN AND
THUNDERSTORM CHANCES ONCE MORE ON WEDNESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1124 PM MDT TUE AUG 25 2015
PATCHY FOG WILL BE POSSIBLE AT EITHER KGLD OR KMCK AROUND SUNRISE
AS TEMPERATURES COOL TO THE DEW POINT. HOWEVER ANY FOG THAT
DEVELOPS WILL QUICKLY SCOUR OUT WITH BREEZY SOUTHWESTERLY WINDS BY
MID MORNING. OTHERWISE VFR EXPECTED WITH UPPER RIDGE REMAINING
OVER THE HIGH PLAINS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...TL
AVIATION...024
AREA FORECAST DISCUSSION
NWS JACKSON KY
150 PM EDT WED AUG 26 2015
.UPDATE...
ISSUED AT 150 PM EDT WED AUG 26 2015
CLOUD DEVELOPMENT HAS BEEN MORE EXTENSIVE THAN YESTERDAY AND
GREATER THAN EARLIER ANTICIPATED. HAVE UPDATED NDFD AND ASSOCIATED
PRODUCTS TO ACCOUNT FOR MORE CLOUD AND SLIGHTLY LOWER AFTERNOON
TEMPERATURES.
UPDATE ISSUED AT 1032 AM EDT WED AUG 26 2015
CLOUD DECK HAS BEEN ADVECTING INTO THE NORTHERN PART OF THE
FORECAST AREA...BUT ALSO SHOWING SOME SIGNS OF DIMINISHMENT AS IT
MOVES SOUTHEAST ACROSS OUR AREA. EXPECT THIS BASIC TREND TO
CONTINUE...ALONG WITH DEVELOPMENT OF SOME CU/SC JUST SOUTH OF
THE MAIN CLOUD DECK DURING THE AFTERNOON. HAVE INCREASED CLOUD
COVER IN THE SKY COVER GRIDS TO BETTER REFLECT CURRENT CONDITIONS
AND EXPECTED TRENDS. HAVE ALSO MADE SOME ADJUSTMENTS TO
TEMPERATURE AND DEWPOINT GRIDS. NDFD AND ASSOCIATED PRODUCTS HAVE
BEEN UPDATED.
UPDATE ISSUED AT 745 AM EDT WED AUG 26 2015
DID A QUICK UPDATE TO TOUCH UP THE SKY COVER AND WX GRIDS FOR THE
FOG. DID ALSO TWEAK THE T AND TD GRIDS PER THE LATEST OBS AND
TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 350 AM EDT WED AUG 26 2015
06Z SFC ANALYSIS SHOWS HIGH PRESSURE THROUGH KENTUCKY STRETCHED
BACK INTO THE HIGH PLAINS. THIS PLEASANT AIR MASS HAS ALLOWED FOR
ANOTHER SEASONABLY COOL NIGHT WHERE A SMALL RIDGE TO VALLEY
TEMPERATURE SPLIT HAS SET UP. THE RADIATIONAL COOLING...EXPECTED
TO GET MUCH OF THE AREA DOWN TO NEAR RECORD LOWS THIS NIGHT...HAS
BEEN DISRUPTED BY A PESKY LAYER OF CLOUDS AROUND 5K FEET PARKED
OVER MUCH OF EAST KENTUCKY. THIS CLOUD PATCH IS SLOWLY ERODING
FROM THE SOUTHEAST AND NORTHWEST BUT WILL STILL PROVIDE A
BLANKETING EFFECT FOR TEMPERATURES ACROSS THE CENTRAL PARTS OF THE
CWA INTO THE PRE-DAWN HOURS. THIS DISRUPTION MAY ALSO HINDER THE
FORMATION OF FOG FOR MUCH OF THE AREA...AS WELL...THOUGH STILL
EXPECT SOME ALONG THE DEEPER RIVER VALLEYS...LOCALLY DENSE FOR A
BRIEF TIME. AS IT STANDS...TEMPERATURES VARY FROM THE LOW 60S ON
THE RIDGES TO A FEW POCKETS OF LOWER 50S IN THE SHELTERED VALLEYS
BENEATH CLEAR SKIES. DEWPOINTS ARE GENERALLY IN THE LOW TO MID 50S
ACROSS THE AREA WITH LIGHT WINDS AND ONLY A FEW HINTS OF FOG
STARTING TO FORM IN THE OBS AND WEB CAMS.
THE MODELS ARE IN QUITE GOOD AGREEMENT ALOFT THROUGH THE SHORT
TERM FOR THE OHIO VALLEY IN THE WAKE OF THE DEPARTING TROUGH TO
THE NORTH. LOW HEIGHTS...WEAK RIPPLES...AND BROAD NORTHWEST FLOW
WILL BE THE RULE AT THE MID LEVELS ACROSS THE AREA THROUGH THE
DAY THURSDAY. THE CLOSED LOW WILL REMAIN CLOSE BY TODAY...
THOUGH...WITH SOME OF ITS CORE ENERGY BRUSHING PAST JUST TO THE
NORTH OF THE OHIO RIVER INTO THURSDAY MORNING. GIVEN THE MODEL
AGREEMENT HAVE FOLLOWED A GENERAL BLEND WITH A LEAN TOWARD THE
HIGHER RESOLUTION HRRR AND NAM12 FOR DETAILS.
EAST KENTUCKY WILL ENJOY A CONTINUATION OF OUR CURRENT TASTE OF
THE BEST FALL WEATHER HAS TO OFFER. PLEASANT AFTERNOON HUMIDITY
LEVELS...PARTLY TO MOSTLY SUNNY SKIES...AND TEMPERATURES TOPPING
OUT IN THE MID 70S ARE AGAIN ON THE DOCKET FOR TODAY AND THURSDAY.
THE ONLY DRAW BACK MAY BE THE PREVALENCE OF MID RANGE CLOUDS
SLIPPING SOUTH INTO OUR AREA FROM BENEATH THE UPPER LOW. TONIGHT
WILL FEATURE ANOTHER RELATIVELY COOL ONE WITH LESS CLOUDS
ANTICIPATED TO SLOW THE TEMPERATURE/S DESCENT. AS SUCH...RIDGE TO
VALLEY TEMPERATURE DIFFERENCES WILL PLAY OUT THROUGH THE NIGHT
ALONG WITH THE FORMATION OF RIVER VALLEY FOG TOWARDS DAWN
THURSDAY.
ONCE AGAIN USED THE SHORTBLEND AS A STARTING POINT FOR THE
T/TD/WIND GRIDS THROUGH THE EVENING BEFORE INITIATING WITH THE
SUPERBLEND THROUGH THE DAY THURSDAY. DID MAKE SOME SIGNIFICANT
ADJUSTMENT TO LOWS TONIGHT FOR RIDGE AND VALLEY TERRAIN EFFECTS.
AS FOR POPS...KEPT THEM EITHER ZERO OR IN THE LOW SINGLE DIGITS
THROUGH THE PERIOD...IN LINE WITH ALL MOS GUIDANCE.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 340 AM EDT WED AUG 26 2015
AT UPPER LEVELS...A STRONG MID LEVEL RIDGE DEVELOPS OVER THE WESTERN
CONUS WITH A RIDGE AXIS EXTENDING NEWD INTO THE UPPER MIDWEST.
EMBEDDED WITHIN THIS FLOW...A SHORTWAVE TROUGH DEVELOPS AND
TRAVERSES THE RIDGE TOWARDS THE MID MS VALLEY REGION BY SATURDAY
AFTERNOON. MEANWHILE...A SFC LOW DEVELOPS IN THE GULF AND MOVES
NWD...GETTING INGESTED INTO THE SHORTWAVE TROUGH AS IT CROSSES
THROUGH THE OHIO VALLEY...ULTIMATELY STRENGTHENING THE TROUGH. THERE
ARE MODEL DIFFERENCES WITH HOW THIS SITUATION EVOLVES...WITH THE GFS
BEING THE MORE AGGRESSIVE OF THE TWO MODELS.
IN TERMS OF SENSIBLE WEATHER...FRIDAY WILL BE ANOTHER BEAUTIFUL AND
DRY DAY BEFORE MOISTURE AND HUMIDITY RETURNS ON SATURDAY.
TEMPERATURES WILL BEGIN JUST BELOW NORMAL ON FRIDAY BUT THEN
GRADUALLY WARM AND RETURN BACK TO THE MID 80S BY MONDAY. THERE WILL
BE CHANCES FOR AFTERNOON SHOWERS AND A FEW THUNDERSTORMS SATURDAY
THROUGH WEDNESDAY...WITH THE BEST CHANCES ON SUNDAY AFTERNOON WITH
THE PASSAGE OF THE UPPER LEVEL SHORTWAVE. THOUGH ONE THING TO NOTE
IS THE LACK OF MOISTURE IN THE MODEL SOUNDINGS THROUGH THE EXTENDED
PERIOD. EVEN ON SUNDAY...THE UPPER LEVELS ARE SATURATED BUT THE LOW
LEVELS REMAIN FAIRLY DRY. THEREFORE HAVE MAINTAINED MAINLY SLIGHT
CHANCE POPS THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 117 PM EDT WED AUG 26 2015
SURFACE HIGH PRESSURE WILL CONTINUE TO CONTROL OUR WEATHER WITH
VFR CONDITIONS PREVAILING THROUGH THE NEXT 36 HOURS. AN EXTENSIVE
BROKEN TO OVERCAST CLOUD DECK AROUND 5K FEET WILL BE SLOW TO
DISSIPATE TONIGHT...BUT CLOUDS SHOULD EVENTUALLY SCATTER OUT. ANY
FOG FORMATION TONIGHT WILL DEPEND ON HOW LONG THE CLOUDS
LINGER...WITH FOG FORMATION LESS LIKELY THE LONGER THE CLOUDS
LAST. AT THIS POINT WILL INCLUDE A COUPLE OF HOURS OF MVFR
VISIBILITY AT SME AROUND DAWN...BUT WILL KEEP ALL OTHER TAF SITES
AT VFR.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...GREIF
LONG TERM...JVM
AVIATION...SBH
AREA FORECAST DISCUSSION
NWS JACKSON KY
117 PM EDT WED AUG 26 2015
.UPDATE...
ISSUED AT 1032 AM EDT WED AUG 26 2015
CLOUD DECK HAS BEEN ADVECTING INTO THE NORTHERN PART OF THE
FORECAST AREA...BUT ALSO SHOWING SOME SIGNS OF DIMINISHMENT AS IT
MOVES SOUTHEAST ACROSS OUR AREA. EXPECT THIS BASIC TREND TO
CONTINUE...ALONG WITH DEVELOPMENT OF SOME CU/SC JUST SOUTH OF
THE MAIN CLOUD DECK DURING THE AFTERNOON. HAVE INCREASED CLOUD
COVER IN THE SKY COVER GRIDS TO BETTER REFLECT CURRENT CONDITIONS
AND EXPECTED TRENDS. HAVE ALSO MADE SOME ADJUSTMENTS TO
TEMPERATURE AND DEWPOINT GRIDS. NDFD AND ASSOCIATED PRODUCTS HAVE
BEEN UPDATED.
UPDATE ISSUED AT 745 AM EDT WED AUG 26 2015
DID A QUICK UPDATE TO TOUCH UP THE SKY COVER AND WX GRIDS FOR THE
FOG. DID ALSO TWEAK THE T AND TD GRIDS PER THE LATEST OBS AND
TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 350 AM EDT WED AUG 26 2015
06Z SFC ANALYSIS SHOWS HIGH PRESSURE THROUGH KENTUCKY STRETCHED
BACK INTO THE HIGH PLAINS. THIS PLEASANT AIR MASS HAS ALLOWED FOR
ANOTHER SEASONABLY COOL NIGHT WHERE A SMALL RIDGE TO VALLEY
TEMPERATURE SPLIT HAS SET UP. THE RADIATIONAL COOLING...EXPECTED
TO GET MUCH OF THE AREA DOWN TO NEAR RECORD LOWS THIS NIGHT...HAS
BEEN DISRUPTED BY A PESKY LAYER OF CLOUDS AROUND 5K FEET PARKED
OVER MUCH OF EAST KENTUCKY. THIS CLOUD PATCH IS SLOWLY ERODING
FROM THE SOUTHEAST AND NORTHWEST BUT WILL STILL PROVIDE A
BLANKETING EFFECT FOR TEMPERATURES ACROSS THE CENTRAL PARTS OF THE
CWA INTO THE PRE-DAWN HOURS. THIS DISRUPTION MAY ALSO HINDER THE
FORMATION OF FOG FOR MUCH OF THE AREA...AS WELL...THOUGH STILL
EXPECT SOME ALONG THE DEEPER RIVER VALLEYS...LOCALLY DENSE FOR A
BRIEF TIME. AS IT STANDS...TEMPERATURES VARY FROM THE LOW 60S ON
THE RIDGES TO A FEW POCKETS OF LOWER 50S IN THE SHELTERED VALLEYS
BENEATH CLEAR SKIES. DEWPOINTS ARE GENERALLY IN THE LOW TO MID 50S
ACROSS THE AREA WITH LIGHT WINDS AND ONLY A FEW HINTS OF FOG
STARTING TO FORM IN THE OBS AND WEB CAMS.
THE MODELS ARE IN QUITE GOOD AGREEMENT ALOFT THROUGH THE SHORT
TERM FOR THE OHIO VALLEY IN THE WAKE OF THE DEPARTING TROUGH TO
THE NORTH. LOW HEIGHTS...WEAK RIPPLES...AND BROAD NORTHWEST FLOW
WILL BE THE RULE AT THE MID LEVELS ACROSS THE AREA THROUGH THE
DAY THURSDAY. THE CLOSED LOW WILL REMAIN CLOSE BY TODAY...
THOUGH...WITH SOME OF ITS CORE ENERGY BRUSHING PAST JUST TO THE
NORTH OF THE OHIO RIVER INTO THURSDAY MORNING. GIVEN THE MODEL
AGREEMENT HAVE FOLLOWED A GENERAL BLEND WITH A LEAN TOWARD THE
HIGHER RESOLUTION HRRR AND NAM12 FOR DETAILS.
EAST KENTUCKY WILL ENJOY A CONTINUATION OF OUR CURRENT TASTE OF
THE BEST FALL WEATHER HAS TO OFFER. PLEASANT AFTERNOON HUMIDITY
LEVELS...PARTLY TO MOSTLY SUNNY SKIES...AND TEMPERATURES TOPPING
OUT IN THE MID 70S ARE AGAIN ON THE DOCKET FOR TODAY AND THURSDAY.
THE ONLY DRAW BACK MAY BE THE PREVALENCE OF MID RANGE CLOUDS
SLIPPING SOUTH INTO OUR AREA FROM BENEATH THE UPPER LOW. TONIGHT
WILL FEATURE ANOTHER RELATIVELY COOL ONE WITH LESS CLOUDS
ANTICIPATED TO SLOW THE TEMPERATURE/S DESCENT. AS SUCH...RIDGE TO
VALLEY TEMPERATURE DIFFERENCES WILL PLAY OUT THROUGH THE NIGHT
ALONG WITH THE FORMATION OF RIVER VALLEY FOG TOWARDS DAWN
THURSDAY.
ONCE AGAIN USED THE SHORTBLEND AS A STARTING POINT FOR THE
T/TD/WIND GRIDS THROUGH THE EVENING BEFORE INITIATING WITH THE
SUPERBLEND THROUGH THE DAY THURSDAY. DID MAKE SOME SIGNIFICANT
ADJUSTMENT TO LOWS TONIGHT FOR RIDGE AND VALLEY TERRAIN EFFECTS.
AS FOR POPS...KEPT THEM EITHER ZERO OR IN THE LOW SINGLE DIGITS
THROUGH THE PERIOD...IN LINE WITH ALL MOS GUIDANCE.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 340 AM EDT WED AUG 26 2015
AT UPPER LEVELS...A STRONG MID LEVEL RIDGE DEVELOPS OVER THE WESTERN
CONUS WITH A RIDGE AXIS EXTENDING NEWD INTO THE UPPER MIDWEST.
EMBEDDED WITHIN THIS FLOW...A SHORTWAVE TROUGH DEVELOPS AND
TRAVERSES THE RIDGE TOWARDS THE MID MS VALLEY REGION BY SATURDAY
AFTERNOON. MEANWHILE...A SFC LOW DEVELOPS IN THE GULF AND MOVES
NWD...GETTING INGESTED INTO THE SHORTWAVE TROUGH AS IT CROSSES
THROUGH THE OHIO VALLEY...ULTIMATELY STRENGTHENING THE TROUGH. THERE
ARE MODEL DIFFERENCES WITH HOW THIS SITUATION EVOLVES...WITH THE GFS
BEING THE MORE AGGRESSIVE OF THE TWO MODELS.
IN TERMS OF SENSIBLE WEATHER...FRIDAY WILL BE ANOTHER BEAUTIFUL AND
DRY DAY BEFORE MOISTURE AND HUMIDITY RETURNS ON SATURDAY.
TEMPERATURES WILL BEGIN JUST BELOW NORMAL ON FRIDAY BUT THEN
GRADUALLY WARM AND RETURN BACK TO THE MID 80S BY MONDAY. THERE WILL
BE CHANCES FOR AFTERNOON SHOWERS AND A FEW THUNDERSTORMS SATURDAY
THROUGH WEDNESDAY...WITH THE BEST CHANCES ON SUNDAY AFTERNOON WITH
THE PASSAGE OF THE UPPER LEVEL SHORTWAVE. THOUGH ONE THING TO NOTE
IS THE LACK OF MOISTURE IN THE MODEL SOUNDINGS THROUGH THE EXTENDED
PERIOD. EVEN ON SUNDAY...THE UPPER LEVELS ARE SATURATED BUT THE LOW
LEVELS REMAIN FAIRLY DRY. THEREFORE HAVE MAINTAINED MAINLY SLIGHT
CHANCE POPS THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 117 PM EDT WED AUG 26 2015
SURFACE HIGH PRESSURE WILL CONTINUE TO CONTROL OUR WEATHER WITH
VFR CONDITIONS PREVAILING THROUGH THE NEXT 36 HOURS. AN EXTENSIVE
BROKEN TO OVERCAST CLOUD DECK AROUND 5K FEET WILL BE SLOW TO
DISSIPATE TONIGHT...BUT CLOUDS SHOULD EVENTUALLY SCATTER OUT. ANY
FOG FORMATION TONIGHT WILL DEPEND ON HOW LONG THE CLOUDS
LINGER...WITH FOG FORMATION LESS LIKELY THE LONGER THE CLOUDS
LAST. AT THIS POINT WILL INCLUDE A COUPLE OF HOURS OF MVFR
VISIBILITY AT SME AROUND DAWN...BUT WILL KEEP ALL OTHER TAF SITES
AT VFR.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...GREIF
LONG TERM...JVM
AVIATION...SBH
AREA FORECAST DISCUSSION
NWS JACKSON KY
1032 AM EDT WED AUG 26 2015
.UPDATE...
ISSUED AT 1032 AM EDT WED AUG 26 2015
CLOUD DECK HAS BEEN ADVECTING INTO THE NORTHERN PART OF THE
FORECAST AREA...BUT ALSO SHOWING SOME SIGNS OF DIMINISHMENT AS IT
MOVES SOUTHEAST ACROSS OUR AREA. EXPECT THIS BASIC TREND TO
CONTINUE...ALONG WITH DEVELOPMENT OF SOME CU/SC JUST SOUTH OF
THE MAIN CLOUD DECK DURING THE AFTERNOON. HAVE INCREASED CLOUD
COVER IN THE SKY COVER GRIDS TO BETTER REFLECT CURRENT CONDITIONS
AND EXPECTED TRENDS. HAVE ALSO MADE SOME ADJUSTMENTS TO
TEMPERATURE AND DEWPOINT GRIDS. NDFD AND ASSOCIATED PRODUCTS HAVE
BEEN UPDATED.
UPDATE ISSUED AT 745 AM EDT WED AUG 26 2015
DID A QUICK UPDATE TO TOUCH UP THE SKY COVER AND WX GRIDS FOR THE
FOG. DID ALSO TWEAK THE T AND TD GRIDS PER THE LATEST OBS AND
TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 350 AM EDT WED AUG 26 2015
06Z SFC ANALYSIS SHOWS HIGH PRESSURE THROUGH KENTUCKY STRETCHED
BACK INTO THE HIGH PLAINS. THIS PLEASANT AIR MASS HAS ALLOWED FOR
ANOTHER SEASONABLY COOL NIGHT WHERE A SMALL RIDGE TO VALLEY
TEMPERATURE SPLIT HAS SET UP. THE RADIATIONAL COOLING...EXPECTED
TO GET MUCH OF THE AREA DOWN TO NEAR RECORD LOWS THIS NIGHT...HAS
BEEN DISRUPTED BY A PESKY LAYER OF CLOUDS AROUND 5K FEET PARKED
OVER MUCH OF EAST KENTUCKY. THIS CLOUD PATCH IS SLOWLY ERODING
FROM THE SOUTHEAST AND NORTHWEST BUT WILL STILL PROVIDE A
BLANKETING EFFECT FOR TEMPERATURES ACROSS THE CENTRAL PARTS OF THE
CWA INTO THE PRE-DAWN HOURS. THIS DISRUPTION MAY ALSO HINDER THE
FORMATION OF FOG FOR MUCH OF THE AREA...AS WELL...THOUGH STILL
EXPECT SOME ALONG THE DEEPER RIVER VALLEYS...LOCALLY DENSE FOR A
BRIEF TIME. AS IT STANDS...TEMPERATURES VARY FROM THE LOW 60S ON
THE RIDGES TO A FEW POCKETS OF LOWER 50S IN THE SHELTERED VALLEYS
BENEATH CLEAR SKIES. DEWPOINTS ARE GENERALLY IN THE LOW TO MID 50S
ACROSS THE AREA WITH LIGHT WINDS AND ONLY A FEW HINTS OF FOG
STARTING TO FORM IN THE OBS AND WEB CAMS.
THE MODELS ARE IN QUITE GOOD AGREEMENT ALOFT THROUGH THE SHORT
TERM FOR THE OHIO VALLEY IN THE WAKE OF THE DEPARTING TROUGH TO
THE NORTH. LOW HEIGHTS...WEAK RIPPLES...AND BROAD NORTHWEST FLOW
WILL BE THE RULE AT THE MID LEVELS ACROSS THE AREA THROUGH THE
DAY THURSDAY. THE CLOSED LOW WILL REMAIN CLOSE BY TODAY...
THOUGH...WITH SOME OF ITS CORE ENERGY BRUSHING PAST JUST TO THE
NORTH OF THE OHIO RIVER INTO THURSDAY MORNING. GIVEN THE MODEL
AGREEMENT HAVE FOLLOWED A GENERAL BLEND WITH A LEAN TOWARD THE
HIGHER RESOLUTION HRRR AND NAM12 FOR DETAILS.
EAST KENTUCKY WILL ENJOY A CONTINUATION OF OUR CURRENT TASTE OF
THE BEST FALL WEATHER HAS TO OFFER. PLEASANT AFTERNOON HUMIDITY
LEVELS...PARTLY TO MOSTLY SUNNY SKIES...AND TEMPERATURES TOPPING
OUT IN THE MID 70S ARE AGAIN ON THE DOCKET FOR TODAY AND THURSDAY.
THE ONLY DRAW BACK MAY BE THE PREVALENCE OF MID RANGE CLOUDS
SLIPPING SOUTH INTO OUR AREA FROM BENEATH THE UPPER LOW. TONIGHT
WILL FEATURE ANOTHER RELATIVELY COOL ONE WITH LESS CLOUDS
ANTICIPATED TO SLOW THE TEMPERATURE/S DESCENT. AS SUCH...RIDGE TO
VALLEY TEMPERATURE DIFFERENCES WILL PLAY OUT THROUGH THE NIGHT
ALONG WITH THE FORMATION OF RIVER VALLEY FOG TOWARDS DAWN
THURSDAY.
ONCE AGAIN USED THE SHORTBLEND AS A STARTING POINT FOR THE
T/TD/WIND GRIDS THROUGH THE EVENING BEFORE INITIATING WITH THE
SUPERBLEND THROUGH THE DAY THURSDAY. DID MAKE SOME SIGNIFICANT
ADJUSTMENT TO LOWS TONIGHT FOR RIDGE AND VALLEY TERRAIN EFFECTS.
AS FOR POPS...KEPT THEM EITHER ZERO OR IN THE LOW SINGLE DIGITS
THROUGH THE PERIOD...IN LINE WITH ALL MOS GUIDANCE.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 340 AM EDT WED AUG 26 2015
AT UPPER LEVELS...A STRONG MID LEVEL RIDGE DEVELOPS OVER THE WESTERN
CONUS WITH A RIDGE AXIS EXTENDING NEWD INTO THE UPPER MIDWEST.
EMBEDDED WITHIN THIS FLOW...A SHORTWAVE TROUGH DEVELOPS AND
TRAVERSES THE RIDGE TOWARDS THE MID MS VALLEY REGION BY SATURDAY
AFTERNOON. MEANWHILE...A SFC LOW DEVELOPS IN THE GULF AND MOVES
NWD...GETTING INGESTED INTO THE SHORTWAVE TROUGH AS IT CROSSES
THROUGH THE OHIO VALLEY...ULTIMATELY STRENGTHENING THE TROUGH. THERE
ARE MODEL DIFFERENCES WITH HOW THIS SITUATION EVOLVES...WITH THE GFS
BEING THE MORE AGGRESSIVE OF THE TWO MODELS.
IN TERMS OF SENSIBLE WEATHER...FRIDAY WILL BE ANOTHER BEAUTIFUL AND
DRY DAY BEFORE MOISTURE AND HUMIDITY RETURNS ON SATURDAY.
TEMPERATURES WILL BEGIN JUST BELOW NORMAL ON FRIDAY BUT THEN
GRADUALLY WARM AND RETURN BACK TO THE MID 80S BY MONDAY. THERE WILL
BE CHANCES FOR AFTERNOON SHOWERS AND A FEW THUNDERSTORMS SATURDAY
THROUGH WEDNESDAY...WITH THE BEST CHANCES ON SUNDAY AFTERNOON WITH
THE PASSAGE OF THE UPPER LEVEL SHORTWAVE. THOUGH ONE THING TO NOTE
IS THE LACK OF MOISTURE IN THE MODEL SOUNDINGS THROUGH THE EXTENDED
PERIOD. EVEN ON SUNDAY...THE UPPER LEVELS ARE SATURATED BUT THE LOW
LEVELS REMAIN FAIRLY DRY. THEREFORE HAVE MAINTAINED MAINLY SLIGHT
CHANCE POPS THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 800 AM EDT WED AUG 26 2015
VFR CONDITIONS ARE EXPECTED OVER THE NEXT 24 TO 36 HOURS FOR MOST
OF EASTERN KENTUCKY. THE EXCEPTION WILL BE SOME RIVER VALLEY FOG
TOWARDS DAWN THURSDAY. THIS SHOULD NOT IMPACT MOST OF THE TAF
SITES...WITH THE BEST SHOT BEING KSME. FOR THIS...HAVE INCLUDED A
BRIEF PERIOD OF MVFR VIS. WINDS WILL BE LIGHT AND VARIABLE
THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...GREIF
LONG TERM...JVM
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
800 AM EDT WED AUG 26 2015
.UPDATE...
ISSUED AT 745 AM EDT WED AUG 26 2015
DID A QUICK UPDATE TO TOUCH UP THE SKY COVER AND WX GRIDS FOR THE
FOG. DID ALSO TWEAK THE T AND TD GRIDS PER THE LATEST OBS AND
TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 350 AM EDT WED AUG 26 2015
06Z SFC ANALYSIS SHOWS HIGH PRESSURE THROUGH KENTUCKY STRETCHED
BACK INTO THE HIGH PLAINS. THIS PLEASANT AIR MASS HAS ALLOWED FOR
ANOTHER SEASONABLY COOL NIGHT WHERE A SMALL RIDGE TO VALLEY
TEMPERATURE SPLIT HAS SET UP. THE RADIATIONAL COOLING...EXPECTED
TO GET MUCH OF THE AREA DOWN TO NEAR RECORD LOWS THIS NIGHT...HAS
BEEN DISRUPTED BY A PESKY LAYER OF CLOUDS AROUND 5K FEET PARKED
OVER MUCH OF EAST KENTUCKY. THIS CLOUD PATCH IS SLOWLY ERODING
FROM THE SOUTHEAST AND NORTHWEST BUT WILL STILL PROVIDE A
BLANKETING EFFECT FOR TEMPERATURES ACROSS THE CENTRAL PARTS OF THE
CWA INTO THE PRE-DAWN HOURS. THIS DISRUPTION MAY ALSO HINDER THE
FORMATION OF FOG FOR MUCH OF THE AREA...AS WELL...THOUGH STILL
EXPECT SOME ALONG THE DEEPER RIVER VALLEYS...LOCALLY DENSE FOR A
BRIEF TIME. AS IT STANDS...TEMPERATURES VARY FROM THE LOW 60S ON
THE RIDGES TO A FEW POCKETS OF LOWER 50S IN THE SHELTERED VALLEYS
BENEATH CLEAR SKIES. DEWPOINTS ARE GENERALLY IN THE LOW TO MID 50S
ACROSS THE AREA WITH LIGHT WINDS AND ONLY A FEW HINTS OF FOG
STARTING TO FORM IN THE OBS AND WEB CAMS.
THE MODELS ARE IN QUITE GOOD AGREEMENT ALOFT THROUGH THE SHORT
TERM FOR THE OHIO VALLEY IN THE WAKE OF THE DEPARTING TROUGH TO
THE NORTH. LOW HEIGHTS...WEAK RIPPLES...AND BROAD NORTHWEST FLOW
WILL BE THE RULE AT THE MID LEVELS ACROSS THE AREA THROUGH THE
DAY THURSDAY. THE CLOSED LOW WILL REMAIN CLOSE BY TODAY...
THOUGH...WITH SOME OF ITS CORE ENERGY BRUSHING PAST JUST TO THE
NORTH OF THE OHIO RIVER INTO THURSDAY MORNING. GIVEN THE MODEL
AGREEMENT HAVE FOLLOWED A GENERAL BLEND WITH A LEAN TOWARD THE
HIGHER RESOLUTION HRRR AND NAM12 FOR DETAILS.
EAST KENTUCKY WILL ENJOY A CONTINUATION OF OUR CURRENT TASTE OF
THE BEST FALL WEATHER HAS TO OFFER. PLEASANT AFTERNOON HUMIDITY
LEVELS...PARTLY TO MOSTLY SUNNY SKIES...AND TEMPERATURES TOPPING
OUT IN THE MID 70S ARE AGAIN ON THE DOCKET FOR TODAY AND THURSDAY.
THE ONLY DRAW BACK MAY BE THE PREVALENCE OF MID RANGE CLOUDS
SLIPPING SOUTH INTO OUR AREA FROM BENEATH THE UPPER LOW. TONIGHT
WILL FEATURE ANOTHER RELATIVELY COOL ONE WITH LESS CLOUDS
ANTICIPATED TO SLOW THE TEMPERATURE/S DESCENT. AS SUCH...RIDGE TO
VALLEY TEMPERATURE DIFFERENCES WILL PLAY OUT THROUGH THE NIGHT
ALONG WITH THE FORMATION OF RIVER VALLEY FOG TOWARDS DAWN
THURSDAY.
ONCE AGAIN USED THE SHORTBLEND AS A STARTING POINT FOR THE
T/TD/WIND GRIDS THROUGH THE EVENING BEFORE INITIATING WITH THE
SUPERBLEND THROUGH THE DAY THURSDAY. DID MAKE SOME SIGNIFICANT
ADJUSTMENT TO LOWS TONIGHT FOR RIDGE AND VALLEY TERRAIN EFFECTS.
AS FOR POPS...KEPT THEM EITHER ZERO OR IN THE LOW SINGLE DIGITS
THROUGH THE PERIOD...IN LINE WITH ALL MOS GUIDANCE.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 340 AM EDT WED AUG 26 2015
AT UPPER LEVELS...A STRONG MID LEVEL RIDGE DEVELOPS OVER THE WESTERN
CONUS WITH A RIDGE AXIS EXTENDING NEWD INTO THE UPPER MIDWEST.
EMBEDDED WITHIN THIS FLOW...A SHORTWAVE TROUGH DEVELOPS AND
TRAVERSES THE RIDGE TOWARDS THE MID MS VALLEY REGION BY SATURDAY
AFTERNOON. MEANWHILE...A SFC LOW DEVELOPS IN THE GULF AND MOVES
NWD...GETTING INGESTED INTO THE SHORTWAVE TROUGH AS IT CROSSES
THROUGH THE OHIO VALLEY...ULTIMATELY STRENGTHENING THE TROUGH. THERE
ARE MODEL DIFFERENCES WITH HOW THIS SITUATION EVOLVES...WITH THE GFS
BEING THE MORE AGGRESSIVE OF THE TWO MODELS.
IN TERMS OF SENSIBLE WEATHER...FRIDAY WILL BE ANOTHER BEAUTIFUL AND
DRY DAY BEFORE MOISTURE AND HUMIDITY RETURNS ON SATURDAY.
TEMPERATURES WILL BEGIN JUST BELOW NORMAL ON FRIDAY BUT THEN
GRADUALLY WARM AND RETURN BACK TO THE MID 80S BY MONDAY. THERE WILL
BE CHANCES FOR AFTERNOON SHOWERS AND A FEW THUNDERSTORMS SATURDAY
THROUGH WEDNESDAY...WITH THE BEST CHANCES ON SUNDAY AFTERNOON WITH
THE PASSAGE OF THE UPPER LEVEL SHORTWAVE. THOUGH ONE THING TO NOTE
IS THE LACK OF MOISTURE IN THE MODEL SOUNDINGS THROUGH THE EXTENDED
PERIOD. EVEN ON SUNDAY...THE UPPER LEVELS ARE SATURATED BUT THE LOW
LEVELS REMAIN FAIRLY DRY. THEREFORE HAVE MAINTAINED MAINLY SLIGHT
CHANCE POPS THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 800 AM EDT WED AUG 26 2015
VFR CONDITIONS ARE EXPECTED OVER THE NEXT 24 TO 36 HOURS FOR MOST
OF EASTERN KENTUCKY. THE EXCEPTION WILL BE SOME RIVER VALLEY FOG
TOWARDS DAWN THURSDAY. THIS SHOULD NOT IMPACT MOST OF THE TAF
SITES...WITH THE BEST SHOT BEING KSME. FOR THIS...HAVE INCLUDED A
BRIEF PERIOD OF MVFR VIS. WINDS WILL BE LIGHT AND VARIABLE
THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...GREIF
LONG TERM...JVM
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS JACKSON KY
350 AM EDT WED AUG 26 2015
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 350 AM EDT WED AUG 26 2015
06Z SFC ANALYSIS SHOWS HIGH PRESSURE THROUGH KENTUCKY STRETCHED
BACK INTO THE HIGH PLAINS. THIS PLEASANT AIR MASS HAS ALLOWED FOR
ANOTHER SEASONABLY COOL NIGHT WHERE A SMALL RIDGE TO VALLEY
TEMPERATURE SPLIT HAS SET UP. THE RADIATIONAL COOLING...EXPECTED
TO GET MUCH OF THE AREA DOWN TO NEAR RECORD LOWS THIS NIGHT...HAS
BEEN DISRUPTED BY A PESKY LAYER OF CLOUDS AROUND 5K FEET PARKED
OVER MUCH OF EAST KENTUCKY. THIS CLOUD PATCH IS SLOWLY ERODING
FROM THE SOUTHEAST AND NORTHWEST BUT WILL STILL PROVIDE A
BLANKETING EFFECT FOR TEMPERATURES ACROSS THE CENTRAL PARTS OF THE
CWA INTO THE PRE-DAWN HOURS. THIS DISRUPTION MAY ALSO HINDER THE
FORMATION OF FOG FOR MUCH OF THE AREA...AS WELL...THOUGH STILL
EXPECT SOME ALONG THE DEEPER RIVER VALLEYS...LOCALLY DENSE FOR A
BRIEF TIME. AS IT STANDS...TEMPERATURES VARY FROM THE LOW 60S ON
THE RIDGES TO A FEW POCKETS OF LOWER 50S IN THE SHELTERED VALLEYS
BENEATH CLEAR SKIES. DEWPOINTS ARE GENERALLY IN THE LOW TO MID 50S
ACROSS THE AREA WITH LIGHT WINDS AND ONLY A FEW HINTS OF FOG
STARTING TO FORM IN THE OBS AND WEB CAMS.
THE MODELS ARE IN QUITE GOOD AGREEMENT ALOFT THROUGH THE SHORT
TERM FOR THE OHIO VALLEY IN THE WAKE OF THE DEPARTING TROUGH TO
THE NORTH. LOW HEIGHTS...WEAK RIPPLES...AND BROAD NORTHWEST FLOW
WILL BE THE RULE AT THE MID LEVELS ACROSS THE AREA THROUGH THE
DAY THURSDAY. THE CLOSED LOW WILL REMAIN CLOSE BY TODAY...
THOUGH...WITH SOME OF ITS CORE ENERGY BRUSHING PAST JUST TO THE
NORTH OF THE OHIO RIVER INTO THURSDAY MORNING. GIVEN THE MODEL
AGREEMENT HAVE FOLLOWED A GENERAL BLEND WITH A LEAN TOWARD THE
HIGHER RESOLUTION HRRR AND NAM12 FOR DETAILS.
EAST KENTUCKY WILL ENJOY A CONTINUATION OF OUR CURRENT TASTE OF
THE BEST FALL WEATHER HAS TO OFFER. PLEASANT AFTERNOON HUMIDITY
LEVELS...PARTLY TO MOSTLY SUNNY SKIES...AND TEMPERATURES TOPPING
OUT IN THE MID 70S ARE AGAIN ON THE DOCKET FOR TODAY AND THURSDAY.
THE ONLY DRAW BACK MAY BE THE PREVALENCE OF MID RANGE CLOUDS
SLIPPING SOUTH INTO OUR AREA FROM BENEATH THE UPPER LOW. TONIGHT
WILL FEATURE ANOTHER RELATIVELY COOL ONE WITH LESS CLOUDS
ANTICIPATED TO SLOW THE TEMPERATURE/S DESCENT. AS SUCH...RIDGE TO
VALLEY TEMPERATURE DIFFERENCES WILL PLAY OUT THROUGH THE NIGHT
ALONG WITH THE FORMATION OF RIVER VALLEY FOG TOWARDS DAWN
THURSDAY.
ONCE AGAIN USED THE SHORTBLEND AS A STARTING POINT FOR THE
T/TD/WIND GRIDS THROUGH THE EVENING BEFORE INITIATING WITH THE
SUPERBLEND THROUGH THE DAY THURSDAY. DID MAKE SOME SIGNIFICANT
ADJUSTMENT TO LOWS TONIGHT FOR RIDGE AND VALLEY TERRAIN EFFECTS.
AS FOR POPS...KEPT THEM EITHER ZERO OR IN THE LOW SINGLE DIGITS
THROUGH THE PERIOD...IN LINE WITH ALL MOS GUIDANCE.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 340 AM EDT WED AUG 26 2015
AT UPPER LEVELS...A STRONG MID LEVEL RIDGE DEVELOPS OVER THE WESTERN
CONUS WITH A RIDGE AXIS EXTENDING NEWD INTO THE UPPER MIDWEST.
EMBEDDED WITHIN THIS FLOW...A SHORTWAVE TROUGH DEVELOPS AND
TRAVERSES THE RIDGE TOWARDS THE MID MS VALLEY REGION BY SATURDAY
AFTERNOON. MEANWHILE...A SFC LOW DEVELOPS IN THE GULF AND MOVES
NWD...GETTING INGESTED INTO THE SHORTWAVE TROUGH AS IT CROSSES
THROUGH THE OHIO VALLEY...ULTIMATELY STRENGTHENING THE TROUGH. THERE
ARE MODEL DIFFERENCES WITH HOW THIS SITUATION EVOLVES...WITH THE GFS
BEING THE MORE AGGRESSIVE OF THE TWO MODELS.
IN TERMS OF SENSIBLE WEATHER...FRIDAY WILL BE ANOTHER BEAUTIFUL AND
DRY DAY BEFORE MOISTURE AND HUMIDITY RETURNS ON SATURDAY.
TEMPERATURES WILL BEGIN JUST BELOW NORMAL ON FRIDAY BUT THEN
GRADUALLY WARM AND RETURN BACK TO THE MID 80S BY MONDAY. THERE WILL
BE CHANCES FOR AFTERNOON SHOWERS AND A FEW THUNDERSTORMS SATURDAY
THROUGH WEDNESDAY...WITH THE BEST CHANCES ON SUNDAY AFTERNOON WITH
THE PASSAGE OF THE UPPER LEVEL SHORTWAVE. THOUGH ONE THING TO NOTE
IS THE LACK OF MOISTURE IN THE MODEL SOUNDINGS THROUGH THE EXTENDED
PERIOD. EVEN ON SUNDAY...THE UPPER LEVELS ARE SATURATED BUT THE LOW
LEVELS REMAIN FAIRLY DRY. THEREFORE HAVE MAINTAINED MAINLY SLIGHT
CHANCE POPS THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 230 AM EDT WED AUG 26 2015
VFR CONDITIONS ARE EXPECTED OVER THE NEXT 24 TO 36 HOURS FOR MOST
OF EASTERN KENTUCKY. THE EXCEPTION WILL BE SOME RIVER VALLEY FOG
TOWARD DAWN. THIS SHOULD NOT IMPACT MOST OF THE TAF SITES...WITH
THE BEST SHOT BEING KSME. FOR THIS...HAVE INCLUDED A BRIEF PERIOD
OF IFR VIS AND LOW CIGS TOWARD DAWN BEFORE QUICKLY DISSIPATING.
WINDS WILL BE LIGHT AND VARIABLE THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...JVM
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS CARIBOU ME
640 PM EDT WED AUG 26 2015
.SYNOPSIS...
AN UPPER LEVEL TROUGH OF LOW PRESSURE WILL APPROACH TONIGHT AND MOVE
OVER THE REGION ON THURSDAY. THE TROUGH WILL LIFT NORTHEAST OF THE
AREA THURSDAY NIGHT. HIGH PRESSURE WILL BUILD ALONG THE MID ATLANTIC
COAST FRIDAY INTO SATURDAY.
&&
.NEAR TERM /THROUGH THURSDAY/...
615 PM UPDATE: LATEST RADAR REF SHOWS A ROUND OF CNVCTN WEAKENING
AS IT MOVES FROM WRN ME INTO E CNTRL ME. LAPS SHOWS MUCH LESS
AVBL SBCAPE OVR OUR FA COMPARED TO WFO GYX`S AREA...SO THIS TREND
MATCHES THE ENVIRONMENTAL SET-UP. SO THE ONLY OTHER CONCERN ATTM
IS WHETHER ANY ADDITIONAL HVY SHWR/TSTM ACTIVITY MOVES ACROSS
CNTRL WASHINGTON COUNTY...WHERE THERE WAS FLASH FLOODING EARLY
THIS MORN...LATER TNGT BEFORE WHAT LEFT OF THE FRONT OVR THE FA
MOVES E OF THE FA. LATEST HRRR MODEL OUTPUT SUGGESTS ADDITIONAL
CNVCTN OVR THIS PTN OF THE FA PRIOR TO 06Z...BUT OTHER SYNOPTIC
SCALE MODELS LIKE THE GFS AND ECMWF SUGGEST ADDITIONAL ACTIVITY
MAY MOVE SW TO NE INTO NB PROV JUST E OF WASHINGTON COUNTY...
SO WE WILL WAIT AND SEE.
MEANWHILE...FCST HRLY TEMPS FOR THE OVRNGT WERE UPDATED FROM OBSVD
HI TEMPS EARLIER THIS AFTN THRU OBSVD 6 PM TEMPS TO UNCHGD FCST
LOWS POSTED AT 6 AM THU. LASTLY...HI TRRN RESOLUTION TEMPS WERE
RETURNED FROM THIS AFTN THRU THU.
ORGNL DISC: SFC BNDRY HAS SLOWLY CREEPED INTO EXTRM WRN PART OF
CWA WITH NW WIND AT GREENVILLE AND SE WIND AT MILLINOCKET. THIS
BNDRY IS ALLOWING MOISTURE TO STREAM NWRD ON 30KT H8 LLJ. SHOWERS
AND ISOLD STORMS CONTINUE TO RE-DEVELOP AT THIS TIME. EXPECT THESE
WL CONTINUE OFF AND ON INTO THE EVNG HRS. BIGGEST CONCERN CONTS TO
CENTER ARND WASHINGTON CNTY. THIS AREA WAS HIT HARD THIS MRNG WITH
HVY RAIN AND FLOODING AS A RESULT OF LFQ OF H2 JET. MED RANGE
MODELS INDICATING ANOTHER JET DVLPNG LATE TONIGHT. THIS JET IS
BEING PICKED UP ON WV IMAGERY AT THIS TIME ALONG THE ERN SEABOARD.
AS THIS JET INTENSIFIES IT WL LKLY INDUCE SFC LOW DVLPMNT IN THE
GULF OF MAINE. UPR LVL SUPPORT FM JET MAX COUPLED WITH LOW-LVL
CONVERGENCE WITH SFC LOW AND PW VALUES OF 1.50+ INCHES WL LKLY LEAD
TO HVY RAINFALL AGAIN OVRNGT. WL HIGHLIGHT THREAT IN HWO AND ALLOW
LATER SHIFTS TO MAKE THE CALL ON A POSSIBLE WATCH. SFC LOPRES WL
RESULT IN SLOW MVMNT TO FRONT AND NOT CLR CWA UNTIL 12Z THUR.
ELEVATED INSTABILITY WL WANE ACRS MOST OF CWA AFT 00Z BUT WL
CONTINUE THRU ABOUT 06Z OVR WASHINGTON CNTY. THUS HV MAINTAINED
ISOLD THUNDER THRU THIS TIME.
DRY DWPTS WL FILTER INTO THE NW IN WAKE OF FROPA AS DWPTS ACRS
CANADA HV DROPPED INTO THE M50S. THUS, EXPECT THAT MINS OVRNGT IN
THE NORTH WOOD CUD DROP INTO THE M/U 50S WITH LOCALES ALONG THE
COAST IN THE L60S.
DRG THE DAY THURSDAY EXPECT UPR LVL TROF TO SWING THRU THE STATE.
THIS WL LEAD TO ANOTHER ROUND OF SHOWERS AND ISOLD THUNDER ACRS THE
CROWN OF MAINE. COLD TEMPS ALOFT WL MV THRU DRG THE AFTN AT TIME OF
MAX DIURNAL HTG.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
THE TROUGH OF LOW PRESSURE WHICH HAS BEEN BRINGING SHOWERS THE LAST
FEW DAYS WILL BE WEAKENING AND LIFTING OUT TO THE NORTHEAST THURSDAY
NIGHT AS HIGH PRESSURE BEGINS TO BUILD TOWARD THE MID ATLANTIC
REGION. THE HIGH WILL BRING MOSTLY SUNNY AND DRY WEATHER ON FRIDAY.
A WEAK FRONTAL BOUNDARY DROPPING DOWN FROM THE NORTH MAY BRING SOME
CLOUDINESS TO FAR NORTHERN AREAS LATE IN THE DAY. FRIDAY NIGHT WILL
BE CLEAR TO PARTLY CLOUDY. SATURDAY SHOULD THEN BE ANOTHER DRY DAY
AS HIGH PRESSURE MOVES OFF THE EAST COAST. SOME CLOUDS MAY INCREASE
LATE IN THE DAY AHEAD OF A WEAK TROUGH APPROACHING FROM THE WEST.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THE WEAK TROUGH MOVING ACROSS THE AREA SATURDAY NIGHT INTO SUNDAY
WILL BRING A PARTLY TO MOSTLY CLOUDY DAY WITH THE CHANCE FOR SOME
SPOTTY SHOWERS OR A THUNDERSTORM, ESPECIALLY OVER THE NORTH WHERE A
WEAK FRONTAL BOUNDARY WILL BE PUSHING IN. THE TROUGH WILL QUICKLY
MOVE AWAY SUNDAY NIGHT. HIGH PRESSURE SUPPORTED BY STRONG UPPER
LEVEL RIDGING SHOULD THEN BUILD OVER THE AREA BRINGING SUNNY DRY
WEATHER ON MONDAY. RIDGING WILL CONTINUE TO SUPPORT SUNSHINE AND DRY
WEATHER ON TUESDAY WITH TEMPS A BIT WARMER AS A WEST SOUTHWESTERLY
BREEZE CIRCULATES IN BEHIND THE HIGH. DRY WEATHER SHOULD PERSIST
INTO MID WEEK DOWNEAST WHILE A WEAK FRONTAL BOUNDARY PUSHING INTO
THE NORTH WILL BRING A CHANCE FOR SHOWERS OVER NORTHERN AREAS ON
WEDNESDAY.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
NEAR TERM: IFR CONDITIONS EXPECTED MAJORITY OF TAF VALID TIME IN
MOIST AND HUMID AIRMASS. EXPECT HEAVY SHOWERS AT MOST TERMINALS
THOUGH -TSRA IS POSSIBLE AT HUL THROUGH 20Z THIS AFTERNOON. AS
DRIER AIR WORKS IN BEHIND FRONTAL BOUNDARY TONIGHT EXPECTED
CONDITIONS TO INCREASE TO MVFR AFTER DAYBREAK.
SHORT TERM: VFR CONDITIONS ARE EXPECTED THURSDAY NIGHT THROUGH
SATURDAY AS HIGH PRESSURE BUILDS SOUTH OF THE AREA. CONDITIONS MAY
LOWER TO MVFR AT TIMES SATURDAY NIGHT INTO SUNDAY WITH CLOUDS AND
SOME SHOWERS. CONDITIONS WILL RETURN TO VFR SUNDAY NIGHT AND
REMAIN VFR ON MONDAY AS HIGH PRESSURE RETURNS.
&&
.MARINE...
NEAR TERM: VISIBILITIES WILL BE REDUCED IN AREAS OF FOG ONCE AGAIN
TONIGHT. WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY
CRITERIA. SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE TONIGHT.
SHORT TERM: WINDS AND SEAS ARE EXPECTED TO REMAIN BELOW SCA
THROUGH MID WEEK NEXT WEEK WITH HIGH PRESSURE SOUTH OF THE WATERS
EARLY THIS WEEKEND AND ANOTHER HIGH OVER THE WATERS EARLY NEXT
WEEK.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...VJN
SHORT TERM...BLOOMER
LONG TERM...BLOOMER
AVIATION...VJN/BLOOMER
MARINE...VJN/BLOOMER
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1246 AM EDT WED AUG 26 2015
.SYNOPSIS...
A COLD FRONT WILL SLOWLY APPROACH LATE TONIGHT...THEN CROSS THE
REGION LATER WEDNESDAY. HIGH PRESSURE WILL BUILD ACROSS THE REGION
LATER THURSDAY INTO FRIDAY.
&&
.NEAR TERM /THROUGH TODAY/...
UPDATE: ADJUSTED POPS BASED ON LATEST RADAR REFLECTIVITY IMAGERY.
USED HRRR POPS FOR THE OVERNIGHT HOURS WHICH SEEMED TO BE HANDLING
THINGS PRETTY WELL THIS HOUR. WILL CONTINUE TO MENTION HEAVY
DOWNPOURS IN ANY SHOWERS AND TSTMS OVERNIGHT WITH PWATS RUNNING
1.5 TO 2.0 INCHES. ONLY OTHER CHANGES WERE SOME MINOR TWEAKS TO
TEMPS/DEW POINTS.
OTHERWISE...FCST HRLY TEMPS WERE UPDATED FROM OBSVD 9 PM TEMPS...TO
FCST LOWS POSTED AT 6 AM WED WHICH WERE LOWERED SLIGHTLY OVR THE
NW GIVEN SLIGHTLY NEGATIVE TRENDS FROM THE PRIOR FCST TEMPS AT
THIS HR OVR THE NW. LASTLY...WE INCORPORATED MORE HI TRRN DAY/NGT
TEMP DIURNAL VARIATION THRU WED.
ORGNL DISC: A SLOW MOVING COLD FRONT WILL APPROACH FROM THE WEST
TONIGHT...THEN BEGIN TO CROSS THE REGION WEDNESDAY. SHOWERS AND
THUNDERSTORMS WILL OCCUR ACROSS THE REGION TONIGHT THROUGH
WEDNESDAY IN ADVANCE OF THE FRONT. WITH ABUNDANT LOW LEVEL
MOISTURE...LOCALLY HEAVY RAINS COULD OCCUR WITH ANY THUNDERSTORMS
OR HEAVIER SHOWERS EARLY TONIGHT. FOG WILL ALSO MOVE INLAND FROM
THE GULF OF MAINE TONIGHT...MOST EXTENSIVE ACROSS DOWNEAST AREAS.
OVERNIGHT LOW TEMPERATURES WILL RANGE FROM THE LOWER TO MID 60S
ACROSS THE REGION. HIGH TEMPERATURES WEDNESDAY WILL GENERALLY
RANGE FROM THE LOWER TO MID 70S ACROSS THE FORECAST AREA.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY/...
FOR WEDNESDAY NIGHT...THE COLD FRONT WILL SLOWLY EXIT THE EASTERN
PORTION OF THE FORECAST AREA LATER IN THE EVENING. SHOWERS AND
THUNDERSTORMS WILL END AS THE FRONT EXITS THE AREA. FURTHER
WEST...TOWARDS BANGOR AND GREENVILLE....SHOWERS WILL END EARLY THE
EVENING. MARGINALLY DRIER AND SLIGHTLY COOLER AIR WILL ADVECT INTO
THE REGION LATER IN THE NIGHT AND PUSH THE STRATUS CLOUDS OUT OF
THE AREA. HOWEVER...IT WILL STILL BE ANOTHER HUMID NIGHT WITH
DEWPOINTS ABOVE 60F MOST OF THE NIGHT AND COASTAL FOG WILL
PROBABLY LINGER THROUGH THE NIGHT. LOWS WILL STILL BE IN THE UPPER
50S TO NEAR 60F. A POST-FRONTAL SURFACE TROUGH ON THURSDAY
AFTERNOON WILL FINALLY BRING IN SIGNIFICANTLY LESS HUMID AIR FOR
THE FIRST TIME IN NEARLY TWO WEEKS. THIS SURFACE TROUGH WILL
COINCIDE WITH THE PASSAGE OF AN UPPER LEVEL TROUGH AND SET OFF
SHOWERS THURSDAY AFTERNOON WITH MODEST AMOUNTS OF CAPE BUT FAR
LESS PRECIPITABLE WATER. AS A RESULT...IT IS HARD TO FORESEE MUCH
MORE THAN A TENTH OF AN INCH OF RAINFALL WITH THESE SHOWERS.. AN
ISOLATED THUNDERSTORM CANNOT BE RULED OUT. HIGHS ON THURSDAY WILL
RANGE FROM THE LOWER 70S NORTH TO MID-UPPER 70S FOR BANGOR AND
DOWN EAST. THE OFFSHORE FLOW WILL ENSURE THAT THE WARMEST
TEMPERATURES ARE TOWARDS THE COAST. THE COOLER AIR WILL BE IN
PLACE THURSDAY NIGHT UNDER HIGH PRESSURE. LOWS WILL DROP TO THE
UPPER 40S IN THE ALLAGASH WHILE LOW TO MID 50S ARE ANTICIPATED
ELSEWHERE. THE HIGH REMAINS IN PLACE FOR FRIDAY. HIGHS ON FRIDAY
WILL BE IN THE LOW TO MID 70S WITH LOW HUMIDITY. AGAIN...THE
OFFSHORE FLOW WILL PRODUCE HIGHER TEMPERATURES TOWARDS THE COAST.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
A RIDGE OF HIGH PRESSURE WILL BE LOCATED ALONG THE EAST COAST FRIDAY
NIGHT AS A WEAK TROUGH IN EASTERN CANADA PUSHES A WEAKENING COLD
FRONT THROUGH OUR AREA. THIS WILL BRING A PARTLY CLOUDY NIGHT FRIDAY
NIGHT. THE FRONT WILL PUSH BACK NORTH AS A WARM FRONT ON SATURDAY AS
MOISTURE LIFTS NORTH BEHIND THE HIGH WHICH WILL BE MOVING OUT
INTO THE ATLANTIC. THE MOISTURE WILL BRING INCREASING CLOUDS
SATURDAY AND SOME SHOWERS ARE POSSIBLE OVER THE NORTH SATURDAY
AFTERNOON. A WEATHER DISTURBANCE MAY BRING SHOWERS THROUGHOUT THE
AREA SATURDAY NIGHT INTO SUNDAY. DRY WEATHER SHOULD THEN RETURN
MONDAY INTO TUESDAY AS HIGH PRESSURE BUILDS BACK INTO THE EAST
ALONG WITH SOME UPPER LEVEL RIDGING.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
NEAR TERM: VARIABLE CONDITIONS WILL OCCUR ACROSS THE REGION THIS
EVENING RANGING FROM VFR TO LIFR. IFR TO VLIFR CONDITIONS ARE THEN
EXPECTED ACROSS THE FORECAST AREA OVERNIGHT INTO EARLY WEDNESDAY.
GENERALLY EXPECT MVFR TO LIFR CONDITIONS ACROSS THE REGION LATER
WEDNESDAY MORNING THROUGH THE AFTERNOON.
SHORT TERM: EXPECT PREDOMINATELY IFR CONDITIONS WEDNESDAY NIGHT
WITH THUNDERSTORMS POSSIBLE IN THE EVENING. LIFR IS LIKELY TOWARDS
BHB AND THE COAST WEDNESDAY NIGHT IN FOG. CONDITIONS WILL BECOME
VFR THURSDAY THROUGH FRIDAY FOR ALL TERMINALS. VFR CONDITIONS ARE
EXPECTED EARLY SATURDAY. CONDITIONS MAY LOWER TO MVFR ACROSS THE
NORTH SATURDAY AFTERNOON.
&&
.MARINE...
NEAR TERM: WINDS/SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY
LEVELS TONIGHT THROUGH WEDNESDAY. VISIBILITIES WILL BE REDUCED IN
FOG TONIGHT THROUGH WEDNESDAY...ALONG WITH SHOWERS AND
THUNDERSTORMS.
SHORT TERM: FOG CONTINUES UNTIL THURSDAY MORNING. LOWER PERIOD SE
SWELL NEAR 4 FT IS EXPECTED WEDNESDAY NIGHT INTO THURSDAY.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...DUDA
SHORT TERM...MCW
LONG TERM...BLOOMER
AVIATION...DUDA/MCW
MARINE...DUDA/MCW
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
454 PM EDT WED AUG 26 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 350 PM EDT WED AUG 26 2015
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW THAT THE MID LEVEL LOW
THAT HAS PLAGUED UPPER MI FOR THE LAST 2 DAYS WITH UNSEASONABLY COOL
WEATHER IS NOW CENTERED SE OF JAMES BAY AND IS CONTINUING TO DRIFT
E. UPSTREAM...A RIDGE EXTENDS FROM THE SRN ROCKIES INTO
SASKATCHEWAN/MANITOBA/NRN ONTARIO. VIS SATELLITE IMAGERY SHOWS THE
BACK EDGE OF THE LOW CLOUDS ASSOCIATED WITH LOW AND DEPARTING
THERMAL TROF RUNNING FROM ROUGHLY COPPER HARBOR TO MARQUETTE TO IRON
MTN. TO THE W...ELEVATED SMOKE LAYER FROM THE PACIFIC NW FOREST
FIRES IS ONCE AGAIN SPREADING ACROSS THE NRN PLAINS WITH LEADING
EDGE APPROACHING WRN LAKE SUPERIOR/FAR NW WI.
SHORT TERM PORTION OF THE FCST WILL BE QUIET AS SFC HIGH PRES RIDGE
MOVES ACROSS THE UPPER LAKES TONIGHT AND CONTINUES TO DRIFT EASTWARD
ON THU. MAIN FCST ISSUES WILL REVOLVE AROUND CLOUDS/TEMPS AND
FROST/FOG POTENTIAL TONIGHT. EXPECT CLOUDS TO CONTINUE CLEARING OUT
FROM NW TO SE OVER THE NEXT SEVERAL HRS. HOWEVER...THERE IS
CERTAINLY CONCERN THAT CLEARING MAY NOT PROGRESS FAR ENOUGH SE
BEFORE LOW-LEVEL WINDS VEER AND EITHER HOLD CLOUDS IN OVER THE E OR
BRING THEM BACK. FOR NOW...THE PLAN IS FOR DAYTIME HEATING TO
CONTINUE MIXING OUT THE MOISTURE FROM THE W AND AID THE CURRENT SE
CLEARING TREND...HELPING IT PROGRESS FAR ENOUGH THAT CLOUDS WILL
STAY E OF THE FCST AREA TONIGHT. IF CLOUDS DO NOT CLEAR OUT OF THE
ERN FCST AREA BY SUNSET...SKIES PROBABLY WON`T CLEAR TONIGHT.
OTHERWISE...AS SFC HIGH PRES SLOWLY MOVES ACROSS THE FCST AREA
TONIGHT...STAGE WILL BE SET FOR A COOL NIGHT UNDER CLEAR SKIES/CALM
WIND AND DRY AIR MASS WITH PRECIPITABLE AROUND ONE-HALF INCH. LEANED
FCST SIGNIFICANTLY TOWARD BOTH BIAS CORRECTED CANADIAN MODELS FOR
MINS DUE TO THEIR USUAL BETTER PERFORMANCE IN RADIATIONAL COOLING
SITUATIONS. EXPECT THE NORMAL COLD AREAS IN THE INTERIOR TO FALL
INTO THE UPPER 30S WITH TRADITIONAL COLD SPOTS DOWN INTO THE MID
30S. WILL INCLUDE PATCHY FROST IN THE FCST. TYPICAL FOR THIS TIME OF
YEAR UNDER RADIATIONAL COOLING CONDITIONS...EXPECT SOME FOG TO
DEVELOP AS WELL NEAR RIVERS/STREAMS/LAKES/SWAMPY AREAS.
RETURN FLOW WILL BEGIN ON THU AS THE SFC HIGH PRES RIDGE CONTINUES
TO DRIFT E. WITH LINGERING DRY AIR MASS...EXPECT ONLY SOME HIGH
CLOUDS...THOUGH SKY WILL LIKELY BE HAZY WITH ELEVATED SMOKE LAYER
OVER THE UPPER LAKES. WITH MORNING 850MB TEMPS OF 10-12C AND RISING
1-2C DURING THE DAY...EXPECT AFTN MAX TEMPS MOSTLY IN THE LOWER TO
MIDDLE 70S AWAY FROM ANY LAKE MODERATION.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 453 PM EDT WED AUG 26 2015
THE MODELS WERE IN OVERALL AGREEMENT WITH THE PATTERN TRANSITION
FROM ZONAL FLOW TO A MORE AMPLIFIED PATTERN NEXT WEEK WITH A TROUGH
OVER THE NW CONUS AND A RIDGE OVER THE CNTRL AND EAST.
THURSDAY NIGHT...AS THE SFC RIDGE SLIDES OFF TO THE EAST AND 850-700
MB WAA DEVELOPS...EXPECT SOME INCREASE IN MID CLOUDS ACROSS UPPER
MICHIGAN. THIS SHOULD HELP KEEP OVERNIGHT LOWS IN THE MID 50S INLAND
TO AROUND 60 NEAR LAKE SUPERIOR WHERE DOWNSLOPE FLOW PREVAILS.
FRI THROUGH SAT...THERE IS STILL PLENTY OF UNCERTAINTY WITH THE
PATH/TIMING OF THE SHORTWAVE EMERGING FROM THE PLAINS. THE
GFS...GEM AND ESPECIALLY THE ECMWF HAVE TRENDED FARTHER NORTH WITH
THE SYSTEM WHICH COULD REMAIN JUST SOUTH OF THE CWA OR BRING RAIN TO
MOST OF THE AREA. THE FCST REFLECTS THESE TRENDS AND REMAINING
UNCERTAINTY WITH INCREASING POPS THAT REMAIN IN THE CHANCE CATEGORY.
THE BEST CHANCE FOR RAIN WOULD ARRIVE MAINLY FRI NIGHT AND LINGER
OVER THE ERN CWA AT LEAST THROUGH SAT MORNING. THERE MAY ENOUGH
HEATING/INSTABILITY FRI FOR AT LEAST A MENTION OF TSRA...BUT MOST OF
THE PCPN ASSOCIATED WITH THE SHRTWV WILL NOT HAVE TS...PER GFS/ECMWF
INSTABILITY PROGS.
SAT NIGHT THROUGH WED...THE BUILDING RIDGE WILL BRING WARMER
CONDITIONS WITH MAINLY DRY CONDITIONS. EXPECT THE FRONTAL BOUNDARY
TO REMAIN FAR ENOUGH WEST TO MINIMIZE SHRA/TSRA CHANCES. HIGHS WILL
CLIMB WELL ABOVE NORMAL WITH HIGHS WELL INTO THE 80S FROM MON
THROUGH WED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 143 PM EDT WED AUG 26 2015
HIGH PRES AND DRIER AIR BUILDING INTO THE UPPER GREAT LAKES WILL
RESULT IN CLEARING SKIES THIS AFTN. KIWD HAS ALREADY CLEARED
OUT...AND VFR CONDITIONS/LIGHT WINDS WILL PREVAIL THERE THRU THIS
FCST PERIOD. AT KCMX/KSAW...MVFR CIGS WILL CLEAR OUT IN THE NEXT
COUPLE OF HRS...LEAVING VFR CONDITIONS TO PREVAIL FOR THE REMAINDER
OF THE FCST PERIOD. HOWEVER...CONDITIONS TONIGHT WILL BE CONDUCIVE
FOR SHALLOW RADIATION FOG DEVELOPMENT. FOG COULD AFFECT ANY OF THE
TERMINALS...BUT FOR NOW...INCLUDED MVFR VIS LATE TONIGHT ONLY AT
KSAW WITH CONDITIONS MORE FAVORABLE AT THAT TERMINAL. ITS QUITE
POSSIBLE THAT IFR OR LIFR CONDITIONS WILL BE THE RESULT IF FOG
DOES DEVELOP AT ANY OF THE TERMINALS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 350 PM EDT WED AUG 26 2015
WITH SFC HIGH PRES OVER THE UPPER GREAT LAKES...WINDS WILL BE LESS
THAN 15KT ACROSS LAKE SUPERIOR TONIGHT. ALTHOUGH THE HIGH DRIFTS E
ON THU...WINDS WILL REMAIN UNDER 15KT THOUGH LOCALLY SLIGHTLY HIGHER
E TO SE WINDS ARE POSSIBLE IN THE AFTN IN THE VCNTY OF THE HURON
ISLANDS. WINDS SHOULD REMAIN UNDER 20KT THRU THE WEEKEND...BUT THERE
MAY BE SOME PERIODS WHERE WIND GUSTS EXCEED 20KT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLB
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
351 PM EDT WED AUG 26 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 350 PM EDT WED AUG 26 2015
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW THAT THE MID LEVEL LOW
THAT HAS PLAGUED UPPER MI FOR THE LAST 2 DAYS WITH UNSEASONABLY COOL
WEATHER IS NOW CENTERED SE OF JAMES BAY AND IS CONTINUING TO DRIFT
E. UPSTREAM...A RIDGE EXTENDS FROM THE SRN ROCKIES INTO
SASKATCHEWAN/MANITOBA/NRN ONTARIO. VIS SATELLITE IMAGERY SHOWS THE
BACK EDGE OF THE LOW CLOUDS ASSOCIATED WITH LOW AND DEPARTING
THERMAL TROF RUNNING FROM ROUGHLY COPPER HARBOR TO MARQUETTE TO IRON
MTN. TO THE W...ELEVATED SMOKE LAYER FROM THE PACIFIC NW FOREST
FIRES IS ONCE AGAIN SPREADING ACROSS THE NRN PLAINS WITH LEADING
EDGE APPROACHING WRN LAKE SUPERIOR/FAR NW WI.
SHORT TERM PORTION OF THE FCST WILL BE QUIET AS SFC HIGH PRES RIDGE
MOVES ACROSS THE UPPER LAKES TONIGHT AND CONTINUES TO DRIFT EASTWARD
ON THU. MAIN FCST ISSUES WILL REVOLVE AROUND CLOUDS/TEMPS AND
FROST/FOG POTENTIAL TONIGHT. EXPECT CLOUDS TO CONTINUE CLEARING OUT
FROM NW TO SE OVER THE NEXT SEVERAL HRS. HOWEVER...THERE IS
CERTAINLY CONCERN THAT CLEARING MAY NOT PROGRESS FAR ENOUGH SE
BEFORE LOW-LEVEL WINDS VEER AND EITHER HOLD CLOUDS IN OVER THE E OR
BRING THEM BACK. FOR NOW...THE PLAN IS FOR DAYTIME HEATING TO
CONTINUE MIXING OUT THE MOISTURE FROM THE W AND AID THE CURRENT SE
CLEARING TREND...HELPING IT PROGRESS FAR ENOUGH THAT CLOUDS WILL
STAY E OF THE FCST AREA TONIGHT. IF CLOUDS DO NOT CLEAR OUT OF THE
ERN FCST AREA BY SUNSET...SKIES PROBABLY WON`T CLEAR TONIGHT.
OTHERWISE...AS SFC HIGH PRES SLOWLY MOVES ACROSS THE FCST AREA
TONIGHT...STAGE WILL BE SET FOR A COOL NIGHT UNDER CLEAR SKIES/CALM
WIND AND DRY AIR MASS WITH PRECIPITABLE AROUND ONE-HALF INCH. LEANED
FCST SIGNIFICANTLY TOWARD BOTH BIAS CORRECTED CANADIAN MODELS FOR
MINS DUE TO THEIR USUAL BETTER PERFORMANCE IN RADIATIONAL COOLING
SITUATIONS. EXPECT THE NORMAL COLD AREAS IN THE INTERIOR TO FALL
INTO THE UPPER 30S WITH TRADITIONAL COLD SPOTS DOWN INTO THE MID
30S. WILL INCLUDE PATCHY FROST IN THE FCST. TYPICAL FOR THIS TIME OF
YEAR UNDER RADIATIONAL COOLING CONDITIONS...EXPECT SOME FOG TO
DEVELOP AS WELL NEAR RIVERS/STREAMS/LAKES/SWAMPY AREAS.
RETURN FLOW WILL BEGIN ON THU AS THE SFC HIGH PRES RIDGE CONTINUES
TO DRIFT E. WITH LINGERING DRY AIR MASS...EXPECT ONLY SOME HIGH
CLOUDS...THOUGH SKY WILL LIKELY BE HAZY WITH ELEVATED SMOKE LAYER
OVER THE UPPER LAKES. WITH MORNING 850MB TEMPS OF 10-12C AND RISING
1-2C DURING THE DAY...EXPECT AFTN MAX TEMPS MOSTLY IN THE LOWER TO
MIDDLE 70S AWAY FROM ANY LAKE MODERATION.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 336 AM EDT WED AUG 26 2015
AFTER A PERIOD OF VERY COOL WX...LOOKS LIKE A RETURN OF MORE
SEASONABLE WX TO END THE WEEK. ALTHOUGH THERE MAY BE SOME SHOWERS
LATE THU NGT INTO SAT...PCPN CHCS APPEAR LIMITED BY THE PLACEMENT OF
UPR MI BTWN DISTURBANCES PASSING TO THE N AND S OF THE UPR LKS. A
RETURN OF SUMMER-LIKE WX APPEARS ON TAP NEXT WEEK AS AN UPR RDG IS
FCST TO BUILD OVER THE GREAT LKS DOWNSTREAM OF A DEEPENING TROF
ACROSS THE W.
THU...EXPECT A MOSUNNY AND WARMER DAY ON THU WITH HI PRES/ACYC SW
FLOW/DRY AIRMASS DOMINATING. H85 TEMPS REBOUNDING TO 12-14C BY LATE
IN THE DAY WL SUPPORT MAX TEMPS RISING WELL INTO THE 70S OVER MOST
OF THE CWA AWAY FM LK MI MODERATION.
THU NGT...UPR MI IS FCST TO BE SITUATED BTWN FAST WNW FLOW OVER SRN
CANADA AND A WEAKER SRN STREAM OVER THE CENTRAL CONUS. A DISTURBANCE
IN THE NRN STREAM IS FCST TO SLIDE ESEWD THRU ONTARIO DURING THE NGT
WITH ATTENDANT COLD FNT APRCHG NW LK SUP LATE. AT THE SAME TIME...A
SHRTWV IN THE SRN BRANCH WL BE DRIFTING SLOWLY ESEWD THRU THE MID/
UPR MS RIVER VALLEY. ALTHOUGH THE 12Z ECMWF GENERATED SOME SPOTTY
LGT PCPN OVER THE NW HALF OF UPR MI LATE AT NGT WITH THE RETURN OF
SOME HIER H85 THETA E AIR IN THE WLY FLOW TO THE S OF DISTURBANCE
PASSING THRU ONTARIO...AXIS OF WEAK FORCING/LINGERING LLVL ACYC FLOW
OVER UPR MI BTWN AREAS OF SHARPER DYNAMIC FORCING/CYC FLOW PASSING
TO THE S AND THE N AS WELL AS NOCTURNAL COOLING FAVOR THE DRIER
MODELS. SO CUT POPS TO NO HIER THAN LO CHC NEAR ISLE ROYALE CLOSER
TO APRCHG COLD FNT.
FRI THRU SAT...RECENT MODEL GUIDANCE HAS SHOWN SOME UNCERTAINTY ON
HOW FAR S COLD FNT ASSOCIATED WITH EXITING NRN BRANCH SHRTWV WL
REACH/BECOME STNRY AND ALSO ON TRACK OF SRN BRANCH DISTURBANCE/NRN
EDGE OF ACCOMPANYING PCPN SHIELD. GIVEN THE BLDG UPR RDG IN THE
PLAINS THAT WL FAVOR A MORE WNW FLOW ALOFT OVER THE UPR LKS...
SUSPECT THE 00Z ECMWF/18Z GFS SHOWING A FARTHER N PCPN AREA ARE OFF
THE MARK AND THAT THE FARTHER S TRACK OF THE SRN BRANCH DISTURBANCE
IS CORRECT WITH ACCOMPANYING PCPN REMAINING TO THE S OF UPR MI.
SEEMS THE BEST CHC FOR PCPN WL BE IF ANOTHER SHRTWV IN THE NRN
BRANCH FLOW OVER SCENTRAL CANADA DRIFTS CLOSE ENUF TO THE STNRY FNT
ALIGNED W-E SOMEWHERE IN THE UPR LKS TO TRIGGER SOME SHOWERS/PERHAPS
A TS OVER UPR MI. SINCE THE BULK OF THE MODELS SHOW THE SFC FNT
POSITIONED TO THE N OF THE CWA WITH LINGERING AXIS OF LLVL ACYC FLOW
OVER UPR MI...TENDED TO GO NO HIER THAN LO CHC POPS. WITH H85 TEMPS
WITHIN A FEW DEGREES OF 14C...EXPECT TEMPS TO AVG A BIT ABOVE NORMAL.
SAT NGT THRU TUE...BLDG UPR RDG DOWNSTREAM OF AMPLIFYING TROF OVER
WRN NAMERICA IS FCST TO DOMINATE THE GREAT LKS...BRINGING A PERIOD
OF DRY AND WARMER WX AS A LLVL ACYC SW FLOW ARND SFC HI PRES
CENTERED OVER THE MID ATLANTIC STATES PREVAILS. H85 TEMPS FCST TO
REACH 16-20C ON SUN AND THEN AOA 20C ON MON WL SUPPORT MAX TEMPS
WELL INTO THE 80S. ALTHOUGH SOME OF THE LONGER RANGE GUIDANCE HINTS
A COLD FNT ASSOCIATED WITH A SHRTWV RIDING OVER THE UPR RDG MAY
APRCH OR PASS NEXT TUE AND BRING SOME SHOWERS/TS AS EARLY AS LATE
MON...WL GO NO HIER THAN LO CHC POPS GIVEN THE EXPECTED STRENGTH OF
THE UPR RDG.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 143 PM EDT WED AUG 26 2015
HIGH PRES AND DRIER AIR BUILDING INTO THE UPPER GREAT LAKES WILL
RESULT IN CLEARING SKIES THIS AFTN. KIWD HAS ALREADY CLEARED
OUT...AND VFR CONDITIONS/LIGHT WINDS WILL PREVAIL THERE THRU THIS
FCST PERIOD. AT KCMX/KSAW...MVFR CIGS WILL CLEAR OUT IN THE NEXT
COUPLE OF HRS...LEAVING VFR CONDITIONS TO PREVAIL FOR THE REMAINDER
OF THE FCST PERIOD. HOWEVER...CONDITIONS TONIGHT WILL BE CONDUCIVE
FOR SHALLOW RADIATION FOG DEVELOPMENT. FOG COULD AFFECT ANY OF THE
TERMINALS...BUT FOR NOW...INCLUDED MVFR VIS LATE TONIGHT ONLY AT
KSAW WITH CONDITIONS MORE FAVORABLE AT THAT TERMINAL. ITS QUITE
POSSIBLE THAT IFR OR LIFR CONDITIONS WILL BE THE RESULT IF FOG
DOES DEVELOP AT ANY OF THE TERMINALS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 350 PM EDT WED AUG 26 2015
WITH SFC HIGH PRES OVER THE UPPER GREAT LAKES...WINDS WILL BE LESS
THAN 15KT ACROSS LAKE SUPERIOR TONIGHT. ALTHOUGH THE HIGH DRIFTS E
ON THU...WINDS WILL REMAIN UNDER 15KT THOUGH LOCALLY SLIGHTLY HIGHER
E TO SE WINDS ARE POSSIBLE IN THE AFTN IN THE VCNTY OF THE HURON
ISLANDS. WINDS SHOULD REMAIN UNDER 20KT THRU THE WEEKEND...BUT THERE
MAY BE SOME PERIODS WHERE WIND GUSTS EXCEED 20KT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KC
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
339 AM EDT WED AUG 26 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 411 PM EDT TUE AUG 25 2015
LATEST WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A DEEP MID LEVEL
LOW CENTERED N OF GEORGIAN BAY DRIFTING EASTWARD. TO THE W...A RIDGE
EXTENDS FROM THE SRN ROCKIES N INTO SASKATCHEWAN/MANITOBA. IN THE
LINGERING MOIST...CYCLONIC FLOW AROUND THE MID LEVEL LOW...SOME
-SHRA/-DZ HAVE PERSISTED ACROSS THE FCST AREA TODAY...AIDED BY NW
UPSLOPE FLOW. THERE HAS PROBABLY BEEN SOME LAKE COMPONENT TO THE
PCPN AS WELL. WITH CLOUD TOPS WARMING OVER THE LAST SEVERAL HRS PER
IR IMAGERY...RADAR HAS SHOWN PCPN COVERAGE/INTENSITY DIMINISHING.
UNDER AN OVC CLOUD COVER...IT HAS BEEN ANOTHER UNSEASONABLY COOL DAY
FOR LATE AUG. SO FAR...TEMPS HAVE ONLY RISEN TO THE LOW/MID 50S IN
THE HIGHER TERRAIN AND WHERE PCPN LINGERS TO AROUND 60 OVER THE FAR
SCNTRL. BACK EDGE OF THE CLOUD COVER EXTENDS ROUGHLY FROM DULUTH TO
INTERNATIONAL FALLS AND NORTHWARD.
AS MID LEVEL LOW AND UPSTREAM RIDGE DRIFT E...EXPECT IMPROVING
CONDITIONS DURING THE SHORT TERM PORTION OF THE FCST. MAIN FCST
ISSUES WILL BE TIMING THE ENDING OF PCPN AND THE CLEARING TREND.
UNDER SLOW HEIGHT RISES/DEEP LAYER QVECTOR DIVERGENCE AND WEAKENING
CYCLONIC FLOW...LINGERING -SHRA/-DZ WILL CONTINUE TO DIMINISH
TONIGHT. THIS TREND WILL BE MOST PRONOUNCED OVER THE W...WHERE THE
LOW-LEVEL FLOW BECOMES MORE ANTICYCLONIC CLOSER TO APPROACHING SFC
HIGH PRES SETTLING OVER MN. LINGERING LOW CLOUDS WILL LIMIT TEMP
FALL TONIGHT. EXPECT THE LOWEST MINS (TOWARD THE MID 40S) OVER THE
INTERIOR W...WHERE THERE COULD BE SOME PARTIAL CLEARING LATE. IF
THERE IS SOME CLEARING...PATCHY FOG COULD DEVELOP.
A FEW -SHRA/PATCHY -DZ MAY CONTINUE TO LINGER INTO THE NCNTRL/ERN
FCST AREA WED MORNING UNDER ABUNDANT LOW-LEVEL MOISTURE. WITH
NEUTRAL TO VERY WEAKLY CYCLONIC LOW-LEVEL FLOW AND AIR MASS TOO WARM
FOR LAKE EFFECT PROCESSES...ANY PCPN WILL BE VERY LIGHT.
OTHERWISE...APPROACHING HIGH PRES WILL SETTLE OVER UPPER MI BY WED
EVENING. MODELS SUGGEST CLEARING WILL ONLY SLOWLY PUSH E ACROSS THE
FCST AREA AS THE HIGH ARRIVES AND THERMAL TROF DEPARTS. LARGELY
UTILIZED A MODEL CONSENSUS TO CONSTRUCT THE SKY COVER AND THE W TO E
CLEARING TREND ON WED. IT MAY NOT BE UNTIL TOWARD SUNSET THAT THE
LAST OF THE CLOUDS CLEAR THE ERN FCST AREA. UNDER INCREASING
SUNSHINE AND DEPARTURE OF THERMAL TROF...TEMPS WILL BEGIN TO
REBOUND. EXPECT HIGHS AROUND 60/LWR 60S E WHERE CLOUDS LINGER
LONGEST TO THE UPPER 60S TOWARD THE MI/WI BORDER.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 336 AM EDT WED AUG 26 2015
AFTER A PERIOD OF VERY COOL WX...LOOKS LIKE A RETURN OF MORE
SEASONABLE WX TO END THE WEEK. ALTHOUGH THERE MAY BE SOME SHOWERS
LATE THU NGT INTO SAT...PCPN CHCS APPEAR LIMITED BY THE PLACEMENT OF
UPR MI BTWN DISTURBANCES PASSING TO THE N AND S OF THE UPR LKS. A
RETURN OF SUMMER-LIKE WX APPEARS ON TAP NEXT WEEK AS AN UPR RDG IS
FCST TO BUILD OVER THE GREAT LKS DOWNSTREAM OF A DEEPENING TROF
ACROSS THE W.
THU...EXPECT A MOSUNNY AND WARMER DAY ON THU WITH HI PRES/ACYC SW
FLOW/DRY AIRMASS DOMINATING. H85 TEMPS REBOUNDING TO 12-14C BY LATE
IN THE DAY WL SUPPORT MAX TEMPS RISING WELL INTO THE 70S OVER MOST
OF THE CWA AWAY FM LK MI MODERATION.
THU NGT...UPR MI IS FCST TO BE SITUATED BTWN FAST WNW FLOW OVER SRN
CANADA AND A WEAKER SRN STREAM OVER THE CENTRAL CONUS. A DISTURBANCE
IN THE NRN STREAM IS FCST TO SLIDE ESEWD THRU ONTARIO DURING THE NGT
WITH ATTENDANT COLD FNT APRCHG NW LK SUP LATE. AT THE SAME TIME...A
SHRTWV IN THE SRN BRANCH WL BE DRIFTING SLOWLY ESEWD THRU THE MID/
UPR MS RIVER VALLEY. ALTHOUGH THE 12Z ECMWF GENERATED SOME SPOTTY
LGT PCPN OVER THE NW HALF OF UPR MI LATE AT NGT WITH THE RETURN OF
SOME HIER H85 THETA E AIR IN THE WLY FLOW TO THE S OF DISTURBANCE
PASSING THRU ONTARIO...AXIS OF WEAK FORCING/LINGERING LLVL ACYC FLOW
OVER UPR MI BTWN AREAS OF SHARPER DYNAMIC FORCING/CYC FLOW PASSING
TO THE S AND THE N AS WELL AS NOCTURNAL COOLING FAVOR THE DRIER
MODELS. SO CUT POPS TO NO HIER THAN LO CHC NEAR ISLE ROYALE CLOSER
TO APRCHG COLD FNT.
FRI THRU SAT...RECENT MODEL GUIDANCE HAS SHOWN SOME UNCERTAINTY ON
HOW FAR S COLD FNT ASSOCIATED WITH EXITING NRN BRANCH SHRTWV WL
REACH/BECOME STNRY AND ALSO ON TRACK OF SRN BRANCH DISTURBANCE/NRN
EDGE OF ACCOMPANYING PCPN SHIELD. GIVEN THE BLDG UPR RDG IN THE
PLAINS THAT WL FAVOR A MORE WNW FLOW ALOFT OVER THE UPR LKS...
SUSPECT THE 00Z ECMWF/18Z GFS SHOWING A FARTHER N PCPN AREA ARE OFF
THE MARK AND THAT THE FARTHER S TRACK OF THE SRN BRANCH DISTURBANCE
IS CORRECT WITH ACCOMPANYING PCPN REMAINING TO THE S OF UPR MI.
SEEMS THE BEST CHC FOR PCPN WL BE IF ANOTHER SHRTWV IN THE NRN
BRANCH FLOW OVER SCENTRAL CANADA DRIFTS CLOSE ENUF TO THE STNRY FNT
ALIGNED W-E SOMEWHERE IN THE UPR LKS TO TRIGGER SOME SHOWERS/PERHAPS
A TS OVER UPR MI. SINCE THE BULK OF THE MODELS SHOW THE SFC FNT
POSITIONED TO THE N OF THE CWA WITH LINGERING AXIS OF LLVL ACYC FLOW
OVER UPR MI...TENDED TO GO NO HIER THAN LO CHC POPS. WITH H85 TEMPS
WITHIN A FEW DEGREES OF 14C...EXPECT TEMPS TO AVG A BIT ABOVE NORMAL.
SAT NGT THRU TUE...BLDG UPR RDG DOWNSTREAM OF AMPLIFYING TROF OVER
WRN NAMERICA IS FCST TO DOMINATE THE GREAT LKS...BRINGING A PERIOD
OF DRY AND WARMER WX AS A LLVL ACYC SW FLOW ARND SFC HI PRES
CENTERED OVER THE MID ATLANTIC STATES PREVAILS. H85 TEMPS FCST TO
REACH 16-20C ON SUN AND THEN AOA 20C ON MON WL SUPPORT MAX TEMPS
WELL INTO THE 80S. ALTHOUGH SOME OF THE LONGER RANGE GUIDANCE HINTS
A COLD FNT ASSOCIATED WITH A SHRTWV RIDING OVER THE UPR RDG MAY
APRCH OR PASS NEXT TUE AND BRING SOME SHOWERS/TS AS EARLY AS LATE
MON...WL GO NO HIER THAN LO CHC POPS GIVEN THE EXPECTED STRENGTH OF
THE UPR RDG.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 121 AM EDT WED AUG 26 2015
A CONTINUED NW FLOW OF MOIST COOL AIR AROUND LOW PRES NE OF LAKE
SUPERIOR WILL ALLOW MVFR CONDITIONS TO PERSIST AT KIWD/KCMX/KSAW
THRU AT LEAST THE OVERNIGHT. EXPECT PATCHY -DZ AT KSAW INTO THE
MORNING HOURS...BUT SHOULDN`T REDUCE VIS BLO VFR. AS HIGH PRES
CONTINUES TO BUILD INTO THE AREA TODAY...MVFR CIGS WILL SCATTER OUT
AT KIWD/KCMX IN THE MORNING WHILE CLEARING WILL OCCUR LATER IN THE
AFTN AT KSAW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 411 PM EDT TUE AUG 25 2015
WITH LOW PRES NEAR JAMES BAY CONTINUING TO MOVE AWAY FROM THE AREA
AND HIGH PRES OVER THE PLAINS APPROACHING...WINDS WILL CONTINUE TO
DIMINISH ACROSS LAKE SUPERIOR FROM W TO E TONIGHT AND WED. WINDS
TONIGHT WILL GENERALLY RANGE FROM 10-20KT W TO 15-30KT E. WINDS ON
WED WILL DIMINISH TO UNDER 15KT W AND UNDER 20KT E BY THE END OF THE
AFTN. AS THE HIGH MOVES OVER THE UPPER LAKES WED NIGHT...WINDS WILL
BE UNDER 15KT ACROSS LAKE SUPERIOR. WINDS WILL BE MOSTLY UNDER 20KT
THU THRU SUN.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KC
AVIATION...VOSS
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
122 AM EDT WED AUG 26 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 411 PM EDT TUE AUG 25 2015
LATEST WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A DEEP MID LEVEL
LOW CENTERED N OF GEORGIAN BAY DRIFTING EASTWARD. TO THE W...A RIDGE
EXTENDS FROM THE SRN ROCKIES N INTO SASKATCHEWAN/MANITOBA. IN THE
LINGERING MOIST...CYCLONIC FLOW AROUND THE MID LEVEL LOW...SOME
-SHRA/-DZ HAVE PERSISTED ACROSS THE FCST AREA TODAY...AIDED BY NW
UPSLOPE FLOW. THERE HAS PROBABLY BEEN SOME LAKE COMPONENT TO THE
PCPN AS WELL. WITH CLOUD TOPS WARMING OVER THE LAST SEVERAL HRS PER
IR IMAGERY...RADAR HAS SHOWN PCPN COVERAGE/INTENSITY DIMINISHING.
UNDER AN OVC CLOUD COVER...IT HAS BEEN ANOTHER UNSEASONABLY COOL DAY
FOR LATE AUG. SO FAR...TEMPS HAVE ONLY RISEN TO THE LOW/MID 50S IN
THE HIGHER TERRAIN AND WHERE PCPN LINGERS TO AROUND 60 OVER THE FAR
SCNTRL. BACK EDGE OF THE CLOUD COVER EXTENDS ROUGHLY FROM DULUTH TO
INTERNATIONAL FALLS AND NORTHWARD.
AS MID LEVEL LOW AND UPSTREAM RIDGE DRIFT E...EXPECT IMPROVING
CONDITIONS DURING THE SHORT TERM PORTION OF THE FCST. MAIN FCST
ISSUES WILL BE TIMING THE ENDING OF PCPN AND THE CLEARING TREND.
UNDER SLOW HEIGHT RISES/DEEP LAYER QVECTOR DIVERGENCE AND WEAKENING
CYCLONIC FLOW...LINGERING -SHRA/-DZ WILL CONTINUE TO DIMINISH
TONIGHT. THIS TREND WILL BE MOST PRONOUNCED OVER THE W...WHERE THE
LOW-LEVEL FLOW BECOMES MORE ANTICYCLONIC CLOSER TO APPROACHING SFC
HIGH PRES SETTLING OVER MN. LINGERING LOW CLOUDS WILL LIMIT TEMP
FALL TONIGHT. EXPECT THE LOWEST MINS (TOWARD THE MID 40S) OVER THE
INTERIOR W...WHERE THERE COULD BE SOME PARTIAL CLEARING LATE. IF
THERE IS SOME CLEARING...PATCHY FOG COULD DEVELOP.
A FEW -SHRA/PATCHY -DZ MAY CONTINUE TO LINGER INTO THE NCNTRL/ERN
FCST AREA WED MORNING UNDER ABUNDANT LOW-LEVEL MOISTURE. WITH
NEUTRAL TO VERY WEAKLY CYCLONIC LOW-LEVEL FLOW AND AIR MASS TOO WARM
FOR LAKE EFFECT PROCESSES...ANY PCPN WILL BE VERY LIGHT.
OTHERWISE...APPROACHING HIGH PRES WILL SETTLE OVER UPPER MI BY WED
EVENING. MODELS SUGGEST CLEARING WILL ONLY SLOWLY PUSH E ACROSS THE
FCST AREA AS THE HIGH ARRIVES AND THERMAL TROF DEPARTS. LARGELY
UTILIZED A MODEL CONSENSUS TO CONSTRUCT THE SKY COVER AND THE W TO E
CLEARING TREND ON WED. IT MAY NOT BE UNTIL TOWARD SUNSET THAT THE
LAST OF THE CLOUDS CLEAR THE ERN FCST AREA. UNDER INCREASING
SUNSHINE AND DEPARTURE OF THERMAL TROF...TEMPS WILL BEGIN TO
REBOUND. EXPECT HIGHS AROUND 60/LWR 60S E WHERE CLOUDS LINGER
LONGEST TO THE UPPER 60S TOWARD THE MI/WI BORDER.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 301 PM EDT TUE AUG 25 2015
GOOD AGREEMENT IN OVERALL LOOK OF LARGE SCALE PATTERN INTO NEXT
WEEK. UPPER TROUGHING WITH SLOW MOVING SFC LOW REORGANIZES INTO
UPPER LOW OVER HUDSON BAY AND NUNAVUT CANADA BY END OF THE WEEK.
EXPECT UPPER RIDGE OVER PACIFIC NORTHWEST TO THE ROCKIES EARLY THIS
WEEK TO MOVE ACROSS THE PLAINS TO THE WESTERN GREAT LAKES BY THIS
WEEKEND AS TROUGHING DEEPENS AND SETTLES ACROSS WESTERN CANADA AND
THE PACIFIC NORTHWEST. CHANCES FOR MUCH RAINFALL IN THIS PATTERN ARE
SLIM.
STARTING WITH WEDNESDAY NIGHT...HIGH PRESSURE RIDGE SETTLES ACROSS
THE AREA SO WINDS WILL BECOME LIGHT. THE LIGHT WINDS AND PWATS DOWN
BLO 0.5 INCH SHOULD LEAD TO GOOD RADIATIONAL COOLING. LOWERED MINS
INTO THE MIDDLE 30S FOR TYPICAL COLD SPOTS OVER INTERIOR. SOUNDINGS
SHOW LOW-LEVEL MOISTENING AS WELL SO THERE MAY BE FOG. ALSO ADDED
MENTION OF FROST FOR COLDEST SPOTS. THIS NIGHT APPEARS TO BE TAIL
END OF THE FALL LIKE CONDITIONS BEFORE WARMING TREND STARTS UP ON
THURSDAY.
ONLY NOTABLE CHANCES OF RAIN WOULD BE LATE THURSDAY NIGHT INTO
FRIDAY AS WEAK COLD FRONT MAKES BRIEF PUSH ACROSS NORTHWEST ONTARIO
AND THE UPPER GREAT LAKES. LARGER SCALE SUPPORT NOT VERY STRONG FOR
RAIN OVER UPR MICHIGAN AS UPPER LEVEL SHORTWAVE ENERGY IS GENERALLY
DISPLACED OF UPPER LAKES WITH ONE STRONGER SHORTWAVE CROSSING WELL
TO THE NORTH OVER NORTHERN MANITOBA AND NORTHERN ONTARIO AND OTHER
STRONGER SHORTWAVE SLIDING FM WYOMING/NEBRASKA TO IOWA/NORTHERN
ILLINOIS. RESULT IS STRONGEST Q-VECTOR CONVERGENCE/LIFT STAYING OVER
NORTHERN ONTARIO AND FM SOUTHERN MINNESOTA TO WISCONSIN AND LOWER
MICHIGAN. APPEARS THAT GREATEST MOISTURE INFLOW IN FORM OF H85
THETA-E ADVECTION IS INTERCEPTED BY SOUTHERN SHORTWAVE. NO HELP FM
INSTABILITY WITH STRONGER MUCAPE STAYING OVER THE NORTHERN PLAINS
THURSDAY NIGHT INTO FRIDAY. BETTER SIGNAL FOR CONVECTION RUNS FM
SOUTHERN MINNESOTA TO SOUTHERN WISCONSIN CLOSER TO H85 MOISTURE
TRANSPORT. LOWER RANGE CHANCE POPS IS ALL THAT THIS FRONTAL BOUNDARY
WARRANTS ATTM FOR THURSDAY NIGHT INTO FRIDAY.
WEAKNESS IN THE UPPER LEVEL FLOW...VERY WEAK TROUGHING...LINGERS
OVER THE WESTERN GREAT LAKES ON SATURDAY. GFS SOUNDINGS SHOW NARROW
LAYER OF LOW-LEVEL MOISTURE BUT THIS IS PROBABLY NOT ENOUGH TO
SUPPORT SHOWERS. PROBABLY WILL BE SOME SORT OF ONSHORE COMPONENT TO
THE WINDS OVER THE EAST HALF OF CWA CLOSER TO HIGH PRESSURE OVER
MUCH OF THE GREAT LAKES. WEST HALF OF CWA SHOULD START TO SEE MORE
S/SW WINDS AHEAD OF DEVELOPING TROUGHING IN THE PLAINS. H85 TEMPS
COOL A FEW DEGREES COMPARED TO FRIDAY. WARMEST TEMPS ON SATURDAY IN
THE LOW-MID 70S SHOULD BE OVER THE WEST WITH LESS INFLUENCE OF GREAT
LAKES COOLING AND BETTER CHANCES OF SEEING SOME SUNSHINE. UPPER
LEVEL RIDGING TAKES BETTER HOLD ON SUNDAY. SFC WINDS REMAIN LIGHT AS
SFC RIDGE IS STILL CLOSE BY TO THE EAST. WITH H85 TEMPS WARMING TO
13-15C...SHOULD SEE READINGS MOST AREAS AT LEAST INTO THE UPPER 70S.
LOWER 80S OVER THE WEST WITH LESS LAKE INFLUENCE AND WARMER TEMPS
ALOFT.
RIDGING ALOFT FIRMLY OVERHEAD ON MONDAY WITH GRADIENT S WIND BTWN
HIGH PRESSURE OVER LOWER GREAT LAKES AND NEW ENGLAND AND A LOW
PRESSURE TROUGH OVER THE NORTHERN PLAINS. H85 TEMPS VARY WILDLY
THOUGH WITH THE ECMWF PUSHING BULK OF WARMTH CLOSER TO THE SFC
TROUGH AND OVER NORTHERN ONTARIO /H85 TEMPS UP TO 15C OVER UPR
MICHIGAN/ WHILE GFS SHOWS H85 TEMPS PUSHING PAST 22C ACROSS UPR
MICHIGAN. BLEND OF GUIDANCE AND SYNOPTIC SETUP ALONE JUSTIFIES
CONSENSUS TEMPS TO AT LEAST LOWER 80S. NOT A LOT OF CHANGE FOR
FIRST DAY OF SEPTEMBER WITH LINGERING UPPER RIDGE AND APPROACHING
SFC FRONT. GFS BRINGS FRONT THROUGH UPPER LAKES QUICKER...BUT EXPECT
SLOWER IDEA FM ECMWF GIVEN THE UPPER RIDGE IT WILL BE RUNNING UP
AGAINST. DRY WEATHER AND WARMING TEMPS ALOFT AHEAD OF FRONT WITH
STRONGER S/SW WINDS WILL GIVE MOST AREAS AWAY FM LK MICHIGAN SHORE A
GOOD CHANCE OF SEEING HIGHS INTO MIDDLE OR POSSIBLY UPPER 80S. LOWER TO
MIDDLE 80S WITH ONLY SLIGHT CHANCE POPS WILL DO FOR NOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 121 AM EDT WED AUG 26 2015
A CONTINUED NW FLOW OF MOIST COOL AIR AROUND LOW PRES NE OF LAKE
SUPERIOR WILL ALLOW MVFR CONDITIONS TO PERSIST AT KIWD/KCMX/KSAW
THRU AT LEAST THE OVERNIGHT. EXPECT PATCHY -DZ AT KSAW INTO THE
MORNING HOURS...BUT SHOULDN`T REDUCE VIS BLO VFR. AS HIGH PRES
CONTINUES TO BUILD INTO THE AREA TODAY...MVFR CIGS WILL SCATTER OUT
AT KIWD/KCMX IN THE MORNING WHILE CLEARING WILL OCCUR LATER IN THE
AFTN AT KSAW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 411 PM EDT TUE AUG 25 2015
WITH LOW PRES NEAR JAMES BAY CONTINUING TO MOVE AWAY FROM THE AREA
AND HIGH PRES OVER THE PLAINS APPROACHING...WINDS WILL CONTINUE TO
DIMINISH ACROSS LAKE SUPERIOR FROM W TO E TONIGHT AND WED. WINDS
TONIGHT WILL GENERALLY RANGE FROM 10-20KT W TO 15-30KT E. WINDS ON
WED WILL DIMINISH TO UNDER 15KT W AND UNDER 20KT E BY THE END OF THE
AFTN. AS THE HIGH MOVES OVER THE UPPER LAKES WED NIGHT...WINDS WILL
BE UNDER 15KT ACROSS LAKE SUPERIOR. WINDS WILL BE MOSTLY UNDER 20KT
THU THRU SUN.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...VOSS
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS GLASGOW MT
858 PM MDT THU AUG 27 2015
.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH SATURDAY...
UPDATE...
FEW CHANGES WERE NEEDED TO THE INHERITED FORECAST. RADAR
OBSERVATIONS SUGGEST THAT A LONE SHOWER OVERNIGHT ACROSS SOUTHERN
AN EASTERN AREAS CANNOT BE COMPLETELY RULED OUT...SO POPS WERE
ADJUSTED ACCORDINGLY. OTHERWISE ALL IS ON TRACK. MALIAWCO
PREVIOUS DISCUSSION...
THE EMBEDDED SHORT-WAVE TROUGH WHICH RODE UP AND AROUND THE RIDGE
OF HIGH PRESSURE HAS NOW PASSED EAST OF MONTANA. ANY REMAINING
CHANCES FOR SHOWER AND THUNDERSTORM ACTIVITY THIS AFTERNOON AND
EVENING WILL BE MANIFESTED BY A RESIDUAL VERY SMALL-SCALE KINK IN
THE FLOW ALOFT APPROACHING FROM CENTRAL MONTANA AS THE UPPER-
LEVEL RIDGE NOW BEGINS TO RE-ASSERT ITSELF ACROSS THE REGION. EVEN
WITH THE TIME FRAME VERY NEAR...MODELS ARE STILL IN SIGNIFICANT
DISAGREEMENT AS TO HOW MUCH PRECIPITATION WILL FALL ACROSS NE
MONTANA THROUGH THIS EVENING. GFS AND HRRR ARE NEARLY COMPLETELY
DRY...THE NAM SHOWS A FEW SCATTERED AREAS OF LIGHT PRECIP...AND
THE EC CONTINUES TO HOLD ON TO A WIDE AREA OF WETTING RAIN ACROSS
THE WESTERN HALF OF OUR CWA. BY LATE TONIGHT...IT WILL BECOME
EVIDENT WHICH MODEL SOLUTION IS MORE TRUSTWORTHY IN THE NEAR SHORT
TERM.
REGARDLESS...EARLY FRIDAY MORNING THROUGH SATURDAY NIGHT SHOWS
MUCH BETTER MODEL CONSENSUS IN KEEPING NE MONTANA DRY AS A BONE
UNDER A DECENT RIDGE OF HIGH PRESSURE. INDEED...HIGH TEMPERATURES
FOR SATURDAY WILL EASILY REACH 100 DEGREES FOR MANY LOCATIONS. AT
THIS TIME...FIRE WEATHER CONCERNS WILL GENERALLY STILL BE HELD IN
CHECK AS SATURDAYS WIND SPEEDS MAY BE AROUND A BORDERLINE 15 MPH
WITH RH VALUES ALSO IN THE LOWER TEENS. WILL NEED TO KEEP A CLOSE
EYE ON THE POSSIBILITY FOR SLIGHTLY STRONGER WINDS AND/OR SLIGHTLY
DRIER RH VALUES...WHICH WOULD RAISE FIRE WEATHER CONCERNS.
LATER ON SATURDAY...THE FLOW ALOFT BEGINS TO TURN MORE FROM THE
SW...COURTESY OF THE LARGE PACNW TROUGH WHICH WILL PERSIST THROUGH
THE REMAINDER OF THE ENTIRE FORECAST WITH OFF AND ON CHANCES FOR
SHOWERS AND THUNDERSTORMS THROUGHOUT. BMICKELSON
.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY...
GOING FORECAST LOOKED GOOD. MODEL CONFIDENCE ON PRECIPITATION IS
LOW AS STRONG UNSTABLE SW JET STREAM INTERACTS WITH A DRY DESERT AIR
MASS. TFJ
PREVIOUS DISCUSSION...
HOT UPPER RIDGE OVER THE REGION EXPECTED TO BREAK DOWN OVER THE
WEEKEND AS THE UPPER LOW CURRENTLY IN THE EAST PACIFIC MOVES
ONSHORE. THIS TROF WILL BE REINFORCED BY WAVES DROPPING OUT OF
ALASKA...MAINTAINING THE TROF OVER WESTERN CANADA THROUGH NEXT
WEEK.
COLD FRONT SWEEPS ACROSS THE REGION SATURDAY NIGHT WITH THE BEST
CHANCE FOR SHOWERS OR THUNDERSTORMS FOLLOWING THE FRONT. AS THE
UPPER TROF MOVES ONSHORE...SOUTHWEST FLOW INTO EASTERN MONTANA
WILL KEEP TEMPERATURES NEAR NORMAL FOR THE REMAINDER OF THE WEEK.
SOME MOISTURE MAY WORK INTO THE REGION BUT NONE OF THE MEDIUM
RANGE MODELS INDICATE SIGNIFICANT UPPER ENERGY TO TRIGGER
PRECIPITATION. EBERT
&&
.AVIATION...
SYNOPSIS: RIDGING WILL CONTINUE OVER THE REGION THROUGH THE
PERIOD.
FLIGHT CATEGORY: VFR.
WIND AND WX: LIGHT WIND WILL GENERALLY SWITCH AROUND TO THE WEST
ON FRIDAY. THIS COULD BRING A REDUCTION TO VISIBILITY TO MVFR
LEVELS WITH SMOKE. PROTON
&&
.FIRE WEATHER...
NEXT FOCUS FOR FIRE WEATHER CONCERNS WILL BE SATURDAY AS THE
UPPER-LEVEL RIDGE OF HIGH PRESSURE WILL RE-ASSERT ITSELF OVER THE
REGION. A BREEZY TO SLIGHTLY GUSTY SOUTH WIND WILL SET UP.
SATURDAYS HIGH TEMPERATURES WILL CLIMB TO AROUND 100 DEGREES AND
THE LOWEST RH VALUES WILL BE SOMEWHERE IN THE LOW TO MID TEENS.
ONLY SLIGHT CHANGES IN THESE PARAMETERS WOULD RAISE FIRE WEATHER CONCERNS
FOR SATURDAY. WILL DEFER TO NEXT THE SHIFT AS SATURDAY IS STILL
DAY 3 OF THE FORECAST. BMICKELSON
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
343 PM CDT WED AUG 26 2015
.SYNOPSIS...
ISSUED AT 341 PM CDT WED AUG 26 2015
UPPER LEVEL RIDGE ACROSS THE ROCKIES...WITH A TROUGH ACROSS NEW
ENGLAND. SHORTWAVE MOVING ACROSS THE CREST OF THE RIDGE...CAUSING
THE RIDGE TO FLATTEN. ELONGATED SFC HIGH ACROSS MUCH OF THE MISS RVR
VALLEY. A STALLED BOUNDARY ANALYZED FROM A LOW OVER MONTANA...THEN
MEANDERS SE INTO CENTRAL KS. ALSO A DISTINCT DRY LINE ACROSS THE
PANHANDLE AND EASTERN COLORADO...WHERE DEW POINTS HAVE FALLEN INTO
THE 30S AND 40S WITH TEMPS NEAR/ABOVE 100.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 341 PM CDT WED AUG 26 2015
MAIN FOCUS WILL BE THUNDERSTORM CHANCES THE NEXT 24 HOURS. FIRST
WILL BE EARLY THIS EVENING ACROSS SOUTHWEST NEB...ALONG THE DRY
LINE. A COUPLE CU CLOUDS HAVE DEVELOPED...HOWEVER DEVELOPMENT IS
MINIMAL AND SHALLOW...SUGGESTING A CAP STILL IN PLACE. THE
NAM/GFS/EC KEEP THIS AREA QUIET...HOWEVER THE NEAR TERM RAP/HRRR IN
AGREEMENT A FEW ISOLD STORMS TO DEVELOP. THE RAP AND HRRR SUGGEST
STORMS SHOULD ALREADY BE DEVELOPED. HAVE A DRY FORECAST AT THE
MOMENT...THINKING THE NEAR TERM MODELS ARE SLIGHTLY OVERDONE WITH
MOISTURE AVAILABLE. THAT SAID...INVERTED V SOUNDING WEST OF THE DRY
LINE AND CAN NOT RULE OUT A STRAY STRONG STORM DEVELOPING. WILL
CONTINUE TO MONITOR.
NEXT FOCUS WILL BE FOLLOWING A COMBINATION OF A LEAD SHORTWAVE
RIDING THE CREST OF THE RIDGE ACROSS SOUTHERN S DAKOTA AND INTO
NORTHEASTERN NEB. THIS WILL COMBINE WITH LIFT FROM A NOCTURNAL LL
JET. MODELS IN GOOD AGREEMENT WITH THE NOSE NEAR THE NEB/S DAKOTA
BORDER. ANY ACTIVITY SHOULD DRIFT EAST THEN TURN TO THE SOUTHEAST.
THIS FOCUSES ACTIVITY ACROSS THE NORTHERN ZONES.
TOMORROW THE MAIN WAVE WILL CROSS THE AREA. MODELS HAVE SLOWED THE
SPEED FROM EARLIER RUNS. THIS WAVE HAS GOOD SUPPORT AND THE
DEEPENING MID LEVEL LOW WILL AID IN LIFT. MORNING CHANCES ARE
MINIMAL AS CAP IN PLACE...ALTHOUGH WILL HAVE TO MONITOR POSSIBLE
REMNANT OUTFLOW BOUNDARIES. OTHERWISE EXPECT EARLY AFTERNOON
DEVELOPMENT ACROSS THE WESTERN CWA WHICH WILL MOVE EAST. GOOD
INSTABILITY AND MARGINAL SHEAR SHOULD BE ENOUGH FROM SOME STRONG
STORMS. SHOULD SEE SOME MORE CLOUDS AND HIGHS HOLD IN THE 80S FOR
MOST LOCATIONS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 341 PM CDT WED AUG 26 2015
THE FRONT SWINGS THROUGH CENTRAL NEBRASKA THURSDAY NIGHT...BUT
MOISTURE WRAPPING AROUND THE UPPER LOW/TROUGH COULD STILL BRING THE
POSSIBILITY OF SHOWERS AND ISOLATED THUNDERSTORMS TO NORTH CENTRAL
NEBRASKA FRIDAY MORNING.
AFTER FRIDAY...LOW LEVEL FLOW WILL RETURN TO THE SOUTH AND BRING
WARMER TEMPERATURES TO CENTRAL AND WESTERN NEBRASKA THROUGH
SATURDAY. THE RETURN FLOW WILL ALSO BEGIN BRINGING MOISTURE TO THE
HIGH PLAINS FROM THE SOUTHWEST U.S. AND INCREASING THE LOW LEVEL
THETA-E. IN ADDITION...DESTABILIZATION IS LIKELY IN THE THETA-E
RIDGE. ANOTHER BOUNDARY COMING ACROSS THE STATE COULD BRING AT LEAST
A SLIGHT CHANCE OF THUNDERSTORMS TO WESTERN NEBRASKA NEBRASKA EARLY
NEXT WEEK. CURRENT INDICATIONS ARE THAT THE BEST MOISTURE WILL BE
OVER THE SOUTHEAST U.S. AS A TROPICAL SYSTEM INTERACTS WITH A WEAK
STATIONARY FRONT ACROSS THE GULF COAST STATES AND THE MOISTURE ON
THE HIGH PLAINS WILL BE LIMITED TO PRECIPITABLE WATER OF AN INCH OR
LESS. THIS WOULD ALSO LIMIT THE COVERAGE OF THE CONVECTION AND
PRETTY MUCH LIMIT IT TO THE NEBRASKA PANHANDLE AND WESTERN
SANDHILLS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1214 PM CDT WED AUG 26 2015
VFR CONDITIONS WILL CONTINUE ACROSS WESTERN AND NORTH CENTRAL
NEBRASKA THROUGH THURSDAY AFTERNOON. THE PRIMARY CONCERN THROUGH
WEDNESDAY EVENING IS THE WIND...WHICH WILL BE BREEZY AT TIMES OUT
OF THE SOUTH/SOUTHEAST. WEDNESDAY NIGHT...THERE IS A CHANCE OF
THUNDERSTORMS ACROSS NORTHERN NEBRASKA...INCLUDING KVTN. FELT
COVERAGE WILL LIKELY BE TOO LIMITED TO WARRANT TSRA IN THE CURRENT
FORECAST.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MASEK
SHORT TERM...MASEK
LONG TERM...SPRINGER
AVIATION...DS
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
502 AM EDT WED AUG 26 2015
.SYNOPSIS...
A WEAK COLD FRONT WILL SLOWLY MOVE OFF OF THE COAST TODAY AND
TONIGHT. THE FRONT WILL THEN LINGER JUST OFFSHORE INTO FRIDAY.
WEAK HIGH PRESSURE WILL BUILD INTO THE AREA FROM THE NORTH
THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 415 AM WEDNESDAY...SCATTERED SHOWERS AND THUNDERSTORMS
CONTINUE TO DEVELOP IN VICINITY OF THE SOUTHWARD DRIFTING COLD
FRONT WHICH APPEARED TO BE LOCATED ACROSS THE CRYSTAL COAST EARLY
THIS MORNING. THE FRONT MAY BRIEFLY PUSH BACK INLAND THIS
AFTERNOON WITH THE SEA BREEZE. GUIDANCE SEEMS TO BE SUGGESTING
THAT CURRENT SCATTERED ACTIVITY WILL DISSIPATE BY 15Z THEN THERE
WILL BE A LULL UNTIL AROUND 18Z WHEN ADDITIONAL SCATTERED SHOWERS
AND THUNDERSTORMS WILL DEVELOP WITH HEATING. MID LEVEL WINDS
INCREASE TO AROUND 30 KT WHICH COULD LEAD TO BETTER ORGANIZATION
OF DIURNAL CONVECTION, BUT LAPSE RATES WILL BE POOR LIMITING SEVERE
POTENTIAL ALTHOUGH GUSTY WINDS WILL BE POSSIBLE IN THE STRONGER
STORMS. THE MAIN THREAT CONTINUES TO BE LOCALLY HEAVY RAINS DUE TO
HIGH PW VALUES OF 1.5-2" AND THE POSSIBILITY OF TRAINING CELLS.
UPPER LEVEL DIVERGENCE WILL BE FAVORABLE FOR LIFT AS OUR REGION
WILL BE IN THE RIGHT ENTRANCE OF THE JET. USED A BLEND OF THE
MET/ECMWF MOS POPS AS THE GFS POPS LOOKED TOO LOW. IT WILL ONLY
TAKE A LITTLE SUNSHINE TO HELP BOOST TEMPS AND WILL FORECAST HIGHS
AROUND 90 INLAND AND MID TO UPPER 80S COAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
AS OF 415 AM WEDNESDAY...THE FRONT IS FORECAST TO COMPLETELY MOVE
OFF OF THE COAST LATE THEN STALL OFFSHORE OVERNIGHT. ALTHOUGH
COVERAGE OF PRECIPITATION IS EXPECTED TO DIMINISH WITH LOSS OF
HEATING THE AIRMASS WILL REMAIN MOIST AND EASTERN NC WILL REMAIN
IN A FAVORABLE QUAD OF THE UPPER JET PRODUCING LIFT. THUS WILL
NEED TO CONTINUE CHANCE POPS HIGHEST COAST NEAR THE DEPARTING
FRONT. LOWS WILL IN THE UPPER 60S INLAND AND AND MID 70S BEACHES.
THERE WILL BE A POTENTIAL FOR LOW CLOUDS AND FOG TO DEVELOP AS THE
LOW LEVEL FLOW BECOMES EASTERLY.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
AS OF 430 AM WEDNESDAY...THE UPPER TROUGH AXIS THAT HAS BEEN
ACROSS THE EASTERN CONUS WILL SHIFT EAST INTO NC THURSDAY WHILE
DE- AMPLIFYING THROUGH THURSDAY NIGHT. WEAK ZONAL FLOW DEVELOPS
FRIDAY WITH THE UPPER RIDGE OVER BERMUDA BUILDING WEST TOWARDS THE
SOUTHEASTERN STATES. AT THE SURFACE, A WEAK FRONT WILL REMAIN
STALL OFF THE NC COAST THROUGH FRIDAY.
LITTLE CHANGE IN FORECAST REASONING BASED ON 00Z GUIDANCE THROUGH
THE PERIOD. AN UPPER LEVEL JET CONTINUES ACROSS THE MID ATLANTIC
AND NEW ENGLAND COAST THROUGH THURSDAY WITH COASTAL AND OFFSHORE
AREAS OF EASTERN NC POSITIONED IN THE FAVORABLE RIGHT ENTRANCE
REGION OF THE JET. THE FRONTAL BOUNDARY AND DEEPEST MOISTURE
REMAINS STALLED OFFSHORE THROUGH THURSDAY NIGHT AND WILL MAINTAIN
SLIGHT CHANCE POPS INLAND TO HIGH CHANCE POPS FOR COASTAL
SECTIONS.
THE UPPER RIDGE ACROSS THE WESTERN ATLANTIC BUILDS WEST INTO THE
SOUTHEAST FRIDAY THROUGH EARLY NEXT WEEK WHILE A ROBUST NORTHERN
STREAM SHORTWAVE MOVES ACROSS THE MIDWEST INTO THE WEEKEND AND
LIFTS OVER THE RIDGE LATE IN THE WEEKEND AND EARLY NEXT WEEK.
AT THE SURFACE, HIGH PRESSURE WILL SHIFT OFF THE MID-ATLANTIC
COAST LATE FRIDAY AND RIDGE SOUTHWEST INTO EASTERN NC FRIDAY NIGHT
INTO SATURDAY, THEN TRANSITIONS OFFSHORE WITH THE PIEDMONT TROUGH
DEVELOPING SUNDAY THROUGH TUESDAY. SOME UNCERTAINTY IN THE TIMING
AND STRENGTH OF THE SHORTWAVE BUT IT APPEARS DEEPER MOISTURE AND
BETTER DYNAMICS WILL REMAIN JUST WEST AND NORTH OF EASTERN NC AND
WILL CONTINUE TO FORECAST A MORE TYPICAL DIURNALLY DRIVEN, MAINLY
ISOLATED SHOWER/THUNDERSTORM PATTERN THROUGH THE WEEKEND AND INTO
EARLY NEXT WEEK. TEMPERATURES WILL BE NEAR OR A FEW DEGREES
ABOVE CLIMATOLOGY FOR LATE AUGUST.
EYES WILL BE ON THE TROPICS THIS WEEKEND AS NHC HAS TS ERIKA
FORECAST TO MOVE INTO THE BAHAMAS BUT THERE IS A SIGNIFICANT
UNCERTAINTY IN THE STRENGTH AND TRACK OF THE SYSTEM BEYOND DAY 3
WITH POOR RUN TO RUN CONSISTENCY IN THE MODELS AND IT IS TOO SOON
TO SPECULATE AT THIS TIME WHAT IMPACTS MAY BE FELT ACROSS THE
REGION NEXT WEEK.
&&
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM /THROUGH TONIGHT/...
AS OF 115 AM WEDNESDAY...VERY DIFFICULT FORECAST TRYING TO
DETERMINE WHERE PREVAILING MVFR TO IFR CONDITIONS WILL PREVAIL
OVERNIGHT. DEWPOINTS ARE HIGHER THAN PREVIOUS FEW NIGHTS AND WINDS
HAVE AGAIN DECOUPLED. RADIATIONAL COOLING SET TO TAKE OFF BUT FOR
AREA OF LOWER CLOUDS STREAMING NORTHEAST ALONG A STALLED BOUNDARY
DRAPED SOUTHWEST TO NORTHEAST ACROSS EASTERN NC. WITH WET SOILS IN
AREAS THAT EARLIER RECEIVED RAIN THINK FOG POTENTIAL IS FAIRLY
GOOD BUT CLOUDS WILL LIKELY CONTINUE TO STREAM OVER THE AREA FOR
AT LEAST THE NEXT COUPLE OF HOURS INHIBITING FOG DEVELOPMENT. WILL
CONTINUE PREVIOUS FORECAST AND INTRODUCE PREVAILING IFR CIGS/VSBYS
7-9Z BASED ON AVIATION MOS AND HRRR AND NARRE AVIATION GUIDANCE.
IFR WILL IMPROVE TO VFR 12-14Z WEDNESDAY AS SURFACE BASED MOISTURE
MIXES OUT WITH SUB VFR CONDITIONS AGAIN EXPECTED IN VICINITY OF
SCATTERED SHOWERS AND THUNDERSTORMS.
LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 430 AM WEDNESDAY...A WEAK COLD FRONT WILL LINGER OFFSHORE
THURSDAY WITH COASTAL TERMINALS HAVING BETTER CHANCES OF BEING
IMPACTED BY SHRA/TSRA BRINGING REDUCED CIGS/VSBYS. PREDOMINANT VFR
CONDITIONS EXPECTED THURSDAY NIGHT THROUGH SUNDAY WITH ONLY
ISOLATED, MAINLY DIURNALLY DRIVEN SHRA/TSRA.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 415 AM WEDNESDAY...THE FRONT IS BEGINNING TO MOVE OFF OF
THE CRYSTAL COAST EARLY THIS MORNING BUT SHOULD RETREAT BACK TO
THE NORTH THIS AFTERNOON. THE FRONT IS THEN FORECAST TO MOVE
OFFSHORE AND STALL LATER TONIGHT. THROUGH THIS EVENING WINDS WILL
REMAIN LIGHT OUTSIDE OF CONVECTION /10 KT OR LESS/ WITH THE FLOW
BECOMING NORTHEAST TO EAST. AFTER MIDNIGHT TONIGHT WINDS ARE
FORECAST TO INCREASE TO 10 TO 15 KT AS HIGH PRESSURE BEGINS TO
BUILD INTO THE WATERS FROM THE NORTH. SEAS WILL BE IN THE 2 TO 4
FT RANGE MAINLY IN LONG PERIOD SWELL.
LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 430 AM WEDNESDAY...A WEAK COLD FRONT WILL LINGER OFFSHORE
THROUGH FRIDAY, PRODUCING NE WINDS 15 KT OR LESS THROUGH
THURSDAY GRADUALLY VEERING TO E THURSDAY NIGHT AND FRIDAY AS HIGH
PRESSURE BUILDS INTO THE MID-ATLANTIC REGION. THE HIGH WILL SHIFT
OFF THE MID-ATLANTIC COAST FRIDAY NIGHT INTO SATURDAY WITH
WINDS AROUND 10 KT OR LESS SATURDAY AND SUNDAY. WIND DIRECTION
WILL GENERALLY BE EAST TO SOUTHEAST BUT BECOMING VARIABLE AT TIMES
WITH WEAK GRADIENTS ACROSS THE REGION. SEAS WILL RANGE 1-3 FT
THROUGH THE LONG TERM WITH SOME 4 FT SEAS FOR THE OUTER CENTRAL
WATERS.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JME
NEAR TERM...JME
SHORT TERM...JME
LONG TERM...SK
AVIATION...JME/SK
MARINE...JME/SK
AREA FORECAST DISCUSSION
NWS RALEIGH NC
330 AM EDT WED AUG 26 2015
.SYNOPSIS...A STALLED FRONT WILL PERSIST IN VICINITY OF THE CAROLINA
COAST THROUGH THE DURATION OF THE WEEK.
&&
.NEAR TERM /OVERNIGHT/...
AS OF 935 PM TUESDAY...
00Z MESO-ANALYSIS DEPICTS A TONGUE OF MOISTURE AND INSTABILITY
ACROSS THE COASTAL PLAIN...AND INTO THE EASTERN SECTIONS OF THE
SANDHILLS. PRECIP WATER VALUES WERE AVERAGING 1.6-1.7 INCHES IN THIS
REGION. FARTHER WEST...PRECIP WATER VALUES AVERAGED 1.1 INCHES.
WATER VAPOR IMAGERY SUGGESTED A SHEAR AXIS EDGING SLOWLY EAST ACROSS
EASTERN NC. THIS FEATURE INTERACTING WITH AVAILABLE MOISTURE AND
MODEST INSTABILITY WAS TRIGGERING A FEW SHOWERS ALONG AND EAST OF
HIGHWAY 1...MAINLY IN VICINITY OF WILSON...AND OVER SECTIONS OF THE
WESTERN SANDHILLS. LATEST RUC MODEL SUGGEST A VORT MAX AND ATTENDANT
SHEAR AXIS DRIFTING EAST ALONG THE SC-NC BORDER THROUGH THE PRE-DAWN
HOURS.
BASED ON HOW WELL ISOLATED-SCATTERED CONVECTION HAS MAINTAINED
ITSELF THROUGH MID EVENING AND NEAR TERN MODELS SUGGESTING A THREAT
LASTING WELL INTO THE NIGHT...WILL MAINTAIN A SLIGHT-SMALL CHANCE
POP...GENERALLY ALONG AND EAST OF I-95 THROUGH THE PRE-DAWN HOURS.
ANOTHER SHEAR AXIS NOTED CROSSING THE TN-LOWER OH VALLEY THIS
EVENING...APPROACHING THE SOUTHERN-CENTRAL APPALACHIANS. WHILE
MOISTURE IS MORE LIMITED OVER WESTERN NC...THIS FEATURE MAY ENHANCE
CLOUDINESS A BIT AND POSSIBLY TRIGGER A SPRINKLE OR TWO OVERNIGHT IN
VICINITY OF THE TRIAD.
IN ANTICIPATION OF MORE CLOUDINESS...HAVE RAISED MIN TEMPS ABOUT TWO
DEGREES IN SOME SPOTS...ESPECIALLY IN THE NW PIEDMONT. MIN TEMPS
SHOULD VARY FROM THE MID 60S NW TO AROUND 70 SE.
&&
.SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/...
AS OF 100 PM TUESDAY...
LITTLE CHANGE IN THE OVERALL PATTERN IS EXPECTED ON WED...WITH THE
UNSEASONABLY STRONG UPPER LEVEL LOW STALLED NORTH OF THE GREAT
LAKES...CYCLONIC FLOW ALOFT ALONG THE EASTERN SEABOARD...AND A
STALLED FRONTAL ZONE IN VICINITY OF THE CAROLINA/SOUTHEAST COAST. AS
A RESULT...EXPECT CONDITIONS ON WED TO BE SIMILAR TO TODAY...WITH
THE BEST POTENTIAL FOR CONVECTION IN COASTAL/FAR-EASTERN NORTH
CAROLINA. WILL KEEP PRECIP CHANCES GENERALLY CONFINED TO THE FAR SE
COASTAL PLAIN COUNTIES (I.E. CUMBERLAND/SAMPSON/WAYNE). ADDITIONAL
SHORTWAVE ENERGY DIGGING SOUTHEAST ALONG THE WESTERN PERIPHERY OF
THE STALLED UPPER LOW IS PROGGED TO PROGRESS INTO THE CENTRAL
APPALACHIANS LATE WED NIGHT...AND IT IS POSSIBLE THAT THE FRONTAL
ZONE SHIFTS FURTHER INLAND (ALONG WITH A POTENTIAL FOR PRECIP) AFTER
MIDNIGHT AS LOW-LEVEL WIND/HEIGHT FIELDS RESPOND TO THE APPROACHING
SHORTWAVE. FORECAST CONFIDENCE REMAINS LOW WITH REGARD TO THE
EVOLUTION/TIMING OF THE APPROACHING WAVE...THE STALLED FRONTAL
ZONE...AND WHETHER AN INLAND SHIFT IN PRECIPITATION WILL OCCUR (AS
THE GFS SUGGESTS) OR PRECIPITATION REMAINS ALONG THE COAST (AS THE
NAM SUGGESTS). -VINCENT
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 300 AM WEDNESDAY...
IN THE WAKE OF THE EASTERN US TROUGH LIFTING NEWD INTO EASTERN
CANADA...WEAK TROUGHINESS WILL EXTEND FROM THE CENTRAL GULF
NORTHWARD INTO THE LOWER MS VALLEY AS THE SUBTROPICAL RIDGE OVER THE
WESTERN ATLANTIC RETROGRADES TOWARDS THE SOUTHEAST COAST. MEANWHILE
AT THE SURFACE...WEAK SURFACE HIGH WILL SLIDE EASTWARD OVER THE MID-
ATLANTIC STATES...WHICH SHOULD NUDGE THE LINGERING SURFACE FRONTAL
BOUNDARY EVER SO SLIGHTLY SOUTHEASTWARD...REMAINING NEAR THE
SOUTHEAST COAST THROUGH THE WEEKEND.
UNDER INCREASING HEIGHTS ALOFT AND WEAK SFC HIGH PRESSURE...FRIDAY
AND SATURDAY LOOKS MOSTLY DRY ACROSS CENTRAL NC WITH RAIN CHANCES
MAINLY CONFINED TO THE DIFFERENTIAL HEATING OVER MTNS AND FTHLS AND
ALONG THE IMMEDIATE COAST INVOF OF THE LINGERING SFC BOUNDARY. BY
SUNDAY...SHOWERS AND STORMS COULD RETURN TO THE AREA...ESPECIALLY
ACROSS WESTERN PORTION S OF THE STATE WHERE THE APPROACH OF
MID/UPPER LEVEL SHORTWAVE TROUGH OVER THE UPPER MS VALLEY/LOWER
GREAT LAKES COULD KICK THE LINGERING WEAK TROUGHINESS OVER LOWER MS
VALLEY EASTWARD INTO THE AREA. SEASONABLE TEMPERATURES WITH HIGHS IN
THE MID TO UPPER 80S. LOWS 65 TO 70.
FORECAST CONFIDENCE DECREASES BY EARLY NEXT WEEK DUE TO UNCERTAINTY
OF HOW MUCH SUBTROPICAL RIDGING EXISTS OVER THE SOUTHEAST...WHICH
WILL GREATLY DETERMINE THE EVOLUTION TRACK OF TC ERICKA.
REGARDLESS...HEIGHTS WILL INCREASE EARLY NEXT WEEK AND SHOULD SEE AN
UPTICK IN TEMPS...UPPER 80S TO LOWER 90S MONDAY AND TUESDAY...WITH
AT LEAST WIDELY SCATTERED DIURNAL CONVECTION IN THE MOIST AIRMASS.
STAY TUNED.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 200 AM WEDNESDAY...
24 HOUR TAF PERIOD: ALL THE SENSIBLE WEATHER IN THE TAF PERIOD WILL
MOST LIKELY OCCUR IN THE EASTERN HALF OF THE AREA WITH KFAY AND KRWI
BEING THE PRIMARY TERMINALS AFFECTED. AS FAR AS CONVECTION IS
CONCERNED...THERE ARE CURRENTLY SHOWERS AND THUNDERSTORMS IN THE
VICINITY OF KFAY AND THESE ARE EXPECTED TO CONTINUE FOR THE NEXT
SEVERAL HOURS BUT WEAKEN OVER TIME. OF SECONDARY CONCERN WILL BE
AREAS OF FOG THIS EVENING...PARTICULARLY AT KRWI AND KFAY. TO THIS
POINT...ANY OBSERVATIONS OF VISIBILITY RESTRICTIONS HAVE BEEN IN THE
MVFR RANGE AND THIS IS EXPECTED TO BE THE PRIMARY CATEGORY FOR THE
EVENING WITH AN OUTSIDE CHANCE OF SOME IFR CONDITIONS...ESPECIALLY
AFTER THE RAIN AT KFAY. LATER IN THE DAY EXPECT ANOTHER ROUND OF
CONVECTION IN THE EAST...WITH KRWI AND KFAY ONCE AGAIN THE MOST
LIKELY AFFECTED HOWEVER IT IS POSSIBLE THAT SHORTWAVE ENERGY WILL
HELP SOME ISOLATED SHOWER ACTIVITY FURTHER WEST IN THE VICINITY OF
KRDU NEAR THE END OF THE TAF PERIOD.
LONG TERM: WITH THE FRONTAL ZONE STALLING OUT OVER THE EASTERN HALF
OF THE STATE...TERMINALS ALONG AND EAST OF ROUTE 1 WILL BE UNDER
CONTINUED THREAT FOR DAILY SHOWERS AND THUNDERSTORMS...PARTICULARLY
DURING AFTERNOON PEAK HEATING. TRIAD TERMINALS SHOULD REMAIN LARGELY
VFR FOR MUCH OF THE WEEK BUT UNCERTAINTY INCREASES TOWARDS THE
WEEKEND WHEN THE FRONTAL ZONE COULD RETROGRADE A LITTLE AS A WEAK
LOW FORMS SOUTH OF THE AREA.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...WSS
SHORT TERM...VINCENT
LONG TERM...CBL
AVIATION...ELLIS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
203 AM EDT WED AUG 26 2015
.SYNOPSIS...A STALLED FRONT WILL PERSIST IN VICINITY OF THE CAROLINA
COAST THROUGH THE DURATION OF THE WEEK.
&&
.NEAR TERM /OVERNIGHT/...
AS OF 935 PM TUESDAY...
00Z MESO-ANALYSIS DEPICTS A TONGUE OF MOISTURE AND INSTABILITY
ACROSS THE COASTAL PLAIN...AND INTO THE EASTERN SECTIONS OF THE
SANDHILLS. PRECIP WATER VALUES WERE AVERAGING 1.6-1.7 INCHES IN THIS
REGION. FARTHER WEST...PRECIP WATER VALUES AVERAGED 1.1 INCHES.
WATER VAPOR IMAGERY SUGGESTED A SHEAR AXIS EDGING SLOWLY EAST ACROSS
EASTERN NC. THIS FEATURE INTERACTING WITH AVAILABLE MOISTURE AND
MODEST INSTABILITY WAS TRIGGERING A FEW SHOWERS ALONG AND EAST OF
HIGHWAY 1...MAINLY IN VICINITY OF WILSON...AND OVER SECTIONS OF THE
WESTERN SANDHILLS. LATEST RUC MODEL SUGGEST A VORT MAX AND ATTENDANT
SHEAR AXIS DRIFTING EAST ALONG THE SC-NC BORDER THROUGH THE PRE-DAWN
HOURS.
BASED ON HOW WELL ISOLATED-SCATTERED CONVECTION HAS MAINTAINED
ITSELF THROUGH MID EVENING AND NEAR TERN MODELS SUGGESTING A THREAT
LASTING WELL INTO THE NIGHT...WILL MAINTAIN A SLIGHT-SMALL CHANCE
POP...GENERALLY ALONG AND EAST OF I-95 THROUGH THE PRE-DAWN HOURS.
ANOTHER SHEAR AXIS NOTED CROSSING THE TN-LOWER OH VALLEY THIS
EVENING...APPROACHING THE SOUTHERN-CENTRAL APPALACHIANS. WHILE
MOISTURE IS MORE LIMITED OVER WESTERN NC...THIS FEATURE MAY ENHANCE
CLOUDINESS A BIT AND POSSIBLY TRIGGER A SPRINKLE OR TWO OVERNIGHT IN
VICINITY OF THE TRIAD.
IN ANTICIPATION OF MORE CLOUDINESS...HAVE RAISED MIN TEMPS ABOUT TWO
DEGREES IN SOME SPOTS...ESPECIALLY IN THE NW PIEDMONT. MIN TEMPS
SHOULD VARY FROM THE MID 60S NW TO AROUND 70 SE.
&&
.SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/...
AS OF 100 PM TUESDAY...
LITTLE CHANGE IN THE OVERALL PATTERN IS EXPECTED ON WED...WITH THE
UNSEASONABLY STRONG UPPER LEVEL LOW STALLED NORTH OF THE GREAT
LAKES...CYCLONIC FLOW ALOFT ALONG THE EASTERN SEABOARD...AND A
STALLED FRONTAL ZONE IN VICINITY OF THE CAROLINA/SOUTHEAST COAST. AS
A RESULT...EXPECT CONDITIONS ON WED TO BE SIMILAR TO TODAY...WITH
THE BEST POTENTIAL FOR CONVECTION IN COASTAL/FAR-EASTERN NORTH
CAROLINA. WILL KEEP PRECIP CHANCES GENERALLY CONFINED TO THE FAR SE
COASTAL PLAIN COUNTIES (I.E. CUMBERLAND/SAMPSON/WAYNE). ADDITIONAL
SHORTWAVE ENERGY DIGGING SOUTHEAST ALONG THE WESTERN PERIPHERY OF
THE STALLED UPPER LOW IS PROGGED TO PROGRESS INTO THE CENTRAL
APPALACHIANS LATE WED NIGHT...AND IT IS POSSIBLE THAT THE FRONTAL
ZONE SHIFTS FURTHER INLAND (ALONG WITH A POTENTIAL FOR PRECIP) AFTER
MIDNIGHT AS LOW-LEVEL WIND/HEIGHT FIELDS RESPOND TO THE APPROACHING
SHORTWAVE. FORECAST CONFIDENCE REMAINS LOW WITH REGARD TO THE
EVOLUTION/TIMING OF THE APPROACHING WAVE...THE STALLED FRONTAL
ZONE...AND WHETHER AN INLAND SHIFT IN PRECIPITATION WILL OCCUR (AS
THE GFS SUGGESTS) OR PRECIPITATION REMAINS ALONG THE COAST (AS THE
NAM SUGGESTS). -VINCENT
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
AS OF 115 PM TUESDAY...
FRONTAL ZONE REMAINS PINNED ALONG THE NC COAST AS MILD HIGH PRESSURE
BUILDS ACROSS THE GREAT LAKES AND SOUTH DOWN THE EASTERN SPINE OF
THE APPALACHIANS INTO THE WEEKEND. MEANWHILE...ALOFT...THE FRONTAL
ZONE LIES BETWEEN A WEAK UPPER TROF OVER THE ATLANTIC COAST AND
STRONGER OFFSHORE RIDGE WHICH WILL BEGIN TO RETROGRADE INTO THE
SOUTHEAST ATLANTIC COAST...PROVIDING ADDITIONAL MOISTURE AS WELL AS
NUDGING THE FRONT SLOWLY INLAND. WILL KEEP THE CHANCE OF RAIN ONLY
MARGINALLY ABOVE CLIMATOLOGICAL...~30%...AND FOCUSED PRIMARILY ON
THE SOUTHEAST THROUGH SATURDAY. CLOUDINESS WILL BECOME MORE
PREVALENT ON SATURDAY AS OVERRUNNING EASTERLY FLOW SETS UP...WHICH
COULD LEAD TO INCREASING POPS AS THE WEEKEND APPROACHES. HIGHS EACH
DAY WILL BE PRETTY NEAR CLIMATOLOGICAL...POTENTIALLY COOLER ON
SATURDAY...POSSIBLY SUNDAY AS WELL...IF THE DAMMING AND PRECIP
SCENARIO MATERIALIZES.
UNCERTAINTY INCREASES BY EARLY NEXT WEEK AS WE WILL POTENTIALLY BE
SUBJECT TO THE INFLUENCE OF TS ERIKA. WE WILL BE IN THE WEAK TROF
AREA BETWEEN AN AMPLIFYING RIDGE IN THE MIDWEST AND THE STRONGER AND
STILL RETROGRADING SUBTROPICAL RIDGE OVER THE SOUTHWEST
ATLANTIC...WHICH SHOULD BE THE DETERMINING STEERING MECHANISM FOR
ERIKA OR HER REMAINS. REGARDLESS...HEIGHTS WILL INCREASE EARLY NEXT
WEEK AND SHOULD SEE AN UPTICK IN TEMPS...UPPER 80S TO LOWER 90S
MONDAY AND TUESDAY...WITH AT LEAST WIDELY SCATTERED DIURNAL
CONVECTION IN THE MOIST AIRMASS. STAY TUNED.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 200 AM WEDNESDAY...
24 HOUR TAF PERIOD: ALL THE SENSIBLE WEATHER IN THE TAF PERIOD WILL
MOST LIKELY OCCUR IN THE EASTERN HALF OF THE AREA WITH KFAY AND KRWI
BEING THE PRIMARY TERMINALS AFFECTED. AS FAR AS CONVECTION IS
CONCERNED...THERE ARE CURRENTLY SHOWERS AND THUNDERSTORMS IN THE
VICINITY OF KFAY AND THESE ARE EXPECTED TO CONTINUE FOR THE NEXT
SEVERAL HOURS BUT WEAKEN OVER TIME. OF SECONDARY CONCERN WILL BE
AREAS OF FOG THIS EVENING...PARTICULARLY AT KRWI AND KFAY. TO THIS
POINT...ANY OBSERVATIONS OF VISIBILITY RESTRICTIONS HAVE BEEN IN THE
MVFR RANGE AND THIS IS EXPECTED TO BE THE PRIMARY CATEGORY FOR THE
EVENING WITH AN OUTSIDE CHANCE OF SOME IFR CONDITIONS...ESPECIALLY
AFTER THE RAIN AT KFAY. LATER IN THE DAY EXPECT ANOTHER ROUND OF
CONVECTION IN THE EAST...WITH KRWI AND KFAY ONCE AGAIN THE MOST
LIKELY AFFECTED HOWEVER IT IS POSSIBLE THAT SHORTWAVE ENERGY WILL
HELP SOME ISOLATED SHOWER ACTIVITY FURTHER WEST IN THE VICINITY OF
KRDU NEAR THE END OF THE TAF PERIOD.
LONG TERM: WITH THE FRONTAL ZONE STALLING OUT OVER THE EASTERN HALF
OF THE STATE...TERMINALS ALONG AND EAST OF ROUTE 1 WILL BE UNDER
CONTINUED THREAT FOR DAILY SHOWERS AND THUNDERSTORMS...PARTICULARLY
DURING AFTERNOON PEAK HEATING. TRIAD TERMINALS SHOULD REMAIN LARGELY
VFR FOR MUCH OF THE WEEK BUT UNCERTAINTY INCREASES TOWARDS THE
WEEKEND WHEN THE FRONTAL ZONE COULD RETROGRADE A LITTLE AS A WEAK
LOW FORMS SOUTH OF THE AREA.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...WSS
SHORT TERM...VINCENT
LONG TERM...MLM
AVIATION...ELLIS
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
118 AM EDT WED AUG 26 2015
.SYNOPSIS...
A WEAK COLD FRONT WILL STALL OVER THE AREA TONIGHT AND WEDNESDAY.
THE FRONT WILL THEN SLOWLY MOVE OFF THE COAST WEDNESDAY NIGHT AND
THURSDAY BUT LINGER JUST OFFSHORE INTO FRIDAY. WEAK HIGH PRESSURE
WILL BUILD INTO THE AREA FROM THE NORTH THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 115 AM WEDNESDAY...VERY WEAK GRADIENT CONTINUES ACROSS
EASTERN NC AND THIS HAS LED TO WINDS DECOUPLING ACROSS MOST OF THE
AREA. THIS MAKES TRYING TO LOCATE THE WEAK FRONT/WIND SHIFT VERY
DIFFICULT LATE TONIGHT. BEST GUESS PLACES THE NEARLY STATIONARY
BOUNDARY ACROSS NE SECTIONS OF NC EXTENDING BACK SW ACROSS THE
COASTAL PLAIN. A FEW SHOWERS AND THUNDERSTORMS LINGER NEAR THE
BOUNDARY VICINITY OF THE SAND HILLS WITH ISOLATED SHOWERS
CURRENTLY DEVELOPING COASTAL DARE AND HYDE COUNTIES. WILL NEED TO
CONTINUE LOW CHANCE POPS OVERNIGHT GIVEN THE LINGERING SFC FRONT
AND MOIST BOUNDARY LAYER AMID CYCLONIC FLOW ALOFT. PATCHY FOG
LIKELY OVERNIGHT ESPECIALLY IN AREAS THAT RECEIVED RAIN TODAY. MIN
TEMPS FROM UPR 60S INLAND TO LOW-MID 70S COAST.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 AM THURSDAY/...
AS OF 330 PM TUESDAY...STALLED FRONT AND WEAK SHRT WV ENERGY
PATTERN WILL PERSIST THROUGH WED...WITH MODELS INDICATING SCT
SHOWERS/TSTMS WITH LOCALLY HEAVY RAIN PSBL MOST OF DAY BUT MAINLY
IN SEA BREEZE ZONE DURING AFTN. MAX TEMPS MID TO UPR 80S.
&&
.LONG TERM /THURSDAY THROUGH WEDNESDAY/...
AS OF 255 PM TUESDAY...AN UPPER LOW NORTH OF THE GREAT LAKES WILL
PUSH EAST ACROSS QUEBEC WEDNESDAY INTO THURSDAY, ALLOWING THE
UPPER TROUGH AXIS TO SHIFT EAST INTO NC BY THURSDAY THEN DE-
AMPLIFYING AS IT CROSSES THE CAROLINAS INTO THURSDAY NIGHT. WEAK
ZONAL FLOW DEVELOPS FRIDAY WITH THE UPPER RIDGE OVER BERMUDA
BUILDING WEST TOWARDS THE SOUTHEASTERN STATES. AT THE SURFACE, A
WEAK FRONT ACROSS EASTERN NC WILL MOVE OFF THE COAST AND STALL
WEDNESDAY NIGHT THROUGH FRIDAY.
LITTLE CHANGE IN FORECAST REASONING BASED ON 12Z GUIDANCE THROUGH
THE PERIOD. UPPER LEVEL JET STRENGTHENS ACROSS THE MID ATLANTIC
AND NEW ENGLAND COAST WEDNESDAY NIGHT THROUGH THURSDAY WITH
COASTAL AND OFFSHORE AREAS OF EASTERN NC POSITIONED IN THE
FAVORABLE RIGHT ENTRANCE REGION OF THE JET. THE FRONTAL BOUNDARY
AND DEEPEST MOISTURE REMAINS STALLED OFFSHORE THROUGH THURSDAY
NIGHT AND WILL MAINTAIN SLIGHT CHANCE POPS INLAND TO HIGH CHANCE
POPS FOR COASTAL SECTIONS.
THE UPPER TROUGH LIFTS NORTH OF THE REGION THURSDAY NIGHT WITH THE
UPPER RIDGE ACROSS THE WESTERN ATLANTIC BUILDING WEST INTO THE
SOUTHEAST FRIDAY THROUGH EARLY NEXT WEEK. MEANWHILE, SURFACE HIGH
PRESSURE WILL SHIFT OFF THE MID-ATLANTIC COAST LATE FRIDAY AND
RIDGE SOUTHWEST INTO EASTERN NC FRIDAY NIGHT INTO SATURDAY, THEN
TRANSITIONS OFFSHORE WITH THE PIEDMONT TROUGH DEVELOPING SUNDAY
THROUGH TUESDAY. EXPECT A MORE TYPICAL DIURNALLY DRIVEN, MAINLY
ISOLATED SHOWER/THUNDERSTORM PATTERN THROUGH THE WEEKEND AND INTO
EARLY NEXT WEEK. TEMPERATURES WILL BE NEAR OR A FEW DEGREES ABOVE
CLIMATOLOGY FOR LATE AUGUST.
&&
.AVIATION /05Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM /THROUGH WEDNESDAY NIGHT/...
AS OF 115 AM WEDNESDAY...VERY DIFFICULT FORECAST TRYING TO
DETERMINE WHERE PREVAILING MVFR TO IFR CONDITIONS WILL PREVAIL
OVERNIGHT. DEWPOINTS ARE HIGHER THAN PREVIOUS FEW NIGHTS AND WINDS
HAVE AGAIN DECOUPLED. RADIATIONAL COOLING SET TO TAKE OFF BUT FOR
AREA OF LOWER CLOUDS STREAMING NORTHEAST ALONG A STALLED BOUNDARY
DRAPED SOUTHWEST TO NORTHEAST ACROSS EASTERN NC. WITH WET SOILS IN
AREAS THAT EARLIER RECEIVED RAIN THINK FOG POTENTIAL IS FAIRLY
GOOD BUT CLOUDS WILL LIKELY CONTINUE TO STREAM OVER THE AREA FOR
AT LEAST THE NEXT COUPLE OF HOURS INHIBITING FOG DEVELOPMENT. WILL
CONTINUE PREVIOUS FORECAST AND INTRODUCE PREVAILING IFR
CIGS/VSBYS 7-9Z BASED ON AVIATION MOS AND HRRR AND NARRE AVIATIONGUIDANCE.
IFR WILL IMPROVE TO VFR 12-14Z WEDNESDAY AS SURFACE BASED MOISTURE
MIXES OUT WITH SUB VFR CONDITIONS AGAIN EXPECTED IN VICINITY OF
SCATTERED SHOWERS AND THUNDERSTORMS.
LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 245 PM TUESDAY...A WEAK COLD FRONT WILL LINGER OFFSHORE
WEDNESDAY NIGHT AND THURSDAY WITH COASTAL TERMINALS HAVING BETTER
CHANCES OF BEING IMPACTED BY SHRA/TSRA BRINGING REDUCED CIGS/VSBYS.
PREDOMINANT VFR CONDITIONS EXPECTED THURSDAY NIGHT THROUGH
SATURDAY WITH ONLY ISOLATED, MAINLY DIURNALLY DRIVEN SHRA/TSRA.
&&
.MARINE...
SHORT TERM /THROUGH WEDNESDAY/...
AS OF 115 AM WEDNESDAY...STALLED SFC FRONT INLAND TONIGHT WILL
CONTRIBUTE TO A WEAK PRES GRADIENT RESULTING IN SOUTHERLY WINDS
10 KT OR LESS ACROSS THE MARINE AREA THROUGH PERIOD. WW3 AND NWPS
IN GOOD AGREEMENT WITH LONG PERIOD SEAS PERSISTING AT 2-3 FT.
LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 250 PM TUESDAY...A WEAK COLD FRONT WILL LINGER OFFSHORE
THROUGH FRIDAY, PRODUCING NE WINDS 10 KT OR LESS THROUGH THURSDAY.
E/NE WINDS INCREASE SOME FRIDAY INTO FRIDAY EVENING, AROUND 10 TO
15 KT, AS GRADIENT TIGHTENS DUE TO HIGH PRESSURE BUILDING INTO
THE MID-ATLANTIC REGION. THE HIGH WILL SHIFT OFF THE MID-ATLANTIC
COAST FRIDAY NIGHT INTO SATURDAY WITH WINDS BECOMING PREDOMINANTLY
EASTERLY AROUND 10 KT OR LESS SATURDAY AND SUNDAY, SHIFTING
SOUTHEASTERLY LATE SUNDAY. SEAS WILL RANGE 1-3 FT THROUGH THE
LONG TERM WITH SOME 4 FT SEAS FOR THE OUTER CENTRAL WATERS FRIDAY
THROUGH SUNDAY.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JBM
NEAR TERM...JME/BTC
SHORT TERM...JBM
LONG TERM...DAG
AVIATION...JME/DAG
MARINE...JME/BTC/JBM/DAG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
338 PM CDT WED AUG 26 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 332 PM CDT WED AUG 26 2015
500 MB UPPER RIDGE BUILDING FROM NEW MEXICO INTO ERN WYOMING.
SEVERAL SHORT WAVES SEEN MOVING ON TOP OF UPPER RIDGE INTO
WRN/CNTRL ND AND SOUTH DAKOTA TODAY. SOME BANDS OF MID AND HIGH
LEVEL CLOUD COVER WITH THESE WAVES AND NOT SURE IF MODELS ARE
HANDLING THESE CLOUDS BANDS ALL THAT GOOD. ONE CLOUD BAND NORTH OF
WILLISTON TO RUGBY MOVING EAST-SOUTHEAST AND THE OTHER SOUTH OF
WATFORD CITY TO BISMARCK MOVING SOUTHEAST. THE NRN CLOUD BAND ISNT
HANDLED BY THE MODELS WELL AT ALL AS THEY WANT TO DRY UP THE
CLOUDS TOO MUCH IT SEEMS. OTHER CLOUD BAND HANDLED OK BY HRRR IN
HAVING A FEW SPRINKLES INTO SCNTRL ND EARLY EVENING. LATEST HRRR
HAS A FEW RW-- INTO FAR SE ND AS WELL OVERNIGHT. WILL MAINTAIN DRY
FCST AND LATER SHIFTS CAN ADD RW-- HAS NEEDED. IT WOULD BE VERY
VERY MINOR.
WARMER THAN THE LAST FEW NIGHTS AS SOUTHERLY WINDS HOLD UP ENOUGH
FOR MORE MIXING.
MAIN SHORT WAVE WILL MOVE EAST AND TEMPORARILY SQUASH THE RIDGE
AND MOVE THRU SRN SD INTO SRN MN/NRN IA LATER THURSDAY AFTERNOON
AND NIGHT. NRN EDGE OF ANY PRECIP WILL JUST SKIRT THE FAR SRN FCST
AREA SO CONFINED POPS TO THAT AREA ONLY. A FEW DEGREES WARMER ON
THURSDAY AS WELL.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 332 PM CDT WED AUG 26 2015
A SHORT WAVE MOVING EAST THRU SRN CANADA WILL BRING A RISK OF A
T-STORM TO THE CANADIAN BORDER REGION FRI AFTN-EVE.. BIT BETTER
RISK IN LAKE OF THE WOODS AREA FRI EVE. OTHERWISE GETTING WARMER
STILL AS UPPER AIR RIDGE BEINGS TO BUILD NORTHWARD. UPPER AIR
BUILDS INTO NORTH DAKOTA SATURDAY AS HIGH TEMPS CLIMB WELL INTO
THE 80S. IT WILL BE DRY.
SATURDAY NIGHT-WEDNESDAY...A VERY WARM AND FAIRLY QUIET PERIOD IS
EXPECTED. A WEST TO SOUTHWEST FLOW PATTERN ALOFT WILL PERSIST OVER
THE N PLAINS WITH THE MEAN UPPER RIDGE OVER THE EASTERN CONUS AND
PERSISTENT TROUGHING OVER THE PACIFIC NORTHWEST. WITH THE UPPER JET
REMAINING NORTH INTO CANADA...ORGANIZED PRECIP CHANCES LOOK LOW.
SOME UPPER LEVEL ENERGY WILL SLIDE NORTH ACROSS CENTRAL CANADA EARLY
IN THE WEEK...POSSIBLY DRAGGING A SFC TROUGH INTO THE AREA WITH
MAYBE A FEW STORMS. OTHERWISE...ANY OTHER STORMS WILL DEPEND ON
SUBTLE FORCING WITH WEAK UPPER WAVES. TEMPS WILL REMAIN ABOVE
AVERAGE...WITH HIGHS GENERALLY IN THE 80S TO PERHAPS LOW 90S IN
SPOTS...AND LOWS IN THE 60S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1257 PM CDT WED AUG 26 2015
VFR CONDITIONS EXPECTED THROUGH THE PERIOD WITH
GENERALLY SOUTHERLY FLOW UP TO AROUND 10 KTS (POSSIBLY LIGHT AND
VARIABLE IN SPOTS EARLY THURSDAY) AND PATCHES OF MID/HIGH
CLOUDS.|
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...RIDDLE
LONG TERM...MAKOWSKI/RIDDLE
AVIATION...MAKOWSKI
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1134 PM CDT TUE AUG 25 2015
.UPDATE...
ISSUED AT 1134 PM CDT TUE AUG 25 2015
NO CHANGES FOR THIS UPDATE.
UPDATE ISSUED AT 944 PM CDT TUE AUG 25 2015
RAP AND HRRR HAVE STARTED TO DEVELOP SOME LOW VIS FROM THE
NORTHERN RED RIVER VALLEY EASTWARD. DEW POINTS IN THAT AREA HAVE
BEEN COMING UP AS THE BOUNDARY LAYER DECOUPLES...AND THERE HAS
BEEN A DROP TO 7 MILES VIS AT LANGDON. THINK SOME
VERY PATCHY SHALLOW FOG WILL BE POSSIBLE PARTICULARLY OVER PLACES
THAT HAVE RECENT RAINFALL. DO NOT THINK IT WILL LAST
LONG WITH THE SFC HIGH MOVING EAST...BUT THREW IN A BRIEF MENTION
OF PATCHY FOG IN THE NORTHERN VALLEY SHORTLY AFTER 07Z AND
TRANSITIONING OVER INTO NORTHWEST MN TOWARDS MORNING.
UPDATE ISSUED AT 634 PM CDT TUE AUG 25 2015
NO CHANGES TO THE GOING FORECAST. SOME SMOKE FROM FIRES TO OUR
NORTHWEST BEGINNING TO MOVE INTO THE WESTERN COUNTIES.
HOWEVER...IT IS ALL HIGH LEVEL AT THIS POINT AND WILL HOLD OFF ON
ANY INCLUSION IN THE GRIDS UNTIL IT CAUSES REDUCTION IN VIS AT THE
SFC.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 312 PM CDT TUE AUG 25 2015
MAIN FORECAST CHALLENGE WILL BE TEMPS...UNTIL THE NEXT CHANCE OF
PCPN ROLLS IN FOR THU INTO FRI. AS OF MID AFTERNOON THERE WERE A
FEW PATCHES OF MID CLOUDS MOVING INTO THE WESTERN FA. A FEW ECHOES
WERE EVEN SHOWING UP ON RADAR BUT THINK THIS IS VIRGA AT MOST.
LOOKING AT MAINLY CLEAR SKIES TONIGHT WITH LIGHT WINDS. THE THIN
SMOKE LAYER WILL CONTINUE TO OVERSPREAD THE AREA TOO...BUT IT DOES
APPEAR TO BE PRETTY THIN AT THIS POINT. THERE WAS SOME PATCHY FOG
AROUND THIS MORNING...BUT IT WAS ISOLATED TO JUST A FEW RIVER
VALLEYS. THINK THE THIN SMOKE LAYER OVER THE FA WED WILL BE LIKE
A CIRRUS LAYER. HIGHS LOOKING A FEW DEGREES WARMER THAN TODAY.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 312 PM CDT TUE AUG 25 2015
MODELS ARE DELAYING THE ONSET OF THE THU PCPN CHANCES TO THE
AFTERNOON TIME FRAME...AND MAINLY ALONG/SOUTH OF HIGHWAY 2. THESE
CHANCES WILL SPREAD INTO THE EAST BY THU. NOT LOOKING LIKE A LOT
OF PCPN FOR THIS AREA AS THE MAIN PCPN SWATH STAYS WELL TO THE
SOUTH AND EAST.
SATURDAY TO TUESDAY...OVERALL DRY WEATHER ACROSS THE NORTHERN PLAINS
FOR THE UPCOMING WEEKEND AND INTO NEXT WEEK. 500MB UPPER LEVEL RIDGE
WILL BE RESPONSIBLE FOR ABOVE NORMAL TEMPS AND THE DRY FORECAST. A
SHORT WAVE WILL BEGIN TO IMPINGE ON THE RIDGE BY MONDAY BRINGING A
SLGT CHC OF THUNDER TO THE WESTERN AREAS AND THE ENTIRE AREA BY
TUESDAY. WITH WEEKEND HIGHS IN THE 80S THE MAX TEMPS WILL BE 5 TO 10
DEGREES ABOVE NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1134 PM CDT TUE AUG 25 2015
VFR CONDITIONS WILL CONTINUE...THERE COULD BE SOME PATCHY SHALLOW
FOG IN SOME SPOTS BUT DO NOT THINK IT WILL AFFECT TAF SITES AT
THIS TIME. SOME SMOKE FROM WESTERN FIRES WILL CONTINUE BUT THINK
IT WILL STAY HIGH LEVEL AT THIS POINT. LIGHT AND VARIABLE WINDS
WILL PICK UP OUT OF THE SOUTHEAST BY TOMORROW AFTERNOON.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...GODON
LONG TERM...GODON/JK
AVIATION...JR
AREA FORECAST DISCUSSION
NWS TULSA OK
541 AM CDT WED AUG 26 2015
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
LIGHT FOG WILL BE POSSIBLE AT BVO/RVS THROUGH ABOUT 14Z. VFR
CONDITIONS AND LIGHT WINDS WILL PREVAIL AT ALL TERMINALS
THEREAFTER.
&&
.PREV DISCUSSION... /ISSUED 239 AM CDT WED AUG 26 2015/
DISCUSSION...
WE`LL HAVE A PLEASANT START TO THE DAY WITH TEMPS IN THE 50S/60S
AND VERY COMFORTABLE DEWPOINTS. BOTH THE NAM AND HRRR HINT AT SOME
WEAK CONVECTION THIS MORNING IN THE DEVELOPING MID-CLOUD DECK
CURRENTLY STREAMING INTO CENTRAL OK...BUT INDICATIONS ARE THAT ANY
ACTIVITY WOULD BE JUST WEST OF OUR AREA. OTHERWISE...EXPECT
ANOTHER NICE AFTERNOON WITH TEMPS RUNNING A FEW DEGREES WARMER
THAN YESTERDAY.
AN UPPER SYSTEM WILL MOVE INTO THE CENTRAL PLAINS LATER THIS
WEEK...BRINGING A WEAK MID-LEVEL SHEAR AXIS AND SURFACE FRONT INTO
THE AREA. BROAD SURFACE RIDGING ACROSS THE GULF WILL LIMIT MOST OF
THE DEEPER MOISTURE RETURN...SO CHANCES/COVERAGE OF PRECIPITATION
FOR FRIDAY INTO EARLY SATURDAY WILL REMAIN LOW.
THE UPPER RIDGE WILL STRENGTHEN AGAIN LATE IN THE WEEKEND AND
INTO EARLY NEXT WEEK...WITH SEVERAL DAYS OF MILD OVERNIGHT LOWS
AND SEASONALLY HOT DAYTIME TEMPS IN STORE.
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
AVIATION...22
AREA FORECAST DISCUSSION
NWS TULSA OK
239 AM CDT WED AUG 26 2015
.DISCUSSION...
WE`LL HAVE A PLEASANT START TO THE DAY WITH TEMPS IN THE 50S/60S
AND VERY COMFORTABLE DEWPOINTS. BOTH THE NAM AND HRRR HINT AT SOME
WEAK CONVECTION THIS MORNING IN THE DEVELOPING MID-CLOUD DECK
CURRENTLY STREAMING INTO CENTRAL OK...BUT INDICATIONS ARE THAT ANY
ACTIVITY WOULD BE JUST WEST OF OUR AREA. OTHERWISE...EXPECT
ANOTHER NICE AFTERNOON WITH TEMPS RUNNING A FEW DEGREES WARMER
THAN YESTERDAY.
AN UPPER SYSTEM WILL MOVE INTO THE CENTRAL PLAINS LATER THIS
WEEK...BRINGING A WEAK MID-LEVEL SHEAR AXIS AND SURFACE FRONT INTO
THE AREA. BROAD SURFACE RIDGING ACROSS THE GULF WILL LIMIT MOST OF
THE DEEPER MOISTURE RETURN...SO CHANCES/COVERAGE OF PRECIPITATION
FOR FRIDAY INTO EARLY SATURDAY WILL REMAIN LOW.
THE UPPER RIDGE WILL STRENGTHEN AGAIN LATE IN THE WEEKEND AND
INTO EARLY NEXT WEEK...WITH SEVERAL DAYS OF MILD OVERNIGHT LOWS
AND SEASONALLY HOT DAYTIME TEMPS IN STORE.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 90 66 92 71 / 0 0 0 10
FSM 89 65 91 67 / 0 0 10 0
MLC 90 62 92 67 / 0 0 10 10
BVO 90 62 91 68 / 0 0 0 20
FYV 86 58 87 62 / 0 10 10 0
BYV 84 58 85 60 / 0 10 10 0
MKO 89 64 90 67 / 0 0 10 0
MIO 89 61 91 66 / 0 10 10 10
F10 89 65 91 68 / 0 0 0 10
HHW 93 64 93 65 / 0 0 10 0
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
SHORT TERM...22
LONG TERM....18
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
254 PM CDT WED AUG 26 2015
.SHORT TERM (TONIGHT THROUGH THURSDAY NIGHT)...
ISOLATED SHOWERS HAVE DEVELOPED OVER THE HILL COUNTRY AND EDWARDS
PLATEAU. THE LATEST TEXAS TECH WRF AND HRRR RUNS INDICATE THIS
ACTIVITY WILL REMAIN ISOLATED AND BARELY BRING MEASURABLE RAIN TO
ONLY A FEW SPOTS. WE HAVE REMOVED THE CHANCE FOR DOWNDRAFT WINDS
IN THE HAZARDOUS WEATHER OUTLOOK. OTHERWISE...WE EXPECT THE
SHOWERS TO QUICKLY DIE BY SUNSET. DRY AIR CONTINUES TO FILTER INTO
THE REGION...AND WHEN COUPLED WITH SUBSIDENCE BELOW THE UPPER
LEVEL RIDGE...WE EXPECT MOSTLY CLEAR SKIES OVERNIGHT...WITH THE
EXCEPTION OF SOME LOW CLOUDS ALONG THE BALCONES ESCARPMENT.
&&
.LONG TERM (FRIDAY THROUGH WEDNESDAY)...
THE UPPER LEVEL RIDGE SLIDES A BIT WEST OVER THE NEXT FEW
DAYS...WITH A RESULTING DROP IN HIGH AND LOW TEMPERATURES. EARLY
MORNINGS WILL BE PLEASANT FOR THE TIME OF YEAR...BUT AFTERNOONS
STILL WITH NEAR TO SLIGHTLY ABOVE NORMAL TEMPERATURES. A CUTOFF
LOW/TROUGH EVENTUALLY CARVES OUT OVER NORTHEAST TEXAS EARLY NEXT
WEEK...AND COMBINES WITH THE REMNANTS OF ERIKA TO PRODUCE A
LONGWAVE TROUGH OVER THE EASTERN U.S.. GULF MOISTURE WILL COINCIDE
WITH THE TROUGH DEVELOPMENT...AND HENCE BRING A CHANCE OF RAIN BY
THE MIDDLE OF NEXT WEEK. HOWEVER...THE WESTERN EDGE OF THE TROUGH
WILL HAVE A SHARP GRADIENT OF COVERAGE...SO AT THIS TIME WE WILL
KEEP POPS LOW. LOWER HEIGHTS AND CLOUDCOVER SHOULD DROP TEMPS TO
NEAR NORMAL...LOWER 90S FOR HIGHS AT MANY LOCATIONS...AND LOWS
AROUND 70...BY THE END OF NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 73 99 73 99 72 / - - 0 0 0
AUSTIN BERGSTROM INTL AIRPORT 70 98 70 97 69 / - - 0 0 0
NEW BRAUNFELS MUNI AIRPORT 72 99 72 98 70 / - - 0 0 0
BURNET MUNI AIRPORT 72 98 71 97 71 / - - 0 0 0
DEL RIO INTL AIRPORT 77 100 73 101 72 / - - 0 0 0
GEORGETOWN MUNI AIRPORT 71 98 72 98 72 / - - 0 0 0
HONDO MUNI AIRPORT 73 98 70 98 69 / - - 0 0 0
SAN MARCOS MUNI AIRPORT 72 98 71 97 70 / - - 0 0 0
LA GRANGE - FAYETTE REGIONAL 69 97 71 97 70 / - - 0 0 0
SAN ANTONIO INTL AIRPORT 75 98 73 97 72 / - - 0 0 0
STINSON MUNI AIRPORT 75 99 72 99 71 / - - 0 0 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...24
SYNOPTIC/GRIDS...26
PUBLIC SERVICE/DATA COLLECTION...LH
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1011 AM CDT WED AUG 26 2015
.UPDATE...
IT/S TOUGH TO FIND THE WEAK BOUNDARY OVER THE HILL COUNTRY/EDWARDS
PLATEAU...BUT ONCE MIXING COMMENCES WE EXPECT IT TO LIE ROUGHLY
ALONG I-10 NORTH OF SAN ANTONIO AND ALONG 1-37 SOUTH OF SAN
ANTONIO. RECENT HRRR RUNS POINT TOWARD CONVECTIVE INITIATION ALONG
THIS BOUNDARY AROUND 19-20Z...WITH STORMS THEN MOVING/PROPAGATING
WEST-SOUTHWEST THROUGH THE EDWARDS PLATEAU AND POSSIBLY INTO THE
RIO GRANDE PLAINS. WILL SEND AN UPDATE SHORTLY TO RE-TREND HOURLY
VARIABLES THOUGH 00Z...BUT THE MAIN FORECAST ADJUSTMENT IS TO RE-
ORIENT POPS ALONG AND WEST OF THE BOUNDARY LOCATION.
&&
.PREV DISCUSSION... /ISSUED 611 AM CDT WED AUG 26 2015/
AVIATION...
ISOLD SHRA/TSRA ARE EXPECTED TODAY. HOWEVER...WILL NOT MENTION AT
THE TAF SITES AS PROBS 20 OR LESS. WILL MONITOR RADAR AND MODEL
TRENDS FOR POSSIBLE UPDATES TO MENTION. VFR FLYING CONDITIONS WILL
PREVAIL TODAY THROUGH THURSDAY MORNING. HOWEVER...PATCHY STRATUS
AT MVFR LEVEL FROM KBAZ TO KHDO TO KCOT TO KBEA WILL PERSIST
THROUGH MID MORNING. BRIEF MVFR/IFR CIGS/VSBYS ARE ALSO POSSIBLE
IN SHRA/TSRA. E TO SE WINDS 10 KTS OR LESS PREVAIL. EXCEPT...WIND
GUSTS UP TO 35 KTS ARE POSSIBLE IN/NEAR SHRA/TSRA.
PREV DISCUSSION... /ISSUED 328 AM CDT WED AUG 26 2015/
SHORT TERM (TODAY THROUGH THURSDAY)...
A QUASI STATIONARY BOUNDARY WILL CONTINUE ITS SLOW TREK WESTWARD
TODAY AND WITH IT A SLIGHT CHANCE FOR SOME ISOLATED THUNDERSTORMS.
RAP FORECAST SOUNDINGS ARE ADVERTISING PRETTY DRY AIR EAST OF THE
BOUNDARY EFFECTIVELY CUTTING OFF ANY CHANCES FOR PRECIP.
HOWEVER...TO THE WEST...INSTABILITY AND LOW LEVEL LAPSE RATES
SHOULD BE ENOUGH TO FIRE SOME CONVECTION BY THE TIME CONVECTIVE
TEMPERATURES REACH THE MID 90S OR BY JUST AFTER NOON. HI RES
MODELS ARE SHOWING SOME VARIABILITY IN THE COVERAGE BUT EVEN THE
MORE ROBUST OUTCOMES ARE SHOWING ONLY ISOLATED CELLS FIRING WEST
OF THE BOUNDARY AS IT PROGRESSES WEST. THERE ARE A LOT OF FACTORS
THAT WILL PROHIBIT SIGNIFICANT GROWTH OF ANY UPDRAFTS TODAY BUT
THERE IS STILL THE POSSIBILITY OF SOME GUSTY WINDS WITH THE DRY
LOW LEVELS. ALTHOUGH WITH PWAT VALUES EXPECTED TO FALL BELOW 1.5
INCHES AND A VERY DRY COLUMN ABOVE 700 MB...THERE PROBABLY WONT BE
ENOUGH PRECIP GENERATED FOR SIGNIFICANT DOWNBURST WINDS.
THURSDAY SHOULD BE ANOTHER HOT DAY BUT WITH SOME WELCOME DRYNESS
AS DEWPOINTS LOOK TO RISE INTO THE UPPER 60S IN THE SOUTHERN HALF
OF THE CWA AND LOWER 60S UP NORTH. SHOULD RESULT IN LOW RELATIVE
HUMIDITIES THURSDAY AFTERNOON.
LONG TERM (THURSDAY NIGHT THROUGH TUESDAY)...
AN UPPER LEVEL LOW WILL INTENSIFY OVER THE ROCKIES AND WALTZ
AROUND THE UPPER RIDGE AXIS THROUGH THE WEEK WHICH WILL
EFFECTIVELY SHIFT THE RIDGE CENTER FARTHER WESTWARD BY THE
WEEKEND. THIS WILL ALLOW A WEAK LOW PRESSURE SYSTEM JUST OFF THE
COAST TO CREEP ONSHORE AND UP THE RIO GRANDE VALLEY BY EARLY NEXT
WEEK. SEEMS THIS OUTCOME IS FAIRLY WELL AGREED UPON BY BOTH THE
GFS AND ECMWF. DURING THIS TRANSITION PERIOD OVER THE
WEEKEND...VERY LIGHT WINDS AT THE SURFACE AND ALOFT WILL ALLOW FOR
CONDITIONS FAVORABLE FOR THE SEA BREEZE TO PUSH WELL NORTHWEST
INTO OUR CWA. WITH A COUPLE DAYS OF THIS OCCURRING...LOW LEVEL
MOISTURE WILL BE SPREAD INTO THE COASTAL PLAINS AND SOUTH TEXAS.
WHAT THIS MEANS FOR EARLY NEXT WEEK IS THE OPPORTUNITY FOR SOME
RAINFALL TUESDAY AND WEDNESDAY AS WELL AS CLOUD COVER AND MOST
NOTABLY...A DECREASE IN MAX TEMPS. TAKING A LOOK AT THE LONG RANGE
TEMPERATURE GUIDANCE...MEX HIGHS FOR THE PLATEAU MAY NOT EVEN
REACH 90 BY NEXT WEDNESDAY. WOULDNT THAT JUST BE SWELL?
BEYOND THAT...THE UPPER LOW WILL CONTINUE TO WEAKEN AND MOVE OFF
TO THE NORTHEAST ALLOWING RIDGING TO SHIFT EASTWARD AGAIN TOWARDS
CENTRAL TEXAS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 97 72 98 73 99 / 10 0 0 0 0
AUSTIN BERGSTROM INTL AIRPORT 95 69 96 69 97 / 10 0 0 0 0
NEW BRAUNFELS MUNI AIRPORT 98 72 99 71 98 / 10 0 0 0 0
BURNET MUNI AIRPORT 95 72 97 71 97 / 10 0 0 0 0
DEL RIO INTL AIRPORT 100 77 101 73 100 / 20 0 0 0 0
GEORGETOWN MUNI AIRPORT 96 71 97 71 98 / 10 0 0 0 0
HONDO MUNI AIRPORT 98 73 98 69 98 / 20 10 0 0 0
SAN MARCOS MUNI AIRPORT 96 72 97 71 97 / 10 0 0 0 0
LA GRANGE - FAYETTE REGIONAL 95 69 97 71 97 / 10 - 0 0 0
SAN ANTONIO INTL AIRPORT 98 75 97 73 97 / 20 - 0 0 0
STINSON MUNI AIRPORT 98 74 99 72 98 / 20 - 0 0 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...24
SYNOPTIC/GRIDS...26
PUBLIC SERVICE/DATA COLLECTION...LH
AREA FORECAST DISCUSSION
NWS PORTLAND OR
235 AM PDT WED AUG 26 2015
.SYNOPSIS...AN UPPER LOW OFF OF THE BRITISH COLUMBIA COAST WILL
PRODUCE SOUTHWEST FLOW ALOFT ACROSS THE PACIFIC NORTHWEST THE NEXT
SEVERAL DAYS. THE MAIN IMPACT FROM THIS LOW WILL BE A SLOWLY
DEVELOPING MARINE LAYER ALONG THE COAST THAT WILL NOT EXTEND FAR
INLAND. WEAK DISTURBANCES ROTATING AROUND THE LOW WILL GIVE A SLIGHT
CHANCE OF THUNDER NEAR THE CENTRAL OREGON CASCADE CREST THE NEXT FEW
DAYS WITH THE MAIN ACTIVITY MOVING OUT INTO CENTRAL OREGON. THE LOW
WILL MOVE ONSHORE LATE IN THE WEEK AND ON THE WEEKEND WITH AN
INCREASING GOOD CHANCE OF SHOWERS AND POSSIBLY THE FIRST GOOD WETTING
RAIN IN QUITE SOME TIME.
&&
.SHORT TERM...NOT MUCH CHANGE IN THE WEATHER EXPECTED TODAY AS A
LARGE UPPER LOW REMAINS OFF THE COAST NEAR 140W...AND A SW FLOW
ALOFT CONTINUES. SURFACE RIDGE JUST OFF THE COAST ALSO EXPECTED TO
REMAIN...RESULTING IN A CONTINUED ONSHORE FLOW. MODELS INDICATE
LITTLE CHANGE TO AIR MASS TODAY WITH H8 TEMPS OVER THE INTERIOR
EXPECTED TO REMAIN ON THE ORDER OF 16 DEG C...WHICH SHOULD KEEP
TEMPS CLOSE TO NORMAL. A SHORTWAVE IS SEEN IN WATER VAPOR PICTURES
EARLY THIS MORNNING S OF 40N NEAR 135W AND EXPECTED TO LIFT ACROSS
THE S PART OF THE FORECAST AREA THIS EVENING. FORECAST INSTABILITY
OF THE AIR MASS IN THE MODELS HOWEVER IS MARGINAL AS SEEN IN MODEL
SOUNDINGS...AND WITH THE FLOW A LITTLE W OF S...WHATEVER SMALL
CHANCE THERE IS FOR THUNDER THIS AFTERNOON WILL LIKELY BE LIMITED TO
THE CREST AND POINTS E.
THE SW FLOW ALOFT CONTINUES THU AND CHANGES TO THE AIR MASS APPEAR
MINIMAL EXCEPT FOR AN OVERALL INCREASE IN MOISTURE AND CLOUDS. WILL
CONTINUE TO CARRY A MENTION FOR SOME DRIZZLE ALONG THE COAST AS
SUGGESTED BY EC QPF FIELDS...BUT THE THREAT FOR PRECIPITATION
IMPROVES MORE THU NIGHT INTO FRI AS MOISTURE CONTINUES TO DEEPEN AND
THE UPPER TROUGH BEGINS TO INCH CLOSER. INITIAL THREAT FOR RAIN WILL
BE LIMITED PRIMARILY TO COASTAL AREAS THU NIGHT AS A WEAK FRONT
PUSHES IN AND ONSHORE COMPONENT OF LOW LEVEL FLOW STRENGTHENS.
MODELS IN GOOD AGREEMENT IN SPREADING THE THREAT FOR RAIN INLAND FRI
AS A SHORTWAVE ROUNDS THE BASE OF THE LOW AND APPROACHES THE COAST
PUSHING THE WEAK BAROCLINIC ZONE FURTHER IN. BEST CHANCES ON FRI
WILL REMAIN ON THE COAST HOWEVER...AND WITH CONFIDENCE IN MODELS
INCREASING WILL CARRY LIKELY POPS FOR COASTAL AREAS FRI. INCREASED
THREAT FOR RAIN AND THICKER CLOUDS WILL RESULT IN COOLER TEMPS FRI.
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...FRIDAY NIGHT
THROUGH TUESDAY...MODELS ARE IN PRETTY GOOD AGREEMENT THAT THE UPPER
LOW CURRENTLY OFF THE COAST OF BRITISH COLUMBIA WILL DIG SOUTHWARD
OVER THE WEEKEND BRINGING COOLER AND WETTER WEATHER CONTINUING INTO
EARLY NEXT WEEK. A SURFACE FRONT OUT AHEAD OF THE MAIN UPPER LEVEL
SYSTEM WILL MOVE ONSHORE FRIDAY NIGHT INTO SATURDAY MORNING WHICH
MODELS PREDICT WILL BRING WIDESPREAD RAIN ACROSS WESTERN WASHINGTON
AND OREGON. BY SATURDAY AFTERNOON RAIN WILL BECOME MORE SHOWERY
BEHIND THE FRONT AS AN UNSTABLE AIRMASS MOVES OVER THE AREA. THE
UPPER LEVEL SYSTEM MOVES ACROSS THE AREA LATE SATURDAY NIGHT OR EARLY
SUNDAY WHICH WILL BRING ANOTHER ROUND OF RAIN TO AT LEAST THE
NORTHERN HALF OF OUR AREA...THOUGH PROBABLY LESS THAN WE SEE ON
SATURDAY. COOLER WEATHER CONTINUES WITH CHANCES FOR SHOWERS THROUGH
EARLY NEXT WEEK AS WE STAY UNDER NORTHWESTERLY FLOW ALOFT. MODELS
HAVE BEEN INCONSISTENT WITH WHEN THE NEXT SHORTWAVE WILL ARRIVE SO
HAVE LEFT A SLIGHT CHANCE OF SHOWERS THROUGH TUESDAY...THOUGH AS OF
NOW IT LOOKS LIKE MONDAY COULD BE FAIRLY DRY.
-MCCOY
&&
.AVIATION...WITH LITTLE CHANGE TO THE OVERALL WEATHER
PATTERN...EXPECT TONIGHT TO SIMILAR TO LAST NIGHT WITH SOME PATCHY
MVFR STRATUS FORMING ALONG THE S WASHINGTON AND N OREGON COAST AND
PATCHY MVFR VIS ALONG THE CENTRAL OREGON COAST. VFR CONDITIONS
SHOULD RETURN TO THE COAST BY MID MORNING WED. VFR TO REMAIN IN
CONTROL FOR THE NEXT 24 HRS FOR THE INTERIOR TAF SITES. A THIN
SMOKE LAYER WILL CONTINUE TO AFFECT THE CASCADES AND SOUTHERN
WILLAMETTE VALLEY THROUGH WEDNESDAY FROM FIRES OVER SW OREGON.
KPDX AND APPROACHES...VFR CONTINUES WITH A FEW HIGH CLOUDS AND
SOME RESIDUAL SMOKE AT HIGHER LEVELS...PARTICULARLY ON THE EASTERN
APPROACHES THAT MAY RESTRICT SLANTWISE VISIBILITIES BELOW AROUND
9000 FT. BOWEN/PYLE
&&
.MARINE...LITTLE CHANGE THROUGH WEDNESDAY. THERMAL TROUGH SITS
OVER SW OREGON AND NW CALIFORNIA...WITH HIGHER PRES REMAINING OVER
THE NE PAC. N TO NW WINDS OF 10 TO 15 KT TO CONTINUE. SEAS TO
REMAIN AT 4 TO 5 FT.
A PATTERN SHIFT LATER THIS WEEK WILL BRING LOW PRES
INTO THE REGION AND A TRANSITION TO SOUTHERLY WINDS BEGINNING THU.
CONFIDENCE IS INCREASING THAT A WELL-DEFINED FRONT WILL MOVE
THROUGH THE WATERS LATE FRI INTO SAT. THIS FRONT WILL LIKELY BRING
GUSTY S WINDS WITH GUSTS 25 TO 30 KT...WITH A LOW POSSIBILITY FOR
GALES SATURDAY AND SATURDAY NIGHT. SEAS INCREASE STARTING LATE
FRI...AND BUILD TO 7 TO 9 FT SATURDAY WITH A RATHER CONFUSED SEA
STATE INCLUDING SOME WIND WAVE/FRESH SWELL COMBINATION ALONG WITH
A FEW SIMILARLY SIZED SWELL COMPONENTS. AN UNSETTLED WEATHER
PATTERN LOOKS LIKELY THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK.
BOWEN/PYLE
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...NONE.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
Area Forecast Discussion
National Weather Service Spokane WA
950 PM PDT TUE AUG 25 2015
.SYNOPSIS...
Warm, dry and smoky conditions will continue this week. Strong
inversions will likely lead to poor air quality due to high
concentrations of wildfire smoke in the mornings. There is a
chance of dry thunderstorms Wednesday night. The next significant
round of wind, showers, and cooler weather looks to arrive for the
upcoming weekend.
&&
.DISCUSSION...
Evening update: forecast is generally on track. I increased cloud
cover some and tweaked the Wednesday morning lows, but they are
expected to be similar this morning. The elevated and isolated and
largely thunderstorm threat in the forecast still seems warranted.
There is very little to the shortwave tracking up through OR
into southern WA this hour, but there remains some elevated
instability and the newest HRRR and 00Z Hi-Res NAM do indicated a
few possible elevated showers passing. Still not much but more
than earlier runs. Overall, I`m not expecting much to develop but
there is the possibility.
Additionally, the Red Flag Warning for dry, unstable conditions
was allowed to expire at 9 PM. The next few days will remain hot,
but overall High Level Haines index values appear to be lower (in
the 3 to 4 range). Generally we`d like around 5 or 6, but still we
will have to monitor the situation closely for anything that may
lead to critical fire behavior. /J. Cote`
&&
.AVIATION...
06Z TAFS: The region will remain in a southwest flow, with a weak
upper impulse pushing this evening into the overnight. Some
elevated instability will bring the off-chance of some
thunderstorms and sprinkles, but the risk of them passing a TAF
site at this time is too small to mention in the TAF forecast.
However between 06 to 12Z there may be some isolated thunder, with
the best chance at this time from MWH to GEG to COE. Smoke will
continue to impact some TAF sites. Given recent patterns, we are
expected VFR/MVFR conditions this evening, with a trend toward
mainly MVFR late overnight into Wednesday morning, before some
improvement in the afternoon again. Winds will be mainly light and
diurnal. /J. Cote`
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 61 90 63 89 62 84 / 10 10 10 10 10 10
Coeur d`Alene 56 91 57 89 57 84 / 10 10 10 10 10 10
Pullman 53 91 55 88 54 85 / 10 0 10 10 20 10
Lewiston 62 95 66 93 64 90 / 10 10 10 10 20 10
Colville 51 91 55 91 55 84 / 10 0 10 10 10 10
Sandpoint 49 88 51 88 51 83 / 10 10 10 10 20 10
Kellogg 55 91 55 88 55 84 / 10 0 10 20 20 10
Moses Lake 55 91 59 91 60 86 / 10 0 20 10 10 10
Wenatchee 62 92 68 92 67 81 / 10 0 10 10 10 20
Omak 57 91 61 91 60 82 / 10 0 10 10 10 20
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1110 PM CDT TUE AUG 25 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 325 PM CDT TUE AUG 25 2015
CHALLENGES TONIGHT THROUGH WEDNESDAY INCLUDE CLOUD TRENDS...
TEMPERATURES AND FOG POTENTIAL. SOME DIFFERENCES BETWEEN MODELS
WITH REGARD TO HOW QUICKLY CLOUDS DISSIPATE AND MOVE OUT TONIGHT...
BUT OTHERWISE IN GOOD AGREEMENT AND WILL USE A BLENDED SOLUTION.
25.20Z SURFACE LOW ACROSS SOUTHERN HUDSON BAY WILL FINALLY BEGIN
TO LIFT NORTH AND EAST TONIGHT...ALLOWING EXPANSIVE STRATOCUMULUS
DECK ACROSS THE ENTIRE GREAT LAKES REGION TO SLOWLY MOVE OUT OF
THE FORECAST AREA. 25.18Z RAP 1 KM 90 PERCENT RELATIVE HUMIDITY
CONTOUR HAS BEEN A GOOD PROXY TO CURRENT CLOUD COVER AND SHOWS
MOST CLOUDS DISSIPATE AND/OR MOVE EAST OF THE FORECAST AREA BY
25.06Z. THIS IDEA IS ALSO SUPPORTED BY LATEST NSSL SYNTHETIC
IR...SO EXPECT CLEARING TO OVERSPREAD THE FORECAST AREA OVERNIGHT.
WITH LIGHT WINDS DEEPENING TO AROUND 2000 FT AGL BY 25.09Z...THINK
SOME VALLEY FOG IS POSSIBLE AND WILL CONTINUE TO MENTION IN LATEST
FORECAST. TEMPERATURES TONIGHT WILL BOTTOM OUT FROM THE MID 40S TO
LOWER 50S.
WEDNESDAY WILL BE MOSTLY SUNNY AND DRY AS SURFACE HIGH PRESSURE
SLIDES ACROSS THE UPPER MS RIVER VALLEY. WINDS WILL BE LIGHT FROM
THE NORTH-NORTHWEST WITH AFTERNOON HIGHS INTO THE UPPER 60S TO MID
70S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 325 PM CDT TUE AUG 25 2015
SURFACE RIDGE AXIS MOVES OVER LAKE MICHIGAN BY 25.12Z...BUT LIGHT
WINDS WILL CONTINUE THROUGH THE MORNING...DEEPENING TO NEARLY 6000
FT AGL. FOG POTENTIAL WILL HINGE ON POSSIBLE HIGH CLOUDS...BUT
OTHERWISE A GOOD CHANCE AND WILL KEEP MENTION OF PATCHY VALLEY
FOG.
CLOUD COVER AND SOUTHERLY WINDS WILL INCREASE THROUGH THE DAY ON
THURSDAY AHEAD OF THE NEXT LOW PRESSURE SYSTEM. ANY PRECIPITATION
WILL REMAIN WEST OF THE FORECAST AREA...EXCEPT FOR A SMALL CHANCE
LATE IN THE EVENING MAINLY WEST OF THE HIGHWAY 52 CORRIDOR. RISING
925 TO 850 HPA TEMPERATURES WILL ALLOW AFTERNOON HIGHS TO REACH
THE MID TO UPPER 70S.
FRIDAY NOW LIKELY TO BE CLOUDY AND WET AS AN EASTERN PACIFIC
TROUGH UNDERCUTS THE WESTERN CONUS 500 HPA RIDGE AND MOVES INTO
THE UPPER MIDWEST. 25.12Z MODEL SUITE PRODUCES A WELL DEFINED
DEFORMATION PRECIPITATION AXIS ALONG ENHANCED 850 TO 700 HPA
FRONTOGENESIS NORTH OF THE SURFACE LOW. ALTHOUGH THE GFS/ECMWF
SURFACE LOW TRACKS ARE SIMILAR...MOVING FROM EAST-CENTRAL NE
ACROSS SOUTHERN IA THROUGH THE DAY...THE ECMWF PAINTS THE HIGHEST
RAINFALL A BIT FARTHER SOUTH COMPARED TO THE GFS/NAM WHICH ARE
HIGHEST ACROSS THE FORECAST AREA. THE PAST THREE RUNS OF THE GFS
HAVE BEEN SIMILAR...LENDING HIGHER CONFIDENCE TO ITS NORTHERN
SOLUTION. WILL INCREASE POPS INTO THE LIKELY CATEGORY ON FRIDAY.
HOWEVER...INSTABILITY STILL LOOKS VERY WEAK AND WILL CAP
THUNDERSTORM CHANCES TO 20 PERCENT WITH LIGHT TO MODERATE SHOWERS
BEING THE DOMINATE MODE. STILL A BIT EARLY TO GET TOO SPECIFIC
WITH RAINFALL AMOUNTS...BUT SOME AREAS COULD SEE AMOUNTS IN
EXCESS OF AN INCH THROUGH FRIDAY NIGHT. WITH CLOUDS AND RAIN...
FRIDAY WILL BE COOL WITH HIGHS IN THE UPPER 60S TO NEAR 70
DEGREES.
SOME LINGERING SHOWERS POSSIBLE SATURDAY...ESPECIALLY EAST OF THE
MS RIVER...BUT OTHERWISE SHOULD SEE IMPROVING CONDITIONS WITH
DECREASING CLOUD COVER AND RAIN CHANCES FROM WEST TO EAST. HIGHS
WILL REBOUND BACK INTO THE MID 70S. SUNDAY THROUGH TUESDAY LOOK
DRY WITH NO MAJOR SYSTEMS ON THE HORIZON. BIGGER CONCERN WILL BE
RISING TEMPERATURES AS 500 HPA RIDGE AXIS FOLDS OVER ACROSS THE
UPPER MIDWEST...RESULTING IN TEMPERATURES RISING INTO THE LOWER TO
MID 80S BY THE EARLY PART OF NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1110 PM CDT TUE AUG 25 2015
HIGH PRESSURE WORKS IN TONIGHT...AND WILL BE THE MAIN WEATHER
FEATURE THROUGH THU. WINDS WILL GENERALLY BE LIGHT AND NORTHERLY
THROUGH WED...THEN LIGHT EAST/VRB WED NIGHT.
WITH THE HIGH OVERHEAD...AND LIGHT SFC WINDS...VALLEY FOG BECOMES A
CONCERN. KLSE T/TD DIFF AT 03Z WAS 5 F...GOOD FOR OVERNIGHT FOG
FORMATION. SFC WINDS WERE CALM TO LIGHT. A NORTHERLY
DIRECTION...EVEN LIGHT...CAN BE PROHIBITIVE TO DENSE FOG AT KLSE.
MORE SIGNIFICANT IS THE DEPTH OF THE LIGHT WIND LAYER. RAP/HRRR/NAM
BUFKIT SOUNDINGS CONTINUE TO SUGGEST THIS LAYER DOESN/T DEEPEN UNTIL
AFTER 06Z. THIS MIGHT BE TOO SHORT OF A TIME TO ALLOW FOR EXTENSIVE
FOG IN THE VALLEY. BCFG BKN003 STILL LOOKS A BIT MORE LIKELY THAN
SUB 1/2SM FG AT THIS TIME...AND WILL LEAN THE FORECAST THIS WAY.
TRENDS WILL BE MONITORED AND ADJUSTMENTS MADE IF NEEDED.
THU MORNING SHOWS MORE PROMISE FOR FG AT KLSE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...ROGERS
LONG TERM...ROGERS
AVIATION...RIECK
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
207 AM MDT WED AUG 26 2015
.SHORT TERM...(TODAY THROUGH FRIDAY NIGHT)
ISSUED AT 300 AM MDT WED AUG 26 2015
TODAY...WATER VAPOR SATELLITE IMAGERY SHOWS A DECENT FETCH OF
SUBTROPICAL MOISTURE ADVECTING TOWARDS OUR REGION FROM UTAH AND
ARIZONA...WHICH WILL BE THE MAIN WEATHER PLAYER THE NEXT FEW DAYS.
THIS AFTERNOON...THE RIDGE ALOFT TRANSLATES INTO THE WESTERN HIGH
PLAINS AS THE NEXT WELL ADVERTISED NEGATIVELY TILTED SHORTWAVE
TROUGH ALOFT APPROACHES WESTERN WYOMING. ALTHOUGH IT WILL TAKE
AWHILE FOR LOW LEVELS TO BECOME MORE MOIST...IT APPEARS THERE WILL
BE ENOUGH MID LEVEL MOISTURE TO SPARK SCATTERED TO NUMEROUS SHOWERS
AND THUNDERSTORMS THIS AFTERNOON AND EVENING ALONG AND WEST OF
INTERSTATE 25...WITH LESSER CHANCES FURTHER EAST.
TONIGHT...SHORTWAVE TROUGH ALOFT MOVES SLOWLY OVERHEAD THUS KEEPING
SHOWER AND THUNDERSTORM CHANCES GOING ALL NIGHT THOUGH LESS THAN
CHANCES NEAR PEAK HEATING. THIS WILL PRODUCE A MILD NIGHT FOR LATE
AUGUST.
THURSDAY...THE SHORTWAVE TROUGH ALOFT MOVES INTO THE CENTRAL PLAINS
STATES...THOUGH THERE WILL STILL BE ENOUGH RESIDUAL LOW AND MID
LEVEL MOISTURE TO SPARK SCATTERED AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS...ALONG WITH COOLER TEMPERATURES DUE TO A PASSING COLD
FRONT AS WELL AS INCREASED CLOUD COVER.
THURSDAY NIGHT/FRIDAY/FRIDAY NIGHT...RIDGING ALOFT BECOMES MORE
PRONOUNCED WITH LOW AND MID LEVEL DRYING AND THUS LESS AND LESS
CHANCES FOR AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS...EXCEPT
NEAR THE MOUNTAINS DUE TO OROGRAPHICS AND DIFFERENTIAL HEATING.
.LONG TERM...(SATURDAY THROUGH TUESDAY)
ISSUED AT 300 AM MDT WED AUG 26 2015
STILL CONCERNS FOR STRONG WINDS SATURDAY OUT IN THE PANHANDLE.
GFS CONTINUES TO FORECAST 850MB WINDS OF 40-50KTS OUT OVER THE
PANHANDLE AFTER 00Z SUNDAY AND CONTINUING OVERNIGHT INTO SUNDAY.
ECMWF SHOWING SIMILAR WIND SPEEDS. DID BEGIN TO INCREASE SPEEDS
OUT THERE FOR SATURDAY NIGHT AND SUNDAY...BUT DO FEEL WE WILL
PROBABLY NEED TO INCREASE MORE.
700MB WINDS INCREASING WEST OF THE LARAMIE RANGE SATURDAY
AFTERNOON AS WELL. GFS SHOWING 700MB WINDS OF 20-25KTS SATURDAY
AFTERNOON...INCREASING TO 25-30KTS SUNDAY. COULD BE A FIRE CONCERN
SATURDAY AFTERNOON AS FORECAST AFTERNOON HUMIDITIES FORECAST DOWN
TO 15 PERCENT IN BOTH CONVERSE AND SOUTHWESTERN CARBON COUNTIES.
GUSTY WINDS CONTINUING INTO MONDAY AND TUESDAY AS A SHORTWAVE
MOVES THROUGH MONTANA. DRIER AIR WITH MORE WIDESPREAD LOW
AFTERNOON HUMIDITIES THROUGH THE FIRST PART OF NEXT WEEK. COULD BE
DEALING WITH RED FLAGS EACH DAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1047 PM MDT TUE AUG 25 2015
GETTING SOME LIGHTNING STRIKES JUST NORTH OF KRWL LATE THIS
EVENING. LATEST HRRR FORECAST RADAR SHOWS THIS ACTIVITY
DISSIPATING IN A FEW HOURS. MOISTURE FROM THE 4 CORNERS AREA
FORECAST TO MOVE NORTH INTO SOUTH CENTRAL WYOMING THIS AFTERNOON.
COULD SEE PREDOMINANT SHOWERS AND ISOLATED THUNDERSTORMS AT KRWL
AND KLAR AFTER 20Z OR SO...PERSISTING INTO THE EVENING HOURS.
&&
.FIRE WEATHER...
ISSUED AT 300 AM MDT WED AUG 26 2015
MINIMAL CONCERNS THROUGH FRIDAY. HOWEVER...ON
SATURDAY...HUMIDITIES AND WINDS WILL APPROACH CRITICAL LEVELS OVER
OUR NORTHERN AND WESTERN COUNTIES...THUS ELEVATING CONCERNS. EARLY
NEXT WEEK...MONDAY THROUGH WEDNESDAY...WE MAY HAVE A PROLONGED
CRITICAL FIRE WEATHER PERIOD DUE TO INCREASED WINDS AND LOW
HUMIDITIES IN THE AFTERNOONS AND EVENINGS.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...RUBIN
LONG TERM...GCC
AVIATION...GCC
FIRE WEATHER...RUBIN
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1050 PM MDT TUE AUG 25 2015
.UPDATE...
ISSUED AT 841 PM MDT TUE AUG 25 2015
RAISED POPS UP TO 20 PERCENT FOR WIDELY SCATTERED SHOWERS AND A
FEW TSTORMS ALONG AND WEST OF THE LARAMIE RANGE THROUGH LATE THIS
EVENING BEFORE DISSIPATING.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 222 PM MDT TUE AUG 25 2015
BROAD UPPER-LEVEL RIDGING EXTENDS ACROSS THE WESTERN HALF OF THE US
THIS AFTERNOON. THE RESULTING LARGE SCALE SUBSIDENCE IS CONTRIBUTING
TO GENERALLY WARM AND DRY CONDITIONS ACROSS THE CWA. RECENT WATER
VAPOR SATELLITE IMAGERY SHOWS A PLUME OF MONSOONAL MOISTURE LIFTING
NORTH OVER THE FOUR CORNERS REGION ON THE WEST SIDE OF THE RIDGE. SOME
OF THIS MOISTURE WAS ALREADY CREEPING INTO THE SNOWY AND SIERRA MADRE
MTNS AT 20Z...SO WE SHOULD SEE AN INCREASE IN MOUNTAIN CONVECTION AS
WE HEAD INTO THE LATE AFTERNOON/EVENING HOURS. MORE WIDESPREAD SHOWERS
AND THUNDERSTORMS STILL EXPECTED FROM WED AFTN THROUGH THU WITH THE
PASSAGE OF A STRONG PACIFIC COLD FRONT AND VIGOROUS MID-LEVEL SHORT
WAVE TROUGH. NAM/GFS/ECMWF ALL SUGGEST THE GREATEST PRECIP COVERAGE
ALONG AND WEST OF THE LARAMIE RANGE...WITH MAKES SENSE WITH GENERAL
WESTERLY FLOW AND THE TRAJECTORY OF THE BEST H7-H3 MOISTURE. BETTER
CHANCES FOR THE EASTERN PLAINS SHOULD COME AFTER 15Z THU AS MOST OF
THE MID LEVEL ENERGY AND ASSOCIATED MOISTURE PLUME SHIFTS SLOWLY TO
THE EAST. ONE MORE WARM DAY EXPECTED FOR WED PRE-FROPA. MUCH COOLER
FOR THU AS MOST OF THE MODELS SHOW H7 TEMPS PLUNGING FROM +16 C AT
00Z THU...TO BETWEEN +8 AND +10 C BY 18Z THU. INDEED AN IMPRESSIVE
TEMPERATURE SWING FOR A PACIFIC FRONT...ESPECIALLY FOR AUGUST. MAY
NEED TO REVISE TEMPERATURES DOWNWARD IN THE FUTURE IF IT LOOKS LIKE
PRECIP WILL BE HEAVIER OR MORE WIDESPREAD.
.LONG TERM...(THURSDAY THROUGH NEXT TUESDAY)
ISSUED AT 222 PM MDT TUE AUG 25 2015
MEDIUM TO LONG RANGE MODELS ARE CONSISTENT WITH THE PREVIOUS 12Z
AND 00Z RUNS...SHOWING UPPER LEVEL RIDGING BUILDING BACK INTO THE
FRONT RANGE ON FRIDAY. THIS RIDGE WILL GRADUALLY EXTEND EASTWARD
INTO THE GREAT PLAINS...ALLOWING SOUTHWEST FLOW ALOFT TO INCREASE
OVER WYOMING AND NEBRASKA. IT WILL BE WARM ON FRIDAY AND ESPECIALLY
DURING THE WEEKEND WITH HIGHS IN THE 80S TO MID 90S...WARMEST OVER
THE LOWER ELEVATIONS. MODELS ARE NOW SHOWING A BIT MORE MOISTURE
AND INSTABILITY OVER THE REGION AS SOME SUBTROPICAL MOISTURE
GRADUALLY ADVECTS NORTHWARD ON THE WESTERN SIDE OF THE UPPER LEVEL
RIDGE AXIS. THE 12Z ECMWF SHOWS SOME SHORTWAVE ENERGY PUSHING
NORTHEAST OVER THE FORECAST AREA BY EARLY NEXT WEEK...IMPROVING
THUNDERSTORM CHANCES MONDAY AND TUESDAY. EXPECT MOST OF THIS
ACTIVITY TO BE OVER THE MOUNTAINS...ALONG AND WEST OF THE I25
CORRIDOR...BUT A FEW THUNDER SHOWERS MAY PUSH FAR ENOUGH EAST TO
IMPACT WESTERN NEBRASKA AS WELL. INCREASED POP BETWEEN 15 TO 25
PERCENT FOR WIDELY SCATTERED THUNDER ACROSS THE HIGH VALLEYS AND
HIGH PLAINS EAST OF THE LARAMIE RANGE ACROSS SOUTHEAST WYOMING.
DAYTIME TEMPERATURES WILL CONTINUE TO BE ABOVE NORMAL AND IN THE
80S TO LOW 90S ACROSS THE AREA EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1047 PM MDT TUE AUG 25 2015
GETTING SOME LIGHTNING STRIKES JUST NORTH OF KRWL LATE THIS
EVENING. LATEST HRRR FORECAST RADAR SHOWS THIS ACTIVITY
DISSIPATING IN A FEW HOURS. MOISTURE FROM THE 4 CORNERS AREA
FORECAST TO MOVE NORTH INTO SOUTH CENTRAL WYOMING THIS AFTERNOON.
COULD SEE PREDOMINANT SHOWERS AND ISOLATED THUNDERSTORMS AT KRWL
AND KLAR AFTER 20Z OR SO...PERSISTING INTO THE EVENING HOURS.
&&
.FIRE WEATHER...
ISSUED AT 222 PM MDT TUE AUG 25 2015
WARM AND DRY CONDITIONS ARE OCCURRING ACROSS A LARGE PORTION OF THE
AREA THIS AFTERNOON. RELATIVE HUMIDITY VALUES BETWEEN 10 AND 15 PCT
ARE COMMON ACROSS SOUTHEAST WYOMING...BUT LIGHT WINDS TOPPING OUT
AROUND 10 MPH IN THE VEDAUWOO AREA ARE KEEPING CONCERNS MINIMAL.
THERE WILL NOT BE ANY FIRE WEATHER CONCERNS THROUGH THE END OF THE
WORK WEEK AS A COOLER AND MORE MOIST AIR MASS KEEPS HUMIDITIES
ABOVE 20 PCT ALONG WITH A HIGHER PROBABILITY FOR WETTING RAINS. A
WARMING AND DRYING TREND IS EXPECTED THIS WEEKEND ALONG WITH GUSTY
WINDS. NEAR CRITICAL FIRE WEATHER CONDITIONS ARE STILL EXPECTED
FOR SAT AND SUN.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...MJ
SHORT TERM...CLH
LONG TERM...TJT
AVIATION...GCC
FIRE WEATHER...CLH
AREA FORECAST DISCUSSION
NWS TUCSON AZ
925 PM MST THU AUG 27 2015
.SYNOPSIS...EXPECT DECREASED THUNDERSTORM ACTIVITY FRIDAY THEN
SCATTERED THUNDERSTORMS WILL RETURN ESPECIALLY FROM TUCSON EAST AND
SOUTH SATURDAY AND CONTINUE INTO NEXT WEEK. DAYTIME TEMPERATURES
WILL REMAIN ABOVE AVERAGE INTO EARLY NEXT WEEK...THEN HIGH
TEMPERATURES WILL TREND CLOSER TO NORMAL BY LATE NEXT WEEK.
&&
.DISCUSSION...VERY INTERESTING EVENING AS MOST OF THE ACTIVITY HAS
BEEN DRIVEN BY THUNDERSTORM OUTFLOW INTERACTIONS. ONE OF THE
OUTFLOWS THAT STARTED IN EASTERN PINAL COUNTY EARLIER THIS
EVENING HAS PUSHED S INTO NRN MEXICO. THERE WERE A FEW STRONG STORMS
EARLY IN THE EVENING ESPECIALLY N OF ARIVACA AND ON SE SIDE OF
TUCSON METRO AREA. SOUTH OF THE BORDER ACROSS NORTHERN SONORA THERE
WAS AN MCS. NORTH BOUND OUTFLOWS FROM THIS SYSTEM WILL LIKELY
INTERACT WITH SOUTH OF OUTFLOWS THAT PUSHED ACROSS THE INTERNATIONAL
BORDER FOR THE POSSIBILITY OF NEW THUNDERSTORM DEVELOPMENT SOUTH OF
THE BORDER. THESE STORMS CAN THEN SEND OUTFLOWS NORTH INTO COCHISE
COUNTY FOR NEW STORM DEVELOPMENT OVERNIGHT. LATEST HRRR RUN HINTING
AT THIS. WILL RUN. ON THE EVENING UPDATE WILL INCREASE POPS
OVERNIGHT ALONG THE INTERNATIONAL BORDER. CHECK PREVIOUS DISCUSSION
BELOW FOR THE REMAINDER OF THE FORECAST.
&&
.AVIATION...VALID THRU 29/00Z.
ISOLD-SCTD -TSRA/-SHRA...MAINLY S AND E OF KTUS THRU 28/12Z.
ISOLD TO PERHAPS SCTD -TSRA/-SHRA WILL THEN PREVAIL MAINLY E OF
KTUS FRI AFTN. MVFR CONDS AND BRIEF WIND GUSTS OF 35-45 KTS WILL
OCCUR WITH THE STRONGER T-STORMS. OTHERWISE...CLOUD DECKS WILL
GENERALLY RANGE FROM 10-15K FT AGL AND SURFACE WIND WILL MAINLY BE
LESS THAN 10 KTS. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...THUNDERSTORMS WILL BE LIMITED TO MAINLY NEAR THE
MOUNTAINS EAST OF TUCSON FRIDAY. SCATTERED THUNDERSTORMS WILL RETURN
TO MUCH OF SOUTHEAST ARIZONA SATURDAY...THEN SCATTERED THUNDERSTORMS
WILL PREVAIL MAINLY FROM TUCSON EAST AND SOUTH SUNDAY THROUGH
THURSDAY. BRIEF STRONG...GUSTY AND ERRATIC WINDS WILL ACCOMPANY THE
STRONGER THUNDERSTORMS. OTHERWISE...GENERALLY LIGHT TERRAIN DRIVEN
WINDS WILL OCCUR INTO NEXT WEEK.
&&
.PREV DISCUSSION...MARKEDLY LESS COVERAGE OF SHOWERS/TSTMS IS ON TAP
FRI AFTERNOON AS HIGH PRESSURE ALOFT BECOMES CENTERED OVER THE AREA.
SOME MESOSCALE MODELS SUGGEST THAT ANY THUNDERSTORMS THAT OCCUR FRI
AFTERNOON/EVENING WILL BE CONFINED ONLY NEAR MOUNTAINS EAST OF
TUCSON. FOR NOW...HAVE OPTED FOR ISOLATED TO SCATTERED SHOWERS/TSTMS
MAINLY FROM TUCSON EWD TO THE NEW MEXICO BORDER FRI AFTN/EVENING.
THE UPPER HIGH IS PROGGED TO REMAIN QUASI-STATIONARY OVER THE AREA
SAT. HOWEVER...HAVE ADJUSTED POPS UPWARD FAIRLY SUBSTANTIALLY ACROSS
MUCH OF THE AREA AS MODELS SUGGEST THAT A GENERALLY NELY STEERING
FLOW REGIME MAY DEVELOP. THUS...SCATTERED SHOWERS/TSTMS ARE EXPECTED
TO OCCUR ACROSS MUCH OF THIS FORECAST AREA SAT AFTERNOON/EVENING.
THEREAFTER...THE MID-LEVEL STEERING FLOW IS PROGGED TO BECOME SWLY
SUN AND CONTINUE INTO THURSDAY AS UPPER RIDGE AXIS WILL BE OVER THE
CENTRAL/SRN CONUS PLAINS...AND AN UPPER TROUGH BECOMES ESTABLISHED
YET AGAIN ADJACENT THE WEST COAST. THIS PATTERN SHOULD YIELD
ISOLATED TO SCATTERED MAINLY AFTERNOON AND EVENING SHOWERS/TSTMS SUN-
THUR. ABOVE NORMAL DAYTIME TEMPERATURES WILL ALSO PREVAIL FRI THRU
MON OR TUE...THEN HIGH TEMPS WILL TREND CLOSE TO SEASONAL NORMALS BY
NEXT THUR.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
!--NOT SENT--!
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
339 AM EDT FRI AUG 28 2015
.SYNOPSIS...
A FRONTAL BOUNDARY WILL REMAIN STALLED NEAR THE COAST TODAY. A
LARGE AREA OF SURFACE HIGH PRESSURE CENTERED OVER THE GREAT LAKES
REGION WILL SLIDE EAST TO THE ATLANTIC COAST FOR THE WEEKEND.
INCREASING ATMOSPHERIC MOISTURE WILL DRIFT NORTH INTO OUR REGION
THIS WEEKEND. TROPICAL CYCLONE ERIKA IS EXPECTED TO APPROACH
SOUTHERN FLORIDA ON SUNDAY. REFER TO THE LATEST ADVISORY ON ERIKA
ISSUED BY THE NATIONAL HURRICANE CENTER.
&&
.NEAR TERM /THROUGH TODAY/...
EARLY THIS MORNING...LOW CLOUDS HAVE BEGUN TO DEVELOP EARLY THIS
MORNING...ESPECIALLY ACROSS THE WESTERN HALF OF THE FORECAST AREA
GIVEN DRY AIR ALOFT. OVERNIGHT LOWS WILL ONCE AGAIN RANGE FROM THE
MID 60S TO THE LOWER 70S.
TODAY...AN UPPER LEVEL TROUGH EXTENDING FROM THE OHIO RIVER
VALLEY TO THE GULF OF MEXICO WILL WEAKEN AND LIFT NORTH TODAY. THE
FRONTAL BOUNDARY IS EXPECTED TO REMAIN STALLED NEAR THE COAST.
SURFACE HIGH PRESSURE WILL CONTINUE TO RIDGE IN FROM THE NORTH
PRODUCING NORTHEASTERLY/EASTERLY FLOW. MODELS SHOW A STRONG
GRADIENT IN PRECIPITABLE WATER FROM NORTH TO SOUTH ACROSS THE
AREA WITH THE BEST MOISTURE SOUTH. MODEL SOUNDINGS SHOW WEAK
INSTABILITY. THE HRRR AND 00Z SPC WRF SHOW ISOLATED COVERAGE.
SLIGHT CHANCE POPS MAINLY SOUTHERN FORECAST AREA STILL SEEMS
APPROPRIATE. HIGH TEMPERATURES ARE FORECAST NEAR NORMAL...IN THE
UPPER 80S.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
MAY STILL HAVE AN ISOLATED LINGERING SHOWER/STORM UNTIL
MIDNIGHT...THEN DRY FOR ALL AREAS THE REMAINDER OF THE NIGHT.
MOISTURE WILL BEGIN TO INCREASE ACROSS THE SOUTHERN PORTIONS OF
THE CWA SATURDAY. THIS MOISTURE INCREASE IS EXPECTED TO REMAIN
CONFINED TO THE SOUTH THROUGH THE DAY...WITH NORTHERN COUNTIES
STILL HAVING DRIER AIR IN PLACE. THIS WOULD LEAD TO THE BEST RAIN
CHANCES BEING ACROSS THE SOUTH AND SOUTH-CENTRAL COUNTIES ON
SATURDAY...WITH THE NORTHERN COUNTIES DRY OR ONLY HAVING AN
ISOLATED SHOWER/STORM. TEMPERATURES IN THE MIDDLE TO UPPER 60S
TONIGHT WITH THE DRIER AIR. SATURDAY WILL SEE HIGHS IN THE UPPER
80S. LOWS SATURDAY NIGHT MODERATE SLIGHTLY WITH THE MOISTURE
INCREASE...WITH READINGS AROUND 70.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
UPPER TROUGH WILL REMAIN TO OUR WEST WITH UPPER RIDGE REMAINING
CENTERED TO OUR E AND SE. THIS WILL CONTINUE TO DRAW MOISTURE
NORTHWARD INTO OUR REGION SUNDAY. EXPECTING TO HAVE CONTINUED
DIURNAL CONVECTION SUNDAY INTO TUESDAY WITH THIS PATTERN.
EARLY TO MID NEXT WEEK...MODELS MAINTAIN WEAK UPPER TROUGH TO OUR
WEST AND UPPER RIDGE TO OUR E AND SE. MAIN CONCERN FOR THIS TIME
PERIOD WILL BE THE EVENTUAL TRACK AND STRENGTH OF TROPICAL
CYCLONE ERIKA AS IT APPROACHES THE ATLANTIC COASTLINE. LATEST
OFFICIAL FORECAST FROM NHC BRINGS IT NW TOWARDS THE FLORIDA EAST
COAST BY LATE SUNDAY INTO EARLY TUESDAY...STRENGTHENING IT TO A
LOW END HURRICANE. THERE CONTINUES TO BE LITTLE RUN TO RUN
CONSISTENCE WITH THE LONGER RANGE MODELS...ESPECIALLY WITH THE
TRACK...AND WITH THE LARGE MODEL SPREAD...CONFIDENCE IS LOW OUT IN
THE LONG TERM. PLEASE SEE THE NHC FORECAST FOR LATEST DISCUSSION
AND TRACK OF ERIKA. FOR NOW...DUE TO UNCERTAINTIES REGARDING IMPACT
FOR OUR AREA...WILL CONTINUE TO MAINTAIN CHANCE POPS.
&&
.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
NOCTURNAL COOLING AND LOW-LEVEL MOISTURE SHOULD LEAD TO STRATUS
AND FOG EARLY THIS MORNING. STRATUS IS FAVORED INSTEAD OF FOG
BECAUSE OF WIND. HEATING AND MIXING SHOULD BRING IMPROVEMENT
DURING THE DAY. LEANED TOWARD THE SLOWER NAM MOS TIMING BECAUSE
THIS GUIDANCE DID BETTER THE PREVIOUS DAY. ANOTHER SLIGHT CHANCE
OF DIURNAL CONVECTION AT THE TERMINALS THIS AFTERNOON/EVENING...ALTHOUGH
CONFIDENCE REMAINS TOO LOW TO INCLUDE IN CURRENT ISSUANCE. WINDS
WILL CONTINUE OUT OF THE NORTHEAST/EAST TODAY AT 10 KNOTS OR
LESS.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE IN MAINLY EARLY
MORNING FOG AND STRATUS PLUS AFTERNOON AND EVENING SCATTERED
THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
99
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
312 AM EDT FRI AUG 28 2015
.SYNOPSIS...
A FRONTAL BOUNDARY WILL REMAIN STALLED NEAR THE COAST TODAY. A
LARGE AREA OF SURFACE HIGH PRESSURE CENTERED OVER THE GREAT LAKES
REGION WILL SLIDE EAST TO THE ATLANTIC COAST FOR THE WEEKEND.
INCREASING ATMOSPHERIC MOISTURE WILL DRIFT NORTH INTO OUR REGION
THIS WEEKEND. TROPICAL CYCLONE ERIKA IS EXPECTED TO APPROACH
SOUTHERN FLORIDA ON SUNDAY. REFER TO THE LATEST ADVISORY ON ERIKA
ISSUED BY THE NATIONAL HURRICANE CENTER.
&&
.NEAR TERM /THROUGH TODAY/...
EARLY THIS MORNING...LOW CLOUDS HAVE BEGUN TO DEVELOP EARLY THIS
MORNING...ESPECIALLY ACROSS THE WESTERN HALF OF THE FORECAST AREA
GIVEN DRY AIR ALOFT. OVERNIGHT LOWS WILL ONCE AGAIN RANGE FROM THE
MID 60S TO THE LOWER 70S.
TODAY...AN UPPER LEVEL TROUGH EXTENDING FROM THE OHIO RIVER
VALLEY TO THE GULF OF MEXICO WILL WEAKEN AND LIFT NORTH TODAY. THE
FRONTAL BOUNDARY IS EXPECTED TO REMAIN STALLED NEAR THE COAST.
SURFACE HIGH PRESSURE WILL CONTINUE TO RIDGE IN FROM THE NORTH
PRODUCING NORTHEASTERLY/EASTERLY FLOW. MODELS SHOW A STRONG
GRADIENT IN PRECIPITABLE WATER FROM NORTH TO SOUTH ACROSS THE
AREA WITH THE BEST MOISTURE SOUTH. MODEL SOUNDINGS SHOW WEAK
INSTABILITY. THE HRRR AND 00Z SPC WRF SHOW ISOLATED COVERAGE.
SLIGHT CHANCE POPS MAINLY SOUTHERN FORECAST AREA STILL SEEMS
APPROPRIATE. HIGH TEMPERATURES ARE FORECAST NEAR NORMAL...IN THE
UPPER 80S.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
MODELS CONTINUE TO INDICATE MAIN UPPER TROUGH JUST TO OUR WEST
WILL GRADUALLY WEAKEN AND LIFT NORTH THROUGH THE PERIOD...LEAVING
BEHIND A WEAK CUT OFF LOW NEAR THE NORTHERN GULF OF MEXICO...WHILE
UPPER RIDGE OVER THE WESTERN ATLANTIC BEGINS TO BUILD WESTWARD
TOWARDS THE SE COAST. THIS IS EXPECTED TO LEAD TO BAND OF BETTER
MOISTURE AND OLD SURFACE BOUNDARIES CURRENTLY TO OUR SOUTH TO
GRADUALLY DRIFT NORTH INTO OUR REGION SATURDAY. MAIN DIFFERENCE
WITH LATEST MODEL RUNS IS A LITTLE SLOWER TIMING WITH MOISTURE
INCREASE...AND MAINLY RELEGATING BEST MOISTURE TO THE S AND W
FA...AND MAINTAINING RELATIVELY DRY AIR OVER THE N FA...AS SURFACE
HIGH REMAINS ANCHORED OVER THE MID ATLANTIC RIDGING INTO THE
WESTERN CAROLINAS.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
UPPER TROUGH WILL REMAIN TO OUR WEST WITH UPPER RIDGE REMAINING
CENTERED TO OUR E AND SE. THIS WILL CONTINUE TO DRAW MOISTURE
NORTHWARD INTO OUR REGION SUNDAY. SO...WILL MAINTAIN TREND TOWARDS
INCREASING POPS.
EARLY TO MID NEXT WEEK...MODELS MAINTAIN WEAK UPPER TROUGH TO OUR
WEST AND UPPER RIDGE TO OUR E AND SE. MAIN CONCERN FOR THIS TIME
PERIOD WILL BE TROPICAL CYCLONE ERIKA. LATEST OFFICIAL FORECAST
FROM NHC BRINGS IT NW TOWARDS THE FLORIDA EAST COAST BY LATE
SUNDAY INTO EARLY TUESDAY...STRENGTHENING IT TO A LOW END
HURRICANE. GENERAL MODEL CONSENSUS HAS IT DRIFTING TO THE NORTH OR
NE THEREAFTER. FOR NOW...DUE TO UNCERTAINTIES REGARDING IMPACT
FOR OUR FA...WILL CONTINUE TO MAINTAIN CHANCE POPS.
&&
.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
NOCTURNAL COOLING AND LOW-LEVEL MOISTURE SHOULD LEAD TO STRATUS
AND FOG EARLY THIS MORNING. STRATUS IS FAVORED INSTEAD OF FOG
BECAUSE OF WIND. HEATING AND MIXING SHOULD BRING IMPROVEMENT
DURING THE DAY. LEANED TOWARD THE SLOWER NAM MOS TIMING BECAUSE
THIS GUIDANCE DID BETTER THE PREVIOUS DAY. ANOTHER SLIGHT CHANCE
OF DIURNAL CONVECTION AT THE TERMINALS THIS AFTERNOON/EVENING...ALTHOUGH
CONFIDENCE REMAINS TOO LOW TO INCLUDE IN CURRENT ISSUANCE. WINDS
WILL CONTINUE OUT OF THE NORTHEAST/EAST TODAY AT 10 KNOTS OR
LESS.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE IN MAINLY EARLY
MORNING FOG AND STRATUS PLUS AFTERNOON AND EVENING SCATTERED
THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
323 AM CDT FRI AUG 28 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 249 AM CDT FRI AUG 28 2015
Early this morning an upper trough extended from northwest IA
southwest across central KS. Ascent ahead of the trough axis
combined with isentropic lift above 850mb level was causing numerous
showers and isolated thunderstorms across the western and northern
counties of the CWA. MUCAPES were only around 500 J/KG, thus the
elevated thunderstorms will remain rather weak through the morning
hours. The scattered to numerous showers along with isolated
elevated thunderstorms will continue to move east across northeast
and east central KS through the morning hours. We may see a break in
the showers and thunderstorms during the early afternoon hours as
the stronger isentropic lift shifts northeast into northern MO and
eastern IA.
A second H5 trough will dig southeast across eastern KS later this
afternoon along with a surface cold front located across central NE
and northwest KS. As the surface front pushes southeast across
northeast and east central KS, scattered showers and thunderstorms
will develop along the surface front. There may even be some post
frontal showers and thunderstorms due to the stronger ascent ahead
of the H5 trough digging southeast on the back side of a developing
closed upper low across northeast IA and southeast MN.
If we see some insolation then MLCAPES may increase to around 1500
J/KG. The sfc to 6 KM effective shear will remain rather weak, under
20 KTS, through the day as the low-level flow veer to the southwest
ahead of the surface cold front. There could be a few strong storms
that may produce small hail and gusty winds if the atmosphere
destabilizes ahead of the surface front. The surface front and H5
trough will pass southeast of the CWA after 6Z. There could be a few
lingering showers northwest of the front across the extreme southeast
counties through the early morning hours of Saturday but these
showers should shift southeast of the CWA before 12Z SAT.
Highs Today will be dependent on the degree of insolation. If we
remain cloudy through the day then highs may only reach the upper
70s to lower 80s. Areas that see more insolation may reach the mid
80s. Tonight lows will drop into the lower to mid 60s.
.LONG TERM...(Saturday THROUGH Thursday)
ISSUED AT 249 AM CDT FRI AUG 28 2015
Saturday...Weak shortwave trough drifts slowly off to the
southeast, ending precip chances in east central KS, although some
clouds could linger in that area through Saturday night.
Saturday night through Sunday night...Upper ridge builds east
during this time as previously mentioned remnant vort max weakens
over the Ozark area. Would expect dry conditions through this time
period...although isolated showers could form in southeast KS,
with a small chance they could affect areas mainly south of I35.
Monday through Tuesday night...Upper ridge is flattened by a
shortwave trough that moves from the central Rockies to the Upper
Midwest. Main dynamics/lift with this trough should be to our
north but both GFS and ECMWF do develop QPF in north central/far
northeast KS Tuesday night. Have added low POPS for that area
overnight.
Wednesday through Thursday...Behind this trough, persistent low-
level warm advection helps build upper ridge back over the eastern
Plains into the Upper Midwest, with seasonably warm max
temperatures expected to be in the lower 90s each day.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z Friday NIGHT)
ISSUED AT 1152 PM CDT THU AUG 27 2015
Area of showers and thunderstorms over north central KS late this
evening should move east through northeast Kansas through Friday
morning. Preferred the latest HRRR and 00Z 12KM NAM concerning
the movement of the precipitation. Given the limited instability,
precipitation will likely be showers with embedded thunderstorms
so forecasted showers at KTOP/KFOE. 00z NAM sounding for Friday
afternoon suggest surface based thunderstorms are possible as weak
boundary approaches. Kept VCTS for this possibility. Otherwise,
VFR conditions.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Gargan
LONG TERM...GDP
AVIATION...Johnson
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1200 AM CDT FRI AUG 28 2015
...Update to aviation forecast discussion...
.SHORT TERM...(THIS EVENING THROUGH Friday)
ISSUED AT 242 PM CDT THU AUG 27 2015
Thunderstorm chances and degree of strength remain the challenges
in the short term. Morning convection out east provided a robust
outflow boundary that continues to reinforce in the east and
advance into south central Kansas at this hour. Clouds have also
lessened instability to the east, while elevated weak echoes have
started to develop out ahead of the surface low in southwest
nebraska into NW Kansas. True surface front appears to be just
through Goodland with dryline extending to the SSE, and a weak
prefrontal trof having become commingled with the outflow across
the central part of the state. Clouds and outflow has likely
impacted surface based instability, although lapse rates aloft
remain steep above the warm nose.
For the evening hours, expect weak echoes to continue to develop
over Central Kansas and move eastward with most activity remaining
east of Manhattan through midnight. CAPE dissipates quickly as the
evening progresses, and wind shear remains on the low end around
30kts 0-6km. NAM soundings suggest some help from LLJ in getting
storms started overnight, and along with the weakly defined front
moving through the area, should bring storms through overnight
and into Friday afternoon. A few of the storms could be severe,
but think SPC outlook keeping marginal threat in the northwest
part of our area is a good representation. Lows tonight with
clouds and precip remain around 70, with highs tomorrow in the low
to middle 80s.
.LONG TERM...(Friday NIGHT THROUGH Thursday)
ISSUED AT 242 PM CDT THU AUG 27 2015
Friday night through Sunday
By Friday evening, sfc frontal boundary is similar with guidance
positioning southwest to northeast over east central areas of the
CWA. While subsidence increases behind the trough over north central
areas, it is possible scattered convection could continue to develop
along the boundary. Weak instability above 850 mb and 0-6 km bulk
shear up to 20 kts precludes widespread severe storms from
developing. Otherwise cloud cover will gradually clear behind the
wave Saturday morning with lows starting out in the upper 50s and
low 60s. Light cool advection from the north during the afternoon
keeps temps cooler than previous days in the 80s. High pressure
continues to build in through Sunday as highs gradually modify back
into the upper 80s and lower 90s for Sunday. No major changes were
made to this period.
Upper flow will become amplified with organized westerlies forecast
to remain displaced well NW of northeast Kansas. As a result...do
not expect any fronts to approach/pass through the area and any high
plains storms should remain west/northwest of the area given weak
flow.
In a nutshell, the extended looks dry for the most part and warm
with stubborn ridge expected to remain just east of the state
keeping any eastward progression of the west coast trough limited.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z Friday NIGHT)
ISSUED AT 1152 PM CDT THU AUG 27 2015
Area of showers and thunderstorms over north central KS late this
evening should move east through northeast Kansas through Friday
morning. Preferred the latest HRRR and 00Z 12KM NAM concerning
the movement of the precipitation. Given the limited instability,
precipitation will likely be showers with embedded thunderstorms
so forecasted showers at KTOP/KFOE. 00z NAM sounding for Friday
afternoon suggest surface based thunderstorms are possible as weak
boundary approaches. Kept VCTS for this possibility. Otherwise,
VFR conditions.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...67
LONG TERM...Bowen/Omitt
AVIATION...Johnson
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
207 AM EDT FRI AUG 28 2015
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 411 PM EDT THU AUG 27 2015
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW WNW FLOW INTO THE UPPER
GREAT LAKES. RIDGE THAT EXTENDED FROM THE SRN ROCKIES TO SCNTRL
CANADA YESTERDAY IS WEAKENING DUE TO SHORTWAVE ENERGY TRACKING FROM
NRN ALBERTA TO NRN MANITOBA AND ANOTHER SHORTWAVE MOVING FROM WY
INTO THE WRN PLAINS. THAT SHORTWAVE WILL BEGIN TO BECOME A FCST
ISSUE HERE ON FRI. AFTER MORNING FOG...THE DAY HAS TURNED MOSTLY
SUNNY...THOUGH AN ELEVATED SMOKE LAYER HAS LEFT THE SKY WITH A HAZY
APPEARANCE. TEMPS HAVE REBOUNDED INTO THE MID 60S TO LWR 70S.
QUIET WEATHER WILL CONTINUE TONIGHT AS DRY AIR IN A RELATIVE SENSE
DOMINATES MOST OF THE COLUMN. LIGHT SOUTHERLY WINDS AND AN INCREASE
IN PRECIPITABLE WATER WILL RESULT IN A WARMER NIGHT THAN LAST NIGHT.
EXPECT MINS MOSTLY IN THE 50S...THOUGH DOWNSLOPE AREAS NEAR LAKE
SUPERIOR MAY NOT FALL BLO 60F.
ON FRI...THE WRN PLAINS SHORTWAVE WILL MOVE TO WI. BEST
WAA/ISENTROPIC ASCENT ASSOCIATED WITH FEATURE SHIFTS FROM NRN IA/SRN
MN INTO WI...SO BULK OF PCPN WILL PASS BY TO THE S OF HERE. THAT
AREA IS ALSO WHERE MODELS SHOW HEAVIEST PCPN. PCPN CHANCES WILL BE
MUCH MORE LIMITED TO THE N. WHILE HIGH RES WRF-ARW/NMM ARE LIKELY
TOO AGGRESSIVE IN SPREADING PCPN INTO SCNTRL UPPER MI FRI...MOST
MODELS DO BRING SOME PCPN INTO THE SCNTRL IN THE AFTN. WILL PAINT
CHC POPS OVER THE FAR SCNTRL. DEPENDING ON CLOUD COVER/DAYTIME
HEATING...THE GFS AND ESPECIALLY NAM BUILD A LITTLE BIT OF
INSTABILITY PER MLCAPES FARTHER N. HAVE INCLUDED SCHC POPS FOR -SHRA
IN THE EVENT A FEW -SHRA MANAGE TO POP IN THE AFTN.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 301 PM EDT THU AUG 27 2015
PLENTY OF UNCERTAINTY IN THE FIRST 24 HOURS OF THE LONG TERM...FRI
NIGHT AND SAT. A SHORTWAVE IS SET TO MOVE OUT OF THE CENTRAL PLAINS
AND MOVE THROUGH OR NEAR THE REGION DURING THIS TIME. THE 00Z/27
ECMWF IS DEEPEST AND FARTHEST NORTH WITH THE SHORTWAVE...WITH RAIN
OVER MOST OF THE CWA. THE 12Z/27 GFS IS QUITE A BIT WEAKER AND
FARTHER S...KEEPING MOST OF THE CWA DRY. THE 12Z/27 GEM AND 12Z/27
NAM MATCH CLOSER TO THE GFS...BUT DO BRING SOME PRECIP INTO THE SRN
CWA. WILL TEND TO FAVOR A GFS/NAM/GEM CONSENSUS GIVEN HOW MUCH OF AN
OUTLIER THE ECMWF IS. THIS RESULTS IN CHANCE POPS OVER SCENTRAL UPPER
MI FRI NIGHT AND SAT MORNING AND SLIGHT CHANCE POPS ELSEWHERE. DRY
CONDITIONS EXPECTED BY 00Z SUN.
MODELS CONTINUE TO BUILD AN UPPER RIDGE OVER THE REGION FROM SUN
THROUGH THE REST OF NEXT WEEK. RAIN CHANCES WILL BE MINIMAL...BUT
COULD SEE SOME CONVECTION WED OR THU IF SHORTWAVE ENERGY CAN ROUND
THE TOP OF THE RIDGE...BUT CHANCES ARE LOW. THE AIRMASS WILL BE ON
THE RISE...HOVERING AROUND 20C FROM LATE MON THROUGH THE REST OF THE
WEEK. THIS RESULTS IN TEMPS BEING 10 OR MORE DEGREES ABOVE NORMAL
FROM MON ON.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 207 AM EDT FRI AUG 28 2015
RELATIVELY DRY AIR MASS OVER THE AREA SHOULD ENSURE VFR CONDITIONS
CONTINUE THRU THIS FCST PERIOD AT KIWD/KCMX/KSAW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 411 PM EDT THU AUG 27 2015
A GENERALLY WEAK PRES GRADIENT WILL DOMINATE THE UPPER LAKES INTO
EARLY NEXT WEEK. ON MOST DAYS...WINDS WILL BE UNDER 15KT...BUT THERE
WILL BE SOME PERIODS WHERE GUSTS WILL GET INTO THE 15-20KT RANGE.
LOOKS LIKE THE LIGHTEST WINDS WILL OCCUR OVER THE WEEKEND WITH HIGH
PRES RIDGE MORE FIRMLY IN CONTROL.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...07
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
305 AM CDT FRI AUG 28 2015
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 305 AM CDT FRI AUG 28 2015
PCPN CHANCES TODAY AND THEN TEMPERATURES THE NEXT FEW DAYS WILL BE
THE MAIN FORECAST CONCERNS.
FAIRLY WIDESPREAD AREA OF SHRA AND TSRA WILL CONTINUE TO MOVE EAST
THIS MORNING...ASSOCIATED WITH SHORTWAVE TROUGH MOVING THROUGH THE
REGION. WATER VAPOR SATELLITE IMAGERY LOOP IN COMBINATION WITH
RECENT 500 MB RUC MODEL INITIALIZATIONS SHOWED A FAIRLY STRONG
WAVE FOR THIS TIME OF YEAR. 12 HOUR HEIGHT FALLS AT 500 MB WERE UP
TO ABOUT 50 METERS. ATMOSPHERE WAS ALSO QUITE MOIST. 700 MB
DEWPOINTS OF 4-8 DEGREES C WERE NOTED FROM THE DESERT SW UP INTO
WRN KS AND SWRN NE AT 00Z LAST EVENING...AND FORECAST SOUNDINGS
SUGGEST PW VALUES ARE AROUND 2 INCHES OR MORE EARLY THIS MORNING.
ALTHOUGH THE STRONGEST AREA OF LIFT AND HIGHEST MOISTURE WILL BE
SHIFTING EAST OF THE LOCAL AREA...KEPT SOME POPS GOING MUCH OF THE
DAY. A WEAKER AREA OF LIFT SHOULD SPREAD SEWD OVER THE REGION AND
FORECAST SOUNDINGS STILL SHOW SOME INSTABILITY. WILL KEEP RAIN
CHANCES MAINLY AT 20-30 PERCENT AFTER EARLY MORNING ACTIVITY ENDS.
RECENT HRRR RUNS AND EVEN THE 00Z NAM SUGGEST PREVIOUS SCENARIO...
WITH AT LEAST ISOLD SHRA/TSRA POSSIBLE.
LINGERED A SLIGHT CHANCE OF TSRA IN OUR FAR SERN ZONES EARLY THIS
EVENING...THEN IT SHOULD BE MAINLY DRY THROUGH SUNDAY. KEPT SOME
MENTION OF FOG TONIGHT WITH LIGHT WINDS AND BOTH GFS MOS AND NAM
MOS SUGGESTING AT LEAST PATCHY FOG LATE TONIGHT INTO SAT MORNING.
DID NOT MENTION FOG SATURDAY NIGHT...BUT SFC RIDGE AXIS WILL BE
CLOSE TO THE AREA AND WILL NEED TO MONITOR. RETURN FLOW WITH S/SE
SFC WINDS SHOULD THEN STRENGTHEN SUNDAY.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 305 AM CDT FRI AUG 28 2015
MID LEVEL RIDGE EXTENDING FROM NWRN MEXICO UP INTO THE CNTRL
PLAINS AND A TROUGH FROM WRN CANADA INTO THE NWRN UNITED STATES
WILL BE THE MAIN FEATURES AT THE START OF THIS PERIOD. RIDGE WILL
SLIDE SLOWLY SEWD AS THE TROUGH TO THE NORTHWEST DIGS. WEAK RIPPLES
MOVING NEWD THROUGH THE REGION COULD BRING SOME TSRA...WITH BEST
CHANCES BEING TUE NIGHT AND AGAIN THU NIGHT.
TEMPERATURES SHOULD BE AT OR ABOVE NORMAL OVER THE AREA FOR MOST
OR ALL OF NEXT WEEK.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1127 PM CDT THU AUG 27 2015
RADAR MOSAIC TREND THE LAST FEW HOURS REVEALING THAT AREAL COVERAGE
INCREASE MAINLY OVER NERN AND EAST-CENTRAL NEB THIS MORNING REVOLVING
AROUND SFC LOW SITUATED IN SERN NEB. AT THIS POINT EXPECT ACTIVITY
TO CONTINUE AT ALL TERMINALS THRU AT LEAST 10Z THIS MORNING. AFT
10Z...CONDITIONS AT KOFK DETERIORATE TO MVFR/IFR TERRITORY THRU ABOUT
MID MORNING. AS FOR KOMA/KLNK...HAVE TEMPO GROUPS IN PLACE TO TSRA
ACTIVITY BTWN 06Z-10Z. THEREAFTER...VFR CONDITIONS SHOULD PREVAIL
AT BOTH TAF SITES.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...DEE
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1249 AM EDT FRI AUG 28 2015
.SYNOPSIS...
A STATIONARY FRONT OFF THE COAST WILL DRIFT SLOWLY EAST THROUGH
THE WEEKEND AS WEAK HIGH PRESSURE BUILDS INTO THE AREA FROM THE
NORTH. TROPICAL CYCLONE ERIKA IS FORECAST TO BE IN THE VICINITY OF
THE SOUTHEAST COAST EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1245 AM FRIDAY...HAVE ADJUSTED POPS DOWN AS MOST OF THE
ACTIVITY IS NOW OFFSHORE. WILL KEEP JUST A SLIGHT CHANCE OF
PRECIPITATION ALONG THE COAST OVERNIGHT. REST OF FORECAST IN
PRETTY GOOD SHAPE. MID/HIGH CLOUDS WILL CONTINUE TO PREVAIL
OVERNIGHT WITH LOW TEMPERATURE FORECAST IN THE MID 60S INLAND TO
AROUND 70 LOOKING GOOD.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 AM SATURDAY/...
AS OF 240 PM THURSDAY...DEEPER MOISTURE WILL GRAD MOVE FURTHER E
FRI AS HIGH PRES BUILDS CLOSER AND THE FRONT/LOW OFFSHORE MOVES
FURTHER E. EXPECT DRY CONDITIONS INLAND WITH A SLIGHT CHC TO CHC
POP IMD CST...ESPCLY EARLY. WITH MORE SUN INLAND SHLD SEE HIGHS
AROUND 85 WITH LOWER 80S CST.
&&
.LONG TERM /SATURDAY THROUGH FRIDAY/...
AS OF 335 PM THURSDAY...WEAK ZONAL FLOW DEVELOPS FRIDAY WITH THE
UPPER RIDGE OVER BERMUDA BUILDING WEST TOWARDS THE SOUTHEASTERN
STATES. AT THE SURFACE, A WEAK FRONT WILL REMAIN STALL OFF THE NC
COAST THROUGH SATURDAY.
LITTLE CHANGE IN FORECAST REASONING BASED ON 12Z GUIDANCE THROUGH
THE PERIOD. THE FRONTAL BOUNDARY AND DEEPEST MOISTURE REMAINS
STALLED OFFSHORE THROUGH FRIDAY NIGHT AND WILL MAINTAIN DRY
CONDITIONS INLAND TO SLIGHT CHANCE POPS FOR COASTAL SECTIONS.
THE UPPER RIDGE ACROSS THE WESTERN ATLANTIC BUILDS WEST INTO THE
SOUTHEAST FRIDAY THROUGH EARLY NEXT WEEK WHILE A ROBUST NORTHERN
STREAM SHORTWAVE MOVES ACROSS THE MIDWEST INTO THE WEEKEND. A BROAD
SHORTWAVE WILL LIFT NORTHEAST AROUND THE WESTERN PERIPHERY OF THE
UPPER RIDGE SATURDAY NIGHT THROUGH SUNDAY, THOUGH WILL REMAIN FAR
ENOUGH NORTH AND WEST OF THE REGION TO HAVE LITTLE IMPACT. AT THE
SURFACE, HIGH PRESSURE WILL SHIFT OFF THE MID-ATLANTIC COAST LATE
FRIDAY AND RIDGE SOUTHWEST INTO EASTERN NC FRIDAY NIGHT INTO
SATURDAY, THEN TRANSITION OFFSHORE WITH THE PIEDMONT TROUGH
DEVELOPING SUNDAY THROUGH TUESDAY. WILL MAINTAIN SLIGHT CHANCE
POPS FOR DIURNALLY DRIVEN, MAINLY ISOLATED, SHOWER/THUNDERSTORM
PATTERN THROUGH THE WEEKEND AND INTO TUESDAY. TEMPERATURES WILL
BE NEAR OR A FEW DEGREES ABOVE CLIMATOLOGY FOR LATE AUGUST.
THE FORECAST FOR WEDNESDAY AND THURSDAY, DAY 7/8, IS PARTICULARLY
TRICKY DUE TO THE UNCERTAINTY IN ANY TROPICAL IMPACTS FROM
TROPICAL STORM ERIKA, CURRENTLY SOUTHEAST OF PUERTO RICO. WILL
HEDGE TOWARDS A MODEL BLEND FOR THIS PERIOD WITH SLIGHT CHANCE
POPS WEDNESDAY INCREASING TO CHANCE POPS THURSDAY, AS SURFACE FLOW
SHIFTS SOUTHEASTERLY AND ABUNDANT MOISTURE OVERSPREADS EASTERN NC.
THE FOCUS WILL BE ON THE TROPICS THIS WEEKEND AS THE NATIONAL
HURRICANE CENTER HAS TROPICAL STORM ERIKA FORECAST TO MOVE INTO
THE BAHAMAS. SIGNIFICANT UNCERTAINTY CONTINUES WITH REGARDS TO
THE STRENGTH AND TRACK OF THE SYSTEM BEYOND DAY 3 WITH POOR RUN TO
RUN CONSISTENCY IN THE MODELS, THUS IT IS TOO SOON TO SPECULATE AT
THIS TIME WHAT IMPACTS MAY BE FELT ACROSS THE REGION NEXT WEEK.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
SHORT TERM /THROUGH 06Z SATURDAY/...
AS OF 1245 AM FRIDAY...HAVE CONTINUED TREND OF VFR FORECAST
THROUGH THE PERIOD. MID TO HIGH CLOUDS WILL PREVAIL OVERNIGHT AND
WITH WEAK BOUNDARY LAYER MIXING DO NOT EXPECT MUCH IN THE WAY OF
FOG OR STRATUS FORMATION OVERNIGHT. DRIER AIR ADVECTS INTO THE
REGION FOR FRIDAY INTO FRIDAY NIGHT WITH VFR CONDITIONS
PREVAILING.
LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 340 PM THURSDAY...PREDOMINANT VFR CONDITIONS EXPECTED
THROUGH TUESDAY WITH ONLY ISOLATED, MAINLY DIURNALLY DRIVEN
SHRA/TSRA.
&&
.MARINE...
SHORT TERM /THROUGH FRI/...
AS OF 1245 AM FRIDAY...GUSTY NORTHEAST WINDS OVER THE PAMLICO
SOUND AND SOME OF THE CENTRAL AND NORTHERN WATERS. THE HRRR AND
RUC ARE PICKING UP WELL ON THESE WINDS AND HAVE USED A BLEND OF
THESE WIND FIELDS FOR THE VERY NEAR TERM. SEAS CONTINUE IN THE 3
TO 5 FEET RANGE AND THIS SHOULD PERSIST OVERNIGHT. ON FRI THE
HIGH BUILDS JUST TO THE N AS THE LOW/FRONT DRIFTS FURTHER E. THIS
SHLD LEAD TO NE WINDS DIMINISHING TO 10 TO 15 KTS. THE PERSISTENT
FETCH WILL KEEP SEAS 3 TO 5 FEET...HIGHEST OUTER WATERS.
LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 340 PM THURSDAY...THE HIGH WILL SHIFT OFF THE MID-ATLANTIC
COAST FRIDAY NIGHT INTO SATURDAY WITH WINDS AROUND 15 KT OR LESS
SATURDAY, DIMINISHING TO 10 KT OR LESS BY SUNDAY. WIND DIRECTION
WILL GENERALLY BE NORTHEAST SATURDAY AND SUNDAY, VEERING SOUTHEAST
SUNDAY NIGHT THEN SOUTH MONDAY INTO TUESDAY. WIND SPEEDS WILL
BECOME LESS THAN 10 KT SUNDAY NIGHT THROUGH MONDAY NIGHT DUE TO
WEAK PRESSURE GRADIENT ACROSS THE EASTERN NC COASTAL WATERS. SEAS
WILL RANGE 2-3 FT THROUGH THE LONG TERM WITH SOME 4 FT SEAS FOR
THE OUTER CENTRAL WATERS. LOCAL SWAN/NWPS PERFORMING BETTER IN
NORTHEAST WIND/SWELL CONDITIONS SATURDAY, THEN A GENERAL BLEND
WITH WAVEWATCH FOR THE MEDIUM RANGE. MARINE INTERESTS SHOULD
CONTINUE TO MONITOR THE DEVELOPMENT OF TROPICAL STORM ERIKA OVER
THE WEEKEND, CURRENTLY LOCATED SOUTHEAST OF PUERTO RICO.
SIGNIFICANT UNCERTAINTY REMAINS WITH REGARDS TO FORECAST TRACK AND
INTENSITY BEYOND DAY 3.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...RF
NEAR TERM...CTC
SHORT TERM...RF
LONG TERM...DAG
AVIATION...CTC/DAG
MARINE...CTC/JBM/DAG/LEP
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
331 AM CDT FRI AUG 28 2015
.SHORT TERM...
UA RIDGE CENTERED TO OUR WEST HAS FLATTENED OUT A BIT THUS RESULTING
IN WNW FLOW ALOFT PREVAILING ACROSS THE SOUTHERN PLAINS. THIS DE-
AMPLIFICATION OF THE UA RIDGE IS DUE TO AN UA SHORTWAVE THAT HAS
TRACKED ENE FROM THE ROCKIES TO ACROSS THE CENTRAL/NORTHERN PLAINS
EARLY THIS MORNING. ITS ASSOCIATED COLD FRONT HAS BEEN SAGGING SWRD
ACROSS THE TX PANHANDLE AND HAS MOVED SOUTH OF KAMA AS OF 08Z.
ALTHOUGH THE BEST LARGE SCALE ASCENT IS WELL NORTH OF THE REGION...
SCATTERED CONVECTION HAS MANAGED TO DEVELOP IN THE WAKE OF THE
FRONT ACROSS THE TX PANHANDLE...COURTESY OF ADEQUATE FRONTOGENETICAL
FORCING. NOT ONLY ARE MODEL SOLUTIONS HAVING DIFFICULTY IN SHOWING
CONSENSUS WRT TO THE TIMING OF THE FRONT /IMPINGING ON THE NRN
ZONES ANYWHERE FROM 12-18Z/ BUT ARE ALSO HAVING DIFFICULTY IN THE
SPATIAL EXTENT OF PRECIP...THUS MAKING IT HARD TO HANG YOUR HAT ON
ANY ONE PARTICULAR SOLUTION. NONETHELESS...IF THE CURRENT SPEED OF
THE FRONT DOES NOT SLOW DOWN MUCH...IT APPEARS THAT THE FRONT WILL
MOVE ACROSS THE NRN ZONES AN HOUR OR SO BEFORE SUNRISE /AS HINTED
AT BY THE RAP SOLUTION/ AND THEREFORE PROGGED TO GET HUNG UP DURING
THE DAYTIME /ORIENTED FROM SW TO NE/...HENCE NOT QUITE CLEARING THE
LOW ROLLING PLAINS. SOLUTIONS DO EXHIBIT PRECIP ORIENTED FROM THE
SWRN ZONES TO THE NERN ZONES ALONG THE FRONT...THOUGH AS STATE
EARLIER...SOME SOLUTIONS ARE A BIT MORE BULLISH IN ITS SPATIAL
EXTENT AND QPF AMOUNTS. WILL THEREFORE HOLD ON TO BEST POPS BEING
SHOWN FROM SW TO NE...WITH LOWEST POPS ACROSS THE LOW ROLLING
PLAINS THROUGHOUT THE SHORT TERM PERIOD.
STEEPENING LAPSE RATES THIS AFTN COUPLED WITH DAYTIME DESTABILIZATION
MAY RESULT IN A FEW STORMS GENERATING BRIEF WIND GUSTS...BUT SEVERE
POTENTIAL APPEARS LOW GIVEN BEST UL SUPPORT WILL BE NORTH OF THE
REGION.
BEING THAT THE COLD FRONT IS NOT TERRIBLY STRONG /AS 850 MB TEMPS DO
NOT DROP TERRIBLY LOW/ IT WILL STILL BE A FEW DEGREES COOLER THAN
YESTERDAY WITH HIGHS RANGING FROM THE UPPER 80S ACROSS THE FAR SW TX
PANHANDLE TO THE UPPER 90S TO LOWER 100 DEGREE READINGS ACROSS THE
LOW ROLLING PLAINS. OVERNIGHT LOWS WILL BE IN THE 60S AND 70S.
.LONG TERM...
A FAIRLY QUIET PERIOD COMING UP. THE LONG WAVE UPPER AIR PATTERN
OVER THE CONUS WILL REMAIN GENERALLY THE SAME THROUGH NEXT WEEK
WITH A TROUGH OVER THE WEST AND RIDGING FROM THE SRN PLAINS TO THE
NORTHEAST. HOWEVER...WEAKNESSES IN THE RIDGE WILL LEAVE HEIGHTS
AND THICKNESSES OVER THE AREA OF A MAGNITUDE THAT SHOULD KEEP
TEMPERATURES FROM GETTING TOO FAR OVER SEASONAL NORMS. ONLY OTHER
ISSUE IS POTENTIAL FOR GENERALLY AFTN AND EVENING PRECIP IN THE
NWRN COUNTIES VCNTY OF SFC TROUGH AND LOW LEVEL INSTABILITY AXIS.
MONDAY AND TUESDAY WOULD BE FAVORED. CONFIDENCE REMAINS LOW ATTM
AND HAVE KEPT MENTION OUT ATTM.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 87 61 89 61 / 20 20 10 0
TULIA 90 62 91 61 / 30 20 10 0
PLAINVIEW 89 63 91 63 / 30 30 10 0
LEVELLAND 93 64 91 64 / 30 30 10 10
LUBBOCK 94 65 92 65 / 30 30 10 0
DENVER CITY 93 63 91 63 / 20 30 10 0
BROWNFIELD 94 65 92 65 / 20 30 10 0
CHILDRESS 96 69 96 68 / 30 20 10 0
SPUR 98 69 94 67 / 20 20 10 10
ASPERMONT 100 72 97 70 / 10 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
29/07
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
1000 AM EDT FRI AUG 28 2015
.Near Term [Through Today]...
The 12Z TAE sounding showed quite an unstable environment with
mid-level lapse rates of about 7 C/km and MUCAPE of over 2200
J/kg. This matches up well with the RUC forecast, which shows
SBCAPE increasing to 2000-2500 J/kg over the next few hours. This
morning`s sounding showed a PWAT of only 1.61", which is fairly
dry for us this time of year, but 10-15 knot 1000-700 mb flow will
help increase low level moisture through the day and is a
favorable seabreeze pattern for widespread coverage of
thunderstorms across the area. Local satellite and radar imagery
show storms already active across our eastern coastal waters and
making further inland progression than originally forecast this
morning, so bumped up PoPs a bit through the remainder of the
daylight hours. Lingering dry air in the mid-levels and moderate
instability could combine to produce an environment somewhat
favorable for downbursts. Isolated strong to severe storms will be
possible with gusty winds the main threat.
&&
.Prev Discussion [653 AM EDT]...
.Short Term [Tonight Through Sunday]...
An elongated area of +PV stretches from the Northeast, through the
central Gulf of Mexico this morning. By tonight this area will
split into two anomalies: a more progressive wave moving off the
Northeast coast and what will be a quasi-stationary wave over the
north-central Gulf. It won`t be until Saturday night through
Sunday that this wave lifts through the Southeast. At the surface,
ridging will prevail across much of the eastern half of the
country. Locally, the ridge will be quite disturbed due to the
upper wave. Steering flow will generally have a south or
southeasterly component yielding a rather wet seabreeze regime
across the entire Tri-State area. Like the ridge, the seabreeze
will be far from ideal and enhanced by the upper level anomaly.
Thus, PoPs will be higher than normal through the weekend
(50-70%). High PoPs and plentiful cloud cover will keep afternoon
highs anywhere from the mid 80s to around 90 degrees. Overnight
lows will be in the middle 70s and not as pleasant as recent
nights as moisture surges back into the region.
.Long Term [Sunday Night Through Friday]...
The main feature in the extended range forecast will be what is
now Tropical Storm Erika. The eventual track will have a lot to do
with how Erika holds together as it moves across Hispaniola today.
The current track from NHC takes Erika south of the Bahamas before
curving it north along the immediate east coast of Florida. A
concerning trend in the dynamical models is a westward shift in
the track. Both the 00z GFS and ECMWF bring Erika into the eastern
Gulf, but diverge greatly with respect to timing. There has been a
lot of back and forth between the dynamical models and a great
deal of uncertainty still exists. But, the potential for at least
some sort of impacts locally from Erika appears to be increasing
over the past 24 hours. A track off the east coast of Florida will
bring minimal rain impacts to the Tri-State region, while a track
over the Peninsula will likely bring a great deal of rain over the
Suwannee Valley, and a track into the eastern Gulf would mean the
potential for both heavy rain and wind impacts area-wide. Due to
the uncertainty in this forecast and the latest trends, close
attention should be given to the forecast over the next couple of
days.
.Aviation...
[Through 12Z Saturday] VFR conditions are expected this morning,
with scattered to numerous showers and storms likely between 18Z
and 03Z. These showers and storms may affect any of the terminals
during that timeframe. This was handled in the TAFs with VCTS at
all of the terminals. Confidence was high enough in a particular
window where storms are more likely at VLD (21-01Z) to include a
TEMPO group with some gusty winds and IFR visibility. Similar
conditions (gusty winds and IFR visibility) will be possible in
any storms today, but confidence was not high enough in timing at
any of the other terminals to include additional TEMPO groups.
.Marine...
Light winds and low seas will prevail through the weekend. After
that, it will depend on Erika`s track. No matter the track, at
least a slight increase in winds and possibly seas should be
expected starting next week.
.Fire Weather...
An increase in low-level moisture will keep RH levels elevated and
allow rain chances to increase from today into the weekend.
.Hydrology...
With a transition to a wetter pattern beginning today, expect
average rainfall amounts on the order of 1-1.5" over the next
three days. This will have little impact on area rivers. Next
week, the potential for some very heavy rain exists depending on
Erika`s track. At this time, models suggest the possibility for
5-7" over a 48 hour period with Erika. Should the track shift
west, these amounts could spread into the southeast Big Bend and
south-central Georgia. Interests along the Suwannee River are
urged to pay close attention to rainfall forecasts over the next
few days.
&&
.Preliminary Point Temps/PoPs...
Tallahassee 91 75 86 73 90 / 50 40 60 30 50
Panama City 87 77 85 75 88 / 40 50 60 30 30
Dothan 91 73 85 70 89 / 50 40 60 30 30
Albany 91 73 86 71 89 / 50 40 60 40 40
Valdosta 91 74 87 73 90 / 50 40 60 30 50
Cross City 90 75 88 74 90 / 40 40 60 30 50
Apalachicola 89 77 85 76 87 / 50 60 60 40 30
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AL...NONE.
GM...NONE.
&&
$$
NEAR TERM...MOORE
SHORT TERM...HARRIGAN
LONG TERM...HARRIGAN
AVIATION...LAMERS
MARINE...HARRIGAN
FIRE WEATHER...LAMERS
HYDROLOGY...HARRIGAN
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
701 AM CDT FRI AUG 28 2015
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 305 AM CDT FRI AUG 28 2015
PCPN CHANCES TODAY AND THEN TEMPERATURES THE NEXT FEW DAYS WILL BE
THE MAIN FORECAST CONCERNS.
FAIRLY WIDESPREAD AREA OF SHRA AND TSRA WILL CONTINUE TO MOVE EAST
THIS MORNING...ASSOCIATED WITH SHORTWAVE TROUGH MOVING THROUGH THE
REGION. WATER VAPOR SATELLITE IMAGERY LOOP IN COMBINATION WITH
RECENT 500 MB RUC MODEL INITIALIZATIONS SHOWED A FAIRLY STRONG
WAVE FOR THIS TIME OF YEAR. 12 HOUR HEIGHT FALLS AT 500 MB WERE UP
TO ABOUT 50 METERS. ATMOSPHERE WAS ALSO QUITE MOIST. 700 MB
DEWPOINTS OF 4-8 DEGREES C WERE NOTED FROM THE DESERT SW UP INTO
WRN KS AND SWRN NE AT 00Z LAST EVENING...AND FORECAST SOUNDINGS
SUGGEST PW VALUES ARE AROUND 2 INCHES OR MORE EARLY THIS MORNING.
ALTHOUGH THE STRONGEST AREA OF LIFT AND HIGHEST MOISTURE WILL BE
SHIFTING EAST OF THE LOCAL AREA...KEPT SOME POPS GOING MUCH OF THE
DAY. A WEAKER AREA OF LIFT SHOULD SPREAD SEWD OVER THE REGION AND
FORECAST SOUNDINGS STILL SHOW SOME INSTABILITY. WILL KEEP RAIN
CHANCES MAINLY AT 20-30 PERCENT AFTER EARLY MORNING ACTIVITY ENDS.
RECENT HRRR RUNS AND EVEN THE 00Z NAM SUGGEST PREVIOUS SCENARIO...
WITH AT LEAST ISOLD SHRA/TSRA POSSIBLE.
LINGERED A SLIGHT CHANCE OF TSRA IN OUR FAR SERN ZONES EARLY THIS
EVENING...THEN IT SHOULD BE MAINLY DRY THROUGH SUNDAY. KEPT SOME
MENTION OF FOG TONIGHT WITH LIGHT WINDS AND BOTH GFS MOS AND NAM
MOS SUGGESTING AT LEAST PATCHY FOG LATE TONIGHT INTO SAT MORNING.
DID NOT MENTION FOG SATURDAY NIGHT...BUT SFC RIDGE AXIS WILL BE
CLOSE TO THE AREA AND WILL NEED TO MONITOR. RETURN FLOW WITH S/SE
SFC WINDS SHOULD THEN STRENGTHEN SUNDAY.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 305 AM CDT FRI AUG 28 2015
MID LEVEL RIDGE EXTENDING FROM NWRN MEXICO UP INTO THE CNTRL
PLAINS AND A TROUGH FROM WRN CANADA INTO THE NWRN UNITED STATES
WILL BE THE MAIN FEATURES AT THE START OF THIS PERIOD. RIDGE WILL
SLIDE SLOWLY SEWD AS THE TROUGH TO THE NORTHWEST DIGS. WEAK RIPPLES
MOVING NEWD THROUGH THE REGION COULD BRING SOME TSRA...WITH BEST
CHANCES BEING TUE NIGHT AND AGAIN THU NIGHT.
TEMPERATURES SHOULD BE AT OR ABOVE NORMAL OVER THE AREA FOR MOST
OR ALL OF NEXT WEEK.
&&
.AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 656 AM CDT FRI AUG 28 2015
VARIABLE CONDITIONS EXPECTED DURING THE PERIOD. IFR CIGS LOCATED
UNDER UPPER LOW OVER NORTHEAST NEBRASKA AND BEHIND COLD FRONT INTO
SOUTH CENTRAL NEBRASKA. LOWER CIGS SHOULD SPREAD EAST BEHIND FRONT
THROUGH 18Z WITH CIGS IMPROVING TO MVFR THROUGH 00Z. VFR
CONDITIONS THEN DEVELOP AFTER 00Z BUT A PERIOD OF LIFR CIGS AND
VSBY POSSIBLE AFTER 09Z AT ALL THREE SITES.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...FOBERT
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1015 AM EDT FRI AUG 28 2015
.SYNOPSIS...
A WEAK FRONT WILL MEANDER OFF THE THE COAST AS HIGH PRESSURE
SLOWLY BUILDS INTO THE CAROLINAS OVER THE WEEKEND. ERIKA IS
EXPECTED TO APPROACH THE BAHAMAS AND SOUTH FLORIDA LATE IN THE
WEEKEND TRACKING THROUGH FLORIDA INTO EARLY NEXT WEEK...AND
POSSIBLY REMAINING ON A MORE WESTWARD TRACK CLOSER TO THE GULF
COAST.
&&
.NEAR TERM /THROUGH TONIGHT/... AS OF 1015 AM FRIDAY...HAVE SLIGHTLY
CONTINUED THE DOWNWARD TREND IN SKY COVER AND TEMPTED TO DO THE SAME
WITH RAIN CHANCES. NEITHER THE 12KM WRF, HRRR, OR RUC BRING ANYTHING
MEASUREABLE ONSHORE. WILL WAIT ONE MORE CYCLE TO MONITOR CU
DEVELOPMENT AS WELL AS FORMATION OF NE RESULTANT SEABREEZE THAT MAY
GRAB AN OFFSHORE SHOWER AND FLING IT ASHORE. BEST CHANCE WOULD BE
BALD HEAD ISLAND/SOUTHPORT AREAS. PREVIOUS DISCUSSION FOLLOWS:
AS OF 650 AM FRIDAY...HAVE STAYED WITH A DRIER BIAS FOR THIS NEAR
TERM FORECAST...AND KEPT THE THREAT FOR LOW CHANCE POPS ACROSS THE
COASTAL COUNTIES WITH DIURNALLY DRIVEN CONVECTION THE MAIN
EMPHASIS FROM LATE THIS MORNING THRU EARLY THIS EVENING.
LATEST WATER VAPOR IMAGERY INDICATES A MUCH DRIER PICTURE COMPARED
THIS TIME YESTERDAY MORNING. PROGGED MODEL SOUNDINGS INDICATE DRY
AIR BETWEEN 350 MB AND 900 MB BECOMING MORE DOMINANT ACROSS THE FA
LATER THIS MORNING THRU TONIGHT AND INTO THE SHORT TERM PERIOD.
THE SOMEWHAT STALLED SFC BOUNDARY ORIENTED NE-SW AND PARALLEL TO
THE ILM CWA COASTLINE...WILL DRIFT SLIGHTLY FURTHER OFFSHORE THIS
PERIOD. THIS HAS ALREADY ALLOWED THE MODEST 1020+ SFC HIGH
BROADLY CENTERED OVER THE NE STATES AND MID-ATLANTIC TO RIDGE OR
NOSE SOUTH-SOUTHWESTWARD PUSHING DRIER AIR AND LOWER SFC DEWPOINTS
TO AND ACROSS THE ILM CWA. ALREADY OBSERVING WIDESPREAD 60S
DEWPOINTS ACROSS THE FA...ALL THE WAY TO THE IMMEDIATE COAST.
MODELS INDICATE POSSIBLY AROUND 60 THIS AFTN ACROSS THE
NORTHERNMOST PORTIONS OF THE FA THIS AFTN WHERE MIXING OF DRIER
AIR ALOFT TO THE SFC MAY OCCUR. WITH ALL THIS SAID...THE BEST
FORCING/LIFT FOR CONVECTION WILL INITIALLY START JUST ALONG AND
OFF THE IMMEDIATE COAST...AND SWITCH FURTHER EAST AND FURTHER OFF
THE MAINLAND AS THE BOUNDARY LAYER ASSOCIATED WITH THE STALLED SFC
FRONT DRIFTS EASTWARD.
HAVE ALSO GONE WITH OVERALL LESS CLOUD COVERAGE...ESPECIALLY
TONIGHT WHERE ANY DEBRIS CONVECTIVE CLOUDS WILL EITHER STAY
WITHIN THE MEAN FLOW OVER THE ATL WATERS...OR THE DEBRIS CLOUDS
THAT PUSH N-NE FROM GA WILL SCOUR OUT A GOOD DEAL PRIOR TO PUSHING
ACROSS THE FA.
AS FOR TEMPS...LOOKING AT WIDESPREAD 80S FOR MAX TEMPS
TODAY...AND WIDESPREAD 60S FOR MINS EXCEPT NEAR 70 ALONG THE
IMMEDIATE COAST AND EXTREME SOUTHERN PORTIONS OF THE FA. STAYED
WITH A SLIGHTLY COOLER BIAS FOR TONIGHTS MINS USING THE LATEST
AVBL MODEL MOS GUIDANCE.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 330 AM FRIDAY...DRY AIR CONTINUES TO FUNNEL INTO THE AREA
IN NORTHERLY FLOW ON BACK END OF LINGERING FRONT/TROUGH/OFF SHORE
ON SAT. A WAVE OF LOW PRESSURE DEVELOPS ALONG THE FRONT AND LIFTS
OFF TO THE NORTHEAST THROUGH LATE SAT INTO SUN LEAVING WEAK HIGH
PRESSURE OVER THE AREA THROUGH SUN NIGHT. THE NORTHERLY FLOW
BETWEEN HIGH PRESSURE INLAND AND LOW OFF SHORE ON SAT WILL BEGIN
TO VEER AROUND BECOMING MORE ON SHORE THROUGH SUNDAY. ABOVE THE
SURFACE...LOW PRESSURE ALOFT OVER THE CENTRAL GULF COAST WILL
BEGIN TO MOVE SLOWLY NORTHEAST AND WEAKEN PROVIDING A STEADY
SOUTHERLY FLOW OF MOISTURE INTO THE CAROLINAS IN THE LOW TO MID
LEVELS SAT NIGHT INTO SUNDAY. THIS IS DEPICTED WELL BY THE
MOISTURE PROFILES AND GUIDANCE SHOWING A DEEPENING OF MOISTURE
THROUGH THE COLUMN AND AN INCREASE IN CLOUD COVER ON SUNDAY. WITH
SUCH DRY AIR IN PLACE IN THE BEGINNING OF PERIOD...EXPECT LIMITED
TO NO SHWR ACTIVITY WITH A FEW SHWRS/TSTMS POSSIBLE IN LOCALIZED
CONVERGENCE MAINLY ASSOCIATED WITH THE SEA BREEZE OVER THE
WEEKEND...WITH MAINLY SOME HIGHER LEVEL CLOUDS AROUND. PCP WATER
VALUES DOWN LESS THAN AN INCH OVER INLAND NORTH CAROLINA INCREASE
UP TO 1.25 INCHES BY SAT EVE AND UP CLOSE TO 1.5 TO 1.75 INCHES
BY SUN AFTN IN A SLOW INCREASE IN MAINLY UPPER LEVEL MOISTURE.
THEREFORE EXPECT BETTER CHC OF CONVECTION ON SUNDAY BUT
GFS AND ECMWF BOTH SHOWING A WEAKENED ERIKA REACHING OVER SOUTHEAST
FLORIDA COAST SUN NIGHT INTO MON WITH EASTERLY FETCH OF MOISTURE
REACHING AS FAR NORTH AS SOUTH CAROLINA. OVERALL WESTWARD
ADJUSTMENT BY NHC AND GUIDANCE IS EVEN FARTHER WEST. MUCH
UNCERTAINTY STILL EXISTS WITH TRACK AND INTENSITY AND THEREFORE
WILL NEED TO ADJUST IN FUTURE FORECASTS.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 330 AM FRIDAY...TRENDING DRIER IN OVERALL FORECAST AS LATEST
MODEL RUNS SHOW ERIKA OVER FLORIDA ON MONDAY AND THEN TAKING A
TURN IN GEORGIA OR POSSIBLY TRACKING ACROSS FLORIDA TOWARD THE
GULF COAST. THIS WOULD PRODUCE A GREATER EXTENDED EAST TO
NORTHEASTERLY FETCH OVER THE CAROLINAS. FOR NOW KEPT WITH LOWER
END CHC POPS AND WITH GREATEST IMPACTS FROM ERIKA STILL EXPECTED
MID WEEK...WED INTO THURS. IF ERIKA DOES TAKE A TRACK TO OUR SOUTH
MAY END UP WITH MORE IN THE WAY OF SOME GUSTY ON SHORE WINDS AND
EXTENDED SWELL ENERGY PRODUCING SOME COASTAL IMPACTS BUT WITH SUCH
UNCERTAINTY IN THE MODELS IT IS STILL DIFFICULT TO SAY WITH ANY
CERTAINTY. LATEST GFS KEEPS PCP WATER VALUES LOWER THAN 1.5 INCHES
THROUGH MOST OF PERIOD OVER NC WITH VALUES REACHING UP CLOSE TO 2
INCHES ON NORTHERN STRETCH OF ERIKA INTO SOUTH CAROLINA. UPPER
RIDGE BUILDING OVER THE EASTERN CONUS WILL LEAVE A WEAKNESS BUT
TRACK WILL ALSO BE DEPENDENT ON STRENGTH OF ERIKA AS SHE MAKES HER
WEST NORTHWEST. THE GFS WANTS TO PULL ERIKA TOWARD THE WEST
GETTING PULLED BY THE MID TO UPPER LOW OVER THE WESTERN GULF.
OVERALL WENT A BIT MORE OPTIMISTIC FOR OUR AREA WITH A BIT LESS
CLOUD COVER AND LESS WIDESPREAD CONVECTION. RAISED MAX TEMPS A
BIT...EXPECTING MID TO UPPER 80S MOST PLACES WITH LOWS IN THE LOW
TO MID 70S.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 12Z...A FRONTAL SYSTEM IS LOCATED JUST OFF THE COAST THIS
MORNING WITH ISOLATED SHOWERS ALONG IT. AN AREA OF HIGH PRESSURE IS
TO THE N OF THE TERMINALS. AS A RESULT WINDS WILL BE NE-ENE TODAY AT
10-15 KTS AT ALL TERMINALS. DESPITE SOME IFR CIGS SOUTH OF KMYR VFR
WILL BE LIKELY TODAY. THERE IS ENOUGH MOISTURE TO HAVE SCT/BKN VFR
CIGS THROUGH MIDNIGHT Z AT THE COASTAL TERMINALS. SCT SKIES EXPECTED
AT KFLO/KLBT THROUGH THE TAF VALID PERIOD.
A LOW PRESSURE AREA WILL DEVELOP ALONG THE FRONT TODAY AND MOVE NE.
THERE IS A CHANCE SHOWERS OFFSHORE COULD MOVE TO NEAR THE COASTAL
TERMINALS...BUT ALL OF THE LATEST GUIDANCE SUGGEST THE CHANCE IS
VERY SMALL. THE BEST CHANCE HOWEVER...WOULD BE KMYR IN THE LATE
EVENING OR EARLY MORNING HOURS. WINDS DECREASE THIS EVENING TO 5 KT
OR LESS. GUIDANCE IS SUGGESTING FOG DEVELOPMENT OVERNIGHT WITH BEST
CHANCE AT KLBT. WILL NOT ADDRESS THIS IN TAFS ATTM.
EXTENDED OUTLOOK...PREDOMINATELY VFR WITH ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS THROUGH THE EXTENDED. BRIEF MORNING
FOG/STRATUS IS ALSO EXPECTED EACH DAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/... AS OF 1015 AM FRIDAY...MODERATE NE
SURGE OF DRY AIR CONTINUES...POSSIBLY STEADY STATE FOR THE NEXT
HANDFUL OF HOURS BUT STARTING TO ABATE AROUND MIDDAY. THIS HAS
GOTTEN WAVE FACES RATHER STEEP BUT NOT QUITE SCEC-WORTHY IN HEIGHT.
THERE ARE NO CHANGES TO THE FORECAST AT THIS TIME. PREVIOUS
DISCUSSION FOLLOWS:
AS OF 650 AM FRIDAY...THE ENTIRE ILM COASTAL WATERS SHOULD NOW BE
ENCOMPASSED WITH A STEADY AND MODEST NE WIND. THE SFC PG FROM THE
RIDGING FROM THE 1020+ HIGH FROM THE NORTH WILL BE TIGHT ENOUGH TO
PRODUCE A SOLID 15 KT SUSTAINED WIND...EXCEPT INITIALLY 15 TO 20
KT ACROSS THE ILM NC WATERS. LOOKING AT KLTX VWP AND ADJACENT 88D
VWPS...WINDS 1K TO 2K FT OFF THE DECK ARE RUNNING NE-ENE AT 15 TO
30 KT. WITH SOME OF THIS MIXING DOWN TO THE OCEAN SFC AS 20+ WIND
GUSTS. LOOK FOR A SOLID 15 KT NE WIND SPEED TONIGHT FOR ALL
WATERS...WIND DIRECTIONS MAY BRIEFLY VEER TO THE ENE-E NEAR SHORE
THIS AFTN/EARLY EVENING DUE TO A RESULTANT WIND BOUNDARY.
SIGNIFICANT SEAS WILL RUN A SOLID 4 FT FOR THE ILM NC WATERS FROM
CAPE FEAR NORTHWARD THRU THE PERIOD...AND 2 TO 4 FT SOUTH OF THE
CAPE. THE 4 TO 6 SECOND PERIOD WIND WAVES WILL DOMINATE THE
SIGNIFICANT SEAS...WITH THE UNDERLYING 1 TO 1.5 FOOT ESE GROUND
SWELL AT 11-12 SECOND PERIODS REMAINING VISUALLY PRESENT. THE
SCATTERED CONVECTION COVERAGE ASSOCIATED WITH THE SOMEWHAT STALLED
SFC FRONT...WILL SWITCH TO THE ADJACENT OFFSHORE WATERS.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 330 AM FRIDAY...NORTHEAST WINDS ON SATURDAY BETWEEN HIGH
PRESSURE EXTENDING DOWN OVER THE CAROLINAS AND WEAK LOW PRESSURE
DEVELOPING ALONG LINGERING BOUNDARY OFF SHORE. AS THIS LOW PULLS
AWAY THROUGH SUNDAY...WINDS MAY COME AROUND TO A MORE EASTERLY ON
SHORE DIRECTION AROUND HIGH PRESSURE. EXPECT DEEPEST MOISTURE AND
CONVECTION MAINLY EAST OF WATERS ASSOCIATED WITH LINGERING
BOUNDARY AND WAVE OF LOW PRESSURE ALONG IT. LATEST FORECAST TRACKS
WEAKENED ERIKA OVER FLORIDA BY SUNDAY NIGHT INTO EARLY MONDAY.
THIS WOULD MAINLY PRODUCE EASTERLY SWELL ENERGY REACHING INTO THE
LOCAL WATERS OVER THE WEEKEND WITH SEAS BASICALLY REMAINING 2 TO 4
FT MOST WATERS.
LONG TERM /MONDAY THROUGH TUESDAY/...
AS OF 330 AM FRIDAY...LATEST FORECAST TRACKS ERIKA OVER FLORIDA
AND KEEPS TRENDING WESTWARD WITH TIME GETTING PULLED BY MID TO
UPPER LOW IN THE WESTERN GULF. MAY SEE WINDS REMAIN E-NE ONLY
RISING UP TO 15 KTS. WITH SO MUCH UNCERTAINTY IN MODEL RUNS...WILL
NEED TO KEEP AN EYE ON EVOLUTION OF ERIKA. FOR NOW WILL KEEP
MAINLY EAST WINDS LESS THAN 15 KTS AND SEAS BASICALLY 2 TO 4 FT
WITH A DIMINISHING LONGER PERIOD SWELL.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...RGZ
NEAR TERM...MBB/DCH
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...MRR
.
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1023 AM CDT FRI AUG 28 2015
.UPDATE...
ISSUED AT 1019 AM CDT FRI AUG 28 2015
INITIAL BAND OF STORMS DROPPING SOUTHEAST FROM MANITOBA WAS SEVERE
WITH LARGE HAIL WINKLER MB TO PEMBINA ND REGION. THESE ARE
WEAKENING. QUESTION WILL BE RE-DEVELOPMENT. UPSTREAM WIND FIELD IS
QUITE CHAOTIC AND HARD TO TELL WHERE ANY TROUGH IS LOCATED. THAT
SAID SOME LOW LEVEL BOUNDARIES PRESENT WITH THE REMAINING SHOWERS
DROPPING SOUTH COULD HELP RE-FIRE ACTIVITY THIS AFTN. HRRR AND RAP
INDICATE THAT TO OCCUR POSSIBLY JMS-FAR-BJI AREA 21Z-00Z PERIOD.
DID ADJUST POPS A BIT TO INCREASE THEM THIS MORNING AND ADJUST A
TAD FARTHER WEST AND SOUTH TODAY.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 355 AM CDT FRI AUG 28 2015
VISIBILITY ACROSS NORTHWEST MINNESOTA WILL CONTINUE TO BE VARIABLE
IN PATCHY FOG THROUGH THE PREDAWN HOURS... THOUGH ANY FOG SHOULD
DISSIPATE SHORTLY AFTER SUNRISE.
A STRONG THUNDERSTORM COMPLEX IN SOUTHERN MANITOBA THIS HOUR IS
EXPECTED TO DIMINISH IN INTENSITY AS IT BRUSHES THE U.S. BORDER
ACROSS NORTHERN CAVALIER AND KITTSON COUNTIES AROUND 12Z. ISOLATED
SHOWER AND THUNDERSTORM ACTIVITY IS THEN POSSIBLE THROUGH THE
FORENOON THROUGHOUT THE NORTH BORDER COUNTIES... SPREADING ACROSS
FAR NORTHCENTRAL MINNESOTA THROUGH THE EARLY AFTERNOON.
A SECOND ROUND OF SCATTERED SHOWERS AND THUNDERSTORMS ARE
POSSIBLE...STARTING IN EAST CENTRAL ND FROM MID AFTERNOON AND
SPREADING EASTWARD ALONG AN EAST-WEST ORIENTED TROF AXIS INTO
NORTHWEST MINNESOTA INTO THE EARLY EVENING. EXTENT AND SEVERITY
OF THESE STORMS WILL DEPEND ON AFTERNOON HEATING... WITH AFTERNOON
TEMPERATURES REACHING INTO THE MID 80S IN SPOTS... THUS SOME
STORMS COULD PRODUCE SMALL HAIL AND GUSTY WINDS.
LATER TONIGHT AND SATURDAY WILL SEE A RETURN TO LIGHT SOUTHERLY
FLOW AND A DRIER...MORE STABLE H5 RIDGE BUILDING IN ALOFT.
TEMPERATURES OVERALL WILL BE A BIT WARMER THAN SEASONAL NORMALS.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 355 AM CDT FRI AUG 28 2015
SATURDAY NIGHT AND SUUNDAY...EXPECT MORE OF THE SAME. WITH A WARM
H5 RIDGE ALOFT AND LIGHT SOUTHERLY WINDS AT THE SURFACE...EXPECT
SEASONABLY WARM AND DRY CONDITIONS WITH HIGH TEMPERATURES RANGING
FRM THEMID 80S IN CENTRAL MINNESOTA LAKES COUNTRY TO THE LOWER 90S
IN THE DEVILS LAKE BASIN.
MONDAY-THURSDAY...A VERY SUMMER-LIKE WEATHER PATTERN WILL CONTINUE
HEADING INTO THE START OF SEPTEMBER. THE UPPER RIDGE WILL FLATTEN
EARLY ON WITH SHORTWAVE ENERGY PASSING NORTH ACROSS CANADA. AN
ASSOCIATED WEAK SFC BOUNDARY COULD FIRE A FEW STORMS OFF ON
MONDAY...ALTHOUGH THE BEST UPPER SUPPORT WILL BE WELL NORTH OVER
CANADA. THIS BOUNDARY SHOULD THEN WASH OUT WITHIN PERSISTENT
SOUTHWESTERLY FLOW ALOFT. NOT VERY OPTIMISTIC ABOUT PRECIP CHANCES
LATER IN THE PERIOD...ALTHOUGH A STORM COULD NOT BE RULED OUT GIVEN
THE SOUTHWEST FLOW PATTERN/RATHER MOIST ENVIRONMENT. WARMER MID-
LEVEL TEMPS MAY ACT TO SUPPRESS CONVECTION BY WED INTO THUR AS THE
PATTERN AMPLIFIES AHEAD OF AN APPROACHING FRONT. DETAILS OUT AT THIS
RANGE ARE STILL QUITE UNCERTAIN THOUGH.
AVE HIGHS/LOWS FALL INTO THE MID TO UPPER 70S/LOW 50S DURING EARLY
SEPT...BUT HIGHS SHOULD SHOULD REACH THE 80S WITH LOWS MAINLY IN THE
60S THROUGH THUR. WED AND POSSIBLY THUR LOOK TO BE WARMEST AS 850 MB
TEMPS RISE TO NEAR 25C. SO SOME HIGHS AT OR ABOVE 90 ARE POSSIBLE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
UPDATED AT 355 PM CDT THU AUG 27 2015
PATCHY FOG STILL POSSIBLE IN NORTHWEST AND WEST CENTAL MINESOTA
THROUGH THE EARLY MORNING...LARGELY DISSIPATING WITH SUNRISE.
ISOLD SHOWERS AND TSTMS EXPECTED ALONG THE NORTH BORDER COUNTIES
THIS FORENOON... WITH SCT TSTMS REDEVELOPING IN THE MID AFTERNOON
ACROSS EAST CENTRAL ND AND SPREADING INTO NORTHWEST MN FROM LATE
AFTERNONN INTO EARLY EVENING.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...RIDDLE
SHORT TERM...GUST
LONG TERM...GUST/MAKOWSKI
AVIATION...JR/GUST
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
712 AM CDT FRI AUG 28 2015
.UPDATE...
LATEST RADAR TRENDS SHOWED THE DEVELOPMENT OF ISOLATED TO
SCATTERED LIGHT SHOWERS ACROSS THE ROLLING PLAINS THIS
MORNING..AHEAD OF THE COLD FRONT. HAVE ADDED CHANCE POPS ACROSS
THE AFOREMENTIONED AREA.
&&
.PREV DISCUSSION... /ISSUED 629 AM CDT FRI AUG 28 2015/
AVIATION...
ISOLATED TO SCATTERED -SHRA AND -TSRA HAVE DEVELOPED NORTH OF
KCDS...WITH ISOLATED -SHRA DEVELOP CLOSE TO KCDS EARLY THIS
MORNING ALONG A COLD FRONT HAVE THEREFORE INSERTED A TEMPO FOR
-TSRA FOR A FEW HOURS THIS MORNING. ADDITIONAL DEVELOPMENT IS
POSSIBLE AT KLBB AND KPVW LATER THIS AFTERNOON AND
EVENING...THOUGH CONFIDENCE IS NOT HIGH ENOUGH TO INSERT A MENTION
AT THIS TIME. WILL OF COURSE AMEND AS NECESSARY. OTHERWISE OUTSIDE
OF ANY -SHRA/-TSRA...VFR CONDITIONS ARE EXPECTED AS SCT-BKN CLOUD
DECKS PASS OVERHEAD.
PREV DISCUSSION... /ISSUED 331 AM CDT FRI AUG 28 2015/
SHORT TERM...
UA RIDGE CENTERED TO OUR WEST HAS FLATTENED OUT A BIT THUS RESULTING
IN WNW FLOW ALOFT PREVAILING ACROSS THE SOUTHERN PLAINS. THIS DE-
AMPLIFICATION OF THE UA RIDGE IS DUE TO AN UA SHORTWAVE THAT HAS
TRACKED ENE FROM THE ROCKIES TO ACROSS THE CENTRAL/NORTHERN PLAINS
EARLY THIS MORNING. ITS ASSOCIATED COLD FRONT HAS BEEN SAGGING SWRD
ACROSS THE TX PANHANDLE AND HAS MOVED SOUTH OF KAMA AS OF 08Z.
ALTHOUGH THE BEST LARGE SCALE ASCENT IS WELL NORTH OF THE REGION...
SCATTERED CONVECTION HAS MANAGED TO DEVELOP IN THE WAKE OF THE
FRONT ACROSS THE TX PANHANDLE...COURTESY OF ADEQUATE FRONTOGENETICAL
FORCING. NOT ONLY ARE MODEL SOLUTIONS HAVING DIFFICULTY IN SHOWING
CONSENSUS WRT TO THE TIMING OF THE FRONT /IMPINGING ON THE NRN
ZONES ANYWHERE FROM 12-18Z/ BUT ARE ALSO HAVING DIFFICULTY IN THE
SPATIAL EXTENT OF PRECIP...THUS MAKING IT HARD TO HANG YOUR HAT ON
ANY ONE PARTICULAR SOLUTION. NONETHELESS...IF THE CURRENT SPEED OF
THE FRONT DOES NOT SLOW DOWN MUCH...IT APPEARS THAT THE FRONT WILL
MOVE ACROSS THE NRN ZONES AN HOUR OR SO BEFORE SUNRISE /AS HINTED
AT BY THE RAP SOLUTION/ AND THEREFORE PROGGED TO GET HUNG UP DURING
THE DAYTIME /ORIENTED FROM SW TO NE/...HENCE NOT QUITE CLEARING THE
LOW ROLLING PLAINS. SOLUTIONS DO EXHIBIT PRECIP ORIENTED FROM THE
SWRN ZONES TO THE NERN ZONES ALONG THE FRONT...THOUGH AS STATE
EARLIER...SOME SOLUTIONS ARE A BIT MORE BULLISH IN ITS SPATIAL
EXTENT AND QPF AMOUNTS. WILL THEREFORE HOLD ON TO BEST POPS BEING
SHOWN FROM SW TO NE...WITH LOWEST POPS ACROSS THE LOW ROLLING
PLAINS THROUGHOUT THE SHORT TERM PERIOD.
STEEPENING LAPSE RATES THIS AFTN COUPLED WITH DAYTIME DESTABILIZATION
MAY RESULT IN A FEW STORMS GENERATING BRIEF WIND GUSTS...BUT SEVERE
POTENTIAL APPEARS LOW GIVEN BEST UL SUPPORT WILL BE NORTH OF THE
REGION.
BEING THAT THE COLD FRONT IS NOT TERRIBLY STRONG /AS 850 MB TEMPS DO
NOT DROP TERRIBLY LOW/ IT WILL STILL BE A FEW DEGREES COOLER THAN
YESTERDAY WITH HIGHS RANGING FROM THE UPPER 80S ACROSS THE FAR SW TX
PANHANDLE TO THE UPPER 90S TO LOWER 100 DEGREE READINGS ACROSS THE
LOW ROLLING PLAINS. OVERNIGHT LOWS WILL BE IN THE 60S AND 70S.
LONG TERM...
A FAIRLY QUIET PERIOD COMING UP. THE LONG WAVE UPPER AIR PATTERN
OVER THE CONUS WILL REMAIN GENERALLY THE SAME THROUGH NEXT WEEK
WITH A TROUGH OVER THE WEST AND RIDGING FROM THE SRN PLAINS TO THE
NORTHEAST. HOWEVER...WEAKNESSES IN THE RIDGE WILL LEAVE HEIGHTS
AND THICKNESSES OVER THE AREA OF A MAGNITUDE THAT SHOULD KEEP
TEMPERATURES FROM GETTING TOO FAR OVER SEASONAL NORMS. ONLY OTHER
ISSUE IS POTENTIAL FOR GENERALLY AFTN AND EVENING PRECIP IN THE
NWRN COUNTIES VCNTY OF SFC TROUGH AND LOW LEVEL INSTABILITY AXIS.
MONDAY AND TUESDAY WOULD BE FAVORED. CONFIDENCE REMAINS LOW ATTM
AND HAVE KEPT MENTION OUT ATTM.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 87 61 89 61 / 20 20 10 0
TULIA 90 62 91 61 / 30 20 10 0
PLAINVIEW 89 63 91 63 / 30 30 10 0
LEVELLAND 93 64 91 64 / 30 30 10 10
LUBBOCK 94 65 92 65 / 30 30 10 0
DENVER CITY 93 63 91 63 / 20 30 10 0
BROWNFIELD 94 65 92 65 / 20 30 10 0
CHILDRESS 96 69 96 68 / 30 20 10 0
SPUR 98 69 94 67 / 20 20 10 10
ASPERMONT 100 72 97 70 / 20 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
29
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
629 AM CDT FRI AUG 28 2015
.AVIATION...
ISOLATED TO SCATTERED -SHRA AND -TSRA HAVE DEVELOPED NORTH OF
KCDS...WITH ISOLATED -SHRA DEVELOP CLOSE TO KCDS EARLY THIS
MORNING ALONG A COLD FRONT HAVE THEREFORE INSERTED A TEMPO FOR
-TSRA FOR A FEW HOURS THIS MORNING. ADDITIONAL DEVELOPMENT IS
POSSIBLE AT KLBB AND KPVW LATER THIS AFTERNOON AND
EVENING...THOUGH CONFIDENCE IS NOT HIGH ENOUGH TO INSERT A MENTION
AT THIS TIME. WILL OF COURSE AMEND AS NECESSARY. OTHERWISE OUTSIDE
OF ANY -SHRA/-TSRA...VFR CONDITIONS ARE EXPECTED AS SCT-BKN CLOUD
DECKS PASS OVERHEAD.
&&
.PREV DISCUSSION... /ISSUED 331 AM CDT FRI AUG 28 2015/
SHORT TERM...
UA RIDGE CENTERED TO OUR WEST HAS FLATTENED OUT A BIT THUS RESULTING
IN WNW FLOW ALOFT PREVAILING ACROSS THE SOUTHERN PLAINS. THIS DE-
AMPLIFICATION OF THE UA RIDGE IS DUE TO AN UA SHORTWAVE THAT HAS
TRACKED ENE FROM THE ROCKIES TO ACROSS THE CENTRAL/NORTHERN PLAINS
EARLY THIS MORNING. ITS ASSOCIATED COLD FRONT HAS BEEN SAGGING SWRD
ACROSS THE TX PANHANDLE AND HAS MOVED SOUTH OF KAMA AS OF 08Z.
ALTHOUGH THE BEST LARGE SCALE ASCENT IS WELL NORTH OF THE REGION...
SCATTERED CONVECTION HAS MANAGED TO DEVELOP IN THE WAKE OF THE
FRONT ACROSS THE TX PANHANDLE...COURTESY OF ADEQUATE FRONTOGENETICAL
FORCING. NOT ONLY ARE MODEL SOLUTIONS HAVING DIFFICULTY IN SHOWING
CONSENSUS WRT TO THE TIMING OF THE FRONT /IMPINGING ON THE NRN
ZONES ANYWHERE FROM 12-18Z/ BUT ARE ALSO HAVING DIFFICULTY IN THE
SPATIAL EXTENT OF PRECIP...THUS MAKING IT HARD TO HANG YOUR HAT ON
ANY ONE PARTICULAR SOLUTION. NONETHELESS...IF THE CURRENT SPEED OF
THE FRONT DOES NOT SLOW DOWN MUCH...IT APPEARS THAT THE FRONT WILL
MOVE ACROSS THE NRN ZONES AN HOUR OR SO BEFORE SUNRISE /AS HINTED
AT BY THE RAP SOLUTION/ AND THEREFORE PROGGED TO GET HUNG UP DURING
THE DAYTIME /ORIENTED FROM SW TO NE/...HENCE NOT QUITE CLEARING THE
LOW ROLLING PLAINS. SOLUTIONS DO EXHIBIT PRECIP ORIENTED FROM THE
SWRN ZONES TO THE NERN ZONES ALONG THE FRONT...THOUGH AS STATE
EARLIER...SOME SOLUTIONS ARE A BIT MORE BULLISH IN ITS SPATIAL
EXTENT AND QPF AMOUNTS. WILL THEREFORE HOLD ON TO BEST POPS BEING
SHOWN FROM SW TO NE...WITH LOWEST POPS ACROSS THE LOW ROLLING
PLAINS THROUGHOUT THE SHORT TERM PERIOD.
STEEPENING LAPSE RATES THIS AFTN COUPLED WITH DAYTIME DESTABILIZATION
MAY RESULT IN A FEW STORMS GENERATING BRIEF WIND GUSTS...BUT SEVERE
POTENTIAL APPEARS LOW GIVEN BEST UL SUPPORT WILL BE NORTH OF THE
REGION.
BEING THAT THE COLD FRONT IS NOT TERRIBLY STRONG /AS 850 MB TEMPS DO
NOT DROP TERRIBLY LOW/ IT WILL STILL BE A FEW DEGREES COOLER THAN
YESTERDAY WITH HIGHS RANGING FROM THE UPPER 80S ACROSS THE FAR SW TX
PANHANDLE TO THE UPPER 90S TO LOWER 100 DEGREE READINGS ACROSS THE
LOW ROLLING PLAINS. OVERNIGHT LOWS WILL BE IN THE 60S AND 70S.
LONG TERM...
A FAIRLY QUIET PERIOD COMING UP. THE LONG WAVE UPPER AIR PATTERN
OVER THE CONUS WILL REMAIN GENERALLY THE SAME THROUGH NEXT WEEK
WITH A TROUGH OVER THE WEST AND RIDGING FROM THE SRN PLAINS TO THE
NORTHEAST. HOWEVER...WEAKNESSES IN THE RIDGE WILL LEAVE HEIGHTS
AND THICKNESSES OVER THE AREA OF A MAGNITUDE THAT SHOULD KEEP
TEMPERATURES FROM GETTING TOO FAR OVER SEASONAL NORMS. ONLY OTHER
ISSUE IS POTENTIAL FOR GENERALLY AFTN AND EVENING PRECIP IN THE
NWRN COUNTIES VCNTY OF SFC TROUGH AND LOW LEVEL INSTABILITY AXIS.
MONDAY AND TUESDAY WOULD BE FAVORED. CONFIDENCE REMAINS LOW ATTM
AND HAVE KEPT MENTION OUT ATTM.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 87 61 89 61 / 20 20 10 0
TULIA 90 62 91 61 / 30 20 10 0
PLAINVIEW 89 63 91 63 / 30 30 10 0
LEVELLAND 93 64 91 64 / 30 30 10 10
LUBBOCK 94 65 92 65 / 30 30 10 0
DENVER CITY 93 63 91 63 / 20 30 10 0
BROWNFIELD 94 65 92 65 / 20 30 10 0
CHILDRESS 96 69 96 68 / 30 20 10 0
SPUR 98 69 94 67 / 20 20 10 10
ASPERMONT 100 72 97 70 / 10 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
29
AREA FORECAST DISCUSSION
NWS TUCSON AZ
930 AM MST FRI AUG 28 2015
.SYNOPSIS...LESS THUNDERSTORM COVERAGE THROUGH TONIGHT BEFORE
CHANCES INCREASE THIS WEEKEND. WE WILL KEEP ENOUGH MOISTURE FOR A
CHANCE OF THUNDERSTORMS FOR MOST OF NEXT WEEK. HOTTER THAN AVERAGE
TEMPERATURES FOR THE NEXT FEW DAYS BEFORE HIGH PRESSURE WEAKENS AND
TEMPERATURES SLOWLY FALL TO NEAR AVERAGE BY LATE NEXT WEEK.
&&
.DISCUSSION...IR/VISIBLE SATELLITE IMAGERY DEPICTED SUNNY SKIES
ACROSS MUCH OF SE ARIZONA AT THIS TIME. HOWEVER...MOSTLY CLOUDY
SKIES WERE ONGOING ACROSS ABOUT THE SOUTHEAST HALF OF COCHISE
COUNTY...SE GRAHAM COUNTY AND PORTIONS OF GREENLEE COUNTY. DEWPOINTS
AT LOWER ELEVATIONS VALID 16Z RANGED FROM THE UPPER 50S-LOWER 60S.
THESE TEMPS WERE ABOUT 2-5 DEGS F HIGHER FROM TUCSON WWD VERSUS 24
HOURS AGO...BUT WERE NEARLY 2-5 DEGS F LOWER ACROSS ERN SECTIONS.
28/12Z KTWC SOUNDING TOTAL PRECIP WATER VALUE OF 1.41 INCHES WAS
DOWN ABOUT 0.10 INCH VERSUS 24 HOURS AGO. THE ENVIRONMENT WAS
MODESTLY UNSTABLE WITH LI/S RANGING FROM MINUS 2-4 DEPENDING UPON
LIFTING METHOD. THE 700-300 MB FLOW WAS QUITE LIGHT...WITH MAINLY
WLY/NWLY SPEEDS AROUND 5 KTS. 28/12Z UPPER AIR PLOTS CONTINUED TO
DEPICT AN EXPANSIVE RIDGE OVER MUCH OF THE WRN CONUS WITH A 595 DM
HIGH CENTERED OVER SW NEW MEXICO. LIGHT WLY/NWLY FLOW PREVAILED
ACROSS SE ARIZONA ABOVE 700 MB.
28/12Z UNIV OF AZ WRF-NAM AND SEVERAL HRRR SOLUTIONS WERE QUITE
SIMILAR WITH DEPICTING THE INITIAL DEVELOPMENT OF SHOWERS/TSTMS BY
NOON TO BE ACROSS THE WHITE MOUNTAINS...THE CHIRICAHUA MOUNTAINS IN
ERN COCHISE COUNTY AND THE PINALENO MOUNTAINS IN GRAHAM COUNTY. THE
BULK OF SHOWERS/TSTMS THEN APPEARS TO BE LIMITED TO MAINLY NEAR THE
MOUNTAINS EAST-TO-SOUTHEAST OF TUCSON INTO THIS EVENING. STORM
MOTIONS SHOULD BE VERY SLOW AND GENERALLY SEWD. HOWEVER...CANNOT
RULE OUT THE POSSIBILITY OF SHOWERS/TSTMS IN VALLEY LOCALES AS FAR
WEST AS TUCSON DUE TO DEVELOPMENT FROM CONVECTIVE OUTFLOWS.
THUS...THE OFFICIAL FORECAST WILL CONTINUE WITH ISOLATED TO
SCATTERED SHOWERS/TSTMS INTO THIS EVENING. THE BULK OF THIS ACTIVITY
SHOULD BE EAST OF TUCSON. A SLIGHT CHANCE OF SHOWERS/TSTMS CONTINUES
LATE TONIGHT INTO SAT MORNING EAST AND SOUTH OF TUCSON. HIGH TEMPS
THIS AFTERNOON WILL AVERAGE ABOUT 3-6 DEGS F ABOVE NORMAL.
PLEASE REFER TO THE ADDITIONAL SECTIONS FOR FURTHER DETAIL.
&&
.AVIATION...VALID THRU 29/18Z.
EXPECT ISOLATED TO SCATTERED -TSRA/-SHRA MAINLY EAST AND SOUTH OF
KTUS INTO THIS EVENING. A FEW -TSRA/-SHRA MAY OCCUR LATE TONIGHT
INTO SATURDAY MORNING. MVFR CONDITIONS AND BRIEF WIND GUSTS OF 35-
45 KTS WILL OCCUR WITH THE STRONGER THUNDERSTORMS. OTHERWISE...CLOUD
DECKS WILL GENERALLY RANGE FROM 10-15K FT AGL AND SURFACE WIND WILL
MAINLY BE LESS THAN 10 KTS. AVIATION DISCUSSION NOT UPDATED FOR TAF
AMENDMENTS.
&&
.FIRE WEATHER...ISOLATED TO SCATTERED THUNDERSTORMS THIS AFTERNOON
AND EVENING MAINLY EAST AND SOUTH OF TUCSON. SCATTERED THUNDERSTORMS
WILL RETURN TO MUCH OF SOUTHEAST ARIZONA SATURDAY...THEN SCATTERED
THUNDERSTORMS WILL PREVAIL MAINLY FROM TUCSON EAST AND SOUTH SUNDAY
THROUGH THURSDAY. BRIEF STRONG...GUSTY AND ERRATIC WINDS WILL
ACCOMPANY THE STRONGER THUNDERSTORMS. OTHERWISE...GENERALLY LIGHT
TERRAIN DRIVEN WINDS WILL OCCUR INTO NEXT WEEK.
&&
.PREV DISCUSSION /230 AM MST/...SATURDAY AFTERNOON DOESN`T LOOK THAT
IMPRESSIVE AS THE HIGH CONTINUES TO SLOWLY WOBBLE EASTWARD...BUT BY
LATE SATURDAY AFTERNOON AND EARLY SATURDAY EVENING...OUR MID LEVEL
FLOW WILL BE IN THE PROCESS OF PICKING UP A BIT EAST OF TUCSON. THIS
WILL FAVOR ORGANIZED EASTERLY THUNDERSTORM OUTFLOW DEVELOPMENT AND
SHOULD PUSH SOME STORMS DEEPER INTO OUR CWA (INCLUDING THE TUCSON
AREA) EARLY SATURDAY EVENING. HEIGHTS AND THICKNESSES CONTINUE TO
SUPPORT HOTTER THAN AVERAGE TEMPERATURES...BUT MUCH DEPENDS ON
TIMING AND LOCATIONS OF STORMS.
EVEN AS THE RIDGE DEEPENS THROUGH NORTHERN TIER STATES IN OUR REGION
SUNDAY AND MONDAY...WE SHOULD MAINTAIN FAVORABLE THUNDERSTORM
CONDITIONS THROUGH SOUTHEAST ARIZONA AS OUR WEATHER CONTINUES TO BE
DOMINATED BY FEATURES IN SONORA.
THERE`S ONLY SO LONG WE CAN MAINTAIN A WESTERLY COMPONENT TO OUR
FLOW HOWEVER...SO A DRYING TREND WILL KICK IN SOONER OR LATER IF THE
REGION KEEPS THE MEAN TROUGH POSITION THROUGH THE COMING WEEK.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
FRANCIS
PREVIOUS DISCUSSION...MEYER
AREA FORECAST DISCUSSION
NWS PUEBLO CO
256 PM MDT FRI AUG 28 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 242 PM MDT FRI AUG 28 2015
TODAY AN UPR RIDGE IS OVR UT AND WRN CO...WITH NW FLOW ALOFT OVR ERN
CO AND A WEAK UPR DISTURBANCE MOVING THRU THE NW FLOW OVR ERN CO AND
WRN KS. THE NAM AND HRRR SHOW ISOLD TO SCT CONVECTION OVR THE HYR
TRRN AND PORTIONS OF THE I-25 CORRIDOR THRU THIS EVENING...BUT THE
HRRR ALSO SHOWS THE POTENTIAL FOR A FEW SHOWERS/TSTMS OVR THE SERN
PLAINS AS WELL. HAVE ALREADY SEEN A FEW ECHOES DEVELOP OVR BACA AND
ERN LAS ANIMAS COUNTIES...SO WL KEEP SOME ISOLD POPS FOR THESE
LOCATIONS THIS EVENING...BUT WL KEEP SILENT POPS OVR THE REST OF THE
SERN PLAINS. THE DISTURBANCE WILL EXIT THE REGION IN THE
EVENING...AND PCPN CHANCES ACRS THE AREA ARE GENERALLY EXPECTED TO
END BY MIDNIGHT.
ON SATURDAY THE UPR RIDGE MOVES OVR THE AREA. WITH LIMITED
MOISTURE...ONLY ISOLD TO SCT PCPN CHANCES ARE EXPECTED OVR THE NR
THE HYR TRRN. HIGH TEMPS SATURDAY SHOULD BE AROUND TO SLIGHTLY
ABOVE AVERAGE.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 242 PM MDT FRI AUG 28 2015
MODELS IN DECENT AGREEMENT THROUGH THE EXTENDED PERIOD WITH LOW
ENSEMBLE SPREADS. THE UPPER PATTERN WILL REMAIN NEARLY STATIONARY
WITH RIDGING NORTHWARD OUT OF THE DESERT SOUTHWEST...STRETCHING
NORTHEAST INTO THE NORTHERN PLAINS...AND AN UPPER TROUGH SITS
ALONG THE WEST COAST. EXPECT PERSISTENT SOUTHWESTERLY FLOW ALONG
WITH MONSOONAL MOISTURE TO CONTINUE ACROSS COLORADO THROUGH THE
EXTENDED PERIOD. SHOWER AND THUNDERSTORM CHANCES WILL BE HIGHLY
DEPENDENT UPON EMBEDDED ENERGY IN THE SOUTHWEST FLOW. CURRENT
MODEL ANALYSIS BRINGS NEAR DAILY DISTURBANCES ACROSS THE AREA
SATURDAY NIGHT THROUGH TUESDAY. SHOWERS AND THUNDERSTORMS ARE
FORECAST TO DEVELOP OVER THE MOUNTAINS DURING THE AFTERNOON
HOURS...AND SPREAD EAST INTO THE I-25 CORRIDOR DURING THE EVENING
BEFORE DISSIPATING OVERNIGHT. THE GFS IS DRIER ON WEDNESDAY AND
THURSDAY...AND THE ECMWF IS COMPLETELY DRY THESE DAYS. FOR NOW
HAVE LOW POPS IN THE FORECAST FOR THE MOUNTAINS WEDNESDAY AND
THURSDAY. A STRONGER DISTURBANCE IS LIKELY TO MOVE NORTH OUT OF
THE DESERT SOUTHWEST ON FRIDAY...WITH AN UPTICK IN SHOWER AND
THUNDERSTORM ACTIVITY. SHOWERS AND THUNDERSTORMS WILL BE CAPABLE
OF PRODUCING LOCALLY HEAVY RAINFALL...AND FLASH FLOODING WILL
CONTINUE TO BE A THREAT...ESPECIALLY ON AREA BURN SCARS. TEMPERATURES
WILL REMAIN WARM THROUGH THE EXTENDED PERIOD WITH 80S AND 90S
ACROSS MUCH OF THE AREA FOR AFTERNOON HIGHS. MOZLEY
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 242 PM MDT FRI AUG 28 2015
VFR CONDITIONS ARE EXPECTED AT THE TAF SITES TONIGHT THROUGH
SATURDAY AFTERNOON. THERE IS A SLIGHT CHANCE FOR ISOLD
SHOWERS/TSTMS IN THE VCNTY OF THE TAF SITES THIS EVENING.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...28
LONG TERM...MOZLEY
AVIATION...28
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
616 PM EDT FRI AUG 28 2015
.SYNOPSIS...
A FRONTAL BOUNDARY WILL REMAIN STALLED NEAR THE COAST THROUGH
TONIGHT...WITH DRY SURFACE HIGH PRESSURE REMAINING ANCHORED OVER
THE WESTERN AND CENTRAL CAROLINAS. INCREASING ATMOSPHERIC
MOISTURE WILL DRIFT SLOWLY NORTH INTO MAINLY SOUTHERN AND WESTERN
PORTIONS OF OUR REGION LATE SATURDAY...AND INTO REMAINING AREAS
SUNDAY. TROPICAL CYCLONE ERIKA IS EXPECTED TO APPROACH SOUTHERN
FLORIDA SUNDAY NIGHT. REFER TO THE LATEST ADVISORY ON ERIKA
ISSUED BY THE NATIONAL HURRICANE CENTER.
&&
.NEAR TERM /THROUGH SATURDAY/...
WEAK HIGH PRESSURE WILL REMAIN OVER THE SOUTHEAST FOR THE EVENING
AND OVERNIGHT HOURS. A WEAK FRONTAL BOUNDARY WILL REMAIN STALLED
OFF THE SC COAST. AS A RESULT...A NORTHEASTERLY/EASTERLY FLOW WILL
PERSIST OVER THE FORECAST AREA. LATEST RADAR LOOP SHOWING A FEW
SHOWERS MAINLY ALONG THE COAST AND ACROSS CNTRL/SRN GA. SLIGHT
CHANCE POPS MAINLY SOUTHERN FORECAST AREA STILL SEEMS APPROPRIATE
FOR THE EARLY EVENING HOURS.
OVERNIGHT...MAINLY DRY CONDITIONS UNDER PARTLY CLOUDY SKIES.
OVERNIGHT LOWS RANGING FROM THE MIDDLE 60S NORTH TO AROUND 70
SOUTH.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
MEAN UPPER TROUGH TO OUR WEST WITH UPPER RIDGE REMAINING CENTERED
TO OUR E AND SE. SHORTWAVE ENERGY MOVING EAST INTO THE MIDWEST
SAT/SUN WILL ALLOW UPPER ENERGY AND MOISTURE TO SLOWLY SHIFT
NORTH FROM THE GULF INTO OUR REGION. WITH THE EXCEPTION OF THE
NAM...MODELS CONTINUE TO TREND SLOWER WITH MOISTURE RETURN...AND
MAINLY RELEGATE IT TO THE S AND W FA SATURDAY...AS SURFACE HIGH
PRESSURE AND DRIER AIR REMAINS ENTRENCHED OVER THE WESTERN AND
CENTRAL CAROLINAS. THINK SLIGHT CHANCE POPS BY AFTERNOON FOR THE
S/W FA LOOK OK SATURDAY. MOISTURE EXPECTED TO CONTINUE TRENDING
SLOWLY NORTH SATURDAY NIGHT INTO SUNDAY...WITH INDICATIONS OF WEAK
SURFACE HIGH PRESSURE AND DRIER AIR STILL TRYING TO HANG TOUGH
OVER THE WESTERN CAROLINAS. MODELS INDICATE A POP GRADIENT OVER
OUR FA SUNDAY WITH LOWER POPS NORTH/HIGHER POPS SOUTH.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
UPPER TROUGH TO REMAIN TO OUR WEST WITH UPPER RIDGE TO OUR EAST.
MAIN CONCERN WILL CONTINUE TO BE STATUS AND TRACK OF TROPICAL
CYCLONE ERIKA. OFFICIAL FORECASTS BRING THE SYSTEM INTO S FLORIDA
BY LATE SUN...AND NORTHWARD INTO N FL/S GA VICINITY BY WED. EVEN
WITHOUT THE CYCLONE IN PLAY...IT APPEARS SUFFICIENT ATMOSPHERIC
MOISTURE WOULD PROVIDE PREMISE FOR SCATTERED DIURNAL CONVECTION
OVER OUR FA ANYWAY. DUE TO UNCERTAINTIES REGARDING POSSIBLE
IMPACT OF ERIKA ON OUR REGION...WILL CONTINUE TO MAINTAIN ONGOING
FORECAST OF CHANCE POPS...TRENDED A LITTLE HIGHER TO THE SOUTH.
GENERALLY BLENDED LATEST GUIDANCE WITH ONGOING FORECAST.
&&
.AVIATION /22Z FRIDAY THROUGH WEDNESDAY/...
LINGERING LOW-LEVEL MOISTURE AND NOCTURNAL COOLING MAY LEAD TO
STRATUS AND FOG DURING THE EARLY MORNING HOURS. THE NAM MOS
INDICATED MVFR OR IFR CONDITIONS 06Z TO 15Z. THE GFS MOS PLUS SREF
AND HRRR GUIDANCE GENERALLY MAINTAINED VFR CONDITIONS. WE LEANED
TOWARD THE MORE OPTIMISTIC GUIDANCE BASED ON UPPER MOISTURE
STREAMING INTO THE AREA LIMITING NET RADIATIONAL COOLING AND
SURFACE HIGH PRESSURE TO THE NORTH PUSHING DRY AIR TOWARD THE
AREA. AN INCREASE IN MOISTURE AND HEATING MAY HELP SUPPORT
THUNDERSTORMS SATURDAY AFTERNOON BUT EXPECT SCATTERED COVERAGE
WITH THE CHANCE TOO LOW TO INCLUDE IN THE TERMINAL FORECASTS AT
THIS TIME.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE IN MAINLY EARLY
MORNING FOG AND STRATUS PLUS AFTERNOON AND EVENING SCATTERED
THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
77
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
607 PM EDT FRI AUG 28 2015
.SYNOPSIS...
A FRONTAL BOUNDARY WILL REMAIN STALLED NEAR THE COAST THROUGH
TONIGHT...WITH DRY SURFACE HIGH PRESSURE REMAINING ANCHORED OVER
THE WESTERN AND CENTRAL CAROLINAS. INCREASING ATMOSPHERIC
MOISTURE WILL DRIFT SLOWLY NORTH INTO MAINLY SOUTHERN AND WESTERN
PORTIONS OF OUR REGION LATE SATURDAY...AND INTO REMAINING AREAS
SUNDAY. TROPICAL CYCLONE ERIKA IS EXPECTED TO APPROACH SOUTHERN
FLORIDA SUNDAY. REFER TO THE LATEST ADVISORY ON ERIKA ISSUED BY
THE NATIONAL HURRICANE CENTER.
&&
.NEAR TERM /THROUGH SATURDAY/...
WEAK HIGH PRESSURE WILL REMAIN OVER THE SOUTHEAST FOR THE REST OF
THE AFTERNOON THROUGH TONIGHT WITH A WEAK FRONTAL BOUNDARY STALLED
OFF THE SC COAST. AS A RESULT...A NORTHEASTERLY/EASTERLY FLOW WILL
PERSIST OVER THE FORECAST AREA. LATEST RADAR LOOP SHOWING A FEW
SHOWERS MAINLY ALONG THE COAST AND OVER THE CSRA. LATEST HRRR
SHOWING ISOLATED COVERAGE AT BEST THIS AFTERNOON. SLIGHT CHANCE
POPS MAINLY SOUTHERN FORECAST AREA STILL SEEMS APPROPRIATE. HIGH
TEMPERATURES ARE FORECAST NEAR NORMAL...IN THE UPPER 80S.
FOR TONIGHT...MAINLY DRY CONDITIONS UNDER PARTLY CLOUDY SKIES.
OVERNIGHT LOWS RANGING FROM THE MIDDLE 60S NORTH TO AROUND 70 SOUTH.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
MEAN UPPER TROUGH TO OUR WEST WITH UPPER RIDGE REMAINING CENTERED
TO OUR E AND SE. SHORTWAVE ENERGY MOVING EAST INTO THE MIDWEST
SAT/SUN WILL ALLOW UPPER ENERGY AND MOISTURE TO SLOWLY SHIFT
NORTH FROM THE GULF INTO OUR REGION. WITH THE EXCEPTION OF THE
NAM...MODELS CONTINUE TO TREND SLOWER WITH MOISTURE RETURN...AND
MAINLY RELEGATE IT TO THE S AND W FA SATURDAY...AS SURFACE HIGH
PRESSURE AND DRIER AIR REMAINS ENTRENCHED OVER THE WESTERN AND
CENTRAL CAROLINAS. THINK SLIGHT CHANCE POPS BY AFTERNOON FOR THE
S/W FA LOOK OK SATURDAY. MOISTURE EXPECTED TO CONTINUE TRENDING
SLOWLY NORTH SATURDAY NIGHT INTO SUNDAY...WITH INDICATIONS OF WEAK
SURFACE HIGH PRESSURE AND DRIER AIR STILL TRYING TO HANG TOUGH
OVER THE WESTERN CAROLINAS. MODELS INDICATE A POP GRADIENT OVER
OUR FA SUNDAY WITH LOWER POPS NORTH/HIGHER POPS SOUTH.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
UPPER TROUGH TO REMAIN TO OUR WEST WITH UPPER RIDGE TO OUR EAST.
MAIN CONCERN WILL CONTINUE TO BE STATUS AND TRACK OF TROPICAL
CYCLONE ERIKA. OFFICIAL FORECASTS BRING THE SYSTEM INTO S FLORIDA
BY LATE SUN...AND NORTHWARD INTO N FL/S GA VICINITY BY WED. EVEN
WITHOUT THE CYCLONE IN PLAY...IT APPEARS SUFFICIENT ATMOSPHERIC
MOISTURE WOULD PROVIDE PREMISE FOR SCATTERED DIURNAL CONVECTION
OVER OUR FA ANYWAY. DUE TO UNCERTAINTIES REGARDING POSSIBLE
IMPACT OF ERIKA ON OUR REGION...WILL CONTINUE TO MAINTAIN ONGOING
FORECAST OF CHANCE POPS...TRENDED A LITTLE HIGHER TO THE SOUTH.
GENERALLY BLENDED LATEST GUIDANCE WITH ONGOING FORECAST.
&&
.AVIATION /22Z FRIDAY THROUGH WEDNESDAY/...
LINGERING LOW-LEVEL MOISTURE AND NOCTURNAL COOLING MAY LEAD TO
STRATUS AND FOG DURING THE EARLY MORNING HOURS. THE NAM MOS
INDICATED MVFR OR IFR CONDITIONS 06Z TO 15Z. THE GFS MOS PLUS SREF
AND HRRR GUIDANCE GENERALLY MAINTAINED VFR CONDITIONS. WE LEANED
TOWARD THE MORE OPTIMISTIC GUIDANCE BASED ON UPPER MOISTURE
STREAMING INTO THE AREA LIMITING NET RADIATIONAL COOLING AND
SURFACE HIGH PRESSURE TO THE NORTH PUSHING DRY AIR TOWARD THE
AREA. AN INCREASE IN MOISTURE AND HEATING MAY HELP SUPPORT
THUNDERSTORMS SATURDAY AFTERNOON BUT EXPECT SCATTERED COVERAGE
WITH THE CHANCE TOO LOW TO INCLUDE IN THE TERMINAL FORECASTS AT
THIS TIME.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE IN MAINLY EARLY
MORNING FOG AND STRATUS PLUS AFTERNOON AND EVENING SCATTERED
THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
99
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
500 PM CDT FRI AUG 28 2015
.SHORT TERM...
TONIGHT AND SATURDAY...
250 PM...FORECAST CONCERNS INCLUDE PRECIP COVERAGE/TIMING AND
RAINFALL AMOUNTS.
LOW PRESSURE OVER WESTERN IOWA WILL SLOWLY MOVE EAST TONIGHT AND
EVENTUALLY DISSIPATE OVER NORTHERN ILLINOIS SATURDAY. FIRST WAVE OF
PRECIP IS GENERALLY LIFTING NORTHEAST INTO SOUTHERN WISCONSIN AND
THE MODELS SEEM TO HAVE THIS HANDLED FAIRLY WELL WITH THE HRRR ALSO
SHOWING JUST ISOLATED SHOWERS/SPRINKLES INTO EARLY THIS EVENING AND
MAINLY ACROSS NORTHWEST AND NORTHERN IL. ADDITIONAL PRECIP IS
EXPECTED TO DEVELOP LATER THIS EVENING AND SPREAD NORTHEAST
OVERNIGHT INTO SATURDAY MORNING. THIS PRECIP WILL ALSO BE FOCUSED
ACROSS NORTHWEST/NORTHERN IL...INTO SOUTHERN WI. MODEL QPF AMOUNTS
NEAR THE IL/WI STATE LINE ARE IN THE 1 TO 1.5 INCH RANGE. THESE
AMOUNTS HAVE BEEN CONSISTENT BETWEEN RUNS AND VARIOUS MODELS SO IT
IS LIKELY SOME AREAS WILL SEE OVER AN INCH OF RAIN. HOWEVER...THESE
AMOUNTS APPEAR TO DROP OFF QUICKLY BETWEEN I-88 AND I-80 WITH MUCH
OF THE SOUTHEAST THIRD OR HALF OF THE CWA POSSIBLY STAYING DRY INTO
SATURDAY MORNING. INSTABILITY IS LIMITED AND LIGHTNING HAS BEEN
CONFINED TO THE STRONGEST STORMS/CONVECTION. THUNDER IS CERTAINLY
POSSIBLE TONIGHT BUT OVERALL COVERAGE SHOULD BE LIMITED AND HELD
SLIGHT CHANCE MENTION OF THUNDER TO HIGHER POP AREAS.
AFTER THE MAIN AREA OF RAIN MOVES NORTHEAST SATURDAY MORNING...
PRECIP ACROSS THE REST OF THE CWA WILL BE MORE SCATTERED...OR
ISOLATED...INTO THE LATE MORNING/EARLY AFTERNOON. APPEARS THERE
COULD BE NEW DEVELOPMENT IN THE EARLY/MID AFTERNOON BUT COVERAGE
POSSIBLY STILL JUST SCATTERED. THUS DIDN/T MAKE TOO MANY CHANGES
FROM CURRENT POPS IN THE 40-50 PERCENT RANGE.
TEMPS WILL ONLY SLOWLY FALL INTO THE LOWER/MID 60S TONIGHT AND HIGHS
ON SATURDAY WILL BE DEPENDENT ON PRECIP COVERAGE AND CLOUD COVER.
CURRENT FORECAST OF MID 70S NORTH TO LOWER 80S SOUTHEAST WILL
NEED SOME SUN TO OCCUR. SOUTHEASTERLY WINDS WILL KEEP THE IL SHORE
A BIT COOLER. CMS
&&
.LONG TERM...
307 PM CDT
SATURDAY NIGHT THROUGH FRIDAY...
THE LATEST LONGER TERM GUIDANCE IS INDICATING SOME CHANGES POSSIBLE
FOR THE LONGER RANGE TRENDS FOR TEMPERATURES AND PCPN...BUT THE
EARLIER PORTION OF THE LONG TERM FORECAST IS RELATIVELY CONSISTENT
WITH PREVIOUS RUNS.
THE GENERAL TREND FOR TEMPERATURES IS STILL FOR A WARMING TREND FOR
NEXT WEEK...BUT TEMPERATURES SHOULD STILL BE SLIGHTLY BELOW NORMAL
THROUGH SUNDAY. FOR SATURDAY NIGHT AND INTO EARLY SUNDAY...THERE
SHOULD STILL BE A CHANCE OF SOME LINGERING SHOWERS OR A FEW
THUNDERSTORMS...ESPECIALLY FOR NWRN INDIANA AS THE UPPER LEVEL
SHORTWAVE RESPONSIBLE FOR FOCUSING THE CONVECTIVE ACTIVITY LIFTS
OFF TO THE EAST AND WEAKENS. BY SUNDAY...LEE TROUGHING WILL DEVELOP
OVER THE WRN PLAINS AS A NORTHERN STREAM SHORTWAVE AND AN ASSOCIATED
SFC REFLECTION DROPS OUT OF THE CANADIAN ROCKIES AND INTO THE
PRAIRIES. THE OVERALL PATTERN WILL BECOME NEARLY STATIONARY THROUGH
MUCH OF NEXT WEEK AS THE SFC HIGH REMAINS PARKED OVER THE MID
ATLANTIC REGION WHILE THE TROUGH REMAINS OVER THE PLAINS. THIS WILL
HELP AID THE WARMING TREND AS SLY WINDS TRY TO DRAW MOISTURE NWD
FROM THE GLFMEX...THOUGH WEAK SFC RIDGING THROUGH THE NRN GULF COAST
MAY CAUSE SOME DELAY IN THE MOISTURE RETURN.
THE MAIN CHANGE TO THE EXTENDED FORECAST IS RELATED TO HOW THE
MODELS NOW HANDLE THE REMNANTS OF TS ERIKA. PREVIOUS RUNS OF THE
LONGER RANGE GUIDANCE HAD PREVIOUSLY LIMITED THE WESTWARD
PROGRESSION OF THE TROPICAL SYSTEM...WHILE THE LATEST RUNS ARE
HINTING THAT ERIKA COULD TRACK FARTHER WEST. SO...WHILE THERE IS
STILL A FAIR AMOUNT OF UNCERTAINTY IN HOW FAR WEST THE PERIPHERAL
EFFECT OF THE TROPICAL SYSTEM WILL EXTEND...AND WE ARE NOT TALKING
ABOUT THE TROPICAL SYSTEM ACTUALLY MOVING ANYWHERE CLOSE TO NRN
IL/IN...RATHER THE IDEA IS THAT IF THE TROPICAL SYSTEM CAN TRACK A
LITTLE FURTHER WEST...THEN THERE WILL BE GREATER MOISTURE TRANSPORT
INTO THE MIDWEST...AND AS A RESULT...GREATER CHANCES FOR SHRA/TSRA
AND MORE CLOUD COVER THAN PREVIOUSLY ANTICIPATED. SO HAVE BACKED
OFF A COUPLE DEGREES ON MAX TEMPS THROUGH THE EXTENDED PERIOD AS
WELL AS INTRODUCING PERIODIC SLIGHT CHANCE POPS AND A BIT MORE CLOUD
COVER.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* CHANCE OF SHRA/SLIGHT CHANCE OF TS TONIGHT INTO SAT MORNING.
SLIGHTLY BETTER CHANCE OF THUNDER SATURDAY AFTERNOON.
KJB/BMD
//DISCUSSION...UPDATED 18Z...
AN ATMOSPHERIC DISTURBANCE...CURRENTLY DRIVING AN AREA OF SHOWERS
AND EMBEDDED STORMS OVER IOWA...WILL GRADUALLY SHIFT EASTWARD
TONIGHT. HOWEVER...IT APPEARS THE MAIN FOCUS FOR SHOWERS AND ANY
STORMS MAY LARGELY REMAIN NORTH OF THE EASTERN TERMINALS...ACROSS
FAR NORTHERN ILLINOIS AND INTO WISCONSIN. BETTER CHANCES OF MORE
SUBSTANTIAL SHOWERS LOOKS TO ENTER THE PICTURE AFTER DAYBREAK
SATURDAY...AND CONTINUING AT TIMES INTO THE AFTERNOON. IT APPEARS
THE THUNDER THREAT WILL BE LOW WITH MUCH OF THIS ACTIVITY.
HOWEVER...THERE WILL BE A SLIGHT BETTER CHANCE OF THUNDER SUNDAY
AFTERNOON AS A FRONTAL ZONE SAGS SOUTHEASTWARD OVER THE AREA.
GIVEN THIS...I HAVE OPTED TO ADD A PROB30 FOR A PERIOD OF THUNDER
LATER SATURDAY AFTERNOON AT THE END OF THE 30 HOUR ORD TAF.
KJB
//ORD AND MDW CONFIDENCE...UPDATED 22Z...
* MEDIUM WITH PRECIP CHANCES/TIMING...ESPECIALLY SATURDAY
MORNING/EARLY AFTERNOON.
* LOW WITH THREAT OF THUNDER DURING THE PERIOD.
* HIGH CONFIDENCE IN REMAINING FORECAST ELEMENTS.
KJB/BMD
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...SLIGHT CHANCE OF TSRA...OTHERWISE VFR.
SUNDAY...VFR. NORTHEAST WINDS.
MONDAY THROUGH THURSDAY...VFR. SOUTHERLY WINDS...POSSIBLE
AFTERNOON WIND SHIFTS TO EASTERLY WITH LAKE BREEZES EACH
AFTERNOON.
IZZI
&&
.MARINE...
310 PM CDT
HIGH PRESSURE OVER THE MID ATLANTIC REGION WILL MOVE VERY LITTLE
THROUGH THE MIDDLE OF NEXT WEEK. WEAK LOW PRESSURE OVER WESTERN
IOWA WILL WEAKEN AS IT MOVES INTO THE MIDDLE MISSISSIPPI VALLEY
AND DISSIPATES SATURDAY EVENING. ANOTHER AREA OF LOW PRESSURE IS
EXPECTED TO DROP OUT OF THE CANADIAN ROCKIES SUNDAY NIGHT WHILE A
TROUGH OF LOW PRESSURE DEVELOPS OVER THE WESTERN PLAINS. THIS
TROUGH AND THE HIGH OVER THE MID ATLANTIC REGION WILL MOVE LITTLE
OVER THE NEXT SEVERAL DAYS...KEEPING MODEST SOUTH TO SOUTHWEST
WINDS OVER THE LAKE FOR THE NEXT SEVERAL DAYS.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
310 PM CDT FRI AUG 28 2015
.SHORT TERM...
TONIGHT AND SATURDAY...
250 PM...FORECAST CONCERNS INCLUDE PRECIP COVERAGE/TIMING AND
RAINFALL AMOUNTS.
LOW PRESSURE OVER WESTERN IOWA WILL SLOWLY MOVE EAST TONIGHT AND
EVENTUALLY DISSIPATE OVER NORTHERN ILLINOIS SATURDAY. FIRST WAVE OF
PRECIP IS GENERALLY LIFTING NORTHEAST INTO SOUTHERN WISCONSIN AND
THE MODELS SEEM TO HAVE THIS HANDLED FAIRLY WELL WITH THE HRRR ALSO
SHOWING JUST ISOLATED SHOWERS/SPRINKLES INTO EARLY THIS EVENING AND
MAINLY ACROSS NORTHWEST AND NORTHERN IL. ADDITIONAL PRECIP IS
EXPECTED TO DEVELOP LATER THIS EVENING AND SPREAD NORTHEAST
OVERNIGHT INTO SATURDAY MORNING. THIS PRECIP WILL ALSO BE FOCUSED
ACROSS NORTHWEST/NORTHERN IL...INTO SOUTHERN WI. MODEL QPF AMOUNTS
NEAR THE IL/WI STATE LINE ARE IN THE 1 TO 1.5 INCH RANGE. THESE
AMOUNTS HAVE BEEN CONSISTENT BETWEEN RUNS AND VARIOUS MODELS SO IT
IS LIKELY SOME AREAS WILL SEE OVER AN INCH OF RAIN. HOWEVER...THESE
AMOUNTS APPEAR TO DROP OFF QUICKLY BETWEEN I-88 AND I-80 WITH MUCH
OF THE SOUTHEAST THIRD OR HALF OF THE CWA POSSIBLY STAYING DRY INTO
SATURDAY MORNING. INSTABILITY IS LIMITED AND LIGHTNING HAS BEEN
CONFINED TO THE STRONGEST STORMS/CONVECTION. THUNDER IS CERTAINLY
POSSIBLE TONIGHT BUT OVERALL COVERAGE SHOULD BE LIMITED AND HELD
SLIGHT CHANCE MENTION OF THUNDER TO HIGHER POP AREAS.
AFTER THE MAIN AREA OF RAIN MOVES NORTHEAST SATURDAY MORNING...
PRECIP ACROSS THE REST OF THE CWA WILL BE MORE SCATTERED...OR
ISOLATED...INTO THE LATE MORNING/EARLY AFTERNOON. APPEARS THERE
COULD BE NEW DEVELOPMENT IN THE EARLY/MID AFTERNOON BUT COVERAGE
POSSIBLY STILL JUST SCATTERED. THUS DIDN/T MAKE TOO MANY CHANGES
FROM CURRENT POPS IN THE 40-50 PERCENT RANGE.
TEMPS WILL ONLY SLOWLY FALL INTO THE LOWER/MID 60S TONIGHT AND HIGHS
ON SATURDAY WILL BE DEPENDENT ON PRECIP COVERAGE AND CLOUD COVER.
CURRENT FORECAST OF MID 70S NORTH TO LOWER 80S SOUTHEAST WILL
NEED SOME SUN TO OCCUR. SOUTHEASTERLY WINDS WILL KEEP THE IL SHORE
A BIT COOLER. CMS
&&
.LONG TERM...
307 PM CDT
SATURDAY NIGHT THROUGH FRIDAY...
THE LATEST LONGER TERM GUIDANCE IS INDICATING SOME CHANGES POSSIBLE
FOR THE LONGER RANGE TRENDS FOR TEMPERATURES AND PCPN...BUT THE
EARLIER PORTION OF THE LONG TERM FORECAST IS RELATIVELY CONSISTENT
WITH PREVIOUS RUNS.
THE GENERAL TREND FOR TEMPERATURES IS STILL FOR A WARMING TREND FOR
NEXT WEEK...BUT TEMPERATURES SHOULD STILL BE SLIGHTLY BELOW NORMAL
THROUGH SUNDAY. FOR SATURDAY NIGHT AND INTO EARLY SUNDAY...THERE
SHOULD STILL BE A CHANCE OF SOME LINGERING SHOWERS OR A FEW
THUNDERSTORMS...ESPECIALLY FOR NWRN INDIANA AS THE UPPER LEVEL
SHORTWAVE RESPONSIBLE FOR FOCUSING THE CONVECTIVE ACTIVITY LIFTS
OFF TO THE EAST AND WEAKENS. BY SUNDAY...LEE TROUGHING WILL DEVELOP
OVER THE WRN PLAINS AS A NORTHERN STREAM SHORTWAVE AND AN ASSOCIATED
SFC REFLECTION DROPS OUT OF THE CANADIAN ROCKIES AND INTO THE
PRAIRIES. THE OVERALL PATTERN WILL BECOME NEARLY STATIONARY THROUGH
MUCH OF NEXT WEEK AS THE SFC HIGH REMAINS PARKED OVER THE MID
ATLANTIC REGION WHILE THE TROUGH REMAINS OVER THE PLAINS. THIS WILL
HELP AID THE WARMING TREND AS SLY WINDS TRY TO DRAW MOISTURE NWD
FROM THE GLFMEX...THOUGH WEAK SFC RIDGING THROUGH THE NRN GULF COAST
MAY CAUSE SOME DELAY IN THE MOISTURE RETURN.
THE MAIN CHANGE TO THE EXTENDED FORECAST IS RELATED TO HOW THE
MODELS NOW HANDLE THE REMNANTS OF TS ERIKA. PREVIOUS RUNS OF THE
LONGER RANGE GUIDANCE HAD PREVIOUSLY LIMITED THE WESTWARD
PROGRESSION OF THE TROPICAL SYSTEM...WHILE THE LATEST RUNS ARE
HINTING THAT ERIKA COULD TRACK FARTHER WEST. SO...WHILE THERE IS
STILL A FAIR AMOUNT OF UNCERTAINTY IN HOW FAR WEST THE PERIPHERAL
EFFECT OF THE TROPICAL SYSTEM WILL EXTEND...AND WE ARE NOT TALKING
ABOUT THE TROPICAL SYSTEM ACTUALLY MOVING ANYWHERE CLOSE TO NRN
IL/IN...RATHER THE IDEA IS THAT IF THE TROPICAL SYSTEM CAN TRACK A
LITTLE FURTHER WEST...THEN THERE WILL BE GREATER MOISTURE TRANSPORT
INTO THE MIDWEST...AND AS A RESULT...GREATER CHANCES FOR SHRA/TSRA
AND MORE CLOUD COVER THAN PREVIOUSLY ANTICIPATED. SO HAVE BACKED
OFF A COUPLE DEGREES ON MAX TEMPS THROUGH THE EXTENDED PERIOD AS
WELL AS INTRODUCING PERIODIC SLIGHT CHANCE POPS AND A BIT MORE CLOUD
COVER.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* WIND SHIFT TO EAST-SOUTHEASTERLY LIKELY EARLY THIS EVENING.
* CHANCE OF SHRA/SLIGHT CHANCE OF TS TONIGHT INTO SAT MORNING.
SLIGHTLY BETTER CHANCE OF THUNDER SATURDAY AFTERNOON.
KJB
//DISCUSSION...UPDATED 18Z...
AN ATMOSPHERIC DISTURBANCE...CURRENTLY DRIVING AN AREA OF SHOWERS
AND EMBEDDED STORMS OVER IOWA...WILL GRADUALLY SHIFT EASTWARD
TONIGHT. HOWEVER...IT APPEARS THE MAIN FOCUS FOR SHOWERS AND ANY
STORMS MAY LARGELY REMAIN NORTH OF THE EASTERN TERMINALS...ACROSS
FAR NORTHERN ILLINOIS AND INTO WISCONSIN. BETTER CHANCES OF MORE
SUBSTANTIAL SHOWERS LOOKS TO ENTER THE PICTURE AFTER DAYBREAK
SATURDAY...AND CONTINUING AT TIMES INTO THE AFTERNOON. IT APPEARS
THE THUNDER THREAT WILL BE LOW WITH MUCH OF THIS ACTIVITY.
HOWEVER...THERE WILL BE A SLIGHT BETTER CHANCE OF THUNDER SUNDAY
AFTERNOON AS A FRONTAL ZONE SAGS SOUTHEASTWARD OVER THE AREA.
GIVEN THIS...I HAVE OPTED TO ADD A PROB30 FOR A PERIOD OF THUNDER
LATER SATURDAY AFTERNOON AT THE END OF THE 30 HOUR ORD TAF.
KJB
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH WITH WIND SHIFT TO SOUTHEAST THIS EVENING...LOW WITH PRECISE
SPEEDS AND TIMING.
* MEDIUM WITH PRECIP CHANCES/TIMING...ESPECIALLY SATURDAY
MORNING/EARLY AFTERNOON.
* LOW WITH THREAT OF THUNDER DURING THE PERIOD.
* HIGH CONFIDENCE IN REMAINING FORECAST ELEMENTS.
KJB
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...SLIGHT CHANCE OF TSRA...OTHERWISE VFR.
SUNDAY...VFR. NORTHEAST WINDS.
MONDAY THROUGH THURSDAY...VFR. SOUTHERLY WINDS...POSSIBLE
AFTERNOON WIND SHIFTS TO EASTERLY WITH LAKE BREEZES EACH
AFTERNOON.
IZZI
&&
.MARINE...
310 PM CDT
HIGH PRESSURE OVER THE MID ATLANTIC REGION WILL MOVE VERY LITTLE
THROUGH THE MIDDLE OF NEXT WEEK. WEAK LOW PRESSURE OVER WESTERN
IOWA WILL WEAKEN AS IT MOVES INTO THE MIDDLE MISSISSIPPI VALLEY
AND DISSIPATES SATURDAY EVENING. ANOTHER AREA OF LOW PRESSURE IS
EXPECTED TO DROP OUT OF THE CANADIAN ROCKIES SUNDAY NIGHT WHILE A
TROUGH OF LOW PRESSURE DEVELOPS OVER THE WESTERN PLAINS. THIS
TROUGH AND THE HIGH OVER THE MID ATLANTIC REGION WILL MOVE LITTLE
OVER THE NEXT SEVERAL DAYS...KEEPING MODEST SOUTH TO SOUTHWEST
WINDS OVER THE LAKE FOR THE NEXT SEVERAL DAYS.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
250 PM CDT FRI AUG 28 2015
.SHORT TERM...
TONIGHT AND SATURDAY...
250 PM...FORECAST CONCERNS INCLUDE PRECIP COVERAGE/TIMING AND
RAINFALL AMOUNTS.
LOW PRESSURE OVER WESTERN IOWA WILL SLOWLY MOVE EAST TONIGHT AND
EVENTUALLY DISSIPATE OVER NORTHERN ILLINOIS SATURDAY. FIRST WAVE OF
PRECIP IS GENERALLY LIFTING NORTHEAST INTO SOUTHERN WISCONSIN AND
THE MODELS SEEM TO HAVE THIS HANDLED FAIRLY WELL WITH THE HRRR ALSO
SHOWING JUST ISOLATED SHOWERS/SPRINKLES INTO EARLY THIS EVENING AND
MAINLY ACROSS NORTHWEST AND NORTHERN IL. ADDITIONAL PRECIP IS
EXPECTED TO DEVELOP LATER THIS EVENING AND SPREAD NORTHEAST
OVERNIGHT INTO SATURDAY MORNING. THIS PRECIP WILL ALSO BE FOCUSED
ACROSS NORTHWEST/NORTHERN IL...INTO SOUTHERN WI. MODEL QPF AMOUNTS
NEAR THE IL/WI STATE LINE ARE IN THE 1 TO 1.5 INCH RANGE. THESE
AMOUNTS HAVE BEEN CONSISTENT BETWEEN RUNS AND VARIOUS MODELS SO IT
IS LIKELY SOME AREAS WILL SEE OVER AN INCH OF RAIN. HOWEVER...THESE
AMOUNTS APPEAR TO DROP OFF QUICKLY BETWEEN I-88 AND I-80 WITH MUCH
OF THE SOUTHEAST THIRD OR HALF OF THE CWA POSSIBLY STAYING DRY INTO
SATURDAY MORNING. INSTABILITY IS LIMITED AND LIGHTNING HAS BEEN
CONFINED TO THE STRONGEST STORMS/CONVECTION. THUNDER IS CERTAINLY
POSSIBLE TONIGHT BUT OVERALL COVERAGE SHOULD BE LIMITED AND HELD
SLIGHT CHANCE MENTION OF THUNDER TO HIGHER POP AREAS.
AFTER THE MAIN AREA OF RAIN MOVES NORTHEAST SATURDAY MORNING...
PRECIP ACROSS THE REST OF THE CWA WILL BE MORE SCATTERED...OR
ISOLATED...INTO THE LATE MORNING/EARLY AFTERNOON. APPEARS THERE
COULD BE NEW DEVELOPMENT IN THE EARLY/MID AFTERNOON BUT COVERAGE
POSSIBLY STILL JUST SCATTERED. THUS DIDN/T MAKE TOO MANY CHANGES
FROM CURRENT POPS IN THE 40-50 PERCENT RANGE.
TEMPS WILL ONLY SLOWLY FALL INTO THE LOWER/MID 60S TONIGHT AND HIGHS
ON SATURDAY WILL BE DEPENDENT ON PRECIP COVERAGE AND CLOUD COVER.
CURRENT FORECAST OF MID 70S NORTH TO LOWER 80S SOUTHEAST WILL
NEED SOME SUN TO OCCUR. SOUTHEASTERLY WINDS WILL KEEP THE IL SHORE
A BIT COOLER. CMS
&&
.LONG TERM...
344 AM CDT
SUNDAY THROUGH THURSDAY...
END OF THE WEEKEND INTO THE START OF NEXT WEEK WILL SEE THIS
MID/UPPER TROUGH SLOWLY EXITING TO THE EAST...WITH CLOUDS AND
PRECIP CHANCES LIKEWISE EXITING DURING THE DAY SUNDAY. GUIDANCE
VARIES TO THE EVOLUTION OF THIS EXITING SYSTEM BUT LIKELY SCENARIO
FOR OUR AREA WILL BE FOR UPPER LEVEL RIDGING WITH WEAKER FLOW
ALOFT. CONDITIONS WILL LIKELY BE ON THE DRY SIDE THROUGH EARLY
NEXT WEEK...OUTSIDE OF SOME POSSIBLE AFTERNOON THUNDERSTORMS ON
TUESDAY DUE TO INCREASING MOISTURE/INSTABILITY...WHILE A WARMING
TREND CONTINUES.
RODRIGUEZ
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* WIND SHIFT TO EAST-SOUTHEASTERLY LIKELY EARLY THIS EVENING.
* CHANCE OF SHRA/SLIGHT CHANCE OF TS TONIGHT INTO SAT MORNING.
SLIGHTLY BETTER CHANCE OF THUNDER SATURDAY AFTERNOON.
KJB
//DISCUSSION...UPDATED 18Z...
AN ATMOSPHERIC DISTURBANCE...CURRENTLY DRIVING AN AREA OF SHOWERS
AND EMBEDDED STORMS OVER IOWA...WILL GRADUALLY SHIFT EASTWARD
TONIGHT. HOWEVER...IT APPEARS THE MAIN FOCUS FOR SHOWERS AND ANY
STORMS MAY LARGELY REMAIN NORTH OF THE EASTERN TERMINALS...ACROSS
FAR NORTHERN ILLINOIS AND INTO WISCONSIN. BETTER CHANCES OF MORE
SUBSTANTIAL SHOWERS LOOKS TO ENTER THE PICTURE AFTER DAYBREAK
SATURDAY...AND CONTINUING AT TIMES INTO THE AFTERNOON. IT APPEARS
THE THUNDER THREAT WILL BE LOW WITH MUCH OF THIS ACTIVITY.
HOWEVER...THERE WILL BE A SLIGHT BETTER CHANCE OF THUNDER SUNDAY
AFTERNOON AS A FRONTAL ZONE SAGS SOUTHEASTWARD OVER THE AREA.
GIVEN THIS...I HAVE OPTED TO ADD A PROB30 FOR A PERIOD OF THUNDER
LATER SATURDAY AFTERNOON AT THE END OF THE 30 HOUR ORD TAF.
KJB
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH WITH WIND SHIFT TO SOUTHEAST THIS EVENING...LOW WITH PRECISE
SPEEDS AND TIMING.
* MEDIUM WITH PRECIP CHANCES/TIMING...ESPECIALLY SATURDAY
MORNING/EARLY AFTERNOON.
* LOW WITH THREAT OF THUNDER DURING THE PERIOD.
* HIGH CONFIDENCE IN REMAINING FORECAST ELEMENTS.
KJB
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...SLIGHT CHANCE OF TSRA...OTHERWISE VFR.
SUNDAY...VFR. NORTHEAST WINDS.
MONDAY THROUGH THURSDAY...VFR. SOUTHERLY WINDS...POSSIBLE
AFTERNOON WIND SHIFTS TO EASTERLY WITH LAKE BREEZES EACH
AFTERNOON.
IZZI
&&
.MARINE...
157 AM CDT
FAIRLY TYPICAL SUMMER PATTERN LIKELY TO PERSIST THROUGH THE
UPCOMING WEEK WITH GENERALLY NO SIGNIFICANT WINDS/WAVES
ANTICIPATED. WEAK SURFACE LOW OVER THE CORN BELT WILL TRACK SLOWLY
EAST INTO NORTHERN ILLINOIS/SOUTHERN WISCONSIN THROUGH SATURDAY
BEFORE DISSIPATING. THE MAIN RESULT WILL BE A BACKING OF WINDS TO
EASTERLY OVER SOUTHERN PORTIONS OF THE LAKE LATER TODAY INTO THIS
EVENING BEFORE VEERING SOUTHERLY AGAIN LATE TONIGHT AND FRESHENING
UP JUST A BIT...BUT LIKELY LESS THAN 20KT.
IZZI
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS LINCOLN IL
243 PM CDT FRI AUG 28 2015
.SHORT TERM...(TONIGHT)
ISSUED AT 243 PM CDT FRI AUG 28 2015
AFTERNOON SURFACE MAP SHOWING LOW PRESSURE CENTERED NEAR OMAHA, WITH
A WARM FRONT EXTENDING NORTHEAST ACROSS IOWA AND A COLD FRONT INTO
CENTRAL KANSAS. MAIN ACTIVITY OF SHOWERS AND THUNDERSTORMS HAS BEEN
CLOSER TO THE WARM FRONT AND TRACKING NORTH OF OUR FORECAST AREA. A
GENERAL EASTWARD PROGRESSION OF THE BOUNDARIES IS EXPECTED OVER THE
NEXT SEVERAL HOURS, WITH THE COLD FRONT APPROACHING THE
ILLINOIS/IOWA BORDER TOWARD 3-4 AM. FORECAST SOUNDINGS ARE RATHER
DRY BELOW 12,000 FEET FROM ABOUT PEORIA EAST AND SOUTH, AND AM
STARTING TO GET CONCERNED THAT THERE WILL BE LITTLE MORE THAN
ISOLATED SHOWERS BETWEEN I-55 AND THE ILLINOIS RIVER TONIGHT.
HOWEVER, THE HRRR AND ARW MODELS ARE A BIT MORE AGGRESSIVE WITH
SHOWERS MOVING INTO THIS AREA AFTER 3 AM, SO WILL MAINTAIN CHANCE
POP`S ACROSS THE ILLINOIS RIVER VALLEY MAINLY FROM LATE EVENING
THROUGH OVERNIGHT. INSTABILITY IS A LITTLE MORE SPARSE THOUGH, WITH
THE CURRENT THUNDER ACTIVITY MAINLY NEAR THE UPPER LEVEL DISTURBANCE
TRACKING ACROSS CENTRAL IOWA, AND HAVE TRIMMED BACK THE THUNDER
POTENTIAL TO MAINLY WEST OF THE RIVER. OTHERWISE, HAVE MAINLY GONE
DRY EAST OF I-55. MILDER CONDITIONS EXPECTED OVERNIGHT WITH CLOUD
COVER MUCH MORE EXTENSIVE AND A SOUTHERLY FLOW, WITH MOST AREAS
DIPPING INTO THE MID 60S.
&&
.LONG TERM...(SATURDAY THROUGH FRIDAY)
ISSUED AT 243 PM CDT FRI AUG 28 2015
LOW PRESSURE AREA AND ASSOCIATED FRONT WEST OF THE AREA WILL
CONTINUE TO SLOWLY MOVE EAST AND INTO THE CWA DURING THE WEEKEND.
HOWEVER...VERY LITTLE SUPPORT FOR THIS SYSTEM AS IT MOVES EAST SO
ALL MODELS HAVE THIS SYSTEM WEAKENING AS IT MOVES INTO THE AREA.
THEREFORE...WILL ONLY HAVE CHANCE POPS FOR SAT MORNING WEST OF I-55
AND THEN MOVE POPS EAST DURING THE AFTERNOON BUT REMAINING MAINLY
NORTH OF I-70 AS FRONT CONTINUES TO WEAKEN AND BECOME SOMEWHAT
PARALLEL TO THE FLOW AND VERY LACKING ON CONVERGENCE/SUPPORT. CHANCE
POPS FOR SAT NIGHT WILL CONTINUE AS THE UPPER LEVEL WAVE SHIFTS EAST
ACROSS THE AREA. PCPN WILL BE MAINLY SHOWERS AND ISOLATED
THUNDERSTORMS...DUE TO LACK OF FORCING AND INSTABILITY. BY
SUNDAY...THE WAVE SHOULD BE VERY WEAK AND EAST OF THE CWA...SO WILL
ONLY HAVE SLIGHT CHANCE POPS. FOR REMAINDER OF THE WEEKEND AND INTO
THE BEGINNING OF NEXT WEEK...DRY CONDITIONS CAN BE EXPECTED AS HIGH
PRESSURE BEGINS TO BUILD IN THE WEST AND PUSH INTO THE NORTHERN PART
OF THE AREA.
BEGINNING TUE AND THROUGH MOST OF THE WEEK...A COUPLE OF MODELS
BRING REMNANTS OF TS ERIKA INTO THE AREA. HOWEVER...THIS IS
DEPENDENT ON WHERE THE TS GOES. AND IT IS FAR ENOUGH AWAY IN TIME
THAT WILL JUST KEEP CLOSE TO WHAT THE CRINT HAS...AND THAT IS JUST
SLIGHT CHANCE POPS IN SOME AREAS FOR WED THROUGH THUR. SLIGHT CHANCE
POPS WILL BE IN THE GRIDS BUT NOT MENTIONED IN THE WORDED FORECAST.
TEMPS THROUGH THE WEEKEND WILL BE TEMPERED DUE TO CLOUD COVER AND
SCATTERED PCPN...BUT STILL EXPECTING THEM TO RISE INTO THE 80S FOR
THE WEEKEND. BY NEXT WEEK...WITH UPPER LEVEL RIDGING BUILDING INTO
THE AREA AND DEWPOINTS BEING DRIER...EXPECTING TEMPS TO RISE INTO
THE UPPER 80S TO AROUND 90 FOR THE ENTIRE WEEK. THIS WILL BE MUCH
ABOVE NORMAL FOR THE BEGINNING OF SEPT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1227 PM CDT FRI AUG 28 2015
MAIN QUESTION FOR THIS TAF SET WILL BE THE ARRIVAL OF ANY
SHOWERS/STORMS. FORECAST SOUNDINGS ARE SHOWING QUITE A BIT OF DRY
AIR BELOW 10KFT MOST OF THE PERIOD...FINALLY MOISTENING UP AROUND
KPIA TOWARD SUNRISE. HOWEVER...INSTABILITY REMAINS RATHER
LIMITED...SO WILL KEEP MENTION OF THE VCSH THERE WITHOUT ANY
MENTION OF THUNDER. THE REMAINDER OF CENTRAL ILLINOIS WILL MAINLY
SEE A GRADUAL LOWERING OF HIGH CLOUDS THROUGH THE NEXT 24
HOURS...WITH SOUTH-SOUTHEAST WINDS TRENDING MORE SOUTH-SOUTHWEST
BY MID MORNING SATURDAY.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GEELHART
LONG TERM...AUTEN
AVIATION...GEELHART
AREA FORECAST DISCUSSION
NWS DES MOINES IA
358 PM CDT FRI AUG 28 2015
.SHORT TERM /TONIGHT/...
ISSUED AT 358 PM CDT FRI AUG 28 2015
HEAVY RAIN WILL PERSIST ACROSS THE NORTHEAST THROUGH THE
EVENING. LATEST HRRR RUN KEEPS CONVECTION GOING IN THE FAR EAST
THROUGH 04-05Z TIME FRAME AND LEANED TOWARD THIS SOLUTION FOR
POPS/WX. THE WARM RAIN PROCESSES CURRENTLY AFFECTING THE FLASH FLOOD
WARNED AREAS ARE PRODUCING 2-4 INCH PER HOUR RAINFALL RATES. STRONG
DEEP MOISTURE CONVERGENCE OVER THE WATERLOO AREA WITH ROUGHLY 1.5-2
INCH PRECIPITABLE WATER AND WARM CLOUD DEPTHS TO AROUND 4000 METERS
IS ENOUGH TO CONTINUE THE HEAVY RAIN THREAT BEFORE SURFACE LOW IN
WESTERN IOWA PUSHES FURTHER EAST LATER THIS EVENING. POTENTIAL FOR
HEAVY RAIN TO CONTINUE IN THE EAST TO NORTHEAST SECTIONS OF THE
FORECAST AREA THROUGH 03Z TONIGHT...TO COINCIDE WITH THE LATEST HRRR
THINKING. OTHER CONCERN IS FOG OVERNIGHT WITH PLENTY OF MOISTURE AND
VERY LITTLE FLOW AT THE SURFACE A WEAK SURFACE RIDGE BUILDS INTO
WESTERN IOWA. HAVE MENTIONED PATCHY FOG PAST 09Z WEST OF I-35.
.LONG TERM /SATURDAY THROUGH FRIDAY/...
ISSUED AT 358 PM CDT FRI AUG 28 2015
THE WEATHER WILL GENERALLY BE QUIET IN THE LONGER TERM WITH UPPER
RIDGING BUILDING INTO THE CENTRAL UNITED STATES. THICKNESSES WILL
INCREASE WITH TEMPERATURES CORRESPONDINGLY RESPONDING WITH HIGHS
CLIMBING ABOVE NORMAL...LIKELY TOWARD 90 BY EARLY NEXT
WEEK...ESPECIALLY IN THE SOUTH AND WEST. BOTH GFS AND EURO
INDICATED A WEAK SYSTEM PULLING NORTHEAST ON TUESDAY INTO THE
PLAINS WHICH MAY BRING THE THREAT OF ISOLATED THUNDER INTO THE
NORTHWEST PORTIONS OF IOWA BY LATER IN THE DAY INTO TUESDAY NIGHT.
OTHERWISE...THE RIDGE WILL REMAIN IN PLACE INTO LATE IN THE WEEK
WITH THE VERY WARM TEMPERATURES AND LITTLE THREAT OF PRECIPITATION.
&&
.AVIATION...28/18Z
ISSUED AT 105 PM CDT FRI AUG 28 2015
IFR TO MVFR STRATUS WILL PERSIST THROUGH THE AFTERNOON AND INTO
THE OVERNIGHT HOURS. MCW/ALO HAVE THE BEST SHOT OF IFR VIS WRT TO
HEAVY RAIN THIS AFTERNOON. OTHERWISE...EXPECTING FOG/STRATUS TO
CONTINUE OVERNIGHT INTO SATURDAY MORNING AND HAVE MENTION OF IFR
CONDITIONS PAST 06Z SATURDAY.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...PODRAZIK
LONG TERM...COGIL
AVIATION...PODRAZIK
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
412 PM EDT FRI AUG 28 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 411 PM EDT FRI AUG 28 2015
WV IMAGERY AND RAP ANALYSIS INDICATED MAINLY ZONAL MID/UPPER LEVEL
FLOW ALONG THE US/CANADIAN BORDER. A SHORTWAVE TROUGH FROM NW
ONTARIO INTO NRN MN SUPPORTED SCT SHRA/TSRA OVER THE MN ARROWHEAD
INTO NRN ONTARIO WEST OF THUNDER BAY. TO THE SOUTH...ANOTHER SHRTWV
OVER IA BRINGING SHOWERS FROM NE IA THROUGH SW WI WAS SLOWLY LIFTING
TO THE ENE. THE LEADING EDGE OF THE PCPN TO NEAR AUW.
OTHERWISE...PARTLY TO MOSTLY CLOUDY SKIES PREVAILED ACROSS UPPER MI
WITH TEMPS IN THE MID 70S.
TONIGHT...MOST OF THE CWA WILL REMAIN BETWEEN THE INFLUENCE OF THE
NRN AND SRN STREAM SHORTWAVES. RADAR TRENDS AND SHORT RANGE MODELS
SUGGEST THAT THE RAIN OVER WI TO AFFECT MAINLY THE SRN TIER ALONG
AND SOUTH OF US-2 FROM IMT EASTWARD. SHRA/TSRA WITH THE NRN STREAM
SHRTWV MAY BRUSH MAINLY THE KEWEENAW BY LATE THIS EVENING AND
POSSIBLY INTO THE NRN PORTION OF UPPER MI. FCST MUCAPE VALUES INTO
THE 500-1000 J/KG RANGE OVER THE NORTH COULD ALSO SUPPORT ISOLD
TSRA.
SATURDAY...SOME SHOWERS MAY LINGER OVER THE SE PORTION OF THE CWA
ASSOCIATED WITH REMNANTS OF THE WI SHRTWV OR POSSIBLY AIDED BY A
TRAILING SHRTWV DIVING INTO NRN WI. HOWEVER...EXPECT THE PCPN TO
SLIDE OFF TO THE EAST BY AFTERNOON. WITH SOME CLEARING INTO THE WEST
HALF BY AFTERNOON...TEMPS WILL REBOUND INTO THE MID AND UPPER 70.
GREATER CLOUD COVER OVER THE EAST AND WITH SRLY FLOW OFF OF LAKE
MI...TEMPS WILL REMAIN IN UPPER 60S AND LOWER 70S.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 344 PM EDT FRI AUG 28 2015
COULD SEE A FEW SHOWERS IN THE FIRST 6 HOURS OF THE FORECAST SAT
NIGHT...BUT THINK VAST MAJORITY OF PRECIP ASSOCIATED WITH A
SHORTWAVE WILL BE OUT OF THE AREA. OTHERWISE...PRECIP CHANCES ARE
LOW IN THE LONG TERM AS A MID-UPPER RIDGE MOVES IN AND SITS OVER THE
CENTRAL TO ERN CONUS. COULD SEE SOME PRECIP MID-LATE NEXT WEEK AS
SHORTWAVES TRY TO TOP THE RIDGE...BUT PREDICTABILITY IS TOO LOW TO
JUSTIFY ANYTHING ABOVE SLIGHT CHANCE POPS.
TEMPS WILL BE ON THE INCREASE AND WILL ALREADY BE ABOVE NORMAL SUN.
HIGHS SUN WILL BE IN THE MID 70S TO LOW 80S AS 850MB TEMPS START OUT
IN THE MID TEENS C. 850MB TEMPS THROUGH THE REST OF THE WEEK WILL BE
AROUND 20C...RESULTING IN HIGH TEMPS 10 OR MORE DEGREES ABOVE
NORMAL.
COULD SEE SOME PATCHY FOG AROUND SAT NIGHT INTO EARLY SUN MORNING
AND AGAIN SUN NIGHT INTO MON MORNING AS HIGH PRESSURE/SUBSIDENCE
MOVES IN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 141 PM EDT FRI AUG 28 2015
MVFR CIGS AT CMX ARE EXPECTED TO GIVE WAY TO VFR CONDITIONS BY LATE
THIS AFTERNOON. THERE IS ALSO SLIGHT CHANCE FOR SHOWERS AT CMX...BUT
PROB IS TOO LOW TO INCLUDE IN THE TAF. OTHERWISE...VFR CONDITIONS
WILL CONTINUE THROUGH THIS FCST PERIOD AT KIWD/KSAW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 411 PM EDT FRI AUG 28 2015
EXPECT A PERIOD OF MODERATE SW WINDS LATE TONIGHT INTO EARLY GUSTING
TO 15-20 KNOTS. OTHERWISE...A GENERALLY WEAK PRES GRADIENT WILL
DOMINATE THE UPPER LAKES INTO EARLY NEXT WEEK. ON MOST DAYS...WINDS
WILL BE UNDER 15KT. LOOKS LIKE THE LIGHTEST WINDS WILL OCCUR OVER THE
WEEKEND WITH HIGH PRES RIDGE MORE FIRMLY IN CONTROL.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
523 PM CDT FRI AUG 28 2015
.SHORT TERM: (THROUGH LATE TONIGHT)
ISSUED AT 315 PM CDT FRI AUG 28 2015
WATER VAPOR IMAGERY SHOWS THAT A SHORTWAVE TROUGH IS MOVING SLOWLY
EAST ACROSS MISSOURI AT THIS HOUR. LATEST RUNS OF THE RAP SUGGEST
THAT IT WILL TAKE ALL EVENING FOR THIS FIRST SHORTWAVE TO REACH
HALFWAY ACROSS THE CWA WHILE A SECOND SHORTWAVE WILL ENTER WESTERN
MISSOURI BEHIND IT LATER TONIGHT. LOW LEVEL MOISTURE CONVERGENCE
WILL INCREASE ACROSS EASTERN MISSOURI BY LATER THIS EVENING AS LOW
LEVEL JET VEERS AND INCREASES IN SPEED SLIGHTLY. THIS SHOULD CAUSE
AN INCREASE IN COVERAGE IN SCATTERED SHOWERS AND THUNDERSTORMS BY
LATE EVENING AND OVERNIGHT OVER THE REGION BECAUSE OF THE FORCING
FROM THE SHORTWAVES AND THE MOISTURE CONVERGENCE. THE 1KM
REFLECTIVITY FROM THE CAMS DEPICTS THIS PRETTY WELL.
MOS LOWS TONIGHT LOOK REASONABLE GIVEN THE INCREASING DEWPOINTS
AHEAD OF THE COLD FRONT CURRENTLY OVER THE CENTRAL PLAINS.
BRITT
.LONG TERM: (SATURDAY THROUGH NEXT FRIDAY)
ISSUED AT 316 PM CDT FRI AUG 28 2015
AT LEAST SCATTERED SHOWERS AND THUNDERSTORMS CAN BE EXPECTED ON
SATURDAY AND SATURDAY EVENING AS AN UPPER LEVEL TROUGH MOVES
SLOWLY SOUTHEASTWARD THROUGH OUR AREA. IT NOW APPEARS THAT THE
COLD FRONT WILL ONLY MAKE IT INTO NORTHEAST MO AND WEST CENTRAL IL
BEFORE GRADUALLY DISSIPATING. ONLY SLIGHT COOLING IS EXPECTED
ACROSS NORTHEAST MO AND WEST CENTRAL IL SATURDAY AND SATURDAY
NIGHT WITH THE REST OF THE AREA SLIGHTLY WARMER AND MORE HUMID
DESPITE THE CLOUD COVER ON SATURDAY WITH MAINLY A WEAK SOUTHERLY
FLOW. ALTHOUGH THE CHANCE OF PRECIPITATION WILL LESSEN BY LATE
SATURDAY NIGHT AND SUNDAY...THERE MAY STILL BE AT LEAST ISOLATED
SHOWERS/STORMS ACROSS MAINLY SOUTHEAST MO AND SOUTHWEST IL AS THE
WEAKENING UPPER LEVEL TROUGH...SHEAR AXIS MOVES ONLY SLOWLY
SOUTHEASTWARD. A WAMER PERIOD OF WEATHER IS FORECAST FOR THE NEXT
WORK WEEK DUE TO PERSISTENT SOUTHERLY SURFACE/LOW LEVEL FLOW WITH
THE SURFACE/850 MB RIDGE EAST/SOUTHEAST OF OUR AREA...AND AT
LEAST UPPER LEVEL RIDGING ACROSS NORTHWEST MO. WILL KEEP THE
REMAINDER OF THE FORECAST DRY FOR NOW...ALTHOUGH COULD NOT RULE
OUT A FEW SHOWERS/STORMS MAINLY DURING THE AFTERNOON AND EARLY
EVENING HOURS AS THE MODELS CONTINUE TO DEPICT SOME WEAK MID-UPPER
LEVEL TROUGHING...SHEAR AXIS ACROSS MAINLY SOUTHEAST MO AND
SOUTHWEST IL.
GKS
&&
.AVIATION: (FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 519 PM CDT FRI AUG 28 2015
SLOW MOVING TROF OF LOW PRESSURE AND SEVERAL UPPER AIR
DISTURBANCES WILL BRING SCATTERED SHOWERS AND THUNDERSTORMS TO THE
REGION TONIGHT THROUGH SATURDAY NIGHT. EXPECT VFR CONDITIONS
OUTSIDE OF ANY HEAVIER SHOWERS THAT COULD TEMPORARILY REDUCE
THE VISIBILITY AND CEILING AT A TERMINAL. LIGHT SOUTHEAST/SOUTH
WIND EXPECTED TO CONTINUE THROUGH THE PERIOD.
SPECIFICS FOR KSTL:
SCATTERED SHOWERS SHOULD ARRIVE NEAR THE TERMINAL COMPLEX AROUND
12Z WITH THE THREAT OF SCATTERED THUNDERSTORMS DEVELOPING DURING
THE HEAT OF THE DAY...OR AFTERNOON. CONFIDENCE IN COVERAGE OF RAIN
IS NOT HIGH ENOUGH TO INCLUDE IN THE FORECAST OUTSIDE OF VICINITY
AT THIS TIME. LIGHT SOUTHEAST TO SOUTH WIND EXPECTED TO CONTINUE
THROUGH THE PERIOD.
CVKING
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
409 PM CDT FRI AUG 28 2015
.DISCUSSION...
Issued at 409 PM CDT FRI AUG 28 2015
Tonight...
Positive tilted shortwave trough as noted in satellite imagery from
IA through KS will slide east tonight. Scattered convection will
form along an associated cold front within a moderately
unstable airmass....at least it will be into the early evening
hours.
A narrow band of convection has finally formed over east
central KS where MLCAPES between 1500-2000J/kg are noted. Further
northeast VFR ceilings within the warm sector have pretty much
capped intense convection as radar shows sputtering area of low
topped showers. The east central KS activity may be the only region
which develops deep convection, albeit the non-severe variety. Will
hit PoPs highest over northern and west central counties until a few
hours after sunset. Thereafter expect a fairly quick drop off in
intensity and coverage as instability hits the skids. Believe the
trend of the HRRR and 12z NAM looks reasonable. QPF will also be
muted. Could see isolated showers form after the passage of the
frontal convection and last into the pre-dawn hours.
Saturday - Sunday...
The above shortwave is expected to flounder over the Mid MO Valley
over the weekend. The h7 shortwave trough will be slow to exit the
CWA resulting in a general region of uvv over the eastern 1/2 of the
CWA. Thinking there will be sufficient breaks in the overcast such
that isolated instability showers/storms will be possible Saturday
afternoon over parts of northeast and central MO. Current
temperature forecast may be a bit too optimistic should the
afternoon clouds fail to break up.
Sunday looks dry with a slight warm-up as the mid level trough
washes out.
Monday - Friday...
The operational models transition to a broadening southwesterly flow
pattern after the upper level ridge axis leans over into the Central
Plains. This will allow warmer more seasonal temperatures and
humidity back into the region. While the h7 temperatures don`t get
overly hot and cap off the environment a lack of any discernible
mid/upper level wave or surface boundaries will greatly limit the
rain chances. As such will go with a dry forecast until some feature
of significance is picked up by the models.
&&
.AVIATION...(For the 18Z TAFS through 18Z Saturday Afternoon)
Issued at 1253 PM CDT FRI AUG 28 2015
Isolated light afternoon showers east of I-35. VFR conditions through
the afternoon hours. Otherwise, scattered convection expected to form
by late afternoon over northwest MO and northeast KS along or just
ahead of a cold front. Activity expected to advance southeast through
the early evening hours but weaken after sunset. Except for a brief
period of MVFR ceilings with the strongest storms over northwest MO
expect VFR ceilings. Timing remains too uncertain for a 2hr TEMPO
group for the Kansas City terminals.
Should see MVFR ceilings follow with the passage of the cold front.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
DISCUSSION...MJ
AVIATION...MJ
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
344 PM CDT FRI AUG 28 2015
.SHORT TERM: (THROUGH LATE TONIGHT)
ISSUED AT 315 PM CDT FRI AUG 28 2015
WATER VAPOR IMAGERY SHOWS THAT A SHORTWAVE TROUGH IS MOVING SLOWLY
EAST ACROSS MISSOURI AT THIS HOUR. LATEST RUNS OF THE RAP SUGGEST
THAT IT WILL TAKE ALL EVENING FOR THIS FIRST SHORTWAVE TO REACH
HALFWAY ACROSS THE CWA WHILE A SECOND SHORTWAVE WILL ENTER WESTERN
MISSOURI BEHIND IT LATER TONIGHT. LOW LEVEL MOISTURE CONVERGENCE
WILL INCREASE ACROSS EASTERN MISSOURI BY LATER THIS EVENING AS LOW
LEVEL JET VEERS AND INCREASES IN SPEED SLIGHTLY. THIS SHOULD CAUSE
AN INCREASE IN COVERAGE IN SCATTERED SHOWERS AND THUNDERSTORMS BY
LATE EVENING AND OVERNIGHT OVER THE REGION BECAUSE OF THE FORCING
FROM THE SHORTWAVES AND THE MOISTURE CONVERGENCE. THE 1KM
REFLECTIVITY FROM THE CAMS DEPICTS THIS PRETTY WELL.
MOS LOWS TONIGHT LOOK REASONABLE GIVEN THE INCREASING DEWPOINTS
AHEAD OF THE COLD FRONT CURRENTLY OVER THE CENTRAL PLAINS.
BRITT
.LONG TERM: (SATURDAY THROUGH NEXT FRIDAY)
ISSUED AT 316 PM CDT FRI AUG 28 2015
AT LEAST SCATTERED SHOWERS AND THUNDERSTORMS CAN BE EXPECTED ON
SATURDAY AND SATURDAY EVENING AS AN UPPER LEVEL TROUGH MOVES
SLOWLY SOUTHEASTWARD THROUGH OUR AREA. IT NOW APPEARS THAT THE
COLD FRONT WILL ONLY MAKE IT INTO NORTHEAST MO AND WEST CENTRAL IL
BEFORE GRADUALLY DISSIPATING. ONLY SLIGHT COOLING IS EXPECTED
ACROSS NORTHEAST MO AND WEST CENTRAL IL SATURDAY AND SATURDAY
NIGHT WITH THE REST OF THE AREA SLIGHTLY WARMER AND MORE HUMID
DESPITE THE CLOUD COVER ON SATURDAY WITH MAINLY A WEAK SOUTHERLY
FLOW. ALTHOUGH THE CHANCE OF PRECIPITATION WILL LESSEN BY LATE
SATURDAY NIGHT AND SUNDAY...THERE MAY STILL BE AT LEAST ISOLATED
SHOWERS/STORMS ACROSS MAINLY SOUTHEAST MO AND SOUTHWEST IL AS THE
WEAKENING UPPER LEVEL TROUGH...SHEAR AXIS MOVES ONLY SLOWLY
SOUTHEASTWARD. A WAMER PERIOD OF WEATHER IS FORECAST FOR THE NEXT
WORK WEEK DUE TO PERSISTENT SOUTHERLY SURFACE/LOW LEVEL FLOW WITH
THE SURFACE/850 MB RIDGE EAST/SOUTHEAST OF OUR AREA...AND AT
LEAST UPPER LEVEL RIDGING ACROSS NORTHWEST MO. WILL KEEP THE
REMAINDER OF THE FORECAST DRY FOR NOW...ALTHOUGH COULD NOT RULE
OUT A FEW SHOWERS/STORMS MAINLY DURING THE AFTERNOON AND EARLY
EVENING HOURS AS THE MODELS CONTINUE TO DEPICT SOME WEAK MID-UPPER
LEVEL TROUGHING...SHEAR AXIS ACROSS MAINLY SOUTHEAST MO AND
SOUTHWEST IL.
GKS
&&
.AVIATION: (FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1237 PM CDT FRI AUG 28 2015
EXPECT MAINLY DRY AND VFR CONDITIONS THROUGH THIS EVENING. THEN
EXPECT SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP ACROSS
CENTRAL AND NORTHEAST MISSOURI AND WEST CENTRAL ILLINOIS OVERNIGHT
THAT WILL EVENTUALLY SPREAD INTO THE ST. LOUIS METRO AREA ON
SATURDAY MORNING. SCATTERED THUNDERSTORMS WILL CONTINUE TO DEVELOP
ON SATURDAY AFTERNOON AROUND THE ST. LOUIS METRO TAF SITES.
SPECIFICS FOR KSTL: EXPECT MAINLY DRY AND VFR CONDITIONS THROUGH
TONIGHT. THEN SCATTERED SHOWERS WILL MOVE INTO THE AREA BY LATE
SATURDAY MORNING WITH AN INCREASING CHANCE OF SCATTERED
THUNDERSTORMS AS AN UPPER LEVEL STORM SYSTEM MOVES INTO THE AREA
BY LATE SATURDAY AFTERNOON.
BRITT
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
316 PM CDT FRI AUG 28 2015
.SHORT TERM: (THROUGH LATE TONIGHT)
ISSUED AT 315 PM CDT FRI AUG 28 2015
WATER VAPOR IMAGERY SHOWS THAT A SHORTWAVE TROUGH IS MOVING SLOWLY
EAST ACROSS MISSOURI AT THIS HOUR. LATEST RUNS OF THE RAP SUGGEST
THAT IT WILL TAKE ALL EVENING FOR THIS FIRST SHORTWAVE TO REACH
HALFWAY ACROSS THE CWA WHILE A SECOND SHORTWAVE WILL ENTER WESTERN
MISSOURI BEHIND IT LATER TONIGHT. LOW LEVEL MOISTURE CONVERGENCE
WILL INCREASE ACROSS EASTERN MISSOURI BY LATER THIS EVENING AS LOW
LEVEL JET VEERS AND INCREASES IN SPEED SLIGHTLY. THIS SHOULD CAUSE
AN INCREASE IN COVERAGE IN SCATTERED SHOWERS AND THUNDERSTORMS BY
LATE EVENING AND OVERNIGHT OVER THE REGION BECAUSE OF THE FORCING
FROM THE SHORTWAVES AND THE MOISTURE CONVERGENCE. THE 1KM
REFLECTIVITY FROM THE CAMS DEPICTS THIS PRETTY WELL.
MOS LOWS TONIGHT LOOK REASONABLE GIVEN THE INCREASING DEWPOINTS
AHEAD OF THE COLD FRONT CURRENTLY OVER THE CENTRAL PLAINS.
BRITT
.LONG TERM: (TONIGHT THROUGH THURSDAY)
ISSUED AT 340 AM CDT FRI AUG 28 2015
THERE IS GOOD AGREEMENT IN THE 00Z GUIDANCE THAT FRONTAL
BOUNDARY AND ASSOCIATED SHORTWAVE SHOULD ALLOW THUNDERSTORMS
THREAT TO SLOWLY EXPAND OVER THE NORTHWEST HALF OF THE CWA
TONIGHT...WITH THE STL METRO LIKELY ON THE EASTERN EDGE OF THE
THREAT DURING THE PREDAWN HOURS. DUE TO PROGGED LOW LEVEL
FORCING AHEAD OF THE FRONT, HAVE UPPED POPS INTO LIKELY CATEGORY
OVER OUR EXTREME NORTHWEST COUNTIES.
HOWEVER...FROM SATURDAY MORNING ON FEATURES AND MODEL SPECIFICS
BEGIN TO DIVERGE AND BECOME INCREASING NEBULOUS. WHILE MODELS DO
AGREE THAT NORTHERN PORTION OF THE SHORTWAVE WILL CONTINUE TO PRESS
INTO THE LOWER GREAT LAKES DURING THE DAY...THEY DISAGREE WITH THEIR
HANDLING OF THE SOUTHERN PORTION OF THE SHORTWAVE ENERGY AS IT
STRETCHES SOUTHEAST AND POSSIBLY MERGING WITH ANOTHER WEAK
CIRCULATION ALONG THE GULF COAST (WHICH APPEARS TO ORIGINATE WITH
A BIT OF ENERGY THAT BREAKS OFF FROM THE BASE OF THE CURRENT EAST
COAST TROF). GFS AND NAM SUGGEST SOME TYPE OF REMNANT CIRCULATION
TAKING UP RESIDENCE IN THE VICINITY OF SW MO BY SUNDAY WITH
RESIDUAL SURFACE FRONT BECOMING STATIONARY OVER THE AREA...WHILE
ECMWF WANTS TO PUSH THE INCREASINGLY WEAK SHORTWAVE ENERGY AND
SURFACE BOUNDARY SOUTH WITH TIME.
IF NAM AND GFS SOLUTIONS DO COME TO FRUITION ON SUNDAY...AND IF NAM
LOW LEVEL MOISTURE FORECAST (WHICH IS OFTEN TOO HIGH) ALSO
VERIFIES...THEN THE DRY FORECAST ON SUNDAY WILL BE IN JEOPARDY.
HOWEVER...WOULD LIKE TO SEE ADDITIONAL SUPPORT FOR THESE WEAK
FEATURES AND TRENDS BEFORE REINTRODUCING CONVECTION ON SUNDAY. SO
FOR NOW HAVE CONTINUED TO TREND THE FORECAST TO THE ECMWF
SOLUTION...NAMELY THUNDERSTORM CHANCES EXPANDING SOUTHEAST ACROSS
THE CWA DURING THE DAY ON SATURDAY THEN GRADUALLY DIMINISHING FROM
NW TO SE LATE SATURDAY AFTERNOON AND SATURDAY NIGHT.
DESPITE THE DISCREPANCY IN THE UA PROGS ON SUNDAY...MEDIUM RANGE
SOLUTIONS REMAIN IN GOOD RUN TO RUN AND MODEL TO MODEL AGREEMENT
THAT WESTERN RIDGE WILL BE EXPANDING EAST INTO THE MID
MISSISSIPPI AND OHIO VALLEYS DURING THE UPCOMING WEEK. THIS SHOULD
MEAN DRY WEATHER FOR THE FA...ALONG WITH TEMPERATURES REBOUNDING
TO LATE SUMMER LEVELS WITH HIGHS IN THE UPPER 80S-LOWER 90S.
TRUETT
&&
.AVIATION: (FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1237 PM CDT FRI AUG 28 2015
EXPECT MAINLY DRY AND VFR CONDITIONS THROUGH THIS EVENING. THEN
EXPECT SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP ACROSS
CENTRAL AND NORTHEAST MISSOURI AND WEST CENTRAL ILLINOIS OVERNIGHT
THAT WILL EVENTUALLY SPREAD INTO THE ST. LOUIS METRO AREA ON
SATURDAY MORNING. SCATTERED THUNDERSTORMS WILL CONTINUE TO DEVELOP
ON SATURDAY AFTERNOON AROUND THE ST. LOUIS METRO TAF SITES.
SPECIFICS FOR KSTL: EXPECT MAINLY DRY AND VFR CONDITIONS THROUGH
TONIGHT. THEN SCATTERED SHOWERS WILL MOVE INTO THE AREA BY LATE
SATURDAY MORNING WITH AN INCREASING CHANCE OF SCATTERED
THUNDERSTORMS AS AN UPPER LEVEL STORM SYSTEM MOVES INTO THE AREA
BY LATE SATURDAY AFTERNOON.
BRITT
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1238 PM CDT FRI AUG 28 2015
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 305 AM CDT FRI AUG 28 2015
PCPN CHANCES TODAY AND THEN TEMPERATURES THE NEXT FEW DAYS WILL BE
THE MAIN FORECAST CONCERNS.
FAIRLY WIDESPREAD AREA OF SHRA AND TSRA WILL CONTINUE TO MOVE EAST
THIS MORNING...ASSOCIATED WITH SHORTWAVE TROUGH MOVING THROUGH THE
REGION. WATER VAPOR SATELLITE IMAGERY LOOP IN COMBINATION WITH
RECENT 500 MB RUC MODEL INITIALIZATIONS SHOWED A FAIRLY STRONG
WAVE FOR THIS TIME OF YEAR. 12 HOUR HEIGHT FALLS AT 500 MB WERE UP
TO ABOUT 50 METERS. ATMOSPHERE WAS ALSO QUITE MOIST. 700 MB
DEWPOINTS OF 4-8 DEGREES C WERE NOTED FROM THE DESERT SW UP INTO
WRN KS AND SWRN NE AT 00Z LAST EVENING...AND FORECAST SOUNDINGS
SUGGEST PW VALUES ARE AROUND 2 INCHES OR MORE EARLY THIS MORNING.
ALTHOUGH THE STRONGEST AREA OF LIFT AND HIGHEST MOISTURE WILL BE
SHIFTING EAST OF THE LOCAL AREA...KEPT SOME POPS GOING MUCH OF THE
DAY. A WEAKER AREA OF LIFT SHOULD SPREAD SEWD OVER THE REGION AND
FORECAST SOUNDINGS STILL SHOW SOME INSTABILITY. WILL KEEP RAIN
CHANCES MAINLY AT 20-30 PERCENT AFTER EARLY MORNING ACTIVITY ENDS.
RECENT HRRR RUNS AND EVEN THE 00Z NAM SUGGEST PREVIOUS SCENARIO...
WITH AT LEAST ISOLD SHRA/TSRA POSSIBLE.
LINGERED A SLIGHT CHANCE OF TSRA IN OUR FAR SERN ZONES EARLY THIS
EVENING...THEN IT SHOULD BE MAINLY DRY THROUGH SUNDAY. KEPT SOME
MENTION OF FOG TONIGHT WITH LIGHT WINDS AND BOTH GFS MOS AND NAM
MOS SUGGESTING AT LEAST PATCHY FOG LATE TONIGHT INTO SAT MORNING.
DID NOT MENTION FOG SATURDAY NIGHT...BUT SFC RIDGE AXIS WILL BE
CLOSE TO THE AREA AND WILL NEED TO MONITOR. RETURN FLOW WITH S/SE
SFC WINDS SHOULD THEN STRENGTHEN SUNDAY.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 305 AM CDT FRI AUG 28 2015
MID LEVEL RIDGE EXTENDING FROM NWRN MEXICO UP INTO THE CNTRL
PLAINS AND A TROUGH FROM WRN CANADA INTO THE NWRN UNITED STATES
WILL BE THE MAIN FEATURES AT THE START OF THIS PERIOD. RIDGE WILL
SLIDE SLOWLY SEWD AS THE TROUGH TO THE NORTHWEST DIGS. WEAK RIPPLES
MOVING NEWD THROUGH THE REGION COULD BRING SOME TSRA...WITH BEST
CHANCES BEING TUE NIGHT AND AGAIN THU NIGHT.
TEMPERATURES SHOULD BE AT OR ABOVE NORMAL OVER THE AREA FOR MOST
OR ALL OF NEXT WEEK.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1230 PM CDT FRI AUG 28 2015
CEILINGS HAD TRENDED TO MVFR AT ALL THREE TAF SITES AS OF 17Z.
THOUGH SOME PATCHY IFR CIGS LINGER NORTH OF KOFK IN SOUTH
DAKOTA...LIFTING AND THINNING OF CIGS SHOULD CONTINUE THROUGH 00Z.
THEN AS HIGH PRESSURE SETTLES IN ACROSS THE REGION
OVERNIGHT...WINDS WILL GO LIGHT AND COMBINED WITH RECENT RAIN AND
SURFACE MOISTURE EXPECT IFR VISIBILITIES AND CIGS TO SET IN AFTER
10Z AT ALL THREE TAF SITES. AFTER 16Z CONDITIONS WILL IMPROVE TO
MVFR TO VFR.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...MEYER
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
145 PM EDT FRI AUG 28 2015
.SYNOPSIS...
A WEAK FRONT WILL MEANDER OFF THE THE COAST AS HIGH PRESSURE
SLOWLY BUILDS INTO THE CAROLINAS OVER THE WEEKEND. ERIKA IS
EXPECTED TO APPROACH THE BAHAMAS AND SOUTH FLORIDA LATE IN THE
WEEKEND TRACKING THROUGH FLORIDA INTO EARLY NEXT WEEK...AND
POSSIBLY REMAINING ON A MORE WESTWARD TRACK CLOSER TO THE GULF
COAST.
&&
.NEAR TERM /THROUGH TONIGHT/... AS OF 1015 AM FRIDAY...HAVE SLIGHTLY
CONTINUED THE DOWNWARD TREND IN SKY COVER AND TEMPTED TO DO THE SAME
WITH RAIN CHANCES. NEITHER THE 12KM WRF, HRRR, OR RUC BRING ANYTHING
MEASURABLE ONSHORE. WILL WAIT ONE MORE CYCLE TO MONITOR CU
DEVELOPMENT AS WELL AS FORMATION OF NE RESULTANT SEABREEZE THAT MAY
GRAB AN OFFSHORE SHOWER AND FLING IT ASHORE. BEST CHANCE WOULD BE
BALD HEAD ISLAND/SOUTHPORT AREAS. PREVIOUS DISCUSSION FOLLOWS:
AS OF 650 AM FRIDAY...HAVE STAYED WITH A DRIER BIAS FOR THIS NEAR
TERM FORECAST...AND KEPT THE THREAT FOR LOW CHANCE POPS ACROSS THE
COASTAL COUNTIES WITH DIURNALLY DRIVEN CONVECTION THE MAIN
EMPHASIS FROM LATE THIS MORNING THRU EARLY THIS EVENING.
LATEST WATER VAPOR IMAGERY INDICATES A MUCH DRIER PICTURE COMPARED
THIS TIME YESTERDAY MORNING. PROGGED MODEL SOUNDINGS INDICATE DRY
AIR BETWEEN 350 MB AND 900 MB BECOMING MORE DOMINANT ACROSS THE FA
LATER THIS MORNING THRU TONIGHT AND INTO THE SHORT TERM PERIOD.
THE SOMEWHAT STALLED SFC BOUNDARY ORIENTED NE-SW AND PARALLEL TO
THE ILM CWA COASTLINE...WILL DRIFT SLIGHTLY FURTHER OFFSHORE THIS
PERIOD. THIS HAS ALREADY ALLOWED THE MODEST 1020+ SFC HIGH
BROADLY CENTERED OVER THE NE STATES AND MID-ATLANTIC TO RIDGE OR
NOSE SOUTH-SOUTHWESTWARD PUSHING DRIER AIR AND LOWER SFC DEWPOINTS
TO AND ACROSS THE ILM CWA. ALREADY OBSERVING WIDESPREAD 60S
DEWPOINTS ACROSS THE FA...ALL THE WAY TO THE IMMEDIATE COAST.
MODELS INDICATE POSSIBLY AROUND 60 THIS AFTN ACROSS THE
NORTHERNMOST PORTIONS OF THE FA THIS AFTN WHERE MIXING OF DRIER
AIR ALOFT TO THE SFC MAY OCCUR. WITH ALL THIS SAID...THE BEST
FORCING/LIFT FOR CONVECTION WILL INITIALLY START JUST ALONG AND
OFF THE IMMEDIATE COAST...AND SWITCH FURTHER EAST AND FURTHER OFF
THE MAINLAND AS THE BOUNDARY LAYER ASSOCIATED WITH THE STALLED SFC
FRONT DRIFTS EASTWARD.
HAVE ALSO GONE WITH OVERALL LESS CLOUD COVERAGE...ESPECIALLY
TONIGHT WHERE ANY DEBRIS CONVECTIVE CLOUDS WILL EITHER STAY
WITHIN THE MEAN FLOW OVER THE ATL WATERS...OR THE DEBRIS CLOUDS
THAT PUSH N-NE FROM GA WILL SCOUR OUT A GOOD DEAL PRIOR TO PUSHING
ACROSS THE FA.
AS FOR TEMPS...LOOKING AT WIDESPREAD 80S FOR MAX TEMPS
TODAY...AND WIDESPREAD 60S FOR MINS EXCEPT NEAR 70 ALONG THE
IMMEDIATE COAST AND EXTREME SOUTHERN PORTIONS OF THE FA. STAYED
WITH A SLIGHTLY COOLER BIAS FOR TONIGHTS MINS USING THE LATEST
AVBL MODEL MOS GUIDANCE.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 330 AM FRIDAY...DRY AIR CONTINUES TO FUNNEL INTO THE AREA
IN NORTHERLY FLOW ON BACK END OF LINGERING FRONT/TROUGH/OFF SHORE
ON SAT. A WAVE OF LOW PRESSURE DEVELOPS ALONG THE FRONT AND LIFTS
OFF TO THE NORTHEAST THROUGH LATE SAT INTO SUN LEAVING WEAK HIGH
PRESSURE OVER THE AREA THROUGH SUN NIGHT. THE NORTHERLY FLOW
BETWEEN HIGH PRESSURE INLAND AND LOW OFF SHORE ON SAT WILL BEGIN
TO VEER AROUND BECOMING MORE ON SHORE THROUGH SUNDAY. ABOVE THE
SURFACE...LOW PRESSURE ALOFT OVER THE CENTRAL GULF COAST WILL
BEGIN TO MOVE SLOWLY NORTHEAST AND WEAKEN PROVIDING A STEADY
SOUTHERLY FLOW OF MOISTURE INTO THE CAROLINAS IN THE LOW TO MID
LEVELS SAT NIGHT INTO SUNDAY. THIS IS DEPICTED WELL BY THE
MOISTURE PROFILES AND GUIDANCE SHOWING A DEEPENING OF MOISTURE
THROUGH THE COLUMN AND AN INCREASE IN CLOUD COVER ON SUNDAY. WITH
SUCH DRY AIR IN PLACE IN THE BEGINNING OF PERIOD...EXPECT LIMITED
TO NO SHWR ACTIVITY WITH A FEW SHWRS/TSTMS POSSIBLE IN LOCALIZED
CONVERGENCE MAINLY ASSOCIATED WITH THE SEA BREEZE OVER THE
WEEKEND...WITH MAINLY SOME HIGHER LEVEL CLOUDS AROUND. PCP WATER
VALUES DOWN LESS THAN AN INCH OVER INLAND NORTH CAROLINA INCREASE
UP TO 1.25 INCHES BY SAT EVE AND UP CLOSE TO 1.5 TO 1.75 INCHES
BY SUN AFTN IN A SLOW INCREASE IN MAINLY UPPER LEVEL MOISTURE.
THEREFORE EXPECT BETTER CHC OF CONVECTION ON SUNDAY BUT
GFS AND ECMWF BOTH SHOWING A WEAKENED ERIKA REACHING OVER SOUTHEAST
FLORIDA COAST SUN NIGHT INTO MON WITH EASTERLY FETCH OF MOISTURE
REACHING AS FAR NORTH AS SOUTH CAROLINA. OVERALL WESTWARD
ADJUSTMENT BY NHC AND GUIDANCE IS EVEN FARTHER WEST. MUCH
UNCERTAINTY STILL EXISTS WITH TRACK AND INTENSITY AND THEREFORE
WILL NEED TO ADJUST IN FUTURE FORECASTS.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 330 AM FRIDAY...TRENDING DRIER IN OVERALL FORECAST AS LATEST
MODEL RUNS SHOW ERIKA OVER FLORIDA ON MONDAY AND THEN TAKING A
TURN IN GEORGIA OR POSSIBLY TRACKING ACROSS FLORIDA TOWARD THE
GULF COAST. THIS WOULD PRODUCE A GREATER EXTENDED EAST TO
NORTHEASTERLY FETCH OVER THE CAROLINAS. FOR NOW KEPT WITH LOWER
END CHC POPS AND WITH GREATEST IMPACTS FROM ERIKA STILL EXPECTED
MID WEEK...WED INTO THURS. IF ERIKA DOES TAKE A TRACK TO OUR SOUTH
MAY END UP WITH MORE IN THE WAY OF SOME GUSTY ON SHORE WINDS AND
EXTENDED SWELL ENERGY PRODUCING SOME COASTAL IMPACTS BUT WITH SUCH
UNCERTAINTY IN THE MODELS IT IS STILL DIFFICULT TO SAY WITH ANY
CERTAINTY. LATEST GFS KEEPS PCP WATER VALUES LOWER THAN 1.5 INCHES
THROUGH MOST OF PERIOD OVER NC WITH VALUES REACHING UP CLOSE TO 2
INCHES ON NORTHERN STRETCH OF ERIKA INTO SOUTH CAROLINA. UPPER
RIDGE BUILDING OVER THE EASTERN CONUS WILL LEAVE A WEAKNESS BUT
TRACK WILL ALSO BE DEPENDENT ON STRENGTH OF ERIKA AS SHE MAKES HER
WEST NORTHWEST. THE GFS WANTS TO PULL ERIKA TOWARD THE WEST
GETTING PULLED BY THE MID TO UPPER LOW OVER THE WESTERN GULF.
OVERALL WENT A BIT MORE OPTIMISTIC FOR OUR AREA WITH A BIT LESS
CLOUD COVER AND LESS WIDESPREAD CONVECTION. RAISED MAX TEMPS A
BIT...EXPECTING MID TO UPPER 80S MOST PLACES WITH LOWS IN THE LOW
TO MID 70S.
&&
.AVIATION /18Z FRIDAY THROUGH TUESDAY/...
AS OF 18Z...A FRONTAL SYSTEM IS LOCATED JUST OFF THE COAST THIS
AFTERNOON WITH ISOLATED SHOWERS ALONG IT. AN AREA OF HIGH PRESSURE
IS TO THE N OF THE TERMINALS AND IS SHOWING SIGNS OF BUILDING SOUTH.
WINDS WILL BE NE-ENE THIS AFTERNOON AT 10-15 KTS AT ALL TERMINALS.
TEMPO MVFR CIGS WILL BE POSSIBLE EARLY THIS AFTERNOON AT THE COASTAL
TERMINALS...BUT GENERALLY SCT/BKN LOW VFR CIGS EXPECTED THROUGH
MIDNIGHT Z. SCT SKIES EXPECTED AT KFLO/KLBT.
WINDS DECREASE THIS EVENING TO NE AT 5 KT OR LESS. GUIDANCE IS
SUGGESTING FOG DEVELOPMENT OVERNIGHT WITH BEST CHANCE AT KLBT WHERE
WINDS ARE LIGHTEST. SINCE DEWPOINTS ARE RELATIVELY LOW AND GROUND
TEMPS WARM THINK CHANCES ARE LOW ATTM. VFR AFTER SUNRISE WITH NE
WINDS.
EXTENDED OUTLOOK...PREDOMINATELY VFR WITH ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS THROUGH THE EXTENDED. BRIEF MORNING
FOG/STRATUS IS ALSO EXPECTED EACH DAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/... AS OF 1015 AM FRIDAY...MODERATE NE
SURGE OF DRY AIR CONTINUES...POSSIBLY STEADY STATE FOR THE NEXT
HANDFUL OF HOURS BUT STARTING TO ABATE AROUND MIDDAY. THIS HAS
GOTTEN WAVE FACES RATHER STEEP BUT NOT QUITE SCEC-WORTHY IN HEIGHT.
THERE ARE NO CHANGES TO THE FORECAST AT THIS TIME. PREVIOUS
DISCUSSION FOLLOWS:
AS OF 650 AM FRIDAY...THE ENTIRE ILM COASTAL WATERS SHOULD NOW BE
ENCOMPASSED WITH A STEADY AND MODEST NE WIND. THE SFC PG FROM THE
RIDGING FROM THE 1020+ HIGH FROM THE NORTH WILL BE TIGHT ENOUGH TO
PRODUCE A SOLID 15 KT SUSTAINED WIND...EXCEPT INITIALLY 15 TO 20
KT ACROSS THE ILM NC WATERS. LOOKING AT KLTX VWP AND ADJACENT 88D
VWPS...WINDS 1K TO 2K FT OFF THE DECK ARE RUNNING NE-ENE AT 15 TO
30 KT. WITH SOME OF THIS MIXING DOWN TO THE OCEAN SFC AS 20+ WIND
GUSTS. LOOK FOR A SOLID 15 KT NE WIND SPEED TONIGHT FOR ALL
WATERS...WIND DIRECTIONS MAY BRIEFLY VEER TO THE ENE-E NEAR SHORE
THIS AFTN/EARLY EVENING DUE TO A RESULTANT WIND BOUNDARY.
SIGNIFICANT SEAS WILL RUN A SOLID 4 FT FOR THE ILM NC WATERS FROM
CAPE FEAR NORTHWARD THRU THE PERIOD...AND 2 TO 4 FT SOUTH OF THE
CAPE. THE 4 TO 6 SECOND PERIOD WIND WAVES WILL DOMINATE THE
SIGNIFICANT SEAS...WITH THE UNDERLYING 1 TO 1.5 FOOT ESE GROUND
SWELL AT 11-12 SECOND PERIODS REMAINING VISUALLY PRESENT. THE
SCATTERED CONVECTION COVERAGE ASSOCIATED WITH THE SOMEWHAT STALLED
SFC FRONT...WILL SWITCH TO THE ADJACENT OFFSHORE WATERS.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 330 AM FRIDAY...NORTHEAST WINDS ON SATURDAY BETWEEN HIGH
PRESSURE EXTENDING DOWN OVER THE CAROLINAS AND WEAK LOW PRESSURE
DEVELOPING ALONG LINGERING BOUNDARY OFF SHORE. AS THIS LOW PULLS
AWAY THROUGH SUNDAY...WINDS MAY COME AROUND TO A MORE EASTERLY ON
SHORE DIRECTION AROUND HIGH PRESSURE. EXPECT DEEPEST MOISTURE AND
CONVECTION MAINLY EAST OF WATERS ASSOCIATED WITH LINGERING
BOUNDARY AND WAVE OF LOW PRESSURE ALONG IT. LATEST FORECAST TRACKS
WEAKENED ERIKA OVER FLORIDA BY SUNDAY NIGHT INTO EARLY MONDAY.
THIS WOULD MAINLY PRODUCE EASTERLY SWELL ENERGY REACHING INTO THE
LOCAL WATERS OVER THE WEEKEND WITH SEAS BASICALLY REMAINING 2 TO 4
FT MOST WATERS.
LONG TERM /MONDAY THROUGH TUESDAY/...
AS OF 330 AM FRIDAY...LATEST FORECAST TRACKS ERIKA OVER FLORIDA
AND KEEPS TRENDING WESTWARD WITH TIME GETTING PULLED BY MID TO
UPPER LOW IN THE WESTERN GULF. MAY SEE WINDS REMAIN E-NE ONLY
RISING UP TO 15 KTS. WITH SO MUCH UNCERTAINTY IN MODEL RUNS...WILL
NEED TO KEEP AN EYE ON EVOLUTION OF ERIKA. FOR NOW WILL KEEP
MAINLY EAST WINDS LESS THAN 15 KTS AND SEAS BASICALLY 2 TO 4 FT
WITH A DIMINISHING LONGER PERIOD SWELL.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...RGZ
NEAR TERM...MBB/DCH
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...MRR
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
311 PM CDT FRI AUG 28 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 304 PM CDT FRI AUG 28 2015
WATER VAPOR SHOWS THE MAIN SHORT WAVE OVER NW ONTARIO MOVING
TOWARD LAKE SUPERIOR. UPSTREAM IN SOUTHERN MANITOBA ARE SOME OTHER
WEAKER SHORT WAVES. A FEW OTHER WEAKER SHORT WAVES ALSO INTO SOUTH
CENTRAL NORTH DAKOTA. SO PATTERN IS PRETTY MUDDLED ALOFT. AT THE
SFC NOT MUCH BETTER. SHORT RANGE MODELS KEEP INDICATING A SFC
TROUGH ADVANCING INTO THE NRN RRV THIS AFTN AND THEN SINKING SOUTH
THIS LATE AFTN/EVE. SO FAR REAL HARD TO PICK ONE OUT. WINDS ARE
SOUTH-SOUTHWEST TO 25 KTS GRAND FORKS-GRAFTON AND DO SHIFT A TAD
MORE WEST LANGDON-DEVILS LAKE REGION AND THEN IN SOUTHERN MANITOBA
PRETTY LIGHT AND VARIABLE. SO AT THIS POINT HARD TO TELL IF INDEED
A WIND SHIFT LINE WILL ADVANCE SOUTH AS HRRR/RAP/NAM AND NCEP
MODELS SAY. PRETTY UNSTABLE IN NRN ERN ND/NW MN WITH MAX MU CAPES
IN THE 4000 J/KG RANGE NR ROSEAU-HALLOCK...LIKELY IMPACTED BY
HIGHER DEW PTS NOTED BY AWOS`S. THAT SAID CONVECTIVE MODELS
CONTINUE TO INDICATE SOME DEVELOPMENT ALONG A WEAK BOUNDARY
JAMESTOWN-FARGO-BEMIDJI-PARK RAPIDS AREA 00Z-03Z PERIOD. ALSO
DEVELOPMENT WILL CONTINUE OVER LAKE OF THE WOODS. MORE UNCERTAIN
IN THE NRN VALLEY AND FAR NW MN WHERE INSTABILITY MAX IS AS
CONVECTIVE SHORT RANGE MODELS SHOW NOTHING TO DEVELOP BUT OBS MAY
INDICATE ATMOSPHERE PRIMED. SO WILL CONTINUE TO WATCH AND HAVE
POPS IN AREAS AS SHORT RANGE MODELS INDICATE BUT ALBEIT A BIT
WIDER AREA. INTO SATURDAY THE HEAT AND HUMIDITY IS ON AS UPPER
RIDGE BUILDS IN.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 304 PM CDT FRI AUG 28 2015
HOT AND HUMID AND A BIT BREEZY ON SUNDAY. NEXT FRONT DUE TO MOVE
THRU LATE SUN NIGHT INTO MONDAY WITH A RISK OF A FEW
SHOWERS/STORMS.
FOR MONDAY NIGHT THROUGH FRIDAY...
THE TREND FOR THIS PERIOD IS GENERALLY WARM AND UNSETTLED. THE
PERIOD STARTS OFF WITH SOUTHWEST FLOW ALOFT OVER THE REGION AND A
WEAK SHORT WAVE MOVING THROUGH THE AREA MONDAY NIGHT. WEAK WAVES
WILL CONTINUE TO AFFECT THE AREA THROUGH MUCH OF THE WEEK...WITH A
WARM/HOT AIR MASS IN PLACE AND OCCASIONAL THUNDERSTORM CHANCES.
MID 80S TO LOW 90S WILL BE COMMON...WITH SOME MID 90S POSSIBLE AS
WELL. TOWARD THE END OF THE WEEK...AN UPPER LEVEL TROUGH/LOW WILL
DEEPEN OVER THE WESTERN STATES...WITH A SURFACE LOW LIKELY
DEVELOPING IN THE NORTHERN PLAINS. THE GFS AND ECMWF DIFFER ON
DETAILS...INCLUDING THE LOCATION OF THE COOLER AIR...BUT BOTH HAVE
A SFC LOW IN THE GENERAL REGION.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 102 PM CDT FRI AUG 28 2015
MODELS ARE STILL HINTING AT THUNDERSTORM DEVELOPMENT POTENTIALLY
THIS AFTERNOON. NAM AND SREF STILL POINT TOWARD ACTIVITY NEAR
TVF/GFK BY MID AFTERNOON. HOWEVER...THE LATEST HRRR KEEPS ACTIVITY
FURTHER EAST AND SOUTH...MORE IN THE KBJI TO KFAR AREAS AROUND 00Z.
REGARDING TS...HAVE MADE ONLY MINOR CHANGES COMPARED TO PREVIOUS
FORECAST. NAM AND SREF ARE SHOWING SIGNS OF BR DEVELOPMENT LATE
TONIGHT. HAVE KEPT IT AT 5SM AROUND SUNRISE AT GFK/BJI/TVF.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...RIDDLE
LONG TERM...KNUTSVIG/RIDDLE
AVIATION...KNUTSVIG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
107 PM CDT FRI AUG 28 2015
.UPDATE...
ISSUED AT 102 PM CDT FRI AUG 28 2015
BIGGEST QUESTION IS WHERE/IF T-STORMS WILL RE-DEVELOP. SFC OBS
SHOW A SOUTH-SOUTHWEST WIND TO 25 KTS IN THE NRN VALLEY WITH TEMPS
NR 80 AND DEW PTS 65-70 IN MUCH OF THE RRV AND E ND AND FAR NW MN.
A WEAK WIND SHIFT IS NOTED BUT MORE IN CNTRL ND ROLLA-CANDO AREA
AND INTO SW MANITOBA. CONVECTIVE SHORT RANGE MODELS INDICATE A
WEAK WIND SHIFT DROPPING SOUTH THIS AFTN AND SOME STORMS FIRING
FARGO-DETROIT LAKES AREA 00Z OR SO. THAT HAS BEEN A CONSISTENT
SIGNAL BUT YET TROUGH/WIND SHIFT LINE AS DEPICTED BY HRRR STILL AM
NOT SURE WILL OCCUR. TRENDED POPS THE WAY OF THE HRRR AND HOP WRF
MODELS WHICH SO THE FARGO-DTL CONVECTION.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 355 AM CDT FRI AUG 28 2015
VISIBILITY ACROSS NORTHWEST MINNESOTA WILL CONTINUE TO BE VARIABLE
IN PATCHY FOG THROUGH THE PREDAWN HOURS... THOUGH ANY FOG SHOULD
DISSIPATE SHORTLY AFTER SUNRISE.
A STRONG THUNDERSTORM COMPLEX IN SOUTHERN MANITOBA THIS HOUR IS
EXPECTED TO DIMINISH IN INTENSITY AS IT BRUSHES THE U.S. BORDER
ACROSS NORTHERN CAVALIER AND KITTSON COUNTIES AROUND 12Z. ISOLATED
SHOWER AND THUNDERSTORM ACTIVITY IS THEN POSSIBLE THROUGH THE
FORENOON THROUGHOUT THE NORTH BORDER COUNTIES... SPREADING ACROSS
FAR NORTHCENTRAL MINNESOTA THROUGH THE EARLY AFTERNOON.
A SECOND ROUND OF SCATTERED SHOWERS AND THUNDERSTORMS ARE
POSSIBLE...STARTING IN EAST CENTRAL ND FROM MID AFTERNOON AND
SPREADING EASTWARD ALONG AN EAST-WEST ORIENTED TROF AXIS INTO
NORTHWEST MINNESOTA INTO THE EARLY EVENING. EXTENT AND SEVERITY
OF THESE STORMS WILL DEPEND ON AFTERNOON HEATING... WITH AFTERNOON
TEMPERATURES REACHING INTO THE MID 80S IN SPOTS... THUS SOME
STORMS COULD PRODUCE SMALL HAIL AND GUSTY WINDS.
LATER TONIGHT AND SATURDAY WILL SEE A RETURN TO LIGHT SOUTHERLY
FLOW AND A DRIER...MORE STABLE H5 RIDGE BUILDING IN ALOFT.
TEMPERATURES OVERALL WILL BE A BIT WARMER THAN SEASONAL NORMALS.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 355 AM CDT FRI AUG 28 2015
SATURDAY NIGHT AND SUUNDAY...EXPECT MORE OF THE SAME. WITH A WARM
H5 RIDGE ALOFT AND LIGHT SOUTHERLY WINDS AT THE SURFACE...EXPECT
SEASONABLY WARM AND DRY CONDITIONS WITH HIGH TEMPERATURES RANGING
FRM THEMID 80S IN CENTRAL MINNESOTA LAKES COUNTRY TO THE LOWER 90S
IN THE DEVILS LAKE BASIN.
MONDAY-THURSDAY...A VERY SUMMER-LIKE WEATHER PATTERN WILL CONTINUE
HEADING INTO THE START OF SEPTEMBER. THE UPPER RIDGE WILL FLATTEN
EARLY ON WITH SHORTWAVE ENERGY PASSING NORTH ACROSS CANADA. AN
ASSOCIATED WEAK SFC BOUNDARY COULD FIRE A FEW STORMS OFF ON
MONDAY...ALTHOUGH THE BEST UPPER SUPPORT WILL BE WELL NORTH OVER
CANADA. THIS BOUNDARY SHOULD THEN WASH OUT WITHIN PERSISTENT
SOUTHWESTERLY FLOW ALOFT. NOT VERY OPTIMISTIC ABOUT PRECIP CHANCES
LATER IN THE PERIOD...ALTHOUGH A STORM COULD NOT BE RULED OUT GIVEN
THE SOUTHWEST FLOW PATTERN/RATHER MOIST ENVIRONMENT. WARMER MID-
LEVEL TEMPS MAY ACT TO SUPPRESS CONVECTION BY WED INTO THUR AS THE
PATTERN AMPLIFIES AHEAD OF AN APPROACHING FRONT. DETAILS OUT AT THIS
RANGE ARE STILL QUITE UNCERTAIN THOUGH.
AVE HIGHS/LOWS FALL INTO THE MID TO UPPER 70S/LOW 50S DURING EARLY
SEPT...BUT HIGHS SHOULD SHOULD REACH THE 80S WITH LOWS MAINLY IN THE
60S THROUGH THUR. WED AND POSSIBLY THUR LOOK TO BE WARMEST AS 850 MB
TEMPS RISE TO NEAR 25C. SO SOME HIGHS AT OR ABOVE 90 ARE POSSIBLE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 102 PM CDT FRI AUG 28 2015
MODELS ARE STILL HINTING AT THUNDERSTORM DEVELOPMENT POTENTIALLY
THIS AFTERNOON. NAM AND SREF STILL POINT TOWARD ACTIVITY NEAR
TVF/GFK BY MID AFTERNOON. HOWEVER...THE LATEST HRRR KEEPS ACTIVITY
FURTHER EAST AND SOUTH...MORE IN THE KBJI TO KFAR AREAS AROUND 00Z.
REGARDING TS...HAVE MADE ONLY MINOR CHANGES COMPARED TO PREVIOUS
FORECAST. NAM AND SREF ARE SHOWING SIGNS OF BR DEVELOPMENT LATE
TONIGHT. HAVE KEPT IT AT 5SM AROUND SUNRISE AT GFK/BJI/TVF.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...RIDDLE
SHORT TERM...GUST
LONG TERM...GUST/MAKOWSKI
AVIATION...KNUTSVIG
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
215 PM EDT FRI AUG 28 2015
.SYNOPSIS...
WARMING TREND INTO WEEKEND. ISOLATED SHOWER POSSIBLE IN
MOUNTAINS. MORE HUMID SUNDAY INTO NEXT WEEK...WITH A BETTER
CHANCE OF SHOWERS...ESPECIALLY MONDAY INTO TUESDAY.
&&
.NEAR TERM /THROUGH SATURDAY/...
ANOTHER QUIET WEATHER DAY WITH CU FORMING OVER THE HIGHER
TERRAIN...AND ALSO IN SE OHIO. NAM CONTINUES TO SHOW SHOWERS
DEVELOPING OVER THE MOUNTAINS TODAY. DID LEAVE AN ISOLATED SHOWER
IN...BUT THINK THE HRRR HAS A BETTER SOLUTION KEEPING SHOWERS EAST
OF CWA WHERE BETTER DEVELOPED CU ARE SHOWING ON SATELLITE.
HIGH PRESSURE DRIFTS NORTHEAST TONIGHT...AND MODELS TRYING TO
SHOW SOME CLOUDS MOVING IN ACROSS THE SOUTH LATE TONIGHT AND
DRIFTING NORTH THROUGH THE DAY. ANTICIPATE VALLEY FOG BEGINNING TO
FORM...BUT MAY BE TEMPERED BY CLOUDS...ESPECIALLY ACROSS THE
SOUTH.
WITH A BIT MORE MOISTURE COMING IN SATURDAY...THINK UPSLOPE FLOW
SHOULD LEAD TO AN ISOLATED SHOWER OR TSTORM ACROSS THE MOUNTAINS.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
THE TRANSITION FROM WEAK UPPER RIDGING TO WEAK UPPER TROUGHING
OVER THE EASTERN U.S...WHICH WILL ALLOW AN UPPER DISTURBANCE TO
EJECT NORTHEASTWARD OUT OF THE NORTHERN GULF OF MEXICO...LOOKS TO
BE DELAYED BY ABOUT 24 HOURS. THUS...SUNDAY AFTERNOON CONVECTION
LOOKS TO BE MAINLY WIDELY SCATTERED AND OVER THE MOUNTAINS.
LOOK FOR TEMPERATURES IN THE UPPER 80S WITH MORE HUMID
CONDITIONS SUNDAY.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
WITH VERY WARM AND MOIST AIR IN PLACE...THE AFOREMENTIONED UPPER
DISTURBANCE LIFTING NORTHEAST ACROSS THE AREA MONDAY INTO
TUESDAY WILL BRING A BETTER CHANCE OF SHOWERS AND A STORM...ESPECIALLY
OVER THE MOUNTAINS. UPPER RIDGING WILL AGAIN BUILD OVER THE AREA
FOR THE MIDDLE AND LATER PART OF NEXT WEEK...WITH VERY WARM AND
HUMID CONDITIONS PREVAILING...BUT LITTLE RAINFALL. TEMPERATURES
WILL GENERALLY BE NEAR 90 DEGREES EACH DAY.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
VFR EXPECTED TODAY WITH A 3-4KFT CU DECK AND LIGHT FLOW. RIVER
VALLEY FOG EXPECTED AGAIN TONIGHT...HOWEVER SOME UNCERTAINTY ON
JUST HOW DENSE IT WILL BECOME ACROSS THE SOUTH AS CLOUDS INCREASE
DURING THE PRE-DAWN HOURS. HAVE MVFR FOG DEVELOPING HTS-CRW THEN
DISSIPATING SHORTLY BEFORE SUNRISE. WHILE FARTHER NORTH HAVE IFR
RIVER VALLEY FOG...WITH CLOUDS FILLING IN AFTER SUNRISE.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SATURDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING/INTENSITY OF DENSE RIVER VALLEY FOG COULD
VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H M M
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 18Z SATURDAY...
SPOTTY IFR IN RIVER VALLEY FOG POSSIBLE LATE SATURDAY INTO EARLY
SUNDAY DEPENDING ON CLOUDS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JMV/MZ
NEAR TERM...MZ
SHORT TERM...JMV
LONG TERM...JMV
AVIATION...MZ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
133 PM EDT FRI AUG 28 2015
.SYNOPSIS...
WARMING TREND INTO WEEKEND. ISOLATED SHOWER POSSIBLE IN
MOUNTAINS. MORE HUMID SUNDAY INTO EARLY NEXT WEEK...WITH BETTER
CHANCE OF SHOWERS...ESPECIALLY LATER SUNDAY INTO SUNDAY NIGHT.
&&
.NEAR TERM /THROUGH SATURDAY/...
ANOTHER QUIET WEATHER DAY WITH CU FORMING OVER THE HIGHER
TERRAIN...AND ALSO IN SE OHIO. NAM CONTINUES TO SHOW SHOWERS
DEVELOPING OVER THE MOUNTAINS TODAY. DID LEAVE AN ISOLATED SHOWER
IN...BUT THINK THE HRRR HAS A BETTER SOLUTION KEEPING SHOWERS EAST
OF CWA WHERE BETTER DEVELOPED CU ARE SHOWING ON SATELLITE.
HIGH PRESSURE DRIFTS NORTHEAST TONIGHT...AND MODELS TRYING TO
SHOW SOME CLOUDS MOVING IN ACROSS THE SOUTH LATE TONIGHT AND
DRIFTING NORTH THROUGH THE DAY. ANTICIPATE VALLEY FOG BEGINNING TO
FORM...BUT MAY BE TEMPERED BY CLOUDS...ESPECIALLY ACROSS THE
SOUTH.
WITH A BIT MORE MOISTURE COMING IN SATURDAY...THINK UPSLOPE FLOW
SHOULD LEAD TO AN ISOLATED SHOWER OR TSTORM ACROSS THE MOUNTAINS.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
HIGH PRESSURE AT THE SFC AND ALOFT WILL CONTINUE TO PRODUCE
SUBSIDENCE WITH DRY AIR AND FAIR WEATHER CONDITIONS. THE SFC HIGH
PRESSURE WILL MOVE EAST ALLOWING SOUTH TO SOUTHWEST FLOW INTO THE
AREA...TO INCREASE TEMPERATURES AND HUMIDITY THROUGH THE WEEKEND.
THIS SCENARIO COULD PRODUCE CONVECTION ALONG THE ELEVATED HEAT
SOURCES IN THE MOUNTAINS.
WENT CLOSER TO THE SUPER BLEND GUIDANCE FOR TEMPERATURES THROUGH
THE PERIOD. GENERALLY...EXPECT THE HOTTEST DAY ON SATURDAY WITH
TEMPERATURES REACHING THE UPPER 80S LOWLANDS RANGING INTO THE MID
70S HIGHEST ELEVATIONS.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
THE MAIN CHANGE TO THIS PERIOD WILL BE A STRONGER UPPER
DISTURBANCE FROM THE LOWER MISSISSIPPI VALLEY LIFTING NORTHEAST
ACROSS THE AREA SUNDAY AND SUNDAY NIGHT...ENHANCING THE POTENTIAL
FOR SHOWERS AREA WIDE IN THE VERY WARM AND HUMID AIRMASS IN PLACE.
THIS PERIOD STILL SHOWS A BERMUDA HIGH OVER THE WESTERN ATLANTIC
EXPANDING WESTWARD. THIS EVOLVES INTO A WELL DEFINED UPPER RIDGE
HOLDING OVER THE WESTERN U.S. AND A BUILDING UPPER RIDGE OVER THE
WESTERN ATLANTIC...LEAVING A WEAK UPPER TROUGH BETWEEN THESE UPPER
RIDGES OVER THE EASTERN U.S.. WITH THE SURFACE HIGH CENTER ALSO
BUILDING OFF THE SOUTHEAST COAST...MOISTURE AND HEAT WILL CONTINUE
TO INCREASE ON A SOUTHERLY FLOW REGIME THIS WEEKEND INTO EARLY
NEXT WEEK. THIS WILL GIVE RISE TO A CHANCE OF MAINLY A DIURNAL
SHOWER OR THUNDERSTORM...ESPECIALLY IN THE MOUNTAINS...AND
ESPECIALLY SUNDAY AS A VERY WEAK UPPER DISTURBANCE LIFTS NORTHEAST
FROM THE GULF STATES. TEMPERATURES WILL GENERALLY APPROACH 90
DEGREES EACH DAY WITH RATHER HUMID CONDITIONS.
&&
.AVIATION /17Z FRIDAY THROUGH TUESDAY/...
VFR EXPECTED TODAY WITH A 3-4KFT CU DECK AND LIGHT FLOW. RIVER
VALLEY FOG EXPECTED AGAIN TONIGHT...HOWEVER SOME UNCERTAINTY ON
JUST HOW DENSE IT WILL BECOME ACROSS THE SOUTH AS CLOUDS INCREASE
DURING THE PRE-DAWN HOURS. HAVE MVFR FOG DEVELOPING HTS-CRW THEN
DISSIPATING SHORTLY BEFORE SUNRISE. WHILE FARTHER NORTH HAVE IFR
RIVER VALLEY FOG...WITH CLOUDS FILLING IN AFTER SUNRISE.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SATURDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING/INTENSITY OF DENSE RIVER VALLEY FOG COULD
VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 15 16 17 18 19 20 21 22 23 00 01 02
EDT 1HRLY 11 12 13 14 15 16 17 18 19 20 21 22
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY M M H H H H H H H M M M
EKN CONSISTENCY M H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 18Z SATURDAY...
SPOTTY IFR IN RIVER VALLEY FOG POSSIBLE LATE SATURDAY INTO EARLY
SUNDAY DEPENDING ON CLOUDS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JMV/MZ
NEAR TERM...MZ
SHORT TERM...ARJ
LONG TERM...JMV
AVIATION...MZ
AREA FORECAST DISCUSSION
NWS NORMAN OK
309 PM CDT FRI AUG 28 2015
.DISCUSSION...
DETERMINING RAIN CHANCES TONIGHT IS THE PRIMARY FORECAST CHALLENGE
OF THE DAY.
OVERALL...SLIGHTLY LOWERED RAIN CHANCES THROUGH TONIGHT DUE TO
WEAK FORCING FOR PRODUCING RAINFALL. DID NOT GO ABOVE 20 PERCENT
IN ANY GIVEN LOCATION.
THROUGH MIDNIGHT TONIGHT...THINK A FEW LIGHT SHOWERS AND
SPRINKLES WILL CONTINUE WHERE THERE IS SOME MID LEVEL MOISTURE
CONVERGENCE...GENERALLY NEAR AN ALTUS TO NORMAN TO CHANDLER LINE.
A FEW THUNDERSTORMS ARE POSSIBLE AS WELL MAINLY NEAR AN HIGHER
INSTABILITY AXIS EXISTS FROM HOLLIS TO CLINTON TO CHEROKEE. ANY
STORM IS EXPECTED TO BE SUBSEVERE WITH PERHAPS A FEW STRONG WIND
GUSTS UP TO 50 MPH AND SOME LOCALIZED DOWNPOURS. PRECIPITATION
COVERAGE MAY DIMINISH AFTER SUNSET DUE TO THE LOSS OF DAYTIME
HEATING. RAINFALL SHOULD RAIN SPARSE AND UNDER 0.10 INCH IN MOST
LOCATIONS.
AFTER MIDNIGHT TONIGHT...A FEW SHOWERS AND PERHAPS A FEW
THUNDERSTORMS MAY CONTINUE ACROSS THE AREA...MAINLY SOUTH OF A ELK
CITY TO PONCA CITY LINE. LATEST RUC13 SUGGESTED THAT THE 850 MB
JET MAY INCREASE OVER WESTERN NORTH TEXAS AND SOUTHERN OKLAHOMA
WHICH MAY ALLOW FOR INCREASED COVERAGE OF RAIN. HOWEVER...
INSTABILITY MAY BE LACKING. THUS...KEPT 20 PERCENT CHANCES IN
THESE AREAS.
SATURDAY...OVERALL...PARTLY TO MOSTLY SUNNY AND DRY WEATHER CAN BE
EXPECTED. WOULD NOT BE COMPLETELY SURPRISED IF A STRAY SHOWER OR STORM
OCCURRED SOUTH OF A QUANAH TEXAS TO OKLAHOMA CITY TO CHANDLER
LINE...BUT DID NOT MENTION DUE TO LOW CONFIDENCE OF OCCURRENCE.
HIGHS WILL BE NEAR TO SLIGHTLY ABOVE AVERAGE...MAINLY IN THE 90S.
SATURDAY NIGHT THROUGH FRIDAY...A DRY WEATHER PATTERN IS FORECAST
WITH NEAR OR ABOVE AVERAGE TEMPERATURES. THERE ARE SOME MODEL
DIFFERENCES MAINLY IN REGARDS TO THE LOCATION AND PROGRESSION A
MID/UPPER TROUGH SOMEWHERE OVER THE SOUTHERN PLAINS OR
SOUTHEASTERN U.S. AT THIS TIME...THINK THE DEEPEST MOISTURE AND
HIGHER RAIN CHANCES WILL STAY EAST OF OKLAHOMA AND NORTH
TEXAS...BUT CONFIDENCE IS RATHER LOW.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 68 92 67 92 / 20 10 0 0
HOBART OK 68 96 66 96 / 20 10 10 0
WICHITA FALLS TX 74 98 68 98 / 20 10 10 10
GAGE OK 63 92 60 93 / 10 0 0 0
PONCA CITY OK 67 89 64 91 / 20 10 10 0
DURANT OK 72 94 70 95 / 20 20 10 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
25/17
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1227 PM CDT FRI AUG 28 2015
.AVIATION...
SCATTERED THUNDERSTORMS WILL BE POSSIBLE AT ALL TAF SITES THIS
AFTERNOON AND EARLY EVENING BUT CONFIDENCE IN COVERAGE IS TOO LOW
TO MENTION IN THE TAF AT THE MOMENT. THESE STORMS WILL RESULT FROM
A COLD FRONT TO MOVE THROUGH THIS EVENING. ALTHOUGH WINDS WILL
SHIFT TO THE NORTH...SPEEDS ARE EXPECTED TO REMAIN LIGHT.
&&
PREV DISCUSSION... /ISSUED 331 AM CDT FRI AUG 28 2015/
SHORT TERM...
UA RIDGE CENTERED TO OUR WEST HAS FLATTENED OUT A BIT THUS RESULTING
IN WNW FLOW ALOFT PREVAILING ACROSS THE SOUTHERN PLAINS. THIS DE-
AMPLIFICATION OF THE UA RIDGE IS DUE TO AN UA SHORTWAVE THAT HAS
TRACKED ENE FROM THE ROCKIES TO ACROSS THE CENTRAL/NORTHERN PLAINS
EARLY THIS MORNING. ITS ASSOCIATED COLD FRONT HAS BEEN SAGGING SWRD
ACROSS THE TX PANHANDLE AND HAS MOVED SOUTH OF KAMA AS OF 08Z.
ALTHOUGH THE BEST LARGE SCALE ASCENT IS WELL NORTH OF THE REGION...
SCATTERED CONVECTION HAS MANAGED TO DEVELOP IN THE WAKE OF THE
FRONT ACROSS THE TX PANHANDLE...COURTESY OF ADEQUATE FRONTOGENETICAL
FORCING. NOT ONLY ARE MODEL SOLUTIONS HAVING DIFFICULTY IN SHOWING
CONSENSUS WRT TO THE TIMING OF THE FRONT /IMPINGING ON THE NRN
ZONES ANYWHERE FROM 12-18Z/ BUT ARE ALSO HAVING DIFFICULTY IN THE
SPATIAL EXTENT OF PRECIP...THUS MAKING IT HARD TO HANG YOUR HAT ON
ANY ONE PARTICULAR SOLUTION. NONETHELESS...IF THE CURRENT SPEED OF
THE FRONT DOES NOT SLOW DOWN MUCH...IT APPEARS THAT THE FRONT WILL
MOVE ACROSS THE NRN ZONES AN HOUR OR SO BEFORE SUNRISE /AS HINTED
AT BY THE RAP SOLUTION/ AND THEREFORE PROGGED TO GET HUNG UP DURING
THE DAYTIME /ORIENTED FROM SW TO NE/...HENCE NOT QUITE CLEARING THE
LOW ROLLING PLAINS. SOLUTIONS DO EXHIBIT PRECIP ORIENTED FROM THE
SWRN ZONES TO THE NERN ZONES ALONG THE FRONT...THOUGH AS STATE
EARLIER...SOME SOLUTIONS ARE A BIT MORE BULLISH IN ITS SPATIAL
EXTENT AND QPF AMOUNTS. WILL THEREFORE HOLD ON TO BEST POPS BEING
SHOWN FROM SW TO NE...WITH LOWEST POPS ACROSS THE LOW ROLLING
PLAINS THROUGHOUT THE SHORT TERM PERIOD.
STEEPENING LAPSE RATES THIS AFTN COUPLED WITH DAYTIME DESTABILIZATION
MAY RESULT IN A FEW STORMS GENERATING BRIEF WIND GUSTS...BUT SEVERE
POTENTIAL APPEARS LOW GIVEN BEST UL SUPPORT WILL BE NORTH OF THE
REGION.
BEING THAT THE COLD FRONT IS NOT TERRIBLY STRONG /AS 850 MB TEMPS DO
NOT DROP TERRIBLY LOW/ IT WILL STILL BE A FEW DEGREES COOLER THAN
YESTERDAY WITH HIGHS RANGING FROM THE UPPER 80S ACROSS THE FAR SW TX
PANHANDLE TO THE UPPER 90S TO LOWER 100 DEGREE READINGS ACROSS THE
LOW ROLLING PLAINS. OVERNIGHT LOWS WILL BE IN THE 60S AND 70S.
LONG TERM...
A FAIRLY QUIET PERIOD COMING UP. THE LONG WAVE UPPER AIR PATTERN
OVER THE CONUS WILL REMAIN GENERALLY THE SAME THROUGH NEXT WEEK
WITH A TROUGH OVER THE WEST AND RIDGING FROM THE SRN PLAINS TO THE
NORTHEAST. HOWEVER...WEAKNESSES IN THE RIDGE WILL LEAVE HEIGHTS
AND THICKNESSES OVER THE AREA OF A MAGNITUDE THAT SHOULD KEEP
TEMPERATURES FROM GETTING TOO FAR OVER SEASONAL NORMS. ONLY OTHER
ISSUE IS POTENTIAL FOR GENERALLY AFTN AND EVENING PRECIP IN THE
NWRN COUNTIES VCNTY OF SFC TROUGH AND LOW LEVEL INSTABILITY AXIS.
MONDAY AND TUESDAY WOULD BE FAVORED. CONFIDENCE REMAINS LOW ATTM
AND HAVE KEPT MENTION OUT ATTM.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 61 89 61 91 / 20 10 0 0
TULIA 62 91 61 91 / 20 10 0 0
PLAINVIEW 63 91 63 91 / 30 10 0 0
LEVELLAND 64 91 64 92 / 30 10 10 0
LUBBOCK 65 92 65 93 / 30 10 0 0
DENVER CITY 63 91 63 92 / 30 10 0 0
BROWNFIELD 65 92 65 93 / 30 10 0 0
CHILDRESS 69 96 68 97 / 20 10 0 0
SPUR 69 94 67 96 / 20 10 10 0
ASPERMONT 72 97 70 99 / 10 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
01/99/