Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 08/16/13
AREA FORECAST DISCUSSION...UPDATED
NWS TUCSON AZ
555 AM MST WED AUG 14 2013
.SYNOPSIS...INCREASING MOISTURE WILL PROVIDE GREATER COVERAGE OF
SHOWERS AND THUNDERSTORMS STARTING TODAY AND CONTINUING INTO EARLY
NEXT WEEK. OTHERWISE...STRONG HIGH PRESSURE ALOFT WILL RESULT IN
ABOVE NORMAL DAYTIME TEMPERATURES ACROSS MUCH OF THE AREA THROUGH
THIS WEEKEND.
&&
.UPDATE...THE OFFICIAL FORECAST WAS UPDATED TO REMOVE THE PREVIOUS
DEPICTION OF ISOLATED TO SCATTERED SHOWERS/TSTMS ACROSS SOUTH
CENTRAL PINAL COUNTY THRU 8 AM MST THIS MORNING...AND TO INSERT A
SLIGHT CHANCE OF SHOWERS/TSTMS IN NEAR THE INTERNATIONAL BORDER
ADJACENT SOUTH CENTRAL PIMA COUNTY THRU THE REST OF THIS MORNING.
THE HIGHER TERRAIN EAST OF TUCSON SHOULD EXPERIENCE SHOWER/TSTM
DEVELOPMENT AROUND 18Z-19Z.
&&
.DISCUSSION...KEMX WSR-88D DETECTED ISOLATED 30-40 DBZ ECHOES OVER
SOUTH-CENTRAL COCHISE COUNTY AT 0905Z. OTHER PRECIP ECHOES WERE JUST
SOUTH OF THE INTERNATIONAL BORDER ADJACENT SWRN COCHISE/ERN SANTA
CRUZ COUNTIES. MESOSCALE CONVECTIVE SYSTEM DECAYING ACROSS NORTHERN
AND CENTRAL SONORA AT THIS TIME...WITH CLOUD TOPS GENERALLY WARMING
DURING THE PAST 2-3 HOURS. BASED ON RADAR TRENDS AS WELL AS THE
PROXIMITY OF THIS WEAKENING SYSTEM TO SE AZ...HAVE OPTED FOR
ISOLATED SHOWERS/TSTMS THIS MORNING ACROSS SWRN COCHISE COUNTY AND
MUCH OF SANTA CRUZ COUNTY. ISOLATED SHOWERS/TSTMS SHOULD ALSO
DEVELOP ACROSS THE WHITE MOUNTAINS OF NRN GREENLEE/GRAHAM COUNTIES
BY LATE MORNING AS PER SEVERAL RUC HRRR SOLUTIONS.
OTHERWISE...POPS WERE TRENDED UPWARD FOR THIS AFTERNOON AND THIS
EVENING BASED ON THE 14/00Z NAM/GFS/ECMWF SOLUTIONS. THUS...
SCATTERED SHOWERS/TSTMS ARE EXPECTED TO OCCUR THIS AFTERNOON AND
THIS EVENING FROM TUCSON EWD/SWD WITH LESSER CHANCES OF PRECIP NORTH
AND WEST OF TUCSON. FOR LATE TONIGHT...HAVE NOTED THAT THE GFS
CONTINUES THE POTENTIAL FOR AT LEAST ISOLATED SHOWERS/TSTMS ACROSS
MUCH OF THE AREA VERSUS THE NAM. FOR NOW HAVE LIMITED A SLIGHT
CHANCE OF SHOWERS/TSTMS LATE TONIGHT ACROSS COCHISE/SANTA CRUZ
COUNTIES WITH DRY CONDITIONS ELSEWHERE. HOWEVER...CONFIDENCE IS LOW
IN THIS SCENARIO.
THUR-SAT...
14/00Z GFS/ECMWF WERE SIMILAR WITH DEPICTING 594 DM HIGH TO BE
CENTERED OVER SE AZ THUR. UPPER RIDGE IS THEN PROGGED TO AMPLIFY
OVER THE SWRN CONUS/ROCKIES FRI-SAT. MOISTURE IS ALSO PROGGED TO
INCREASE ACROSS THIS FORECAST AREA. ALTHOUGH WARMER MID-LEVEL TEMPS
MAY LIMIT CONVECTIVE DEVELOPMENT SOMEWHAT...MOISTURE SHOULD STILL BE
SUFFICIENT TO JUSTIFY SCATTERED AFTERNOON AND EVENING SHOWERS/TSTMS
EAST AND SOUTH OF TUCSON. ISOLATED AFTERNOON AND EVENING SHOWERS/
TSTMS WILL PREVAIL FROM TUCSON WWD/NWWD.
SUN-TUE...
THERE CONTINUED TO BE DIFFERENCES BETWEEN THE GFS/ECMWF REGARDING
THE UPPER LEVEL PATTERN OVER THE WRN CONUS THIS PERIOD. THE ECMWF
DEPICTED THE UPPER HIGH TO FLATTEN SUN AS A SHORTWAVE TROUGH MOVES
NORTH OF THE AREA. UPPER HIGH IS THEN PROGGED TO AMPLIFY OVER THE
AREA MON-TUE. MEANWHILE...THE GFS MAINTAINED THE UPPER HIGH OVER
ARIZONA SUN-TUE AS THE CLOSED LOW INITIALLY NEAR THE NRN CALIFORNIA
COAST FILLS AND EJECTS NEWD INTO THE PACIFIC NW. THE UPSHOT FOR SE
AZ...MOISTURE SHOULD STILL BE SUFFICIENT FOR ISOLATED-SCATTERED
AFTERNOON AND EVENING SHOWERS/TSTMS MAINLY FROM TUCSON EWD/SWD EARLY
NEXT WEEK.
HIGH TEMPS TODAY-TUE WILL GENERALLY BE ABOUT 3-8 DEGS F ABOVE
NORMAL. THE FORECAST HIGH TEMP AT TUCSON INTERNATIONAL AIRPORT TODAY
OF 105 DEGS...IF ACHIEVED...WILL BE WITHIN ONE DEGREE OF THE RECORD
HIGH TEMP FOR THIS DATE (106 DEGS SET IN 2012...1994...AND 1988).
&&
.AVIATION...VALID THRU 15/12Z. SCT080-120 SCT-BKN300. ISOLD -SHRA
NEAR THE MEXICO BORDER THIS MORNING. THEN SCT TSRA DEVELOPING AFTER
14/17Z S AND E OF KCGZ WITH MVFR CONDITIONS AND STRONG OUTFLOW WINDS
NEAR STORMS. OTHERWISE...SURFACE WIND GENERALLY LESS THAN 10 KTS
WITH NORMAL DIURNAL DIRECTION CHANGES. AVIATION DISCUSSION NOT
UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...THUNDERSTORMS JUST SOUTH OF THE BORDER WILL HELP TO
INCREASE MOISTURE ACROSS SE AZ TODAY WITH A SLIGHT CHANCE OF SHOWERS
AND THUNDERSTORMS NEAR THE INTERNATIONAL BORDER THIS MORNING AND A
GREATER THREAT OF SHOWERS AND THUNDERSTORMS ACROSS MOST OF THE AREA
THIS AFTERNOON AND EVENING. THE INCREASE IN MOISTURE WILL ALSO BOOST
THE RH VALUES A BIT...ESPECIALLY THE OVERNIGHT RECOVERIES. FROM
THURSDAY ONWARD...UPPER LEVEL HIGH PRESSURE WILL BE OVER THE REGION
BUT THERE WILL BE ENOUGH MOISTURE TO GENERATE ISOLATED TO SCT
AFTERNOON AND EVENING CONVECTION EACH DAY. OUTSIDE OF THUNDERSTORM
WINDS...NORMAL DIURNAL WIND TRENDS ARE EXPECTED THROUGH THE
WEEKEND...WITH OCCASIONAL GUSTS DURING THE MID TO LATE AFTERNOON
HOURS DUE TO STRONG DAYTIME HEATING.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
DISCUSSION...FRANCIS
AVIATION/FIRE WEATHER...CERNIGLIA
AREA FORECAST DISCUSSION...UPDATED
NWS TUCSON AZ
410 AM MST WED AUG 14 2013
.SYNOPSIS...INCREASING MOISTURE WILL PROVIDE GREATER COVERAGE OF
SHOWERS AND THUNDERSTORMS STARTING TODAY AND CONTINUING INTO EARLY
NEXT WEEK. OTHERWISE...STRONG HIGH PRESSURE ALOFT WILL RESULT IN
ABOVE NORMAL DAYTIME TEMPERATURES ACROSS MUCH OF THE AREA THROUGH
THIS WEEKEND.
&&
.UPDATE...THE OFFICIAL FORECAST WAS UPDATED TO INCLUDED ISOLATED TO
SCATTERED SHOWERS/TSTMS ACROSS SOUTH CENTRAL PINAL COUNTY NW OF
TUCSON THRU 14/15Z (8 AM MST). 14/08Z RUC HRRR AND 14/06Z NAM
PERFORMED EXTREMELY POORLY WITH THIS ACTIVITY. THUS...UPDATE BASED
PRIMARILY ON RADAR TRENDS. OTHER PRECIP ECHOES WITH LIGHTNING
STRIKES DETECTED WERE JUST SOUTH OF THE INTERNATIONAL BORDER
ADJACENT SANTA CRUZ COUNTY.
&&
.DISCUSSION...KEMX WSR-88D DETECTED ISOLATED 30-40 DBZ ECHOES OVER
SOUTH-CENTRAL COCHISE COUNTY AT 0905Z. OTHER PRECIP ECHOES WERE JUST
SOUTH OF THE INTERNATIONAL BORDER ADJACENT SWRN COCHISE/ERN SANTA
CRUZ COUNTIES. MESOSCALE CONVECTIVE SYSTEM DECAYING ACROSS NORTHERN
AND CENTRAL SONORA AT THIS TIME...WITH CLOUD TOPS GENERALLY WARMING
DURING THE PAST 2-3 HOURS. BASED ON RADAR TRENDS AS WELL AS THE
PROXIMITY OF THIS WEAKENING SYSTEM TO SE AZ...HAVE OPTED FOR
ISOLATED SHOWERS/TSTMS THIS MORNING ACROSS SWRN COCHISE COUNTY AND
MUCH OF SANTA CRUZ COUNTY. ISOLATED SHOWERS/TSTMS SHOULD ALSO
DEVELOP ACROSS THE WHITE MOUNTAINS OF NRN GREENLEE/GRAHAM COUNTIES
BY LATE MORNING AS PER SEVERAL RUC HRRR SOLUTIONS.
OTHERWISE...POPS WERE TRENDED UPWARD FOR THIS AFTERNOON AND THIS
EVENING BASED ON THE 14/00Z NAM/GFS/ECMWF SOLUTIONS. THUS...
SCATTERED SHOWERS/TSTMS ARE EXPECTED TO OCCUR THIS AFTERNOON AND
THIS EVENING FROM TUCSON EWD/SWD WITH LESSER CHANCES OF PRECIP NORTH
AND WEST OF TUCSON. FOR LATE TONIGHT...HAVE NOTED THAT THE GFS
CONTINUES THE POTENTIAL FOR AT LEAST ISOLATED SHOWERS/TSTMS ACROSS
MUCH OF THE AREA VERSUS THE NAM. FOR NOW HAVE LIMITED A SLIGHT
CHANCE OF SHOWERS/TSTMS LATE TONIGHT ACROSS COCHISE/SANTA CRUZ
COUNTIES WITH DRY CONDITIONS ELSEWHERE. HOWEVER...CONFIDENCE IS LOW
IN THIS SCENARIO.
THUR-SAT...
14/00Z GFS/ECMWF WERE SIMILAR WITH DEPICTING 594 DM HIGH TO BE
CENTERED OVER SE AZ THUR. UPPER RIDGE IS THEN PROGGED TO AMPLIFY
OVER THE SWRN CONUS/ROCKIES FRI-SAT. MOISTURE IS ALSO PROGGED TO
INCREASE ACROSS THIS FORECAST AREA. ALTHOUGH WARMER MID-LEVEL TEMPS
MAY LIMIT CONVECTIVE DEVELOPMENT SOMEWHAT...MOISTURE SHOULD STILL BE
SUFFICIENT TO JUSTIFY SCATTERED AFTERNOON AND EVENING SHOWERS/TSTMS
EAST AND SOUTH OF TUCSON. ISOLATED AFTERNOON AND EVENING SHOWERS/
TSTMS WILL PREVAIL FROM TUCSON WWD/NWWD.
SUN-TUE...
THERE CONTINUED TO BE DIFFERENCES BETWEEN THE GFS/ECMWF REGARDING
THE UPPER LEVEL PATTERN OVER THE WRN CONUS THIS PERIOD. THE ECMWF
DEPICTED THE UPPER HIGH TO FLATTEN SUN AS A SHORTWAVE TROUGH MOVES
NORTH OF THE AREA. UPPER HIGH IS THEN PROGGED TO AMPLIFY OVER THE
AREA MON-TUE. MEANWHILE...THE GFS MAINTAINED THE UPPER HIGH OVER
ARIZONA SUN-TUE AS THE CLOSED LOW INITIALLY NEAR THE NRN CALIFORNIA
COAST FILLS AND EJECTS NEWD INTO THE PACIFIC NW. THE UPSHOT FOR SE
AZ...MOISTURE SHOULD STILL BE SUFFICIENT FOR ISOLATED-SCATTERED
AFTERNOON AND EVENING SHOWERS/TSTMS MAINLY FROM TUCSON EWD/SWD EARLY
NEXT WEEK.
HIGH TEMPS TODAY-TUE WILL GENERALLY BE ABOUT 3-8 DEGS F ABOVE
NORMAL. THE FORECAST HIGH TEMP AT TUCSON INTERNATIONAL AIRPORT TODAY
OF 105 DEGS...IF ACHIEVED...WILL BE WITHIN ONE DEGREE OF THE RECORD
HIGH TEMP FOR THIS DATE (106 DEGS SET IN 2012...1994...AND 1988).
&&
.AVIATION...VALID THRU 15/12Z. SCT080-120 SCT-BKN300. ISOLD -SHRA
NEAR THE MEXICO BORDER THIS MORNING. THEN SCT TSRA DEVELOPING AFTER
14/17Z S AND E OF KCGZ WITH MVFR CONDITIONS AND STRONG OUTFLOW WINDS
NEAR STORMS. OTHERWISE...SURFACE WIND GENERALLY LESS THAN 10 KTS
WITH NORMAL DIURNAL DIRECTION CHANGES. AVIATION DISCUSSION NOT
UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...THUNDERSTORMS JUST SOUTH OF THE BORDER WILL HELP TO
INCREASE MOISTURE ACROSS SE AZ TODAY WITH A SLIGHT CHANCE OF SHOWERS
AND THUNDERSTORMS NEAR THE INTERNATIONAL BORDER THIS MORNING AND A
GREATER THREAT OF SHOWERS AND THUNDERSTORMS ACROSS MOST OF THE AREA
THIS AFTERNOON AND EVENING. THE INCREASE IN MOISTURE WILL ALSO BOOST
THE RH VALUES A BIT...ESPECIALLY THE OVERNIGHT RECOVERIES. FROM
THURSDAY ONWARD...UPPER LEVEL HIGH PRESSURE WILL BE OVER THE REGION
BUT THERE WILL BE ENOUGH MOISTURE TO GENERATE ISOLATED TO SCT
AFTERNOON AND EVENING CONVECTION EACH DAY. OUTSIDE OF THUNDERSTORM
WINDS...NORMAL DIURNAL WIND TRENDS ARE EXPECTED THROUGH THE
WEEKEND...WITH OCCASIONAL GUSTS DURING THE MID TO LATE AFTERNOON
HOURS DUE TO STRONG DAYTIME HEATING.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
DISCUSSION...FRANCIS
AVIATION/FIRE WEATHER...CERNIGLIA
AREA FORECAST DISCUSSION
NWS TUCSON AZ
210 AM MST WED AUG 14 2013
.SYNOPSIS...INCREASING MOISTURE WILL PROVIDE GREATER COVERAGE OF
SHOWERS AND THUNDERSTORMS STARTING TODAY AND CONTINUING INTO EARLY
NEXT WEEK. OTHERWISE...STRONG HIGH PRESSURE ALOFT WILL RESULT IN
ABOVE NORMAL DAYTIME TEMPERATURES ACROSS MUCH OF THE AREA THROUGH
THIS WEEKEND.
&&
.DISCUSSION...KEMX WSR-88D DETECTED ISOLATED 30-40 DBZ ECHOES OVER
SOUTH-CENTRAL COCHISE COUNTY AT 0905Z. OTHER PRECIP ECHOES WERE JUST
SOUTH OF THE INTERNATIONAL BORDER ADJACENT SWRN COCHISE/ERN SANTA
CRUZ COUNTIES. MESOSCALE CONVECTIVE SYSTEM DECAYING ACROSS NORTHERN
AND CENTRAL SONORA AT THIS TIME...WITH CLOUD TOPS GENERALLY WARMING
DURING THE PAST 2-3 HOURS. BASED ON RADAR TRENDS AS WELL AS THE
PROXIMITY OF THIS WEAKENING SYSTEM TO SE AZ...HAVE OPTED FOR
ISOLATED SHOWERS/TSTMS THIS MORNING ACROSS SWRN COCHISE COUNTY AND
MUCH OF SANTA CRUZ COUNTY. ISOLATED SHOWERS/TSTMS SHOULD ALSO
DEVELOP ACROSS THE WHITE MOUNTAINS OF NRN GREENLEE/GRAHAM COUNTIES
BY LATE MORNING AS PER SEVERAL RUC HRRR SOLUTIONS.
OTHERWISE...POPS WERE TRENDED UPWARD FOR THIS AFTERNOON AND THIS
EVENING BASED ON THE 14/00Z NAM/GFS/ECMWF SOLUTIONS. THUS...
SCATTERED SHOWERS/TSTMS ARE EXPECTED TO OCCUR THIS AFTERNOON AND
THIS EVENING FROM TUCSON EWD/SWD WITH LESSER CHANCES OF PRECIP NORTH
AND WEST OF TUCSON. FOR LATE TONIGHT...HAVE NOTED THAT THE GFS
CONTINUES THE POTENTIAL FOR AT LEAST ISOLATED SHOWERS/TSTMS ACROSS
MUCH OF THE AREA VERSUS THE NAM. FOR NOW HAVE LIMITED A SLIGHT
CHANCE OF SHOWERS/TSTMS LATE TONIGHT ACROSS COCHISE/SANTA CRUZ
COUNTIES WITH DRY CONDITIONS ELSEWHERE. HOWEVER...CONFIDENCE IS LOW
IN THIS SCENARIO.
THUR-SAT...
14/00Z GFS/ECMWF WERE SIMILAR WITH DEPICTING 594 DM HIGH TO BE
CENTERED OVER SE AZ THUR. UPPER RIDGE IS THEN PROGGED TO AMPLIFY
OVER THE SWRN CONUS/ROCKIES FRI-SAT. MOISTURE IS ALSO PROGGED TO
INCREASE ACROSS THIS FORECAST AREA. ALTHOUGH WARMER MID-LEVEL TEMPS
MAY LIMIT CONVECTIVE DEVELOPMENT SOMEWHAT...MOISTURE SHOULD STILL BE
SUFFICIENT TO JUSTIFY SCATTERED AFTERNOON AND EVENING SHOWERS/TSTMS
EAST AND SOUTH OF TUCSON. ISOLATED AFTERNOON AND EVENING SHOWERS/
TSTMS WILL PREVAIL FROM TUCSON WWD/NWWD.
SUN-TUE...
THERE CONTINUED TO BE DIFFERENCES BETWEEN THE GFS/ECMWF REGARDING
THE UPPER LEVEL PATTERN OVER THE WRN CONUS THIS PERIOD. THE ECMWF
DEPICTED THE UPPER HIGH TO FLATTEN SUN AS A SHORTWAVE TROUGH MOVES
NORTH OF THE AREA. UPPER HIGH IS THEN PROGGED TO AMPLIFY OVER THE
AREA MON-TUE. MEANWHILE...THE GFS MAINTAINED THE UPPER HIGH OVER
ARIZONA SUN-TUE AS THE CLOSED LOW INITIALLY NEAR THE NRN CALIFORNIA
COAST FILLS AND EJECTS NEWD INTO THE PACIFIC NW. THE UPSHOT FOR SE
AZ...MOISTURE SHOULD STILL BE SUFFICIENT FOR ISOLATED-SCATTERED
AFTERNOON AND EVENING SHOWERS/TSTMS MAINLY FROM TUCSON EWD/SWD EARLY
NEXT WEEK.
HIGH TEMPS TODAY-TUE WILL GENERALLY BE ABOUT 3-8 DEGS F ABOVE
NORMAL. THE FORECAST HIGH TEMP AT TUCSON INTERNATIONAL AIRPORT TODAY
OF 105 DEGS...IF ACHIEVED...WILL BE WITHIN ONE DEGREE OF THE RECORD
HIGH TEMP FOR THIS DATE (106 DEGS SET IN 2012...1994...AND 1988).
&&
.AVIATION...VALID THRU 15/12Z. SCT080-120 SCT-BKN300. ISOLD -SHRA
NEAR THE MEXICO BORDER THIS MORNING. THEN SCT TSRA DEVELOPING AFTER
14/17Z S AND E OF KCGZ WITH MVFR CONDITIONS AND STRONG OUTFLOW WINDS
NEAR STORMS. OTHERWISE...SURFACE WIND GENERALLY LESS THAN 10 KTS
WITH NORMAL DIURNAL DIRECTION CHANGES. AVIATION DISCUSSION NOT
UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...THUNDERSTORMS JUST SOUTH OF THE BORDER WILL HELP TO
INCREASE MOISTURE ACROSS SE AZ TODAY WITH A SLIGHT CHANCE OF SHOWERS
AND THUNDERSTORMS NEAR THE INTERNATIONAL BORDER THIS MORNING AND A
GREATER THREAT OF SHOWERS AND THUNDERSTORMS ACROSS MOST OF THE AREA
THIS AFTERNOON AND EVENING. THE INCREASE IN MOISTURE WILL ALSO BOOST
THE RH VALUES A BIT...ESPECIALLY THE OVERNIGHT RECOVERIES. FROM
THURSDAY ONWARD...UPPER LEVEL HIGH PRESSURE WILL BE OVER THE REGION
BUT THERE WILL BE ENOUGH MOISTURE TO GENERATE ISOLATED TO SCT
AFTERNOON AND EVENING CONVECTION EACH DAY. OUTSIDE OF THUNDERSTORM
WINDS...NORMAL DIURNAL WIND TRENDS ARE EXPECTED THROUGH THE
WEEKEND...WITH OCCASIONAL GUSTS DURING THE MID TO LATE AFTERNOON
HOURS DUE TO STRONG DAYTIME HEATING.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
DISCUSSION...FRANCIS
AVIATION/FIRE WEATHER...CERNIGLIA
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1145 AM MDT WED AUG 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 459 AM MDT WED AUG 14 2013
...DRIER AIRMASS MAKING PROGRESS EASTWARD TODAY...POTENTIAL FOR
STRONG STORMS OUT EAST THIS AFTERNOON...
SHORTWAVE MOVING DOWN EASTERN PERIPHERY OF THE UPPER RIDGE IS
KEEPING SCATTERED THUNDERSTORMS GOING ACROSS NORTHEAST/EAST CENTRAL
CO AS LOW LEVEL JET CONTINUES TO INCREASE ACROSS THE FAR EASTERN
PLAINS. KIOWA COUNTY IS MOST LIKELY TO BE CLIPPED BY THESE LATER
THIS MORNING AND FOLLOWED THE HRRR FOR POPS IN THE SHORT TERM AS IT
APPEARS TO BE THE MODEL HANDLING CURRENT CONVECTION BEST.
THUNDERSTORMS SHOULD DIMINISH OUT EAST LATER THIS MORNING.
MEANWHILE...DRIER AIRMASS OUT WEST WILL BE ADVANCING EASTWARD TODAY
WITH SHORT RANGE HIGH RES MODELS SHOWING DEW POINTS ACROSS THE
MOUNTAINS FALLING OFF INTO THE 20S AND 30S IN THE AFTERNOON. LCLS
RISE SUBSTANTIALLY AS A RESULT...AND WITH MORE INVERTED V SOUNDINGS
EXPECT EVAPORATION BELOW CLOUD BASES TO REDUCE PCPN EFFICIENCIES OF
THUNDERSTORMS SOME. HOWEVER...ERRATIC GUSTY WINDS WILL BECOME MORE
OF A THREAT AS A RESULT. MODELS STILL SHOW ENOUGH MOISTURE AND WEAK
FORCING MOVING THROUGH THE RIDGE ASSOC WITH UPPER LEVEL JET FOR
MAINLY ISOLATED AFTERNOON THUNDERSTORMS OUT WEST...WITH SCATTERED
THUNDERSTORMS ACROSS THE SE MTS/PLAINS DURING THE AFTERNOON. BUT
GIVEN THE LOWER THREAT FOR HEAVY RAINFALL...WILL NOT HOIST A FLASH
FLOOD WATCH FOR THE BURN SCARS IN EL PASO/TELLER COUNTIES. OF
COURSE...WALDO CANYON WILL NOT BE ENTIRELY OUT OF THE WOODS AS EVEN
WITH THE DRIER AIRMASS A QUICK .50 TO .75 OF RAIN WITH A STRONGER
STORM IS STILL POSSIBLE. BUT THIS LOOKS LIKE AN OUTLIER POSSIBILITY
FOR TODAY AND MORE LIKELY TO OCCUR FARTHER EAST WHERE GRADIENT OF
HIGHER DEW POINTS WILL BE LURKING. MEANWHILE...SFC DEW POINTS WILL
BE SLOWER TO DECREASE OUT ACROSS THE EASTERN PLAINS...AND NAM12
SHOWS AN AXIS OF 1500+ J/KG OF CAPE OUT OVER THE EASTERN PLAINS
OF KIOWA...BACA...BENT...AND PROWERS COUNTIES DURING THE LATE
AFTERNOON. DEEP LAYER SHEARS WILL BE RUNNING AROUND 35-40
KTS...SUFFICIENT FOR ONE OR TWO STRONG TO SEVERE THUNDERSTORMS.
LARGE HAIL AND DAMAGING WINDS WILL BE THE PRIMARY STORM THREATS AND
SPC HAS AREA OUTLOOKED UNDER A SEE TEXT. THUNDERSTORMS SHOULD
DIMINISH AFTER MIDNIGHT WITH LACK OF FORCING AND AXIS OF LOW LEVEL
JET PULLING AWAY TO THE EAST.
OTHERWISE...TEMPERATURES SHOULD BE A LITTLE WARMER TODAY FOR ALL
AREAS...WITH WITH DRIER SFC DEW POINTS OUT WEST...STARTING TO SEE A
RETURN OF LOWS IN THE 30S FOR SOME OF THE SPOTTY VALLEY LOCATIONS
DUE TO GOOD RADIATIONAL COOLING. LOWS ACROSS THE PLAINS WILL LIKELY
STAY IN THE 50S AND 60S WITH LEE TROFFING AND AXIS OF HIGHER DEW
POINTS HELPING TO KEEP MINS UP. -KT
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 459 AM MDT WED AUG 14 2013
METEOROLOGICAL CHALLENGES DURING THE LONGER TERM INCLUDE WARMER
TEMPERATURES...POTENTIAL STRONG TO SEVERE THUNDERSTORMS OVER FAR
EASTERN SECTIONS THURSDAY AND POPS.
IT STILL APPEARS THAT DRIER AND WARMER CONDITIONS WILL DEVELOP
OVER THE MAJORITY OF THE FORECAST DISTRICT FROM THURSDAY INTO THE
WEEKEND AS UPPER RIDGING BUILDS INTO THE FOUR CORNERS REGION BY THIS
WEEKEND. ALSO...LATEST PRECIPITABLE WATER VALUE PROJECTIONS DROP
TO BETWEEN 0.50 AND 0.70 INCHES OVER THE INTERSTATE 25 CORRIDOR
DURING THIS TIME-FRAME.
STRONG TO POSSIBLY SEVERE THUNDERSTORMS MAY ALSO DEVELOP OVER
PORTIONS OF THE FAR SOUTHEASTERN COLORADO PLAINS THURSDAY AS
PROJECTED LOCALIZED CAPES AND LIS NEARING 2000 J/KG AND -7C
RESPECTIVELY INTERACT WITH 0 TO 6 KM BULK SHEARS AROUND 40 KNOTS.
WFO PUEBLO WILL CONTINUE TO MONITOR CLOSELY.
GENERALLY ISOLATED AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS
ARE STILL ANTICIPATED OVER THE MAJORITY OF THE CWFA FROM THURSDAY
INTO EARLY SUNDAY. EVEN THOUGH RATHER UNLIKELY DURING THIS
TIME-FRAME...PLEASE REMEMBER THAT IF A STRONGER STORM DIRECTLY
IMPACTS A BURN SCAR...FLASH FLOODING WOULD BE POSSIBLE.
INCREASED SHOWER AND THUNDERSTORM ACTIVITY SHOULD THEN BE
NOTED...INITIALLY OVER WESTERN SECTIONS LATER SUNDAY AND THEN
CONTINUE INTO NEXT TUESDAY AS A NORTHERLY SURFACE ATTEMPTS TO
MOVE ACROSS EASTERN SECTIONS MONDAY AND ATMOSPHERIC MOISTURE
VALUES INCREASE. FORECAST MODEL SOUNDINGS PROJECT THAT
PRECIPITABLE WATER VALUES OVER THE INTERSTATE 25 CORRIDOR
INCREASE TO AROUND ONE INCH AT TIMES BY EARLY NEXT WEEK.
AT THIS TIME...IT STILL APPEARS THAT THE HIGHEST POTENTIAL FOR
LOCALIZED HEAVY RAIN AND ASSOCIATED FLASH FLOODING
CONCERNS(ESPECIALLY OVER THE AREA BURN SCARS) WILL BE POSSIBLE BY
NEXT MONDAY AND TUESDAY. AS ALWAYS...WFO PUEBLO WILL MONITOR
CLOSELY.
ABOVE SEASONAL AVERAGE MID-AUGUST MAXIMUM TEMPERATURES SHOULD BE
EXPERIENCED OVER THE MAJORITY OF THE FORECAST DISTRICT FROM
THURSDAY INTO NEXT TUESDAY WITH THE WARMEST CONDITIONS ANTICIPATED
THIS WEEKEND AS 700 MB TEMPERATURES ALONG THE I-25 CORRIDOR CLIMB
TO AROUND 18C.
MAXIMUM TEMPERATURES THIS WEEKEND OVER MANY SECTIONS OF THE
SOUTHEASTERN COLORADO PLAINS SHOULD REACH WELL INTO THE 90S THIS
WEEKEND. FINALLY...AS HAS BEEN THE CASE DURING THE PAST SEVERAL
DAYS...GENERALLY LIGHT GRADIENT WINDS SHOULD CONTINUE FROM
THURSDAY INTO NEXT TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1139 AM MDT WED AUG 14 2013
IFR STRATUS HAS BEEN QUICKLY DISSIPATING OVER THE PLAINS AND WON`T
INCLUDE ANY IN THE KPUB OR KCOS 18Z TAFS. MAINLY VFR CONDITIONS
EXPECTED TODAY AND TONIGHT WITH ISOLATED TO SCATTERED THUNDERSTORMS
DEVELOPING OVER THE MOUNTAINS THIS AFTERNOON THEN DRIFTING
EASTWARD ACROSS THE PLAINS DURING THE LATE AFTERNOON AND EVENING.
BRIEF MVFR CIGS/VIS WILL BE POSSIBLE WITH THUNDERSTORMS...ESPECIALLY
OVER THE PLAIN NEAR THE KS BORDER. WILL CONTINUE TO INCLUDE A VCTS
AT ALL TAF SITES LATE THIS AFTERNOON AND EARLY THIS
EVENING...ALTHOUGH TSRA SHOULD BE WEAKER AND MORE ISOLATED THAN
THE PAST FEW DAYS. MAIN IMPACT OF STORMS WILL BE GUSTY AND ERRATIC
OUTFLOW WINDS TO 40 KNOTS.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
503 AM MDT WED AUG 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 459 AM MDT WED AUG 14 2013
...DRIER AIRMASS MAKING PROGRESS EASTWARD TODAY...POTENTIAL FOR
STRONG STORMS OUT EAST THIS AFTERNOON...
SHORTWAVE MOVING DOWN EASTERN PERIPHERY OF THE UPPER RIDGE IS
KEEPING SCATTERED THUNDERSTORMS GOING ACROSS NORTHEAST/EAST CENTRAL
CO AS LOW LEVEL JET CONTINUES TO INCREASE ACROSS THE FAR EASTERN
PLAINS. KIOWA COUNTY IS MOST LIKELY TO BE CLIPPED BY THESE LATER
THIS MORNING AND FOLLOWED THE HRRR FOR POPS IN THE SHORT TERM AS IT
APPEARS TO BE THE MODEL HANDLING CURRENT CONVECTION BEST.
THUNDERSTORMS SHOULD DIMINISH OUT EAST LATER THIS MORNING.
MEANWHILE...DRIER AIRMASS OUT WEST WILL BE ADVANCING EASTWARD TODAY
WITH SHORT RANGE HIGH RES MODELS SHOWING DEW POINTS ACROSS THE
MOUNTAINS FALLING OFF INTO THE 20S AND 30S IN THE AFTERNOON. LCLS
RISE SUBSTANTIALLY AS A RESULT...AND WITH MORE INVERTED V SOUNDINGS
EXPECT EVAPORATION BELOW CLOUD BASES TO REDUCE PCPN EFFICIENCIES OF
THUNDERSTORMS SOME. HOWEVER...ERRATIC GUSTY WINDS WILL BECOME MORE
OF A THREAT AS A RESULT. MODELS STILL SHOW ENOUGH MOISTURE AND WEAK
FORCING MOVING THROUGH THE RIDGE ASSOC WITH UPPER LEVEL JET FOR
MAINLY ISOLATED AFTERNOON THUNDERSTORMS OUT WEST...WITH SCATTERED
THUNDERSTORMS ACROSS THE SE MTS/PLAINS DURING THE AFTERNOON. BUT
GIVEN THE LOWER THREAT FOR HEAVY RAINFALL...WILL NOT HOIST A FLASH
FLOOD WATCH FOR THE BURN SCARS IN EL PASO/TELLER COUNTIES. OF
COURSE...WALDO CANYON WILL NOT BE ENTIRELY OUT OF THE WOODS AS EVEN
WITH THE DRIER AIRMASS A QUICK .50 TO .75 OF RAIN WITH A STRONGER
STORM IS STILL POSSIBLE. BUT THIS LOOKS LIKE AN OUTLIER POSSIBILITY
FOR TODAY AND MORE LIKELY TO OCCUR FARTHER EAST WHERE GRADIENT OF
HIGHER DEW POINTS WILL BE LURKING. MEANWHILE...SFC DEW POINTS WILL
BE SLOWER TO DECREASE OUT ACROSS THE EASTERN PLAINS...AND NAM12
SHOWS AN AXIS OF 1500+ J/KG OF CAPE OUT OVER THE EASTERN PLAINS
OF KIOWA...BACA...BENT...AND PROWERS COUNTIES DURING THE LATE
AFTERNOON. DEEP LAYER SHEARS WILL BE RUNNING AROUND 35-40
KTS...SUFFICIENT FOR ONE OR TWO STRONG TO SEVERE THUNDERSTORMS.
LARGE HAIL AND DAMAGING WINDS WILL BE THE PRIMARY STORM THREATS AND
SPC HAS AREA OUTLOOKED UNDER A SEE TEXT. THUNDERSTORMS SHOULD
DIMINISH AFTER MIDNIGHT WITH LACK OF FORCING AND AXIS OF LOW LEVEL
JET PULLING AWAY TO THE EAST.
OTHERWISE...TEMPERATURES SHOULD BE A LITTLE WARMER TODAY FOR ALL
AREAS...WITH WITH DRIER SFC DEW POINTS OUT WEST...STARTING TO SEE A
RETURN OF LOWS IN THE 30S FOR SOME OF THE SPOTTY VALLEY LOCATIONS
DUE TO GOOD RADIATIONAL COOLING. LOWS ACROSS THE PLAINS WILL LIKELY
STAY IN THE 50S AND 60S WITH LEE TROFFING AND AXIS OF HIGHER DEW
POINTS HELPING TO KEEP MINS UP. -KT
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 459 AM MDT WED AUG 14 2013
METEOROLOGICAL CHALLENGES DURING THE LONGER TERM INCLUDE WARMER
TEMPERATURES...POTENTIAL STRONG TO SEVERE THUNDERSTORMS OVER FAR
EASTERN SECTIONS THURSDAY AND POPS.
IT STILL APPEARS THAT DRIER AND WARMER CONDITIONS WILL DEVELOP
OVER THE MAJORITY OF THE FORECAST DISTRICT FROM THURSDAY INTO THE
WEEKEND AS UPPER RIDGING BUILDS INTO THE FOUR CORNERS REGION BY THIS
WEEKEND. ALSO...LATEST PRECIPITABLE WATER VALUE PROJECTIONS DROP
TO BETWEEN 0.50 AND 0.70 INCHES OVER THE INTERSTATE 25 CORRIDOR
DURING THIS TIME-FRAME.
STRONG TO POSSIBLY SEVERE THUNDERSTORMS MAY ALSO DEVELOP OVER
PORTIONS OF THE FAR SOUTHEASTERN COLORADO PLAINS THURSDAY AS
PROJECTED LOCALIZED CAPES AND LIS NEARING 2000 J/KG AND -7C
RESPECTIVELY INTERACT WITH 0 TO 6 KM BULK SHEARS AROUND 40 KNOTS.
WFO PUEBLO WILL CONTINUE TO MONITOR CLOSELY.
GENERALLY ISOLATED AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS
ARE STILL ANTICIPATED OVER THE MAJORITY OF THE CWFA FROM THURSDAY
INTO EARLY SUNDAY. EVEN THOUGH RATHER UNLIKELY DURING THIS
TIME-FRAME...PLEASE REMEMBER THAT IF A STRONGER STORM DIRECTLY
IMPACTS A BURN SCAR...FLASH FLOODING WOULD BE POSSIBLE.
INCREASED SHOWER AND THUNDERSTORM ACTIVITY SHOULD THEN BE
NOTED...INITIALLY OVER WESTERN SECTIONS LATER SUNDAY AND THEN
CONTINUE INTO NEXT TUESDAY AS A NORTHERLY SURFACE ATTEMPTS TO
MOVE ACROSS EASTERN SECTIONS MONDAY AND ATMOSPHERIC MOISTURE
VALUES INCREASE. FORECAST MODEL SOUNDINGS PROJECT THAT
PRECIPITABLE WATER VALUES OVER THE INTERSTATE 25 CORRIDOR
INCREASE TO AROUND ONE INCH AT TIMES BY EARLY NEXT WEEK.
AT THIS TIME...IT STILL APPEARS THAT THE HIGHEST POTENTIAL FOR
LOCALIZED HEAVY RAIN AND ASSOCIATED FLASH FLOODING
CONCERNS(ESPECIALLY OVER THE AREA BURN SCARS) WILL BE POSSIBLE BY
NEXT MONDAY AND TUESDAY. AS ALWAYS...WFO PUEBLO WILL MONITOR
CLOSELY.
ABOVE SEASONAL AVERAGE MID-AUGUST MAXIMUM TEMPERATURES SHOULD BE
EXPERIENCED OVER THE MAJORITY OF THE FORECAST DISTRICT FROM
THURSDAY INTO NEXT TUESDAY WITH THE WARMEST CONDITIONS ANTICIPATED
THIS WEEKEND AS 700 MB TEMPERATURES ALONG THE I-25 CORRIDOR CLIMB
TO AROUND 18C.
MAXIMUM TEMPERATURES THIS WEEKEND OVER MANY SECTIONS OF THE
SOUTHEASTERN COLORADO PLAINS SHOULD REACH WELL INTO THE 90S THIS
WEEKEND. FINALLY...AS HAS BEEN THE CASE DURING THE PAST SEVERAL
DAYS...GENERALLY LIGHT GRADIENT WINDS SHOULD CONTINUE FROM
THURSDAY INTO NEXT TUESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 459 AM MDT WED AUG 14 2013
THREAT OF SOME MVFR STRATUS EXISTS ACROSS THE I-25 CORRIDOR THIS
MORNING AS WELL AS SOME PATCHY FOG ACROSS EL PASO COUNTY WHERE RAINFALL
OCCURRED YESTERDAY. THIS COULD AFFECT THE TERMINALS THIS MORNING BUT
SO FAR SATELLITE TRENDS HAVE KEPT STRATUS AND FOG WELL TO THE EAST
AROUND KLAA. PLAN TO KEEP A SCATTERED MVFR LAYER IN THE TAFS FOR
KCOS AND KPUB UNLESS TRENDS SUGGEST OTHERWISE. OTHERWISE...VFR
CONDITIONS EXPECTED THROUGH TODAY WITH ISOLATED TO SCATTERED
THUNDERSTORMS DEVELOPING OVER THE MOUNTAINS DURING THE AFTERNOON
BEFORE DRIFTING EASTWARD ACROSS THE PLAINS DURING THE LATE AFTERNOON
AND EVENING HOURS. LOCAL MVFR CIGS/VIS WILL BE POSSIBLE WITH
THUNDERSTORMS...PARTICULARLY TO THE EAST OF KLHX WHERE GREATER LOW
LEVEL MOISTURE WILL LINGER. TAF SITES HAVE MUCH LOWER CHANCE TODAY
OF BEING IMPACTED BY VCTS...THOUGH IF TS DEVELOPS NEARBY...GUSTY
OUTFLOW WINDS TO 40 KTS WILL BE POSSIBLE. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS ALBANY NY
959 PM EDT THU AUG 15 2013
.SYNOPSIS...
ANOTHER COOL NIGHT IS EXPECTED WITH COMFORTABLE HUMIDITY
LEVELS FOR MID AUGUST...AS HIGH PRESSURE WILL BE IN CONTROL. AN
UPPER LEVEL DISTURBANCE MAY INCREASE SOME CLOUDS NORTH OF THE
CAPITAL REGION WITH AN ISOLATED SHOWER OVER THE SOUTHERN ADIRONDACKS
TOMORROW. HIGH PRESSURE WILL CONTINUE THE FAIR WEATHER ON THE
WEEKEND WITH SEASONABLE TEMPERATURES.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AS OF 945 PM EDT...PATCHY HIGH CLOUDS CONTINUE TO OCCASIONALLY
PASS ACROSS CENTRAL AND SOUTHERN AREAS...IN ASSOCIATION WITH SOME
UPPER LEVEL MOISTURE STREAMING NORTHEAST. SOME MID LEVEL CLOUDS
ARE ALSO DEVELOPING ACROSS PORTIONS OF SOUTH CENTRAL NYS...AS MOISTURE
REMAINS TRAPPED BENEATH THE STRONG SUBSIDENCE INVERSION AROUND
780-800 MB. THE RUC 13 IMPLIES THAT THIS MOISTURE AND PATCHY
CLOUDS MAY REACH THE SOUTHEAST CATSKILLS...AND POSSIBLY THE MID
HUDSON VALLEY REGION OVERNIGHT. WILL NEED TO WATCH TRENDS. AT THIS
TIME...HAVE INDICATED CLEARING SKIES FOR MOST AREAS...WITH SOME
CLOUDS LINGERING ACROSS SOUTHERN AREAS...BUT THERE IS A
POSSIBILITY THAT THE AFOREMENTIONED MID LEVEL CLOUDS EXPAND
EASTWARD A BIT MORE THAN CURRENTLY FORECAST.
ASSUMING THAT MOST CLOUDS THIN/DECREASE...IDEAL RADIATIONAL
COOLING CONDITIONS SHOULD ALLOW TEMPS TO FALL BACK INTO THE 40S TO
L50S. THE L50S WILL TEND TO BE IN THE CAPITAL DISTRICT...MID
HUDSON VALLEY...SRN TACONICS...AND NW CT. HOWEVER...SHOULD THE
CLOUDS PERSIST/EXPAND...SOME PORTIONS OF THE SOUTHEAST CATSKILLS
AND MID HUDSON VALLEY MAY BE A BIT WARMER. SOME PATCHY RADIATIONAL
FOG OR MIST IS LIKELY...AND HAS BEEN CONTINUED IN THE GRIDDED AND
TEXT FORECASTS. THE MIN TEMPS WILL STILL BE 5 TO 10 DEGREES BELOW
NORMAL.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
FRIDAY...MOST OF THE REGION WILL HAVE ANOTHER VERY NICE MID-AUGUST
DAY. THE UPPER LEVEL TROUGH AXIS TIED TO THE UPPER LEVEL CENTERED
OVER E/NE QUEBEC WILL SWING ACROSS SRN QUEBEC...NRN NY AND NRN NEW
ENGLAND. THE SHORT-WAVE ENERGY IN THE CYCLONIC FLOW MAY TRIGGER
SOME ISOLD SHOWERS OR SPRINKLES OVER THE ADIRONDACKS. SOME SLIGHT
CHC POPS WERE USED OVER THE SRN DACK CORRIDOR /MAINLY NRN
HAMILTON...NRN HERKIMER...AND NWERN WARREN COUNTIES/. A MIXTURE OF
CLOUDS AND SUNSHINE WILL PERSIST CLOSER TO THE CAPITAL REGION.
H850 TEMPS WILL BE A SHADE BELOW NORMAL IN THE +10 TO +12C RANGE.
DECENT MIXING AND SOME SUNSHINE WILL ALLOW MAX TEMPS TO BE A
CATEGORY OR SO WARMER THAN TODAY...WITH HIGHS IN THE MID TO U70S
IN VALLEYS /A FEW 80F READINGS IN THE MID HUDSON AND CT VALLEYS/...
AND U60S TO L70S OVER THE HIGH PEAKS.
FRI NIGHT...A SFC ANTICYCLONE BUILDS BACK IN OVER NY AND NEW
ENGLAND WITH CONTINUED DRY WX. THE SUBSIDENCE FROM THE ANTICYCLONE
WILL YIELD CLEAR/MOSTLY CLEAR CONDITIONS AGAIN...WITH LIGHT TO
CALM WINDS. SOME PATCHY RADIATIONAL FOG/MIST IS POSSIBLE IN THE CT
RIVER VALLEY...LAKE GEORGE REGION...AND BERKS. LOWS IN THE M40S TO
L50S.
SATURDAY INTO SUNDAY...LOW AND MID LEVEL HEIGHTS WILL INCREASE
WITH RIDGING BUILDING IN FROM THE SOUTH AND WEST. A POSITIVELY
TILTED LONG-WAVE TROUGH WILL SET-UP OVER THE MS RIVER VALLEY. THE
SFC HIGH WILL DRIFT OFF THE NEW ENGLAND COAST TO OPEN THE
WEEKEND. TEMPERATURES RISE CLOSER TO NORMAL WITH WEAK WARM
ADVECTION ALOFT. THE GFS HAS H850 TEMPS CLOSE TO THE +12C TO +13C
RANGE. MAX TEMPS ARE FORECASTED CLOSE TO A GFS/ETAMOS BLEND WITH
HIGHS IN THE U70S TO L80S IN THE VALLEYS...AND OVER THE
HILLTOWNS...AND 70S OVER THE MTNS. HUMIDITY LEVELS WILL INCREASE
SATURDAY NIGHT INTO SUNDAY. THEY SHOULD NOT BE UNBEARABLE...BUT
SFC DEWPTS WILL INCREASE TO THE U50S TO L60S. A DISTURBANCE MOVING
ALONG A FRONTAL BOUNDARY ACROSS THE MID ATLANTIC REGION APPEARS IT
WILL STAY SOUTH OF THE FCST AREA TO CLOSE THE WEEKEND. MID AND
HIGH CLOUDS WILL INCREASE...BUT THE FAIR AND DRY WX LOOKS TO
CONTINUE BASED ON THE SHORT/MEDIUM RANGE GUIDANCE WITH HIGHS STILL
NEAR NORMAL FOR MID- AUGUST.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
THE LONG RANGE STILL LOOKS DRY WITH ABOVE NORMAL TEMPERATURES. A
BROAD AREA OF HIGH PRESSURE AT THE SURFACE AND ALOFT WILL BE IN
CONTROL.
THERE WILL BE PLENTY OF MOISTURE LURKING TO THE SOUTH OF OUR
REGION...SOME OF WHICH MIGHT BE ASSOCIATED WITH A POSSIBLE TROPICAL
SYSTEM EMERGING FROM THE GULF OF MEXICO. HOWEVER...SO FAR...ALL
MODELS KEEP ANY DEEP MOISTURE TO OUR SOUTH. THE 12Z GFS DOES TRY TO
BRING SOME SHOWERS TO OUR SOUTHERN AREAS LATE MONDAY. HOWEVER...THE
12Z ECMWF KEPT ALL MOISTURE FURTHER SOUTH. HAVE DECIDED TO KEEP ALL
PERIODS DRY.
OVERALL...LOOK FOR PARTLY TO MOSTLY SUNNY WARM DAYS WITH A SLOW
INCREASE IN HUMIDITY...AND CLEAR TO PARTLY CLOUDY NIGHTS. DAYTIME
HIGHS WILL START OFF IN THE UPPER 70S NORTHWEST TO MID 80S
SOUTH...WARMING TO AROUND 80 NORTHWEST TO NEAR 90 SOUTH BY
THURSDAY.
OVERNIGHT LOWS WILL BE START FROM THE MID 50S IN OUTLYING AREAS...TO
LOWER 60S IN THE CAPITAL REGION...WARMING TO AROUND 60 TO THE UPPER
60S TOWARD THE END OF THE PERIOD.
&&
.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
HIGH PRESSURE OVER THE GREAT LAKES AND OHIO VALLEY REGION WILL
SPREAD EASTWARD TOWARDS THE NORTHEAST OVER THE NEXT FEW DAYS.
MAINLY VFR CONDITIONS ARE EXPECTED THIS EVENING...AND AGAIN FOR
MUCH OF FRIDAY. HOWEVER...A FEW PERIODS OF MVFR/IFR VSBYS WILL BE
POSSIBLE LATER TONIGHT AT KGFL AND KPSF AS PATCHY GROUND FOG
DEVELOPS. THE BEST CHANCE FOR THIS SHOULD BE BETWEEN ROUGHLY 08Z-
11Z...ALTHOUGH COULD START EVEN EARLIER AT KGFL.
OTHERWISE...ON FRIDAY...ANOTHER GOOD FLYING DAY WITH UNRESTRICTED
VISIBILITY...AND ONLY FEW-SCT CU CLOUDS DEVELOPING AROUND 6 KFT
ALONG WITH OCCASIONAL HIGH CLOUDS.
LIGHT WEST WINDS WILL DECREASE TO LESS THAN 5 KT OVERNIGHT...THEN
INCREASE SLIGHTLY FROM THE WEST TO SOUTHWEST AT 5-10 KT FROM LATE
FRI MORNING INTO THE AFTERNOON HOURS.
OUTLOOK...
FRI NIGHT-TUE: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
HIGH PRESSURE WILL MAINLY BE IN CONTROL THE NEXT SEVERAL DAYS
INTO EARLY NEXT WEEK.
RELATIVE HUMIDITIES WILL RECOVER TO ABOUT 100 PERCENT FRIDAY
MORNING. HEAVY DEW IS LIKELY AGAIN. THE RH VALUES WILL LOWER TO 35
TO 50 PERCENT TOMORROW AFTERNOON...AND THEN RECOVER CLOSE TO 100
PERCENT SATURDAY MORNING WITH MORE DEW POSSIBLE.
THE WINDS ARE EXPECTED TO BE PREDOMINATELY LIGHT AT LESS THAN 10
MPH INTO WEEKEND.
&&
.HYDROLOGY...
THE NEXT 5 DAYS WILL FEATURE MAINLY DRY WEATHER WITH HIGH
PRESSURE IN CONTROL. NO HYDRO PROBLEMS ARE ANTICIPATED WITH FLOWS
RETURNING TO NORMAL AUGUST LEVELS.
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...KL/WASULA
SHORT TERM...WASULA
LONG TERM...HWJIV
AVIATION...HWJIV/KL
FIRE WEATHER...WASULA
HYDROLOGY...IAA/WASULA
AREA FORECAST DISCUSSION...UPDATED FOR AVIATION
NWS PEACHTREE CITY GA
209 AM EDT WED AUG 14 2013
.UPDATE...
COLD FRONT CURRENTLY ACROSS NORTHERN GA THIS EVENING. A FEW
SHOWERS HAVE DEVELOPED BEHIND THE BOUNDARY...BUT THEY HAVE BEEN
SHORT LIVED. STORMS ARE MORE NUMEROUS SOUTH OF THE METRO
AREA...WHERE ACTIVITY KEEPS MOVING IN FROM EASTERN AL. THE ATMOS
ACROSS PORTIONS OF CENTRAL AND SOUTHERN GA WILL REMAIN UNSTABLE
FOR THE NEXT FEW HOURS. CONVECTION SEEMS TO MOSTLY BE OUTFLOW
DRIVEN. DO EXPECT STORMS TO DIMINISH WITH THE LOSS OF
HEATING AND MOSTLY BE GONE BY MIDNIGHT. THE HRRR SUPPORTS THIS.
MAY HAVE TO DO ADDITIONAL UPDATES TO THE POPS ACROSS NORTHERN
GA...MAINLY AREAS NORTH OF THE FRONT...LATER TONIGHT.
&&
.PREV DISCUSSION... /ISSUED 325 PM EDT TUE AUG 13 2013/
SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
SHORT RANGE MODELS CONTINUE TO SHOW A COLD FRONT...CURRENTLY ACROSS
TN... SAGGING ACROSS NORTH GA TONIGHT AND STALLING ACROSS CENTRAL GA
WEDNESDAY AFTERNOON. REGIONAL RADARS SHOW SCATTERED SHOWERS AND
THUNDERSTORMS BEGINNING TO DEVELOP ACROSS THE FORECAST AREA AS AN
UPPER DISTURBANCE APPROACHES FROM THE WEST. EXPECT A WEAK SURFACE
TROUGH TO HELP PROVIDE A FOCUS ACROSS NORTH GA THIS AFTERNOON AND
RADAR TRENDS SUPPORT THAT...WITH A SCATTERED LINE OF CONVECTION
DEVELOPING FROM WEST OF ROME...EASTWARD TO JASPER AND CLEVELAND.
EXPECT THIS ACTIVITY TO SAG SOUTHWARD THROUGH THE LATE AFTERNOON AND
EVENING HOURS. ADDITIONAL SCATTERED TO NUMEROUS CONVECTION IS
DEVELOPING ACROSS PARTS OF CENTRAL GA WHERE THE GREATER
INSTABILITIES AND DEEPER MOISTURE ARE POOLED. THE HRRR MODEL
CLUSTERS MOST OF THE CONVECTIVE ACTIVITY ACROSS THE CENTRAL ZONES...
FROM AREAS AROUND COLUMBUS TO MACON TO MILLEDGEVILLE AND SOUTHWARD
DURING THE LATE AFTERNOON AND EVENING HOURS. THUNDERSTORM ACTIVITY
MAY PERSIST THROUGH MID EVENING BEFORE DIMINISHING TO MAINLY
SHOWERS. SCATTERED SHOWERS MAY PERSIST OVERNIGHT ALONG AND AHEAD OF
THE COLD FRONT... BUT ANY THUNDERSTORM ACTIVITY SHOULD BE VERY
ISOLATED AT BEST OVERNIGHT. THE MAIN THUNDERSTORM THREAT THROUGH THE
EVENING WILL CONTINUE TO BE LOCALLY HEAVY RAIN AND POSSIBLE BRIEF
FLOODING. HOWEVER... WITH 2500-3000 CAPE... CANNOT RULE OUT A PULSE
STRONG STORM PRODUCING WIND GUSTS TO 40-45 MPH AND POSSIBLY SOME
SMALL HAIL. MODELS AGREE ON DRIER AIR SPREADING IN BEHIND THE FRONT
ACROSS NORTH GA BY EARLY WEDNESDAY... SO WILL SHOW THE GREATER RAIN
CHANCES ACROSS CENTRAL GA ON WEDNESDAY...AND MAINLY ALONG AND SOUTH
OF A LA GRANGE TO WARRENTON LINE...WITH ONLY A LOW CHANCE IN THE
ATLANTA METRO AREA FOR WEDNESDAY AFTERNOON. LOCALLY HEAVY RAIN WILL
REMAIN A THREAT ACROSS CENTRAL GA WEDNESDAY AFTERNOON AS THE FRONT
PROVIDES A FOCUS FOR TRAINING CONVECTION. MODELS SHOW GENERALLY ONE
QUARTER TO ONE HALF INCH FROM COLUMBUS TO MACON AND SOUTHWARD ON
WEDNESDAY... BUT ISOLATED HIGHER AMOUNTS OF 1 TO 3 INCHES ARE
POSSIBLE. ALTHOUGH CANNOT RULE OUT A PULSE STRONG TO SEVERE STORM
ALONG OR SOUTH OF THE FRONT WEDNESDAY AFTERNOON... NOT EXPECTING
ANYTHING WIDESPREAD AND THE GREATER STRONG STORM THREAT SHOULD BE
JUST SOUTH OF THE FORECAST AREA WEDNESDAY AFTERNOON AND EVENING.
OTHERWISE... AS FOR TEMPS A MODEL BLEND THROUGH THE SHORT TERM
LOOKED REASONABLE.
39
LONG TERM /THURSDAY THROUGH TUESDAY/...
GUIDANCE CONTINUES TO POINT TO A WET EXTENDED PERIOD. AS THE FRONT
SAGS SOUTH OF THE AREA TROUGH THE SHORT TERM...SURFACE HIGH UNDER
CONFLUENT FLOW ALOFT WILL SLIP EAST AND ACROSS THE APPALACHIANS IN
A HYBRID DAMMING EVENT. THE QUESTION WILL BE HOW MUCH GULF
MOISTURE WILL INTERACT WITH THE DAMMING. FOR THURSDAY...WITH THE
STALLED FRONT AND ONSET OF HYBRID CAD...HPC AND SYNOPTIC MODELS
KEEP THE BEST PRECIP ACROSS CENTRAL GEORGIA...WITH A GOOD INCH OF
BASIN-AVERAGE QPF DURING THE DAY. THIS TREND CONTINUES INTO
FRIDAY. BESIDES THE PRECIP HOWEVER...THE BIGGEST SENSIBLE IMPACT
WILL BE TEMPS. CURRENT HIGH TEMPS FOR THURSDAY THROUGH SATURDAY DO
NOT BRING NORTH GEORGIA OUT OF THE 70S...AND REALLY ONLY INTO THE
MID 80S IN SOUTHERN ZONES. POSSIBLY A SLIGHT WARMING TREND BY A
DEGREE OR SO ON SUNDAY BUT THIS REMAINS TO BE SEEN. THESE FORECAST
MAX TEMPS ARE A GOOD 10 DEGREES COOLER THAN SEASONAL NORMALS...
THE KIND OF IMPACTS NORMALLY SEEN WITH CLASSICAL CAD RATHER THAN
HYBRID CAD.
00Z ECMWF CONTINUES TO TAKE THE TROPICAL WAVE /CURRENTLY IN THE
CARIBBEAN/ FURTHER WEST TOWARD THE YUCATAN...WHILE GFS AND
CANADIAN BRING IT INTO THE GULF AND CLOSE TO THE COAST FRIDAY
NIGHT. FOR WHAT ITS WORTH...THE CANADIAN IS STRONGER AND FURTHER
WEST WITH THE SURFACE LOW THAN THE GFS...WHICH WOULD POSSIBLY
INDICATE SEVERE POTENTIAL ON SATURDAY...BUT IT IS A BIT OF AN
OUTLIER THERE. ECMWF IS DRIEST WHILE GFS/CMC ARE WETTER
SOLUTIONS. HPC NOT GOING NEARLY AS HIGH AS THE GFS BUT EVEN
SO...WITH THE PROLONGED WET PERIOD ACROSS ESPECIALLY CENTRAL
GEORGIA FROM THE SHORT TERM FRONT...THERE IS SOME CONCERN ABOUT
THE RAINFALL PILING UP. HAVE NOT DONE A COMPLETE DIAGNOSIS TO
DETERMINE IF THE THURSDAY-FRIDAY RAIN WOULD QUALIFY AS A PRE
/PREDECESSOR RAINFALL EVENT/ BUT IN ANY CASE THE 7-DAY QPF TOTAL
FROM HPC ARE UPWARDS OF 6 INCHES ACROSS PORTIONS OF CENTRAL
GEORGIA. THIS BEING BASIN-AVERAGE...IMPLYING THAT SOME AREAS
COULD GET SUBSTANTIALLY MORE /AND OF COURSE SOME AREAS
SUBSTANTIALLY LESS/. ALL INTERESTS SHOULD STAY TUNED TO LATEST
FORECASTS AS THIS IS REFINED OVER THE NEXT FEW DAYS.
SO OVERALL...REALLY MADE ONLY MINOR CHANGES TO PREVIOUS EXTENDED
FORECAST. REFINED AND ADDED SOME DETAIL TO DAYS 4 AND 5 ESPECIALLY
WITH TEMPS WINDS AND DEWPOINTS /VERY LITTLE IF ANY CHANGE TO
POPS/ AND MADE SOME MINOR ADJUSTMENTS TO HIGH TEMPS THROUGH THE
REST OF THE PERIOD TO REFLECT THE PROLONGED COOL SPELL.
TDP
&&
.AVIATION...
06Z UPDATE...
A WEAK COLD FRONT CONTINUES TO SLOWLY MOVE INTO THE NORTH SIDE OF
THE ATLANTA METRO AREA AT THIS TIME. IFR CIGS SHOWING UP IN AREAS
THAT HAD RAIN ON TUESDAY...OTHERWISE GENERALLY VFR CIGS ARE
EXPECTED...BUT WILL MONITOR CLOSELY AROUND SUNRISE. THE RAP13 MODEL
INDICATES THE FRONT WILL CONTINUE MOVING SOUTH TODAY...BUT WILL
LIKELY STALL OUT JUST SOUTH OF CSG AND MCN. SCATTERED TSTMS EXPECTED
AROUND THE FRONTAL ZONE THIS AFTERNOON AND EARLY EVENING...THIS
WOULD BE BASICALLY ATL-AHN SOUTHWARD. A LIGHT W-NW WIND THIS MORNING
SHIFTING TO NE AFTER FRONTAL PASSAGE.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM CONFIDENCE ON ALL ELEMENTS.
16
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 69 88 68 78 / 30 40 20 30
ATLANTA 70 86 69 79 / 30 30 20 50
BLAIRSVILLE 64 81 64 76 / 20 20 20 30
CARTERSVILLE 68 86 64 82 / 20 20 20 30
COLUMBUS 73 87 71 84 / 30 60 40 80
GAINESVILLE 69 85 68 76 / 20 20 20 30
MACON 72 89 71 82 / 40 60 50 80
ROME 68 89 63 83 / 20 20 10 30
PEACHTREE CITY 70 86 66 79 / 30 40 20 50
VIDALIA 74 88 71 84 / 50 60 60 80
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1125 PM CDT Tue Aug 13 2013
.SHORT TERM...(This Evening through Wednesday)
Issued at 328 PM CDT TUE AUG 13 2013
Upper trough remains over the Great Lakes with a shortwave trough
extending southwestward into eastern Nebraska. This shortwave along
with a well defined MCV in southern Nebraska helped sustain a
cluster of showers and thunderstorms into the far northwest corner
of the CWA this afternoon. However...a drier and more stable
atmosphere over most of the CWA has aided a weakening trend to the
convection and expect any sustained or additional development to
occur in the western or far southern CWA until early evening. At
that time...feel majority of convection...now occurring in central
KS will have advanced further south of the vicinity with the outflow
boundary...similar to the HRRR model. Will therefore carry a dry
forecast for the overnight. Skies may become mostly clear tonight which
would support the possibility of some patchy fog. However...feel the
potential for more high clouds to advance into the area from the
northwest is high enough to negate mentioning fog for now. The dry
air and breaks in the clouds should help lows fall into the lower
60s.
On Wednesday...will maintain a dry forecast as the deeper moisture and
axis of higher instability are pushed more to the west of the CWA.
Any convection through the day should remain to the west and north
of the CWA. High temperatures Wednesday will be similar
today...except slightly warmer in the north central with readings
in the lower 80s.
.LONG TERM...(Wednesday Night through Tuesday)
Issued at 328 PM CDT TUE AUG 13 2013
For Wednesday night through Friday, the models have trended more
along the lines of the NAM with keeping much of the cooler and
dryer air to the northeast of the forecast area. On top of that
instead of a distinct shortwave trough moving through the
northwest flow Thursday night, models have trended towards
bringing several vort maximum through the flow late Wednesday
night through Friday. Because of this have trended min temps
warmer expecting more cloud cover and higher dewpoint temps
through the night. Will also carry a 20 to 30 percent chance pops
through the period. Forecast soundings with the higher dewpoints
show much less inhibition to convection with lower LCL heights.
because of this it is difficult to rule out precip chances with
the expected vort energy moving overhead. The airmass in general
does not change much from today. Therefore expect temps to be
relatively persistent with highs around 80 and lows in the lower
to mid 60s.
Saturday into Monday is expected to be dry with a gradual warming
trend as mid level ridging moves in from the west and insolation
increases. Uncertainty remains in the forecast for next week as
the ECMWF has shown little consistency from run to run over the
last 48 hrs. Think that there will be a small chance for precip
Monday night and Tuesday as the GFS continues to bring a shortwave
trough across the plains. However confidence is not high since the
ECMWF goes back and forth between cutting off an upper low and an
open shortwave.
&&
.AVIATION...(For the 06Z TAFs through 06Z Wednesday Night)
Issued at 1123 PM CDT TUE AUG 13 2013
High clouds clearing over western areas at this writing with next
batch of high clouds still in northern Nebraska. Will therefore
add some MVFR visby restrictions to TOP and MHK. Winds turn to the
SE tomorrow and added a group for ending of BR to account for
this.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...63
LONG TERM...Wolters
AVIATION...67
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
1036 AM EDT WED AUG 14 2013
.SYNOPSIS...
A TROUGH OF LOW PRESSURE WILL CROSS THE REGION TODAY AND WILL PUSH
OFFSHORE THIS EVENING. HIGH PRESSURE WILL BUILD SOUTH OF NEW ENGLAND
TONIGHT THROUGH THURSDAY. A WEAK COLD FRONT WILL SETTLE INTO
NORTHERN NEW ENGLAND ON FRIDAY AS HIGH PRESSURE HOLDS SOUTH OF NEW
ENGLAND. HIGH PRESSURE WILL REMAIN IN PLACE SOUTH OF THE REGION
SUNDAY AND MONDAY. A COLD FRONT WILL APPROACH FROM THE NORTHWEST ON
TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...COLD FNT IS ALIGNED ALONG SWRN ME COAST UP THROUGH THE
CAPITAL DISTRICT ATTM. PRIMARY S/WV TROF CONTINUES TO SPIN THRU
THE ST. LAWRENCE VALLEY...WHILE SECONDARY LOBE CROSSES THE
ADIRONDACKS. THIS UPPER TROF WILL SWING ACROSS NRN NEW ENGLAND
TODAY...PROVIDING THE LIFT FOR SCT SHRA AND TSTMS. COLD AIR ALOFT
WILL PROVIDE AN IDEAL SITUATION FOR SMALL HAIL IN ANY OF THE
STRONGER STORMS. HRRR CONTINUES TO ADVERTISE A BAND OF CONVECTION
FORMING ALONG INTERIOR WRN ME...AND SWEEPING TOWARDS THE COAST.
THIS WILL BE THE MOST LIKELY AREA FOR STRONGER STORMS AND HAIL.
PREVIOUS DISCUSSION...
A STRONG SHORT WAVE TROUGH WILL MOVE ACROSS NORTHERN NEW ENGLAND
TODAY. AT THE SURFACE...LOW PRESSURE WILL HEAD UP INTO NEW
BRUNSWICK LATER THIS MORNING WITH A TRAILING COLD FRONT HUGGING
THE MAINE COAST UNTIL IT PUSHES OFF SHORE EARLY AFTERNOON. SHOWERS
AND POTENTIALLY A FEW THUNDERSTORMS ARE EXPECTED TO DEVELOP IN THE
VICINITY OF THIS FRONTAL BOUNDARY...WITH THE BEST CHANCES ON THE
MID COAST OF MAINE AND NORTHWARD.
OTHERWISE...COLD MID LEVEL AIR TO THE TUNE TO -17 TO -20C AT 500MB
WILL ADVECT INTO THE REGION. THIS WILL DECREASE STABILITY AND
LIKELY AID IN THE DEVELOPMENT OF AT LEAST WDLY SCT SHOWERS
ELSEWHERE...ESPECIALLY IN THE MOUNTAINS. HOWEVER...A GOOD DEAL OF
SUN SHOULD BE SEEN TODAY AFTER THE EARLY MORNING STRATUS AND FOG
BURNS OFF.
WESTERLY WINDS WILL BECOME GUSTY THIS AFTERNOON IN THE WAKE OF THE
FRONT...WITH A FEW GUSTS AROUND 25 MPH LIKELY. TEMPERATURES WILL
HOLD IN THE 60S IN THE MOUNTAINS...WITH 70S ELSEWHERE.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
BREEZY CAA REGIME TONIGHT WITH MOSTLY CLEAR SKIES. HOWEVER...MOIST
CYCLONIC FLOW SHOULD KEEP THE NRN NH AND WRN ME MOUNTAINS IN A
FAIR AMOUNT OF CLOUDS. ANOTHER SHORT WAVE THROUGH APPROACHES
THURSDAY BUT ANY SHOWER ACTIVITY SHOULD REMAIN JUST NORTH OF THE
BORDER IN QUEBEC.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
FAIRLY QUIET IN THE MID TERM AND EXTENDED FORECAST AS HIGH
PRESSURE BUILDS SOUTH OF NEW ENGLAND THURSDAY NIGHT AND FRIDAY. A
WEAK BACKDOOR COLD FRONT WILL DIP INTO NORTHERN NEW ENGLAND ON
FRIDAY BUT SHOULD NOT RESULT IN MUCH MORE THAN A FEW PASSING
CLOUDS. AFTER SOME CHILLY OVERNIGHT LOWS THURSDAY NIGHT SHOULD SEE
TEMPS REBOUND INTO THE LOWER TO MID 70S IN THE NORTH AND UPPER 70S
TO LOWER 80S IN THE SOUTH.
HIGH PRESSURE WILL REMAIN ANCHORED SOUTH OF NEW ENGLAND THROUGH THE
WEEKEND PROVIDING MOSTLY SUNNY SKIES AND SEASONABLE TEMPS. WILL SEE
HIGHS BOTH DAYS SIMILAR TO FRIDAY WITH A SLIGHT MODERATION IN TEMPS
ON SUNDAY AS WARMER AIR IS TRANSPORTED INTO THE THE REGION FROM THE
WEST.
HIGH PRESSURE WILL REMAIN IN CONTROL MONDAY AND TUESDAY AND WILL
BEGIN PUMPING WARMER AND MORE HUMID AIR BACK INTO THE REGION. BY
TUESDAY HIGHS WILL TOP OUT IN THE LOWER TO MID MID 80S ACROSS MUCH
OF THE FORECAST AREA ASIDE FROM MID COAST MAINE WERE AN ONSHORE
BREEZE WILL HOLD HIGHS IN THE 70S. A COLD FRONT APPROACHING FROM THE
NORTHWEST WILL BRING INCREASING CLOUDS AND A CHANCE OF SHOWERS AND
THUNDERSTORMS TO NORTHERN ZONES IN THE AFTERNOON.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM...IFR OR LOWER CONDITIONS IS STRATUS AND FOG EARLY THIS
MORNING WILL GIVE WAY TO VFR CONDITIONS DURING THE MORNING HOURS.
A FEW SHOWERS AND POTENTIALLY ISOLD THUNDERSTORMS WILL BE
POSSIBLE...ON THE MID COAST OF MAINE. OTHERWISE...GUSTY NW WINDS
WILL KICK IN THIS AFTERNOON...WITH A FEW GUSTS AROUND 25 KT
LIKELY. VFR CONDITIONS ARE EXPECTED TONIGHT AND THURSDAY.
LONG TERM...VFR THURSDAY NIGHT THROUGH SUNDAY.
&&
.MARINE...
SHORT TERM...SCA HOISTED FOR ALL WATERS FOR THIS AFTERNOON AND
EVENING AS LOW PRESSURE STRENGTHENS TO OUR NORTHEAST. A STRONG CAA
PATTERN WILL LIKELY BRING 25 KT GUSTS TO THE WATERS THIS AFTERNOON
AND EVENING. WITH THE OFFSHORE FLOW IN PLACE...SEAS WILL NOT BE
MUCH OF AN ISSUE ALTHOUGH A FEW 5 FOOTERS WILL BE POSSIBLE ON THE
OUTER WATERS.
LONG TERM...NO PROBLEMS EXPECTED.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO MIDNIGHT EDT
TONIGHT FOR ANZ150>154.
&&
$$
NEAR TERM...LEGRO
AREA FORECAST DISCUSSION
NWS CARIBOU ME
630 AM EDT WED AUG 14 2013
.SYNOPSIS...
LOW PRESSURE WILL TRACK FROM THE SAINT JOHN VALLEY TODAY INTO GULF OF
SAINT LAWRENCE TONIGHT...BRINGING A COLD FRONT ACROSS THE REGION ALONG
WITH ADDITIONAL SHOWERS AND POSSIBLE THUNDERSTORMS. ANOTHER COLD FRONT
FROM NORTHERN CANADA WILL APPROACH LATE THURSDAY AND THEN BECOME
STATIONARY ACROSS FAR NORTHERN PORTIONS OF THE REGION ON FRIDAY. HIGH
PRESSURE WITH FAIR CONDITIONS WILL RETURN FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
630 AM UPDATE...THE PREVIOUS FORECAST STILL LOOKS PRETTY MUCH ON
TRACK. MUCH OF THE SHOWER ACTIVITY HAS ENDED ACROSS THE FORECAST
AREA EARLY THIS MORNING, SO PULLED BACK POPS A BIT FOR THE NEXT
FEW HOURS. THE LATEST MODEL GUIDANCE INCLUDING THE HRRR AND
RUC/RAP STILL INDICATE SHOWERS WILL REDEVELOP BY MID MORNING.
OTHERWISE, NO SIGNIFICANT CHANGES WERE NEEDED.
PREVIOUS DISCUSSION...
THE CONCERN FOR TODAY IS THE POTENTIAL FOR STRONG STORMS WITH
SMALL HAIL AND GUSTY WINDS.
THE UPPER TROUGH THAT IS CURRENTLY POSITIONED OVER EASTERN ONTARIO
WILL DEEPEN AS IT LIFTS NORTHEASTWARD TODAY. MEANWHILE, THE SURFACE
LOW WILL SLIDE ACROSS NORTHERN MAINE, DRAGGING A SURFACE
BOUNDARY/COLD FRONT THROUGH THE FORECAST AREA AS IT DOES SO. WITH
THE COLD POOL ASSOCIATED WITH THE UPPER LOW MOVING IN OVERHEAD,
LAPSE RATES WILL STEEPEN TO 6-7 C/KM WITH LIFTED INDICES OF -4 TO
-5C. FREEZING LEVELS WILL DROP TO AROUND 9 KFT, ENHANCING THE
POTENTIAL FOR HAIL. A JET WORKING AROUND THE BOTTOM OF THE DIGGING
UPPER TROUGH WILL ALLOW FOR IMPRESSIVE SHEAR; 0-6KM BULK SHEAR
LOOKS TO REACH 40-50 KT OR BETTER. ALL THIS POINTS TO THE
POTENTIAL FOR STRONG TO POSSIBLY SEVERE STORMS THIS AFTERNOON. THE
FLY IN THE OINTMENT WILL BE SURFACE INSTABILITY. SURFACE-BASED
CAPES WILL DEPEND HEAVILY UPON HOW MUCH SUNSHINE IS ABLE TO BREAK
THROUGH THE CLOUDS. WATER VAPOR IMAGERY DOES INDICATE SOME DRIER
AIR WORKING AROUND THE SOUTHERN SIDE OF THE TROUGH, WHICH SHOULD
ALLOW FOR SKIES TO BECOME PARTLY SUNNY FOR AT LEAST THE SOUTHERN
HALF OF THE FORECAST AREA. THE QUESTION THEN BECOMES ONE OF
TIMING, AS TO HOW LONG THE ATMOSPHERE HAS TO DESTABILIZE BEFORE
THE AFOREMENTIONED BOUNDARY MOVES ACROSS THE REGION. THE LATEST
RUC/RAP, WHICH WAS FAVORED FOR ITS TIMING/PLACEMENT OF PRECIP
THROUGH THIS EVENING, SHOWS CAPES REACHING 1000+ J/KG, MAINLY
ACROSS EASTERN AND SOUTHERN AREAS AWAY FROM THE COAST. THE NAM IS
SIMILAR IN PLACEMENT BUT MORE ROBUST IN AMOUNTS, RANGING FROM
1200-1400 J/KG. MEANWHILE THE GFS IS NOT AS OPTIMISTIC AND KEEPS
CAPES BELOW 900 J/KG. LONG STORY SHORT...SCATTERED STRONG STORMS
ARE POSSIBLE THIS AFTERNOON, SOME OF WHICH MAY APPROACH SEVERE
LEVELS, MAINLY SOUTH AND EAST OF A MONTICELLO...MILLINOCKET
DOVER-FOXCROFT LINE. GIVEN THE UNCERTAINTY IN INSTABILITY,
THERE WAS NOT ENOUGH CONFIDENCE TO ADD SEVERE-TYPE WORDING TO THE
FORECAST. HOWEVER, THE ENHANCED WORDING FOR STRONG STORMS THAT WAS
INTRODUCED YESTERDAY IS STILL WARRANTED GIVEN THE ABOVE THINKING.
OPTED TO INCLUDE THE ENHANCED WORDING EVEN IN THE NORTH AND WEST,
THOUGH THE WINDOW FOR STRONG STORMS IS MUCH SMALLER THERE; CLOUD
COVER WILL BE TOUGHER TO BREAK UP IN TIME FOR ENOUGH
SUNSHINE/DESTABILIZATION PRIOR TO FRONTAL PASSAGE TO ALLOW FOR
ORGANIZED STORMS. BUT CAN`T TOTALLY RULE OUT A STRONG STORM OR
TWO.
THE FRONT WILL EXIT INTO NEW BRUNSWICK THIS EVENING, QUICKLY ENDING
THUNDERSTORM POTENTIAL FROM WEST TO EAST THROUGH THE AFTERNOON.
EXPECT THE PRECIPITATION WILL COME TO AN END BY MIDNIGHT AS DRIER
AIR RUSHES IN BEHIND THE FRONT. EXPECT SKIES WILL BECOME PARTLY TO
MOSTLY CLEAR AFTER MIDNIGHT, WITH OVERNIGHT LOWS RANGING FROM THE
MID 40S IN THE NORTH TO AROUND 50 DOWNEAST.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
THU WILL BEGIN MSLY SUNNY AND BREEZY ACROSS THE FA...BUT ANOTHER
S/WV ALG WITH AN APCHG COLD FRONT WILL BRING SOME INCREASE IN
CLDNSS FOR CNTRL AND SPCLY NRN PTNS OF THE FA LATE IN THE DAY AND
EVE...WITH A SLGT CHC OF SHWRS. ANY SHWRS SHOULD DISSIPATE LATE
THU NGT. FRI WILL AGAIN BEGIN FAIR...BUT WITH THE COLD FRONT
BECOMING STATIONARY OVR NRN PTNS OF THE FA. AN UPPER LVL TROF
CROSSING THIS PTN OF THE REGION FRI AFTN WILL ACT AS A FOCUS FOR
AFTN AND ERLY EVE SHWRS OVR CNTRL AND SPCLY NRN PTNS OF THE FA
WHERE WE GO WITH CHC TO HI CHC POPS. FCST SBCAPES OF 100-200 J/KG
FOR THESE PDS DO NOT YET SUPPORT TSTMS IN THE FCST...BUT THIS WILL
NEED TO BE MONITORED. IN ANY EVENT...WITH LITTLE IN THE WAY OF
AVAILABLE LLVL MOISTURE ALG WITH FAST FORWARD MOTION...QPF WILL BE
LGT WITH THESE SHWRS. SHWRS SHOULD DISSIPATE QUICKLY AFT SUNSET
WITH THE LOSS OF DAYTIME HTG AND LOW TO MID LVL INSTABILITY AS THE
UPPER TROF QUICKLY MOVES E INTO THE MARITIMES. THIS WILL ALLOW SFC
HI PRES TO BUILD ACROSS THE FA FROM CNTRL CAN LATE FRI NGT.
BOTH HI AND LOW TEMPS WILL BE COOLER THAN SEASONAL NORMS DURG THE
SHORT RANGE...WITH THE COOLEST TEMPS ERLY SAT MORN. WE DID BACK
OFF A COUPLE OF DEG F FROM THE LOWEST TEMPS XPCTD OVR NW VLYS...
DUE TO UNCERTAINTY AS TO HOW LONG CLDNSS FROM THE DEPARTING UPPER
TROF LASTS INTO FRI EVE. WITH AN ELONGATED W-E SFC HI PRES OVR THE
REGION SAT...TEMPS SHOULD MAKE A MARKED RECOVERY FROM CHILLY LOW
TEMPS TO JUST BLO SEASONAL NORMS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
AFT A COOL NGT SAT NGT...BUT NOT AS COOL AS FRI NGT...HI TEMPS
WILL BEGIN A WARMING TREND SUN...EVENTUALLY YIELDING TO ABV NORMAL
HI TEMPS AND CONTD MODERATING LOW TEMPS ERLY NEXT WEEK AS THE SFC
HI SLOWLY DRIFTS S INTO THE GULF OF ME IN RESPONSE TO SPLIT FLOW...
FLAT UPPER LVL RIDGING OVR NRN NEW ENG...ALLOWING A RETURN WSW
LLVL FLOW REGIME TO THE REGION. IN FACT... HI TEMPS WILL LIKELY
EXCEED 80 DEG OVR MOST OF THE FA MON AND TUE. THE NEXT CHC OF ANY
SHWRS/TSTMS NO EARLIER THAN LATE TUE INTO TUE NGT AS PER THE 00Z
GFS...BUT IT MUST BE POINTED OUT THAT OTHER LONG RANGE MODELS LIKE
THE 00Z ECMWF COULD HOLD OFF RNFL EVEN LONGER...CONFIDENCE ON ANY
RNFL THIS LATE IN THE FCST...AS TYPICAL...IS LOW ATTM.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
NEAR TERM: MVFR WITH LOCAL IFR LIKELY THROUGH THIS MORNING DUE TO
LOW CLOUDS AND FOG. WHILE LOW CEILINGS WILL LINGER ACROSS THE
NORTH THROUGH MUCH OF THE DAY, EXPECT VFR CONDITIONS AT THE
SOUTHERN TAF SITES AS DRIER AIR WORKS INTO THE AREA. SHOWERS WITH
SCATTERED THUNDERSTORMS WILL AFFECT THE REGION THROUGH THIS
EVENING, ENDING FROM WEST TO EAST BY 02Z TONIGHT. SKIES WILL
BECOME PARTLY TO MOSTLY CLEAR THEREAFTER, WITH PERHAPS SOME LOCAL
IFR DUE TO FOG TOWARD DAYBREAK.
SHORT TO LONG TERM: VFR ANTICIPATED THU THRU SUN...XCPT PERHAPS
VERY BRIEF MVFR CONDITIONS POSSIBLE FRI AFTN ACROSS NRN TAF SITES
IN ISOLD HEAVIER SHWRS FRI AFTN.
&&
.MARINE...
NEAR TERM: DENSE FOG WILL KEEP VISIBILITY REDUCED TO BELOW 1 SM
ACROSS THE WATERS THROUGH EARLY THIS MORNING, BUT EXPECT
CONDITIONS TO IMPROVE BY THIS AFTERNOON. ISOLATED TO SCATTERED
SHOWERS ARE POSSIBLE THIS AFTERNOON, AND AN INCREASING SOUTH WIND
WILL ALLOW SEAS TO BUILD TO 3-4 FT. HOWEVER, EXPECT CONDITIONS TO
REMAIN BELOW SMALL CRAFT ADVISORY LEVELS, SO NO HEADLINES ARE
ANTICIPATED.
SHORT TO LONG TERM: NO HDLNS ANTICIPATED FOR THESE PDS THIS
UPDATE. WE BLENDED 00Z WW3 WITH SWAN NAM FOR WV HTS...SMOOTHED
ALG THE IMMEDIATE COAST TO BRING WV HTS DOWN TO ARND 1 FT. OVR
THE OUTER WATERS...WV HTS WILL RUN 2 TO 4 FT OR LESS.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HASTINGS
SHORT TERM...VJN
LONG TERM...VJN
AVIATION...HASTINGS/VJN
MARINE...HASTINGS/VJN
AREA FORECAST DISCUSSION
NWS GAYLORD MI
143 PM EDT WED AUG 14 2013
.SYNOPSIS...
ISSUED AT 327 AM EDT WED AUG 14 2013
HIGH PRESSURE IN SOUTH CENTRAL CANADA WILL MOVE TOWARD THE SOUTHERN
GREAT LAKES TONIGHT...THEN STALL OUT JUST TO OUR SOUTH AND EAST.
THIS WILL PROVIDE FOR AN EXTENDED PERIOD OF QUIET WEATHER...ALONG
WITH A GRADUAL WARMING TREND.
&&
.UPDATE...
ISSUED AT 127 PM EDT WED AUG 14 2013
IF THE 12Z GFS, NAM, AND RUC13 ARE RIGHT, THE 850 MB TEMPERATURES
ARE WARMING TO 6C BY NOW. THE 00Z ECMWF SAYS THAT AT THIS POINT
THE AREA OF 4C AIR OVER N LAKE MICHIGAN WOULD BE SMALLER. BASED ON
THE CURRENT VIS IMAGE, THINK THAT THE ECMWF HAS A BETTER HANDLE ON
IT. ALL OF THE MODELS HAVE A SIMILAR MOISTURE LOOK IN THE 850-700
MB LAYER AS THE CLOUDS STREAM OFF LAKES MICHIGAN AND SUPERIOR AND
TAKE A BIT OF TIME (ROUGHLY THE FIRST 10MILES OR SO) BEFORE THEY
GROW AND EXPAND. THIS TREND WILL CONTINUE FOR A FEW MORE HOURS AS
THE WARMER AIR BEGINS TO TAKE OVER. TEMPERATURES SEEM TO BE ON
TRACK WITH THE SFC WINDS 5 TO 10 KNOTS GUSTS TO 15KNOTS. SO WILL
LEAVE THE FORECAST AS IS.
UPDATE ISSUED AT 1053 AM EDT WED AUG 14 2013
850 MB TEMPERATURES ARE STILL AROUND +4C ON THE SOUNDING THIS
MORNING. SO WE WILL CONTINUE, AT LEAST THIS MORNING AND EARLY
AFTERNOON, WITH THE LAKE CU/SC CLOUDS. HOWEVER, THE LATEST NAM AND
RUC RUNS INSIST THAT BY 18Z THE 850 MB TEMPERATURES WILL BE AROUND
+6C OR +7C. THIS WOULD CERTAINLY CUT DOWN THE AMOUNT OF CLOUDS FOR
THE AFTERNOON AS THE DELTA T DIMINISHES. WILL KEEP THE GOING
FORECAST WITH PARTLY SUNNY AND HIGHS IN THE 60S.
UPDATE ISSUED AT 631 AM EDT WED AUG 14 2013
NO SIGNIFICANT UPDATES...BUT DID DECREASE CLOUD COVER TO CLEAR
ACROSS EASTERN UPPER...AND ONLY SOME PATCHY LAKE CLOUDS ACROSS NW
LOWER. ALSO SOME SHALLOW FOG IN LOW LYING AREAS. THIS WILL BURN
OFF QUICKLY...AND MOSTLY SUNNY SKIES WILL TURN TO DEVELOPING
STRATO CUMULUS...SIMILAR TO YESTERDAY...BUT NOT EXPECTED TO BE AS
WIDESPREAD.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 327 AM EDT WED AUG 14 2013
ITS JUST GOTTA GET BETTER RIGHT? AND INDEED...IT WILL. CULPRIT
BEHIND YESTERDAYS RIDICULOUSLY UNSEASONABLY COLD WEATHER STILL
PLAGUING THE REGION...WITH ANOMALOUSLY DEEP TROUGHING CENTERED OVER
THE EASTERN LAKES. COLD AIRMASS CENTERED RIGHT OVER THE HEART OF THE
NORTHERN LAKES...AS NOTED BY LOCAL 00Z SOUNDING WHICH HAD H8
TEMPERATURES OF ONLY 2C. WINDS AND POCKETS OF CLOUD COVER PREVENTING
SURFACE TEMPERATURES FROM DROPPING AS MUCH AS THEY COULD HAVE.
STILL...SIMPLY NOT YOUR TYPICAL MID AUGUST NIGHT WITH CURRENT
READINGS MOSTLY IN THE 40S. NOT ALL IS DOOM AND GLOOM... HOWEVER...
WITH MID LEVEL HEIGHTS ALREADY ON THE INCREASE AND SURFACE HIGH
PRESSURE BUILDING INTO THE REGION. THIS SIGNALS BETTER DAYS
AHEAD...KICKED OFF BY TODAY`S SLOW MODERATION AND INCREASING AMOUNTS
OF SUNSHINE (FANS OF SUMMER REALLY GOING TO LIKE THE EXTENDED
FORECAST...READ ABOUT THOSE GLORIOUS DETAILS IN THE LONG TERM
PORTION OF THE FORECAST). SIMPLY NOT MANY FORECAST CONCERNS HEADING
THROUGH TONIGHT...AND WHAT THERE ARE CENTER MAINLY ON CLOUD AND
TEMPERATURE TRENDS.
WHILE BY NO MEANS WARM...TODAY WILL FEEL A HECK OF A LOT BETTER THAN
TUESDAY. HIGH PRESSURE WILL CONTINUE TO BUILD INTO OUR AREA AS DEEP
UPPER TROUGHING SLIDES FURTHER OFF TO THE EAST. WEAK SHORTWAVE DOES
SLIDE SOUTHEAST ON BACKSIDE OF DEPARTING PARENT TROUGH...BUT IS
EXPECTED TO COME THROUGH WITH LITTLE FANFARE GIVEN DEARTH OF DEEP
MOISTURE. THERMAL PROFILES BEGIN TO MODERATE...AND INFLUX OF DRY AIR
SHOULD LEAD TO AT LEAST PARTIAL SUNSHINE. COOL AIR ALOFT LIKELY TO
LEAD TO ANOTHER ROUND OF DIURNALLY DRIVEN CLOUD COVER...ESPECIALLY
IN THE FAVORED AREAS OF NORTHEAST LOWER AND EASTERN UPPER MICHIGAN.
STRONG H7 CENTERED CAPPING AND DRY LOW LEVELS SHOULD PREVENT ANY
SHOWER ACTIVITY. CAN FIND NO COMPELLING REASON TO DEVIATE FROM
INHERITED CLOUD COVER FORECAST...FEATURING A MAINLY PARTLY CLOUDY
DAY...WITH MORE SUNSHINE CLOSER TO LAKE MICHIGAN. SIMPLE AIRMASS
MODIFICATION AND SUNSHINE WILL ALLOW TEMPERATURES TO MODERATE
SEVERAL DEGREES...WITH DAYTIME HIGHS MAKING A RUN INTO THE MIDDLE
AND UPPER 60S. STILL SEVERAL DEGREES BELOW NORMAL...BUT A DEFINITE
STEP IN THE RIGHT DIRECTION.
MAINLY CLEAR AND QUIET HEADING THROUGH TONIGHT AS HIGH PRESSURE
SETTLES ACROSS THE NORTHERN OHIO VALLEY. PLACEMENT OF CENTER OF HIGH
TO OUR SOUTH SHOULD KEEP TEMPERATURES FROM BECOMING TOO EXTREME.
STILL...ANOTHER CHILLY NIGHT...WITH INTERIOR LOWS MAINLY IN THE
40S...AND SHORELINE COMMUNITIES JUST A TOUCH WARMER.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 327 AM EDT WED AUG 14 2013
READY FOR A RETURN TO SUMMER? UPPER LEVEL PATTERN WILL MORPH FROM
EASTERN CONUS TROUGHING AND COOL WEATHER...TO RISING HEIGHTS IN A
ZONAL MORE SEASONABLE PATTERN. DOME OF WARM/HOT AIR AND PERSISTENT
RIDGING OVER THE ROCKIES WILL SLOWLY PEEL OVER INTO THE GREAT
LAKES...HELPING RETURN US TO MORE NORMAL SUMMERTIME WARMTH.
WEDNESDAY THROUGH FRIDAY...THE GREATEST HEIGHT RISES WILL OCCUR
OVER THIS TIME PERIOD...WHILE THE LOW LEVEL COOLER POOL OF AIR
REMAINS ENTRENCHED BACK ACROSS THE GREAT LAKES. EITHER WAY...THE
AIR MASS WILL BE RELATIVELY DRY...WITH WEAK SHORTWAVE ENERGY
DROPPING IN FROM SRN CANADA OUT OF WEAKENING NW FLOW ALOFT. MODELS
STILL ANTICIPATING A WEAK PIECE OF THIS ENERGY POSSIBLY CUTTING OFF
IN THE HEART OF THE COUNTRY AND LIFTING THROUGH THE SRN/EASTERN
GREAT LAKES. SUCH WEAK FLOW/ENERGY AND RELATIVELY DRY AIR FOR ANY
MENTION OF A CHANCE OF PRECIPITATION. WINDS WILL BE LIGHT WITH
AFTERNOON LAKE BREEZES CONSOLIDATING THE BETTER SCATTERED
AFTERNOON CUMULUS TO NE LOWER AND EASTERN UPPER AWAY FROM THE
LAKES. TEMPERATURES WILL WARM FROM THE MIDDLE 70S THURSDAY TO
AROUND 80F BY SATURDAY. BEAUTIFUL WEATHER.
SATURDAY THROUGH TUESDAY...HEIGHTS WILL HAVE RISEN AS MUCH AS THEY
ARE EXPECTED. WITH A WESTERLY LOW LEVEL FLOW ALREADY HAVE USHERED
IN MORE SEASONABLY WARM SUMMERTIME AIR. TEMPERATURES OVER THIS
TIME PERIOD WILL HAVE WARMED TO THE LOWER HALF OF THE 80S FOR MOST
LOCALES. CHANCES FOR SHOWERS AND A STORM ARE STILL QUITE
SMALL...BUT BETTER SHORTWAVE ENERGY AND EXPECTED TO DROP INTO THE
REGION MONDAY THROUGH TUESDAY. CONTINUED BEAUTIFUL WEATHER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 127 PM EDT WED AUG 14 2013
TVC, PLN, AND MBL SHOULD BE PREDOMINATELY SCT TO BKN VFR CIGS, AS
THEY ARE IN THAT TRANSITION ZONE WHERE THE CLOUDS ARE JUST GETTING
GOING. AS WE GET FURTHER INTO THE DAY, AS THE TEMPERATURES AT 850
MB WARM AND THE MOISTURE DIMINISHES, WILL EXPECT THAT THESE THREE
SITES WILL HAVE DIMINISHING CLOUDS. APN, WILL TAKE A LITTLE
LONGER, BUT ITS CIGS HAVE ALL BEEN IN THE VFR CATEGORY, AND
CURRENTLY THIS LOOKS LIKE IT WILL REMAIN THAT WAY INTO THE
EVENING, WHEN THE CLOUDS EVAPORATE THERE. WINDS WILL BECOME
VARIABLE OVERNIGHT AS THE HIGH ALLOWS THE SFC WINDS TO DECOUPLE.
THURSDAY LOOKS LIKE IT WILL BE A LESS CLOUDIER VERSION OF TODAY AS
THE WINDS REMAIN, BUT THE TEMPERATURES WILL BE WARMER SO THAT WE
DON`T GET DIURNAL/LAKE CLOUDS.
&&
.MARINE...
ISSUED AT 327 AM EDT WED AUG 14 2013
PRESSURE GRADIENT WILL GRADUALLY RELAX HEADING THROUGH
TODAY AND TONIGHT AS HIGH PRESSURE BUILDS SOUTHEAST TOWARDS THE
NORTHERN OHIO VALLEY. CURRENT NORTH TO NORTHWEST WINDS WILL
GRADUALLY BACK MORE WESTERLY TODAY...AND BECOME SOUTHWEST THROUGH
THE OVERNIGHT HOURS. WINDS WILL REMAIN A TOUCH GUSTY...ESPECIALLY UP
NEAR THE STRAITS AND ACROSS WHITEFISH BAY. WIND SPEEDS AND WAVES
SHOULD REMAIN BELOW SCA CRITERIA. ALL INHERITED ADVISORIES WILL BE
DROPPED WITH THIS FORECAST RELEASE.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...JL
SYNOPSIS...SD
SHORT TERM...MB
LONG TERM...SD
AVIATION...JL
MARINE...MB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
125 PM EDT WED AUG 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 509 AM EDT WED AUG 14 2013
DRY HIGH PRESSURE WILL CONTINUE TO BE THE MAIN STORY TODAY. NW WINDS
WILL BE THE RULE...KEEPING LOCATIONS NEAR LAKE SUPERIOR IN THE 60S
FOR HIGH TEMPS WHILE REACHING INTO THE LOWER 70S INLAND.
A THIN RIBBON OF CLOUDS ACROSS S ONTARIO AND N LAKE SUPERIOR WILL
CONTINUE TO SHIFT SSE AND EXPAND OVER LAKE SUPERIOR THIS
MORNING...AND PUSH OVER CENTRAL AND E UPPER MI THROUGH THE DAY
TODAY. THIS BAND HAS BEEN PICKED UP BY ONLY A FEW MODELS...NAMELY
THE RUC AND CANADIAN...AND TO A LESSER EXTENT THE NAM. WILL LEVERAGE
THEM MORE ON THE CLOUD FCST THROUGH THE DAY TODAY GIVEN THEIR BETTER
INITIAL PROGNOSIS.
ANOTHER MOSTLY CLEAR NIGHT IS IN STORE FOR US. HOWEVER...TEMPS
SHOULD BOTTOM OUT AROUND 5F WARMER THAN THIS MORNING. WILL KEEP ANY
MENTION OF FROST OUT OF THE FCST WITH THE LOWEST READINGS EXPECTED
AT THIS TIME BEING RIGHT AROUND 40F INLAND FROM THE GREAT LAKES.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 451 AM EDT WED AUG 14 2013
THU AND THU NIGHT...NW MID/UPPER LEVEL FLOW THROUGH THE NRN GREAT LAKES
WILL PREVAIL BETWEEN A TROUGH OVER QUEBEC AND A RIDGE FROM THE SW
CONUS INTO CNTRL CANADA. WITH THE DRY AIRMASS REMAINING OVER THE
REGION...ANY WEAK SHORTWAVES WILL NOT PRODUCE ANY PCPN. INCEASING
WAA AS THE SFC HIGH SHIFTS TOWARD THE SRN GREAT LAKES WILL PUSH 850
MB TEMPS INTO THE 10C-12C ALLOWING HIGHS TO CLIMB BACK INTO THE MID
AND UPPER 70S. WITH MOSTLY CLEAR SKIES AND LIGHT WINDS...TEMPS WILL
DROP BACK TO AROUND 50.
FRI...ALTHOUGH LOW LEVEL MOISTURE TRANSPORT BACK INTO THE REGION
WILL BE MODEST...EXPECT ENOUGH OF AN INCREASE FOR DEWPOINTS TO CLIMB
INTO THE LOWER TO MID 50S. THE NAM/GFS/UKMET SUGGEST THAT SOME PCPN
MAY BE POSSIBLE...ESPECIALY DURING PEAK HEATING WITH MLCAPE VALUES
CLIMBING INTO THE 400-800 J/KG RANGE. HOWEVER...THE MODELS MAY ALSO
BE TOO AGGRESSIVE WITH THE AMOUNT OF MOISTURE AVAILABLE MAKING THE
INVERSION/CAPPING AROUND 700 MB MORE DIFFICULT TO OVERCOME.
SO...ONLY ADDED SLIGHT CHANCE WORDING FOR SHRA/TSRA FOR INLAND WEST
LOCATIONS WITH POPS REMAINING AOB 20 PCT.
SAT...THE MID LEVEL RIDGE WILL BUILD INTO THE AREA...BOOSTING THE
CAPPING AND REDUCING ANY PCPN CHANCES EVEN THOUGH LOW LEVEL MOISTURE
WILL ALSO INCREASE. TEMPERATURES WILL REMAIN ABOVE AVERAGE WITH
HIGHS INTH THE UPPER 70S.
SUN-TUE...THE GFS/GEM/UKMET SUGGEST THAT A SHORTWAVE TROUGH MAY MOVE
INTO THE NRN GREAT LAKES MON INTO MON NIGHT BRINGING SHRA/TSRA POTENTIAL
WHILE THE ECMWF WIH A MORE ZONAL PATTERN KEEPS A WEAKER SHRTWV
FARTHERN N THROUGH NRN ONTARIO. GIVEN MODEL DIFFERENCES...FCST
REMAINS IN LIE WITH MDLS CONSENSUS SLIGHT CHANCE POPS. TEMPERATURES
WILL REMAIN ABOVE NORMAL WITH HIGHS FROM THE UPPER 70S TO THE LOWER
80S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 125 PM EDT WED AUG 14 2013
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD...AS A HIGH PRESSURE
RIDGE REMAINS OVER THE AREA. EXPECT THE DIURNAL CU TO DIMINISH
TOWARDS EVENING AND A MAINLY CLEAR SKY OVERNIGHT. SOME DIURNAL CU
IS AGAIN EXPECTED TOMORROW AFTERNOON AT KIWD/KSAW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 400 AM EDT WED AUG 14 2013
A RIDGE OF HIGH PRESSURE SHOULD BE THE RULE THROUGH THE UPCOMING
WEEKEND...RESULTING IN RELATIVLY LIGHT WINDS. LARGE HIGH PRESSURE
STRETCHING FROM SOUTH CENTRAL CANADA THROUGH THE UPPER GREAT LAKES
AND MID MISSISSIPPI VALLEY WILL SLOWLY SINK ACROSS THE OHIO VALLEY
AND MID ATLANTIC STATES ON THURSDAY. THE EVER-PRESENT AREA OF HIGH
PRESSURE WILL THEN EXPAND NORTHWARD TO THE LOWER GREAT LAKES AND NEW
ENGLAND STATES ON THURSDAY NIGHT THROUGH SUNDAY. EXPECT A TROUGH TO
SET UP OVER THE NORTHERN PLAINS INTO MANITOBA ON SUNDAY...WITH WIND
GUSTS STILL AROUND 20KTS OR LESS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KF
LONG TERM...JLB
AVIATION...SRF
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
525 AM EDT WED AUG 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 509 AM EDT WED AUG 14 2013
DRY HIGH PRESSURE WILL CONTINUE TO BE THE MAIN STORY TODAY. NW WINDS
WILL BE THE RULE...KEEPING LOCATIONS NEAR LAKE SUPERIOR IN THE 60S
FOR HIGH TEMPS WHILE REACHING INTO THE LOWER 70S INLAND.
A THIN RIBBON OF CLOUDS ACROSS S ONTARIO AND N LAKE SUPERIOR WILL
CONTINUE TO SHIFT SSE AND EXPAND OVER LAKE SUPERIOR THIS
MORNING...AND PUSH OVER CENTRAL AND E UPPER MI THROUGH THE DAY
TODAY. THIS BAND HAS BEEN PICKED UP BY ONLY A FEW MODELS...NAMELY
THE RUC AND CANADIAN...AND TO A LESSER EXTENT THE NAM. WILL LEVERAGE
THEM MORE ON THE CLOUD FCST THROUGH THE DAY TODAY GIVEN THEIR BETTER
INITIAL PROGNOSIS.
ANOTHER MOSTLY CLEAR NIGHT IS IN STORE FOR US. HOWEVER...TEMPS
SHOULD BOTTOM OUT AROUND 5F WARMER THAN THIS MORNING. WILL KEEP ANY
MENTION OF FROST OUT OF THE FCST WITH THE LOWEST READINGS EXPECTED
AT THIS TIME BEING RIGHT AROUND 40F INLAND FROM THE GREAT LAKES.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 451 AM EDT WED AUG 14 2013
THU AND THU NIGHT...NW MID/UPPER LEVEL FLOW THROUGH THE NRN GREAT LAKES
WILL PREVAIL BETWEEN A TROUGH OVER QUEBEC AND A RIDGE FROM THE SW
CONUS INTO CNTRL CANADA. WITH THE DRY AIRMASS REMAINING OVER THE
REGION...ANY WEAK SHORTWAVES WILL NOT PRODUCE ANY PCPN. INCEASING
WAA AS THE SFC HIGH SHIFTS TOWARD THE SRN GREAT LAKES WILL PUSH 850
MB TEMPS INTO THE 10C-12C ALLOWING HIGHS TO CLIMB BACK INTO THE MID
AND UPPER 70S. WITH MOSTLY CLEAR SKIES AND LIGHT WINDS...TEMPS WILL
DROP BACK TO AROUND 50.
FRI...ALTHOUGH LOW LEVEL MOISTURE TRANSPORT BACK INTO THE REGION
WILL BE MODEST...EXPECT ENOUGH OF AN INCREASE FOR DEWPOINTS TO CLIMB
INTO THE LOWER TO MID 50S. THE NAM/GFS/UKMET SUGGEST THAT SOME PCPN
MAY BE POSSIBLE...ESPECIALY DURING PEAK HEATING WITH MLCAPE VALUES
CLIMBING INTO THE 400-800 J/KG RANGE. HOWEVER...THE MODELS MAY ALSO
BE TOO AGGRESSIVE WITH THE AMOUNT OF MOISTURE AVAILABLE MAKING THE
INVERSION/CAPPING AROUND 700 MB MORE DIFFICULT TO OVERCOME.
SO...ONLY ADDED SLIGHT CHANCE WORDING FOR SHRA/TSRA FOR INLAND WEST
LOCATIONS WITH POPS REMAINING AOB 20 PCT.
SAT...THE MID LEVEL RIDGE WILL BUILD INTO THE AREA...BOOSTING THE
CAPPING AND REDUCING ANY PCPN CHANCES EVEN THOUGH LOW LEVEL MOISTURE
WILL ALSO INCREASE. TEMPERATURES WILL REMAIN ABOVE AVERAGE WITH
HIGHS INTH THE UPPER 70S.
SUN-TUE...THE GFS/GEM/UKMET SUGGEST THAT A SHORTWAVE TROUGH MAY MOVE
INTO THE NRN GREAT LAKES MON INTO MON NIGHT BRINGING SHRA/TSRA POTENTIAL
WHILE THE ECMWF WIH A MORE ZONAL PATTERN KEEPS A WEAKER SHRTWV
FARTHERN N THROUGH NRN ONTARIO. GIVEN MODEL DIFFERENCES...FCST
REMAINS IN LIE WITH MDLS CONSENSUS SLIGHT CHANCE POPS. TEMPERATURES
WILL REMAIN ABOVE NORMAL WITH HIGHS FROM THE UPPER 70S TO THE LOWER
80S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 524 AM EDT WED AUG 14 2013
WHILE A FEW CLOUDS WILL PASS FROM TIME TO TIME...THEY SHOULD REMAIN
VFR...WITH DIURNAL WINDS NEARING 10KTS DURING THE DAYTIME HOURS
TODAY.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 400 AM EDT WED AUG 14 2013
A RIDGE OF HIGH PRESSURE SHOULD BE THE RULE THROUGH THE UPCOMING
WEEKEND...RESULTING IN RELATIVLY LIGHT WINDS. LARGE HIGH PRESSURE
STRETCHING FROM SOUTH CENTRAL CANADA THROUGH THE UPPER GREAT LAKES
AND MID MISSISSIPPI VALLEY WILL SLOWLY SINK ACROSS THE OHIO VALLEY
AND MID ATLANTIC STATES ON THURSDAY. THE EVER-PRESENT AREA OF HIGH
PRESSURE WILL THEN EXPAND NORTHWARD TO THE LOWER GREAT LAKES AND NEW
ENGLAND STATES ON THURSDAY NIGHT THROUGH SUNDAY. EXPECT A TROUGH TO
SET UP OVER THE NORTHERN PLAINS INTO MANITOBA ON SUNDAY...WITH WIND
GUSTS STILL AROUND 20KTS OR LESS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KF
LONG TERM...JLB
AVIATION...KF
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
510 AM EDT WED AUG 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 509 AM EDT WED AUG 14 2013
DRY HIGH PRESSURE WILL CONTINUE TO BE THE MAIN STORY TODAY. NW WINDS
WILL BE THE RULE...KEEPING LOCATIONS NEAR LAKE SUPERIOR IN THE 60S
FOR HIGH TEMPS WHILE REACHING INTO THE LOWER 70S INLAND.
A THIN RIBBON OF CLOUDS ACROSS S ONTARIO AND N LAKE SUPERIOR WILL
CONTINUE TO SHIFT SSE AND EXPAND OVER LAKE SUPERIOR THIS
MORNING...AND PUSH OVER CENTRAL AND E UPPER MI THROUGH THE DAY
TODAY. THIS BAND HAS BEEN PICKED UP BY ONLY A FEW MODELS...NAMELY
THE RUC AND CANADIAN...AND TO A LESSER EXTENT THE NAM. WILL LEVERAGE
THEM MORE ON THE CLOUD FCST THROUGH THE DAY TODAY GIVEN THEIR BETTER
INITIAL PROGNOSIS.
ANOTHER MOSTLY CLEAR NIGHT IS IN STORE FOR US. HOWEVER...TEMPS
SHOULD BOTTOM OUT AROUND 5F WARMER THAN THIS MORNING. WILL KEEP ANY
MENTION OF FROST OUT OF THE FCST WITH THE LOWEST READINGS EXPECTED
AT THIS TIME BEING RIGHT AROUND 40F INLAND FROM THE GREAT LAKES.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 451 AM EDT WED AUG 14 2013
THU AND THU NIGHT...NW MID/UPPER LEVEL FLOW THROUGH THE NRN GREAT LAKES
WILL PREVAIL BETWEEN A TROUGH OVER QUEBEC AND A RIDGE FROM THE SW
CONUS INTO CNTRL CANADA. WITH THE DRY AIRMASS REMAINING OVER THE
REGION...ANY WEAK SHORTWAVES WILL NOT PRODUCE ANY PCPN. INCEASING
WAA AS THE SFC HIGH SHIFTS TOWARD THE SRN GREAT LAKES WILL PUSH 850
MB TEMPS INTO THE 10C-12C ALLOWING HIGHS TO CLIMB BACK INTO THE MID
AND UPPER 70S. WITH MOSTLY CLEAR SKIES AND LIGHT WINDS...TEMPS WILL
DROP BACK TO AROUND 50.
FRI...ALTHOUGH LOW LEVEL MOISTURE TRANSPORT BACK INTO THE REGION
WILL BE MODEST...EXPECT ENOUGH OF AN INCREASE FOR DEWPOINTS TO CLIMB
INTO THE LOWER TO MID 50S. THE NAM/GFS/UKMET SUGGEST THAT SOME PCPN
MAY BE POSSIBLE...ESPECIALY DURING PEAK HEATING WITH MLCAPE VALUES
CLIMBING INTO THE 400-800 J/KG RANGE. HOWEVER...THE MODELS MAY ALSO
BE TOO AGGRESSIVE WITH THE AMOUNT OF MOISTURE AVAILABLE MAKING THE
INVERSION/CAPPING AROUND 700 MB MORE DIFFICULT TO OVERCOME.
SO...ONLY ADDED SLIGHT CHANCE WORDING FOR SHRA/TSRA FOR INLAND WEST
LOCATIONS WITH POPS REMAINING AOB 20 PCT.
SAT...THE MID LEVEL RIDGE WILL BUILD INTO THE AREA...BOOSTING THE
CAPPING AND REDUCING ANY PCPN CHANCES EVEN THOUGH LOW LEVEL MOISTURE
WILL ALSO INCREASE. TEMPERATURES WILL REMAIN ABOVE AVERAGE WITH
HIGHS INTH THE UPPER 70S.
SUN-TUE...THE GFS/GEM/UKMET SUGGEST THAT A SHORTWAVE TROUGH MAY MOVE
INTO THE NRN GREAT LAKES MON INTO MON NIGHT BRINGING SHRA/TSRA POTENTIAL
WHILE THE ECMWF WIH A MORE ZONAL PATTERN KEEPS A WEAKER SHRTWV
FARTHERN N THROUGH NRN ONTARIO. GIVEN MODEL DIFFERENCES...FCST
REMAINS IN LIE WITH MDLS CONSENSUS SLIGHT CHANCE POPS. TEMPERATURES
WILL REMAIN ABOVE NORMAL WITH HIGHS FROM THE UPPER 70S TO THE LOWER
80S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1206 AM EDT WED AUG 14 2013
VFR CONDITIONS WILL CONTINUE THROUGH THE PERIOD AT CMX AND SAW. AT
IWD SOME BR IS BRINGING VIS DOWN...WHICH SHOULD LAST INTO THE REST
OF TONIGHT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 400 AM EDT WED AUG 14 2013
A RIDGE OF HIGH PRESSURE SHOULD BE THE RULE THROUGH THE UPCOMING
WEEKEND...RESULTING IN RELATIVLY LIGHT WINDS. LARGE HIGH PRESSURE
STRETCHING FROM SOUTH CENTRAL CANADA THROUGH THE UPPER GREAT LAKES
AND MID MISSISSIPPI VALLEY WILL SLOWLY SINK ACROSS THE OHIO VALLEY
AND MID ATLANTIC STATES ON THURSDAY. THE EVER-PRESENT AREA OF HIGH
PRESSURE WILL THEN EXPAND NORTHWARD TO THE LOWER GREAT LAKES AND NEW
ENGLAND STATES ON THURSDAY NIGHT THROUGH SUNDAY. EXPECT A TROUGH TO
SET UP OVER THE NORTHERN PLAINS INTO MANITOBA ON SUNDAY...WITH WIND
GUSTS STILL AROUND 20KTS OR LESS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KF
LONG TERM...JLB
AVIATION...TITUS
MARINE...KF
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
324 AM EDT WED AUG 14 2013
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/HYDRO/MARINE
.SYNOPSIS...
ISSUED AT 324 AM EDT WED AUG 14 2013
TODAY WILL BE THE COLDEST DAY FOR AT LEAST THE NEXT WEEK OR TWO.
DESPITE SUNSHINE TEMPERATURES WILL CLIMB TO AROUND 70. A WARM UP
WILL BEGIN THURSDAY AS TEMPERATURES CLIMB THROUGH THE 70S AND INTO
THE 80S BY THE WEEKEND. DRY WEATHER IS EXPECTED THROUGH THE WEEKEND.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 324 AM EDT WED AUG 14 2013
FORECAST CONCERNS ARE MINIMAL THIS MORNING.
HIGH PRESSURE AT THE SFC COUPLED WITH TROUGHING ALOFT WILL LIKELY
CREATE SEVERAL DAYS OF DIURNALLY DRIVEN CU FOLLOWED BY MOSTLY CLEAR
SKIES THROUGH FRIDAY.
SFC ANALYSIS SHOWS HIGH PRESSURE OVER WISCONSIN. THIS HIGH WILL
CONTINUE TO MOVE TOWARD LOWER MICHIGAN DURING THE NEXT FEW DAYS.
LATEST IR LOOP SHOWS THE LAST OF THE STRATOCU COVERING THE THUMB AND
CLEAR SKIES OVER THE CWA.
WE SHOULD SEE PARTLY CLOUDY SKIES TODAY WITH QUITE A BIT OF SUNSHINE
THIS MORNING AND CU THIS AFTERNOON GIVEN THE COOLER TEMPS ALOFT
ASSOCIATED WITH THE UPPER TROUGH. AS THE DEEP UPPER TROUGH MOVES
NEWD THE CORE OF THE COLD AIR ALOFT WILL GO WITH IT AND TEMPS WILL
BEGIN TO RISE. LOOK FOR A WARMING TREND THROUGH FRIDAY AS HIGHS
REBOUND TO THE MID 70S...WHICH WILL STILL BE A FEW DEGREES BELOW
NORMAL. GIVEN THE DRY AIRMASS...RAIN IS NOT EXPECTED.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 324 AM EDT WED AUG 14 2013
OVERALL THE TREND OF THE MODELS SUPPORTS WARMER TEMPERATURES FOR THE
EARLY TO MIDDLE PART OF NEXT WEEK. I BUMPED UP TEMPERATURES A FEW
DEGREES AS A RESULT. WITH THE HIGH PRESSURE SYSTEM TRACKING
SOUTHWARD FROM NEW ENGLAND DOWN TO THE CAROLINAS SUNDAY INTO
TUESDAY...THIS SUPPORTS A PERIOD OF WARM AIR ADVECTION FOR THE GREAT
LAKES REGION. TEMPS AT 850 MB RISE INTO THE TEENS. THIS SHOULD
SUPPORT DAYTIME SURFACE TEMPS INTO THE 80S.
AS FOR PRECIPITATION...THIS RELATIVELY WESTWARD SETUP OF THE HIGH
PRESSURE SYSTEM...AS OPPOSED TO A BERMUDA HIGH...MEANS THE MAIN AXIS
OF GULF MOISTURE ADVECTS NORTHWARD THROUGH THE WESTERN PLAINS. SO
IT APPEARS THAT THE ARRIVAL OF THIS DEEPER MOISTURE INTO THE GREAT
LAKES REGION...WILL BE DELAYED UNTIL MAYBE THE THE MIDDLE OF NEXT
WEEK. AS A RESULT I KEPT POPS LOW FOR THIS FORECAST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1205 AM EDT WED AUG 14 2013
CLEAR SKIES AND LIGHT NORTH TO NORTHWEST WINDS ARE EXPECTED DURING
THE EARLY MORNING HOURS OF WEDNESDAY AS A LARGE CANADIAN ORIGIN
HIGH MOVES ACROSS LOWER MICHIGAN. THE HRRR DID A VERY GOOD JOB
THIS EVENING OF SHOWING THE CLOUDS DISSIPATING IN THE 01-03Z TIME
FRAME. THE COLD AIR STRATOCUMULUS CLOUDS SHOULD STAY OVER LAKE
HURON. WEDNESDAY SHOULD BE A SUNNY DAY BUT MODEL SOUNDING SUGGEST
SOME HIGH BASED CU DURING THE LATE MORNING AND EARLY AFTERNOON.
&&
.MARINE...
ISSUED AT 324 AM EDT WED AUG 14 2013
BOTH THE BHS AND SCA HAVE EXPIRED. WIND SPEEDS AND WAVE HEIGHTS WILL
CONTINUE TO DECREASE TODAY. INITIALLY THOUGH THIS MORNING THERE
COULD BE SOME WAVE HEIGHTS AROUND 3 FEET BEFORE THEY DECREASE LATER
IN THE DAY.
&&
.HYDROLOGY...
ISSUED AT 324 AM EDT WED AUG 14 2013
NO HYDRO CONCERNS. RIVER LEVELS WILL SLOWLY FALL THROUGH THE WEEKEND
WITH NO RAIN EXPECTED.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...93
SHORT TERM...93
LONG TERM...MJS
AVIATION...WDM
HYDROLOGY...93
MARINE...93
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1205 AM EDT WED AUG 14 2013
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 306 PM EDT TUE AUG 13 2013
A WAVE OF LOW PRESSURE MOVING THROUGH THE AREA THIS AFTERNOON WILL
MOVE EAST OF THE AREA THIS EVENING. CLOUDS WILL GRADUALLY DIMINISH
THIS EVENING. HIGH PRESSURE WILL THEN BUILD INTO THE AREA BEGINNING
ON WEDNESDAY AND LASTING INTO THE WEEKEND. THIS WILL BRING DRY
WEATHER TO THE AREA. TEMPERATURES WILL START OUT COOL AND GRADUALLY
WARM THROUGH THE PERIOD.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 306 PM EDT TUE AUG 13 2013
THE ONLY WEATHER OF NOTE IN THE SHORT TERM IS FROM THIS AFTERNOON
INTO EARLY THIS EVENING WHEN THERE IS A CHANCE OF SPRINKLES UP NORTH
OR CHANCE OF A LIGHT SHOWER ALONG THE LAKESHORE. OTHER THAN
THAT...DRY AND COOL WEATHER CAN BE EXPECTED THROUGH THE REMAINDER OF
THE SHORT TERM.
THE GOING FORECAST IS ON TRACK THIS AFTERNOON WITH VERY LITTLE IF
ANY PCPN CURRENTLY BEING REPORTED. KGRR RADAR IN CLEAR AIR MODE IS
PICKING UP ON THE FLAT CU/STRATOCU PRESENT THIS AFTERNOON. NO RAIN
HAS BEEN REPORTED AT ANY STATION IN THE CWFA THUS FAR. THE SHORT
WAVE IS NOW ENTERING THE NRN SECTION OF THE CWFA...SO THIS WOULD BE
THE BEST CHC RIGHT NOW. FCST SOUNDINGS CONTINUE TO INDICATE AN
INVERSION AROUND 700 MB THAT IS PREVENTING SUFFICIENT VERTICAL
GROWTH OF THE CU FIELD. DRY AIR AT THE SFC ALSO IS LIMITING THE
GROWTH.
THE MID LEVEL TEMPERATURES WILL SLOWLY MODIFY THIS EVENING AS THE
SHORT WAVE MOVES EAST. WE WILL LOSE THE DIURNAL COMPONENT ALSO WHICH
WILL ONLY STRENGTHEN THE CAUSE FOR DRY CONDITIONS. OVER LAKE
INSTABILITY WILL REMAIN IN THE LOW TO MID TEENS...BUT THE 700 MB
INVERSION WILL EVEN LIMIT LAKE MODIFIED PARCELS. THIS WILL ALSO SHUT
DOWN THE LOW CHC OF WATERSPOUTS OVER THE LAKE. WINDS WILL DROP OFF
AND THEN TEMPS WILL RESPOND WITH THE DRY AIR IN PLACE. MOST
LOCATIONS SHOULD DROP DOWN INTO THE 40S...WITH NEAR 40 UP NORTH.
THE REMAINDER OF THE SHORT TERM FROM WED THROUGH THU NIGHT WILL THEN
REMAIN QUIET. THE LONG WAVE TROUGH WILL REMAIN ENTRENCHED OVER THE
AREA. THE UPPER JET WILL LIFT NORTHEAST PUTTING THE AREA UNDER THE
ANTI-CYCLONIC SIDE OF THE JET. HIGH PRESSURE AT THE SFC WILL THEN
RULE. H850 TEMPS WILL SLOWLY MODIFY FROM THE SINGLE DIGITS C
WED...TO THE LOWER TEENS BY THU NIGHT. THIS WILL ALLOW SFC TEMPS TO
MODIFY EACH DAY WITH A GOOD DEAL OF SUNSHINE. NIGHT TIME LOWS WILL
SLOWLY MODIFY ALSO. LIMITED DIURNAL CU IS EXPECTED.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 306 PM EDT TUE AUG 13 2013
WE WILL STILL BE UNDER THE REGIME OF COOL AIR ALOFT WITH THE
NORTHWEST FLOW THROUGH FRIDAY. THIS WILL CONTINUE TO PRODUCE
DIURNAL CU AND A POSSIBLE ISOLATED DAYTIME SHOWER ACROSS THE
NORTHERN CWA. HOWEVER THE NORTHWEST FLOW BECOMES MORE ZONAL AND
GRADUAL WARMING ALOFT AND AT THE SURFACE IS EXPECTED INTO THE
WEEKEND...MAKING FOR SUNNIER DAYS. UPPER RIDGING BEGINS TO MOVE
OVER THE REGION BY SUNDAY WHEN WE SHOULD FINALLY SEE NEAR TO
SLIGHTLY ABOVE NORMAL TEMPS.
MUCH OF THE LONG TERM PERIOD LOOKS DRY...ALTHOUGH THERE IS A TREND
TO BREAK DOWN THE RIDGE INTO THE MIDDLE OF NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1205 AM EDT WED AUG 14 2013
CLEAR SKIES AND LIGHT NORTH TO NORTHWEST WINDS ARE EXPECTED DURING
THE EARLY MORNING HOURS OF WEDNESDAY AS A LARGE CANADIAN ORIGAIN
HIGH MOVES ACROSS LOWER MICHIGAN. THE HRRR DID A VERY GOOD JOB
THIS EVENING OF SHOWING THE CLOUDS DISSIPATING IN THE 01-03Z TIME
FRAME. THE COLD AIR STRATOCUMULUS CLOUDS SHOULD STAY OVER LAKE
HURON. WEDNESDAY SHOULD BE A SUNNY DAY BUT MODEL SOUNDING SUGGEST
SOME HIGH BASED CU DURING THE LATE MORNING AND EARLY AFTERNOON.
&&
.MARINE...
ISSUED AT 306 PM EDT TUE AUG 13 2013
WE WILL BE LEAVING THE MARINE HEADLINES UP AS THE WINDS CONTINUE TO
BE RATHER BREEZY. THE BUOYS ARE SHOWING ELEVATED WAVES...HOWEVER THE
HIGHEST WAVES ARE LIKELY MORE OFFSHORE PER THE FLOW AND MID LAKE
BUOY. THE WINDS AND WAVES WILL COME DOWN TONIGHT. WATERSPOUT CHANCES
WILL DIMINISH ENOUGH THIS EVENING TO KEEP THE MENTION OUT AFTER THIS
AFTERNOON.
AFTER TONIGHT...NO SIGNIFICANT WINDS OR WAVES ARE THEN EXPECTED
THROUGH THE NEXT WEEK WITH A RELATIVELY WEAK GRADIENT EXPECTED TO BE
IN PLACE.
&&
.HYDROLOGY...
ISSUED AT 306 PM EDT TUE AUG 13 2013
NO HYDROLOGY ISSUES ARE EXPECTED THROUGH AT LEAST THE NEXT WEEK.
RIVERS AND STREAMS ARE RUNNING A BIT HIGH ACROSS THE SRN TWO ROWS OF
COUNTIES FROM THE HEAVIER RAINFALL THAT FELL YESTERDAY. THE LEVELS
HAVE PRETTY MUCH STABILIZED AND THE STREAMS ARE NOW COMING DOWN.
VERY LITTLE IF ANY ADDITIONAL RAINFALL OVER THE NEXT WEEK WILL ALLOW
LEVELS TO RECOVER BACK CLOSER TO NORMAL DOWN SOUTH...AND REMAIN
BELOW NORMAL UP NORTH WHERE VERY LITTLE RAINFALL HAS FALLEN RECENTLY.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 5 AM EDT EARLY THIS MORNING FOR
LMZ844>849.
&&
$$
SYNOPSIS...NJJ
SHORT TERM...NJJ
LONG TERM...JK
AVIATION...WDM
HYDROLOGY...NJJ
MARINE...NJJ
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1028 PM CDT THU AUG 15 2013
.UPDATE...
UPDATE FOR 06Z AVIATION DISCUSSION BELOW
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 339 PM CDT THU AUG 15 2013
MAIN FORECAST CHALLENGE IN THE SHORT TERM IS CLOUD COVER AND THE
POSSIBILITY OF ANY LIGHT SHRA/SPRINKLES THROUGH EARLY THIS EVENING.
OTHERWISE... QUIET WEATHER WILL CONTINUE TO BE THE THEME THROUGH
FRIDAY AS WE CONTINUE TO SLOWLY WARM WITH THE BUILDING UPPER RIDGE.
LATEST WATER VAPOR IMAGERY AND RAP UPPER AIR ANALYSES SHOWS THE ALL
TOO FAMILIAR PATTERN OF THE UPPER RIDGE TO OUR WEST AND UPPER TROUGH
TO OUR EAST. HOWEVER... FINALLY STARTING TO SEE SOME CHANGE IN
THIS... WHICH WILL GET FURTHER ACCELERATED NEXT WEEK AS RIDGE
BROADENS AND FLATTENS OVER THE CONUS AND EXERTS ITS MAIN PROMINENCE
OVER THE CENTER PART OF THE COUNTRY. IN THE MEANTIME... WE COULD SEE
SOME SHRA AND/OR SPRINKLES THROUGH EARLY THIS EVENING AS SOME
LINGERING LOW LEVEL INSTABILITY HELPS PRODUCE SOME TCU WITH PERHAPS
SOME PCPN MANAGING TO FALL OUT OF IT. WE WILL BEGIN TO GET INTO
RETURN FLOW ON FRIDAY AS THE SURFACE HIGH MOVES INTO THE EASTERN
GREAT LAKES... BUT ANY MEANINGFUL WARM ADVECTION WILL WAIT UNTIL
BEYOND THAT POINT. FRIDAY SHOULD BE SIMILAR... BUT SLIGHTLY
WARMER... THAN TODAY WITHOUT ANY SHRA/SPRINKLE CHANCE AS WARMER AIR
ALOFT AND ASSOCIATED SUBSIDENCE WORK INTO THE AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 339 PM CDT THU AUG 15 2013
MORE SUMMERLIKE PATTERN TAKES HOLD LATE IN THE WEEKEND AND LINGERS
THROUGHOUT THE WEEK. THE UPPER RIDGE OVER THE PLAINS CONTINUES TO
GRADUALLY EXPAND EASTWARD FRIDAY NIGHT THROUGH THE UPCOMING
WEEKEND. A DRY AND WARMING PATTERN IS EXPECTED OVER THE NEXT SEVEN
DAYS. SOME OF THE GUIDANCE DOES MANAGE TO GENERATE LIGHT
PRECIPITATION NEAR THEN MN/SD BORDER OVER THE WEEKEND ALONG A DIFFUSE
MID LEVEL BOUNDARY. THE MOISTURE MIGHT BE A BIT OVERDONE SO WILL
CONTINUE TO LEAVE DRY MENTION. BY SUNDAY...HIGHS WILL BE ABOVE
CLIMATE NORMALS WITH TEMPS IN THE 80S. AS MENTIONED IN OUR
DISCUSSION YESTERDAY...THE CENTRAL ATLANTIC RIDGE IS EXPECTED TO
DRIFT SOUTHWEST WITH TIME. THE ENSM FORECAST SUPPORTS THIS WITH
KEEPING POSITIVE HEIGHT ANOMALIES FARTHER SOUTH THROUGH THE END OF
THE MONTH. THIS DISPLACEMENT OF THE ATLANTIC RIDGE WILL ALLOW THE
PERSISTENT EAST COAST TROUGH /OUR LOCAL NORTHWEST FLOW/ A CHANCE
TO SHIFT EAST. THE MODELS COMING INTO MUCH BETTER AGREEMENT IN THE
EXTENDED. WHILE THE RIDGE DOES BECOME FLATTER EARLY NEXT WEEK AS A
SERIES OF SHORTWAVES TRACK JUST NORTH OF THE CANADIAN BORDER. A
BOUNDARY APPROACHES THE REGION ON MONDAY...BUT ALL MODELS DISSOLVE
THIS FEATURE NORTHWEST OF THE FORECAST AREA. THE OPERATIONAL GFS
AND TO SOME DEGREE THE ECMWF SHOW THE A GLIMPSE OF THE WARMING
TREND THIS WEEKEND WITH 80S...BUT THE WARM UP BEGINS IN EARNEST
EARLY NEXT WEEK. 850 MB TEMPS GET BACK UP INTO THE UPPER TEENS AND
LOWER 20S. GIVEN THE DRY ANTECEDENT CONDITIONS AND EXPECTED
BUILDING RIDGE...MID TO UPPER 80S SEEM EASILY OBTAINABLE NEXT
WEEK...AND WE SHOULD ONCE AGAIN SEE 90 DEGREES FOR THE FIRST TIME
IN OVER A MONTH. MIXING TO 850-750 MB WITH A SLIGHT SUPER
ADIABATIC LAYER GIVES NEAR RECORD TEMPS OF 95-99 DEGREES. SO...WE
WILL NEED TO MONITOR THE TEMP ADVECTION AND MIXING POTENTIAL.
CLOUD COVER ASIDE...THIS HAS A CHANCE TO BE A HOT STRETCH.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 1030 PM CDT THU AUG 15 2013
PATCHY FOG DEVELOPMENT IS POSSIBLE OVERNIGHT...OTHERWISE VFR
CONDITIONS ARE EXPECTED THROUGH THE PERIOD. HAVE INCLUDED
TEMPORARY MVFR VSBYS RESTRICTIONS AT KRWF AND KRNH. FEW-SCT
CUMULUS CLOUDS ARE EXPECTED ON FRIDAY...WITH A FEW CIRRUS ON
FRIDAY NIGHT. LIGHT AND VARIABLE WINDS OVERNIGHT BECOME SSW AND
INCREASE TO SPEEDS OF 5-10 KTS.
KMSP...
FEW-SCT CLOUDS FROM 5-8KFT THROUGH FRIDAY AFTERNOON...WITH A FEW
CIRRUS INTO FRIDAY EVENING. SSW WINDS AOB 5 KTS
OVERNIGHT...INCREASE TO AROUND 8 KTS FRIDAY AFTERNOON...THEN
DECREASE BACK BELOW 5 KTS BY SUNSET FRIDAY EVE.
/OUTLOOK FOR KMSP/
SAT...VFR. WINDS S 10-15 KTS.
SUN...VFR. WINDS SSW 10-15 KTS.
MON...VFR. WINDS SW 10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...CLF
LONG TERM...TRH
AVIATION...LS
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
726 PM CDT THU AUG 15 2013
.UPDATE...
FOR 00Z AVIATION DISCUSSION BELOW
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 339 PM CDT THU AUG 15 2013
MAIN FORECAST CHALLENGE IN THE SHORT TERM IS CLOUD COVER AND THE
POSSIBILITY OF ANY LIGHT SHRA/SPRINKLES THROUGH EARLY THIS EVENING.
OTHERWISE... QUIET WEATHER WILL CONTINUE TO BE THE THEME THROUGH
FRIDAY AS WE CONTINUE TO SLOWLY WARM WITH THE BUILDING UPPER RIDGE.
LATEST WATER VAPOR IMAGERY AND RAP UPPER AIR ANALYSES SHOWS THE ALL
TOO FAMILIAR PATTERN OF THE UPPER RIDGE TO OUR WEST AND UPPER TROUGH
TO OUR EAST. HOWEVER... FINALLY STARTING TO SEE SOME CHANGE IN
THIS... WHICH WILL GET FURTHER ACCELERATED NEXT WEEK AS RIDGE
BROADENS AND FLATTENS OVER THE CONUS AND EXERTS ITS MAIN PROMINENCE
OVER THE CENTER PART OF THE COUNTRY. IN THE MEANTIME... WE COULD SEE
SOME SHRA AND/OR SPRINKLES THROUGH EARLY THIS EVENING AS SOME
LINGERING LOW LEVEL INSTABILITY HELPS PRODUCE SOME TCU WITH PERHAPS
SOME PCPN MANAGING TO FALL OUT OF IT. WE WILL BEGIN TO GET INTO
RETURN FLOW ON FRIDAY AS THE SURFACE HIGH MOVES INTO THE EASTERN
GREAT LAKES... BUT ANY MEANINGFUL WARM ADVECTION WILL WAIT UNTIL
BEYOND THAT POINT. FRIDAY SHOULD BE SIMILAR... BUT SLIGHTLY
WARMER... THAN TODAY WITHOUT ANY SHRA/SPRINKLE CHANCE AS WARMER AIR
ALOFT AND ASSOCIATED SUBSIDENCE WORK INTO THE AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 339 PM CDT THU AUG 15 2013
MORE SUMMERLIKE PATTERN TAKES HOLD LATE IN THE WEEKEND AND LINGERS
THROUGHOUT THE WEEK. THE UPPER RIDGE OVER THE PLAINS CONTINUES TO
GRADUALLY EXPAND EASTWARD FRIDAY NIGHT THROUGH THE UPCOMING
WEEKEND. A DRY AND WARMING PATTERN IS EXPECTED OVER THE NEXT SEVEN
DAYS. SOME OF THE GUIDANCE DOES MANAGE TO GENERATE LIGHT
PRECIPITATION NEAR THEN MN/SD BORDER OVER THE WEEKEND ALONG A DIFFUSE
MID LEVEL BOUNDARY. THE MOISTURE MIGHT BE A BIT OVERDONE SO WILL
CONTINUE TO LEAVE DRY MENTION. BY SUNDAY...HIGHS WILL BE ABOVE
CLIMATE NORMALS WITH TEMPS IN THE 80S. AS MENTIONED IN OUR
DISCUSSION YESTERDAY...THE CENTRAL ATLANTIC RIDGE IS EXPECTED TO
DRIFT SOUTHWEST WITH TIME. THE ENSM FORECAST SUPPORTS THIS WITH
KEEPING POSITIVE HEIGHT ANOMALIES FARTHER SOUTH THROUGH THE END OF
THE MONTH. THIS DISPLACEMENT OF THE ATLANTIC RIDGE WILL ALLOW THE
PERSISTENT EAST COAST TROUGH /OUR LOCAL NORTHWEST FLOW/ A CHANCE
TO SHIFT EAST. THE MODELS COMING INTO MUCH BETTER AGREEMENT IN THE
EXTENDED. WHILE THE RIDGE DOES BECOME FLATTER EARLY NEXT WEEK AS A
SERIES OF SHORTWAVES TRACK JUST NORTH OF THE CANADIAN BORDER. A
BOUNDARY APPROACHES THE REGION ON MONDAY...BUT ALL MODELS DISSOLVE
THIS FEATURE NORTHWEST OF THE FORECAST AREA. THE OPERATIONAL GFS
AND TO SOME DEGREE THE ECMWF SHOW THE A GLIMPSE OF THE WARMING
TREND THIS WEEKEND WITH 80S...BUT THE WARM UP BEGINS IN EARNEST
EARLY NEXT WEEK. 850 MB TEMPS GET BACK UP INTO THE UPPER TEENS AND
LOWER 20S. GIVEN THE DRY ANTECEDENT CONDITIONS AND EXPECTED
BUILDING RIDGE...MID TO UPPER 80S SEEM EASILY OBTAINABLE NEXT
WEEK...AND WE SHOULD ONCE AGAIN SEE 90 DEGREES FOR THE FIRST TIME
IN OVER A MONTH. MIXING TO 850-750 MB WITH A SLIGHT SUPER
ADIABATIC LAYER GIVES NEAR RECORD TEMPS OF 95-99 DEGREES. SO...WE
WILL NEED TO MONITOR THE TEMP ADVECTION AND MIXING POTENTIAL.
CLOUD COVER ASIDE...THIS HAS A CHANCE TO BE A HOT STRETCH.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 727 PM CDT THU AUG 15 2013
VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD...WITH POSSIBLY THE
EXCEPTION OF SOME PATCHY FOG DEVELOPMENT OVERNIGHT. THAT POTENTIAL
SEEMS SLIGHTLY HIGHER IN SW MN...SO HAVE INCLUDED A 3SM MENTION AT
KRWF. OTHERWISE...MOSTLY CLEAR SKIES AND LIGHT WINDS INTO FRIDAY.
FEW-SCT CUMULUS CLOUDS ARE EXPECTED ON FRIDAY...WITH SOUTHERLY
WINDS INCREASING TO 5-10 KTS.
KMSP...
A FEW CLOUDS FROM 5-7KFT THROUGH THE PERIOD...WITH FLEETING SCT
CIRRUS. SSW WINDS AOB 5 KTS OVERNIGHT...INCREASING TO AROUND 8 KTS
FRIDAY AFTERNOON.
/OUTLOOK FOR KMSP/
SAT...VFR. WINDS S 10-15 KTS.
SUN...VFR. WINDS SSW 10-15 KTS.
MON...VFR. WINDS SW 10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...CLF
LONG TERM...TRH
AVIATION...LS
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
551 AM CDT WED AUG 14 2013
.UPDATED FOR 12Z AVIATION DISCUSSION...
ISSUED AT 542 AM CDT WED AUG 14 2013
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 336 AM CDT WED AUG 14 2013
AS HAS BEEN THE CASE FOR THE LAST FEW WEEKS...EARLY MORNING WATER
VAPOR IMAGERY AND 500MB HEIGHTS AND WINDS IDENTIFIED A RIDGE ACROSS
THE EASTERN SPINE OF THE CANADIAN ROCKIES...WITH A LONGWAVE TROUGH
OVER THE GREAT LAKES AND EASTERN CANADA. NORTHWEST FLOW PERSISTED
OVER THE UPPER MIDWEST...WITH A COUPLE EMBEDDED SHORTWAVES OVER THE
HIGH PLAINS. ONE OF THESE SHORTWAVES WAS THE DRIVING FORCE BEHIND AN
MCS TRACKING EASTWARD ALONG THE NE/SD BORDER. HIRES MODELS SUCH AS THE
HOPWRF AND HRRR TAKE THIS CONVECTION DOWN THE MISSOURI RIVER VALLEY
THIS MORNING AND KEEPS MN/WI FREE FROM ANY PRECIP. THIS SOLUTION
MAKES SENSE GIVEN THE SUBSIDENCE BENEATH THE NORTHWEST FLOW IN
ASSOCIATION WITH NEGATIVE VORTICITY ADVECTION THAT IS FORECAST TO
MOVE ACROSS THE REGION THIS AFTERNOON. THEREFORE EXPECT ANOTHER DAY
OF LIGHT WINDS AND A FEW AFTERNOON CLOUDS WITH BASES AROUND 6000FT.
TEMPERATURES WILL BE SIMILAR TO YESTERDAY...BUT THE THIN CIRRUS FROM
THE CONVECTION OUT WEST MAY KEEP THEM A DEGREE OR TWO COOLER THAN
TUESDAYS HIGHS...ESPECIALLY IN WESTERN MN.
LATER TONIGHT ANOTHER SHORTWAVE IS FORECAST TO MOVE ACROSS THE
MISSOURI RIVER VALLEY...AND THIS WILL PRODUCE ANOTHER ROUND OF
SHOWERS AND THUNDERSTORMS...WITH DEVELOPMENT EXPECTED A LITTLE
FARTHER EAST. THEREFORE EXPECT WESTERN MN TO BE DRY FOR MOST OF THE
PERIOD...BUT DID INTRODUCE A SLIGHT CHANCE OF POPS ACROSS THE
SOUTHWEST EARLY THURSDAY MORNING.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 336 AM CDT WED AUG 14 2013
THE WEAK MCS FROM WEDNESDAY NIGHT WILL BE LOCATED OVER WESTERN IA
AT THE BEGINNING OF THE PERIOD. EXTENSIVE CLOUDINESS AND POSSIBLE
RAIN ACROSS IA WILL KEEP TEMPERATURES COOL THERE...WHILE MORNING
SUNSHINE SHOULD ALLOW FOR A QUICK REBOUND BACK INTO THE 70S ACROSS
MN/WI. SYNOPTIC SOUTHERLY FLOW WILL ADVECT THE COOL BOUNDARY
NORTHWARD BY AFTERNOON...WHICH COULD PRODUCE A COUPLE SHOWERS OR
STORMS ACROSS SRN MN AS THE ATMOSPHERE BECOMES WEAKLY UNSTABLE.
THERE IS A PRONOUNCED CAP BETWEEN 600-700 MB WHICH WILL LIMIT
COVERAGE TO 20-30 PCT...AND IF CLOUD COVER IS HIGHER THAN FORECAST
THE INSTABILITY MAY NEVER EVEN MATERIALIZE.
BY FRIDAY...STRONG RIDGING WILL EMERGE OVER THE WESTERN HIGH
PLAINS FROM THE ROCKIES. SOUTH/SOUTHEASTERLY FLOW AT THE SURFACE
WILL KEEP TEMPERATURES IN THE UPPER 70S/LOWER 80S LOCALLY...BUT
TEMPERATURES WILL INCH UPWARD EACH DAY AS THE RIDGE CONTINUES
BUILDING EAST. BY SATURDAY...AN IMPRESSIVE THERMAL RIDGE WILL BE
IN PLACE OVER THE WESTERN DAKOTAS. AS THE WEEKEND PROGRESSES...
AND ESPECIALLY BY EARLY NEXT WEEK...STRONGER MID AND UPPER LEVEL
FLOW WILL BECOME ESTABLISHED OVER SOUTHERN CANADA. THIS WILL BRING
THE RIDGING FURTHER EAST INTO THE UPPER MIDWEST AND MISSISSIPPI
VALLEY. 850 MB TEMPS RISE TO AROUND 20C AND 925 MB TEMPS RISE INTO
THE MID 20S C...THUS SUMMER WILL FINALLY RETURN WITH HIGHS IN THE
MID 80S TO LOWER 90S. POPS APPEAR LOW TO NIL GIVEN THE LACK OF
FORCING. ANY CHANCES WILL BE DRIVEN ON LOCAL FEATURES TOO
DIFFICULT TO PINPOINT THIS FAR OUT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 542 AM CDT WED AUG 14 2013
HIGH PRESSURE WILL REMAIN IN CONTROL WITH VFR CONDITIONS EXPECTED
THROUGHOUT. VARIABLE MORNING WINDS WILL BECOME WEST SOUTHWESTERLY
TODAY. HIGH CLOUDS WILL INCREASE TONIGHT AND SHOULD LIMIT THE FOG
POTENTIAL THURSDAY MORNING.
KMSP...
VFR CONDITIONS THROUGHOUT. LIGHT AND VARIABLE WINDS WILL GRADUALLY
TAKE ON A WEST SOUTHWESTERLY DIRECTION TODAY. LOOK FOR FLAT
CUMULUS AT AROUND 6000FT THIS AFTERNOON...WITH HIGH CLOUDS
INCREASING LATER TONIGHT.
/OUTLOOK FOR KMSP/
THU...VFR. WINDS SW AT 05KTS.
FRI...VFR WITH -SHRA/TSRA POSSIBLE. WINDS S AT 05G10KTS.
SAT...VFR. WINDS SSW AT 10G15KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...JRB
LONG TERM...BORGHOFF
AVIATION...JRB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
336 AM CDT WED AUG 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 336 AM CDT WED AUG 14 2013
AS HAS BEEN THE CASE FOR THE LAST FEW WEEKS...EARLY MORNING WATER
VAPOR IMAGERY AND 500MB HEIGHTS AND WINDS IDENTIFIED A RIDGE ACROSS
THE EASTERN SPINE OF THE CANADIAN ROCKIES...WITH A LONGWAVE TROUGH
OVER THE GREAT LAKES AND EASTERN CANADA. NORTHWEST FLOW PERSISTED
OVER THE UPPER MIDWEST...WITH A COUPLE EMBEDDED SHORTWAVES OVER THE
HIGH PLAINS. ONE OF THESE SHORTWAVES WAS THE DRIVING FORCE BEHIND AN
MCS TRACKING EASTWARD ALONG THE NE/SD BORDER. HIRES MODELS SUCH AS THE
HOPWRF AND HRRR TAKE THIS CONVECTION DOWN THE MISSOURI RIVER VALLEY
THIS MORNING AND KEEPS MN/WI FREE FROM ANY PRECIP. THIS SOLUTION
MAKES SENSE GIVEN THE SUBSIDENCE BENEATH THE NORTHWEST FLOW IN
ASSOCIATION WITH NEGATIVE VORTICITY ADVECTION THAT IS FORECAST TO
MOVE ACROSS THE REGION THIS AFTERNOON. THEREFORE EXPECT ANOTHER DAY
OF LIGHT WINDS AND A FEW AFTERNOON CLOUDS WITH BASES AROUND 6000FT.
TEMPERATURES WILL BE SIMILAR TO YESTERDAY...BUT THE THIN CIRRUS FROM
THE CONVECTION OUT WEST MAY KEEP THEM A DEGREE OR TWO COOLER THAN
TUESDAYS HIGHS...ESPECIALLY IN WESTERN MN.
LATER TONIGHT ANOTHER SHORTWAVE IS FORECAST TO MOVE ACROSS THE
MISSOURI RIVER VALLEY...AND THIS WILL PRODUCE ANOTHER ROUND OF
SHOWERS AND THUNDERSTORMS...WITH DEVELOPMENT EXPECTED A LITTLE
FARTHER EAST. THEREFORE EXPECT WESTERN MN TO BE DRY FOR MOST OF THE
PERIOD...BUT DID INTRODUCE A SLIGHT CHANCE OF POPS ACROSS THE
SOUTHWEST EARLY THURSDAY MORNING.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 336 AM CDT WED AUG 14 2013
THE WEAK MCS FROM WEDNESDAY NIGHT WILL BE LOCATED OVER WESTERN IA
AT THE BEGINNING OF THE PERIOD. EXTENSIVE CLOUDINESS AND POSSIBLE
RAIN ACROSS IA WILL KEEP TEMPERATURES COOL THERE...WHILE MORNING
SUNSHINE SHOULD ALLOW FOR A QUICK REBOUND BACK INTO THE 70S ACROSS
MN/WI. SYNOPTIC SOUTHERLY FLOW WILL ADVECT THE COOL BOUNDARY
NORTHWARD BY AFTERNOON...WHICH COULD PRODUCE A COUPLE SHOWERS OR
STORMS ACROSS SRN MN AS THE ATMOSPHERE BECOMES WEAKLY UNSTABLE.
THERE IS A PRONOUNCED CAP BETWEEN 600-700 MB WHICH WILL LIMIT
COVERAGE TO 20-30 PCT...AND IF CLOUD COVER IS HIGHER THAN FORECAST
THE INSTABILITY MAY NEVER EVEN MATERIALIZE.
BY FRIDAY...STRONG RIDGING WILL EMERGE OVER THE WESTERN HIGH
PLAINS FROM THE ROCKIES. SOUTH/SOUTHEASTERLY FLOW AT THE SURFACE
WILL KEEP TEMPERATURES IN THE UPPER 70S/LOWER 80S LOCALLY...BUT
TEMPERATURES WILL INCH UPWARD EACH DAY AS THE RIDGE CONTINUES
BUILDING EAST. BY SATURDAY...AN IMPRESSIVE THERMAL RIDGE WILL BE
IN PLACE OVER THE WESTERN DAKOTAS. AS THE WEEKEND PROGRESSES...
AND ESPECIALLY BY EARLY NEXT WEEK...STRONGER MID AND UPPER LEVEL
FLOW WILL BECOME ESTABLISHED OVER SOUTHERN CANADA. THIS WILL BRING
THE RIDGING FURTHER EAST INTO THE UPPER MIDWEST AND MISSISSIPPI
VALLEY. 850 MB TEMPS RISE TO AROUND 20C AND 925 MB TEMPS RISE INTO
THE MID 20S C...THUS SUMMER WILL FINALLY RETURN WITH HIGHS IN THE
MID 80S TO LOWER 90S. POPS APPEAR LOW TO NIL GIVEN THE LACK OF
FORCING. ANY CHANCES WILL BE DRIVEN ON LOCAL FEATURES TOO
DIFFICULT TO PINPOINT THIS FAR OUT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1048 PM CDT TUE AUG 13 2013
HIGH PRESSURE WILL DOMINATE ACROSS THE TAF SITES OVERNIGHT. STRONG
COOLING WILL LEAD TO THE CROSSOVER TEMPERATURE BEING EXCEEDED FOR
FOG PURPOSES AT KSTC...KRNH AND KEAU. HAVE HIT THE FOG HARDER AT
THESE THREE SITES WITH PREDOMINATE 1 1/2SM TEMPO 1/4SM. TIMING
REMAINS AN ISSUE WITH 08Z-12Z BEING SIMILAR TIMING TO LAST NIGHT.
HOWEVER...SOME FOG IS POSSIBLE BETWEEN 06Z-08Z. WINDS WILL
INCREASE TO 6-9 KNOTS FROM THE WSW AFTER 15Z ON WEDNESDAY ALONG
WITH SCT-BKN060 DEVELOPING.
KMSP...VFR THROUGH THE PERIOD. LIGHT WINDS OVERNIGHT BECOMING WSW
7-9 KNOTS BY LATE WEDNESDAY MORNING.
/OUTLOOK FOR KMSP/
THU...VFR. WINDS SW 5 KTS.
FRI...VFR. SLIGHT CHANCE ISOLD SHRA/TS. WINDS S 8 KTS.
SAT...VFR. WINDS SSW 10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...JRB
LONG TERM...BORGHOFF
AVIATION...RAH
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
257 PM CDT Wed Aug 14 2013
.SHORT TERM...(This Evening through Friday Afternoon)
Issued at 257 PM CDT WED AUG 14 2013
The main focus in the short-term remains a series of shortwave
troughs sinking southeastward across the Plains this evening,
Thursday, and into early Friday. Showers and isolated storms have
developed over portions of eastern Nebraska in association with a
wave currently pushing southeast toward the forecast area; however,
ongoing precipitation will continue to move into fairly dry air this
evening, and may struggle against entrainment. Additionally, upper-
level flow may push the main area of precipitation more east than
south, keeping the bulk of any falling precipitation in central and
southern Iowa. Short-term precipitation trends from the HRRR have
been fairly consistent today, and also generally limit the south and
eastward expansion of showers for this evening and tonight. For now,
have kept PoPs very low and confined to far northwest Missouri prior
to 06z, then have begun to increase chances in the NW to account for
possible regeneration as the low-level jet kicks up early Thursday
morning.
The next system will follow on the heels of tonight`s as it drops
down from eastern Montana on Thursday. Models continue to indicate
that the reinforcement of the eastern trough by a second upper low,
and the retrograding of a broad upper high, will result in more
meridional flow across the Plains for Thursday and Friday. This
subtle change will send the second wave a bit west of the forecast
area, keeping the better rain chances mainly across portions of
central and eastern Kansas. Have left some slight to low-end chance
PoPs mainly across the western tier or two of counties on Thursday
afternoon and Thursday night, but these could likely be cut further
if model trends continue in this direction. Any precipitation that
does brush the area will sink southward on Friday morning, leaving
behind quiet conditions by Friday afternoon.
Temperatures through the period will remain ~10 degrees below normal
as cool air continues to filter down the trough and into the eastern
Plains and Ohio River valley, with highs generally topping out in
the upper 70s to lower 80s, and lows in the 50s to lower 60s under
surface high pressure.
.LONG TERM...(Friday Evening through Wednesday)
Issued at 257 PM CDT WED AUG 14 2013
A quiet medium range forecast for the Central Plains as mid-level
ridging currently building over the Rockies begins to move
eastward. Despite the increasing heights, Saturday will likely
remain below seasonal normals as surface and low-level winds remain
light to southeast. By Sunday, we`ll begin to see a steady climb
back to or even above normal as winds turn southerly and warmer air
begins to advect northward.
The first half of next week will again feature quiet conditions as
mid-level flow remains weak. Temperatures will have a chance to
return to the 90 degree mark by Tuesday and Wednesday, a rare feat
this August.
&&
.AVIATION...(For the 18Z TAFS through 18Z Thursday Afternoon)
Issued at 1222 PM CDT WED AUG 14 2013
VFR conditions are expected to prevail across the majority of the
region through the forecast period. A midlevel stratus deck with
bases around 4-5 kft and a few isolated showers may begin to work
into far northwest MO around sunrise Thursday, but should not impact
flight category.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
SHORT TERM...Laflin
LONG TERM...Dux
AVIATION...Laflin
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
933 PM CDT THU AUG 15 2013
.SYNOPSIS...
ISSUED AT 333 PM CDT THU AUG 15 2013
CURRENTLY...AN UPPER LEVEL DISTURBANCE IS MOVING SOUTH-SOUTHEAST
ACROSS SOUTH DAKOTA IN NORTHWEST FLOW ALOFT. AN UPPER LEVEL RIDGE
EXTENDS NORTHWARD FROM THE FOUR CORNERS REGION TO SASKATCHEWAN AND
AN UPPER LEVEL LOW EXISTS OVER QUEBEC. A SURFACE BOUNDARY
CURRENTLY EXTENDS NORTHWESTWARD FROM FRONTIER COUNTY THROUGH
GARDEN COUNTY AND INTO NORTHWESTERN NEBRASKA. ALSO...LOW CLOUDS
HAVE BEEN PERSISTENT OVER PARTS OF NORTH-CENTRAL NEBRASKA TODAY.
&&
.UPDATE...
ISSUED AT 932 PM CDT THU AUG 15 2013
UPDATED TO REMOVE REMAINING PRECIP CHANCES AND TO FINE TUNE
AREAS/PATCHY FOG GRIDS. OTHERWISE REMAINDER OF THE FCST LOOKS GOOD.
UPDATE ISSUED AT 654 PM CDT THU AUG 15 2013
HAVE UPDATED TO REMOVE PRECIPITATION CHANCES FOR ALL BUT THE FAR
SOUTHERN PORTION OF THE FCST AREA THIS EVENING BASED ON LATEST
SATELLITE/RADAR TRENDS AND GUIDANCE FROM SHORT RANGE MODELS. THE
BIGGEST FCST CHALLENGE TONIGHT WILL BE TIMING THE ONSET OF FOG
ALONG AND EAST OF THE HIGHWAY 83 CORRIDOR. SOME VISIBILITIY
RESTRICTIONS ALREADY ALONG THE HIGHWAY 281 CORRIDOR IN HOLT COUNTY
BASED ON OBS AND WEB CAMS. WHILE THERE MAY BE SOME DECREASE IN
CLOUDS BRIEFLY IN THE NORTH CENTRAL ARAS...EXPECT THEM TO COME
BACK IN LATE THIS EVENING AND DURING THE EARLY MORNING HOURS AS
THE FCST AREA EXPERIENCES INCREASING SUBSIDENCE FROM EXITING UPPER
PV ANOMALY WHILE MOIST BUT LIGHT UPSLOPE FLOW CONTINUES. PREVIOUS
FCST HAD THIS ALERADY...BUT HAVE MOVED UP THE TIMING A BIT IN THE
EASTERN PORTION OF THE FCST AREA.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 333 PM CDT THU AUG 15 2013
STARTING TO SEE SOME CUMULUS DEVELOPMENT ALONG STATIONARY SURFACE
BOUNDARY EXTENDING TO THE NW FROM FRONTIER COUNTY THROUGH OGALLALA
AND NWWD. BELIEVE THIS WOULD BE THE BEST AREA FOR THUNDERSTORM
DEVELOPMENT THIS AFTERNOON...WITH ANY STORMS MOVING SOUTHEASTWARD
AT AROUND 20 KTS. MODELS INDICATE 0-6 KM SHEAR OF 30-35 KTS
ALTHOUGH SPC MESOANALYSIS DATA IS SHOWING SHEAR UNDER 30 KTS AS OF
20Z. THERE MAY BE A FEW ISOLATED SEVERE STORMS THIS AFTN/EVE...BUT
THE BEST CHANCE WOULD BE SOUTH OF I-80. HAVE TRIMMED POPS AND
THUNDERSTORM COVERAGE A BIT ACROSS THE AREA TONIGHT BASED ON
LATEST MODEL DATA AND TRENDS. HRRR MODEL FROM 18Z HAS A FEW STORMS
JUST WEST OF NORTH PLATTE AND AREAS SE...MOVING SE TONIGHT. EMC
WRF MODEL HAS A FAIR AMOUNT OF CONVECTION NORTH TO THE SD BORDER
HOWEVER...ALTHOUGH ITS NOT AS LIKELY. THUNDERSTORMS SHOULD COME TO
AN END IN THE EVENING ACROSS THE AREA AS THE UPPER LEVEL WAVE
MOVES THROUGH THE REGION. MODELS ARE POINTING TOWARD MORE FOG AND
LOW STRATUS TONIGHT...ESPECIALLY CENTRAL AND EAST. HAVE INCLUDED
FOG IN THE FORECAST FOR MOST OF THE AREA. TOMORROW...AFTER LOW
CLOUDS AND FOG HAVE DISSIPATED...FAIR SKIES AND TEMPS IN THE MID
70S EAST TO UPPER 80S WEST ARE EXPECTED.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 333 PM CDT THU AUG 15 2013
MID TERM...FRIDAY NIGHT THROUGH SUNDAY...RIDGING WILL CONTINUE TO
BUILD ACROSS THE CENTRAL PLAINS FRIDAY NIGHT THROUGH SATURDAY
NIGHT...WITH TEMPERATURES THE MAIN FORECAST CHALLENGE...FOLLOWED BY
PRECIPITATION CHANCES IN THE FAR WEST SUNDAY AFTERNOON. FOR FRIDAY
NIGHT...SURFACE HIGH PRESSURE WILL DRIFT EAST INTO THE MIDDLE
MISSISSIPPI VALLEY WITH A LEE SIDE TROUGH BEGINNING TO DEEPEN ACROSS THE
FRONT RANGES OF COLORADO AND WYOMING. SRLY WINDS WILL BEGIN TO
INCREASE LATE FRIDAY IN RESPONSE...AND ARE NOT EXPECTED TO TOTALLY
DECOUPLE FRIDAY NIGHT. THIS WILL LEAD TO SLIGHTLY WARMER MIN TEMPS
SATURDAY MORNING COMPARED TO FRIDAY MORNING. THE MET AND MAV
GUIDANCE ARE IN DECENT AGREEMENT WITH LOWS SATURDAY MORNING SO A
BLEND WILL BE UTILIZED...THEN SCALED UPWARD A DEGREE OR TWO DUE TO
INCREASED MIXING. MAV AND MET GUIDANCE TEMPS DIVERGE ON
SATURDAY...WITH THE MAV 3 TO 6 DEGREES COOLER THAN THE MUCH WARMER
MET. UTILIZED THE BIAS CORRECTED CONSALL GUIDANCE FOR HIGHS
SATURDAY...WHICH RESULTED IN A COMPROMISE BETWEEN THE MET AND MAV
NUMBERS. THIS LED TO HIGHS IN THE MIDDLE 80S IN THE EASTERN CWA...TO
THE LOWER 90S IN THE PANHANDLE...WHERE DEW POINTS IN THE LOWER 50S
ARE EXPECTED SAT AFTERNOON. FOR SUNDAY...HIGHS WILL MIRROR SATURDAYS
FCST...WITH THE EXCEPTION OF THE EASTERN ZONES WHERE SLIGHTLY WARMER
TEMPS ARE EXPECTED THANKS TO WARMER H85 AIR. HIGHS SUNDAY WILL RANGE
FROM THE UPPER 80S TO LOWER 90S IN THE PANHANDLE AND FAR WEST. BY
SUNDAY AFTERNOON...THE LATEST NAM IS HINTING AT BREAKING DOWN THE
RIDGE AND INITIATING CONVECTION ACROSS THE PANHANDLE AND FAR WESTERN
ZONES LATE SUNDAY AFTERNOON. THE LATEST GFS...KEEPS THIS CONVECTION
CONFINED TO THE FRONT RANGES OF COLORADO AND WYOMING...THANKS TO
VERY WEAK MID LEVEL STEERING WINDS. INHERITED FCST WAS DRY SUNDAY
AFTERNOON...AND INTEND TO KEEP IT THAT WAY...EVEN IN LIGHT OF THE
LATEST 12Z NAM SOLN.
LONG TERM...SUNDAY NIGHT THROUGH THURSDAY...THERE ARE TWO SCHOOLS
OF THOUGHT WITH THE EXTENDED FCST...A...DRY AND VERY WARM CONDS
WILL PERSIST WELL INTO THE MIDDLE OF NEXT WEEK-12Z GFS...AND B...A
BREAK DOWN IN THE RIDGE ACROSS THE CENTRAL CONUS LEADING TO COOLER
AND WETTER CONDS ACROSS THE AREA-ECMWF. GLANCING AT LAST NIGHTS
ENSEMBLES...THE MEAN NCEP ENSEMBLE MEAN HAS A BREAKDOWN IN THE
WESTERN CONUS RIDGING EARLY IN THE WEEK WITH A FAIRLY ACTIVE
PATTERN DEVELOPING BY MIDWEEK. IN CONTRAST...THE OPERATIONAL GFS
FROM THIS MORNING HAS A CLOSED LOW OVER THE CENTRAL CA COAST. THE
LATTER SOLN...WOULD TEND TO FAVOR A DRY AND WARMER FCST AS RIDGING
WILL AMPLIFY DOWNSTREAM OF THE CLOSED CA LOW. NO SURPRISE...THE
LATEST MEX GUIDANCE FROM THIS MORNING HAS LOWER TO MIDDLE 90S FOR
HIGHS NEXT WEEK WITH DRY CONDS EXPECTED. SINCE THE OPERATIONAL GFS
IS KIND OF AN OUTLIER WITH THE ENSEMBLE FCSTS...WILL FAVOR COOLER
TEMPS IN THE 80S TO LOWER 90S FOR TEMPS NEXT WEEK. AS FOR PCPN
CHANCES...CAN`T SEE MORE THAN A 20 PCT CHANCE TOWARD THE MIDDLE OF
NEXT WEEK...AS WEAK DYNAMICS WILL CONTINUE WELL INTO NEXT WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 654 PM CDT THU AUG 15 2013
LOW CLOUDS HAVE STAYED AROUND ALL DAY AT KVTN AND WILL EXPECT THEM
TO REMAIN...ALTHOUGH VISIBLE SATELLITE TRENDS AND MODEL SOUNDINGS
SUGGEST THAT THE NORTH CENTRAL PART OF THE STATE AROUND KVTN WILL
SCT OUT FOR AN HOUR OR TWO...BEFORE LOW CLOUDS AND FOG ROLL BACK IN.
SYNOPTIC PATTERN IS FAVORABLE FOR FOG AS UPPER HEIGHTS RISE ABOVE
MOIST LOW LEVELS AND LIMITED DEEP MIXING. TAF HAS VSBY DECREASING TO
AIRPORT MINS FOR KVTN. FURTHER SOUTH NEAR THE KLBF TAF...WOULD
EXPECT REMAINING CLOUDS ASSOCIATED WITH CONVECTION TO DECREASE AFTER
SUNSET AS MID LEVEL LAPSE RATES BECOME UNFAVORABLE. SHOULD BE A
COUPLE HOURS OF SKC BEFORE MOIST LOW LEVELS AND LIGHT EASTERLY
UPSLOPE FLOW INITIATE FOG. LIFR LIKELY AT KLBF AND KVTN AND REALLY
ALONG AND EAST OF HIGHWAY 83 INTO THE MORNING HOURS. ONCE FOG/LOW
CLOUDS BURN OFF MID MORNING WILL LIKELY SEE SCT-BKN CU FIELD
DEVELOP...BUT NO MENTION OF SHRA/TSRA AT THIS TIME.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JWS
SYNOPSIS...KNUTSVIG
SHORT TERM...KNUTSVIG
LONG TERM...CLB
AVIATION...JWS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
654 PM CDT THU AUG 15 2013
.SYNOPSIS...
ISSUED AT 333 PM CDT THU AUG 15 2013
CURRENTLY...AN UPPER LEVEL DISTURBANCE IS MOVING SOUTH-SOUTHEAST
ACROSS SOUTH DAKOTA IN NORTHWEST FLOW ALOFT. AN UPPER LEVEL RIDGE
EXTENDS NORTHWARD FROM THE FOUR CORNERS REGION TO SASKATCHEWAN AND
AN UPPER LEVEL LOW EXISTS OVER QUEBEC. A SURFACE BOUNDARY
CURRENTLY EXTENDS NORTHWESTWARD FROM FRONTIER COUNTY THROUGH
GARDEN COUNTY AND INTO NORTHWESTERN NEBRASKA. ALSO...LOW CLOUDS
HAVE BEEN PERSISTENT OVER PARTS OF NORTH-CENTRAL NEBRASKA TODAY.
&&
.UPDATE...
ISSUED AT 654 PM CDT THU AUG 15 2013
HAVE UPDATED TO REMOVE PRECIPITATION CHANCES FOR ALL BUT THE FAR
SOUTHERN PORTION OF THE FCST AREA THIS EVENING BASED ON LATEST
SATELLITE/RADAR TRENDS AND GUIDANCE FROM SHORT RANGE MODELS. THE
BIGGEST FCST CHALLENGE TONIGHT WILL BE TIMING THE ONSET OF FOG
ALONG AND EAST OF THE HIGHWAY 83 CORRIDOR. SOME VISIBILITIY
RESTRICTIONS ALREADY ALONG THE HIGHWAY 281 CORRIDOR IN HOLT COUNTY
BASED ON OBS AND WEB CAMS. WHILE THERE MAY BE SOME DECREASE IN
CLOUDS BRIEFLY IN THE NORTH CENTRAL ARAS...EXPECT THEM TO COME
BACK IN LATE THIS EVENING AND DURING THE EARLY MORNING HOURS AS
THE FCST AREA EXPERIENCES INCREASING SUBSIDENCE FROM EXITING UPPER
PV ANOMALY WHILE MOIST BUT LIGHT UPSLOPE FLOW CONTINUES. PREVIOUS
FCST HAD THIS ALERADY...BUT HAVE MOVED UP THE TIMING A BIT IN THE
EASTERN PORTION OF THE FCST AREA.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 333 PM CDT THU AUG 15 2013
STARTING TO SEE SOME CUMULUS DEVELOPMENT ALONG STATIONARY SURFACE
BOUNDARY EXTENDING TO THE NW FROM FRONTIER COUNTY THROUGH OGALLALA
AND NWWD. BELIEVE THIS WOULD BE THE BEST AREA FOR THUNDERSTORM
DEVELOPMENT THIS AFTERNOON...WITH ANY STORMS MOVING SOUTHEASTWARD
AT AROUND 20 KTS. MODELS INDICATE 0-6 KM SHEAR OF 30-35 KTS
ALTHOUGH SPC MESOANALYSIS DATA IS SHOWING SHEAR UNDER 30 KTS AS OF
20Z. THERE MAY BE A FEW ISOLATED SEVERE STORMS THIS AFTN/EVE...BUT
THE BEST CHANCE WOULD BE SOUTH OF I-80. HAVE TRIMMED POPS AND
THUNDERSTORM COVERAGE A BIT ACROSS THE AREA TONIGHT BASED ON
LATEST MODEL DATA AND TRENDS. HRRR MODEL FROM 18Z HAS A FEW STORMS
JUST WEST OF NORTH PLATTE AND AREAS SE...MOVING SE TONIGHT. EMC
WRF MODEL HAS A FAIR AMOUNT OF CONVECTION NORTH TO THE SD BORDER
HOWEVER...ALTHOUGH ITS NOT AS LIKELY. THUNDERSTORMS SHOULD COME TO
AN END IN THE EVENING ACROSS THE AREA AS THE UPPER LEVEL WAVE
MOVES THROUGH THE REGION. MODELS ARE POINTING TOWARD MORE FOG AND
LOW STRATUS TONIGHT...ESPECIALLY CENTRAL AND EAST. HAVE INCLUDED
FOG IN THE FORECAST FOR MOST OF THE AREA. TOMORROW...AFTER LOW
CLOUDS AND FOG HAVE DISSIPATED...FAIR SKIES AND TEMPS IN THE MID
70S EAST TO UPPER 80S WEST ARE EXPECTED.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 333 PM CDT THU AUG 15 2013
MID TERM...FRIDAY NIGHT THROUGH SUNDAY...RIDGING WILL CONTINUE TO
BUILD ACROSS THE CENTRAL PLAINS FRIDAY NIGHT THROUGH SATURDAY
NIGHT...WITH TEMPERATURES THE MAIN FORECAST CHALLENGE...FOLLOWED BY
PRECIPITATION CHANCES IN THE FAR WEST SUNDAY AFTERNOON. FOR FRIDAY
NIGHT...SURFACE HIGH PRESSURE WILL DRIFT EAST INTO THE MIDDLE
MISSISSIPPI VALLEY WITH A LEE SIDE TROUGH BEGINNING TO DEEPEN ACROSS THE
FRONT RANGES OF COLORADO AND WYOMING. SRLY WINDS WILL BEGIN TO
INCREASE LATE FRIDAY IN RESPONSE...AND ARE NOT EXPECTED TO TOTALLY
DECOUPLE FRIDAY NIGHT. THIS WILL LEAD TO SLIGHTLY WARMER MIN TEMPS
SATURDAY MORNING COMPARED TO FRIDAY MORNING. THE MET AND MAV
GUIDANCE ARE IN DECENT AGREEMENT WITH LOWS SATURDAY MORNING SO A
BLEND WILL BE UTILIZED...THEN SCALED UPWARD A DEGREE OR TWO DUE TO
INCREASED MIXING. MAV AND MET GUIDANCE TEMPS DIVERGE ON
SATURDAY...WITH THE MAV 3 TO 6 DEGREES COOLER THAN THE MUCH WARMER
MET. UTILIZED THE BIAS CORRECTED CONSALL GUIDANCE FOR HIGHS
SATURDAY...WHICH RESULTED IN A COMPROMISE BETWEEN THE MET AND MAV
NUMBERS. THIS LED TO HIGHS IN THE MIDDLE 80S IN THE EASTERN CWA...TO
THE LOWER 90S IN THE PANHANDLE...WHERE DEW POINTS IN THE LOWER 50S
ARE EXPECTED SAT AFTERNOON. FOR SUNDAY...HIGHS WILL MIRROR SATURDAYS
FCST...WITH THE EXCEPTION OF THE EASTERN ZONES WHERE SLIGHTLY WARMER
TEMPS ARE EXPECTED THANKS TO WARMER H85 AIR. HIGHS SUNDAY WILL RANGE
FROM THE UPPER 80S TO LOWER 90S IN THE PANHANDLE AND FAR WEST. BY
SUNDAY AFTERNOON...THE LATEST NAM IS HINTING AT BREAKING DOWN THE
RIDGE AND INITIATING CONVECTION ACROSS THE PANHANDLE AND FAR WESTERN
ZONES LATE SUNDAY AFTERNOON. THE LATEST GFS...KEEPS THIS CONVECTION
CONFINED TO THE FRONT RANGES OF COLORADO AND WYOMING...THANKS TO
VERY WEAK MID LEVEL STEERING WINDS. INHERITED FCST WAS DRY SUNDAY
AFTERNOON...AND INTEND TO KEEP IT THAT WAY...EVEN IN LIGHT OF THE
LATEST 12Z NAM SOLN.
LONG TERM...SUNDAY NIGHT THROUGH THURSDAY...THERE ARE TWO SCHOOLS
OF THOUGHT WITH THE EXTENDED FCST...A...DRY AND VERY WARM CONDS
WILL PERSIST WELL INTO THE MIDDLE OF NEXT WEEK-12Z GFS...AND B...A
BREAK DOWN IN THE RIDGE ACROSS THE CENTRAL CONUS LEADING TO COOLER
AND WETTER CONDS ACROSS THE AREA-ECMWF. GLANCING AT LAST NIGHTS
ENSEMBLES...THE MEAN NCEP ENSEMBLE MEAN HAS A BREAKDOWN IN THE
WESTERN CONUS RIDGING EARLY IN THE WEEK WITH A FAIRLY ACTIVE
PATTERN DEVELOPING BY MIDWEEK. IN CONTRAST...THE OPERATIONAL GFS
FROM THIS MORNING HAS A CLOSED LOW OVER THE CENTRAL CA COAST. THE
LATTER SOLN...WOULD TEND TO FAVOR A DRY AND WARMER FCST AS RIDGING
WILL AMPLIFY DOWNSTREAM OF THE CLOSED CA LOW. NO SURPRISE...THE
LATEST MEX GUIDANCE FROM THIS MORNING HAS LOWER TO MIDDLE 90S FOR
HIGHS NEXT WEEK WITH DRY CONDS EXPECTED. SINCE THE OPERATIONAL GFS
IS KIND OF AN OUTLIER WITH THE ENSEMBLE FCSTS...WILL FAVOR COOLER
TEMPS IN THE 80S TO LOWER 90S FOR TEMPS NEXT WEEK. AS FOR PCPN
CHANCES...CAN`T SEE MORE THAN A 20 PCT CHANCE TOWARD THE MIDDLE OF
NEXT WEEK...AS WEAK DYNAMICS WILL CONTINUE WELL INTO NEXT WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 654 PM CDT THU AUG 15 2013
LOW CLOUDS HAVE STAYED AROUND ALL DAY AT KVTN AND WILL EXPECT THEM
TO REMAIN...ALTHOUGH VISIBLE SATELLITE TRENDS AND MODEL SOUNDINGS
SUGGEST THAT THE NORTH CENTRAL PART OF THE STATE AROUND KVTN WILL
SCT OUT FOR AN HOUR OR TWO...BEFORE LOW CLOUDS AND FOG ROLL BACK IN.
SYNOPTIC PATTERN IS FAVORABLE FOR FOG AS UPPER HEIGHTS RISE ABOVE
MOIST LOW LEVELS AND LIMITED DEEP MIXING. TAF HAS VSBY DECREASING TO
AIRPORT MINS FOR KVTN. FURTHER SOUTH NEAR THE KLBF TAF...WOULD
EXPECT REMAINING CLOUDS ASSOCIATED WITH CONVECTION TO DECREASE AFTER
SUNSET AS MID LEVEL LAPSE RATES BECOME UNFAVORABLE. SHOULD BE A
COUPLE HOURS OF SKC BEFORE MOIST LOW LEVELS AND LIGHT EASTERLY
UPSLOPE FLOW INITIATE FOG. LIFR LIKELY AT KLBF AND KVTN AND REALLY
ALONG AND EAST OF HIGHWAY 83 INTO THE MORNING HOURS. ONCE FOG/LOW
CLOUDS BURN OFF MID MORNING WILL LIKELY SEE SCT-BKN CU FIELD
DEVELOP...BUT NO MENTION OF SHRA/TSRA AT THIS TIME.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JWS
SYNOPSIS...KNUTSVIG
SHORT TERM...KNUTSVIG
LONG TERM...CLB
AVIATION...JWS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
354 PM CDT WED AUG 14 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 330 PM CDT WED AUG 14 2013
CLOUDS LINGERED ACROSS MUCH OF THE AREA THIS AFTERNOON AND HAS SO
FAR HELPED TO PUT A CAP ON MORE WIDESPREAD CONVECTION. THAT
SAID...INSTABILITY IS BEGINNING TO BUILD...AND WITH SOME NOTABLE
MOISTURE CONVERGENCE AHEAD OF DEVELOPING CONVECTION TO OUR
NORTH...EXPECT THE POTENTIAL FOR ADDITIONAL DEVELOPMENT THROUGH
THE LATE AFTERNOON AND EVENING HOURS. MODELS HAVE NOT HAD A GREAT
HANDLE ON THIS ALL DAY...ALBEIT 12Z WRF AND LATEST HRRR BOTH
ATTEMPTED TO PICK UP ON CONVECTION TO OUR NORTH...TAKING IT
SOUTHWARD THROUGH THE EVENING HOURS. WHILE CONFIDENCE IS NOT
PARTICULARLY HIGH...CONTINUE TO SEE THE POTENTIAL FOR SOME
ADDITIONAL THUNDERSTORM ACTIVITY THROUGH THE EVENING AND INTO THE
OVERNIGHT HOURS AS THERE IS PLENTY OF INSTABILITY TO
TAP...ESPECIALLY WEST OF HIGHWAY 281. THAT SAID...SHEAR IS VERY
WEAK...AND ANY ADDITIONAL STORMS THAT DO DEVELOP ARE NOT EXPECTED
TO BE SEVERE OR WIDESPREAD.
AS WE WORK TOWARDS THURSDAY MORNING AND FOCUS OF INITIAL
CONVECTION SHIFTS SOUTHWARD...COULD SEE SOME PARTIAL
CLEARING...AND WITH LIGHT SOUTHEASTERLY WINDS AND ELEVATED LOW
LEVEL MOISTURE...DECIDED TO INSERT PATCHY FOG INTO THE FORECAST
FOR THE EARLY MORNING HOURS TOMORROW. LATEST HRRR IS INDICATING
POSSIBLY SOME DENSE FOG ACROSS OUR NORTH BY 09Z...BUT WITH
UNCERTAINTY IN TIMING AND AMOUNT OF CLEARING...PATCHY MENTION
SEEMED MORE REASONABLE FOR THE TIME BEING.
AS WE WORK INTO THE DAYTIME HOURS THURSDAY...THE POTENTIAL FOR
SOME STRONG/MARGINALLY SEVERE STORMS WILL BE REALIZED BY EARLY
AFTERNOON AS MODELS ARE PICKING UP ON AN UPPER LEVEL SHORTWAVE
DROPPING DOWN FROM THE NORTH COUPLED WITH THE PRESENCE OF A WEAK
WARM FRONTAL BOUNDARY DRAPED ACROSS THE LOCAL AREA FROM NORTHWEST
TO SOUTHEAST. THIS COMBINATION...WITH PLENTY OF AVAILABLE
INSTABILITY...SHOULD MAKE FOR A MORE ACTIVE AFTERNOON AND
EVENING...AND CONTINUED WITH MENTION OF POTENTIAL SEVERE WEATHER
IN HWO THIS AFTERNOON. WHILE SHEAR IS NOT ALL THAT
IMPRESSIVE...CAPE AND FORCING SHOULD BE SUFFICIENT FOR THE
DEVELOPMENT OF A FEW STORMS WITH MARGINALLY SEVERE HAIL AND
THUNDERSTORM WIND GUSTS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 PM CDT WED AUG 14 2013
THURSDAY NIGHT THROUGH WEDNESDAY. MAIN FORECAST
CONCERNS WILL BE CHANCES FOR THUNDERSTORMS ON AND OFF THROUGH THE
PERIOD AND TEMPERATURES.
AN UPPER LEVEL WAVE WILL CONTINUE TO MOVE THROUGH THE AREA THURSDAY
NIGHT. THUNDERSTORMS WILL CONTINUE ACROSS THE AREA DURING THE
EVENING BUT GRADUALLY COME TO AN END FROM NORTHWEST TO SOUTHEAST
DURING THE OVERNIGHT HOURS AND INTO FRIDAY MORNING. MUCAPE REMAINS
AROUND 3000 J/KG DURING THE EVENING BUT DROPS OFF LATER IN THE
NIGHT. ON FRIDAY THE UPPER LEVEL RIDGE IN THE ROCKIES STARTS TO
SLIDE TO THE EAST AND WITH THE RAIN MOVING OUT...TEMPERATURES WILL
WARM SOME.
FRIDAY NIGHT INTO SUNDAY THE UPPER LEVEL RIDGE BUILDS ACROSS THE
AREA AND EXPECT DRY CONDITIONS AND TEMPERATURES WILL CONTINUE TO
WARM A FEW DEGREES.
AN UPPER LEVEL WAVE WILL MOVE OVER THE RIDGE SUNDAY NIGHT AND BRING
A SMALL CHANCE FOR THUNDERSTORMS. THERE SHOULD BE A BRIEF BREAK FROM
THUNDERSTORMS AGAIN ON MONDAY BUT ANOTHER UPPER LEVEL WAVE MOVES
INTO THE AREA MONDAY NIGHT AND TUESDAY. THERE IS ALSO A WEAK COLD
FRONT THAT MOVES THROUGH THE FORECAST AREA MONDAY NIGHT.
THUNDERSTORMS ARE EXPECTED ALONG AND BEHIND THE COLD FRONT. DESPITE
THE COLD FRONT TEMPERATURES SHOULD CONTINUE TO WARM A DEGREE OR TWO
EACH DAY AS THE UPPER RIDGE SETTLES OVER THE PLAINS.
TUESDAY NIGHT AND WEDNESDAY THE MODELS HAVE SOME DIFFERENCES IN THE
MAIN PATTERN. THE GFS HAS AN UPPER RIDGE...WHILE THE ECMWF HAS A
TROUGH MOVING THROUGH. WILL HAVE A SMALL CHANCE FOR THUNDERSTORMS
FOR NOW. THE TEMPERATURE SHOULD REMAIN ABOVE NORMAL.
&&
.AVIATION...(FOR THE 18Z KGRI TAF THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1235 PM CDT WED AUG 14 2013
PREVAILING VFR CONDS ARE EXPECTED AT KGRI THROUGH THE AFTERNOON
HOURS AS PLENTY OF MID LEVEL CLOUD COVER CONTINUES TO STREAM
ACROSS THE REGION. WILL LIKELY SEE SOME BREAKS IN THIS CLOUD COVER
FROM TIME TO TIME...WHICH COULD ALLOW INSTABILITY TO BUILD...AND
KEPT MENTION OF A VCTS AFT 15/00Z AS A BAND OF SHOWERS AND
THUNDERSTORMS COULD DEVELOP IN RESPONSE TO THIS BUILDING
INSTABILITY AND FORCING FROM A WEAK APPROACHING SHORT WAVE.
OTHERWISE...STILL EXPECT SKIES TO CLEAR SOMEWHAT DURING THE LATE
OVERNIGHT HOURS...AND THIS CLEARING COMBINED WITH LIGHT
SOUTHEASTERLY WINDS AND SATURATED LOW LEVELS...COULD RESULT IN
SOME MVFR OR LOWER VSBYS AND CIGS TOWARDS DAY BREAK. ANY FOG THAT
DOES DEVELOP...HOWEVER...IS EXPECTED TO BE SHORT LIVED...AND A
RETURN TO VFR CONDITIONS IS EXPECTED AFT 15/13Z.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...SAR
LONG TERM...JCB
AVIATION...SAR
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1243 PM CDT WED AUG 14 2013
.UPDATE...
ISSUED AT 1021 AM CDT WED AUG 14 2013
MADE A FEW CHANGES TO POP/WX/SKY AND ALSO TEMPS IN THE NORTHEAST
FOR TODAY. LATEST TRENDS SHOW REMNANTS FROM THE OVERNIGHT MCS
STILL LINGERING IN THE NORTHEAST. THIS LOOKS TO BE A FAVORABLE
AREA FOR SHOWERS TO CONTINUE INTO THE EARLY AFTERNOON HOURS AS
INDICATED BY THE 12Z NAM...ALTHOUGH THE NAM IS A BIT SLOW. THIS
AFTERNOON... THUNDERSTORM CHANCES GET A LITTLE MORE NEBULOUS AS
NAM POINTS TOWARD ACTIVITY CONTINUING IN THE NORTHEAST...AND ONLY
FAVORS ISOLATED ACTIVITY IN THE FAR WEST. THE 06Z GFS KEEPS THE
WHOLE EASTERN CWA ACTIVE...AS DOES THE 09Z SREF. MADE SLIGHT
ADJUSTMENTS BASED ON LATEST TRENDS...BUT WILL CONTINUE TO EVALUATE
12Z MODEL SUITE AND EFFECTS OF MORNING CONVECTION BEFORE MAKING
MAJOR CHANGES FOR THIS AFTERNOON. WILL ALSO MONITOR FOR SEVERE
THREAT AS SHEAR LOOKS A LITTLE BETTER THAN YESTERDAY ACROSS THE
AREA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 320 AM CDT WED AUG 14 2013
IN THE VERY NEAR TERM MESOSCALE CONVECTIVE VORTICITY (MCV) MOVING
ACROSS NORTHERN NEBRASKA. HRRR MODEL WANTS TO DEVELOP MORE
CONVECTION INTO SOUTHWEST NEBRASKA THROUGH THE EARLY MORNING BUT
RADAR TRENDS SHOWING THAT FORCING DIMINISHING OVER SOUTHWEST
NEBRASKA. HAVE CONTINUED LIKELY POPS OVER NORTH CENTRAL NEBRASKA
WITH CHANCES SLOWLY TAPERING DOWN TO SLIGHT CHANCE AS THE SYSTEM
MOVES EAST. CHANCE POPS BROUGHT BACK INTO ENTIRE FORECAST AREA
THIS AFTERNOON AS A WAVE MOVES SOUTHEAST ACROSS FORECAST AREA FROM
SOUTH DAKOTA. TEMPERATURES TODAY WILL BE SKEWED BY MCV AND CLOUD
SHIELD OVER NORTH CENTRAL NEBRASKA WITH HIGH AT ONEILL 74 DEGREES.
80S TO THE WEST AND SOUTHWEST WHERE PARTLY TO MOSTLY CLOUDY SKIES
SEEN. FAIRLY ROBUST SOUTHERLY FLOW THIS AFTERNOON WITH DEW POINTS
AROUND 60. TIMING OF WAVES WILL BE KEY TO PRECIPITATION CHANCES.
LOW LEVEL JET TONIGHT WILL HELP TO SUSTAIN CONVECTION FROM THE
AFTERNOON AND HELP TO CARRY IT ACROSS THE FORECAST AREA. COOLER
TEMPERATURES AGAIN WITH LOWS BY SUNRISE IN THE MID TO UPPER 50S.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 320 AM CDT WED AUG 14 2013
A SHORTWAVE TROUGH WILL ROTATE SOUTHEAST ACROSS THE AREA THURSDAY
ON THE EASTERN PERIPHERY OF THE ROCKIES UPPER LEVEL RIDGE.
SCATTERED AFTERNOON THUNDERSTORMS ARE POSSIBLE AS THIS FEATURE
ROTATES SOUTHEAST ACROSS THE AREA. STEEP LOW AND MID LEVEL LAPSE
RATES COMBINED WITH AMPLE MOISTURE...SHOULD YIELD MODERATE TO
LOCALLY STRONG INSTABILITY BY AFTERNOON. NORTHWEST FLOW ALOFT WILL
INCREASE...AND WHEN COMBINED WITH WEAK EAST TO SOUTHEAST FLOW AT
THE SURFACE...DECENT BULK SHEAR OF 35 TO 45 KTS WILL LIKELY
SUPPORT A FEW SOUTHEAST MOVING SUPERCELLS WITH THE POTENTIAL FOR
LARGE HAIL.
AFTER THURSDAY...THE UPPER LEVEL RIDGE WILL AMPLIFY AND BUILD
NORTHEAST OVER THE AREA...BRINGING A SPELL OF DRY WEATHER FRIDAY
THROUGH SUNDAY. TEMPERATURES WILL SLOWLY WARM DURING THIS
PERIOD...WITH HIGHS RANGING FROM THE LOWER TO MID 80S FRIDAY...TO
THE MID AND UPPER 80S SUNDAY.
EARLY NEXT WEEK THE UPPER LEVEL RIDGE REMAINS ANCHORED OVER THE
AREA. MODELS ARE TRYING TO BRING A DISTURBANCE THROUGH THE REGION
ON THE SOUTHERN FRINGES OF THE NORTHERN STREAM. CONFIDENCE IS LOW
AT THIS POINT REGARDING THE TIMING AND STRENGTH OF THIS
DISTURBANCE. HAVE KEPT ANY CHANCES FOR PRECIPITATION LOW...AND
HAVE KEPT TEMPERATURES WARM WITH THE UPPER LEVEL RIDGE IN CONTROL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1243 PM CDT WED AUG 14 2013
FORECAST FOR THE TAF SITES INCLUDES LINGERING MVFR CIGS LIFTING TO
VFR THIS THIS AFTERNOON. KLBF AND KVTN CIGS SHOULD BE LIFTING EARLY
IN THE AFTERNOON. SOME VFR CUMULUS WILL LIKELY BE DEVELOPING BY
MID AFTERNOON...WITH POSSIBLY SOME THUNDERSTORM ACTIVITY IN THE
REGION. CONFIDENCE IS RATHER LOW TO PUT IN THE TAF AT THIS TIME.
TONIGHT...MODELS HAVE INDICATED LOW LEVEL MOISTURE WILL BE IN
PLACE FOR LIGHT FOG/MIST LATE TONIGHT. HOWEVER...SOME INCREASING
CLOUDS FROM THE NORTHWEST MAY INHIBIT DEVELOPMENT LATE IN THE
NIGHT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KNUTSVIG
SHORT TERM...POWER
LONG TERM...TAYLOR
AVIATION...KNUTSVIG
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1021 AM CDT WED AUG 14 2013
.UPDATE...
ISSUED AT 1021 AM CDT WED AUG 14 2013
MADE A FEW CHANGES TO POP/WX/SKY AND ALSO TEMPS IN THE NORTHEAST
FOR TODAY. LATEST TRENDS SHOW REMNANTS FROM THE OVERNIGHT MCS
STILL LINGERING IN THE NORTHEAST. THIS LOOKS TO BE A FAVORABLE
AREA FOR SHOWERS TO CONTINUE INTO THE EARLY AFTERNOON HOURS AS
INDICATED BY THE 12Z NAM...ALTHOUGH THE NAM IS A BIT SLOW. THIS
AFTERNOON... THUNDERSTORM CHANCES GET A LITTLE MORE NEBULOUS AS
NAM POINTS TOWARD ACTIVITY CONTINUING IN THE NORTHEAST...AND ONLY
FAVORS ISOLATED ACTIVITY IN THE FAR WEST. THE 06Z GFS KEEPS THE
WHOLE EASTERN CWA ACTIVE...AS DOES THE 09Z SREF. MADE SLIGHT
ADJUSTMENTS BASED ON LATEST TRENDS...BUT WILL CONTINUE TO EVALUATE
12Z MODEL SUITE AND EFFECTS OF MORNING CONVECTION BEFORE MAKING
MAJOR CHANGES FOR THIS AFTERNOON. WILL ALSO MONITOR FOR SEVERE
THREAT AS SHEAR LOOKS A LITTLE BETTER THAN YESTERDAY ACROSS THE
AREA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 320 AM CDT WED AUG 14 2013
IN THE VERY NEAR TERM MESOSCALE CONVECTIVE VORTICITY (MCV) MOVING
ACROSS NORTHERN NEBRASKA. HRRR MODEL WANTS TO DEVELOP MORE
CONVECTION INTO SOUTHWEST NEBRASKA THROUGH THE EARLY MORNING BUT
RADAR TRENDS SHOWING THAT FORCING DIMINISHING OVER SOUTHWEST
NEBRASKA. HAVE CONTINUED LIKELY POPS OVER NORTH CENTRAL NEBRASKA
WITH CHANCES SLOWLY TAPERING DOWN TO SLIGHT CHANCE AS THE SYSTEM
MOVES EAST. CHANCE POPS BROUGHT BACK INTO ENTIRE FORECAST AREA
THIS AFTERNOON AS A WAVE MOVES SOUTHEAST ACROSS FORECAST AREA FROM
SOUTH DAKOTA. TEMPERATURES TODAY WILL BE SKEWED BY MCV AND CLOUD
SHIELD OVER NORTH CENTRAL NEBRASKA WITH HIGH AT ONEILL 74 DEGREES.
80S TO THE WEST AND SOUTHWEST WHERE PARTLY TO MOSTLY CLOUDY SKIES
SEEN. FAIRLY ROBUST SOUTHERLY FLOW THIS AFTERNOON WITH DEW POINTS
AROUND 60. TIMING OF WAVES WILL BE KEY TO PRECIPITATION CHANCES.
LOW LEVEL JET TONIGHT WILL HELP TO SUSTAIN CONVECTION FROM THE
AFTERNOON AND HELP TO CARRY IT ACROSS THE FORECAST AREA. COOLER
TEMPERATURES AGAIN WITH LOWS BY SUNRISE IN THE MID TO UPPER 50S.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 320 AM CDT WED AUG 14 2013
A SHORTWAVE TROUGH WILL ROTATE SOUTHEAST ACROSS THE AREA THURSDAY
ON THE EASTERN PERIPHERY OF THE ROCKIES UPPER LEVEL RIDGE.
SCATTERED AFTERNOON THUNDERSTORMS ARE POSSIBLE AS THIS FEATURE
ROTATES SOUTHEAST ACROSS THE AREA. STEEP LOW AND MID LEVEL LAPSE
RATES COMBINED WITH AMPLE MOISTURE...SHOULD YIELD MODERATE TO
LOCALLY STRONG INSTABILITY BY AFTERNOON. NORTHWEST FLOW ALOFT WILL
INCREASE...AND WHEN COMBINED WITH WEAK EAST TO SOUTHEAST FLOW AT
THE SURFACE...DECENT BULK SHEAR OF 35 TO 45 KTS WILL LIKELY
SUPPORT A FEW SOUTHEAST MOVING SUPERCELLS WITH THE POTENTIAL FOR
LARGE HAIL.
AFTER THURSDAY...THE UPPER LEVEL RIDGE WILL AMPLIFY AND BUILD
NORTHEAST OVER THE AREA...BRINGING A SPELL OF DRY WEATHER FRIDAY
THROUGH SUNDAY. TEMPERATURES WILL SLOWLY WARM DURING THIS
PERIOD...WITH HIGHS RANGING FROM THE LOWER TO MID 80S FRIDAY...TO
THE MID AND UPPER 80S SUNDAY.
EARLY NEXT WEEK THE UPPER LEVEL RIDGE REMAINS ANCHORED OVER THE
AREA. MODELS ARE TRYING TO BRING A DISTURBANCE THROUGH THE REGION
ON THE SOUTHERN FRINGES OF THE NORTHERN STREAM. CONFIDENCE IS LOW
AT THIS POINT REGARDING THE TIMING AND STRENGTH OF THIS
DISTURBANCE. HAVE KEPT ANY CHANCES FOR PRECIPITATION LOW...AND
HAVE KEPT TEMPERATURES WARM WITH THE UPPER LEVEL RIDGE IN CONTROL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 655 AM CDT WED AUG 14 2013
SOME MVFR (CEILINGS) STRATUS OVER WESTERN NEBRASKA WILL LINGER
THROUGH MID MORNING BEFORE LIFTING. THUNDERSTORMS KANW TO KONL TO
KBBW WILL CONTINUE TO MOVE EAST INTO EASTERN NEBRASKA THROUGH THE
MORNING. DRIER AIR WILL ADVECT INTO WESTERN NEBRASKA THIS
AFTERNOON AND EVENING. THUNDERSTORM CHANCES INCREASE ACROSS
WESTERN NEBRASKA THIS AFTERNOON AND EVENING WITH GENERALLY VFR
CONDITIONS PREVAILING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KNUTSVIG
SHORT TERM...POWER
LONG TERM...TAYLOR
AVIATION...POWER
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
655 AM CDT WED AUG 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 320 AM CDT WED AUG 14 2013
IN THE VERY NEAR TERM MESOSCALE CONVECTIVE VORTICITY (MCV) MOVING
ACROSS NORTHERN NEBRASKA. HRRR MODEL WANTS TO DEVELOP MORE
CONVECTION INTO SOUTHWEST NEBRASKA THROUGH THE EARLY MORNING BUT
RADAR TRENDS SHOWING THAT FORCING DIMINISHING OVER SOUTHWEST
NEBRASKA. HAVE CONTINUED LIKELY POPS OVER NORTH CENTRAL NEBRASKA
WITH CHANCES SLOWLY TAPERING DOWN TO SLIGHT CHANCE AS THE SYSTEM
MOVES EAST. CHANCE POPS BROUGHT BACK INTO ENTIRE FORECAST AREA
THIS AFTERNOON AS A WAVE MOVES SOUTHEAST ACROSS FORECAST AREA FROM
SOUTH DAKOTA. TEMPERATURES TODAY WILL BE SKEWED BY MCV AND CLOUD
SHIELD OVER NORTH CENTRAL NEBRASKA WITH HIGH AT ONEILL 74 DEGREES.
80S TO THE WEST AND SOUTHWEST WHERE PARTLY TO MOSTLY CLOUDY SKIES
SEEN. FAIRLY ROBUST SOUTHERLY FLOW THIS AFTERNOON WITH DEW POINTS
AROUND 60. TIMING OF WAVES WILL BE KEY TO PRECIPITATION CHANCES.
LOW LEVEL JET TONIGHT WILL HELP TO SUSTAIN CONVECTION FROM THE
AFTERNOON AND HELP TO CARRY IT ACROSS THE FORECAST AREA. COOLER
TEMPERATURES AGAIN WITH LOWS BY SUNRISE IN THE MID TO UPPER 50S.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 320 AM CDT WED AUG 14 2013
A SHORTWAVE TROUGH WILL ROTATE SOUTHEAST ACROSS THE AREA THURSDAY
ON THE EASTERN PERIPHERY OF THE ROCKIES UPPER LEVEL RIDGE.
SCATTERED AFTERNOON THUNDERSTORMS ARE POSSIBLE AS THIS FEATURE
ROTATES SOUTHEAST ACROSS THE AREA. STEEP LOW AND MID LEVEL LAPSE
RATES COMBINED WITH AMPLE MOISTURE...SHOULD YIELD MODERATE TO
LOCALLY STRONG INSTABILITY BY AFTERNOON. NORTHWEST FLOW ALOFT WILL
INCREASE...AND WHEN COMBINED WITH WEAK EAST TO SOUTHEAST FLOW AT
THE SURFACE...DECENT BULK SHEAR OF 35 TO 45 KTS WILL LIKELY
SUPPORT A FEW SOUTHEAST MOVING SUPERCELLS WITH THE POTENTIAL FOR
LARGE HAIL.
AFTER THURSDAY...THE UPPER LEVEL RIDGE WILL AMPLIFY AND BUILD
NORTHEAST OVER THE AREA...BRINGING A SPELL OF DRY WEATHER FRIDAY
THROUGH SUNDAY. TEMPERATURES WILL SLOWLY WARM DURING THIS
PERIOD...WITH HIGHS RANGING FROM THE LOWER TO MID 80S FRIDAY...TO
THE MID AND UPPER 80S SUNDAY.
EARLY NEXT WEEK THE UPPER LEVEL RIDGE REMAINS ANCHORED OVER THE
AREA. MODELS ARE TRYING TO BRING A DISTURBANCE THROUGH THE REGION
ON THE SOUTHERN FRINGES OF THE NORTHERN STREAM. CONFIDENCE IS LOW
AT THIS POINT REGARDING THE TIMING AND STRENGTH OF THIS
DISTURBANCE. HAVE KEPT ANY CHANCES FOR PRECIPITATION LOW...AND
HAVE KEPT TEMPERATURES WARM WITH THE UPPER LEVEL RIDGE IN CONTROL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 655 AM CDT WED AUG 14 2013
SOME MVFR (CEILINGS) STRATUS OVER WESTERN NEBRASKA WILL LINGER
THROUGH MID MORNING BEFORE LIFTING. THUNDERSTORMS KANW TO KONL TO
KBBW WILL CONTINUE TO MOVE EAST INTO EASTERN NEBRASKA THROUGH THE
MORNING. DRIER AIR WILL ADVECT INTO WESTERN NEBRASKA THIS
AFTERNOON AND EVENING. THUNDERSTORM CHANCES INCREASE ACROSS
WESTERN NEBRASKA THIS AFTERNOON AND EVENING WITH GENERALLY VFR
CONDITIONS PREVAILING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...POWER
LONG TERM...TAYLOR
AVIATION...POWER
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
348 AM CDT WED AUG 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 320 AM CDT WED AUG 14 2013
IN THE VERY NEAR TERM MESOSCALE CONVECTIVE VORTICITY (MCV) MOVING
ACROSS NORTHERN NEBRASKA. HRRR MODEL WANTS TO DEVELOP MORE
CONVECTION INTO SOUTHWEST NEBRASKA THROUGH THE EARLY MORNING BUT
RADAR TRENDS SHOWING THAT FORCING DIMINISHING OVER SOUTHWEST
NEBRASKA. HAVE CONTINUED LIKELY POPS OVER NORTH CENTRAL NEBRASKA
WITH CHANCES SLOWLY TAPERING DOWN TO SLIGHT CHANCE AS THE SYSTEM
MOVES EAST. CHANCE POPS BROUGHT BACK INTO ENTIRE FORECAST AREA
THIS AFTERNOON AS A WAVE MOVES SOUTHEAST ACROSS FORECAST AREA FROM
SOUTH DAKOTA. TEMPERATURES TODAY WILL BE SKEWED BY MCV AND CLOUD
SHIELD OVER NORTH CENTRAL NEBRASKA WITH HIGH AT ONEILL 74 DEGREES.
80S TO THE WEST AND SOUTHWEST WHERE PARTLY TO MOSTLY CLOUDY SKIES
SEEN. FAIRLY ROBUST SOUTHERLY FLOW THIS AFTERNOON WITH DEW POINTS
AROUND 60. TIMING OF WAVES WILL BE KEY TO PRECIPITATION CHANCES.
LOW LEVEL JET TONIGHT WILL HELP TO SUSTAIN CONVECTION FROM THE
AFTERNOON AND HELP TO CARRY IT ACROSS THE FORECAST AREA. COOLER
TEMPERATURES AGAIN WITH LOWS BY SUNRISE IN THE MID TO UPPER 50S.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 320 AM CDT WED AUG 14 2013
A SHORTWAVE TROUGH WILL ROTATE SOUTHEAST ACROSS THE AREA THURSDAY
ON THE EASTERN PERIPHERY OF THE ROCKIES UPPER LEVEL RIDGE.
SCATTERED AFTERNOON THUNDERSTORMS ARE POSSIBLE AS THIS FEATURE
ROTATES SOUTHEAST ACROSS THE AREA. STEEP LOW AND MID LEVEL LAPSE
RATES COMBINED WITH AMPLE MOISTURE...SHOULD YIELD MODERATE TO
LOCALLY STRONG INSTABILITY BY AFTERNOON. NORTHWEST FLOW ALOFT WILL
INCREASE...AND WHEN COMBINED WITH WEAK EAST TO SOUTHEAST FLOW AT
THE SURFACE...DECENT BULK SHEAR OF 35 TO 45 KTS WILL LIKELY
SUPPORT A FEW SOUTHEAST MOVING SUPERCELLS WITH THE POTENTIAL FOR
LARGE HAIL.
AFTER THURSDAY...THE UPPER LEVEL RIDGE WILL AMPLIFY AND BUILD
NORTHEAST OVER THE AREA...BRINGING A SPELL OF DRY WEATHER FRIDAY
THROUGH SUNDAY. TEMPERATURES WILL SLOWLY WARM DURING THIS
PERIOD...WITH HIGHS RANGING FROM THE LOWER TO MID 80S FRIDAY...TO
THE MID AND UPPER 80S SUNDAY.
EARLY NEXT WEEK THE UPPER LEVEL RIDGE REMAINS ANCHORED OVER THE
AREA. MODELS ARE TRYING TO BRING A DISTURBANCE THROUGH THE REGION
ON THE SOUTHERN FRINGES OF THE NORTHERN STREAM. CONFIDENCE IS LOW
AT THIS POINT REGARDING THE TIMING AND STRENGTH OF THIS
DISTURBANCE. HAVE KEPT ANY CHANCES FOR PRECIPITATION LOW...AND
HAVE KEPT TEMPERATURES WARM WITH THE UPPER LEVEL RIDGE IN CONTROL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 120 AM CDT WED AUG 14 2013
CONVECTIVE CLUSTER AND ASSOCIATED MCV WILL MOVE ACROSS SOUTHERN SD
AND NORTHERN NE...AND POSSIBLY INTO THE SANDHILLS THROUGH THE NIGHT.
SCT TSRA HAS BEEN INCLUDED IN THE KVTN TAF THROUGH 08Z. AFTER THE
COMPLEX MOVES THROUGH THERE WILL LIKELY BE SOME STRATUS TWD SUNRISE
AS SUGGESTED BY BUFR SOUNDINGS. EARLIER GUIDANCE ALSO SUGGESTED SOME
POSSIBILITY OF BR FOR KVTN BUT LATEST GUIDANCE DOES NOT. CONFIDENCE
NOT HIGH EITHER WAY SO SINCE IT WAS INCLUDED IN EARLIER KVTN TAFS
HAS OPTED TO KEEP IT IN. FURTHER SOUTH...LATEST HRRR SUGGESTS
CONVECTIVE CLUSTER WILL EVENTUALLY PROPAGATE SOUTH AS LOW LEVEL JET
DEVELOPS. HOWEVER...AREA VWP NOT SHOWING THE DEGREE OF LLJ AS
EARLIER PROGGED AND AS SUCH THERE HAS NOT BEEN AS MUCH SWD
PROGRESSION OF THE MCS YET. HOWEVER...RAP 300K MOISTURE TRANSPORT
VECTOR ARE BEGINNING TO SHOW A SLIGHT INCREASE IN THE LAST HOUR OR
SO. CONFIDENCE NOT HIGH FOR THE COMPLEX TO HOLD TOGETHER UNTIL
13-14Z TIME FRAME AS HRRR SUGGESTS FOR KLBF TAF. THEREFORE WILL HOLD
OFF ON INCLUDING IT FOR NOW. AS FOR THE STRATUS/FOG
POTENTIAL...LATEST GUIDANCE HAS GONE AWAY FROM IFR OR LOWER CIGS AND
VSBYS REMAINING ABOVE 5SM IN BR. WILL TREND THE FORECAST IN THIS
DIRECTION FOR KLBF...AND WILL HOLD CIGS IN THE MVFR CAT. VSBY ALREADY
STARTING TO GO DOWN AT KLBF BUT WILL ALSO HAVE TO SEE WHAT EFFECT
OUTFLOW BOUNDARY HAS ON LOCAL VSBY.
NEXT FCST PROBLEM CONCERNS CONVECTIVE REDEVELOPMENT PRIOR TO 14.21Z.
BELIEVE THE SHORT RANGE MODELS ARE HAVING A TOUGH TIME
DIFFERENTIATING BETWEEN SIGNIFICANT UPPER PV ANOMALIES TO BE ABLE TO
RESOLVE THE DEGREE OF LOW LEVEL CONVERGENCE TO SUPPORT DEEP MOIST
CONVECTION. LAST FEW DAYS HAS SHOWN CONVECTION ALLOWING MODELS TO
PERFORM BETTER WITH THE IDEA OF DEVELOPMENT...WHICH MEANS CONFIDENCE
IN TSRA DEVELOPMENT BEYOND 6 HRS IS LOW. WILL SIDE WITH AN AFTERNOON
REDEVELOPMENT...WHICH WOULD BE MORE CLIMATOLOGICAL LY VIABLE...VIA A
PROB30 GROUP.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...POWER
LONG TERM...TAYLOR
AVIATION...JWS
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
119 AM CDT WED AUG 14 2013
.SYNOPSIS...
ISSUED AT 242 PM CDT TUE AUG 13 2013
A THUNDERSTORM COMPLEX FROM THIS MORNING LEFT A WEAK OUTFLOW
BOUNDARY ACROSS WEST-CENTRAL NEBRASKA...WHERE A FEW THUNDERSTORMS
HAVE INITIATED OVER THE PAST HOUR. A WEAK UPPER LEVEL DISTURBANCE
EXISTS ACROSS THE DAKOTAS IN NORTHWEST FLOW ALOFT...WITH UPPER
RIDGING OVER THE INTERMOUNTAIN WEST AND AN UPPER TROUGH OVER THE
GREAT LAKES REGION.
&&
.UPDATE...
ISSUED AT 120 AM CDT WED AUG 14 2013
UPDATED FORECAST TO ACCOUNT FOR MCV MOVING ACROSS NORTHERN
NEBRASKA. UPDATED POPS AND QPF TO ACCOUNT FOR HEAVY PRECIPITATION
WITH COMPLEX...RADAR ESTIMATED.
UPDATE ISSUED AT 856 PM CDT TUE AUG 13 2013
QUICK UPDATE TO FINE TUNE PRECIPITATION CHANCES ACROSS THE AREA.
THUNDERSTORMS OVER THE SOUTHWEST HAVE DECREASED...BUT THE MCS
MOVING INTO NEBRASKA FROM SOUTH DAKOTA IS HOLDING TOGETHER WELL.
SHORT RANGE MODELS SUGGEST SOME POTENTIAL FOR MCS MAINTENANCE
THROUGH THE NEXT FEW HOURS...THOUGH MID LEVEL LAPSE RATES ARE NOT
STELLAR. GOOD POTENTIAL FOR THE NORTHERN MOST COUNTIES THOUGH FOR
THE NEXT FEW HOURS. OTHERWISE REST OF FORECAST LOOKS GOOD.
UPDATE ISSUED AT 643 PM CDT TUE AUG 13 2013
ADJUSTED PRECIPITATION CHANCES ACROSS SOUTHWEST NEBRASKA...ALONG
WITH CLOUD COVER. MOVEMENT OF THE STORMS IS VERY SLOWLY SOUTHWEST
THOUGH STORM INTERACTION HAS CAUSED VARIABLE MOVEMENT OF THE
STRONGEST UPDRAFTS. OTHERWISE REST OF FORECAST LOOKS ON TRACK.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 242 PM CDT TUE AUG 13 2013
THUNDERSTORM ACTIVITY WILL INCREASE THROUGH THE LATE AFTERNOON
HOURS ACROSS THE AREA. ACTIVITY IS CURRENTLY GETTING STARTED
ACROSS THE WEST WHERE THE BOUNDARY FROM THE MORNINGS THUNDERSTORMS
EXISTS. CAPE RUNS AROUND 1500 J/KG CURRENTLY...BUT 0-6 KM SHEAR
WEAK AT UNDER 30 KTS. A FEW STRONG STORMS WILL BE POSSIBLE...BUT
EXPECT SEVERE THREAT TO BE LIMITED DUE TO LACKING SHEAR. STEERING
WINDS WILL BE RATHER WEAK...RAISING THE RISK FOR LOCALIZED
FLOODING FROM THUNDERSTORMS TODAY. A LOW LEVEL JET WILL FAVOR
THUNDERSTORM ACTIVITY AFTER MIDNIGHT ACROSS THE NORTH AND
NORTHEAST. ALSO...LOW STRATUS AND FOG WILL BE POSSIBLE TONIGHT
BASED ON BUFR SOUNDINGS AND MOS GUIDANCE. THE MODIFIED RICHARDSON
NUMBER LOOKS TO FAVOR STRATUS MORE THAN FOG... DUE TO THE MIXING
IN THE LOWEST 100 MB. HAVE INCLUDED ONLY PATCHY FOG IN THE SOUTH
FOR LATE TONIGHT/EARLY TOMORROW MORNING. TOMORROW...AN UPPER LEVEL
WAVE MOVES THROUGH THE AREA WITH FAVORABLE INSTABILITY...BUT WEAK
SHEAR ONCE AGAIN.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 242 PM CDT TUE AUG 13 2013
MID TERM...WEDNESDAY NIGHT THROUGH FRIDAY NIGHT...THUNDERSTORM
CHANCES ARE THE MAIN FORECASTING CHALLENGE AS WE APPROACH THURSDAY
AND THURSDAY NIGHT. FOR WEDNESDAY NIGHT...WITH A WEAK CAP IN
PLACE...CONVECTION IS EXPECTED TO BE ONGOING AT THE BEGINNING OF
THE PERIOD. SCATTERED SHOWERS AND THUNDERSTORMS WILL RIDE
SOUTHEAST OVERNIGHT AS NORTHWESTERLY FLOW IN THE MID LEVELS
CONTINUES. A NICE LOW LEVEL JET WILL DEVELOP ACROSS WESTERN KS
INTO CENTRAL NEBR WEDS NIGHT...WHICH WILL HELP TO SUSTAIN SHOWERS
AND THUNDERSTORMS INTO THE OVERNIGHT HOURS. DECIDED TO CONTINUE
SCATTERED COVERAGE OF PCPN...AS UPPER LEVEL FORCING AND DEEP LAYER
SHEAR REMAINS WEAK OVERNIGHT. FOR THURSDAY...RIDGING ALOFT WILL
BEGIN TO BUILD INTO THE ROCKIES WITH INCREASED MID LEVEL WAA
PUSHING INTO THE CENTRAL PLAINS LATE THURSDAY AND THURSDAY NIGHT.
CAPPING WILL BE WEAK ONCE AGAIN WHICH WILL FACILITATE EARLY
INITIATION THURSDAY AFTERNOON. UNLIKE WEDNESDAY...DEEP LAYER
SHEAR...WILL BE STRONGER...ESPECIALLY OVER CENTRAL AND SOUTHERN
NEBRASKA...WHICH MAY FACILITATE STRONG TO SEVERE THUNDERSTORMS
THURSDAY AFTERNOON/THURSDAY NIGHT. ON FRIDAY...RIDGING WILL BUILD
INTO THE NORTHERN ROCKIES AND HIGH PLAINS SHIFTING THE MID LEVEL
FLOW FROM NORTHWEST TO NORTH...EFFECTIVELY CUTTING OFF ANY MID
LEVEL SUPPORT FOR THUNDERSTORMS FRIDAY AFTERNOON AND FRIDAY NIGHT.
LONG TERM...SATURDAY THROUGH TUESDAY...DRY CONDITIONS WILL CONTINUE
INTO SATURDAY...AS WELL AS MOST OF SUNDAY AS RIDGING BUILDS EAST OF
THE ROCKIES. THE LATEST MEX GUIDANCE INCREASES MAX TEMPS INTO THE
LOWER TO MID 90S FOR SATURDAY AND SUNDAY. TRENDED TEMPS UP FOR BOTH
SATURDAY AND SUNDAY INTO THE UPPER 80S TO NEAR 90. NOT CONVINCED WE
WILL HIT THE LOWER TO MIDDLE 90S GIVEN THE FCST H85 TEMPS AND THE
FACT WE HAVE BEEN WET ACROSS THE FCST AREA OVER THE PAST COUPLE OF
WEEKS. RIDGING WILL BEGIN TO BREAK DOWN LATE SUNDAY AS A TROUGH OF
LOW PRESSURE PUSHES INTO THE WESTERN ROCKIES. AS THIS FEATURE
APPROACHES THE CENTRAL PLAINS SUNDAY NIGHT INTO
MONDAY...THUNDERSTORM CHANCES WILL INCREASE FOR MONDAY INTO TUESDAY.
HIGHS ON MONDAY AND TUESDAY WILL BE IN THE LOWER TO MID 80S THANKS
TO INCREASED MOISTURE AND CLOUD
COVER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 120 AM CDT WED AUG 14 2013
CONVECTIVE CLUSTER AND ASSOCIATED MCV WILL MOVE ACROSS SOUTHERN SD
AND NORTHERN NE...AND POSSIBLY INTO THE SANDHILLS THROUGH THE NIGHT.
SCT TSRA HAS BEEN INCLUDED IN THE KVTN TAF THROUGH 08Z. AFTER THE
COMPLEX MOVES THROUGH THERE WILL LIKELY BE SOME STRATUS TWD SUNRISE
AS SUGGESTED BY BUFR SOUNDINGS. EARLIER GUIDANCE ALSO SUGGESTED SOME
POSSIBILITY OF BR FOR KVTN BUT LATEST GUIDANCE DOES NOT. CONFIDENCE
NOT HIGH EITHER WAY SO SINCE IT WAS INCLUDED IN EARLIER KVTN TAFS
HAS OPTED TO KEEP IT IN. FURTHER SOUTH...LATEST HRRR SUGGESTS
CONVECTIVE CLUSTER WILL EVENTUALLY PROPAGATE SOUTH AS LOW LEVEL JET
DEVELOPS. HOWEVER...AREA VWP NOT SHOWING THE DEGREE OF LLJ AS
EARLIER PROGGED AND AS SUCH THERE HAS NOT BEEN AS MUCH SWD
PROGRESSION OF THE MCS YET. HOWEVER...RAP 300K MOISTURE TRANSPORT
VECTOR ARE BEGINNING TO SHOW A SLIGHT INCREASE IN THE LAST HOUR OR
SO. CONFIDENCE NOT HIGH FOR THE COMPLEX TO HOLD TOGETHER UNTIL
13-14Z TIME FRAME AS HRRR SUGGESTS FOR KLBF TAF. THEREFORE WILL HOLD
OFF ON INCLUDING IT FOR NOW. AS FOR THE STRATUS/FOG
POTENTIAL...LATEST GUIDANCE HAS GONE AWAY FROM IFR OR LOWER CIGS AND
VSBYS REMAINING ABOVE 5SM IN BR. WILL TREND THE FORECAST IN THIS
DIRECTION FOR KLBF...AND WILL HOLD CIGS IN THE MVFR CAT. VSBY ALREADY
STARTING TO GO DOWN AT KLBF BUT WILL ALSO HAVE TO SEE WHAT EFFECT
OUTFLOW BOUNDARY HAS ON LOCAL VSBY.
NEXT FCST PROBLEM CONCERNS CONVECTIVE REDEVELOPMENT PRIOR TO 14.21Z.
BELIEVE THE SHORT RANGE MODELS ARE HAVING A TOUGH TIME
DIFFERENTIATING BETWEEN SIGNIFICANT UPPER PV ANOMALIES TO BE ABLE TO
RESOLVE THE DEGREE OF LOW LEVEL CONVERGENCE TO SUPPORT DEEP MOIST
CONVECTION. LAST FEW DAYS HAS SHOWN CONVECTION ALLOWING MODELS TO
PERFORM BETTER WITH THE IDEA OF DEVELOPMENT...WHICH MEANS CONFIDENCE
IN TSRA DEVELOPMENT BEYOND 6 HRS IS LOW. WILL SIDE WITH AN AFTERNOON
REDEVELOPMENT...WHICH WOULD BE MORE CLIMATOLOGICAL LY VIABLE...VIA A
PROB30 GROUP.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...POWER
SYNOPSIS...KNUTSVIG
SHORT TERM...KNUTSVIG
LONG TERM...CLB
AVIATION...POWER
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1235 AM CDT WED AUG 14 2013
.UPDATE...
ISSUED AT 1235 AM CDT WED AUG 14 2013
ESSENTIALLY NO CHANGES MADE FOR THIS ESTF UPDATE. HOWEVER...WE ARE
MONITORING THE MCS OVER THE SANDHILLS...BTWN VTN AND AIA. WE MAY
BE MAKING SUBSTANTIAL CHANGES LATER THIS MRNG BASED ON RADAR TRENDS.
UPDATE ISSUED AT 934 PM CDT TUE AUG 13 2013
ONGOING CONVECTION CURRENTLY IN SW SOUTH DAKOTA/NW NEB IS PROGGED
TO REACH OUR NORTHERN CWA LATE TONIGHT/TOWARD WEDNESDAY MORNING
AND REORIENTED AND INCREASED POPS FOR WED TO ACCOUNT FOR THIS.
ALSO TONIGHT...INCLUDED PATCHY FOG FOR ALL AREAS WITH LIGHT
EASTERLY LLVL FLOW AND RECENT RAINFALL/MOISTURE. STILL SOME
UNCERTAINTY ON HOW LOW VSBYS WILL DROP AND WILL NEED TO MONITOR
TRENDS.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 400 PM CDT TUE AUG 13 2013
WE HAD A MESOSCALE CONVECTIVE VORTEX (MCV) TRACK ACROSS OUR FORECAST
AREA THIS MORNING INTO THE EARLY AFTERNOON HOURS. THIS BROUGHT
WIDESPREAD RAINFALL TO OUR FORECAST AREA AND HAS WORKED OVER THE
ATMOSPHERE ENOUGH THAT ADDITIONAL PRECIPITATION THIS EVENING INTO
TONIGHT IS UNLIKELY. THE CONVECTION THAT TRACKED THROUGH OUR AREA
HAS NOW PASSED SOUTH INTO CENTRAL KANSAS AND NEW STORMS HAVE ALSO
FORMED TO OUR WEST OVER THE HIGH PLAINS OF WESTERN NEBRASKA.
THE WESTERN NEBRASKA THUNDERSTORMS HAVE FORMED ALONG THE LEADING
EDGE OF THE NEXT SHORTWAVE THAT IS TRACKING SOUTHEAST FROM EASTERN
WYOMING/SOUTHWEST SOUTH DAKOTA INTO WESTERN NEBRASKA. DEEP MOISTURE
CONVERGENCE AND AFTERNOON DESTABILIZATION IS ALSO MAXIMIZED ACROSS
WESTERN NEBRASKA INTO THE BLACK HILLS AND THIS IS WHERE ADDITIONAL
THUNDERSTORMS ARE EXPECTED TO FORM THIS EVENING. THIS IS A WEAKLY
SHEARED ENVIRONMENT AND STORM PROPAGATION WILL GENERALLY BE A SLOW
DRIFT TO THE SOUTH...WHICH SHOULD KEEP THE WESTERN STORMS JUST TO
THE WEST OF OUR FORECAST AREA TONIGHT. THERE IS AN OUTSIDE CHANCE OF
OUR WESTERN ZONES SEEING A PREDAWN SHOWER/THUNDERSTORM SHOULD THE
BLACK HILLS CONVECTION MAKE IT THIS FAR SOUTHEAST. HOWEVER...MOST
FORECAST MODEL DATA KEEPS ALL CONVECTION WEST OF OUR FORECAST AREA
TONIGHT AND THUS WE WILL KEEP ALL ZONES DRY TONIGHT...WHILE KEEPING
AN EYE ON THE WEST FOR THE POSSIBILITY OF NEEDING TO THROW SOME POPS
IN THE FORECAST DEPENDING ON FUTURE RADAR TRENDS.
THERE IS SOME POTENTIAL OF FOG TONIGHT GIVEN THE RECENT WIDESPREAD
RAINFALL. HOWEVER...FORECAST MODELS ARE MIXED ON FOG POTENTIAL WITH
THE HRRR MORE FAVORABLE FOR FOG WHILE THE SREF WOULD NOT GIVE US ANY
FOG. ULTIMATELY FOG WILL LARGELY HINGE ON CLOUD COVER AND SUBSEQUENT
COOLING. HAVE LEFT FOG OUT OF THE FORECAST FOR NOW...BUT SHOULD WE
CLEAR OUT AND REMAIN CLEAR THROUGH MOST OF THE NIGHT...THEN COOLING
MIGHT BE ADEQUATE FOR SOME AREAS OF FOG EARLY WEDNESDAY MORNING.
WEDNESDAY...A SHORT WAVE TROUGH WILL TRACK SOUTHEAST ACROSS WESTERN
NEBRASKA. INSTABILITY AND DEEP LAYER SHEAR WILL BE FAIRLY WEAK TO
MODEST AT BEST AND THUS AM NOT EXPECTING SEVERE WEATHER...BUT CAN
NOT RULE OUT A COUPLE OF STRONG THUNDERSTORMS IN ASSOCIATION WITH
PEAK AFTERNOON HEATING. THE BEST CHANCE OF THUNDERSTORMS WILL BE
ACROSS OUR WESTERN ZONES AND TO THE WEST OF OUR FORECAST AREA IN
ASSOCIATION WITH THE APPROACHING SHORTWAVE. TEMPERATURES WILL REMAIN
COOL FOR AUGUST DUE TO A CONTINUATION OF THE COOL AIRMASS
OVERHEAD...CLOUDS...AND POSSIBLE PRECIPITATION. HIGHS WILL GENERALLY
BE IN THE UPPER 70S TO LOWER 80S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 400 PM CDT TUE AUG 13 2013
THE MAIN HIGHLIGHTS OF THIS 6-DAY PERIOD ARE A CONTINUATION OF
CHALLENGING SHOWER/THUNDERSTORM CHANCES IN THE WED NIGHT THROUGH
FRIDAY TIME FRAME WHICH MIGHT EVEN FEATURE A STRONG-SEVERE STORM
THREAT CENTERED ON THURSDAY...FOLLOWED BY WHAT APPEARS TO BE A
PREDOMINANTLY DRY WEEKEND...AND THEN A RETURN TO VERY UNCERTAIN
RAIN CHANCES IN THE SUNDAY NIGHT-TUESDAY TIME FRAME AS THE PATTERN
CHANGES A BIT. ITS BEEN A TOUGH GO OF IT LATELY TRYING TO
DETERMINE HOW HARD TO HIT...OR BACK OFF...POPS EVEN IN THE FIRST
24 HOURS...SO THESE UNCERTAINTIES CONTINUE TO BE MAGNIFIED EVEN IN
THE DAY 2-3 TIME FRAME. OF HIGHER CONFIDENCE IS THAT A FAIRLY
REMARKABLE RUN OF SUB-90 DEGREE TEMPS WILL CONTINUE...WITH THE
MAJORITY OF THE CWA FORECAST TO TOP OUT IN THE LOW-MID 80S DURING
THIS TIME FRAME...WITH KS ZONES AS USUAL MOST FAVORED TO REACH
UPPER 80S ON A FEW DAYS. AS FOR LOW TEMPS...EVERY NIGHT IS
EXPECTED TO BE FAIRLY SIMILAR AND RATHER UNIFORM ACROSS THE
CWA...EITHER IN THE LOW OR MID 60S.
STARTING OFF WEDNESDAY EVENING/NIGHT...GAVE A BEST-STAB AT TWO
6-HOUR POP BLOCKS HEAVILY BASED ON MET/MAV GUIDANCE BLEND...WITH
THE EVENING PERIOD FEATURING 20S-40S...AND THE LATE NIGHT PERIOD
RANGING FROM ONLY 20S FAR WEST TO 50S IN EASTERN-MOST NEB ZONES.
IN OTHER WORDS...THERE IS A DECENT CHANCE THAT PARTS OF THE CWA
WILL SEE RAIN...BUT CONFIDENCE IN TIMING/PLACEMENT PRECLUDES
LIKELY POPS ANYWHERE YET. ON THE LARGE-SCALE ALOFT...LEGITIMATE
NORTHWEST-FLOW IS IN PLACE OVER THE CENTRAL PLAINS...BETWEEN A
RIDGE AXIS EXTENDING NORTHWARD ACROSS THE ROCKIES FROM NORTHERN
MEXICO INTO SOUTHWEST CANADA...AND A BROAD TROUGH ANCHORED OVER
SOUTHEAST CANADA/THE NORTHEAST CONUS. ON A MORE LOCAL/REGIONAL
LEVEL...THE CWA IS PROGGED TO REMAIN UNDER/NEAR THE MAIN TRACK OF
LOW-AMPLITUDE SHORTWAVE TROUGHS RIPPLING THROUGH THE NORTHWEST
FLOW. STARTING OFF RIGHT AWAY WED EVENING AT 00Z/7PM...ITS
EXPECTED THAT AT LEAST A SMALL PART OF THE CWA SHOULD BE SEEING
ACTIVITY PERSISTING FROM THE LATE AFTERNOON HOURS...ALTHOUGH MODEL
QPF/REFLECTIVITY FIELDS VARY CONSIDERABLY ON THE MOST FAVORED
AREA. AS THE NIGHT WEARS ON...THERE IS A DECENT SIGNAL FOR WARM
AIR ADVECTION/MOISTURE TRANSPORT IN THE 850-700 MILLIBAR
LAYER...WITHIN THE AXIS OF A MODEST 20+KT SOUTHWESTERLY LOW LEVEL
JET. PER THE 12Z/18Z NAM AND LAST FEW SREF RUNS...THIS WOULD FAVOR
EASTERN ZONES FOR THE HIGHEST LATE NIGHT POPS...WHILE THE
ECWMF/GFS WOULD MORE-SO FAVOR CENTRAL/SOUTHWEST ZONES. AS FOR
THUNDERSTORM INTENSITY...ALTHOUGH NOT EXPECTING A WIDESPREAD
NOCTURNAL SEVERE THREAT...CERTAINLY A FEW STRONG TO MARGINALLY
SEVERE STORMS WITH MAINLY A HAIL/LOCALLY HEAVY RAIN THREAT CANNOT
BE RULED OUT GIVEN MUCAPE INCREASING TO AT LEAST 500-1000 J/KG IN
THE PRESENCE OF AROUND 25KT OF DEEP LAYER SHEAR.
THURSDAY/THURSDAY NIGHT...THIS 24 HOURS WOULD APPEAR TO CONTAIN
THE OVERALL-HIGHEST THREAT OF SEVERE STORMS DURING THE NEXT
SEVERAL DAYS...ALTHOUGH THE JURY IS STILL OUT ON WHETHER IT WOULD
BE MORE LOCALIZED OR MORE WIDESPREAD. CERTAINLY WOULD NOT BE
SURPRISED TO SEE THE UPCOMING SPC DAY 2 OUTLOOK INTRODUCE A SLIGHT
RISK FOR ALL/PART OF THE CWA...MAINLY FOR THE AFTERNOON/EVENING
HOURS. IN THE BIG PICTURE...SEASONABLY STRONG/SHARP NORTHWEST FLOW
STRENGTHENS AB IT...AS MODELS ARE IN DECENT AGREEMENT IN DRIVING A
BIT STRONGER/ORGANIZED SHORTWAVE TROUGH SOUTHWARD OUT OF WESTERN
SD ACROSS THE HEART OF CENTRAL NEB/KS. FOR THE MORNING
HOURS...KEPT POPS AT SLIGHT 20S EXCEPT 30S IN THE EAST WHERE
SEEMINGLY THE BEST CHANCE OF LINGERING OVERNIGHT CONVECTION WOULD
BE. THEN HAVE 30 POPS NEARLY ALL AREAS DURING THE AFTERNOON TO
ACCOUNT FOR THUNDERSTORM REDEVELOPMENT AND/OR
RE-INTENSIFICATION...ASSUMING OF COURSE THAT SUFFICIENT HEATING
CAN TAKE PLACE. ITS STILL TOO SOON TO TELL THOUGH WHETHER
POTENTIALLY VIGOROUS AFTERNOON ACTIVITY MAINLY DEVELOPS LOCALLY OR
MOVES IN FROM THE NORTHWEST. AT ANY RATE...THE 18Z NAM DEPICTS A
FAIRLY POTENT NORTHWEST FLOW SEVERE ENVIRONMENT WITH MIXED LAYER
CAPE 2000+ J/KG IN THE PRESENCE OF DECENT 30-40 KNOT DEEP LAYER
SHEAR...MAKING A FEW SUPERCELLS A POSSIBILITY IF THE MESOSCALE
FEATURES COME TOGETHER. FOR THURSDAY EVENING/NIGHT...KEPT 30-50
POPS GOING AREA-WIDE...HIGHEST IN THE FAR SOUTH. NOT ACCOUNTING
FOR POSSIBLE CONVECTIVE EFFECTS...BREEZES DURING THE DAY THURSDAY
ARE EXPECTED TO AVERAGE AROUND 10 MPH FROM THE SOUTH.
FRIDAY/FRIDAY NIGHT...THE LATEST NAM/GFS ARE IN GOOD AGREEMENT
AMPLIFYING THE WESTERN CONUS RIDGE EASTWARD OVER THE CENTRAL
PLAINS...RESULTING IN MODEST HEIGHT RISES AND NEARLY DUE-NORTHERLY
FLOW ALOFT. THIS SHOULD RESULT IN A LESS-FAVORABLE ENVIRONMENT FOR
THUNDERSTORM DEVELOPMENT. HOWEVER...KEPT THE MAJORITY OF THE CWA
WITH SLIGHT POPS DURING THE DAYTIME HOURS MAINLY TO ACCOUNT FOR
POSSIBLE DIURNAL-HEATING INDUCED CONVECTION...BUT LEFT FRIDAY
NIGHT DRY PER PREVIOUS FORECAST.
SATURDAY THROUGH SUNDAY...KEPT THE DRY FORECAST GOING CWA-
WIDE...AS SEEMINGLY-BENIGN NORTHERLY FLOW REMAINS IN PLACE ALOFT
TO THE EAST OF THE ROCKIES-CENTERED RIDGE AXIS. BOTH THE ECWMF/GFS
KEEP THE MAIN BRANCHES OF STRONGER FLOW ALOFT WELL NORTH NEAR THE
CANADIAN BORDER...AND ALSO IN THE SOUTHEAST STATES...WITH THE CWA
ALSO STAYING SAFELY NORTHWEST OF A STALLED...POSSIBLY RETROGRADING
CLOSED MID LEVEL LOW OVER THE SOUTHERN MO/AR AREA ADVERTISED MORE
SO BY THE ECMWF THAN THE GFS. NOT READY TO GUARANTEE A DRY WEEKEND
YET...BUT AT LEAST FOR NOW POPS HAVE BEEN KEPT IN THE SILENT 5-10
RANGE. GIVEN THAT THE AREA HAS SEEN VERY LITTLE IN THE WAY OF NON-
CONVECTIVE BREEZE LATELY...ITS WORTH NOTING THAT THE CURRENT
SUNDAY FORECAST ACTUALLY HAS SUSTAINED SOUTHERLY SPEEDS UP AROUND
15 MPH/GUSTS AROUND 20 MPH.
SUNDAY NIGHT THROUGH TUESDAY MARKS THE RETURN OF VARIOUS...LOW-
CONFIDENCE THUNDERSTORM CHANCES OF THE 20-30 PERCENT
VARIETY...THAT WILL UNDOUBTEDLY BE REFINED SEVERAL TIMES DURING
THE NEXT SEVERAL DAYS. FROM A GENERAL...SYNOPTIC SCALE
STANDPOINT...BOTH THE ECWMF/GFS BREAK DOWN THE RIDGE-DOMINATED
PATTERN FROM THE WEEKEND AND GRADUALLY BRINGS A QUASI-ZONAL
PATTERN AS ONE OR TWO FAIRLY LOW-AMPLITUDE SHORTWAVE TROUGHS OF
NOTE WORK INTO THE CENTRAL PLAINS FROM THE WEST. THIS SHOULD
SUPPORT A CONTINUED SURFACE PATTERN OF LIGHT BUT NOTICEABLY
SOUTHERLY BREEZES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1235 AM CDT WED AUG 14 2013
REST OF TNGT: VFR MAY EVENTUALLY DECAY TO MVFR VSBYS IN LGT FOG.
DWPT DEPRESSIONS ARE SMALL AND VSBYS TO THE E ARE NOW 7-9SM. THERE
DOES NOT APPEAR TO BE MUCH MSTR ALOFT...SO DO NOT EXPECT IFR FOG
ATTM. WINDS WILL BE LGT FROM THE E.
WED: WE ARE MONITORING THE MCS OVER THE SANDHILLS N OF LBF. IF
THIS CLUSTER OF TSTMS HOLDS TOGETHER...CURRENT TIMING WOULD BRING
IT INTO GRI 12-13Z. CIG/VSBYS WILL DECAY IN +TSRA WITH LLWS AND
VARIABLE/GUSTY WINDS. THEN VFR THEREAFTER. SCT TSTMS SHOULD
REDEVELOP LATE THIS AFTN OR THIS EVNG. WINDS WILL BECOME SE BUT
REMAIN BELOW 10 KTS.
CIG CONFIDENCE: MEDIUM
VSBY CONFIDENCE: LOW
WIND CONFIDENCE: HIGH EXCEPT NEAR ANY TSTMS
WX CONFIDENCE: MEDIUM
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HALBLAUB
SHORT TERM...WESELY
LONG TERM...PFANNKUCH
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
957 PM EDT THU AUG 15 2013
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH THE WEEKEND.
DRY WEATHER AND SLOWLY MODERATING TEMPERATURES CAN BE EXPECTED
THE NEXT FEW DAYS WITH WEEKEND HIGHS NEAR 80 AND OVERNIGHT LOWS
IN THE 50S.
&&
.NEAR TERM /THROUGH FRIDAY/...
10PM UPDATE...
QUICK UPDATE TO BUMP CLDS UP A BIT ACRS SRN TIER INTO THE
SUSQUEHANNA REGION, COURTESY OF S/WV MVG THRU. EXPECT MOCLDY CONDS
THRU MIDNIGHT BFR WV EXITS TO THE EAST THEN EXPECT FOG TO DVLP. NO
OTHER CHGS NEEDED TO GRIDS.
715 PM UPDATE...
ONLY MINIMAL CHGS NEEDED TO GRIDS AT THIS TIME. MAIN CHG WAS TO
SHOW MORE OF A RIDGE/VLY SPLIT FOR MIN TEMPS. DIURNAL CU IS
DISSIPATING ON TIME TONIGHT AND WITH HIPRES BUILDING INTO REGION,
SETUP LOOKS GOOD FOR RADNL VLY FOG AFT 06Z. TEMPS BY MRNG WL DIP
INTO THE M40S IN DEEPER VLY LOCALES WITH HIGHER TERRAIN RMNG
CLOSE TO 50.
2 PM UPDATE...
DEEP COOL NORTHWEST FLOW OVER CENTRAL NY AND NE PA. COLD ENOUGH
FOR LAKE ENHANCED DIURNAL CUMULUS THIS AFTN. THESE CLOUDS WILL
DIMINISH TO MAINLY CLEAR LATE TONIGHT. WITH SURFACE HIGH PRESSURE
MOVING IN FROM OHIO TO PA SFC WINDS WILL BE LIGHT TO CALM AGAIN.
VALLEY FOG WILL BE COMMON ACROSS THE SRN TIER AND CATSKILLS OF NY
AND NE PA. LOW TEMPS SIMILAR TO THIS MORNING. MOS WAS CLOSE THIS
MORNING AND WENT CLOSE TO PREVIOUS FORECAST AND MOS TONIGHT.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
2 PM UPDATE...
A QUIET DRY PERIOD WITH MODERATING TEMPERATURES. THE SURFACE HIGH
CONTINUES TO SLOWLY MOVE EAST TO BE CENTERED OVER NEW ENGLAND THIS
WEEKEND. UPPER LEVEL HEIGHTS GRADUALLY RISE DESPITE A WEAK TROF
FORMING OVER THE MIDWEST AND WRN GREAT LAKES. LITTLE DEEP MOISTURE
OVER THE AREA AND UPSTREAM FOR FRIDAY THEN MOISTURE WILL SLOWLY
MOVE NE MAKING IT INTO SRN PA SUNDAY. STILL FAR ENOUGH SOUTH TO
KEEP POPS OUT. FOR TEMPERATURES WENT CLOSE TO MOS WHICH SLOWLY
WARM TO NEAR NORMAL.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
145 PM THU UPDATE...
SLOWLY INCREASING 500MB HEIGHTS...AND PERSISTENCE OF SURFACE HIGH
PRESSURE /OR AT LEAST RIDGE/ FOR MOST OF THE PERIOD...LEADS TO
FAIRLY QUIET LONG TERM FORECAST WITH SLIGHTLY ABOVE CLIMATOLOGY
TEMPERATURES. WEAK REMAINS OF AN UPPER WAVE MAY SKIM NEAR NEPA
MONDAY...WITH CORRESPONDING SLIGHT CHANCE OF SHOWER OR
THUNDERSTORM...AND THEN SOMETIME TOWARDS NEXT THURSDAY A WEAK
FRONT MAY TRY TO DROP THROUGH. OTHERWISE LACK OF FORCING AND
FAIRLY DRY COLUMN WILL KEEP THINGS DRY WITH GRADUAL DAY-BY-DAY WARMING.
&&
.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
DIURNAL CU IS QUICKLY DISSIPATING, GIVING WAY TO CLEAR SKIES AND
LIGHT WINDS FOR THE OVERNIGHT. LATEST RAP SOUNDING PROFILES ARE
SUGGESTIVE OF VALLEY FOG AT ELM, AND THE POSSIBILITY OF BRIEF LIGHT FOG
AT ITH WHERE CAYUGA LAKE MAY ADD SOME LOW LEVEL MOISTURE. A BETTER
SHOT FOR LIGHT FOG APPEARS TO BE AT RME, WHERE FLOW OFF LAKE
ONTARIO WILL KEEP BL DEW POINTS JUST HIGH ENOUGH TO CAUSE SOME
VIS RESTRICTIONS.
RME AND ITH WILL FLIRT WITH MVFR VISIBILITIES BETWEEN 3SM AND 5SM.
ELM IS EXPECTED TO FALL INTO IFR TERRITORY AFTER 8Z, WITH
VISIBILITIES AROUND 1/2SM AND CEILINGS OF 200 FEET.
MOSTLY CLEAR SKIES AND VFR CONDITIONS ARE FORECAST FOR FRIDAY.
OUTLOOK...
FRI NIGHT THRU TUE...MAINLY VFR EXCEPT VALLEY FOG EARLY EACH
MORNING...PRIMARILY AT KELM.
&&
.CLIMATE...
220 PM UPDATE...
LOW TEMPERATURES TONIGHT WILL BE CLOSE TO THE RECORD AT AVOCA BUT
TOO WARM AT SYRACUSE AND BINGHAMTON. RECORD LOWS AVP 49 IN 1979
1945 1927... BGM 46 IN 1972... SYR 47 IN 1972 AND 1968...
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...TAC
NEAR TERM...PVN/TAC
SHORT TERM...TAC
LONG TERM...MDP
AVIATION...DJP
CLIMATE...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
719 PM EDT THU AUG 15 2013
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH THE WEEKEND.
DRY WEATHER AND SLOWLY MODERATING TEMPERATURES CAN BE EXPECTED
THE NEXT FEW DAYS WITH WEEKEND HIGHS NEAR 80 AND OVERNIGHT LOWS
IN THE 50S.
&&
.NEAR TERM /THROUGH FRIDAY/...
715 PM UPDATE...
ONLY MINIMAL CHGS NEEDED TO GRIDS AT THIS TIME. MAIN CHG WAS TO
SHOW MORE OF A RIDGE/VLY SPLIT FOR MIN TEMPS. DIURNAL CU IS
DISSIPATING ON TIME TONIGHT AND WITH HIPRES BUILDING INTO REGION,
SETUP LOOKS GOOD FOR RADNL VLY FOG AFT 06Z. TEMPS BY MRNG WL DIP
INTO THE M40S IN DEEPER VLY LOCALES WITH HIGHER TERRAIN RMNG
CLOSE TO 50.
2 PM UPDATE...
DEEP COOL NORTHWEST FLOW OVER CENTRAL NY AND NE PA. COLD ENOUGH
FOR LAKE ENHANCED DIURNAL CUMULUS THIS AFTN. THESE CLOUDS WILL
DIMINISH TO MAINLY CLEAR LATE TONIGHT. WITH SURFACE HIGH PRESSURE
MOVING IN FROM OHIO TO PA SFC WINDS WILL BE LIGHT TO CALM AGAIN.
VALLEY FOG WILL BE COMMON ACROSS THE SRN TIER AND CATSKILLS OF NY
AND NE PA. LOW TEMPS SIMILAR TO THIS MORNING. MOS WAS CLOSE THIS
MORNING AND WENT CLOSE TO PREVIOUS FORECAST AND MOS TONIGHT.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
2 PM UPDATE...
A QUIET DRY PERIOD WITH MODERATING TEMPERATURES. THE SURFACE HIGH
CONTINUES TO SLOWLY MOVE EAST TO BE CENTERED OVER NEW ENGLAND THIS
WEEKEND. UPPER LEVEL HEIGHTS GRADUALLY RISE DESPITE A WEAK TROF
FORMING OVER THE MIDWEST AND WRN GREAT LAKES. LITTLE DEEP MOISTURE
OVER THE AREA AND UPSTREAM FOR FRIDAY THEN MOISTURE WILL SLOWLY
MOVE NE MAKING IT INTO SRN PA SUNDAY. STILL FAR ENOUGH SOUTH TO
KEEP POPS OUT. FOR TEMPERATURES WENT CLOSE TO MOS WHICH SLOWLY
WARM TO NEAR NORMAL.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
145 PM THU UPDATE...
SLOWLY INCREASING 500MB HEIGHTS...AND PERSISTENCE OF SURFACE HIGH
PRESSURE /OR AT LEAST RIDGE/ FOR MOST OF THE PERIOD...LEADS TO
FAIRLY QUIET LONG TERM FORECAST WITH SLIGHTLY ABOVE CLIMATOLOGY
TEMPERATURES. WEAK REMAINS OF AN UPPER WAVE MAY SKIM NEAR NEPA
MONDAY...WITH CORRESPONDING SLIGHT CHANCE OF SHOWER OR
THUNDERSTORM...AND THEN SOMETIME TOWARDS NEXT THURSDAY A WEAK
FRONT MAY TRY TO DROP THROUGH. OTHERWISE LACK OF FORCING AND
FAIRLY DRY COLUMN WILL KEEP THINGS DRY WITH GRADUAL DAY-BY-DAY WARMING.
&&
.AVIATION /23Z THURSDAY THROUGH TUESDAY/...
DIURNAL CU IS QUICKLY DISSIPATING, GIVING WAY TO CLEAR SKIES AND
LIGHT WINDS FOR THE OVERNIGHT. LATEST RAP SOUNDING PROFILES ARE
SUGGESTIVE OF VALLEY FOG AT ELM, AND THE POSSIBILITY OF BRIEF LIGHT FOG
AT ITH WHERE CAYUGA LAKE MAY ADD SOME LOW LEVEL MOISTURE. A BETTER
SHOT FOR LIGHT FOG APPEARS TO BE AT RME, WHERE FLOW OFF LAKE
ONTARIO WILL KEEP BL DEW POINTS JUST HIGH ENOUGH TO CAUSE SOME
VIS RESTRICTIONS.
RME AND ITH WILL FLIRT WITH MVFR VISIBILITIES BETWEEN 3SM AND 5SM.
ELM IS EXPECTED TO FALL INTO IFR TERRITORY AFTER 8Z, WITH
VISIBILITIES AROUND 1/2SM AND CEILINGS OF 200 FEET.
MOSTLY CLEAR SKIES AND VFR CONDITIONS ARE FORECAST FOR FRIDAY.
OUTLOOK...
FRI NIGHT THRU TUE...MAINLY VFR EXCEPT VALLEY FOG EARLY EACH
MORNING...PRIMARILY AT KELM.
&&
.CLIMATE...
220 PM UPDATE...
LOW TEMPERATURES TONIGHT WILL BE CLOSE TO THE RECORD AT AVOCA BUT
TOO WARM AT SYRACUSE AND BINGHAMTON. RECORD LOWS AVP 49 IN 1979
1945 1927... BGM 46 IN 1972... SYR 47 IN 1972 AND 1968...
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...TAC
NEAR TERM...PVN/TAC
SHORT TERM...TAC
LONG TERM...MDP
AVIATION...DJP
CLIMATE...TAC
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
718 PM EDT THU AUG 15 2013
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH THE WEEKEND.
DRY WEATHER AND SLOWLY MODERATING TEMPERATURES CAN BE EXPECTED
THE NEXT FEW DAYS WITH WEEKEND HIGHS NEAR 80 AND OVERNIGHT LOWS
IN THE 50S.
&&
.NEAR TERM /THROUGH FRIDAY/...
2 PM UPDATE...
DEEP COOL NORTHWEST FLOW OVER CENTRAL NY AND NE PA. COLD ENOUGH
FOR LAKE ENHANCED DIURNAL CUMULUS THIS AFTN. THESE CLOUDS WILL
DIMINISH TO MAINLY CLEAR LATE TONIGHT. WITH SURFACE HIGH PRESSURE
MOVING IN FROM OHIO TO PA SFC WINDS WILL BE LIGHT TO CALM AGAIN.
VALLEY FOG WILL BE COMMON ACROSS THE SRN TIER AND CATSKILLS OF NY
AND NE PA. LOW TEMPS SIMILAR TO THIS MORNING. MOS WAS CLOSE THIS
MORNING AND WENT CLOSE TO PREVIOUS FORECAST AND MOS TONIGHT.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
2 PM UPDATE...
A QUIET DRY PERIOD WITH MODERATING TEMPERATURES. THE SURFACE HIGH
CONTINUES TO SLOWLY MOVE EAST TO BE CENTERED OVER NEW ENGLAND THIS
WEEKEND. UPPER LEVEL HEIGHTS GRADUALLY RISE DESPITE A WEAK TROF
FORMING OVER THE MIDWEST AND WRN GREAT LAKES. LITTLE DEEP MOISTURE
OVER THE AREA AND UPSTREAM FOR FRIDAY THEN MOISTURE WILL SLOWLY
MOVE NE MAKING IT INTO SRN PA SUNDAY. STILL FAR ENOUGH SOUTH TO
KEEP POPS OUT. FOR TEMPERATURES WENT CLOSE TO MOS WHICH SLOWLY
WARM TO NEAR NORMAL.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
145 PM THU UPDATE...
SLOWLY INCREASING 500MB HEIGHTS...AND PERSISTENCE OF SURFACE HIGH
PRESSURE /OR AT LEAST RIDGE/ FOR MOST OF THE PERIOD...LEADS TO
FAIRLY QUIET LONG TERM FORECAST WITH SLIGHTLY ABOVE CLIMATOLOGY
TEMPERATURES. WEAK REMAINS OF AN UPPER WAVE MAY SKIM NEAR NEPA
MONDAY...WITH CORRESPONDING SLIGHT CHANCE OF SHOWER OR
THUNDERSTORM...AND THEN SOMETIME TOWARDS NEXT THURSDAY A WEAK
FRONT MAY TRY TO DROP THROUGH. OTHERWISE LACK OF FORCING AND
FAIRLY DRY COLUMN WILL KEEP THINGS DRY WITH GRADUAL DAY-BY-DAY WARMING.
&&
.AVIATION /23Z THURSDAY THROUGH TUESDAY/...
DIURNAL CU IS QUICKLY DISSIPATING, GIVING WAY TO CLEAR SKIES AND
LIGHT WINDS FOR THE OVERNIGHT. LATEST RAP SOUNDING PROFILES ARE
SUGGESTIVE OF VALLEY FOG AT ELM, AND THE POSSIBILITY OF BRIEF LIGHT FOG
AT ITH WHERE CAYUGA LAKE MAY ADD SOME LOW LEVEL MOISTURE. A BETTER
SHOT FOR LIGHT FOG APPEARS TO BE AT RME, WHERE FLOW OFF LAKE
ONTARIO WILL KEEP BL DEW POINTS JUST HIGH ENOUGH TO CAUSE SOME
VIS RESTRICTIONS.
RME AND ITH WILL FLIRT WITH MVFR VISIBILITIES BETWEEN 3SM AND 5SM.
ELM IS EXPECTED TO FALL INTO IFR TERRITORY AFTER 8Z, WITH
VISIBILITIES AROUND 1/2SM AND CEILINGS OF 200 FEET.
MOSTLY CLEAR SKIES AND VFR CONDITIONS ARE FORECAST FOR FRIDAY.
OUTLOOK...
FRI NIGHT THRU TUE...MAINLY VFR EXCEPT VALLEY FOG EARLY EACH
MORNING...PRIMARILY AT KELM.
&&
.CLIMATE...
220 PM UPDATE...
LOW TEMPERATURES TONIGHT WILL BE CLOSE TO THE RECORD AT AVOCA BUT
TOO WARM AT SYRACUSE AND BINGHAMTON. RECORD LOWS AVP 49 IN 1979
1945 1927... BGM 46 IN 1972... SYR 47 IN 1972 AND 1968...
145 PM UPDATE...
RECORD DAILY LOW TEMPERATURE AT AVOCA PA TIED THIS MORNING. 632 AM
EDT TEMPERATURE OF 46 WHICH TIES THE RECORD FROM 1907. ALSO A FEW
UNOFFICIAL LOW TEMPERATURES IN THE U30S. BINGHAMTON RECORD REMAINS
47 DEGREES SET IN 1963 AND 1964 /IT HIT 48 THIS MORNING/.
MEANWHILE THE SYRACUSE DAILY RECORD LOW OF 46 DEGREES FROM 1972
WAS NEVER THREATENED...WITH THE TEMPERATURE HAVING DROPPED ONLY TO
54 EARLIER THIS MORNING.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...TAC
NEAR TERM...PVN/TAC
SHORT TERM...TAC
LONG TERM...MDP
AVIATION...DJP
CLIMATE...
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
800 PM EDT THU AUG 15 2013
.SYNOPSIS...
A WARM FRONT ACROSS NORTHERN FLORIDA WILL LIFT NORTH TO THE NORTH
AND SOUTH CAROLINA COAST LATE SATURDAY NIGHT. TROPICAL MOISTURE
RIDING OVER THIS FRONT WILL PRODUCE PERIODS OF SHOWERS AND
THUNDERSTORMS THROUGH THE WEEKEND. BERMUDA HIGH PRESSURE OFFSHORE
WILL BRING SOUTH WINDS WITH WARMER TEMPERATURES EXPECTED.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 730 PM THURSDAY...BASED ON RADAR TRENDS AND REVIEW OF 12Z
ECMWF...THE 18Z GFS...AND THE LATEST FEW HRRR RUNS...I HAVE
INCREASED POPS FOR THE OVERNIGHT HOURS TO 70-100 PERCENT. AN AREA OF
MAINLY LIGHT RAIN IS PUSHING ACROSS THE THE REGION ALONG AND SOUTH
OF A LINE FROM FLORENCE TO MARION TO WHITEVILLE. THIS IS JUST
SETTING THE STAGE FOR WHAT SHOULD BE MORE SUBSTANTIAL RAINFALL
OVERNIGHT AS ISENTROPIC LIFT INCREASES ALONG THE 305-310K THETA
SURFACES. THE BULK OF THE RAINFALL LATER THIS EVENING SHOULD DEVELOP
ACROSS EASTERN SOUTH CAROLINA...BUT AFTER MIDNIGHT RAIN SHOULD
FOLLOW THE BETTER ISENTROPIC LIFT NORTHWARD INTO SE AND S-CENTRAL
NORTH CAROLINA.
IT IS WORTH NOTING TODAY`S TEMPERATURES SHOULD SET A RECORD IN
WILMINGTON FOR THE COLDEST HIGH TEMPERATURES EVER RECORDED ON THIS
DATE. AS LONG AS NORTHEAST WINDS CONTINUE THROUGH THE EVENING WE
SHOULD ESTABLISH THIS NEW RECORD.
OLD RECORD COLD HIGH TODAY`S HIGH NORMAL HIGH
WILMINGTON 76 IN 2004 71 88
FLORENCE 72 IN 2004 76 90
N. MYRTLE BEACH 78 IN 2004* 71 86
LUMBERTON 70 IN 2004* 77 88
* N. MYRTLE BEACH AND LUMBERTON RECORDS ONLY GO BACK TO 2000 WHICH
IS NOT A LONG ENOUGH PERIOD OF RECORD TO BE STATISTICALLY
SIGNIFICANT.
ADDITIONALLY...TODAY`S WILMINGTON HIGH TEMPERATURE SHOULD BE THE 7TH
COLDEST HIGH IN HISTORY FOR ANY DATE IN AUGUST. THE ALL-TIME COLDEST
AUGUST DAILY HIGH TEMPERATURE IN WILMINGTON WAS 67 DEGREES SET ON
8/27/1927. RECORDS BEGAN IN WILMINGTON IN 1874.
PREVIOUS DISCUSSION FROM 300 PM FOLLOWS...
HAVE INCREASED POPS SLIGHTLY ACROSS THE SOUTHWEST ZONES AS THE
PRECIPITATION WITH THE NEXT SHORTWAVE IS EXPANDING MORE THAN
EXPECTED. THE 1200 UTC GFS SHOWS THIS FAIRLY WELL AND THE OFFICIAL
FORECAST WILL FEATURED REMAINDER WILL FEATURE RAPIDLY DIMINISHING
POPS AND AREAS OF DRIZZLE. FOR TONIGHT...TWO AREAS OF LIFT...ANOTHER
SHORTWAVE TRAVERSING FURTHER INLAND AS THE MAIN TROUGH DEEPENS OUT
ACROSS THE MISSISSIPPI VALLEY AND THE SECOND...THE FRONT BOWING AND
APPROACHING THE COAST. THESE BOTH OCCUR LATER. I HAVE CONTINUED THE
LOWER POPS UNTIL ABOUT 0600 UTC THEN RAMP UP QUICKLY TO LIKELY WHEN
BOTH FEATURES BEGIN TO SIGNIFICANTLY IMPACT THE FORECAST AREA.
TEMPERATURES ARE CHARACTERISTIC OF A COLD AIR WEDGE...ALL OVER THE
PLACE AND SHOWING NON TRADITIONAL TRENDS. TEMPERATURES ARE
INCREASING OVER INLAND AREAS WHERE THE RAIN HAS ENDED AND
EVAPORATIVE COOLING HAS CEASED. WE COULD RISE ENOUGH THE NEXT FEW
HOURS TO SHOW A DECREASE OVERNIGHT BUT RANGES WILL BE CLOSE. THE
FRONT APPROACHING THE COAST LATE WILL BE PROBLEMATIC AS WELL.
OVERALL I HAVE UNDERCUT GUIDANCE WHICH HAS BEEN MORE REPRESENTATIVE
OF THE AIRMASS BUT CONFIDENCE IS NOT HIGH.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/...
AS OF 325 PM THURSDAY...THE COOLER AND WETTER TREND WILL CONTINUE
FOR THE ENTIRE PERIOD. SEVERAL WAVES OF ENERGY WILL MOVE ALONG THE
FRONT BRING A CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY. THE
STATIONARY FRONT WILL MEANDERS IN AND NEAR THE FORECAST AREA AND THE
925 TO 800 MB MOISTURE TRANSPORT AND BEST LIFT IS SEEN ON FRIDAY AND
AGAIN ON SATURDAY. THE STRONGEST FORCING APPEARS TO BE ON SATURDAY
AFTERNOON. QPF VALUES OF 2 TO 3 INCHES ARE EXPECTED OVER THE
FORECAST. TEMPERATURES ARE EXPECTED TO REACH THE UPPER 70S AND LOWS
IN THE MID TO UPPER 60S FRIDAY NIGHT AND NEAR 70 ON SATURDAY NIGHT.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 325 PM THURSDAY...MODELS SEEM TO KEEP WANTING TO SLOW THE
NORTHWARD ADVANCE OF THE FRONTAL BOUNDARY...WHICH GIVEN AMPLE RAIN
OCCURRING WITHIN THE WEDGE SEEMS PLAUSIBLE. THAT SAID RAISED POPS
AND LOWERED TEMPS JUST A LITTLE ON SUNDAY...WHICH MAY STILL BE
RATHER UNSETTLED ALBEIT NOT SO MUCH AS THE FEW DAYS PRIOR. MONDAY
MAY BRING A QUIETER AFTERNOON AS THE UPPER RIDGE TRIES TO BUILD
WESTWARD...BUT COMPARED TO PREV GUIDANCE RUNS NOW APPEARS TO NOT
MAKE MUCH PROGRESS AT ALL. MONDAY WILL BRING A LITTLE WARMER
AFTERNOON BUT NOT SURE IT MAKES IT BACK TO CLIMO AS THERE MAY
STILL BE QUITE A BIT OF LINGERING CLOUD COVER TO INHIBIT
INSOLATION. ON TUESDAY THE UPPER RIDGE OVER THE WEST-CENTRAL U.S.
BUILDS BUT THE ONE OVER THE WEST ATLANTIC FLATTENS SOMEWHAT AS AN
ODD NE TO SW TROUGH AXIS IMPINGES UPON IT FROM THE N. THIS MAY
ALLOW SOME CHANNELED VORT MAXES TO CROSS THE CAROLINAS. SURFACE
AND LOW LEVEL FLOW ARE QUITE WEAK...EVEN FOR AUGUST. THIS COULD
POTENTIALLY LEAD TO AN INITIAL SCATTERING OF THUNDERSTORMS WITH
SLOW AND ERRATIC MOTION THAT GENERATE ADDITIONAL STORM DEVELOPMENT
WITH VERY RANDOM PLACEMENT. RAISED POPS TO A LITTLE ABOVE CLIMO
ALTHOUGH TEMPS LOOK CLOSE TO NORMAL. WEDNESDAY LOOKS VERY SIMILAR
TO TUESDAY. PIEDMONT TROUGH MAY SHARPEN ON THURSDAY AS THE WESTERN
RIDGE CONTINUES TO BUILD.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
AS OF 00Z...CIGS ARE HOLDING FAIRLY STEADY IN THE MVFR RANGE AT THE
COASTAL TERMINALS KILM/KCRE/KMYR...WHILE THE INLAND TERMINALS
KFLO/KLBT HAVE VFR CIGS. CIGS HAVE NOT SHOWN A DECREASE YET DESPITE
LIGHT RAIN FALLING INTO A COOL DOME OF AIR AT THE SURFACE. RADAR
INDICATES RAIN IS CURRENTLY DECREASING AND HEAVIEST SW OF KMYR.
MVFR CIGS SHOULD CONTINUE AT THE COASTAL TERMINALS THIS EVENING...AND
WILL DEVELOP INTO KFLO LATER THIS EVENING AND OVERNIGHT INTO KLBT. CIGS
AT THE COASTAL TERMINALS WILL BECOME IFR BY OR JUST AFTER MIDNIGHT
AS RAIN RE-DEVELOPS. IFR CIGS WILL THEN DEVELOP AT THE INLAND
TERMINALS OVERNIGHT AS THE HEAVIEST OF THE RAIN SPREADS INLAND.
VSBYS SHOULD REMAIN VFR THIS EVENING THEN DROP TO MVFR IN RAIN
OVERNIGHT. IFR VSBYS ARE POSSIBLE IN HEAVIER AREAS OF RAIN. THE
CHANCE OF THUNDERSTORMS SHOULD REMAIN REMOTE.
EXPECT IFR TO LIFT TO MVFR BY MID-MORNING. MVFR CIGS SHOULD LIFT TO
VFR IN THE AFTERNOON AT THE COASTAL TERMINALS BUT MAY PERSIST INLAND
INTO THE AFTERNOON. TEMPO MVFR VSBYS IN RAIN APPEAR LIKELY AT THE
COASTAL TERMINALS IN THE AFTERNOON.
EXTENDED OUTLOOK...SHOWERS AND ISOLATED THUNDERSTORMS EXPECTED
THROUGH SUNDAY WITH TEMPO MVFR CIGS AND MVFR/IFR VSBYS. CONTINUED
CHANCE OF SHOWERS MONDAY AND TUESDAY BUT WITH LESS COVERAGE.
&&
.MARINE...
NEAR TERM/THROUGH TONIGHT/...
AS OF 730 PM THURSDAY...WINDS NEAR AND NORTH OF CAPE FEAR REMAIN
NEAR 20 KNOTS...WHILE SOUTH OF CAPE FEAR WINDS ARE CLOSER TO 15
KNOTS WITH 10 KNOTS AT THE BEACHES. THE PRESSURE GRADIENT IS
INDICATED BY ALMOST ALL THE MODELS TO WEAKEN OVERNIGHT WITH
DIMINISHING WIND SPEEDS EXPECTED. MAINLY MINOR CHANGES HAVE BEEN
MADE TO WINDS/SEAS TO REFLECT CURRENTLY OBSERVED CONDITIONS.
PREVIOUS DISCUSSION FROM 300 PM FOLLOWS...
WINDS AND SEAS CONTINUE TO HOVER NEAR 20 KNOTS AND 4-6 FEET ACROSS
THE COASTAL WATERS THIS AFTERNOON. MODEL GUIDANCE SHOWS THE COLD AIR
WEDGE WEAKENING THROUGH THE OVERNIGHT HOURS HENCE THE WINDS SHOULD
DECREASE IN INTENSITY DRAMATICALLY. WE SHOULD EVENTUALLY SEE AROUND
TEN KNOTS FROM THE NORTHEAST WITH A TURN TO THE EAST VERY LATE AS
THE ASSOCIATED FRONT MAKES A RUN TOWARD THE COAST. SEAS FOLLOW THE
SAME TREND WITH 4-6 FEET SCALING BACK TO 2-4 FEET.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 325 PM THURSDAY...THE STATIONARY FRONTAL BOUNDARY WILL BE
WAVERING ACROSS THE WATERS AND JUST INLAND THROUGH THE PERIOD.
WINDS WILL BE RELATIVELY LIGHT FROM THE NORTHEAST ON SATURDAY AND
VARIABLE IN DIRECTION ON SUNDAY. SEAS ARE EXPECTED TO BE MAINLY
BETWEEN 2 AND 3 FEET.
LONG TERM /SUNDAY THROUGH TUESDAY/...
AS OF 325 PM THURSDAY...STALLED OR NEARLY STALLED OUT FRONTAL
BOUNDARIES ALWAYS MAKE FOR A PROBLEMATIC WIND FORECAST AND SUNDAY
APPEARS TO BE NO DIFFERENT. THERE IS LOW CONFIDENCE AT WHICH THE
SPEED THE BOUNDARY LIFTS TO THE NORTH AND MODEL GUIDANCE KEEPS
WANTING TO SLOW ITS PROGRESS. IT DOES APPEAR THAT A SOUTHERLY
COMPONENT WILL BECOME ESTABLISHED HOWEVER EVEN IF ONLY LATER IN
THE DAY. SPEEDS WILL BE LIGHT HOWEVER KEEPING SEAS NO HIGHER THAN
TH 2 TO 3 FT RANGE. S TO SW WINDS REMAIN LIGHT ON MONDAY AND SEAS
UNCHANGED. A SOUTHERLY COMPONENT REMAINS ON TUESDAY BUT SLIGHT
VARIATION FROM SE TO SW SEEMS POSSIBLE AS THE GRADIENT GETS QUITE
WEAK EVEN BY AUGUST STANDARDS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SHK
NEAR TERM...SHK
SHORT TERM...DRH
LONG TERM...MBB/SGL
AVIATION...MRR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
744 PM EDT THU AUG 15 2013
.SYNOPSIS...
A WARM FRONT ACROSS NORTHERN FLORIDA WILL LIFT NORTH TO THE NORTH
AND SOUTH CAROLINA COAST LATE SATURDAY NIGHT. TROPICAL MOISTURE
RIDING OVER THIS FRONT WILL PRODUCE PERIODS OF SHOWERS AND
THUNDERSTORMS THROUGH THE WEEKEND. BERMUDA HIGH PRESSURE OFFSHORE
WILL BRING SOUTH WINDS WITH WARMER TEMPERATURES EXPECTED.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 730 PM THURSDAY...BASED ON RADAR TRENDS AND REVIEW OF 12Z
ECMWF...THE 18Z GFS...AND THE LATEST FEW HRRR RUNS...I HAVE
INCREASED POPS FOR THE OVERNIGHT HOURS TO 70-100 PERCENT. AN AREA OF
MAINLY LIGHT RAIN IS PUSHING ACROSS THE THE REGION ALONG AND SOUTH
OF A LINE FROM FLORENCE TO MARION TO WHITEVILLE. THIS IS JUST
SETTING THE STAGE FOR WHAT SHOULD BE MORE SUBSTANTIAL RAINFALL
OVERNIGHT AS ISENTROPIC LIFT INCREASES ALONG THE 305-310K THETA
SURFACES. THE BULK OF THE RAINFALL LATER THIS EVENING SHOULD DEVELOP
ACROSS EASTERN SOUTH CAROLINA...BUT AFTER MIDNIGHT RAIN SHOULD
FOLLOW THE BETTER ISENTROPIC LIFT NORTHWARD INTO SE AND S-CENTRAL
NORTH CAROLINA.
IT IS WORTH NOTING TODAY`S TEMPERATURES SHOULD SET A RECORD IN
WILMINGTON FOR THE COLDEST HIGH TEMPERATURES EVER RECORDED ON THIS
DATE. AS LONG AS NORTHEAST WINDS CONTINUE THROUGH THE EVENING WE
SHOULD ESTABLISH THIS NEW RECORD.
OLD RECORD COLD HIGH TODAY`S HIGH NORMAL HIGH
WILMINGTON 76 IN 2004 71 88
FLORENCE 72 IN 2004 76 90
N. MYRTLE BEACH 78 IN 2004* 71 86
LUMBERTON 70 IN 2004* 77 88
* N. MYRTLE BEACH AND LUMBERTON RECORDS ONLY GO BACK TO 2000 WHICH
IS NOT A LONG ENOUGH PERIOD OF RECORD TO BE STATISTICALLY
SIGNIFICANT.
ADDITIONALLY...TODAY`S WILMINGTON HIGH TEMPERATURE SHOULD BE THE 7TH
COLDEST HIGH IN HISTORY FOR ANY DATE IN AUGUST. THE ALL-TIME COLDEST
AUGUST DAILY HIGH TEMPERATURE IN WILMINGTON WAS 67 DEGREES SET ON
8/27/1927. RECORDS BEGAN IN WILMINGTON IN 1874.
PREVIOUS DISCUSSION FROM 300 PM FOLLOWS...
HAVE INCREASED POPS SLIGHTLY ACROSS THE SOUTHWEST ZONES AS THE
PRECIPITATION WITH THE NEXT SHORTWAVE IS EXPANDING MORE THAN
EXPECTED. THE 1200 UTC GFS SHOWS THIS FAIRLY WELL AND THE OFFICIAL
FORECAST WILL FEATURED REMAINDER WILL FEATURE RAPIDLY DIMINISHING
POPS AND AREAS OF DRIZZLE. FOR TONIGHT...TWO AREAS OF LIFT...ANOTHER
SHORTWAVE TRAVERSING FURTHER INLAND AS THE MAIN TROUGH DEEPENS OUT
ACROSS THE MISSISSIPPI VALLEY AND THE SECOND...THE FRONT BOWING AND
APPROACHING THE COAST. THESE BOTH OCCUR LATER. I HAVE CONTINUED THE
LOWER POPS UNTIL ABOUT 0600 UTC THEN RAMP UP QUICKLY TO LIKELY WHEN
BOTH FEATURES BEGIN TO SIGNIFICANTLY IMPACT THE FORECAST AREA.
TEMPERATURES ARE CHARACTERISTIC OF A COLD AIR WEDGE...ALL OVER THE
PLACE AND SHOWING NON TRADITIONAL TRENDS. TEMPERATURES ARE
INCREASING OVER INLAND AREAS WHERE THE RAIN HAS ENDED AND
EVAPORATIVE COOLING HAS CEASED. WE COULD RISE ENOUGH THE NEXT FEW
HOURS TO SHOW A DECREASE OVERNIGHT BUT RANGES WILL BE CLOSE. THE
FRONT APPROACHING THE COAST LATE WILL BE PROBLEMATIC AS WELL.
OVERALL I HAVE UNDERCUT GUIDANCE WHICH HAS BEEN MORE REPRESENTATIVE
OF THE AIRMASS BUT CONFIDENCE IS NOT HIGH.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 325 PM THURSDAY...THE COOLER AND WETTER TREND WILL CONTINUE
FOR THE ENTIRE PERIOD. SEVERAL WAVES OF ENERGY WILL MOVE ALONG THE
FRONT BRING A CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY. THE
STATIONARY FRONT WILL MEANDERS IN AND NEAR THE FORECAST AREA AND THE
925 TO 800 MB MOISTURE TRANSPORT AND BEST LIFT IS SEEN ON FRIDAY AND
AGAIN ON SATURDAY. THE STRONGEST FORCING APPEARS TO BE ON SATURDAY
AFTERNOON. QPF VALUES OF 2 TO 3 INCHES ARE EXPECTED OVER THE
FORECAST. TEMPERATURES ARE EXPECTED TO REACH THE UPPER 70S AND LOWS
IN THE MID TO UPPER 60S FRIDAY NIGHT AND NEAR 70 ON SATURDAY NIGHT.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 325 PM THURSDAY...MODELS SEEM TO KEEP WANTING TO SLOW THE
NORTHWARD ADVANCE OF THE FRONTAL BOUNDARY...WHICH GIVEN AMPLE RAIN
OCCURRING WITHIN THE WEDGE SEEMS PLAUSIBLE. THAT SAID RAISED POPS
AND LOWERED TEMPS JUST A LITTLE ON SUNDAY...WHICH MAY STILL BE
RATHER UNSETTLED ALBEIT NOT SO MUCH AS THE FEW DAYS PRIOR. MONDAY
MAY BRING A QUIETER AFTERNOON AS THE UPPER RIDGE TRIES TO BUILD
WESTWARD...BUT COMPARED TO PREV GUIDANCE RUNS NOW APPEARS TO NOT
MAKE MUCH PROGRESS AT ALL. MONDAY WILL BRING A LITTLE WARMER
AFTERNOON BUT NOT SURE IT MAKES IT BACK TO CLIMO AS THERE MAY
STILL BE QUITE A BIT OF LINGERING CLOUD COVER TO INHIBIT
INSOLATION. ON TUESDAY THE UPPER RIDGE OVER THE WEST-CENTRAL U.S.
BUILDS BUT THE ONE OVER THE WEST ATLANTIC FLATTENS SOMEWHAT AS AN
ODD NE TO SW TROUGH AXIS IMPINGES UPON IT FROM THE N. THIS MAY
ALLOW SOME CHANNELED VORT MAXES TO CROSS THE CAROLINAS. SURFACE
AND LOW LEVEL FLOW ARE QUITE WEAK...EVEN FOR AUGUST. THIS COULD
POTENTIALLY LEAD TO AN INITIAL SCATTERING OF THUNDERSTORMS WITH
SLOW AND ERRATIC MOTION THAT GENERATE ADDITIONAL STORM DEVELOPMENT
WITH VERY RANDOM PLACEMENT. RAISED POPS TO A LITTLE ABOVE CLIMO
ALTHOUGH TEMPS LOOK CLOSE TO NORMAL. WEDNESDAY LOOKS VERY SIMILAR
TO TUESDAY. PIEDMONT TROUGH MAY SHARPEN ON THURSDAY AS THE WESTERN
RIDGE CONTINUES TO BUILD.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
AS OF 00Z...CIGS ARE HOLDING FAIRLY STEADY IN THE MVFR RANGE AT THE
COASTAL TERMINALS KILM/KCRE/KMYR...WHILE THE INLAND TERMINALS
KFLO/KLBT HAVE VFR CIGS. CIGS HAVE NOT SHOWN A DECREASE YET DESPITE
LIGHT RAIN FALLING INTO A COOL DOME OF AIR AT THE SURFACE. RADAR
INDICATES RAIN IS DECREASING AND HEAVIEST SW OF KMYR.
MVFR CIGS SHOULD CONTINUE AT THE COASTAL TERMINALS THIS EVENING AND
GRADUALLY DEVELOP INTO KFLO LATER THIS EVENING AND OVERNIGHT INTO
KLBT. CIGS AT THE TERMINALS WILL BECOME IFR OVERNIGHT AS RAIN
RE-DEVELOPS AND WIND SPEEDS DECREASE. VSBYS SHOULD REMAIN VFR THIS
EVENING THEN DROP TO MVFR AS THE RAIN DEVELOPS OVERNIGHT.
EXPECT IFR TO LIFT TO MVFR BY MID-MORNING. MVFR CIGS SHOULD LIFT TO
VFR IN THE AFTERNOON AT THE COASTAL TERMINALS BUT MAY PERSIST INLAND
INTO THE AFTERNOON. TEMPO MVFR VSBYS IN RAIN APPEAR LIKELY AT THE
COASTAL TERMINALS IN THE AFTERNOON.
EXTENDED OUTLOOK...SHOWERS AND ISOLATED THUNDERSTORMS EXPECTED
THROUGH SUNDAY WITH TEMPO MVFR CIGS AND MVFR/IFR VSBYS. CONTINUED
CHANCE OF SHOWERS MONDAY AND TUESDAY BUT WITH LESS COVERAGE.
&&
.MARINE...
NEAR TERM/THROUGH TONIGHT/...
AS OF 730 PM THURSDAY...WINDS NEAR AND NORTH OF CAPE FEAR REMAIN
NEAR 20 KNOTS...WHILE SOUTH OF CAPE FEAR WINDS ARE CLOSER TO 15
KNOTS WITH 10 KNOTS AT THE BEACHES. THE PRESSURE GRADIENT IS
INDICATED BY ALMOST ALL THE MODELS TO WEAKEN OVERNIGHT WITH
DIMINISHING WIND SPEEDS EXPECTED. MAINLY MINOR CHANGES HAVE BEEN
MADE TO WINDS/SEAS TO REFLECT CURRENTLY OBSERVED CONDITIONS.
PREVIOUS DISCUSSION FROM 300 PM FOLLOWS...
WINDS AND SEAS CONTINUE TO HOVER NEAR 20 KNOTS AND 4-6 FEET ACROSS
THE COASTAL WATERS THIS AFTERNOON. MODEL GUIDANCE SHOWS THE COLD AIR
WEDGE WEAKENING THROUGH THE OVERNIGHT HOURS HENCE THE WINDS SHOULD
DECREASE IN INTENSITY DRAMATICALLY. WE SHOULD EVENTUALLY SEE AROUND
TEN KNOTS FROM THE NORTHEAST WITH A TURN TO THE EAST VERY LATE AS
THE ASSOCIATED FRONT MAKES A RUN TOWARD THE COAST. SEAS FOLLOW THE
SAME TREND WITH 4-6 FEET SCALING BACK TO 2-4 FEET.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 325 PM THURSDAY...THE STATIONARY FRONTAL BOUNDARY WILL BE
WAVERING ACROSS THE WATERS AND JUST INLAND THROUGH THE PERIOD.
WINDS WILL BE RELATIVELY LIGHT FROM THE NORTHEAST ON SATURDAY AND
VARIABLE IN DIRECTION ON SUNDAY. SEAS ARE EXPECTED TO BE MAINLY
BETWEEN 2 AND 3 FEET.
LONG TERM /SUNDAY THROUGH TUESDAY/...
AS OF 325 PM THURSDAY...STALLED OR NEARLY STALLED OUT FRONTAL
BOUNDARIES ALWAYS MAKE FOR A PROBLEMATIC WIND FORECAST AND SUNDAY
APPEARS TO BE NO DIFFERENT. THERE IS LOW CONFIDENCE AT WHICH THE
SPEED THE BOUNDARY LIFTS TO THE NORTH AND MODEL GUIDANCE KEEPS
WANTING TO SLOW ITS PROGRESS. IT DOES APPEAR THAT A SOUTHERLY
COMPONENT WILL BECOME ESTABLISHED HOWEVER EVEN IF ONLY LATER IN
THE DAY. SPEEDS WILL BE LIGHT HOWEVER KEEPING SEAS NO HIGHER THAN
TH 2 TO 3 FT RANGE. S TO SW WINDS REMAIN LIGHT ON MONDAY AND SEAS
UNCHANGED. A SOUTHERLY COMPONENT REMAINS ON TUESDAY BUT SLIGHT
VARIATION FROM SE TO SW SEEMS POSSIBLE AS THE GRADIENT GETS QUITE
WEAK EVEN BY AUGUST STANDARDS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...SHK/TRA
SHORT TERM...HAWKINS
LONG TERM...MBB/SGL
AVIATION...MRR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1040 AM EDT WED AUG 14 2013
.SYNOPSIS...
A COLD FRONT WILL CONTINUE TO SINK SOUTHWARD THIS AFTERNOON AND
THEN STALL OVER SOUTHERN SOUTH CAROLINA TONIGHT THROUGH FRIDAY...
BEFORE LIFTING BACK NORTH THIS WEEKEND. THIS WILL RESULT IN
SEVERAL PERIODS OF SIGNIFICANT RAINFALL THROUGH THE UPCOMING
WEEKEND. A DRYING AND WARMING TREND IS EXPECTED NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1050 AM WEDNESDAY...THE COLD FRONT IS MAKING PROGRESS TO THE
SOUTH AND THE FRONT IS NEARING WILLIAMSBURG AND GEORGETOWN
COUNTIES AT 14 UTC. THE DEW POINTS ARE NOW IN THE UPPER 60S IN
ROBESON AND BLADEN COUNTIES AND THIS DRIER AIR WILL SLOW BUT MAKE
A BIT FARTHER PUSH TO THE SOUTH. PATCHY SHOWERS ARE BEGINNING TO
MOVE INTO THE NORTHWEST COUNTIES AND THESE WILL CONTINUE OVER THE
NEXT FEW HOURS AS THEY SPREAD EASTWARD. THE 12 UTC HRRR IS SHOWING
THE STRONGEST CONVECTION ALONG THE FRONTAL BOUNDARY WHICH WILL BE
SOUTH OF THE AREA. BUT SOME WEAKER CONVECTION IS FORECASTED TO
DEVELOP ALONG THE COASTAL COUNTIES MAINLY AFTER 18 UTC AND THE
OVER INLAND PORTIONS OF NORTHEAST SOUTH CAROLINA COUNTIES JUST
NORTH OF THE SURFACE BOARDER. TEMPERATURES WILL STRUGGLE BUT
SHOULD SETTLE OUT IN THE LOWER 80S TO NEAR 80 ESPECIALLY IF A
BREAK IN THE CLOUDS DEVELOP.
OVERNIGHT WITH THE COOLER AND DRIER AIR LOWS WILL FALL INTO THE
MID 60S NORTH OF A FLORENCE TO BURGAW LINE AND UPPER 60S TO THE
SOUTH.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 AM WEDNESDAY...AFTER SEVERAL DAYS OF THE GUIDANCE
INSISTING THAT THE COLD FRONT WILL GET HUNG UP OVER THE LOCAL
CWA...IT NOW APPEARS IT WILL GET SHUNTED FAR ENOUGH SOUTHWARD THAT
DRIER AIR IS NOW PROGGED TO WORK INTO THE CWA...ESPECIALLY ACROSS
THE NORTHERN HALF. WHILE THE EXTREME SOUTHERN END OF THE CWA MAY
STILL GET INTO PERIODS OF HEAVY RAINFALL THURSDAY...BUT BOTH LOWER
AND UPPER ATMOSPHERIC PARAMETERS NOW LOOK LESS FAVORABLE FOR
CONVECTION AND HEAVY RAINFALL. THURSDAY WILL NOT BE A "NICE" DAY
ACROSS THE AREA...WITH LOTS OF CLOUDS AND STILL SHOWERS AROUND
THANKS TO SOME DIFFLUENCE ALOFT IN THE FRONT IN THE VICINITY...AND
TEMPS RISING ONLY TO AROUND 80...MAYBE LOW 80S FAR SOUTHERN ZONES.
LOWS THURSDAY NIGHT WILL DROP INTO THE UPPER 60S MOST LOCATIONS.
MOISTURE RETURNS FRIDAY AS THE FRONT BEGINS TO LIFT BACK ACROSS THE
AREA IN RESPONDS TO A 5H LOW CLOSING OFF ACROSS THE TN VLY AND UPPER
RIDGING OVER THE ATLANTIC OCEAN RETROGRADING BACK TOWARDS THE COAST.
THIS TURNS MUCH OF THE MID-LEVEL FLOW TO SOUTHERLY...AND ADVECTS
MORE SIGNIFICANT MOISTURE BACK INTO THE COLUMN. PWATS RISE TO OVER
TWO INCHES ONCE AGAIN...WHILE A STRONG VORT MOVES THROUGH THE TROUGH
AND OVERHEAD FRIDAY. THIS WILL CAUSE INCREASED COVERAGE OF
PRECIP...WITH RENEWED HEAVY RAIN POTENTIAL. THE BEST CHANCE WILL
AGAIN BE THE EASTERN THIRD OF THE CWA...BUT FRIDAY LOOKS LIKE IT
WILL BE AT LEAST MARGINALLY MORE ACTIVE THAN THURSDAY.
SURPRISINGLY...PRECIP TYPE ON FRIDAY COULD BE PRIMARILY SHOWERS OR
STRATIFORM RAIN AS LOW LEVEL FLOW OVERRUNS THE SLOWLY ADVANCING
FRONT. HAVE INCLUDED MENTION OF THUNDER DUE TO SOME UPPER
SUPPORT...BUT SOUNDINGS SUGGEST SOMEWHAT LIMITED INSTABILITY. TEMPS
FRIDAY WILL AGAIN BE HELD IN CHECK BY CLOUDS AND RAIN...RISING ONLY
TO AROUND 80 ACROSS THE CWA. LOWS FRIDAY NIGHT WILL BE A DEGREE OR
TWO WARMER THAN THURSDAY NIGHT AREA-WIDE.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 300 AM WEDNESDAY...THE EXTENDED WILL START OUT QUITE WET...BUT
A DRYING AND WARMING TREND WILL DEVELOP INTO NEXT WEEK.
CUTOFF 5H LOW ACROSS THE TN VLY AND LARGE UPPER BLOCKING RIDGE
ACROSS THE ATLANTIC OCEAN PINCHES THE AREA BETWEEN THE TWO...WITH
DEEP SOUTHERLY FLOW PERSISTING WITHIN THE COLUMN. WHILE THE WEAK
COLD/STATIONARY FRONT WILL BE LIFTING BACK ACROSS THE
AREA...TROPICAL MOISTURE IN THE GULF OF MEXICO WILL BE ADVECTED
NORTHWARD TOWARDS THE AREA. WHILE THIS IS HAPPENING...UPPER RIDGE
WILL BEGIN TO RETROGRADE STRONGLY BACK TOWARDS THE COAST. ALL
THESE TOGETHER POINT TOWARDS SATURDAY BEING VERY WET...BUT THE
HIGHEST RAINFALL TOTALS MAY BE I-95 AND WESTWARD THANKS TO THE
ADVANCING RIDGE. SUN-TUE...RIDGE MOVES EVEN FURTHER WEST AND RIDGE
AXIS IS NO PROGGED TO MAKE IT EVEN WEST OF THE COAST. THIS SHUNTS
THE BEST PRECIP FORCING WEST OF THE LOCAL AREA...AND A
DRYING/WARMING TREND WILL COMMENCE SUNDAY. SUNDAY WILL STILL
FEATURE SCATTERED TO WIDESPREAD CONVECTION...BUT LOWERING POP WITH
TEMPS RISING TO SEASONABLE OR ABOVE-CLIMO LEVELS WILL OCCUR NEXT
WEEK.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
AS OF 12Z...ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS EXPECTED
TODAY AND TONIGHT POTENTIALLY CREATING BRIEF PERIODS OF MVFR/IFR.
AREAS OF FOG MAY CREATE BRIEFLY REDUCED RESTRICTIONS AS WELL.
OTHERWISE EXPECT VFR.
VFR PREVAILS THIS MORNING WITH A FEW LIGHT SHOWERS PUSHING OFF
THE COAST ATTM AS A COLD FRONT CONTINUES TO DROP AND PUSH THROUGH
THE FORECAST AREA THIS MORNING. ANTICIPATE THE FRONTAL PASSAGE TO
SLOWLY PUSH THROUGH THE EARLY AFTERNOON HOURS...BECOMING STALLED
ALONG THE COAST AND ALLOWING FOR WINDS TO VEER FROM SOUTH-
SOUTHWEST TO NORTH- NORTHWEST...TO EVENTUALLY NORTHEAST BY LATER
TODAY. SUSTAINED WINDS OF AOB 12 KTS ARE ANTICIPATED...WITH GUSTS
AROUND 25 KTS POSSIBLE IN ANY STRONG THUNDERSTORMS AS CHANCES
INCREASE FOR ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS
BEHIND THE FRONT. CONFIDENCE IS LOWERED GIVEN
TIMING/LOCATION...THUS HAVE OPTED TO CONTINUE VCSH/VCTS/TEMPO
GROUPS. TONIGHT AND THROUGH THE REMAINDER OF FCST PERIOD...FCST
SOUNDINGS AND TIME-HEIGHT ANALYSIS ARE IN AGREEMENT FOR THE
POSSIBILITY OF MVFR DUE TO LOW CIGS AND AREAS OF PATCHY FOG...THUS
HAVE OPTED TO INTRODUCE MVFR AT THE INLAND SITES AS OF NOW.
NORTHEAST WINDS AOB 10 KTS WILL CONTINUE WITH ISOLATED SHOWERS
POSSIBLE.
EXTENDED OUTLOOK...SHOWERS AND ISOLATED T-STORMS EXPECTED THURSDAY
THROUGH SUNDAY. HEAVY RAINFALL AT TIMES COULD PRODUCE LOCALIZED
PERIODS OF MVFR/IFR/LIFR.
&&
.MARINE...
NEAR TERM/THROUGH TONIGHT/...
AS OF 1050 AM WEDNESDAY...THE COLD FRONT IS PUSHING THROUGH THE
COASTAL WATERS THIS MORNING AND WILL STALL TO THE SOUTH AND EAST
OF OUR WATERS THE SMALL CRAFT EXERCISE CAUTION CONTINUES AS SEAS
CONTINUE AT ROUGH 3 TO 5 FEET ESPECIALLY 10 MILES AND FARTHER OFF
THE COAST.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 AM WEDNESDAY...COLD FRONT SOUTH OF THE WATERS LEAVES
GUSTY NE WINDS IN ITS WAKE...WITH SPEEDS OF 15-20 KTS
THURSDAY...FALLING TO 10-15 KTS FRIDAY...AND THEN EVEN LIGHTER
LATE FRIDAY AS THE FRONT SLOWLY LIFTS BACK NORTH ACROSS THE
WATERS. WAVE HEIGHTS WILL BE PRIMARILY FORMED BY A E/NE WIND
CHOP...THUS THE HIGHEST SEAS WILL BE ON THURSDAY WITH SIGNIFICANT
HEIGHTS OF 3-5 FT...FALLING TO 2-3 FT ON FRIDAY. A SMALL CRAFT
EXERCISE CAUTION HAS BEEN ISSUED FOR ALL THE WATERS THROUGH
THURSDAY DUE TO THE STRONG WINDS AND HIGH SEAS...BUT WILL EXPIRE
DURING THURSDAY NIGHT AS CONDITIONS IMPROVE.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 300 AM WEDNESDAY...STALLED BOUNDARY OVER THE WATERS WILL PUSH
NORTHWARD ON SATURDAY...EVENTUALLY CLEARLY THE WATERS AND LEAVING
INCREASING SOUTHERLY WINDS ON SUNDAY. WHILE WINDS INITIALLY WILL
QUITE LIGHT...5-10 KTS OF VARIABLE DIRECTION...THEY WILL SLOWLY
BECOME S/SE LATE SATURDAY AND SUNDAY...AT AROUND 10 KTS. SEAS WILL
BE 2-3 FT THROUGH THE PERIOD...WITH A SOUTHERLY WIND WAVE BECOMING
DOMINANT SUNDAY.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JDW
NEAR TERM...DRH
SHORT TERM...JDW
LONG TERM...JDW
AVIATION...SGL
AREA FORECAST DISCUSSION
NWS TULSA OK
902 PM CDT THU AUG 15 2013
.DISCUSSION...
MCS OVER SOUTH CENTRAL KANSAS IS ABOUT TO PUSH INTO NORTHERN
OKLAHOMA THIS EVENING. THE SYSTEM IS NO LONGER SEVERE...WITH THE
STRONGEST MEASURED WIND OVER THE PAST HOUR OR SO AT 35 MPH. THE
PRIMARY MECHANISM DRIVING THIS SYSTEM IS THE COLD POOL LIFTING
MODERATELY UNSTABLE AIR ON THE ORDER OF 1000-2000 J/KG OF
MLCAPE...AND THIS INSTABILITY IS PRIMARILY CONFINED WEST OF
HIGHWAY 75. AN 850MB RIDGE RESIDES OVER EASTERN OKLAHOMA...SO
THERE IS NOT THAT TYPICAL LOW LVL JET FEEDING INTO THIS SYSTEM.
THEREFORE...THE MCS WILL CONTINUE SOUTH...MAINLY TO THE WEST OF
HIGHWAY 75 WHERE THE INSTABILITY IS...AND LIKELY WEAKEN WITH TIME AS
WE GO INTO THE NIGHT AS THE HRRR MODEL SUGGESTS. UPDATED PRODUCTS
HAVE BEEN SENT.
LACY
&&
.PREV DISCUSSION... /ISSUED 645 PM CDT THU AUG 15 2013/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
MCS IS CURRENTLY PUSHING SOUTHWARD THROUGH EASTERN KANSAS AND
LOOKS TO REMAIN ORGANIZED ENOUGH TO REACH NORTHEAST OKLAHOMA
AROUND 01Z. THUS...WILL ADD VCTS TO BVO/TUL/RVS FOR A FEW HOURS
THIS EVENING. ACROSS THE REST OF THE REGION...PARTLY CLOUDY SKIES
SHOULD REMAIN COMMON THROUGH THE PERIOD. LIGHT WINDS SHOULD ALSO
CONTINUE THROUGH THE PERIOD. VFR CONDITIONS SHOULD REMAIN AT ALL
TAF SITES THROUGH THE PERIOD WITH POSSIBLE MVFR CONDITIONS WITHIN
THE MCS THIS EVENING OVER NORTHEAST OKLAHOMA.
PREV DISCUSSION... /ISSUED 357 PM CDT THU AUG 15 2013/
DISCUSSION...
NUMERICAL MODELS DIFFER ON HOW MUCH... IF ANY
CONVECTION REACHES EASTERN OKLAHOMA OVERNIGHT.
ECMWF AND ESPECIALLY LATEST H R CUBED BULLISH
WITH PRECIP INTO EASTERN OKLAHOMA...PRIMARILY
FROM AROUND TULSA ON NORTHWEST. GIVEN CURRENT
CONVECTION OVER KANSAS..RATHER CONFIDENT AREA
NORTH AND WEST OF TULSA WILL GET WET TONIGHT.
MUCH LESS CONFIDENT HOW MUCH PRECIP LEFT OVER
FRIDAY MORNING IN EASTERN OK.
UPPER FLOW TURNS FROM NORTHWEST TO NORTH NEXT
24 HOURS KEEPING OUR STRING NICE BELOW NORMAL
TEMPS GOING WELL INTO NEXT WEEK. BORING...BUT
NICE. GW
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 63 84 63 87 / 40 20 10 0
FSM 62 85 63 89 / 10 10 10 0
MLC 62 84 61 89 / 20 20 10 0
BVO 61 82 59 85 / 60 20 0 0
FYV 54 81 56 83 / 10 10 10 0
BYV 56 79 58 82 / 0 10 10 0
MKO 60 84 61 87 / 20 20 10 0
MIO 59 81 59 83 / 20 10 0 0
F10 62 83 62 87 / 30 20 10 0
HHW 62 87 63 89 / 10 20 10 0
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
LONG TERM....30
AREA FORECAST DISCUSSION
NWS NORMAN OK
1116 PM CDT TUE AUG 13 2013
.AVIATION...
06Z TAFS... MVFR/VFR CEILINGS EXPECTED THROUGH THE PERIOD.
HOWEVER... IFR CEILINGS ALONG WITH PATCHY FOG COULD BE POSSIBLE
AT A FEW SITES NORTHERN/WESTERN OK. SCATTERED SHOWERS/STORMS WILL
BE POSSIBLE ACROSS PARTS OF WESTERN/SOUTHERN OK AND NORTH TEXAS
WED AFTN. STRONG VARIABLE WINDS WILL BE POSSIBLE NEAR ANY STORMS.
&&
.PREV DISCUSSION... /ISSUED 946 PM CDT TUE AUG 13 2013/
UPDATE...
REDUCED RAIN CHANCES ACROSS MUCH OF THE AREA FOR THE REST OF
TONIGHT. ADDED PATCHY FOG MENTION ACROSS THE NORTHWEST HALF OF
OKLAHOMA LATER TONIGHT INTO WEDNESDAY MORNING.
DISCUSSION...
RAIN CHANCES HAVE DIMINISHED FOR NOW. THEY MAY INCREASE AFTER 3
AM NEAR AND SOUTH OF THE RED RIVER.
BAND OF SHOWERS FROM WEATHERFORD TO STILLWATER CONTINUES TO
DIMINISH. GENERALLY...EXPECT THIS TREND TO CONTINUE. KEPT 20
TO 40 PERCENT RAIN CHANCES IN THESE AREAS.
LATEST HRRR/RAP13 SUGGESTS THAT A FEW MORE SHOWERS AND STORMS MAY
DEVELOP NEAR AND SOUTH OF THE RED RIVER AFTER 3 PM TONIGHT WHERE
DEEPER MOISTURE AND INSTABILITY EXIST. KEPT 20 TO 30 PERCENT
CHANCES IN THESE AREAS. NO SEVERE STORMS ARE EXPECTED...THOUGH
LOCALLY HEAVY DOWNPOURS MAY BE POSSIBLE.
FOG MAY BE A CONCERN LATE TONIGHT INTO WEDNESDAY MORNING WITH
MOIST UPSLOPE FLOW PARTICULARLY OVER NORTHWEST OKLAHOMA. ADDED
PATCHY FOG MENTION DUE TO MODERATE CONFIDENCE OF OCCURRENCE.
WIDESPREAD DENSE FOG REMAINS UNLIKELY.
PRODUCTS HAVE BEEN UPDATED.
MBS
PREV DISCUSSION... /ISSUED 629 PM CDT TUE AUG 13 2013/
AVIATION...
0Z TAFS... SHOWERS/STORMS WILL AFFECT KPNC THIS EVENING. THIS
ACTIVITY MAY MAKE IT AS FAR SOUTH AS KOKC/KOUN BUT CHANCES TOO LOW
FOR MENTION ATTM. SHOWERS/STORMS WILL BE POSSIBLE AGAIN WED AFTN
ACROSS PARTS OF SOUTHERN/WESTERN OK AND NORTH TEXAS BUT CHANCES
ALSO TOO LOW AT SOME SITES FOR MENTION IN TAF. SOME IFR CEILINGS
COULD DEVELOP OVERNIGHT IN SOME LOCATIONS, OTHERWISE VFR/MVFR
CONDITIONS EXPECTED.
PREV DISCUSSION... /ISSUED 603 PM CDT TUE AUG 13 2013/
UPDATE...
INCREASED RAIN CHANCES THROUGH 10 PM THIS EVENING ACROSS FAR
NORTHERN OKLAHOMA...AND DECREASED THEM ELSEWHERE.
DISCUSSION...
SHOWERS AND A FEW THUNDERSTORMS WITH LOCALLY HEAVY
RAINFALL OF 1 TO 2 INCHES MAY OCCUR THIS EVENING ACROSS
FAR NORTHERN OKLAHOMA...NORTH OF A FREEDOM TO FAIRVIEW TO
STILLWATER LINE. THIS COMPLEX CONTINUES TO SLOWLY DRIFT
SOUTH...BUT SHOULD WEAKEN OVER NEXT FEW HOURS DUE TO THE
LOSS OF DAYTIME HEATING. THESE STORMS SHOULD STAY BELOW
SEVERE LIMITS DUE TO WEAK INSTABILITY. LATEST MODELS HAVE BEEN
MISHANDLING THIS COMPLEX...EXCEPT FOR THE HRRR WHICH SUGGESTS
THESE STORMS WILL QUICKLY DIMINISH AROUND SUNSET.
STORMS HAVE DIMINISHED ACROSS WESTERN NORTH TEXAS. THERE IS
CHANCE THAT A FEW ADDITIONAL STORMS DEVELOP OR MOVE INTO THESE
AREAS FROM THE WEST OVER THE NEXT SEVERAL HOURS.
ACROSS THE REST OF THE AREA...KEPT A 20 PERCENT CHANCE FOR
STORMS TONIGHT. WITHOUT A STRONG FOCUS TO PROVIDE LIFT...BELIEVE
MOST PLACES WILL REMAIN DRY. MAY UPDATE LATER THIS EVENING
TO ADJUST RAIN CHANCES DOWNWARD.
PRODUCTS HAVE BEEN UPDATED.
MBS
PREV DISCUSSION... /ISSUED 344 PM CDT TUE AUG 13 2013/
DISCUSSION...
MAIN AREA OF CONVECTION OVER CENTRAL/SOUTH CENTRAL
KANSAS WILL CONTINUE TO DRIFT SOUTH AND SOUTHEAST
THIS AFTERNOON AND EARLY EVENING. STORMS SHOULD
GRADUALLY DECREASE IN COVERAGE AND INTENSITY
BY THE EARLY EVENING.
OTHER STORMS HAVE FORMED ACROSS NORTH TEXAS AND THE SOUTHERN
TEXAS PANHANDLE WHERE TEMPERATURES HAVE WARMED INTO THE LOWER AND
MID 90S. A FEW STRONG STORMS WILL BE POSSIBLE THROUGH THE LATE
AFTERNOON/EARLY EVENING WITH STRONG WINDS AND HEAVY RAINFALL
THE MAIN HAZARDS.
THE CENTER OF HIGH PRESSURE AND DRIER AIR WILL BUILD FROM THE
NORTHERN PLAINS INTO THE UPPER MIDWEST/MID MISSISSIPPI VALLEY
TONIGHT INTO WEDNESDAY. THIS WILL FILTER DRIER AIR INTO NORTHERN
AND EASTERN PARTS OF THE FA...AND DECREASE RAIN CHANCES IN THE
SHORT TERM.
A COUPLE OF WAVES WILL MOVE THROUGH A NORTH TO NORTHWEST
FLOW THURSDAY INTO EARLY FRIDAY. THIS WILL BRING AN
INCREASE IN SHOWER AND STORM CHANCES DURING THIS
PERIOD...ESPECIALLY ACROSS THE NORTHERN HALF OF
OKLAHOMA.
MAINLY DRY CONDITIONS ARE EXPECTED OVER THE WEEKEND AS
AN UPPER RIDGE BUILDS SLOWLY EAST. BY EARLY NEXT WEEK...
THE GFS IN MORE AGGRESSIVE IN WEAKENING THE RIDGE AS
ANOTHER TROUGH MOVES ACROSS THE NORTHERN AND CENTRAL
ROCKIES. THIS WOULD PROVIDE ANOTHER OPPORTUNITY FOR
SHOWERS AND STORMS. THE EC HOLDS MORE RIDGING ALOFT
ACROSS THE SOUTHERN PLAINS. FOR NOW WILL MAINTAIN
A DRY FORECAST WITH VERY WARM/HOT TEMPS.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 70 83 67 84 / 20 20 10 20
HOBART OK 69 86 69 86 / 20 30 20 20
WICHITA FALLS TX 73 89 72 89 / 20 40 20 30
GAGE OK 64 82 66 85 / 10 20 30 30
PONCA CITY OK 64 82 64 83 / 20 10 10 20
DURANT OK 72 87 67 88 / 10 40 10 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
17/25/25
AREA FORECAST DISCUSSION
NWS ABERDEEN SD
321 PM CDT WED AUG 14 2013
.SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT
PRETTY QUIET ACROSS THE CWA THIS AFTERNOON BUT WILL BE WATCHING
THE WESTERN CWA OVER THE NEXT FEW HOURS FOR THE POTENTIAL FOR A
FEW ISOLD THUNDERSHOWERS AS SHORTWAVE ENERGY APPROACHES FROM THE
MIDWEST. BEST SUPPORT DOES NOT ARRIVE UNTIL LATER THIS
EVENING...BUT DAYTIME HEATING ACROSS THE WESTERN CWA HAS ALLOWED
MLCAPE TO APPROACH 1000 J/KG. SHEAR IS LACKING ONCE AGAIN AS HAS
BEEN THE CASE THE PAST FEW DAYS. CURRENTLY SEEING A CONGESTED CU
FIELD ACROSS NORTH CENTRAL SD WITH RADAR ECHOES JUST BEGINNING TO
INCREASE OVER CORSON COUNTY. HRRR ACTUALLY PICKING UP ON THIS AND
SHOWING A FEW POPCORN TYPE LIGHT SHOWERS OR MAYBE A MODERATE
THUNDERSHOWER THROUGH LATE AFTERNOON. WILL MAINTAIN SLIGHT CHANCE
POPS FOR THE WESTERN CWA THROUGH THE AFTERNOON. MAIN SHORTWAVE
ENERGY APPROACHES THE REGION LATER THIS EVENING...BUT MODELS NOT
TOO IMPRESSED WITH THIS FOR OUR CWA. 12Z NSSL WRF SHOWS A LINE OF
SHOWERS AND STORMS MOVING INTO WESTERN SD LATER THIS EVENING BUT
DIES OUT AS ITS ENTERING THE WESTERN CWA. WILL MAINTAIN SMALL POPS
OVERNIGHT AS WELL...BUT HAVE TRIMMED THINGS DOWN TO DRY FOR THE
EASTERN CWA AS THERE JUST DOESNT SEEM TO BE ANY SUPPORT FOR
PRECIP. THERE REALLY IS NO LOW LEVEL JET TO SPEAK OF OVERNIGHT
EITHER.
WEAK SHORTWAVE ENERGY MOVES SOUTHEAST OVER THE AREA ON THURSDAY
BUT MODELS KEEP TRENDING DRIER AND DRIER FOR THIS...TO THE POINT
NOW WHERE MOST MODELS ARENT EVEN SHOWING ANY PRECIP FOR THE AREA.
HAVE SCALED BACK POPS QUITE A BIT...GOING DRY IN PLACES BUT
KEEPING A SLIGHT CHANCE GOING FOR MOST PLACES. AFTER
THURSDAY...THE WARM UP BEGINS AS UPPER RIDGING BUILDS OVER THE
HIGH PLAINS AND DAKOTAS.
.LONG TERM...SATURDAY THROUGH WEDNESDAY
MAIN CHALLENGE IN THE LONG TERM WILL BE PRECIP CHANCES UNDER THE
DOMINANT UPPER RIDGE.
MODELS ARE NOT IN GOOD AGREEMENT TODAY IN THE EXTENDED. TOSSED OUT
THE GEM AS IT IS THE ONLY MODEL SHOWING A DEVELOPING TROPICAL
SYSTEM IN THE GULF THIS WEEKEND. THIS MAY CONTAMINATE QPF AND
PRESSURE FIELDS ALL THE WAY NORTH INTO THE DAKOTAS. GFS AND ECMWF
ARE BOTH FLIP FLOPPING WITH MOISTURE FIELDS THOUGH SFC PRESSURE
PROGS ARE SIMILAR. BOTH MODELS SHOW TWO TROFS MOVING ACROSS THE
DAKOTAS...ONE SUNDAY NIGHT/MONDAY AND ANOTHER TUESDAY
NIGHT/WEDNESDAY. HOWEVER THE GFS IS WET FOR THE FIRST AND DRY FOR
THE SECOND WHILE THE ECMWF IS OPPOSITE. STUCK WITH ALLBLEND POPS
SUNDAY NIGHT/MONDAY AS 30S/40S SEEM REASONABLE AT THIS POINT. WENT
DRIER THAN ALLBLEND FOR THE END OF THE PERIOD BASED ON INTER
OFFICE COLLABORATION.
TEMPERATURES SHOULD BE ON THE RISE THROUGH THE PERIOD WITH HIGHS
IN THE UPPER 80S TO LOWER 90S EXPECTED.
&&
.AVIATION...
18Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
VFR CONDITIONS WILL PREVAIL FOR ALL TERMINALS THROUGH THIS
EVENING. ISOLATED SHOWERS AND TSTORMS ARE POSSIBLE OVERNIGHT NEAR
KPIR. THIS ADDED MOISTURE WILL LIKELY RESULT IN LIGHT FOG
DEVELOPMENT CAUSING MVFR CIGS/VSBY. MVFR CONDITIONS SHOULD LIFT TO
VFR THURSDAY MORNING.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
SHORT TERM...TMT
LONG TERM...WISE
AVIATION...WISE
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS MORRISTOWN TN
945 AM EDT WED AUG 14 2013
.DISCUSSION...
A COLD FRONT TO OUR SOUTH AND STRONG HIGH PRESSURE OVER THE GREAT
LAKES REGION WILL PROVIDE A VERY PLEASANT DAY FOR MID-AUGUST
ACROSS THE AREA. AFTERNOON DEWPOINTS WILL FALL INTO THE 50S WITH
DAYTIME MIXING...WITH HIGH TEMPS IN THE UPPER 70S TO LOWER 80S IN
MOST SPOTS. THE CURRENT FORECAST HAS A SLIGHT CHANCE POP IN SW NC.
WHILE THE NAM DOES SHOW SOME DEVELOPMENT IN THE NC MTNS AND UPSTATE
SC THIS AFTERNOON IN A LOW LEVEL CONVERGENCE ZONE...THE RUC SOUNDING
AT RHP LOOKS VERY STABLE. EXPECT THAT ANY SHOWERS THAT DEVELOP WILL
STAY TO OUR SOUTH AND EAST. WILL UPDATE TO REMOVE POPS IN THIS
AREA...OTHERWISE NO CHANGES ARE NEEDED.
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DGS
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
945 PM CDT THU AUG 15 2013
.UPDATE...
SEVERE THREAT CONTINUES TO DIMINISH AS IT APPEARS THAT MOST OF THE
CONVECTIVE ACTIVITY WILL REMAIN EAST OF THE PANHANDLES. LOW LEVEL
JET...AND ASSOCIATED INCREASE IN CONVECTIVE ACTIVITY HAS YET TO
MATERIALIZE...THUS HAVE CANCELED THE REMAINDER OF THE WATCH. HAVE
ALSO DECREASED POPS ACROSS THE PANHANDLES TO 20 TO 30 PERCENT.
JOHNSON
&&
.PREV DISCUSSION... /ISSUED 814 PM CDT THU AUG 15 2013/
UPDATE...
WINDOW OF RISK OF SEVERE WEATHER IS DIMINISHING...EXCEPT IN THE
EASTERN OK AND NE TX PANHANDLE WHICH MAY YET SEE STORMS DEVELOP IN
RESPONSE TO A DEVELOPING WEAK LOW LEVEL JET. THUS...WILL KEEP THE
WATCH GOING IN BEAVER...LIPSCOMB...OCHILTREE...AND HEMPHILL
COUNTIES...BUT HAVE CANCELED THE WATCH FOR THE REMAINDER OF THE TX
PANHANDLE.
JOHNSON
PREV DISCUSSION... /ISSUED 710 PM CDT THU AUG 15 2013/
AVIATION...DISCUSSION FOR 00Z TAFS
MAINLY VFR TAFS SHOULD PREVAIL THOUGH THERE ARE A FEW POTENTIALLY
AMENDABLE FEATURES OF NOTE. FIRST...SCT SHOWERS AND STORMS COULD
AFFECT ANY OF THE 3 TAF SITES THIS EVENING INTO POSSIBLY THE FIRST
FEW HOURS OF FRIDAY MORNING. HOWEVER...CONFIDENCE IS NOT HIGH ENOUGH
TO INCLUDE ANY MENTION AT THIS TIME. SECOND...A FEW LOW CLOUDS AND/OR
REDUCED VISIBILITIES WILL BE POSSIBLE AT ANY OF THE SITES FROM
16/10Z-16/15Z. WINDS WILL GENERALLY BE LIGHT THROUGH THE PERIOD
OUTSIDE OF ANY THUNDERSTORMS.
SIMPSON
PREV DISCUSSION... /ISSUED 326 PM CDT THU AUG 15 2013/
DISCUSSION...
LITTLE OR NO CHANGES TO THE PREVIOUS GRIDS AND FORECAST AS THE
WEATHER PATTERN DOES NOT CHANGE MUCH. UPPER HIGH OVER THE FOUR
CORNERS AND SOUTHWESTERN STATES THROUGH THE WEEKEND WILL MAINTAIN A
NORTHWESTERLY UPPER FLOW TONIGHT...TRANSITIONING TO NORTHERLY BY
FRIDAY NIGHT AND SATURDAY. LOOKING AT THE TTU-WRF...NAM...GFS...AND
ECMWF...BETTER ORGANIZED CONVECTION COULD POSSIBLY HOLD OFF UNTIL
AROUND 00Z FRIDAY OR LATER. THE LATEST HRRR DEVELOPS CONVECTION
ACROSS THE NORTHWEST SECTIONS OF THE FORECAST AREA BY 20Z TODAY WHICH
THEN MOVES SOUTHEAST ACROSS THE WESTERN AND CENTRAL TEXAS PANHANDLE
AROUND 22Z TODAY TO AROUND 00Z TO 02Z FRIDAY. SINCE NOT MUCH
DEVELOPING AS OF 20Z TODAY ACROSS THE PANHANDLES...THINKING THAT THE
HRRR MAY BE THE ODD MODEL OUT. CONVECTION CURRENTLY OVER OKLAHOMA AND
EAST CENTRAL NEW MEXICO MOVING SOUTH AND SOUTHEAST. WILL CONTINUE TO
MONITOR TRENDS...BUT WITH CAPES FORECAST TO BE IN THE 1500 TO 2500
J/KG RANGE AND SURFACE DEW POINTS IN THE 60S...CANNOT RULE OUT
CONVECTION DEVELOPING PRIOR TO 00Z FRIDAY.
AS THE UPPER HIGH BROADENS OVER THE SOUTHWESTERN STATES OVER THE
WEEKEND...THE UPPER FLOW TRANSITIONS TO NORTHERLY AND EVEN
NORTHEASTERLY BRINGING A GRADUAL END TO THE CONVECTION BY SUNDAY.
WARMER AND DRIER CONDITIONS SUNDAY THROUGH NEXT WEDNESDAY WITH HIGHS
CLIMBING BACK UP INTO THE 90S.
SCHNEIDER
FIRE WEATHER...
AN UPPER RIDGE ACROSS THE FOUR CORNERS REGION AND THE SOUTHWESTERN
STATES WILL MAINTAIN A NORTHWESTERLY TO NORTHERLY UPPER FLOW ACROSS
THE PANHANDLES THROUGH THE WEEKEND. SHOWERS AND THUNDERSTORMS WILL
DEVELOP ACROSS SOUTHEASTERN AND EASTERN COLORADO AND WESTERN AND
SOUTHWESTERN KANSAS LATER TODAY AND TONIGHT AND WILL MOVE SOUTHEAST
ACROSS THE PANHANDLES. NO ELEVATED OR CRITICAL FIRE WEATHER
CONDITIONS ARE EXPECTED THROUGH THE MIDDLE OF NEXT WEEK AS MINIMUM
AFTERNOON RELATIVE HUMIDITIES REMAIN AT OR ABOVE 20 PERCENT THROUGH
THE MIDDLE OF NEXT WEEK.
SCHNEIDER
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
09/16
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
814 PM CDT THU AUG 15 2013
.UPDATE...
WINDOW OF RISK OF SEVERE WEATHER IS DIMINISHING...EXCEPT IN THE
EASTERN OK AND NE TX PANHANDLE WHICH MAY YET SEE STORMS DEVELOP IN
RESPONSE TO A DEVELOPING WEAK LOW LEVEL JET. THUS...WILL KEEP THE
WATCH GOING IN BEAVER...LIPSCOMB...OCHILTREE...AND HEMPHILL
COUNTIES...BUT HAVE CANCELED THE WATCH FOR THE REMAINDER OF THE TX
PANHANDLE.
JOHNSON
&&
.PREV DISCUSSION... /ISSUED 710 PM CDT THU AUG 15 2013/
AVIATION...DISCUSSION FOR 00Z TAFS
MAINLY VFR TAFS SHOULD PREVAIL THOUGH THERE ARE A FEW POTENTIALLY
AMENDABLE FEATURES OF NOTE. FIRST...SCT SHOWERS AND STORMS COULD
AFFECT ANY OF THE 3 TAF SITES THIS EVENING INTO POSSIBLY THE FIRST
FEW HOURS OF FRIDAY MORNING. HOWEVER...CONFIDENCE IS NOT HIGH ENOUGH
TO INCLUDE ANY MENTION AT THIS TIME. SECOND...A FEW LOW CLOUDS AND/OR
REDUCED VISIBILITIES WILL BE POSSIBLE AT ANY OF THE SITES FROM
16/10Z-16/15Z. WINDS WILL GENERALLY BE LIGHT THROUGH THE PERIOD
OUTSIDE OF ANY THUNDERSTORMS.
SIMPSON
PREV DISCUSSION... /ISSUED 326 PM CDT THU AUG 15 2013/
DISCUSSION...
LITTLE OR NO CHANGES TO THE PREVIOUS GRIDS AND FORECAST AS THE
WEATHER PATTERN DOES NOT CHANGE MUCH. UPPER HIGH OVER THE FOUR
CORNERS AND SOUTHWESTERN STATES THROUGH THE WEEKEND WILL MAINTAIN A
NORTHWESTERLY UPPER FLOW TONIGHT...TRANSITIONING TO NORTHERLY BY
FRIDAY NIGHT AND SATURDAY. LOOKING AT THE TTU-WRF...NAM...GFS...AND
ECMWF...BETTER ORGANIZED CONVECTION COULD POSSIBLY HOLD OFF UNTIL
AROUND 00Z FRIDAY OR LATER. THE LATEST HRRR DEVELOPS CONVECTION
ACROSS THE NORTHWEST SECTIONS OF THE FORECAST AREA BY 20Z TODAY WHICH
THEN MOVES SOUTHEAST ACROSS THE WESTERN AND CENTRAL TEXAS PANHANDLE
AROUND 22Z TODAY TO AROUND 00Z TO 02Z FRIDAY. SINCE NOT MUCH
DEVELOPING AS OF 20Z TODAY ACROSS THE PANHANDLES...THINKING THAT THE
HRRR MAY BE THE ODD MODEL OUT. CONVECTION CURRENTLY OVER OKLAHOMA AND
EAST CENTRAL NEW MEXICO MOVING SOUTH AND SOUTHEAST. WILL CONTINUE TO
MONITOR TRENDS...BUT WITH CAPES FORECAST TO BE IN THE 1500 TO 2500
J/KG RANGE AND SURFACE DEW POINTS IN THE 60S...CANNOT RULE OUT
CONVECTION DEVELOPING PRIOR TO 00Z FRIDAY.
AS THE UPPER HIGH BROADENS OVER THE SOUTHWESTERN STATES OVER THE
WEEKEND...THE UPPER FLOW TRANSITIONS TO NORTHERLY AND EVEN
NORTHEASTERLY BRINGING A GRADUAL END TO THE CONVECTION BY SUNDAY.
WARMER AND DRIER CONDITIONS SUNDAY THROUGH NEXT WEDNESDAY WITH HIGHS
CLIMBING BACK UP INTO THE 90S.
SCHNEIDER
FIRE WEATHER...
AN UPPER RIDGE ACROSS THE FOUR CORNERS REGION AND THE SOUTHWESTERN
STATES WILL MAINTAIN A NORTHWESTERLY TO NORTHERLY UPPER FLOW ACROSS
THE PANHANDLES THROUGH THE WEEKEND. SHOWERS AND THUNDERSTORMS WILL
DEVELOP ACROSS SOUTHEASTERN AND EASTERN COLORADO AND WESTERN AND
SOUTHWESTERN KANSAS LATER TODAY AND TONIGHT AND WILL MOVE SOUTHEAST
ACROSS THE PANHANDLES. NO ELEVATED OR CRITICAL FIRE WEATHER
CONDITIONS ARE EXPECTED THROUGH THE MIDDLE OF NEXT WEEK AS MINIMUM
AFTERNOON RELATIVE HUMIDITIES REMAIN AT OR ABOVE 20 PERCENT THROUGH
THE MIDDLE OF NEXT WEEK.
SCHNEIDER
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
09/16
AREA FORECAST DISCUSSION
NWS AMARILLO TX
710 PM CDT THU AUG 15 2013
.AVIATION...DISCUSSION FOR 00Z TAFS
MAINLY VFR TAFS SHOULD PREVAIL THOUGH THERE ARE A FEW POTENTIALLY
AMENDABLE FEATURES OF NOTE. FIRST...SCT SHOWERS AND STORMS COULD
AFFECT ANY OF THE 3 TAF SITES THIS EVENING INTO POSSIBLY THE FIRST
FEW HOURS OF FRIDAY MORNING. HOWEVER...CONFIDENCE IS NOT HIGH ENOUGH
TO INCLUDE ANY MENTION AT THIS TIME. SECOND...A FEW LOW CLOUDS AND/OR
REDUCED VISIBILITIES WILL BE POSSIBLE AT ANY OF THE SITES FROM
16/10Z-16/15Z. WINDS WILL GENERALLY BE LIGHT THROUGH THE PERIOD
OUTSIDE OF ANY THUNDERSTORMS.
SIMPSON
&&
.PREV DISCUSSION... /ISSUED 326 PM CDT THU AUG 15 2013/
DISCUSSION...
LITTLE OR NO CHANGES TO THE PREVIOUS GRIDS AND FORECAST AS THE
WEATHER PATTERN DOES NOT CHANGE MUCH. UPPER HIGH OVER THE FOUR
CORNERS AND SOUTHWESTERN STATES THROUGH THE WEEKEND WILL MAINTAIN A
NORTHWESTERLY UPPER FLOW TONIGHT...TRANSITIONING TO NORTHERLY BY
FRIDAY NIGHT AND SATURDAY. LOOKING AT THE TTU-WRF...NAM...GFS...AND
ECMWF...BETTER ORGANIZED CONVECTION COULD POSSIBLY HOLD OFF UNTIL
AROUND 00Z FRIDAY OR LATER. THE LATEST HRRR DEVELOPS CONVECTION
ACROSS THE NORTHWEST SECTIONS OF THE FORECAST AREA BY 20Z TODAY WHICH
THEN MOVES SOUTHEAST ACROSS THE WESTERN AND CENTRAL TEXAS PANHANDLE
AROUND 22Z TODAY TO AROUND 00Z TO 02Z FRIDAY. SINCE NOT MUCH
DEVELOPING AS OF 20Z TODAY ACROSS THE PANHANDLES...THINKING THAT THE
HRRR MAY BE THE ODD MODEL OUT. CONVECTION CURRENTLY OVER OKLAHOMA AND
EAST CENTRAL NEW MEXICO MOVING SOUTH AND SOUTHEAST. WILL CONTINUE TO
MONITOR TRENDS...BUT WITH CAPES FORECAST TO BE IN THE 1500 TO 2500
J/KG RANGE AND SURFACE DEW POINTS IN THE 60S...CANNOT RULE OUT
CONVECTION DEVELOPING PRIOR TO 00Z FRIDAY.
AS THE UPPER HIGH BROADENS OVER THE SOUTHWESTERN STATES OVER THE
WEEKEND...THE UPPER FLOW TRANSITIONS TO NORTHERLY AND EVEN
NORTHEASTERLY BRINGING A GRADUAL END TO THE CONVECTION BY SUNDAY.
WARMER AND DRIER CONDITIONS SUNDAY THROUGH NEXT WEDNESDAY WITH HIGHS
CLIMBING BACK UP INTO THE 90S.
SCHNEIDER
FIRE WEATHER...
AN UPPER RIDGE ACROSS THE FOUR CORNERS REGION AND THE SOUTHWESTERN
STATES WILL MAINTAIN A NORTHWESTERLY TO NORTHERLY UPPER FLOW ACROSS
THE PANHANDLES THROUGH THE WEEKEND. SHOWERS AND THUNDERSTORMS WILL
DEVELOP ACROSS SOUTHEASTERN AND EASTERN COLORADO AND WESTERN AND
SOUTHWESTERN KANSAS LATER TODAY AND TONIGHT AND WILL MOVE SOUTHEAST
ACROSS THE PANHANDLES. NO ELEVATED OR CRITICAL FIRE WEATHER
CONDITIONS ARE EXPECTED THROUGH THE MIDDLE OF NEXT WEEK AS MINIMUM
AFTERNOON RELATIVE HUMIDITIES REMAIN AT OR ABOVE 20 PERCENT THROUGH
THE MIDDLE OF NEXT WEEK.
SCHNEIDER
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
09/16
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1221 PM CDT WED AUG 14 2013
.AVIATION...
AFTN SHRA AND TSRA LIKELY TO BE TOO SCATTERED TO CONFIDENTLY PUT A
TEMPO GROUP IN EITHER TAF...BUT THERE WILL BE SOME AROUND...
POSSIBLY BUILDING SWD FROM AN AREA OF SCATTERED TSRA CURRENTLY
ACROSS THE WRN PANHANDLE. FOCUS THEN SHIFTS TO LATE EVENING WITH
POTENTIAL FOR ANOTHER TS COMPLEX MOVING OUT OF NERN NM. CONFIDENCE
HIGH ENOUGH OF THIS POSSIBLITY TO CONTINUE RUNNING WITH A PROB30
IN BOTH TAFS. SOME CHANCE ON CIG RESTRICTIONS TOWARD SUNRISE
DEPENDING A LOT ON WHETHER THIS LATTER COMPLEX DEVELOPS AND MOVES
THROUGH THE FCST AREA. ATTM WILL MAINTAIN MORE OPTIMISTIC FCST
WITH CIGS IN VFR CATEGORY.
&&
.PREV DISCUSSION... /ISSUED 1113 AM CDT WED AUG 14 2013/
UPDATE...
MINOR UPDATE TO BE ISSUED MAINLY TO CATCH UP TO DIURNAL TRENDS.
LINGERING LIGHT RAIN IN THE SOUTH SHOULD QUICKLY DISSIPATE...BUT A
NARROW BAND OF ISOLATED SHOWERS AND THUNDERSTORMS ALREADY
DEVELOPING ACROSS THE WRN PANHANDLE IN AN AREA OF MOIST UPSLOPE
FLOW. THE HRRR SEEMS TO PICK UP ON THIS TREND THE BEST AND
GENERALLY LEAVES IT AS A DISORGANIZED AREA OF ISOLATED TO
SCATTERED CONVECTION. THIS MODELS FOCUS FOR ORGANIZED CONVECTION
IS AGAIN WITH CONVECTION PROGGED TO DEVELOP ACROSS NERN NM. UPPER
FLOW AGAIN PROGGED TO BE RELATIVELY ROBUST FOR THIS TIME OF
YEAR...ON THE ORDER OF 25-35 KTS AT 500 MB...WITH MODEST BUT MOIST
LOW LEVEL EASTERLY COMPONENT TO THE WINDS. PROGGED LOW LEVEL
THETA-E AXIS LATE THIS AFTN THROUGH THE EVENING RUNS BASICALLY
DOWN US 84 FROM CLOVIS TO SNYDER. ADJUSTMENTS TO POPS WILL BE TO
NUDGE UPWARD TO AROUND 40 PCT ACROSS THE NWRN ZONES WITH 30 PCT
ELSEWHERE. WILL LEAVE THE EVENING POPS AS IS FOR NOW AND
REEVALUATE THIS AFTERNOON. SHOULD ANOTHER GOOD BATCH OF CONVECTION
DEVELOP UPSTREAM WILL LIKELY INCREASE POPS FOR TONIGHT.
PREV DISCUSSION... /ISSUED 628 AM CDT WED AUG 14 2013/
AVIATION...
VFR CONDITIONS ARE HOLDING IN AT KLBB WHILE MVFR CEILINGS HAVE
DEVELOPED AT KCDS. THERE STILL IS A POTENTIAL THAT KLBB COULD DROP
INTO MVFR BY SUNRISE BUT CONFIDENCE WAS NOT HIGH ENOUGH TO ADD TO
THE TAFS AT THIS TIME. SHOULD SEE VFR CONDITIONS BY LATE MORNING
AT BOTH TERMINALS. STILL IS QUITE A BIT OF UNCERTAINTY IF WE WILL
SEE ANOTHER ROUND OF THUNDERSTORMS AT EITHER OF THE TERMINALS LATE
TONIGHT INTO EARLY THURSDAY MORNING BUT CONFIDENCE IS HIGH ENOUGH
TO INCLUDE PROB30 GROUPS AT BOTH SITES. THERE MAY BE SOME CHANGES
IN THE TIMING IN THE TAFS AS WE SEE HOW CONDITIONS CHANGE THROUGH
THE DAY.
JORDAN
PREV DISCUSSION... /ISSUED 438 AM CDT WED AUG 14 2013/
SHORT TERM...
BUSY START TO THIS SET OF MIDNIGHT SHIFTS AS AN ONGOING COMPLEX OF
THUNDERSTORMS OFF THE CAPROCK AND OVER THE ROLLING PLAINS HAS
PRODUCED SOME IMPRESSIVE RAINFALL AMOUNTS. THE HIGHEST THAT WE HAVE
SEEN WAS NEARLY 5 INCH PER HOUR RAINFALL RATES AT THE WEST TEXAS
MESONET STATION IN POST SHORTLY AFTER 315 AM. ALSO SEEING SIMILAR
RAINFALL RATES AT THE GUTHRIE MESONET SITE RIGHT BEFORE 4 AM.
FLOODING REPORTS HAVE BEEN HARD TO COME BY AT THIS TIME OF NIGHT AND
FORTUNATELY THE BULK OF THE STORMS HAVE BEEN ACROSS SPARSELY
POPULATED AREAS. HOWEVER...SOME UNLUCKY CITIES SUCH AS POST HAVE
BEEN ON THE RECEIVING END OF THE RAINFALL. FORECAST-WISE...THE
ONGOING ACTIVITY ALSO POSES A PROBLEM WITH THE FORECAST TODAY.
STORMS HAVE CONTINUED TO TRY AND REDEVELOP ACROSS EASTERN NEW MEXICO
AS A SERIES OF WEAK SHORTWAVES MOVES OVER THE REGION IN
NORTHWESTERLY FLOW ALOFT.
BIGGEST CONCERN FOR ADDITIONAL CONVECTION TODAY AND TONIGHT IS HOW
MUCH MORE STABLE THE ATMOSPHERE WILL BE WITH THE DEPARTING SERIES OF
STORMS. ON THE OTHER HAND...11-3.9 MICRON IMAGERY SHOWS LITTLE IN
THE WAY OF UPSTREAM CLOUD COVER AND DECENT VENTING OF THE CURRENT
CLOUD COVER OUT OF THE REGION SO WE MAY PICK UP SOME DAYTIME HEATING
WHICH COULD LEAD TO DESTABILIZATION LATER IN THE DAY ACROSS THE
AREA. MODELS ARE NOT VERY CONSISTENT WITH THE COVERAGE OR
DEVELOPMENT OF CONVECTION LATER TODAY SO A LOT WILL DEPEND ON HOW
THINGS UNFOLD THIS MORNING. THERE IS TO AN EXTENT SOME AGREEMENT OF
ANOTHER SHORTWAVE MOVING ACROSS THE AREA BUT THE TIMING REMAINS
HIGHLY VARIABLE WITH THE NAM PUSHING THIS ACROSS BY THIS AFTERNOON
WHILE THE GFS/ECMWF ARE LATER IN THE DAY/EARLY IN THE EVENING. DID
TAPER OFF POPS SOME THIS MORNING FOR THE 7AM-1PM TIME FRAME AS
CURRENT ACTIVITY PUSHES OUT OF THE AREA. HOWEVER...UNCERTAINTY ON
HOW THINGS WILL UNFOLD HIS AFTERNOON KEPT POPS IN THE LOW TO
MID-RANGE CHANCE FOR NOW. AMPLE MOISTURE WILL STILL BE ACROSS THE
REGION SO LOCALLY HEAVY RAINFALL COULD BE EXPECTED AGAIN WITH THE
STRONGER OF ANY STORMS THAT DEVELOP. MILD TEMPERATURES CAN BE
EXPECTED TODAY THANKS TO EARLY CLOUD COVER AND THE RAINFALL EARLY
THIS MORNING.
JORDAN
LONG TERM...
ONLY MINOR ADJUSTMENTS MADE TO THE LONG TERM GIVEN THE RATHER BUSY
SHORT TERM. UNSETTLED WEATHER STILL APPEARS IN THE CARDS FOR WEST
TEXAS THROUGH LATE WEEK AS NORTHWESTERLY FLOW ALOFT PREVAILS AND A
FRONTAL BOUNDARY AND RICH MOISTURE /HIGH THETA-E AIR/ LINGERS.
TRICKY PART REMAINS PICKING OUT THE SUBTLE DETAILS INCLUDING THE
TIMING OF ANY SHORTWAVES THAT MAY ENHANCE RAIN CHANCES AND
DETERMINING THE EXACT POSITION OF THE LOW-LEVEL FOCUSES THAT MAY
HELP GUIDE WHERE THE BEST RAIN CHANCES WILL BE DURING ANY PERIOD.
THAT SAID...THERE IS DECENT AGREEMENT THAT A PRONOUNCED SHORTWAVE
TROUGH WILL APPROACH FROM WESTERN KANSAS LATE THURSDAY INTO EARLY
FRIDAY AND THIS MAY PROVIDED AN ENHANCED PERIOD FOR STORM
CHANCES...PERHAPS FAVORING THE EASTERN ZONES. A RENEWED SURGE OF
EASTERLY LOW-LEVEL FLOW MAY FOLLOW WITH THE MOIST UPSLOPE FLOW
JUSTIFYING MAINTAINING AT LEAST LOW POPS FRIDAY AFTERNOON/EVENING.
BY THIS TIME THE UPPER FLOW WILL TURN MERIDIONAL...MAKING IT
DIFFICULT FOR CONVECTION ORIGINATING OVER THE MOUNTAINS OF NM/CO
TO MAKE IT INTO THE SOUTH PLAINS THOUGH. THROUGH THIS LATE WEEK
PERIOD...0-6 KM SHEAR WILL BE DECENT /AROUND 30 KNOTS/ AND IF
SUFFICIENT HEATING/INSTABILITY CAN MATERIALIZE...A FEW OF THE
STORMS COULD BE STRONG OR SEVERE. IN ADDITION...ELEVATED MOISTURE
LEVELS ARGUE FOR A HEAVY RAIN THREAT TOO.
WE SHOULD SEE A DRYING TREND AFTER FRIDAY AS THE UPPER FLOW TURNS
MORE NORTHERLY AND ADVECTS IN DRIER AIR ALOFT...THOUGH THE LOW-LEVEL
THETA-E RIDGE MAY PERSIST NEARBY AND COULD KEEP A FEW SHOWER CHANCES
IN THE PICTURE IF THE ECMWF IS CORRECT. THE FLOW WILL FURTHER VEER
TO NORTHEASTERLY EARLY NEXT WEEK WITH DRY CONDITIONS LIKELY TO
CONTINUE. TEMPERATURES SHOULD REMAIN NEAR OR SLIGHTLY BELOW AVERAGE
THROUGH MUCH OF THE PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 82 61 86 62 87 / 40 40 30 30 20
TULIA 81 62 85 63 85 / 30 40 30 40 20
PLAINVIEW 80 63 87 65 88 / 30 40 30 40 20
LEVELLAND 81 64 88 65 92 / 30 40 30 30 20
LUBBOCK 82 65 88 67 90 / 30 40 30 30 20
DENVER CITY 83 66 89 67 94 / 40 30 30 30 20
BROWNFIELD 83 66 90 66 93 / 40 30 30 30 20
CHILDRESS 85 67 89 68 89 / 30 40 30 40 20
SPUR 83 68 90 68 94 / 30 40 30 40 20
ASPERMONT 84 69 89 71 93 / 40 30 30 30 20
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1113 AM CDT WED AUG 14 2013
.UPDATE...
MINOR UPDATE TO BE ISSUED MAINLY TO CATCH UP TO DIURNAL TRENDS.
LINGERING LIGHT RAIN IN THE SOUTH SHOULD QUICKLY DISSIPATE...BUT A
NARROW BAND OF ISOLATED SHOWERS AND THUNDERSTORMS ALREADY
DEVELOPING ACROSS THE WRN PANHANDLE IN AN AREA OF MOIST UPSLOPE
FLOW. THE HRRR SEEMS TO PICK UP ON THIS TREND THE BEST AND
GENERALLY LEAVES IT AS A DISORGANIZED AREA OF ISOLATED TO
SCATTERED CONVECTION. THIS MODELS FOCUS FOR ORGANIZED CONVECTION
IS AGAIN WITH CONVECTION PROGGED TO DEVELOP ACROSS NERN NM. UPPER
FLOW AGAIN PROGGED TO BE RELATIVELY ROBUST FOR THIS TIME OF
YEAR...ON THE ORDER OF 25-35 KTS AT 500 MB...WITH MODEST BUT MOIST
LOW LEVEL EASTERLY COMPONENT TO THE WINDS. PROGGED LOW LEVEL
THETA-E AXIS LATE THIS AFTN THROUGH THE EVENING RUNS BASICALLY
DOWN US 84 FROM CLOVIS TO SNYDER. ADJUSTMENTS TO POPS WILL BE TO
NUDGE UPWARD TO AROUND 40 PCT ACROSS THE NWRN ZONES WITH 30 PCT
ELSEWHERE. WILL LEAVE THE EVENING POPS AS IS FOR NOW AND
REEVALUATE THIS AFTERNOON. SHOULD ANOTHER GOOD BATCH OF CONVECTION
DEVELOP UPSTREAM WILL LIKELY INCREASE POPS FOR TONIGHT.
&&
.PREV DISCUSSION... /ISSUED 628 AM CDT WED AUG 14 2013/
AVIATION...
VFR CONDITIONS ARE HOLDING IN AT KLBB WHILE MVFR CEILINGS HAVE
DEVELOPED AT KCDS. THERE STILL IS A POTENTIAL THAT KLBB COULD DROP
INTO MVFR BY SUNRISE BUT CONFIDENCE WAS NOT HIGH ENOUGH TO ADD TO
THE TAFS AT THIS TIME. SHOULD SEE VFR CONDITIONS BY LATE MORNING
AT BOTH TERMINALS. STILL IS QUITE A BIT OF UNCERTAINTY IF WE WILL
SEE ANOTHER ROUND OF THUNDERSTORMS AT EITHER OF THE TERMINALS LATE
TONIGHT INTO EARLY THURSDAY MORNING BUT CONFIDENCE IS HIGH ENOUGH
TO INCLUDE PROB30 GROUPS AT BOTH SITES. THERE MAY BE SOME CHANGES
IN THE TIMING IN THE TAFS AS WE SEE HOW CONDITIONS CHANGE THROUGH
THE DAY.
JORDAN
PREV DISCUSSION... /ISSUED 438 AM CDT WED AUG 14 2013/
SHORT TERM...
BUSY START TO THIS SET OF MIDNIGHT SHIFTS AS AN ONGOING COMPLEX OF
THUNDERSTORMS OFF THE CAPROCK AND OVER THE ROLLING PLAINS HAS
PRODUCED SOME IMPRESSIVE RAINFALL AMOUNTS. THE HIGHEST THAT WE HAVE
SEEN WAS NEARLY 5 INCH PER HOUR RAINFALL RATES AT THE WEST TEXAS
MESONET STATION IN POST SHORTLY AFTER 315 AM. ALSO SEEING SIMILAR
RAINFALL RATES AT THE GUTHRIE MESONET SITE RIGHT BEFORE 4 AM.
FLOODING REPORTS HAVE BEEN HARD TO COME BY AT THIS TIME OF NIGHT AND
FORTUNATELY THE BULK OF THE STORMS HAVE BEEN ACROSS SPARSELY
POPULATED AREAS. HOWEVER...SOME UNLUCKY CITIES SUCH AS POST HAVE
BEEN ON THE RECEIVING END OF THE RAINFALL. FORECAST-WISE...THE
ONGOING ACTIVITY ALSO POSES A PROBLEM WITH THE FORECAST TODAY.
STORMS HAVE CONTINUED TO TRY AND REDEVELOP ACROSS EASTERN NEW MEXICO
AS A SERIES OF WEAK SHORTWAVES MOVES OVER THE REGION IN
NORTHWESTERLY FLOW ALOFT.
BIGGEST CONCERN FOR ADDITIONAL CONVECTION TODAY AND TONIGHT IS HOW
MUCH MORE STABLE THE ATMOSPHERE WILL BE WITH THE DEPARTING SERIES OF
STORMS. ON THE OTHER HAND...11-3.9 MICRON IMAGERY SHOWS LITTLE IN
THE WAY OF UPSTREAM CLOUD COVER AND DECENT VENTING OF THE CURRENT
CLOUD COVER OUT OF THE REGION SO WE MAY PICK UP SOME DAYTIME HEATING
WHICH COULD LEAD TO DESTABILIZATION LATER IN THE DAY ACROSS THE
AREA. MODELS ARE NOT VERY CONSISTENT WITH THE COVERAGE OR
DEVELOPMENT OF CONVECTION LATER TODAY SO A LOT WILL DEPEND ON HOW
THINGS UNFOLD THIS MORNING. THERE IS TO AN EXTENT SOME AGREEMENT OF
ANOTHER SHORTWAVE MOVING ACROSS THE AREA BUT THE TIMING REMAINS
HIGHLY VARIABLE WITH THE NAM PUSHING THIS ACROSS BY THIS AFTERNOON
WHILE THE GFS/ECMWF ARE LATER IN THE DAY/EARLY IN THE EVENING. DID
TAPER OFF POPS SOME THIS MORNING FOR THE 7AM-1PM TIME FRAME AS
CURRENT ACTIVITY PUSHES OUT OF THE AREA. HOWEVER...UNCERTAINTY ON
HOW THINGS WILL UNFOLD HIS AFTERNOON KEPT POPS IN THE LOW TO
MID-RANGE CHANCE FOR NOW. AMPLE MOISTURE WILL STILL BE ACROSS THE
REGION SO LOCALLY HEAVY RAINFALL COULD BE EXPECTED AGAIN WITH THE
STRONGER OF ANY STORMS THAT DEVELOP. MILD TEMPERATURES CAN BE
EXPECTED TODAY THANKS TO EARLY CLOUD COVER AND THE RAINFALL EARLY
THIS MORNING.
JORDAN
LONG TERM...
ONLY MINOR ADJUSTMENTS MADE TO THE LONG TERM GIVEN THE RATHER BUSY
SHORT TERM. UNSETTLED WEATHER STILL APPEARS IN THE CARDS FOR WEST
TEXAS THROUGH LATE WEEK AS NORTHWESTERLY FLOW ALOFT PREVAILS AND A
FRONTAL BOUNDARY AND RICH MOISTURE /HIGH THETA-E AIR/ LINGERS.
TRICKY PART REMAINS PICKING OUT THE SUBTLE DETAILS INCLUDING THE
TIMING OF ANY SHORTWAVES THAT MAY ENHANCE RAIN CHANCES AND
DETERMINING THE EXACT POSITION OF THE LOW-LEVEL FOCUSES THAT MAY
HELP GUIDE WHERE THE BEST RAIN CHANCES WILL BE DURING ANY PERIOD.
THAT SAID...THERE IS DECENT AGREEMENT THAT A PRONOUNCED SHORTWAVE
TROUGH WILL APPROACH FROM WESTERN KANSAS LATE THURSDAY INTO EARLY
FRIDAY AND THIS MAY PROVIDED AN ENHANCED PERIOD FOR STORM
CHANCES...PERHAPS FAVORING THE EASTERN ZONES. A RENEWED SURGE OF
EASTERLY LOW-LEVEL FLOW MAY FOLLOW WITH THE MOIST UPSLOPE FLOW
JUSTIFYING MAINTAINING AT LEAST LOW POPS FRIDAY AFTERNOON/EVENING.
BY THIS TIME THE UPPER FLOW WILL TURN MERIDIONAL...MAKING IT
DIFFICULT FOR CONVECTION ORIGINATING OVER THE MOUNTAINS OF NM/CO
TO MAKE IT INTO THE SOUTH PLAINS THOUGH. THROUGH THIS LATE WEEK
PERIOD...0-6 KM SHEAR WILL BE DECENT /AROUND 30 KNOTS/ AND IF
SUFFICIENT HEATING/INSTABILITY CAN MATERIALIZE...A FEW OF THE
STORMS COULD BE STRONG OR SEVERE. IN ADDITION...ELEVATED MOISTURE
LEVELS ARGUE FOR A HEAVY RAIN THREAT TOO.
WE SHOULD SEE A DRYING TREND AFTER FRIDAY AS THE UPPER FLOW TURNS
MORE NORTHERLY AND ADVECTS IN DRIER AIR ALOFT...THOUGH THE LOW-LEVEL
THETA-E RIDGE MAY PERSIST NEARBY AND COULD KEEP A FEW SHOWER CHANCES
IN THE PICTURE IF THE ECMWF IS CORRECT. THE FLOW WILL FURTHER VEER
TO NORTHEASTERLY EARLY NEXT WEEK WITH DRY CONDITIONS LIKELY TO
CONTINUE. TEMPERATURES SHOULD REMAIN NEAR OR SLIGHTLY BELOW AVERAGE
THROUGH MUCH OF THE PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 82 61 86 62 87 / 40 40 30 30 20
TULIA 81 62 85 63 85 / 30 40 30 40 20
PLAINVIEW 80 63 87 65 88 / 30 40 30 40 20
LEVELLAND 81 64 88 65 92 / 30 40 30 30 20
LUBBOCK 82 65 88 67 90 / 30 40 30 30 20
DENVER CITY 83 66 89 67 94 / 40 30 30 30 20
BROWNFIELD 83 66 90 66 93 / 40 30 30 30 20
CHILDRESS 85 67 89 68 89 / 30 40 30 40 20
SPUR 83 68 90 68 94 / 30 40 30 40 20
ASPERMONT 84 69 89 71 93 / 40 30 30 30 20
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
941 AM CDT WED AUG 14 2013
.UPDATE...
THE CONVECTIVE COMPLEX OVER WESTERN COUNTIES CONTINUES TO WEAKEN
WHILE BRINGING STEADY BENEFICIAL RAINS TO AREAS GENERALLY WEST OF
I-35 WEST. A FEW OF THESE SHOWERS HAVE MADE IT AS FAR EAST AS
TARRANT COUNTY LATE THIS MORNING. EAST AND SOUTH OF THE WEAKENING
STORM COMPLEX...TEMPERATURES SHOULD BE ABLE TO CLIMB INTO THE
UPPER 80S...ALLOWING FOR SCATTERED STORMS TO DEVELOP BY THIS
AFTERNOON. COVERAGE SHOULD BE HIGHEST OVER THE SOUTHERN-MOST
COUNTIES WHERE THE BEST MOISTURE AND INSTABILITY RESIDE...WITH
SLIGHTLY LESS OR WIDELY SCATTERED COVERAGE EXPECTED IN DALLAS-
FORT WORTH AND SURROUNDING AREAS. WILL CONTINUE WITH THE HIGHEST
POPS IN THE SOUTH THIS AFTERNOON DECREASING WITH LATITUDE TO NEAR
20 PERCENT ALONG THE RED RIVER. THE SEVERE THREAT WILL BE MARGINAL
AND THE BEST CHANCES FOR SEVERE STORMS CONTAINING DAMAGING WINDS
WILL LIKELY BE SOUTH OF THE INTERSTATE 20 CORRIDOR WHERE MLCAPE
WILL EXCEED 1000J/KG AND SURFACE TEMPS WILL BE WARMEST. THE
FORECAST LOOKS ON TRACK AT THIS TIME...THOUGH ADJUSTMENTS COULD BE
MADE LATER DEPENDING ON FUTURE RADAR TRENDS AND UPDATED MODEL
DATA.
30
&&
.AVIATION...
FOR THE 12Z TAFS...THE PRIMARY AVIATION WEATHER CONCERN IS
THUNDERSTORM CHANCES THROUGH TONIGHT.
SHORT TERM FORECAST...A LINE OF SHOWERS AND THUNDERSTORMS WAS
DRAPED JUST SOUTH OF MOST METROPLEX AREA TAF SITES...HOLDING NORTH
OF WACO AT THE TIME OF THIS DISCUSSION. AFW/DFW/DAL WERE ALL AT
LEAST 10 NM REMOVED FROM THIS LINE OF CONVECTION BY 1130Z...SO
WENT AHEAD WITH JUST A VCSH MENTION THROUGH 13Z FOR THESE SITES.
FTW/GKY WERE WITHIN 10 MILES OF ONGOING CONVECTION...SO CONTINUED
TO CARRY VCTS FOR THESE SITES THROUGH 13 OR 14Z.
FOR KACT...AS OF 1130Z ALL ONGOING CONVECTION WAS WELL NORTH OF
WACO...BUT REGIONAL RADARS SHOWED AN OUTFLOW BOUNDARY MOVING
RAPIDLY TO THE SOUTH JUST EAST OF I-35. WENT AHEAD AND CARRIED A
VCSH FOR KACT THIS MORNING DUE TO UNCERTAINTY ON NEW PRECIPITATION
DEVELOPING ALONG THIS SOUTHWARD MOVING OUTFLOW.
THROUGH THIS AFTERNOON... PERSISTENT CONVECTION ACROSS WEST TEXAS
OVERNIGHT AND EARLY THIS MORNING HAS ACTUALLY CAUSED AN UPPER
LEVEL DISTURBANCE TO DEVELOP. THIS DISTURBANCE IS EXPECTED TO MOVE
SLOWLY SOUTHEAST TOWARDS NORTH TX FOR THIS AFTERNOON. WHETHER THIS
WILL CAUSE SHOWERS AND THUNDERSTORMS TO DEVELOP AROUND THE DFW
AREA THIS AFTERNOON IS THE MAJOR FORECAST CONCERN FOR TODAY.
THUNDERSTORM CHANCES SEEM DEPENDENT UPON THE DFW AREA GETTING SOME
BREAKS IN THE CLOUD COVER BEFORE THE UPPER DISTURBANCE ARRIVES
BY/AROUND 21Z. WITHOUT MUCH CONFIDENCE IN CLOUDS CLEARING UP BY
THAT TIME ONLY CARRIED VCSH FOR ALL METROPLEX AREA TAFS THROUGH
01Z. WILL HAVE TO MONITOR CLOUD COVER AND THE UPSTREAM DISTURBANCE
THROUGH THE MORNING HRS AND ADJUST THE TAFS ACCORDINGLY.
FOR KACT...MORE OR LESS FOLLOWED OUTPUT FROM THE HRRR WHICH BREAKS
OUT SCATTERED THUNDERSTORM ACTIVITY ALL AROUND WACO AFTER 18Z NEAR
A STALLED OUT FRONTAL BOUNDARY IN THE AREA. WITH THE FRONT ALREADY
IN PLACE...CONFIDENCE WAS HIGH ENOUGH TO BELIEVE THE HRRR OUTPUT
AND PLACE 3 HRS OF -TSRA IN THE TAF FROM 18Z TO 21Z. AFTER 21Z
CARRIED VCSH WITHOUT MUCH CONFIDENCE ON WHAT THE INFLUENCE OF THE
UPPER LEVEL DISTURBANCE WILL BE ON THE WACO AREA.
CAVANAUGH
&&
.PREV DISCUSSION... /ISSUED 416 AM CDT WED AUG 14 2013/
SURFACE ANALYSIS EARLY THIS MORNING SHOWED TWO SURFACE BOUNDARIES
THAT WILL HAVE AN EFFECT ON PRECIPITATION COVERAGE AND TEMPS
ACROSS NORTH TEXAS TODAY AND TONIGHT. CONSOLIDATED OUTFLOW
BOUNDARY AND EFFECTIVE COLD FRONT WAS ACROSS THE SOUTHERN PART OF
THE CWA AND WAS STATIONARY ALONG A LINE FROM NEAR LAMPASAS TO
CENTERVILLE. THE SECOND BOUNDARY WAS LOCATED ALONG THE LEADING
EDGE OF SOME LOWER THETA-E AIR AND MAY BE CORRELATED WITH A FRONTAL
BOUNDARY AT 850 MB. THIS BOUNDARY WAS ANALYZED FROM NEAR BOWIE TO
SOUTH OF PARIS AND WAS MOVING SOUTH.
WILL CONTINUE WITH CHANCE POPS ACROSS NORTH AND CENTRAL TEXAS
TODAY...WITH HIGHEST POPS AND GREATEST COVERAGE OF STORMS FORECAST
IN SOUTHERN AREAS THIS AFTERNOON. THE CLUSTER OF ELEVATED STORMS
THIS MORNING ACROSS TARRANT AND PARKER COUNTIES MAY CONTINUE TO
EXPAND AS IT DEVELOPS TO THE EAST AND SOUTHEAST.
BY THIS AFTERNOON...EXPECT THE MORNING ACTIVITY TO DISSIPATE AS
THE NORTHERN SURFACE BOUNDARY MOVES SOUTH. BY MID AFTERNOON...THIS
BOUNDARY WILL MOVE TO NEAR A TYLER TO WACO LINE AND BE A FOCUS FOR
SCATTERED STRONG /ISOLATED SEVERE/ THUNDERSTORMS. DESPITE WEAK
DEEP LAYER SHEAR...EXPECT POCKETS OF INSTABILITY UP TO 2000 J/KG
TO SUPPORT STRONG STORMS CAPABLE OF MARGINALLY SEVERE HAIL AND
WIND GUSTS. THE AFTERNOON ACTIVITY WILL PERSIST INTO THE EVENING
HOURS...BUT WILL TEND TO DIMINISH QUICKLY AFTER MIDNIGHT AS IT
SHIFTS TO THE SOUTH AND SOUTHEAST WITH THE SURFACE BOUNDARY.
RAIN CHANCES WILL BE CONFINED TO WESTERN AND SOUTHERN ZONES ON
THURSDAY AS DRIER AND MORE STABLE AIR WORKS INTO THE AREA FROM THE
EAST AND NORTHEAST. THURSDAY NIGHT SHOULD BE DRY...BUT A RATHER
STRONG SHORTWAVE TROUGH IS FORECAST TO DIG SOUTHEAST INTO OKLAHOMA
BY FRIDAY MORNING. EVEN THOUGH DEEP-LAYER MOISTURE WILL NOT BE AS
FAVORABLE AS TODAY FOR CONVECTION...THE FORCING FOR LARGE SCALE
ASCENT ACROSS NORTH TEXAS LOOKS STRONG BY AUGUST STANDARDS. HAVE
THEREFORE INTRODUCED CHANCE POPS FOR MOST OF THE AREA DURING THE
DAY FRIDAY.
DRY WEATHER FORECAST FROM FRIDAY NIGHT...THROUGH THE WEEKEND...AND
INTO EARLY NEXT WEEK AS THE ROCKIES UPPER HIGH EXPANDS AND THE
UPPER FLOW FLATTENS ACROSS THE CONUS. HIGH TEMPERATURES WILL
RETURN TO NEAR SEASONAL NORMALS IN THE MID-UPPER 90S BY SATURDAY...
BUT NO 100 DEGREE HEAT IS IN THE FORECAST THROUGH DAY 7 /TUES AUG
20/.
...09...
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 92 72 92 70 91 / 30 20 10 10 20
WACO, TX 96 74 92 68 94 / 50 40 30 10 20
PARIS, TX 87 63 86 63 87 / 20 10 5 10 30
DENTON, TX 91 70 90 67 89 / 30 10 10 10 30
MCKINNEY, TX 91 67 90 64 90 / 30 10 10 10 30
DALLAS, TX 93 73 92 70 91 / 30 20 10 10 30
TERRELL, TX 91 69 91 65 91 / 30 20 10 10 30
CORSICANA, TX 95 72 92 67 93 / 60 30 10 10 30
TEMPLE, TX 97 73 93 69 94 / 50 40 30 10 20
MINERAL WELLS, TX 91 71 92 68 91 / 40 30 30 10 30
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
92/30
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
656 AM CDT WED AUG 14 2013
.AVIATION...
FOR THE 12Z TAFS...THE PRIMARY AVIATION WEATHER CONCERN IS
THUNDERSTORM CHANCES THROUGH TONIGHT.
SHORT TERM FORECAST...A LINE OF SHOWERS AND THUNDERSTORMS WAS
DRAPED JUST SOUTH OF MOST METROPLEX AREA TAF SITES...HOLDING NORTH
OF WACO AT THE TIME OF THIS DISCUSSION. AFW/DFW/DAL WERE ALL AT
LEAST 10 NM REMOVED FROM THIS LINE OF CONVECTION BY 1130Z...SO
WENT AHEAD WITH JUST A VCSH MENTION THROUGH 13Z FOR THESE SITES.
FTW/GKY WERE WITHIN 10 MILES OF ONGOING CONVECTION...SO CONTINUED
TO CARRY VCTS FOR THESE SITES THROUGH 13 OR 14Z.
FOR KACT...AS OF 1130Z ALL ONGOING CONVECTION WAS WELL NORTH OF
WACO...BUT REGIONAL RADARS SHOWED AN OUTFLOW BOUNDARY MOVING
RAPIDLY TO THE SOUTH JUST EAST OF I-35. WENT AHEAD AND CARRIED A
VCSH FOR KACT THIS MORNING DUE TO UNCERTAINTY ON NEW PRECIPITATION
DEVELOPING ALONG THIS SOUTHWARD MOVING OUTFLOW.
THROUGH THIS AFTERNOON... PERSISTENT CONVECTION ACROSS WEST TEXAS
OVERNIGHT AND EARLY THIS MORNING HAS ACTUALLY CAUSED AN UPPER
LEVEL DISTURBANCE TO DEVELOP. THIS DISTURBANCE IS EXPECTED TO MOVE
SLOWLY SOUTHEAST TOWARDS NORTH TX FOR THIS AFTERNOON. WHETHER THIS
WILL CAUSE SHOWERS AND THUNDERSTORMS TO DEVELOP AROUND THE DFW
AREA THIS AFTERNOON IS THE MAJOR FORECAST CONCERN FOR TODAY.
THUNDERSTORM CHANCES SEEM DEPENDENT UPON THE DFW AREA GETTING SOME
BREAKS IN THE CLOUD COVER BEFORE THE UPPER DISTURBANCE ARRIVES
BY/AROUND 21Z. WITHOUT MUCH CONFIDENCE IN CLOUDS CLEARING UP BY
THAT TIME ONLY CARRIED VCSH FOR ALL METROPLEX AREA TAFS THROUGH
01Z. WILL HAVE TO MONITOR CLOUD COVER AND THE UPSTREAM DISTURBANCE
THROUGH THE MORNING HRS AND ADJUST THE TAFS ACCORDINGLY.
FOR KACT...MORE OR LESS FOLLOWED OUTPUT FROM THE HRRR WHICH BREAKS
OUT SCATTERED THUNDERSTORM ACTIVITY ALL AROUND WACO AFTER 18Z NEAR
A STALLED OUT FRONTAL BOUNDARY IN THE AREA. WITH THE FRONT ALREADY
IN PLACE...CONFIDENCE WAS HIGH ENOUGH TO BELIEVE THE HRRR OUTPUT
AND PLACE 3 HRS OF -TSRA IN THE TAF FROM 18Z TO 21Z. AFTER 21Z
CARRIED VCSH WITHOUT MUCH CONFIDENCE ON WHAT THE INFLUENCE OF THE
UPPER LEVEL DISTURBANCE WILL BE ON THE WACO AREA.
CAVANAUGH
&&
.PREV DISCUSSION... /ISSUED 416 AM CDT WED AUG 14 2013/
SURFACE ANALYSIS EARLY THIS MORNING SHOWED TWO SURFACE BOUNDARIES
THAT WILL HAVE AN EFFECT ON PRECIPITATION COVERAGE AND TEMPS
ACROSS NORTH TEXAS TODAY AND TONIGHT. CONSOLIDATED OUTFLOW
BOUNDARY AND EFFECTIVE COLD FRONT WAS ACROSS THE SOUTHERN PART OF
THE CWA AND WAS STATIONARY ALONG A LINE FROM NEAR LAMPASAS TO
CENTERVILLE. THE SECOND BOUNDARY WAS LOCATED ALONG THE LEADING
EDGE OF SOME LOWER THETA-E AIR AND MAY BE CORRELATED WITH A FRONTAL
BOUNDARY AT 850 MB. THIS BOUNDARY WAS ANALYZED FROM NEAR BOWIE TO
SOUTH OF PARIS AND WAS MOVING SOUTH.
WILL CONTINUE WITH CHANCE POPS ACROSS NORTH AND CENTRAL TEXAS
TODAY...WITH HIGHEST POPS AND GREATEST COVERAGE OF STORMS FORECAST
IN SOUTHERN AREAS THIS AFTERNOON. THE CLUSTER OF ELEVATED STORMS
THIS MORNING ACROSS TARRANT AND PARKER COUNTIES MAY CONTINUE TO
EXPAND AS IT DEVELOPS TO THE EAST AND SOUTHEAST.
BY THIS AFTERNOON...EXPECT THE MORNING ACTIVITY TO DISSIPATE AS
THE NORTHERN SURFACE BOUNDARY MOVES SOUTH. BY MID AFTERNOON...THIS
BOUNDARY WILL MOVE TO NEAR A TYLER TO WACO LINE AND BE A FOCUS FOR
SCATTERED STRONG /ISOLATED SEVERE/ THUNDERSTORMS. DESPITE WEAK
DEEP LAYER SHEAR...EXPECT POCKETS OF INSTABILITY UP TO 2000 J/KG
TO SUPPORT STRONG STORMS CAPABLE OF MARGINALLY SEVERE HAIL AND
WIND GUSTS. THE AFTERNOON ACTIVITY WILL PERSIST INTO THE EVENING
HOURS...BUT WILL TEND TO DIMINISH QUICKLY AFTER MIDNIGHT AS IT
SHIFTS TO THE SOUTH AND SOUTHEAST WITH THE SURFACE BOUNDARY.
RAIN CHANCES WILL BE CONFINED TO WESTERN AND SOUTHERN ZONES ON
THURSDAY AS DRIER AND MORE STABLE AIR WORKS INTO THE AREA FROM THE
EAST AND NORTHEAST. THURSDAY NIGHT SHOULD BE DRY...BUT A RATHER
STRONG SHORTWAVE TROUGH IS FORECAST TO DIG SOUTHEAST INTO OKLAHOMA
BY FRIDAY MORNING. EVEN THOUGH DEEP-LAYER MOISTURE WILL NOT BE AS
FAVORABLE AS TODAY FOR CONVECTION...THE FORCING FOR LARGE SCALE
ASCENT ACROSS NORTH TEXAS LOOKS STRONG BY AUGUST STANDARDS. HAVE
THEREFORE INTRODUCED CHANCE POPS FOR MOST OF THE AREA DURING THE
DAY FRIDAY.
DRY WEATHER FORECAST FROM FRIDAY NIGHT...THROUGH THE WEEKEND...AND
INTO EARLY NEXT WEEK AS THE ROCKIES UPPER HIGH EXPANDS AND THE
UPPER FLOW FLATTENS ACROSS THE CONUS. HIGH TEMPERATURES WILL
RETURN TO NEAR SEASONAL NORMALS IN THE MID-UPPER 90S BY SATURDAY...
BUT NO 100 DEGREE HEAT IS IN THE FORECAST THROUGH DAY 7 /TUES AUG
20/.
...09...
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 92 72 92 70 91 / 30 20 10 10 20
WACO, TX 96 74 92 68 94 / 50 40 30 10 20
PARIS, TX 87 63 86 63 87 / 20 10 5 10 30
DENTON, TX 91 70 90 67 89 / 30 10 10 10 30
MCKINNEY, TX 91 67 90 64 90 / 30 10 10 10 30
DALLAS, TX 93 73 92 70 91 / 30 20 10 10 30
TERRELL, TX 91 69 91 65 91 / 30 20 10 10 30
CORSICANA, TX 95 72 92 67 93 / 50 30 10 10 30
TEMPLE, TX 97 73 93 69 94 / 50 40 30 10 20
MINERAL WELLS, TX 91 71 92 68 91 / 40 30 30 10 30
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1157 PM CDT TUE AUG 13 2013
.AVIATION...
SECOND WAVE OF STORMS NEARING THE DKR REGION HAVE BEGUN TO WEAKEN
QUICKLY AND ANOTHER CLUSTER DEVELOPING AGAIN TO THE NORTHWEST OF
DKR. MODEL SOUNDINGS AND ACARS SHOW THE WARM SOUNDINGS (CAPPED)
DOWN ACROSS THE AREA TERMINALS OVERNIGHT - THOUGH THIS THIRD WAVE
MAY MAKE A BIT MORE PROGRESS AND COULD BRING A WINDSHIFT TO UTS
BETWEEN 07-10Z. OTHERWISE PREVIOUS PACKAGE STILL LOOKS CLOSE BUT
TRENDING A LITTLE LATER WITH THE RAINFALL AND CONFIDENCE HAS GROWN
THAT LATE AFTERNOON AND EARLY EVENING WILL PROBABLY BE THE BEST
WINDOW FOR SHRA/TSRA AT IAH/HOU TERMINALS. WINDS SHOULD SWING TO
THE NW LATE MORNING AND EARLY AFTERNOON (OUTFLOW) THEN NORTHEAST
IN THE AFTERNOON AS BROAD DIFFUSE FRONTAL BOUNDARY SAGS SOUTH.
DECREASING COVERAGE THROUGH THE EVENING HOURS AND MAY BE JUST SHRA
AFTER 02Z/15. LINGERING LL MOISTURE WILL ALSO PROBABLY LEAD TO
SOME PATCHY MVFR CIGS AFTER 06Z/15. 45
&&
.PREV DISCUSSION... /ISSUED 941 PM CDT TUE AUG 13 2013/
UPDATE...
SEE DISCUSSION FOR EVENING UPDATE.
DISCUSSION...
SHOWERS AND THUNDERSTORMS ACROSS THE CWA BORDER HAVE HAD TROUBLE
MOVING SOUTHWARDS THIS EVENING. THIS ACTIVITY IS IN RESPONSE TO A
WEAK FRONTAL BOUNDARY THAT IS SAGGING SOUTHWARDS. RAIN LOOKS TO
START IN THE NORTHEASTERN COUNTIES EARLY THIS MORNING THEN SLOWLY
SPREAD TOWARDS THE SOUTH WITH THE BOUNDARY DURING THE DAY. THE
CHANCE OF RAIN OVERNIGHT DOES LOOK TO BE IN QUESTION AS DRY MID-
LEVEL AIR REMAINS IN PLACE (ESPECIALLY FURTHER TOWARDS THE
SOUTH). THIS CAN BE SEEN IN THE 0Z SOUNDING FROM KCRP THAT REVEALS
A PWAT OF ONLY 1.50". THE KFWD SOUNDING ON THE OTHER HAND HAS A
PWAT VALUE OF OVER 2.00". MODELS ARE FORECASTING FOR THE DRY AIR
TO BE PUSHED SOUTHWARDS TOMORROW BUT THE EXACT TIMING OF THIS WILL
BE TOUGH TO PREDICT. LIFT TOMORROW WILL COME FROM THE DIFFUSE
BOUNDARY WHICH SHOULD MAKE IT TO JUST NORTH OF INTERSTATE 10.
CONVECTIVE OUTFLOWS WILL THEN PUSH SOUTHWARDS LATER IN THE DAY
AIDING SHOWER AND THUNDERSTORM DEVELOPMENT. THERE SHOULD BE
ENOUGH DAYTIME HEATING TO ALLOW FOR CONVECTIVE TEMPERATURES TO BE
REACHED. THE SOUTHWESTERN ZONES WILL BE THE LAST TO SEE THE RAIN
AND COVERAGE SHOULD BE LESS DUE TO THE LOWER MOISTURE AND WEAKER
LAPSE RATES. UPPER LEVEL SUPPORT ALSO APPEARS TO BE MORE OFF
TOWARDS THE EAST TOMORROW. GIVEN THESE TRENDS HAVE PULLED POPS
BACK SLIGHTLY. NEW ZONES WILL BE OUT SHORTLY. 23
PREV DISCUSSION... /ISSUED 814 PM CDT TUE AUG 13 2013/
AVIATION...
STORMS ALONG AND SOUTH OF A VERY DIFFUSE FRONTAL BOUNDARY HAVE
BEEN WANING QUICKLY. SOME HIGH CLOUDS WILL DRIFT SOUTHEAST INTO
THE AREA OVERNIGHT. VFR CONDITIONS SHOULD PREVAIL OVERNIGHT WITH
SOME SHOWERS AND POSSIBLY A THUNDERSTORM NORTHEAST OF THE UTS
TERMINAL. TOMORROW IS NOT SO STRAIGHT FORWARD...THE DIFFUSE FRONT
CONTINUES TO SAG SOUTHWARD AS UPPER LEVEL RIDGING (CAPPING) OVER
CENTRAL AND SOUTHERN TX SLIDES SLOWLY WEST AND TROUGHING DIPS
DOWN INTO LA. RICH MOISTURE AND COOLING TEMPERATURES ALOFT IN
COMBINATION WITH A LL FOCUS POINTS TOWARDS THE DEVELOPMENT OF
SHRA/TSRA BUT MODELS ARE IN DISAGREEMENT WITH RESPECT TO TIMING
AND LOCATION BETWEEN 12Z AND 03Z/14 AND IN SOME CASES WIDELY. NOT
THAT CONFIDENT CONVECTION WILL BE WIDESPREAD IN THE NORTH IN THE
MORNING BUT AS HEATING INCREASES EXPECT THAT AT LEAST SCATTERED
SHRA/TSRA SHOULD DEVELOP. EVENTUALLY OUTFLOW SPREADS SOUTH AND
SHOULD REACH THE METRO TERMINALS MID TO LATE AFTERNOON SO PEAK IN
ACTIVITY WILL PROBABLY BE IN THE AFTERNOON FOR THE HOUSTON AREA
TERMINALS. STORMS SHOULD WANE AGAIN TOMORROW EVENING ESPECIALLY IN
THE SOUTHWEST WHERE STRONGER CAP WILL STILL BE IN PLACE. 45
PREV DISCUSSION... /ISSUED 346 PM CDT TUE AUG 13 2013/
DISCUSSION...
MUCH CONVECTIVE ACTIVITY OCCURRING ALONG A NORTHERN TEXAS (QUASI)
STATIONARY BOUNDARY THAT MAY EVENTUAL IMPACT OUR NORTH(EAST)ERN
COUNTIES WITHIN THE NEXT 4 TO 6 HOURS. A VERY HEATED AND MOIST
DOWNSTREAM AIR MASS FOR THIS STATIONARY BOUNDARY...OR SUBSEQUENT
CONVECTIVE OUTFLOW...TO WORK WITH IN THE COMING 24-36 HOURS.
THERE IS STILL SUBSIDENCE TO WORK WITH AS THERE HAVE BEEN RECENT
HEIGHT RISES AND A FEW DEGREES OF WARMTH AT THE 85-7H LEVELS...BUT
THE UPPER LEVELS REMAIN FAIRLY DIFFLUENT AS EAST TEXAS FALLS
WITHIN A (RELATIVELY) MILD MID-UPPER LEVEL HEIGHT WEAKNESS BETWEEN
DESERT SOUTHWEST AND FLORIDA-CENTERED RIDGING.
ALL OF THE THERMODYNAMIC INDICES ARE THERE TO SUPPORT RETURNING
SCATTERED SHOWERS AND STORMS BEGINNING AS EARLY AS MID-WEDNESDAY
MORNING. K-INDICES AROUND 40...L.I. IN THE -5 REALM...AND ABOVE
1 K J/KG CAPES FROM THE GFS/NAM PROGS OVER THE NORTHERN CWA
INCREASE THE SHOWER/STORM PROBABILITY. YES...THERE WILL BE SOME
SUBSIDENCE TO DEAL WITH...BUT WITH A CONSISTENT RUN-TO-RUN THEME
OF INTRODUCING WEAK LOWER MS VALLEY TROUGHING (AND WITNESSING WHAT
IS ONGOING ACROSS DFW`S FA)...HAD TO BITE ON THE LIKELY SIDE OF
POPS. GREATER THAN 2 INCH PWATS WILL POOL ALONG `A` BOUNDARY...WHETHER
THAT BE MORE OF A SYNOPTIC OR A SERIES OF MESOSCALE (UPSTREAM
OUTFLOW) BOUNDARIES. OTHER THAN SUBSIDENCE AS A RAIN INHIBITER...THE
ONLY OTHER NEGATIVE TO MORE WIDESPREAD COVERAGE WOULD BE THAT THE
REGION DOES FALL INTO MORE OF A RR QUAD OF THE JET (ALTHOUGH 25-3H
FLOW REMAINS DIFFLUENT).
NEEDLESS TO SAY...BUT WHAT EVOLVES TOMORROW WILL DRIVE THURSDAY`S
FORECAST. SINCE THE FORECAST IS MORE WET TOMORROW...ANTICIPATING
THAT THERE WILL BE SOME RESIDUAL BOUNDARIES LEFT OVER IN THE MIX.
A LESS-WORKED OVER SOUTHERN CWA AIR MASS...WITH POSSIBLE LEFT-OVER
WEDNESDAY SMALL SCALE BOUNDARIES (AND MAYBE SOME ASSISTANCE FROM
THE LOCAL BREEZE?) WILL KEEP CHANCE POPS IN PLAY CLOSER TO THE
COAST THURSDAY INTO FRIDAY. A MUCH DRIER AIR MASS FILTERING IN
ALONG THE WESTERN LEG OF A EASTERN-BASED MID-UPPER TROUGH AXIS
WILL COME OVER US DURING THE WEEKEND...SUBSTANTIALLY LOWERING
RAIN CHANCES.
THE EXTENDED SHOWS NOT MUCH IN THE WAY OF ANY DISCERNIBLE WEATHER
FEATURE THAT WILL INCREASE RAIN CHANCES BEYOND THE LOCAL SCALE
BREEZES. IF ANYTHING...RIDGING TAKES MORE OF A GRIP AND MID-LEVELS
ARE MODELED TO WARM BACK UP INTO THE LOWER 20S BY THIS TIME NEXT
WEEK. AS HAS BEEN THE CASE THESE PAST FEW DAYS...THE BAY OF CAMPECHE
HAS REMAINED SOMEWHAT ACTIVE...WITH THE NWP SUITE MAINTAINING
LOWERING PRESSURES AND A GREATER THAN 2 INCH PW AIR MASS. CENTRAL
GULF SHEAR REMAINS STOUT (30 KTS BETWEEN THE TWO UPPER RIDGES) SO
NOT TOO WORRIED WITH ANY CLOSED-OFF CIRCULATION MOVING TOO FAR
NORTH OF THE BAY. 31
MARINE...
A RELATIVELY FLAT PRESSURE GRADIENT ACROSS THE COASTAL WATERS WILL
KEEP MAINLY LIGHT ONSHORE WINDS AND LOW SEAS IN PLACE THROUGH THE
MIDDLE OF THE WEEK. A WEAK FRONT IS STILL EXPECTED TO APPROACH THE
COAST FROM THE NORTH AND NORTHEAST ON WEDNESDAY NIGHT AND THURSDAY.
THIS BOUNDARY COULD BRING THE AREA A BRIEF PERIOD OF OFFSHORE WINDS.
A WEAK TROUGH OF LOW PRESSURE OVER THE CENTRAL GULF WILL MAINTAIN E-NE
WINDS THROUGH SUNDAY. 43
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 102 76 95 73 95 / 10 20 40 20 20
HOUSTON (IAH) 99 78 96 76 93 / 10 20 30 30 40
GALVESTON (GLS) 94 83 91 81 90 / 10 10 20 40 30
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...23
AVIATION/MARINE...45
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
333 PM CDT WED AUG 14 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 333 PM CDT WED AUG 14 2013
AT 3 PM...THE SATELLITE LOOP SHOWED A BROKEN DECK OF 7 TO 8K FOOT
CLOUDS ACROSS THE FORECAST AREA. THE RAP SEEMS TO HAVE THE BEST
HANDLE ON THESE CLOUDS AND THEY SHOW THAT THESE CLOUDS WILL
GRADUALLY DISSIPATE THIS EVENING.
FOR LATE TONIGHT AND THURSDAY MORNING...THE BUFKIT SOUNDINGS SHOW
THAT THERE WILL BE A DEEP LAYER /UP TO 775 MB/ OF LIGHT WINDS
ACROSS THE AREA. WHILE THIS WOULD BE FAVORABLE FOR THE DEVELOPMENT
OF VALLEY FOG. THE NAM/WRF...GFS...AND RAP CONTINUE TO SHOW THAT
THE TEMPERATURE/DEW POINT SPREAD WILL REMAIN AT OR ABOVE 1C. IN
ADDITION...THE GFS AND NAM/WRF SUGGEST THAT THERE COULD BE STILL
SOME CLOUDS AROUND THE REGION. AS A RESULT...WENT WITH PATCHY
VALLEY FOG FOR THE MISSISSIPPI RIVER AND ITS TRIBUTARIES...AND
AREAS OF FOG IN THE WISCONSIN RIVER VALLEY.
ON THURSDAY...THE MODELS CONTINUE TO SHOW THAT A SHORT WAVE TROUGH
WILL MOVE SOUTHEAST ACROSS SOUTHERN AND WESTERN IOWA. WEAK 925 AND
850 MB MOISTURE TRANSPORT NORTHEAST OF THIS SYSTEM WILL AID IN THE
DEVELOPMENT OF ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS
ACROSS NORTHEAST IOWA...SOUTHEAST MINNESOTA...AND SOUTHWEST
WISCONSIN. WITH ML CAPES LESS THAN 400 J/KG AND VERY WEAK 0-3 KM
AND 0-6 KM...NONE OF THESE THUNDERSTORMS ARE EXPECTED TO BECOME
SEVERE.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 333 PM CDT WED AUG 14 2013
ON FRIDAY...THE 925 MB AND 850 MB WEAK MOISTURE TRANSPORT AND 700
TO 600 MB FRONTOGENESIS REMAINS SOUTHWEST OF THE FORECAST AREA.
IN ADDITION...THERE IS VERY LITTLE SURFACE MOISTURE CONVERGENCE
ACROSS THE AREA. WITH THE MESO MODELS IN AGREEMENT WITH THE GEM
AND ECMWF THAT THE AREA WILL REMAIN DRY...REMOVED THE
PRECIPITATION CHANCES FOR THIS TIME PERIOD.
ON BOTH THURSDAY AND FRIDAY NIGHTS...BOTH THE GFS AND NAM/WRF
SOUNDINGS SHOW A DEEP LAYER /UP TO AT LEAST 800 MB/ OF LIGHT
WINDS. THIS WOULD BE VERY FAVORABLE FOR THE DEVELOPMENT OF VALLEY
FOG. HOWEVER THEY ALSO HINT THAT THERE MAY BE SOME CLOUDS AROUND
THE REGION. ANOTHER FACTOR THAT MAY BE A LIMITING FACTOR IS THE
AMOUNT OF MOISTURE IN THE BOUNDARY LAYER. THE NAM/WRF HAS MUCH
MORE MOISTURE THAN THE GFS. DUE TO THIS UNCERTAINTY...JUST
INTRODUCED PATCHY TO AREAS OF VALLEY FOG ON BOTH NIGHTS.
FROM MONDAY THROUGH WEDNESDAY...THE MODELS ARE CONTINUING TO
STRUGGLE WITH THE 500 MB UPPER AIR PATTERN. THE GFS AND GEM ARE
SHOWING THAT THE UPPER LEVEL RIDGE REMAINS LONGER TO THE WEST THAN
THE ECMWF. AS A RESULT...THE GFS AND GEM ARE FASTER AT MOVING THE
COLD FRONT SOUTHEAST INTO THE FORECAST AREA. MEANWHILE THE ECMWF
HAS THE FRONT REMAINING WELL NORTHWEST OF THE FORECAST AREA. SINCE
THE MODELS HAVE BEEN TRENDING SLOWER DURING THIS TIME PERIOD...THE
CONSENSUS OF OUR OFFICE AND THE SURROUNDING WFOS TO KEEP MOST OF
THE FORECAST AREA DRY DURING THIS TIME FRAME.
&&
.AVIATION...THROUGH 18Z THURSDAY
1227 PM CDT WED AUG 14 2013
HIGH PRESSURE CENTERED OVER EASTERN IOWA AND SOUTHERN WISCONSIN WILL
CONTINUE TO PROVIDE VFR CONDITIONS AT BOTH TAF SITES THROUGH MUCH OF
THE TAF PERIOD. LATEST VISIBLE SATELLITE SHOWS DAYTIME ALTO-CUMULUS
DEVELOPING OVER EASTERN MINNESOTA AND WESTERN WISCONSIN. LATEST
METARS INDICATE CEILING HEIGHTS AT OR ABOVE 7000 FEET OVER THIS
AREA. LATEST DETERMINISTIC MODELS SUGGEST THE POSSIBILITY OF SOME
CLOUDS OVER THE AREA TONIGHT. THIS WILL HAVE AN IMPACT ON ANY
RIVER VALLEY FOG FORMING AND AFFECTING THE TAF SITE LSE. AT THIS
TIME...WILL LEAVE ANY MENTION OF FOG REDUCING VISIBILITY AT LSE
DUE TO SOME CLOUDS INHIBITING FOG FORMATION.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...DTJ
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
315 AM MDT FRI AUG 16 2013
.SHORT TERM...SOME STRATUS AND FOG HAS DEVELOPED EARLY THIS
MORNING OVER THE FAR NERN PLAINS AND MAY EVENTUALLY SPREAD FURTHER
WEST INTO MORGAN AND PARTS OF WELD COUNTY BY 12Z. NEITHER THE RAP
OR HRRR SHOW THIS STRATUS/FOG MOVING INTO THE URBAN CORRIDOR AT
THIS POINT SO WILL KEEP IT EAST OF THE FRONT RANGE.
OTHERWISE AN UPPER RIDGE WILL BUILD OVER WRN COLORADO WITH MAINLY
DRY NNW FLOW ALOFT ACROSS THE AREA. HOWEVER THERE STILL COULD BE
SOME ISOLD HIGHER BASED STORMS OVER THE HIGHER FOOTHILLS...MTNS
AND OVER THE PALMER DIVIDE FM MID AFTN THRU THE EARLY EVENING
HOURS. HIGHS THIS AFTN WILL BE A FEW DEGREES WARMER THAN FRIDAY IN
MOST LOCATIONS AS 850-700 MB TEMPS RISE A COUPLE OF DEGREES.
.LONG TERM...STRONG...HIGH AMPLITUDE UPPER RIDGE OVER THE DESERT
SOUTHWEST/EASTERN GREAT BASIN/ROCKY MOUNTAIN/WESTERN GREAT PLAINS
REGIONS DOES NOT APPEAR TO BE GOING ANYWHERE TOO SOON ACCORDING TO
THE DETERMINISTIC MODELS AND THEIR ENSEMBLE MEMBERS. THE 500 MB
RIDGE APPEARS TO MEANDER BACK AND FORTH/EAST-WEST/ DURING THE
PERIOD...WHICH CAUSES SUBTLE DAY-TO-DAY SHIFTS IN THE AXIS OF
MONSOONAL MOISTURE PLUME CONNECTED TO THE LOWER DESERTS OF ARIZONA
AND NEW MEXICO. MODELS DIFFER SOME WITH ITS POSITION AND ITS
STRENGTH...BUT OVERALL...THIS CONVEYOR BELT OF SUBTROPICAL
MOISTURE APPEARS TO REMAIN LARGELY ALONG AND WEST OF THE
CONTINENTAL DIVIDE THROUGH THE MIDDLE OF NEXT WEEK. RAIN/T-STORM
CHANCES WILL BE AT THEIR LOWEST THIS WEEKEND FOR NORTH CENTRAL
AND NORTHEAST COLORADO...WITH TEMPERATURES LIKELY TO BE THEIR
WARMEST. NOT SURE WE/LL SEE THE NEAR RECORD HIGH TEMPS ADVERTISED
BY THE GFS...PROBABLY MORE LIKE THOSE OFFERED BY THE ECMWF...BUT
STILL 1-3C ABOVE THE AVERAGE FOR THE DATE. NEXT WEEK...MODELS
INDICATE SLIGHT COOLING...WITH TEMPERATURES RETURNING TO NEAR
AVERAGE...ALONG WITH A SLIGHTLY BETTER CHANCE OF THE AFTERNOON/
EVENING T-STORMS...MAINLY FOR THE MTNS AND HIGH FOOTHILLS. AT THIS
TIME...T-STORMS WITHIN THE CWFA ARE NOT EXPECTED TO PRODUCE HEAVY
RAIN LIKE THOSE OF THE PAST COUPLE OF WEEKS DUE LARGELY TO LOWER
SPECIFIC HUMIDITY AND PRECIPITABLE WATER VALUES. PORTIONS OF
NORTHEAST/EAST CENTRAL COLORADO MAY NOT SEE ANY PRECIP AT ALL
DURING THIS PERIOD.
&&
.AVIATION...WINDS WERE DRAINAGE EARLY THIS MORNING AS A WK DENVER
CYCLONE IS WEST OF DIA. BOTH THE RAP AND HRRR SHOW SOME STRATUS
DEVELOPING OVER CNTRL WELD COUNTY BY 12Z HOWEVER NEITHER MODEL
SHOWS IT AFFECTING THE AIRPORT AS WINDS STAY SSW. BY LATE MORNING
THE WK CYCLONE IS FCST TO MOVE SE OF THE AIRPORT WITH WINDS
BECOMING NELY BY 18Z AND CONTINUING THRU THE AFTN HOURS. NO TSTMS
ARE EXPECTED THIS AFTN AS ISOLD ACTIVITY SHOULD STAY OVER THE
HIGHER TERRAIN. FOR THIS EVENING WINDS SHOULD TRANSITION BACK TO
DRAINAGE BY 06Z.
&&
.HYDROLOGY...ISOLD HIGH BASED STORMS MAY DEVELOP BY 20Z IN THE
FOOTHILLS HOWEVER THEY WILL ONLY PRODUCE GUSTY WINDS AND LIGHT
RAINFALL.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RPK
LONG TERM....BAKER
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
500 AM EDT FRI AUG 16 2013
.SYNOPSIS...
08Z WATER VAPOR AND H4 RAP ANALYSIS SHOWING AND UPPER LEVEL PATTERN
THAT IS AMPLIFYING INTO THE EASTERN HALF OF THE CONUS. LONGWAVE
TROUGHING IS DIGGING SOUTHWARD TOWARD THE NORTHERN GULF COAST TO OUR
NORTHWEST WHILE WEAK NE TO SW ELONGATED RIDGING HOLDS OVER THE
CENTRAL AND SOUTHERN FL PENINSULA. ABUNDANT COLUMN MOISTURE IS IN
PLACE BETWEEN THESE 2 FEATURES WITH PW OVER 2" WIDESPREAD ACROSS THE
REGION. CLOSER TO THE SURFACE WE FIND A WEAK VERSION OF THE
SUBTROPICAL RIDGE AXIS ALIGNED OVER THE SOUTHERN HALF OF THE
PENINSULA...SUPPRESSED SOUTHWARD BY A SURFACE TROUGH ELONGATED EAST
TO WEST NEAR THE I-10 CORRIDOR.
REGIONAL RADARS SHOW 2 SEPARATE AREAS OF EXPANDING SHOWER ACTIVITY.
THE FIRST IS OVER THE NATURE COAST TO THE NORTH OF PASCO COUNTY IN
CLOSER PROXIMITY TO THE FOCUS ALONG THE SURFACE TROUGH. THE OTHER IS
A BROAD AREA OF SHOWERS AND STORMS MOVING NORTH OUT OF THE SE GULF
INTO OUR COASTAL WATERS. THIS FEATURE IS NOT BEING HANDLED WELL BY
ANY NUMERICAL GUIDANCE SOLUTION THIS MORNING...AND IS THE FIRST
SIGNS OF WHAT WILL LIKELY BE A DIFFICULT FORECAST TO PUT MUCH DETAIL
INTO FOR ABOUT THE NEXT 48 HOURS. WILL DO MY BEST TO EXPLAIN THE
CURRENT FORECAST PHILOSOPHY BELOW.
&&
.SHORT TERM (TODAY THROUGH SUNDAY)...
TODAY...AS MENTIONED ABOVE...A RATHER CHAOTIC UPPER LEVEL PATTERN
OVER THE SE CONUS/GULF OF MEXICO WILL MAKE THE FORECAST MORE
DIFFICULT THAN NORMAL TO PIN DOWN A LOT OF TEMPORAL DETAILS IN TERMS
OF JUST WHEN AND WHERE THE BEST RAINFALL CHANCES WILL BE. CERTAINLY
WOULD APPEAR THAT THE HIGHEST RAIN CHANCES AND SPATIAL COVERAGE OF
SHOWERS/STORMS THROUGH THE DAY WOULD EXIST OVER OUR NORTHERN NATURE
COAST ZONES WHO WILL CONTINUE TO EXIST IN CLOSEST PROXIMITY TO THE
LOW LEVEL FOCUS OF THE SURFACE TROUGH...AND ALSO INCREASING
PROXIMITY TO THE SYNOPTIC SUPPORT ON THE EASTERN EDGE OF THE DIGGING
UPPER TROUGH ALONG THE NORTHERN GULF COAST. THE REST OF THE REGION
WILL SEE AT LEAST CHANCE POPS THROUGH THE DAY DUE SIMPLY TO THE
EXTENT OF COLUMN MOISTURE THAT IS PLACE. THIS MUCH MOISTURE COMBINED
WITH EVEN A LIMITED AMOUNT OF DIURNAL HEATING THROUGH ABUNDANT
CLOUDS SHOULD BE ENOUGH TO BUBBLE UP A SCATTERING OF CONVECTION.
TONIGHT INTO SATURDAY...THE COMBINATION OF THE UPPER LEVEL SUPPORT
OF THE TROUGH AND THE NORTHWARD MOVEMENT OF THE TROPICAL DISTURBANCE
DOWN TOWARD THE YUCATAN PENINSULA IS FORECAST BY JUST ABOUT ALL THE
RELIABLE NUMERICAL GUIDANCE MODELS TO RESULT IN A ZONE OF HEAVY
RAINFALL POTENTIAL FROM THE CENTRAL GULF OF MEXICO NORTH AND
NORTHEAST INTO THE FL PANHANDLE/SOUTHERN GA. AT THIS POINT...IT
APPEARS AS THOUGH OUR FORECAST AREA WILL SEE JUST ENOUGH INFLUENCE
FROM THE UPPER RIDGE TO HOLD THIS BAND GENERALLY OFF TO OUR NORTH
AND NORTHWEST. LEVY/CITRUS WILL BE THE COUNTIES THAT ARE OF LEAST
CONFIDENCE...BUT FOR NOW IT APPEARS THAT EVEN THESE ZONES WILL
ESCAPE THE HEAVIEST AND WIDESPREAD RAINFALL POTENTIAL. THAT BEING
SAID...THE RIDGE OVERHEAD IS CERTAINLY NOT STRONG ENOUGH TO HOLD
BACK THE MORE TYPICAL DIURNAL SEA-BREEZE TYPE CONVECTION. A LIGHT
EAST TO SOUTHEAST FLOW PATTERN WILL FAVOR AFTERNOON/EVENING
CONVECTION ALONG THE FLORIDA WEST COAST AND THIS WILL BE AIDED BY A
FAVORABLE COLUMN MOISTURE PROFILE SUPPORTIVE OF DEEP CONVECTION.
THEREFORE HIGH END CHANCE TO LIKELY POPS WILL EXIST ALONG THE I-75
CORRIDOR DURING THE SECOND HALF OF SATURDAY...BUT TEMPORAL DURATION
OF THE RAINFALL WILL BE MORE TYPICAL OF SUMMER AS OPPOSED TO WHAT
WILL BE OCCURRING TO OUR NW.
FINALLY FOR SUNDAY WE WILL FIND THE UPPER LEVEL PATTERN
DE-AMPLIFYING AND A RETURN TO A MORE CLIMATOLOGICAL ATMOSPHERIC
COLUMN AND FORECAST. MUCH OF THE MORNING SHOULD BE ON THE QUIET SIDE
GIVING WAY TO AN ACTIVE AFTERNOON OR SHOWERS AND STORMS...BUT
NOTHING UNUSUAL FOR THE MIDDLE OF AUGUST.
&&
.LONG TERM (MONDAY THROUGH NEXT THURSDAY)...
AN U/L RIDGE OVER THE WESTERN ATLANTIC WILL EXTEND ACROSS FLORIDA
MONDAY AND WILL WEAKEN SLIGHTLY ON TUESDAY. A STRONG U/L RIDGE OVER
THE SOUTHERN PLAINS WEDNESDAY WILL BEGIN TO BUILD EAST AND WILL
STRENGTHEN THE RIDGE OVER FLORIDA LATE IN THE WEEK. THIS WILL ALLOW
TEMPERATURES TO RUN A FEW DEGREES ABOVE NORMAL EACH DAY THROUGH THE
EXTENDED PERIOD. SURFACE HIGH PRESSURE ALONG THE MID ATLANTIC COAST
MONDAY WILL CREATE EASTERLY FLOW BOUNDARY LAYER FLOW ACROSS THE
PENINSULA WHICH WILL ENHANCE CONVERGENCE ALONG THE WEST COAST SEA
BREEZE BOUNDARY...WITH SCATTERED AFTERNOON THUNDERSTORMS ACROSS THE
FORECAST AREA...AND NUMEROUS THUNDERSTORMS ALONG THE COASTAL
COUNTIES FROM THE TAMPA BAY AREA SOUTH TO FORT MYERS. SLIGHTLY
DRIER AIR ALOFT WILL ADVECT OVER WEST CENTRAL FLORIDA FROM THE EAST
ON TUESDAY WHICH WILL DECREASE AREAL COVERAGE OF THUNDERSTORMS...BUT
EASTERLY FLOW WILL PERSIST WHICH WILL AGAIN ENHANCE THUNDERSTORM
ACTIVITY ALONG THE WEST COAST SEA BREEZE OVER THE COASTAL COUNTIES
DURING THE MID TO LATE AFTERNOON. DEEP LAYER MOISTURE WILL INCREASE
ON WEDNESDAY WITH CONTINUED EASTERLY BOUNDARY LAYER FLOW WITH
SCATTERED TO NUMEROUS AFTERNOON THUNDERSTORMS WITH HIGHEST POPS
ALONG THE COASTAL COUNTIES. PRESSURE GRADIENT WILL RELAX ON
THURSDAY WHICH WILL ALLOW THE WEST COAST SEA BREEZE BOUNDARY TO PUSH
FURTHER INLAND WITH SCATTERED AFTERNOON THUNDERSTORMS ACROSS ALL OF
WEST CENTRAL AND SOUTHWEST FLORIDA. AN ISOLATED PULSE SEVERE
THUNDERSTORM ARE POSSIBLE EACH AFTERNOON...HOWEVER THE MAIN THREAT
FROM STORMS WILL BE LOCALLY HEAVY RAIN...FREQUENT CLOUD TO GROUND
LIGHTNING...AND WIND GUSTS OF 35 TO 45 MPH.
&&
.AVIATION...
SCT LCL BKN 020-025 DEVELOPING AROUND SUNRISE THIS MORNING LIFTING
TO 030-035 THIS AFTERNOON. SHOWERS AND THUNDERSTORMS VCNTY ALL
TERMINALS...WITH GREATEST AREAL COVERAGE THIS AFTERNOON...WITH LCL
MVFR CIGS AND IFR VSBYS.
&&
.MARINE...
THE EASTERN GULF OF MEXICO WILL RESIDE BETWEEN THE SUBTROPICAL
SURFACE RIDGE TO OUR EAST...AND A BROAD AREA OF SURFACE TROUGHING TO
OUR WEST. JUST HOW STRONG OUR LOCAL GRADIENT AND WINDS END UP BY
SATURDAY WILL DEPENDING ON THE STRENGTH OF THIS SURFACE TROUGH.
CURRENTLY NOT EXPECTING WINDS OR SEAS TO REACH HEADLINE
CRITERIA...ESPECIALLY OVER THE NEAR SHORE WATERS. LATER IN THE
WEEKEND AND INTO THE EARLY PORTION OF NEXT WEEK...THE SURFACE RIDGE
WILL LIFT WELL NORTH OF THE REGION PROVIDING A MORE CONSISTENT
EASTERLY FLOW ACROSS THE FORECAST WATERS.
&&
.FIRE WEATHER...
ABUNDANT TROPICAL MOISTURE WILL OVERSPREAD THE REGION THROUGH THE
WEEKEND AND KEEP RELATIVE HUMIDITY VALUES WELL ABOVE CRITICAL
LEVELS. NO SIGNIFICANT FIRE WEATHER CONCERNS ARE CURRENTLY
ANTICIPATED.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 89 78 93 79 / 50 30 50 30
FMY 92 78 93 77 / 40 30 60 30
GIF 91 75 94 74 / 60 30 50 30
SRQ 90 78 92 76 / 40 30 50 30
BKV 89 74 92 74 / 50 40 60 30
SPG 90 80 93 80 / 50 30 50 30
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/MARINE/FIRE WX...MROCZKA
LONG TERM/AVIATION...OGLESBY
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
310 AM EDT Fri Aug 16 2013
.SHORT TERM (Now through Saturday)...
Issued at 305 AM EDT Fri Aug 16 2013
The main challenge for today will be precipitation chances over
south central KY. Weak convection formed Thurs due to forcing of an
upper level trough and sfc convergence along an inverted trough over
central TN. A line of showers and isld t-storms resulted Thurs
afternoon/evening and has been slowly dissipating and drifting
northward during the early morning hours. Left over sprinkles may
drift into our south central KY counties this morning around and
just after sunrise. A better chance of rain looks to arrive this
afternoon for south central KY if the inverted sfc trough can drift
far enough northward as the 0Z NAM and 3Z RAP suggest it will.
Expect weakly forced showers and isld t-storms to re-fire along the
boundary by mid to late afternoon and again weaken and diminish
after sunset. Although did increase POPs to 30% along the KY/TN
border, there is still some doubt that the boundary will not make it
this far north so will need to monitor closely today. Went a few
degrees cooler than MOS guidance for high temps and MOS guidance was
a few degrees too warm for Thurs highs. This puts the area in the
upper 70s to around 80 for highs this afternoon.
Tonight expect showers/storms to diminish early over south central
KY and become more focused to our west and south overnight as an
upper level wave drops down into the broad Midwest trough forming a
closed low over the mid Mississippi River Valley by Sat afternoon.
It appears that this feature may help pull the inverted sfc trough
back northward over central KY for Sat providing a better focus for
showers/t-storms. Although wind fields and overall forcing still
look meager, perhaps better overall coverage of convection can be
achieved over central KY Sat afternoon. Any storms that develop
today or Sat should not pose a severe weather threat and would be
brief/weak in nature.
Temperatures tonight should fall into the upper 50s and lower 60s
for lows. Highs Saturday afternoon will warm into the upper 70s and
lower 80s with the warmer spots located over southern Indiana which
only has a 20% chance of rain.
.LONG TERM (Saturday Night through Thursday)...
Issued at 300 AM EDT FRI Aug 16 2013
The extended forecast, starting late Saturday, will feature a
wholesale change in the configuration of the jet stream. The polar
jet, which has for several weeks now been locked in a cyclonic flow
around the Great Lakes, will retreat north into a zonal flow along
or just north of the Canadian Border. This pattern is common in
July, during high summer, and will allow a substantial late summer
warmup for the upper Midwest and the Great Lakes.
As this jet lifts north however, a digging shortwave now moving
south across Kansas will help to elongate a residual trough over the
Lower Ohio Valley. Indeed, both the NAM and the GFS closes off this
trough and creates a shallow cutoff low over the Missouri Bootheel
late Saturday. This feature will lift northeast and become absorbed
into the westerlies over Ohio by late Monday.
A tropical disturbance, now over the Yucatan Peninsula, is forecast
to slowly move northwest and may develop in to a tropical storm early
next week, Regardless of the eventual path of this feature, rich
Gulf moisture will stream northeast out of the western Gulf into the
eastern Tennessee Valley and the southern Appalachians from Sunday
into at least Tuesday of next week.
On Sunday and Monday, central Kentucky will lie in a transition
region between mostly clear skies and subsidence across northern
Indiana and the northwest fringes of an increasingly humid airmass
developing over the southern Appalachians. Weak to moderate
instability both Sunday and Monday afternoon will lead to isolated
to scattered showers and thunderstorms, especially along and south
of the Bluegrass Parkway. Think that coverage may be best Sunday
afternoon, aided by the presence of a weak 850mb circulation over
central Kentucky and a possible inverted trough extending northwards
across the Tennessee Valley. Any convection that does develop Sunday
or Monday will be diurnally driven, dissipating in the evening
hours.
Winds early next week will stay quite light. Temperatures, moderated
by possible cloudiness and the continued presence of troughing, will
remain below normal, with highs in the lower 80s by day and the mid
60s at night.
Heights begin to rise over the Lower Ohio Valley Tuesday as the last
vestiges of the eastern trough exits. Weak subsidence associated
with a slowly eastward propagating 500mb ridge over the southern plains will
most likely keep Tuesday through Thursday dry, as is shown in the
preferred ECMWF. We will experience typical late summer weather with
very light winds and pressure gradients, coupled with moderate
humidities and temperatures that, by Thursday afternoon may warm
into the upper 80s to around 90.
&&
.AVIATION (06Z TAF Update)...
Issued at 115 AM EDT Fri Aug 16 2013
VFR conditions are expected for this TAF period. An inverted sfc
trough over TN and an upper level trough will continue to spark weak
convection mainly to the south of BWG, however, can`t rule out a
sprinkle or shower at BWG today. Low level moisture return looks to
scant to make a VCSH shower mention in the TAF at this time. Plus,
a drier NE wind will continue at the terminal further inhibiting
shower chances. Winds will continue out of the NE at all terminals
through the TAF period with max winds between 6-8 kts this afternoon.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Short Term........AMS
Long Term.........JSD
Aviation..........AMS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
501 AM CDT FRI AUG 16 2013
.UPDATE...
ISSUED AT 501 AM CDT FRI AUG 16 2013
KUEX INDICATES SHOWER AND THUNDERSTORM ACTIVITY HAS DEVELOPED OVER
PORTIONS OF CENTRAL KANSAS...JUST SOUTH OF OUR CWA. RAP ANALYSIS
DATA INDICATES A SUBTLE MID LEVEL PERTURBATION IS ADVANCING SOUTH
FROM CENTRAL NEBRASKA INTO KANSAS...WITH WATER VAPOR IMAGERY ALSO
INDICATING A SUBTLE VORT MAX MOVING INTO KANSAS. BASED ON THE
POSITION OF THE SUBTLE VORT MAX ON WATER VAPOR IMAGERY...AND THE
POSITION OF THE MID LEVEL PERTURBATION FROM RAP ANALYSIS DATA...IT
APPEARS THE MID LEVEL TROUGH AXIS IS OVER OUR CWA NOW...WITH WEAK
MID LEVEL THERMAL ADVECTION AND DPVA AHEAD OF THIS TROUGH AXIS
LIKELY PROMOTING JUST ENOUGH OMEGA FOR PRECIPITATION PRODUCTION TO
OUR SOUTH. IN ADDITION TO THE MID LEVEL PERTURBATION...A SUBTLE
SURFACE TROUGH...PERHAPS A WEAK LOW LEVEL BAROCLINIC ZONE...IS
ALSO EVIDENT EXTENDING FROM WESTERN KANSAS INTO CENTRAL AND EAST-
CENTRAL KANSAS. RAP ANALYSIS SUGGESTS WEAK ISENTROPIC UPGLIDE IN
EXISTENCE ALONG/NEAR THE 295K SURFACE ACROSS THIS BOUNDARY...WITH
THE ONGOING SHOWER AND THUNDERSTORM ACTIVITY OCCURRING ALONG THIS
AXIS OF ISENTROPIC UPGLIDE. AT THIS TIME IT APPEARS THE WEAK MID
LEVEL OMEGA AND LOW LEVEL THERMAL ADVECTION RESPONSIBLE FOR THE
ONGOING PRECIPITATION PRODUCTION SHOULD REMAIN JUST SOUTH OF OUR
CWA...ALTHOUGH NOT BY MUCH...THUS ALLOWING FOR A CONTINUED DRY
FORECAST THROUGH THIS MORNING. THAT BEING SAID...THE ONGOING
SHOWER AND THUNDERSTORM ACTIVITY WILL NEED TO BE MONITORED TO MAKE
SURE IT DOES NOT SNEAK NORTHWARD INTO EXTREME SOUTHERN PORTIONS OF
OUR CWA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 331 AM CDT FRI AUG 16 2013
OVERNIGHT MAP ANALYSIS INDICATES A LONGWAVE MID TO UPPER LEVEL
TROUGH IN EXISTENCE ACROSS THE EASTERN HALF OF THE CONUS...AND A
RIDGE OVER THE WEST. MID TO UPPER LEVEL JET ENERGY EXTENDS FROM
THE NORTHWESTERN CONUS...NORTHEAST INTO SOUTHWESTERN CANADA...THEN
SOUTHEAST ACROSS THE CENTRAL CONUS...AND FINALLY EAST AND
EVENTUALLY NORTHEAST ACROSS PORTIONS OF THE SOUTHEASTERN CONUS AND
EVENTUALLY THE EAST/NORTHEASTERN CONUS. MID TO UPPER LEVEL FLOW
OVER THE CENTRAL PLAINS REMAINS FROM THE NORTHWEST AS A RESULT BUT
IS NOT PARTICULARLY STRONG...ONLY MAXING OUT AT AROUND 45KTS NEAR
200MB PER 00Z SOUNDING DATA FROM KLBF AND KOAX. THE AFOREMENTIONED
MID LEVEL LONGWAVE RIDGE AND TROUGH CAN ALSO BE SEEN ON WATER
VAPOR IMAGERY...WITH INCREASED VALUES OF MID LEVEL MOISTURE ALSO
NOTED FLOWING ALONG THE AFOREMENTIONED JET AXIS. AT THE SURFACE A
SUBTLE TROUGH IS NOTED EXTENDING FROM WESTERN KANSAS INTO PORTIONS
OF NORTHEASTERN KANSAS. THE LOW LEVEL WIND FIELD ACROSS OUR AREA
REMAINS FROM THE EAST/NORTHEAST AS A RESULT.
GUIDANCE FROM THE NAM...OPERATIONAL GFS...EC...AND SREF-MEAN ALL
SUGGEST THE WESTERN CONUS LONGWAVE TROUGH WILL DRIFT EAST SOMEWHAT
THROUGH THE NEXT 24 HOURS. THE RESULTANT LACK IN OVERALL KINEMATIC
FORCING SUGGESTS DRY CONDITIONS SHOULD BE OBSERVED ACROSS OUR AREA
TODAY AND TONIGHT. THE ONLY OPPORTUNITY FOR MEASURABLE
PRECIPITATION MAY BE ACROSS OUR SOUTHWEST 06-12Z SATURDAY AS WEAK
LOW LEVEL THERMAL ADVECTION ALONG THE AXIS OF ~30KT 850MB JET AXIS
PROMOTES ISOLATED TO SCATTERED SHOWER AND THUNDERSTORM ACTIVITY
OVER THE CENTRAL HIGH PLAINS. THERE IS AN OUTSIDE CHANCE SOME OF
THIS ACTIVITY COULD CREEP INTO OUR FAR SOUTHWESTERN CWA BUT AT
THIS TIME CONFIDENCE IS NOT HIGH ENOUGH TO INSERT POPS INTO THE
SHORT TERM FORECAST PERIOD AND AS A RESULT...DRY CONDITIONS ARE
CURRENTLY FORECAST THROUGH 12Z SATURDAY.
ALTHOUGH CONFIDENCE WITH RESPECT TO MEASURABLE PRECIPITATION BEING
REALIZED ACROSS OUR CWA IS VERY LOW...CONFIDENCE WITH RESPECT TO
INCREASING CLOUD COVER ACROSS OUR AREA TONIGHT INTO EARLY SATURDAY
IS INCREASING. GUIDANCE FROM THE NAM AND OPERATIONAL GFS...AS WELL
AS THE MET AND MAV...SUGGEST THE AFOREMENTIONED LOW LEVEL THERMAL
ADVECTION ALONG THE AXIS OF THE LOW LEVEL JET STREAK SHOULD BE
STRONG ENOUGH TO PROVIDE ISENTROPIC UPGLIDE AND
SATURATION...PRIMARILY ALONG THE 300-305K SURFACES. GIVEN THESE
SOLUTIONS...WENT AHEAD AND INCREASED CLOUD COVER SIGNIFICANTLY
ACROSS MUCH OF OUR CWA TONIGHT INTO EARLY SATURDAY MORNING. IN
ADDITION TO THE STRATUS...NEAR-ZERO LOW LEVEL DEW POINT
DEPRESSIONS AND A LIGHT SOUTHEAST LOW LEVEL WIND FIELD COULD ALSO
PROMOTE FOG DEVELOPMENT ACROSS PORTIONS OF THE CWA TOWARDS
DAYBREAK SATURDAY. GIVEN THIS POTENTIAL...WENT AHEAD AND INSERTED
PATCHY FOG INTO THE GRIDS FOR EARLY SATURDAY MORNING.
PERSISTENT CLOUD COVER THROUGH MID TO LATE THIS MORNING...ALONG
WITH A PERSISTENT EASTERLY COMPONENT TO THE LOW LEVEL WIND
FIELD...WILL LIKELY KEEP TEMPERATURES ON THE COOL SIDE TODAY.
GUIDANCE FROM THE MET...MAV...AND ECS ALL SEEM TO HAVE A GOOD
HANDLE ON THIS AND TAKING AN EVEN-AVERAGE OF THESE THREE SETS OF
GUIDANCE PROVIDES AFTERNOON HIGHS IN THE MID 70S ACROSS THE
NORTHEASTERN TWO-THIRDS OF OUR CWA...AND CLOSER TO 80 ACROSS OUR
SOUTHWEST. LITTLE CHANGE IN THE LOW LEVEL AIRMASS AND INCREASING
CLOUD COVER...MUCH LIKE WE ARE OBSERVING THIS MORNING...SHOULD
PROVIDE SIMILAR OVERNIGHT LOW TEMPERATURES TONIGHT WHEN COMPARED
TO EARLY THIS MORNING. GIVEN THIS...WENT AHEAD WITH EARLY SATURDAY
MORNING TEMPERATURES NEAR 60 FOR MOST LOCATIONS ACROSS THE CWA.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 331 AM CDT FRI AUG 16 2013
A PATTERN CHANGE APPEARS TO BE ON THE WAY THAT WILL RESULT IN
DRIER WX AND TEMPS MORE TYPICAL OF SUMMER. THE MID-SUMMER BREAK
FOR A/C UNITS WILL END AS MULTIPLE DAYS OF 90F HEAT ARE IN THE
OFFING.
ALOFT: NOW THAT THE AK-CANADA HIGH LATITUDE BLOCKING IS FINALLY
BREAKING DOWN...THE FAIRLY HIGH AMPLITUDE ROCKIES RIDGE/ERN USA
TROF COMBO THAT HAS DOMINATED THE WX FOR THE PAST TWO WEEKS WILL
DE-AMPLIFY AS WELL. THE WESTERLIES WILL BECOME ZONAL AGAIN OVER
CANADA AND THE NRN USA. MEANWHILE...THE TROF OVER THE E PAC WILL
CLOSE OFF AND BECOME CUT-OFF...LINGERING OVER CA FOR THE NEXT
SEVERAL DAYS. THIS COMBINED WITH THE ERN USA TROF LIFTING OUT WILL
ALLOW THE SUBTROPICAL HIGH TO EXPAND ACROSS MOST OF THE CONUS. THE
WARMER TEMPS ALOFT SHOULD PUT A CAP ON PCPN POTENTIAL FOR SEVERAL
DAYS.
SFC: EXPANSIVE HIGH PRES THAT HAS BEEN PARKED OVER THE OH VALLEY
WILL GRADUALLY REPOSITION ITSELF OVER THE WRN ATLANTIC...BUT IT
WILL STILL EXTEND BACK INTO THE ERN USA. AS A SERIES OF LOWS
TRACKS ACROSS CANADA...A LEE-SIDE TROF WILL DEVELOP. THE INCREASED
PRES GRADIENT WILL RESULT IN A BIT MORE WIND THAN WE/VE SEEN FOR
THE LAST COUPLE WEEKS. THE NEXT COOL FRONTAL PASSAGE IS ADVERTISED
FOR NEXT THU AFTN-NGT.
THE 00Z EC AND GFS LOOK NOTHING ALIKE AT THE SFC AT 168 HRS /00Z
FRI/. THE GFS HAS A STRONGER SHRTWV TROF OVER THE PAC NW /H5 HGTS
40-60 M LOWER/ WHICH RESULTS IN A 997 MB LOW OVER ND VS. THE EC
1019 MB HIGH OVER LAKE WINNIPEG. THE 18Z GFS WAS MORE SUPPORTIVE
OF THE EC SOLUTION. SO THE 00Z RUN WAS NOT FACTORED INTO THIS FCST
BEYOND TUE.
THE DAILY DETAILS...
SAT: WIDESPREAD LOW STRATUS APPEARS LIKELY VIA MODEL CROSS
SECTIONS. SINCE IT/S CURRENTLY IN-PLACE AND THE FCST AREA WILL
REMAIN ON THE WRN FRINGE OF A SIZABLE POOL OF COOL AIR IN THE LOW-
LVLS...IT WILL BE HARD TO GET RID OFF UNTIL THE THERMAL TROF
RELEASES ITS GRIP WHICH WILL PROBABLY HAPPEN SUN.
SO EXPECT A CLOUDY START MOST AREAS WITH SLOW BUT GRADUAL
IMPROVEMENT. THERE WILL PROBABLY BE SOME AREAS THAT DON/T
COMPLETELY CLEAR OUT UNTIL MID-LATE AFTN. CAN FORESEE PARTS OF THE
FCST AREA NOT REACHING 80F.
SAT NGT: THE PRES GRADIENT WILL KEEP WINDS 7-15 MPH. SO DON/T
ENVISION FOG BEING A PROBLEM...BUT GIVEN THAT THE STRATUS/HIGH
LOW-LVL MSTR MAY NOT COMPLETELY MIX OUT SAT AFTN...LOW CLOUDS
SHOULD REFORM. JUST NOT SURE TO WHAT EXTENT.
SUN: THE DAY MAY START WITH STRATUS COVERING ALL OR PART OF THE
FCST AREA. FCST SOUNDINGS SUGGEST DRIER AIR WILL MIX DOWN. SO
IMPROVEMENT SHOULD BE MORE PERMANENT. SHOULD BE AN ESPECIALLY NICE
DAY FOR OUTDOOR ACTIVITIES BUT WITH S WINDS GUSTING UP TO 25 MPH.
MON-WED: SUNNY AND DRY AS WE SEE IT NOW. HIGH TEMPS WILL AVERAGE
ABOUT 5F WARMER THAN NORMAL.
THE NEXT OPPORTUNITY FOR TSTMS IS SLATED FOR THU AFTN-EVNG WITH A
COOL FRONTAL PASSAGE. WITH SUCH A WARM LOOK TO THE HGTS ALOFT...
CAPPING WILL PROBABLY LIMIT COVERAGE TO JUST AN ISOLATED TSTM OR
TWO.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1253 AM CDT FRI AUG 16 2013
IFR CONDITIONS FORECAST UNTIL 15Z...VFR CONDITIONS 15-05Z...AND
MVFR CONDITIONS TO FINISH THE TAF PERIOD.
STRATUS HAS OVERTAKEN MUCH OF SOUTH CENTRAL NEBRASKA WITH A
CEILING BETWEEN 500 AND 700FT AGL BEING REPORTED THROUGH MANY
LOCATIONS. GUIDANCE SUGGESTS SUCH CEILINGS WILL BE OBSERVED AT GRI
THROUGH EARLY TO MID MORNING FRIDAY...THUS THE IFR FORECAST UNTIL
15Z. THERE MAY ALSO BE SOME VISIBILITY RESTRICTION IN FOG THROUGH
EARLY TO MID FRIDAY MORNING AS WELL...BUT AT THIS TIME IT IS
BELIEVED ANY VISIBILITY RESTRICTION WILL NOT DROP MUCH BELOW 5SM.
STRATUS IS EXPECTED TO BREAK APART AND LIFT BY EARLY TO MID
MORNING WITH VISIBILITY ALSO BEING FULLY RESTORED...THUS THE VFR
FORECAST STARTING 15Z. CONFIDENCE IS HIGH THAT VFR CONDITIONS WILL
BE REALIZED BY NO LATER THAN 15Z...BUT THIS WILL NEED TO BE
MONITORED THROUGH THE NEXT 10 OR SO HOURS. STRATUS IS CURRENTLY
EXPECTED TO REDEVELOP FRIDAY NIGHT INTO SATURDAY MORNING...HOWEVER
AT THIS TIME THIS CEILING IS NOT EXPECTED TO DROP BELOW 1000FT
AGL...SO FOR NOW WILL GO WITH MVFR CONDITIONS STARTING 05Z. THIS
WILL ALSO NEED TO BE CLOSELY MONITORED IN CASE IT BECOMES
INCREASINGLY EVIDENT CONDITIONS WILL DETERIORATE TO BELOW MVFR
LEVELS. THE SURFACE WIND WILL REMAIN LIGHT THROUGH THE TAF
PERIOD...REMAINING FROM THE EAST/SOUTHEAST FOR THE MOST PART.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...BRYANT
SHORT TERM...BRYANT
LONG TERM...HALBLAUB
AVIATION...BRYANT
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1238 AM CDT FRI AUG 16 2013
.SYNOPSIS...
ISSUED AT 333 PM CDT THU AUG 15 2013
CURRENTLY...AN UPPER LEVEL DISTURBANCE IS MOVING SOUTH-SOUTHEAST
ACROSS SOUTH DAKOTA IN NORTHWEST FLOW ALOFT. AN UPPER LEVEL RIDGE
EXTENDS NORTHWARD FROM THE FOUR CORNERS REGION TO SASKATCHEWAN AND
AN UPPER LEVEL LOW EXISTS OVER QUEBEC. A SURFACE BOUNDARY
CURRENTLY EXTENDS NORTHWESTWARD FROM FRONTIER COUNTY THROUGH
GARDEN COUNTY AND INTO NORTHWESTERN NEBRASKA. ALSO...LOW CLOUDS
HAVE BEEN PERSISTENT OVER PARTS OF NORTH-CENTRAL NEBRASKA TODAY.
&&
.UPDATE...
ISSUED AT 932 PM CDT THU AUG 15 2013
UPDATED TO REMOVE REMAINING PRECIP CHANCES AND TO FINE TUNE
AREAS/PATCHY FOG GRIDS. OTHERWISE REMAINDER OF THE FCST LOOKS GOOD.
UPDATE ISSUED AT 654 PM CDT THU AUG 15 2013
HAVE UPDATED TO REMOVE PRECIPITATION CHANCES FOR ALL BUT THE FAR
SOUTHERN PORTION OF THE FCST AREA THIS EVENING BASED ON LATEST
SATELLITE/RADAR TRENDS AND GUIDANCE FROM SHORT RANGE MODELS. THE
BIGGEST FCST CHALLENGE TONIGHT WILL BE TIMING THE ONSET OF FOG
ALONG AND EAST OF THE HIGHWAY 83 CORRIDOR. SOME VISIBILITIY
RESTRICTIONS ALREADY ALONG THE HIGHWAY 281 CORRIDOR IN HOLT COUNTY
BASED ON OBS AND WEB CAMS. WHILE THERE MAY BE SOME DECREASE IN
CLOUDS BRIEFLY IN THE NORTH CENTRAL ARAS...EXPECT THEM TO COME
BACK IN LATE THIS EVENING AND DURING THE EARLY MORNING HOURS AS
THE FCST AREA EXPERIENCES INCREASING SUBSIDENCE FROM EXITING UPPER
PV ANOMALY WHILE MOIST BUT LIGHT UPSLOPE FLOW CONTINUES. PREVIOUS
FCST HAD THIS ALERADY...BUT HAVE MOVED UP THE TIMING A BIT IN THE
EASTERN PORTION OF THE FCST AREA.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 333 PM CDT THU AUG 15 2013
STARTING TO SEE SOME CUMULUS DEVELOPMENT ALONG STATIONARY SURFACE
BOUNDARY EXTENDING TO THE NW FROM FRONTIER COUNTY THROUGH OGALLALA
AND NWWD. BELIEVE THIS WOULD BE THE BEST AREA FOR THUNDERSTORM
DEVELOPMENT THIS AFTERNOON...WITH ANY STORMS MOVING SOUTHEASTWARD
AT AROUND 20 KTS. MODELS INDICATE 0-6 KM SHEAR OF 30-35 KTS
ALTHOUGH SPC MESOANALYSIS DATA IS SHOWING SHEAR UNDER 30 KTS AS OF
20Z. THERE MAY BE A FEW ISOLATED SEVERE STORMS THIS AFTN/EVE...BUT
THE BEST CHANCE WOULD BE SOUTH OF I-80. HAVE TRIMMED POPS AND
THUNDERSTORM COVERAGE A BIT ACROSS THE AREA TONIGHT BASED ON
LATEST MODEL DATA AND TRENDS. HRRR MODEL FROM 18Z HAS A FEW STORMS
JUST WEST OF NORTH PLATTE AND AREAS SE...MOVING SE TONIGHT. EMC
WRF MODEL HAS A FAIR AMOUNT OF CONVECTION NORTH TO THE SD BORDER
HOWEVER...ALTHOUGH ITS NOT AS LIKELY. THUNDERSTORMS SHOULD COME TO
AN END IN THE EVENING ACROSS THE AREA AS THE UPPER LEVEL WAVE
MOVES THROUGH THE REGION. MODELS ARE POINTING TOWARD MORE FOG AND
LOW STRATUS TONIGHT...ESPECIALLY CENTRAL AND EAST. HAVE INCLUDED
FOG IN THE FORECAST FOR MOST OF THE AREA. TOMORROW...AFTER LOW
CLOUDS AND FOG HAVE DISSIPATED...FAIR SKIES AND TEMPS IN THE MID
70S EAST TO UPPER 80S WEST ARE EXPECTED.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 333 PM CDT THU AUG 15 2013
MID TERM...FRIDAY NIGHT THROUGH SUNDAY...RIDGING WILL CONTINUE TO
BUILD ACROSS THE CENTRAL PLAINS FRIDAY NIGHT THROUGH SATURDAY
NIGHT...WITH TEMPERATURES THE MAIN FORECAST CHALLENGE...FOLLOWED BY
PRECIPITATION CHANCES IN THE FAR WEST SUNDAY AFTERNOON. FOR FRIDAY
NIGHT...SURFACE HIGH PRESSURE WILL DRIFT EAST INTO THE MIDDLE
MISSISSIPPI VALLEY WITH A LEE SIDE TROUGH BEGINNING TO DEEPEN ACROSS THE
FRONT RANGES OF COLORADO AND WYOMING. SRLY WINDS WILL BEGIN TO
INCREASE LATE FRIDAY IN RESPONSE...AND ARE NOT EXPECTED TO TOTALLY
DECOUPLE FRIDAY NIGHT. THIS WILL LEAD TO SLIGHTLY WARMER MIN TEMPS
SATURDAY MORNING COMPARED TO FRIDAY MORNING. THE MET AND MAV
GUIDANCE ARE IN DECENT AGREEMENT WITH LOWS SATURDAY MORNING SO A
BLEND WILL BE UTILIZED...THEN SCALED UPWARD A DEGREE OR TWO DUE TO
INCREASED MIXING. MAV AND MET GUIDANCE TEMPS DIVERGE ON
SATURDAY...WITH THE MAV 3 TO 6 DEGREES COOLER THAN THE MUCH WARMER
MET. UTILIZED THE BIAS CORRECTED CONSALL GUIDANCE FOR HIGHS
SATURDAY...WHICH RESULTED IN A COMPROMISE BETWEEN THE MET AND MAV
NUMBERS. THIS LED TO HIGHS IN THE MIDDLE 80S IN THE EASTERN CWA...TO
THE LOWER 90S IN THE PANHANDLE...WHERE DEW POINTS IN THE LOWER 50S
ARE EXPECTED SAT AFTERNOON. FOR SUNDAY...HIGHS WILL MIRROR SATURDAYS
FCST...WITH THE EXCEPTION OF THE EASTERN ZONES WHERE SLIGHTLY WARMER
TEMPS ARE EXPECTED THANKS TO WARMER H85 AIR. HIGHS SUNDAY WILL RANGE
FROM THE UPPER 80S TO LOWER 90S IN THE PANHANDLE AND FAR WEST. BY
SUNDAY AFTERNOON...THE LATEST NAM IS HINTING AT BREAKING DOWN THE
RIDGE AND INITIATING CONVECTION ACROSS THE PANHANDLE AND FAR WESTERN
ZONES LATE SUNDAY AFTERNOON. THE LATEST GFS...KEEPS THIS CONVECTION
CONFINED TO THE FRONT RANGES OF COLORADO AND WYOMING...THANKS TO
VERY WEAK MID LEVEL STEERING WINDS. INHERITED FCST WAS DRY SUNDAY
AFTERNOON...AND INTEND TO KEEP IT THAT WAY...EVEN IN LIGHT OF THE
LATEST 12Z NAM SOLN.
LONG TERM...SUNDAY NIGHT THROUGH THURSDAY...THERE ARE TWO SCHOOLS
OF THOUGHT WITH THE EXTENDED FCST...A...DRY AND VERY WARM CONDS
WILL PERSIST WELL INTO THE MIDDLE OF NEXT WEEK-12Z GFS...AND B...A
BREAK DOWN IN THE RIDGE ACROSS THE CENTRAL CONUS LEADING TO COOLER
AND WETTER CONDS ACROSS THE AREA-ECMWF. GLANCING AT LAST NIGHTS
ENSEMBLES...THE MEAN NCEP ENSEMBLE MEAN HAS A BREAKDOWN IN THE
WESTERN CONUS RIDGING EARLY IN THE WEEK WITH A FAIRLY ACTIVE
PATTERN DEVELOPING BY MIDWEEK. IN CONTRAST...THE OPERATIONAL GFS
FROM THIS MORNING HAS A CLOSED LOW OVER THE CENTRAL CA COAST. THE
LATTER SOLN...WOULD TEND TO FAVOR A DRY AND WARMER FCST AS RIDGING
WILL AMPLIFY DOWNSTREAM OF THE CLOSED CA LOW. NO SURPRISE...THE
LATEST MEX GUIDANCE FROM THIS MORNING HAS LOWER TO MIDDLE 90S FOR
HIGHS NEXT WEEK WITH DRY CONDS EXPECTED. SINCE THE OPERATIONAL GFS
IS KIND OF AN OUTLIER WITH THE ENSEMBLE FCSTS...WILL FAVOR COOLER
TEMPS IN THE 80S TO LOWER 90S FOR TEMPS NEXT WEEK. AS FOR PCPN
CHANCES...CAN`T SEE MORE THAN A 20 PCT CHANCE TOWARD THE MIDDLE OF
NEXT WEEK...AS WEAK DYNAMICS WILL CONTINUE WELL INTO NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1237 AM CDT FRI AUG 16 2013
MAIN AVIATION FCST CHALLENGE WILL BE GEOGRAPHICAL EXTENT AND
DURATION OF FOG/LOW CLOUDS INTO THE MORNING HOURS. KONL IS DOWN TO
AROUND 1/2SM FOR THE LAST HOUR. CIGS AT KONL...KANW AND KTIF IN THE
LIFR RANGE. FURTHER SOUTH KLBF NOW DOWN TO 4SM. FCST WILL FOLLOW
THE IDEA THAT LOWEST VSBYS /1SM RANGE AND BELOW/ WOULD OCCUR ON
THE WESTERN FRINGE OF STRATUS AS IS TYPICALLY THE CASE.
TIMING OF LOW CLOUD/FOG BURNOFF ALWAYS TOUGH THIS TIME OF YEAR WITH
MINIMAL MECHANICAL MIXING OCCURRING INITIALLY. WILL GO FOR A LATE
MORNING RETURN TO VFR CONDITIONS.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JWS
SYNOPSIS...KNUTSVIG
SHORT TERM...KNUTSVIG
LONG TERM...CLB
AVIATION...ROBERG
AREA FORECAST DISCUSSION
NWS TULSA OK
1159 PM CDT THU AUG 15 2013
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
SHOWERS AND THUNDERSTORMS CONTINUE TO PUSH ACROSS PARTS OF
NORTHEAST OKLAHOMA TONIGHT. WILL KEEP PRECIP MENTION AT TUL/RVS.
BROKEN/OVERCAST SKIES SHOULD CONTINUE TONIGHT INTO FRIDAY MORNING
WITH A SCATTERED MID LAYER CLOUD DECK FOR THE AFTERNOON/EVENING
HOURS. WINDS ARE EXPECTED TO BE BREEZY AND VARIABLE WITH THE MCS
TONIGHT OTHERWISE LIGHT OUT OF THE EAST TO SOUTHEAST. VFR
CONDITIONS SHOULD PERSIST...WITH POSSIBLE MVFR CONDITIONS WITHIN
THE MCS OVER NORTHEAST OKLAHOMA.
&&
.PREV DISCUSSION... /ISSUED 902 PM CDT THU AUG 15 2013/
DISCUSSION...
MCS OVER SOUTH CENTRAL KANSAS IS ABOUT TO PUSH INTO NORTHERN
OKLAHOMA THIS EVENING. THE SYSTEM IS NO LONGER SEVERE...WITH THE
STRONGEST MEASURED WIND OVER THE PAST HOUR OR SO AT 35 MPH. THE
PRIMARY MECHANISM DRIVING THIS SYSTEM IS THE COLD POOL LIFTING
MODERATELY UNSTABLE AIR ON THE ORDER OF 1000-2000 J/KG OF
MLCAPE...AND THIS INSTABILITY IS PRIMARILY CONFINED WEST OF
HIGHWAY 75. AN 850MB RIDGE RESIDES OVER EASTERN OKLAHOMA...SO
THERE IS NOT THAT TYPICAL LOW LVL JET FEEDING INTO THIS SYSTEM.
THEREFORE...THE MCS WILL CONTINUE SOUTH...MAINLY TO THE WEST OF
HIGHWAY 75 WHERE THE INSTABILITY IS...AND LIKELY WEAKEN WITH TIME AS
WE GO INTO THE NIGHT AS THE HRRR MODEL SUGGESTS. UPDATED PRODUCTS
HAVE BEEN SENT.
LACY
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 63 84 62 87 / 40 20 0 0
FSM 62 85 62 89 / 10 10 0 0
MLC 62 84 61 89 / 20 20 10 10
BVO 61 82 59 85 / 60 20 0 0
FYV 54 81 55 83 / 10 10 0 0
BYV 56 79 57 82 / 0 10 10 10
MKO 60 84 61 87 / 20 20 0 0
MIO 59 81 58 83 / 20 10 0 0
F10 62 83 62 87 / 30 20 10 0
HHW 62 87 63 89 / 10 20 10 0
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
AVIATION...20
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
539 AM EDT FRI AUG 16 2013
.SYNOPSIS...
A WEDGE OF COOL HIGH PRESSURE WILL REMAIN IN PLACE OVER THE
CAROLINAS THROUGH THE WEEKEND...THEN GRADUALLY WEAKEN EARLY NEXT
WEEK. A STRONG UPPER TROUGH DEVELOPING OVER THE MISSISSIPPI VALLEY
WILL BRING TROPICAL MOISTURE OVER THE HIGH PRESSURE WEDGE TODAY AND
OVER THE WEEKEND...BRINGING WIDESPREAD SHOWERS TO THE AREA. DRIER
AND WARMER WEATHER IS EXPECTED TO RETURN BY THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 530 AM...RAIN RATES WITHIN BLOSSOMING AREA OF PRECIP IS A BIT
SURPRISING AS IT ENTERS OUR SRN COUNTIES...WITH POCKETS OF 1-2"/HR
INSTANTANEOUS RATES ON DUAL POL. THE LATEST MESOSCALE GUIDANCE...6Z
NAM...AND THE RAP ALL AGREE ON THIS PRECIP SHIELD EXPANDING AND
STREAKING NEWD ACRS ZONES ALONG AND SOUTH OF I-85 THIS MORNING. I
HAVE BUMPED POPS UP TO CATEGORICAL...AND TWEAKED THE QPF UP WHERE
THIS RAIN SHIELD GOES. TRENDS ALSO SUGGEST THAT THE I-40 CORRIDOR
WILL HAVE A DRIER MORNING THAN FCST...SO I CUT BACK POP THERE.
OTHERWISE...FCST ON TRACK.
AS OF 300 AM...A POTENT LOBE OF VORTICITY WILL ROUND THE BASE OF AN
UPR LONGWAVE TROF AXIS INVOF THE MID SOUTH EARLY THIS MORNING...THEN
CROSS THE TN VLY TO OUR CWFA THIS AFTN/EVE. THE WAVE WILL PROVIDE
MID-UPR FORCING WHICH WILL BE COUPLED WITH INCREASING LLVL LIFT
ALONG A STALLED FRONTAL BNDRY DRAPED ACRS THE SOUTHEAST STATES. A
WEAK WAVE IS PROGGED TO FORM ON A 850 MB FRONTAL ZONE INVOF
AL...INCREASING THE LLVL S/SELY FLOW ATOP A COLD AIR DAMMING WEDGE.
MODELS ARE IN DECENT AGREEMENT ON THIS SETUP...BUT FOR SOME REASON
STILL DIFFER GREATLY ON THE EXACT PLACEMENT/TIMING/MAGNITUDE OF QPF
THRU TONIGHT (AND THRU THE WEEKEND). THE NAM CONTINUES TO BE AN
OUTLIER ON A BULLSEYE OF 2-2.5" ACRS THE UPSTATE AND NE GA BY 00Z
THIS EVENING. THE NAM CONTINUES THE HIGH QPF RESPONSE INTO THE NC
PIEDMONT/FOOTHILLS TONIGHT. THE OTHER OP GUIDANCE IS A LTL MORE IN
LINE WITH GFS...HAVING LOWER MAGNITUDE...AND KEEPING THE HEAVIEST
RAIN TO OUR SOUTHEAST CLOSER TO THE SFC FRONT. I THINK THIS MAKES
SENSE...AS THE BEST PWATS/MOISTURE FLUX AND UPR DIVERGENCE WILL BE
THERE.
SO THE FCST FOR TODAY IS FOR RAIN/SHWRS TO SPREAD IN FROM THE
SOUTH...WITH GREATEST COVERAGE REMAINING ACRS ALONG AND SOUTH OF
I-85. THE RAIN AND CLOUDS SHUD LOCK IN UNSEASONABLY COOL TEMPS FOR
THE DAY...AS WEDGE BECOMES DIABATICALLY ENHANCED. A CONSENSUS BLEND
RESULTS IN MAX TEMPS 15-20 DEG BELOW NORMAL. TEMPS MAY STRUGGLE TO
REACH 70 ACRS PORTIONS OF THE UPSTATE AND SRN NC PIEDMONT...IF RAIN
IS HEAVIER AND/OR MORE PERSISTENT THAN EXPECTED.
TONIGHT...TIMING DIFFERENCES ALREADY MAKE FOR UNCERTAINTY IN THE
HOURLY POP TRENDS. IT SEEMS THERE MAY BE A RELATIVE LULL IN ACTIVITY
THIS EVENING...AS ONE WAVE PASSES BY. HOWEVER...THE UPR TROF WILL
CONTINUE TO AMPLIFY...WITH ANOTHER ROUND OF STRONGER QG FORCING AND
BETTER ISENT LIFT DEVELOPING OVERNIGHT. HAVE POPS RAMPING BACK UP TO
CATEGORICAL IN THE EAST. AGAIN...QPF IS EXPECTED TO BE SOAKING...BUT
NOT EXCESSIVE. I WENT CLOSE TO WPC FOR ALL THE 6-HOURLY QPF GRIDS IN
THE NEAR TERM.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 220 AM FRIDAY...THE SHORT TERM FCST PICKS UP AT 12Z ON
SATURDAY WITH GUIDANCE IN FAIRLY GOOD AGREEMENT ON AN UPPER LOW
DEVELOPING OVER THE MID SOUTH BY EARLY SAT. THIS LOW REMAINS NEARLY
STATIONARY SAT NITE WITH A SLIGHT NORTHEASTWARD DRIFT ON SUN AND
THEN LIFTING ON SUN NIGHT AND INTO MON. AT THE SFC...THE FCST AREA
WILL REMAIN UNDER THE COOL AIR WEDGE THRU THE END OF THE PERIOD
EARLY MON. THERE ARE SOME NOTABLE DISCREPANCIES BETWEEN THE
OPERATIONAL MODELS WRT HOW QUICKLY THE WEDGE DISSIPATES WITH THE GFS
TRYING TO MAINTAIN THE FEATURE LONGER THAN THE NAM AND ECMWF.
REGARDLESS...AS WE MOVE INTO THE MEDIUM RANGE THE BERMUDA SFC HIGH
WILL REESTABLISH ITSELF AND BRING SLY LOW LVL FLOW BACK TO THE
REGION. WITH THAT SAID...POPS WILL BE HIGH OVER MOST OF THE CWFA
THRU SUN EVENING AS FAVORABLE ISENTROPIC LIFT AND HIGH PWAT VALUES
PERSIST. BY EARLY MONDAY...LIKELY POPS WILL SHIFT TO THE EAST AS THE
BEST UPPER LVL SUPPORT MOVES TOWARDS THE COAST. GUIDANCE BLEND
CONTINUES TO SUGGEST MODERATE QPF AMOUNTS AT BEST WITH MINIMAL
INSTABILITY THRU SUN. I KEPT TEMPS WELL BELOW CLIMO WITH VALUES
STEADILY RISING EACH DAY. BY MON...WE ARE BACK IN THE LOW 80S OVER
THE UPSTATE AND PIEDMONT.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 2 AM FRIDAY...THE MEDIUM RANGE FCST PICKS UP AT 12Z ON MONDAY
WITH THE UPPER LEVEL TROUGH ERODING AND SHIFTING EASTWARD. THE COOL
WEDGE WILL GRADUALLY DISSIPATE BY THE MIDDLE OF NEXT WEEK...AS A
SURFACE HIGH BUILDS IN OVER THE CWA AND AN UPPER RIDGE GRADUALLY
SLIDES EASTWARD ACROSS THE CONUS. THIS LENDS ITSELF TO A DRIER
PERIOD...WITH A RETURN TO NORMAL SUMMERTIME DIURNAL POPS FOR THE
MIDDLE AND END OF NEXT WEEK. THE DRYING TREND WILL ALLOW
TEMPERATURES TO INCREASE BACK TO THE LOW TO MID 80S BY THE MIDDLE OF
NEXT WEEK...THOUGH HIGHS WILL STILL REMAIN A FEW DEGREES BELOW
NORMAL.
&&
.AVIATION /10Z FRIDAY THROUGH TUESDAY/...
AT KCLT...AN ABOVE AVERAGE AMOUNT OF UNCERTAINTY IN THE TRENDS WITH
THIS TAF...AS MOISTURE AND LIFT ARE EXPECTED TO INCREASE ATOP A COLD
AIR DAMMING WEDGE...WITH NUMEROUS TO WIDESPREAD SHRA OR MORE OF A
STRATIFORM PRECIP SHIELD DEVELOPING ACRS THE AREA BY DAYBREAK.
DESPITE HIGH POPS...GUIDANCE IS RELATIVELY OPTIMISTIC...WITH
GENERALLY VFR LVL CLOUDS THRUT MOST OF THE DAY. WITH THAT
SAID...THERE WILL BE A GRADIENT IN THE CIGS FROM SE TO NW...AND KCLT
MAY LEVEL OFF IN THE MVFR RANGE. BUT GOING WITH A CONSENSUS OF THE
GUIDANCE...I HAVE VFR THRU THE AFTN. SHRA COVERAGE WILL PROBABLY BE
GREATEST DURING THE MIDDAY HOURS...THEN PERHAPS A RELATIVE LULL IN
THE EVENING BEFORE ANOTHER ROUND TONIGHT. WINDS WILL STAY NELY THRU
THE PERIOD...GENERALLY 5-10 KTS.
ELSEWHERE...THE AREA IS STARTING OUT WITH INCREASING MID CLOUDS
(8-10 KFT)...BUT A LOWER VFR DECK SHUD DEVELOP AND SHRA SHUD BREAK
OUT...ESP ACRS THE UPSTATE AND ACRS THE NC MTNS BY DAYBREAK. CIGS
WILL LIKELY DROP TO MVFR ACRS THE LWR PIEDMONT...WITH KAND THE MOST
LIKELY TO STAY AT THAT LEVEL. MORE UNCERTAIN FOR KGSP/KGMU. KHKY IS
EXPECTED TO STAY VFR UNTIL THIS EVENING. KAVL ALSO IS A LOW
CONFIDENCE FCST...AND MAY BE IN AND OUT OF MVFR THRUT THE DAY DUE TO
CIGS. GUIDANCE IN BETTER AGREEMENT ON LOWER CIGS AND SOME VSBY
RESTRICTIONS AS ANOTHER ROUND OF SHRA COMES THRU TONIGHT.
OUTLOOK...A STATIONARY FRONT IS EXPECTED TO REMAIN SOUTH AND EAST OF
THE FORECAST AREA THROUGH THE WEEKEND...KEEPING THE AREA IN A COOL
MOIST WEDGE OF HIGH PRES. RESTRICTIVE CIGS AND VSBYS WILL LIKELY
PERSIST ACRS THE REGION THRU AT LEAST SUNDAY...THEN SOME IMPROVEMENT
TO MOSTLY VFR EXPECTED EARLY NEXT WEEK...AS THE WEDGE ERODES.
CONFIDENCE TABLE...
09-15Z 15-21Z 21-03Z 03-09Z
KCLT HIGH 95% HIGH 85% HIGH 84% HIGH 90%
KGSP HIGH 94% HIGH 84% HIGH 84% HIGH 97%
KAVL HIGH 84% MED 69% HIGH 93% HIGH 83%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 87%
KGMU HIGH 100% HIGH 87% HIGH 84% HIGH 100%
KAND HIGH 81% HIGH 80% HIGH 90% HIGH 97%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.CLIMATE...
RECORD LOW MAX TEMPERATURES THIS WEEKEND...
AUG 16 AUG 17 AUG 18
AVL...62 1964 72 1986 70 1905
CLT...64 1964 71 1992 72 1894
GSP...64 1964 71 1971 71 1957
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JPT
NEAR TERM...ARK
SHORT TERM...JPT
LONG TERM...JPT
AVIATION...ARK
CLIMATE...
AREA FORECAST DISCUSSION
NWS AMARILLO TX
1149 PM CDT THU AUG 15 2013
.AVIATION...DISCUSSION FOR 06Z TAFS
VFR CONDITIONS SHOULD PREVAIL WITH THE ONE CAVEAT BEING THE POTENTIAL
FOR SOME BR OR MAYBE A FEW LOW CLOUDS AT THE TAF SITES BTW 10-15Z
FRI MORNING. CONFIDENCE IS STILL TOO LOW TO INCLUDE ANY RESTRICTIONS
AS PREVAILING OR TEMPO...BUT AMENDMENTS COULD BE NEEDED. THERE COULD
BE A STRAY THUNDERSTORM FRI AFTERNOON/EVENING...BUT AGAIN CONFIDENCE
IS TOO LOW FOR ANY MENTION IN THE TAFS. WINDS WILL BE LIGHT AND
SOMEWHAT VARIABLE...BUT GENERALLY CONTAINING A SRLY OR ERLY
COMPONENT.
TAFS WILL BE OUT AT 0520Z.
SIMPSON
&&
.PREV DISCUSSION... /ISSUED 945 PM CDT THU AUG 15 2013/
UPDATE...
SEVERE THREAT CONTINUES TO DIMINISH AS IT APPEARS THAT MOST OF THE
CONVECTIVE ACTIVITY WILL REMAIN EAST OF THE PANHANDLES. LOW LEVEL
JET...AND ASSOCIATED INCREASE IN CONVECTIVE ACTIVITY HAS YET TO
MATERIALIZE...THUS HAVE CANCELED THE REMAINDER OF THE WATCH. HAVE
ALSO DECREASED POPS ACROSS THE PANHANDLES TO 20 TO 30 PERCENT.
JOHNSON
PREV DISCUSSION... /ISSUED 814 PM CDT THU AUG 15 2013/
UPDATE...
WINDOW OF RISK OF SEVERE WEATHER IS DIMINISHING...EXCEPT IN THE
EASTERN OK AND NE TX PANHANDLE WHICH MAY YET SEE STORMS DEVELOP IN
RESPONSE TO A DEVELOPING WEAK LOW LEVEL JET. THUS...WILL KEEP THE
WATCH GOING IN BEAVER...LIPSCOMB...OCHILTREE...AND HEMPHILL
COUNTIES...BUT HAVE CANCELED THE WATCH FOR THE REMAINDER OF THE TX
PANHANDLE.
JOHNSON
PREV DISCUSSION... /ISSUED 710 PM CDT THU AUG 15 2013/
AVIATION...DISCUSSION FOR 00Z TAFS
MAINLY VFR TAFS SHOULD PREVAIL THOUGH THERE ARE A FEW POTENTIALLY
AMENDABLE FEATURES OF NOTE. FIRST...SCT SHOWERS AND STORMS COULD
AFFECT ANY OF THE 3 TAF SITES THIS EVENING INTO POSSIBLY THE FIRST
FEW HOURS OF FRIDAY MORNING. HOWEVER...CONFIDENCE IS NOT HIGH ENOUGH
TO INCLUDE ANY MENTION AT THIS TIME. SECOND...A FEW LOW CLOUDS AND/OR
REDUCED VISIBILITIES WILL BE POSSIBLE AT ANY OF THE SITES FROM
16/10Z-16/15Z. WINDS WILL GENERALLY BE LIGHT THROUGH THE PERIOD
OUTSIDE OF ANY THUNDERSTORMS.
SIMPSON
PREV DISCUSSION... /ISSUED 326 PM CDT THU AUG 15 2013/
DISCUSSION...
LITTLE OR NO CHANGES TO THE PREVIOUS GRIDS AND FORECAST AS THE
WEATHER PATTERN DOES NOT CHANGE MUCH. UPPER HIGH OVER THE FOUR
CORNERS AND SOUTHWESTERN STATES THROUGH THE WEEKEND WILL MAINTAIN A
NORTHWESTERLY UPPER FLOW TONIGHT...TRANSITIONING TO NORTHERLY BY
FRIDAY NIGHT AND SATURDAY. LOOKING AT THE TTU-WRF...NAM...GFS...AND
ECMWF...BETTER ORGANIZED CONVECTION COULD POSSIBLY HOLD OFF UNTIL
AROUND 00Z FRIDAY OR LATER. THE LATEST HRRR DEVELOPS CONVECTION
ACROSS THE NORTHWEST SECTIONS OF THE FORECAST AREA BY 20Z TODAY WHICH
THEN MOVES SOUTHEAST ACROSS THE WESTERN AND CENTRAL TEXAS PANHANDLE
AROUND 22Z TODAY TO AROUND 00Z TO 02Z FRIDAY. SINCE NOT MUCH
DEVELOPING AS OF 20Z TODAY ACROSS THE PANHANDLES...THINKING THAT THE
HRRR MAY BE THE ODD MODEL OUT. CONVECTION CURRENTLY OVER OKLAHOMA AND
EAST CENTRAL NEW MEXICO MOVING SOUTH AND SOUTHEAST. WILL CONTINUE TO
MONITOR TRENDS...BUT WITH CAPES FORECAST TO BE IN THE 1500 TO 2500
J/KG RANGE AND SURFACE DEW POINTS IN THE 60S...CANNOT RULE OUT
CONVECTION DEVELOPING PRIOR TO 00Z FRIDAY.
AS THE UPPER HIGH BROADENS OVER THE SOUTHWESTERN STATES OVER THE
WEEKEND...THE UPPER FLOW TRANSITIONS TO NORTHERLY AND EVEN
NORTHEASTERLY BRINGING A GRADUAL END TO THE CONVECTION BY SUNDAY.
WARMER AND DRIER CONDITIONS SUNDAY THROUGH NEXT WEDNESDAY WITH HIGHS
CLIMBING BACK UP INTO THE 90S.
SCHNEIDER
FIRE WEATHER...
AN UPPER RIDGE ACROSS THE FOUR CORNERS REGION AND THE SOUTHWESTERN
STATES WILL MAINTAIN A NORTHWESTERLY TO NORTHERLY UPPER FLOW ACROSS
THE PANHANDLES THROUGH THE WEEKEND. SHOWERS AND THUNDERSTORMS WILL
DEVELOP ACROSS SOUTHEASTERN AND EASTERN COLORADO AND WESTERN AND
SOUTHWESTERN KANSAS LATER TODAY AND TONIGHT AND WILL MOVE SOUTHEAST
ACROSS THE PANHANDLES. NO ELEVATED OR CRITICAL FIRE WEATHER
CONDITIONS ARE EXPECTED THROUGH THE MIDDLE OF NEXT WEEK AS MINIMUM
AFTERNOON RELATIVE HUMIDITIES REMAIN AT OR ABOVE 20 PERCENT THROUGH
THE MIDDLE OF NEXT WEEK.
SCHNEIDER
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
09/16
AREA FORECAST DISCUSSION
NWS MIAMI FL
1052 AM EDT FRI AUG 16 2013
.UPDATE...
GENERALLY EAST TO EAST-SOUTHEASTERLY WINDS SHOULD PREVAIL ACROSS
THE AREA THROUGH THE AFTERNOON WITH THE EXCEPTION OF THE GULF
COAST WHERE A GULF BREEZE SHOULD DEVELOP LATER THIS AFTERNOON.
LATEST HRRR KEEPS MOST OF THE AFTERNOON SHOWERS AND THUNDERSTORMS
ACROSS THE INTERIOR. TWEAKED POPS FOR THE LATE MORNING AND EARLY
AFTERNOON HOURS...OTHERWISE ONGOING FORECAST IS ON TRACK.
&&
.PREV DISCUSSION... /ISSUED 721 AM EDT FRI AUG 16 2013/
AVIATION...
DEEP LAYERED MOISTURE CONTINUES TO LINGER ACROSS THE REGION.
ALTHOUGH THERE IS MID TO UPPER LEVEL CLOUDINESS ACROSS THE
REGION...THERE SHOULD BE SUFFICIENT CLEARING FOR DAY TIME HEATING TO
INITIATE CONVECTION ALONG WITH CONVECTION ASSOCIATED WITH THE EAST
AND WEST COAST SEA BREEZES. THE LOW LEVEL WIND PROFILE COULD BE
FAVORABLE FOR CONVECTION ALONG THE EAST COAST. FOR THE EAST COAST
TAF SITES VCTS WAS ASSIGNED IN THE 17Z TO 18Z TIME FRAME AND 17Z FOR
TERMINAL KAPF. THERE COULD BE SUB-VFR CONDITIONS AND BRIEF PERIODS
OF IFR CONDITIONS WITH THE OCCURRENCE OF SHOWERS/THUNDERSTORMS.
PREV DISCUSSION... /ISSUED 400 AM EDT FRI AUG 16 2013/
SYNOPSIS...
A STATIONARY FRONT WILL REMAIN OVER THE FLORIDA PANHANDLE THROUGH
THE WEEKEND. HIGH PRESSURE BUILDS IN EARLY NEXT WEEK. SCATTERED
AFTERNOON AND EVENING THUNDERSTORMS ARE EXPECTED TODAY THROUGH
MUCH OF NEXT WEEK...WITH GREATEST COVERAGE OVER THE INTERIOR.
SHORT TERM /TODAY THROUGH SUNDAY/...
TWO CLUSTERED OF THUNDERSTORMS BEING MONITORED EARLY THIS
MORNING...OTHERWISE SOUTH FLORIDA HAS REMAINED DRY OVERNIGHT. ONE
IS IMPACTED WATERS OFFSHORE PALM BEACH COUNTY...AND THIS ACTIVITY
IS MOVING NORTHEAST OUT OF THE CWA WHILE WEAKENING. SECOND IS
IMPRESSIVE CONVECTIVE COMPLEX JUST WEST OF GULF WATERS. THESE
FEATURE IS DEPICTED BY MESO-SCALE AND REGIONAL GUIDANCE TO
CONTINUE NORTHWARD AND NOT IMPACT OUR WATERS...BUT THERE IS THE
RISK THAT OUTFLOW FROM IT COULD INITIATE CONVECTION CLOSER TO THE
GULF COAST THIS MORNING. POPS RAISED A BIT ABOVE MODEL CONSENSUS
IN THIS AREA ACCORDINGLY.
WEATHER PATTERN IN PLACE OVER SOUTH FLORIDA THIS MORNING WILL
CHANGE LITTLE THROUGH SUNDAY. PENINSULA RESIDES ON WESTERN
PERIPHERY OF BERMUDA RIDGE...CAUSING SOUTHEASTERLY FLOW AND
MOISTURE ADVECTION FROM THE CARIBBEAN. THIS MOISTURE IS BEING
PULLED INTO AN AREA OF DISTURBED WEATHER NEAR THE YUCATAN
PENINSULA AND ALSO NORTHWARD THROUGH THE PENINSULA TO A STATIONARY
FRONT OVER THE FLORIDA PANHANDLE. OVERALL...CONVECTION WILL
CONCENTRATE NEAR THESE TO CONVERGENCE FEATURES...WITH ONLY
SCATTERED DISORGANIZED CONVECTION EXPECTED OVER SOUTH FLORIDA.
ANTICYCLONIC FLOW CENTERED NEAR SOUTHEAST FLORIDA COAST IS EVIDENT
ON REGIONAL RADAR MOSAIC AND IR SATELLITE LOOPS...THUS AT LEAST
SUBSIDENCE LITTLE OCCUR. THIS SHOULD SUPPRESS CONVECTION SOME
TODAY...ESPECIALLY EASTERN/SOUTHERN ZONES. HIGH CHANCE POPS
CONFINED TO NORTHERN INTERIOR. SIMILAR CONVECTIVE COVERAGE IS
EXPECTED SATURDAY AND SUNDAY...WITH NEAR NORMAL TEMPERATURES.
PWATS REMAIN HIGHER THAN NORMAL...JUST ABOVE 2 INCHES...SO HIGH
RAINFALL RATES ARE LIKELY IN THUNDERSTORMS TODAY. THUS...LOCALLY
HEAVY RAINFALL IS POSSIBLE...THOUGH EXPECTED COVERAGE DOESNT
WARNING HWO HIGHLIGHT.
LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
FRONT/TROUGH OVER NORTHERN FLORIDA DIMINISHES EARLY NEXT
WEEK...AND DEEP-LYR RIDGE BECOMES MORE DOMINANT IN SOUTH FLORIDA.
FLOW WILL BECOME MORE EASTERLY...FOCUSING DIURNAL CONVECTION
CLOSER TO THE GULF COAST. ECMWF/GFS FORECAST FAIRLY DRY AIR MASS
ADVECTING INTO THE REGION MONDAY/TUESDAY...SO POPS REDUCES
SLIGHTLY THESE DAYS. OTHERWISE...TEMPERATURES ARE EXPECTED TO
REMAIN AVERAGE FOR LATE AUGUST WITH NEAR/JUST BELOW
CLIMATOLOGICAL NORMAL POPS.
MARINE...
MODEST ONSHORE FLOW TODAY AND FORECAST SOUNDINGS SUGGEST LOW-LEVELS
ARE SOMEWHAT FAVORABLE FOR WATERSPOUTS...SO THESE WILL BE
MENTIONED IN HWO. ISOLATED TO SCATTERED THUNDERSTORM COVERAGE IS
EXPECTED THROUGH THE WEEKEND. HIGH PRESSURE CENTERED NORTHEAST OF
FLORIDA WILL AIDE IN SOUTHEASTERLY SURFACE FLOW FOR THE NEXT
SEVERAL DAYS. SPEEDS SHOULD REMAIN AOB 15 KTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 90 78 89 77 / 50 30 20 20
FORT LAUDERDALE 89 80 90 79 / 40 20 20 20
MIAMI 90 79 91 78 / 40 20 20 20
NAPLES 91 77 91 77 / 40 20 40 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...10/CD
AVIATION/RADAR...13/SI
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1036 AM EDT Fri Aug 16 2013
...Forecast Update...
Issued at 1035 AM EDT Fri Aug 16 2013
Did a very minor update to the grids. Basically adjust T/Td grids
over the next few hours and adjust the clouds and PoPs slightly.
Have a bit of moisture convergence down across south-central KY this
morning which has resulted in some scattered showers. Expect this
to continue through the morning and afternoon hours with the best
coverage remaining across southern KY...and lesser chances as one
heads up to the Ohio River. Afternoon highs in the upper 70s to
around 80 still look attainable.
.SHORT TERM (Now through Saturday)...
Issued at 305 AM EDT Fri Aug 16 2013
The main challenge for today will be precipitation chances over
south central KY. Weak convection formed Thurs due to forcing of an
upper level trough and sfc convergence along an inverted trough over
central TN. A line of showers and isld t-storms resulted Thurs
afternoon/evening and has been slowly dissipating and drifting
northward during the early morning hours. Left over sprinkles may
drift into our south central KY counties this morning around and
just after sunrise. A better chance of rain looks to arrive this
afternoon for south central KY if the inverted sfc trough can drift
far enough northward as the 0Z NAM and 3Z RAP suggest it will.
Expect weakly forced showers and isld t-storms to re-fire along the
boundary by mid to late afternoon and again weaken and diminish
after sunset. Although did increase POPs to 30% along the KY/TN
border, there is still some doubt that the boundary will not make it
this far north so will need to monitor closely today. Went a few
degrees cooler than MOS guidance for high temps and MOS guidance was
a few degrees too warm for Thurs highs. This puts the area in the
upper 70s to around 80 for highs this afternoon.
Tonight expect showers/storms to diminish early over south central
KY and become more focused to our west and south overnight as an
upper level wave drops down into the broad Midwest trough forming a
closed low over the mid Mississippi River Valley by Sat afternoon.
It appears that this feature may help pull the inverted sfc trough
back northward over central KY for Sat providing a better focus for
showers/t-storms. Although wind fields and overall forcing still
look meager, perhaps better overall coverage of convection can be
achieved over central KY Sat afternoon. Any storms that develop
today or Sat should not pose a severe weather threat and would be
brief/weak in nature.
Temperatures tonight should fall into the upper 50s and lower 60s
for lows. Highs Saturday afternoon will warm into the upper 70s and
lower 80s with the warmer spots located over southern Indiana which
only has a 20% chance of rain.
.LONG TERM (Saturday Night through Thursday)...
Issued at 300 AM EDT FRI Aug 16 2013
The extended forecast, starting late Saturday, will feature a
wholesale change in the configuration of the jet stream. The polar
jet, which has for several weeks now been locked in a cyclonic flow
around the Great Lakes, will retreat north into a zonal flow along
or just north of the Canadian Border. This pattern is common in
July, during high summer, and will allow a substantial late summer
warmup for the upper Midwest and the Great Lakes.
As this jet lifts north however, a digging shortwave now moving
south across Kansas will help to elongate a residual trough over the
Lower Ohio Valley. Indeed, both the NAM and the GFS closes off this
trough and creates a shallow cutoff low over the Missouri Bootheel
late Saturday. This feature will lift northeast and become absorbed
into the westerlies over Ohio by late Monday.
A tropical disturbance, now over the Yucatan Peninsula, is forecast
to slowly move northwest and may develop in to a tropical storm early
next week, Regardless of the eventual path of this feature, rich
Gulf moisture will stream northeast out of the western Gulf into the
eastern Tennessee Valley and the southern Appalachians from Sunday
into at least Tuesday of next week.
On Sunday and Monday, central Kentucky will lie in a transition
region between mostly clear skies and subsidence across northern
Indiana and the northwest fringes of an increasingly humid airmass
developing over the southern Appalachians. Weak to moderate
instability both Sunday and Monday afternoon will lead to isolated
to scattered showers and thunderstorms, especially along and south
of the Bluegrass Parkway. Think that coverage may be best Sunday
afternoon, aided by the presence of a weak 850mb circulation over
central Kentucky and a possible inverted trough extending northwards
across the Tennessee Valley. Any convection that does develop Sunday
or Monday will be diurnally driven, dissipating in the evening
hours.
Winds early next week will stay quite light. Temperatures, moderated
by possible cloudiness and the continued presence of troughing, will
remain below normal, with highs in the lower 80s by day and the mid
60s at night.
Heights begin to rise over the Lower Ohio Valley Tuesday as the last
vestiges of the eastern trough exits. Weak subsidence associated
with a slowly eastward propagating 500mb ridge over the southern plains will
most likely keep Tuesday through Thursday dry, as is shown in the
preferred ECMWF. We will experience typical late summer weather with
very light winds and pressure gradients, coupled with moderate
humidities and temperatures that, by Thursday afternoon may warm
into the upper 80s to around 90.
&&
.AVIATION (12Z TAF Update)...
Issued at 645 AM EDT Fri Aug 16 2013
VFR conditions are expected for this TAF period. An inverted sfc
trough and an upper level trough are expected to spark weak
convection near BWG this afternoon. Can`t rule out a sprinkle or
two this morning, but will hold off on a VCSH mention until better
instability/convergence organize this afternoon. A rumble of
thunder is also possible near BWG this afternoon, but chances are
too slim to mention in the TAFs at this point. Winds will continue
out of the NE at all terminals through the TAF period with max winds
between 5-7 kts this afternoon.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........MJ
Short Term.....AMS
Long Term......JSD
Aviation.......AMS
AREA FORECAST DISCUSSION
NWS JACKSON KY
1029 AM EDT FRI AUG 16 2013
.UPDATE...
ISSUED AT 1028 AM EDT FRI AUG 16 2013
A FEW SHOWERS HAVE DEVELOPED OVER SOUTH CENTRAL KY WEST OF OUR
FORECAST AREA AND OVER CENTRAL TN. THE 12Z NAM AND HRRR CONTINUE TO
POINT TOWARDS THE POSSIBILITY OF SHOWERS OVER THE SOUTHERN PART OF
THE FORECAST AREA THIS AFTERNOON...IN GOOD AGREEMENT WITH INHERITED
FORECAST. WILL CONTINUE WITH SAME AREA FOR SHOWER POSSIBILITY THIS
AFTERNOON. EXTENSIVE CLOUD COVER OVER TN HAS WORKED INTO THE SW PART
OF THE FORECAST AREA...AND HAVE MADE ADJUSTMENTS TO SKY COVER GRIDS.
THE CLOUDS WILL INHIBIT CONVECTIVE DEVELOPMENT...AND WILL CHANGE
SCATTERED SHOWERS AND THUNDERSTORMS TO SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS. NDFD AND ASSOCIATED PRODUCTS...INCLUDING ZFP...HAVE
BEEN UPDATED.
UPDATE ISSUED AT 723 AM EDT FRI AUG 16 2013
UPDATED THE FORECAST TO BETTER REFLECT CURRENT CONDITIONS AND MODEL
TRENDS. ONLY HAD TO MAKE MINOR TWEAKS TO THE TEMPERATURES AND DEW
POINTS. THE REST OF THE FORECAST IS ON TRACK.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 225 AM EDT FRI AUG 16 2013
THIS HAS BEEN AN UNUSUAL SUMMER AS IT HAS BE DOMINATED BY A UPPER LOW
OVER THE EASTERN PORTION OF THE US AND THE MODELS ARE ONCE AGAIN
BUILDING ANOTHER UPPER LOW IN OVER SOUTHERN ILLINOIS BY THIS EVENING.
WITH THIS TYPE OF PATTERN...THE POSITION OF THE UPPER LOW WILL BE
CRUCIAL AND WILL MAKE A BIG DIFFERENCE IN FORECAST. THE FORECAST IS
ALSO DIFFICULT DUE TO THE LACK OF ANY STRONG ORGANIZED SYSTEMS. THE
WEATHER WILL TEND TO BE DIURNALLY DRIVEN WITH THE BEST CHANCE FOR
CONVECTION BEING INTO THE AFTERNOON AND EARLY EVENING. WILL HAVE TO
WATCH FOR WEAK DISTURBANCES THAT WILL BE ROTATING AROUND THE LOW AND
WILL BE ABLE TO FOCUS SOME ENHANCED ACTIVITY. AT THIS POINT IN
TIME...CONFIDENCE IS LOW THAT THE MODELS WILL HAVE A GOOD HANDLE ON
THIS YET. FOR TODAY...KEPT THE PRECIPITATION MOSTLY WEST OF I 75 AS
ONLY A PORTION OF THE SYSTEM WILL BE ABLE TO INFLUENCE THE AREA.
THERE IS A MARKED DIFFERENCE IN THE NAM BUFFER SOUNDING FOR LONDON AND
JACKSON. AT JACKSON...THERE IS A PERSISTENT CAP IN PLACE THAT SHOULD
BE ABLE TO SUPPRESS THE CONVECTION THIS AFTERNOON. AT LONDON...THE
CAP DISAPPEARS AFTER 2 PM. FOR TEMPERATURES...WENT WITH THE BLEND AS
THERE IS ACTUALLY QUITE A BIT OF SPREAD BETWEEN THE VARIOUS MODELS.
WHEN THIS OCCURS AND ONE OF THE SOLUTIONS DOES NOT STAND OUT...LIKE
TO GO WITH THE BLEND.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 300 AM EDT FRI AUG 16 2013
THE MODELS WERE IN DECENT AGREEMENT WITH THE OVERALL LARGE SCALE
WEATHER PATTERN IN THE EXTENDED. A PASSING LARGE SCALE UPPER TROUGH
IS EXPECTED TO COMBINE WITH LOW LEVEL MOIST FLOW OFF THE SOUTHWESTERN
ATLANTIC. SOUTHEASTERLY FLOW AROUND THE WESTERN PERIPHERY OF THE
BERMUDA HIGH WILL PROVIDE THE WARM MOIST AIR TO THE REGION. SCATTERED
SHOWERS AND STORMS ARE PROGGED TO FORM MAINLY DURING THE AFTERNOON
AND EVENING HOURS ACROSS CENTRAL AND EASTERN KENTUCKY DURING PEAK
HEATING. THE ACTIVITY IS EXPECTED TO TAPER OFF AFTER SUNSET EACH
DAY...WITH DRY OVERNIGHT PERIODS AND MOSTLY DRY EARLY MORNING PERIODS.
HIGH TEMPERATURES THE FIRST FEW DAYS OF THE PERIOD SHOULD BE COOLER
THAN NORMAL...WITH WIDESPREAD CLOUD COVER AND PRECIPITATION IN THE
FORECAST. HIGHS ON SUNDAY AND MONDAY WILL TOP OUT AROUND 80 DEGREES.
FROM WEDNESDAY ONWARD SHOULD TOP OUT AT OR ABOVE NORMAL...WITH
READINGS IN THE MID TO UPPER 80S EACH DAY UNDER A SOUTHERLY FLOW
REGIME AND PARTLY CLOUDY SKIES. OVERNIGHT LOWS WILL DROP INTO THE
60S...WHICH IS NORMAL FOR THIS TIME OF YEAR.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 723 AM EDT FRI AUG 16 2013
HIGH PRESSURE OVER THE OHIO VALLEY WILL KEEP MOSTLY VFR CONDITIONS
ACROSS THE FORECAST AREA THROUGH SATURDAY. THERE WAS NOT ANY FOG AT
THE TAF SITES THIS MORNING AND ALTHOUGH WE DO EXPECT SOME MVFR
VISIBILITY IN FOG AROUND DAYBREAK SATURDAY IN MANY OF OUR VALLEY
LOCATIONS THE FLOW FROM THE NORTHEAST IS NOT CONDUCIVE FOR FOG OR
FOG ADVECTION AT OUR TAF SITES. THIS AFTERNOON...THERE MAY BE SOME
CONVECTION WEST OF A LINE FROM PULASKI TO BELL COUNTIES. PUT SOME
VCSH AT SME...BUT NOT AT LONDON AS THE SYSTEM SHOULD STAY TO THE
WEST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...JJ
LONG TERM...AR
AVIATION...JJ
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
645 AM EDT Fri Aug 16 2013
...Updated Aviation Discussion...
.SHORT TERM (Now through Saturday)...
Issued at 305 AM EDT Fri Aug 16 2013
The main challenge for today will be precipitation chances over
south central KY. Weak convection formed Thurs due to forcing of an
upper level trough and sfc convergence along an inverted trough over
central TN. A line of showers and isld t-storms resulted Thurs
afternoon/evening and has been slowly dissipating and drifting
northward during the early morning hours. Left over sprinkles may
drift into our south central KY counties this morning around and
just after sunrise. A better chance of rain looks to arrive this
afternoon for south central KY if the inverted sfc trough can drift
far enough northward as the 0Z NAM and 3Z RAP suggest it will.
Expect weakly forced showers and isld t-storms to re-fire along the
boundary by mid to late afternoon and again weaken and diminish
after sunset. Although did increase POPs to 30% along the KY/TN
border, there is still some doubt that the boundary will not make it
this far north so will need to monitor closely today. Went a few
degrees cooler than MOS guidance for high temps and MOS guidance was
a few degrees too warm for Thurs highs. This puts the area in the
upper 70s to around 80 for highs this afternoon.
Tonight expect showers/storms to diminish early over south central
KY and become more focused to our west and south overnight as an
upper level wave drops down into the broad Midwest trough forming a
closed low over the mid Mississippi River Valley by Sat afternoon.
It appears that this feature may help pull the inverted sfc trough
back northward over central KY for Sat providing a better focus for
showers/t-storms. Although wind fields and overall forcing still
look meager, perhaps better overall coverage of convection can be
achieved over central KY Sat afternoon. Any storms that develop
today or Sat should not pose a severe weather threat and would be
brief/weak in nature.
Temperatures tonight should fall into the upper 50s and lower 60s
for lows. Highs Saturday afternoon will warm into the upper 70s and
lower 80s with the warmer spots located over southern Indiana which
only has a 20% chance of rain.
.LONG TERM (Saturday Night through Thursday)...
Issued at 300 AM EDT FRI Aug 16 2013
The extended forecast, starting late Saturday, will feature a
wholesale change in the configuration of the jet stream. The polar
jet, which has for several weeks now been locked in a cyclonic flow
around the Great Lakes, will retreat north into a zonal flow along
or just north of the Canadian Border. This pattern is common in
July, during high summer, and will allow a substantial late summer
warmup for the upper Midwest and the Great Lakes.
As this jet lifts north however, a digging shortwave now moving
south across Kansas will help to elongate a residual trough over the
Lower Ohio Valley. Indeed, both the NAM and the GFS closes off this
trough and creates a shallow cutoff low over the Missouri Bootheel
late Saturday. This feature will lift northeast and become absorbed
into the westerlies over Ohio by late Monday.
A tropical disturbance, now over the Yucatan Peninsula, is forecast
to slowly move northwest and may develop in to a tropical storm early
next week, Regardless of the eventual path of this feature, rich
Gulf moisture will stream northeast out of the western Gulf into the
eastern Tennessee Valley and the southern Appalachians from Sunday
into at least Tuesday of next week.
On Sunday and Monday, central Kentucky will lie in a transition
region between mostly clear skies and subsidence across northern
Indiana and the northwest fringes of an increasingly humid airmass
developing over the southern Appalachians. Weak to moderate
instability both Sunday and Monday afternoon will lead to isolated
to scattered showers and thunderstorms, especially along and south
of the Bluegrass Parkway. Think that coverage may be best Sunday
afternoon, aided by the presence of a weak 850mb circulation over
central Kentucky and a possible inverted trough extending northwards
across the Tennessee Valley. Any convection that does develop Sunday
or Monday will be diurnally driven, dissipating in the evening
hours.
Winds early next week will stay quite light. Temperatures, moderated
by possible cloudiness and the continued presence of troughing, will
remain below normal, with highs in the lower 80s by day and the mid
60s at night.
Heights begin to rise over the Lower Ohio Valley Tuesday as the last
vestiges of the eastern trough exits. Weak subsidence associated
with a slowly eastward propagating 500mb ridge over the southern plains will
most likely keep Tuesday through Thursday dry, as is shown in the
preferred ECMWF. We will experience typical late summer weather with
very light winds and pressure gradients, coupled with moderate
humidities and temperatures that, by Thursday afternoon may warm
into the upper 80s to around 90.
&&
.AVIATION (12Z TAF Update)...
Issued at 645 AM EDT Fri Aug 16 2013
VFR conditions are expected for this TAF period. An inverted sfc
trough and an upper level trough are expected to spark weak
convection near BWG this afternoon. Can`t rule out a sprinkle or
two this morning, but will hold off on a VCSH mention until better
instability/convergence organize this afternoon. A rumble of
thunder is also possible near BWG this afternoon, but chances are
too slim to mention in the TAFs at this point. Winds will continue
out of the NE at all terminals through the TAF period with max winds
between 5-7 kts this afternoon.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Short Term........AMS
Long Term.........JSD
Aviation..........AMS
AREA FORECAST DISCUSSION
NWS CARIBOU ME
610 AM EDT FRI AUG 16 2013
.SYNOPSIS...
A COLD FRONT WILL BECOME STATIONARY OVER NORTH CENTRAL PORTIONS OF
THE REGION TODAY...THEN MOVE SOUTHEAST OF THE REGION TONIGHT. HIGH
PRESSURE WILL THEN BUILD ACROSS THE REGION THROUGH THE WEEKEND
INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
6 AM UPDATE: WITH PATCHY FOG ALREADY BEGINNING TO DISSIPATE THIS
HR...WE TOOK THE MENTION OF FOG OUT OF ZONE FORECAST TEXTS. ALSO...
WE UPDATED THE PRIOR NGT`S FCST LOW WITH OBSVD HRLY TEMPS AT 5-6
AM...THEN RE-INTERPOLATED THE HRLY TEMP FCST TO POSTED MID AFTN HI
TEMPS. OTHERWISE...NO CHGS WERE MADE TO THE CURRENT FCST TMG OF
CLDS...POPS AND WX GRIDS...WITH ENSM MODEL DATA FROM THE BOTH THE
SREF AND GFS AS WELL AS HRLY HRRR SIMULATED MODEL RADAR REF
SUPPORTING A VERY SIMILAR SCENARIO TO OUR FCST INTO THE ERLY EVE.
ORGNL DISC: THE CONSENSUS OF MODELS IN THE NEAR TERM CONT TO SHOW
THE PROGRESSION OF AN UPPER TROF FROM ERN QB THIS MORN ACROSS NRN
ME THIS AFTN AND INTO NB THIS EVE. MEANWHILE...A SFC COLD FRONT IS
IS EXPECTED TO STALL OVR N CNTRL PTNS OF THE FA BEFORE MOVG SE
AGAIN TONIGHT. THE COMBINATION OF THESE TWO FACTORS WILL RESULT IN
MORE GENERAL SHWR AND SCT TSTM CVRG ACROSS NRN AND CNTRL PTNS OF
THE FA THAN YSTDY...WITH LIKELY POPS JUSTIFIED BASED ON OUR FCST
OF AREAL BASIN QPF...SPCLY IN THE 2-8PM TM FRAME. THE PROGRESSION
OF SHWRS AND TSTMS TO THE ESE THIS AFTN AND ERLY EVE FROM FAR NRN
ME MIDDAY WILL BE TIED TO THE EVOLUTION OF SBCAPE DURG THIS TM
FRAME... WITH SBCAPE XPCTD TO MAXIMIZE SOMEWHERE BETWEEN 500 AND
1000J/KG OVR NE AND E CNTRL PTNS OF THE FA BY LATE AFTN. FOR THIS
REASON... ALG WITH WITH LOW FZG AND -20 DEG C LVLS...WE ADDED
ENHANCED WORDING FOR A FEW STORMS CONTAINING SMALL HAIL AND
LOCALIZED STRONG WIND GUSTS. HI TEMPS WILL ONCE AGAIN WILL BE
BELOW NORMAL FOR THIS DATE BY ABOUT 5 DEG F.
SHWRS AND TSTMS SHOULD SLOWLY DISSIPATE AND MOVE ESE OUT OF THE
FA WITH THE LOSS OF HTG AND THE PASSAGE OF THE UPPER TROF E OF THE
REGION. THIS WILL ALLOW FOR CLRG TO WORK IN FROM WRN AREAS LATE
THIS EVE TO THE REST OF THE FA LATE TNGT. ALTHOUGH WINDS WILL BE
LGT...THE LESSER WINDOW OF CLR SKIES WILL KEEP OVRNGT LOWS FROM
REACHING QUITE AS LOW AS PREVIOUSLY THOUGHT. WITH WET GROUNDS
FROM AFT/ERLY EVE RNFL HOWEVER...PATCHY FOG WILL BE POSSIBLE
LATE TNGT...WITH WEAK LLVL COOL/DRY ADVCN WORKING AGAINST THE
POTENTIAL OF MORE WIDESPREAD AND DENSE FOG ATTM...BUT THIS WILL
NEED TO BE MONITORED.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
HIGH PRESSURE WILL BRING DRY CONDITIONS AND HIGHS IN THE MID TO UPPER
70S SATURDAY AND LOW 80S ON SUNDAY. HUMIDITY WILL BE LOW THROUGH
THE WEEKEND. CLOUD COVER WILL BE MORE WIDESPREAD SATURDAY
AFTERNOON WITH CU AND STRATOCU FIELDS DUE TO H850 MOISTURE. AFTER
THESE CLOUDS DISSIPATE...LOWS SATURDAY NIGHT WILL DIP TO THE UPPER
40S TO LOW 50S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE AND WARM AIR ADVECTION WILL PRODUCE HIGHS IN LOW TO
MID 80S MONDAY. SOUTHWEST WINDS WILL INCREASE WITH GUSTS TO 20
MPH. A COLD FRONT WILL APPROACH MONDAY NIGHT. THE BIG QUESTION IS
WHETHER IT WILL MAKE IT INTO THE FORECAST AREA OR JUST REACH THE
FORECAST AREA AND STALL. THIS FRONT WILL INTRODUCE HIGH HUMIDITY
THAT WILL LINGER FOR THE REST OF THE WEEK. HAVE GONE WITH MUCH MORE
CLOUDS AND LOWER TEMPERATURES IN NORTHERN ZONES FOR TUESDAY. ALSO
ADDED A CHANCE OF SHOWERS IN THE NORTHERN ZONES. THE FRONT IS
EXPECTED TO MOVE BACK NORTH FOR WEDNESDAY WITH HIGH PRESSURE BACK
IN CONTROL AND HIGHS IN THE UPPER 70S TO LOW 80S. ANOTHER FRONT IS
EXPECTED THURSDAY WITH A SLIGHT CHANCE OF SHOWERS.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
NEAR TERM: MSLY VFR FOR OUR TAF SITES XCPT LCLY MVFR/IFR IN PATCHY
FOG ERLY THIS MORN AND LATE TNGT...BRIEFLY IN ANY DOWNPOURS WITH
ANY TSTMS OR HEAVIER SHWRS THIS AFTN INTO ERLY EVE.
SHORT TERM: VFR EXPECTED OUTSIDE OF PATCHY FOG NEAR SUNRISE SUNDAY
MORNING. MVFR CIGS ARE POSSIBLE TUESDAY NORTH OF HUL.
&&
.MARINE...
NEAR TERM: NO HDLNS ANTICIPATED WITH WV HTS OVR OUTER MZS SLOWLY
SUBSIDING BLO 3 FT AND NEAR COASTLINE WV HTS IN THE 1 TO 2 FT
RANGE. USED A BLEND OF WW3 AND SWAN NAM FOR FCST WV HTS...SMOOTHED
ALG THE IMMEDIATE COASTLINE 10X TO LOWER WV HTS WITH A MIN WV HT
OF 1 FOOT.
SHORT TERM: LIGHT WINDS AND SEAS 2 FEET OR LESS ARE EXPECTED WITH
HIGH PRESSURE IN CONTROL. WINDS MAY GUST TOWARDS 15 KTS ON MONDAY.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...VJN
SHORT TERM...MCW
LONG TERM...MCW
AVIATION...VJN/MCW
MARINE...VJN/MCW
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
924 AM EDT FRI AUG 16 2013
.UPDATE...
ISSUED AT 922 AM EDT FRI AUG 16 2013
PESKY PATCH OF MID CLOUDS/ISOLD SHRA OVER SCNTRL LK SUPERIOR LED TO
UPDATE FOR CNTRL CWA FOR THE AFTN. SPC MESOANALYSIS SHOWS SHRA ARE
IN AREA OF H7 MOISTURE CONVERGENCE AND WEAK ELEVATED CAPE. WV LOOP
SHOWS A HINT OF A WAVE AS WELL. THAT FEATURE SHOULD REMAIN IN TACT
AS IT DRIFTS ACROSS ECNTRL UPR MICHIGAN /P53 TO ERY/ THIS AFTN. THIS
WILL ALSO MATCH UP WITH PEAK HEATING. CONVECTIVE TEMPS IN THE UPR
70S TO LOWER 80S SUGGEST EVEN WITH ADDITIONAL MOISTURE AND FORCING
THAT SHRA COVERAGE WILL REMAIN MINIMAL AND LATEST RAP SOUNDINGS
INDICATE DRY AIR BLO CLOUD BASE. PUT A MENTION OF SPRINKLES IN FROM
ALGER TO LUCE COUNTIES THIS AFTN AS CU DECK EXPANDS WITH ADDITIONAL
MOISTURE. ELSEWHERE CU SHOULD STAY CAPPED AND NUDGED MAX TEMPS UP A
FEW DEGREES BASED ON 12Z RAOBS FM INL/GRB. MOST AREAS OVER INTERIOR
WEST HALF OF CWA SHOULD SEE TEMPS TOP OUT AROUND 80 DEGREES. &&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 432 AM EDT FRI AUG 16 2013
BATTLING TEMPORARY VIS RESTRICTIONS AT A FEW OF THE SITES INLAND
FROM LAKE SUPERIOR THIS MORNING...AS IWD...IMT...ESC...AND ISQ JUMP
BETWEEN AROUND 1SM AND P6SM. HAVE KEPT PATCHY FOG GOING TO COVER
THIS...WITH A COUPLE POCKETS OF AREAS OF FOG NEAR THE LAKE MI
SHORELINE THROUGH DAYBREAK.
THE SFC RIDGE WILL REMAIN OVERHEAD...WITH THE HIGH STRENGTHENING
ACROSS THE NEW ENGLAND STATES THIS AFTERNOON THROUGH TONIGHT. LOW
PRESSURE WILL CONTINUE TO NEAR FROM THE W...WITH THE FIRST SFC LOW
ACROSS SASKATCHEWAN INTO N MANITOBA THIS MORNING SHIFTING E ABOUT
500MI BY 12Z SATURDAY /TO S MANITOBA AND S CENTRAL HUDSON BAY/.
WHILE THERE WILL BE WAA WITH 850MB TEMPS RISING FROM A CWA AVG OF
12C TO 13C BY THE END OF THE DAY IT WILL BE FAIRLY WEEK...AS NOTED
BY TRANSPORT WINDS OF 10KTS OR LESS OUT OF THE W TO SW...EVEN WITH
MIXING HEIGHTS OF 6-7.8KFT.
THE SW FLOW WILL PICK UP SLIGHT OVER W LAKE SUPERIOR OVERNIGHT
/AROUND 15KTS OR LESS/...WHILE REMAINING LIGHT OVER THE LAND.
CONTINUED TO GO AT OR BELOW GUIDANCE VALUES FOR OVERNIGHT LOWS GIVEN
OUR CLEAR SKY AND LIGHT WINDS...WITH UPPER 40S EXPECTED IN THE
TRADITIONAL COOL SPOTS WELL INLAND FROM THE GREAT LAKES.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 319 AM EDT FRI AUG 16 2013
MAIN FCST CONCERNS IN THE LONG TERM ARE TEMPS AND RELATIVELY SMALL
PCPN CHCS BEGINNING LATER ON SUN WITH PASSAGE OF DISTURBANCES IN
FAST W FLOW OVER SRN CANADA. ABOVE NORMAL HGTS ASSOCIATED WITH
SPRAWLING RDG OVER THE CONUS WL BRING ABV NORMAL TEMPS TO UPR MI
THIS WEEKEND AND NEXT WEEK.
SAT THRU SUN...CWA IS FCST TO BE DOMINATED BY DRY AIRMASS/ACYC WSW
FLOW ARND HI PRES CENTERED OVER THE NE CONUS. EXPECT MOCLR SKIES AND
A SLOW WARMING TREND WITH FCST H85 TEMPS 12-14C ON SAT AND THEN
14-16C ON SUN. STEADY SW WIND SHOULD HOLD MIN TEMPS UP ON SAT NGT...
ESPECIALLY IN THE DOWNSLOPE AREAS NEAR LK SUP FM IWD THRU THE
KEWEENAW TO BARAGA AND MQT.
SUN NGT/MON...LATEST LONGER RANGE GUIDANCE IN FAIRLY GOOD AGREEMENT
SHOWING A SHRTWV EMBEDDED IN THE WLY FLOW OVER SRN CANADA DIPPING
INTO THE UPR GRT LKS AND WEAKENING THE UPR RDG A BIT. THE GFS IS THE
MOST AGGRESSIVE MODEL TO WEAKEN THE RDG/GENERATE SHRA AND TS OVER
UPR MI. WL CARRY SOME LO CHC POPS OVER MAINLY THE NRN TIER OF THE
CWA CLOSER TO THE LOWER HGTS AND STNRY FNT FCST OVER SRN ONTARIO
JUST N OF LK SUP. MORE CLDS ARE LIKELY TO HOLD TEMPS UP A BIT MORE
ON SUN NGT BUT MAY CAUSE TEMPS TO RUN A BIT COOLER ON
MON...ESPECIALLY OVER THE NRN TIER.
EXTENDED...NOT SURPRISINGLY...EXTENDED MODEL GUIDANCE BEGINS TO SHOW
SOME DISAGREEMENT ON HOW MUCH THE UPR RDG WL BUILD BACK OVER THE UPR
LKS ON TUE FOLLOWING DEPARTURE OF SHRTWV RESPONSIBLE FOR SHRA/TS
POTENTIAL ON SUN NGT/MON AND THEN WHETHER/HOW QUICKLY MORE SHRTWVS
MIGHT IMPACT THE AREA AND FURTHER DEPRESS THE HIER HGTS OVER THE UPR
LKS AND TRY TO PUSH A STRONGER COLD FNT THRU UPR MI. CONSIDERING THE
LO PREDICTABILITY OF THESE DETAILS OF ZONAL FLOW REGIME IN THE
EXTENDED DURING SUMMER...FOLLOWED MODEL CONSENSUS FCST. OVERALL...
TEMPS SHOULD RUN ABV NORMAL...ESPECIALLY IF THE MODELS SHOWING THE
MORE PERSISTENT/STRONGER UPR RDG WITH NO FROPA THRU NEXT THU ARE
CORRECT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 555 AM EDT FRI AUG 16 2013
OTHER THAN A FEW MID CLOUDS PASSING FROM TIME TO TIME...THE TAF
PERIOD WILL REMAIN FAIRLY CALM...WITH VFR CEILINGS AND VIS
ANTICIPATED. THERE IS A SMALL POTENTIAL FOR OCCASIONAL BR AGAIN AT
IWD AND TO A LESSER EXTENT SAW OVERNIGHT...BUT WILL KEEP IT OUT OF
THE FCST FOR NOW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 319 AM EDT FRI AUG 16 2013
OVERALL EXPECT WINDS LESS THAN 20 KTS THROUGH THE PERIOD AS HI
PRESSURE PERSISTS OVER THE GREAT LAKES REGION. THE ONE EXCEPTION
WILL BE SUN MORNING OVER THE NORTH CENTRAL...WHERE SW WINDS WILL
PEAK UP TO 25 KTS AHEAD OF A DISTURBANCE MOVING TOWARD THE UPPER
LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...JLA
SHORT TERM...KF
LONG TERM...KC
AVIATION...KF
MARINE...KC
AREA FORECAST DISCUSSION
NWS HASTINGS NE
555 AM CDT FRI AUG 16 2013
.UPDATE...
ISSUED AT 501 AM CDT FRI AUG 16 2013
KUEX INDICATES SHOWER AND THUNDERSTORM ACTIVITY HAS DEVELOPED OVER
PORTIONS OF CENTRAL KANSAS...JUST SOUTH OF OUR CWA. RAP ANALYSIS
DATA INDICATES A SUBTLE MID LEVEL PERTURBATION IS ADVANCING SOUTH
FROM CENTRAL NEBRASKA INTO KANSAS...WITH WATER VAPOR IMAGERY ALSO
INDICATING A SUBTLE VORT MAX MOVING INTO KANSAS. BASED ON THE
POSITION OF THE SUBTLE VORT MAX ON WATER VAPOR IMAGERY...AND THE
POSITION OF THE MID LEVEL PERTURBATION FROM RAP ANALYSIS DATA...IT
APPEARS THE MID LEVEL TROUGH AXIS IS OVER OUR CWA NOW...WITH WEAK
MID LEVEL THERMAL ADVECTION AND DPVA AHEAD OF THIS TROUGH AXIS
LIKELY PROMOTING JUST ENOUGH OMEGA FOR PRECIPITATION PRODUCTION TO
OUR SOUTH. IN ADDITION TO THE MID LEVEL PERTURBATION...A SUBTLE
SURFACE TROUGH...PERHAPS A WEAK LOW LEVEL BAROCLINIC ZONE...IS
ALSO EVIDENT EXTENDING FROM WESTERN KANSAS INTO CENTRAL AND EAST-
CENTRAL KANSAS. RAP ANALYSIS SUGGESTS WEAK ISENTROPIC UPGLIDE IN
EXISTENCE ALONG/NEAR THE 295K SURFACE ACROSS THIS BOUNDARY...WITH
THE ONGOING SHOWER AND THUNDERSTORM ACTIVITY OCCURRING ALONG THIS
AXIS OF ISENTROPIC UPGLIDE. AT THIS TIME IT APPEARS THE WEAK MID
LEVEL OMEGA AND LOW LEVEL THERMAL ADVECTION RESPONSIBLE FOR THE
ONGOING PRECIPITATION PRODUCTION SHOULD REMAIN JUST SOUTH OF OUR
CWA...ALTHOUGH NOT BY MUCH...THUS ALLOWING FOR A CONTINUED DRY
FORECAST THROUGH THIS MORNING. THAT BEING SAID...THE ONGOING
SHOWER AND THUNDERSTORM ACTIVITY WILL NEED TO BE MONITORED TO MAKE
SURE IT DOES NOT SNEAK NORTHWARD INTO EXTREME SOUTHERN PORTIONS OF
OUR CWA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 331 AM CDT FRI AUG 16 2013
OVERNIGHT MAP ANALYSIS INDICATES A LONGWAVE MID TO UPPER LEVEL
TROUGH IN EXISTENCE ACROSS THE EASTERN HALF OF THE CONUS...AND A
RIDGE OVER THE WEST. MID TO UPPER LEVEL JET ENERGY EXTENDS FROM
THE NORTHWESTERN CONUS...NORTHEAST INTO SOUTHWESTERN CANADA...THEN
SOUTHEAST ACROSS THE CENTRAL CONUS...AND FINALLY EAST AND
EVENTUALLY NORTHEAST ACROSS PORTIONS OF THE SOUTHEASTERN CONUS AND
EVENTUALLY THE EAST/NORTHEASTERN CONUS. MID TO UPPER LEVEL FLOW
OVER THE CENTRAL PLAINS REMAINS FROM THE NORTHWEST AS A RESULT BUT
IS NOT PARTICULARLY STRONG...ONLY MAXING OUT AT AROUND 45KTS NEAR
200MB PER 00Z SOUNDING DATA FROM KLBF AND KOAX. THE AFOREMENTIONED
MID LEVEL LONGWAVE RIDGE AND TROUGH CAN ALSO BE SEEN ON WATER
VAPOR IMAGERY...WITH INCREASED VALUES OF MID LEVEL MOISTURE ALSO
NOTED FLOWING ALONG THE AFOREMENTIONED JET AXIS. AT THE SURFACE A
SUBTLE TROUGH IS NOTED EXTENDING FROM WESTERN KANSAS INTO PORTIONS
OF NORTHEASTERN KANSAS. THE LOW LEVEL WIND FIELD ACROSS OUR AREA
REMAINS FROM THE EAST/NORTHEAST AS A RESULT.
GUIDANCE FROM THE NAM...OPERATIONAL GFS...EC...AND SREF-MEAN ALL
SUGGEST THE WESTERN CONUS LONGWAVE TROUGH WILL DRIFT EAST SOMEWHAT
THROUGH THE NEXT 24 HOURS. THE RESULTANT LACK IN OVERALL KINEMATIC
FORCING SUGGESTS DRY CONDITIONS SHOULD BE OBSERVED ACROSS OUR AREA
TODAY AND TONIGHT. THE ONLY OPPORTUNITY FOR MEASURABLE
PRECIPITATION MAY BE ACROSS OUR SOUTHWEST 06-12Z SATURDAY AS WEAK
LOW LEVEL THERMAL ADVECTION ALONG THE AXIS OF ~30KT 850MB JET AXIS
PROMOTES ISOLATED TO SCATTERED SHOWER AND THUNDERSTORM ACTIVITY
OVER THE CENTRAL HIGH PLAINS. THERE IS AN OUTSIDE CHANCE SOME OF
THIS ACTIVITY COULD CREEP INTO OUR FAR SOUTHWESTERN CWA BUT AT
THIS TIME CONFIDENCE IS NOT HIGH ENOUGH TO INSERT POPS INTO THE
SHORT TERM FORECAST PERIOD AND AS A RESULT...DRY CONDITIONS ARE
CURRENTLY FORECAST THROUGH 12Z SATURDAY.
ALTHOUGH CONFIDENCE WITH RESPECT TO MEASURABLE PRECIPITATION BEING
REALIZED ACROSS OUR CWA IS VERY LOW...CONFIDENCE WITH RESPECT TO
INCREASING CLOUD COVER ACROSS OUR AREA TONIGHT INTO EARLY SATURDAY
IS INCREASING. GUIDANCE FROM THE NAM AND OPERATIONAL GFS...AS WELL
AS THE MET AND MAV...SUGGEST THE AFOREMENTIONED LOW LEVEL THERMAL
ADVECTION ALONG THE AXIS OF THE LOW LEVEL JET STREAK SHOULD BE
STRONG ENOUGH TO PROVIDE ISENTROPIC UPGLIDE AND
SATURATION...PRIMARILY ALONG THE 300-305K SURFACES. GIVEN THESE
SOLUTIONS...WENT AHEAD AND INCREASED CLOUD COVER SIGNIFICANTLY
ACROSS MUCH OF OUR CWA TONIGHT INTO EARLY SATURDAY MORNING. IN
ADDITION TO THE STRATUS...NEAR-ZERO LOW LEVEL DEW POINT
DEPRESSIONS AND A LIGHT SOUTHEAST LOW LEVEL WIND FIELD COULD ALSO
PROMOTE FOG DEVELOPMENT ACROSS PORTIONS OF THE CWA TOWARDS
DAYBREAK SATURDAY. GIVEN THIS POTENTIAL...WENT AHEAD AND INSERTED
PATCHY FOG INTO THE GRIDS FOR EARLY SATURDAY MORNING.
PERSISTENT CLOUD COVER THROUGH MID TO LATE THIS MORNING...ALONG
WITH A PERSISTENT EASTERLY COMPONENT TO THE LOW LEVEL WIND
FIELD...WILL LIKELY KEEP TEMPERATURES ON THE COOL SIDE TODAY.
GUIDANCE FROM THE MET...MAV...AND ECS ALL SEEM TO HAVE A GOOD
HANDLE ON THIS AND TAKING AN EVEN-AVERAGE OF THESE THREE SETS OF
GUIDANCE PROVIDES AFTERNOON HIGHS IN THE MID 70S ACROSS THE
NORTHEASTERN TWO-THIRDS OF OUR CWA...AND CLOSER TO 80 ACROSS OUR
SOUTHWEST. LITTLE CHANGE IN THE LOW LEVEL AIRMASS AND INCREASING
CLOUD COVER...MUCH LIKE WE ARE OBSERVING THIS MORNING...SHOULD
PROVIDE SIMILAR OVERNIGHT LOW TEMPERATURES TONIGHT WHEN COMPARED
TO EARLY THIS MORNING. GIVEN THIS...WENT AHEAD WITH EARLY SATURDAY
MORNING TEMPERATURES NEAR 60 FOR MOST LOCATIONS ACROSS THE CWA.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 331 AM CDT FRI AUG 16 2013
A PATTERN CHANGE APPEARS TO BE ON THE WAY THAT WILL RESULT IN
DRIER WX AND TEMPS MORE TYPICAL OF SUMMER. THE MID-SUMMER BREAK
FOR A/C UNITS WILL END AS MULTIPLE DAYS OF 90F HEAT ARE IN THE
OFFING.
ALOFT: NOW THAT THE AK-CANADA HIGH LATITUDE BLOCKING IS FINALLY
BREAKING DOWN...THE FAIRLY HIGH AMPLITUDE ROCKIES RIDGE/ERN USA
TROF COMBO THAT HAS DOMINATED THE WX FOR THE PAST TWO WEEKS WILL
DE-AMPLIFY AS WELL. THE WESTERLIES WILL BECOME ZONAL AGAIN OVER
CANADA AND THE NRN USA. MEANWHILE...THE TROF OVER THE E PAC WILL
CLOSE OFF AND BECOME CUT-OFF...LINGERING OVER CA FOR THE NEXT
SEVERAL DAYS. THIS COMBINED WITH THE ERN USA TROF LIFTING OUT WILL
ALLOW THE SUBTROPICAL HIGH TO EXPAND ACROSS MOST OF THE CONUS. THE
WARMER TEMPS ALOFT SHOULD PUT A CAP ON PCPN POTENTIAL FOR SEVERAL
DAYS.
SFC: EXPANSIVE HIGH PRES THAT HAS BEEN PARKED OVER THE OH VALLEY
WILL GRADUALLY REPOSITION ITSELF OVER THE WRN ATLANTIC...BUT IT
WILL STILL EXTEND BACK INTO THE ERN USA. AS A SERIES OF LOWS
TRACKS ACROSS CANADA...A LEE-SIDE TROF WILL DEVELOP. THE INCREASED
PRES GRADIENT WILL RESULT IN A BIT MORE WIND THAN WE/VE SEEN FOR
THE LAST COUPLE WEEKS. THE NEXT COOL FRONTAL PASSAGE IS ADVERTISED
FOR NEXT THU AFTN-NGT.
THE 00Z EC AND GFS LOOK NOTHING ALIKE AT THE SFC AT 168 HRS /00Z
FRI/. THE GFS HAS A STRONGER SHRTWV TROF OVER THE PAC NW /H5 HGTS
40-60 M LOWER/ WHICH RESULTS IN A 997 MB LOW OVER ND VS. THE EC
1019 MB HIGH OVER LAKE WINNIPEG. THE 18Z GFS WAS MORE SUPPORTIVE
OF THE EC SOLUTION. SO THE 00Z RUN WAS NOT FACTORED INTO THIS FCST
BEYOND TUE.
THE DAILY DETAILS...
SAT: WIDESPREAD LOW STRATUS APPEARS LIKELY VIA MODEL CROSS
SECTIONS. SINCE IT/S CURRENTLY IN-PLACE AND THE FCST AREA WILL
REMAIN ON THE WRN FRINGE OF A SIZABLE POOL OF COOL AIR IN THE LOW-
LVLS...IT WILL BE HARD TO GET RID OFF UNTIL THE THERMAL TROF
RELEASES ITS GRIP WHICH WILL PROBABLY HAPPEN SUN.
SO EXPECT A CLOUDY START MOST AREAS WITH SLOW BUT GRADUAL
IMPROVEMENT. THERE WILL PROBABLY BE SOME AREAS THAT DON/T
COMPLETELY CLEAR OUT UNTIL MID-LATE AFTN. CAN FORESEE PARTS OF THE
FCST AREA NOT REACHING 80F.
SAT NGT: THE PRES GRADIENT WILL KEEP WINDS 7-15 MPH. SO DON/T
ENVISION FOG BEING A PROBLEM...BUT GIVEN THAT THE STRATUS/HIGH
LOW-LVL MSTR MAY NOT COMPLETELY MIX OUT SAT AFTN...LOW CLOUDS
SHOULD REFORM. JUST NOT SURE TO WHAT EXTENT.
SUN: THE DAY MAY START WITH STRATUS COVERING ALL OR PART OF THE
FCST AREA. FCST SOUNDINGS SUGGEST DRIER AIR WILL MIX DOWN. SO
IMPROVEMENT SHOULD BE MORE PERMANENT. SHOULD BE AN ESPECIALLY NICE
DAY FOR OUTDOOR ACTIVITIES BUT WITH S WINDS GUSTING UP TO 25 MPH.
MON-WED: SUNNY AND DRY AS WE SEE IT NOW. HIGH TEMPS WILL AVERAGE
ABOUT 5F WARMER THAN NORMAL.
THE NEXT OPPORTUNITY FOR TSTMS IS SLATED FOR THU AFTN-EVNG WITH A
COOL FRONTAL PASSAGE. WITH SUCH A WARM LOOK TO THE HGTS ALOFT...
CAPPING WILL PROBABLY LIMIT COVERAGE TO JUST AN ISOLATED TSTM OR
TWO.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 555 AM CDT FRI AUG 16 2013
IFR CONDITIONS FORECAST UNTIL 17Z...VFR CONDITIONS 17-05Z...AND
MVFR CONDITIONS TO FINISH THE TAF PERIOD.
STRATUS CONTINUES OVER MUCH OF SOUTH CENTRAL NEBRASKA WITH A
CEILING BETWEEN 500 AND 700FT AGL. PATCHY FOG WILL ALSO REMAIN
POSSIBLE ACROSS SOUTH CENTRAL NEBRASKA THROUGH MID MORNING...BUT
THE VISIBILITY AT GRI IS EXPECTED TO REMAIN GREATER THAN 6SM.
STRATUS IS EXPECTED TO BREAK APART AND LIFT BY LATE MORNING...THUS
THE VFR FORECAST STARTING 17Z. STRATUS IS THEN EXPECTED TO
REDEVELOP TONIGHT INTO SATURDAY MORNING...HOWEVER AT THIS TIME
THIS CEILING IS NOT EXPECTED TO DROP BELOW 1000FT AGL...SO FOR NOW
WILL GO WITH AN MVFR CEILING STARTING 05Z. GUIDANCE ALSO SUGGESTS
PATCHY FOG WILL BE POSSIBLE TOWARDS SUNRISE SATURDAY...WITH
VISIBILITY RESTRICTION PERHAPS APPROACHING 5SM. THE SURFACE WIND
WILL REMAIN LIGHT THROUGH THE TAF PERIOD...REMAINING FROM THE
EAST/SOUTHEAST FOR THE MOST PART.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...BRYANT
SHORT TERM...BRYANT
LONG TERM...HALBLAUB
AVIATION...BRYANT
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1015 AM EDT FRI AUG 16 2013
.SYNOPSIS...
SURFACE HIGH PRESSURE CENTERED OVER THE MID-ATLANTIC WILL EXTEND
SOUTHWARD INTO THE CAROLINAS THROUGH THE WEEKEND... AS WEAK WAVES OF
LOW PRESSURE DEVELOP ALONG A STALLED FRONT ACROSS THE DEEP SOUTH AND
SOUTHEAST COAST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1015 AM FRIDAY...
A 1022MB SURFACE HIGH OVER PA/MD EXTENDS SOUTH INTO THE CAROLINAS
THIS MORNING...WITH A STATIONARY FRONT DRAPED ACROSS COASTAL SC AND
GEORGIA IN A CAD-LIKE PATTERN. ALOFT...AND UPPER JET STREAK
EJECTING OUT OF THE BASE OF THE LW TROUGH IS EVIDENT IN WATER VAPOR
IMAGERY OVER NORTHERN GEORGIA. IN RESPONSE...WIDESPREAD PRECIP HAS
BROKEN OUT OVER THE WESTERN HALF OF SC...BUT IS STRUGGLING TO MOVE
NORTH OF THE 925-850MB FRONTAL ZONE...WHICH IS LOCATED NEAR THE
NC/SC BORDER. MID/HIGH CLOUDS ARE POURING INTO THE CWA FROM THE
SOUTHWEST...BUT UNTIL THE 850MB FRONT BEGINS TO PUSH NORTH...WHICH
WILL HAPPEN ONLY SLOWLY BETWEEN NOW AND 00Z THIS EVENING...PRECIP
WILL CONTINUE TO STRUGGLE TO MOVE INTO THE DRY AIR RIDGE.. WITH
SUPPORT FROM HRRR AND OTHER HI-RES WRF MODELS...EXPECT PRECIP TO
SPREAD MORE EAST THAN NORTH ALONG THE BETTER LOW-LEVEL FORCING
THROUGH EARLY AFTERNOON. HAVE REMOVED POPS FROM THE NORTHERN
PIEDMONT AND NORTHERN COASTAL PLAIN...WITH A VERY TIGHT GRADIENT
NEAR THE HWY 64 CORRIDOR AND CATEGORICAL POPS NEAR THE SC BORDER
WILL MAKE SOME SMALL ADJUSTMENTS TO HIGHS BASED ON THE LACK OF
PRECIP FOR MOST OF THE CWA...BUT INCREASING CLOUD COVER WILL STILL
TEMPER HEATING AND THE PREVIOUS FORECAST APPEARS TO BE MOSTLY IN
TRACK. HIGHS IN THE UPPER 60S IN THE SOUTHWEST AND UPPER 70S IN
THE NORTHEAST. -SMITH
TONIGHT...A STRONGER MID-UPPER LEVEL S/W SEEN ON WATER VAPOR IMAGERY
DIVING SWD ACROSS THE CENTRAL PLAINS THIS MORNING WILL DIG INTO THE
BOTTOM OF THE L/W TROUGH....BACKING OUR MID-UPPER LEVEL FLOW TO A
MORE SWLY DIRECTION. IN ADDITION THIS FEATURE WILL ENHANCE THE SLY
FLOW A FEW THOUSAND FEET ABOVE THE SURFACE...INCREASING ISENTROPIC
LIFT. THIS WILL LEAD TO RAIN/RAIN SHOWERS BECOMING WIDESPREAD AND
INCREASE IN INTENSITY ACROSS CENTRAL NC TONIGHT. HAVE INCREASED POPS
TO CATEGORICAL OVER THE SW TWO-THIRDS OF THE FORECAST AREA WITH
LIKELY POPS OVER THE NE. MIN TEMPS LOWER 60S NW TO THE UPPER 60S SE.
&&
.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 AM FRIDAY...
SATURDAY...THE RAIN OVERNIGHT WILL LOCK IN A HYBRID COLD AIR DAMMING
AIR MASS ACROSS THE PIEDMONT. CONTINUED ISENTROPIC LIFT IN
CONJUNCTION OF THE AREA OF LOW PRESSURE OVER THE LOWER MS VALLEY
WILL CAUSE WIDESPREAD LOW CLOUDS AND PERSISTENT RAIN. THIS WILL
RESULT IN A DIURNAL TEMP RECOVERY OF NO MORE THAN 4-5 DEGREES ACROSS
THE NW PIEDMONT...AND 5-7 DEGREES ACROSS THE REMAINDER OF THE
PIEDMONT AND COASTAL PLAIN. MAX TEMPS MID-UPPER 60S NW TO MID-UPPER
70S FAR SE.
HAVE INCREASED POPS TO CATEGORICAL SATURDAY AND LOWERED
MAX TEMPS A DEGREE OR TWO FROM THE PREVIOUS FORECAST. WHILE RAIN
WILL OCCUR FOR MOST OF THE DAY...NOT ANTICIPATING AMOUNTS THAT WOULD
WARRANT THE ISSUANCE OF A FLASH FLOOD WATCH. THAT BEING SAID...WHERE
POCKETS OF MODERATE RAINFALL DUE SET-UP...RAINFALL RATES OF A THIRD
TO A HALF INCH PER HOUR FOR A FEW HOURS WILL CAUSE EXTENSIVE PONDING
OF WATER AND NUISANCE FLOODING OF POOR DRAINAGE AREAS.
SATURDAY NIGHT...CONTINUED SW FLOW ALOFT WITH EMBEDDED DISTURBANCES
INTERACTING WITH THE MOISTURE RICH AIR MASS AND CONTINUED LOW LEVEL
OVERRUNNING WILL MAINTAIN HIGHER THAN NORMAL POPS ACROSS CENTRAL NC.
EXPECT LIKELY POPS TO SUFFICE BUT WOULD NOT BE SURPRISED IF
CATEGORICAL POPS NEEDED IN LATER FORECAST ISSUANCE. TEMPS WILL HOLD
STEADY OR ONLY LOWER A FEW DEGREES FROM OBSERVED HIGH TEMPS ON
SATURDAY. MAY SEE WIDESPREAD AREAS OF FOG DEVELOP OVERNIGHT...
ESPECIALLY ACROSS THE PIEDMONT. MIN TEMPS LOW-MID 60S PIEDMONT TO
THE UPPER 60S IN THE COASTAL PLAIN AND SANDHILLS.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 300 AM FRIDAY...
THE MEDIUM RANGE PORTION OF THE FORECAST WILL TRANSITION FROM A WARM
SEASON CAD EVENT OVER THIS WEEKEND TO MORE TYPICAL AFTERNOON AND
EVENING SCATTERED SHOWERS AND STORMS PATTERN AND NEAR NEAR NORMAL
TEMPS BY NEXT WEEK
SUNDAY AND SUNDAY NIGHT:
THE PRIMARY SURFACE LOW ASSOCIATED WITH THE SYSTEM MENTIONED IN THE
NEAR/SHORT TERM PARTS OF THE FORECAST IS EXPECTED TO LIFT
NORTHEASTWARD FROM THE NC COAST SUNDAY MORNING TO OFF THE
VA/MID-ATLANTIC COAST BY SUNDAY AFTERNOON/EVENING. HOWEVER... MOST
GUIDANCE SHOWS CONTINUED GOOD CHANCES FOR PRECIP ACROSS OUR
NORTHWEST/WEST ASSOCIATED WITH WEAK ISENTROPIC UPGLIDE AND A
POSSIBLE IMPULSE ALOFT MOVING THROUGH THE SOUTH-SOUTHWESTERLY FLOW.
HOWEVER... PRECIP AMOUNTS ARE EXPECTED TO BE LIGHTER THAN ON
SATURDAY. FOR LOCATIONS ACROSS THE NORTHWEST/WEST WHERE THE CAD WILL
HOLD... EXPECT AN OVERCAST... DAMP/WET... COOL DAY. FURTHER EAST AND
SOUTHEAST ACROSS OUR COASTAL PLAIN AND EASTERN SANDHILL COUNTIES
EXPECT WE WILL SEE MORE ISOLATED TO SCATTERED ACTIVITY ON SUNDAY. WE
WILL SEE THE COASTAL FRONT REMAIN TO THE EAST OF THE AREA STILL.
HOWEVER... THE CAD BOUNDARY MAY RETREAT TO THE WEST OF THIS AREA. IF
WE DO SEE A FEW BREAKS IN THE CLOUDS BY AFTERNOON WE MAY SEE SOME
INSTABILITY DEVELOP... RESULTING IN A CHANCE OF SOME SHOWERS AND
EVEN SOME STORMS. FOR NOW WILL GO WITH CHANCE POPS FOR ALL DAY
SUNDAY HERE... WITH THE MAIN THREAT FOR ANY STORMS EXPECTED IN THE
AFTERNOON. FOR LOCATIONS THAT DO SEE THE CAD BOUNDARY RETREAT WE
WILL SEE TEMPS WARM UP SOME... BUT STILL BELOW SEASONAL NORMS.
EXPECT HIGHS SUNDAY WILL RANGE FROM THE LOWER 70S NW TO LOWER 80S TO
MAYBE EVEN MID 80S SE.
WILL CONTINUE TO ADVERTISE A CHANCE OF SHOWERS/RAIN ON SUNDAY NIGHT
ACROSS THE AREA. HOWEVER... THE TROUGH ALOFT CENTERED TO OUR WEST
ACROSS THE OH/TN VALLEY WILL WEAKEN AND BEGIN LIFTING NORTHEASTWARD.
LOW TEMPS MONDAY MORNING ARE EXPECTED TO BE IN THE 66-71 DEGREE
RANGE IN A NW TO SE FASHION.
MONDAY THROUGH THURSDAY:
THE TROUGH ALOFT MENTIONED ABOVE WILL CONTINUE TO WEAKEN AS IT
SLOWLY LIFT NORTHEASTWARD EARN NEXT WEEK. HOWEVER... MEDIUM RANGE
MODEL GUIDANCE HAS BEEN HINTING AT THE POSSIBILITY OF THE WEAKENING
SHEAR-AXIS LINGERING ACROSS THE AREA. GIVEN THE EXPECTED LINGERING
MOIST LOW LEVEL AIRMASS OVER OUR REGION AND PW`S GENERALLY RANGING
FROM 1.5 TO 2.0 INCHES EXPECT WE WILL SEE AT LEAST ISOLATED TO
SCATTERED AFTERNOON/EVENING CONVECTION EACH DAY... ESPECIALLY ON
MONDAY AND TUESDAY... WITH THE POTENTIAL FOR A LINGERING CAD
BOUNDARY ON MONDAY. THIS PATTERN WILL YIELD A TRANSITION BACK TO
NEAR NORMAL TEMPS BY MID/LATE WEEK AND A MORE TYPICAL SUMMERTIME
WEATHER.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 745 AM FRIDAY...
AVIATION WEATHER CONDITIONS ACROSS CENTRAL NC WILL SLOWLY
DETERIORATE FROM THE SOUTH LATER THIS MORNING...ESPECIALLY AFTER
15Z...AS AN UPPER LEVEL DISTURBANCE LIFTS NEWD TOWARD THE CAROLINAS.
THIS WEATHER FEATURE WILL STRENGTHEN THE SLY WINDS A FEW THOUSAND
FEET ABOVE SURFACE...PULLING MOISTURE OVER THE COOL DRY STABLE AIR
MASS AT THE SURFACE. THIS WILL CAUSE CLOUD BASES TO LOWER AND
POCKETS OF LIGHT RAIN TO BREAK OUT. THESE POCKETS OF RAIN WILL
FURTHER SATURATE THE LOW LEVEL AIR MASS...LEADING TO WIDESPREAD MVFR
CEILINGS IN THE KFAY VICINITY BY EARLY AFTERNOON...AND AT KRDU AND
KRWI BY LATE AFTERNOON. CEILINGS WILL LIKELY LOWER INTO THE MVFR
CATEGORY IN THE TRIAD BY SUNSET. AREAS OF RAIN ARE EXPECTED TO
BECOME NUMEROUS OVER THE SOUTH BY LATE MORNING...AND OVER THE
NORTHERN COUNTIES BY LATE AFTERNOON-EARLY EVENING...RESULTING IN
MVFR/IFR VISIBILITIES IN RAIN AND/OR FOG. WIDESPREAD IFR CONDITIONS
DUE TO LOW CLOUDS AND FOG ANTICIPATED FOR TONIGHT.
ADVERSE AVIATION WEATHER CONDITIONS WILL PERSIST INTO SATURDAY AND
SATURDAY NIGHT WITH PERIODS OF WIDESPREAD LIGHT-MODERATE RAIN AND
CEILINGS IN THE IFR/LOW END MVFR RANGE THROUGH THE ENTIRE PERIOD.
AVIATION CONDITIONS WILL REMAIN PROBLEMATIC SUNDAY THOUGH THE AREAS
OF RAIN WILL BECOME LESS NUMEROUS...ESPECIALLY ACROSS THE COASTAL
PLAIN AND SANDHILLS. HOWEVER WIDESPREAD MVFR CEILINGS WITH AREAS OF
IFR WILL PERSIST THROUGH SUNDAY INTO SUNDAY NIGHT.
ANY IMPROVEMENT IN AVIATION WEATHER CONDITIONS WILL BE SLOW TO OCCUR
MONDAY INTO TUESDAY. THE AIR MASS IS PROJECTED TO REMAIN QUITE MOIST
WITH A CONTINUED THREAT FOR SHOWERS. IN ADDITION...THE PROBABILITY
OF A FEW THUNDERSTORMS WILL INCREASE MONDAY AFTERNOON AND AGAIN
TUESDAY AFTERNOON.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BADGETT
NEAR TERM...WSS/SMITH
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
703 AM EDT FRI AUG 16 2013
.SYNOPSIS...
A WEDGE OF COOL HIGH PRESSURE WILL REMAIN IN PLACE OVER THE
CAROLINAS THROUGH THE WEEKEND...THEN GRADUALLY WEAKEN EARLY NEXT
WEEK. A STRONG UPPER TROUGH DEVELOPING OVER THE MISSISSIPPI VALLEY
WILL BRING TROPICAL MOISTURE OVER THE HIGH PRESSURE WEDGE TODAY AND
OVER THE WEEKEND...BRINGING WIDESPREAD SHOWERS TO THE AREA. DRIER
AND WARMER WEATHER IS EXPECTED TO RETURN BY THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 530 AM...RAIN RATES WITHIN BLOSSOMING AREA OF PRECIP IS A BIT
SURPRISING AS IT ENTERS OUR SRN COUNTIES...WITH POCKETS OF 1-2"/HR
INSTANTANEOUS RATES ON DUAL POL. THE LATEST MESOSCALE GUIDANCE...6Z
NAM...AND THE RAP ALL AGREE ON THIS PRECIP SHIELD EXPANDING AND
STREAKING NEWD ACRS ZONES ALONG AND SOUTH OF I-85 THIS MORNING. I
HAVE BUMPED POPS UP TO CATEGORICAL...AND TWEAKED THE QPF UP WHERE
THIS RAIN SHIELD GOES. TRENDS ALSO SUGGEST THAT THE I-40 CORRIDOR
WILL HAVE A DRIER MORNING THAN FCST...SO I CUT BACK POP THERE.
OTHERWISE...FCST ON TRACK.
AS OF 300 AM...A POTENT LOBE OF VORTICITY WILL ROUND THE BASE OF AN
UPR LONGWAVE TROF AXIS INVOF THE MID SOUTH EARLY THIS MORNING...THEN
CROSS THE TN VLY TO OUR CWFA THIS AFTN/EVE. THE WAVE WILL PROVIDE
MID-UPR FORCING WHICH WILL BE COUPLED WITH INCREASING LLVL LIFT
ALONG A STALLED FRONTAL BNDRY DRAPED ACRS THE SOUTHEAST STATES. A
WEAK WAVE IS PROGGED TO FORM ON A 850 MB FRONTAL ZONE INVOF
AL...INCREASING THE LLVL S/SELY FLOW ATOP A COLD AIR DAMMING WEDGE.
MODELS ARE IN DECENT AGREEMENT ON THIS SETUP...BUT FOR SOME REASON
STILL DIFFER GREATLY ON THE EXACT PLACEMENT/TIMING/MAGNITUDE OF QPF
THRU TONIGHT (AND THRU THE WEEKEND). THE NAM CONTINUES TO BE AN
OUTLIER ON A BULLSEYE OF 2-2.5" ACRS THE UPSTATE AND NE GA BY 00Z
THIS EVENING. THE NAM CONTINUES THE HIGH QPF RESPONSE INTO THE NC
PIEDMONT/FOOTHILLS TONIGHT. THE OTHER OP GUIDANCE IS A LTL MORE IN
LINE WITH GFS...HAVING LOWER MAGNITUDE...AND KEEPING THE HEAVIEST
RAIN TO OUR SOUTHEAST CLOSER TO THE SFC FRONT. I THINK THIS MAKES
SENSE...AS THE BEST PWATS/MOISTURE FLUX AND UPR DIVERGENCE WILL BE
THERE.
SO THE FCST FOR TODAY IS FOR RAIN/SHWRS TO SPREAD IN FROM THE
SOUTH...WITH GREATEST COVERAGE REMAINING ACRS ALONG AND SOUTH OF
I-85. THE RAIN AND CLOUDS SHUD LOCK IN UNSEASONABLY COOL TEMPS FOR
THE DAY...AS WEDGE BECOMES DIABATICALLY ENHANCED. A CONSENSUS BLEND
RESULTS IN MAX TEMPS 15-20 DEG BELOW NORMAL. TEMPS MAY STRUGGLE TO
REACH 70 ACRS PORTIONS OF THE UPSTATE AND SRN NC PIEDMONT...IF RAIN
IS HEAVIER AND/OR MORE PERSISTENT THAN EXPECTED.
TONIGHT...TIMING DIFFERENCES ALREADY MAKE FOR UNCERTAINTY IN THE
HOURLY POP TRENDS. IT SEEMS THERE MAY BE A RELATIVE LULL IN ACTIVITY
THIS EVENING...AS ONE WAVE PASSES BY. HOWEVER...THE UPR TROF WILL
CONTINUE TO AMPLIFY...WITH ANOTHER ROUND OF STRONGER QG FORCING AND
BETTER ISENT LIFT DEVELOPING OVERNIGHT. HAVE POPS RAMPING BACK UP TO
CATEGORICAL IN THE EAST. AGAIN...QPF IS EXPECTED TO BE SOAKING...BUT
NOT EXCESSIVE. I WENT CLOSE TO WPC FOR ALL THE 6-HOURLY QPF GRIDS IN
THE NEAR TERM.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 220 AM FRIDAY...THE SHORT TERM FCST PICKS UP AT 12Z ON
SATURDAY WITH GUIDANCE IN FAIRLY GOOD AGREEMENT ON AN UPPER LOW
DEVELOPING OVER THE MID SOUTH BY EARLY SAT. THIS LOW REMAINS NEARLY
STATIONARY SAT NITE WITH A SLIGHT NORTHEASTWARD DRIFT ON SUN AND
THEN LIFTING ON SUN NIGHT AND INTO MON. AT THE SFC...THE FCST AREA
WILL REMAIN UNDER THE COOL AIR WEDGE THRU THE END OF THE PERIOD
EARLY MON. THERE ARE SOME NOTABLE DISCREPANCIES BETWEEN THE
OPERATIONAL MODELS WRT HOW QUICKLY THE WEDGE DISSIPATES WITH THE GFS
TRYING TO MAINTAIN THE FEATURE LONGER THAN THE NAM AND ECMWF.
REGARDLESS...AS WE MOVE INTO THE MEDIUM RANGE THE BERMUDA SFC HIGH
WILL REESTABLISH ITSELF AND BRING SLY LOW LVL FLOW BACK TO THE
REGION. WITH THAT SAID...POPS WILL BE HIGH OVER MOST OF THE CWFA
THRU SUN EVENING AS FAVORABLE ISENTROPIC LIFT AND HIGH PWAT VALUES
PERSIST. BY EARLY MONDAY...LIKELY POPS WILL SHIFT TO THE EAST AS THE
BEST UPPER LVL SUPPORT MOVES TOWARDS THE COAST. GUIDANCE BLEND
CONTINUES TO SUGGEST MODERATE QPF AMOUNTS AT BEST WITH MINIMAL
INSTABILITY THRU SUN. I KEPT TEMPS WELL BELOW CLIMO WITH VALUES
STEADILY RISING EACH DAY. BY MON...WE ARE BACK IN THE LOW 80S OVER
THE UPSTATE AND PIEDMONT.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 2 AM FRIDAY...THE MEDIUM RANGE FCST PICKS UP AT 12Z ON MONDAY
WITH THE UPPER LEVEL TROUGH ERODING AND SHIFTING EASTWARD. THE COOL
WEDGE WILL GRADUALLY DISSIPATE BY THE MIDDLE OF NEXT WEEK...AS A
SURFACE HIGH BUILDS IN OVER THE CWA AND AN UPPER RIDGE GRADUALLY
SLIDES EASTWARD ACROSS THE CONUS. THIS LENDS ITSELF TO A DRIER
PERIOD...WITH A RETURN TO NORMAL SUMMERTIME DIURNAL POPS FOR THE
MIDDLE AND END OF NEXT WEEK. THE DRYING TREND WILL ALLOW
TEMPERATURES TO INCREASE BACK TO THE LOW TO MID 80S BY THE MIDDLE OF
NEXT WEEK...THOUGH HIGHS WILL STILL REMAIN A FEW DEGREES BELOW
NORMAL.
&&
.AVIATION /11Z FRIDAY THROUGH TUESDAY/...
AT KCLT...CONDITIONS HAVE BEEN TRENDING A LITTLE MORE PESSIMISTIC
SINCE THE 06Z TAFS. A RAIN SHIELD HAS SPREAD ACRS THE UPSTATE AND
WILL AFFECT THE KCLT TERMINAL THIS MORNING. RAIN RATES ARE EXPECTED
TO BE ON THE LIGHT SIDE...BUT BRIEF MVFR VSBY OR CIG RESTRICTIONS
WHEN THE RAIN MOVES THRU CANNOT BE RULED OUT. CIGS SHUD LWR TO 4000
FT BY ABOUT 14Z...THEN BEGIN TO LOWER TOWARD MVFR THIS AFTN.
GUIDANCE IS VERY DIVERGENT ON THE CIG TRENDS...SO CONFIDENCE IS LOW
ON WHEN THINGS REALLY START TO DETERIORATE. AFTER
SUNSET...CONFIDENCE INCREASES THAT LOW CIGS WILL BECOME
PERSISTENT...AS MORE SHRA MOVE INTO THE AREA. WINDS WILL REMAIN NE
OR ENE...AND INCREASE TO 8-10 KTS BY LATE MORNING.
ELSEWHERE...RAIN IS SPREADING INTO THE UPSTATE SITES BY THE TIME THE
12Z TAFS BECOME VALID. THE RAIN IS LIGHT SO FAR...BUT RESTRICTIONS
IN VSBY AND/OR CIGS ARE POSSIBLE. THE RAIN WILL TAPER OFF SOMEWHAT
BY EARLY AFTN...WITH GUIDANCE RATHER DIVERGENT ON WHETHER CIGS
IMPROVE OR CONTINUE TO LINGER IN THE MVFR RANGE. WENT WITH A
COMPROMISE FOR THE CIG TRENDS. TONIGHT...MOISTURE INCREASES AND CIGS
ARE EXPECTED TO LOWER TO IFR BY THE END OF THE TAF PERIOD. FOR KAVL
AND KHKY...TRENDS WILL BE SLOWER...AS MORE DRY AIR AND LESS PRECIP
EXPECTED TODAY. WINDS WILL OUT OF THE NE (EXCEPT SE AT KAVL)...AND
GENERALLY UNDER 10 KTS.
OUTLOOK...A STATIONARY FRONT IS EXPECTED TO REMAIN SOUTH AND EAST OF
THE FORECAST AREA THROUGH THE WEEKEND...KEEPING THE AREA IN A COOL
MOIST WEDGE OF HIGH PRES. RESTRICTIVE CIGS AND VSBYS WILL LIKELY
PERSIST ACRS THE REGION THRU AT LEAST SUNDAY...THEN SOME IMPROVEMENT
TO MOSTLY VFR EXPECTED EARLY NEXT WEEK...AS THE WEDGE ERODES.
CONFIDENCE TABLE...
11-17Z 17-23Z 23-05Z 05-11Z
KCLT MED 77% HIGH 91% MED 79% HIGH 91%
KGSP MED 79% HIGH 80% HIGH 91% HIGH 95%
KAVL HIGH 87% HIGH 100% HIGH 89% HIGH 95%
KHKY HIGH 100% HIGH 100% HIGH 91% HIGH 94%
KGMU MED 73% MED 77% HIGH 90% HIGH 97%
KAND MED 63% HIGH 83% HIGH 93% HIGH 91%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.CLIMATE...
RECORD LOW MAX TEMPERATURES THIS WEEKEND...
AUG 16 AUG 17 AUG 18
AVL...62 1964 72 1986 70 1905
CLT...64 1964 71 1992 72 1894
GSP...64 1964 71 1971 71 1957
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JPT
NEAR TERM...ARK
SHORT TERM...JPT
LONG TERM...JPT
AVIATION...ARK
CLIMATE...
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
932 AM CDT FRI AUG 16 2013
.UPDATE...
CLOUDS IN PLACE THIS MORNING. UPPER LEVEL TROUGH EXPECTED TO
BEGIN STRENGTHENING TODAY. 18Z PROGS SHOW CAPPING IN PLACE BUT
MOISTURE LEVELS ARE ON THE INCREASE. WEAK SFC TROUGH WILL STRETCH
FROM NRN MS THROUGH MIDDLE TN THIS AFTERNOON. THIS WILL SERVE AS
SOME WEAK FORCING WHICH MAY SPAWN SOME SHOWER ACTIVITY TODAY.
LATEST HRRR STILL IN SUPPORT OF SOME SHOWER DEVELOPMENT. HOWEVER...ANY
ACTIVITY SHOULD REMAIN ON THE LIGHT SIDE.
FOR THE FORECAST...CANNOT SEE A REASON TO CHANGE ANYTHING AT THIS
TIME. THE 18Z TEMPS PROG APPEARS TO BE IN LINE WITH THE CURRENT
FORECAST MAXES. INSTABILITY IS QUITE WEAK SO WILL CONTINUE WITH
JUST A SLIGHT CHANCE OF THUNDER.
&&
.PREV DISCUSSION... /ISSUED 641 AM CDT FRI AUG 16 2013/
UPDATE...FOR 12Z AVIATION FORECASTS.
AVIATION...EXPECT VFR CIGS THROUGHOUT THE TAF PERIOD. DESPITE
CIGS...HOWEVER...SOME VIS RESTRICTIONS ARE LIKELY OVERNIGHT AT
CKV/CSV DUE TO PATCHY FOG. SCATTERED -SHRA/-TSRA ARE EXPECTED TO
OCCUR, ESPECIALLY IN THE AFTERNOON AND EVENING. HOWEVER, WOULD BE
HARD PRESSED TO DETERMINE IF OR WHEN A -SHRA/-TSRA MIGHT AFFECT
ANY PARTICULAR TERMINAL. THUS, WILL LEAVE MENTION OF PRECIP OUT OF
TAFS FOR NOW. LIGHT EAST-T0-NORTHEAST WINDS ARE ANTICIPATED
THROUGHOUT THE TAF PERIOD.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION...UPDATED
NWS MORRISTOWN TN
1010 AM EDT FRI AUG 16 2013
.DISCUSSION...
ANALYSIS OF RAOBS ACROSS THE REGION AND SATELLITE IMAGERY SHOW A
DEFORMATION ZONE AT 850 MB ACROSS THE SOUTHERN APPALACHIANS. MOST
PRECIP IS STAYING SOUTH OF THE AXIS OF DEFORMATION ACROSS GA/SC. A
FEW SHOWERS ARE SPREADING INTO THE SOUTHERN TN VALLEY AND SW
NC...BUT ARE MAKING SLOW NORTHWARD PROGRESS. WITH THE UPPER LOW
STAYING STATIONARY OVER AL TODAY...WE SHOULD NOT SEE MUCH CHANGE TO
THIS PATTERN. POPS WILL BE LOWERED ACROSS THE BOARD. THE EXTENSIVE
CLOUD COVER WE ARE SEEING THIS MORNING APPEARS WELL ENTRENCHED
BASED ON AREA 12Z SOUNDINGS AND RUC FORECAST SOUNDINGS...SO TEMPS
WILL BE LOWERED AS WELL...ESPECIALLY IN SOUTHERN AREAS.
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DGS
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1030 AM MDT FRI AUG 16 2013
.UPDATE...QUIET DAY TODAY AS AN UPPER LEVEL RIDGE BUILDS OVER THE
REGION. LOW CLOUDS CREPT INTO THE NORTHEAST CORNER OF COLORADO
OVERNIGHT. THEY HAVE BEEN SLOW TO BURN OFF AND WILL LINGER THROUGH
THE REST OF THE MORNING. DROPPED TEMPERATURES A FEW DEGREES OVER
THE NORTHEAST CORNER WHERE THE CLOUDS ARE.
CUMULUS CLOUDS ARE JUST STARTING TO FORM OVER THE MOUNTAINS. MAY
BE JUST ENOUGH MOISTURE AND INSTABILITY FOR A FEW STORMS OVER
HIGHER TERRAIN. PRECIPITABLE WATER VALUES ARE LESS THAN A HALF
INCH ALONG THE FRONT RANGE...THIS SHOULD KEEP STORMS CONFINED TO
THE HIGHER TERRAIN.
&&
.AVIATION...MID AND HIGH CLOUDS WILL INCREASE THIS AFTERNOON AS
CONVECTIVE CLOUDS SPREAD FROM THE HIGHER TERRAIN TO THE FRONT
RANGE. MAY SEE A FEW STORMS OVER THE HIGHER TERRAIN...BUT THE
AIRMASS WILL BE TOO DRY FOR STORMS OVER THE DENVER AREA. WINDS
WILL BE ON THE LIGHT SIDES THROUGH THE NEXT 24 HOURS.
&&
.PREV DISCUSSION... /ISSUED 315 AM MDT FRI AUG 16 2013/
SHORT TERM...SOME STRATUS AND FOG HAS DEVELOPED EARLY THIS
MORNING OVER THE FAR NERN PLAINS AND MAY EVENTUALLY SPREAD FURTHER
WEST INTO MORGAN AND PARTS OF WELD COUNTY BY 12Z. NEITHER THE RAP
OR HRRR SHOW THIS STRATUS/FOG MOVING INTO THE URBAN CORRIDOR AT
THIS POINT SO WILL KEEP IT EAST OF THE FRONT RANGE.
OTHERWISE AN UPPER RIDGE WILL BUILD OVER WRN COLORADO WITH MAINLY
DRY NNW FLOW ALOFT ACROSS THE AREA. HOWEVER THERE STILL COULD BE
SOME ISOLD HIGHER BASED STORMS OVER THE HIGHER FOOTHILLS...MTNS
AND OVER THE PALMER DIVIDE FM MID AFTN THRU THE EARLY EVENING
HOURS. HIGHS THIS AFTN WILL BE A FEW DEGREES WARMER THAN FRIDAY IN
MOST LOCATIONS AS 850-700 MB TEMPS RISE A COUPLE OF DEGREES.
LONG TERM...STRONG...HIGH AMPLITUDE UPPER RIDGE OVER THE DESERT
SOUTHWEST/EASTERN GREAT BASIN/ROCKY MOUNTAIN/WESTERN GREAT PLAINS
REGIONS DOES NOT APPEAR TO BE GOING ANYWHERE TOO SOON ACCORDING TO
THE DETERMINISTIC MODELS AND THEIR ENSEMBLE MEMBERS. THE 500 MB
RIDGE APPEARS TO MEANDER BACK AND FORTH/EAST-WEST/ DURING THE
PERIOD...WHICH CAUSES SUBTLE DAY-TO-DAY SHIFTS IN THE AXIS OF
MONSOONAL MOISTURE PLUME CONNECTED TO THE LOWER DESERTS OF ARIZONA
AND NEW MEXICO. MODELS DIFFER SOME WITH ITS POSITION AND ITS
STRENGTH...BUT OVERALL...THIS CONVEYOR BELT OF SUBTROPICAL
MOISTURE APPEARS TO REMAIN LARGELY ALONG AND WEST OF THE
CONTINENTAL DIVIDE THROUGH THE MIDDLE OF NEXT WEEK. RAIN/T-STORM
CHANCES WILL BE AT THEIR LOWEST THIS WEEKEND FOR NORTH CENTRAL
AND NORTHEAST COLORADO...WITH TEMPERATURES LIKELY TO BE THEIR
WARMEST. NOT SURE WE/LL SEE THE NEAR RECORD HIGH TEMPS ADVERTISED
BY THE GFS...PROBABLY MORE LIKE THOSE OFFERED BY THE ECMWF...BUT
STILL 1-3C ABOVE THE AVERAGE FOR THE DATE. NEXT WEEK...MODELS
INDICATE SLIGHT COOLING...WITH TEMPERATURES RETURNING TO NEAR
AVERAGE...ALONG WITH A SLIGHTLY BETTER CHANCE OF THE AFTERNOON/
EVENING T-STORMS...MAINLY FOR THE MTNS AND HIGH FOOTHILLS. AT THIS
TIME...T-STORMS WITHIN THE CWFA ARE NOT EXPECTED TO PRODUCE HEAVY
RAIN LIKE THOSE OF THE PAST COUPLE OF WEEKS DUE LARGELY TO LOWER
SPECIFIC HUMIDITY AND PRECIPITABLE WATER VALUES. PORTIONS OF
NORTHEAST/EAST CENTRAL COLORADO MAY NOT SEE ANY PRECIP AT ALL
DURING THIS PERIOD.
AVIATION...WINDS WERE DRAINAGE EARLY THIS MORNING AS A WK DENVER
CYCLONE IS WEST OF DIA. BOTH THE RAP AND HRRR SHOW SOME STRATUS
DEVELOPING OVER CNTRL WELD COUNTY BY 12Z HOWEVER NEITHER MODEL
SHOWS IT AFFECTING THE AIRPORT AS WINDS STAY SSW. BY LATE MORNING
THE WK CYCLONE IS FCST TO MOVE SE OF THE AIRPORT WITH WINDS
BECOMING NELY BY 18Z AND CONTINUING THRU THE AFTN HOURS. NO TSTMS
ARE EXPECTED THIS AFTN AS ISOLD ACTIVITY SHOULD STAY OVER THE
HIGHER TERRAIN. FOR THIS EVENING WINDS SHOULD TRANSITION BACK TO
DRAINAGE BY 06Z.
HYDROLOGY...ISOLD HIGH BASED STORMS MAY DEVELOP BY 20Z IN THE
FOOTHILLS HOWEVER THEY WILL ONLY PRODUCE GUSTY WINDS AND LIGHT
RAINFALL.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RJK
LONG TERM....BAKER
AVIATION...MEIER
AREA FORECAST DISCUSSION
NWS JACKSON KY
134 PM EDT FRI AUG 16 2013
.UPDATE...
ISSUED AT 1228 PM EDT FRI AUG 16 2013
LATEST HRRR RUNS ARE CONSISTENT WITH RUNS EARLIER THIS MORNING
POINTING TOWARDS SCATTERED SHOWERS OVER THE SOUTHERN...AND ESPECIALLY
SOUTHWEST PART OF FORECAST AREA. WILL KEEP THE PRECIPITATION FORECAST
AS IS FOR THIS AFTERNOON. MADE SOME MINOR ADJUSTMENTS TO NDFD FOR
LATEST OBSERVATIONAL TRENDS.
UPDATE ISSUED AT 1028 AM EDT FRI AUG 16 2013
A FEW SHOWERS HAVE DEVELOPED OVER SOUTH CENTRAL KY WEST OF OUR
FORECAST AREA AND OVER CENTRAL TN. THE 12Z NAM AND HRRR CONTINUE TO
POINT TOWARDS THE POSSIBILITY OF SHOWERS OVER THE SOUTHERN PART OF
THE FORECAST AREA THIS AFTERNOON...IN GOOD AGREEMENT WITH INHERITED
FORECAST. WILL CONTINUE WITH SAME AREA FOR SHOWER POSSIBILITY THIS
AFTERNOON. EXTENSIVE CLOUD COVER OVER TN HAS WORKED INTO THE SW PART
OF THE FORECAST AREA...AND HAVE MADE ADJUSTMENTS TO SKY COVER GRIDS.
THE CLOUDS WILL INHIBIT CONVECTIVE DEVELOPMENT...AND WILL CHANGE
SCATTERED SHOWERS AND THUNDERSTORMS TO SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS. NDFD AND ASSOCIATED PRODUCTS...INCLUDING ZFP...HAVE
BEEN UPDATED.
UPDATE ISSUED AT 723 AM EDT FRI AUG 16 2013
UPDATED THE FORECAST TO BETTER REFLECT CURRENT CONDITIONS AND MODEL
TRENDS. ONLY HAD TO MAKE MINOR TWEAKS TO THE TEMPERATURES AND DEW
POINTS. THE REST OF THE FORECAST IS ON TRACK.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 225 AM EDT FRI AUG 16 2013
THIS HAS BEEN AN UNUSUAL SUMMER AS IT HAS BE DOMINATED BY A UPPER LOW
OVER THE EASTERN PORTION OF THE US AND THE MODELS ARE ONCE AGAIN
BUILDING ANOTHER UPPER LOW IN OVER SOUTHERN ILLINOIS BY THIS EVENING.
WITH THIS TYPE OF PATTERN...THE POSITION OF THE UPPER LOW WILL BE
CRUCIAL AND WILL MAKE A BIG DIFFERENCE IN FORECAST. THE FORECAST IS
ALSO DIFFICULT DUE TO THE LACK OF ANY STRONG ORGANIZED SYSTEMS. THE
WEATHER WILL TEND TO BE DIURNALLY DRIVEN WITH THE BEST CHANCE FOR
CONVECTION BEING INTO THE AFTERNOON AND EARLY EVENING. WILL HAVE TO
WATCH FOR WEAK DISTURBANCES THAT WILL BE ROTATING AROUND THE LOW AND
WILL BE ABLE TO FOCUS SOME ENHANCED ACTIVITY. AT THIS POINT IN
TIME...CONFIDENCE IS LOW THAT THE MODELS WILL HAVE A GOOD HANDLE ON
THIS YET. FOR TODAY...KEPT THE PRECIPITATION MOSTLY WEST OF I 75 AS
ONLY A PORTION OF THE SYSTEM WILL BE ABLE TO INFLUENCE THE AREA.
THERE IS A MARKED DIFFERENCE IN THE NAM BUFFER SOUNDING FOR LONDON AND
JACKSON. AT JACKSON...THERE IS A PERSISTENT CAP IN PLACE THAT SHOULD
BE ABLE TO SUPPRESS THE CONVECTION THIS AFTERNOON. AT LONDON...THE
CAP DISAPPEARS AFTER 2 PM. FOR TEMPERATURES...WENT WITH THE BLEND AS
THERE IS ACTUALLY QUITE A BIT OF SPREAD BETWEEN THE VARIOUS MODELS.
WHEN THIS OCCURS AND ONE OF THE SOLUTIONS DOES NOT STAND OUT...LIKE
TO GO WITH THE BLEND.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 300 AM EDT FRI AUG 16 2013
THE MODELS WERE IN DECENT AGREEMENT WITH THE OVERALL LARGE SCALE
WEATHER PATTERN IN THE EXTENDED. A PASSING LARGE SCALE UPPER TROUGH
IS EXPECTED TO COMBINE WITH LOW LEVEL MOIST FLOW OFF THE SOUTHWESTERN
ATLANTIC. SOUTHEASTERLY FLOW AROUND THE WESTERN PERIPHERY OF THE
BERMUDA HIGH WILL PROVIDE THE WARM MOIST AIR TO THE REGION. SCATTERED
SHOWERS AND STORMS ARE PROGGED TO FORM MAINLY DURING THE AFTERNOON
AND EVENING HOURS ACROSS CENTRAL AND EASTERN KENTUCKY DURING PEAK
HEATING. THE ACTIVITY IS EXPECTED TO TAPER OFF AFTER SUNSET EACH
DAY...WITH DRY OVERNIGHT PERIODS AND MOSTLY DRY EARLY MORNING PERIODS.
HIGH TEMPERATURES THE FIRST FEW DAYS OF THE PERIOD SHOULD BE COOLER
THAN NORMAL...WITH WIDESPREAD CLOUD COVER AND PRECIPITATION IN THE
FORECAST. HIGHS ON SUNDAY AND MONDAY WILL TOP OUT AROUND 80 DEGREES.
FROM WEDNESDAY ONWARD SHOULD TOP OUT AT OR ABOVE NORMAL...WITH
READINGS IN THE MID TO UPPER 80S EACH DAY UNDER A SOUTHERLY FLOW
REGIME AND PARTLY CLOUDY SKIES. OVERNIGHT LOWS WILL DROP INTO THE
60S...WHICH IS NORMAL FOR THIS TIME OF YEAR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 134 PM EDT FRI AUG 16 2013
HIGH PRESSURE OVER THE OHIO VALLEY WILL KEEP MOSTLY VFR CONDITIONS
ACROSS THE FORECAST AREA THROUGH SATURDAY. ISOLATED THUNDERSTORMS WILL
BE POSSIBLE THIS AFTERNOON MAINLY SOUTH OF LOZ AND SME...CLOSER TO
THE TN BORDER. WHILE SOME FOG IN RIVER VALLEYS CAN BE EXPECTED LATE
TONIGHT...FOG IS NOT EXPECTED TO AFFECT THE TAF SITES. MOISTURE WILL
BE INCREASING ACROSS THE AREA ON SATURDAY AS AN UPPER LEVEL LOW
PRESSURE SYSTEM TAKES SHAPE OVER THE MID MS VALLEY...AND THIS WILL
BRING A BETTER CHANCE OF SCATTERED SHOWERS AND THUNDERSTORMS SATURDAY
AFTERNOON.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...JJ
LONG TERM...AR
AVIATION...SBH
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
111 PM EDT Fri Aug 16 2013
...Updated Aviation Discussion...
...Forecast Update...
Issued at 107 PM EDT Fri Aug 16 2013
Current forecast continues to be on track. Most likely will see a
strong gradient of PoP this afternoon with mostly dry conditions
across southern Indiana and north-central and east-central KY. Best
chances for some light showers would be across south-central KY.
Temperatures have warmed into the mid-upper 70s and highs still look
to top out in the in the mid-upper 70s with some locations reaching
80.
Update issued at 1035 AM EDT Fri Aug 16 2013
Did a very minor update to the grids. Basically adjust T/Td grids
over the next few hours and adjust the clouds and PoPs slightly.
Have a bit of moisture convergence down across south-central KY this
morning which has resulted in some scattered showers. Expect this
to continue through the morning and afternoon hours with the best
coverage remaining across southern KY...and lesser chances as one
heads up to the Ohio River. Afternoon highs in the upper 70s to
around 80 still look attainable.
.SHORT TERM (Now through Saturday)...
Issued at 305 AM EDT Fri Aug 16 2013
The main challenge for today will be precipitation chances over
south central KY. Weak convection formed Thurs due to forcing of an
upper level trough and sfc convergence along an inverted trough over
central TN. A line of showers and isld t-storms resulted Thurs
afternoon/evening and has been slowly dissipating and drifting
northward during the early morning hours. Left over sprinkles may
drift into our south central KY counties this morning around and
just after sunrise. A better chance of rain looks to arrive this
afternoon for south central KY if the inverted sfc trough can drift
far enough northward as the 0Z NAM and 3Z RAP suggest it will.
Expect weakly forced showers and isld t-storms to re-fire along the
boundary by mid to late afternoon and again weaken and diminish
after sunset. Although did increase POPs to 30% along the KY/TN
border, there is still some doubt that the boundary will not make it
this far north so will need to monitor closely today. Went a few
degrees cooler than MOS guidance for high temps and MOS guidance was
a few degrees too warm for Thurs highs. This puts the area in the
upper 70s to around 80 for highs this afternoon.
Tonight expect showers/storms to diminish early over south central
KY and become more focused to our west and south overnight as an
upper level wave drops down into the broad Midwest trough forming a
closed low over the mid Mississippi River Valley by Sat afternoon.
It appears that this feature may help pull the inverted sfc trough
back northward over central KY for Sat providing a better focus for
showers/t-storms. Although wind fields and overall forcing still
look meager, perhaps better overall coverage of convection can be
achieved over central KY Sat afternoon. Any storms that develop
today or Sat should not pose a severe weather threat and would be
brief/weak in nature.
Temperatures tonight should fall into the upper 50s and lower 60s
for lows. Highs Saturday afternoon will warm into the upper 70s and
lower 80s with the warmer spots located over southern Indiana which
only has a 20% chance of rain.
.LONG TERM (Saturday Night through Thursday)...
Issued at 300 AM EDT FRI Aug 16 2013
The extended forecast, starting late Saturday, will feature a
wholesale change in the configuration of the jet stream. The polar
jet, which has for several weeks now been locked in a cyclonic flow
around the Great Lakes, will retreat north into a zonal flow along
or just north of the Canadian Border. This pattern is common in
July, during high summer, and will allow a substantial late summer
warmup for the upper Midwest and the Great Lakes.
As this jet lifts north however, a digging shortwave now moving
south across Kansas will help to elongate a residual trough over the
Lower Ohio Valley. Indeed, both the NAM and the GFS closes off this
trough and creates a shallow cutoff low over the Missouri Bootheel
late Saturday. This feature will lift northeast and become absorbed
into the westerlies over Ohio by late Monday.
A tropical disturbance, now over the Yucatan Peninsula, is forecast
to slowly move northwest and may develop in to a tropical storm early
next week, Regardless of the eventual path of this feature, rich
Gulf moisture will stream northeast out of the western Gulf into the
eastern Tennessee Valley and the southern Appalachians from Sunday
into at least Tuesday of next week.
On Sunday and Monday, central Kentucky will lie in a transition
region between mostly clear skies and subsidence across northern
Indiana and the northwest fringes of an increasingly humid airmass
developing over the southern Appalachians. Weak to moderate
instability both Sunday and Monday afternoon will lead to isolated
to scattered showers and thunderstorms, especially along and south
of the Bluegrass Parkway. Think that coverage may be best Sunday
afternoon, aided by the presence of a weak 850mb circulation over
central Kentucky and a possible inverted trough extending northwards
across the Tennessee Valley. Any convection that does develop Sunday
or Monday will be diurnally driven, dissipating in the evening
hours.
Winds early next week will stay quite light. Temperatures, moderated
by possible cloudiness and the continued presence of troughing, will
remain below normal, with highs in the lower 80s by day and the mid
60s at night.
Heights begin to rise over the Lower Ohio Valley Tuesday as the last
vestiges of the eastern trough exits. Weak subsidence associated
with a slowly eastward propagating 500mb ridge over the southern plains will
most likely keep Tuesday through Thursday dry, as is shown in the
preferred ECMWF. We will experience typical late summer weather with
very light winds and pressure gradients, coupled with moderate
humidities and temperatures that, by Thursday afternoon may warm
into the upper 80s to around 90.
&&
.AVIATION (18Z TAF Update)...
Issued at 110 PM EDT Fri Aug 16 2013
VFR conditions are expected to continue through the upcoming TAF
period. Inverted surface trough and moisture convergence axis will
remain in place this afternoon across south-central KY. This
feature should continue to serve as a focus for convection this
afternoon. Showers and perhaps a thunderstorm will be
possible...mainly in the south between KBWG and KSME. So, will keep
a mention of VCSH in the BWG TAF. Light and variable to light NE
winds are expected at all the terminals this afternoon and this
evening. VFR conditions are expected to hold overnight as well and
into the day on Saturday.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........MJ
Short Term.....AMS
Long Term......JSD
Aviation.......MJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
1229 PM EDT FRI AUG 16 2013
.UPDATE...
ISSUED AT 1228 PM EDT FRI AUG 16 2013
LATEST HRRR RUNS ARE CONSISTENT WITH RUNS EARLIER THIS MORNING
POINTING TOWARDS SCATTERED SHOWERS OVER THE SOUTHERN...AND ESPECIALLY
SOUTHWEST PART OF FORECAST AREA. WILL KEEP THE PRECIPITATION FORECAST
AS IS FOR THIS AFTERNOON. MADE SOME MINOR ADJUSTMENTS TO NDFD FOR
LATEST OBSERVATIONAL TRENDS.
UPDATE ISSUED AT 1028 AM EDT FRI AUG 16 2013
A FEW SHOWERS HAVE DEVELOPED OVER SOUTH CENTRAL KY WEST OF OUR
FORECAST AREA AND OVER CENTRAL TN. THE 12Z NAM AND HRRR CONTINUE TO
POINT TOWARDS THE POSSIBILITY OF SHOWERS OVER THE SOUTHERN PART OF
THE FORECAST AREA THIS AFTERNOON...IN GOOD AGREEMENT WITH INHERITED
FORECAST. WILL CONTINUE WITH SAME AREA FOR SHOWER POSSIBILITY THIS
AFTERNOON. EXTENSIVE CLOUD COVER OVER TN HAS WORKED INTO THE SW PART
OF THE FORECAST AREA...AND HAVE MADE ADJUSTMENTS TO SKY COVER GRIDS.
THE CLOUDS WILL INHIBIT CONVECTIVE DEVELOPMENT...AND WILL CHANGE
SCATTERED SHOWERS AND THUNDERSTORMS TO SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS. NDFD AND ASSOCIATED PRODUCTS...INCLUDING ZFP...HAVE
BEEN UPDATED.
UPDATE ISSUED AT 723 AM EDT FRI AUG 16 2013
UPDATED THE FORECAST TO BETTER REFLECT CURRENT CONDITIONS AND MODEL
TRENDS. ONLY HAD TO MAKE MINOR TWEAKS TO THE TEMPERATURES AND DEW
POINTS. THE REST OF THE FORECAST IS ON TRACK.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 225 AM EDT FRI AUG 16 2013
THIS HAS BEEN AN UNUSUAL SUMMER AS IT HAS BE DOMINATED BY A UPPER LOW
OVER THE EASTERN PORTION OF THE US AND THE MODELS ARE ONCE AGAIN
BUILDING ANOTHER UPPER LOW IN OVER SOUTHERN ILLINOIS BY THIS EVENING.
WITH THIS TYPE OF PATTERN...THE POSITION OF THE UPPER LOW WILL BE
CRUCIAL AND WILL MAKE A BIG DIFFERENCE IN FORECAST. THE FORECAST IS
ALSO DIFFICULT DUE TO THE LACK OF ANY STRONG ORGANIZED SYSTEMS. THE
WEATHER WILL TEND TO BE DIURNALLY DRIVEN WITH THE BEST CHANCE FOR
CONVECTION BEING INTO THE AFTERNOON AND EARLY EVENING. WILL HAVE TO
WATCH FOR WEAK DISTURBANCES THAT WILL BE ROTATING AROUND THE LOW AND
WILL BE ABLE TO FOCUS SOME ENHANCED ACTIVITY. AT THIS POINT IN
TIME...CONFIDENCE IS LOW THAT THE MODELS WILL HAVE A GOOD HANDLE ON
THIS YET. FOR TODAY...KEPT THE PRECIPITATION MOSTLY WEST OF I 75 AS
ONLY A PORTION OF THE SYSTEM WILL BE ABLE TO INFLUENCE THE AREA.
THERE IS A MARKED DIFFERENCE IN THE NAM BUFFER SOUNDING FOR LONDON AND
JACKSON. AT JACKSON...THERE IS A PERSISTENT CAP IN PLACE THAT SHOULD
BE ABLE TO SUPPRESS THE CONVECTION THIS AFTERNOON. AT LONDON...THE
CAP DISAPPEARS AFTER 2 PM. FOR TEMPERATURES...WENT WITH THE BLEND AS
THERE IS ACTUALLY QUITE A BIT OF SPREAD BETWEEN THE VARIOUS MODELS.
WHEN THIS OCCURS AND ONE OF THE SOLUTIONS DOES NOT STAND OUT...LIKE
TO GO WITH THE BLEND.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 300 AM EDT FRI AUG 16 2013
THE MODELS WERE IN DECENT AGREEMENT WITH THE OVERALL LARGE SCALE
WEATHER PATTERN IN THE EXTENDED. A PASSING LARGE SCALE UPPER TROUGH
IS EXPECTED TO COMBINE WITH LOW LEVEL MOIST FLOW OFF THE SOUTHWESTERN
ATLANTIC. SOUTHEASTERLY FLOW AROUND THE WESTERN PERIPHERY OF THE
BERMUDA HIGH WILL PROVIDE THE WARM MOIST AIR TO THE REGION. SCATTERED
SHOWERS AND STORMS ARE PROGGED TO FORM MAINLY DURING THE AFTERNOON
AND EVENING HOURS ACROSS CENTRAL AND EASTERN KENTUCKY DURING PEAK
HEATING. THE ACTIVITY IS EXPECTED TO TAPER OFF AFTER SUNSET EACH
DAY...WITH DRY OVERNIGHT PERIODS AND MOSTLY DRY EARLY MORNING PERIODS.
HIGH TEMPERATURES THE FIRST FEW DAYS OF THE PERIOD SHOULD BE COOLER
THAN NORMAL...WITH WIDESPREAD CLOUD COVER AND PRECIPITATION IN THE
FORECAST. HIGHS ON SUNDAY AND MONDAY WILL TOP OUT AROUND 80 DEGREES.
FROM WEDNESDAY ONWARD SHOULD TOP OUT AT OR ABOVE NORMAL...WITH
READINGS IN THE MID TO UPPER 80S EACH DAY UNDER A SOUTHERLY FLOW
REGIME AND PARTLY CLOUDY SKIES. OVERNIGHT LOWS WILL DROP INTO THE
60S...WHICH IS NORMAL FOR THIS TIME OF YEAR.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 723 AM EDT FRI AUG 16 2013
HIGH PRESSURE OVER THE OHIO VALLEY WILL KEEP MOSTLY VFR CONDITIONS
ACROSS THE FORECAST AREA THROUGH SATURDAY. THERE WAS NOT ANY FOG AT
THE TAF SITES THIS MORNING AND ALTHOUGH WE DO EXPECT SOME MVFR
VISIBILITY IN FOG AROUND DAYBREAK SATURDAY IN MANY OF OUR VALLEY
LOCATIONS THE FLOW FROM THE NORTHEAST IS NOT CONDUCIVE FOR FOG OR
FOG ADVECTION AT OUR TAF SITES. THIS AFTERNOON...THERE MAY BE SOME
CONVECTION WEST OF A LINE FROM PULASKI TO BELL COUNTIES. PUT SOME
VCSH AT SME...BUT NOT AT LONDON AS THE SYSTEM SHOULD STAY TO THE
WEST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...JJ
LONG TERM...AR
AVIATION...JJ
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
149 PM EDT FRI AUG 16 2013
.UPDATE...
ISSUED AT 922 AM EDT FRI AUG 16 2013
PESKY PATCH OF MID CLOUDS/ISOLD SHRA OVER SCNTRL LK SUPERIOR LED TO
UPDATE FOR CNTRL CWA FOR THE AFTN. SPC MESOANALYSIS SHOWS SHRA ARE
IN AREA OF H7 MOISTURE CONVERGENCE AND WEAK ELEVATED CAPE. WV LOOP
SHOWS A HINT OF A WAVE AS WELL. THAT FEATURE SHOULD REMAIN IN TACT
AS IT DRIFTS ACROSS ECNTRL UPR MICHIGAN /P53 TO ERY/ THIS AFTN. THIS
WILL ALSO MATCH UP WITH PEAK HEATING. CONVECTIVE TEMPS IN THE UPR
70S TO LOWER 80S SUGGEST EVEN WITH ADDITIONAL MOISTURE AND FORCING
THAT SHRA COVERAGE WILL REMAIN MINIMAL AND LATEST RAP SOUNDINGS
INDICATE DRY AIR BLO CLOUD BASE. PUT A MENTION OF SPRINKLES IN FROM
ALGER TO LUCE COUNTIES THIS AFTN AS CU DECK EXPANDS WITH ADDITIONAL
MOISTURE. ELSEWHERE CU SHOULD STAY CAPPED AND NUDGED MAX TEMPS UP A
FEW DEGREES BASED ON 12Z RAOBS FM INL/GRB. MOST AREAS OVER INTERIOR
WEST HALF OF CWA SHOULD SEE TEMPS TOP OUT AROUND 80 DEGREES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 432 AM EDT FRI AUG 16 2013
BATTLING TEMPORARY VIS RESTRICTIONS AT A FEW OF THE SITES INLAND
FROM LAKE SUPERIOR THIS MORNING...AS IWD...IMT...ESC...AND ISQ JUMP
BETWEEN AROUND 1SM AND P6SM. HAVE KEPT PATCHY FOG GOING TO COVER
THIS...WITH A COUPLE POCKETS OF AREAS OF FOG NEAR THE LAKE MI
SHORELINE THROUGH DAYBREAK.
THE SFC RIDGE WILL REMAIN OVERHEAD...WITH THE HIGH STRENGTHENING
ACROSS THE NEW ENGLAND STATES THIS AFTERNOON THROUGH TONIGHT. LOW
PRESSURE WILL CONTINUE TO NEAR FROM THE W...WITH THE FIRST SFC LOW
ACROSS SASKATCHEWAN INTO N MANITOBA THIS MORNING SHIFTING E ABOUT
500MI BY 12Z SATURDAY /TO S MANITOBA AND S CENTRAL HUDSON BAY/.
WHILE THERE WILL BE WAA WITH 850MB TEMPS RISING FROM A CWA AVG OF
12C TO 13C BY THE END OF THE DAY IT WILL BE FAIRLY WEEK...AS NOTED
BY TRANSPORT WINDS OF 10KTS OR LESS OUT OF THE W TO SW...EVEN WITH
MIXING HEIGHTS OF 6-7.8KFT.
THE SW FLOW WILL PICK UP SLIGHT OVER W LAKE SUPERIOR OVERNIGHT
/AROUND 15KTS OR LESS/...WHILE REMAINING LIGHT OVER THE LAND.
CONTINUED TO GO AT OR BELOW GUIDANCE VALUES FOR OVERNIGHT LOWS GIVEN
OUR CLEAR SKY AND LIGHT WINDS...WITH UPPER 40S EXPECTED IN THE
TRADITIONAL COOL SPOTS WELL INLAND FROM THE GREAT LAKES.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 319 AM EDT FRI AUG 16 2013
MAIN FCST CONCERNS IN THE LONG TERM ARE TEMPS AND RELATIVELY SMALL
PCPN CHCS BEGINNING LATER ON SUN WITH PASSAGE OF DISTURBANCES IN
FAST W FLOW OVER SRN CANADA. ABOVE NORMAL HGTS ASSOCIATED WITH
SPRAWLING RDG OVER THE CONUS WL BRING ABV NORMAL TEMPS TO UPR MI
THIS WEEKEND AND NEXT WEEK.
SAT THRU SUN...CWA IS FCST TO BE DOMINATED BY DRY AIRMASS/ACYC WSW
FLOW ARND HI PRES CENTERED OVER THE NE CONUS. EXPECT MOCLR SKIES AND
A SLOW WARMING TREND WITH FCST H85 TEMPS 12-14C ON SAT AND THEN
14-16C ON SUN. STEADY SW WIND SHOULD HOLD MIN TEMPS UP ON SAT NGT...
ESPECIALLY IN THE DOWNSLOPE AREAS NEAR LK SUP FM IWD THRU THE
KEWEENAW TO BARAGA AND MQT.
SUN NGT/MON...LATEST LONGER RANGE GUIDANCE IN FAIRLY GOOD AGREEMENT
SHOWING A SHRTWV EMBEDDED IN THE WLY FLOW OVER SRN CANADA DIPPING
INTO THE UPR GRT LKS AND WEAKENING THE UPR RDG A BIT. THE GFS IS THE
MOST AGGRESSIVE MODEL TO WEAKEN THE RDG/GENERATE SHRA AND TS OVER
UPR MI. WL CARRY SOME LO CHC POPS OVER MAINLY THE NRN TIER OF THE
CWA CLOSER TO THE LOWER HGTS AND STNRY FNT FCST OVER SRN ONTARIO
JUST N OF LK SUP. MORE CLDS ARE LIKELY TO HOLD TEMPS UP A BIT MORE
ON SUN NGT BUT MAY CAUSE TEMPS TO RUN A BIT COOLER ON
MON...ESPECIALLY OVER THE NRN TIER.
EXTENDED...NOT SURPRISINGLY...EXTENDED MODEL GUIDANCE BEGINS TO SHOW
SOME DISAGREEMENT ON HOW MUCH THE UPR RDG WL BUILD BACK OVER THE UPR
LKS ON TUE FOLLOWING DEPARTURE OF SHRTWV RESPONSIBLE FOR SHRA/TS
POTENTIAL ON SUN NGT/MON AND THEN WHETHER/HOW QUICKLY MORE SHRTWVS
MIGHT IMPACT THE AREA AND FURTHER DEPRESS THE HIER HGTS OVER THE UPR
LKS AND TRY TO PUSH A STRONGER COLD FNT THRU UPR MI. CONSIDERING THE
LO PREDICTABILITY OF THESE DETAILS OF ZONAL FLOW REGIME IN THE
EXTENDED DURING SUMMER...FOLLOWED MODEL CONSENSUS FCST. OVERALL...
TEMPS SHOULD RUN ABV NORMAL...ESPECIALLY IF THE MODELS SHOWING THE
MORE PERSISTENT/STRONGER UPR RDG WITH NO FROPA THRU NEXT THU ARE
CORRECT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 148 PM EDT FRI AUG 16 2013
DAYTIME VFR CUMULUS CLOUDS AT KSAW AND KIWD THIS AFTN...BUT JUST
SOME MID CLOUDS AT TIMES FOR REST OF THE TAF PERIOD. LIGHT WINDS
WITH LAKE BREEZE DIRECTIONS THIS AFTN. EVENTUALLY A STEADY BUT LIGHT
SOUTHWEST WIND SETS UP ON SATURDAY BTWN A LOW PRESSURE TROUGH
MOVING ACROSS NORTHERN ONTARIO AND THE HIGH PRESSURE OVER THE LOWER
GREAT LAKES REGION.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 319 AM EDT FRI AUG 16 2013
OVERALL EXPECT WINDS LESS THAN 20 KTS THROUGH THE PERIOD AS HI
PRESSURE PERSISTS OVER THE GREAT LAKES REGION. THE ONE EXCEPTION
WILL BE SUN MORNING OVER THE NORTH CENTRAL...WHERE SW WINDS WILL
PEAK UP TO 25 KTS AHEAD OF A DISTURBANCE MOVING TOWARD THE UPPER
LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...JLA
SHORT TERM...KF
LONG TERM...KC
AVIATION...JLA
MARINE...KC
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1232 PM CDT FRI AUG 16 2013
.UPDATE...
ISSUED AT 501 AM CDT FRI AUG 16 2013
KUEX INDICATES SHOWER AND THUNDERSTORM ACTIVITY HAS DEVELOPED OVER
PORTIONS OF CENTRAL KANSAS...JUST SOUTH OF OUR CWA. RAP ANALYSIS
DATA INDICATES A SUBTLE MID LEVEL PERTURBATION IS ADVANCING SOUTH
FROM CENTRAL NEBRASKA INTO KANSAS...WITH WATER VAPOR IMAGERY ALSO
INDICATING A SUBTLE VORT MAX MOVING INTO KANSAS. BASED ON THE
POSITION OF THE SUBTLE VORT MAX ON WATER VAPOR IMAGERY...AND THE
POSITION OF THE MID LEVEL PERTURBATION FROM RAP ANALYSIS DATA...IT
APPEARS THE MID LEVEL TROUGH AXIS IS OVER OUR CWA NOW...WITH WEAK
MID LEVEL THERMAL ADVECTION AND DPVA AHEAD OF THIS TROUGH AXIS
LIKELY PROMOTING JUST ENOUGH OMEGA FOR PRECIPITATION PRODUCTION TO
OUR SOUTH. IN ADDITION TO THE MID LEVEL PERTURBATION...A SUBTLE
SURFACE TROUGH...PERHAPS A WEAK LOW LEVEL BAROCLINIC ZONE...IS
ALSO EVIDENT EXTENDING FROM WESTERN KANSAS INTO CENTRAL AND EAST-
CENTRAL KANSAS. RAP ANALYSIS SUGGESTS WEAK ISENTROPIC UPGLIDE IN
EXISTENCE ALONG/NEAR THE 295K SURFACE ACROSS THIS BOUNDARY...WITH
THE ONGOING SHOWER AND THUNDERSTORM ACTIVITY OCCURRING ALONG THIS
AXIS OF ISENTROPIC UPGLIDE. AT THIS TIME IT APPEARS THE WEAK MID
LEVEL OMEGA AND LOW LEVEL THERMAL ADVECTION RESPONSIBLE FOR THE
ONGOING PRECIPITATION PRODUCTION SHOULD REMAIN JUST SOUTH OF OUR
CWA...ALTHOUGH NOT BY MUCH...THUS ALLOWING FOR A CONTINUED DRY
FORECAST THROUGH THIS MORNING. THAT BEING SAID...THE ONGOING
SHOWER AND THUNDERSTORM ACTIVITY WILL NEED TO BE MONITORED TO MAKE
SURE IT DOES NOT SNEAK NORTHWARD INTO EXTREME SOUTHERN PORTIONS OF
OUR CWA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 331 AM CDT FRI AUG 16 2013
OVERNIGHT MAP ANALYSIS INDICATES A LONGWAVE MID TO UPPER LEVEL
TROUGH IN EXISTENCE ACROSS THE EASTERN HALF OF THE CONUS...AND A
RIDGE OVER THE WEST. MID TO UPPER LEVEL JET ENERGY EXTENDS FROM
THE NORTHWESTERN CONUS...NORTHEAST INTO SOUTHWESTERN CANADA...THEN
SOUTHEAST ACROSS THE CENTRAL CONUS...AND FINALLY EAST AND
EVENTUALLY NORTHEAST ACROSS PORTIONS OF THE SOUTHEASTERN CONUS AND
EVENTUALLY THE EAST/NORTHEASTERN CONUS. MID TO UPPER LEVEL FLOW
OVER THE CENTRAL PLAINS REMAINS FROM THE NORTHWEST AS A RESULT BUT
IS NOT PARTICULARLY STRONG...ONLY MAXING OUT AT AROUND 45KTS NEAR
200MB PER 00Z SOUNDING DATA FROM KLBF AND KOAX. THE AFOREMENTIONED
MID LEVEL LONGWAVE RIDGE AND TROUGH CAN ALSO BE SEEN ON WATER
VAPOR IMAGERY...WITH INCREASED VALUES OF MID LEVEL MOISTURE ALSO
NOTED FLOWING ALONG THE AFOREMENTIONED JET AXIS. AT THE SURFACE A
SUBTLE TROUGH IS NOTED EXTENDING FROM WESTERN KANSAS INTO PORTIONS
OF NORTHEASTERN KANSAS. THE LOW LEVEL WIND FIELD ACROSS OUR AREA
REMAINS FROM THE EAST/NORTHEAST AS A RESULT.
GUIDANCE FROM THE NAM...OPERATIONAL GFS...EC...AND SREF-MEAN ALL
SUGGEST THE WESTERN CONUS LONGWAVE TROUGH WILL DRIFT EAST SOMEWHAT
THROUGH THE NEXT 24 HOURS. THE RESULTANT LACK IN OVERALL KINEMATIC
FORCING SUGGESTS DRY CONDITIONS SHOULD BE OBSERVED ACROSS OUR AREA
TODAY AND TONIGHT. THE ONLY OPPORTUNITY FOR MEASURABLE
PRECIPITATION MAY BE ACROSS OUR SOUTHWEST 06-12Z SATURDAY AS WEAK
LOW LEVEL THERMAL ADVECTION ALONG THE AXIS OF ~30KT 850MB JET AXIS
PROMOTES ISOLATED TO SCATTERED SHOWER AND THUNDERSTORM ACTIVITY
OVER THE CENTRAL HIGH PLAINS. THERE IS AN OUTSIDE CHANCE SOME OF
THIS ACTIVITY COULD CREEP INTO OUR FAR SOUTHWESTERN CWA BUT AT
THIS TIME CONFIDENCE IS NOT HIGH ENOUGH TO INSERT POPS INTO THE
SHORT TERM FORECAST PERIOD AND AS A RESULT...DRY CONDITIONS ARE
CURRENTLY FORECAST THROUGH 12Z SATURDAY.
ALTHOUGH CONFIDENCE WITH RESPECT TO MEASURABLE PRECIPITATION BEING
REALIZED ACROSS OUR CWA IS VERY LOW...CONFIDENCE WITH RESPECT TO
INCREASING CLOUD COVER ACROSS OUR AREA TONIGHT INTO EARLY SATURDAY
IS INCREASING. GUIDANCE FROM THE NAM AND OPERATIONAL GFS...AS WELL
AS THE MET AND MAV...SUGGEST THE AFOREMENTIONED LOW LEVEL THERMAL
ADVECTION ALONG THE AXIS OF THE LOW LEVEL JET STREAK SHOULD BE
STRONG ENOUGH TO PROVIDE ISENTROPIC UPGLIDE AND
SATURATION...PRIMARILY ALONG THE 300-305K SURFACES. GIVEN THESE
SOLUTIONS...WENT AHEAD AND INCREASED CLOUD COVER SIGNIFICANTLY
ACROSS MUCH OF OUR CWA TONIGHT INTO EARLY SATURDAY MORNING. IN
ADDITION TO THE STRATUS...NEAR-ZERO LOW LEVEL DEW POINT
DEPRESSIONS AND A LIGHT SOUTHEAST LOW LEVEL WIND FIELD COULD ALSO
PROMOTE FOG DEVELOPMENT ACROSS PORTIONS OF THE CWA TOWARDS
DAYBREAK SATURDAY. GIVEN THIS POTENTIAL...WENT AHEAD AND INSERTED
PATCHY FOG INTO THE GRIDS FOR EARLY SATURDAY MORNING.
PERSISTENT CLOUD COVER THROUGH MID TO LATE THIS MORNING...ALONG
WITH A PERSISTENT EASTERLY COMPONENT TO THE LOW LEVEL WIND
FIELD...WILL LIKELY KEEP TEMPERATURES ON THE COOL SIDE TODAY.
GUIDANCE FROM THE MET...MAV...AND ECS ALL SEEM TO HAVE A GOOD
HANDLE ON THIS AND TAKING AN EVEN-AVERAGE OF THESE THREE SETS OF
GUIDANCE PROVIDES AFTERNOON HIGHS IN THE MID 70S ACROSS THE
NORTHEASTERN TWO-THIRDS OF OUR CWA...AND CLOSER TO 80 ACROSS OUR
SOUTHWEST. LITTLE CHANGE IN THE LOW LEVEL AIRMASS AND INCREASING
CLOUD COVER...MUCH LIKE WE ARE OBSERVING THIS MORNING...SHOULD
PROVIDE SIMILAR OVERNIGHT LOW TEMPERATURES TONIGHT WHEN COMPARED
TO EARLY THIS MORNING. GIVEN THIS...WENT AHEAD WITH EARLY SATURDAY
MORNING TEMPERATURES NEAR 60 FOR MOST LOCATIONS ACROSS THE CWA.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 331 AM CDT FRI AUG 16 2013
A PATTERN CHANGE APPEARS TO BE ON THE WAY THAT WILL RESULT IN
DRIER WX AND TEMPS MORE TYPICAL OF SUMMER. THE MID-SUMMER BREAK
FOR A/C UNITS WILL END AS MULTIPLE DAYS OF 90F HEAT ARE IN THE
OFFING.
ALOFT: NOW THAT THE AK-CANADA HIGH LATITUDE BLOCKING IS FINALLY
BREAKING DOWN...THE FAIRLY HIGH AMPLITUDE ROCKIES RIDGE/ERN USA
TROF COMBO THAT HAS DOMINATED THE WX FOR THE PAST TWO WEEKS WILL
DE-AMPLIFY AS WELL. THE WESTERLIES WILL BECOME ZONAL AGAIN OVER
CANADA AND THE NRN USA. MEANWHILE...THE TROF OVER THE E PAC WILL
CLOSE OFF AND BECOME CUT-OFF...LINGERING OVER CA FOR THE NEXT
SEVERAL DAYS. THIS COMBINED WITH THE ERN USA TROF LIFTING OUT WILL
ALLOW THE SUBTROPICAL HIGH TO EXPAND ACROSS MOST OF THE CONUS. THE
WARMER TEMPS ALOFT SHOULD PUT A CAP ON PCPN POTENTIAL FOR SEVERAL
DAYS.
SFC: EXPANSIVE HIGH PRES THAT HAS BEEN PARKED OVER THE OH VALLEY
WILL GRADUALLY REPOSITION ITSELF OVER THE WRN ATLANTIC...BUT IT
WILL STILL EXTEND BACK INTO THE ERN USA. AS A SERIES OF LOWS
TRACKS ACROSS CANADA...A LEE-SIDE TROF WILL DEVELOP. THE INCREASED
PRES GRADIENT WILL RESULT IN A BIT MORE WIND THAN WE/VE SEEN FOR
THE LAST COUPLE WEEKS. THE NEXT COOL FRONTAL PASSAGE IS ADVERTISED
FOR NEXT THU AFTN-NGT.
THE 00Z EC AND GFS LOOK NOTHING ALIKE AT THE SFC AT 168 HRS /00Z
FRI/. THE GFS HAS A STRONGER SHRTWV TROF OVER THE PAC NW /H5 HGTS
40-60 M LOWER/ WHICH RESULTS IN A 997 MB LOW OVER ND VS. THE EC
1019 MB HIGH OVER LAKE WINNIPEG. THE 18Z GFS WAS MORE SUPPORTIVE
OF THE EC SOLUTION. SO THE 00Z RUN WAS NOT FACTORED INTO THIS FCST
BEYOND TUE.
THE DAILY DETAILS...
SAT: WIDESPREAD LOW STRATUS APPEARS LIKELY VIA MODEL CROSS
SECTIONS. SINCE IT/S CURRENTLY IN-PLACE AND THE FCST AREA WILL
REMAIN ON THE WRN FRINGE OF A SIZABLE POOL OF COOL AIR IN THE LOW-
LVLS...IT WILL BE HARD TO GET RID OFF UNTIL THE THERMAL TROF
RELEASES ITS GRIP WHICH WILL PROBABLY HAPPEN SUN.
SO EXPECT A CLOUDY START MOST AREAS WITH SLOW BUT GRADUAL
IMPROVEMENT. THERE WILL PROBABLY BE SOME AREAS THAT DON/T
COMPLETELY CLEAR OUT UNTIL MID-LATE AFTN. CAN FORESEE PARTS OF THE
FCST AREA NOT REACHING 80F.
SAT NGT: THE PRES GRADIENT WILL KEEP WINDS 7-15 MPH. SO DON/T
ENVISION FOG BEING A PROBLEM...BUT GIVEN THAT THE STRATUS/HIGH
LOW-LVL MSTR MAY NOT COMPLETELY MIX OUT SAT AFTN...LOW CLOUDS
SHOULD REFORM. JUST NOT SURE TO WHAT EXTENT.
SUN: THE DAY MAY START WITH STRATUS COVERING ALL OR PART OF THE
FCST AREA. FCST SOUNDINGS SUGGEST DRIER AIR WILL MIX DOWN. SO
IMPROVEMENT SHOULD BE MORE PERMANENT. SHOULD BE AN ESPECIALLY NICE
DAY FOR OUTDOOR ACTIVITIES BUT WITH S WINDS GUSTING UP TO 25 MPH.
MON-WED: SUNNY AND DRY AS WE SEE IT NOW. HIGH TEMPS WILL AVERAGE
ABOUT 5F WARMER THAN NORMAL.
THE NEXT OPPORTUNITY FOR TSTMS IS SLATED FOR THU AFTN-EVNG WITH A
COOL FRONTAL PASSAGE. WITH SUCH A WARM LOOK TO THE HGTS ALOFT...
CAPPING WILL PROBABLY LIMIT COVERAGE TO JUST AN ISOLATED TSTM OR
TWO.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1226 PM CDT FRI AUG 16 2013
QUIET CONDITIONS ARE FORECAST FOR THIS TAF PERIOD...WITH PRIMARY
FORECAST CONCERNS LYING WITH SKY COVER AND VISIBILITY...MAINLY
LATE TOMORROW NIGHT/EARLY TOMORROW MORNING. CONTINUING TO SEE
STUBBORN STRATUS AFFECTING THE TERMINAL AREA...WITH VISIBLE
SATELLITE SHOWING THE LAYER TRYING TO BREAK UP. THINKING THAT THE
TERMINAL WILL SEE AT LEAST SOME SUN THIS AFTERNOON...BUT TIMING IS
DIFFICULT SO KEPT MVFR CONDITIONS GOING FOR ANOTHER COUPLE HRS. A
RETURN OF THE MORE WIDESPREAD STRATUS DECK IS EXPECTED
TONIGHT...WITH ANOTHER CHANCE FOR DIMINISHED VISIBILITIES...WITH A
RETURN OF MVFR CONDITIONS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...BRYANT
SHORT TERM...BRYANT
LONG TERM...HALBLAUB
AVIATION...ADO
AREA FORECAST DISCUSSION
NWS RALEIGH NC
230 PM EDT FRI AUG 16 2013
.SYNOPSIS...
SURFACE HIGH PRESSURE CENTERED OVER THE MID-ATLANTIC WILL EXTEND
SOUTHWARD INTO THE CAROLINAS THROUGH THE WEEKEND... AS WEAK WAVES OF
LOW PRESSURE DEVELOP ALONG A STALLED FRONT ACROSS THE DEEP SOUTH AND
SOUTHEAST COAST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1015 AM FRIDAY...
A 1022MB SURFACE HIGH OVER PA/MD EXTENDS SOUTH INTO THE CAROLINAS
THIS MORNING...WITH A STATIONARY FRONT DRAPED ACROSS COASTAL SC AND
GEORGIA IN A CAD-LIKE PATTERN. ALOFT...AND UPPER JET STREAK
EJECTING OUT OF THE BASE OF THE LW TROUGH IS EVIDENT IN WATER VAPOR
IMAGERY OVER NORTHERN GEORGIA. IN RESPONSE...WIDESPREAD PRECIP HAS
BROKEN OUT OVER THE WESTERN HALF OF SC...BUT IS STRUGGLING TO MOVE
NORTH OF THE 925-850MB FRONTAL ZONE...WHICH IS LOCATED NEAR THE
NC/SC BORDER. MID/HIGH CLOUDS ARE POURING INTO THE CWA FROM THE
SOUTHWEST...BUT UNTIL THE 850MB FRONT BEGINS TO PUSH NORTH...WHICH
WILL HAPPEN ONLY SLOWLY BETWEEN NOW AND 00Z THIS EVENING...PRECIP
WILL CONTINUE TO STRUGGLE TO MOVE INTO THE DRY AIR RIDGE.. WITH
SUPPORT FROM HRRR AND OTHER HI-RES WRF MODELS...EXPECT PRECIP TO
SPREAD MORE EAST THAN NORTH ALONG THE BETTER LOW-LEVEL FORCING
THROUGH EARLY AFTERNOON. HAVE REMOVED POPS FROM THE NORTHERN
PIEDMONT AND NORTHERN COASTAL PLAIN...WITH A VERY TIGHT GRADIENT
NEAR THE HWY 64 CORRIDOR AND CATEGORICAL POPS NEAR THE SC BORDER
WILL MAKE SOME SMALL ADJUSTMENTS TO HIGHS BASED ON THE LACK OF
PRECIP FOR MOST OF THE CWA...BUT INCREASING CLOUD COVER WILL STILL
TEMPER HEATING AND THE PREVIOUS FORECAST APPEARS TO BE MOSTLY IN
TRACK. HIGHS IN THE UPPER 60S IN THE SOUTHWEST AND UPPER 70S IN
THE NORTHEAST. -SMITH
TONIGHT...A STRONGER MID-UPPER LEVEL S/W SEEN ON WATER VAPOR IMAGERY
DIVING SWD ACROSS THE CENTRAL PLAINS THIS MORNING WILL DIG INTO THE
BOTTOM OF THE L/W TROUGH....BACKING OUR MID-UPPER LEVEL FLOW TO A
MORE SWLY DIRECTION. IN ADDITION THIS FEATURE WILL ENHANCE THE SLY
FLOW A FEW THOUSAND FEET ABOVE THE SURFACE...INCREASING ISENTROPIC
LIFT. THIS WILL LEAD TO RAIN/RAIN SHOWERS BECOMING WIDESPREAD AND
INCREASE IN INTENSITY ACROSS CENTRAL NC TONIGHT. HAVE INCREASED POPS
TO CATEGORICAL OVER THE SW TWO-THIRDS OF THE FORECAST AREA WITH
LIKELY POPS OVER THE NE. MIN TEMPS LOWER 60S NW TO THE UPPER 60S SE.
&&
.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 AM FRIDAY...
SATURDAY...THE RAIN OVERNIGHT WILL LOCK IN A HYBRID COLD AIR DAMMING
AIR MASS ACROSS THE PIEDMONT. CONTINUED ISENTROPIC LIFT IN
CONJUNCTION OF THE AREA OF LOW PRESSURE OVER THE LOWER MS VALLEY
WILL CAUSE WIDESPREAD LOW CLOUDS AND PERSISTENT RAIN. THIS WILL
RESULT IN A DIURNAL TEMP RECOVERY OF NO MORE THAN 4-5 DEGREES ACROSS
THE NW PIEDMONT...AND 5-7 DEGREES ACROSS THE REMAINDER OF THE
PIEDMONT AND COASTAL PLAIN. MAX TEMPS MID-UPPER 60S NW TO MID-UPPER
70S FAR SE.
HAVE INCREASED POPS TO CATEGORICAL SATURDAY AND LOWERED
MAX TEMPS A DEGREE OR TWO FROM THE PREVIOUS FORECAST. WHILE RAIN
WILL OCCUR FOR MOST OF THE DAY...NOT ANTICIPATING AMOUNTS THAT WOULD
WARRANT THE ISSUANCE OF A FLASH FLOOD WATCH. THAT BEING SAID...WHERE
POCKETS OF MODERATE RAINFALL DUE SET-UP...RAINFALL RATES OF A THIRD
TO A HALF INCH PER HOUR FOR A FEW HOURS WILL CAUSE EXTENSIVE PONDING
OF WATER AND NUISANCE FLOODING OF POOR DRAINAGE AREAS.
SATURDAY NIGHT...CONTINUED SW FLOW ALOFT WITH EMBEDDED DISTURBANCES
INTERACTING WITH THE MOISTURE RICH AIR MASS AND CONTINUED LOW LEVEL
OVERRUNNING WILL MAINTAIN HIGHER THAN NORMAL POPS ACROSS CENTRAL NC.
EXPECT LIKELY POPS TO SUFFICE BUT WOULD NOT BE SURPRISED IF
CATEGORICAL POPS NEEDED IN LATER FORECAST ISSUANCE. TEMPS WILL HOLD
STEADY OR ONLY LOWER A FEW DEGREES FROM OBSERVED HIGH TEMPS ON
SATURDAY. MAY SEE WIDESPREAD AREAS OF FOG DEVELOP OVERNIGHT...
ESPECIALLY ACROSS THE PIEDMONT. MIN TEMPS LOW-MID 60S PIEDMONT TO
THE UPPER 60S IN THE COASTAL PLAIN AND SANDHILLS.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 230 PM FRIDAY...
THE LONG TERM PERIOD OF THE FORECAST FEATURES AN UNSETTLED PATTERN
WITH A WETTER THAN NORMAL ATMOSPHERE AND GREATER THAN TYPICAL
UNCERTAINTY IN FORECAST DETAILS.
THE CLOSED UPPER TROUGH OVER THE MID MISSISSIPPI VALLEY ON SUNDAY
OPENS UP AND LIFTS OUT ACROSS THE MID ATLANTIC REGION ON MONDAY. A
SURGE OF ISENTROPIC LIFT MOVES ACROSS THE NC/VA EARLY SUNDAY AHEAD
OF THE EXITING TROUGH RESULTING IN HIGH POPS. A LINGERING COLD AIR
DAMMING AIR MASS IS EXPECTED ACROSS THE INTERIOR PIEDMONT FOR SUNDAY
INTO MONDAY WITH WEAK FORCING AND WIDELY SCATTERED POPS.
HEIGHTS BEGIN TO RISE SLIGHTLY ON MONDAY INTO TUESDAY AS THE
SUBTROPICAL RIDGE ADVANCES WEST BUT AN AXIS OF HIGHER PRECIPITABLE
WATER LINGERS ACROSS THE SOUTHERN CAROLINAS DURING THE PERIOD.
PREDICTABILITY IS LOW BUT BOTH THE GFS/ECMWF SUGGEST A WEAK SURFACE
TROUGH IS LIKELY TO BE LINGERING SOMEWHERE ACROSS SOUTHERN PORTIONS
OF THE REGION SUGGESTING THAT POPS ON TUESDAY AND WEDNESDAY SHOULD
BE LOWER THAN PREVIOUS DAYS AND GREATEST IN THE SOUTHERN PORTIONS OF
THE FORECAST AREA.
LATER IN THE PERIOD GUIDANCE HAS TRENDED TOWARD A REDEVELOPMENT OF
THE EASTERN CONUS TROUGH IN PART RESULTING FROM A SOUTHWARD SHIFT OF
THE WESTERLIES IN SOUTHERN CANADA ON THURSDAY INTO FRIDAY. THE
RESULT IS AN INCREASE IN DEEP LAYER MOISTURE AND LOWERING HEIGHTS
ACROSS THE CAROLINAS LATE IN THE WORK WEEK WITH A TENDENCY FOR
SCATTERED AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS...ESPECIALLY ACROSS SOUTHERN AND EASTERN PORTIONS OF
THE FORECAST AREA.
A LINGERING COLD AIR DAMMING TEMPERATURE REGIME IS EXPECTED ON
SUNDAY AND INTO MONDAY WITH LIMITED DIURNAL RANGE AND MUCH BELOW
NORMAL MAX TEMPERATURES ACROSS THE NORTHWEST PIEDMONT. TEMPERATURES
IN GENERAL WILL MODERATE AND WARM TO AROUND SEASONABLE MAX
TEMPERATURES FOR WEDNESDAY THROUGH FRIDAY WITH SLIGHTLY ABOVE
AVERAGE MINIMUM TEMPERATURES. -BLAES
&&
.AVIATION /18Z FRIDAY THROUGH TUESDAY/...
AS OF 145 PM FRIDAY...
AN EXPANDING AREA OF LIGHT TO MODERATE RAIN OVER SC IS MOVING INTO
THE SOUTHERN PORTIONS OF NC...THOUGH VFR CONDITIONS ARE STILL
OBSERVED AT ALL TAF SITES. THIS PRECIP...AND CORRESPONDING LOWERING
OF CEILINGS...IS EXPECTED TO SPREAD FROM KFAY TO KRWI THIS
AFTERNOON..WITH KRDU LIKELY JUST ON THE EDGE OF THE RAIN SHIELD AND
SUB-VFR CONDITIONS. ANOTHER...MORE WIDESPREAD ROUND OF PRECIP IS
EXPECTED TO MOVE INTO CENTRAL NC FROM THE OVERNIGHT AND CONTINUE
DURING THE DAY SATURDAY. MOST MODELS INDICATE MVFR CEILINGS WILL
DEVELOP IN THE KFAY AREA BY 00Z THIS EVENING...LOWERING TO IFR AFTER
MIDNIGHT. FURTHER NORTH...MVFR CEILINGS WILL BE DELAYED...BUT A
GENERAL LOWER TO IFR LEVELS IS EXPECTED BY SATURDAY MORNING. THERE
IS MEDIUM TO HIGH CONFIDENCE IN THE POOR AVIATION CONDITIONS DURING
THE CURRENT TAF PERIOD.
OUTLOOK...
WIDESPREAD RAIN WILL CONTINUE INTO SATURDAY NIGHT..WITH IMPROVEMENT
EXPECTED FROM SOUTH TO NORTH BY SUNDAY. HOWEVER...SUB-VFR
CONDITIONS WILL LIKELY PERSIST THROUGH SUNDAY AND EVEN INTO MONDAY
IN THE TRIAD AREA.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BADGETT
NEAR TERM...WSS/SMITH
SHORT TERM...WSS
LONG TERM...BLAES
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
145 PM EDT FRI AUG 16 2013
.SYNOPSIS...
SURFACE HIGH PRESSURE CENTERED OVER THE MID-ATLANTIC WILL EXTEND
SOUTHWARD INTO THE CAROLINAS THROUGH THE WEEKEND... AS WEAK WAVES OF
LOW PRESSURE DEVELOP ALONG A STALLED FRONT ACROSS THE DEEP SOUTH AND
SOUTHEAST COAST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1015 AM FRIDAY...
A 1022MB SURFACE HIGH OVER PA/MD EXTENDS SOUTH INTO THE CAROLINAS
THIS MORNING...WITH A STATIONARY FRONT DRAPED ACROSS COASTAL SC AND
GEORGIA IN A CAD-LIKE PATTERN. ALOFT...AND UPPER JET STREAK
EJECTING OUT OF THE BASE OF THE LW TROUGH IS EVIDENT IN WATER VAPOR
IMAGERY OVER NORTHERN GEORGIA. IN RESPONSE...WIDESPREAD PRECIP HAS
BROKEN OUT OVER THE WESTERN HALF OF SC...BUT IS STRUGGLING TO MOVE
NORTH OF THE 925-850MB FRONTAL ZONE...WHICH IS LOCATED NEAR THE
NC/SC BORDER. MID/HIGH CLOUDS ARE POURING INTO THE CWA FROM THE
SOUTHWEST...BUT UNTIL THE 850MB FRONT BEGINS TO PUSH NORTH...WHICH
WILL HAPPEN ONLY SLOWLY BETWEEN NOW AND 00Z THIS EVENING...PRECIP
WILL CONTINUE TO STRUGGLE TO MOVE INTO THE DRY AIR RIDGE.. WITH
SUPPORT FROM HRRR AND OTHER HI-RES WRF MODELS...EXPECT PRECIP TO
SPREAD MORE EAST THAN NORTH ALONG THE BETTER LOW-LEVEL FORCING
THROUGH EARLY AFTERNOON. HAVE REMOVED POPS FROM THE NORTHERN
PIEDMONT AND NORTHERN COASTAL PLAIN...WITH A VERY TIGHT GRADIENT
NEAR THE HWY 64 CORRIDOR AND CATEGORICAL POPS NEAR THE SC BORDER
WILL MAKE SOME SMALL ADJUSTMENTS TO HIGHS BASED ON THE LACK OF
PRECIP FOR MOST OF THE CWA...BUT INCREASING CLOUD COVER WILL STILL
TEMPER HEATING AND THE PREVIOUS FORECAST APPEARS TO BE MOSTLY IN
TRACK. HIGHS IN THE UPPER 60S IN THE SOUTHWEST AND UPPER 70S IN
THE NORTHEAST. -SMITH
TONIGHT...A STRONGER MID-UPPER LEVEL S/W SEEN ON WATER VAPOR IMAGERY
DIVING SWD ACROSS THE CENTRAL PLAINS THIS MORNING WILL DIG INTO THE
BOTTOM OF THE L/W TROUGH....BACKING OUR MID-UPPER LEVEL FLOW TO A
MORE SWLY DIRECTION. IN ADDITION THIS FEATURE WILL ENHANCE THE SLY
FLOW A FEW THOUSAND FEET ABOVE THE SURFACE...INCREASING ISENTROPIC
LIFT. THIS WILL LEAD TO RAIN/RAIN SHOWERS BECOMING WIDESPREAD AND
INCREASE IN INTENSITY ACROSS CENTRAL NC TONIGHT. HAVE INCREASED POPS
TO CATEGORICAL OVER THE SW TWO-THIRDS OF THE FORECAST AREA WITH
LIKELY POPS OVER THE NE. MIN TEMPS LOWER 60S NW TO THE UPPER 60S SE.
&&
.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 AM FRIDAY...
SATURDAY...THE RAIN OVERNIGHT WILL LOCK IN A HYBRID COLD AIR DAMMING
AIR MASS ACROSS THE PIEDMONT. CONTINUED ISENTROPIC LIFT IN
CONJUNCTION OF THE AREA OF LOW PRESSURE OVER THE LOWER MS VALLEY
WILL CAUSE WIDESPREAD LOW CLOUDS AND PERSISTENT RAIN. THIS WILL
RESULT IN A DIURNAL TEMP RECOVERY OF NO MORE THAN 4-5 DEGREES ACROSS
THE NW PIEDMONT...AND 5-7 DEGREES ACROSS THE REMAINDER OF THE
PIEDMONT AND COASTAL PLAIN. MAX TEMPS MID-UPPER 60S NW TO MID-UPPER
70S FAR SE.
HAVE INCREASED POPS TO CATEGORICAL SATURDAY AND LOWERED
MAX TEMPS A DEGREE OR TWO FROM THE PREVIOUS FORECAST. WHILE RAIN
WILL OCCUR FOR MOST OF THE DAY...NOT ANTICIPATING AMOUNTS THAT WOULD
WARRANT THE ISSUANCE OF A FLASH FLOOD WATCH. THAT BEING SAID...WHERE
POCKETS OF MODERATE RAINFALL DUE SET-UP...RAINFALL RATES OF A THIRD
TO A HALF INCH PER HOUR FOR A FEW HOURS WILL CAUSE EXTENSIVE PONDING
OF WATER AND NUISANCE FLOODING OF POOR DRAINAGE AREAS.
SATURDAY NIGHT...CONTINUED SW FLOW ALOFT WITH EMBEDDED DISTURBANCES
INTERACTING WITH THE MOISTURE RICH AIR MASS AND CONTINUED LOW LEVEL
OVERRUNNING WILL MAINTAIN HIGHER THAN NORMAL POPS ACROSS CENTRAL NC.
EXPECT LIKELY POPS TO SUFFICE BUT WOULD NOT BE SURPRISED IF
CATEGORICAL POPS NEEDED IN LATER FORECAST ISSUANCE. TEMPS WILL HOLD
STEADY OR ONLY LOWER A FEW DEGREES FROM OBSERVED HIGH TEMPS ON
SATURDAY. MAY SEE WIDESPREAD AREAS OF FOG DEVELOP OVERNIGHT...
ESPECIALLY ACROSS THE PIEDMONT. MIN TEMPS LOW-MID 60S PIEDMONT TO
THE UPPER 60S IN THE COASTAL PLAIN AND SANDHILLS.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 300 AM FRIDAY...
THE MEDIUM RANGE PORTION OF THE FORECAST WILL TRANSITION FROM A WARM
SEASON CAD EVENT OVER THIS WEEKEND TO MORE TYPICAL AFTERNOON AND
EVENING SCATTERED SHOWERS AND STORMS PATTERN AND NEAR NEAR NORMAL
TEMPS BY NEXT WEEK
SUNDAY AND SUNDAY NIGHT:
THE PRIMARY SURFACE LOW ASSOCIATED WITH THE SYSTEM MENTIONED IN THE
NEAR/SHORT TERM PARTS OF THE FORECAST IS EXPECTED TO LIFT
NORTHEASTWARD FROM THE NC COAST SUNDAY MORNING TO OFF THE
VA/MID-ATLANTIC COAST BY SUNDAY AFTERNOON/EVENING. HOWEVER... MOST
GUIDANCE SHOWS CONTINUED GOOD CHANCES FOR PRECIP ACROSS OUR
NORTHWEST/WEST ASSOCIATED WITH WEAK ISENTROPIC UPGLIDE AND A
POSSIBLE IMPULSE ALOFT MOVING THROUGH THE SOUTH-SOUTHWESTERLY FLOW.
HOWEVER... PRECIP AMOUNTS ARE EXPECTED TO BE LIGHTER THAN ON
SATURDAY. FOR LOCATIONS ACROSS THE NORTHWEST/WEST WHERE THE CAD WILL
HOLD... EXPECT AN OVERCAST... DAMP/WET... COOL DAY. FURTHER EAST AND
SOUTHEAST ACROSS OUR COASTAL PLAIN AND EASTERN SANDHILL COUNTIES
EXPECT WE WILL SEE MORE ISOLATED TO SCATTERED ACTIVITY ON SUNDAY. WE
WILL SEE THE COASTAL FRONT REMAIN TO THE EAST OF THE AREA STILL.
HOWEVER... THE CAD BOUNDARY MAY RETREAT TO THE WEST OF THIS AREA. IF
WE DO SEE A FEW BREAKS IN THE CLOUDS BY AFTERNOON WE MAY SEE SOME
INSTABILITY DEVELOP... RESULTING IN A CHANCE OF SOME SHOWERS AND
EVEN SOME STORMS. FOR NOW WILL GO WITH CHANCE POPS FOR ALL DAY
SUNDAY HERE... WITH THE MAIN THREAT FOR ANY STORMS EXPECTED IN THE
AFTERNOON. FOR LOCATIONS THAT DO SEE THE CAD BOUNDARY RETREAT WE
WILL SEE TEMPS WARM UP SOME... BUT STILL BELOW SEASONAL NORMS.
EXPECT HIGHS SUNDAY WILL RANGE FROM THE LOWER 70S NW TO LOWER 80S TO
MAYBE EVEN MID 80S SE.
WILL CONTINUE TO ADVERTISE A CHANCE OF SHOWERS/RAIN ON SUNDAY NIGHT
ACROSS THE AREA. HOWEVER... THE TROUGH ALOFT CENTERED TO OUR WEST
ACROSS THE OH/TN VALLEY WILL WEAKEN AND BEGIN LIFTING NORTHEASTWARD.
LOW TEMPS MONDAY MORNING ARE EXPECTED TO BE IN THE 66-71 DEGREE
RANGE IN A NW TO SE FASHION.
MONDAY THROUGH THURSDAY:
THE TROUGH ALOFT MENTIONED ABOVE WILL CONTINUE TO WEAKEN AS IT
SLOWLY LIFT NORTHEASTWARD EARN NEXT WEEK. HOWEVER... MEDIUM RANGE
MODEL GUIDANCE HAS BEEN HINTING AT THE POSSIBILITY OF THE WEAKENING
SHEAR-AXIS LINGERING ACROSS THE AREA. GIVEN THE EXPECTED LINGERING
MOIST LOW LEVEL AIRMASS OVER OUR REGION AND PW`S GENERALLY RANGING
FROM 1.5 TO 2.0 INCHES EXPECT WE WILL SEE AT LEAST ISOLATED TO
SCATTERED AFTERNOON/EVENING CONVECTION EACH DAY... ESPECIALLY ON
MONDAY AND TUESDAY... WITH THE POTENTIAL FOR A LINGERING CAD
BOUNDARY ON MONDAY. THIS PATTERN WILL YIELD A TRANSITION BACK TO
NEAR NORMAL TEMPS BY MID/LATE WEEK AND A MORE TYPICAL SUMMERTIME
WEATHER.
&&
.AVIATION /18Z FRIDAY THROUGH TUESDAY/...
AS OF 145 PM FRIDAY...
AN EXPANDING AREA OF LIGHT TO MODERATE RAIN OVER SC IS MOVING INTO
THE SOUTHERN PORTIONS OF NC...THOUGH VFR CONDITIONS ARE STILL
OBSERVED AT ALL TAF SITES. THIS PRECIP...AND CORRESPONDING LOWERING
OF CEILINGS...IS EXPECTED TO SPREAD FROM KFAY TO KRWI THIS
AFTERNOON..WITH KRDU LIKELY JUST ON THE EDGE OF THE RAIN SHIELD AND
SUB-VFR CONDITIONS. ANOTHER...MORE WIDESPREAD ROUND OF PRECIP IS
EXPECTED TO MOVE INTO CENTRAL NC FROM THE OVERNIGHT AND CONTINUE
DURING THE DAY SATURDAY. MOST MODELS INDICATE MVFR CEILINGS WILL
DEVELOP IN THE KFAY AREA BY 00Z THIS EVENING...LOWERING TO IFR AFTER
MIDNIGHT. FURTHER NORTH...MVFR CEILINGS WILL BE DELAYED...BUT A
GENERAL LOWER TO IFR LEVELS IS EXPECTED BY SATURDAY MORNING. THERE
IS MEDIUM TO HIGH CONFIDENCE IN THE POOR AVIATION CONDITIONS DURING
THE CURRENT TAF PERIOD.
OUTLOOK...
WIDESPREAD RAIN WILL CONTINUE INTO SATURDAY NIGHT..WITH IMPROVEMENT
EXPECTED FROM SOUTH TO NORTH BY SUNDAY. HOWEVER...SUB-VFR
CONDITIONS WILL LIKELY PERSIST THROUGH SUNDAY AND EVEN INTO MONDAY
IN THE TRIAD AREA.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BADGETT
NEAR TERM...WSS/SMITH
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
129 PM CDT FRI AUG 16 2013
.UPDATE...FOR 18Z TAFS...
&&
.AVIATION...
AN UPPER LOW IS FORECAST TO SITUATE ITSELF OVER WESTERN TN DURING THE
NEXT 24 HOURS KEEPING BKN TO OVC SKIES FOR ALL SITES THROUGH
TOMORROW. INCLUDED A TEMPO FOR LIGHT FOG IN THE EARLY MORNING
HOURS OF SATURDAY. PRECIP CHANCES INCREASE DURING THE DAY ON
SATURDAY...JUST INCLUDED VCSH AT BNA WHERE MOISTURE LOOKS BEST
AFTER 12Z.
&&
.PREV DISCUSSION... /ISSUED 932 AM CDT FRI AUG 16 2013/
UPDATE...
CLOUDS IN PLACE THIS MORNING. UPPER LEVEL TROUGH EXPECTED TO
BEGIN STRENGTHENING TODAY. 18Z PROGS SHOW CAPPING IN PLACE BUT
MOISTURE LEVELS ARE ON THE INCREASE. WEAK SFC TROUGH WILL STRETCH
FROM NRN MS THROUGH MIDDLE TN THIS AFTERNOON. THIS WILL SERVE AS
SOME WEAK FORCING WHICH MAY SPAWN SOME SHOWER ACTIVITY TODAY.
LATEST HRRR STILL IN SUPPORT OF SOME SHOWER DEVELOPMENT. HOWEVER...ANY
ACTIVITY SHOULD REMAIN ON THE LIGHT SIDE.
FOR THE FORECAST...CANNOT SEE A REASON TO CHANGE ANYTHING AT THIS
TIME. THE 18Z TEMPS PROG APPEARS TO BE IN LINE WITH THE CURRENT
FORECAST MAXES. INSTABILITY IS QUITE WEAK SO WILL CONTINUE WITH
JUST A SLIGHT CHANCE OF THUNDER.
PREV DISCUSSION... /ISSUED 641 AM CDT FRI AUG 16 2013/
UPDATE...FOR 12Z AVIATION FORECASTS.
AVIATION...EXPECT VFR CIGS THROUGHOUT THE TAF PERIOD. DESPITE
CIGS...HOWEVER...SOME VIS RESTRICTIONS ARE LIKELY OVERNIGHT AT
CKV/CSV DUE TO PATCHY FOG. SCATTERED -SHRA/-TSRA ARE EXPECTED TO
OCCUR, ESPECIALLY IN THE AFTERNOON AND EVENING. HOWEVER, WOULD BE
HARD PRESSED TO DETERMINE IF OR WHEN A -SHRA/-TSRA MIGHT AFFECT
ANY PARTICULAR TERMINAL. THUS, WILL LEAVE MENTION OF PRECIP OUT OF
TAFS FOR NOW. LIGHT EAST-T0-NORTHEAST WINDS ARE ANTICIPATED
THROUGHOUT THE TAF PERIOD.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
11
AREA FORECAST DISCUSSION...CORRECTION
NWS SAN ANGELO TX
336 PM CDT FRI AUG 16 2013
.SHORT TERM...
/Tonight and Tomorrow/
Visible satellite imagery shows sunny skies across West Central
Texas this afternoon. The latest mesoanalysis indicates a stable
environment over our area, with an instability axis across South and
far West Texas.
The models, including the 3KM HRRR model develop scattered
thunderstorms over Eastern New Mexico and far West Texas in the
instability axis during the late afternoon and evening. Upper level
northerly flow will keep this activity west of our area for tonight.
Lows will be in the mid 60s to lower 70s.
Going with a dry forecast for Saturday across the area. Isolated
thunderstorms will probably fire to our west during the afternoon
hours. The upper level northerly flow should keep the storms west of
our area. Highs will be in the lower to mid 90s.
.LONG TERM...
/Saturday Night through Friday/
The upper level flow will be north to northeast next week as a high
pressure ridge sets up from the Southern Rockies into the Central
Plains. Basically a normal summertime pattern with little upper
level and mesoscale forcing. Temperatures will be near or slightly
above seasonable normals. Highs will be in the 90s with lows in the
upper 60s to lower 70s. Going with a dry forecast through the
extended period.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 66 92 67 94 68 / 10 10 5 5 5
San Angelo 67 93 68 95 68 / 10 10 5 5 5
Junction 68 94 69 97 66 / 10 10 5 5 5
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
336 PM CDT Fri Aug 16 2013
.SHORT TERM...
/Tonight and Tomorrow/
Visible satellite imagery shows sunny skies across West Central
Texas this afternoon. The latest mesoanalysis indicates a stable
environment over our area, with an instability axis across South and
far West Texas.
The models, including the 3KM HRRR model develop scattered
thunderstorms over Eastern New Mexico and far West Texas in the
instability axis during the late afternoon and evening. Upper level
northerly flow will keep this activity west of our area for tonight.
Lows will be in the mid 60s to lower 70s.
Going with a dry forecast for Saturday across the area. Isolated
thunderstorms will probably fire to our west during the afternoon
hours. The upper level northerly flow should keep the storms west of
our area. Highs will be in the lower to mid 90s.
.LONG TERM...
/Saturday Night through Friday/
The upper level flow will be north to northeast next week as a high
pressure ridge sets up from the Southern Rockies into the Central
Plains. Basically a normal summertime pattern with little upper
level and mesoscale forcing. Temperatures will be near or slightly
above seasonable normals. Highs will be in the 90s with lows in the
upper 60s to lower 70s. Going with a dry forecast through the
extended period.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 66 92 67 94 68 / 10 10 5 5 5
San Angelo 67 93 68 95 68 / 10 10 5 5 5
Junction 68 94 69 97 66 / 10 10 5 5 5
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION
NWS MIDLAND/ODESSA TX
154 PM CDT Fri Aug 16 2013
.DISCUSSION...
The Mesoscale Convective Complex which clipped the western Low
Rolling Plains this morning generated quite the bubble surface high
and sent an outflow boundary westward across the CWA. The modified
airmass behind this boundary will result in high temperatures
several degrees lower than what was previously expected, especially
over the eastern half of the forecast area, and will affect
convection this afternoon, and more than likely, tonight. The
latest RUC bears this out with a higher theta e axis at H7 shunted
west of the 16/12Z operational models. Think we will still see
widely scattered thunderstorms over the higher terrain through max
heating, but think convection will drop into southeast New Mexico
along the theta e axis overnight. Instability around 1000 J/Kg, mid
level lapse rates of 7.5-8 C/Km and 0-6 Km Bulk Shear Vectors around
35kt could yield a few strong to severe storms. Since the overall
threat is limited, will make a mention in the HWO.
Think convection Saturday and Sunday will mainly occur over the
higher terrain as an upper ridge over Arizona repositions further
north over the Four Corners region, with the flow aloft over the CWA
becoming more northeasterly. Storms will likely develop over the
higher terrain of New Mexico each afternoon, then spread south/
southwestward under the eastern fringe of the upper ridge.
Temperatures will stay near to above normal through the weekend.
Models are still undecided on whether an inverted upper trough will
trek westward into the area from the Gulf of Mexico next week. Will
not add any rain chances at this time, but some could be added mid
to late next week for such a feature if the upper ridge does not
remain too strong for it to impinge upon the area. Temperatures
should be near normal next week, especially the second half.
&&
.PRELIMINARY POINT TEMPS/POPS...
ANDREWS TX 69 94 70 95 / 10 10 10 0
BIG SPRING TX 72 95 70 96 / 10 10 10 0
CARLSBAD NM 70 98 71 99 / 30 10 20 10
DRYDEN TX 74 104 74 103 / 10 20 10 0
FORT STOCKTON TX 73 97 71 96 / 20 20 10 10
GUADALUPE PASS TX 66 94 68 92 / 20 20 20 20
HOBBS NM 67 94 67 93 / 30 10 20 0
MARFA TX 59 90 60 88 / 20 40 10 20
MIDLAND INTL AIRPORT TX 71 96 69 96 / 10 10 10 10
ODESSA TX 71 96 70 96 / 10 10 10 10
WINK TX 72 99 72 99 / 20 10 10 10
&&
.MAF WATCHES/WARNINGS/ADVISORIES...
NM...NONE.
TX...NONE.
&&
$$
10/67
AREA FORECAST DISCUSSION
NWS SPOKANE WA
236 PM PDT Fri Aug 16 2013
.SYNOPSIS...
A slow moving upper level trough will keep unsettled conditions
over the Inland Northwest through Saturday. The trough will pass
all areas by Saturday evening and Sunday delivering locally breezy
winds. Westerly flow will build over the region through the middle
of the week bringing dry weather and seasonable temperatures. The
weather will turn more unsettled toward the end of the next work
week with a return of some thunderstorms possible.
&&
.DISCUSSION...
Tonight: The Pacific Northwest will transition to a more
progressive flow pattern tonight into the weekend. An impressive
looking low pressure system over the Aleutians this afternoon will
direct a stronger upper level jet into the region over the next
couple of days. The increase in mid and upper level flow will aid
in the organization of thunderstorms over central Oregon this
afternoon and evening. We will be keeping a close eye on how
storms in Oregon evolve this evening, and their potential to
migrate into southeast Washington. At this time, RUC analysis of
instability suggests that storms will have a tough time surviving
once they move off the high terrain of central and northeast
Oregon. The last several runs of the NAM show thunderstorms
reaching as far east as Garfield and Asotin counties this evening.
Then overnight, the model regenerates elevated showers and
thunderstorms along the 700-500mb baroclinic axis from northeast
Oregon across the Camas Prairie to southern Shoshone county.
Precipitation amounts from any late night convection should be
pretty light. Model soundings suggest marginal elevated
instability and rapid cell motion.
Saturday and Saturday Night: On shore flow will strengthen
tomorrow as a shallow open-wave trough moves inland. The models are
in good agreement that there will be enough lingering low and mid
level moisture over northeast Oregon and the southern Idaho
Panhandle to retain a slight chance of showers and thunderstorms
over the Blues, Camas Prairie and Shoshone county. There may also
be enough cooling aloft with the upper trough axis to generate
isolated afternoon showers and thunderstorms over the mountains
near Northport, Priest Lake and Bonners Ferry.
Otherwise, Saturday afternoon/evening will be one of the breezier
days we have had in a while which isn`t saying much. Our recent
weather pattern hasn`t produced much widespread breeziness
lately. The Palouse, West Plains and Upper Columbia Basin will
likely experience sustained winds up to 15 mph with gusts to
around 20 mph in the afternoon. /GKoch
Sunday through Wednesday evening: A fairly benign weather pattern
through mid week. The Inland Northwest will be under a relatively
dry westerly flow pattern. The jet stream will remain well north
of the region into BC, which will place the Inland Northwest on
the more stable side of the jet. Shortwave disturbances will
generally bring some showers north of the region into BC through
the period and may give us a little bit of wind as they do so.
Temperatures will by near average with highs in the 80s for most
valley locations. /SVH
Thursday and Friday: A Low from Northern California is expected to
pass through the SE portion of Washington and the Central ID
Panhandle during this period. The models are not agreeing on the
timing of the Low passing. The GFS and GEM are putting the passing
on Friday morning while the ECMWF is nearly 24 hours behind. A few
more model runs will hopefully resolve this issue. The models are
carrying more moisture with this Low. With that in mind, the
chances of receiving a wetting rain and possible isolated
thunderstorm in the vicinity of the Low is increased for the Blue
Mountains and Camas Prairie area. Temperatures are expected to
remain around the normals for the month of August. /JDC
&&
.AVIATION...
18Z TAFS: A mainly dry frontal passage is expected today and
tonight over the Inland Northwest. Some sprinkles will accompany
the front this morning around Moses Lake. Isolated thunderstorms
will be possible over the Cascades between 21z-01z. Clusters of
stronger thunderstorms are expected over central and northeast
Oregon this afternoon/evening. These storms may migrate (as
they weaken) toward Lewiston this evening. Additional high based
showers will be possible in the 08z-13z time frame over far
southeast Washington into the southern Idaho Panhandle. No ceiling
or visibility obstructions are anticipated with evening or
overnight showers/t-storms. /GKoch
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 63 84 60 83 60 83 / 10 10 10 0 0 0
Coeur d`Alene 59 84 58 83 56 83 / 10 10 10 0 0 0
Pullman 55 84 52 83 50 86 / 10 10 10 0 0 0
Lewiston 66 92 64 93 62 94 / 20 10 10 0 0 0
Colville 57 88 54 87 53 89 / 10 20 10 0 0 0
Sandpoint 55 82 53 83 50 82 / 10 10 10 0 0 0
Kellogg 58 82 57 81 56 83 / 20 10 10 0 0 0
Moses Lake 61 89 60 88 60 88 / 0 0 0 0 0 0
Wenatchee 66 87 64 88 64 88 / 0 0 0 0 0 0
Omak 61 89 61 89 61 89 / 0 10 10 0 0 0
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND SATURDAY
ISSUED AT 241 PM CDT FRI AUG 16 2013
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOWS A SPRAWLING
HIGH PRESSURE SYSTEM STRETCHING FROM THE NORTHERN MISSISSIPPI VALLEY
TO NEW ENGLAND. AS ONE SHORTWAVE DIGS OVER THE SOUTHERN PLAINS
WHILE ANOTHER SHIFTS EAST OVER MANITOBA...MID-LEVEL RIDGING IS
GRADUALLY BUILDING EAST OVER THE NORTHERN PLAINS. THIS PATTERN WILL
CONTINUE TO LEAD TO QUIET WEATHER OVER THE NEXT SEVERAL
DAYS...MAKING CLOUDS AND TEMPS THE MAIN FORECAST CONCERN IN THE
SHORT TERM.
TONIGHT...HIGH PRESSURE WILL REMAIN OVER THE REGION BENEATH BUILDING
HEIGHTS IN THE MID AND UPPER LEVELS. WISCONSIN WILL BE POSITIONED
BETWEEN WEATHER SYSTEMS NORTH AND SOUTH OF THE REGION. WITH LOW
PWATS AND MOSTLY CLEAR CONDITIONS...WILL LIKELY SEE PATCHY GROUND
FOG FORM LATE TONIGHT ACROSS THE SANDY SOIL AREAS AND RIVER VALLEYS.
WENT BELOW MOS GUIDANCE FOR LOWS...WHICH SHOULD BE A FEW DEGREES
WARMER THAN LAST NIGHT.
SATURDAY...HIGH PRESSURE THROUGH THE COLUMN WILL PROVIDE ANOTHER
QUIET AND SUNNY DAY. START TO GET A LITTLE MORE RETURN FLOW ACROSS
THE REGION...WHICH SHOULD LEAD TO SLIGHTLY WARMER HIGH TEMPS AND
MORE HUMIDITY. HIGHS MAINLY IN THE LOW TO MID 80S...EXCEPT COOLER
NEAR THE LAKE.
.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
ISSUED AT 241 PM CDT FRI AUG 16 2013
MODELS ARE NOW IN GOOD AGREEMENT WITH OVERALL PATTERN.
THEY BRING UPPER RIDGING INTO THE NORTHERN PLAINS AND WESTERN
GREAT LAKES THROUGH MIDWEEK. A SHORT WAVE TROUGH MOVING ALONG THE
CANADIAN BORDER WILL SUPPRESS THE RIDGING A BIT SUNDAY NIGHT AND
MONDAY AND COULD PRODUCE SCATTERED THUNDERSTORMS IN THE FAR NORTH.
PROLONGED SOUTHERLY FLOW AND WARMER TEMPERATURES ALOFT WILL
COMBINE TO PRODUCE VERY WARM AND MORE HUMID CONDITIONS DURING THE
MIDDLE OF THE WEEK WITH THE WARMEST WEATHER SINCE MID JULY. THE
HEAT SHOULD SUBSIDE AS A COLD FRONT MOVES THROUGH THURSDAY AND
THURSDAY NIGHT. COOLER AND DRIER AIR EXPECTED FRIDAY THROUGH
SUNDAY.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1207 PM CDT FRI AUG 16 2013
VFR CONDITIONS WILL PROVIDE GOOD FLYING WEATHER OVER THE
TAF PERIOD. SCATTERED CUMULUS CLOUDS WITH CIGS IN THE 5-7 KFT RANGE
TO BUILD MIDDAY BEFORE DISSIPATING EARLY THIS EVENING. BETWEEN
08-12Z SATURDAY MORNING...PATCHY GROUND FOG WILL IMPACT AREA
AIRPORTS. FOG WILL BE THE MOST WIDESPREAD AND DENSE OVER
NORTH-CENTRAL WISCONSIN.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......MPC