Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 07/30/13
AREA FORECAST DISCUSSION
NWS TUCSON AZ
920 AM MST SUN JUL 28 2013
.SYNOPSIS...EXPECT LESS THUNDERSTORM ACTIVITY THROUGH TUESDAY AS
DEEPER MOISTURE MOVES EAST OF THE AREA. THE DAILY CYCLE OF SCATTERED
MAINLY AFTERNOON AND EVENING THUNDERSTORMS WILL THEN RETURN DURING
THE LATTER PART OF THIS WEEK. DAYTIME TEMPERATURES THROUGH WEDNESDAY
WILL BE ABOVE NORMAL FOLLOWED BY A COOLING TREND BY NEXT WEEKEND.
&&
.DISCUSSION...VISIBLE SATELLITE IMAGERY AND SURFACE OBSERVATIONS
INDICATED BROKEN CIRROFORM CLOUDS ACROSS SE AZ AT THIS TIME.
DEWPOINTS VALID 16Z WERE GENERALLY IN THE LOWER TO MID 60S F...AND
THESE TEMPS WERE NEARLY 2-5 DEGS F LOWER VERSUS 24 HOURS AGO. 28/12Z
KTWC SOUNDING DEPICTED A MUCH DRIER PROFILE VERSUS 24 HOURS AGO...
WITH TOTAL PRECIP WATER OF 1.22 INCHES. STILL A FAIRLY UNSTABLE
ENVIRONMENT WITH LIFTED INDEX OF MINUS 5 AND MODIFIED SURFACE BASED
CAPE OF 1000-1300 J/KG. 28/12Z UPPER AIR PLOTS INDICATED HIGH
PRESSURE CENTERED OVER SWRN CHIHUAHUA AND 582 DM LOW PRESSURE
CENTERED OFF THE SRN CALIFORNIA COAST VICINITY 33N/124W. LIGHT
WLY/SWLY FLOW PREVAILED OVER SE AZ.
28/12Z RUC HRRR DEPICTED PRECIP ECHOES TO BE CONFINED TO GREENLEE...
GRAHAM AND COCHISE COUNTIES EAST OF TUCSON FROM LATE THIS MORNING
INTO EARLY THIS EVENING. THE OFFICIAL FORECAST HAS SCATTERED SHOWERS
AND THUNDERSTORMS ACROSS EASTERN SECTIONS THIS AFTERNOON AND THIS
EVENING. FOR NOW WILL MAINTAIN ISOLATED SHOWERS/TSTMS FOR THE TUCSON
METRO AREA. DRY CONDITIONS WILL PREVAIL ACROSS WRN/CENTRAL PIMA
COUNTY. THE BULK OF PRECIP SHOULD END AROUND OR SHORTLY AFTER SUNSET.
HIGH TEMPS THIS AFTERNOON WILL GENERALLY BE ABOUT 2-5 DEGS F WARMER
VERSUS SATURDAY. PLEASE REFER TO THE PREVIOUS DISCUSSION SECTION
BELOW FOR ADDITIONAL DETAIL.
&&
.PREV DISCUSSION /235 AM MST SUN JUL 28 2013/...MONDAY...MUCH DRIER
AIR OVER THE AREA UNDER SW FLOW ALOFT. ANY THUNDERSTORM ACTIVITY
WILL BE EAST OF TUCSON AND MOSTLY NEAR THE MOUNTAINS. HIGHS WILL BE
SIMILAR OR A DEGREE WARMER THAN TODAY.
TUESDAY...WITH UPPER HIGH MOVING INTO NEW MEXICO...FLOW ALOFT
BECOMES A BIT MORE E-SE. STILL A LIMITED THUNDERSTORM DAY WITH BEST
CHANCE OF STORMS WILL BE EAST OF TUCSON OVER THE MOUNTAINS AND
ALONG THE INTERNATIONAL BORDER FROM NOGALES EAST. HIGHS WILL BE
SIMILAR TO MONDAY.
WEDNESDAY...MOISTURE STARTS TO INCREASE UNDER E-SE FLOW ALOFT WITH
UPPER HIGH OVER NEW MEXICO. GFS/EUROPEAN/CANADIAN MODELS STILL
SHOWING THAT THIS DAY WILL BE THE HOTTEST IN THIS FORECAST CYCLE.
BASED ON 850-700 MB THICKNESS NUMBERS...WILL UP HIGHS 1-2 DEGREES
AREAWIDE. BELIEVE MOS NUMBERS A BIT TOO COOL.
THURSDAY THROUGH SATURDAY...LOW GRADE MONSOON FORECAST AS SCATTERED
AFTERNOON AND EVENING THUNDERSTORMS RETURN TO THE AREA. HIGHS WILL
BE COOLER THANKS TO THE ADDED MOISTURE.
&&
.AVIATION...VALID THRU 29/18Z. FEW-SCT070 SCT-BKN300 WITH ISOLD-
SCTD TSRA THIS AFTERNOON INTO EARLY THIS EVENING...MAINLY FROM KTUS
EAST. WIND GUSTS UP TO 40 KTS NEAR TSRA...OTHERWISE SURFACE WIND
GENERALLY LESS THAN 10 KTS AND DIURNAL IN DIRECTION. AVIATION
DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...A DRYING TREND WILL BEGIN TO TAKE HOLD TODAY WITH
LOWER DEWPOINTS AND LESS OF A THREAT OF THUNDERSTORMS...THEN EVEN
MORE SO MONDAY AND TUESDAY. MOISTURE WILL BEGIN TO SLOWLY INCREASE
AGAIN WEDNESDAY ONWARD FOR AN INCREASE IN THUNDERSTORM ACTIVITY.
WINDS THROUGH THE PERIOD WILL BE DIURNAL IN NATURE AND OCCASIONALLY
A BIT BREEZY DURING THE MID AFTERNOON HOURS.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
DISCUSSION...FRANCIS
PREV DISCUSSION...JG
AVIATION/FIRE WEATHER...CERNIGLIA
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
925 PM MDT MON JUL 29 2013
.UPDATE...
ISSUED AT 925 PM MDT MON JUL 29 2013
ACTIVE EVENING WITH JET CORE OVERHEAD AND SPEED MAX OF 80 KT SEEN
IN 00Z KGJT SOUNDING. IN ADDITION SHORTWAVE UPSTREAM OVER NORTHERN
UTAH CONTINUES TO MOVE EAST SUPPORTING THE LATEST ROUND OF
THUNDERSTORMS...ONE ENTERING NW CO AND THE OTHER FOLLOWING ON THE
HEELS OF EARLIER STRONG CONVECTION THAT TRACKED FROM CANYONLANDS
ALMOST DUE EAST OVER THE UNCOMPAHGRE PLATEAU...MONTROSE AND
GUNNISON. HRRR MODEL ADVERTISED AND IS HANDLING THESE TWO
SEPARATE AREAS VERY WELL ALTHOUGH PERHAPS A COUPLE OF HOURS SLOW.
EXPECT THIS ROUND TO BE THE LAST ONE FOR THE NIGHT...CLEARING THE
DIVIDE BY 4 AM. AREA UNDER MODERATE DEEP LAYER SHEAR AND
RELATIVELY HIGHER MUCAPES WHICH IS HELPING TO KEEP STORMS A LITTLE
BETTER ORGANIZED AND LONGER-LIVED. HOWEVER...DUE TO THE GENERAL
DOWNWARD TREND IN INTENSITY WITH STABILIZATION OVERNIGHT...FLASH
FLOOD WATCH HAS BEEN ALLOWED TO EXPIRE. REMAINING STORMS WILL BE
WEAKER...ALTHOUGH STILL CAPABLE OF PRODUCING BRIEF AND LOCALLY
HEAVY RAIN.
&&
.SHORT TERM...(TONIGHT THROUGH TUESDAY NIGHT)
220 PM MDT MON JUL 29 2013
SHORT WAVE ENERGY OVER UTAH WILL STREAM EASTWARD AND WILL BE THE
PRIMARY TRIGGER FOR LOCALIZED HEAVY SHOWERS. THE PRIME AREA
APPEARS TO BE THE MIDDLE SECTION OF THE FORECAST AREA...WITH THE
ENVIRONMENT ACROSS THE FAR SOUTH AND NEAR THE WYOMING BORDER NOT
AS CONDUCIVE FOR RECEIVING HEAVY SHOWERS. SPEED MAXIMA ALOFT IS
ASSOCIATED WITH THE SHORT WAVE AND MAY ENHANCE STORM TOP
DIVERGENCE AND HELP GENERATE LOCALIZED STRONG CELLS WITH SMALL
HAIL. THE PRIMARY THREAT REMAINS HEAVY RAINERS FROM TRAINING
CELLS. WITH SOME AREAS HAVING RECEIVED SIGNIFICANT RAINFALL THE
PAST TWO DAYS...THE FLASH FLOOD THREAT IS ELEVATED FOR THE
REMAINDER OF THE DAY. GIVEN THAT THE MOISTURE STREAM TRAILS BACK
TO NE NEVADA...SHOWERS WITH EMBEDDED STORMS MAY LINGER ACROSS THE
NORTH UNTIL LATE.
TUESDAY AND TUESDAY NIGHT...HIGH PRESSURE RIDGE BUILDS BEHIND DEPARTING
SHORT WAVE FOR INCREASED SUBSIDENCE AND DRY ADVECTION ALOFT. THIS
WEAKENS THE MONSOONAL MOISTURE STREAM INTO THE FOUR CORNERS AREA.
ACROSS THE NORTH... MOISTURE STREAM IS WEAKENING BUT STILL EXIST
FOR SCATTERED SHOWERS AND STORMS OVER NW COLORADO. ACROSS THE SRN
HALF WHERE LESS MID LEVEL FLOW EXISTS...DIABATIC HEATING OVER THE
HIGH TERRAIN WILL BE THE PRIMARY CONVECTIVE TRIGGER. AFTERNOON
CONVECTION SHOULD DIMINISH QUICKLY NEAR SUNSET AND BECOME MOSTLY
CLEAR OVERNIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
220 PM MDT MON JUL 29 2013
DRY CONDITIONS WITH VERY LIGHT WESTERLY FLOW CONTINUE THROUGH
WEDNESDAY NIGHT UNDER HIGH PRESSURE BEFORE A SHIFT TO
SOUTH/SOUTHWESTERLY FLOW. BY THURSDAY AFTERNOON PWAT VALUES
INCREASE TO A CONVECTION- FAVORABLE 0.8 TO 1.0 INCH OVER MUCH OF
THE AREA...ESPECIALLY OVER SOUTHEAST UTAH. TWO UPPER LEVEL
DISTURBANCES LOOK TO MOVE THROUGH EARLY THURSDAY MORNING AND
THURSDAY AFTERNOON...WHICH SUPPORT SCATTERED CONVECTION AROUND THE
AREA ESPECIALLY ALONG THE COLORADO RIVER CORRIDOR. AREAS IN
NORTHERN COLORADO/UTAH MAY SEE SHOWER INITIATION BY THE UPPER LEVEL JET AS
WELL. THE FIRST BURST OF ENERGY WILL BE WEAK...BUT MAY ALLOW SOME
THURSDAY MORNING CONVECTION UP OVER ELEVATED AREAS OF CENTRAL
COLORADO. CONVECTIVE ACTIVITY WILL INCREASE WITH SOLAR HEATING AND
WHILE A FEW LIGHT SHOWERS MAY PERSIST THROUGH THE NIGHT...MOST
WILL DISSIPATE AFTER SUNSET THURSDAY EVENING ONCE THE SHEAR AXIS
MOVES THROUGH THE AREA.
12Z GFS SHOWS A THIRD WEAK SHORTWAVE THURSDAY NIGHT ALONG THE
SOUTHERN UT/CO BORDER...BUT THE ECMWF HAS NOT RESOLVED THIS
FEATURE YET. A COUPLE OF SMALL DISTURBANCES ARE SCATTERED AMONG THE WX
MODELS THROUGH SATURDAY BUT WITH THESE DIFFERING OPINIONS...NOT
INCLINED TO FORECAST ENHANCED POPS FOR ANY OF THE FEATURES PAST
THURSDAY NIGHT.
SATURDAY NIGHT THROUGH MONDAY...LOW CONFIDENCE WITH LONG RANGE FORECAST
AT THIS TIME. GFS HAS HIGH PRESSURE PROGGED TO SHIFT SOUTHEAST AS
LOW PRESSURE MOVES EAST ALONG THE CANADA/US BORDER OVER NORTHERN
MONTANA. THIS WOULD CUT OFF THE MONSOONAL MOISTURE PLUME AGAIN
LIKELY UNTIL MID NEXT WEEK SOMETIME. 12Z ECMWF DIFFERS IN SHIFTING
THE TRANSPORT WINDS TO WESTERLY ON SUNDAY EVENING AND CONTINUING
DAILY DIURNAL SHOWERS INTO NEXT WEEK ALONG THE RIDGE AXIS.
TEMPERATURES WILL REMAIN NEAR NORMAL THROUGH MIDWEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 537 PM MDT MON JUL 29 2013
MAIN FORECAST CONCERN IS THE IMPACTS OF THUNDERSTORMS ON AREA
AIRPORTS THROUGH TONIGHT. CLUSTER OF STRONG STORMS WILL REMAIN
JUST SOUTH OF KGJT THROUGH 01Z...BUT SHOULD MOVE OVER KMTJ BY 01Z.
ELSEWHERE SCATTERED CONVECTION WILL BE IN THE VICINTY OF OTHER TAF
SITES. HIGH RESOLUTION MODELS SEEM TO HAVE A GOOD HANDLE ON
CURRENT TRENDS AND THEY BRING AREA OF STORMS IN CENTRAL UT
EASTWARD THROUGH WEST CENTRAL CO 05Z-10Z. SO HAVE THAT AREA TIMED
THROUGH WITH VCTS FOR NOW. AFTER THAT WAVE OF STORMS THINGS SHOULD
DRY OUT WITH LITTLE THREAT OF TSTMS UNTIL POSSIBLY AFT 18Z A KASE
AND KEGE. SINCE CONFIDENCE NOT HIGH ENOUGH AT THIS TIME...LEFT
THOSE SITES FREE OF VCTS.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
UPDATE...BWM
SHORT TERM...PF
LONG TERM...JAM
AVIATION...BWM
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1150 AM MDT SUN JUL 28 2013
.UPDATE...
ISSUED AT 1147 AM MDT SUN JUL 28 2013
BULK OF STRATIFORM PRECIPITATION STRETCHES FROM RIO BLANCO EAST TO
MC COY. SHOWERS AND THUNDERSTORMS ARE BEGINNING TO POP UP BEHIND
THE MAIN SYSTEM AS SKIES CLEAR AND DAYTIME HEATING FUELS
ATMOSPHERIC INSTABILITY. WIDESPREAD CONVECTION IS EXPECTED TO PICK
UP RAPIDLY BY 4PM. STORMS WILL PRODUCE HEAVY RAIN...GUSTY
WINDS...AND OCCASIONAL LIGHTNING. WILL BE CONTINUING TO KEEP AN
EYE ON STORMS FOR FLOODING POTENTIAL.
ANOTHER PUSH OF ENERGY IS EXPECTED TO REACH SOUTHEASTERN UTAH EARLY
THIS AFTERNOON AND WESTERN COLORADO BY LATER THIS
EVENING...KEEPING THE LIKELIHOOD HIGH FOR PRECIPITATION
THROUGHOUT THE REMAINDER OF THE DAY.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 305 AM MDT SUN JUL 28 2013
TODAY: WEAK WAVE CONTINUES TO PUSH ACROSS THE CENTRAL PORTION OF
THE FORECAST AREA THIS MORNING RESULTING IN A BAND OF SHOWER
ACTIVITY WHICH HAS PRODUCED STEADY RAIN DURING THE OVERNIGHT
HOURS. HRRR SHOWS THIS ACTIVITY MOVING EAST OF THE FORECAST AREA
AROUND DAYBREAK. MODELS SHOWING ANOTHER WEAK WAVE WILL MOVE EAST
ACROSS THE CENTRAL SECTIONS OF THE FORECAST AREA BY LATE MORNING
FORCING ANOTHER BAND OF SHOWER ACTIVITY. THE ATMOSPHERE IS QUITE
MOIST WITH FORECASTED PW AROUND 1.3 INCHES TODAY. WEAK DYNAMIC FORCING
WILL BE PRESENT ESPECIALLY OVER NORTHERN HALF OF THE AREA TODAY AS
A WEAK JET BRUSHES NORTHERN PORTIONS OF THE AREA. THE MAIN
FORECAST QUESTION TODAY WILL BE THE POTENTIAL FOR FLOODING. IT IS
EXPECTED THAT OVERCAST SKIES WILL PREVAIL DURING THE DAY AND
REDUCE DAYTIME HEATING POTENTIAL. IN ADDITION...STORM MOTION WILL
BE RELATIVELY FAST AGAIN TODAY. FOR THESE REASONS...DID NOT HOIST
ANY FLOODING HIGHLIGHTS BUT DID MENTION HEAVY RAIN POTENTIAL IN
THE FORECAST. WITH EXPECTED CLOUD COVER...HIGH TEMPERATURES TODAY
WILL BE WELL BELOW NORMAL.
SUNDAY NIGHT THROUGH MONDAY...HIGH PRESSURE WILL REMAIN SETTLED
OVER THE BIG BEND REGION OF TEXAS...ABUNDANT MONSOONAL MOISTURE WILL
STREAM OVER THE FORECAST AREA FROM THE SOUTHWEST-WEST. MODELS
CONTINUE TRENDING SLOWER IN DRYING THINGS OUT AND NOW SUPPORT PW
VALUES OF 0.8-1.0 INCHES INTO MONDAY AFTERNOON. ATMOSPHERIC RIPPLES
AND THE RIGHT ENTRANCE REGION OF THE UPPER JET WILL CONTINUE TO
PROVIDE MODEST DYNAMIC LIFT WITH AT LEAST SOME SHOWER/THUNDERSTORM
ACTIVITY LIKELY DURING THE OVERNIGHT HOURS INTO MONDAY MORNING EVEN
WITH THE LOSS/LACK OF DAYTIME HEATING. STEERING FLOW WINDS WILL BE
DECENT AT AROUND 15 KT FROM THE SW-W WHICH WOULD REDUCE THE FLASH
FLOODING THREAT AS THUNDERSTORMS WILL BE MOVING ALONG...BUT WITH WET
SOILS IN PLACE ANY ADDITIONAL RAINFALL WILL REMAIN A CONCERN. MODELS
DUE HINT AT SLIGHTLY DRIER AIR OVER THE FOUR CORNERS REGION MONDAY
AFTERNOON WITH THE GREATEST THREAT FOR THUNDERSTORMS OVER THE
NORTHERN TWO-THIRDS OF THE CWA. DAYTIME TEMPERATURES WILL REBOUND
SOMEWHAT MONDAY COMPARED TO SUNDAY DUE TO INCREASED SUNSHINE BUT
REMAIN SLIGHTLY BELOW SEASONAL VALUES.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 305 AM MDT SUN JUL 28 2013
MONDAY NIGHT THROUGH TUESDAY NIGHT...PW VALUES BEGIN A GRADUAL
DECREASE MONDAY NIGHT FALLING TO AROUND 0.6 INCHES BY TUESDAY
AFTERNOON LEADING TO A DOWNTURN IN THUNDERSTORM ACTIVITY. THE ZONAL
FLOW WILL FEATURE MORE RIDGING TUESDAY PROVIDING SUBSIDENCE CAUSING
THUNDERSTORMS TO BE MAINLY TERRAIN DRIVEN AND ACROSS THE NORTH.
DAYTIME TEMPERATURES WILL WARM AN ADDITIONAL FEW DEGREES.
RIDGE AXIS OVER WESTERN COLORADO WILL KEEP MAINLY DRY CONDITIONS
OVER THE FORECAST AREA ON WEDNESDAY. RIDGE AXIS WILL SLOWLY SHIFT
EAST ON THURSDAY THROUGH FRIDAY AND FLATTEN AS A CLOSED LOW MOVES
ACROSS THE PACIFIC NORTHWEST REGION. AS A RESULT...MONSOONAL MOISTURE
WILL RETURN OVER THE FORECAST AREA WITH A CHANCE OF AFTERNOON AND
EVENING SHOWERS AND THUNDERSTORMS THURSDAY THROUGH SATURDAY BEFORE
A DOWNTURN ON SUNDAY. SEASONABLE HIGH TEMPERATURES ARE EXPECTED
THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1147 AM MDT SUN JUL 28 2013
SHOWER AND THUNDERSTORM ACTIVITY IS BEGINNING TO INCREASE AND
INTENSIFY. STORMS WILL CONTINUE INTO THE EARLY EVENING HOURS.
EXPECT AREAS OF MVFR CIGS AND VSBYS NEAR THE STRONGER
STORMS...WITH LOCAL IFR CONDITIONS POSSIBLE AT THE HIGHER
ELEVATION SITES. MOUNTAINS WILL BE OBSCURED AT TIMES...ESPECIALLY
NEAR HEAVIER RAIN SHOWERS. SHOWER ACTIVITY WILL DIMINISH LATER
THIS EVENING...BUT AREAS OF FOG MAY PERSIST FOR A FEW HOURS
OVERNIGHT IN RAIN-SOAKED VALLEYS.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
UPDATE...JAM
SHORT TERM...MPM/TB
LONG TERM...MPM/TB
AVIATION...JAM
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1019 AM MDT SUN JUL 28 2013
.UPDATE...
ISSUED AT 1006 AM MDT SUN JUL 28 2013
BULK OF STRATIFORM PRECIPITATION STRETCHES FROM MEEKER SOUTHEAST
TO GUNNISON. SHOWERS ARE BEGINNING TO POP UP BEHIND THE MAIN
SYSTEM AS SKIES CLEAR AND DAYTIME HEATING FUELS ATMOSPHERIC INSTABILITY.
WIDESPREAD CONVECTION IS EXPECTED TO PICK UP RAPIDLY BY NOON.
STORMS WILL PRODUCE HEAVY RAIN...GUSTY WINDS...AND OCCASIONAL
LIGHTNING. WILL BE CONTINUING TO KEEP AN EYE ON STORMS FOR
FLOODING POTENTIAL.
ANOTHER PUSH OF ENERGY IS EXPECTED TO REACH SOUTHEASTERN UTAH EARLY
THIS AFTERNOON AND WESTERN COLORADO BY LATER THIS
EVENING...KEEPING THE LIKELIHOOD HIGH FOR PRECIPITATION
THROUGHOUT THE REMAINDER OF THE DAY.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 305 AM MDT SUN JUL 28 2013
TODAY: WEAK WAVE CONTINUES TO PUSH ACROSS THE CENTRAL PORTION OF
THE FORECAST AREA THIS MORNING RESULTING IN A BAND OF SHOWER
ACTIVITY WHICH HAS PRODUCED STEADY RAIN DURING THE OVERNIGHT
HOURS. HRRR SHOWS THIS ACTIVITY MOVING EAST OF THE FORECAST AREA
AROUND DAYBREAK. MODELS SHOWING ANOTHER WEAK WAVE WILL MOVE EAST
ACROSS THE CENTRAL SECTIONS OF THE FORECAST AREA BY LATE MORNING
FORCING ANOTHER BAND OF SHOWER ACTIVITY. THE ATMOSPHERE IS QUITE
MOIST WITH FORECASTED PW AROUND 1.3 INCHES TODAY. WEAK DYNAMIC FORCING
WILL BE PRESENT ESPECIALLY OVER NORTHERN HALF OF THE AREA TODAY AS
A WEAK JET BRUSHES NORTHERN PORTIONS OF THE AREA. THE MAIN
FORECAST QUESTION TODAY WILL BE THE POTENTIAL FOR FLOODING. IT IS
EXPECTED THAT OVERCAST SKIES WILL PREVAIL DURING THE DAY AND
REDUCE DAYTIME HEATING POTENTIAL. IN ADDITION...STORM MOTION WILL
BE RELATIVELY FAST AGAIN TODAY. FOR THESE REASONS...DID NOT HOIST
ANY FLOODING HIGHLIGHTS BUT DID MENTION HEAVY RAIN POTENTIAL IN
THE FORECAST. WITH EXPECTED CLOUD COVER...HIGH TEMPERATURES TODAY
WILL BE WELL BELOW NORMAL.
SUNDAY NIGHT THROUGH MONDAY...HIGH PRESSURE WILL REMAIN SETTLED
OVER THE BIG BEND REGION OF TEXAS...ABUNDANT MONSOONAL MOISTURE WILL
STREAM OVER THE FORECAST AREA FROM THE SOUTHWEST-WEST. MODELS
CONTINUE TRENDING SLOWER IN DRYING THINGS OUT AND NOW SUPPORT PW
VALUES OF 0.8-1.0 INCHES INTO MONDAY AFTERNOON. ATMOSPHERIC RIPPLES
AND THE RIGHT ENTRANCE REGION OF THE UPPER JET WILL CONTINUE TO
PROVIDE MODEST DYNAMIC LIFT WITH AT LEAST SOME SHOWER/THUNDERSTORM
ACTIVITY LIKELY DURING THE OVERNIGHT HOURS INTO MONDAY MORNING EVEN
WITH THE LOSS/LACK OF DAYTIME HEATING. STEERING FLOW WINDS WILL BE
DECENT AT AROUND 15 KT FROM THE SW-W WHICH WOULD REDUCE THE FLASH
FLOODING THREAT AS THUNDERSTORMS WILL BE MOVING ALONG...BUT WITH WET
SOILS IN PLACE ANY ADDITIONAL RAINFALL WILL REMAIN A CONCERN. MODELS
DUE HINT AT SLIGHTLY DRIER AIR OVER THE FOUR CORNERS REGION MONDAY
AFTERNOON WITH THE GREATEST THREAT FOR THUNDERSTORMS OVER THE
NORTHERN TWO-THIRDS OF THE CWA. DAYTIME TEMPERATURES WILL REBOUND
SOMEWHAT MONDAY COMPARED TO SUNDAY DUE TO INCREASED SUNSHINE BUT
REMAIN SLIGHTLY BELOW SEASONAL VALUES.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 305 AM MDT SUN JUL 28 2013
MONDAY NIGHT THROUGH TUESDAY NIGHT...PW VALUES BEGIN A GRADUAL
DECREASE MONDAY NIGHT FALLING TO AROUND 0.6 INCHES BY TUESDAY
AFTERNOON LEADING TO A DOWNTURN IN THUNDERSTORM ACTIVITY. THE ZONAL
FLOW WILL FEATURE MORE RIDGING TUESDAY PROVIDING SUBSIDENCE CAUSING
THUNDERSTORMS TO BE MAINLY TERRAIN DRIVEN AND ACROSS THE NORTH.
DAYTIME TEMPERATURES WILL WARM AN ADDITIONAL FEW DEGREES.
RIDGE AXIS OVER WESTERN COLORADO WILL KEEP MAINLY DRY CONDITIONS
OVER THE FORECAST AREA ON WEDNESDAY. RIDGE AXIS WILL SLOWLY SHIFT
EAST ON THURSDAY THROUGH FRIDAY AND FLATTEN AS A CLOSED LOW MOVES
ACROSS THE PACIFIC NORTHWEST REGION. AS A RESULT...MONSOONAL MOISTURE
WILL RETURN OVER THE FORECAST AREA WITH A CHANCE OF AFTERNOON AND
EVENING SHOWERS AND THUNDERSTORMS THURSDAY THROUGH SATURDAY BEFORE
A DOWNTURN ON SUNDAY. SEASONABLE HIGH TEMPERATURES ARE EXPECTED
THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 305 AM MDT SUN JUL 28 2013
SHOWER AND THUNDERSTORM AND THUNDERSTORM ACTIVITY WILL CONTINUE
THROUGH 16Z WITH ACTIVITY AND INTENSITY INCREASING BY LATE MORNING
AND CONTINUING INTO THE EARLY EVENING HOURS. EXPECT AREAS OF MVFR
CIGS AND VSBYS NEAR THE STRONGER STORMS...WITH LOCAL IFR
CONDITIONS POSSIBLE AT THE HIGHER ELEVATION SITES AFTER 16Z.
MOUNTAINS WILL BE OBSCURED AT TIMES...ESPECIALLY NEAR HEAVIER RAIN
SHOWERS. SHOWER ACTIVITY WILL DIMINISH LATER THIS EVENING.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
UPDATE...JAM
SHORT TERM...MPM/TB
LONG TERM...MPM/TB
AVIATION...TGJT
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
306 AM MDT SUN JUL 28 2013
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 305 AM MDT SUN JUL 28 2013
TODAY: WEAK WAVE CONTINUES TO PUSH ACROSS THE CENTRAL PORTION OF
THE FORECAST AREA THIS MORNING RESULTING IN A BAND OF SHOWER
ACTIVITY WHICH HAS PRODUCED STEADY RAIN DURING THE OVERNIGHT
HOURS. HRRR SHOWS THIS ACTIVITY MOVING EAST OF THE FORECAST AREA
AROUND DAYBREAK. MODELS SHOWING ANOTHER WEAK WAVE WILL MOVE EAST
ACROSS THE CENTRAL SECTIONS OF THE FORECAST AREA BY LATE MORNING
FORCING ANOTHER BAND OF SHOWER ACTIVITY. THE ATMOSPHERE IS QUITE
MOIST WITH FORECASTED PW AROUND 1.3 INCHES TODAY. WEAK DYNAMIC FORCING
WILL BE PRESENT ESPECIALLY OVER NORTHERN HALF OF THE AREA TODAY AS
A WEAK JET BRUSHES NORTHERN PORTIONS OF THE AREA. THE MAIN
FORECAST QUESTION TODAY WILL BE THE POTENTIAL FOR FLOODING. IT IS
EXPECTED THAT OVERCAST SKIES WILL PREVAIL DURING THE DAY AND
REDUCE DAYTIME HEATING POTENTIAL. IN ADDITION...STORM MOTION WILL
BE RELATIVELY FAST AGAIN TODAY. FOR THESE REASONS...DID NOT HOIST
ANY FLOODING HIGHLIGHTS BUT DID MENTION HEAVY RAIN POTENTIAL IN
THE FORECAST. WITH EXPECTED CLOUD COVER...HIGH TEMPERATURES TODAY
WILL BE WELL BELOW NORMAL.
SUNDAY NIGHT THROUGH MONDAY...HIGH PRESSURE WILL REMAIN SETTLED
OVER THE BIG BEND REGION OF TEXAS...ABUNDANT MONSOONAL MOISTURE WILL
STREAM OVER THE FORECAST AREA FROM THE SOUTHWEST-WEST. MODELS
CONTINUE TRENDING SLOWER IN DRYING THINGS OUT AND NOW SUPPORT PW
VALUES OF 0.8-1.0 INCHES INTO MONDAY AFTERNOON. ATMOSPHERIC RIPPLES
AND THE RIGHT ENTRANCE REGION OF THE UPPER JET WILL CONTINUE TO
PROVIDE MODEST DYNAMIC LIFT WITH AT LEAST SOME SHOWER/THUNDERSTORM
ACTIVITY LIKELY DURING THE OVERNIGHT HOURS INTO MONDAY MORNING EVEN
WITH THE LOSS/LACK OF DAYTIME HEATING. STEERING FLOW WINDS WILL BE
DECENT AT AROUND 15 KT FROM THE SW-W WHICH WOULD REDUCE THE FLASH
FLOODING THREAT AS THUNDERSTORMS WILL BE MOVING ALONG...BUT WITH WET
SOILS IN PLACE ANY ADDITIONAL RAINFALL WILL REMAIN A CONCERN. MODELS
DUE HINT AT SLIGHTLY DRIER AIR OVER THE FOUR CORNERS REGION MONDAY
AFTERNOON WITH THE GREATEST THREAT FOR THUNDERSTORMS OVER THE
NORTHERN TWO-THIRDS OF THE CWA. DAYTIME TEMPERATURES WILL REBOUND
SOMEWHAT MONDAY COMPARED TO SUNDAY DUE TO INCREASED SUNSHINE BUT
REMAIN SLIGHTLY BELOW SEASONAL VALUES.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 305 AM MDT SUN JUL 28 2013
MONDAY NIGHT THROUGH TUESDAY NIGHT...PW VALUES BEGIN A GRADUAL
DECREASE MONDAY NIGHT FALLING TO AROUND 0.6 INCHES BY TUESDAY
AFTERNOON LEADING TO A DOWNTURN IN THUNDERSTORM ACTIVITY. THE ZONAL
FLOW WILL FEATURE MORE RIDGING TUESDAY PROVIDING SUBSIDENCE CAUSING
THUNDERSTORMS TO BE MAINLY TERRAIN DRIVEN AND ACROSS THE NORTH.
DAYTIME TEMPERATURES WILL WARM AN ADDITIONAL FEW DEGREES.
RIDGE AXIS OVER WESTERN COLORADO WILL KEEP MAINLY DRY CONDITIONS
OVER THE FORECAST AREA ON WEDNESDAY. RIDGE AXIS WILL SLOWLY SHIFT
EAST ON THURSDAY THROUGH FRIDAY AND FLATTEN AS A CLOSED LOW MOVES
ACROSS THE PACIFIC NORTHWEST REGION. AS A RESULT...MONSOONAL MOISTURE
WILL RETURN OVER THE FORECAST AREA WITH A CHANCE OF AFTERNOON AND
EVENING SHOWERS AND THUNDERSTORMS THURSDAY THROUGH SATURDAY BEFORE
A DOWNTURN ON SUNDAY. SEASONABLE HIGH TEMPERATURES ARE EXPECTED
THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 305 AM MDT SUN JUL 28 2013
SHOWER AND THUNDERSTORM AND THUNDERSTORM ACTIVITY WILL CONTINUE
THROUGH 16Z WITH ACTIVITY AND INTENSITY INCREASING BY LATE MORNING
AND CONTINUING INTO THE EARLY EVENING HOURS. EXPECT AREAS OF MVFR
CIGS AND VSBYS NEAR THE STRONGER STORMS...WITH LOCAL IFR
CONDITIONS POSSIBLE AT THE HIGHER ELEVATION SITES AFTER 16Z.
MOUNTAINS WILL BE OBSCURED AT TIMES...ESPECIALLY NEAR HEAVIER RAIN
SHOWERS. SHOWER ACTIVITY WILL DIMINISH LATER THIS EVENING.
&&
$$
SHORT TERM...MPM/TB
LONG TERM...MPM/TB
AVIATION...TGJT
AREA FORECAST DISCUSSION
NWS TAUNTON MA
159 PM EDT SUN JUL 28 2013
.SYNOPSIS...
ANOTHER FRONTAL SYSTEM IMPACTS THE REGION LATE TODAY INTO EARLY
MONDAY WITH SCATTERED SHOWERS AND THUNDERSTORMS. HIGH PRESSURE
FROM THE GREAT LAKES TO THE MID ATLANTIC STATES DELIVERS DRY
WEATHER TO THE AREA WITH COMFORTABLE TEMPERATURES AND HUMIDITY
FROM LATE MONDAY THROUGH WEDNESDAY. ANOTHER SYSTEM APPROACHES NEW
ENGLAND LATE NEXT WEEK POSSIBLY BRINGING SCATTERED SHOWERS AND
THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
2 PM UPDATE...
RADAR SHOWING A SMALL AREA OF SHOWERS LIFTING NWD FROM THE
BERKSHIRES...WHILE ANOTHER AREA OF SHOWERS MOVING N FROM THE OCEAN
S OF LONG ISLAND. INSTABILITY IS CLOSE TO NIL ACROSS SNE WITH
MLCAPES ONLY 250 J/KG. DEEPER MOISTURE REMAINS ACROSS E NY AND W
NEW ENG WITH MID LEVEL DRIER AIR ACROSS EASTERN HALF OF NEW ENG.
BEST CHANCE FOR A FEW SHOWERS AND AN ISOLD TSTM THIS AFTERNOON
REMAINS ACROSS W NEW ENG WITH A BRIEF SPRINKLE POSSIBLE SE NEW
ENG.
HEAVIER SHOWERS AND ISOLD TSTMS MOVING NWD FROM DELMARVA COAST
ASSOCD WITH MID LEVEL SHORTWAVE AND WILL HAVE TO MONITOR THIS
AREA FOR POSSIBLE SHOWERS/TSTMS THIS EVENING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
TONIGHT... HIGH CHANCE POP IN PLACE ACROSS FORECAST AREA DURING
THIS EVENING AND OVERNIGHT DUE TO THE CONTINUED APPROACH OF COLD
FRONT...AND SOUTHERN NEW ENGLAND BEING UNDER THE RIGHT ENTRANCE
REGION OF ANOMALOUSLY STRONG UPPER JET FOR THIS TIME OF THE YEAR.
THUNDERSTORMS SHOULD REMAIN A POSSIBILITY INTO THE OVERNIGHT
HOURS. ALSO FOR TONIGHT AN ITEM OF CONCERN IS THAT RAP AND NAM
INDICATE ANOTHER WEAK COASTAL LOW TRACKING NEAR THE CAPE AND
ISLANDS...APPEARS TO BE ASSOCIATED WITH CONVECTION OFF THE
CAROLINA COASTLINE AS OF 0830Z. OTHER MODELS ARE NOT LATCHING ONTO
THIS FEATURE BUT THIS MAY BE ANOTHER ITEM TO MONITOR FOR THE 12Z
MODEL RUN. AS MENTIONED...CHANCE POPS IN PLACE.
DEWPOINTS IN THE MID TO UPPER 60S WILL GIVE A MUGGY FEEL TO THE
AIR AND LIKELY CONDUCIVE TO AREAS OF FOG.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
HIGHLIGHTS...
* DRIER/LESS HUMID AND COOLER MON NGT THRU WED
* POSSIBLY UNSETTLED AT TIMES THU-SAT WITH RISK OF SHOWERS/TSTMS
SYNOPTIC OVERVIEW...
ACTIVE WEATHER PATTERN CONTINUES NEXT WEEK AS UPPER AIR FLOW
CONTINUES TO BE MARKED BY A ROBUST/ENERGETIC NORTHERN STREAM JET
ACROSS THE GREAT LAKES INTO THE NORTHEAST. THE PERIOD BEGINS WITH AN
ANOMALOUS UPPER LOW OVER THE NORTHERN GREAT LAKES/ONTARIO. AS THIS
FEATURE TRAVERSES NORTHEAST INTO QUEBEC IT SWEEPS A SIGNIFICANT COLD
FRONT ACROSS NEW ENGLAND MON WITH A MUCH DRIER/LESS HUMID POST
FRONTAL AIRMASS OVER THE AREA BEGINNING LATE MON AND CONTINUING INTO
WED. BY THU RENEWED SHORT WAVE ENERGY RELOADS/REINVIGORATES THE LONG
WAVE TROUGH OVER THE GREAT LAKES AND SOUTHEAST CANADA. THIS WILL
RESULT IN A SERIES OF JET IMPULSES AND ATTENDING FRONTS TO SWEEP
ACROSS THE AREA...INCREASING THE CHANCES FOR ANOTHER ROUND OF
SHOWERS/TSTMS LATE NEXT WEEK. BY NEXT WEEKEND ECENS AND GEFS
ENSEMBLES SUGGEST A TREND TOWARD COOLER WEATHER AS THE POLAR VORTEX
MOVES EQUATORWARD INTO NORTHEAST QUEBEC.
SENSIBLE WEATHER...
MONDAY...COLD FRONT MOVING ACROSS THE REGION AND ACCOMPANIED BY
STRONG JET DYNAMICS WITH AN IMPRESSIVE +3 STD JET STREAK OVER NEW
ENGLAND AND ITS RRQ CENTERED ACROSS THE AREA. THIS PROVIDES 0-6 KM
DEEP LAYER SHEAR OF 35-40 KT. MODEST INSTABILITY PROJECTED ALONG AND
AHEAD OF FRONT WITH ECMWF/GFS AND NAM INDICATING MUCAPES UP 1500J/KG
AT 18Z MON ACROSS RI AND EASTERN MA. HOWEVER LIMITING FACTOR HERE
FOR DEEP CONVECTION IS THAT CROSS SECTIONS REVEAL COLUMN DRIES OUT
SIGNIFICANTLY AND WILL INHIBIT CONVECTIVE CHANCES. THUS WILL LIMIT
POPS TO SLIGHT CHANCE FOR NOW BUT LATER SHIFTS SHOULD MONITOR FOR
ANY CHANGES.
LOOKING AT A WARM DAY GIVEN THE MILD START AND POST FRONTAL AIRMASS
NOT ARRIVING UNTIL LATE IN THE DAY. IT WILL BECOME LESS HUMID FROM
WEST TO EAST DURING THE AFTERNOON AND ESPECIALLY AT NIGHT.
TUESDAY/WEDNESDAY...SPECTACULAR WEATHER WITH MUCH DRIER/LESS HUMID
POST FRONTAL AIRMASS OVERSPREADING THE REGION YIELDING HIGHS
U70S/L80S AND DEW PTS IN THE 50S! SOME WARMING/AIRMASS MODIFICATION
WED WITH H85 TEMPS GOING FROM +10C TUE TO ABOUT +12C WED.
NONETHELESS ANOTHER PLEASANT DAY WED.
WEDNESDAY NIGHT THRU SAT...THE PATTERN THIS PERIOD WILL BE MARKED BY
A PARADE OF SHORT WAVES AND ATTENDING COLD FRONTS PROGRESSING
EASTWARD FROM THE GREAT LAKES/OH VLY INTO THE NORTHEAST. AT THIS
TIME RANGE ITS TOO DIFFICULT WITH ANY SKILL TO PIN-DOWN EXACT TIMING
OF SHOWERS/TSTMS. THUS WILL FORECAST SLIGHT CHANCE TO CHANCE POPS
HERE. NOT EXPECTING A COMPLETE WASHOUT AS THERE SHOULD BE MAIN
HOURS OF DRY WEATHER DURING THIS PORTION OF THE FORECAST.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
OVERALL...MODERATE CONFIDENCE BUT LOWER CONFIDENCE ON SPECIFIC
DETAILS INCLUDING TIMING.
THROUGH 00Z...IFR/MVFR CIGS ACROSS E COASTAL MA SHOULD LIFT TO
VFR.
TONIGHT...CIGS LOWERING TO MVFR/IFR...ESPECIALLY NEAR THE COAST
ALONG WITH PATCHY FOG. SCATTERED SHOWERS AND ISOLATED TSTMS
EXPECTED TO MOVE UP FROM THE S.
MONDAY AND MON NIGHT...PATCHY MVFR/IFR EARLY ALONG WITH A CHANCE
OF A SHOWER OR ISOLATED TSTM...THEN CONDITIONS IMPROVING TO VFR
AND PERSISTING THROUGH MON NIGHT.
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. MOSTLY MVFR CIGS
THROUGH TONIGHT ALTHOUGH A PERIOD OF VFR IS LIKELY THIS
AFTERNOON. LOW PROB FOR IFR CIGS TONIGHT.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF. WE HAVE MAINLY VFR
THROUGH THE PERIOD...BUT CANT RULE OUT A PERIOD OF MVFR CIGS
TONIGHT.
OUTLOOK...TUESDAY THROUGH THURSDAY...
TUE AND WED...VFR AND DRY WEATHER.
THU...VFR LIKELY WITH A LOW RISK OF SHRA.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
MODERATE TO HIGH CONFIDENCE.
THE LOW SHOULD PASS NORTHEAST OF THE WATERS BY MIDDAY...WITH
IMPROVING CONDITIONS FOR THE AFTERNOON.
THE AIR MASS WILL REMAIN VERY MOIST...WITH AREAS OF FOG TONIGHT.
AT THIS TIME...OTHER THAN LOCALIZED WIND GUSTS FROM TSTMS EARLY
THIS MORNING ON THE OUTER COASTAL WATERS...WINDS AND SEAS ARE
EXPECTED TO BE BELOW SCA CRITERIA FOR TODAY AND TONIGHT.
OUTLOOK...MONDAY THROUGH THURSDAY...
NO SIGNIFICANT WIND AND/OR WAVES-SWELLS EXPECTED THIS PERIOD.
MON...COLD FRONTAL PASSAGE WITH WIND SHIFT FROM SW TO W. ISOLATED
SHOWER/TSTM POSSIBLE.
TUE AND WED...FINE BOATING WEATHER WITH WEAK PRES OVER THE AREA. DRY
WEATHER AND GOOD VSBY.
THU...WEAK LOW PRES MAY APPROACH FROM THE WEST. CHANCE OF
SHOWERS/TSTMS.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...NOCERA/NMB
NEAR TERM...KJC
SHORT TERM...NMB
LONG TERM...NOCERA
AVIATION...KJC/NOCERA
MARINE...NOCERA/NMB
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1037 AM EDT SUN JUL 28 2013
.SYNOPSIS...
WEAK LOW PRESSURE WILL MOVE ACROSS CAPE COD AND THE ISLANDS THIS
MORNING. ANOTHER FRONTAL SYSTEM IMPACTS THE REGION LATE TODAY INTO
EARLY MONDAY WITH SCATTERED SHOWERS AND THUNDERSTORMS. HIGH
PRESSURE FROM THE GREAT LAKES TO THE MID ATLANTIC STATES DELIVERS
DRY WEATHER TO THE AREA WITH COMFORTABLE TEMPERATURES AND HUMIDITY
FROM LATE MONDAY THROUGH WEDNESDAY. ANOTHER SYSTEM APPROACHES NEW
ENGLAND LATE NEXT WEEK POSSIBLY BRINGING SCATTERED SHOWERS AND
THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1030 AM UPDATE...
SHOWERS/ISOLD TSTMS ASSOCD WITH WEAK LOW/CYCLONIC CIRCULATION
HAVE LIFTED N INTO THE GULF OF MAINE WHILE AREA OF SHOWERS ACROSS
THE BERKSHIRES ARE DECREASING IN COVERAGE. VISIBLE SATELLITE
INDICATING DEVELOPING SUNSHINE ACROSS CENTRAL MA AND NE CT AND
EXPECT THIS TO EXPAND EWD WITH CLOUDS GIVING WAY TO PTSUNNY SKIES
ACROSS THE COASTAL PLAIN WHERE AREA OF LOW AND MID LEVEL DRYING
DEVELOPS. FURTHER W ACROSS THE CT VALLEY AND BERKSHIRES...THERE
IS MORE MOISTURE IN THE COLUMN WHICH SUGGESTS MOCLDY SKIES HERE.
BEST CHANCE OF AFTERNOON CONVECTION WILL BE ACROSS W ZONES WHICH
IS CLOSEST TO DEEPER MOISTURE. FURTHER E...THERE APPEARS TO BE
ENOUGH MID LEVEL DRY AIR TO PRECLUDE CONVECTION. INSTABILITY IS
MARGINAL WITH CAPES FORECAST BELOW 1000 J/KG AND MID LEVEL LAPSE
RATES ARE UNFAVORABLE. BULK SHEAR IS FORECAST TO WEAKEN BELOW 30
KT ACROSS W NEW ENG THIS AFTERNOON. SEVERE WEATHER THREAT IS LOW.
WARMEST TEMPS THIS AFTERNOON SHOULD BE ACROSS NE CT...RI AND SE
MA WHERE DEVELOPING SUNSHINE WILL ALLOW TEMPS TO REACH INTO THE
LOW/MID 80S...AND RATHER HUMID SE NEW ENG WITH DEWPOINTS
REMAINING AROUND 70. COOLER 70S NE COASTAL MA AND HIGHER TERRAIN.
PREVIOUS DISCUSSION...
WEAK SURFACE LOW WITH THE TROPICAL MOISTURE SHOULD MOVE OFF INTO THE
GULF OF MAINE BY LATE MORNING. THE FOCUS THEN TURNS TOWARD AN
ANOMALOUSLY DEEP UPPER TROF AND COLD FRONT APPROACHING FROM THE
WEST. IMPRESSIVE JET DYNAMICS FOR JULY WEST OF OUR CWA...BUT THE
BEST DYNAMICAL LIFT IS EXPECTED TO LIFT NW AND N OF SOUTHERN NEW
ENGLAND. DURING THIS AFTERNOON THERE SHOULD BE LIMITED FORCING TO
TAP INTO INSTABILITY...SO HAVE KEPT POPS TO CHANCE ACROSS THE
AREA...HIGHEST POPS OVER CT RIVER VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
TONIGHT... HIGH CHANCE POP IN PLACE ACROSS FORECAST AREA DURING
THIS EVENING AND OVERNIGHT DUE TO THE CONTINUED APPROACH OF COLD
FRONT...AND SOUTHERN NEW ENGLAND BEING UNDER THE RIGHT ENTRANCE
REGION OF ANOMALOUSLY STRONG UPPER JET FOR THIS TIME OF THE YEAR.
THUNDERSTORMS SHOULD REMAIN A POSSIBILITY INTO THE OVERNIGHT
HOURS. ALSO FOR TONIGHT AN ITEM OF CONCERN IS THAT RAP AND NAM
INDICATE ANOTHER WEAK COASTAL LOW TRACKING NEAR THE CAPE AND
ISLANDS...APPEARS TO BE ASSOCIATED WITH CONVECTION OFF THE
CAROLINA COASTLINE AS OF 0830Z. OTHER MODELS ARE NOT LATCHING ONTO
THIS FEATURE BUT THIS MAY BE ANOTHER ITEM TO MONITOR FOR THE 12Z
MODEL RUN. AS MENTIONED...CHANCE POPS IN PLACE.
DEWPOINTS IN THE MID TO UPPER 60S WILL GIVE A MUGGY FEEL TO THE
AIR AND LIKELY CONDUCIVE TO AREAS OF FOG.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
HIGHLIGHTS...
* DRIER/LESS HUMID AND COOLER MON NGT THRU WED
* POSSIBLY UNSETTLED AT TIMES THU-SAT WITH RISK OF SHOWERS/TSTMS
SYNOPTIC OVERVIEW...
ACTIVE WEATHER PATTERN CONTINUES NEXT WEEK AS UPPER AIR FLOW
CONTINUES TO BE MARKED BY A ROBUST/ENERGETIC NORTHERN STREAM JET
ACROSS THE GREAT LAKES INTO THE NORTHEAST. THE PERIOD BEGINS WITH AN
ANOMALOUS UPPER LOW OVER THE NORTHERN GREAT LAKES/ONTARIO. AS THIS
FEATURE TRAVERSES NORTHEAST INTO QUEBEC IT SWEEPS A SIGNIFICANT COLD
FRONT ACROSS NEW ENGLAND MON WITH A MUCH DRIER/LESS HUMID POST
FRONTAL AIRMASS OVER THE AREA BEGINNING LATE MON AND CONTINUING INTO
WED. BY THU RENEWED SHORT WAVE ENERGY RELOADS/REINVIGORATES THE LONG
WAVE TROUGH OVER THE GREAT LAKES AND SOUTHEAST CANADA. THIS WILL
RESULT IN A SERIES OF JET IMPULSES AND ATTENDING FRONTS TO SWEEP
ACROSS THE AREA...INCREASING THE CHANCES FOR ANOTHER ROUND OF
SHOWERS/TSTMS LATE NEXT WEEK. BY NEXT WEEKEND ECENS AND GEFS
ENSEMBLES SUGGEST A TREND TOWARD COOLER WEATHER AS THE POLAR VORTEX
MOVES EQUATORWARD INTO NORTHEAST QUEBEC.
SENSIBLE WEATHER...
MONDAY...COLD FRONT MOVING ACROSS THE REGION AND ACCOMPANIED BY
STRONG JET DYNAMICS WITH AN IMPRESSIVE +3 STD JET STREAK OVER NEW
ENGLAND AND ITS RRQ CENTERED ACROSS THE AREA. THIS PROVIDES 0-6 KM
DEEP LAYER SHEAR OF 35-40 KT. MODEST INSTABILITY PROJECTED ALONG AND
AHEAD OF FRONT WITH ECMWF/GFS AND NAM INDICATING MUCAPES UP 1500J/KG
AT 18Z MON ACROSS RI AND EASTERN MA. HOWEVER LIMITING FACTOR HERE
FOR DEEP CONVECTION IS THAT CROSS SECTIONS REVEAL COLUMN DRIES OUT
SIGNIFICANTLY AND WILL INHIBIT CONVECTIVE CHANCES. THUS WILL LIMIT
POPS TO SLIGHT CHANCE FOR NOW BUT LATER SHIFTS SHOULD MONITOR FOR
ANY CHANGES.
LOOKING AT A WARM DAY GIVEN THE MILD START AND POST FRONTAL AIRMASS
NOT ARRIVING UNTIL LATE IN THE DAY. IT WILL BECOME LESS HUMID FROM
WEST TO EAST DURING THE AFTERNOON AND ESPECIALLY AT NIGHT.
TUESDAY/WEDNESDAY...SPECTACULAR WEATHER WITH MUCH DRIER/LESS HUMID
POST FRONTAL AIRMASS OVERSPREADING THE REGION YIELDING HIGHS
U70S/L80S AND DEW PTS IN THE 50S! SOME WARMING/AIRMASS MODIFICATION
WED WITH H85 TEMPS GOING FROM +10C TUE TO ABOUT +12C WED.
NONETHELESS ANOTHER PLEASANT DAY WED.
WEDNESDAY NIGHT THRU SAT...THE PATTERN THIS PERIOD WILL BE MARKED BY
A PARADE OF SHORT WAVES AND ATTENDING COLD FRONTS PROGRESSING
EASTWARD FROM THE GREAT LAKES/OH VLY INTO THE NORTHEAST. AT THIS
TIME RANGE ITS TOO DIFFICULT WITH ANY SKILL TO PIN-DOWN EXACT TIMING
OF SHOWERS/TSTMS. THUS WILL FORECAST SLIGHT CHANCE TO CHANCE POPS
HERE. NOT EXPECTING A COMPLETE WASHOUT AS THERE SHOULD BE MAIN
HOURS OF DRY WEATHER DURING THIS PORTION OF THE FORECAST.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
1030 AM UPDATE...
MODERATE TO HIGH CONFIDENCE ON OVERALL WEATHER THEME BUT LOWER
CONFIDENCE ON SPECIFIC DETAILS INCLUDING TIMING.
THIS MORNING...MVFR/IFR CIGS WITH AREAS OF FOG ACROSS TERMINALS
EARLY THIS MORNING. FOG AND STRATUS SHOULD GRADUALLY LIFT BY
MIDDAY.
THIS AFTERNOON...VFR PREVAILING AT TERMINALS EXCEPT CHANCE FOR
MVFR CIGS/VSBYS IN SCATTERED SHOWERS/TSTMS.
SUN NIGHT...EXPECTING AREAS OF LOW MVFR TO IFR CIGS/VSBYS
DEVELOPING IN AREAS OF FOG WITH SCATTERED SHOWERS/FEW TSTMS.
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. MVFR CIGS EXPECTED TO
BE PREVALENT EARLY THIS MORNING...THERE IS A LOW CHANCE OF IFR
CIGS.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF. IFR CIGS EXPECTED TO
LIFT AFTER DAYBREAK...THEN VFR. CHANCE FOR MVFR CIGS/VSBYS IN
SCATTERED TSTMS DURING THE AFTERNOON AND EVENING.
OUTLOOK...MONDAY THROUGH THURSDAY...
MONDAY...VFR LIKELY. LOW RISK OF AN ISOLATED SHRA/TSTM.
TUE AND WED...VFR AND DRY WEATHER.
THU...VFR LIKELY WITH A LOW RISK OF SHRA.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
MODERATE TO HIGH CONFIDENCE.
THE LOW SHOULD PASS NORTHEAST OF THE WATERS BY MIDDAY...WITH
IMPROVING CONDITIONS FOR THE AFTERNOON.
THE AIR MASS WILL REMAIN VERY MOIST...WITH AREAS OF FOG TONIGHT.
AT THIS TIME...OTHER THAN LOCALIZED WIND GUSTS FROM TSTMS EARLY
THIS MORNING ON THE OUTER COASTAL WATERS...WINDS AND SEAS ARE
EXPECTED TO BE BELOW SCA CRITERIA FOR TODAY AND TONIGHT.
OUTLOOK...MONDAY THROUGH THURSDAY...
NO SIGNIFICANT WIND AND/OR WAVES-SWELLS EXPECTED THIS PERIOD.
MON...COLD FRONTAL PASSAGE WITH WIND SHIFT FROM SW TO W. ISOLATED
SHOWER/TSTM POSSIBLE.
TUE AND WED...FINE BOATING WEATHER WITH WEAK PRES OVER THE AREA. DRY
WEATHER AND GOOD VSBY.
THU...WEAK LOW PRES MAY APPROACH FROM THE WEST. CHANCE OF
SHOWERS/TSTMS.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...NOCERA/NMB
NEAR TERM...KJC/NMB
SHORT TERM...NMB
LONG TERM...NOCERA
AVIATION...NOCERA/NMB
MARINE...KJC/NOCERA/NMB
AREA FORECAST DISCUSSION
NWS TAUNTON MA
658 AM EDT SUN JUL 28 2013
.SYNOPSIS...
WEAK LOW PRESSURE WILL MOVE ACROSS CAPE COD AND THE ISLANDS THIS
MORNING. ANOTHER FRONTAL SYSTEM IMPACTS THE REGION LATE TODAY INTO
EARLY MONDAY WITH SCATTERED SHOWERS AND THUNDERSTORMS. HIGH
PRESSURE FROM THE GREAT LAKES TO THE MID ATLANTIC STATES DELIVERS
DRY WEATHER TO THE AREA WITH COMFORTABLE TEMPERATURES AND HUMIDITY
FROM LATE MONDAY THROUGH WEDNESDAY. ANOTHER SYSTEM APPROACHES NEW
ENGLAND LATE NEXT WEEK POSSIBLY BRINGING SCATTERED SHOWERS AND
THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
7 AM UPDATE...
MESO ANALYSIS INDICATES WEAK LOW/CYCLONIC CIRCULATION OVER RI
SOUND. SHOWERS AND TSTMS ASSOCIATED WITH THIS FEATURE ARE CONFINED
TO THE OUTER CAPE AND NANTUCKET AND REMAIN PROGRESSIVE MOVING
NORTHEAST. AS LOW LIFTS NORTHEAST AND EXITS THE REGION SOME
SUNSHINE SHOULD DEVELOP YIELDING A WARM AND MUGGY AFTERNOON. UNTIL
THEN EXPECT SOME PATCHY DENSE FOG. UPSTREAM MOISTURE PLUME OVER
EASTERN PA AND NY STATE WILL BE SLOW TO MOVE EAST GIVEN IMPRESSIVE
MERIDIONAL FLOW ALONG THE EAST COAST. CURRENT FORECAST CAPTURES
THESE DETAILS NICELY SO LITTLE IF ANY CHANGES WITH THIS FORECAST
UPDATE. EARLIER DISCUSSION BELOW.
################################################################
445 AM UPDATE... SATELLITE IMAGERY AND RADAR INDICATING A LARGE
MCS BRUSHING OUR FAR EASTERN/SOUTHEASTERN ZONES...ASSOCIATED WITH
WEAK LOW PRESSURE CROSSING OVER THE CAPE AND ISLANDS EARLY THIS
MORNING. COLD TOPS AS LOW AS -70C OVERNIGHT WITH THE MCS BASED ON
IR IMAGERY. BASED ON TRAJECTORY OF RADAR RETURNS...LIGHTNING
RETURNS...AND LATEST RAP/NAM MODELS...HEAVIEST PRECIP SHOULD
REMAIN EAST OF THE CAPE AND ISLANDS...FALLING OVER THE COASTAL
WATERS AND BEYOND. UP TO AN INCH OF RAIN IS POSSIBLE OVER THE CAPE
AND ISLANDS EARLY THIS MORNING. OVER THE COASTAL WATERS...SOME OF
THIS CONVECTION IS ASSOCIATED WITH FREQUENT CLOUD TO GROUND
LIGHTNING...AT THIS TIME IT APPEARS HIGHEST CG FREQUENCY WILL PASS
E OF ACK.
THERE SHOULD BE A SHARP CUTOFF BETWEEN THE AREAS THAT GET
RAIN...AND THOSE THAT DO NOT FROM THIS LOW. HAVE TAPERED THE POPS SO
THAT WESTERN MA IS DRY THIS MORNING...CHANCE POP FOR MOST OF EAST
COASTAL MA AND RI...THEN CATEGORICAL FOR THE CAPE AND ISLANDS AND
SURROUNDING COASTAL WATERS TO START OFF THE DAY.
WEAK SURFACE LOW WITH THE TROPICAL MOISTURE SHOULD MOVE OFF INTO THE
GULF OF MAINE BY LATE MORNING. THE FOCUS THEN TURNS TOWARD AN
ANOMALOUSLY DEEP UPPER TROF AND COLD FRONT APPROACHING FROM THE
WEST. IMPRESSIVE JET DYNAMICS FOR JULY WEST OF OUR CWA...BUT THE
BEST DYNAMICAL LIFT IS EXPECTED TO LIFT NW AND N OF SOUTHERN NEW
ENGLAND. DURING THIS AFTERNOON THERE SHOULD BE LIMITED FORCING TO
TAP INTO INSTABILITY...SO HAVE KEPT POPS TO CHANCE ACROSS THE
AREA...HIGHEST POPS OVER CT RIVER VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
TONIGHT... HIGH CHANCE POP IN PLACE ACROSS FORECAST AREA DURING
THIS EVENING AND OVERNIGHT DUE TO THE CONTINUED APPROACH OF COLD
FRONT...AND SOUTHERN NEW ENGLAND BEING UNDER THE RIGHT ENTRANCE
REGION OF ANOMALOUSLY STRONG UPPER JET FOR THIS TIME OF THE YEAR.
THUNDERSTORMS SHOULD REMAIN A POSSIBILITY INTO THE OVERNIGHT
HOURS. ALSO FOR TONIGHT AN ITEM OF CONCERN IS THAT RAP AND NAM
INDICATE ANOTHER WEAK COASTAL LOW TRACKING NEAR THE CAPE AND
ISLANDS...APPEARS TO BE ASSOCIATED WITH CONVECTION OFF THE
CAROLINA COASTLINE AS OF 0830Z. OTHER MODELS ARE NOT LATCHING ONTO
THIS FEATURE BUT THIS MAY BE ANOTHER ITEM TO MONITOR FOR THE 12Z
MODEL RUN. AS MENTIONED...CHANCE POPS IN PLACE.
DEWPOINTS IN THE MID TO UPPER 60S WILL GIVE A MUGGY FEEL TO THE
AIR AND LIKELY CONDUCIVE TO AREAS OF FOG.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
HIGHLIGHTS...
* DRIER/LESS HUMID AND COOLER MON NGT THRU WED
* POSSIBLY UNSETTLED AT TIMES THU-SAT WITH RISK OF SHOWERS/TSTMS
SYNOPTIC OVERVIEW...
ACTIVE WEATHER PATTERN CONTINUES NEXT WEEK AS UPPER AIR FLOW
CONTINUES TO BE MARKED BY A ROBUST/ENERGETIC NORTHERN STREAM JET
ACROSS THE GREAT LAKES INTO THE NORTHEAST. THE PERIOD BEGINS WITH AN
ANOMALOUS UPPER LOW OVER THE NORTHERN GREAT LAKES/ONTARIO. AS THIS
FEATURE TRAVERSES NORTHEAST INTO QUEBEC IT SWEEPS A SIGNIFICANT COLD
FRONT ACROSS NEW ENGLAND MON WITH A MUCH DRIER/LESS HUMID POST
FRONTAL AIRMASS OVER THE AREA BEGINNING LATE MON AND CONTINUING INTO
WED. BY THU RENEWED SHORT WAVE ENERGY RELOADS/REINVIGORATES THE LONG
WAVE TROUGH OVER THE GREAT LAKES AND SOUTHEAST CANADA. THIS WILL
RESULT IN A SERIES OF JET IMPULSES AND ATTENDING FRONTS TO SWEEP
ACROSS THE AREA...INCREASING THE CHANCES FOR ANOTHER ROUND OF
SHOWERS/TSTMS LATE NEXT WEEK. BY NEXT WEEKEND ECENS AND GEFS
ENSEMBLES SUGGEST A TREND TOWARD COOLER WEATHER AS THE POLAR VORTEX
MOVES EQUATORWARD INTO NORTHEAST QUEBEC.
SENSIBLE WEATHER...
MONDAY...COLD FRONT MOVING ACROSS THE REGION AND ACCOMPANIED BY
STRONG JET DYNAMICS WITH AN IMPRESSIVE +3 STD JET STREAK OVER NEW
ENGLAND AND ITS RRQ CENTERED ACROSS THE AREA. THIS PROVIDES 0-6 KM
DEEP LAYER SHEAR OF 35-40 KT. MODEST INSTABILITY PROJECTED ALONG AND
AHEAD OF FRONT WITH ECMWF/GFS AND NAM INDICATING MUCAPES UP 1500J/KG
AT 18Z MON ACROSS RI AND EASTERN MA. HOWEVER LIMITING FACTOR HERE
FOR DEEP CONVECTION IS THAT CROSS SECTIONS REVEAL COLUMN DRIES OUT
SIGNIFICANTLY AND WILL INHIBIT CONVECTIVE CHANCES. THUS WILL LIMIT
POPS TO SLIGHT CHANCE FOR NOW BUT LATER SHIFTS SHOULD MONITOR FOR
ANY CHANGES.
LOOKING AT A WARM DAY GIVEN THE MILD START AND POST FRONTAL AIRMASS
NOT ARRIVING UNTIL LATE IN THE DAY. IT WILL BECOME LESS HUMID FROM
WEST TO EAST DURING THE AFTERNOON AND ESPECIALLY AT NIGHT.
TUESDAY/WEDNESDAY...SPECTACULAR WEATHER WITH MUCH DRIER/LESS HUMID
POST FRONTAL AIRMASS OVERSPREADING THE REGION YIELDING HIGHS
U70S/L80S AND DEW PTS IN THE 50S! SOME WARMING/AIRMASS MODIFICATION
WED WITH H85 TEMPS GOING FROM +10C TUE TO ABOUT +12C WED.
NONETHELESS ANOTHER PLEASANT DAY WED.
WEDNESDAY NIGHT THRU SAT...THE PATTERN THIS PERIOD WILL BE MARKED BY
A PARADE OF SHORT WAVES AND ATTENDING COLD FRONTS PROGRESSING
EASTWARD FROM THE GREAT LAKES/OH VLY INTO THE NORTHEAST. AT THIS
TIME RANGE ITS TOO DIFFICULT WITH ANY SKILL TO PIN-DOWN EXACT TIMING
OF SHOWERS/TSTMS. THUS WILL FORECAST SLIGHT CHANCE TO CHANCE POPS
HERE. NOT EXPECTING A COMPLETE WASHOUT AS THERE SHOULD BE MAIN
HOURS OF DRY WEATHER DURING THIS PORTION OF THE FORECAST.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
7 AM UPDATE...
MODERATE TO HIGH CONFIDENCE ON OVERALL WEATHER THEME BUT LOWER
CONFIDENCE ON SPECIFIC DETAILS INCLUDING TIMING.
THIS MORINING...MVFR/IFR CIGS WITH AREAS OF FOG ACROSS TERMINALS
EARLY THIS MORNING. FOG AND STRATUS SHOULD GRADUALLY LIFT BY MID
MORNING. ACROSS EAST COASTAL TERMINALS ESPECIALLY
CAPE/ISLANDS...SHOWERS AND SCT TSTMS CROSSING THE AREA
EARLY...SHOULD DEPART BY 14Z.
THIS AFTERNOON...VFR PREVAILING AT TERMINALS EXCEPT CHANCE FOR
MVFR CIGS/VSBYS IN SCATTERED SHOWERS/TSTMS.
SUN NIGHT...EXPECTING AREAS OF LOW MVFR TO IFR CIGS/VSBYS
DEVELOPING IN AREAS OF FOG WITH SCATTERED SHOWERS/FEW TSTMS.
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. MVFR CIGS EXPECTED TO
BE PREVALENT EARLY THIS MORNIING...THERE IS A LOW CHANCE OF IFR
CIGS. TSTM CLUSTER IS PRIMARILY EXPECTED TO AFFECT THE CAPE AND
COASTAL WATERS.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF. IFR CIGS EXPECTED TO
LIFT AFTER DAYBREAK...THEN VFR. CHANCE FOR MVFR CIGS/VSBYS IN
SCATTERED TSTMS DURING THE AFTERNOON AND EVENING.
OUTLOOK...MONDAY THROUGH THURSDAY...
MONDAY...VFR LIKELY. LOW RISK OF AN ISOLATED SHRA/TSTM.
TUE AND WED...VFR AND DRY WEATHER.
THU...VFR LIKELY WITH A LOW RISK OF SHRA.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
MODERATE TO HIGH CONFIDENCE.
WEAK LOW PRESSURE HAS PRODUCED A SIZEABLE CLUSTER OF THUNDERSTORMS
THAT WERE MOVING INTO THE COASTAL WATERS AS OF 445 AM. A PORTION
OF THIS THUNDERSTORM CLUSTER WILL CROSS THROUGH THE COASTAL WATERS
THROUGH 10 AM OR SO. FREQUENT CLOUD TO GROUND LIGHTNING HAS BEEN
ASSOCIATED WITH SOME OF THE STORMS...MAINLY OVER THE OUTER COASTAL
WATERS. PATCHY FOG IS EXPECTED.
THE LOW SHOULD PASS NORTHEAST OF THE WATERS BY MIDDAY...WITH
IMPROVING CONDITIONS FOR THE AFTERNOON.
THE AIR MASS WILL REMAIN VERY MOIST...WITH AREAS OF FOG TONIGHT.
AT THIS TIME...OTHER THAN LOCALIZED WIND GUSTS FROM TSTMS EARLY
THIS MORNING ON THE OUTER COASTAL WATERS...WINDS AND SEAS ARE
EXPECTED TO BE BELOW SCA CRITERIA FOR TODAY AND TONIGHT.
OUTLOOK...MONDAY THROUGH THURSDAY...
NO SIGNIFICANT WIND AND/OR WAVES-SWELLS EXPECTED THIS PERIOD.
MON...COLD FRONTAL PASSAGE WITH WIND SHIFT FROM SW TO W. ISOLATED
SHOWER/TSTM POSSIBLE.
TUE AND WED...FINE BOATING WEATHER WITH WEAK PRES OVER THE AREA. DRY
WEATHER AND GOOD VSBY.
THU...WEAK LOW PRES MAY APPROACH FROM THE WEST. CHANCE OF
SHOWERS/TSTMS.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...NOCERA/NMB
NEAR TERM...NOCERA/NMB
SHORT TERM...NMB
LONG TERM...NOCERA
AVIATION...NOCERA/NMB
MARINE...NOCERA/NMB
AREA FORECAST DISCUSSION
NWS TAUNTON MA
455 AM EDT SUN JUL 28 2013
.SYNOPSIS...
WEAK LOW PRESSURE WILL MOVE ACROSS CAPE COD AND THE ISLANDS THIS
MORNING. ANOTHER FRONTAL SYSTEM IMPACTS THE REGION LATE TODAY INTO
EARLY MONDAY WITH SCATTERED SHOWERS AND THUNDERSTORMS. HIGH
PRESSURE FROM THE GREAT LAKES TO THE MID ATLANTIC STATES DELIVERS
DRY WEATHER TO THE AREA WITH COMFORTABLE TEMPERATURES AND HUMIDITY
FROM LATE MONDAY THROUGH WEDNESDAY. ANOTHER SYSTEM APPROACHES NEW
ENGLAND LATE NEXT WEEK POSSIBLY BRINGING SCATTERED SHOWERS AND
THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
445 AM UPDATE... SATELLITE IMAGERY AND RADAR INDICATING A LARGE
MCS BRUSHING OUR FAR EASTERN/SOUTHEASTERN ZONES...ASSOCIATED WITH
WEAK LOW PRESSURE CROSSING OVER THE CAPE AND ISLANDS EARLY THIS
MORNING. COLD TOPS AS LOW AS -70C OVERNIGHT WITH THE MCS BASED ON
IR IMAGERY. BASED ON TRAJECTORY OF RADAR RETURNS...LIGHTNING
RETURNS...AND LATEST RAP/NAM MODELS...HEAVIEST PRECIP SHOULD
REMAIN EAST OF THE CAPE AND ISLANDS...FALLING OVER THE COASTAL
WATERS AND BEYOND. UP TO AN INCH OF RAIN IS POSSIBLE OVER THE CAPE
AND ISLANDS EARLY THIS MORNING. OVER THE COASTAL WATERS...SOME OF
THIS CONVECTION IS ASSOCIATED WITH FREQUENT CLOUD TO GROUND
LIGHTNING...AT THIS TIME IT APPEARS HIGHEST CG FREQUENCY WILL PASS
E OF ACK.
THERE SHOULD BE A SHARP CUTOFF BETWEEN THE AREAS THAT GET
RAIN...AND THOSE THAT DO NOT FROM THIS LOW. HAVE TAPERED THE POPS SO
THAT WESTERN MA IS DRY THIS MORNING...CHANCE POP FOR MOST OF EAST
COASTAL MA AND RI...THEN CATEGORICAL FOR THE CAPE AND ISLANDS AND
SURROUNDING COASTAL WATERS TO START OFF THE DAY.
WEAK SURFACE LOW WITH THE TROPICAL MOISTURE SHOULD MOVE OFF INTO THE
GULF OF MAINE BY LATE MORNING. THE FOCUS THEN TURNS TOWARD AN
ANOMALOUSLY DEEP UPPER TROF AND COLD FRONT APPROACHING FROM THE
WEST. IMPRESSIVE JET DYNAMICS FOR JULY WEST OF OUR CWA...BUT THE
BEST DYNAMICAL LIFT IS EXPECTED TO LIFT NW AND N OF SOUTHERN NEW
ENGLAND. DURING THIS AFTERNOON THERE SHOULD BE LIMITED FORCING TO
TAP INTO INSTABILITY...SO HAVE KEPT POPS TO CHANCE ACROSS THE
AREA...HIGHEST POPS OVER CT RIVER VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
TONIGHT... HIGH CHANCE POP IN PLACE ACROSS FORECAST AREA DURING
THIS EVENING AND OVERNIGHT DUE TO THE CONTINUED APPROACH OF COLD
FRONT...AND SOUTHERN NEW ENGLAND BEING UNDER THE RIGHT ENTRANCE
REGION OF ANOMALOUSLY STRONG UPPER JET FOR THIS TIME OF THE YEAR.
THUNDERSTORMS SHOULD REMAIN A POSSIBILITY INTO THE OVERNIGHT
HOURS. ALSO FOR TONIGHT AN ITEM OF CONCERN IS THAT RAP AND NAM
INDICATE ANOTHER WEAK COASTAL LOW TRACKING NEAR THE CAPE AND
ISLANDS...APPEARS TO BE ASSOCIATED WITH CONVECTION OFF THE
CAROLINA COASTLINE AS OF 0830Z. OTHER MODELS ARE NOT LATCHING ONTO
THIS FEATURE BUT THIS MAY BE ANOTHER ITEM TO MONITOR FOR THE 12Z
MODEL RUN. AS MENTIONED...CHANCE POPS IN PLACE.
DEWPOINTS IN THE MID TO UPPER 60S WILL GIVE A MUGGY FEEL TO THE
AIR AND LIKELY CONDUCIVE TO AREAS OF FOG.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
HIGHLIGHTS...
* DRIER/LESS HUMID AND COOLER MON NGT THRU WED
* POSSIBLY UNSETTLED AT TIMES THU-SAT WITH RISK OF SHOWERS/TSTMS
SYNOPTIC OVERVIEW...
ACTIVE WEATHER PATTERN CONTINUES NEXT WEEK AS UPPER AIR FLOW
CONTINUES TO BE MARKED BY A ROBUST/ENERGETIC NORTHERN STREAM JET
ACROSS THE GREAT LAKES INTO THE NORTHEAST. THE PERIOD BEGINS WITH AN
ANOMALOUS UPPER LOW OVER THE NORTHERN GREAT LAKES/ONTARIO. AS THIS
FEATURE TRAVERSES NORTHEAST INTO QUEBEC IT SWEEPS A SIGNIFICANT COLD
FRONT ACROSS NEW ENGLAND MON WITH A MUCH DRIER/LESS HUMID POST
FRONTAL AIRMASS OVER THE AREA BEGINNING LATE MON AND CONTINUING INTO
WED. BY THU RENEWED SHORT WAVE ENERGY RELOADS/REINVIGORATES THE LONG
WAVE TROUGH OVER THE GREAT LAKES AND SOUTHEAST CANADA. THIS WILL
RESULT IN A SERIES OF JET IMPULSES AND ATTENDING FRONTS TO SWEEP
ACROSS THE AREA...INCREASING THE CHANCES FOR ANOTHER ROUND OF
SHOWERS/TSTMS LATE NEXT WEEK. BY NEXT WEEKEND ECENS AND GEFS
ENSEMBLES SUGGEST A TREND TOWARD COOLER WEATHER AS THE POLAR VORTEX
MOVES EQUATORWARD INTO NORTHEAST QUEBEC.
SENSIBLE WEATHER...
MONDAY...COLD FRONT MOVING ACROSS THE REGION AND ACCOMPANIED BY
STRONG JET DYNAMICS WITH AN IMPRESSIVE +3 STD JET STREAK OVER NEW
ENGLAND AND ITS RRQ CENTERED ACROSS THE AREA. THIS PROVIDES 0-6 KM
DEEP LAYER SHEAR OF 35-40 KT. MODEST INSTABILITY PROJECTED ALONG AND
AHEAD OF FRONT WITH ECMWF/GFS AND NAM INDICATING MUCAPES UP 1500J/KG
AT 18Z MON ACROSS RI AND EASTERN MA. HOWEVER LIMITING FACTOR HERE
FOR DEEP CONVECTION IS THAT CROSS SECTIONS REVEAL COLUMN DRIES OUT
SIGNIFICANTLY AND WILL INHIBIT CONVECTIVE CHANCES. THUS WILL LIMIT
POPS TO SLIGHT CHANCE FOR NOW BUT LATER SHIFTS SHOULD MONITOR FOR
ANY CHANGES.
LOOKING AT A WARM DAY GIVEN THE MILD START AND POST FRONTAL AIRMASS
NOT ARRIVING UNTIL LATE IN THE DAY. IT WILL BECOME LESS HUMID FROM
WEST TO EAST DURING THE AFTERNOON AND ESPECIALLY AT NIGHT.
TUESDAY/WEDNESDAY...SPECTACULAR WEATHER WITH MUCH DRIER/LESS HUMID
POST FRONTAL AIRMASS OVERSPREADING THE REGION YIELDING HIGHS
U70S/L80S AND DEW PTS IN THE 50S! SOME WARMING/AIRMASS MODIFICATION
WED WITH H85 TEMPS GOING FROM +10C TUE TO ABOUT +12C WED.
NONETHELESS ANOTHER PLEASANT DAY WED.
WEDNESDAY NIGHT THRU SAT...THE PATTERN THIS PERIOD WILL BE MARKED BY
A PARADE OF SHORT WAVES AND ATTENDING COLD FRONTS PROGRESSING
EASTWARD FROM THE GREAT LAKES/OH VLY INTO THE NORTHEAST. AT THIS
TIME RANGE ITS TOO DIFFICULT WITH ANY SKILL TO PIN-DOWN EXACT TIMING
OF SHOWERS/TSTMS. THUS WILL FORECAST SLIGHT CHANCE TO CHANCE POPS
HERE. NOT EXPECTING A COMPLETE WASHOUT AS THERE SHOULD BE MAIN
HOURS OF DRY WEATHER DURING THIS PORTION OF THE FORECAST.
&&
.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
LOW TO MODERATE CONFIDENCE FOR THE REMAINDER OF TONIGHT INTO
SUNDAY NIGHT.
THIS MORINING...MVFR/IFR CIGS WITH AREAS OF FOG ACROSS TERMINALS
EARLY THIS MORNING. FOG AND STRATUS SHOULD GRADUALLY LIFT BY MID
MORNING. ACROSS EAST COASTAL TERMINALS ESPECIALLY
CAPE/ISLANDS...SHOWERS AND SCT TSTMS CROSSING THE AREA
EARLY...SHOULD DEPART BY 14Z.
THIS AFTERNOON...VFR PREVAILING AT TERMINALS EXCEPT CHANCE FOR
MVFR CIGS/VSBYS IN SCATTERED SHOWERS/TSTMS.
SUN NIGHT...EXPECTING AREAS OF LOW MVFR TO IFR CIGS/VSBYS
DEVELOPING IN AREAS OF FOG WITH SCATTERED SHOWERS/FEW TSTMS.
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. MVFR CIGS EXPECTED TO
BE PREVALENT EARLY THIS MORNIING...THERE IS A LOW CHANCE OF IFR
CIGS. TSTM CLUSTER IS PRIMARILY EXPECTED TO AFFECT THE CAPE AND
COASTAL WATERS BUT THERE IS A CHANCE THAT A TSTM MAY COME CLOSE TO
KBOS AREA BETWEEN 10 AND 14Z.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF. IFR CIGS EXPECTED TO
LIFT AFTER DAYBREAK...THEN VFR. CHANCE FOR MVFR CIGS/VSBYS IN
SCATTERED TSTMS DURING THE AFTERNOON AND EVENING.
OUTLOOK...MONDAY THROUGH THURSDAY...
MONDAY...VFR LIKELY. LOW RISK OF AN ISOLATED SHRA/TSTM.
TUE AND WED...VFR AND DRY WEATHER.
THU...VFR LIKELY WITH A LOW RISK OF SHRA.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
MODERATE TO HIGH CONFIDENCE.
WEAK LOW PRESSURE HAS PRODUCED A SIZEABLE CLUSTER OF THUNDERSTORMS
THAT WERE MOVING INTO THE COASTAL WATERS AS OF 445 AM. A PORTION
OF THIS THUNDERSTORM CLUSTER WILL CROSS THROUGH THE COASTAL WATERS
THROUGH 10 AM OR SO. FREQUENT CLOUD TO GROUND LIGHTNING HAS BEEN
ASSOCIATED WITH SOME OF THE STORMS...MAINLY OVER THE OUTER COASTAL
WATERS. PATCHY FOG IS EXPECTED.
THE LOW SHOULD PASS NORTHEAST OF THE WATERS BY MIDDAY...WITH
IMPROVING CONDITIONS FOR THE AFTERNOON.
THE AIR MASS WILL REMAIN VERY MOIST...WITH AREAS OF FOG TONIGHT.
AT THIS TIME...OTHER THAN LOCALIZED WIND GUSTS FROM TSTMS EARLY
THIS MORNING ON THE OUTER COASTAL WATERS...WINDS AND SEAS ARE
EXPECTED TO BE BELOW SCA CRITERIA FOR TODAY AND TONIGHT.
OUTLOOK...MONDAY THROUGH THURSDAY...
NO SIGNIFICANT WIND AND/OR WAVES-SWELLS EXPECTED THIS PERIOD.
MON...COLD FRONTAL PASSAGE WITH WIND SHIFT FROM SW TO W. ISOLATED
SHOWER/TSTM POSSIBLE.
TUE AND WED...FINE BOATING WEATHER WITH WEAK PRES OVER THE AREA. DRY
WEATHER AND GOOD VSBY.
THU...WEAK LOW PRES MAY APPROACH FROM THE WEST. CHANCE OF
SHOWERS/TSTMS.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...NOCERA
NEAR TERM...NMB
SHORT TERM...NMB
LONG TERM...NOCERA
AVIATION...NOCERA/NMB
MARINE...NOCERA/NMB
AREA FORECAST DISCUSSION
NWS MIAMI FL
920 AM EDT SUN JUL 28 2013
.UPDATE...
DO NOT HAVE ANY STRONG REASONING TO CHANGE THE CURRENT FORECAST.
THE 12Z MFL SOUNDING SHOWS PWAT REMAINING NEAR TWO INCHES WITH
VERY WEAK STEERING FLOW. THE LATEST HRRR IS INDICATING DEVELOPMENT
BEGINNING AROUND 15Z AND CONTINUING THROUGH THE AFTERNOON WITH
ERRATIC MOVEMENT. THIS SEEMS REASONABLE BASED ON THE SOUNDING. THE
PRIMARY THREAT STILL LOOKS TO BE LOCALLY HEAVY RAINFALL THE MOST
UNSTABLE LAYER BEING THE LOWEST ELEVATIONS WITH WEAK MID LEVEL
LAPSE RATES.
KOB
&&
.PREV DISCUSSION... /ISSUED 744 AM EDT SUN JUL 28 2013/
AVIATION...
ISOLATED LIGHT TO MODERATE SHRA CONTINUE TO PUSH NORTHEAST THIS
MORNING ACROSS THE ATLANTIC WATERS AND SHOULD NOT AFFECT THE EAST
COAST SITES. A MORE SOUTHEASTERLY FLOW IS EXPECTED THROUGH THE DAY
WHICH SHOULD KEEP SHRA/TSRA ACROSS MAINLY THE INTERIOR AND EAST
COASTAL AREAS.
PREV DISCUSSION... /ISSUED 349 AM EDT SUN JUL 28 2013/
DISCUSSION...
LATEST SURFACE ANALYSIS REVEALS RIDGE OF HIGH PRESSURE STRETCHING
FROM THE SW ATLANTIC ACROSS THE FLORIDA STRAITS AND INTO THE CENTRAL
GULF OF MEXICO WITH TROUGH OF LOW PRESSURE ACROSS THE AREA LAST
COUPLE OF DAYS NOW JUST TO OUR NORTH. SIMILAR FEATURES ARE ALSO
PRESENT AT THE UPPER LEVELS BUT THIS TIME THE AXIS OF THE RIDGE IS
RIGHT ACROSS THE AREA WITH UPPER LEVEL TROUGH DIGGING SOUTH WELL
INTO THE GULF AS IT APPROACHES THE EAST COAST. AT MID AND HIGH
LEVELS THE AREA HAS BEEN UNDER A DIFFLUENT FLOW PATTERN ASSOCIATED
WITH THESE FEATURES THAT HAVE RESULTED IN ABOVE NORMAL THUNDERSTORM
ACTIVITY PAST COUPLE OF DAYS. PRECIPITABLE WATER REMAINS ABOVE
NORMAL ACROSS THE AREA BY AS MUCH AS 20% PER BLENDED TPW SATELLITE
BASED PRODUCT.
FOR THE SHORT RANGE...THROUGH MONDAY NIGHT...MODELS AND ATMOSPHERIC
TRENDS IN PRETTY GOOD AGREEMENT. AREA WILL CONTINUE TO BE UNDER THE
INFLUENCE OF LINGERING LOW LEVEL TROUGH TO OUR NORTH AND UPPER LEVEL
TROUGH MOVING INTO THE SE TODAY WHICH IN COMBINATION WITH RIDGE
ACROSS THE GULF AND THE STRAITS WILL CONTINUE TO RESULT IN SOME
UPPER LEVEL DIVERGENCE TOO. MOISTURE LEVELS AROUND OR ABOVE NORMAL
WILL CONTINUE TO SUPPORT A GOOD CHANCE OF RAIN AGAIN TODAY WHEN
COMBINED WITH AFOREMENTIONED FEATURES AND SEA BREEZE/OUTFLOW
BOUNDARY INTERACTIONS. STORM MOTION VECTORS FROM AMONG WIDE RANGE
OF MODELS IS GENERALLY FROM THE WEST BUT LESS THAN 3 KNOTS. THIS IN
COMBINATION WITH LOW LEVEL FEATURES ABOVE WILL MEAN PATTERN WILL
FAVOR INTERIOR AND EAST COAST AS IT DID SATURDAY BUT GIVEN WEAK
STORM MOTION WE WILL STILL BE AT THE MERCY OF OUTFLOW, LAKE, AND SEA
BREEZE BOUNDARIES.
BY MONDAY LOW LEVEL RIDGE MOVES INTO THE AREA FARTHER PUSHING TROUGH
TO OUR NORTH. UPPER LEVEL TROUGH IS FORECAST TO BE WAY NORTH OF
THE AREA BY THEN. DESPITE THAT MOISTURE LEVELS WILL REMAIN AROUND OR
ABOVE NORMAL AS THERE IS PLENTY OF MOISTURE TO OUR EAST ACROSS THE
ATLANTIC. THIS TIME PATTERN WILL BE TRANSITIONING TO ONE FAVORING
ACTIVITY ACROSS INTERIOR AND WEST COAST IN AFTERNOON AND EVENING
WITH A CHANCE ALONG THE EAST COAST LATE MORNING/EARLY AFTERNOON.
STORM VECTORS WILL NOW BE SE BUT STILL LESS THAN 5 KNOTS SO OUTFLOW
BOUNDARIES, LAKE BREEZES, AND SEA BREEZES WILL STILL PLAY A LARGE
ROLE DETERMINING WHERE STORMS DEVELOP AND/OR GO.
GIVEN MOISTURE LEVELS...MAIN CONCERNS WITH STORMS TODAY AND TOMORROW
WILL BE LOCALLY HEAVY RAINFALL (DUE TO MOISTURE LEVELS AND SLOW
STORM MOTION), FREQUENT LIGHTNING, AND GUSTY WINDS IN THAT ORDER.
FOR THE EXTENDED RANGE...TUESDAY THROUGH SATURDAY...LOW LEVEL
EASTERLY FLOW WILL REMAIN IN PLACE WITH A MORE TYPICAL PATTERN OF
ISOLATED MORNING SHOWERS AND CHANCES OF THUNDERSTORMS LATE
MORNING/EARLY AFTERNOON FOR THE EAST COAST...AND THEN SCATTERED
AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS ALONG THE SEA BREEZE
BOUNDARIES ACROSS THE INTERIOR AND TOWARDS THE GULF COAST. THIS
PATTERN IS FORECAST TO PERSIST THROUGH THE MIDDLE TO LATTER PART OF
THE WEEK. THE SUBTROPICAL RIDGE IS FORECAST TO SHIFT SLIGHTLY TO THE
EAST TOWARDS THE END OF THE WEEK AS AN UPPER LEVEL TROUGH PUSHES
TOWARDS THE EAST COAST AND INTO THE WESTERN ATLANTIC. RAIN CHANCES
MAY THEN INCREASE AGAIN FOR THE EAST COAST BUT THE SCENARIO REMAINS
RATHER UNCERTAIN AT THIS TIME GIVEN DIVERGENCE AMONG GLOBAL MODELS.
AS FOR THE REMNANTS OF DORIAN...THE CONSENSUS AT THIS TIME CONTINUES
TO BE THAT THEY ARE LIKELY TO PASS TO OUR SOUTH AS A WAVE WEDNESDAY AND
THURSDAY WITH NO SIGNIFICANT LOCAL IMPACTS ANTICIPATED AT THIS TIME
BUT WILL CONTINUE TO MONITOR IN CASE THIS OUTLOOK CHANGES GOING
FORWARD.
MARINE...
LIGHT AND VARIABLE WINDS ACROSS THE GULF WATERS AND LAKE OKEECHOBEE TODAY
AND SOUTHERLY IN THE 10 TO 15 KNOTS RANGE ACROSS THE ATLANTIC WATERS
WILL TRANSITION TO A MORE EASTERLY WIND REGIME BY EARLY IN THE WEEK.
AS HIGH PRESSURE RIDGE BUILDS NORTH OF THE AREA TOWARD THE MIDDLE OF
THE WEEK INCREASING PRESSURE GRADIENT COULD RESULT IN WINDS IN THE 15
TO 20 KNOTS RANGE PARTICULARLY ACROSS THE SOUTHERN WATERS OFF MIAMI
DADE AND THE SOUTHERN AND OFF SHORE WATERS OF COLLIER AND MAINLAND
MONROE COUNTIES. WITH THIS SEAS ARE FORECAST TO INCREASE TO THE 2 TO
4 FEET RANGE AND OCCASIONALLY UP TO 5 FEET.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 89 76 89 78 / 50 20 30 20
FORT LAUDERDALE 88 79 89 79 / 50 20 30 20
MIAMI 89 78 90 79 / 50 20 30 20
NAPLES 89 75 92 76 / 30 20 30 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
335 PM EDT SUN JUL 28 2013
.SHORT TERM /TONIGHT THROUGH MONDAY/...
WEAK FRONTAL BOUNDARY DRAPED ACROSS THE CENTRAL CWFA THIS AFTERNOON.
LOW PRESSURE AND A WARM FRONT ARE SITUATED ACROSS THE FLORIDA
PANHANDLE. ISO/SCT CONVECTION HAS DEVELOPED AHEAD OF THE WAVE OF LOW
PRESSURE DOWN SOUTH. THIS ACTIVITY SHOULD AFFECT MAINLY AREAS ALONG
THE SOUTHERN CWFA BORDER. ISOLD SHRA HAVE DEVELOPED ACROSS NORTHEAST
GA IN THE HIGHER TERRAIN. WILL HAVE TO WATCH THE SHRA/TSRA IN THE SW
CORNER OF THE CWFA...MAY HAVE TO UP THE POPS TO LIKELY IF THE
ACTIVITY KEEPS SPREADING.
LATEST RUN OF THE HRRR DOESN`T DO MUCH WITH THE CONVECTION UP
NORTH...BUT KEEPS THE SOUTHERN ACTIVITY GOING UNTIL AROUND SUNSET.
THE POTENTIAL FOR SEVERE REMAINS LOW...BUT ANY THUNDERSTORM THAT
DEVELOPS WILL HAVE THE POTENTIAL TO PRODUCE LIGHTNING STRIKES AND
GUSTY WINDS.
HRRR DIMINISHES CONVECTION AFTER SUNSET AND KEEPS THE NIGHTTIME
MOSTLY DRY. SOME PATCHY FOG IS POSSIBLE...WITH THE SATURATED GROUND
AND COOLER OVERNIGHT LOWS.
WEAK...MOSTLY DIFFUSE...FRONTAL BOUNDARY REMAINS ACROSS THE SOUTHERN
CWFA TOMORROW. DRIER AIR DOES SETTLE ON THE NORTHERN SIDE OF THE
BOUNDARY. HOWEVER...SLIGHTLY HIGHER DEWPOINTS WILL REMAIN ACROSS THE
SOUTH. MOISTURE WILL CONTINUE TO POOL ALONG THE WEAK BOUNDARY...BUT
WITH WEAK FORCING AND MARGINAL INSTABILITY...CONVECTION IS EXPECTED
TO BE LIMITED AGAIN TOMORROW.
NLISTEMAA
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
ADDED SLIGHT CHANCE POPS IN PORTIONS OF THE NORTH TUESDAY DUE TO
OROGRAPHIC ENHANCEMENT WITH RELATIVELY LIGHT WINDS WITH ANY LOW
LEVEL MOISTURE. HAVE MADE OTHER MINOR ADJUSTMENTS TO TEMPS BASED
ON LATEST BLEND OF GUIDANCE...OTHERWISE FORECAST LOOKS TO BE ON
TRACK AND PREVIOUS DISCUSSION FOLLOWS...
BAKER
LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
/ISSUED 359 AM EDT SUN JUL 28 2013/
LARGE SCALE PATTERN NOT FCST TO CHANGE MUCH DURING THE LONG TERM
PERIOD. UNUSUALLY ACTIVE WESTERLIES ACROSS THE CONUS WITH LONG
WAVE TROUGHING OVER THE EAST WILL CONTINUE. AFTER A BRIEF DRY
PERIOD WITH RISING HEIGHTS IN THE MID LEVELS...APPEARS THAT
WESTERLIES WILL DROP BACK DOWN INTO THE SE BY WED MORNING
CONTINUING THRU AT LEAST THUR NIGHT. BACK TO THE RAIN WE GO. BEST
CHC APPEARS TO BE WED AFT THRU THURS AFT. HEIGHTS PROGGED TO RISE
AGAIN ON FRI BUT THE WESTERLIES WILL BE JUST TO OUR NORTH.
GFS/ECMWF SHOW A COLD FRONT JUST TO OUR NORTH IN TN. MOISTURE FROM
REMNANTS OF DORIAN ALSO PROGGED BY LATE FRI AND SAT TO PUSH NORTH
INTO THE EASTERN GULF AND NRN FL AND MUCH OF GA.
ALL THIS SAID...NOT SEEING ANY SIGN OF SIGNIFICANT HEAVY RAIN OR SVR
WX. PW VALUES HIGH BUT NOT ANYTHING UNUSUALLY HIGH FOR THIS TIME OF
YEAR WITH VALUES AROUND 1.5 IN TUE/WED INCREASING TO 1.5-2.0 IN
THUR/FRI/SAT. SFC DEWPOINTS GREATER THAN 70 AND MLCAPE GREATER THAN
800 J/KG FCST TO REMAIN CONFINED TO SE COUNTIES THRU THURS THEN
SPREADING AREA WIDE FRI. COULD SEE SIGNIFICANT INSTABILITY BY NEXT
WEEKEND BASED ON 00Z GFS.
SNELSON
&&
.AVIATION...
18Z UPDATE...
SCT-BKN VFR CIGS LIKELY THROUGH THE AFTERNOON. WILL LEAVE OUT
MENTION OF CONVECTION...AS PROBABILITIES ARE TOO LOW. MODELS ARE
NOT PRODUCING LOW CIGS TONIGHT...BUT SOME PATCHY GROUND FOG IS
POSSIBLE. VSBYS 4-6SM LIKELY. EVEN LESS CONVECTION TOMORROW...WITH
SCT VFR CLOUDS.
//ATL CONFIDENCE...18Z UPDATE...
HIGH CONFIDENCE ALL ELEMENTS.
NLISTEMAA
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 69 89 68 90 / 20 10 10 20
ATLANTA 69 87 68 88 / 20 10 10 20
BLAIRSVILLE 59 82 61 84 / 10 10 5 20
CARTERSVILLE 64 87 61 89 / 10 10 5 10
COLUMBUS 72 92 72 92 / 20 20 10 20
GAINESVILLE 66 87 68 86 / 20 10 5 20
MACON 71 91 69 91 / 30 20 20 20
ROME 63 87 61 89 / 10 10 5 10
PEACHTREE CITY 67 88 62 89 / 20 10 10 20
VIDALIA 73 91 73 90 / 30 30 20 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...NLISTEMAA
LONG TERM....SNELSON/BAKER
AVIATION...NLISTEMAA
AREA FORECAST DISCUSSION
NWS POCATELLO ID
853 PM MDT MON JUL 29 2013
.UPDATE...THUNDERSTORMS THAT PRODUCED GUSTY OUTFLOWS THROUGH
PORTIONS OF EASTERN IDAHO EARLIER THIS EVENING HAVE EITHER
DISSIPATED OR MOVED EAST INTO WYOMING PER RADAR/SAT IMAGERY.
ANOTHER WEAK AREA OF CONVECTION REMAINS ALONG THE UTAH BORDER WITH
ANOTHER AREA TRAILING BEHIND IT IN NORTHEAST NEVADA. MODELS STILL
HAVING A HARD TIME WITH PAINTING CONVECTION ACROSS THE REGION
OVERNIGHT. NAM PAINTS CONVECTION CONTINUING IN THE SOUTHERN
HIGHLANDS WHILE GFS AND HRRR PAINT AREA OF WEAK CONVECTION OVER
THE CENTRAL MOUNTAINS. BASED ON ONGOING CONVECTION...LEFT SLIGHTLY
HIGHER POPS OVER THE SOUTHERN HIGHLANDS BUT TWEAKED CENTRAL
MOUNTAINS UP SLIGHTLY TO JUST BELOW MENTIONABLE THRESHOLDS.
ONLY OTHER CHANGE THIS EVENING IS TO ADJUST RED FLAG HEADLINE. WE
WILL LET 427 AND 413 EXPIRE WITH CONVECTION REMAINING ISOLATED
TONIGHT AND TUESDAY. THE HEADLINE FOR 475 AND 476 WILL BE EXTENDED
INTO TUESDAY EVENING WITH AN EXPECTED REPEAT OF LOW HUMIDITIES AND
GUSTY WINDS. NO OTHER UPDATES ANTICIPATED THIS EVENING. DMH
&&
.PREV DISCUSSION... /ISSUED 206 PM MDT MON JUL 29 2013/
DISCUSSION...TODAY THROUGH MONDAY. CURRENT SATELLITE IMAGERY
SHOWS CUMULUS CLOUD DEVELOPMENT OVER THE LOST RIVER/PAHSIMEROI
MOUNTAINS AND THE SOUTHEAST HIGHLANDS. CURRENT RADAR IMAGERY SHOWS
SHOWERS AND THUNDERSTORMS OVER THE SOUTHEAST HIGHLANDS. MODELS
SHOW SCATTERED SHOWERS AND THUNDERSTORMS OVER THE SOUTHEAST
HIGHLANDS THIS AFTERNOON INTO EARLY EVENING WITH RESIDUAL MOISTURE
AND INSTABILITY. LOOK FOR ISOLATED THUNDERSTORMS OVER THE LOST
RIVER/PAHSIMEROI MOUNTAINS AND UPPER SNAKE HIGHLANDS THIS AFTERNOON
INTO EARLY EVENING. EXPECT WARMER AND DRIER CONDITIONS TUESDAY AND
WEDNESDAY AS HIGH PRESSURE BUILDS INTO THE AREA.
LOOK FOR ISOLATED THUNDERSTORMS AND ELEVATED WINDS ACROSS THE
CENTRAL MOUNTAINS LATE WEDNESDAY AS THE NEXT SYSTEM STARTS TO PUSH
THE UPPER LEVEL RIDGE EAST. THURSDAY LOOK FOR MODERATE TO STRONG
WINDS AND THUNDERSTORM DEVELOPMENT AT OR NEAR RED FLAG CRITERIA
ACROSS THE CENTRAL MOUNTAINS AS AN UPPER LEVEL LOW MOVES OVER
NORTHERN IDAHO THURSDAY INTO FRIDAY. RED FLAGS MAY BE NEEDED FOR
THE REST OF THE AREA FOR MODERATE TO HIGH WINDS AND LOW RELATIVE
HUMIDITY AS WELL ON THURSDAY. LOOK FOR COOLER TEMPERATURES
THURSDAY AND FRIDAY BEFORE WARMING UP THROUGH THE WEEKEND INTO
MONDAY WITH HIGH PRESSURE RIDGING BUILDING BACK IN. WYATT
AVIATION...EXPECT VFR CONDITIONS THE NEXT COUPLE OF DAYS. LOOK
FOR BREEZY WINDS THIS AFTERNOON FOR ALL TAF SITES.
ADDITIONALLY...LOOK FOR VICINITY THUNDERSTORMS FOR KIDA...KPIH AND
KBYI THIS AFTERNOON INTO EARLY EVENING WITH THUNDERSTORMS TO
THESE TAF SITES SOUTH. WYATT
FIRE WEATHER...RED FLAG WARNING STILL IN EFFECT UNTIL 9 PM FOR
ZONES 475 AND 476 FOR WIND GUSTS AND LOW HUMIDITY AND SOME SITES
HAVE VERIFIED ALREADY AT 2 PM. SCATTERED THUNDERSTORMS STILL
EXPECTED THIS EVENING IN 427 AND 413 AND RED FLAG WARNING FOR THOSE
STILL IN EFFECT ALSO UNTIL 9 PM. FRONTAL BOUNDARY BISECTS
SOUTHEAST IDAHO AND MORE MOIST CONDITIONS IN SOUTHEAST PART OF
DISTRICT ENHANCING THUNDERSTORM DEVELOPMENT WHILE TO THE NORTH OF
FRONT LOW HUMIDITY AND STRONGER WINDS PRESENT. EXPECT LESS
THUNDERSTORM COVERAGE TUESDAY WITH MAINLY ISOLATED COVERAGE IN THE
SOUTHEAST.
GK
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING IDZ413-427.
RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING IDZ475-476.
&&
$$
AREA FORECAST DISCUSSION
NWS BOISE ID
853 AM MDT SUN JUL 28 2013
.DISCUSSION...12Z BOI RAOB WAS 2-3C COOLER THAN YESTERDAY AT ALL
LEVELS SO TODAY WILL FINALLY BRING TEMPS DOWN TO NORMAL. AT 8 AM
MDT KCBX RADAR STILL SHOWED SHOWERS AND ISOLATED THUNDERSTORMS IN
SRN MALHEUR COUNTY AND MOST OF OWYHEE COUNTY... MOVING DUE EAST.
MOST OF THE PCPN WAS ALOFT PER THE LOW-LEVEL DRYNESS INDICATED IN
THE BOI RAOB. NAM AND HRRR MODELS END SHOWERS/STORMS IN MALHEUR
COUNTY AROUND NOON BUT KEEP THEM GOING ALONG THE ID/NV BORDER THIS
AFTERNOON...AND ONLY IN SRN TWIN FALLS COUNTY TONIGHT. THIS
ACTIVITY IS NOT FROM MONSOON MOISTURE BUT RATHER FROM THE UPPER
TROUGH COMING IN FROM THE NORTHWEST. DRIER AIR WILL COME IN FROM
THE WEST TONIGHT...AND MONDAY WILL BE SUNNY WITH NORMAL TEMPS. NO
UPDATES.
&&
.AVIATION...VFR. BROKEN MID-LEVEL CLOUDS AND ISOLATED SHOWERS SOUTH
OF THE SNAKE BASIN SHIFTING DUE EAST. ISOLATED THUNDERSTORMS ALONG
THE NEVADA BORDER. SCATTERED MID-LEVEL CLOUDS IN THE REST OF
SOUTHWESTERN IDAHO AND SOUTHEASTERN OREGON THROUGH TONIGHT. SURFACE
WINDS WILL BE LIGHT WEST OR NORTHWEST AROUND 10 KTS IN THE AFTERNOON
...BECOMING LIGHT AND VARIABLE AROUND SUNSET. WINDS ALOFT AT 10K
FEET MSL WILL BE WESTERLY AT 20 KTS.
&&
.PREV DISCUSSION...
SHORT TERM...TODAY THROUGH MONDAY...THUNDERSTORMS ACROSS SOUTH
HARNEY COUNTY THROUGH 2 AM PDT FIZZLED OVER SOUTH MALHEUR COUNTY
BY 3 AM PDT. MOISTURE WILL CONTINUE NEAR THE NV BORDER THIS MORNING.
AN UPPER IMPULSE OVER SW OREGON AT 315 AM PDT WILL EXIT SOUTHERN
TWIN FALLS COUNTY AROUND 3 PM MDT BUT WILL CROSS ELEVATED TERRAIN
EARLY TODAY SO HAVE INCLUDED ISOLATED THUNDERSTORMS NEAR THE NV
BORDER THIS MORNING AS WELL. STORMS FORMED FURTHER WEST THAN
EXPECTED AND MAY OVERACHIEVE OFF THE SIERRA NEVADA AGAIN TODAY.
PASSING UPPER LEVEL TROUGH /QUITE WIMPY COMPARED TO THE ONE COMING
MID WEEK/ IS STILL ON TRACK TO BRING NOT QUITE AS HOT TEMPERATURES
...TRENDING BACK TO NEAR NORMAL. TODAY/S TROUGH IS ALSO QUITE DRY
FOR THIS TIME OF YEAR PER PW PERCENTILES...SO STRONG RADIATIONAL
COOLING STILL SUPPORTS SHAVING A COUPLE DEGREES OFF MOS LOWS
TONIGHT. MIXING WILL BRING AFTERNOON WIND GUSTS TO AROUND 20-25 MPH
AGAIN THE NEXT COUPLE DAYS. DRY AND MOSTLY SUNNY EXCEPT NEAR THE NV
BORDER IN THE SHORT TERM.
LONG TERM...MONDAY NIGHT THROUGH SUNDAY...RIDGING BUILDS BACK OVER
THE AREA TUESDAY THOUGH WEDNESDAY BETWEEN SHORT WAVE TROUGHS.
TEMPERATURES WARM BACK UP AND WILL PEAK NEAR CLIMATOLOGICAL NORMALS
TUESDAY AND WEDNESDAY AFTERNOONS. AN UPPER LEVEL SHORT WAVE TROUGH
WILL APPROACH THE AREA LATE WEDNESDAY AFTERNOON BRINGING A CHANCE OF
THUNDERSTORMS. THE TROUGH WILL MOVE DIRECTLY OVER THE AREA ON
THURSDAY AND FRIDAY AND AN ASSOCIATED COLD FRONT WILL BRING COOLER
WEATHER TO THE REGION. TEMPERATURES SHOULD BE 6 TO 8 DEGREES BELOW
NORMAL ON THURSDAY AND FRIDAY. IT IS INTERESTING TO NOTE THAT THE
LAST WEEK OF JULY IS THE CLIMATOLOGICAL HOTTEST TIME OF THE YEAR IN
SOUTHWESTERN IDAHO AND SOUTHEASTERN OREGON...SO THE COOLDOWN LATER
IN THE WEEK WILL TAKE SOME OF THE BITE AWAY FROM THE DOG DAYS OF
SUMMER THIS YEAR. THE COOLDOWN LOOKS BRIEF WITH A WARMING TREND
BEGINNING NEXT WEEKEND AS RIDGING BUILDS BACK OVER THE AREA.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.
&&
$$
WEATHER.GOV/BOISE
DISCUSSION...LC
AVIATION.....LC
PRE VSHORT TERM...VM
PREV LONG TERM....JB
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
408 AM CDT SUN JUL 28 2013
.DISCUSSION...
310 AM...FORECAST CONCERNS REMAIN TEMPERATURES TODAY/TONIGHT AND
THEN CONVECTIVE TRENDS/POTENTIAL MONDAY NIGHT INTO NEXT WEEKEND.
CLOUD COVER AND WINDS UP TO 10 MPH HELPING TO KEEP TEMPS IN THE
LOWER/MID 50S MOST AREAS AND WITH CLOUD COVER THICKENING FROM THE
NORTHWEST...TEMPS WILL LIKELY REMAIN FAIRLY STEADY WITH BEST
CHANCE OF ANY UPPER 40S ACROSS THE SOUTHERN HALF OR SO. ANOTHER
POCKET OF COLDER AIR ALOFT WILL ROTATE ACROSS THE AREA THIS
MORNING WITH 850MB TEMPS PERHAPS AS LOW AS +3C. THIS COMBINED WITH
A WEAK WAVE ROTATING THROUGH THE AREA THIS MORNING WILL LIKELY
GENERATE SOME SHOWERS THAT SHOULD DISSIPATE FROM WEST TO EAST BY
EARLY AFTERNOON. SOME WEAK WARM AIR ADVECTION BEGINS LATE THIS
AFTERNOON WITH SOME PARTIAL CLEARING ALSO POSSIBLE BUT NOT SURE
HOW MUCH IMPACT THIS MAY HAVE ON HIGH TEMPS AND STAYED CLOSE TO
GUIDANCE...MID/UPPER 60S WITH PERHAPS A FEW LOCATIONS NEAR 70 FAR
SOUTH. NO CHANGES TO LOWS TONIGHT...GENERALLY UPPER 40S/LOWER 50S.
A WEAK RIDGE OF HIGH PRESSURE WILL BUILD ACROSS THE WESTERN LAKES
TONIGHT AND GRADUALLY SHIFT SOUTHEAST ACROSS THE OHIO VALLEY
MONDAY NIGHT INTO TUESDAY AS WEAK LOW PRESSURE MOVES EAST OUT OF
THE CENTRAL PLAINS TUESDAY. THUS MONDAY IS LOOKING MUCH WARMER...
THOUGH STILL BELOW NORMAL...WITH HIGHS REBOUNDING INTO THE MID TO
PERHAPS UPPER 70S UNDER MOSTLY SUNNY SKIES. THE LIGHT WINDS WILL
LIKELY ALLOW FOR A LAKE BREEZE TO DEVELOP THOUGH SHOULD HAVE A
MINIMAL IMPACT ON TEMPS.
CONFIDENCE THEN BEGINS TO DECREASE MONDAY NIGHT THROUGH MIDWEEK
AS THE LOW MOVING OUT OF THE PLAINS WEAKENS TUESDAY NIGHT WITH A
WEAK COLD FRONT MOVING SOUTH ACROSS THE UPPER MIDWEST AND INTO THE
LAKES REGION WEDNESDAY AFTERNOON/WEDNESDAY NIGHT. THERE WILL BE
SEVERAL DRY HOURS DURING THIS TIME PERIOD...BUT LOW CHANCE POPS
STILL SEEM WARRANTED FROM THIS DISTANCE. BULK OF ANY PRECIP LATE
MONDAY INTO TUESDAY STILL SEEMS TO BE FOCUSED SOUTH OF THE AREA
HOWEVER. PRECIP WITH THE FRONTAL BOUNDARY WEDNESDAY AFTERNOON/
EVENING SEEMS LIMITED WITH ISOLATED COVERAGE POSSIBLE.
ANOTHER WEAK RIDGE SPREADS ACROSS THE AREA THURSDAY WHICH STILL
LOOKS DRY. ANOTHER COLD FRONT/WEAK SURFACE LOW MOVES ACROSS THE
REGION FRIDAY/FRIDAY NIGHT. A BIT EARLY FOR SPECIFICS WITH THIS
ESPECIALLY TIMING...BUT SOME CONSENSUS AMONG THE GFS/ECMWF FOR
CONTINUED COOL NORTHWEST FLOW NEXT WEEKEND WITH AN UPPER LOW NOT
THAT FAR AWAY...ACROSS NORTHERN ONTARIO. CMS
&&
.CLIMATE...
CURRENT RECORD LOWEST HIGH AND LOW TEMPERATURE READINGS FOR
SUN AND SUN OVERNIGHT-MON MORNING...
ROCKFORD CHICAGO
SUN JUL 28TH...
LO 46(1925) 51(1984)
HI 65(1962) 66(1981)
SUN OVERNIGHT/MON JUL 29TH...
LO 47(1925) 50(1984)
TRS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* SCATTERED LIGHT SHOWERS THROUGH MID MORNING.
* LOW POTENTIAL FOR BRIEF MVFR CIGS THIS MORNING.
ALLSOPP
//DISCUSSION...UPDATED 06Z...
UNUSUALLY STRONG AND COLD UPPER LOW CONTINUES TO SPIN OVER THE
WESTERN GREAT LAKES EARLY THIS MORNING. A SHORT WAVE WAS WRAPPING
AROUND THE SOUTHWEST FLANK OF THE LOW ACROSS SOUTHERN WI THIS MORNING.
RADAR SHOWED ONE AREA OF SHOWERS OVER LAKE MI ASSOCIATED WITH THE
UPPER LOW WITH ANOTHER POCKET OF SHOWERS OVER SOUTHWEST
WI...SOUTHEAST MN...NORTHEAST IA...ASSOCIATED WITH THE SHORT WAVE. SHORT
TERM GUIDANCE FROM HRRR DEPICTS THIS AREA OF SHOWERS MOVING ACROSS
NORTHERN IL AROUND DAYBREAK AND INTO NW IN BY MID MORNING. EXPECT
SHOWERS TO BE LIGHT AND VERY SPOTTY BUT HAVE ADDED A VCSH FOR THE
POTENTIAL OF A BRIEF LIGHT SHOWER.
THERE IS CURRENTLY A LARGE BREAK IN THE CLOUD COVER IN ADVANCE OF
THE SHORT WAVE BUT VFR CIGS IN THE RANGE OF 5000-10000 FEET WILL
FILL BACK IN OVER THE NEXT FEW HOURS. CIGS WILL LOWER A BIT IN THE
VICINITY OF THE SHOWERS AND SOME LOCAL MVFR CIGS NOTED IN
OBSERVATIONS OVER WESTERN WI. NOT OUT OF THE QUESTION TO SEE A
BRIEF 2000-3000 FOOT CIG THIS MORNING BUT EXPECT VFR CONDITIONS TO
PREVAIL. AFTER THE SHOWER THREAT PASSES TO THE EAST...EXPECT VFR
CIGS TO CONTINUE THROUGH THE REST OF THE DAY IN THE COOL CYCLONIC
FLOW. A SPOTTY LIGHT SHOWER NOT OUT OF THE QUESTION FOR LATE
MORNING AND AFTERNOON BUT NOT ENOUGH CONFIDENCE TO INCLUDE IN TAFS
BEYOND MID MORNING AT THIS TIME. MAY SEE SOME CLEARING THIS
EVENING AS THE UPPER LOW SLOWLY LIFTS NORTHEAST.
WINDS ARE GENERALLY WESTERLY AROUND 10 KT OR LESS. WINDS MAY BACK
SLIGHTLY TO WSW AHEAD OF THE APPROACHING SHORT WAVE EARLY THIS
MORNING...THEN SHIFT MORE WNW AS THE WAVE PASSES BY MID TO LATE
MORNING THROUGH THE AFTERNOON. EXPECT GUSTS TO AROUND 20 KT MID
MORNING THROUGH THE AFTERNOON.
ALLSOPP
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* LOW TO MEDIUM CONFIDENCE IN A SHOWER AT THE TERMINALS THIS
MORNING.
* MEDIUM TO HIGH CONFIDENCE IN CIGS REMAINING VFR. LOW CONFIDENCE
IN BRIEF MVFR CIG AROUND 2500 FT THIS MORNING.
* HIGH CONFIDENCE IN WIND FORECAST.
ALLSOPP
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...VFR. NO SIG WX.
TUESDAY...VFR. CHC SHRA...SLGT CHC TS.
WEDNESDAY...VFR. CHC TSRA.
THURSDAY...VFR. NO SIG WX.
FRIDAY...VFR. CHC TSRA.
TRS
&&
.MARINE...
135 AM CDT
LOW PRESSURE WILL REMAIN OVER THE GREAT LAKES TODAY BEFORE
WEAKENING AND LIFTING NORTHEAST TONIGHT AND MONDAY. MEANWHILE A
RIDGE OF HIGH PRESSURE FROM MANITOBA TO THE CENTRAL PLAINS WILL
MOVE SOUTHEAST INTO THE OHIO VALLEY AND WESTERN LAKES BY MONDAY.
THIS WEATHER PATTERN WILL CONTINUE TO GENERATE WEST TO NORTHWEST
WINDS GUSTING TO 25 KTS TODAY AND TONIGHT BEFORE WINDS DIMINISH
MONDAY. VERY COLD AIR ALOFT OVER THE WARM WATERS OF LAKE MICHIGAN
WILL RESULT IN SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS TODAY
AND TONIGHT. A FEW WATERSPOUTS ARE POSSIBLE THROUGH THIS
EVENING...MAINLY OVER THE EASTERN SIDE OF THE LAKE. LIGHT
SOUTHERLY WINDS WILL DEVELOP MONDAY NIGHT AND TUESDAY AS THE HIGH
SHIFTS EAST. A WEAK TROF OF LOW PRESSURE WILL MOVE ACROSS THE
WESTERN LAKES WEDNESDAY AND WEDNESDAY NIGHT.
ALLSOPP
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...BEACH HAZARDS STATEMENT...INZ002 UNTIL 10 AM MONDAY.
LM...SMALL CRAFT ADVISORY...LMZ743-LMZ744 UNTIL 10 PM SUNDAY.
SMALL CRAFT ADVISORY...NEARSHORE BURNS HARBOR TO MICHIGAN CITY IN UNTIL 10 AM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
310 AM CDT SUN JUL 28 2013
.DISCUSSION...
310 AM...FORECAST CONCERNS REMAIN TEMPERATURES TODAY/TONIGHT AND
THEN CONVECTIVE TRENDS/POTENTIAL MONDAY NIGHT INTO NEXT WEEKEND.
CLOUD COVER AND WINDS UP TO 10 MPH HELPING TO KEEP TEMPS IN THE
LOWER/MID 50S MOST AREAS AND WITH CLOUD COVER THICKENING FROM THE
NORTHWEST...TEMPS WILL LIKELY REMAIN FAIRLY STEADY WITH BEST
CHANCE OF ANY UPPER 40S ACROSS THE SOUTHERN HALF OR SO. ANOTHER
POCKET OF COLDER AIR ALOFT WILL ROTATE ACROSS THE AREA THIS
MORNING WITH 850MB TEMPS PERHAPS AS LOW AS +3C. THIS COMBINED WITH
A WEAK WAVE ROTATING THROUGH THE AREA THIS MORNING WILL LIKELY
GENERATE SOME SHOWERS THAT SHOULD DISSIPATE FROM WEST TO EAST BY
EARLY AFTERNOON. SOME WEAK WARM AIR ADVECTION BEGINS LATE THIS
AFTERNOON WITH SOME PARTIAL CLEARING ALSO POSSIBLE BUT NOT SURE
HOW MUCH IMPACT THIS MAY HAVE ON HIGH TEMPS AND STAYED CLOSE TO
GUIDANCE...MID/UPPER 60S WITH PERHAPS A FEW LOCATIONS NEAR 70 FAR
SOUTH. NO CHANGES TO LOWS TONIGHT...GENERALLY UPPER 40S/LOWER 50S.
A WEAK RIDGE OF HIGH PRESSURE WILL BUILD ACROSS THE WESTERN LAKES
TONIGHT AND GRADUALLY SHIFT SOUTHEAST ACROSS THE OHIO VALLEY
MONDAY NIGHT INTO TUESDAY AS WEAK LOW PRESSURE MOVES EAST OUT OF
THE CENTRAL PLAINS TUESDAY. THUS MONDAY IS LOOKING MUCH WARMER...
THOUGH STILL BELOW NORMAL...WITH HIGHS REBOUNDING INTO THE MID TO
PERHAPS UPPER 70S UNDER MOSTLY SUNNY SKIES. THE LIGHT WINDS WILL
LIKELY ALLOW FOR A LAKE BREEZE TO DEVELOP THOUGH SHOULD HAVE A
MINIMAL IMPACT ON TEMPS.
CONFIDENCE THEN BEGINS TO DECREASE MONDAY NIGHT THROUGH MIDWEEK
AS THE LOW MOVING OUT OF THE PLAINS WEAKENS TUESDAY NIGHT WITH A
WEAK COLD FRONT MOVING SOUTH ACROSS THE UPPER MIDWEST AND INTO THE
LAKES REGION WEDNESDAY AFTERNOON/WEDNESDAY NIGHT. THERE WILL BE
SEVERAL DRY HOURS DURING THIS TIME PERIOD...BUT LOW CHANCE POPS
STILL SEEM WARRANTED FROM THIS DISTANCE. BULK OF ANY PRECIP LATE
MONDAY INTO TUESDAY STILL SEEMS TO BE FOCUSED SOUTH OF THE AREA
HOWEVER. PRECIP WITH THE FRONTAL BOUNDARY WEDNESDAY AFTERNOON/
EVENING SEEMS LIMITED WITH ISOLATED COVERAGE POSSIBLE.
ANOTHER WEAK RIDGE SPREADS ACROSS THE AREA THURSDAY WHICH STILL
LOOKS DRY. ANOTHER COLD FRONT/WEAK SURFACE LOW MOVES ACROSS THE
REGION FRIDAY/FRIDAY NIGHT. A BIT EARLY FOR SPECIFICS WITH THIS
ESPECIALLY TIMING...BUT SOME CONSENSUS AMONG THE GFS/ECMWF FOR
CONTINUED COOL NORTHWEST FLOW NEXT WEEKEND WITH AN UPPER LOW NOT
THAT FAR AWAY...ACROSS NORTHERN ONTARIO. CMS
&&
.CLIMATE...
CURRENT RECORD LOWEST HIGH AND LOW TEMPERATURE READINGS FOR
SUN AND SUN OVERNIGHT-MON MORNING...
ROCKFORD CHICAGO
SUN JUL 28TH...
LO 46(1925) 51(1984)
HI 65(1962) 66(1981)
SUN OVERNIGHT/MON JUL 29TH...
LO 47(1925) 50(1984)
TRS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* POTENTIAL FOR SCATTERED LIGHT SHOWERS AND BRIEF MVFR CIGS 11Z-15Z.
ALLSOPP
//DISCUSSION...UPDATED 06Z...
UNUSUALLY STRONG AND COLD UPPER LOW CONTINUES TO SPIN OVER THE
WESTERN GREAT LAKES EARLY THIS MORNING. A SHORT WAVE WAS WRAPPING
AROUND THE SOUTHWEST FLANK OF THE LOW ACROSS SOUTHERN WI THIS MORNING.
RADAR SHOWED ONE AREA OF SHOWERS OVER LAKE MI ASSOCIATED WITH THE
UPPER LOW WITH ANOTHER POCKET OF SHOWERS OVER SOUTHWEST
WI...SOUTHEAST MN...NORTHEAST IA...ASSOCIATED WITH THE SHORT WAVE. SHORT
TERM GUIDANCE FROM HRRR DEPICTS THIS AREA OF SHOWERS MOVING ACROSS
NORTHERN IL AROUND DAYBREAK AND INTO NW IN BY MID MORNING. EXPECT
SHOWERS TO BE LIGHT AND VERY SPOTTY BUT HAVE ADDED A VCSH FOR THE
POTENTIAL OF A BRIEF LIGHT SHOWER.
THERE IS CURRENTLY A LARGE BREAK IN THE CLOUD COVER IN ADVANCE OF
THE SHORT WAVE BUT VFR CIGS IN THE RANGE OF 5000-10000 FEET WILL
FILL BACK IN OVER THE NEXT FEW HOURS. CIGS WILL LOWER A BIT IN THE
VICINITY OF THE SHOWERS AND SOME LOCAL MVFR CIGS NOTED IN
OBSERVATIONS OVER WESTERN WI. NOT OUT OF THE QUESTION TO SEE A
BRIEF 2000-3000 FOOT CIG THIS MORNING BUT EXPECT VFR CONDITIONS TO
PREVAIL. AFTER THE SHOWER THREAT PASSES TO THE EAST...EXPECT VFR
CIGS TO CONTINUE THROUGH THE REST OF THE DAY IN THE COOL CYCLONIC
FLOW. A SPOTTY LIGHT SHOWER NOT OUT OF THE QUESTION FOR LATE
MORNING AND AFTERNOON BUT NOT ENOUGH CONFIDENCE TO INCLUDE IN TAFS
BEYOND MID MORNING AT THIS TIME. MAY SEE SOME CLEARING THIS
EVENING AS THE UPPER LOW SLOWLY LIFTS NORTHEAST.
WINDS ARE GENERALLY WESTERLY AROUND 10 KT OR LESS. WINDS MAY BACK
SLIGHTLY TO WSW AHEAD OF THE APPROACHING SHORT WAVE EARLY THIS
MORNING...THEN SHIFT MORE WNW AS THE WAVE PASSES BY MID TO LATE
MORNING THROUGH THE AFTERNOON. EXPECT GUSTS TO AROUND 20 KT MID
MORNING THROUGH THE AFTERNOON.
ALLSOPP
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* LOW CONFIDENCE IN SHOWERS OR MVFR CIGS AT TERMINALS THIS MORNING.
* MEDIUM TO HIGH CONFIDENCE IN WIND FORECAST. DIRECTION MAY VARY
BETWEEN 250 AND 290.
ALLSOPP
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...VFR. NO SIG WX.
TUESDAY...VFR. CHC SHRA...SLGT CHC TS.
WEDNESDAY...VFR. CHC TSRA.
THURSDAY...VFR. NO SIG WX.
FRIDAY...VFR. CHC TSRA.
TRS
&&
.MARINE...
135 AM CDT
LOW PRESSURE WILL REMAIN OVER THE GREAT LAKES TODAY BEFORE
WEAKENING AND LIFTING NORTHEAST TONIGHT AND MONDAY. MEANWHILE A
RIDGE OF HIGH PRESSURE FROM MANITOBA TO THE CENTRAL PLAINS WILL
MOVE SOUTHEAST INTO THE OHIO VALLEY AND WESTERN LAKES BY MONDAY.
THIS WEATHER PATTERN WILL CONTINUE TO GENERATE WEST TO NORTHWEST
WINDS GUSTING TO 25 KTS TODAY AND TONIGHT BEFORE WINDS DIMINISH
MONDAY. VERY COLD AIR ALOFT OVER THE WARM WATERS OF LAKE MICHIGAN
WILL RESULT IN SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS TODAY
AND TONIGHT. A FEW WATERSPOUTS ARE POSSIBLE THROUGH THIS
EVENING...MAINLY OVER THE EASTERN SIDE OF THE LAKE. LIGHT
SOUTHERLY WINDS WILL DEVELOP MONDAY NIGHT AND TUESDAY AS THE HIGH
SHIFTS EAST. A WEAK TROF OF LOW PRESSURE WILL MOVE ACROSS THE
WESTERN LAKES WEDNESDAY AND WEDNESDAY NIGHT.
ALLSOPP
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...BEACH HAZARDS STATEMENT...INZ001 UNTIL 10 PM SUNDAY.
BEACH HAZARDS STATEMENT...INZ002 UNTIL 10 AM MONDAY.
LM...SMALL CRAFT ADVISORY...LMZ743-LMZ744 UNTIL 10 PM SUNDAY.
SMALL CRAFT ADVISORY...NEARSHORE BURNS HARBOR TO MICHIGAN CITY
IN UNTIL 10 AM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS LINCOLN IL
301 AM CDT SUN JUL 28 2013
.DISCUSSION...
ISSUED 301 AM CDT SUN JUL 28 2013
SHORT TERM...TODAY THROUGH TUESDAY
MID-SEPTEMBER LEVEL TEMPERATURES CONTINUE TO DOMINATE THE REGION
EARLY THIS MORNING. 2 AM SURFACE MAP SHOWED CANADIAN HIGH PRESSURE
STRETCHING DOWN THE PLAINS...THEN NOSING EAST TOWARDS THE
TENNESSEE VALLEY. ALOFT A DEEP CLOSED LOW WAS CENTERED OVER
EASTERN WI AND A VORT LOBE ROTATING AROUND THE BACK SIDE OF THIS
FEATURE WAS PRODUCING A LARGE SWATH OF STRATO-CU AND SCATTERED
SHOWERS OVER NE IA...NORTHERN IL...AND SOUTHERN WI. A SECONDARY
COLD FRONT EMBEDDED IN THIS REGION WAS HELPING DRIVE THE SHOWERS.
THIS SHORTWAVE AND ASSOCIATED FRONT ARE EXPECTED TO ROTATE
SOUTHEAST TODAY AND BRUSH THE NORTHEAST CWA WITH A PERIOD OF
CLOUDS AND POSSIBLY AN ISOLATED SHOWER OR SPRINKLE THIS MORNING.
OTHERWISE DIURNAL CU WILL BE MOST NUMEROUS IN THE NORTHERN CWA
THROUGH AFTERNOON. THE AIRMASS SHOWS LITTLE CHANGE FROM YESTERDAY
WITH 850MB TEMPS ONLY ABOUT 1 DEGREE WARMER. THEREFORE BASED HIGHS
ON PERSISTENCE PLUS A DEGREE OR TWO...AND THIS PUTS RECORD LOW
HIGHS IN REACH ONCE AGAIN. TONIGHT...CLEAR SKIES AND CALM WINDS
UNDER THE RIDGE AXIS WILL PROMOTE ANOTHER NIGHT OF GOOD RADIATIONAL
COOLING AND LOWS AGAIN WILL BE IN RECORD TERRITORY IN THE LOWER
50S. SEE CLIMATE SECTION BELOW FOR SPECIFIC NUMBERS.
MONDAY AND TUESDAY...A REGION OF LOW PRESSURE OVER THE PLAINS DEVELOPS A
WARM FRONT EAST INTO MISSOURI WITH STRONG ISENTROPIC LIFT PUSHING
SCATTERED SHOWERS AND STORMS INTO EASTERN MISSOURI AND WESTERN IL
BY EVENING. 00Z NAM IS MOST AGGRESSIVE BRINGING PRECIP INTO THE
WESTERN CWA DURING THE AFTERNOON. FEEL LINGERING EFFECTS OF
RIDGING AND ASSOCIATED DRY AIR WILL ERODE LEADING EDGE OF PRECIP
AND HAVE LIMITED POPS TO SLIGHT CHANCE OVER THE FAR SOUTHWEST CWA.
POPS GRADUALLY INCREASE FROM THE WEST OVERNIGHT AS THE WARM FRONT
EDGES EAST ALONG WITH AN INVERTED TROF OF LOW PRESSURE. INCREASING
LIFT AND MOISTURE ADVECTION SHOULD BRING A FEW ROUNDS OF SHOWERS
AND STORMS TO AT LEAST SOUTHERN THE CWA LATE OVERNIGHT...AND
ESPECIALLY DURING THE DAY TUESDAY. STILL HAVE LIKELY POPS FOCUSED
SOUTH OF A JACKSONVILLE TO MATTOON LINE WHERE GUIDANCE SUPPORTS
BEST LIFT IN REGION OF PRECIPITABLE WATER NEAR 2 INCHES. 1-2 INCH
TOTALS LOOK POSSIBLE FOR THE SOUTHERN THIRD OF THE CWA.
LONG TERM...WEDNESDAY THROUGH SATURDAY
THERE IS SOME QUESTION HOW QUICKLY PRECIP WILL END TUESDAY
NIGHT/WEDNESDAY AS AN UPPER TROF AND FRONT IS NOW SHOWN SHIFTING
ACROSS THE UPPER MIDWEST AND GREAT LAKES ON WEDNESDAY. AS A RESULT
HAVE KEPT LOW CHANCE POPS GOING FOR LIGHT QPF ACROSS THE CENTRAL AND
EASTERN CWA.
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT APPEAR DRY AS A REGION OF
HIGH PRESSURE MOVES ACROSS THE AREA AND LOW AMPLITUDE WNW FLOW
SETS UP ALOFT. THIS SHOULD ALLOW FOR THERMAL MODERATION AND
TEMPERATURES UP CLOSER TO...BUT STILL A FEW DEGREES BELOW NORMAL.
MEDIUM RANGE MODELS CONTINUE TO ADVERTISE A SIGNIFICANT WAVE
LIFTING OUT OF THE CENTRAL ROCKIES LATE-WEEK WITH A GOOD SOUTHERLY
FETCH FOR MOISTURE TRANSPORT AHEAD OF THIS FEATURE. 00Z GUIDANCE
FOCUSES THE OVERRUNNING PRECIP WELL NORTHWEST OF THE LOCAL AREA
LATE THURSDAY...GRADUALLY SHIFTING SOUTHEAST WITH A LOW PRESSURE
WAVE AND COLD FRONT FRIDAY INTO SATURDAY. USUAL TIMING DIFFERENCES
AT THIS RANGE AMONG THE MODELS WITH THE FAVORED ECMWF ABOUT 12
HOURS SLOWER...FOCUSING MOST PRECIP FRIDAY NIGHT INTO SATURDAY.
25
&&
.AVIATION...
ISSUED 1140 PM CDT SAT JUL 27 2013
SCATTERED TO BROKEN CLOUDS AROUND 7000 FEET WERE TRACKING THROUGH
KPIA AND KBMI LATE SATURDAY EVENING...ASSOCIATED WITH THE LARGE
UPPER LOW SPINNING OVER WISCONSIN. RAP MODEL GUIDANCE SUGGESTS NOT
TOO MUCH FURTHER SOUTH PROGRESS THE REMAINDER OF THE NIGHT...
GENERALLY FOLLOWING WEAK DISTURBANCES ROTATING THROUGH THE FLOW.
AS SUCH...WILL LIMIT ANY CEILINGS TO THE KPIA-KCMI CORRIDOR FOR
NOW...AND JUST MENTION SCATTERED CLOUDS ELSEWHERE. GUSTY WEST
WINDS EXPECTED TO DEVELOP AGAIN LATE SUNDAY MORNING...ALONG WITH
ADDITIONAL DIURNAL CUMULUS. AS THE UPPER LOW PULLS AWAY LATE
SUNDAY...THE CLOUDS WILL FADE AGAIN TOWARD SUNSET...AND WINDS
BECOME LIGHT DUE TO A NARROW AXIS OF HIGH PRESSURE EXTENDING
NORTHWEST INTO IOWA.
GEELHART
&&
.CLIMATE...
ISSUED 301 AM CDT SUN JUL 28 2013
RECORD COOL HIGHS FOR JULY 28
LINCOLN.......70 IN 1907
PEORIA........72 IN 1987
SPRINGFIELD...70 IN 1907
RECORD LOWS FOR JULY 29
LINCOLN.......47 IN 1925
PEORIA........50 IN 1971
SPRINGFIELD...52 IN 1971
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
148 AM CDT SUN JUL 28 2013
.DISCUSSION...
310 PM CDT
SHORT TERM...TONIGHT THROUGH MONDAY
PRIMARY FORECAST CONCERN CONTINUES TO BE WITH TEMPERATURES IN THIS
TASTE OF FALL WE WILL CONTINUE TO EXPERIENCE THROUGH THE WEEKEND.
CONTINUED COOL ADVECTION AROUND DEEPENING AND EXTREMELY ANOMALOUS
CLOSED LOW OVER THE NORTHWESTERN LAKES AND RESULTANT BLOSSOMING OF
STRATOCU DECK PREVENTED MUCH OF A CLIMB IN TEMPERATURES THIS
AFTERNOON AND THUS RECORD LOW MAX TEMPS FOR THE DATE WERE SET FOR
BOTH OF OUR PRIMARY CLIMATE SITES. THE +2 850 MB TEMP SAMPLED AT MSP
THIS MORNING ADVECTED TOWARD THE AREA IN COLD NORTHWESTERLY FLOW.
STRONG WAVE NOTED ON AFTERNOON W/V IMAGERY OVER THE UPPER
MISSISSIPPI VALLEY WRAPPING SOUTH AROUND THE LOW WILL SPREAD CLOUD
COVER INTO THE AREA TONIGHT SO LOW TEMPERATURES WILL LIKELY BE
WARMER THAN THEY WOULD HAVE BEEN WITH CLEAR OR PARTLY CLOUDY SKIES.
THE BEST CHANCE FOR SEEING UPPER 40S WILL BE ACROSS CENTRAL IL AND
INDIANA FARTHER SOUTH OF THE TRAJECTORY OF THE VORT MAX.
ELSEWHERE...BUMPED UP LOW TEMPS TO THE LOWER AND MID 50S. ALSO ADDED
A CHANCE FOR SHRA MAINLY NORTH OF I-80 THIS EVENING...WITH SHOWERS
NOTED ON LEADING EDGE OF WAVE ACROSS SOUTHEAST MN AND FAR NE IA.
ON SUNDAY...LOW LEVEL THERMAL PROFILES WILL BE ONLY SLIGHTLY WARMER
THAN TODAY AND AGAIN EXPECT A BLOSSOMING OF STRATOCU MID SUNDAY
MORNING. HAVE FORECAST HIGHS MAINLY IN MID AND UPPER 60S...SO WE
COULD BE LOOKING AT ANOTHER DAY FLIRTING WITH RECORD
LOW MAX TEMPS. GIVEN LACK OF SHRA OVER CWA TODAY...HAVE CONFINED
SLIGHT CHANCE FOR DIURNALLY DRIVEN SHRA/SPRINKLES FOR NORTHEAST 1/3
OF CWA. HIGH PRESSURE SPREADING OVERHEAD SUNDAY NIGHT YIELDING
LIGHTER WINDS AND CLEARING OF LINGERING CLOUD COVER WILL LIKELY SET
THE STAGE FOR THE COOLEST NIGHT OF THIS COOL WAVE ON SUNDAY
NIGHT...WITH MID 40S (!) POSSIBLE IN TYPICALLY COLDER RURAL
LOCATIONS. THINK THAT IF BOUNDARY LAYER DECOUPLES...RADIATIONAL
COOLING WILL OFFSET SLOW WARMING TREND ALOFT.
MONDAY WILL FINALLY START THE WARMING TREND WITH CONTINUED WARMING
TEMPS ALOFT BUT BEST WAA HOLDING OFF UNTIL THE EVENING AND MORE
LIMITED MIXING UNDER THE RIDGE AXIS MEANS THAT HIGHS SHOULD STILL
ONLY BE ABLE TO REACH MID TO PERHAPS UPPER 70S.
GUIDANCE BEGINS TO DIVERGE AS UPPER LEVEL LOW DEPARTS MONDAY NIGHT
INTO TUESDAY AND ZONAL FLOW PATTERN DEVELOPS ALOFT. A WAVE
APPROACHING FROM THE WEST COULD BRING A SLIGHT CHANCE OF A SHOWER TO
THE SOUTHWEST 1/3 OF CWA BY EARLY TUES BUT WEAK LOW LEVEL JET AND
LIMITED TO NON-EXISTENT MOISTURE RETURN AND INSTABILITY WILL KEEP
CHANCES LOW. LIMITED MOISTURE RETURN WILL KEEP INSTABILITY LOW ON
TUESDAY...WITH THE MODELS RANGING FROM A COMPACT VORT PUSHING ACROSS
CENTRAL IL OR A SPLIT WAVE SET-UP WITH ONE ALONG AND NORTH OF FAR
NORTHERN CWA AND SECOND WAVE TO SOUTH. KEPT LOW POPS FOR SHRA AND
ONLY A SLIGHT CHANCE FOR TSRA DUE TO VERY LIMITED INSTABILITY BUT
WHICHEVER SCENARIO PANS OUT WILL DICTATE CLOUD COVER AND HIGH
TEMPERATURES. IF THERE IS LESS CLOUD COVER...ESPECIALLY
NORTH...CURRENT FORECAST HIGHS WILL LIKELY BE TOO LOW BASED ON UPPER
AIR CLIMATOLOGY.
LONG TERM...TUESDAY NIGHT THROUGH FRIDAY
CONFIDENCE IS LOW IN THE TUESDAY NIGHT PERIOD DUE TO AFOREMENTIONED
MODEL DIFFERENCES WITH TWO SHORTWAVES PASSING THROUGH THE
REGION...SO MAINTAINED LOW CHANCE POPS. WEDNESDAY APPEARS TO OFFER A
SHOT AT SOME ADDITIONAL SHRA/TSRA WITH A COLD FRONT PUSHING THROUGH
THE AREA...THOUGH EARLIER FROPA COULD LIMIT THUNDER CHANCES. ON
THURSDAY...HIGH PRESSURE AND DRIER NORTHWEST FLOW ALOFT LOOKS LIKE
THE MOST LIKELY CANDIDATE FOR A DRY FORECAST. THERE IS THEN DECENT
AGREEMENT ON A POTENTIALLY MORE ACTIVE PATTERN FRIDAY INTO SATURDAY
WITH FASTER WNW FLOW ALOFT AROUND CENTRAL CONUS RIDGING...SO
MAINTAINED MID RANGE CHANCE POPS FROM GUIDANCE BLEND. TEMPERATURES
IN THE EXTENDED LOOK TO RETURN CLOSER TO NORMAL. THE 12Z GFS
SUGGESTED A BIG WARM UP ON FRIDAY WITH 850 MB TEMPS WARMING TO
AROUND +20 BUT THE LATEST ECMWF IS MORE MUTED IN WARM ADVECTION
FRIDAY AND GFS ENSEMBLE SUGGESTS A GOOD DEAL OF SPREAD IN THE
TEMPERATURE FORECAST ON FRIDAY.
RC
&&
.CLIMATE...
CURRENT RECORD LOWEST HIGH AND LOW TEMPERATURE READINGS FOR
SUN AND SUN OVERNIGHT-MON MORNING...
ROCKFORD CHICAGO
SUN JUL 28TH...
LO 46(1925) 51(1984)
HI 65(1962) 66(1981)
SUN OVERNIGHT/MON JUL 29TH...
LO 47(1925) 50(1984)
TRS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* POTENTIAL FOR SCATTERED LIGHT SHOWERS AND BRIEF MVFR CIGS 11Z-15Z.
ALLSOPP
//DISCUSSION...UPDATED 06Z...
UNUSUALLY STRONG AND COLD UPPER LOW CONTINUES TO SPIN OVER THE
WESTERN GREAT LAKES EARLY THIS MORNING. A SHORT WAVE WAS WRAPPING
AROUND THE SOUTHWEST FLANK OF THE LOW ACROSS SOUTHERN WI THIS MORNING.
RADAR SHOWED ONE AREA OF SHOWERS OVER LAKE MI ASSOCIATED WITH THE
UPPER LOW WITH ANOTHER POCKET OF SHOWERS OVER SOUTHWEST
WI...SOUTHEAST MN...NORTHEAST IA...ASSOCIATED WITH THE SHORT WAVE. SHORT
TERM GUIDANCE FROM HRRR DEPICTS THIS AREA OF SHOWERS MOVING ACROSS
NORTHERN IL AROUND DAYBREAK AND INTO NW IN BY MID MORNING. EXPECT
SHOWERS TO BE LIGHT AND VERY SPOTTY BUT HAVE ADDED A VCSH FOR THE
POTENTIAL OF A BRIEF LIGHT SHOWER.
THERE IS CURRENTLY A LARGE BREAK IN THE CLOUD COVER IN ADVANCE OF
THE SHORT WAVE BUT VFR CIGS IN THE RANGE OF 5000-10000 FEET WILL
FILL BACK IN OVER THE NEXT FEW HOURS. CIGS WILL LOWER A BIT IN THE
VICINITY OF THE SHOWERS AND SOME LOCAL MVFR CIGS NOTED IN
OBSERVATIONS OVER WESTERN WI. NOT OUT OF THE QUESTION TO SEE A
BRIEF 2000-3000 FOOT CIG THIS MORNING BUT EXPECT VFR CONDITIONS TO
PREVAIL. AFTER THE SHOWER THREAT PASSES TO THE EAST...EXPECT VFR
CIGS TO CONTINUE THROUGH THE REST OF THE DAY IN THE COOL CYCLONIC
FLOW. A SPOTTY LIGHT SHOWER NOT OUT OF THE QUESTION FOR LATE
MORNING AND AFTERNOON BUT NOT ENOUGH CONFIDENCE TO INCLUDE IN TAFS
BEYOND MID MORNING AT THIS TIME. MAY SEE SOME CLEARING THIS
EVENING AS THE UPPER LOW SLOWLY LIFTS NORTHEAST.
WINDS ARE GENERALLY WESTERLY AROUND 10 KT OR LESS. WINDS MAY BACK
SLIGHTLY TO WSW AHEAD OF THE APPROACHING SHORT WAVE EARLY THIS
MORNING...THEN SHIFT MORE WNW AS THE WAVE PASSES BY MID TO LATE
MORNING THROUGH THE AFTERNOON. EXPECT GUSTS TO AROUND 20 KT MID
MORNING THROUGH THE AFTERNOON.
ALLSOPP
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* LOW CONFIDENCE IN SHOWERS OR MVFR CIGS AT TERMINALS THIS MORNING.
* MEDIUM TO HIGH CONFIDENCE IN WIND FORECAST. DIRECTION MAY VARY
BETWEEN 250 AND 290.
ALLSOPP
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...VFR. NO SIG WX.
TUESDAY...VFR. CHC SHRA...SLGT CHC TS.
WEDNESDAY...VFR. CHC TSRA.
THURSDAY...VFR. NO SIG WX.
FRIDAY...VFR. CHC TSRA.
TRS
&&
.MARINE...
135 AM CDT
LOW PRESSURE WILL REMAIN OVER THE GREAT LAKES TODAY BEFORE
WEAKENING AND LIFTING NORTHEAST TONIGHT AND MONDAY. MEANWHILE A
RIDGE OF HIGH PRESSURE FROM MANITOBA TO THE CENTRAL PLAINS WILL
MOVE SOUTHEAST INTO THE OHIO VALLEY AND WESTERN LAKES BY MONDAY.
THIS WEATHER PATTERN WILL CONTINUE TO GENERATE WEST TO NORTHWEST
WINDS GUSTING TO 25 KTS TODAY AND TONIGHT BEFORE WINDS DIMINISH
MONDAY. VERY COLD AIR ALOFT OVER THE WARM WATERS OF LAKE MICHIGAN
WILL RESULT IN SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS TODAY
AND TONIGHT. A FEW WATERSPOUTS ARE POSSIBLE THROUGH THIS
EVENING...MAINLY OVER THE EASTERN SIDE OF THE LAKE. LIGHT
SOUTHERLY WINDS WILL DEVELOP MONDAY NIGHT AND TUESDAY AS THE HIGH
SHIFTS EAST. A WEAK TROF OF LOW PRESSURE WILL MOVE ACROSS THE
WESTERN LAKES WEDNESDAY AND WEDNESDAY NIGHT.
ALLSOPP
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...BEACH HAZARDS STATEMENT...INZ001 UNTIL 10 PM SUNDAY.
BEACH HAZARDS STATEMENT...INZ002 UNTIL 10 AM MONDAY.
LM...SMALL CRAFT ADVISORY...LMZ743-LMZ744 UNTIL 10 PM SUNDAY.
SMALL CRAFT ADVISORY...NEARSHORE BURNS HARBOR TO MICHIGAN CITY IN UNTIL 10 AM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1238 AM CDT SUN JUL 28 2013
.DISCUSSION...
310 PM CDT
SHORT TERM...TONIGHT THROUGH MONDAY
PRIMARY FORECAST CONCERN CONTINUES TO BE WITH TEMPERATURES IN THIS
TASTE OF FALL WE WILL CONTINUE TO EXPERIENCE THROUGH THE WEEKEND.
CONTINUED COOL ADVECTION AROUND DEEPENING AND EXTREMELY ANOMALOUS
CLOSED LOW OVER THE NORTHWESTERN LAKES AND RESULTANT BLOSSOMING OF
STRATOCU DECK PREVENTED MUCH OF A CLIMB IN TEMPERATURES THIS
AFTERNOON AND THUS RECORD LOW MAX TEMPS FOR THE DATE WERE SET FOR
BOTH OF OUR PRIMARY CLIMATE SITES. THE +2 850 MB TEMP SAMPLED AT MSP
THIS MORNING ADVECTED TOWARD THE AREA IN COLD NORTHWESTERLY FLOW.
STRONG WAVE NOTED ON AFTERNOON W/V IMAGERY OVER THE UPPER
MISSISSIPPI VALLEY WRAPPING SOUTH AROUND THE LOW WILL SPREAD CLOUD
COVER INTO THE AREA TONIGHT SO LOW TEMPERATURES WILL LIKELY BE
WARMER THAN THEY WOULD HAVE BEEN WITH CLEAR OR PARTLY CLOUDY SKIES.
THE BEST CHANCE FOR SEEING UPPER 40S WILL BE ACROSS CENTRAL IL AND
INDIANA FARTHER SOUTH OF THE TRAJECTORY OF THE VORT MAX.
ELSEWHERE...BUMPED UP LOW TEMPS TO THE LOWER AND MID 50S. ALSO ADDED
A CHANCE FOR SHRA MAINLY NORTH OF I-80 THIS EVENING...WITH SHOWERS
NOTED ON LEADING EDGE OF WAVE ACROSS SOUTHEAST MN AND FAR NE IA.
ON SUNDAY...LOW LEVEL THERMAL PROFILES WILL BE ONLY SLIGHTLY WARMER
THAN TODAY AND AGAIN EXPECT A BLOSSOMING OF STRATOCU MID SUNDAY
MORNING. HAVE FORECAST HIGHS MAINLY IN MID AND UPPER 60S...SO WE
COULD BE LOOKING AT ANOTHER DAY FLIRTING WITH RECORD
LOW MAX TEMPS. GIVEN LACK OF SHRA OVER CWA TODAY...HAVE CONFINED
SLIGHT CHANCE FOR DIURNALLY DRIVEN SHRA/SPRINKLES FOR NORTHEAST 1/3
OF CWA. HIGH PRESSURE SPREADING OVERHEAD SUNDAY NIGHT YIELDING
LIGHTER WINDS AND CLEARING OF LINGERING CLOUD COVER WILL LIKELY SET
THE STAGE FOR THE COOLEST NIGHT OF THIS COOL WAVE ON SUNDAY
NIGHT...WITH MID 40S (!) POSSIBLE IN TYPICALLY COLDER RURAL
LOCATIONS. THINK THAT IF BOUNDARY LAYER DECOUPLES...RADIATIONAL
COOLING WILL OFFSET SLOW WARMING TREND ALOFT.
MONDAY WILL FINALLY START THE WARMING TREND WITH CONTINUED WARMING
TEMPS ALOFT BUT BEST WAA HOLDING OFF UNTIL THE EVENING AND MORE
LIMITED MIXING UNDER THE RIDGE AXIS MEANS THAT HIGHS SHOULD STILL
ONLY BE ABLE TO REACH MID TO PERHAPS UPPER 70S.
GUIDANCE BEGINS TO DIVERGE AS UPPER LEVEL LOW DEPARTS MONDAY NIGHT
INTO TUESDAY AND ZONAL FLOW PATTERN DEVELOPS ALOFT. A WAVE
APPROACHING FROM THE WEST COULD BRING A SLIGHT CHANCE OF A SHOWER TO
THE SOUTHWEST 1/3 OF CWA BY EARLY TUES BUT WEAK LOW LEVEL JET AND
LIMITED TO NON-EXISTENT MOISTURE RETURN AND INSTABILITY WILL KEEP
CHANCES LOW. LIMITED MOISTURE RETURN WILL KEEP INSTABILITY LOW ON
TUESDAY...WITH THE MODELS RANGING FROM A COMPACT VORT PUSHING ACROSS
CENTRAL IL OR A SPLIT WAVE SET-UP WITH ONE ALONG AND NORTH OF FAR
NORTHERN CWA AND SECOND WAVE TO SOUTH. KEPT LOW POPS FOR SHRA AND
ONLY A SLIGHT CHANCE FOR TSRA DUE TO VERY LIMITED INSTABILITY BUT
WHICHEVER SCENARIO PANS OUT WILL DICTATE CLOUD COVER AND HIGH
TEMPERATURES. IF THERE IS LESS CLOUD COVER...ESPECIALLY
NORTH...CURRENT FORECAST HIGHS WILL LIKELY BE TOO LOW BASED ON UPPER
AIR CLIMATOLOGY.
LONG TERM...TUESDAY NIGHT THROUGH FRIDAY
CONFIDENCE IS LOW IN THE TUESDAY NIGHT PERIOD DUE TO AFOREMENTIONED
MODEL DIFFERENCES WITH TWO SHORTWAVES PASSING THROUGH THE
REGION...SO MAINTAINED LOW CHANCE POPS. WEDNESDAY APPEARS TO OFFER A
SHOT AT SOME ADDITIONAL SHRA/TSRA WITH A COLD FRONT PUSHING THROUGH
THE AREA...THOUGH EARLIER FROPA COULD LIMIT THUNDER CHANCES. ON
THURSDAY...HIGH PRESSURE AND DRIER NORTHWEST FLOW ALOFT LOOKS LIKE
THE MOST LIKELY CANDIDATE FOR A DRY FORECAST. THERE IS THEN DECENT
AGREEMENT ON A POTENTIALLY MORE ACTIVE PATTERN FRIDAY INTO SATURDAY
WITH FASTER WNW FLOW ALOFT AROUND CENTRAL CONUS RIDGING...SO
MAINTAINED MID RANGE CHANCE POPS FROM GUIDANCE BLEND. TEMPERATURES
IN THE EXTENDED LOOK TO RETURN CLOSER TO NORMAL. THE 12Z GFS
SUGGESTED A BIG WARM UP ON FRIDAY WITH 850 MB TEMPS WARMING TO
AROUND +20 BUT THE LATEST ECMWF IS MORE MUTED IN WARM ADVECTION
FRIDAY AND GFS ENSEMBLE SUGGESTS A GOOD DEAL OF SPREAD IN THE
TEMPERATURE FORECAST ON FRIDAY.
RC
&&
.CLIMATE...
CURRENT RECORD LOWEST HIGH AND LOW TEMPERATURE READINGS FOR
SUN AND SUN OVERNIGHT-MON MORNING...
ROCKFORD CHICAGO
SUN JUL 28TH...
LO 46(1925) 51(1984)
HI 65(1962) 66(1981)
SUN OVERNIGHT/MON JUL 29TH...
LO 47(1925) 50(1984)
TRS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* POTENTIAL FOR SCATTERED LIGHT SHOWERS AND BRIEF MVFR CIGS 11Z-15Z.
ALLSOPP
//DISCUSSION...UPDATED 06Z...
UNUSUALLY STRONG AND COLD UPPER LOW CONTINUES TO SPIN OVER THE
WESTERN GREAT LAKES EARLY THIS MORNING. A SHORT WAVE WAS WRAPPING
AROUND THE SOUTHWEST FLANK OF THE LOW ACROSS SOUTHERN WI THIS MORNING.
RADAR SHOWED ONE AREA OF SHOWERS OVER LAKE MI ASSOCIATED WITH THE
UPPER LOW WITH ANOTHER POCKET OF SHOWERS OVER SOUTHWEST
WI...SOUTHEAST MN...NORTHEAST IA...ASSOCIATED WITH THE SHORT WAVE. SHORT
TERM GUIDANCE FROM HRRR DEPICTS THIS AREA OF SHOWERS MOVING ACROSS
NORTHERN IL AROUND DAYBREAK AND INTO NW IN BY MID MORNING. EXPECT
SHOWERS TO BE LIGHT AND VERY SPOTTY BUT HAVE ADDED A VCSH FOR THE
POTENTIAL OF A BRIEF LIGHT SHOWER.
THERE IS CURRENTLY A LARGE BREAK IN THE CLOUD COVER IN ADVANCE OF
THE SHORT WAVE BUT VFR CIGS IN THE RANGE OF 5000-10000 FEET WILL
FILL BACK IN OVER THE NEXT FEW HOURS. CIGS WILL LOWER A BIT IN THE
VICINITY OF THE SHOWERS AND SOME LOCAL MVFR CIGS NOTED IN
OBSERVATIONS OVER WESTERN WI. NOT OUT OF THE QUESTION TO SEE A
BRIEF 2000-3000 FOOT CIG THIS MORNING BUT EXPECT VFR CONDITIONS TO
PREVAIL. AFTER THE SHOWER THREAT PASSES TO THE EAST...EXPECT VFR
CIGS TO CONTINUE THROUGH THE REST OF THE DAY IN THE COOL CYCLONIC
FLOW. A SPOTTY LIGHT SHOWER NOT OUT OF THE QUESTION FOR LATE
MORNING AND AFTERNOON BUT NOT ENOUGH CONFIDENCE TO INCLUDE IN TAFS
BEYOND MID MORNING AT THIS TIME. MAY SEE SOME CLEARING THIS
EVENING AS THE UPPER LOW SLOWLY LIFTS NORTHEAST.
WINDS ARE GENERALLY WESTERLY AROUND 10 KT OR LESS. WINDS MAY BACK
SLIGHTLY TO WSW AHEAD OF THE APPROACHING SHORT WAVE EARLY THIS
MORNING...THEN SHIFT MORE WNW AS THE WAVE PASSES BY MID TO LATE
MORNING THROUGH THE AFTERNOON. EXPECT GUSTS TO AROUND 20 KT MID
MORNING THROUGH THE AFTERNOON.
ALLSOPP
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* LOW CONFIDENCE IN SHOWERS OR MVFR CIGS AT TERMINALS THIS MORNING.
* MEDIUM TO HIGH CONFIDENCE IN WIND FORECAST. DIRECTION MAY VARY
BETWEEN 250 AND 290.
ALLSOPP
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...VFR. NO SIG WX.
TUESDAY...VFR. CHC SHRA...SLGT CHC TS.
WEDNESDAY...VFR. CHC TSRA.
THURSDAY...VFR. NO SIG WX.
FRIDAY...VFR. CHC TSRA.
TRS
&&
.MARINE...
240 PM CDT
LOW PRESSURE WILL CONTINUE TO SPIN OVER THE GREAT LAKES WITH AN
UNSEASONABLY STRONG PUSH OF COLD AIR INTO THE REGION. MODERATELY
STRONG NORTHWEST WINDS TO AROUND 25 KT WILL CONTINUE THROUGH THE
WEEKEND BEFORE FINALLY TAPERING MONDAY AS HIGH PRESSURE BUILDS IN
FROM THE WEST. DUE TO THE COLD TEMPERATURES ALOFT AND RELATIVELY
WARM LAKE MICHIGAN WATERS...LAKE EFFECT SHOWERS AND POSSIBLY EVEN
THUNDERSTORMS ARE EXPECTED TO INCREASE THIS EVENING AND SUNDAY. AT
LEAST ONE WATERSPOUT HAS ALREADY BEEN REPORTED AND MORE ARE POSSIBLE
THROUGH SUNDAY EVENING. INVERSION HEIGHTS BEGIN TO COME DOWN SUNDAY
NIGHT INTO EARLY MONDAY AND SHOULD END THE LAKE EFFECT/WATERSPOUT
CHANCES. RELATIVELY QUIET WEATHER IS EXPECTED MUCH OF NEXT WEEK AS
HIGH PRESSURE BUILDS ACROSS THE OHIO VALLEY AND GREAT LAKES. A WEAK
COLD FRONT MIDWEEK MOVE ACROSS THE LAKE MIDWEEK...BUT WINDS SHOULD
STAY RELATIVELY LIGHT.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...BEACH HAZARDS STATEMENT...INZ001 UNTIL 10 PM SUNDAY.
BEACH HAZARDS STATEMENT...INZ002 UNTIL 10 AM MONDAY.
LM...SMALL CRAFT ADVISORY...LMZ743-LMZ744 UNTIL 10 PM SUNDAY.
SMALL CRAFT ADVISORY...NEARSHORE BURNS HARBOR TO MICHIGAN CITY IN UNTIL 10 AM MONDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS LINCOLN IL
1141 PM CDT SAT JUL 27 2013
.DISCUSSION...
ISSUED 825 PM CDT SAT JUL 27 2013
MUCH OF THE DIURNAL CUMULUS HAS DISSIPATED...BUT A LARGE AREA OF
STRATOCUMULUS CONTINUES TO PIVOT SOUTHEAST AROUND THE COLD CORE
UPPER LOW IN WISCONSIN. SOUTHERN FRINGE OF THIS IS NUDGING THE FAR
NORTHERN CWA. LATEST RAP MODEL CONTINUES TO SHOW SOME OF THIS
SPREADING OVER ABOUT THE NORTHEAST THIRD OF THE CWA BEFORE
SHIFTING EASTWARD OVERNIGHT. DEW POINTS IN THE UPPER 40S TO AROUND
50 DEGREES WERE WIDESPREAD...WITH EVEN COOLER VALUES UPSTREAM...
AND THIS CONTINUES TO POINT TO RECORD OR NEAR-RECORD LOWS OVER
PRETTY MUCH ALL OF THE FORECAST AREA TONIGHT.
ONLY MADE SOME MINOR ADJUSTMENTS TO THE GRIDDED FORECASTS TO
REFLECT THE LATEST HOURLY TRENDS...BUT PREVIOUS FORECAST IS
OVERALL IN GOOD SHAPE.
GEELHART
&&
.AVIATION...
ISSUED 1140 PM CDT SAT JUL 27 2013
SCATTERED TO BROKEN CLOUDS AROUND 7000 FEET WERE TRACKING THROUGH
KPIA AND KBMI LATE SATURDAY EVENING...ASSOCIATED WITH THE LARGE
UPPER LOW SPINNING OVER WISCONSIN. RAP MODEL GUIDANCE SUGGESTS NOT
TOO MUCH FURTHER SOUTH PROGRESS THE REMAINDER OF THE NIGHT...
GENERALLY FOLLOWING WEAK DISTURBANCES ROTATING THROUGH THE FLOW.
AS SUCH...WILL LIMIT ANY CEILINGS TO THE KPIA-KCMI CORRIDOR FOR
NOW...AND JUST MENTION SCATTERED CLOUDS ELSEWHERE. GUSTY WEST
WINDS EXPECTED TO DEVELOP AGAIN LATE SUNDAY MORNING...ALONG WITH
ADDITIONAL DIURNAL CUMULUS. AS THE UPPER LOW PULLS AWAY LATE
SUNDAY...THE CLOUDS WILL FADE AGAIN TOWARD SUNSET...AND WINDS
BECOME LIGHT DUE TO A NARROW AXIS OF HIGH PRESSURE EXTENDING
NORTHWEST INTO IOWA.
GEELHART
&&
.CLIMATE...
ISSUED 820 PM CDT SAT JUL 27 2013
RECORD LOWS FOR SUNDAY MORNING...
BLOOMINGTON...49 IN 1895
CHAMPAIGN.....50 IN 1895
CHARLESTON....51 IN 1920
DECATUR.......51 IN 1994
EFFINGHAM.....51 IN 1962
LINCOLN.......50 IN 1920
OLNEY.........52 IN 1937
PARIS.........51 IN 1937
PEORIA........47 IN 1962
SPRINGFIELD...53 IN 2004
GEELHART
&&
.PREV DISCUSSION...
ISSUED 259 PM CDT SAT JUL 27 2013
UNSEASONABLY COLD AIR WILL PROVIDE RELIEF FROM TYPICAL MID-SUMMER
HEAT FOR THE REMAINDER OF THE WEEKEND. HIGH TEMPS WILL ACTUALLY
REMAIN BELOW NORMAL THROUGH MUCH OF THIS WEEK. NEXT FRIDAY HIGHS
MAY REACH UP CLOSER TO NORMAL IN THE MID 80S. THE NEXT WAVE OF
RAIN AND STORMS IS FORECAST FOR LATE MONDAY NIGHT THROUGH
TUESDAY NIGHT. THE MODELS CONTINUE TO SHOW THE MAIN FORCING FOR
PRECIP ACROSS OUR SOUTHERN COUNTIES DURING THAT TIME...WHERE 1-2"
OF RAIN MAY FALL. A LATE WEEK FRONTAL BOUNDARY MAY TRIGGER STORMS
FRIDAY INTO SATURDAY.
SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT.
A COLD CORE LOW CENTERED OVER NORTHERN WISCONSIN AND LAKE SUPERIOR
WILL CHURN DIURNAL CLOUD COVER AND A FEW SPRINKLES INTO OUR NORTHERN
COUNTIES THE REST OF THE AFTERNOON. DISSIPATION OF THE MAJORITY OF
THE CLOUDS SHOULD COME EARLY THIS EVENING. MORE PROMINENT CLOUD
COVER ACROSS EASTERN MINNESOTA AND N IOWA IS PROJECTED TO ROTATE
INTO N IL TONIGHT. WE MAY SEE THOSE CLOUDS AFFECT THE NORTHERN
TIER OF OUR COUNTIES FROM GALESBURG TO CHAMPAIGN. TIMING OF THOSE
CLOUDS WOULD HAVE AN EFFECT ON LOW TEMPS TONIGHT. IN GENERAL, BY
MORNING MOST AREAS SHOULD HAVE MINIMAL CLOUD COVER. GFS/MAV
GUIDANCE IS GOING COLDER THAN THE NAM/MET GUID FOR LOWS TONIGHT.
THE MAV HAS 47 FOR SPI, WHICH WOULD CRUSH THE PREVIOUS RECORD LOW
OF 53 BY 6 DEGREES. WE ARE NOT GOING QUITE THAT LOW...BUT HAVE
TRIMMED A COUPLE DEGREES FROM THE PREVIOUS FORECAST WITH 49.
AFTERNOON DEWPOINTS HAVE MIXED OUT DOWN INTO THE MID 40S...BUT WE
EXPECT LOWS TO BE MAINLY IN THE UPPER 40S TO LOWER 50S. AS A
RESULT, MOST AREAS WILL BE SEEING RECORD OR NEAR RECORD COLD FOR
THE MORNING OF JULY 28.
THE AIR MASS WILL NOT CHANGE APPRECIABLY FOR SUNDAY AS A
REINFORCING LOBE OF COLD AIR ROTATES SOUTH INTO NORTHERN ILLINOIS.
WE SHOULD SEE SIMILAR CONDITIONS TOMORROW AS TODAY...WITH CLOUDS
FILLING IN WITH ANY SUNSHINE. WE DID NOT ADD SPRINKLES TO THE
GRIDS FOR TOMORROW AFTERNOON AT THIS POINT...ALTHOUGH BEST CHANCES
FOR SUFFICIENT UPDRAFTS FOR PRECIP LOOK TO BE ALONG OUR FAR
NORTHEAST COUNTIES...MAYBE FROM BMI TO CMI AND DNV. HIGH TEMPS
TOMORROW WILL ONCE AGAIN STRUGGLE TO REACH THE LOWER 70S. THE
COLDEST AIR ON SUNDAY NIGHT WILL BE IN THE NORTHEAST...WHERE WE
HAVE A SMALL AREA OF UPPER 40S EAST OF CMI. THE REMAINDER OF THE
AREA SHOULD DROP INTO THE 50-55F RANGE UNDER CLEAR SKIES AND LIGHT
WINDS.
MONDAY WILL SEE SOME LOW AND MID LEVEL WARMING...AS THE UPPER
TROUGH FINALLY DEPARTS TO THE EASTERN GREAT LAKES AND WE SEE MORE
ZONAL FLOW ALOFT. 850MB TEMPS SHOULD CLIMB BACK INTO THE 12-16C
RANGE...HELPING PUSH HIGHS INTO THE UPPER 70S. THE WARMUP WILL BE
ACCOMPANIED BY CLOUDS INCREASING MONDAY AFTERNOON...WITH A FEW
SHOWERS EVEN POSSIBLE IN OUR WESTERN COUNTIES AHEAD OF THE NEXT
LOW PRESSURE SYSTEM. SHOWER/STORM CHANCES WILL INCREASE MONDAY
NIGHT AS MID LEVEL WARM ADVECTION AND WARM FRONTOGENESIS
INCREASES. WE KEPT SOME LIKELY POPS SOUTHWEST OF SPI BUT BUMPED
THEM TO AFTER MIDNIGHT...BASED ON A SLIGHTLY SLOWER CONSENSUS OF
THE ECMWF/GFS/CANADIAN.
WE ARE NOT EXPECTED SEVERE WEATHER...BUT HEAVY RAINFALL AND FLASH
FLOODING WILL BECOME POSSIBLE AS PRECIPITABLE WATER VALUES CLIMB
BETWEEN 1.5-2" MONDAY NIGHT INTO TUESDAY ACROSS CENTRAL AND SE IL.
THE WEST TO EAST ORIENTATION OF THE WARM FRONT AND THE TRACK OF
THE LOW ALONG THAT FRONT WILL SET THE STAGE FOR TRAINING STORMS
OVER THE SAME AREA.
THE PATH OF THE LOW IS STILL IN QUESTION...BUT MOST SOLUTIONS KEEP
THE LOW AT LEAST ALONG OF SOUTH OF I-72...WHICH IS WHERE WE HAVE
OUR HIGHEST POPS IN THE LIKELY CATEGORY TUESDAY. TUESDAY
NIGHT...THE STORMS SHOULD BE MAINLY SOUTHEAST OF I-70...SO WE
ADDED LIKELY IN THAT AREA. THE RAIN AND CLOUDS WILL KEEP TUESDAYS
HIGHS IN THE MID 70S...A LITTLE COOLER THAN MONDAY.
LONG TERM...WEDNESDAY THROUGH SATURDAY.
THE SLOWER TRACK OF THE LOW MAY ALLOW A FEW SHOWERS/STORMS TO
LINGER INTO WEDNESDAY...MAINLY IN THE EAST. THE CANADIAN AND GFS
WETTER SOLUTION PROMPTED SOME CHANCE POPS EAST OF LINCOLN. DRY
CONDITIONS SHOULD RETURN FOR THURSDAY AS WEAK HIGH PRESSURE
RETURNS TO ILLINOIS.
THE LATTER HALF OF THE WEEK SHOULD AT LEAST SEE HIGHS CLIMB BACK
UP AROUND 80 WITH MID 80S POSSIBLE FRIDAY...AS THE GFS INDICATES
ADDITIONAL WARMING AT 850MB WITH 22C EXTENDING FROM ST LOUIS TO
PEORIA. THE ECMWF IS COOLER WITH 18C BARELY ENTERING WESTERN IL.
WE TRENDED WARMER...BUT STILL ONLY LOW TO MID 80S FOR NOW.
STORMS ARE FORECAST TO DEVELOP AHEAD OF THE COLD FRONT ON FRIDAY
AS A LOW LEVEL JET INCREASES MID LEVEL WARM ADVECTION. STORM
CHANCES WILL CONTINUE ON SATURDAY WHEN THE COLD FRONT PASSES FROM
NW TO SE ACROSS IL.
SHIMON
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
223 PM EDT SUN JUL 28 2013
.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW
&&
.SYNOPSIS...
ISSUED AT 259 AM EDT SUN JUL 28 2013
COOL CANADIAN AIR ASSOCIATED WITH HIGH PRESSURE IS EXPECTED TO
BUILD ACROSS INDIANA AND THE OHIO VALLEY THROUGH MONDAY. THE NEXT
WIDESPREAD CHANCE FOR SHOWERS AND THUNDERSTORMS WILL BE BEGIN
MONDAY NIGHT INTO WEDNESDAY AS A WARM FRONT AND LOW PRESSURE
SYSTEM OVER THE CENTRAL PLAINS PUSHES INTO THE OHIO VALLEY. A
RETURN TO SUMMER IS EXPECTED LATE NEXT WEEK AS WARMER AIR BEGINS
TO ARRIVE FROM THE PLAINS STATES.
&&
.NEAR TERM /TODAY/...
ISSUED AT 953 AM EDT SUN JUL 28 2013
UPDATE FOCUSES ON SKY TRENDS WITH CONVECTIVE TEMPS EXPECTED TO BE
REACHED AROUND 16-17Z. WILL CONTINUE TO CONFINE SLIGHT CHANCE POPS
LATE THIS MORNING INTO AFTERNOON NORTH OF THE CAPITAL CITY IN LINE
WITH HRRR TRENDS...WHICH SEEM TO HAVE A GOOD HANDLE ON THE
SITUATION WITH STRUGGLING LIGHT SHOWERS ACROSS NORTHERN
IL/NORTHWEST INDIANA THIS MORNING. WITH SOME SKY COVER ALREADY
MOVING INTO NORTHERN FORECAST AREA...DID TRIM HIGH TEMPS BACK JUST
SLIGHTLY ACROSS THE NORTHERN TIER. PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 259 AM EDT SUN JUL 28 2013
WHILE DRY WEATHER IS GENERALLY EXPECTED FOR THE NEXT 2 DAYS...AM
CONCERNED THAT PRECIPITATION FROM AN UPPER/SURFACE LOW OVER THE
GREAT LAKES MAY REACH CENTRAL INDIANA THIS AFTERNOON AS SEVERAL
SPOKES OF ENERGY ROTATE THROUGH THIS FEATURE AS IT MOVES SLOWLY
ACROSS THE GL REGION. MODELS...MOST NOTABLY THE GFS ARE SHOWING
PRECIP REACHING AS FAR SOUTH AS THE I-70 CORRIDOR...WHILE THE NAM IS
KEEPING IT JUST NORTH OF THE CWA. WHILE FORECAST SOUNDINGS DO LOOK
TOO DRY TO ALLOW THE FAR REACHES OF THIS PRECIP TO REACH THE AREA
AND THE SURFACE...THE MODELS HAVE BEEN HINTING AT THIS FOR THE LAST
24 HRS. IF ANY SHOWERS DO MAKE IT INTO THE FORECAST AREA IT WOULD BE
OVER THE NE COUNTIES...CLOSEST TO THE LOW. CONFIDENCE IS
LOW...HOWEVER WE ARE CURRENTLY SEEING SOME LIGHT SHOWERS REACH THE
GROUND ACROSS THE SOUTHERN GREAT LAKES AT THIS HOUR...SO WOULD
PREFER NOT TO RULE ANY CHANCES OUT. HAVE THEREFORE OPTED TO INCLUDE
A SLIGHT CHANCE POP FOR SHOWERS FOR THE NE COUNTIES THIS AFTERNOON.
THIS IS NOT A DRAMATIC DEPARTURE FROM PREVIOUS FORECAST AS IT IS
ONLY SLIGHT CHANCE...BUT DEVIATES FROM THE COMPLETELY DRY FORECAST.
ATTENTION THEN TURNS TO THE SECOND CONCERN FOR THIS AFTERNOON WHICH
IS TEMPS. BELIEVE MOS IS ON THE LOW SIDE CONSIDERING THE MODERATE
W/SW FLOW FORECAST. WENT A FEW DEGREES ABOVE FOR HIGHS RANGING 72
TO 78.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
ISSUED AT 259 AM EDT SUN JUL 28 2013
MAIN CHANGE THIS PERIOD WAS TO REINTRODUCE POPS ACROSS THE WRN
COUNTIES BEGINNING MONDAY NIGHT BASED ON GOOD MODEL CONSENSUS.
COOLER TEMPERATURES WILL CONTINUE THROUGH THIS PERIOD WITH HIGHS
BELOW THE 80 MARK AND LOWS IN THE 50S TONIGHT...THEN 60S THE NEXT
TWO NIGHTS. KIND DOES NOT LOOK TO BREAK ANY LOWS OR RECORD LOW
MAXIMUMS.
MODELS SHOW A WARM FRONT AND LOW PRESSURE SYSTEM APPROACHING CENTRAL
INDIANA FROM THE CENTRAL PLAINS ON MONDAY NIGHT INTO TUESDAY. BEST
MOISTURE LOOKS TO ARRIVE ON TUESDAY...HOWEVER AS MENTIONED ABOVE
GUIDANCE SUGGESTS THE COLUMN ACROSS THE WRN COUNTIES WILL BE MOIST
ENOUGH TO POSSIBLE ALLOW POPS HERE BY MONDAY NIGHT. CHANCES FOR
SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH THE REST OF THE
PERIOD.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
ISSUED AT 224 PM EDT SUN JUL 28 2013
HAVE CONTINUED POPS ON WEDNESDAY NIGHT AS GFS SUGGESTS A COLD
FRONT STILL PUSHING THROUGH THE AREA. NORTHWEST FLOW ALONG WITH
HIGH PRESSURE IN PLACE AT THE SURFACE IS EXPECTED TO PERSIST
THROUGH FRIDAY NIGHT...PROVIDING DRY WEATHER. GIVEN THE NORTHWEST
FLOW ALOFT...AND THE LIMITED DEVELOPMENT OF WARM AIR
ARRIVING...HAVE TRENDED HIGHS AND LOWS AT OR BELOW ALL BLEND VALUES.
THE GFS CONTINUES TO DEPICT HIGH PRESSURE IN PLACE ACROSS THE
OHIO VALLEY ON FRIDAY NIGHT THROUGH SUNDAY...HOWEVER IT DOES
SUGGEST A WARM FRONT APPROACHING THE AREA FROM THE SOUTHWEST AS
THE MAIN JET FLOW ALOFT IS FROM THE NW...SPILLING WEAK SHORT WAVES
INTO THE OHIO VALLEY. CONFIDENCE IN THESE FEATURES IS LOW AND A
DRY FORECAST WOULD BE PREFERRED...HOWEVER ALL BLEND WISHES TO KEEP
POPS DUE TO THE BOUNDARY STILL BEING IN PLACE. WILL LEAVE POPS IN
FOR NOW.
&&
.AVIATION /DISCUSSION FOR THE 281800Z TAFS/...
ISSUED AT 1231 PM EDT SUN JUL 28 2013
MAINLY VFR CONDITIONS WILL BE EXPECTED THIS TAF PERIOD.
DIURNAL BKN CU WILL DISSIPATE LATE THIS AFTERNOON AND EVENING AS
HEATING IS LOST...LEADING TO UNLIMITED CEILINGS OVERNIGHT. HIGH
PRESSURE OVER THE CENTRAL PLAINS IS EXPECTED TO BUILD ACROSS THE
OHIO VALLEY OVERNIGHT...LEADING TO LIGHT WINDS AND CLEAR SKIES.
THIS WILL RESULT IN IDEAL RADIATIONAL COOLING CONDITIONS. THUS
HAVE INCLUDED SOME MVFR VISIBILITIES OVERNIGHT AS DEW POINT
DEPRESSIONS LOOK TO BE 2F OR LESS.
ANY MORNING FOG WILL QUICKLY BURN OFF AFTER SUNRISE ON MONDAY AS
DAYTIME HEATING RESUMES.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF/NIELD
SHORT TERM...SMF
LONG TERM....PUMA
AVIATION...JP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1242 PM EDT SUN JUL 28 2013
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW
&&
.SYNOPSIS...
ISSUED AT 259 AM EDT SUN JUL 28 2013
COOL CANADIAN AIR ASSOCIATED WITH HIGH PRESSURE IS EXPECTED TO
BUILD ACROSS INDIANA AND THE OHIO VALLEY THROUGH MONDAY. THE NEXT
WIDESPREAD CHANCE FOR SHOWERS AND THUNDERSTORMS WILL BE BEGIN
MONDAY NIGHT INTO WEDNESDAY AS A WARM FRONT AND LOW PRESSURE
SYSTEM OVER THE CENTRAL PLAINS PUSHES INTO THE OHIO VALLEY. A
RETURN TO SUMMER IS EXPECTED LATE NEXT WEEK AS WARMER AIR BEGINS
TO ARRIVE FROM THE PLAINS STATES.
&&
.NEAR TERM /TODAY/...
ISSUED AT 953 AM EDT SUN JUL 28 2013
UPDATE FOCUSES ON SKY TRENDS WITH CONVECTIVE TEMPS EXPECTED TO BE
REACHED AROUND 16-17Z. WILL CONTINUE TO CONFINE SLIGHT CHANCE POPS
LATE THIS MORNING INTO AFTERNOON NORTH OF THE CAPITAL CITY IN LINE
WITH HRRR TRENDS...WHICH SEEM TO HAVE A GOOD HANDLE ON THE
SITUATION WITH STRUGGLING LIGHT SHOWERS ACROSS NORTHERN
IL/NORTHWEST INDIANA THIS MORNING. WITH SOME SKY COVER ALREADY
MOVING INTO NORTHERN FORECAST AREA...DID TRIM HIGH TEMPS BACK JUST
SLIGHTLY ACROSS THE NORTHERN TIER. PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 259 AM EDT SUN JUL 28 2013
WHILE DRY WEATHER IS GENERALLY EXPECTED FOR THE NEXT 2 DAYS...AM
CONCERNED THAT PRECIPITATION FROM AN UPPER/SURFACE LOW OVER THE
GREAT LAKES MAY REACH CENTRAL INDIANA THIS AFTERNOON AS SEVERAL
SPOKES OF ENERGY ROTATE THROUGH THIS FEATURE AS IT MOVES SLOWLY
ACROSS THE GL REGION. MODELS...MOST NOTABLY THE GFS ARE SHOWING
PRECIP REACHING AS FAR SOUTH AS THE I-70 CORRIDOR...WHILE THE NAM IS
KEEPING IT JUST NORTH OF THE CWA. WHILE FORECAST SOUNDINGS DO LOOK
TOO DRY TO ALLOW THE FAR REACHES OF THIS PRECIP TO REACH THE AREA
AND THE SURFACE...THE MODELS HAVE BEEN HINTING AT THIS FOR THE LAST
24 HRS. IF ANY SHOWERS DO MAKE IT INTO THE FORECAST AREA IT WOULD BE
OVER THE NE COUNTIES...CLOSEST TO THE LOW. CONFIDENCE IS
LOW...HOWEVER WE ARE CURRENTLY SEEING SOME LIGHT SHOWERS REACH THE
GROUND ACROSS THE SOUTHERN GREAT LAKES AT THIS HOUR...SO WOULD
PREFER NOT TO RULE ANY CHANCES OUT. HAVE THEREFORE OPTED TO INCLUDE
A SLIGHT CHANCE POP FOR SHOWERS FOR THE NE COUNTIES THIS AFTERNOON.
THIS IS NOT A DRAMATIC DEPARTURE FROM PREVIOUS FORECAST AS IT IS
ONLY SLIGHT CHANCE...BUT DEVIATES FROM THE COMPLETELY DRY FORECAST.
ATTENTION THEN TURNS TO THE SECOND CONCERN FOR THIS AFTERNOON WHICH
IS TEMPS. BELIEVE MOS IS ON THE LOW SIDE CONSIDERING THE MODERATE
W/SW FLOW FORECAST. WENT A FEW DEGREES ABOVE FOR HIGHS RANGING 72
TO 78.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
ISSUED AT 259 AM EDT SUN JUL 28 2013
MAIN CHANGE THIS PERIOD WAS TO REINTRODUCE POPS ACROSS THE WRN
COUNTIES BEGINNING MONDAY NIGHT BASED ON GOOD MODEL CONSENSUS.
COOLER TEMPERATURES WILL CONTINUE THROUGH THIS PERIOD WITH HIGHS
BELOW THE 80 MARK AND LOWS IN THE 50S TONIGHT...THEN 60S THE NEXT
TWO NIGHTS. KIND DOES NOT LOOK TO BREAK ANY LOWS OR RECORD LOW
MAXIMUMS.
MODELS SHOW A WARM FRONT AND LOW PRESSURE SYSTEM APPROACHING CENTRAL
INDIANA FROM THE CENTRAL PLAINS ON MONDAY NIGHT INTO TUESDAY. BEST
MOISTURE LOOKS TO ARRIVE ON TUESDAY...HOWEVER AS MENTIONED ABOVE
GUIDANCE SUGGESTS THE COLUMN ACROSS THE WRN COUNTIES WILL BE MOIST
ENOUGH TO POSSIBLE ALLOW POPS HERE BY MONDAY NIGHT. CHANCES FOR
SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH THE REST OF THE
PERIOD.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ISSUED AT 259 AM EDT SUN JUL 28 2013
A LOW PRESSURE SYSTEM WILL BE MOVING THROUGH ON WEDNESDAY AND
PERHAPS INTO WEDNESDAY NIGHT BRINGING THUNDERSTORM CHANCES TO THE
AREA. GFS AND ECMWF STILL CANNOT AGREE ON THE LOCATION/TIMING OF
THIS SYSTEM SO THOUGHT ALLBLEND BROADBRUSH OF CHANCE POPS FOR
WEDNESDAY AND HOLDING ONTO A SLIGHT CHANCE WEDNESDAY NIGHT WAS A
GOOD REPRESENTATION OF THE UNCERTAINTY. HIGH PRESSURE BUILDS IN ON
THURSDAY AND DRIES OUT THE COLUMN KEEPING DRY WEATHER IN THE
FORECAST THROUGH FRIDAY. BY FRIDAY NIGHT A LOW PRESSURE SYSTEM
ACROSS THE PLAINS MOVES NORTHEAST TOWARD THE AREA AND THEN DRAGS A
COLD FRONT THROUGH DURING THE WEEKEND WITH THE GFS FAVORING SATURDAY
AND THE ECMWF SATURDAY NIGHT. HIGH TEMPERATURES WILL GENERALLY RUN A
COUPLE DEGREES COOLER THAN NORMAL UNDER NORTHWEST UPPER FLOW AND
ALLBLEND CAPTURED THIS WELL.
&&
.AVIATION /DISCUSSION FOR THE 281800Z TAFS/...
ISSUED AT 1231 PM EDT SUN JUL 28 2013
MAINLY VFR CONDITIONS WILL BE EXPECTED THIS TAF PERIOD.
DIURNAL BKN CU WILL DISSIPATE LATE THIS AFTERNOON AND EVENING AS
HEATING IS LOST...LEADING TO UNLIMITED CEILINGS OVERNIGHT. HIGH
PRESSURE OVER THE CENTRAL PLAINS IS EXPECTED TO BUILD ACROSS THE
OHIO VALLEY OVERNIGHT...LEADING TO LIGHT WINDS AND CLEAR SKIES.
THIS WILL RESULT IN IDEAL RADIATIONAL COOLING CONDITIONS. THUS
HAVE INCLUDED SOME MVFR VISIBILITIES OVERNIGHT AS DEW POINT
DEPRESSIONS LOOK TO BE 2F OR LESS.
ANY MORNING FOG WILL QUICKLY BURN OFF AFTER SUNRISE ON MONDAY AS
DAYTIME HEATING RESUMES.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF/NIELD
SHORT TERM...SMF
LONG TERM....CP
AVIATION...JP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
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WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1021 AM EDT SUN JUL 28 2013
.UPDATE...
AVIATION SECTIONS UPDATED
&&
.SYNOPSIS...
ISSUED AT 259 AM EDT SUN JUL 28 2013
COOL CANADIAN AIR ASSOCIATED WITH HIGH PRESSURE IS EXPECTED TO
BUILD ACROSS INDIANA AND THE OHIO VALLEY THROUGH MONDAY. THE NEXT
WIDESPREAD CHANCE FOR SHOWERS AND THUNDERSTORMS WILL BE BEGIN
MONDAY NIGHT INTO WEDNESDAY AS A WARM FRONT AND LOW PRESSURE
SYSTEM OVER THE CENTRAL PLAINS PUSHES INTO THE OHIO VALLEY. A
RETURN TO SUMMER IS EXPECTED LATE NEXT WEEK AS WARMER AIR BEGINS
TO ARRIVE FROM THE PLAINS STATES.
&&
.NEAR TERM /TODAY/...
ISSUED AT 953 AM EDT SUN JUL 28 2013
UPDATE FOCUSES ON SKY TRENDS WITH CONVECTIVE TEMPS EXPECTED TO BE
REACHED AROUND 16-17Z. WILL CONTINUE TO CONFINE SLIGHT CHANCE POPS
LATE THIS MORNING INTO AFTERNOON NORTH OF THE CAPITAL CITY IN LINE
WITH HRRR TRENDS...WHICH SEEM TO HAVE A GOOD HANDLE ON THE
SITUATION WITH STRUGGLING LIGHT SHOWERS ACROSS NORTHERN
IL/NORTHWEST INDIANA THIS MORNING. WITH SOME SKY COVER ALREADY
MOVING INTO NORTHERN FORECAST AREA...DID TRIM HIGH TEMPS BACK JUST
SLIGHTLY ACROSS THE NORTHERN TIER. PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 259 AM EDT SUN JUL 28 2013
WHILE DRY WEATHER IS GENERALLY EXPECTED FOR THE NEXT 2 DAYS...AM
CONCERNED THAT PRECIPITATION FROM AN UPPER/SURFACE LOW OVER THE
GREAT LAKES MAY REACH CENTRAL INDIANA THIS AFTERNOON AS SEVERAL
SPOKES OF ENERGY ROTATE THROUGH THIS FEATURE AS IT MOVES SLOWLY
ACROSS THE GL REGION. MODELS...MOST NOTABLY THE GFS ARE SHOWING
PRECIP REACHING AS FAR SOUTH AS THE I-70 CORRIDOR...WHILE THE NAM IS
KEEPING IT JUST NORTH OF THE CWA. WHILE FORECAST SOUNDINGS DO LOOK
TOO DRY TO ALLOW THE FAR REACHES OF THIS PRECIP TO REACH THE AREA
AND THE SURFACE...THE MODELS HAVE BEEN HINTING AT THIS FOR THE LAST
24 HRS. IF ANY SHOWERS DO MAKE IT INTO THE FORECAST AREA IT WOULD BE
OVER THE NE COUNTIES...CLOSEST TO THE LOW. CONFIDENCE IS
LOW...HOWEVER WE ARE CURRENTLY SEEING SOME LIGHT SHOWERS REACH THE
GROUND ACROSS THE SOUTHERN GREAT LAKES AT THIS HOUR...SO WOULD
PREFER NOT TO RULE ANY CHANCES OUT. HAVE THEREFORE OPTED TO INCLUDE
A SLIGHT CHANCE POP FOR SHOWERS FOR THE NE COUNTIES THIS AFTERNOON.
THIS IS NOT A DRAMATIC DEPARTURE FROM PREVIOUS FORECAST AS IT IS
ONLY SLIGHT CHANCE...BUT DEVIATES FROM THE COMPLETELY DRY FORECAST.
ATTENTION THEN TURNS TO THE SECOND CONCERN FOR THIS AFTERNOON WHICH
IS TEMPS. BELIEVE MOS IS ON THE LOW SIDE CONSIDERING THE MODERATE
W/SW FLOW FORECAST. WENT A FEW DEGREES ABOVE FOR HIGHS RANGING 72
TO 78.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
ISSUED AT 259 AM EDT SUN JUL 28 2013
MAIN CHANGE THIS PERIOD WAS TO REINTRODUCE POPS ACROSS THE WRN
COUNTIES BEGINNING MONDAY NIGHT BASED ON GOOD MODEL CONSENSUS.
COOLER TEMPERATURES WILL CONTINUE THROUGH THIS PERIOD WITH HIGHS
BELOW THE 80 MARK AND LOWS IN THE 50S TONIGHT...THEN 60S THE NEXT
TWO NIGHTS. KIND DOES NOT LOOK TO BREAK ANY LOWS OR RECORD LOW
MAXIMUMS.
MODELS SHOW A WARM FRONT AND LOW PRESSURE SYSTEM APPROACHING CENTRAL
INDIANA FROM THE CENTRAL PLAINS ON MONDAY NIGHT INTO TUESDAY. BEST
MOISTURE LOOKS TO ARRIVE ON TUESDAY...HOWEVER AS MENTIONED ABOVE
GUIDANCE SUGGESTS THE COLUMN ACROSS THE WRN COUNTIES WILL BE MOIST
ENOUGH TO POSSIBLE ALLOW POPS HERE BY MONDAY NIGHT. CHANCES FOR
SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH THE REST OF THE
PERIOD.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ISSUED AT 259 AM EDT SUN JUL 28 2013
A LOW PRESSURE SYSTEM WILL BE MOVING THROUGH ON WEDNESDAY AND
PERHAPS INTO WEDNESDAY NIGHT BRINGING THUNDERSTORM CHANCES TO THE
AREA. GFS AND ECMWF STILL CANNOT AGREE ON THE LOCATION/TIMING OF
THIS SYSTEM SO THOUGHT ALLBLEND BROADBRUSH OF CHANCE POPS FOR
WEDNESDAY AND HOLDING ONTO A SLIGHT CHANCE WEDNESDAY NIGHT WAS A
GOOD REPRESENTATION OF THE UNCERTAINTY. HIGH PRESSURE BUILDS IN ON
THURSDAY AND DRIES OUT THE COLUMN KEEPING DRY WEATHER IN THE
FORECAST THROUGH FRIDAY. BY FRIDAY NIGHT A LOW PRESSURE SYSTEM
ACROSS THE PLAINS MOVES NORTHEAST TOWARD THE AREA AND THEN DRAGS A
COLD FRONT THROUGH DURING THE WEEKEND WITH THE GFS FAVORING SATURDAY
AND THE ECMWF SATURDAY NIGHT. HIGH TEMPERATURES WILL GENERALLY RUN A
COUPLE DEGREES COOLER THAN NORMAL UNDER NORTHWEST UPPER FLOW AND
ALLBLEND CAPTURED THIS WELL.
&&
.AVIATION /DISCUSSION FOR THE 281500Z IND TAF UPDATE/...
VFR WILL CONTINUE.
ONGOING FORECAST IN GOOD SHAPE. UPSTREAM 12Z SOUNDINGS SHOW
CONVECTIVE TEMPS IN THE UPPER 60S WITH DRY AIR ALOFT. ALONG WITH
AN INVERSION IN THE MID LEVELS THAT SHOULD CAP ANY CU DEVELOPMENT.
WITH CU RULE VALUES SIMILAR TO YESTERDAY...EXPECT SCT-BKN CU THIS
AFTERNOON AS MAX HEATING IS REACHED. CIGS SHOULD REMAIN VFR.
PREVIOUS DISCUSSION BELOW
/DISCUSSION FOR 281200Z TAF ISSUANCE/...
ISSUED AT 626 AM EDT SUN JUL 28 2013
SITES SHOULD BE VFR THROUGH THE DAY. AN UPPER WAVE MOVING THROUGH
THE GREAT LAKES WILL INCREASE CLOUD COVER THIS MORNING BUT EXPECT
CEILINGS TO BE AROUND 4-5KFT. THIS COULD ALSO PROMPT SOME LIGHT
SHOWERS AT KLAF FOR A FEW HOURS THIS MORNING BUT DON/T EXPECT TO
SEE AN IMPACT ON FLYING CONDITIONS. AT THIS TIME THINK ANY SHOWER
ACTIVITY WILL STAY NORTH OF THE REST OF THE SITES. FORECAST
SOUNDINGS AGAIN SHOW POTENTIAL FOR SOME WIND GUSTS AROUND 18-20 KTS
THIS AFTERNOON. TIME HEIGHTS SHOW A DECENT AMOUNT OF LOW LEVEL
MOISTURE OVERNIGHT WITH WEAK SUBSIDENCE SO THINK THIS COULD LEAD
TO LOWER VISIBILITIES. FOR NOW WILL INTRODUCE MVFR LATE IN THE
PERIOD.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF/NIELD
SHORT TERM...SMF
LONG TERM....CP
AVIATION...CP/JP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
953 AM EDT SUN JUL 28 2013
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 259 AM EDT SUN JUL 28 2013
COOL CANADIAN AIR ASSOCIATED WITH HIGH PRESSURE IS EXPECTED TO
BUILD ACROSS INDIANA AND THE OHIO VALLEY THROUGH MONDAY. THE NEXT
WIDESPREAD CHANCE FOR SHOWERS AND THUNDERSTORMS WILL BE BEGIN
MONDAY NIGHT INTO WEDNESDAY AS A WARM FRONT AND LOW PRESSURE
SYSTEM OVER THE CENTRAL PLAINS PUSHES INTO THE OHIO VALLEY. A
RETURN TO SUMMER IS EXPECTED LATE NEXT WEEK AS WARMER AIR BEGINS
TO ARRIVE FROM THE PLAINS STATES.
&&
.NEAR TERM /TODAY/...
ISSUED AT 953 AM EDT SUN JUL 28 2013
UPDATE FOCUSES ON SKY TRENDS WITH CONVECTIVE TEMPS EXPECTED TO BE
REACHED AROUND 16-17Z. WILL CONTINUE TO CONFINE SLIGHT CHANCE POPS
LATE THIS MORNING INTO AFTERNOON NORTH OF THE CAPITAL CITY IN LINE
WITH HRRR TRENDS...WHICH SEEM TO HAVE A GOOD HANDLE ON THE
SITUATION WITH STRUGGLING LIGHT SHOWERS ACROSS NORTHERN
IL/NORTHWEST INDIANA THIS MORNING. WITH SOME SKY COVER ALREADY
MOVING INTO NORTHERN FORECAST AREA...DID TRIM HIGH TEMPS BACK JUST
SLIGHTLY ACROSS THE NORTHERN TIER. PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 259 AM EDT SUN JUL 28 2013
WHILE DRY WEATHER IS GENERALLY EXPECTED FOR THE NEXT 2 DAYS...AM
CONCERNED THAT PRECIPITATION FROM AN UPPER/SURFACE LOW OVER THE
GREAT LAKES MAY REACH CENTRAL INDIANA THIS AFTERNOON AS SEVERAL
SPOKES OF ENERGY ROTATE THROUGH THIS FEATURE AS IT MOVES SLOWLY
ACROSS THE GL REGION. MODELS...MOST NOTABLY THE GFS ARE SHOWING
PRECIP REACHING AS FAR SOUTH AS THE I-70 CORRIDOR...WHILE THE NAM IS
KEEPING IT JUST NORTH OF THE CWA. WHILE FORECAST SOUNDINGS DO LOOK
TOO DRY TO ALLOW THE FAR REACHES OF THIS PRECIP TO REACH THE AREA
AND THE SURFACE...THE MODELS HAVE BEEN HINTING AT THIS FOR THE LAST
24 HRS. IF ANY SHOWERS DO MAKE IT INTO THE FORECAST AREA IT WOULD BE
OVER THE NE COUNTIES...CLOSEST TO THE LOW. CONFIDENCE IS
LOW...HOWEVER WE ARE CURRENTLY SEEING SOME LIGHT SHOWERS REACH THE
GROUND ACROSS THE SOUTHERN GREAT LAKES AT THIS HOUR...SO WOULD
PREFER NOT TO RULE ANY CHANCES OUT. HAVE THEREFORE OPTED TO INCLUDE
A SLIGHT CHANCE POP FOR SHOWERS FOR THE NE COUNTIES THIS AFTERNOON.
THIS IS NOT A DRAMATIC DEPARTURE FROM PREVIOUS FORECAST AS IT IS
ONLY SLIGHT CHANCE...BUT DEVIATES FROM THE COMPLETELY DRY FORECAST.
ATTENTION THEN TURNS TO THE SECOND CONCERN FOR THIS AFTERNOON WHICH
IS TEMPS. BELIEVE MOS IS ON THE LOW SIDE CONSIDERING THE MODERATE
W/SW FLOW FORECAST. WENT A FEW DEGREES ABOVE FOR HIGHS RANGING 72
TO 78.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
ISSUED AT 259 AM EDT SUN JUL 28 2013
MAIN CHANGE THIS PERIOD WAS TO REINTRODUCE POPS ACROSS THE WRN
COUNTIES BEGINNING MONDAY NIGHT BASED ON GOOD MODEL CONSENSUS.
COOLER TEMPERATURES WILL CONTINUE THROUGH THIS PERIOD WITH HIGHS
BELOW THE 80 MARK AND LOWS IN THE 50S TONIGHT...THEN 60S THE NEXT
TWO NIGHTS. KIND DOES NOT LOOK TO BREAK ANY LOWS OR RECORD LOW
MAXIMUMS.
MODELS SHOW A WARM FRONT AND LOW PRESSURE SYSTEM APPROACHING CENTRAL
INDIANA FROM THE CENTRAL PLAINS ON MONDAY NIGHT INTO TUESDAY. BEST
MOISTURE LOOKS TO ARRIVE ON TUESDAY...HOWEVER AS MENTIONED ABOVE
GUIDANCE SUGGESTS THE COLUMN ACROSS THE WRN COUNTIES WILL BE MOIST
ENOUGH TO POSSIBLE ALLOW POPS HERE BY MONDAY NIGHT. CHANCES FOR
SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH THE REST OF THE
PERIOD.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ISSUED AT 259 AM EDT SUN JUL 28 2013
A LOW PRESSURE SYSTEM WILL BE MOVING THROUGH ON WEDNESDAY AND
PERHAPS INTO WEDNESDAY NIGHT BRINGING THUNDERSTORM CHANCES TO THE
AREA. GFS AND ECMWF STILL CANNOT AGREE ON THE LOCATION/TIMING OF
THIS SYSTEM SO THOUGHT ALLBLEND BROADBRUSH OF CHANCE POPS FOR
WEDNESDAY AND HOLDING ONTO A SLIGHT CHANCE WEDNESDAY NIGHT WAS A
GOOD REPRESENTATION OF THE UNCERTAINTY. HIGH PRESSURE BUILDS IN ON
THURSDAY AND DRIES OUT THE COLUMN KEEPING DRY WEATHER IN THE
FORECAST THROUGH FRIDAY. BY FRIDAY NIGHT A LOW PRESSURE SYSTEM
ACROSS THE PLAINS MOVES NORTHEAST TOWARD THE AREA AND THEN DRAGS A
COLD FRONT THROUGH DURING THE WEEKEND WITH THE GFS FAVORING SATURDAY
AND THE ECMWF SATURDAY NIGHT. HIGH TEMPERATURES WILL GENERALLY RUN A
COUPLE DEGREES COOLER THAN NORMAL UNDER NORTHWEST UPPER FLOW AND
ALLBLEND CAPTURED THIS WELL.
&&
.AVIATION /DISCUSSION FOR 281200Z TAF ISSUANCE/...
ISSUED AT 626 AM EDT SUN JUL 28 2013
SITES SHOULD BE VFR THROUGH THE DAY. AN UPPER WAVE MOVING THROUGH
THE GREAT LAKES WILL INCREASE CLOUD COVER THIS MORNING BUT EXPECT
CEILINGS TO BE AROUND 4-5KFT. THIS COULD ALSO PROMPT SOME LIGHT
SHOWERS AT KLAF FOR A FEW HOURS THIS MORNING BUT DON/T EXPECT TO
SEE AN IMPACT ON FLYING CONDITIONS. AT THIS TIME THINK ANY SHOWER
ACTIVITY WILL STAY NORTH OF THE REST OF THE SITES. FORECAST
SOUNDINGS AGAIN SHOW POTENTIAL FOR SOME WIND GUSTS AROUND 18-20 KTS
THIS AFTERNOON. TIME HEIGHTS SHOW A DECENT AMOUNT OF LOW LEVEL
MOISTURE OVERNIGHT WITH WEAK SUBSIDENCE SO THINK THIS COULD LEAD
TO LOWER VISIBILITIES. FOR NOW WILL INTRODUCE MVFR LATE IN THE
PERIOD.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF/NIELD
SHORT TERM...SMF
LONG TERM....CP
AVIATION...CP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
225 AM MDT SUN JUL 28 2013
.UPDATE...
ISSUED AT 954 PM MDT SAT JUL 27 2013
JUST ISSUED ANOTHER UPDATE. INITIAL CHANGE WAS TO CANCEL THE
SEVERE THUNDERSTORM WATCH. DESPITE THAT...SHOWER/THUNDERSTORM
COVERAGE IS INCREASING OVER AND TO THE WEST OF THE FORECAST AREA.
COVERAGE OVER THE CWA IS ALONG PERSISTENT BOUNDARY. THESE STORMS
HAVE SHOWN A TENDENCY TO DEVELOP TOWARD THE WEST. COVERAGE TO THE
WEST INCREASING DUE TO INCOMING SHORTWAVE TROUGH AND RIGHT REAR
QUADRANT OF THE JET STAYING OVER THE AREA WELL INTO THE OVERNIGHT
HOURS.
ALSO PER EARLIER DISCUSSION...ELEVATED INHIBITION DECREASING AS
ELEVATED CAPE INCREASE THROUGH THE NIGHT. RUC CATCHING THE ABOVE
SCENARIO NICELY...WHICH PUTS A NICE SWATH OF PRECIPITATION DOWN
THE CENTER OF THE FORECAST AREA. PER THAT AND ABOVE MENTIONED
DATA/TRENDS...FELT GOOD IN INCREASING POPS TO LIKELY IN THE ABOVE
MENTIONED AREA THROUGH THE REST OF THE NIGHT. ALSO INCREASED SKY
COVER AGAIN. EVERYTHING ELSE LOOKS GOOD FOR NOW.
UPDATE ISSUED AT 817 PM MDT SAT JUL 27 2013
MESSY WEATHER/FORECAST SITUATION. ELEVATED BOUNDARY HAS KEPT
THUNDERSTORMS GOING OVER THE FAR EAST SINCE LATE THIS AFTERNOON.
RADAR HAS SHOWN TRENDS OF THIS DEVELOPING FURTHER WEST ALONG THIS
BOUNDARY. RUC HAS CAUGHT ONTO THIS. NEW DEVELOPMENT HAS OCCURRED
TO THE WEST IN ADVANCE OF A SHORTWAVE TROUGH. PLUS RIGHT REAR
QUADRANT STAYS NEAR OVER THE AREA THROUGH THE NIGHT. ALSO THE
ELEVATED CINH DECREASES TO NEXT TO NOTHING BY THE END OF THE NIGHT
WITH ELEVATED CAPE CONTINUING.
SO LIFT...INSTABILITY AND MOISTURE INCREASE THROUGH THE NIGHT. SO
INCREASED POPS TO TAKE THIS INTO ACCOUNT BUT MAY NOT HAVE GONE FAR
ENOUGH AND KEPT THE PREVAILING WEATHER AS THUNDERSTORMS. ALSO
UPPED QPF THROUGH THE NIGHT AS WELL. ALSO ADJUSTED WINDS PER
LATEST OBSERVATIONAL TRENDS AND MODEL DATA. ALSO INCREASED CLOUD
COVER AS WELL. LOOKING AT TOMORROW...THERE IS A LOT OF CLOUD COVER
ALONG WITH EASTERLY WINDS. CURRENT MODEL GUIDANCE IN DECENT
AGREEMENT WITH SOME PLACES NOT GETTING OUT OF THE 60S. SO ADJUSTED
TEMPERATURES DOWN A FEW DEGREES AND THAT MAY NOT BE ENOUGH.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 1235 PM MDT SAT JUL 27 2013
ISOLATED SHOWERS AND THUNDERSTORMS WILL CONTINUE TO STREAM ALONG
THE NORTHWEST FLOW ALOFT ACROSS THE NORTHEAST PORTION OF THE
FORECAST AREA THIS AFTERNOON. THUNDERSTORMS WILL BECOME MORE
NUMEROUS AND SCATTERED IN NATURE ACROSS THE FORECAST AREA AS THEY
BUILD OVER THE FRONT RANGE AND MOVE INTO THE AREA THIS LATE THIS
AFTERNOON AND EVENING. SOME STORMS ACROSS THE WESTERN PORTION OF
THE FORECAST AREA MAY BECOME SEVERE WITH DAMAGING WINDS AND LARGE
HAIL POSSIBLE. THUNDERSTORMS ARE EXPECTED TO CONTINUE THROUGH THE
LATE EVENING INTO THE OVERNIGHT HOURS WITH THE FOCUS REMAINING
IN THE VICINITY OF THE FRONTAL BOUNDARY AS THE SURFACE LOW
REMAINS IN THE SOUTHEAST COLORADO/PANHANDLE REGION IN RESPONSE TO
THE SHORT WAVE TROUGH THAT CUTS THROUGH THE CENTRAL ROCKIES ACROSS
THE UPPER RIDGE AND EMERGES OVER CENTRAL HIGH PLAINS SUNDAY
MORNING. MAIN AREA OF PRECIPITATION SHOULD SHIFT EAST OVERNIGHT
FROM EASTERN COLORADO TO CENTRAL KANSAS BY MID DAY ON SUNDAY.
HYDRO ISSUES MAY BECOME A CONCERN ACROSS THE SOUTHEASTERN SECTIONS
OF THE FORECAST AREA BY LATE SUNDAY IF MULTIPLE THUNDERSTORMS
CONTINUE TO MOVE ACROSS THE SAME AREA.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 221 AM MDT SUN JUL 28 2013
UPPER LEVEL RIDGE WILL BUILD INTO THE HIGH PLAINS WEDNESDAY AS 500
MB HIGH PRESSURE SETS UP OVER THE DESERT SOUTHWEST REGION. NUMEROUS
SHORTWAVE TROUGHS WILL MOVE THROUGH THE TRI STATE AREA FOR WEDNESDAY
AND THURSDAY. UPPER LEVEL LONGWAVE TROUGH WILL MOVE INTO THE PACIFIC
NORTHWEST...BRINGING THE MAIN FLOW ALOFT TO A ZONAL PATTERN FOR
FRIDAY. SHORTWAVE TROUGH PATTERNS WILL STILL EXIST FRIDAY AND INTO
SATURDAY FOR THE AREA. 850 MB WINDS WEDNESDAY AND THURSDAY WILL BE
FROM THE SOUTH AND ADVECTING WARMER TEMPERATURES TO THE REGION. A
LOW PRESSURE SYSTEM WILL MOVE THROUGH THE AREA FRIDAY
AFTERNOON...BRINGING COOLER AIR INTO THE HIGH PLAINS FOR NEXT
WEEKEND. THETA E VALUES AHEAD OF THE FRONTAL SYSTEM LOOK TO BE
AROUND 350 K...INDICATING THAT LOWER LEVEL MOISTURE COULD BE
AVAILABLE FOR RAIN SHOWERS AT THE SURFACE. HOWEVER...PRECIPITABLE
WATER AMOUNTS FROM SOUNDING FORECASTS INDICATE SOMEWHAT LOW MOISTURE
AMOUNTS THROUGHOUT THE PROFILES FOR THE AREA THROUGH THE PERIOD.
MODERATE INSTABILITY WILL BE PRESENT OVER THE AREA THROUGHOUT THE
EXTENDED PERIOD TO ALLOW FOR THUNDERSTORM DEVELOPMENT TO OCCUR FOR
EACH DAY. SURFACE DEWPOINTS ARE EXPECTED TO BE IN THE UPPER 50S TO
LOWER 60S THROUGHOUT THE PERIOD.
A WEAK SURFACE HIGH PRESSURE WILL MOVE TO THE EAST OF THE TRI STATE
AREA ON WEDNESDAY AND THURSDAY...GIVING AWAY TO A LOW PRESSURE
SYSTEM THAT WILL SLIDE DOWN THE HIGH PLAINS FROM THE NORTH. SURFACE
FRONT IS EXPECTED TO MOVE THROUGH THE AREA EARLY FRIDAY AFTERNOON AS
COOLER AIR FILTERS INTO THE REGION FOR SATURDAY...WHICH WILL KEEP
HIGH TEMPERATURES IN THE LOWER 80S FOR SATURDAY. MODEL SOUNDINGS
INDICATE DRY SLOT OF AIR WILL MOVE INTO THE HIGH PLAINS THURSDAY
EVENING BEFORE FRONTAL PASSAGE EARLY FRIDAY AFTERNOON...SO MINIMAL
PRECIPITATION IS EXPECTED WITH LOW POPS FOR FRIDAY.
HIGH TEMPERATURES ACROSS THE REGION WILL BE AROUND NORMAL...WITH
VALUES IN THE HIGH 80S TO LOWER 90S. TEMPERATURES WILL DROP TO THE
LOWER 80S FOR SATURDAY WITH COLD AIR FILTERING INTO THE AREA BEHIND THE
FRONTAL PASSAGE ON FRIDAY. BEST CHANCE FOR PRECIPITATION WILL BE FOR
SATURDAY ACROSS THE AREA AS COLDER AIR WILL CONDENSE THE MOISTURE
ACROSS THE AREA. STABLE AIR ALOFT WITH LOW CAPE AMOUNTS INDICATE
PRECIPITATION WILL LIKELY BE STRATIFORM RATHER THAN CONVECTIVE
SATURDAY...SO SEVERE WEATHER IS UNLIKELY AT THIS TIME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1143 PM MDT SAT JUL 27 2013
TRICKY SET OF TAFS THROUGH THE PERIOD. THE SITE WITH THE MOST
VARIABLE AND LOWEST CONDITIONS SHOULD BE KGLD. WIDESPREAD LIGHT
-SHRA WITH EMBEDDED THUNDERSTORMS MOVING ACROSS THE AREA. LOOKS LIKE
MOST OF THE PRECIPITATION ENDS BY 12Z WITH THE BULK OF THE PRECIPITATION
STAYING SOUTH OF KMCK. SOME LINGERING SHOWERS MAY OCCUR THROUGH
MID MORNING. WITH PERSISTENT EASTERLY SURFACE WINDS AND MOIST LOW
LEVEL AIR MASS...WHEN THE PRECIPITATION LIGHTENS UP OR ENDS...MVFR
AND LOWER CONDITIONS HAVE OCCURRED OR ARE EXPECTED TO OCCUR IN
STRATUS AND FOG.
FROM MID MORNING THROUGH MOST OF THE REST OF THE PERIOD...MVFR
CEILINGS ARE EXPECTED WITH SOME SHOWER ACTIVITY EXPECTED TO
DEVELOP AGAIN IN THE AFTERNOON AND EVENING WITH KGLD HAVING THE
BEST CHANCE OF PRECIPITATION. HOWEVER DID NOT FEEL CONFIDENT
ENOUGH IN PUTTING IN PRECIPITATION THAT FAR OUT. ALSO POSSIBLE
THAT FOG MAY DEVELOP AGAIN AT THE END OF THIS PERIOD OR RIGHT
AFTER THIS PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...LOCKHART
LONG TERM...MK
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1155 PM MDT SAT JUL 27 2013
.UPDATE...
ISSUED AT 954 PM MDT SAT JUL 27 2013
JUST ISSUED ANOTHER UPDATE. INITIAL CHANGE WAS TO CANCEL THE
SEVERE THUNDERSTORM WATCH. DESPITE THAT...SHOWER/THUNDERSTORM
COVERAGE IS INCREASING OVER AND TO THE WEST OF THE FORECAST AREA.
COVERAGE OVER THE CWA IS ALONG PERSISTENT BOUNDARY. THESE STORMS
HAVE SHOWN A TENDENCY TO DEVELOP TOWARD THE WEST. COVERAGE TO THE
WEST INCREASING DUE TO INCOMING SHORTWAVE TROUGH AND RIGHT REAR
QUADRANT OF THE JET STAYING OVER THE AREA WELL INTO THE OVERNIGHT
HOURS.
ALSO PER EARLIER DISCUSSION...ELEVATED INHIBITION DECREASING AS
ELEVATED CAPE INCREASE THROUGH THE NIGHT. RUC CATCHING THE ABOVE
SCENARIO NICELY...WHICH PUTS A NICE SWATH OF PRECIPITATION DOWN
THE CENTER OF THE FORECAST AREA. PER THAT AND ABOVE MENTIONED
DATA/TRENDS...FELT GOOD IN INCREASING POPS TO LIKELY IN THE ABOVE
MENTIONED AREA THROUGH THE REST OF THE NIGHT. ALSO INCREASED SKY
COVER AGAIN. EVERYTHING ELSE LOOKS GOOD FOR NOW.
UPDATE ISSUED AT 817 PM MDT SAT JUL 27 2013
MESSY WEATHER/FORECAST SITUATION. ELEVATED BOUNDARY HAS KEPT
THUNDERSTORMS GOING OVER THE FAR EAST SINCE LATE THIS AFTERNOON.
RADAR HAS SHOWN TRENDS OF THIS DEVELOPING FURTHER WEST ALONG THIS
BOUNDARY. RUC HAS CAUGHT ONTO THIS. NEW DEVELOPMENT HAS OCCURRED
TO THE WEST IN ADVANCE OF A SHORTWAVE TROUGH. PLUS RIGHT REAR
QUADRANT STAYS NEAR OVER THE AREA THROUGH THE NIGHT. ALSO THE
ELEVATED CINH DECREASES TO NEXT TO NOTHING BY THE END OF THE NIGHT
WITH ELEVATED CAPE CONTINUING.
SO LIFT...INSTABILITY AND MOISTURE INCREASE THROUGH THE NIGHT. SO
INCREASED POPS TO TAKE THIS INTO ACCOUNT BUT MAY NOT HAVE GONE FAR
ENOUGH AND KEPT THE PREVAILING WEATHER AS THUNDERSTORMS. ALSO
UPPED QPF THROUGH THE NIGHT AS WELL. ALSO ADJUSTED WINDS PER
LATEST OBSERVATIONAL TRENDS AND MODEL DATA. ALSO INCREASED CLOUD
COVER AS WELL. LOOKING AT TOMORROW...THERE IS A LOT OF CLOUD COVER
ALONG WITH EASTERLY WINDS. CURRENT MODEL GUIDANCE IN DECENT
AGREEMENT WITH SOME PLACES NOT GETTING OUT OF THE 60S. SO ADJUSTED
TEMPERATURES DOWN A FEW DEGREES AND THAT MAY NOT BE ENOUGH.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 1235 PM MDT SAT JUL 27 2013
ISOLATED SHOWERS AND THUNDERSTORMS WILL CONTINUE TO STREAM ALONG
THE NORTHWEST FLOW ALOFT ACROSS THE NORTHEAST PORTION OF THE
FORECAST AREA THIS AFTERNOON. THUNDERSTORMS WILL BECOME MORE
NUMEROUS AND SCATTERED IN NATURE ACROSS THE FORECAST AREA AS THEY
BUILD OVER THE FRONT RANGE AND MOVE INTO THE AREA THIS LATE THIS
AFTERNOON AND EVENING. SOME STORMS ACROSS THE WESTERN PORTION OF
THE FORECAST AREA MAY BECOME SEVERE WITH DAMAGING WINDS AND LARGE
HAIL POSSIBLE. THUNDERSTORMS ARE EXPECTED TO CONTINUE THROUGH THE
LATE EVENING INTO THE OVERNIGHT HOURS WITH THE FOCUS REMAINING
IN THE VICINITY OF THE FRONTAL BOUNDARY AS THE SURFACE LOW
REMAINS IN THE SOUTHEAST COLORADO/PANHANDLE REGION IN RESPONSE TO
THE SHORT WAVE TROUGH THAT CUTS THROUGH THE CENTRAL ROCKIES ACROSS
THE UPPER RIDGE AND EMERGES OVER CENTRAL HIGH PLAINS SUNDAY
MORNING. MAIN AREA OF PRECIPITATION SHOULD SHIFT EAST OVERNIGHT
FROM EASTERN COLORADO TO CENTRAL KANSAS BY MID DAY ON SUNDAY.
HYDRO ISSUES MAY BECOME A CONCERN ACROSS THE SOUTHEASTERN SECTIONS
OF THE FORECAST AREA BY LATE SUNDAY IF MULTIPLE THUNDERSTORMS
CONTINUE TO MOVE ACROSS THE SAME AREA.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 145 PM MDT SAT JUL 27 2013
SUNDAY NIGHT-TUESDAY...PRECIPITATION CHANCES DECREASE FROM NORTHWEST
TO SOUTHEAST AS DRIER AIR AS LESS FAVORABLE DYNAMICS MOVE IN. SHOULD
HAVE A LULL IN PRECIPITATION CHANCES MONDAY TIL LATE IN THE
AFTERNOON WHEN ANOTHER WEAK SYSTEM MOVES INTO THE WESTERN 1/3 OR SO
OF THE AREA. THIS MAY PRODUCE A FEW THUNDERSTORMS THROUGH THE NIGHT
ACROSS THE NORTHWEST 1/2 OF THE AREA AS IT LIFTS NORTHEAST. FOR
TUESDAY CONTINUED CHANCES FOR PRECIPITATION.
LOWS SUNDAY NIGHT MID TO UPPER 50S WEST...AROUND 60 ELSEWHERE. FOR
MONDAY NIGHT UPPER 50S TO AROUND 60 WEST...LOW 60S ELSEWHERE. HIGHS
MONDAY 75 TO 80 IN THE MCCOOK TO NORTON AND HILL CITY AREAS WITH LOW
TO MID 80S ELSEWHERE. FOR TUESDAY HIGHS MID 80S TO AROUND 90.
WEDNESDAY-SATURDAY...UPPER FLOW STARTS TO BECOME MORE NORTHWESTERLY
WEDNESDAY AS THE UPPER HIGH STRENGTHENS TO OUR SOUTHWEST AND UPPER
TROUGH MOVES ASHORE ACROSS THE PACIFIC NORTHWEST. FOR THURSDAY
THROUGH SATURDAY UPPER FLOW BACKS TO THE SOUTHWEST THEN BECOMES
MORE WESTERLY TOWARDS THE END OF THE PERIOD. THIS TREND CONTINUES
THROUGH FRIDAY.
CONTINUES TO LOOK LIKE AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS JUST ABOUT EVERY DAY AS VARIOUS DISTURBANCES MOVE
ACROSS THE AREA.
HIGHS WEDNESDAY UPPER 80S TO AROUND 90...WARMING INTO THE LOW 90S
THURSDAY. SOME COOLER AIR MOVES DOWN ACROSS PARTS OF THE AREA FRIDAY
WITH UPPER 80S TO LOW 90S (NORTH TO SOUTH). FOR SATURDAY LOW TO MID
80S. LOWS GENERALLY IN THE 60S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1143 PM MDT SAT JUL 27 2013
TRICKY SET OF TAFS THROUGH THE PERIOD. THE SITE WITH THE MOST
VARIABLE AND LOWEST CONDITIONS SHOULD BE KGLD. WIDESPREAD LIGHT
-SHRA WITH EMBEDDED THUNDERSTORMS MOVING ACROSS THE AREA. LOOKS LIKE
MOST OF THE PRECIPITATION ENDS BY 12Z WITH THE BULK OF THE PRECIPITATION
STAYING SOUTH OF KMCK. SOME LINGERING SHOWERS MAY OCCUR THROUGH
MID MORNING. WITH PERSISTENT EASTERLY SURFACE WINDS AND MOIST LOW
LEVEL AIR MASS...WHEN THE PRECIPITATION LIGHTENS UP OR ENDS...MVFR
AND LOWER CONDITIONS HAVE OCCURRED OR ARE EXPECTED TO OCCUR IN
STRATUS AND FOG.
FROM MID MORNING THROUGH MOST OF THE REST OF THE PERIOD...MVFR
CEILINGS ARE EXPECTED WITH SOME SHOWER ACTIVITY EXPECTED TO
DEVELOP AGAIN IN THE AFTERNOON AND EVENING WITH KGLD HAVING THE
BEST CHANCE OF PRECIPITATION. HOWEVER DID NOT FEEL CONFIDENT
ENOUGH IN PUTTING IN PRECIPITATION THAT FAR OUT. ALSO POSSIBLE
THAT FOG MAY DEVELOP AGAIN AT THE END OF THIS PERIOD OR RIGHT
AFTER THIS PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...LOCKHART
LONG TERM...99
AVIATION...BULLER
AREA FORECAST DISCUSSION...UPDATED
NWS TOPEKA KS
1131 PM CDT SAT JUL 27 2013
.UPDATE...
ISSUED AT 1121 PM CDT SAT JUL 27 2013
LATEST GUIDANCE FROM THE 00Z PACKAGE COMBINED WITH THE RAP ARE
CONTINUING TO TREND SHOWERS AND STORMS DEVELOPING EARLIER ON
SUNDAY MORNING. WATER VAPOR IMAGERY IS DEPICTING A SHORTWAVE TROF
TRANSLATING SOUTHEAST OVER NEBRASKA WITH MID LEVEL ISENTROPIC LIFT
GENERATING STORMS OVER CENTRAL KS CONTINUING TO INCREASE AND LIFT
NORTHEAST TOWARDS THE CWA TONIGHT. HAVE THEREFORE INCREASED POPS
MAINLY OVER AREAS ALONG AND SOUTH OF INTERSTATE 70 THROUGH THE
MORNING AND AFTERNOON. HIGH TEMPERATURES ARE ALSO TRENDING COOLER
WITH THE PRECIP BANDS AND CLOUD COVER INCREASING THROUGHOUT THE
DAY. LATEST MOD GUIDANCE AGREED WITH THE DECISION TO LOWER HIGHS
DOWN INTO THE UPPER 60S WITH LOW 70S OVER FAR NORTHEAST KANSAS
WHERE HEAVIER SHOWERS ARE NOT EXPECTED.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 332 PM CDT SAT JUL 27 2013
WATER VAPOR IMAGERY SHOWING MID LEVEL MOISTURE HAS TEMPORARILY
ADVECTED BACK INTO THE AREA ON THE SOUTHERN PERIPHERY OF A VERY
STRONG JET. THE INCREASING SHEAR IN COMBINATION WITH WEAK ISENTROPIC
LIFT AND ELEVATED INSTABILITY...HAS LED TO REDEVELOPMENT OF
SHOWERS/ISOLATED THUNDER OVER THE SOUTHWEST HALF OF THE CWA THIS
AFTERNOON...BUT SHOULD DIMINISH THROUGH 6 PM. THE CLOUDCOVER AND
SCATTERED PRECIP HAS HELD TEMPS SO FAR TO THE MID 70S FAR NORTHEAST
CORNER TO THE MID 60S SOUTHWEST COUNTIES.
THE DEEPER MOISTURE TONIGHT WILL BE LOCATED PRIMARILY SOUTH AND WEST
OF THE COUNTY WARNING AREA THIS EVENING...THEN BEGIN TO ADVECT BACK
TO THE NORTHEAST LATER TONIGHT...BUT ESPECIALLY DURING THE DAY
SUNDAY. IN FACT PRECIPITABLE WATER VALUES ACROSS THE CWA INCREASE
FROM THE HALF TO AN INCH AND A HALF INCH RANGE NORTHEAST TO
SOUTHWEST RESPECTIVELY THIS EVENING TO AN INCH AND A HALF TO TWO
INCHES ACROSS THE ENTIRE CWA BY SUNDAY AFTERNOON. AS A RESULT...WILL
VERY GRADUALLY INCREASE SHOWER AND THUNDERSTORM CHANCES AGAIN
OVERNIGHT AND SUNDAY FROM SOUTHWEST TO NORTHEAST. THE HIGHEST
POPS...IN THE LIKELY CATEGORY...WILL BE ACROSS FAR SOUTHWEST
COUNTIES AND LINE UP WITH THE HIGHEST AMOUNTS OF QPF. TOTAL RAINFALL
ACROSS THE COUNTY WARNING AREA THROUGH SUNDAY AFTERNOON SHOULD RANGE
FROM ONLY A TRACE NORTH OF HIAWATHA TO NEARLY AN INCH IN SOUTHERN
DICKINSON COUNTY. HIGHS ON SUNDAY...SIMILAR TO TODAY...SHOULD BE
WITH THE THICKER CLOUDCOVER AND HIGHER PRECIP CHANCES OVER THE
WESTERN COUNTIES WITH READINGS IN THE LOWER 70S.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 332 PM CDT SAT JUL 27 2013
A MID LEVEL WAVE IS FORECAST TO MOVE ACROSS KANSAS SUNDAY NIGHT
WITH ANOTHER FOLLOWING BEHIND FOR MONDAY. INCREASING LOW LEVEL JET
WILL BRING AN INCREASE IN MOISTURE TRANSPORT INTO SOUTH CENTRAL
INTO NORTH CENTRAL KANSAS SUNDAY NIGHT. CONVECTION ACROSS CENTRAL
AND SOUTHERN KANSAS MAY IMPACT HEAVY RAINFALL POTENTIAL SOUTH OF
INTERSTATE 70. ISENTROPIC LIFT WILL ALSO CONTRIBUTE TO LIFT OVER
THE SOUTHERN CWA. FLASH FLOOD GUIDANCE RANGES FROM 2 TO AROUND 3
INCHES. AT THIS TIME WILL EMPHASIZE LOCALLY HEAVY RAINFALL SOUTH
OF I-70.
MONDAY AND MONDAY NIGHT ISENTROPIC LIFT WILL CONTINUE DURING THIS
PERIOD FOCUSING CONVECTION ALONG AND NORTH OF THE FRONT ACROSS EAST
CENTRAL KANSAS. MID LEVEL LIFT IS ALSO FORECAST TO INCREASE ACROSS
EASTERN KANSAS MONDAY NIGHT WITH A DEEPENING MID LEVEL WAVE. AGAIN
SOME LOCALLY HEAVY RAINFALL WILL BE POSSIBLE WITH TRAINING CELLS
ACROSS EAST CENTRAL KANSAS. MOISTURE TRANSPORT WILL ALSO INCREASE
AND FOCUS ACROSS EAST CENTRAL KANSAS INTO MISSOURI MONDAY NIGHT.
FORECAST SOUNDINGS ARE SATURATED WITH HIGH PRECIPITABLE WATER VALUES
OF 1.5 TO 2.5 INCHES.
FRONTAL BOUNDARY MOVES THROUGH TUESDAY WITH HIGH PRESSURE THEN
BUILDING LASTING THROUGH THURSDAY. NEXT CHANCE OF THUNDERSTORMS
COMES THURSDAY NIGHT WITH WARM ADVECTION. ANOTHER FRONTAL BOUNDARY
IS FORECAST LATE IN THE PERIOD FRIDAY INTO SATURDAY BRINGING ANOTHER
CHANCE OF THUNDERSTORMS.
TEMPERATURES WILL REMAIN IN THE 70S ON MONDAY WITH HIGHS WARMING
BACK INTO THE 80S TUESDAY WITH HIGHS NEAR 90 FRIDAY. COOLING OFF
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1121 PM CDT SAT JUL 27 2013
SHOULD SEE AN ACTIVE WEATHER PATTERN AT KTOP/KFOE/KMHK FOR THE NEXT
FORECAST PERIOD AS RAIN CHANCES INCREASE. VFR CLOUD COVER CONTINUES
TO SHIFT SOUTHEAST OVERNIGHT WITH INCREASING MOISTURE FROM THE
SOUTHWEST WILL BRING BANDS OF RAIN SHOWERS BEGINNING AT KMHK AFT 13Z
AND KTOP/KFOE AT 15Z. EMBEDDED ISOLATED THUNDER CANNOT BE RULED OUT
SO INSERTED A MENTION OF VCTS ATTM. SHORT RANGE MODELS ARE TRENDING
EARLIER THAN PREVIOUS RUNS SO ONSET TIMING MAY NEED TO BE REFINED
IN AMENDMENTS. WITH THE INCREASING MOISTURE AND ESPECIALLY
UNDERNEATH THE MODERATE RAIN BANDS...MVFR CONDITIONS ARE A
DEFINITE POSSIBILITY IN THE AFTERNOON AT TERMINALS. OVERNIGHT VRB
LIGHT WINDS SHIFT PREDOMINANTLY FROM THE EAST NEAR SUNRISE BLO 10
KTS.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BOWEN
SHORT TERM...63
LONG TERM...53
AVIATION...BOWEN
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1004 PM MDT SAT JUL 27 2013
.UPDATE...
ISSUED AT 954 PM MDT SAT JUL 27 2013
JUST ISSUED ANOTHER UPDATE. INITIAL CHANGE WAS TO CANCEL THE
SEVERE THUNDERSTORM WATCH. DESPITE THAT...SHOWER/THUNDERSTORM
COVERAGE IS INCREASING OVER AND TO THE WEST OF THE FORECAST AREA.
COVERAGE OVER THE CWA IS ALONG PERSISTENT BOUNDARY. THESE STORMS
HAVE SHOWN A TENDENCY TO DEVELOP TOWARD THE WEST. COVERAGE TO THE
WEST INCREASING DUE TO INCOMING SHORTWAVE TROUGH AND RIGHT REAR
QUADRANT OF THE JET STAYING OVER THE AREA WELL INTO THE OVERNIGHT
HOURS.
ALSO PER EARLIER DISCUSSION...ELEVATED INHIBITION DECREASING AS
ELEVATED CAPE INCREASE THROUGH THE NIGHT. RUC CATCHING THE ABOVE
SCENARIO NICELY...WHICH PUTS A NICE SWATH OF PRECIPITATION DOWN
THE CENTER OF THE FORECAST AREA. PER THAT AND ABOVE MENTIONED
DATA/TRENDS...FELT GOOD IN INCREASING POPS TO LIKELY IN THE ABOVE
MENTIONED AREA THROUGH THE REST OF THE NIGHT. ALSO INCREASED SKY
COVER AGAIN. EVERYTHING ELSE LOOKS GOOD FOR NOW.
UPDATE ISSUED AT 817 PM MDT SAT JUL 27 2013
MESSY WEATHER/FORECAST SITUATION. ELEVATED BOUNDARY HAS KEPT
THUNDERSTORMS GOING OVER THE FAR EAST SINCE LATE THIS AFTERNOON.
RADAR HAS SHOWN TRENDS OF THIS DEVELOPING FURTHER WEST ALONG THIS
BOUNDARY. RUC HAS CAUGHT ONTO THIS. NEW DEVELOPMENT HAS OCCURRED
TO THE WEST IN ADVANCE OF A SHORTWAVE TROUGH. PLUS RIGHT REAR
QUADRANT STAYS NEAR OVER THE AREA THROUGH THE NIGHT. ALSO THE
ELEVATED CINH DECREASES TO NEXT TO NOTHING BY THE END OF THE NIGHT
WITH ELEVATED CAPE CONTINUING.
SO LIFT...INSTABILITY AND MOISTURE INCREASE THROUGH THE NIGHT. SO
INCREASED POPS TO TAKE THIS INTO ACCOUNT BUT MAY NOT HAVE GONE FAR
ENOUGH AND KEPT THE PREVAILING WEATHER AS THUNDERSTORMS. ALSO
UPPED QPF THROUGH THE NIGHT AS WELL. ALSO ADJUSTED WINDS PER
LATEST OBSERVATIONAL TRENDS AND MODEL DATA. ALSO INCREASED CLOUD
COVER AS WELL. LOOKING AT TOMORROW...THERE IS A LOT OF CLOUD COVER
ALONG WITH EASTERLY WINDS. CURRENT MODEL GUIDANCE IN DECENT
AGREEMENT WITH SOME PLACES NOT GETTING OUT OF THE 60S. SO ADJUSTED
TEMPERATURES DOWN A FEW DEGREES AND THAT MAY NOT BE ENOUGH.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 1235 PM MDT SAT JUL 27 2013
ISOLATED SHOWERS AND THUNDERSTORMS WILL CONTINUE TO STREAM ALONG
THE NORTHWEST FLOW ALOFT ACROSS THE NORTHEAST PORTION OF THE
FORECAST AREA THIS AFTERNOON. THUNDERSTORMS WILL BECOME MORE
NUMEROUS AND SCATTERED IN NATURE ACROSS THE FORECAST AREA AS THEY
BUILD OVER THE FRONT RANGE AND MOVE INTO THE AREA THIS LATE THIS
AFTERNOON AND EVENING. SOME STORMS ACROSS THE WESTERN PORTION OF
THE FORECAST AREA MAY BECOME SEVERE WITH DAMAGING WINDS AND LARGE
HAIL POSSIBLE. THUNDERSTORMS ARE EXPECTED TO CONTINUE THROUGH THE
LATE EVENING INTO THE OVERNIGHT HOURS WITH THE FOCUS REMAINING
IN THE VICINITY OF THE FRONTAL BOUNDARY AS THE SURFACE LOW
REMAINS IN THE SOUTHEAST COLORADO/PANHANDLE REGION IN RESPONSE TO
THE SHORT WAVE TROUGH THAT CUTS THROUGH THE CENTRAL ROCKIES ACROSS
THE UPPER RIDGE AND EMERGES OVER CENTRAL HIGH PLAINS SUNDAY
MORNING. MAIN AREA OF PRECIPITATION SHOULD SHIFT EAST OVERNIGHT
FROM EASTERN COLORADO TO CENTRAL KANSAS BY MID DAY ON SUNDAY.
HYDRO ISSUES MAY BECOME A CONCERN ACROSS THE SOUTHEASTERN SECTIONS
OF THE FORECAST AREA BY LATE SUNDAY IF MULTIPLE THUNDERSTORMS
CONTINUE TO MOVE ACROSS THE SAME AREA.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 145 PM MDT SAT JUL 27 2013
SUNDAY NIGHT-TUESDAY...PRECIPITATION CHANCES DECREASE FROM NORTHWEST
TO SOUTHEAST AS DRIER AIR AS LESS FAVORABLE DYNAMICS MOVE IN. SHOULD
HAVE A LULL IN PRECIPITATION CHANCES MONDAY TIL LATE IN THE
AFTERNOON WHEN ANOTHER WEAK SYSTEM MOVES INTO THE WESTERN 1/3 OR SO
OF THE AREA. THIS MAY PRODUCE A FEW THUNDERSTORMS THROUGH THE NIGHT
ACROSS THE NORTHWEST 1/2 OF THE AREA AS IT LIFTS NORTHEAST. FOR
TUESDAY CONTINUED CHANCES FOR PRECIPITATION.
LOWS SUNDAY NIGHT MID TO UPPER 50S WEST...AROUND 60 ELSEWHERE. FOR
MONDAY NIGHT UPPER 50S TO AROUND 60 WEST...LOW 60S ELSEWHERE. HIGHS
MONDAY 75 TO 80 IN THE MCCOOK TO NORTON AND HILL CITY AREAS WITH LOW
TO MID 80S ELSEWHERE. FOR TUESDAY HIGHS MID 80S TO AROUND 90.
WEDNESDAY-SATURDAY...UPPER FLOW STARTS TO BECOME MORE NORTHWESTERLY
WEDNESDAY AS THE UPPER HIGH STRENGTHENS TO OUR SOUTHWEST AND UPPER
TROUGH MOVES ASHORE ACROSS THE PACIFIC NORTHWEST. FOR THURSDAY
THROUGH SATURDAY UPPER FLOW BACKS TO THE SOUTHWEST THEN BECOMES
MORE WESTERLY TOWARDS THE END OF THE PERIOD. THIS TREND CONTINUES
THROUGH FRIDAY.
CONTINUES TO LOOK LIKE AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS JUST ABOUT EVERY DAY AS VARIOUS DISTURBANCES MOVE
ACROSS THE AREA.
HIGHS WEDNESDAY UPPER 80S TO AROUND 90...WARMING INTO THE LOW 90S
THURSDAY. SOME COOLER AIR MOVES DOWN ACROSS PARTS OF THE AREA FRIDAY
WITH UPPER 80S TO LOW 90S (NORTH TO SOUTH). FOR SATURDAY LOW TO MID
80S. LOWS GENERALLY IN THE 60S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 542 PM MDT SAT JUL 27 2013
VFR CONDITIONS WILL START OUT THE TAF PERIOD AND THEN MVFR
CONDITIONS WILL PREVAIL DURING THE MORNING HOURS. LOW STRATUS AND
FOG ARE ALSO POSSIBLE IN THE MORNING DUE TO GOOD LOW LEVEL
MOISTURE AND THE COOLER AIR IN PLACE. HOWEVER...ONLY CHOSE TO GO
WITH MVFR IN THE MORNING EVEN THOUGH THE POSSIBILITY FOR IFR IS
THERE...JUST NOT CONFIDENT ENOUGH IN IFR AT THIS TAF ISSUANCE.
ALONG WITH LOW STRATUS AND FOG IN THE MORNING...A STRONG SHORTWAVE
WILL MOVE THROUGH AND BRING RAIN SHOWERS TO BOTH TAF SITES.
GUIDANCE SEEMED CONFIDENT IN BRINGING THIS INTO BOTH TAF SITES SO
WENT WITH A PREVAILING GROUP FOR -SHRA FOR KGLD AT 07Z AND KMCK AT
08Z LASTING THROUGH 15Z. ALSO INCLUDED 4SM VISIBILITY FOR ANY FOG
THAT MIGHT DEVELOP...THIS MAY CHANGE WITH THE NEXT TAF ISSUANCES.
THERE IS ANOTHER CHANCE FOR SHOWERS AND THUNDERSTORMS AFTER 15Z
TOMORROW...BUT NOT SURE WHERE THE COVERAGE WILL BE AT THIS TIME SO
LEFT OUT VCSH/VCTS FOR NOW.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...LOCKHART
LONG TERM...99
AVIATION...ALW
AREA FORECAST DISCUSSION
NWS JACKSON KY
142 AM EDT SUN JUL 28 2013
.UPDATE...
ISSUED AT 142 AM EDT SUN JUL 28 2013
JUST A FEW ISOLATED SHOWERS LEFT IN THE SOUTHEAST NEAR THE VIRGINIA
BORDER...BUT THESE SHOULD BE ALL GONE IN THE NEXT HOUR...LEAVING DRY
CONDITIONS IN PLACE FOR THE REST OF THE NIGHT. THERE HAVE BEEN SOME
REPORTS OF FOG IN THE WAKE OF THE RAIN WE SAW THIS EVENING AND LOOKS
REASONABLE TO PUT SOME FOG IN FOR THE AREAS WHICH SAW SOME RAIN...AT
LEAST FOR A PERIOD OVERNIGHT. DRY AIR ADVECTION SHOULD EVENTUALLY
KICK INTO GEAR WITH DEWPOINTS FALLING TOWARDS DAYBREAK. THIS WILL
ERODE THE FOG FAIRLY QUICKLY UPON DAYLIGHT. MADE SOME ADJUSTMENTS TO
TEMPERATURES AND DEWPOINTS TO REPRESENT CURRENT TRENDS.
OTHERWISE...WILL UPDATE TO REMOVE THE LAST OF THE RAIN FROM THE
FORECAST AND MODIFY THE BEST FOG AREAS.
UPDATE ISSUED AT 955 PM EDT SAT JUL 27 2013
SHOWERS HAVE BECOME MORE EXTENSIVE OVER THE NORTHERN PART OF THE
FORECAST AREA THIS EVENING. THERE HAVE ALSO BE SOME ISOLATED
THUNDERSTORMS. HAVE TIMED THIS AREA OF PRECIP ENE ACROSS THE
REGION...WITH LIKELY POPS IN THE PATH.
UPDATE ISSUED AT 637 PM EDT SAT JUL 27 2013
HAVE MODIFIED POP GRIDS FOR TONIGHT INTO SUNDAY MORNING...
INCORPORATING SOME TRENDS FROM THE RUC AND HRRR. THE SHORT TERM RAPID
UPDATE MODELS ARE SHOWING SHOWERS AND POSSIBLY THUNDERSTORMS
DEVELOPING ALONG AND JUST AHEAD OF THE COLD FRONT AS IT MOVES
IN...AND RADAR TRENDS EARLY THIS EVENING SEEM TO LEND SOME SUPPORT
TO THIS.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 245 PM EDT SAT JUL 27 2013
SHOWERS AHEAD OF THE COLD FRONT CONTINUE TO CROSS EASTERN KENTUCKY.
FRONT SCHEDULED TO CROSS TONIGHT AND SHOULD BE EAST OF THE STATE BY
SUN MORNING. THEN HIGH PRESSURE BUILDS DOWN FROM CANADA WITH A DRIER
AND COOLER AIR MASS. A FEW SHOWERS THIS EVENING COULD PRODUCE
THUNDER...BUT MOST SHOULD BE JUST LIGHT RAIN. RAINFALL TOTALS WILL
GENERALLY BE LESS THAN A QUARTER OF AN INCH. COOLER AIR WILL BE SLOW
TO INVADE SO OVERNIGHT LOWS WILL DROP TO THE 50S BUT WITH ENOUGH
REMAINING MOISTURE THAT VALLEY FOG MAY STILL BE A PROBLEM. THE COOLER
AIR WILL BATTLE ADDITIONAL SUNSHINE TO HOLD SUNDAY HIGHS TO THE UPPER
70S AND THEN WITH THE INFLUX OF DRIER AIR SUNDAY NIGHT LOWS WILL FALL
INTO THE LOWER 50S. EVEN A FEW UPPER 40S ARE NOT OUT OF THE QUESTION.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 249 PM EDT SAT JUL 27 2013
PERIOD WILL START OFF WITH UPPER LEVEL CLOSED LOW LIFTING TO THE NE
AND SURFACE HIGH PRESSURE SITTING OVERHEAD OF THE OHIO VALLEY. WITH
A STRONG JET IN THE UPPER LEVELS PULLING IN DRY AIR FROM THE
NE...ALONG WITH LIGHT NE WINDS AT THE SURFACE...EXPECT TEMPERATURES
TO REMAIN SLIGHTLY BELOW NORMAL AND HUMIDITY LEVELS TO BE LOW.
OVERALL IT WILL BE A BEAUTIFUL DAY WITH HIGH TEMPERATURES STILL
EXPECTED TO ONLY REACH NEAR 80...AND SLIGHTLY LOWER IN THE HIGHER
HILLS ALONG THE KY/VA BORDER. OVERNIGHT TEMPS WILL ONCE AGAIN DROP
DOWN TO BELOW NORMAL...POSSIBLY DROPPING LOWER THAN THE 60 DEGREE
MARK IN MANY LOCATIONS.
BY TUESDAY...HIGH PRESSURE OVER ERNY KY WILL PERSIST IN THE
MORNING/EARLY AFTERNOON WITH SIMILAR TEMPS AND LOW HUMIDITY VALUES.
BY LATE AFTERNOON/EVENING HOWEVER...THINGS WILL BEGIN TO CHANGE.
WHILE THE 500MB LOW CONTINUES TO LIFT NE...MUCH OF THE CONUS WILL
FIND ITSELF IN A MORE ZONAL FLOW. WITHIN THIS ZONAL FLOW A SHORTWAVE
WILL TRAVEL EASTWARD FROM THE COLORADO MOUNTAINS ON SUNDAY TO THE
OHIO VALLEY BY TUESDAY EVENING. THIS WILL TRANSLATE TO A SURFACE
BOUNDARY WHICH WILL PROGRESS WITH THE SYSTEM...AND TRAVERSE EASTERN
KY TUESDAY NIGHT/WEDNESDAY. AS HAS BEEN THE CASE IN PREVIOUS
FORECASTS...MODELS ARE STILL HAVING A HARD TIME COMING INTO
AGREEMENT ON THE EXACT TIMING OF THIS FRONTAL PASSAGE...ALONG WITH
THE TIMING AND COVERAGE OF THE ASSOCIATED CONVECTION. THE LAST TWO
RUNS OF THE GFS HAS SLOWED DOWN THE CONVECTION/S ARRIVAL IN EASTERN
KY UNTIL LATE WEDNESDAY NIGHT/EARLY WEDNESDAY MORNING. THE GEM IS
AGREEING MORE WITH THE GFS...BUT THE 0Z RUN OF THE ECMWF IS BOTH
FASTER IN TIMING AND HIGHER IN COVERAGE AND PRECIP AMOUNTS. SINCE
THIS IS DAY 4...THERE IS STILL PLENTY OF TIME FOR CHANGE AND BETTER
AGREEMENT WITH FUTURE MODEL RUNS...SO WILL CONTINUE WITH A CONSENSUS
AT THIS TIME ON PRECIP TIMING AND COVERAGE. REGARDLESS...NAM AND GFS
MODELS ARE IN GOOD AGREEMENT THAT HIGH LEVEL CLOUDS WILL START
MOVING ACROSS THE AREA AS EARLY AS LATE MONDAY NIGHT/TUESDAY
MORNING...WELL BEFORE ANY PRECIP STARTS. WINDS WILL ALSO TURN MORE
SRLY BY AFTERNOON...PULLING IN WARMER MOISTER AIR FROM THE SOUTH.
NOT ONLY WILL THIS HELP WITH THE PRECIP CHANCES TUESDAY
NIGHT/WEDNESDAY...BUT IT WILL ALSO MEAN THE RETURN OF A MORE HUMID
SUMMER AIR MASS.
AS FAR AS INSTABILITY DURING THE DAY WEDNESDAY...THERE REALLY ISN/T
MUCH. WINDS ARE SHOWING A DECENT VEERING PATTERN...ESPECIALLY IN THE
LOW LEVELS...BUT THE LAPSE RATES AND RESULTING POSITIVE ENERGY ARE
JUST NOT IMPRESSIVE. THE MAIN CONCERN IS THE AMOUNT OF MOISTURE
ASSOCIATED WITH THIS SYSTEM...WITH A SATURATED ATMOSPHERE AND PWAT
VALUES NEARING 1.5 TO 2.0 INCHES EVERY SIX HOURS ACCORDING TO THE
LATEST GFS RUN. WHILE AN EMBEDDED THUNDERSTORM IS NEVER OUT OF THE
QUESTION THIS TIME OF YEAR IN A MOIST AND WARM ENVIRONMENT...THE
MAIN CONCERN ON WEDNESDAY SHOULD JUST BE THE AMOUNT OF RAIN ACROSS
THE REGION AND THE POSSIBILITY FOR FLASH FLOODING AS A RESULT.
THE SURFACE BOUNDARY WILL CONTINUE TO PUSH OFF TO THE SE DURING THE
DAY THURSDAY...WITH PRECIP CHANCES EXPECTED TO CONTINUE THROUGHOUT
THE MORNING AND COME TO AN END DURING THE LATE AFTERNOON/EVENING
HOURS AS DRY AIR ALOFT BEGINS TO WORK IN ACROSS THE REGION AND MAKE
IT/S WAY DOWN TO THE SURFACE. FOR A FEW HOURS LATE THURS MORN/EARLY
AFTERNOON...DRY AIR ALOFT...LLVL MOISTURE...AND STEEPER LAPSE
RATES...WILL TRIGGER A BETTER CHANCE FOR SOME ISL/SCT THUNDERSTORM
DEVELOPMENT /ESPECIALLY IN THE EAST/. THE WINDOW FOR THIS HAPPENING
WILL BE CLOSED PRETTY QUICKLY THOUGH AS DRY AIR MAKES ITS WAY TO THE
SURFACE AND A LLVL INVERSION FORMS BY 0Z FRIDAY. THIS INVERSION AND
DRY AIR /HIGH PRESSURE/ WILL REMAIN IN PLACE THROUGHOUT THE DAY
FRIDAY AND INTO FRIDAY NIGHT. TEMPERATURES WILL BE ON AN INCREASING
TREND TUESDAY THROUGH THE END OF THE WEEK...WITH FRIDAY HAVING THE
HOTTEST TEMPS FORECASTED OF ANY OTHER DAY DURING THE FORECAST
PERIOD. HIGHS WILL TOP OUT IN THE MID 80S ON THIS DAY. BUT WITH A
DRY AIR MASS OVERHEAD AND WINDS ALOFT OUT OF THE NE...EXPECT THE
HUMIDITY LEVELS TO REMAIN AT BAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 142 AM EDT SUN JUL 28 2013
COLD FRONT IS MARCHING ACROSS EASTERN KENTUCKY PRESENTLY AND SHOULD
CLEAR THE SOUTHEAST PORTION OF THE AREA BY 09Z. THIS WILL BRING DRY
AIR ADVECTION INTO THE AREA FOR THE REMAINDER OF THE MORNING. UNTIL
THE FRONT PASSES...A PERIOD OF FOG CAN BE EXPECTED...CURRENTLY
IMPACTING KJKL. HOWEVER...THIS SHOULD BE VERY SHORT LIVED AS THE DRY
AIR ADVECTION KICKS IN AND WE SEE SOME SCT-BKN CLOUD COVER OVERSPREAD
THE AREA IN THE WAKE OF THE FRONT. CONDITIONS WILL TURN SOLIDLY VFR
AROUND OR SHORTLY AFTER DAYBREAK AS ANY FOG BURNS OFF. GOOD POTENTIAL
EXISTS FOR RIVER VALLEY FOG SUNDAY NIGHT...BUT WILL LIKELY HOLD OFF
UNTIL AFTER 06Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KAS
SHORT TERM...DUSTY
LONG TERM...JMW
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS CARIBOU ME
639 PM EDT SUN JUL 28 2013
.SYNOPSIS...
LOW PRESSURE WILL APPROACH TONIGHT AND THEN MOVE ACROSS THE REGION
MONDAY INTO TUESDAY. HIGH PRESSURE WILL RETURN ON WEDNESDAY.
&&
.NEAR TERM /THROUGH MONDAY/...
635 PM UPDATE...AN AREA OF SHOWERS WITH EMBEDDED THUNDERSTORMS IS
POSITIONED JUST OFF SHORE OF COASTAL WASHINGTON COUNTY AND HAS STUBBORNLY
REMAINED IN PLACE OVER THE PAST FEW HOURS. THE NEAR TERM FORECAST
MODELS, INCLUDING THE RUC AND HRRR, STILL INDICATE THAT THIS AREA
OF PRECIPITATION WILL LIFT NORTH AND ONSHORE LATER THIS EVENING.
HAVE THEREFORE KEPT SCATTERED SHOWERS IN THE FORECAST, BUT ADDED
SOME TIMING WORDING TO THE TEXT. CONDITIONS WILL BE MONITORED
CLOSELY SHOULD THIS ACTIVITY MAKE IT INTO WASHINGTON COUNTY, AS
ANY HEAVY RAIN COULD RESULT IN FLOODING ISSUES GIVEN THE VERY
HEAVY RAINFALL OF THE PAST FEW DAYS. OTHERWISE, A LOT OF THE
FORECAST AREA WILL REMAIN DRY FOR AT LEAST A FEW MORE HOURS, THEN
SCATTERED SHOWERS WILL DEVELOP BY AROUND MIDNIGHT OR SHORTLY
THEREAFTER. OTHER THAN ADJUSTMENTS MADE TO POPS, WEATHER, AND SKY
TO MATCH CURRENT RADAR/OBS/SATELLITE TRENDS, THE GOING FORECAST
LOOKS GOOD AND NO OTHER CHANGES WERE NEEDED.
PREVIOUS DISCUSSION...LOW PRESSURE WILL APPROACH FROM THE WEST
AND PASS TO THE NORTH LATE MONDAY. A COLD FRONT WILL APPROACH
FROM THE WEST BEHIND THE LOW IN THE AFTERNOON. THIS IS EXPECTED
TO PRODUCE THUNDERSTORMS ACROSS THE NORTH DURING THE AFTERNOON.
WILL US A BLEND OF THE NAM12...GFS40...SREF...CMCREG AND ECMWF TO
INITIALIZE THE POP...WEATHER AND QPF GRIDS. USED A BLEND OF THE
NAM12 AND MOSG25 FOR WIND GRIDS WITH 150 PERCENT OF SUSTAINED
WINDS FOR GUST SPEED. THE ALL BLEND USED FOR TEMPERATURE AND DEW
POINT GRIDS BASED ON VERIFICATION. DELINEATED FOG AREAS WITH
LAMP25.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
AN OCCLUDED FRONT WILL CONT TO BRING SHWRS AND EVE TSTMS TO MSLY
NRN PTNS OF THE FA MON NGT AS A S/WV ALF ROTATES SW TO NE FROM SRN
QB THRU NRN ME AND THEN TOWARD LABRADOR. KEPT CONTINUITY OF POPS
WITH PREV DAY PD BY CONTG LIKELY CVRG INTO THE EVE AND THEN SLOWLY
DIMINISHING TO SCT SHWRS LATE MON NGT.
TUE LOOKS TO BE MSLY CLDY N AND PTLY CLDY ACROSS THE S PTN OF THE
FA...WITH THE PASSAGE OF THE UPPER TROF AXIS FROM THE UPPER LOW
MOVG E THRU ERN QB KEEPING THE POTENTIAL OF INSTABILITY SHWRS
ACROSS THE NRN TWO THIRDS OF THE FA. WITH LIMITED SBCAPE OF UP TO
500 J/KG...CANNOT RULE OUT ISOLD AFTN/ERLY EVE TSTMS WITH THESE
SHWRS. HI TEMPS WILL BE A LITTLE BLO NORMAL DUE TO CLD CVR AND
SHWR CVRG SPCLY ACROSS THE N.
AFT A COOL NGT THAT WILL SEE ANY SHWR ACTIVITY DISSIPATE DURING THE
EVE HRS...WITH CLR TO PTLY CLDY SKIES LATE. WED SHOULD BE SUNNIER
AND WARMER WITH NEAR SEASONAL HI TEMPS AS AFTN 925-850 MB TEMPS WARM
A FEW DEG C WARMER THAN TUES. WITH LEFT OVR UPPER TROFINESS XNTDG
SW FROM THE UPPER LOW OVR LABRADOR...WE CANNOT RULE OUT AN ISOLD
AFTN SHWR ACROSS THE N.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AFT A FAIR NGT WITH SEASONAL LOW TEMPS...THU WILL BEGIN SUNNY WITH
SOME INCREASING CLDNSS LATE IN THE DAY. 925-850MB TEMPS SUGGEST
THU HI TEMPS TO BE THE WARMEST THIS UPCOMING WEEK...WITH MANY
LOWER ELEVATION LOCATIONS N OF THE IMMEDIATE COAST REACH 80 DEG F.
CANNOT RULE OUT SCT SHWRS REACHING FAR NW AND WRN PTNS OF THE FA
VERY LATE IN THE DAY...BUT FOR THE MOST PART SHWRS SHOULD HOLD OFF
FOR THE REST OF THE REGION TIL LATE THU NGT VIA THE CONSENSUS OF
MODEL SOLUTIONS. A CHC OF SHWRS AND MSLY AFTN TSTMS WILL CONT INTO
THE DAY FRI AS AN UPPER LVL TROF APCHS THE REGION FROM THE GREAT
LKS...ALG WITH SB CAPES OF 600-1200 J/KG. HI TEMPS WILL LIKELY BE
COOLER THAN THU DUE TO GREATER CLD CVR AND THE PRESENCE OF
SHWRS/TSTMS.
OTHERWISE THE CHC OD SHWRS WITH BKN-OVC CLD CVR ATTMS WILL
CONTINUE FRI NGT INTO THE WEEKEND AS AN UPPER LVL LOW FROM N CNTRL
CAN SETTLES IN ACROSS ERN QB...WITH SEVERAL S/WVS ROTATING ARND
THIS SYSTEM TO PRODUCE UNSETTLED CONDITIONS AND INTERMITTENT SHWRS.
FOR NOW...GIVEN TMG UNCERTAINTIES OF ANY PARTICULAR S/WV...WE KEPT
POPS IN THE CHC CATEGORY FRI AND FRI NGT AND SLOWLY DIMINISHED POPS
TO SLGT CHC SAT. WE ALSO LOWERED HI AND LOW TEMPS FOR SAT/SAT NGT
AND SUN/SUN NGT SEVERAL DEG FROM THE PREVIOUS UPDATE WITH THE
MODELS NOW SIG COOLER DUE TO THE CLOSER PROXIMITY OF THE UPPER LOW
FCST THIS WEEKEND. THIS ASPECT OF THE FCST IS THE MOST UNCERTAIN
ATTM...SINCE RECENT PRIOR MODEL RUNS WERE NOT AS DEEP OR S WITH
THE UPPER LOW/TROF XPCTD TO BE IN THE VICINITY OF THE REGION THIS
WEEKEND. IF THIS TREND HOLDS...WE WILL LIKELY HAVE TO LOWER FCST
HI TEMPS SAT AND SUN EVEN COOLER THAN WHAT WE SHOW THIS UPDATE.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
NEAR TERM: EXPECT MVFR/IFR CONDITIONS TO DEVELOP LATER TODAY AND
PERSIST THROUGH MONDAY.
SHORT TO LONG TERM: MVFR AND IFR CLG AND VSBY CONDITIONS XPCTD
MON NGT WITH SHWRS/SCT TSTMS/PATCHY FOG WITH CONDITIONS IMPROVING
TO VFR BY MIDDAY TUE ALL SITES WITH VFR CONT THRU EVE. THE NEXT CHC
OF MVFR CLGS AND VSBYS WILL BE LATE THU NGT INTO FRI WITH ANOTHER
ROUND OF SHWRS AND POSSIBLE TSTMS.
&&
.MARINE...
NEAR TERM: FOR WINDS WILL USE A BLEND OF THE NAM12 AND GFS40. FOR
WAVES: STILL LONG PERIOD WAVE LEFT OVER FROM FETCH AT BEGINNING OF
WEEKEND. TWO WAVE GROUPS PRESENT BOTH SOUTHERLY AND SOUTHEASTERLY
WAVES SYSTEMS. BOTH OF THESE WILL PRODUCE COMBINED SEAS AROUND 3
FEET THROUGH TONIGHT. ANOTHER SOUTHERLY FETCH WILL DEVELOP FROM
THE GULF OF MAINE SOUTHWARD LATER TONIGHT. THIS WAVE SYSTEM WILL
REINFORCE LONG PERIOD WAVE ALREADY IN PLACE BY LATE MONDAY. AT
PRESENT EXPECT WAVE HEIGHTS TO REMAIN BELOW 5 FEET THROUGH MONDAY.
SHORT TO LONG TERM: NO WIND/SEA HDLNS ANTICIPATED THRU THIS PTN OF
THE FCST WITH WW3/SWAN NAM BLEND FOR WVS TRIMMED ALG THE IMMEDIATE
COAST TO 1 TO 2 FT MOST PDS AND WV HTS OVR OUTER WATERS NO HIER THAN
4 FT ANY PD.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HASTINGS/MIGNONE
SHORT TERM...VJN
LONG TERM...PJR
AVIATION...HASTINGS/MIGNONE/VJN
MARINE...HASTINGS/MIGNONE/VJN
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
330 PM EDT SUN JUL 28 2013
.SYNOPSIS...
DRIER AND COOLER THAN NORMAL TEMPERATURES WILL BE THE RULE THROUGH
TUESDAY. THE NEXT WIDESPREAD CHANCE FOR RAIN WILL COME WEDNESDAY
NIGHT INTO THURSDAY.
&&
.NEAR TERM /THROUGH MONDAY/...
LOOKING UPSTREAM...CLOUD COVER WILL BE ON THE INCREASE FOR THE NEXT
FEW HOURS. UPPER LEVEL LOW CURRENTLY OVER NORTHERN LOWER MICHIGAN
WILL MAKE VERY SLOW PROGRESS TO THE NORTHEAST OVERNIGHT. RAIN
SHOWERS ACROSS LOWER MICHIGAN ARE ASSOCIATED WITH AN UPPER LEVEL
SHORTWAVE THAT IS EXPECTED TO TRACK FROM LOWER MICHIGAN TO LAKE ERIE
AND EVENTUALLY UP TO THE NORTHEAST. AS TODAY HAS PROGRESSED...MORE
RECENT RUNS OF THE RAP MODEL SHOW THE TRACK OF THE SHORTWAVE BEING
FARTHER NORTH THAN ORIGINALLY FORECAST. BETWEEN THAT AND THE EVENING
TIMING OF THE SHORTWAVE...APPROACHING LAKE ERIE BETWEEN 00Z AND
03Z...THINK THAT RAIN SHOWERS WILL ALREADY BE ON THE WANE AS THEY
PASS TO THE NORTH OF THE AREA. HAVE BACKED OFF CHANCE POPS TO SLIGHT
CHANCE POPS DURING THE EVENING. EXPECT PARTLY CLOUDY SKIES TO
CONTINUE OVERNIGHT WITH THE PRESENCE OF THE UPPER LOW.
AS THE UPPER LOW MOVES OUT ON MONDAY...MODELS ARE HINTING AT ONE
LAST TRAILING ROUND OF SHOWERS TO THE NORTH OF INTERSTATE 80. THERE
WILL BE VERY LITTLE MOISTURE TO WORK WITH...AND AM NOT CONVINCED
THAT THE SHOWERS WILL MATERIALIZE. CONSIDERING THE INHERITED FORECAST
WAS DRY...DO NOT HAVE THE CONFIDENCE TO ADD ANY POPS AT THIS
TIME...ALTHOUGH A SPRINKLE OR TWO CANNOT BE RULED OUT. TEMPERATURES
WILL BE COOL ONCE AGAIN TOMORROW...ABOUT 10 DEGREES BELOW NORMAL.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
HIGH PRESSURE WILL DOMINATE THE WEATHER PATTERN TUESDAY INTO
WEDNESDAY. THE NAM AND SREF APPEAR TO BE FAST OUTLIERS WITH THE NEXT
SYSTEM COMING IN. THE NAM ALSO APPEARED TO HAVE SOME CONVECTIVE
FEEDBACK ISSUES...WHICH COULD ACCOUNT FOR ITS OUTLIER STATUS.
GFS/ECMWF ARE SLOWER WITH THE TIMING OF THE SYSTEM...GENERALLY
KEEPING SHOWERS JUST SOUTH AND WEST OF THE REGION ON WEDNESDAY. HAVE
MADE LITTLE CHANGE TO THE TIMING OF POPS DURING THIS STRETCH. WITH
THE DEPARTURE OF THE UPPER LOW...ZONAL FLOW SHOULD ALLOW FOR
TEMPERATURES TO RISE A FEW DEGREES EACH DAY TOWARDS A RETURN TO MORE
SEASONABLE LEVELS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
MODELS HAVE ONCE AGAIN HAD TROUBLE AGREEING ON WHAT TO DO WITH
THE SURFACE LOW ON THURSDAY AND THE TRAILING COLD FRONT. FOR NOW
WILL MAKE ONLY MINOR CHANGES TO CURRENT FORECAST.
HIGH PRESSURE WILL MOVE BACK IN FOR THE END OF THE WEEK.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
VFR CONDITIONS EXPECTED THIS AFTERNOON...WITH WEST WINDS GUSTING
UP TO ABOUT 15KTS AND DIMINISHING AFTER SUNSET. DISTURBANCE
SWINGING THROUGH TONIGHT WILL BRING MID LEVEL CLOUDS TO THE AREA
AND ONLY A SLIGHT CHANCE OF A SHOWER IN NORTHERN PA.
OUTLOOK.../MONDAY NIGHT THROUGH FRIDAY/...
POSSIBLE NON- VFR WEDNESDAY AND THURSDAY WITH RAIN SHOWERS.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
742 PM EDT MON JUL 29 2013
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 251 PM EDT MON JUL 29 2013
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW CONFLUENT NW FLOW
ALF OVER THE WRN GRT LKS BTWN SLOWLY DEPARTING CUTOFF LO JUST S OF
JAMES BAY AND AN UPR RDG OVER MN. THE ARRIVAL OF SFC HI PRES/ACYC
FLOW AND DRIER AIRMASS SHOWN ON THE 12Z INL RAOB ARE BRINGING A
MOSUNNY DAY TO THE CWA. LOOKING UPSTREAM...A SHRTWV IS MOVING INTO
THE NRN PLAINS IN THE WSW FLOW ALF BTWN THE UPR RDG OVER MN AND A
TROF OVER SW CANADA. THERE ARE SOME SHRA/TS ASSOCIATED WITH THIS
FEATURE...AND SOME CLDS WELL IN ADVANCE OF THE SHRA ARE SPILLING
INTO MN.
MAIN FCST CONCERNS IN THE SHORT TERM ARE MIN TEMPS TNGT AND THE CHC
FOR SOME SHRA ON TUE.
TNGT...UPR RDG AXIS IS PROGGED TO DRIFT W-E OVER UPR MI TNGT.
FOLLOWING THE PASSAGE OF THE UPR RDG...SOME MSTR IN ADVANCE OF
SHRTWV MOVING INTO MN IS FCST TO SPREAD INTO THE WRN CWA. IN CONCERT
WITH INCRSG WSW FLOW AT H925 ON THE BACK SIDE OF RETREATING SFC HI
PRES TO THE E...THE FALL OF TEMP OVER THE NW PORTIONS OF THE CWA
SHOULD BE HELD IN CHECK A BIT. THE BEST CHC FOR MIN TEMPS FALLING
FARTHER INTO THE 40S WL BE OVER THE INTERIOR SCENTRAL AND E...WHERE
THE CLDS WL ARRIVE LATEST CLOSER TO THE RETREATING HI.
TUE...A NUMBER OF MODELS GENERATE SOME MAINLY LGT PCPN OVER UPR MI
AS SHRTWV DRIFTS TO THE E AND INTERACTS WITH MODEST RETURN OF
SOMEWHAT HIER H85 THETA E. SUSPECT THE BEST CHC FOR SOME SHRA WL BE
IN THE AFTN WITH DAYTIME HEATING AND SOME LLVL CNVGC ON LK BREEZE
BNDRYS. SYNOPTIC SCALE SW FLOW SHOULD LIMIT INLAND PENETRATION OF
BREEZE OFF LK SUP. SINCE MODEL FCST SDNGS CONTINUE TO EXHIBIT
RELATIVELY WARM MID LVLS TEMPS/SOME CAPPING AOA H7/MARGINAL MID LVL
LAPSE RATES...WENT NO HIER THAN SCHC POPS AND KEPT OUT THE MENTION
OF TS FOR NOW WITH LIMITED INSTABILITY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 344 PM EDT MON JUL 29 2013
WE WILL START THIS LONG TERM PERIOD OUT WITH WESTERLY FLOW AT
500MB...WITH A RIDGE STUCK ACROSS THE SOUTHERN U.S. AND THE NEXT OF
A SERIES OF LOWS SET UP ACROSS MANITOBA.
THE 500MB LOW OVER MANITOBA WILL SHIFT ACROSS WESTERN AND CENTRAL
ONTARIO WEDNESDAY AS THE SFC RIDGE OVERHEAD EXITS TO THE SE. 850MB
TEMPS IN DECENT WAA BEHIND THE RIDGE SHOULD RISE TO AROUND 13C
BEFORE COLD FRONT SWEEPS IN FROM THE WNW DURING THE AFTERNOON AND
EARLY EVENING HOURS. TIMING LOOKS TO BE SIMILAR WITH THE AVAILABLE
MODEL GUIDANCE...WITH SHOWERS AND THUNDERSTORMS REMAINING MAINLY TO
OUR W OR OVER LAKE SUPERIOR THROUGH 12Z WEDNESDAY...AROUND 0.25IN
OVER THE W TIER OF COUNTIES BY 18Z...AND CENTRAL AND E DURING THE
MID TO LATE AFTERNOON HOURS. THERE ARE A COUPLE OF OUTLIERS. THE
29/12Z REGIONAL WRF AND CANADIAN RUNS WERE EITHER TOO STRONG OR TOO
WEAK WITH THE SHORTWAVES ROTATING THROUGH...AS THE 500MB TROUGH
BEGINS TO SWING INTO UPPER MI ON WEDNESDAY. VARIABLE PRECIPITATION
OUTPUTS OF NEARLY NOTHING TO AROUND AN INCH WERE THE RESULT. THE WRF
AND CANADIAN RUNS WERE EXCLUDED FROM MUCH OF THIS FCST...GIVEN THE
LOWER CONFIDENCE IN EITHER SOLUTION.
EXPECT THE COLD FRONT TO BE OVER FAR EASTERN UPPER MI BY 06Z
THURSDAY...WITH COOLER AIR FILTERING IN FROM THE NW ONCE AGAIN.
850MB TEMPS SHOULD FALL TO AROUND 8C BY DAYBREAK THURSDAY...WITH
LOWS NEAR 50F OVER THE W HALF OF UPPER MI WITH W WINDS HOVERING NEAR
10KTS.
NO REAL WARM UP IS EXPECTED FOR THURSDAY THROUGH THE UPCOMING
WEEKEND AS A SERIES OF DISTURBANCES SWINGING IN FROM THE NW HELP
KEEP THEM IN CHECK. THERE COULD BE SOME POP UP AFTERNOON SHOWERS OR
EVEN A THUNDERSTORM THURSDAY AFTERNOON INLAND FROM LAKE
SUPERIOR...AS ANOTHER SHORTWAVE ROTATES AROUND THE MAIN 500MB LOW
STUCK NEAR AND ACROSS HUDSON BAY. A SLIGHTLY MORE SIGNIFICANT SFC
TROUGH/500MB SHORTWAVE WILL SLIDE ACROSS FRIDAY AFTERNOON...WITH
ADDITIONAL CLOUD COVER...SHOWERS...AND INLAND POP UP THUNDERSTORMS.
YET ANOTHER ROUND OF SHOWERS WILL BE POSSIBLE SATURDAY...ALTHOUGH
LIKELY FARTHER EAST AS THE ENTIRE SYSTEM SHIFTS EASTWARD AND THE SFC
RIDGE BEGINS TO SHIFT IN. EXPECT DRY WEATHER SUNDAY AS THE SFC HIGH
PUSHES OVERHEAD...EVEN THROUGH NW FLOW LINGERS ALOFT. WITH THE
29/12Z ECMWF SHOWING 850MB TEMPS ON AROUND 7C AND LIGHT N
WINDS...60S AND LOW 70S STILL LOOK REASONABLE FOR HIGH TEMPS. AS FOR
DAY 7/MONDAY...THE SFC HIGH DOES NOT LOOK TO MOVE MUCH...BUT A WAVE
SLIDING THROUGH THE NW FLOW COULD BRING A PARTLY CLOUDY SKY TO THE W
WITH A FEW SHOWERS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 742 PM EDT MON JUL 29 2013
VFR CONDITIONS WILL PREVAIL THRU THE FCST PERIOD AT KIWD/KCMX/KSAW.
A DISTURBANCE CURRENTLY OVER THE NRN PLAINS WILL PASS ACROSS THE
UPPER GREAT LAKES TUE...BRINGING LOWER CLOUDS DOWN TO AROUND 5KFT
ALONG WITH THE POSSIBILITY OF A FEW -SHRA. INCLUDED VCSH IN THE
MORNING AT KIWD WITH DECENT MODEL AGREEMENT FOR SOME SHRA TO REACH
WRN UPPER MI. AT KCMX/KSAW...CONFIDENCE IS LOWER THAT ANY SHRA WILL
OCCUR AT OR IN THE VCNTY AS DISTURBANCE WILL BE WEAKENING. SO...NO
PCPN WAS MENTIONED FOR NOW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 251 PM EDT MON JUL 29 2013
EXPECT WINDS NO HIER THAN 20 KTS THIS FORECAST PERIOD WITH WEAK PRES
GRADIENT DOMINATING THE UPPER GREAT LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...ROLFSON
MARINE...KC
AREA FORECAST DISCUSSION
NWS DULUTH MN
848 PM CDT MON JUL 29 2013
.UPDATE...
AT 845PM/145Z...SURFACE HIGH PRESSURE WAS CENTERED NEAR THE
SOUTHERN GREAT LAKES. A TROUGH OF LOW PRESSURE WAS ORIENTATED FROM
NORTH TO SOUTH THROUGH CENTRAL MANITOBA THROUGH THE CENTRAL
DAKOTAS. THERE WERE SPRINKLES & LIGHT RAIN SHOWERS SOUTH OF THE
BRAINERD LAKES REGION AND HINCKLEY AREAS...WHICH WAS ASSOCIATED
WITH MID LEVEL CLOUDS WITH A PASSING WEAK SHORTWAVE. THERE WAS A
MUCH STRONGER SHORTWAVE IN NORTH CENTRAL NORTH DAKOTA HEADING
EAST. SHOWERS AND STORMS WERE MOVING THROUGH SOUTHERN MANITOBA AND
EASTERN NORTH DAKOTA AHEAD OF THE APPROACHING TROUGH. MUCH OF THE
NORTHLAND HAD PARTLY TO MOSTLY CLEAR SKIES...EXCEPT FOR MOSTLY
CLOUDY SKIES ACROSS THE SOUTHERN FRINGE OF THE FORECAST AREA NEAR
THE SHOWERS WITH THE WEAK SHORTWAVE. MOSTLY TO FULLY CLOUDY SKIES
COVERED MUCH OF EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA...AND
THOSE CLOUDS WERE HEADING EAST TOWARDS THE NORTHLAND. THE
NORTHLAND HAD TEMPERATURES RANGING FROM THE MID 50S TO UPPER 60S.
BASED ON THE LATEST TRENDS AND HIGH RESOLUTION MODELS...IT APPEARS
THE PREVIOUS FORECAST NEEDED SIGNIFICANT TWEAKS TO INCREASE CLOUD
COVER AND PCPN CHANCES FOR LATER TONIGHT AND INTO TUESDAY MORNING.
THE RAP13 AND HRRR ARE INDICATING THAT THERE WILL BE A LOT OF
INCREASING LOW/MID LEVEL HUMIDITY WITH THE LIGHT SOUTHERLY FLOW AS
THE TROUGH APPROACHES TONIGHT. THIS SHOULD RESULT IN INCREASING
CLOUD COVER. THOSE MODELS ARE ALSO INDICATING SCATTERED SHOWERS
WILL DEVELOP OVER MUCH OF THE NORTHLAND BY LATE TONIGHT AND THEN
BEGIN TO TAPER OFF AND/OR MOVE OUT OF THE NORTHLAND LATER TUESDAY
MORNING. THERE SEEMS TO BE LITTLE SUPPORT IN CAPE AND SHEAR IN THE
MODELS TO CONTINUE CARRYING ISOLATED THUNDER THROUGH THE
NIGHT...SO I ONLY FORECAST RAIN SHOWERS.
I ALSO INCREASED THE LOW TEMPERATURES A BIT BECAUSE OF THE
EXPECTED INCREASE IN CLOUD COVER.
&&
.PREV DISCUSSION... /ISSUED 626 PM CDT MON JUL 29 2013/
AVIATION.../00Z TAF ISSUANCE/
THERE WILL BE INCREASING LOW/MID LEVEL MOISTURE THIS EVENING AND
OVERNIGHT ACROSS NE MINNESOTA AND NW WISCONSIN WITH THE LIGHT
SOUTHERLY FLOW AHEAD OF AN APPROACHING TROUGH OF LOW PRESSURE
CURRENTLY IN THE DAKOTAS. THIS INCREASING MOISTURE WILL LIKELY
RESULT IN A PERIOD OF MVFR CIGS FOR KINL/KBRD/KHIB/KDLH/KHYR LATER
TONIGHT AND THROUGH PART OF TUESDAY MORNING BEFORE SCATTERING OR
MOVING OUT OF THE REGION LATE TUESDAY MORNING OR BY NOON. THERE
COULD BE SOME LIGHT RAIN SHOWERS DURING THIS PERIOD TOO. THE MVFR
CIGS SHOULD DEVELOP AT KINL/KBRD LATE THIS EVENING...AND THEN
SPREAD EAST TO KHIB/KDLH/KHYR LATE TONIGHT. VFR CONDITIONS ARE
LIKELY ACROSS THE REGION TUESDAY AFTERNOON.
PREV DISCUSSION... /ISSUED 322 PM CDT MON JUL 29 2013/
SHORT TERM...TONIGHT...
HIGH PRESSURE OVER THE GREAT LAKES WILL CONTINUE TO MOVE TO THE EAST
TONIGHT BRINGING SOUTHERLY WINDS AND MILDER CONDITIONS TO THE
NORTHLAND TONIGHT. TEMPERATURES WILL BE MAINLY IN THE LOWER 50S
OVERNIGHT. A SHORTWAVE WILL APPROACH FROM THE NORTHERN GREAT PLAINS
LATE TONIGHT AND BRING A CHANCE OF SHOWERS AND SOME THUNDERSTORMS TO
THE WESTERN PART OF THE FORECAST AREA...MAINLY AROUND MIDNIGHT. HIGH
RESOLUTION MODELS TRENDING A LITTLE FASTER BRINGING IN THE
PRECIPITATION AFTER 4Z FROM THE BRAINERD LAKES REGION TO THE
BORDERLAND. RAINFALL AMOUNTS LOOK TO BE UNDER A TENTH OF AN INCH BY
TUESDAY MORNING.
LONG TERM...TUESDAY THROUGH SATURDAY...
WESTERLY FLOW ALOFT TUESDAY WILL CARRY A WEAK MID LVL SHORTWAVE TROF
ACROSS THE REGION WITH SCTD LIGHT PRECIP. THE UPPER SHORTWAVE TROF
WILL OUTRUN THE LOW LVL FRONTAL SYSTEM. THE ASSOCIATED LOW LVL
FRONTAL SYSTEM WILL ENTER THE REGION TUESDAY NIGHT AS REFLECTED IN
THE LOW LVL THETAE FIELDS AND A DISTINCT SHIFT TO NW BDRY LAYER
FLOW. THIS FRONTAL PASSAGE WILL BE ACCOMPANIED BY A HIGHER PROB OF
PRECIP AS FRONTAL CONVERGENCE COMBINES WITH A STRONGER SHORTWAVE
ALOFT AND A SECONDARY PWAT AXIS. THIS FROPA WILL HERALD THE
AMPLIFICATION OF THE UPPER FLOW WEDNESDAY AFTN WHICH WILL CONTINUE
INTO THE WEEKEND. AS UPPER FLOW DEEPENS AND MEAN LAYER RH INCREASES
THUR/FRI AN OPPORTUNITY FOR SHOWERS WILL ARISE. NOT CONFIDENT ON HOW
FAR SOUTH THE POPS WILL OCCUR. HAVE STARTED WITH ARROWHEAD AND NRN
WISC..SPREADING INTO SERN CWA FRIDAY. LOW LVL THERMAL FIELDS SUGGEST
ANOTHER COLD FRONT WILL SWEEP ACROSS THE REGION FRIDAY. LARGE SFC
HIGH WILL MOVE FROM MANITOBA INTO NORTHLAND SATURDAY AND EARLY
SUNDAY. THE SFC HIGH IS FCST TO SHIFT EAST OF THE REGION SUNDAY
EVENING. A SLIGHT CHC THAT SOME PRECIP AMY ARRIVE LATE SUNDAY OVER
SWRN CORNER OF CWA IN RESPONSE TO WARM ADVECTION REGIME FROM NRN
PLAINS SYSTEM. TEMPS WILL RUN BLO CLIMO FOR MOST OF THIS PERIOD.
&&
.POINT TEMPS/POPS...
DLH 58 75 58 72 / 40 30 50 60
INL 54 77 55 71 / 40 40 50 10
BRD 58 77 59 76 / 40 20 60 40
HYR 55 74 59 75 / 40 30 30 60
ASX 54 74 59 73 / 30 30 30 60
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...GROCHOCINSKI
AREA FORECAST DISCUSSION
NWS BILLINGS MT
855 AM MDT SUN JUL 28 2013
.UPDATE...
GOING FORECAST APPEARS IN GOOD SHAPE OVERALL...THEREFORE NO
CHANGES FOR THE UPDATE. THE INHERITED MAX TEMP HAS ME
NERVOUS...BUT CLEARING SHOULD ALLOW FOR A QUICK WARM
UP...ESPECIALLY WITH WARMER START TO THE DAY. PRECIP POTENTIAL
LOOKS ON TRACK AS WELL...SO NO CHANGES FOR THIS MORNING. AAG
&&
.SHORT TERM...VALID FOR TDY AND MON...
SHORTWAVE...SEEN ON WATER VAPOR IMAGERY AND RAP MODEL...WAS
MOVING ACROSS THE AREA EARLY THIS MORNING GENERATING SOME SHOWERS
AND THUNDERSTORMS. WILL NEED TO WATCH THE EASTERN PORTION OF THE
FORECAST AREA AS STORMS CONTINUE MOVING E AS MESOANALYSIS SHOWED
30 TO 40 KT OF SHEAR THERE.
UPPER LOW SPINNING OVER ALBERTA THIS MORNING ON WATER VAPOR
IMAGERY WILL CONTINUE TO SEND SHORTWAVES THROUGH THE REGION. JET
ENERGY WILL ALSO PROVIDE UPPER DIVERGENCE THROUGH THE PERIOD.
UPPER DIFLUENCE WILL ALSO CONTRIBUTE TO LIFT TODAY AND
TONIGHT. PRECIPITABLE WATERS WILL BE HIGHEST E OF KBIL THROUGH THE
PERIOD WITH VALUES OVER AN INCH. A LOW LEVEL JET WILL BE PRESENT
OVER THE EASTERN ZONES THROUGH THIS EVENING AS WELL. SURFACE ANALYSIS
SHOWED A SURFACE LOW N OF KBIL AT 08Z AND A COLD FRONT MOVING
SLOWLY E THROUGH WESTERN MT.
DUE TO THE ABOVE...HAVE INCREASED POPS ACROSS THE AREA THIS
MORNING...AND OVER THE E THIS AFTERNOON. INSTABILITY PROFILES
SHOWED 500-1000 J/KG OF SURFACE CAPE LATE THIS AFTERNOON INTO THIS
EVENING E OF KBIL AND MODELS HAD 35 TO 40 KT OF BULK SHEAR. THUS
WILL MENTION STRONG WINDS AND SMALL HAIL WITH THUNDERSTORMS OVER
THE E. FROM KBIL W...INVERTED-V SOUNDINGS SUPPORTED GUSTY WINDS
WITH THUNDERSTORMS. CONTINUED THE HIGH POPS ALONG THE EASTWARD MOVING
COLD FRONT THIS EVENING. BEST CHANCES FOR PRECIPITATION WILL BE
OVER THE FAR EASTERN ZONES ON MON ALONG THE COLD FRONT SO HAVE
RAISED POPS THERE. AN INVERTED SURFACE TROUGH WILL KEEP LOW
CHANCES OF PRECIPITATION ACROSS THE AREA MON NIGHT. THE HIGH
PRECIPITABLE WATERS E OF KBIL WILL SUPPORT POSSIBLE HEAVY RAINFALL
WITH THUNDERSTORMS THROUGH THE PERIOD.
GOOD MIXING ON BUFKIT SOUNDINGS SUPPORTED THE GOING HIGH
TEMPERATURES TODAY. MIXING WILL NOT BE AS GOOD FOR MON AND
TEMPERATURE FORECAST APPEARED ON TRACK. ARTHUR
.LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT...
MODELS HAVE CHANGED IT UP A LITTLE BIT ON THE EXTENDED PERIOD BUT
THE OVERALL FEEL IS THE SAME. THE PATTERN STILL LOOKS QUITE
UNSETTLED WITH MANY CHANCES FOR CONVECTION THROUGH NEXT WEEKEND.
A SHORTWAVE IS PROGGED TO MOVE ACROSS THE AREA TUESDAY AFTERNOON
AND EVENING. EASTERLY LOW LEVEL WINDS WILL KEEP DEWPOINTS IN THE
LOWER 50S FOR MOST LOCATIONS. MONSOON MOISTURE WILL BE PULLED
ACROSS THE REGION IN SOUTHWEST FLOW ALOFT. THIS WILL COMBINE WITH
A MOIST...PRECIPITABLE WATERS AROUND AN INCH...AND UNSTABLE
AIRMASS TO TRIGGER SCATTERED CONVECTION. THE STORMS SHOULD BE WET
AS THE ATMOSPHERIC COLUMN MOISTENS UP.
THE MODELS HAVE DIVERGED FROM PREVIOUS SOLUTIONS FOR WEDNESDAY.
THE CONSENSUS NOW IS TO BUILD A RIDGE UP OVER SOUTHERN MONTANA AS
A DEEP TROUGH APPROACHES THE PACIFIC NORTHWEST COAST. THIS WOULD
PUSH STRONGER FORCING NORTH. WILL HAVE TO WATCH THIS TREND AS MAY
NEED TO LOWER POPS...BUT WILL LEAVE SCATTERED POPS IN FOR NOW AS
HIGH PRECIPITABLE WATER AMOUNTS TEND TO LEAD TO EASY CONVECTIVE
DEVELOPMENT.
THE WESTERN UPPER TROUGH MOVES INLAND ON THURSDAY AND SETS UP
SOUTHWEST FLOW FOR THURSDAY AND FRIDAY. THE FLOW WAS PROGGED TO BE
MOIST AND UNSTABLE AND DIVERGENT...SO THIS LOOKS LIKE THE BEST
PERIOD FOR PRECIPITATION. MAY HAVE TO RAISE POPS FURTHER AS THE
DAY APPROACHES...BUT SCATTERED POPS SHOULD COVER THINGS FOR NOW.
THE ECMWF POINTS TO THE UNSETTLED PATTERN SHUTTING OFF SUNDAY AS
THE STRONG SOUTHERN PLAINS RIDGE BUILDS NORTH. THE GFS HAS THE
SAME IDEA...JUST NOT AS AGGRESSIVE ON BUILDING HEIGHTS.
TEMPERATURES WILL BE HELD BELOW SEASONAL AVERAGES THROUGH THE
ENTIRE EXTENDED PERIOD. THIS DUE TO LOW HEIGHTS...LOW LEVEL EAST
TO NORTHEAST WIND...AND HIGH MOISTURE CONTENT IN THE ATMOSPHERE.
TWH
&&
.AVIATION...
WIDELY SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE
ACROSS THE FORECAST AREA THIS MORNING. BETTER CHANCES FOR SHOWERS
AND THUNDERSTORMS CAN BE EXPECTED THIS AFTERNOON INTO THIS
EVENING. HEAVY RAIN AND GUSTY WINDS WILL ACCOMPANY ANY
THUNDERSTORM. AN ISOLATED SEVERE THUNDERSTORM CONTAINING LARGE
HAIL WILL BE POSSIBLE TOWARD THE DAKOTA BORDER THIS
AFTERNOON/EVENING. MVFR TO IFR CONDITIONS WILL BE POSSIBLE WITH
ANY SHOWER/THUNDERSTORM. OTHERWISE...VFR CONDITIONS WILL PREVAIL
THROUGH THIS EVENING. HOOLEY
&&
.PRELIMINARY POINT TEMP/POPS...
TDY MON TUE WED THU FRI SAT
-------------------------------------------------------
BIL 081 059/080 058/084 059/085 061/082 059/081 059/083
4/T 53/T 32/T 33/T 44/T 43/T 33/T
LVM 084 051/079 049/083 049/084 051/079 050/079 050/080
4/T 53/T 23/T 33/T 44/T 43/T 33/T
HDN 085 059/082 058/085 059/087 059/084 059/083 059/085
5/T 64/T 32/T 33/T 44/T 43/T 33/T
MLS 085 060/082 060/085 060/086 061/084 060/082 061/085
5/T 74/T 33/T 33/T 44/T 43/T 33/T
4BQ 084 056/082 058/085 058/085 058/084 059/081 059/084
5/T 55/T 33/T 33/T 44/T 43/T 33/T
BHK 079 056/078 056/080 056/081 058/080 057/079 057/081
4/T 55/T 33/T 32/T 44/T 43/T 34/T
SHR 084 055/081 055/085 055/085 056/083 055/080 055/083
5/T 64/T 32/T 33/T 34/T 43/T 33/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
310 AM MDT SUN JUL 28 2013
.SHORT TERM...VALID FOR TDY AND MON...
SHORTWAVE...SEEN ON WATER VAPOR IMAGERY AND RAP MODEL...WAS
MOVING ACROSS THE AREA EARLY THIS MORNING GENERATING SOME SHOWERS
AND THUNDERSTORMS. WILL NEED TO WATCH THE EASTERN PORTION OF THE
FORECAST AREA AS STORMS CONTINUE MOVING E AS MESOANALYSIS SHOWED
30 TO 40 KT OF SHEAR THERE.
UPPER LOW SPINNING OVER ALBERTA THIS MORNING ON WATER VAPOR
IMAGERY WILL CONTINUE TO SEND SHORTWAVES THROUGH THE REGION. JET
ENERGY WILL ALSO PROVIDE UPPER DIVERGENCE THROUGH THE PERIOD.
UPPER DIFLUENCE WILL ALSO CONTRIBUTE TO LIFT TODAY AND
TONIGHT. PRECIPITABLE WATERS WILL BE HIGHEST E OF KBIL THROUGH THE
PERIOD WITH VALUES OVER AN INCH. A LOW LEVEL JET WILL BE PRESENT
OVER THE EASTERN ZONES THROUGH THIS EVENING AS WELL. SURFACE ANALYSIS
SHOWED A SURFACE LOW N OF KBIL AT 08Z AND A COLD FRONT MOVING
SLOWLY E THROUGH WESTERN MT.
DUE TO THE ABOVE...HAVE INCREASED POPS ACROSS THE AREA THIS
MORNING...AND OVER THE E THIS AFTERNOON. INSTABILITY PROFILES
SHOWED 500-1000 J/KG OF SURFACE CAPE LATE THIS AFTERNOON INTO THIS
EVENING E OF KBIL AND MODELS HAD 35 TO 40 KT OF BULK SHEAR. THUS
WILL MENTION STRONG WINDS AND SMALL HAIL WITH THUNDERSTORMS OVER
THE E. FROM KBIL W...INVERTED-V SOUNDINGS SUPPORTED GUSTY WINDS
WITH THUNDERSTORMS. CONTINUED THE HIGH POPS ALONG THE EASTWARD MOVING
COLD FRONT THIS EVENING. BEST CHANCES FOR PRECIPITATION WILL BE
OVER THE FAR EASTERN ZONES ON MON ALONG THE COLD FRONT SO HAVE
RAISED POPS THERE. AN INVERTED SURFACE TROUGH WILL KEEP LOW
CHANCES OF PRECIPITATION ACROSS THE AREA MON NIGHT. THE HIGH
PRECIPITABLE WATERS E OF KBIL WILL SUPPORT POSSIBLE HEAVY RAINFALL
WITH THUNDERSTORMS THROUGH THE PERIOD.
GOOD MIXING ON BUFKIT SOUNDINGS SUPPORTED THE GOING HIGH
TEMPERATURES TODAY. MIXING WILL NOT BE AS GOOD FOR MON AND
TEMPERATURE FORECAST APPEARED ON TRACK. ARTHUR
.LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT...
MODELS HAVE CHANGED IT UP A LITTLE BIT ON THE EXTENDED PERIOD BUT
THE OVERALL FEEL IS THE SAME. THE PATTERN STILL LOOKS QUITE
UNSETTLED WITH MANY CHANCES FOR CONVECTION THROUGH NEXT WEEKEND.
A SHORTWAVE IS PROGGED TO MOVE ACROSS THE AREA TUESDAY AFTERNOON
AND EVENING. EASTERLY LOW LEVEL WINDS WILL KEEP DEWPOINTS IN THE
LOWER 50S FOR MOST LOCATIONS. MONSOON MOISTURE WILL BE PULLED
ACROSS THE REGION IN SOUTHWEST FLOW ALOFT. THIS WILL COMBINE WITH
A MOIST...PRECIPITABLE WATERS AROUND AN INCH...AND UNSTABLE
AIRMASS TO TRIGGER SCATTERED CONVECTION. THE STORMS SHOULD BE WET
AS THE ATMOSPHERIC COLUMN MOISTENS UP.
THE MODELS HAVE DIVERGED FROM PREVIOUS SOLUTIONS FOR WEDNESDAY.
THE CONSENSUS NOW IS TO BUILD A RIDGE UP OVER SOUTHERN MONTANA AS
A DEEP TROUGH APPROACHES THE PACIFIC NORTHWEST COAST. THIS WOULD
PUSH STRONGER FORCING NORTH. WILL HAVE TO WATCH THIS TREND AS MAY
NEED TO LOWER POPS...BUT WILL LEAVE SCATTERED POPS IN FOR NOW AS
HIGH PRECIPITABLE WATER AMOUNTS TEND TO LEAD TO EASY CONVECTIVE
DEVELOPMENT.
THE WESTERN UPPER TROUGH MOVES INLAND ON THURSDAY AND SETS UP
SOUTHWEST FLOW FOR THURSDAY AND FRIDAY. THE FLOW WAS PROGGED TO BE
MOIST AND UNSTABLE AND DIVERGENT...SO THIS LOOKS LIKE THE BEST
PERIOD FOR PRECIPITATION. MAY HAVE TO RAISE POPS FURTHER AS THE
DAY APPROACHES...BUT SCATTERED POPS SHOULD COVER THINGS FOR NOW.
THE ECMWF POINTS TO THE UNSETTLED PATTERN SHUTTING OFF SUNDAY AS
THE STRONG SOUTHERN PLAINS RIDGE BUILDS NORTH. THE GFS HAS THE
SAME IDEA...JUST NOT AS AGGRESSIVE ON BUILDING HEIGHTS.
TEMPERATURES WILL BE HELD BELOW SEASONAL AVERAGES THROUGH THE
ENTIRE EXTENDED PERIOD. THIS DUE TO LOW HEIGHTS...LOW LEVEL EAST
TO NORTHEAST WIND...AND HIGH MOISTURE CONTENT IN THE ATMOSPHERE.
TWH
&&
.AVIATION...
WIDELY SCATTERED SHOWERS AND THUNDERSTORMS WILL MOVE OVER
SOUTHEAST MONTANA THIS MORNING. BRIEF MODERATE RAIN CAN BE
EXPECTED IN THIS ACTIVITY WITH FLYING CONDITIONS REMAINING VFR.
SCATTERED SHOWERS AND THUNDERSTORMS WILL DEVELOP WEST OF KBIL
EARLY THIS AFTERNOON AND SHIFT EAST INTO THE EVENING. WIND GUSTS
TO 35KTS WILL BE POSSIBLE WITH THESE STORMS. BRIEF MVFR FLYING
CONDITIONS WILL BE POSSIBLE IN THE STRONGER CELLS. TWH
&&
.PRELIMINARY POINT TEMP/POPS...
TDY MON TUE WED THU FRI SAT
-------------------------------------------------------
BIL 081 059/080 058/084 059/085 061/082 059/081 059/083
4/T 53/T 32/T 33/T 44/T 43/T 33/T
LVM 084 051/079 049/083 049/084 051/079 050/079 050/080
4/T 53/T 23/T 33/T 44/T 43/T 33/T
HDN 085 059/082 058/085 059/087 059/084 059/083 059/085
5/T 64/T 32/T 33/T 44/T 43/T 33/T
MLS 085 060/082 060/085 060/086 061/084 060/082 061/085
5/T 74/T 33/T 33/T 44/T 43/T 33/T
4BQ 084 056/082 058/085 058/085 058/084 059/081 059/084
5/T 55/T 33/T 33/T 44/T 43/T 33/T
BHK 079 056/078 056/080 056/081 058/080 057/079 057/081
4/T 55/T 33/T 32/T 44/T 43/T 34/T
SHR 084 055/081 055/085 055/085 056/083 055/080 055/083
5/T 64/T 32/T 33/T 34/T 43/T 33/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1247 PM CDT SUN JUL 28 2013
.SHORT TERM...(TODAY AND TONIGHT)...
TODAY...THE NAM...GFS AND RAP MODELS MAINTAIN EXTENSIVE CLOUD COVER
ACROSS WRN AND SCNTL NEB TODAY WHICH SHOULD HOLD MAX TEMPS IN THE
60S TO AROUND 70. SUNSHINE ACROSS THE NERN ZONES WOULD ALLOW HIGHS
IN THE 70S. RAIN CHANCES HAVE DIMINISHED AS THE DISTURBANCE...CURRENTLY
ACROSS KS AND THE CNTL HIGH PLAINS... IS EXPECTED TO MOVE MOSTLY
SOUTH OF THE FCST AREA. THUS POPS HAVE BEEN LOWERED TO ISOLATED
WITH SCATTERED COVERAGE EXPECTED MAINLY SOUTH OF INTERSTATE 80 AND
WEST OF KOGA.
THE ELEVATED MIXED LAYER DRIED OUT TODAY AND THE RESULTING 750MB
CAPE HAS FALLEN OFF WELL BELOW 1000 J/KG WITH K INDICES WELL BELOW
30C. THUS ONLY ISOLATED THUNDERSTORMS ARE EXPECTED TODAY. DEEP
MOISTURE AND WEAK LIFT SUGGEST MOSTLY SHRA ACTIVITY.
TONIGHT...
THE ONGOING DISTURBANCE WILL CONTINUE AFFECTING THE CNTL HIGH PLAINS
AND KS AS IT MOVES VERY SLOWLY EAST THRU THE CNTL PLAINS. THE MODELS
SUGGEST A NRN PUSH OF WARM AIR ADVECTION DRIVEN CONVECTION WHICH
COULD REACH UP INTO LINCOLN AND CUSTER COUNTIES BUT NOT MUCH
FURTHER. THE HRRR...THROUGH 20Z THIS AFTERNOON...IS SUGGESTING A
MORE EAST AND NORTH PUSH OF ISOLATED SHOWERS WHICH COULD PERHAPS SET
THE STAGE FOR A WETTER EVENING. THIS SOLN HAS BEEN SET ASIDE FOR
NOW. LOWS TONIGHT SHOULD FALL INTO THE 40S AND 50S...THE COOLEST
NIGHT SO FAR.
.LONG TERM...(MONDAY THROUGH SATURDAY)...
THE CHANCE FOR SHOWERS AND THUNDERSTORMS CONTINUE MAINLY FOCUSING
IN THE WEST EARLY. THE ZONAL PATTERN ALOFT WILL TRANSITION WITH
HEIGHTS ON THE RISE AS MODELS ARE IN FAIR AGREEMENT THAT A
BLOCKING PATTERN OFF THE WEST COAST MOVES INLAND OVER THE
NORTHWEST COAST. THE FORECAST CHALLENGE WILL BE TEMPERATURES AND
POPS AS SEVERAL SHORTWAVE TROUGHS ARE FORECAST TO MOVE SOUTHEAST
HOWEVER TIMING WILL BE A PROBLEM. FOR NOW LOW POPS CARRIED FORWARD
MONDAY AS THE SEMI STATIONARY FRONT EXTENDING SOUTH ON THE HIGH
PLAINS AND REMAINS A FOCUS FOR SHOWERS AND THUNDERSTORMS THROUGH
WEDNESDAY. BEYOND WEDNESDAY COULD BE AN ACTIVE PATTERN AS THE
BLOCK BREAKS DOWN AND A SERIES OF DISTURBANCES MOVE EAST.
TEMPERATURE GUIDANCE TRENDING UP AND PEAKS THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1247 PM CDT SUN JUL 28 2013
THERE/S TWO CONCERNS GOING FOR THE 18Z TAF PERIOD...BOTH OF WHICH
SEEM TO BE TARGETING THE SOUTHERN TERMINALS MORE SO THAN THE NORTH.
WARM AIR ADVECTION DRIVEN SHOWERS ARE ANTICIPATED TO DEVELOP ONCE
AGAIN THIS EVENING/OVERNIGHT ACROSS PORTIONS OF SOUTHWEST AND
SOUTHERN NEBRASKA...POSSIBLY SPREADING NORTH ACROSS KLBF. FOR
THIS...WILL INTRODUCE A PROB30 GROUP FOR -SHRA FROM 07-11Z.
GUIDANCE IS SOMEWHAT SPLIT WITH THE TIMING AND LOCATION...SO UPDATES
MAY BE NEEDED. THE PATTERN IS ALSO FAVORABLE FOR ADVECTION DRIVEN
FOG...ONCE AGAIN WITH HIGHEST PROBABILITY OCCURRING ALONG OUR
SOUTHERN TERMINALS. WITH MUCH LESS CONFIDENCE...WILL LOWER THE
PREVAILING VISIBILITY TO 3SM AND OVC010 AFTER 12Z AT KLBF...WITH THE
ANTICIPATION THAT ANY CLEARING SHOULD ALLOW FOR RAPID DETERIORATION
OF FLIGHT CEILINGS/VISIBILITY.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...KECK
AVIATION...JACOBS
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
614 AM CDT SUN JUL 28 2013
.SHORT TERM...(TODAY AND TONIGHT)...
TODAY...THE NAM...GFS AND RAP MODELS MAINTAIN EXTENSIVE CLOUD COVER
ACROSS WRN AND SCNTL NEB TODAY WHICH SHOULD HOLD MAX TEMPS IN THE
60S TO AROUND 70. SUNSHINE ACROSS THE NERN ZONES WOULD ALLOW HIGHS
IN THE 70S. RAIN CHANCES HAVE DIMINISHED AS THE DISTURBANCE...CURRENTLY
ACROSS KS AND THE CNTL HIGH PLAINS... IS EXPECTED TO MOVE MOSTLY
SOUTH OF THE FCST AREA. THUS POPS HAVE BEEN LOWERED TO ISOLATED
WITH SCATTERED COVERAGE EXPECTED MAINLY SOUTH OF INTERSTATE 80 AND
WEST OF KOGA.
THE ELEVATED MIXED LAYER DRIED OUT TODAY AND THE RESULTING 750MB
CAPE HAS FALLEN OFF WELL BELOW 1000 J/KG WITH K INDICES WELL BELOW
30C. THUS ONLY ISOLATED THUNDERSTORMS ARE EXPECTED TODAY. DEEP
MOISTURE AND WEAK LIFT SUGGEST MOSTLY SHRA ACTIVITY.
TONIGHT...
THE ONGOING DISTURBANCE WILL CONTINUE AFFECTING THE CNTL HIGH PLAINS
AND KS AS IT MOVES VERY SLOWLY EAST THRU THE CNTL PLAINS. THE MODELS
SUGGEST A NRN PUSH OF WARM AIR ADVECTION DRIVEN CONVECTION WHICH
COULD REACH UP INTO LINCOLN AND CUSTER COUNTIES BUT NOT MUCH
FURTHER. THE HRRR...THROUGH 20Z THIS AFTERNOON...IS SUGGESTING A
MORE EAST AND NORTH PUSH OF ISOLATED SHOWERS WHICH COULD PERHAPS SET
THE STAGE FOR A WETTER EVENING. THIS SOLN HAS BEEN SET ASIDE FOR
NOW. LOWS TONIGHT SHOULD FALL INTO THE 40S AND 50S...THE COOLEST
NIGHT SO FAR.
.LONG TERM...(MONDAY THROUGH SATURDAY)...
THE CHANCE FOR SHOWERS AND THUNDERSTORMS CONTINUE MAINLY FOCUSING
IN THE WEST EARLY. THE ZONAL PATTERN ALOFT WILL TRANSITION WITH
HEIGHTS ON THE RISE AS MODELS ARE IN FAIR AGREEMENT THAT A
BLOCKING PATTERN OFF THE WEST COAST MOVES INLAND OVER THE
NORTHWEST COAST. THE FORECAST CHALLENGE WILL BE TEMPERATURES AND
POPS AS SEVERAL SHORTWAVE TROUGHS ARE FORECAST TO MOVE SOUTHEAST
HOWEVER TIMING WILL BE A PROBLEM. FOR NOW LOW POPS CARRIED FORWARD
MONDAY AS THE SEMI STATIONARY FRONT EXTENDING SOUTH ON THE HIGH
PLAINS AND REMAINS A FOCUS FOR SHOWERS AND THUNDERSTORMS THROUGH
WEDNESDAY. BEYOND WEDNESDAY COULD BE AN ACTIVE PATTERN AS THE
BLOCK BREAKS DOWN AND A SERIES OF DISTURBANCES MOVE EAST.
TEMPERATURE GUIDANCE TRENDING UP AND PEAKS THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 613 AM CDT SUN JUL 28 2013
LOCAL MVFR CIGS ACROSS SWRN NEB SHOULD LIFT TO VFR 16Z-18Z.
ISOLATED SHOWERS AND THUNDERSTORMS ARE POSSIBLE MAINLY SOUTH AND
WEST ALONG I-80 OTHERWISE VFR SHOULD PREVAIL.
TONIGHT...CIGS COULD LOWER TO MVFR AGAIN ACROSS WRN/SWRN NEB
INCLUDING KLBF. SOUTH WINDS WILL INCREASE AND PULL MOISTURE UP THE
HIGH PLAINS. THE NAM MODEL IS SUGGESTING IFR CIGS WHILE THE GFS
SHOWS MVFR. FOR NOW ITS BEST TO FOLLOW THE GFS AND FCST MVFR CIGS
AS THE NAM IS KNOWN TO COME IN TOO LOW.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...KECK
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
404 AM CDT SUN JUL 28 2013
.SHORT TERM...(TODAY AND TONIGHT)...
TODAY...THE NAM...GFS AND RAP MODELS MAINTAIN EXTENSIVE CLOUD COVER
ACROSS WRN AND SCNTL NEB TODAY WHICH SHOULD HOLD MAX TEMPS IN THE
60S TO AROUND 70. SUNSHINE ACROSS THE NERN ZONES WOULD ALLOW HIGHS
IN THE 70S. RAIN CHANCES HAVE DIMINISHED AS THE DISTURBANCE...CURRENTLY
ACROSS KS AND THE CNTL HIGH PLAINS... IS EXPECTED TO MOVE MOSTLY
SOUTH OF THE FCST AREA. THUS POPS HAVE BEEN LOWERED TO ISOLATED
WITH SCATTERED COVERAGE EXPECTED MAINLY SOUTH OF INTERSTATE 80 AND
WEST OF KOGA.
THE ELEVATED MIXED LAYER DRIED OUT TODAY AND THE RESULTING 750MB
CAPE HAS FALLEN OFF WELL BELOW 1000 J/KG WITH K INDICES WELL BELOW
30C. THUS ONLY ISOLATED THUNDERSTORMS ARE EXPECTED TODAY. DEEP
MOISTURE AND WEAK LIFT SUGGEST MOSTLY SHRA ACTIVITY.
TONIGHT...
THE ONGOING DISTURBANCE WILL CONTINUE AFFECTING THE CNTL HIGH PLAINS
AND KS AS IT MOVES VERY SLOWLY EAST THRU THE CNTL PLAINS. THE MODELS
SUGGEST A NRN PUSH OF WARM AIR ADVECTION DRIVEN CONVECTION WHICH
COULD REACH UP INTO LINCOLN AND CUSTER COUNTIES BUT NOT MUCH
FURTHER. THE HRRR...THROUGH 20Z THIS AFTERNOON...IS SUGGESTING A
MORE EAST AND NORTH PUSH OF ISOLATED SHOWERS WHICH COULD PERHAPS SET
THE STAGE FOR A WETTER EVENING. THIS SOLN HAS BEEN SET ASIDE FOR
NOW. LOWS TONIGHT SHOULD FALL INTO THE 40S AND 50S...THE COOLEST
NIGHT SO FAR.
.LONG TERM...(MONDAY THROUGH SATURDAY)...
THE CHANCE FOR SHOWERS AND THUNDERSTORMS CONTINUE MAINLY FOCUSING
IN THE WEST EARLY. THE ZONAL PATTERN ALOFT WILL TRANSITION WITH
HEIGHTS ON THE RISE AS MODELS ARE IN FAIR AGREEMENT THAT A
BLOCKING PATTERN OFF THE WEST COAST MOVES INLAND OVER THE
NORTHWEST COAST. THE FORECAST CHALLENGE WILL BE TEMPERATURES AND
POPS AS SEVERAL SHORTWAVE TROUGHS ARE FORECAST TO MOVE SOUTHEAST
HOWEVER TIMING WILL BE A PROBLEM. FOR NOW LOW POPS CARRIED FORWARD
MONDAY AS THE SEMI STATIONARY FRONT EXTENDING SOUTH ON THE HIGH
PLAINS AND REMAINS A FOCUS FOR SHOWERS AND THUNDERSTORMS THROUGH
WEDNESDAY. BEYOND WEDNESDAY COULD BE AN ACTIVE PATTERN AS THE
BLOCK BREAKS DOWN AND A SERIES OF DISTURBANCES MOVE EAST.
TEMPERATURE GUIDANCE TRENDING UP AND PEAKS THURSDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1239 AM CDT SUN JUL 28 2013
THE SHOWERS/THUNDERSTORMS ALONG A WEAK FRONT SPREADING INTO
SOUTHWEST AND WESTERN NEBRASKA FROM WYOMING...COLORADO AND NORTHWEST
KANSAS WILL REACH AN OGA-LXN LINE BY 09Z AND COULD REACH IEN-MHN-LBF
BY 15Z. THE SHOWERS/THUNDERSTORMS MAY SPREAD INTO CENTRAL AND NORTH
CENTRAL NEBRASKA BY LATE AFTERNOON. THERE ARE SIGNIFICANT
DIFFERENCES WITH THE PROBABILITY OF RAIN IN THE STATISTICAL OUTPUT
FROM THE EVENING MODEL RUN. FOR LBF...THE PROBABILITY INCREASES
SIGNIFICANTLY BY LATE AFTERNOON TO EARLY EVENING. THE TWO AVAILABLE
STATISTICAL BULLETINS DIFFER WIDELY IN THE ACTUAL PROBABILITY. WITH
MARGINAL INSTABILITY ONLY...IT IS REASONABLE TO LEAVE THUNDER OUT
ALTOGETHER...BUT IT IS NOT UNREASONABLE TO INCLUDE SHOWERS IN THE
LBF TAF. AFTER 15Z WE CAN EXPECT WIDESPREAD CEILINGS AT OR BELOW
3000 FEET AND VISIBILITY COULD BE LESS THAN 3SM AT TIMES IN THE
RAIN. CONFIDENCE IS HIGH THAT CEILINGS WILL BE AT OR BELOW 3000
FEET. FOR RAIN...THE CONFIDENCE IS NOT AS HIGH.
.LBF WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...KECK
AVIATION....CDC
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1244 AM CDT SUN JUL 28 2013
.SHORT TERM...TONIGHT THROUGH SUNDAY AFTERNOON.
ISSUED AT 345 PM CDT SAT JUL 27 2013
FORECAST CONCERNS IN THE SHORT TERM INCLUDE TEMPS WELL BELOW
NORMAL FOR THIS TIME OF YEAR ALONG WITH SMALL PRECIP CHANCES.
CURRENT UPPER AIR...WIND PROFILER NETWORK AND WATER VAPOR SATELLITE
IMAGERY SHOWING AN UPPER LOW OVER THE GREAT LAKES THAT IS EXPECTED
TO WOBBLE IN PLACE THE NEXT 24 HOURS. ANOTHER LOW PRESSURE REGION
WAS OVER EASTERN BRITISH COLUMBIA MOVING INTO ALBERTA...WHILE
FURTHER SOUTH ANOTHER LOW PRESSURE CIRCULATION COULD BE SEEN A
COUPLE HUNDRED MILES OFF THE CENTRAL CALIFORNIA COAST. A WEAK RIDGE
OF HIGH PRESSURE WAS SITUATED OVER THE ROCKIES WITH VARIOUS MINOR
SHORT WAVES ROTATING THROUGH THIS RIDGE...INCLUDING ONE THAT
TRIGGERED ISOLATED TSTMS THIS MORNING. AT THE SURFACE A RIDGE OF
HIGH PRESSURE EXTENDS FROM THE NORTHERN INTO THE CENTRAL PLAINS. LOW
PRESSURE AND AN ASSOCIATED BOUNDARY WAS NOTED OVER THE LEE OF THE
ROCKIES AND THEN EAST ACROSS SOUTHERN OKLAHOMA AND ARKANSAS. CLOSER
TO HOME...WINDS ARE LIGHT DUE TO THE WEAK PRESSURE GRADIENT.
DEWPOINTS WERE VERY COMFORTABLE FOR THIS TIME OF YEAR RANGING FROM
THE MID 40S ACROSS THE NORTHERN CWA TO THE LOWER/MID 50S SOUTH.
FOR TONIGHT...IT APPEARS THE BEST CHANCE FOR RAIN WILL HINGE ON THE
DEGREE OF WARM ADVECTION THAT SETS UP. BOTH THE NAM AND RAP MODELS
ARE IN AGREEMENT IN DEVELOPING A DECENT LOW LEVEL JET AFTER 02Z IN
THE SOUTHERN PART OF THE CWA. THE 310K DEGREE ISENTROPIC PLAN VIEW
PLOT SHOWS THIS NICELY WITH A 30-40 KT JET RIDING OVER THE SURFACE
BOUNDARY AND INTO OUR AREA. MIXING RATIOS HERE ARE AROUND 9-10 G/KG
WITH BEST LIFT IN THE SOUTHWEST. REAL QUESTION THEN BECOME HOW FAR
INTO THE CWA TO EXTEND THE RAIN CHANCES AS WARM ADVECTION NIL OVER
THE NORTHEAST THIRD OF THE CWA ACCORDING TO THE NAM. ANY TSTM
ACTIVITY THAT DOES POP UP OVERNIGHT SHOULD REMAIN BELOW SEVERE
LIMITS AS MU CAPE ONLY A COUPLE HUNDRED J/KG AT BEST EVEN THOUGH
DEEP LAYER SHEAR IS RESPECTABLE. DEWPOINTS TO REMAIN LOW AND GIVEN
THE COOLER AIR MASS...OVERNIGHT LOWS SHOULD BE AROUND 15 DEGREES
BELOW AVERAGE FOR THIS TIME OF YEAR WHICH IS 65 IN KGRI.
PRECIPITATION CHANCES TO CONTINUE DURING THE DAYTIME ON SUNDAY AS
MODELS IN GOOD AGREEMENT IN SLIDING SHORT WAVE TROUGH FROM THE
DESERT SW INTO OUR NECK OF THE WOODS. BEST CHANCES STILL APPEAR TO
BE IN OUR SOUTHERN CWA...ACTUALLY SOUTH OF THERE...CLOSER TO THE
FRONT. ONCE AGAIN...MU CAPE VALUES REMAIN LOW DUE TO THE COOLER LOW
LEVEL TEMPERATURES AND LOWER DEW POINTS...SO SEVERE CHANCES ARE
MINIMAL. HIGHS ON SUNDAY ARE EXPECTED TO REMAIN BELOW NORMAL WITH
COOLER AIR MASS. KGRI AVERAGE HIGH IS 87 AND FORECAST HIGH WILL BE
ABOUT 15 DEGREES BELOW THAT.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 340 PM CDT SAT JUL 27 2013 MAIN FORECAST CONCERNS WILL
BE CHANCES FOR THUNDERSTORMS AND TEMPERATURES.
GENERALLY NORTHWEST FLOW WILL CONTINUE THROUGH THE PERIOD. THERE ARE
SEVERAL UPPER LEVEL WAVES THAT MOVE THROUGH THE AREA AND BRING
CHANCES FOR PRECIPITATION TO THE AREA. IT CERTAINLY WILL NOT RAIN
ALL THE TIME OR IN ALL LOCATIONS.
THE STRONGEST OF THE UPPER LEVEL WAVES WILL BE MOVING THROUGH THE
AREA SUNDAY NIGHT AND MONDAY. THIS WILL BE THE BEST CHANCE FOR
PRECIPITATION. SUNDAY NIGHT THE UPPER WAVE WILL CONTINUE TO PUSH
THROUGH THE AREA. PRECIPITATION SPREADS A LITTLE TO THE NORTH DURING
THE NIGHT. THIS WILL BE THE BEST CHANCE FOR PRECIPITATION ESPECIALLY
IN THE SOUTH. THE UPPER WAVE WILL START TO MOVE OUT OF THE AREA ON
MONDAY BUT THERE STILL REMAINS A CHANCE FOR SOME SHOWERS AND
THUNDERSTORMS ACROSS THE AREA DURING THE DAY. THE BEST CHANCE WILL
BE IN THE SOUTHEAST PART OF THE AREA.
MONDAY NIGHT BRINGS THE FIRST BREAK...BUT ONLY FOR PART OF THE
FORECAST AREA. A SURFACE HIGH TRIES TO BUILD INTO THE AREA BUT CAN
ONLY BRING A BREAK TO PART OF THE AREA WITH ISOLATED PRECIPITATION
IN THE SOUTHEAST.
FOR THE PERIOD TUESDAY THROUGH WEDNESDAY NIGHT. A SERIES OF WEAK
UPPER LEVEL WAVES WILL MOVE THROUGH THE AREA. THERE ARE CHANCES FOR
THUNDERSTORMS FOR PORTIONS OF THE AREA MAINLY IN THE WEST AND NORTH.
THE CHANCES ARE FAIRLY SMALL AND MODELS HAVE SLIGHTLY DIFFERENT
TIMING OF THE WAVES AS THEY MOVE THROUGH THE AREA.
THURSDAY THROUGH FRIDAY NIGHT THE CHANCES FOR THUNDERSTORMS WILL BE
ACROSS THE ENTIRE AREA. THESE TOO ARE FAIRLY SMALL CHANCES AND IT IS
POSSIBLE THAT THERE MAY NOT BE PRECIPITATION AT SOME LOCATIONS.
A SURFACE HIGH PRESSURE SYSTEM TRIES TO SETTLE INTO THE FORECAST
AREA AGAIN ON SATURDAY AND MOST OF THE AREA WILL BE DRY. THERE IS A
SLIGHT CHANCE IN THE FAR SOUTH.
TEMPERATURES WILL REMAIN ON THE COOL SIDE FOR MONDAY...BUT RETURN TO
MORE SEASONABLE TEMPERATURES FOR THE REST OF THE WEEK WHEN
TEMPERATURES ARE EXPECTED TO BE AT OR A LITTLE BELOW NORMAL FOR THIS
TIME OF YEAR.
&&
.AVIATION...(FOR THE 06Z KGRI TAF THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1240 AM CDT SUN JUL 28 2013
VFR CONDITIONS ARE EXPECTED TO PREVAIL AT KGRI FOR THE NEXT 24
HOURS. CALM WINDS EARLY THIS MORNING WILL EVENTUALLY INCREASE OUT
OF THE SOUTHEAST NEAR 10 KTS BY DAYBREAK...WITH CEILINGS EVENTUALLY
LOWERING TO NEAR 10KFT. MAY SEE A VCSH OR VCTS AROUND THE TERMINAL
DURING THE EARLY MORNING THROUGH AFTERNOON HOURS AS SHOWERS NORTH
OF A WARM FRONT APPROACH KGRI...BUT WITH BULK OF ACTIVITY EXPECTED
TO REMAIN SOUTH OF INTERSTATE 80...DID NOT MENTION A TEMPO OR
PREVAILING WX GROUP AT THIS TIME. OTHERWISE...CEILINGS WILL
CONTINUE TO LOWER AFTER SUNSET TONIGHT...AS ADDITIONAL MOISTURE
WORKS ITS WAY NORTHWARD...BRINGING A BETTER CHANCE FOR SHOWERS AND
THUNDERSTORMS NEAR THE TERMINAL LATE SUNDAY NIGHT THROUGH MONDAY
MORNING.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...EWALD
LONG TERM...JCB
AVIATION...SAR
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
1157 AM MDT SUN JUL 28 2013
.AVIATION...
18Z TAF CYCLE
VFR CONDITIONS LIKELY TO PERSIST THROUGH THE NEXT 24 HRS EXCEPT
FOR SHRA AND TSRA. STRONGER TSRA WILL BE ABLE TO PRODUCE BRIEF
MVFR CIGS AND VSBY WITH THE MOST INTENSE PRODUCING LOCALIZED IFR
CIGS AND VSBY AND MT OBSCURATIONS. PEAK WIND GUSTS WITH THE
STRONGEST ACTIVITY COULD REACH 40 TO 50 KT. GREATEST TSRA COVERAGE
ACROSS CNTRL MOUNTAIN CHAIN WITH NUMEROUS CELLS. ISOLATED TO
SCATTERED COVERAGE ELSEWHERE. FOR THE TAFS...CARRIED A TEMPO GROUP
FOR GUSTY STORMS THIS PM/EARLY EVE FOR ALL EXCEPT KTCC AND KROW.
ONLY VCTS THIS EVE AT KTCC AND VCSH KROW. THE ACTIVITY WILL BEGIN
TO DIMINISH AFTER 01Z WITH MOST OF THE CONVECTION OVER BY 06Z. 40
&&
.PREV DISCUSSION...724 AM MDT SUN JUL 28 2013...
AFTER REVIEWING THE 12Z KABQ SOUNDING AND VARIOUS OTHER MODEL
PARAMETERS HAVE DECIDED TO ISSUE A FLASH FLOOD WATCH TODAY FOR
BASICALLY THE WESTERN HALF OF NM. SURFACE DEWPOINT VALUES ARE
ABOUT AS HIGH AS THEY EVER GET AROUND CENTRAL AND WESTERN NM. THE
ENTIRE ATMOSPHERIC COLUMN IS ESSENTIALLY SATURATED AND OUR PWAT
VALUE OF 1.27 THIS MORNING IS WELL WITHIN FLASH FLOOD TERRITORY.
INSTABILITY IS ABUNDANT AND OUR CONVECTIVE TEMP IS QUITE LOW SO
CONVECTION SHOULD FIRE EARLY THEN SPREAD SLOWLY EAST NEAR 10MPH.
A WELL DEFINED GRADIENT OF DRIER AIR AND A COUPLE ASSCD SHORTWAVE
TROUGHS WILL BE WORKING INTO THE REGION FROM THE WEST BY LATE DAY.
PREVIOUS RESEARCH STUDIES HAVE SHOWN THIS IS A PARTICULARLY IDEAL
SET UP FOR FLASH FLOOD EVENTS ACROSS NM. BASED ON THE 06Z NAM AND
THE 10Z HRRR NOT ALL AREAS WILL BE UNDER THE GUN FOR FLOODING IN
THE WATCH AREA HOWEVER IT IS TOO DIFFICULT TO PINPOINT FAVORED
LOCALES SO THIS WATCH IS LARGE. GUYER
.PREV DISCUSSION...337 AM MDT SUN JUL 28 2013...
...LOCALLY HEAVY RAINFALL ON TAP FOR NEW MEXICO ONCE AGAIN TODAY...
SEVERAL VERY INTERESTING FEATURES AT PLAY TODAY WILL DEFINITELY MAKE
FOR A MORE ACTIVE DAY THAN SATURDAY. THE LATEST WATER VAPOR AND CIRA
BLENDED PW LOOPS SHOW A DEEPLY SATURATED ATMOSPHERE ENTRENCHED OVER
AZ AND NM. THE UPPER RIDGE CENTROID IS CLEARLY CENTERED OVER EL PASO.
A WELL DEFINED VORT MAX OVER SOUTHEASTERN AZ IS SLIDING NE ALONG THE
WESTERN PERIPHERY OF THE UPPER RIDGE. MEANWHILE AN ENTIRELY SEPARATE
AREA OF UPPER LEVEL INSTABILITY ASSOCIATED WITH AN UPPER SHORTWAVE
TROUGH STRETCHES FROM WESTERN AZ ENE INTO THE FOUR CORNERS REGION
AND SOUTHERN CO. SHOWERS AND STORMS HAVE BEEN ONGOING ACROSS BOTH
OF THESE AREAS ALL NIGHT.
THE 06Z AND LATEST HRRR HANDLE BOTH FEATURES VERY WELL. GUIDANCE ALSO
FALLS IN LINE WITH LATEST HPC QPF PROBABILITIES SO HAVE NUDGED POPS
UP QUITE A BIT TODAY. CONVECTIVE TEMPS INDICATED BY THE 06Z NAM OVER
THE REGION ARE VERY LOW SO CONFIDENCE IS HIGH THAT CONVECTION WILL
FIRE UP EARLY OVER WESTERN NM AND SHIFT EAST INTO THE RIO GRANDE
VALLEY BY EARLY AFTERNOON. THE VORT MAX LOOKS TO CROSS THE SOUTH
CENTRAL MTS BY MID AFTERNOON AND INCREASE THE POTENTIAL FOR FLASH
FLOODING OVER THE BURN SCARS WITHIN LINCOLN COUNTY. THE NORTH WILL
ALSO FIRE UP EARLY BUT CONTINUE LATER INTO THE EVENING AS STRONGER
UPPER DYNAMICS PUSH SLOWLY SOUTHEAST OVER THE AREA. SOME TRAINING
IS POSSIBLE ACROSS THIS AREA WHERE LOCALLY HEAVY RAINFALL IS LIKELY.
THE FARMINGTON AREA REALLY NEEDS THE RAIN AND TODAY SHOULD BE THE DAY.
THE DRYING TREND WILL COMMENCE MONDAY AND TUESDAY AS DRIER AIR FILTERS
INTO THE REGION FROM THE GREAT BASIN. THE GREATEST POTENTIAL FOR STORMS
WILL BE OVER THE NORTHERN HIGH TERRAIN WHERE MOISTURE RECYCLING WILL
BE MOST EFFICIENT. THE NE PLAINS WILL ALSO HAVE ELEVATED POPS AS A
WEAK BACK DOOR FRONTAL BOUNDARY SHIFTS SW INTO THE AREA. TUESDAY MAY
BE THE DRIEST DAY IN QUITE SOME TIME WITH MODEL GUIDANCE INDICATING
DEWPOINT VALUES RANGING FROM THE UPPER 20S ACROSS THE FAR NW PLATEAU
TO THE 40S OVER THE PLAINS.
THE UPPER HIGH WILL BUILD NORTHWEST OVER THE STATE AND STRENGTHEN TO
NEAR 596DM BY WEDNESDAY AND THURSDAY. THIS WILL INCREASE TEMPS BACK
SLIGHTLY ABOVE NORMAL AND REALLY FOCUS MOISTURE RECYCLING PROCESSES
IN AND IMMEDIATELY NEARBY THE HIGH TERRAIN WITH WEAK STEERING FLOW.
FLASH FLOOD THREAT MAY INCREASE ONCE AGAIN FOR BURN SCAR AREAS IN
THIS PATTERN. A STATIONARY PATTERN IS INDICATED BY THE GFS AND ECMWF
SOLUTION THURSDAY THROUGH NEXT WEEK WITH AN UPPER HIGH OVER WEST TX/
EASTERN NM AND A MOISTURE SURGE SLIDING NORTH OVER WESTERN NM. THIS
WILL BE A MUCH NEEDED WINDOW FOR PRECIP ACROSS THE GALLUP/FARMINGTON
AREA WHICH HAS BEEN RELATIVELY PARCHED THIS SUMMER. GUYER
&&
.FIRE WEATHER...
WX PATTERN CHANGE BEGAN SAT AS HIGH PRESSURE ALOFT SHIFTED OVER TO
FAR N MEXICO WHICH IN TURN EASED OUR STORM STEERING FLOW FROM A
GENERALLY N TO S DIRECTION TO A MORE W TO E DIRECTION. THIS
WILL...MAINLY AFTER TODAY...BRING IN SIGNIFICANTLY DRIER AIR ALOFT
WHICH WILL OF COURSE SIGNIFICANTLY CUT BACK SFC DEWPOINTS AND ALSO
CONVECTION. THIS STORM DOWNTURN WILL LAST AT LEAST INTO TUE AND MORE
THAN LIKELY WED AS WELL...IF NOT LONGER.
WHILE A LITTLE DRIER AIR MAY BEGIN TO PUSH INTO WESTERN NEW MEXICO
LATER TODAY...THERE SHOULD BE SUFFICIENT AMOUNTS REMAINING TO
TRIGGER A DECENT CROP OF SHOWERS AND STORMS. IT APPEARS THAT BEST
CHANCES FOR SUBSTANTIAL RAINFALL TODAY WILL BE NORTHERN MTNS AND
PERHAPS A LITTLE LESSER DEGREE THE SANDIAS SOUTHWARD TO THE
SACRAMENTOS AS WELL AS THE NE PLAINS WHERE A WEAK SFC BOUNDARY MAY
LINGER. WESTERLY WINDS WILL LIKELY BECOME SOMEWHAT GUSTY ALONG THE
CONTDVD AND ACROSS THE CENTRAL HIGHLANDS/WESTERN EAST CENTRAL PLAINS
THIS AFTN BUT LOW LEVEL MOISTURE IS NOT EXPECTED TO BE
SCOURED OUT SO MUCH THAT MIN RH VALUES FALL BELOW 15 PERCENT.
VENTILATION WILL IMPROVE SIGNIFICANTLY THIS AFTN.
DRYING TREND ACCELERATES MON WITH ONLY ISOLD CONVECTION IN THE
FORECAST FOR WESTERN AND SOUTHERN HIGH TERRAIN. WETTING RAIN STILL
IN CHANCE CATEGORY FROM THE SANGRE DE CRISTO MTS EASTWARD TO THE TX
BORDER...THOUGH NEARLY ALL AREAS OF N AND CENTRAL NM TO SEE FURTHER
REDUCTIONS IN WETTING RAIN COVERAGE AND POTENTIAL TUE AS DRYING
TREND MAY REACH ITS PEAK. VENTILATION WILL BE VERY GOOD TO EXCELLENT
FOR MOST OF THE FORECAST AREA. BOTH MIN AND MAX RH VALUES TREND
DOWNWARD AFFECTING OVERNIGHT RECOVERIES MON AND TUE NIGHT...ESPEC IN
THE NORTHWEST PLATEAU AND PORTIONS OF THE MIDDLE RIO GRANDE VALLEY.
STILL FAIRLY GOOD MODEL AGREEMENT ON A TREND OF MOISTURE RETURNING
DURING THE LATTER HALF NEXT WEEK AS THE UPPER HIGH CENTER SHIFTS
NORTHWARD OUT OF OLD MEXICO. THE FOCUS FOR WETTING RAIN WOULD APPEAR
TO BE THE NORTHERN AND WESTERN PORTIONS OF THE FCST AREA...BEARING A
LITTLE MORE RESEMBLANCE TO A TRADITIONAL MONSOON PATTERN...THOUGH
NOT AN ESPECIALLY STRONG ONE JUST YET. 43
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 10 PM MDT THIS EVENING FOR THE FOLLOWING
ZONES...NMZ501>529.
&&
$$
40
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
724 AM MDT SUN JUL 28 2013
.UPDATE...
AFTER REVIEWING THE 12Z KABQ SOUNDING AND VARIOUS OTHER MODEL
PARAMETERS HAVE DECIDED TO ISSUE A FLASH FLOOD WATCH TODAY FOR
BASICALLY THE WESTERN HALF OF NM. SURFACE DEWPOINT VALUES ARE
ABOUT AS HIGH AS THEY EVER GET AROUND CENTRAL AND WESTERN NM. THE
ENTIRE ATMOSPHERIC COLUMN IS ESSENTIALLY SATURATED AND OUR PWAT
VALUE OF 1.27 THIS MORNING IS WELL WITHIN FLASH FLOOD TERRITORY.
INSTABILITY IS ABUNDANT AND OUR CONVECTIVE TEMP IS QUITE LOW SO
CONVECTION SHOULD FIRE EARLY THEN SPREAD SLOWLY EAST NEAR 10MPH.
A WELL DEFINED GRADIENT OF DRIER AIR AND A COUPLE ASSCD SHORTWAVE
TROUGHS WILL BE WORKING INTO THE REGION FROM THE WEST BY LATE DAY.
PREVIOUS RESEARCH STUDIES HAVE SHOWN THIS IS A PARTICULARLY IDEAL
SET UP FOR FLASH FLOOD EVENTS ACROSS NM. BASED ON THE 06Z NAM AND
THE 10Z HRRR NOT ALL AREAS WILL BE UNDER THE GUN FOR FLOODING IN
THE WATCH AREA HOWEVER IT IS TOO DIFFICULT TO PINPOINT FAVORED
LOCALES SO THIS WATCH IS LARGE.
GUYER
&&
.PREV DISCUSSION...555 AM MDT SUN JUL 28 2013...
.AVIATION...
12Z TAF CYCLE
VFR CONDITIONS LIKELY TO PERSIST THROUGH THE NEXT 24HRS OUTSIDE
OF SHRA AND TSRA. STRONGER TSRA WILL BE ABLE TO PRODUCE BRIEF MVFR
CIGS AND VSBY WITH THE MOST INTENSE PRODUCING VERY LOCALIZED IFR
CIGS AND VSBY. PEAK WIND GUSTS WITH THE STRONGEST ACTIVITY COULD
REACH 40 TO 55 KT. IN ADDITION...AT LEAST PARTIAL MT OBSCURATIONS
TO BE EXPECTED WITH THE MORE INTENSE ACTIVITY. GREATEST TSRA
COVERAGE MOST LIKELY TO BE ACROSS N MTS AND PERHAPS THE NE
HIGHLANDS AND PLAINS. ISOLATED TO LOCALLY SCATTERED COVERAGE
ELSEWHERE. THE ACTIVITY WILL DIMINISH LATER THIS EVE AND
OVERNIGHT.
43
.PREV DISCUSSION...337 AM MDT SUN JUL 28 2013...
...LOCALLY HEAVY RAINFALL ON TAP FOR NEW MEXICO ONCE AGAIN TODAY...
SEVERAL VERY INTERESTING FEATURES AT PLAY TODAY WILL DEFINITELY MAKE
FOR A MORE ACTIVE DAY THAN SATURDAY. THE LATEST WATER VAPOR AND CIRA
BLENDED PW LOOPS SHOW A DEEPLY SATURATED ATMOSPHERE ENTRENCHED OVER
AZ AND NM. THE UPPER RIDGE CENTROID IS CLEARLY CENTERED OVER EL PASO.
A WELL DEFINED VORT MAX OVER SOUTHEASTERN AZ IS SLIDING NE ALONG THE
WESTERN PERIPHERY OF THE UPPER RIDGE. MEANWHILE AN ENTIRELY SEPARATE
AREA OF UPPER LEVEL INSTABILITY ASSOCIATED WITH AN UPPER SHORTWAVE
TROUGH STRETCHES FROM WESTERN AZ ENE INTO THE FOUR CORNERS REGION
AND SOUTHERN CO. SHOWERS AND STORMS HAVE BEEN ONGOING ACROSS BOTH
OF THESE AREAS ALL NIGHT.
THE 06Z AND LATEST HRRR HANDLE BOTH FEATURES VERY WELL. GUIDANCE ALSO
FALLS IN LINE WITH LATEST HPC QPF PROBABILITIES SO HAVE NUDGED POPS
UP QUITE A BIT TODAY. CONVECTIVE TEMPS INDICATED BY THE 06Z NAM OVER
THE REGION ARE VERY LOW SO CONFIDENCE IS HIGH THAT CONVECTION WILL
FIRE UP EARLY OVER WESTERN NM AND SHIFT EAST INTO THE RIO GRANDE
VALLEY BY EARLY AFTERNOON. THE VORT MAX LOOKS TO CROSS THE SOUTH
CENTRAL MTS BY MID AFTERNOON AND INCREASE THE POTENTIAL FOR FLASH
FLOODING OVER THE BURN SCARS WITHIN LINCOLN COUNTY. THE NORTH WILL
ALSO FIRE UP EARLY BUT CONTINUE LATER INTO THE EVENING AS STRONGER
UPPER DYNAMICS PUSH SLOWLY SOUTHEAST OVER THE AREA. SOME TRAINING
IS POSSIBLE ACROSS THIS AREA WHERE LOCALLY HEAVY RAINFALL IS LIKELY.
THE FARMINGTON AREA REALLY NEEDS THE RAIN AND TODAY SHOULD BE THE DAY.
THE DRYING TREND WILL COMMENCE MONDAY AND TUESDAY AS DRIER AIR FILTERS
INTO THE REGION FROM THE GREAT BASIN. THE GREATEST POTENTIAL FOR STORMS
WILL BE OVER THE NORTHERN HIGH TERRAIN WHERE MOISTURE RECYCLING WILL
BE MOST EFFICIENT. THE NE PLAINS WILL ALSO HAVE ELEVATED POPS AS A
WEAK BACK DOOR FRONTAL BOUNDARY SHIFTS SW INTO THE AREA. TUESDAY MAY
BE THE DRIEST DAY IN QUITE SOME TIME WITH MODEL GUIDANCE INDICATING
DEWPOINT VALUES RANGING FROM THE UPPER 20S ACROSS THE FAR NW PLATEAU
TO THE 40S OVER THE PLAINS.
THE UPPER HIGH WILL BUILD NORTHWEST OVER THE STATE AND STRENGTHEN TO
NEAR 596DM BY WEDNESDAY AND THURSDAY. THIS WILL INCREASE TEMPS BACK
SLIGHTLY ABOVE NORMAL AND REALLY FOCUS MOISTURE RECYCLING PROCESSES
IN AND IMMEDIATELY NEARBY THE HIGH TERRAIN WITH WEAK STEERING FLOW.
FLASH FLOOD THREAT MAY INCREASE ONCE AGAIN FOR BURN SCAR AREAS IN
THIS PATTERN. A STATIONARY PATTERN IS INDICATED BY THE GFS AND ECMWF
SOLUTION THURSDAY THROUGH NEXT WEEK WITH AN UPPER HIGH OVER WEST TX/
EASTERN NM AND A MOISTURE SURGE SLIDING NORTH OVER WESTERN NM. THIS
WILL BE A MUCH NEEDED WINDOW FOR PRECIP ACROSS THE GALLUP/FARMINGTON
AREA WHICH HAS BEEN RELATIVELY PARCHED THIS SUMMER.
GUYER
.FIRE WEATHER...
WX PATTERN CHANGE BEGAN SAT AS HIGH PRESSURE ALOFT SHIFTED OVER TO
FAR N MEXICO WHICH IN TURN EASED OUR STORM STEERING FLOW FROM A
GENERALLY N TO S DIRECTION TO A MORE W TO E DIRECTION. THIS
WILL...MAINLY AFTER TODAY...BRING IN SIGNIFICANTLY DRIER AIR ALOFT
WHICH WILL OF COURSE SIGNIFICANTLY CUT BACK SFC DEWPOINTS AND ALSO
CONVECTION. THIS STORM DOWNTURN WILL LAST AT LEAST INTO TUE AND MORE
THAN LIKELY WED AS WELL...IF NOT LONGER.
WHILE A LITTLE DRIER AIR MAY BEGIN TO PUSH INTO WESTERN NEW MEXICO
LATER TODAY...THERE SHOULD BE SUFFICIENT AMOUNTS REMAINING TO
TRIGGER A DECENT CROP OF SHOWERS AND STORMS. IT APPEARS THAT BEST
CHANCES FOR SUBSTANTIAL RAINFALL TODAY WILL BE NORTHERN MTNS AND
PERHAPS A LITTLE LESSER DEGREE THE SANDIAS SOUTHWARD TO THE
SACRAMENTOS AS WELL AS THE NE PLAINS WHERE A WEAK SFC BOUNDARY MAY
LINGER. WESTERLY WINDS WILL LIKELY BECOME SOMEWHAT GUSTY ALONG THE
CONTDVD AND ACROSS THE CENTRAL HIGHLANDS/WESTERN EAST CENTRAL PLAINS
THIS AFTN BUT LOW LEVEL MOISTURE IS NOT EXPECTED TO BE
SCOURED OUT SO MUCH THAT MIN RH VALUES FALL BELOW 15 PERCENT.
VENTILATION WILL IMPROVE SIGNIFICANTLY THIS AFTN.
DRYING TREND ACCELERATES MON WITH ONLY ISOLD CONVECTION IN THE
FORECAST FOR WESTERN AND SOUTHERN HIGH TERRAIN. WETTING RAIN STILL
IN CHANCE CATEGORY FROM THE SANGRE DE CRISTO MTS EASTWARD TO THE TX
BORDER...THOUGH NEARLY ALL AREAS OF N AND CENTRAL NM TO SEE FURTHER
REDUCTIONS IN WETTING RAIN COVERAGE AND POTENTIAL TUE AS DRYING
TREND MAY REACH ITS PEAK. VENTILATION WILL BE VERY GOOD TO EXCELLENT
FOR MOST OF THE FORECAST AREA. BOTH MIN AND MAX RH VALUES TREND
DOWNWARD AFFECTING OVERNIGHT RECOVERIES MON AND TUE NIGHT...ESPEC IN
THE NORTHWEST PLATEAU AND PORTIONS OF THE MIDDLE RIO GRANDE VALLEY.
STILL FAIRLY GOOD MODEL AGREEMENT ON A TREND OF MOISTURE RETURNING
DURING THE LATTER HALF NEXT WEEK AS THE UPPER HIGH CENTER SHIFTS
NORTHWARD OUT OF OLD MEXICO. THE FOCUS FOR WETTING RAIN WOULD APPEAR
TO BE THE NORTHERN AND WESTERN PORTIONS OF THE FCST AREA...BEARING A
LITTLE MORE RESEMBLANCE TO A TRADITIONAL MONSOON PATTERN...THOUGH
NOT AN ESPECIALLY STRONG ONE JUST YET.
43
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH FROM 11 AM MDT THIS MORNING THROUGH THIS EVENING
FOR THE FOLLOWING ZONES...NMZ501>529.
&&
$$
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
555 AM MDT SUN JUL 28 2013
.AVIATION...
12Z TAF CYCLE
VFR CONDITIONS LIKELY TO PERSIST THROUGH THE NEXT 24HRS OUTSIDE
OF SHRA AND TSRA. STRONGER TSRA WILL BE ABLE TO PRODUCE BRIEF MVFR
CIGS AND VSBY WITH THE MOST INTENSE PRODUCING VERY LOCALIZED IFR
CIGS AND VSBY. PEAK WIND GUSTS WITH THE STRONGEST ACTIVITY COULD
REACH 40 TO 55 KT. IN ADDITION...AT LEAST PARTIAL MT OBSCURATIONS
TO BE EXPECTED WITH THE MORE INTENSE ACTIVITY. GREATEST TSRA
COVERAGE MOST LIKELY TO BE ACROSS N MTS AND PERHAPS THE NE
HIGHLANDS AND PLAINS. ISOLATED TO LOCALLY SCATTERED COVERAGE
ELSEWHERE. THE ACTIVITY WILL DIMINISH LATER THIS EVE AND
OVERNIGHT.
43
&&
.PREV DISCUSSION...337 AM MDT SUN JUL 28 2013...
...LOCALLY HEAVY RAINFALL ON TAP FOR NEW MEXICO ONCE AGAIN TODAY...
SEVERAL VERY INTERESTING FEATURES AT PLAY TODAY WILL DEFINITELY MAKE
FOR A MORE ACTIVE DAY THAN SATURDAY. THE LATEST WATER VAPOR AND CIRA
BLENDED PW LOOPS SHOW A DEEPLY SATURATED ATMOSPHERE ENTRENCHED OVER
AZ AND NM. THE UPPER RIDGE CENTROID IS CLEARLY CENTERED OVER EL PASO.
A WELL DEFINED VORT MAX OVER SOUTHEASTERN AZ IS SLIDING NE ALONG THE
WESTERN PERIPHERY OF THE UPPER RIDGE. MEANWHILE AN ENTIRELY SEPARATE
AREA OF UPPER LEVEL INSTABILITY ASSOCIATED WITH AN UPPER SHORTWAVE
TROUGH STRETCHES FROM WESTERN AZ ENE INTO THE FOUR CORNERS REGION
AND SOUTHERN CO. SHOWERS AND STORMS HAVE BEEN ONGOING ACROSS BOTH
OF THESE AREAS ALL NIGHT.
THE 06Z AND LATEST HRRR HANDLE BOTH FEATURES VERY WELL. GUIDANCE ALSO
FALLS IN LINE WITH LATEST HPC QPF PROBABILITIES SO HAVE NUDGED POPS
UP QUITE A BIT TODAY. CONVECTIVE TEMPS INDICATED BY THE 06Z NAM OVER
THE REGION ARE VERY LOW SO CONFIDENCE IS HIGH THAT CONVECTION WILL
FIRE UP EARLY OVER WESTERN NM AND SHIFT EAST INTO THE RIO GRANDE
VALLEY BY EARLY AFTERNOON. THE VORT MAX LOOKS TO CROSS THE SOUTH
CENTRAL MTS BY MID AFTERNOON AND INCREASE THE POTENTIAL FOR FLASH
FLOODING OVER THE BURN SCARS WITHIN LINCOLN COUNTY. THE NORTH WILL
ALSO FIRE UP EARLY BUT CONTINUE LATER INTO THE EVENING AS STRONGER
UPPER DYNAMICS PUSH SLOWLY SOUTHEAST OVER THE AREA. SOME TRAINING
IS POSSIBLE ACROSS THIS AREA WHERE LOCALLY HEAVY RAINFALL IS LIKELY.
THE FARMINGTON AREA REALLY NEEDS THE RAIN AND TODAY SHOULD BE THE DAY.
THE DRYING TREND WILL COMMENCE MONDAY AND TUESDAY AS DRIER AIR FILTERS
INTO THE REGION FROM THE GREAT BASIN. THE GREATEST POTENTIAL FOR STORMS
WILL BE OVER THE NORTHERN HIGH TERRAIN WHERE MOISTURE RECYCLING WILL
BE MOST EFFICIENT. THE NE PLAINS WILL ALSO HAVE ELEVATED POPS AS A
WEAK BACK DOOR FRONTAL BOUNDARY SHIFTS SW INTO THE AREA. TUESDAY MAY
BE THE DRIEST DAY IN QUITE SOME TIME WITH MODEL GUIDANCE INDICATING
DEWPOINT VALUES RANGING FROM THE UPPER 20S ACROSS THE FAR NW PLATEAU
TO THE 40S OVER THE PLAINS.
THE UPPER HIGH WILL BUILD NORTHWEST OVER THE STATE AND STRENGTHEN TO
NEAR 596DM BY WEDNESDAY AND THURSDAY. THIS WILL INCREASE TEMPS BACK
SLIGHTLY ABOVE NORMAL AND REALLY FOCUS MOISTURE RECYCLING PROCESSES
IN AND IMMEDIATELY NEARBY THE HIGH TERRAIN WITH WEAK STEERING FLOW.
FLASH FLOOD THREAT MAY INCREASE ONCE AGAIN FOR BURN SCAR AREAS IN
THIS PATTERN. A STATIONARY PATTERN IS INDICATED BY THE GFS AND ECMWF
SOLUTION THURSDAY THROUGH NEXT WEEK WITH AN UPPER HIGH OVER WEST TX/
EASTERN NM AND A MOISTURE SURGE SLIDING NORTH OVER WESTERN NM. THIS
WILL BE A MUCH NEEDED WINDOW FOR PRECIP ACROSS THE GALLUP/FARMINGTON
AREA WHICH HAS BEEN RELATIVELY PARCHED THIS SUMMER.
GUYER
.FIRE WEATHER...
WX PATTERN CHANGE BEGAN SAT AS HIGH PRESSURE ALOFT SHIFTED OVER TO
FAR N MEXICO WHICH IN TURN EASED OUR STORM STEERING FLOW FROM A
GENERALLY N TO S DIRECTION TO A MORE W TO E DIRECTION. THIS
WILL...MAINLY AFTER TODAY...BRING IN SIGNIFICANTLY DRIER AIR ALOFT
WHICH WILL OF COURSE SIGNIFICANTLY CUT BACK SFC DEWPOINTS AND ALSO
CONVECTION. THIS STORM DOWNTURN WILL LAST AT LEAST INTO TUE AND MORE
THAN LIKELY WED AS WELL...IF NOT LONGER.
WHILE A LITTLE DRIER AIR MAY BEGIN TO PUSH INTO WESTERN NEW MEXICO
LATER TODAY...THERE SHOULD BE SUFFICIENT AMOUNTS REMAINING TO
TRIGGER A DECENT CROP OF SHOWERS AND STORMS. IT APPEARS THAT BEST
CHANCES FOR SUBSTANTIAL RAINFALL TODAY WILL BE NORTHERN MTNS AND
PERHAPS A LITTLE LESSER DEGREE THE SANDIAS SOUTHWARD TO THE
SACRAMENTOS AS WELL AS THE NE PLAINS WHERE A WEAK SFC BOUNDARY MAY
LINGER. WESTERLY WINDS WILL LIKELY BECOME SOMEWHAT GUSTY ALONG THE
CONTDVD AND ACROSS THE CENTRAL HIGHLANDS/WESTERN EAST CENTRAL PLAINS
THIS AFTN BUT LOW LEVEL MOISTURE IS NOT EXPECTED TO BE
SCOURED OUT SO MUCH THAT MIN RH VALUES FALL BELOW 15 PERCENT.
VENTILATION WILL IMPROVE SIGNIFICANTLY THIS AFTN.
DRYING TREND ACCELERATES MON WITH ONLY ISOLD CONVECTION IN THE
FORECAST FOR WESTERN AND SOUTHERN HIGH TERRAIN. WETTING RAIN STILL
IN CHANCE CATEGORY FROM THE SANGRE DE CRISTO MTS EASTWARD TO THE TX
BORDER...THOUGH NEARLY ALL AREAS OF N AND CENTRAL NM TO SEE FURTHER
REDUCTIONS IN WETTING RAIN COVERAGE AND POTENTIAL TUE AS DRYING
TREND MAY REACH ITS PEAK. VENTILATION WILL BE VERY GOOD TO EXCELLENT
FOR MOST OF THE FORECAST AREA. BOTH MIN AND MAX RH VALUES TREND
DOWNWARD AFFECTING OVERNIGHT RECOVERIES MON AND TUE NIGHT...ESPEC IN
THE NORTHWEST PLATEAU AND PORTIONS OF THE MIDDLE RIO GRANDE VALLEY.
STILL FAIRLY GOOD MODEL AGREEMENT ON A TREND OF MOISTURE RETURNING
DURING THE LATTER HALF NEXT WEEK AS THE UPPER HIGH CENTER SHIFTS
NORTHWARD OUT OF OLD MEXICO. THE FOCUS FOR WETTING RAIN WOULD APPEAR
TO BE THE NORTHERN AND WESTERN PORTIONS OF THE FCST AREA...BEARING A
LITTLE MORE RESEMBLANCE TO A TRADITIONAL MONSOON PATTERN...THOUGH
NOT AN ESPECIALLY STRONG ONE JUST YET.
43
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
337 AM MDT SUN JUL 28 2013
.DISCUSSION...
...LOCALLY HEAVY RAINFALL ON TAP FOR NEW MEXICO ONCE AGAIN TODAY...
SEVERAL VERY INTERESTING FEATURES AT PLAY TODAY WILL DEFINITELY MAKE
FOR A MORE ACTIVE DAY THAN SATURDAY. THE LATEST WATER VAPOR AND CIRA
BLENDED PW LOOPS SHOW A DEEPLY SATURATED ATMOSPHERE ENTRENCHED OVER
AZ AND NM. THE UPPER RIDGE CENTROID IS CLEARLY CENTERED OVER EL PASO.
A WELL DEFINED VORT MAX OVER SOUTHEASTERN AZ IS SLIDING NE ALONG THE
WESTERN PERIPHERY OF THE UPPER RIDGE. MEANWHILE AN ENTIRELY SEPARATE
AREA OF UPPER LEVEL INSTABILITY ASSOCIATED WITH AN UPPER SHORTWAVE
TROUGH STRETCHES FROM WESTERN AZ ENE INTO THE FOUR CORNERS REGION
AND SOUTHERN CO. SHOWERS AND STORMS HAVE BEEN ONGOING ACROSS BOTH
OF THESE AREAS ALL NIGHT.
THE 06Z AND LATEST HRRR HANDLE BOTH FEATURES VERY WELL. GUIDANCE ALSO
FALLS IN LINE WITH LATEST HPC QPF PROBABILITIES SO HAVE NUDGED POPS
UP QUITE A BIT TODAY. CONVECTIVE TEMPS INDICATED BY THE 06Z NAM OVER
THE REGION ARE VERY LOW SO CONFIDENCE IS HIGH THAT CONVECTION WILL
FIRE UP EARLY OVER WESTERN NM AND SHIFT EAST INTO THE RIO GRANDE
VALLEY BY EARLY AFTERNOON. THE VORT MAX LOOKS TO CROSS THE SOUTH
CENTRAL MTS BY MID AFTERNOON AND INCREASE THE POTENTIAL FOR FLASH
FLOODING OVER THE BURN SCARS WITHIN LINCOLN COUNTY. THE NORTH WILL
ALSO FIRE UP EARLY BUT CONTINUE LATER INTO THE EVENING AS STRONGER
UPPER DYNAMICS PUSH SLOWLY SOUTHEAST OVER THE AREA. SOME TRAINING
IS POSSIBLE ACROSS THIS AREA WHERE LOCALLY HEAVY RAINFALL IS LIKELY.
THE FARMINGTON AREA REALLY NEEDS THE RAIN AND TODAY SHOULD BE THE DAY.
THE DRYING TREND WILL COMMENCE MONDAY AND TUESDAY AS DRIER AIR FILTERS
INTO THE REGION FROM THE GREAT BASIN. THE GREATEST POTENTIAL FOR STORMS
WILL BE OVER THE NORTHERN HIGH TERRAIN WHERE MOISTURE RECYCLING WILL
BE MOST EFFICIENT. THE NE PLAINS WILL ALSO HAVE ELEVATED POPS AS A
WEAK BACK DOOR FRONTAL BOUNDARY SHIFTS SW INTO THE AREA. TUESDAY MAY
BE THE DRIEST DAY IN QUITE SOME TIME WITH MODEL GUIDANCE INDICATING
DEWPOINT VALUES RANGING FROM THE UPPER 20S ACROSS THE FAR NW PLATEAU
TO THE 40S OVER THE PLAINS.
THE UPPER HIGH WILL BUILD NORTHWEST OVER THE STATE AND STRENGTHEN TO
NEAR 596DM BY WEDNESDAY AND THURSDAY. THIS WILL INCREASE TEMPS BACK
SLIGHTLY ABOVE NORMAL AND REALLY FOCUS MOISTURE RECYCLING PROCESSES
IN AND IMMEDIATELY NEARBY THE HIGH TERRAIN WITH WEAK STEERING FLOW.
FLASH FLOOD THREAT MAY INCREASE ONCE AGAIN FOR BURN SCAR AREAS IN
THIS PATTERN. A STATIONARY PATTERN IS INDICATED BY THE GFS AND ECMWF
SOLUTION THURSDAY THROUGH NEXT WEEK WITH AN UPPER HIGH OVER WEST TX/
EASTERN NM AND A MOISTURE SURGE SLIDING NORTH OVER WESTERN NM. THIS
WILL BE A MUCH NEEDED WINDOW FOR PRECIP ACROSS THE GALLUP/FARMINGTON
AREA WHICH HAS BEEN RELATIVELY PARCHED THIS SUMMER.
GUYER
&&
.FIRE WEATHER...
WX PATTERN CHANGE BEGAN SAT AS HIGH PRESSURE ALOFT SHIFTED OVER TO
FAR N MEXICO WHICH IN TURN EASED OUR STORM STEERING FLOW FROM A
GENERALLY N TO S DIRECTION TO A MORE W TO E DIRECTION. THIS
WILL...MAINLY AFTER TODAY...BRING IN SIGNIFICANTLY DRIER AIR ALOFT
WHICH WILL OF COURSE SIGNIFICANTLY CUT BACK SFC DEWPOINTS AND ALSO
CONVECTION. THIS STORM DOWNTURN WILL LAST AT LEAST INTO TUE AND MORE
THAN LIKELY WED AS WELL...IF NOT LONGER.
WHILE A LITTLE DRIER AIR MAY BEGIN TO PUSH INTO WESTERN NEW MEXICO
LATER TODAY...THERE SHOULD BE SUFFICIENT AMOUNTS REMAINING TO
TRIGGER A DECENT CROP OF SHOWERS AND STORMS. IT APPEARS THAT BEST
CHANCES FOR SUBSTANTIAL RAINFALL TODAY WILL BE NORTHERN MTNS AND
PERHAPS A LITTLE LESSER DEGREE THE SANDIAS SOUTHWARD TO THE
SACRAMENTOS AS WELL AS THE NE PLAINS WHERE A WEAK SFC BOUNDARY MAY
LINGER. WESTERLY WINDS WILL LIKELY BECOME SOMEWHAT GUSTY ALONG THE
CONTDVD AND ACROSS THE CENTRAL HIGHLANDS/WESTERN EAST CENTRAL PLAINS
THIS AFTN BUT LOW LEVEL MOISTURE IS NOT EXPECTED TO BE
SCOURED OUT SO MUCH THAT MIN RH VALUES FALL BELOW 15 PERCENT.
VENTILATION WILL IMPROVE SIGNIFICANTLY THIS AFTN.
DRYING TREND ACCELERATES MON WITH ONLY ISOLD CONVECTION IN THE
FORECAST FOR WESTERN AND SOUTHERN HIGH TERRAIN. WETTING RAIN STILL
IN CHANCE CATEGORY FROM THE SANGRE DE CRISTO MTS EASTWARD TO THE TX
BORDER...THOUGH NEARLY ALL AREAS OF N AND CENTRAL NM TO SEE FURTHER
REDUCTIONS IN WETTING RAIN COVERAGE AND POTENTIAL TUE AS DRYING
TREND MAY REACH ITS PEAK. VENTILATION WILL BE VERY GOOD TO EXCELLENT
FOR MOST OF THE FORECAST AREA. BOTH MIN AND MAX RH VALUES TREND
DOWNWARD AFFECTING OVERNIGHT RECOVERIES MON AND TUE NIGHT...ESPEC IN
THE NORTHWEST PLATEAU AND PORTIONS OF THE MIDDLE RIO GRANDE VALLEY.
STILL FAIRLY GOOD MODEL AGREEMENT ON A TREND OF MOISTURE RETURNING
DURING THE LATTER HALF NEXT WEEK AS THE UPPER HIGH CENTER SHIFTS
NORTHWARD OUT OF OLD MEXICO. THE FOCUS FOR WETTING RAIN WOULD APPEAR
TO BE THE NORTHERN AND WESTERN PORTIONS OF THE FCST AREA...BEARING A
LITTLE MORE RESEMBLANCE TO A TRADITIONAL MONSOON PATTERN...THOUGH
NOT AN ESPECIALLY STRONG ONE JUST YET.
43
&&
.AVIATION...
06Z TAF CYCLE
VFR TERMINALS FORECAST TO PERSIST THROUGH THE NEXT 24HRS OUTSIDE
OF SHOWERS AND THUNDERSTORMS. SCATTERED COVERAGE FORECAST SUNDAY
AFTERNOON AND EVENING NEAR KLVS AND KTCC...OTHERWISE ISOLATED
COVERAGE. WESTERLIES ARE ON THE INCREASE IN THE LOWER LEVELS OF
THE ATMOSPHERE AND SUNDAY AFTERNOON WILL FEATURE STRONGER WINDS
THAN SATURDAY`S...WITH GUSTS BETWEEN 25-28KTS AT KLVS AND KTCC.
11
&&
.PRELIMINARY POINT TEMPS/POPS...
FARMINGTON...................... 86 64 91 62 / 60 30 5 5
DULCE........................... 81 52 84 51 / 70 30 10 5
CUBA............................ 82 53 86 54 / 50 30 10 10
GALLUP.......................... 82 58 85 56 / 30 20 10 5
EL MORRO........................ 76 53 80 52 / 40 20 10 10
GRANTS.......................... 81 58 86 57 / 50 20 5 5
QUEMADO......................... 79 56 83 55 / 40 20 10 5
GLENWOOD........................ 84 60 87 58 / 30 20 5 5
CHAMA........................... 71 49 75 49 / 60 40 20 10
LOS ALAMOS...................... 78 58 82 58 / 40 30 10 10
PECOS........................... 74 57 79 57 / 60 30 10 10
CERRO/QUESTA.................... 77 53 79 53 / 50 40 20 20
RED RIVER....................... 68 46 71 47 / 60 50 30 30
ANGEL FIRE...................... 72 45 75 44 / 60 50 20 20
TAOS............................ 80 52 83 52 / 40 30 10 10
MORA............................ 75 53 79 53 / 60 50 20 10
ESPANOLA........................ 83 59 87 57 / 40 20 5 5
SANTA FE........................ 78 58 82 59 / 40 30 10 10
SANTA FE AIRPORT................ 82 60 85 60 / 40 30 5 5
ALBUQUERQUE FOOTHILLS........... 85 65 87 66 / 50 20 5 5
ALBUQUERQUE HEIGHTS............. 87 67 89 67 / 40 20 5 0
ALBUQUERQUE VALLEY.............. 89 67 93 65 / 40 20 5 5
ALBUQUERQUE WEST MESA........... 90 66 94 66 / 30 20 5 5
LOS LUNAS....................... 88 65 92 64 / 40 20 5 5
RIO RANCHO...................... 90 65 93 65 / 40 20 5 5
SOCORRO......................... 91 66 97 67 / 50 20 5 5
SANDIA PARK/CEDAR CREST......... 82 59 85 60 / 60 30 10 5
TIJERAS......................... 83 60 86 61 / 60 20 10 5
MORIARTY/ESTANCIA............... 83 59 86 59 / 60 30 10 5
CLINES CORNERS.................. 79 59 83 60 / 60 30 10 5
GRAN QUIVIRA.................... 81 59 86 61 / 60 30 10 0
CARRIZOZO....................... 82 64 89 65 / 50 20 5 5
RUIDOSO......................... 74 57 81 59 / 60 30 20 5
CAPULIN......................... 78 55 81 57 / 60 60 30 30
RATON........................... 83 57 86 58 / 60 50 20 20
SPRINGER........................ 84 57 87 58 / 60 50 20 20
LAS VEGAS....................... 80 57 84 57 / 60 40 10 10
CLAYTON......................... 86 63 87 65 / 30 50 20 20
ROY............................. 82 62 87 63 / 50 50 20 20
CONCHAS......................... 90 68 95 69 / 30 30 10 10
SANTA ROSA...................... 89 67 93 67 / 40 30 10 5
TUCUMCARI....................... 93 71 98 71 / 20 30 10 10
CLOVIS.......................... 89 67 94 68 / 20 20 10 5
PORTALES........................ 89 67 94 68 / 20 20 10 5
FORT SUMNER..................... 89 69 95 69 / 30 20 10 5
ROSWELL......................... 91 71 98 71 / 20 20 10 5
PICACHO......................... 85 63 91 64 / 30 20 10 5
ELK............................. 77 60 82 61 / 50 30 20 5
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS RALEIGH NC
945 PM EDT MON JUL 29 2013
.SYNOPSIS...
A STATIONARY FRONT WILL LINGER OVER SOUTHEAST NC THROUGH
TUESDAY...WHILE WEAK HIGH PRESSURE WILL BUILD FROM THE CENTRAL
APPALACHIANS INTO CENTRAL AND WESTERN NC.
&&
.NEAR TERM /TONIGHT/...
AS OF 945 PM MONDAY...
THE LATEST SURFACE ANALYSIS SHOWED A SURFACE FRONT NEARLY STATIONARY
OVER THE SOUTHEAST PART OF CENTRAL NORTH CAROLINA. AS OUTFLOW FROM
DEEP CONVECTION ALONG THE COAST MOVED NORTHWEST...THIS SUPPORTED
SOME SHORT-LIVED STRENGTHENING OF SHOWERS AND THUNDERSTORMS THAT
DEVELOPED IN VICINITY OF KFAY AND KMEB. THESE SHOWERS AND STORMS
HAVE CERTAINLY WANED DURING THE MID-EVENING HOURS...AND BUFR
SOUNDINGS FROM BOTH THE NAM AND THE GFS...ALONG WITH OUTPUT FROM THE
RUC AND MOST RECENT HRRR WRF...SHOW THAT THE POTENTIAL FOR DEEP
CONVECTION OVERNIGHT SHOULD BE LIMITED. 850MB SUBSIDENCE IS FORECAST
BY THE RUC OVERNIGHT...AND THOSE BUFR SOUNDINGS INDICATE SLIGHT
WARMING AND RELAXING OF LAPSE RATES ALOFT OVERNIGHT. FOR THE REST OF
THE EVENING...MAINTAINED A SLIGHT CHANCE OF A SHOWER OR THUNDERSTORM
SOUTH OF A LINE FROM ABOUT GOLDSBORO TO ROCKINGHAM...WITH A CHANCE
IN VICINITY OF KCTZ. OVERNIGHT...IN THE DEEPER MOISTURE SOUTH OF THE
FRONT...MAINTAINED A SLIGHT CHANCE OF A SHOWER ONLY OVER THE LATTER.
THE IR SATELLITE IMAGES SHOW PATCHES OF CI AND AC IN THE NORTHWEST
FLOW ALOFT BEHIND THE TROUGH AXIS. WHILE THE GFS BUFR SOUNDINGS ARE
VERY DRY ALOFT...THE NAM SHOWS A NARROW VOLUME OF MOISTURE ALOFT AT
MOST SITES THROUGH THE OVERNIGHT HOURS. BASED ON THE SATELLITE
IMAGES...THE NAM MAY BE VERIFYING BEST...AND PARTLY CLOUDY
CONDITIONS ARE FORECAST ON AVERAGE FOR THE OVERNIGHT. ANTICIPATE THE
DEVELOPMENT OF SOME LOW CLOUDS AND PATCHY FOG ESPECIALLY OVER THE
SOUTHEAST PART OF CENTRAL NORTH CAROLINA OVERNIGHT...IN THE BETTER
MOISTURE AND WHERE SCATTERED SHOWERS OCCURRED DURING THE DAY AND
EARLY EVENING. LOWERED MINS A BIT ESPECIALLY TOWARD KTDF...AND
KHNZ...WHERE TEMPERATURES DURING THE EVENING WERE FALLING QUICKLY
AND READINGS NEAR 60 APPEARED LIKELY. IN FACT...A COUPLE OF UPPER
50S ARE POSSIBLE TOWARD THE VIRGINIA BORDER. OVERNIGHT LOWS IN THE
60S.
&&
.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
AS OF 225 PM MONDAY...
WITH ZONAL FLOW ALOFT AND HIGH PRESSURE TO OUR NORTH MOST OF THE
DAY...THE AFOREMENTIONED FRONT WILL REMAIN POSITIONED NEAR OR
PERHAPS A BIT FURTHER SOUTH THAN ITS CURRENT POSITION. WITH MOST OF
OUR CWA ON THE DRIER MORE STABLE SIDE OF THE BOUNDARY...FOR NOW THE
ONLY PLACE WE`LL CARRY SLIGHT CHANCE POPS DURING THE DAY WILL BE
ACROSS OUR FAR S/SE ZONES. HIGHS WILL ONCE AGAIN RANGE FROM THE MID
80S NW TO UPPER 80S SE...WHICH IS A DEGREE OR TWO BELOW NORMAL.
CLOUDS WILL BE ON THE INCREASE TUESDAY NIGHT AS THE SHORT WAVE
THAT`S CURRENTLY OVER THE CENTRAL PLAINS MOVES EAST AND APPROACHES
THE CAROLINAS. IF THIS SYSTEM SPEEDS UP...SOME LIGHT SHOWER ACTIVITY
MAY MOVE INTO OUR WESTERN ZONES BEFORE SUNRISE. WILL INCLUDE SLIGHT
CHANCE POPS ACROSS OUR WESTERN ZONES TUESDAY NIGHT TO ACCOUNT FOR
THIS POSSIBILITY. SLIGHTLY WARMER LOWS CAN BE EXPECTED DUE TO THE
ADDITIONAL CLOUD COVER...UPPER 60S NW TO LOWER 70S SE.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
AS OF 250 PM MONDAY...
OVERALL THE LONG TERM PERIOD WILL FEATURE A MEAN TROUGH ACROSS THE
EASTERN CONUS WITH A SERIES OF SHORTWAVES/WEAK FRONTS PROGRESSING
THROUGH THE AREA. THIS SET-UP WILL KEEP THE SUMMER HEAT AT BAY WHILE
PROVIDING PERIODS OF INCREASED SHOWER AND THUNDERSTORM ACTIVITY.
THIS NEXT UPPER TROUGH/SURFACE COLD FRONT IS PROGGED TO APPROACH AND
SLOWLY CROSS THE REGION WEDNESDAY INTO THURSDAY. MODELS HAVE SHOWN
SOMEWHAT OF A SLOWING TREND THE PAST COUPLE OF DAYS (ESPECIALLY THE
GFS)...BUT FOR NOW IT STILL APPEARS THAT THE BEST CHANCE OF RAIN
WILL OCCUR LATE WEDNESDAY INTO THURSDAY (ALTHOUGH CURRENT GFS SHOWS
THE SIGNIFICANT PRECIP ASSOCIATED WITH THE FRONT HOLDING OFF UNTIL
THURSDAY AND PERSISTING MORE INTO FRIDAY). NEVERTHELESS...WILL STILL
SHOW POPS INCREASING FROM WEST TO EAST ON WEDNESDAY AND THEN
GRADUALLY DECREASING IN THE SAME FASHION LATE THURSDAY.
BY FRIDAY...THE FRONT SHOULD STALL/WASH OUT SOMEWHERE NEAR THE
REGION. OVERALL...THE ECMWF HAS BEEN FAIRLY CONSISTENT WITH PUSHING
IT SOUTH/EAST OF THE FORECAST AREA WHICH WOULD RESULT IN MOSTLY DRY
CONDITIONS FOR CENTRAL NC...WHILE THE GFS IS SLOWER WITH THE
EASTWARD PROGRESSION (SEE ABOVE PARAGRAPH). HOWEVER...GIVEN THE TIME
OF THE YEAR AND RECENT EVENTS...WILL MAINTAIN AT LEAST A MENTION OF
PRECIP FOR FRIDAY AND SATURDAY...ESPECIALLY ON FRIDAY AND MOSTLY
ACROSS THE EASTERN/SOUTHERN PORTIONS OF THE FORECAST AREA...WITH ANY
ACTIVITY BEING MOSTLY DIURNAL IN NATURE. YET ANOTHER NEXT SYSTEM
WILL APPROACH THE AREA LATE IN THE WEEKEND/EARLY NEXT WEEK (ALTHOUGH
TIMING IS IN QUESTION AT THIS TIME).
TEMPS WILL ULTIMATELY BE DEPENDENT ON THE EXACT TIMING/EXTENT OF ANY
PRECIP THAT OCCURS...BUT SHOULD LARGELY BE NEAR TO SLIGHTLY BELOW
NORMAL THROUGH THE PERIOD.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
AS OF 810 PM MONDAY...
A FRONTAL ZONE - ENHANCED AND DRAWN NORTHWESTWARD TO NEAR BUT LIKELY
JUST SOUTHEAST OF KRDU - WILL SEPARATE DRY AIR AND ASSOCIATED VFR
CONDITIONS AT TRIAD TERMINALS AND KRDU...FROM STILL HUMID AIR AND
ASSOCIATED LATE NIGHT-EARLY TUE MVFR-LIFR VISIBILITY RESTRICTIONS
AND SCT TO BKN STRATUS AROUND 500 FEET AT KFAY AND KRWI.
OTHERWISE...AN ISOLATED SHOWER OR STORM WILL REMAIN IN THE VICINITY
OF KFAY THROUGH 01Z...WITH WINDS AT ALL TAF SITES LIGHT AND VARIABLE
TO NORTHEASTERLY THROUGHOUT THE PERIOD.
LOOKING AHEAD: LIGHT FOG OR STRATUS PROBABLE AGAIN AT KFAY AND KRWI
WED MORNING...WITH IFR STRATUS PROBABLE AT MOST OR ALL TAF SITES THU
AND FRI MORNINGS. THE CHANCE FOR MAINLY AFTERNOON AND EVENING STORMS
WILL BE HIGHEST WED AND THU...WITH OTHERWISE ONLY ISOLATED ACTIVITY
EXPECTED.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MWS
NEAR TERM...DJF
SHORT TERM...NP
LONG TERM...KRR
AVIATION...MWS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
930 PM CDT MON JUL 29 2013
.UPDATE...
ISSUED AT 930 PM CDT MON JUL 29 2013
CURRENT RADAR SHOWING LINE OF SHOWERS PARALLEL AND JUST WEST OF
RRV. CTG LIGHTNING HAS DECREASED AND ONLY STRIKE ON NLDN IS NOW IN
VICINITY OF VALLEY CITY. EXPECT THIS WILL DIE OFF IN THE NEXT 30
MIN OR SO AND HAVE WENT TO ALL SHOWERS FOR REMAINDER OF THE NIGHT.
MAIN FORECAST CHANGE IS SLOWING DOWN EASTWARD PROGRESSION AND ALSO
BEGINNING TO REMOVE POPS FROM SOUTHERN END OF LINE AS SHOWERS
PROGRESS EASTWARD. DO NOT LOOK FOR ANY SHOWERS ALONG SOUTHERN TIER
OF ZONES. ALSO PULLING POPS BEHIND LINE IN THE DVL BASIN UP
THROUGH TOWNER COUNTY. NO SIG CHANGES TO TEMPS ANTICIPATED.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 338 PM CDT MON JUL 29 2013
FORECAST CHALLENGES INCLUDE CONVECTIVE CHANCES TONIGHT THROUGH
TOMORROW NIGHT. GFS/NAM/ECMWF/GEM SYNOPTIC FIELDS IN GOOD OVERALL
AGREEMENT...BUT DIFFER SOMEWHAT WITH THE MESOSCALE DETAILS. WILL
USE THE RAP FOR THE ONGOING CONVECTION ACROSS CENTRAL ND THIS
EVENING AND TONIGHT...SHIFTING TO A MODEL BLEND FOR THE REMAINDER
OF THE SHORT-TERM.
20 UTC REGIONAL RADARS SHOW THE SHOWERS ACROSS NORTHEAST SD HAVE
BARELY MOVED INTO THE SOUTHERN VALLEY WITH PERHAPS A FEW SPRINKLES
FALLING ACROSS THE LAKES COUNTRY OF WEST CENTRAL MN. WILL KEEP 20
TO 30 POPS IN THESE AREAS THROUGH THE EARLY EVENING AFTER WHICH ANY
REMAINING ACTIVITY SHOULD DISSIPATE. IN ADDITION...THE ORIGINAL
LINE OF CONVECTION AHEAD OF THE SURFACE TROUGH THIS MORNING HAS
DISSIPATED AND GIVEN WAY TO A STRONGER LINE NOW STRETCHING FROM
NORTHWEST OF MINOT TO SOUTHWEST OF BISMARCK...MOVING TO THE EAST
AROUND 25 KTS. THESE THUNDERSTORMS ARE ALIGNED ALONG THE SURFACE
BOUNDARY NEAR THE AXIS OF GREATEST INSTABILITY. AS THE SHORT-WAVE
ALOFT PROPAGATES ACROSS EASTERN ND AND NORTHWEST MN THIS EVENING
AND OVERNIGHT...THESE STORMS WILL CONTINUE TO MOVE ACROSS ND/MN.
HOWEVER...INSTABILITY IS WEAK ALONG AND EAST OF THE VALLEY...SO
THE EXTENT TO WHICH THEY HOLD TOGETHER IS IN QUESTION. THE RAP
WITH SUPPORT FROM THE GFS/NAM DISSIPATE THESE STORMS EAST OF THE
VALLEY AND IF THIS VERIFIES...CURRENT POPS MAY BE TOO HIGH. GIVEN
HIGHER INSTABILITY TO THE WEST...SOME THUNDERSTORMS COULD BE STRONG
AND EVEN SEVERE ACROSS THE DEVILS LAKE BASIN. HOWEVER...NO SEVERE
CONVECTION IS EXPECTED ALONG AND EAST OF THE VALLEY.
MUCH OF TUESDAY SHOULD BE DRY AS THE REGION IS BETWEEN WEATHER
SYSTEMS...BUT SHOWER AND THUNDERSTORM CHANCES INCREASE AGAIN LATE
IN THE DAY AND OVERNIGHT AS A STRONG CANADIAN SHORT-WAVE AND
ASSOCIATED COLD FRONT MOVE ACROSS THE FORECAST AREA. THE HIGHEST
INSTABILITY WILL REMAIN ACROSS SD INTO SOUTHWEST MN...BUT MODELS
INDICATE MLCAPE UP TO 1500 J/KG MAINLY ALONG AND SOUTH OF THE I-94
CORRIDOR BY TUESDAY AFTERNOON. WITH THE APPROACHING COLD FRONT AND
50+ KTS OF 0 TO 6 KM BULK SHEAR ASSOCIATED WITH A 60 TO 80 KT 300
HPA JET STREAK...MODELS HINT AT A CONVECTIVE COMPLEX DEVELOPING
SOMEWHERE NEAR THE ND/SD BORDER. SPC DAY 2 CONVECTIVE OUTLOOK
SHOWS A SLIGHT RISK FOR SEVERE CONVECTION IN THIS AREA AND THIS
SEEMS REASONABLE. EXACT PLACEMENT OF ANY COMPLEX THAT DOES DEVELOP
IS UNCERTAIN AS IS THE EASTWARD EXTENT TO THE SEVERE POTENTIAL...
SO SOMETHING TO FINE-TUNE IN THE NEXT FORECAST PACKAGE IF POSSIBLE.
THERMAL RIDGE AXIS MOVES OVERHEAD IN FRONT OF THE COLD FRONT...SO
HIGHS TUESDAY WILL REACH THE UPPER 70S TO NEAR 80 DEGREES.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 338 PM CDT MON JUL 29 2013
WEDNESDAY AND THURSDAY WILL BE DRY WITH SURFACE HIGH PRESSURE
BUILDING ACROSS THE FORECAST AREA. TEMPERATURES WILL BE A BIT
COOLER WITH HIGHS IN THE 70S AND LOWS IN THE 50S. WINDS WILL BE
BREEZY FROM THE NORTHWEST WEDNESDAY BEFORE BECOMING LIGHT ON
THURSDAY AS THE PRESSURE GRADIENT RELAXES.
HIGH PRESSURE WILL REMAIN FROM MANITOBA INTO EASTERN NORTH DAKOTA
FRIDAY INTO SATURDAY KEEPING US DRY WITH TEMPERATURES REMAINING
NEARLY 10 DEGREES BELOW AVERAGE. HIGH PRESSURE MOVES EAST INTO THE
WESTERN GREAT LAKES REGION BY LATE SUNDAY ALLOWING NEXT SHORT WAVE
AND SURFACE LOW TO MOVE INTO THE NORTHERN PLAINS. THIS SYSTEM WILL
GIVE THE RISK OF SHOWERS AND THUNDERSTORMS SUNDAY TO EASTERN NORTH
DAKOTA AND PARTS OF WESTERN MINNESOTA...WHILE EASTERN FCST AREA WILL
REMAIN DRY. WILL GO WITH MOSTLY 30-40 POPS MONDAY AS SYSTEM MOVES
THROUGH.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 930 PM CDT MON JUL 29 2013
UPDATED GFK AND TVF FOR TIMING OF SHOWERS INTO AERODROME AREA AND
REMOVED PRECIP FROM DVL. ALSO NEEDED TO ADD MENTION OF SHOWERS TO
DVL AS SHOWERS ENTER FAR WESTERN CLAY COUNTY. LOWER CIGS BEING
REPORTED BEHIND LINE OF SHOWERS...AROUND 3500 FT AT DVL. WILL NEED
TO MONITOR FOR CIGS LOWERING INTO MVFR RANGE PER MOS
GUIDANCE...BUT WOULD EXPECT ONLY DVL DUE TO SLIGHTLY HIGHER ELEVATION.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...SPEICHER
SHORT TERM...ROGERS
LONG TERM...ROGERS/RIDDLE
AVIATION...SPEICHER
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
703 PM CDT MON JUL 29 2013
.UPDATE...
ISSUED AT 703 PM CDT MON JUL 29 2013
PRIMARY CHALLENGE FOR THIS EVENING IS TIMING FOR FORWARD EDGE OF
SHOWERS/TSTMS. 00Z NAM FROM LAST NIGHT ACTUALLY VERIFYING QUITE
WELL KEEPING THE VALLEY DRY UNTIL AT LEAST 00Z. EARLY IN SHIFT DID
AN UPDATE TO REMOVE INHERITED POPS FOR CENTRAL AND NORTHERN VALLEY
UNTIL AFT 00Z. CONVECTION JUST NOW MAKING DVL. LATEST RAP RUN IS
ABOUT 2 HRS TOO FAST AND HAVE TRIMMED BACK PRECIP ON MN SIDE OF
CWA UNTIL LATE EVENING. LIKELY STILL HAVE POPS REACHING THE RIVER
A BIT TOO FAST. HAVE ALSO CHANGED TO SHOWERS WITH ISOLD TSTMS AFT
04Z AND ALL SHOWERS AFT 06Z AS INSTABILITY CONTINUES TO WEAKEN.
HAD PLANNED ON PULLING POPS FROM ABOUT HILLSBORO SOUTH HOWEVER
RADAR NOW SHOWING A LINE OF WEAK SHOWERS IN RANSOM/SARGENT SO WILL
KEEP ISOLD THUNDER IN FOR EARLY EVENING AND REASSESS ON 10 PM CDT
UPDATE. HAVE ALSO LOWERED POPS FOR NORTHEASTERN ZONES AS RAP
BEGINS TO FOCUS ON SOUTHERN MB BY LATE EVENING...HOWEVER 12Z WRF
DID SHOW ACTIVITY MUCH FURTHER SOUTH (BELIEVE IT IS OVERDONE).
WILL SEE HOW TONIGHTS 00Z RUN LOOKS AND TOUCH UP MN SIDE MORE FOR
NEXT UPDATE.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 338 PM CDT MON JUL 29 2013
FORECAST CHALLENGES INCLUDE CONVECTIVE CHANCES TONIGHT THROUGH
TOMORROW NIGHT. GFS/NAM/ECMWF/GEM SYNOPTIC FIELDS IN GOOD OVERALL
AGREEMENT...BUT DIFFER SOMEWHAT WITH THE MESOSCALE DETAILS. WILL
USE THE RAP FOR THE ONGOING CONVECTION ACROSS CENTRAL ND THIS
EVENING AND TONIGHT...SHIFTING TO A MODEL BLEND FOR THE REMAINDER
OF THE SHORT-TERM.
20 UTC REGIONAL RADARS SHOW THE SHOWERS ACROSS NORTHEAST SD HAVE
BARELY MOVED INTO THE SOUTHERN VALLEY WITH PERHAPS A FEW SPRINKLES
FALLING ACROSS THE LAKES COUNTRY OF WEST CENTRAL MN. WILL KEEP 20
TO 30 POPS IN THESE AREAS THROUGH THE EARLY EVENING AFTER WHICH ANY
REMAINING ACTIVITY SHOULD DISSIPATE. IN ADDITION...THE ORIGINAL
LINE OF CONVECTION AHEAD OF THE SURFACE TROUGH THIS MORNING HAS
DISSIPATED AND GIVEN WAY TO A STRONGER LINE NOW STRETCHING FROM
NORTHWEST OF MINOT TO SOUTHWEST OF BISMARCK...MOVING TO THE EAST
AROUND 25 KTS. THESE THUNDERSTORMS ARE ALIGNED ALONG THE SURFACE
BOUNDARY NEAR THE AXIS OF GREATEST INSTABILITY. AS THE SHORT-WAVE
ALOFT PROPAGATES ACROSS EASTERN ND AND NORTHWEST MN THIS EVENING
AND OVERNIGHT...THESE STORMS WILL CONTINUE TO MOVE ACROSS ND/MN.
HOWEVER...INSTABILITY IS WEAK ALONG AND EAST OF THE VALLEY...SO
THE EXTENT TO WHICH THEY HOLD TOGETHER IS IN QUESTION. THE RAP
WITH SUPPORT FROM THE GFS/NAM DISSIPATE THESE STORMS EAST OF THE
VALLEY AND IF THIS VERIFIES...CURRENT POPS MAY BE TOO HIGH. GIVEN
HIGHER INSTABILITY TO THE WEST...SOME THUNDERSTORMS COULD BE STRONG
AND EVEN SEVERE ACROSS THE DEVILS LAKE BASIN. HOWEVER...NO SEVERE
CONVECTION IS EXPECTED ALONG AND EAST OF THE VALLEY.
MUCH OF TUESDAY SHOULD BE DRY AS THE REGION IS BETWEEN WEATHER
SYSTEMS...BUT SHOWER AND THUNDERSTORM CHANCES INCREASE AGAIN LATE
IN THE DAY AND OVERNIGHT AS A STRONG CANADIAN SHORT-WAVE AND
ASSOCIATED COLD FRONT MOVE ACROSS THE FORECAST AREA. THE HIGHEST
INSTABILITY WILL REMAIN ACROSS SD INTO SOUTHWEST MN...BUT MODELS
INDICATE MLCAPE UP TO 1500 J/KG MAINLY ALONG AND SOUTH OF THE I-94
CORRIDOR BY TUESDAY AFTERNOON. WITH THE APPROACHING COLD FRONT AND
50+ KTS OF 0 TO 6 KM BULK SHEAR ASSOCIATED WITH A 60 TO 80 KT 300
HPA JET STREAK...MODELS HINT AT A CONVECTIVE COMPLEX DEVELOPING
SOMEWHERE NEAR THE ND/SD BORDER. SPC DAY 2 CONVECTIVE OUTLOOK
SHOWS A SLIGHT RISK FOR SEVERE CONVECTION IN THIS AREA AND THIS
SEEMS REASONABLE. EXACT PLACEMENT OF ANY COMPLEX THAT DOES DEVELOP
IS UNCERTAIN AS IS THE EASTWARD EXTENT TO THE SEVERE POTENTIAL...
SO SOMETHING TO FINE-TUNE IN THE NEXT FORECAST PACKAGE IF POSSIBLE.
THERMAL RIDGE AXIS MOVES OVERHEAD IN FRONT OF THE COLD FRONT...SO
HIGHS TUESDAY WILL REACH THE UPPER 70S TO NEAR 80 DEGREES.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 338 PM CDT MON JUL 29 2013
WEDNESDAY AND THURSDAY WILL BE DRY WITH SURFACE HIGH PRESSURE
BUILDING ACROSS THE FORECAST AREA. TEMPERATURES WILL BE A BIT
COOLER WITH HIGHS IN THE 70S AND LOWS IN THE 50S. WINDS WILL BE
BREEZY FROM THE NORTHWEST WEDNESDAY BEFORE BECOMING LIGHT ON
THURSDAY AS THE PRESSURE GRADIENT RELAXES.
HIGH PRESSURE WILL REMAIN FROM MANITOBA INTO EASTERN NORTH DAKOTA
FRIDAY INTO SATURDAY KEEPING US DRY WITH TEMPERATURES REMAINING
NEARLY 10 DEGREES BELOW AVERAGE. HIGH PRESSURE MOVES EAST INTO THE
WESTERN GREAT LAKES REGION BY LATE SUNDAY ALLOWING NEXT SHORT WAVE
AND SURFACE LOW TO MOVE INTO THE NORTHERN PLAINS. THIS SYSTEM WILL
GIVE THE RISK OF SHOWERS AND THUNDERSTORMS SUNDAY TO EASTERN NORTH
DAKOTA AND PARTS OF WESTERN MINNESOTA...WHILE EASTERN FCST AREA WILL
REMAIN DRY. WILL GO WITH MOSTLY 30-40 POPS MONDAY AS SYSTEM MOVES
THROUGH.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 703 PM CDT MON JUL 29 2013
VFR CIGS WITH TSTMS AT DVL OVER NEXT COUPLE OF HOURS...AND SHRA
REACHING GFK/TVF MID TO LATE EVENING. NOT ENOUGH CONFIDENCE FOR
PRECIP AT BJI/FAR TO MENTION...BUT WILL CONTINUE TO MONITOR
ACTIVITY OVER JMS AND MAY NEED TO UPDATE FAR IF IT HOLDS TOGETHER.
MODEL GUIDANCE WEAKENS THIS CLUSTER BY THE TIME IT REACHES FAR.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...SPEICHER
SHORT TERM...ROGERS
LONG TERM...ROGERS/RIDDLE
AVIATION...SPEICHER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1212 PM CDT SUN JUL 28 2013
.UPDATE...
ISSUED AT 1211 PM CDT SUN JUL 28 2013
THE LATEST VISIBLE SATELLITE IMAGERY SHOWS A SCT CIRRUS SHIELD
ADVANCING FROM WESTERN NORTH DAKOTA INTO PORTIONS OF CENTRAL NORTH
DAKOTA. ADJUSTED SKY GRIDS UPWARD WITH ADVANCING CLOUDS FOR THIS
AFTERNOON. WATER VAPOR IMAGERY SHOWS A COUPLE OF SHORTWAVES...ONE
IN SOUTHERN SASKATCHEWAN MOVING NORTHEAST WITH TIME...WITH ANOTHER
ALONG THE WESTERN BORDER MOVING EAST. REGIONAL RADAR SHOWS A
WEAKENING TREND IN CONVECTION ACROSS EASTERN MONTANA AS MID LEVEL
LAPSE RATES REMAIN WEAK TO MARGINAL. HOWEVER...AN AREA OF THUNDERSTORMS
ARE HOLDING TOGETHER OVER NORTHEASTERN MONTANA WHERE BETTER LIFT
IS OCCURRING ASSOCIATED WITH THE LEFT FRONT EXIT REGION OF A JET
STREAK. BETTER MID LEVEL LAPSE RATES PER SPC MESOSCALE ANALYSIS
SHOULD ALLOW THIS AREA TO HOLD TOGETHER. THIS AREA OF PRECIPITATION
AND LIFT IS FORECAST TO ENTER OUR NORTHEASTERN ZONES BY LATE AFTERNOON.
OTHERWISE THE HRRR SUGGESTS RENEWED CONVECTION TO INITIATE OVER
SOUTHEASTERN MONTANA AND ROTATE NORTHEAST INTO WESTERN/SOUTHWESTERN
NORTH DAKOTA BY AROUND 00Z MONDAY. CURRENT FORECAST HAS THE BIG
PICTURE WELL IN HAND...JUST MINOR TWEAKS TO HOURLY OBS AND SKY
GRIDS AS MENTIONED ABOVE.
UPDATE ISSUED AT 906 CDT SUN JUL 28 2013
LATEST SATELLITE IMAGERY SHOWS THE LEADING EDGE OF H7-H5 CLOUDS
NOW ENTERING WESTERN NORTH DAKOTA. REGIONAL RADAR SHOWS AREAS OF
SHOWERS AND THUNDERSTORMS IN EASTERN MONTANA...FROM GLASGOW SOUTH
TO MILES CITY...AND MOVING EAST WITH TIME. WATER VAPOR DEPICTS A
COUPLE OF SHORTWAVES SUPPORTING THE PRECIPITATION AREAS AS THEY
MOVE CLOSER TO OUR WESTERN BORDER THIS MORNING. H7-H5 RIDGE AXIS
NOW LOCATED FROM ESTEVAN SOUTH TO DICKINSON. THIS WILL SHIFT TO
AROUND SHERWOOD SOUTH TO BISMARCK BY 00Z MONDAY. STILL ON TRACK FOR
DRY AND WARMER WEATHER CENTRAL WITH PLENTY OF SUNSHINE TODAY.
THE LATEST HRRR SUGGESTS SOME SHOWERS JUST EDGING OVER OUR WESTERN
BORDER BETWEEN 18Z SUNDAY AND 00Z MONDAY...WHICH IS WHAT THE CURRENT
FORECAST ENTAILS. NAM/GFS SOUNDINGS MAINTAIN A FAIRLY SIGNIFICANT
CAP FOR KISN/KDIK THROUGH 00Z MONDAY...WHICH SUPPORTS THE BEST
THREAT OF THUNDERSTORMS THROUGH 00Z MONDAY WEST OF WILLISTON AND
DICKINSON. BETTER FORCING OCCURS TONIGHT AND MONDAY WHEN A FRONTAL
SYSTEM MOVES INTO WESTERN AND EVENTUALLY CENTRAL NORTH DAKOTA
MONDAY ALONG WITH A COUPLE OF JET STREAKS ENHANCING LIFT OVER THE
FRONTAL BOUNDARY TO BETTER SUPPORT SHOWERS/THUNDERSTORMS.
OTHER THAN ADJUSTING SKY GRIDS UPWARD ACROSS THE WEST A BIT BASED
ON CURRENT VISIBLE IMAGERY...LITTLE IF ANY OTHER ADJUSTMENTS WERE MADE
TO THE CURRENT GRIDDED FORECAST.
UPDATE
ISSUED AT 643 AM CDT SUN JUL 28 2013
ADJUSTED THE HOURLY SENSIBLE WEATHER GRIDS BASED ON CURRENT
OBS/TRENDS...OTHERWISE LITTLE CHANGE TO THE GOING FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 455 AM CDT SUN JUL 28 2013
SURFACE HIGH PRESSURE RIDGE AXIS THIS MORNING WAS THROUGH THE RED
RIVER VALLEY AND CONTINUED TO SLIDE SLOWLY EAST. RETURN FLOW
AROUND THE HIGH HAS CAUSED AN EAST TO SOUTHEAST FLOW TO BECOME
ESTABLISHED OVER THE FORECAST AREA.
MORNING TEMPERATURES AS OF THIS WRITING WERE VERY COOL...MAINLY
IN THE MID 40S...WITH DEW POINT TEMPERATURES IN THE LOWER 40S.
WILL EXPECT TEMPERATURES TO DROP ANOTHER 3 TO 5 DEGREES BY THE
TIME THE ENERGY BALANCE OF HEAT LOSS VERSUS HEAT GAIN IS REACHED
WITHIN AN HOUR AFTER SUNRISE.
WITH THE STRONG SUBSIDENCE EAST HALF WILL FORECAST SUNNY / CLEAR.
IN THE WEST...LOW PRESSURE WAS DEEPENING IN THE LEE OF THE MONTANA
ROCKIES. IT IS FORECAST TO PUSH EAST...REACHING THE DAKOTAS BORDER
AFTER NIGHTFALL TONIGHT. THE QUESTION IS WHETHER OR NOT SHOWERS OR
STORMS WILL MOVE INTO THE WEST THIS AFTERNOON. THE SOUTHEAST FLOW
WILL NOT BE ADVECTING IN ANY HIGHER DEW POINT AIR THAN WHAT IS
ALREADY IN PLACE OVER THE AREA...AT LEAST NOT UNTIL SUNDAY NIGHT
WHEN DEW POINTS RISE TO OR JUST ABOVE 50. SO...ALTHOUGH
INSTABILITY WILL BE INCREASING THIS AFTERNOON...IT WILL BE ONLY
SLOWLY DOING SO. AND...THERE IS SOME CONVECTIVE INHIBITION THAT
WILL NEED TO BE OVERCOME. FOR THOSE REASONS...HAVE CONFINED STORM
CHANCES TO THE MONTANA BORDER COUNTIES UNTIL SUNDAY NIGHT.
OVERNIGHT SUNDAY NIGHT THE STORMS SHOULD INCREASE IN COVERAGE AS
THEY SPREAD INTO THE CENTRAL PART OF THE STATE. THIS AS MID LEVEL
SUPPORT INCREASES.
AS FAR AS SEVERE WEATHER CHANCES...THE RISK IS FOR ISOLATED SEVERE
STORMS AT THE WORST.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 455 AM CDT SUN JUL 28 2013
MEDIUM TO LONG RANGE FORECAST MODELS HAVE TRENDED TO A MORE ACTIVE
WEATHER PATTERN ACROSS THE NORTHERN PLAINS THROUGH NEXT WEEK WITH
THE UPPER LEVEL JET STREAM EITHER ALOFT OR NEAR THE NORTHERN PLAINS
REGION. THIS WILL INTRODUCE A BIT MORE UNCERTAINTY AS FAR AS
TEMPERATURE AND PRECIPITATION FORECASTS WITH MODELS PROJECTING
SEVERAL SMALLER SCALE WAVES MOVING THROUGH THE QUASI-ZONAL FLOW OVER
THE REGION.
ONGOING PRECIPITATION EXPECTED MONDAY MORNING WEST INTO CENTRAL WITH
A SURFACE TROUGH PUSHING EAST ACROSS THE DAKOTAS. SEVERE WEATHER
REMAINS QUESTIONABLE WITH LIMITED LOW LEVEL MOISTURE EAST AND A GOOD
POSSIBILITY OF EXTENSIVE CLOUDINESS PREVENTING SURFACE BASED
INSTABILITY/STORMS IN THE AFTERNOON/EVENING. AS THE SFC TROUGH AND
ASSOCIATED MID LEVEL S/WV MOVE OFF TO THE EAST...WILL SEE
SHOWERS/THUNDERSTORMS END FROM WEST TO EAST MONDAY EVENING/EARLY
TUESDAY MORNING.
MODELS HAVE TRENDED WETTER FOR TUESDAY...ESPECIALLY SOUTH...AS A MID
LEVEL TROUGH SWINGS EAST ACROSS FAR SOUTH CENTRAL CANADA ALONG WITH
A LINGERING SFC BOUNDARY ALONG TO SOUTH OF INTERSTATE 94. ENOUGH
INSTABILITY PRESENT TO SUPPORT STRONGER THUNDERSTORMS DURING THE
AFTERNOON/EVENING.
AFTER THIS PERIOD OF ACTIVE WEATHER...MODELS FORECAST A RETURN TO A
QUIETER WEATHER PERIOD LATER TUESDAY NIGHT THROUGH WEDNESDAY WITH
NORTHWEST FLOW ALOFT REDEVELOPING. AFTERWARDS MODELS DIVERGE
REGARDING THE MID LEVEL FLOW PATTERN SO WILL MAINTAIN FORECAST
CONSISTENCY FOR NOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1205 PM CDT SUN JUL 28 2013
MID/HIGH CLOUDS WILL CONTINUE TO INCREASE THROUGH 00Z MONDAY AND
BEGIN TO LOWER THEREAFTER...BUT REMAIN VFR. THIS IS IN ADVANCE OF
AN INCREASED THREAT FOR SCATTERED SHOWERS AND THUNDERSTORMS
BEGINNING LATE THIS AFTERNOON IN FAR WESTERN NORTH DAKOTA...THEN
ADVANCING INTO CENTRAL NORTH DAKOTA TOWARD 12Z MONDAY. A CHANCE
FOR THUNDERSTORMS WILL CONTINUE DURING THE DAY MONDAY. LOWEST
CEILINGS ARE FORECAST AROUND 4000FT AGL NEXT 24HR. VFR VISIBILITIES
ARE FORECAST BUT BRIEF MVFR VSBYS ARE POSSIBLE WITH ANY HEAVIER
SHOWERS OR THUNDERSTORMS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...JPM
LONG TERM...NH
AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
907 AM CDT SUN JUL 28 2013
.UPDATE...
ISSUED AT 906 CDT SUN JUL 28 2013
LATEST SATELLITE IMAGERY SHOWS THE LEADING EDGE OF H7-H5 CLOUDS
NOW ENTERING WESTERN NORTH DAKOTA. REGIONAL RADAR SHOWS AREAS OF
SHOWERS AND THUNDERSTORMS IN EASTERN MONTANA...FROM GLASGOW SOUTH
TO MILES CITY...AND MOVING EAST WITH TIME. WATER VAPOR DEPICTS A
COUPLE OF SHORTWAVES SUPPORTING THE PRECIPITATION AREAS AS THEY
MOVE CLOSER TO OUR WESTERN BORDER THIS MORNING. H7-H5 RIDGE AXIS
NOW LOCATED FROM ESTEVAN SOUTH TO DICKINSON. THIS WILL SHIFT TO
AROUND SHERWOOD SOUTH TO BISMARCK BY 00Z MONDAY. STILL ON TRACK FOR
DRY AND WARMER WEATHER CENTRAL WITH PLENTY OF SUNSHINE TODAY.
THE LATEST HRRR SUGGESTS SOME SHOWERS JUST EDGING OVER OUR WESTERN
BORDER BETWEEN 18Z SUNDAY AND 00Z MONDAY...WHICH IS WHAT THE CURRENT
FORECAST ENTAILS. NAM/GFS SOUNDINGS MAINTAIN A FAIRLY SIGNIFICANT
CAP FOR KISN/KDIK THROUGH 00Z MONDAY...WHICH SUPPORTS THE BEST
THREAT OF THUNDERSTORMS THROUGH 00Z MONDAY WEST OF WILLISTON AND
DICKINSON. BETTER FORCING OCCURS TONIGHT AND MONDAY WHEN A FRONTAL
SYSTEM MOVES INTO WESTERN AND EVENTUALLY CENTRAL NORTH DAKOTA
MONDAY ALONG WITH A COUPLE OF JET STREAKS ENHANCING LIFT OVER THE
FRONTAL BOUNDARY TO BETTER SUPPORT SHOWERS/THUNDERSTORMS.
OTHER THAN ADJUSTING SKY GRIDS UPWARD ACROSS THE WEST A BIT BASED
ON CURRENT VISIBLE IMAGERY...LITTLE IF ANY OTHER ADJUSTMENTS WERE MADE
TO THE CURRENT GRIDDED FORECAST.
UPDATE
ISSUED AT 643 AM CDT SUN JUL 28 2013
ADJUSTED THE HOURLY SENSIBLE WEATHER GRIDS BASED ON CURRENT
OBS/TRENDS...OTHERWISE LITTLE CHANGE TO THE GOING FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 455 AM CDT SUN JUL 28 2013
SURFACE HIGH PRESSURE RIDGE AXIS THIS MORNING WAS THROUGH THE RED
RIVER VALLEY AND CONTINUED TO SLIDE SLOWLY EAST. RETURN FLOW
AROUND THE HIGH HAS CAUSED AN EAST TO SOUTHEAST FLOW TO BECOME
ESTABLISHED OVER THE FORECAST AREA.
MORNING TEMPERATURES AS OF THIS WRITING WERE VERY COOL...MAINLY
IN THE MID 40S...WITH DEW POINT TEMPERATURES IN THE LOWER 40S.
WILL EXPECT TEMPERATURES TO DROP ANOTHER 3 TO 5 DEGREES BY THE
TIME THE ENERGY BALANCE OF HEAT LOSS VERSUS HEAT GAIN IS REACHED
WITHIN AN HOUR AFTER SUNRISE.
WITH THE STRONG SUBSIDENCE EAST HALF WILL FORECAST SUNNY / CLEAR.
IN THE WEST...LOW PRESSURE WAS DEEPENING IN THE LEE OF THE MONTANA
ROCKIES. IT IS FORECAST TO PUSH EAST...REACHING THE DAKOTAS BORDER
AFTER NIGHTFALL TONIGHT. THE QUESTION IS WHETHER OR NOT SHOWERS OR
STORMS WILL MOVE INTO THE WEST THIS AFTERNOON. THE SOUTHEAST FLOW
WILL NOT BE ADVECTING IN ANY HIGHER DEW POINT AIR THAN WHAT IS
ALREADY IN PLACE OVER THE AREA...AT LEAST NOT UNTIL SUNDAY NIGHT
WHEN DEW POINTS RISE TO OR JUST ABOVE 50. SO...ALTHOUGH
INSTABILITY WILL BE INCREASING THIS AFTERNOON...IT WILL BE ONLY
SLOWLY DOING SO. AND...THERE IS SOME CONVECTIVE INHIBITION THAT
WILL NEED TO BE OVERCOME. FOR THOSE REASONS...HAVE CONFINED STORM
CHANCES TO THE MONTANA BORDER COUNTIES UNTIL SUNDAY NIGHT.
OVERNIGHT SUNDAY NIGHT THE STORMS SHOULD INCREASE IN COVERAGE AS
THEY SPREAD INTO THE CENTRAL PART OF THE STATE. THIS AS MID LEVEL
SUPPORT INCREASES.
AS FAR AS SEVERE WEATHER CHANCES...THE RISK IS FOR ISOLATED SEVERE
STORMS AT THE WORST.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 455 AM CDT SUN JUL 28 2013
MEDIUM TO LONG RANGE FORECAST MODELS HAVE TRENDED TO A MORE ACTIVE
WEATHER PATTERN ACROSS THE NORTHERN PLAINS THROUGH NEXT WEEK WITH
THE UPPER LEVEL JET STREAM EITHER ALOFT OR NEAR THE NORTHERN PLAINS
REGION. THIS WILL INTRODUCE A BIT MORE UNCERTAINTY AS FAR AS
TEMPERATURE AND PRECIPITATION FORECASTS WITH MODELS PROJECTING
SEVERAL SMALLER SCALE WAVES MOVING THROUGH THE QUASI-ZONAL FLOW OVER
THE REGION.
ONGOING PRECIPITATION EXPECTED MONDAY MORNING WEST INTO CENTRAL WITH
A SURFACE TROUGH PUSHING EAST ACROSS THE DAKOTAS. SEVERE WEATHER
REMAINS QUESTIONABLE WITH LIMITED LOW LEVEL MOISTURE EAST AND A GOOD
POSSIBILITY OF EXTENSIVE CLOUDINESS PREVENTING SURFACE BASED
INSTABILITY/STORMS IN THE AFTERNOON/EVENING. AS THE SFC TROUGH AND
ASSOCIATED MID LEVEL S/WV MOVE OFF TO THE EAST...WILL SEE
SHOWERS/THUNDERSTORMS END FROM WEST TO EAST MONDAY EVENING/EARLY
TUESDAY MORNING.
MODELS HAVE TRENDED WETTER FOR TUESDAY...ESPECIALLY SOUTH...AS A MID
LEVEL TROUGH SWINGS EAST ACROSS FAR SOUTH CENTRAL CANADA ALONG WITH
A LINGERING SFC BOUNDARY ALONG TO SOUTH OF INTERSTATE 94. ENOUGH
INSTABILITY PRESENT TO SUPPORT STRONGER THUNDERSTORMS DURING THE
AFTERNOON/EVENING.
AFTER THIS PERIOD OF ACTIVE WEATHER...MODELS FORECAST A RETURN TO A
QUIETER WEATHER PERIOD LATER TUESDAY NIGHT THROUGH WEDNESDAY WITH
NORTHWEST FLOW ALOFT REDEVELOPING. AFTERWARDS MODELS DIVERGE
REGARDING THE MID LEVEL FLOW PATTERN SO WILL MAINTAIN FORECAST
CONSISTENCY FOR NOW.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 643 AM CDT SUN JUL 28 2013
PATCHY MORNING FOG OBSERVED AT KJMS...SHOULD BURN OFF BY 14Z.
HIGH PRESSURE RIDGE AXIS WILL BE MOVING THROUGH THE RED RIVER
VALLEY AND INTO MINNESOTA TODAY WITH SOUTHEAST FLOW DEVELOPING
BETWEEN IT AND LOW PRESSURE FORMING IN THE LEE OF THE MONTANA
ROCKIES. ISOLATED THUNDERSTORMS WILL FORM IN MONTANA AND COULD MOVE
INTO WESTERN NORTH DAKOTA AFTER 28/17Z. MORE WIDESPREAD STORMS ARE
FORECAST FOR THE PERIOD AFTER 29/00Z FOR KISN-KDIK...POSSIBLY
REACHING A KMOT-KBIS LINE AFTER 29/06Z.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...JPM
LONG TERM...NH
AVIATION...JPM
AREA FORECAST DISCUSSION
NWS TULSA OK
800 PM CDT MON JUL 29 2013
.DISCUSSION...
STORMS THAT DEVELOPED NEAR THE BORDER OVER SOUTHWEST KS AND
NORTHWEST OK ARE MOVING SOUTHEAST THIS EVENING INTO NORTHWEST AND
NORTH CENTRAL OK. SEVERAL RUNS OF THE HRRR MODEL HAVE BEEN
FORECASTING THE CONVECTION TO BUILD SOUTH INTO OKLAHOMA.
CONSOLIDATING COLD POOLS WILL PUSH INTO THE STRENGTHENING
SOUTHWESTERLY LLJ THIS EVENING...AND SHOULD HELP TO KEEP THE
STORMS GOING FOR SEVERAL MORE HOURS. DAMAGING WINDS 60-70 MPH AND
MARGINALLY SEVERE HAIL WILL BE THE MAIN THREATS...AND THIS THREAT
WILL BE GREATEST BEFORE MIDNIGHT AND TO THE WEST OF TULSA. THE
CURRENT FORECAST HAS HIGH POPS NEAR THE KS BORDER AND SEE NO
REASON TO CHANGE AT THIS POINT GIVEN LATEST HRRR DATA.
LACY
&&
.PREV DISCUSSION... /ISSUED 605 PM CDT MON JUL 29 2013/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
FOR THE 0Z TAFS... SCATTERED THUNDERSTORMS MAY AFFECT NORTHEAST
OKLAHOMA AND NORTHWEST ARKANSAS SITES THIS EVENING. LATER IN THE
EVENING AND OVERNIGHT PRESENTS THE GREATEST CHANCE FOR WIDESPREAD
CONVECTIVE ACTIVITY AT THESE SITES. ANY SITE EXPERIENCING A STORM
CELL WILL LIKELY SEE TEMPORARY MVFR CONDITIONS WITH STRONG GUSTY
WINDS AND HEAVY RAINFALL.
PREV DISCUSSION... /ISSUED 407 PM CDT MON JUL 29 2013/
DISCUSSION...
PRECIPITABLE WATER VALUES IN EXCESS OF TWO BUCKS
COUPLED WITH IMPENDING THUNDER WILL DEPOSIT LOTS
OF RAIN TONIGHT... ESPECIALLY FROM ABOUT HIGHWAY
412 NORTH. THUNDER THROUGH THE EVENING HOURS MAY
BE SEVERE WITH BIG HAIL & WIND. HIGH RES MODELS
BULLISH ON QPF AND PUSHING MCS CLUSTER SOUTHEAST
WHILE LOW RES MODELS LESS SO. LOCAL 3 INCH RAIN
NOT OUT OF THE QUESTION TONIGHT..ESPECIALLY NEAR
THE KANSAS BORDER. FLOOD WATCH AREA MAY NEED TO
BE STRETCHED SOUTHEAST... IF SHORT RANGE MODELS
VERIFY. CARRIED HIGHER POPS INTO TUESDAY MORNING
GIVEN MODEL BIAS OF LESS RAIN BEHIND MCS ACTION.
ALSO LOWERED MAX TEMPS TUESDAY NORTH. LESSER POP
TUESDAY AFTERNOON AND NIGHT WITH COOL FRONT.
DRY WEDNESDAY/THURSDAY EAST OF H5 RIDGE ANCHORED
SOUTHWEST. NEXT WAVE IN NORTHWEST FLOW OVER THE
RIDGE BRINGS RAIN CHANCES AGAIN FRIDAY/SATURDAY.
GW
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 73 91 75 92 / 80 50 20 10
FSM 75 94 74 93 / 50 40 10 10
MLC 73 96 74 94 / 40 20 20 10
BVO 72 89 70 88 / 90 60 20 10
FYV 72 87 70 89 / 70 60 20 10
BYV 69 86 71 87 / 70 70 20 10
MKO 72 90 73 92 / 60 40 20 10
MIO 71 87 72 88 / 100 70 20 10
F10 72 93 73 93 / 70 40 20 10
HHW 72 94 74 95 / 10 20 0 10
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...FLASH FLOOD WATCH UNTIL 1 PM TUESDAY FOR OKZ054-OKZ055-OKZ056-
OKZ057-OKZ059.
AR...NONE.
&&
$$
LONG TERM....30
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
129 AM EDT SUN JUL 28 2013
.SYNOPSIS...
A DEEP CLOSED LOW LOCATED OVER THE UPPER GREAT LAKES WILL MOVE
SLOWLY NORTHEAST INTO QUEBEC BY EARLY IN THE UPCOMING WEEK. AN
ASSOCIATED SURFACE LOW AND TRAILING COLD FRONT WILL MARCH EAST
FROM THE OHIO VALLEY TONIGHT...THEN TEMPORARILY STALL OUT ACROSS
CENTRAL PENNSYLVANIA ON SUNDAY. HIGH PRESSURE WILL RETURN TO THE
AREA BEHIND THE COLD FRONT...ACCOMPANIED BY ANOTHER SHOT OF COOL
CANADIAN AIR. THE COOL CONDITIONS WILL BE FOLLOWED BY A GRADUAL
MODERATION BACK TO NORMAL FOR LATE JULY AND EARLY AUGUST.
&&
.NEAR TERM /UNTIL 7 AM THIS MORNING/...
UPSTREAM RADAR TRENDS MIMIC THE RUC 1-2 HR PROGS AND WILL CONTINUE
HIGH POPS IN THE WRN AND NRN MTS. THE LOWER SUSQ ALSO IN LINE FOR
MORE SHOWERS AND OCCNL RUMBLES OF THUNDER. COLD FRONT IS NOT
MAKING TOO RAPID A MOVE THROUGH ERN OH. WEAK WAVE COMING UP FROM
WV WILL LIKELY SLOW IT TO A CRAWL AS HAS BEEN EXPECTED. THIS WILL
RESULT IN A CONTINUE CHC TO LIKLIHOOD OF SHOWERS THROUGH THE REST
OF THE NIGHT. LOW TEMPS WILL VARY FROM THE U50S ACROSS THE NW
MTNS TO THE MID AND UPPER 60S IN THE SUSQ VALLEY.
&&
.SHORT TERM /7 AM THIS MORNING THROUGH 6 PM MONDAY/...
12Z OPER MODELS AND ENSEMBLES INDICATE THAT THE CENTER OF A LARGE
MID-LEVEL CLOSED LOW WILL SHIFT TO THE NORTHEAST OF THE UPPER GREAT
LAKES REGION DURING THIS PERIOD. THE BEST MSTR AND INSTABILITY IS
PROGGED ALONG AND AHEAD OF THE EASTWARD CREEPING SFC COLD FRONT
/WHICH IS PROGGED TO BE OVER THE CENTRAL MTNS AND SUSQ VALLEY DURING
THE MIDDAY AND AFTERNOON HOURS SUNDAY.
BROAD SCALE UVVEL ASSOCIATED WITH A WELL-DEFINED UPR JET ENTRANCE
REGION /WITH THE CORE OF THE 100 KT 300 MB SSW-NNE JET LOCATED OVER
WRN NEW YORK AT 18Z SUNDAY/ WILL COMBINE WITH A MDTLY STG AND
COMPACT SPEED MAX HEADING NORTH UP THE MID ATLANTIC PIEDMONT AND TWD
THE SUSQ VALLEY...WILL BRING ANOTHER FEW ROUNDS OF SHOWERS AND SOME
EMBEDDED TSRA TO MAINLY THE ERN HALF OF THE CWA. ADDITIONAL 0.50
INCH AMTS AREA LIKELY ACROSS THE SUSQ VALLEY AND POINTS EAST DURING
THE DAY...WHILE A GRADIENT TO LIGHTER AMTS WILL OCCUR FURTHER WEST.
LOCALIZED 1 INCH AMTS POSSIBLE ACROSS OUR ERN ZONES WHERE A FEW
TRAINING TSRA OCCUR.
MAXES SUNDAY WILL BE A FEW TO SVRL DEG F COOLER THAN SATURDAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
SIGNIFICANT POST-FRONTAL DRYING WILL SPREAD WEST TO EAST ACRS THE
ERN SLOPES OF THE APPLCHNS INTO THE PIEDMONT SUN NGT INTO MON. 12Z
MODELS INDICATE FRONTAL WAVE DEVELOPMENT ALONG THE BOUNDARY IN THE
LEE OF THE APPLCHNS LATE SUNDAY...OVERNIGHT INTO MONDAY...WHICH
COULD LEAD TO SOME ORGANIZED THUNDERSTORMS AND ENHANCED RAINFALL.
THE UPPER LOW WILL MOVE THROUGH THE REGION ON MONDAY...AND MAY
BRING A FEW SHOWERS TO THE NW MTNS UNDER COOL POCKET ALOFT.
UNSEASONABLY COOL CONDITIONS ARE EXPECTED THRU THE PERIOD WITH
TEMPERATURES RUNNING 5 TO AS MUCH AS 10-12 DEGREES BELOW LATE JULY
CLIMO MAXES.
ALL MEDIUM RANGE MODEL AND ENSEMBLE DATA SHOW AN ACTIVE AND
BROADENING UPPER TROUGH OVER THE UPPER MIDWEST/GREAT LAKES/NORTHEAST
HEADING INTO THE FIRST WEEK OF AUGUST. THE LARGE UPPER LEVEL LOW
WILL BE MOVE NORTHEASTWARD BY MID WEEK. A ZONAL PATTER WILL FOLLOW
WITH DRIER AIR AND HIGH PRESSURE SHOULD PROVIDE FAIR/DRY WEATHER TUE-
WED WITH A PERIOD OF UNSETTLED WEATHER DURING THE SECOND HALF OF
NEXT WEEK. TEMPS SHOULD TREND CLOSER TO NORMAL...WITH NO
SIGNIFICANT HEAT/HUMIDITY ON THE HORIZON.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AN APPROACHING COLD FRONT AND SURGE OF MOISTURE WILL PRODUCE A FEW
ADDITIONAL SHOWERS ACROSS CENTRAL PA OVERNIGHT. EARLIER THUNDERSTORMS
HAVE PUSHED EAST OF THE AREA AND THE THREAT OF ADDITIONAL TSRA
OVERNIGHT IS LOW. AS OF 03Z...MOST LOCATIONS REPORTING EITHER VFR
OR MVFR. HOWEVER...A CONTINUED MOIST SOUTHERLY FLOW ASCENDING THE
HIGH TERRAIN OF NORTHERN PA MAY RESULT IN IFR CIGS AT BFD LATER
TONIGHT. A WIND SHIFT TO THE SW COULD POTENTIALLY CAUSE SIMILAR
UPSLOPE-INDUCED LOW CIGS AT JST TOWARD DAWN. HOWEVER...CONFIDENCE
NOT AS HIGH AS FOR BFD.
ELSEWHERE...MVFR CIGS ARE POSSIBLE OVERNIGHT...AS BLYR COOLS/MOISTENS.
SOME THIN SPOTS IN THE OVERCAST NOTED IN SATL IMAGERY ACROSS
WESTERN PA AT 03Z. IF THOSE BREAKS PERSIST...RADIATIONAL COOLING
COULD POTENTIALLY RESULT IN A BRIEF DIP TO IFR VSBYS NR DAWN IN
THE RIDGE VALLEY REGION FROM AOO NE THRU UNV AND IPT.
THE SLOW-MOVING COLD FRONT WILL PUSH THROUGH THE W MTNS BY LATE
SUNDAY MORNING...BUT TAKE UNTIL LATE IN THE DAY TO CLEAR THE
EASTERN AIRFIELDS ACROSS THE SUSQ VALLEY. ANY EARLY LOW CIGS/FOG
SHOULD LIFT BY LATE AM WITH WIDESPREAD VFR CONDS LIKELY BY AFTN.
THE MAIN AVIATION CONCERN SUNDAY WILL BE FOR THE POTENTIAL OF PM
TSRA DEVELOPING ALONG COLD FRONT OVR EASTERN PA...WHICH COULD
POTENTIALLY AFFECT MDT OR LNS.
OUTLOOK...
MON...PATCHY PRE-DAWN FOG POSSIBLE.
TUE...AM FOG POSSIBLE NW MTNS.
WED...NO SIG WX EXPECTED.
THU...AM LOW CIGS POSS CENTRAL MTNS. SCT PM TSRA IMPACTS POSS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...DANGELO/LA CORTE
SHORT TERM...LAMBERT/STEINBUGL
LONG TERM...CERU/STEINBUGL
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1246 PM CDT SUN JUL 28 2013
.DISCUSSION...
SEE THE 18Z AVIATION DISCUSSION BELOW.
40
&&
.AVIATION...
THE WEAK SURFACE BOUNDARY HAS SLOWLY LIFTED TO NEAR KCLL AND KUTS
AT 1730Z. MODEL SOUNDING FORECASTS SHOW CAPE VALUES REACHING TO
BETWEEN 2500 AND 3000 THIS AFTERNOON. WITH OUTFLOW BOUNDARIES AND
THE SEA/BAY BREEZE LIKELY INTERSECTING THIS AFTERNOON...LIKED THE
HIGH RESOLUTION MODEL SOLUTIONS. THE HRRR IN PARTICULAR ENDS THE
SHOWER AND THUNDERSTORM CHANCES DURING LATE AFTERNOON AND TRIED TO
TIME THE FORECASTS WITH THIS MODEL. THE NAM12 DOES FORECAST
CHANCES FOR MVFR OVERNIGHT TONIGHT. EXPECT IF MVFR DOES DEVELOP
THAT THE CEILINGS WILL LIFT DURING THE MID AND LATE MORNING PERIOD
ON MONDAY.
40
&&
.PREV DISCUSSION... /ISSUED 1010 AM CDT SUN JUL 28 2013/
DISCUSSION...
BASED ON DEWPOINTS IT APPEARS DIFFUSE BOUNDARY IS SITUATED FROM
ROUGHLY BRENHAM TO GALVESTON BAY. DEWPOINTS IN THE LOWER 70S NE OF
THAT LINE AND NEAR 80 FURTHER SW (DOG BREATH CONDITIONS). SCT
SHRA/TSRA CONTINUE DEVELOPING AND WILL MAINTAIN CHANCE POPS FOR
THE REMAINDER OF THE DAY. ANTICIPATE ACTIVITY WILL PROBABLY FOCUS
FURTHER INLAND AS THE MORNING AND AFTERNOON PROGRESSES. 47
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 94 76 97 75 99 / 30 10 10 10 10
HOUSTON (IAH) 94 76 95 76 97 / 30 10 10 10 10
GALVESTON (GLS) 91 81 90 81 90 / 30 10 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...47
AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1153 PM CDT SAT JUL 27 2013
.DISCUSSION...
SEE AVIATION SECTION BELOW FOR 06Z TAF DISCUSSION.
&&
.AVIATION...
LEFTOVER BOUNDARIES ACROSS SOUTHEAST TEXAS FROM SATURDAY`S SHRA/TSRA
MIGHT BECOME A FOCUS FOR DEVELOPMENT DURING THE OVERNIGHT HOURS. NOT
VERY CONFIDENT WHETHER OR NOT THIS WILL HAPPEN...BUT THE LATEST AVAILABLE
RAP13 AND HRRR RUNS BOTH INDICATE THEIR FORMATION BEFORE SUNRISE. COULD
SEE SOME MVFR CEILINGS DEVELOP TOO. STILL THINK THE AREA WILL SEE SOME
SHRA/TSRA DEVELOPMENT DURING THE DAY ON SUNDAY...BUT DO NOT EXPECT AS
MUCH ACTIVITY AS WAS SEEN ON SATURDAY. 42
&&
.PREV DISCUSSION... /ISSUED 934 PM CDT SAT JUL 27 2013/
UPDATE...
SCATTERED CONVECTION CONTINUES THIS EVENING GENERALLY ALONG THE
INTERSTATE 10 CORRIDOR AROUND THE HOUSTON METRO AREA. MODELS ALL
IN FAIRLY GOOD AGREEMENT WITH AT LEAST ISOLATED ACTIVITY
PERSISTING THROUGH THE OVERNIGHT HOURS SO HAVE KEPT POPS IN PLACE
FOR THE SOUTHERN HALF OF THE REGION OVERNIGHT. 38
PREV DISCUSSION... /ISSUED 248 PM CDT SAT JUL 27 2013/
DISCUSSION...
BKN THIN BAND OF SHRA/TSRA DEVELOPING ALONG WEAK FRONTAL BOUNDARY
FROM ROUGHLY MOSS HILL-HOUSTON-EAGLE LAKES. SUSPECT THIS WILL
PROBABLY KEEP GOING INTO THE EVENING HOURS WITH PERHAPS SOME
PERIODS OF ENHANCEMENT BETWEEN I-10 & THE COAST WHERE A GOOD LLVL
CONVERGENT ZONE & HEATING CONTINUES. WOULDN`T BE SURPRISED TO SEE
A SLOW MOVING CELL THROW DOWN A VERY LOCALIZED FEW INCHES OF
RAINFALL BETWEEN NOW AND SUNSET SOMEWHERE WITHIN THIS CORRIDOR.
EXPECT PRECIP COVERAGE TO DIMINISH WITH LOSS OF HEATING...BUT
PROBABLY FLARE BACK UP AFTER 2 AM NEAR OR JUST OFF THE COAST.
REMNANTS OF THE BOUNDARY SHOULD PUSH BACK NORTH AND WASH OUT THRU
THE DAY SUNDAY. SUNDAY SHOULD BE THE LAST DAY OF MENTIONABLE POPS
AT LEAST UNTIL NEXT WEEKEND IF NOT LONGER. UPPER RIDGE WILL TAKE
BACK CONTROL AND PERSIST THRU THE WEEK. THICKNESS VALUES DO RISE A
TOUCH BUT LLVL FLOW SHOULD MOSTLY BE OUT OF THE SOUTH VERSUS THE
HOTTER SW. KNOCKED A FEW DEGREES OFF AFTN HIGHS IN THE MID/LONG
RANGE PERIOD BUT PROBABLY NOT ENOUGH TO REQUIRE A JACKET... 47
MARINE...
THE WINDS OFF THE COAST MAY PICK UP AGAIN TONIGHT...ALTHOUGH WITH A
WEAK FRONTAL BOUNDARY APPROACHING THE COAST FROM THE NORTHWEST THE
WIND SPEEDS WILL MORE LIKELY DIMINISH A BIT. DO EXPECT THE WINDS TO
STAY BELOW CAUTION CRITERIA. OTHERWISE...ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE THROUGH SUNDAY MORNING.
THE NAM12 SOUNDING FORECASTS ALONG THE COAST INDICATE THAT ISOLATED
STORMS ARE POSSIBLE. THE HIGHER RESOLUTION MODELS ARE
FORECASTING AN END TO ANY THUNDERSTORM CHANCES LATER ON SUNDAY. HIGH
PRESSURE WILL THEN BUILD IN OVERHEAD...ENDING RAIN CHANCES FOR MOST
OF THE WEEK. 40
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 75 95 76 97 76 / 10 20 10 10 10
HOUSTON (IAH) 76 94 77 95 77 / 20 30 10 10 10
GALVESTON (GLS) 81 90 81 90 81 / 40 30 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...38
AVIATION/MARINE...42
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
619 AM EDT SUN JUL 28 2013
.SYNOPSIS...
A COLD FRONT WILL PASS THROUGH THE REGION TODAY. HIGH PRESSURE
WILL BRING DRIER AND COOLER AIR TO THE REGION FOR MONDAY AND
TUESDAY. AN AREA OF LOW PRESSURE ARRIVES FROM THE WEST ON
WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 615 AM EDT SUNDAY...
COLD FRONT EXTENDED FROM LAKE ERIE TO CENTRAL TENNESSEE. SURFACE
DEW POINTS DROP INTO THE UPPER 40S TO MID 50S BEHIND THE FRONT.
SHOWERS AND THUNDERSTORMS WERE ISOLATED TO SCATTERED ALONG AND
AHEAD OF THE FRONT...THAT WAS JUST ENTERING THE WESTERN COUNTY
WARNING AREA. FLASH FLOOD WATCH HAS EXPIRED. THE TREAT OF HEAVY
RAIN HAS DIMINISHED.
MODELS WERE SIMILAR WITH THE TIMING OF THE FRONT AS ASSOCIATED
PRECIPITATION...WITH THE BOUNDARY REACHING THE BLUE RIDGE BY
18Z/2PM AND EXITING THE FORECAST AREA AROUND 00Z/8PM. STILL
POSSIBLE FOR REDEVELOPMENT AND BETTER AREAL COVERAGE OF SHOWERS
AND THUNDERSTORMS THIS AFTERNOON EAST OF THE BLUE RIDGE. LIMITED
INSTABILITY AND SHEAR WILL KEEP ANY SEVERE THREAT LOCALIZED.
MUCH DRIER AIR REACHES THE FORECAST AREA TONIGHT. AFTER SOME
UPSLOPE CLOUDS IN SOUTHEAST WEST VIRGINIA THIS EVENING...HAVE
MUCH OF THE COUNTY WARNING AREA CLEARING OUT BY MORNING.
PIEDMONT WILL BE AHEAD OF THE FRONT MUCH OF THE DAY AND WITH ANY
SUNSHINE WILL BE ABLE TO GET INTO THE 80S FOR MAXIMUM
TEMPERATURES. USED A BLEND OF MOS GUIDANCE AND BIAS CORRECTED MAV
NUMBERS FOR MINIMUM TEMPERATURES TONIGHT.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 400 AM EDT SUNDAY...
CLOSED LOW OVER THE GREAT LAKES WILL GRADUALLY MOVE NORTHEAST INTO
SOUTHEASTERN CANADA AND WEAKEN BY TUESDAY NIGHT. THE UPPER TROUGH
WILL FLATTEN RESULTING IN A FASTER MORE ZONAL FLOW FOR OUR REGION.
SFC HIGH PRESSURE WILL BUILD EAST ACROSS OUR AREA PROVIDING A COOLER
AND DRIER AIRMASS FOR MONDAY INTO TUESDAY. AN UPPER DISTURBANCE WILL
TRY AND SPREAD MOISTURE BACK INTO THE WEST AND SOUTHWEST ON TUESDAY
NIGHT. IN GENERAL...LEANED TEMPERATURES TOWARDS THE ADJMAVBC DURING
THE PERIOD. HIGHS WILL VARY FROM THE LOWER 70S IN THE MOUNTAINS TO
THE MID 80S IN THE SOUTHEAST. LOWS MONDAY NIGHT WILL RANGE FROM THE
UPPER 40S IN THE NORTHWEST MOUNTAINS TO THE LOWER 60S IN THE
PIEDMONT. WITH INCREASED CLOUD COVER LOW TEMPERATURES TUESDAY NIGHT
WILL MODERATE TO THE UPPER 50S IN THE WEST TO THE UPPER 60S IN THE
SOUTHEAST.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 400 PM EDT FRIDAY...
ALTHOUGH THE OP GFS HAS BACKED OFF...THE GEFS AND ECMWF RATHER
BULLISH WITH REGARDS TO WIDESPREAD STRATIFORM RAIN AND POSSIBLY EVEN
AN INSITU WEDGE FOR WEDNESDAY. WITH SURFACE WINDS STILL SHOWING SOME
SOUTHERLY COMPONENT...HESITANT TO GO AS COLD AS AN IN SITU WEDGE
WOULD SUGGEST. HOWEVER...FELT IT WAS PRUDENT TO GO COLDER THAN
GUIDANCE/HPC AT THIS TIME AND PLACE TEMPS RIGHT IN THE MIDDLE OF THE
2M TEMPS AND ECMWF MOS. AN IN SITU WEDGE AND ALL DAY RAIN COULD
EASILY KEEP TEMPS IN THE LOW 70S FOR THE ENTIRE DAY. ONCE THAT
SYSTEM DEPARTS...DEVELOPING REX BLOCK IN THE PAC NW WILL FORCE A
SLICE OF THE FOUR CORNERS UPPER RIDGE AND +20C H85 AIR TO DART INTO
OUR REGION LATE NEXT WEEK. THUS...EXPECTING ISOLATED STORMS IN THE
MOUNTAINS TO END THE FORECAST.
&&
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
AS OF 150 AM EDT SUNDAY...
ALTHOUGH THICK CLOUD COVER IS IN PLACE...PLENTIFUL RAIN AND ENOUGH
LOW LEVEL MOISTURE FOR IFR CEILINGS AND VISIBILITIES AT
BCB/LWB/ROA EARLY THIS MORNING. RADAR CONTINUED TO SHOW ISOLATED
SHOWERS NEAR BLF AND BCB.
A MORE ORGANIZED LINE OF SHOWERS AND THUNDERSTORMS WITH HEAVY RAIN
WILL APPROACH THE AREA EARLY THIS MORNING. LATEST HRRR GUIDANCE
SUGGESTS THIS BAND OF PRECIPITATION WILL REACH BLF AND LWB AROUND
09Z/5AM...BUT CONFIDENCE IN THIS TIMING IS LOW.
A COLD FRONT CROSSES THE AREA THIS AFTERNOON INTO THE EVENING...
AND WILL CONTINUE THE SHOWERS AND STORMS DURING THE DAY.
HIGH PRESSURE WILL BUILD INTO THE REGION BY MONDAY...AND INFLUENCE
OUR WEATHER PATTERN THROUGH TUESDAY. MAINLY VFR CONDITIONS ARE
EXPECTED THROUGH THIS TIME PERIOD WITH LATE NIGHT AND EARLY
MORNING MOUNTAIN AND VALLEY FOG POSSIBLE.
ON WEDNESDAY... AN AREA OF LOW PRESSURE WILL APPROACH AND MOVE
INTO THE AREA. EXPECT A RETURN OF ORGANIZED PRECIPITATION AND
AREAS OF SUB-VFR CONDITIONS AS EARLY AS LATE TUESDAY NIGHT ACROSS
THE WEST.
BY THURSDAY...AN UPPER RIDGE STRETCHES EAST WITH MOUNTAIN
THUNDERSTORMS EXPECTED DURING THE AFTERNOON.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...KK
LONG TERM...KM
AVIATION...AMS/KM
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
426 AM EDT SUN JUL 28 2013
.SYNOPSIS...
A COLD FRONT WILL PASS THROUGH THE REGION TODAY. HIGH PRESSURE
WILL BRING DRIER AND COOLER AIR TO THE REGION FOR MONDAY AND
TUESDAY. AN AREA OF LOW PRESSURE ARRIVES FROM THE WEST ON
WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 415 AM EDT SUNDAY...
COLD FRONT EXTENDED FROM LAKE ERIE TO CENTRAL TENNESSEE. SURFACE
DEW POINTS DROP INTO THE UPPER 40S TO MID 50S BEHIND THE FRONT.
A NARROW BAND OF SHOWERS AND THUNDERSTORMS ALONG THE FRONT WAS
JUST ENTERING THE WESTERN COUNTY WARNING AREA.ISOLATED SHOWERS
WERE OVER THE NEW RIVER VALLEY INTO NORTHWEST NORTH CAROLINA.
MODELS WERE SIMILAR WITH THE TIMING OF THE FRONT AS ASSOCIATED
PRECIPITATION...WITH THE BOUNDARY REACHING THE BLUE RIDGE BY
18Z/2PM AND EXITING THE FORECAST AREA AROUND 00Z/8PM. STILL
POSSIBLE FOR REDEVELOPMENT AND BETTER AREAL COVERAGE OF SHOWERS
AND THUNDERSTORMS THIS AFTERNOON EAST OF THE BLUE RIDGE. LIMITED
INSTABILITY AND SHEAR WILL KEEP ANY SEVERE THREAT LOCALIZED.
MUCH DRIER AIR REACHES THE FORECAST AREA TONIGHT. AFTER SOME
UPSLOPE CLOUDS IN SOUTHEAST WEST VIRGINIA THIS EVENING...HAVE
MUCH OF THE COUNTY WARNING AREA CLEARING OUT BY MORNING.
PIEDMONT WILL BE AHEAD OF THE FRONT MUCH OF THE DAY AND WITH ANY
SUNSHINE WILL BE ABLE TO GET INTO THE 80S FOR MAXIMUM
TEMPERATURES. USED A BLEND OF MOS GUIDANCE AND BIAS CORRECTED MAV
NUMBERS FOR MINIMUM TEMPERATURES TONIGHT.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 400 AM EDT SUNDAY...
CLOSED LOW OVER THE GREAT LAKES WILL GRADUALLY MOVE NORTHEAST INTO
SOUTHEASTERN CANADA AND WEAKEN BY TUESDAY NIGHT. THE UPPER TROUGH
WILL FLATTEN RESULTING IN A FASTER MORE ZONAL FLOW FOR OUR REGION.
SFC HIGH PRESSURE WILL BUILD EAST ACROSS OUR AREA PROVIDING A COOLER
AND DRIER AIRMASS FOR MONDAY INTO TUESDAY. AN UPPER DISTURBANCE WILL
TRY AND SPREAD MOISTURE BACK INTO THE WEST AND SOUTHWEST ON TUESDAY
NIGHT. IN GENERAL...LEANED TEMPERATURES TOWARDS THE ADJMAVBC DURING
THE PERIOD. HIGHS WILL VARY FROM THE LOWER 70S IN THE MOUNTAINS TO
THE MID 80S IN THE SOUTHEAST. LOWS MONDAY NIGHT WILL RANGE FROM THE
UPPER 40S IN THE NORTHWEST MOUNTAINS TO THE LOWER 60S IN THE
PIEDMONT. WITH INCREASED CLOUD COVER LOW TEMPERATURES TUESDAY NIGHT
WILL MODERATE TO THE UPPER 50S IN THE WEST TO THE UPPER 60S IN THE
SOUTHEAST.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 400 PM EDT FRIDAY...
ALTHOUGH THE OP GFS HAS BACKED OFF...THE GEFS AND ECMWF RATHER
BULLISH WITH REGARDS TO WIDESPREAD STRATIFORM RAIN AND POSSIBLY EVEN
AN INSITU WEDGE FOR WEDNESDAY. WITH SURFACE WINDS STILL SHOWING SOME
SOUTHERLY COMPONENT...HESITANT TO GO AS COLD AS AN IN SITU WEDGE
WOULD SUGGEST. HOWEVER...FELT IT WAS PRUDENT TO GO COLDER THAN
GUIDANCE/HPC AT THIS TIME AND PLACE TEMPS RIGHT IN THE MIDDLE OF THE
2M TEMPS AND ECMWF MOS. AN IN SITU WEDGE AND ALL DAY RAIN COULD
EASILY KEEP TEMPS IN THE LOW 70S FOR THE ENTIRE DAY. ONCE THAT
SYSTEM DEPARTS...DEVELOPING REX BLOCK IN THE PAC NW WILL FORCE A
SLICE OF THE FOUR CORNERS UPPER RIDGE AND +20C H85 AIR TO DART INTO
OUR REGION LATE NEXT WEEK. THUS...EXPECTING ISOLATED STORMS IN THE
MOUNTAINS TO END THE FORECAST.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
AS OF 150 AM EDT SUNDAY...
ALTHOUGH THICK CLOUD COVER IS IN PLACE...PLENTIFUL RAIN AND ENOUGH
LOW LEVEL MOISTURE FOR IFR CEILINGS AND VISIBILITIES AT
BCB/LWB/ROA EARLY THIS MORNING. RADAR CONTINUED TO SHOW ISOLATED
SHOWERS NEAR BLF AND BCB.
A MORE ORGANIZED LINE OF SHOWERS AND THUNDERSTORMS WITH HEAVY RAIN
WILL APPROACH THE AREA EARLY THIS MORNING. LATEST HRRR GUIDANCE
SUGGESTS THIS BAND OF PRECIPITATION WILL REACH BLF AND LWB AROUND
09Z/5AM...BUT CONFIDENCE IN THIS TIMING IS LOW.
A COLD FRONT CROSSES THE AREA THIS AFTERNOON INTO THE EVENING...
AND WILL CONTINUE THE SHOWERS AND STORMS DURING THE DAY.
HIGH PRESSURE WILL BUILD INTO THE REGION BY MONDAY...AND INFLUENCE
OUR WEATHER PATTERN THROUGH TUESDAY. MAINLY VFR CONDITIONS ARE
EXPECTED THROUGH THIS TIME PERIOD WITH LATE NIGHT AND EARLY
MORNING MOUNTAIN AND VALLEY FOG POSSIBLE.
ON WEDNESDAY... AN AREA OF LOW PRESSURE WILL APPROACH AND MOVE
INTO THE AREA. EXPECT A RETURN OF ORGANIZED PRECIPITATION AND
AREAS OF SUB-VFR CONDITIONS AS EARLY AS LATE TUESDAY NIGHT ACROSS
THE WEST.
BY THURSDAY...AN UPPER RIDGE STRETCHES EAST WITH MOUNTAIN
THUNDERSTORMS EXPECTED DURING THE AFTERNOON.
&&
.HYDROLOGY...
AS OF 420 AM EDT SUNDAY...
BEST CHANCE OF HEAVY RAIN WILL BE EAST OF THE BLUE RIDGE THIS
AFTERNOON AND EVEN THAT WILL BE LOCALIZED.
WILL KEEP CURRENT FLASH FLOOD WATCH VALID UNTIL 6AM. ONCE THE FRONT
CROSSES THROUGH THE REGION WHERE THERE HAS BEEN RECENT FLOODING
AND THE GROUND IS COMPLETELY SATURATED...THE CHANCE OF RAIN WILL
BE GREATLY REDUCED AND THE FLASH FLOOD WATCH WILL BE CANCELED.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLASH FLOOD WATCH UNTIL 6 AM EDT EARLY THIS MORNING FOR VAZ015-
016.
NC...FLASH FLOOD WATCH UNTIL 6 AM EDT EARLY THIS MORNING FOR
NCZ001>003-018>020.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...KK
LONG TERM...KM
AVIATION...AMS/KM
HYDROLOGY...AMS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
151 AM EDT SUN JUL 28 2013
.SYNOPSIS...
A COLD FRONT APPROACHES LATE TONIGHT...CROSSING THE REGION
TOMORROW. HIGH PRESSURE WILL BRING DRIER AIR TO THE REGION EARLY
NEXT WEEK. AN AREA OF LOW PRESSURE ARRIVES FROM THE WEST ON
WEDNESDAY. AN UPPER RIDGE BUILDS EAST LATE IN THE WORK WEEK.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
AS OF 1200 AM EDT SATURDAY...
WITH FRONT TO OUR WEST THIS MORNING AND NO REAL CHANGE IN AIRMASS
ELECTED TO EXTENDED FLASH FLOOD WATCH UNTIL 6 AM ALONG THE
SOUTHERN BLUE RIDGE WHERE HEAVY RAINS AND FLOODING OCCURRED. LOCAL
LAW ENFORCEMENT REPORTED THAT SEVERAL WATER RESCUES HAD TAKEN
PLACE IN WESTERN WILKES COUNTY NEAR PARSONVILLE SATURDAY NIGHT.
WITH VERY LOW FLASH FLOOD GUIDANCE OVER WET GROUND...ADDITIONAL
SHOWERS AND THUNDERSTORM REDEVELOPMENT AHEAD AND ALONG THE FRONT
WILL RESULT IN ADDITIONAL FLASH FLOODING. DEPENDING ON EVOLUTION
OF CONVECTION THIS MORNING...MAY NEED TO EXTEND THE FLOOD WATCH IN
TIME AND AREAL COVERAGE. MORE UPDATES LATER THIS MORNING....
AS OF 745 PM EDT SATURDAY...
MORE UNSTABLE SOUPY AIR IS BEING FORCED OUT OF THE GULF OF MEXICO
AHEAD OF A COLD FRONT THROUGH THE OHIO VALLEY. WITH FLOW PARALLEL TO
THE MOUNTAINS...SHOWERS AND SOME EMBEDDED THUNDERSTORMS ARE STUCK
ALONG THE BLUE RIDGE IN NW NC ATTM. WATER PROBLEMS WILL LIKELY
RESULT AGAIN THIS EVENING. THESE STORMS MAY SPREAD INTO THE NC
PIEDMONT LATER THIS EVENING AND AFTER MIDNIGHT AS THE FRONT SLOWLY
MOVES THROUGH THE OHIO VALLEY AND THE MOST UNSTABLE/MOIST AIRMASS
IS SHOVED SLIGHTLY TO THE EAST.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH TUESDAY NIGHT/...
AS OF 400 PM EDT SATURDAY...
ON SUNDAY...THE COLD FRONT WILL ENTER AND THEN MOVE ACROSS THE
REGION. THE BEST ENERGY AND ORGANIZED PRECIPITATION LOOKS AT THIS
POINT TO REMAIN NORTH OF THE REGION. WE WILL CONTINUE TO MONITOR
THESE TRENDS TO SEE IF ANY ADDITIONAL WATCHES WILL BE NEEDED FOR
TOMORROW. FOR NOW...NONE WILL BE ISSUED. COVERAGE WILL BE GREATEST
IN THE EAST DURING THE AFTERNOON WHEN WHERE THE POSITION OF THE
FRONT WILL COINCIDE WITH THE PEAK HEATING OF THE DAY.
CLOSED LOW OVER THE GREAT LAKES WILL GRADUALLY MOVE INTO
SOUTHEASTERN CANADA AND WEAKEN. TROUGH AMPLITUDE WILL DECREASE
THROUGH THE SHORT TERM. IN ITS WAKE...FASTER MORE ZONAL FLOW REGIME
MAY DELIVER A TIGHT DISTURBANCE WHICH WILL SPREAD RAIN AT LEAST
ACROSS THE EXTREME WEST AND SW TUESDAY NIGHT. DOWNSLOPING FLOW WITH
A COOLER AND DRIER AIRMASS SHOULD GIVE US AN OPPORTUNITY TO DRY OUT
BEFORE THAT OCCURS. COULD SEE SHOWERS/POPS HOLDING ACROSS THE
SOUTHSIDE AND PIEDMONT A LITTLE LONGER THAN MODELS SUGGEST SUNDAY
NIGHT. SURFACE HIGH OF DECENT STRENGTH WITH DEWPOINTS IN THE LOWER
50S MONDAY AFTERNOON SHOULD SEND THE COLDEST MOUNTAIN VALLEYS INTO
THE UPPER 40S ONCE AGAIN TUESDAY MORNING. APPEARS AS THOUGH ANY HIGH
CLOUDS WILL HOLD OFF FROM THE SOUTHWEST FOR DECOUPLING TO OCCUR.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 400 PM EDT FRIDAY...
ALTHOUGH THE OP GFS HAS BACKED OFF...THE GEFS AND ECMWF RATHER
BULLISH WITH REGARDS TO WIDESPREAD STRATIFORM RAIN AND POSSIBLY EVEN
AN INSITU WEDGE FOR WEDNESDAY. WITH SURFACE WINDS STILL SHOWING SOME
SOUTHERLY COMPONENT...HESITANT TO GO AS COLD AS AN IN SITU WEDGE
WOULD SUGGEST. HOWEVER...FELT IT WAS PRUDENT TO GO COLDER THAN
GUIDANCE/HPC AT THIS TIME AND PLACE TEMPS RIGHT IN THE MIDDLE OF THE
2M TEMPS AND ECMWF MOS. AN IN SITU WEDGE AND ALL DAY RAIN COULD
EASILY KEEP TEMPS IN THE LOW 70S FOR THE ENTIRE DAY. ONCE THAT
SYSTEM DEPARTS...DEVELOPING REX BLOCK IN THE PAC NW WILL FORCE A
SLICE OF THE FOUR CORNERS UPPER RIDGE AND +20C H85 AIR TO DART INTO
OUR REGION LATE NEXT WEEK. THUS...EXPECTING ISOLATED STORMS IN THE
MOUNTAINS TO END THE FORECAST.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 150 AM EDT SUNDAY...
ALTHOUGH THICK CLOUD COVER IS IN PLACE...PLENTIFUL RAIN AND ENOUGH
LOW LEVEL MOISTURE FOR IFR CEILINGS AND VISIBILITIES AT
BCB/LWB/ROA EARLY THIS MORNING. RADAR CONTINUED TO SHOW ISOLATED
SHOWERS NEAR BLF AND BCB.
A MORE ORGANIZED LINE OF SHOWERS AND THUNDERSTORMS WITH HEAVY RAIN
WILL APPROACH THE AREA EARLY THIS MORNING. LATEST HRRR GUIDANCE
SUGGESTS THIS BAND OF PRECIPITATION WILL REACH BLF AND LWB AROUND
09Z/5AM...BUT CONFIDENCE IN THIS TIMING IS LOW.
A COLD FRONT CROSSES THE AREA THIS AFTERNOON INTO THE EVENING...
AND WILL CONTINUE THE SHOWERS AND STORMS DURING THE DAY.
HIGH PRESSURE WILL BUILD INTO THE REGION BY MONDAY...AND INFLUENCE
OUR WEATHER PATTERN THROUGH TUESDAY. MAINLY VFR CONDITIONS ARE
EXPECTED THROUGH THIS TIME PERIOD WITH LATE NIGHT AND EARLY
MORNING MOUNTAIN AND VALLEY FOG POSSIBLE.
ON WEDNESDAY... AN AREA OF LOW PRESSURE WILL APPROACH AND MOVE
INTO THE AREA. EXPECT A RETURN OF ORGANIZED PRECIPITATION AND
AREAS OF SUB-VFR CONDITIONS AS EARLY AS LATE TUESDAY NIGHT ACROSS
THE WEST.
BY THURSDAY...AN UPPER RIDGE STRETCHES EAST WITH MOUNTAIN
THUNDERSTORMS EXPECTED DURING THE AFTERNOON.
&&
.HYDROLOGY...
FLASH FLOOD WATCH HAS BEEN EXTENDED TO MIDNIGHT TO ALLOW FOR THE
POTENTIAL FOR ISOLATED SHOWERS AND STORMS ARRIVING FROM THE WEST
MOVING OVER AREAS THAT RECEIVED THE HEAVY RAIN TODAY. HAVE ALSO
ADDED GILES AND BLAND COUNTIES IN VIRGINIA. RADAR INDICATES THAT
MOST OF THE WATCH AREA RECEIVED BETWEEN TWO AND FOUR INCHES OF RAIN.
AN QUICK INCH OR TWO OF RAIN FROM ONE OF THE HEAVIER CELLS COULD
PROMPT ADDITIONAL FLASH FLOODING...ESPECIALLY IN AREAS THAT
EXPERIENCED FLASH FLOODING TODAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLASH FLOOD WATCH UNTIL 6 AM EDT EARLY THIS MORNING FOR VAZ015-
016.
NC...FLASH FLOOD WATCH UNTIL 6 AM EDT EARLY THIS MORNING FOR
NCZ001>003-018>020.
WV...NONE.
&&
$$
SYNOPSIS...DS
NEAR TERM...KK/KM
SHORT TERM...DS/KM
LONG TERM...KM
AVIATION...AMS/KM
HYDROLOGY...DS
AREA FORECAST DISCUSSION
NWS SPOKANE WA
445 AM PDT Sun Jul 28 2013
.SYNOPSIS...
A cooling trend back to normal is in progress over the Inland
Northwest. Mainly dry weather is expected through Tuesday with a
few thunderstorms confined to the mountains. Wednesday through
Saturday will be a more active thunderstorm pattern with showers
and thunderstorms becoming common...and progressively wetter over
the region by the end of the week.
&&
.DISCUSSION...
Today through Tuesday...Most of the Inland Northwest is expected
to be dry through Tuesday with seasonal temperatures. There is one
exception however and that is over the mountains near the Canadian
border. For today there is a weak wave that drops south near the
Canadian border with increasing mid level moisture over the
northern mountains...along with an increase in both surface and
mid level instability. The GFS, NAM, ECMWF, and HRRR show
convection developing after 18z (11 am) initially over the Pasayten
Wilderness area, with isolated thunderstorms expanding south into
the mountains around Lake Chelan, and possibly the Okanogan
Highlands and North Idaho Panhandle mountains after 2 pm. There
has been concern with the dry fuels for new fire starts which
remains valid. Good news is that storms will be slow moving and
soundings show that some rain should accompany these storms.
Monday looks like a near repeat with afternoon/evening convection
over the northern mountains. On Tuesday the flow begins to back to
the southwest ahead of a closed low along 130W. Instability once
again lingers over the northern mountains while mid level moisture
begins to increase towards the Blue Mountains and Camas Prairie
where a slight chance of thunderstorms is expected.
With no strong waves expected through Tuesday...lightning is
expected to be generally isolated in nature over the northern
mountains and thus no fire weather highlights are expected at this
time.
Areas of smoke or haze is expected this morning in the Columbia
Basin, Spokane area, and Palouse from wildfires burning around
Goldendale, and south of Wenatchee. JW
Tues Nt through Fri Nt: With the pattern of a stationary upper
trough just off the Pac Nw coast, the region will be at the mercy
of vort maxes ejecting NE into Wa and Oregon. One such wave will
eject Tues Nt, another Wed, followed by a smaller- scale feature
Thurs. All of these occluding waves will consolidate, at least
according to the GFS and ECMWF, into a broad west-to-east
deformation axis along the Nrn periphery of the slowly weakening
upper low. What really stands out in the model guidance is the
lack of meaningful pcpn generated with the first couple ejecting
short- waves. Like the current air-mass, fcst soundings still show
a deep dry layer below about 700mb that will initially inhibit the
potential for heavier pcpn. The time frame between this "dry"
thunder threat and the significantly wetter thunder potential Thurs
Nt and Fri will pose the greatest risk of generating new fire
starts from lightning. Convective wind gusts with these dry
thunderstorms may then help to spread new starts or harass
existing ones. The big question and fcst challenge is determining
where the west- to-east deformation axis mentioned above develops.
There is decent agreement that a nearly stationary band of heavier
widespread pcpn will develop then stall over central or Nrn Wa.
This could be very beneficial for the existing wildfires, but may
produce an increased possibility of heavy runoff for any burn
scars along the East Slopes of the Cascades. bz
Saturday through Sunday night...The upper trough will have pushed
off to the east by this time, but another is poised to make its
way across the Inland Northwest by late in the weekend or early
next week. Any potential shortwave that rotates around the trough
would likely trigger additional precipitation development,
especially with a moist air-mass in place and ample instability
available. The temperatures will begin a slow recovery toward
normal, but most areas will likely be a degree or two just below.
ty
&&
.AVIATION...
12Z TAFS...VFR conditions is expected to continue at all TAF sites
through 12z Monday with terrain driven winds. Wildfire smoke will
continue across the area and could briefly lower visibilities around
KMWH/KPUW but smoke should stay mostly aloft and not impact surface
conditions. North of the TAF sites...close to the Canadian border
afternoon cumulus buildups are expected with a few showers and
thunderstorms this afternoon and evening as the atmosphere
destabilizes. JW
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 85 55 86 59 87 60 / 0 0 0 0 0 20
Coeur d`Alene 83 53 84 55 85 57 / 0 0 10 10 10 30
Pullman 82 44 84 49 86 51 / 0 0 0 0 0 20
Lewiston 91 58 92 61 93 63 / 0 0 0 10 10 30
Colville 88 52 87 52 88 54 / 10 10 10 10 10 20
Sandpoint 81 48 80 50 82 51 / 0 10 10 10 10 20
Kellogg 81 53 82 53 83 55 / 0 0 0 0 0 20
Moses Lake 89 57 90 61 91 62 / 0 0 0 0 0 20
Wenatchee 87 62 88 65 89 66 / 0 0 0 10 10 30
Omak 88 59 88 60 90 60 / 10 10 10 10 10 30
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
241 AM PDT Sun Jul 28 2013
.SYNOPSIS...
A cooling trend back to normal is in progress over the Inland
Northwest. Mainly dry weather is expected through Monday with a
few thunderstorms confined to the mountains. Tuesday through
Saturday will be a more active thunderstorm pattern with showers
and thunderstorms becoming common...and progressively wetter over
the region by the end of the week.
&&
.DISCUSSION...
Today through Tuesday...Most of the Inland Northwest is expected
to be dry through Tuesday with seasonal temperatures. There is one
exception however and that is over the mountains near the Canadian
border. For today there is a weak wave that drops south near the
Canadian border with increasing mid level moisture over the
northern mountains...along with an increase in both surface and
mid level instability. The GFS, NAM, ECMWF, and HRRR show
convection developing after 18z (11 am) initially over the Pasayten
Wilderness area, with isolated thunderstorms expanding south into
the mountains around Lake Chelan, and possibly the Okanogan
Highlands and North Idaho Panhandle mountains after 2 pm. There
has been concern with the dry fuels for new fire starts which
remains valid. Good news is that storms will be slow moving and
soundings show that some rain should accompany these storms.
Monday looks like a near repeat with afternoon/evening convection
over the northern mountains. On Tuesday the flow begins to back to
the southwest ahead of a closed low along 130W. Instability once
again lingers over the northern mountains while mid level moisture
begins to increase towards the Blue Mountains and Camas Prairie
where a slight chance of thunderstorms is expected.
With no strong waves expected through Tuesday...lightning is
expected to be generally isolated in nature over the northern
mountains and thus no fire weather highlights are expected at this
time.
Areas of smoke or haze is expected this morning in the Columbia
Basin, Spokane area, and Palouse from wildfires burning around
Goldendale, and south of Wenatchee. JW
Tues Nt through Fri Nt: With the pattern of a stationary upper
trough just off the Pac Nw coast, the region will be at the mercy
of vort maxes ejecting NE into Wa and Oregon. One such wave will
eject Tues Nt, another Wed, followed by a smaller- scale feature
Thurs. All of these occluding waves will consolidate, at least
according to the GFS and ECMWF, into a broad west-to-east
deformation axis along the Nrn periphery of the slowly weakening
upper low. What really stands out in the model guidance is the
lack of meaningful pcpn generated with the first couple ejecting
short- waves. Like the current air-mass, fcst soundings still show
a deep dry layer below about 700mb that will initially inhibit the
potential for heavier pcpn. The time frame between this "dry"
thunder threat and the significantly wetter thunder potential Thurs
Nt and Fri will pose the greatest risk of generating new fire
starts from lightning. Convective wind gusts with these dry
thunderstorms may then help to spread new starts or harass
existing ones. The big question and fcst challenge is determining
where the west- to-east deformation axis mentioned above develops.
There is decent agreement that a nearly stationary band of heavier
widespread pcpn will develop then stall over central or Nrn Wa.
This could be very beneficial for the existing wildfires, but may
produce an increased possibility of heavy runoff for any burn
scars along the East Slopes of the Cascades. bz
Saturday through Sunday night...The upper trough will have pushed
off to the east by this time, but another is poised to make its
way across the Inland Northwest by late in the weekend or early
next week. Any potential shortwave that rotates around the trough
would likely trigger additional precipitation development,
especially with a moist air-mass in place and ample instability
available. The temperatures will begin a slow recovery toward
normal, but most areas will likely be a degree or two just below.
ty
&&
.AVIATION...
06Z TAFS...Still the only obscuration of concern through 06Z Monday
will be some haze from wildfires in the region. MVFR vis will be
possible at times at KPUW due to the smoke, but vis should improve
through the morning as inversions break. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 85 55 86 59 87 60 / 0 0 0 0 0 20
Coeur d`Alene 83 53 84 55 85 57 / 0 0 10 10 10 30
Pullman 82 44 84 49 86 51 / 0 0 0 0 0 20
Lewiston 91 58 92 61 93 63 / 0 0 0 10 10 30
Colville 88 52 87 52 88 54 / 10 10 10 10 10 20
Sandpoint 81 48 80 50 82 51 / 0 10 10 10 10 20
Kellogg 81 53 82 53 83 55 / 0 0 0 0 0 20
Moses Lake 89 57 90 61 91 62 / 0 0 0 0 0 20
Wenatchee 87 62 88 65 89 66 / 0 0 0 10 10 30
Omak 88 59 88 60 90 60 / 10 10 10 10 10 30
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
604 PM CDT MON JUL 29 2013
.SHORT TERM...(TONIGHT AND TUESDAY)
ISSUED AT 235 PM CDT MON JUL 29 2013
A BIT OF UPPER LEVEL ENERGY WILL WORK WITH THE 850 MB LOW LEVEL
JET/MOISTURE TRANSPORT TO FIRE A SHOWER/THUNDERSTORM COMPLEX IN THE
IA/MO VICINITY TONIGHT...TRACKING IT EAST ON TUES. WHILE THIS
COMPLEX IS EXPECTED TO STAY SOUTH OF THE FORECAST AREA...THERE IS
SOME MEAGER MOISTURE TRANSPORT INTO THE REGION...ALONG WITH A 700 MB
LOW AND WEAK LOW LEVEL TEMPERATURE ADVECTION. MESO MODELS AND 29.12
RUNS OF GFS AND NAM SUGGEST THAT THERE WILL BE ENOUGH CONVERGENCE TO
PRODUCE SCATTERED/ISOLATED SHOWERS LATE TONIGHT THROUGH AT LEAST THE
TUE MORNING. RADAR TRENDS TO THE WEST MIRROR THIS. WILL CONTINUE
SHOWER CHANCES FOR NOW...LITTLE/IF ANY INSTABILITY FOR STORMS.
CHANCES MAY NEED TO BE INCREASED IF THE AREAL COVERAGE LOOKS MORE
WIDESPREAD. AMOUNTS SHOULD BE FAIRLY SMALL FOR THOSE LOCATIONS THAT
RECEIVE SOME RAIN.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 235 PM CDT MON JUL 29 2013
500 MB SHORTWAVE TROUGH STILL ON TRACK TO SLIDE WEST-EAST ACROSS
SOUTHERN CANADA OVER THE NEXT COUPLE DAYS...SKIMMING NORTHERN
PORTIONS OF THE GREAT LAKES ON WED. WHILE THE BULK OF THE UPPER
LEVEL FORCING WILL BE TO THE NORTH...THE SYSTEM WILL DRAG A SFC
FRONT ACROSS THE UPPER MISSISSIPPI RIVER VALLEY. MORE CONSENSUS IN
TIMING OF THE FRONT...WITH THE PREVIOUSLY FAST GFS COMING MORE
INLINE WITH THE NAM AND ECMWF. CONVERGENCE IS SOMEWHAT MEAGER AROUND
THE FRONT...BUT THERE WILL BE ABOUT 1000-1500 J/KG SBCAPE FOR IT TO
TAP...ALTHOUGH BUFKIT SOUNDINGS SHOW ITS FAIRLY SKINNY AND NOT
CONDUCIVE TO STRONG UPDRAFTS. THERE IS GOOD SHEAR OF 35-40 KTS IN
THE 0-6 KM LAYER. IF THE SYSTEM LOOKED MORE DYNAMIC...TIMING WOULD
FAVOR SEVERE WEATHER. AS IT STANDS NOW...SEE STRONG/ISOLATED SEVERE
STORMS MORE LIKELY - AS LONG AS THE INSTABILITY IS THERE. THERE IS
LOW LEVEL WARM AIR ADVECTION/ISENTROPIC UPGLIDE PRE-FRONT...WHICH
COULD RESULT IN SOME CLOUDS/SCATTERED SHOWERS IN THE MORNING. THIS
COULD MUCK UP THE ATMOSPHERE...LEAVING LESS INSTABILITY TO WORK ON.
NOT CLEAR HOW THIS WILL PLAY OUT...BUT THERE WILL BE A GOOD SHOT FOR
SHOWERS/STORMS ON WED...LIKELY MORE WIDESPREAD ACROSS THE NORTH.
ON THU...AREA IS UNDER CYCLONIC FLOW AND THE GFS AND NAM SUGGEST
THAT A PIECE OR TWO OF UPPER LEVEL ENERGY COULD TRACK ACROSS
NORTHERN PARTS OF THE REGION. ADD IN MLCAPES 500-1000 J/KG AND THIS
COULD BE ENOUGH TO SPARK A FEW SHOWERS ACROSS THE NORTH/NORTHEAST.
CONFIDENCE NOT HIGH ENOUGH TO ADD TO THE FORECAST AT THE
MOMENT...BUT IF SIGNAL PERSISTS...SMALL CHANCES WILL BE NEEDED. PCPN
AMOUNTS WOULD BE MINIMAL.
FOR FRIDAY...THE GFS CONTINUES TO FAVOR KEEPING RAIN CHANCES
ASSOCIATED WITH A WEAK SHORTWAVE/LEFT-OVER CONVECTIVE COMPLEX SOUTH
OF THE AREA. A TREND IT STARTED YESTERDAY. THE ECMWF IS ALSO FARTHER
SOUTH...WHICH IT HINTED AT IN ITS PREVIOUS RUN. THE GEM WOULD BRING
US PRETTY GOOD RAINS...DUE TO DEVELOPING THE THU NIGHT STORM COMPLEX
A WHOLE STATE NORTH OF THE OTHER MODELS. GOING TO STICK WITH THE
SOUTHERN SOLUTIONS FOR NOW...WHICH HAS BEEN CONSENSUS.
MODELS HOLD THE PROMISE OF A DRY WEEKEND FOR THE REGION...WITH WEAK
SFC HIGH PRESSURE MOVING OVERHEAD AND ANY RIPPLES IN THE NORTHWEST
FLOW SHUTTLING NORTH OR SOUTH OF THE FORECAST AREA. OF COURSE...IN A
RELATIVELY DIRTY FLOW SUCH AS WHAT IS EXPECTED...THIS CAN CHANGE.
TEMPERATURES WILL BE MUCH MORE PLEASANT COMPARED TO LAST
WEEKEND...BUT THE PATTERN WILL STILL KEEP THEM NEAR OR BELOW THE
LATE JULY/EARLY AUGUST NORMALS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 604 PM CDT MON JUL 29 2013
SHORT WAVE TROUGH CURRENTLY OVER NEBRASKA WILL MOVE SLOWLY EAST
ACROSS IOWA TONIGHT REACHING SOUTHERN LAKE MICHIGAN LATE TUESDAY
AFTERNOON. THE WARM AIR ADVECTION AHEAD OF THE WAVE WILL CREATE
SOME GOOD ISENTROPIC UP GLIDE ON THE 300K SURFACE...BUT THE 29.18Z
NAM SUGGESTS THIS WILL STAY SOUTH OF THE AREA WITH ONLY 1 UBAR/S
OF UP GLIDE REACHING THE IOWA/MINNESOTA BORDER. THE LOW LEVEL
MOISTURE TRANSPORT LOOKS LIKE IT WILL BE FOCUSED INTO THE BEST
ISENTROPIC UP GLIDE AND ALSO STAY SOUTH OF THE AREA. THUS...ONLY
SOME WEAK LIFT IS EXPECTED TO REACH THE TAF SITES WHICH SHOULD
RESULT IN SOME SCATTERED LIGHT SHOWERS OR SPRINKLES DEVELOPING AND
HAVE MAINTAINED THE INCLUSION OF VCSH FOR THE OVERNIGHT INTO
TUESDAY MORNING. WITH THE UNCERTAINTY OF WHETHER ANY RAIN WILL HIT
THE TAF SITES IT ALSO RAISES CONCERNS ON HOW MUCH SATURATION OF
THE LOW LEVELS WILL OCCUR AND WHETHER MVFR CONDITIONS WILL
DEVELOP. THE NAM TRIES TO INDICATE THERE WILL BE ENOUGH RAIN TO
SATURATE THE LOW LEVELS WHILE THE 29.21Z RAP IS NOT NEARLY AS
SATURATED. WITH NOT MUCH RAIN EXPECTED...BELIEVE THE RAP HAS THE
BETTER SOLUTION AT THIS TIME AND HAVE REMOVED THE INCLUSION OF ANY
MVFR CONDITIONS. ONCE THE SHOWERS MOVE PAST BY THE MIDDLE OF THE
MORNING...ENOUGH MID LEVEL MOISTURE SHOULD REMAIN TO MAINTAIN A
VFR CEILING THROUGH THE DAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RIECK
LONG TERM....RIECK
AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
250 PM CDT SUN JUL 28 2013
.SHORT TERM...(TONIGHT AND MONDAY)
ISSUED AT 250 PM CDT SUN JUL 28 2013
LATEST WATER VAPOR IMAGERY PLACED AN UPPER LEVEL LOW OVER THE
MICHIGAN...WITH WARM/MOIST AIR WRAPPING AROUND THE LOW RESULTING IN
WIDESPREAD CLOUDINESS FOR MOST OF WI. THE LOW WILL MEANDER SLOWLY
EAST TONIGHT...ALLOWING FOR A WEAK SFC HIGH OVER THE NORTHERN PLAINS
TO BUILD IN. THE UPPER LEVEL RIDGE AXIS STAYS WEST THROUGH 12Z MON.
EXPECT CLEARING WEST-EAST TONIGHT OF THE CLOUDS AS A RESULT. WITH
THE HIGH ALSO BRINGING IN LIGHT SFC WINDS...THE SPECTER OF RIVER
VALLEY FOG POKES OUT ITS HEAD. CLEAR SKIES...LIGHT WINDS AND RECENT
RAIN ALL FAVOR AT LEAST VALLEY FOG. ITS ALSO GETTING TO THE
CLIMATOLOGICAL FAVORED AUG-SEP-OCT PERIOD FOR RIVER VALLEY FOG.
THAT SAID...THE LOW LEVEL WIND FIELD COULD TEMPER THIS FOG POTENTIAL
QUITE A BIT. 12Z BUFKIT SOUNDINGS VIA THE NAM KEEPS THE WIND
STIRRED IN THE NEAR SFC LAYER...WITH AT LEAST 10 KTS AT 300 FT
THROUGH MIDNIGHT. THE RAP IS MORE BULLISH...HOLDING ONTO THESE
BREEZY NEAR SFC CONDITIONS THROUGH 3 AM. PRELIMINARY LOCAL RESEARCH
SUGGESTS THAT THIS DOES NOT FAVOR DENSE FOG FORMATION AT KLSE. WILL
STILL CONTINUE SOME MENTION OF FOG IN THE VALLEYS FOR EARLY MONDAY
MORNING...BUT IF WIND FIELDS STAY AS FORECAST...IT MAY BE MORE
PATCHY THEN WIDESPREAD.
.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 250 PM CDT SUN JUL 28 2013
THE BRIEF RETURN TO ZONAL FLOW QUICKLY TRANSITIONS TO NORTHWESTERLY
AS MODELS CONTINUE TO COME TO MORE OF A CONSENSUS ON TRACKING AN
UPPER LEVEL SHORTWAVE TROUGH ACROSS SOUTHERN CANADA. SOME
DIFFERENCES IN HOW FAR SOUTH IT DIPS...BUT BOTH THE ECMWF AND GFS
WOULD DRAG AN ASSOCIATED SFC FRONT ACROSS THE UPPER MISSISSIPPI
RIVER VALLEY WED AFTERNOON. THE FRONT DOESN/T LOOK STRONGLY
CONVERGENT AT THIS MOMENT...WITH THE BETTER FORCING WITH THE
UPPER LEVEL SHORTWAVE. TIMING AND PLACEMENT OF THE VARIOUS WEATHER
FEATURES FOR NEXT WEEK HAVE BEEN ALL OVER THE MAP WITH THE
MODELS...SO CONFIDENCE ISN/T OVERLY HIGH WITH TIMING ON THIS FEATURE
YET. THERE IS AN INCREASE IN INSTABILTY/WIND SHEAR AHEAD OF THE
FRONT...AND WHILE NOT OVERTLY HIGH...COULD SUPPORT STRONG/ISOLATED
SEVERE STORMS IF TIMING IS RIGHT.
FRIDAY IS A PERIOD OF CONTENTION FOR THE MODELS...WITH THE 28.12Z
ECMWF CONTINUING TO POINT TO SOME PCPN POTENTIAL FOR AT LEAST THE
SOUTHERN 1/2 OF THE FORECAST AREA. THIS IS MOSTLY ASSOCIATED WITH AN
ANTICIPATED OVERNIGHT THUNDERSTORM COMPLEX OVER THE
PLAINS...TRACKING EAST WITH A RIPPLE IN THE UPPER LEVEL FLOW. GEM IS
SIMILAR TO THE EC WITH SOME RAIN CHANCES ACROSS THE SOUTH...ALTHOUGH
KEEPS THE HIGHER QPF AMOUNTS SOUTH OF THE FORECAST AREA. THE LATEST
GFS KEEPS IT ALL SOUTH...WHICH IS A BIG SHIFT SOUTHWARD COMPARED TO
ITS PREVIOUS RUNS. THAT SAID...BOTH THE EC AND GEM ARE TRENDING
SOUTHWARD WITH THEIR RESPECTIVE QPF FIELDS. WILL CONTINUE PCPN
CHANCES FOR FRI...WITH THE HIGHER CHANCES ACROSS THE SOUTH. TRENDS
MAY EVENTUALLY LEAD TO A DRY FORECAST ACROSS THE NORTH.
TEMPERATURES WILL BE REBOUNDING THIS WEEK AS THE ANOMALOUSLY COLD
AIR EXITS EAST WITH THE UPPER LEVEL TROUGH. STILL...THE PATTERN
FAVORS KEEPING TEMPS A FEW DEGREES ABOVE THE LATE JULY/EARLY AUGUST
NORMALS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1248 PM CDT SUN JUL 28 2013
28.12Z MODELS ARE IN GOOD AGREEMENT THAT THE CLOSED LOW PRESSURE
SYSTEM OVER MICHIGAN WILL DRIFT SLOWLY EAST INTO ONTARIO TONIGHT.
AS THIS OCCURS...THE CYCLONIC FLOW ACROSS THE UPPER MISSISSIPPI
RIVER VALLEY WILL WEAKEN...THUS ALLOWING THE BROKEN 2500 TO 3500
FOOT CLOUD DECK TO DISSIPATE. THIS WILL LIKELY OCCUR AT KRST BY
29.03Z AND AT KLSE AROUND 29.05Z.
FOR LATE TONIGHT...THE MAIN FORECAST CONCERN WILL BE WHETHER
VALLEY FOG WILL DEVELOP. WHILE THERE WILL BE MOSTLY CLEAR
SKIES...THERE IS CONCERN THAT THERE WILL BE 5 TO 10 KNOTS OF WIND
IN THE LOWEST 1 KM. THE NAM SOUNDING SUGGESTS THAT THERE COULD BE
SOME VERY SHALLOW FOG. MEANWHILE THE RUC AND GFS WOULD SAY THAT
THERE WOULD BE NO FOG. SINCE THERE WAS ALREADY 4 SM BR AND A
SCATTERED 600 FT DECK ALREADY IN THE TAF FOR LA CROSSE...DECIDED
NOT TO MAKE ANY CHANGES AT THIS TIME.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RIECK
LONG TERM....RIECK
AVIATION.....BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1249 PM CDT SUN JUL 28 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 343 AM CDT SUN JUL 28 2013
IMPRESSIVE AND ANOMALOUS DEEP LOW PRESSURE SYSTEM OVER THE GREAT
LAKES CONTINUES TO IMPACT THE REGION AND IS THE MAIN FORECAST
PROBLEM FOR THE SHORT TERM.
THE 500MB HEIGHT FIELD WAS JUST OVER A -4 ANOMALY OVER SOUTHERN
LAKE MICHIGAN AT 06Z TONIGHT WITH A -3 850 MB TEMPERATURE
ANOMALY. CLEARLY...THIS IS WHY WE SAW RECORD COOL HIGHS BROKEN
SATURDAY. THE RAIN HELPED TOO. A VERY TIGHT AND DEEP SHORTWAVE
TROUGH ROTATED THROUGH THE FORECAST AREA OVERNIGHT AND WAS LOCATED
OVER THE SRN LAKE MICHIGAN BASIN AT 08Z. SOME SUBSIDENCE WAS SHOWN
IN THE GOES WATER VAPOR IMAGERY VIA DRYING OVER THE FORECAST AREA
BEHIND IT. SURFACE ANALYSIS SHOWED A WIND SHIFT AND TROUGH FROM
KGRB-KDBQ...WHILE RADAR INDICATED SHOWERS ALONG THE I-90 CORRIDOR
AND SOUTH.
THE WARM CONVEYOR BELT AND TROWAL FEATURE FOR THIS DEEP CYCLONE
ARE NOW ROTATING WESTWARD ACROSS LAKE SUPERIOR AND OFFER THE NEXT
WAVE OF PRECIPITATION FOR THE U.P. AND WI. THIS IS THE WEATHER
THAT IS DEVELOPING OVER LAKE SUPERIOR AT 08Z AND HAS MOISTURE
TRANSPORT CONVERGENCE ON THE LEADING EDGE THE MOIST TONGUE THAT
CONTAINS 9C 850MB DEWPOINTS. THIS IS AN IMPRESSIVE MOIST SURGE
THAT IS ISENTROPICALLY LIFTING UP THE THETA/THETAE SURFACES
FLOWING SOUTHWARD. THE MODEL CONSENSUS IS TOO ROTATE THIS
RAINFALL SOUTHWARD INTO NERN WI. THE 28.00Z HI RES NMM AND ARW
MODELS...AND HRRR RUNS ARE ALL CONSISTENT IN BRUSHING THE NORTHCENTRAL
WI AREAS AND THUS HAVE MADE A SLIGHT BUMP THERE TO THE RAIN CHANCES.
THE MAJORITY OF THE RAINFALL WILL BE EAST...MAINLY SCATTERED
SHOWERS IN THE CENTRAL. HAVE LEFT MOST OF THE FORECAST AREA
DRY...BUT THIS WILL HAVE TO BE MONITORED CLOSELY WITH THE
TRAJECTORY OF THE FORCING...SOME WEAK INSTABILITY AND SHOWERS
COULD DEVELOP A BIT FURTHER WEST.
OVERALL.. THE AREA WILL START TO RAPIDLY STABILIZE BY MID-AFTERNOON
INTO EVENING...WITH THE SHOWER CHANCES/COVERAGE BEST THIS MORNING
AND THEN INTO THE AFTERNOON WITH A BIT OF HEATING EXPECTED.
ALTHOUGH THE AREA IS UNDER WARM ADVECTION TODAY AND THE LOW-LEVEL
TEMPERATURE ANOMALY INCREASES TO -2 BY THIS EVENING...THERE COULD
STILL BE SOME RECORD COOL HIGHS AGAIN TODAY WITH CLOUDS IN PLACE.
TONIGHT...HAVE SLOWED THE CLOUD TRENDS EASTWARD A BIT OVERNIGHT AS
THERE IS SOME SUGGESTION IN THE 28.00Z GFS/NAM 800-900MB RH THAT
MOISTURE MAY LINGER IN CYCLONIC FLOW. HEIGHTS ARE BUILDING SO
CLEARING WILL LIKELY TAKE PLACE...BUT WAS CONSERVATIVE THERE.
VALLEY FOG...HAVE PERKED UP THE IDEA OF RIVER VALLEY FOG AS THE
WINDS REALLY DROP OFF THROUGH 2 KMS /BELOW 10KTS/ TONIGHT AND INTO
MONDAY MORNING. COOLER HIGHS ON SUNDAY...DEEP LIGHT WINDS...
RECENT RAIN...AND CLEARING SKIES ALL POINT TOWARD FOG. THE BIG
NEGATIVE IS THE SKY CLEARING. IF IT CLEARS EARLY EVENING...RIVER
VALLEY FOG MAY BE WIDESPREAD MONDAY MORNING. HAVE INTRODUCED THIS
INTO THE FORECAST. NAM/GFS MOS DO NOT HAVE FOG AT KLSE...NOT SURE
WHY THERE ISNT A SNIFF OF FOG AT LEAST INDICATED.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 343 AM CDT SUN JUL 28 2013
GENERALLY QUIET WEATHER IS EXPECTED WITH SYSTEMS MOVING TO THE
SOUTH AND NORTH OF THE FORECAST AREA...ONLY GLANCING BLOWS
POSSIBLE. TEMPERATURES WILL CONTINUE TO NORMALIZE AND HIGH
PRESSURE AND RIDGING SHOULD DOMINATE.
THERE SEEMS TO BE GOOD DEVELOPING CONSENSUS OF ANOTHER ROUND OF
LONG WAVE...DEEP TROUGHING OVER HUDSONS BAY...LEAVING THE REGION
IN A NWRLY FLOW REGIME WITH PERIODIC WEATHER SYSTEMS. THE FIRST
TRANSITION SHORTWAVE TROUGH ARRIVES WEDNESDAY WITH GOOD AGREEMENT
GROWING ON RAIN AND THUNDER OCCURRING. IT APPEARS THE WIND SHEAR
AND CAPE WILL BE MODERATE...YIELDING A SEVERE WEATHER CHANCE. THAT
WOULD BEGIN A BETTER WIND SHEAR PERIOD WHERE SEVERE WEATHER
CHANCES WOULD DEPEND MORE ON DEVELOPING CAPE AS THE AREA IS WITHIN
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1248 PM CDT SUN JUL 28 2013
28.12Z MODELS ARE IN GOOD AGREEMENT THAT THE CLOSED LOW PRESSURE
SYSTEM OVER MICHIGAN WILL DRIFT SLOWLY EAST INTO ONTARIO TONIGHT.
AS THIS OCCURS...THE CYCLONIC FLOW ACROSS THE UPPER MISSISSIPPI
RIVER VALLEY WILL WEAKEN...THUS ALLOWING THE BROKEN 2500 TO 3500
FOOT CLOUD DECK TO DISSIPATE. THIS WILL LIKELY OCCUR AT KRST BY
29.03Z AND AT KLSE AROUND 29.05Z.
FOR LATE TONIGHT...THE MAIN FORECAST CONCERN WILL BE WHETHER
VALLEY FOG WILL DEVELOP. WHILE THERE WILL BE MOSTLY CLEAR
SKIES...THERE IS CONCERN THAT THERE WILL BE 5 TO 10 KNOTS OF WIND
IN THE LOWEST 1 KM. THE NAM SOUNDING SUGGESTS THAT THERE COULD BE
SOME VERY SHALLOW FOG. MEANWHILE THE RUC AND GFS WOULD SAY THAT
THERE WOULD BE NO FOG. SINCE THERE WAS ALREADY 4 SM BR AND A
SCATTERED 60 FOOT DECK ALREADY IN THE TAF FOR LA CROSSE...DECIDED
NOT TO MAKE ANY CHANGES AT THIS TIME.
&&
.CLIMATE...TODAY
ISSUED AT 345 AM CDT SUN JUL 28 2013
RECORD LOW MAXIMUM TEMPERATURES FOR TODAY...
AUSTIN MN 63 IN 1991
ROCHESTER MN 63 IN 1991
CHARLES CITY IA 69 IN 1981
DECORAH IA 69 IN 1962
MEDFORD WI 61 IN 1944
LA CROSSE WI 66 IN 1991
PRAIRIE DU CHIEN WI 68 IN 1981
SPARTA WI 70 IN 1971
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BAUMGARDT
LONG TERM...BAUMGARDT
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
602 AM CDT SUN JUL 28 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 343 AM CDT SUN JUL 28 2013
IMPRESSIVE AND ANOMALOUS DEEP LOW PRESSURE SYSTEM OVER THE GREAT
LAKES CONTINUES TO IMPACT THE REGION AND IS THE MAIN FORECAST
PROBLEM FOR THE SHORT TERM.
THE 500MB HEIGHT FIELD WAS JUST OVER A -4 ANOMALY OVER SOUTHERN
LAKE MICHIGAN AT 06Z TONIGHT WITH A -3 850 MB TEMPERATURE
ANOMALY. CLEARLY...THIS IS WHY WE SAW RECORD COOL HIGHS BROKEN
SATURDAY. THE RAIN HELPED TOO. A VERY TIGHT AND DEEP SHORTWAVE
TROUGH ROTATED THROUGH THE FORECAST AREA OVERNIGHT AND WAS LOCATED
OVER THE SRN LAKE MICHIGAN BASIN AT 08Z. SOME SUBSIDENCE WAS SHOWN
IN THE GOES WATER VAPOR IMAGERY VIA DRYING OVER THE FORECAST AREA
BEHIND IT. SURFACE ANALYSIS SHOWED A WIND SHIFT AND TROUGH FROM
KGRB-KDBQ...WHILE RADAR INDICATED SHOWERS ALONG THE I-90 CORRIDOR
AND SOUTH.
THE WARM CONVEYOR BELT AND TROWAL FEATURE FOR THIS DEEP CYCLONE
ARE NOW ROTATING WESTWARD ACROSS LAKE SUPERIOR AND OFFER THE NEXT
WAVE OF PRECIPITATION FOR THE U.P. AND WI. THIS IS THE WEATHER
THAT IS DEVELOPING OVER LAKE SUPERIOR AT 08Z AND HAS MOISTURE
TRANSPORT CONVERGENCE ON THE LEADING EDGE THE MOIST TONGUE THAT
CONTAINS 9C 850MB DEWPOINTS. THIS IS AN IMPRESSIVE MOIST SURGE
THAT IS ISENTROPICALLY LIFTING UP THE THETA/THETAE SURFACES
FLOWING SOUTHWARD. THE MODEL CONSENSUS IS TOO ROTATE THIS
RAINFALL SOUTHWARD INTO NERN WI. THE 28.00Z HI RES NMM AND ARW
MODELS...AND HRRR RUNS ARE ALL CONSISTENT IN BRUSHING THE NORTHCENTRAL
WI AREAS AND THUS HAVE MADE A SLIGHT BUMP THERE TO THE RAIN CHANCES.
THE MAJORITY OF THE RAINFALL WILL BE EAST...MAINLY SCATTERED
SHOWERS IN THE CENTRAL. HAVE LEFT MOST OF THE FORECAST AREA
DRY...BUT THIS WILL HAVE TO BE MONITORED CLOSELY WITH THE
TRAJECTORY OF THE FORCING...SOME WEAK INSTABILITY AND SHOWERS
COULD DEVELOP A BIT FURTHER WEST.
OVERALL.. THE AREA WILL START TO RAPIDLY STABILIZE BY MID-AFTERNOON
INTO EVENING...WITH THE SHOWER CHANCES/COVERAGE BEST THIS MORNING
AND THEN INTO THE AFTERNOON WITH A BIT OF HEATING EXPECTED.
ALTHOUGH THE AREA IS UNDER WARM ADVECTION TODAY AND THE LOW-LEVEL
TEMPERATURE ANOMALY INCREASES TO -2 BY THIS EVENING...THERE COULD
STILL BE SOME RECORD COOL HIGHS AGAIN TODAY WITH CLOUDS IN PLACE.
TONIGHT...HAVE SLOWED THE CLOUD TRENDS EASTWARD A BIT OVERNIGHT AS
THERE IS SOME SUGGESTION IN THE 28.00Z GFS/NAM 800-900MB RH THAT
MOISTURE MAY LINGER IN CYCLONIC FLOW. HEIGHTS ARE BUILDING SO
CLEARING WILL LIKELY TAKE PLACE...BUT WAS CONSERVATIVE THERE.
VALLEY FOG...HAVE PERKED UP THE IDEA OF RIVER VALLEY FOG AS THE
WINDS REALLY DROP OFF THROUGH 2 KMS /BELOW 10KTS/ TONIGHT AND INTO
MONDAY MORNING. COOLER HIGHS ON SUNDAY...DEEP LIGHT WINDS...
RECENT RAIN...AND CLEARING SKIES ALL POINT TOWARD FOG. THE BIG
NEGATIVE IS THE SKY CLEARING. IF IT CLEARS EARLY EVENING...RIVER
VALLEY FOG MAY BE WIDESPREAD MONDAY MORNING. HAVE INTRODUCED THIS
INTO THE FORECAST. NAM/GFS MOS DO NOT HAVE FOG AT KLSE...NOT SURE
WHY THERE ISNT A SNIFF OF FOG AT LEAST INDICATED.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 343 AM CDT SUN JUL 28 2013
GENERALLY QUIET WEATHER IS EXPECTED WITH SYSTEMS MOVING TO THE
SOUTH AND NORTH OF THE FORECAST AREA...ONLY GLANCING BLOWS
POSSIBLE. TEMPERATURES WILL CONTINUE TO NORMALIZE AND HIGH
PRESSURE AND RIDGING SHOULD DOMINATE.
THERE SEEMS TO BE GOOD DEVELOPING CONSENSUS OF ANOTHER ROUND OF
LONG WAVE...DEEP TROUGHING OVER HUDSONS BAY...LEAVING THE REGION
IN A NWRLY FLOW REGIME WITH PERIODIC WEATHER SYSTEMS. THE FIRST
TRANSITION SHORTWAVE TROUGH ARRIVES WEDNESDAY WITH GOOD AGREEMENT
GROWING ON RAIN AND THUNDER OCCURRING. IT APPEARS THE WIND SHEAR
AND CAPE WILL BE MODERATE...YIELDING A SEVERE WEATHER CHANCE. THAT
WOULD BEGIN A BETTER WIND SHEAR PERIOD WHERE SEVERE WEATHER
CHANCES WOULD DEPEND MORE ON DEVELOPING CAPE AS THE AREA IS WITHIN
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 602 AM CDT SUN JUL 28 2013
ANOTHER DAY OF CHILLY CYCLONIC FLOW ACROSS THE REGION. THIS WILL
RESULT IN MVFR CLOUD COVER AT BOTH KRST/KLSE. ANY SHOWER ACTIVITY
IS EXPECTED TO REMAIN NORTHEAST OF THE TAF SITES...MAINLY
NORTHEAST IF I-94. LOOK FOR THE CLOUDS TO RISE INTO THE VFR RANGE
IN THE 17-19Z TIME FRAME...AND THEN EVENTUALLY SCATTER OUT EARLY
THIS EVENING. CLEARING SKIES...LIGHT WINDS AND A MOIST LOWER
BOUNDARY LAYER MAY LEAD TO SOME FOG/STRATUS FORMATION...MAINLY IN
THE RIVER VALLEYS INCLUDING THE KLSE AIRPORT. NOT CONFIDENT ON HOW
THICK/DENSE FOG WILL BECOME AND WILL DEPEND ON HOW FAST THE CLOUDS
SCATTER. FOR NOW...WENT WITH 4SM BR SCT006 AT KLSE IN THE 10-12Z
TIME FRAME. WILL CONTINUE TO MONITOR AND ADJUST AS NECESSARY.
&&
.CLIMATE...TODAY
ISSUED AT 345 AM CDT SUN JUL 28 2013
RECORD LOW MAXIMUM TEMPERATURES FOR TODAY...
AUSTIN MN 63 IN 1991
ROCHESTER MN 63 IN 1991
CHARLES CITY IA 69 IN 1981
DECORAH IA 69 IN 1962
MEDFORD WI 61 IN 1944
LA CROSSE WI 66 IN 1991
PRAIRIE DU CHIEN WI 68 IN 1981
SPARTA WI 70 IN 1971
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BAUMGARDT
LONG TERM...BAUMGARDT
AVIATION...DAS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
344 AM CDT SUN JUL 28 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 343 AM CDT SUN JUL 28 2013
IMPRESSIVE AND ANOMALOUS DEEP LOW PRESSURE SYSTEM OVER THE GREAT
LAKES CONTINUES TO IMPACT THE REGION AND IS THE MAIN FORECAST
PROBLEM FOR THE SHORT TERM.
THE 500MB HEIGHT FIELD WAS JUST OVER A -4 ANOMALY OVER SOUTHERN
LAKE MICHIGAN AT 06Z TONIGHT WITH A -3 850 MB TEMPERATURE
ANOMALY. CLEARLY...THIS IS WHY WE SAW RECORD COOL HIGHS BROKEN
SATURDAY. THE RAIN HELPED TOO. A VERY TIGHT AND DEEP SHORTWAVE
TROUGH ROTATED THROUGH THE FORECAST AREA OVERNIGHT AND WAS LOCATED
OVER THE SRN LAKE MICHIGAN BASIN AT 08Z. SOME SUBSIDENCE WAS SHOWN
IN THE GOES WATER VAPOR IMAGERY VIA DRYING OVER THE FORECAST AREA
BEHIND IT. SURFACE ANALYSIS SHOWED A WIND SHIFT AND TROUGH FROM
KGRB-KDBQ...WHILE RADAR INDICATED SHOWERS ALONG THE I-90 CORRIDOR
AND SOUTH.
THE WARM CONVEYOR BELT AND TROWAL FEATURE FOR THIS DEEP CYCLONE
ARE NOW ROTATING WESTWARD ACROSS LAKE SUPERIOR AND OFFER THE NEXT
WAVE OF PRECIPITATION FOR THE U.P. AND WI. THIS IS THE WEATHER
THAT IS DEVELOPING OVER LAKE SUPERIOR AT 08Z AND HAS MOISTURE
TRANSPORT CONVERGENCE ON THE LEADING EDGE THE MOIST TONGUE THAT
CONTAINS 9C 850MB DEWPOINTS. THIS IS AN IMPRESSIVE MOIST SURGE
THAT IS ISENTROPICALLY LIFTING UP THE THETA/THETAE SURFACES
FLOWING SOUTHWARD. THE MODEL CONSENSUS IS TOO ROTATE THIS
RAINFALL SOUTHWARD INTO NERN WI. THE 28.00Z HI RES NMM AND ARW
MODELS...AND HRRR RUNS ARE ALL CONSISTENT IN BRUSHING THE NORTHCENTRAL
WI AREAS AND THUS HAVE MADE A SLIGHT BUMP THERE TO THE RAIN CHANCES.
THE MAJORITY OF THE RAINFALL WILL BE EAST...MAINLY SCATTERED
SHOWERS IN THE CENTRAL. HAVE LEFT MOST OF THE FORECAST AREA
DRY...BUT THIS WILL HAVE TO BE MONITORED CLOSELY WITH THE
TRAJECTORY OF THE FORCING...SOME WEAK INSTABILITY AND SHOWERS
COULD DEVELOP A BIT FURTHER WEST.
OVERALL.. THE AREA WILL START TO RAPIDLY STABILIZE BY MID-AFTERNOON
INTO EVENING...WITH THE SHOWER CHANCES/COVERAGE BEST THIS MORNING
AND THEN INTO THE AFTERNOON WITH A BIT OF HEATING EXPECTED.
ALTHOUGH THE AREA IS UNDER WARM ADVECTION TODAY AND THE LOW-LEVEL
TEMPERATURE ANOMALY INCREASES TO -2 BY THIS EVENING...THERE COULD
STILL BE SOME RECORD COOL HIGHS AGAIN TODAY WITH CLOUDS IN PLACE.
TONIGHT...HAVE SLOWED THE CLOUD TRENDS EASTWARD A BIT OVERNIGHT AS
THERE IS SOME SUGGESTION IN THE 28.00Z GFS/NAM 800-900MB RH THAT
MOISTURE MAY LINGER IN CYCLONIC FLOW. HEIGHTS ARE BUILDING SO
CLEARING WILL LIKELY TAKE PLACE...BUT WAS CONSERVATIVE THERE.
VALLEY FOG...HAVE PERKED UP THE IDEA OF RIVER VALLEY FOG AS THE
WINDS REALLY DROP OFF THROUGH 2 KMS /BELOW 10KTS/ TONIGHT AND INTO
MONDAY MORNING. COOLER HIGHS ON SUNDAY...DEEP LIGHT WINDS...
RECENT RAIN...AND CLEARING SKIES ALL POINT TOWARD FOG. THE BIG
NEGATIVE IS THE SKY CLEARING. IF IT CLEARS EARLY EVENING...RIVER
VALLEY FOG MAY BE WIDESPREAD MONDAY MORNING. HAVE INTRODUCED THIS
INTO THE FORECAST. NAM/GFS MOS DO NOT HAVE FOG AT KLSE...NOT SURE
WHY THERE ISNT A SNIFF OF FOG AT LEAST INDICATED.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 343 AM CDT SUN JUL 28 2013
GENERALLY QUIET WEATHER IS EXPECTED WITH SYSTEMS MOVING TO THE
SOUTH AND NORTH OF THE FORECAST AREA...ONLY GLANCING BLOWS
POSSIBLE. TEMPERATURES WILL CONTINUE TO NORMALIZE AND HIGH
PRESSURE AND RIDGING SHOULD DOMINATE.
THERE SEEMS TO BE GOOD DEVELOPING CONSENSUS OF ANOTHER ROUND OF
LONG WAVE...DEEP TROUGHING OVER HUDSONS BAY...LEAVING THE REGION
IN A NWRLY FLOW REGIME WITH PERIODIC WEATHER SYSTEMS. THE FIRST
TRANSITION SHORTWAVE TROUGH ARRIVES WEDNESDAY WITH GOOD AGREEMENT
GROWING ON RAIN AND THUNDER OCCURRING. IT APPEARS THE WIND SHEAR
AND CAPE WILL BE MODERATE...YIELDING A SEVERE WEATHER CHANCE. THAT
WOULD BEGIN A BETTER WIND SHEAR PERIOD WHERE SEVERE WEATHER
CHANCES WOULD DEPEND MORE ON DEVELOPING CAPE AS THE AREA IS WITHIN
THE ESTABLISHED NWRLY FLOW. FRIDAY MAY BE THAT NEXT CHANCE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1146 PM CDT SAT JUL 27 2013
THE CLOSED UPPER LEVEL LOW CONTINUES TO DRIFT SLOWLY SOUTHEAST
ACROSS WISCONSIN THIS EVENING. THE SHORT TROUGH ON THE NORTHWEST
SIDE OF THE LOW HAS SLIPPED INTO EASTERN MINNESOTA AND NORTHWEST
WISCONSIN AND CONTINUES TO PRODUCE SOME NON-VISIBILITY REDUCING
LIGHT RAIN OR DRIZZLE. KARX RADAR INDICATES MOST OF THIS IS OR
WILL SHORTLY BE SOUTH OF BOTH TAF SITES SO WILL ONLY INCLUDE A
VCSH. MVFR CEILINGS UNDER THE SHORT WAVE TROUGH CONTINUE TO MAKE
SLOW SOUTHWARD PROGRESS AND STILL EXPECT THESE TO SPREAD OVER BOTH
TAF SITES AS THE NIGHT PROGRESSES. THESE SHOULD LIFT TO VFR SUNDAY
MORNING AS SOME WEAK HEATING AND MIXING GETS GOING. AS THE WHOLE
SYSTEM MOVES OFF TO THE EAST SUNDAY AFTERNOON AND EVENING...THE
MOISTURE WILL BEGIN TO DIMINISH SETTING THE STAGE FOR CLEARING.
THE 28.00Z NAM IS NOW SLOWER WITH THE CLEARING THAN THE 27.18Z RUN
AND KEEPS THE CYCLONIC FLOW IN PLACE THROUGH THE EVENING. COULD
SEE KRST SCATTERING OUT SUNDAY EVENING BUT FOR NOW WILL KEEP THE
CLOUDS IN PLACE.
&&
.CLIMATE...TODAY
ISSUED AT 345 AM CDT SUN JUL 28 2013
RECORD LOW MAXIMUM TEMPERATURES FOR TODAY...
AUSTIN MN 63 IN 1991
ROCHESTER MN 63 IN 1991
CHARLES CITY IA 69 IN 1981
DECORAH IA 69 IN 1962
MEDFORD WI 61 IN 1944
LA CROSSE WI 66 IN 1991
PRAIRIE DU CHIEN WI 68 IN 1981
SPARTA WI 70 IN 1971
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BAUMGARDT
LONG TERM...BAUMGARDT
AVIATION...04
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1043 PM MDT MON JUL 29 2013
.UPDATE...
ISSUED AT 925 PM MDT MON JUL 29 2013
ACTIVE EVENING WITH JET CORE OVERHEAD AND SPEED MAX OF 80 KT SEEN
IN 00Z KGJT SOUNDING. IN ADDITION SHORTWAVE UPSTREAM OVER NORTHERN
UTAH CONTINUES TO MOVE EAST SUPPORTING THE LATEST ROUND OF
THUNDERSTORMS...ONE ENTERING NW CO AND THE OTHER FOLLOWING ON THE
HEELS OF EARLIER STRONG CONVECTION THAT TRACKED FROM CANYONLANDS
ALMOST DUE EAST OVER THE UNCOMPAHGRE PLATEAU...MONTROSE AND
GUNNISON. HRRR MODEL ADVERTISED AND IS HANDLING THESE TWO
SEPARATE AREAS VERY WELL ALTHOUGH PERHAPS A COUPLE OF HOURS SLOW.
EXPECT THIS ROUND TO BE THE LAST ONE FOR THE NIGHT...CLEARING THE
DIVIDE BY 4 AM. AREA UNDER MODERATE DEEP LAYER SHEAR AND
RELATIVELY HIGHER MUCAPES WHICH IS HELPING TO KEEP STORMS A LITTLE
BETTER ORGANIZED AND LONGER-LIVED. HOWEVER...DUE TO THE GENERAL
DOWNWARD TREND IN INTENSITY WITH STABILIZATION OVERNIGHT...FLASH
FLOOD WATCH HAS BEEN ALLOWED TO EXPIRE. REMAINING STORMS WILL BE
WEAKER...ALTHOUGH STILL CAPABLE OF PRODUCING BRIEF AND LOCALLY
HEAVY RAIN.
&&
.SHORT TERM...(TONIGHT THROUGH TUESDAY NIGHT)
220 PM MDT MON JUL 29 2013
SHORT WAVE ENERGY OVER UTAH WILL STREAM EASTWARD AND WILL BE THE
PRIMARY TRIGGER FOR LOCALIZED HEAVY SHOWERS. THE PRIME AREA
APPEARS TO BE THE MIDDLE SECTION OF THE FORECAST AREA...WITH THE
ENVIRONMENT ACROSS THE FAR SOUTH AND NEAR THE WYOMING BORDER NOT
AS CONDUCIVE FOR RECEIVING HEAVY SHOWERS. SPEED MAXIMA ALOFT IS
ASSOCIATED WITH THE SHORT WAVE AND MAY ENHANCE STORM TOP
DIVERGENCE AND HELP GENERATE LOCALIZED STRONG CELLS WITH SMALL
HAIL. THE PRIMARY THREAT REMAINS HEAVY RAINERS FROM TRAINING
CELLS. WITH SOME AREAS HAVING RECEIVED SIGNIFICANT RAINFALL THE
PAST TWO DAYS...THE FLASH FLOOD THREAT IS ELEVATED FOR THE
REMAINDER OF THE DAY. GIVEN THAT THE MOISTURE STREAM TRAILS BACK
TO NE NEVADA...SHOWERS WITH EMBEDDED STORMS MAY LINGER ACROSS THE
NORTH UNTIL LATE.
TUESDAY AND TUESDAY NIGHT...HIGH PRESSURE RIDGE BUILDS BEHIND DEPARTING
SHORT WAVE FOR INCREASED SUBSIDENCE AND DRY ADVECTION ALOFT. THIS
WEAKENS THE MONSOONAL MOISTURE STREAM INTO THE FOUR CORNERS AREA.
ACROSS THE NORTH... MOISTURE STREAM IS WEAKENING BUT STILL EXIST
FOR SCATTERED SHOWERS AND STORMS OVER NW COLORADO. ACROSS THE SRN
HALF WHERE LESS MID LEVEL FLOW EXISTS...DIABATIC HEATING OVER THE
HIGH TERRAIN WILL BE THE PRIMARY CONVECTIVE TRIGGER. AFTERNOON
CONVECTION SHOULD DIMINISH QUICKLY NEAR SUNSET AND BECOME MOSTLY
CLEAR OVERNIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
220 PM MDT MON JUL 29 2013
DRY CONDITIONS WITH VERY LIGHT WESTERLY FLOW CONTINUE THROUGH
WEDNESDAY NIGHT UNDER HIGH PRESSURE BEFORE A SHIFT TO
SOUTH/SOUTHWESTERLY FLOW. BY THURSDAY AFTERNOON PWAT VALUES
INCREASE TO A CONVECTION- FAVORABLE 0.8 TO 1.0 INCH OVER MUCH OF
THE AREA...ESPECIALLY OVER SOUTHEAST UTAH. TWO UPPER LEVEL
DISTURBANCES LOOK TO MOVE THROUGH EARLY THURSDAY MORNING AND
THURSDAY AFTERNOON...WHICH SUPPORT SCATTERED CONVECTION AROUND THE
AREA ESPECIALLY ALONG THE COLORADO RIVER CORRIDOR. AREAS IN
NORTHERN COLORADO/UTAH MAY SEE SHOWER INITIATION BY THE UPPER LEVEL JET AS
WELL. THE FIRST BURST OF ENERGY WILL BE WEAK...BUT MAY ALLOW SOME
THURSDAY MORNING CONVECTION UP OVER ELEVATED AREAS OF CENTRAL
COLORADO. CONVECTIVE ACTIVITY WILL INCREASE WITH SOLAR HEATING AND
WHILE A FEW LIGHT SHOWERS MAY PERSIST THROUGH THE NIGHT...MOST
WILL DISSIPATE AFTER SUNSET THURSDAY EVENING ONCE THE SHEAR AXIS
MOVES THROUGH THE AREA.
12Z GFS SHOWS A THIRD WEAK SHORTWAVE THURSDAY NIGHT ALONG THE
SOUTHERN UT/CO BORDER...BUT THE ECMWF HAS NOT RESOLVED THIS
FEATURE YET. A COUPLE OF SMALL DISTURBANCES ARE SCATTERED AMONG THE WX
MODELS THROUGH SATURDAY BUT WITH THESE DIFFERING OPINIONS...NOT
INCLINED TO FORECAST ENHANCED POPS FOR ANY OF THE FEATURES PAST
THURSDAY NIGHT.
SATURDAY NIGHT THROUGH MONDAY...LOW CONFIDENCE WITH LONG RANGE FORECAST
AT THIS TIME. GFS HAS HIGH PRESSURE PROGGED TO SHIFT SOUTHEAST AS
LOW PRESSURE MOVES EAST ALONG THE CANADA/US BORDER OVER NORTHERN
MONTANA. THIS WOULD CUT OFF THE MONSOONAL MOISTURE PLUME AGAIN
LIKELY UNTIL MID NEXT WEEK SOMETIME. 12Z ECMWF DIFFERS IN SHIFTING
THE TRANSPORT WINDS TO WESTERLY ON SUNDAY EVENING AND CONTINUING
DAILY DIURNAL SHOWERS INTO NEXT WEEK ALONG THE RIDGE AXIS.
TEMPERATURES WILL REMAIN NEAR NORMAL THROUGH MIDWEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1043 PM MDT MON JUL 29 2013
KMTJ...KASE AND KEGE WILL HAVE SHRA IN THE VICINITY THROUGH
09Z...POSSIBLY A LITTLE THUNDER AT KMTJ. VFR CONDITIONS WILL
PREVAIL WITH DIURNAL CYCLE OF WINDS TAKING OVER. CONVECTION AFT
18Z TUE SHOULD BE LIMITED TO THE MOUNTAINS...WITH DRIER AIR
SPREADING IN FROM THE WEST. CONFIDENCE A LITTLE HIGHER THAN ON 00Z
ISSUANCE...SO HAVE PUT VCTS AT KASE AND KEGE.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
UPDATE...BWM
SHORT TERM...PF
LONG TERM...JAM
AVIATION...BWM
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
248 AM EDT Tue Jul 30 2013
.NEAR TERM [Through Today]...
The upper trough continues to lift northeast across the Northeast
and eastern Canada leaving a broad ridge stretching across the Gulf
Coast. Overall steering flow will remain light today resulting in a
type 1 sea breeze regime. We used some sea breeze climo in today`s
forecast but tempered to account for lower than normal precipitable
water north of the FL border. We also blended in some of the CAM and
MOS data. The result is chance PoPs (30-40%) across the southern
half of the CWA and slight chance (20%) across the northern half.
These latter areas will be a bit hotter with highs in the mid 90s.
VLD could once again reach upper 90s. In FL, look for highs mainly
in the lower 90s inland and upper 80s near the coast.
&&
.SHORT TERM [Tonight Through Thursday]...
Beginning tonight, another shortwave will slide out of the
Mississippi Valley, into the Southeast. The effects of this will
be to nudge the mid/upper layer ridge back to the west and begin
the transition back to the all too familiar pattern highlighted
by a trough over much of the eastern part of the country, and a
persistent ridge centered over the Southwest/Southern Plains.
At the surface, high pressure over the northern Gulf will weaken
and the surface pattern across the Southeast will likely be
dominated by some sort of broad, weak, low pressure in the form of
a trough.
The surface trough will likely be the main focus for thunderstorm
development, and the distribution of rain will be highly dependent
on the exact positioning of the trough. On Wednesday, there will
most likely be some sort of mixed contribution from the Gulf Coast
Seabreeze and the trough, while Thursday will likely be too
disturbed to discern an organized seabreeze circulation.
Localized flooding may be a concern as precipitable water values
rise to slightly above seasonal averages. This will primarily be a
concern on Wednesday when cloud bearing steering flow will be
rather weak, and storms may easily link to mesoscale/synoptic
boundaries. By Thursday, a more steady westerly steering flow
should become established, lessening the flooding threat. However,
in general do not expect any sort of widespread flooding concerns
as average storm totals Wed-Thurs should be around the 0.5 to 1.5
inch range.
The severe weather potential remains low at this time. The best
chance for any strong to severe storm development appears to be on
Thursday, closer to southeast Alabama should the arrival of
steeper mid-level lapse rates time up just right with afternoon
storms. The primary threat would be damaging wind gusts.
&&
.LONG TERM [Thursday Night through Monday]...
The pattern will remain fairly into Friday, as the parent upper
level trough builds south over the Southeast and moist air
remains in place over our region. While this feature is expected
to move into the Atlantic by the weekend and will be replaced by
an upper ridge, PWAT values are forecast to remain near 2" over
our region through the rest of the period, and a stationary front
is projected to remain just north of our region throughout this
period. As a result, scattered showers and thunderstorms will
remain possible each day, especially during the afternoon and
early evenings. Temperatures should remain fairly seasonable, with
highs in the low 90s and lows in the 70s.
&&
.AVIATION [Beginning 06Z Tuesday]...
Hi res guidance including the HRRR indicate that there is a much
lower chance for low cigs this morning. We are mainly calling for
a period of MVFR visibility. ECP may briefly see an MVFR ceiling
in the hours surrounding sunrise. Overall convective coverage will
be low enough to preclude mention in the DHN and ABY TAFs.
Convection will be mentioned in the vicinity only at ECP, TLH and
VLD.
&&
.MARINE...
High pressure transitioning to a broad, weak, low pressure pattern
will keep wind and seas calm through the weekend. Scattered
showers and thunderstorms will be most common Wed-Fri, with typical
summertime nocturnal storms otherwise.
&&
.FIRE WEATHER...
Red Flag conditions are not anticipated this week. Dispersion
indices will remain very low today.
&&
.HYDROLOGY...
Water levels on all area river systems are on the downward trend,
and for the most part will remain this way for the next several
days. With above average rain chances mid to late week, these
decreases may slow a bit or hold steady. At this time, only a few
rivers remain in flood, most significantly the Choctawhatchee
River near Bruce which should remain in moderate flood stage
through late week. Outside of these few rivers, flooding will not
be a concern, even with rain chances on the rise by mid week. The
only exceptions will be if an isolated storm gets pinned over a
basin for an extended period of time. This would be most likely on
Wednesday.
More specific stage information, as well as the latest river
forecasts can be found at the following link:
http:/goo.gl/Lpg4a1
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 93 74 90 73 90 / 40 20 40 20 60
Panama City 89 76 87 76 87 / 30 10 20 10 30
Dothan 95 74 89 72 90 / 20 20 50 20 60
Albany 95 73 89 73 89 / 20 20 40 30 60
Valdosta 96 74 90 73 89 / 30 20 50 30 60
Cross City 93 73 89 73 88 / 30 30 30 20 40
Apalachicola 89 75 87 75 86 / 20 10 20 10 30
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM...Wool
SHORT TERM...Harrigan
LONG TERM...Moore/Harrigan
AVIATION...Wool
MARINE...Harrigan
FIRE WEATHER...Wool
HYDROLOGY...Harrigan
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
111 AM EDT TUE JUL 30 2013
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 251 PM EDT MON JUL 29 2013
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW CONFLUENT NW FLOW
ALF OVER THE WRN GRT LKS BTWN SLOWLY DEPARTING CUTOFF LO JUST S OF
JAMES BAY AND AN UPR RDG OVER MN. THE ARRIVAL OF SFC HI PRES/ACYC
FLOW AND DRIER AIRMASS SHOWN ON THE 12Z INL RAOB ARE BRINGING A
MOSUNNY DAY TO THE CWA. LOOKING UPSTREAM...A SHRTWV IS MOVING INTO
THE NRN PLAINS IN THE WSW FLOW ALF BTWN THE UPR RDG OVER MN AND A
TROF OVER SW CANADA. THERE ARE SOME SHRA/TS ASSOCIATED WITH THIS
FEATURE...AND SOME CLDS WELL IN ADVANCE OF THE SHRA ARE SPILLING
INTO MN.
MAIN FCST CONCERNS IN THE SHORT TERM ARE MIN TEMPS TNGT AND THE CHC
FOR SOME SHRA ON TUE.
TNGT...UPR RDG AXIS IS PROGGED TO DRIFT W-E OVER UPR MI TNGT.
FOLLOWING THE PASSAGE OF THE UPR RDG...SOME MSTR IN ADVANCE OF
SHRTWV MOVING INTO MN IS FCST TO SPREAD INTO THE WRN CWA. IN CONCERT
WITH INCRSG WSW FLOW AT H925 ON THE BACK SIDE OF RETREATING SFC HI
PRES TO THE E...THE FALL OF TEMP OVER THE NW PORTIONS OF THE CWA
SHOULD BE HELD IN CHECK A BIT. THE BEST CHC FOR MIN TEMPS FALLING
FARTHER INTO THE 40S WL BE OVER THE INTERIOR SCENTRAL AND E...WHERE
THE CLDS WL ARRIVE LATEST CLOSER TO THE RETREATING HI.
TUE...A NUMBER OF MODELS GENERATE SOME MAINLY LGT PCPN OVER UPR MI
AS SHRTWV DRIFTS TO THE E AND INTERACTS WITH MODEST RETURN OF
SOMEWHAT HIER H85 THETA E. SUSPECT THE BEST CHC FOR SOME SHRA WL BE
IN THE AFTN WITH DAYTIME HEATING AND SOME LLVL CNVGC ON LK BREEZE
BNDRYS. SYNOPTIC SCALE SW FLOW SHOULD LIMIT INLAND PENETRATION OF
BREEZE OFF LK SUP. SINCE MODEL FCST SDNGS CONTINUE TO EXHIBIT
RELATIVELY WARM MID LVLS TEMPS/SOME CAPPING AOA H7/MARGINAL MID LVL
LAPSE RATES...WENT NO HIER THAN SCHC POPS AND KEPT OUT THE MENTION
OF TS FOR NOW WITH LIMITED INSTABILITY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 344 PM EDT MON JUL 29 2013
WE WILL START THIS LONG TERM PERIOD OUT WITH WESTERLY FLOW AT
500MB...WITH A RIDGE STUCK ACROSS THE SOUTHERN U.S. AND THE NEXT OF
A SERIES OF LOWS SET UP ACROSS MANITOBA.
THE 500MB LOW OVER MANITOBA WILL SHIFT ACROSS WESTERN AND CENTRAL
ONTARIO WEDNESDAY AS THE SFC RIDGE OVERHEAD EXITS TO THE SE. 850MB
TEMPS IN DECENT WAA BEHIND THE RIDGE SHOULD RISE TO AROUND 13C
BEFORE COLD FRONT SWEEPS IN FROM THE WNW DURING THE AFTERNOON AND
EARLY EVENING HOURS. TIMING LOOKS TO BE SIMILAR WITH THE AVAILABLE
MODEL GUIDANCE...WITH SHOWERS AND THUNDERSTORMS REMAINING MAINLY TO
OUR W OR OVER LAKE SUPERIOR THROUGH 12Z WEDNESDAY...AROUND 0.25IN
OVER THE W TIER OF COUNTIES BY 18Z...AND CENTRAL AND E DURING THE
MID TO LATE AFTERNOON HOURS. THERE ARE A COUPLE OF OUTLIERS. THE
29/12Z REGIONAL WRF AND CANADIAN RUNS WERE EITHER TOO STRONG OR TOO
WEAK WITH THE SHORTWAVES ROTATING THROUGH...AS THE 500MB TROUGH
BEGINS TO SWING INTO UPPER MI ON WEDNESDAY. VARIABLE PRECIPITATION
OUTPUTS OF NEARLY NOTHING TO AROUND AN INCH WERE THE RESULT. THE WRF
AND CANADIAN RUNS WERE EXCLUDED FROM MUCH OF THIS FCST...GIVEN THE
LOWER CONFIDENCE IN EITHER SOLUTION.
EXPECT THE COLD FRONT TO BE OVER FAR EASTERN UPPER MI BY 06Z
THURSDAY...WITH COOLER AIR FILTERING IN FROM THE NW ONCE AGAIN.
850MB TEMPS SHOULD FALL TO AROUND 8C BY DAYBREAK THURSDAY...WITH
LOWS NEAR 50F OVER THE W HALF OF UPPER MI WITH W WINDS HOVERING NEAR
10KTS.
NO REAL WARM UP IS EXPECTED FOR THURSDAY THROUGH THE UPCOMING
WEEKEND AS A SERIES OF DISTURBANCES SWINGING IN FROM THE NW HELP
KEEP THEM IN CHECK. THERE COULD BE SOME POP UP AFTERNOON SHOWERS OR
EVEN A THUNDERSTORM THURSDAY AFTERNOON INLAND FROM LAKE
SUPERIOR...AS ANOTHER SHORTWAVE ROTATES AROUND THE MAIN 500MB LOW
STUCK NEAR AND ACROSS HUDSON BAY. A SLIGHTLY MORE SIGNIFICANT SFC
TROUGH/500MB SHORTWAVE WILL SLIDE ACROSS FRIDAY AFTERNOON...WITH
ADDITIONAL CLOUD COVER...SHOWERS...AND INLAND POP UP THUNDERSTORMS.
YET ANOTHER ROUND OF SHOWERS WILL BE POSSIBLE SATURDAY...ALTHOUGH
LIKELY FARTHER EAST AS THE ENTIRE SYSTEM SHIFTS EASTWARD AND THE SFC
RIDGE BEGINS TO SHIFT IN. EXPECT DRY WEATHER SUNDAY AS THE SFC HIGH
PUSHES OVERHEAD...EVEN THROUGH NW FLOW LINGERS ALOFT. WITH THE
29/12Z ECMWF SHOWING 850MB TEMPS ON AROUND 7C AND LIGHT N
WINDS...60S AND LOW 70S STILL LOOK REASONABLE FOR HIGH TEMPS. AS FOR
DAY 7/MONDAY...THE SFC HIGH DOES NOT LOOK TO MOVE MUCH...BUT A WAVE
SLIDING THROUGH THE NW FLOW COULD BRING A PARTLY CLOUDY SKY TO THE W
WITH A FEW SHOWERS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 110 AM EDT TUE JUL 30 2013
VFR CONDITIONS WILL PREVAIL THRU THE FCST PERIOD AT KIWD/KCMX/KSAW.
A DISTURBANCE CURRENTLY OVER THE NRN PLAINS WILL PASS ACROSS THE
UPPER GREAT LAKES TODAY...BRINGING LOWER CLOUDS DOWN TO AROUND 5KFT
ALONG WITH THE POSSIBILITY OF A FEW -SHRA. INCLUDED VCSH DURING THE
MORNING/EARLY AFTN AT KIWD AS THERE IS SOME MODEL AGREEMENT FOR
ISOLD/SCT -SHRA TO REACH WRN UPPER MI. AT KCMX/KSAW...CONFIDENCE IS
LOWER THAT ANY SHRA WILL OCCUR AT OR IN THE VCNTY AS DISTURBANCE
WILL BE WEAKENING. SO...NO PCPN WAS MENTIONED FOR NOW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 251 PM EDT MON JUL 29 2013
EXPECT WINDS NO HIER THAN 20 KTS THIS FORECAST PERIOD WITH WEAK PRES
GRADIENT DOMINATING THE UPPER GREAT LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...ROLFSON
MARINE...KC
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1225 AM CDT TUE JUL 30 2013
.AVIATION.../06Z TAF ISSUANCE/
AN APPROACHING AREA OF LOW PRESSURE IN THE CENTRAL/EASTERN DAKOTAS
WILL BRING INCREASING LOW/MID LEVEL CLOUD COVER AND -SHRA ACROSS
NE MINNESOTA AND NW WISCONSIN EARLY THIS MORNING WHICH MAY
RESULT IN ISOLATED MVFR CIGS. THE CLOUD COVER WILL BEGIN TO SCATTER
AND/OR MOVE OUT OF THE REGION LATE THIS MORNING.
WHILE VFR CONDITIONS ARE IN THE FORECAST FOR THIS AFTERNOON AND
EVENING...A COLD FRONT WILL SET UP ACROSS NE MINNESOTA AND COULD
RESULT IN SOME -TSRA FOR THE KINL/KHIB/KBRD AREAS LATE IN THE
AFTERNOON AND/OR THE EVENING. ANY -TSRA COULD RESULT IN BRIEF MVFR
CIGS/VSBYS.
.PREV DISCUSSION... /ISSUED 848 PM CDT MON JUL 29 2013/
UPDATE...
AT 845PM/145Z...SURFACE HIGH PRESSURE WAS CENTERED NEAR THE
SOUTHERN GREAT LAKES. A TROUGH OF LOW PRESSURE WAS ORIENTATED FROM
NORTH TO SOUTH THROUGH CENTRAL MANITOBA THROUGH THE CENTRAL
DAKOTAS. THERE WERE SPRINKLES & LIGHT RAIN SHOWERS SOUTH OF THE
BRAINERD LAKES REGION AND HINCKLEY AREAS...WHICH WAS ASSOCIATED
WITH MID LEVEL CLOUDS WITH A PASSING WEAK SHORTWAVE. THERE WAS A
MUCH STRONGER SHORTWAVE IN NORTH CENTRAL NORTH DAKOTA HEADING
EAST. SHOWERS AND STORMS WERE MOVING THROUGH SOUTHERN MANITOBA AND
EASTERN NORTH DAKOTA AHEAD OF THE APPROACHING TROUGH. MUCH OF THE
NORTHLAND HAD PARTLY TO MOSTLY CLEAR SKIES...EXCEPT FOR MOSTLY
CLOUDY SKIES ACROSS THE SOUTHERN FRINGE OF THE FORECAST AREA NEAR
THE SHOWERS WITH THE WEAK SHORTWAVE. MOSTLY TO FULLY CLOUDY SKIES
COVERED MUCH OF EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA...AND
THOSE CLOUDS WERE HEADING EAST TOWARDS THE NORTHLAND. THE
NORTHLAND HAD TEMPERATURES RANGING FROM THE MID 50S TO UPPER 60S.
BASED ON THE LATEST TRENDS AND HIGH RESOLUTION MODELS...IT APPEARS
THE PREVIOUS FORECAST NEEDED SIGNIFICANT TWEAKS TO INCREASE CLOUD
COVER AND PCPN CHANCES FOR LATER TONIGHT AND INTO TUESDAY MORNING.
THE RAP13 AND HRRR ARE INDICATING THAT THERE WILL BE A LOT OF
INCREASING LOW/MID LEVEL HUMIDITY WITH THE LIGHT SOUTHERLY FLOW AS
THE TROUGH APPROACHES TONIGHT. THIS SHOULD RESULT IN INCREASING
CLOUD COVER. THOSE MODELS ARE ALSO INDICATING SCATTERED SHOWERS
WILL DEVELOP OVER MUCH OF THE NORTHLAND BY LATE TONIGHT AND THEN
BEGIN TO TAPER OFF AND/OR MOVE OUT OF THE NORTHLAND LATER TUESDAY
MORNING. THERE SEEMS TO BE LITTLE SUPPORT IN CAPE AND SHEAR IN THE
MODELS TO CONTINUE CARRYING ISOLATED THUNDER THROUGH THE
NIGHT...SO I ONLY FORECAST RAIN SHOWERS.
I ALSO INCREASED THE LOW TEMPERATURES A BIT BECAUSE OF THE
EXPECTED INCREASE IN CLOUD COVER.
PREV DISCUSSION... /ISSUED 626 PM CDT MON JUL 29 2013/
AVIATION.../00Z TAF ISSUANCE/
THERE WILL BE INCREASING LOW/MID LEVEL MOISTURE THIS EVENING AND
OVERNIGHT ACROSS NE MINNESOTA AND NW WISCONSIN WITH THE LIGHT
SOUTHERLY FLOW AHEAD OF AN APPROACHING TROUGH OF LOW PRESSURE
CURRENTLY IN THE DAKOTAS. THIS INCREASING MOISTURE WILL LIKELY
RESULT IN A PERIOD OF MVFR CIGS FOR KINL/KBRD/KHIB/KDLH/KHYR LATER
TONIGHT AND THROUGH PART OF TUESDAY MORNING BEFORE SCATTERING OR
MOVING OUT OF THE REGION LATE TUESDAY MORNING OR BY NOON. THERE
COULD BE SOME LIGHT RAIN SHOWERS DURING THIS PERIOD TOO. THE MVFR
CIGS SHOULD DEVELOP AT KINL/KBRD LATE THIS EVENING...AND THEN
SPREAD EAST TO KHIB/KDLH/KHYR LATE TONIGHT. VFR CONDITIONS ARE
LIKELY ACROSS THE REGION TUESDAY AFTERNOON.
PREV DISCUSSION... /ISSUED 322 PM CDT MON JUL 29 2013/
SHORT TERM...TONIGHT...
HIGH PRESSURE OVER THE GREAT LAKES WILL CONTINUE TO MOVE TO THE EAST
TONIGHT BRINGING SOUTHERLY WINDS AND MILDER CONDITIONS TO THE
NORTHLAND TONIGHT. TEMPERATURES WILL BE MAINLY IN THE LOWER 50S
OVERNIGHT. A SHORTWAVE WILL APPROACH FROM THE NORTHERN GREAT PLAINS
LATE TONIGHT AND BRING A CHANCE OF SHOWERS AND SOME THUNDERSTORMS TO
THE WESTERN PART OF THE FORECAST AREA...MAINLY AROUND MIDNIGHT. HIGH
RESOLUTION MODELS TRENDING A LITTLE FASTER BRINGING IN THE
PRECIPITATION AFTER 4Z FROM THE BRAINERD LAKES REGION TO THE
BORDERLAND. RAINFALL AMOUNTS LOOK TO BE UNDER A TENTH OF AN INCH BY
TUESDAY MORNING.
LONG TERM...TUESDAY THROUGH SATURDAY...
WESTERLY FLOW ALOFT TUESDAY WILL CARRY A WEAK MID LVL SHORTWAVE TROF
ACROSS THE REGION WITH SCTD LIGHT PRECIP. THE UPPER SHORTWAVE TROF
WILL OUTRUN THE LOW LVL FRONTAL SYSTEM. THE ASSOCIATED LOW LVL
FRONTAL SYSTEM WILL ENTER THE REGION TUESDAY NIGHT AS REFLECTED IN
THE LOW LVL THETAE FIELDS AND A DISTINCT SHIFT TO NW BDRY LAYER
FLOW. THIS FRONTAL PASSAGE WILL BE ACCOMPANIED BY A HIGHER PROB OF
PRECIP AS FRONTAL CONVERGENCE COMBINES WITH A STRONGER SHORTWAVE
ALOFT AND A SECONDARY PWAT AXIS. THIS FROPA WILL HERALD THE
AMPLIFICATION OF THE UPPER FLOW WEDNESDAY AFTN WHICH WILL CONTINUE
INTO THE WEEKEND. AS UPPER FLOW DEEPENS AND MEAN LAYER RH INCREASES
THUR/FRI AN OPPORTUNITY FOR SHOWERS WILL ARISE. NOT CONFIDENT ON HOW
FAR SOUTH THE POPS WILL OCCUR. HAVE STARTED WITH ARROWHEAD AND NRN
WISC..SPREADING INTO SERN CWA FRIDAY. LOW LVL THERMAL FIELDS SUGGEST
ANOTHER COLD FRONT WILL SWEEP ACROSS THE REGION FRIDAY. LARGE SFC
HIGH WILL MOVE FROM MANITOBA INTO NORTHLAND SATURDAY AND EARLY
SUNDAY. THE SFC HIGH IS FCST TO SHIFT EAST OF THE REGION SUNDAY
EVENING. A SLIGHT CHC THAT SOME PRECIP AMY ARRIVE LATE SUNDAY OVER
SWRN CORNER OF CWA IN RESPONSE TO WARM ADVECTION REGIME FROM NRN
PLAINS SYSTEM. TEMPS WILL RUN BLO CLIMO FOR MOST OF THIS PERIOD.
&&
.POINT TEMPS/POPS...
DLH 58 72 56 73 / 50 60 10 10
INL 55 71 53 71 / 50 10 10 20
BRD 59 76 56 76 / 60 40 0 10
HYR 59 75 54 75 / 30 60 10 10
ASX 59 73 56 73 / 30 60 10 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...DAP
LONG TERM....CLC
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
401 AM CDT TUE JUL 30 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT TUE JUL 30 2013
TODAY AND TONIGHT...DENSE FOG WOULD APPEAR TO BE VERY SHALLOW
THIS MORNING WITH THE MOON VISIBLE AT KLBF AND NEDOR SHOWING IT
LIFTING AT KLXN. SO WE WOULD EXPECT A RAPID CLEARING AFTER SUNRISE
IN SOME AREAS AS SATELLITE SHOWS AREAS OF STRATUS AT THE SAME TIME
WHICH WOULD SLOW THE LIFTING PROCESS.
A WEAK AND DECAYING MCS ACROSS NWRN NEB/SWRN SD THIS MORNING IN
COMBINATION WITH A WEAK DISTURBANCE OVER ERN COLO COULD PERHAPS
SPREAD ISOLATED SHOWERS AND THUNDERSTORMS INTO WRN NEB.
THE HRRR THEN SHOWS CONVECTIVE DESTABILIZATION ACROSS SWRN NEB BY
20Z WHICH IS PROBABLY AN HOUR OR TWO TOO FAST. THE MAIN IMPULSE
WOULD APPEAR TO BE DROPPING SOUTHEAST THROUGH NERN WY/WRN SD AT
20Z...STILL HOURS AWAY FROM THE FCST AREA. A MCS IS EXPECTED TO
DEVELOP OUT OF THE STORMS FIRING ACROSS THE NRN HIGH PLAINS WHICH
SHOULD SWEEP THRU NRN NEB OVERNIGHT. THE MCS SHOULD REMAIN MOSTLY
ALONG AND NORTH OF HIGHWAY 20.
TEMPERATURES TODAY ARE EXPECTED TO RISE INTO THE LOW TO MID 80S
IN MOST AREAS GIVEN THE CONTINUED SOUTH AND SOUTHEAST WINDS
CIRCULATING AROUND HIGH PRESSURE CENTERED OVER THE MIDWEST. THE
ENSUING WARM AIR ADVECTION FUELING THE MCS TONIGHT SHOULD KEEP
SKIES MOSTLY CLEAR SOUTH OF THE CONVECTIVE COMPLEX. THE NAM12
HINTS AT A BANK OF STRATUS FILLING IN ACROSS NWRN NEB IN THE WAKE
OF THE MCS AROUND 12Z.
SEVERE WEATHER POTENTIAL WITH THE THUNDERSTORMS THIS AFTERNOON
AND TONIGHT IS LIMITED TO 5 PERCENT OR ISOLATED WITH THE BEST
INSTABILITY AND 40 TO 50 KT 1 TO 6 KM SHEAR ACROSS NRN NEB MOSTLY
ASSOCIATED WITH THE DEVELOPING MCS. MODEL INDICATIONS SUGGEST THE
BLACK HILLS COULD BE THE GENESIS FOR A CLUSTER OF STORMS FORMING
LATE IN THE AFTERNOON WHICH WOULD MOVE EAST SOUTHEAST TOWARD
KVTN-KANW-KONL DURING THE EVENING AND OVERNIGHT. THIS IN TURN
COULD CERTAINLY INCREASE THE SEVERE WEATHER POTENTIAL IN THOSE
AREAS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 400 AM CDT TUE JUL 30 2013
WEDNESDAY MORNING LINGER SHOWERS WILL BE POSSIBLE ACROSS PORTIONS
OF CENTRAL/NORTH CENTRAL NEB. THEN BREAKS IN THE CLOUDS SHOULD
HELP TO PUSH HIGHS INTO THE 80S. LATE IN THE DATE MODELS IN
AGREEMENT WITH A BOUNDARY STRETCHED FROM WEST CENTRAL KS
NORTHEAST INTO CENTRAL NEB AND ON TOWARDS THE WESTERN GREAT
LAKES. THUNDERSTORMS WILL BE POSSIBLE ALONG THE SLOW MOVING
BOUNDARY...HOWEVER IMPACT TO THE CWA IN QUESTIONS. THE LATEST NAM
AND GFS HAVE PUSHED THE BOUNDARY JUST SE OF THE CWA BY PEAK
HEATING...HOWEVER THE EC AND GEM DO DEVELOP ACTIVITY IN THE SE
CWA. WILL TREND DOWN WITH POPS...ALTHOUGH STILL RETAIN SLGHT CHC
IN THE FAR SE ZONES. MORE OF A FOCUS WILL BE THE NEXT SHORT WAVE
CROSSING THE ROCKIES. THIS WAVE SHOULD ALLOW DEVELOPMENT ON THE
HIGHER TERRAIN WITH FLOW TO PUSH THIS INTO THE PANHANDLE AND
WESTERN NEBRASKA OVERNIGHT.
THURSDAY WILL SEE YET ANOTHER SHORT WAVE TO PUSH ACROSS THE AREA.
MODELS CONTINUE TO SHOW GOOD INSTABILITY WITH DECENT SHEAR...ALSO
WILL SEE A SURF LOW DEVELOP NEAR NE CO. ANY ACTIVITY DEVELOPING IN
THE EVENING FROM PEAK HEATING WILL LIKELY BE SUSTAINED BY A 30 TO
40K LL JET. LOW FREEZING LEVEL WITH STEEP LAPSE RATE SHOULD RESULT
IN A FEW STRONG TO EVEN SEVERE STORMS...WITH HAIL THE MAIN THREAT.
FRIDAY WILL SEE AN UPPER LEVEL LOW COME ONSHORE TO THE PAC
NW...THIS WILL FLATTEN THE RIDGE AND PUSH IT EASTWARD. INITIALLY
THOUGHT THERE COULD BE A WARM UP...HOWEVER MODELS CONTINUE TO
BRING GOOD MOISTURE AROUND THE RIDGE...RESULTING IN MORE CLOUDS
THAN SUN. FORECAST RESULTS IN BELOW NORMAL HIGHS...WHICH IS CLOSE
TO MOS GUIDANCE.
LITTLE CHANGES THROUGH THE WEEKEND FOR THE AREA...AS RIDGE REMAINS
TO THE SOUTH AND LOW WILL TRAVERSE ACROSS THE US/CAN BORDER. FLOW
WILL CONTINUE TO BE NORTHWESTERLY TO ZONAL...AND MODELS CONTINUE
TO BRING WAVE AFTER WAVE ACROSS THE AREA. QPF MAY NOT BE
SIGNIFICANT...HOWEVER WILL NEED TO CONTINUE TO MENTION IN NEARLY
EVERY PERIOD PENDING TIMING OF THE WAVES. TEMPS WILL GENERALLY BE
BELOW NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1130 PM CDT MON JUL 29 2013
THE 06Z TAF ISSUANCE FOR KLBF AND KVTN. IFR CONDITIONS ARE
FORECAST FOR KLBF UNTIL 14Z. LOWEST CIGS AND VSBYS FAVORED TO
OCCUR FROM 09Z-13Z. IFR WITH SOME DEVELOPING LIFR CONDITIONS IN
CENTRAL AND SOUTH CENTRAL NEBRASKA WILL AFFECT PORTIONS OF WESTERN
NEBRASKA OVERNIGHT INTO EARLY TUESDAY. CIGS AND VSBY TO QUICKLY
LIFT/IMPROVE AFTER 14Z TO VFR. CURRENT VFR CONDITIONS AT KVTN
SHOULD REMAIN PREVAILING OVERNIGHT. HAVE CONTINUED A TEMPO FOR 5SM
BR 09Z-13Z. LOW STRATUS LIFTING NORTHWEST TOWARD KANW MAY BE ABLE
TO REACH KVTN AND WILL NEED TO MONITOR OVERNIGHT. ISOLATED/SCATTERED
STORM DEVELOPMENT POSSIBLE TUES AFTERNOON/EVENING...BUT WILL NOT
INCLUDE ATTM WITH MODEL DIFFERENCES IN TIMING LEADING TO LOW
CONFIDENCE.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM CDT /9 AM MDT/ THIS MORNING FOR
NEZ038-059-069>071.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...ROBERG
AREA FORECAST DISCUSSION
NWS RALEIGH NC
259 AM EDT TUE JUL 30 2013
.SYNOPSIS...
A STATIONARY FRONT WILL LINGER OVER SOUTHEAST NORTH CAROLINA TODAY
AS WEAK HIGH PRESSURE BUILDS INTO THE MID ATLANTIC FROM THE WEST. A
MORE AMPLIFIED PATTERN OF CYCLONIC FLOW ALOFT WILL PREVAIL ON
WEDNESDAY AND THURSDAY...WITH ANOTHER WEAK COLD FRONT PROGRESSING
INTO THE CAROLINAS FROM THE NORTHWEST THURSDAY NIGHT.
&&
.NEAR TERM /TONIGHT/...
AS OF 945 PM MONDAY...
THE LATEST SURFACE ANALYSIS SHOWED A SURFACE FRONT NEARLY STATIONARY
OVER THE SOUTHEAST PART OF CENTRAL NORTH CAROLINA. AS OUTFLOW FROM
DEEP CONVECTION ALONG THE COAST MOVED NORTHWEST...THIS SUPPORTED
SOME SHORT-LIVED STRENGTHENING OF SHOWERS AND THUNDERSTORMS THAT
DEVELOPED IN VICINITY OF KFAY AND KMEB. THESE SHOWERS AND STORMS
HAVE CERTAINLY WANED DURING THE MID-EVENING HOURS...AND BUFR
SOUNDINGS FROM BOTH THE NAM AND THE GFS...ALONG WITH OUTPUT FROM THE
RUC AND MOST RECENT HRRR WRF...SHOW THAT THE POTENTIAL FOR DEEP
CONVECTION OVERNIGHT SHOULD BE LIMITED. 850MB SUBSIDENCE IS FORECAST
BY THE RUC OVERNIGHT...AND THOSE BUFR SOUNDINGS INDICATE SLIGHT
WARMING AND RELAXING OF LAPSE RATES ALOFT OVERNIGHT. FOR THE REST OF
THE EVENING...MAINTAINED A SLIGHT CHANCE OF A SHOWER OR THUNDERSTORM
SOUTH OF A LINE FROM ABOUT GOLDSBORO TO ROCKINGHAM...WITH A CHANCE
IN VICINITY OF KCTZ. OVERNIGHT...IN THE DEEPER MOISTURE SOUTH OF THE
FRONT...MAINTAINED A SLIGHT CHANCE OF A SHOWER ONLY OVER THE LATTER.
THE IR SATELLITE IMAGES SHOW PATCHES OF CI AND AC IN THE NORTHWEST
FLOW ALOFT BEHIND THE TROUGH AXIS. WHILE THE GFS BUFR SOUNDINGS ARE
VERY DRY ALOFT...THE NAM SHOWS A NARROW VOLUME OF MOISTURE ALOFT AT
MOST SITES THROUGH THE OVERNIGHT HOURS. BASED ON THE SATELLITE
IMAGES...THE NAM MAY BE VERIFYING BEST...AND PARTLY CLOUDY
CONDITIONS ARE FORECAST ON AVERAGE FOR THE OVERNIGHT. ANTICIPATE THE
DEVELOPMENT OF SOME LOW CLOUDS AND PATCHY FOG ESPECIALLY OVER THE
SOUTHEAST PART OF CENTRAL NORTH CAROLINA OVERNIGHT...IN THE BETTER
MOISTURE AND WHERE SCATTERED SHOWERS OCCURRED DURING THE DAY AND
EARLY EVENING. LOWERED MINS A BIT ESPECIALLY TOWARD KTDF...AND
KHNZ...WHERE TEMPERATURES DURING THE EVENING WERE FALLING QUICKLY
AND READINGS NEAR 60 APPEARED LIKELY. IN FACT...A COUPLE OF UPPER
50S ARE POSSIBLE TOWARD THE VIRGINIA BORDER. OVERNIGHT LOWS IN THE
60S.
&&
.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
AS OF 225 PM MONDAY...
WITH ZONAL FLOW ALOFT AND HIGH PRESSURE TO OUR NORTH MOST OF THE
DAY...THE AFOREMENTIONED FRONT WILL REMAIN POSITIONED NEAR OR
PERHAPS A BIT FURTHER SOUTH THAN ITS CURRENT POSITION. WITH MOST OF
OUR CWA ON THE DRIER MORE STABLE SIDE OF THE BOUNDARY...FOR NOW THE
ONLY PLACE WE`LL CARRY SLIGHT CHANCE POPS DURING THE DAY WILL BE
ACROSS OUR FAR S/SE ZONES. HIGHS WILL ONCE AGAIN RANGE FROM THE MID
80S NW TO UPPER 80S SE...WHICH IS A DEGREE OR TWO BELOW NORMAL.
CLOUDS WILL BE ON THE INCREASE TUESDAY NIGHT AS THE SHORT WAVE
THAT`S CURRENTLY OVER THE CENTRAL PLAINS MOVES EAST AND APPROACHES
THE CAROLINAS. IF THIS SYSTEM SPEEDS UP...SOME LIGHT SHOWER ACTIVITY
MAY MOVE INTO OUR WESTERN ZONES BEFORE SUNRISE. WILL INCLUDE SLIGHT
CHANCE POPS ACROSS OUR WESTERN ZONES TUESDAY NIGHT TO ACCOUNT FOR
THIS POSSIBILITY. SLIGHTLY WARMER LOWS CAN BE EXPECTED DUE TO THE
ADDITIONAL CLOUD COVER...UPPER 60S NW TO LOWER 70S SE.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 259 AM TUESDAY...
THE PATTERN OF THE PAST 30-60 DAYS CONTINUES TO BE VERY PERSISTENT
AND WILL REMAIN SO THROUGH THE NEXT WEEK OR TWO.
A BROAD MID/UPPER TROUGH IS EXPECTED TO CONTINUE TO DIG SE ACROSS
FROM THE OHIO VALLEY INTO OUR REGION THURSDAY AND THURSDAY NIGHT.
THE MAIN COLD FRONT AGAIN SHOULD LAG WELL BEHIND THE PRE-FRONTAL
TROUGH THAT IS FORECAST TO BE IN THE LEE OF THE BLUE RIDGE BY
12Z/THU. IN ADDITION... THERE SHOULD BE RESIDUAL OUTFLOWS FROM THE
PREVIOUS NIGHTS CONVECTION IN OR NEAR THIS REGION TO BEGIN THURSDAY
AS WELL. STRONG SURFACE HEATING THURSDAY MAY BE HARD TO COME BY
GIVEN THE INCREASE OF PRECIPITABLE WATER VALUES TO AROUND 2 INCHES
LEADING TO PLENTY OF CLOUDINESS. HOWEVER... DIFFERENTIAL HEATING
WITHIN THE BREAKS OF THE CLOUDS SHOULD LEAD TO RAPID DESTABILIZATION
WITH DAYTIME HEATING. MIXED LAYER CAPES BETWEEN 1000 AND 1500 J/KG
ARE GENERALLY FORECAST OVER OUR REGION DURING THE AFTERNOON AND
EVENING... HIGHEST IN THE SOUTH AND EAST. SHOWERS AND THUNDERSTORMS
ARE LIKELY ANYTIME DURING THE DAY... BUT SHOULD BECOME MOST LIKELY
DURING THE AFTERNOON AND EVENING HOURS ALONG AND EAST OF THE
PRE-FRONTAL TROUGH AS IT SLOWLY PROGRESS SE INTO THE PIEDMONT...
THEN COASTAL PLAIN AND SANDHILLS IN THE EVENING. WHILE A WIDESPREAD
SEVERE THREAT IS NOT EXPECTED... ISOLATED STORMS MAY APPROACH SEVERE
CRITERIA GIVEN THE LIMITED SHEAR EXPECTED. LOCALLY HEAVY RAIN MAY BE
THE MAIN WEATHER HAZARD... ALONG WITH FREQUENTLY CG LIGHTNING
STRIKES. WE WILL CONTINUE THE LIKELY POP THURSDAY... FOCUSING ON THE
NW EARLY TO MID DAY... THEN ELSEWHERE BETWEEN 18Z AND 06Z/FRIDAY.
HIGHS THURSDAY SHOULD TOP OUT IN THE MID TO UPPER 80S EXCEPT LOWER
80S IN THE NW. LOWS THURSDAY NIGHT SHOULD BE IN THE MID 60S NW...
AND 70-73 ELSEWHERE UNDER MOSTLY CLOUDY SKIES AND DECREASING STORM
CHANCES BY 12Z/FRI.
FRIDAY THROUGH SATURDAY... THE AFOREMENTIONED COLD FRONT SHOULD
FINALLY OVERTAKE THE PRE-FRONTAL TROUGH OVER SOUTHEASTERN SECTIONS
OF NC BY EARLY FRIDAY. THIS IS WHERE A CHANCE OF SHOWERS AND
THUNDERSTORMS WILL LINGER FRIDAY. MOST OF OUR REGION SHOULD BE
DRIER... AND BECOMING LESS HUMID WITH THE NNE LOW LEVEL FLOW AND
DECREASE IN CLOUDINESS. HIGHS FRIDAY SHOULD BE IN THE MID TO UPPER
80S (MUCH LIKE THE TEMPERATURES WE EXPERIENCED SUNDAY). MOSTLY CLEAR
SKIES FRIDAY NIGHT WILL LEAD TO COMFORTABLE LOWS FOR EARLY AUGUST.
MOST GUIDANCE SUGGESTS LOWER TO MID 60S EXCEPT NEAR 70 IN THE SE
(ABOUT 4-8 DEG BELOW NORMAL). SATURDAY SHOULD BE LARGELY DRY AS THE
FRONT WASHES OUT ALONG THE COAST AND WEAK HIGH PRESSURE REMAINS
INLAND. MOSTLY SUNNY TO PARTLY CLOUDY WITH HIGHS IN THE MID 80S.
SUNDAY AND MONDAY... THE PATTERN REPEATS AGAIN. ANOTHER MID/UPPER
TROUGH IS FORECAST TO DIG SE INTO THE CENTRAL APPALACHIANS AND
EVENTUALLY OUR REGION BY MONDAY. THIS WILL ALLOW ANOTHER COLD FRONT
AND PRE-FRONTAL TROUGH/OUTFLOWS TO DRIVE CONVECTION CHANCES UP AGAIN
SUNDAY AFTERNOON THROUGH MONDAY. LOWS WILL CREEP BY UP TO 70+. HIGHS
SHOULD BE IN THE MID TO UPPER 80S BOTH DAYS.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 115 AM TUESDAY...
24-HR TAF PERIOD:
SUB-VFR VISBYS ASSOCIATED WITH FOG WILL BE POSSIBLE BETWEEN 07-12Z
THIS MORNING...PRIMARILY AT THE RDU/FAY/RWI TERMINALS ALONG AND
SOUTH OF A STALLED FRONT. OTHERWISE...EXPECT VFR CONDITIONS TO
PREVAIL THROUGH THE TAF PERIOD WITH LITTLE CHANCE FOR AFTERNOON
CONVECTION ASIDE FROM A SMALL PROBABILITY FOR AN ISOLD SHOWER OR
STORM AT THE FAY TERMINAL BETWEEN 20-00Z.
LOOKING AHEAD:
EXPECT AN INCREASING CHANCE FOR SHOWERS AND THUNDERSTORMS ACROSS
CENTRAL NC WED AFT/EVE AS UPPER LEVEL DISTURBANCES PROGRESS INTO THE
REGION FROM THE WEST...WITH A CONTINUED POTENTIAL FOR MORNING
FOG/STRATUS. MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED
THU AND PERHAPS INTO THU NIGHT AS A WEAK COLD FRONT APPROACHES FROM
THE WEST IN CYCLONIC FLOW ALOFT. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...DJF
SHORT TERM...NP
LONG TERM...BADGETT
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS RALEIGH NC
123 AM EDT TUE JUL 30 2013
.SYNOPSIS...
A STATIONARY FRONT WILL LINGER OVER SOUTHEAST NORTH CAROLINA TODAY
AS WEAK HIGH PRESSURE BUILDS INTO THE MID ATLANTIC FROM THE WEST. A
MORE AMPLIFIED PATTERN OF CYCLONIC FLOW ALOFT WILL PREVAIL ON
WEDNESDAY AND THURSDAY...WITH ANOTHER WEAK COLD FRONT PROGRESSING
INTO THE CAROLINAS FROM THE NORTHWEST THURSDAY NIGHT.
&&
.NEAR TERM /TONIGHT/...
AS OF 945 PM MONDAY...
THE LATEST SURFACE ANALYSIS SHOWED A SURFACE FRONT NEARLY STATIONARY
OVER THE SOUTHEAST PART OF CENTRAL NORTH CAROLINA. AS OUTFLOW FROM
DEEP CONVECTION ALONG THE COAST MOVED NORTHWEST...THIS SUPPORTED
SOME SHORT-LIVED STRENGTHENING OF SHOWERS AND THUNDERSTORMS THAT
DEVELOPED IN VICINITY OF KFAY AND KMEB. THESE SHOWERS AND STORMS
HAVE CERTAINLY WANED DURING THE MID-EVENING HOURS...AND BUFR
SOUNDINGS FROM BOTH THE NAM AND THE GFS...ALONG WITH OUTPUT FROM THE
RUC AND MOST RECENT HRRR WRF...SHOW THAT THE POTENTIAL FOR DEEP
CONVECTION OVERNIGHT SHOULD BE LIMITED. 850MB SUBSIDENCE IS FORECAST
BY THE RUC OVERNIGHT...AND THOSE BUFR SOUNDINGS INDICATE SLIGHT
WARMING AND RELAXING OF LAPSE RATES ALOFT OVERNIGHT. FOR THE REST OF
THE EVENING...MAINTAINED A SLIGHT CHANCE OF A SHOWER OR THUNDERSTORM
SOUTH OF A LINE FROM ABOUT GOLDSBORO TO ROCKINGHAM...WITH A CHANCE
IN VICINITY OF KCTZ. OVERNIGHT...IN THE DEEPER MOISTURE SOUTH OF THE
FRONT...MAINTAINED A SLIGHT CHANCE OF A SHOWER ONLY OVER THE LATTER.
THE IR SATELLITE IMAGES SHOW PATCHES OF CI AND AC IN THE NORTHWEST
FLOW ALOFT BEHIND THE TROUGH AXIS. WHILE THE GFS BUFR SOUNDINGS ARE
VERY DRY ALOFT...THE NAM SHOWS A NARROW VOLUME OF MOISTURE ALOFT AT
MOST SITES THROUGH THE OVERNIGHT HOURS. BASED ON THE SATELLITE
IMAGES...THE NAM MAY BE VERIFYING BEST...AND PARTLY CLOUDY
CONDITIONS ARE FORECAST ON AVERAGE FOR THE OVERNIGHT. ANTICIPATE THE
DEVELOPMENT OF SOME LOW CLOUDS AND PATCHY FOG ESPECIALLY OVER THE
SOUTHEAST PART OF CENTRAL NORTH CAROLINA OVERNIGHT...IN THE BETTER
MOISTURE AND WHERE SCATTERED SHOWERS OCCURRED DURING THE DAY AND
EARLY EVENING. LOWERED MINS A BIT ESPECIALLY TOWARD KTDF...AND
KHNZ...WHERE TEMPERATURES DURING THE EVENING WERE FALLING QUICKLY
AND READINGS NEAR 60 APPEARED LIKELY. IN FACT...A COUPLE OF UPPER
50S ARE POSSIBLE TOWARD THE VIRGINIA BORDER. OVERNIGHT LOWS IN THE
60S.
&&
.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
AS OF 225 PM MONDAY...
WITH ZONAL FLOW ALOFT AND HIGH PRESSURE TO OUR NORTH MOST OF THE
DAY...THE AFOREMENTIONED FRONT WILL REMAIN POSITIONED NEAR OR
PERHAPS A BIT FURTHER SOUTH THAN ITS CURRENT POSITION. WITH MOST OF
OUR CWA ON THE DRIER MORE STABLE SIDE OF THE BOUNDARY...FOR NOW THE
ONLY PLACE WE`LL CARRY SLIGHT CHANCE POPS DURING THE DAY WILL BE
ACROSS OUR FAR S/SE ZONES. HIGHS WILL ONCE AGAIN RANGE FROM THE MID
80S NW TO UPPER 80S SE...WHICH IS A DEGREE OR TWO BELOW NORMAL.
CLOUDS WILL BE ON THE INCREASE TUESDAY NIGHT AS THE SHORT WAVE
THAT`S CURRENTLY OVER THE CENTRAL PLAINS MOVES EAST AND APPROACHES
THE CAROLINAS. IF THIS SYSTEM SPEEDS UP...SOME LIGHT SHOWER ACTIVITY
MAY MOVE INTO OUR WESTERN ZONES BEFORE SUNRISE. WILL INCLUDE SLIGHT
CHANCE POPS ACROSS OUR WESTERN ZONES TUESDAY NIGHT TO ACCOUNT FOR
THIS POSSIBILITY. SLIGHTLY WARMER LOWS CAN BE EXPECTED DUE TO THE
ADDITIONAL CLOUD COVER...UPPER 60S NW TO LOWER 70S SE.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
AS OF 250 PM MONDAY...
OVERALL THE LONG TERM PERIOD WILL FEATURE A MEAN TROUGH ACROSS THE
EASTERN CONUS WITH A SERIES OF SHORTWAVES/WEAK FRONTS PROGRESSING
THROUGH THE AREA. THIS SET-UP WILL KEEP THE SUMMER HEAT AT BAY WHILE
PROVIDING PERIODS OF INCREASED SHOWER AND THUNDERSTORM ACTIVITY.
THIS NEXT UPPER TROUGH/SURFACE COLD FRONT IS PROGGED TO APPROACH AND
SLOWLY CROSS THE REGION WEDNESDAY INTO THURSDAY. MODELS HAVE SHOWN
SOMEWHAT OF A SLOWING TREND THE PAST COUPLE OF DAYS (ESPECIALLY THE
GFS)...BUT FOR NOW IT STILL APPEARS THAT THE BEST CHANCE OF RAIN
WILL OCCUR LATE WEDNESDAY INTO THURSDAY (ALTHOUGH CURRENT GFS SHOWS
THE SIGNIFICANT PRECIP ASSOCIATED WITH THE FRONT HOLDING OFF UNTIL
THURSDAY AND PERSISTING MORE INTO FRIDAY). NEVERTHELESS...WILL STILL
SHOW POPS INCREASING FROM WEST TO EAST ON WEDNESDAY AND THEN
GRADUALLY DECREASING IN THE SAME FASHION LATE THURSDAY.
BY FRIDAY...THE FRONT SHOULD STALL/WASH OUT SOMEWHERE NEAR THE
REGION. OVERALL...THE ECMWF HAS BEEN FAIRLY CONSISTENT WITH PUSHING
IT SOUTH/EAST OF THE FORECAST AREA WHICH WOULD RESULT IN MOSTLY DRY
CONDITIONS FOR CENTRAL NC...WHILE THE GFS IS SLOWER WITH THE
EASTWARD PROGRESSION (SEE ABOVE PARAGRAPH). HOWEVER...GIVEN THE TIME
OF THE YEAR AND RECENT EVENTS...WILL MAINTAIN AT LEAST A MENTION OF
PRECIP FOR FRIDAY AND SATURDAY...ESPECIALLY ON FRIDAY AND MOSTLY
ACROSS THE EASTERN/SOUTHERN PORTIONS OF THE FORECAST AREA...WITH ANY
ACTIVITY BEING MOSTLY DIURNAL IN NATURE. YET ANOTHER NEXT SYSTEM
WILL APPROACH THE AREA LATE IN THE WEEKEND/EARLY NEXT WEEK (ALTHOUGH
TIMING IS IN QUESTION AT THIS TIME).
TEMPS WILL ULTIMATELY BE DEPENDENT ON THE EXACT TIMING/EXTENT OF ANY
PRECIP THAT OCCURS...BUT SHOULD LARGELY BE NEAR TO SLIGHTLY BELOW
NORMAL THROUGH THE PERIOD.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 115 AM TUESDAY...
24-HR TAF PERIOD:
SUB-VFR VISBYS ASSOCIATED WITH FOG WILL BE POSSIBLE BETWEEN 07-12Z
THIS MORNING...PRIMARILY AT THE RDU/FAY/RWI TERMINALS ALONG AND
SOUTH OF A STALLED FRONT. OTHERWISE...EXPECT VFR CONDITIONS TO
PREVAIL THROUGH THE TAF PERIOD WITH LITTLE CHANCE FOR AFTERNOON
CONVECTION ASIDE FROM A SMALL PROBABILITY FOR AN ISOLD SHOWER OR
STORM AT THE FAY TERMINAL BETWEEN 20-00Z.
LOOKING AHEAD:
EXPECT AN INCREASING CHANCE FOR SHOWERS AND THUNDERSTORMS ACROSS
CENTRAL NC WED AFT/EVE AS UPPER LEVEL DISTURBANCES PROGRESS INTO THE
REGION FROM THE WEST...WITH A CONTINUED POTENTIAL FOR MORNING
FOG/STRATUS. MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED
THU AND PERHAPS INTO THU NIGHT AS A WEAK COLD FRONT APPROACHES FROM
THE WEST IN CYCLONIC FLOW ALOFT. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...DJF
SHORT TERM...NP
LONG TERM...KRR
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1130 PM CDT MON JUL 29 2013
.UPDATE...
ISSUED AT 1130 PM CDT MON JUL 29 2013
CURRENT RADAR SHOWS LINE OF RAIN SHOWERS JUST EAST OF THE RRV AND
ALONG THE INTERNATIONAL BORDER STRETCHING SOUTHWARD TO SOUTHERN
CASS COUNTY. LINE IS MOVING AROUND 25 KTS AND EXPECT IT TO CLEAR
CWA BY AROUND 13Z. UPDATED TIMING OF SCATTERED SHOWERS ACROSS CWA.
WATER VAPOR SHOWING DECENT DRYING BEHIND WAVE AND SKIES MOSTLY
CLEAR ACROSS CNTRL AND WRN ND. WILL MENTION MIST IN TAFS BUT DO
NOT THINK VSBYS WILL BE LOW ENOUGH FOR A MENTION OF FOG IN GRIDS
WITH LACK OF SFC HIGH BRINGING CALM WINDS.
UPDATE ISSUED AT 930 PM CDT MON JUL 29 2013
CURRENT RADAR SHOWING LINE OF SHOWERS PARALLEL AND JUST WEST OF
RRV. CTG LIGHTNING HAS DECREASED AND ONLY STRIKE ON NLDN IS NOW IN
VICINITY OF VALLEY CITY. EXPECT THIS WILL DIE OFF IN THE NEXT 30
MIN OR SO AND HAVE WENT TO ALL SHOWERS FOR REMAINDER OF THE NIGHT.
MAIN FORECAST CHANGE IS SLOWING DOWN EASTWARD PROGRESSION AND ALSO
BEGINNING TO REMOVE POPS FROM SOUTHERN END OF LINE AS SHOWERS
PROGRESS EASTWARD. DO NOT LOOK FOR ANY SHOWERS ALONG SOUTHERN TIER
OF ZONES. ALSO PULLING POPS BEHIND LINE IN THE DVL BASIN UP
THROUGH TOWNER COUNTY. NO SIG CHANGES TO TEMPS ANTICIPATED.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 338 PM CDT MON JUL 29 2013
FORECAST CHALLENGES INCLUDE CONVECTIVE CHANCES TONIGHT THROUGH
TOMORROW NIGHT. GFS/NAM/ECMWF/GEM SYNOPTIC FIELDS IN GOOD OVERALL
AGREEMENT...BUT DIFFER SOMEWHAT WITH THE MESOSCALE DETAILS. WILL
USE THE RAP FOR THE ONGOING CONVECTION ACROSS CENTRAL ND THIS
EVENING AND TONIGHT...SHIFTING TO A MODEL BLEND FOR THE REMAINDER
OF THE SHORT-TERM.
20 UTC REGIONAL RADARS SHOW THE SHOWERS ACROSS NORTHEAST SD HAVE
BARELY MOVED INTO THE SOUTHERN VALLEY WITH PERHAPS A FEW SPRINKLES
FALLING ACROSS THE LAKES COUNTRY OF WEST CENTRAL MN. WILL KEEP 20
TO 30 POPS IN THESE AREAS THROUGH THE EARLY EVENING AFTER WHICH ANY
REMAINING ACTIVITY SHOULD DISSIPATE. IN ADDITION...THE ORIGINAL
LINE OF CONVECTION AHEAD OF THE SURFACE TROUGH THIS MORNING HAS
DISSIPATED AND GIVEN WAY TO A STRONGER LINE NOW STRETCHING FROM
NORTHWEST OF MINOT TO SOUTHWEST OF BISMARCK...MOVING TO THE EAST
AROUND 25 KTS. THESE THUNDERSTORMS ARE ALIGNED ALONG THE SURFACE
BOUNDARY NEAR THE AXIS OF GREATEST INSTABILITY. AS THE SHORT-WAVE
ALOFT PROPAGATES ACROSS EASTERN ND AND NORTHWEST MN THIS EVENING
AND OVERNIGHT...THESE STORMS WILL CONTINUE TO MOVE ACROSS ND/MN.
HOWEVER...INSTABILITY IS WEAK ALONG AND EAST OF THE VALLEY...SO
THE EXTENT TO WHICH THEY HOLD TOGETHER IS IN QUESTION. THE RAP
WITH SUPPORT FROM THE GFS/NAM DISSIPATE THESE STORMS EAST OF THE
VALLEY AND IF THIS VERIFIES...CURRENT POPS MAY BE TOO HIGH. GIVEN
HIGHER INSTABILITY TO THE WEST...SOME THUNDERSTORMS COULD BE STRONG
AND EVEN SEVERE ACROSS THE DEVILS LAKE BASIN. HOWEVER...NO SEVERE
CONVECTION IS EXPECTED ALONG AND EAST OF THE VALLEY.
MUCH OF TUESDAY SHOULD BE DRY AS THE REGION IS BETWEEN WEATHER
SYSTEMS...BUT SHOWER AND THUNDERSTORM CHANCES INCREASE AGAIN LATE
IN THE DAY AND OVERNIGHT AS A STRONG CANADIAN SHORT-WAVE AND
ASSOCIATED COLD FRONT MOVE ACROSS THE FORECAST AREA. THE HIGHEST
INSTABILITY WILL REMAIN ACROSS SD INTO SOUTHWEST MN...BUT MODELS
INDICATE MLCAPE UP TO 1500 J/KG MAINLY ALONG AND SOUTH OF THE I-94
CORRIDOR BY TUESDAY AFTERNOON. WITH THE APPROACHING COLD FRONT AND
50+ KTS OF 0 TO 6 KM BULK SHEAR ASSOCIATED WITH A 60 TO 80 KT 300
HPA JET STREAK...MODELS HINT AT A CONVECTIVE COMPLEX DEVELOPING
SOMEWHERE NEAR THE ND/SD BORDER. SPC DAY 2 CONVECTIVE OUTLOOK
SHOWS A SLIGHT RISK FOR SEVERE CONVECTION IN THIS AREA AND THIS
SEEMS REASONABLE. EXACT PLACEMENT OF ANY COMPLEX THAT DOES DEVELOP
IS UNCERTAIN AS IS THE EASTWARD EXTENT TO THE SEVERE POTENTIAL...
SO SOMETHING TO FINE-TUNE IN THE NEXT FORECAST PACKAGE IF POSSIBLE.
THERMAL RIDGE AXIS MOVES OVERHEAD IN FRONT OF THE COLD FRONT...SO
HIGHS TUESDAY WILL REACH THE UPPER 70S TO NEAR 80 DEGREES.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 338 PM CDT MON JUL 29 2013
WEDNESDAY AND THURSDAY WILL BE DRY WITH SURFACE HIGH PRESSURE
BUILDING ACROSS THE FORECAST AREA. TEMPERATURES WILL BE A BIT
COOLER WITH HIGHS IN THE 70S AND LOWS IN THE 50S. WINDS WILL BE
BREEZY FROM THE NORTHWEST WEDNESDAY BEFORE BECOMING LIGHT ON
THURSDAY AS THE PRESSURE GRADIENT RELAXES.
HIGH PRESSURE WILL REMAIN FROM MANITOBA INTO EASTERN NORTH DAKOTA
FRIDAY INTO SATURDAY KEEPING US DRY WITH TEMPERATURES REMAINING
NEARLY 10 DEGREES BELOW AVERAGE. HIGH PRESSURE MOVES EAST INTO THE
WESTERN GREAT LAKES REGION BY LATE SUNDAY ALLOWING NEXT SHORT WAVE
AND SURFACE LOW TO MOVE INTO THE NORTHERN PLAINS. THIS SYSTEM WILL
GIVE THE RISK OF SHOWERS AND THUNDERSTORMS SUNDAY TO EASTERN NORTH
DAKOTA AND PARTS OF WESTERN MINNESOTA...WHILE EASTERN FCST AREA WILL
REMAIN DRY. WILL GO WITH MOSTLY 30-40 POPS MONDAY AS SYSTEM MOVES
THROUGH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1130 PM CDT MON JUL 29 2013
SAT SHOWING CLEARING BEHIND LINE OF SHOWERS. WITH AROUND ONE
QUARTER TO ONE HALF INCH OF RAIN AND CLEARING BY EARLY
MORNING...WILL MENTION MVFR MIST AT DVL...GFK AND FAR. DO NOT
THINK CLOUDS WILL CLEAR IN TIME TO GET CLEARING SUFFICIENT FOR
MIST AT TVF AND BJI. FOR TOMORROW EVENING...WITH MODELS BACKING
OFF ON TIMING OF PRECIP INTO THE WEST...NOT ENOUGH CONFIDENCE TO
PUT TSTMS IN THE LAST SIX HOURS OF 06Z TAFS. DVL OR FAR WOULD HAVE
BEST CHANCE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...SPEICHER
SHORT TERM...ROGERS
LONG TERM...ROGERS/RIDDLE
AVIATION...SPEICHER
AREA FORECAST DISCUSSION
NWS TULSA OK
1155 PM CDT MON JUL 29 2013
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
FOR THE 6Z TAFS... A LARGE AREA OF RAIN SHOWERS WITH EMBEDDED
THUNDERSTORMS IS CURRENTLY OVERSPREADING THE REGION FROM THE NORTHWEST.
THIS ACTIVITY WILL INTERMITTENTLY AFFECT ALL TAF SITES OVERNIGHT
AND INTO THE DAY TUESDAY. TEMPORARY MVFR CONDITIONS WILL OCCUR
WITH ANY CONVECTIVE ACTIVITY... ALONG WITH ERRATIC GUSTY WINDS AND
BRIEF HEAVY RAINFALL.
&&
.PREV DISCUSSION... /ISSUED 800 PM CDT MON JUL 29 2013/
DISCUSSION...
STORMS THAT DEVELOPED NEAR THE BORDER OVER SOUTHWEST KS AND
NORTHWEST OK ARE MOVING SOUTHEAST THIS EVENING INTO NORTHWEST AND
NORTH CENTRAL OK. SEVERAL RUNS OF THE HRRR MODEL HAVE BEEN
FORECASTING THE CONVECTION TO BUILD SOUTH INTO OKLAHOMA.
CONSOLIDATING COLD POOLS WILL PUSH INTO THE STRENGTHENING
SOUTHWESTERLY LLJ THIS EVENING...AND SHOULD HELP TO KEEP THE
STORMS GOING FOR SEVERAL MORE HOURS. DAMAGING WINDS 60-70 MPH AND
MARGINALLY SEVERE HAIL WILL BE THE MAIN THREATS...AND THIS THREAT
WILL BE GREATEST BEFORE MIDNIGHT AND TO THE WEST OF TULSA. THE
CURRENT FORECAST HAS HIGH POPS NEAR THE KS BORDER AND SEE NO
REASON TO CHANGE AT THIS POINT GIVEN LATEST HRRR DATA.
LACY
PREV DISCUSSION... /ISSUED 605 PM CDT MON JUL 29 2013/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
FOR THE 0Z TAFS... SCATTERED THUNDERSTORMS MAY AFFECT NORTHEAST
OKLAHOMA AND NORTHWEST ARKANSAS SITES THIS EVENING. LATER IN THE
EVENING AND OVERNIGHT PRESENTS THE GREATEST CHANCE FOR WIDESPREAD
CONVECTIVE ACTIVITY AT THESE SITES. ANY SITE EXPERIENCING A STORM
CELL WILL LIKELY SEE TEMPORARY MVFR CONDITIONS WITH STRONG GUSTY
WINDS AND HEAVY RAINFALL.
PREV DISCUSSION... /ISSUED 407 PM CDT MON JUL 29 2013/
DISCUSSION...
PRECIPITABLE WATER VALUES IN EXCESS OF TWO BUCKS
COUPLED WITH IMPENDING THUNDER WILL DEPOSIT LOTS
OF RAIN TONIGHT... ESPECIALLY FROM ABOUT HIGHWAY
412 NORTH. THUNDER THROUGH THE EVENING HOURS MAY
BE SEVERE WITH BIG HAIL & WIND. HIGH RES MODELS
BULLISH ON QPF AND PUSHING MCS CLUSTER SOUTHEAST
WHILE LOW RES MODELS LESS SO. LOCAL 3 INCH RAIN
NOT OUT OF THE QUESTION TONIGHT..ESPECIALLY NEAR
THE KANSAS BORDER. FLOOD WATCH AREA MAY NEED TO
BE STRETCHED SOUTHEAST... IF SHORT RANGE MODELS
VERIFY. CARRIED HIGHER POPS INTO TUESDAY MORNING
GIVEN MODEL BIAS OF LESS RAIN BEHIND MCS ACTION.
ALSO LOWERED MAX TEMPS TUESDAY NORTH. LESSER POP
TUESDAY AFTERNOON AND NIGHT WITH COOL FRONT.
DRY WEDNESDAY/THURSDAY EAST OF H5 RIDGE ANCHORED
SOUTHWEST. NEXT WAVE IN NORTHWEST FLOW OVER THE
RIDGE BRINGS RAIN CHANCES AGAIN FRIDAY/SATURDAY.
GW
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...FLASH FLOOD WATCH UNTIL 1 PM TUESDAY FOR OKZ054-OKZ055-OKZ056-
OKZ057-OKZ059.
AR...NONE.
&&
$$
AVIATION...06
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
509 AM EDT TUE JUL 30 2013
.SYNOPSIS...
HIGH PRESSURE AND SLIGHTLY DRIER AIR WILL REMAIN ACROSS THE REGION TODAY.
WEDNESDAY AND THURSDAY WILL SEE AN UPPER LEVEL DISTURBANCE MOVE
THROUGH FOLLOWED BY A COLD FRONT...WHICH TOGETHER WILL BRING
NUMEROUS SHOWERS AND THUNDERSTORMS. DRY HIGH PRESSURE BUILDS BACK IN
ON FRIDAY AND WILL LINGER INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
430 AM UPDATE...CONTINUING TO EVALUATE DENSE FOG SITUATION IN OUR
LOWER SC PIEDMONT ZONES. SEVERAL OBS SITES NEAR THE SE BORDER OF THE
CWFA HAVE DIPPED TO 1/4SM OR LOWER. RUC HAS PICKED UP ON THE FOG AND
ITS SOUNDINGS INDICATE A CLASSIC FOG PROFILE WITH INCREASING
MOISTURE CONTENT WITH ALTITUDE. THE RUC DOES SUGGEST SOME DRYING IN
THE LLVLS...POSSIBLY DUE TO SETTLING OF DROPLETS. CIRRUS MOVING
OVERHEAD MAY ACCELERATE THAT. HOWEVER...IF OBS DO NOT SHOW SOME
IMPROVEMENT OVER NEXT 30-60 MIN...A DENSE FOG ADVY SEEMS LIKE A GOOD
IDEA AS TRAFFIC PICKS UP FOR THE MORNING RUSH.
TODAY...HIGH PRESSURE CENTERED OVER THE UPPER OHIO VALLEY WILL HOLD
STRONG MAINTAINING LIGHT EASTERLY WINDS ACROSS THE REGION AND
SOMEWHAT SETTLED WEATHER...WITH MOISTURE INSUFFICIENT TO EXPECT MUCH
PRECIP FROM UPSLOPING. LOW LEVEL RIDGING WILL PRODUCE POOR MIDLEVEL
LAPSE RATES AND THUS LIMIT INSTABILITY...ESPECIALLY IN THE NORTHERN
PORTION OF THE CWFA AWAY FROM THE BLUE RIDGE. HOWEVER BOTH NAM/GFS
HAVE A SMALL VORT MAX MOVING THRU...AND THE NAM KICKS OFF SOME
SHOWERS WITH IT. THOUGH INSTABILITY REMAINS WELL BELOW CLIMO...0-6KM
BULK SHEAR HIGH ENOUGH TO SUPPORT SOME SEVERE WX IF A GOOD UPDRAFT
GOES UP. NONETHELESS GIVEN THE LACK OF GOOD MOISTURE MOSTLY SCHC POPS
SOUND GOOD. HIGHS WILL RECOVER SLIGHTLY FROM YESTERDAY BUT REMAIN 3-5
DEGREES BELOW NORMAL.
TONIGHT...SYNOPTIC SCALE SHORTWAVE AND WEAK SFC LOW CROSS THE TENN
VALLEY WITH THE SHORTWAVE IN PLACE TO PROVIDE INCREASING FORCING AS
THE NIGHT GOES ON. STATIONARY FRONT TO OUR SOUTH WILL PUSH BACK NORTH
WITH MODEST ISENTROPIC LIFT IN ADDITION TO THE DYNAMIC LIFT FROM THE
SHORTWAVE. WITH THE BEST FORCING ARRIVING LATER...POPS DO LOOK TO BE
ABLE TO DROP OFF IN THE EVENING BRIEFLY BEFORE RAMPING UP THRU DAWN.
ENOUGH ELEVATED INSTABILITY IS PRESENT TO EXPECT A FEW
THUNDERSTORMS...WITH EFFECTIVE BULK SHEAR OF 20-30 KT STILL
INDICATIVE OF AT LEAST AN OUTSIDE CHANCE OF SEVERE. PWAT VALUES AGAIN
RISE ABOVE NORMAL BUT FOR THE MOST PART STAY BELOW 2 INCHES. THE LLJ
ASSOCIATED WITH THE SYSTEM IS SHOWN TO STAY TO OUR WEST...WHICH DOES
MITIGATE THE HEAVY RAIN THREAT THOUGH. ON THE OTHER HAND WINDS
REMAIN PRETTY LIGHT BELOW THE UPPER LEVELS SO STORM MOTION MAY BE
SLOW ENOUGH TO ALLOW SOME SIGNIFICANT ACCUMULATIONS. LOW TEMPS WILL
BE NEAR NORMAL.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 235 AM TUE...AN ACTIVE PATTERN WILL DEVELOP ON WED AS A SERIES
OF ULVL DISTURBANCES TRAVERSE THE BROAD SCALE TROF AXIS OVER THE ERN
CONUS. THE ECMWF IS A BIT OF AN OUTLIER WITH KEEPING THE BEST
FORCING OFF TO THE NW...WHILE THE GFS AND THE NAM BOTH BRING A GOOD
AMOUNT OF ULVL FORCING DIRECTLY OVER THE FA. PWAT VALUES WILL BE
HIGH ON WED...ABOUT 1.75 IN...BUT THERE IS NO GOOD EVIDENCE OF A
LLVL FOCUSING MECHANISM FOR CELLS TO GET HUNG UP ON AND CREATING A
SIGNFT QPF THREAT. THUS WILL COUNT ON THE OPEN UPPER WAVE TO
TRAVERSE THE AREA DURING THE DAY AND PRODUCE LESS THAN AN INCH OF
RAINFALL AT ANY GIVEN LOCATION.
SOUNDINGS LOOK RATHER INTERESTING ON THU WITH MLVL DRY AIR WORKING
IN AND STEEP LLVL LAPSE RATES SETTING UP. WITH A WEAK YET CONVERGENT
SFC FRONT PUSHING IN...THE ATMOS WILL BE SET FOR SCT TO NUMEROUS
STRONG TO SEVERE STORMS DEVELOPING IN THE AFTERNOON. THE FRONT WILL
PUSH INTO THE NC MTNS BEFORE NOON AND LOW END INSTABILITY SHOULD
KEEP DEEP CONVECTION IN CHECK...LEAVING THE FHILLS AND PIEDMONT WITH
THE BEST CHANCES FOR SEVERE ACTIVITY. SOME COLD POOL ORGANIZATION IS
POSSIBLE WITH 0-3 KM SHEAR INCREASING THROUGHOUT THE DAY. CONVECTIVE
ACTIVITY SHOULD LINGER INTO THE LATE EVENING THU AS THE FRONT SLOWS.
BUT BY 06Z FRI...A LOWER THETA/E AIRMASS AND NW/LY FLOW WILL REACH
THE FAR ERN ZONES. MAX TEMPS WILL BE A FEW DEGREES BELOW NORMAL WITH
ALL THE CLOUD COVER AND PRECIP...WHILE HIGH LLVL RH WILL KEEP MINS A
FEW DEGREES ABOVE NORMAL.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 250 AM TUE...NOT MUCH CHANGE WAS NEEDED TO THE GOING FCST. FRI
AND THE WEEKEND STILL LOOKS MOSTLY QUIET AS RELATIVELY TIGHT H5
GRADIENT AND AN OVERALL SUBS ZONE TRAVERSES THE AREA. FRI LOOKS THE
DRIEST WITH ISOL POPS MAINTAINED SAT AND SUN ACROSS THE HIGHER
TERRAIN. THE UPPER PATTERN BECOMES MORE DIFFLUENT LATE SUN AND POPS
WERE BUMPED UP A BIT TO ACCOUNT FOR POCKETS OF S/W ENERGY
INTERACTING WITH MECH LIFT MON. WITH A DRIER COLUMN AND DEEP
SUBS...SFC TEMPS SHOULD REBOUND TO AROUND NORMAL FRI AND PERSIST
THROUGH THE WEEKEND. A LITTLE COOLER ON MON DUE TO INCREASED CLOUD
COVER.
&&
.AVIATION /09Z TUESDAY THROUGH SATURDAY/...
AT KCLT /09Z UPDATE/...LOW STRATUS HAVE MOVED IN AND BROUGHT CIGS AS
LOW AS 005. DENSE FOG WILL CONTINUE IN AREAS JUST SOUTH OF THE FIELD
BUT THIS DOES NOT APPEAR TO BE EXPANDING...WITH WEAK FLOW AT THE
SFC. HEAT ISLAND EXPECTED TO KEEP DRIER CONDITIONS AT THE FIELD AND
VFR VSBY. MODELS REFLECTING THE CIG INDICATE LOW CLOUDS WILL HANG
AROUND THRU DAWN. CIRRUS ABOVE THE LAYER MAY ALLOW IT TO REMAIN SCT
THOUGH IT MAY BRIEFLY GO OVC. ONCE THE LOW DECK BURNS OFF...CU WILL
DEVELOP AND FORM A CIG BY AFTERNOON...PERHAPS BRIEFLY FORMING FIRST
AT MVFR BEFORE MIXING TO VFR. CIGS AFTER SUNSET MAINLY WILL COME
FROM MID-HIGH CLOUDS ASSOCIATED WITH INCOMING SHORTWAVE TROUGH.
PRECIP CHANCES REMAIN TOO LOW TO MENTION THRU 06Z. LIGHT NELY WINDS
WILL VEER TO SE TUE EVENING AHEAD OF THE TROUGH.
ELSEWHERE...PATCHY MVFR FOG WILL AFFECT SOME OF THE TAF SITES MAINLY
AROUND DAYBREAK TUE THOUGH GUIDANCE AND OBS SUGGEST SOME POSSIBILITY
PRIOR TO THEN...WITH DENSE FOG REMAINING ACRS THE LOWER SC PIEDMONT.
SOME SCT-BKN MVFR CLOUDS WILL LINGER OVER THE NC FOOTHILLS AND
PIEDMONT THRU DAWN. VFR CUMULUS WILL DEVELOP TODAY ALONG WITH
ISOLATED SHOWERS...THOUGH SHRA/TSRA CHANCES TOO SMALL TO MENTION.
CIGS WILL GRADUALLY LOWER AND PRECIP CHANCES INCREASE WEST TO EAST
AFTER SUNSET WITH INCOMING SHORTWAVE TROUGH...BUT PRIOR TO 06Z ONLY
A PROB30 OR VC MENTION IS WARRANTED.
OUTLOOK...A RETURN TO AN ACTIVE/WET PATTERN IS EXPECTED BY MID-WEEK.
ANOTHER PERIOD OF DRYING IS POSSIBLE BY NEXT WEEKEND.
CONFIDENCE TABLE...
09-15Z 15-21Z 21-03Z 03-09Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 97% MED 78% HIGH 85%
KAVL HIGH 100% HIGH 100% HIGH 100% MED 79%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 99% MED 78% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
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
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...SBK
NEAR TERM...WIMBERLEY
SHORT TERM...SBK
LONG TERM...SBK
AVIATION...WIMBERLEY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
442 AM EDT TUE JUL 30 2013
.SYNOPSIS...
HIGH PRESSURE AND SLIGHTLY DRIER AIR WILL REMAIN ACROSS THE REGION TODAY.
WEDNESDAY AND THURSDAY WILL SEE AN UPPER LEVEL DISTURBANCE MOVE
THROUGH FOLLOWED BY A COLD FRONT...WHICH TOGETHER WILL BRING
NUMEROUS SHOWERS AND THUNDERSTORMS. DRY HIGH PRESSURE BUILDS BACK IN
ON FRIDAY AND WILL LINGER INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
430 AM UPDATE...CONTINUING TO EVALUATE DENSE FOG SITUATION IN OUR
LOWER SC PIEDMONT ZONES. SEVERAL OBS SITES NEAR THE SE BORDER OF THE
CWFA HAVE DIPPED TO 1/4SM OR LOWER. RUC HAS PICKED UP ON THE FOG AND
ITS SOUNDINGS INDICATE A CLASSIC FOG PROFILE WITH INCREASING
MOISTURE CONTENT WITH ALTITUDE. THE RUC DOES SUGGEST SOME DRYING IN
THE LLVLS...POSSIBLY DUE TO SETTLING OF DROPLETS. CIRRUS MOVING
OVERHEAD MAY ACCELERATE THAT. HOWEVER...IF OBS DO NOT SHOW SOME
IMPROVEMENT OVER NEXT 30-60 MIN...A DENSE FOG ADVY SEEMS LIKE A GOOD
IDEA AS TRAFFIC PICKS UP FOR THE MORNING RUSH.
TODAY...HIGH PRESSURE CENTERED OVER THE UPPER OHIO VALLEY WILL HOLD
STRONG MAINTAINING LIGHT EASTERLY WINDS ACROSS THE REGION AND
SOMEWHAT SETTLED WEATHER...WITH MOISTURE INSUFFICIENT TO EXPECT MUCH
PRECIP FROM UPSLOPING. LOW LEVEL RIDGING WILL PRODUCE POOR MIDLEVEL
LAPSE RATES AND THUS LIMIT INSTABILITY...ESPECIALLY IN THE NORTHERN
PORTION OF THE CWFA AWAY FROM THE BLUE RIDGE. HOWEVER BOTH NAM/GFS
HAVE A SMALL VORT MAX MOVING THRU...AND THE NAM KICKS OFF SOME
SHOWERS WITH IT. THOUGH INSTABILITY REMAINS WELL BELOW CLIMO...0-6KM
BULK SHEAR HIGH ENOUGH TO SUPPORT SOME SEVERE WX IF A GOOD UPDRAFT
GOES UP. NONETHELESS GIVEN THE LACK OF GOOD MOISTURE MOSTLY SCHC POPS
SOUND GOOD. HIGHS WILL RECOVER SLIGHTLY FROM YESTERDAY BUT REMAIN 3-5
DEGREES BELOW NORMAL.
TONIGHT...SYNOPTIC SCALE SHORTWAVE AND WEAK SFC LOW CROSS THE TENN
VALLEY WITH THE SHORTWAVE IN PLACE TO PROVIDE INCREASING FORCING AS
THE NIGHT GOES ON. STATIONARY FRONT TO OUR SOUTH WILL PUSH BACK NORTH
WITH MODEST ISENTROPIC LIFT IN ADDITION TO THE DYNAMIC LIFT FROM THE
SHORTWAVE. WITH THE BEST FORCING ARRIVING LATER...POPS DO LOOK TO BE
ABLE TO DROP OFF IN THE EVENING BRIEFLY BEFORE RAMPING UP THRU DAWN.
ENOUGH ELEVATED INSTABILITY IS PRESENT TO EXPECT A FEW
THUNDERSTORMS...WITH EFFECTIVE BULK SHEAR OF 20-30 KT STILL
INDICATIVE OF AT LEAST AN OUTSIDE CHANCE OF SEVERE. PWAT VALUES AGAIN
RISE ABOVE NORMAL BUT FOR THE MOST PART STAY BELOW 2 INCHES. THE LLJ
ASSOCIATED WITH THE SYSTEM IS SHOWN TO STAY TO OUR WEST...WHICH DOES
MITIGATE THE HEAVY RAIN THREAT THOUGH. ON THE OTHER HAND WINDS
REMAIN PRETTY LIGHT BELOW THE UPPER LEVELS SO STORM MOTION MAY BE
SLOW ENOUGH TO ALLOW SOME SIGNIFICANT ACCUMULATIONS. LOW TEMPS WILL
BE NEAR NORMAL.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 235 AM TUE...AN ACTIVE PATTERN WILL DEVELOP ON WED AS A SERIES
OF ULVL DISTURBANCES TRAVERSE THE BROAD SCALE TROF AXIS OVER THE ERN
CONUS. THE ECMWF IS A BIT OF AN OUTLIER WITH KEEPING THE BEST
FORCING OFF TO THE NW...WHILE THE GFS AND THE NAM BOTH BRING A GOOD
AMOUNT OF ULVL FORCING DIRECTLY OVER THE FA. PWAT VALUES WILL BE
HIGH ON WED...ABOUT 1.75 IN...BUT THERE IS NO GOOD EVIDENCE OF A
LLVL FOCUSING MECHANISM FOR CELLS TO GET HUNG UP ON AND CREATING A
SIGNFT QPF THREAT. THUS WILL COUNT ON THE OPEN UPPER WAVE TO
TRAVERSE THE AREA DURING THE DAY AND PRODUCE LESS THAN AN INCH OF
RAINFALL AT ANY GIVEN LOCATION.
SOUNDINGS LOOK RATHER INTERESTING ON THU WITH MLVL DRY AIR WORKING
IN AND STEEP LLVL LAPSE RATES SETTING UP. WITH A WEAK YET CONVERGENT
SFC FRONT PUSHING IN...THE ATMOS WILL BE SET FOR SCT TO NUMEROUS
STRONG TO SEVERE STORMS DEVELOPING IN THE AFTERNOON. THE FRONT WILL
PUSH INTO THE NC MTNS BEFORE NOON AND LOW END INSTABILITY SHOULD
KEEP DEEP CONVECTION IN CHECK...LEAVING THE FHILLS AND PIEDMONT WITH
THE BEST CHANCES FOR SEVERE ACTIVITY. SOME COLD POOL ORGANIZATION IS
POSSIBLE WITH 0-3 KM SHEAR INCREASING THROUGHOUT THE DAY. CONVECTIVE
ACTIVITY SHOULD LINGER INTO THE LATE EVENING THU AS THE FRONT SLOWS.
BUT BY 06Z FRI...A LOWER THETA/E AIRMASS AND NW/LY FLOW WILL REACH
THE FAR ERN ZONES. MAX TEMPS WILL BE A FEW DEGREES BELOW NORMAL WITH
ALL THE CLOUD COVER AND PRECIP...WHILE HIGH LLVL RH WILL KEEP MINS A
FEW DEGREES ABOVE NORMAL.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 250 AM TUE...NOT MUCH CHANGE WAS NEEDED TO THE GOING FCST. FRI
AND THE WEEKEND STILL LOOKS MOSTLY QUIET AS RELATIVELY TIGHT H5
GRADIENT AND AN OVERALL SUBS ZONE TRAVERSES THE AREA. FRI LOOKS THE
DRIEST WITH ISOL POPS MAINTAINED SAT AND SUN ACROSS THE HIGHER
TERRAIN. THE UPPER PATTERN BECOMES MORE DIFFLUENT LATE SUN AND POPS
WERE BUMPED UP A BIT TO ACCOUNT FOR POCKETS OF S/W ENERGY
INTERACTING WITH MECH LIFT MON. WITH A DRIER COLUMN AND DEEP
SUBS...SFC TEMPS SHOULD REBOUND TO AROUND NORMAL FRI AND PERSIST
THROUGH THE WEEKEND. A LITTLE COOLER ON MON DUE TO INCREASED CLOUD
COVER.
&&
.AVIATION /09Z TUESDAY THROUGH SATURDAY/...
AT KCLT /09Z UPDATE/...LOW STRATUS HAVE MOVED IN AND BROUGHT CIGS AS
LOW AS 005. DENSE FOG WILL CONTINUE IN AREAS JUST SOUTH OF THE FIELD
BUT THIS DOES NOT APPEAR TO BE EXPANDING...WITH WEAK FLOW AT THE
SFC. HEAT ISLAND EXPECTED TO KEEP DRIER CONDITIONS AT THE FIELD AND
VFR VSBY. MODELS REFLECTING THE CIG INDICATE IT WILL HANG AROUND
THRU DAWN...THOUGH WITH CIRRUS MOVING OVER THE LAYER IT MAY BREAK UP
A BIT...HENCE TEMPO SCATTERING. ONCE THE LOW DECK BURNS OFF...CU
WILL DEVELOP AND FORM A CIG BY AFTERNOON...PERHAPS BRIEFLY FORMING
FIRST AT MVFR BEFORE MIXING TO VFR. CIGS AFTER SUNSET MAINLY WILL
COME FROM MID-HIGH CLOUDS ASSOCIATED WITH INCOMING SHORTWAVE TROUGH.
PRECIP CHANCES REMAIN TOO LOW TO MENTION THRU 06Z. LIGHT NELY WINDS
WILL VEER TO SE TUE EVENING AHEAD OF THE TROUGH.
ELSEWHERE...PATCHY MVFR FOG WILL AFFECT SOME OF THE TAF SITES MAINLY
AROUND DAYBREAK TUE THOUGH GUIDANCE AND OBS SUGGEST SOME POSSIBILITY
PRIOR TO THEN...WITH DENSE FOG REMAINING ACRS THE LOWER SC PIEDMONT.
SOME SCT-BKN MVFR CLOUDS WILL LINGER OVER THE NC FOOTHILLS AND
PIEDMONT THRU DAWN. VFR CUMULUS WILL DEVELOP TODAY ALONG WITH
ISOLATED SHOWERS...THOUGH SHRA/TSRA CHANCES TOO SMALL TO MENTION.
CIGS WILL GRADUALLY LOWER AND PRECIP CHANCES INCREASE WEST TO EAST
AFTER SUNSET WITH INCOMING SHORTWAVE TROUGH...BUT PRIOR TO 06Z ONLY
A PROB30 OR VC MENTION IS WARRANTED.
OUTLOOK...A RETURN TO AN ACTIVE/WET PATTERN IS EXPECTED BY MID-WEEK.
ANOTHER PERIOD OF DRYING IS POSSIBLE BY NEXT WEEKEND.
CONFIDENCE TABLE...
08-14Z 14-20Z 20-02Z 02-08Z
KCLT HIGH 94% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 94% HIGH 98% HIGH 85% MED 79%
KAVL HIGH 89% HIGH 100% HIGH 100% HIGH 83%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 98% HIGH 85% HIGH 93%
KAND HIGH 89% HIGH 100% HIGH 100% HIGH 100%
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
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...SBK
NEAR TERM...WIMBERLEY
SHORT TERM...SBK
LONG TERM...SBK
AVIATION...WIMBERLEY
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
947 AM CDT TUE JUL 30 2013
.DISCUSSION...
931 AM CDT
UPDATED MORNING POP/WEATHER GRIDS TO ACCOUNT FOR CURRENT RADAR
TRENDS AND ALSO BOOSTED POPS THIS AFTERNOON...MAINLY FOR SOUTH AND
SOUTHWEST PORTIONS OF THE AREA. FORECAST SOUNDINGS FROM ORD ARE
STILL SHOWING CONSIDERABLE DRY AIR AROUND 800MB FOR THE METRO
AREA...BUT OBVIOUSLY THE AIR IS FAIRLY WELL SATURATED FARTHER TO
THE SOUTHWEST. THE CURRENT TRENDS ARE DEPICTED NICELY BY MOISTURE
CONVERGENCE FIELDS IN THE RAP MODEL...SO HAVE LEANED TOWARD THAT
EVOLUTION FOR THE REST OF THE DAY. MAY NEED FURTHER UPDATES IF
ACTIVITY SHOWS GOOD SIGNS OF HOLDING TOGETHER LATER INTO THE
AFTERNOON. GIVEN EXISTING AND FORECAST CAPE TRENDS AND SOUNDING
PROFILES...MAY ALSO NEED TO ADD MENTION OF THUNDERSTORMS LATER
TODAY...BUT MIDLEVEL LAPSE RATES ARE ONLY MARGINALLY FAVORABLE.
LENNING
&&
.PREV DISCUSSION...
323 AM CDT
TODAY...
SFC RIDGING CONTINUES TO BE AN INFLUENCE ON THE REGION...DESPITE
DRIFTING EAST OF THE CWFA AND BECOMING CENTERED OVER THE EASTERN
OHIO VALLEY THIS MORNING. IR IMAGERY DEPICTS A COMPLEX OF
THUNDERSTORMS ACROSS THE SOUTHERN PLAINS...WITH REGIONAL RADAR
SHOWING PRECIP RETURNS LIFTING INTO NORTHEAST MISSOURI/SOUTHEAST
IOWA. FOR MUCH OF THE DAY TODAY EXPECT SFC RIDGING TO CONTINUE TO
KEEP PRECIP WEST/SOUTHWEST OF THE CWFA. GUIDANCE HOLDS ONTO THE
SOUTHEAST FLOW AT THE SFC...WITH SOUNDINGS SUGGESTING CONSIDERABLE
DRY AIR THRU 15Z THEN SLOWLY MOISTENING FROM THE TOP DOWN. PWAT
VALUES SLOWLY INCREASE...HOVERING ARND 1.8" BY LATE THIS AFTN/EVE.
BY 18Z EXPECT SCATTERED PRECIP TO BEGIN PUSHING OVER THE CWFA. BASED
ON THE SOUNDINGS CONVECTIVE POTENTIAL REMAINS VERY LOW...EXCEPT FOR
FAR SOUTHERN AREAS OF THE CWFA. OTHERWISE EXPECT PRECIP TO REMAIN
LIGHT IN INTENSITY AND MINIMAL COVERAGE.
WITH GRADUAL THICKENING OF THE CLOUD SHIELD...TEMPS WILL INITIALLY
WARM THEN THE RATE OF CLIMB WILL BEGIN TO SLOW GIVEN THE INCREASED
MOISTURE IN THE ATMOSPHERE. STILL THINK THAT TEMPS WILL WARM TO THE
MID 70S...HOWEVER IF CLOUDS CAN THICKEN FASTER THIS MORNING TEMPS
MAY STRUGGLE TO WARM BEYOND THE LOW 70S.
CONFIDENCE...MEDIUM.
TONIGHT THROUGH WEDNESDAY...
WEAK SHORTWAVE CONTINUES TO LIFT NORTHEAST ACROSS MISSOURI LATE THIS
AFTN/EARLY EVE...WHILE ANTI-CYCLONIC FLOW OVER THE OHIO VALLEY
CONTINUES TO PROVIDE A DRY INFLUENCE ON THE NEAR SFC ENVIRONMENT
ACROSS NORTHERN IL/NORTHWEST IN. SFC WINDS APPEAR TO HOLD FROM THE
SOUTHEAST...AND UNDER A LIGHT GRADIENT WILL LIKELY BE LESS THAN 10
MPH. THIS COULD BE JUST ENOUGH OF A DRY FLOW IN THE LLVLS TO HOLD
FULL SATURATION OF THE PROFILE. GUIDANCE DOES INDICATE A SLOW
MOISTENING OF THE LOW/MID LVLS AFT 21Z THIS AFTN...WITH PWAT VALUES
STEADILY INCREASING TO ARND 1.5-1.8". THE TREND HAS BEEN DRIER AND
FURTHER SOUTH WITH THIS SYSTEM...HOWEVER JUST ENOUGH MOISTURE COULD
LIFT OVERHEAD AND WITH SOME OMEGA OR LIFT PRESENT...SPRINKLES/LIGHT
SHRA COULD DEVELOP LATE THIS EVENING/OVERNIGHT. LOCAL HI-RES WRF
SOLUTION KEEPS ALL PRECIP TO THE SOUTH OF A PONTIAC TO FOWLER LINE.
HAVE TRIMMED BACK ON POPS TO THE HIGH TEENS...AND EXPECT COVERAGE TO
BE MINIMAL WITH PRECIP TONIGHT. IN ADDITION DROPLET SIZE WILL BE
SMALL AS WELL...WHICH COULD TRANSLATE INTO DRIZZLE OR CHANGING
PRECIP TO SPRINKLES INSTEAD OF SHOWERS.
WITH A 500MB WAVE RATHER FLAT...THIS SYSTEM WILL REMAIN PROGRESSIVE
AND PUSH TO THE EAST BY WED MORNING. ALONG THE BACK EDGE OF THE
DEPARTING WEAK SFC WAVE IT APPEARS SOME DIFLUENT FLOW TRIES TO
DEVELOP AND COULD BRING A BRIEF END TO THE PRECIP BY DAYBREAK WED.
THEN THE FOCUS TURNS TOWARDS AN ADVANCING FRONTAL BOUNDARY THAT WILL
BE SLIDING INTO THE UPPER MIDWEST EARLY WED.
LLVL FLOW WILL BECOME SOUTHERLY TO SOUTHWESTERLY AHEAD OF THE COLD
FRONT...WITH MARGINAL INSTABILITY DEVELOPING IN THE AFTN HOURS WED.
WITH THE LACK OF STRONG SHEAR AND MODEL SOUNDINGS INDICATING SOME
DRY AIR IN THE NEAR SFC...IT IS CONCEIVABLE THAT MUCH OF WED COULD
BE DRY. AS PREVIOUSLY NOTED IN REGARDS TO THE LCL HI-RES WRF...THIS
SOLUTION CONTINUES THE DRY THEME FOR WED. AT THIS POINT HAVE ONLY
TRIMMED BACK ON POPS FOR WED...AND FOCUSED THE TIMING TOWARDS THE
AFTN/EVE HOURS OR CLOSER TO FROPA. 500MB TROUGH AXIS APPEARS TO PUSH
INTO THE WESTERN GREAT LAKES ARND 00Z THUR...WITH DIMINISHING LLVL
MOISTURE. MID-LVL SHEAR WILL INCREASE AS THE BNDRY NEARS...AND WITH
MARGINAL INSTABILITY COULD ALLOW SOME ISOLATED THUNDERSTORMS TO
DEVELOP LATE WED AFTN.
IN REGARDS TO TEMPS TONIGHT...EXPECT CONSIDERABLE CLOUD COVER TO
HOLD TEMPS SLIGHTLY WARMER OR IN THE MID 60S AWAY FROM LAKE MICHIGAN
AND UPR 60S CLOSER TO THE LAKE. THEN FOR WED TEMPS WILL BE SLIGHTLY
WARMER AND CLOSER TO 80 DEG. IF THE SOUTH/SOUTHWEST FLOW IS SLIGHTLY
STRONGER WED IN ADVANCE OF THE FRONT...TEMPS MAY BE ABLE TO WARM
FURTHER OR 80-83 DEG.
CONFIDENCE...MEDIUM.
CONFIDENCE IN PRECIP...LOW.
THURSDAY THROUGH FRIDAY...
500MB TROUGH QUICKLY SLIDES OVERHEAD WITH ANTI-CYCLONIC FLOW
BUILDING INTO THE REGION FROM THE WEST. THIS WILL AID IN PROVIDING
DRY WEATHER FOR THUR/THUR NIGHT. SFC RIDGE PUSHES FURTHER SOUTH
ACROSS THE TENN VALLEY FRI...WHILE A LOBE OF VORTICITY IS PROGGED TO
SLIDE SOUTHEAST ACROSS THE WESTERN GREAT LAKES FRI. THIS APPEARS TO
BE ASSOCIATED WITH A FRONTAL BOUNDARY...WHICH MAY HAVE SOME PRECIP
ACCOMPANYING FROPA FRI/FRI EVE. ALTHOUGH THE SETUP LOOKS MORE
FAVORABLE FOR A DRY FROPA AS ANTI-CYCLONIC FLOW WILL BE DEPARTING
WITH YET ANOTHER ANTI-CYCLONIC FLOW SLIDING SOUTHEAST ACROSS THE
NORTHERN PLAINS/UPPER MIDWEST FRI NIGHT.
TEMPS CONTINUE TO BE UNSEASONABLY COOL...WITH AFTN HIGHS STRUGGLING
TO WARM BEYOND THE UPR 70S IN MANY LOCATIONS. A FEW SITES MAY TOUCH
80 DEG FRI AFTN.
CONFIDENCE...MEDIUM.
SATURDAY THROUGH MONDAY...
EXTENDED PERIODS CONTINUE TO FEATURE A COOL NORTHWEST SETUP WITH
ENSEMBLES DEMONSTRATING MINIMAL NOISE OR DIFFERENCES. THE STRENGTH
OF THE DOWNSTREAM RIDGE OVER THE CANADIAN MARITIME DOES EXHIBIT SOME
WEAKENING SUN...WHICH SHOULD ALLOW THE GREAT LAKES TROUGH TO WEAKEN
AND PUSH EAST. HOWEVER PROGRESSING TOWARDS THE FINAL FEW
PERIODS...HIGH LATITUDE RIDGING IS PROGGED TO DEVELOP OVER THE NORTH
ATLANTIC AND STRETCH WEST ACROSS WESTERN CANADA. IF THIS SOLUTION
VERIFIES...FLOW ACROSS THE GREAT LAKES REGION WILL LIKELY REMAIN IN
A UNSEASONABLY COOL SETUP.
OPERATIONAL SOLUTIONS HAVE SFC RIDGING BUILDING IN FOR SAT AND
LINGERING THRU SUN NGT...WHICH WILL PROVIDE DRY WEATHER. THEN THE
500MB FLOW BEGINS TO FLATTEN AND BECOME MORE FLUID...WITH A FRONTAL
BOUNDARY AND A WEAK SYSTEM APPROACHING THE REGION TOWARDS THE FINAL
PERIODS WITH A CHANCE OF PRECIP FOR EARLY NEXT WEEK.
CONFIDENCE...MEDIUM/HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* CHANCE OF LIGHT SHOWERS LATE MORNING THROUGH AFTERNOON...
SOMEWHAT BETTER CHANCE THIS EVENING.
* POTENTIAL FOR MVFR CIGS OVERNIGHT INTO WED MORNING...SMALL
POTENTIAL FOR IFR CIGS.
TRS
//DISCUSSION...UPDATED 12Z...
AN AREA OF SHOWERS/RAIN OVER WESTERN IL CONTINUES TO SPREAD NORTH
AND NORTHEAST THIS MORNING AND IS SLOWLY ERODING ON THE NORTHERN
EDGE AS IT ENCOUNTERS DRIER AIR. SHORT TERM/HI RES GUIDANCE IS IN
FAIR AGREEMENT THAT THIS ERODING TREND WILL CONTINUE THIS MORNING.
BUT DO EXPECT THIS ACTIVITY TO REACH A RFD/DKB/ARR LINE...AT LEAST
IN THE FORM OF SPRINKLES. ADDITIONAL SHOWERS MAY DEVELOP LATER
THIS AFTERNOON AND CONTINUE INTO THIS EVENING BUT CONFIDENCE
REGARDING COVERAGE IS FAIRLY LOW AND INCLUDED VICINITY MENTION BUT
STILL EXPECT MANY DRY HOURS.
WINDS WILL REMAIN SOUTHEASTERLY INTO THIS EVENING WITH SPEEDS
INCREASING INTO THE 7-10KT RANGE. ITS POSSIBLE A MORE TRADITIONAL
LAKE BREEZE MAY DEVELOP THIS AFTERNOON...ESPECIALLY FROM CHICAGO
NORTH INTO LAKE COUNTY IL. HOW FAR INLAND IT MOVES IS UNCERTAIN
AND TRENDS WILL NEED TO BE MONITORED INTO THIS AFTERNOON. SPEEDS
WILL DIMINISH THIS EVENING WITH LIGHT AND VARIABLE OR CALM WINDS
EXPECTED TONIGHT.
THE LOW LEVELS CONTINUE TO MOISTEN THROUGH THE EVENING AND INTO
THE OVERNIGHT HOURS. THERE IS A FAIRLY EXTENSIVE AREA OF LIFR/IFR
CIGS ACROSS THE CENTRAL PLAINS AND SOME OF THIS WILL LIKELY SHIFT
EAST TONIGHT. MOST CONFIDENT OF THIS REACHING RFD BUT FOR THE REST
OF THE TAFS...HAVE JUST INCLUDED SCATTERED IFR MENTION FOR NOW. CMS
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* HIGH FOR SOME -RA/-SHRA ACROSS LOCAL AREA LATE MORNING THOUGH
EVENING.
* MODERATE THAT ANY PCPN WILL BE OPERATIONALLY INSIGNIFICANT
THOUGH LOCALIZED SPOTS MAY SEE ENOUGH TO WET THE GROUND.
* MEDIUM FOR MVFR CIGS OVERNIGHT/WEDNESDAY MORNING.
TRS
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
* WEDNESDAY NIGHT...CHANCE OF TSRA.
* THURSDAY...DRY/VFR.
* FRIDAY...CHANCE OF TSRA.
* SATURDAY AND SUNDAY...DRY/VFR.
* MONDAY...CHANCE OF TSRA.
&&
.MARINE...
305 AM...BROAD HIGH PRESSURE OVER THE LAKES REGION AND EXTENDING
INTO THE MID ATLANTIC WILL SLOWLY MOVE EAST TODAY AND TONIGHT AS
LOW PRESSURE OF NORTHERN MANITOBA MOVES EAST TO NEAR JAMES BAY BY
THURSDAY MORNING. SOUTHERLY WINDS WILL CONTINUE INTO WEDNESDAY
AFTERNOON WHEN A TRAILING COLD FRONT FROM THE LOW MOVES ACROSS THE
LAKE SHIFTING WINDS NORTHWEST. AS HIGH PRESSURE MOVES FROM THE
NORTHERN PLAINS WEDNESDAY NIGHT TO THE OHIO VALLEY THURSDAY
NIGHT...THE GRADIENT TIGHTENS SOME WEDNESDAY NIGHT INTO THURSDAY
MORNING ACROSS THE SOUTHERN HALF OR SO OF THE LAKE AND WHILE A
PERIOD OF 15-20 KTS LOOKS POSSIBLE...COULD BE SOME HIGHER GUSTS
INTO THE MID 20KT RANGE TOWARD THURSDAY MORNING. SPEEDS DIMINISH
THURSDAY NIGHT BUT WINDS REMAIN GENERALLY WESTERLY UNTIL ANOTHER
COLD FRONT MOVES ACROSS THE LAKES REGION FRIDAY AND FRIDAY NIGHT.
CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
951 AM CDT TUE JUL 30 2013
.UPDATE...
ISSUED AT 950 AM CDT TUE JUL 30 2013
UPDATED FORECAST TO DROP DENSE FOG ADVISORY AND INCREASE CLOUD
COVER THROUGH THE MORNING WITH AREAS OF PATCHY FOG CONTINUING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT TUE JUL 30 2013
TODAY AND TONIGHT...DENSE FOG WOULD APPEAR TO BE VERY SHALLOW
THIS MORNING WITH THE MOON VISIBLE AT KLBF AND NEDOR SHOWING IT
LIFTING AT KLXN. SO WE WOULD EXPECT A RAPID CLEARING AFTER SUNRISE
IN SOME AREAS AS SATELLITE SHOWS AREAS OF STRATUS AT THE SAME TIME
WHICH WOULD SLOW THE LIFTING PROCESS.
A WEAK AND DECAYING MCS ACROSS NWRN NEB/SWRN SD THIS MORNING IN
COMBINATION WITH A WEAK DISTURBANCE OVER ERN COLO COULD PERHAPS
SPREAD ISOLATED SHOWERS AND THUNDERSTORMS INTO WRN NEB.
THE HRRR THEN SHOWS CONVECTIVE DESTABILIZATION ACROSS SWRN NEB BY
20Z WHICH IS PROBABLY AN HOUR OR TWO TOO FAST. THE MAIN IMPULSE
WOULD APPEAR TO BE DROPPING SOUTHEAST THROUGH NERN WY/WRN SD AT
20Z...STILL HOURS AWAY FROM THE FCST AREA. A MCS IS EXPECTED TO
DEVELOP OUT OF THE STORMS FIRING ACROSS THE NRN HIGH PLAINS WHICH
SHOULD SWEEP THRU NRN NEB OVERNIGHT. THE MCS SHOULD REMAIN MOSTLY
ALONG AND NORTH OF HIGHWAY 20.
TEMPERATURES TODAY ARE EXPECTED TO RISE INTO THE LOW TO MID 80S
IN MOST AREAS GIVEN THE CONTINUED SOUTH AND SOUTHEAST WINDS
CIRCULATING AROUND HIGH PRESSURE CENTERED OVER THE MIDWEST. THE
ENSUING WARM AIR ADVECTION FUELING THE MCS TONIGHT SHOULD KEEP
SKIES MOSTLY CLEAR SOUTH OF THE CONVECTIVE COMPLEX. THE NAM12
HINTS AT A BANK OF STRATUS FILLING IN ACROSS NWRN NEB IN THE WAKE
OF THE MCS AROUND 12Z.
SEVERE WEATHER POTENTIAL WITH THE THUNDERSTORMS THIS AFTERNOON
AND TONIGHT IS LIMITED TO 5 PERCENT OR ISOLATED WITH THE BEST
INSTABILITY AND 40 TO 50 KT 1 TO 6 KM SHEAR ACROSS NRN NEB MOSTLY
ASSOCIATED WITH THE DEVELOPING MCS. MODEL INDICATIONS SUGGEST THE
BLACK HILLS COULD BE THE GENESIS FOR A CLUSTER OF STORMS FORMING
LATE IN THE AFTERNOON WHICH WOULD MOVE EAST SOUTHEAST TOWARD
KVTN-KANW-KONL DURING THE EVENING AND OVERNIGHT. THIS IN TURN
COULD CERTAINLY INCREASE THE SEVERE WEATHER POTENTIAL IN THOSE
AREAS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 400 AM CDT TUE JUL 30 2013
WEDNESDAY MORNING LINGER SHOWERS WILL BE POSSIBLE ACROSS PORTIONS
OF CENTRAL/NORTH CENTRAL NEB. THEN BREAKS IN THE CLOUDS SHOULD
HELP TO PUSH HIGHS INTO THE 80S. LATE IN THE DATE MODELS IN
AGREEMENT WITH A BOUNDARY STRETCHED FROM WEST CENTRAL KS
NORTHEAST INTO CENTRAL NEB AND ON TOWARDS THE WESTERN GREAT
LAKES. THUNDERSTORMS WILL BE POSSIBLE ALONG THE SLOW MOVING
BOUNDARY...HOWEVER IMPACT TO THE CWA IN QUESTIONS. THE LATEST NAM
AND GFS HAVE PUSHED THE BOUNDARY JUST SE OF THE CWA BY PEAK
HEATING...HOWEVER THE EC AND GEM DO DEVELOP ACTIVITY IN THE SE
CWA. WILL TREND DOWN WITH POPS...ALTHOUGH STILL RETAIN SLGHT CHC
IN THE FAR SE ZONES. MORE OF A FOCUS WILL BE THE NEXT SHORT WAVE
CROSSING THE ROCKIES. THIS WAVE SHOULD ALLOW DEVELOPMENT ON THE
HIGHER TERRAIN WITH FLOW TO PUSH THIS INTO THE PANHANDLE AND
WESTERN NEBRASKA OVERNIGHT.
THURSDAY WILL SEE YET ANOTHER SHORT WAVE TO PUSH ACROSS THE AREA.
MODELS CONTINUE TO SHOW GOOD INSTABILITY WITH DECENT SHEAR...ALSO
WILL SEE A SURF LOW DEVELOP NEAR NE CO. ANY ACTIVITY DEVELOPING IN
THE EVENING FROM PEAK HEATING WILL LIKELY BE SUSTAINED BY A 30 TO
40K LL JET. LOW FREEZING LEVEL WITH STEEP LAPSE RATE SHOULD RESULT
IN A FEW STRONG TO EVEN SEVERE STORMS...WITH HAIL THE MAIN THREAT.
FRIDAY WILL SEE AN UPPER LEVEL LOW COME ONSHORE TO THE PAC
NW...THIS WILL FLATTEN THE RIDGE AND PUSH IT EASTWARD. INITIALLY
THOUGHT THERE COULD BE A WARM UP...HOWEVER MODELS CONTINUE TO
BRING GOOD MOISTURE AROUND THE RIDGE...RESULTING IN MORE CLOUDS
THAN SUN. FORECAST RESULTS IN BELOW NORMAL HIGHS...WHICH IS CLOSE
TO MOS GUIDANCE.
LITTLE CHANGES THROUGH THE WEEKEND FOR THE AREA...AS RIDGE REMAINS
TO THE SOUTH AND LOW WILL TRAVERSE ACROSS THE US/CAN BORDER. FLOW
WILL CONTINUE TO BE NORTHWESTERLY TO ZONAL...AND MODELS CONTINUE
TO BRING WAVE AFTER WAVE ACROSS THE AREA. QPF MAY NOT BE
SIGNIFICANT...HOWEVER WILL NEED TO CONTINUE TO MENTION IN NEARLY
EVERY PERIOD PENDING TIMING OF THE WAVES. TEMPS WILL GENERALLY BE
BELOW NORMAL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 617 AM CDT TUE JUL 30 2013
LIFR CIGS SHOULD IMPROVE TO IFR/MVFR/VFR FROM WEST TO EAST THIS
MORNING. BOTH THE NAM AND RAP MODELS SHOW THIS AREA OF CLOUDS
EXITING BETWEEN 18Z-20Z. THEREAFTER...A TSTM COMPLEX SHOULD BEGIN
ORGANIZING ACROSS NERN WY/WRN SD WHICH SHOULD MOVE EAST AND
SOUTHEAST AFFECTING NRN NEBRASKA...MAINLY AFTER 00Z. NOTE THAT A
FEW STORMS COULD FORM ACROSS THE NEBRASKA PANHANDLE THIS AFTERNOON
AND MOVE EAST BUT THE MAIN COMPLEX FORMS ACROSS SD AND TSTMS ARE
NOT EXPECTED SOUTH OF NEBRASKA HIGHWAY 2 TONIGHT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
UPDATE...POWER
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
622 AM CDT TUE JUL 30 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT TUE JUL 30 2013
TODAY AND TONIGHT...DENSE FOG WOULD APPEAR TO BE VERY SHALLOW
THIS MORNING WITH THE MOON VISIBLE AT KLBF AND NEDOR SHOWING IT
LIFTING AT KLXN. SO WE WOULD EXPECT A RAPID CLEARING AFTER SUNRISE
IN SOME AREAS AS SATELLITE SHOWS AREAS OF STRATUS AT THE SAME TIME
WHICH WOULD SLOW THE LIFTING PROCESS.
A WEAK AND DECAYING MCS ACROSS NWRN NEB/SWRN SD THIS MORNING IN
COMBINATION WITH A WEAK DISTURBANCE OVER ERN COLO COULD PERHAPS
SPREAD ISOLATED SHOWERS AND THUNDERSTORMS INTO WRN NEB.
THE HRRR THEN SHOWS CONVECTIVE DESTABILIZATION ACROSS SWRN NEB BY
20Z WHICH IS PROBABLY AN HOUR OR TWO TOO FAST. THE MAIN IMPULSE
WOULD APPEAR TO BE DROPPING SOUTHEAST THROUGH NERN WY/WRN SD AT
20Z...STILL HOURS AWAY FROM THE FCST AREA. A MCS IS EXPECTED TO
DEVELOP OUT OF THE STORMS FIRING ACROSS THE NRN HIGH PLAINS WHICH
SHOULD SWEEP THRU NRN NEB OVERNIGHT. THE MCS SHOULD REMAIN MOSTLY
ALONG AND NORTH OF HIGHWAY 20.
TEMPERATURES TODAY ARE EXPECTED TO RISE INTO THE LOW TO MID 80S
IN MOST AREAS GIVEN THE CONTINUED SOUTH AND SOUTHEAST WINDS
CIRCULATING AROUND HIGH PRESSURE CENTERED OVER THE MIDWEST. THE
ENSUING WARM AIR ADVECTION FUELING THE MCS TONIGHT SHOULD KEEP
SKIES MOSTLY CLEAR SOUTH OF THE CONVECTIVE COMPLEX. THE NAM12
HINTS AT A BANK OF STRATUS FILLING IN ACROSS NWRN NEB IN THE WAKE
OF THE MCS AROUND 12Z.
SEVERE WEATHER POTENTIAL WITH THE THUNDERSTORMS THIS AFTERNOON
AND TONIGHT IS LIMITED TO 5 PERCENT OR ISOLATED WITH THE BEST
INSTABILITY AND 40 TO 50 KT 1 TO 6 KM SHEAR ACROSS NRN NEB MOSTLY
ASSOCIATED WITH THE DEVELOPING MCS. MODEL INDICATIONS SUGGEST THE
BLACK HILLS COULD BE THE GENESIS FOR A CLUSTER OF STORMS FORMING
LATE IN THE AFTERNOON WHICH WOULD MOVE EAST SOUTHEAST TOWARD
KVTN-KANW-KONL DURING THE EVENING AND OVERNIGHT. THIS IN TURN
COULD CERTAINLY INCREASE THE SEVERE WEATHER POTENTIAL IN THOSE
AREAS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 400 AM CDT TUE JUL 30 2013
WEDNESDAY MORNING LINGER SHOWERS WILL BE POSSIBLE ACROSS PORTIONS
OF CENTRAL/NORTH CENTRAL NEB. THEN BREAKS IN THE CLOUDS SHOULD
HELP TO PUSH HIGHS INTO THE 80S. LATE IN THE DATE MODELS IN
AGREEMENT WITH A BOUNDARY STRETCHED FROM WEST CENTRAL KS
NORTHEAST INTO CENTRAL NEB AND ON TOWARDS THE WESTERN GREAT
LAKES. THUNDERSTORMS WILL BE POSSIBLE ALONG THE SLOW MOVING
BOUNDARY...HOWEVER IMPACT TO THE CWA IN QUESTIONS. THE LATEST NAM
AND GFS HAVE PUSHED THE BOUNDARY JUST SE OF THE CWA BY PEAK
HEATING...HOWEVER THE EC AND GEM DO DEVELOP ACTIVITY IN THE SE
CWA. WILL TREND DOWN WITH POPS...ALTHOUGH STILL RETAIN SLGHT CHC
IN THE FAR SE ZONES. MORE OF A FOCUS WILL BE THE NEXT SHORT WAVE
CROSSING THE ROCKIES. THIS WAVE SHOULD ALLOW DEVELOPMENT ON THE
HIGHER TERRAIN WITH FLOW TO PUSH THIS INTO THE PANHANDLE AND
WESTERN NEBRASKA OVERNIGHT.
THURSDAY WILL SEE YET ANOTHER SHORT WAVE TO PUSH ACROSS THE AREA.
MODELS CONTINUE TO SHOW GOOD INSTABILITY WITH DECENT SHEAR...ALSO
WILL SEE A SURF LOW DEVELOP NEAR NE CO. ANY ACTIVITY DEVELOPING IN
THE EVENING FROM PEAK HEATING WILL LIKELY BE SUSTAINED BY A 30 TO
40K LL JET. LOW FREEZING LEVEL WITH STEEP LAPSE RATE SHOULD RESULT
IN A FEW STRONG TO EVEN SEVERE STORMS...WITH HAIL THE MAIN THREAT.
FRIDAY WILL SEE AN UPPER LEVEL LOW COME ONSHORE TO THE PAC
NW...THIS WILL FLATTEN THE RIDGE AND PUSH IT EASTWARD. INITIALLY
THOUGHT THERE COULD BE A WARM UP...HOWEVER MODELS CONTINUE TO
BRING GOOD MOISTURE AROUND THE RIDGE...RESULTING IN MORE CLOUDS
THAN SUN. FORECAST RESULTS IN BELOW NORMAL HIGHS...WHICH IS CLOSE
TO MOS GUIDANCE.
LITTLE CHANGES THROUGH THE WEEKEND FOR THE AREA...AS RIDGE REMAINS
TO THE SOUTH AND LOW WILL TRAVERSE ACROSS THE US/CAN BORDER. FLOW
WILL CONTINUE TO BE NORTHWESTERLY TO ZONAL...AND MODELS CONTINUE
TO BRING WAVE AFTER WAVE ACROSS THE AREA. QPF MAY NOT BE
SIGNIFICANT...HOWEVER WILL NEED TO CONTINUE TO MENTION IN NEARLY
EVERY PERIOD PENDING TIMING OF THE WAVES. TEMPS WILL GENERALLY BE
BELOW NORMAL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 617 AM CDT TUE JUL 30 2013
LIFR CIGS SHOULD IMPROVE TO IFR/MVFR/VFR FROM WEST TO EAST THIS
MORNING. BOTH THE NAM AND RAP MODELS SHOW THIS AREA OF CLOUDS
EXITING BETWEEN 18Z-20Z. THEREAFTER...A TSTM COMPLEX SHOULD BEGIN
ORGANIZING ACROSS NERN WY/WRN SD WHICH SHOULD MOVE EAST AND
SOUTHEAST AFFECTING NRN NEBRASKA...MAINLY AFTER 00Z. NOTE THAT A
FEW STORMS COULD FORM ACROSS THE NEBRASKA PANHANDLE THIS AFTERNOON
AND MOVE EAST BUT THE MAIN COMPLEX FORMS ACROSS SD AND TSTMS ARE
NOT EXPECTED SOUTH OF NEBRASKA HIGHWAY 2 TONIGHT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM CDT /9 AM MDT/ THIS MORNING FOR
NEZ038-059-069>071.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1023 AM EDT TUE JUL 30 2013
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE ACROSS SOUTHERN QUEBEC WILL DEPART
NORTHEASTWARD THIS MORNING ALLOWING HIGH PRESSURE TO BUILD INTO THE
NORTH COUNTRY THIS AFTERNOON THROUGH WEDNESDAY. AN ISOLATED RAIN
SHOWER IS POSSIBLE THIS MORNING...FOLLOWED BY MOSTLY CLEAR AND
PLEASANT WEATHER CONDITIONS TONIGHT AND WEDNESDAY. THE NEXT UPPER
TROUGH APPROACHING FROM THE GREAT LAKES REGION WILL BRING SCATTERED
SHOWERS AND THUNDERSTORMS TO THE REGION THURSDAY AFTERNOON AND
EVENING. ADDITIONAL SHOWERS ARE POSSIBLE FRIDAY AND SATURDAY AS A
BROAD UPPER LEVEL TROUGH BECOMES ESTABLISHED OVER NEW YORK AND NEW
ENGLAND. TEMPERATURES WILL REACH THE UPPER 70S TODAY...LOW 80S ON
WEDNESDAY...AND THEN GENERALLY IN THE MID TO UPPER 70S THROUGH THE
REMAINDER OF THE WEEK...WHICH IS SLIGHTLY BELOW AVERAGE FOR THE
START OF AUGUST.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 1019 AM EDT TUESDAY...MINOR ADJUSTMENTS TO SKY COVER AND
TEMPS AS WE PROGRESS INTO THE LATE MORNING HOURS. OTW INHERITED
FORECAST REMAINS IN GOOD SHAPE. MAINTAINED PRIOR IDEA OF AN
OUTSIDE SHOT OF A FEW LIGHT SHOWERS OR SPRINKLES ACROSS NERN VT
TODAY...BUT LATEST PROXY RAP SOUNDINGS SHOW A DRY AND DEEPLY MIXED
PBL TO NEARLY 700 MB TODAY SO ANY ACTIVITY WOULD BE LIGHT AT BEST
WITH MOST AREAS...EVEN IN THESE LOCALES REMAINING DRY. HAVE A
GREAT DAY.
PREVIOUS DISCUSSION: EARLY MORNING WATER VAPOR IMAGERY REVEALS
COMPACT MID-LEVEL VORT CENTERED ACROSS SWRN QUEBEC ABOUT 100 MI
NORTH OF KMSS AT 07Z. THIS SYSTEM WILL CONTINUE TO TRANSLATE ENEWD
TODAY AND GENERALLY AWAY FROM THE NORTH COUNTRY. LINGERING/ISOLD
-SHRA NEAR THE INTL BORDER PER CXX 88-D SHOULD GENERALLY END BY
15-16Z AS DRIER AIR WORKS IN ON DEVELOPING NW FLOW BEHIND THE VORT
MAX /MID-LEVEL TROUGH. ALSO ANTICIPATING PRONOUNCED MID-LEVEL
HEIGHT RISES THIS AFTN. INSOLATIONAL EFFECTS AND SUBSIDENCE ALOFT
SHOULD ALLOW SKIES TO TREND MOSTLY SUNNY THIS AFTN. IT APPEARS
AFTN VALLEY HIGHS WILL REACH THE UPR 70S. LIGHT AND VARIABLE WINDS
EARLY THIS MORNING WILL BECOME W-NW AT 5-10 MPH LATE MORNING THRU
AFTN. NOT MUCH FOG AROUND EARLY THIS MORNING DUE TO CLOUD
COVER...AND ANY PATCHY FOG DEVELOPMENT BETWEEN NOW AND SUNRISE
WILL DISSIPATE BY 12Z.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH THURSDAY/...
AS OF 329 AM EDT TUESDAY...A QUIET AND DRY STRETCH OF WEATHER IS EXPECTED
TONIGHT...WEDNESDAY...AND WEDNESDAY NIGHT. SHORTWAVE RIDGING
TRANSLATES FROM W-E ACROSS THE REGION AND WEAK SFC RIDGE WILL BRING
TRANQUIL WEATHER AND LIGHT WIND CONDITIONS. LOW TEMPERATURES
TONIGHT WILL GENERALLY BE IN THE 50S. A FEW THIN MID-UPR CLOUDS ARE
POSSIBLE...BUT RADIATIONAL COOLING SHOULD BE SUFFICIENT FOR PATCHY
FOG DEVELOPMENT IN THE FAVORED SPOTS WITHIN THE NRN ADIRONDACK
REGION AND ACROSS THE RIVER VALLEYS OF CENTRAL/ERN VT 06-12Z WED.
WEDNESDAY WILL BE OUR WARMEST DAY THIS WEEK WITH AFTN HIGHS IN THE
LOW 80S MOST SECTIONS. HUMIDITY LEVELS WILL REMAIN MODEST WITH
DEWPOINTS IN THE MID-UPR 50S. A FEW PASSING HIGH CLOUDS
ANTICIPATED BUT GENERALLY MOSTLY SUNNY WITH S-SW WINDS 5-10 MPH.
CHANGES ARRIVE ON THURSDAY AS MID-UPPER TROPOSPHERIC FLOW BECOMES
INCREASINGLY CYCLONIC IN RESPONSE TO SHORTWAVE TROUGH TRANSLATING
EWD FROM THE GREAT LAKES REGION. BANDS OF SHOWERS WILL PRECEDE THE
TROUGH AXIS...LIKELY REACHING NRN NY DURING THE MID-LATE MORNING
AND DEVELOPING ACROSS VT IN THE AFTN. CAPE VALUES OF 500-1000 J/KG
ARE ANTICIPATED...AND WILL CONTRIBUTE TO POTENTIAL FOR EMBEDDED
TSTMS THURSDAY AFTN/EVE. CAPE PROFILES ARE NARROW AND DON/T SUGGEST
A SVR THREAT AT THIS TIME. A FEW STORMS MAY CONTAIN BRIEF HEAVY
RAINFALL AND CG LIGHTNING AND WILL PUT MENTION OF THIS IN THE
HAZARDOUS WEATHER OUTLOOK. POPS THURSDAY AFTN/EVE REACH 70-80
PERCENT AND CONTINUE INTO THURSDAY NIGHT. HIGH TEMPERATURES ON
THURSDAY WILL BE AROUND 80F IN VERMONT WITH PARTIAL SUNSHINE EARLY.
ACROSS NY...EARLIER ARRIVAL OF SHOWERS LIKELY KEEPS TEMPS IN THE
MID 70S FOR DAYTIME HIGHS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 350 AM EDT TUESDAY...OVERALL MODELS IN GOOD AGREEMENT WITH
LARGE SCALE PATTERN FOR DAYS 4 THRU 7...WHICH SUPPORTS MID/UPPER
LVL TROF ACRS THE NE CONUS. THIS SYNOPTIC SETUP WL RESULT IN BLW NORMAL
TEMPS AND SEVERAL CHCS FOR PRECIP THRU THE PERIOD. WL CONT TO
MENTION LIKELY POPS ON THURS NIGHT ASSOCIATED WITH SFC BOUNDARY
AND 5H VORT INTERACTING WITH FAVORABLE 850 TO 500MB RH PROFILES.
ON FRIDAY INTO SATURDAY...SEVERAL EMBEDDED VORTS IN FLW ALOFT WL
MOVE ACRS OUR CENTRAL/NORTHERN CWA...WITH ADDITIONAL CHCS FOR
PRECIP. WL MENTION HIGHEST CHC POPS ACRS THE MTNS OF NNY AND VT ON
FRIDAY/SATURDAY. ECMWF SHOWS A PROGRESSIVE NW FLW WITH ADDITIONAL ENERGY
IMPACTING OUR CWA ON SUNDAY INTO MONDAY...WHILE THE GFS SHOWS SOME
DRYING. WL TREND TWD A DRIER FCST FOR EARLY NEXT WEEK...AS WEAK
RIDGE BUILDS INTO OUR FA. PROGGED 85H TEMPS START AROUND 10C...BUT
COOL BTWN 4C AND 6C BY EARLY NEXT WEEK...SUPPORTING HIGHS MAINLY
IN THE U60S MTNS TO UPPER 70S VALLEYS.
&&
.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
THROUGH 12Z WEDNESDAY...VFR CONDITIONS AT ALL TAF SITES EXCEPT
IFR/MVFR AT SLK...WHICH WL LIFT TO VFR BY 13Z THIS MORNING. RAP13
SOUNDINGS SHOWS RH BTWN 925MB AND 700MB TODAY...WHICH WL HLEP IN
THE DEVELOPMENT OF A STRATOCUMULUS DECK...ESPECIALLY AT MPV/SLK.
WL MENTION A BROKEN DECK AT 4500 FEET. SOUTHWEST WINDS WL SLOWLY
SHIFT TO THE NORTHWEST BY MID MORNING AT 5 TO 10 KNOTS. CLOUDS WL
DECREASE THIS EVENING WITH LIGHT AND VARIABLE WINDS. SOME FOG/BR
WL BE POSSIBLE AT SLK/MPV AFT 06Z...WITH OCCASIONAL IFR
CONDITIONS.
OUTLOOK 12Z WEDNESDAY THROUGH SATURDAY...VFR CONDITIONS WL
PREVAIL FOR WEDS INTO THURSDAY WITH SFC HIGH PRES. CLOUDS WL
THICKEN WITH RAIN SHOWERS DEVELOPING BY THURSDAY MIDDAY...ALONG
WITH THE POTENTIAL FOR MVFR/IFR IN THE HEAVIER SHOWERS. SYSTEM
SHIFTS EAST OF TAF SITES BY FRIDAY...WITH VFR CONDITIONS EXPECTED
INTO SATURDAY.
&&
.EQUIPMENT...
AS OF 1230 AM EDT TUESDAY...THE WSR-88D DOPPLER RADAR AT FORT DRUM NY
(KTYX) REMAINS INOPERABLE AS TECHS AWAIT NECESSARY REPLACEMENT
PARTS. THE PARTS ARE NOT EXPECTED TO BE ON SITE UNTIL WEDNESDAY OR
THURSDAY. WE APOLOGIZE FOR THE RADAR OUTAGE AND WILL PROVIDED
AN UPDATED REPAIR TIMELINE AS IT BECOMES AVAILABLE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...JMG/BANACOS
SHORT TERM...BANACOS
LONG TERM...TABER
AVIATION...TABER
EQUIPMENT...BTV
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
218 PM CDT TUE JUL 30 2013
.DISCUSSION...
931 AM CDT
UPDATED MORNING POP/WEATHER GRIDS TO ACCOUNT FOR CURRENT RADAR
TRENDS AND ALSO BOOSTED POPS THIS AFTERNOON...MAINLY FOR SOUTH AND
SOUTHWEST PORTIONS OF THE AREA. FORECAST SOUNDINGS FROM ORD ARE
STILL SHOWING CONSIDERABLE DRY AIR AROUND 800MB FOR THE METRO
AREA...BUT OBVIOUSLY THE AIR IS FAIRLY WELL SATURATED FARTHER TO
THE SOUTHWEST. THE CURRENT TRENDS ARE DEPICTED NICELY BY MOISTURE
CONVERGENCE FIELDS IN THE RAP MODEL...SO HAVE LEANED TOWARD THAT
EVOLUTION FOR THE REST OF THE DAY. MAY NEED FURTHER UPDATES IF
ACTIVITY SHOWS GOOD SIGNS OF HOLDING TOGETHER LATER INTO THE
AFTERNOON. GIVEN EXISTING AND FORECAST CAPE TRENDS AND SOUNDING
PROFILES...MAY ALSO NEED TO ADD MENTION OF THUNDERSTORMS LATER
TODAY...BUT MID LEVEL LAPSE RATES ARE ONLY MARGINALLY FAVORABLE.
LENNING
//PREV DISCUSSION...
323 AM CDT
TODAY...
SFC RIDGING CONTINUES TO BE AN INFLUENCE ON THE REGION...DESPITE
DRIFTING EAST OF THE CWFA AND BECOMING CENTERED OVER THE EASTERN
OHIO VALLEY THIS MORNING. IR IMAGERY DEPICTS A COMPLEX OF
THUNDERSTORMS ACROSS THE SOUTHERN PLAINS...WITH REGIONAL RADAR
SHOWING PRECIP RETURNS LIFTING INTO NORTHEAST MISSOURI/SOUTHEAST
IOWA. FOR MUCH OF THE DAY TODAY EXPECT SFC RIDGING TO CONTINUE TO
KEEP PRECIP WEST/SOUTHWEST OF THE CWFA. GUIDANCE HOLDS ONTO THE
SOUTHEAST FLOW AT THE SFC...WITH SOUNDINGS SUGGESTING CONSIDERABLE
DRY AIR THRU 15Z THEN SLOWLY MOISTENING FROM THE TOP DOWN. PWAT
VALUES SLOWLY INCREASE...HOVERING ARND 1.8" BY LATE THIS AFTN/EVE.
BY 18Z EXPECT SCATTERED PRECIP TO BEGIN PUSHING OVER THE CWFA. BASED
ON THE SOUNDINGS CONVECTIVE POTENTIAL REMAINS VERY LOW...EXCEPT FOR
FAR SOUTHERN AREAS OF THE CWFA. OTHERWISE EXPECT PRECIP TO REMAIN
LIGHT IN INTENSITY AND MINIMAL COVERAGE.
WITH GRADUAL THICKENING OF THE CLOUD SHIELD...TEMPS WILL INITIALLY
WARM THEN THE RATE OF CLIMB WILL BEGIN TO SLOW GIVEN THE INCREASED
MOISTURE IN THE ATMOSPHERE. STILL THINK THAT TEMPS WILL WARM TO THE
MID 70S...HOWEVER IF CLOUDS CAN THICKEN FASTER THIS MORNING TEMPS
MAY STRUGGLE TO WARM BEYOND THE LOW 70S.
CONFIDENCE...MEDIUM.
TONIGHT THROUGH WEDNESDAY...
WEAK SHORTWAVE CONTINUES TO LIFT NORTHEAST ACROSS MISSOURI LATE THIS
AFTN/EARLY EVE...WHILE ANTI-CYCLONIC FLOW OVER THE OHIO VALLEY
CONTINUES TO PROVIDE A DRY INFLUENCE ON THE NEAR SFC ENVIRONMENT
ACROSS NORTHERN IL/NORTHWEST IN. SFC WINDS APPEAR TO HOLD FROM THE
SOUTHEAST...AND UNDER A LIGHT GRADIENT WILL LIKELY BE LESS THAN 10
MPH. THIS COULD BE JUST ENOUGH OF A DRY FLOW IN THE LLVLS TO HOLD
FULL SATURATION OF THE PROFILE. GUIDANCE DOES INDICATE A SLOW
MOISTENING OF THE LOW/MID LVLS AFT 21Z THIS AFTN...WITH PWAT VALUES
STEADILY INCREASING TO ARND 1.5-1.8". THE TREND HAS BEEN DRIER AND
FURTHER SOUTH WITH THIS SYSTEM...HOWEVER JUST ENOUGH MOISTURE COULD
LIFT OVERHEAD AND WITH SOME OMEGA OR LIFT PRESENT...SPRINKLES/LIGHT
SHRA COULD DEVELOP LATE THIS EVENING/OVERNIGHT. LOCAL HI-RES WRF
SOLUTION KEEPS ALL PRECIP TO THE SOUTH OF A PONTIAC TO FOWLER LINE.
HAVE TRIMMED BACK ON POPS TO THE HIGH TEENS...AND EXPECT COVERAGE TO
BE MINIMAL WITH PRECIP TONIGHT. IN ADDITION DROPLET SIZE WILL BE
SMALL AS WELL...WHICH COULD TRANSLATE INTO DRIZZLE OR CHANGING
PRECIP TO SPRINKLES INSTEAD OF SHOWERS.
WITH A 500MB WAVE RATHER FLAT...THIS SYSTEM WILL REMAIN PROGRESSIVE
AND PUSH TO THE EAST BY WED MORNING. ALONG THE BACK EDGE OF THE
DEPARTING WEAK SFC WAVE IT APPEARS SOME DIFLUENT FLOW TRIES TO
DEVELOP AND COULD BRING A BRIEF END TO THE PRECIP BY DAYBREAK WED.
THEN THE FOCUS TURNS TOWARDS AN ADVANCING FRONTAL BOUNDARY THAT WILL
BE SLIDING INTO THE UPPER MIDWEST EARLY WED.
LLVL FLOW WILL BECOME SOUTHERLY TO SOUTHWESTERLY AHEAD OF THE COLD
FRONT...WITH MARGINAL INSTABILITY DEVELOPING IN THE AFTN HOURS WED.
WITH THE LACK OF STRONG SHEAR AND MODEL SOUNDINGS INDICATING SOME
DRY AIR IN THE NEAR SFC...IT IS CONCEIVABLE THAT MUCH OF WED COULD
BE DRY. AS PREVIOUSLY NOTED IN REGARDS TO THE LCL HI-RES WRF...THIS
SOLUTION CONTINUES THE DRY THEME FOR WED. AT THIS POINT HAVE ONLY
TRIMMED BACK ON POPS FOR WED...AND FOCUSED THE TIMING TOWARDS THE
AFTN/EVE HOURS OR CLOSER TO FROPA. 500MB TROUGH AXIS APPEARS TO PUSH
INTO THE WESTERN GREAT LAKES ARND 00Z THUR...WITH DIMINISHING LLVL
MOISTURE. MID-LVL SHEAR WILL INCREASE AS THE BNDRY NEARS...AND WITH
MARGINAL INSTABILITY COULD ALLOW SOME ISOLATED THUNDERSTORMS TO
DEVELOP LATE WED AFTN.
IN REGARDS TO TEMPS TONIGHT...EXPECT CONSIDERABLE CLOUD COVER TO
HOLD TEMPS SLIGHTLY WARMER OR IN THE MID 60S AWAY FROM LAKE MICHIGAN
AND UPR 60S CLOSER TO THE LAKE. THEN FOR WED TEMPS WILL BE SLIGHTLY
WARMER AND CLOSER TO 80 DEG. IF THE SOUTH/SOUTHWEST FLOW IS SLIGHTLY
STRONGER WED IN ADVANCE OF THE FRONT...TEMPS MAY BE ABLE TO WARM
FURTHER OR 80-83 DEG.
CONFIDENCE...MEDIUM.
CONFIDENCE IN PRECIP...LOW.
THURSDAY THROUGH FRIDAY...
500MB TROUGH QUICKLY SLIDES OVERHEAD WITH ANTI-CYCLONIC FLOW
BUILDING INTO THE REGION FROM THE WEST. THIS WILL AID IN PROVIDING
DRY WEATHER FOR THUR/THUR NIGHT. SFC RIDGE PUSHES FURTHER SOUTH
ACROSS THE TENN VALLEY FRI...WHILE A LOBE OF VORTICITY IS PROGGED TO
SLIDE SOUTHEAST ACROSS THE WESTERN GREAT LAKES FRI. THIS APPEARS TO
BE ASSOCIATED WITH A FRONTAL BOUNDARY...WHICH MAY HAVE SOME PRECIP
ACCOMPANYING FROPA FRI/FRI EVE. ALTHOUGH THE SETUP LOOKS MORE
FAVORABLE FOR A DRY FROPA AS ANTI-CYCLONIC FLOW WILL BE DEPARTING
WITH YET ANOTHER ANTI-CYCLONIC FLOW SLIDING SOUTHEAST ACROSS THE
NORTHERN PLAINS/UPPER MIDWEST FRI NIGHT.
TEMPS CONTINUE TO BE UNSEASONABLY COOL...WITH AFTN HIGHS STRUGGLING
TO WARM BEYOND THE UPR 70S IN MANY LOCATIONS. A FEW SITES MAY TOUCH
80 DEG FRI AFTN.
CONFIDENCE...MEDIUM.
SATURDAY THROUGH MONDAY...
EXTENDED PERIODS CONTINUE TO FEATURE A COOL NORTHWEST SETUP WITH
ENSEMBLES DEMONSTRATING MINIMAL NOISE OR DIFFERENCES. THE STRENGTH
OF THE DOWNSTREAM RIDGE OVER THE CANADIAN MARITIME DOES EXHIBIT SOME
WEAKENING SUN...WHICH SHOULD ALLOW THE GREAT LAKES TROUGH TO WEAKEN
AND PUSH EAST. HOWEVER PROGRESSING TOWARDS THE FINAL FEW
PERIODS...HIGH LATITUDE RIDGING IS PROGGED TO DEVELOP OVER THE NORTH
ATLANTIC AND STRETCH WEST ACROSS WESTERN CANADA. IF THIS SOLUTION
VERIFIES...FLOW ACROSS THE GREAT LAKES REGION WILL LIKELY REMAIN IN
A UNSEASONABLY COOL SETUP.
OPERATIONAL SOLUTIONS HAVE SFC RIDGING BUILDING IN FOR SAT AND
LINGERING THRU SUN NGT...WHICH WILL PROVIDE DRY WEATHER. THEN THE
500MB FLOW BEGINS TO FLATTEN AND BECOME MORE FLUID...WITH A FRONTAL
BOUNDARY AND A WEAK SYSTEM APPROACHING THE REGION TOWARDS THE FINAL
PERIODS WITH A CHANCE OF PRECIP FOR EARLY NEXT WEEK.
CONFIDENCE...MEDIUM/HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* SCATTERED -SHRA OVER AREA TIL LATER AFTERNOON.
* ANOTHER PERIOD OF -SHRA/-RA MID EVENING INTO LATE NIGHT.
* VFR DETERIORATING TO MVFR WITH EVENING PRECIP.
* CONTINUED DETERIORATION FROM MVFR TO IFR OVERNIGHT THEN GRADUAL
IMPROVEMENT BACK THROUGH MVFR TO VFR DURING EARLY TO MID WED
AFTERNOON.
TRS
//DISCUSSION...UPDATED 18Z...
DISTURBANCE CONTINUES TO MOVE E FROM IA AND MO TO MS RIVER IN
ZONAL FLOW AT MIDDAY. WATER VAPOR SATELLITE LOOP SHOWS A COUPLE
MINOR DISTURBANCES FURTHER UPSTREAM OVER EASTERN NE AND EASTERN WY
ALSO MOVING E WITH THE ZONAL FLOW WITH A STRONGER ONE MOVING
ACROSS THE NORTHERN PLAINS TOWARD THE UPPER MIDWEST. MODELS
SUGGEST THAT IT WILL PHASE WITH THE MID MS VALLEY DISTURBANCE WITH
THE NORTHERN PORTION OF THE RESULTING MID LEVEL TROUGH MOVING
ACROSS NORTHERN IL DURING THE NIGHT.
MODELS HANDLE SURFACE LOW ASSOCIATED WITH THE MID LEVEL TROUGH
DIFFERENTLY WITH GEM AND NAM MOVING IT E OR ENE FROM W CENTRAL IL
OVERNIGHT WHILE 30.00Z ECMWF AND 12Z GFS KEEP THE LOW CENTER IN
SOUTHERN IL. ISENTROPIC SURFACES SHOW MODERATE UPGLIDE ACROSS THE
LOCAL AREA TONIGHT AND QPF FIELDS INDICATE LIGHT PRECIP
ACCUMULATIONS RESULTING SO FEEL A PERIOD OF TEMPO -SHRA WARRANTED
FOR MID EVE INTO LATE OVERNIGHT.
AREAS OF MVFR HAS SPREAD INTO NE AND N CENTRAL IL LATE MORNING-
EARLY AFTERNOON WITH AREAS OF IFR FURTHER TO THE W...MAINLY ACROSS
WESTERN AND SOUTHERN IA. MOISTURE PROGS INDICATE THAT THE LOWER
LEVELS MOISTEN UP BY EARLY THIS EVENING. WITH MOIST LOW LEVELS
FROM SHOWERS AND LIGHT LOW LEVEL FLOW OVERNIGHT ANTICIPATE
CEILINGS TO FALL TO IFR. DURING THE MID MORNING WED EXPECT
IMPROVEMENT TO MVFR AND EVENTUALLY VFR THOUGH TIMING NOT VERY
CERTAIN DUE TO THE VARYING HANDLING OF SURFACE FEATURES AND THEIR
INFLUENCE ON ON QUICKLY N AND NW LOW LEVEL FLOW GETS ESTABLISHED
ACROSS THE REGION.
TRS
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE ALL ELEMENTS EARLY AFTERNOON.
* MODERATE CONFIDENCE IN TIMING ONSET OF MVFR AND IFR CONDITIONS
LATE AFTERNOON AND TONIGHT.
* HIGH CONFIDENCE THAT IF ANY ISOLD TS DEVELOP THIS AFTERNOON
THEN WILL REMAIN S OF MDW AND ORD.
* LOW CONFIDENCE IN TIMING OF IMPROVEMENT TO MVFR THEN VFR DURING
WED MORNING.
TRS
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
* WEDNESDAY NIGHT...CHANCE OF TSRA.
* THURSDAY...DRY/VFR.
* FRIDAY...CHANCE OF TSRA.
* SATURDAY AND SUNDAY...DRY/VFR.
* MONDAY...CHANCE OF TSRA.
&&
.MARINE...
215 PM...BROAD HIGH PRESSURE EXTENDS FROM SOUTHERN ONTARIO THROUGH
THE OHIO VALLEY TO THE SERN CONUS WHILE LOW PRESSURE DEVELOPS OVER
NRN WINNIPEG WITH A WEAK FRONTAL TROUGH EXTENDING SOUTH INTO THE
NORTHERN PLAINS. GENERALLY SOUTHERLY WINDS WILL PERSIST OVER THE
LAKE WHILE THE HIGH SLOWLY MOVES TO THE EAST AND THE TROUGH AND
ASSOCIATED COLD FRONT MOVE INTO THE UPPER MISSISSIPPI VALLEY
TOMORROW. IN THE MEAN TIME...WEAK LOW PRESSURE OVER THE SRN PLAINS
WILL TRACK INTO SRN IL TOMORROW...TURNING WINDS OVER THE SRN
PORTIONS OF THE LAKE LIGHT AND NELY. A MODEST PRESSURE GRADIENT
WILL REMAIN IN PLACE OVER THE NRN PORTIONS OF THE LAKE...KEEPING
SWLY WINDS ARND 15-20KT INTO TOMORROW EVENING. THE WEAK COLD FRONT
WILL PUSH ACROSS THE LAKE WEDNESDAY NIGHT AND WINDS OVER THE LAKE
WILL GRADUALLY TURN NWLY. WITH A LACK OF STRONG COLD ADVECTION OR
A STRONG PRESSURE RISE-FALL COUPLET WITH THE FROPA...WINDS SHOULD
ONLY INCREASE TO 15-20KT FOLLOWING THE FROPA LATE WEDNESDAY NIGHT
AND EARLY THURSDAY MORNING BEFORE BACKING WLY AND DIMINISHING TO
ARND 10KT. WEAK HIGH PRESSURE WILL SETTLE INTO THE NRN PLAINS
THURSDAY NIGHT AND FRIDAY AND SPREAD EAST ACROSS THE WESTERN GREAT
LAKES THROUGH THE WEEKEND...KEEPING WINDS GENERALLY WESTERLY AND
IN THE 5-10KT RANGE.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
120 PM CDT TUE JUL 30 2013
.DISCUSSION...
931 AM CDT
UPDATED MORNING POP/WEATHER GRIDS TO ACCOUNT FOR CURRENT RADAR
TRENDS AND ALSO BOOSTED POPS THIS AFTERNOON...MAINLY FOR SOUTH AND
SOUTHWEST PORTIONS OF THE AREA. FORECAST SOUNDINGS FROM ORD ARE
STILL SHOWING CONSIDERABLE DRY AIR AROUND 800MB FOR THE METRO
AREA...BUT OBVIOUSLY THE AIR IS FAIRLY WELL SATURATED FARTHER TO
THE SOUTHWEST. THE CURRENT TRENDS ARE DEPICTED NICELY BY MOISTURE
CONVERGENCE FIELDS IN THE RAP MODEL...SO HAVE LEANED TOWARD THAT
EVOLUTION FOR THE REST OF THE DAY. MAY NEED FURTHER UPDATES IF
ACTIVITY SHOWS GOOD SIGNS OF HOLDING TOGETHER LATER INTO THE
AFTERNOON. GIVEN EXISTING AND FORECAST CAPE TRENDS AND SOUNDING
PROFILES...MAY ALSO NEED TO ADD MENTION OF THUNDERSTORMS LATER
TODAY...BUT MID LEVEL LAPSE RATES ARE ONLY MARGINALLY FAVORABLE.
LENNING
//PREV DISCUSSION...
323 AM CDT
TODAY...
SFC RIDGING CONTINUES TO BE AN INFLUENCE ON THE REGION...DESPITE
DRIFTING EAST OF THE CWFA AND BECOMING CENTERED OVER THE EASTERN
OHIO VALLEY THIS MORNING. IR IMAGERY DEPICTS A COMPLEX OF
THUNDERSTORMS ACROSS THE SOUTHERN PLAINS...WITH REGIONAL RADAR
SHOWING PRECIP RETURNS LIFTING INTO NORTHEAST MISSOURI/SOUTHEAST
IOWA. FOR MUCH OF THE DAY TODAY EXPECT SFC RIDGING TO CONTINUE TO
KEEP PRECIP WEST/SOUTHWEST OF THE CWFA. GUIDANCE HOLDS ONTO THE
SOUTHEAST FLOW AT THE SFC...WITH SOUNDINGS SUGGESTING CONSIDERABLE
DRY AIR THRU 15Z THEN SLOWLY MOISTENING FROM THE TOP DOWN. PWAT
VALUES SLOWLY INCREASE...HOVERING ARND 1.8" BY LATE THIS AFTN/EVE.
BY 18Z EXPECT SCATTERED PRECIP TO BEGIN PUSHING OVER THE CWFA. BASED
ON THE SOUNDINGS CONVECTIVE POTENTIAL REMAINS VERY LOW...EXCEPT FOR
FAR SOUTHERN AREAS OF THE CWFA. OTHERWISE EXPECT PRECIP TO REMAIN
LIGHT IN INTENSITY AND MINIMAL COVERAGE.
WITH GRADUAL THICKENING OF THE CLOUD SHIELD...TEMPS WILL INITIALLY
WARM THEN THE RATE OF CLIMB WILL BEGIN TO SLOW GIVEN THE INCREASED
MOISTURE IN THE ATMOSPHERE. STILL THINK THAT TEMPS WILL WARM TO THE
MID 70S...HOWEVER IF CLOUDS CAN THICKEN FASTER THIS MORNING TEMPS
MAY STRUGGLE TO WARM BEYOND THE LOW 70S.
CONFIDENCE...MEDIUM.
TONIGHT THROUGH WEDNESDAY...
WEAK SHORTWAVE CONTINUES TO LIFT NORTHEAST ACROSS MISSOURI LATE THIS
AFTN/EARLY EVE...WHILE ANTI-CYCLONIC FLOW OVER THE OHIO VALLEY
CONTINUES TO PROVIDE A DRY INFLUENCE ON THE NEAR SFC ENVIRONMENT
ACROSS NORTHERN IL/NORTHWEST IN. SFC WINDS APPEAR TO HOLD FROM THE
SOUTHEAST...AND UNDER A LIGHT GRADIENT WILL LIKELY BE LESS THAN 10
MPH. THIS COULD BE JUST ENOUGH OF A DRY FLOW IN THE LLVLS TO HOLD
FULL SATURATION OF THE PROFILE. GUIDANCE DOES INDICATE A SLOW
MOISTENING OF THE LOW/MID LVLS AFT 21Z THIS AFTN...WITH PWAT VALUES
STEADILY INCREASING TO ARND 1.5-1.8". THE TREND HAS BEEN DRIER AND
FURTHER SOUTH WITH THIS SYSTEM...HOWEVER JUST ENOUGH MOISTURE COULD
LIFT OVERHEAD AND WITH SOME OMEGA OR LIFT PRESENT...SPRINKLES/LIGHT
SHRA COULD DEVELOP LATE THIS EVENING/OVERNIGHT. LOCAL HI-RES WRF
SOLUTION KEEPS ALL PRECIP TO THE SOUTH OF A PONTIAC TO FOWLER LINE.
HAVE TRIMMED BACK ON POPS TO THE HIGH TEENS...AND EXPECT COVERAGE TO
BE MINIMAL WITH PRECIP TONIGHT. IN ADDITION DROPLET SIZE WILL BE
SMALL AS WELL...WHICH COULD TRANSLATE INTO DRIZZLE OR CHANGING
PRECIP TO SPRINKLES INSTEAD OF SHOWERS.
WITH A 500MB WAVE RATHER FLAT...THIS SYSTEM WILL REMAIN PROGRESSIVE
AND PUSH TO THE EAST BY WED MORNING. ALONG THE BACK EDGE OF THE
DEPARTING WEAK SFC WAVE IT APPEARS SOME DIFLUENT FLOW TRIES TO
DEVELOP AND COULD BRING A BRIEF END TO THE PRECIP BY DAYBREAK WED.
THEN THE FOCUS TURNS TOWARDS AN ADVANCING FRONTAL BOUNDARY THAT WILL
BE SLIDING INTO THE UPPER MIDWEST EARLY WED.
LLVL FLOW WILL BECOME SOUTHERLY TO SOUTHWESTERLY AHEAD OF THE COLD
FRONT...WITH MARGINAL INSTABILITY DEVELOPING IN THE AFTN HOURS WED.
WITH THE LACK OF STRONG SHEAR AND MODEL SOUNDINGS INDICATING SOME
DRY AIR IN THE NEAR SFC...IT IS CONCEIVABLE THAT MUCH OF WED COULD
BE DRY. AS PREVIOUSLY NOTED IN REGARDS TO THE LCL HI-RES WRF...THIS
SOLUTION CONTINUES THE DRY THEME FOR WED. AT THIS POINT HAVE ONLY
TRIMMED BACK ON POPS FOR WED...AND FOCUSED THE TIMING TOWARDS THE
AFTN/EVE HOURS OR CLOSER TO FROPA. 500MB TROUGH AXIS APPEARS TO PUSH
INTO THE WESTERN GREAT LAKES ARND 00Z THUR...WITH DIMINISHING LLVL
MOISTURE. MID-LVL SHEAR WILL INCREASE AS THE BNDRY NEARS...AND WITH
MARGINAL INSTABILITY COULD ALLOW SOME ISOLATED THUNDERSTORMS TO
DEVELOP LATE WED AFTN.
IN REGARDS TO TEMPS TONIGHT...EXPECT CONSIDERABLE CLOUD COVER TO
HOLD TEMPS SLIGHTLY WARMER OR IN THE MID 60S AWAY FROM LAKE MICHIGAN
AND UPR 60S CLOSER TO THE LAKE. THEN FOR WED TEMPS WILL BE SLIGHTLY
WARMER AND CLOSER TO 80 DEG. IF THE SOUTH/SOUTHWEST FLOW IS SLIGHTLY
STRONGER WED IN ADVANCE OF THE FRONT...TEMPS MAY BE ABLE TO WARM
FURTHER OR 80-83 DEG.
CONFIDENCE...MEDIUM.
CONFIDENCE IN PRECIP...LOW.
THURSDAY THROUGH FRIDAY...
500MB TROUGH QUICKLY SLIDES OVERHEAD WITH ANTI-CYCLONIC FLOW
BUILDING INTO THE REGION FROM THE WEST. THIS WILL AID IN PROVIDING
DRY WEATHER FOR THUR/THUR NIGHT. SFC RIDGE PUSHES FURTHER SOUTH
ACROSS THE TENN VALLEY FRI...WHILE A LOBE OF VORTICITY IS PROGGED TO
SLIDE SOUTHEAST ACROSS THE WESTERN GREAT LAKES FRI. THIS APPEARS TO
BE ASSOCIATED WITH A FRONTAL BOUNDARY...WHICH MAY HAVE SOME PRECIP
ACCOMPANYING FROPA FRI/FRI EVE. ALTHOUGH THE SETUP LOOKS MORE
FAVORABLE FOR A DRY FROPA AS ANTI-CYCLONIC FLOW WILL BE DEPARTING
WITH YET ANOTHER ANTI-CYCLONIC FLOW SLIDING SOUTHEAST ACROSS THE
NORTHERN PLAINS/UPPER MIDWEST FRI NIGHT.
TEMPS CONTINUE TO BE UNSEASONABLY COOL...WITH AFTN HIGHS STRUGGLING
TO WARM BEYOND THE UPR 70S IN MANY LOCATIONS. A FEW SITES MAY TOUCH
80 DEG FRI AFTN.
CONFIDENCE...MEDIUM.
SATURDAY THROUGH MONDAY...
EXTENDED PERIODS CONTINUE TO FEATURE A COOL NORTHWEST SETUP WITH
ENSEMBLES DEMONSTRATING MINIMAL NOISE OR DIFFERENCES. THE STRENGTH
OF THE DOWNSTREAM RIDGE OVER THE CANADIAN MARITIME DOES EXHIBIT SOME
WEAKENING SUN...WHICH SHOULD ALLOW THE GREAT LAKES TROUGH TO WEAKEN
AND PUSH EAST. HOWEVER PROGRESSING TOWARDS THE FINAL FEW
PERIODS...HIGH LATITUDE RIDGING IS PROGGED TO DEVELOP OVER THE NORTH
ATLANTIC AND STRETCH WEST ACROSS WESTERN CANADA. IF THIS SOLUTION
VERIFIES...FLOW ACROSS THE GREAT LAKES REGION WILL LIKELY REMAIN IN
A UNSEASONABLY COOL SETUP.
OPERATIONAL SOLUTIONS HAVE SFC RIDGING BUILDING IN FOR SAT AND
LINGERING THRU SUN NGT...WHICH WILL PROVIDE DRY WEATHER. THEN THE
500MB FLOW BEGINS TO FLATTEN AND BECOME MORE FLUID...WITH A FRONTAL
BOUNDARY AND A WEAK SYSTEM APPROACHING THE REGION TOWARDS THE FINAL
PERIODS WITH A CHANCE OF PRECIP FOR EARLY NEXT WEEK.
CONFIDENCE...MEDIUM/HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* SCATTERED -SHRA OVER AREA TIL LATER AFTERNOON.
* ANOTHER PERIOD OF -SHRA/-RA MID EVENING INTO LATE NIGHT.
* VFR DETERIORATING TO MVFR WITH EVENING PRECIP.
* CONTINUED DETERIORATION FROM MVFR TO IFR OVERNIGHT THEN GRADUAL
IMPROVEMENT BACK THROUGH MVFR TO VFR DURING EARLY TO MID WED
AFTERNOON.
TRS
//DISCUSSION...UPDATED 18Z...
DISTURBANCE CONTINUES TO MOVE E FROM IA AND MO TO MS RIVER IN
ZONAL FLOW AT MIDDAY. WATER VAPOR SATELLITE LOOP SHOWS A COUPLE
MINOR DISTURBANCES FURTHER UPSTREAM OVER EASTERN NE AND EASTERN WY
ALSO MOVING E WITH THE ZONAL FLOW WITH A STRONGER ONE MOVING
ACROSS THE NORTHERN PLAINS TOWARD THE UPPER MIDWEST. MODELS
SUGGEST THAT IT WILL PHASE WITH THE MID MS VALLEY DISTURBANCE WITH
THE NORTHERN PORTION OF THE RESULTING MID LEVEL TROUGH MOVING
ACROSS NORTHERN IL DURING THE NIGHT.
MODELS HANDLE SURFACE LOW ASSOCIATED WITH THE MID LEVEL TROUGH
DIFFERENTLY WITH GEM AND NAM MOVING IT E OR ENE FROM W CENTRAL IL
OVERNIGHT WHILE 30.00Z ECMWF AND 12Z GFS KEEP THE LOW CENTER IN
SOUTHERN IL. ISENTROPIC SURFACES SHOW MODERATE UPGLIDE ACROSS THE
LOCAL AREA TONIGHT AND QPF FIELDS INDICATE LIGHT PRECIP
ACCUMULATIONS RESULTING SO FEEL A PERIOD OF TEMPO -SHRA WARRANTED
FOR MID EVE INTO LATE OVERNIGHT.
AREAS OF MVFR HAS SPREAD INTO NE AND N CENTRAL IL LATE MORNING-
EARLY AFTERNOON WITH AREAS OF IFR FURTHER TO THE W...MAINLY ACROSS
WESTERN AND SOUTHERN IA. MOISTURE PROGS INDICATE THAT THE LOWER
LEVELS MOISTEN UP BY EARLY THIS EVENING. WITH MOIST LOW LEVELS
FROM SHOWERS AND LIGHT LOW LEVEL FLOW OVERNIGHT ANTICIPATE
CEILINGS TO FALL TO IFR. DURING THE MID MORNING WED EXPECT
IMPROVEMENT TO MVFR AND EVENTUALLY VFR THOUGH TIMING NOT VERY
CERTAIN DUE TO THE VARYING HANDLING OF SURFACE FEATURES AND THEIR
INFLUENCE ON ON QUICKLY N AND NW LOW LEVEL FLOW GETS ESTABLISHED
ACROSS THE REGION.
TRS
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE ALL ELEMENTS EARLY AFTERNOON.
* MODERATE CONFIDENCE IN TIMING ONSET OF MVFR AND IFR CONDITIONS
LATE AFTERNOON AND TONIGHT.
* HIGH CONFIDENCE THAT IF ANY ISOLD TS DEVELOP THIS AFTERNOON
THEN WILL REMAIN S OF MDW AND ORD.
* LOW CONFIDENCE IN TIMING OF IMPROVEMENT TO MVFR THEN VFR DURING
WED MORNING.
TRS
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
* WEDNESDAY NIGHT...CHANCE OF TSRA.
* THURSDAY...DRY/VFR.
* FRIDAY...CHANCE OF TSRA.
* SATURDAY AND SUNDAY...DRY/VFR.
* MONDAY...CHANCE OF TSRA.
&&
.MARINE...
305 AM...BROAD HIGH PRESSURE OVER THE LAKES REGION AND EXTENDING
INTO THE MID ATLANTIC WILL SLOWLY MOVE EAST TODAY AND TONIGHT AS
LOW PRESSURE OF NORTHERN MANITOBA MOVES EAST TO NEAR JAMES BAY BY
THURSDAY MORNING. SOUTHERLY WINDS WILL CONTINUE INTO WEDNESDAY
AFTERNOON WHEN A TRAILING COLD FRONT FROM THE LOW MOVES ACROSS THE
LAKE SHIFTING WINDS NORTHWEST. AS HIGH PRESSURE MOVES FROM THE
NORTHERN PLAINS WEDNESDAY NIGHT TO THE OHIO VALLEY THURSDAY
NIGHT...THE GRADIENT TIGHTENS SOME WEDNESDAY NIGHT INTO THURSDAY
MORNING ACROSS THE SOUTHERN HALF OR SO OF THE LAKE AND WHILE A
PERIOD OF 15-20 KTS LOOKS POSSIBLE...COULD BE SOME HIGHER GUSTS
INTO THE MID 20KT RANGE TOWARD THURSDAY MORNING. SPEEDS DIMINISH
THURSDAY NIGHT BUT WINDS REMAIN GENERALLY WESTERLY UNTIL ANOTHER
COLD FRONT MOVES ACROSS THE LAKES REGION FRIDAY AND FRIDAY NIGHT.
CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1142 AM CDT TUE JUL 30 2013
.DISCUSSION...
931 AM CDT
UPDATED MORNING POP/WEATHER GRIDS TO ACCOUNT FOR CURRENT RADAR
TRENDS AND ALSO BOOSTED POPS THIS AFTERNOON...MAINLY FOR SOUTH AND
SOUTHWEST PORTIONS OF THE AREA. FORECAST SOUNDINGS FROM ORD ARE
STILL SHOWING CONSIDERABLE DRY AIR AROUND 800MB FOR THE METRO
AREA...BUT OBVIOUSLY THE AIR IS FAIRLY WELL SATURATED FARTHER TO
THE SOUTHWEST. THE CURRENT TRENDS ARE DEPICTED NICELY BY MOISTURE
CONVERGENCE FIELDS IN THE RAP MODEL...SO HAVE LEANED TOWARD THAT
EVOLUTION FOR THE REST OF THE DAY. MAY NEED FURTHER UPDATES IF
ACTIVITY SHOWS GOOD SIGNS OF HOLDING TOGETHER LATER INTO THE
AFTERNOON. GIVEN EXISTING AND FORECAST CAPE TRENDS AND SOUNDING
PROFILES...MAY ALSO NEED TO ADD MENTION OF THUNDERSTORMS LATER
TODAY...BUT MID LEVEL LAPSE RATES ARE ONLY MARGINALLY FAVORABLE.
LENNING
//PREV DISCUSSION...
323 AM CDT
TODAY...
SFC RIDGING CONTINUES TO BE AN INFLUENCE ON THE REGION...DESPITE
DRIFTING EAST OF THE CWFA AND BECOMING CENTERED OVER THE EASTERN
OHIO VALLEY THIS MORNING. IR IMAGERY DEPICTS A COMPLEX OF
THUNDERSTORMS ACROSS THE SOUTHERN PLAINS...WITH REGIONAL RADAR
SHOWING PRECIP RETURNS LIFTING INTO NORTHEAST MISSOURI/SOUTHEAST
IOWA. FOR MUCH OF THE DAY TODAY EXPECT SFC RIDGING TO CONTINUE TO
KEEP PRECIP WEST/SOUTHWEST OF THE CWFA. GUIDANCE HOLDS ONTO THE
SOUTHEAST FLOW AT THE SFC...WITH SOUNDINGS SUGGESTING CONSIDERABLE
DRY AIR THRU 15Z THEN SLOWLY MOISTENING FROM THE TOP DOWN. PWAT
VALUES SLOWLY INCREASE...HOVERING ARND 1.8" BY LATE THIS AFTN/EVE.
BY 18Z EXPECT SCATTERED PRECIP TO BEGIN PUSHING OVER THE CWFA. BASED
ON THE SOUNDINGS CONVECTIVE POTENTIAL REMAINS VERY LOW...EXCEPT FOR
FAR SOUTHERN AREAS OF THE CWFA. OTHERWISE EXPECT PRECIP TO REMAIN
LIGHT IN INTENSITY AND MINIMAL COVERAGE.
WITH GRADUAL THICKENING OF THE CLOUD SHIELD...TEMPS WILL INITIALLY
WARM THEN THE RATE OF CLIMB WILL BEGIN TO SLOW GIVEN THE INCREASED
MOISTURE IN THE ATMOSPHERE. STILL THINK THAT TEMPS WILL WARM TO THE
MID 70S...HOWEVER IF CLOUDS CAN THICKEN FASTER THIS MORNING TEMPS
MAY STRUGGLE TO WARM BEYOND THE LOW 70S.
CONFIDENCE...MEDIUM.
TONIGHT THROUGH WEDNESDAY...
WEAK SHORTWAVE CONTINUES TO LIFT NORTHEAST ACROSS MISSOURI LATE THIS
AFTN/EARLY EVE...WHILE ANTI-CYCLONIC FLOW OVER THE OHIO VALLEY
CONTINUES TO PROVIDE A DRY INFLUENCE ON THE NEAR SFC ENVIRONMENT
ACROSS NORTHERN IL/NORTHWEST IN. SFC WINDS APPEAR TO HOLD FROM THE
SOUTHEAST...AND UNDER A LIGHT GRADIENT WILL LIKELY BE LESS THAN 10
MPH. THIS COULD BE JUST ENOUGH OF A DRY FLOW IN THE LLVLS TO HOLD
FULL SATURATION OF THE PROFILE. GUIDANCE DOES INDICATE A SLOW
MOISTENING OF THE LOW/MID LVLS AFT 21Z THIS AFTN...WITH PWAT VALUES
STEADILY INCREASING TO ARND 1.5-1.8". THE TREND HAS BEEN DRIER AND
FURTHER SOUTH WITH THIS SYSTEM...HOWEVER JUST ENOUGH MOISTURE COULD
LIFT OVERHEAD AND WITH SOME OMEGA OR LIFT PRESENT...SPRINKLES/LIGHT
SHRA COULD DEVELOP LATE THIS EVENING/OVERNIGHT. LOCAL HI-RES WRF
SOLUTION KEEPS ALL PRECIP TO THE SOUTH OF A PONTIAC TO FOWLER LINE.
HAVE TRIMMED BACK ON POPS TO THE HIGH TEENS...AND EXPECT COVERAGE TO
BE MINIMAL WITH PRECIP TONIGHT. IN ADDITION DROPLET SIZE WILL BE
SMALL AS WELL...WHICH COULD TRANSLATE INTO DRIZZLE OR CHANGING
PRECIP TO SPRINKLES INSTEAD OF SHOWERS.
WITH A 500MB WAVE RATHER FLAT...THIS SYSTEM WILL REMAIN PROGRESSIVE
AND PUSH TO THE EAST BY WED MORNING. ALONG THE BACK EDGE OF THE
DEPARTING WEAK SFC WAVE IT APPEARS SOME DIFLUENT FLOW TRIES TO
DEVELOP AND COULD BRING A BRIEF END TO THE PRECIP BY DAYBREAK WED.
THEN THE FOCUS TURNS TOWARDS AN ADVANCING FRONTAL BOUNDARY THAT WILL
BE SLIDING INTO THE UPPER MIDWEST EARLY WED.
LLVL FLOW WILL BECOME SOUTHERLY TO SOUTHWESTERLY AHEAD OF THE COLD
FRONT...WITH MARGINAL INSTABILITY DEVELOPING IN THE AFTN HOURS WED.
WITH THE LACK OF STRONG SHEAR AND MODEL SOUNDINGS INDICATING SOME
DRY AIR IN THE NEAR SFC...IT IS CONCEIVABLE THAT MUCH OF WED COULD
BE DRY. AS PREVIOUSLY NOTED IN REGARDS TO THE LCL HI-RES WRF...THIS
SOLUTION CONTINUES THE DRY THEME FOR WED. AT THIS POINT HAVE ONLY
TRIMMED BACK ON POPS FOR WED...AND FOCUSED THE TIMING TOWARDS THE
AFTN/EVE HOURS OR CLOSER TO FROPA. 500MB TROUGH AXIS APPEARS TO PUSH
INTO THE WESTERN GREAT LAKES ARND 00Z THUR...WITH DIMINISHING LLVL
MOISTURE. MID-LVL SHEAR WILL INCREASE AS THE BNDRY NEARS...AND WITH
MARGINAL INSTABILITY COULD ALLOW SOME ISOLATED THUNDERSTORMS TO
DEVELOP LATE WED AFTN.
IN REGARDS TO TEMPS TONIGHT...EXPECT CONSIDERABLE CLOUD COVER TO
HOLD TEMPS SLIGHTLY WARMER OR IN THE MID 60S AWAY FROM LAKE MICHIGAN
AND UPR 60S CLOSER TO THE LAKE. THEN FOR WED TEMPS WILL BE SLIGHTLY
WARMER AND CLOSER TO 80 DEG. IF THE SOUTH/SOUTHWEST FLOW IS SLIGHTLY
STRONGER WED IN ADVANCE OF THE FRONT...TEMPS MAY BE ABLE TO WARM
FURTHER OR 80-83 DEG.
CONFIDENCE...MEDIUM.
CONFIDENCE IN PRECIP...LOW.
THURSDAY THROUGH FRIDAY...
500MB TROUGH QUICKLY SLIDES OVERHEAD WITH ANTI-CYCLONIC FLOW
BUILDING INTO THE REGION FROM THE WEST. THIS WILL AID IN PROVIDING
DRY WEATHER FOR THUR/THUR NIGHT. SFC RIDGE PUSHES FURTHER SOUTH
ACROSS THE TENN VALLEY FRI...WHILE A LOBE OF VORTICITY IS PROGGED TO
SLIDE SOUTHEAST ACROSS THE WESTERN GREAT LAKES FRI. THIS APPEARS TO
BE ASSOCIATED WITH A FRONTAL BOUNDARY...WHICH MAY HAVE SOME PRECIP
ACCOMPANYING FROPA FRI/FRI EVE. ALTHOUGH THE SETUP LOOKS MORE
FAVORABLE FOR A DRY FROPA AS ANTI-CYCLONIC FLOW WILL BE DEPARTING
WITH YET ANOTHER ANTI-CYCLONIC FLOW SLIDING SOUTHEAST ACROSS THE
NORTHERN PLAINS/UPPER MIDWEST FRI NIGHT.
TEMPS CONTINUE TO BE UNSEASONABLY COOL...WITH AFTN HIGHS STRUGGLING
TO WARM BEYOND THE UPR 70S IN MANY LOCATIONS. A FEW SITES MAY TOUCH
80 DEG FRI AFTN.
CONFIDENCE...MEDIUM.
SATURDAY THROUGH MONDAY...
EXTENDED PERIODS CONTINUE TO FEATURE A COOL NORTHWEST SETUP WITH
ENSEMBLES DEMONSTRATING MINIMAL NOISE OR DIFFERENCES. THE STRENGTH
OF THE DOWNSTREAM RIDGE OVER THE CANADIAN MARITIME DOES EXHIBIT SOME
WEAKENING SUN...WHICH SHOULD ALLOW THE GREAT LAKES TROUGH TO WEAKEN
AND PUSH EAST. HOWEVER PROGRESSING TOWARDS THE FINAL FEW
PERIODS...HIGH LATITUDE RIDGING IS PROGGED TO DEVELOP OVER THE NORTH
ATLANTIC AND STRETCH WEST ACROSS WESTERN CANADA. IF THIS SOLUTION
VERIFIES...FLOW ACROSS THE GREAT LAKES REGION WILL LIKELY REMAIN IN
A UNSEASONABLY COOL SETUP.
OPERATIONAL SOLUTIONS HAVE SFC RIDGING BUILDING IN FOR SAT AND
LINGERING THRU SUN NGT...WHICH WILL PROVIDE DRY WEATHER. THEN THE
500MB FLOW BEGINS TO FLATTEN AND BECOME MORE FLUID...WITH A FRONTAL
BOUNDARY AND A WEAK SYSTEM APPROACHING THE REGION TOWARDS THE FINAL
PERIODS WITH A CHANCE OF PRECIP FOR EARLY NEXT WEEK.
CONFIDENCE...MEDIUM/HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* CHANCE OF LIGHT SHOWERS LATE MORNING THROUGH AFTERNOON...BETTER
CHANCE THIS MID EVENING INTO LATE TONIGHT.
* POTENTIAL FOR IFR CIGS MID EVENING INTO WED MORNING.
TRS
//DISCUSSION...UPDATED 12Z...
AN AREA OF SHOWERS/RAIN OVER WESTERN IL CONTINUES TO SPREAD NORTH
AND NORTHEAST THIS MORNING AND IS SLOWLY ERODING ON THE NORTHERN
EDGE AS IT ENCOUNTERS DRIER AIR. SHORT TERM/HI RES GUIDANCE IS IN
FAIR AGREEMENT THAT THIS ERODING TREND WILL CONTINUE THIS MORNING.
BUT DO EXPECT THIS ACTIVITY TO REACH A RFD/DKB/ARR LINE...AT LEAST
IN THE FORM OF SPRINKLES. ADDITIONAL SHOWERS MAY DEVELOP LATER
THIS AFTERNOON AND CONTINUE INTO THIS EVENING BUT CONFIDENCE
REGARDING COVERAGE IS FAIRLY LOW AND INCLUDED VICINITY MENTION BUT
STILL EXPECT MANY DRY HOURS.
WINDS WILL REMAIN SOUTHEASTERLY INTO THIS EVENING WITH SPEEDS
INCREASING INTO THE 7-10KT RANGE. ITS POSSIBLE A MORE TRADITIONAL
LAKE BREEZE MAY DEVELOP THIS AFTERNOON...ESPECIALLY FROM CHICAGO
NORTH INTO LAKE COUNTY IL. HOW FAR INLAND IT MOVES IS UNCERTAIN
AND TRENDS WILL NEED TO BE MONITORED INTO THIS AFTERNOON. SPEEDS
WILL DIMINISH THIS EVENING WITH LIGHT AND VARIABLE OR CALM WINDS
EXPECTED TONIGHT.
THE LOW LEVELS CONTINUE TO MOISTEN THROUGH THE EVENING AND INTO
THE OVERNIGHT HOURS. THERE IS A FAIRLY EXTENSIVE AREA OF LIFR/IFR
CIGS ACROSS THE CENTRAL PLAINS AND SOME OF THIS WILL LIKELY SHIFT
EAST TONIGHT. MOST CONFIDENT OF THIS REACHING RFD BUT FOR THE REST
OF THE TAFS...HAVE JUST INCLUDED SCATTERED IFR MENTION FOR NOW. CMS
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH FOR -RA/-SHRA ACROSS LOCAL AREA LATE MORNING THOUGH
AFTERNOON.
* HIGH FOR ADDITIONAL -RA/-SHRA MID EVENING INTO OVERNIGHT.
* HIGH FOR MVFR CIGS AND VSBYS DEVELOPING THIS EVE AD PERSISTING
OVERNIGHT...MODERATE FOR LOWERING TO IFR CIGS.
TRS
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
* WEDNESDAY NIGHT...CHANCE OF TSRA.
* THURSDAY...DRY/VFR.
* FRIDAY...CHANCE OF TSRA.
* SATURDAY AND SUNDAY...DRY/VFR.
* MONDAY...CHANCE OF TSRA.
&&
.MARINE...
305 AM...BROAD HIGH PRESSURE OVER THE LAKES REGION AND EXTENDING
INTO THE MID ATLANTIC WILL SLOWLY MOVE EAST TODAY AND TONIGHT AS
LOW PRESSURE OF NORTHERN MANITOBA MOVES EAST TO NEAR JAMES BAY BY
THURSDAY MORNING. SOUTHERLY WINDS WILL CONTINUE INTO WEDNESDAY
AFTERNOON WHEN A TRAILING COLD FRONT FROM THE LOW MOVES ACROSS THE
LAKE SHIFTING WINDS NORTHWEST. AS HIGH PRESSURE MOVES FROM THE
NORTHERN PLAINS WEDNESDAY NIGHT TO THE OHIO VALLEY THURSDAY
NIGHT...THE GRADIENT TIGHTENS SOME WEDNESDAY NIGHT INTO THURSDAY
MORNING ACROSS THE SOUTHERN HALF OR SO OF THE LAKE AND WHILE A
PERIOD OF 15-20 KTS LOOKS POSSIBLE...COULD BE SOME HIGHER GUSTS
INTO THE MID 20KT RANGE TOWARD THURSDAY MORNING. SPEEDS DIMINISH
THURSDAY NIGHT BUT WINDS REMAIN GENERALLY WESTERLY UNTIL ANOTHER
COLD FRONT MOVES ACROSS THE LAKES REGION FRIDAY AND FRIDAY NIGHT.
CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION...CORRECTED
NWS DODGE CITY KS
458 PM CDT TUE JUL 30 2013
...CORRECTED LONG TERM SECTION...
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 156 PM CDT TUE JUL 30 2013
TODAY IS SEEING A VERY SLOW CLEARING PATTERN IN THE CLOUDS FROM
WEST TO EAST. THIS SLOWNESS IN CLEARING IS PARTIALLY DUE TO THE
NORTH TO NORTHEAST LOW LEVEL FLOW, WHICH IS A SLIGHT UPSLOPE
PATTERN. THE OTHER REASON THE EAST IS SO SLOW TO CLEAR OUT IS THE
ABUNDANT SURFACE MOISTURE ACROSS OUR EASTERN ZONES, WITH PLENTY OF
LEFTOVER RAINFALL STILL ACROSS MUCH OF THE EASTERN FORECAST AREA,
ESPECIALLY SOUTHEAST OF A LINE FROM LA CROSSE TO ASHLAND. SOME OF
THESE COUNTIES RECEIVED OVER 3 INCHES OF RAINFALL MONDAY EVENING,
ESPECIALLY ACROSS PRATT AND BARBER COUNTIES. FOR THIS REASON, ALONG
WITH EXPECTED CLEAR SKIES AND LIGHT WINDS EXPECTED, THERE SHOULD
BE SOME MORE FOG FORM TOWARD 09Z TO 10Z. I HAVE DECIDED TO PUT IN
PATCHY FOG WORDING FOR NOW ACROSS OUR SOUTHEASTERN SECTIONS, AND
LATER SHIFTS CAN UPDATE TO DENSE FOG IF IT FORMS. BOTH THE NAM
AND THE HRRR MODELS ARE INDICATED AROUND 1SM VISIBILITIES IN FOG.
AS FOR LOW TEMPERATURES, NO CHANGES WERE MADE TO THE PREVIOUS
FORECAST. CLEAR SKIES AND LIGHT WINDS WILL ALLOW TEMPERATURES TO
DROP TO THE MID 60S IN OUR WEST AND THE UPPER 60S IN OUR
SOUTHEAST.
MOSTLY SUNNY SKIES AREA EXPECTED WEDNESDAY, AFTER SOME SCATTERED
MORNING FOG. WINDS WILL BE LIGHT AND VARIABLE EARLY, THEN SHIFT TO
THE SOUTHEAST IN THE AFTERNOON AT 10 TO 20 MPH. A COLD FRONT
WILL APPROACH WESTERN KANSAS BY AFTERNOON. THE NAM MODEL BRINGS IN
THUNDERSTORMS WEDNESDAY AFTERNOON AS EARLY AS 19Z IN OUR NORTHWEST
ZONES OF SCOTT AND LANE COUNTIES, AND ADVANCES THE RAIN TOWARD
DODGE CITY AS EARLY AS 22Z. THE ECMWF AND GFS MODELS ARE A LITTLE
SLOWER, BRINGING RAIN TO SCOTT AND LANE COUNTIES AFTER 22Z AND NOT
NEAR DODGE CITY UNTIL AFTER 02Z. HAVE STARTED SLIGHT 20 PERCENT
CHANCES IN OUR FAR NORTHWEST, SUCH AS SCOTT AND LANE COUNTIES, AND
DELAYED THE ONSET OF CHANCE POP CATEGORIES IN THE DODGE CITY AREA
UNTIL 03Z. SOME OF THE LATE AFTERNOON AND EVENING STORMS COULD
CONTAIN DAMAGING WINDS AND HAIL AS LARGE AS GOLFBALLS. THE FRONT
WILL MOVE THROUGH WESTERN AND INTO CENTRAL KANSAS BY WEDNESDAY
EVENING, BRINGING RAIN CHANCES FOR SHOWERS AND THUNDERSTORMS TO
THE PRATT AND COLDWATER AREAS AFTER 00Z THURSDAY. WITH SKIES
STARTING OUT WEDNESDAY MORNING AS MOSTLY SUNNY, THEN BECOMING
PARTLY CLOUDY BY MID TO LATE AFTERNOON, AND POSSIBLY EVEN MOSTLY
CLOUDY BY EVENING, MAXIMUM TEMPERATURES COULD BE A LITTLE TRICKY.
STAYED WITH THE PREVIOUS FORECAST OF MID 90S IN THE WEST AND NEAR
90F IN THE EAST. HOW MUCH RAIN WILL FALL IS ALWAYS A LITTLE
CHALLENGING, BUT I THINK THE QPF_FM_POP PROCEDURE DID A FAIRLY
GOOD JOB WITH FORECAST RAINFALL.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 339 PM CDT TUE JUL 30 2013
AN UPPER LEVEL LONGWAVE TROUGH WILL GENERALLY RESIDE OVER THE EASTERN
UNITED STATES THROUGH TUESDAY AUGUST 6TH, WITH UPPER LEVEL RIDGING
WAFFLING BACK AND FORTH BETWEEN NEW MEXICO AND TEXAS. ALONG THE
NORTHERN PERIPHERY OF THE RIDGE OVER THE CENTRAL HIGH PLAINS, A
QUASI-STATIONARY SURFACE FRONTAL BOUNDARY WILL EXIST, WITH LOW
LEVEL MOISTURE CONVERGING ALONG AND NORTH OF THE BOUNDARY.
ADDITIONALLY, EVAPOTRANSPIRATION FROM THE PREVIOUS HEAVY RAINS
ACROSS THE SOUTHERN AND CENTRAL PLAINS AND SUBSEQUENT TRANSPORT OF
THIS MOISTURE TO THE NORTHWEST WITH THE LOW LEVEL FLOW, WILL
ENHANCE MIXING RATIOS EVEN FURTHER. CONVECTIVE CLUSTERS WILL
ORIGINATE OFF OF THE VARIOUS TERRAIN FEATURES IN THE LEE OF THE
ROCKIES JUST ABOUT EVERY DAY, AND A FEW OF THESE COULD GROW
UPSCALE INTO LARGER CONVECTIVE CLUSTERS AND AFFECT WESTERN KANSAS
THROUGH AUGUST 6TH. THE TIMING OF THE INDIVIDUAL STORM CLUSTERS
CANNOT BE PREDICTED WITH MUCH ACCURACY IN THIS REGIME. THEREFORE,
20 TO 40% STORM CHANCES WERE GENERALLY MAINTAINED THROUGH AUGUST
6TH. ALSO, GIVEN THE UNCERTAINTY IN ANY CONVECTION AND RESULTANT
COOL OUTFLOW, HIGH TEMPERATURES WILL BE TRICKY AS WELL. OUR BEST
ESTIMATE IS THAT HIGH AND LOW TEMPERATURES WILL BE WITHIN A FEW
DEGREES OF CLIMATOLOGICAL VALUES (HIGHS 86-97F AT DODGE CITY, WITH
COOLER READINGS THAN THIS NEAR INTERSTATE 70 AND WARMER READINGS
NEAR THE OKLAHOMA STATE LINE). KEEP IN MIND THAT ANY WIDESPREAD
CLOUD COVER OR RAINFALL COULD LEAD TO MUCH COOLER TEMPERATURES ON
ANY GIVEN DAY.
AFTER AUGUST 6TH, THE VARIOUS MODELS ARE ADVERTISING A STRONG UPPER
LEVEL LOW TO DROP SOUTHWARD OUT OF CANADA INTO THE GREAT LAKES
REGION. THE ASSOCIATED COLD FRONT COULD BRING MUCH COOLER AIR INTO THE
CENTRAL PLAINS BY LATE NEXT WEEK, WITH HIGHS POSSIBLY FALLING INTO
THE 70S DEPENDING ON THE AMOUNT OF ACCOMPANYING CLOUD COVER AND
PRECIPITATION BEHIND THE FRONT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1145 AM CDT TUE JUL 30 2013
IN THE NEAR TERM, EXPECT MVFR CIGS AND GOOD VSBYS. WINDS WILL BE
FROM THE NORTHEAST TODAY IN THE 8 KNOT RANGE. SKIES WILL CLEAR
FROM WEST TO EAST GRADUALLY, BECOMING SCATTERED AT 250 THIS
EVENING. LIGHT WINDS AND ABUNDANT LOW LEVEL MOISTURE WILL LEAD TO
SOME FOG DEVELOPING AFTER 09Z. FOR NOW, I AM EXPECTING SOME 2SM
IFR FOG POSSIBLE, WITH A CHANCE FOR ISOLATED VSBYS LESS THAN 1
MILE IN FOG.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 66 93 68 93 / 10 20 30 30
GCK 66 94 68 94 / 20 30 40 30
EHA 67 95 67 95 / 20 30 40 30
LBL 68 95 69 95 / 20 30 40 30
HYS 65 89 68 92 / 10 30 30 40
P28 69 89 70 94 / 10 10 10 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURKE
LONG TERM...FINCH
AVIATION...BURKE
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
353 PM CDT TUE JUL 30 2013
...UPDATED FOR LONG TERM DISCUSSION...
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 156 PM CDT TUE JUL 30 2013
TODAY IS SEEING A VERY SLOW CLEARING PATTERN IN THE CLOUDS FROM
WEST TO EAST. THIS SLOWNESS IN CLEARING IS PARTIALLY DUE TO THE
NORTH TO NORTHEAST LOW LEVEL FLOW, WHICH IS A SLIGHT UPSLOPE
PATTERN. THE OTHER REASON THE EAST IS SO SLOW TO CLEAR OUT IS THE
ABUNDANT SURFACE MOISTURE ACROSS OUR EASTERN ZONES, WITH PLENTY OF
LEFTOVER RAINFALL STILL ACROSS MUCH OF THE EASTERN FORECAST AREA,
ESPECIALLY SOUTHEAST OF A LINE FROM LA CROSSE TO ASHLAND. SOME OF
THESE COUNTIES RECEIVED OVER 3 INCHES OF RAINFALL MONDAY EVENING,
ESPECIALLY ACROSS PRATT AND BARBER COUNTIES. FOR THIS REASON, ALONG
WITH EXPECTED CLEAR SKIES AND LIGHT WINDS EXPECTED, THERE SHOULD
BE SOME MORE FOG FORM TOWARD 09Z TO 10Z. I HAVE DECIDED TO PUT IN
PATCHY FOG WORDING FOR NOW ACROSS OUR SOUTHEASTERN SECTIONS, AND
LATER SHIFTS CAN UPDATE TO DENSE FOG IF IT FORMS. BOTH THE NAM
AND THE HRRR MODELS ARE INDICATED AROUND 1SM VISIBILITIES IN FOG.
AS FOR LOW TEMPERATURES, NO CHANGES WERE MADE TO THE PREVIOUS
FORECAST. CLEAR SKIES AND LIGHT WINDS WILL ALLOW TEMPERATURES TO
DROP TO THE MID 60S IN OUR WEST AND THE UPPER 60S IN OUR
SOUTHEAST.
MOSTLY SUNNY SKIES AREA EXPECTED WEDNESDAY, AFTER SOME SCATTERED
MORNING FOG. WINDS WILL BE LIGHT AND VARIABLE EARLY, THEN SHIFT TO
THE SOUTHEAST IN THE AFTERNOON AT 10 TO 20 MPH. A COLD FRONT
WILL APPROACH WESTERN KANSAS BY AFTERNOON. THE NAM MODEL BRINGS IN
THUNDERSTORMS WEDNESDAY AFTERNOON AS EARLY AS 19Z IN OUR NORTHWEST
ZONES OF SCOTT AND LANE COUNTIES, AND ADVANCES THE RAIN TOWARD
DODGE CITY AS EARLY AS 22Z. THE ECMWF AND GFS MODELS ARE A LITTLE
SLOWER, BRINGING RAIN TO SCOTT AND LANE COUNTIES AFTER 22Z AND NOT
NEAR DODGE CITY UNTIL AFTER 02Z. HAVE STARTED SLIGHT 20 PERCENT
CHANCES IN OUR FAR NORTHWEST, SUCH AS SCOTT AND LANE COUNTIES, AND
DELAYED THE ONSET OF CHANCE POP CATEGORIES IN THE DODGE CITY AREA
UNTIL 03Z. SOME OF THE LATE AFTERNOON AND EVENING STORMS COULD
CONTAIN DAMAGING WINDS AND HAIL AS LARGE AS GOLFBALLS. THE FRONT
WILL MOVE THROUGH WESTERN AND INTO CENTRAL KANSAS BY WEDNESDAY
EVENING, BRINGING RAIN CHANCES FOR SHOWERS AND THUNDERSTORMS TO
THE PRATT AND COLDWATER AREAS AFTER 00Z THURSDAY. WITH SKIES
STARTING OUT WEDNESDAY MORNING AS MOSTLY SUNNY, THEN BECOMING
PARTLY CLOUDY BY MID TO LATE AFTERNOON, AND POSSIBLY EVEN MOSTLY
CLOUDY BY EVENING, MAXIMUM TEMPERATURES COULD BE A LITTLE TRICKY.
STAYED WITH THE PREVIOUS FORECAST OF MID 90S IN THE WEST AND NEAR
90F IN THE EAST. HOW MUCH RAIN WILL FALL IS ALWAYS A LITTLE
CHALLENGING, BUT I THINK THE QPF_FM_POP PROCEDURE DID A FAIRLY
GOOD JOB WITH FORECAST RAINFALL.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 339 PM CDT TUE JUL 30 2013
AN UPPER LEVEL LONGWAVE TROUGH WILL GENERALLY RESIDE OVER THE EASTERN
UNITED STATES THROUGH WEDNESDAY JULY 6TH, WITH UPPER LEVEL RIDGING
WAFFLING BACK AND FORTH BETWEEN NEW MEXICO AND TEXAS. ALONG THE
NORTHERN PERIPHERY OF THE RIDGE OVER THE CENTRAL HIGH PLAINS, A
QUASI-STATIONARY SURFACE FRONTAL BOUNDARY WILL EXIST, WITH LOW
LEVEL MOISTURE CONVERGING ALONG AND NORTH OF THE BOUNDARY.
ADDITIONALLY, EVAPOTRANSPIRATION FROM THE PREVIOUS HEAVY RAINS
ACROSS THE SOUTHERN AND CENTRAL PLAINS AND SUBSEQUENT TRANSPORT OF
THIS MOISTURE TO THE NORTHWEST WITH THE LOW LEVEL FLOW, WILL
ENHANCE MIXING RATIOS EVEN FURTHER. CONVECTIVE CLUSTERS WILL
ORIGINATE OFF OF THE VARIOUS TERRAIN FEATURES IN THE LEE OF THE
ROCKIES JUST ABOUT EVERY DAY, AND A FEW OF THESE COULD GROW UPSCALE
INTO LARGER CONVECTIVE CLUSTERS AND AFFECT WESTERN KANSAS THROUGH
JULY 6TH. THE TIMING OF THE INDIVIDUAL STORM CLUSTERS CANNOT BE
PREDICTED WITH MUCH ACCURACY IN THIS REGIME. THEREFORE, 20 TO 40%
STORM CHANCES WERE GENERALLY MAINTAINED THROUGH JULY 6TH. ALSO,
GIVEN THE UNCERTAINTY IN ANY CONVECTION AND RESULTANT COOL
OUTFLOW, HIGH TEMPERATURES WILL BE TRICKY AS WELL. OUR BEST
ESTIMATE IS THAT HIGH AND LOW TEMPERATURES WILL BE WITHIN A FEW
DEGREES OF CLIMATOLOGICAL VALUES (HIGHS 86-97F AT DODGE CITY, WITH
COOLER READINGS THAN THIS NEAR INTERSTATE 70 AND WARMER READINGS
NEAR THE OKLAHOMA STATE LINE). KEEP IN MIND THAT ANY WIDESPREAD
CLOUD COVER OR RAINFALL COULD LEAD TO MUCH COOLER TEMPERATURES
ON ANY GIVEN DAY.
AFTER JULY 6TH, THE VARIOUS MODELS ARE ADVERTISING A STRONG UPPER
LEVEL LOW TO DROP SOUTHWARD OUT OF CANADA INTO THE GREAT LAKES
REGION. THE ASSOCIATED COLD FRONT COULD BRING MUCH COOLER AIR INTO THE
CENTRAL PLAINS BY LATE NEXT WEEK, WITH HIGHS POSSIBLY FALLING INTO
THE 70S DEPENDING ON THE AMOUNT OF ACCOMPANYING CLOUD COVER AND
PRECIPITATION BEHIND THE FRONT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1145 AM CDT TUE JUL 30 2013
IN THE NEAR TERM, EXPECT MVFR CIGS AND GOOD VSBYS. WINDS WILL BE
FROM THE NORTHEAST TODAY IN THE 8 KNOT RANGE. SKIES WILL CLEAR
FROM WEST TO EAST GRADUALLY, BECOMING SCATTERED AT 250 THIS
EVENING. LIGHT WINDS AND ABUNDANT LOW LEVEL MOISTURE WILL LEAD TO
SOME FOG DEVELOPING AFTER 09Z. FOR NOW, I AM EXPECTING SOME 2SM
IFR FOG POSSIBLE, WITH A CHANCE FOR ISOLATED VSBYS LESS THAN 1
MILE IN FOG.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 66 93 68 93 / 10 20 30 30
GCK 66 94 68 94 / 20 30 40 30
EHA 67 95 67 95 / 20 30 40 30
LBL 68 95 69 95 / 20 30 40 30
HYS 65 89 68 92 / 10 30 30 40
P28 69 89 70 94 / 10 10 10 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURKE
LONG TERM...FINCH
AVIATION...BURKE
AREA FORECAST DISCUSSION
NWS GOODLAND KS
253 PM MDT TUE JUL 30 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 250 PM MDT TUE JUL 30 2013
LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOWS ELONGATED RIDGE ACROSS
THE SOUTHERN PLAINS WITH WESTERLY FLOW IN PLACE ACROSS THE
CENTRAL/HIGH PLAINS. A WEAK LEE TROUGH IS CURRENTLY IN PLACE ACROSS
EASTERN COLORADO WITH A WEAK CONVERGENCE REGION EXTENDING INTO OUR
WESTERN CWA.
THIS WILL ACT AS THE FOCUS FOR ISOLATED THUNDERSTORM DEVELOPMENT
THIS AFTERNOON...WITH CU FIELD ALREADY IN PLACE AND RADAR INDICATING
SEVERAL DEVELOPING UPDRAFTS JUST NW OF OUR CWA NEAR YUMA COUNTY. WITH
STORM MOTIONS OUT OF THE EAST 10-20KT MOST STORMS WILL BE SLOW
MOVERS...THOUGH WE COULD STILL SEE THIS ACTIVITY MOVE FURTHER EAST
IN OUR CWA THROUGH THE AFTERNOON BEFORE FALLING APART AFTER SUNSET
WITH LOSS OF DAYTIME HEATING AND INCREASING LOW LEVEL CINH. LATEST
RAP ANALYSIS SHOWS SB/ML CAPE VALUES RANGING FROM 1000-1500
J/KG...AND WITH ADJUSTED SOUNDINGS SUPPORTING POSSIBLE CAPE VALUES
IN THE 2000-2500J/KG RANGE LATER THIS AFTERNOON. WITH HIGH TD
DEPRESSIONS TO ABOUT 700MB THROUGH A DRY ADIABATIC AIRMASS AND HIGH
LFC/LCL IN THE 10-13KFT RANGE WE COULD SEE STRONG THUNDERSTORM GUST
POTENTIAL. IF WE REALIZE THE HIGHER CAPE VALUES I COULDNT RULE OUT
LARGE HAIL POTENTIAL...HOWEVER AT THIS POINT STRONG WINDS ARE
PROBABLY THE GREATER THREAT WITH ANY THUNDERSTORMS THAT DEVELOP.
MET/MAV GUIDANCE ARE INDICATING FOG DEVELOPMENT TONIGHT...HOWEVER
WITH W-SW WINDS TO 10KT AT THE SURFACE AND BL WINDS IN EXCESS OF
20KT...I AM NOT AS CONFIDENT WE WILL SEE A REPEAT OF LAST NIGHT.
WITH TROUGH AXIS SHIFTING EAST WE COULD STILL SEE LIGHT SURFACE
WINDS IN THE EAST WHERE FOG WOULD BE MORE LIKELY TO OCCUR...AND
WHERE I KEPT PATCHY FOG MENTION.
A WEAK COLD FRONT WILL DROP SOUTH LATE TONIGHT AND STALL ALONG THE
NE/KS STATE LINE BY MIDDAY WEDNESDAY WITH A PRE FRONTAL TROUGH
SETTLING TO OUR SOUTHEAST. AHEAD OF THE TROUGH AXIS CAPE VALUES IN
EXCESS OF 2500 J/KG ARE ADVERTISED. THIS TROUGH AXIS WILL BE THE
MAIN FOCUS WITH GOOD SURFACE CONVERGENCE IN PLACE...AND I KEPT 30/40
POPS TIED TO THIS FEATURE...AND LOWER POPS TO THE NORTH. WITH BETTER
CAPE AND MARGINALLY BETTER SHEER WE WILL SEE A CHANCE FOR
THUNDERSTORMS TO BECOME BETTER ORGANIZED WITH SEVERE WIND/HAIL A
POSSIBILITY IN OUR SOUTHEAST DURING THE AFTERNOON.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 250 PM MDT TUE JUL 30 2013
NO MAJOR CHANGES SEEN TO THE UPPER PATTERN ACROSS THE SOUTHERN AND
CENTRAL PLAINS DURING THIS PERIOD. UPPER HIGH NOW CENTERED OVER
NEW MEXICO AND WAFFLE BACK AND FORTH OVER TO WEST TEXAS AND BACK DURING
PERIOD. ALTHOUGH THE UPPER RIDGE IS FORECAST TO ASSERT ITSELF SLIGHTLY
NORTH OVER THE MOUNTAINS...A SERIES OF WEAK UPPER IMPULSES WILL
CONTINUE TO MOVE OVER THE TOP OF THE RIDGE KEEPING IT FAIRLY
FLAT OVERALL.
THIS MAKES IT DIFFICULT TO ASSESS TIMING OF PRECIPITATION. ALL
GUIDANCE IS SUGGESTING AN ACTIVE FLOW REGIME WILL CONTINUE WITH
SLIGHT CHANCE TO CHANCE POPS EVERY DAY. RIGHT NOW THE MOST ACTIVE
PERIODS FOR PRECIPITATION LOOK TO BE THURSDAY NIGHT AND AGAIN
SATURDAY NIGHT. TEMPERATURES WILL CONTINUE SEASONAL WITH HIGHS
MOSTLY IN THE UPPER 80S TO LOWER 90S AND LOWS IN THE 60S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1146 AM MDT TUE JUL 30 2013
VFR CONDITIONS SHOULD PERSIST THROUGH THIS EVENING AT BOTH KGLD
AND KMCK THROUGH THE VALID TAF PERIOD. WITH SURFACE TROUGH AXIS
NEAR BOTH TERMINALS WINDS WILL BE SOMEWHAT ERRATIC...THOUGH THEY
SHOULD REMAIN BELOW 12KT AT THE SURFACE GENERALLY OUT OF THE EAST-
SOUTHEAST. THUNDERSTORMS MAY DEVELOP THIS AFTERNOON AHEAD OF
TROUGH AXIS ALONG KS/CO STATE LINE...HOWEVER WITH COVERAGE
ISOLATED I DECIDED AGAINST MENTION AT EITHER TAF SITE.
FOG WILL ONCE AGAIN BE POSSIBLE TONIGHT AFTER 09Z WITH MOIST
SURFACE LAYER STILL IN PLACE. MET/MAV GUIDANCE SHOWING CONDITIONS
DROPPING TO IFR/LIFR...HOWEVER WITH BL WINDS INCREASING TONIGHT
(ESPECIALLY OVER KGLD) I AM SKEPTICAL OF CONDITIONS MUCH LOWER THAN
MVFR. AT THIS TIME IF WE SAW LOWER CONDITIONS I THINK IT WOULD BE
AT KMCK WHERE SURFACE WINDS MAY REMAIN VARIABLE ALONG REPUBLICAN
RIVER VALLEY. A W-SW DRAINAGE WIND AROUND 10KT MAY HELP KEEP
CONDITIONS VFR AT KGLD. ANY FOG SHOULD DISSIPATE BY 15Z AS DIURNAL
HEATING MIXES OUT OF THE LOWER LEVELS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...DLF
AVIATION...DR
AREA FORECAST DISCUSSION...CORRECTED
NWS DODGE CITY KS
204 PM CDT TUE JUL 30 2013
...UPDATED FOR THE SHORT TERM DISCUSSION...
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 156 PM CDT TUE JUL 30 2013
TODAY IS SEEING A VERY SLOW CLEARING PATTERN IN THE CLOUDS, FROM
WEST TO EAST. THIS SLOWNESS IN CLEARING IS PARTIALLY DUE TO THE
NORTH TO NORTHEAST LOW LEVEL FLOW, WHICH IS A SLIGHT UPSLOPE
PATTERN. THE OTHER REASON THE EAST IS SO SLOW TO CLEAR OUT IS THE
ABUNDANT SURFACE MOISTURE ACROSS OUR EASTERN ZONES, WITH PLENTY OF
LEFTOVER RAINFALL STILL ACROSS MUCH OF THE EASTERN FORECAST AREA,
ESPECIALLY SOUTHEAST OF A LINE FROM LA CROSSE TO ASHLAND. SOME OF
THESE COUNTIES RECEIVED OVER 3 INCHES OF RAINFALL MONDAY EVENING,
ESPECIALLY ACROSS PRATT AND BARBER COUNTIES. FOR THIS REASON, ALONG
WITH EXPECTED CLEAR SKIES AND LIGHT WINDS EXPECTED, THERE SHOULD
BE SOME MORE FOG FORM TOWARD 09Z TO 10Z. I HAVE DECIDED TO PUT IN
PATCHY FOG WORDING FOR NOW ACROSS OUR SOUTHEASTERN SECTIONS, AND
LATER SHIFTS CAN UPDATE TO DENSE FOG IF IT FORMS. BOTH THE NAM
AND THE HRRR MODELS ARE INDICATED AROUND 1SM VISIBILITIES IN FOG.
AS FOR LOW TEMPERATURES, NO CHANGES WERE MADE TO THE PREVIOUS
FORECAST. CLEAR SKIES AND LIGHT WINDS WILL ALLOW TEMPERATURES TO
DROP TO THE MID 60S IN OUR WEST AND THE UPPER 60S IN OUR
SOUTHEAST.
MOSTLY SUNNY SKIES AREA EXPECTED WEDNESDAY, AFTER SOME SCATTERED
MORNING FOG. WINDS WILL BE LIGHT AND VARIABLE EARLY, THEN SHIFT TO
THE SOUTHEAST IN THE AFTERNOON AT 10 TO 20 MPH. THE SOUTHEASTERN
FLOW WILL BE AN UPSLOPE PATTERN, WITH THE MOISTURE RIDING UP HILL
WHICH MAY COLLIDE WITH THE LATE AFTERNOON TROUGH MOVING EAST FROM
COLORADO. HOW FAST THIS UPSLOPE AND TROUGH INTERACTION WILL
DEVELOP INTO CONVECTION IS HANDLED DIFFERENTLY BY THE MODELS. THE
NAM MODEL BRINGS IN THUNDERSTORMS WEDNESDAY AFTERNOON AS EARLY AS
19Z IN OUR NORTHWEST ZONES OF SCOTT AND LANE COUNTIES, AND
ADVANCES THE RAIN TOWARD DODGE CITY AS EARLY AS 22Z. THE ECMWF AND
GFS MODELS ARE A LITTLE SLOWER, BRINGING RAIN TO SCOTT AND LANE
COUNTIES AFTER 22Z AND NOT NEAR DODGE CITY UNTIL AFTER 02Z. HAVE
STARTED SLIGHT 20 PERCENT CHANCES IN OUR FAR NORTHWEST, SUCH AS
SCOTT AND LANE COUNTIES, AND DELAYED THE ONSET OF CHANCE POP
CATEGORIES IN THE DODGE CITY AREA UNTIL 03Z. SOME OF THE LATE
AFTERNOON AND EVENING STORMS COULD BE STRONG TO SEVERE
SUPPER CELLS, CAPABLE OF STRONG DOWNBURST WINDS AND MARGINAL HAIL
IN THE GOLF BALL SIZE. THE TROUGH BOUNDARY WILL MOVE THROUGH
WESTERN AND INTO CENTRAL KANSAS BY WEDNESDAY EVENING, BRINGING
RAIN CHANCES FOR SHOWERS AND THUNDERSTORMS TO THE PRATT AND
COLDWATER AREAS AFTER 00Z THURSDAY. WITH SKIES STARTING OUT
WEDNESDAY MORNING AS MOSTLY SUNNY, THEN BECOMING PARTLY CLOUDY BY
MID TO LATE AFTERNOON, AND POSSIBLY EVEN MOSTLY CLOUDY BY EVENING,
MAXIMUM TEMPERATURES COULD BE A LITTLE TRICKY. STAYED WITH THE
PREVIOUS FORECAST OF MID 90S IN THE WEST AND NEAR 90F IN THE EAST.
HOW MUCH RAIN WILL FALL IS ALWAYS A LITTLE CHALLENGING, BUT I
THINK THE QPF_FM_POP PROCEDURE DID A FAIRLY GOOD JOB WITH FORECAST
RAINFALL.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 348 AM CDT TUE JUL 30 2013
MEDIUM RANGE MODELS INDICATE A NORTHWESTERLY FLOW ALOFT DEVELOPING
ACROSS THE WESTERN HIGH PLAINS AS UPPER LEVEL RIDGING BUILDS ACROSS
THE INTERMOUNTAIN WEST WEDNESDAY. MEANWHILE, AN UPPER LEVEL
SHORTWAVE TROUGH WILL DROP SOUTHEAST OUT OF THE NORTHERN PLAINS INTO
THE UPPER MIDWEST DURING THE DAY. A WEAK COLD FRONT ASSOCIATED WITH
THE SHORTWAVE IS PROJECTED TO MOVE SLOWLY SOUTHEAST INTO WESTERN
KANSAS BEFORE STALLING OUT BY WEDNESDAY AFTERNOON. ALONG WITH
FAVORABLE DYNAMIC SUPPORT ALOFT, AMPLE LOW LEVEL MOISTURE AND THE
INCREASED LOW LEVEL FORCING ASSOCIATED WITH THE BOUNDARY WILL SET
THE STAGE FOR THUNDERSTORM DEVELOPMENT ACROSS PORTIONS OF CENTRAL
AND SOUTHWEST KANSAS WEDNESDAY AFTERNOON AND EVENING.
FOR THURSDAY, THE UPPER LEVEL RIDGE IS PROGGED TO DRIFT EASTWARD
ACROSS THE DESERT SOUTHWEST WHILE H5 VORT MAXES CONTINUE TO TOP
THE RIDGE AXIS THEN DROP SOUTHEAST INTO THE WESTERN HIGH PLAINS.
MEANWHILE, LEE SIDE TROUGHING IS EXPECTED TO DEVELOP IN EASTERN
COLORADO AS SURFACE HIGH PRESSURE SETS UP ACROSS THE MISSISSIPPI
RIVER VALLEY PROVIDING INCREASED SURFACE CONVERGENCE ACROSS
WESTERN KANSAS, NOT TO MENTION SURFACE DEWPOINTS WELL UP INTO THE
60S(F) TO NEAR 70F. WITH PLENTY OF INSTABILITY PRESENT,
THUNDERSTORMS WILL BE POSSIBLE LATE THURSDAY AFTERNOON AND
EVENING, ESPECIALLY ACROSS WEST CENTRAL AND CENTRAL KANSAS WHERE
BETTER LOW LEVEL FORCING IS LIKELY TO BE PRESENT. CHANCES FOR
THUNDERSTORMS WILL CONTINUE FRIDAY GOING INTO THE WEEKEND WITH
LITTLE CHANGE EXPECTED TO THE OVERALL PATTERN AND A FRONTAL
BOUNDARY LINGERING GENERALLY ACROSS WESTERN KANSAS.
TEMPERATURES WILL BE NEAR NORMAL WEDNESDAY AS A GRADUAL WARMING
TREND CONTINUES ACROSS WESTERN KANSAS. WARMER H85 TEMPERATURES WILL
SLOWLY ADVECT NORTHWARD INTO THE AREA WITH VALUES RANGING FROM THE
MID 20S(C) ACROSS CENTRAL KANSAS TO NEAR 30C NEAR THE COLORADO
BORDER. WITH STEEP LAPSE RATES DEVELOPING IN THE LOWER LEVELS
IN THE AFTERNOON, EXPECT HIGHS WELL UP INTO THE 90S(F). WIDESPREAD
90S(F) ARE LIKELY THURSDAY AFTERNOON WITH NEAR 100F POSSIBLE IN
EXTREME SOUTHWEST KANSAS AS A MODEST LOW LEVEL FLOW CONTINUES TO
ADVECT WARMER AIR INTO WESTERN KANSAS. THE MORE SEASONAL
TEMPERATURES ARE EXPECTED TO CONTINUE INTO THE WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1145 AM CDT TUE JUL 30 2013
IN THE NEAR TERM, EXPECT MVFR CIGS AND GOOD VSBYS. WINDS WILL BE
FROM THE NORTHEAST TODAY IN THE 8 KNOT RANGE. SKIES WILL CLEAR
FROM WEST TO EAST GRADUALLY, BECOMING SCATTERED AT 250 THIS
EVENING. LIGHT WINDS AND ABUNDANT LOW LEVEL MOISTURE WILL LEAD TO
SOME FOG DEVELOPING AFTER 09Z. FOR NOW, I AM EXPECTING SOME 2SM
IFR FOG POSSIBLE, WITH A CHANCE FOR ISOLATED VSBYS LESS THAN 1
MILE IN FOG.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 66 93 68 93 / 10 20 30 20
GCK 66 94 68 94 / 20 30 40 30
EHA 67 95 67 95 / 20 30 40 20
LBL 68 95 69 95 / 20 30 40 20
HYS 65 89 68 92 / 10 30 30 40
P28 69 89 70 94 / 10 10 30 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURKE
LONG TERM...JJOHNSON
AVIATION...BURKE
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
645 PM EDT TUE JUL 30 2013
.UPDATE...
ISSUED AT 645 PM EDT TUE JUL 30 2013
22Z SFC ANALYSIS SHOWS THAT OUR COOL HIGH PRESSURE IS NOW RETREATING
TO THE EAST IN THE FACE OF A DEVELOPING AREA OF LOW PRESSURE LIFTING
INTO THE MID MISSISSIPPI VALLEY. AHEAD OF THIS LOW...AN MCV IN THE
MID LEVELS OF THE ATMOSPHERE IS PUSHING EAST INTO KENTUCKY THIS
EVENING. THIS IS HELPING TO SUSTAIN A LARGE AREA OF LIGHT TO MODERATE
RAIN SLOWLY CROSSING THE BLUEGRASS STATE. FOR EAST KENTUCKY...SO
FAR...THIS HAS MEANT LITTLE MORE THAN SOME VIRGA OVER THE CUMBERLAND
VALLEY BUT MORE SUBSTANTIAL SHOWERS ARE NOT FAR OUT. EXPECT THE RAIN
TO OVERTAKE THE CWA THROUGH THE LATE EVENING AND EARLY MORNING HOURS
FROM WEST TO EAST. A STRAY BOLT OF LIGHTNING WILL BE POSSIBLE THROUGH
THE NIGHT ALONG WITH HEAVIER AMOUNTS OF RAIN FOR THE SOUTHEAST PARTS
OF THE AREA PER THE LATEST NAM12 AND HRRR GUIDANCE. HAVE UPDATED THE
FIRST TWO PERIODS OF THE FORECAST TO REFLECT THIS. ALSO ADJUSTED
TEMPERATURES AND DEWPOINTS THROUGH THE NIGHT IN LINE WITH THE LATEST
THOUGHTS ON PCPN CHANCES AND QPF. UPDATES HAVE BEEN SENT TO THE NDFD
AND WEB SERVERS...ALONG WITH A FRESHENED SET OF ZONES.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 250 PM EDT TUE JUL 30 2013
SFC WARM FRONT FROM SRN ILL TO MIDDLE TENN AND SLOWLY CREEPING TO THE
NE. CURRENT PCPN APPEARS TO BE EDGING INTO MIDDLE KY. CURRENT CLOUD
COVER OVER ERN KY IS HIGH CI WITH SOME MID LEVEL CLOUDS AND VIRGA
EDGING INTO OUR SWRN COUNTIES. SKEW-T INDICATES A WEAK SPEED MAX AT
50H COINCIDENT WITH A VERY MOIST LAYER ABOVE AND VERY DRY BELOW THAT
MAX. SHOULD SEE A GRADUAL MOISTENING OF THE LOWER LAYERS AND A
LOWERING OF THE CEILING HEIGHTS THIS EVENING INTO TONIGHT.
MODELS INDICATE THE PCPN ENTERING THE I-75 CORRIDOR AROUND MIDNIGHT
TONIGHT AS A COLD FRONT SWEEPS ACROSS THE OHIO VALLEY OVERNIGHT. THE
COLD FRONT WILL PROVIDE THE BEST RAINFALL EARLY THU BEFORE BECOMING
NEARLY STATIONARY JUST EAST OF THE APPALACHIAN MTNS WITH SEVERAL
SHORT WAVES DROPPING FROM THE GREAT LAKES TO REINFORCE THE ERN TROF.
EACH SHORT WAVE WILL BRING ANOTHER QUICK SHOT OF PCPN BUT THE
RAINFALL ON WED NITE AND THU WILL NOT BE AS HEAVY OR WIDESPREAD WITH
THE FRONTAL BNDRY HAVING WRUNG MUCH OF THE AVAILABLE MOISTURE FROM
THE AIR. THE LAST OF THE SHRA SHOULD EASE OUT OF THE STATE ON THU
MORNING WITH THE SKY BEGINNING TO CLEAR THU AFTERNOON.
CLOUD COVER AND AN INCREASE IN DEW POINTS WILL HOLD TEMPS TONIGHT IN
THE LOWER 60S. WITH THE INFLUX OF RAIN ON WED BEFORE DROPPING TO THE
MID 60S WED NITE. THEN WITH AN END TO THE RAIN AND SOME HELP FROM
BREAKS IN THE CLOUD COVER ON THU AFTERNOON...TEMPS COULD SHOOT UP TO
THE LOWER 80S. THU HIGHS ARE PREDICATED ON SOME CLEARING...SO IF THE
CLOUDS REMAIN THE HIGHS WILL NECESSARILY NEED TO BE LOWERED SOME.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 251 PM EDT TUE JUL 30 2013
THE MODELS START OFF IN VERY GOOD AGREEMENT WITH UPPER TROUGHS OVER
BOTH COASTS AND AN UPPER RIDGE OVER THE ROCKIES. WITH THIS TYPE OF
PATTERN...SYSTEMS FROM THE WEST COAST ARE BEING BLOCKED BY THE RIDGE
FROM MOVING ACROSS THE AREA. ALL THE SYSTEMS THAT COME THROUGH THE
AREA COME FROM ARES FAR TO THE NORTH AND THEN MOVE DOWN THE BACK OF
THE UPPER TROUGH. THIS SHOULD RESULT IN CONTINUED COOL WEATHER FOR
THIS TIME OF YEAR. BY SUNDAY...THE TIMING OF THE SYSTEMS STARTS TO
BECOME LESS CERTAIN AS THE MODELS DIFFER IN THE TIMING OF THE SHORT
WAVES MOVING DOWN THE BACK SIDE OF THE TROUGH. THE GFS HAS A FRONT
MOVING THROUGH THE AREA ON SATURDAY AND HAS THE LAST OF THE
PRECIPITATION MOVING OUT OF THE AREA SUNDAY MORNING. THE 00Z ECMWF
IS A LITTLE SLOWER WITH MOVING THE RAIN OUT. THE GFS BRINGS THE NEXT
SYSTEM THROUGH ON TUESDAY WHILE THE THE 00Z ECMWF THEN DOES NOT MOVE
THE NEXT SYSTEM INTO THE AREA UNTIL WEDNESDAY. WILL STAY WITH A
MODEL BLEND FOR TIMING AND THEN NUDGE IT TOWARD THE NEW ECMWF
FORECAST WHEN IT COMES IN AT 3 PM. FOR TEMPERATURES STAYED CLOSE
STAYED A BIT COOLER THAN MOS...BUT DID NOT MAKE ANY LARGE CHANGES
FROM THE CONSENSUS MODEL BLEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 119 PM EDT TUE JUL 30 2013
AN AREA OF SURFACE HIGH PRESSURE WILL GRADUALLY SHIFT EAST OF THE OH
VALLEY TODAY. THIS WILL KEEP VFR CONDITIONS ACROSS THE AREA THROUGH
THE MAJORITY OF THE TIME...ALTHOUGH CLOUDS WILL THICKEN AND LOWER
OUT AHEAD OF AN APPROACHING UPPER LEVEL DISTURBANCE. SOME CONVECTION
SHOULD THREATEN THE INTERSTATE 75 CORRIDOR BETWEEN 0Z AND 6Z AND
OVERSPREAD MOST OF THE AREA BY 9Z. AS THE RA MOISTENS THE AIR MASS...
LOOK FOR VSBY AND CIGS TO LOWER TO MVFR TO IFR VALUES. HAVE NOT YET
BROUGHT IN TSRA/VCTS ALTHOUGH THIS IS A POSSIBILITY BY LATE MORNING
AND A GOOD CHANCE BY EARLY WED AFTERNOON.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...DUSTY
LONG TERM...JJ
AVIATION...DUSTY
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
314 PM EDT TUE JUL 30 2013
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 314 PM EDT TUE JUL 30 2013
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A WNW FLOW ALF
OVER THE NRN TIER CONUS AND OVER THE UPR LKS BTWN A SPRAWLING RDG
OVER THE S AND A TROF OVER CNTRL CANADA. SOME SCT -SHRA ASSOCIATED
WITH A DISTURBANCE THRU ONTARIO JUST N OF LK SUP IMPACTED UPR MI
EARLIER IN THE DAY...BUT THE ARRIVAL OF MUCH DRIER AIR ALF SHOWN
BEST ON THE 12Z MPX...ABERDEEN SDAKOTA...AND BISMARCK RAOBS IS
CAUSING THE SHRA TO DIMINISH THIS AFTN. STRONG CAPPING DEPICTED ON
THE LOCAL AND THOSE UPSTREAM RAOBS HAS PREVENTED ANY TS. THE CLDS
ARE A BIT MORE RESILIENT ESPECIALLY OVER THE W WITH LINGERING LLVL
MSTR SHOWN ON THOSE UPSTREAM RAOBS. FARTHER TO THE W...ANOTHER
SHRTWV MOVING FM THE NRN ROCKIES INTO THE NRN PLAINS IS INTERACTING
WITH THE MUCH MOISTER ENVIRONMENT SHOWN ON THE 12Z GLASGOW MT RAOB
AND CAUSING MORE SHRA/TS TO EXPAND INTO THE NRN PLAINS.
MAIN FCST CONCERNS IN THE SHORT TERM ARE CLD TRENDS/IMPACT ON TEMPS
TNGT AND THEN SHRA/TS CHCS LATE TNGT THRU WED ASSOCIATED WITH
DISTURBANCE NOW ROLLING INTO THE NRN PLAINS.
TNGT...WITH DRYING ALF AND LOSS OF DAYTIME HEATING...ANY LINGERING
DIURNAL -SHRA SHOULD DIMINISH ANRD 00Z...WITH THE MORE PERSISTENT
ACTIVITY ALONG DECAYING LK BREEZE BNDRY OVER THE NCENTRAL. SUPRISED
SEVERAL OF THE MODELS GENERATE PCPN THRU MUCH OF THE NGT. BUT
CONSIDERING THE MAGNITUDE OF THE DRYING SHOWN ON THE UPSTREAM RAOBS
AND LACK OF ANY SGNFT H85 THETA E ADVCTN...SUSPECT THE REST OF THE
EVNG WL FEATURE DRY WX WITH THIS MID LVL DRY AIR DOMINATING. MORE
SHRA MAY ARRIVE OVER THE W LATER TNGT AS DPVA/HGT FALLS IN ADVANCE
OF NEXT SHRTWV PUSH INTO THE AREA AND ERODE MID LVL CAPPING AND
MOISTEN THE MID LVLS. BUMPED UP POPS OVER THE W TO ACCOUNT FOR MODEL
TRENDS TOWARD FASTER ARRIVAL OF THIS DYNAMIC FORCING.
WED...SHRA/EMBEDDED TS OVER THE W IN THE MRNG IN ADVANCE OF INCOMING
SHRTWV/ATTENDANT COLD FNT WL MOVE E THRU THE DAY WITH FAIRLY POTENT
DPVA/DEEP LYR QVECTOR CNVGC. A GOOD AMOUNT OF CLD COVER/FCST NEUTRAL
TO NEGATIVE H85 THETA E ADVCTN WL LIMIT HOW MUCH DEEPER LAPSE RATES
CAN DESTABILIZE...AND MODEL FCST SDNGS SHOW NARROW/SKINNY CAPE
DESPITE MUCAPE AS HI AS 1000J/KG. SO SUSPECT SEVERE WX THREAT WL BE
QUITE LIMITED DESPITE STRENGTH OF SHRTWV/12HR HGT FALLS UP TO 60M
DURING DIURNAL HEATING TIME/DEEP LYR SHEAR 30-35KTS...ESPECIALLY
SINCE MODELS HAVE TRENDED FASTER WITH THE SHRTWV PASSAGE/COLD FROPA.
THE BETTER CHC FOR MORE WDSPRD AND STRONGER SHRA/TS WOULD BE OVER
THE E...WHERE LATER ARRIVAL OF THE FNT MIGHT ALLOW FOR MORE DIURNAL
ENHANCEMENT.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 241 PM EDT TUE JUL 30 2013
MUCH OF THIS TIME PERIOD WILL BE PLAGUED BY AFTERNOON SHOWERS OR
POSSIBLE THUNDERSTORMS ACROSS MAINLY CENTRAL UPPER MICHIGAN...THANKS
TO PERSISTENT NW FLOW ALOFT USHERING IN NEARLY DAILY DISTURBANCES
THAT WILL BE ENHANCED BY DAYTIME HEATING AND POTENTIAL LAKE BREEZES.
EXPECT A NEARLY STEADY FORECAST OF THROUGH TUESDAY OF LOWS IN THE
50S /WITH A FEW UPPER 40S/ AND HIGHS IN THE 60S TO LOW 70S /WARMEST
SOUTH CENTRAL/.
BY WEDNESDAY EVENING THE MAIN SYSTEM WILL BE ON ITS WAY OUT...WITH
THE 500MB LOW SET UP ACROSS NORTHERN ONTARIO AND A BROAD TROUGH
EXTENDING FROM ALBERTA AND SASKATCHEWAN THROUGH WI AND MI. THE SLOW
MOVING SFC LOW SHOULD BE OVER N ONTARIO...WITH A COLD FRONT
EXTENDING ACROSS E UPPER MI. BEHIND THE FRONT...LIGHT W TO WNW FLOW
WILL BE THE RULE NEAR THE SFC...WITH THE SFC TROUGH SLOWLY EXITING
EASTWARD BY THE END OF THE WORK WEEK. A SECONDARY COLD FRONT/TROUGH
WILL CROSS THE REGION LATE THURSDAY AFTERNOON...WITH ANOTHER GOOD
CHANCE OF SHOWERS OR THUNDERSTORMS MAINLY INLAND FROM LAKE SUPERIOR.
HIGH PRESSURE WILL ENCOMPASS UPPER MI AND LAKE SUPERIOR LATE FRIDAY
THROUGH SUNDAY. THE GFS AND ECMWF ARE IN A SLIGHT DISAGREEMENT BY
SUNDAY NIGHT...WHICH CONTINUES THROUGH THE REMAINDER OF THE FCST
PERIOD. IT ALL STEMS FROM TIMING OF THE NEXT WAVES SWINGING IN FROM
THE NW...WITH THE GFS BUILDING IN A MORE ROBUST RIDGE AT THE SFC AND
ALOFT SUNDAY NIGHT. EXPECT WAA TO BEGIN OVER THE W LATE
SUNDAY...WITH HIGH CLOUDS ENCROACHING IN ADVANCE OF LOW PRESSURE
ORGANIZING ACROSS THE PLAINS STATES. WE MAY END UP DRY ON
MONDAY...AS THE 30/00Z IS MUCH WEAKER AND SLOWER WITH THE LOW WHEN
COMPARED TO THE 30/12Z GFS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 126 PM EDT TUE JUL 30 2013
EXPECT DRY WX/VFR CONDITIONS TO PREVAIL AT ALL 3 TAF SITES UNTIL
LATE TNGT DESPITE SOME MID CLDS AS DRY LLVL AIR LINGERS. SOME SHRA
WL ARRIVE LATER TNGT/WED MRNG W-E IN ADVANCE OF AN APRCHG COLD FNT.
ALTHOUGH SOME MVFR CONDITIONS COULD OCCUR UNDER ANY HEAVIER SHRA...
LINGERING DRY LLVL AIR SHOULD BRING PREDOMINANT VFR WX.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 314 PM EDT TUE JUL 30 2013
EXPECT WINDS NO HIGHER THAN 20 KTS THIS FORECAST PERIOD WITH A WEAK
PRESSURE GRADIENT DOMINATING THE UPPER GREAT LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS HASTINGS NE
250 PM CDT TUE JUL 30 2013
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 246 PM CDT TUE JUL 30 2013
MAIN UPPER LEVEL SCENARIO INCLUDES A PERSISTENT SUBTROPICAL RIDGE
OVER THE SOUTHERN UNITED STATES. SPLIT JET WITHIN QUASI-ZONAL FLOW
IN THE NORTH CONTAINS A SHORTWAVE TROUGH SKIRTING ACROSS THE
NORTHERN PLAINS WHICH SHOULD DEVELOP A LONG ADVERTISED MCS OVER
SOUTH DAKOTA THAT SHOULD MAKE ITS WAY SOUTHEAST...AND COULD JUST
SWIPE THE CWA IN THE NORTH BY LATE TONIGHT. THERE COULD BE ENOUGH
SHEAR TO GET SOME STRONG TO SEVERE WEATHER FROM THE REMNANTS OF THE
EXPECTED MCS. CONVERGENCE ALONG AN APPROACHING COLD FRONT WILL ALSO
INCREASE PRECIPITATION AND SEVERE THUNDERSTORM CHANCES. AS A SIDE
NOTE...SKY COVER IS DIFFICULT TO FORECAST FOR THIS EVENING...AND I
HAVE CURBED THE ENTHUSIASM OF MOST MODELS FOR CLEARING...AS EVEN
THE HRRR HAS SHOWN TOO MUCH OPTIMISM FOR THE CLEARING.
ALSO...MODELS HAVE CONTINUED TO ADVERTISE A FAIRLY STRONG SIGNAL FOR
FOG AND HAVE BEEN PRETTY CONSISTENT AS STRATUS IS FORECAST TO
LOWER UNTIL WE GET DENSE FOG IN OUR EAST. CONFIDENCE IS HIGHER WITH
THE RECENT CONSISTENCY...AND A FAIRLY STRONG SIGNAL IN THE
EASTERN THIRD OF THE CWA PERSISTS...PROMPTING ME TO ISSUE A DENS
FOG ADVISORY FOR LATE TONIGHT INTO WEDNESDAY MORNING.
A COLD FRONT WILL MAKE ITS WAY ACROSS THE CWA FOR WEDNESDAY AND WILL
BE THE FOCUS FOR MORE POSSIBLE SEVERE WEATHER. DEWPOINTS ARE
EXPECTED TO POOL NEAR THE BOUNDARY WITH INCREASED INSTABILITY ALONG
THE FRONT...AND CONTINUED LOW-LEVEL CONVERGENCE. BULK SHEAR WILL
ALSO BE SUFFICIENT ENOUGH FOR SEVERE WEATHER...EVEN IF THERE ARE
LIMITED BREAKS IN SKY COVER. THIS COULD WIND UP BEING A POTENTIALLY
INTERESTING DAY DEPENDING ON THE TIMING OF THE COLD FRONT. KEPT A
CHANCE OF PRECIPITATION NEAR THE FRONT...SIMILAR TO THE PREVIOUS
FORECAST.
BASED TEMPERATURES AND DEWPOINTS ON RECENT MODEL PERFORMANCE AND NOT
MUCH HAS CHANGED FOR THESE FIELDS COMPARED TO THE PREVIOUS
FORECAST...EXCEPT PERHAPS HIGHER DEWPOINTS NEAR THE PROJECTED TIMING
AND PLACEMENT OF THE COLD FRONT.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 246 PM CDT TUE JUL 30 2013
GUIDANCE SUGGESTS NORTHWESTERLY MID TO UPPER LEVEL FLOW WILL PERSIST
OVER THE CENTRAL PLAINS THROUGH MUCH OF THE LONG TERM FORECAST
PERIOD. WITH MULTIPLE MID LEVEL PERTURBATIONS PERHAPS MOVING OVER
THE AREA WITHIN THE MEAN MID LEVEL FLOW...POPS REMAIN LITTERED
THROUGHOUT MOST ALL OF THE LONG TERM FORECAST PERIOD. OUT OF ALL THE
LONG TERM FORECAST PERIODS...THE HIGHEST CONFIDENCE WITH RESPECT TO
POPS EXISTS DURING THURSDAY AND THURSDAY NIGHT. THESE ARE TIME
PERIODS IN WHICH GUIDANCE SUGGESTS LOW LEVEL THERMAL ADVECTION AND
RESULTANT ISENTROPIC UPGLIDE AND SATURATION...PRIMARILY ALONG THE
315-320K SURFACES...WILL PERSIST. THIS THERMAL ADVECTION...WORKING IN
CONCERT WITH OMEGA FROM MID LEVEL PERTURBATIONS PUSHING
OVERHEAD...SHOULD BE STRONG ENOUGH TO PROMOTE PRECIPITATION
PRODUCTION ACROSS MUCH OF OUR AREA. TAKING A AVERAGE OF THE
NAM...OPERATIONAL GFS...EC...AND SREF-MEAN PROVIDES BETWEEN A
QUARTER INCH AND A HALF INCH OF RAIN ACROSS MUCH OF OUR CWA DURING
THE DAY THURSDAY...AND MUCH OF THE SAME ACROSS OUR EAST THURSDAY
NIGHT. WENT AHEAD AND INCREASED POPS ACROSS MUCH OF OUR CWA THURSDAY
INTO THURSDAY NIGHT AS A RESULT. POPS ALSO CONTINUE ACROSS OUR AREA
FOR THE MOST PART HEADING INTO FRIDAY BEFORE THE PRIMARY AXIS OF
THERMAL ADVECTION FINALLY EXITS THE AREA TO THE EAST. AS MENTIONED
ALREADY...THE POTENTIAL FOR MID LEVEL PERTURBATIONS MOVING OVER THE
AREA SUGGESTS POPS REMAIN WARRANTED ACROSS OUR AREA THROUGH THE
REMAINDER OF THE EXTENDED FORECAST PERIOD. ALLBLEND PROVIDED A
VARIETY OF POPS TO OUR AREA EACH DAY...GENERALLY IN THE 20-40%
RANGE...AND GIVEN THE LOW PROBABILITY OF IMPROVING THE FORECAST
THESE POPS WERE LEFT UNCHANGED FOR THE MOST PART.
INCREASING LOW LEVEL RETURN FLOW AND RESULTANT MOISTURE FLUX INTO
THE AREA SHOULD HELP PROMOTE RESPECTABLE VALUES OF POTENTIAL
INSTABILITY ON THURSDAY...WITH GUIDANCE FROM THE NAM...OPERATIONAL
GFS...AND EC SUGGESTING MUCAPE VALUES RANGING BETWEEN 1500 AND
3500J/KG ACROSS OUR CWA. DEEP LAYER BULK SHEAR VALUES OF 35-45KTS
ARE ALSO FORECAST ACROSS THE AREA ON THURSDAY. THERE IS A CONCERN
THAT EXPANSIVE CLOUD COVER WILL KEEP LOW LEVEL TEMPERATURES ON THE
COOL SIDE WHICH WOULD HELP PRESERVE A LOW LEVEL CAPPING
INVERSION...WHICH WOULD OBVIOUSLY INHIBIT STRONG/DEEP CONVECTION
FROM BEING REALIZED. THAT BEING SAID...IF NEAR-SURFACE BASED
CONVECTION CAN BE REALIZED THURSDAY...THEN CERTAINLY SEVERE WEATHER
WILL BE POSSIBLE AND WILL INTRODUCE SUCH WORDING TO THE HWO. BEYOND
THURSDAY...GUIDANCE SUGGESTS MUCAPE VALUES IN EXCESS OF 2000J/KG
COULD BE REALIZED MOST ANY DAY...BUT AS ALREADY MENTIONED CONFIDENCE
ON WHEN AND WHERE CONVECTION WILL BE REALIZED IS VERY LOW AND AS A
RESULT...WILL MAINTAIN VAGUE SEVERE WEATHER WORDING IN THE HWO FOR
FRIDAY AND BEYOND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1256 PM CDT TUE JUL 30 2013
TRICKY CALL WITH HOW QUICKLY THE STRATUS WILL ERODE FROM THE WEST.
CEILINGS SHOULD RISE AND THEN SCATTER OUT THIS AFTERNOON. THERE IS
A CHANCE OF MORE MVFR OR LOWER STRATUS AND SOME REDUCED VISIBILITY
FOR TONIGHT...BUT THE MAJORITY OF POORER CEILINGS AND VISIBILIIY
SHOULD REMAIN JUST EAST OF THE TERMINAL.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...DENSE FOG ADVISORY FROM 4 AM TO 10 AM CDT WEDNESDAY FOR NEZ041-
048-049-063-064-076-077-086-087.
KS...DENSE FOG ADVISORY FROM 4 AM TO 10 AM CDT WEDNESDAY FOR KSZ007-
019.
&&
$$
SHORT TERM...HEINLEIN
LONG TERM...BRYANT
AVIATION...HEINLEIN
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
239 PM CDT TUE JUL 30 2013
.UPDATE...
ISSUED AT 238 PM CDT TUE JUL 30 2013
UPDATED ZONES TO ADD WATCH REFRESHED ZONES FOR CURRENT CONDITIONS.
UPDATE ISSUED AT 1255 PM CDT TUE JUL 30 2013
HAVE UPDATED TO RAISE MAX TEMPS THIS AFTERNOON ACROSS THE WEST
WHERE STRONG INSOLATION HAS ALLOWED TEMPS TO WARM INTO THE 80S
ALREADY. HOWEVER...DID NOT CHANGE TEMPS MUCH FURTHER EAST WHERE
LOW CLOUDS REMAIN OR WERE LIMITING SUNSHINE EARLIER THIS MORNING.
ALSO ADJUSTED POPS TO BETTER REFLECT CURRENT THINKING OF
CONVECTION INITIATION. MOST CONVECTION ALLOWING MODELS SUGGEST
CONVECTIVE INITIATION ALONG SURFACE TROUGH/WIND SHIFT BOUNDARY
THAT WILL EXIST FROM NORTH CENTRAL NEBRASKA INTO THE EASTERN
PANHANDLE. COULD BE SOME ENHANCEMENT TO THE CONVERGENCE ALONG THE
BOUNDARY FROM DIFFERENTIAL HEATING DUE TO EARLIER CLOUD
COVER...DEPENDING ON HOW MUCH MIXING EVOLVES FURTHER EAST THIS
AFTERNOON. ALSO COULD BE SOME STORMS THAT MOVE SOUTH INTO THE CWA
FROM SD. OVERALL STILL THINKING BEST THUNDERSTORM CHANCES WILL BE
ACROSS THE NORTH CENTRAL INTO THE SANDHILLS. COVERAGE WILL BE
LIMITED INITIALLY BUT MAY EVOLVE INTO CONVECTIVE CLUSTERS THROUGH
THE LATE AFTERNOON EVENING. MESOANALYSIS SUGGESTS GOOD
DESTABILIZATION OCCURRING ALREADY ALONG THIS BOUNDARY AS IT
DEVELOPS...WITH MLCAPE EXCEEDING 1500 J/KG. SO SOME POTENTIAL FOR
ISOLATED SVR HAIL AND DAMAGING WIND GUSTS AS CONVECTIVE CLUSTERS
DEVELOP.
UPDATE ISSUED AT 950 AM CDT TUE JUL 30 2013
UPDATED FORECAST TO DROP DENSE FOG ADVISORY AND INCREASE CLOUD
COVER THROUGH THE MORNING WITH AREAS OF PATCHY FOG CONTINUING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT TUE JUL 30 2013
TODAY AND TONIGHT...DENSE FOG WOULD APPEAR TO BE VERY SHALLOW
THIS MORNING WITH THE MOON VISIBLE AT KLBF AND NEDOR SHOWING IT
LIFTING AT KLXN. SO WE WOULD EXPECT A RAPID CLEARING AFTER SUNRISE
IN SOME AREAS AS SATELLITE SHOWS AREAS OF STRATUS AT THE SAME TIME
WHICH WOULD SLOW THE LIFTING PROCESS.
A WEAK AND DECAYING MCS ACROSS NWRN NEB/SWRN SD THIS MORNING IN
COMBINATION WITH A WEAK DISTURBANCE OVER ERN COLO COULD PERHAPS
SPREAD ISOLATED SHOWERS AND THUNDERSTORMS INTO WRN NEB.
THE HRRR THEN SHOWS CONVECTIVE DESTABILIZATION ACROSS SWRN NEB BY
20Z WHICH IS PROBABLY AN HOUR OR TWO TOO FAST. THE MAIN IMPULSE
WOULD APPEAR TO BE DROPPING SOUTHEAST THROUGH NERN WY/WRN SD AT
20Z...STILL HOURS AWAY FROM THE FCST AREA. A MCS IS EXPECTED TO
DEVELOP OUT OF THE STORMS FIRING ACROSS THE NRN HIGH PLAINS WHICH
SHOULD SWEEP THRU NRN NEB OVERNIGHT. THE MCS SHOULD REMAIN MOSTLY
ALONG AND NORTH OF HIGHWAY 20.
TEMPERATURES TODAY ARE EXPECTED TO RISE INTO THE LOW TO MID 80S
IN MOST AREAS GIVEN THE CONTINUED SOUTH AND SOUTHEAST WINDS
CIRCULATING AROUND HIGH PRESSURE CENTERED OVER THE MIDWEST. THE
ENSUING WARM AIR ADVECTION FUELING THE MCS TONIGHT SHOULD KEEP
SKIES MOSTLY CLEAR SOUTH OF THE CONVECTIVE COMPLEX. THE NAM12
HINTS AT A BANK OF STRATUS FILLING IN ACROSS NWRN NEB IN THE WAKE
OF THE MCS AROUND 12Z.
SEVERE WEATHER POTENTIAL WITH THE THUNDERSTORMS THIS AFTERNOON
AND TONIGHT IS LIMITED TO 5 PERCENT OR ISOLATED WITH THE BEST
INSTABILITY AND 40 TO 50 KT 1 TO 6 KM SHEAR ACROSS NRN NEB MOSTLY
ASSOCIATED WITH THE DEVELOPING MCS. MODEL INDICATIONS SUGGEST THE
BLACK HILLS COULD BE THE GENESIS FOR A CLUSTER OF STORMS FORMING
LATE IN THE AFTERNOON WHICH WOULD MOVE EAST SOUTHEAST TOWARD
KVTN-KANW-KONL DURING THE EVENING AND OVERNIGHT. THIS IN TURN
COULD CERTAINLY INCREASE THE SEVERE WEATHER POTENTIAL IN THOSE
AREAS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 400 AM CDT TUE JUL 30 2013
WEDNESDAY MORNING LINGER SHOWERS WILL BE POSSIBLE ACROSS PORTIONS
OF CENTRAL/NORTH CENTRAL NEB. THEN BREAKS IN THE CLOUDS SHOULD
HELP TO PUSH HIGHS INTO THE 80S. LATE IN THE DATE MODELS IN
AGREEMENT WITH A BOUNDARY STRETCHED FROM WEST CENTRAL KS
NORTHEAST INTO CENTRAL NEB AND ON TOWARDS THE WESTERN GREAT
LAKES. THUNDERSTORMS WILL BE POSSIBLE ALONG THE SLOW MOVING
BOUNDARY...HOWEVER IMPACT TO THE CWA IN QUESTIONS. THE LATEST NAM
AND GFS HAVE PUSHED THE BOUNDARY JUST SE OF THE CWA BY PEAK
HEATING...HOWEVER THE EC AND GEM DO DEVELOP ACTIVITY IN THE SE
CWA. WILL TREND DOWN WITH POPS...ALTHOUGH STILL RETAIN SLGHT CHC
IN THE FAR SE ZONES. MORE OF A FOCUS WILL BE THE NEXT SHORT WAVE
CROSSING THE ROCKIES. THIS WAVE SHOULD ALLOW DEVELOPMENT ON THE
HIGHER TERRAIN WITH FLOW TO PUSH THIS INTO THE PANHANDLE AND
WESTERN NEBRASKA OVERNIGHT.
THURSDAY WILL SEE YET ANOTHER SHORT WAVE TO PUSH ACROSS THE AREA.
MODELS CONTINUE TO SHOW GOOD INSTABILITY WITH DECENT SHEAR...ALSO
WILL SEE A SURF LOW DEVELOP NEAR NE CO. ANY ACTIVITY DEVELOPING IN
THE EVENING FROM PEAK HEATING WILL LIKELY BE SUSTAINED BY A 30 TO
40K LL JET. LOW FREEZING LEVEL WITH STEEP LAPSE RATE SHOULD RESULT
IN A FEW STRONG TO EVEN SEVERE STORMS...WITH HAIL THE MAIN THREAT.
FRIDAY WILL SEE AN UPPER LEVEL LOW COME ONSHORE TO THE PAC
NW...THIS WILL FLATTEN THE RIDGE AND PUSH IT EASTWARD. INITIALLY
THOUGHT THERE COULD BE A WARM UP...HOWEVER MODELS CONTINUE TO
BRING GOOD MOISTURE AROUND THE RIDGE...RESULTING IN MORE CLOUDS
THAN SUN. FORECAST RESULTS IN BELOW NORMAL HIGHS...WHICH IS CLOSE
TO MOS GUIDANCE.
LITTLE CHANGES THROUGH THE WEEKEND FOR THE AREA...AS RIDGE REMAINS
TO THE SOUTH AND LOW WILL TRAVERSE ACROSS THE US/CAN BORDER. FLOW
WILL CONTINUE TO BE NORTHWESTERLY TO ZONAL...AND MODELS CONTINUE
TO BRING WAVE AFTER WAVE ACROSS THE AREA. QPF MAY NOT BE
SIGNIFICANT...HOWEVER WILL NEED TO CONTINUE TO MENTION IN NEARLY
EVERY PERIOD PENDING TIMING OF THE WAVES. TEMPS WILL GENERALLY BE
BELOW NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1255 PM CDT TUE JUL 30 2013
HAVE ADDED VCTS IN THE VTN TAF BASED ON THE IDEA OF BETTER
CONVECTIVE COVERAGE ACROSS NC NEBRASKA THIS AFTERNOON AND EVENING.
CONFIDENCE ON COVERAGE FURTHER SOUTH IS NOT AS GOOD AND THEREFORE
LEFT OUT OF THE LBF TAF.
OTHERWISE HAVE GONE WITH MAINLY IFR CONDITIONS THROUGH THE
PERIOD...THOUGH SOME CONCERN ABOUT A REDEVELOPMENT OF LOW CLOUDS
AND/OR FOG AFTER 09Z TONIGHT. THINK BETTER CHANCES FOR THIS WOULD
BE EAST OF VTN TAF SITE SINCE A SHIFT TO A NORTHERLY WIND SHOULD
OCCUR BEFORE ONSET...BUT MAY HAVE TO BE INTRODUCED INTO THE LBF
TAF WITH LATER FCSTS.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...POWER
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...JWS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
137 PM CDT TUE JUL 30 2013
.UPDATE...
ISSUED AT 135 PM CDT TUE JUL 30 2013
UPDATED THE FORECAST FOR THIS AFTERNOON TO LOWER TEMPERATURES IN
THE EASTERN CWA WHERE SKY COVER WILL LINGER LONGER.
UPDATE ISSUED AT 1057 AM CDT TUE JUL 30 2013
ADJUSTED SKY COVER UP FOR THE REMAINDER OF THE MORNING...AND
FOLLOWED CLOSER TO THE HRRR FOR SKY COVER FOR THE REST OF THE DAY
INTO THE NIGHT. THIS MODEL SEEMS TO BE DOING THE BEST HANDLING THE
ERODING WEST SIDE OF THE STROTOCUMULUS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 336 AM CDT TUE JUL 30 2013
AREAS OF FOG HAVE DEVELOPED ACROSS THE REGION OVERNIGHT AS ELEVATED
DEW POINTS AND LIGHT WINDS HAVE AIDED IN ITS FORMATION. AFTER MAKING
A FEW PHONE CALLS AND PERUSING HIGHWAY CAMERAS THE PAST HOUR...HAVE
DECIDED TO GO AHEAD AND EXPAND THE DENSE FOG ADVISORY NORTH AND EAST
WITH THE MORNING FORECAST PACKAGE TO ACCOUNT FOR POCKETS OF DENSE
FOG THAT HAVE FORMED. WHILE MODEL GUIDANCE IS NOT HANDLING THIS FOG
VERY WELL...CANNOT SEE A REASON FOR CONDITIONS TO IMPROVE MUCH
BEFORE SUNRISE...AND WILL KEEP EXPIRATION TIME OF 14Z FOR THE TIME
BEING.
FOR TODAY...ONCE THE FOG BEGINS TO LIFT DURING THE MID MORNING
HOURS...EXPECT A FAIRLY NICE DAY ACROSS THE REGION AS TEMPERATURES
WILL BEGIN TO MODERATE CLOSER TO SEASONAL NORMS...WINDS WILL BE
LIGHT...AND SKIES WILL BEGIN TO CLEAR. WHILE CLOUDY SKIES WILL
ENVELOP THE REGION THROUGH MID MORNING HOURS...EXPECT AT LEAST A
PARTLY SUNNY AFTERNOON AS THE FRONTAL BOUNDARY TO OUR SOUTH...
RESPONSIBLE FOR THE ACTIVE WEATHER ON MONDAY...CONTINUES TO SHIFT
SOUTHEASTWARD.
THEREAFTER THE FOCUS WILL SHIFT NORTHWARD AS SHORTWAVE CROSSING THE
NORTHERN PLAINS...ALONG WITH A SURFACE COLD FRONT...BEGIN TO SAG
SOUTHWARD TOWARDS THE LOCAL AREA. THE LATEST WRF INDICATES A NICE
BAND OF CONVECTION DEVELOPING AHEAD OF THIS WAVE LATE TUESDAY
NIGHT...WHILE THE 06Z NAM/00Z GFS/EC KEEP THE BULK OF THE CONVECTION
NORTH OF THE LOCAL FORECAST AREA. HOWEVER...WITH PLENTY OF ELEVATED
INSTABILITY TO WORK WITH AND SOME SYNOPTIC SCALE FORCING...SIDED
TOWARDS THE MORE AGGRESSIVE SOLUTION OF THE WRF AND INCREASED POPS
ACROSS THE NORTH LATE TUESDAY NIGHT. THAT SAID...KEPT CONVECTION
POTENTIAL GENERALLY NORTH OF I80 DURING THE OVERNIGHT HOURS AS THE
00Z WRF SEEMS TO BE THE OUTLIER TAKING ACTIVITY MUCH FURTHER SOUTH
THAN REMAINDER OF GUIDANCE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 336 AM CDT TUE JUL 30 2013
PRIMARY CONCERN IN THE EXTENDED WILL BE ALMOST DAILY
CHANCES FOR PRECIPITATION. LOOKING AT THE BIG PICTURE...BY
WEDNESDAY MORNING IT APPEARS WE WILL BE IN NORTHWEST FLOW AS MODELS
IN DECENT AGREEMENT IN PLACING A MID LEVEL CUT OFF LOW JUST OFF THE
PACIFIC NORTHWEST COAST...AND ANOTHER ONE OVER WESTERN ONTARIO. IN
BETWEEN THIS IS A DIRTY RIDGE CENTERED OVER THE ROCKIES. THERE
APPEARS TO BE SOME PROGRESSION OF THESE SYSTEMS EASTWARD DURING THE
REST OF THE WORK WEEK...BUT FOR US IT LOOKS LIKE WE COULD HAVE MINOR
SHORTWAVES PASSING THROUGH THE RIDGE. SOME OF THESE MAY PACK A
LITTLE MORE PUNCH AND THE FIRST ONE OF THESE LOOKS TO BE THURSDAY
NIGHT. WILL CONTINUE TO KEEP HIGHEST POPS GOING FOR THURS NIGHT.
BACKING UP JUST A BIT AND CHECKING THE SURFACE FEATURES...IT LOOKS
LIKE THERE WILL BE A WEAK FRONTAL BOUNDARY DROPPING SOUTH ACROSS THE
CWA DURING THE DAYTIME ON WED. THIS COULD HELP TRIGGER THUNDERSTORMS
BY THE AFTERNOON. BY LATE IN THE WEEK AND INTO THE WEEKEND A
FRONTAL BOUNDARY WILL BE SOMEWHERE NEAR THE CWA AND THE INTERACTION
OF PASSING MID LEVEL DISTURBANCES WITH THE SURFACE FEATURE WILL KEEP
OUR WEATHER UNSETTLED.
AS FAR AS SEVERE CHANCES ARE CONCERNED...PROGGED DEEP LAYER SHEAR
LOOKS TO BE IMPRESSIVE...ESPECIALLY FOR THIS TIME OF YEAR...WITH
0-6 KM VALUES OF 20 TO 50 KT NOTED FOR MOST DAYS ON THE LATEST EC
AND/OR GFS RUN. INSTABILITY ALSO IMPRESSIVE WITH MU CAPE NUMBERS
QUITE HIGH. ON THE NEGATIVE SIDE...THERE COULD BE SOME CAPPING
ISSUES ESPECIALLY LATER IN THE WEEK AND INTO THE WEEKEND WITH
PROGGED 700 MB TEMPS EXPECTED TO BE BETWEEN 11 AND 15 DEGREES
CELSIUS..WITH THE GFS A LITTLE WARMER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1256 PM CDT TUE JUL 30 2013
TRICKY CALL WITH HOW QUICKLY THE STRATUS WILL ERODE FROM THE WEST.
CEILINGS SHOULD RISE AND THEN SCATTER OUT THIS AFTERNOON. THERE IS
A CHANCE OF MORE MVFR OR LOWER STRATUS AND SOME REDUCED VISIBILITY
FOR TONIGHT...BUT THE MAJORITY OF POORER CEILINGS AND VISIBILIIY
SHOULD REMAIN JUST EAST OF THE TERMINAL.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HEINLEIN
SHORT TERM...SAR
LONG TERM...EWALD
AVIATION...HEINLEIN
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1258 PM CDT TUE JUL 30 2013
.UPDATE...
ISSUED AT 1057 AM CDT TUE JUL 30 2013
ADJUSTED SKY COVER UP FOR THE REMAINDER OF THE MORNING...AND
FOLLOWED CLOSER TO THE HRRR FOR SKY COVER FOR THE REST OF THE DAY
INTO THE NIGHT. THIS MODEL SEEMS TO BE DOING THE BEST HANDLING THE
ERODING WEST SIDE OF THE STROTOCUMULUS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 336 AM CDT TUE JUL 30 2013
AREAS OF FOG HAVE DEVELOPED ACROSS THE REGION OVERNIGHT AS ELEVATED
DEW POINTS AND LIGHT WINDS HAVE AIDED IN ITS FORMATION. AFTER MAKING
A FEW PHONE CALLS AND PERUSING HIGHWAY CAMERAS THE PAST HOUR...HAVE
DECIDED TO GO AHEAD AND EXPAND THE DENSE FOG ADVISORY NORTH AND EAST
WITH THE MORNING FORECAST PACKAGE TO ACCOUNT FOR POCKETS OF DENSE
FOG THAT HAVE FORMED. WHILE MODEL GUIDANCE IS NOT HANDLING THIS FOG
VERY WELL...CANNOT SEE A REASON FOR CONDITIONS TO IMPROVE MUCH
BEFORE SUNRISE...AND WILL KEEP EXPIRATION TIME OF 14Z FOR THE TIME
BEING.
FOR TODAY...ONCE THE FOG BEGINS TO LIFT DURING THE MID MORNING
HOURS...EXPECT A FAIRLY NICE DAY ACROSS THE REGION AS TEMPERATURES
WILL BEGIN TO MODERATE CLOSER TO SEASONAL NORMS...WINDS WILL BE
LIGHT...AND SKIES WILL BEGIN TO CLEAR. WHILE CLOUDY SKIES WILL
ENVELOP THE REGION THROUGH MID MORNING HOURS...EXPECT AT LEAST A
PARTLY SUNNY AFTERNOON AS THE FRONTAL BOUNDARY TO OUR SOUTH...
RESPONSIBLE FOR THE ACTIVE WEATHER ON MONDAY...CONTINUES TO SHIFT
SOUTHEASTWARD.
THEREAFTER THE FOCUS WILL SHIFT NORTHWARD AS SHORTWAVE CROSSING THE
NORTHERN PLAINS...ALONG WITH A SURFACE COLD FRONT...BEGIN TO SAG
SOUTHWARD TOWARDS THE LOCAL AREA. THE LATEST WRF INDICATES A NICE
BAND OF CONVECTION DEVELOPING AHEAD OF THIS WAVE LATE TUESDAY
NIGHT...WHILE THE 06Z NAM/00Z GFS/EC KEEP THE BULK OF THE CONVECTION
NORTH OF THE LOCAL FORECAST AREA. HOWEVER...WITH PLENTY OF ELEVATED
INSTABILITY TO WORK WITH AND SOME SYNOPTIC SCALE FORCING...SIDED
TOWARDS THE MORE AGGRESSIVE SOLUTION OF THE WRF AND INCREASED POPS
ACROSS THE NORTH LATE TUESDAY NIGHT. THAT SAID...KEPT CONVECTION
POTENTIAL GENERALLY NORTH OF I80 DURING THE OVERNIGHT HOURS AS THE
00Z WRF SEEMS TO BE THE OUTLIER TAKING ACTIVITY MUCH FURTHER SOUTH
THAN REMAINDER OF GUIDANCE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 336 AM CDT TUE JUL 30 2013
PRIMARY CONCERN IN THE EXTENDED WILL BE ALMOST DAILY
CHANCES FOR PRECIPITATION. LOOKING AT THE BIG PICTURE...BY
WEDNESDAY MORNING IT APPEARS WE WILL BE IN NORTHWEST FLOW AS MODELS
IN DECENT AGREEMENT IN PLACING A MID LEVEL CUT OFF LOW JUST OFF THE
PACIFIC NORTHWEST COAST...AND ANOTHER ONE OVER WESTERN ONTARIO. IN
BETWEEN THIS IS A DIRTY RIDGE CENTERED OVER THE ROCKIES. THERE
APPEARS TO BE SOME PROGRESSION OF THESE SYSTEMS EASTWARD DURING THE
REST OF THE WORK WEEK...BUT FOR US IT LOOKS LIKE WE COULD HAVE MINOR
SHORTWAVES PASSING THROUGH THE RIDGE. SOME OF THESE MAY PACK A
LITTLE MORE PUNCH AND THE FIRST ONE OF THESE LOOKS TO BE THURSDAY
NIGHT. WILL CONTINUE TO KEEP HIGHEST POPS GOING FOR THURS NIGHT.
BACKING UP JUST A BIT AND CHECKING THE SURFACE FEATURES...IT LOOKS
LIKE THERE WILL BE A WEAK FRONTAL BOUNDARY DROPPING SOUTH ACROSS THE
CWA DURING THE DAYTIME ON WED. THIS COULD HELP TRIGGER THUNDERSTORMS
BY THE AFTERNOON. BY LATE IN THE WEEK AND INTO THE WEEKEND A
FRONTAL BOUNDARY WILL BE SOMEWHERE NEAR THE CWA AND THE INTERACTION
OF PASSING MID LEVEL DISTURBANCES WITH THE SURFACE FEATURE WILL KEEP
OUR WEATHER UNSETTLED.
AS FAR AS SEVERE CHANCES ARE CONCERNED...PROGGED DEEP LAYER SHEAR
LOOKS TO BE IMPRESSIVE...ESPECIALLY FOR THIS TIME OF YEAR...WITH
0-6 KM VALUES OF 20 TO 50 KT NOTED FOR MOST DAYS ON THE LATEST EC
AND/OR GFS RUN. INSTABILITY ALSO IMPRESSIVE WITH MU CAPE NUMBERS
QUITE HIGH. ON THE NEGATIVE SIDE...THERE COULD BE SOME CAPPING
ISSUES ESPECIALLY LATER IN THE WEEK AND INTO THE WEEKEND WITH
PROGGED 700 MB TEMPS EXPECTED TO BE BETWEEN 11 AND 15 DEGREES
CELSIUS..WITH THE GFS A LITTLE WARMER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1256 PM CDT TUE JUL 30 2013
TRICKY CALL WITH HOW QUICKLY THE STRATUS WILL ERODE FROM THE WEST.
CEILINGS SHOULD RISE AND THEN SCATTER OUT THIS AFTERNOON. THERE IS
A CHANCE OF MORE MVFR OR LOWER STRATUS AND SOME REDUCED VISIBILITY
FOR TONIGHT...BUT THE MAJORITY OF POORER CEILINGS AND VISIBILIIY
SHOULD REMAIN JUST EAST OF THE TERMINAL.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HEINLEIN
SHORT TERM...SAR
LONG TERM...EWALD
AVIATION...HEINLEIN
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1257 PM CDT TUE JUL 30 2013
.UPDATE...
ISSUED AT 1255 PM CDT TUE JUL 30 2013
HAVE UPDATED TO RAISE MAX TEMPS THIS AFTERNOON ACROSS THE WEST
WHERE STRONG INSOLATION HAS ALLOWED TEMPS TO WARM INTO THE 80S
ALREADY. HOWEVER...DID NOT CHANGE TEMPS MUCH FURTHER EAST WHERE
LOW CLOUDS REMAIN OR WERE LIMITING SUNSHINE EARLIER THIS MORNING.
ALSO ADJUSTED POPS TO BETTER REFLECT CURRENT THINKING OF
CONVECTION INITIATION. MOST CONVECTION ALLOWING MODELS SUGGEST
CONVECTIVE INITIATION ALONG SURFACE TROUGH/WIND SHIFT BOUNDARY
THAT WILL EXIST FROM NORTH CENTRAL NEBRASKA INTO THE EASTERN
PANHANDLE. COULD BE SOME ENHANCEMENT TO THE CONVERGENCE ALONG THE
BOUNDARY FROM DIFFERENTIAL HEATING DUE TO EARLIER CLOUD
COVER...DEPENDING ON HOW MUCH MIXING EVOLVES FURTHER EAST THIS
AFTERNOON. ALOS COULD BE SOME STORMS THAT MOVE SOUTH INTO THE CWA
FROM SD. OVERAL STILL THINKING BEST THUNDERSTORM CHANCES WILL BE
ACROSS THE NORTH CENTRAL INTO THE SANDHILLS. COVERAGE WILL BE
LIMITED INITIALLY BUT MAY EVOLVE INTO CONVECTIVE CLUSTERS THROUGH
THE LATE AFTERNOON EVENING. MESOANALYSIS SUGGESTS GOOD
DESTABILIZATION OCCURRING ALREADY ALONG THIS BOUNDARY AS IT
DEVELOPS...WITH MLCAPE EXCEEDING 1500 J/KG. SO SOME POTENTIAL FOR
ISOLATED SVR HAIL AND DAMAGING WIND GUSTS AS CONVECTIVE CLUSTERS
DEVELOP.
UPDATE ISSUED AT 950 AM CDT TUE JUL 30 2013
UPDATED FORECAST TO DROP DENSE FOG ADVISORY AND INCREASE CLOUD
COVER THROUGH THE MORNING WITH AREAS OF PATCHY FOG CONTINUING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT TUE JUL 30 2013
TODAY AND TONIGHT...DENSE FOG WOULD APPEAR TO BE VERY SHALLOW
THIS MORNING WITH THE MOON VISIBLE AT KLBF AND NEDOR SHOWING IT
LIFTING AT KLXN. SO WE WOULD EXPECT A RAPID CLEARING AFTER SUNRISE
IN SOME AREAS AS SATELLITE SHOWS AREAS OF STRATUS AT THE SAME TIME
WHICH WOULD SLOW THE LIFTING PROCESS.
A WEAK AND DECAYING MCS ACROSS NWRN NEB/SWRN SD THIS MORNING IN
COMBINATION WITH A WEAK DISTURBANCE OVER ERN COLO COULD PERHAPS
SPREAD ISOLATED SHOWERS AND THUNDERSTORMS INTO WRN NEB.
THE HRRR THEN SHOWS CONVECTIVE DESTABILIZATION ACROSS SWRN NEB BY
20Z WHICH IS PROBABLY AN HOUR OR TWO TOO FAST. THE MAIN IMPULSE
WOULD APPEAR TO BE DROPPING SOUTHEAST THROUGH NERN WY/WRN SD AT
20Z...STILL HOURS AWAY FROM THE FCST AREA. A MCS IS EXPECTED TO
DEVELOP OUT OF THE STORMS FIRING ACROSS THE NRN HIGH PLAINS WHICH
SHOULD SWEEP THRU NRN NEB OVERNIGHT. THE MCS SHOULD REMAIN MOSTLY
ALONG AND NORTH OF HIGHWAY 20.
TEMPERATURES TODAY ARE EXPECTED TO RISE INTO THE LOW TO MID 80S
IN MOST AREAS GIVEN THE CONTINUED SOUTH AND SOUTHEAST WINDS
CIRCULATING AROUND HIGH PRESSURE CENTERED OVER THE MIDWEST. THE
ENSUING WARM AIR ADVECTION FUELING THE MCS TONIGHT SHOULD KEEP
SKIES MOSTLY CLEAR SOUTH OF THE CONVECTIVE COMPLEX. THE NAM12
HINTS AT A BANK OF STRATUS FILLING IN ACROSS NWRN NEB IN THE WAKE
OF THE MCS AROUND 12Z.
SEVERE WEATHER POTENTIAL WITH THE THUNDERSTORMS THIS AFTERNOON
AND TONIGHT IS LIMITED TO 5 PERCENT OR ISOLATED WITH THE BEST
INSTABILITY AND 40 TO 50 KT 1 TO 6 KM SHEAR ACROSS NRN NEB MOSTLY
ASSOCIATED WITH THE DEVELOPING MCS. MODEL INDICATIONS SUGGEST THE
BLACK HILLS COULD BE THE GENESIS FOR A CLUSTER OF STORMS FORMING
LATE IN THE AFTERNOON WHICH WOULD MOVE EAST SOUTHEAST TOWARD
KVTN-KANW-KONL DURING THE EVENING AND OVERNIGHT. THIS IN TURN
COULD CERTAINLY INCREASE THE SEVERE WEATHER POTENTIAL IN THOSE
AREAS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 400 AM CDT TUE JUL 30 2013
WEDNESDAY MORNING LINGER SHOWERS WILL BE POSSIBLE ACROSS PORTIONS
OF CENTRAL/NORTH CENTRAL NEB. THEN BREAKS IN THE CLOUDS SHOULD
HELP TO PUSH HIGHS INTO THE 80S. LATE IN THE DATE MODELS IN
AGREEMENT WITH A BOUNDARY STRETCHED FROM WEST CENTRAL KS
NORTHEAST INTO CENTRAL NEB AND ON TOWARDS THE WESTERN GREAT
LAKES. THUNDERSTORMS WILL BE POSSIBLE ALONG THE SLOW MOVING
BOUNDARY...HOWEVER IMPACT TO THE CWA IN QUESTIONS. THE LATEST NAM
AND GFS HAVE PUSHED THE BOUNDARY JUST SE OF THE CWA BY PEAK
HEATING...HOWEVER THE EC AND GEM DO DEVELOP ACTIVITY IN THE SE
CWA. WILL TREND DOWN WITH POPS...ALTHOUGH STILL RETAIN SLGHT CHC
IN THE FAR SE ZONES. MORE OF A FOCUS WILL BE THE NEXT SHORT WAVE
CROSSING THE ROCKIES. THIS WAVE SHOULD ALLOW DEVELOPMENT ON THE
HIGHER TERRAIN WITH FLOW TO PUSH THIS INTO THE PANHANDLE AND
WESTERN NEBRASKA OVERNIGHT.
THURSDAY WILL SEE YET ANOTHER SHORT WAVE TO PUSH ACROSS THE AREA.
MODELS CONTINUE TO SHOW GOOD INSTABILITY WITH DECENT SHEAR...ALSO
WILL SEE A SURF LOW DEVELOP NEAR NE CO. ANY ACTIVITY DEVELOPING IN
THE EVENING FROM PEAK HEATING WILL LIKELY BE SUSTAINED BY A 30 TO
40K LL JET. LOW FREEZING LEVEL WITH STEEP LAPSE RATE SHOULD RESULT
IN A FEW STRONG TO EVEN SEVERE STORMS...WITH HAIL THE MAIN THREAT.
FRIDAY WILL SEE AN UPPER LEVEL LOW COME ONSHORE TO THE PAC
NW...THIS WILL FLATTEN THE RIDGE AND PUSH IT EASTWARD. INITIALLY
THOUGHT THERE COULD BE A WARM UP...HOWEVER MODELS CONTINUE TO
BRING GOOD MOISTURE AROUND THE RIDGE...RESULTING IN MORE CLOUDS
THAN SUN. FORECAST RESULTS IN BELOW NORMAL HIGHS...WHICH IS CLOSE
TO MOS GUIDANCE.
LITTLE CHANGES THROUGH THE WEEKEND FOR THE AREA...AS RIDGE REMAINS
TO THE SOUTH AND LOW WILL TRAVERSE ACROSS THE US/CAN BORDER. FLOW
WILL CONTINUE TO BE NORTHWESTERLY TO ZONAL...AND MODELS CONTINUE
TO BRING WAVE AFTER WAVE ACROSS THE AREA. QPF MAY NOT BE
SIGNIFICANT...HOWEVER WILL NEED TO CONTINUE TO MENTION IN NEARLY
EVERY PERIOD PENDING TIMING OF THE WAVES. TEMPS WILL GENERALLY BE
BELOW NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1255 PM CDT TUE JUL 30 2013
HAVE ADDED VCTS IN THE VTN TAF BASED ON THE IDEA OF BETTER
CONVECTIVE COVERAGE ACROSS NC NEBRASKA THIS AFTERNOON AND EVENING.
CONFIDENCE ON COVERAGE FURTHER SOUTH IS NOT AS GOOD AND THEREFORE
LEFT OUT OF THE LBF TAF.
OTHERWISE HAVE GONE WITH MAINLY IFR CONDITIONS THROUGH THE
PERIOD...THOUGH SOME CONCERN ABOUT A REDEVELOPMENT OF LOW CLOUDS
AND/OR FOG AFTER 09Z TONIGHT. THINK BETTER CHANCES FOR THIS WOULD
BE EAST OF VTN TAF SITE SINCE A SHIFT TO A NORTHERLY WIND SHOULD
OCCUR BEFORE ONSET...BUT MAY HAVE TO BE INTRODUCED INTO THE LBF
TAF WITH LATER FCSTS.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JWS
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...JWS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1118 AM CDT TUE JUL 30 2013
.UPDATE...
ISSUED AT 1057 AM CDT TUE JUL 30 2013
ADJUSTED SKY COVER UP FOR THE REMAINDER OF THE MORNING...AND
FOLLOWED CLOSER TO THE HRRR FOR SKY COVER FOR THE REST OF THE DAY
INTO THE NIGHT. THIS MODEL SEEMS TO BE DOING THE BEST HANDLING THE
ERODING WEST SIDE OF THE STROTOCUMULUS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 336 AM CDT TUE JUL 30 2013
AREAS OF FOG HAVE DEVELOPED ACROSS THE REGION OVERNIGHT AS ELEVATED
DEW POINTS AND LIGHT WINDS HAVE AIDED IN ITS FORMATION. AFTER MAKING
A FEW PHONE CALLS AND PERUSING HIGHWAY CAMERAS THE PAST HOUR...HAVE
DECIDED TO GO AHEAD AND EXPAND THE DENSE FOG ADVISORY NORTH AND EAST
WITH THE MORNING FORECAST PACKAGE TO ACCOUNT FOR POCKETS OF DENSE
FOG THAT HAVE FORMED. WHILE MODEL GUIDANCE IS NOT HANDLING THIS FOG
VERY WELL...CANNOT SEE A REASON FOR CONDITIONS TO IMPROVE MUCH
BEFORE SUNRISE...AND WILL KEEP EXPIRATION TIME OF 14Z FOR THE TIME
BEING.
FOR TODAY...ONCE THE FOG BEGINS TO LIFT DURING THE MID MORNING
HOURS...EXPECT A FAIRLY NICE DAY ACROSS THE REGION AS TEMPERATURES
WILL BEGIN TO MODERATE CLOSER TO SEASONAL NORMS...WINDS WILL BE
LIGHT...AND SKIES WILL BEGIN TO CLEAR. WHILE CLOUDY SKIES WILL
ENVELOP THE REGION THROUGH MID MORNING HOURS...EXPECT AT LEAST A
PARTLY SUNNY AFTERNOON AS THE FRONTAL BOUNDARY TO OUR SOUTH...
RESPONSIBLE FOR THE ACTIVE WEATHER ON MONDAY...CONTINUES TO SHIFT
SOUTHEASTWARD.
THEREAFTER THE FOCUS WILL SHIFT NORTHWARD AS SHORTWAVE CROSSING THE
NORTHERN PLAINS...ALONG WITH A SURFACE COLD FRONT...BEGIN TO SAG
SOUTHWARD TOWARDS THE LOCAL AREA. THE LATEST WRF INDICATES A NICE
BAND OF CONVECTION DEVELOPING AHEAD OF THIS WAVE LATE TUESDAY
NIGHT...WHILE THE 06Z NAM/00Z GFS/EC KEEP THE BULK OF THE CONVECTION
NORTH OF THE LOCAL FORECAST AREA. HOWEVER...WITH PLENTY OF ELEVATED
INSTABILITY TO WORK WITH AND SOME SYNOPTIC SCALE FORCING...SIDED
TOWARDS THE MORE AGGRESSIVE SOLUTION OF THE WRF AND INCREASED POPS
ACROSS THE NORTH LATE TUESDAY NIGHT. THAT SAID...KEPT CONVECTION
POTENTIAL GENERALLY NORTH OF I80 DURING THE OVERNIGHT HOURS AS THE
00Z WRF SEEMS TO BE THE OUTLIER TAKING ACTIVITY MUCH FURTHER SOUTH
THAN REMAINDER OF GUIDANCE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 336 AM CDT TUE JUL 30 2013
PRIMARY CONCERN IN THE EXTENDED WILL BE ALMOST DAILY
CHANCES FOR PRECIPITATION. LOOKING AT THE BIG PICTURE...BY
WEDNESDAY MORNING IT APPEARS WE WILL BE IN NORTHWEST FLOW AS MODELS
IN DECENT AGREEMENT IN PLACING A MID LEVEL CUT OFF LOW JUST OFF THE
PACIFIC NORTHWEST COAST...AND ANOTHER ONE OVER WESTERN ONTARIO. IN
BETWEEN THIS IS A DIRTY RIDGE CENTERED OVER THE ROCKIES. THERE
APPEARS TO BE SOME PROGRESSION OF THESE SYSTEMS EASTWARD DURING THE
REST OF THE WORK WEEK...BUT FOR US IT LOOKS LIKE WE COULD HAVE MINOR
SHORTWAVES PASSING THROUGH THE RIDGE. SOME OF THESE MAY PACK A
LITTLE MORE PUNCH AND THE FIRST ONE OF THESE LOOKS TO BE THURSDAY
NIGHT. WILL CONTINUE TO KEEP HIGHEST POPS GOING FOR THURS NIGHT.
BACKING UP JUST A BIT AND CHECKING THE SURFACE FEATURES...IT LOOKS
LIKE THERE WILL BE A WEAK FRONTAL BOUNDARY DROPPING SOUTH ACROSS THE
CWA DURING THE DAYTIME ON WED. THIS COULD HELP TRIGGER THUNDERSTORMS
BY THE AFTERNOON. BY LATE IN THE WEEK AND INTO THE WEEKEND A
FRONTAL BOUNDARY WILL BE SOMEWHERE NEAR THE CWA AND THE INTERACTION
OF PASSING MID LEVEL DISTURBANCES WITH THE SURFACE FEATURE WILL KEEP
OUR WEATHER UNSETTLED.
AS FAR AS SEVERE CHANCES ARE CONCERNED...PROGGED DEEP LAYER SHEAR
LOOKS TO BE IMPRESSIVE...ESPECIALLY FOR THIS TIME OF YEAR...WITH
0-6 KM VALUES OF 20 TO 50 KT NOTED FOR MOST DAYS ON THE LATEST EC
AND/OR GFS RUN. INSTABILITY ALSO IMPRESSIVE WITH MU CAPE NUMBERS
QUITE HIGH. ON THE NEGATIVE SIDE...THERE COULD BE SOME CAPPING
ISSUES ESPECIALLY LATER IN THE WEEK AND INTO THE WEEKEND WITH
PROGGED 700 MB TEMPS EXPECTED TO BE BETWEEN 11 AND 15 DEGREES
CELSIUS..WITH THE GFS A LITTLE WARMER.
&&
.AVIATION...(FOR THE 12Z KGRI TAF THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 550 AM CDT TUE JUL 30 2013
POOR AVIATION CONDITIONS ARE EXPECTED TO PREVAIL AT KGRI FOR THE
NEXT SEVERAL HOURS AS DENSE FOG HAS SET IN ACROSS THE TERMINAL.
PREVAILING VISIBILITIES OF 1SM OR LESS ARE EXPECTED THROUGH
30/14Z...WITH IFR/LIFR CIGS NEAR OR BELOW 500 FT. EXPECT THE
CEILINGS AND VSBYS TO SLOWLY IMPROVE DURING THE LATE MORNING
HOURS...WITH A RETURN TO VFR VSBYS AND MVFR CIGS BY 30/17Z. WINDS
WILL START OFF THE PERIOD LIGHT AND VARIABLE...AND REMAIN LIGHT
AT LESS THAN 8KTS OUT OF THE EAST THROUGH THE REMAINDER OF THE
PERIOD.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HEINLEIN
SHORT TERM...SAR
LONG TERM...EWALD
AVIATION...SAR
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1211 PM CDT TUE JUL 30 2013
.UPDATE...
ISSUED AT 1211 PM CDT TUE JUL 30 2013
LATEST TRENDS PER SATELLITE/RADAR/SPC DATA SHOW THAT THE AREAL
COVERAGE FOR POTENTIAL SEVERE THUNDERSTORM DEVELOPMENT CONTINUES
TO SHRINK...NOW COVERING ONLY FAR SOUTH CENTRAL NORTH DAKOTA.
CURRENT CLOUD CANOPY COVERING MOST OF WESTERN AND CENTRAL NORTH
DAKOTA IS LIMITING LOW LEVEL INSTABILITY TO NIL...AND WHILE UPSTREAM
IMAGERY DOES SHOW SOME BREAKS IN THE CLOUD COVER...IT APPEARS
THAT THE STRONGEST DIVERGENCE FIELD WILL LAY ACROSS SOUTH DAKOTA
THIS AFTERNOON AND EVENING. AT THE SURFACE...PRESSURE RISES ARE
MAXIMIZED IN SOUTHWEST NORTH DAKOTA ALONG WITH A WEAK LOW LEVEL
EAST TO NORTHEAST WIND FIELD. THE LATEST HIGH RESOLUTION MODELS OF
THE RAP AND HRRR CONTINUE TO TREND WITH SEVERE WEATHER THREAT
MAINLY SOUTH OF THE BORDER THIS AFTERNOON...WITH MORE OF A
SCATTERED SHOWER/THUNDERSTORM EVENT WITH AN ISOLATED STRONG TO
POSSIBLY SEVERE THUNDERSTORM EMBEDDED WITHIN THIS AREA ACROSS
WESTERN AND CENTRAL NORTH DAKOTA. WILL CONTINUE TO MONITOR FOR ANY
CHANGES. 12Z NAM/GFS SOUNDINGS CONTINUE TO INDICATE A SKINNY CAPE
FIELD THIS AFTERNOON. ADJUSTED POPS THIS AFTERNOON AND LIMITED THE
SEVERE WEATHER WORDING FAR SOUTH CENTRAL. ALSO LOWERED MAX TEMPS A
COUPLE OF DEGREES...ALLOWING FOR A QUICK RISE WITH ANY BREAKS
FOLLOWED BY CLOUDS QUICKLY FILLING BACK IN AGAIN.
UPDATE ISSUED AT 839 AM CDT TUE JUL 30 2013
LATEST REGIONAL LOCAL/RADAR SHOWS SCATTERED SHOWERS AND
THUNDERSTORMS INTO SOUTHWEST AND PORTIONS OF WESTERN NORTH DAKOTA.
VISIBLE IMAGERY SHOWS A LARGE CLOUD CANOPY ASSOCIATED WITH THE
SOUTHWEST AREA OF THUNDERSTORMS EXTENDING EAST TO NEAR THE
MANDAN/BISMARCK AREA.
STILL NOT REAL CLEAR ON WHAT SCENARIO WILL PLAY OUT TODAY. HIGH
RESOLUTION MODELS HINTING AT THE CURRENT PRECIPITATION IN THE WEST TO
EXPAND AND BECOME THE MAIN SHOW THROUGH MOST OF THE AFTERNOON WITH
LITTLE FURTHER ACTIVITY BY LATE AFTERNOON AND EARLY EVENING. THE
LARGER SCALE MODELS AND WATER VAPOR IMAGERY DEPICT A KEY SHORTWAVE
NOW OVER SOUTHWEST MONTANA TO EJECT EAST INTO WESTERN AND SOUTHWESTERN
NORTH DAKOTA LATER THIS AFTERNOON AND EVENING. THIS SHORTWAVE
COMBINED WITH A JET STREAK IN SOUTHERN CANADA AND A WEAKER ONE IN
SOUTH DAKOTA WOULD BECOME THE MAIN CATALYSTS TO HELP INITIATE
STRONG TO SEVERE THUNDERSTORMS. THE NAM/GFS 06Z SOUNDINGS SHOW
MINIMAL TO NIL CAPE THIS AFTERNOON. AS MENTIONED ABOVE...LARGE
CLOUD SHIELD WILL INHIBIT SURFACE HEATING AND OVERALL LOW LEVEL
DESTABILIZATION. IF THIS CONTINUES WILL HAVE TO AWAIT FOR STRONGER
DYNAMICS WITH THE AFOREMENTIONED SHORTWAVE AND JET STREAKS TO
ENHANCE LIFT AND INITIATE STRONGER CONVECTION TO FORM.
UPDATES TO HOURLY SKY GRIDS PER LATEST VISIBLE IMAGERY. WILL
ADJUST POPS TO MATCH THIS MORNINGS RADAR...BUT UNTIL THE 12Z DATA
COMES IN...WILL LEAVE CURRENT POP/WEATHER SCENARIO ALONE FOR NOW
OTHER THAN CHANGING THE WORDING FROM UNCERTAINTY TO AREAL COVERAGE.
UPDATE ISSUED AT 637 AM CDT TUE JUL 30 2013
UPDATED THE FORECAST TO ADD AREAS OF DENSE FOG OVER PIERCE AND
WELLS COUNTIES BASED ON SURFACE OBS. THINK THESE REDUCED
VISIBILITIES SHOULD IMPROVE DURING THE NEXT FEW HOURS AS VERTICAL
MIXING COMMENCES WITH THE ONSET OF DAYTIME HEATING.
OTHERWISE...THE SEVERE THREAT STILL APPEARS VALID PRIMARILY FOR
AREAS ALONG AND SOUTH OF I-94 THIS AFTERNOON AND EVENING. LARGE
HAIL AND DAMAGING WINDS STILL LOOK TO BE THE PRIMARY THREATS.
THE REMAINING WEATHER ELEMENTS ARE IN GOOD SHAPE. THE UPDATED
GRIDDED AND TEXT PRODUCTS HAVE BEEN SENT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT TUE JUL 30 2013
HAVE NOWCASTED THUNDERSTORMS OUT OF THE FORECAST THROUGH 7 AM CDT
BASED ON AREA DOPPLER RADAR RETURNS. A FEW LOCATIONS...BISMARCK
EARLIER AND HARVEY AND RUGBY AS OF THIS WRITING...HAVE HAD PATCHY
FOG SO WILL KEEP THAT IN THE FORECAST THROUGH 9 AM CDT.
TEMPERATURES WERE IN THE 50S.
FOR TODAY...THE MAIN FORECAST ISSUE IS THUNDERSTORMS AND THE RISK
FOR SEVERE WEATHER. MODELS ARE COMING INTO AGREEMENT THAT THE
RISK OF SEVERE THUNDERSTORMS WILL BE CONFINED TO THE SOUTHWEST AND
SOUTHCENTRAL PARTS OF NORTH DAKOTA. DEW POINTS INTO THE LOWER AND
MID 50S WILL BE INCREASING INTO THE 55 TO 60 DEGREE RANGE ACROSS
THE SOUTH AS MORE MOIST AIR IS ADVECTING IN FROM SOUTH DAKOTA. A
TROUGH AT THE SURFACE...ORIENTED NORTHEAST TO SOUTHWEST THROUGH
THE AREA...WILL BE THE FOCUS FOR LOW PRESSURE IN SOUTHEAST MONTANA
TO RIDE NORTHEAST ON. AT THE SAME TIME A SHORT WAVE TROUGH IN THE
MID ATMOSPHERE WILL BE ADVANCING TOWARD THE STATE AND PROVIDE
LIFTING THROUGH THE MID LEVELS. THE MOISTURE ADVECTION WILL
INCREASE INSTABILITY AND SET THE STAGE FOR STORM DEVELOPMENT.
ADDING TO THIS WILL BE SUFFICIENT SHEAR (BOTH SPEED AND DIRECTION)
TO SUPPORT SUPER CELL FORMATION. STEEP MID LEVEL LAPSE RATES WILL
ADD TO THE STORMS ABILITY TO GROW VERTICALLY INTO THE ATMOSPHERE.
HAVE HIGHLIGHTED THE RISK IN SERVICES FOR TODAY...INCLUDING ON THE
WEB PAGE AND LATER TO SOCIAL MEDIA.
STORMS DECREASE FROM WEST TO EAST THIS EVENING.
HIGH TEMPERATURES TODAY WILL BE CLOSER TO SEASON NORMALS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 400 AM CDT TUE JUL 30 2013
DRY CONDITIONS AND BELOW NORMAL TEMPERATURES ARE EXPECTED TO DEVELOP
AREAWIDE WEDNESDAY AND THURSDAY AS HIGH PRESSURE BUILDS INTO THE
REGION.
PRECIP CHANCES ARE PROGGED TO INCREASE WEST FRIDAY AHEAD OF A
SHORTWAVE OVER THE PACIFIC NORTHWEST. PRECIP CHANCES ARE THEN
EXPECTED TO GRADUALLY SPREAD INTO CENTRAL NORTH DAKOTA LATE SATURDAY
AND CONTINUE THROUGH MONDAY AS THE SHORTWAVE LIFTS INTO THE CANADIAN
PRAIRIES. THE PERSISTENT NORTHWESTERLY FLOW ALOFT SHOULD KEEP
TEMPERATURES BELOW NORMAL THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1211 PM CDT TUE JUL 30 2013
A VCTS COVERS ALL AERODROMES THROUGH THE EVENING AS SCATTERED
SHOWERS AND THUNDERSTORMS WILL CONTINUE TO DEVELOP...BUT TIMING
AND COVERAGE OF THE PRECIPITATION IS NOT EXACT. WILL MONITOR RADAR AND
AMEND AS NECESSARY TO CAPTURE ANY CRITICAL CIG/VSBY REDUCTION DUE
TO THE SHOWERS/THUNDERSTORMS. EXPECT VFR CIGS/VSBYS OUTSIDE ANY
THUNDERSTORMS WITH A BRIEF PERIOD OF MVFR/IFR CIGS/VSBYS POSSIBLE
WITH ANY OF THE STRONGER THUNDERSTORMS. THE PRECIPITATION WILL
DIMINISH BY 06Z WITH CLEARING SKIES AND VFR CIGS FORECAST FOR
WEDNESDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...JPM
LONG TERM...TM
AVIATION...KS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
215 PM CDT TUE JUL 30 2013
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 215 PM CDT TUE JUL 30 2013
CURRENTLY AS OF 19Z...
WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED SUBTROPICAL
RIDGING OVER THE SOUTHWESTERN U.S....TROUGHING OVER SASKATCHEWAN AND
MANITOBA...AND WEST-NORTHWEST FLOW FROM MONTANA INTO THE FORECAST
AREA. WITHIN THE FLOW...A FEW SHORTWAVES WERE CROSSING NORTH DAKOTA.
CONDITIONS ARE DRY ACROSS THE FORECAST AREA...BUT PLENTY OF STRATUS
OF THE LOW TO MID LEVEL VARIETY EXISTS. THESE CLOUDS HAVE HELD
TEMPERATURES DOWN SOMEWHAT...BUT ENOUGH SUN HAS MADE IT THROUGH WITH
THE 850MB TEMPS BETWEEN 11-13C PER 12Z RAOBS TO BRING READINGS INTO
THE 70S. TO THE WEST...A COLD FRONT WAS PRESENT OVER FAR WESTERN
MN...JUST AHEAD OF THE SHORTWAVES. THE COLD FRONT SO FAR HAS NOT
DONE ANYTHING PRECIPITATION WISE...BUT THERE HAS BEEN CONVECTION
BEHIND THE FRONT OVER SOUTHERN SOUTH DAKOTA.
SYNOPTIC OVERVIEW...
MODELS ARE IN VERY GOOD AGREEMENT DROPPING A PORTION OF THE
TROUGHING OVER SOUTH CENTRAL CANADA THROUGH THE FORECAST AREA
WEDNESDAY AFTERNOON. THIS PORTION OF THE TROUGH...OR SHORTWAVE...IS
OF MOST CONCERN...SINCE IT WILL PUSH THE COLD FRONT TO OUR WEST
ACROSS THE FORECAST AREA. IT APPEARS THE SHORTWAVES CURRENTLY ACROSS
NORTH DAKOTA WILL HEAD EAST TOWARDS UPPER MI.
HAZARDS...
SOME SEVERE WEATHER POTENTIAL WEDNESDAY AFTERNOON GIVEN 0-6 KM SHEAR
VALUES AROUND 40 KT PRESENT WITH A FRONTAL PASSAGE. HOWEVER...THERE
ARE SERIOUS CONCERNS ON AVAILABLE INSTABILITY AS DESCRIBED IN THE
DETAILS BELOW. SHOULD SEVERE WEATHER OCCUR...HAIL WILL BE THE MAIN
CONCERN.
DETAILS...
A LIGHT SOUTHERLY FLOW AHEAD OF THE WESTERN MN COLD FRONT WILL ALLOW
SOME OF THE LOWER CEILING STRATUS AND FOG THAT HAS PRESENT JUST
SOUTH OF THE FORECAST AREA TO COME UP INTO NORTHEAST IOWA AND FAR
SOUTHWEST WISCONSIN TONIGHT. HAVE ADDED SOME FOG MENTION TO THESE
LOCATIONS. OTHERWISE...TONIGHT LOOKS FAIRLY QUIET WITH BASICALLY NO
ISENTROPIC LIFT AND ALL SHORTWAVE FORCING HEADING UP TO THE NORTH.
ONE ITEM OF INTEREST PRESENT IN SOME PAST HRRR RUNS AS WELL AS THE
30.12Z ECMWF AND HIRES-ARW IS A BAND OF SHOWERS FROM NEAR WABASHA
COUNTY TO TAYLOR COUNTY BETWEEN 00-09Z. GIVEN THE 30.17Z HRRR RUN IS
DRY AND AFOREMENTIONED FORCING SIGNALS ARE WEAK TO NONE...HAVE KEPT
THE FORECAST DRY IN THIS AREA. A MIX OF LOW AND HIGHER STRATUS
SHOULD PERSIST THROUGH MUCH OF THE NIGHT...HELPING TO KEEP
TEMPERATURES UP.
ON WEDNESDAY...THE NEXT SHORTWAVE OF FOCUS DROPPING OUT OF SOUTH
CENTRAL CANADA WILL PROVIDE A PERIOD OF DPVA ACROSS THE FORECAST
AREA...ALONG WITH GIVING THE COLD FRONT OVER FAR WESTERN MN A BIGGER
PUSH. THE BIG QUESTIONS ARE BOTH FRONTAL TIMING AND HOW WARM CAN WE
GET PRIOR TO FRONTAL ARRIVAL. ALTHOUGH THERE IS NOW LESS CONCERN
FOR LOW CEILING STRATUS OVER ABOUT THE NORTHWEST 2/3 OF THE FORECAST
AREA...ISENTROPIC LIFT FIELDS SUGGEST A GOOD AMOUNT OF MID/HIGH
CLOUDS WILL OVERSPREAD THE AREA AHEAD OF THE SHORTWAVE AND COLD
FRONT. THE 30.12Z NAM EVEN DEVELOPS SOME LIGHT PRECIPITATION OUT OF
THESE CLOUDS NORTH OF I-90. MAIN COLD FRONTAL TIMING STILL LOOKS TO
BE DURING THE AFTERNOON WHICH IS GOOD...BUT THE AFOREMENTIONED
CLOUDS MAY LIMIT HEATING AND THUS BOTH CAPE AND CONVECTIVE
DEVELOPMENT ON THE FRONT. MODEL CONSENSUS IS TO GET HIGH
TEMPERATURES PRIOR TO FRONTAL ARRIVAL UP INTO THE MID 70S TO AROUND
80...WHICH RESULTS IN ABOUT 500-1000 J/KG OF TALL...THIN CAPE. THE
SKINNY NATURE OF THE CAPE WILL HELP MINIMIZE THE SEVERE WEATHER
POTENTIAL DESPITE FAVORABLE SHEAR.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 215 PM CDT TUE JUL 30 2013
SYNOPTIC OVERVIEW...
30.12Z ECMWF/GFS/CANADIAN ALL SUGGEST A REX BLOCK STAYING MOSTLY IN
PLACE OVER WESTERN CANADA INTO THE GULF OF ALASKA...ALONG WITH
TROUGHING OVER SOUTHEAST CANADA INTO THE GREAT LAKES
REGION...THROUGH THE LONG TERM PERIOD. THIS MEANS THE FORECAST AREA
WILL STAY IN COOL...NORTHWEST FLOW WITH SHORTWAVES COMING THROUGH
THAT CAN BE HARD TO TIME. WHETHER OR NOT THESE SHORTWAVES PRODUCE
PRECIPITATION WILL DEPEND ON MOISTURE AVAILABILITY.
WEDNESDAY NIGHT THROUGH FRIDAY...
IN THE WAKE OF WEDNESDAYS COLD FRONTAL PASSAGE...THE 30.12Z NAM
BRINGS SOME PRECIP THROUGH THE SOUTHWESTERN HALF OF THE FORECAST
AREA WEDNESDAY NIGHT. THIS IS A RESULT OF SOME WEAK 305K ISENTROPIC
LIFT AHEAD OF A WEAK SHORTWAVE TRAVERSING IOWA...AS WELL AS BEING IN
THE LEFT EXIT REGION OF A 100 KT JET STREAK. ALL OTHER AVAILABLE
GUIDANCE IS DRY...CONSISTENT TOO WITH THE PREVIOUS FORECAST.
THEREFORE...HAVE KEPT A DRY FORECAST GOING. MODELS HAVE TRENDED
DRIER ON THURSDAY WITH ANY CONVECTIVE FORCING WELL OFF TO OUR NORTH
OR SOUTHWEST. ADDITIONALLY...IT APPEARS THERE SHOULD BE A SURGE OF
DRY AIR ON THURSDAY TO HELP MIX DEWPOINTS DOWN...ALSO FAVORING A
DRIER FORECAST. THURSDAY NIGHT INTO FRIDAY MAY STAND TO HAVE THE
BEST CHANCE FOR PRECIPITATION IN THIS NORTHWEST FLOW...IF YOU
BELIEVE THE NAM. MODELS ARE IN GOOD AGREEMENT DROPPING A SHORTWAVE
THROUGH NORTHERN WI FRIDAY MORNING. THE NAM IS MOST ROBUST IN
GENERATING BOTH LIFT AND QPF FROM THIS SHORTWAVE. HOWEVER...THE
GFS/ECMWF/CANADIAN ARE ALL MUCH DRIER AND SOME EVEN SUGGEST A DRY
FORECAST. THEREFORE...CONFIDENCE IN THE NAM SCENARIO IS QUITE LOW.
DID MAINTAIN A 20 PERCENT CHANCE FOR LATE THURSDAY NIGHT ACROSS THE
FORECAST AREA...AS WELL AS SOUTH OF I-90 ON FRIDAY...IN THE EVENT
THE NAM IS RIGHT. WITH 850MB TEMP ANOMALIES HOVERING IN THAT 0.5-1
STANDARD DEVIATION BELOW NORMAL...TEMPERATURES SHOULD CONTINUE TO
RUN ABOUT 5F DEGREES BELOW NORMAL FOR HIGHS. GENERALLY FOLLOWED A
MODEL GUIDANCE CONSENSUS FOR BOTH HIGHS AND LOWS.
FRIDAY NIGHT THROUGH TUESDAY...
DESPITE A NORTHWEST FLOW DURING THE WEEKEND...CONFIDENCE OF HAVING
IT DRY IS INCREASING. THE REASON IS THAT MODELS HAVE BEEN
CONSISTENTLY SHOWING CANADIAN HIGH PRESSURE BUILDING INTO THE
FORECAST AREA IN THE WAKE OF THAT SHORTWAVE CROSSING NORTHERN WI
FRIDAY MORNING. GIVEN THE CANADIAN SOURCE REGION...THE WEEKEND DOES
LOOK COOL...BUT NOT NEARLY AS COLD AS LAST WEEKEND. 850MB TEMPS DROP
TO 10-12C ON SATURDAY AND 8-11C ON SUNDAY WHICH AT MOST ARE 1-1.5
STANDARD DEVIATIONS BELOW NORMAL. THESE TEMPS STILL SUPPORT HIGHS IN
THE 70S. THE BIGGER QUESTION WILL BE LOWS...WHICH HIGHLY DEPENDS ON
TIMING WHEN THE SURFACE HIGH BUILDS OVERHEAD FOR PRIME RADIATIONAL
COOLING CONDITIONS. LOWS IN THE TYPICAL COLDER SPOTS IN THE 40S ARE
CERTAINLY POSSIBLE.
HEADING INTO EARLY NEXT WEEK...THERE ARE SIGNS IN THE 30.12Z
ECMWF/GFS OF A MORE SIGNIFICANT SHORTWAVE DROPPING THROUGH THE
NORTHWEST FLOW...COMING THROUGH THE FORECAST AREA ON MONDAY. THIS IS
A BIT OF A CHANGE FOR THE ECMWF...BEGINNING TO LEAN MORE TOWARDS
WHAT THE PAST FEW GFS RUNS HAVE SUGGESTED. IN ANY EVENT...CHANCES OF
SHOWERS AND THUNDERSTORMS ARE REQUIRED FOR SUNDAY NIGHT AND MONDAY
TO ACCOUNT FOR THE SHORTWAVE AND ASSOCIATED FORCING. FOR MONDAY
NIGHT AND TUESDAY...CONTINUITY AND MODEL CONSENSUS SUGGESTS HOLDING
ONTO 20-30 PERCENT CHANCES DURING THIS TIME PERIOD. THESE CHANCES
ARE ASSOCIATED WITH THE AFOREMENTIONED SHORTWAVE. HOWEVER...NEW
30.12Z GUIDANCE...PARTICULARLY THE ECMWF...SUGGESTING THAT A DRIER
FORECAST MAY BE MORE CORRECT. GIVEN THE UNCERTAINTY BEING IN
NORTHWEST FLOW AND HOW FAR OUT TUESDAY IS IN THE FORECAST...HAVE
LEFT THE CHANCES ALONE FOR NOW. 850MB TEMPS REMAIN BELOW
NORMAL...BETWEEN 10-12C...KEEPING HIGHS IN THE 70S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 12Z WEDNESDAY AFTERNOON)
ISSUED AT 1210 PM CDT TUE JUL 30 2013
MASS OF LOW STRATUS COUPLED WITH FOG REDUCING VSBYS BELOW 1SM WERE
FOUND ACROSS NEB EARLY THIS MORNING. THE CLOUDS WERE EXPERIENCING
SOME DIURNAL BUMP UP...BUT STILL IN THE IFR/MVFR RANGE. THE
EXPECTATION IS THAT THIS STRATUS DECK WILL MOVE ACROSS THE TAF SITES
LATER TODAY...WITH A SUBSEQUENT DROP IN VSBYS THROUGH THE NIGHT
TIME HOURS. LIFR/IFR WOULD RESULT IF NEB/S MORNING CONDITIONS ARE
REALIZED HERE. CONFIDENCE IN THIS OCCURING IS SHAKY THOUGH. LATEST
BUFKIT SOUNDINGS VIA RAP/NAM/GFS AREN/T OVERLY SATURATED IN THE
LOWEST LAYERS...BUT DO SUGGEST THAT IT COULD HAPPEN. FEEL MORE
CONFIDENT WITH THE POTENTIAL TO THE SOUTH. ITS AN ADVECTIVE TYPE OF
FOG/STRATUS THOUGH...AND WILL STAY WITH THE TREND OF BRINGING IT IN
FOR NOW. TRENDS WILL HAVE TO BE MONITORED CLOSELY...AND UPDATES MADE
AS NEEDED.
ASSUMING THE STRATUS/FOG DOES MOVE IN...SOUNDINGS WOULD MIX IT OUT
BY MID/LATE MORNING. A PRE-FRONTAL TROUGH MOVES IN FROM THE WEST
SOMEWHERE IN THE 12-15Z TIME FRAME...WITH THE FRONT DROPPING THROUGH
IN THE AFTERNOON. THE FRONT SHOULD SPARK SCATTERED -SHRA/TS AROUND
IT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION.....RIECK