Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/28/13
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
840 AM PDT WED JUN 26 2013
...MUCH WARMER WEATHER ON THE WAY...
.DISCUSSION...AS OF 08:40 AM PDT WEDNESDAY...HUMID AIR PERSISTS
OVER THE REGION WITH DEWPOINTS IN THE SIXTIES THIS MORNING. A
THIN LAYER OF PATCHY FOG IS AFFECTING PORTIONS OF THE COAST AND
NORTH BAY WITH VISIBILITIES AS LOW AS A QUARTER MILE IN SPOTS.
EXPECT FOG TO BURN OFF BY MID MORNING AND DAYTIME HIGHS TO RUN
FIVE TO TEN DEGREES ABOVE YESTERDAY. MODEL OUTPUT SO FAR THIS
MORNING CONTINUES TO INDICATE PROLONGED WARMING TREND. FORECAST ON
TRACK AND NO UPDATES NECESSARY AT THIS TIME.
&&
.PREV DISCUSSION...AS OF 3:00 AM PDT WEDNESDAY...OVERNIGHT RAIN
ENDED ACROSS OUR CWA AFTER DROPPING A WIDE RANGE OF AMOUNTS FOR
SUNDAY NIGHT TO TUESDAY NIGHT. VALUES RANGED FROM LESS THAN A
TENTH FOR MOST OF THE SOUTHERN CWA ALL OF THE WAY UP TO OVER 5
INCHES FOR SPOTS IN THE NORTH BAY. STILL PLENTY OF MOIST AIR IN
PLACE WHICH IS HELPING TO KEEP DEW POINTS AT HIGH LEVELS EARLY
THIS MORNING ALONG WITH SOME PATCHY FOG NOW BEING INDICATED BY THE
SATELLITE FOG PRODUCT. SURFACE OBS ARE ALSO STARING TO INDICATE A
FEW POCKETS OF REDUCED VISIBILITIES AND THIS SHOULD CONTINUE TO
INCREASE THROUGH THE FIRST HALF OF THE MORNING.
MAIN STORY FOR THE REST OF THE WEEK THROUGH MOST OF NEXT WEEK WILL BE
THE MUCH WARMER WEATHER THAT WILL RETURN TO THE ENTIRE REGION AS A
RIDGE OF HIGH PRESSURE BUILDS TO MUCH OF THE WEST. CONFIDENCE IS
VERY HIGH THAT VERY WARM TO HOT WEATHER WILL RETURN TO INLAND
SPOTS AS 850 MB TEMPS RISE TO AROUND 30C WHILE 500 MB HEIGHT GET
CLOSE TO 600 DM (MOST LIKELY 596-598 DM AROUND HERE). BOTH OF
THESE VALUES ALONG WITH THE GENERAL PATTERN SUGGEST SOME HIGHS
(PLUS EVEN A FEW OVERNIGHT LOWS) WILL APPROACH RECORD VALUES. WHAT
IS NOT ENTIRE CLEAR IS IF WE ARE LOOKING AT A WIDESPREAD HEAT
WARNING EVENT OR JUST VERY WARM READINGS. WHAT IS INTERESTING TO
NOTE IS THE NEW ECMWF HAS 850 MB TEMPS CLOSET TO 28-30C WHILE THE
GFS IS NOW MORE IN THE 30-32C RANGE. CLOSER TO THE COAST...THERE
IS UNCERTAINTY IF THE HEAT WILL PUSH ALL OF THE WAY TO THE OCEAN
OR IF THE THERMAL TROUGH WILL NOT BE ABLE TO MAKE IT THAT FAR.
ALSO WORTH POINTING OUT THAT THE TEMPERATURE ANOMALIES ARE ONLY
EXPECTED TO BE 2 TO 3 ABOVE NORMAL -- STILL IMPRESSIVE, HOWEVER
SHORT OF NUMBERS THAT WE LIKE TO SEE FOR A MAJOR EVENT.
OVERNIGHT LOWS WILL ALSO BE OF NOTE FROM THE EVENT WITH MANY
HIGHER ELEVATION LOCATIONS STRUGGLING TO COOL OUT OF THE 70S (SOME
SPOTS MAY STAY IN THE LOWER 80S AT NIGHT). MANY URBAN SPOTS WILL
LIKELY STAY IN THE 60S. AFTER LOOKING AT THE VARIOUS SOLUTIONS,
DECIDED TO BOOST SOME OF THE HIGHS (ESPECIALLY NEAR THE COAST) AND
LOWS FOR HIGHER ELEVATION SPOTS PLUS PARTS OF THE SANTA CLARA
VALLEY.
CPC KEEPS THE WARMER THAN NORMAL WEATHER CONTINUING OUT FOR THE
6-10 AND 8-14 DAY PERIODS WITH AN ABOVE NORMAL CONFIDENCE LEVEL.
THAT WOULD TAKE US OUT TO JULY 9TH.
&&
.AVIATION...AS OF 4:35 AM PDT WEDNESDAY...UPPER LEVEL HIGH
PRESSURE WILL CONTINUE TO BUILD OVER THE REGION THROUGH THE
FORECAST. ABUNDANT STRATUS OFFSHORE AND HIGH SURFACE MOISTURE (DUE
TO THE RAIN SHOWERS OVER THE PAST FEW DAYS) WILL MAKE FOR A
DIFFICULT FORECAST THROUGH AT LEAST THE EARLY AFTERNOON HOURS.
POSSIBLE REDUCED VISIBILITIES MAY IMPACT THE TERMINALS THROUGH THE
EARLY MORNING HOURS. OTHERWISE...MODERATE WEST WINDS WILL BE
PRESENT ACROSS THE AREA THIS AFTERNOON THROUGH THE EARLY EVENING
HOURS.
VICINITY OF KSFO...POSSIBLE IFR CIGS THROUGH 16Z. VERY LOW
CONFIDENCE. VFR CONDITIONS WILL BE POSSIBLE AFTER
19Z...HOWEVER...A FEW OF THE SHORT TERM MODELS INDICATE CLEARING A
FEW HOURS LATER...CLOSER TO 21Z. MODERATE ONSHORE TO 15 KT THIS
AFTERNOON.
KSFO BRIDGE APPROACH...PATCHY LOW CLOUDS MAY IMPACT THE APPROACH
AN HOUR LATER THAN THE TERMINAL. LOW CONFIDENCE.
MONTEREY BAY AREA TERMINALS...POSSIBLE VLIFR CIGS AND VIS POSSIBLE
THROUGH THE EARLY MORNING HOURS. THE HRRR AND LOCAL WRF INDICATE
THAT KMRY COULD SEE LOW CLOUDS ALL DAY...ADDING TO THE UNCERTAINTY
OF THE FORECAST. OTHERWISE...MODERATE ONSHORE THIS AFTERNOON WITH
AN EARLY RETURN OF STRATUS THIS EVENING.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...NONE.
$$
PUBLIC FORECAST: AC/BELL
AVIATION/MARINE: RILEY
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.SANFRANCISCOBAYAREA.GOV
WWW.TWITTER.COM/NWSBAYAREA
WWW.YOUTUBE.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
439 AM PDT WED JUN 26 2013
...MUCH WARMER WEATHER ON THE WAY...
.DISCUSSION...AS OF 3:00 AM PDT WEDNESDAY...OVERNIGHT RAIN ENDED
ACROSS OUR CWA AFTER DROPPING A WIDE RANGE OF AMOUNTS FOR SUNDAY
NIGHT TO TUESDAY NIGHT. VALUES RANGED FROM LESS THAN A TENTH FOR
MOST OF THE SOUTHERN CWA ALL OF THE WAY UP TO OVER 5 INCHES FOR
SPOTS IN THE NORTH BAY. STILL PLENTY OF MOIST AIR IN PLACE WHICH
IS HELPING TO KEEP DEW POINTS AT HIGH LEVELS EARLY THIS MORNING
ALONG WITH SOME PATCHY FOG NOW BEING INDICATED BY THE SATELLITE
FOG PRODUCT. SURFACE OBS ARE ALSO STARING TO INDICATE A FEW
POCKETS OF REDUCED VISIBILITIES AND THIS SHOULD CONTINUE TO
INCREASE THROUGH THE FIRST HALF OF THE MORNING.
MAIN STORY FOR THE REST OF THE WEEK THROUGH MOST OF NEXT WEEK WILL BE
THE MUCH WARMER WEATHER THAT WILL RETURN TO THE ENTIRE REGION AS A
RIDGE OF HIGH PRESSURE BUILDS TO MUCH OF THE WEST. CONFIDENCE IS
VERY HIGH THAT VERY WARM TO HOT WEATHER WILL RETURN TO INLAND
SPOTS AS 850 MB TEMPS RISE TO AROUND 30C WHILE 500 MB HEIGHT GET
CLOSE TO 600 DM (MOST LIKELY 596-598 DM AROUND HERE). BOTH OF
THESE VALUES ALONG WITH THE GENERAL PATTERN SUGGEST SOME HIGHS
(PLUS EVEN A FEW OVERNIGHT LOWS) WILL APPROACH RECORD VALUES. WHAT
IS NOT ENTIRE CLEAR IS IF WE ARE LOOKING AT A WIDESPREAD HEAT
WARNING EVENT OR JUST VERY WARM READINGS. WHAT IS INTERESTING TO
NOTE IS THE NEW ECMWF HAS 850 MB TEMPS CLOSET TO 28-30C WHILE THE
GFS IS NOW MORE IN THE 30-32C RANGE. CLOSER TO THE COAST...THERE
IS UNCERTAINTY IF THE HEAT WILL PUSH ALL OF THE WAY TO THE OCEAN
OR IF THE THERMAL TROUGH WILL NOT BE ABLE TO MAKE IT THAT FAR.
ALSO WORTH POINTING OUT THAT THE TEMPERATURE ANOMALIES ARE ONLY
EXPECTED TO BE 2 TO 3 ABOVE NORMAL -- STILL IMPRESSIVE, HOWEVER
SHORT OF NUMBERS THAT WE LIKE TO SEE FOR A MAJOR EVENT.
OVERNIGHT LOWS WILL ALSO BE OF NOTE FROM THE EVENT WITH MANY
HIGHER ELEVATION LOCATIONS STRUGGLING TO COOL OUT OF THE 70S (SOME
SPOTS MAY STAY IN THE LOWER 80S AT NIGHT). MANY URBAN SPOTS WILL
LIKELY STAY IN THE 60S. AFTER LOOKING AT THE VARIOUS SOLUTIONS,
DECIDED TO BOOST SOME OF THE HIGHS (ESPECIALLY NEAR THE COAST) AND
LOWS FOR HIGHER ELEVATION SPOTS PLUS PARTS OF THE SANTA CLARA
VALLEY.
CPC KEEPS THE WARMER THAN NORMAL WEATHER CONTINUING OUT FOR THE
6-10 AND 8-14 DAY PERIODS WITH AN ABOVE NORMAL CONFIDENCE LEVEL.
THAT WOULD TAKE US OUT TO JULY 9TH.
&&
.AVIATION...AS OF 4:35 AM PDT WEDNESDAY...UPPER LEVEL HIGH
PRESSURE WILL CONTINUE TO BUILD OVER THE REGION THROUGH THE
FORECAST. ABUNDANT STRATUS OFFSHORE AND HIGH SURFACE MOISTURE (DUE
TO THE RAIN SHOWERS OVER THE PAST FEW DAYS) WILL MAKE FOR A
DIFFICULT FORECAST THROUGH AT LEAST THE EARLY AFTERNOON HOURS.
POSSIBLE REDUCED VISIBILITIES MAY IMPACT THE TERMINALS THROUGH THE
EARLY MORNING HOURS. OTHERWISE...MODERATE WEST WINDS WILL BE
PRESENT ACROSS THE AREA THIS AFTERNOON THROUGH THE EARLY EVENING
HOURS.
VICINITY OF KSFO...POSSIBLE IFR CIGS THROUGH 16Z. VERY LOW
CONFIDENCE. VFR CONDITIONS WILL BE POSSIBLE AFTER
19Z...HOWEVER...A FEW OF THE SHORT TERM MODELS INDICATE CLEARING A
FEW HOURS LATER...CLOSER TO 21Z. MODERATE ONSHORE TO 15 KT THIS
AFTERNOON.
KSFO BRIDGE APPROACH...PATCHY LOW CLOUDS MAY IMPACT THE APPROACH
AN HOUR LATER THAN THE TERMINAL. LOW CONFIDENCE.
MONTEREY BAY AREA TERMINALS...POSSIBLE VLIFR CIGS AND VIS POSSIBLE
THROUGH THE EARLY MORNING HOURS. THE HRRR AND LOCAL WRF INDICATE
THAT KMRY COULD SEE LOW CLOUDS ALL DAY...ADDING TO THE UNCERTAINTY
OF THE FORECAST. OTHERWISE...MODERATE ONSHORE THIS AFTERNOON WITH
AN EARLY RETURN OF STRATUS THIS EVENING.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...NONE.
$$
PUBLIC FORECAST: BELL
AVIATION/MARINE: RILEY
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.SANFRANCISCOBAYAREA.GOV
WWW.TWITTER.COM/NWSBAYAREA
WWW.YOUTUBE.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1117 PM EDT THU JUN 27 2013
.SYNOPSIS...
SURFACE LOW PRESSURE ACROSS EASTERN PENNSYLVANIA WILL MOVE SLOWLY
NORTH THROUGH EASTERN NEW YORK TONIGHT INTO FRIDAY. A SERIES OF
LOW PRESSURE SYSTEMS WILL THEN IMPACT THE REGION THROUGH THE
WEEKEND AND INTO EARLY NEXT WEEK. BERMUDA HIGH PRESSURE
STRENGTHENS AND BUILDS BACK TOWARD THE EASTERN SEABOARD BY THE
MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
TSTMS WILL CONTINUE TO HEAD NORTH THROUGH THE FORKS AND SE CT OVER
THE NEXT COUPE OF HOURS. WARM FRONT NOW ALONG THE CT COAST.
00Z KOKX SOUNDING CAME IN WITH A PW OF 1.73 INCHES. THIS WAS A
TENTH BLW THE 12Z SOUNDING...BUT STILL INDICATIVE OF AN AIRMASS
CAPABLE OF TORRENTIAL DOWNPOURS. THE FFA REMAINS IN EFFECT.
HIGHEST FLOOD THREAT BASED ON THE RR QUAD OF THE H2 JET STILL
LOOKS TO FAVOR THE WRN HALF OF THE CWA.
SLY FLOW IN THE WARM SECTOR BEHIND THE FRONT COULD PRODUCE
ADDITIONAL LLVL SHEAR AS THE FLOW INTERACTS WITH LAND. THIS SHOULD
RESULT IN ISOLD SVR THREAT THRU THE NGT...ESPECIALLY THE S COASTS.
00Z HPC QPF WITH MANUAL ADJUSTMENTS UPWARD THRU 6Z USED IN THE
GRIDS.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
THE GREAT LAKES UPPER LOW CONTINUES TO DEEPEN INTO THE NORTHEAST
DURING THIS TIME PERIOD.
DRYING CONDITIONS ARE LIKELY FRIDAY MORNING ACROSS WESTERN SECTIONS
IN THE WAKE OF THE SHORTWAVE...WITH PARTIAL CLEARING. FAR EASTERN
SECTIONS WILL LIKELY SEE MORE IN THE WAY OF CLOUD COVER...AS THEY
WILL BE ON THE FRINGE OF THE TROPICAL CONVEYOR BELT.
TIMING OF SHORTWAVES AROUND THE UPPER LOW WILL DETERMINE EXACT
TIMING OF ADDITIONAL SHRA/TSRA ACTIVITY FRI AFT/FRI NIGHT...BUT
HIGHEST PROBABILITY WILL LIKELY BE ACROSS INTERIOR FRI AFT/EVE WITH
DIURNAL HEATING.
FLASH FLOOD THREAT APPEARS TO BE LOWER ON FRIDAY AS PWATS DROP TO
1.25 TO 1.5 INCHES IN THE WAKE OF THE SHORTWAVE. MARGINAL
INSTABILITY AND SHEAR ALSO INDICATE THAT STRONG TO SEVERE STORMS
WOULD BE ISOLATED...BUT THIS WILL ULTIMATELY BE DETERMINED BY
STRENGTH OF THE NEXT SHORTWAVE AND AMOUNT OF HEATING.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
UNSETTLED...MUGGY AND WARM CONDITIONS WILL BE THE RULE FOR MUCH OF
THE PERIOD AS AN UPPER TROF OVER THE NE AND OH VALLEY STATES THIS
WEEKEND CLOSES OFF AND RETROGRADES TOWARD THE MID SECTION OF THE
COUNTRY BY THE MIDDLE OF NEXT WEEK. THE AIRMASS WILL BECOME LOADED
WITH MOISTURE AS A DEEP-LAYERED S/SW FLOW BECOMES ESTABLISHED
BETWEEN THE RIDGE OVER THE WESTERN ATLANTIC AND THE UPPER TROF. THE
BEST CHANCE FOR ORGANIZED HEAVY RAINFALL WILL BE ON SUNDAY AS LOW
PRESSURE OVER THE TN AND OH VALLEYS LIFTS NORTH...SENDING A
STATIONARY FRONT JUST SOUTH AND EAST OF THE AREA NORTHWARD AS A WARM
FRONT. PW VALUES WILL BE AROUND 2 INCHES. THIS LOOKS TO BE A MAINLY
HEAVY RAINFALL EVENT AS WIND SHEAR IS MARGINAL AND THE AIRMASS IS
WARM ALOFT. SCT STRONG AND/OR SEVERE CONVECTION IS A POSSIBILITY SAT
AFT/EVE...PRIMARILY NORTH AND WEST OF NYC...WHERE DEEP-LAYERED SHEAR
WILL EXIST WITH THE RRQ OF THE UPPER JET LIFTING ACROSS THE HUDSON
VALLEY. A LIMITING FACTOR ON SAT WILL BE A BRIEF DRYING OUT OF THE
AIRMASS.
EARLY NEXT WEEK...WITH THE FRONTAL BOUNDARY NORTH OF THE REGION AND
THE AREA IN WARM SECTOR...CONVECTION LOOKS TO BE MAINLY DIURNAL IN
NATURE. MON MAY STILL REMAIN WET AS MODEL SOLUTIONS DIVERGE WITH
THE LOCATION OF THE BOUNDARY. THE 12Z ECMWF IS ACTUALLY WETTER ON
MON THAN SUN...A COMPLETE OPPOSITE OF THE GFS...BUT THIS IS DUE TO A
SLOWER TIMING OF THE FRONTAL WAVE.
KEEP IN MIND AN AIRMASS THIS MOIST AND UNSTABLE WILL TRIGGER
ISOLATED TO SCT CONVECTION ALMOST ANYTIME AND IT WILL NOT TAKE MUCH
FOR SOME ORGANIZATION OF CLUSTERS TO FORM POCKETS OF HEAVY RAINFALL.
THIS IS ESPECIALLY THE CASE SUN INTO MON.
AS FOR TEMPS...LOOKING AT BOTH HIGHS AND LOWS RUNNING A FEW DEGREES
ABOVE NORMAL. SHOULD THE AMOUNT OF CLOUD COVER FROM CONVECTION BE
LESS...DAYTIME HIGHS COULD BE SEVERAL DEGREES WARMER THAN CURRENTLY
FORECAST. GENERALLY LOOKING FOR HIGHS 80 TO 85...AND LOWS IN THE
UPPER 60S TO LOWER 70S.
&&
.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
LOW PRESSURE PASSES TO THE WEST TONIGHT AS IT DRIFTS NORTH. AN
ASSOCIATED FRONTAL BOUNDARY STALLS OVER THE AREA ON FRIDAY.
TSTMS NOW ONLY FOR KGON UNTIL AROUND MIDNIGHT. MVFR TO IFR
OVERNIGHT WITH STILL SOME SHRA POSSIBLE...BUT NOT HIGH ENOUGH
CHANCE TO INCLUDE IN TAFS.
S-SE WINDS AROUND 15KT GUSTING TO 20-25 KT IN THE CITY UNTIL
SHORTLY AFTER MIDNIGHT...BCMG S-SW 10-15KT OVERNIGHT. OCCASIONAL
GUSTS TO 20 KT STILL POSSIBLE UNTIL AROUND 07Z.
FOR FRIDAY...SCT SHRA AND TSTMS. BETTER OVERALL CHANCES IN THE AFTN.
VFR AND SW GUSTS AROUND 20 KT DEVELOPING BY AROUND NOON.
.OUTLOOK FOR 00Z SAT THROUGH TUESDAY...
.FRI-TUE...SUB VFR POSSIBLE AT TIMES WITH PERIODS OF SHOWERS
AND TSTMS.
&&
.MARINE...
DENSE FOG ADVY ISSUED FOR THE ERN WATERS THRU TNGT.
OTHERWISE...SCA ON THE OCEAN WITH BUILDING SEAS THRU FRI.
S/SW FLOW CONTINUES THROUGH FRIDAY NIGHT...BUT WINDS ARE EXPECTED TO
BE BELOW SCA LEVELS. SCA SOUTHERLY SWELLS SHOULD CONTINUE THROUGH.
HAVE CONTINUED TO UNDERCUT WNA GUIDANCE BY 1-2 FT BASED ON GUIDANCE
TREND AND ITS PERFORMANCE THIS SUMMER.
POTENTIAL EXISTS FOR AN EXTENDED PERIOD OF HAZARDOUS OCEAN SEAS VIA
PERSISTENT LONG FETCH SOUTHERLY FLOW. WINDS ARE EXPECTED TO STAY
BELOW CRITERIA. UNDERCUT WAVEWATCH BY A ABOUT A FOOT ON THE OCEAN
WATERS FOR MUCH OF THE PERIOD.
&&
.HYDROLOGY...
PATTERN INTO TONIGHT CONTINUES TO LOOK CONDUCIVE TO BANDS OF HEAVY
RAIN SHOWERS AND THUNDERSTORMS TRAINING OVER THE SAME AREA...WHICH
WOULD CAUSE URBAN AND SMALL STREAM FLASH FLOODING.
ON AVERAGE 1/2 TO 1 1/2 INCHES OF RAINFALL EXPECTED ACROSS LI AND
CT...WITH 1 1/2 TO 2 1/2 INCHES OF RAINFALL ACROSS NE NJ AND THE
LOWER HUDSON VALLEY. THE HIGHER AMOUNTS IN BOTH AREAS WILL BE TO
THE N AND W.
LOCALLY HIGHER AMOUNTS ARE LIKELY IN THE PATH OF TRAINING ACTIVITY.
RAINFALL RATES OF 2 TO 3 INCHES PER HOUR HAVE BEEN OBSERVED WITH THE
STRONGER THUNDERSTORMS THIS AFTERNOON. NEEDLESS TO SAY IF THIS TYPE
OF ACTIVITY TRAINS OVER AN AREA FOR AN HOUR...URBAN AND SMALL
STREAM FLASH FLOODING WILL OCCUR.
THE MAIN THREAT FOR URBAN FLASH FLOODING LOOKS TO BE THROUGH 06Z
ACROSS THE WESTERN 1/2 OF THE CWA...AND THROUGH AROUND DAYBREAK
ACROSS LI/CT. SMALL STREAMS COULD CONTINUE RISING INTO FRIDAY
MORNING. MEANWHILE...MAIN STEM RIVERS WILL SEE RISES...BUT THEY
ARE EXPECTED TO REMAIN WELL WITHIN THEIR BANKS. WITH SOME
UNCERTAINTY ON THE EVOLUTION OF CONVECTION ON FRIDAY...WILL
CONTINUE FLASH FLOOD WATCH UNTIL 6 PM FRIDAY AND LET SUBSEQUENT
SHIFTS TAKE DOWN IF NEEDED.
ADDITIONAL BOUTS OF HEAVY SHOWERS AND THUNDERSTORMS ARE POSSIBLE
THIS WEEKEND INTO EARLY NEXT WEEK...POSING ADDITIONAL THREATS FOR
FLOODING.
FOR DETAILS ON SPECIFIC AREA RIVERS AND STREAMS...INCLUDING
OBSERVED AND FORECAST RIVER STAGES...PLEASE VISIT THE ADVANCED
HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...FLASH FLOOD WATCH THROUGH FRIDAY AFTERNOON FOR CTZ005>012.
NY...FLASH FLOOD WATCH THROUGH FRIDAY AFTERNOON FOR NYZ067>075-
078>081-176>179.
NJ...FLASH FLOOD WATCH THROUGH FRIDAY AFTERNOON FOR NJZ002-004-006-
103>108.
MARINE...DENSE FOG ADVISORY UNTIL 8 AM EDT FRIDAY FOR ANZ330-340-345-
350.
SMALL CRAFT ADVISORY UNTIL 6 AM EDT SATURDAY FOR ANZ350-353-
355.
&&
$$
AVIATION...JC
AREA FORECAST DISCUSSION
NWS NEW YORK NY
959 PM EDT THU JUN 27 2013
.SYNOPSIS...
SURFACE LOW PRESSURE ACROSS EASTERN PENNSYLVANIA WILL MOVE SLOWLY
NORTH THROUGH EASTERN NEW YORK TONIGHT INTO FRIDAY. A SERIES OF
LOW PRESSURE SYSTEMS WILL THEN IMPACT THE REGION THROUGH THE
WEEKEND AND INTO EARLY NEXT WEEK. BERMUDA HIGH PRESSURE
STRENGTHENS AND BUILDS BACK TOWARD THE EASTERN SEABOARD BY THE
MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
TSTMS HAVE MADE IT INTO THE CITY WITH HVY RAINS SPREADING UP THE
HUDSON VALLEY. ARC OF DEVELOPING CONVECTION TRACKING NEWD ACROSS
LI AND WILL SOON BE INTO CT. THIS IS A WARM FRONT JUST OFF THE SFC
AS EVIDENCED BY VEERING WINDS AT KDIX VIA THE VWP AS THE BAND
PASSED THRU AROUND 00Z.
WARM FRONT AT THE SFC PASSED THRU KBLM AFT 1Z.
00Z KOKX SOUNDING CAME IN WITH A PW OF 1.73 INCHES. THIS WAS A
TENTH BLW THE 12Z SOUNDING...BUT STILL INDICATIVE OF AN AIRMASS
CAPABLE OF TORRENTIAL DOWNPOURS. THE FFA REMAINS IN EFFECT.
HIGHEST FLOOD THREAT BASED ON THE RR QUAD OF THE H2 JET STILL
LOOKS TO FAVOR THE WRN HALF OF THE CWA.
SLY FLOW IN THE WARM SECTOR BEHIND THE FRONT COULD PRODUCE
ADDITIONAL LLVL SHEAR AS THE FLOW INTERACTS WITH LAND. THIS SHOULD
RESULT IN ISOLD SVR THREAT THRU THE NGT...ESPECIALLY THE S COASTS.
00Z HPC QPF WITH MANUAL ADJUSTMENTS UPWARD THRU 6Z USED IN THE
GRIDS.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
THE GREAT LAKES UPPER LOW CONTINUES TO DEEPEN INTO THE NORTHEAST
DURING THIS TIME PERIOD.
DRYING CONDITIONS ARE LIKELY FRIDAY MORNING ACROSS WESTERN SECTIONS
IN THE WAKE OF THE SHORTWAVE...WITH PARTIAL CLEARING. FAR EASTERN
SECTIONS WILL LIKELY SEE MORE IN THE WAY OF CLOUD COVER...AS THEY
WILL BE ON THE FRINGE OF THE TROPICAL CONVEYOR BELT.
TIMING OF SHORTWAVES AROUND THE UPPER LOW WILL DETERMINE EXACT
TIMING OF ADDITIONAL SHRA/TSRA ACTIVITY FRI AFT/FRI NIGHT...BUT
HIGHEST PROBABILITY WILL LIKELY BE ACROSS INTERIOR FRI AFT/EVE WITH
DIURNAL HEATING.
FLASH FLOOD THREAT APPEARS TO BE LOWER ON FRIDAY AS PWATS DROP TO
1.25 TO 1.5 INCHES IN THE WAKE OF THE SHORTWAVE. MARGINAL
INSTABILITY AND SHEAR ALSO INDICATE THAT STRONG TO SEVERE STORMS
WOULD BE ISOLATED...BUT THIS WILL ULTIMATELY BE DETERMINED BY
STRENGTH OF THE NEXT SHORTWAVE AND AMOUNT OF HEATING.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
UNSETTLED...MUGGY AND WARM CONDITIONS WILL BE THE RULE FOR MUCH OF
THE PERIOD AS AN UPPER TROF OVER THE NE AND OH VALLEY STATES THIS
WEEKEND CLOSES OFF AND RETROGRADES TOWARD THE MID SECTION OF THE
COUNTRY BY THE MIDDLE OF NEXT WEEK. THE AIRMASS WILL BECOME LOADED
WITH MOISTURE AS A DEEP-LAYERED S/SW FLOW BECOMES ESTABLISHED
BETWEEN THE RIDGE OVER THE WESTERN ATLANTIC AND THE UPPER TROF. THE
BEST CHANCE FOR ORGANIZED HEAVY RAINFALL WILL BE ON SUNDAY AS LOW
PRESSURE OVER THE TN AND OH VALLEYS LIFTS NORTH...SENDING A
STATIONARY FRONT JUST SOUTH AND EAST OF THE AREA NORTHWARD AS A WARM
FRONT. PW VALUES WILL BE AROUND 2 INCHES. THIS LOOKS TO BE A MAINLY
HEAVY RAINFALL EVENT AS WIND SHEAR IS MARGINAL AND THE AIRMASS IS
WARM ALOFT. SCT STRONG AND/OR SEVERE CONVECTION IS A POSSIBILITY SAT
AFT/EVE...PRIMARILY NORTH AND WEST OF NYC...WHERE DEEP-LAYERED SHEAR
WILL EXIST WITH THE RRQ OF THE UPPER JET LIFTING ACROSS THE HUDSON
VALLEY. A LIMITING FACTOR ON SAT WILL BE A BRIEF DRYING OUT OF THE
AIRMASS.
EARLY NEXT WEEK...WITH THE FRONTAL BOUNDARY NORTH OF THE REGION AND
THE AREA IN WARM SECTOR...CONVECTION LOOKS TO BE MAINLY DIURNAL IN
NATURE. MON MAY STILL REMAIN WET AS MODEL SOLUTIONS DIVERGE WITH
THE LOCATION OF THE BOUNDARY. THE 12Z ECMWF IS ACTUALLY WETTER ON
MON THAN SUN...A COMPLETE OPPOSITE OF THE GFS...BUT THIS IS DUE TO A
SLOWER TIMING OF THE FRONTAL WAVE.
KEEP IN MIND AN AIRMASS THIS MOIST AND UNSTABLE WILL TRIGGER
ISOLATED TO SCT CONVECTION ALMOST ANYTIME AND IT WILL NOT TAKE MUCH
FOR SOME ORGANIZATION OF CLUSTERS TO FORM POCKETS OF HEAVY RAINFALL.
THIS IS ESPECIALLY THE CASE SUN INTO MON.
AS FOR TEMPS...LOOKING AT BOTH HIGHS AND LOWS RUNNING A FEW DEGREES
ABOVE NORMAL. SHOULD THE AMOUNT OF CLOUD COVER FROM CONVECTION BE
LESS...DAYTIME HIGHS COULD BE SEVERAL DEGREES WARMER THAN CURRENTLY
FORECAST. GENERALLY LOOKING FOR HIGHS 80 TO 85...AND LOWS IN THE
UPPER 60S TO LOWER 70S.
&&
.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
LOW PRESSURE PASSES TO THE WEST TONIGHT AS IT DRIFTS NORTH. AN
ASSOCIATED FRONTAL BOUNDARY STALLS OVER THE AREA ON FRIDAY.
BAND OF SHOWERS WITH EMBEDDED TSTMS EXPECTED TO SHIFT IN FROM THE
SOUTH AND ENTER THE CITY AREA TERMINALS 01-03Z. COVERAGE OF
EMBEDDED TSTMS EXPECTED TO DIMINISH AS IT ENTERS A MORE STABLE
AIRMASS IN PLACE...SO TEMPO TSTMS IN TAFS.
VFR TO MVFR BEFORE MIDNIGHT...THEN MVFR TO IFR THEREAFTER. SHRA
STILL POSSIBLE AFTER MIDNIGHT.
SE WINDS 10-15KT THIS EVENING BCMG S-SW OVERNIGHT.
FOR FRIDAY...SCT SHRA AND TSTMS. BETTER OVERALL CHANCES IN THE AFTN.
VFR AND SW GUSTS AROUND 20 KT DEVELOPING BY AROUND NOON.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KEWR FCSTER COMMENTS: A GUST TO 35-40 KT POSSIBLE IN/NEAR TSTM THIS
EVENING. MVFR CIGS POSSIBLE BEFORE MIDNIGHT.
KJFK FCSTER COMMENTS: A GUST TO 35-40 KT POSSIBLE IN/NEAR TSTM THIS
EVENING. IFR CIGS POSSIBLE BEFORE MIDNIGHT.
KLGA FCSTER COMMENTS: A GUST TO 35-40 KT POSSIBLE IN/NEAR TSTM THIS
EVENING. MVFR CIGS POSSIBLE BEFORE MIDNIGHT.
KTEB FCSTER COMMENTS: A GUST TO 35-40 KT POSSIBLE IN/NEAR TSTM THIS
EVENING. MVFR CIGS POSSIBLE BEFORE MIDNIGHT.
KHPN FCSTER COMMENTS: A GUST TO 35-40 KT POSSIBLE IN/NEAR TSTM THIS
EVENING.
KISP FCSTER COMMENTS: CHC OF A TSTM AFTER MIDNIGHT.
.OUTLOOK FOR 00Z SAT THROUGH TUESDAY...
.FRI-TUE...SUB VFR POSSIBLE AT TIMES WITH PERIODS OF SHOWERS
AND TSTMS.
&&
.MARINE...
DENSE FOG ADVY ISSUEDC FOR THE ERN WATERS THRU TNGT.
OTHERWISE...SCA ON THE OCEAN WITH BUILDING SEAS THRU FRI.
S/SW FLOW CONTINUES THROUGH FRIDAY NIGHT...BUT WINDS ARE EXPECTED TO
BE BELOW SCA LEVELS. SCA SOUTHERLY SWELLS SHOULD CONTINUE THROUGH.
HAVE CONTINUED TO UNDERCUT WNA GUIDANCE BY 1-2 FT BASED ON GUIDANCE
TREND AND ITS PERFORMANCE THIS SUMMER.
POTENTIAL EXISTS FOR AN EXTENDED PERIOD OF HAZARDOUS OCEAN SEAS VIA
PERSISTENT LONG FETCH SOUTHERLY FLOW. WINDS ARE EXPECTED TO STAY
BELOW CRITERIA. UNDERCUT WAVEWATCH BY A ABOUT A FOOT ON THE OCEAN
WATERS FOR MUCH OF THE PERIOD.
&&
.HYDROLOGY...
PATTERN INTO TONIGHT CONTINUES TO LOOK CONDUCIVE TO BANDS OF HEAVY
RAIN SHOWERS AND THUNDERSTORMS TRAINING OVER THE SAME AREA...WHICH
WOULD CAUSE URBAN AND SMALL STREAM FLASH FLOODING.
ON AVERAGE 1/2 TO 1 1/2 INCHES OF RAINFALL EXPECTED ACROSS LI AND
CT...WITH 1 1/2 TO 2 1/2 INCHES OF RAINFALL ACROSS NE NJ AND THE
LOWER HUDSON VALLEY. THE HIGHER AMOUNTS IN BOTH AREAS WILL BE TO
THE N AND W.
LOCALLY HIGHER AMOUNTS ARE LIKELY IN THE PATH OF TRAINING ACTIVITY.
RAINFALL RATES OF 2 TO 3 INCHES PER HOUR HAVE BEEN OBSERVED WITH THE
STRONGER THUNDERSTORMS THIS AFTERNOON. NEEDLESS TO SAY IF THIS TYPE
OF ACTIVITY TRAINS OVER AN AREA FOR AN HOUR...URBAN AND SMALL
STREAM FLASH FLOODING WILL OCCUR.
THE MAIN THREAT FOR URBAN FLASH FLOODING LOOKS TO BE THROUGH 06Z
ACROSS THE WESTERN 1/2 OF THE CWA...AND THROUGH AROUND DAYBREAK
ACROSS LI/CT. SMALL STREAMS COULD CONTINUE RISING INTO FRIDAY
MORNING. MEANWHILE...MAIN STEM RIVERS WILL SEE RISES...BUT THEY
ARE EXPECTED TO REMAIN WELL WITHIN THEIR BANKS. WITH SOME
UNCERTAINTY ON THE EVOLUTION OF CONVECTION ON FRIDAY...WILL
CONTINUE FLASH FLOOD WATCH UNTIL 6 PM FRIDAY AND LET SUBSEQUENT
SHIFTS TAKE DOWN IF NEEDED.
ADDITIONAL BOUTS OF HEAVY SHOWERS AND THUNDERSTORMS ARE POSSIBLE
THIS WEEKEND INTO EARLY NEXT WEEK...POSING ADDITIONAL THREATS FOR
FLOODING.
FOR DETAILS ON SPECIFIC AREA RIVERS AND STREAMS...INCLUDING
OBSERVED AND FORECAST RIVER STAGES...PLEASE VISIT THE ADVANCED
HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...FLASH FLOOD WATCH THROUGH FRIDAY AFTERNOON FOR CTZ005>012.
NY...FLASH FLOOD WATCH THROUGH FRIDAY AFTERNOON FOR NYZ067>075-
078>081-176>179.
NJ...FLASH FLOOD WATCH THROUGH FRIDAY AFTERNOON FOR NJZ002-004-006-
103>108.
MARINE...DENSE FOG ADVISORY UNTIL 8 AM EDT FRIDAY FOR ANZ330-340-345-
350.
SMALL CRAFT ADVISORY UNTIL 6 AM EDT SATURDAY FOR ANZ350-353-
355.
&&
$$
SYNOPSIS...NV
NEAR TERM...JMC
SHORT TERM...NV
LONG TERM...DW
AVIATION...JC
MARINE...JMC/NV/DW
HYDROLOGY...NV/DW
AREA FORECAST DISCUSSION
NWS NEW YORK NY
811 PM EDT THU JUN 27 2013
.SYNOPSIS...
SURFACE LOW PRESSURE ACROSS SOUTHEASTERN PENNSYLVANIA WILL MOVE
SLOWLY NORTH THROUGH EASTERN NEW YORK TONIGHT INTO FRIDAY. A SERIES
OF LOW PRESSURE SYSTEMS WILL THEN IMPACT THE REGION THROUGH THE
WEEKEND AND INTO EARLY NEXT WEEK. BERMUDA HIGH PRESSURE STRENGTHENS
AND BUILDS BACK TOWARD THE EASTERN SEABOARD BY THE MIDDLE OF NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
SLOWED POPS BASED ON RADAR AND STLT WITH THE 730 UPDATE. INCLUDED
FOG IN THE FCST WITH DENSE FOG REPORTED IN NANTUCKET AND 69/69 AT
BUOY 44017. WESTHAMPTON AND GROTON ALREADY REPORTING BR. BEST
FLOODING CHC APPEARS TO BE ACROSS WRN ZONES WITH RR QUAD OF H2
JET. POPULATED QPF WITH 00Z HPC NUMBERS...BUT BUMPED THEM UP
SIGNIFICANTLY THRU 6Z TO REFLECT THE HIGH MOISTURE CONTENT
CONVECTIVE ENVIRONMENT. OTHERWISE...
SHORTWAVE TROUGH OVER CENTRAL PA WILL CONTINUE TO PIVOT NE THROUGH
THIS EVENING. MODELS ARE INDICATING THAT THIS SHORTWAVE MAY BE
SHEARING A BIT AS IT PIVOTS THROUGH AND GETS ABSORBED INTO AN UPPER
LOW DIGGING INTO THE GREAT LAKES.
AT THE SURFACE...LOW PRESSURE OVER SERN PA WILL SLIDE NE THROUGH
EASTERN NY TONIGHT.
APPROACHING UPPER LEVEL SUPPORT AND LLJ ENERGY SHOULD ALLOW FOR
INCREASING SHOWER AND THUNDERSTORM DEVELOPMENT ALONG THE SEABREEZE
BOUNDARY AND HIGHER ELEVATIONS OF NE NJ AND THE LOWER HUDSON
VALLEY THROUGH LATE THIS AFTERNOON. THEN AS THE SHORTWAVE
AXIS/SURFACE LOW APPROACH...WOULD EXPECT INCREASING TSTM ACTIVITY
ACROSS SE PA/DE/S NY TO LIFT INTO THE LOWER HUDSON VALLEY...NE
NJ...NYC METRO AND SW CT THIS EVENING.
WITH MARGINAL TO MODERATE INSTABILITY ACROSS OUR FAR WESTERN AREAS
AREA...MODEST SHEAR...AND INCREASING HELICITY A FEW STRONG TO SEVERE
STORMS ARE POSSIBLE THROUGH THIS EVENING...MAINLY WEST OF THE HUDSON
RIVER. THE LIMITING FACTOR WILL BE WANING INSTABILITY...BUT COULD BE
OVERCOME BY INCREASING SYNOPTIC SUPPORT. STRONG WINDS WOULD BE THE
MAIN SEVERE THREAT...BUT CAN NOT RULE OUT AN ISOLATED WEAK TORNADO
WITH ANY ROTATING STORMS. BASED ON PWATS AROUND 2 INCHES...GOOD
SYNOPTIC SUPPORT...AND WIND FIELDS INDICATIVE OF TRAINING
CELLS...MAIN OVERALL THREAT CONTINUES TO BE FLASH
FLOODING...WHICH SHOULD PEAK THIS EVENING ACROSS THE WESTERN 1/2 OF
THE CWA.
THEN AS THE SYNOPTIC FORCING CONTINUES TO PUSH EAST LATE THIS EVENING
INTO THE OVERNIGHT...THE THREAT FOR HEAVY SHOWERS AND TSTMS WILL
LIKELY SHIFT EAST ACROSS LI AND CT...WITH THE THREAT FOR URBAN FLASH
FLOODING DIMINISHING TO THE WEST.
THERE IS SOME UNCERTAINTY IN HOW WIDESPREAD HEAVY SHOWER/TSRA
ACTIVITY WILL BE ACROSS LI AND CT OVERNIGHT. DUE TO THE WEAKENING OF
THE SURFACE TROUGH AS THE SHORTWAVE SHEARS NW...THERE WILL BE NO
CLEAR CUT CONVERGENCE BOUNDARY TO FOCUS CONVECTION. WITH THIS
SAID THE SHRA/TSTM ACTIVITY COULD BE MORE STREAKY IN NATURE ACROSS
LI/CT TONIGHT...WITH FRICTIONAL CONVERGENCE LOCALLY ENHANCING
ACTIVITY. THIS IS SUPPORTED BY SOME OF THE HIGH RES MODEL OUTPUT.
WITH DEEP MOISTURE AXIS ADVECTING OVER THE REGION...MARGINAL
INSTABILITY...AND STRONG LLJ SUPPORT...THE FLASH FLOODING THREAT
WILL EXIST WHERE THESE RAIN BANDS DEVELOP...BUT COVERAGE MAY NOT
BE AS WIDESPREAD AS ACROSS WESTERN PORTIONS OF THE AREA.
HEAVIEST RAIN SHOWER/TSRA ACTIVITY LIKELY PUSHES EAST OF THE REGION
BY DAYBREAK AS SHORTWAVE AND LLJ PIVOT N AND E.
SEE HYDROLOGY SECTION FOR MORE ON FLOODING THREAT.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
THE GREAT LAKES UPPER LOW CONTINUES TO DEEPEN INTO THE NORTHEAST
DURING THIS TIME PERIOD.
DRYING CONDITIONS ARE LIKELY FRIDAY MORNING ACROSS WESTERN SECTIONS
IN THE WAKE OF THE SHORTWAVE...WITH PARTIAL CLEARING. FAR EASTERN
SECTIONS WILL LIKELY SEE MORE IN THE WAY OF CLOUD COVER...AS THEY
WILL BE ON THE FRINGE OF THE TROPICAL CONVEYOR BELT.
TIMING OF SHORTWAVES AROUND THE UPPER LOW WILL DETERMINE EXACT
TIMING OF ADDITIONAL SHRA/TSRA ACTIVITY FRI AFT/FRI NIGHT...BUT
HIGHEST PROBABILITY WILL LIKELY BE ACROSS INTERIOR FRI AFT/EVE WITH
DIURNAL HEATING.
FLASH FLOOD THREAT APPEARS TO BE LOWER ON FRIDAY AS PWATS DROP TO
1.25 TO 1.5 INCHES IN THE WAKE OF THE SHORTWAVE. MARGINAL
INSTABILITY AND SHEAR ALSO INDICATE THAT STRONG TO SEVERE STORMS
WOULD BE ISOLATED...BUT THIS WILL ULTIMATELY BE DETERMINED BY
STRENGTH OF THE NEXT SHORTWAVE AND AMOUNT OF HEATING.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
UNSETTLED...MUGGY AND WARM CONDITIONS WILL BE THE RULE FOR MUCH OF
THE PERIOD AS AN UPPER TROF OVER THE NE AND OH VALLEY STATES THIS
WEEKEND CLOSES OFF AND RETROGRADES TOWARD THE MID SECTION OF THE
COUNTRY BY THE MIDDLE OF NEXT WEEK. THE AIRMASS WILL BECOME LOADED
WITH MOISTURE AS A DEEP-LAYERED S/SW FLOW BECOMES ESTABLISHED
BETWEEN THE RIDGE OVER THE WESTERN ATLANTIC AND THE UPPER TROF. THE
BEST CHANCE FOR ORGANIZED HEAVY RAINFALL WILL BE ON SUNDAY AS LOW
PRESSURE OVER THE TN AND OH VALLEYS LIFTS NORTH...SENDING A
STATIONARY FRONT JUST SOUTH AND EAST OF THE AREA NORTHWARD AS A WARM
FRONT. PW VALUES WILL BE AROUND 2 INCHES. THIS LOOKS TO BE A MAINLY
HEAVY RAINFALL EVENT AS WIND SHEAR IS MARGINAL AND THE AIRMASS IS
WARM ALOFT. SCT STRONG AND/OR SEVERE CONVECTION IS A POSSIBILITY SAT
AFT/EVE...PRIMARILY NORTH AND WEST OF NYC...WHERE DEEP-LAYERED SHEAR
WILL EXIST WITH THE RRQ OF THE UPPER JET LIFTING ACROSS THE HUDSON
VALLEY. A LIMITING FACTOR ON SAT WILL BE A BRIEF DRYING OUT OF THE
AIRMASS.
EARLY NEXT WEEK...WITH THE FRONTAL BOUNDARY NORTH OF THE REGION AND
THE AREA IN WARM SECTOR...CONVECTION LOOKS TO BE MAINLY DIURNAL IN
NATURE. MON MAY STILL REMAIN WET AS MODEL SOLUTIONS DIVERGE WITH
THE LOCATION OF THE BOUNDARY. THE 12Z ECMWF IS ACTUALLY WETTER ON
MON THAN SUN...A COMPLETE OPPOSITE OF THE GFS...BUT THIS IS DUE TO A
SLOWER TIMING OF THE FRONTAL WAVE.
KEEP IN MIND AN AIRMASS THIS MOIST AND UNSTABLE WILL TRIGGER
ISOLATED TO SCT CONVECTION ALMOST ANYTIME AND IT WILL NOT TAKE MUCH
FOR SOME ORGANIZATION OF CLUSTERS TO FORM POCKETS OF HEAVY RAINFALL.
THIS IS ESPECIALLY THE CASE SUN INTO MON.
AS FOR TEMPS...LOOKING AT BOTH HIGHS AND LOWS RUNNING A FEW DEGREES
ABOVE NORMAL. SHOULD THE AMOUNT OF CLOUD COVER FROM CONVECTION BE
LESS...DAYTIME HIGHS COULD BE SEVERAL DEGREES WARMER THAN CURRENTLY
FORECAST. GENERALLY LOOKING FOR HIGHS 80 TO 85...AND LOWS IN THE
UPPER 60S TO LOWER 70S.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
LOW PRESSURE PASSES TO THE WEST TONIGHT AS IT DRIFTS NORTH. AN
ASSOCIATED FRONTAL BOUNDARY STALLS OVER THE AREA ON FRIDAY.
BAND OF SHOWERS WITH EMBEDDED TSTMS EXPECTED TO SHIFT IN FROM THE
SOUTH AND ENTER THE CITY AREA TERMINALS 01-03Z. COVERAGE OF
EMBEDDED TSTMS EXPECTED TO DIMINISH AS IT ENTERS A MORE STABLE
AIRMASS IN PLACE...SO TEMPO TSTMS IN TAFS.
VFR TO MVFR BEFORE MIDNIGHT...THEN MVFR TO IFR THEREAFTER. SHRA
STILL POSSIBLE AFTER MIDNIGHT.
SE WINDS 10-15KT THIS EVENING BCMG S-SW OVERNIGHT.
FOR FRIDAY...SCT SHRA AND TSTMS. BETTER OVERALL CHANCES IN THE AFTN.
VFR AND SW GUSTS AROUND 20 KT DEVELOPING BY AROUND NOON.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KEWR FCSTER COMMENTS: A GUST TO 35-40 KT POSSIBLE IN/NEAR TSTM THIS
EVENING. MVFR CIGS POSSIBLE BEFORE MIDNIGHT.
KJFK FCSTER COMMENTS: A GUST TO 35-40 KT POSSIBLE IN/NEAR TSTM THIS
EVENING. IFR CIGS POSSIBLE BEFORE MIDNIGHT.
KLGA FCSTER COMMENTS: A GUST TO 35-40 KT POSSIBLE IN/NEAR TSTM THIS
EVENING. MVFR CIGS POSSIBLE BEFORE MIDNIGHT.
KTEB FCSTER COMMENTS: A GUST TO 35-40 KT POSSIBLE IN/NEAR TSTM THIS
EVENING. MVFR CIGS POSSIBLE BEFORE MIDNIGHT.
KHPN FCSTER COMMENTS: A GUST TO 35-40 KT POSSIBLE IN/NEAR TSTM THIS
EVENING.
KISP FCSTER COMMENTS: CHC OF A TSTM AFTER MIDNIGHT.
.OUTLOOK FOR 00Z SAT THROUGH TUESDAY...
.FRI-TUE...SUB VFR POSSIBLE AT TIMES WITH PERIODS OF SHOWERS
AND TSTMS.
&&
.MARINE...
A STRENGTHENING SOUTHERLY FLOW IS EXPECTED TO DEVELOP MARGINAL SCA
SEAS OVER THE OCEAN WATERS TONIGHT. MARGINAL SCA GUSTS ARE POSSIBLE
AS A LOW LEVEL JET MOVES OVER THE AREA TONIGHT...AND PASSES EAST
FRIDAY MORNING.
S/SW FLOW CONTINUES THROUGH FRIDAY NIGHT...BUT WINDS ARE EXPECTED TO
BE BELOW SCA LEVELS. SCA SOUTHERLY SWELLS SHOULD CONTINUE THROUGH.
HAVE CONTINUED TO UNDERCUT WNA GUIDANCE BY 1-2 FT BASED ON GUIDANCE
TREND AND ITS PERFORMANCE THIS SUMMER.
POTENTIAL EXISTS FOR AN EXTENDED PERIOD OF HAZARDOUS OCEAN SEAS VIA
PERSISTENT LONG FETCH SOUTHERLY FLOW. WINDS ARE EXPECTED TO STAY
BELOW CRITERIA. UNDERCUT WAVEWATCH BY A ABOUT A FOOT ON THE OCEAN
WATERS FOR MUCH OF THE PERIOD.
&&
.HYDROLOGY...
PATTERN INTO TONIGHT CONTINUES TO LOOK CONDUCIVE TO BANDS OF HEAVY
RAIN SHOWERS AND THUNDERSTORMS TRAINING OVER THE SAME AREA...WHICH
WOULD CAUSE URBAN AND SMALL STREAM FLASH FLOODING.
ON AVERAGE 1/2 TO 1 1/2 INCHES OF RAINFALL EXPECTED ACROSS LI AND
CT...WITH 1 1/2 TO 2 1/2 INCHES OF RAINFALL ACROSS NE NJ AND THE
LOWER HUDSON VALLEY. THE HIGHER AMOUNTS IN BOTH AREAS WILL BE TO
THE N AND W.
LOCALLY HIGHER AMOUNTS ARE LIKELY IN THE PATH OF TRAINING ACTIVITY.
RAINFALL RATES OF 2 TO 3 INCHES PER HOUR HAVE BEEN OBSERVED WITH THE
STRONGER THUNDERSTORMS THIS AFTERNOON. NEEDLESS TO SAY IF THIS TYPE
OF ACTIVITY TRAINS OVER AN AREA FOR AN HOUR...URBAN AND SMALL
STREAM FLASH FLOODING WILL OCCUR.
THE MAIN THREAT FOR URBAN FLASH FLOODING LOOKS TO BE THROUGH 06Z
ACROSS THE WESTERN 1/2 OF THE CWA...AND THROUGH AROUND DAYBREAK
ACROSS LI/CT. SMALL STREAMS COULD CONTINUE RISING INTO FRIDAY
MORNING. MEANWHILE...MAIN STEM RIVERS WILL SEE RISES...BUT THEY
ARE EXPECTED TO REMAIN WELL WITHIN THEIR BANKS. WITH SOME
UNCERTAINTY ON THE EVOLUTION OF CONVECTION ON FRIDAY...WILL
CONTINUE FLASH FLOOD WATCH UNTIL 6 PM FRIDAY AND LET SUBSEQUENT
SHIFTS TAKE DOWN IF NEEDED.
ADDITIONAL BOUTS OF HEAVY SHOWERS AND THUNDERSTORMS ARE POSSIBLE
THIS WEEKEND INTO EARLY NEXT WEEK...POSING ADDITIONAL THREATS FOR
FLOODING.
FOR DETAILS ON SPECIFIC AREA RIVERS AND STREAMS...INCLUDING
OBSERVED AND FORECAST RIVER STAGES...PLEASE VISIT THE ADVANCED
HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...FLASH FLOOD WATCH THROUGH FRIDAY AFTERNOON FOR CTZ005>012.
NY...FLASH FLOOD WATCH THROUGH FRIDAY AFTERNOON FOR NYZ067>075-
078>081-176>179.
NJ...FLASH FLOOD WATCH THROUGH FRIDAY AFTERNOON FOR NJZ002-004-006-
103>108.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT SATURDAY FOR ANZ350-353-
355.
&&
$$
SYNOPSIS...NV
NEAR TERM...JMC/NV
SHORT TERM...NV
LONG TERM...DW
AVIATION...JC
MARINE...NV/DW
HYDROLOGY...NV/DW
AREA FORECAST DISCUSSION
NWS ALBANY NY
759 PM EDT THU JUN 27 2013
.SYNOPSIS...
AN AREA OF LOW PRESSURE WILL MOVE FROM PENNSYLVANIA
ACROSS UPSTATE NEW YORK TONIGHT...ALLOWING FOR PERIODS OF HEAVY RAIN
AND THUNDERSTORMS...WITH THE POTENTIAL FOR FLOODING. THE LOW
PRESSURE SYSTEM WILL MOVE SLOWLY NORTHEAST TOWARDS SOUTHERN QUEBEC
TOMORROW INTO SATURDAY WITH HUMID CONDITIONS...AND CONTINUED CHANCES
OF SHOWERS AND THUNDERSTORMS INTO NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
...FLOOD WATCH CONTINUES THROUGH FRIDAY AFTERNOON...
AS OF 750 PM EDT...STEADY RAINFALL STILL REMAINS JUST TO THE WEST
OF THE FORECAST AREA OVER CENTRAL NY...NE PA...AND NORTHERN NJ AT
THIS TIME...ALTHOUGH A FEW SHOWERS AND THUNDERSTORMS HAVE FLARED
UP FROM TIME TO TIME ACROSS VARIOUS PARTS OF THE AREA EARLY THIS
EVENING. INSTABILITY WILL START TO WANE AS CLOUDS HAVE INCREASED
AND DAYTIME HEATING IS LOST. STILL SBCAPE VALUES OF AROUND
500-1000 J/KG STILL EXIST AT THIS HOUR SO SOME CELLS WILL PRODUCE
LIGHTNING AND DOWNPOURS. THE STEADIER RAIN WITH EMBEDDED
CONVECTION SHOULD MOVE INTO THE AREA FROM SOUTHWEST TO NORTHEAST
LATER THIS EVENING AND INTO THE OVERNIGHT HOURS.
AT 500 HPA...A SHARP SHORTWAVE TROUGH IS LOCATED OVER CENTRAL PA
AND CONTINUES TO LIFT TOWARDS THE NORTHEAST. AT THE SURFACE...AN
UNUSUALLY STRONG LOW FOR MID JUNE /2 TO 4 STD BELOW NORMAL/ IS
LOCATED NEAR READING PA. STRONG SOUTHERLY FLOW AHEAD OF THIS
SYSTEM IS ADVECTING PLENTY OF MOISTURE INTO THE REGION. PWAT
VALUES ARE EXPECTED TO REACH CLOSE TO 2.00 INCHES...WHICH IS ABOUT
2-3 STD ABOVE NORMAL.
CLOUDS WILL CONTINUE TO THICKEN THROUGH THE EVENING EVENING AS
THE SYSTEM MOVES TOWARDS THE AREA. THE LOW PRESSURE WILL MOVE
FROM THE POCONOS AND CATSKILLS TOWARDS THE SARATOGA REGION BY
SUNRISE...BRINGING A STEADY SHIELD OF RAIN ACROSS OUR AREA
OVERNIGHT. OUR LOCAL HIRES WRF AND THE 3KM HRRR ALL SHOW THIS
FAIRLY CLEARLY. THIS SYSTEM HAS PRODUCED HEAVY RAIN UPSTREAM
ACROSS WESTERN/CENTRAL PA...AND ITS EXPECTED TO DO THE SAME
OVERNIGHT AS IT MOVES ACROSS OUR AREA. RAINFALL RATES OF ONE HALF
TO ONE INCH PER HOUR WILL BE POSSIBLE AT TIMES...WITH LOCALLY
HEAVY AMOUNTS BRIEFLY POSSIBLE AS WELL. THERE IS A POSSIBILITY OF
SOME FLASH FLOODING TONIGHT...AS WELL AS TYPICAL URBAN...SMALL
STREAM AND POOR DRAINAGE FLOODING. /SEE OUR HYDRO SECTION FOR MORE
DETAILS INCLUDING EXPECTED QPF VALUES/. THE BEST CHC OF SEEING
THUNDER WILL BE ON THE LEADING EDGE OF THIS STEADY RAIN AS
WELL...BASED ON UPSTREAM TRENDS CURRENTLY ONGOING ACROSS NORTHEAST
PA AND INTO NEW JERSEY.
STEADY RAIN WILL START TO TAPER OFF ACROSS SOUTHERN AREAS TOWARDS
DAYBREAK...BUT IT SHOULD STILL BE RAINING FAIRLY STEADILY FROM THE
CAPITAL REGION ON NORTH.
MIN TEMPS WILL REMAIN MILD AND MUGGY...WITH READING IN THE 60S TO
LOW 70S ACROSS THE ENTIRE AREA.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
STEADY RAIN WILL CONTINUE ACROSS NORTHERN AND EASTERN AREAS
DURING THE MORNING HOURS...BUT IT SHOULD START TO TAPER OFF BY
NOON. AT THIS POINT...THE CONCERN WILL BECOME FOR RIVER
FLOODING...AS ALL THE RUNOFF FROM THE OVERNIGHT RAIN REACHES THE
MAIN STEM RIVERS. MEANWHILE...SOME ADDITIONAL RAIN SHOWERS OR
THUNDERSTORMS WILL BE POSSIBLE IN THE AFTN AS THE WHOLE UPPER
TROUGH CLOSES OFF TO OUR WEST AND SLOWLY SPINS. SKIES WILL BE
FAIRLY CLOUDY FOR MUCH OF THE DAY...WITH MAX TEMPS COOLER THAN
RECENT DAYS /MAINLY IN THE 70S WITH SOME LOW 80S IN FAR SOUTHERN AREAS/.
IT WILL REMAIN WET AND UNSETTLED FOR FRI NIGHT THROUGH SAT NIGHT
AS THE CLOSED SLOW MOVING UPPER TROUGH REMAINS TO OUR WEST AND A
STRONG JET REMAINS OVERHEAD. THERE WILL BE A CONTINUED THREAT FOR
SHOWERS AND THUNDERSTORMS...WITH THE BEST CHC OF THUNDER DURING
THE AFTN AND EVENING HOURS. IT LOOKS FAIRLY CLOUDY...ALTHOUGH SOME
BREAKS OF SUN ARE POSSIBLE ON SAT AFTN FOR EASTERN/SOUTHERN AREAS. MIN
TEMPS WILL CONTINUE TO BE MILD WITH MAINLY 60S. DAYTIME HIGHS ON
SAT WILL RANGE FROM THE MID 70S TO MID 80S...WITH THE WARMEST
TEMPS IN THOSE AREAS THAT GET SOME BREAKS OF SUN BETWEEN SHOWERS
AND STORMS.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
A RATHER REPETITIVE FORECAST IS SHAPING UP FOR THE DURATION OF THE
LONG TERM PERIOD. MODEL GUIDANCE IN RELATIVELY GOOD AGREEMENT DURING
THIS TIME WITH REGARDS TO THE LARGE SCALE FEATURES.
LATEST 12Z MODELS STILL SHOWS A BLOCKING PATTERN WILL BE IN PLACE
ACROSS MUCH OF NORTH AMERICA...WITH A PERSISTENT BERMUDA HIGH OVER
THE WESTERN ATLANTIC AND A TROUGH OVER THE GREAT LAKES AND MIDWEST
WITH A STRONG RIDGE OVER THE WESTERN CONUS. THIS SYNOPTIC SET UP
WILL PUT THE NORTHEASTERN STATES IN A GOOD POSITION OF POSITIVE
850-700 HPA SOUTH AND SOUTHWEST WIND FLOW ANOMALIES OF AROUND 2 TO 3
S.D. FLOWING RIGHT OVER THE REGION BRINGING GULF OF MEXICO AND
SOUTHERN ATLANTIC MOISTURE INTO THE REGION. THIS IN RETURN WILL
ALLOW WEAK DISTURBANCES TO RIDE ALONG THE UPPER LEVEL WIND FLOW
BETWEEN THE TWO LARGE SYNOPTIC FEATURES AND CAUSE PERSISTENT CHANCES
OF SHOWERS AND EVEN A FEW ISOLATED THUNDERSTORMS WITH THIS
PERTURBATION PATTERN THROUGHOUT THE LONG TERM PERIOD. ALONG WITH
WIND ANOMALIES...HEIGHT ANOMALIES OF -1 TO -2 S.D. ASSOCIATED WITH
THE DIGGING TROUGH TO THE WEST OF THE REGION AND HEIGHT ANOMALIES
WITH THE HIGH PRESSURE IN THE ATLANTIC OF 1.5 TO 2 S.D. ACCORDING TO
THE LATEST MODELS ALONG WITH WEAK WINDS ALOFT...THIS PATTERN WILL
ALMOST BE STATIONARY THROUGH THE EXTENDED PERIOD
THIS PATTERN WILL CONTINUE TO RESULT MOSTLY CLOUDY SKIES WITH HUMID
CONDITIONS. HIGHS SUNDAY THROUGH THURSDAY WILL GENERALLY BE IN THE
MID 70S TO MID 80S WITH LOW TEMPERATURES RANGING FROM THE LOW 60S TO
UPPER 60S THROUGHOUT THIS PERIOD.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
CONDITIONS WILL DETERIORATE LATER THIS EVENING INTO THE OVERNIGHT
HOURS...AS AN ANOMALOUSLY STRONG LOW PRESSURE SYSTEM MOVES INTO THE
AREA FROM PA. THIS WILL SPREAD A SHIELD OF STEADY RAINFALL WITH
EMBEDDED CONVECTIVE ELEMENTS OF HEAVIER RAIN. THE STEADIER RAIN
SHOULD MOVE IN ACROSS THE TERMINALS BETWEEN 02Z-03Z.
UNTIL THEN...WATCHING A SMALL CLUSTER OF THUNDERSTORMS WITH
DOWNPOURS THAT HAVE DEVELOPED SOUTH OF KALB AND ARE APPROACHING
THE TERMINAL. IT APPEARS AS THOUGH THE STRONGEST PART OF THE
STORM WILL PASS BY TO THE WEST OF THE AIRPORT...BUT A FEW MODERATE
BURSTS OF RAIN AND SOME THUNDER ARE STILL POSSIBLE. SO WILL
MENTION A TEMPO FOR THUNDER AND MVFR CONDITIONS THERE.
OTHERWISE...CONDITIONS WILL DETERIORATE FROM VFR TO MVFR LATER
THIS EVENING...WITH PERIODS OF IFR DEVELOPING WITHIN ANY HEAVIER
RAINFALL. WILL MENTION TEMPO GROUPS BETWEEN EITHER 03Z-06Z FOR
OCCASIONAL IFR FOR KPOU/KALB...AND 04Z-06Z FOR KPSF/KGFL.
CONDITIONS ARE EXPECTED TO VARY BETWEEN IFR/MVFR FOR THE REST OF
THE OVERNIGHT HOURS AS RAINFALL CONTINUES. THE RAIN WILL TAPER OFF
TO SHOWERS BY 12Z...WITH CONDITIONS SLOWLY IMPROVING TO MVFR THEN
POSSIBLY VFR IF ENOUGH DRYING OCCURS BY 16Z-18Z FRIDAY.
WINDS WILL BE GENERALLY EAST-NORTHEAST AROUND 3 TO 6 KT TONIGHT...
BECOMING SOUTHERLY FRIDAY AROUND 5 TO 10 KT.
OUTLOOK...
FRI NIGHT-TUE...VFR/MVFR. CHC SHRA/TSRA. POSSIBLE LATE NIGHT AND
OR EARLY MORNING FOG/LOW STRATUS WITH IFR.
&&
.FIRE WEATHER...
NO FIRE WEATHER ISSUES AT THIS TIME DUE TO PERSISTENT WET
CONDITIONS. HEAVY RAIN WILL BE POSSIBLE TONIGHT INTO TOMORROW
MORNING...WITH ADDITIONAL SHOWERS POSSIBLE THROUGH MUCH OF NEXT
WEEK. RH VALUES WILL REMAIN RATHER HIGH RIGHT THROUGH THE WEEKEND.
&&
.HYDROLOGY...
A FLOOD WATCH REMAINS IN EFFECT THROUGH FRIDAY AFTERNOON. THERE
WILL BE A THREAT FOR BOTH FLASH FLOODING AND MAIN STEM RIVER
FLOODING OVER THE NEXT SEVERAL DAYS.
A STRONG LOW PRESSURE SYSTEM WILL MOVE ACROSS THE AREA TONIGHT INTO
THE DAY ON FRIDAY. WITH PWATS VALUES EXPECTED TO EXCEED 2 STD
ABOVE NORMAL...AND SURFACE DEWPOINTS IN THE 60S TO NEAR 70...HEAVY
RAINFALL IS LIKELY. A RAIN SHIELD ASSOCIATED WITH THIS STORM WILL
MOVE ACROSS THE AREA FROM SOUTH TO NORTH BEGINNING THIS EVENING.
EMBEDDED CONVECTIVE ELEMENTS WILL ALLOW FOR LOCALLY HEAVY
RAINFALL WITHIN A STRATIFORM RAIN SHIELD. INITIALLY...THERE WILL
BE A CONCERN FOR LOCALIZED FLASH FLOODING DUE TO THE EMBEDDED
CONVECTION. THIS WILL EVENTUALLY TRANSITION TO FLOODING FOR THE
MAIN STEMS RIVERS FRIDAY MORNING INTO THE AFTERNOON.
BASIN AVERAGE RAINFALL IS FORECASTED FROM 1.5 TO 3 INCHES...ALTHOUGH
HIGHER TERRAIN AREAS OF THE CATSKILLS AND ADIRONDACKS COULD SEE IN
EXCESS OF 3 INCHES. ISOLATED POINT RAINFALL TOTALS OF UP TO 5
INCHES CANNOT BE RULED OUT ACROSS THE HIGHEST TERRAIN OF THE EASTERN
CATSKILLS AND THE ERN DACKS.
THE AREA MOST SUSCEPTIBLE TO MAIN STEM RIVER FLOODING WILL LIKELY BE
THE MOHAWK RIVER BASIN BASED ON THE LATEST NERFC HYDROGRAPHS. THIS
AREA HAS SEEN A LOT OF RAIN LATELY...AND SOILS ARE RATHER SATURATED.
THE NERFC HAS ALREADY FORECASTED SEVERAL POINTS TO RISE ABOVE
FLOOD STAGE DURING THE DAY FRIDAY...MAINLY ACROSS THE NORTHERN
HALF OF THE HSA. HOWEVER...THE CATSKILL BASINS WILL NEED TO BE
MONITORED CLOSELY AS WELL.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH THROUGH FRIDAY AFTERNOON FOR CTZ001-013.
NY...FLOOD WATCH THROUGH FRIDAY AFTERNOON FOR NYZ032-033-038>043-
047>054-058>061-063>066-082>084.
MA...FLOOD WATCH THROUGH FRIDAY AFTERNOON FOR MAZ001-025.
VT...FLOOD WATCH THROUGH FRIDAY AFTERNOON FOR VTZ013>015.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS/JPV
SHORT TERM...FRUGIS
LONG TERM...LFM
AVIATION...JPV
FIRE WEATHER...FRUGIS
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS NEW YORK NY
741 PM EDT THU JUN 27 2013
.SYNOPSIS...
SURFACE LOW PRESSURE ACROSS SOUTHEASTERN PENNSYLVANIA WILL MOVE
SLOWLY NORTH THROUGH EASTERN NEW YORK TONIGHT INTO FRIDAY. A SERIES
OF LOW PRESSURE SYSTEMS WILL THEN IMPACT THE REGION THROUGH THE
WEEKEND AND INTO EARLY NEXT WEEK. BERMUDA HIGH PRESSURE STRENGTHENS
AND BUILDS BACK TOWARD THE EASTERN SEABOARD BY THE MIDDLE OF NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
SLOWED POPS BASED ON RADAR AND STLT WITH THE 730 UPDATE. INCLUDED
FOG IN THE FCST WITH DENSE FOG REPORTED IN NANTUCKET AND 69/69 AT
BUOY 44017. WESTHAMPTON AND GROTON ALREADY REPORTING BR. BEST
FLOODING CHC APPEARS TO BE ACROSS WRN ZONES WITH RR QUAD OF H2
JET. POPULATED QPF WITH 00Z HPC NUMBERS...BUT BUMPED THEM UP
SIGNIFICANTLY THRU 6Z TO REFLECT THE HIGH MOISTURE CONTENT
CONVECTIVE ENVIRONMENT. OTHERWISE...
SHORTWAVE TROUGH OVER CENTRAL PA WILL CONTINUE TO PIVOT NE THROUGH
THIS EVENING. MODELS ARE INDICATING THAT THIS SHORTWAVE MAY BE
SHEARING A BIT AS IT PIVOTS THROUGH AND GETS ABSORBED INTO AN UPPER
LOW DIGGING INTO THE GREAT LAKES.
AT THE SURFACE...LOW PRESSURE OVER SERN PA WILL SLIDE NE THROUGH
EASTERN NY TONIGHT.
APPROACHING UPPER LEVEL SUPPORT AND LLJ ENERGY SHOULD ALLOW FOR
INCREASING SHOWER AND THUNDERSTORM DEVELOPMENT ALONG THE SEABREEZE
BOUNDARY AND HIGHER ELEVATIONS OF NE NJ AND THE LOWER HUDSON
VALLEY THROUGH LATE THIS AFTERNOON. THEN AS THE SHORTWAVE
AXIS/SURFACE LOW APPROACH...WOULD EXPECT INCREASING TSTM ACTIVITY
ACROSS SE PA/DE/S NY TO LIFT INTO THE LOWER HUDSON VALLEY...NE
NJ...NYC METRO AND SW CT THIS EVENING.
WITH MARGINAL TO MODERATE INSTABILITY ACROSS OUR FAR WESTERN AREAS
AREA...MODEST SHEAR...AND INCREASING HELICITY A FEW STRONG TO SEVERE
STORMS ARE POSSIBLE THROUGH THIS EVENING...MAINLY WEST OF THE HUDSON
RIVER. THE LIMITING FACTOR WILL BE WANING INSTABILITY...BUT COULD BE
OVERCOME BY INCREASING SYNOPTIC SUPPORT. STRONG WINDS WOULD BE THE
MAIN SEVERE THREAT...BUT CAN NOT RULE OUT AN ISOLATED WEAK TORNADO
WITH ANY ROTATING STORMS. BASED ON PWATS AROUND 2 INCHES...GOOD
SYNOPTIC SUPPORT...AND WIND FIELDS INDICATIVE OF TRAINING
CELLS...MAIN OVERALL THREAT CONTINUES TO BE FLASH
FLOODING...WHICH SHOULD PEAK THIS EVENING ACROSS THE WESTERN 1/2 OF
THE CWA.
THEN AS THE SYNOPTIC FORCING CONTINUES TO PUSH EAST LATE THIS EVENING
INTO THE OVERNIGHT...THE THREAT FOR HEAVY SHOWERS AND TSTMS WILL
LIKELY SHIFT EAST ACROSS LI AND CT...WITH THE THREAT FOR URBAN FLASH
FLOODING DIMINISHING TO THE WEST.
THERE IS SOME UNCERTAINTY IN HOW WIDESPREAD HEAVY SHOWER/TSRA
ACTIVITY WILL BE ACROSS LI AND CT OVERNIGHT. DUE TO THE WEAKENING OF
THE SURFACE TROUGH AS THE SHORTWAVE SHEARS NW...THERE WILL BE NO
CLEAR CUT CONVERGENCE BOUNDARY TO FOCUS CONVECTION. WITH THIS
SAID THE SHRA/TSTM ACTIVITY COULD BE MORE STREAKY IN NATURE ACROSS
LI/CT TONIGHT...WITH FRICTIONAL CONVERGENCE LOCALLY ENHANCING
ACTIVITY. THIS IS SUPPORTED BY SOME OF THE HIGH RES MODEL OUTPUT.
WITH DEEP MOISTURE AXIS ADVECTING OVER THE REGION...MARGINAL
INSTABILITY...AND STRONG LLJ SUPPORT...THE FLASH FLOODING THREAT
WILL EXIST WHERE THESE RAIN BANDS DEVELOP...BUT COVERAGE MAY NOT
BE AS WIDESPREAD AS ACROSS WESTERN PORTIONS OF THE AREA.
HEAVIEST RAIN SHOWER/TSRA ACTIVITY LIKELY PUSHES EAST OF THE REGION
BY DAYBREAK AS SHORTWAVE AND LLJ PIVOT N AND E.
SEE HYDROLOGY SECTION FOR MORE ON FLOODING THREAT.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
THE GREAT LAKES UPPER LOW CONTINUES TO DEEPEN INTO THE NORTHEAST
DURING THIS TIME PERIOD.
DRYING CONDITIONS ARE LIKELY FRIDAY MORNING ACROSS WESTERN SECTIONS
IN THE WAKE OF THE SHORTWAVE...WITH PARTIAL CLEARING. FAR EASTERN
SECTIONS WILL LIKELY SEE MORE IN THE WAY OF CLOUD COVER...AS THEY
WILL BE ON THE FRINGE OF THE TROPICAL CONVEYOR BELT.
TIMING OF SHORTWAVES AROUND THE UPPER LOW WILL DETERMINE EXACT
TIMING OF ADDITIONAL SHRA/TSRA ACTIVITY FRI AFT/FRI NIGHT...BUT
HIGHEST PROBABILITY WILL LIKELY BE ACROSS INTERIOR FRI AFT/EVE WITH
DIURNAL HEATING.
FLASH FLOOD THREAT APPEARS TO BE LOWER ON FRIDAY AS PWATS DROP TO
1.25 TO 1.5 INCHES IN THE WAKE OF THE SHORTWAVE. MARGINAL
INSTABILITY AND SHEAR ALSO INDICATE THAT STRONG TO SEVERE STORMS
WOULD BE ISOLATED...BUT THIS WILL ULTIMATELY BE DETERMINED BY
STRENGTH OF THE NEXT SHORTWAVE AND AMOUNT OF HEATING.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
UNSETTLED...MUGGY AND WARM CONDITIONS WILL BE THE RULE FOR MUCH OF
THE PERIOD AS AN UPPER TROF OVER THE NE AND OH VALLEY STATES THIS
WEEKEND CLOSES OFF AND RETROGRADES TOWARD THE MID SECTION OF THE
COUNTRY BY THE MIDDLE OF NEXT WEEK. THE AIRMASS WILL BECOME LOADED
WITH MOISTURE AS A DEEP-LAYERED S/SW FLOW BECOMES ESTABLISHED
BETWEEN THE RIDGE OVER THE WESTERN ATLANTIC AND THE UPPER TROF. THE
BEST CHANCE FOR ORGANIZED HEAVY RAINFALL WILL BE ON SUNDAY AS LOW
PRESSURE OVER THE TN AND OH VALLEYS LIFTS NORTH...SENDING A
STATIONARY FRONT JUST SOUTH AND EAST OF THE AREA NORTHWARD AS A WARM
FRONT. PW VALUES WILL BE AROUND 2 INCHES. THIS LOOKS TO BE A MAINLY
HEAVY RAINFALL EVENT AS WIND SHEAR IS MARGINAL AND THE AIRMASS IS
WARM ALOFT. SCT STRONG AND/OR SEVERE CONVECTION IS A POSSIBILITY SAT
AFT/EVE...PRIMARILY NORTH AND WEST OF NYC...WHERE DEEP-LAYERED SHEAR
WILL EXIST WITH THE RRQ OF THE UPPER JET LIFTING ACROSS THE HUDSON
VALLEY. A LIMITING FACTOR ON SAT WILL BE A BRIEF DRYING OUT OF THE
AIRMASS.
EARLY NEXT WEEK...WITH THE FRONTAL BOUNDARY NORTH OF THE REGION AND
THE AREA IN WARM SECTOR...CONVECTION LOOKS TO BE MAINLY DIURNAL IN
NATURE. MON MAY STILL REMAIN WET AS MODEL SOLUTIONS DIVERGE WITH
THE LOCATION OF THE BOUNDARY. THE 12Z ECMWF IS ACTUALLY WETTER ON
MON THAN SUN...A COMPLETE OPPOSITE OF THE GFS...BUT THIS IS DUE TO A
SLOWER TIMING OF THE FRONTAL WAVE.
KEEP IN MIND AN AIRMASS THIS MOIST AND UNSTABLE WILL TRIGGER
ISOLATED TO SCT CONVECTION ALMOST ANYTIME AND IT WILL NOT TAKE MUCH
FOR SOME ORGANIZATION OF CLUSTERS TO FORM POCKETS OF HEAVY RAINFALL.
THIS IS ESPECIALLY THE CASE SUN INTO MON.
AS FOR TEMPS...LOOKING AT BOTH HIGHS AND LOWS RUNNING A FEW DEGREES
ABOVE NORMAL. SHOULD THE AMOUNT OF CLOUD COVER FROM CONVECTION BE
LESS...DAYTIME HIGHS COULD BE SEVERAL DEGREES WARMER THAN CURRENTLY
FORECAST. GENERALLY LOOKING FOR HIGHS 80 TO 85...AND LOWS IN THE
UPPER 60S TO LOWER 70S.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
LOW PRESSURE APPROACHES FROM THE WEST AND MOVES TO THE NORTHWEST
TONIGHT.
MOSTLY VFR EXCEPT KGON. WIND DIRECTIONS ARE GENERALLY OUT OF THE
ESE-SE. SPEEDS WILL BE FROM 8 TO 12 KT. AN OCCASIONAL GUST TO 15 KT
CANNOT BE RULED OUT AT CITY TERMINALS THROUGH EARLY EVENING.
THE LIKELIHOOD FOR SHOWERS AND THUNDERSTORMS OCCURS THIS EVENING AND
CONTINUES THROUGH 05/06Z. MOSTLY SHOWERS ANTICIPATED AFTER THIS
TIME...BUT AN ISOLATED THUNDERSTORM REMAINS A POSSIBILITY BUT NOT
MENTIONED IN TAFS.
CIGS WILL LOWER TO MVFR OR IFR LATE TONIGHT AND COULD CONTINUE INTO
EARLY FRIDAY MORNING. LOW CONFIDENCE IN THE TIMING OF IMPROVEMENTS
TO VFR AFTER SUNRISE. WINDS ALSO BEGIN TO SHIFT TO THE SW.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KEWR FCSTER COMMENTS: AMENDMENTS POSSIBLE THIS EVENING FOR
DEVELOPING SHOWERS AND THUNDERSTORMS. AN OCCASIONAL GUST TO 15 KT
POSSIBLE THROUGH EARLY EVENING.
KJFK FCSTER COMMENTS: AMENDMENTS POSSIBLE THIS EVENING FOR
DEVELOPING SHOWERS AND THUNDERSTORMS. CIGS COULD VARY BETWEEN MVFR
AND VFR. AN OCCASIONAL GUST TO 15 KT POSSIBLE THROUGH EARLY EVENING.
KLGA FCSTER COMMENTS: AMENDMENTS POSSIBLE THIS EVENING FOR
DEVELOPING SHOWERS AND THUNDERSTORMS. AN OCCASIONAL GUST TO 15 KT
POSSIBLE THROUGH EARLY EVENING.
KTEB FCSTER COMMENTS: AMENDMENTS POSSIBLE THIS EVENING FOR
DEVELOPING SHOWERS AND THUNDERSTORMS. AN OCCASIONAL GUST TO 15 KT
POSSIBLE THROUGH EARLY EVENING.
KHPN FCSTER COMMENTS: AMENDMENTS POSSIBLE THIS EVENING FOR
DEVELOPING SHOWERS AND THUNDERSTORMS.
KISP FCSTER COMMENTS: AMENDMENTS POSSIBLE THIS EVENING FOR
DEVELOPING SHOWERS AND THUNDERSTORMS. CIGS COULD VARY BETWEEN MVFR
AND VFR INTO THIS EVENING.
.OUTLOOK FOR 18Z FRI THROUGH TUESDAY...
.FRI-TUE...SUB VFR POSSIBLE AT TIMES WITH PERIODS OF SHOWERS
AND TSTMS.
&&
.MARINE...
A STRENGTHENING SOUTHERLY FLOW IS EXPECTED TO DEVELOP MARGINAL SCA
SEAS OVER THE OCEAN WATERS TONIGHT. MARGINAL SCA GUSTS ARE POSSIBLE
AS A LOW LEVEL JET MOVES OVER THE AREA TONIGHT...AND PASSES EAST
FRIDAY MORNING.
S/SW FLOW CONTINUES THROUGH FRIDAY NIGHT...BUT WINDS ARE EXPECTED TO
BE BELOW SCA LEVELS. SCA SOUTHERLY SWELLS SHOULD CONTINUE THROUGH.
HAVE CONTINUED TO UNDERCUT WNA GUIDANCE BY 1-2 FT BASED ON GUIDANCE
TREND AND ITS PERFORMANCE THIS SUMMER.
POTENTIAL EXISTS FOR AN EXTENDED PERIOD OF HAZARDOUS OCEAN SEAS VIA
PERSISTENT LONG FETCH SOUTHERLY FLOW. WINDS ARE EXPECTED TO STAY
BELOW CRITERIA. UNDERCUT WAVEWATCH BY A ABOUT A FOOT ON THE OCEAN
WATERS FOR MUCH OF THE PERIOD.
&&
.HYDROLOGY...
PATTERN INTO TONIGHT CONTINUES TO LOOK CONDUCIVE TO BANDS OF HEAVY
RAIN SHOWERS AND THUNDERSTORMS TRAINING OVER THE SAME AREA...WHICH
WOULD CAUSE URBAN AND SMALL STREAM FLASH FLOODING.
ON AVERAGE 1/2 TO 1 1/2 INCHES OF RAINFALL EXPECTED ACROSS LI AND
CT...WITH 1 1/2 TO 2 1/2 INCHES OF RAINFALL ACROSS NE NJ AND THE
LOWER HUDSON VALLEY. THE HIGHER AMOUNTS IN BOTH AREAS WILL BE TO
THE N AND W.
LOCALLY HIGHER AMOUNTS ARE LIKELY IN THE PATH OF TRAINING ACTIVITY.
RAINFALL RATES OF 2 TO 3 INCHES PER HOUR HAVE BEEN OBSERVED WITH THE
STRONGER THUNDERSTORMS THIS AFTERNOON. NEEDLESS TO SAY IF THIS TYPE
OF ACTIVITY TRAINS OVER AN AREA FOR AN HOUR...URBAN AND SMALL
STREAM FLASH FLOODING WILL OCCUR.
THE MAIN THREAT FOR URBAN FLASH FLOODING LOOKS TO BE THROUGH 06Z
ACROSS THE WESTERN 1/2 OF THE CWA...AND THROUGH AROUND DAYBREAK
ACROSS LI/CT. SMALL STREAMS COULD CONTINUE RISING INTO FRIDAY
MORNING. MEANWHILE...MAIN STEM RIVERS WILL SEE RISES...BUT THEY
ARE EXPECTED TO REMAIN WELL WITHIN THEIR BANKS. WITH SOME
UNCERTAINTY ON THE EVOLUTION OF CONVECTION ON FRIDAY...WILL
CONTINUE FLASH FLOOD WATCH UNTIL 6 PM FRIDAY AND LET SUBSEQUENT
SHIFTS TAKE DOWN IF NEEDED.
ADDITIONAL BOUTS OF HEAVY SHOWERS AND THUNDERSTORMS ARE POSSIBLE
THIS WEEKEND INTO EARLY NEXT WEEK...POSING ADDITIONAL THREATS FOR
FLOODING.
FOR DETAILS ON SPECIFIC AREA RIVERS AND STREAMS...INCLUDING
OBSERVED AND FORECAST RIVER STAGES...PLEASE VISIT THE ADVANCED
HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...FLASH FLOOD WATCH THROUGH FRIDAY AFTERNOON FOR CTZ005>012.
NY...FLASH FLOOD WATCH THROUGH FRIDAY AFTERNOON FOR NYZ067>075-
078>081-176>179.
NJ...FLASH FLOOD WATCH THROUGH FRIDAY AFTERNOON FOR NJZ002-004-006-
103>108.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT SATURDAY FOR ANZ350-353-
355.
&&
$$
SYNOPSIS...NV
NEAR TERM...JMC/NV
SHORT TERM...NV
LONG TERM...DW
AVIATION...JC/DS
MARINE...NV/DW
HYDROLOGY...NV/DW
AREA FORECAST DISCUSSION
NWS ALBANY NY
135 PM EDT WED JUN 26 2013
.SYNOPSIS...
MAINLY CLOUDY CONDITIONS WILL CONTINUE THROUGH THE
AFTERNOON AND INTO THE EVENING WITH SHOWERS AND THUNDERSTORMS. SOME
OF THE THUNDERSTORMS COULD PRODUCE HEAVY RAINFALL. A LOW PRESSURE
SYSTEM WILL BRING A WIDESPREAD HEAVY RAINFALL AND SOME THUNDERSTORMS
TO THE REGION LATE THURSDAY THROUGH FRIDAY. UNSETTLED WEATHER WILL
CONTINUE INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 135 PM EDT...VISIBLE SATELLITE IMAGERY SHOWS WIDESPREAD
CLOUDS ACROSS THE CWA EARLY THIS AFTERNOON. LOOKING AT KENX
RADAR...THERE CURRENTLY IS ONE BATCH OF MODERATE RAIN SHOWERS
ACROSS THE LAKE GEORGE AREA...WITH LOCALLY OVER AN INCH OF RAIN
ALREADY HAVING FALLEN FROM THIS ACTIVITY. MEANWHILE...THE
REMAINDER OF THE REGION IS FAIRLY QUIET...WITH JUST SOME SCT LIGHT
RAIN SHOWERS.
A WEAK SHORTWAVE WILL BE PASSING ACROSS THE REGION THIS AFTERNOON
INTO THIS EVENING...WHICH MAY ENHANCE THE CURRENT SHOWER/TSTM
ACTIVITY. THE 15Z HRRR SHOWS A BROKEN LINE OF SHOWERS AND
THUNDERSTORMS MOVING SOUTHEAST ACROSS CENTRAL AND SOUTHERN PARTS
OF THE CWA FOR THE LATE AFTN INTO THE EVENING HOURS.
WITH THE CLOUD COVER IN PLACE...INSTABILITY WILL BE LIMITED THIS
AFTERNOON. HOWEVER...PWATS REMAIN HIGH...WITH A READING AROUND
1.75 INCHES FOR ALBANY BASED ON THE 12Z KALY SOUNDING AND 12Z
BUFKIT MODEL SOUNDINGS FOR KALB. LATEST SFC OBS SHOW DEWPOINTS IN
THE UPPER 60S TO LOW 70S...SO ANY THUNDERSTORM WILL BE CAPABLE OF
HVY RAINFALL. THE SEVERE THREAT MAY BE LIMITED DUE TO CLOUD
COVER/LIMITED INSTABILITY...BUT SPC MAINTAINS A SLIGHT RISK OVER
MUCH OF THE REGION. THE MAIN THREAT TODAY IS PROBABLY HEAVY
RAINFALL AND POTENTIAL LOCALIZED FLOODING...ALTHOUGH A ROGUE
SEVERE WIND GUST OR MARGINAL SEVERE HAIL CANNOT TOTALLY BE RULED
OUT...ESP IF SOME BREAKS IN THE CLOUDS WERE TO OCCUR.
WITH THE CLOUDS IN PLACE...MAX TEMPS WILL BE HELD DOWN...ESP
COMPARED TO RECENT DAYS. MAX TEMPS IN THE UPPER 70S TO MID 80S ARE
EXPECTED...WITH THE WARMEST READINGS ACROSS THE SOUTHEASTERN PART
OF THE CWA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
TONIGHT...THE SHOWERS AND THUNDERSTORMS SHOULD DIMINISH OVER THE
SRN PORTION QUICKLY EARLY THIS EVENING WITH A WEAK MICRO RIDGE
BUILDING IN OVER NY AND PA. THE SFC HIGH WILL NUDGE IN FROM SE
ONTARIO...AND THE ERN GREAT LAKES REGION. A PARTIAL CLEARING OVER
THE NRN PORTION OF THE FCST AREA WILL ALLOW PATCHY FOG TO FORM
AGAIN WITH LIGHT WINDS AND MOISTURE IN THE BOUNDARY LAYER. LOW
TEMPS IN THE LOWER TO MID 60S WILL BE COMMON...WITH PERHAPS SOME
U60S IN THE VALLEYS. WEAK WARM ADVECTION COMMENCES OVER THE SRN
TIER AHEAD OF A WARM FRONT/THERMAL TROUGH...AS A LOW PRESSURE
SYSTEM WITH STRONG SHORT-WAVE TROUGH APPROACHES FROM THE OHIO
VALLEY AND THE LOWER GREAT LAKES REGION TOWARDS 12Z/THU. THE
SHOWALTER VALUES LOWER TO -1C NEAR THE MID HUDSON VALLEY...SO A
SLIGHT OR LOW CHC OF SHOWERS AND THUNDERSTORMS WAS INCLUDED
TOWARDS DAYBREAK.
THU-THU NIGHT...ANOTHER ACTIVE STRETCH OF WX AS THE POTENT SHORT-
WAVE TROUGH SWINGS TOWARD THE REGION WITH A SFC CYCLONE LIFTING
NORTHWARD FROM PA INTO W-CNTRL NY IN THE AFTERNOON. THE ISENTROPIC
LIFT INCREASES AHEAD OF THE WARM FRONT FOR SHOWERS AND SCT
THUNDERSTORMS TO INCREASE FROM SOUTH TO NORTH DURING THE
AFTERNOON. THE PLACEMENT OF THE WARM SECTOR IS NEBULOUS
STILL...AND PERHAPS THE SRN MOST ZONES MAY GET INTO ONE BEFORE
SUNSET. THE AMOUNTS OF INSTABILITY LOOKS VARIABLE ON THE GUIDANCE
AND THE LOW-LEVEL JET DOES NOT CRANK UP UNTIL NIGHTFALL /30-40 KTS
AT H850/. THE GFS DOES SHOW A BRIEF PERIOD OF MLCAPES OF 500-1500
J/KG IN THE AFTERNOON OVER THE SRN MOST ZONES. AGREE WITH SPC THAT
5% WIND PROBABILITIES LOOK GOOD AT THIS POINT FOR A FEW STRONG TO
MAYBE SEVERE THUNDERSTORMS. THE QG LIFT STRENGTHENS ON THE NORTH
SIDE OF THE SFC WAVE AND AHEAD OF THE WARM FRONT. USED THE WEATHER
PHRASING AS RAIN HEAVY AT TIMES WITH A CHC OF THUNDERSTORMS WITH
SHOWALTER VALUES OF 0 TO -2C...ESPECIALLY AT NIGHT.
PWATS WILL BE RUNNING A FEW STANDARD DEVIATIONS ABOVE NORMAL FOR
SOME VERY HEAVY RAINFALL POSSIBLE. A FLASH FLOOD OR FLOOD WATCH MAY
BE NEEDED LATER IN TIME. THE WPC QPF WAS ACCEPTED WITH 1-2+ INCHES
OF RAINFALL POSSIBLE THU-THU NIGHT OVER THE FCST AREA. THE HEAVIEST
RAINFALL LOOKS LIKE IT WILL BE OVER THE SRN DACKS REGION AND MOHAWK
VALLEY. WPC ALSO HAS A SLIGHT RISK OF FLASH FLOODING FOR THE FCST
AREA. THE ECMWF AND GFS QPF LOOK CLOSER TO WPC THAN THE NAM. THE
HEAVIEST RAIN AXIS APPEARS IT WILL BE OVER W-CNTRL NY. NO POINTS ARE
FORECASTED TO FLOOD ON THE MAIN STEM RIVERS AT THIS TIME.
CATEGORICAL AND LIKELY POPS WERE USED IN THE PM AND NIGHT TIME
PERIOD. MAX TEMPS IN THE 70S TO L80S WILL BE COMMON WITH LOWS IN THE
60S.
FRIDAY...FOLLOWED THE GFS/ECMWF WHERE A DRY SLOT TO THE SYSTEM MAY
SHUT THE RAINFALL OFF IN THE LATE MORNING...ESPECIALLY OVER THE
SRN TWO THIRDS OF THE FCST AREA. SMALL AMOUNTS OF
INSTABILITY...AND POSSIBILITY OF A LITTLE SUN STILL WARRANTED A
CHANCE OF THUNDERSTORMS. THE SFC WAVE WILL BE OVER SRN QUEBEC
WITH A FRONTAL BOUNDARY STALLING NEAR THE REGION. ANOTHER IMPULSE
ROUNDING THE BASE OF THE TROUGH COULD REKINDLE THE SHOWERS IN THE
AFTERNOON. THE GFSMOS MAX TEMPS WERE FAVORED AGAIN.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
THE WEATHER PATTERN WILL BE A VERY HUMID AND UNSETTLED DURING THE
LONG TERM PERIOD. THE MEDIUM RANGE MODELS INDICATE THAT A DEEP TROF
WILL SET UP ACROSS THE MIDDLE OF THE COUNTRY WHILE A LARGE UPPER
LEVEL RIDGE WILL BUILD OVER THE WESTERN ATLANTIC OFF THE MID
ATLANTIC COAST. THIS WILL KEEP THE REGION IN A SOUTHWEST FLOW OF
VERY MOIST AIR THROUGH THE PERIOD WITH A STALLED FRONTAL BOUNDARY
SOMEWHERE ALONG THE EAST COAST. THIS SHOULD RESULT IN AT LEAST
SCATTERED SHOWERS AND TSTMS EACH DAY...WITH THE GREATEST COVERAGE
OCCURRING DURING THE AFTN AND EVENING. ALTHOUGH SOME SHORT WAVE
TROFS MAY EVENTUALLY RIDE ALONG THIS SOUTHWEST FLOW OF MOIST AIR AND
PROVIDE ADDITIONAL FOCUS TO THE CONVECTION/PCPN...MODELS ARE NOT
INDICATING ANY OBVIOUS SYSTEMS AT THIS TIME...SO PREFERRED TO KEEP
POPS IN THE CHANCE RANGE (40 TO 50 PERCENT) DURING THE ENTIRE LONG
TERM PERIOD AND LATER FORECAST CAN REFINE PERIOD WHERE POPS MAY NEED
TO BE HIGHER.
ALTHOUGH THIS TYPE OF PATTERN FREQUENTLY RESULTS IN VERY WARM OR HOT
TEMPS...FAIRLY WIDESPREAD CLOUD COVER AND OCNL PCPN WILL KEEP HIGH
TEMPS IN THE MID 70S TO LOWER 80S SATURDAY THRU TUESDAY. HOWEVER...
DEWPOINTS IN THE 60S WILL MAKE IT FEEL UNCOMFORTABLE. LOW TEMPS WILL
BE WARM WITH LOWS IN THE UPPER 50S AND 60S FRIDAY NIGHT THROUGH
MONDAY NIGHT.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
A WEAK SURFACE/UPPER LEVEL TROF WILL MOVE ACROSS THE TAF SITES INTO
THIS EVENING. AN AREA OF SHOWERS HAS BEEN AFFECTING KGFL WITH MVFR
CONDITIONS...AND AN MVFR CEILING IS AFFECTING KPSF. AN AREA OF
SHOWERS SHOULD EXIT THE KGFL AREA BETWEEN 19Z-21Z...WHILE LIGHTER
SHOWERS DEVELOP AND TRACK TOWARD KALB AND KPSF. THE SCATTERED
NATURE TO THE SHOWERS SUGGESTS PUTTING VCSH AT THOSE SITES THIS
AFTERNOON. SOME SCATTERED THUNDERSTORM ACTIVITY COULD DEVELOP
TOWARD KPOU BUT AGAIN SCATTERED NATURE SUGGESTS VCSH UNTIL ACTUAL
THUNDERSTORM DEVELOPMENT WHEN AMENDMENTS MAY BE NEEDED.
ALL SHOWER AND THUNDERSTORM ACTIVITY SHOULD END THIS EVENING AND
SOME CLEARING SHOULD TAKE PLACE...WITH JUST SCATTERED CLOUDS THIS
EVENING. FOG IS LIKELY TO DEVELOP AFTER MIDNIGHT AND CONTINUE
THROUGH ABOUT 14Z...WITH SOME LOW CEILINGS POTENTIALLY DEVELOPING
ALONG WITH THE FOG. ANY FOG AND LOW CLOUDS SHOULD LIFT BY 14Z...AND
VFR CONDITIONS SHOULD PREVAIL AT ALL THE SITES THROUGH THE REST OF
TOMORROW MORNING.
WINDS SHOULD BE LIGHT SOUTH TO SOUTHWEST THIS AFTERNOON...AND
NEARLY CALM TONIGHT. WINDS SHOULD BE VARIABLE TO LIGHT SOUTH AT 6
KT OR LESS TOMORROW MORNING.
OUTLOOK...
THU-FRI...VFR/MVFR. SHOWERS LIKELY W/CHC -TSRAS.
SAT-MON ...VFR/MVFR IN CHC -SHRAS/-TSRAS.
&&
.FIRE WEATHER...
ANOTHER DISTURBANCE TODAY WILL FOCUS ANOTHER
ROUND OF ISOLATED TO SCATTERED THUNDERSTORMS WITH WARM AND HUMID
CONDITIONS PREVAILING. SOME OF THE THUNDERSTORMS COULD BE STRONG TO
SEVERE WITH VERY HEAVY RAINFALL. A LOW PRESSURE SYSTEM WILL BRING A
WIDESPREAD POTENTIALLY HEAVY RAINFALL AND SOME STRONG THUNDERSTORMS
TO THE REGION THURSDAY THROUGH FRIDAY.
HIGH RH VALUES AND WET CONDITIONS WILL PERSIST FOR THE NEXT
SEVERAL DAYS...AND THEIR WILL BE NO FIRE WEATHER ISSUES.
&&
.HYDROLOGY...
THE UNSETTLED WEATHER CONTINUES...AS THE WEEK PROGRESSES WITH
A POTENTIAL POTENT STORM IMPACTING THE REGION LATE THURSDAY INTO
FRIDAY.
FIRST...THE SHOWERS AND THUNDERSTORMS WILL HAVE THE POTENTIAL TO
PRODUCE LOCALLY HEAVY RAINFALL TODAY. SOME TRAINING OF THE CELLS
WILL HAVE TO BE MONITORED THIS AFTERNOON INTO TONIGHT.
PONDING OF WATER ON ROADWAYS ALONG WITH MINOR FLOODING OF LOW LYING
AND POOR DRAINAGE AREAS IS EXPECTED WITH THE HEAVY RAINFALL. ALSO
SOME SMALL STREAMS...CREEKS...AND BROOKS MAY REACH BANKFULL OR EVEN
FLOODING QUICKLY ESPECIALLY IF STORMS MOVE OVER THE SAME AREA
REPEATEDLY.
THE RAINFALL FROM THE LOW PRESSURE SYSTEM AND ITS WARM FRONT
THURSDAY INTO FRIDAY MORNING COULD PRODUCE 1 TO 2 INCHES OF
RAINFALL WITH LOCALLY HIGHER AMOUNTS. THE WPC QPF WAS USED IN THIS
TIME FRAME. A FLASH FLOOD WATCH OR FLOOD WATCH MAY BE NEEDED IF
THE POTENTIAL FOR WIDESPREAD FLOODING LOOKS LIKELY.
MORE SHOWERS AND THUNDERSTORMS ARE EXPECTED FRIDAY THROUGH THE
WEEKEND WHICH WILL ALLOW SOILS TO BECOME MORE SATURATED AND
INCREASES THE POTENTIAL RISK OF FLOODING.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS/NAS/WASULA
NEAR TERM...FRUGIS
SHORT TERM...WASULA
LONG TERM...SNYDER
AVIATION...NAS
FIRE WEATHER...WASULA
HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1014 AM EDT WED JUN 26 2013
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OFF THE EAST COAST AND ACROSS THE ATLANTIC
OCEAN INTO NEXT WEEK. A LEE SIDE TROUGH WILL REMAIN ACROSS THE AREA
TODAY INTO TONIGHT. AN AREA OF LOW PRESSURE WILL MOVE OUT OF THE
OHIO RIVER VALLEY AND INTO THE NORTHEAST THURSDAY INTO THURSDAY
NIGHT, BRINGING A SLOW MOVING COLD FRONT INTO THE AREA THAT WILL
LIKELY STALL OUT ALONG THE EAST COAST INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
CHALLENGING DAY AHEAD... THE 12Z IAD SOUNDING IS HOT...96F FULL SUN.
CONVECTIVELY IT LOOKS A LITTLE DRY AND AT 93/66...DOESN`T FIRE STORMS.
FURTHER NORTH WHERE NO ACTUAL SOUNDING...WE PRESUME MORE UNSTABLE...
ESPECIALLY BENEATH A MODELED SHORT WAVE TRANSLATING EWD ALONG AND
N OF 40N THRU PA/NJ THIS AFTN.
WILL ADJUST TEMPS SLIGHTLY THE NEXT SEVERAL HOURS UNDER HEAVIER
MID MORNING CLOUD COVER NE PA AND NNJ.
HEAT ADVISORY: MAY DISCONTINUE AT 1115 AM. SFC DEWPOINTS ARE ABOUT
3-4F LESS THAN 24 HOURS AGO AND SO WITH A MAX TEMP PROJECTED AROUND
93F...MAX HI 96. NOT QUITE OUR CRITERIA OF 98 IN LATE JUNE.
CONVECTIVELY... THE 13Z RAP HAS SCT TSTMS BREAKING OUT IN THE NW
1/3 RD OF OUR AREA AROUND 21Z VIA THE MORE RELIABLE STABLE PCPN
OUTPUT. RAP CONVECT BEGINS 1-2 HOURS SOONER. 1355Z COSPA GIVE PHL
TIL AT LEAST 19Z BEFORE CONVECTION DEVELOPS ON ITS DOORSTEP. COSPA
STILL DEVELOPS A LARGE AREA OF BANDED HEAVY CONVECTION IN SE PA
BETWEEN 20-22Z.
12Z NAM LOOKS LIT UP A LITTLE EARLY AT 18Z AND SO THAT AFFECTS ITS
SFC TEMP FCST WHICH IS STILL 90 AT 18Z AT KPHL.
MLCAPE HAS ABOUT 2000 J THIS AFTN. BULK SHEAR LOOKS WEAK BUT AS
PER YDY... ISOLATED SVR ARE POSSIBLE IN THE MID-UPPER 90S HEAT
INDEX REGION WITH PLENTY OF CAPE.
TONIGHT...CONVECTION DIMINISHES SEWD THRU S NJ AND DELMARVA AROUND
02-04Z AND ANOTHER FAIR HUMID HAZY NIGHT IS IN STORE.
&&
.SHORT TERM /THURSDAY/...
HEAVY CONVECTION EXPECTED IN THE AFTN OR EARLY AT NIGHT WITH AN
APPROACHING TROUGH AND LOWERING SFC PRES. KI IS MORE WIDESPREAD
THAN THAT OF TODAY.
MAX TEMPS AROUND 2F LOWER THAN THOSE OF TODAY AND SO STILL A
SMALL CHANCE OF 90F FOR S NJ AND THE PHL AREA SOUTHWESTWARD...
DEPENDENT ON CLOUD COVER AND PCPN PRIOR TO 18Z.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
BY THURSDAY, THE LEE SIDE TROUGH WILL GET SQUEEZED OUT AS AN AREA OF
LOW PRESSURE MOVES OUT OF THE OHIO RIVER VALLEY AND INTO THE
NORTHEAST THURSDAY INTO THURSDAY NIGHT, WHILE BRINGING A COLD FRONT
ACROSS. THIS LOW PRESSURE WILL DRIFT NORTHWARD THROUGH THE NORTHEAST
AND INTO CANADA FRIDAY INTO THE WEEKEND. THE AFOREMENTIONED FRONT
WILL LIKELY STALL ALONG THE EAST COAST INTO THE WEEKEND. A LONG WAVE
TROUGH LOOKS TO DEVELOP FROM EASTERN CANADA, THROUGH THE GREAT LAKES
AND INTO BUILD DOWN INTO THE CENTRAL GULF STATES DURING THE WEEKEND
INTO EARLY NEXT WEEK. THIS WILL KEEP A SOUTHWEST FLOW ACROSS THE
AREA FOR A PROLONGED PERIOD. WITH THE FRONTAL BOUNDARY NEAR THE AREA
AND PERIODIC SHORT WAVES/VORT MAX IMPULSES EMBEDDED IN THE CYCLONIC
FLOW, THIS WILL BE A FAIRLY UNSETTLED WEATHER PATTERN. EACH PERIOD
WILL HAVE CHANCE/LIKELY POP, AND WITH THE WARM, UNSTABLE AIRMASS,
THUNDERSTORMS WILL BE POSSIBLE EACH DAY AS WELL. PW VALUES WILL
REMAIN HIGH, AROUND 1.5-2 INCHES, SO HEAVY RAIN WILL BE A CONCERN.
TEMPERATURES WILL REMAIN FAIRLY WARM AND ARE EXPECTED TO BE A FEW
DEGREES ABOVE NORMAL EACH DAY, ALTHOUGH NOT AS WARM AS THE BEGINNING
OF THIS WEEK.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
TODAY...VFR SCT-BKN CLOUDS AOA 5000 FT. SW WIND G 15 KT. BANDS OF
TSTMS DEVELOP AFTER 18Z IN E PA WITH MOSTLY W-NW GUSTS 30-40 KT
AND BRIEF IFR CONDITIONS IN TSTMS.
TONIGHT...LEFTOVER CONVECTION DIES AND SO VFR SCT-BKN AOA 5000 FT.
POSSIBLE MVFR FOG HAZE LATE. LIGHT S-SW WIND. CONFIDENCE IN PRECIP/
CLOUDS TONIGHT IS LESS THAN AVERAGE.
THURSDAY...AFTER ANY EARLY MVFR HAZE...VFR SCT-BKN CLOUDS AOA 5000
FT WITH BANDS OF IFR TSTMS IN THE AFTN/EVENING GENERATING W WIND
GUSTS 30-40 KT.
OUTLOOK...
THURSDAY THROUGH SUNDAY...GENERALLY VFR WITH PERIODS OF MVFR/IFR
POSSIBLE EACH DAY WITH SHOWERS AND THUNDERSTORMS AND MORNING LOW
CLOUDS/FOG.
&&
.MARINE...
THE PRESSURE GRADIENT OVER THE WATERS TODAY WILL FAVOR A SW FLOW
WITH SPEEDS AROUND 10 TO 15 KNOTS. SEAS SHOULD REMAIN IN THE 3 TO 4
FT RANGE OUT OVER THE OCEAN WATERS AND 1 TO 2 FEET ON DEL BAY. WHILE
SCA CONDITION ARE NOT EXPECTED TODAY AND TONIGHT...TSTMS WITH GUSTY
WINDS ARE POSSIBLE THIS AFTERNOON AND TONIGHT. BE PREPARED FOR
HIGHER WINDS AND SEAS IN ANY TSTM. SMW`S MAY BE ISSUED LATER TODAY.
THURSDAY...THE SLY FLOW STRENGTHENS AHEAD OF THE APPROACHING TROUGH
AND DEEPENING SFC LOW INTO N PA AND S NYS. SCA SOUTHERLY FLOW SEAS
MAY REACH CRITERIA ON THE ATLC WATERS BUT THERE IS QUESTION
WHETHER THE WAA IS OVERFORECASTING THE SLY SWELL.
OUTLOOK...
SMALL CRAFT ADVISORY CONDITIONS MAY RETURN TO THE ATLANTIC COASTAL
WATERS INTO THE WEEKEND. SOUTHWEST WINDS ARE EXPECTED TO INCREASE
AHEAD OF AN APPROACHING COLD FRONT THAT WILL STALL ALONG THE EAST
COAST THROUGH THE WEEKEND. WINDS MAY PERIODICALLY GUSTA ROUND 25
KNOTS THROUGH THE PERIOD. ALSO, SEAS ARE FORECAST TO BUILD TO 5-6
FEET WITH THE SOUTHWESTERLY FLOW AS WELL.
&&
.RIP CURRENTS...
LOW RISK TODAY BUT NOT A NO RISK!! MARGINALLY LOW TOMORROW IN NJ
IF THE SLY SWELL BUILDS TO 4 FT WITH A 7 SEC PERIOD AND THE S WIND
AVERAGES 14 KT MIDDAY.
&&
.CLIMATE...
TEMPS BELOW...
PROJECTING AN ABOVE NORMAL MONTH FOR ALL STATIONS ON THE ORDER OF
1 TO 2 DEGREES EXCEPT A LITTLE LESS THAN A DEGREE ABOVE NORMAL AT
KACY.
PHL SPECIFICALLY PROJECTS 74.5 OR 1.3 ABOVE NORMAL. THE JUNE 1981-2010 AVG
IS 73.2.
JUNE RAINFALL BELOW..
KILG ALREADY RECORD MONTHLY RFALL AT 10.09
KPHL RANKED #2 AT 8.80 INCHES BEHIND THE 10.06 JUNE 1998 RECORD.
KACY RANKED #3 AT 7.20 BEHIND THE 7.57 IN 1935 AND RECORD JUNE
TOTAL OF 8.45 IN 1920.
KABE STILL RANKED 8TH WETTEST JUNE AT 6.48 INCHES. THE MONTHLY
RECORD IS 10.51 IN 1938.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR PAZ070-071-102-
104-106.
NJ...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NJZ015-017>019.
DE...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR DEZ001.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ROBERTSON
NEAR TERM...DRAG/O`HARA 1015
SHORT TERM...DRAG/O`HARA 1015
LONG TERM...ROBERTSON
AVIATION...DRAG/ROBERTSON/O`HARA 1015
MARINE...DRAG/ROBERTSON/O`HARA 1015
RIP CURRENTS...
CLIMATE...1015
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
914 AM EDT WED JUN 26 2013
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OFF THE EAST COAST AND ACROSS THE ATLANTIC
OCEAN INTO NEXT WEEK. A LEE SIDE TROUGH WILL REMAIN ACROSS THE AREA
TODAY INTO TONIGHT. AN AREA OF LOW PRESSURE WILL MOVE OUT OF THE
OHIO RIVER VALLEY AND INTO THE NORTHEAST THURSDAY INTO THURSDAY
NIGHT, BRINGING A SLOW MOVING COLD FRONT INTO THE AREA THAT WILL
LIKELY STALL OUT ALONG THE EAST COAST INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
CHALLENGING DAY AHEAD... THE 12Z IAD SOUNDING IS HOT...96F FULL SUN.
CONVECTIVELY IT LOOKS A LITTLE DRY AND AT 93/66...DOESN`T FIRE
STORMS. FURTHER NORTH WHERE NO ACTUAL SOUNDING...WE PRESUME MORE
UNSTABLE...ESPECIALLY BENEATH A MODELED SHORT WAVE TRANSLATING
EWD ALONG AND N OF 40N THRU PA/NJ THIS AFTN.
SO...THE HEAT ADVISORY CONTINUES AS THE POORLY MODELED W PA CONVECTION
CONTINUES TO FRITTER PERMITTING PLENTY OF SUN. KEEPING AN EYE ON
THE 1218Z CONVECTION NEAR KEKN BUT FOR NOW THINKING IT TENDS TO
WANE.
CONVECTIVELY... THE 10Z RAP HAS THE PCPN BREAKING OUT SUDDENLY IN
THE NW 1/3 RD OF OUR AREA AROUND 21Z VIA THE MORE RELIABLE STABLE
PCPN OUTPUT. RAP CONVECT BEGINS 1-2 HOURS SOONER. THE COSPA GIVE
PHL TIL 19Z BEFORE CONVECTION DEVELOPS ON ITS DOORSTEP. COSPA DEVELOPS
A LARGE AREA OF BANDED HEAVY CONVECTION IN SE PA BETWEEN 19-21Z.
MLCAPE HAS ABOUT 2000 J THIS AFTN. BULK SHEAR LOOKS WEAK BUT AS
PER YDY... ISOLATED SVR ARE POSSIBLE IN THE MID-UPPER 90S HEAT
INDEX REGION WITH PLENTY OF CAPE.
TONIGHT...CONVECTION DIMINISHES AND ANOTHER FAIR HUMID HAZY NIGHT
IS IN STORE.
&&
.SHORT TERM /THURSDAY/...
HEAVY CONVECTION EXPECTED IN THE AFTN OR EARLY AT NIGHT WITH AN
APPROACHING TROUGH. KI IS MORE WIDESPREAD THAN THAT OF TODAY.
MAX TEMPS AROUND 2F LOWER THAN THOSE OF TODAY AND SO STILL A
SMALL CHANCE OF 90F FOR S NJ AND THE PHL AREA SOUTHWESTWARD...
DEPENDENT ON CLOUD COVER AND PCPN PRIOR TO 18Z.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
BY THURSDAY, THE LEE SIDE TROUGH WILL GET SQUEEZED OUT AS AN AREA OF
LOW PRESSURE MOVES OUT OF THE OHIO RIVER VALLEY AND INTO THE
NORTHEAST THURSDAY INTO THURSDAY NIGHT, WHILE BRINGING A COLD FRONT
ACROSS. THIS LOW PRESSURE WILL DRIFT NORTHWARD THROUGH THE NORTHEAST
AND INTO CANADA FRIDAY INTO THE WEEKEND. THE AFOREMENTIONED FRONT
WILL LIKELY STALL ALONG THE EAST COAST INTO THE WEEKEND. A LONG WAVE
TROUGH LOOKS TO DEVELOP FROM EASTERN CANADA, THROUGH THE GREAT LAKES
AND INTO BUILD DOWN INTO THE CENTRAL GULF STATES DURING THE WEEKEND
INTO EARLY NEXT WEEK. THIS WILL KEEP A SOUTHWEST FLOW ACROSS THE
AREA FOR A PROLONGED PERIOD. WITH THE FRONTAL BOUNDARY NEAR THE AREA
AND PERIODIC SHORT WAVES/VORT MAX IMPULSES EMBEDDED IN THE CYCLONIC
FLOW, THIS WILL BE A FAIRLY UNSETTLED WEATHER PATTERN. EACH PERIOD
WILL HAVE CHANCE/LIKELY POP, AND WITH THE WARM, UNSTABLE AIRMASS,
THUNDERSTORMS WILL BE POSSIBLE EACH DAY AS WELL. PW VALUES WILL
REMAIN HIGH, AROUND 1.5-2 INCHES, SO HEAVY RAIN WILL BE A CONCERN.
TEMPERATURES WILL REMAIN FAIRLY WARM AND ARE EXPECTED TO BE A FEW
DEGREES ABOVE NORMAL EACH DAY, ALTHOUGH NOT AS WARM AS THE BEGINNING
OF THIS WEEK.
&&
.AVIATION /13Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
TODAY...VFR SCT-BKN CLOUDS AOA 5000 FT. SW WIND G 15 KT. BANDS OF
TSTMS DEVELOP AFTER 18Z IN E PA WITH MOSTLY W-NW GUSTS 30-40 KT
AND BRIEF IFR CONDITIONS IN TSTMS.
TONIGHT...LEFTOVER CONVECTION DIES AND SO VFR SCT-BKN AOA 5000 FT.
POSSIBLE MVFR FOG HAZE LATE. LIGHT S-SW WIND. CONFIDENCE IN PRECIP/CLOUDS
TONIGHT IS LESS THAN AVERAGE.
THURSDAY...AFTER ANY EARLY MVFR HAZE...VFR SCT-BKN CLOUDS AOA 5000
FT WITH BANDS OF IFR TSTMS IN THE AFTN/EVENING GENERATING W WIND
GUSTS 30-40 KT.
OUTLOOK...
THURSDAY THROUGH SUNDAY...GENERALLY VFR WITH PERIODS OF MVFR/IFR
POSSIBLE EACH DAY WITH SHOWERS AND THUNDERSTORMS AND MORNING LOW
CLOUDS/FOG.
&&
.MARINE...
THE PRESSURE GRADIENT OVER THE WATERS TODAY WILL FAVOR A SW FLOW
WITH SPEEDS AROUND 10 TO 15 KNOTS. SEAS SHOULD REMAIN IN THE 3 TO 4
FT RANGE OUT OVER THE OCEAN WATERS AND 1 TO 2 FEET ON DEL BAY. WHILE
SCA CONDITION ARE NOT EXPECTED TODAY AND TONIGHT...TSTMS WITH GUSTY
WINDS ARE POSSIBLE THIS AFTERNOON AND TONIGHT. BE PREPARED FOR
HIGHER WINDS AND SEAS IN ANY TSTM. SMW`S MAY BE ISSUED LATER TODAY.
THURSDAY...THE SLY FLOW TIGHTENS A BIT AHEAD OF THE APPROACHING
TROUGH AND THAT MAY BE ENOUGH TO DEVELOP SCA SOUTHERLY SWELL SEAS
BUT THERE IS QUESTION WHETHER THE WAA IS OVER FORECASTING THE SLY
SWELL.
OUTLOOK...
SMALL CRAFT ADVISORY CONDITIONS MAY RETURN TO THE ATLANTIC COASTAL
WATERS INTO THE WEEKEND. SOUTHWEST WINDS ARE EXPECTED TO INCREASE
AHEAD OF AN APPROACHING COLD FRONT THAT WILL STALL ALONG THE EAST
COAST THROUGH THE WEEKEND. WINDS MAY PERIODICALLY GUSTA ROUND 25
KNOTS THROUGH THE PERIOD. ALSO, SEAS ARE FORECAST TO BUILD TO 5-6
FEET WITH THE SOUTHWESTERLY FLOW AS WELL.
&&
.RIP CURRENTS...
LOW TODAY. MARGINALLY LOW TOMORROW IN NJ IF THE SLY SWELL BUILDS TO
4 FT WITH 7 SEC AND THE S WIND AVERAGES 14 KT MIDDAY.
&&
.CLIMATE...
PROJECTING AN ABOVE NORMAL MONTH FOR ALL STATIONS ON THE ORDER OF
1 TO 2 DEGS REES EXCEPT A LITTLE LESS THAN A DEGREE ABOVE NORMAL
AT KACY.
PHL SPECIFICALLY PROJECTS 74.5 OR 1.3 ABOVE NORMAL. THE JUNE AVG IS
73.2.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR PAZ070-071-102-
104-106.
NJ...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NJZ015-017>019.
DE...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR DEZ001.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ROBERTSON
NEAR TERM...DRAG/O`HARA 913
SHORT TERM...DRAG/O`HARA 913
LONG TERM...ROBERTSON
AVIATION...DRAG/ROBERTSON/O`HARA 913
MARINE...DRAG/ROBERTSON/O`HARA 913
RIP CURRENTS...913
CLIMATE...913
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
842 PM EDT Thu Jun 27 2013
.NEAR TERM [Rest of Tonight]...
Current satellite and radar analysis shows an MCS developing over
Central Georgia and Alabama. This MCS will propagate southward
overnight and increase our rain chances for our GA and AL
counties. Models disagree on the persistence of this MCS through
the overnight, with our local WRF and EastARW WRF showing a
persistent MCS that moves off the FL Panhandle in the pre-dawn
hours, and the HRRR showing a system that collapses a few hours
after sunset. The 00Z sounding shows ample CAPE above 3500 J/kg,
PWAT values at 1.89 in, and weak vertical wind shear. While we do
anticipate this system to weaken and propagate more to the SW as
current trends are showing, we do think the MCS will hold together
in some capacity, increasing rain chances for SW Georgia, SE
Alabama, and possibly the FL Panhandle. This MCS will be capable
of producing strong to severe storms with straight line winds
being the primary concern.
&&
.SHORT TERM [Friday Through Saturday Night]...
The mean upper trough axis is forecast to remain east of the
forecast area through Friday. This will lead to one more day of
northerly mid-level flow and the potential for convection to push
southward into the area late the afternoon or early in the
evening. The timing and location of this convection will be
tricky, as lingering early morning convection over the Florida
zones could influence development later in the day. High-res
guidance reflects this uncertainty, showing a variety of
evolutions for convection on Friday. With this uncertainty in
mind, have gone conservatively with high chance PoPs for most
locations Friday and Friday evening. With the expected late start
to convection once again, expect high temperatures to reach the
mid 90s for many locations.
By Saturday, the wetter pattern that has been advertised for
several days will begin to develop as the upper trough deepens and
retrogrades to the west. This will shift the deep layer flow to
the southwest with significantly deeper moisture in place. In
addition, a shortwave moving into the base of the trough will help
to enhance convective development as well. Will go with likely
PoPs for most of the area for Saturday, with highs only topping
out in the upper 80s to near 90.
&&
.LONG TERM [Sunday through Thursday]...
Unseasonably deep upper trough is forecast to continue slowly
retrograding through the middle of next week, keeping most of the
forecast area under the influence of a moist and unsettled
southwesterly deep layer flow. At the surface, a relatively
stationary frontal boundary will remain in place, roughly
bisecting the forecast area from northeast to southwest early in
the period, before sliding back to the west by the middle of the
week. Areas to the east of this boundary will have the greatest
potential for heavy rain, with lighter amounts expected west of
the boundary. Exactly where this boundary is on a day-to-day basis
remain uncertain, so have kept the PoP gradient somewhat broad,
with the highest PoPs (60s-70s) in the east and lower PoPs
(30-40s) in the west.
&&
.AVIATION...[Through 00Z Saturday]
There is still significant model discrepancy on the timing of the
line of thunderstorms currently moving through Central GA. Have
weighted forecast with our local WRF to reflect flight
restrictions later in the TAF period. The highest confidence in
thunderstorms occurring at all terminals is between 03-07Z,
bringing MVFR flight restrictions. During the afternoon there is
higher confidence in thunderstorms at TLH and VLD, otherwise went
with a VCTS for ABY, ECP, and DHN. Outside of thunderstorms VFR
conditions will prevail.
&&
.MARINE...
Southwesterly flow over the waters is forecast to gradually
increase into the weekend as a frontal boundary approaches from
the north, and the Bermuda high strengthens over the western
Atlantic. This may lead to cautionary conditions by Saturday
afternoon, with brief Advisory level conditions Saturday night
into Sunday morning. Thereafter, moderate southwesterly winds are
forecast to continue into early next week.
&&
.FIRE WEATHER...
Average to above average summertime moisture levels will keep Red
Flag conditions out of the forecast for the foreseeable future.
Above average rain chances are expected through the weekend.
&&
.HYDROLOGY...
As upper level troughing digs into the SErn U.S., we will enter a
wet pattern. Expect a rainy weekend with around 2-2.5" of rainfall
across the forecast area with locally higher amounts where showers
are heaviest. While this is over a more widespread area than we`ve
been seeing lately, it is over the course of a 3 day period, and
there are currently no area rivers that are in flood or action
stage. No area rivers are anticipated to reach flood stage at this
time. Some storms with locally higher rainfall amounts may cause
flooding of urban and/or low-lying areas.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 74 94 75 89 72 / 60 50 40 70 50
Panama City 78 91 79 87 77 / 70 50 40 60 50
Dothan 75 95 75 90 73 / 60 50 50 70 50
Albany 75 95 75 91 72 / 70 50 50 70 50
Valdosta 73 93 75 89 72 / 50 50 40 70 50
Cross City 73 91 74 89 73 / 40 40 30 60 40
Apalachicola 77 90 79 87 77 / 60 50 40 60 50
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM...WALSH/WOOL
SHORT TERM/LONG TERM/MARINE...CAMP
AVIATION...NAVARRO/HARRIGAN
HYDROLOGY...MOORE
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
1110 AM EDT Wed Jun 26 2013
.NEAR TERM [Rest of Today]...
No significant changes were made to the inherited forecast which
seems to be generally on track. Isolated to scattered afternoon
thunderstorms are expected today, with somewhat lower coverage than
what we saw yesterday. The best coverage of thunderstorms should be
in the eastern portions of our forecast area - from south-central
Georgia into the Florida Big Bend. The PoP gradient was sharpened a
bit - nudged to ~50% in the Suwannee River vicinity and lowered to
~20% in parts of southeast Alabama. High temperatures remain mostly
unchanged in the mid-90s away from the coasts. We can`t rule out a
stronger storm or two, as is typical this time of year along the
Gulf coast (our climatological probability is ~2% chance of damaging
winds within 25 miles of a point for today). However, a slight
drying in the boundary layer over the past 24 hours should yield a
less robust CAPE profile today which points to lower chances of
isolated severe storms than we saw yesterday.
&&
.SHORT TERM [Thursday through Friday]...
Upper level trofing will continue dipping further south over the Ern
CONUS through the period. This will continue to veer the flow from
SWrly flow to Wrly. The flow Thursday will be moderate (<10 kts),
which would mean a regime 4 sea breeze day. Generally these days have
lots of showers and thunderstorms in north Florida near the coast,
but drier air from the west will enter the region and should keep
coverage a little lower. In fact, because of a cold front to our
north on Thursday, our northern counties have a slightly better
chance for rain on Thursday afternoon than our Florida counties do.
Friday, the flow will be stronger (>10 kts), meaning a regime 5
sea breeze day. These days typically see an earlier start and are
active inland, not just along the coast. As the cold front dips
further south Friday, expanded morning type 5 PoPs north and have a
blend of model confidence and sea breeze for the afternoon, giving a
broad area of chances for showers and thunderstorms Friday. Highs
Thursday will be in the mid 90s and lows Thursday night will be in
the mid 70s.
&&
.LONG TERM [Friday Night through Tuesday]...
A highly amplified upper level pattern with a deep trough becoming
firmly established over the eastern CONUS through the period. A
series of impulses are forecast to round the base of the trough
enhancing convection over the Tri-state area. A fairly potent
shortwave is forecast by the GFS to arrive on Saturday. The Bermuda
ridge will build westward early next week with the axis of the
trough retrograding to the Mississippi Valley. This will place the
local region under deep and very moist southwest flow. From all
appearances this will be an active period for convection with at
least climo PoPs (40-50%) each afternoon. Temps will be near
seasonal levels.
&&
.AVIATION...
[Through 12Z Thursday] A somewhat tricky TAF package for the
overnight hours, as the usually very reliable NARRE and HRRR are
generally devoid of any significant restrictions. Some of the
numerical guidance did show some MVFR level cigs or vis, so did fcst
periods of MVFR conditions at ECP and DHN, which were the 2 sites
that had the most measurable rainfall yesterday. As for the daylight
hours, it appears to be fairly convectively quiet for a Type 4 sea
breeze day with the upper level ridge dominating, but did go with 30
and 40 percent PoPs as mentioned above. Left ECP free from
convection at this time, went with prob30 groups at TLH and DHN, and
finally convective tempos at ABY and VLD.
&&
.MARINE...
Winds and waves over coastal waters will begin to pick up a bit this
weekend as a front approaches from our north. Winds will shift to
westerly at around 10-15 kts with waves building to 2-3 feet Friday
into Saturday. By Sunday, winds will be around 15 kts and waves may
reach about 4 feet, but should begin decreasing again by Monday.
Exercise caution conditions are possible on Sunday.
&&
.FIRE WEATHER...
Relative humidity values will stay safely above Red Flag criteria
through the period.
&&
.HYDROLOGY...
With no river sites currently in flood stage or action stage, and
with QPF for the next 3 days from WPC of <1", no flooding on area
rivers is expected in the next few days. Later this weekend and
early into next week, there is some potential for higher rainfall
amounts as a frontal system dips southward into our area, but they
should still be too low to cause widespread flooding. WPC is showing
QPF of 1-1.5" for Saturday through Sunday and 1-1.75" Monday through
Tuesday.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 96 73 94 74 93 / 40 30 30 20 50
Panama City 90 77 91 78 89 / 30 20 30 20 40
Dothan 94 74 95 75 94 / 30 20 30 30 50
Albany 95 74 95 74 93 / 30 20 40 30 40
Valdosta 94 71 94 74 93 / 50 30 30 30 50
Cross City 93 73 93 73 91 / 40 30 30 20 40
Apalachicola 89 75 89 77 88 / 30 20 20 20 40
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM...Lamers
SHORT TERM...Moore
LONG TERM...Barry
AVIATION...Gould
MARINE...Moore
FIRE WEATHER...Gould
HYDROLOGY...Moore
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
301 AM EDT Wed Jun 26 2013
.NEAR TERM [Today]...
Upper level ridging will continue to dominate the SE US for at least
a couple of more days, giving us hot and humid conditions with high
temps in the middle 90s across the interior, until a shortwave trof
becomes reestablished by late in the week and the upcoming weekend.
With the drier deep layer air, cut back on PoPs just a bit from
Tuesday`s forecast, but still believe the Type 4 Sea Breeze pattern
(light to moderate SW Flow between 1000 and 700 mb) will be
respectable enough to produce PoPs in the 30 to 40 percent range,
highest across the NE half of the CWA. As for storm intensity,
generally poor mid and upper level lapse rates combined with
continued warming aloft should preclude any significant strong to
severe storms, but the fairly light steering flow at the lower
levels could result in some locally heavy rainfall in the stronger
storms.
&&
.SHORT TERM [Thursday through Friday]...
Upper level trofing will continue dipping further south over the Ern
CONUS through the period. This will continue to veer the flow from
SWrly flow to Wrly. The flow Thursday will be moderate (<10 kts),
which would mean a regime 4 sea breeze day. Generally these days have
lots of showers and thunderstorms in north Florida near the coast,
but drier air from the west will enter the region and should keep
coverage a little lower. In fact, because of a cold front to our
north on Thursday, our northern counties have a slightly better
chance for rain on Thursday afternoon than our Florida counties do.
Friday, the flow will be stronger (>10 kts), meaning a regime 5
sea breeze day. These days typically see an earlier start and are
active inland, not just along the coast. As the cold front dips
further south Friday, expanded morning type 5 PoPs north and have a
blend of model confidence and sea breeze for the afternoon, giving a
broad area of chances for showers and thunderstorms Friday. Highs
Thursday will be in the mid 90s and lows Thursday night will be in
the mid 70s.
&&
.LONG TERM [Friday Night through Tuesday]...
A highly amplified upper level pattern with a deep trough becoming
firmly established over the eastern CONUS through the period. A
series of impulses are forecast to round the base of the trough
enhancing convection over the Tri-state area. A fairly potent
shortwave is forecast by the GFS to arrive on Saturday. The Bermuda
ridge will build westward early next week with the axis of the
trough retrograding to the Mississippi Valley. This will place the
local region under deep and very moist southwest flow. From all
appearances this will be an active period for convection with at
least climo PoPs (40-50%) each afternoon. Temps will be near
seasonal levels.
&&
.AVIATION...
[Through 12Z Thursday] A somewhat tricky TAF package for the
overnight hours, as the usually very reliable NARRE and HRRR are
generally devoid of any significant restrictions. Some of the
numerical guidance did show some MVFR level cigs or vis, so did fcst
periods of MVFR conditions at ECP and DHN, which were the 2 sites
that had the most measurable rainfall yesterday. As for the daylight
hours, it appears to be fairly convectively quiet for a Type 4 sea
breeze day with the upper level ridge dominating, but did go with 30
and 40 percent PoPs as mentioned above. Left ECP free from
convection at this time, went with prob30 groups at TLH and DHN, and
finally convective tempos at ABY and VLD.
&&
.MARINE...
Winds and waves over coastal waters will begin to pick up a bit this
weekend as a front approaches from our north. Winds will shift to
westerly at around 10-15 kts with waves building to 2-3 feet Friday
into Saturday. By Sunday, winds will be around 15 kts and waves may
reach about 4 feet, but should begin decreasing again by Monday.
Exercise caution conditions are possible on Sunday.
&&
.FIRE WEATHER...
Relative humidity values will stay safely above Red Flag criteria
through the period.
&&
.HYDROLOGY...
With no river sites currently in flood stage or action stage, and
with QPF for the next 3 days from WPC of <1", no flooding on area
rivers is expected in the next few days. Later this weekend and
early into next week, there is some potential for higher rainfall
amounts as a frontal system dips southward into our area, but they
should still be too low to cause widespread flooding. WPC is showing
QPF of 1-1.5" for Saturday through Sunday and 1-1.75" Monday through
Tuesday.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 95 73 94 74 93 / 30 30 30 20 50
Panama City 91 77 91 78 89 / 30 20 30 20 40
Dothan 95 74 95 75 94 / 30 20 30 30 50
Albany 96 74 95 74 93 / 40 20 40 30 40
Valdosta 96 71 94 74 93 / 40 30 30 30 50
Cross City 94 73 93 73 91 / 30 30 30 20 40
Apalachicola 90 75 89 77 88 / 30 20 20 20 40
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
Near Term/Aviation/Fire Weather...Gould
Short Term/Marine/Hydrology...Moore
Long Term...Barry
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
253 PM CDT WED JUN 26 2013
.DISCUSSION...
308 AM CDT
THE LATEST IN A SERIES OF WEAK SHORTWAVES IN QUASI-ZONAL SOUTHERN
STREAM FLOW HAS BEEN SUPPORTING WIDESPREAD CONVECTION AS IT MOVES
TOWARD THE AREA EARLY THIS MORNING. GRADUALLY OVER THE NEXT TWO
DAYS THE LARGE SCALE PATTERN WILL BE AMPLIFYING INTO A BROAD
ANTICYCLONE ACROSS THE WESTERN CONUS AND A DEEPENING LONGWAVE TROUGH
OVER THE EASTERN STATES. THE WARM HUMID CONDITIONS OF RECENT DAYS
WILL BE REPLACED BY COOL HUMID CONDITIONS BY THE WEEKEND...WHICH
THEN WILL PERSIST INTO NEXT WEEK.
FIRST QUESTION CONCERNS PRECIPITATION TRENDS FOR TODAY. AT 08Z THE
EXISTING AREAS OF CONVECTION ACROSS NORTHEAST IOWA INTO NORTHERN
ILLINOIS WERE LOCATED ALONG FAVORABLE GRADIENTS OF MOISTURE
TRANSPORT ON THE LEADING EDGE OF THE LOW LEVEL JET...AND UNDER A
WEAK SHORTWAVE DEPICTED IN THE RAP MODEL AND VWP OBS AT 850 AND 700
MB. THIS ACTIVITY SHOULD BE MOVING ACROSS NORTHEASTERN ILLINOIS
DURING THE PREDAWN HOURS BUT THEN BEGINNING TO WEAKEN AS THE
LLJ VEERS AND ADJUSTS ITS FOCUS MORE TOWARD CENTRAL AND SOUTHERN
ILLINOIS.
IF THIS ACTIVITY DOES DISSIPATE AS EXPECTED TOWARD MORNING...THE
PROSPECTS OF REDEVELOPMENT TODAY ARE SOMEWHAT UNCERTAIN DESPITE
MODEL QPF SOLUTIONS TO THE CONTRARY. LINGERING MORNING SHOWERS AND
THEN SCATTERED TSRA LATER ARE DEFINITELY NOT OUT OF THE QUESTION
LOCALLY BUT THE MORE FAVORABLE AREAS OF MOISTURE ADVECTION AND STEEP
MID LEVEL LAPSE RATES ARE FARTHER SOUTH TOWARD CENTRAL ILLINOIS AND
FARTHER NORTH ALONG THE WI/MN STATE LINE.
DESPITE THE APPROACH OF A SURFACE/850 FRONTAL ZONE...THE UPPER LEVEL
WAVES APPEAR TO BE SOMEWHAT OUT OF SYNC AND MORE
PROGRESSIVE...LEAVING THE LOWER LEVEL FEATURES UNDER AREAS OF RISING
HEIGHTS ALOFT. IN THE 0530Z SPC DAY 1 OUTLOOK THE SLIGHT RISK
EXTENDS NORTHWEST TOWARD MSP AND THEN WELL SOUTH AND EAST THROUGH
THE TENNESSEE AND OHIO VALLEYS. WOULD NOT BE SURPRISED TO SEE THIS
SPLIT IN LATER UPDATES...WITH THE THUMB TO OUR NORTHWEST SEPARATED
FROM THE AREA TO OUR SOUTH. BUT THAT WOULD BE CUTTING IT PRETTY
FINE GIVEN THE OVERALL UNCERTAINTY WITH THIS SITUATION.
LONG STORY SHORT...FOR TODAY THE PLAN WILL BE TO LOWER POPS INTO THE
CHANCE CATEGORY BY AFTERNOON FOR MOST OF THE AREA BUT KEEP IN MIND
THE PWATS APPROACHING TWO INCHES AND THEREFORE MAINTAIN THE FLASH
FLOOD WATCH AND THE MENTION OF TSRA.
AFTER TODAY THE SITUATION BECOMES ONLY SLIGHTLY MORE CLEAR BUT OF
SEEMINGLY LESSER IMPACT.
AMPLIFICATION OF THE LARGE SCALE FLOW WILL BEGIN TO INFLUENCE THE
LOCAL AREA BY TONIGHT INTO THURSDAY AFTER THE SURFACE TROUGH PUSHES
THROUGH THE AREA AND WINDS AT ALL LEVELS TURN TO THE NORTHWEST. LOW
LEVEL WARMTH AND HUMIDITY DO NOT REALLY DEPART UNTIL FRIDAY WHEN THE
EXPANDING EASTERN TROUGH PUSHES THE UPPER JET SOUTH OF THE AREA AND
USHERS IN SLIGHTLY DRIER BUT MILDER AIR.
WITH ONLY MARGINAL LAPSE RATES AND HEIGHTS ALOFT CONTINUING TO
INCREASE...NEITHER THURSDAY NOR FRIDAY LOOK PARTICULARLY FAVORABLE
FOR WIDESPREAD PRECIPITATION. AS MENTIONED IN AN EARLIER
DISCUSSION...IT WOULD NOT TAKE MUCH OF A SHORTWAVE IN THE UPPER FLOW
TO SUPPORT AN AFTERNOON SHOWER...SO WILL CONTINUE TO CARRY SLIGHT
CHANCE POPS ON BOTH DAYS.
BY THE WEEKEND THE CONVECTIVE INSTABILITY APPEARS TO HAVE
DECREASED...BUT THE PRESENCE OF BOTH A SURFACE AND UPPER LEVEL
TROUGH DROPPING SOUTH ACROSS THE AREA WILL STILL SUPPORT LARGE SCALE
LIFT...PRIMARILY TO THE SOUTH ON SUNDAY. PRECIP CHANCES FINALLY
DECREASE BY EARLY NEXT WEEK AS THE SURFACE AND UPPER SUPPORT
DIMINISH...BUT UNSEASONABLY COOL AIR REMAINS IN PLACE WITH CONTINUED
NORTH TO NORTHEASTERLY WINDS.
LENNING
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* UNCERTAINTIES REMAIN WITH PRECISE WIND DIRECTION THIS AFTERNOON
* MVFR VSBY IN BR POSSIBLE LATE TONIGHT/VERY EARLY THURS AM
* CHANCE OF TSRA AGAIN THURS PM
IZZI
//DISCUSSION...UPDATED 20Z...
WIND DIRECTIONS CONTINUE TO BE A CHALLENGE THIS AFTERNOON WITH
SMALL MESOLOW THAT WAS OVER NW IL PERSISTING SURPRISINGING LONG
AND NOW PUSHING INTO NE IL. WINDS HAVE BEEN VEERING AROUND TO A
MORE WESTERLY DIRECTION AND WITH LATEST AMENDMENTS HAVE ADJUSTED
THE FORECAST ACCORDINGLY. DON`T SEE A GOOD REASON FOR WINDS TO
BACK TO MORE SOUTHERLY AND IF ANYTHING GO MORE WESTERLY THIS
AFTERNOON BEFORE DIMINSHING THIS EVENING.
IZZI
UPDATED 18Z...
OVERNIGHT AND MORNING THUNDERSTORMS HAVE FINALLY DIMINISHED
LEAVING A LARGE POOL OF STABLE AIR OVER THE REGION WHICH SHOULD
RESULT IN MINIMAL THREAT ADDITIONAL CONVECTION DEVELOPING THIS
AFTERNOON OR TONIGHT. WINDS HAVE RAPIDLY SWUNG AROUND TO THE S/SSW
AND WITH FURTHER HEATING/MIXING WOULD EXPECT THE SOUTHERLY WINDS
TO CONTINUE THROUGH THE AFTERNOON WITH ONLY A MINIMAL THREAT OF
WINDS BACKING TO EASTERLY DIRECTION AFTER TODAY. WINDS SHOULD GO
LIGHT/VARIABLE TONIGHT AND COULD ACTUALLY SEE SOME PATCY GROUND
FOG DEVELOP LATE TONIGHT...PARTICULARLY IN THE OUTLYING AREAS. AN
UPPER LEVEL DISTURBANCE IS PROGGED TO SWING THROUGH THE REGION
DURING THE AFTERNOON RESULTING IN SCT`D TSRA DEVELOPING...SOME
POSSIBLY STRONG TO SEVERE.
IZZI
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* LOW-MEDIUM CONFIDENCE IN WIND DIRECTION REMAINDER OF THIS
AFTERNOON
* MEDIUM-HIGH CONFIDENCE IN DRY WEATHER THROUGH THURS MORNING
* LOW-MEDIUM CONFIDENCE IN TSRA CHANCES THURS AFTERNOON
* HIGH CONFIDENCE IN OTHER ELEMENTS
IZZI
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR.
FRIDAY THROUGH SATURDAY...PERIODIC CHANCES OF TSRA.
SATURDAY THROUGH MONDAY...PERIODIC CHANCES OF SHRA.
TUESDAY...CHC TSRA.
BMD
&&
.MARINE...
150 AM CDT
ELONGATED SFC LOW PRESSURE TROUGH OVER THE MID-UPPER MISSOURI
VALLEY WILL MOVE SLOWLY EAST TODAY...WITH VARYING MODEL FORECASTS
DEVELOPING A WEAK SURFACE LOW PRESSURE WAVE IN THE VICINITY OF
NORTHERN IL/IND OR SOUTHERN LAKE MICHIGAN BY THIS EVENING. SOUTH
TO SOUTHEAST WINDS SHOULD DIMINISH IN SPEED AS THE GRADIENT
WEAKENS WITH THE APPROACH OF THE TROUGH THIS AFTERNOON...WITH LAKE
BREEZE ESPECIALLY ALONG THE WESTERN SHORE. THUNDERSTORMS WILL BE
POSSIBLE ESPECIALLY OVER THE SOUTHERN HALF OF THE LAKE...WHICH MAY
RESULT IN SOME LOCALLY STRONGER WINDS. WINDS MAY BECOME SOMEWHAT
VARIABLE AT 10 KT OR LESS TONIGHT AS THE SURFACE TROUGH/COLD FRONT
MOVE SLOWLY ACROSS THE LAKE...EVENTUALLY TAKING ON A WEST-
NORTHWEST DIRECTION THURSDAY AS THE TROUGH MOVES OFF TO THE EAST.
SPEEDS SHOULD REMAIN GENERALLY LIGHT HOWEVER...WITH A RELATIVELY
WEAK GRADIENT INTO FRIDAY.
WEAK HIGH PRESSURE RIDGING WILL DEVELOP SOUTHEAST ACROSS THE
NORTHERN AND CENTRAL HIGH PLAINS INTO THE WEEKEND...WHILE THE LOW
PRESSURE WAVE EVENTUALLY DEEPENS EAST OF THE LAKES. THIS WILL
MAINTAIN A PROLONGED PERIOD OF NORTH-NORTHWEST FLOW ACROSS LAKE
MICHIGAN...THOUGH AGAIN WITH SPEEDS GENERALLY 15 KT OR LESS THROUGH
THE PERIOD.
OTHERWISE...IN THE NEAR TERM SOME PATCHY DENSE FOG WILL LINGER
ACROSS THE NORTHERN PART OF THE LAKE THIS MORNING.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ023-ILZ033-ILZ039 UNTIL 7 PM WEDNESDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 7
PM WEDNESDAY.
LM...NONE.
&&
$$
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
1239 PM CDT WED JUN 26 2013
.DISCUSSION...
308 AM CDT
THE LATEST IN A SERIES OF WEAK SHORTWAVES IN QUASI-ZONAL SOUTHERN
STREAM FLOW HAS BEEN SUPPORTING WIDESPREAD CONVECTION AS IT MOVES
TOWARD THE AREA EARLY THIS MORNING. GRADUALLY OVER THE NEXT TWO
DAYS THE LARGE SCALE PATTERN WILL BE AMPLIFYING INTO A BROAD
ANTICYCLONE ACROSS THE WESTERN CONUS AND A DEEPENING LONGWAVE TROUGH
OVER THE EASTERN STATES. THE WARM HUMID CONDITIONS OF RECENT DAYS
WILL BE REPLACED BY COOL HUMID CONDITIONS BY THE WEEKEND...WHICH
THEN WILL PERSIST INTO NEXT WEEK.
FIRST QUESTION CONCERNS PRECIPITATION TRENDS FOR TODAY. AT 08Z THE
EXISTING AREAS OF CONVECTION ACROSS NORTHEAST IOWA INTO NORTHERN
ILLINOIS WERE LOCATED ALONG FAVORABLE GRADIENTS OF MOISTURE
TRANSPORT ON THE LEADING EDGE OF THE LOW LEVEL JET...AND UNDER A
WEAK SHORTWAVE DEPICTED IN THE RAP MODEL AND VWP OBS AT 850 AND 700
MB. THIS ACTIVITY SHOULD BE MOVING ACROSS NORTHEASTERN ILLINOIS
DURING THE PREDAWN HOURS BUT THEN BEGINNING TO WEAKEN AS THE
LLJ VEERS AND ADJUSTS ITS FOCUS MORE TOWARD CENTRAL AND SOUTHERN
ILLINOIS.
IF THIS ACTIVITY DOES DISSIPATE AS EXPECTED TOWARD MORNING...THE
PROSPECTS OF REDEVELOPMENT TODAY ARE SOMEWHAT UNCERTAIN DESPITE
MODEL QPF SOLUTIONS TO THE CONTRARY. LINGERING MORNING SHOWERS AND
THEN SCATTERED TSRA LATER ARE DEFINITELY NOT OUT OF THE QUESTION
LOCALLY BUT THE MORE FAVORABLE AREAS OF MOISTURE ADVECTION AND STEEP
MID LEVEL LAPSE RATES ARE FARTHER SOUTH TOWARD CENTRAL ILLINOIS AND
FARTHER NORTH ALONG THE WI/MN STATE LINE.
DESPITE THE APPROACH OF A SURFACE/850 FRONTAL ZONE...THE UPPER LEVEL
WAVES APPEAR TO BE SOMEWHAT OUT OF SYNC AND MORE
PROGRESSIVE...LEAVING THE LOWER LEVEL FEATURES UNDER AREAS OF RISING
HEIGHTS ALOFT. IN THE 0530Z SPC DAY 1 OUTLOOK THE SLIGHT RISK
EXTENDS NORTHWEST TOWARD MSP AND THEN WELL SOUTH AND EAST THROUGH
THE TENNESSEE AND OHIO VALLEYS. WOULD NOT BE SURPRISED TO SEE THIS
SPLIT IN LATER UPDATES...WITH THE THUMB TO OUR NORTHWEST SEPARATED
FROM THE AREA TO OUR SOUTH. BUT THAT WOULD BE CUTTING IT PRETTY
FINE GIVEN THE OVERALL UNCERTAINTY WITH THIS SITUATION.
LONG STORY SHORT...FOR TODAY THE PLAN WILL BE TO LOWER POPS INTO THE
CHANCE CATEGORY BY AFTERNOON FOR MOST OF THE AREA BUT KEEP IN MIND
THE PWATS APPROACHING TWO INCHES AND THEREFORE MAINTAIN THE FLASH
FLOOD WATCH AND THE MENTION OF TSRA.
AFTER TODAY THE SITUATION BECOMES ONLY SLIGHTLY MORE CLEAR BUT OF
SEEMINGLY LESSER IMPACT.
AMPLIFICATION OF THE LARGE SCALE FLOW WILL BEGIN TO INFLUENCE THE
LOCAL AREA BY TONIGHT INTO THURSDAY AFTER THE SURFACE TROUGH PUSHES
THROUGH THE AREA AND WINDS AT ALL LEVELS TURN TO THE NORTHWEST. LOW
LEVEL WARMTH AND HUMIDITY DO NOT REALLY DEPART UNTIL FRIDAY WHEN THE
EXPANDING EASTERN TROUGH PUSHES THE UPPER JET SOUTH OF THE AREA AND
USHERS IN SLIGHTLY DRIER BUT MILDER AIR.
WITH ONLY MARGINAL LAPSE RATES AND HEIGHTS ALOFT CONTINUING TO
INCREASE...NEITHER THURSDAY NOR FRIDAY LOOK PARTICULARLY FAVORABLE
FOR WIDESPREAD PRECIPITATION. AS MENTIONED IN AN EARLIER
DISCUSSION...IT WOULD NOT TAKE MUCH OF A SHORTWAVE IN THE UPPER FLOW
TO SUPPORT AN AFTERNOON SHOWER...SO WILL CONTINUE TO CARRY SLIGHT
CHANCE POPS ON BOTH DAYS.
BY THE WEEKEND THE CONVECTIVE INSTABILITY APPEARS TO HAVE
DECREASED...BUT THE PRESENCE OF BOTH A SURFACE AND UPPER LEVEL
TROUGH DROPPING SOUTH ACROSS THE AREA WILL STILL SUPPORT LARGE SCALE
LIFT...PRIMARILY TO THE SOUTH ON SUNDAY. PRECIP CHANCES FINALLY
DECREASE BY EARLY NEXT WEEK AS THE SURFACE AND UPPER SUPPORT
DIMINISH...BUT UNSEASONABLY COOL AIR REMAINS IN PLACE WITH CONTINUED
NORTH TO NORTHEASTERLY WINDS.
LENNING
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* SOME UNCERTAINTIES REMAIN WITH WIND DIRECTION THIS AFTERNOON
* MVFR VSBY IN BR POSSIBLE LATE TONIGHT/VERY EARLY THURS AM
* CHANCE OF TSRA AGAIN THURS PM
IZZI
//DISCUSSION...UPDATED 18Z...
OVERNIGHT AND MORNING THUNDERSTORMS HAVE FINALLY DIMINISHED
LEAVING A LARGE POOL OF STABLE AIR OVER THE REGION WHICH SHOULD
RESULT IN MINIMAL THREAT ADDITIONAL CONVECTION DEVELOPING THIS
AFTERNOON OR TONIGHT. WINDS HAVE RAPIDLY SWUNG AROUND TO THE S/SSW
AND WITH FURTHER HEATING/MIXING WOULD EXPECT THE SOUTHERLY WINDS
TO CONTINUE THROUGH THE AFTERNOON WITH ONLY A MINIMAL THREAT OF
WINDS BACKING TO EASTERLY DIRECTION AFTER TODAY. WINDS SHOULD GO
LIGHT/VARIABLE TONIGHT AND COULD ACTUALLY SEE SOME PATCY GROUND
FOG DEVELOP LATE TONIGHT...PARTICULARLY IN THE OUTLYING AREAS. AN
UPPER LEVEL DISTURBANCE IS PROGGED TO SWING THROUGH THE REGION
DURING THE AFTERNOON RESULTING IN SCT`D TSRA DEVELOPING...SOME
POSSIBLY STRONG TO SEVERE.
IZZI
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* LOW-MEDIUM CONFIDENCE IN WIND DIRECTION THIS AFTERNOON
* MEDIUM-HIGH CONFIDENCE IN DRY WEATHER THROUGH THURS MORNING
* LOW-MEDIUM CONFIDENCE IN TSRA CHANCES THURS AFTERNOON
* HIGH CONFIDENCE IN OTHER ELEMENTS
IZZI
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR.
FRIDAY THROUGH SATURDAY...PERIODIC CHANCES OF TSRA.
SATURDAY THROUGH MONDAY...PERIODIC CHANCES OF SHRA.
TUESDAY...CHC TSRA.
BMD
&&
.MARINE...
150 AM CDT
ELONGATED SFC LOW PRESSURE TROUGH OVER THE MID-UPPER MISSOURI
VALLEY WILL MOVE SLOWLY EAST TODAY...WITH VARYING MODEL FORECASTS
DEVELOPING A WEAK SURFACE LOW PRESSURE WAVE IN THE VICINITY OF
NORTHERN IL/IND OR SOUTHERN LAKE MICHIGAN BY THIS EVENING. SOUTH
TO SOUTHEAST WINDS SHOULD DIMINISH IN SPEED AS THE GRADIENT
WEAKENS WITH THE APPROACH OF THE TROUGH THIS AFTERNOON...WITH LAKE
BREEZE ESPECIALLY ALONG THE WESTERN SHORE. THUNDERSTORMS WILL BE
POSSIBLE ESPECIALLY OVER THE SOUTHERN HALF OF THE LAKE...WHICH MAY
RESULT IN SOME LOCALLY STRONGER WINDS. WINDS MAY BECOME SOMEWHAT
VARIABLE AT 10 KT OR LESS TONIGHT AS THE SURFACE TROUGH/COLD FRONT
MOVE SLOWLY ACROSS THE LAKE...EVENTUALLY TAKING ON A WEST-
NORTHWEST DIRECTION THURSDAY AS THE TROUGH MOVES OFF TO THE EAST.
SPEEDS SHOULD REMAIN GENERALLY LIGHT HOWEVER...WITH A RELATIVELY
WEAK GRADIENT INTO FRIDAY.
WEAK HIGH PRESSURE RIDGING WILL DEVELOP SOUTHEAST ACROSS THE
NORTHERN AND CENTRAL HIGH PLAINS INTO THE WEEKEND...WHILE THE LOW
PRESSURE WAVE EVENTUALLY DEEPENS EAST OF THE LAKES. THIS WILL
MAINTAIN A PROLONGED PERIOD OF NORTH-NORTHWEST FLOW ACROSS LAKE
MICHIGAN...THOUGH AGAIN WITH SPEEDS GENERALLY 15 KT OR LESS THROUGH
THE PERIOD.
OTHERWISE...IN THE NEAR TERM SOME PATCHY DENSE FOG WILL LINGER
ACROSS THE NORTHERN PART OF THE LAKE THIS MORNING.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ023-ILZ033-ILZ039 UNTIL 7 PM WEDNESDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 7
PM WEDNESDAY.
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
1124 AM CDT WED JUN 26 2013
.DISCUSSION...
308 AM CDT
THE LATEST IN A SERIES OF WEAK SHORTWAVES IN QUASI-ZONAL SOUTHERN
STREAM FLOW HAS BEEN SUPPORTING WIDESPREAD CONVECTION AS IT MOVES
TOWARD THE AREA EARLY THIS MORNING. GRADUALLY OVER THE NEXT TWO
DAYS THE LARGE SCALE PATTERN WILL BE AMPLIFYING INTO A BROAD
ANTICYCLONE ACROSS THE WESTERN CONUS AND A DEEPENING LONGWAVE TROUGH
OVER THE EASTERN STATES. THE WARM HUMID CONDITIONS OF RECENT DAYS
WILL BE REPLACED BY COOL HUMID CONDITIONS BY THE WEEKEND...WHICH
THEN WILL PERSIST INTO NEXT WEEK.
FIRST QUESTION CONCERNS PRECIPITATION TRENDS FOR TODAY. AT 08Z THE
EXISTING AREAS OF CONVECTION ACROSS NORTHEAST IOWA INTO NORTHERN
ILLINOIS WERE LOCATED ALONG FAVORABLE GRADIENTS OF MOISTURE
TRANSPORT ON THE LEADING EDGE OF THE LOW LEVEL JET...AND UNDER A
WEAK SHORTWAVE DEPICTED IN THE RAP MODEL AND VWP OBS AT 850 AND 700
MB. THIS ACTIVITY SHOULD BE MOVING ACROSS NORTHEASTERN ILLINOIS
DURING THE PREDAWN HOURS BUT THEN BEGINNING TO WEAKEN AS THE
LLJ VEERS AND ADJUSTS ITS FOCUS MORE TOWARD CENTRAL AND SOUTHERN
ILLINOIS.
IF THIS ACTIVITY DOES DISSIPATE AS EXPECTED TOWARD MORNING...THE
PROSPECTS OF REDEVELOPMENT TODAY ARE SOMEWHAT UNCERTAIN DESPITE
MODEL QPF SOLUTIONS TO THE CONTRARY. LINGERING MORNING SHOWERS AND
THEN SCATTERED TSRA LATER ARE DEFINITELY NOT OUT OF THE QUESTION
LOCALLY BUT THE MORE FAVORABLE AREAS OF MOISTURE ADVECTION AND STEEP
MID LEVEL LAPSE RATES ARE FARTHER SOUTH TOWARD CENTRAL ILLINOIS AND
FARTHER NORTH ALONG THE WI/MN STATE LINE.
DESPITE THE APPROACH OF A SURFACE/850 FRONTAL ZONE...THE UPPER LEVEL
WAVES APPEAR TO BE SOMEWHAT OUT OF SYNC AND MORE
PROGRESSIVE...LEAVING THE LOWER LEVEL FEATURES UNDER AREAS OF RISING
HEIGHTS ALOFT. IN THE 0530Z SPC DAY 1 OUTLOOK THE SLIGHT RISK
EXTENDS NORTHWEST TOWARD MSP AND THEN WELL SOUTH AND EAST THROUGH
THE TENNESSEE AND OHIO VALLEYS. WOULD NOT BE SURPRISED TO SEE THIS
SPLIT IN LATER UPDATES...WITH THE THUMB TO OUR NORTHWEST SEPARATED
FROM THE AREA TO OUR SOUTH. BUT THAT WOULD BE CUTTING IT PRETTY
FINE GIVEN THE OVERALL UNCERTAINTY WITH THIS SITUATION.
LONG STORY SHORT...FOR TODAY THE PLAN WILL BE TO LOWER POPS INTO THE
CHANCE CATEGORY BY AFTERNOON FOR MOST OF THE AREA BUT KEEP IN MIND
THE PWATS APPROACHING TWO INCHES AND THEREFORE MAINTAIN THE FLASH
FLOOD WATCH AND THE MENTION OF TSRA.
AFTER TODAY THE SITUATION BECOMES ONLY SLIGHTLY MORE CLEAR BUT OF
SEEMINGLY LESSER IMPACT.
AMPLIFICATION OF THE LARGE SCALE FLOW WILL BEGIN TO INFLUENCE THE
LOCAL AREA BY TONIGHT INTO THURSDAY AFTER THE SURFACE TROUGH PUSHES
THROUGH THE AREA AND WINDS AT ALL LEVELS TURN TO THE NORTHWEST. LOW
LEVEL WARMTH AND HUMIDITY DO NOT REALLY DEPART UNTIL FRIDAY WHEN THE
EXPANDING EASTERN TROUGH PUSHES THE UPPER JET SOUTH OF THE AREA AND
USHERS IN SLIGHTLY DRIER BUT MILDER AIR.
WITH ONLY MARGINAL LAPSE RATES AND HEIGHTS ALOFT CONTINUING TO
INCREASE...NEITHER THURSDAY NOR FRIDAY LOOK PARTICULARLY FAVORABLE
FOR WIDESPREAD PRECIPITATION. AS MENTIONED IN AN EARLIER
DISCUSSION...IT WOULD NOT TAKE MUCH OF A SHORTWAVE IN THE UPPER FLOW
TO SUPPORT AN AFTERNOON SHOWER...SO WILL CONTINUE TO CARRY SLIGHT
CHANCE POPS ON BOTH DAYS.
BY THE WEEKEND THE CONVECTIVE INSTABILITY APPEARS TO HAVE
DECREASED...BUT THE PRESENCE OF BOTH A SURFACE AND UPPER LEVEL
TROUGH DROPPING SOUTH ACROSS THE AREA WILL STILL SUPPORT LARGE SCALE
LIFT...PRIMARILY TO THE SOUTH ON SUNDAY. PRECIP CHANCES FINALLY
DECREASE BY EARLY NEXT WEEK AS THE SURFACE AND UPPER SUPPORT
DIMINISH...BUT UNSEASONABLY COOL AIR REMAINS IN PLACE WITH CONTINUED
NORTH TO NORTHEASTERLY WINDS.
LENNING
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* SCTD SHRA IN VC OF BUT MOSTLY MISSING ORD/MDW
* SOUTHEAST WINDS WILL TURN MORE SOUTHERLY THIS AFTERNOON
IZZI
//DISCUSSION...UPDATED 14Z...
UPPER LEVEL DISTURBANCE MOVING ACROSS NORTHERN ILLINOIS WILL
CONTINUE TO PRODUCE SCT`D SHOWERS AND THUNDERSTORMS THROUGH THE
REMAINDER OF THE MORNING HOURS. MORE ORGANIZED LINE OF TSRA SW OF
JOT WILL LIFT NE AND LIKELY IMPACT MDW BY AROUND 15Z WITH PERIOD
OF +TSRA AND GUSTY WINDS POSSIBLE. AS DISTURBANCE MOVES SLOWLY
EAST THE COVERAGE OF SHRA/TSRA WILL PROBABLY DECREASE THIS
AFTERNOON. SMALL SFC LOW SW OF RFD LIKELY TO MAINTAIN MOSTLY
EASTERLY COMPONENT TO WINDS THROUGH THE MORNING HOURS WITH LOW
CONFIDENCE ON THE WIND DIRECTION HEADING INTO THE AFTERNOON.
IZZI
UPDATED 12Z...
LINE OF THUNDERSTORMS SPANS FROM NORTH CENTRAL ILLINOIS ESE INTO
NORTHERN INDIANA AND IS FOCUSED ON THE NOSE OF A LOW LEVEL JET.
WHILE THE FOCUS SHOULD GENERALLY LIFT NORTH AND WEAKEN OVER THE NEXT
COUPLE HOURS...THE STORMS HAVE BEEN BACK BUILDING TO THE SOUTH WHICH
HAS KEPT IT OVER OR ON THE DOORSTEP ON ORD...AND MAY CONTINUE TO
PERSIST OVER THE NEXT HOUR OR TWO. WINDS HAVE BECOME MORE
NORTHEAST/EASTERLY UNDER THE INFLUENCE OF CONVECTION...AND CIGS HAVE
DROPPED TO MVFR. AS CONVECTION WANES THIS MORNING...EXPECT SOUTHERLY
WINDS TO RESUME AND FOR MVFR CIGS TO LIFT BACK TO VFR. THERE SHOULD
BE A LULL IN ACTIVITY FROM MID MORNING TO EARLY THIS AFTERNOON FOR
THE CHICAGO TERMINALS. ATTENTION TURNS TO AN APPROACHING MCV MOVING
OVER THE MISSISSIPPI RIVER EARLY THIS MORNING. WHILE THERE IS AN
EXPANSIVE AREA OF STRATIFORM PRECIP AHEAD OF THIS FEATURE...IT
SHOULD DRY/ERODE SOME AS IT PROGRESSES EAST. BECAUSE OF THE CLOUD
COVER AND PERHAPS LIGHT RAIN...IT APPEARS THERE WILL BE LITTLE
OPPORTUNITY FOR THE ATMOSPHERE TO DESTABILIZE TODAY THOUGH THERE
WILL BE SOME PERSISTENT/FESTERING EMBEDDED CONVECTION ASSOCIATED
WITH THE MCV. WINDS APPEAR TO GO LIGHT AND VARIABLE TONIGHT...AND
NAM GUIDANCE AS WELL AS LAV POINT TO FOG/BR AND IFR CIGS DEVELOPING
OVERNIGHT. WILL NOT MENTION YET IN TAFS TO WAIT AND SEE HOW THE REST
OF THE DAY EVOLVES AND IF THERE IS ANY SIGNIFICANT DRYING THIS
AFTERNOON/EVENING.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM-HIGH CONFIDENCE IN SHRA OVER THE REGION THROUGH EARLY
AFTERNOON
* MEDIUM CONFIDENCE IN WINDS THIS AFTERNOON
IZZI
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR.
FRIDAY THROUGH SATURDAY...PERIODIC CHANCES OF TSRA.
SATURDAY THROUGH MONDAY...PERIODIC CHANCES OF SHRA.
TUESDAY...CHC TSRA.
BMD
&&
.MARINE...
150 AM CDT
ELONGATED SFC LOW PRESSURE TROUGH OVER THE MID-UPPER MISSOURI
VALLEY WILL MOVE SLOWLY EAST TODAY...WITH VARYING MODEL FORECASTS
DEVELOPING A WEAK SURFACE LOW PRESSURE WAVE IN THE VICINITY OF
NORTHERN IL/IND OR SOUTHERN LAKE MICHIGAN BY THIS EVENING. SOUTH
TO SOUTHEAST WINDS SHOULD DIMINISH IN SPEED AS THE GRADIENT
WEAKENS WITH THE APPROACH OF THE TROUGH THIS AFTERNOON...WITH LAKE
BREEZE ESPECIALLY ALONG THE WESTERN SHORE. THUNDERSTORMS WILL BE
POSSIBLE ESPECIALLY OVER THE SOUTHERN HALF OF THE LAKE...WHICH MAY
RESULT IN SOME LOCALLY STRONGER WINDS. WINDS MAY BECOME SOMEWHAT
VARIABLE AT 10 KT OR LESS TONIGHT AS THE SURFACE TROUGH/COLD FRONT
MOVE SLOWLY ACROSS THE LAKE...EVENTUALLY TAKING ON A WEST-
NORTHWEST DIRECTION THURSDAY AS THE TROUGH MOVES OFF TO THE EAST.
SPEEDS SHOULD REMAIN GENERALLY LIGHT HOWEVER...WITH A RELATIVELY
WEAK GRADIENT INTO FRIDAY.
WEAK HIGH PRESSURE RIDGING WILL DEVELOP SOUTHEAST ACROSS THE
NORTHERN AND CENTRAL HIGH PLAINS INTO THE WEEKEND...WHILE THE LOW
PRESSURE WAVE EVENTUALLY DEEPENS EAST OF THE LAKES. THIS WILL
MAINTAIN A PROLONGED PERIOD OF NORTH-NORTHWEST FLOW ACROSS LAKE
MICHIGAN...THOUGH AGAIN WITH SPEEDS GENERALLY 15 KT OR LESS THROUGH
THE PERIOD.
OTHERWISE...IN THE NEAR TERM SOME PATCHY DENSE FOG WILL LINGER
ACROSS THE NORTHERN PART OF THE LAKE THIS MORNING.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 7 PM WEDNESDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 7
PM WEDNESDAY.
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
920 AM CDT WED JUN 26 2013
.DISCUSSION...
308 AM CDT
THE LATEST IN A SERIES OF WEAK SHORTWAVES IN QUASI-ZONAL SOUTHERN
STREAM FLOW HAS BEEN SUPPORTING WIDESPREAD CONVECTION AS IT MOVES
TOWARD THE AREA EARLY THIS MORNING. GRADUALLY OVER THE NEXT TWO
DAYS THE LARGE SCALE PATTERN WILL BE AMPLIFYING INTO A BROAD
ANTICYCLONE ACROSS THE WESTERN CONUS AND A DEEPENING LONGWAVE TROUGH
OVER THE EASTERN STATES. THE WARM HUMID CONDITIONS OF RECENT DAYS
WILL BE REPLACED BY COOL HUMID CONDITIONS BY THE WEEKEND...WHICH
THEN WILL PERSIST INTO NEXT WEEK.
FIRST QUESTION CONCERNS PRECIPITATION TRENDS FOR TODAY. AT 08Z THE
EXISTING AREAS OF CONVECTION ACROSS NORTHEAST IOWA INTO NORTHERN
ILLINOIS WERE LOCATED ALONG FAVORABLE GRADIENTS OF MOISTURE
TRANSPORT ON THE LEADING EDGE OF THE LOW LEVEL JET...AND UNDER A
WEAK SHORTWAVE DEPICTED IN THE RAP MODEL AND VWP OBS AT 850 AND 700
MB. THIS ACTIVITY SHOULD BE MOVING ACROSS NORTHEASTERN ILLINOIS
DURING THE PREDAWN HOURS BUT THEN BEGINNING TO WEAKEN AS THE
LLJ VEERS AND ADJUSTS ITS FOCUS MORE TOWARD CENTRAL AND SOUTHERN
ILLINOIS.
IF THIS ACTIVITY DOES DISSIPATE AS EXPECTED TOWARD MORNING...THE
PROSPECTS OF REDEVELOPMENT TODAY ARE SOMEWHAT UNCERTAIN DESPITE
MODEL QPF SOLUTIONS TO THE CONTRARY. LINGERING MORNING SHOWERS AND
THEN SCATTERED TSRA LATER ARE DEFINITELY NOT OUT OF THE QUESTION
LOCALLY BUT THE MORE FAVORABLE AREAS OF MOISTURE ADVECTION AND STEEP
MID LEVEL LAPSE RATES ARE FARTHER SOUTH TOWARD CENTRAL ILLINOIS AND
FARTHER NORTH ALONG THE WI/MN STATE LINE.
DESPITE THE APPROACH OF A SURFACE/850 FRONTAL ZONE...THE UPPER LEVEL
WAVES APPEAR TO BE SOMEWHAT OUT OF SYNC AND MORE
PROGRESSIVE...LEAVING THE LOWER LEVEL FEATURES UNDER AREAS OF RISING
HEIGHTS ALOFT. IN THE 0530Z SPC DAY 1 OUTLOOK THE SLIGHT RISK
EXTENDS NORTHWEST TOWARD MSP AND THEN WELL SOUTH AND EAST THROUGH
THE TENNESSEE AND OHIO VALLEYS. WOULD NOT BE SURPRISED TO SEE THIS
SPLIT IN LATER UPDATES...WITH THE THUMB TO OUR NORTHWEST SEPARATED
FROM THE AREA TO OUR SOUTH. BUT THAT WOULD BE CUTTING IT PRETTY
FINE GIVEN THE OVERALL UNCERTAINTY WITH THIS SITUATION.
LONG STORY SHORT...FOR TODAY THE PLAN WILL BE TO LOWER POPS INTO THE
CHANCE CATEGORY BY AFTERNOON FOR MOST OF THE AREA BUT KEEP IN MIND
THE PWATS APPROACHING TWO INCHES AND THEREFORE MAINTAIN THE FLASH
FLOOD WATCH AND THE MENTION OF TSRA.
AFTER TODAY THE SITUATION BECOMES ONLY SLIGHTLY MORE CLEAR BUT OF
SEEMINGLY LESSER IMPACT.
AMPLIFICATION OF THE LARGE SCALE FLOW WILL BEGIN TO INFLUENCE THE
LOCAL AREA BY TONIGHT INTO THURSDAY AFTER THE SURFACE TROUGH PUSHES
THROUGH THE AREA AND WINDS AT ALL LEVELS TURN TO THE NORTHWEST. LOW
LEVEL WARMTH AND HUMIDITY DO NOT REALLY DEPART UNTIL FRIDAY WHEN THE
EXPANDING EASTERN TROUGH PUSHES THE UPPER JET SOUTH OF THE AREA AND
USHERS IN SLIGHTLY DRIER BUT MILDER AIR.
WITH ONLY MARGINAL LAPSE RATES AND HEIGHTS ALOFT CONTINUING TO
INCREASE...NEITHER THURSDAY NOR FRIDAY LOOK PARTICULARLY FAVORABLE
FOR WIDESPREAD PRECIPITATION. AS MENTIONED IN AN EARLIER
DISCUSSION...IT WOULD NOT TAKE MUCH OF A SHORTWAVE IN THE UPPER FLOW
TO SUPPORT AN AFTERNOON SHOWER...SO WILL CONTINUE TO CARRY SLIGHT
CHANCE POPS ON BOTH DAYS.
BY THE WEEKEND THE CONVECTIVE INSTABILITY APPEARS TO HAVE
DECREASED...BUT THE PRESENCE OF BOTH A SURFACE AND UPPER LEVEL
TROUGH DROPPING SOUTH ACROSS THE AREA WILL STILL SUPPORT LARGE SCALE
LIFT...PRIMARILY TO THE SOUTH ON SUNDAY. PRECIP CHANCES FINALLY
DECREASE BY EARLY NEXT WEEK AS THE SURFACE AND UPPER SUPPORT
DIMINISH...BUT UNSEASONABLY COOL AIR REMAINS IN PLACE WITH CONTINUED
NORTH TO NORTHEASTERLY WINDS.
LENNING
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* SCT`D SHRA & TSRA LIKELY TO PERSIST NEXT FEW HOURS
* EASTERLY COMPONENT TO WINDS EXPECTED NEXT SEVERAL HOURS
* WINDS COULD TRANSITION TO SOUTHERLY OR SOUTHEAST THIS AFTERNOON
IZZI
//DISCUSSION...UPDATED 14Z...
UPPER LEVEL DISTURBANCE MOVING ACROSS NORTHERN ILLINOIS WILL
CONTINUE TO PRODUCE SCT`D SHOWERS AND THUNDERSTORMS THROUGH THE
REMAINDER OF THE MORNING HOURS. MORE ORGANIZED LINE OF TSRA SW OF
JOT WILL LIFT NE AND LIKELY IMPACT MDW BY AROUND 15Z WITH PERIOD
OF +TSRA AND GUSTY WINDS POSSIBLE. AS DISTURBANCE MOVES SLOWLY
EAST THE COVERAGE OF SHRA/TSRA WILL PROBABLY DECREASE THIS
AFTERNOON. SMALL SFC LOW SW OF RFD LIKELY TO MAINTAIN MOSTLY
EASTERLY COMPONENT TO WINDS THROUGH THE MORNING HOURS WITH LOW
CONFIDENCE ON THE WIND DIRECTION HEADING INTO THE AFTERNOON.
IZZI
UPDATED 12Z...
LINE OF THUNDERSTORMS SPANS FROM NORTH CENTRAL ILLINOIS ESE INTO
NORTHERN INDIANA AND IS FOCUSED ON THE NOSE OF A LOW LEVEL JET.
WHILE THE FOCUS SHOULD GENERALLY LIFT NORTH AND WEAKEN OVER THE NEXT
COUPLE HOURS...THE STORMS HAVE BEEN BACK BUILDING TO THE SOUTH WHICH
HAS KEPT IT OVER OR ON THE DOORSTEP ON ORD...AND MAY CONTINUE TO
PERSIST OVER THE NEXT HOUR OR TWO. WINDS HAVE BECOME MORE
NORTHEAST/EASTERLY UNDER THE INFLUENCE OF CONVECTION...AND CIGS HAVE
DROPPED TO MVFR. AS CONVECTION WANES THIS MORNING...EXPECT SOUTHERLY
WINDS TO RESUME AND FOR MVFR CIGS TO LIFT BACK TO VFR. THERE SHOULD
BE A LULL IN ACTIVITY FROM MID MORNING TO EARLY THIS AFTERNOON FOR
THE CHICAGO TERMINALS. ATTENTION TURNS TO AN APPROACHING MCV MOVING
OVER THE MISSISSIPPI RIVER EARLY THIS MORNING. WHILE THERE IS AN
EXPANSIVE AREA OF STRATIFORM PRECIP AHEAD OF THIS FEATURE...IT
SHOULD DRY/ERODE SOME AS IT PROGRESSES EAST. BECAUSE OF THE CLOUD
COVER AND PERHAPS LIGHT RAIN...IT APPEARS THERE WILL BE LITTLE
OPPORTUNITY FOR THE ATMOSPHERE TO DESTABILIZE TODAY THOUGH THERE
WILL BE SOME PERSISTENT/FESTERING EMBEDDED CONVECTION ASSOCIATED
WITH THE MCV. WINDS APPEAR TO GO LIGHT AND VARIABLE TONIGHT...AND
NAM GUIDANCE AS WELL AS LAV POINT TO FOG/BR AND IFR CIGS DEVELOPING
OVERNIGHT. WILL NOT MENTION YET IN TAFS TO WAIT AND SEE HOW THE REST
OF THE DAY EVOLVES AND IF THERE IS ANY SIGNIFICANT DRYING THIS
AFTERNOON/EVENING.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* MEDIUM-HIGH CONFIDENCE IN SHRA/TSRA OVER THE REGION THIS MORNING
* LOW CONFIDENCE IN SHRA/TSRA CHANCES THIS AFTERNOON
* MEDIUM CONFIDENCE IN WIND DIRECTION OUTSIDE OF TSRA THIS MORNING
* LOW CONFIDENCE IN WINDS THIS AFTERNOON
IZZI
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR.
FRIDAY THROUGH SATURDAY...PERIODIC CHANCES OF TSRA.
SATURDAY THROUGH MONDAY...PERIODIC CHANCES OF SHRA.
TUESDAY...CHC TSRA.
BMD
&&
.MARINE...
150 AM CDT
ELONGATED SFC LOW PRESSURE TROUGH OVER THE MID-UPPER MISSOURI
VALLEY WILL MOVE SLOWLY EAST TODAY...WITH VARYING MODEL FORECASTS
DEVELOPING A WEAK SURFACE LOW PRESSURE WAVE IN THE VICINITY OF
NORTHERN IL/IND OR SOUTHERN LAKE MICHIGAN BY THIS EVENING. SOUTH
TO SOUTHEAST WINDS SHOULD DIMINISH IN SPEED AS THE GRADIENT
WEAKENS WITH THE APPROACH OF THE TROUGH THIS AFTERNOON...WITH LAKE
BREEZE ESPECIALLY ALONG THE WESTERN SHORE. THUNDERSTORMS WILL BE
POSSIBLE ESPECIALLY OVER THE SOUTHERN HALF OF THE LAKE...WHICH MAY
RESULT IN SOME LOCALLY STRONGER WINDS. WINDS MAY BECOME SOMEWHAT
VARIABLE AT 10 KT OR LESS TONIGHT AS THE SURFACE TROUGH/COLD FRONT
MOVE SLOWLY ACROSS THE LAKE...EVENTUALLY TAKING ON A WEST-
NORTHWEST DIRECTION THURSDAY AS THE TROUGH MOVES OFF TO THE EAST.
SPEEDS SHOULD REMAIN GENERALLY LIGHT HOWEVER...WITH A RELATIVELY
WEAK GRADIENT INTO FRIDAY.
WEAK HIGH PRESSURE RIDGING WILL DEVELOP SOUTHEAST ACROSS THE
NORTHERN AND CENTRAL HIGH PLAINS INTO THE WEEKEND...WHILE THE LOW
PRESSURE WAVE EVENTUALLY DEEPENS EAST OF THE LAKES. THIS WILL
MAINTAIN A PROLONGED PERIOD OF NORTH-NORTHWEST FLOW ACROSS LAKE
MICHIGAN...THOUGH AGAIN WITH SPEEDS GENERALLY 15 KT OR LESS THROUGH
THE PERIOD.
OTHERWISE...IN THE NEAR TERM SOME PATCHY DENSE FOG WILL LINGER
ACROSS THE NORTHERN PART OF THE LAKE THIS MORNING.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 7 PM WEDNESDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 7
PM WEDNESDAY.
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
629 AM CDT WED JUN 26 2013
.DISCUSSION...
308 AM CDT
THE LATEST IN A SERIES OF WEAK SHORTWAVES IN QUASI-ZONAL SOUTHERN
STREAM FLOW HAS BEEN SUPPORTING WIDESPREAD CONVECTION AS IT MOVES
TOWARD THE AREA EARLY THIS MORNING. GRADUALLY OVER THE NEXT TWO
DAYS THE LARGE SCALE PATTERN WILL BE AMPLIFYING INTO A BROAD
ANTICYCLONE ACROSS THE WESTERN CONUS AND A DEEPENING LONGWAVE TROUGH
OVER THE EASTERN STATES. THE WARM HUMID CONDITIONS OF RECENT DAYS
WILL BE REPLACED BY COOL HUMID CONDITIONS BY THE WEEKEND...WHICH
THEN WILL PERSIST INTO NEXT WEEK.
FIRST QUESTION CONCERNS PRECIPITATION TRENDS FOR TODAY. AT 08Z THE
EXISTING AREAS OF CONVECTION ACROSS NORTHEAST IOWA INTO NORTHERN
ILLINOIS WERE LOCATED ALONG FAVORABLE GRADIENTS OF MOISTURE
TRANSPORT ON THE LEADING EDGE OF THE LOW LEVEL JET...AND UNDER A
WEAK SHORTWAVE DEPICTED IN THE RAP MODEL AND VWP OBS AT 850 AND 700
MB. THIS ACTIVITY SHOULD BE MOVING ACROSS NORTHEASTERN ILLINOIS
DURING THE PREDAWN HOURS BUT THEN BEGINNING TO WEAKEN AS THE
LLJ VEERS AND ADJUSTS ITS FOCUS MORE TOWARD CENTRAL AND SOUTHERN
ILLINOIS.
IF THIS ACTIVITY DOES DISSIPATE AS EXPECTED TOWARD MORNING...THE
PROSPECTS OF REDEVELOPMENT TODAY ARE SOMEWHAT UNCERTAIN DESPITE
MODEL QPF SOLUTIONS TO THE CONTRARY. LINGERING MORNING SHOWERS AND
THEN SCATTERED TSRA LATER ARE DEFINITELY NOT OUT OF THE QUESTION
LOCALLY BUT THE MORE FAVORABLE AREAS OF MOISTURE ADVECTION AND STEEP
MID LEVEL LAPSE RATES ARE FARTHER SOUTH TOWARD CENTRAL ILLINOIS AND
FARTHER NORTH ALONG THE WI/MN STATE LINE.
DESPITE THE APPROACH OF A SURFACE/850 FRONTAL ZONE...THE UPPER LEVEL
WAVES APPEAR TO BE SOMEWHAT OUT OF SYNC AND MORE
PROGRESSIVE...LEAVING THE LOWER LEVEL FEATURES UNDER AREAS OF RISING
HEIGHTS ALOFT. IN THE 0530Z SPC DAY 1 OUTLOOK THE SLIGHT RISK
EXTENDS NORTHWEST TOWARD MSP AND THEN WELL SOUTH AND EAST THROUGH
THE TENNESSEE AND OHIO VALLEYS. WOULD NOT BE SURPRISED TO SEE THIS
SPLIT IN LATER UPDATES...WITH THE THUMB TO OUR NORTHWEST SEPARATED
FROM THE AREA TO OUR SOUTH. BUT THAT WOULD BE CUTTING IT PRETTY
FINE GIVEN THE OVERALL UNCERTAINTY WITH THIS SITUATION.
LONG STORY SHORT...FOR TODAY THE PLAN WILL BE TO LOWER POPS INTO THE
CHANCE CATEGORY BY AFTERNOON FOR MOST OF THE AREA BUT KEEP IN MIND
THE PWATS APPROACHING TWO INCHES AND THEREFORE MAINTAIN THE FLASH
FLOOD WATCH AND THE MENTION OF TSRA.
AFTER TODAY THE SITUATION BECOMES ONLY SLIGHTLY MORE CLEAR BUT OF
SEEMINGLY LESSER IMPACT.
AMPLIFICATION OF THE LARGE SCALE FLOW WILL BEGIN TO INFLUENCE THE
LOCAL AREA BY TONIGHT INTO THURSDAY AFTER THE SURFACE TROUGH PUSHES
THROUGH THE AREA AND WINDS AT ALL LEVELS TURN TO THE NORTHWEST. LOW
LEVEL WARMTH AND HUMIDITY DO NOT REALLY DEPART UNTIL FRIDAY WHEN THE
EXPANDING EASTERN TROUGH PUSHES THE UPPER JET SOUTH OF THE AREA AND
USHERS IN SLIGHTLY DRIER BUT MILDER AIR.
WITH ONLY MARGINAL LAPSE RATES AND HEIGHTS ALOFT CONTINUING TO
INCREASE...NEITHER THURSDAY NOR FRIDAY LOOK PARTICULARLY FAVORABLE
FOR WIDESPREAD PRECIPITATION. AS MENTIONED IN AN EARLIER
DISCUSSION...IT WOULD NOT TAKE MUCH OF A SHORTWAVE IN THE UPPER FLOW
TO SUPPORT AN AFTERNOON SHOWER...SO WILL CONTINUE TO CARRY SLIGHT
CHANCE POPS ON BOTH DAYS.
BY THE WEEKEND THE CONVECTIVE INSTABILITY APPEARS TO HAVE
DECREASED...BUT THE PRESENCE OF BOTH A SURFACE AND UPPER LEVEL
TROUGH DROPPING SOUTH ACROSS THE AREA WILL STILL SUPPORT LARGE SCALE
LIFT...PRIMARILY TO THE SOUTH ON SUNDAY. PRECIP CHANCES FINALLY
DECREASE BY EARLY NEXT WEEK AS THE SURFACE AND UPPER SUPPORT
DIMINISH...BUT UNSEASONABLY COOL AIR REMAINS IN PLACE WITH CONTINUED
NORTH TO NORTHEASTERLY WINDS.
LENNING
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* LINE OT THUNDERSTORMS EARLY THIS MORNING BACK BUILDING
SOUTH...BUT SHOULD EVENTUALLY BEGIN TO LIFT NORTH AWAY FROM AREA
AND WEAKEN.
* ADDITIONAL THUNDERSTORMS POSSIBLE THIS AFTERNOON ASSOCIATED WITH
THE DECAYING SYSTEM MOVING ACROSS THE MISSISSIPPI.
BMD
//DISCUSSION...UPDATED 12Z...
LINE OF THUNDERSTORMS SPANS FROM NORTH CENTRAL ILLINOIS ESE INTO
NORTHERN INDIANA AND IS FOCUSED ON THE NOSE OF A LOW LEVEL JET.
WHILE THE FOCUS SHOULD GENERALLY LIFT NORTH AND WEAKEN OVER THE NEXT
COUPLE HOURS...THE STORMS HAVE BEEN BACK BUILDING TO THE SOUTH WHICH
HAS KEPT IT OVER OR ON THE DOORSTEP ON ORD...AND MAY CONTINUE TO
PERSIST OVER THE NEXT HOUR OR TWO. WINDS HAVE BECOME MORE
NORTHEAST/EASTERLY UNDER THE INFLUENCE OF CONVECTION...AND CIGS HAVE
DROPPED TO MVFR. AS CONVECTION WANES THIS MORNING...EXPECT SOUTHERLY
WINDS TO RESUME AND FOR MVFR CIGS TO LIFT BACK TO VFR. THERE SHOULD
BE A LULL IN ACTIVITY FROM MID MORNING TO EARLY THIS AFTERNOON FOR
THE CHICAGO TERMINALS. ATTENTION TURNS TO AN APPROACHING MCV MOVING
OVER THE MISSISSIPPI RIVER EARLY THIS MORNING. WHILE THERE IS AN
EXPANSIVE AREA OF STRATIFORM PRECIP AHEAD OF THIS FEATURE...IT
SHOULD DRY/ERODE SOME AS IT PROGRESSES EAST. BECAUSE OF THE CLOUD
COVER AND PERHAPS LIGHT RAIN...IT APPEARS THERE WILL BE LITTLE
OPPORTUNITY FOR THE ATMOSPHERE TO DESTABILIZE TODAY THOUGH THERE
WILL BE SOME PERSISTENT/FESTERING EMBEDDED CONVECTION ASSOCIATED
WITH THE MCV. WINDS APPEAR TO GO LIGHT AND VARIABLE TONIGHT...AND
NAM GUIDANCE AS WELL AS LAV POINT TO FOG/BR AND IFR CIGS DEVELOPING
OVERNIGHT. WILL NOT MENTION YET IN TAFS TO WAIT AND SEE HOW THE REST
OF THE DAY EVOLVES AND IF THERE IS ANY SIGNIFICANT DRYING THIS
AFTERNOON/EVENING.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* MEDIUM CONFIDENCE IN A LULL IN PRECIP/TSRA MID MORNING TO EARLY
AFTERNOON.
* LOW CONFIDENCE IN EVOLUTION OF MCV AND RESULTING PRECIP/TSRA
CHANCES THIS AFTERNOON.
* LOW TO MEDIUM CONFIDENCE IN WIND TRENDS.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR.
FRIDAY THROUGH SATURDAY...PERIODIC CHANCES OF TSRA.
SATURDAY THROUGH MONDAY...PERIODIC CHANCES OF SHRA.
TUESDAY...CHC TSRA.
BMD
&&
.MARINE...
150 AM CDT
ELONGATED SFC LOW PRESSURE TROUGH OVER THE MID-UPPER MISSOURI
VALLEY WILL MOVE SLOWLY EAST TODAY...WITH VARYING MODEL FORECASTS
DEVELOPING A WEAK SURFACE LOW PRESSURE WAVE IN THE VICINITY OF
NORTHERN IL/IND OR SOUTHERN LAKE MICHIGAN BY THIS EVENING. SOUTH
TO SOUTHEAST WINDS SHOULD DIMINISH IN SPEED AS THE GRADIENT
WEAKENS WITH THE APPROACH OF THE TROUGH THIS AFTERNOON...WITH LAKE
BREEZE ESPECIALLY ALONG THE WESTERN SHORE. THUNDERSTORMS WILL BE
POSSIBLE ESPECIALLY OVER THE SOUTHERN HALF OF THE LAKE...WHICH MAY
RESULT IN SOME LOCALLY STRONGER WINDS. WINDS MAY BECOME SOMEWHAT
VARIABLE AT 10 KT OR LESS TONIGHT AS THE SURFACE TROUGH/COLD FRONT
MOVE SLOWLY ACROSS THE LAKE...EVENTUALLY TAKING ON A WEST-
NORTHWEST DIRECTION THURSDAY AS THE TROUGH MOVES OFF TO THE EAST.
SPEEDS SHOULD REMAIN GENERALLY LIGHT HOWEVER...WITH A RELATIVELY
WEAK GRADIENT INTO FRIDAY.
WEAK HIGH PRESSURE RIDGING WILL DEVELOP SOUTHEAST ACROSS THE
NORTHERN AND CENTRAL HIGH PLAINS INTO THE WEEKEND...WHILE THE LOW
PRESSURE WAVE EVENTUALLY DEEPENS EAST OF THE LAKES. THIS WILL
MAINTAIN A PROLONGED PERIOD OF NORTH-NORTHWEST FLOW ACROSS LAKE
MICHIGAN...THOUGH AGAIN WITH SPEEDS GENERALLY 15 KT OR LESS THROUGH
THE PERIOD.
OTHERWISE...IN THE NEAR TERM SOME PATCHY DENSE FOG WILL LINGER
ACROSS THE NORTHERN PART OF THE LAKE THIS MORNING.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 7 PM WEDNESDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 7
PM WEDNESDAY.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
313 AM CDT WED JUN 26 2013
.DISCUSSION...
308 AM CDT
THE LATEST IN A SERIES OF WEAK SHORTWAVES IN QUASI-ZONAL SOUTHERN
STREAM FLOW HAS BEEN SUPPORTING WIDESPREAD CONVECTION AS IT MOVES
TOWARD THE AREA EARLY THIS MORNING. GRADUALLY OVER THE NEXT TWO
DAYS THE LARGE SCALE PATTERN WILL BE AMPLIFYING INTO A BROAD
ANTICYCLONE ACROSS THE WESTERN CONUS AND A DEEPENING LONGWAVE TROUGH
OVER THE EASTERN STATES. THE WARM HUMID CONDITIONS OF RECENT DAYS
WILL BE REPLACED BY COOL HUMID CONDITIONS BY THE WEEKEND...WHICH
THEN WILL PERSIST INTO NEXT WEEK.
FIRST QUESTION CONCERNS PRECIPITATION TRENDS FOR TODAY. AT 08Z THE
EXISTING AREAS OF CONVECTION ACROSS NORTHEAST IOWA INTO NORTHERN
ILLINOIS WERE LOCATED ALONG FAVORABLE GRADIENTS OF MOISTURE
TRANSPORT ON THE LEADING EDGE OF THE LOW LEVEL JET...AND UNDER A
WEAK SHORTWAVE DEPICTED IN THE RAP MODEL AND VWP OBS AT 850 AND 700
MB. THIS ACTIVITY SHOULD BE MOVING ACROSS NORTHEASTERN ILLINOIS
DURING THE PREDAWN HOURS BUT THEN BEGINNING TO WEAKEN AS THE
LLJ VEERS AND ADJUSTS ITS FOCUS MORE TOWARD CENTRAL AND SOUTHERN
ILLINOIS.
IF THIS ACTIVITY DOES DISSIPATE AS EXPECTED TOWARD MORNING...THE
PROSPECTS OF REDEVELOPMENT TODAY ARE SOMEWHAT UNCERTAIN DESPITE
MODEL QPF SOLUTIONS TO THE CONTRARY. LINGERING MORNING SHOWERS AND
THEN SCATTERED TSRA LATER ARE DEFINITELY NOT OUT OF THE QUESTION
LOCALLY BUT THE MORE FAVORABLE AREAS OF MOISTURE ADVECTION AND STEEP
MID LEVEL LAPSE RATES ARE FARTHER SOUTH TOWARD CENTRAL ILLINOIS AND
FARTHER NORTH ALONG THE WI/MN STATE LINE.
DESPITE THE APPROACH OF A SURFACE/850 FRONTAL ZONE...THE UPPER LEVEL
WAVES APPEAR TO BE SOMEWHAT OUT OF SYNC AND MORE
PROGRESSIVE...LEAVING THE LOWER LEVEL FEATURES UNDER AREAS OF RISING
HEIGHTS ALOFT. IN THE 0530Z SPC DAY 1 OUTLOOK THE SLIGHT RISK
EXTENDS NORTHWEST TOWARD MSP AND THEN WELL SOUTH AND EAST THROUGH
THE TENNESSEE AND OHIO VALLEYS. WOULD NOT BE SURPRISED TO SEE THIS
SPLIT IN LATER UPDATES...WITH THE THUMB TO OUR NORTHWEST SEPARATED
FROM THE AREA TO OUR SOUTH. BUT THAT WOULD BE CUTTING IT PRETTY
FINE GIVEN THE OVERALL UNCERTAINTY WITH THIS SITUATION.
LONG STORY SHORT...FOR TODAY THE PLAN WILL BE TO LOWER POPS INTO THE
CHANCE CATEGORY BY AFTERNOON FOR MOST OF THE AREA BUT KEEP IN MIND
THE PWATS APPROACHING TWO INCHES AND THEREFORE MAINTAIN THE FLASH
FLOOD WATCH AND THE MENTION OF TSRA.
AFTER TODAY THE SITUATION BECOMES ONLY SLIGHTLY MORE CLEAR BUT OF
SEEMINGLY LESSER IMPACT.
AMPLIFICATION OF THE LARGE SCALE FLOW WILL BEGIN TO INFLUENCE THE
LOCAL AREA BY TONIGHT INTO THURSDAY AFTER THE SURFACE TROUGH PUSHES
THROUGH THE AREA AND WINDS AT ALL LEVELS TURN TO THE NORTHWEST. LOW
LEVEL WARMTH AND HUMIDITY DO NOT REALLY DEPART UNTIL FRIDAY WHEN THE
EXPANDING EASTERN TROUGH PUSHES THE UPPER JET SOUTH OF THE AREA AND
USHERS IN SLIGHTLY DRIER BUT MILDER AIR.
WITH ONLY MARGINAL LAPSE RATES AND HEIGHTS ALOFT CONTINUING TO
INCREASE...NEITHER THURSDAY NOR FRIDAY LOOK PARTICULARLY FAVORABLE
FOR WIDESPREAD PRECIPITATION. AS MENTIONED IN AN EARLIER
DISCUSSION...IT WOULD NOT TAKE MUCH OF A SHORTWAVE IN THE UPPER FLOW
TO SUPPORT AN AFTERNOON SHOWER...SO WILL CONTINUE TO CARRY SLIGHT
CHANCE POPS ON BOTH DAYS.
BY THE WEEKEND THE CONVECTIVE INSTABILITY APPEARS TO HAVE
DECREASED...BUT THE PRESENCE OF BOTH A SURFACE AND UPPER LEVEL
TROUGH DROPPING SOUTH ACROSS THE AREA WILL STILL SUPPORT LARGE SCALE
LIFT...PRIMARILY TO THE SOUTH ON SUNDAY. PRECIP CHANCES FINALLY
DECREASE BY EARLY NEXT WEEK AS THE SURFACE AND UPPER SUPPORT
DIMINISH...BUT UNSEASONABLY COOL AIR REMAINS IN PLACE WITH CONTINUED
NORTH TO NORTHEASTERLY WINDS.
LENNING
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* TSRA LATE TONIGHT/EARLY WEDNESDAY MORNING.
* HEAVY RAIN AND MVFR VSBY LIKELY WITH THE TSRA.
* ADDITIONAL ROUND OF TSRA PSBL WEDNESDAY AFTERNOON.
* LAKE BREEZE PSBL WEDNESDAY AFTERNOON WITH WINDS BCMG E.
JEE
//DISCUSSION...UPDATED 06Z...
HIGH PRESSURE OVER THE SE US REMAINS IN PLACE WHILE A LOW OVER THE
NORTHEASTERN PLAINS SLIDES THROUGH THE WESTERN GREAT LAKES LATER
TODAY. CONVECTION IS CURRENTLY ON THE RADAR IN NORTHEAST IA AND
EAST CENTRAL IL/SOUTHERN IN. THE CONVECTION TO THE SOUTH SHOULD
REMAIN SOUTH OF THE TERMINALS. THE STORMS OVER IA ON THE OTHER
HAND SHOULD CONTINUE EASTWARD BEFORE BEGINNING TO MOVE TOWARD THE
SOUTHEAST. SCATTERED CONVECTION HAS ALSO BLOSSOMED AT THE NOSE OF
THE LOW LEVEL JET IN NORTHWEST IL AND SHOULD CONTINUE TO SEE MORE
SCATTERED CONVECTION. LASTLY...HAVE SEEN A FEW CELLS PULSE UP AND
THEN PULSE DOWN ARND DPA SO MOVED THE TEMPO FOR THUNDER UP BY AN
HOUR AT DPA.
AS FAR AS THE TAFS ARE CONCERNED...FEELING MUCH MORE CONFIDENT IN
TS IMPACTING THE TERMINALS BEFORE SUNRISE. KEPT A 2 HOUR WINDOW IN
THE TAFS SINCE STILL NOT HIGHLY CONFIDENT IN WHEN THE TS WILL MAKE
IT TO THE TERMINALS. ALSO KEPT A PERIOD OF RAIN BEHIND THE
THUNDERSTORMS AS THE IA CONVECTION SHOULD CONSOLIDATE AND HAVE A
REGION OF RAIN SHOWERS BEHIND IT. ODDS ARE THE RAIN WILL END
SOONER THAN INDICATED IN THE TAFS.
SOUTH WINDS ARND 10 KT ARE EXPECTED TOMORROW...WITH A LAKE BREEZE
DEVELOPING IN THE AFTN. THINKING THE WIND SHIFT WILL BE SIMILAR TO
YESTERDAY WITH A BRIEF PERIOD OF DUE EAST WINDS AND A MUCH LONGER
PERIOD OF SE WINDS BEHIND THE LAKE BREEZE. THE LAKE BREEZE SHOULD
MAKE IT THROUGH ALL OF THE EASTERN TERMINALS.
THE LOW/TROUGH MOVES THROUGH TOMORROW WITH YET ANOTHER ROUND OF
TSRA EXPECTED. THINKING TS IS PSBL AT RFD ARND 19Z AND THEN
REACHING ORD BY 21Z. THE COMBINED FORCING OF THE TROUGH AND LAKE
BREEZE COULD LEAD TO SOME VERY HEAVY RAINFALL AND MVFR VSBY. STILL
NOT VERY CONFIDENT IN TIMING AND COVERAGE OF TS THIS AFTERNOON SO
LEFT VCTS IN THE TAFS. WINDS WILL TURN NW TO W BEHIND THE TROUGH
AND SKIES WILL BEGIN TO CLEAR OUT LATE IN THE EVENING.
JEE
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM-HIGH CONFIDENCE IN TSRA TONIGHT...MEDIUM CONFIDENCE WITH
TIMING.
* MEDIUM-LOW CONFIDENCE IN HOW MUCH AND HOW LONG RAIN WILL PERSIST
BEHIND THE THUNDERSTORMS.
* MEDIUM CONFIDENCE IN COVERAGE AND TIMING OF TSRA WEDNESDAY
AFTERNOON.
* MEDIUM CONFIDENCE IN TIMING OF LAKE BREEZE AND WINDS MAY BE MORE
SE THAN FORECAST BEHIND THE LAKE BREEZE.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
JEE
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
THURSDAY AND FRIDAY...GENERALLY VFR OUTSIDE OF COUPLE OF BRIEF PERIODS
OF THUNDERSTORMS.
SATURDAY THROUGH MONDAY...GENERALLY VFR. A COUPLE OF BRIEF PERIODS
OF SHOWERS.
ED F
&&
.MARINE...
150 AM CDT
ELONGATED SFC LOW PRESSURE TROUGH OVER THE MID-UPPER MISSOURI
VALLEY WILL MOVE SLOWLY EAST TODAY...WITH VARYING MODEL FORECASTS
DEVELOPING A WEAK SURFACE LOW PRESSURE WAVE IN THE VICINITY OF
NORTHERN IL/IND OR SOUTHERN LAKE MICHIGAN BY THIS EVENING. SOUTH
TO SOUTHEAST WINDS SHOULD DIMINISH IN SPEED AS THE GRADIENT
WEAKENS WITH THE APPROACH OF THE TROUGH THIS AFTERNOON...WITH LAKE
BREEZE ESPECIALLY ALONG THE WESTERN SHORE. THUNDERSTORMS WILL BE
POSSIBLE ESPECIALLY OVER THE SOUTHERN HALF OF THE LAKE...WHICH MAY
RESULT IN SOME LOCALLY STRONGER WINDS. WINDS MAY BECOME SOMEWHAT
VARIABLE AT 10 KT OR LESS TONIGHT AS THE SURFACE TROUGH/COLD FRONT
MOVE SLOWLY ACROSS THE LAKE...EVENTUALLY TAKING ON A WEST-
NORTHWEST DIRECTION THURSDAY AS THE TROUGH MOVES OFF TO THE EAST.
SPEEDS SHOULD REMAIN GENERALLY LIGHT HOWEVER...WITH A RELATIVELY
WEAK GRADIENT INTO FRIDAY.
WEAK HIGH PRESSURE RIDGING WILL DEVELOP SOUTHEAST ACROSS THE
NORTHERN AND CENTRAL HIGH PLAINS INTO THE WEEKEND...WHILE THE LOW
PRESSURE WAVE EVENTUALLY DEEPENS EAST OF THE LAKES. THIS WILL
MAINTAIN A PROLONGED PERIOD OF NORTH-NORTHWEST FLOW ACROSS LAKE
MICHIGAN...THOUGH AGAIN WITH SPEEDS GENERALLY 15 KT OR LESS THROUGH
THE PERIOD.
OTHERWISE...IN THE NEAR TERM SOME PATCHY DENSE FOG WILL LINGER
ACROSS THE NORTHERN PART OF THE LAKE THIS MORNING.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 7 PM WEDNESDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 7
PM WEDNESDAY.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
113 AM CDT WED JUN 26 2013
.MESOSCALE DISCUSSION...
MCV MENTIONED IN PREVIOUS UPDATE CONTINUES TO TRACK TO THE EAST-
SOUTHEAST ACROSS THE CWA PER GOES SATELLITE EXTRAPOLATION.
EXPECTATION IS THAT THIS CIRCULATION WILL MOVE OUT OF THE
EAST/SOUTHEAST COUNTIES BY 10 PM CDT. CONVECTION WHICH CONTINUES
TO BUBBLE OVER LAKE MICHIGAN/NORTHWEST INDIANA AND OVER THE SOUTH
END OF THE LAKE WILL LIKELY CONTINUE FOR THE NEXT 1-2 HOURS AS THE
MCV COMPLETES ITS TRANSIT OF THE AREA BEFORE MOVING EAST OF THE
FORECAST AREA. SUBSIDENCE/STABILIZATION IN THE IMMEDIATE WAKE OF
THIS FEATURE WILL LIKELY SUPPRESS NEW DEVELOPMENT ACROSS THE
CENTRAL PART OF THE NRN IL CWA FOR A COUPLE OF HOURS...AND
THEREFORE AFTER COLLABORATION WITH SPC HAVE DECIDED TO REMOVE
LASALLE...KENDALL...GRUNDY AND WILL COUNTIES FROM SEVERE
THUNDERSTORM WATCH 363.
WHILE PREVIOUS CONVECTION HAS STABILIZED LOW LEVELS ACROSS THE
SOUTHERN TIER OF OUR CWA COUNTIES IN 363...INCREASING SOUTHERLY LOW
LEVEL JET AS NOTED IN VWP/S TO OUR WEST/SOUTHWEST HAS RESULTED IN
DEVELOPMENT OF NEW DEEP/STRONG CONVECTION ACROSS WESTERN IL AND
THESE STORMS MAY PERSIST ABOVE COLD POOL AND MAINTAIN A SEVERE
THREAT INTO THE PONTIAC/KANKAKEE AREAS IN ANOTHER 1-2 HOURS.
LOOKING FARTHER WEST...MID-LEVEL SHORT WAVE ACROSS THE MID-MISSOURI
VALLEY WAS NOTED IN GOES VAPOR IMAGERY. LAST VIS IMAGES OF THE
EVENING SHOW ACCAS FIELD OVER WESTERN/CENTRAL IA...WITH 3000-4000
J/KG OF MUCAPE INDICATED PER SPC/RAP MESOANALYSIS. CONVECTION
ALLOWING MODELS INCLUDING WRF-NMM AND HRRR RUNS CONTINUE TO IMPLY
THAT THE IA/WESTERN IL AREA WILL BECOME/REMAIN ACTIVE OVERNIGHT...
WITH ONE OR MORE CLUSTERS OF STORMS POTENTIALLY AFFECTING PARTS OF
THE CWA INTO EARLY WEDNESDAY MORNING. 23Z HRRR RUN SEEMS TO HAVE A
REASONABLE HANDLE ON THIS SCENARIO...WITH ACTIVITY CURRENTLY
DEVELOPING OVER WESTERN/CENTRAL IL PERHAPS AFFECTING OUR SOUTHERN
COUNTIES THROUGH 05-07Z...THEN DEPICTING DEVELOPMENT OVER
CENTRAL/EASTERN IA SPREADING ACROSS NRN IL DURING THE PRE-DAWN HOURS.
HEAVY RAINFALL/SEVERE RISK CONTINUE OVERNIGHT...WITH WARM/MOIST AND
UNSTABLE AIR MASS.
RATZER
&&
.DISCUSSION...
256 PM CDT
SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT...
THE ACTIVE WEATHER EXPECTED OVER THE NEXT 24 TO 30 HOURS...INCLUDING
THE SEVERE WEATHER AND FLASH FLOODING THREAT WILL BE THE FOCUS OF
THE SHORT TERM FORECAST.
DUE TO THE INCREASING THREAT FOR PERIODS OF VERY HEAVY RAINFALL IN
SLOW MOVING STORMS TONIGHT INTO WEDNESDAY...I HAVE EXTENDED THE
FLASH FLOOD WATCH FOR THE ENTIRE AREA AND EXTENDED THROUGH
WEDNESDAY.
REGIONAL SATELLITE WATER VAPOR IMAGERY INDICATES AN UPPER LEVEL
DISTURBANCE CURRENTLY MOVING INTO NORTHWESTERN ILLINOIS. AREA VWP
DATA ACROSS EASTERN IOWA AND SOUTHERN WISCONSIN INDICATE THAT THIS
DISTURBANCE IS ASSOCIATED WITH A MID LEVEL SPEED MAX AROUND 50 KT.
THIS IS RESULTING IN AROUND 40 KT OF 0-6 KM SHEAR...PER SPC
MESO-ANALYSIS. THE AIR MASS AHEAD OF THIS FEATURE...ACROSS NORTHERN
ILLINOIS...HAS BECOME INCREASINGLY UNSTABLE OVER THE PAST FEW
HOURS...WITH SURFACE TEMPERATURES IN THE LOW TO MID 80S AND DEW
POINTS IN THE LOWER 70S...ESPECIALLY TO THE SOUTH OF THE SURFACE
BOUNDARY...CURRENTLY IN PLACE ACROSS FAR NORTHERN ILLINOIS.
MODIFYING THE 12 UTC ILX SOUNDING...THIS RESULTS IN AROUND 3500 J/KG
OF MLCAPE WITH LITTLE TO NO CAPE. NOT SURPRISING...THAT
THUNDERSTORMS ARE BEGINNING TO FIRE ACROSS PORTIONS OF CENTRAL
ILLINOIS AS ASCENT CONTINUES TO OVERSPREAD THIS UNSTABLE
ENVIRONMENT. I EXPECT THIS TREND TO CONTINUE...ESPECIALLY ACROSS
SOUTHERN SECTIONS OF THE AREA...WITH THE POTENTIAL OF AN
ORGANIZING FORWARD PROPAGATING CONVECTIVE COMPLEX WITH STRONG
DAMAGING WINDS BEING THE MAIN THREAT. HOWEVER...THE THREAT FOR
SEVERE HAIL WILL ALSO BE A CONCERN...ESPECIALLY EARLY IN THE EVENT.
THIS ACTIVITY WILL LIKELY CONTINUE INTO THE EARLY EVENING.
ADDITIONAL ROUNDS OF CONVECTION ARE LIKELY AGAIN THIS EVENING AND
OVERNIGHT...WITH THE POTENTIAL FOR SLOW MOVING AND BACK BUILDING
THUNDERSTORMS. THE QUASI-ZONAL FLOW PATTERN ACROSS THE CONUS IS IN
THE PROCESS OF AMPLIFYING...IN RESPONSE TO AN UPPER LOW OVER THE
EASTERN PACIFIC. ULTIMATELY THIS WILL SET THE STAGE FOR A BUILDING
MID/UPPER LEVEL RIDGE ACROSS THE WESTERN CONUS AND FALLING HEIGHTS
ACROSS THE GREAT LAKES REGION. THIS PROCESS SHOULD ALLOW
ANOTHER...STRONGER SHORT WAVE...CURRENTLY NOTED IN THE WATER VAPOR
IMAGERY ACROSS THE PLAINS...TO MOVE ACROSS THE AREA BY WEDNESDAY. A
SOUTHWESTERLY LOW LEVEL JET WILL KICK UP AHEAD OF THIS FEATURE
DURING THE EVENING...AND GUIDANCE CONTINUES TO PLACE THE NOSE OF THIS
LOW LEVEL JET RIGHT ACROSS THE AREA TONIGHT. THIS COULD POTENTIALLY
LEAD TO A DECENT FLASH FLOODING EVENT FOR PORTIONS OF THE AREA
TONIGHT INTO WEDNESDAY...WITH A GOOD POTENTIAL FOR SLOW MOVING AND
BACK BUILDING THUNDERSTORMS. CORFIDI VECTORS ARE PROGGED TO BE 5
KT OR LESS TONIGHT AS THE JET VEERS WEST-SOUTHWESTERLY AND OFFSETS
THE CLOUD BEARING FLOW. CONSIDERING THIS...AND THE FACT THAT FLASH
FLOOD GUIDANCE REMAINS LOW ACROSS THE AREA...I DECIDED TO GO
WITH A FLASH FLOOD WATCH FOR THE ENTIRE AREA.
IT APPEARS THESE STORMS WITH HEAVY RAIN WILL CONTINUE INTO THE EARLY
MORNING HOURS ON WEDNESDAY AND THEN INTENSIFY IN STRENGTH BY THE
AFTERNOON...ESPECIALLY ACROSS MY SOUTHERN AND EASTERN AREAS. THIS
COULD ALSO LEAD TO ADDITIONAL SEVERE STORMS...ESPECIALLY SOUTH. IT
IS POSSIBLY THAT THE MORNING ACTIVITY COULD LIMIT THE SEVERE RISK TO
THE NORTH.
KJB
LONG TERM...THURSDAY THROUGH TUESDAY...
350 PM CDT
AMPLIFICATION OF THE WESTERN CONUS RIDGE AND EASTERN TROUGH WILL
BEGIN TO INFLUENCE THE LOCAL AREA BY LATE WEDNESDAY INTO THURSDAY
AFTER A SURFACE TROUGH PUSHES THROUGH THE AREA AND WINDS AT ALL
LEVELS TURN TO THE NORTHWEST. LOW LEVEL WARMTH AND HUMIDITY DO NOT
REALLY DEPART UNTIL FRIDAY WHEN THE EXPANDING EASTERN TROUGH PUSHES
THE UPPER JET SOUTH OF THE AREA AND USHERS IN DRIER AND MILDER AIR.
ON BOTH THURSDAY AND FRIDAY IT WOULD NOT TAKE MUCH OF A WRINKLE IN
THE UPPER FLOW TO SUPPORT AN AFTERNOON SHOWER...SO SLIGHT CHANCE
POPS HAVE BEEN MAINTAINED ON BOTH DAYS. BY THE WEEKEND THE
CONVECTIVE INSTABILITY APPEARS TO HAVE DECREASED...BUT THE PRESENCE
OF BOTH A SURFACE AND UPPER LEVEL TROUGH DROPPING SOUTH ACROSS THE
AREA WILL STILL SUPPORT LARGE SCALE LIFT...PRIMARILY TO THE SOUTH ON
SUNDAY. PRECIP CHANCES FINALLY DECREASE BY EARLY NEXT WEEK AS THE
SURFACE AND UPPER SUPPORT DIMINISH...BUT UNSEASONABLY COOL AIR
REMAINS IN PLACE WITH CONTINUED NORTH TO NORTHEASTERLY WINDS.
LENNING
JEE
&&
.HYDROLOGY...
REDEVELOPMENT OF THUNDERSTORMS LATER THIS AFTERNOON INTO TONIGHT
IS LIKELY...WITH PERIODS OF HEAVY RAINFALL EXPECTED TO ACCOMPANY
THESE THUNDERSTORMS. GUIDANCE CONTINUES TO FAVOR PRECIPITABLE
WATER VALUES AROUND 2.00". ANOTHER DECENT MID LEVEL DISTURBANCE
IS EXPECTED TO APPROACH THE AREA TONIGHT AND INTO WEDNESDAY...AND
THIS SYSTEM LOOKS TO INDUCE A SOUTHWESTERLY LOW LEVEL JET...THAT
COULD OFFSET THE FORWARD STORM MOTION...RESULTING IN SLOW MOVING
OR BACK BUILDING THUNDERSTORMS TONIGHT INTO WEDNESDAY. AT THIS
TIME...UNCERTAINTY REMAINS AS TO WHERE EXACTLY THE HEAVIEST RAIN
WILL FALL...BUT GUIDANCE CONTINUES TO HINT AT NORTHERN ILLINOIS
AND NORTHWESTERN INDIANA. THIS WILL HAVE TO BE WATCHED FOR
POSSIBILITY OF A FLASH FLOOD WATCH FOR MOST OF THE AREA AS
RAINFALL AMOUNTS IN EXCESS OF 2 INCHES IS CERTAINLY POSSIBLE
ACROSS PORTIONS OF THE AREA.
KJB/BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* TSRA LATE TONIGHT/EARLY WEDNESDAY MORNING.
* HEAVY RAIN AND MVFR VSBY LIKELY WITH THE TSRA.
* ADDITIONAL ROUND OF TSRA PSBL WEDNESDAY AFTERNOON.
* LAKE BREEZE PSBL WEDNESDAY AFTERNOON WITH WINDS BCMG E.
JEE
//DISCUSSION...UPDATED 06Z...
HIGH PRESSURE OVER THE SE US REMAINS IN PLACE WHILE A LOW OVER THE
NORTHEASTERN PLAINS SLIDES THROUGH THE WESTERN GREAT LAKES LATER
TODAY. CONVECTION IS CURRENTLY ON THE RADAR IN NORTHEAST IA AND
EAST CENTRAL IL/SOUTHERN IN. THE CONVECTION TO THE SOUTH SHOULD
REMAIN SOUTH OF THE TERMINALS. THE STORMS OVER IA ON THE OTHER
HAND SHOULD CONTINUE EASTWARD BEFORE BEGINNING TO MOVE TOWARD THE
SOUTHEAST. SCATTERED CONVECTION HAS ALSO BLOSSOMED AT THE NOSE OF
THE LOW LEVEL JET IN NORTHWEST IL AND SHOULD CONTINUE TO SEE MORE
SCATTERED CONVECTION. LASTLY...HAVE SEEN A FEW CELLS PULSE UP AND
THEN PULSE DOWN ARND DPA SO MOVED THE TEMPO FOR THUNDER UP BY AN
HOUR AT DPA.
AS FAR AS THE TAFS ARE CONCERNED...FEELING MUCH MORE CONFIDENT IN
TS IMPACTING THE TERMINALS BEFORE SUNRISE. KEPT A 2 HOUR WINDOW IN
THE TAFS SINCE STILL NOT HIGHLY CONFIDENT IN WHEN THE TS WILL MAKE
IT TO THE TERMINALS. ALSO KEPT A PERIOD OF RAIN BEHIND THE
THUNDERSTORMS AS THE IA CONVECTION SHOULD CONSOLIDATE AND HAVE A
REGION OF RAIN SHOWERS BEHIND IT. ODDS ARE THE RAIN WILL END
SOONER THAN INDICATED IN THE TAFS.
SOUTH WINDS ARND 10 KT ARE EXPECTED TOMORROW...WITH A LAKE BREEZE
DEVELOPING IN THE AFTN. THINKING THE WIND SHIFT WILL BE SIMILAR TO
YESTERDAY WITH A BRIEF PERIOD OF DUE EAST WINDS AND A MUCH LONGER
PERIOD OF SE WINDS BEHIND THE LAKE BREEZE. THE LAKE BREEZE SHOULD
MAKE IT THROUGH ALL OF THE EASTERN TERMINALS.
THE LOW/TROUGH MOVES THROUGH TOMORROW WITH YET ANOTHER ROUND OF
TSRA EXPECTED. THINKING TS IS PSBL AT RFD ARND 19Z AND THEN
REACHING ORD BY 21Z. THE COMBINED FORCING OF THE TROUGH AND LAKE
BREEZE COULD LEAD TO SOME VERY HEAVY RAINFALL AND MVFR VSBY. STILL
NOT VERY CONFIDENT IN TIMING AND COVERAGE OF TS THIS AFTERNOON SO
LEFT VCTS IN THE TAFS. WINDS WILL TURN NW TO W BEHIND THE TROUGH
AND SKIES WILL BEGIN TO CLEAR OUT LATE IN THE EVENING.
JEE
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM-HIGH CONFIDENCE IN TSRA TONIGHT...MEDIUM CONFIDENCE WITH
TIMING.
* MEDIUM-LOW CONFIDENCE IN HOW MUCH AND HOW LONG RAIN WILL PERSIST
BEHIND THE THUNDERSTORMS.
* MEDIUM CONFIDENCE IN COVERAGE AND TIMING OF TSRA WEDNESDAY
AFTERNOON.
* MEDIUM CONFIDENCE IN TIMING OF LAKE BREEZE AND WINDS MAY BE MORE
SE THAN FORECAST BEHIND THE LAKE BREEZE.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
JEE
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
THURSDAY AND FRIDAY...GENERALLY VFR OUTSIDE OF COUPLE OF BRIEF PERIODS
OF THUNDERSTORMS.
SATURDAY THROUGH MONDAY...GENERALLY VFR. A COUPLE OF BRIEF PERIODS
OF SHOWERS.
ED F
&&
.MARINE...
234 PM CDT
A LARGE RIDGE OF HIGH PRESSURE WILL PERSIST ACROSS THE SOUTHEAST
STATES THROUGH MID WEEK WHILE A TROUGH OF LOW PRESSURE OVER THE
CENTRAL PLAINS SHIFTS INTO THE UPPER MISSOURI VALLEY THIS EVENING
AND THE UPPER MISSISSIPPI VALLEY WEDNESDAY. THIS WILL KEEP
GENERALLY SOUTHERLY WINDS OVER THE LAKE THROUGH WEDNESDAY. THE
TROUGH WILL THEN DRIFT ACROSS LAKE MICHIGAN WEDNESDAY
EVENING...WITH WINDS GRADUALLY SHIFTING TO MORE NORTHERLY. THE
SOUTHERN END OF THE TROUGH WILL CLOSE OFF INTO A CLOSED LOW OVER
THE EASTERN GREAT LAKES THURSDAY AFTERNOON AND TRACK NORTH INTO
SOUTHERN QUEBEC BY FRIDAY NIGHT. A SECONDARY SURGE OF COOLER AIR
WILL PUSH ACROSS THE LAKE INCREASING WINDS TO 15 TO 20 KT.
NORTHERLY WINDS OF 10 TO 15 KT WILL PERSIST OVER THE LAKE THROUGH
THE END OF THE PERIOD.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 7 PM WEDNESDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 7
PM WEDNESDAY.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS LINCOLN IL
1207 AM CDT WED JUN 26 2013
.DISCUSSION...
ISSUED 900 PM CDT TUE JUN 25 2013
THE STORMS HAVE BECOME LESS NUMEROUS IN COVERAGE OVER THE LAST
COUPLE OF HOURS...ALTHOUGH INDIVIDUAL CLUSTERS OF STORMS HAVE
MAINTAINED SOME VIGOROUS UPDRAFTS WITH LARGE AMOUNTS OF MOISTURE
ALOFT AND VERY HEAVY RAINFALL AND SOME HAIL. WITH COOLING OF
SURFACE TEMPS...WE ARE LOSING SURFACE BASED CAPE. HOWEVER...STORMS
APPEAR TO BE SURVIVING BY BECOMING ELEVATED...WITH A CONTINUED
THREAT OF VERY HEAVY RAIN AND SOME HAIL...BUT LOWER CHANCES OF
WIND DAMAGE.
AS FOR THE TRENDS FOR THE REST OF THE NIGHT...WITH EACH SUCCESSIVE
HOUR OF THE HRRR MODEL...IT HAS SLOWED DOWN THE ARRIVAL OF OUR
LATE NIGHT CONVECTIVE COMPLEX FROM IOWA. IT HAS PICKED UP ON THE
RENEWED CONVECTION IN OUR WESTERN COUNTIES AND IT SHOWS THEM
PROGRESSING TO THE NORTHEAST THEN EAST. A LARGER COMPLEX OF STORMS
IS STILL INDICATED TO ARRIVE IN OUR NW COUNTIES FROM THE NORTHWEST
TOWARD 11Z/6AM. WILL KEEP AND EYE ON TIMING BASED ON SATELLITE AND
RADAR TRENDS...BUT FOR NOW WILL ADJUST LIKELY POPS TO LATER
TONIGHT FOR THE NW COUNTIES. WILL ALSO ADJUST THE WED MORNING
LIKELY POPS BACK TO THE NORTHWEST INSTEAD OF JUST SOUTHEAST OF
I-70. WE MAY BE SEEING THE HRRR CONTINUE TO ADJUST THE TIMING OF
THE NEXT COMPLEX UNTIL IT BECOMES OUR MAIN SEVERE WEATHER PRODUCER
DURING THE DAY ON WEDNESDAY.
UPDATED WEATHER INFORMATION IS ALREADY AVAILABLE.
&&
.AVIATION...
ISSUED 1205 AM CDT WED JUN 26 2013
MAIN EMPHASIS IN THIS FORECAST PERIOD CONTINUES TO REVOLVE AROUND
CONVECTION COVERAGE AND AFFECT ON CIGS AND VSBYS.
LATEST SHORT TERM MODELS CONTINUE TO SUGGEST ANOTHER COMPLEX OF
STORMS DEVELOPING ACROSS IOWA THEN TRACKING E/SE INTO CENTRAL
ILLINOIS TOWARD DAWN. WILL CARRY PREDOMINANT THUNDER AFTER 11Z AT
KPIA...THEN AFTER 13Z FURTHER EAST AT KDEC. AFTER A 3-4 HOUR
PERIOD OF CONVECTION WEDNESDAY MORNING...A LULL IN THE ACTIVITY
MAY DEVELOP. DUE TO UNCERTAINTY...WILL CONTINUE TO ONLY MENTION
VCTS FROM MID MORNING THROUGH MID-AFTERNOON WHEN COLD FRONT PUSHES
THROUGH THE AREA AND SHIFTS BETTER STORM CHANCES FURTHER EAST INTO
INDIANA. WINDS WILL BE SOUTHERLY AT LESS THAN 10KT TONIGHT...THEN
WILL BECOME WESTERLY BY WEDNESDAY AFTERNOON WITH SPEEDS AROUND
10 KTS WITH WIND DIR/SPEED QUITE VARIABLE IN AND NEAR TSRA.
SMITH
&&
.PREV DISCUSSION...
ISSUED 300 PM CDT TUE JUN 25 2013
SEVERE STORM CHANCES WILL REMAIN THE FOCUS OVER THE NEXT 2 DAYS.
FLASH FLOODING POTENTIAL TONIGHT IN THE NORTH WILL ALSO BE A
CONCERN. BEYOND THAT...AN AIRMASS CHANGE IS PROJECTED FOR LATE
THIS WEEK AND WEEKEND. HOWEVER...A CUTOFF UPPER LOW LINGERING OVER
THE HEARTLAND WILL KEEP SHOWERS AND EVEN ISOLATED THUNDERSTORMS IN
THE FORECAST THROUGH EARLY NEXT WEEK.
SHORT TERM...TONIGHT THROUGH FRIDAY.
WE DECIDED TO PUT OUR 5 NORTHERN COUNTIES IN A FLASH FLOOD THROUGH
TONIGHT DUE TO PREVIOUS 3-5 INCH RAINS EARLY MONDAY MORNING AND
THE POTENTIAL FOR ADDITIONAL VERY HEAVY RAINFALL RATES UP TO 2
INCHES AN HOUR WITH ANY THUNDERSTORMS THROUGH TONIGHT. PWATS
REMAIN IN THE 1.7-1.9" RANGE...AND PERIODIC STORMS IN AN EAST-WEST
LINE ACROSS N IL IS POSSIBLE.
ADJUSTING OUR 12Z SOUNDING FOR CURRENT CONDITIONS SHOWS ML-CAPE
VALUES APPROACHING 3500 J/KG ACROSS OUR AREA...WITH LITTLE TO NO
CIN. VARIOUS BOUNDARIES ACROSS THE AREA FROM YESTERDAYS CONVECTION
HAVE ALREADY BEGUN TO FIRE BETWEEN 18-19Z. WATER VAPOR PIX CONFIRM
A SHORTWAVE IN THE FLOW ACROSS IOWA PROGRESSING EAST-NE. THAT WAVE
SHOULD HELP RAMP UP THE COVERAGE OF STORMS AND POSSIBLY PUSH US
INTO SEVERE WEATHER MODE. FREEZING LEVEL AT 14.4K FT MEANS HAIL
WILL NEED INTENSE UPDRAFTS TO REACH SEVERE LEVELS /1"+/...BUT WE HAVE
THE CAPE TO ACCOMPLISH THAT WITH THE STRONGEST STORMS. WIND SHEAR
WILL BE GRADUALLY INCREASING AS WE HEAD INTO THIS EVENING...SO
ROTATING SUPERCELLS WILL BE POSSIBLE AS THE EVENT PROGRESSES.
THE LATEST HRRR IS INDICATING TWO PERIODS OF STORMS POSSIBLE. WE
EXPECT A WAVE OF STORMS THIS EVENING THAT MAY BE FOLLOWED BY
ANOTHER BOWING COMPLEX OF STORMS ROLLING INTO OUR AREA FROM IOWA
REACHING KNOX COUNTY AROUND 06Z/1AM. THOSE STORMS MAY BE STILL
AFFECTING OUR COUNTIES SE OF I-70 WED MORNING BEFORE THEY DEPART
INTO INDIANA. WE WENT WITH SOME LIKELY POPS IN THE MORNING TO
ACCOUNT FOR THAT.
THEN A BREAK IN THE ACTION MAY DEVELOP THE REST OF WED MORNING AS
THE ATMOSPHERE RECHARGES FOR THE AFTERNOON WAVE OF STRONG TO
SEVERE STORMS. IT APPEARS THAT A LINE OF STORMS WILL DEVELOP
ACROSS WEST CENTRAL ILLINOIS BY MID AFTERNOON...THEN PROGRESS
EASTWARD. AN INCREASING LLJ IS EXPECTED TO COINCIDE WITH UPPER
LEVEL WINDS VEERING TO THE NORTHWEST. THAT WILL INCREASE SHEAR AND
HELICITY PARAMETERS AND RAMP UP THE THREAT OF ROTATING STORMS AND
POSSIBLY A FEW TORNADOES...MAINLY EAST OF I-55. WE INCREASED POPS
TO LIKELY IN THE EAST WEDNESDAY AFTERNOON TO ACCOUNT FOR THAT
PERIOD OF SEVERE STORMS.
STORMS SHOULD BE WINDING DOWN WED EVENING AS THE COMPLEX MOVES
INTO INDIANA. THURSDAY AND THURSDAY NIGHT SHOULD BE PRIMARILY
DRY...BUT A FEW DAYTIME SHOWERS WILL BE POSSIBLE IN THE EAST AS
THE UPPER WAVE LINGERS ACROSS THE EAST...AND A FEW SHOWERS MAY
REACH OUR SOUTHWESTERN COUNTIES THUR NIGHT AHEAD OF THE NEXT UPPER
LEVEL WAVE. WE KEPT SLIGHT CHANCE POPS EVERYWHERE ON FRIDAY AS
THAT WAVE PROGRESSES ACROSS IL. PRECIP SHOULD BE SPOTTY...AS
COOLER AND LESS HUMID AIR BEGINS TO FLOW INTO THE AREA ON
NORTHWEST WINDS.
LONG TERM...SATURDAY THROUGH TUESDAY.
WE EXPECT TO BE IN AN EXTENDED PERIOD UP UPPER LEVEL TROUGHING AS
A CUT OFF LOW DEVELOPS ACROSS THE WESTERN GREAT LAKES AND
RETROGRADES AND OSCILLATES OVER THE MIDWEST THROUGH EARLY NEXT
WEEK. PERIODS OF SLIGHT CHANCE AND CHANCE POPS WILL PEPPER THE
EXTENDED FORECAST AS A RESULT...DUE TO VARIOUS SHORTWAVE ROTATING
AROUND THE UPPER LOW. RELATIVELY COOL AIR ALOFT WILL ALSO KEEP
LAPSE RATES MODERATELY HIGH...AND FAVORABLE FOR ANY SUNS HEATING
TO CREATE SHOWERS AND ISOLATED STORMS.
TEMPS WILL SETTLE OUT WITH HIGHS IN THE UPPER 70S TO NEAR 80 AND
LOWS IN THE LOWER 60S FOR MUCH OF THE EXTENDED PERIOD.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 7 AM CDT THIS MORNING FOR ILZ027>031.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
337 PM CDT WED JUN 26 2013
.SYNOPSIS...
ISSUED AT 334 PM CDT WED JUN 26 2013
18Z SFC ANALYSIS HAS THE REMNANTS OF A MESO HIGH AT KDBQ AND A MESO
LOW BETWEEN KSQI AND KFEP. AN OUTFLOW BOUNDARY FROM THE MCS RAN FROM
LAKE MICHIGAN THROUGH CENTRAL ILLINOIS AND THEN TO NEAR KMXO. THE
SYNOPTIC COLD FRONT RAN FROM NEAR KMSP...TO KDSM...TO KFNB. AHEAD OF
THE SYNOPTIC FRONT SEVERAL WEAK TROFS/BOUNDARIES WERE ACROSS EASTERN
IOWA AND MISSOURI. DEW POINTS WERE IN THE 70S WITH 60S OVER THE
GREAT LAKES AND BEHIND THE COLD FRONT.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 334 PM CDT WED JUN 26 2013
DIURNAL CONVECTION HAS FIRED ALONG A THETA E GRADIENT IN CENTRAL
IOWA AND ALONG A PRE-FRONTAL TROF. RAP TRENDS BRING THIS FEATURE
INTO THE WESTERN CWFA LATE THIS AFTERNOON BEFORE WEAKENING THE
THETA E GRADIENT. THUS THE NEW STORMS THAT HAVE DEVELOPED JUST WEST
OF THE CWFA ARE EXPECTED TO MOVE INTO THE WESTERN CWFA DURING THE
LATE AFTERNOON HOURS AND THEN SLOWLY DISSIPATE WITH SUNSET.
AHEAD OF THIS CONVECTION...ISOLATED SHOWERS AND STORMS ARE EXPECTED
TO DEVELOP DURING PEAK HEATING THAT WILL ALSO SLOWLY DISSIPATE WITH
SUNSET.
THE SYNOPTIC COLD FRONT WILL MOVE THROUGH THE CWFA TONIGHT DROPPING
DEW POINTS ABOUT 5 TO 7 DEGREES. WINDS ARE EXPECTED TO BE FAIRLY
LIGHT AND GIVEN THE WET GROUND IN SOME AREAS THERE IS A POTENTIAL
FOR SOME FOG DEVELOPMENT AFTER MIDNIGHT. THIS WILL HAVE TO BE
WATCHED TO SEE HOW IT WILL EVOLVE.
QUIET AND DRY CONDITIONS WILL BE SEEN THURSDAY MORNING ACROSS THE
AREA WHILE AN UPPER LOW MOVES INTO THE NORTHERN GREAT LAKES. DAY
TIME HEATING COMBINED WITH SLIGHTLY COOLER AIR ALOFT SHOULD ALLOW
NEW CONVECTION TO DEVELOP DURING THE AFTERNOON. THE LOWER MOISTURE
LEVELS IN THE ATMOSPHERE AND NORTHWEST FLOW SHOULD RESULT IN THE
CONVECTION BEING ISOLATED TO SCATTERED IN NATURE. ..08..
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 334 PM CDT WED JUN 26 2013
THURSDAY NIGHT AND FRIDAY...AS NORTHWESTERLY STEERING FLOW TAKES
OVER WITH UPPER RIDGE RETROGRADE...DIGGING UPPER WAVE INTO THE
NORTHWESTERN GRT LKS WILL CONNECT WITH TROF INTO THE CENTRAL PLAINS
FOR CONTINUED ISOLATED TO WDLY SCTRD SHOWER/STORM THREAT INTO MID
THU EVENING. BUT BEST FORCING AND CONVERGENCE TO REMAIN JUST TO THE
NORTHEAST AND SOUTHWEST OF THE DVN CWA. WILL EXTEND LOW CHC POPS IN
THE FAR EAST AND MAINTAIN ONGOING POPS IN THE SOUTHWESTERN CWA
THROUGH 03Z FRI. AFTER TROF EMBEDDED IN NW STEERING FLOW
PASSES...EXPECT SOME CLEARING AND COOLER CONDITIONS INTO EARLY FRI
MORNING WITH LOWS WELL DOWN INTO THE 60S...POSSIBLY SOME LOWER 60S
NORTH OF I80. LARGE UPPER CYCLONE COMPLEX TO THEN CONTINUE TO SETTLE
ACRS THE HEART OF THE GRT LKS ON FRI. ASSOCIATED VORT SPOKE ALOFT
AND MID LEVEL COOL POOL TO INDUCE DEEP STEEP LAPSE RATES AND A
INSTABILITY SHOWER SET UP ACRS MN INTO WI AND IL. SOME POTENTIAL FOR
THUNDERSTORMS WITH VERTICAL THERMODYNAMIC PROFILES SUPPORTIVE OF
HAIL IF ENHANCED UPDRAFTS CAN MAINTAIN. THIS ACTIVITY MORE LIKELY
FRIDAY AFTERNOON ACRS THE NORTHEASTERN THIRD OF THE DVN CWA AND WILL
ADJUST POPS ACCORDINGLY. DESPITE INCOMING COOLER AIR INFLUX/
ADVECTION...DEEP MIXING PROFILES UP TO H8 MB STILL TO BOOST TEMPS
INTO THE LOW TO MID 80S WHILE SFC DPTS DRY-DOWN MIX INTO THE LOWER
60S TO UPPER 50S...MAYBE LOWER THAN GUIDANCE SUGGESTS INTO THE MID
50S. BREEZY NORTHWEST WINDS AS WELL IN THIS SCENARIO OF 15 TO 20+
MPH. TIGHTENING CYCLONIC FLOW ALOFT MAY KEEP SHOWERS PECULATING WELL
INTO FRI EVENING BEFORE NOCTURNAL PROCESSES TAKE OVER. EVEN WITH
CLOUD DEBRIS...STILL A COOLER NIGHT WITH WIDESPREAD LOWS IN THE LOW
TO MID 60S.
SATURDAY AND SUNDAY...UNSTABLE VERTICAL PROFILES UNDER ONGOING
CYCLONIC FLOW AND ANOTHER INCOMING VORT SPOKE MAY PRODUCE MORE
WIDESPREAD SHOWERS AND A FEW STORMS/FURTHER TO THE WEST/THEN ON
FRIDAY. CANADIAN LLVL RIDGE AXIS DUMPING DOWN TO THE WEST OF THE AREA
ACRS THE PLAINS. FCST SOUNDING SUGGEST ANOTHER DAY OF DEEP MIXING...
BUT CONTINUED LLVL COOL POOL INFLUX AS WELL AS SHOWERS/CLOUDS WILL
HAVE A BETTER SHOT TO KEEP TEMPS IN THE 70S. CLEAR OUT SAT NIGHT AS
LARGE STOUT CANADIAN HIGH TAKES GRIP OF THE UPPER MIDWEST AND COULD
FOSTER WIDESPREAD LOWS WELL DOWN IN THE 50S BY EARLY SUNDAY MORNING.
HIGH PRESSURE TO THEN TO MIGRATE TOWARD THE GRT LKS ON SUNDAY...WHILE
ALOFT DEEP LONG WAVE TROF EXTENDS TO THE GULF ALONG AND EAST OF THE
MS RVR VALLEY. APPEARS LESSENING CHANCE OF SHOWERS SUNDAY AND
BOUNDARY LAYER NORTHEASTERLY FETCH AGAIN TO POSSIBLY KEEP TEMPS IN
THE 70S FOR HIGHS. SUNDAY NIGHT SEASONABLY COOL AND WELL DOWN IN THE
50S ALONG AND NORTH OF I80.
MONDAY THROUGH NEXT WEDNESDAY...LONG RANGE SIGNALS SUGGEST A GENERAL
BLOCKED PATTERN WITH BOOKEND RIDGES ON THE COASTS AND MID CONUS L/W
TROFFINESS PERSISTING THROUGH WED. BUT THEY ALSO SUGGEST IT TO START
TO MODIFY AND BREAK DOWN THE L/W TROF FEATURE AFTER TUE. THUS IN
GENERAL...BELOW NORMAL TEMPS LOOK TO CONTINUE IN THE VCNTY OF THIS
UPPER TROF..AS WELL AS ALMOST A DAILY THREAT OF POP UP SHOWERS AND
A FEW STORMS. BETTER CHANCES OFF THOUGH TO THE SOUTHEAST OF THE DVN
CWA IN VCNTY OF UPPER LOW MON INTO TUE. ..12..
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1225 PM CDT WED JUN 26 2013
DIURNAL CONVECTION HAS DEVELOPED OVER CENTRAL IOWA AHEAD OF THE COLD
FRONT. THIS CONVECTION WILL MOVE INTO EASTERN IOWA AND SLOWLY
DISSIPATE WITH SUNSET. HIGH MOISTURE LEVELS IN THE ATMOSPHERE HAS
RESULTED IN SOME MVFR CIGS TO DEVELOP. IF A TSRA WOULD IMPACT A TAF
SITE A BRIEF PERIOD OF IFR CONDITIONS WILL BE POSSIBLE. AFT SUNSET
VFR CONDITIONS ARE EXPECTED. HOWEVER...THE WET GROUND AND LIGHT
WINDS MAY ALLOW FOG TO DEVELOP AFT 06Z/27. IF THIS OCCURS...THERE IS
A POTENTIAL FOR IFR/LIFR CONDITIONS. ..08..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...08
SHORT TERM...08
LONG TERM...12
AVIATION...08
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1233 PM CDT WED JUN 26 2013
.UPDATE...
ISSUED AT 1225 PM CDT WED JUN 26 2013
THE NOCTURNAL MCS HAS DISSIPATED ACROSS ILLINOIS. BOUNDARIES LEFT
OVER FROM THIS CONVECTION ALLOWED NEW CONVECTION TO DEVELOP THIS
MORNING BEFORE DOWNWARD MOTION FROM THE MCV CAUSED IT TO ALSO
DISSIPATE.
WATER VAPOR SHOWS A RESPECTABLE VORT MAX MOVING FROM MINNESOTA
INTO IOWA. RAP TRENDS INDICATE DOWNWARD MOTION WILL CONTINUE INTO
THE EARLY AFTERNOON BEFORE LIFT FROM THE APPROACHING VORT MAX
INCREASES. THIS LIFT MAY BE ENOUGH WHEN COMBINED WITH THE
APPROACHING COLD FRONT TO ALLOW ISOLATED TO SCATTERED CONVECTION
TO DEVELOP MID TO LATE AFTERNOON. ..08..
UPDATE ISSUED AT 1000 AM CDT WED JUN 26 2013
THE NOCTURNAL MCS THAT PRODUCED THE EXTREMELY HEAVY RAINFALL IS
RAPIDLY DECAYING ACROSS ILLINOIS. COLD POOLS AND OUTFLOW
BOUNDARIES FROM THE MCS IS PROVIDING A FOCUS FOR NEW CONVECTION
ACROSS IOWA.
WATER VAPOR SHOWS A RESPECTABLE VORT MAX DIVING SOUTHEAST INTO
IOWA FROM MINNESOTA WHICH IS HELPING TO DRIVE SOME OF THE
CONVECTION. DOWNWARD MOTION BEHIND THE DECAYING MCS IS HELPING TO
DISSIPATE THE NEW CONVECTION ACROSS IOWA. HOWEVER...RAP TRENDS
SHOW LIFT WILL BE ON THE INCREASE AGAIN BY LATE MORNING AND INTO
THE AFTERNOON. SO...CONVECTION IS EXPECTED TO PERSIST AND MAY
EXPAND SOME IN AREAL COVERAGE DURING THE AFTERNOON. ..08..
&&
.SYNOPSIS...
ISSUED AT 335 AM CDT WED JUN 26 2013
AS OF 08Z LOW PRESSURE WAS FOUND IN WESTERN IOWA...WITH TROUGH
EXTENDING NORTH INTO THE RED RIVER VALLEY AND COLD FRONT TRAILING
OFF TO THE SW INTO KANSAS. TWO DIFFUSE WARM FRONTAL BOUNDARIES
WERE FOUND ALONG NORTHERN PARTS OF CWFA AND JUST TO THE SOUTH. AN
MCV WAS SEEN ON RADAR JUST SW OF DUBUQUE WITH A LINE OF STORMS
EXTENDING SW TO NEAR IOWA CITY. THIS LINE WAS STARTING TO INDICATE
SOME BOWING AGAIN. ADDITIONAL CONVECTIVE ACTIVITY LINGERS TO THE
NW WHERE STORMS HAD EARLY SAT STILL CAUSING SOME FLASH FLOODING IN
BUCHANAN COUNTY AND NORTHERN LINN COUNTY. DEW POINTS ARE MAINLY
IN THE MID 60S TO LOWER 70S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 335 AM CDT WED JUN 26 2013
FOCUS ON SHORT TERM IS IN WALKING OUT THIS EARLY MORNING
CONVECTION. MAINLY TURNING OUT TO BE HEAVY RAIN EVENT...WITH SOME
MARGINALLY SEVERE WIND GUSTS POSSIBLE IN BOWING PHASES AS THE LINE
MOVES ACROSS EAST CENTRAL IOWA AND NW ILLINOIS...GENERALLY ALONG
AND NE OF A LINE FROM WASHINGTON IOWA...TO MACOMB ILLINOIS. EXPECT
ACTIVITY TO DIMINISH THROUGH THE MORNING HOURS AS LOW MOVES ACROSS
THE AREA AND SUBSIDENCE ON NW FLOW WORKS INTO THE AREA BEHIND THE
DEPARTING STORMS.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 335 AM CDT WED JUN 26 2013
NOT MUCH CHANGE TO THE EXTENDED FORECAST WHICH IS RELATIVELY QUIET
FOR A CHANGE...COOLER...AND LESS HUMID. A TROUGH DIGS ACROSS THE
EAST COAST WHILE A RIDGE BUILDS...WITH THE CWFA IN NW FLOW THROUGH
THE PERIOD. WEAK DISTURBANCES WILL MOVE ACROSS THE AREA...WITH
ONLY SLIGHT/LOW END CHANCE POPS ATTM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1225 PM CDT WED JUN 26 2013
VFR WX IS EXPECTED THROUGH 02Z/27. DOWNWARD MOTION BEHIND THE
DISSIPATED TSRA COMPLEX WILL SUPPRESS NEW CONVECTION UNTIL AFT
20Z/26. PROBABILITY OF A TSRA AFFECTING A TAF SITE IS LOW BUT VCTS
WAS INCLUDED IN THE 18Z TAFS. AFT 02Z/27 VFR WX SHOULD CONTINUE.
LIGHT WINDS AND WET GROUND MAY RESULT IN FOG DVLPG AFT 06Z/27. IF
THIS OCCURS...MVFR CONDITIONS WOULD BE SEEN WITH A POTENTIAL FOR
IFR/LIFR CONDITIONS. ..08..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...08
SYNOPSIS...14
SHORT TERM...14
LONG TERM...14
AVIATION...08
AREA FORECAST DISCUSSION
NWS TOPEKA KS
329 AM CDT WED JUN 26 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 305 AM CDT WED JUN 26 2013
0Z UPPER AIR OBSERVATIONS SHOWED A RATHER SHARP MID LEVEL WAVE
OVER THE MISSOURI RIVER WITH A NARROW AXIS OF WARM AIR ADVECTION
AHEAD OF IT AND ELEVATED CONVECTION BLOSSOMED OVERNIGHT IN
NORTHERN MISSOURI. A VERY MODIFIED COLD FRONT WITH THIS WAVE WAS
BISECTING KANSAS FROM SOUTHWEST TO NORTHEAST AT 07Z. NEARBY 0Z
850MB TEMPS WERE 20C AT KTOP...26C BEHIND THE FRONT AT KLBF...AND
31C AND KDDC. RECENT AREA PROFILERS AND RADARS INDICATE MODERATE
WESTERLY FLOW AT THIS LEVEL BRINGING WARMER AIR INTO EASTERN
KANSAS.
MID LEVEL SUBSIDENCE BEHIND THE WAVE AND WEAK LOW LEVEL CONVERGENCE
SHIFTING SOUTHEAST OF EAST CENTRAL KANSAS BY EARLY AFTERNOON SHOULD
KEEP ANY PRECIP IN CHECK FOR TODAY AND TONIGHT. 850MB TEMPS SHOULD
BE A FEW DEGREES WARMER THIS AFTERNOON ESPECIALLY IN EASTERN
LOCATIONS WITH HIGHS SEVERAL DEGREES WARMER THERE IN ORDER COMPARED
TO THE TUESDAY. NORTHERLY LOW LEVEL FLOW BEHIND THE MODIFIED FRONT
SHOULD KEEP AFTERNOON DEWPOINTS IN THE 60S FOR THE MOST PART AND
HEAT INDICES BELOW EXTREME VALUES. LIGHT WINDS AND ONLY SOME CIRRUS
EXPECTED TONIGHT WITH WEAK SURFACE HIGH NEARBY. DROPPED LOWS A FEW
DEGREES WITH THESE FEATURES IN MIND.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 305 AM CDT WED JUN 26 2013
THURSDAY LIKELY TO BRING BOTH THE THE HOTTEST DAY OF THE WEEK TO
THE AREA AS WELL AS THE GREATEST RISK FOR SEVERE WEATHER. 850MB
THERMAL RIDGE NOSES EASTWARD ACROSS THE STATE WITH NEAR 30C AT THE
WESTERN FRINGES OF THE CWA. TEMPERATURES OUT IN THE WESTERN
COUNTIES EXPECTED TO TOP 100 ALONG/WEST OF MANHATTAN WITH UPPER
90S EASTWARD. EVEN WITH MIXING DOWN SOME DRIER DEWPOINTS...HEAT
INDICES STILL RUNNING 104 TO 106 FOR THE ENTIRE AREA. SEVERE
THREAT INCREASES AS A POTENTIAL MCS IS PROGGED TO DEVELOP OVER
NEBRASKA ALONG THE THERMAL GRADIENT ON THE NOSE OF THE LLJ BY
12Z...AND PROPAGATE SOUTHEAST AS THE JET VEERS ALONG THE
BOUNDARY INTO NE KS / WRN MO. SURFACE FRONT ALSO ASSOCIATED WITH
THIS FEATURE MOVES SOUTHWARD THROUGH THE FA DURING PEAK HEATING.
CONCERNS ARE THAT CONSIDERABLE DRY AIR DEEP IN THE BOUNDARY LAYER
COUPLED WITH AVAILABLE INSTABILITY OF 1500-3000K/KG ATOP INVERTED
V SOUNDINGS MAY BRING A SIGNIFICANT WIND THREAT FROM ANY
CONVECTION THAT DEVELOPS OVER EASTERN KS IN THE AFTERNOON AND
EVENING HOURS. WILL MONITOR AS CONDITIONS DEVELOP.
INCOMING HIGH PRESSURE FRIDAY STILL ON THE WARM LEADING EDGE OF
THE HIGH...AND TEMPERATURES STILL EXPECTED TO REACH LOWER 90S IN
ABUNDANT SUNSHINE AND GOOD MIXING. PATTERN THEN SETS UP FOR A COOL
LATE JUNE EARLY JULY PATTERN AS WESTERN RIDGE AMPLIFIES AND ENERGY
ROTATING AROUND THE PERIPHERY INTO THE EASTERN TROF STRENGTHENS
THE AMPLIFICATION IN THE PATTERN...LEAVING PLAINS STATES IN
NORTHERLY FLOW THROUGH THE END OF THE FORECAST PERIOD. AS
COMPARED TO THE FORECAST HOT WEATHER FOR THURSDAY...850MB TEMPS
ARE PROGGED TO BE 14C BY NEXT TUESDAY AFTERNOON...WITH HIGHS
FORECAST IN THE LOWER 80S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1122 PM CDT TUE JUN 25 2013
WITH WATER VAPOR SHOWING AN UPPER LEVEL TROUGH PASSING EAST OF THE
MO RIVER AND THE DIURNALLY DRIVEN CONVECTION IN SOUTH CENTRAL KS
DISSIPATING...THINK VFR CONDITIONS WILL PREVAIL OVERNIGHT. BOTH
THE NAM AND RAP SHOW THE BEST COMBINATION OF ISENTROPIC UPGLIDE
AND SATURATION TO REMAIN OVER NORTHERN MO AND MOVING TO THE EAST
OVERNIGHT. WITH NEW ELEVATED STORMS ALREADY EAST OF THE MO
RIVER...IT IS HARD TO SEE ANYTHING FORMING IN KS. WINDS SHOULD
GRADUALLY DIMINISH OVERNIGHT AS THE SFC LOW CONTINUES TO FILL AND
THE PRESSURE GRADIENT WEAKENS.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...65
LONG TERM...67
AVIATION...WOLTERS
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1122 PM CDT TUE JUN 25 2013
.UPDATE...
ISSUED AT 726 PM CDT TUE JUN 25 2013
HAVE UPDATED THE FORECAST TO TAKE OUT THE SLIGHT CHANCE OF
THUNDERSTORMS FOR THE EARLY EVENING. SURFACE OBS AND LAPS ANALYSIS
SHOWS THE STRONGER LOW LEVEL CONVERGENCE BETWEEN MCPHERSON AND
PRATT ALONG THE SURFACE BOUNDARY. ISOLATED CONVECTION HAS FORMED
IN THIS AXIS OF LOW LEVEL CONVERGENCE. WITH THE LOW LEVEL
MOISTURE FLUX LESS IMPRESSIVE ACROSS NORTH CENTRAL KS AND THE CU
FIELD SHOWING LITTLE VERTICAL DEVELOPMENT OUTSIDE OF THE ENHANCED
CONVERGENCE NEAR HUTCHINSON...THINK ADDITIONAL DEVELOPMENT IS
UNLIKELY AS THE BOUNDARY LAYER STARTS TO STABILIZE WITH THE LOSE
OF DAY TIME HEATING.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 343 PM CDT TUE JUN 25 2013
LATEST WATER VAPOR LOOP SHOWS A WAVE MOVING ACROSS WESTERN KANSAS.
SPEED LOOP OF VISIBLE SATELLITE SHOWS SOME CIRCULATION OVER NORTH
CENTRAL KANSAS WITH A CU FIELD TO ITS EAST AND NORTHEAST. SURFACE
TROUGH FROM A LOW IN SOUTHWEST KANSAS NORTHEAST INTO NEBRASKA.
LATEST MESO ANALYSIS CONTINUES TO SHOW DEEP MOISTURE OVER EASTERN
KANSAS. DEEP MOISTURE CONVERGENCE WAS OCCURRING OVER NORTHEAST AND
NORTH CENTRAL KANSAS AHEAD OF THE ABOVE MENTIONED FEATURE. EML WAS
WORKING ITS WAY ACROSS SOUTH CENTRAL KANSAS THIS AFTERNOON WHERE 15
DEGREE CELSIUS AIR RESIDES.
THE HRRR AND WRF SHOW SOME ISOLATED CONVECTION DEVELOPING NORTH OF
I-70 LATE THIS AFTERNOON AND EVENING IN NORTH CENTRAL AND NORTHEAST
KANSAS. HAVE ONLY ABOUT A 10 TO 15 PERCENT CHANCE OF A THUNDERSTORM
IN THE FORECAST FOR A FEW HOURS THIS EVENING. ATMOSPHERE REMAINS
UNSTABLE WITH LITTLE TO NO CONVECTIVE INHIBITION. 0-6KM SHEAR NEAR
40 KTS SO COULD SEE A SUPERCELL OR TWO DEVELOP. LOW LEVEL JET VEERS
TONIGHT WITH THE DEEPER MOISTURE MOVING OFF TO THE EAST. A COLD
FRONT IN THE WESTERN PLAINS WILL MOVE SOUTHEAST AND ACROSS NORTH
CENTRAL AND NORTHEAST KANSAS LATER TONIGHT THROUGH MID DAY
WEDNESDAY. SURFACE HIGH PRESSURE WILL MOVE IN BEHIND THE FRONT ON
WEDNESDAY. TEMPERATURES WILL BE MILD AGAIN TONIGHT WITH LOWS MAINLY
IN THE 70S. HIGHS ON WEDNESDAY WILL BE IN THE MID 90S IN THE
NORTHEAST CORNER TO NEAR 100 IN NORTH CENTRAL KANSAS. AFTERNOON HEAT
INDICES IN THE 98 TO 104 DEGREE RANGE ARE EXPECTED.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 343 PM CDT TUE JUN 25 2013
THE LLVL FLOW VEERS AROUND TO THE SOUTHEAST THEN SOUTH TO SOUTHWEST
WEDNESDAY NIGHT INTO THURSDAY...WARMER AIR AND DEEPER MOISTURE WILL
ADVECT BACK INTO THE COUNTY WARNING AREA. A STRONG 850MB THERMAL
AXIS WILL PUSH WARMER TEMPS NORTHEAST INTO THE CWA...ESPECIALLY THE
SOUTHWEST COUNTIES WHERE HIGHS IN THE 100-103 RANGE SHOULD BE COMMON
AS MIXING ACROSS THE AREA BY AFTERNOON DEEPENS SUBSTANTIALLY. THIS
WILL NOT ONLY RAISE TEMPS...BUT AT THE SAME TIME...LOWER
DEWPOINTS...MAINLY OVER THE WESTERN COUNTIES. HEAT INDICES THURSDAY
WILL COMMONLY BE IN THE 100-105 RANGE. A SUBSTANTIAL EML WILL BE IN
PLACE TO THE START THE AFTERNOON...BUT BY LATE IN THE DAY OVER THE
NORTHERN COUNTIES...IT WILL LIKELY ERODE WITH ISOLATED THUNDERSTORMS
POSSIBLE AND WILL CARRY A SLIGHT CHANCE POP. ALTHOUGH WINDS ALOFT
WILL NOT BE ESPECIALLY STRONG...AN AREA OF HIGH CAPE VALUES AND
INCREASING DIRECTIONAL SHEAR THROUGH 6KM WILL DEVELOP ALONG AND
AHEAD OF THE BOUNDARY SLIPPING SOUTHWARD LATE IN THE DAY AND
EVENING. WOULD EXPECT SOME INCREASE IN COVERAGE OF ANY LATE
AFTERNOON CONVECTION. ALTHOUGH HAIL IS POSSIBLE...A DEEP LAYER OF
NEARLY ADIABATIC LAPSE RATES COULD MAKE STRONG WINDS GUSTS THE
PRIMARY HAZARD FOR ANY CONVECTION THAT MAY DEVELOPS. MODELS SEEM A
FAIRLY GOOD AGREEMENT THAT ANY CONVECTION THAT DEVELOPS...SHOULD BE
SOUTH OF THE CWA BY SUNRISE FRIDAY AS THE BOUNDARY MOVES SOUTHWARD.
WILL KEEP THE HIGHEST POPS OVER THE FAR NORTHEAST/EASTERN COUNTIES.
IT SHOULD ALSO MARK THE BEGINNING OF A GRADUAL DECLINE IN BOTH
TEMPERATURES AND DEWPOINTS AS A LARGE SCALE UPPER TROUGH DEEPENS
THROUGH THE WEEKEND OVER THE EASTERN CONUS. DEWPOINTS WILL COMMONLY
BE IN THE 50S TO NEAR 60 DEGREES THROUGH THE WEEKEND. ALTHOUGH IT
WILL STILL BE THE LOW TO MIDDLE 90S MOST AREAS FRIDAY...HIGHS IN THE
80S WILL BE THE RULE THROUGH THE WEEKEND INTO EARLY NEXT WEEK. WILL
CARRY A SLIGHT CHANCE FOR THUNDERSTORMS OVER THE FAR NORTHEAST ON
SUNDAY. ALTHOUGH CANNOT TOTALLY RULE OUT ISOLATED CONVECTION IN THE
NORTHWEST FLOW REGIME OVER THE AREA...DRIER AIR OVER THE AREA AND
THE LACK OF ANY CONSISTENT FORCING MECHANISM TO DEVELOP PRECIP
WARRANTS KEEPING THE REMAINDER OF THE FCST DRY AT THIS POINT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1122 PM CDT TUE JUN 25 2013
WITH WATER VAPOR SHOWING AN UPPER LEVEL TROUGH PASSING EAST OF THE
MO RIVER AND THE DIURNALLY DRIVEN CONVECTION IN SOUTH CENTRAL KS
DISSIPATING...THINK VFR CONDITIONS WILL PREVAIL OVERNIGHT. BOTH
THE NAM AND RAP SHOW THE BEST COMBINATION OF ISENTROPIC UPGLIDE
AND SATURATION TO REMAIN OVER NORTHERN MO AND MOVING TO THE EAST
OVERNIGHT. WITH NEW ELEVATED STORMS ALREADY EAST OF THE MO
RIVER...IT IS HARD TO SEE ANYTHING FORMING IN KS. WINDS SHOULD
GRADUALLY DIMINISH OVERNIGHT AS THE SFC LOW CONTINUES TO FILL AND
THE PRESSURE GRADIENT WEAKENS.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WOLTERS
SHORT TERM...53
LONG TERM...63
AVIATION...WOLTERS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
731 AM EDT WED JUN 26 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 338 AM EDT WED JUN 26 2013
A SHORTWAVE CURRENTLY OVER THE DAKOTAS IS PRODUCING A LINE OF
THUNDERSTORMS ALONG THE SD/MN AND ND/MN BORDERS. THUNDERSTORMS
ACTIVITY HAS BEEN WANING OVER THE LAST COUPLE OF HOURS...BUT
WIDESPREAD PRECIP IS STILL OCCURRING. THIS SHORTWAVE WILL MOVE OVER
THE CWA THROUGH THE END OF THE SHORT TERM /12 THU/. CONTINUED TO
SHOW POPS ALONG AND AHEAD OF THE SHORTWAVE GIVEN EXTENT OF CURRENT
ACTIVITY. THERE IS AN OUTSIDE CHANCE AT A STRONGER STORM OR TWO
TODAY...WITH SOME STRONGER WINDS AND SMALL HAIL...GIVEN AROUND
1000J/KG OF CAPE...WEAK SHEAR AND A GOOD AMOUNT OF DRY AIR IN
FORECAST SOUNDINGS.
EXPECT HIGHS FROM THE UPPER 60S RIGHT ALONG LAKE SUPERIOR TO THE MID
80S INTERIOR. TONIGHT EXPECT LOWS IN THE 50S AND 60S.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 338 AM EDT WED JUN 26 2013
NAM SHOWS A 500 MB RIDGE OVER THE ROCKIES WITH TROUGHING IN THE
EASTERN U.S. 12Z THU. THE 500 MB RIDGE AMPLIFIES THIS PERIOD WITH
TROUGHING DIGGING IN THE EASTERN HALF OF THE U.S. NAM KEEPS SOME
850-500 MB Q-VECTOR CONVERGENCE OVER THE AREA 12Z THU ONWARD THROUGH
THE REST OF THIS FORECAST PERIOD WITH SOME MOISTURE AROUND. WILL
CONTINUE WITH THE SLIGHT CHANCE TO CHANCE POPS FOR THIS PERIOD. DOES
NOT LOOK LIKE A TOTAL WASHOUT AND CONVECTION WILL BE SCATTERED AT
BEST. OTHERWISE...DID NOT MAKE TOO MANY CHANGES TO THE GOING
FORECAST EXCEPT DID WARM TEMPERATURES UP A BIT ON THU AS 850 MB
TEMPERATURES OF 16C MIXED DOWN TO THE SFC GIVES ME HIGH IN THE LOWER
TO MID 80S. COLDER AIR ARRIVES FOR FRI THEN.
IN THE EXTENDED...A STRONG 500 MB RIDGE SETS UP IN THE ROCKIES
LEADING TO A HEAT WAVE IN THE WESTERN U.S. 12Z SAT WHILE A DEEP 500
MB TROUGH DIGS INTO THE EASTERN U.S. THE 500 MB PATTERN CHANGES VERY
LITTLE IN THE EXTENDED WITH THE TROUGH REMAINING OVER THE UPPER
GREAT LAKES REGION THROUGH TUE WITH PATTERN AMPLIFICATION. WHAT THIS
MEANS IS HEAT IN THE WESTERN U.S. AND COLDER THAN NORMAL
TEMPERATURES OVER THE AREA FOR AN EXTENDED PERIOD OF TIME. AFTER
SAT...LOOKS DRY FOR THE EXTENDED PERIOD EVEN WITH TROUGHING OVERHEAD
AND SFC RIDGING. WILL GO DRY SAT NIGHT ONWARD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 730 AM EDT WED JUN 26 2013
THERE IS SOME LIGHT MORNING FOG AT SAW /AND OCCASIONALLY AT
IWD/...BUT THIS FOG SHOULD BURN OFF QUICKLY. OTHERWISE...EXPECT VFR
CONDITIONS THROUGH AT LEAST MID AFTN. APPROACHING DISTURBANCE SHOULD
BRING SHRA/SCT TSRA INTO UPPER MI LATER THIS AFTN. INCLUDED
SHRA/VCTS AND MVFR CONDITIONS AT KIWD/KCMX LATE AFTN/EARLY EVENING
AND AT KSAW MID TO LATE EVENING. SHRA/SCT TSRA SHOULD BE IN THE AREA
FOR SEVERAL HRS. PROVIDED RAIN DOES OCCUR AT KCMX...CONDITIONS MAY
FALL TO IFR OR LWR ONCE PCPN ENDS THIS EVENING AS WINDS SHOULD HAVE
SOME UPSLOPE COMPONENT OFF THE LAKE. FOLLOWED HRRR MORE CLOSELY FOR
PRECIP TIMING THIS AFTERNOON/EVENING AS IT HAS BEEN PERFORMING
FAIRLY WELL WITH CONVECTION.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 338 AM EDT WED JUN 26 2013
OVERALL...WINDS ARE EXPECTED TO BE BELOW 20KTS THROUGH THE PERIOD AS
THE PRESSURE PATTERN REMAINS FAIRLY WEAK ACROSS THE AREA. WITH THE
WARM MOIST AIR OVER THE UPPER GREAT LAKES...WILL CONTINUE TO MENTION
PATCHY/AREAS OF FOG THROUGH TONIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...TITUS
LONG TERM...07
AVIATION...TITUS
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
156 AM EDT WED JUN 26 2013
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 430 PM EDT TUE JUN 25 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A LOW AMPLITUDE PATTERN WITH A
TROUGH INTO THE PAC NW AND A RIDGE FROM THE UPPER MS VALLEY INTO
MANITOBA. THE MAIN UPSTREAM SHORTWAVE TROUGH EXTENDED FROM ERN
MONTANA INTO WRN SD. AT THE SFC...A WEAK RIDGE AND LIGHT PRES
GRADIENT PREVAILED OVER THE THE REGION ALLOWING PROMINENT LAKE
BREEZES TO DEVELOP. CAPPING HAS BEEN STRONG ENOUGH TO SUPPRESS
CONVECTION THROUGH 20Z DESPITE LOW LEVEL CONV...INLAND MLCAPE VALUES
TO NEAR 1500 J/KG AND CU/TCU LINE DEVELOPMENT. MIXING HAS ALSO BEEN
STRONG ENOUGH TO DROP DEWPOINTS INTO THE MID AND UPPER 50S NEAR THE WI
BORDER
TONIGHT...POTENTIAL REMAINS FOR SOME ISOLD SHRA/TSRA
DEVELOPMENT...MAINLY OVER THE SOUTH NEAR THE LAKE BREEZE BOUNDARIES.
WITH THE LOSS OF DAYTIME HEATING...ANY PCPN CHANCES WILL ALSO
DIMINISH THIS EVENING. EVEN WITH FAVORABLE RADIATIONAL COOLING
OVERNIGHT...ENOUGH LOW LEVEL MOISTURE REMAINS TO KEEP MIN TEMPS FROM
DROPPING MUCH BELOW 60F. SOME PATCHY FOG MAY ALSO DEVELOP.
WED...THE NRN PLAINS SHRTWV AND ASSOCIATED SFC TROUGH MOVING INTO
THE WRN LAKES WILL BE THE FOCUS FOR SHRA/TSRA DEVELOPMENT. THE
MODELS WERE IN RELATIVELY GOOD AGREEMENT BRINGING THE HIGHER PCPN
CHANCES INTO THE WEST HALF OF THE CWA DURING THE AFTERNOON. THE
AIRMASS OVER REGION SHOULD AGAIN ALLOW TEMPS TO CLIMB INTO THE LOWER
80S INLAND AND BEFORE LAKE BREEZES TAKE OVER. MLCAPE VALUES MAY
AGAIN CLIMB TO AROUND 1500 J/KG BUT RELATIVELY MODEST SHEAR VALUES
WILL LIMIT STRONG/SEVERE STORM POTENTIAL.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 430 PM EDT TUE JUN 25 2013
OVERALL PATTERN WILL EVOLVE INTO AN AMPLIFIED ONE FOR LATE JUNE
STANDARDS DURING THE LATE WEEK PERIOD WITH INTENSE UPPER RIDGING
DEVELOPING OVER THE WESTERN U.S. AND TROUGHING DEVELOPING OVER THE
GREAT LAKES AND EASTERN U.S. AS HAS BEEN THE CASE OVER THE LAST
SEVERAL DAYS TIMING OF A BETTER PRECIP CHANCES DURING THE NEXT
COUPLE OF DAYS WILL REMAIN A CHALLENGE. CONFIDENCE IS PRETTY HIGH
THAT ALL AREAS WILL SEE AT LEAST SOME RAINFALL BETWEEN THE WEDNESDAY
NIGHT THROUGH SATURDAY TIME PERIOD. HOWEVER...MORE OF THAT TIME WILL
BE DRY RATHER THAN RAINY.
WHILE SCATTERED POPS SEEM THE WAY TO GO FOR THIS TIME PERIOD...WILL
GO WITH SLIGHTLY HIGHER POPS DURING THE WED NIGHT TIME PERIOD AS
SHORTWAVE ENERGY BEGINS TO CARVE OUT UPPER TROUGHING OVER THE GREAT
LAKES. WILL ALSO GO ON THE HIGHER END OF CHANCE POPS FOR FRIDAY INTO
SATURDAY AS MAIN TROUGH AXIS MOVES THROUGH THE AREA. A SCATTERING
OF POPS DURING THE OTHER PERIODS SEEMS REASONABLE.
WITH LIMITED INSTABILITY AND SHEAR EXPECTED...THUNDER CHANCES WILL BE
MORE IN THE ISOLATED TO SLIGHT CHANCE RANGE.
HIGH PRESSURE AND DRIER AIR SHOULD BEGIN PUSHING INTO THE AREA FROM
THE NORTH BY LATE IN THE DAY SATURDAY ENDING THE RAIN CHANCES.
UPPER TOUGHING WILL REMAIN OVER THE AREA INTO EARLY NEXT WEEK
KEEPING TEMPERATURES AT TO JUST SLIGHTLY BELOW NORMAL THROUGH THE
WEEKEND INTO MONDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 155 AM EDT WED JUN 26 2013
THERE MAY BE SOME RADIATIONAL FOG (MVFR VIS) OVERNIGHT AT KIWD/KSAW
AND PERHAPS KCMX. OTHERWISE...EXPECT VFR CONDITIONS THRU AT LEAST
MID AFTN. APPROACHING DISTURBANCE SHOULD BRING SHRA/SCT TSRA INTO
UPPER MI LATER THIS AFTN. INCLUDED SHRA/VCTS AND MVFR CONDITIONS AT
KIWD/KCMX LATE AFTN/EARLY EVENING AND AT KSAW MID TO LATE EVENING.
SHRA/SCT TSRA SHOULD BE IN THE AREA FOR SEVERAL HRS. PROVIDED RAIN
DOES OCCUR AT KCMX...CONDITIONS MAY FALL TO IFR OR LWR ONCE PCPN
ENDS THIS EVENING AS WINDS SHOULD HAVE SOME UPSLOPE COMPONENT OFF
THE LAKE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 430 PM EDT TUE JUN 25 2013
OVERALL...WINDS ARE EXPECTED TO BE BELOW 20KTS THROUGH THE PERIOD AS
THE PRESSURE PATTERN REMAINS FAIRLY WEAK ACROSS THE AREA. WITH THE
WARM MOIST AIR OVER THE UPPER GREAT LAKES...WILL CONTINUE TO MENTION
PATCHY/AREAS OF FOG THROUGH WEDNESDAY NIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...MZ
AVIATION...ROLFSON
MARINE...JLB
AREA FORECAST DISCUSSION
NWS DULUTH MN
103 PM CDT WED JUN 26 2013
.AVIATION...
THUNDERSTORMS...CONTAINING HEAVY RAINFALL...WILL ACCOMPANY A
FRONTAL BOUNDARY AS IT CROSSES OVER THE MINNESOTA ARROWHEAD AND
NORTHERN WISCONSIN THIS AFTERNOON. THE STRONGEST STORMS...LASTING
ABOUT AN HOUR...WILL BE FOUND IN THE HAYWARD AREA BETWEEN 19Z-21Z
THIS AFTERNOON. A FEW ADDITIONAL SHOWERS OR THUNDERSTORMS WILL BE
POSSIBLE THOUGH THE AFTERNOON ACROSS NORTHEAST MINNESOTA WHERE
PERIODS OF MVFR CEILINGS AROUND 2 KFT WILL PERSIST. HAVE KEPT
VCTS/VCSH AT ALL MINNESOTA TERMINALS FOR THE REMAINDER OF THE DAY
WITH IMPROVING CEILINGS THROUGH THE AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 1045 AM CDT WED JUN 26 2013/
UPDATE...
THE FOCUS FOR THIS UPDATE IS THE POTENTIAL OF SHOWERS AND
THUNDERSTORMS THROUGH THIS EVENING. THE ONLY REMAINING SHOWERS AND
STORMS AT THE TIME OF THIS UPDATE ARE NEAR A VORTEX MOVING
NORTHEAST NEAR IN NORTHERN ST. LOUIS COUNTY. REDEVELOPMENT ALONG
AND AHEAD OF TROUGH OF LOW PRESSURE MOVING THROUGH THE NORTHLAND
TODAY IS LIKELY...AT LEAST IN NW WISCONSIN AND THE MINNESOTA
ARROWHEAD. THE HRRR HAS BEEN CONSISTENTLY INDICATING A BAND OF
STORMS FORMING IN NW WISCONSIN BY EARLY THIS AFTERNOON AND EXITING
MID TO LATE THIS AFTERNOON. I ALTERED PCPN CHANCES TO REFLECT THE
HIGHEST CHANCES ACROSS THE EASTERN FORECAST AREA...WHILE LOWERED
CHANCES ACROSS THE WEST. WHILE THERE SHOULD BE A GENERAL
DECREASING CHANCE OF PCPN FROM WEST TO EAST THIS AFTERNOON INTO
THIS EVENING...SOME MODELS ARE INDICATING SOME SHOWERS AND STORMS
MOVING INTO THE WESTERN FORECAST AREA FROM NW MINNESOTA THIS
EVENING AND OVERNIGHT...SO I KEPT LOW CHANCES OVER JUST ABOUT ALL
OF THE FORECAST AREA THROUGH AT LEAST THIS EVENING. IT STILL
APPEARS WE COULD SEE SOME STRONG...MAYBE SEVERE STORMS...ACROSS NW
WISCONSIN. WHILE THERE MAY BE LOTS OF CAPE...WITH THE NAM12
INDICATING AT LEAST 4000 J/KG OF MOST UNSTABLE CAPE ALONG THE CAPE
AXIS...THE LIMITING FACTOR FOR SEVERE WEATHER WILL LIKELY BE WIND
SHEAR. THE NAM12 IS INDICATING LOW BULK SHEAR...LESS THAN 20 KNOTS
FOR 0-6KM...ALONG THE CAPE AXIS. HOWEVER...WE WILL NEED TO WATCH
CLOSELY FOR DEVELOPMENT AND SEE IF THE NAM12 WIND SHEAR HOLDS
TRUE. IF THERE IS MORE WIND SHEAR THAN THE NAM12 SUGGESTS...THEN
SOME STORMS COULD MORE EASILY BECOME SEVERE.
AS FAR AS TEMPERATURES TODAY...THE LATEST MOS GUIDANCE IS MUCH
WARMER IN SOME AREAS COMPARED TO THE PREVIOUS FORECAST. I INCREASED
TEMPERATURES BY UP TO SEVERAL DEGREES...NOTABLE ACROSS INLAND NW
WISCONSIN.
PREV DISCUSSION... /ISSUED 316 AM CDT WED JUN 26 2013/
SHORT TERM...SHORT TERM CONCERNS IS MOVEMENT OF THUNDERSTORM
COMPLEX IN NW MN THIS MORNING AND EFFECT ON FORECAST AREA. SECOND
CONCERN IS TSTM CHANCES.
CURRENT SURFACE ANALYSIS INDICATES AREA OF THUNDERSTORMS ACROSS NW
MN MOVING EAST-NORTHEAST. CAPES RANGE FROM 2500-4000 WITH THE
STORMS WITH THE STRONGEST STORMS JUST EAST OF FARGO. SHEAR IS
WEAKER TOWARD THE WESTERN AREAS OF THE FORECAST AREA BUT CAPES ARE
STILL ON THE HIGH SIDE ALONG WITH PLENTY OF MOISTURE. THE PRECIP
AREA HAS STARTED TO CLIP NW KOOCHCHING COUNTY AND WILL SPREAD EAST
EARLY THIS MORNING. THE PRECIP WILL DECREASE IN INTENSITY AND
COVERAGE AS IT MOVES THROUGH NE MN.
THE NEXT CONCERN FOR THE SHORT TERM IS THUNDERSTORM DEVELOPMENT
THIS AFTERNOON. THERE WILL BE SOME DEBRIS CLOUDS LEFT OVER FROM
THIS MORNING`S STORMS ACROSS NW MN. THE QUESTION FOR THE FORECAST
IS HOW MUCH SUN WILL BE SEEN LATE THIS MORNING AND THIS AFTERNOON.
BASED ON CURRENT TRENDS...THERE COULD BE SOME SUN THIS AFTERNOON
ACROSS EASTERN PORTIONS OF NE MN AND ALL NW WI. THIS WILL INCREASE
THE INSTABILITY THIS AFTERNOON OVER THAT REGION SO WILL KEEP
CURRENT POPS FOR TSTMS. SPC HAS THE SOUTHERN TIER OF NW WI
COUNTIES IN A SLIGHT RISK AREA FOR THIS AFTERNOON AND TONIGHT.
WEAK HIGH PRESSURE WILL BUILD INTO THE WESTERN PORTION OF MN AREA
TONIGHT ENDING THE PRECIP TONIGHT AND WEDNESDAY. THE ONLY
EXCEPTION WILL BE OVER THE ARROWHEAD WHERE THE TROUGH WILL KEEP
THE POSSIBILITY OF THUNDERSTORMS ACROSS THAT REGION THROUGH
THURSDAY.
LONG TERM...THURSDAY NIGHT THROUGH TUESDAY
THURSDAY NIGHT AND FRIDAY WE WILL HAVE A STATIONARY FRONT DRAPED
ACROSS THE ARROWHEAD REGION. THIS WILL BE ASSOCIATED WITH SOME
CHANNELED VORT MAXES IN THE STRONG NORTHWEST FLOW OVER THE
REGION...ON THE BACK SIDE OF THE UPPER LEVEL TROUGH OVER THE EAST
COAST AND THE STRONG RIDGE OVER THE ROCKIES. THIS WARRANTS SOME
HIGH CHANCE TO LOW END LIKELY POPS OVER THE ARROWHEAD REGION
THURSDAY NIGHT AND FRIDAY...ALONG WITH COOLER FRIDAY HIGHS IN THE
LOW 70S. ELSEWHERE HIGHS SHOULD RISE INTO THE MID TO UPPER 70S.
FRIDAY NIGHT AND SATURDAY THE FRONT IS PUSHED SOUTH AS A COLD FRONT
ALONG WITH A MORE VIGOROUS SHORTWAVE THAT DIGS DOWN ACROSS MN AND
WI. THIS SHIFTS OUR POPS SOUTH ACROSS THE REGION...HAVE HAVE PUT
MAINLY CHANCE POPS THROUGH THE PERIOD. SATURDAY LOOKS COOLER WITH
HIGHS ONLY IN THE LOW TO MID 70S...DEPENDING ON HOW MUCH SUNSHINE
CAN GET THROUGH.
SATURDAY NIGHT THROUGH SUNDAY AND INTO MONDAY WE MOVE INTO A DRY
PERIOD AS THE SHORTWAVE THAT MOVED THROUGH ON SATURDAY DIGS SOUTH
AND LEAVES US WITH SOME RIDGING ALOFT AND WEAK RIDGING AT THE
SURFACE AS WELL. THE SHORTWAVE EVENTUALLY CUTS OFF OVER THE DEEP
SOUTH STATES...AND TOGETHER WITH THE RIDGE OUT WEST REALLY SLOWS
DOWN OUR UPPER LEVEL PATTERN. THUS...WHILE I DO HAVE SOME SMALL
CHANCE POPS OUT FOR LATER MONDAY THROUGH TUESDAY...THEY ARE PRETTY
MINOR AND CONFIDENCE IS NOT TERRIBLY HIGH. HIGHS SHOULD RISE UP
INTO THE UPPER 70S TO NEAR 80.
&&
.POINT TEMPS/POPS...
DLH 59 80 57 75 / 30 40 10 40
INL 60 79 58 75 / 30 40 20 40
BRD 62 81 60 79 / 20 10 10 20
HYR 61 80 57 77 / 40 40 10 40
ASX 56 76 56 72 / 50 30 20 70
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
AVIATION...GRANING
AREA FORECAST DISCUSSION
NWS DULUTH MN
1045 AM CDT WED JUN 26 2013
.UPDATE...
THE FOCUS FOR THIS UPDATE IS THE POTENTIAL OF SHOWERS AND
THUNDERSTORMS THROUGH THIS EVENING. THE ONLY REMAINING SHOWERS AND
STORMS AT THE TIME OF THIS UPDATE ARE NEAR A VORTEX MOVING
NORTHEAST NEAR IN NORTHERN ST. LOUIS COUNTY. REDEVELOPMENT ALONG
AND AHEAD OF TROUGH OF LOW PRESSURE MOVING THROUGH THE NORTHLAND
TODAY IS LIKELY...AT LEAST IN NW WISCONSIN AND THE MINNESOTA
ARROWHEAD. THE HRRR HAS BEEN CONSISTENTLY INDICATING A BAND OF
STORMS FORMING IN NW WISCONSIN BY EARLY THIS AFTERNOON AND EXITING
MID TO LATE THIS AFTERNOON. I ALTERED PCPN CHANCES TO REFLECT THE
HIGHEST CHANCES ACROSS THE EASTERN FORECAST AREA...WHILE LOWERED
CHANCES ACROSS THE WEST. WHILE THERE SHOULD BE A GENERAL
DECREASING CHANCE OF PCPN FROM WEST TO EAST THIS AFTERNOON INTO
THIS EVENING...SOME MODELS ARE INDICATING SOME SHOWERS AND STORMS
MOVING INTO THE WESTERN FORECAST AREA FROM NW MINNESOTA THIS
EVENING AND OVERNIGHT...SO I KEPT LOW CHANCES OVER JUST ABOUT ALL
OF THE FORECAST AREA THROUGH AT LEAST THIS EVENING. IT STILL
APPEARS WE COULD SEE SOME STRONG...MAYBE SEVERE STORMS...ACROSS NW
WISCONSIN. WHILE THERE MAY BE LOTS OF CAPE...WITH THE NAM12
INDICATING AT LEAST 4000 J/KG OF MOST UNSTABLE CAPE ALONG THE CAPE
AXIS...THE LIMITING FACTOR FOR SEVERE WEATHER WILL LIKELY BE WIND
SHEAR. THE NAM12 IS INDICATING LOW BULK SHEAR...LESS THAN 20 KNOTS
FOR 0-6KM...ALONG THE CAPE AXIS. HOWEVER...WE WILL NEED TO WATCH
CLOSELY FOR DEVELOPMENT AND SEE IF THE NAM12 WIND SHEAR HOLDS
TRUE. IF THERE IS MORE WIND SHEAR THAN THE NAM12 SUGGESTS...THEN
SOME STORMS COULD MORE EASILY BECOME SEVERE.
AS FAR AS TEMPERATURES TODAY...THE LATEST MOS GUIDANCE IS MUCH
WARMER IN SOME AREAS COMPARED TO THE PREVIOUS FORECAST. I INCREASED
TEMPERATURES BY UP TO SEVERAL DEGREES...NOTABLE ACROSS INLAND NW
WISCONSIN.
&&
.PREV DISCUSSION... /ISSUED 659 AM CDT WED JUN 26 2013/
AVIATION...
BAND OF WEAKENING CONVECTION CURRENTLY SWEEPING ACROSS THE
TERMINALS THIS MORNING. LINGERING STORMS BRINGING IFR TO MVFR CIGS
AND VSBYS AT THEY MOVE THROUGH EACH LOCATION. KHYR...WHICH HAS
BEEN IN THE CLEAR ALL NIGHT HAS DEVELOPED SOME MVFR FOG WHICH
SHOULD CLEAR BY 13Z. KDLH ALSO DEVELOPED SOME EARLY MORNING
FOG...WHICH SHOULD ALSO CLEAR IN NEXT COUPLE HOURS. ADDITIONAL
THUNDERSTORM DEVELOPMENT IS EXPECTED THIS AFTERNOON...MAINLY FOR
KINL...KHIB...KDLH AND KHYR. TIMING AND LOCATIONS UNCERTAIN SO
HAVE GONE WITH ONLY VCTS FOR NOW...BUT WILL HAVE TO REFINE WITH
LATER ISSUANCES. BY LATE AFTERNOON WEAK COLD FRONT TO MOVE THROUGH
THE AREA AND TURN WINDS TO WEST...ALSO ENDING TSRA CHANCES. LE
PREV DISCUSSION... /ISSUED 316 AM CDT WED JUN 26 2013/
SHORT TERM...SHORT TERM CONCERNS IS MOVEMENT OF THUNDERSTORM
COMPLEX IN NW MN THIS MORNING AND EFFECT ON FORECAST AREA. SECOND
CONCERN IS TSTM CHANCES.
CURRENT SURFACE ANALYSIS INDICATES AREA OF THUNDERSTORMS ACROSS NW
MN MOVING EAST-NORTHEAST. CAPES RANGE FROM 2500-4000 WITH THE
STORMS WITH THE STRONGEST STORMS JUST EAST OF FARGO. SHEAR IS
WEAKER TOWARD THE WESTERN AREAS OF THE FORECAST AREA BUT CAPES ARE
STILL ON THE HIGH SIDE ALONG WITH PLENTY OF MOISTURE. THE PRECIP
AREA HAS STARTED TO CLIP NW KOOCHCHING COUNTY AND WILL SPREAD EAST
EARLY THIS MORNING. THE PRECIP WILL DECREASE IN INTENSITY AND
COVERAGE AS IT MOVES THROUGH NE MN.
THE NEXT CONCERN FOR THE SHORT TERM IS THUNDERSTORM DEVELOPMENT
THIS AFTERNOON. THERE WILL BE SOME DEBRIS CLOUDS LEFT OVER FROM
THIS MORNING`S STORMS ACROSS NW MN. THE QUESTION FOR THE FORECAST
IS HOW MUCH SUN WILL BE SEEN LATE THIS MORNING AND THIS AFTERNOON.
BASED ON CURRENT TRENDS...THERE COULD BE SOME SUN THIS AFTERNOON
ACROSS EASTERN PORTIONS OF NE MN AND ALL NW WI. THIS WILL INCREASE
THE INSTABILITY THIS AFTERNOON OVER THAT REGION SO WILL KEEP
CURRENT POPS FOR TSTMS. SPC HAS THE SOUTHERN TIER OF NW WI
COUNTIES IN A SLIGHT RISK AREA FOR THIS AFTERNOON AND TONIGHT.
WEAK HIGH PRESSURE WILL BUILD INTO THE WESTERN PORTION OF MN AREA
TONIGHT ENDING THE PRECIP TONIGHT AND WEDNESDAY. THE ONLY
EXCEPTION WILL BE OVER THE ARROWHEAD WHERE THE TROUGH WILL KEEP
THE POSSIBILITY OF THUNDERSTORMS ACROSS THAT REGION THROUGH
THURSDAY.
LONG TERM...THURSDAY NIGHT THROUGH TUESDAY
THURSDAY NIGHT AND FRIDAY WE WILL HAVE A STATIONARY FRONT DRAPED
ACROSS THE ARROWHEAD REGION. THIS WILL BE ASSOCIATED WITH SOME
CHANNELED VORT MAXES IN THE STRONG NORTHWEST FLOW OVER THE
REGION...ON THE BACK SIDE OF THE UPPER LEVEL TROUGH OVER THE EAST
COAST AND THE STRONG RIDGE OVER THE ROCKIES. THIS WARRANTS SOME
HIGH CHANCE TO LOW END LIKELY POPS OVER THE ARROWHEAD REGION
THURSDAY NIGHT AND FRIDAY...ALONG WITH COOLER FRIDAY HIGHS IN THE
LOW 70S. ELSEWHERE HIGHS SHOULD RISE INTO THE MID TO UPPER 70S.
FRIDAY NIGHT AND SATURDAY THE FRONT IS PUSHED SOUTH AS A COLD FRONT
ALONG WITH A MORE VIGOROUS SHORTWAVE THAT DIGS DOWN ACROSS MN AND
WI. THIS SHIFTS OUR POPS SOUTH ACROSS THE REGION...HAVE HAVE PUT
MAINLY CHANCE POPS THROUGH THE PERIOD. SATURDAY LOOKS COOLER WITH
HIGHS ONLY IN THE LOW TO MID 70S...DEPENDING ON HOW MUCH SUNSHINE
CAN GET THROUGH.
SATURDAY NIGHT THROUGH SUNDAY AND INTO MONDAY WE MOVE INTO A DRY
PERIOD AS THE SHORTWAVE THAT MOVED THROUGH ON SATURDAY DIGS SOUTH
AND LEAVES US WITH SOME RIDGING ALOFT AND WEAK RIDGING AT THE
SURFACE AS WELL. THE SHORTWAVE EVENTUALLY CUTS OFF OVER THE DEEP
SOUTH STATES...AND TOGETHER WITH THE RIDGE OUT WEST REALLY SLOWS
DOWN OUR UPPER LEVEL PATTERN. THUS...WHILE I DO HAVE SOME SMALL
CHANCE POPS OUT FOR LATER MONDAY THROUGH TUESDAY...THEY ARE PRETTY
MINOR AND CONFIDENCE IS NOT TERRIBLY HIGH. HIGHS SHOULD RISE UP
INTO THE UPPER 70S TO NEAR 80.
&&
.POINT TEMPS/POPS...
DLH 80 59 80 57 / 50 30 40 10
INL 82 60 79 58 / 70 30 40 20
BRD 86 62 81 60 / 30 20 10 10
HYR 86 61 80 57 / 60 40 40 10
ASX 84 56 76 56 / 50 50 30 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...GROCHOCINSKI
AREA FORECAST DISCUSSION
NWS DULUTH MN
1231 AM CDT WED JUN 26 2013
.AVIATION...06Z TAF ISSUANCE...
EARLY MORNING BR/FG EXPECTED AT KHYR/KDLH/KHIB WITH POTENTIAL FOR
CEILINGS TO LOWER TO IFR/LIFR. NOT AS CONFIDENT ON FG/BR AT KHIB
HOWEVER CLIMO FAVORS AT LEAST A TEMPO IFR VIS. OTHERWISE MAIN
FEATURE WILL BE AREAL COVERAGE/TIMING OF CONVECTION WITH
APPROACHING FRONTAL SYSTEM. MDLS STILL VARY ON TIMING OF MAIN AXIS
OF MOISTURE/LIFT SO HAVE MAINTAINED THE PROB30 WORDING FOR ALL
SITES. APPEARS THAT A 6HR WINDOW OF OPPORTUNITY WILL EXIST BEFORE
FROPA/WINDSHIFT TO SW AND WEST OCCURS LATER IN THE AFTN...EXCEPT
AT KHYR WHERE FROPA WILL BE LATER.
&&
.PREV DISCUSSION... /ISSUED 1100 PM CDT TUE JUN 25 2013/
UPDATE...ADDED PATCHY FOG TO WISCONSIN ZONES AND NEAR TWIN
PORTS AFTER 08Z PER SFC T/TD SPREADS AT THIS HOUR. LATEST HRRR 3KM
FCST OF LOWERING VISIBILITY ALSO SUPPORTS THIS IDEA ALONG WITH
PERSISTENCE FROM PREVIOUS NIGHTS ALTHOUGH EVENTUALLY MORE HIGH LVL CLOUD
COVER WILL WORK ITS WAY IN FROM THE WEST. CONVECTIVE COMPLEXES
CONTINUE NEAR SFC LOW/TROF OVER ERN NODAK/MN BORDER IN AN AREA OF
MAXIMUM 85H MSTR TRANSPORT AND WELL DEFINED 85/30H THICKNESS
DIFFLUENCE. 03Z HRRR SIM REFL BRINGS REMNANTS OF THIS AREA INTO
NWRN CWA AFTER 08Z WITH A SECONDARY LINE MOVING INTO WRN/SWRN CWA
AROUND 15Z. NSSL WRF MAKES MORE OF A CASE FOR CONVECTION TO
MAINTAIN SOME ORGANIZATION AS IT MOVES INTO CWA AND HEADS TOWARDS
TWIN PORTS AROUND 12Z. USING PROGRESSION OF MID LVL SHEAR AXIS
PUTS HIGHEST POPS OVER ERN CWA WED AFTN. INCREASED POPS IN THIS
AREA. ALSO RAISED MAX TEMPS FROM TWIN PORTS WEST AS IT APPEARS
THAT PROGRESSION OF WESTERLY FLOW IN MIXING LAYER MAY ALLOW SOME
LATE DAY WARMING.
PREV DISCUSSION... /ISSUED 703 PM CDT TUE JUN 25 2013/
UPDATE...UPDATE TO DELAY ARRIVAL OF POPS A FEW HRS AS MAIN FOCUS
OF ACTIVITY IS OCCURRING WITHIN 85H THETAE AXIS ASSOCIATED WITH SFC
LOW/TROF OVER CENTRAL DAKOTAS. AS STATED IN PRIOR DISCUSSION
ATMOSPHERE IS QUITE UNSTABLE OVER CWA. WITH BDRY LYR DECOUPLING...SPC
MESO SHOWS AREAL COVERAGE OF SBCIN INCREASING. BOTH NSSL WRF-ARW
AND SPC WRF-NMM SIM REFLECTIVITY PRODUCTS DEPICT CURRENT
SITUATION DECENTLY REGARDING NODAK LINE OF CONVECTION. FCST
INDICATES CONSIDERABLE WEAKENING OF THE LINE AFTER IT CROSSES
NODAK/MN STATE LINE AND ENTERS WRN CWA BY 09Z. WILL MONITOR
ACTIVITY TO THE WEST THIS EVENING AND AMEND ACCORDINGLY.
PREV DISCUSSION... /ISSUED 649 PM CDT TUE JUN 25 2013/
AVIATION...00Z TAF ISSUANCE...
VFR CONDITIONS ACROSS NE MINNESOTA AND NW WISCONSIN WILL CONTINUE
THIS EVENING. BR AND/OR FG IS POSSIBLE LATE TONIGHT AND EARLY
WEDNESDAY MORNING. THE MOST LIKELY LOCATIONS FOR FG ARE KDLH AND
KHYR. STORMS IN THE NORTHERN PLAINS WILL APPROACH THE WRN CWA
AFTER MIDNIGHT. MOST LIKELY TIME FOR RW/TRW AT KINL/KBRD WOULD BE
LATE MORNING/EARLY AFTN...WITH AFTN HRS MORE LIKELY NEAR
KHIB/KDLH/KHYR. WILL TRY TO NARROW WINDOW IN NEXT FCST AT 06Z.
PREV DISCUSSION... /ISSUED 315 PM CDT TUE JUN 25 2013/
SHORT TERM...TONIGHT AND WEDNESDAY...
AT 300 PM VISIBLE SATELLITE IMAGERY
DEPICTED MOSTLY SUNNY TO PARTLY CLOUDY SKIES ACROSS THE NORTHLAND.
TEMPERATURES RANGED FROM 87 AT KHIB TO 85 AT KBRD...83 AT
KHYR...85 AT KDLH. COOLER READINGS WERE FOUND NEAR LAKE SUPERIOR
WITH 70 DEGREES AT KDYT/DULUTH HARBOR...67 LAKESIDE AT SILVER BAY
AND A CHILLY 50 DEGREES AT GRAND MARAIS.
THE FORECAST AREA WILL REMAIN SITUATED BETWEEN A H85 LOW/SFC TROUGH
APPROACHING FROM THE DAKOTAS...AND A WARM FRONT LIFTING INTO
NORTHERN WISCONSIN OVERNIGHT. ALTHOUGH INSTABILITY IS HIGH...LATEST
MODEL RUNS ARE IN AGREEMENT THAT THERE IS MUCH LESS CONVECTION
ASSOCIATED WITH THESE BOUNDARIES AS THEY PASS OVER THE REGION THROUGH
THE NEXT 24 HRS...MAINLY DUE TO THE LACK OF MID LEVEL MOISTURE.
ALTHOUGH THE FRONT IS EXPECTED TO TRIGGER SCATTERED SHOWERS AND
THUNDERSTORMS...HAVE DECREASED POPS OVERNIGHT AND WEDNESDAY FROM
PREVIOUS FORECAST DUE TO A LACK OF MID LEVEL MOISTURE TO SUPPORT
WIDESPREAD ACTIVITY. HOWEVER...THE ATMOSPHERE REMAINS VERY
UNSTABLE WITH SUFFICIENT CAPE TO SUPPORT STRONG TO POSSIBLY
SEVERE STORMS OVERNIGHT.
THE SFC BOUNDARY WILL PUSH OUT OF THE DAKOTAS LATE TONIGHT...REACH
NORTH CENTRAL MINNESOTA WEDNESDAY MORNING...THEN TRACK ACROSS THE
MINNESOTA ARROWHEAD AND NORTHERN WISCONSIN ZONES WEDNESDAY
EVENING. AS THE FRONT PASSES...EXPECT WINDS TO SWITCH OUT OF THE
NORTHWEST. GUSTS TO 20 MPH WILL BE FOUND IN THE BRAINERD LAKES
AREA...MAINLY LATE IN THE DAY. TEMPERATURES WILL TOP OUT IN THE
LOW 80S.
HAVE
PULLED BACK ON POPS TONIGHT AND WEDNESDAY TO ONLY HIGH CHANCE POPS
WITH SCATTERED WORDING. HOWEVER...NAM BUFR SOUNDINGS AND RUC
PROFILES SHOW SUFFICIENT CAPE TO SUPPORT STRONG TO POSSIBLY SEVERE
STORMS OF THE ONES THAT WILL DEVELOP.
LONG TERM [WEDNESDAY NIGHT - MONDAY]
A WEAK STATIONARY FRONT WILL STRETCH FROM THE CENTRAL CANADIAN
PROVINCES...OVER THE GREAT LAKES...AND INTO THE EASTERN UNITED
STATES DURING THE BEGINNING OF THE PERIOD. ITS PROXIMITY AND THE NW
FLOW OVER THE NORTHLAND WILL COULD HELP CAUSE PRIMARILY DAYTIME
HEATING DRIVEN SHOWERS AND THUNDERSTORMS. THE NORTH AND EASTERN
FORECAST AREA HAVE THE BEST CHANCE OF PCPN. THE STATIONARY FRONT
SHOULD THEN SWING THROUGH THE NORTHLAND LATE THIS WEEK AS A WEAK
COLD FRONT...CONTINUING THE LOW CHANCES OF SHOWERS AND THUNDERSTORMS
INTO SATURDAY EVENING. THE MODELS ARE INCREASING INDICATING THAT
HIGH PRESSURE WILL MOVE INTO THE UPPER MIDWEST EARLY NEXT WEEK AND
LIKELY PROVIDE DRY WEATHER FOR SUNDAY AND MONDAY. TEMPERATURES
SHOULD BE SLIGHTLY ABOVE NORMAL THURSDAY...NEAR NORMAL
FRIDAY...SLIGHTLY BELOW NORMAL SATURDAY...AND THEN RETURNING TO NEAR
NORMAL EARLY NEXT WEEK.
&&
.POINT TEMPS/POPS...
DLH 77 59 80 57 / 60 40 40 10
INL 81 60 79 57 / 70 50 40 20
BRD 84 63 83 60 / 40 20 10 10
HYR 80 60 83 58 / 50 40 40 20
ASX 77 56 80 57 / 60 50 30 30
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
AVIATION...CANNON
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
631 PM CDT THU JUN 27 2013
...MESOSCALE DISCUSSION AND UPDATE FOR AVIATION...
.MESOSCALE DISCUSSION...
ISSUED AT 630PM CDT THU JUN 27 2013
CONTINUING TO MONITOR CONVECTION EARLY THIS EVENING ACROSS CENTRAL
AND EAST CENTRAL KANSAS. SEVERE LINE OF STORMS HAS DEVELOPED NORTH
OF I-70 AS OF 615 PM...AND WILL CONTINUE TO RAPIDLY PUSH SOUTHEAST
THIS EVENING INTO SOUTHERN KANSAS AND NORTHERN OKLAHOMA. THIS
INITIAL AREA OF CONVECTION MAY CLIP A PORTION OF SOUTHEASTERN KANSAS
LATER THIS EVENING IN THE 8-10 PM TIMEFRAME...BUT IN ITS CURRENT
FORM...THE BULK OF THIS ACTIVITY WOULD STAY WEST OF THE SGF CWA.
THAT SAID...RECENT RADAR TRENDS ARE BEGINNING TO CONFIRM THE
SCENARIO DEPICTED BY SHORT TERM MODEL GUIDANCE...NAMELY RECENT RUNS
OF THE HRRR AND RUC/RAP...AS NEW CONVECTION IS BEGINNING TO DEVELOP
FURTHER NORTH AND EAST FROM TOPEKA TO KANSAS CITY. IF THIS
CONVECTION CAN CONTINUE TO GROW UPSCALE...IT SHOULD EVENTUALLY
CONGLOMERATE INTO A LINE OF STRONG TO SEVERE CONVECTION AS IT MOVES
SOUTHEAST INTO THE CWA. AT THIS TIME...IT APPEARS THAT THE BULK OF
THIS ACTIVITY WILL BE ALONG AND TO THE WEST OF U.S. 65 AS IT PASSES
THROUGH SOUTHERN MISSOURI.
THE MAIN SEVERE WEATHER CONCERN THIS EVENING WILL BE DAMAGING
STRAIGHT LINE WINDS. THE 00Z SGF SOUNDING DEPICTS EXTREME
INSTABILITY...WITH LOW LEVEL THETA-E DIFFERENTIALS IN THE
NEIGHBORHOOD OF 35-40K. THIS SUGGESTS A FAIRLY HIGH WIND POTENTIAL
WITH ANY STORMS...WITH GUSTS IN EXCESS OF 70 MPH POSSIBLE. MUCH OF
TONIGHT`S ACTIVITY WILL BE OUTFLOW DOMINATE IN NATURE...REDUCING THE
TORNADO THREAT TO VERY LOW LEVELS. SOME SEVERE HAIL WILL ALSO BE
POSSIBLE WITH SOME OF THE STRONGER CELLS...BUT THE HAIL THREAT
SHOULD DECREASE WITH TIME AS CONVECTION CONGEALS INTO A LINE.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 330 PM CDT THU JUN 27 2013
WARM AND HUMID CONDITIONS ARE OCCURRING ACROSS THE REGION THIS
AFTERNOON. TEMPERATURES ARE GENERALLY IN THE LOWER TO MIDDLE 90S
WITH HEAT INDEX VALUES IN THE 100 TO 109 RANGE...WITH THE HIGHEST
READINGS OCCURRING ALONG AND SOUTHWEST OF AN OSCEOLA TO
SPRINGFIELD TO ALTON MISSOURI LINE. THESE CONDITIONS WILL PERSIST
THROUGH THE REMINDER OF THE AFTERNOON HOURS INTO EARLY THIS
EVENING. WILL KEEP THE HEAT ADVISORY GOING AS IS UNTIL 8 PM FOR
THESE LOCATIONS.
AN OUTFLOW BOUNDARY THAT DEVELOPED WITH CONVECTION ACROSS NORTHERN
MISSOURI THIS MORNING IS CURRENTLY PUSHING SOUTH ACROSS THE AREA
THIS AFTERNOON. THE AREA REMAINS FAIRLY CAPPED DUE TO A WARM
AIRMASS...AND VERY LITTLE DEVELOPMENT HAS OCCURRED ON THIS
BOUNDARY. A FEW ISOLATED STORMS HAVE BEEN ABLE TO DEVELOP ACROSS
CENTRAL MISSOURI AND MAY REMAIN POSSIBLE ACROSS THE EASTERN
OZARKS THIS AFTERNOON AS THE OUTFLOW PUSHES SOUTH...THOUGH MOST
LOCATIONS SHOULD REMAIN DRY.
A SURFACE FRONT IS CURRENTLY LOCATED ACROSS NORTHERN AND WESTERN
KANSAS THIS AFTERNOON AND STORMS ARE BEGINNING TO DEVELOP ON THIS
BOUNDARY. THIS TREND WILL CONTINUE THIS AFTERNOON AND THESE STORMS
WILL FORM INTO A LINE LATER THIS AFTERNOON AND WILL ACCELERATE TO
THE SOUTHEAST TOWARDS THE AREA THIS EVENING...EXITING THE AREA
OVERNIGHT. LOCATIONS WITH THE BETTER POTENTIAL TO BE AFFECTED BY
THIS ACTIVITY WILL BE FARTHER TO THE WEST...GENERALLY ALONG AND
WEST OF HIGHWAY 65. THERE ARE MORE QUESTIONS HOW FAR EAST OF
HIGHWAY 65 THIS ACTIVITY CAN MAKE IT....THOUGH THUNDERSTORMS ARE
STILL POSSIBLE EAST OF HIGHWAY 65 THIS EVENING INTO THE OVERNIGHT
HOURS. THE FORCING ALONG THE FRONT/COLD POOL THAT DEVELOPS FROM
THE STORMS ACROSS KANSAS SHOULD BE ENOUGH TO BREAK THE CAP ACROSS
THE AREA AND WITH STRONG THETA-E DIFFERENCE AND A VERY UNSTABLE
AIRMASS WILL RESULT IN A STRONG DAMAGING WIND RISK WITH WINDS IN
EXCESS OF 70 TO 80 MPH LIKELY ALONG THIS LINE WITH THE BEST
POTENTIAL FOR WINDS THAT STRONG BEING WEST OF INTERSTATE 49. THERE IS
A HAIL RISK...BUT WITH THESE STORMS EXPECTED TO BE LINEAR IN
NATURE THIS POTENTIAL IS MORE LIMITED WITH GENERALLY UP TO
QUARTERS POSSIBLE. TIMING OF THIS AREA WILL GENERALLY BE BETWEEN 7
AND 10 PM ALONG AND WEST OF THE INTERSTATE 49 CORRIDOR AND BETWEEN
8 AND MIDNIGHT WEST OF HIGHWAY 65. THERE ARE MORE QUESTIONS IF
THIS LINE OF STORMS CAN MAKE IT EAST OF HIGHWAY 65...AND WILL HAVE
TO SEE EXACTLY WHERE THIS LINE SETS UP ACROSS KANSAS.
FRIDAY SHOULD GENERALLY BE DRY...THOUGH AN ISOLATED AFTERNOON
THUNDERSTORM MAY BE POSSIBLE IF ENOUGH INSTABILITY CAN DEVELOP...
THOUGH THIS POTENTIAL LOOKS REALLY LIMITED. TEMPERATURES WILL BE COOLER
ON FRIDAY THAN TODAY...BUT HIGHS WILL STILL TOP OUT IN THE UPPER 80S
TO THE LOWER 90S.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 330 PM CDT THU JUN 27 2013
AN UPPER LEVEL LOW WILL BUILD SOUTHWEST OUT OF THE GREAT LAKES
REGION OVER THE CENTRAL U.S. THIS WEEKEND THROUGH MUCH OF NEXT
WEEK. THIS WILL PUSH THE UPPER LEVEL RIDGE AND HOT AND MUGGY
CONDITIONS BACK TO THE WEST AND ALLOW A COOLER AIRMASS TO SPREAD INTO
THE REGION. HIGHS THIS WEEKEND THROUGH NEXT WEEK WILL GENERALLY BE IN
THE UPPER 70S TO THE MIDDLE 80S EACH AFTERNOON AS LOWS DROP INTO
THE LOWER TO MIDDLE 60S EACH NIGHT. THERE COULD BE PERIODS OF
SHOWERS AND THUNDERSTORMS AT TIMES AS THE UPPER LEVEL LOW REMAINS
OVER THE REGION BUT NO SEVERE WEATHER OR WASH OUT IS EXPECTED.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 630 PM CDT THU JUN 27 2013
STRONG/SEVERE CONVECTION CONTINUES TO FIRE ALONG A COLD FRONT TO
THE WEST AND NORTHWEST OF THE CWA. IF THIS LINE CAN FILL IN
BETWEEN SALINA AND KANSAS CITY...IT WILL LIKELY AFFECT THE TAF
SITES THIS EVENING BETWEEN 02Z AND 04Z. IF IT DOESNT FILL IN...THE
CURRENT CONVECTION TO THE WEST WILL LIKELY MISS OUR SITES TO THE
WEST. HAVE CURRENTLY PUT IN A TEMPO GROUP...ROUGHLY USING THE
LATEST HRRR AS TIMING GUIDANCE AFFECTING THE TAF SITES THIS
EVENING. PRIOR TO AND AFTER THE CONVECTION...VFR CONDITIONS
EXPECTED. DURING CONVECTION...GENERALLY MVFR CONDITIONS EXPECTED.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR MOZ066-067-077-078-
088>090-093>097-101>106.
KS...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR KSZ073-097-101.
&&
$$
MESOSCALE...BOXELL
SHORT TERM...WISE
LONG TERM...WISE
AVIATION...LINDENBERG
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
1256 AM CDT WED JUN 26 2013
.UPDATE...
ISSUED AT 1255 AM CDT WED JUN 26 2013
QUICK UPDATE TO THE FORECAST TO ACCOUNT FOR LATEST RADAR TRENDS.
AREA OF SHOWERS AND THUNDERSTORMS DEVELOPING ACROSS NORTH CENTRAL
MISSOURI WILL MOVE EAST/SOUTHEAST THE REMAINDER OF THE NIGHT
AFFECTING THE NORTHERN CWA.
ISSUED AT 953 PM CDT TUE JUN 25 2013
THUNDERSTORMS CONTINUE TO DEVELOP ACROSS IL JUST NE OF OUR
FORECAST AREA ALONG AN OLD OUTFLOW BOUNDARY. STILL EXPECTING
THUNDERSTORMS TO DEVELOP ACROSS IA AHEAD OF A WEAK SHORTWAVE AND
ON THE NOSE OF A SWLY LOW LEVEL JET...THEN GROW INTO AN MCS WHICH
SHOULD EVENTUALLY DROP SEWD INTO NERN MO AND W CNTRL IL LATE
TGT/EARLY WED MRNG. LOW TEMPERATURES TGT WILL BE QUITE MILD DUE TO
SOUTHERLY SFC WINDS AND HIGH SFC DEW POINTS.
GKS
&&
.SHORT TERM...(THROUGH LATE TONIGHT)
ISSUED AT 344 PM CDT TUE JUN 25 2013
SEVERAL THINGS TO DEAL WITH IN THE SHORT TERM TONIGHT. FIRST...STORMS
DEVELOPING IN WARM SECTOR AHEAD OF MCV THAT IS SLIDING EAST
THROUGH MO FROM MCS THAT WAS OVER WESTERN MO THIS MORNING...AS
WELL AS VARIOUS OLD OUTFLOW BOUNDARIES. THIS ACTIVITY SHOULD
DIMINISH MOST LOCATIONS BY EARLY THIS EVENING...THOUGH SOME
LINGERING ACTIVITY OVER NORTHEAST MO/WEST CENTRAL IL AS MCV SLIDES
EAST. THEN MODELS CONTINUE TO SHOW NEXT MCS DEVELOPING OVER IOWA.
FORECAST CORFIDI VECTORS HAVE THIS MCS SLIDE SOUTHEAST TOWARDS
FORECAST AREA...MAYBE EVEN MORE SOUTHERLY. SO SHOULD MOVE INTO
NORTHERN PORTIONS OF FORECAST AREA BY 06Z. LATEST HRRR RUN IS EVEN
FURTHER WEST WITH INITIAL DEVELOPMENT IN SOUTHERN IOWA...SO HAVE
RAISED POPS A BIT FURTHER WEST. THERE IS A SLIGHT RISK OF SEVERE
WEATHER...WITH THE MAIN THREATS BEING LARGE HAIL AND DAMAGING
WINDS. AS FOR TEMPS...TO REMAIN RATHER MILD WITH LOWS IN THE LOW
TO MID 70S OVERNIGHT.
BYRD
.LONG TERM...(WEDNESDAY THROUGH NEXT TUESDAY)
ISSUED AT 344 PM CDT TUE JUN 25 2013
COMPLEX SCENARIO ON TAP FOR WEDNESDAY WITH LOTS OF UNCERTAINTY TO
SPECIFIC FORECAST DETAILS. THE MAIN COMPLICATING FACTOR IS THE
OVERNIGHT MCS EXPECTED TO IMPACT WESTERN IL AND PORTIONS OF ERN MO
AND WHERE IT WILL BE LOCATED AT DAYBREAK. A CONSENSUS OF MODEL
SOLUTIONS HAVE THE DECAYING MCS IN CENTERED THRU IL AT DAYBREAK WITH
THE TRAILING FLANK OR BOUNDARY LOCATED ALONG THE MS RIVER IN ERN MO.
THE VEERED NATURE OF THE TROPOSPHERIC WINDS AND WLY LLJ WOULD
SUGGEST THIS SYSTEM SHOULD CONTINUE TO MOVE SEWD IN A DECAYING STATE
THROUGH THE MORNING WITH POTENTIAL FOR SOME STORMS ON THE TRAILING
BOUNDARY. STRONG HEATING SHOULD COMMENCE DURING THE DAY WITHIN THE
WARM SECTOR AHEAD OF THE ENCROACHING COLD FRONT...AS WELL AS WEST
OR SOUTHWEST OF ANY REMNANT BOUNDARIES. THE HEATING WILL BE MORE
LIMITED WITH EASTWARD EXTENT DUE TO RESIDUAL CLOUDINESS FROM THE
MORNING...BUT THE WARM SECTOR IS EXPECTED TO BECOME VERY UNSTABLE
AND WEAKLY CAPPED WITH SBCAPE AOA 4000 J/KG. SCATTERED THUNDERSTORMS
ARE EXPECTED TO REDEVELOP IN THE AFTERNOON WITHIN THE CONFLUENT ZONE
AHEAD OF THE COLD FRONT AND WITH ANY RESIDUAL BOUNDARIES...PRIMARILY
FROM EAST CENTRAL/SE MO INTO SOUTH CENTRAL AND SW IL. DEEP LAYER
SHEAR OF 30-40 KTS AND THE AMOUNT OF INSTABILITY WOULD FAVOR
SUPERCELL AND MULTICELL MODES. THE MORNING CONVECTION AND/OR
RESIDUAL CLOUDS PRESENT SOME PROBLEMS WITH RESPECT TO THE
MAGNITUDE OF HEAT. I HAVE COOLED TEMPS SLIGHTLY FROM ST LOUIS
EASTWARD AND THIS IS HIGHLY DEPENDENT ON MORNING CLOUDS. GIVEN THE
UNCERTAINTIES I HAVE DEFER ED ON ANY HEAT ADVISORIES WITH HEAT
INDICES FORECAST IN THE 100-105 RANGE. STORMS SHOULD BE CLOSE TO
EXITING THE CWA OR WILL HAVE EXITED THE CWA BY 00Z THURSDAY.
EVEN IN THE WAKE OF THE INITIAL COLD FRONT/BOUNDARY...THURSDAY LOOKS
LIKE ANOTHER SEASONABLY HOT DAY. IN FACT...IT IS NOT TOTALLY OUT OF
THE QUESTION IT COULD BE HOTTER THAN WEDNESDAY BUT WITH LESSER
HUMIDITY. THE ANTICIPATED NORTHWEST FLOW SHORTWAVE AND SECONDARY
COLD FRONT WILL MOVE THROUGH THE AREA LATE THURSDAY NIGHT INTO EARLY
FRIDAY WITH A PROMINENT WSW LLJ AHEAD OF IT. THIS SHOULD FUEL
ANOTHER MCS WHICH WILL IMPACT PORTIONS OF THE CWA. THE MODELS
DIVERGE ON THE MCS TRACK WITH THE GREATEST PROBABILITY ATTM
APPEARING TO BE THROUGH CENTRAL MO. MUCH COOLER AIR WILL THEN
SPREAD INTO THE AREA IN THE WAKE OF THE FRONT FOR FRIDAY AND SET
THE STAGE FOR A PROLONGED PERIOD OF BELOW AVERAGE TEMPERATURES
INTO THE EXTENDED RANGES.
THE EXTENDED RANGES WILL FEATURE AN AMPLIFIED BLOCKY UPPER AIR REGIME
FROM THE ERN PACIFIC ACROSS THE CONUS INTO THE WRN ATLANTIC...WITH A
STRONG UPPER HIGH/RIDGE CENTERED IN THE WRN U.S. AND DEEP TROF IN
THE ERN U.S. A SERIES OF SHORT WAVES WILL DROP SSEWD DOWN THE
BACKSIDE OF THE UPPER TROF AND IMPACT THE AREA ON SUNDAY AND TUESDAY
REINFORCING THE "COOLER" AIR AND BRINGING A CHANCE OF SHOWERS AND
THUNDERSTORMS.
GLASS
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1147 PM CDT TUE JUN 25 2013
THUNDERSTORMS HAVE BEGUN TO DEVELOP OVER NORTHWEST MISSOURI AND
HAVE SHOWN SOME EASTWARD MOVEMENT. CURRENT MOTION WOULD PLACE IT
AT KUIN AROUND 10Z. CURRENTLY EXPECT THESE STORMS TO STAY NORTH
OF KCOU...THOUGH WILL NEED TO MONITOR TO SEE IT DEVELOPMENT IS
FARTHER SOUTH THAN EXPECTED. THESE STORMS COULD ALSO AFFECT THE
ST. LOUIS METRO TAFS...WITH STORMS REMAINING IN THE AREA INTO
WEDNESDAY AFTERNOON. STORMS THROUGH SUNRISE COULD POSE A THREAT OF
GUSTY WINDS...SMALL HAIL AND MVFR/IFR CONDITIONS. STRONGER THREAT
FOR SEVERE THUNDERSTORMS WILL OCCUR ON WEDNESDAY AFTERNOON AS
STORMS REGENERATE MAINLY SOUTH AND EAST OF THE ST. LOUIS METRO
AREA.
SPECIFICS FOR KSTL...THERE CONTINUES TO BE A THREAT FOR
THUNDERSTORMS TOWARD SUNRISE THAT WILL CONTINUE INTO EARLY
AFTERNOON. TIMING IS STILL UNCERTAIN...SO WILL KEEP VCTS FOR NOW.
OTHERWISE EXPECT MAINLY DRY AND VFR CONDITIONS.
BRITT
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1206 AM CDT Wed Jun 26 2013
.UPDATE...
Issued at 1014 PM CDT TUE JUN 25 2013
Models continue to have difficulty grasping onto how convection will
unfold tonight. If 00z NAM and latest HRRR were on track we`d already
have an a convective complex forming over eastern NE and northeast
KS. However the latest radar and satellite data shows only a few
isolated cells over eastern NE. With the h7 shortwave axis, per SPC
analysis, now along the NE/IA state line trailing into central KS
focus for a convective complex is shifted eastward into central IA
where a considerable accas field is noted. HRRR and NAM both
eventually latch onto this area over the next few hours and spread
convection into northeast MO. Given the extensive accas field and
some new cells popping up over central IA will highlight northeast MO
with highest PoPs overnight.
&&
.SHORT TERM...(This Evening through Wednesday)
Issued at 405 PM CDT TUE JUN 25 2013
Convection across eastern Kansas, which kept our morning
temperatures rather pleasant thanks to the cloud cover, finally
dissipated in the early afternoon, allowing the sun to get to work
heating things up. As the cloud cover has moved off, readings have
begun jumping quickly towards the low 90s. The atmospheric
conditions that will prevail over the next couple of days will be
quite similar to today, only without the cooling effect from morning
convection.
Stormy activity later tonight is expected to get going in eastern
Nebraska and Iowa late tonight on the nose of a nocturnal jet.
Currently, expectations are that the hot and dry air that is
advecting in today -- 700mb temperatures > 13C -- will effectively
cap off much of eastern Kansas and western Missouri to any overnight
convection. Thoughts are that any activity in Iowa overnight will
likely put down a cold pool that could push some storms through north
central or northeast Missouri early Wednesday morning. However, this
activity is not expected to impact our temperatures
appreciably...though damaging winds and torrential rain will be
possible with these early morning storms.
Wednesday and into Thursday, the lack of cloud cover from storms
will allow temperatures to quickly bound into the 90s each day.
Light winds and dew point values in 60s to low 70s will result in
heat indices each day topping out around in the low 100s. In more
rural locations, this will be hot and humid but manageable, however
in the core of the Kansas City metropolitan area heat index values
will likely spike to around 105 degrees each day. As a result, in
consultation with the Kansas City MO Health Department, we are
opting to issue a heat advisory for the next two days. Currently,
the forecast for Friday indicates slightly cooler and drier
conditions, so at this time we are not expecting to need a heat
advisory beyond Thursday.
.LONG TERM...(Wednesday Night through Tuesday)
Issued at 405 PM CDT TUE JUN 25 2013
Backing 850 flow on Thursday will bring winds to the west and
southwest through the afternoon, potentially bringing temps at that
level even warmer than Weds with NAM and GFS showing 26C nudging
into western MO by afternoon. These temps would translate into
surface temps in the middle to upper 90s, while dewpoints remain
close to 70 degrees. This would yield heat indices across ern KS/wrn
MO in the 100-105 range, and being day 2 of such conditions could be
stressful especially for sensitive individuals in the KC core.
Amplifying upper ridge over the Rockies will strengthen the
northwest flow overhead on Thursday, allowing a front to drop
through the area Thursday night. This front will have an unstable
airmass to work with, but warm/dry air below 800 hPa may act against
widespread storms so kept PoPs limited to low chance category for
now.
Airmass behind the front will be relatively cooler with temperatures
returning into the lower/middle 80s by the weekend. An upper
shortwave trough will swing through the area on Sunday and could
spark a few showers or storms, but otherwise chances appear too low
to include a mention of precip through the remainder of the extended
period.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday Night)
Issued at 1205 AM CDT TUE JUN 25 2013
VFR conditions are expected through the entire forecast. Gusty south
winds will persist for a few more hours with winds shifting to the
southwest later tonight/early Wednesday morning. Winds will
eventually veer to the northwest by the afternoon as high pressure
moves over the region.
Thunderstorms have developed well northeast of the terminals and are
expected to move to the east/southeast through the night. Warm air
aloft over the terminals area will preclude any convective
development tonight. So the only areas that will see storms will be
across northern into northeastern Missouri, impacting mainly
the Kirksville and Chillicothe airspace.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...HEAT ADVISORY from 11 AM Wednesday to 7 PM CDT Thursday FOR
KSZ103>105.
MO...HEAT ADVISORY from 11 AM Wednesday to 7 PM CDT Thursday FOR
MOZ028-029-037.
&&
$$
UPDATE...MJ
SHORT TERM...Cutter
LONG TERM...Hawblitzel
AVIATION...CDB
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1154 PM CDT TUE JUN 25 2013
.UPDATE...
ISSUED AT 953 PM CDT TUE JUN 25 2013
THUNDERSTORMS CONTINUE TO DEVELOP ACROSS IL JUST NE OF OUR
FORECAST AREA ALONG AN OLD OUTFLOW BOUNDARY. STILL EXPECTING
THUNDERSTORMS TO DEVELOP ACROSS IA AHEAD OF A WEAK SHORTWAVE AND
ON THE NOSE OF A SWLY LOW LEVEL JET...THEN GROW INTO AN MCS WHICH
SHOULD EVENTUALLY DROP SEWD INTO NERN MO AND W CNTRL IL LATE
TGT/EARLY WED MRNG. LOW TEMPERATURES TGT WILL BE QUITE MILD DUE TO
SOUTHERLY SFC WINDS AND HIGH SFC DEW POINTS.
GKS
&&
.SHORT TERM...(THROUGH LATE TONIGHT)
ISSUED AT 344 PM CDT TUE JUN 25 2013
SEVERAL THINGS TO DEAL WITH IN THE SHORT TERM TONIGHT. FIRST...STORMS
DEVELOPING IN WARM SECTOR AHEAD OF MCV THAT IS SLIDING EAST
THROUGH MO FROM MCS THAT WAS OVER WESTERN MO THIS MORNING...AS
WELL AS VARIOUS OLD OUTFLOW BOUNDARIES. THIS ACTIVITY SHOULD
DIMINISH MOST LOCATIONS BY EARLY THIS EVENING...THOUGH SOME
LINGERING ACTIVITY OVER NORTHEAST MO/WEST CENTRAL IL AS MCV SLIDES
EAST. THEN MODELS CONTINUE TO SHOW NEXT MCS DEVELOPING OVER IOWA.
FORECAST CORFIDI VECTORS HAVE THIS MCS SLIDE SOUTHEAST TOWARDS
FORECAST AREA...MAYBE EVEN MORE SOUTHERLY. SO SHOULD MOVE INTO
NORTHERN PORTIONS OF FORECAST AREA BY 06Z. LATEST HRRR RUN IS EVEN
FURTHER WEST WITH INITIAL DEVELOPMENT IN SOUTHERN IOWA...SO HAVE
RAISED POPS A BIT FURTHER WEST. THERE IS A SLIGHT RISK OF SEVERE
WEATHER...WITH THE MAIN THREATS BEING LARGE HAIL AND DAMAGING
WINDS. AS FOR TEMPS...TO REMAIN RATHER MILD WITH LOWS IN THE LOW
TO MID 70S OVERNIGHT.
BYRD
.LONG TERM...(WEDNESDAY THROUGH NEXT TUESDAY)
ISSUED AT 344 PM CDT TUE JUN 25 2013
COMPLEX SCENARIO ON TAP FOR WEDNESDAY WITH LOTS OF UNCERTAINTY TO
SPECIFIC FORECAST DETAILS. THE MAIN COMPLICATING FACTOR IS THE
OVERNIGHT MCS EXPECTED TO IMPACT WESTERN IL AND PORTIONS OF ERN MO
AND WHERE IT WILL BE LOCATED AT DAYBREAK. A CONSENSUS OF MODEL
SOLUTIONS HAVE THE DECAYING MCS IN CENTERED THRU IL AT DAYBREAK WITH
THE TRAILING FLANK OR BOUNDARY LOCATED ALONG THE MS RIVER IN ERN MO.
THE VEERED NATURE OF THE TROPOSPHERIC WINDS AND WLY LLJ WOULD
SUGGEST THIS SYSTEM SHOULD CONTINUE TO MOVE SEWD IN A DECAYING STATE
THROUGH THE MORNING WITH POTENTIAL FOR SOME STORMS ON THE TRAILING
BOUNDARY. STRONG HEATING SHOULD COMMENCE DURING THE DAY WITHIN THE
WARM SECTOR AHEAD OF THE ENCROACHING COLD FRONT...AS WELL AS WEST
OR SOUTHWEST OF ANY REMNANT BOUNDARIES. THE HEATING WILL BE MORE
LIMITED WITH EASTWARD EXTENT DUE TO RESIDUAL CLOUDINESS FROM THE
MORNING...BUT THE WARM SECTOR IS EXPECTED TO BECOME VERY UNSTABLE
AND WEAKLY CAPPED WITH SBCAPE AOA 4000 J/KG. SCATTERED THUNDERSTORMS
ARE EXPECTED TO REDEVELOP IN THE AFTERNOON WITHIN THE CONFLUENT ZONE
AHEAD OF THE COLD FRONT AND WITH ANY RESIDUAL BOUNDARIES...PRIMARILY
FROM EAST CENTRAL/SE MO INTO SOUTH CENTRAL AND SW IL. DEEP LAYER
SHEAR OF 30-40 KTS AND THE AMOUNT OF INSTABILITY WOULD FAVOR
SUPERCELL AND MULTICELL MODES. THE MORNING CONVECTION AND/OR
RESIDUAL CLOUDS PRESENT SOME PROBLEMS WITH RESPECT TO THE
MAGNITUDE OF HEAT. I HAVE COOLED TEMPS SLIGHTLY FROM ST LOUIS
EASTWARD AND THIS IS HIGHLY DEPENDENT ON MORNING CLOUDS. GIVEN THE
UNCERTAINTIES I HAVE DEFER ED ON ANY HEAT ADVISORIES WITH HEAT
INDICES FORECAST IN THE 100-105 RANGE. STORMS SHOULD BE CLOSE TO
EXITING THE CWA OR WILL HAVE EXITED THE CWA BY 00Z THURSDAY.
EVEN IN THE WAKE OF THE INITIAL COLD FRONT/BOUNDARY...THURSDAY LOOKS
LIKE ANOTHER SEASONABLY HOT DAY. IN FACT...IT IS NOT TOTALLY OUT OF
THE QUESTION IT COULD BE HOTTER THAN WEDNESDAY BUT WITH LESSER
HUMIDITY. THE ANTICIPATED NORTHWEST FLOW SHORTWAVE AND SECONDARY
COLD FRONT WILL MOVE THROUGH THE AREA LATE THURSDAY NIGHT INTO EARLY
FRIDAY WITH A PROMINENT WSW LLJ AHEAD OF IT. THIS SHOULD FUEL
ANOTHER MCS WHICH WILL IMPACT PORTIONS OF THE CWA. THE MODELS
DIVERGE ON THE MCS TRACK WITH THE GREATEST PROBABILITY ATTM
APPEARING TO BE THROUGH CENTRAL MO. MUCH COOLER AIR WILL THEN
SPREAD INTO THE AREA IN THE WAKE OF THE FRONT FOR FRIDAY AND SET
THE STAGE FOR A PROLONGED PERIOD OF BELOW AVERAGE TEMPERATURES
INTO THE EXTENDED RANGES.
THE EXTENDED RANGES WILL FEATURE AN AMPLIFIED BLOCKY UPPER AIR REGIME
FROM THE ERN PACIFIC ACROSS THE CONUS INTO THE WRN ATLANTIC...WITH A
STRONG UPPER HIGH/RIDGE CENTERED IN THE WRN U.S. AND DEEP TROF IN
THE ERN U.S. A SERIES OF SHORT WAVES WILL DROP SSEWD DOWN THE
BACKSIDE OF THE UPPER TROF AND IMPACT THE AREA ON SUNDAY AND TUESDAY
REINFORCING THE "COOLER" AIR AND BRINGING A CHANCE OF SHOWERS AND
THUNDERSTORMS.
GLASS
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1147 PM CDT TUE JUN 25 2013
THUNDERSTORMS HAVE BEGUN TO DEVELOP OVER NORTHWEST MISSOURI AND
HAVE SHOWN SOME EASTWARD MOVEMENT. CURRENT MOTION WOULD PLACE IT
AT KUIN AROUND 10Z. CURRENTLY EXPECT THESE STORMS TO STAY NORTH
OF KCOU...THOUGH WILL NEED TO MONITOR TO SEE IT DEVELOPMENT IS
FARTHER SOUTH THAN EXPECTED. THESE STORMS COULD ALSO AFFECT THE
ST. LOUIS METRO TAFS...WITH STORMS REMAINING IN THE AREA INTO
WEDNESDAY AFTERNOON. STORMS THROUGH SUNRISE COULD POSE A THREAT OF
GUSTY WINDS...SMALL HAIL AND MVFR/IFR CONDITIONS. STRONGER THREAT
FOR SEVERE THUNDERSTORMS WILL OCCUR ON WEDNESDAY AFTERNOON AS
STORMS REGENERATE MAINLY SOUTH AND EAST OF THE ST. LOUIS METRO
AREA.
SPECIFICS FOR KSTL...THERE CONTINUES TO BE A THREAT FOR
THUNDERSTORMS TOWARD SUNRISE THAT WILL CONTINUE INTO EARLY
AFTERNOON. TIMING IS STILL UNCERTAIN...SO WILL KEEP VCTS FOR NOW.
OTHERWISE EXPECT MAINLY DRY AND VFR CONDITIONS.
BRITT
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
157 AM EDT WED JUN 26 2013
.SYNOPSIS...
WEAK DISTURBANCES WILL CROSS THE AREA THROUGH WEDNESDAY...WITH
SCATTERED SHOWERS OR THUNDERSTORMS ANTICIPATED...BUT ALSO
SIGNIFICANT PERIODS OF RAIN-FREE WEATHER. BY THURSDAY...A STRONGER
SYSTEM WILL APPROACH...AND IS EXPECTED TO BRING MORE PERSISTENT
SHOWERS AND THUNDERSTORMS. MUGGY AND SEASONABLY WARM CONDITIONS
WILL CONTINUE...WITH HIGHS MOSTLY IN THE 80S THROUGH THE END OF
THE WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
10 UPDATE...CONV CONTS TO FIRE ACROSS CNTRL PA AHD OF A PARADE OF
WEAK SHRT WVS IN THE WLY FLOW. HRRR SEMS TO HAVE THE BEST HANDLE
ON THE CONV AND CONTS THE PCPN...WITH SLOW WEAKENING OVRNGT. WILL
CONT WITH CHANCE POPS OVER THE SRN ZONES AND SLGT CHANCE ELSEWHERE
FOR ROGUE SHWRS FIRING FURTHER NORTH. PLENTY OF CLDS UPSTREAM AS
WELL SO FOG SHD NOT BE A BIG CNCRN OVERNGT. PRVS DISC BLO.
345 PM UPDATE... ONE BATCH OF CONVECTION IS EXITING OUR ERN ZNS
LATE THIS AFTN...ASSOCD WITH A DEPARTING MCV. CNY/NE PA SHOULD
EXPERIENCE A RELATIVE LULL/RAIN-FREE PD THROUGH 22-00Z.
BY EARLY EVE...AN ORGANIZING BAND OF SHRA/TSRA...FROM SRN ONT ACRS
LK ERIE AND ERN OH ATTM...IS EXPECTED TO COME EWD...AND COULD WELL
IMPACT SRN PTNS OF THE FA. THERE IS SOME UNCERTAINTY REGARDING LINGERING
AMTS OF INSTAB BY THIS TIME...BUT IT WILL LIKELY STILL BE
UNSTABLE ENOUGH FOR AT LEAST SCTD COVERAGE. GIVEN INCREASED VERT
SHEAR THIS EVE (0-3 KM VALUES NEAR 40 KT)...STORMS WILL HAVE TO BE
WATCHED FOR WIND POTENTIAL...SHOULD THEY ORGANIZE INTO LINEAR
FEATURES.
LTR TNT...WE SHOULD SEE A SHORT BREAK IN PCPN ONCE AGN. SINCE
THERE IS PLENTY OF CLOUD DEBRIS UPSTREAM TO THE W ATTM...WE
ANTICIPATE PTLY TO MOSTLY CLDY SKIES MUCH OF THE NGT...AND THIS
CLOUD COVER SHOULD CUT DOWN ON THE RADIATIONAL COOLING/FOG
POTENTIAL.
TWDS DAYBREAK...ANOTHER INCOMING UPR-LVL WAVE COULD BRING A ROUND
OF SHWRS...AND WE`VE THUS BROUGHT CHC/SCTD POPS IN FROM THE W
AFTER 08-09Z.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
4 PM UPDATE... AN UPR-LVL WAVE WILL CROSS NY/PA WED...MAINLY IN
THE AM HRS (BEFORE 18Z). SUCH EARLY TIMING WOULD SUGGEST NON-SVR
STORMS...WITH PERHAPS INSUFFICIENT TIME FOR ADEQUATE
DESTABILIZATION...BEFORE THE WV BEGINS TO DEPART...WITH
DIMINISHING ACTIVITY IN THE AFTN. FOR NOW...WE GRADUALLY TAPER
CHC/SCTD POPS BACK...FROM NW TO SE...AFTER 18Z.
THE NEXT STGR UPR-LVL SYSTEM IS PROGGED TO DIG INTO THE ERN LKS/OH
VLY RGN LATE WED NGT/THU. AT THIS EARLY JUNCTURE...MOST OF WED NGT
SHOULD FEATURE EITHER NO PCPN...OR JUST HIT AND MISS SHWR ACTIVITY.
HOWEVER...LATE AT NGT INTO THU AM...OUR CHCS FOR SHWRS/THUNDER
SHOULD INCREASE...AS UPR-LVL JET FORCING AND MOISTURE ADVECTION
IMPROVE.
THERE REMAIN SUBTLE MODEL POSITIONING DIFFS ON THU...BUT THE
MAIN SYNOPTIC IDEA IS FOR A FAIRLY AMPLIFIED UPR-LVL WAVE TO
SLOWLY LIFT FROM THE OH VLY INTO THE NERN STATES...WITH A PRETTY
WELL DEFINED SFC LOW FOR THIS TIME OF YEAR...TRANSLATING NEWD
ACRS PA AND NY STATE. THUS...WE`VE BUMPED POPS INTO THE LIKELY/NUMEROUS
RANGES. DEPENDING ON SPECIFICALLY WHERE THE SFC LOW TRACKS...THE
WARM SECTOR DVLPS...AND THE EXTENT OF CLOUD COVER/SFC
HEATING...THERE IS POTENTIAL FOR SVR STORMS (GOOD LOW-LVL DIR
SHEAR AND VERT SPEED SHEAR). WE`LL SIMPLY HAVE TO SEE HOW THINGS
EVOLVE OVER THE NEXT COUPLE OF DAYS. FOR NOW...WE`LL CONTINUE TO
HIGHLIGHT THIS POTENTIAL IN THE HWO.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
VERY FEW CHANGES MADE TO THE EXTENDED TIME FRAME WITH THE
EXCEPTION OF INCREASING POPS INTO THE LIKELY CATEGORY THIS WEEKEND
INTO EARLY NEXT WEEK AS MODEL TRENDS CONTINUE TO FAVOR A VERY WET
SCENARIO IN COMING DAYS. MAIN CULPRITS CONTINUE TO BE DEVELOPING
RIDGING ACROSS BOTH THE NORTHERN ATLANTIC AND INTERMOUNTAIN
WEST...WITH ALL MODELS ALSO SHOWING A DIGGING UPPER-LEVEL TROUGH
EXTENDING FROM THE CENTRAL GREAT LAKES SOUTH INTO THE LWR MISS RVR
VLY. CONCERNS CONTINUE TO INCREASE THAT TROPICAL CONNECTIONS WILL
BECOME FIRMLY ESTABLISHED BY THE WEEKEND AS THE GULF OF MEXICO AND
WESTERN ATLANTIC REMAIN WIDE-OPEN FOR STRONG LOW-LEVEL MOISTURE
TRANSPORT NORTH ALONG THE ATLANTIC SEABOARD. AS A RESULT...FELT
COMPELLED TO INCREASE POPS ACCORDINGLY...WHICH AGREES WELL WITH
LATEST 12Z WPC GUIDANCE. TRENDS WILL HAVE TO BE MONITORED IN
COMING DAYS...BUT THE DEVELOPING SYNOPTIC PATTERN LOOKS EERILY
SIMILAR TO PATTERNS RESPONSIBLE FOR PAST LARGE-SCALE EAST COAST
FLOOD EVENTS. STAY TUNED!
&&
.AVIATION /06Z WEDNESDAY THROUGH THURSDAY NIGHT/...
200 AM EDT UPDATE...
A FEW ISOLATED SHOWERS ARE LINGERING ACROSS CENTRAL NY EARLY
THIS MORNING. THIS ACTIVITY WILL SLOWLY DIMINISH OVER THE NEXT FEW
HOURS. LOW LEVEL MOISTURE WILL CREEP INTO CENTRAL NY THIS MORNING
FROM THE WEST AND WITH THE SHOWERS DIMINISHING... A LOW STRATUS
DECK NEAR 2500 FT MAY FORM ACROSS THE REGION AND LAST FOR A FEW
HOURS. ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS
THE AREA WEDNESDAY MORNING/AFTERNOON. THIS ACTIVITY WILL DISRUPT
THE STRATUS DECK AND VFR CONDITIONS WILL RETURN WITH MVFR
VISIBILITIES. THIS ROUND OF STORMS WILL PUSH THROUGH THE REGION BY
LATE AFTERNOON AND VFR CLOUD DECKS WILL LINGER IN THE PASSING OF THE
SYSTEM.
OUTLOOK...FRI THROUGH SUN...
FRI...MAINLY VFR. EARLY MORNING MVFR/IFR IN VALLEY FOG.
SAT...MVFR RESTRICTIONS POSSIBLE IN DEVELOPING RA.
SUN...MVFR POSSIBLE IN SHOWERS/STORMS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DGM/MLJ
NEAR TERM...DGM/MLJ
SHORT TERM...MLJ
LONG TERM...CMG
AVIATION...KAH
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1017 PM EDT THU JUN 27 2013
.SYNOPSIS...
UNSETTLED WEATHER WILL CONTINUE THROUGH THE MIDDLE OF NEXT WEEK WITH
A DAILY RISK OF SHOWERS AND THUNDERSTORMS. SIGNIFICANT RAINFALL
AMOUNTS ARE EXPECTED THROUGH THE PERIOD AND THIS RAIN WILL BE
FALLING ON ALREADY WET SOILS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 PM THURSDAY...THE LAST IN THE SERIES OF SHORTWAVE
DISTURBANCES ALOFT WILL PUSH ACROSS THE EASTERN CAROLINAS IN THE
NEXT SEVERAL HOURS...LIKELY SUSTAINING CONVECTION ACROSS THE AREA
THROUGH MIDNIGHT AND PERHAPS BEYOND. WITH SUCH A HUMID AIRMASS
(PRECIPITABLE WATER 2.0 TO 2.1 INCHES AND SURFACE DEWPOINTS IN THE
70S) VIRTUALLY ANY STORM CELL IS PRODUCING RAINFALL RATES IN EXCESS
OF 1 INCH PER HOUR. BASED MAINLY ON CURRENTLY OBSERVED RADAR TRENDS
I HAVE ADJUSTED POPS UP FOR THE NEXT 3-4 HOURS TO 100 PERCENT FROM
EASTERN COLUMBUS COUNTY THROUGH THE WILMINGTON METRO AREA...AND JUST
SOUTH OF FLORENCE TO NEAR KINGSTREE. THIS ACTIVITY IS PROBABLY NO
LONGER SURFACE BASED BUT IS TAKING ADVANTAGE OF A STRENGTHENING LOW
LEVEL JET WHICH IS ADVECTING IN EXTREMELY HUMID AIR OFF THE ATLANTIC
WITH DEWPOINTS IN THE UPPER 70S. FLOOD ADVISORIES OR WARNINGS MAY
NEED TO BE ISSUED IN THE NEXT HOUR OR TWO GIVEN THE SLOW OBSERVED
CELL MOTION COUPLED WITH HIGH RAINFALL RATES. PREVIOUS DISCUSSION
FROM 730 PM FOLLOWS...
A SERIES OF TWO UPPER LEVEL DISTURBANCES
ROLLING ACROSS A STRONGLY UNSTABLE AIRMASS LED TO THE DEVELOPMENT OF
WIDESPREAD THUNDERSTORMS THIS AFTERNOON. SURFACE-BASED INSTABILITY
IS NOW WANING WITH THE LOSS OF INSOLATION AND THE LARGE-SCALE
OVERTURNING OF THE AIRMASS. HOWEVER CONSIDERABLE INSTABILITY (CAPE:
3000 J/KG) REMAINS SOUTH AND WEST OF FLORENCE WITH LESSER
INSTABILITY ALONG THE COAST FROM MYRTLE BEACH THROUGH WILMINGTON. (A
SMALL NEGATIVE REGION OF CONVECTIVE INHIBITION ALONG THE COAST COULD
PREVENT THIS INSTABILITY FROM BEING REALIZED)
SYNOPTIC MODELS ARE OFTEN OF LITTLE USE IN FORECASTING CONVECTION.
THE HRRR HIGH-RESOLUTION MODEL IS HAVING TROUBLE INITIALIZING THE
STORM PROPERLY BUT THE LAST SEVERAL RUNS SUGGEST THE INSTABILITY
SOUTH OF FLORENCE TOWARD THE SANTEE RIVER INTO THE CHARLESTON METRO
AREA WILL BE THE BREEDING GROUND FOR ANOTHER CLUSTER OF CONVECTION
OVER THE NEXT SEVERAL HOURS. THE FINAL UPPER LEVEL SHORTWAVE MOVING
SOUTHEAST THROUGH THE PIEDMONT REGION COULD ALSO IGNITE NEW STORMS
ACROSS THE SANDHILLS IN THE NEXT FEW HOURS WITH THE INTERSTATE 95
CORRIDOR POTENTIALLY RECEIVING ANOTHER ROUND OF ACTIVITY.
IN TERMS OF FORECAST POPS...I HAVE THE HIGHEST POPS FOR THE NEXT FEW
HOURS ACROSS NORTHERN ROBESON INTO BLADEN COUNTIES IN NC. BY LATE
THIS EVENING I SHIFT THE BULLSEYE SOUTHWARD FROM JUST INLAND OF
GEORGETOWN ACROSS CENTRAL HORRY COUNTY TO NEAR WILMINGTON. (50-60
PERCENT) AFTER MIDNIGHT MOST OF THE CONVECTIVE ACTIVITY SHOULD SHIFT
OFFSHORE BEHIND THE FINAL SHORTWAVE ALOFT...WITH DRYING CONDITIONS
TEMPORARILY BUILDING IN FROM THE WEST. I SAY TEMPORARILY BECAUSE THE
PATTERN FOR TOMORROW AFTERNOON THROUGH THE WEEKEND IS WET TO SAY THE
LEAST!
FORECAST LOWS TONIGHT RANGE FROM 72-77...COOLEST WEST OF I-95 AND
WARMEST ALONG THE COAST.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 PM THURSDAY...A BROAD UPPER LOW ACROSS THE GREAT LAKES WILL
SLOWLY RELOCATE ACROSS THE OHIO VALLEY DURING THIS PERIOD. MID-LEVEL
SHORTWAVE ENERGY ROTATING AROUND THE UPPER LOW WILL HELP TO ENHANCE
SHOWERS AND THUNDERSTORMS. SURFACE FEATURES THAT WILL HELP TO
CONVERGE AND LIFT A MOIST AND UNSTABLE AIRMASS INCLUDE THE SEABREEZE
AND THE PIEDMONT TROUGH. OVERALL...A WET PERIOD IS IN STORE WITH
BOUTS OF SHOWERS AND THUNDERSTORMS. RAINFALL AMOUNTS JUST DURING
THIS PERIOD WILL LIKELY ADD ANOTHER 1 TO 2 INCHES TO WHAT HAS BEEN A
VERY WET JUNE ALREADY. AS IS USUALLY THE CASE WITH CONVECTION...SOME
SPOTS COULD RECEIVE AMOUNTS CONSIDERABLY HIGHER THAN THIS RANGE.
IT LOOKS AS THOUGH ONE SUCH SHORTWAVE WILL LIFT OUT ACROSS THE
EASTERN CAROLINAS DURING FRI AFTERNOON. MIXED LAYER CAPE VALUES ARE
VERY HIGH ON FRI...REACHING 3000 J/KG. MID-LEVEL LAPSE RATES ARE
HOWEVER MODEST. THE FLOW IS LARGELY WESTERLY...EXCEPT SW IN THE
LOWEST 3-5 KFT OR SO. THERE IS CONSIDERABLE DRY AIR IN THE
MID-LEVELS FRI MORNING...BUT THEN OVERTIME...THE COLUMN MOISTENS
FROM W TO E...DURING THE AFTERNOON AND EVE. THUS...THE SCENARIO
PAINTED BY SEVERAL OF THE MODELS LOOKS REASONABLE...SHOWERS AND
THUNDERSTORMS DEVELOPING ALONG THE PIEDMONT TROUGH IN RESPONSE TO
STRONG HEATING AND MOVING ACROSS OUR WESTERN ZONES FRI AFTERNOON AND
THEN TO THE COAST FRI EVE/NIGHT. A FEW STORMS MAY ALSO POP ALONG THE
SEABREEZE FRI AFTERNOON. GIVEN THE MAGNITUDE OF INSTABILITY AND
DEVELOPING INVERTED V SOUNDINGS...THERE IS A RISK FOR STRONG TO
POSSIBLY DAMAGING WINDS IN THE DEEPEST CONVECTION. MID-LEVEL TEMPS
SHOULD BE COOL ENOUGH TO SUPPORT HAIL IN ANY STRONG AND PERSISTENT
UPDRAFTS. THIS IS IN ADDITION TO THE HEAVY RAIN AND FREQUENT DEADLY
LIGHTING RISK. THE CONVECTION SHOULD ONLY SLOWLY WANE WITH LOSS OF
HEATING THROUGH THE LATE EVE AND OVERNIGHT.
SAT...THE FLOW TURNS MORE SOUTHWESTERLY THROUGH A DEEP LAYER AND
THERE IS NO DRY AIR IN THE COLUMN TO BE FOUND. THE COLUMN IS
SATURATED OR NEARLY SO THROUGH A DEEP LAYER. SOME OF THE MODELS ARE
INDICATING A SHORTWAVE TROUGH MOVING UP THE COAST...BUT A GOOD
DISTANCE OFFSHORE. WE WILL HAVE TO WATCH THIS FEATURE TO SEE HOW IT
EVENTUALLY PLAYS OUT. THERE MAY BE SOME SUBSIDENCE DEVELOPING ON THE
BACK SIDE WHICH WOULD TEND TO SUPPRESS/REDUCE CONVECTION.
HOWEVER...CLOSER TO THE COAST AND THERE COULD BE CONSIDERABLE
CONVECTION AT AND NEAR THE COAST. GIVEN THE ENVIRONMENT...IT WILL
TAKE VERY LITTLE TO IGNITE CONVECTION. STORM MOTIONS SHOULD BE MUCH
QUICKER ON SAT THAN ON FRI AS THE WIND FIELDS WILL BE STRONGER. WET
MICROBURSTS CAN NOT BE RULED OUT ON SAT.
CLOUD COVER SHOULD BE MORE WIDESPREAD SAT THAN ON FRI GIVEN THE
EXPECTED MOISTURE PROFILES. WILL THUS FORECAST HIGHER TEMPS ON
FRI...LOWER TO MID 90S. THE SEABREEZE SHOULD BE PINNED NEAR THE
COAST AND SO EVEN THE BEACHES SHOULD REACH THE UPPER 80S WITH THE
EXCEPTION OF BRUNSWICK AND SOUTHERN NEW HANOVER COUNTIES WHERE A
MORE ONSHORE FLOW SHOULD KEEP AFTERNOON TEMPS IN THE MID 80S. HIGHS
ON SAT WILL BE MAINLY IN THE UPPER 80S TO AROUND 90 WELL INLAND WITH
MID 80S AT THE BEACHES AS THE SEABREEZE SHOULD BE ABLE TO MAKE A
LITTLE FURTHER PROGRESS INLAND. LOWS WILL BE IN THE MUGGY 70S.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 3 PM THURSDAY...ACTIVE WEATHER WILL CONTINUE THROUGH AT
LEAST THE FIRST HALF OF THE WEEK. MID TO UPPER TROUGH DIGGING DOWN
THROUGH THE MISSISSIPPI VALLEY ON SUNDAY WILL LIFT TOWARD THE
NORTHWEST AS STRONG UPPER RIDGE TO OUR EAST TRIES TO BUILD
WESTWARD ACROSS THE EAST COAST. INITIALLY LOCAL AREA WILL REMAIN
BETWEEN THESE TWO FEATURES ON THE ACTIVE SIDE OF MID TO UPPER
TROUGH. SHORTWAVE ENERGY WILL ROTATE AROUND THE TROUGH UP THROUGH
THE CAROLINAS ENHANCING LOCALIZED CONVECTION SUNDAY THROUGH MID
WEEK. THE CONVECTION SHOULD FIRST FIRE UP OVER THE SEA BREEZE
CONVERGENT BOUNDARY AND THE PIEDMONT TROUGH INLAND BUT THEN WILL
BECOME MORE WIDESPREAD ALONG MESO OUTFLOW BOUNDARIES. OVERALL WILL
REMAIN IN DEEP MOIST SOUTHERLY FLOW AND EXPECT PLENTY OF CLOUDS
AND CONVECTION EACH DAY IN A WARM AND HUMID SUMMERTIME AIR MASS.
THE STEERING FLOW WILL KEEP STORMS MOVING FROM SOUTH TO NORTH AND
MAY ALLOW FOR BETTER WEATHER ALONG THE IMMEDIATE COAST.
AS MID TO UPPER TROUGH LIFTS FARTHER NORTH INTO CANADA THE RIDGE MAY
MAKE IT FAR ENOUGH WEST TO PROVIDE SOME SUBSIDENCE AND DRYING
THROUGH THE MID LEVELS OF THE ATMOSPHERE BY WED OR THURS. WITHOUT
THE UPPER LEVEL SUPPORT WE CAN GET BACK TO LESS IN THE WAY OF
STRONGER CONVECTION AND JUST LOCALIZED SHOWER ACTIVITY ALONG THE SEA
BREEZE AND PIEDMONT TROUGH.
TEMPS WILL RUN NEAR OR ABOVE NORMAL THROUGH THE PERIOD WITH 70S FOR
OVERNIGHT LOWS AND CLOSE TO 90 FOR AFTERNOON HIGHS.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
AS OF 00Z...SEVERAL BANDS OF SHOWERS AND THUNDERSTORMS CONTINUE
ACROSS THE TERMINAL AREA THIS EVENING. WITH STRONG INSTABILITY AND
A MOIST AIRMASS THUNDERSTORMS WILL REMAIN POSSIBLE THROUGH 03Z AT
KFLO/KLBT AND THROUGH 06Z AT THE COASTAL TERMINALS. VFR IS EXPECTED
OUTSIDE OF PRECIPITATION. SINCE PRECIPITATION IS MOVING RATHER
QUICKLY FEEL TEMPO MVFR CONDITIONS WILL BE MOST LIKELY WITH THIS
ACTIVITY...BUT BRIEF IFR/LIFR COULD CERTAINLY OCCUR AS WELL AS
VARIABLE WIND GUSTS TO 30 KTS IF A CELL MOVES DIRECTLY OVER ANY
TERMINAL. PER RADAR LOOPS KLBT/KFLO WILL HAVE THE BEST CHANCE OF
THUNDERSTORMS THROUGH 02Z-03Z WITH LOWER CONFIDENCE OF OCCURRENCE AT
KFLO.
AFTER 06Z EXPECT ONLY ISOLATED SHOWERS...AND THAT MOST LIKELY AT THE
COASTAL TERMINALS THROUGH SUNRISE. VFR EXPECTED AT THE COASTAL
TERMINALS THROUGH SUNRISE BUT THERE IS MODERATE CONFIDENCE IFR
CIGS/MVFR VSBYS COULD AGAIN DEVELOP AT KFLO/KLBT 08-12Z. EXPECT THE
SAME PATTERN OF CONVECTIVE ACTIVITY FOR FRIDAY WITH GENERALLY VFR
CONDITIONS...SHOWERS AND ISOLATED THUNDERSTORMS ALONG THE SEA BREEZE
DURING THE MORNING AND NEAR KFLO/KLBT DURING THE AFTERNOON.
EXTENDED OUTLOOK...ISOLATED/SCATTERED AFTERNOON SHOWERS AND
THUNDERSTORMS THROUGH TUESDAY WITH BRIEF LOCALIZED PERIODS OF
MVFR/IFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 PM THURSDAY...NEW THUNDERSTORMS ARE MOVING OFF THE COAST
NORTH OF CAPE FEAR. THESE STORMS MAY BE FOLLOWED BY MORE WAVES OF
STORMS OVERNIGHT AS ANOTHER UPPER LEVEL DISTURBANCE PUSHES OFF THE
COAST. THE UPDATED FORECAST FEATURES INCREASED THUNDERSTORM
POTENTIAL THROUGH ABOUT 2-3 AM FRIDAY...WITH LESSENING CHANCES LATE
TONIGHT. ALTHOUGH SYNOPTIC-SCALE WINDS WILL REMAIN FROM THE
SOUTHWEST AT 15-25 KNOTS...OBVIOUSLY THUNDERSTORM-SCALE WINDS MUCH
TOO SMALL TO FORECAST MORE THAN 1-2 HOURS IN ADVANCE WILL DOMINATE
THE WEATHER THROUGH THE NIGHT. MARINERS SHOULD CLOSELY WATCH FOR
THESE STORMS AS THEY ARE PRODUCING CONTINUOUS LIGHTNING...
TORRENTIAL RAINFALL AND REDUCED VISIBILITIES...AND STRONG GUSTY
WINDS. PREVIOUS DISCUSSION FROM 730 PM FOLLOWS...
A FAIRLY TIGHT PRESSURE GRADIENT EXISTS BETWEEN A PIEDMONT TROUGH
NEARLY STATIONARY INLAND AND THE BERMUDA HIGH WELL OFFSHORE. THIS IS
PRODUCING A HEALTHY SOUTH-SOUTHWEST BREEZE AT 15-25 KNOTS THIS
EVENING. ALTHOUGH MODELS SUGGEST WIND SPEEDS WILL RELAX A LITTLE
AFTER MIDNIGHT...THE TIGHT GRADIENT SHOULD REMAIN WITH STRONGER
WINDS REDEVELOPING FRIDAY. SEVERAL CLUSTERS OF THUNDERSTORMS INLAND
ARE WEAKENING AS THEY APPROACH THE COAST...BUT THE POTENTIAL REMAINS
FOR REDEVELOPMENT OF SHOWERS AND STORMS ACROSS THE COASTAL
WATERS...MAINLY FROM LATE THIS EVENING THROUGH ABOUT 3 AM FRIDAY.
THUNDERSTORMS CHANCES ARE SLIGHTLY HIGHER NORTH OF MYRTLE BEACH BUT
I CAN`T RULE OUT STORMS ACROSS THE SC WATERS EITHER.
I HAVE MADE SUBSTANTIAL EDITS TO SEA HEIGHTS BASED ON DATA FROM THE
OCEAN CREST PIER WAVE GAUGE WHICH IS REPORTING 3-4 FT SEAS JUST
OUTSIDE THE SURF ZONE. LARGER SEAS OFTEN PENETRATE RIGHT UP TO THE
BEACHES ON A GOOD ONSHORE WIND HERE...AN EFFECT EVEN OUR HIGH
RESOLUTION "SWAN" WAVE MODEL DOESN`T SEEM TO BE ABLE TO HANDLE.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 PM THURSDAY...A SMALL CRAFT ADVISORY HAS BEEN EXTENDED FOR
ALL AREAS UNTIL 6 PM SAT. THE PRESSURE GRADIENT BETWEEN A PIEDMONT
TROUGH INLAND AND THE BERMUDA RIDGE WILL HELP TO KEEP WINDS AND
SEAS ELEVATED THIS PERIOD. WINDS WILL REACH UP TO 20 TO 25 KT.
WINDS WILL BE SW THROUGH THE PERIOD...SLIGHTLY MORE W OF S ON FRI
THAN ON SAT. SEAS WILL PEAK IN THE 4 TO 7 FT RANGE. SE...8 TO 9
SECOND SWELL... WILL BE WEAK DURING THIS PERIOD AND WAVE HEIGHTS
WILL BE THE RESULT OF INCREASING WIND WAVE ENERGY.
LONG TERM /SUNDAY THROUGH TUESDAY/...
AS OF 3 PM THURSDAY...SOUTHERLY FLOW WILL CONTINUE AROUND WESTERN
PERIPHERY OF BERMUDA HIGH THROUGH EARLY NEXT WEEK. GRADIENT WILL
REMAIN FAIRLY TIGHT THROUGH THE WEEKEND BETWEEN LOW AND PIEDMONT
TROUGH INLAND AND HIGH PRESSURE OFF SHORE. WINDS WILL GENERALLY BE
AROUND 15 KTS NEAR SHORE WITH A SPIKE UP EACH AFTN IN SEA BREEZE.
WINDS WILL BE UP AROUND 20 IN OUTER WATERS AND UP TO 25 KTS IN
WATERS NORTH FRYING PAN. PERSISTENT SOUTHERLY FLOW WILL KEEP SEAS
UP AROUND 4 TO 6 FT THROUGH THE PERIOD. WILL MOST LIKELY END UP
WITH AN EXTENDED PERIOD OF SMALL CRAFT ADVISORY CONDITIONS FOR 6
TO 7 FT SEAS IN STRONGER SOUTHERLY FLOW ESPECIALLY IN OUTER
WATERS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR AMZ250-252-
254-256.
&&
$$
NEAR TERM...TRA
SHORT TERM...RJD
LONG TERM...RGZ
AVIATION...MRR
AREA FORECAST DISCUSSION
NWS RALEIGH NC
935 PM EDT THU JUN 27 2013
.SYNOPSIS...
A WARM AND HUMID AIR MASS WILL HOLD OVER THE REGION FOR THE NEXT
SEVERAL DAYS... AS A LARGE LOW PRESSURE TROUGH HOLDS OVER THE
EASTERN HALF OF THE COUNTRY. PASSING UPPER LEVEL DISTURBANCES WILL
HELP PRODUCE NUMEROUS SHOWERS AND THUNDERSTORMS EACH DAY THROUGH THE
UPCOMING WEEKEND.
&&
.NEAR TERM /THROUGH FRIDAY NIGHT/...
AS OF 935 PM THURSDAY...
THE LAST CLUSTER OF ORGANIZED CONVECTION CONTINUES MOVING TO THE ESE
OVER THE SRN PIEDMONT AND SW SANDHILLS. OTHER MORE ISOLATED CELLS
ELSEWHERE HAVE BECOME STRONG BUT THEIR HIGH-REFLECTIVITY CORES HAVE
NOT QUITE REACHED THE HEIGHTS OF EARLIER STORMS. THE BOUNDARY LAYER
CONTINUES TO SLOWLY BUT STEADILY STABILIZE WITH MLCAPE DOWN TO 1500
J/KG AND GROWING CINH... AND THIS TREND SHOULD CONTINUE WITH STORMS
DISSIPATING IN THE NEXT FEW HOURS. THE LATEST COUPLE OF HRRR RUNS AS
WELL AS THE SREF AND WRF SUPPORT THIS SCENARIO WITH REMAINING STORMS
SHIFTING TO OUR EAST AND WEAKENING. DYNAMIC SUPPORT FOR ASCENT WILL
BE WANING AS THE VORTICITY AXIS SHIFTS TO OUR EAST... LEAVING BEHIND
BAGGY MID LEVEL TROUGHING OVERNIGHT WITH A LINGERING DIFFUSE TROUGH
AT THE SURFACE THROUGH THE CENTRAL CAROLINAS. WILL HOLD ONTO
EXISTING FORECAST TREND OF POPS DECREASING WEST TO EAST. EXPECT FAIR
TO PARTLY CLOUDY SKIES OVERNIGHT... ALTHOUGH THE MORE WIDESPREAD
SHOWERS/STORMS IN THE EAST ALONG WITH SLIGHTLY HIGHER DEW POINTS AND
925-850 MB MOISTURE SHOULD YIELD MORE WIDESPREAD STRATUS IN OUR
EAST. WITH THE RAIN-COOLED AIR IN SOME AREAS... CURRENT TEMPS HAVE
FALLEN TO WITHIN A FEW DEGREES OF THE DEW POINT AND HENCE ARE CLOSE
TO THE NIGHTTIME LOWS. CURRENT TEMP TRENDS PLUS STATISTICAL GUIDANCE
SUPPORT LOWS CLOSE TO THE CURRENT FORECAST OF 69-74. -GIH
FRIDAY...
SHORTWAVE ENERGY DIGGING THROUGH THE UPPER MIDWEST WILL CONTINUE TO
DEEPEN THE UPPER LEVEL TROUGH DEVELOPING OVER THE EASTERN US. A
SHARP PIEDMONT TROUGH WILL BE IN PLACE DURING THE DAY ON
FRIDAY..WITH LITTLE CHANGE IN AIRMASS EXPECTED OUTSIDE OF SLIGHTLY
LOWER DEWPOINTS IN THE WESTERN PIEDMONT. CYCLONIC FLOW
ALOFT...ALBEIT WITHOUT A NOTABLE TRIGGER IN THE MODELS...AND MODEST
INSTABILITY WILL ONCE AGAIN SUPPORT SCATTERED TO NUMEROUS
THUNDERSTORMS DURING THE AFTERNOON. WHILE ITS POSSIBLE THAT
COVERAGE MAY NOT BE AS GREAT AS THIS AFTERNOON...MID-LEVEL FLOW WILL
BE STRONGER AND DEEP LAYER SHEAR IS PROGGED TO TO EXCEED
30KT...SUGGESTING MULTICELLULAR ORGANIZATION. THE CURRENT SPC DAY
TWO OUTLOOK INCLUDES ALL OF CENTRAL NC IN A SLIGHT RISK.
REGARDING HIGH TEMPS...GUIDANCE ALMOST UNANIMOUSLY GIVES VALUES A
FEW DEGREES WARM THAN TODAY...WITH LOWER 90S ACROSS A LARGE PORTION
OF THE CWA. THIS WILL LIKELY LEAD TO HEAT INDICES NEAR 100 ACROSS
THE SANDHILLS AND SOUTHERN PIEDMONT WHERE DEWPOINTS SHOULD HOVER IN
THE LOWER 70S.
FRIDAY NIGHT...
WILL CONTINUE AT LEAST A SLIGHT CHANCE OF SHOWERS AND STORMS THROUGH
FRIDAY NIGHT AS HEIGHTS CONTINUE TO SLOWLY FALL ALOFT AND THE
AIRMASS OVER NC REMAINS HUMID. LOWS IN THE UPPER 60S AND LOWER 70S.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300 PM THURSDAY...
AN ANOMALOUSLY AMPLIFIED PATTERN WILL PREVAIL ACROSS THE CONUS
THROUGH THE WEEKEND...CHARACTERIZED BY A DEEP UPPER LEVEL RIDGE OVER
THE ROCKIES/INTERMOUNTAIN WEST AND DEEP TROUGHING EAST OF THE
MISSISSIPPI...WITH A PERSISTENT UPPER LEVEL LOW CENTERED IN VICINITY
OF THE LOWER GREAT LAKES AND OH VALLEY. ACROSS THE CAROLINAS AND
MID-ATLANTIC...EXPECT ATYPICALLY STRONG SOUTHWEST FLOW ALOFT WITH
NUMEROUS SMALL AMPLITUDE SHORTWAVES CROSSING THE REGION THROUGHOUT
THE PERIOD IN THE PRESENCE OF A SEASONABLY MOIST AIRMASS. AS A
RESULT...EXPECT ABOVE NORMAL CHANCES FOR SHOWERS AND THUNDERSTORMS
AND SLIGHTLY BELOW NORMAL HIGH TEMPS IN THE MID 80S...DEPENDING ON
CLOUD COVER AND CONVECTION. THE EXACT COVERAGE AND PERSISTENCE OF
CONVECTION WILL HIGHLY DEPEND ON THE EVOLUTION OF SMALL AMPLITUDE
DISTURBANCES IN SW FLOW ALOFT AND THE TIMING OF THESE DISTURBANCES
IN RELATION TO THE DIURNAL HEATING CYCLE. FURTHERMORE...THE DEGREE
OF DIURNAL DESTABILIZATION IS DIFFICULT TO ASCERTAIN GIVEN INCREASED
CLOUD COVER AND AN ABOVE NORMAL CHANCE FOR NOCTURNAL OR EARLY
MORNING CONVECTION...THOUGH ONE WOULD EXPECT AT LEAST SOME CLOUD
BREAKS AND AREAS OF RELATIVELY STRONGER INSOLATION DURING PEAK
HEATING. EITHER WAY...SLIGHTLY STEEPER MID-LEVEL LAPSE RATES /COOLER
TEMPS ALOFT/ IN ASSOCIATION WITH THE UNUSUALLY AMPLIFIED UPPER LEVEL
TROUGH OVER THE REGION WILL AT LEAST SOMEWHAT COMPENSATE FOR
DECREASED INSOLATION. GIVEN DEEP-LAYER (0-6 KM) SHEAR LIKELY IN THE
35-45 KT RANGE...ORGANIZED CONVECTION WILL CERTAINLY BE POSSIBLE...
INCLUDING SUPERCELLS...THOUGH THE TYPE/EXTENT OF ANY SEVERE THREAT
CANNOT BE PRECISELY IDENTIFIED AT THIS TIME. IN ADDITION TO A
POTENTIAL FOR SEVERE THUNDERSTORMS...ISOLATED FLASH FLOODING WILL
ALSO BE POSSIBLE GIVEN RECENT HEAVY RAINFALL AND ABOVE NORMAL
CHANCES FOR CONVECTION THROUGH THE WEEKEND. -VINCENT
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300 PM THURSDAY...
AN UNSEASONABLY AMPLIFIED UPPER LEVEL PATTERN WILL PERSIST ACROSS
THE CONUS THROUGH THE MIDDLE OF NEXT WEEK...CHARACTERIZED BY RIDGING
OVER THE INTERMOUNTAIN WEST...TROUGHING CENTERED IN VICINITY OF THE
MS RIVER VALLEY AND ATYPICALLY STRONG SW FLOW ALOFT OVER THE
CAROLINAS. NUMEROUS SMALL AMPLITUDE DISTURBANCES IN THE PRESENCE OF
ABOVE NORMAL MOISTURE (PWAT ~2.00") WILL RESULT IN ABOVE NORMAL
CHANCES FOR SHOWERS AND THUNDERSTORMS THROUGH EARLY/MID NEXT WEEK...
MODULATED PRIMARILY BY THE DIURNAL HEATING CYCLE...IN ADDITION TO A
CONTINUED THREAT FOR SEVERE WEATHER (GIVEN FAVORABLE DEEP-LAYER
SHEAR) AND ISOLD FLASH FLOODING. IN GENERAL EXPECT HIGHS SEVERAL
DEGREES BELOW NORMAL DUE TO INCREASED CLOUD COVER AND CHANCES FOR
CONVECTION. -VINCENT
&&
.AVIATION /00Z THURSDAY THROUGH TUESDAY/...
AS OF 745 PM THURSDAY...
SCATTERED STORMS WILL SWEEP ACROSS CENTRAL NC THROUGH 04Z. RWI/FAY
ARE THE TAF LOCATIONS MOST LIKELY TO BE AFFECTED... HOWEVER THE
CHANCE OF A STORM PASSING OVER ANY PARTICULAR TAF SITE IS TOO REMOTE
TO INCLUDE AS A PREVAILING CONDITION. MOST STORMS THIS EVENING WILL
BE CIRCUMNAVIGABLE. OTHERWISE... VFR CONDITIONS ARE EXPECTED TO HOLD
THROUGH TONIGHT... WITH THE EXCEPTION OF FAY WHERE VERY MOIST AIR
AND A MOIST GROUND FROM TODAY`S STORMS WILL FOSTER DEVELOPMENT OF
IFR/LIFR STRATUS AND MVFR/IFR FOG 07Z-12Z TONIGHT/FRIDAY MORNING.
THIS SHOULD LIFT BY 15Z... THEN VFR CONDITIONS SHOULD HOLD AT ALL
SITES THROUGH 18Z. ANOTHER ROUND OF SCATTERED TO NUMEROUS STORMS
OVER CENTRAL NC IS LIKELY AS WE APPROACH THE END OF THE TAF VALID
PERIOD.
LOOKING BEYOND 18Z FRIDAY... SHOWERS/STORMS SHOULD BE NUMEROUS
ENOUGH FOR A GOOD CHANCE OF LOCALLY HEAVY RAIN AND A PERIOD OF
IFR/LIFR CONDITIONS AT CENTRAL NC TAF SITES MAINLY FROM 18Z-00Z. AS
VERY LITTLE CHANGES IN THE OVERALL REGIME WITH WARM AND HUMID AIR
AND A LOW PRESSURE TROUGH WITH A SERIES OF DISTURBANCES PASSING
OVERHEAD... NEARLY DAILY SHOWER/STORM CHANCES WITH BRIEF MVFR OR IFR
CONDITIONS ARE POSSIBLE EACH AFTERNOON/EARLY EVENING... AND A PERIOD
OF IFR STRATUS OR FOG MAY OCCUR EARLY EACH MORNING. -GIH
&&
.EQUIPMENT...
KRAX WSR-88D WILL BE REMAIN DOWN OR IN DEGRADED MODE THROUGH FRIDAY
MORNING. KRAX HAS BEEN IN A SEVERELY DEGRADED MODE FOR SEVERAL
DAYS... AND THE NEEDED REPAIRS WERE DEEMED TO BE CRITICAL. THE TEAM
OF TECHNICIANS WILL MAKE THESE REPAIRS AS QUICKLY AS POSSIBLE... AND
IS WORKING TO RETURN THE RADAR TO NORMAL SERVICE BY EARLY AFTERNOON
FRIDAY. WE APOLOGIZE FOR THE INCONVENIENCE. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD/BLS
SHORT TERM...VINCENT
LONG TERM...VINCENT
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
307 PM EDT WED JUN 26 2013
.SYNOPSIS...
INCREASINGLY UNSETTLED WEATHER IS EXPECTED FOR THE REMAINDER OF
THE WEEK INTO THE WEEKEND AS LOWER PRESSURE ALOFT DEEPENS OVER
THE REGION. SHOWERS AND THUNDERSTORMS WILL FIRE EACH DAY ALONG
AN INLAND SURFACE TROUGH...AS WELL AS THE SEA BREEZE. DAYTIME
AND NIGHTTIME TEMPERATURES WILL HOLD CLOSE TO NORMAL FOR LATE
JUNE TO EARLY JULY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 3 PM WEDNESDAY...CONVECTIVE CLUSTER TRACKING EASTWARD ALONG
A SEA-BREEZE FRONT OVER BRUNSWICK COUNTY WILL BE MONITORED CLOSELY
IN THE VERY NEAR TERM. SPS HAS HIGHLIGHTED OUR AREA FOR ISOLATED
SEVERE STORMS AIDED BY CONVERGENCE BUT A WATCH APPEARS UNLIKELY.
OTHER CELLS COULD THREATEN OUR NORTHERN ZONES FROM RED SPRINGS TO
ELIZABETHTOWN THROUGH AFTERNOON. WEST OF ALL THIS ACTIVITY THERE
APPEARS TO BE ONLY ISOLATED CONVECTION DUE TO SUBSIDENCE BEHIND
THE SHORT WAVE IMPULSE LIKELY RESPONSIBLE FOR THE CURRENT
CONVECTION. DIURNAL COOLING IN EARLY EVENING SHOULD ALLOW CELLS TO
ABATE IN COVERAGE AND INTENSITY. LOWS OVERNIGHT LOW TO MIDDLE 70S
EXPECTED WITH LOW-LEVEL WINDS STAYING UP A BIT OVERNIGHT.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...BERMUDA HIGH AND PIEDMONT TROUGH CONTINUE
TO BE THE MAIN SURFACE FEATURES WHILE ALOFT WEAK LONGWAVE 5H
TROUGH REPLACES FLAT RIDGING. MID LEVEL HEIGHT FALLS COMBINED WITH
INCREASING LOW LEVEL THICKNESS LEADS TO AN INCREASE IN INSTABILITY
DURING THE PERIOD. DEEP MOISTURE IN PLACE THU...PRECIPITABLE WATER
VALUES APPROACH 2 INCHES...DECREASES A LITTLE FRI...PWATS DROP
CLOSER TO 1.6 INCH IN THE AFTERNOON...AS MID LEVEL TROUGH AXIS
SHIFTS EAST. BRIEF PERIOD OF DEEP WEST TO NORTHWEST FLOW FRI
AFTERNOON AND EVENING WILL HELP LIMIT CONVECTION BUT STRENGTHENED
PIEDMONT TROUGH MAY OFFSET THE WEAK MID LEVEL SUBSIDENCE.
SEA BREEZE AND PIEDMONT TROUGH SHOULD BOTH BE ACTIVE EACH
AFTERNOON WITH SEA BREEZE BEING HELD CLOSER TO THE COAST BY MORE
WESTERLY FLOW...ESPECIALLY FRI. GIVEN THE LACK OF ANY SIGNIFICANT
INTENSIFYING MID LEVEL FEATURES AND POTENTIAL FOR NUMEROUS
OUTFLOWS DO NOT THINK COVERAGE CAN BE CONFINED TO ONE LOCATION.
COASTAL AREAS ARE LIKELY FAVORED EARLIER IN THE DAY WITH HIGH POP
SHIFTING INLAND LATER IN THE DAY AS PIEDMONT TROUGH ACTIVITY MOVES
INTO THE REGION. HEAVY RAIN REMAINS A CONCERN...ESPECIALLY WITH
TRAINING STORMS...BUT CANNOT RULE OUT A WET MICROBURST OR HAIL
GIVEN THE COOLING MID LEVELS.
TEMPERATURES WILL BE NEAR TO ABOVE CLIMO WITH HIGHS IN THE UPPER
80S TO LOWER 90S AND LOWS IN THE LOW TO MID 70S.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 3 PM WEDNESDAY...DEEP SOUTHERLY FLOW OF WARM AND MOIST AIR
WILL CONTINUE THROUGH THE WEEKEND INTO NEXT WEEK AS LOCAL AREA
REMAINS ON THE WESTERN PERIPHERY OF BERMUDA RIDGE AND EASTERN EDGE
OF MID TO UPPER TROUGH TO OUR WEST. A MID TO UPPER LOW ROTATES
AROUND THE GREAT LAKES AND DIGS DOWN THROUGH THE OHIO VALLEY INTO
THE LOWER MISSISSIPPI VALLEY THROUGH THE WEEKEND INTO EARLY NEXT
WEEK. MID TO UPPER LEVEL ENERGY WILL ROTATE AROUND THIS TROUGH UP
THROUGH OUR LOCAL AREA PROVIDING ADDITIONAL SUPPORT TO ENHANCE
CONVECTION OVER THE EASTERN CAROLINAS OVER THE WEEKEND INTO EARLY
NEXT WEEK. BASICALLY WILL CONTINUE WITH WARM AND HUMID AIR MASS
OVER THE AREA WITH PLENTY OF CLOUDS AND AND CHANCE OF SHWRS/TSTMS
EACH DAY. PCP WATER VALUES REMAIN NEAR 2 INCHES OR GREATER THROUGH
MOST OF THE PERIOD. MOISTURE PROFILES SHOW VERY DEEP MOISTURE WITH
RH VALUES GREATER THAN 90% THROUGH MOST LEVELS ABOVE 10K FT. TEMPS
WILL RUN NEAR OR ABOVE NORMAL THROUGH THE PERIOD WITH 70S FOR
OVERNIGHT LOWS AND CLOSE TO 90 FOR AFTERNOON HIGHS.
BY MID WEEK NEXT WEEK THE MID TO UPPER TROUGH OVER THE MID SECTIONS
OF THE CONUS RETROGRADES AND WEAKENS ALLOWING FOR A STRONG RIDGE
OVER THE ATLANTIC TO BUILD WESTWARD INTO THE AREA. THIS SHOULD
PROVIDE DRYING THROUGH THE MID TO UPPER LEVELS AND INCREASED
SUBSIDENCE LEADING TO DRIER WEATHER BY WED OR THURS TIME FRAME.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
AS OF 17Z...WATER VAPOR IMAGERY SHOWS AN UPPER IMPULSE APPROACHING
OUR SOUTHERN TERMS...AND SOME WEAK CONVECTION HAS ALREADY DEVELOPED
WEST OF OUR CWA THIS MORNING. HAVE INCLUDED VCTS FOR ALL TERMS THIS
AFTN AS ISO STORMS ARE EXPECTED TO FIRE ALONG THE DEVELOPING SEA
BREEZE SHORTLY. THE LATEST HRRR RUNS INDICATE THE WESTERLY STEERING
FLOW MAY KEEP SEA BREEZE STORMS PINNED NEAR THE COAST. CONVECTION IS
POSSIBLE INLAND AS WELL AS THE UPPER IMPULSE NEARS OUR WESTERN
TERMS. EXPECT PREVAILING VFR AT ALL TERMS WITH BRIEF PERIODS OF
MVFR/IFR IN +SHRA/TSRA...AND PERHAPS BETTER PCPN COVERAGE AT
KFLO/KMYR/KCRE.
CONVECTION SHOULD RAPIDLY DIMINISH AFTER 00Z. CANNOT RULE OUT
POCKETS OF FOG/STRATUS OVERNIGHT...BUT GIVEN STRONG LOW-LEVEL WINDS
AND LACK OF DEVELOPMENT THIS MORNING...CONFIDENCE IS LOW ATTM. AN
APPROACHING SHORTWAVE/SFC TROUGH ON THURSDAY MAY BRING MORE
WIDESPREAD SHOWERS/T-STORMS TO OUR AREA.
EXTENDED OUTLOOK...ISO/SCT AFTERNOON SHOWERS AND T-STORMS THROUGH
MONDAY WITH BRIEF LOCALIZED PERIODS OF MVFR/IFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 3 PM WEDNESDAY...SW FLOW TO PICK UP A BIT AS LOW PRESSURE
INLAND DEEPENS A BIT...AND SW 15-20 KT IS EXPECTED REMAINDER OF
THE AFTERNOON AND OVERNIGHT INTO EARLY THURSDAY. SEAS 3-4 FEET
EXPECTED IN A MIX OF 3 FOOT SSW WAVES EVERY 5 SECONDS AND SE WAVES
1-2 FEET EVERY 8-9 SECONDS. TSTMS WILL BE POSSIBLE ON THE WATERS
THROUGH DAYBREAK THURSDAY.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...SOUTHWEST FLOW WILL CONTINUE THROUGH THE
PERIOD AS WATERS REMAIN BETWEEN BERMUDA HIGH AND STRENGTHENING
PIEDMONT TROUGH. WIND SPEEDS WILL INCREASE AS TROUGH BECOMES MORE
DEFINED THU INTO FRI. WINDS INCREASE FROM 15 TO 20 KT THU TO A SOLID
20 KT FOR FRI. IN RESPONSE TO INCREASING WINDS SEAS WILL BUILD FROM
3 TO 5 FT ON THU TO 3 TO 6 FT LATE THU NIGHT THROUGH FRI NIGHT.
HIGHEST SEAS WILL BE NEAR 20 NM AND IN AREAS OPEN TO EXTENDED
SOUTHWEST FETCH...MAINLY IN AND AROUND FRYING PAN SHOALS.
LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 3 PM WEDNESDAY...SOUTHERLY FLOW WILL CONTINUE AROUND
WESTERN PERIPHERY OF BERMUDA HIGH THROUGH THE WEEKEND INTO EARLY
NEXT WEEK. WINDS WILL GENERALLY BE 10 TO 15 KTS WITH A SPIKE UP
EACH AFTN IN SEA BREEZE. PERSISTENT SOUTHERLY FLOW WILL KEEP SEAS
UP AROUND 4 TO 6 FT THROUGH THE PERIOD. MAY END UP WITH AN
EXTENDED PERIOD WITH A SMALL CRAFT ADVISORY FOR 6 FT SEAS IN
STRONGER SOUTHERLY FLOW ESPECIALLY IN OUTER WATERS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...COLBY
SHORT TERM...III
LONG TERM...RGZ
AVIATION...BJR/COLBY
AREA FORECAST DISCUSSION...COR
NWS WILMINGTON NC
107 PM EDT WED JUN 26 2013
.SYNOPSIS...
INCREASINGLY UNSETTLED WEATHER IS EXPECTED FOR THE REMAINDER OF
THE WEEK INTO THE WEEKEND AS LOWER PRESSURE ALOFT DEEPENS OVER
THE REGION. SHOWERS AND THUNDERSTORMS WILL FIRE EACH DAY ALONG
AN INLAND SURFACE TROUGH...AS WELL AS THE SEA BREEZE. DAYTIME
AND NIGHTTIME TEMPERATURES WILL HOLD CLOSE TO NORMAL FOR LATE
JUNE TO EARLY JULY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 10 AM WEDNESDAY...STEERING FLOW TODAY WILL GUIDE CONVECTION
TO THE E-ESE AROUND 15 MPH. SUBTLE SHORT-WAVE IMPULSES EXTENDING
FROM WESTERN VA/NC INTO CENTRAL SC EVIDENT IN WATER VAPOR PICTURES
FROM SPACE APPEARS TO BE AIDING MODERATELY STRONG CONVECTION
PRESENTLY SOUTH OF COLUMBIA SC THIS MORNING...AND THIS WILL LIKELY
STIR UP ACTIVITY OVER OUR W AND SW ZONES INTO THE LATE MORNING AND
EARLY AFTERNOON. LATEST 12Z RAOB DATA SHOWS MINOR CAPS ALOFT AT
725MB 600MB AND 475MB...BUT THEY ARE WEAK AND SEE NO REASON WHY
THESE SMALL BARRIERS CANNOT BE ERODED BY UPDRAFTS LATER TODAY.
THIS MAY BE PARTICULARLY TRUE WITH PWAT VALUES AROUND 1.85 INCHES
TODAY. THUS WE ALSO EXPECT CONVECTION TO FIRE ALONG THE INLAND
MARCHING SEA-BREEZE FRONT DURING THE AFTERNOON. RADAR TRENDS AND
WPC QPF DEPICTIONS POINT TO POTENTIALLY HEFTY RAINFALL AMOUNT
FAVORED OVER WILLIAMSBURG AND GEORGETOWN COUNTIES SOUTHWARD INTO
THE CHS FORECAST ZONES. FORTUNATELY THE STORM MOTION DOES NOT
POSE AN OVERBEARING FLOOD THREAT...BUT GROUNDS DO REMAIN WET.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
AS OF 3 AM WEDNESDAY... MID LEVEL TROUGHINESS DROPS INTO THE EASTERN
U.S. ON THURSDAY. LOCAL STEERING FLOW TURNS TO THE WNW AND BL SWRLY
FLOW INCREASES. SEA BREEZE NOT EXPECTED TO MAKE MUCH INLAND PROGRESS
AND STORMS MAY FIRE JUST ABOUT ANYWHERE. SEABREEZE STORMS WILL BE
ABLE TO AFFECT AREA BEACHES. SHORTWAVE PROGGED TO CROSS THE REGION
DURING THE AFTERNOON AND EVENING WHICH MAY ENHANCE TSTM COVERAGE. PW
REMAINS ABOVE 2 INCHES AND SO STORMS WILL YIELD HEAVY RAINFALL.
STORM MOTION WILL BE NEARLY DOUBLE THAT OF DAYS PRIOR TO HOPEFULLY
MITIGATE FLOODING POTENTIAL EXCEPT WHERE ANY TRAINING OCCURS. WET
DOWNBURST HARD TO RULE OUT AS WELL SINCE MLCAPE MAY BE IN THE
1000-1500 J/KG RANGE ON THURSDAY AND POSSIBLY OVER 2000 J/KG ON
FRIDAY. FRIDAY ALSO LOOKS QUITE ACTIVE WHILE NO APPRECIABLE
SHORTWAVES APPEAR IN THE MODELS A WELL DEFINED PIEDMONT TROUGH WILL
BE IN PLACE. ALTHOUGH THIS FEATURE WILL BE TO OUR WEST STORMS WILL
ONCE AGAIN PROPAGATE EASTWARD. BETWEEN THOSE STORMS THAT GET WESTERN
ZONES AND ANOTHER DAY OF AN ACTIVE SEABREEZE ITS HARD TO PICK OUT
ANY FAVORED AREAS FOR TSTMS...MADE EVEN MORE TRUE BY THE NUMEROUS
OUTFLOW BOUNDARIES THAT MAY LINGER FROM THURSDAY STORMS.
TEMPERATURES WILL BE VERY NEAR CLIMO THROUGH THE PERIOD.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 3 AM WEDNESDAY...A COLD FRONT WILL LIE STALLED OVER THE
WESTERN CAROLINAS FOR MOST OF THE PERIOD AS UPPER LEVEL PATTERN
AMPLIFICATION HOLDS UP ANY EASTWARD PROGRESSION. RIDGES OVER WEST
ATLANTIC AND JUST WEST OF THE ROCKIES WITH A TROUGH FROM GREAT LAKES
TO LOWER MS. CAROLINA COASTS WILL REMAIN IN THE DEEP SSWRLY MOISTURE
FLOW AHEAD OF THE BOUNDARY AND BE QUITE PRONE TO FAIRLY WIDESPREAD
SHOWERS AND THUNDERSTORMS. AT THIS POINT ITS HARD TO TELL IF ANY
GIVEN DAY OF THE EXTENDED HAS ANY HIGHER OR LOWER RAIN CHANCES THAN
THE OTHERS. TEMPERATURES WILL BE VERY CLOSE TO CLIMO BUT INCREASING
CLOUD COVER COULD TRIM A FEW DEGREES FROM HIGHS WHILE ADDING THE
SAME TO LOWS.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 17Z...WATER VAPOR IMAGERY SHOWS AN UPPER IMPULSE APPROACHING
OUR SOUTHERN TERMS...AND SOME WEAK CONVECTION HAS ALREADY DEVELOPED
WEST OF OUR CWA THIS MORNING. HAVE INCLUDED VCTS FOR ALL TERMS THIS
AFTN AS ISO STORMS ARE EXPECTED TO FIRE ALONG THE DEVELOPING SEA
BREEZE SHORTLY. THE LATEST HRRR RUNS INDICATE THE WESTERLY STEERING
FLOW MAY KEEP SEA BREEZE STORMS PINNED NEAR THE COAST. CONVECTION IS
POSSIBLE INLAND AS WELL AS THE UPPER IMPULSE NEARS OUR WESTERN
TERMS. EXPECT PREVAILING VFR AT ALL TERMS WITH BRIEF PERIODS OF
MVFR/IFR IN +SHRA/TSRA...AND PERHAPS BETTER PCPN COVERAGE AT
KFLO/KMYR/KCRE.
CONVECTION SHOULD RAPIDLY DIMINISH AFTER 00Z. CANNOT RULE OUT
POCKETS OF FOG/STRATUS OVERNIGHT...BUT GIVEN STRONG LOW-LEVEL WINDS
AND LACK OF DEVELOPMENT THIS MORNING...CONFIDENCE IS LOW ATTM. AN
APPROACHING SHORTWAVE/SFC TROUGH ON THURSDAY MAY BRING MORE
WIDESPREAD SHOWERS/T-STORMS TO OUR AREA.
EXTENDED OUTLOOK...ISO/SCT AFTERNOON SHOWERS AND T-STORMS THROUGH
MONDAY WITH BRIEF LOCALIZED PERIODS OF MVFR/IFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 10 AM WEDNESDAY...SW WIND SPEEDS 15 KT EXPECTED TODAY. THE
SEA BREEZE CIRCULATION WILL PUSH NEARSHORE WIND SPEEDS TO 15 TO 20
KT IN THE MID AFTERNOON THROUGH EARLY EVENING. SEA HEIGHTS WILL
RUN 3 TO 4 FT...IN A MIX OF SSW WIND WAVES 2-3 FEET EVERY 5 SEC
AND SE WAVES 1-2 FEET EVERY 8 SEC. A FEW TSTMS WILL BE POSSIBLE
LATER THIS AFTERNOON INTO THIS EVENING...AS THE STEERING FLOW
PUSHES TSTMS GENERALLY WEST TO E-ESE.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...PIEDMONT TROUGH DEVELOPS ON THURSDAY AND
STRENGTHENS THURSDAY NIGHT. SWRLY GRADIENT WINDS TO INCREASE AND
THE RESULTING SEAS COULD YIELD SMALL CRAFT ADVISORY FOR 6 FT SEAS
OVER NRN ZONES. THE BOUNDARY WILL REMAIN TO OUR WEST INTO FRIDAY
AND HIGH PRESSURE REMAINS ANCHORED ACROSS MUCH OF THE WEST
ATLANTIC. LITTLE IF ANY CHANGES THUS EXPECTED IN WINDS AND SEAS.
SOUTHERN ZONES MAY STAY CAPPED AT 5 FT SEAS AND SCEC MAY OR MAY
NOT BE NEEDED...PERHAPS HINGING ON HOW MUCH SWELL ENERGY MAKES IT
INTO THE FORECAST ZONES.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3 AM WEDNESDAY...THE WEEKEND LOOKS TO OFFER UNSETTLED
CONDITIONS CONTINUING FROM THOSE OF THE SHORT TERM. SQUEEZE PLAY
BETWEEN PIEDMONT TROUGH OVER LAND AND STRONG WEST ATLANTIC HIGH TO
KEEP WIND AND SEAS AGITATED MORE THAN TYPICAL OF START OF JULY.
NORTHERN ZONES PROBABLY LOOKING AT CONTINUATION OF LONG DURATION
ADVISORY WHILE SOUTHERN ZONES CLOSER TO CUSP OF ADVISORY VS JUST
SCEC HEADLINES. SOME 6FT SWELL ENERGY COULD MAKE IT INTO SC
WATERS...ITS A LITTLE TOO EARLY TO TELL.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...COLBY
SHORT TERM...BACON
LONG TERM...MBB
AVIATION...BJR/COLBY
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
225 PM CDT WED JUN 26 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 225 PM CDT WED JUN 26 2013
THIS EVENING...FORCING FROM APPROACHING SHORTWAVE CAN BE SEEN IN
RADAR IMAGERY WITH WEAK RETURNS ACROSS CENTRAL NORTH DAKOTA.
RAP/HRRR ALSO INDICATE A WEAK 925MB LOW THAT WOULD PROPAGATE FROM
NW ND INTO SE ND THROUGH THE EVENING HOURS. LAPS ANALYSIS
INDICATES MLCAPE 1000-2000 J/KG...AND DEEP LAYER SHEAR APPROACHING
50 KNOTS. THERE HAS BEEN SOME DRYING OF THE DEW POINTS ACROSS
EASTERN NORTH DAKOTA...BUT THIS HAS HALTED AND VALUES HAVE RISEN A
DEGREE OR TWO THE PAST HOUR. LOW LEVEL CONVERGENCE IS RATHER
WEAK...WHICH WILL LIMIT AREAL COVERAGE. HOWEVER...THERE IS ENOUGH
SUPPORT IN PLACE FOR AT LEAST A COUPLE STRONGER STORMS (MAIN
THREAT LARGE HAIL AND STRONG WIND GUSTS).
THURSDAY-THURSDAY NIGHT...UPPER RIDGE WILL BEGIN TO BUILD ACROSS
THE WESTERN CONUS AND DEVELOP NORTHWEST FLOW ALOFT OVER THE
REGION. COOL AIR ALOFT AND A WEAK MID-LEVEL TROUGH COULD LEAD TO
AFTERNOON SHOWERS ACROSS NW MN. OTHERWISE...BREEZY AFTERNOON WINDS
AND TEMPERATURES NEAR NORMAL.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 225 PM CDT WED JUN 26 2013
FRIDAY-SATURDAY...WESTERN CONUS RIDGE WILL CONTINUE TO BUILD AND
DEVELOP MORE NORTHERLY FLOW ALOFT. A FEW SHORTWAVES WILL MOVE
THROUGH THE REGION...BRINGING SCATTERED SHOWER CHANCES (AND
PROBABLY THUNDER SINCE THERE WILL LIKELY BE SOME INSTABILITY).
TEMPERATURES WILL BE A BIT COOLER.
SATURDAY NIGHT-WEDNESDAY...THERE IS GENERAL AGREEMENT AMONG
MODELS WITH AN AMPLIFYING MID/UPPER LEVEL RIDGE ACROSS THE WESTERN
CONUS EARLY IN THE PERIOD...WITH NORTHWEST FLOW ALOFT ACROSS THE
NORTHERN PLAINS. MAINLY DRY AND SEASONABLE CONDITIONS ARE EXPECTED
FOR SUNDAY WITH WEAK SFC HIGH PRESSURE IN PLACE. BEYOND
SUNDAY...THE PRIMARY CHALLENGE WILL BE CONVECTIVE CHANCES WITHIN
THE NW FLOW PATTERN. MOST MODEL GUIDANCE SUGGESTS SOME EMBEDDED
WAVES DROPPING SOUTH DURING THE MONDAY-WEDNESDAY PERIOD...WITH
PERIODIC CHANCES FOR PRECIPITATION. THE 00Z ECMWF WAS A BIT
FARTHER EAST WITH THE RIDGE AXIS...WHICH WOULD RESULT IN A DRIER
PATTERN OVER THE AREA. THUS...KEPT SLIGHT/CHANCE ALLBLEND POPS
GOING AS MODEL UNCERTAINTY INCREASES LATER IN THE PERIOD.
TEMPERATURES ARE EXPECTED TO REMAIN FAIRLY SEASONABLE THROUGH THE
PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1255 PM CDT WED JUN 26 2013
SCT TO BKN MAINLY VFR CU FIELD WILL CONTINUE THROUGH THE
AFTERNOON...WITH CIGS OCCASIONALLY DROPPING INTO THE MVFR RANGE
ESPECIALLY EAST OF THE VALLEY. DID UTILIZE 15Z HRRR TO INCLUDE MOST
PROBABLE TIME PERIOD FOR CONVECTIVE ACTIVITY WITH THE PASSAGE OF A
SFC TROUGH THIS AFTERNOON/EVENING. WITH SCATTERED NATURE OF
ACTIVITY...WENT WITH VCTS FOR NOW. WEST WINDS THIS AFTERNOON WILL
SUBSIDE THIS EVENING...BEFORE INCREASING AGAIN OUT OF THE WEST TO
NORTHWEST BY MID TO LATE MORNING THURSDAY.
&&
.HYDROLOGY...
ISSUED AT 1255 PM CDT WED JUN 26 2013
ALL RIVERS AROUND FARGO ARE SEEING SHARP RISES AT THE PRESENT TIME.
IT APPEARS THAT THE RED AT FARGO WILL APPROACH MAJOR FLOOD STAGE
WITHIN THE NEXT COUPLE OF DAYS. SIMULATIONS INDICATE THAT POINTS
DOWNSTREAM OF FARGO WILL ALSO APPROACH OR EXCEED MINOR FLOOD STAGE
IN SEVERAL DAYS...FROM HALSTAD THROUGH OSLO MN. AN AREAL FLOOD
WARNING REMAINS IN EFFECT FOR WILKIN AND RICHLAND COUNTIES...AND A
FLOOD ADVISORY HAS BEEN POSTED FOR CASS COUNTY.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...TG
LONG TERM...TG/MAKOWSKI
AVIATION...MAKOWSKI
HYDROLOGY...WJB
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1255 PM CDT WED JUN 26 2013
.UPDATE...
ISSUED AT 1255 PM CDT WED JUN 26 2013
MAIN CONCERN FOR TODAY WILL BE MARGINAL SEVERE THUNDERSTORM
CHANCES. LAPS ANALYSIS INDICATES MLCAPE ALONG AND WEST OF THE
VALLEY 1000-1500 J/KG...AND 500-1000 J/KG EAST OF THE VALLEY.
THERE HAS NOT YET BEEN ENOUGH HEATING TO BREAK THE CAP...AND THINK
WE SHOULD REMAIN DRY UNTIL AT LEAST MID-AFTERNOON. A BIT MORE
HEATING COMBINED WITH FORCING FROM APPROACHING SHORTWAVE AND JET
STREAK WILL LIKELY LEAD TO CONVECTIVE INITIATION. DEEP LAYER SHEAR
INCREASES TO AROUND 50 KNOTS...WHICH COMBINED WITH THE INSTABILITY
IN PLACE SHOULD LEAD TO A COUPLE STRONGER STORMS. EXPECTED
COVERAGE NOT ENOUGH TO WARRANT A SLIGHT RISK FROM SPC...OR T+ IN
THE GRIDS. PREVIOUS UPDATE APPEARS TO HANDLE THE SITUATION WELL.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 328 AM CDT WED JUN 26 2013
FOR THE REST OF TODAY...THE SURFACE LOW AND ASSOCIATED COLD FRONT
WILL MOVE INTO THE MN ARROWHEAD. A SOMEWHAT DRIER AIR MASS WITH
DEW POINTS IN THE UPPER 50S TO MID 60S WILL MOVE INTO THE REGION.
SHOULD SEE DECREASING CLOUD COVER UNTIL THIS AFTERNOON WITH SOME
THERMAL CU POSSIBLE GIVEN CONVECTIVE TEMPERATURES IN THE MID TO
UPPER 80S. OUTSIDE OF THE NORTHEAST FORECAST AREA...WILL KEEP 20
POPS THROUGH THE DAY FOR A STRAY SHOWER OR THUNDERSTORM.
TEMPERATURES SHOULD BE A TAD COOLER TODAY...ESPECIALLY ACROSS THE
NORTHEAST...BUT WITH NO MAJOR CHANGE IN THE LOW LEVEL THERMAL
PROFILE...AFTERNOON HIGHS WILL STILL REACH INTO THE MID TO UPPER
80S ALONG AND WEST OF THE VALLEY.
SOME AFTERNOON SHOWERS AND THUNDERSTORMS ARE POSSIBLE IN THE LAKE
OF THE WOODS REGION ON THURSDAY...BUT ALL OTHER AREAS SHOULD BE
DRY WITH PARTLY SUNNY SKIES. IT WILL BE A BIT BREEZY FROM THE
NORTHWEST WITH BOUNDARY LAYER WIND FROM 25 TO 30 KTS TO MIX TO
THE SURFACE. HIGHS THURSDAY WILL BE FROM THE LOW TO MID 80S.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 328 AM CDT WED JUN 26 2013
500 HPA FLOW SHIFTS SHARPLY TO THE NORTHWEST BY FRIDAY WITH A
SERIES OF WEAK SHORT-WAVES MOVING THROUGH THE NORTHERN PLAINS. WILL
MAINTAIN 20 TO 40 POPS ACROSS THE NORTHEAST THIRD OF THE FORECAST
AREA...BUT DO NOT ANTICIPATE WIDESPREAD RAINS. BREEZY NORTHWEST
WIND WILL CONTINUE WITH HIGHS IN THE UPPER 70S TO LOWER 80S.
NOT MUCH TIME SPENT ON EXTENDED (SAT-EARLY NEXT WEEK) DUE TO
CURRENT FLOODING ISSUES. 00Z GFS/EURO SHOW UPPER LOW DROPPING INTO
ERN ND/NW MN SATURDAY GIVING CHANCES FOR SOME PRECIPITATION...THEN
EXITING SUNDAY. 00Z GEM IS DRIER. THEREAFTER..MODELS DIVERGE WITH
EURO EXPANDING HEAT RIDGE OVER THE ROCKIES A BIT FARTHER EAST AND
FORCING NEXT SHORT WAVE DUE MON-TUE A BIT FARTHER EAST OVER
NORTHEAST MN. 00Z GFS IS FARTHER WEST WITH RIDGE AND HAS NEXT
SHORT WAVE OVER OUR AREA MON-TUE AND HIGHER PRECIP CHANCES. KEPT
WITH ALL BLEND IDEA OF HAVING 20-30 POPS EARLY NEXT WEEK FOLLOWING
GFS SOLN. BUT CONFIDENCE IS QUITE LOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1255 PM CDT WED JUN 26 2013
SCT TO BKN MAINLY VFR CU FIELD WILL CONTINUE THROUGH THE
AFTERNOON...WITH CIGS OCCASIONALLY DROPPING INTO THE MVFR RANGE
ESPECIALLY EAST OF THE VALLEY. DID UTILIZE 15Z HRRR TO INCLUDE MOST
PROBABLE TIME PERIOD FOR CONVECTIVE ACTIVITY WITH THE PASSAGE OF A
SFC TROUGH THIS AFTERNOON/EVENING. WITH SCATTERED NATURE OF
ACTIVITY...WENT WITH VCTS FOR NOW. WEST WINDS THIS AFTERNOON WILL
SUBSIDE THIS EVENING...BEFORE INCREASING AGAIN OUT OF THE WEST TO
NORTHWEST BY MID TO LATE MORNING THURSDAY.
&&
.HYDROLOGY...
ISSUED AT 1255 PM CDT WED JUN 26 2013
ALL RIVERS AROUND FARGO ARE SEEING SHARP RISES AT THE PRESENT TIME.
IT APPEARS THAT THE RED AT FARGO WILL APPROACH MAJOR FLOOD STAGE
WITHIN THE NEXT COUPLE OF DAYS. SIMULATIONS INDICATE THAT POINTS
DOWNSTREAM OF FARGO WILL ALSO APPROACH OR EXCEED MINOR FLOOD STAGE
IN SEVERAL DAYS...FROM HALSTAD THROUGH OSLO MN. AN AREAL FLOOD
WARNING REMAINS IN EFFECT FOR WILKIN AND RICHLAND COUNTIES...AND A
FLOOD ADVISORY HAS BEEN POSTED FOR CASS COUNTY.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...TG
SHORT TERM...ROGERS
LONG TERM...ROGERS/RIDDLE
AVIATION...MAKOWSKI
HYDROLOGY...WJB
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1223 AM CDT WED JUN 26 2013
.UPDATE...
ISSUED AT 1223 AM CDT WED JUN 26 2013
UPDATE FOR THE EXPIRATION OF SEVERE THUNDERSTORM WATCH 364 ACROSS
THE JAMES RIVER VALLEY. REMAINING STORMS ACROSS DICKEY AND LAMOURE
COUNTIES ARE EXPECTED TO CLEAR THE CWA BY 06 UTC AND REMAIN BELOW
SEVERE LIMITS GIVEN WEAK DEEP LAYER SHEAR. WILL CONTINUE TO
MONITOR RAINFALL WITH THESE STORMS. HOWEVER...THEY HAVE BEEN
PROPAGATING TO THE EAST AT 20 KTS...LIMITING THE FLASH FLOOD
THREAT.
UPDATE ISSUED AT 1047 PM CDT TUE JUN 25 2013
SEVERE THUNDERSTORM WATCH HAS BEEN CANCELLED FOR ALL BUT FOSTER...
STUTSMAN...DICKEY AND LAMOURE COUNTIES. HAVE ONCE AGAIN UPDATED
FOR LATEST RADAR TRENDS...REMOVING ALL POPS BUT FOR THE REMAINING
COUNTIES IN THE SEVERE THUNDERSTORM WATCH. THIS ACTIVITY SHOULD BE
OUT OF THE CWA AROUND MIDNIGHT. WILL ALSO CANCEL THE REMAINING
COUNTIES OF THE FLASH FLOOD WATCH SHORTLY.
UPDATE ISSUED AT 849 PM CDT TUE JUN 25 2013
HAVE REMOVED ANOTHER TIER OF COUNTIES FROM THE SEVERE THUNDERSTORM
AND FLASH FLOOD WATCHES. ALSO ADJUSTED POPS BASED ON CURRENT RADAR.
OTHERWISE NO SIGNIFICANT CHANGES TO THE GOING FORECAST. UPDATED
FLASH FLOOD WATCH AND WCN PRODUCTS HAVE BEEN SENT. REMAINING
UPDATED PRODUCTS OUT SHORTLY.
UPDATE ISSUED AT 708 PM CDT TUE JUN 25 2013
CONVECTION ACROSS CENTRAL NORTH DAKOTA CONTINUES TO MOVE
NORTHEAST. WIND SHIFT HAS MOVED THROUGH NORTHWEST...INTO THE SOUTH
CENTRAL PORTION OF THE STATE. THUS HAVE DROPPED WESTERN PORTIONS
OF THE SEVERE THUNDERSTORM WATCH INCLUDING MORTON...MERCER...
OLIVER...DIVIDE AND WILLIAMS. HAVE ALSO DROPPED WESTERN PORTIONS
OF THE FLASH FLOOD WATCH. THESE UPDATES HAVE BEEN SENT.
MAIN UPDATES WERE TO ADJUST POPS TO CURRENT RADAR TRENDS. UPDATED
ZONES AND STATE WILL BE SENT SHORTLY.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 200 PM CDT TUE JUN 25 2013
FORECAST HIGHLIGHTS IN THE SHORT TERM FORECAST PERIOD WILL BE
STRONG TO SEVERE THUNDERSTORMS AND HEAVY RAIN POTENTIAL THROUGH
THIS EVENING.
CURRENTLY...WARM AND VERY HUMID DAY WITH DAYTIME HIGHS IN THE 80S
AND SURFACE DEWPOINT TEMPS FROM 60 TO THE LOW 70S. LATEST RADAR IS
VOID OF ECHOS OVER WEST AND CENTRAL NORTH DAKOTA AS OF 2 PM CDT.
LATEST MODEL GUIDANCE SUGGESTS CONVECTIVE DEVELOPMENT
NORTHWEST/NORTH CENTRAL EARLY THIS AFTERNOON...BUILDING SOUTH-
SOUTHEAST LATE AFTERNOON-EARLY EVENING ALONG A SURFACE TROUGH IN
PLACE FROM NORTHWEST NORTH DAKOTA THROUGH CENTRAL SOUTH DAKOTA.
17-18Z RAP SOUNDINGS WEAKEN/ERASE THE CAP BETWEEN 20-22Z ALONG THE
SFC TROUGH AXIS. TRIGGER WILL BE A STRONG MID LEVEL S/WV PUSHING
INTO WESTERN NORTH DAKOTA NOW...HELPING TO WEAKEN THE STRONG
CAPPING INVERSION CURRENTLY IN PLACE. CONVECTION SHOULD THEN PUSH
EAST THIS EVENING INTO THE OVERNIGHT WITH THE MID LEVEL WAVE AND
SFC TROUGH. STRONG TO SEVERE WEATHER REMAINS IN PLAY WITH THE VERY
STRONG INSTABILITY PRESENT...CURRENTLY 3-6K J/KG. LIMITING FACTOR
WILL BE RATHER WEAK 0-6KM/EFFECTIVE SHEAR UP TO AROUND 20KTS
CURRENTLY IN PLACE AND FORECAST THROUGH THIS EVENING. STILL...WITH
THE AMOUNT OF CAPE PRESENT THERE IS A GOOD PROBABILITY OF LARGE
SEVERE HAIL AND A DAMAGING WIND GUSTS. STORMS WILL BE WATER
LOADED SO WILL LIKELY NEED A RATHER ROBUST/TALL UPDRAFT TO GET THE
LARGE HAIL. IT DOES APPEAR THE MAIN THREAT TODAY INTO THIS EVENING
WILL BE VERY HEAVY RAINFALL ELEVATING THE THREAT FOR FLASH
FLOODING.
CONVECTIVE CHANCES WILL END FROM WEST TO EAST THIS EVENING THROUGH
WEDNESDAY MORNING AS FORCING PUSHES EASTWARD.
OPTED TO KEEP WEDNESDAY AFTERNOON DRY FOR NOW ALONG WITH THE 12Z
GFS/00Z ECMWF. THE 06Z AND 12Z NAM BOTH PAINTED LIGHT DIURNALLY
DRIVEN QPF...SO WILL LET LATER SHIFTS TAKE A LOOK WITH ATTENTION
FOCUSED ON THE NEXT 12 HOURS.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 200 PM CDT TUE JUN 25 2013
THE MAIN FEATURE FOR THE EXTENDED PERIOD WILL BE THE INTENSIFYING
UPPER LEVEL RIDGE OVER THE WESTERN US/CANADA AS FORECAST BY THE 12Z
MODEL SUITE. WITH THE RIDGE AXIS POSITIONED OVER THE INTERMOUNTAIN
WEST...NORTH TO NORTHWESTERLY FLOW WILL BE DOMINANT ACROSS NORTH
DAKOTA FOR MUCH OF THE PERIOD. THIS WILL ALLOW FOR SEASONABLE
TEMPERATURES...IN THE 80S TO CONTINUE...KEEPING THE AREA OUT THE
WARMEST H850 TEMPERATURES THAT WILL DEVELOP ACROSS THE WESTERN US.
OVERALL THE FORECAST WILL REMAIN DRY...HOWEVER THERE WILL BE
PERIODIC CHANCES FOR PRECIPITATION FOR PARTS OF CENTRAL AND EASTERN
NORTH DAKOTA...AS A FEW SHORTWAVES ROTATE AROUND THE WESTERN
PERIPHERY OF THE UPPER LEVEL LOW POSITIONED OVER THE GREAT LAKES
REGION. LATE THIS WEEKEND/EARLY NEXT WEEK...SOME UNCERTAINTY IS
INTRODUCED INTO THE FORECAST AS THE THERE IS SOME DISAGREEMENT
AMONGST THE 12Z LONG RANGE MODELS REGARDING THE POTENT SHORTWAVE
THAT IS PROGGED TO DROP SOUTH FROM CANADA AND INTO THE NORTHERN
PLAINS. DUE TO THIS UNCERTAINTY...WILL MAKE NO CHANGES TO THE
ALLBLEND SOLUTION AT THIS TIME SINCE THERE IS NO TARGET OF
OPPORTUNITY TO IMPROVE FORECAST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1223 AM CDT WED JUN 26 2013
VFR CONDITIONS ARE EXPECTED AT ALL TERMINALS FOR THE 06 UTC TAF
CYCLE SOUTH OF WEAK LOW PRESSURE ACROSS SOUTHERN CANADA.
&&
.HYDROLOGY...
ISSUED AT 200 PM CDT TUE JUN 25 2013
A FLASH FLOOD WATCH REMAINS IN EFFECT FOR NORTHWEST AND CENTRAL
NORTH DAKOTA THROUGH THIS EVENING. VERY SLOW MOVING THUNDERSTORMS
WITH INTENSE RAINFALL RATES ARE EXPECTED. ONE HOUR FLASH FLOOD
GUIDANCE IS AROUND ONE TO ONE AND A HALF INCHES ACROSS MOST OF THE
WATCH AREA. RAINFALL RATES WITH THUNDERSTORMS TODAY WILL EASILY
SURPASS THIS THRESHOLD...AND WILL HAVE TO CLOSELY MONITOR FOR
FLASH FLOODING THIS AFTERNOON AND EVENING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
LONG TERM...LTH
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
734 PM EDT THU JUN 27 2013
.SYNOPSIS...
UPPER LEVEL DROPS SOUTH ACROSS THE GREAT LAKES REGION INTO THE
AREA FRIDAY THROUGH THE WEEKEND. IT MAY REGRESS TO THE WEST AFTER
THAT.
&&
.NEAR TERM /THROUGH FRIDAY/...
UPDATE...
NO LARGE SCALE CHANGES TO THE FORECAST. WILL NEED TO WATCH THE
CONVECTION THIS EVENING...ESPECIALLY THAT UPSTREAM IN MICHIGAN AND
NORTHERN OHIO WORKING TO THE SOUTH SOUTHEAST. EXPECT THIS TO WEAKEN
AND DISSIPATE...ALTHOUGH THE HRRR DOES HOLD ONTO SOME REMNANTS
COMING INTO THE NORTHERN ZONES AFTER 06Z.
PREVIOUS DISCUSSION...
THE UPPER LEVEL SHORTWAVE OVER PA...WILL CONTINUE TO MOVE EAST
NORTHEAST LOOSING ITS INFLUENCE OVER WV. RADAR IMAGES SHOW THE
BULK OF THE CONVECTION IS TO OVER THE NORTHEAST QUADRANT OF THIS
SHORTWAVE. HOWEVER...LIGHT RAIN SHOWERS ARE EVIDENT ON
RADAR...DEVELOPING IN THE WEST AND SOUTH QUADRANTS ACROSS
OH...KY...TN...AND WV THIS AFTERNOON. EXPECT THESE LIGHT SHOWERS
TO CONTINUE TONIGHT. THEREFORE...KEPT CHANCE POPS THROUGH FRIDAY
MORNING.
WITH NO REAL COLD AIR PUSHING MOISTURE AWAY...HIGH SFC
DEWPOINTS...IN THE UPPER 60S WILL PERSIST THROUGH FRIDAY...
BRINGING A MUGGY NIGHT...AND LOW CLOUDS OR AREAS OF FOG TONIGHT.
BY FRIDAY AFTERNOON...A DEEP UPPER LEVEL TROUGH OVER CANADA DIGS
SOUTH ACROSS THE GREAT LAKES REGION. THE GFS AND NAM80 SHOW H5
VORT MAXES PASSING ACROSS WV BY 00Z FRIDAY. WITH ABUNDANT MOISTURE
AND A STRENGTHENING UPPER LOW OVERHEAD...EXPECT PLENTY OF CLOUDS
AND LIKELY POPS ON FRIDAY WITH THIS SECOND SYSTEM.
WENT CLOSER TO THE BIAS CORRECTED MAV NUMBERS PER HIGH DEWPOINTS
AND PLENTY OF CLOUDS THROUGH THE PERIOD.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
AMPLIFIED UPR TROF BECOMING ESTABLISHED OVER THE REGION...WITH AXIS
ACROSS OH VALLEY INTO MID MS VALLEY. HARD TO TIME IMPULSES WILL
ROTATE DOWN THRU WEEKEND. CONT WITH THE DIURNAL NATURE TO POPS SOME
BROAD HIGH CHC POPS FOR SAT. TEMPS TO COME DOWN TO MORE SEASONABLE
LEVELS.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
NOT MUCH CHANGE IN FCST REASONING IN THE EXTENDED FROM YESTERDAY.
BERMUDA HIGH REMAINING IN PLACE AND TROF AXIS SLOWLY RETROGRADING
TO MS VALLEY...UNSETTLED WX WILL BE THE RULE FOR THE WEEK. CONT
WITH DIURNAL NATURE OF POPS WITH HIGH CHC EACH AFTN...WANING WITH
AFTER SUNSET. BEST CONCENTRATION MAY END UP BEING ACROSS THE MTNS
WITH SE LLVL FLOW PROVIDING FOR EXTRA LIFT. INFLUENCE OF BROAD
DEEP S FLOW AND PWATS COMING UP TO ARND 1.75 INCHES TO ALLOW FOR
DOWNPOURS. GENERALLY FOLLOWED HPC FOR TEMPS WITH TWEAKS HERE AND
THERE. THIS ESSENTIALLY KEEPS THINGS STATUS QUO WITH SEASONAL
HIGHS AND SOMEWHAT MUGGY NIGHTS.
&&
.AVIATION /23Z THURSDAY THROUGH TUESDAY/...
ISOLATED CONVECTION SHOULD DECREASE OVER THE NEXT FEW HOURS WITH
THE END OF DAYTIME HEATING...AND KEEP ALL PREVAILING CONDITIONS
FREE FROM SH OR TS. DO USE VCTS AND VCSH IN A COUPLE OF CASES.
OTHERWISE...THE KEY TO THIS FORECAST IS THE WIND...WITH THE BULK
OF THE GUIDANCE KEEPING THE WIND UP. ONLY THE MET GUIDANCE BRINGS
CALM CONDITIONS LATER TONIGHT. RIDE THE MAJORITY VOTE HERE AND
KEEP IFR MIST/FOG OUT OF THE FORECAST WITH WIND SPEEDS OF 4-6KTS
SUSTAINED EXPECTED TONIGHT.
THOSE TERMINALS STILL IN THE MVFR CEILINGS WILL SEE IMPROVEMENTS
OVER THE NEXT FEW HOURS AS WELL.
CONVECTION POSSIBILITIES RETURN FRIDAY DURING THE AFTERNOON
HOURS...AS WILL WINDS GUSTING 15-20KTS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z SATURDAY...
FORECAST CONFIDENCE...MEDIUM.
ALTERNATE SCENARIOS: TIMING AND COVERAGE OF CONVECTION COULD VARY.
MET GUIDANCE MAY HOLD THE KEY TO THE WINDS OVERNIGHT AND
SUBSEQUENT FOG POTENTIAL.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 20 21 22 23 00 01 02 03 04 05 06 07
EDT 1HRLY 16 17 18 19 20 21 22 23 00 01 02 03
CRW CONSISTENCY L L L H M M M M M H H H
HTS CONSISTENCY H M M M M M M M H H H H
BKW CONSISTENCY L L L L L L M M M M M M
EKN CONSISTENCY H H H H M L M L L L L L
PKB CONSISTENCY H H M M M M M M M H H H
CKB CONSISTENCY H H H H L L M H H H H H
AFTER 00Z SATURDAY...
NO WIDESPREAD IFR EXPECTED AT THIS TIME.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/30
NEAR TERM...ARJ/26
SHORT TERM...30
LONG TERM...30
AVIATION...26
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
949 PM CDT THU JUN 27 2013
.UPDATE...
THE THUNDERSTORM COMPLEX THAT EXTENDS FROM NORTHEASTERN KANSAS
SOUTHWEST THROUGH CENTRAL OKLAHOMA WEST INTO THE TEXAS PANHANDLE
CONTINUES TO MOVE SOUTHWARD THIS EVENING. A DECENT OUTFLOW
BOUNDARY IS APPARENT ON THE RADAR LOOPS THIS EVENING AHEAD OF
THIS COMPLEX. THE THUNDERSTORM COMPLEX IS EXPECTED TO WEAKEN
LATER THIS EVENING AND DISSIPATE BEFORE CROSSING THE RED RIVER
OVERNIGHT. THE 18Z TEXAS TECH WRF IS NOT REPRESENTATIVE OF WHAT
IS CURRENTLY HAPPENING. THE 00Z RUN OF THE NAM WHICH SEEMS TO BE
UNDER-DOING WHAT IS CURRENTLY OCCURRING...ALSO INDICATES THAT THE
COMPLEX SHOULD DISSIPATE BEFORE REACHING THE RED RIVER. THE HIGH
RESOLUTION RAPID REFRESH AND THE RAP INDICATE THAT THE PART OF
THE SYSTEM THAT WOULD AFFECT US ON ITS CURRENT TRACK WILL ALSO
DISSIPATE BEFORE REACHING NORTH TEXAS. SOME HIGH CLOUDS FROM THIS
ACTIVITY SPREAD INTO NORTH TEXAS LATER TONIGHT. AS FAR AS
TOMORROW IS CONCERNED. IT STILL APPEARS THAT WE WILL HAVE A
PRETTY HOT DAY WITH SOUTHWESTERLY SURFACE WINDS AHEAD OF THE WEAK
COLD FRONT. WACO MAY COME CLOSE TO THEIR RECORD HIGH FOR JUNE
28TH WHICH IS 106 DEGREES SET IN 1980. THE RECORD HIGH FOR DFW
FOR TOMORROW IS AN UNATTAINABLE /WE HOPE/ 112 DEGREES WHICH ALSO
OCCURRED IN 1980.
58
&&
.AVIATION...
AS WEAK FRONT PUSHES INTO THE AREA TOMORROW...WINDS WILL VEER TO
THE WSW. THE FRONT AND ACCOMPANYING NORTH WINDS WILL NOT REACH
THE METROPLEX TAF SITES UNTIL LATE AFTERNOON. ALTHOUGH THERE IS
LITTLE UPPER SUPPORT...THE LIFT ALONG THE FRONT MAY PRODUCE
ISOLATED TSRA GIVEN THAT HIGH TEMPERATURES ARE EXPECTED TO BE IN
THE TRIPLE DIGITS. AT THIS TIME TS PROBABILITIES LOOK TOO LOW TO
MENTION...BUT MAY HAVE TO INCLUDE IN LATER TAFS IF THIS EVENING/S
HI RES MODELS BECOME WETTER.
AT WACO...WINDS WILL ALSO VEER BUT FRONT WILL NOT REACH THERE
UNTIL AFTER THIS TAF/S VALID TIME. 84
&&
.PREV DISCUSSION... /ISSUED 343 PM CDT THU JUN 27 2013/
CHANGES ARE ON THE WAY FOR NORTH AND CENTRAL TEXAS BEGINNING
TOMORROW. THROUGH THE WEEKEND...THE UPPER LEVEL RIDGE THAT HAS
BEEN DOMINATING THE AREA WILL AMPLIFY OVER THE WESTERN CONUS
WHILE AN UPPER LEVEL TROUGH DIGS DEEP OVER THE EASTERN HALF OF THE
COUNTRY. THE INFLUENCE OF THE UPPER LEVEL RIDGE WILL GREATLY BE
WEAKENED FROM THE DEEPENING TROUGH TO OUR EAST. OVERALL...THIS
WILL RESULT IN COOLER TEMPERATURES AND SLIGHT CHANCES FOR RAIN
OVER THE NEXT WEEK.
EXPECT ANOTHER MOSTLY CLEAR AND WARM NIGHT TONIGHT WITH OVERNIGHT
LOWS IN THE MID TO UPPER 70S...EXCEPT LOWER 80S IN THE DALLAS CITY
AREA. FRIDAY IS EXPECTED TO BE AN OPPRESSIVELY HOT DAY ACROSS PART
OF THE REGION DUE TO A COOL FRONT MOVING INTO THE AREA. THIS FRONT
WILL BE THE FIRST OF TWO THAT INFLUENCES NORTH AND CENTRAL TEXAS THIS
WEEKEND. SHARPLY WARMING TEMPERATURES ARE EXPECTED AHEAD OF
TOMORROWS FRONT WITH TEMPERATURES SOARING BETWEEN 101-107 AHEAD OF
THE FRONT. THE CHALLENGE IS THE SPEED AND TIMING OF THE FRONT. THE
LOCATION OF THE FRONT WILL DETERMINE WHERE THE HOTTEST
TEMPERATURES WILL OCCUR TOMORROW. MOST OF THE MODELS /INCLUDING
SHORTER TERM HI-RES MODELS/ HAVE THE FRONT AROUND THE I-20
CORRIDOR ABOUT MID AFTERNOON TOMORROW. BASED ON THIS
TIMING/LOCATION...KEPT HIGH TEMPERATURES NORTH OF I-20 IN THE MID
TO UPPER 90S...CLOSE TO 100-101 NEAR THE I-20 CORRIDOR...AND THEN
RANGING FROM 103-107 SOUTH OF THE I-20 CORRIDOR. IN
ADDITION...ALSO INTRODUCED A MENTION OF ISOLATED THUNDERSTORMS
OVER THE NORTHERN TWO-THIRDS OF THE REGION FRIDAY AFTERNOON AS
SOME MODELS INDICATE ISOLATED CONVECTION MAY DEVELOP ALONG AND
SLIGHTLY AHEAD OF THE FRONT. HOWEVER...FORECAST SOUNDINGS INDICATE
THE LOWER LEVELS OF THE ATMOSPHERE WILL BE PRETTY DRY. THIS POINTS
TO THE POTENTIAL FOR LOTS OF EVAPORATION/VIRGA FROM MID LEVEL
CLOUDS/CONVECTION AND ALSO A THREAT FOR GUSTY WINDS WITH ANY
CONVECTION THAT DOES MATERIALIZE.
BEHIND TOMORROWS COOL FRONT...DRIER AIR WILL BEGIN TO FILTER INTO
THE REGION WITH A BETTER PUSH OF DRY AIR ON SUNDAY BEHIND THE NEXT
FRONT/REINFORCING FRONT. TEMPERATURES ON SATURDAY WILL STILL BE
WARM RANGING FROM THE LOWER 90S IN THE NORTHEAST TO UPPER 90S/NEAR
100 DEGREES IN THE WEST AND SOUTHWEST. TEMPERATURES WILL FINALLY
START TO DROP SATURDAY NIGHT AND THE REMAINDER OF THE FORECAST
LOOKS TO BE GENERALLY BELOW NORMAL. THE LATEST SET OF MODEL RUNS
INDICATE THAT THE AIR BEHIND SUNDAY/S FRONT WILL BE DRIER THAN
PREVIOUS MODEL RUNS...WITH DEWPOINTS IN THE 50S AND LOWER 60S
THROUGH AT LEAST MID WEEK. THIS WILL RESULT IN LOWER OVERNIGHT
LOWS AND ALSO MORE PLEASANT DAYTIME HIGHS FOR THIS TIME OF YEAR. IN
SUMMARY...OVERNIGHT LOWS WILL MOSTLY BE IN THE 60S AND
OCCASIONALLY LOWER 70S...DAYTIME HIGHS WILL BE IN THE MID 80S TO
LOWER 90S. IT IS ALSO GOING TO FEEL MUCH DRIER WITH LOWER HUMIDITY
VALUES THANKS TO THE LOWER DEWPOINT TEMPERATURES.
WHILE THERE ARE SOME CHANCES FOR RAIN THROUGH THE FORECAST
PERIOD...THE BEST CHANCES FOR RAIN MAY ACTUALLY COME NEAR THE END
OF THE FORECAST...NEAR THE JULY 4TH HOLIDAY. HAVE TAPERED BACK THE
POPS FOR SATURDAY AS IT LOOKS LIKE THE RIDGE WILL HOLD STRONG OVER
OUR WESTERN COUNTIES. THERE ARE STILL SLIGHT CHANCES FOR RAIN
OVER THE REGION ON SUNDAY AS THE NEXT FRONT ARRIVES. WITH THE
DRIER AIR EXPECTED BEHIND SUNDAY/S FRONT...RAIN CHANCES EARLY NEXT
WEEK ARE SLIM BUT NOT COMPLETELY ZERO. WE WILL BE UNDER THE
INFLUENCE OF NORTHERLY FLOW ALOFT BETWEEN THE UPPER TROUGH TO OUR
EAST AND THE RIDGE TO OUR WEST. HOWEVER...IT/S DIFFICULT TO PIN
POINT EXACTLY WHEN AND WHERE ISOLATED CONVECTION WILL OCCUR THIS
PATTERN AND KEPT GHOST 10 POPS IN THE FORECAST. WE COULD HAVE
ISOLATED AFTERNOON CONVECTION NEAR OR IN OUR FAR EASTERN
ZONES...CLOSER TO THE UPPER LEVEL TROUGH. BY THE MIDDLE TO END OF
NEXT WEEK...THE UPPER LEVEL TROUGH TO OUR EAST WILL EXPAND FARTHER
WEST AND WE COULD SEE SOME DISTURBANCES CROSSING THE REGION.
INTRODUCED 20 POPS FOR NOW ON WEDNESDAY AND THURSDAY OF NEXT WEEK.
82/JLD
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 78 102 76 98 72 / 0 10 5 10 10
WACO, TX 76 104 75 99 71 / 0 10 10 10 10
PARIS, TX 74 97 71 92 66 / 5 10 5 10 10
DENTON, TX 76 99 73 97 69 / 5 10 5 10 10
MCKINNEY, TX 75 99 72 96 69 / 0 10 5 10 10
DALLAS, TX 81 102 77 98 74 / 0 10 5 10 10
TERRELL, TX 76 101 74 96 70 / 0 10 5 10 10
CORSICANA, TX 76 105 75 98 71 / 0 10 10 10 10
TEMPLE, TX 74 103 75 99 71 / 0 10 10 10 10
MINERAL WELLS, TX 77 103 73 98 69 / 0 10 5 10 10
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
84/58
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1049 PM CDT THU JUN 27 2013
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.UPDATE...
ISSUED AT 902 PM CDT THU JUN 27 2013
HAVE UPDATED PCPN TRENDS FOR THE REST OF THE NIGHT. ALTHOUGH THE
CONVECTION HAS WEAKENED...POCKETS OF HEAVY RAINFALL WILL CONTINUE
FOR AT LEAST A FEW MORE HOURS. FOR THE OVERNIGHT PERIOD...EXPECT
SCT SHRA/ISOLD TSTMS...AS S/W TROFS CONTINUE TO SLIDE SE INTO
THE FCST AREA. POPS WILL CONTINUE TO BE LOWEST OVER CENTRAL WI...
ALTHOUGH ISOLD CONVECTION STILL LOOKS PSBL THERE.
&&
.SHORT TERM...TONIGHT AND FRIDAY
ISSUED AT 331 PM CDT THU JUN 27 2013
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A 100KT JET
STREAK DIVING INTO THE WESTERN GREAT LAKES AS THE SOUTHWEST SUB-
TROPICAL RIDGE BUILDS NORTHWARD. VARIOUS SHORTWAVE IMPULSES FROM
SOUTHERN MANITOBA TO THE UPPER PENINSULA COMBINED WITH INCREASING
INSTABILITY AROUND 1500 J/KG ARE TRIGGERING SCATTER SHOWERS AND
THUNDERSTORMS. MANY STORMS HAVE BEEN FLIRTING WITH SEVERE
LEVELS...WHICH SHOULD CONTINUE THROUGH EARLY THIS EVENING. PRIMARY
UPPER TROUGH OVER SOUTHEAST MANITOBA WILL BE DROPPING INTO THE
REGION TOMORROW. THE MAIN FORECAST CONCERNS REVOLVE AROUND SEVERE
WEATHER FOR THE REST OF TODAY AND PRECIP TOMORROW.
TONIGHT...CHANNELED VORTS ON THE CYCLONIC SHEAR SIDE OF THE UPPER
JET WILL BE DIVING SOUTHEAST THIS EVENING ACROSS NORTHERN
WISCONSIN. AMPLE INSTABILITY AROUND 1.5K J/KG COMBINED WITH THIS
FORCING ALOFT SHOULD BE ABLE TO SUSTAIN STORMS INTO EASTERN
WISCONSIN LATER THIS AFTERNOON AND THIS EVENING. AS THE JET STREAK
SHIFTS A LITTLE SOUTH AND THE UPPER LOW MOVES OVER LAKE
SUPERIOR...0-6KM BULK SHEAR VALUES WILL BE DROPPING THIS EVENING.
COMBINED WITH LOSS OF INSTABILITY...SHOULD SEE STORMS DIMINISH IN
INTENSITY BY MID EVENING. STILL SOME SHOWERS COULD POP UP THROUGH
THE NIGHT OVER NORTH-CENTRAL TO NORTH-EAST WISCONSIN AND WILL LEAVE
SMALL POPS IN THE FORECAST FOR THE REST OF THE NIGHT. LOWS IN THE
50S AND 60S.
FRIDAY...THE UPPER LOW OVER LAKE SUPERIOR WILL DROP SOUTHEAST ACROSS
THE CENTRAL GREAT LAKES. AS THIS OCCURS...A DEEP TROUGH WILL DROP
ACROSS THE STATE WHICH SHOULD BRING SHOWERS AND STORMS TO NORTHERN
WISCONSIN DURING THE MORNING. ADDITIONAL STORMS ARE LIKELY IN THE
AFTERNOON WITH HELP FROM DIURNAL INSTABILITY. WITH THE CLOUD COVER
AND COOLER TEMPS...NOT ANTICIPATING ANY SEVERE STORMS AT THIS TIME.
A MOSTLY CLOUDY DAY WITH HIGHS IN THE UPPER 60S TO MID 70S.
.LONG TERM...FRIDAY NIGHT THROUGH THURSDAY
ISSUED AT 331 PM CDT THU JUN 27 2013
FOR THE EARLY PORTION OR THROUGH
SATURDAY...CONVECTION WILL MAINLY BE ASSOCIATED WITH THE SOUTHWARD
PASSAGE OF THE TROUGH AXIS. PCPN WILL BE ON THE DECREASE FROM
NORTH TO SOUTH ON SATURDAY AS HIGH PRESSURE BUILDS IN FROM THE NORTH.
COOLER DRIER AIR WILL FILTER INTO THE STATE ON NORTH WINDS AS A
LARGE HIGH PRESSURE SYSTEM SETTLES INTO THE NORTHERN PLAINS AND
GREAT LAKES REGION. PROBLEM OR CHALLENGE WITH THE LATER PERIODS
CONCERN ORIENTATION OF THE RETROGRADING DEEP UPPER TROUGH OR UPPER
LOW OVER THE SURFACE HIGH PRESSURE. H5 TEMPS PROGGED TO BE ONLY IN
THE -12 C RANGE ABOVE THE SURFACE HIGH...SO NOT REALLY A COOL AIR
MASS ALOFT TO SUPPORT INSTABILITY AFTERNOON PCPN...SO WILL LEAVE
THE SHOWER MENTION OUT OF THE LATER PERIODS FOR NOW...BUT CANNOT
RULE OUT VERY ISOLATED SHOWER ACTIVITY.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1043 PM CDT THU JUN 27 2013
SEVERAL UPPER LEVEL DISTURBANCES WILL TRACK THROUGH THE AREA
OVERNIGHT INTO FRIDAY...AND EACH WILL LIKELY RESULT IN SHRA/ISOLD
TSRA DEVELOPMENT. PATCHY MVFR/IFR CONDITIONS ARE EXPECTED LATE
TONIGHT...WITH FOG AND ISOLD TSTMS. MORE WIDESPREAD MVFR CIGS ARE
EXPECTED TO DEVELOP ACROSS THE FORECAST AREA ON FRIDAY...AND SCT
TSTMS ARE EXPECTED DURING THE AFTERNOON. COOLER NORTH WINDS AND
ABUNDANT LOW-LEVEL MOISTURE MAY RESULT IN SOME IFR CIGS BY MID TO
LATE FRIDAY EVENING.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE.........KIECKBUSCH
SHORT TERM.....MPC
LONG TERM......TDH
AVIATION.......KIECKBUSCH
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
906 PM CDT THU JUN 27 2013
NEW INFORMATION ADDED TO UPDATE SECTION
.UPDATE...
ISSUED AT 902 PM CDT THU JUN 27 2013
HAVE UPDATED PCPN TRENDS FOR THE REST OF THE NIGHT. ALTHOUGH THE
CONVECTION HAS WEAKENED...POCKETS OF HEAVY RAINFALL WILL CONTINUE
FOR AT LEAST A FEW MORE HOURS. FOR THE OVERNIGHT PERIOD...EXPECT
SCT SHRA/ISOLD TSTMS...AS S/W TROFS CONTINUE TO SLIDE SE INTO
THE FCST AREA. POPS WILL CONTINUE TO BE LOWEST OVER CENTRAL WI...
ALTHOUGH ISOLD CONVECTION STILL LOOKS PSBL THERE.
&&
.SHORT TERM...TONIGHT AND FRIDAY
ISSUED AT 331 PM CDT THU JUN 27 2013
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A 100KT JET
STREAK DIVING INTO THE WESTERN GREAT LAKES AS THE SOUTHWEST SUB-
TROPICAL RIDGE BUILDS NORTHWARD. VARIOUS SHORTWAVE IMPULSES FROM
SOUTHERN MANITOBA TO THE UPPER PENINSULA COMBINED WITH INCREASING
INSTABILITY AROUND 1500 J/KG ARE TRIGGERING SCATTER SHOWERS AND
THUNDERSTORMS. MANY STORMS HAVE BEEN FLIRTING WITH SEVERE
LEVELS...WHICH SHOULD CONTINUE THROUGH EARLY THIS EVENING. PRIMARY
UPPER TROUGH OVER SOUTHEAST MANITOBA WILL BE DROPPING INTO THE
REGION TOMORROW. THE MAIN FORECAST CONCERNS REVOLVE AROUND SEVERE
WEATHER FOR THE REST OF TODAY AND PRECIP TOMORROW.
TONIGHT...CHANNELED VORTS ON THE CYCLONIC SHEAR SIDE OF THE UPPER
JET WILL BE DIVING SOUTHEAST THIS EVENING ACROSS NORTHERN
WISCONSIN. AMPLE INSTABILITY AROUND 1.5K J/KG COMBINED WITH THIS
FORCING ALOFT SHOULD BE ABLE TO SUSTAIN STORMS INTO EASTERN
WISCONSIN LATER THIS AFTERNOON AND THIS EVENING. AS THE JET STREAK
SHIFTS A LITTLE SOUTH AND THE UPPER LOW MOVES OVER LAKE
SUPERIOR...0-6KM BULK SHEAR VALUES WILL BE DROPPING THIS EVENING.
COMBINED WITH LOSS OF INSTABILITY...SHOULD SEE STORMS DIMINISH IN
INTENSITY BY MID EVENING. STILL SOME SHOWERS COULD POP UP THROUGH
THE NIGHT OVER NORTH-CENTRAL TO NORTH-EAST WISCONSIN AND WILL LEAVE
SMALL POPS IN THE FORECAST FOR THE REST OF THE NIGHT. LOWS IN THE
50S AND 60S.
FRIDAY...THE UPPER LOW OVER LAKE SUPERIOR WILL DROP SOUTHEAST ACROSS
THE CENTRAL GREAT LAKES. AS THIS OCCURS...A DEEP TROUGH WILL DROP
ACROSS THE STATE WHICH SHOULD BRING SHOWERS AND STORMS TO NORTHERN
WISCONSIN DURING THE MORNING. ADDITIONAL STORMS ARE LIKELY IN THE
AFTERNOON WITH HELP FROM DIURNAL INSTABILITY. WITH THE CLOUD COVER
AND COOLER TEMPS...NOT ANTICIPATING ANY SEVERE STORMS AT THIS TIME.
A MOSTLY CLOUDY DAY WITH HIGHS IN THE UPPER 60S TO MID 70S.
.LONG TERM...FRIDAY NIGHT THROUGH THURSDAY
ISSUED AT 331 PM CDT THU JUN 27 2013
FOR THE EARLY PORTION OR THROUGH
SATURDAY...CONVECTION WILL MAINLY BE ASSOCIATED WITH THE SOUTHWARD
PASSAGE OF THE TROUGH AXIS. PCPN WILL BE ON THE DECREASE FROM
NORTH TO SOUTH ON SATURDAY AS HIGH PRESSURE BUILDS IN FROM THE NORTH.
COOLER DRIER AIR WILL FILTER INTO THE STATE ON NORTH WINDS AS A
LARGE HIGH PRESSURE SYSTEM SETTLES INTO THE NORTHERN PLAINS AND
GREAT LAKES REGION. PROBLEM OR CHALLENGE WITH THE LATER PERIODS
CONCERN ORIENTATION OF THE RETROGRADING DEEP UPPER TROUGH OR UPPER
LOW OVER THE SURFACE HIGH PRESSURE. H5 TEMPS PROGGED TO BE ONLY IN
THE -12 C RANGE ABOVE THE SURFACE HIGH...SO NOT REALLY A COOL AIR
MASS ALOFT TO SUPPORT INSTABILITY AFTERNOON PCPN...SO WILL LEAVE
THE SHOWER MENTION OUT OF THE LATER PERIODS FOR NOW...BUT CANNOT
RULE OUT VERY ISOLATED SHOWER ACTIVITY.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 645 PM CDT THU JUN 27 2013
SEVERAL UPPER LEVEL DISTURBANCES WILL TRACK THROUGH THE AREA
TONIGHT INTO FRIDAY...AND EACH WILL LIKELY RESULT IN SHRA/TSRA
DEVELOPMENT. THE MOST FAVORABLE PERIODS WILL BE EARLY TO MID
EVENING TONIGHT...THEN AGAIN LATE MORNING INTO THE AFTERNOON ON
FRIDAY. MVFR/IFR CONDITIONS MAY ACCOMPANY ANY TSTMS. SOME LOW
CLOUDS MAY DROP INTO NORTHERN WI LATE TONIGHT...AND AFFECT THE
RHI TAF SITE. MORE WIDESPREAD MVFR CIGS ARE EXPECTED TO DEVELOP
ACROSS THE ENTIRE FORECAST AREA ON FRIDAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE.........KIECKBUSCH
SHORT TERM.....MPC
LONG TERM......TDH
AVIATION.......KIECKBUSCH
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
649 PM CDT THU JUN 27 2013
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND FRIDAY
ISSUED AT 331 PM CDT THU JUN 27 2013
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A 100KT JET
STREAK DIVING INTO THE WESTERN GREAT LAKES AS THE SOUTHWEST SUB-
TROPICAL RIDGE BUILDS NORTHWARD. VARIOUS SHORTWAVE IMPULSES FROM
SOUTHERN MANITOBA TO THE UPPER PENINSULA COMBINED WITH INCREASING
INSTABILITY AROUND 1500 J/KG ARE TRIGGERING SCATTER SHOWERS AND
THUNDERSTORMS. MANY STORMS HAVE BEEN FLIRTING WITH SEVERE
LEVELS...WHICH SHOULD CONTINUE THROUGH EARLY THIS EVENING. PRIMARY
UPPER TROUGH OVER SOUTHEAST MANITOBA WILL BE DROPPING INTO THE
REGION TOMORROW. THE MAIN FORECAST CONCERNS REVOLVE AROUND SEVERE
WEATHER FOR THE REST OF TODAY AND PRECIP TOMORROW.
TONIGHT...CHANNELED VORTS ON THE CYCLONIC SHEAR SIDE OF THE UPPER
JET WILL BE DIVING SOUTHEAST THIS EVENING ACROSS NORTHERN
WISCONSIN. AMPLE INSTABILITY AROUND 1.5K J/KG COMBINED WITH THIS
FORCING ALOFT SHOULD BE ABLE TO SUSTAIN STORMS INTO EASTERN
WISCONSIN LATER THIS AFTERNOON AND THIS EVENING. AS THE JET STREAK
SHIFTS A LITTLE SOUTH AND THE UPPER LOW MOVES OVER LAKE
SUPERIOR...0-6KM BULK SHEAR VALUES WILL BE DROPPING THIS EVENING.
COMBINED WITH LOSS OF INSTABILITY...SHOULD SEE STORMS DIMINISH IN
INTENSITY BY MID EVENING. STILL SOME SHOWERS COULD POP UP THROUGH
THE NIGHT OVER NORTH-CENTRAL TO NORTH-EAST WISCONSIN AND WILL LEAVE
SMALL POPS IN THE FORECAST FOR THE REST OF THE NIGHT. LOWS IN THE
50S AND 60S.
FRIDAY...THE UPPER LOW OVER LAKE SUPERIOR WILL DROP SOUTHEAST ACROSS
THE CENTRAL GREAT LAKES. AS THIS OCCURS...A DEEP TROUGH WILL DROP
ACROSS THE STATE WHICH SHOULD BRING SHOWERS AND STORMS TO NORTHERN
WISCONSIN DURING THE MORNING. ADDITIONAL STORMS ARE LIKELY IN THE
AFTERNOON WITH HELP FROM DIURNAL INSTABILITY. WITH THE CLOUD COVER
AND COOLER TEMPS...NOT ANTICIPATING ANY SEVERE STORMS AT THIS TIME.
A MOSTLY CLOUDY DAY WITH HIGHS IN THE UPPER 60S TO MID 70S.
.LONG TERM...FRIDAY NIGHT THROUGH THURSDAY
ISSUED AT 331 PM CDT THU JUN 27 2013
FOR THE EARLY PORTION OR THROUGH
SATURDAY...CONVECTION WILL MAINLY BE ASSOCIATED WITH THE SOUTHWARD
PASSAGE OF THE TROUGH AXIS. PCPN WILL BE ON THE DECREASE FROM
NORTH TO SOUTH ON SATURDAY AS HIGH PRESSURE BUILDS IN FROM THE NORTH.
COOLER DRIER AIR WILL FILTER INTO THE STATE ON NORTH WINDS AS A
LARGE HIGH PRESSURE SYSTEM SETTLES INTO THE NORTHERN PLAINS AND
GREAT LAKES REGION. PROBLEM OR CHALLENGE WITH THE LATER PERIODS
CONCERN ORIENTATION OF THE RETROGRADING DEEP UPPER TROUGH OR UPPER
LOW OVER THE SURFACE HIGH PRESSURE. H5 TEMPS PROGGED TO BE ONLY IN
THE -12 C RANGE ABOVE THE SURFACE HIGH...SO NOT REALLY A COOL AIR
MASS ALOFT TO SUPPORT INSTABILITY AFTERNOON PCPN...SO WILL LEAVE
THE SHOWER MENTION OUT OF THE LATER PERIODS FOR NOW...BUT CANNOT
RULE OUT VERY ISOLATED SHOWER ACTIVITY.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 645 PM CDT THU JUN 27 2013
SEVERAL UPPER LEVEL DISTURBANCES WILL TRACK THROUGH THE AREA
TONIGHT INTO FRIDAY...AND EACH WILL LIKELY RESULT IN SHRA/TSRA
DEVELOPMENT. THE MOST FAVORABLE PERIODS WILL BE EARLY TO MID
EVENING TONIGHT...THEN AGAIN LATE MORNING INTO THE AFTERNOON ON
FRIDAY. MVFR/IFR CONDITIONS MAY ACCOMPANY ANY TSTMS. SOME LOW
CLOUDS MAY DROP INTO NORTHERN WI LATE TONIGHT...AND AFFECT THE
RHI TAF SITE. MORE WIDESPREAD MVFR CIGS ARE EXPECTED TO DEVELOP
ACROSS THE ENTIRE FORECAST AREA ON FRIDAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......TDH
AVIATION.......KIECKBUSCH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
231 PM CDT WED JUN 26 2013
.SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT)
ISSUED AT 231 PM CDT WED JUN 26 2013
SURFACE MAP THIS AFTERNOON HAS A COLD FRONT MOVING EAST ACROSS
EASTERN MN/IA. RADAR SHOWING A BROKEN LINE OF THUNDERSTORMS //SOME
FAIRLY INTENSE TO SEVERE AT TIMES// EXTENDING N-S ALONG THIS FRONTAL
BOUNDARY. LITTLE 0-3KM BULK SHEAR NOTED SO MOST OF THESE STORMS ARE
PULSE-TYPE IN NATURE WITH HIGHER-END RAP 0-1KM ML MUCAPE IN THE
3500-4200J/KG RANGE. THIS UNSTABLE AIR IS BEING PRODUCED BY
TEMPERATURES ACROSS THE AREA IN THE 80-85 DEGREE RANGE AND DEW
POINTS IN THE LOWER 70S.
LOOK FOR THIS FRONT TO SLIP EAST INTO CENTRAL WI THIS EVENING...
DRAGGING THE BULK OF THE SHOWERS/THUNDERSTORMS WITH IT. WITH
PRECIPITABLE WATER VALUES STILL SITTING IN THE 1.5-1.8 INCH
RANGE...ANY SHOWER/THUNDERSTORM EARLY THIS EVENING WILL BE CAPABLE
OF TORRENTIAL DOWNPOURS WITH SOME LOCALIZED PONDING OF WATER
POSSIBLE...ESPECIALLY ACROSS AREAS THAT RECEIVED PREVIOUS HEAVY RAIN
AND HAVE ALREADY SATURATED SOILS.
INTRODUCED A SLIGHT CHANCE OF SHOWER/THUNDERSTORMS MAINLY NORTH OF
I-94 LATER OVERNIGHT//AFTER 09Z// AS A MID-LEVEL TROUGH AND LEFT
EXIT REGION OF 75-100KT 300MB JET PUSHES INTO THIS AREA. MOST OF
THIS ACTIVITY LOOKS ELEVATED/ACCAS TYPE IN NATURE. BUFKIT SHOWS
DRYING IN THE LOWER LEVELS...SO NOT CONFIDENT ON HOW MUCH RAINFALL
WILL ACTUALLY REACH THE SURFACE. THEREFORE...WILL KEEP POPS ON THE
LOW SIDE FOR NOW. THIS MID-LEVEL WAVE CONTINUES TO MOVE ACROSS THE
AREA ON THURSDAY FOR A CONTINUED CHANCE OF SHOWERS AND
THUNDERSTORMS...MAINLY ALONG AND EAST OF THE MISSISSIPPI RIVER. MAY
HAVE TO WATCH THIS CONVECTION CLOSELY FOR SEVERE WIND/HAIL THREAT
GIVEN STEEPER LAPSE RATES AND 0-6KM BULK SHEAR IN THE 35-45KT RANGE.
THE GFS... WHICH IS THE DRIEST OF THE MODELS AS FAR AS
DEWPOINTS...YIELDS 0-1KM MLCAPE IN THE 1000-1500J/KG RANGE. IN
ADDITION...MAY HAVE SOME ADDED LIFT DUE TO THE LEFT EXIT REGION OF
75-100KT 300MB JET. OTHERWISE...LOOKING FOR A HIGH IN THE
LOWER/MIDDLE 80S WITH DEW POINTS IN THE MIDDLE 60S.
LOOK FOR THE MID-LEVEL WAVE TO EXIT EAST OF THE REGION BY LATE
THURSDAY EVENING...END THE THUNDERSTORM THREAT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 231 PM CDT WED JUN 26 2013
ON FRIDAY...MODELS IN GOOD AGREEMENT IN SWINGING A MID-LEVEL TROUGH
SOUTHWESTWARD INTO THE AREA FROM THE GREAT LAKES REGION. STEEPENING
LAPSE RATES WITH ASSOCIATED COLDER CYCLONIC FLOW ALOFT EXPECTED TO
PRODUCE SCATTERED TO NUMEROUS SHOWERS AND ISOLATED THUNDERSTORMS
MAINLY EAST OF THE MISSISSIPPI RIVER. OTHERWISE...PLAN ON HIGHS
COOLING SOMEWHAT INTO THE MID 70S TO AROUND 80 WITH FAIRLY BREEZY
NORTHWEST WINDS IN THE 10-20 MPH RANGE.
LOOK FOR COOLER CONDITIONS WITH SCATTERED SHOWERS AND ISOLATED
THUNDERSTORM ACTIVITY TO CONTINUE FRIDAY NIGHT THROUGH SATURDAY AS
THE MID-LEVEL TROUGH SWINGS SOUTH THROUGH THE AREA. HIGHS ON
SATURDAY WILL ACTUALLY SLIP SLIGHTLY BELOW NORMAL LEVELS IN THE
LOW-MID 70S. APPEARS SHOWERS WILL BE EXITING THE AREA COMPLETELY BY
SATURDAY EVENING AS THE TROUGH SHIFTS SOUTHEAST TOWARD THE OHIO
RIVER VALLEY AND RIDGING BUILDS IN FROM THE NORTHWEST.
FOR SUNDAY THROUGH WEDNESDAY...PLAN ON COOLER/OVERALL DRIER
CONDITIONS AS A MAJOR MID-LEVEL TROUGH ESTABLISHES ITSELF OVER THE
CENTRAL CONUS WITH A HIGHLY AMPLIFIED RIDGE ACROSS THE WESTERN
CONUS. EC REMAINS DRY DESPITE COOLER CYCLONIC FLOW AND THE GFS IS
LIGHT AND SPOTTY WITH ITS QPF. LOOKS LIKE MAINLY SOME DAYTIME
CUMULUS BUT REMAINING DRY. OTHERWISE...HIGHS ARE EXPECTED TO BE IN
THE 75-80 DEGREE RANGE WITH OVERNIGHT LOWS MAINLY IN THE 50S...VERY
PLEASANT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1230 PM CDT WED JUN 26 2013
A SFC THRU 700MB TROUGH AXIS WAS MOVING EAST ACROSS MN EARLY THIS
AFTERNOON. AHEAD OF THIS TROUGH SOME SCT-BKN DECKS OF MVFR STRATO-CU
HAD SPREAD ACROSS SOUTHEAST MN/WESTERN WI. THESE WILL SLOWLY RAISE
WITH DIURNAL WARMING/MIXING THIS AFTERNOON...BUT PERSIST UNTIL THE
TROUGH AXIS PASSES. A SCT-BKN LINE OF SHRA/TSRA IS EXPECTED TO
DEVELOP ALONG THIS TROUGH AS IT MOVES ACROSS THE AREA...BUT SO FAR
WEST OF THE FCST AREA IT HAS BEEN QUIET. WILL LEAVE TSRA MENTION IN
TAFS THIS AFTERNOON AS VCTS/CB UNTIL CONVECTION STARTS TO DEVELOP.
IF A LINE OF SHRA/TSRA DOES DEVELOP...PLAN ON AN UPDATE OR TWO FOR 1
TO 2 HRS OF TSRA AS THE LINE PUSHES EAST ACROSS THE TAF SITES.
ONCE THE TROUGH PASSES...DRIER AIR WILL START TO SPREAD ACROSS THE
AREA WITH THE LOWER LEVEL WIND FLOW BECOMING WEST AND NORTHWEST.
ENOUGH GRADIENT WIND EXPECTED TONIGHT TO KEEP BR/FG TO A MINIMUM...
THOUGH SOME SPOTTY BR/FG POSSIBLE IN THE MS/WI RIVER VALLEYS. ONLY
MENTIONED A SHORT PERIOD OF BCFG AROUND SUNRISE AT KLSE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...RRS
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND THURSDAY
ISSUED AT 225 PM CDT WED JUN 26 2013
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW AN ELONGATED
SHORTWAVE TROUGH SPINNING OVER THE LAKE WINNIPEG REGION WHICH ALSO
EXTENDS SOUTH INTO THE NORTHERN MISSISSIPPI VALLEY. ANOTHER
SHORTWAVE IS SPINNING OVER NORTHERN ILLINOIS AND IS HEADING
EAST...SO NOT MUCH IMPACT ACROSS OUR AREA. STORMS FIRED UP AROUND
MIDDAY ALONG A SURFACE TROUGH OVER THE WI/MN BORDER WHERE ML CAPES
ARE REACHING UP TO 2K J/KG. THE FIRST WARNING THIS AFTERNOON WAS
JUST ISSUED A FEW MINUTES AGO...BUT STORMS ARE NOT SHOWING MUCH
ORGANIZATION AND 0-6KM BULK SHEAR VALUES ARE RATHER POOR AT AROUND
20 KTS. WITH SUCH WEAK BULK SHEAR VALUES...THINKING PULSY SEVERE
AT THIS TIME UNLESS STORMS CAN BECOME MORE ORGANIZED. A FEW SPOTTY
SHOWERS TRIED TO DEVELOP OVER NORTH-CENTRAL AND FAR NORTHEAST
WISCONSIN...BUT FIZZLED OUT. SEVERE WEATHER CHANCES ARE THE MAIN
FORECAST CONCERN.
TONIGHT...LATEST TIMING HAS STORMS ARRIVING INTO NORTH-CENTRAL
WISCONSIN AT AROUND 21Z AND PROGRESSING EAST TO NORTHEAST WISCONSIN
BY 00-01Z BEFORE EXITING AFTER 04Z. WITH STORMS ARRIVING AT OR NEAR
PEAK HEATING...SEVERE WEATHER HAS POTENTIAL TO REACH NORTHEAST
WISCONSIN THOUGH CAPES ARE NOT NEARLY AS IMPRESSIVE OVER NORTHEAST
AND EAST-CENTRAL WISCONSIN AS FURTHER WEST. WITH LOSS OF HEATING
AND WEAKER INSTABILITY...THINK SEVERE THREAT OVER THE EASTERN PARTS
OF THE STATE ARE VERY MARGINAL. BETTER CHANCES WILL BE OVER
NORTH-CENTRAL WISCONSIN. ONCE THE STORMS DEPARTS/WEAKEN...RATHER
JUICY AIRMASS WILL LINGER FOR THE REST OF THE NIGHT. AREAS THAT
RECEIVED RAIN WILL BE PRIME CANDIDATES FOR DENSE FOG AND WILL ADD
FOG TO THE FORECAST. LOWS MAINLY IN THE LOW TO MID 60S.
THURSDAY...THE UPPER TROUGH OVER LAKE WINNIPEG WILL SLIDE SOUTHEAST
INTO LAKE SUPERIOR. WILL HAVE SUPPORT IN THE FORM OF UPPER
DIVERGENCE IN THE LEFT FRONT QUAD OF THE JET STREAK FOR MUCH OF THE
DAY...SO CANNOT RULE OUT SPOTTY SHOWERS AND STORMS IN THE MORNING.
BUT THINKING STORMS ARE LIKELY FOR MOST OF NORTH-CENTRAL AND
NORTHEAST WISCONSIN IN THE AFTERNOON...ONCE UPWARDS OF 1500 J/KG OF
ML CAPE CAN DEVELOP ACCORDING TO PROGGED SOUNDINGS. WITH DEEP
MIXING AND 0-6KM BULK SHEAR AROUND 30KTS...THINK SEVERE WEATHER IS
POSSIBLE TOMORROW AFTERNOON. DAMAGING WIND GUSTS AND LARGE HAIL
WILL BE THE MAIN THREATS. SHOULD FEEL LESS HUMID OUT THERE THAN
TODAY...BUT HIGHS SHOULD STILL REACH INTO THE LOW TO MID 80S.
.LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY
ISSUED AT 225 PM CDT WED JUN 26 2013
IN GENERAL...MAINLY DIURNAL CONVECTION ANTICIPATED
WITH AS A SHORT WAVE CARVES OUT A DEEP UPPER TROUGH OVER THE
GREAT LAKES THROUGH EARLY SATURDAY FOLLOWED WITH A TREND FOR DRIER
AND COOLER AIR IN THE NORTH FLOW FOR THE REST OF THE WEEKEND INTO
THE FIRST HALF OF NEXT WEEK.
DIURNAL CONVECTION TO BE ON THE DECREASE THURSDAY NIGHT IN THE
WEAK CYCLONIC FLOW. WILL CONTINUE THE TREND OF MAINLY EVENING
SHOWERS CHANCES FOR MOST LOCATIONS. OTHERWISE SHOWERS WITH
ISOLATED STORMS TO BE ON THE INCREASE AGAIN FRIDAY AS THE COOLER
UPPER TROUGH SLOWLY DRIFTS SOUTHWARD OVER THE GREAT LAKES REGION.
AGAIN A DIURNAL DECREASE MAY OCCUR LATER FRIDAY EVENING...BUT
SHOWER ACTIVITY NOT LIKELY TO END UNTIL THE TROUGH AXIS SHIFTS FAR
ENOUGH SOUTH. THE ECMWF AND GFS WERE THE MOST PROGRESSIVE WITH THE
TROUGH AND PCPN SOUTH OF THE AREA SATURDAY MORNING. THE NAM IS
MUCH SLOWER WITH THE TROUGH PASSAGE AND HANGS ONTO PCPN THROUGH
SATURDAY AFTERNOON.
EVENTUALLY COOLER DRIER ON NORTHERLY WINDS WILL SWEEP SOUTH OVER
THE WESTERN GREAT LAKES LATER SATURDAY THROUGH THE FIRST FEW DAYS
OF THE NEXT WEEK AS THE CANADIAN SURFACE HIGH PRESSURE SETTLES IN.
PCPN CHANCES BEGIN TO RETURN AFTER TUESDAY AS THE GFS PROG THIS
DEEP TROUGH TO CUT OFF INTO AN UPPER LOW AND RETROGRADE BACK INTO
WESTERN GREAT LAKES REGION. THE ECMWF HAS A SIMILAR SOLUTION BUT
DROPS ANOTHER PIECE OF ENERGY INTO THE NORTHERN PLAINS IN THE
NORTHWEST FLOW. RETURN FLOW TUESDAY INTO WEDNESDAY CONFINED TO
THE ROCKIES AND NORTHERN PLAINS SO WILL KEEP POPS ON THE LOW SIDE.
IN ADDITION...ANY CONVECTION WHICH CAN DEVELOP WILL LIKELY BE
DIURNAL.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1238 PM CDT WED JUN 26 2013
SHOWERS AND THUNDERSTORMS OVER THE WI/MN BORDER WILL TRACK EAST
TODAY AND INTO NORTH-CENTRAL WISCONSIN LATER THIS AFTERNOON. OTHER
POP UP STORMS ARE POSSIBLE OVER CENTRAL WISCONSIN TOO...BUT WILL
PROBABLY HAVE TO WAIT UNTIL THIS EVENING FOR STORMS TO REACH EASTERN
WISCONSIN. POTENTIAL IS THERE FOR STRONG GUSTY WINDS AND HEAVY
DOWNPOURS WITHIN ANY THUNDERSTORMS. STORMS WILL EXIT LATE
TONIGHT...BUT THE MOIST AIRMASS WILL LINGER. WITH LIGHT
WINDS...PATCHY DENSE FOG IS POSSIBLE LATE TONIGHT...ESPECIALLY WHERE
IT RAINS. ONCE ANY FOG BURNS OFF BY MID-MORNING...MORE STORMS WILL
BE POSSIBLE TOMORROW AFTERNOON.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......TDH
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS TAUNTON MA
446 AM EDT FRI JUN 28 2013
.SYNOPSIS...
WARM AND MUGGY CONDITIONS WILL CONTINUE WITH HIT AND MISS SHOWERS
AND THUNDERSTORMS INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
400 AM UPDATE...OVERALL FORECAST TREND REMAINS ON TRACK. HAVE
UPDATED TO ACCOUNT FOR CURRENT SITUATION. APPEARS WARM FRONT IS
DRAPED FROM PROVINCETOWN THOUGH HARTFORD CT. EXPECT THIS FRONT TO
CONTINUE NORTHWARD AS LOW PRESSURE STRENGTHENS. WINDS GUSTS MAY
INCREASE ACROSS THE WEST AS PRESSURE GRADIENT TIGHTENS...UP TO
25KTS. PER VWP...LLJ IS STILL PUSHING THROUGH AS 925 VWP SHOW
AROUND 35-40 KTS. THE AXIS OF THE LLJ WILL TRANSITION MORE OVER
THE CAPE AND ISLANDS OVER THE NEXT FEW HOURS. ISOLATED TO
SCATTERED SHOWERS WILL STILL MOVE ACROSS THE REGION OVER THE NEXT
SEVERAL HOURS. BEST REGION IS OVER THE NW PORTION OF THE REGION.
TODAY...
*** FLASH FLOOD WATCH IS IN EFFECT THROUGH THIS AFTERNOON. ***
LOW PRESSURE SYSTEM WILL SLIDE NORTHWARD BY FRIDAY. THIS WILL
PUSH THE WARM FRONT/BOUNDARY NORTHWARD INTO NH ALLOWING FOR GOOD
SOUTHERLY FLOW ACROSS THE REGION. SCATTERED SHOWERS WILL CONTINUE
ESP ACROSS THE NORTHWEST PORTION OF THE REGION THIS MORNING. A FEW
EMBEDDED THUNDERSTORMS MAY OCCUR AS WELL. OTHERWISE BELIEVE
OVERALL AREAL COVERAGE WILL BE DISSIPATING. LOW LEVEL JET WILL
STILL BE ANCHORED ACROSS THE CAPE/EASTERN WATERS THROUGH THE DAY
WHICH COULD MAKE THINGS A TAD BREEZY ACROSS THE CAPE AND ISLANDS.
MODELS ARE SHOWING SOME DRYING IN THE MID-LEVELS BY LATE THIS
MORNING INTO THE EARLY AFTERNOON HOURS. MAIN QUESTION IS THE
POTENTIAL FOR STRONG THUNDERSTORMS LATER TODAY. MODELS ARE
INDICATING THAT CLOUD COVER WILL BREAK LATER ALLOWING FOR SOME
DIURNAL HEATING AND EVENTUALLY SOME THUNDERSTORMS. THE HI-RES WRF
AS WELL AS THE HRRR AND OTHER MESOSCALE MODELS ARE ALSO INDICATING
THIS FEATURE. IF THIS DOES PLAY OUT BELIEVE THE REGION THAT HAS
THE BEST POTENTIAL WILL BE ACROSS THE WORCESTER HILLS AND WEST.
THIS REGION SHOWS THE BETTER INSTABILITY...UP TO 2000 J/KG
COMBINED WITH BULK SHEAR VALUES AROUND 30KTS AND LAPSE RATES OF 6
C/KM. ALSO HAVE UPPER LEVEL SUPPORT AS THE EXIT REGION OF THE JET
MOVES OVER SOUTHERN NEW ENGLAND. IF THUNDERSTORMS DO DEVELOP
BELIEVE THAT GUSTY WINDS...HAIL AND HEAVY DOWNPOURS WILL BE THE
MAIN THREATS. SPC HAS OUTLOOKED MOST OF THE REGION WITHIN THEIR
DAY 1 OUTLOOK. WE HAVE ALSO BEEN PLACED IN A 2 PERCENT TORNADO
PROBABILITY. BELIEVE THE POTENTIAL IS LOW ESP SINCE SURFACE WINDS
WILL BE MORE OUT OF THE SOUTH RATHER THAN THE WSW ALTHOUGH IT IS
SOMETHING FOR THE DAY SHIFT TO EVALUATE.
TEMPERATURES WILL BE TRICKY AGAIN TODAY. WARM FRONT WILL LIFT
NORTHWARD ALLOWING FOR WARM AND MOIST AIR INTO THE REGION. HOWEVER
FOG AND CLOUDS WILL LIMIT TRUE DIABATIC HEATING. RIGHT NOW EXPECT
TEMPS TO BE IN THE MID TO UPPER 70S. IF THE SUN DOES PEAK OUT THEN
TEMPS MAY WARM INTO THE LOW 80S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
ANY ONGOING CONVECTION SHOULD DWINDLE DOWN DURING THE EVENING
HOURS AS DIURNAL HEATING IS LOST. STILL LEFT SCATTERED SHOWERS
IN THE FORECAST. OTHERWISE MAIN CONCERN WILL BE FOG FOR THE
OVERNIGHT HOURS AS VERY HUMID AIRMASS IS STILL IN PLACE. MODELS
ARE INDICATING ANOTHER SURGE OF PRECIP TO PUSH ACROSS THE CAPE AND
ISLANDS AFTER MIDNIGHT FROM THE LLJ.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
OVERVIEW...NOT MUCH CHANGE IN THE OVERALL SYNOPTIC PATTERN WITH
THE 28/00Z GUIDANCE. STILL DO NOT HAVE MUCH CONFIDENCE IN THE
MESOSCALE DETAILS EVIDENT IN ANY PARTICULAR MODEL. WITH ABOVE
AVERAGE AGREEMENT WITH RESPECT TO THE OVERALL SYNOPTIC
EVOLUTION...DECIDED TO USE A CONSENSUS BLEND TO TREND THE EXISTING
FORECAST.
THIS SOLUTION WILL FEATURE STRONG RIDGES DEVELOPING OVER THE
WESTERN USA AS WELL AS THE WESTERN ATLANTIC. A SHORTWAVE MOVING
OVER THE GREAT LAKES INTO THE MISSISSIPPI VALLEY AND FORMS AN
ANOMALOUSLY STRONG CUTOFF LOW OVER THAT AREA. THIS UPPER LOW
EVENTUALLY EJECTS INTO THE /CANADIAN/ WESTERLIES DURING THE MIDDLE
OF NEXT WEEK.
THE DAILIES...
SATURDAY... ANOTHER SHORTWAVE ROTATES AROUND A GREAT LAKES UPPER
LOW AND CROSSES EASTERN NY/NEW ENGLAND. A SUPPORTING UPPER JET HAS
ITS RIGHT ENTRANCE REGION OVER NEW ENGLAND. A COLD FRONT STALLS
OVER OR NEAR THE REGION AND PROVIDES A FOCUS FOR LOW LEVEL
CONVERGENCE. PLENTY OF MOISTURE AVAILABLE WITH PRECIPITABLE WATER
VALUES BETWEEN 1.5 AND 2.0 INCHES...HIGHEST SOUTHEAST. WE WILL
FEATURE HIGHER POPS. WE WILL ALSO MENTION LOCALLY HEAVY DOWNPOURS
DUE TO THE HIGH MOISTURE CONTENT.
SUNDAY THROUGH THURSDAY...NOT MUCH CHANGE IN THE UPPER PATTERN
WITH CLOSED LOW TO THE WEST AND UPPER RIDGE TO THE EAST...AND A
MOIST SOUTH FLOW CONTINUING TO SUPPLY HIGH MOISTURE CONTENT AIR.
WE WILL CONTINUE TO FEATURE AT LEAST A CHANCE OF SHOWERS AND
THUNDERSTORMS IN THE FORECAST.
&&
.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
BEFORE 12Z...HIGH CONFIDENCE ON TRENDS...MODERATE CONFIDENCE ON
TIMING. SCATTERED SHOWERS AND ISOLATED THUNDER WILL CONTINUE TO
MOVE ACROSS SNE. A MIXTURE OF IFR/LIFR IS EXPECTED THROUGH THE
MORNING HOURS FROM LOW CLOUDS AND FOG.
AFTER 12Z...MODERATE CONFIDENCE. IFR/LIFR CONDITIONS
EARLY...IMPROVING TO MVFR/IFR EAST AND MVFR/PATCHY VFR WEST. OVERALL
IMPROVEMENTS BY LATE MORNING WEST TO EAST. HOWEVER SHOWERS AND
THUNDERSTORMS WILL DEVELOP DURING THE LATE MORNING AND AFTERNOON
HOURS. THEREFORE MVFR OUT WEST IN ANY HEAVY THUNDERSTORM.
TONIGHT...VFR/MVFR WILL SLOWLY DROP TO MVFR/IFR ACROSS THE REGION IS
LOW CLOUDS AND FOG. BEST REGION FOR LOWEST CONDITIONS WILL BE ALONG
THE SOUTH COAST.
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. CONFIDENT IN OVERALL
TRENDS HOWEVER LOW CONFIDENCE IN TIMING.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF. CONFIDENT IN OVERALL
TRENDS HOWEVER LOW CONFIDENCE IN TIMING.
OUTLOOK...SATURDAY THROUGH TUESDAY...
MODERATE CONFIDENCE.
PLENTY OF SHOWERS/TSTMS THIS WEEKEND WITH PERIODS OF MVFR
CIGS/VSBYS IN SHOWERS...SOME OF THEM QUITE HEAVY. THE VERY HUMID
AIRMASS WILL ALSO PRODUCE AREAS OF FOG AT NIGHT AND EARLY MORNING
WITH IFR CIGS/VSBYS IN ANY SUCH FOG. POTENTIAL FOR VSBYS NEAR 1/4
MILE AT TIMES.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT-TERM THROUGH FRIDAY...HIGH CONFIDENCE.
SHORT-TERM THROUGH FRIDAY NIGHT...HIGH CONFIDENCE.
SCA STILL CONTINUES ACROSS THE WATERS. CONTINUED TO UNDERCUT WNA
WAVE GUIDANCE BY ABOUT 10 PERCENT TO ACCOUNT FOR ITS SOUTHERLY
BIAS. OTHERWISE SHOWERS AND THUNDERSTORMS WILL CONTINUE TO
IMPACT THE WATERS TODAY AND INTO TONIGHT. MAIN THREATS WILL BE
LIGHTNING AND HEAVY DOWNPOURS IMPACTING VISIBILITIES.
OUTLOOK...SATURDAY THROUGH TUESDAY...
PERIODS OF SHOWERS/TSTMS/FOG EXPECTED WITH VERY HUMID AIR
CONTINUING. THERE WILL BE POOR VSBYS AT TIMES...AND 1/4 MILE
VSBYS IN FOG POSSIBLE EARLY EACH MORNING. SOUTH TO SOUTHWEST WINDS
THROUGH THE PERIOD. WIND GUSTS MAY APPROACH 25 KNOTS AT TIMES
SATURDAY...BUT BE PRIMARILY 20 KNOTS OR LESS. THE STEADY WIND
DIRECTION WILL HELP BUILD SEAS WITH WAVE HEIGHTS OF 5 TO 10 FEET
EXPECTED ACROSS THE OUTER COASTAL WATERS AND EXPOSED PORTIONS OF
THE SOUTHERN SOUNDS SUCH AS RI SOUND AND POSSIBLY BLOCK ISLAND
SOUND. A SMALL CRAFT ADVISORY WILL BE NEEDED FOR THESE ROUGH SEAS
THROUGH MIDWEEK...ESPECIALLY ACROSS THE OUTER COASTAL WATERS.
&&
.HYDROLOGY...
FLASH FLOOD WATCH CONTINUES THROUGH TODAY. RADAR ESTIMATED
RAINFALL RATES UP TO 6 IN PER HOUR WITHIN SOME OF THE STRONGER
THUNDERSTORMS LAST NIGHT. FORTUNATELY THESE THUNDERSTORMS REMAINED
PROGRESSIVE AND DID NOT LINGER OVER ANY ONE LOCATION FOR VERY
LONG. THESE RAINFALL RATES DO INDICATE THE POTENTIAL FOR HEAVY
RAINFALL WITHIN THIS SOUPY AIRMASS.
WILL NEED TO ESPECIALLY WATCH REGIONS OF HIGHER TERRAIN WHERE
UPSLOPE COULD ENHANCE THE RAINFALL AS WELL AS URBANIZED AREAS...
WHERE CONVECTIVE HEAVY RAIN MAY LEAD TO URBAN FLASH FLOODING.
&&
.CLIMATE...
WITH THE POTENTIAL FOR HEAVY RAIN TONIGHT INTO FRIDAY WE WILL BE
ADDING TO THE ALREADY HIGH MONTHLY TOTALS FOR RAIN. BELOW PLEASE
FIND THE TOP 10 WETTEST JUNE RAINFALL TOTALS FOR EACH OF OUR FOUR
CLIMATE SITES...THESE INCLUDE RAINFALL TOTALS FOR JUNE 2013 ENDING
AT MIDNIGHT THE MORNING OF JUNE 27.
BOSTON...
1. 13.20 INCHES IN 1982
2. 11.58 INCHES IN 1998
3. 10.09 INCHES IN 2006
4. 9.87 INCHES IN 2013
5. 9.13 INCHES IN 1931
6. 8.63 INCHES IN 1959
7. 8.05 INCHES IN 1922
8. 7.79 INCHES IN 1881
9. 7.74 INCHES IN 1986
10. 7.25 INCHES IN 1875
HARTFORD...
1. 13.60 INCHES IN 1982
2. 10.62 INCHES IN 2013
3. 9.66 INCHES IN 1972
4. 9.16 INCHES IN 2006
5. 8.08 INCHES IN 1937
6. 8.00 INCHES IN 1920
7. 7.79 INCHES IN 1948
8. 7.18 INCHES IN 1998
9. 6.92 INCHES IN 1922
10. 6.79 INCHES IN 1986
PROVIDENCE...
1. 11.08 INCHES IN 1982
2. 9.61 INCHES IN 1998
3. 9.39 INCHES IN 2013
4. 9.24 INCHES IN 2006
5. 7.21 INCHES IN 1938
6. 6.83 INCHES IN 1978
7. 6.80 INCHES IN 1920
8. 6.72 INCHES IN 2001
9. 6.58 INCHES IN 1922
10. 5.84 INCHES IN 1989
WORCESTER...
1. 12.17 INCHES IN 1982
2. 9.68 INCHES IN 1998
3. 9.55 INCHES IN 2013
4. 9.25 INCHES IN 1972
5. 8.31 INCHES IN 1922
6. 7.78 INCHES IN 1968
7. 7.44 INCHES IN 1903
8. 7.39 INCHES IN 1938
9. 7.21 INCHES IN 1986
10. 6.98 INCHES IN 1973 & 1935
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR CTZ002>004.
MA...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR MAZ002>021-026.
NH...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR NHZ011-012-015.
RI...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR RIZ001>007.
MARINE...SMALL CRAFT ADVISORY FROM 8 AM THIS MORNING TO 8 PM EDT THIS
EVENING FOR ANZ231>234.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR ANZ235-237-
254>256.
SMALL CRAFT ADVISORY FROM 8 AM THIS MORNING TO 6 PM EDT
SATURDAY FOR ANZ250.
&&
$$
SYNOPSIS...DUNTEN/BELK
NEAR TERM...DUNTEN
SHORT TERM...DUNTEN
LONG TERM...BELK
AVIATION...DUNTEN/BELK
MARINE...DUNTEN/BELK
HYDROLOGY...BELK
CLIMATE...STAFF
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
303 AM CDT FRI JUN 28 2013
.SYNOPSIS...
ISSUED AT 300 AM CDT FRI JUN 28 2013
WATER VAPOR LOOPS SHOWED A BROAD UPPER TROUGH ACROSS THE GREAT
LAKES WITH A CLOSED LOW ON THE NORTHERN TIP OF LAKE SUPERIOR. A
STRONG SHORT WAVE/VORT MAX WAS LOCATED IN NORTHEAST MN. A FEW
SHOWERS WERE NOTED IN CENTRAL WI. OTHERWISE CLEAR SKIES WERE
ACROSS THE DVN CWA WHILE A LARGE MCS WAS COVERING SOUTHERN MO
AHEAD OF A COLD FRONT. CURRENT TEMPERATURES IN THE DVN CWA RANGED
FROM THE MID 60S TO LOWER 70S WITH DEWPOINTS IN THE UPPER 50S NW
TO UPPER 60S SE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 300 AM CDT FRI JUN 28 2013
FORECAST FOCUS ON SHOWER CHANCES...CLOUD TRENDS AND TEMPERATURES.
TODAY...OPERATIONAL MODELS SLIDE THE GREAT LAKES TROUGH SOUTHWARD
INTO OUR REGION WITH THE RAP DEPICTING A STRONG VORT MAX MOVING
FROM NORTHEAST MN INTO NORTHERN IL THIS AFTERNOON. WITH COOLING
TEMPERATURES ALOFT COMBINED WITH DAYTIME HEATING INSTABILITY WILL
INCREASE. HAVE CONFINED POPS TO THIS AFTERNOON AND ALSO ACROSS OUR
NORTHEAST HALF CWA CLOSER TO THE TRACK OF THE VORT MAX. THE HRRR
MESO MODEL DEPICTS THE POPCORN DESCRIPTION OF THE SCATTERED INSTABILITY
SHOWERS (AND A FEW THUNDERSTORMS) QUITE WELL. THERE WILL BE PLENTY OF
SUNSHINE FOR MOST OF THIS MORNING BUT CLOUDS WILL DEVELOP/FILL AS
THE CONVECTIVE TEMPERATURE IS REACHED. MAXIMUM TEMPERATURES WILL
RANGE FROM THE UPPER 70S NORTH TO THE MID 80S SOUTH BUT HUMIDITY
LEVELS WILL BE THANKFULLY LOWER COMPARED TO THE LAST FEW DAYS.
TONIGHT...WITH THE UPPER TROUGH OVER THE AREA WILL CONTINUE WITH
CHANCE POPS AS SKIES WILL BE MOSTLY CLOUDY OR BECOME MOSTLY CLOUDY.
HOWEVER...WITH THE LOSS OF HEATING/BETTER INSTABILITY THE COVERAGE OF
SHOWERS WILL DECREASE OVERNIGHT. MINIMUM TEMPERATURES SHOULD BE IN
THE LOWER 60S AT MOST LOCATIONS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 300 AM CDT FRI JUN 28 2013
A DIGGING UPPER TROF OVER THE EASTERN U.S IS FORECAST TO CLOSE OFF
OVER THE OHIO VALLEY BY LATE IN THE WEEKEND. THEN...MODELS ARE IN
AGREEMENT THAT THE CLOSED LOW WILL RETROGRADE INTO THE MID
MISSISSIPPI VALLEY EARLY IN THE WEEK AND REMAIN THERE...THEN
GRADUALLY FILLING DURING THE LATTER HALF OF THE WEEK.
THIS PATTERN WILL SUPPORT BELOW NORMAL TEMPERATURES THROUGH THE
FORECAST PERIOD WITH HIGHS GENERALLY IN THE 70S TO AROUND 80 AND
LOWS...ESPECIALLY EARLY IN THE WEEK...IN THE 50S.
MOST DAYS WILL HAVE AT LEAST A LOW THREAT OF RAIN.
HOWEVER...AS STATED IN THE PREVIOUS DISCUSSION...THE RAIN THREAT
WILL BE LIMITED TO JUST A FEW HOURS EACH DAY.
THE BETTER CHANCE OF RAIN DURING THE PERIOD WILL BE SATURDAY AS A
SERIES OF S/WS DROP INTO THE DEVELOPING TROF TO OUR EAST. THE
BETTER UPPER FORCING APPEARS TO BE JUST EAST OF THE
FORECAST AREA...SO KEPT THE HIGHER CHANCE AND LIKELY POPS NEAR AND
EAST OF THE MISSISSIPPI RIVER. THE RAIN THREAT WILL DIMINISH
SATURDAY NIGHT AND SUNDAY AS DRIER LOW LEVEL AIR FILTERS IN FROM THE
NORTH. THE DRY WEATHER SHOULD LAST THROUGH MONDAY THEN A LOW RAIN
THREAT RETURNS MONDAY NIGHT THROUGH THE END OF THE WEEK AS THE UPPER
LOW BACKS INTO THE REGION FROM THE EAST. THIS WILL SUPPORT MAINLY
AFTERNOON ISOLATED TO SCATTERED SHOWERS OR THUNDERSTORMS. SINCE ANY
SHRA/TSRA ACTIVITY WILL PROBABLY BE TIED TO AFTERNOON HEATING...HAVE
LIMITED THE POPS TO THE DAYTIME HOURS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 300 AM CDT FRI JUN 28 2013
CLEAR SKIES AND LIGHT WINDS WILL REMAIN OVER THE AREA INTO THIS MORNING.
AN UPPER LEVEL DISTURBANCE PASSING THROUGH THE REGION WILL PRODUCE
SCATTERED SHOWERS AND THUNDERSTORMS...MAINLY THIS AFTERNOON. THIS IS
MOST LIKELY TO IMPACT THE DBQ SITE AND A TEMPO GROUP HAS BEEN
ADDED. CID AND MLI MAY ALSO SEE AFTERNOON THUNDERSTORMS...BUT
CONFIDENCE THAT THESE SITES WILL BE DIRECTLY IMPACTED IS NOT HIGH
ENOUGH TO GO BEYOND PROB30 WORDING. OTHERWISE...CONDITIONS WILL
REMAIN VFR WITH WEST TO NORTHWEST WINDS INCREASING AND BECOMING
GUSTY FROM 15 TO 25 KTS FROM LATE MORNING THROUGH THIS AFTERNOON.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...DLF
AVIATION...HAASE
AREA FORECAST DISCUSSION
NWS TOPEKA KS
305 AM CDT FRI JUN 28 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 305 AM CDT FRI JUN 28 2013
THUNDERSTORMS CONTINUE TO MOVE SOUTHEAST ACROSS MISSOURI AND FAR
SOUTHEAST KANSAS AT 07Z. A SURFACE HIGH WAS BUILDING INTO THE PLAINS
FROM MONTANA. SURFACE DEW POINTS CONTINUED IN THE MID TO UPPER 60S
ACROSS THE CWA THIS MORNING. LATEST SATELLITE WATER VAPOR LOOP HAD A
MID LEVEL HIGH OVER THE WESTERN STATES AND ROCKIES WHILE A TROUGH
WAS OVER THE GREAT LAKES.
TODAY AND TONIGHT THE MID LEVEL HIGH WILL BUILD SLOWLY EASTWARD
WHILE THE MID LEVEL TROUGH DEEPENS ACROSS THE EASTERN U.S.. THIS
WILL KEEP THE CENTRAL PLAINS IN A NORTHWEST FLOW PATTERN ALOFT. THE
WAVES MOVING THROUGH THE TROUGH WILL REMAIN WELL TO THE EAST. THE
SURFACE HIGH PRESSURE WILL CONTINUE TO BUILD INTO KANSAS TODAY AND
TONIGHT. THIS WILL BRING LOWER HUMIDITY AS DRIER AIR FILTERS INTO
NORTH CENTRAL AND NORTHEAST KANSAS. FORECAST SOUNDINGS SHOW THE WE
SHOULD MIX DOWN FROM AROUND 800 MB THIS AFTERNOON. THIS WILL YIELD
HIGHS IN THE MID 80S TO LOWER 90S WITH THE COOLER TEMPERATURES IN
THE NORTHEAST CORNER. MOSTLY CLEAR SKIES EXPECTED TONIGHT AND WITH
THE SURFACE HIGH BUILDING IN WILL SEE TEMPS COOL INTO THE LOWER TO
MIDDLE 60S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 305 AM CDT FRI JUN 28 2013
UPPER JET CORE WILL BE OVERHEAD FOR MUCH OF THE WEEKEND ON THE
WESTERN QUADRANT OF THE OHIO VALLEY UPPER TROF. MODELS CONTINUE TO
SUGGEST SOME LIGHT PRECIP COULD DEVELOP THIS FAR WEST BUT SOUNDINGS
ARE NOT SUGGESTIVE OF MUCH IF ANY INSTABILITY AND MOISTURE IS RATHER
LIMITED. AM CONFIDENT ENOUGH TO REMOVE PRECIP MENTION HERE. WEAK
UPPER FORCING IS AGREED UPON FOR EASTERN AREAS LATE SUNDAY INTO
SUNDAY NIGHT BUT THIS COMES INTO AN EVEN DRYER AND MORE STABLE
ATMOSPHERE SO WILL KEEP THESE PERIODS DRY AS WELL. WINDS WILL BE ON
THE BREEZY SIDE DURING MUCH OF THE DAYTIME HOURS AS MIXING DEPTHS
REACH SEVERAL THOUSAND FEET WITH A DECENT HEIGHT GRADIENT IN PLACE.
LOW LEVEL TRAJECTORIES CONTINUE TO VEER TO A NORTH THEN NORTHEAST
FOR A STEADY COOL-DOWN...WITH HIGHS POSSIBLY NOT BREACHING 80 IN THE
EAST ON SUNDAY.
MID RANGE MODELS ARE VERY CONSISTENT WITH THE BLOCKING REGIME OVER
THE 30N-50N LATITUDES SLOWLY BREAKING DOWN THROUGH THE WORK WEEK WITH
BROAD UPPER TROFFING RETROGRADING INTO THE PLAINS BY WEDNESDAY. NEAR
MOIST ADIABATIC LAPSE RATES ABOVE THE BOUNDARY LAYER AND LITTLE IF
ANY FORCING SHOULD ANY PRECIP IN CHECK THROUGH AT LEAST TUESDAY
NIGHT. BY THURSDAY LEE TROFFING DEVELOPS ENOUGH FOR RISING LOW LEVEL
THETA VALUES AND A MORE FAVORABLE KINEMATIC SETUP FOR HIGH PLAINS
CONVECTION TO PUSH INTO EASTERN KANSAS BUT PRECIP CHANCES STILL LOOK
LOW AT THIS POINT. TEMPERATURES WILL SLOWLY MODIFY TO NEAR EARLY
JULY NORMALS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1149 PM CDT THU JUN 27 2013
WITH CONVECTION MOVING TO THE SOUTHEAST OF THE TERMINALS AND WEAK
SURFACE RIDGING EXPECTED TO BUILD INTO THE AREA...ANTICIPATE VFR
CONDITIONS TO PREVAIL THROUGH FRIDAY WITH A NORTH AND NORTHWEST
WIND. THE RAP AND NAM ARE HINTING AT SOME WEAK INSTABILITY
DEVELOPING WITH NO CIN ACROSS EAST CENTRAL KS. IF THERE WERE
ENOUGH LOW LEVEL CONVERGENCE...AND ISOLATED STORM MAY BE POSSIBLE.
HOWEVER PREDICTABILITY IS TO LOW TO MENTION IN THE TAFS AT THIS
TIME.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...53
LONG TERM...65
AVIATION...WOLTERS
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1149 PM CDT THU JUN 27 2013
.SHORT TERM...(THIS EVENING) ISSUED AT 1232 PM CDT THU JUN 27
2013
AT 18Z...AN OUTFLOW BOUNDARY EXTENDED FROM NEAR OTTAWA TO JUNCTION
CITY TO WASHINGTON...AND HAD ALREADY MIXED OUT A BIT NEAR THE
NEBRASKA BORDER AS EVIDENCED BY BEATRICE WINDS TURNING OUT OF THE
SSE. THE COLD SIDE OF THE OUTFLOW HAD STABILIZED A BIT AT THE
SURFACE BUT ELEVATED PARCELS REMAINED VERY UNSTABLE. MEANWHILE...
THE WARM SIDE OF THE OUTFLOW WAS EXTREMELY UNSTABLE WITH DEWPOINTS
IN THE MID 70S AND TEMPERATURES CLIMBING WELL INTO THE 90S. DEEP
LAYER SHEAR IS SUFFICIENT FOR SUPERCELL STRUCTURES PARTICULARLY
WHEN COMBINED WITH THE EXTREME INSTABILITY IN PLACE. A SOMEWHAT
ORGANIZED AREA OF CONVECTION HAS BEEN STEADILY MOVING SSE ACROSS
SOUTHEAST NEBRASKA AND HAS SHOWN SIGNS OF INCREASING ORGANIZATION
AND DEVELOPMENT ON THE WESTERN FLANK WHERE THE INSTABILITY FEED IS
MORE SUBSTANTIAL.
FEEL THAT THE MOST LIKELY SCENARIO FOR THIS AFTERNOON AND EVENING
IS FOR THE ACTIVITY IN SOUTHERN NEBRASKA TO FURTHER ORGANIZE...
LIKELY DEVELOPING A FORWARD PROPAGATING COLD POOL WHILE ALSO
MAINTAINING EMBEDDED SUPERCELL STRUCTURES. THIS SEEMS TO BE A
RATHER FAVORABLE SETUP FOR A DAMAGING WIND EVENT...ESPECIALLY
ANYWHERE ON THE WARM SIDE OF THE OUTFLOW BOUNDARY BUT PERHAPS
EXTENDING INTO THE COOL SIDE OF THE OUTFLOW BY 100 MILES OR SO AS
WELL. THE MAGNITUDE OF INSTABILITY ALONG WITH THE SHEAR PROFILE
SUGGEST THE POTENTIAL FOR VERY LARGE HAIL...PERHAPS ACCOMPANIED BY
VERY STRONG WINDS AT TIMES. TORNADO POTENTIAL IS NON-ZERO...BUT
WOULD SEEM TO BE LIMITED TO AREAS WHERE THE STORMS INTERSECT THE
REMNANT OUTFLOW BOUNDARY AND TO ANY ORGANIZED CELLS ON THE WEST
END OF ANY BOW ECHO. WOULD ALSO NEED TO KEEP AN EYE ON ANY BOOKEND
VORTEX THAT COULD DEVELOP IN A WELL ORGANIZED BOW ECHO. THE BOTTOM
LINE IS THAT AN ORGANIZED SEVERE WEATHER THREAT IS EXPECTED THIS
AFTERNOON WITH THE PRIMARY THREATS BEING A COMBINATION OF WINDS UP
TO 80 MPH AND HAIL UP TO TENNIS BALL SIZE. DO EXPECT STORMS TO
COME TO AN END BY LATE EVENING WITH MORE PLEASANT CONDITIONS
EVENTUALLY SETTLING INTO THE AREA BEHIND AN INCOMING COLD FRONT.
BARJENBRUCH
.LONG TERM...(FRIDAY THROUGH THURSDAY) ISSUED AT 246 PM CDT THU
JUN 27 2013
THE EXTENDED PERIOD OF THE FORECAST WILL BE MARKED BY A FAIRLY QUIET
WEATHER PATTERN AND COOLER THAN NORMAL TEMPERATURES. ONCE TODAY`S
STORM SYSTEM TRACKS SOUTHEAST OF THE AREA OVERNIGHT...THE MID LEVEL
RIDGE OVER THE WESTERN U.S. WILL CONTINUE TO AMPLIFY AS THE MID
LEVEL TROUGH OVER THE EASTERN U.S. DIGS FURTHER SOUTH ALONG THE
ATLANTIC COASTLINE. THIS PATTERN WILL REMAIN ANCHORED OVER THE CONUS
THROUGH THE WEEKEND INTO EARLY NEXT WEEK...KEEPING THE CENTRAL
PLAINS IN NORTHWESTERLY FLOW. THIS NORTHWESTERLY FLOW WILL RESULT IN
COOLER TEMPERATURES IN THE UPCOMING DAYS...WITH HIGHS IN THE UPPER
80S/LOWER 90S ON FRIDAY AND DROPPING SLIGHTLY BELOW THE SEASONAL
NORMALS THIS WEEKEND WITH HIGHS GENERALLY IN THE LOWER TO MIDDLE
80S. WITH SURFACE HIGH PRESSURE BUILDING IN BEHIND THE EXITING
SYSTEM...EXPECT DRY CONDITIONS FRIDAY...THROUGH THE WEEKEND AND INTO
EARLY NEXT WEEK. BY MID WEEK...THE MID LEVEL TROUGH LOOKS TO
RETROGRADE SOMEWHAT FURTHER WEST INTO THE NORTHERN AND CENTRAL
PLAINS AS A WAVE OVER CANADA MERGES INTO THE TROUGH. THE UPPER LEVEL
FLOW BECOMES A BIT MESSY BY MID TO LATE WEEK WITH THIS PATTERN
CHANGE. AN AREA OF LOW PRESSURE LOOKS TO MOVE INTO WESTERN KANSAS
WEDNESDAY INTO THURSDAY WITH AN ASSOCIATE BOUNDARY POTENTIALLY
EXTENDING EASTWARD TOWARD THE FORECAST AREA. BETTER CHANCES FOR
PRECIPITATION ENTER BACK INTO THE FORECAST TUESDAY NIGHT THROUGH
THURSDAY WITH THIS APPROACHING SYSTEM. HOWEVER...DUE TO THE
UNCERTAINTY IN THE EXACT TRACKING OF THIS SYSTEM...HAVE ONLY
INCLUDED SLIGHT CHANCE POPS AT THIS TIME. AS WINDS SHIFT MORE TO THE
SOUTH FROM THIS NEARBY SURFACE LOW...AFTERNOON HIGHS SHOULD START
WARMING A BIT CLOSER TO THE SEASONAL NORMALS BY THURSDAY WITH HIGHS
IN THE MIDDLE 80S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1149 PM CDT THU JUN 27 2013
WITH CONVECTION MOVING TO THE SOUTHEAST OF THE TERMINALS AND WEAK
SURFACE RIDGING EXPECTED TO BUILD INTO THE AREA...ANTICIPATE VFR
CONDITIONS TO PREVAIL THROUGH FRIDAY WITH A NORTH AND NORTHWEST
WIND. THE RAP AND NAM ARE HINTING AT SOME WEAK INSTABILITY
DEVELOPING WITH NO CIN ACROSS EAST CENTRAL KS. IF THERE WERE
ENOUGH LOW LEVEL CONVERGENCE...AND ISOLATED STORM MAY BE POSSIBLE.
HOWEVER PREDICTABILITY IS TO LOW TO MENTION IN THE TAFS AT THIS
TIME.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...BARJENBRUCH
LONG TERM...HENNECKE
AVIATION...WOLTERS
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
1107 PM CDT THU JUN 27 2013
...MESOSCALE UPDATE...
.MESOSCALE DISCUSSION...
ISSUED AT 1107 PM CDT THU JUN 27 2013
AFTER PERCOLATING ACROSS THE GREATER TOPEKA AREA FOR THE BETTER
PART OF 4 HOURS...SOMEWHAT DISORGANIZED CLUSTER OF CONVECTION IS
FINALLY STARTING TO MAKE ITS WAY SOUTHEAST INTO THE SGF CWA. MUCH
OF THIS CONVECTION HAS SEEMINGLY BEEN ROOTED JUST ABOVE THE
BOUNDARY LAYER...ON TOP OF A REMNANT COLD POOL FROM THE EARLY
EVENING MCS THAT AFFECTED MUCH OF KANSAS. THIS HAS LIKELY
PREVENTED THE CONVECTION FROM BECOMING BETTER ORGANIZED INTO A
FORWARD PROPAGATING MCS.
AS WE HEAD INTO THE OVERNIGHT HOURS...ANY CONVECTION THAT CAN MOVE
SOUTH INTO THE SGF CWA SHOULD HAVE AN OPPORTUNITY TO PRODUCE AT
LEAST SCATTERED SEVERE WEATHER...AS THE AIRMASS FURTHER SOUTH IS
FAR MORE FAVORABLE FOR SEVERE WEATHER (ESPECIALLY DAMAGING WIND
GUSTS) THAN ACROSS NORTHERN MISSOURI/NORTHEASTERN KANSAS. PRIMARY
THREAT REMAINS STRAIGHT LINE WIND GUSTS...WITH A SECONDARY THREAT
OF A FEW SEVERE HAIL STONES. THE TORNADO THREAT REMAINS NEARLY
ZERO.
STORMS MAY CONTINUE TO PERCOLATE FOR A WHILE ONCE THEY MOVE INTO
THE SGF CWA...THOUGH THE SEVERE THREAT SHOULD SLOWLY WANE WITH
TIME...GIVEN A SLOWLY COOLING BOUNDARY LAYER.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 330 PM CDT THU JUN 27 2013
WARM AND HUMID CONDITIONS ARE OCCURRING ACROSS THE REGION THIS
AFTERNOON. TEMPERATURES ARE GENERALLY IN THE LOWER TO MIDDLE 90S
WITH HEAT INDEX VALUES IN THE 100 TO 109 RANGE...WITH THE HIGHEST
READINGS OCCURRING ALONG AND SOUTHWEST OF AN OSCEOLA TO
SPRINGFIELD TO ALTON MISSOURI LINE. THESE CONDITIONS WILL PERSIST
THROUGH THE REMINDER OF THE AFTERNOON HOURS INTO EARLY THIS
EVENING. WILL KEEP THE HEAT ADVISORY GOING AS IS UNTIL 8 PM FOR
THESE LOCATIONS.
AN OUTFLOW BOUNDARY THAT DEVELOPED WITH CONVECTION ACROSS NORTHERN
MISSOURI THIS MORNING IS CURRENTLY PUSHING SOUTH ACROSS THE AREA
THIS AFTERNOON. THE AREA REMAINS FAIRLY CAPPED DUE TO A WARM
AIRMASS...AND VERY LITTLE DEVELOPMENT HAS OCCURRED ON THIS
BOUNDARY. A FEW ISOLATED STORMS HAVE BEEN ABLE TO DEVELOP ACROSS
CENTRAL MISSOURI AND MAY REMAIN POSSIBLE ACROSS THE EASTERN
OZARKS THIS AFTERNOON AS THE OUTFLOW PUSHES SOUTH...THOUGH MOST
LOCATIONS SHOULD REMAIN DRY.
A SURFACE FRONT IS CURRENTLY LOCATED ACROSS NORTHERN AND WESTERN
KANSAS THIS AFTERNOON AND STORMS ARE BEGINNING TO DEVELOP ON THIS
BOUNDARY. THIS TREND WILL CONTINUE THIS AFTERNOON AND THESE STORMS
WILL FORM INTO A LINE LATER THIS AFTERNOON AND WILL ACCELERATE TO
THE SOUTHEAST TOWARDS THE AREA THIS EVENING...EXITING THE AREA
OVERNIGHT. LOCATIONS WITH THE BETTER POTENTIAL TO BE AFFECTED BY
THIS ACTIVITY WILL BE FARTHER TO THE WEST...GENERALLY ALONG AND
WEST OF HIGHWAY 65. THERE ARE MORE QUESTIONS HOW FAR EAST OF
HIGHWAY 65 THIS ACTIVITY CAN MAKE IT....THOUGH THUNDERSTORMS ARE
STILL POSSIBLE EAST OF HIGHWAY 65 THIS EVENING INTO THE OVERNIGHT
HOURS. THE FORCING ALONG THE FRONT/COLD POOL THAT DEVELOPS FROM
THE STORMS ACROSS KANSAS SHOULD BE ENOUGH TO BREAK THE CAP ACROSS
THE AREA AND WITH STRONG THETA-E DIFFERENCE AND A VERY UNSTABLE
AIRMASS WILL RESULT IN A STRONG DAMAGING WIND RISK WITH WINDS IN
EXCESS OF 70 TO 80 MPH LIKELY ALONG THIS LINE WITH THE BEST
POTENTIAL FOR WINDS THAT STRONG BEING WEST OF INTERSTATE 49. THERE IS
A HAIL RISK...BUT WITH THESE STORMS EXPECTED TO BE LINEAR IN
NATURE THIS POTENTIAL IS MORE LIMITED WITH GENERALLY UP TO
QUARTERS POSSIBLE. TIMING OF THIS AREA WILL GENERALLY BE BETWEEN 7
AND 10 PM ALONG AND WEST OF THE INTERSTATE 49 CORRIDOR AND BETWEEN
8 AND MIDNIGHT WEST OF HIGHWAY 65. THERE ARE MORE QUESTIONS IF
THIS LINE OF STORMS CAN MAKE IT EAST OF HIGHWAY 65...AND WILL HAVE
TO SEE EXACTLY WHERE THIS LINE SETS UP ACROSS KANSAS.
FRIDAY SHOULD GENERALLY BE DRY...THOUGH AN ISOLATED AFTERNOON
THUNDERSTORM MAY BE POSSIBLE IF ENOUGH INSTABILITY CAN DEVELOP...
THOUGH THIS POTENTIAL LOOKS REALLY LIMITED. TEMPERATURES WILL BE COOLER
ON FRIDAY THAN TODAY...BUT HIGHS WILL STILL TOP OUT IN THE UPPER 80S
TO THE LOWER 90S.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 330 PM CDT THU JUN 27 2013
AN UPPER LEVEL LOW WILL BUILD SOUTHWEST OUT OF THE GREAT LAKES
REGION OVER THE CENTRAL U.S. THIS WEEKEND THROUGH MUCH OF NEXT
WEEK. THIS WILL PUSH THE UPPER LEVEL RIDGE AND HOT AND MUGGY
CONDITIONS BACK TO THE WEST AND ALLOW A COOLER AIRMASS TO SPREAD INTO
THE REGION. HIGHS THIS WEEKEND THROUGH NEXT WEEK WILL GENERALLY BE IN
THE UPPER 70S TO THE MIDDLE 80S EACH AFTERNOON AS LOWS DROP INTO
THE LOWER TO MIDDLE 60S EACH NIGHT. THERE COULD BE PERIODS OF
SHOWERS AND THUNDERSTORMS AT TIMES AS THE UPPER LEVEL LOW REMAINS
OVER THE REGION BUT NO SEVERE WEATHER OR WASH OUT IS EXPECTED.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 630 PM CDT THU JUN 27 2013
STRONG/SEVERE CONVECTION CONTINUES TO FIRE ALONG A COLD FRONT TO
THE WEST AND NORTHWEST OF THE CWA. IF THIS LINE CAN FILL IN
BETWEEN SALINA AND KANSAS CITY...IT WILL LIKELY AFFECT THE TAF
SITES THIS EVENING BETWEEN 02Z AND 04Z. IF IT DOESNT FILL IN...THE
CURRENT CONVECTION TO THE WEST WILL LIKELY MISS OUR SITES TO THE
WEST. HAVE CURRENTLY PUT IN A TEMPO GROUP...ROUGHLY USING THE
LATEST HRRR AS TIMING GUIDANCE AFFECTING THE TAF SITES THIS
EVENING. PRIOR TO AND AFTER THE CONVECTION...VFR CONDITIONS
EXPECTED. DURING CONVECTION...GENERALLY MVFR CONDITIONS EXPECTED.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
MESOSCALE...BOXELL
SHORT TERM...WISE
LONG TERM...WISE
AVIATION...LINDENBERG
AREA FORECAST DISCUSSION
NWS BUFFALO NY
501 AM EDT FRI JUN 28 2013
.SYNOPSIS...
LOW PRESSURE WILL SLOWLY LIFT ACROSS EASTERN NEW YORK TODAY...WITH
THIS LOW EXPECTED TO STALL NEAR THE REGION AS IT GRADUALLY
WEAKENS THROUGH THE WEEKEND. THIS WILL BRING PERIODS OF RAIN
TODAY...WITH EMBEDDED AREAS OF HEAVIER RAIN AND THUNDERSTORMS.
THE THREAT FOR SHOWERS AND PERHAPS A THUNDERSTORM WILL PERSIST
THROUGH THE WEEKEND...HOWEVER SHOWERS WILL BECOME INCREASINGLY
SCATTERED AS THE WEEKEND WEARS ON.
&&
.NEAR TERM /THROUGH TONIGHT/...
THERE CONTINUES TO BE A POTENTIAL FOR FLOODING ACROSS PORTIONS OF
WESTERN NEW YORK TODAY. THERE APPEARS TO BE TWO MAIN FEATURES TO
WATCH TODAY...WITH THE MOST OBVIOUS BEING THE LARGE AREA OF RAIN
ASSOCIATED WITH THE WEAK SURFACE LOW WHICH IS LIFTING ACROSS EASTERN
NEW YORK STATE. RADAR TRENDS SUPPORT THE HRRR HANDLING OF THIS
FEATURE...WHICH LARGELY KEEPS THE CORE OF IT TO THE SOUTH AND EAST
OF OUR CWA. THIS SAID...EXPECT A RATHER QUICK INCH OF RAIN ACROSS
LEWIS COUNTY THROUGH MID-MORNING...WITH LESSER AMOUNTS TO THE WEST
IN JEFFERSON/OSWEGO COUNTIES. IF THIS HOLDS...WE PROBABLY WILL NOT
SEE FLOODING...HOWEVER GIVEN THE CLOSE PROXIMITY OF HEAVIER RAINS WE
WILL KEEP UP THE FLOOD WATCH. UPSTREAM RAINS WILL LIKELY CAUSE
WITHIN BANK RISES ON THE BLACK RIVER AT BOONVILLE.
THE SECOND FEATURE WE WILL BE KEEPING A CLOSE EYE ON IS A MORE
SUBTLE UPPER LEVEL TROF AXIS WHICH EXTENDS FROM WESTERN NEW YORK
BACK INTO SOUTHERN ONTARIO TO GEORGIAN BAY. SCATTERED...BUT VERY
SLOW MOVING...SHOWERS ALONG THIS AXIS ARE FORECAST TO EXPAND BY THE
HRRR. SEVERAL RUNS OF THE NAM/RGEM SUPPORT THE HRRR FORECAST...AND GIVEN
A FAIRLY GOOD TRACK RECORD FOR THIS EVENT...HAVE MODERATE CONFIDENCE
IN ITS FORECAST. EXPECT SHOWERS TO DEVELOP ALONG A NW-SE AXIS ACROSS
WESTERN PORTIONS OF THE SOUTHERN TIER AROUND DAYBREAK...WITH THIS
AXIS LIKELY TO SLOWLY LIFT NORTH TO A BUFFALO TO WELLSVILLE LINE BY
EARLY AFTERNOON...THEN EVENTUALLY FURTHER NORTH AND EAST BY LATE
AFTERNOON. THIS PRECIPITATION WILL BE CONVECTIVE...WITH BUFKIT
SHOWING A MOIST SOUNDING WITH THIN AND NARROW CAPES...AND P-WAT
VALUES AROUND 1.6 INCHES. CONSENSUS QPFS FROM THE HIGHER RESOLUTION
MODELS INCLUDING RECENT RUNS OF THE NAM/RGEM/SREF ONLY AVERAGE
AROUND AN INCH WITH THIS. HOWEVER...GIVEN THE SLOW MOTION OF THE
CONVECTIVE CELLS...LOCALLY HIGHER AMOUNTS ARE POSSIBLE. YESTERDAY
EVENING SLOW MOVING SHOWERS RESULTED IN RADAR ESTIMATES OF OVER 3
INCHES IN A FEW SPOTS IN SOUTHERN ONTARIO PROVINCE. RAIN AMOUNTS IN EXCESS
OF TWO INCHES WOULD BE A CONCERN PRETTY MUCH ANYWHERE...WITH URBAN
AREAS...THE BUFFALO CREEKS...AND AREAS WITH RECENT RAINS VULNERABLE
TO LESSER RAINFALL AMOUNTS. FOLLOWING THIS...WILL KEEP THE FLOOD
WATCH UP IN WESTERN NEW YORK AS WELL.
THE UPPER LOW WILL GRADUALLY MOVE ACROSS THE REGION TONIGHT...WHICH
WILL EFFECTIVELY END THIS AXIS AS THE LOW BECOMES VERTICALLY
STACKED. THERE WILL BE A LINGERING THREAT FOR SHOWERS TONIGHT...WITH
SHOWERS EXPECTED TO BECOME INCREASINGLY SCATTERED IN NATURE AS THE
NIGHT GOES ON.
WHILE WIDESPREAD THUNDERSTORMS ARE NOT LIKELY...THERE MAY BE SOME
EMBEDDED IN AREAS OF HEAVY RAIN TODAY.
TEMPERATURES WILL NOT RISE VERY MUCH AT ALL TODAY...WITH PERSISTENT
CLOUDS COVER AND AREAS OF SHOWERS. EXPECT HIGHS TO ONLY BE AROUND 70
DEGREES IN MOST LOCATIONS. OVERNIGHT LOWS SHOULD DROP INTO THE UPPER
50S TO LOWER 60S. PATCHY FOG IS LIKELY...AND WHILE MOSTLY CLOUDY
SKIES ARE EXPECTED...ANY CLEARING WOULD QUICKLY FAIRLY DENSE FOG
DEVELOPMENT.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
A FULL LATITUDE TROUGH IS FORECAST TO REMAIN IN PLACE FROM SOUTHERN
QUEBEC TO THE TENNESSEE VALLEY THROUGH THIS PERIOD. THE DEEP LAYERED
SOUTHERLY FLOW WILL KEEP MOIST AND SOMEWHAT UNSTABLE AIR OVER OUR
AREA WHICH WILL LEAD TO OCCASIONAL SHOWERS AND SCATTERED
THUNDERSTORMS. THE MODELS AGREE THAT A LOW LEVEL TROUGH/BAROCLINIC
ZONE WILL REMAIN STALLED OVER CENTRAL NEW YORK STATE. THIS
BOUNDARY WILL HELP TO FOCUS THE MOISTURE WHICH COULD LEAD TO
ENHANCED RAINFALL AT TIMES. IN ADDITION...A SERIES OF SHORT WAVES
WILL BE LIFTING NORTH THROUGH THE EASTERN FLANK OF THE UPPER LEVEL
TROUGH...BUT THE TIMING OF THESE IMPULSES CANNOT BE PINNED DOWN AT
THIS TIME. AS A RESULT...WILL FOLLOW THE PREVIOUS TREND OF
INDICATING HIGHER POPS DURING THE AFTERNOON WHEN DAYTIME HEATING
WILL LEAD TO A BETTER CHANCE FOR A FEW THUNDERSTORMS. ALL OF THESE
FACTORS COULD LEAD TO A POTENTIAL FOR MORE FLOODING
ISSUES...ESPECIALLY WITH THE ANTECEDENT MOISTURE THAT WILL BE IN
PLACE FROM PREVIOUS RAINFALL.
ABUNDANT CLOUD COVER AND SHOWER ACTIVITY ALONG WITH SLIGHTLY COOLER
AIR ALOFT DUE TO THE PRESENCE OF THE UPPER LEVEL TROUGH WILL HELP
KEEP TEMPERATURES SLIGHTLY BELOW AVERAGE DURING THIS PERIOD.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
A DEEP UPPER LEVEL TROUGH EXTENDING FROM JAMES BAY ACROSS THE GREAT
LAKES DOWN TO THE CENTRAL GULF COAST WILL GRADUALLY RETROGRADE WEST
TO THE MISSISSIPPI VALLEY AS THE BERMUDA HIGH REASSERTS IT/S
DOMINANCE OVER THE WESTERN ATLANTIC. THE PRESENCE OF A DEEP LAYERED
SOUTHERLY FLOW AND AN ABUNDANT SUPPLY OF LOW LEVEL MOISTURE
WILL KEEP WESTERN AND NORTH CENTRAL NEW YORK IN A FAVORABLE POSITION
FOR UNSETTLED WEATHER THROUGH MUCH OF THE UPCOMING WEEK. THE BULK OF
PRECIPITATION WILL BE IN THE FORM OF DIURNALLY DRIVEN CONVECTION
WITH SHOWERS AND THUNDERSTORMS BREAKING OUT IN THE AFTERNOON AND
EVENING HOURS EACH DAY.
TEMPERATURES DURING THE PERIOD WILL SHOW A SLOW MODERATING TREND AS
THE UPPER LEVEL TROUGH SLIDES WEST AND SOMEWHAT WARMER AIR OVER THE
EAST COAST PUSHES BACK INTO THE LOWER GREAT LAKES.
&&
.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
OVERALL...A VERY LOW CONFIDENCE AVIATION FORECAST GIVEN THE
RATHER SPOTTY CONVECTION WHICH CAN TEMPORARILY LOWER CIGS/VSBY TO
IFR OR LOWER. AT 09Z...A PATCHY IFR CLOUD DECK WAS IMPACTING A FEW
SITES (ROC/JHW)...WHILE STEADIER RAIN LOWERED CIGS AT ART. STEADY
RAINS AT ART SHOULD END MID-MORNING WITH IMPROVING CONDITIONS AFTER
THIS.
ELSEWHERE...EXPECT SHOWERS TO EXPAND...RESULTING IN LOWERING
CIGS/VSBY AT BUF/IAG...AND SLIGHTLY IMPROVING CONDITIONS AT JHW.
THESE WILL EVENTUALLY SPREAD TO ROC LATE MORNING. CONDITIONS WILL
CONTINUE TO BE VARIABLE IN AND OUT OF SHOWERS. WITH MODEST
INSTABILITY IN PLACE...A WIDELY SCATTERED THUNDERSTORM CANNOT BE
RULED OUT AT ANY POINT TODAY...BUT WILL MOST LIKELY ACCOMPANY THE
HEAVIEST RAIN SHOWERS. SHOWERS WILL GRADUALLY TAPER OFF THIS
EVENING...BUT EVEN AS SHOWERS TAPER OFF SIGNIFICANT LOW MOISTURE
MAY RESULT IN MVFR OR LOWER CONDITIONS OVERNIGHT. CONDITIONS WILL
VARY...WITH ANY CLEARING ALOFT LIKELY TO BE QUICKLY FOLLOWED BY
LOW CIGS/VSBY.
OUTLOOK...
SATURDAY THROUGH TUESDAY...MAINLY VFR WITH A CHANCE OF MAINLY
AFTERNOON SHOWERS AND THUNDERSTORMS WITH ASSOCIATED BRIEF MVFR/IFR.
&&
.MARINE...
LOW PRESSURE TRACKING ACROSS NEW YORK STATE WILL CAUSE NNE WINDS TO
PICK UP THIS MORNING. CONDITIONS WILL BECOME A BIT CHOPPY...BUT
WAVES ARE EXPECTED TO REMAIN BELOW SCA CRITERIA. AFTER THIS WINDS
WILL DIMINISH...WITH NO HEADLINES ANTICIPATED FOR THIS WEEKEND.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...FLOOD WATCH THROUGH THIS EVENING FOR NYZ006>008.
FLOOD WATCH THROUGH THIS EVENING FOR NYZ001>005-010>014-
019>021-085.
MARINE...NONE.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL
SHORT TERM...TJP
LONG TERM...TJP/WOOD
AVIATION...APFFEL
MARINE...APFFEL/TJP
AREA FORECAST DISCUSSION
NWS BUFFALO NY
338 AM EDT FRI JUN 28 2013
.SYNOPSIS...
LOW PRESSURE WILL SLOWLY LIFT ACROSS EASTERN NEW YORK TODAY...WITH
THIS LOW EXPECTED TO STALL NEAR THE REGION AS IT GRADUALLY
WEAKENS THROUGH THE WEEKEND. THIS WILL BRING PERIODS OF RAIN
TODAY...WITH EMBEDDED AREAS OF HEAVIER RAIN AND THUNDERSTORMS.
THE THREAT FOR SHOWERS AND PERHAPS A THUNDERSTORM WILL PERSIST
THROUGH THE WEEKEND...HOWEVER SHOWERS WILL BECOME INCREASINGLY
SCATTERED AS THE WEEKEND WEARS ON.
&&
.NEAR TERM /THROUGH TONIGHT/...
THERE CONTINUES TO BE A POTENTIAL FOR FLOODING ACROSS PORTIONS OF
WESTERN NEW YORK TODAY. THERE APPEARS TO BE TWO MAIN FEATURES TO
WATCH TODAY...WITH THE MOST OBVIOUS BEING THE LARGE AREA OF RAIN
ASSOCIATED WITH THE WEAK SURFACE LOW WHICH IS LIFTING ACROSS EASTERN
NEW YORK STATE. RADAR TRENDS SUPPORT THE HRRR HANDLING OF THIS
FEATURE...WHICH LARGELY KEEPS THE CORE OF IT TO THE SOUTH AND EAST
OF OUR CWA. THIS SAID...EXPECT A RATHER QUICK INCH OF RAIN ACROSS
LEWIS COUNTY THROUGH MID-MORNING...WITH LESSER AMOUNTS TO THE WEST
IN JEFFERSON/OSWEGO COUNTIES. IF THIS HOLDS...WE PROBABLY WILL NOT
SEE FLOODING...HOWEVER GIVEN THE CLOSE PROXIMITY OF HEAVIER RAINS WE
WILL KEEP UP THE FLOOD WATCH. UPSTREAM RAINS WILL LIKELY CAUSE
WITHIN BANK RISES ON THE BLACK RIVER AT BOONVILLE.
THE SECOND FEATURE WE WILL BE KEEPING A CLOSE EYE ON IS A MORE
SUBTLE UPPER LEVEL TROF AXIS WHICH EXTENDS FROM WESTERN NEW YORK
BACK INTO SOUTHERN ONTARIO TO GEORGIAN BAY. SCATTERED...BUT VERY
SLOW MOVING...SHOWERS ALONG THIS AXIS ARE FORECAST TO EXPAND BY THE
HRRR. SEVERAL RUNS OF THE NAM/RGEM SUPPORT THE HRRR FORECAST...AND GIVEN
A FAIRLY GOOD TRACK RECORD FOR THIS EVENT...HAVE MODERATE CONFIDENCE
IN ITS FORECAST. EXPECT SHOWERS TO DEVELOP ALONG A NW-SE AXIS ACROSS
WESTERN PORTIONS OF THE SOUTHERN TIER AROUND DAYBREAK...WITH THIS
AXIS LIKELY TO SLOWLY LIFT NORTH TO A BUFFALO TO WELLSVILLE LINE BY
EARLY AFTERNOON...THEN EVENTUALLY FURTHER NORTH AND EAST BY LATE
AFTERNOON. THIS PRECIPITATION WILL BE CONVECTIVE...WITH BUFKIT
SHOWING A MOIST SOUNDING WITH THIN AND NARROW CAPES...AND P-WAT
VALUES AROUND 1.6 INCHES. CONSENSUS QPFS FROM THE HIGHER RESOLUTION
MODELS INCLUDING RECENT RUNS OF THE NAM/RGEM/SREF ONLY AVERAGE
AROUND AN INCH WITH THIS. HOWEVER...GIVEN THE SLOW MOTION OF THE
CONVECTIVE CELLS...LOCALLY HIGHER AMOUNTS ARE POSSIBLE. YESTERDAY
EVENING SLOW MOVING SHOWERS RESULTED IN RADAR ESTIMATES OF OVER 3
INCHES IN A FEW SPOTS IN SOUTHERN ONTARIO PROVINCE. RAIN AMOUNTS IN EXCESS
OF TWO INCHES WOULD BE A CONCERN PRETTY MUCH ANYWHERE...WITH URBAN
AREAS...THE BUFFALO CREEKS...AND AREAS WITH RECENT RAINS VULNERABLE
TO LESSER RAINFALL AMOUNTS. FOLLOWING THIS...WILL KEEP THE FLOOD
WATCH UP IN WESTERN NEW YORK AS WELL.
THE UPPER LOW WILL GRADUALLY MOVE ACROSS THE REGION TONIGHT...WHICH
WILL EFFECTIVELY END THIS AXIS AS THE LOW BECOMES VERTICALLY
STACKED. THERE WILL BE A LINGERING THREAT FOR SHOWERS TONIGHT...WITH
SHOWERS EXPECTED TO BECOME INCREASINGLY SCATTERED IN NATURE AS THE
NIGHT GOES ON.
WHILE WIDESPREAD THUNDERSTORMS ARE NOT LIKELY...THERE MAY BE SOME
EMBEDDED IN AREAS OF HEAVY RAIN TODAY.
TEMPERATURES WILL NOT RISE VERY MUCH AT ALL TODAY...WITH PERSISTENT
CLOUDS COVER AND AREAS OF SHOWERS. EXPECT HIGHS TO ONLY BE AROUND 70
DEGREES IN MOST LOCATIONS. OVERNIGHT LOWS SHOULD DROP INTO THE UPPER
50S TO LOWER 60S. PATCHY FOG IS LIKELY...AND WHILE MOSTLY CLOUDY
SKIES ARE EXPECTED...ANY CLEARING WOULD QUICKLY FAIRLY DENSE FOG
DEVELOPMENT.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
A FULL LATITUDE TROUGH IS FORECAST TO REMAIN IN PLACE FROM SOUTHERN
QUEBEC TO THE TENNESSEE VALLEY THROUGH THIS PERIOD. THE DEEP LAYERED
SOUTHERLY FLOW WILL KEEP MOIST AND SOMEWHAT UNSTABLE AIR OVER OUR
AREA WHICH WILL LEAD TO OCCASIONAL SHOWERS AND SCATTERED
THUNDERSTORMS. THE MODELS AGREE THAT A LOW LEVEL TROUGH/BAROCLINIC
ZONE WILL REMAIN STALLED OVER CENTRAL NEW YORK STATE. THIS
BOUNDARY WILL HELP TO FOCUS THE MOISTURE WHICH COULD LEAD TO
ENHANCED RAINFALL AT TIMES. IN ADDITION...A SERIES OF SHORT WAVES
WILL BE LIFTING NORTH THROUGH THE EASTERN FLANK OF THE UPPER LEVEL
TROUGH...BUT THE TIMING OF THESE IMPULSES CANNOT BE PINNED DOWN AT
THIS TIME. AS A RESULT...WILL FOLLOW THE PREVIOUS TREND OF
INDICATING HIGHER POPS DURING THE AFTERNOON WHEN DAYTIME HEATING
WILL LEAD TO A BETTER CHANCE FOR A FEW THUNDERSTORMS. ALL OF THESE
FACTORS COULD LEAD TO A POTENTIAL FOR MORE FLOODING
ISSUES...ESPECIALLY WITH THE ANTECEDENT MOISTURE THAT WILL BE IN
PLACE FROM PREVIOUS RAINFALL.
ABUNDANT CLOUD COVER AND SHOWER ACTIVITY ALONG WITH SLIGHTLY COOLER
AIR ALOFT DUE TO THE PRESENCE OF THE UPPER LEVEL TROUGH WILL HELP
KEEP TEMPERATURES SLIGHTLY BELOW AVERAGE DURING THIS PERIOD.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
A DEEP UPPER LEVEL TROUGH EXTENDING FROM JAMES BAY ACROSS THE GREAT
LAKES DOWN TO THE CENTRAL GULF COAST WILL GRADUALLY RETROGRADE WEST
TO THE MISSISSIPPI VALLEY AS THE BERMUDA HIGH REASSERTS IT/S
DOMINANCE OVER THE WESTERN ATLANTIC. THE PRESENCE OF A DEEP LAYERED
SOUTHERLY FLOW AND AN ABUNDANT SUPPLY OF LOW LEVEL MOISTURE
WILL KEEP WESTERN AND NORTH CENTRAL NEW YORK IN A FAVORABLE POSITION
FOR UNSETTLED WEATHER THROUGH MUCH OF THE UPCOMING WEEK. THE BULK OF
PRECIPITATION WILL BE IN THE FORM OF DIURNALLY DRIVEN CONVECTION
WITH SHOWERS AND THUNDERSTORMS BREAKING OUT IN THE AFTERNOON AND
EVENING HOURS EACH DAY.
TEMPERATURES DURING THE PERIOD WILL SHOW A SLOW MODERATING TREND AS
THE UPPER LEVEL TROUGH SLIDES WEST AND SOMEWHAT WARMER AIR OVER THE
EAST COAST PUSHES BACK INTO THE LOWER GREAT LAKES.
&&
.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
OVERALL...A VERY LOW CONFIDENCE AVIATION FORECAST GIVEN THE RATHER
SPOTTY CONVECTION WHICH CAN TEMPORARILY LOWER CIGS/VSBY TO IFR OR
LOWER. OUTSIDE OF THIS...CONDITIONS ARE MAINLY VFR AT
06Z...OUTSIDE OF PATCHY AREAS OF DENSE FOG AND VLIFR CIGS. THIS
TREND IS LIKELY TO CONTINUE THROUGH THE EARLY MORNING
HOURS...EXCEPT THAT STEADIER RAIN SHOWERS ARE LIKELY TO DEVELOP
ACROSS WESTERN AREAS FROM JHW TO BUF/IAG...AND EVENTUALLY ROC. THIS
SHOULD LEAD TO LOWERING CONDITIONS DURING THE MORNING HOURS. ART IS
A DIFFERENT STORY WITH STEADIER RAINS LIKELY TO BACK IN FROM THE
EAST OVERNIGHT.
DURING THE DAYTIME HOURS...SHOWERS SHOULD BECOME A BIT MORE
SCATTERED IN NATURE...EVENTUALLY TAPERING OFF DURING THE EVENING
HOURS. WITH MODEST INSTABILITY IN PLACE...A WIDELY SCATTERED
THUNDERSTORM CANNOT BE RULED OUT AT ANY POINT TODAY...BUT WILL
MOST LIKELY ACCOMPANY THE HEAVIEST RAIN SHOWERS. EVEN AS SHOWERS
TAPER OFF...SIGNIFICANT LOW MOISTURE MAY RESULT IN MVFR OR LOWER
CONDITIONS OVERNIGHT. CONDITIONS WILL VARY...WITH ANY CLEARING
ALOFT LIKELY TO BE QUICKLY FOLLOWED BY LOW CIGS/VSBY.
OUTLOOK...
SATURDAY THROUGH TUESDAY...MAINLY VFR WITH A CHANCE OF MAINLY
AFTERNOON SHOWERS AND THUNDERSTORMS WITH ASSOCIATED BRIEF MVFR/IFR.
&&
.MARINE...
LOW PRESSURE TRACKING ACROSS NEW YORK STATE WILL CAUSE NNE WINDS TO
PICK UP THIS MORNING. CONDITIONS WILL BECOME A BIT CHOPPY...BUT
WAVES ARE EXPECTED TO REMAIN BELOW SCA CRITERIA. AFTER THIS WINDS
WILL DIMINISH...WITH NO HEADLINES ANTICIPATED FOR THIS WEEKEND.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...FLOOD WATCH THROUGH THIS EVENING FOR NYZ006>008.
FLOOD WATCH THROUGH THIS EVENING FOR NYZ001>005-010>014-
019>021-085.
MARINE...NONE.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL
SHORT TERM...TJP
LONG TERM...TJP/WOOD
AVIATION...APFFEL
MARINE...APFFEL/TJP
AREA FORECAST DISCUSSION
NWS RALEIGH NC
142 AM EDT FRI 28 2013
.SYNOPSIS...
A WARM AND HUMID AIR MASS WILL HOLD OVER THE REGION FOR THE NEXT
SEVERAL DAYS... AS A LARGE LOW PRESSURE TROUGH HOLDS OVER THE
EASTERN HALF OF THE COUNTRY. PASSING UPPER LEVEL DISTURBANCES WILL
HELP PRODUCE NUMEROUS SHOWERS AND THUNDERSTORMS EACH DAY THROUGH THE
UPCOMING WEEKEND.
&&
.NEAR TERM /THROUGH FRIDAY NIGHT/...
AS OF 935 PM THURSDAY...
THE LAST CLUSTER OF ORGANIZED CONVECTION CONTINUES MOVING TO THE ESE
OVER THE SRN PIEDMONT AND SW SANDHILLS. OTHER MORE ISOLATED CELLS
ELSEWHERE HAVE BECOME STRONG BUT THEIR HIGH-REFLECTIVITY CORES HAVE
NOT QUITE REACHED THE HEIGHTS OF EARLIER STORMS. THE BOUNDARY LAYER
CONTINUES TO SLOWLY BUT STEADILY STABILIZE WITH MLCAPE DOWN TO 1500
J/KG AND GROWING CINH... AND THIS TREND SHOULD CONTINUE WITH STORMS
DISSIPATING IN THE NEXT FEW HOURS. THE LATEST COUPLE OF HRRR RUNS AS
WELL AS THE SREF AND WRF SUPPORT THIS SCENARIO WITH REMAINING STORMS
SHIFTING TO OUR EAST AND WEAKENING. DYNAMIC SUPPORT FOR ASCENT WILL
BE WANING AS THE VORTICITY AXIS SHIFTS TO OUR EAST... LEAVING BEHIND
BAGGY MID LEVEL TROUGHING OVERNIGHT WITH A LINGERING DIFFUSE TROUGH
AT THE SURFACE THROUGH THE CENTRAL CAROLINAS. WILL HOLD ONTO
EXISTING FORECAST TREND OF POPS DECREASING WEST TO EAST. EXPECT FAIR
TO PARTLY CLOUDY SKIES OVERNIGHT... ALTHOUGH THE MORE WIDESPREAD
SHOWERS/STORMS IN THE EAST ALONG WITH SLIGHTLY HIGHER DEW POINTS AND
925-850 MB MOISTURE SHOULD YIELD MORE WIDESPREAD STRATUS IN OUR
EAST. WITH THE RAIN-COOLED AIR IN SOME AREAS... CURRENT TEMPS HAVE
FALLEN TO WITHIN A FEW DEGREES OF THE DEW POINT AND HENCE ARE CLOSE
TO THE NIGHTTIME LOWS. CURRENT TEMP TRENDS PLUS STATISTICAL GUIDANCE
SUPPORT LOWS CLOSE TO THE CURRENT FORECAST OF 69-74. -GIH
FRIDAY...
SHORTWAVE ENERGY DIGGING THROUGH THE UPPER MIDWEST WILL CONTINUE TO
DEEPEN THE UPPER LEVEL TROUGH DEVELOPING OVER THE EASTERN US. A
SHARP PIEDMONT TROUGH WILL BE IN PLACE DURING THE DAY ON
FRIDAY..WITH LITTLE CHANGE IN AIRMASS EXPECTED OUTSIDE OF SLIGHTLY
LOWER DEWPOINTS IN THE WESTERN PIEDMONT. CYCLONIC FLOW
ALOFT...ALBEIT WITHOUT A NOTABLE TRIGGER IN THE MODELS...AND MODEST
INSTABILITY WILL ONCE AGAIN SUPPORT SCATTERED TO NUMEROUS
THUNDERSTORMS DURING THE AFTERNOON. WHILE ITS POSSIBLE THAT
COVERAGE MAY NOT BE AS GREAT AS THIS AFTERNOON...MID-LEVEL FLOW WILL
BE STRONGER AND DEEP LAYER SHEAR IS PROGGED TO TO EXCEED
30KT...SUGGESTING MULTICELLULAR ORGANIZATION. THE CURRENT SPC DAY
TWO OUTLOOK INCLUDES ALL OF CENTRAL NC IN A SLIGHT RISK.
REGARDING HIGH TEMPS...GUIDANCE ALMOST UNANIMOUSLY GIVES VALUES A
FEW DEGREES WARM THAN TODAY...WITH LOWER 90S ACROSS A LARGE PORTION
OF THE CWA. THIS WILL LIKELY LEAD TO HEAT INDICES NEAR 100 ACROSS
THE SANDHILLS AND SOUTHERN PIEDMONT WHERE DEWPOINTS SHOULD HOVER IN
THE LOWER 70S.
FRIDAY NIGHT...
WILL CONTINUE AT LEAST A SLIGHT CHANCE OF SHOWERS AND STORMS THROUGH
FRIDAY NIGHT AS HEIGHTS CONTINUE TO SLOWLY FALL ALOFT AND THE
AIRMASS OVER NC REMAINS HUMID. LOWS IN THE UPPER 60S AND LOWER 70S.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300 PM THURSDAY...
AN ANOMALOUSLY AMPLIFIED PATTERN WILL PREVAIL ACROSS THE CONUS
THROUGH THE WEEKEND...CHARACTERIZED BY A DEEP UPPER LEVEL RIDGE OVER
THE ROCKIES/INTERMOUNTAIN WEST AND DEEP TROUGHING EAST OF THE
MISSISSIPPI...WITH A PERSISTENT UPPER LEVEL LOW CENTERED IN VICINITY
OF THE LOWER GREAT LAKES AND OH VALLEY. ACROSS THE CAROLINAS AND
MID-ATLANTIC...EXPECT ATYPICALLY STRONG SOUTHWEST FLOW ALOFT WITH
NUMEROUS SMALL AMPLITUDE SHORTWAVES CROSSING THE REGION THROUGHOUT
THE PERIOD IN THE PRESENCE OF A SEASONABLY MOIST AIRMASS. AS A
RESULT...EXPECT ABOVE NORMAL CHANCES FOR SHOWERS AND THUNDERSTORMS
AND SLIGHTLY BELOW NORMAL HIGH TEMPS IN THE MID 80S...DEPENDING ON
CLOUD COVER AND CONVECTION. THE EXACT COVERAGE AND PERSISTENCE OF
CONVECTION WILL HIGHLY DEPEND ON THE EVOLUTION OF SMALL AMPLITUDE
DISTURBANCES IN SW FLOW ALOFT AND THE TIMING OF THESE DISTURBANCES
IN RELATION TO THE DIURNAL HEATING CYCLE. FURTHERMORE...THE DEGREE
OF DIURNAL DESTABILIZATION IS DIFFICULT TO ASCERTAIN GIVEN INCREASED
CLOUD COVER AND AN ABOVE NORMAL CHANCE FOR NOCTURNAL OR EARLY
MORNING CONVECTION...THOUGH ONE WOULD EXPECT AT LEAST SOME CLOUD
BREAKS AND AREAS OF RELATIVELY STRONGER INSOLATION DURING PEAK
HEATING. EITHER WAY...SLIGHTLY STEEPER MID-LEVEL LAPSE RATES /COOLER
TEMPS ALOFT/ IN ASSOCIATION WITH THE UNUSUALLY AMPLIFIED UPPER LEVEL
TROUGH OVER THE REGION WILL AT LEAST SOMEWHAT COMPENSATE FOR
DECREASED INSOLATION. GIVEN DEEP-LAYER (0-6 KM) SHEAR LIKELY IN THE
35-45 KT RANGE...ORGANIZED CONVECTION WILL CERTAINLY BE POSSIBLE...
INCLUDING SUPERCELLS...THOUGH THE TYPE/EXTENT OF ANY SEVERE THREAT
CANNOT BE PRECISELY IDENTIFIED AT THIS TIME. IN ADDITION TO A
POTENTIAL FOR SEVERE THUNDERSTORMS...ISOLATED FLASH FLOODING WILL
ALSO BE POSSIBLE GIVEN RECENT HEAVY RAINFALL AND ABOVE NORMAL
CHANCES FOR CONVECTION THROUGH THE WEEKEND. -VINCENT
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300 PM THURSDAY...
AN UNSEASONABLY AMPLIFIED UPPER LEVEL PATTERN WILL PERSIST ACROSS
THE CONUS THROUGH THE MIDDLE OF NEXT WEEK...CHARACTERIZED BY RIDGING
OVER THE INTERMOUNTAIN WEST...TROUGHING CENTERED IN VICINITY OF THE
MS RIVER VALLEY AND ATYPICALLY STRONG SW FLOW ALOFT OVER THE
CAROLINAS. NUMEROUS SMALL AMPLITUDE DISTURBANCES IN THE PRESENCE OF
ABOVE NORMAL MOISTURE (PWAT ~2.00") WILL RESULT IN ABOVE NORMAL
CHANCES FOR SHOWERS AND THUNDERSTORMS THROUGH EARLY/MID NEXT WEEK...
MODULATED PRIMARILY BY THE DIURNAL HEATING CYCLE...IN ADDITION TO A
CONTINUED THREAT FOR SEVERE WEATHER (GIVEN FAVORABLE DEEP-LAYER
SHEAR) AND ISOLD FLASH FLOODING. IN GENERAL EXPECT HIGHS SEVERAL
DEGREES BELOW NORMAL DUE TO INCREASED CLOUD COVER AND CHANCES FOR
CONVECTION. -VINCENT
&&
.AVIATION /06Z THURSDAY THROUGH TUESDAY/...
AS OF 145 AM FRIDAY...
UPPER S/W VORT DISTURBANCE AND ASSOCIATED CONVECTION WILL EXIT THE
SANDHILLS AND SOUTHERN COASTAL COUNTIES BY 08Z WITH SUBSIDENCE IN
THE WAKE OF THE UPPER DISTURBANCE ALLOWING FOR DRY CONDITIONS FOR
THE SECOND PART OF THE NIGHT. PATCHY SUB-VFR STRATUS AND/OR FOG
IS POSSIBLE AROUND DAYBREAK...PARTICULARLY IN AREAS THAT SAW HEAVY
RAIN THIS PAST EVENING.
ANY STRATUS/FOG SHOULD LIFT BY 15Z THIS MORNING... WITH
PREDOMINATELY VFR CONDITIONS INTO THE EARLY AFTERNOON BEFORE
ANOTHER ROUND OF SCATTERED TO NUMEROUS STORMS ARE EXPECTED
OVER CENTRAL NC.
LOOKING BEYOND FRIDAY...THE WEATHER PATTERN WILL CHANGE VERY LITTLE
THE NEXT SEVERAL DAYS. AN UNSEASONABLY STRONG LOW PRESSURE TROUGH
COMBINED WITH A WARM AND UNSTABLE AIR WILL RESULT IN SCATTER TO
NUMEROUS SHOWERS AND STORMS EACH AFTERNOON/EARLY EVENING... AND
THE POTENTIAL FOR STRATUS OR FOG EACH MORNING.
&&
.EQUIPMENT...
KRAX WSR-88D WILL BE REMAIN DOWN OR IN DEGRADED MODE THROUGH FRIDAY
MORNING. KRAX HAS BEEN IN A SEVERELY DEGRADED MODE FOR SEVERAL
DAYS... AND THE NEEDED REPAIRS WERE DEEMED TO BE CRITICAL. THE TEAM
OF TECHNICIANS WILL MAKE THESE REPAIRS AS QUICKLY AS POSSIBLE... AND
IS WORKING TO RETURN THE RADAR TO NORMAL SERVICE BY EARLY AFTERNOON
FRIDAY. WE APOLOGIZE FOR THE INCONVENIENCE. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD/BLS
SHORT TERM...VINCENT
LONG TERM...VINCENT
AVIATION...CBL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
144 AM EDT FRI JUN 28 2013
.SYNOPSIS...
UNSETTLED WEATHER WILL CONTINUE THROUGH THE MIDDLE OF NEXT WEEK WITH
A DAILY RISK OF SHOWERS AND THUNDERSTORMS. SIGNIFICANT RAINFALL
AMOUNTS ARE EXPECTED THROUGH THE PERIOD AND THIS RAIN WILL BE
FALLING ON ALREADY WET SOILS.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1030 PM THURSDAY...THE LAST IN THE SERIES OF SHORTWAVE
DISTURBANCES ALOFT WILL PUSH ACROSS THE EASTERN CAROLINAS IN THE
NEXT SEVERAL HOURS...LIKELY SUSTAINING CONVECTION ACROSS THE AREA
THROUGH MIDNIGHT AND PERHAPS BEYOND. WITH SUCH A HUMID AIRMASS
(PRECIPITABLE WATER 2.0 TO 2.1 INCHES AND SURFACE DEWPOINTS IN THE
70S) VIRTUALLY ANY STORM CELL IS PRODUCING RAINFALL RATES IN EXCESS
OF 1 INCH PER HOUR. BASED MAINLY ON CURRENTLY OBSERVED RADAR TRENDS
I HAVE ADJUSTED POPS UP FOR THE NEXT 3-4 HOURS TO 100 PERCENT FROM
EASTERN COLUMBUS COUNTY THROUGH THE WILMINGTON METRO AREA...AND JUST
SOUTH OF FLORENCE TO NEAR KINGSTREE. THIS ACTIVITY IS PROBABLY NO
LONGER SURFACE BASED BUT IS TAKING ADVANTAGE OF A STRENGTHENING LOW
LEVEL JET WHICH IS ADVECTING IN EXTREMELY HUMID AIR OFF THE ATLANTIC
WITH DEWPOINTS IN THE UPPER 70S. FLOOD ADVISORIES OR WARNINGS MAY
NEED TO BE ISSUED IN THE NEXT HOUR OR TWO GIVEN THE SLOW OBSERVED
CELL MOTION COUPLED WITH HIGH RAINFALL RATES. PREVIOUS DISCUSSION
FROM 730 PM FOLLOWS...
A SERIES OF TWO UPPER LEVEL DISTURBANCES ROLLING ACROSS A
STRONGLY UNSTABLE AIRMASS LED TO THE DEVELOPMENT OF WIDESPREAD
THUNDERSTORMS THIS AFTERNOON. SURFACE-BASED INSTABILITY IS NOW
WANING WITH THE LOSS OF INSOLATION AND THE LARGE-SCALE OVERTURNING
OF THE AIRMASS. HOWEVER CONSIDERABLE INSTABILITY (CAPE: 3000 J/KG)
REMAINS SOUTH AND WEST OF FLORENCE WITH LESSER INSTABILITY ALONG
THE COAST FROM MYRTLE BEACH THROUGH WILMINGTON. (A SMALL NEGATIVE
REGION OF CONVECTIVE INHIBITION ALONG THE COAST COULD PREVENT THIS
INSTABILITY FROM BEING REALIZED)
SYNOPTIC MODELS ARE OFTEN OF LITTLE USE IN FORECASTING CONVECTION.
THE HRRR HIGH-RESOLUTION MODEL IS HAVING TROUBLE INITIALIZING THE
STORM PROPERLY BUT THE LAST SEVERAL RUNS SUGGEST THE INSTABILITY
SOUTH OF FLORENCE TOWARD THE SANTEE RIVER INTO THE CHARLESTON METRO
AREA WILL BE THE BREEDING GROUND FOR ANOTHER CLUSTER OF CONVECTION
OVER THE NEXT SEVERAL HOURS. THE FINAL UPPER LEVEL SHORTWAVE MOVING
SOUTHEAST THROUGH THE PIEDMONT REGION COULD ALSO IGNITE NEW STORMS
ACROSS THE SANDHILLS IN THE NEXT FEW HOURS WITH THE INTERSTATE 95
CORRIDOR POTENTIALLY RECEIVING ANOTHER ROUND OF ACTIVITY.
IN TERMS OF FORECAST POPS...I HAVE THE HIGHEST POPS FOR THE NEXT FEW
HOURS ACROSS NORTHERN ROBESON INTO BLADEN COUNTIES IN NC. BY LATE
THIS EVENING I SHIFT THE BULLSEYE SOUTHWARD FROM JUST INLAND OF
GEORGETOWN ACROSS CENTRAL HORRY COUNTY TO NEAR WILMINGTON. (50-60
PERCENT) AFTER MIDNIGHT MOST OF THE CONVECTIVE ACTIVITY SHOULD SHIFT
OFFSHORE BEHIND THE FINAL SHORTWAVE ALOFT...WITH DRYING CONDITIONS
TEMPORARILY BUILDING IN FROM THE WEST. I SAY TEMPORARILY BECAUSE THE
PATTERN FOR TOMORROW AFTERNOON THROUGH THE WEEKEND IS WET TO SAY THE
LEAST!
FORECAST LOWS TONIGHT RANGE FROM 72-77...COOLEST WEST OF I-95 AND
WARMEST ALONG THE COAST.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY NIGHT/...
AS OF 3 PM THURSDAY...A BROAD UPPER LOW ACROSS THE GREAT LAKES WILL
SLOWLY RELOCATE ACROSS THE OHIO VALLEY DURING THIS PERIOD. MID-LEVEL
SHORTWAVE ENERGY ROTATING AROUND THE UPPER LOW WILL HELP TO ENHANCE
SHOWERS AND THUNDERSTORMS. SURFACE FEATURES THAT WILL HELP TO
CONVERGE AND LIFT A MOIST AND UNSTABLE AIRMASS INCLUDE THE SEABREEZE
AND THE PIEDMONT TROUGH. OVERALL...A WET PERIOD IS IN STORE WITH
BOUTS OF SHOWERS AND THUNDERSTORMS. RAINFALL AMOUNTS JUST DURING
THIS PERIOD WILL LIKELY ADD ANOTHER 1 TO 2 INCHES TO WHAT HAS BEEN A
VERY WET JUNE ALREADY. AS IS USUALLY THE CASE WITH CONVECTION...SOME
SPOTS COULD RECEIVE AMOUNTS CONSIDERABLY HIGHER THAN THIS RANGE.
IT LOOKS AS THOUGH ONE SUCH SHORTWAVE WILL LIFT OUT ACROSS THE
EASTERN CAROLINAS DURING FRI AFTERNOON. MIXED LAYER CAPE VALUES ARE
VERY HIGH ON FRI...REACHING 3000 J/KG. MID-LEVEL LAPSE RATES ARE
HOWEVER MODEST. THE FLOW IS LARGELY WESTERLY...EXCEPT SW IN THE
LOWEST 3-5 KFT OR SO. THERE IS CONSIDERABLE DRY AIR IN THE
MID-LEVELS FRI MORNING...BUT THEN OVERTIME...THE COLUMN MOISTENS
FROM W TO E...DURING THE AFTERNOON AND EVE. THUS...THE SCENARIO
PAINTED BY SEVERAL OF THE MODELS LOOKS REASONABLE...SHOWERS AND
THUNDERSTORMS DEVELOPING ALONG THE PIEDMONT TROUGH IN RESPONSE TO
STRONG HEATING AND MOVING ACROSS OUR WESTERN ZONES FRI AFTERNOON AND
THEN TO THE COAST FRI EVE/NIGHT. A FEW STORMS MAY ALSO POP ALONG THE
SEABREEZE FRI AFTERNOON. GIVEN THE MAGNITUDE OF INSTABILITY AND
DEVELOPING INVERTED V SOUNDINGS...THERE IS A RISK FOR STRONG TO
POSSIBLY DAMAGING WINDS IN THE DEEPEST CONVECTION. MID-LEVEL TEMPS
SHOULD BE COOL ENOUGH TO SUPPORT HAIL IN ANY STRONG AND PERSISTENT
UPDRAFTS. THIS IS IN ADDITION TO THE HEAVY RAIN AND FREQUENT DEADLY
LIGHTING RISK. THE CONVECTION SHOULD ONLY SLOWLY WANE WITH LOSS OF
HEATING THROUGH THE LATE EVE AND OVERNIGHT.
SAT...THE FLOW TURNS MORE SOUTHWESTERLY THROUGH A DEEP LAYER AND
THERE IS NO DRY AIR IN THE COLUMN TO BE FOUND. THE COLUMN IS
SATURATED OR NEARLY SO THROUGH A DEEP LAYER. SOME OF THE MODELS ARE
INDICATING A SHORTWAVE TROUGH MOVING UP THE COAST...BUT A GOOD
DISTANCE OFFSHORE. WE WILL HAVE TO WATCH THIS FEATURE TO SEE HOW IT
EVENTUALLY PLAYS OUT. THERE MAY BE SOME SUBSIDENCE DEVELOPING ON THE
BACK SIDE WHICH WOULD TEND TO SUPPRESS/REDUCE CONVECTION.
HOWEVER...CLOSER TO THE COAST AND THERE COULD BE CONSIDERABLE
CONVECTION AT AND NEAR THE COAST. GIVEN THE ENVIRONMENT...IT WILL
TAKE VERY LITTLE TO IGNITE CONVECTION. STORM MOTIONS SHOULD BE MUCH
QUICKER ON SAT THAN ON FRI AS THE WIND FIELDS WILL BE STRONGER. WET
MICROBURSTS CAN NOT BE RULED OUT ON SAT.
CLOUD COVER SHOULD BE MORE WIDESPREAD SAT THAN ON FRI GIVEN THE
EXPECTED MOISTURE PROFILES. WILL THUS FORECAST HIGHER TEMPS ON
FRI...LOWER TO MID 90S. THE SEABREEZE SHOULD BE PINNED NEAR THE
COAST AND SO EVEN THE BEACHES SHOULD REACH THE UPPER 80S WITH THE
EXCEPTION OF BRUNSWICK AND SOUTHERN NEW HANOVER COUNTIES WHERE A
MORE ONSHORE FLOW SHOULD KEEP AFTERNOON TEMPS IN THE MID 80S. HIGHS
ON SAT WILL BE MAINLY IN THE UPPER 80S TO AROUND 90 WELL INLAND WITH
MID 80S AT THE BEACHES AS THE SEABREEZE SHOULD BE ABLE TO MAKE A
LITTLE FURTHER PROGRESS INLAND. LOWS WILL BE IN THE MUGGY 70S.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 3 PM THURSDAY...ACTIVE WEATHER WILL CONTINUE THROUGH AT
LEAST THE FIRST HALF OF THE WEEK. MID TO UPPER TROUGH DIGGING DOWN
THROUGH THE MISSISSIPPI VALLEY ON SUNDAY WILL LIFT TOWARD THE
NORTHWEST AS STRONG UPPER RIDGE TO OUR EAST TRIES TO BUILD
WESTWARD ACROSS THE EAST COAST. INITIALLY LOCAL AREA WILL REMAIN
BETWEEN THESE TWO FEATURES ON THE ACTIVE SIDE OF MID TO UPPER
TROUGH. SHORTWAVE ENERGY WILL ROTATE AROUND THE TROUGH UP THROUGH
THE CAROLINAS ENHANCING LOCALIZED CONVECTION SUNDAY THROUGH MID
WEEK. THE CONVECTION SHOULD FIRST FIRE UP OVER THE SEA BREEZE
CONVERGENT BOUNDARY AND THE PIEDMONT TROUGH INLAND BUT THEN WILL
BECOME MORE WIDESPREAD ALONG MESO OUTFLOW BOUNDARIES. OVERALL WILL
REMAIN IN DEEP MOIST SOUTHERLY FLOW AND EXPECT PLENTY OF CLOUDS
AND CONVECTION EACH DAY IN A WARM AND HUMID SUMMERTIME AIR MASS.
THE STEERING FLOW WILL KEEP STORMS MOVING FROM SOUTH TO NORTH AND
MAY ALLOW FOR BETTER WEATHER ALONG THE IMMEDIATE COAST.
AS MID TO UPPER TROUGH LIFTS FARTHER NORTH INTO CANADA THE RIDGE MAY
MAKE IT FAR ENOUGH WEST TO PROVIDE SOME SUBSIDENCE AND DRYING
THROUGH THE MID LEVELS OF THE ATMOSPHERE BY WED OR THURS. WITHOUT
THE UPPER LEVEL SUPPORT WE CAN GET BACK TO LESS IN THE WAY OF
STRONGER CONVECTION AND JUST LOCALIZED SHOWER ACTIVITY ALONG THE SEA
BREEZE AND PIEDMONT TROUGH.
TEMPS WILL RUN NEAR OR ABOVE NORMAL THROUGH THE PERIOD WITH 70S FOR
OVERNIGHT LOWS AND CLOSE TO 90 FOR AFTERNOON HIGHS.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 06Z...SLOWLY WEAKENING SHOWERS AND ISOLATED THUNDERSTORMS
WITH HEAVY RAINFALL WILL CONTINUE ACROSS THE INLAND TERMINALS
EARLY THIS MORNING. THE ACTIVITY WILL WEAKEN AS IT PUSHES TOWARD THE
COAST AND ACROSS AN AREA THATS BEEN WORKED OVER EARLIER BY
CONVECTION. TEMPO MVFR CONDITIONS WILL BE NEEDED WITH THIS
ACTIVITY. IFR/LIFR CONDITIONS AS WELL AS VARIABLE WIND GUSTS TO 30
KTS WILL OCCUR IF A THUNDERSTORM MOVES DIRECTLY OVER ANY TERMINAL.
CONVECTION WILL GRADUALLY DECREASE IN COVERAGE THROUGH SUNRISE.
THERE IS MODERATE CONFIDENCE IFR CIGS/MVFR VSBYS WILL DEVELOP AT
KFLO/KLBT 08-12Z. COASTAL TERMINALS SHOULD REMAIN VFR OUTSIDE OF
PRECIPITATION AREAS. SHOWERS SHOULD BE MAINLY OFFSHORE AFTER
SUNRISE...BUT REDEVELOPMENT ALONG THE SEA BREEZE MID-LATE MORNING
AND NEAR KFLO/KLBT...EAST OF THE PIEDMONT TROF...DURING THE
AFTERNOON IS EXPECTED. VFR EXPECTED OUTSIDE OF PRECIPITATION
AREAS.
EXTENDED OUTLOOK...ISOLATED/SCATTERED AFTERNOON SHOWERS AND
THUNDERSTORMS THROUGH TUESDAY WITH BRIEF LOCALIZED PERIODS OF
MVFR/IFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 PM THURSDAY...NEW THUNDERSTORMS ARE MOVING OFF THE COAST
NORTH OF CAPE FEAR. THESE STORMS MAY BE FOLLOWED BY MORE WAVES OF
STORMS OVERNIGHT AS ANOTHER UPPER LEVEL DISTURBANCE PUSHES OFF THE
COAST. THE UPDATED FORECAST FEATURES INCREASED THUNDERSTORM
POTENTIAL THROUGH ABOUT 2-3 AM FRIDAY...WITH LESSENING CHANCES LATE
TONIGHT. ALTHOUGH SYNOPTIC-SCALE WINDS WILL REMAIN FROM THE
SOUTHWEST AT 15-25 KNOTS...OBVIOUSLY THUNDERSTORM-SCALE WINDS MUCH
TOO SMALL TO FORECAST MORE THAN 1-2 HOURS IN ADVANCE WILL DOMINATE
THE WEATHER THROUGH THE NIGHT. MARINERS SHOULD CLOSELY WATCH FOR
THESE STORMS AS THEY ARE PRODUCING CONTINUOUS LIGHTNING...
TORRENTIAL RAINFALL AND REDUCED VISIBILITIES...AND STRONG GUSTY
WINDS. PREVIOUS DISCUSSION FROM 730 PM FOLLOWS...
A FAIRLY TIGHT PRESSURE GRADIENT EXISTS BETWEEN A PIEDMONT TROUGH
NEARLY STATIONARY INLAND AND THE BERMUDA HIGH WELL OFFSHORE. THIS IS
PRODUCING A HEALTHY SOUTH-SOUTHWEST BREEZE AT 15-25 KNOTS THIS
EVENING. ALTHOUGH MODELS SUGGEST WIND SPEEDS WILL RELAX A LITTLE
AFTER MIDNIGHT...THE TIGHT GRADIENT SHOULD REMAIN WITH STRONGER
WINDS REDEVELOPING FRIDAY. SEVERAL CLUSTERS OF THUNDERSTORMS INLAND
ARE WEAKENING AS THEY APPROACH THE COAST...BUT THE POTENTIAL REMAINS
FOR REDEVELOPMENT OF SHOWERS AND STORMS ACROSS THE COASTAL
WATERS...MAINLY FROM LATE THIS EVENING THROUGH ABOUT 3 AM FRIDAY.
THUNDERSTORMS CHANCES ARE SLIGHTLY HIGHER NORTH OF MYRTLE BEACH BUT
I CAN`T RULE OUT STORMS ACROSS THE SC WATERS EITHER.
I HAVE MADE SUBSTANTIAL EDITS TO SEA HEIGHTS BASED ON DATA FROM THE
OCEAN CREST PIER WAVE GAUGE WHICH IS REPORTING 3-4 FT SEAS JUST
OUTSIDE THE SURF ZONE. LARGER SEAS OFTEN PENETRATE RIGHT UP TO THE
BEACHES ON A GOOD ONSHORE WIND HERE...AN EFFECT EVEN OUR HIGH
RESOLUTION "SWAN" WAVE MODEL DOESN`T SEEM TO BE ABLE TO HANDLE.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 PM THURSDAY...A SMALL CRAFT ADVISORY HAS BEEN EXTENDED FOR
ALL AREAS UNTIL 6 PM SAT. THE PRESSURE GRADIENT BETWEEN A PIEDMONT
TROUGH INLAND AND THE BERMUDA RIDGE WILL HELP TO KEEP WINDS AND
SEAS ELEVATED THIS PERIOD. WINDS WILL REACH UP TO 20 TO 25 KT.
WINDS WILL BE SW THROUGH THE PERIOD...SLIGHTLY MORE W OF S ON FRI
THAN ON SAT. SEAS WILL PEAK IN THE 4 TO 7 FT RANGE. SE...8 TO 9
SECOND SWELL... WILL BE WEAK DURING THIS PERIOD AND WAVE HEIGHTS
WILL BE THE RESULT OF INCREASING WIND WAVE ENERGY.
LONG TERM /SUNDAY THROUGH TUESDAY/...
AS OF 3 PM THURSDAY...SOUTHERLY FLOW WILL CONTINUE AROUND WESTERN
PERIPHERY OF BERMUDA HIGH THROUGH EARLY NEXT WEEK. GRADIENT WILL
REMAIN FAIRLY TIGHT THROUGH THE WEEKEND BETWEEN LOW AND PIEDMONT
TROUGH INLAND AND HIGH PRESSURE OFF SHORE. WINDS WILL GENERALLY BE
AROUND 15 KTS NEAR SHORE WITH A SPIKE UP EACH AFTN IN SEA BREEZE.
WINDS WILL BE UP AROUND 20 IN OUTER WATERS AND UP TO 25 KTS IN
WATERS NORTH FRYING PAN. PERSISTENT SOUTHERLY FLOW WILL KEEP SEAS
UP AROUND 4 TO 6 FT THROUGH THE PERIOD. WILL MOST LIKELY END UP
WITH AN EXTENDED PERIOD OF SMALL CRAFT ADVISORY CONDITIONS FOR 6
TO 7 FT SEAS IN STRONGER SOUTHERLY FLOW ESPECIALLY IN OUTER
WATERS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR AMZ250-252-
254-256.
&&
$$
SYNOPSIS...RJD
NEAR TERM...TRA
SHORT TERM...RJD
LONG TERM...RGZ
AVIATION...DCH/MRR
AREA FORECAST DISCUSSION
NWS RALEIGH NC
142 AM EDT THU FRI 28 2013
.SYNOPSIS...
A WARM AND HUMID AIR MASS WILL HOLD OVER THE REGION FOR THE NEXT
SEVERAL DAYS... AS A LARGE LOW PRESSURE TROUGH HOLDS OVER THE
EASTERN HALF OF THE COUNTRY. PASSING UPPER LEVEL DISTURBANCES WILL
HELP PRODUCE NUMEROUS SHOWERS AND THUNDERSTORMS EACH DAY THROUGH THE
UPCOMING WEEKEND.
&&
.NEAR TERM /THROUGH FRIDAY NIGHT/...
AS OF 935 PM THURSDAY...
THE LAST CLUSTER OF ORGANIZED CONVECTION CONTINUES MOVING TO THE ESE
OVER THE SRN PIEDMONT AND SW SANDHILLS. OTHER MORE ISOLATED CELLS
ELSEWHERE HAVE BECOME STRONG BUT THEIR HIGH-REFLECTIVITY CORES HAVE
NOT QUITE REACHED THE HEIGHTS OF EARLIER STORMS. THE BOUNDARY LAYER
CONTINUES TO SLOWLY BUT STEADILY STABILIZE WITH MLCAPE DOWN TO 1500
J/KG AND GROWING CINH... AND THIS TREND SHOULD CONTINUE WITH STORMS
DISSIPATING IN THE NEXT FEW HOURS. THE LATEST COUPLE OF HRRR RUNS AS
WELL AS THE SREF AND WRF SUPPORT THIS SCENARIO WITH REMAINING STORMS
SHIFTING TO OUR EAST AND WEAKENING. DYNAMIC SUPPORT FOR ASCENT WILL
BE WANING AS THE VORTICITY AXIS SHIFTS TO OUR EAST... LEAVING BEHIND
BAGGY MID LEVEL TROUGHING OVERNIGHT WITH A LINGERING DIFFUSE TROUGH
AT THE SURFACE THROUGH THE CENTRAL CAROLINAS. WILL HOLD ONTO
EXISTING FORECAST TREND OF POPS DECREASING WEST TO EAST. EXPECT FAIR
TO PARTLY CLOUDY SKIES OVERNIGHT... ALTHOUGH THE MORE WIDESPREAD
SHOWERS/STORMS IN THE EAST ALONG WITH SLIGHTLY HIGHER DEW POINTS AND
925-850 MB MOISTURE SHOULD YIELD MORE WIDESPREAD STRATUS IN OUR
EAST. WITH THE RAIN-COOLED AIR IN SOME AREAS... CURRENT TEMPS HAVE
FALLEN TO WITHIN A FEW DEGREES OF THE DEW POINT AND HENCE ARE CLOSE
TO THE NIGHTTIME LOWS. CURRENT TEMP TRENDS PLUS STATISTICAL GUIDANCE
SUPPORT LOWS CLOSE TO THE CURRENT FORECAST OF 69-74. -GIH
FRIDAY...
SHORTWAVE ENERGY DIGGING THROUGH THE UPPER MIDWEST WILL CONTINUE TO
DEEPEN THE UPPER LEVEL TROUGH DEVELOPING OVER THE EASTERN US. A
SHARP PIEDMONT TROUGH WILL BE IN PLACE DURING THE DAY ON
FRIDAY..WITH LITTLE CHANGE IN AIRMASS EXPECTED OUTSIDE OF SLIGHTLY
LOWER DEWPOINTS IN THE WESTERN PIEDMONT. CYCLONIC FLOW
ALOFT...ALBEIT WITHOUT A NOTABLE TRIGGER IN THE MODELS...AND MODEST
INSTABILITY WILL ONCE AGAIN SUPPORT SCATTERED TO NUMEROUS
THUNDERSTORMS DURING THE AFTERNOON. WHILE ITS POSSIBLE THAT
COVERAGE MAY NOT BE AS GREAT AS THIS AFTERNOON...MID-LEVEL FLOW WILL
BE STRONGER AND DEEP LAYER SHEAR IS PROGGED TO TO EXCEED
30KT...SUGGESTING MULTICELLULAR ORGANIZATION. THE CURRENT SPC DAY
TWO OUTLOOK INCLUDES ALL OF CENTRAL NC IN A SLIGHT RISK.
REGARDING HIGH TEMPS...GUIDANCE ALMOST UNANIMOUSLY GIVES VALUES A
FEW DEGREES WARM THAN TODAY...WITH LOWER 90S ACROSS A LARGE PORTION
OF THE CWA. THIS WILL LIKELY LEAD TO HEAT INDICES NEAR 100 ACROSS
THE SANDHILLS AND SOUTHERN PIEDMONT WHERE DEWPOINTS SHOULD HOVER IN
THE LOWER 70S.
FRIDAY NIGHT...
WILL CONTINUE AT LEAST A SLIGHT CHANCE OF SHOWERS AND STORMS THROUGH
FRIDAY NIGHT AS HEIGHTS CONTINUE TO SLOWLY FALL ALOFT AND THE
AIRMASS OVER NC REMAINS HUMID. LOWS IN THE UPPER 60S AND LOWER 70S.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300 PM THURSDAY...
AN ANOMALOUSLY AMPLIFIED PATTERN WILL PREVAIL ACROSS THE CONUS
THROUGH THE WEEKEND...CHARACTERIZED BY A DEEP UPPER LEVEL RIDGE OVER
THE ROCKIES/INTERMOUNTAIN WEST AND DEEP TROUGHING EAST OF THE
MISSISSIPPI...WITH A PERSISTENT UPPER LEVEL LOW CENTERED IN VICINITY
OF THE LOWER GREAT LAKES AND OH VALLEY. ACROSS THE CAROLINAS AND
MID-ATLANTIC...EXPECT ATYPICALLY STRONG SOUTHWEST FLOW ALOFT WITH
NUMEROUS SMALL AMPLITUDE SHORTWAVES CROSSING THE REGION THROUGHOUT
THE PERIOD IN THE PRESENCE OF A SEASONABLY MOIST AIRMASS. AS A
RESULT...EXPECT ABOVE NORMAL CHANCES FOR SHOWERS AND THUNDERSTORMS
AND SLIGHTLY BELOW NORMAL HIGH TEMPS IN THE MID 80S...DEPENDING ON
CLOUD COVER AND CONVECTION. THE EXACT COVERAGE AND PERSISTENCE OF
CONVECTION WILL HIGHLY DEPEND ON THE EVOLUTION OF SMALL AMPLITUDE
DISTURBANCES IN SW FLOW ALOFT AND THE TIMING OF THESE DISTURBANCES
IN RELATION TO THE DIURNAL HEATING CYCLE. FURTHERMORE...THE DEGREE
OF DIURNAL DESTABILIZATION IS DIFFICULT TO ASCERTAIN GIVEN INCREASED
CLOUD COVER AND AN ABOVE NORMAL CHANCE FOR NOCTURNAL OR EARLY
MORNING CONVECTION...THOUGH ONE WOULD EXPECT AT LEAST SOME CLOUD
BREAKS AND AREAS OF RELATIVELY STRONGER INSOLATION DURING PEAK
HEATING. EITHER WAY...SLIGHTLY STEEPER MID-LEVEL LAPSE RATES /COOLER
TEMPS ALOFT/ IN ASSOCIATION WITH THE UNUSUALLY AMPLIFIED UPPER LEVEL
TROUGH OVER THE REGION WILL AT LEAST SOMEWHAT COMPENSATE FOR
DECREASED INSOLATION. GIVEN DEEP-LAYER (0-6 KM) SHEAR LIKELY IN THE
35-45 KT RANGE...ORGANIZED CONVECTION WILL CERTAINLY BE POSSIBLE...
INCLUDING SUPERCELLS...THOUGH THE TYPE/EXTENT OF ANY SEVERE THREAT
CANNOT BE PRECISELY IDENTIFIED AT THIS TIME. IN ADDITION TO A
POTENTIAL FOR SEVERE THUNDERSTORMS...ISOLATED FLASH FLOODING WILL
ALSO BE POSSIBLE GIVEN RECENT HEAVY RAINFALL AND ABOVE NORMAL
CHANCES FOR CONVECTION THROUGH THE WEEKEND. -VINCENT
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300 PM THURSDAY...
AN UNSEASONABLY AMPLIFIED UPPER LEVEL PATTERN WILL PERSIST ACROSS
THE CONUS THROUGH THE MIDDLE OF NEXT WEEK...CHARACTERIZED BY RIDGING
OVER THE INTERMOUNTAIN WEST...TROUGHING CENTERED IN VICINITY OF THE
MS RIVER VALLEY AND ATYPICALLY STRONG SW FLOW ALOFT OVER THE
CAROLINAS. NUMEROUS SMALL AMPLITUDE DISTURBANCES IN THE PRESENCE OF
ABOVE NORMAL MOISTURE (PWAT ~2.00") WILL RESULT IN ABOVE NORMAL
CHANCES FOR SHOWERS AND THUNDERSTORMS THROUGH EARLY/MID NEXT WEEK...
MODULATED PRIMARILY BY THE DIURNAL HEATING CYCLE...IN ADDITION TO A
CONTINUED THREAT FOR SEVERE WEATHER (GIVEN FAVORABLE DEEP-LAYER
SHEAR) AND ISOLD FLASH FLOODING. IN GENERAL EXPECT HIGHS SEVERAL
DEGREES BELOW NORMAL DUE TO INCREASED CLOUD COVER AND CHANCES FOR
CONVECTION. -VINCENT
&&
.AVIATION /06Z THURSDAY THROUGH TUESDAY/...
AS OF 145 AM FRIDAY...
UPPER S/W VORT DISTURBANCE AND ASSOCIATED CONVECTION WILL EXIT THE
SANDHILLS AND SOUTHERN COASTAL COUNTIES BY 08Z WITH SUBSIDENCE IN
THE WAKE OF THE UPPER DISTURBANCE ALLOWING FOR DRY CONDITIONS FOR
THE SECOND PART OF THE NIGHT. PATCHY SUB-VFR STRATUS AND/OR FOG
IS POSSIBLE AROUND DAYBREAK...PARTICULARLY IN AREAS THAT SAW HEAVY
RAIN THIS PAST EVENING.
ANY STRATUS/FOG SHOULD LIFT BY 15Z THIS MORNING... WITH
PREDOMINATELY VFR CONDITIONS INTO THE EARLY AFTERNOON BEFORE
ANOTHER ROUND OF SCATTERED TO NUMEROUS STORMS ARE EXPECTED
OVER CENTRAL NC.
LOOKING BEYOND FRIDAY...THE WEATHER PATTERN WILL CHANGE VERY LITTLE
THE NEXT SEVERAL DAYS. AN UNSEASONABLY STRONG LOW PRESSURE TROUGH
COMBINED WITH A WARM AND UNSTABLE AIR WILL RESULT IN SCATTER TO
NUMEROUS SHOWERS AND STORMS EACH AFTERNOON/EARLY EVENING... AND
THE POTENTIAL FOR STRATUS OR FOG EACH MORNING.
&&
.EQUIPMENT...
KRAX WSR-88D WILL BE REMAIN DOWN OR IN DEGRADED MODE THROUGH FRIDAY
MORNING. KRAX HAS BEEN IN A SEVERELY DEGRADED MODE FOR SEVERAL
DAYS... AND THE NEEDED REPAIRS WERE DEEMED TO BE CRITICAL. THE TEAM
OF TECHNICIANS WILL MAKE THESE REPAIRS AS QUICKLY AS POSSIBLE... AND
IS WORKING TO RETURN THE RADAR TO NORMAL SERVICE BY EARLY AFTERNOON
FRIDAY. WE APOLOGIZE FOR THE INCONVENIENCE. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD/BLS
SHORT TERM...VINCENT
LONG TERM...VINCENT
AVIATION...CBL
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
351 AM CDT FRI JUN 28 2013
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 350 AM CDT FRI JUN 28 2013
CHALLENGES INCLUDE CLOUD COVER/PRECIPITATION CHANCES TODAY AND
THEN TEMPERATURES THROUGH THE PERIOD. GFS/NAM/ECMWF/GEM ARE IN
GOOD AGREEMENT...BUT WILL LEAN ON LATEST RAP GUIDANCE FOR NEAR TERM
FORECAST.
FOR TODAY...STRATOCUMULUS DECK ACROSS NORTH-CENTRAL MN WILL EXPAND
SOUTH AND WEST THROUGH THE DAY GIVEN CONVECTIVE TEMPERATURES IN
THE UPPER 60S TO MID 70S. WITH A 100 KT 300 HPA JET STREAK MOVING
THROUGH NORTHWEST FLOW ALOFT AND 500 TO 1000 J/KG OF MLCAPE...
SOME OF THESE THERMAL CU MAY GIVE WAY TO SCATTERED AFTERNOON
SHOWERS AND THUNDERSTORMS. REMOVED POPS ALONG AND WEST OF THE
VALLEY THIS MORNING WITH A MOSTLY SUNNY START TO THE DAY...BUT
WILL EXPAND CHANCE POPS SOUTH AND WEST WITH INCREASING CLOUD COVER
THIS AFTERNOON. BOUNDARY LAYER IS 3 TO 6 C COLDER THAN YESTERDAY...
SO EXPECT DAYTIME HIGHS IN THE 70S. WITH 20 TO 30 KTS AT 850 HPA
TO MIX TO THE SURFACE...EXPECT ANOTHER BREEZY AFTERNOON WITH WINDS
FROM 15 TO 20 MPH AND OCCASIONAL GUSTS UP TO 30 MPH.
THERMAL CU WILL DISSIPATE AFTER SUNSET...BUT EXPECT SOME THICKER
CLOUD COVER TO TAKE ITS TIME MOVING OUT OF THE REGION OVERNIGHT.
WINDS WILL SUBSIDE WITH SURFACE HIGH PRESSURE BUILDING ACROSS THE
REGION. OVERNIGHT LOWS WILL BE IN THE 50S.
MOST OF SATURDAY WILL BE DRY...BUT DID KEEP 20 POPS REGION-WIDE
THROUGH THE DAY AS OPERATIONAL MODELS PAINT SEEMINGLY RANDOM LIGHT
QPF IN ASSOCIATION WITH A WEAK SHORT-WAVE ALOFT. SURFACE TO MID-
LEVEL FORCING IS WEAK...SO EXPECT MINIMAL ACCUMULATION WITH ANY
SHOWERS THAT DO DEVELOP. ANOTHER COOLER DAY WITH HIGHS AGAIN IN
THE 70S.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 350 AM CDT FRI JUN 28 2013
SURFACE PRESSURE RIDGE WILL SLIDE SLOWLY ACROSS THE NORTHERN
PLAINS SUNDAY AND MONDAY RESULTING IN DRY...MOSTLY SUNNY
CONDITIONS. WINDS WILL BE LIGHT AND TEMPERATURES WILL BE NEAR
SEASONAL NORMALS WITH HIGHS IN THE UPPER 70S TO LOWER 80S.
A BLEND OF THE GFS/ECMWF TO BE FOLLOWED EARLY IN THE EXTENDED THEN
TRENDING TOWARD THE GFS IN DAYS 5-7. THE UPPER PATTERN AMPLIFIES
DURING THE PERIOD WITH RIDGING OVER THE WRN CONUS AND TROF OVER THE
ERN THIRD OF THE COUNTRY. THE RIDGING OUT WEST WILL RETROGRADE
SOMEWHAT WEST ALLOWING FOR PIECES OF S/WV ENERGY TO SLIDE DOWN THE
BACK SIDE OF THE TROF BY TUE/TUE NIGHT. A FRONTAL BOUNDARY ACROSS
THE REGION WILL HELP FOCUS PRECIPITATION TUE-THU WITH WED BEING THE
MOST OPTIMAL PERIOD FOR SCATTERED SHRA/TSRA. THE BOUNDARY IS
EXPECTED TO WEAKEN BY THU. TEMPERATURES WILL BE TEMPERED WITH HIGHS
IN THE UPPER 70S TO AROUND 80 THROUGH THE WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1142 PM CDT THU JUN 27 2013
VFR CONDITIONS MOST AREAS THIS FORECAST PERIOD. EXPECT VFR CIGS TO
DEVELOP BY MID MORNING TOMORROW GRADUALLY THINNING DURING THE
AFTERNOON. NE FA MAY INITIALLY DEVELOP MVFR CIGS BECMG VFR IN THE
AFTERNOON. WILL AGAIN SEE SOME SHRA DEVELOPING.
&&
.HYDROLOGY...
ISSUED AT 930 PM CDT THU JUN 27 2013
RUNOFF CONTINUES TO MAKE ITS WAY INTO THE RED RIVER FROM AREA
TRIBUTARIES. TRENDS CONTINUE TO BE ON TARGET FROM THE MORNING
FORECAST UPDATE FOR THE RIVER POINTS. THE RED RIVER AT FARGO IS
STILL FORECAST TO CREST NEAR MAJOR FLOOD STAGE TOWARDS LATE TODAY
OR TONIGHT. OTHERWISE...RISES ARE EXPECTED TO CONTINUE OVER THE
NEXT FEW DAYS ON CENTRAL AND NORTHERN SECTIONS OF THE RED...WITH A
FEW FORECAST POINTS EXPECTED TO RISE ABOVE MINOR FLOOD STAGE.
WAHPETON REMAINS BELOW FLOOD STAGE AND IS ANTICIPATED TO CONTINUE
FALLING. HOWEVER...EXPECTED RELEASES FROM WHITE ROCK DAM MAY SLOW
THE RECESSION OF RIVER LEVELS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...ROGERS
LONG TERM...ROGERS/FRAZIER
AVIATION...VOELKER
HYDROLOGY...HOPKINS
AREA FORECAST DISCUSSION...UPDATED
NWS PENDLETON OR
1032 AM PDT WED JUN 26 2013
UPDATED AVIATION DISCUSSION
.SHORT TERM...
QUICK UPDATE TO THE FORECAST TO INCREASE CLOUDS AND CHANCES OF
PRECIPITATION FOR THIS AFTERNOON. SATELLITE IMAGERY SHOWS THE
PLUME OF PACIFIC MOISTURE STARTING TO BEND BACK TO THE NORTH AS
THE WESTERN US RIDGE BEGINS TO BUILD. A SHORT WAVE IN THIS
SOUTHWESTERLY FLOW IS CAUSING WARM ADVECTION WIDESPREAD CLOUDS TO
FORM OVER THE AREA. VISIBLE SATELLITE IMAGERY DOESN`T SHOW MUCH
HOPE OF SUNSHINE TODAY. THIS WILL LIMIT THE INSTABILITY OVER THE
AREA DESPITE THE ABUNDANT MOISTURE. THUS THERE`S NO THUNDER IN THE
FORECAST FOR NOW BUT WILL HAVE TO MONITOR THIS, ESPECIALLY OVER
CENTRAL OREGON WHERE THE SUN HAS THE BEST CHANCE OF BREAKING
THROUGH THE CLOUDS.
THE HRRR MODEL DOES SHOW SOME LIGHT SHOWERS ASSOCIATED WITH THIS
CLOUD BAND, EVEN OVER THE LOWER BASIN AREA. BUT ALL MODELS AGREE
ON A FAIRLY SHOWERY DAY OVER THE MOUNTAINS. SO I INCREASED
PRECIPITATION CHANCES OVER THE ENTIRE AREA FOR THIS AFTERNOON. RJ
&&
.AVIATION...18Z TAFS...VFR CONDITIONS WILL BE PREVALENT THROUGH
THURSDAY MORNING. LIGHT SHOWERS WILL CONTINUE ACROSS THE AREA
THROUGH AROUND 03Z THIS EVENING AFFECTING ALL TAF SITES WITH VCSH OR
-SHRA EXCEPT KYKM WHICH IS EXPECTED TO REMAIN DRY. DO NOT EXPECT ANY
THUNDERSTORMS TO DEVELOP TODAY. WHILE SHOWERS MAY CREATE BRIEF MVFR
CONDITIONS THIS AFTERNOON, CEILINGS WILL GENERALLY BE BKN-OVC AT
4000-8000 FEET THROUGH 08Z THEN BECOMING SCT-BKN ABOVE 6000 FEET
AGL. SURFACE WINDS ARE EXPECTED TO REMAIN BELOW 15 KTS FOR THE NEXT
24 HOURS. PERRY
&&
.PREV DISCUSSION... /ISSUED 317 AM PDT WED JUN 26 2013/
SHORT TERM...TODAY THROUGH THURSDAY NIGHT...ANIMATED WATER VAPOR
SATELLITE IMAGERY SHOWS A LARGE MID/UPPER LEVEL LOW PRESSURE SYSTEM
NEAR 49N/138W WITH AN UPPER LEVEL JET STREAM ON THE SOUTHERN FLANK
OF THE LOW FEEDING ASSOCIATED SUBTROPICAL MOISTURE TOWARD THE
PACIFIC NORTHWEST. WIND SPEEDS IN THE CORE OF THE JET STREAM AROUND
30000 FEET ARE 125-130 MPH WITH THE NOSE OF THE JET CURRENTLY
LOCATED SQUARELY OVER THE FORECAST AREA. SOUTHWEST FLOW ALOFT
ASSOCIATED WITH THE JET STREAM WILL STEER A DISTURBANCE NOW MAKING
LANDFALL ON THE OREGON COAST ACROSS THE REGION TODAY AND BRING
ISOLATED TO SCATTERED SHOWERS THROUGH THIS AFTERNOON TO THE
MOUNTAINS OF SE WASHINGTON AND NE OREGON, THE FOOTHILLS OF THE BLUE
MOUNTAINS, AND THE EAST SLOPES OF THE CASCADES. THE DISTURBANCE
EXITS INTO IDAHO/MONTANA THIS EVENING FOR DRY CONDITIONS AT LOWER
ELEVATIONS AND DECREASING POPS IN THE BLUE MOUNTAINS AND ALONG THE
CASCADE CRESTS TONIGHT. HEIGHT CONTOURS OF PRESSURE SURFACES IN THE
TROPOSPHERE BEGIN RISING ON THURSDAY INTO FRIDAY BY VIRTUE OF A
MID/UPPER LEVEL RIDGE OF HIGH PRESSURE THAT BUILDS OVER THE PACIFIC
NORTHWEST THROUGH THE WEEKEND WITH THE RIDGE AMPLIFICATION
CONTINUING DIRECTLY OVER THE FORECAST AREA INTO NEXT WEEK. SINKING
AIR ASSOCIATED WITH THE RIDGE WILL INITIATE A STRONG WARMING TREND
TODAY, WHICH WILL PERSIST OVER THE WEEKEND AND WELL INTO NEXT WEEK
THUS PRODUCING WELL ABOVE NORMAL HIGH TEMPERATURES EACH DAY. POLAN
LONG TERM...FRIDAY THROUGH WEDNESDAY...ALL MODELS ARE IN AGREEMENT
IN CONTINUING TO BUILD A STRONG RIDGE OF HIGH PRESSURE INTO THE
PACIFIC NORTHWEST FROM THE GREAT BASIN. CONFIDENCE OF THIS PATTERN
DEVELOPING IS INCREASING AS EACH MODEL RUN CONTINUES TO SHOW THE IT
DEVELOPING. THIS WILL RESULT IN A HEAT WAVE DURING THE EXTENDED
FORECAST PERIOD. EACH DAY WILL BECOME HOTTER THAN THE PREVIOUS FROM
FRIDAY THROUGH WEDNESDAY AS 850 MB TEMPERATURES BECOME WARMER EACH
DAY FROM THE PREVIOUS DAY AND THE CENTER OF THE HIGH PRESSURE RIDGE
BECOMING WELL ESTABLISHED OVER THE PACIFIC NORTHWEST. ON FRIDAY CAN
EXPECT HIGH TEMPERATURES TO CLIMB INTO THE LOWER TO MID 90S IN THE
LOWER ELEVATIONS...WITH UPPER 70S TO MID 80S IN THE MOUNTAINS. THE
WARMING TREND WILL CONTINUE THROUGH THE WEEKEND INTO EARLY NEXT
WEEK. BY TUESDAY 850 MB TEMPERATURES ARE INDICATING MAXIMUM SURFACE
TEMPERATURES TO BE WELL INTO THE MID 90S TO MID 100S...WITH MID 80S
TO MID 90S IN THE MOUNTAINS. THE GFS MODEL IS FORECASTING AN 850 MB
TEMPERATURE OF 31 OVER PENDLETON ON TUESDAY WHICH WHEN TRANSLATED TO
THE SURFACE IS A TEMPERATURE NEAR 110. HOWEVER...IT IS A BIT TOO
EARLY TO BELIEVE THE MODEL THAT FAR OUT IN TIME...BUT NEVERTHELESS
CONFIDENCE IS INCREASING THAT IT WILL BECOME DANGEROUSLY HOT BY
MONDAY THROUGH WEDNESDAY. THE HOT SURFACE TEMPERATURES WILL CREATE
STEEP LAPSE RATES. THERE MAY BE ENOUGH MID LEVEL MOISTURE AS WELL
SUCH THAT ISOLATED AFTERNOON AND EVENING THUNDERSTORMS COULD DEVELOP
BEGINNING FRIDAY AFTERNOON...MAINLY ALONG THE WASHINGTON CASCADES
AND THE EASTERN OREGON/SOUTHEAST WASHINGTON MOUNTAINS. 88
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 77 56 88 60 / 30 20 0 0
ALW 78 60 89 64 / 30 20 0 0
PSC 81 58 89 63 / 20 10 0 0
YKM 79 57 85 62 / 20 10 0 0
HRI 81 57 89 61 / 20 10 0 0
ELN 76 55 85 60 / 30 10 0 0
RDM 75 50 86 52 / 20 10 0 0
LGD 72 52 84 54 / 70 10 0 0
GCD 76 53 87 56 / 60 10 0 0
DLS 79 59 87 61 / 20 10 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
TODAY : GREEN
THURSDAY : GREEN
FRIDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
99/99/99
AREA FORECAST DISCUSSION
NWS PENDLETON OR
ISSUED BY NATIONAL WEATHER SERVICE SPOKANE WA
814 AM PDT WED JUN 26 2013
.SHORT TERM...
QUICK UPDATE TO THE FORECAST TO INCREASE CLOUDS AND CHANCES OF
PRECIPITATION FOR THIS AFTERNOON. SATELLITE IMAGERY SHOWS THE
PLUME OF PACIFIC MOISTURE STARTING TO BEND BACK TO THE NORTH AS
THE WESTERN US RIDGE BEGINS TO BUILD. A SHORT WAVE IN THIS
SOUTHWESTERLY FLOW IS CAUSING WARM ADVECTION WIDESPREAD CLOUDS TO
FORM OVER THE AREA. VISIBLE SATELLITE IMAGERY DOESN`T SHOW MUCH
HOPE OF SUNSHINE TODAY. THIS WILL LIMIT THE INSTABILITY OVER THE
AREA DESPITE THE ABUNDANT MOISTURE. THUS THERE`S NO THUNDER IN THE
FORECAST FOR NOW BUT WILL HAVE TO MONITOR THIS, ESPECIALLY OVER
CENTRAL OREGON WHERE THE SUN HAS THE BEST CHANCE OF BREAKING
THROUGH THE CLOUDS.
THE HRRR MODEL DOES SHOW SOME LIGHT SHOWERS ASSOCIATED WITH THIS
CLOUD BAND, EVEN OVER THE LOWER BASIN AREA. BUT ALL MODELS AGREE
ON A FAIRLY SHOWERY DAY OVER THE MOUNTAINS. SO I INCREASED
PRECIPITATION CHANCES OVER THE ENTIRE AREA FOR THIS AFTERNOON. RJ
&&
.AVIATION...12Z TAFS...VFR CONDITIONS WILL PREVAIL THROUGH WEDNESDAY
AND WEDNESDAY NIGHT AT ALL TAF SITES. THERE WILL BE ISOLATED TO
SCATTERED SHOWERS AS ANOTHER WEATHER DISTURBANCE MOVES ACROSS THE
REGION. HOWEVER...IT IS UNLIKELY THAT CONDITIONS WILL DROP TO MVFR
EXCEPT FOR VERY BRIEF TIMES AT KRDM AND/OR KBDN DUE TO LOWERED
CEILINGS AND/OR VISIBILITY IF A SHOWER OR A THUNDERSTORM MOVES
DIRECTLY OVER EITHER OF THOSE SITES. WINDS WILL REMAIN LIGHT AND
UNDER 15 KTS THROUGH TONIGHT...EXCEPT GUSTY AND ERRATIC NEAR ANY
SHOWERS OR THUNDERSTORMS THAT MAY DEVELOP. 88
&&
.PREV DISCUSSION... /ISSUED 317 AM PDT WED JUN 26 2013/
SHORT TERM...TODAY THROUGH THURSDAY NIGHT...ANIMATED WATER VAPOR
SATELLITE IMAGERY SHOWS A LARGE MID/UPPER LEVEL LOW PRESSURE SYSTEM
NEAR 49N/138W WITH AN UPPER LEVEL JET STREAM ON THE SOUTHERN FLANK
OF THE LOW FEEDING ASSOCIATED SUBTROPICAL MOISTURE TOWARD THE
PACIFIC NORTHWEST. WIND SPEEDS IN THE CORE OF THE JET STREAM AROUND
30000 FEET ARE 125-130 MPH WITH THE NOSE OF THE JET CURRENTLY
LOCATED SQUARELY OVER THE FORECAST AREA. SOUTHWEST FLOW ALOFT
ASSOCIATED WITH THE JET STREAM WILL STEER A DISTURBANCE NOW MAKING
LANDFALL ON THE OREGON COAST ACROSS THE REGION TODAY AND BRING
ISOLATED TO SCATTERED SHOWERS THROUGH THIS AFTERNOON TO THE
MOUNTAINS OF SE WASHINGTON AND NE OREGON, THE FOOTHILLS OF THE BLUE
MOUNTAINS, AND THE EAST SLOPES OF THE CASCADES. THE DISTURBANCE
EXITS INTO IDAHO/MONTANA THIS EVENING FOR DRY CONDITIONS AT LOWER
ELEVATIONS AND DECREASING POPS IN THE BLUE MOUNTAINS AND ALONG THE
CASCADE CRESTS TONIGHT. HEIGHT CONTOURS OF PRESSURE SURFACES IN THE
TROPOSPHERE BEGIN RISING ON THURSDAY INTO FRIDAY BY VIRTUE OF A
MID/UPPER LEVEL RIDGE OF HIGH PRESSURE THAT BUILDS OVER THE PACIFIC
NORTHWEST THROUGH THE WEEKEND WITH THE RIDGE AMPLIFICATION
CONTINUING DIRECTLY OVER THE FORECAST AREA INTO NEXT WEEK. SINKING
AIR ASSOCIATED WITH THE RIDGE WILL INITIATE A STRONG WARMING TREND
TODAY, WHICH WILL PERSIST OVER THE WEEKEND AND WELL INTO NEXT WEEK
THUS PRODUCING WELL ABOVE NORMAL HIGH TEMPERATURES EACH DAY. POLAN
LONG TERM...FRIDAY THROUGH WEDNESDAY...ALL MODELS ARE IN AGREEMENT
IN CONTINUING TO BUILD A STRONG RIDGE OF HIGH PRESSURE INTO THE
PACIFIC NORTHWEST FROM THE GREAT BASIN. CONFIDENCE OF THIS PATTERN
DEVELOPING IS INCREASING AS EACH MODEL RUN CONTINUES TO SHOW THE IT
DEVELOPING. THIS WILL RESULT IN A HEAT WAVE DURING THE EXTENDED
FORECAST PERIOD. EACH DAY WILL BECOME HOTTER THAN THE PREVIOUS FROM
FRIDAY THROUGH WEDNESDAY AS 850 MB TEMPERATURES BECOME WARMER EACH
DAY FROM THE PREVIOUS DAY AND THE CENTER OF THE HIGH PRESSURE RIDGE
BECOMING WELL ESTABLISHED OVER THE PACIFIC NORTHWEST. ON FRIDAY CAN
EXPECT HIGH TEMPERATURES TO CLIMB INTO THE LOWER TO MID 90S IN THE
LOWER ELEVATIONS...WITH UPPER 70S TO MID 80S IN THE MOUNTAINS. THE
WARMING TREND WILL CONTINUE THROUGH THE WEEKEND INTO EARLY NEXT
WEEK. BY TUESDAY 850 MB TEMPERATURES ARE INDICATING MAXIMUM SURFACE
TEMPERATURES TO BE WELL INTO THE MID 90S TO MID 100S...WITH MID 80S
TO MID 90S IN THE MOUNTAINS. THE GFS MODEL IS FORECASTING AN 850 MB
TEMPERATURE OF 31 OVER PENDLETON ON TUESDAY WHICH WHEN TRANSLATED TO
THE SURFACE IS A TEMPERATURE NEAR 110. HOWEVER...IT IS A BIT TOO
EARLY TO BELIEVE THE MODEL THAT FAR OUT IN TIME...BUT NEVERTHELESS
CONFIDENCE IS INCREASING THAT IT WILL BECOME DANGEROUSLY HOT BY
MONDAY THROUGH WEDNESDAY. THE HOT SURFACE TEMPERATURES WILL CREATE
STEEP LAPSE RATES. THERE MAY BE ENOUGH MID LEVEL MOISTURE AS WELL
SUCH THAT ISOLATED AFTERNOON AND EVENING THUNDERSTORMS COULD DEVELOP
BEGINNING FRIDAY AFTERNOON...MAINLY ALONG THE WASHINGTON CASCADES
AND THE EASTERN OREGON/SOUTHEAST WASHINGTON MOUNTAINS. 88
AVIATION...12Z TAFS...VFR CONDITIONS WILL PREVAIL THROUGH WEDNESDAY
AND WEDNESDAY NIGHT AT ALL TAF SITES. THERE WILL BE ISOLATED TO
SCATTERED SHOWERS AS ANOTHER WEATHER DISTURBANCE MOVES ACROSS THE
REGION. HOWEVER...IT IS UNLIKELY THAT CONDITIONS WILL DROP TO MVFR
EXCEPT FOR VERY BRIEF TIMES AT KRDM AND/OR KBDN DUE TO LOWERED
CEILINGS AND/OR VISIBILITY IF A SHOWER OR A THUNDERSTORM MOVES
DIRECTLY OVER EITHER OF THOSE SITES. WINDS WILL REMAIN LIGHT AND
UNDER 15 KTS THROUGH TONIGHT...EXCEPT GUSTY AND ERRATIC NEAR ANY
SHOWERS OR THUNDERSTORMS THAT MAY DEVELOP. 88
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 77 56 88 60 / 30 20 0 0
ALW 78 60 89 64 / 30 20 0 0
PSC 81 58 89 63 / 20 10 0 0
YKM 79 57 85 62 / 20 10 0 0
HRI 81 57 89 61 / 20 10 0 0
ELN 76 55 85 60 / 30 10 0 0
RDM 75 50 86 52 / 20 10 0 0
LGD 72 52 84 54 / 70 10 0 0
GCD 76 53 87 56 / 60 10 0 0
DLS 79 59 87 61 / 20 10 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
TODAY : GREEN
THURSDAY : GREEN
FRIDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
99/99/99
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
433 AM CDT FRI JUN 28 2013
.DISCUSSION...
A STRONG UPPER LEVEL RIDGE OF HIGH PRESSURE IS CENTERED OVER
SOUTHERN UTAH WITH THE RIDGE EASTWARD INTO EAST TEXAS. 850 MB
TEMPS CONTINUE TO WARM WITH KCRP NOW UP TO 22 C AND KLCH NOW UP TO
20 C. 700 MB TEMPS ALSO CONTINUE TO WARM AND ARE NOW UP TO 13 C.
MAX TEMPS TODAY WILL PROBABLY BE 2-3 DEGREES WARMER THAN
YESTERDAY. NAM 12 STILL HINTING THAT A SEA BREEZE CIRCULATION
WILL DEVELOP AND FEEL THIS WILL HINDER THE TEMPERATURE RISE AT
COASTAL SITES TODAY. THERE WILL BE MORE OF AN OFFSHORE FLOW ON
SATURDAY AND FEEL COASTAL SITES COULD GET PLENTY WARM AT THAT
TIME. A WEAK BOUNDARY WILL APPROACH THE EXTREME NORTH PART OF SE
TX THIS EVENING AND STALL. THE 4 KM WRF...THE RAP AND 06Z NAM 12
ARE NOW DEVELOPING SOME PCPN ALONG THE BOUNDARY. WILL SOMEWHAT
RELUCTANTLY ADD 20 POPS OVER THE EXTREME NORTH FROM 00-06Z. THE
BOUNDARY WILL CROSS SE TX ON SATURDAY WITH 500 HEIGHTS SLOWLY
DROPPING. FEEL A WARM START AND DRIER AIR ADVECTING INTO THE
REGION WILL COMPENSATE FOR THE LOWER HEIGHTS SO WILL MAINTAIN VERY
WARM TEMPS FOR SAT AFTN. A S/WV WILL MOVE SE ON THE PERIPHERY OF
THE UPPER RIDGE LATE SAT NITE INTO SUNDAY. THE TEXAS TECH WRF
SHOWS A SWATH OF PCPN DEVELOPING IN THE NW FLOW AND MOVING INTO
THE AREA BETWEEN 06-12Z SUNDAY. ADDED 20 POPS FOR THIS POTENTIAL
ON SAT NIGHT. DRIER LOW LEVEL AIR WILL ALLOW MIN TEMPS TO TREND
SLIGHTLY COOLER SUNDAY MORNING AND LOWER HEIGHTS WILL PORTEND
COOLER MAX TEMPS ON SUNDAY AFTN.
THE UPPER RIDGE RETREATS WEST ON SUNDAY AND BEYOND AS AN UPPER
LEVEL TROUGH OVER THE EASTERN U.S. RETROGRADES WEST. HEIGHTS WILL
LOWER OVER SE TX WITH A SUBTLE DECREASE IN AFTERNOON TEMPS
EXPECTED. THE AIR MASS WILL BE RATHER DRY SO AM STILL EXPECTING
MAX TEMPS TO WARM INTO THE MIDDLE 90S. MOISTURE LEVELS BEGIN TO
DEEPEN ON WEDNESDAY SO AM EXPECTING AN INCREASE IN CLOUD COVER AND
HIGHER RAIN CHANCES. THE UPPER LEVEL TROUGH WILL LINGER ACROSS
THE CENTRAL PLAINS THROUGH THE END OF NEXT WEEK. WILL CARRY RAIN
CHANCES...ADDITIONAL CLOUD COVER AND COOLER TEMPS IN RESPONSE TO
THE UPPER TROUGH. 43
&&
.MARINE...
LIGHT TO MODERATE WIND SPEEDS WILL REMAIN THROUGH THE AFTERNOON.
WINDS SHOULD THEN BECOME MODERATE AND APPROACH SCEC CRITERIA LATE
FRIDAY INTO EARLY SATURDAY AS THE THERMAL GRADIENT INCREASES ALONG
WITH THE BOUNDARY MOVING SOUTHWARDS. THE BOUNDARY SHOULD THEN STALL
OUT NEAR THE COAST ON SATURDAY THEN HAVE THE WINDS BRIEFLY SWITCH TO
THE NORTH AS A SECONDARY BOUNDARY MARCHES SOUTHWARD. THE BOUNDARY
SHOULD THEN WASH OUT AND PULL NORTHWARDS EARLY WEDNESDAY GIVING WAY
TO ONSHORE WINDS. 23
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 102 75 102 72 96 / 0 10 10 20 20
HOUSTON (IAH) 100 76 100 75 97 / 0 10 10 20 20
GALVESTON (GLS) 94 80 97 78 96 / 10 10 10 10 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...43/23
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1119 PM CDT THU JUN 27 2013
.AVIATION...
ONLY MINOR CHANGES TO FORECAST. HAVE SPED UP FROPA A COUPLE OF
HOURS BASED ON NEW MOS. ALTHOUGH THERE IS LITTLE UPPER
SUPPORT...THE LIFT ALONG THE FRONT MAY PRODUCE ISOLATED TSRA
TOMORROW AFTERNOON GIVEN THAT HIGH TEMPERATURES ARE EXPECTED TO
BE IN THE TRIPLE DIGITS. TSRA PROBABILITIES CONTINUE TO LOOK TOO
LOW TO MENTION IN TAFS AND EARLIER FROPA ALSO LOWERS POP CHANCES
IN METROPLEX.
AT WACO...FROPA FORECAST FOR ABOUT 21Z/3PM. 84
&&
.UPDATE...
THE THUNDERSTORM COMPLEX THAT EXTENDS FROM NORTHEASTERN KANSAS
SOUTHWEST THROUGH CENTRAL OKLAHOMA WEST INTO THE TEXAS PANHANDLE
CONTINUES TO MOVE SOUTHWARD THIS EVENING. A DECENT OUTFLOW
BOUNDARY IS APPARENT ON THE RADAR LOOPS THIS EVENING AHEAD OF
THIS COMPLEX. THE THUNDERSTORM COMPLEX IS EXPECTED TO WEAKEN
LATER THIS EVENING AND DISSIPATE BEFORE CROSSING THE RED RIVER
OVERNIGHT. THE 18Z TEXAS TECH WRF IS NOT REPRESENTATIVE OF WHAT
IS CURRENTLY HAPPENING. THE 00Z RUN OF THE NAM WHICH SEEMS TO BE
UNDER-DOING WHAT IS CURRENTLY OCCURRING...ALSO INDICATES THAT THE
COMPLEX SHOULD DISSIPATE BEFORE REACHING THE RED RIVER. THE HIGH
RESOLUTION RAPID REFRESH AND THE RAP INDICATE THAT THE PART OF
THE SYSTEM THAT WOULD AFFECT US ON ITS CURRENT TRACK WILL ALSO
DISSIPATE BEFORE REACHING NORTH TEXAS. SOME HIGH CLOUDS FROM THIS
ACTIVITY SPREAD INTO NORTH TEXAS LATER TONIGHT. AS FAR AS
TOMORROW IS CONCERNED. IT STILL APPEARS THAT WE WILL HAVE A
PRETTY HOT DAY WITH SOUTHWESTERLY SURFACE WINDS AHEAD OF THE WEAK
COLD FRONT. WACO MAY COME CLOSE TO THEIR RECORD HIGH FOR JUNE
28TH WHICH IS 106 DEGREES SET IN 1980. THE RECORD HIGH FOR DFW
FOR TOMORROW IS AN UNATTAINABLE /WE HOPE/ 112 DEGREES WHICH ALSO
OCCURRED IN 1980.
58
&&
.PREV DISCUSSION... /ISSUED 343 PM CDT THU JUN 27 2013/
CHANGES ARE ON THE WAY FOR NORTH AND CENTRAL TEXAS BEGINNING
TOMORROW. THROUGH THE WEEKEND...THE UPPER LEVEL RIDGE THAT HAS
BEEN DOMINATING THE AREA WILL AMPLIFY OVER THE WESTERN CONUS
WHILE AN UPPER LEVEL TROUGH DIGS DEEP OVER THE EASTERN HALF OF THE
COUNTRY. THE INFLUENCE OF THE UPPER LEVEL RIDGE WILL GREATLY BE
WEAKENED FROM THE DEEPENING TROUGH TO OUR EAST. OVERALL...THIS
WILL RESULT IN COOLER TEMPERATURES AND SLIGHT CHANCES FOR RAIN
OVER THE NEXT WEEK.
EXPECT ANOTHER MOSTLY CLEAR AND WARM NIGHT TONIGHT WITH OVERNIGHT
LOWS IN THE MID TO UPPER 70S...EXCEPT LOWER 80S IN THE DALLAS CITY
AREA. FRIDAY IS EXPECTED TO BE AN OPPRESSIVELY HOT DAY ACROSS PART
OF THE REGION DUE TO A COOL FRONT MOVING INTO THE AREA. THIS FRONT
WILL BE THE FIRST OF TWO THAT INFLUENCES NORTH AND CENTRAL TEXAS THIS
WEEKEND. SHARPLY WARMING TEMPERATURES ARE EXPECTED AHEAD OF
TOMORROWS FRONT WITH TEMPERATURES SOARING BETWEEN 101-107 AHEAD OF
THE FRONT. THE CHALLENGE IS THE SPEED AND TIMING OF THE FRONT. THE
LOCATION OF THE FRONT WILL DETERMINE WHERE THE HOTTEST
TEMPERATURES WILL OCCUR TOMORROW. MOST OF THE MODELS /INCLUDING
SHORTER TERM HI-RES MODELS/ HAVE THE FRONT AROUND THE I-20
CORRIDOR ABOUT MID AFTERNOON TOMORROW. BASED ON THIS
TIMING/LOCATION...KEPT HIGH TEMPERATURES NORTH OF I-20 IN THE MID
TO UPPER 90S...CLOSE TO 100-101 NEAR THE I-20 CORRIDOR...AND THEN
RANGING FROM 103-107 SOUTH OF THE I-20 CORRIDOR. IN
ADDITION...ALSO INTRODUCED A MENTION OF ISOLATED THUNDERSTORMS
OVER THE NORTHERN TWO-THIRDS OF THE REGION FRIDAY AFTERNOON AS
SOME MODELS INDICATE ISOLATED CONVECTION MAY DEVELOP ALONG AND
SLIGHTLY AHEAD OF THE FRONT. HOWEVER...FORECAST SOUNDINGS INDICATE
THE LOWER LEVELS OF THE ATMOSPHERE WILL BE PRETTY DRY. THIS POINTS
TO THE POTENTIAL FOR LOTS OF EVAPORATION/VIRGA FROM MID LEVEL
CLOUDS/CONVECTION AND ALSO A THREAT FOR GUSTY WINDS WITH ANY
CONVECTION THAT DOES MATERIALIZE.
BEHIND TOMORROWS COOL FRONT...DRIER AIR WILL BEGIN TO FILTER INTO
THE REGION WITH A BETTER PUSH OF DRY AIR ON SUNDAY BEHIND THE NEXT
FRONT/REINFORCING FRONT. TEMPERATURES ON SATURDAY WILL STILL BE
WARM RANGING FROM THE LOWER 90S IN THE NORTHEAST TO UPPER 90S/NEAR
100 DEGREES IN THE WEST AND SOUTHWEST. TEMPERATURES WILL FINALLY
START TO DROP SATURDAY NIGHT AND THE REMAINDER OF THE FORECAST
LOOKS TO BE GENERALLY BELOW NORMAL. THE LATEST SET OF MODEL RUNS
INDICATE THAT THE AIR BEHIND SUNDAY/S FRONT WILL BE DRIER THAN
PREVIOUS MODEL RUNS...WITH DEWPOINTS IN THE 50S AND LOWER 60S
THROUGH AT LEAST MID WEEK. THIS WILL RESULT IN LOWER OVERNIGHT
LOWS AND ALSO MORE PLEASANT DAYTIME HIGHS FOR THIS TIME OF YEAR. IN
SUMMARY...OVERNIGHT LOWS WILL MOSTLY BE IN THE 60S AND
OCCASIONALLY LOWER 70S...DAYTIME HIGHS WILL BE IN THE MID 80S TO
LOWER 90S. IT IS ALSO GOING TO FEEL MUCH DRIER WITH LOWER HUMIDITY
VALUES THANKS TO THE LOWER DEWPOINT TEMPERATURES.
WHILE THERE ARE SOME CHANCES FOR RAIN THROUGH THE FORECAST
PERIOD...THE BEST CHANCES FOR RAIN MAY ACTUALLY COME NEAR THE END
OF THE FORECAST...NEAR THE JULY 4TH HOLIDAY. HAVE TAPERED BACK THE
POPS FOR SATURDAY AS IT LOOKS LIKE THE RIDGE WILL HOLD STRONG OVER
OUR WESTERN COUNTIES. THERE ARE STILL SLIGHT CHANCES FOR RAIN
OVER THE REGION ON SUNDAY AS THE NEXT FRONT ARRIVES. WITH THE
DRIER AIR EXPECTED BEHIND SUNDAY/S FRONT...RAIN CHANCES EARLY NEXT
WEEK ARE SLIM BUT NOT COMPLETELY ZERO. WE WILL BE UNDER THE
INFLUENCE OF NORTHERLY FLOW ALOFT BETWEEN THE UPPER TROUGH TO OUR
EAST AND THE RIDGE TO OUR WEST. HOWEVER...IT/S DIFFICULT TO PIN
POINT EXACTLY WHEN AND WHERE ISOLATED CONVECTION WILL OCCUR THIS
PATTERN AND KEPT GHOST 10 POPS IN THE FORECAST. WE COULD HAVE
ISOLATED AFTERNOON CONVECTION NEAR OR IN OUR FAR EASTERN
ZONES...CLOSER TO THE UPPER LEVEL TROUGH. BY THE MIDDLE TO END OF
NEXT WEEK...THE UPPER LEVEL TROUGH TO OUR EAST WILL EXPAND FARTHER
WEST AND WE COULD SEE SOME DISTURBANCES CROSSING THE REGION.
INTRODUCED 20 POPS FOR NOW ON WEDNESDAY AND THURSDAY OF NEXT WEEK.
82/JLD
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 78 102 76 98 72 / 0 10 5 10 10
WACO, TX 76 104 75 99 71 / 0 10 10 10 10
PARIS, TX 74 97 71 92 66 / 5 10 5 10 10
DENTON, TX 76 99 73 97 69 / 5 10 5 10 10
MCKINNEY, TX 75 99 72 96 69 / 0 10 5 10 10
DALLAS, TX 81 102 77 98 74 / 0 10 5 10 10
TERRELL, TX 76 101 74 96 70 / 0 10 5 10 10
CORSICANA, TX 76 105 75 98 71 / 0 10 10 10 10
TEMPLE, TX 74 103 75 99 71 / 0 10 10 10 10
MINERAL WELLS, TX 77 103 73 98 69 / 0 10 5 10 10
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1116 AM EDT FRI JUN 28 2013
.SYNOPSIS...
A BROAD AREA OF LOW PRESSURE WILL REMAIN OVER THE NORTHEAST AND
IMPACT THE REGION THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK.
THE BERMUDA HIGH WILL STRENGTHEN AND BUILD BACK TOWARD THE
EASTERN SEABOARD BY THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CAPES ALREADY RUNNING 1500-2000 J/KG ACROSS MOST OF THE TRI-STATE
AT 14Z PER LAPS ANALYSIS. HOWEVER CORE OF LOW LEVEL JET IS TO THE
EAST...AND THE REGION IS IN THE RIGHT FRONT QUADRANT OF AN 80+ KT
250 HPA JET PER 12Z RAOBS. SO WHILE HAVE THE CAPE...NOT THE MUCH
THE WAY IN FORCING TO PLAY WITH...OUTSIDE OF RESIDUAL BOUNDARIES
FROM YESTERDAY/S CONVECTION AND LINGERING TROUGH OVER THE LOWER
HUDSON VALLEY/NE NJ. LATEST HRRR AND RUC PAINT A PICTURE OF ISOLD-
SCT CONVECTION FOR REMAINDER OF THE DAY. HAVE LOWERED POPS
SLIGHTLY LATE THIS AFTERNOON OVER ZONES TO BELOW 55 PERCENT TO ACCOMMODATE
THIS.
FOR NOW TEMPERATURE FORECAST FOR SLIGHTLY ABOVE NORMAL HIGHS
APPEARS ON TRACK.
THERE IS A HIGH RISK OF RIP CURRENTS AT ALL ATLANTIC OCEAN BEACHES
THROUGH THIS EVENING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
CONVECTION SHOULD DIE DOWN DURING THE EVENING AS IT MOVES EAST
ACROSS LONG ISLAND AND SOUTHERN CT...BUT THEN ANOTHER ROUND OF
SHOWERS AND POSSIBLE TSTMS IS LIKELY LATE TONIGHT INTO SAT
MORNING...ESPECIALLY EAST ACROSS LONG ISLAND AND SOUTHERN CT...AS
A WEAK MID LEVEL IMPULSE MOVES UP THE COAST. LAST TWO RUNS OF THE
ECMWF HAVE BEEN MOST AGGRESSIVE WITH THIS FEATURE...HAVE ACCEPTED
THIS IDEA BUT TEMPERED WITH THE WEAKER GFS SOLUTION.
TEMPERATURES SHOULD CONTINUE TO RUN SLIGHTLY ABOVE SEASONAL NORMS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
THE UNSETTLED WEATHER PATTERN CONTINUES THIS WEEKEND INTO THE
BEGINNING OF NEXT WEEK WITH THE ONGOING THREAT FOR SHOWERS AND
THUNDERSTORMS AS THE REGION SITS BETWEEN A STRONG BERMUDA HIGH/UPPER
LEVEL RIDGE TO THE EAST AND A DEEP UPPER LEVEL TROUGH OVER THE GREAT
LAKES REGION. THIS SYNOPTIC SET UP PROVIDES A CONTINUAL SOUTHERLY
FLOW...USHERING IN WARM...VERY MOIST AIR. THE LATEST 00Z MODEL RUNS
HAVE GENERALLY GOOD AGREEMENT ON THE PLACEMENT OF THESE
FEATURES...WITH ONLY SLIGHT DIVERGENCE TOWARDS THE END OF THE
FORECAST PERIOD.
SURFACE LOW HOVERS OVER SOUTHEASTERN CANADA SAT NIGHT...WITH A
STATIONARY FRONT POSITIONED THROUGH THE TRI STATE AREA. 00Z MODELS
HINT OF A BRIEF PERIOD OF DRYING OUT...WITH PW VALUES ONLY AROUND
1.2/1.3 INCHES FOR SAT NIGHT. MADE MENTION OF CHANCE OF
SHOWERS/THUNDERSTORMS SAT NIGHT AS A SHORTWAVE PIVOTS AROUND THE
EASTERN SIDE OF THE UPPER LEVEL TROUGH. BEST COMBO OF
INSTABILITY/SHEAR LOOKS TO BE FARTHER INLAND NORTH AND WEST OF THE
CITY...BUT A STRONGER TSTM IS POSSIBLE WITH INSTABILITY VALUES
BETWEEN 1000-1500 J/KG AND 0-6KM SHEAR BETWEEN 30 AND 35 KTS. AS THE
NEXT SURFACE LOW TRACKS ALONG THE FRONT TO THE NORTHEAST SUNDAY...PW
VALUES INCREASE GREATLY OVER THE AREA...WITH VALUES AROUND 2.0
INCHES EXPECTED BY THE AFTERNOON ALONG THE CONTINUAL SOUTHERLY FLOW. SHEAR
AND INSTABILITY VALUES REMAIN MARGINAL...WITH THE THINKING THAT
HEAVY RAIN WILL BE THE MAIN THREAT WITH ANY SHOWERS AND
THUNDERSTORMS THAT FORM SUNDAY.
SHOWERS AND THUNDERSTORMS REMAIN LIKELY IN THE FORECAST FOR THE
FIRST PART OF THE WEEK WITH THE STATIONARY FRONT HUGGING THE
NORTHEAST AND MULTIPLE SHORTWAVES SQUEEZING BETWEEN THE UPPER LEVEL
TROUGH TO THE WEST AND THE RIDGE TO THE EAST. BY TUESDAY...THE
BERMUDA HIGH/UPPER LEVEL RIDGE NUDGES INTO THE
NORTHEAST...DIMINISHING THE THREAT FOR WIDESPREAD PRECIPITATION. THE
THREAT FOR THUNDERSTORMS BECOMES MORE DIURNAL AT THIS POINT WITH THE
PASSING SHORTWAVES COMBINED WITH DAY TIME HEATING BECOMING THE MAIN
TRIGGER RATHER THAN THE FRONTAL BOUNDARY. HAVE INCLUDED CHANCE POPS TO
ACCOUNT FOR THIS THROUGH THE END OF THE WEEK...WITH SOME DRYING
FINALLY EXPECTED BY FRIDAY AS THE RIDGE AND SURFACE HIGH TAKE MORE
CONTROL OF THE NORTHEAST AS THE UPPER LEVEL TROUGH FINALLY WEAKENS
AND PROGRESSES EAST.
TEMPS NEAR NORMAL FOR THE PERIOD...WITH HIGHS GENERALLY IN THE 80S
AND LOWS IN THE UPPER 60S TO LOWER 70S.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
LOW PRESSURE CURRENTLY MOVING AWAY FROM THE REGION TO THE NORTH. A
FRONTAL BOUNDARY STALLS OVER THE AREA TODAY.
BRIEF SHRA POSSIBLE ACROSS CITY AND INTERIOR TERMINALS LATE THIS
MORNING. MINIMAL IMPACT TO OPERATIONS EXPECTED.
SCT SHRA AND TSTMS POSSIBLE LATER WITH BETTER OVERALL CHANCES IN THE
LATE AFTERNOON INTO EVENING AND HAVE SHOWN THAT VIA TEMPO GROUP
EVERYWHERE EXCEPT ISP/GON.
GENERALLY VFR...EXCEPT FOR EASTERN TERMINALS...WHICH MAY SEE MVFR
CIGS THROUGHOUT THE DAY. MODERATE CONFIDENCE IN GUSTS DEVELOPING BY
16-17Z.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KEWR FCSTER COMMENTS: LOW-MODERATE CONFIDENCE IN COVERAGE OF TSTMS.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KJFK FCSTER COMMENTS: LOW-MODERATE CONFIDENCE IN COVERAGE OF TSTMS.
OCCASIONAL MVFR CEILINGS POSSIBLE THROUGH 19-20Z.
KLGA FCSTER COMMENTS: LOW-MODERATE CONFIDENCE IN COVERAGE OF TSTMS.
OCCASIONAL MVFR CEILINGS POSSIBLE THROUGH 18Z.
KTEB FCSTER COMMENTS: LOW-MODERATE CONFIDENCE IN COVERAGE OF TSTMS.
KHPN FCSTER COMMENTS: LOW-MODERATE CONFIDENCE IN COVERAGE OF TSTMS.
KISP FCSTER COMMENTS: OCCASIONAL MVFR CEILINGS POSSIBLE THROUGH 18Z.
.OUTLOOK FOR 15Z SAT THROUGH TUESDAY...
.SAT-TUE...SUB VFR POSSIBLE AT TIMES WITH PERIODS OF SHOWERS AND
TSTMS.
&&
.MARINE...
SCA REMAINS UP ON THE OCEAN WATERS INTO SATURDAY WITH SEAS AROUND
5 FT...AND POSSIBLE GUSTS UP TO 25 KTS.
SCA CONDITIONS EXPECTED ON THE OCEAN WATERS THROUGH THE WEEKEND WITH
SEAS BETWEEN 7 AND 9 FT. WIND GUSTS MAY TOUCH 25 KTS AS WELL DURING
THIS TIME. SEAS REMAIN ELEVATED DURING THE COMING WEEK WITH A
PERSISTENT SOUTHERLY FLOW CONTINUALLY BUILDING UP THE SEAS. WINDS
HOWEVER EXPECTED TO REMAIN BELOW SCA CRITERIA...SO ALL WATERS OTHER
THAN THE OCEAN SHOULD REMAIN SUB SCA.
WILL CONTINUE TO UNDERCUT WAVE WATCH III SEAS BY A FOOT OR SO.
&&
.HYDROLOGY...
CONFIDENCE IN FLASH FLOOD WATCH IS DECREASING. IF CURRENT
CONVECTIVE TRENDS HOLD...COULD CANCEL EARLY THIS AFTERNOON.
WITH SOME UNCERTAINTY ON THE EVOLUTION OF CONVECTION LATER
TODAY...HAVE EXTENDED FLASH FLOOD WATCH INTO THIS EVENING FROM NYC
METRO NORTH/WEST AND FOR SOUTHWEST CT. CANCELED WATCH FOR EASTERN
LONG ISLAND AND SW CT WHERE INSTABILITY AND POTENTIAL FOR HEAVY
RAIN WILL BE MITIGATED BY A MORE STABLE ONSHORE FLOW.
SHOWERS AND THUNDERSTORMS SUNDAY INTO MONDAY MAY PRODUCE HEAVY
RAINFALL...WITH LOCALIZED FLOODING...ESPECIALLY OVER URBAN AND POOR
DRAINAGE AREAS. STILL TOO EARLY AT THIS TIME TO DETERMINE RAINFALL
TOTALS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND STREAMS...INCLUDING
OBSERVED AND FORECAST RIVER STAGES...PLEASE VISIT THE ADVANCED
HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...FLASH FLOOD WATCH UNTIL 9 PM EDT THIS EVENING FOR CTZ005-006-
009-010.
NY...FLASH FLOOD WATCH UNTIL 9 PM EDT THIS EVENING FOR NYZ067>075-
176>179.
NJ...FLASH FLOOD WATCH UNTIL 9 PM EDT THIS EVENING FOR NJZ002-004-
006-103>108.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR ANZ350-353-
355.
&&
$$
SYNOPSIS...MALOIT/GOODMAN/SEARS
NEAR TERM...MALOIT/GOODMAN
SHORT TERM...GOODMAN
LONG TERM...SEARS
AVIATION...BC/DH
MARINE...MALOIT/GOODMAN/SEARS
HYDROLOGY...MALOIT/GOODMAN/SEARS
AREA FORECAST DISCUSSION
NWS TAUNTON MA
919 AM EDT FRI JUN 28 2013
.SYNOPSIS...
WARM AND MUGGY CONDITIONS WILL CONTINUE WITH HIT AND MISS SHOWERS
AND THUNDERSTORMS INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
*** FLASH FLOOD WATCH IS IN EFFECT THROUGH THIS AFTERNOON. ***
9 AM UPDATE...MOST OF THE SHOWERS ARE MOVING OFF THE EAST COAST OF
MASSACHUSETTS AT THIS TIME. THERE REMAIN SHOWERS STRETCHED FROM
CAPE ANN TO THE MIDDLE OF CAPE COD. THESE SHOWERS WILL CONTINUE TO
MOVE EASTWARD THIS MORNING. THERE IS ALSO A THIN LINE OF SHOWERS
STRETCHED THROUGH THE CONNECTICUT VALLEY RIGHT NOW THAT WILL
SLOWLY MAKE ITS WAY EAST. APPEARS THAT THE WARM FRONT RUNS FROM
JUST NORTH OF ALBANY SOUTHEAST TO JUST SOUTH OF WORCESTER BACK TO
THE NORTHEAST TO ABOUT LAWRENCE. EXPECT THIS FRONT TO CONTINUE TO
MOVE NORTHWARD AS LOW PRESSURE IN EASTERN NEW YORK STRENGTHENS.
WIND GUSTS MAY INCREASE ACROSS THE WEST AS PRESSURE GRADIENT
TIGHTENS...UP TO 25 KTS. ON THE CAPE AND ISLANDS...WINDS WILL BE
AIDED BY A LOW LEVEL JET. MANY LOCATIONS IN THIS REGION ARE
ALREADY GUSTING TO 25 KTS.
.PREVIOUS DISCUSSION...
MODELS ARE SHOWING SOME DRYING IN THE MID-LEVELS BY LATE THIS
MORNING INTO THE EARLY AFTERNOON HOURS. MAIN QUESTION IS THE
POTENTIAL FOR STRONG THUNDERSTORMS LATER TODAY. MODELS ARE
INDICATING THAT CLOUD COVER WILL BREAK LATER ALLOWING FOR SOME
DIURNAL HEATING AND EVENTUALLY SOME THUNDERSTORMS. THE HI-RES WRF
AS WELL AS THE HRRR AND OTHER MESOSCALE MODELS ARE ALSO INDICATING
THIS FEATURE. IF THIS DOES PLAY OUT BELIEVE THE REGION THAT HAS
THE BEST POTENTIAL WILL BE ACROSS THE WORCESTER HILLS AND WEST.
THIS REGION SHOWS THE BETTER INSTABILITY...UP TO 2000 J/KG
COMBINED WITH BULK SHEAR VALUES AROUND 30KTS AND LAPSE RATES OF 6
C/KM. ALSO HAVE UPPER LEVEL SUPPORT AS THE EXIT REGION OF THE JET
MOVES OVER SOUTHERN NEW ENGLAND. IF THUNDERSTORMS DO DEVELOP
BELIEVE THAT GUSTY WINDS...HAIL AND HEAVY DOWNPOURS WILL BE THE
MAIN THREATS.
TEMPERATURES WILL BE TRICKY AGAIN TODAY. WARM FRONT WILL LIFT
NORTHWARD ALLOWING FOR WARM AND MOIST AIR INTO THE REGION. HOWEVER
FOG AND CLOUDS WILL LIMIT TRUE DIABATIC HEATING. RIGHT NOW EXPECT
TEMPS TO BE IN THE MID TO UPPER 70S. IF THE SUN DOES PEAK OUT THEN
TEMPS MAY WARM INTO THE LOW 80S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
ANY ONGOING CONVECTION SHOULD DWINDLE DOWN DURING THE EVENING
HOURS AS DIURNAL HEATING IS LOST. STILL LEFT SCATTERED SHOWERS IN
THE FORECAST. OTHERWISE MAIN CONCERN WILL BE FOG FOR THE OVERNIGHT
HOURS AS VERY HUMID AIRMASS IS STILL IN PLACE. MODELS ARE
INDICATING ANOTHER SURGE OF PRECIP TO PUSH ACROSS THE CAPE AND
ISLANDS AFTER MIDNIGHT FROM THE LLJ.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
OVERVIEW...NOT MUCH CHANGE IN THE OVERALL SYNOPTIC PATTERN WITH
THE 28/00Z GUIDANCE. STILL DO NOT HAVE MUCH CONFIDENCE IN THE
MESOSCALE DETAILS EVIDENT IN ANY PARTICULAR MODEL. WITH ABOVE
AVERAGE AGREEMENT WITH RESPECT TO THE OVERALL SYNOPTIC
EVOLUTION...DECIDED TO USE A CONSENSUS BLEND TO TREND THE EXISTING
FORECAST.
THIS SOLUTION WILL FEATURE STRONG RIDGES DEVELOPING OVER THE
WESTERN USA AS WELL AS THE WESTERN ATLANTIC. A SHORTWAVE MOVING
OVER THE GREAT LAKES INTO THE MISSISSIPPI VALLEY AND FORMS AN
ANOMALOUSLY STRONG CUTOFF LOW OVER THAT AREA. THIS UPPER LOW
EVENTUALLY EJECTS INTO THE /CANADIAN/ WESTERLIES DURING THE MIDDLE
OF NEXT WEEK.
THE DAILIES...
SATURDAY... ANOTHER SHORTWAVE ROTATES AROUND A GREAT LAKES UPPER
LOW AND CROSSES EASTERN NY/NEW ENGLAND. A SUPPORTING UPPER JET HAS
ITS RIGHT ENTRANCE REGION OVER NEW ENGLAND. A COLD FRONT STALLS
OVER OR NEAR THE REGION AND PROVIDES A FOCUS FOR LOW LEVEL
CONVERGENCE. PLENTY OF MOISTURE AVAILABLE WITH PRECIPITABLE WATER
VALUES BETWEEN 1.5 AND 2.0 INCHES...HIGHEST SOUTHEAST. WE WILL
FEATURE HIGHER POPS. WE WILL ALSO MENTION LOCALLY HEAVY DOWNPOURS
DUE TO THE HIGH MOISTURE CONTENT.
SUNDAY THROUGH THURSDAY...NOT MUCH CHANGE IN THE UPPER PATTERN
WITH CLOSED LOW TO THE WEST AND UPPER RIDGE TO THE EAST...AND A
MOIST SOUTH FLOW CONTINUING TO SUPPLY HIGH MOISTURE CONTENT AIR.
WE WILL CONTINUE TO FEATURE AT LEAST A CHANCE OF SHOWERS AND
THUNDERSTORMS IN THE FORECAST.
&&
.AVIATION /13Z FRIDAY THROUGH TUESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
TODAY...MODERATE CONFIDENCE. IFR/LIFR CONDITIONS EARLY...
IMPROVING TO MVFR/IFR EAST AND MVFR/PATCHY VFR WEST. OVERALL
IMPROVEMENTS BY LATE MORNING WEST TO EAST. HOWEVER SHOWERS AND
THUNDERSTORMS WILL REDEVELOP DURING THE LATE MORNING AND
AFTERNOON HOURS. THEREFORE MVFR OUT WEST IN ANY HEAVY
THUNDERSTORM.
TONIGHT...VFR/MVFR WILL SLOWLY DROP TO MVFR/IFR ACROSS THE REGION
IS LOW CLOUDS AND FOG. BEST REGION FOR LOWEST CONDITIONS WILL BE
ALONG THE SOUTH COAST.
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. CONFIDENT IN OVERALL
TRENDS HOWEVER LOW CONFIDENCE IN TIMING...PARTICULARLY WITH
CONVECTION.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF. CONFIDENT IN OVERALL
TRENDS HOWEVER LOW CONFIDENCE IN TIMING...PARTICULARLY WITH
CONVECTION.
OUTLOOK...SATURDAY THROUGH TUESDAY...
MODERATE CONFIDENCE.
PLENTY OF SHOWERS/TSTMS THIS WEEKEND WITH PERIODS OF MVFR
CIGS/VSBYS IN SHOWERS...SOME OF THEM QUITE HEAVY. THE VERY HUMID
AIRMASS WILL ALSO PRODUCE AREAS OF FOG AT NIGHT AND EARLY MORNING
WITH IFR CIGS/VSBYS IN ANY SUCH FOG. POTENTIAL FOR VSBYS NEAR 1/4
MILE AT TIMES.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT-TERM THROUGH FRIDAY...HIGH CONFIDENCE.
SHORT-TERM THROUGH FRIDAY NIGHT...HIGH CONFIDENCE.
SCA STILL CONTINUES ACROSS THE WATERS. CONTINUED TO UNDERCUT WNA
WAVE GUIDANCE BY ABOUT 10 PERCENT TO ACCOUNT FOR ITS SOUTHERLY
BIAS. OTHERWISE SHOWERS AND THUNDERSTORMS WILL CONTINUE TO
IMPACT THE WATERS TODAY AND INTO TONIGHT. MAIN THREATS WILL BE
LIGHTNING AND HEAVY DOWNPOURS IMPACTING VISIBILITIES.
OUTLOOK...SATURDAY THROUGH TUESDAY...
PERIODS OF SHOWERS/TSTMS/FOG EXPECTED WITH VERY HUMID AIR
CONTINUING. THERE WILL BE POOR VSBYS AT TIMES...AND 1/4 MILE
VSBYS IN FOG POSSIBLE EARLY EACH MORNING. SOUTH TO SOUTHWEST WINDS
THROUGH THE PERIOD. WIND GUSTS MAY APPROACH 25 KNOTS AT TIMES
SATURDAY...BUT BE PRIMARILY 20 KNOTS OR LESS. THE STEADY WIND
DIRECTION WILL HELP BUILD SEAS WITH WAVE HEIGHTS OF 5 TO 10 FEET
EXPECTED ACROSS THE OUTER COASTAL WATERS AND EXPOSED PORTIONS OF
THE SOUTHERN SOUNDS SUCH AS RI SOUND AND POSSIBLY BLOCK ISLAND
SOUND. A SMALL CRAFT ADVISORY WILL BE NEEDED FOR THESE ROUGH SEAS
THROUGH MIDWEEK...ESPECIALLY ACROSS THE OUTER COASTAL WATERS.
&&
.HYDROLOGY...
FLASH FLOOD WATCH CONTINUES THROUGH TODAY. RADAR ESTIMATED
RAINFALL RATES UP TO 6 IN PER HOUR WITHIN SOME OF THE STRONGER
THUNDERSTORMS LAST NIGHT. FORTUNATELY THESE THUNDERSTORMS REMAINED
PROGRESSIVE AND DID NOT LINGER OVER ANY ONE LOCATION FOR VERY
LONG. THESE RAINFALL RATES DO INDICATE THE POTENTIAL FOR HEAVY
RAINFALL WITHIN THIS SOUPY AIRMASS.
WILL NEED TO ESPECIALLY WATCH REGIONS OF HIGHER TERRAIN WHERE
UPSLOPE COULD ENHANCE THE RAINFALL AS WELL AS URBANIZED AREAS...
WHERE CONVECTIVE HEAVY RAIN MAY LEAD TO URBAN FLASH FLOODING.
&&
.CLIMATE...
WITH THE POTENTIAL FOR HEAVY RAIN TONIGHT INTO FRIDAY WE WILL BE
ADDING TO THE ALREADY HIGH MONTHLY TOTALS FOR RAIN. BELOW PLEASE
FIND THE TOP 10 WETTEST JUNE RAINFALL TOTALS FOR EACH OF OUR FOUR
CLIMATE SITES...THESE INCLUDE RAINFALL TOTALS FOR JUNE 2013 ENDING
AT 1 AM THE MORNING OF JUNE 28.
BOSTON...
1. 13.20 INCHES IN 1982
2. 11.58 INCHES IN 1998
3. 10.09 INCHES IN 2006
4. 9.87 INCHES IN 2013
5. 9.13 INCHES IN 1931
6. 8.63 INCHES IN 1959
7. 8.05 INCHES IN 1922
8. 7.79 INCHES IN 1881
9. 7.74 INCHES IN 1986
10. 7.25 INCHES IN 1875
HARTFORD...
1. 13.60 INCHES IN 1982
2. 10.62 INCHES IN 2013
3. 9.66 INCHES IN 1972
4. 9.16 INCHES IN 2006
5. 8.08 INCHES IN 1937
6. 8.00 INCHES IN 1920
7. 7.79 INCHES IN 1948
8. 7.18 INCHES IN 1998
9. 6.92 INCHES IN 1922
10. 6.79 INCHES IN 1986
PROVIDENCE...
1. 11.08 INCHES IN 1982
2. 9.61 INCHES IN 1998
3. 9.39 INCHES IN 2013
4. 9.24 INCHES IN 2006
5. 7.21 INCHES IN 1938
6. 6.83 INCHES IN 1978
7. 6.80 INCHES IN 1920
8. 6.72 INCHES IN 2001
9. 6.58 INCHES IN 1922
10. 5.84 INCHES IN 1989
WORCESTER...
1. 12.17 INCHES IN 1982
2. 9.68 INCHES IN 1998
3. 9.55 INCHES IN 2013
4. 9.25 INCHES IN 1972
5. 8.31 INCHES IN 1922
6. 7.78 INCHES IN 1968
7. 7.44 INCHES IN 1903
8. 7.39 INCHES IN 1938
9. 7.21 INCHES IN 1986
10. 6.98 INCHES IN 1973 & 1935
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR CTZ002>004.
MA...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR MAZ002>021-
026.
NH...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR NHZ011-012-
015.
RI...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR RIZ001>007.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
ANZ231>234.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR ANZ235-237-
250-254>256.
&&
$$
SYNOPSIS...BELK/DUNTEN
NEAR TERM...BELK/DUNTEN/RLG
SHORT TERM...DUNTEN
LONG TERM...BELK
AVIATION...BELK/DUNTEN
MARINE...BELK/DUNTEN
HYDROLOGY...STAFF
CLIMATE...STAFF
AREA FORECAST DISCUSSION
NWS TAUNTON MA
745 AM EDT FRI JUN 28 2013
.SYNOPSIS...
WARM AND MUGGY CONDITIONS WILL CONTINUE WITH HIT AND MISS SHOWERS
AND THUNDERSTORMS INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
730 AM UPDATE...OVERALL FORECAST TREND REMAINS ON TRACK. HAVE
UPDATED TO ACCOUNT FOR CURRENT SITUATION. APPEARS WARM FRONT IS
DRAPED FROM JUST NORTH OF PROVINCETOWN...TO JUST SOUTH OF
WORCESTER...THEN NORTHWEST INTO SOUTHERN VERMONT. EXPECT THIS
FRONT TO CONTINUE NORTHWARD AS A LOW PRESSURE STRENGTHENS. WIND
GUSTS MAY INCREASE ACROSS THE WEST AS PRESSURE GRADIENT
TIGHTENS...UP TO 25 KTS.
TODAY...
*** FLASH FLOOD WATCH IS IN EFFECT THROUGH THIS AFTERNOON. ***
LOW PRESSURE SYSTEM WILL SLIDE NORTHWARD BY FRIDAY. THIS WILL
PUSH THE WARM FRONT/BOUNDARY NORTHWARD INTO NH ALLOWING FOR GOOD
SOUTHERLY FLOW ACROSS THE REGION. SCATTERED SHOWERS WILL CONTINUE
ESP ACROSS THE NORTHWEST PORTION OF THE REGION THIS MORNING. A FEW
EMBEDDED THUNDERSTORMS MAY OCCUR AS WELL. OTHERWISE BELIEVE
OVERALL AREAL COVERAGE WILL BE DISSIPATING. LOW LEVEL JET WILL
STILL BE ANCHORED ACROSS THE CAPE/EASTERN WATERS THROUGH THE DAY
WHICH COULD MAKE THINGS A TAD BREEZY ACROSS THE CAPE AND ISLANDS.
MODELS ARE SHOWING SOME DRYING IN THE MID-LEVELS BY LATE THIS
MORNING INTO THE EARLY AFTERNOON HOURS. MAIN QUESTION IS THE
POTENTIAL FOR STRONG THUNDERSTORMS LATER TODAY. MODELS ARE
INDICATING THAT CLOUD COVER WILL BREAK LATER ALLOWING FOR SOME
DIURNAL HEATING AND EVENTUALLY SOME THUNDERSTORMS. THE HI-RES WRF
AS WELL AS THE HRRR AND OTHER MESOSCALE MODELS ARE ALSO INDICATING
THIS FEATURE. IF THIS DOES PLAY OUT BELIEVE THE REGION THAT HAS
THE BEST POTENTIAL WILL BE ACROSS THE WORCESTER HILLS AND WEST.
THIS REGION SHOWS THE BETTER INSTABILITY...UP TO 2000 J/KG
COMBINED WITH BULK SHEAR VALUES AROUND 30KTS AND LAPSE RATES OF 6
C/KM. ALSO HAVE UPPER LEVEL SUPPORT AS THE EXIT REGION OF THE JET
MOVES OVER SOUTHERN NEW ENGLAND. IF THUNDERSTORMS DO DEVELOP
BELIEVE THAT GUSTY WINDS...HAIL AND HEAVY DOWNPOURS WILL BE THE
MAIN THREATS. SPC HAS OUTLOOKED MOST OF THE REGION WITHIN THEIR
DAY 1 OUTLOOK. WE HAVE ALSO BEEN PLACED IN A 2 PERCENT TORNADO
PROBABILITY. BELIEVE THE POTENTIAL IS LOW ESP SINCE SURFACE WINDS
WILL BE MORE OUT OF THE SOUTH RATHER THAN THE WSW ALTHOUGH IT IS
SOMETHING FOR THE DAY SHIFT TO EVALUATE.
TEMPERATURES WILL BE TRICKY AGAIN TODAY. WARM FRONT WILL LIFT
NORTHWARD ALLOWING FOR WARM AND MOIST AIR INTO THE REGION. HOWEVER
FOG AND CLOUDS WILL LIMIT TRUE DIABATIC HEATING. RIGHT NOW EXPECT
TEMPS TO BE IN THE MID TO UPPER 70S. IF THE SUN DOES PEAK OUT THEN
TEMPS MAY WARM INTO THE LOW 80S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
ANY ONGOING CONVECTION SHOULD DWINDLE DOWN DURING THE EVENING
HOURS AS DIURNAL HEATING IS LOST. STILL LEFT SCATTERED SHOWERS
IN THE FORECAST. OTHERWISE MAIN CONCERN WILL BE FOG FOR THE
OVERNIGHT HOURS AS VERY HUMID AIRMASS IS STILL IN PLACE. MODELS
ARE INDICATING ANOTHER SURGE OF PRECIP TO PUSH ACROSS THE CAPE AND
ISLANDS AFTER MIDNIGHT FROM THE LLJ.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
OVERVIEW...NOT MUCH CHANGE IN THE OVERALL SYNOPTIC PATTERN WITH
THE 28/00Z GUIDANCE. STILL DO NOT HAVE MUCH CONFIDENCE IN THE
MESOSCALE DETAILS EVIDENT IN ANY PARTICULAR MODEL. WITH ABOVE
AVERAGE AGREEMENT WITH RESPECT TO THE OVERALL SYNOPTIC
EVOLUTION...DECIDED TO USE A CONSENSUS BLEND TO TREND THE EXISTING
FORECAST.
THIS SOLUTION WILL FEATURE STRONG RIDGES DEVELOPING OVER THE
WESTERN USA AS WELL AS THE WESTERN ATLANTIC. A SHORTWAVE MOVING
OVER THE GREAT LAKES INTO THE MISSISSIPPI VALLEY AND FORMS AN
ANOMALOUSLY STRONG CUTOFF LOW OVER THAT AREA. THIS UPPER LOW
EVENTUALLY EJECTS INTO THE /CANADIAN/ WESTERLIES DURING THE MIDDLE
OF NEXT WEEK.
THE DAILIES...
SATURDAY... ANOTHER SHORTWAVE ROTATES AROUND A GREAT LAKES UPPER
LOW AND CROSSES EASTERN NY/NEW ENGLAND. A SUPPORTING UPPER JET HAS
ITS RIGHT ENTRANCE REGION OVER NEW ENGLAND. A COLD FRONT STALLS
OVER OR NEAR THE REGION AND PROVIDES A FOCUS FOR LOW LEVEL
CONVERGENCE. PLENTY OF MOISTURE AVAILABLE WITH PRECIPITABLE WATER
VALUES BETWEEN 1.5 AND 2.0 INCHES...HIGHEST SOUTHEAST. WE WILL
FEATURE HIGHER POPS. WE WILL ALSO MENTION LOCALLY HEAVY DOWNPOURS
DUE TO THE HIGH MOISTURE CONTENT.
SUNDAY THROUGH THURSDAY...NOT MUCH CHANGE IN THE UPPER PATTERN
WITH CLOSED LOW TO THE WEST AND UPPER RIDGE TO THE EAST...AND A
MOIST SOUTH FLOW CONTINUING TO SUPPLY HIGH MOISTURE CONTENT AIR.
WE WILL CONTINUE TO FEATURE AT LEAST A CHANCE OF SHOWERS AND
THUNDERSTORMS IN THE FORECAST.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
TODAY...MODERATE CONFIDENCE. IFR/LIFR CONDITIONS EARLY...
IMPROVING TO MVFR/IFR EAST AND MVFR/PATCHY VFR WEST. OVERALL
IMPROVEMENTS BY LATE MORNING WEST TO EAST. HOWEVER SHOWERS AND
THUNDERSTORMS WILL REDEVELOP DURING THE LATE MORNING AND
AFTERNOON HOURS. THEREFORE MVFR OUT WEST IN ANY HEAVY
THUNDERSTORM.
TONIGHT...VFR/MVFR WILL SLOWLY DROP TO MVFR/IFR ACROSS THE REGION
IS LOW CLOUDS AND FOG. BEST REGION FOR LOWEST CONDITIONS WILL BE
ALONG THE SOUTH COAST.
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. CONFIDENT IN OVERALL
TRENDS HOWEVER LOW CONFIDENCE IN TIMING...PARTICULARLY WITH
CONVECTION.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF. CONFIDENT IN OVERALL
TRENDS HOWEVER LOW CONFIDENCE IN TIMING...PARTICULARLY WITH
CONVECTION.
OUTLOOK...SATURDAY THROUGH TUESDAY...
MODERATE CONFIDENCE.
PLENTY OF SHOWERS/TSTMS THIS WEEKEND WITH PERIODS OF MVFR
CIGS/VSBYS IN SHOWERS...SOME OF THEM QUITE HEAVY. THE VERY HUMID
AIRMASS WILL ALSO PRODUCE AREAS OF FOG AT NIGHT AND EARLY MORNING
WITH IFR CIGS/VSBYS IN ANY SUCH FOG. POTENTIAL FOR VSBYS NEAR 1/4
MILE AT TIMES.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT-TERM THROUGH FRIDAY...HIGH CONFIDENCE.
SHORT-TERM THROUGH FRIDAY NIGHT...HIGH CONFIDENCE.
SCA STILL CONTINUES ACROSS THE WATERS. CONTINUED TO UNDERCUT WNA
WAVE GUIDANCE BY ABOUT 10 PERCENT TO ACCOUNT FOR ITS SOUTHERLY
BIAS. OTHERWISE SHOWERS AND THUNDERSTORMS WILL CONTINUE TO
IMPACT THE WATERS TODAY AND INTO TONIGHT. MAIN THREATS WILL BE
LIGHTNING AND HEAVY DOWNPOURS IMPACTING VISIBILITIES.
OUTLOOK...SATURDAY THROUGH TUESDAY...
PERIODS OF SHOWERS/TSTMS/FOG EXPECTED WITH VERY HUMID AIR
CONTINUING. THERE WILL BE POOR VSBYS AT TIMES...AND 1/4 MILE
VSBYS IN FOG POSSIBLE EARLY EACH MORNING. SOUTH TO SOUTHWEST WINDS
THROUGH THE PERIOD. WIND GUSTS MAY APPROACH 25 KNOTS AT TIMES
SATURDAY...BUT BE PRIMARILY 20 KNOTS OR LESS. THE STEADY WIND
DIRECTION WILL HELP BUILD SEAS WITH WAVE HEIGHTS OF 5 TO 10 FEET
EXPECTED ACROSS THE OUTER COASTAL WATERS AND EXPOSED PORTIONS OF
THE SOUTHERN SOUNDS SUCH AS RI SOUND AND POSSIBLY BLOCK ISLAND
SOUND. A SMALL CRAFT ADVISORY WILL BE NEEDED FOR THESE ROUGH SEAS
THROUGH MIDWEEK...ESPECIALLY ACROSS THE OUTER COASTAL WATERS.
&&
.HYDROLOGY...
FLASH FLOOD WATCH CONTINUES THROUGH TODAY. RADAR ESTIMATED
RAINFALL RATES UP TO 6 IN PER HOUR WITHIN SOME OF THE STRONGER
THUNDERSTORMS LAST NIGHT. FORTUNATELY THESE THUNDERSTORMS REMAINED
PROGRESSIVE AND DID NOT LINGER OVER ANY ONE LOCATION FOR VERY
LONG. THESE RAINFALL RATES DO INDICATE THE POTENTIAL FOR HEAVY
RAINFALL WITHIN THIS SOUPY AIRMASS.
WILL NEED TO ESPECIALLY WATCH REGIONS OF HIGHER TERRAIN WHERE
UPSLOPE COULD ENHANCE THE RAINFALL AS WELL AS URBANIZED AREAS...
WHERE CONVECTIVE HEAVY RAIN MAY LEAD TO URBAN FLASH FLOODING.
&&
.CLIMATE...
WITH THE POTENTIAL FOR HEAVY RAIN TONIGHT INTO FRIDAY WE WILL BE
ADDING TO THE ALREADY HIGH MONTHLY TOTALS FOR RAIN. BELOW PLEASE
FIND THE TOP 10 WETTEST JUNE RAINFALL TOTALS FOR EACH OF OUR FOUR
CLIMATE SITES...THESE INCLUDE RAINFALL TOTALS FOR JUNE 2013 ENDING
AT MIDNIGHT THE MORNING OF JUNE 27.
BOSTON...
1. 13.20 INCHES IN 1982
2. 11.58 INCHES IN 1998
3. 10.09 INCHES IN 2006
4. 9.87 INCHES IN 2013
5. 9.13 INCHES IN 1931
6. 8.63 INCHES IN 1959
7. 8.05 INCHES IN 1922
8. 7.79 INCHES IN 1881
9. 7.74 INCHES IN 1986
10. 7.25 INCHES IN 1875
HARTFORD...
1. 13.60 INCHES IN 1982
2. 10.62 INCHES IN 2013
3. 9.66 INCHES IN 1972
4. 9.16 INCHES IN 2006
5. 8.08 INCHES IN 1937
6. 8.00 INCHES IN 1920
7. 7.79 INCHES IN 1948
8. 7.18 INCHES IN 1998
9. 6.92 INCHES IN 1922
10. 6.79 INCHES IN 1986
PROVIDENCE...
1. 11.08 INCHES IN 1982
2. 9.61 INCHES IN 1998
3. 9.39 INCHES IN 2013
4. 9.24 INCHES IN 2006
5. 7.21 INCHES IN 1938
6. 6.83 INCHES IN 1978
7. 6.80 INCHES IN 1920
8. 6.72 INCHES IN 2001
9. 6.58 INCHES IN 1922
10. 5.84 INCHES IN 1989
WORCESTER...
1. 12.17 INCHES IN 1982
2. 9.68 INCHES IN 1998
3. 9.55 INCHES IN 2013
4. 9.25 INCHES IN 1972
5. 8.31 INCHES IN 1922
6. 7.78 INCHES IN 1968
7. 7.44 INCHES IN 1903
8. 7.39 INCHES IN 1938
9. 7.21 INCHES IN 1986
10. 6.98 INCHES IN 1973 & 1935
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR CTZ002>004.
MA...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR MAZ002>021-
026.
NH...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR NHZ011-012-
015.
RI...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR RIZ001>007.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
ANZ231>234.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR ANZ235-237-
254>256.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR ANZ250.
&&
$$
SYNOPSIS...DUNTEN/BELK
NEAR TERM...BELK/DUNTEN
SHORT TERM...DUNTEN
LONG TERM...BELK
AVIATION...DUNTEN/BELK
MARINE...DUNTEN/BELK
HYDROLOGY...STAFF
CLIMATE...STAFF
AREA FORECAST DISCUSSION
NWS MIAMI FL
1041 AM EDT FRI JUN 28 2013
.UPDATE...
CHANGES ARE NOT BEING PLANNED AT THIS TIME FOR THE MORNING
UPDATES. THE 12Z MFL SOUNDING SHOWS THE WIND FIELD REMAINS VERY
WEAK BUT MODELS SHOW THIS PATTERN CHANGING THROUGHOUT THE DAY WITH
A SLIGHTLY MORE SW-NE STEERING FLOW DEVELOPING BY THIS AFTERNOON.
THE TROUGH DEEPENING OVER THE EASTERN U.S. HAS DEVELOPED A MORE
WESTERLY FLOW ACROSS SOUTH FLORIDA ABOVE 20K FEET AND THIS
REFLECTED IN THE POP AND WEATHER GRIDS BY SHOWING THE GREATEST
CHANCE OF CONVECTION OVER THE INTERIOR AND NORTHEAST PORTION OF
THE REGION. THE HRRR SHOWS SEA BREEZE DEVELOPMENT TYPE SHOWERS
NEAR BOTH COASTS AND THEN SPORADIC MOVEMENT INTO THIS AFTERNOON
BUT WITH A SLOW MIGRATION TOWARDS THE NORTHEAST. BASED ON LATER
CONDITIONS, THE MAIN AFTERNOON FORECAST MAY NEED TO BE CHANGED
SLIGHTLY FOR THE TRENDS AT THAT TIME.
KOB
&&
.PREV DISCUSSION... /ISSUED 807 AM EDT FRI JUN 28 2013/
AVIATION...
SOUTHERLY LOW LEVEL FLOW IS EXPECTED TODAY...WITH WESTERLY FLOW
ALOFT. SHOWERS AND THUNDERSTORMS ARE FORECAST TO START MAINLY OVER
THE INTERIOR ALONG THE SEA BREEZE BOUNDARIES. INCLUDED VCTS FOR ALL
TERMINALS AFTER 17Z. FOR APF INCLUDED VCTS THIS MORNING SINCE THE
FLOW IS SHOWING SIGNS OF BRINGING MOISTURE FROM THE GULF INTO THE
WEST COAST AS WINDS SHIFT MORE TO THE SOUTH AFTER SUNRISE. A FEW
SHOWERS ARE ALSO PRESENT THIS MORNING OVER THE ATLANTIC WATERS BUT
THEY ARE HAVING MORE DIFFICULTY PENETRATING INLAND AS THE FLOW
SHIFTS TO THE SOUTH. HOWEVER, INCLUDED VCSH FOR TMB UNTIL 17Z SINCE
SHOWERS CAN SPREAD INTO THE AREA FROM THE SOUTH.
PREV DISCUSSION... /ISSUED 246 AM EDT FRI JUN 28 2013/
DISCUSSION...
AN UPPER LEVEL TROUGH ACROSS THE EASTERN SEA BOARD WILL GET
REINFORCED AND DEEPEN INTO THE SOUTHEAST THIS WEEKEND INTO EARLY
NEXT WEEK AS AREAS OF VORTICITY ROTATE AROUND A MEAN CENTER...AND
A SERIES OF SHORTWAVES DIVE SOUTH OUT OF CANADA ON THE BACK SIDE
OF THE TROUGH. THE SURFACE RIDGE AXIS IS FORECAST TO BE LOCATED
ACROSS THE MIDDLE OF THE REGION AROUND 12Z THIS MORNING...AND
THEN WEAKEN AND SHIFT SOUTHEAST THROUGH THE WEEKEND. THIS WILL
ALLOW DEEP SOUTHWESTERLY FLOW TO DEVELOP ACROSS SOUTH FLORIDA
SATURDAY NIGHT INTO SUNDAY. SO THIS MEANS A GENERALLY WETTER
PATTERN FOR SOUTH FLORIDA THROUGH EARLY NEXT WEEK.
SOUTHERLY LOW LEVEL FLOW IS EXPECTED TODAY...WITH WESTERLY FLOW
ALOFT. MODELS ARE INDICATING A BIT LATER START TO THE DIURNALLY
DRIVEN CONVECTION...WITH SHOWERS AND THUNDERSTORMS STARTING MAINLY
OVER THE INTERIOR ALONG THE SEA BREEZE BOUNDARIES. THE FLOW OFF
THE SURFACE IS FORECAST TO VEER MORE TO THE SOUTHWEST AND WEST
THROUGHOUT THE DAY...AND STORMS SHOULD DRIFT BACK TO THE EAST
COAST IN THE MID/LATE AFTERNOON AND THROUGH THE EVENING HOURS. THE
CHANCE OF SHOWERS AND STORMS WILL BE LESS ACROSS THE NAPLES REGION
TODAY AS SHOWERS CONCENTRATE ACROSS THE INTERIOR AND MOVE EAST.
AN UNUSUALLY STRONG AND DEEP UPPER LEVEL TROUGH WILL CONTINUE TO DIG
INTO THE SOUTHEAST THROUGH THE WEEKEND. MODELS ARE INDICATING THAT
DRIER LOW LEVEL AIR WILL MOVE INTO THE REGION ON SATURDAY AS WINDS
SHIFT TO THE SOUTHWEST. IN ADDITION...THE BEST FORCING WILL BE
ACROSS CENTRAL FLORIDA AND EASTWARD INTO THE ATLANTIC ASSOCIATED
WITH THE UPPER TROUGH. GFS POPS HAVE THUS COME DOWN AS WELL. ONLY
DROPPED POPS SLIGHTLY FOR SATURDAY...WITH THE BEST CHANCE ACROSS
THE LAKE REGION AND PALM BEACH COUNTY. DEEPER MOISTURE IS EXPECTED
TO BEGIN MOVING FROM THE SOUTH SATURDAY NIGHT...AND NOCTURNAL
SHOWERS AND THUNDERSTORMS ARE POSSIBLE ACROSS THE
REGION...ESPECIALLY ACROSS THE SOUTH. AS THE DEEPER MOISTURE
CONTINUES ACROSS THE REGION ON SUNDAY...CLOUD COVER WILL
INCREASE...BUT NUMEROUS SHOWERS AND THUNDERSTORMS CAN BE EXPECTED
AREA WIDE. WITH THE SOUTHWESTERLY FLOW AT ALL LEVELS...ABOVE NORMAL
TEMPERATURES ARE NORMALLY THE CASE FOR THE EAST COAST AREAS DUE TO
THE ATLANTIC SEA BREEZE BEING HELD OFFSHORE UNTIL THE AFTERNOON.
HOWEVER...THE LOWERING HEIGHTS THROUGH THE WEEKEND...INCREASING
CLOUD COVER...AND RAINFALL ESPECIALLY ON SUNDAY SHOULD KEEP
TEMPERATURES NEAR NORMAL THROUGH THE WEEKEND.
THE UPPER LEVEL TROUGH/CUTOFF UPPER LOW WILL BEGIN TO RETROGRADE TO
THE WEST IN THE EARLY TO THE MIDDLE PART OF NEXT WEEK...AND THE FLOW
WILL BACK TO THE SOUTH AND THEN SOUTHEAST. SO THE BEST RAIN
CHANCES FOR THE AFTERNOON HOURS ARE FORECAST TO SHIFT BACK TO
TOWARDS THE INTERIOR AND GULF COAST.
MARINE...
A GENERAL SOUTH WIND WILL CONTINUE TODAY AND THEN
VEER TO THE SOUTHWEST OVER THE WEEKEND AT SPEEDS OF 15 KNOTS OR
LESS. THUS, SEAS WILL REMAIN WELL BELOW ADVISORY LEVELS BUT THERE
COULD BE SOME LOCALLY ROUGH SEAS NEAR STRONGER THUNDERSTORMS
MAINLY OVER LAKE OKEECHOBEE AND NEAR BOTH COASTS OF THE PENINSULA.
FIRE WEATHER...
A WET PATTERN IS IN STORE FOR SOUTH FLORIDA THROUGH THE WEEKEND
AND INTO EARLY NEXT WEEK. HIGH RELATIVE HUMIDITY VALUES ARE
EXPECTED THROUGH THE PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 89 77 88 77 / 60 50 50 30
FORT LAUDERDALE 88 79 89 79 / 60 50 50 40
MIAMI 89 77 90 78 / 50 40 40 40
NAPLES 90 75 89 76 / 30 20 40 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1011 AM CDT FRI JUN 28 2013
.UPDATE...
ISSUED AT 1006 AM CDT FRI JUN 28 2013
BASED ON DATA THROUGH 15Z...THERMALS SHOULD BEGIN DEVELOPING WITHIN
THE HOUR WITH DIURNAL CU BY MID DAY. AS SUCH THE REMAINDER OF THE
MORNING WILL REMAIN DRY ACROSS THE AREA.
RAP TRENDS INDICATE THE CONVECTIVE TEMPERATURE WILL SLOWLY DROP
DURING THE DAY WHICH WHEN COMBINED WITH THE APPROACHING VORT MAX
SHOULD INITIATE CONVECTION DURING THE AFTERNOON. CONVECTION IS
EXPECTED TO BE IN THE FORM OF SHOWERS WITH SOME THUNDERSTORMS.
CONVECTION WILL CONTINUE INTO THE EVENING WITH THE THUNDERSTORMS
DISSIPATING WITH SUNSET. HOWEVER...THE PROXIMITY OF THE COOL POOL
ALOFT AND UPPER LOW SHOULD KEEP SHOWERS GOING WELL INTO THE
EVENING AND OVERNIGHT HOURS WITH DECREASING COVERAGE. ..08..
&&
.SYNOPSIS...
ISSUED AT 300 AM CDT FRI JUN 28 2013
WATER VAPOR LOOPS SHOWED A BROAD UPPER TROUGH ACROSS THE GREAT
LAKES WITH A CLOSED LOW ON THE NORTHERN TIP OF LAKE SUPERIOR. A
STRONG SHORT WAVE/VORT MAX WAS LOCATED IN NORTHEAST MN. A FEW
SHOWERS WERE NOTED IN CENTRAL WI. OTHERWISE CLEAR SKIES WERE
ACROSS THE DVN CWA WHILE A LARGE MCS WAS COVERING SOUTHERN MO
AHEAD OF A COLD FRONT. CURRENT TEMPERATURES IN THE DVN CWA RANGED
FROM THE MID 60S TO LOWER 70S WITH DEWPOINTS IN THE UPPER 50S NW
TO UPPER 60S SE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 300 AM CDT FRI JUN 28 2013
FORECAST FOCUS ON SHOWER CHANCES...CLOUD TRENDS AND TEMPERATURES.
TODAY...OPERATIONAL MODELS SLIDE THE GREAT LAKES TROUGH SOUTHWARD
INTO OUR REGION WITH THE RAP DEPICTING A STRONG VORT MAX MOVING
FROM NORTHEAST MN INTO NORTHERN IL THIS AFTERNOON. WITH COOLING
TEMPERATURES ALOFT COMBINED WITH DAYTIME HEATING INSTABILITY WILL
INCREASE. HAVE CONFINED POPS TO THIS AFTERNOON AND ALSO ACROSS OUR
NORTHEAST HALF CWA CLOSER TO THE TRACK OF THE VORT MAX. THE HRRR
MESO MODEL DEPICTS THE POPCORN DESCRIPTION OF THE SCATTERED INSTABILITY
SHOWERS (AND A FEW THUNDERSTORMS) QUITE WELL. THERE WILL BE PLENTY OF
SUNSHINE FOR MOST OF THIS MORNING BUT CLOUDS WILL DEVELOP/FILL AS
THE CONVECTIVE TEMPERATURE IS REACHED. MAXIMUM TEMPERATURES WILL
RANGE FROM THE UPPER 70S NORTH TO THE MID 80S SOUTH BUT HUMIDITY
LEVELS WILL BE THANKFULLY LOWER COMPARED TO THE LAST FEW DAYS.
TONIGHT...WITH THE UPPER TROUGH OVER THE AREA WILL CONTINUE WITH
CHANCE POPS AS SKIES WILL BE MOSTLY CLOUDY OR BECOME MOSTLY CLOUDY.
HOWEVER...WITH THE LOSS OF HEATING/BETTER INSTABILITY THE COVERAGE OF
SHOWERS WILL DECREASE OVERNIGHT. MINIMUM TEMPERATURES SHOULD BE IN
THE LOWER 60S AT MOST LOCATIONS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 300 AM CDT FRI JUN 28 2013
A DIGGING UPPER TROF OVER THE EASTERN U.S IS FORECAST TO CLOSE OFF
OVER THE OHIO VALLEY BY LATE IN THE WEEKEND. THEN...MODELS ARE IN
AGREEMENT THAT THE CLOSED LOW WILL RETROGRADE INTO THE MID
MISSISSIPPI VALLEY EARLY IN THE WEEK AND REMAIN THERE...THEN
GRADUALLY FILLING DURING THE LATTER HALF OF THE WEEK.
THIS PATTERN WILL SUPPORT BELOW NORMAL TEMPERATURES THROUGH THE
FORECAST PERIOD WITH HIGHS GENERALLY IN THE 70S TO AROUND 80 AND
LOWS...ESPECIALLY EARLY IN THE WEEK...IN THE 50S.
MOST DAYS WILL HAVE AT LEAST A LOW THREAT OF RAIN.
HOWEVER...AS STATED IN THE PREVIOUS DISCUSSION...THE RAIN THREAT
WILL BE LIMITED TO JUST A FEW HOURS EACH DAY.
THE BETTER CHANCE OF RAIN DURING THE PERIOD WILL BE SATURDAY AS A
SERIES OF S/WS DROP INTO THE DEVELOPING TROF TO OUR EAST. THE
BETTER UPPER FORCING APPEARS TO BE JUST EAST OF THE
FORECAST AREA...SO KEPT THE HIGHER CHANCE AND LIKELY POPS NEAR AND
EAST OF THE MISSISSIPPI RIVER. THE RAIN THREAT WILL DIMINISH
SATURDAY NIGHT AND SUNDAY AS DRIER LOW LEVEL AIR FILTERS IN FROM THE
NORTH. THE DRY WEATHER SHOULD LAST THROUGH MONDAY THEN A LOW RAIN
THREAT RETURNS MONDAY NIGHT THROUGH THE END OF THE WEEK AS THE UPPER
LOW BACKS INTO THE REGION FROM THE EAST. THIS WILL SUPPORT MAINLY
AFTERNOON ISOLATED TO SCATTERED SHOWERS OR THUNDERSTORMS. SINCE ANY
SHRA/TSRA ACTIVITY WILL PROBABLY BE TIED TO AFTERNOON HEATING...HAVE
LIMITED THE POPS TO THE DAYTIME HOURS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 627 AM CDT FRI JUN 28 2013
VFR CONDS TODAY AND TONIGHT. SCATTERED SHOWERS AND A FEW THUNDERSTORMS
WILL DEVELOP THIS AFTERNOON ACROSS PORTIONS OF EASTERN IA AND
NORTHWEST IL. A FEW SHOWERS MAY LINGER INTO TONIGHT. NORTHWEST
WINDS INCREASING TO 15 TO 20 KNOTS WITH GUSTS TO 25 KNOTS THIS AFTERNOON.
NORTHWEST WINDS AROUND 10 KNOTS TONIGHT.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...08
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...DLF
AVIATION...HAASE
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
636 AM CDT FRI JUN 28 2013
.SYNOPSIS...
ISSUED AT 300 AM CDT FRI JUN 28 2013
WATER VAPOR LOOPS SHOWED A BROAD UPPER TROUGH ACROSS THE GREAT
LAKES WITH A CLOSED LOW ON THE NORTHERN TIP OF LAKE SUPERIOR. A
STRONG SHORT WAVE/VORT MAX WAS LOCATED IN NORTHEAST MN. A FEW
SHOWERS WERE NOTED IN CENTRAL WI. OTHERWISE CLEAR SKIES WERE
ACROSS THE DVN CWA WHILE A LARGE MCS WAS COVERING SOUTHERN MO
AHEAD OF A COLD FRONT. CURRENT TEMPERATURES IN THE DVN CWA RANGED
FROM THE MID 60S TO LOWER 70S WITH DEWPOINTS IN THE UPPER 50S NW
TO UPPER 60S SE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 300 AM CDT FRI JUN 28 2013
FORECAST FOCUS ON SHOWER CHANCES...CLOUD TRENDS AND TEMPERATURES.
TODAY...OPERATIONAL MODELS SLIDE THE GREAT LAKES TROUGH SOUTHWARD
INTO OUR REGION WITH THE RAP DEPICTING A STRONG VORT MAX MOVING
FROM NORTHEAST MN INTO NORTHERN IL THIS AFTERNOON. WITH COOLING
TEMPERATURES ALOFT COMBINED WITH DAYTIME HEATING INSTABILITY WILL
INCREASE. HAVE CONFINED POPS TO THIS AFTERNOON AND ALSO ACROSS OUR
NORTHEAST HALF CWA CLOSER TO THE TRACK OF THE VORT MAX. THE HRRR
MESO MODEL DEPICTS THE POPCORN DESCRIPTION OF THE SCATTERED INSTABILITY
SHOWERS (AND A FEW THUNDERSTORMS) QUITE WELL. THERE WILL BE PLENTY OF
SUNSHINE FOR MOST OF THIS MORNING BUT CLOUDS WILL DEVELOP/FILL AS
THE CONVECTIVE TEMPERATURE IS REACHED. MAXIMUM TEMPERATURES WILL
RANGE FROM THE UPPER 70S NORTH TO THE MID 80S SOUTH BUT HUMIDITY
LEVELS WILL BE THANKFULLY LOWER COMPARED TO THE LAST FEW DAYS.
TONIGHT...WITH THE UPPER TROUGH OVER THE AREA WILL CONTINUE WITH
CHANCE POPS AS SKIES WILL BE MOSTLY CLOUDY OR BECOME MOSTLY CLOUDY.
HOWEVER...WITH THE LOSS OF HEATING/BETTER INSTABILITY THE COVERAGE OF
SHOWERS WILL DECREASE OVERNIGHT. MINIMUM TEMPERATURES SHOULD BE IN
THE LOWER 60S AT MOST LOCATIONS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 300 AM CDT FRI JUN 28 2013
A DIGGING UPPER TROF OVER THE EASTERN U.S IS FORECAST TO CLOSE OFF
OVER THE OHIO VALLEY BY LATE IN THE WEEKEND. THEN...MODELS ARE IN
AGREEMENT THAT THE CLOSED LOW WILL RETROGRADE INTO THE MID
MISSISSIPPI VALLEY EARLY IN THE WEEK AND REMAIN THERE...THEN
GRADUALLY FILLING DURING THE LATTER HALF OF THE WEEK.
THIS PATTERN WILL SUPPORT BELOW NORMAL TEMPERATURES THROUGH THE
FORECAST PERIOD WITH HIGHS GENERALLY IN THE 70S TO AROUND 80 AND
LOWS...ESPECIALLY EARLY IN THE WEEK...IN THE 50S.
MOST DAYS WILL HAVE AT LEAST A LOW THREAT OF RAIN.
HOWEVER...AS STATED IN THE PREVIOUS DISCUSSION...THE RAIN THREAT
WILL BE LIMITED TO JUST A FEW HOURS EACH DAY.
THE BETTER CHANCE OF RAIN DURING THE PERIOD WILL BE SATURDAY AS A
SERIES OF S/WS DROP INTO THE DEVELOPING TROF TO OUR EAST. THE
BETTER UPPER FORCING APPEARS TO BE JUST EAST OF THE
FORECAST AREA...SO KEPT THE HIGHER CHANCE AND LIKELY POPS NEAR AND
EAST OF THE MISSISSIPPI RIVER. THE RAIN THREAT WILL DIMINISH
SATURDAY NIGHT AND SUNDAY AS DRIER LOW LEVEL AIR FILTERS IN FROM THE
NORTH. THE DRY WEATHER SHOULD LAST THROUGH MONDAY THEN A LOW RAIN
THREAT RETURNS MONDAY NIGHT THROUGH THE END OF THE WEEK AS THE UPPER
LOW BACKS INTO THE REGION FROM THE EAST. THIS WILL SUPPORT MAINLY
AFTERNOON ISOLATED TO SCATTERED SHOWERS OR THUNDERSTORMS. SINCE ANY
SHRA/TSRA ACTIVITY WILL PROBABLY BE TIED TO AFTERNOON HEATING...HAVE
LIMITED THE POPS TO THE DAYTIME HOURS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 627 AM CDT FRI JUN 28 2013
VFR CONDS TODAY AND TONIGHT. SCATTERED SHOWERS AND A FEW THUNDERSTORMS
WILL DEVELOP THIS AFTERNOON ACROSS PORTIONS OF EASTERN IA AND
NORTHWEST IL. A FEW SHOWERS MAY LINGER INTO TONIGHT. NORTHWEST
WINDS INCREASING TO 15 TO 20 KNOTS WITH GUSTS TO 25 KNOTS THIS AFTERNOON.
NORTHWEST WINDS AROUND 10 KNOTS TONIGHT.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...DLF
AVIATION...HAASE
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
740 AM EDT FRI JUN 28 2013
LATEST UPDATE...
UPDATE/AVIATION
.SYNOPSIS...
ISSUED AT 328 AM EDT FRI JUN 28 2013
CONDITIONS TODAY WILL BE FAIRLY SIMILAR TO WHAT HAPPENED DURING THE
DAY ON THURSDAY. SCATTERED SHOWERS AND STORMS WILL BEGIN TO DEVELOP
LATE THIS MORNING AND CONTINUE INTO THE EARLY EVENING HOURS. THE
BEST CHANCE FOR RAINFALL WILL OCCUR AWAY FROM LAKE MICHIGAN. PERIODS
OF SUNSHINE CAN BE EXPECTED IN BETWEEN SHOWERS THAT OCCUR. LESS IN
THE WAY OF RAINFALL IS EXPECTED ON SATURDAY...ALTHOUGH THE CHANCE
WILL STILL EXIST SATURDAY AFTERNOON AND EVENING. MOST LOCATIONS
SHOULD STAY DRY ON SUNDAY WITH MILD TEMPERATURES WELL INTO THE 70S
EXPECTED FOR HIGHS.
&&
.UPDATE...
ISSUED AT 740 AM EDT FRI JUN 28 2013
I UPDATED THE ZONES TO REFLECT THE AREA OF SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS NOW MOVING TOWARD MOP. THIS AREA SHOULD BE
EAST OF THE CWA BY 10 AM. RAP SOUNDINGS SHOW A MOIST LAYER BETWEEN
800 AND 600 MB BEING THE KICK-0FF FOR THESE SHOWERS WITH IN
COMBINATION WITH THE EDGE OF THE UPPER COLD POOL MOVING IN.
THE NEXT UPSTREAM SHORTWAVE WILL MOVE INTO THE AREA BY EARLY
AFTERNOON AND THE COMBINATION OF THAT THE COMBINED LAKE BREEZES
FROM LAKE HURON AND LAKE MICHIGAN SHOULD KEEP THE SHOWERS AND
THUNDERSTORMS MOSTLY EAST OF GRAND RAPIDS.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 328 AM EDT FRI JUN 28 2013
THE MAIN FOCUS OF THE FORECAST THROUGH THE WEEKEND REMAINS
CONVECTIVE TRENDS WITH THE UPPER LOW PARKED OVER THE REGION. THE
GENERAL TREND OF THE FCST REMAINS MAINLY UNCHANGED.
IT APPEARS THAT WE WILL HAVE SIMILAR CONDITIONS DURING THE DAY TODAY
AS COMPARED TO YESTERDAY REGARDING CONVECTION POTENTIAL. CONVECTIVE
DEVELOPMENT LOOKS LIKE IT WILL ONCE AGAIN BEGIN TO FIRE LATE IN THE
MORNING HOURS ACROSS THE NE CORNER OF THE CWFA. THIS IS DUE TO SFC
CONVERGENCE MAXIMIZED IN THAT LOCATION RESULTING FROM A SFC TROUGH
THIS IS DROPPING SOUTH THROUGH THE AREA. THE SFC TROUGH IS SUPPORTED
BY A LOBE OF THE NEWLY FORMED UPPER LOW DROPPING SOUTH.
THE SFC CONVERGENCE/UPPER WAVE WILL BE ACTING ON ML CAPES OF 1000+
J/KG BY 18Z THIS AFTERNOON. IN ADDITION...A SOMEWHAT WRLY COMPONENT
TO THE WIND WILL CONVERGE WITH A DEVELOPING LAKE BREEZE FROM LAKE
HURON/SAGINAW BAY TO ONLY HELP THE CAUSE. SEVERE WEATHER IS NOT
EXPECTED AS THE DEEP LAYER SHEAR IS ABOUT NIL WITH THE UPPER LOW
ALMOST DIRECTLY OVER THE AREA. WE CAN EXPECT SOME PULSE TYPE STORMS
WITH SOME POSSIBLE HAIL AS THE FREEZING LEVELS COME DOWN TO AROUND
11K FT OR SO. WE CAN NOT RULE OUT A DRY MICROBURST OF SOME
SUB-SEVERE WINDS. LOCALLY HEAVY RAINFALL WILL ALSO BE POSSIBLE WITH
THE SLOW MOVEMENT OF ANY STORMS. THE LAKESHORE WILL HAVE THE LEAST
CHC OF STORMS DUE TO THE STABILIZING EFFECTS OF LAKE MICHIGAN. WE
CAN NOT RULE OUT SOMETHING SURVIVING THE TRIP FROM WISCONSIN...BUT
THIS IS NOT LIKELY.
THE LOBE OF THE UPPER LOW WILL ALMOST BE THROUGH THE CWFA FIRST
THING ON SAT MORNING AT 12Z. IT WILL DROP SOUTH BY AFTERNOON LEAVING
SOME SHORT WAVE RIDGING IN THE WAKE OVER THE CWFA. THIS COMBINED
WITH SOME DRIER AIR ADVECTING IN FROM THE NE WILL LIMIT ML CAPES
FROM GETTING MUCH HIGHER THAN 500 J/KG DURING THE DAY ON SAT. THE
FLOW WILL BECOME NE WHICH WILL TAKE OUT THE STABILIZING EFFECTS FROM
LAKE MICHIGAN. IN FACT...SOME OF THE BEST CHCS OF SHOWERS/STORMS ON
SAT MIGHT BE ALONG THE LAKE BREEZE WITH THE W AND NE WINDS
CONVERGING AT A GOOD ANGLE. COVERAGE AND INTENSITY SHOULD BE LOWER
THAN TODAY. SEVERE WEATHER IS ONCE AGAIN NOT EXPECTED WITH SHEAR
VALUES BELOW 20 KNOTS.
THE THREAT FOR SHOWERS AND STORMS GOES DOWN EVEN MORE ON SUN AS EVEN
DRIER AIR ADVECTS IN AT THE LOWER LEVELS. ML CAPES ARE FCST TO ONLY
MAKE IT TO AROUND 200 J/KG AT BEST. THIS WILL KEEP A LID ON MOST
CONVECTION THAT TRIES TO DEVELOP...EXCEPT MAYBE RIGHT ALONG THE SRN
BORDER CLOSER TO THE MID LEVEL COLD POOL.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 328 AM EDT FRI JUN 28 2013
IT WOULD SEEM COOLER THAN NORMAL TEMPERATURES AND AFTERNOON AND
EVENING CONVECTION WILL BE THE PRIMARY WEATHER FEATURE THROUGH THIS
MOST OF THE COMING WEEK.
OVERALL THERE IS GOOD MODEL AGREEMENT WITH BOTH RUN TO RUN AND MODEL
TO MODEL OVER CONUS THROUGH THIS COMING WEEK. HOWEVER BY WEDNESDAY
THERE IS A CURIOUS DIFFERENCE OVER EASTERN CANADA BY BETWEEN THE
ECMWF AND THE GFS IN THAT THE ECMWF IS MUCH STRONGER AND DEEPER WITH
SYSTEM THAT DIVES SOUTH SOUTHEAST INTO QUEBEC. THIS WOULD SUGGEST A
MUCH STRONGER COLD FRONT IS HEADING SOUTH TOWARD THE NORTHERN
BOARDER STATES LATE IN THE WEEK THAN SHOWN ON THE GFS. HOWEVER FOR
THIS FORECAST TIME PERIOD THIS IS MORE OF A CURIOSITY THAN SOMETHING
WE HAVE TO WATCH CLOSELY.
THE MORE SIGNIFICANT ISSUE IS WE HAVE SPLIT FLOW OVER NORTH AMERICA
WITH THE NORTHERN BRANCH NEAR 70N AND THE SOUTHERN BRANCH CLIMBING
OVER THE WESTERN RIDGE NEAR 115W INTO SOUTHERN BRITISH COLUMBIA AND
MANITOBA... THEN DIVING SOUTHEAST TO NEAR THE GULF COAST WEST OF
MISSOURI RIVER AND THEN HEADING BACK NORTH TO NEW ENGLAND ALONG THE
EAST COAST. THIS DIP IN THE JET STREAM IS ANOMALOUS FOR THIS TIME OF
YEAR IS THE RESULT OF AN UPPER LOW THAT SOUTHERN GREAT LAKES THAT
SLOWLY RETROGRADES WEST OF THE MISSISSIPPI RIVER BY WEDNESDAY AS
SHORTWAVE ENERGY FROM THE SOUTHERN BRANCH DIVES INTO THE WESTERN
SIDE OF THE LONG WAVE TROUGH.
WHAT THIS DOES IS TO KEEP SOUTHWEST MICHIGAN IN OR NEAR CLOSED UPPER
LOW THROUGH MOST OF THE COMING WEEK. IN SUNDAY NIGHT TO MONDAY
PERIOD THE UPPER LOW IS FAR ENOUGH SOUTH AND EAST OF OUR AREA SO AS
TO ALLOW FOR SOME SURFACE RIDGING AND NORTHEAST SURFACE WINDS
BRINGING IN DRY SURFACE AIR. SO THAT IS A TIME WHEN THE
PRECIPITATION THREAT WOULD BE LOWEST. BY TUESDAY AND WEDNESDAY AS
THE SYSTEM REGRADES... THE SOUTHERLY FLOW ALOFT ON THE EAST SIDE OF
THE SYSTEM BRINGS MOISTURE BACK INTO THE REGION WITH DEEP
INSTABILITY THAT WILL LEAD TO LARGELY AFTERNOON AND EVENING
THUNDERSTORMS. THE SHEAR REMAINS LOW SO THE SEVERE STORM THREAT IS
LOW. BY JULY 4TH THE ECMWF SUGGEST UPPER RIDGING TRYING TO BUILD IN
WHILE THE GFS KEEP UPPER TROUGH OVER THE AREA. BOTH MODELS BUILD
IN AN UPPER RIDGE BY FRIDAY SO BY THEN IT SHOULD DRY OUT AND WARM UP
SOME.
THE BOTTOM LINE IS THE BEST CHANCE OF SHOWERS AND THUNDERSTORMS IS
TUE AND WEDNESDAY... THE DRIEST WEATHER SHOULD BE MONDAY AND FRIDAY.
TEMPERATURES WILL RUN BELOW NORMAL THROUGH FRIDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 740 AM EDT FRI JUN 28 2013
LOW CLOUDS ARE ALREADY MIXING OUT SO VFR CIGS/VSBY ARE EXPECTED
MOST OF THE DAY INTO THIS EVENING. THE PUSH OF LOW LEVEL COLD
AIR IN COMBINATION WITH THE 850 MB TROUGH COMING THROUGH WILL
BRING LOW CLOUDS AND SOME LIGHT FOG TO THE TAF SITES AFTER 03Z
SATURDAY. I WOULD EXPECT IFR CIGS/VSBY AT MOST OF THE TAF SITES BY
10Z OR SO SATURDAY MORNING.
THE CONVECTION TODAY WILL BE TO HIT AND MISS TO PUT IN THE TAFS AT
THIS POINT SO I HAVE VCTS THIS AFTERNOON AND VCSH THIS EVENING.
MOST OF THE CONVECTION WILL BE NEAR AND EAST OF LANSING DUE TO THE
WEST NORTHWEST WIND OFF LAKE MICHIGAN PUSHING THE CONVERGENCE AREA
WELL INLAND.
&&
.MARINE...
ISSUED AT 328 AM EDT FRI JUN 28 2013
NO MARINE HEADLINES ARE EXPECTED THROUGH THE WEEKEND. WE WILL SEE
WINDS GENERALLY RUNNING AROUND 10 TO 15 KNOTS EACH DAY FROM TODAY
THROUGH SUNDAY. THIS WILL PRODUCE WAVES OF GENERALLY 1 TO LOCALLY 3
FEET WITH THE HIGHEST WAVES EXPECTED SOUTH DUE TO THE NRLY FETCH.
&&
.HYDROLOGY...
ISSUED AT 328 AM EDT FRI JUN 28 2013
NO WIDESPREAD HYDROLOGY HEADLINES EXPECTED THROUGH EARLY NEXT WEEK.
WE WILL HAVE TO WATCH FOR SOME LOCALLY HEAVY RAINS FOR TODAY...
ALTHOUGH THE THREAT IS A LITTLE LOWER COMPARED TO THU. WE WILL SEE
DIURNAL SHOWERS AND STORMS DEVELOP ONCE AGAIN WITH VERY SLOW
MOVEMENT EXPECTED DUE TO THE LACK OF WIND IN THE CLOUD LAYER.
PRECIPITABLE WATER HAS DROPPED A LITTLE AS THE BEST MOISTURE AXIS
HAS MOVED AWAY AND DRIER AIR IS SLOWLY FILTERING IN. SOME FLOOD
ADVISORIES WILL BE POSSIBLE WHERE CONVECTION SITS FOR LONGER PERIOD
OF TIMES. THE THREAT WILL BECOME MUCH LOWER FOR THE REMAINDER OF THE
WEEKEND.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...WDM
SYNOPSIS...NJJ
SHORT TERM...NJJ
LONG TERM...WDM
AVIATION...WDM
HYDROLOGY...NJJ
MARINE...NJJ
AREA FORECAST DISCUSSION...UPDATED
NWS GLASGOW MT
929 AM MDT FRI JUN 28 2013
.SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH SUNDAY...
SENT AN UPDATE THIS MORNING FOR SOME VERY MINOR CHANGES. CHOSE TO
SCALE BACK THE SLIGHT CHANCE POPS TOWARD THE NORTHEAST TO NOT
COVER AS MUCH OF THE CWA...FOLLOWING THE MOST RECENT HI-RES MODEL
UPDATES. MADE OTHER SMALL ADJUSTMENTS TO SKY COVER...TEMPS...AND
WINDS. IT WILL BE VERY INSTRUCTIVE AND TELLING TO SEE IF THE
ISOLATED SHOWERS AND POSSIBLY A THUNDERSTORM OR TWO BEING RESOLVED
IN THE HI-RES MODELS...THE HRRR FOR EXAMPLE...ACTUALLY RESULT IN
SOME PRECIPITATION REACHING THE GROUND TODAY...OR IF IT WILL JUST
BE VIRGA SHOWERS. I WILL MAKE A FEW PHONE CALLS TO TRY AND GET
SOME GROUND TRUTH IN ORDER TO ASCERTAIN THE APPROPRIATE LEVEL OF
MODEL CONFIDENCE. BMICKELSON
PREVIOUS SHORT TERM DISCUSSION...UPPER RIDGE CURRENTLY COVERING
THE WESTERN HALF OF THE U.S. WILL REMAIN IN PLACE FOR THE MOST
PART THROUGH THE WEEKEND. THE RIDGE WILL GAIN SOME AMPLITUDE WITH
THE TOP OF THE RIDGE MOVING NORTH TODAY AND SATURDAY. WITH ONE
EXCEPTION...EXPECT DRY WEATHER THROUGH SATURDAY WITH TEMPERATURES
AT OR SLIGHTLY ABOVE NORMAL. WINDS WILL BE SOMEWHAT LIGHTER TODAY
THAN YESTERDAY AS SURFACE HIGH MOVES THROUGH EASTERN MONTANA.
THE EXCEPTION TO THE DRY WEATHER WILL BE A WEAK SHORTWAVE TODAY
THAT MOVES ACROSS THE TOP OF THE RIDGE IN SOUTHERN ALBERTA AND
GOES THROUGH THE NE CORNER OF MONTANA THIS AFTERNOON. IT LOOKS
LIKE THERE WILL BE THE POSSIBILITY OF THE ATMOSPHERE BEING
UNSTABLE ENOUGH IN THE NORTHEAST ZONES THIS AFTERNOON THAT A FEW ISOLATED
THUNDERSTORMS COULD DEVELOP. WILL ADD THAT TO THE FORECAST FOR
THIS AFTERNOON.
WINDS WILL TURN TO THE EAST OR SOUTHEAST TONIGHT AND SATURDAY AS
THE SURFACE HIGH MOVES TO THE EAST AND LEE SIDE TROUGH DEVELOPS
OVER CENTRAL MONTANA. AIR MASS IN CENTRAL MONTANA WILL BE SOMEWHAT
UNSTABLE ON SATURDAY WHICH WILL ALLOW SOME MOUNTAIN BASED
CONVECTION TO DEVELOP. AT THIS POINT...IT LOOKS LIKE ANY STORMS
THAT DO DEVELOP IN THE MOUNTAINS ON SATURDAY WILL DISSIPATE
BEFORE REACHING NORTHEAST MONTANA WITH AIR MASS BEING STABLE THERE.
ON SUNDAY...A SHORTWAVE MOVING THROUGH ALBERTA WILL FLATTEN THE
RIDGE SOMEWHAT. AIR MASS BECOMES SOMEWHAT UNSTABLE IN NORTHEAST
MONTANA IN THE AFTERNOON WHICH WILL GIVE ANY STORMS THAT DEVELOP
IN THE MOUNTAINS TO THE WEST A BETTER CHANCE OF HOLDING TOGETHER
AS THEY MOVE TO THE EAST. WILL MENTION A SLIGHT CHANCE OF
THUNDERSTORMS IN THE AFTERNOON. FORRESTER
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY...
SUNDAY NIGHT THROUGH TUESDAY...MODEL GUIDANCE IS IN EXCELLENT
AGREEMENT KEEPING A HIGHLY AMPLIFIED UPPER LEVEL RIDGE ACROSS THE
WESTERN U.S. LEADING TO LARGE SCALE SUBSIDENCE AND THEREFORE DRY
CONDITIONS FOR NORTHEAST MONTANA. INCLUDED A SLIGHT CHANCE POPS
MENTION IS SOME LOCATIONS WHERE MINOR DISTURBANCES MAY LEAD TO
ENHANCED VERTICAL ASCENT AS THEY PROPAGATE THROUGH IN NORTHERLY FLOW
ALOFT THROUGH THE CWA ON THE EASTERN PERIPHERY OF THE RIDGE. WILL
EXPECT SEASONAL TO A FEW DEGREES ABOVE SEASONAL TEMPERATURES WITH
THE FORECAST REGION SITUATED IN THIS RIDGING PATTERN ALONG WITH
RISING 850MB TEMPERATURES.
TUESDAY NIGHT AND BEYOND...AN UPPER LEVEL SHORTWAVE FEATURE IS
ADVERTISED IN BOTH THE 00Z ECMWF AND GFS TO DIVE DOWN FROM
SASKATCHEWAN AND INTO THE DAKOTAS BEFORE RETROGRADING TOWARD
NORTHEAST MONTANA. THE LARGE SCALE RIDGING WILL ERODE ONLY VERY
GRADUALLY AND WILL OFFER GREAT RESISTANCE TO THIS SHORTWAVE
FEATURE. THEREFORE NOT OVERLY EXCITED ABOUT INSERTING HIGHER POPS
INTO THE GRIDS AT THIS TIME. HOWEVER...DID FEEL COMFORTABLE MAKING
SOME REFINEMENTS IN THAT FROM THE MIDDLE OF THE WEEK ONWARD...THE
HIGHEST POPS ARE INCLUDED IN THE EASTERN ZONES...WITH POPS
TRENDING DOWN TO SLIGHT CHANCE MENTION OR LOWER FURTHER TO THE
WEST. BY THE END OF THE WEEK...CONFINED MENTION TO JUST THE
SOUTHERN ZONES TRENDED TEMPERATURES DOWN IN THE MIDDLE PORTION OF
NEXT WEEK WITH LOWERING 850MB TEMPERATURES AND DECREASING
THICKNESSES IN THE EASTERN ZONES AS THE UPPER LEVEL SHORTWAVE
MAKES A PENETRATION INTO THE RIDGING. MODELS DO BEGIN TO INDICATE
A RETURN OF AN UPPER LEVEL RIDGE DEVELOPING BY THE END OF NEXT
WEEK OR THE WEEKEND...BUT GIVEN HOW FAR OUT THAT IS IN THE
FORECAST PERIOD...WILL NOT CONCERN OVER THE DETAILS RIGHT NOW. DID
TICK TEMPERATURES UPWARD JUST A TOUCH ON FRIDAY THOUGH TO REFLECT
THIS IDEA. IT IS SURPRISING HOWEVER THAT THERE IS SUCH EXCELLENT
MODEL AGREEMENT THIS FAR OUT AND THAT AT LEAST LEADS TO HIGH
CONFIDENCE IN THE EXTENDED FORECAST.
ONE THING OF INTEREST TO CONSIDER THOUGH LATE NEXT WEEK OR WEEKEND IS
MODELS BRINGING IN AN UPPER TROUGH PUSHING INTO THE PACIFIC COAST
WHICH COULD EVENTUALLY MEAN SOUTHWEST FLOW ALOFT HERE IN NE MT.
THIS WOULD LEAD TO SOMEWHAT MORE UNSETTLED CONDITIONS THAN THAT
EXPECTED WITH A RIDGE PARKED OVER THE AREA. WILL BE LOOKING TO SEE
HOW MODELS HANDLE THE PROGRESSION OF THAT TROUGH IN THE VERY LATE
EXTENDED OVER THE COURSE OF THE NEXT SEVERAL DAYS. WAY DOWN THE
ROAD...THIS MAY PROVIDE THE CWA WITH THE NEXT MEANINGFUL CHANCE OF
UNSETTLED CONDITIONS. GIVEN THAT THIS IS 7 TO 10 DAYS OUT
THOUGH...THIS IS MERELY SPECULATION AT THIS POINT. ALTHOUGH THERE
ARE CONTRASTS THAT CAN BE MADE ABOUT THE OVERALL SHAPE AND SOME OF
THE SPATIAL AND TEMPORAL CHARACTERISTICS OF THE SYNOPTIC SCALE
PATTERN BY NEXT WEEKEND...IT IS QUITE INTERESTING TO SEE THE
SIMILARITIES IN BOTH THE ECMWF AND GFS SOLUTIONS EVEN THIS FAR OUT
IN THE FORECAST PERIOD. MALIAWCO
&&
.AVIATION...
DUE TO A LARGE RIDGE OVER MUCH OF THE U.S....VFR CONDITIONS WILL PREVAIL
AT THE TERMINAL LOCATIONS TODAY AND TONIGHT WITH ONLY A VERY
OUTSIDE CHANCE FOR AN AFTERNOON SHOWER. LIGHT AND VARIABLE WINDS EARLY
THIS MORNING WILL INCREASE FROM THE NORTHWEST BY THE AFTERNOON TO
BETWEEN 10 AND 15 KTS. MALIAWCO/MARTIN
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1145 AM EDT FRI JUN 28 2013
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL REMAIN OVER THE REGION THROUGH
THE WEEKEND. THIS SYSTEM WILL PRODUCE SHOWERS AND THUNDERSTORMS
THROUGH THE PERIOD WITH THE MOST WIDESPREAD COVERAGE OCCURRING
DURING THE DAYLIGHT HOURS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATED AT 1145 AM... SURFACE LOW PRESSURE DOWN TO 996 MB OVER
NORTHEAST NY MOVING NORTHEAST. MAIN CONCERN OVER THE NEXT SEVERAL
HOURS WILL BE FOR POTENTIAL FOR SHOWERS AND THUNDERSTORMS
PRODUCING ISOLATED FLASH FLOODING THIS AFTERNOON ALONG WITH A
SEVERE THREAT. SATELLITE LOOPS INDICATE THAT PARTIAL CLEARING IS
DEVELOPING ACROSS MUCH OF PA THIS MORNING WITH CLOUDY SKIES
CONTINUING ACROSS NY STATE. 12Z BUF SOUNDING SHOWS A BIT OF A WARM
LAYER AT 700 MB AND ANOTHER WEAK WARM LAYER UP AROUND 500 MB... SO
OVERALL MID-LEVEL LAPSE RATES ARE NOT STEEP. HOWEVER MID-LEVEL
WINDS ARE RATHER STRONG WITH 40 KTS SHOWN FROM 700 TO 500 MB. SFC
DEW POINTS REMAIN IN THE MID 60S WITH A WEAK SURFACE TROUGH MOVING
IN FROM THE WEST. KEY FOR STRONG THUNDERSTORM DEVELOPMENT THIS
AFTERNOON WILL BE AMOUNT OF SUNSHINE AND DESTABILIZATION THAT
MIGHT OCCUR.
LATEST 12Z NAM IS STILL NOT VERY IMPRESSED WITH THE INSTABILITY
INDICATING CAPES OF 500 J/KG OR LESS. HOWEVER THE LATEST RAP AND
LAST NIGHTS GFS SHOW MORE INSTABILITY WITH CAPES UP NEAR OR JUST
OVER 1000 J/KG FROM THE SOUTHERN TIER OF NY SOUTH INTO PA. GIVEN
THAT CLEARING IS ALREADY OCCURRING ACROSS MUCH OF PA SUSPECT THAT
CAPES PROBABLY WILL AT LEAST APPROACH 1000 J/KG ACROSS NE PA THIS
AFTERNOON... AND SOME STRONG THUNDERSTORMS WILL PROBABLY DEVELOP.
FARTHER NORTH CLEARING IS LESS CERTAIN SO EXPECTING SHOWERS WITH
ISOLATED THUNDER. GIVEN MODERATELY MOIST ATMOSPHERE ANY STORM
COULD PRODUCE A QUICK INCH OF RAIN WHICH WOULD BE ENOUGH TO CAUSE
ISOLATED FLASH FLOODING... SO AM PLANNING ON EXTENDING THE WATCH
INTO EARLY THIS EVENING. ISOLATED SEVERE STORMS ALSO APPEAR TO BE
POSSIBLE THIS AFTERNOON ESPECIALLY IN NORTHEAST PA WHERE HEATING
WILL INCREASE THE INSTABILTY. PREVIOUS DISCUSSION BELOW.
630 AM UPDATE...MODERATE TO HEAVY RAIN NOW CONFINED TO NORTHERN
ONEIDA COUNTY AND THIS WILL LIFT NORTH OF THE AREA BY 8 AM. NEXT
BATCH OF SHOWERS/THUNDERSTORMS ASSOCIATED WITH FRONT END OF UPPER
LEVEL LOW NOW MOVING INTO WESTERN NEW YORK. THIS WILL BEGIN
SPREADING ACROSS WRN PTN OF FA BY MID MORNING. ONLY MINOR
ADJUSTMENTS NEEDED TO POP GRIDS.
AT 445 AM...SFC LOW PRES WAS LIFTING NORTH THROUGH EASTERN NEW
YORK WITH LOCAL RADARS SHOWING MODERATE TO HEAVY RAINFALL ACROSS
THE WESTERN MOHAWK VALLEY AND THE NORTHERN SUSQUEHANNA REGION. THE
HEAVY PRECIP ON THE BACK SIDE OF THIS LOW WILL GRADUALLY LIFT
NORTH OF THE REGION BY MID MORNING. FLASH FLOOD WARNINGS ARE
CURRENTLY IN EFFECT FOR MUCH OF THIS AREA.
FOR TODAY, UPPER LEVEL LOW OVER THE NRN GREAT LAKES WILL DROP
SOUTHEAST INTO THE EASTERN LAKES. MID LEVEL SHORT WAVES ROTATING
AROUND THE FEATURE WILL GENERATE MORE WIDESPREAD SHOWERS AND
THUNDERSTORMS FROM LATE THIS MORNING THROUGH THE AFTERNOON.
ATMOSPHERE REMAINS VERY MOIST WITH PWATS AROUND 1.50-1.75 INCHES,
THEREFORE ANY CONVECTION WILL HAVE THE POTENTIAL FOR TORRENTIAL
DOWNPOURS. MODEL SOUNDINGS INDICATE CAPE VALUES OF 500-1000 J/KG
WHICH WILL ENHANCE CONVECTIVE ACTIVITY UNDER THE UPPER LEVEL
FEATURE. WILL CONTINUE WITH FLASH FLOOD WATCH THROUGH THIS
AFTERNOON DUE TO ADDITIONAL CONVECTIVE RAINFALL FALLING ON SATURATED
SOILS ESPECIALLY OVER CENTRAL NEW YORK EAST OF INTERSTATE 81 AND
NORTHEAST PENNSYLVANIA. THERE IS THE POTENTIAL THAT A FEW STORMS
COULD BECOME SEVERE BUT ONE AGAIN LAPSE RATES, CAPE VALUES AND MID
LEVEL WIND FIELDS ARE VERY MARGINAL. IF SVR CONVECTION DOES OCCUR
IT WOULD MOST LIKELY BE OVER THE SOUTHERN CATSKILLS AND POCONOS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
TONIGHT THROUGH SUNDAY NIGHT...H5 UPPER LEVEL TROF WILL REMAIN
JUST WEST OF FA THROUGH SUNDAY NIGHT WITH AIRMASS REMAINING
FAIRLY MOIST. CONVECTIVE ACTIVITY WILL PERSIST THROUGH THE PERIOD
WITH THE MOST WIDESPREAD ACTIVITY OCCURRING DURING THE DAYLIGHT
HOURS ENHANCED BY DIURNAL HEATING. AIRMASS BECOMES EVEN MORE
MOISTURE LADEN SUNDAY/SUNDAY NIGHT AS FULL LATITUDE UPPER LEVEL
TROF BEGINS TO TAP MORE GULF MOISTURE. A VERY WET PERIOD AHEAD
WITH THE CONTINUED POTENTIAL FOR LOCALIZED HEAVY RAINS.
MAX TEMPS WILL GENERALLY RANGE FROM THE MID 70S INTO THE LOW 80S.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
1 PM THU DISC... GLOBAL MODEL/WPC CONSENSUS CONTS TO SUGGEST QUITE AN
AMPLIFIED PATN FOR THIS TIME OF YEAR...WITH A SIG WRN
CONUS/CANADIAN RIDGE...AND ERN CONUS TROUGH. THIS LIKELY SPELLS A
WET PATN FOR NY/PA...WITH A SUSTAINED DEEP SRLY FLOW...AND LIKELY
S/WV IMPULSES RIDING NWD/NEWD UP THE FRONT SIDE OF THE
AFOREMENTIONED TROUGH AXIS. THUS...SCTD-NUMEROUS/LIKELY POPS WILL
BE RETAINED FOR MUCH OF THE PD.
ALTHOUGH MUGGY CONDS ARE FORESEEN...PERSISTENT PCPN SHOULD KEEP
HIGH TEMPS IN THE 70S-LWR 80S EACH DAY.
&&
.AVIATION /16Z FRIDAY THROUGH TUESDAY/...
700 AM EDT UPDATE...
ANOTHER CHALLENGING FORECAST IS IN STORE FOR TODAY. HEAVY RAIN
SHOWERS ARE CURRENTLY MOVING NE AWAY OF CENTRAL NY THIS MORNING AND
IFR CIGS HAVE SETTLED OVER THE REGION IN THE WAKE OF THE SHOWERS.
IFR CIGS SHOULD MIX OUT OVER THE NEXT COUPLE OF HOURS AND RETURN TO
VFR. THE NEXT ROUND OF SHOWERS ARE STARTING TO MOVE INTO CENTRAL
NY THIS MORNING. THESE SHOWERS ARE EXPECTED TO FILL IN AND BE
SCATTERED LIKE TODAY THROUGH THE AFTERNOON AND EARLY EVENING
HOURS. THIS ACTIVITY SHOULD MOVE OUT OF THE REGION BY 4Z TONIGHT.
THERE IS THE POSSIBILITY OF IFR CONDITIONS AGAIN FRIDAY NIGHT INTO
SATURDAY MORNING...HOWEVER CONFIDENCE IS LOW SO KEPT OUT OF TAFS
FOR THE TIME BEING.
OUTLOOK...SAT THROUGH TUE...
SAT THROUGH TUE... OCNL RESTRICTIONS ARE LIKELY EACH DAY...WITH
SHRA/TSRA IN THE VICINITY. THE MOST PERSISTENT RESTRICTIONS MAY
COME BY MON/MON NGT.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...FLASH FLOOD WATCH UNTIL 2 PM EDT THIS AFTERNOON FOR PAZ038>040-
043-044-047-048-072.
NY...FLASH FLOOD WATCH UNTIL 2 PM EDT THIS AFTERNOON FOR NYZ009-
015>018-022>025-036-037-044>046-055>057-062.
&&
$$
SYNOPSIS...RRM
NEAR TERM...MSE/RRM
SHORT TERM...RRM
LONG TERM...MLJ
AVIATION...KAH
AREA FORECAST DISCUSSION
NWS BUFFALO NY
955 AM EDT FRI JUN 28 2013
.SYNOPSIS...
LOW PRESSURE WILL SLOWLY LIFT ACROSS EASTERN NEW YORK TODAY...WITH
THIS SYSTEM EXPECTED TO STALL ACROSS THE REGION AS IT GRADUALLY WEAKENS
THROUGH THE WEEKEND. THIS WILL BRING PERIODS OF RAIN TODAY...WITH
EMBEDDED AREAS OF HEAVIER RAIN AND THUNDERSTORMS. THE THREAT FOR
SHOWERS AND PERHAPS A THUNDERSTORM WILL PERSIST THROUGH THE
WEEKEND...HOWEVER SHOWERS WILL BECOME INCREASINGLY MORE SCATTERED
AS THE WEEKEND WEARS ON.
&&
.NEAR TERM /THROUGH TONIGHT/...
FLOOD POTENTIAL CONTINUES ACROSS THE REGION TODAY.
THERE ARE TWO MAIN FEATURES TO WATCH TODAY...WITH THE MOST
OBVIOUS BEING THE LARGE AREA OF RAIN ASSOCIATED WITH THE WEAK
SURFACE LOW WHICH IS LIFTING ACROSS EASTERN NEW YORK STATE.
THROUGH DAYBREAK...RADAR SHOWS THE HEAVIEST RAIN TO THE EAST OF
OUR CWA. STEADY RAINS SHOULD BRING AROUND AN INCH TO LEWIS
COUNTY...WITH LESS TO THE WEST OF THIS. FLOOD POTENTIAL APPEARS TO
BE DIMINISHING EAST OF LAKE ONTARIO...HOWEVER UPSTREAM RAINS WILL
LIKELY CAUSE THE BLACK RIVER TO RISE AT BOONVILLE...PROBABLY
APPROACHING BUT FALLING JUST SHY OF FLOOD STAGE.
THE SECOND FEATURE IS A MORE SUBTLE UPPER LEVEL TROF AXIS WHICH
EXTENDS FROM WESTERN NEW YORK BACK INTO SOUTHERN ONTARIO TO
GEORGIAN BAY. SHOWERS ALONG THIS AXIS ARE FORECAST TO CONTINUE TO
EXPAND THIS MORNING BY THE HRRR. SEVERAL RUNS OF THE NAM/RGEM
SUPPORT THE HRRR FORECAST AND GIVEN ITS FAIRLY GOOD TRACK RECORD
FOR THIS EVENT AS WELL AS RADAR TRENDS...WE HAVE INCREASING
CONFIDENCE IN THE FORECAST. SHOWERS WITH EMBEDDED THUNDERSTORMS
SHOULD CONTINUE TO EXPAND ACROSS WESTERN NEW YORK THIS MORNING
THEN LIFT GRADUALLY NORTHEAST THIS AFTERNOON. THIS PRECIPITATION
WILL BE CONVECTIVE...WITH BUFKIT SHOWING A MOIST SOUNDING WITH
THIN AND NARROW CAPES...AND P-WAT VALUES AROUND 1.6 INCHES.
CONSENSUS QPFS FROM THE HIGHER RESOLUTION MODELS INCLUDING RECENT
RUNS OF THE NAM/RGEM/SREF ONLY AVERAGE AROUND AN INCH WITH THIS.
HOWEVER...GIVEN THE SLOW MOTION OF THE CONVECTIVE CELLS...LOCALLY
HIGHER AMOUNTS ARE POSSIBLE. RAIN AMOUNTS IN EXCESS OF TWO INCHES
WOULD BE A CONCERN PRETTY MUCH ANYWHERE...WITH URBAN AREAS...THE
BUFFALO CREEKS...AND AREAS WITH RECENT RAINS VULNERABLE TO LESSER
RAINFALL AMOUNTS. FOLLOWING THIS...WILL MAINTAIN THE FLOOD
WATCH...WITH A KEEN FOCUS ON SHOWERS DEVELOPING ACROSS SOUTHERN
ONTARIO AND EASTERN LAKE ERIE.
THE UPPER LOW WILL GRADUALLY MOVE ACROSS THE REGION TONIGHT...WHICH
WILL EFFECTIVELY END THIS AXIS OF FOCUS AS THE LOW BECOMES
VERTICALLY STACKED. THERE WILL BE A LINGERING THREAT FOR SHOWERS
TONIGHT...WITH SHOWERS EXPECTED TO BECOME INCREASINGLY SCATTERED
IN NATURE AS THE NIGHT GOES ON. WHILE WIDESPREAD THUNDERSTORMS ARE
NOT LIKELY...THERE MAY BE SOME EMBEDDED IN AREAS OF HEAVY RAIN
TODAY AND INTO THIS EVENING.
TEMPERATURES WILL NOT RISE VERY MUCH AT ALL TODAY...WITH PERSISTENT
CLOUDS COVER AND AREAS OF SHOWERS. EXPECT HIGHS TO ONLY BE AROUND 70
DEGREES IN MOST LOCATIONS. OVERNIGHT LOWS SHOULD DROP INTO THE UPPER
50S TO LOWER 60S. PATCHY FOG IS LIKELY...AND WHILE MOSTLY CLOUDY
SKIES ARE EXPECTED...ANY CLEARING WOULD QUICKLY FAIRLY DENSE FOG
DEVELOPMENT.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
A FULL LATITUDE TROUGH IS FORECAST TO REMAIN IN PLACE FROM SOUTHERN
QUEBEC TO THE TENNESSEE VALLEY THROUGH THIS PERIOD. THE DEEP LAYERED
SOUTHERLY FLOW WILL KEEP MOIST AND SOMEWHAT UNSTABLE AIR OVER OUR
AREA WHICH WILL LEAD TO OCCASIONAL SHOWERS AND SCATTERED
THUNDERSTORMS. THE MODELS AGREE THAT A LOW LEVEL TROUGH/BAROCLINIC
ZONE WILL REMAIN STALLED OVER CENTRAL NEW YORK STATE. THIS
BOUNDARY WILL HELP TO FOCUS THE MOISTURE WHICH COULD LEAD TO
ENHANCED RAINFALL AT TIMES. IN ADDITION...A SERIES OF SHORT WAVES
WILL BE LIFTING NORTH THROUGH THE EASTERN FLANK OF THE UPPER LEVEL
TROUGH...BUT THE TIMING OF THESE IMPULSES CANNOT BE PINNED DOWN AT
THIS TIME. AS A RESULT...WILL FOLLOW THE PREVIOUS TREND OF
INDICATING HIGHER POPS DURING THE AFTERNOON WHEN DAYTIME HEATING
WILL LEAD TO A BETTER CHANCE FOR A FEW THUNDERSTORMS. ALL OF THESE
FACTORS COULD LEAD TO A POTENTIAL FOR MORE FLOODING
ISSUES...ESPECIALLY WITH THE ANTECEDENT MOISTURE THAT WILL BE IN
PLACE FROM PREVIOUS RAINFALL.
ABUNDANT CLOUD COVER AND SHOWER ACTIVITY ALONG WITH SLIGHTLY COOLER
AIR ALOFT DUE TO THE PRESENCE OF THE UPPER LEVEL TROUGH WILL HELP
KEEP TEMPERATURES SLIGHTLY BELOW AVERAGE DURING THIS PERIOD.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
A DEEP UPPER LEVEL TROUGH EXTENDING FROM JAMES BAY ACROSS THE GREAT
LAKES DOWN TO THE CENTRAL GULF COAST WILL GRADUALLY RETROGRADE WEST
TO THE MISSISSIPPI VALLEY AS THE BERMUDA HIGH REASSERTS IT/S
DOMINANCE OVER THE WESTERN ATLANTIC. THE PRESENCE OF A DEEP LAYERED
SOUTHERLY FLOW AND AN ABUNDANT SUPPLY OF LOW LEVEL MOISTURE
WILL KEEP WESTERN AND NORTH CENTRAL NEW YORK IN A FAVORABLE POSITION
FOR UNSETTLED WEATHER THROUGH MUCH OF THE UPCOMING WEEK. THE BULK OF
PRECIPITATION WILL BE IN THE FORM OF DIURNALLY DRIVEN CONVECTION
WITH SHOWERS AND THUNDERSTORMS BREAKING OUT IN THE AFTERNOON AND
EVENING HOURS EACH DAY.
TEMPERATURES DURING THE PERIOD WILL SHOW A SLOW MODERATING TREND AS
THE UPPER LEVEL TROUGH SLIDES WEST AND SOMEWHAT WARMER AIR OVER THE
EAST COAST PUSHES BACK INTO THE LOWER GREAT LAKES.
&&
.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
MAINLY IFR CONDITIONS PERSIST ACROSS THE REGION THIS MORNING WITH
LOW CIGS AND VSBYS IN A VERY MOIST ATMOSPHERE.
ACROSS THE EAST...A STEADY AREA OF RAIN OVER THE NORTH COUNTRY
WILL SLOWLY LIFT NORTH ALLOWING FOR A SLOW IMPROVEMENT IN CONDS AT KART.
ELSEWHERE...SHOWERS WITH EMBEDDED THUNDERSTORMS SHOULD EXPAND
RESULTING IN VARIABLE CONDITIONS...OCCASIONALLY IFR OR LESS IN
HEAVIER RAINS.
SHOWERS SHOULD BE VERY SLOW MOVING. ALTHOUGH SHOWERS SHOULD TAPER
OFF LATER TONIGHT...SIGNIFICANT LOW MOISTURE...AND LESS MOISTURE
ALOFT WILL LIKELY LEAD TO FAIRLY WIDESPREAD IFR OR LOWER
CONDITIONS. ANY CLEARING ALOFT WOULD LIKELY RESULT IN SOME FAIRLY
DENSE GROUND FOG.
OUTLOOK...
SATURDAY THROUGH TUESDAY...MAINLY VFR WITH A CHANCE OF MAINLY
AFTERNOON SHOWERS AND THUNDERSTORMS WITH ASSOCIATED BRIEF MVFR/IFR.
&&
.MARINE...
LOW PRESSURE TRACKING ACROSS NEW YORK STATE WILL CAUSE NNE WINDS TO
PICK UP THIS MORNING. CONDITIONS WILL BECOME A BIT CHOPPY...BUT
WAVES ARE EXPECTED TO REMAIN BELOW SCA CRITERIA. AFTER THIS WINDS
WILL DIMINISH...WITH NO HEADLINES ANTICIPATED FOR THIS WEEKEND.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR NYZ006>008.
FLOOD WATCH THROUGH THIS EVENING FOR NYZ001>005-010>014-
019>021-085.
MARINE...NONE.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL/LEVAN
SHORT TERM...TJP
LONG TERM...TJP/WOOD
AVIATION...APFFEL/LEVAN
MARINE...APFFEL/TJP
AREA FORECAST DISCUSSION
NWS BUFFALO NY
715 AM EDT FRI JUN 28 2013
.SYNOPSIS...
LOW PRESSURE WILL SLOWLY LIFT ACROSS EASTERN NEW YORK TODAY...WITH
THIS SYSTEM EXPECTED TO STALL ACROSS THE REGION AS IT GRADUALLY WEAKENS
THROUGH THE WEEKEND. THIS WILL BRING PERIODS OF RAIN TODAY...WITH
EMBEDDED AREAS OF HEAVIER RAIN AND THUNDERSTORMS. THE THREAT FOR
SHOWERS AND PERHAPS A THUNDERSTORM WILL PERSIST THROUGH THE
WEEKEND...HOWEVER SHOWERS WILL BECOME INCREASINGLY SCATTERED AS
THE WEEKEND WEARS ON.
&&
.NEAR TERM /THROUGH TONIGHT/...
THERE CONTINUES TO BE A POTENTIAL FOR FLOODING ACROSS PORTIONS OF
WESTERN NEW YORK TODAY. THERE APPEARS TO BE TWO MAIN FEATURES TO
WATCH TODAY...WITH THE MOST OBVIOUS BEING THE LARGE AREA OF RAIN
ASSOCIATED WITH THE WEAK SURFACE LOW WHICH IS LIFTING ACROSS EASTERN
NEW YORK STATE. THROUGH DAYBREAK...RADAR SHOWS THE HEAVIEST RAIN
TO THE EAST OF OUR CWA. STEADY RAINS SHOULD BRING AROUND AN INCH
TO LEWIS COUNTY...WITH LESS TO THE WEST OF THIS. FLOOD POTENTIAL
APPEARS TO BE DIMINISHING EAST OF LAKE ONTARIO...HOWEVER UPSTREAM
RAINS WILL LIKELY CAUSE THE BLACK RIVER TO RISE AT BOONVILLE...PROBABLY
APPROACHING BUT FALLING JUST SHY OF FLOOD STAGE.
THE SECOND FEATURE WE WILL BE KEEPING A CLOSE EYE ON IS A MORE
SUBTLE UPPER LEVEL TROF AXIS WHICH EXTENDS FROM WESTERN NEW YORK
BACK INTO SOUTHERN ONTARIO TO GEORGIAN BAY. SHOWERS ALONG THIS
AXIS ARE FORECAST TO CONTINUE TO EXPAND THIS MORNING BY THE HRRR.
SEVERAL RUNS OF THE NAM/RGEM SUPPORT THE HRRR FORECAST AND GIVEN
ITS FAIRLY GOOD TRACK RECORD FOR THIS EVENT AS WELL AS RADAR
TRENDS...WE HAVE INCREASING CONFIDENCE IN THE FORECAST. SHOWERS
WITH EMBEDDED THUNDERSTORMS SHOULD CONTINUE TO EXPAND ACROSS
WESTERN NEW YORK THIS MORNING THEN LIFT GRADUALLY NORTHEAST THIS
AFTERNOON. THIS PRECIPITATION WILL BE CONVECTIVE...WITH BUFKIT
SHOWING A MOIST SOUNDING WITH THIN AND NARROW CAPES...AND P-WAT
VALUES AROUND 1.6 INCHES. CONSENSUS QPFS FROM THE HIGHER
RESOLUTION MODELS INCLUDING RECENT RUNS OF THE NAM/RGEM/SREF ONLY
AVERAGE AROUND AN INCH WITH THIS. HOWEVER...GIVEN THE SLOW MOTION
OF THE CONVECTIVE CELLS...LOCALLY HIGHER AMOUNTS ARE POSSIBLE.
RAIN AMOUNTS IN EXCESS OF TWO INCHES WOULD BE A CONCERN PRETTY
MUCH ANYWHERE...WITH URBAN AREAS...THE BUFFALO CREEKS...AND AREAS
WITH RECENT RAINS VULNERABLE TO LESSER RAINFALL AMOUNTS. FOLLOWING
THIS...WILL MAINTAIN THE FLOOD WATCH...WITH A KEEN FOCUS ON
SHOWERS DEVELOPING ACROSS SOUTHERN ONTARIO AND EASTERN LAKE ERIE.
THE UPPER LOW WILL GRADUALLY MOVE ACROSS THE REGION TONIGHT...WHICH
WILL EFFECTIVELY END THIS AXIS OF FOCUS AS THE LOW BECOMES
VERTICALLY STACKED. THERE WILL BE A LINGERING THREAT FOR SHOWERS
TONIGHT...WITH SHOWERS EXPECTED TO BECOME INCREASINGLY SCATTERED
IN NATURE AS THE NIGHT GOES ON. WHILE WIDESPREAD THUNDERSTORMS ARE
NOT LIKELY...THERE MAY BE SOME EMBEDDED IN AREAS OF HEAVY RAIN
TODAY AND INTO THIS EVENING.
TEMPERATURES WILL NOT RISE VERY MUCH AT ALL TODAY...WITH PERSISTENT
CLOUDS COVER AND AREAS OF SHOWERS. EXPECT HIGHS TO ONLY BE AROUND 70
DEGREES IN MOST LOCATIONS. OVERNIGHT LOWS SHOULD DROP INTO THE UPPER
50S TO LOWER 60S. PATCHY FOG IS LIKELY...AND WHILE MOSTLY CLOUDY
SKIES ARE EXPECTED...ANY CLEARING WOULD QUICKLY FAIRLY DENSE FOG
DEVELOPMENT.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
A FULL LATITUDE TROUGH IS FORECAST TO REMAIN IN PLACE FROM SOUTHERN
QUEBEC TO THE TENNESSEE VALLEY THROUGH THIS PERIOD. THE DEEP LAYERED
SOUTHERLY FLOW WILL KEEP MOIST AND SOMEWHAT UNSTABLE AIR OVER OUR
AREA WHICH WILL LEAD TO OCCASIONAL SHOWERS AND SCATTERED
THUNDERSTORMS. THE MODELS AGREE THAT A LOW LEVEL TROUGH/BAROCLINIC
ZONE WILL REMAIN STALLED OVER CENTRAL NEW YORK STATE. THIS
BOUNDARY WILL HELP TO FOCUS THE MOISTURE WHICH COULD LEAD TO
ENHANCED RAINFALL AT TIMES. IN ADDITION...A SERIES OF SHORT WAVES
WILL BE LIFTING NORTH THROUGH THE EASTERN FLANK OF THE UPPER LEVEL
TROUGH...BUT THE TIMING OF THESE IMPULSES CANNOT BE PINNED DOWN AT
THIS TIME. AS A RESULT...WILL FOLLOW THE PREVIOUS TREND OF
INDICATING HIGHER POPS DURING THE AFTERNOON WHEN DAYTIME HEATING
WILL LEAD TO A BETTER CHANCE FOR A FEW THUNDERSTORMS. ALL OF THESE
FACTORS COULD LEAD TO A POTENTIAL FOR MORE FLOODING
ISSUES...ESPECIALLY WITH THE ANTECEDENT MOISTURE THAT WILL BE IN
PLACE FROM PREVIOUS RAINFALL.
ABUNDANT CLOUD COVER AND SHOWER ACTIVITY ALONG WITH SLIGHTLY COOLER
AIR ALOFT DUE TO THE PRESENCE OF THE UPPER LEVEL TROUGH WILL HELP
KEEP TEMPERATURES SLIGHTLY BELOW AVERAGE DURING THIS PERIOD.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
A DEEP UPPER LEVEL TROUGH EXTENDING FROM JAMES BAY ACROSS THE GREAT
LAKES DOWN TO THE CENTRAL GULF COAST WILL GRADUALLY RETROGRADE WEST
TO THE MISSISSIPPI VALLEY AS THE BERMUDA HIGH REASSERTS IT/S
DOMINANCE OVER THE WESTERN ATLANTIC. THE PRESENCE OF A DEEP LAYERED
SOUTHERLY FLOW AND AN ABUNDANT SUPPLY OF LOW LEVEL MOISTURE
WILL KEEP WESTERN AND NORTH CENTRAL NEW YORK IN A FAVORABLE POSITION
FOR UNSETTLED WEATHER THROUGH MUCH OF THE UPCOMING WEEK. THE BULK OF
PRECIPITATION WILL BE IN THE FORM OF DIURNALLY DRIVEN CONVECTION
WITH SHOWERS AND THUNDERSTORMS BREAKING OUT IN THE AFTERNOON AND
EVENING HOURS EACH DAY.
TEMPERATURES DURING THE PERIOD WILL SHOW A SLOW MODERATING TREND AS
THE UPPER LEVEL TROUGH SLIDES WEST AND SOMEWHAT WARMER AIR OVER THE
EAST COAST PUSHES BACK INTO THE LOWER GREAT LAKES.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
FOR THE 12Z TAF CYCLE...EXPECT A MIX OF CONDITIONS EARLY THIS
MORNING...MAINLY IN THE IFR CATEGORY. THIS WILL BE THE RESULT OF
LOW LEVEL MOISTURE AND SHOWERS. A STEADY AREA OF RAIN EAST OF LAKE
ONTARIO WILL LIFT NORTHWARD THIS MORNING...ALLOWING CONDITIONS AT
ART TO IMPROVE. ELSEWHERE...SHOWERS WITH EMBEDDED THUNDERSTORMS
SHOULD EXPAND RESULTING IN VARIABLE CONDITIONS...OCCASIONALLY IFR
OR LESS IN HEAVIER RAINS.
SHOWERS SHOULD BE VERY SLOW MOVING...LIKELY TO DRIFT
NORTHEASTWARD THIS AFTERNOON BEFORE WEAKENING TONIGHT. ALTHOUGH
SHOWERS SHOULD TAPER OFF LATER TONIGHT...SIGNIFICANT LOW
MOISTURE...AND LESS MOISTURE ALOFT WILL LIKELY LEAD TO FAIRLY
WIDESPREAD IFR OR LOWER CONDITIONS. ANY CLEARING ALOFT WOULD LIKELY
RESULT IN SOME FAIRLY DENSE GROUND FOG.
OUTLOOK...
SATURDAY THROUGH TUESDAY...MAINLY VFR WITH A CHANCE OF MAINLY
AFTERNOON SHOWERS AND THUNDERSTORMS WITH ASSOCIATED BRIEF MVFR/IFR.
&&
.MARINE...
LOW PRESSURE TRACKING ACROSS NEW YORK STATE WILL CAUSE NNE WINDS TO
PICK UP THIS MORNING. CONDITIONS WILL BECOME A BIT CHOPPY...BUT
WAVES ARE EXPECTED TO REMAIN BELOW SCA CRITERIA. AFTER THIS WINDS
WILL DIMINISH...WITH NO HEADLINES ANTICIPATED FOR THIS WEEKEND.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...FLOOD WATCH THROUGH THIS EVENING FOR NYZ006>008.
FLOOD WATCH THROUGH THIS EVENING FOR NYZ001>005-010>014-
019>021-085.
MARINE...NONE.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL
SHORT TERM...TJP
LONG TERM...TJP/WOOD
AVIATION...APFFEL
MARINE...APFFEL/TJP
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1040 AM EDT FRI JUN 28 2013
.SYNOPSIS...
A WARM AND HUMID AIR MASS COMBINED WITH A PERSISTENT TROUGH OF LOW
PRESSURE OVER THE REGION WILL RESULT IN A GOOD CHANCE OF SHOWERS AND
THUNDERSTORMS EACH DAY THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1040 AM FRIDAY...
LITTLE DOUBT THAT MOST OF THE AREA WILL SEE SHOWERS/STORMS SOMETIME
IN THE NEXT 18 HOURS... ALTHOUGH IT LOOKS LIKE WE MAY SEE A SLIGHT
DELAY IN THE MORE ORGANIZED CONVECTION UNTIL LATER IN THE DAY.
ACCORDING TO CURRENT MESOANALYSES WE ARE SLOWLY DESTABILIZING BUT
WITH A LOT OF REMAINING CINH. LATEST SATELLITE IMAGERY SHOWS THAT
MUCH OF THE MORNING STRATUS IN THE COASTAL PLAIN IS SLOWLY MOVING
OUT TO THE EAST... WHILE THE WRN SECTIONS ARE SEEING HIGH THIN
CLOUDS ASSOCIATED WITH THE NOW-DYING MCS DIVING FROM MEMPHIS INTO
MS/AL. OVERNIGHT RUNS OF THE RAP MODEL HAVE HAD A DIFFICULT TIME
WITH THE MCV TO OUR WEST... TRACKING IT EASTWARD THROUGH THE
CAROLINAS WHEN TRAJECTORIES AND OBSERVATIONS SUGGEST THAT IT WILL
TAKE A MORE SRN ROUTE THROUGH AL AND PERHAPS GA. WITH THIS FEATURE
LIKELY SLIDING TO OUR SOUTH... WHILE ANOTHER AREA OF ENHANCED
MID/HIGH-LEVEL FORCING FOR ASCENT TRACKS UP THROUGH PA... NC COULD
BE LEFT BENEATH A RELATIVE MINIMUM IN TERMS OF LARGE SCALE DYNAMIC
FORCING. THAT SAID... DEEP LAYER SHEAR IS EXPECTED TO STEADILY
INCREASE THROUGH THE DAY -- ESPECIALLY INTO THE EVENING -- AND WITH
THE DEARTH OF MORNING CLOUD COVER LEADING TO GOOD HEATING (TEMPS ARE
RUNNING A FEW DEGREES COOLER THAN YESTERDAY IN THE SOUTHEAST BUT 1-7
DEGREES WARMER THAN THIS TIME THURSDAY OVER THE REST OF CENTRAL NC)
AND MODELS PROJECTING 1500-2500 J/KG OF MLCAPE OVER ALL BUT THE NW
CWA BY MID AFTERNOON... SEE NO REASON TO THINK THAT WE WON`T SEE
INCREASING STORMS (IN NUMBER AND INTENSITY) HEADING THROUGH THE
MID-LATE AFTERNOON AND THROUGH THE EVENING. THE LATEST HRRR RUN
DEPICTS THIS SCENARIO QUITE WELL... BRINGING SCATTERED STORMS INTO
THE TRIAD TOWARD 19-20Z THEN CONGEALING INTO AN ORGANIZED BAND OF
STORM CLUSTERS HEADING EASTWARD THROUGH 04Z. STILL APPEARS THAT
SEVERE WIND GUSTS WILL BE THE BIGGEST THREAT LATE TODAY INTO TONIGHT
GIVEN THAT WE HAVE SOME DRY AIR NOT FAR OFF THE SURFACE. THE -10C TO
-30C CAPE IS QUITE LOW THIS MORNING AND DON`T EXPECT THAT TO CHANGE
MUCH WITH ONLY MINIMAL COOLING ALOFT AND NO APPARENT OPPORTUNITY FOR
GOOD MOISTURE FLUX IN THIS MIXED PHASE REGION... THUS THE RISK OF
LARGE HAIL SHOULD BE SECONDARY. IT IS INTERESTING HOW VERY DRY THE
12Z GSO SOUNDING WAS... WITH A PW OF 1.02 INCHES... MUCH LOWER THAN
IN PAST DAYS AND A BIT OF AN OUTLIER COMPARED TO SURROUNDING UPPER
AIR PLOTS. IT ALSO DEPARTS QUITE A BIT FROM THE PW NOTED ON TPW
BLENDED IMAGERY (AROUND 1.4 INCHES IN THE TRIAD). MODELS DO SHOW A
REMOISTENING OF THE COLUMN HERE THIS AFTERNOON... TOUGH TO BELIEVE
CONSIDERING THE OBSERVED UPPER-AIR DATA UPSTREAM THIS MORNING AND
THE LOW DEW POINTS IN THE TRIAD. WILL LEAVE IN GOOD CHANCE POPS HERE
FOR NOW GIVEN THE IMPROVING BULK SHEAR THROUGH THE DAY... ALTHOUGH
WE SHOULD SEE A RELATIVE MINIMUM IN COVERAGE IN THE TRIAD. LITTLE
CHANGE IN HIGHS WITH TEMP TRENDS SUPPORTING READINGS OF 89-94. WILL
CONTINUE TO TREND POPS DOWN AND OUT WEST TO EAST ESPECIALLY AFTER
MIDNIGHT WITH LOSS OF HEATING. FOG/STRATUS HAS BEEN TOUGH TO
FORECAST THE LAST FEW DAYS BUT WILL LEAN TOWARD PERSISTENCE... WITH
BETTER COVERAGE EAST OF HIGHWAY 1 WITHIN A VERY LIGHT SW FLOW. -GIH
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
AS OF 300 AM FRIDAY...
AS THE UPPER TROUGH CONTINUES TO DEEPEN...MID TO UPPER LEVEL FLOW
WILL BECOME SWLY AND WE WILL HAVE TO BE CONCERN WITH SHORTWAVE
IMPULSES FROM THE SW AS OPPOSE TO THE W-NW FROM RECENT DAYS. ANOTHER
IMPORTANT DIFFERENCE TO NOTE IS HOW MODELS ARE HANDLING THE
MEANDERING SURFACE TROUGH/FRONT WITH BOTH THE NAM AND GFS ADVECTING
CONSIDERABLY LOWER THETA-E AIR INTO THE LOW-LEVELS...WHICH
EFFECTIVELY LESSENS CAPE OVER THE WESTERN PIEDMONT. THIS WOULD
POTENTIALLY CONFINE THE BEST CONVECTIVE ACTIVITY TO EASTERN NC WITH
LOWER PRECIP PROBABILITIES THAN CURRENTLY FORECASTING ACROSS THE
WESTERN AND POSSIBLY CENTRAL PIEDMONT.
FOR STORMS THAT DO DEVELOP...THE MODEST MID-LEVEL WIND FIELD
OF 30 TO 35KTS AND STRONG DESTABILIZATION WITH 2000 TO 2500
J/KG OF MLCAPE WILL ONCE AGAIN SUPPORT THE THREAT FOR DAMAGING WING
GUSTS AND HAIL. ADDITIONALLY WITH THE UPPER FLOW NOW PARALLEL TO THE
WEAK SURFACE BOUNDARY...EASTERN AREAS WE WILL HAVE TO BE ON THE
ALERT FOR FOR TRAINING OF STORMS AND THE INHERENT HEAVY RAIN AND
FLOODING THREAT.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 300 AM FRIDAY...
AN UNUSUALLY AMPLIFIED UPPER LEVEL PATTERN WILL PERSIST THROUGH MUCH
OF THE PERIOD AS RIDGES DOMINATE WEST OF THE ROCKIES (EXTENDING UP
INTO CANADA) AND ACROSS THE WESTERN ATLANTIC...WITH A DEEP TROUGH
SANDWICHED IN THE MIDDLE. THIS TROUGH WILL GRADUALLY RETROGRADE
THROUGH THE PERIOD...NEVERTHELESS LEAVING CENTRAL NC WITHIN A
PERSISTENT DEEP SOUTHWESTERLY FLOW. AS A RESULT...NUMEROUS
DISTURBANCES ALOFT WILL MOVE ACROSS THE AREA AND WITH MOISTURE
REMAINING HIGH (BETWEEN 1.75-2 INCHES)...UNSETTLED WEATHER WILL
CONTINUE THROUGH THE ENTIRE LONG TERM PERIOD (IF NOT LONGER)...WITH
ABOVE NORMAL CHANCES OF SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS EXPECTED EACH DAY (MOSTLY DIURNALLY DRIVEN). AS THE
UPPER LEVEL TROUGH RETROGRADES...THE RIDGE OVER THE WESTERN ATLANTIC
WILL PUSH WESTWARD...THEREFORE EVENTUALLY EXERTING SOME MORE
INFLUENCE OVER THE REGION BY THE MIDDLE/LATTER PORTION OF THE WEEK.
THIS IS WHEN WE MAY START SEEING A DECREASE IN PRECIP COVERAGE...
ESPECIALLY OVER EASTERN NC.
OTHERWISE...WITH THE INCREASED FLOW ALOFT...DECENT DEEP LAYER SHEAR
WILL PERSIST OVER THE AREA AND THEREFORE WE SHOULD SEE MORE IN THE
WAY OF ORGANIZED CONVECTION. THIS MAY RESULT IN SOME STRONG TO
SEVERE STORMS. ANOTHER SIGNIFICANT WEATHER THREAT WILL BE THE
INCREASING FLOODING RISK AS THE AREA REMAINS IN THIS EXTENDED WET
PATTERN. DAYTIME HIGHS WILL GENERALLY BE BELOW NORMAL THROUGH THE
PERIOD...WITH MOSTLY MID 80S EXPECTED. OVERNIGHT LOWS WILL MOSTLY BE
IN THE LOWER 70S.
&&
.AVIATION /11Z THURSDAY THROUGH TUESDAY/...
AS OF 640 AM FRIDAY...
PATCHY IFR OT MVFR STRATUS AND OR FOG SHOULD LIFT BY 13-14Z THIS
MORNING... WITH PREDOMINATELY VFR CONDITIONS INTO THE EARLY
AFTERNOON BEFORE ANOTHER ROUND OF SCATTERED TO NUMEROUS STORMS ARE
EXPECTED OVER CENTRAL NC.
LOOKING BEYOND FRIDAY...THE WEATHER PATTERN WILL CHANGE VERY LITTLE
THE NEXT SEVERAL DAYS. AN UNSEASONABLY STRONG LOW PRESSURE TROUGH
COMBINED WITH A WARM AND UNSTABLE AIR WILL RESULT IN SCATTER TO
NUMEROUS SHOWERS AND STORMS EACH AFTERNOON/EARLY EVENING... AND
THE POTENTIAL FOR STRATUS OR FOG EACH MORNING.
&&
.EQUIPMENT...
KRAX WSR-88D WILL REMAIN DOWN OR IN DEGRADED MODE THROUGH THIS
MORNING. KRAX HAS BEEN IN A SEVERELY DEGRADED MODE FOR SEVERAL
DAYS... AND THE NEEDED REPAIRS WERE DEEMED TO BE CRITICAL. THE TEAM
OF TECHNICIANS WILL MAKE THESE REPAIRS AS QUICKLY AS POSSIBLE... AND
IS WORKING TO RETURN THE RADAR TO NORMAL SERVICE BY EARLY THIS
AFTERNOON. WE APOLOGIZE FOR THE INCONVENIENCE. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...CBL
LONG TERM...KRR
AVIATION...CBL
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
946 AM CDT FRI JUN 28 2013
.UPDATE...
ISSUED AT 945 AM CDT FRI JUN 28 2013
THE MAIN CHANGES FOR THE MORNING UPDATE WILL BE TO INCREASE WINDS
A BIT AND LOWER POPS SLIGHTLY THIS AFTERNOON. THERE WILL BE ABOUT
35KT TO MIX EFFICIENTLY BY AFTERNOON...AND WE WILL BE CLOSE TO
WIND ADVISORY CRITERIA WITH GUSTS OVER 35MPH POSSIBLE. FOR NOW
WILL HOLD ON AN ADVISORY...AND MONITOR POTENTIAL FOR 1PM UPDATE.
WE WILL ALSO LOWER POPS A BIT THIS AFTERNOON WITH MORE ISOLATED
(WEST) TO SCATTERED (EAST) COVERAGE OF SHOWERS AND A FEW STORMS
EXPECTED. CAPES RISE AROUND 1000 J/KG BY AFTERNOON WITH CYCLONIC
FLOW AND A JET STREAK. TEMPS MAY ALSO BE SLIGHTLY COOLER IN ALL
BUT THE FAR WEST AND WILL LOWER A FEW DEGREES WITH CLOUDS EAST AND
LOWER CONVECTIVE TEMPS TODAY.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 350 AM CDT FRI JUN 28 2013
CHALLENGES INCLUDE CLOUD COVER/PRECIPITATION CHANCES TODAY AND
THEN TEMPERATURES THROUGH THE PERIOD. GFS/NAM/ECMWF/GEM ARE IN
GOOD AGREEMENT...BUT WILL LEAN ON LATEST RAP GUIDANCE FOR NEAR TERM
FORECAST.
FOR TODAY...STRATOCUMULUS DECK ACROSS NORTH-CENTRAL MN WILL EXPAND
SOUTH AND WEST THROUGH THE DAY GIVEN CONVECTIVE TEMPERATURES IN
THE UPPER 60S TO MID 70S. WITH A 100 KT 300 HPA JET STREAK MOVING
THROUGH NORTHWEST FLOW ALOFT AND 500 TO 1000 J/KG OF MLCAPE...
SOME OF THESE THERMAL CU MAY GIVE WAY TO SCATTERED AFTERNOON
SHOWERS AND THUNDERSTORMS. REMOVED POPS ALONG AND WEST OF THE
VALLEY THIS MORNING WITH A MOSTLY SUNNY START TO THE DAY...BUT
WILL EXPAND CHANCE POPS SOUTH AND WEST WITH INCREASING CLOUD COVER
THIS AFTERNOON. BOUNDARY LAYER IS 3 TO 6 C COLDER THAN YESTERDAY...
SO EXPECT DAYTIME HIGHS IN THE 70S. WITH 20 TO 30 KTS AT 850 HPA
TO MIX TO THE SURFACE...EXPECT ANOTHER BREEZY AFTERNOON WITH WINDS
FROM 15 TO 20 MPH AND OCCASIONAL GUSTS UP TO 30 MPH.
THERMAL CU WILL DISSIPATE AFTER SUNSET...BUT EXPECT SOME THICKER
CLOUD COVER TO TAKE ITS TIME MOVING OUT OF THE REGION OVERNIGHT.
WINDS WILL SUBSIDE WITH SURFACE HIGH PRESSURE BUILDING ACROSS THE
REGION. OVERNIGHT LOWS WILL BE IN THE 50S.
MOST OF SATURDAY WILL BE DRY...BUT DID KEEP 20 POPS REGION-WIDE
THROUGH THE DAY AS OPERATIONAL MODELS PAINT SEEMINGLY RANDOM LIGHT
QPF IN ASSOCIATION WITH A WEAK SHORT-WAVE ALOFT. SURFACE TO MID-
LEVEL FORCING IS WEAK...SO EXPECT MINIMAL ACCUMULATION WITH ANY
SHOWERS THAT DO DEVELOP. ANOTHER COOLER DAY WITH HIGHS AGAIN IN
THE 70S.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 350 AM CDT FRI JUN 28 2013
SURFACE PRESSURE RIDGE WILL SLIDE SLOWLY ACROSS THE NORTHERN
PLAINS SUNDAY AND MONDAY RESULTING IN DRY...MOSTLY SUNNY
CONDITIONS. WINDS WILL BE LIGHT AND TEMPERATURES WILL BE NEAR
SEASONAL NORMALS WITH HIGHS IN THE UPPER 70S TO LOWER 80S.
A BLEND OF THE GFS/ECMWF TO BE FOLLOWED EARLY IN THE EXTENDED THEN
TRENDING TOWARD THE GFS IN DAYS 5-7. THE UPPER PATTERN AMPLIFIES
DURING THE PERIOD WITH RIDGING OVER THE WRN CONUS AND TROF OVER THE
ERN THIRD OF THE COUNTRY. THE RIDGING OUT WEST WILL RETROGRADE
SOMEWHAT WEST ALLOWING FOR PIECES OF S/WV ENERGY TO SLIDE DOWN THE
BACK SIDE OF THE TROF BY TUE/TUE NIGHT. A FRONTAL BOUNDARY ACROSS
THE REGION WILL HELP FOCUS PRECIPITATION TUE-THU WITH WED BEING THE
MOST OPTIMAL PERIOD FOR SCATTERED SHRA/TSRA. THE BOUNDARY IS
EXPECTED TO WEAKEN BY THU. TEMPERATURES WILL BE TEMPERED WITH HIGHS
IN THE UPPER 70S TO AROUND 80 THROUGH THE WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 704 AM CDT FRI JUN 28 2013
WESTERN EDGE OF MVFR/IFR CLOUD DECK EXTENDS ALONG A KHCO-KMAH-
KPKD LINE AND WILL CONTINUE TO SLIDE SOUTH AND WEST AROUND 10 KTS.
CEILINGS SHOULD LIFT TO VFR CONDITIONS BY THIS AFTERNOON. CLEAR
SKIES AT KGFK/KFAR/KDVL THIS MORNING WILL FILL-IN WITH THERMAL CU
THROUGHOUT THE DAY. SCATTERED SHOWERS AND THUNDERSTORMS ARE
POSSIBLE MAINLY ALONG AND EAST OF THE VALLEY...BUT TIMING AND
COVERAGE UNCERTAINTY PRECLUDES MENTION IN 12 UTC TAFS. NORTHWEST
WIND WILL BECOME BREEZY THIS AFTERNOON...WITH OCCASIONAL GUSTS
FROM 25 TO 30 KTS.
&&
.HYDROLOGY...
ISSUED AT 930 PM CDT THU JUN 27 2013
RUNOFF CONTINUES TO MAKE ITS WAY INTO THE RED RIVER FROM AREA
TRIBUTARIES. TRENDS CONTINUE TO BE ON TARGET FROM THE MORNING
FORECAST UPDATE FOR THE RIVER POINTS. THE RED RIVER AT FARGO IS
STILL FORECAST TO CREST NEAR MAJOR FLOOD STAGE TOWARDS LATE TODAY
OR TONIGHT. OTHERWISE...RISES ARE EXPECTED TO CONTINUE OVER THE
NEXT FEW DAYS ON CENTRAL AND NORTHERN SECTIONS OF THE RED...WITH A
FEW FORECAST POINTS EXPECTED TO RISE ABOVE MINOR FLOOD STAGE.
WAHPETON REMAINS BELOW FLOOD STAGE AND IS ANTICIPATED TO CONTINUE
FALLING. HOWEVER...EXPECTED RELEASES FROM WHITE ROCK DAM MAY SLOW
THE RECESSION OF RIVER LEVELS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...DK
SHORT TERM...ROGERS
LONG TERM...ROGERS/FRAZIER
AVIATION...ROGERS
HYDROLOGY...HOPKINS
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
704 AM CDT FRI JUN 28 2013
.UPDATE...
ISSUED AT 704 AM CDT FRI JUN 28 2013
WESTERN EDGE OF STRATOCUMULUS DECK NOW EXTENDS FROM HALLOCK TO
MAHNOMEN TO PARK RAPIDS AND IS SLOWLY EXPANDING TO THE SOUTH AND
WEST AROUND 10 KTS. WITH SUNRISE...EXPECT THERMAL CU TO DEVELOP
THROUGH THE DAY...RESULTING IN PARTLY TO MOSTLY CLOUDY SKIES BY
THIS AFTERNOON. ADJUSTED SKY/POP GRIDS TO REFLECT LATEST
OBSERVATIONS. OTHERWISE...FORECAST IS ON TRACK WITH NO MAJOR
CHANGES NEEDED AT THIS TIME.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 350 AM CDT FRI JUN 28 2013
CHALLENGES INCLUDE CLOUD COVER/PRECIPITATION CHANCES TODAY AND
THEN TEMPERATURES THROUGH THE PERIOD. GFS/NAM/ECMWF/GEM ARE IN
GOOD AGREEMENT...BUT WILL LEAN ON LATEST RAP GUIDANCE FOR NEAR TERM
FORECAST.
FOR TODAY...STRATOCUMULUS DECK ACROSS NORTH-CENTRAL MN WILL EXPAND
SOUTH AND WEST THROUGH THE DAY GIVEN CONVECTIVE TEMPERATURES IN
THE UPPER 60S TO MID 70S. WITH A 100 KT 300 HPA JET STREAK MOVING
THROUGH NORTHWEST FLOW ALOFT AND 500 TO 1000 J/KG OF MLCAPE...
SOME OF THESE THERMAL CU MAY GIVE WAY TO SCATTERED AFTERNOON
SHOWERS AND THUNDERSTORMS. REMOVED POPS ALONG AND WEST OF THE
VALLEY THIS MORNING WITH A MOSTLY SUNNY START TO THE DAY...BUT
WILL EXPAND CHANCE POPS SOUTH AND WEST WITH INCREASING CLOUD COVER
THIS AFTERNOON. BOUNDARY LAYER IS 3 TO 6 C COLDER THAN YESTERDAY...
SO EXPECT DAYTIME HIGHS IN THE 70S. WITH 20 TO 30 KTS AT 850 HPA
TO MIX TO THE SURFACE...EXPECT ANOTHER BREEZY AFTERNOON WITH WINDS
FROM 15 TO 20 MPH AND OCCASIONAL GUSTS UP TO 30 MPH.
THERMAL CU WILL DISSIPATE AFTER SUNSET...BUT EXPECT SOME THICKER
CLOUD COVER TO TAKE ITS TIME MOVING OUT OF THE REGION OVERNIGHT.
WINDS WILL SUBSIDE WITH SURFACE HIGH PRESSURE BUILDING ACROSS THE
REGION. OVERNIGHT LOWS WILL BE IN THE 50S.
MOST OF SATURDAY WILL BE DRY...BUT DID KEEP 20 POPS REGION-WIDE
THROUGH THE DAY AS OPERATIONAL MODELS PAINT SEEMINGLY RANDOM LIGHT
QPF IN ASSOCIATION WITH A WEAK SHORT-WAVE ALOFT. SURFACE TO MID-
LEVEL FORCING IS WEAK...SO EXPECT MINIMAL ACCUMULATION WITH ANY
SHOWERS THAT DO DEVELOP. ANOTHER COOLER DAY WITH HIGHS AGAIN IN
THE 70S.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 350 AM CDT FRI JUN 28 2013
SURFACE PRESSURE RIDGE WILL SLIDE SLOWLY ACROSS THE NORTHERN
PLAINS SUNDAY AND MONDAY RESULTING IN DRY...MOSTLY SUNNY
CONDITIONS. WINDS WILL BE LIGHT AND TEMPERATURES WILL BE NEAR
SEASONAL NORMALS WITH HIGHS IN THE UPPER 70S TO LOWER 80S.
A BLEND OF THE GFS/ECMWF TO BE FOLLOWED EARLY IN THE EXTENDED THEN
TRENDING TOWARD THE GFS IN DAYS 5-7. THE UPPER PATTERN AMPLIFIES
DURING THE PERIOD WITH RIDGING OVER THE WRN CONUS AND TROF OVER THE
ERN THIRD OF THE COUNTRY. THE RIDGING OUT WEST WILL RETROGRADE
SOMEWHAT WEST ALLOWING FOR PIECES OF S/WV ENERGY TO SLIDE DOWN THE
BACK SIDE OF THE TROF BY TUE/TUE NIGHT. A FRONTAL BOUNDARY ACROSS
THE REGION WILL HELP FOCUS PRECIPITATION TUE-THU WITH WED BEING THE
MOST OPTIMAL PERIOD FOR SCATTERED SHRA/TSRA. THE BOUNDARY IS
EXPECTED TO WEAKEN BY THU. TEMPERATURES WILL BE TEMPERED WITH HIGHS
IN THE UPPER 70S TO AROUND 80 THROUGH THE WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 704 AM CDT FRI JUN 28 2013
WESTERN EDGE OF MVFR/IFR CLOUD DECK EXTENDS ALONG A KHCO-KMAH0-
KPKD LINE AND WILL CONTINUE TO SLIDE SOUTH AND WEST AROUND 10 KTS.
CEILINGS SHOULD LIFT TO VFR CONDITIONS BY THIS AFTERNOON. CLEAR
SKIES AT KGFK/KFAR/KDVL THIS MORNING WILL FILL-IN WITH THERMAL CU
THROUGHOUT THE DAY. SCATTERED SHOWERS AND THUNDERSTORMS ARE
POSSIBLE MAINLY ALONG AND EAST OF THE VALLEY...BUT TIMING AND
COVERAGE UNCERTAINTY PRECLUDES MENTION IN 12 UTC TAFS. NORTHWEST
WIND WILL BECOME BREEZY THIS AFTERNOON...WITH OCCASIONAL GUSTS
FROM 25 TO 30 KTS.
&&
.HYDROLOGY...
ISSUED AT 930 PM CDT THU JUN 27 2013
RUNOFF CONTINUES TO MAKE ITS WAY INTO THE RED RIVER FROM AREA
TRIBUTARIES. TRENDS CONTINUE TO BE ON TARGET FROM THE MORNING
FORECAST UPDATE FOR THE RIVER POINTS. THE RED RIVER AT FARGO IS
STILL FORECAST TO CREST NEAR MAJOR FLOOD STAGE TOWARDS LATE TODAY
OR TONIGHT. OTHERWISE...RISES ARE EXPECTED TO CONTINUE OVER THE
NEXT FEW DAYS ON CENTRAL AND NORTHERN SECTIONS OF THE RED...WITH A
FEW FORECAST POINTS EXPECTED TO RISE ABOVE MINOR FLOOD STAGE.
WAHPETON REMAINS BELOW FLOOD STAGE AND IS ANTICIPATED TO CONTINUE
FALLING. HOWEVER...EXPECTED RELEASES FROM WHITE ROCK DAM MAY SLOW
THE RECESSION OF RIVER LEVELS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...ROGERS
SHORT TERM...ROGERS
LONG TERM...ROGERS/FRAZIER
AVIATION...ROGERS
HYDROLOGY...HOPKINS
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1032 AM CDT FRI JUN 28 2013
.UPDATE...
MORNING FORECAST UPDATE.
&&
.DISCUSSION...
STRONG UPPER LEVEL RIDGE REALLY HOLDING OVER THE 4 CORNERS/GREAT
BASIN REGION THIS MORNING. UPPER LEVEL FLOW MORE NORTHERLY TODAY
AS EXPECTED WITH UPPER LOW TAKING SHAPE OVER THE GREAT LAKES. SFC
FRONT LOOKS TO BE PUSHING INTO THE RED RIVER REGION. MORNING 850MB
ANALYSIS HAS TEMPS A TOUCH LOWER THAN EXPECTED FROM YESTERDAY`S
FORECAST. THERMAL RIDGE STILL SHOULD SLIDE OVER THE ARE LATER THIS
AFTERNOON WAS 850MB WINDS TURN MORE NORTHERLY. SFC WINDS SHOULD
CONTINUE FROM SW/W AND PERHAPS TURN NW LATER THIS AFTERNOON. THINK
INLAND AREAS SHOULD REACH 98-102F RANGE. TEMPS AT GLS WILL BE
TRICKY AS CURRENT WIND FROM W WHICH COULD HELP LEAD TO ADDITIONAL
HEATING. OVERALL THINK FORECAST IS ON TRACK WITH CURRENT OBS AND
TRENDS. WILL NOT DO AN UPDATE AT THIS TIME.
39
&&
.PREV DISCUSSION... /ISSUED 616 AM CDT FRI JUN 28 2013/
DISCUSSION...
SEE AVIATION FOR 12Z TAF ISSUANCE.
AVIATION...
IFR AND MVFR STRATUS DECK HAS MADE ITS WAY INTO PARTS OF SOUTHEAST
TEXAS THIS MORNING. STRATUS DECK SHOULD STAY CONFINED TO
KCLL...KUTS...AND KCXO TERMINALS THIS MORNING AND BE DISSIPATED BY
10AM. ISSUE FOR TODAY WILL BE A BOUNDARY POSSIBLY MAKING ITS WAY
DOWN INTO THE NORTHERN TERMINALS DURING THE AFTERNOON. THERE IS A
A VERY SLIGHT CHANCE OF A STRAY SHOWER OR THUNDERSTORM AT THE FAR
NORTHERN TERMINALS OF KCLL AND KUTS.
WINDS SHOULD BE OUT OF THE WSW UNTIL THE AFTERNOON WHEN THE SEA
BREEZE MOVES INLAND. AFTER THE SEA BREEZE PUSHES INLAND WINDS
SHOULD SWITCH TOWARDS A MORE SOUTHERLY COMPONENT. VFR CONDITIONS
WILL PREVAIL THROUGH TODAY AFTER MORNING STRATUS BURNS OFF. 23
PREV DISCUSSION... /ISSUED 433 AM CDT FRI JUN 28 2013/
DISCUSSION...
A STRONG UPPER LEVEL RIDGE OF HIGH PRESSURE IS CENTERED OVER
SOUTHERN UTAH WITH THE RIDGE EASTWARD INTO EAST TEXAS. 850 MB
TEMPS CONTINUE TO WARM WITH KCRP NOW UP TO 22 C AND KLCH NOW UP TO
20 C. 700 MB TEMPS ALSO CONTINUE TO WARM AND ARE NOW UP TO 13 C.
MAX TEMPS TODAY WILL PROBABLY BE 2-3 DEGREES WARMER THAN
YESTERDAY. NAM 12 STILL HINTING THAT A SEA BREEZE CIRCULATION
WILL DEVELOP AND FEEL THIS WILL HINDER THE TEMPERATURE RISE AT
COASTAL SITES TODAY. THERE WILL BE MORE OF AN OFFSHORE FLOW ON
SATURDAY AND FEEL COASTAL SITES COULD GET PLENTY WARM AT THAT
TIME. A WEAK BOUNDARY WILL APPROACH THE EXTREME NORTH PART OF SE
TX THIS EVENING AND STALL. THE 4 KM WRF...THE RAP AND 06Z NAM 12
ARE NOW DEVELOPING SOME PCPN ALONG THE BOUNDARY. WILL SOMEWHAT
RELUCTANTLY ADD 20 POPS OVER THE EXTREME NORTH FROM 00-06Z. THE
BOUNDARY WILL CROSS SE TX ON SATURDAY WITH 500 HEIGHTS SLOWLY
DROPPING. FEEL A WARM START AND DRIER AIR ADVECTING INTO THE
REGION WILL COMPENSATE FOR THE LOWER HEIGHTS SO WILL MAINTAIN VERY
WARM TEMPS FOR SAT AFTN. A S/WV WILL MOVE SE ON THE PERIPHERY OF
THE UPPER RIDGE LATE SAT NIGHT INTO SUNDAY. THE TEXAS TECH WRF
SHOWS A SWATH OF PCPN DEVELOPING IN THE NW FLOW AND MOVING INTO
THE AREA BETWEEN 06-12Z SUNDAY. ADDED 20 POPS FOR THIS POTENTIAL
ON SAT NIGHT. DRIER LOW LEVEL AIR WILL ALLOW MIN TEMPS TO TREND
SLIGHTLY COOLER SUNDAY MORNING AND LOWER HEIGHTS WILL PORTEND
COOLER MAX TEMPS ON SUNDAY AFTN.
THE UPPER RIDGE RETREATS WEST ON SUNDAY AND BEYOND AS AN UPPER
LEVEL TROUGH OVER THE EASTERN U.S. RETROGRADES WEST. HEIGHTS WILL
LOWER OVER SE TX WITH A SUBTLE DECREASE IN AFTERNOON TEMPS
EXPECTED. THE AIR MASS WILL BE RATHER DRY SO AM STILL EXPECTING
MAX TEMPS TO WARM INTO THE MIDDLE 90S. MOISTURE LEVELS BEGIN TO
DEEPEN ON WEDNESDAY SO AM EXPECTING AN INCREASE IN CLOUD COVER AND
HIGHER RAIN CHANCES. THE UPPER LEVEL TROUGH WILL LINGER ACROSS
THE CENTRAL PLAINS THROUGH THE END OF NEXT WEEK. WILL CARRY RAIN
CHANCES...ADDITIONAL CLOUD COVER AND COOLER TEMPS IN RESPONSE TO
THE UPPER TROUGH. 43
MARINE...
LIGHT TO MODERATE WIND SPEEDS WILL REMAIN THROUGH THE AFTERNOON.
WINDS SHOULD THEN BECOME MODERATE AND APPROACH SCEC CRITERIA LATE
FRIDAY INTO EARLY SATURDAY AS THE THERMAL GRADIENT INCREASES ALONG
WITH THE BOUNDARY MOVING SOUTHWARDS. THE BOUNDARY SHOULD THEN STALL
OUT NEAR THE COAST ON SATURDAY THEN HAVE THE WINDS BRIEFLY SWITCH TO
THE NORTH AS A SECONDARY BOUNDARY MARCHES SOUTHWARD. THE BOUNDARY
SHOULD THEN WASH OUT AND PULL NORTHWARDS EARLY WEDNESDAY GIVING WAY
TO ONSHORE WINDS. 23
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 102 75 102 72 96 / 0 20 10 20 20
HOUSTON (IAH) 100 76 100 75 97 / 0 10 10 20 20
GALVESTON (GLS) 94 80 97 78 96 / 10 10 10 10 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...39
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
616 AM CDT FRI JUN 28 2013
.DISCUSSION...
SEE AVIATION FOR 12Z TAF ISSUANCE.
&&
.AVIATION...
IFR AND MVFR STRATUS DECK HAS MADE ITS WAY INTO PARTS OF SOUTHEAST
TEXAS THIS MORNING. STRATUS DECK SHOULD STAY CONFINED TO
KCLL...KUTS...AND KCXO TERMINALS THIS MORNING AND BE DISSIPATED BY
10AM. ISSUE FOR TODAY WILL BE A BOUNDARY POSSIBLY MAKING ITS WAY
DOWN INTO THE NORTHERN TERMINALS DURING THE AFTERNOON. THERE IS A
A VERY SLIGHT CHANCE OF A STRAY SHOWER OR THUNDERSTORM AT THE FAR
NORTHERN TERMINALS OF KCLL AND KUTS.
WINDS SHOULD BE OUT OF THE WSW UNTIL THE AFTERNOON WHEN THE SEA
BREEZE MOVES INLAND. AFTER THE SEA BREEZE PUSHES INLAND WINDS
SHOULD SWITCH TOWARDS A MORE SOUTHERLY COMPONENT. VFR CONDITIONS
WILL PREVAIL THROUGH TODAY AFTER MORNING STRATUS BURNS OFF. 23
&&
.PREV DISCUSSION... /ISSUED 433 AM CDT FRI JUN 28 2013/
DISCUSSION...
A STRONG UPPER LEVEL RIDGE OF HIGH PRESSURE IS CENTERED OVER
SOUTHERN UTAH WITH THE RIDGE EASTWARD INTO EAST TEXAS. 850 MB
TEMPS CONTINUE TO WARM WITH KCRP NOW UP TO 22 C AND KLCH NOW UP TO
20 C. 700 MB TEMPS ALSO CONTINUE TO WARM AND ARE NOW UP TO 13 C.
MAX TEMPS TODAY WILL PROBABLY BE 2-3 DEGREES WARMER THAN
YESTERDAY. NAM 12 STILL HINTING THAT A SEA BREEZE CIRCULATION
WILL DEVELOP AND FEEL THIS WILL HINDER THE TEMPERATURE RISE AT
COASTAL SITES TODAY. THERE WILL BE MORE OF AN OFFSHORE FLOW ON
SATURDAY AND FEEL COASTAL SITES COULD GET PLENTY WARM AT THAT
TIME. A WEAK BOUNDARY WILL APPROACH THE EXTREME NORTH PART OF SE
TX THIS EVENING AND STALL. THE 4 KM WRF...THE RAP AND 06Z NAM 12
ARE NOW DEVELOPING SOME PCPN ALONG THE BOUNDARY. WILL SOMEWHAT
RELUCTANTLY ADD 20 POPS OVER THE EXTREME NORTH FROM 00-06Z. THE
BOUNDARY WILL CROSS SE TX ON SATURDAY WITH 500 HEIGHTS SLOWLY
DROPPING. FEEL A WARM START AND DRIER AIR ADVECTING INTO THE
REGION WILL COMPENSATE FOR THE LOWER HEIGHTS SO WILL MAINTAIN VERY
WARM TEMPS FOR SAT AFTN. A S/WV WILL MOVE SE ON THE PERIPHERY OF
THE UPPER RIDGE LATE SAT NIGHT INTO SUNDAY. THE TEXAS TECH WRF
SHOWS A SWATH OF PCPN DEVELOPING IN THE NW FLOW AND MOVING INTO
THE AREA BETWEEN 06-12Z SUNDAY. ADDED 20 POPS FOR THIS POTENTIAL
ON SAT NIGHT. DRIER LOW LEVEL AIR WILL ALLOW MIN TEMPS TO TREND
SLIGHTLY COOLER SUNDAY MORNING AND LOWER HEIGHTS WILL PORTEND
COOLER MAX TEMPS ON SUNDAY AFTN.
THE UPPER RIDGE RETREATS WEST ON SUNDAY AND BEYOND AS AN UPPER
LEVEL TROUGH OVER THE EASTERN U.S. RETROGRADES WEST. HEIGHTS WILL
LOWER OVER SE TX WITH A SUBTLE DECREASE IN AFTERNOON TEMPS
EXPECTED. THE AIR MASS WILL BE RATHER DRY SO AM STILL EXPECTING
MAX TEMPS TO WARM INTO THE MIDDLE 90S. MOISTURE LEVELS BEGIN TO
DEEPEN ON WEDNESDAY SO AM EXPECTING AN INCREASE IN CLOUD COVER AND
HIGHER RAIN CHANCES. THE UPPER LEVEL TROUGH WILL LINGER ACROSS
THE CENTRAL PLAINS THROUGH THE END OF NEXT WEEK. WILL CARRY RAIN
CHANCES...ADDITIONAL CLOUD COVER AND COOLER TEMPS IN RESPONSE TO
THE UPPER TROUGH. 43
MARINE...
LIGHT TO MODERATE WIND SPEEDS WILL REMAIN THROUGH THE AFTERNOON.
WINDS SHOULD THEN BECOME MODERATE AND APPROACH SCEC CRITERIA LATE
FRIDAY INTO EARLY SATURDAY AS THE THERMAL GRADIENT INCREASES ALONG
WITH THE BOUNDARY MOVING SOUTHWARDS. THE BOUNDARY SHOULD THEN STALL
OUT NEAR THE COAST ON SATURDAY THEN HAVE THE WINDS BRIEFLY SWITCH TO
THE NORTH AS A SECONDARY BOUNDARY MARCHES SOUTHWARD. THE BOUNDARY
SHOULD THEN WASH OUT AND PULL NORTHWARDS EARLY WEDNESDAY GIVING WAY
TO ONSHORE WINDS. 23
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 102 75 102 72 96 / 0 20 10 20 20
HOUSTON (IAH) 100 76 100 75 97 / 0 10 10 20 20
GALVESTON (GLS) 94 80 97 78 96 / 10 10 10 10 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...43
AVIATION/MARINE...23
AREA FORECAST DISCUSSION
NWS TUCSON AZ
205 PM MST FRI JUN 28 2013
.SYNOPSIS...EXPECT VERY HOT DAYTIME TEMPERATURES THROUGH SUNDAY.
THERE IS ALSO A SLIGHT CHANCE OF MAINLY MOUNTAIN THUNDERSTORMS EAST
OF TUCSON SATURDAY. GRADUALLY INCREASING MOISTURE WILL THEN LEAD TO
THE DAILY CYCLE OF MAINLY AFTERNOON AND EVENING THUNDERSTORMS DURING
THE UPCOMING WEEK. THE INCREASED MOISTURE WILL ALSO PROVIDE A
GRADUAL MODERATION IN DAYTIME TEMPERATURES NEXT WEEK.
&&
.DISCUSSION...599 DM HIGH PRESSURE CENTERED NEAR THE FOUR CORNERS
PROVIDING A GENERALLY LIGHT ELY FLOW REGIME ACROSS SE AZ THIS
AFTERNOON. 28/17Z RUC HRRR DEPICTED TWO CLUSTERS OF SHOWERS/TSTMS TO
MOVE WWD ACROSS THE WHITE MOUNTAINS INTO NRN GRAHAM COUNTY NORTH OF
SAFFORD LATE THIS AFTERNOON AND EARLY THIS EVENING.
THUS...HAVE CONFINED A SLIGHT CHANCE OF SHOWERS/TSTMS TO THE WHITE
MOUNTAINS AND NRN GRAHAM COUNTY THIS EVENING. POPS WERE REDUCED TO
LESS THAN 10 PERCENT ELSEWHERE. DRY CONDITIONS TO OCCUR AREA-WIDE
LATE TONIGHT AND SAT MORNING. SLIGHTLY GREATER COVERAGE OF SHOWERS/
TSTMS TO OCCUR SAT AFTERNOON AND SAT EVENING AS THE UPPER HIGH
REMAINS QUASI-STATIONARY NEAR THE FOUR CORNERS REGION.
28/12Z GFS/ECMWF WERE SIMILAR WITH DEPICTING A GRADUAL INCREASE OF
MOISTURE STARTING SUN AND CONTINUING DURING THE UPCOMING WEEK. ELY
MID-LEVEL STEERING FLOW SHOULD INCREASE SUFFICIENTLY TO JUSTIFY A
SLIGHT CHANCE OF SHOWERS/TSTMS AS FAR WEST AS THE TUCSON METRO AREA
SUN AFTERNOON AND SUN EVENING. CHANCE-CATEGORY POPS TO OCCUR SUN
AFTERNOON AND SUN EVENING ACROSS THE MOUNTAINS OF GREENLEE/GRAHAM/
COCHISE COUNTIES. EXPECT A SIMILAR POP SCENARIO MON AFTERNOON AND
MON EVENING.
THEREAFTER...POPS WERE TRENDED UPWARD BY WED AS THE GFS/ECMWF
CONTINUED TO DEPICT GRADUALLY INCREASING MOISTURE ACROSS THE AREA.
HAVE OPTED FOR THE HIGHEST POPS TO OCCUR WED...WITH CHANCE-CATEGORY
POPS FROM TUCSON EWD/SWD AND ONLY SINGLE DIGIT POPS ACROSS WRN PIMA
COUNTY. MID-LEVEL STEERING FLOW IS THEN PROGGED TO BECOME MORE
NORTHERLY BY LATE NEXT WEEK AS THE WRN CONUS HIGH SHIFTS INTO SRN
CALIFORNIA. HAVE REDUCED POPS SLIGHTLY THUR-FRI. HOWEVER...EXPECT
AT LEAST A SLIGHT CHANCE OF SHOWERS/TSTMS FROM TUCSON EWD/SWD TO
CONTINUE THUR-FRI DURING THE AFTERNOON AND EVENING HOURS.
AS FOR TEMPS...HAVE MAINTAINED THE EXCESSIVE HEAT WARNING THRU 9 PM
MST SUN. CONFIDENCE IS SOMEWHAT LOW THAT WARNING CRITERIA WILL BE
WIDESPREAD SUN AFTERNOON. THUS...FOR CONTINUITY...HAVE KEPT THE
EXCESSIVE HEAT WARNING FOR SUN. THEREAFTER...EXPECT A VERY GRADUAL
MODERATION IN DAYTIME TEMPS MON-FRI.
&&
.AVIATION...ISOLD -TSRA MAINLY NEAR MTNS EAST OF KTUS THRU THIS
EVENING AND AGAIN SATURDAY AFTERNOON. OTHERWISE...SCT-BKN CLOUDS
MOSTLY ABOVE 12K FT AGL THRU SATURDAY AFTERNOON OR 30/00Z. SURFACE
WIND TONIGHT AND SATURDAY MORNING MOSTLY ELY/SELY 10-15 KTS WITH
GUSTS TO 20 KTS. SURFACE WIND SATURDAY AFTERNOON VARIABLE IN
DIRECTION AT LESS THAN 10 KTS. TEMPERATURES OF 100 DEGREES OR HIGHER
WILL PRODUCE INCREASED TAKE OFF LENGTHS DURING PEAK HEATING THIS
WEEKEND. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...THERE IS A SLIGHT CHANCE OF AFTERNOON AND EVENING
THUNDERSTORMS ACROSS THE HIGHER TERRAIN EAST OF TUCSON THIS WEEKEND.
THEREAFTER...GRADUALLY INCREASING MOISTURE WILL THEN PRODUCE THE
DAILY CYCLE OF MAINLY AFTERNOON AND EVENING THUNDERSTORMS NEXT WEEK.
OTHERWISE...VERY HOT TEMPERATURES WILL CONTINUE THIS WEEKEND. THE
INCREASING MOISTURE WILL LEAD TO A GRADUAL DECREASE IN DAYTIME
TEMPERATURES DURING THE UPCOMING WEEK. GUSTY WINDS WILL PREVAIL
DURING THE AFTERNOON HOURS DUE TO STRONG DAYTIME HEATING.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...
EXCESSIVE HEAT WARNING UNTIL 9 PM MST SUNDAY FOR AZZ501>506-509-
515.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
BF
AREA FORECAST DISCUSSION
NWS PUEBLO CO
315 PM MDT FRI JUN 28 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 256 PM MDT FRI JUN 28 2013
...MORE STORMS FOR THE PLAINS LATER TODAY...
THE TWO MAIN CONCERNS THIS AFTERNOON/TONIGHT AND TOMORROW ARE THE
CHANCES OF SEVERE THUNDERSTORMS ACROSS THE I-25 CORRIDOR AND EASTERN
PLAINS...AND HEAVY PRECIPITATION IN AND AROUND BURN AREAS.
CURRENTLY...A SMALL CIRCULATION 20 TO 30 MILES NNW OF COS...WITH ASSOCIATED
QUASISTATIONARY BOUNDARY...IS HELPING TO ENHANCE THUNDERSTORM
DEVELOPMENT ALONG THE HIGHER TERRAIN. ESPECIALLY IN TELLER COUNTY
WHERE NUMEROUS CG STRIKES HAVE BEEN DETECTED WITH A STRONG CELL
CURRENTLY MOVING SOUTHWARD TOWARDS CANON CITY. THE 12Z GFS40 PV15
ALSO SHOWS A WEAK MIDLEVEL DISTURBANCE COMING THROUGH THE
NORTHWEST FLOW AROUND 00Z TONIGHT. THESE INGREDIENTS...ALONG WITH
DEWPOINTS IN THE 30`S AND 40`S ALONG THE I-25 CORRIDOR...WILL AID
IN KEEPING THUNDERSTORMS GOING AFTER SUNSET. SOME OF THESE STORMS
COULD BRIEFLY BECOME SEVERE...MINALY DUE TO GUSTY OUTFLOW WINDS.
LATER TONIGHT...THE HRRR/RAP/NAM12 CONTINUE TO INDICATE
THUNDERSTORMS WILL MOVE SOUTHEAST ACROSS THE PLAINS THROUGH 06Z. THE
MODELS...ESPECIALLY THE HRRR AND RAP...SEEM A BIT OVERDONE ON THE
MOISTURE (CURRENT TD IN LHX IS 26)...BUT STILL FEEL ISOLATED
THUNDERSTORMS WILL BE POSSIBLE ACROSS THE PLAINS TONIGHT.
THE PRIMARY THREAT FROM THESE STORMS WILL LIKELY BE WIND...BUT IF
MOISTURE DOES RETURN VIA A NORTHEASTERLY SURGE AS THE RAP AND HRRR
FORECAST...SOME SMALL HAIL IS POSSIBLE AS 0-6KM BULK SHEAR IS
30-40KTS ACROSS THE PLAINS.
THE NAM12/GFS/EC ALL SHOW ANOTHER...MORE SIGNIFICANT...DISTURBANCE
IN THE NORTHWEST FLOW PUSHING THROUGH THE AREA SATURDAY MORNING.
THIS DISTURBANCE WILL DROP A COLD FRONT THROUGH THE AREA AROUND 12Z
SATURDAY. THIS WILL CREATE GUSTY NORTHEASTERLY WINDS AND HELP DROP
700MB TEMPERATURES TO AROUND 11C...LEADING TO COOLER MAX
TEMPERATURES AND INCREASED MOSITURE ACROSS THE FORECAST AREA.
THUNDERSTORMS ARE LIKELY ONCE AGAIN ACROSS THE MOUNTAINS DURING
THE LATE MORNING AND AFTERNOON. CURRENT ACTIVE BURN AREAS SUCH AS
THE WEST FORK COMPLEX AND EAST PEAK FIRES...ALONG WITH THE WALDO
CANYON SCAR...WILL NEED TO MONITORED FOR FLOODING POTENTIAL
TOMORROW AFTERNOON. THE POTENTIAL WILL EXIST ONCE AGAIN FOR
ISOLATED SEVERE STORMS ACROSS THE EASTERN PLAINS DUE TO THE
INCREASE IS MOISTURE. -PJC
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 256 PM MDT FRI JUN 28 2013
...COOLER TEMPERATURES WITH CONTINUED CHANCES OF RAIN...AND FLASH
FLOODING CONCERNS FOR THE BURN SCARS...
AN ACTIVE PERIOD IS EXPECTED AS THE UPPER LEVEL RIDGE AXIS SHIFTS
WEST AND REMAINS CENTERED THROUGH THE GREAT BASIN. NORTHERLY FLOW
ALOFT IS EXPECTED ACROSS COLORADO THROUGH AT LEAST TUESDAY. AT THE
SURFACE...EXPECT EAST TO SOUTHEAST UPSLOPE SURFACE FLOW TO
CONTINUE WITH DEWPOINTS IN THE 50S ACROSS THE PLAINS SUNDAY.
MODELS SHOW A WEAK DISTURBANCE MOVING THROUGH THE FLOW ALOFT
SUNDAY AND CURRENT MODEL TIMING SHOWS IT MOVING THROUGH SOUTHEAST
COLORADO DURING PEAK HEATING. WITH COOLER AIRMASS IN PLACE...CAPES
IN THE 1000-1500J/KG RANGE ALONG THE SOUTHEAST COLORADO MOUNTAINS...
EXPECT TO HAVE ANOTHER DAY OF CONVECTION FIRING BY EARLY AFTERNOON
OVER THE HIGHER ELEVATIONS. PRIMARY CONCERN WOULD BE FOR LOCALLY
HEAVY RAINFALL TO IMPACT ONE OF THE BURN SCARS
SUNDAY...HOWEVER...WITH ENOUGH SURFACE HEATING...
INSTABILITY...AND FAVORABLE WIND SHEAR PROFILES...A FEW OF THE
STORMS COULD BECOME STRONG TO SEVERE. THIS GENERAL PATTERN
CONTINUES THROUGH TUESDAY ALTHOUGH CAPES AND DEWPOINTS DECREASE
MONDAY AND TUESDAY WHICH WILL LIMIT THE COVERAGE...INTENSITY...AND
RAINFALL POTENTIAL OF THUNDERSTORMS.
ON WEDNESDAY...A STRONG UPPER LEVEL DISTURBANCE MOVES SOUTH
THROUGH THE BACKSIDE OF THE TROF AXIS AND CLOSES OFF OVER THE HIGH
PLAINS THURSDAY. GFS FORECASTS THE CLOSED LOW TO RETROGRADE FRIDAY
TO SOUTHWESTERN SOUTH DAKOTA. THE ECMWF KEEPS THE CLOSED LOW
FARTHER SOUTH...OVER WESTERN KS AND THE OK/TX PANHANDLES. THE GFS
SCENARIO...WHICH HAS BEEN CONSISTENT FOR A FEW RUNS NOW...KEEPS
SOUTHEAST COLORADO IN A COOL AND ACTIVE PATTERN WITH THUNDERSTORM
CHANCES EACH DAY FROM WEDNESDAY THRU FRIDAY. THE ECMWF SCENARIO
KEEPS BEST PRECIPITATION CHANCES TO THE SOUTH AND EAST OF THE CWA.
STILL EXPECT THE COOLER TEMPERATURES AND INCREASED RELATIVE
HUMDITIES TO BRING SOME RELIEF TO WILDFIRE THREAT. STARK
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 256 PM MDT FRI JUN 28 2013
THUNDERSTORMS AND ASSOCIATED OUTFLOW WINDS WILL CONTINUE TO BE THE
MAIN CONCERN AT KALS...KCOS...AND KPUB TONIGHT AND SATURDAY
AFTERNOON. THE BEST CHANCE FOR THUNDERSTORMS WILL BE AT KCOS AND THE
SURROUNDING MOUNTAINS. MVFR CONDITIONS WILL BE POSSIBLE LATER THIS
AFTERNOON AND EVENING AT KCOS. VFR CONDITIONS ARE EXPECTED AT KALS
AND KPUB THROUGH SATURDAY EVENING. -PJC
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...PJC
LONG TERM...STARK
AVIATION...PJC
AREA FORECAST DISCUSSION
NWS NEW YORK NY
130 PM EDT FRI JUN 28 2013
.SYNOPSIS...
A BROAD AREA OF LOW PRESSURE WILL REMAIN OVER THE NORTHEAST AND
IMPACT THE REGION THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK.
THE BERMUDA HIGH WILL STRENGTHEN AND BUILD BACK TOWARD THE
EASTERN SEABOARD BY THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CAPES ALREADY RUNNING 1500-2500 J/KG ACROSS MOST OF THE TRI-STATE
AT 16Z PER LAPS ANALYSIS. HOWEVER CORE OF LOW LEVEL JET IS TO THE
EAST...AND THE REGION IS IN THE RIGHT FRONT QUADRANT OF AN 80+ KT
250 HPA JET PER 12Z RAOBS. SO WHILE HAVE THE CAPE...NOT THE MUCH
THE WAY IN FORCING TO PLAY WITH...OUTSIDE OF RESIDUAL BOUNDARIES
FROM YESTERDAY/S CONVECTION AND LINGERING TROUGH OVER THE LOWER
HUDSON VALLEY/NE NJ. LATEST HRRR AND RUC PAINT A PICTURE OF ISOLD-
SCT CONVECTION FOR REMAINDER OF THE DAY AND THE FORECAST IS
CONSISTENT WITH THIS.
TEMPERATURE FORECAST FOR SLIGHTLY ABOVE NORMAL HIGHS APPEARS ON
TRACK.
THERE IS A HIGH RISK OF RIP CURRENTS AT ALL ATLANTIC OCEAN BEACHES
THROUGH THIS EVENING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
CONVECTION SHOULD DIE DOWN DURING THE EVENING AS IT MOVES EAST
ACROSS LONG ISLAND AND SOUTHERN CT...BUT THEN ANOTHER ROUND OF
SHOWERS AND POSSIBLE TSTMS IS LIKELY LATE TONIGHT INTO SAT
MORNING...ESPECIALLY EAST ACROSS LONG ISLAND AND SOUTHERN CT...AS
A WEAK MID LEVEL IMPULSE MOVES UP THE COAST. LAST TWO RUNS OF THE
ECMWF HAVE BEEN MOST AGGRESSIVE WITH THIS FEATURE...HAVE ACCEPTED
THIS IDEA BUT TEMPERED WITH THE WEAKER GFS SOLUTION.
TEMPERATURES SHOULD CONTINUE TO RUN SLIGHTLY ABOVE SEASONAL NORMS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
THE UNSETTLED WEATHER PATTERN CONTINUES THIS WEEKEND INTO THE
BEGINNING OF NEXT WEEK WITH THE ONGOING THREAT FOR SHOWERS AND
THUNDERSTORMS AS THE REGION SITS BETWEEN A STRONG BERMUDA HIGH/UPPER
LEVEL RIDGE TO THE EAST AND A DEEP UPPER LEVEL TROUGH OVER THE GREAT
LAKES REGION. THIS SYNOPTIC SET UP PROVIDES A CONTINUAL SOUTHERLY
FLOW...USHERING IN WARM...VERY MOIST AIR. THE LATEST 00Z MODEL RUNS
HAVE GENERALLY GOOD AGREEMENT ON THE PLACEMENT OF THESE
FEATURES...WITH ONLY SLIGHT DIVERGENCE TOWARDS THE END OF THE
FORECAST PERIOD.
SURFACE LOW HOVERS OVER SOUTHEASTERN CANADA SAT NIGHT...WITH A
STATIONARY FRONT POSITIONED THROUGH THE TRI STATE AREA. 00Z MODELS
HINT OF A BRIEF PERIOD OF DRYING OUT...WITH PW VALUES ONLY AROUND
1.2/1.3 INCHES FOR SAT NIGHT. MADE MENTION OF CHANCE OF
SHOWERS/THUNDERSTORMS SAT NIGHT AS A SHORTWAVE PIVOTS AROUND THE
EASTERN SIDE OF THE UPPER LEVEL TROUGH. BEST COMBO OF
INSTABILITY/SHEAR LOOKS TO BE FARTHER INLAND NORTH AND WEST OF THE
CITY...BUT A STRONGER TSTM IS POSSIBLE WITH INSTABILITY VALUES
BETWEEN 1000-1500 J/KG AND 0-6KM SHEAR BETWEEN 30 AND 35 KTS. AS THE
NEXT SURFACE LOW TRACKS ALONG THE FRONT TO THE NORTHEAST SUNDAY...PW
VALUES INCREASE GREATLY OVER THE AREA...WITH VALUES AROUND 2.0
INCHES EXPECTED BY THE AFTERNOON ALONG THE CONTINUAL SOUTHERLY FLOW. SHEAR
AND INSTABILITY VALUES REMAIN MARGINAL...WITH THE THINKING THAT
HEAVY RAIN WILL BE THE MAIN THREAT WITH ANY SHOWERS AND
THUNDERSTORMS THAT FORM SUNDAY.
SHOWERS AND THUNDERSTORMS REMAIN LIKELY IN THE FORECAST FOR THE
FIRST PART OF THE WEEK WITH THE STATIONARY FRONT HUGGING THE
NORTHEAST AND MULTIPLE SHORTWAVES SQUEEZING BETWEEN THE UPPER LEVEL
TROUGH TO THE WEST AND THE RIDGE TO THE EAST. BY TUESDAY...THE
BERMUDA HIGH/UPPER LEVEL RIDGE NUDGES INTO THE
NORTHEAST...DIMINISHING THE THREAT FOR WIDESPREAD PRECIPITATION. THE
THREAT FOR THUNDERSTORMS BECOMES MORE DIURNAL AT THIS POINT WITH THE
PASSING SHORTWAVES COMBINED WITH DAY TIME HEATING BECOMING THE MAIN
TRIGGER RATHER THAN THE FRONTAL BOUNDARY. HAVE INCLUDED CHANCE POPS TO
ACCOUNT FOR THIS THROUGH THE END OF THE WEEK...WITH SOME DRYING
FINALLY EXPECTED BY FRIDAY AS THE RIDGE AND SURFACE HIGH TAKE MORE
CONTROL OF THE NORTHEAST AS THE UPPER LEVEL TROUGH FINALLY WEAKENS
AND PROGRESSES EAST.
TEMPS NEAR NORMAL FOR THE PERIOD...WITH HIGHS GENERALLY IN THE 80S
AND LOWS IN THE UPPER 60S TO LOWER 70S.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
GENERALLY VFR THROUGH THIS AFTERNOON. SOME PATCHY MVFR CIGS/VSBYS
POSSIBLE ACROSS EASTERN TERMINALS THROUGH 21Z. SCATTERED SHOWERS AND
THUNDERSTORMS DEVELOP/APPROACH WESTERN TERMINALS BY 22Z...MOVE
THROUGH CITY TERMINALS THROUGH 01Z BEFORE WEAKENING AND MOVING
THROUGH EASTERN TERMINALS BY 04Z-05Z. ISOLATED DEVELOPMENT POSSIBLE
AHEAD OF THIS BUT CONFIDENCE TOO LOW IN LOCATION/TIMING FOR
INCLUSION IN TAFS.
WINDS LIGHTEN OVERNIGHT WITH CONFIDENCE INCREASING IN MVFR TO IFR
CONDITIONS AT COASTAL TERMINALS. POSSIBLY LOWER IN SPOTS. CIGS/VSBYS
LIFT AFTER 13Z SATURDAY.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KEWR FCSTER COMMENTS: LOW-MODERATE CONFIDENCE IN COVERAGE OF TSTMS.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KJFK FCSTER COMMENTS: LOW-MODERATE CONFIDENCE IN COVERAGE OF TSTMS.
KLGA FCSTER COMMENTS: LOW-MODERATE CONFIDENCE IN COVERAGE OF TSTMS.
KTEB FCSTER COMMENTS: LOW-MODERATE CONFIDENCE IN COVERAGE OF TSTMS.
KHPN FCSTER COMMENTS: LOW-MODERATE CONFIDENCE IN COVERAGE OF TSTMS.
KISP FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED FOR SHOWERS.
.OUTLOOK FOR 18Z SAT THROUGH WEDNESDAY...
.SAT-WED...SUB VFR POSSIBLE AT TIMES WITH PERIODS OF SHOWERS AND
TSTMS.
&&
.MARINE...
MINOR CHANGES MADE THIS UPDATE TO REFLECT THE LATEST CHANGES IN
OBSERVATIONS AND GUIDANCE. FORECAST APPEARS ON TRACK.
SCA REMAINS UP ON THE OCEAN WATERS INTO SATURDAY WITH SEAS AROUND
5 FT...AND POSSIBLE GUSTS UP TO 25 KTS.
SCA CONDITIONS EXPECTED ON THE OCEAN WATERS THROUGH THE WEEKEND WITH
SEAS BETWEEN 7 AND 9 FT. WIND GUSTS MAY TOUCH 25 KTS AS WELL DURING
THIS TIME. SEAS REMAIN ELEVATED DURING THE COMING WEEK WITH A
PERSISTENT SOUTHERLY FLOW CONTINUALLY BUILDING UP THE SEAS. WINDS
HOWEVER EXPECTED TO REMAIN BELOW SCA CRITERIA...SO ALL WATERS OTHER
THAN THE OCEAN SHOULD REMAIN SUB SCA.
WILL CONTINUE TO UNDERCUT WAVE WATCH III SEAS BY A FOOT OR SO.
&&
.HYDROLOGY...
CONFIDENCE IN FLASH FLOOD WATCH IS DECREASING. IF CURRENT
CONVECTIVE TRENDS HOLD...COULD CANCEL THIS AFTERNOON...BUT FOR NOW
WILL LEAVE UP FOR NYC/NE NJ/LOWER HUDSON VALLEY/SW CT.
SHOWERS AND THUNDERSTORMS SUNDAY INTO MONDAY MAY PRODUCE HEAVY
RAINFALL...WITH LOCALIZED FLOODING...ESPECIALLY OVER URBAN AND POOR
DRAINAGE AREAS. STILL TOO EARLY AT THIS TIME TO DETERMINE RAINFALL
TOTALS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND STREAMS...INCLUDING
OBSERVED AND FORECAST RIVER STAGES...PLEASE VISIT THE ADVANCED
HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...FLASH FLOOD WATCH UNTIL 9 PM EDT THIS EVENING FOR CTZ005-006-
009-010.
NY...FLASH FLOOD WATCH UNTIL 9 PM EDT THIS EVENING FOR NYZ067>075-
176>179.
NJ...FLASH FLOOD WATCH UNTIL 9 PM EDT THIS EVENING FOR NJZ002-004-
006-103>108.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR ANZ350-353-
355.
&&
$$
SYNOPSIS...GOODMAN/SEARS
NEAR TERM...GOODMAN/MALOIT
SHORT TERM...GOODMAN
LONG TERM...SEARS
AVIATION...BC
MARINE...GOODMAN/MALOIT/SEARS
HYDROLOGY...GOODMAN/SEARS
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1257 PM EDT FRI JUN 28 2013
.SYNOPSIS...
A BROAD AREA OF LOW PRESSURE WILL REMAIN OVER THE NORTHEAST AND
IMPACT THE REGION THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK.
THE BERMUDA HIGH WILL STRENGTHEN AND BUILD BACK TOWARD THE
EASTERN SEABOARD BY THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CAPES ALREADY RUNNING 1500-2500 J/KG ACROSS MOST OF THE TRI-STATE
AT 16Z PER LAPS ANALYSIS. HOWEVER CORE OF LOW LEVEL JET IS TO THE
EAST...AND THE REGION IS IN THE RIGHT FRONT QUADRANT OF AN 80+ KT
250 HPA JET PER 12Z RAOBS. SO WHILE HAVE THE CAPE...NOT THE MUCH
THE WAY IN FORCING TO PLAY WITH...OUTSIDE OF RESIDUAL BOUNDARIES
FROM YESTERDAY/S CONVECTION AND LINGERING TROUGH OVER THE LOWER
HUDSON VALLEY/NE NJ. LATEST HRRR AND RUC PAINT A PICTURE OF ISOLD-
SCT CONVECTION FOR REMAINDER OF THE DAY AND THE FORECAST IS
CONSISTENT WITH THIS.
TEMPERATURE FORECAST FOR SLIGHTLY ABOVE NORMAL HIGHS APPEARS ON
TRACK.
THERE IS A HIGH RISK OF RIP CURRENTS AT ALL ATLANTIC OCEAN BEACHES
THROUGH THIS EVENING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
CONVECTION SHOULD DIE DOWN DURING THE EVENING AS IT MOVES EAST
ACROSS LONG ISLAND AND SOUTHERN CT...BUT THEN ANOTHER ROUND OF
SHOWERS AND POSSIBLE TSTMS IS LIKELY LATE TONIGHT INTO SAT
MORNING...ESPECIALLY EAST ACROSS LONG ISLAND AND SOUTHERN CT...AS
A WEAK MID LEVEL IMPULSE MOVES UP THE COAST. LAST TWO RUNS OF THE
ECMWF HAVE BEEN MOST AGGRESSIVE WITH THIS FEATURE...HAVE ACCEPTED
THIS IDEA BUT TEMPERED WITH THE WEAKER GFS SOLUTION.
TEMPERATURES SHOULD CONTINUE TO RUN SLIGHTLY ABOVE SEASONAL NORMS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
THE UNSETTLED WEATHER PATTERN CONTINUES THIS WEEKEND INTO THE
BEGINNING OF NEXT WEEK WITH THE ONGOING THREAT FOR SHOWERS AND
THUNDERSTORMS AS THE REGION SITS BETWEEN A STRONG BERMUDA HIGH/UPPER
LEVEL RIDGE TO THE EAST AND A DEEP UPPER LEVEL TROUGH OVER THE GREAT
LAKES REGION. THIS SYNOPTIC SET UP PROVIDES A CONTINUAL SOUTHERLY
FLOW...USHERING IN WARM...VERY MOIST AIR. THE LATEST 00Z MODEL RUNS
HAVE GENERALLY GOOD AGREEMENT ON THE PLACEMENT OF THESE
FEATURES...WITH ONLY SLIGHT DIVERGENCE TOWARDS THE END OF THE
FORECAST PERIOD.
SURFACE LOW HOVERS OVER SOUTHEASTERN CANADA SAT NIGHT...WITH A
STATIONARY FRONT POSITIONED THROUGH THE TRI STATE AREA. 00Z MODELS
HINT OF A BRIEF PERIOD OF DRYING OUT...WITH PW VALUES ONLY AROUND
1.2/1.3 INCHES FOR SAT NIGHT. MADE MENTION OF CHANCE OF
SHOWERS/THUNDERSTORMS SAT NIGHT AS A SHORTWAVE PIVOTS AROUND THE
EASTERN SIDE OF THE UPPER LEVEL TROUGH. BEST COMBO OF
INSTABILITY/SHEAR LOOKS TO BE FARTHER INLAND NORTH AND WEST OF THE
CITY...BUT A STRONGER TSTM IS POSSIBLE WITH INSTABILITY VALUES
BETWEEN 1000-1500 J/KG AND 0-6KM SHEAR BETWEEN 30 AND 35 KTS. AS THE
NEXT SURFACE LOW TRACKS ALONG THE FRONT TO THE NORTHEAST SUNDAY...PW
VALUES INCREASE GREATLY OVER THE AREA...WITH VALUES AROUND 2.0
INCHES EXPECTED BY THE AFTERNOON ALONG THE CONTINUAL SOUTHERLY FLOW. SHEAR
AND INSTABILITY VALUES REMAIN MARGINAL...WITH THE THINKING THAT
HEAVY RAIN WILL BE THE MAIN THREAT WITH ANY SHOWERS AND
THUNDERSTORMS THAT FORM SUNDAY.
SHOWERS AND THUNDERSTORMS REMAIN LIKELY IN THE FORECAST FOR THE
FIRST PART OF THE WEEK WITH THE STATIONARY FRONT HUGGING THE
NORTHEAST AND MULTIPLE SHORTWAVES SQUEEZING BETWEEN THE UPPER LEVEL
TROUGH TO THE WEST AND THE RIDGE TO THE EAST. BY TUESDAY...THE
BERMUDA HIGH/UPPER LEVEL RIDGE NUDGES INTO THE
NORTHEAST...DIMINISHING THE THREAT FOR WIDESPREAD PRECIPITATION. THE
THREAT FOR THUNDERSTORMS BECOMES MORE DIURNAL AT THIS POINT WITH THE
PASSING SHORTWAVES COMBINED WITH DAY TIME HEATING BECOMING THE MAIN
TRIGGER RATHER THAN THE FRONTAL BOUNDARY. HAVE INCLUDED CHANCE POPS TO
ACCOUNT FOR THIS THROUGH THE END OF THE WEEK...WITH SOME DRYING
FINALLY EXPECTED BY FRIDAY AS THE RIDGE AND SURFACE HIGH TAKE MORE
CONTROL OF THE NORTHEAST AS THE UPPER LEVEL TROUGH FINALLY WEAKENS
AND PROGRESSES EAST.
TEMPS NEAR NORMAL FOR THE PERIOD...WITH HIGHS GENERALLY IN THE 80S
AND LOWS IN THE UPPER 60S TO LOWER 70S.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
LOW PRESSURE CURRENTLY MOVING AWAY FROM THE REGION TO THE NORTH. A
FRONTAL BOUNDARY STALLS OVER THE AREA TODAY.
BRIEF SHRA POSSIBLE ACROSS CITY AND INTERIOR TERMINALS LATE THIS
MORNING. MINIMAL IMPACT TO OPERATIONS EXPECTED.
SCT SHRA AND TSTMS POSSIBLE LATER WITH BETTER OVERALL CHANCES IN THE
LATE AFTERNOON INTO EVENING AND HAVE SHOWN THAT VIA TEMPO GROUP
EVERYWHERE EXCEPT ISP/GON.
GENERALLY VFR...EXCEPT FOR EASTERN TERMINALS...WHICH MAY SEE MVFR
CIGS THROUGHOUT THE DAY. MODERATE CONFIDENCE IN GUSTS DEVELOPING BY
16-17Z.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KEWR FCSTER COMMENTS: LOW-MODERATE CONFIDENCE IN COVERAGE OF TSTMS.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KJFK FCSTER COMMENTS: LOW-MODERATE CONFIDENCE IN COVERAGE OF TSTMS.
OCCASIONAL MVFR CEILINGS POSSIBLE THROUGH 19-20Z.
KLGA FCSTER COMMENTS: LOW-MODERATE CONFIDENCE IN COVERAGE OF TSTMS.
OCCASIONAL MVFR CEILINGS POSSIBLE THROUGH 18Z.
KTEB FCSTER COMMENTS: LOW-MODERATE CONFIDENCE IN COVERAGE OF TSTMS.
KHPN FCSTER COMMENTS: LOW-MODERATE CONFIDENCE IN COVERAGE OF TSTMS.
KISP FCSTER COMMENTS: OCCASIONAL MVFR CEILINGS POSSIBLE THROUGH 18Z.
.OUTLOOK FOR 15Z SAT THROUGH TUESDAY...
.SAT-TUE...SUB VFR POSSIBLE AT TIMES WITH PERIODS OF SHOWERS AND
TSTMS.
&&
.MARINE...
MINOR CHANGES MADE THIS UPDATE TO REFLECT THE LATEST CHANGES IN
OBSERVATIONS AND GUIDANCE. FORECAST APPEARS ON TRACK.
SCA REMAINS UP ON THE OCEAN WATERS INTO SATURDAY WITH SEAS AROUND
5 FT...AND POSSIBLE GUSTS UP TO 25 KTS.
SCA CONDITIONS EXPECTED ON THE OCEAN WATERS THROUGH THE WEEKEND WITH
SEAS BETWEEN 7 AND 9 FT. WIND GUSTS MAY TOUCH 25 KTS AS WELL DURING
THIS TIME. SEAS REMAIN ELEVATED DURING THE COMING WEEK WITH A
PERSISTENT SOUTHERLY FLOW CONTINUALLY BUILDING UP THE SEAS. WINDS
HOWEVER EXPECTED TO REMAIN BELOW SCA CRITERIA...SO ALL WATERS OTHER
THAN THE OCEAN SHOULD REMAIN SUB SCA.
WILL CONTINUE TO UNDERCUT WAVE WATCH III SEAS BY A FOOT OR SO.
&&
.HYDROLOGY...
CONFIDENCE IN FLASH FLOOD WATCH IS DECREASING. IF CURRENT
CONVECTIVE TRENDS HOLD...COULD CANCEL THIS AFTERNOON...BUT FOR NOW
WILL LEAVE UP FOR NYC/NE NJ/LOWER HUDSON VALLEY/SW CT.
SHOWERS AND THUNDERSTORMS SUNDAY INTO MONDAY MAY PRODUCE HEAVY
RAINFALL...WITH LOCALIZED FLOODING...ESPECIALLY OVER URBAN AND POOR
DRAINAGE AREAS. STILL TOO EARLY AT THIS TIME TO DETERMINE RAINFALL
TOTALS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND STREAMS...INCLUDING
OBSERVED AND FORECAST RIVER STAGES...PLEASE VISIT THE ADVANCED
HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...FLASH FLOOD WATCH UNTIL 9 PM EDT THIS EVENING FOR CTZ005-006-
009-010.
NY...FLASH FLOOD WATCH UNTIL 9 PM EDT THIS EVENING FOR NYZ067>075-
176>179.
NJ...FLASH FLOOD WATCH UNTIL 9 PM EDT THIS EVENING FOR NJZ002-004-
006-103>108.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR ANZ350-353-
355.
&&
$$
SYNOPSIS...GOODMAN/SEARS
NEAR TERM...MALOIT/GOODMAN
SHORT TERM...GOODMAN
LONG TERM...SEARS
AVIATION...BC/DH
MARINE...MALOIT/GOODMAN/SEARS
HYDROLOGY...MALOIT/GOODMAN/SEARS
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
330 PM EDT FRI JUN 28 2013
.DISCUSSION...
...SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS OVER THE WEEKEND
AND INTO EARLY NEXT WEEK...
CURRENT/TONIGHT...SCATTERED LIGHTNING STORMS WILL MOVE ENE MAINLY N
OF LAKE KISSIMMEE-CAPE CANAVERAL LINE THROUGH LATE AFTERNOON WITH
ADDITIONAL CONVECTIVE ACTIVITY FOR SRN BREVARD/SRN OSCEOLA AND
OKEECHOBEE COUNTY AND THE TREASURE COAST INTO THIS EVENING. LOW LVL
SW FLOW WILL HOLD OFF THE SEA BRZ NORTH OF SEBASTIAN INLET WITH SEA
BREEZE BOUNDARY JUST MAKING IT ONTO THE MAINLAND ALONG THE SRN
TREASURE COAST. WILL CONTINUE HIGHEST EVENING POPS NEAR THE COAST
AND SRN SECTIONS AND ONLY A SLIGHT CHANCE FOR LINGERING ACTIVITY
PAST 8 PM ACROSS THE NRN INTERIOR. HRRR MODEL INDICATES MUCH OF THE
ACTIVITY ACROSS NRN SECTIONS WILL MAKE IT INTO THE TREASURE COAST
DURING THE EARLY EVENING. COULD SEE A FEW STRONG EVENING STORMS WITH
STRONG WINDS...LOCALLY HEAVY RAIN AND FREQUENT LIGHTNING.
SAT-MON...A STORMY WEEKEND IS SHAPING UP EACH AFTERNOON AS DEEP AND
MOIST SW FLOW AHEAD OF AN MID LAYER TROUGH DIGGING FROM THE OHIO
VALLEY INTO THE SE STATES ALLOWS NUMEROUS SHOWERS AND STORMS TO MOVE
NORTHEAST EACH DAY WITH SOME ACTIVITY LINGERING INTO THE EVENING
HOURS. FOR SATURDAY...WILL SHOW HIGHEST POPS NORTH NEAR THE DEEPEST
MOISTURE ACROSS THE NRN PENINSULA AND ALSO ACROSS MARTIN COUNTY
WHERE DEEPER MOISTURE WILL MOVE UP FROM SOUTH FL. FOR SUNDAY AND
MONDAY WILL GO WITH LIKELY RAIN CHANCES EACH DAY (60 PCT) WITH
NUMEROUS SHOWERS AND STORMS EXPECTED. INCREASED CLOUD COVER IS
EXPECTED ESPEC SUNDAY INTO MONDAY. HIGHS WILL BE NEAR 90 TO THE
LOWER 90S. STEERING FLOW WILL BE FROM THE SW AT 15-20 KNOTS ON SAT
AND 20-25 KNOTS MAKING FOR FASTER NE STORM MOTION TOWARD THE COAST
AND NEAR SHORE ATLANTIC WATERS EACH DAY. STRONG STORMS OVER THE
WEEKEND MAY CONTAIN SMALL HAIL...FREQUENT LIGHTNING AND GUSTY WINDS
ESPECIALLY WITH THE STRONGER ENVIRONMENTAL FLOW. BOATERS AND
BEACHGOERS SHOULD CHECK THE RADAR AND FORECAST BEFORE HEADING TO THE
BEACH...INTRACOASTAL WATERS OR ATLC THIS WEEKEND INTO MONDAY.
TUE-THU...PREVIOUS EXTENDED DISCUSSION...
TROFFING PATTERN OVER THE ERN CONUS WILL DAMPEN OUT THRU THE MIDDLE
OF NEXT WEEK AS THE H30-H20 JET SHIFTS FROM A SLIGHT DIGGING TO A
FULL LIFTING ORIENTATION. ATLC RIDGE AXIS WILL RESPOND BY DRIFTING
BACK N INTO CENTRAL FL. THE RESULT WILL BE A WEAKENING STEERING FLOW
THAT WILL BACK TO THE S/SE...PROMOTING THE FORMATION OF THE EAST
COAST SEA BREEZE. INCREASING LOW/MID LVL SUPPRESSION AND WEAKENING
STEERING FLOW WILL DECREASE PRECIP COVERAGE BACK TO SCT COVERAGE.
NO SIG CHANGE IN AIRMASS...MAX TEMPS WITHIN A FEW DEGS OF CLIMO AVG
(L90S) AREAWIDE. DVLPG ONSHORE FLOW WILL KEEP MIN TEMPS ALONG THE
COAST BTWN 3-5F ABV AVG (M/U70S)...INTERIOR MIN TEMPS NEAR AVG
(L/M70S).
&&
.AVIATION...CONVECTIVE ACTIVITY AFFECTING NRN TERMINALS SHOULD
TRANSITION SOUTH THIS EVENING FROM KMLB-KVRB FROM 20Z-23Z AND
KFPR-KSUA FROM 21Z-24Z. MVFR CIGS WITH LCL IFR VSBYS WILL ACCOMPANY
TSRA THIS AFTN/EVENING. SCT/NMRS TSRA WILL AFFECT E CENTRAL FL
TERMINALS AGAIN ON SATURDAY...MAINLY AFT 18Z.
&&
.MARINE...
INCREASING SSW/SW WINDS OVER THE WEEKEND INTO MONDAY AND
THUNDERSTORMS MOVING FROM THE MAINLAND TO THE NEAR SHORE WATERS AND
OFFSHORE EACH DAY WILL KEEP THE WEATHER UNSETTLED FOR SMALL CRAFT
INTO EARLY NEXT WEEK. SSW WINDS WILL INCREASE TO 15-20 KNOTS
OFFSHORE THIS WEEKEND WITH SEAS TO 4-5 FT...LOWER NEAR THE IMMEDIATE
COAST. STORM COVERAGE MAY REMAIN HIGH INTO MONDAY BEFORE
TRANSITIONING TO SE FLOW BY WED/THU OF NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 76 91 75 90 / 30 60 50 60
MCO 74 92 74 91 / 20 60 50 60
MLB 75 91 77 89 / 30 50 40 60
VRB 75 91 76 89 / 30 50 40 60
LEE 76 92 76 91 / 20 60 50 60
SFB 76 92 76 92 / 20 60 50 60
ORL 76 92 76 92 / 20 60 50 60
FPR 75 91 75 90 / 30 40 30 60
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT-LONG TERM/AVIATION...VOLKMER
RADAR/IMPACT WX UPDATES....SEDLOCK
AREA FORECAST DISCUSSION
NWS MIAMI FL
222 PM EDT FRI JUN 28 2013
.SHORT TERM (TONIGHT THROUGH SUNDAY NIGHT)...
CURRENTLY, SOUTH FLORIDA CONTINUES TO BE MAINLY INFLUENCED BY THE
DEEP LAYER RIDGE WHICH STRETCHES ACROSS THE REGION INTO THE
ATLANTIC. THIS HAS RESULTED IN MAINTAINING A STEERING FLOW THAT IS
NEARLY NONEXISTENT WITH ERRATIC STORM MOTION. HOWEVER, AS THE DAY
PROGRESSES A MID LEVEL TROUGH WILL BE DEEPENING ACROSS THE EASTERN
U.S. WHICH IN TURN WILL SHIFT THE RIDGE BOTH ALOFT AND AT THE
SURFACE INTO THE FLORIDA STRAITS BY TONIGHT. HINTS OF THIS OCCURRING ARE
BECOMING EVIDENT IN THE RADAR AND SATELLITE SIGNATURES WITH A
VERY SLOW DRIFT TO THE NORTHEAST. THE HRRR IS COMING MORE IN LINE
WITH THAT THINKING ALSO. THE ONLY CONCERN IS THAT THE HRRR ALSO IS
SHOWING GOOD DEVELOPMENT BY 18Z WHICH HAS YET TO OCCUR SO TRENDED
LATER WITH THE HIGHER CHANCES OF CONVECTION.
GLOBAL MODELS CONTINUE WITH THE EVOLUTION OF THE TROUGH DEEPENING
IT THROUGH SUNDAY. AS THIS OCCURS, THE STEERING FLOW WILL BECOME
MORE SOUTHWEST ON SATURDAY WITH THE HIGHEST CHANCES FOR RAIN OVER
THE INTERIOR AND MOST OF THE EAST COAST METRO REGION. THE PRIMARY
THREAT WILL BE LOCALLY HEAVY RAINFALL POSSIBLE ALTHOUGH STORM
MOTION WILL PICK UP TO BETWEEN 5 AND 10 KNOTS AND RELATIVELY WEAK
MID LEVEL LAPSE RATES. THE MODELS ARE NOW SHOWING THE TROUGH
DEEPENING EVEN FURTHER ON SUNDAY WITH A BLOCKING PATTERN SETTING
UP ACROSS NORTH AMERICA AS MASSIVE RIDGES WILL BE IN EXISTENCE
OVER THE DESERT SOUTHWEST AND THE WESTERN ATLANTIC. THIS WILL ALSO
DEVELOP AN EVEN STRONGER DEEP SOUTHWEST STEERING FLOW. IN FACT,
FORECAST SOUNDINGS ARE SHOWING AROUND 20 KNOTS OF WIND IN THE LOW
LEVELS FROM ABOUT 2-7K FEET AND THIS ALONG WITH MID LEVEL LAPSE
RATES STILL NOT VERY IMPRESSIVE COULD LIMIT THE AMOUNT OF THUNDER.
THE KEY FACTOR WILL BE IF A EAST COAST SEA BREEZE WILL BE ABLE TO
DEVELOP WITH SUCH STRONG LOW LEVEL SOUTHWEST WINDS. THE PWAT IS
FORECAST TO BE WELL ABOVE TWO INCHES SO CHANCES FOR RAIN WILL
REMAIN HIGH BUT THERE COULD BE ONLY A FEW LIGHTNING STRIKES
ESPECIALLY WITH THE CONVECTION THAT DEVELOPS EARLY IN THE DAY. AT
THE SAME TIME HOWEVER, BOTH THE MAV AND MET GUIDANCE ARE SHOWING
VERY HIGH CHANCES FOR THUNDER. SO FOR THE TIME BEING WILL NOT
CHANGE THE FORECAST FOR SUNDAY AND WILL WAIT FOR FURTHER GUIDANCE
TO MAKE A DECISION ON WHETHER TO LOWER CHANCES FOR LIGHTNING
STRIKES. ALL IN ALL THOUGH, IT IS SHAPING UP TO BE A WET WEEKEND
FOR THE EAST COAST METRO REGION ESPECIALLY ON SUNDAY.
.LONG TERM (MONDAY THROUGH FRIDAY)...
THE BLOCKING PATTERN WILL CONTINUE INTO EARLY NEXT WEEK WITH A
VERY SLOW RETROGRESSION TO THE WEST IN THE OVERALL PATTERN BY THE
MIDDLE OF NEXT WEEK. THIS WILL RESULT IN THE DEEP LAYER RIDGE
EVER SO SLOWLY SHIFTING BACK TO THE NORTH. SO FOR TUESDAY,
FORECAST SOUNDINGS ARE INDICATING A STEERING FLOW MORE SOUTHERLY
AND THEN RETURNING TO A SOUTHEAST DIRECTION BY WEDNESDAY OR
THURSDAY. THE PWAT WILL REMAIN AT NEAR TWO INCHES ALL OF NEXT WEEK
SO THE CHANCES FOR RAIN WILL REMAIN HIGH BUT SHIFT BACK TO THE
INTERIOR AND SOUTHWEST COAST BY WEDNESDAY THROUGH FRIDAY.
&&
.AVIATION...
WITH THE WINDS SHIFTING MORE TO THE SOUTH, CONVECTIVE ACTIVITY HAS
BEEN MORE CHAOTIC. THE BERMUDA HIGH HAS WEAKENED, ALLOWING FOR
MORE INSTABILITY. HOWEVER, THIS HAS JUST LEAD TO MANY SMALL, WEAK
SHOWERS AND THUNDERSTORMS, RATHER THAN LARGE STRONG STORMS. GIVEN
THIS, HAVE REDUCED COVERAGE OF VCTS IN THE TAF SITES FROM KFLL
NORTH, ALTHOUGH, THEY MAY NEED TO BE ADDED BACK IN LATER TODAY.
WITH ACTIVITY PERSISTING FROM KOPF, SOUTH, HAVE KEPT THE VCTS IN,
AS WELL AS FOR KAPF. WINDS, DUE TO THE CONVECTION, HAVE ALSO BEEN
CHAOTIC TODAY. HOWEVER, THEY SHOULD BECOME SOUTHERLY AS CONVECTION
WANES ALONG THE COAST, WHICH APPEARS SOME SITES HAVE ALREADY BEGUN
THE SHIFT. TONIGHT, WINDS WILL BECOME LIGHT AND VARIABLE AND
CONVECTION SHOULD DIMINISH AFTER SUNSET. TOMORROW WILL SEE WINDS
BECOME MORE SOUTHWESTERLY AND ANOTHER ROUND OF CONVECTION WILL
BEGIN MID TO LATE MORNING.
&&
.MARINE...
THE WIND WILL BE MAINTAIN A SOUTH TO SOUTHWEST DIRECTION THROUGH
THE WEEKEND AND INTO EARLY NEXT WEEK. THE SEAS WILL BUILD SLIGHTLY
BY SUNDAY IN RESPONSE TO A TIGHTENING PRESSURE GRADIENT AND
INCREASE IN SPEED AS A STRONG TROUGH DEEPENS OVER THE EASTERN
STATES. A SCEC STATEMENT MAY BE NEEDED FOR A PORTION OF THE WATERS
AS SPEEDS COULD INCREASE IN THE RANGE OF 15 TO 20 KNOTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 76 89 77 89 / 50 50 30 70
FORT LAUDERDALE 75 88 79 89 / 50 50 40 70
MIAMI 77 90 78 90 / 40 40 40 70
NAPLES 75 91 76 91 / 20 40 30 70
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...30/KOB
AVIATION/RADAR...13/SI
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
433 PM EDT FRI JUN 28 2013
.SYNOPSIS...
A DEEPENING UPPER LEVEL TROUGH OVER THE EASTERN US...ALONG WITH
ABUNDANT MOISTURE...WILL PROVIDE ABOVE NORMAL CHANCES OF MAINLY
AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS THROUGH THE MIDDLE
OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
UPDATE: LATE AFTERNOON TEMPS IN THE LOW TO MID 90S. MODERATE TO
STRONG INSTABILITY ACROSS THE AREA THIS AFTERNOON. SOME SUBSIDENCE
STILL IN EFFECT...ALTHOUGH CUMULUS CLOUDS ARE DEVELOPING. LEE SIDE
SURFACE TROUGH TO DEVELOP. BASED ON CURRENT 88D REGIONAL RADAR
TRENDS...EXPECT LATE AFTERNOON CONVECTION EXPECTED TO DEVELOP AND
CONTINUE TONIGHT. CONVECTION STRETCHING FROM CENTRAL VIRGINIA
ACROSS THE PIEDMONT OF NC INTO THE MTS. ADDITIONAL CONVECTION ACROSS
GA DEVELOPING...ESPECIALLY ACROSS CNTRL AND SOUTHERN GA. SOME OF
THESE STORMS COULD BE STRONG AS THEY MOVE INTO THE MIDLANDS AND
CSRA BY EARLY EVENING AND UP THROUGH MIDNIGHT. EXPECT ANOTHER
MUGGY NIGHT AS TEMPERATURES ONLY FALL INTO THE LOWER/MIDDLE 70S
WITH DEWPOINTS TEMPERATURES NEAR/ARND 70.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY/...
UPPER LEVEL TROF TO DEEPEN OVER THE AREA DURING THE WEEKEND. THE
SURFACE FRONT AND A COUPLE OF UPPER LEVEL SHORT WAVES WILL PROVIDE
A FOCUS FOR SHOWERS AND THUNDERSTORMS. DEEP SOUTHWEST FLOW ALOFT
WILL TRANSPORT MOISTURE/SEVERAL SHORT WAVE TRIGGERS AND MODERATELY
UNSTABLE AIR MASS SUPPORTS SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS THROUGH THE WEEKEND...MAINLY DIURNAL.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
UPPER LEVEL TROF REMAINS OVER THE AREA THROUGH MUCH OF THE WEEK.
THIS WILL CONTINUE THE PATTERN OF AFTERNOON/EVENING SHOWERS AND
THUNDERSTORMS. HOWEVER... BY THURSDAY THE TROF BEGINS TO LIFT OUT
AND HIGH PRESSURE BEGINS TO BUILD IN FROM THE MID ATLANTIC AREA
REDUCING THE CHANGE OF RAIN LATE IN THE WEEK AND INTO NEXT
WEEKEND. TEMPS WILL IN THE UPPER 80S TO LOWER 90S DURING THE DAY
AND IN THE LOWER 70S AT NIGHT.
&&
.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
VFR CONDITIONS THROUGH LATE THIS AFTERNOON. WEST TO SOUTHWEST
WINDS PROVIDING DOWNSLOPE FLOW/SUBSIDENCE. CLOUD BASES AROUND 4000
FEET WITH CIRRUS CLOUDS ABOVE.
SHOWERS AND THUNDERSTORMS EXPECTED TO TO DEVELOP LATE THIS AFTERNOON
AND EVENING AS AN UPPER LEVEL DISTURBANCE CROSSES THE REGION.
OPTIMUM PERIOD FOR CONVECTION FROM 28/23Z TO 29/06Z. HAVE INCLUDED
TEMPO GROUP IN TAFS FOR EVENING CONVECTION. THE NAM AND RUC MODELS ARE
INDICATING IFR/MVFR CIGS DEVELOPING LATE TONIGHT INTO SATURDAY
MORNING. SINCE CONFIDENCE IS LOW...HAVE NOT INCLUDED EARLY MORNING
RESTRICTIONS. THE CHANCE FOR SCATTERED CONVECTION WILL CONTINUE
ACROSS THE TAF SITES SATURDAY MORNING INTO THE AFTERNOON.
EXTENDED AVIATION OUTLOOK...CIG/VSBY RESTRICTIONS POSSIBLE EACH DAY
IN MAINLY AFTERNOON/EVENING THUNDERSTORMS...AS WELL AS LATE
NIGHT/EARLY MORNING FOG/STRATUS.
&&
.CLIMATE...
THROUGH THU JUNE 28TH...AUGUSTA GA BUSH FIELD HAS RECEIVED A
TOTAL OF 10.52 INCHES OF RAIN SO FAR FOR THE MONTH OF JUNE. THIS
HAS ALREADY ESTABLISHED JUNE 2013 AS THE 2ND WETTEST JUNE ON
RECORD AT AUGUSTA. THE WETTEST JUNE ON RECORD AT AUGUSTA IS 10.59
INCHES SET IN 2004...SO TO ESTABLISH JUNE 2013 AS THE WETTEST JUNE
ON RECORD AT AUGUSTA...AGS NEEDS TO RECEIVE 0.08 MORE INCHES OF
RAIN THIS MONTH. ALTHOUGH WE DO NOT KEEP RECORDS FOR DANIEL
FIELD...IT HAS RECEIVED 13.47 INCHES OF RAIN SO FAR FOR JUNE.
QUITE A DRAMATIC DIFFERENCE FROM LAST JUNE AS AUGUSTA BUSH FIELD
ONLY RECEIVED 2.48 INCHES FOR THE MONTH.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
77
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
156 PM EDT FRI JUN 28 2013
.SYNOPSIS...
A DEEPENING UPPER LEVEL TROUGH OVER THE EASTERN US...ALONG WITH
ABUNDANT MOISTURE...WILL PROVIDE ABOVE NORMAL CHANCES OF MAINLY
AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS THROUGH THE MIDDLE
OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE: EARLY AFTERNOON TEMPS IN THE LOW TO MID 90S. MODERATE TO
STRONG INSTABILITY ACROSS THE AREA THIS AFTERNOON. SUBSIDENCE
STILL IN EFFECT...ALTHOUGH CUMULUS CLOUDS ARE DEVELOPING.
LEE SIDE SURFACE TROUGH TO DEVELOP. LATE AFTERNOON CONVECTION
EXPECTED TO DEVELOP AND CONTINUE TONIGHT.
PREVIOUS DISCUSSION:
UPPER LEVEL RIDGE WILL CONTINUE BUILDING OVER THE WESTERN CONUS...
WHILE CLOSED UPPER LOW CONTINUES TO SPIN OVER THE GREAT
LAKES/MIDWEST...RESULTING IN A DEEPENING UPPER TROUGH OVER THE
SOUTHEASTERN CONUS. MODELS CONTINUE TO INDICATE SOME DRIER AIR
ENTERING OUR REGION EARLY TODAY...BUT MAINTAIN INDICATIONS OF AN
UPPER DISTURBANCE AND BATCH OF CONVECTION SETTING UP TO OUR WEST
AND NORTHWEST WHICH DRIFTS INTO THE MIDLANDS AND CSRA THIS EVENING.
NOT MUCH CONVECTION EXPECTED BEFORE 21Z THOUGH...WITH TRIGGER
LACKING/HIGH LFC...BUT AIR MASS SHOULD BECOME INCREASINGLY UNSTABLE.
SO EXPECT MODERATE TO STRONG INSTABILITY AND HIGHEST PRECIPITABLE
WATER ACROSS THE EAST MIDLANDS LATE. WITH LOW LEVEL CONVERGENCE
ASSOCIATED WITH SURFACE TROUGH ACROSS MIDLANDS THIS EVENING
AND SUPPORT FOR NUMEROUS SHOWERS/THUNDERSTORMS FROM LOCAL
WRF/SREF/SPC WRF...WENT WITH HIGH CHANCE TO LIKELY POPS.
SHEAR APPEARS WEAKER THAN YESTERDAY BUT A FEW STORMS MAY BECOME
SEVERE WITH DAMAGING WIND MAIN THREAT. HEAVY RAIN THREAT CONTINUES
WITH HIGH PRECIPITABLE WATER. TEMPERATURES SHOULD BE WARMER THAN
YESTERDAY DUE TO WARM ADVECTION/MORE INSOLATION.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
UPPER LEVEL TROF TO DEEPEN OVER THE AREA DURING THE WEEKEND. THE
SURFACE FRONT AND A COUPLE OF UPPER LEVEL SHORT WAVES WILL PROVIDE
A FOCUS FOR SHOWERS AND THUNDERSTORMS. DEEP SOUTHWEST FLOW ALOFT
WILL TRANSPORT MOISTURE/SEVERAL SHORT WAVE TRIGGERS AND MODERATELY
UNSTABLE AIR MASS SUPPORTS SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS THROUGH THE WEEKEND...MAINLY DIURNAL.
&&
.LONG TERM / MONDAY THROUGH FRIDAY/... UPPER LEVEL TROF REMAINS
OVER THE AREA THROUGH MUCH OF THE WEEK. THIS WILL CONTINUE THE
PATTERN OF AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS. HOWEVER...
BY THURSDAY THE TROF BEGINS TO LIFT OUT AND HIGH PRESSURE BEGINS
TO BUILD IN FROM THE MID ATLANTIC AREA REDUCING THE CHANGE OF RAIN
LATE IN THE WEEK AND INTO NEXT WEEKEND. TEMPS WILL IN THE UPPER
80S TO LOWER 90S DURING THE DAY AND IN THE LOWER 70S AT NIGHT.
&&
.AVIATION /18Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS THROUGH THIS AFTERNOON. WEST TO SOUTHWEST WINDS
PROVIDING DOWNSLOPE FLOW/SUBSIDENCE. CLOUD BASES AROUND 4000 FEET
WITH CIRRUS CLOUDS ABOVE.
SHOWERS AND THUNDERSTORMS EXPECTED TO TO DEVELOP LATE THIS AFTERNOON
AND EVENING AS AN UPPER LEVEL DISTURBANCE CROSSES THE REGION.
OPTIMUM PERIOD FOR CONVECTION FROM 28/23Z TO 29/06Z. HAVE INCLUDED
TEMPO GROUP IN TAFS FOR EVENING CONVECTION. THE NAM AND RUC MODELS ARE
INDICATING IFR/MVFR CIGS DEVELOPING LATE TONIGHT INTO SATURDAY
MORNING. SINCE CONFIDENCE IS LOW...HAVE NOT INCLUDED EARLY MORNING
RESTRICTIONS. THE CHANCE FOR SCATTERED CONVECTION WILL CONTINUE
ACROSS THE TAF SITES SATURDAY MORNING INTO THE AFTERNOON.
EXTENDED AVIATION OUTLOOK...CIG/VSBY RESTRICTIONS POSSIBLE EACH DAY
IN MAINLY AFTERNOON/EVENING THUNDERSTORMS...AS WELL AS LATE
NIGHT/EARLY MORNING FOG/STRATUS.
&&
.CLIMATE...
THROUGH THU JUNE 27TH...AUGUSTA GA BUSH FIELD HAS RECEIVED A
TOTAL OF 10.52 INCHES OF RAIN SO FAR FOR THE MONTH OF JUNE. THIS
HAS ALREADY ESTABLISHED JUNE 2013 AS THE 2ND WETTEST JUNE ON
RECORD AT AUGUSTA. THE WETTEST JUNE ON RECORD AT AUGUSTA IS 10.59
INCHES SET IN 2004...SO TO ESTABLISH JUNE 2013 AS THE WETTEST JUNE
ON RECORD AT AUGUSTA...AGS NEEDS TO RECEIVE 0.08 MORE INCHES OF
RAIN THIS MONTH.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
309 PM CDT FRI JUN 28 2013
.MESOSCALE DISCUSSION...
230 PM CDT
MONITORING GUSTY STORMS ACROSS NORTH CENTRAL TO NORTHEAST IL. A
COUPLE ARCS OF CONVECTION HAVE DEVELOPED ON THE LEADING EDGE OF
THE INCOMING SHORT WAVE. THIS LEADING EDGE HAS AN UNSTABLE
ATMOSPHERE TO WORK WITH GIVEN SURFACE TEMPERATURES SEVERAL
DEGREES ABOVE CONVECTIVE TEMPS PER MORNING SOUNDINGS AND AMDAR
DATA. NICE INVERTED-V SHAPE SOUNDINGS ARE PRESENT UP TO 5000-6000
FT WITH ASSOCIATED DOWNDRAFT CAPE ANALYZED BY THE RAP IN EXCESS OF
800 J/KG. THE STORM MOVING ACROSS SOUTHERN KANE NOW HAS PRODUCED A
46 MPH GUST AT DEKALB...AN ESTIMATED 50 MPH GUST AT HINKLEY...AND
A MEASURED 52 MPH GUST AT AURORA. THIS IS THE MOST ORGANIZED
STORM BUT ANY OF THESE WILL HAVE THE POTENTIAL TO PRODUCE
WINDS...AND POSSIBLY SOME SMALL HAIL. WILL CONTINUE WITH SPECIAL
WEATHER STATEMENTS ON THESE BUT WOULD NOT BE SURPRISED TO HAVE A
BRIEF SEVERE THUNDERSTORM WARNING OR TWO...ESPECIALLY ON THESE
LEADING TWO ARCS.
MTF
&&
.DISCUSSION...
1135 AM CDT
ONLY SOME MINOR TWEAKS TO SHORT TERM FORECAST GRIDS FOR THE REST
OF TODAY AND THIS EVENING TO ACCOUNT FOR RECENT AND CURRENT
TEMPERATURE...DEW POINT AND CLOUD TRENDS.
A SMALL VORT MAX IN THE NW UPPER FLOW DROPPED SE TO SE WI
OVERNIGHT PRODUCING SOME MINOR SHOWERS AND AN ISOLATED TS. BUT MID
MORNING IT HAD MOVES OUT OF SOUTHERN LAKE MI AND IS CURRENTLY
UPPER APPROACHING THE SW SHORE OF LOWER MI AND WILL NOT POSE ANY
THREAT OF SHRA OR TS TO THE LOCAL AREA.
UPSTREAM...WATER VAPOR SATELLITE LOOPS SHOW ANOTHER SHORT
WAVE/VORT MAX HAS BEEN QUICKLY DROPPING SSE FROM E CENTRAL MN TO
W CENTRAL WI THIS MORNING. NAM12 AND RUC13 SEEM TO HAVE A DECENT
HANDLE ON THIS FEATURE AND TURN IT MORE SE AS IT STARTS TO ENTER
THE BROAD UPPER TROUGH FROM THE UPPER MIDWEST E TO THE NEW
ENGLAND COAST AND S TO THE MID MS...OH...AND TN VALLEYS...AND THE
MID ATLANTIC COAST.
EXTRAPOLATION OF RECENT MOVEMENT OF THE WI SHORT WAVE IS IN DECENT
AGREEMENT WITH ABOVE MENTIONED MODELS BRINGING THE THE SHORT WAVE
TROUGH S OF THE WI BORDER BETWEEN 20 AND 21Z. SIGNIFICANT MID
LEVEL COOLING OCCUR ED SINCE YESTERDAY AND WHILE MODELS TEMPERATURE
PROFILES SHOW WARMING DURING THE DAY BY 29.00Z THERE IS STILL A
DEEP ALBEIT MUCH NARROW AREA OF CAPE OVER THE LOCAL AREA THAN THIS
MORNING. STILL...WITH CONVECTIVE TEMPERATURES TO BE REACHED BY
NOON EXPECT TO SEE QUICK CU DEVELOPMENT AHEAD OF LARGE AREA OF
CLOUDS ADVECTING ACROSS SOUTHERN WI TOWARD NORTHERN IL AND NW IN.
AS OF 1125 AM CDT RADAR COMPOSITE LOOP SHOWED ONLY SCATTERED SMALL
LIGHT SHOWERS UPSTREAM OF THE LOCAL FORECAST AREA BUT WITH SOME
ADDITIONAL HEATING AVAILABLE THROUGH DECREASING ML-CAPE OF 1200
TO 2000 J/KG DEPENDING ON WHICH MODEL OVER THE AREA AND DECENT UVV
IN THE LOWER AND MID LEVELS AHEAD OF THE APPROACHING SHORT WAVE
TROUGH FEEL THAT ALONG WITH INCREASING CLOUDY COVER TO BROKEN OR
NEAR OVERCAST PROBABILITY OF SHOWERS WILL BE INCREASING TO LIKELY
DURING THE AFTERNOON...WITH ALSO A SOME THUNDERSTORMS OCCURRING.
TRS
//PREV DISCUSSION...
339 AM CDT
SYNOPSIS...THE LARGE SCALE PATTERN WILL NOT CHANGE MUCH OVER THE
NEXT WEEK WITH A LARGE RIDGE OVER THE WESTERN U.S. AND A TROUGH OVER
THE EASTERN U.S. STORMS ARE EXPECTED TODAY AND TOMORROW WITH A BRIEF
DRY PERIOD EXPECTED EARLY NEXT WEEK. ALSO EXPECTED IS A COOL PERIOD
AS NORTH FLOW SETS UP SATURDAY.
TODAY AND TONIGHT...
THE SURFACE LOW THAT IS CENTERED OVER NEW ENGLAND AND STRETCHES BACK
TO LAKE SUPERIOR WILL SINK SOUTH TODAY. IN ADDITION THE UPPER LEVEL
JET EXIT WILL ALSO BE SINKING SOUTH THROUGH THE CWA WITH THE LEFT
JET EXIT REGION OVERHEAD DURING PRIME HEATING THIS AFTERNOON. LONG
SKINNY CAPE OF UP TO 1000 J/KG IS FORECAST AND SHEAR WILL BE MINIMAL
AT BEST...10 KT OR SO. THEREFORE EXPECTING SCATTERED STORMS TO
SPROUT FIRST ALONG THE IL/WI STATE LINE AROUND NOON AND SCATTERED
THUNDERSTORMS SHOULD SPREAD ACROSS THE CWA EARLY THIS AFTERNOON.
LATER IN THE AFTERNOON AS THE WAVE COMES THROUGH EXPECTING THE MAIN
THUNDERSTORM ACTIVITY TO BE EAST OF A NORTHWEST BOONE COUNTY TO
SOUTH CENTRAL IROQUOIS COUNTY LINE. SCATTERED THUNDERSTORMS ARE
CERTAINLY POSSIBLE WEST OF THAT LINE AS WELL...BUT THINKING THE
STRONGER STORMS AND BETTER COVERAGE WILL BE EAST OF THE LINE.
STORMS WILL LIKELY BE PULSEY AND UNORGANIZED AS THERE IS A DECENT
AMOUNT OF CAPE BUT NOT ENOUGH SHEAR FOR LONG LIVED ORGANIZED STORMS.
THE DIURNAL CONVECTION WILL WIND DOWN AFTER SUNSET WITH SCATTERED
SHOWERS OVERNIGHT. ENJOY THE TEMPS TODAY BECAUSE A COOL DOWN IS
EXPECTED TOMORROW. HIGHS WILL RANGE FROM AROUND 80 TO THE MID 80S.
SATURDAY AND SUNDAY...
WINDS TURN NORTH SATURDAY BEHIND THE UPPER LEVEL TROUGH AND MUCH
COOLER AIR MOVES INTO THE REGION. THE UPPER LEVEL TROUGH SPLITS
WITH THE SOUTHERN LOW BECOMING A CLOSED LOW OVER OHIO LATE SATURDAY
NIGHT. YET ANOTHER UPPER LEVEL DISTURBANCE PASSES OVER THE WESTERN
HALF OF THE CWA SPARKING ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS
PRIMARILY WEST OF THE CHICAGO METRO. CAPE WILL BE VERY LOW ON
SATURDAY WITH MAYBE A FEW HUNDRED J/KG AVAILABLE. SHEAR WILL BE A
BIT MORE FAVORABLE FOR ORGANIZED CONVECTION...BUT THINKING GENERAL
THUNDERSTORMS WILL BE THE MAIN SHOW.
THE DIURNAL SHOWERS AND THUNDERSTORMS DISSIPATE OVERNIGHT WITH LOW
TEMPS FALLING INTO THE UPPER 50S. CLOUD COVER SHOULD REMAIN THICK
ENOUGH TO KEEP TEMPS UP A BIT.
ON SUNDAY THE UPPER LEVEL TROUGH RETROGRADES A BIT ACROSS THE OHIO
RIVER VALLEY AND INSTABILITY ASSOCIATED WITH THE LOW MAY HELP A FEW
SHOWERS AND THUNDERSTORMS FORM ON SUNDAY. AREAS ALONG AND SOUTH OF
I-80 HAVE THE BEST CHANCE FOR A PASSING SHOWER OR THUNDERSTORM.
COVERAGE SHOULD REMAIN SPARSE AND A RAIN OUT IS NOT EXPECTED.
ANOTHER DRY NIGHT IS EXPECTED SUNDAY NIGHT. SUNDAY LOOKS A BIT
WARMER WITH HIGHS IN THE MID 70S BUT CLOUDS SHOULD THIN SUNDAY NIGHT
SO WENT A FEW DEGREES COOLER SUNDAY NIGHT.
EXTENDED...MONDAY THROUGH THURSDAY...
THE LARGE LOW PRESSURE REMAINS OVER THE EAST COAST WHILE HIGH
PRESSURE SINKS SOUTH OUT OF CANADA REACHING THE CWA ON MONDAY. THE
UPPER LEVEL TROUGH WILL REMAIN OVERHEAD THROUGHOUT THE EXTENDED WITH
DISTURBANCES ROTATING AROUND IT. AS SUCH LEFT PERIODIC CHANCES OF
SHOWERS AND THUNDERSTORMS IN THE FORECAST. TEMPS REMAIN BELOW
NORMAL THANKS TO THE UPPER LEVEL LOW AND NORTHERLY SURFACE FLOW.
HOWEVER LOOKING LIKE WE MIGHT SEE HIGHS IN THE 80S BY LATE NEXT
WEEK.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* PERIODS OF SHRA WITH ISOLATED TSRA THROUGH 22Z. SOME STORMS MAY
HAVE GUSTS IN EXCESS OF 40 MPH.
* MVFR CIGS ARRIVING THIS EVENING WITH A GOOD CHANCE...ESPECIALLY
FOR LATE JUNE...FOR IFR LATER TONIGHT INTO SAT MORNING.
* NORTHWEST WINDS TURN NORTH LATE THIS EVENING/OVERNIGHT.
* CHANCE FOR SHRA ON SAT AFTERNOON.
//DISCUSSION...UPDATED 18Z...
BROAD LOW PRESSURE ACROSS THE EASTERN GREAT LAKES AND NEW ENGLAND
WILL CONTINUE TO PRESENT NORTHERLY FLOW OVER THE TAF SITES INTO
THIS WEEKEND. AN UPPER LEVEL DISTURBANCE MOVING OVERHEAD THIS
AFTERNOON INTO THE EARLY EVE WILL PRESENT THE GREATEST COVERAGE OF
SHOWERS THROUGH THE NEXT 24 HOURS...WITH ISOLATED TO SCATTERED
THUNDER LIKELY. SOME OF THESE INDIVIDUAL STORMS/SHOWERS COULD BE
GUSTY GIVEN THE ENVIRONMENT...PUTTING OUT GUST FRONTS THAT WILL
EXTEND A WAYS FROM THE ACTUAL RAIN. COVERAGE IS ANTICIPATED TO BE
AROUND 70 PERCENT ACROSS CHICAGOLAND FROM 20Z-23Z. COVERAGE WILL
BE SLOW TO WANE THROUGH 02Z-04Z THOUGH DIMINISHING INSTABILITY
SHOULD ALLOW THE THUNDER THREAT TO DROP QUICKLY THIS EVE. NW WINDS
WILL TURN NNE AT SOME POINT TONIGHT...THOUGH CONFIDENCE IN EXACT
TIMING REMAINS LOW. WINDS LOOK TO BE NNE TO NE ON SAT...AT LEAST
BY LATE MORNING INTO THE AFTERNOON WITH HIGHER CONFIDENCE.
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE IN SHRA WITH MEDIUM CONFIDENCE IN TSRA. HIGH
CONFIDENCE IN DURATION OF SHRA AND TSRA...ALTHOUGH TIMES OF
SHRA/TSRA AT THE AIRFIELD MAY BE BRIEF.
* HIGH CONFIDENCE IN MVFR ARRIVING AT SOME POINT THIS EVE AND
MEDIUM CONFIDENCE IN IFR. LOW CONFIDENCE IN IFR DURATION.
* MEDIUM CONFIDENCE IN WIND DIRECTION AND SPEED. WINDS MAY TURN
SHARPLY NEAR OUTFLOW BOUNDARIES FROM SHOWERS THIS AFTERNOON.
* LOW CONFIDENCE IN SCT SHRA SAT AFTERNOON.
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT THROUGH SUNDAY...VFR.
MONDAY...VFR. CHANCE FOR SHOWERS MONDAY EVENING.
TUESDAY THROUGH THURSDAY...DRY AND VFR.
MTF
&&
.MARINE...
305 PM CDT
A SPRAWLING AREA OF LOW PRESSURE OVER NEW YORK AND THE EASTERN
GREAT LAKES WILL SLOWLY TRACK NORTHEAST INTO SOUTHERN QUEBEC BY
TOMORROW AFTERNOON. A TROUGH OF LOW PRESSURE EXTENDING WEST FROM
THIS LOW THROUGH CENTRAL LAKE MICHIGAN WILL PUSH SOUTH ACROSS THE
LAKE...USHERING IN COOLER AIR AND STRONGER WINDS OVER LAKE
MICHIGAN. IN GENERAL...WINDS SHOULD BE A LITTLE STRONGER OVER THE
SOUTHERN PORTIONS OF THE LAKE WHERE THE PRESSURE GRADIENT WILL BE
STRONGEST..TO 25KT...THOUGH THERE SHOULD BE PERIODS WHEN WINDS
WILL DECREASE TO 10 TO 20 KT. WINDS WILL TURN NORTHERLY BEHIND THE
TROUGH PASSAGE...AND REMAIN GENERALLY NORTHERLY THROUGH MONDAY
NIGHT AS HIGH PRESSURE BUILDS ACROSS THE NORTHERN PLAINS TO THE
UPPER MISSISSIPPI VALLEY. THE HIGH WILL MOVE ACROSS WESTERN GREAT
LAKES REGION ON TUESDAY...BRINGING SOME LIGHTER WINDS BEFORE
TURNING MORE SOUTHERLY BY MIDWEEK AS THE HIGH SLIDES OFF TO THE
EAST.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...BEACH HAZARDS STATEMENT...ILZ006-ILZ014...4 PM SATURDAY TO 3 AM
MONDAY.
IN...BEACH HAZARDS STATEMENT...INZ001-INZ002...9 AM SATURDAY TO 3 AM
MONDAY.
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
258 PM CDT FRI JUN 28 2013
.MESOSCALE DISCUSSION...
230 PM CDT
MONITORING GUSTY STORMS ACROSS NORTH CENTRAL TO NORTHEAST IL. A
COUPLE ARCS OF CONVECTION HAVE DEVELOPED ON THE LEADING EDGE OF
THE INCOMING SHORT WAVE. THIS LEADING EDGE HAS AN UNSTABLE
ATMOSPHERE TO WORK WITH GIVEN SURFACE TEMPERATURES SEVERAL
DEGREES ABOVE CONVECTIVE TEMPS PER MORNING SOUNDINGS AND AMDAR
DATA. NICE INVERTED-V SHAPE SOUNDINGS ARE PRESENT UP TO 5000-6000
FT WITH ASSOCIATED DOWNDRAFT CAPE ANALYZED BY THE RAP IN EXCESS OF
800 J/KG. THE STORM MOVING ACROSS SOUTHERN KANE NOW HAS PRODUCED A
46 MPH GUST AT DEKALB...AN ESTIMATED 50 MPH GUST AT HINKLEY...AND
A MEASURED 52 MPH GUST AT AURORA. THIS IS THE MOST ORGANIZED
STORM BUT ANY OF THESE WILL HAVE THE POTENTIAL TO PRODUCE
WINDS...AND POSSIBLY SOME SMALL HAIL. WILL CONTINUE WITH SPECIAL
WEATHER STATEMENTS ON THESE BUT WOULD NOT BE SURPRISED TO HAVE A
BRIEF SEVERE THUNDERSTORM WARNING OR TWO...ESPECIALLY ON THESE
LEADING TWO ARCS.
MTF
&&
.DISCUSSION...
1135 AM CDT
ONLY SOME MINOR TWEAKS TO SHORT TERM FORECAST GRIDS FOR THE REST
OF TODAY AND THIS EVENING TO ACCOUNT FOR RECENT AND CURRENT
TEMPERATURE...DEW POINT AND CLOUD TRENDS.
A SMALL VORT MAX IN THE NW UPPER FLOW DROPPED SE TO SE WI
OVERNIGHT PRODUCING SOME MINOR SHOWERS AND AN ISOLATED TS. BUT MID
MORNING IT HAD MOVES OUT OF SOUTHERN LAKE MI AND IS CURRENTLY
UPPER APPROACHING THE SW SHORE OF LOWER MI AND WILL NOT POSE ANY
THREAT OF SHRA OR TS TO THE LOCAL AREA.
UPSTREAM...WATER VAPOR SATELLITE LOOPS SHOW ANOTHER SHORT
WAVE/VORT MAX HAS BEEN QUICKLY DROPPING SSE FROM E CENTRAL MN TO
W CENTRAL WI THIS MORNING. NAM12 AND RUC13 SEEM TO HAVE A DECENT
HANDLE ON THIS FEATURE AND TURN IT MORE SE AS IT STARTS TO ENTER
THE BROAD UPPER TROUGH FROM THE UPPER MIDWEST E TO THE NEW
ENGLAND COAST AND S TO THE MID MS...OH...AND TN VALLEYS...AND THE
MID ATLANTIC COAST.
EXTRAPOLATION OF RECENT MOVEMENT OF THE WI SHORT WAVE IS IN DECENT
AGREEMENT WITH ABOVE MENTIONED MODELS BRINGING THE THE SHORT WAVE
TROUGH S OF THE WI BORDER BETWEEN 20 AND 21Z. SIGNIFICANT MID
LEVEL COOLING OCCUR ED SINCE YESTERDAY AND WHILE MODELS TEMPERATURE
PROFILES SHOW WARMING DURING THE DAY BY 29.00Z THERE IS STILL A
DEEP ALBEIT MUCH NARROW AREA OF CAPE OVER THE LOCAL AREA THAN THIS
MORNING. STILL...WITH CONVECTIVE TEMPERATURES TO BE REACHED BY
NOON EXPECT TO SEE QUICK CU DEVELOPMENT AHEAD OF LARGE AREA OF
CLOUDS ADVECTING ACROSS SOUTHERN WI TOWARD NORTHERN IL AND NW IN.
AS OF 1125 AM CDT RADAR COMPOSITE LOOP SHOWED ONLY SCATTERED SMALL
LIGHT SHOWERS UPSTREAM OF THE LOCAL FORECAST AREA BUT WITH SOME
ADDITIONAL HEATING AVAILABLE THROUGH DECREASING ML-CAPE OF 1200
TO 2000 J/KG DEPENDING ON WHICH MODEL OVER THE AREA AND DECENT UVV
IN THE LOWER AND MID LEVELS AHEAD OF THE APPROACHING SHORT WAVE
TROUGH FEEL THAT ALONG WITH INCREASING CLOUDY COVER TO BROKEN OR
NEAR OVERCAST PROBABILITY OF SHOWERS WILL BE INCREASING TO LIKELY
DURING THE AFTERNOON...WITH ALSO A SOME THUNDERSTORMS OCCURRING.
TRS
//PREV DISCUSSION...
339 AM CDT
SYNOPSIS...THE LARGE SCALE PATTERN WILL NOT CHANGE MUCH OVER THE
NEXT WEEK WITH A LARGE RIDGE OVER THE WESTERN U.S. AND A TROUGH OVER
THE EASTERN U.S. STORMS ARE EXPECTED TODAY AND TOMORROW WITH A BRIEF
DRY PERIOD EXPECTED EARLY NEXT WEEK. ALSO EXPECTED IS A COOL PERIOD
AS NORTH FLOW SETS UP SATURDAY.
TODAY AND TONIGHT...
THE SURFACE LOW THAT IS CENTERED OVER NEW ENGLAND AND STRETCHES BACK
TO LAKE SUPERIOR WILL SINK SOUTH TODAY. IN ADDITION THE UPPER LEVEL
JET EXIT WILL ALSO BE SINKING SOUTH THROUGH THE CWA WITH THE LEFT
JET EXIT REGION OVERHEAD DURING PRIME HEATING THIS AFTERNOON. LONG
SKINNY CAPE OF UP TO 1000 J/KG IS FORECAST AND SHEAR WILL BE MINIMAL
AT BEST...10 KT OR SO. THEREFORE EXPECTING SCATTERED STORMS TO
SPROUT FIRST ALONG THE IL/WI STATE LINE AROUND NOON AND SCATTERED
THUNDERSTORMS SHOULD SPREAD ACROSS THE CWA EARLY THIS AFTERNOON.
LATER IN THE AFTERNOON AS THE WAVE COMES THROUGH EXPECTING THE MAIN
THUNDERSTORM ACTIVITY TO BE EAST OF A NORTHWEST BOONE COUNTY TO
SOUTH CENTRAL IROQUOIS COUNTY LINE. SCATTERED THUNDERSTORMS ARE
CERTAINLY POSSIBLE WEST OF THAT LINE AS WELL...BUT THINKING THE
STRONGER STORMS AND BETTER COVERAGE WILL BE EAST OF THE LINE.
STORMS WILL LIKELY BE PULSEY AND UNORGANIZED AS THERE IS A DECENT
AMOUNT OF CAPE BUT NOT ENOUGH SHEAR FOR LONG LIVED ORGANIZED STORMS.
THE DIURNAL CONVECTION WILL WIND DOWN AFTER SUNSET WITH SCATTERED
SHOWERS OVERNIGHT. ENJOY THE TEMPS TODAY BECAUSE A COOL DOWN IS
EXPECTED TOMORROW. HIGHS WILL RANGE FROM AROUND 80 TO THE MID 80S.
SATURDAY AND SUNDAY...
WINDS TURN NORTH SATURDAY BEHIND THE UPPER LEVEL TROUGH AND MUCH
COOLER AIR MOVES INTO THE REGION. THE UPPER LEVEL TROUGH SPLITS
WITH THE SOUTHERN LOW BECOMING A CLOSED LOW OVER OHIO LATE SATURDAY
NIGHT. YET ANOTHER UPPER LEVEL DISTURBANCE PASSES OVER THE WESTERN
HALF OF THE CWA SPARKING ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS
PRIMARILY WEST OF THE CHICAGO METRO. CAPE WILL BE VERY LOW ON
SATURDAY WITH MAYBE A FEW HUNDRED J/KG AVAILABLE. SHEAR WILL BE A
BIT MORE FAVORABLE FOR ORGANIZED CONVECTION...BUT THINKING GENERAL
THUNDERSTORMS WILL BE THE MAIN SHOW.
THE DIURNAL SHOWERS AND THUNDERSTORMS DISSIPATE OVERNIGHT WITH LOW
TEMPS FALLING INTO THE UPPER 50S. CLOUD COVER SHOULD REMAIN THICK
ENOUGH TO KEEP TEMPS UP A BIT.
ON SUNDAY THE UPPER LEVEL TROUGH RETROGRADES A BIT ACROSS THE OHIO
RIVER VALLEY AND INSTABILITY ASSOCIATED WITH THE LOW MAY HELP A FEW
SHOWERS AND THUNDERSTORMS FORM ON SUNDAY. AREAS ALONG AND SOUTH OF
I-80 HAVE THE BEST CHANCE FOR A PASSING SHOWER OR THUNDERSTORM.
COVERAGE SHOULD REMAIN SPARSE AND A RAIN OUT IS NOT EXPECTED.
ANOTHER DRY NIGHT IS EXPECTED SUNDAY NIGHT. SUNDAY LOOKS A BIT
WARMER WITH HIGHS IN THE MID 70S BUT CLOUDS SHOULD THIN SUNDAY NIGHT
SO WENT A FEW DEGREES COOLER SUNDAY NIGHT.
EXTENDED...MONDAY THROUGH THURSDAY...
THE LARGE LOW PRESSURE REMAINS OVER THE EAST COAST WHILE HIGH
PRESSURE SINKS SOUTH OUT OF CANADA REACHING THE CWA ON MONDAY. THE
UPPER LEVEL TROUGH WILL REMAIN OVERHEAD THROUGHOUT THE EXTENDED WITH
DISTURBANCES ROTATING AROUND IT. AS SUCH LEFT PERIODIC CHANCES OF
SHOWERS AND THUNDERSTORMS IN THE FORECAST. TEMPS REMAIN BELOW
NORMAL THANKS TO THE UPPER LEVEL LOW AND NORTHERLY SURFACE FLOW.
HOWEVER LOOKING LIKE WE MIGHT SEE HIGHS IN THE 80S BY LATE NEXT
WEEK.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* PERIODS OF SHRA WITH ISOLATED TSRA THROUGH 22Z. SOME STORMS MAY
HAVE GUSTS IN EXCESS OF 40 MPH.
* MVFR CIGS ARRIVING THIS EVENING WITH A GOOD CHANCE...ESPECIALLY
FOR LATE JUNE...FOR IFR LATER TONIGHT INTO SAT MORNING.
* NORTHWEST WINDS TURN NORTH LATE THIS EVENING/OVERNIGHT.
* CHANCE FOR SHRA ON SAT AFTERNOON.
//DISCUSSION...UPDATED 18Z...
BROAD LOW PRESSURE ACROSS THE EASTERN GREAT LAKES AND NEW ENGLAND
WILL CONTINUE TO PRESENT NORTHERLY FLOW OVER THE TAF SITES INTO
THIS WEEKEND. AN UPPER LEVEL DISTURBANCE MOVING OVERHEAD THIS
AFTERNOON INTO THE EARLY EVE WILL PRESENT THE GREATEST COVERAGE OF
SHOWERS THROUGH THE NEXT 24 HOURS...WITH ISOLATED TO SCATTERED
THUNDER LIKELY. SOME OF THESE INDIVIDUAL STORMS/SHOWERS COULD BE
GUSTY GIVEN THE ENVIRONMENT...PUTTING OUT GUST FRONTS THAT WILL
EXTEND A WAYS FROM THE ACTUAL RAIN. COVERAGE IS ANTICIPATED TO BE
AROUND 70 PERCENT ACROSS CHICAGOLAND FROM 20Z-23Z. COVERAGE WILL
BE SLOW TO WANE THROUGH 02Z-04Z THOUGH DIMINISHING INSTABILITY
SHOULD ALLOW THE THUNDER THREAT TO DROP QUICKLY THIS EVE. NW WINDS
WILL TURN NNE AT SOME POINT TONIGHT...THOUGH CONFIDENCE IN EXACT
TIMING REMAINS LOW. WINDS LOOK TO BE NNE TO NE ON SAT...AT LEAST
BY LATE MORNING INTO THE AFTERNOON WITH HIGHER CONFIDENCE.
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE IN SHRA WITH MEDIUM CONFIDENCE IN TSRA. HIGH
CONFIDENCE IN DURATION OF SHRA AND TSRA...ALTHOUGH TIMES OF
SHRA/TSRA AT THE AIRFIELD MAY BE BRIEF.
* HIGH CONFIDENCE IN MVFR ARRIVING AT SOME POINT THIS EVE AND
MEDIUM CONFIDENCE IN IFR. LOW CONFIDENCE IN IFR DURATION.
* MEDIUM CONFIDENCE IN WIND DIRECTION AND SPEED. WINDS MAY TURN
SHARPLY NEAR OUTFLOW BOUNDARIES FROM SHOWERS THIS AFTERNOON.
* LOW CONFIDENCE IN SCT SHRA SAT AFTERNOON.
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT THROUGH SUNDAY...VFR.
MONDAY...VFR. CHANCE FOR SHOWERS MONDAY EVENING.
TUESDAY THROUGH THURSDAY...DRY AND VFR.
MTF
&&
.MARINE...
251 AM CDT
LOW PRESSURE OVER SOUTHERN NEW YORK WILL LIFT NORTHWARD INTO
SOUTHERN QUEBEC TODAY AND TONIGHT BEFORE TURNING NORTHEASTWARD UP
THE ST. LAWRENCE VALLEY LATER SATURDAY. A TROUGH EXTENDS
NORTHWESTWARD ACROSS LAKE SUPERIOR WITH ANOTHER WEAKER LOW
CIRCULATION NEAR SOUTHERN LAKE HURON. AN UPPER LEVEL TROUGH WILL
MOVE ACROSS THE LAKE TODAY WHILE THE LOW NEAR LAKE HURON PIVOTS
EASTWARD DRAGGING A COLD FRONT SOUTHWARD DOWN THE LAKE. WESTERLY
WINDS WILL TURN NORTH AND NORTHEAST BEHIND THE FRONT BY EVENING AND
LIKELY CONTINUE THROUGH EARLY NEXT WEEK. THE PRESSURE GRADIENT WILL
TIGHTEN ACROSS THE LAKE SATURDAY ALLOWING FOR AN INCREASE IN WIND
SPEEDS TONIGHT AND SATURDAY BEFORE EASING LATER SUNDAY. WHILE MIXING
WILL LIKELY BE MUTED BY THE STRONG MARINE LAYER THE GRADIENT WILL BE
RATHER STRONG SO 20-25 KT SPEEDS ARE EXPECTED. THIS WILL SET UP A
LONG FETCH DOWN THE LAKE FOR ALLOWING WAVES TO BUILD...LIKELY TO
SMALL CRAFT ADVISORY LEVEL STARTING SATURDAY MORNING OR EARLY
SATURDAY AFTERNOON WITH SLIGHT IMPROVEMENT POSSIBLE SUNDAY. THE
NORTHERLY WINDS LOOK TO CONTINUE THROUGH TUESDAY WHEN WEAK HIGH
PRESSURE WILL BE ACROSS THE GREAT LAKES AND MISSISSIPPI VALLEY. THE
HIGH WILL THEN SHIFT OFF TO THE EAST ALLOWING SOUTHERLY WINDS TO
RETURN.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...BEACH HAZARDS STATEMENT...ILZ006-ILZ014...4 PM SATURDAY TO 3 AM
MONDAY.
IN...BEACH HAZARDS STATEMENT...INZ001-INZ002...9 AM SATURDAY TO 3 AM
MONDAY.
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...UPDATED
NWS CHICAGO/ROMEOVILLE IL
232 PM CDT FRI JUN 28 2013
.MESOSCALE DISCUSSION...
230 PM CDT
MONITORING GUSTY STORMS ACROSS NORTH CENTRAL TO NORTHEAST IL. A
COUPLE ARCS OF CONVECTION HAVE DEVELOPED ON THE LEADING EDGE OF
THE INCOMING SHORT WAVE. THIS LEADING EDGE HAS AN UNSTABLE
ATMOSPHERE TO WORK WITH GIVEN SURFACE TEMPERATURES SEVERAL
DEGREES ABOVE CONVECTIVE TEMPS PER MORNING SOUNDINGS AND AMDAR
DATA. NICE INVERTED-V SHAPE SOUNDINGS ARE PRESENT UP TO 5000-6000
FT WITH ASSOCIATED DOWNDRAFT CAPE ANALYZED BY THE RAP IN EXCESS OF
800 J/KG. THE STORM MOVING ACROSS SOUTHERN KANE NOW HAS PRODUCED A
46 MPH GUST AT DEKALB...AN ESTIMATED 50 MPH GUST AT HINKLEY...AND
A MEASURED 52 MPH GUST AT AURORA. THIS IS THE MOST ORGANIZED
STORM BUT ANY OF THESE WILL HAVE THE POTENTIAL TO PRODUCE
WINDS...AND POSSIBLY SOME SMALL HAIL. WILL CONTINUE WITH SPECIAL
WEATHER STATEMENTS ON THESE BUT WOULD NOT BE SURPRISED TO HAVE A
BRIEF SEVERE THUNDERSTORM WARNING OR TWO...ESPECIALLY ON THESE
LEADING TWO ARCS.
MTF
&&
.DISCUSSION...
1135 AM CDT
ONLY SOME MINOR TWEAKS TO SHORT TERM FORECAST GRIDS FOR THE REST
OF TODAY AND THIS EVENING TO ACCOUNT FOR RECENT AND CURRENT
TEMPERATURE...DEW POINT AND CLOUD TRENDS.
A SMALL VORT MAX IN THE NW UPPER FLOW DROPPED SE TO SE WI
OVERNIGHT PRODUCING SOME MINOR SHOWERS AND AN ISOLATED TS. BUT MID
MORNING IT HAD MOVES OUT OF SOUTHERN LAKE MI AND IS CURRENTLY
UPPER APPROACHING THE SW SHORE OF LOWER MI AND WILL NOT POSE ANY
THREAT OF SHRA OR TS TO THE LOCAL AREA.
UPSTREAM...WATER VAPOR SATELLITE LOOPS SHOW ANOTHER SHORT
WAVE/VORT MAX HAS BEEN QUICKLY DROPPING SSE FROM E CENTRAL MN TO
W CENTRAL WI THIS MORNING. NAM12 AND RUC13 SEEM TO HAVE A DECENT
HANDLE ON THIS FEATURE AND TURN IT MORE SE AS IT STARTS TO ENTER
THE BROAD UPPER TROUGH FROM THE UPPER MIDWEST E TO THE NEW
ENGLAND COAST AND S TO THE MID MS...OH...AND TN VALLEYS...AND THE
MID ATLANTIC COAST.
EXTRAPOLATION OF RECENT MOVEMENT OF THE WI SHORT WAVE IS IN DECENT
AGREEMENT WITH ABOVE MENTIONED MODELS BRINGING THE THE SHORT WAVE
TROUGH S OF THE WI BORDER BETWEEN 20 AND 21Z. SIGNIFICANT MID
LEVEL COOLING OCCUR ED SINCE YESTERDAY AND WHILE MODELS TEMPERATURE
PROFILES SHOW WARMING DURING THE DAY BY 29.00Z THERE IS STILL A
DEEP ALBEIT MUCH NARROW AREA OF CAPE OVER THE LOCAL AREA THAN THIS
MORNING. STILL...WITH CONVECTIVE TEMPERATURES TO BE REACHED BY
NOON EXPECT TO SEE QUICK CU DEVELOPMENT AHEAD OF LARGE AREA OF
CLOUDS ADVECTING ACROSS SOUTHERN WI TOWARD NORTHERN IL AND NW IN.
AS OF 1125 AM CDT RADAR COMPOSITE LOOP SHOWED ONLY SCATTERED SMALL
LIGHT SHOWERS UPSTREAM OF THE LOCAL FORECAST AREA BUT WITH SOME
ADDITIONAL HEATING AVAILABLE THROUGH DECREASING ML-CAPE OF 1200
TO 2000 J/KG DEPENDING ON WHICH MODEL OVER THE AREA AND DECENT UVV
IN THE LOWER AND MID LEVELS AHEAD OF THE APPROACHING SHORT WAVE
TROUGH FEEL THAT ALONG WITH INCREASING CLOUDY COVER TO BROKEN OR
NEAR OVERCAST PROBABILITY OF SHOWERS WILL BE INCREASING TO LIKELY
DURING THE AFTERNOON...WITH ALSO A SOME THUNDERSTORMS OCCURRING.
TRS
//PREV DISCUSSION...
339 AM CDT
SYNOPSIS...THE LARGE SCALE PATTERN WILL NOT CHANGE MUCH OVER THE
NEXT WEEK WITH A LARGE RIDGE OVER THE WESTERN U.S. AND A TROUGH OVER
THE EASTERN U.S. STORMS ARE EXPECTED TODAY AND TOMORROW WITH A BRIEF
DRY PERIOD EXPECTED EARLY NEXT WEEK. ALSO EXPECTED IS A COOL PERIOD
AS NORTH FLOW SETS UP SATURDAY.
TODAY AND TONIGHT...
THE SURFACE LOW THAT IS CENTERED OVER NEW ENGLAND AND STRETCHES BACK
TO LAKE SUPERIOR WILL SINK SOUTH TODAY. IN ADDITION THE UPPER LEVEL
JET EXIT WILL ALSO BE SINKING SOUTH THROUGH THE CWA WITH THE LEFT
JET EXIT REGION OVERHEAD DURING PRIME HEATING THIS AFTERNOON. LONG
SKINNY CAPE OF UP TO 1000 J/KG IS FORECAST AND SHEAR WILL BE MINIMAL
AT BEST...10 KT OR SO. THEREFORE EXPECTING SCATTERED STORMS TO
SPROUT FIRST ALONG THE IL/WI STATE LINE AROUND NOON AND SCATTERED
THUNDERSTORMS SHOULD SPREAD ACROSS THE CWA EARLY THIS AFTERNOON.
LATER IN THE AFTERNOON AS THE WAVE COMES THROUGH EXPECTING THE MAIN
THUNDERSTORM ACTIVITY TO BE EAST OF A NORTHWEST BOONE COUNTY TO
SOUTH CENTRAL IROQUOIS COUNTY LINE. SCATTERED THUNDERSTORMS ARE
CERTAINLY POSSIBLE WEST OF THAT LINE AS WELL...BUT THINKING THE
STRONGER STORMS AND BETTER COVERAGE WILL BE EAST OF THE LINE.
STORMS WILL LIKELY BE PULSEY AND UNORGANIZED AS THERE IS A DECENT
AMOUNT OF CAPE BUT NOT ENOUGH SHEAR FOR LONG LIVED ORGANIZED STORMS.
THE DIURNAL CONVECTION WILL WIND DOWN AFTER SUNSET WITH SCATTERED
SHOWERS OVERNIGHT. ENJOY THE TEMPS TODAY BECAUSE A COOL DOWN IS
EXPECTED TOMORROW. HIGHS WILL RANGE FROM AROUND 80 TO THE MID 80S.
SATURDAY AND SUNDAY...
WINDS TURN NORTH SATURDAY BEHIND THE UPPER LEVEL TROUGH AND MUCH
COOLER AIR MOVES INTO THE REGION. THE UPPER LEVEL TROUGH SPLITS
WITH THE SOUTHERN LOW BECOMING A CLOSED LOW OVER OHIO LATE SATURDAY
NIGHT. YET ANOTHER UPPER LEVEL DISTURBANCE PASSES OVER THE WESTERN
HALF OF THE CWA SPARKING ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS
PRIMARILY WEST OF THE CHICAGO METRO. CAPE WILL BE VERY LOW ON
SATURDAY WITH MAYBE A FEW HUNDRED J/KG AVAILABLE. SHEAR WILL BE A
BIT MORE FAVORABLE FOR ORGANIZED CONVECTION...BUT THINKING GENERAL
THUNDERSTORMS WILL BE THE MAIN SHOW.
THE DIURNAL SHOWERS AND THUNDERSTORMS DISSIPATE OVERNIGHT WITH LOW
TEMPS FALLING INTO THE UPPER 50S. CLOUD COVER SHOULD REMAIN THICK
ENOUGH TO KEEP TEMPS UP A BIT.
ON SUNDAY THE UPPER LEVEL TROUGH RETROGRADES A BIT ACROSS THE OHIO
RIVER VALLEY AND INSTABILITY ASSOCIATED WITH THE LOW MAY HELP A FEW
SHOWERS AND THUNDERSTORMS FORM ON SUNDAY. AREAS ALONG AND SOUTH OF
I-80 HAVE THE BEST CHANCE FOR A PASSING SHOWER OR THUNDERSTORM.
COVERAGE SHOULD REMAIN SPARSE AND A RAIN OUT IS NOT EXPECTED.
ANOTHER DRY NIGHT IS EXPECTED SUNDAY NIGHT. SUNDAY LOOKS A BIT
WARMER WITH HIGHS IN THE MID 70S BUT CLOUDS SHOULD THIN SUNDAY NIGHT
SO WENT A FEW DEGREES COOLER SUNDAY NIGHT.
EXTENDED...MONDAY THROUGH THURSDAY...
THE LARGE LOW PRESSURE REMAINS OVER THE EAST COAST WHILE HIGH
PRESSURE SINKS SOUTH OUT OF CANADA REACHING THE CWA ON MONDAY. THE
UPPER LEVEL TROUGH WILL REMAIN OVERHEAD THROUGHOUT THE EXTENDED WITH
DISTURBANCES ROTATING AROUND IT. AS SUCH LEFT PERIODIC CHANCES OF
SHOWERS AND THUNDERSTORMS IN THE FORECAST. TEMPS REMAIN BELOW
NORMAL THANKS TO THE UPPER LEVEL LOW AND NORTHERLY SURFACE FLOW.
HOWEVER LOOKING LIKE WE MIGHT SEE HIGHS IN THE 80S BY LATE NEXT
WEEK.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* PERIODS OF SHRA WITH ISOLATED TSRA AFTER 1930Z. SOME STORMS MAY
HAVE GUSTS IN EXCESS OF 40 MPH.
* MVFR CIGS ARRIVING THIS EVENING WITH A GOOD CHANCE...ESPECIALLY
FOR LATE JUNE...FOR IFR LATER TONIGHT INTO SAT MORNING.
* NORTHWEST WINDS TURN NORTH LATE THIS EVENING/OVERNIGHT.
* CHANCE FOR SHRA ON SAT AFTERNOON.
//DISCUSSION...UPDATED 18Z...
BROAD LOW PRESSURE ACROSS THE EASTERN GREAT LAKES AND NEW ENGLAND
WILL CONTINUE TO PRESENT NORTHERLY FLOW OVER THE TAF SITES INTO
THIS WEEKEND. AN UPPER LEVEL DISTURBANCE MOVING OVERHEAD THIS
AFTERNOON INTO THE EARLY EVE WILL PRESENT THE GREATEST COVERAGE OF
SHOWERS THROUGH THE NEXT 24 HOURS...WITH ISOLATED TO SCATTERED
THUNDER LIKELY. SOME OF THESE INDIVIDUAL STORMS/SHOWERS COULD BE
GUSTY GIVEN THE ENVIRONMENT...PUTTING OUT GUST FRONTS THAT WILL
EXTEND A WAYS FROM THE ACTUAL RAIN. COVERAGE IS ANTICIPATED TO BE
AROUND 70 PERCENT ACROSS CHICAGOLAND FROM 20Z-23Z. COVERAGE WILL
BE SLOW TO WANE THROUGH 02Z-04Z THOUGH DIMINISHING INSTABILITY
SHOULD ALLOW THE THUNDER THREAT TO DROP QUICKLY THIS EVE. NW WINDS
WILL TURN NNE AT SOME POINT TONIGHT...THOUGH CONFIDENCE IN EXACT
TIMING REMAINS LOW. WINDS LOOK TO BE NNE TO NE ON SAT...AT LEAST
BY LATE MORNING INTO THE AFTERNOON WITH HIGHER CONFIDENCE.
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE IN SHRA WITH MEDIUM CONFIDENCE IN TSRA. HIGH
CONFIDENCE IN TIMING WINDOW OF SHRA AND TSRA...ALTHOUGH TIMES OF
SHRA/TSRA AT THE AIRFIELD MAY BE BRIEF.
* HIGH CONFIDENCE IN MVFR ARRIVING AT SOME POINT THIS EVE AND
MEDIUM CONFIDENCE IN IFR. LOW CONFIDENCE IN IFR DURATION.
* MEDIUM CONFIDENCE IN WIND DIRECTION AND SPEED. WINDS MAY TURN
SHARPLY NEAR OUTFLOW BOUNDARIES FROM SHOWERS THIS AFTERNOON.
* LOW CONFIDENCE IN SCT SHRA SAT AFTERNOON.
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT THROUGH SUNDAY...VFR.
MONDAY...VFR. CHANCE FOR SHOWERS MONDAY EVENING.
TUESDAY THROUGH THURSDAY...DRY AND VFR.
MTF
&&
.MARINE...
251 AM CDT
LOW PRESSURE OVER SOUTHERN NEW YORK WILL LIFT NORTHWARD INTO
SOUTHERN QUEBEC TODAY AND TONIGHT BEFORE TURNING NORTHEASTWARD UP
THE ST. LAWRENCE VALLEY LATER SATURDAY. A TROUGH EXTENDS
NORTHWESTWARD ACROSS LAKE SUPERIOR WITH ANOTHER WEAKER LOW
CIRCULATION NEAR SOUTHERN LAKE HURON. AN UPPER LEVEL TROUGH WILL
MOVE ACROSS THE LAKE TODAY WHILE THE LOW NEAR LAKE HURON PIVOTS
EASTWARD DRAGGING A COLD FRONT SOUTHWARD DOWN THE LAKE. WESTERLY
WINDS WILL TURN NORTH AND NORTHEAST BEHIND THE FRONT BY EVENING AND
LIKELY CONTINUE THROUGH EARLY NEXT WEEK. THE PRESSURE GRADIENT WILL
TIGHTEN ACROSS THE LAKE SATURDAY ALLOWING FOR AN INCREASE IN WIND
SPEEDS TONIGHT AND SATURDAY BEFORE EASING LATER SUNDAY. WHILE MIXING
WILL LIKELY BE MUTED BY THE STRONG MARINE LAYER THE GRADIENT WILL BE
RATHER STRONG SO 20-25 KT SPEEDS ARE EXPECTED. THIS WILL SET UP A
LONG FETCH DOWN THE LAKE FOR ALLOWING WAVES TO BUILD...LIKELY TO
SMALL CRAFT ADVISORY LEVEL STARTING SATURDAY MORNING OR EARLY
SATURDAY AFTERNOON WITH SLIGHT IMPROVEMENT POSSIBLE SUNDAY. THE
NORTHERLY WINDS LOOK TO CONTINUE THROUGH TUESDAY WHEN WEAK HIGH
PRESSURE WILL BE ACROSS THE GREAT LAKES AND MISSISSIPPI VALLEY. THE
HIGH WILL THEN SHIFT OFF TO THE EAST ALLOWING SOUTHERLY WINDS TO
RETURN.
MDB
&&
.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
107 PM CDT FRI JUN 28 2013
.DISCUSSION...
1135 AM CDT
ONLY SOME MINOR TWEAKS TO SHORT TERM FORECAST GRIDS FOR THE REST
OF TODAY AND THIS EVENING TO ACCOUNT FOR RECENT AND CURRENT
TEMPERATURE...DEW POINT AND CLOUD TRENDS.
A SMALL VORT MAX IN THE NW UPPER FLOW DROPPED SE TO SE WI
OVERNIGHT PRODUCING SOME MINOR SHOWERS AND AN ISOLATED TS. BUT MID
MORNING IT HAD MOVES OUT OF SOUTHERN LAKE MI AND IS CURRENTLY
UPPER APPROACHING THE SW SHORE OF LOWER MI AND WILL NOT POSE ANY
THREAT OF SHRA OR TS TO THE LOCAL AREA.
UPSTREAM...WATER VAPOR SATELLITE LOOPS SHOW ANOTHER SHORT
WAVE/VORT MAX HAS BEEN QUICKLY DROPPING SSE FROM E CENTRAL MN TO
W CENTRAL WI THIS MORNING. NAM12 AND RUC13 SEEM TO HAVE A DECENT
HANDLE ON THIS FEATURE AND TURN IT MORE SE AS IT STARTS TO ENTER
THE BROAD UPPER TROUGH FROM THE UPPER MIDWEST E TO THE NEW
ENGLAND COAST AND S TO THE MID MS...OH...AND TN VALLEYS...AND THE
MID ATLANTIC COAST.
EXTRAPOLATION OF RECENT MOVEMENT OF THE WI SHORT WAVE IS IN DECENT
AGREEMENT WITH ABOVE MENTIONED MODELS BRINGING THE THE SHORT WAVE
TROUGH S OF THE WI BORDER BETWEEN 20 AND 21Z. SIGNIFICANT MID
LEVEL COOLING OCCUR ED SINCE YESTERDAY AND WHILE MODELS TEMPERATURE
PROFILES SHOW WARMING DURING THE DAY BY 29.00Z THERE IS STILL A
DEEP ALBEIT MUCH NARROW AREA OF CAPE OVER THE LOCAL AREA THAN THIS
MORNING. STILL...WITH CONVECTIVE TEMPERATURES TO BE REACHED BY
NOON EXPECT TO SEE QUICK CU DEVELOPMENT AHEAD OF LARGE AREA OF
CLOUDS ADVECTING ACROSS SOUTHERN WI TOWARD NORTHERN IL AND NW IN.
AS OF 1125 AM CDT RADAR COMPOSITE LOOP SHOWED ONLY SCATTERED SMALL
LIGHT SHOWERS UPSTREAM OF THE LOCAL FORECAST AREA BUT WITH SOME
ADDITIONAL HEATING AVAILABLE THROUGH DECREASING ML-CAPE OF 1200
TO 2000 J/KG DEPENDING ON WHICH MODEL OVER THE AREA AND DECENT UVV
IN THE LOWER AND MID LEVELS AHEAD OF THE APPROACHING SHORT WAVE
TROUGH FEEL THAT ALONG WITH INCREASING CLOUDY COVER TO BROKEN OR
NEAR OVERCAST PROBABILITY OF SHOWERS WILL BE INCREASING TO LIKELY
DURING THE AFTERNOON...WITH ALSO A SOME THUNDERSTORMS OCCURRING.
TRS
//PREV DISCUSSION...
339 AM CDT
SYNOPSIS...THE LARGE SCALE PATTERN WILL NOT CHANGE MUCH OVER THE
NEXT WEEK WITH A LARGE RIDGE OVER THE WESTERN U.S. AND A TROUGH OVER
THE EASTERN U.S. STORMS ARE EXPECTED TODAY AND TOMORROW WITH A BRIEF
DRY PERIOD EXPECTED EARLY NEXT WEEK. ALSO EXPECTED IS A COOL PERIOD
AS NORTH FLOW SETS UP SATURDAY.
TODAY AND TONIGHT...
THE SURFACE LOW THAT IS CENTERED OVER NEW ENGLAND AND STRETCHES BACK
TO LAKE SUPERIOR WILL SINK SOUTH TODAY. IN ADDITION THE UPPER LEVEL
JET EXIT WILL ALSO BE SINKING SOUTH THROUGH THE CWA WITH THE LEFT
JET EXIT REGION OVERHEAD DURING PRIME HEATING THIS AFTERNOON. LONG
SKINNY CAPE OF UP TO 1000 J/KG IS FORECAST AND SHEAR WILL BE MINIMAL
AT BEST...10 KT OR SO. THEREFORE EXPECTING SCATTERED STORMS TO
SPROUT FIRST ALONG THE IL/WI STATE LINE AROUND NOON AND SCATTERED
THUNDERSTORMS SHOULD SPREAD ACROSS THE CWA EARLY THIS AFTERNOON.
LATER IN THE AFTERNOON AS THE WAVE COMES THROUGH EXPECTING THE MAIN
THUNDERSTORM ACTIVITY TO BE EAST OF A NORTHWEST BOONE COUNTY TO
SOUTH CENTRAL IROQUOIS COUNTY LINE. SCATTERED THUNDERSTORMS ARE
CERTAINLY POSSIBLE WEST OF THAT LINE AS WELL...BUT THINKING THE
STRONGER STORMS AND BETTER COVERAGE WILL BE EAST OF THE LINE.
STORMS WILL LIKELY BE PULSEY AND UNORGANIZED AS THERE IS A DECENT
AMOUNT OF CAPE BUT NOT ENOUGH SHEAR FOR LONG LIVED ORGANIZED STORMS.
THE DIURNAL CONVECTION WILL WIND DOWN AFTER SUNSET WITH SCATTERED
SHOWERS OVERNIGHT. ENJOY THE TEMPS TODAY BECAUSE A COOL DOWN IS
EXPECTED TOMORROW. HIGHS WILL RANGE FROM AROUND 80 TO THE MID 80S.
SATURDAY AND SUNDAY...
WINDS TURN NORTH SATURDAY BEHIND THE UPPER LEVEL TROUGH AND MUCH
COOLER AIR MOVES INTO THE REGION. THE UPPER LEVEL TROUGH SPLITS
WITH THE SOUTHERN LOW BECOMING A CLOSED LOW OVER OHIO LATE SATURDAY
NIGHT. YET ANOTHER UPPER LEVEL DISTURBANCE PASSES OVER THE WESTERN
HALF OF THE CWA SPARKING ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS
PRIMARILY WEST OF THE CHICAGO METRO. CAPE WILL BE VERY LOW ON
SATURDAY WITH MAYBE A FEW HUNDRED J/KG AVAILABLE. SHEAR WILL BE A
BIT MORE FAVORABLE FOR ORGANIZED CONVECTION...BUT THINKING GENERAL
THUNDERSTORMS WILL BE THE MAIN SHOW.
THE DIURNAL SHOWERS AND THUNDERSTORMS DISSIPATE OVERNIGHT WITH LOW
TEMPS FALLING INTO THE UPPER 50S. CLOUD COVER SHOULD REMAIN THICK
ENOUGH TO KEEP TEMPS UP A BIT.
ON SUNDAY THE UPPER LEVEL TROUGH RETROGRADES A BIT ACROSS THE OHIO
RIVER VALLEY AND INSTABILITY ASSOCIATED WITH THE LOW MAY HELP A FEW
SHOWERS AND THUNDERSTORMS FORM ON SUNDAY. AREAS ALONG AND SOUTH OF
I-80 HAVE THE BEST CHANCE FOR A PASSING SHOWER OR THUNDERSTORM.
COVERAGE SHOULD REMAIN SPARSE AND A RAIN OUT IS NOT EXPECTED.
ANOTHER DRY NIGHT IS EXPECTED SUNDAY NIGHT. SUNDAY LOOKS A BIT
WARMER WITH HIGHS IN THE MID 70S BUT CLOUDS SHOULD THIN SUNDAY NIGHT
SO WENT A FEW DEGREES COOLER SUNDAY NIGHT.
EXTENDED...MONDAY THROUGH THURSDAY...
THE LARGE LOW PRESSURE REMAINS OVER THE EAST COAST WHILE HIGH
PRESSURE SINKS SOUTH OUT OF CANADA REACHING THE CWA ON MONDAY. THE
UPPER LEVEL TROUGH WILL REMAIN OVERHEAD THROUGHOUT THE EXTENDED WITH
DISTURBANCES ROTATING AROUND IT. AS SUCH LEFT PERIODIC CHANCES OF
SHOWERS AND THUNDERSTORMS IN THE FORECAST. TEMPS REMAIN BELOW
NORMAL THANKS TO THE UPPER LEVEL LOW AND NORTHERLY SURFACE FLOW.
HOWEVER LOOKING LIKE WE MIGHT SEE HIGHS IN THE 80S BY LATE NEXT
WEEK.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* PERIODS OF SHRA WITH ISOLATED TSRA AFTER 1930Z. SOME STORMS MAY
HAVE GUSTS IN EXCESS OF 40 MPH.
* MVFR CIGS ARRIVING THIS EVENING WITH A GOOD CHANCE...ESPECIALLY
FOR LATE JUNE...FOR IFR LATER TONIGHT INTO SAT MORNING.
* NORTHWEST WINDS TURN NORTH LATE THIS EVENING/OVERNIGHT.
* CHANCE FOR SHRA ON SAT AFTERNOON.
//DISCUSSION...UPDATED 18Z...
BROAD LOW PRESSURE ACROSS THE EASTERN GREAT LAKES AND NEW ENGLAND
WILL CONTINUE TO PRESENT NORTHERLY FLOW OVER THE TAF SITES INTO
THIS WEEKEND. AN UPPER LEVEL DISTURBANCE MOVING OVERHEAD THIS
AFTERNOON INTO THE EARLY EVE WILL PRESENT THE GREATEST COVERAGE OF
SHOWERS THROUGH THE NEXT 24 HOURS...WITH ISOLATED TO SCATTERED
THUNDER LIKELY. SOME OF THESE INDIVIDUAL STORMS/SHOWERS COULD BE
GUSTY GIVEN THE ENVIRONMENT...PUTTING OUT GUST FRONTS THAT WILL
EXTEND A WAYS FROM THE ACTUAL RAIN. COVERAGE IS ANTICIPATED TO BE
AROUND 70 PERCENT ACROSS CHICAGOLAND FROM 20Z-23Z. COVERAGE WILL
BE SLOW TO WANE THROUGH 02Z-04Z THOUGH DIMINISHING INSTABILITY
SHOULD ALLOW THE THUNDER THREAT TO DROP QUICKLY THIS EVE. NW WINDS
WILL TURN NNE AT SOME POINT TONIGHT...THOUGH CONFIDENCE IN EXACT
TIMING REMAINS LOW. WINDS LOOK TO BE NNE TO NE ON SAT...AT LEAST
BY LATE MORNING INTO THE AFTERNOON WITH HIGHER CONFIDENCE.
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE IN SHRA WITH MEDIUM CONFIDENCE IN TSRA. HIGH
CONFIDENCE IN TIMING WINDOW OF SHRA AND TSRA...ALTHOUGH TIMES OF
SHRA/TSRA AT THE AIRFIELD MAY BE BRIEF.
* HIGH CONFIDENCE IN MVFR ARRIVING AT SOME POINT THIS EVE AND
MEDIUM CONFIDENCE IN IFR. LOW CONFIDENCE IN IFR DURATION.
* MEDIUM CONFIDENCE IN WIND DIRECTION AND SPEED. WINDS MAY TURN
SHARPLY NEAR OUTFLOW BOUNDARIES FROM SHOWERS THIS AFTERNOON.
* LOW CONFIDENCE IN SCT SHRA SAT AFTERNOON.
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT THROUGH SUNDAY...VFR.
MONDAY...VFR. CHANCE FOR SHOWERS MONDAY EVENING.
TUESDAY THROUGH THURSDAY...DRY AND VFR.
MTF
&&
.MARINE...
251 AM CDT
LOW PRESSURE OVER SOUTHERN NEW YORK WILL LIFT NORTHWARD INTO
SOUTHERN QUEBEC TODAY AND TONIGHT BEFORE TURNING NORTHEASTWARD UP
THE ST. LAWRENCE VALLEY LATER SATURDAY. A TROUGH EXTENDS
NORTHWESTWARD ACROSS LAKE SUPERIOR WITH ANOTHER WEAKER LOW
CIRCULATION NEAR SOUTHERN LAKE HURON. AN UPPER LEVEL TROUGH WILL
MOVE ACROSS THE LAKE TODAY WHILE THE LOW NEAR LAKE HURON PIVOTS
EASTWARD DRAGGING A COLD FRONT SOUTHWARD DOWN THE LAKE. WESTERLY
WINDS WILL TURN NORTH AND NORTHEAST BEHIND THE FRONT BY EVENING AND
LIKELY CONTINUE THROUGH EARLY NEXT WEEK. THE PRESSURE GRADIENT WILL
TIGHTEN ACROSS THE LAKE SATURDAY ALLOWING FOR AN INCREASE IN WIND
SPEEDS TONIGHT AND SATURDAY BEFORE EASING LATER SUNDAY. WHILE MIXING
WILL LIKELY BE MUTED BY THE STRONG MARINE LAYER THE GRADIENT WILL BE
RATHER STRONG SO 20-25 KT SPEEDS ARE EXPECTED. THIS WILL SET UP A
LONG FETCH DOWN THE LAKE FOR ALLOWING WAVES TO BUILD...LIKELY TO
SMALL CRAFT ADVISORY LEVEL STARTING SATURDAY MORNING OR EARLY
SATURDAY AFTERNOON WITH SLIGHT IMPROVEMENT POSSIBLE SUNDAY. THE
NORTHERLY WINDS LOOK TO CONTINUE THROUGH TUESDAY WHEN WEAK HIGH
PRESSURE WILL BE ACROSS THE GREAT LAKES AND MISSISSIPPI VALLEY. THE
HIGH WILL THEN SHIFT OFF TO THE EAST ALLOWING SOUTHERLY WINDS TO
RETURN.
MDB
&&
.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
1135 AM CDT FRI JUN 28 2013
.DISCUSSION...
1135 AM CDT
ONLY SOME MINOR TWEAKS TO SHORT TERM FORECAST GRIDS FOR THE REST
OF TODAY AND THIS EVENING TO ACCOUNT FOR RECENT AND CURRENT
TEMPERATURE...DEW POINT AND CLOUD TRENDS.
A SMALL VORT MAX IN THE NW UPPER FLOW DROPPED SE TO SE WI
OVERNIGHT PRODUCING SOME MINOR SHOWERS AND AN ISOLATED TS. BUT MID
MORNING IT HAD MOVES OUT OF SOUTHERN LAKE MI AND IS CURRENTLY
UPPER APPROACHING THE SW SHORE OF LOWER MI AND WILL NOT POSE ANY
THREAT OF SHRA OR TS TO THE LOCAL AREA.
UPSTREAM...WATER VAPOR SATELLITE LOOPS SHOW ANOTHER SHORT
WAVE/VORT MAX HAS BEEN QUICKLY DROPPING SSE FROM E CENTRAL MN TO
W CENTRAL WI THIS MORNING. NAM12 AND RUC13 SEEM TO HAVE A DECENT
HANDLE ON THIS FEATURE AND TURN IT MORE SE AS IT STARTS TO ENTER
THE BROAD UPPER TROUGH FROM THE UPPER MIDWEST E TO THE NEW
ENGLAND COAST AND S TO THE MID MS...OH...AND TN VALLEYS...AND THE
MID ATLANTIC COAST.
EXTRAPOLATION OF RECENT MOVEMENT OF THE WI SHORT WAVE IS IN DECENT
AGREEMENT WITH ABOVE MENTIONED MODELS BRINGING THE THE SHORT WAVE
TROUGH S OF THE WI BORDER BETWEEN 20 AND 21Z. SIGNIFICANT MID
LEVEL COOLING OCCUR ED SINCE YESTERDAY AND WHILE MODELS TEMPERATURE
PROFILES SHOW WARMING DURING THE DAY BY 29.00Z THERE IS STILL A
DEEP ALBEIT MUCH NARROW AREA OF CAPE OVER THE LOCAL AREA THAN THIS
MORNING. STILL...WITH CONVECTIVE TEMPERATURES TO BE REACHED BY
NOON EXPECT TO SEE QUICK CU DEVELOPMENT AHEAD OF LARGE AREA OF
CLOUDS ADVECTING ACROSS SOUTHERN WI TOWARD NORTHERN IL AND NW IN.
AS OF 1125 AM CDT RADAR COMPOSITE LOOP SHOWED ONLY SCATTERED SMALL
LIGHT SHOWERS UPSTREAM OF THE LOCAL FORECAST AREA BUT WITH SOME
ADDITIONAL HEATING AVAILABLE THROUGH DECREASING ML-CAPE OF 1200
TO 2000 J/KG DEPENDING ON WHICH MODEL OVER THE AREA AND DECENT UVV
IN THE LOWER AND MID LEVELS AHEAD OF THE APPROACHING SHORT WAVE
TROUGH FEEL THAT ALONG WITH INCREASING CLOUDY COVER TO BROKEN OR
NEAR OVERCAST PROBABILITY OF SHOWERS WILL BE INCREASING TO LIKELY
DURING THE AFTERNOON...WITH ALSO A SOME THUNDERSTORMS OCCURRING.
TRS
&&
.PREV DISCUSSION...
339 AM CDT
SYNOPSIS...THE LARGE SCALE PATTERN WILL NOT CHANGE MUCH OVER THE
NEXT WEEK WITH A LARGE RIDGE OVER THE WESTERN U.S. AND A TROUGH OVER
THE EASTERN U.S. STORMS ARE EXPECTED TODAY AND TOMORROW WITH A BRIEF
DRY PERIOD EXPECTED EARLY NEXT WEEK. ALSO EXPECTED IS A COOL PERIOD
AS NORTH FLOW SETS UP SATURDAY.
TODAY AND TONIGHT...
THE SURFACE LOW THAT IS CENTERED OVER NEW ENGLAND AND STRETCHES BACK
TO LAKE SUPERIOR WILL SINK SOUTH TODAY. IN ADDITION THE UPPER LEVEL
JET EXIT WILL ALSO BE SINKING SOUTH THROUGH THE CWA WITH THE LEFT
JET EXIT REGION OVERHEAD DURING PRIME HEATING THIS AFTERNOON. LONG
SKINNY CAPE OF UP TO 1000 J/KG IS FORECAST AND SHEAR WILL BE MINIMAL
AT BEST...10 KT OR SO. THEREFORE EXPECTING SCATTERED STORMS TO
SPROUT FIRST ALONG THE IL/WI STATE LINE AROUND NOON AND SCATTERED
THUNDERSTORMS SHOULD SPREAD ACROSS THE CWA EARLY THIS AFTERNOON.
LATER IN THE AFTERNOON AS THE WAVE COMES THROUGH EXPECTING THE MAIN
THUNDERSTORM ACTIVITY TO BE EAST OF A NORTHWEST BOONE COUNTY TO
SOUTH CENTRAL IROQUOIS COUNTY LINE. SCATTERED THUNDERSTORMS ARE
CERTAINLY POSSIBLE WEST OF THAT LINE AS WELL...BUT THINKING THE
STRONGER STORMS AND BETTER COVERAGE WILL BE EAST OF THE LINE.
STORMS WILL LIKELY BE PULSEY AND UNORGANIZED AS THERE IS A DECENT
AMOUNT OF CAPE BUT NOT ENOUGH SHEAR FOR LONG LIVED ORGANIZED STORMS.
THE DIURNAL CONVECTION WILL WIND DOWN AFTER SUNSET WITH SCATTERED
SHOWERS OVERNIGHT. ENJOY THE TEMPS TODAY BECAUSE A COOL DOWN IS
EXPECTED TOMORROW. HIGHS WILL RANGE FROM AROUND 80 TO THE MID 80S.
SATURDAY AND SUNDAY...
WINDS TURN NORTH SATURDAY BEHIND THE UPPER LEVEL TROUGH AND MUCH
COOLER AIR MOVES INTO THE REGION. THE UPPER LEVEL TROUGH SPLITS
WITH THE SOUTHERN LOW BECOMING A CLOSED LOW OVER OHIO LATE SATURDAY
NIGHT. YET ANOTHER UPPER LEVEL DISTURBANCE PASSES OVER THE WESTERN
HALF OF THE CWA SPARKING ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS
PRIMARILY WEST OF THE CHICAGO METRO. CAPE WILL BE VERY LOW ON
SATURDAY WITH MAYBE A FEW HUNDRED J/KG AVAILABLE. SHEAR WILL BE A
BIT MORE FAVORABLE FOR ORGANIZED CONVECTION...BUT THINKING GENERAL
THUNDERSTORMS WILL BE THE MAIN SHOW.
THE DIURNAL SHOWERS AND THUNDERSTORMS DISSIPATE OVERNIGHT WITH LOW
TEMPS FALLING INTO THE UPPER 50S. CLOUD COVER SHOULD REMAIN THICK
ENOUGH TO KEEP TEMPS UP A BIT.
ON SUNDAY THE UPPER LEVEL TROUGH RETROGRADES A BIT ACROSS THE OHIO
RIVER VALLEY AND INSTABILITY ASSOCIATED WITH THE LOW MAY HELP A FEW
SHOWERS AND THUNDERSTORMS FORM ON SUNDAY. AREAS ALONG AND SOUTH OF
I-80 HAVE THE BEST CHANCE FOR A PASSING SHOWER OR THUNDERSTORM.
COVERAGE SHOULD REMAIN SPARSE AND A RAIN OUT IS NOT EXPECTED.
ANOTHER DRY NIGHT IS EXPECTED SUNDAY NIGHT. SUNDAY LOOKS A BIT
WARMER WITH HIGHS IN THE MID 70S BUT CLOUDS SHOULD THIN SUNDAY NIGHT
SO WENT A FEW DEGREES COOLER SUNDAY NIGHT.
EXTENDED...MONDAY THROUGH THURSDAY...
THE LARGE LOW PRESSURE REMAINS OVER THE EAST COAST WHILE HIGH
PRESSURE SINKS SOUTH OUT OF CANADA REACHING THE CWA ON MONDAY. THE
UPPER LEVEL TROUGH WILL REMAIN OVERHEAD THROUGHOUT THE EXTENDED WITH
DISTURBANCES ROTATING AROUND IT. AS SUCH LEFT PERIODIC CHANCES OF
SHOWERS AND THUNDERSTORMS IN THE FORECAST. TEMPS REMAIN BELOW
NORMAL THANKS TO THE UPPER LEVEL LOW AND NORTHERLY SURFACE FLOW.
HOWEVER LOOKING LIKE WE MIGHT SEE HIGHS IN THE 80S BY LATE NEXT
WEEK.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* SCATTERED TO NUMEROUS SHRA/TSRA THIS AFTERNOON. SOME MAY HAVE
GUSTS IN EXCESS OF 40 MPH.
* MVFR CIGS ARRIVING THIS EVENING WITH A GOOD CHANCE FOR IFR
TONIGHT.
* NORTHWEST WINDS TURN NORTH LATE THIS EVENING/OVERNIGHT.
//DISCUSSION...UPDATED 12Z...
MAIN CONCERN TODAY IS SCATTERED SHRA/TSRA EXPECTED TO ARRIVE WITH
THE PASSAGE OF AN UPPER LEVEL WAVE. RADAR/SATELLITE DEPICT A WEAK
WAVE JUST REACHING SOUTHERN LAKE MICHIGAN FROM THE NORTHWEST AND
BRINGING A BATCH OF MID CLOUD COVER AND A FEW LIGHT RAIN SHOWERS.
THIS WAVE WILL PASS TO THE EAST OF THE TERMINALS IN THE NEXT FEW
HOURS AND SHOULD MAINLY RESULT IN AN INCREASE IN CLOUDS. ATTENTION
TURNS TO THE UPPER LOW SPINNING OVER EASTERN LAKE SUPERIOR WITH A
TROUGH AXIS ORIENTED TO ITS NORTHWEST WHICH HAS MERGED WITH A WAVE
THAT WAS MOVING SOUTHEAST FROM THE CANADIAN PRAIRIES. THIS WAVE
WILL REACH THE AREA THIS AFTERNOON AND IS EXPECTED TO PRODUCE
SHRA/TSRA ACROSS THE AREA. WILL GO AHEAD AND INCREASE TO TEMPO
TSRA FOR A FEW HOURS THIS AFTERNOON BUT THERE COULD BE ACTIVITY
NEAR THE TERMINALS FOR MUCH OF THE AFTERNOON SO WILL CARRY A
LONGER PERIOD OF VCTS. ACTIVITY WILL WANE WITH SUNSET IF IT IS NOT
ALREADY SOUTHEAST OF THE AREA. A COOL FRONTAL BOUNDARY WILL ALSO
CROSS THE AREA LATER TODAY WHICH WILL TURN THE GUSTY WEST-
NORTHWEST WINDS TO NORTH OR EVEN NORTH-NORTHEAST OVERNIGHT. A MUCH
COOLER AIRMASS WILL SPREAD IN WITH MVFR CIGS LIKELY TO ACCOMPANY
IT WITH A DECENT CHANCE FOR IFR. SATELLITE DOES SHOW AN EXTENSIVE
AREA OF STRATUS ACROSS THE ARROWHEAD OF MINNESOTA AND MUCH OF
WESTERN ONTARIO WITH SURFACE OBS SHOWING EXTENSIVE IFR. HAVE
LOWERED CIGS TO IFR FOR A PERIOD TONIGHT AND AM THINKING CIGS WILL
IMPROVE TO MVFR SATURDAY MORNING.
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH CONFIDENCE IN SCATTERED SHRA/TSRA DEVELOPMENT AND MEDIUM
CONFIDENCE IN TIMING. LOW CONFIDENCE ON GUSTY STORMS OCCURRING
RIGHT OVER THE AIRFIELD.
* MEDIUM-HIGH CONFIDENCE IN MVFR CIGS ARRIVING SOME TIME THIS
EVENING AND CONTINUING INTO SATURDAY MORNING. MEDIUM CONFIDENCE
IN IFR DEVELOPING...LOW-MEDIUM CONFIDENCE IN TIMING.
* HIGH CONFIDENCE IN WIND TRENDS THROUGH THE AFTERNOON...MEDIUM
CONFIDENCE FROM THIS EVENING ON...MEDIUM CONFIDENCE IN
SPEEDS/GUSTS.
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT THROUGH SUNDAY...VFR.
MONDAY...VFR. CHANCE FOR SHOWERS MONDAY EVENING.
TUESDAY THROUGH THURSDAY...DRY AND VFR.
MDB/MTF
&&
.MARINE...
251 AM CDT
LOW PRESSURE OVER SOUTHERN NEW YORK WILL LIFT NORTHWARD INTO
SOUTHERN QUEBEC TODAY AND TONIGHT BEFORE TURNING NORTHEASTWARD UP
THE ST. LAWRENCE VALLEY LATER SATURDAY. A TROUGH EXTENDS
NORTHWESTWARD ACROSS LAKE SUPERIOR WITH ANOTHER WEAKER LOW
CIRCULATION NEAR SOUTHERN LAKE HURON. AN UPPER LEVEL TROUGH WILL
MOVE ACROSS THE LAKE TODAY WHILE THE LOW NEAR LAKE HURON PIVOTS
EASTWARD DRAGGING A COLD FRONT SOUTHWARD DOWN THE LAKE. WESTERLY
WINDS WILL TURN NORTH AND NORTHEAST BEHIND THE FRONT BY EVENING AND
LIKELY CONTINUE THROUGH EARLY NEXT WEEK. THE PRESSURE GRADIENT WILL
TIGHTEN ACROSS THE LAKE SATURDAY ALLOWING FOR AN INCREASE IN WIND
SPEEDS TONIGHT AND SATURDAY BEFORE EASING LATER SUNDAY. WHILE MIXING
WILL LIKELY BE MUTED BY THE STRONG MARINE LAYER THE GRADIENT WILL BE
RATHER STRONG SO 20-25 KT SPEEDS ARE EXPECTED. THIS WILL SET UP A
LONG FETCH DOWN THE LAKE FOR ALLOWING WAVES TO BUILD...LIKELY TO
SMALL CRAFT ADVISORY LEVEL STARTING SATURDAY MORNING OR EARLY
SATURDAY AFTERNOON WITH SLIGHT IMPROVEMENT POSSIBLE SUNDAY. THE
NORTHERLY WINDS LOOK TO CONTINUE THROUGH TUESDAY WHEN WEAK HIGH
PRESSURE WILL BE ACROSS THE GREAT LAKES AND MISSISSIPPI VALLEY. THE
HIGH WILL THEN SHIFT OFF TO THE EAST ALLOWING SOUTHERLY WINDS TO
RETURN.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
101 PM CDT FRI JUN 28 2013
.UPDATE...
ISSUED AT 1249 PM CDT FRI JUN 28 2013
CONVECTIVE CLOUDS HAVE DEVELOPED IN THE PAST 2 HRS AND CONVECTIVE
CELLS HAVE DEVELOPED IN THE PAST 45 MINUTES. CONVECTIVE TRENDS
WILL BE ON THE INCREASE THROUGH THE AFTERNOON WITH ISOLATED TO
SCATTERED SHOWERS AND A FEW THUNDERSTORMS.
CONVECTION DEVELOPING SOUTH OF I-80 IS MORE QUESTIONABLE.
HOWEVER...IF A REASONABLY STRONG CONVECTIVE CELL CAN DEVELOP THE
POTENTIAL IS THERE FOR WINDS GUSTING TO 40 MPH IN THE DOWNDRAFTS.
BASED ON CURRENT TEMPERATURES...HAVE RAISED MAX TEMPERATURES
SLIGHTLY. ..08..
UPDATE ISSUED AT 1006 AM CDT FRI JUN 28 2013
BASED ON DATA THROUGH 15Z...THERMALS SHOULD BEGIN DEVELOPING WITHIN
THE HOUR WITH DIURNAL CU BY MID DAY. AS SUCH THE REMAINDER OF THE
MORNING WILL REMAIN DRY ACROSS THE AREA.
RAP TRENDS INDICATE THE CONVECTIVE TEMPERATURE WILL SLOWLY DROP
DURING THE DAY WHICH WHEN COMBINED WITH THE APPROACHING VORT MAX
SHOULD INITIATE CONVECTION DURING THE AFTERNOON. CONVECTION IS
EXPECTED TO BE IN THE FORM OF SHOWERS WITH SOME THUNDERSTORMS.
CONVECTION WILL CONTINUE INTO THE EVENING WITH THE THUNDERSTORMS
DISSIPATING WITH SUNSET. HOWEVER...THE PROXIMITY OF THE COOL POOL
ALOFT AND UPPER LOW SHOULD KEEP SHOWERS GOING WELL INTO THE
EVENING AND OVERNIGHT HOURS WITH DECREASING COVERAGE. ..08..
&&
.SYNOPSIS...
ISSUED AT 300 AM CDT FRI JUN 28 2013
WATER VAPOR LOOPS SHOWED A BROAD UPPER TROUGH ACROSS THE GREAT
LAKES WITH A CLOSED LOW ON THE NORTHERN TIP OF LAKE SUPERIOR. A
STRONG SHORT WAVE/VORT MAX WAS LOCATED IN NORTHEAST MN. A FEW
SHOWERS WERE NOTED IN CENTRAL WI. OTHERWISE CLEAR SKIES WERE
ACROSS THE DVN CWA WHILE A LARGE MCS WAS COVERING SOUTHERN MO
AHEAD OF A COLD FRONT. CURRENT TEMPERATURES IN THE DVN CWA RANGED
FROM THE MID 60S TO LOWER 70S WITH DEWPOINTS IN THE UPPER 50S NW
TO UPPER 60S SE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 300 AM CDT FRI JUN 28 2013
FORECAST FOCUS ON SHOWER CHANCES...CLOUD TRENDS AND TEMPERATURES.
TODAY...OPERATIONAL MODELS SLIDE THE GREAT LAKES TROUGH SOUTHWARD
INTO OUR REGION WITH THE RAP DEPICTING A STRONG VORT MAX MOVING
FROM NORTHEAST MN INTO NORTHERN IL THIS AFTERNOON. WITH COOLING
TEMPERATURES ALOFT COMBINED WITH DAYTIME HEATING INSTABILITY WILL
INCREASE. HAVE CONFINED POPS TO THIS AFTERNOON AND ALSO ACROSS OUR
NORTHEAST HALF CWA CLOSER TO THE TRACK OF THE VORT MAX. THE HRRR
MESO MODEL DEPICTS THE POPCORN DESCRIPTION OF THE SCATTERED INSTABILITY
SHOWERS (AND A FEW THUNDERSTORMS) QUITE WELL. THERE WILL BE PLENTY OF
SUNSHINE FOR MOST OF THIS MORNING BUT CLOUDS WILL DEVELOP/FILL AS
THE CONVECTIVE TEMPERATURE IS REACHED. MAXIMUM TEMPERATURES WILL
RANGE FROM THE UPPER 70S NORTH TO THE MID 80S SOUTH BUT HUMIDITY
LEVELS WILL BE THANKFULLY LOWER COMPARED TO THE LAST FEW DAYS.
TONIGHT...WITH THE UPPER TROUGH OVER THE AREA WILL CONTINUE WITH
CHANCE POPS AS SKIES WILL BE MOSTLY CLOUDY OR BECOME MOSTLY CLOUDY.
HOWEVER...WITH THE LOSS OF HEATING/BETTER INSTABILITY THE COVERAGE OF
SHOWERS WILL DECREASE OVERNIGHT. MINIMUM TEMPERATURES SHOULD BE IN
THE LOWER 60S AT MOST LOCATIONS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 300 AM CDT FRI JUN 28 2013
A DIGGING UPPER TROF OVER THE EASTERN U.S IS FORECAST TO CLOSE OFF
OVER THE OHIO VALLEY BY LATE IN THE WEEKEND. THEN...MODELS ARE IN
AGREEMENT THAT THE CLOSED LOW WILL RETROGRADE INTO THE MID
MISSISSIPPI VALLEY EARLY IN THE WEEK AND REMAIN THERE...THEN
GRADUALLY FILLING DURING THE LATTER HALF OF THE WEEK.
THIS PATTERN WILL SUPPORT BELOW NORMAL TEMPERATURES THROUGH THE
FORECAST PERIOD WITH HIGHS GENERALLY IN THE 70S TO AROUND 80 AND
LOWS...ESPECIALLY EARLY IN THE WEEK...IN THE 50S.
MOST DAYS WILL HAVE AT LEAST A LOW THREAT OF RAIN.
HOWEVER...AS STATED IN THE PREVIOUS DISCUSSION...THE RAIN THREAT
WILL BE LIMITED TO JUST A FEW HOURS EACH DAY.
THE BETTER CHANCE OF RAIN DURING THE PERIOD WILL BE SATURDAY AS A
SERIES OF S/WS DROP INTO THE DEVELOPING TROF TO OUR EAST. THE
BETTER UPPER FORCING APPEARS TO BE JUST EAST OF THE
FORECAST AREA...SO KEPT THE HIGHER CHANCE AND LIKELY POPS NEAR AND
EAST OF THE MISSISSIPPI RIVER. THE RAIN THREAT WILL DIMINISH
SATURDAY NIGHT AND SUNDAY AS DRIER LOW LEVEL AIR FILTERS IN FROM THE
NORTH. THE DRY WEATHER SHOULD LAST THROUGH MONDAY THEN A LOW RAIN
THREAT RETURNS MONDAY NIGHT THROUGH THE END OF THE WEEK AS THE UPPER
LOW BACKS INTO THE REGION FROM THE EAST. THIS WILL SUPPORT MAINLY
AFTERNOON ISOLATED TO SCATTERED SHOWERS OR THUNDERSTORMS. SINCE ANY
SHRA/TSRA ACTIVITY WILL PROBABLY BE TIED TO AFTERNOON HEATING...HAVE
LIMITED THE POPS TO THE DAYTIME HOURS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1249 PM CDT FRI JUN 28 2013
CONVECTION HAS DEVELOPED ABOUT AN HOUR AHEAD OF SCHEDULE WITH SOME
SHRA ALONG THE WISCONSIN/ILLINOIS BORDER. VFR WX IS EXPECTED
THROUGH 06Z/29 WITH VCSH OR VCTS POSSIBLE AT KCID/KMLI. KDBQ HAS
THE BETTER CHANCE AT SEEING A SHRA OR TSRA. OVERALL INSTABILITY IS
LIMITED SO THE CHANCES OF A TSRA HITTING A TAF SITE IS LOW. AFT
06Z/29 CIGS WILL SLOWLY LOWER WITH MVFR CONDITIONS DVLPG AT KDBQ
BY SUNRISE AND KCID/KMLI AFT 12Z/29. ..08..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...08
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...DLF
AVIATION...08
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
148 PM EDT FRI JUN 28 2013
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 328 AM EDT FRI JUN 28 2013
CONDITIONS TODAY WILL BE FAIRLY SIMILAR TO WHAT HAPPENED DURING THE
DAY ON THURSDAY. SCATTERED SHOWERS AND STORMS WILL BEGIN TO DEVELOP
LATE THIS MORNING AND CONTINUE INTO THE EARLY EVENING HOURS. THE
BEST CHANCE FOR RAINFALL WILL OCCUR AWAY FROM LAKE MICHIGAN. PERIODS
OF SUNSHINE CAN BE EXPECTED IN BETWEEN SHOWERS THAT OCCUR. LESS IN
THE WAY OF RAINFALL IS EXPECTED ON SATURDAY...ALTHOUGH THE CHANCE
WILL STILL EXIST SATURDAY AFTERNOON AND EVENING. MOST LOCATIONS
SHOULD STAY DRY ON SUNDAY WITH MILD TEMPERATURES WELL INTO THE 70S
EXPECTED FOR HIGHS.
&&
.UPDATE...
ISSUED AT 740 AM EDT FRI JUN 28 2013
I UPDATED THE ZONES TO REFLECT THE AREA OF SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS NOW MOVING TOWARD MOP. THIS AREA SHOULD BE
EAST OF THE CWA BY 10 AM. RAP SOUNDINGS SHOW A MOIST LAYER BETWEEN
800 AND 600 MB BEING THE KICK-0FF FOR THESE SHOWERS WITH IN
COMBINATION WITH THE EDGE OF THE UPPER COLD POOL MOVING IN.
THE NEXT UPSTREAM SHORTWAVE WILL MOVE INTO THE AREA BY EARLY
AFTERNOON AND THE COMBINATION OF THAT THE COMBINED LAKE BREEZES
FROM LAKE HURON AND LAKE MICHIGAN SHOULD KEEP THE SHOWERS AND
THUNDERSTORMS MOSTLY EAST OF GRAND RAPIDS.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 328 AM EDT FRI JUN 28 2013
THE MAIN FOCUS OF THE FORECAST THROUGH THE WEEKEND REMAINS
CONVECTIVE TRENDS WITH THE UPPER LOW PARKED OVER THE REGION. THE
GENERAL TREND OF THE FCST REMAINS MAINLY UNCHANGED.
IT APPEARS THAT WE WILL HAVE SIMILAR CONDITIONS DURING THE DAY TODAY
AS COMPARED TO YESTERDAY REGARDING CONVECTION POTENTIAL. CONVECTIVE
DEVELOPMENT LOOKS LIKE IT WILL ONCE AGAIN BEGIN TO FIRE LATE IN THE
MORNING HOURS ACROSS THE NE CORNER OF THE CWFA. THIS IS DUE TO SFC
CONVERGENCE MAXIMIZED IN THAT LOCATION RESULTING FROM A SFC TROUGH
THIS IS DROPPING SOUTH THROUGH THE AREA. THE SFC TROUGH IS SUPPORTED
BY A LOBE OF THE NEWLY FORMED UPPER LOW DROPPING SOUTH.
THE SFC CONVERGENCE/UPPER WAVE WILL BE ACTING ON ML CAPES OF 1000+
J/KG BY 18Z THIS AFTERNOON. IN ADDITION...A SOMEWHAT WRLY COMPONENT
TO THE WIND WILL CONVERGE WITH A DEVELOPING LAKE BREEZE FROM LAKE
HURON/SAGINAW BAY TO ONLY HELP THE CAUSE. SEVERE WEATHER IS NOT
EXPECTED AS THE DEEP LAYER SHEAR IS ABOUT NIL WITH THE UPPER LOW
ALMOST DIRECTLY OVER THE AREA. WE CAN EXPECT SOME PULSE TYPE STORMS
WITH SOME POSSIBLE HAIL AS THE FREEZING LEVELS COME DOWN TO AROUND
11K FT OR SO. WE CAN NOT RULE OUT A DRY MICROBURST OF SOME
SUB-SEVERE WINDS. LOCALLY HEAVY RAINFALL WILL ALSO BE POSSIBLE WITH
THE SLOW MOVEMENT OF ANY STORMS. THE LAKESHORE WILL HAVE THE LEAST
CHC OF STORMS DUE TO THE STABILIZING EFFECTS OF LAKE MICHIGAN. WE
CAN NOT RULE OUT SOMETHING SURVIVING THE TRIP FROM WISCONSIN...BUT
THIS IS NOT LIKELY.
THE LOBE OF THE UPPER LOW WILL ALMOST BE THROUGH THE CWFA FIRST
THING ON SAT MORNING AT 12Z. IT WILL DROP SOUTH BY AFTERNOON LEAVING
SOME SHORT WAVE RIDGING IN THE WAKE OVER THE CWFA. THIS COMBINED
WITH SOME DRIER AIR ADVECTING IN FROM THE NE WILL LIMIT ML CAPES
FROM GETTING MUCH HIGHER THAN 500 J/KG DURING THE DAY ON SAT. THE
FLOW WILL BECOME NE WHICH WILL TAKE OUT THE STABILIZING EFFECTS FROM
LAKE MICHIGAN. IN FACT...SOME OF THE BEST CHCS OF SHOWERS/STORMS ON
SAT MIGHT BE ALONG THE LAKE BREEZE WITH THE W AND NE WINDS
CONVERGING AT A GOOD ANGLE. COVERAGE AND INTENSITY SHOULD BE LOWER
THAN TODAY. SEVERE WEATHER IS ONCE AGAIN NOT EXPECTED WITH SHEAR
VALUES BELOW 20 KNOTS.
THE THREAT FOR SHOWERS AND STORMS GOES DOWN EVEN MORE ON SUN AS EVEN
DRIER AIR ADVECTS IN AT THE LOWER LEVELS. ML CAPES ARE FCST TO ONLY
MAKE IT TO AROUND 200 J/KG AT BEST. THIS WILL KEEP A LID ON MOST
CONVECTION THAT TRIES TO DEVELOP...EXCEPT MAYBE RIGHT ALONG THE SRN
BORDER CLOSER TO THE MID LEVEL COLD POOL.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 328 AM EDT FRI JUN 28 2013
IT WOULD SEEM COOLER THAN NORMAL TEMPERATURES AND AFTERNOON AND
EVENING CONVECTION WILL BE THE PRIMARY WEATHER FEATURE THROUGH THIS
MOST OF THE COMING WEEK.
OVERALL THERE IS GOOD MODEL AGREEMENT WITH BOTH RUN TO RUN AND MODEL
TO MODEL OVER CONUS THROUGH THIS COMING WEEK. HOWEVER BY WEDNESDAY
THERE IS A CURIOUS DIFFERENCE OVER EASTERN CANADA BY BETWEEN THE
ECMWF AND THE GFS IN THAT THE ECMWF IS MUCH STRONGER AND DEEPER WITH
SYSTEM THAT DIVES SOUTH SOUTHEAST INTO QUEBEC. THIS WOULD SUGGEST A
MUCH STRONGER COLD FRONT IS HEADING SOUTH TOWARD THE NORTHERN
BOARDER STATES LATE IN THE WEEK THAN SHOWN ON THE GFS. HOWEVER FOR
THIS FORECAST TIME PERIOD THIS IS MORE OF A CURIOSITY THAN SOMETHING
WE HAVE TO WATCH CLOSELY.
THE MORE SIGNIFICANT ISSUE IS WE HAVE SPLIT FLOW OVER NORTH AMERICA
WITH THE NORTHERN BRANCH NEAR 70N AND THE SOUTHERN BRANCH CLIMBING
OVER THE WESTERN RIDGE NEAR 115W INTO SOUTHERN BRITISH COLUMBIA AND
MANITOBA... THEN DIVING SOUTHEAST TO NEAR THE GULF COAST WEST OF
MISSOURI RIVER AND THEN HEADING BACK NORTH TO NEW ENGLAND ALONG THE
EAST COAST. THIS DIP IN THE JET STREAM IS ANOMALOUS FOR THIS TIME OF
YEAR IS THE RESULT OF AN UPPER LOW THAT SOUTHERN GREAT LAKES THAT
SLOWLY RETROGRADES WEST OF THE MISSISSIPPI RIVER BY WEDNESDAY AS
SHORTWAVE ENERGY FROM THE SOUTHERN BRANCH DIVES INTO THE WESTERN
SIDE OF THE LONG WAVE TROUGH.
WHAT THIS DOES IS TO KEEP SOUTHWEST MICHIGAN IN OR NEAR CLOSED UPPER
LOW THROUGH MOST OF THE COMING WEEK. IN SUNDAY NIGHT TO MONDAY
PERIOD THE UPPER LOW IS FAR ENOUGH SOUTH AND EAST OF OUR AREA SO AS
TO ALLOW FOR SOME SURFACE RIDGING AND NORTHEAST SURFACE WINDS
BRINGING IN DRY SURFACE AIR. SO THAT IS A TIME WHEN THE
PRECIPITATION THREAT WOULD BE LOWEST. BY TUESDAY AND WEDNESDAY AS
THE SYSTEM REGRADES... THE SOUTHERLY FLOW ALOFT ON THE EAST SIDE OF
THE SYSTEM BRINGS MOISTURE BACK INTO THE REGION WITH DEEP
INSTABILITY THAT WILL LEAD TO LARGELY AFTERNOON AND EVENING
THUNDERSTORMS. THE SHEAR REMAINS LOW SO THE SEVERE STORM THREAT IS
LOW. BY JULY 4TH THE ECMWF SUGGEST UPPER RIDGING TRYING TO BUILD IN
WHILE THE GFS KEEP UPPER TROUGH OVER THE AREA. BOTH MODELS BUILD
IN AN UPPER RIDGE BY FRIDAY SO BY THEN IT SHOULD DRY OUT AND WARM UP
SOME.
THE BOTTOM LINE IS THE BEST CHANCE OF SHOWERS AND THUNDERSTORMS IS
TUE AND WEDNESDAY... THE DRIEST WEATHER SHOULD BE MONDAY AND FRIDAY.
TEMPERATURES WILL RUN BELOW NORMAL THROUGH FRIDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 148 PM EDT FRI JUN 28 2013
CURRENTLY HAVE VFR CONDITIONS AT ALL TAF SITES WITH THUNDERSTORMS
NORTH OF LANSING AND EAST OF THE FORECAST AREA. EXPECTING SCATTERED
SHOWERS AND THUNDERSTORMS TO DEVELOP OR MOVE ACROSS MOST OF THE AREA
THIS AFTERNOON AND EVENING. THUNDER MAY BE LACKING IN THE STABLE AIR
IN THE SHADOW OF LAKE MICHIGAN... SO HAVE NO THUNDER IN THE WESTERN
TAFS. THE SCATTERED NATURE OF THE STORMS SHOULD LIMIT IMPACT AT
TERMINAL FORECAST LOCATIONS AND WILL KEEP VICINITY WORDING.
FOG AND LOW CLOUDS LOOKING POSSIBLE AGAIN TONIGHT WITH IFR
VISIBILITIES AND MVFR/IFR CEILINGS. THIS SHOULD BURN OFF BY MID
MORNING SATURDAY.
CONVECTION IS POSSIBLE AGAIN ON SATURDAY... BUT THE INTENSITY AND
COVERAGE SHOULD BE REDUCED.
&&
.MARINE...
ISSUED AT 328 AM EDT FRI JUN 28 2013
NO MARINE HEADLINES ARE EXPECTED THROUGH THE WEEKEND. WE WILL SEE
WINDS GENERALLY RUNNING AROUND 10 TO 15 KNOTS EACH DAY FROM TODAY
THROUGH SUNDAY. THIS WILL PRODUCE WAVES OF GENERALLY 1 TO LOCALLY 3
FEET WITH THE HIGHEST WAVES EXPECTED SOUTH DUE TO THE NRLY FETCH.
&&
.HYDROLOGY...
ISSUED AT 328 AM EDT FRI JUN 28 2013
NO WIDESPREAD HYDROLOGY HEADLINES EXPECTED THROUGH EARLY NEXT WEEK.
WE WILL HAVE TO WATCH FOR SOME LOCALLY HEAVY RAINS FOR TODAY...
ALTHOUGH THE THREAT IS A LITTLE LOWER COMPARED TO THU. WE WILL SEE
DIURNAL SHOWERS AND STORMS DEVELOP ONCE AGAIN WITH VERY SLOW
MOVEMENT EXPECTED DUE TO THE LACK OF WIND IN THE CLOUD LAYER.
PRECIPITABLE WATER HAS DROPPED A LITTLE AS THE BEST MOISTURE AXIS
HAS MOVED AWAY AND DRIER AIR IS SLOWLY FILTERING IN. SOME FLOOD
ADVISORIES WILL BE POSSIBLE WHERE CONVECTION SITS FOR LONGER PERIOD
OF TIMES. THE THREAT WILL BECOME MUCH LOWER FOR THE REMAINDER OF THE
WEEKEND.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...WDM
SYNOPSIS...NJJ
SHORT TERM...NJJ
LONG TERM...WDM
AVIATION...63
HYDROLOGY...NJJ
MARINE...NJJ
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
240 PM EDT FRI JUN 28 2013
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL REMAIN OVER THE REGION THROUGH
THE WEEKEND. THIS SYSTEM WILL PRODUCE SHOWERS AND THUNDERSTORMS
THROUGH THE PERIOD WITH THE MOST WIDESPREAD COVERAGE OCCURRING
DURING THE DAYLIGHT HOURS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATED AT 1145 AM... SURFACE LOW PRESSURE DOWN TO 996 MB OVER
NORTHEAST NY MOVING NORTHEAST. MAIN CONCERN OVER THE NEXT SEVERAL
HOURS WILL BE FOR POTENTIAL FOR SHOWERS AND THUNDERSTORMS
PRODUCING ISOLATED FLASH FLOODING THIS AFTERNOON ALONG WITH A
SEVERE THREAT. SATELLITE LOOPS INDICATE THAT PARTIAL CLEARING IS
DEVELOPING ACROSS MUCH OF PA THIS MORNING WITH CLOUDY SKIES
CONTINUING ACROSS NY STATE. 12Z BUF SOUNDING SHOWS A BIT OF A WARM
LAYER AT 700 MB AND ANOTHER WEAK WARM LAYER UP AROUND 500 MB... SO
OVERALL MID-LEVEL LAPSE RATES ARE NOT STEEP. HOWEVER MID-LEVEL
WINDS ARE RATHER STRONG WITH 40 KTS SHOWN FROM 700 TO 500 MB. SFC
DEW POINTS REMAIN IN THE MID 60S WITH A WEAK SURFACE TROUGH MOVING
IN FROM THE WEST. KEY FOR STRONG THUNDERSTORM DEVELOPMENT THIS
AFTERNOON WILL BE AMOUNT OF SUNSHINE AND DESTABILIZATION THAT
MIGHT OCCUR.
LATEST 12Z NAM IS STILL NOT VERY IMPRESSED WITH THE INSTABILITY
INDICATING CAPES OF 500 J/KG OR LESS. HOWEVER THE LATEST RAP AND
LAST NIGHTS GFS SHOW MORE INSTABILITY WITH CAPES UP NEAR OR JUST
OVER 1000 J/KG FROM THE SOUTHERN TIER OF NY SOUTH INTO PA. GIVEN
THAT CLEARING IS ALREADY OCCURRING ACROSS MUCH OF PA SUSPECT THAT
CAPES PROBABLY WILL AT LEAST APPROACH 1000 J/KG ACROSS NE PA THIS
AFTERNOON... AND SOME STRONG THUNDERSTORMS WILL PROBABLY DEVELOP.
FARTHER NORTH CLEARING IS LESS CERTAIN SO EXPECTING SHOWERS WITH
ISOLATED THUNDER. GIVEN MODERATELY MOIST ATMOSPHERE ANY STORM
COULD PRODUCE A QUICK INCH OF RAIN WHICH WOULD BE ENOUGH TO CAUSE
ISOLATED FLASH FLOODING... SO AM PLANNING ON EXTENDING THE WATCH
INTO EARLY THIS EVENING. ISOLATED SEVERE STORMS ALSO APPEAR TO BE
POSSIBLE THIS AFTERNOON ESPECIALLY IN NORTHEAST PA WHERE HEATING
WILL INCREASE THE INSTABILTY. PREVIOUS DISCUSSION BELOW.
630 AM UPDATE...MODERATE TO HEAVY RAIN NOW CONFINED TO NORTHERN
ONEIDA COUNTY AND THIS WILL LIFT NORTH OF THE AREA BY 8 AM. NEXT
BATCH OF SHOWERS/THUNDERSTORMS ASSOCIATED WITH FRONT END OF UPPER
LEVEL LOW NOW MOVING INTO WESTERN NEW YORK. THIS WILL BEGIN
SPREADING ACROSS WRN PTN OF FA BY MID MORNING. ONLY MINOR
ADJUSTMENTS NEEDED TO POP GRIDS.
AT 445 AM...SFC LOW PRES WAS LIFTING NORTH THROUGH EASTERN NEW
YORK WITH LOCAL RADARS SHOWING MODERATE TO HEAVY RAINFALL ACROSS
THE WESTERN MOHAWK VALLEY AND THE NORTHERN SUSQUEHANNA REGION. THE
HEAVY PRECIP ON THE BACK SIDE OF THIS LOW WILL GRADUALLY LIFT
NORTH OF THE REGION BY MID MORNING. FLASH FLOOD WARNINGS ARE
CURRENTLY IN EFFECT FOR MUCH OF THIS AREA.
FOR TODAY, UPPER LEVEL LOW OVER THE NRN GREAT LAKES WILL DROP
SOUTHEAST INTO THE EASTERN LAKES. MID LEVEL SHORT WAVES ROTATING
AROUND THE FEATURE WILL GENERATE MORE WIDESPREAD SHOWERS AND
THUNDERSTORMS FROM LATE THIS MORNING THROUGH THE AFTERNOON.
ATMOSPHERE REMAINS VERY MOIST WITH PWATS AROUND 1.50-1.75 INCHES,
THEREFORE ANY CONVECTION WILL HAVE THE POTENTIAL FOR TORRENTIAL
DOWNPOURS. MODEL SOUNDINGS INDICATE CAPE VALUES OF 500-1000 J/KG
WHICH WILL ENHANCE CONVECTIVE ACTIVITY UNDER THE UPPER LEVEL
FEATURE. WILL CONTINUE WITH FLASH FLOOD WATCH THROUGH THIS
AFTERNOON DUE TO ADDITIONAL CONVECTIVE RAINFALL FALLING ON SATURATED
SOILS ESPECIALLY OVER CENTRAL NEW YORK EAST OF INTERSTATE 81 AND
NORTHEAST PENNSYLVANIA. THERE IS THE POTENTIAL THAT A FEW STORMS
COULD BECOME SEVERE BUT ONE AGAIN LAPSE RATES, CAPE VALUES AND MID
LEVEL WIND FIELDS ARE VERY MARGINAL. IF SVR CONVECTION DOES OCCUR
IT WOULD MOST LIKELY BE OVER THE SOUTHERN CATSKILLS AND POCONOS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
TONIGHT THROUGH SUNDAY NIGHT...H5 UPPER LEVEL TROF WILL REMAIN
JUST WEST OF FA THROUGH SUNDAY NIGHT WITH AIRMASS REMAINING
FAIRLY MOIST. CONVECTIVE ACTIVITY WILL PERSIST THROUGH THE PERIOD
WITH THE MOST WIDESPREAD ACTIVITY OCCURRING DURING THE DAYLIGHT
HOURS ENHANCED BY DIURNAL HEATING. AIRMASS BECOMES EVEN MORE
MOISTURE LADEN SUNDAY/SUNDAY NIGHT AS FULL LATITUDE UPPER LEVEL
TROF BEGINS TO TAP MORE GULF MOISTURE. A VERY WET PERIOD AHEAD
WITH THE CONTINUED POTENTIAL FOR LOCALIZED HEAVY RAINS.
MAX TEMPS WILL GENERALLY RANGE FROM THE MID 70S INTO THE LOW 80S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
2 PM FRI UPDATE...
FOLLOWED WPC GUIDANCE. TEMPERATURES AND POPS ABOVE NORMAL. EURO
AND GFS SIMILAR WITH A HIGH AMPLITUDE STAGNANT PATTERN FOR THE
CONUS. DEEP TROF OVER THE OHIO VALLEY WILL PUT THE AREA IN A MOIST
AND WARM SW FLOW FOR MOST OF THE PERIOD. STALLED COASTAL FRONT
WITH LIKELY POPS IN THE SE MON NGT TO TUE THEN CHC POPS EVERY
DAY AFTER THAT. WITH DAILY DIURNAL SHOWERS HIGH TEMPERATURES
SHOULD ONLY MAKE THE LOWER 80S. THIS NEARLY STATIONARY TROF
UNUSUAL FOR JULY.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
130 PM EDT UPDATE...
ANOTHER CHALLENGING FORECAST FOR TODAY. TAF SITES HAVE MOSTLY
IMPROVED TO VFR. THE EXCEPTION IS KITH. WITH A LIGHT NW FLOW OFF
OF LAKE CAYUGA THEY HAVE HAD MOSTLY IFR CIGS AND MVFR VSBYS. THIS
SHOULD IMPROVE TO MVFR BY 20Z. ELSEWHERE VFR WITH POSSIBLE MVFR
CIGS IN SHOWERS. IN ANY HEAVY RAIN SHOWERS VSBYS COULD FALL TO
MVFR.
TONIGHT CLOUDS WILL REMAIN. KAVP SHOULD REMAIN VFR. IN NY VFR
CONDITIONS WILL FALL TO MVFR AROUND 6Z AND IFR AROUND 9Z.
IMPROVEMENT BACK TO VFR BY 14Z.
THIS AFTN SW TO NW WINDS AT 5 TO 10 KTS BECOMING LIGHT AND
VARIABLE TONIGHT. SW WINDS AT 5 TO 10 KTS SATURDAY.
OUTLOOK...SAT THROUGH TUE...
SAT THROUGH TUE... OCNL RESTRICTIONS ARE LIKELY EACH DAY...WITH
SHRA/TSRA IN THE VICINITY. THE MOST PERSISTENT RESTRICTIONS MAY
COME BY MON/MON NGT.
&&
.HYDROLOGY...
RECORD RIVER FLOODING OCCURRING AT ONEIDA ON ONEIDA CREEK. RIVER
FLOODING ON CHENANGO RIVER AT SHERBURNE. FORECASTED FLOODING ON
CHENANGO RIVER AT NORWICH AND GREENE AND THE SUSQUEHANNA RIVER AT
CONKLIN, VESTAL, WAVERLY/SAYRE.
FLASH FLOOD WATCH CONTINUES AND WAS EXTENDED TO 8 PM. MORE SLOW
MOVING THUNDERSTORMS COMING INTO THE CWA. AFTER FLOODING LAST
NIGHT IT WILL NOT TAKE MUCH MORE RAIN TO FLOOD. BASIN AVERAGES
UNDER AN INCH BUT LOCALIZED AMOUNTS OF OVER AN INCH POSSIBLE.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...FLASH FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR PAZ038>040-
043-044-047-048-072.
NY...FLASH FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR NYZ009-
015>018-022>025-036-037-044>046-055>057-062.
&&
$$
SYNOPSIS...RRM
NEAR TERM...MSE/RRM
SHORT TERM...RRM
LONG TERM...TAC
AVIATION...TAC
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS RALEIGH NC
300 PM EDT FRI JUN 28 2013
.SYNOPSIS...
A WARM AND HUMID AIR MASS COMBINED WITH A PERSISTENT TROUGH OF LOW
PRESSURE OVER THE REGION WILL RESULT IN A GOOD CHANCE OF SHOWERS AND
THUNDERSTORMS EACH DAY THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH SATURDAY NIGHT/...
AS OF 245 PM FRIDAY...
THROUGH TONIGHT: LITTLE DOUBT THAT MOST IF NOT ALL OF THE AREA WILL
SEE SHOWERS/STORMS IN THE NEXT 18 HOURS. ACCORDING TO CURRENT
MESOANALYSES WE CONTINUE TO DESTABILIZE WITH MLCAPE ALREADY UP TO
1500-2500 J/KG AND MUCAPE AROUND 3000 J/KG. A BROKEN LINE OF SHOWERS
AND STORMS HAS FORMED OVER SOUTH-CENTRAL AND SW VA INTO THE NC
MOUNTAINS... AND THIS CONVECTION IS ON TRACK TO DROP ESE THROUGH
CENTRAL NC FROM MID AFTERNOON THROUGH THE EVENING. AS EXPECTED...
DEEP LAYER SHEAR CONTINUES TO IMPROVE TO 30-35 KTS... SUPPORTIVE OF
ORGANIZED CONVECTION... PARTICULARLY AS THIS INCOMING LINE FEEDS ON
A HIGHLY MOIST AND BUOYANT BOUNDARY LAYER WITH TEMPS NEAR 90 (THANKS
TO PLENTY OF HEATING THUS FAR) AND DEW POINTS IN THE LOW-MID 70S.
EXPECT CONVECTION TO BECOME MORE NUMEROUS AND STRENGTHEN AS IT TAPS
INTO THIS JUICIER AIR ALONG AND EAST OF THE HIGHWAY 1 CORRIDOR.
RECENT HRRR RUNS DEPICTED THIS SCENARIO FAIRLY WELL... BRINGING
SCATTERED STORMS INTO THE TRIAD TOWARD 19-20Z WHICH THEN CONGEAL
INTO AN ORGANIZED BAND OF STORM CLUSTERS HEADING EASTWARD THROUGH
04Z. STILL APPEARS THAT SEVERE WIND GUSTS WILL BE THE BIGGEST SEVERE
THREAT LATE TODAY INTO TONIGHT GIVEN THAT WE HAVE SOME DRIER AIR NOT
FAR OFF THE SURFACE AND DECENT D-CAPE AT OR OVER 800 J/KG. THE -10C
TO -30C CAPE IS NOT ESPECIALLY LARGE BUT HAS RISEN A BIT IN RECENT
HOURS TO NEAR 500 J/KG EAST OF THE HIGHER TERRAIN... THUS LARGE HAIL
REMAINS POSSIBLE BUT IS A SECONDARY THREAT. WILL CONTINUE TO TREND
POPS DOWN AND OUT GRADUALLY WEST TO EAST AFTER MIDNIGHT WITH LOSS OF
HEATING. FOG/STRATUS HAS BEEN TOUGH TO FORECAST THE LAST FEW DAYS
BUT WILL LEAN TOWARD PERSISTENCE... WITH BETTER COVERAGE EAST OF
HIGHWAY 1 WITHIN A VERY LIGHT SW FLOW.
FOR SATURDAY/SATURDAY NIGHT: CONTINUED WARM... DAMP... AND HUMID.
WE`LL REMAIN BENEATH CLIMATOLOGICALLY FAST CYCLONIC MID LEVEL FLOW
HEADING INTO THE WEEKEND. MODELS SHOW THE SURFACE TROUGH SHIFTING TO
THE COASTAL PLAIN SATURDAY MORNING WITH MARKEDLY LOWER SURFACE
THETA-E VALUES PUSHING INTO THE WRN FORECAST AREA. EXPECT TO SEE
SOME LINGERING PATCHY SHOWERS ALONG WITH AREAS OF STRATUS OVER THE
COASTAL PLAIN SATURDAY MORNING... BUT WEAK TO ABSENT DYNAMIC FORCING
FOR ASCENT AND TYPICALLY LOWER INSTABILITY AND LINGERING CINH THAT
TIME OF DAY WILL LIMIT COVERAGE/STRENGTH OF ANY CONVECTION DURING
THE MORNING... AND THE WRN PIEDMONT SHOULD REMAIN DRY THROUGH
MIDDAY. WITH THE INJECTION OF ENERGY DOWN ITS WEST SIDE... THE MID
LEVEL TROUGH IS EXPECTED TO DIG STRONGLY DOWN LAKE MICHIGAN INTO IN
AND THE WRN OH VALLEY THROUGH SATURDAY NIGHT... CAUSING A BACKING OF
MID LEVEL WINDS OVER NC TO A MORE SOUTHERLY DIRECTION AND A GRADUAL
STRENGTHENING AND BUILDING OF THE ATLANTIC ANTICYCLONE WESTWARD
TOWARD COASTAL NC. THIS WILL EFFECTIVELY LEAD TO DISSIPATION OF THE
ERN NC SURFACE TROUGH WHILE THE MORE SUBSTANTIAL FRONTAL ZONE
STRENGTHENS TO OUR WEST AND HIGH PW VALUES REBOUND BACK WESTWARD
THROUGH CENTRAL NC WITH AN ATTENDING RESURGENCE OF HIGHER 850 MB
THETA-E. THE NAM/GFS HANDLE THEIR PRECIP FIELDS DIFFERENTLY WITH THE
NAM HOLDING WIDESPREAD CONVECTION TO OUR EAST AND WEST UNTIL VERY
LATE SATURDAY NIGHT... WHILE THE GFS DEVELOPS CONVECTION WITH
HEATING SATURDAY AFTERNOON ESPECIALLY ALONG THE HIGHWAY 1
CORRIDOR... WHICH THEN PERSISTS THROUGH THE NIGHT AS THE 2+ INCH
PRECIP WATER VALUES SPREAD FROM THE COAST WESTWARD THROUGH ALL OF
CENTRAL NC. THE GFS`S PATTERN LOOKS TO BE A MORE REASONABLE
SCENARIO... WITH MORE SCATTERED DISCRETE CELLS IN THE FAR WRN
PIEDMONT (WHERE SURFACE DEW POINTS AND HENCE INSTABILITY WILL LIKELY
BE A BIT LOWER) TRENDING TO NUMEROUS CLUSTERS OF MULTICELLS ROUGHLY
EAST OF A LINE FROM ROXBORO TO SILER CITY TO WADESBORO (ATTENDING
THE GREATER INSTABILITY AND PW). THE BACKED STEERING FLOW AND
EXPECTED ORIENTATION OF CONVECTIVE BANDS WILL BRING ABOUT A CONCERN
FOR TRAINING ECHOES AND LOCALIZED URBAN AND STREET FLOODING AND
SWOLLEN CREEKS STARTING SATURDAY... ESPECIALLY CONSIDERING THE
IMPROVING UPPER DIVERGENCE OVER CENTRAL/ERN NC IN THE RIGHT ENTRANCE
REGION OF THE SOUTHERLY JET TO OUR NNW. AFTER MUCH COORDINATION AND
DISCUSSION... WILL NOT GO WITH A FLASH FLOOD WATCH AS YET... AS
WIDESPREAD HEAVY RAIN HAS YET TO MATERIALIZE IN THE ERN
PIEDMONT/SANDHILLS/COASTAL PLAIN WHERE THE MORE SANDY SOIL AND
FLATTER TERRAIN RESULTS IN SLOWER RUNOFF... BUT URBAN AREAS WILL
REMAIN VULNERABLE TO SOME FLOODING. WE WILL CONTINUE TO RE-EVALUATE
AND CONSIDER THIS RISK AS WE HEAD THROUGH THE WEEKEND. WILL HAVE A
GOOD CHANCE OF SHOWERS/STORMS WEST SATURDAY AFTERNOON/NIGHT WITH
LIKELY POPS ALONG/EAST OF THE AFOREMENTIONED LINE COVERING THE
CENTRAL/ERN CWA. DEEP LAYER SHEAR IS NOT TREMENDOUS BUT DOES IMPROVE
FURTHER TO 25-35 KTS... ALTHOUGH MODEL MLCAPE VALUES ONLY PEAK AT
800-1500 J/KG SATURDAY AFTERNOON ALONG/EAST OF HIGHWAY 1...
SUGGESTING PERHAPS A MORE MOIST-ADIABATIC PROFILE THAN WE`VE SEEN
LATELY. POTENTIALLY WEAKER UPDRAFTS ESPECIALLY ALOFT COULD LOWER THE
RISK OF SEVERE STORMS... BUT AGAIN THE DEEP WARM LAYER (LCL TO
FREEZING DEPTH NEAR 4 KM) AND PW NEAR 2 INCHES (WHICH IS NEARLY 2
STANDARD DEVIATIONS ABOVE NORMAL) SUPPORT A HEAVY RAIN THREAT WITH
WARM RAIN PROCESSES DOMINATING. HIGHS 87-91. LOWS 68-72. -GIH
&&
.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 245 PM FRIDAY...
THE WELL-ADVERTISED DEVELOPING TROUGH ALOFT WILL HAVE BECOME
STRONGLY AMPLIFIED AND ESTABLISHED OVER THE TN VALLEY THIS
PERIOD...BETWEEN A PAIR OF ANOMALOUSLY STRONG RIDGES OVER WESTERN N.
AMERICA AND THE WESTERN N. ATLANTIC. WHILE LOW LEVEL CONVERGENCE IN
ASSOCIATION WITH A LEE TROUGH/WEAK FRONT WILL HAVE DIMINISHED FROM
PREVIOUS DAYS...THE PATTERN OF PERTURBED SW TO SSW DEEP LAYER FLOW
WILL DRIVE NUMEROUS TO WIDESPREAD SHOWERS/STORMS...AMIDST A DEEP
MOIST AXIS CHARACTERIZED BY PRECIPITABLE WATER VALUES AROUND TWO
INCHES...SUNDAY AND LIKELY THROUGHOUT SUNDAY NIGHT. DEEP LAYER SHEAR
ON THE ORDER OF 25-30 KTS...TO PERHAPS 35 KTS OVER THE NW
PIEDMONT...WILL SUPPORT PRIMARILY MULTI-CELL BANDS CAPABLE OF
PRODUCING WET MICROBURSTS...AND TO A GREATER EXTENT LOCALIZED
FLOODING OWING THE ANOMALOUSLY HIGH PW/S. HIGHS GENERALLY IN THE MID
80S...AND LOWER 70S FOR LOWS.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 255 PM FRIDAY...
CONTINUED...IF NOT INCREASINGLY...WET. THE LARGE SCALE
RIDGE/TROUGH/RIDGE CONFIGURATION ACROSS NOAM WILL GRADUALLY
RETROGRESS...WITH THE TROUGH DRIFTING WESTWARD INTO THE MS
VALLEY...THROUGH MID-LATE WEEK. THE PRESENCE AND PERSISTENCE OF THE
TROUGH WILL KEEP MUCH OF THE EASTERN US...INCLUDING CENTRAL NC...IN
A PATTERN OF PERTURBED AND DEEPLY MOIST SW TO SSW FLOW ALOFT -
FAVORABLE FOR ABOVE AVERAGE PRECIPITATION CHANCES...PARTICULARLY
THROUGH WEDNESDAY. THE PROLONGED STORMY PERIOD WILL FAVOR AN
INCREASING RISK OF FLOODING WITH EACH DAY THAT PASSES...WITH
OTHERWISE AN OCCASIONAL PRECIPITATION-LOADED WET MICROBURST FROM
LOOSELY ORGANIZED MULTI-CELL STORM MODES DRIVEN BY GENERALLY 20-25
KTS OF MID LEVEL FLOW. ASIDE FROM THE 00Z/28TH ECMWF...THE CONSENSUS
OF MEDIUM RANGE GUIDANCE...INCLUDING THE 00Z ECMWF ENSEMBLE
MEAN...INDICATES THE PATTERN RETROGRESSION WILL ALLOW THE WESTERN
ATLANTIC SUB-TROPICAL RIDGING TO EXPAND WESTWARD SUFFICIENTLY TO
LESSEN PRECIPITATION CHANCES/COVERAGE - FROM NUMEROUS/WIDESPREAD TO
SCATTERED - OVER EASTERN NC...INCLUDING THE RAH COASTAL PLAIN...BY
MID TO LATE WEEK. HIGHS MOSTLY IN THE MIDDLE 80S...WITH LOWS 70 TO
75.
&&
.AVIATION /18Z THURSDAY THROUGH WEDNESDAY/...
AS OF 135 PM FRIDAY...
THIS MORNING`S IFR STRATUS AFFECTING RDU/RWI/FAY HAS SHIFTED
EASTWARD AND MIXED OUT... AND VFR CONDITIONS WILL DOMINATE THIS
AFTERNOON. BUT WE REMAIN IN A WARM... HUMID... AND UNSETTLED PATTERN
OVER CENTRAL NC... WITH A HIGH PROBABILITY OF STORMS PARTICULARLY AT
RDU/RWI/FAY MID-LATE AFTERNOON THROUGH TONIGHT. LOCAL TORRENTIAL
DOWNPOURS WITH BRIEF IFR/LIFR CONDITIONS ARE POSSIBLE WITH THESE
SHOWERS AND STORMS... ALONG WITH THE POTENTIAL FOR SURFACE WIND
GUSTS OVER 40 MPH. SCATTERED STORMS ARE EXPECTED NEAR INT/GSO AFTER
19Z... SPREADING EASTWARD TOWARD RDU/RWI/FAY AFTER 21Z AND BECOMING
NUMEROUS. STORM CHANCES WILL PERSIST IN LATE EVENING AT
RDU/RWI/FAY... TAPERING TO LIGHTER AND MORE PATCHY SHOWERS LATE
TONIGHT. BASED ON THE PERSISTENCE OF THIS PATTERN... AREAS OF
IFR/LIFR STRATUS ARE POSSIBLE AFTER 07Z TONIGHT AT RDU/RWI/FAY...
BUT ONCE AGAIN THE MODELS ARE PRESENTING CONFLICTING GUIDANCE
REGARDING THIS THREAT... SO CONFIDENCE IN OCCURRENCE OF A
PREDOMINANT IFR/LIFR CIG IS LOW. ANY SUCH STRATUS WOULD LIFT BY 14Z
SATURDAY MORNING... AND VFR CONDITIONS WOULD THEN HOLD THROUGH 18Z.
LOOKING BEYOND 18Z SATURDAY... SHOWERS/STORMS AND ATTENDANT MVFR OR
IFR CONDITIONS ARE EXPECTED TO BECOME MORE NUMEROUS SATURDAY
AFTERNOON INTO THE NIGHT... SO EXPECT INCREASINGLY POTENTIAL FOR
ADVERSE AVIATION CONDITIONS... ESPECIALLY AT RDU/RWI/FAY. WITH
MINIMAL CHANGE IN THE OVERALL PATTERN OVER THE CONUS... THE RISK FOR
DAILY NUMEROUS SUB-VFR SHOWERS AND STORMS (PRIMARILY FROM MID
AFTERNOON THROUGH MIDNIGHT) AND SHALLOW EARLY-MORNING IFR STRATUS IS
EXPECTED TO PERSIST INTO THE MIDDLE OF NEXT WEEK. -GIH
&&
.EQUIPMENT...
KRAX WSR-88D IS BACK IN OPERATIONAL SERVICE.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...MWS
LONG TERM...MWS
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
245 PM EDT FRI JUN 28 2013
.SYNOPSIS...
A WARM AND HUMID AIR MASS COMBINED WITH A PERSISTENT TROUGH OF LOW
PRESSURE OVER THE REGION WILL RESULT IN A GOOD CHANCE OF SHOWERS AND
THUNDERSTORMS EACH DAY THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH SATURDAY NIGHT/...
AS OF 245 PM FRIDAY...
THROUGH TONIGHT: LITTLE DOUBT THAT MOST IF NOT ALL OF THE AREA WILL
SEE SHOWERS/STORMS IN THE NEXT 18 HOURS. ACCORDING TO CURRENT
MESOANALYSES WE CONTINUE TO DESTABILIZE WITH MLCAPE ALREADY UP TO
1500-2500 J/KG AND MUCAPE AROUND 3000 J/KG. A BROKEN LINE OF SHOWERS
AND STORMS HAS FORMED OVER SOUTH-CENTRAL AND SW VA INTO THE NC
MOUNTAINS... AND THIS CONVECTION IS ON TRACK TO DROP ESE THROUGH
CENTRAL NC FROM MID AFTERNOON THROUGH THE EVENING. AS EXPECTED...
DEEP LAYER SHEAR CONTINUES TO IMPROVE TO 30-35 KTS... SUPPORTIVE OF
ORGANIZED CONVECTION... PARTICULARLY AS THIS INCOMING LINE FEEDS ON
A HIGHLY MOIST AND BUOYANT BOUNDARY LAYER WITH TEMPS NEAR 90 (THANKS
TO PLENTY OF HEATING THUS FAR) AND DEW POINTS IN THE LOW-MID 70S.
EXPECT CONVECTION TO BECOME MORE NUMEROUS AND STRENGTHEN AS IT TAPS
INTO THIS JUICIER AIR ALONG AND EAST OF THE HIGHWAY 1 CORRIDOR.
RECENT HRRR RUNS DEPICTED THIS SCENARIO FAIRLY WELL... BRINGING
SCATTERED STORMS INTO THE TRIAD TOWARD 19-20Z WHICH THEN CONGEAL
INTO AN ORGANIZED BAND OF STORM CLUSTERS HEADING EASTWARD THROUGH
04Z. STILL APPEARS THAT SEVERE WIND GUSTS WILL BE THE BIGGEST SEVERE
THREAT LATE TODAY INTO TONIGHT GIVEN THAT WE HAVE SOME DRIER AIR NOT
FAR OFF THE SURFACE AND DECENT D-CAPE AT OR OVER 800 J/KG. THE -10C
TO -30C CAPE IS NOT ESPECIALLY LARGE BUT HAS RISEN A BIT IN RECENT
HOURS TO NEAR 500 J/KG EAST OF THE HIGHER TERRAIN... THUS LARGE HAIL
REMAINS POSSIBLE BUT IS A SECONDARY THREAT. WILL CONTINUE TO TREND
POPS DOWN AND OUT GRADUALLY WEST TO EAST AFTER MIDNIGHT WITH LOSS OF
HEATING. FOG/STRATUS HAS BEEN TOUGH TO FORECAST THE LAST FEW DAYS
BUT WILL LEAN TOWARD PERSISTENCE... WITH BETTER COVERAGE EAST OF
HIGHWAY 1 WITHIN A VERY LIGHT SW FLOW.
FOR SATURDAY/SATURDAY NIGHT: CONTINUED WARM... DAMP... AND HUMID.
WE`LL REMAIN BENEATH CLIMATOLOGICALLY FAST CYCLONIC MID LEVEL FLOW
HEADING INTO THE WEEKEND. MODELS SHOW THE SURFACE TROUGH SHIFTING TO
THE COASTAL PLAIN SATURDAY MORNING WITH MARKEDLY LOWER SURFACE
THETA-E VALUES PUSHING INTO THE WRN FORECAST AREA. EXPECT TO SEE
SOME LINGERING PATCHY SHOWERS ALONG WITH AREAS OF STRATUS OVER THE
COASTAL PLAIN SATURDAY MORNING... BUT WEAK TO ABSENT DYNAMIC FORCING
FOR ASCENT AND TYPICALLY LOWER INSTABILITY AND LINGERING CINH THAT
TIME OF DAY WILL LIMIT COVERAGE/STRENGTH OF ANY CONVECTION DURING
THE MORNING... AND THE WRN PIEDMONT SHOULD REMAIN DRY THROUGH
MIDDAY. WITH THE INJECTION OF ENERGY DOWN ITS WEST SIDE... THE MID
LEVEL TROUGH IS EXPECTED TO DIG STRONGLY DOWN LAKE MICHIGAN INTO IN
AND THE WRN OH VALLEY THROUGH SATURDAY NIGHT... CAUSING A BACKING OF
MID LEVEL WINDS OVER NC TO A MORE SOUTHERLY DIRECTION AND A GRADUAL
STRENGTHENING AND BUILDING OF THE ATLANTIC ANTICYCLONE WESTWARD
TOWARD COASTAL NC. THIS WILL EFFECTIVELY LEAD TO DISSIPATION OF THE
ERN NC SURFACE TROUGH WHILE THE MORE SUBSTANTIAL FRONTAL ZONE
STRENGTHENS TO OUR WEST AND HIGH PW VALUES REBOUND BACK WESTWARD
THROUGH CENTRAL NC WITH AN ATTENDING RESURGENCE OF HIGHER 850 MB
THETA-E. THE NAM/GFS HANDLE THEIR PRECIP FIELDS DIFFERENTLY WITH THE
NAM HOLDING WIDESPREAD CONVECTION TO OUR EAST AND WEST UNTIL VERY
LATE SATURDAY NIGHT... WHILE THE GFS DEVELOPS CONVECTION WITH
HEATING SATURDAY AFTERNOON ESPECIALLY ALONG THE HIGHWAY 1
CORRIDOR... WHICH THEN PERSISTS THROUGH THE NIGHT AS THE 2+ INCH
PRECIP WATER VALUES SPREAD FROM THE COAST WESTWARD THROUGH ALL OF
CENTRAL NC. THE GFS`S PATTERN LOOKS TO BE A MORE REASONABLE
SCENARIO... WITH MORE SCATTERED DISCRETE CELLS IN THE FAR WRN
PIEDMONT (WHERE SURFACE DEW POINTS AND HENCE INSTABILITY WILL LIKELY
BE A BIT LOWER) TRENDING TO NUMEROUS CLUSTERS OF MULTICELLS ROUGHLY
EAST OF A LINE FROM ROXBORO TO SILER CITY TO WADESBORO (ATTENDING
THE GREATER INSTABILITY AND PW). THE BACKED STEERING FLOW AND
EXPECTED ORIENTATION OF CONVECTIVE BANDS WILL BRING ABOUT A CONCERN
FOR TRAINING ECHOES AND LOCALIZED URBAN AND STREET FLOODING AND
SWOLLEN CREEKS STARTING SATURDAY... ESPECIALLY CONSIDERING THE
IMPROVING UPPER DIVERGENCE OVER CENTRAL/ERN NC IN THE RIGHT ENTRANCE
REGION OF THE SOUTHERLY JET TO OUR NNW. AFTER MUCH COORDINATION AND
DISCUSSION... WILL NOT GO WITH A FLASH FLOOD WATCH AS YET... AS
WIDESPREAD HEAVY RAIN HAS YET TO MATERIALIZE IN THE ERN
PIEDMONT/SANDHILLS/COASTAL PLAIN WHERE THE MORE SANDY SOIL AND
FLATTER TERRAIN RESULTS IN SLOWER RUNOFF... BUT URBAN AREAS WILL
REMAIN VULNERABLE TO SOME FLOODING. WE WILL CONTINUE TO RE-EVALUATE
AND CONSIDER THIS RISK AS WE HEAD THROUGH THE WEEKEND. WILL HAVE A
GOOD CHANCE OF SHOWERS/STORMS WEST SATURDAY AFTERNOON/NIGHT WITH
LIKELY POPS ALONG/EAST OF THE AFOREMENTIONED LINE COVERING THE
CENTRAL/ERN CWA. DEEP LAYER SHEAR IS NOT TREMENDOUS BUT DOES IMPROVE
FURTHER TO 25-35 KTS... ALTHOUGH MODEL MLCAPE VALUES ONLY PEAK AT
800-1500 J/KG SATURDAY AFTERNOON ALONG/EAST OF HIGHWAY 1...
SUGGESTING PERHAPS A MORE MOIST-ADIABATIC PROFILE THAN WE`VE SEEN
LATELY. POTENTIALLY WEAKER UPDRAFTS ESPECIALLY ALOFT COULD LOWER THE
RISK OF SEVERE STORMS... BUT AGAIN THE DEEP WARM LAYER (LCL TO
FREEZING DEPTH NEAR 4 KM) AND PW NEAR 2 INCHES (WHICH IS NEARLY 2
STANDARD DEVIATIONS ABOVE NORMAL) SUPPORT A HEAVY RAIN THREAT WITH
WARM RAIN PROCESSES DOMINATING. HIGHS 87-91. LOWS 68-72. -GIH
&&
.SHORT TERM / /...
AS OF 300 AM FRIDAY...
TO BE UPDATED.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 300 AM FRIDAY...
AN UNUSUALLY AMPLIFIED UPPER LEVEL PATTERN WILL PERSIST THROUGH MUCH
OF THE PERIOD AS RIDGES DOMINATE WEST OF THE ROCKIES (EXTENDING UP
INTO CANADA) AND ACROSS THE WESTERN ATLANTIC...WITH A DEEP TROUGH
SANDWICHED IN THE MIDDLE. THIS TROUGH WILL GRADUALLY RETROGRADE
THROUGH THE PERIOD...NEVERTHELESS LEAVING CENTRAL NC WITHIN A
PERSISTENT DEEP SOUTHWESTERLY FLOW. AS A RESULT...NUMEROUS
DISTURBANCES ALOFT WILL MOVE ACROSS THE AREA AND WITH MOISTURE
REMAINING HIGH (BETWEEN 1.75-2 INCHES)...UNSETTLED WEATHER WILL
CONTINUE THROUGH THE ENTIRE LONG TERM PERIOD (IF NOT LONGER)...WITH
ABOVE NORMAL CHANCES OF SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS EXPECTED EACH DAY (MOSTLY DIURNALLY DRIVEN). AS THE
UPPER LEVEL TROUGH RETROGRADES...THE RIDGE OVER THE WESTERN ATLANTIC
WILL PUSH WESTWARD...THEREFORE EVENTUALLY EXERTING SOME MORE
INFLUENCE OVER THE REGION BY THE MIDDLE/LATTER PORTION OF THE WEEK.
THIS IS WHEN WE MAY START SEEING A DECREASE IN PRECIP COVERAGE...
ESPECIALLY OVER EASTERN NC.
OTHERWISE...WITH THE INCREASED FLOW ALOFT...DECENT DEEP LAYER SHEAR
WILL PERSIST OVER THE AREA AND THEREFORE WE SHOULD SEE MORE IN THE
WAY OF ORGANIZED CONVECTION. THIS MAY RESULT IN SOME STRONG TO
SEVERE STORMS. ANOTHER SIGNIFICANT WEATHER THREAT WILL BE THE
INCREASING FLOODING RISK AS THE AREA REMAINS IN THIS EXTENDED WET
PATTERN. DAYTIME HIGHS WILL GENERALLY BE BELOW NORMAL THROUGH THE
PERIOD...WITH MOSTLY MID 80S EXPECTED. OVERNIGHT LOWS WILL MOSTLY BE
IN THE LOWER 70S.
&&
.AVIATION /18Z THURSDAY THROUGH WEDNESDAY/...
AS OF 135 PM FRIDAY...
THIS MORNING`S IFR STRATUS AFFECTING RDU/RWI/FAY HAS SHIFTED
EASTWARD AND MIXED OUT... AND VFR CONDITIONS WILL DOMINATE THIS
AFTERNOON. BUT WE REMAIN IN A WARM... HUMID... AND UNSETTLED PATTERN
OVER CENTRAL NC... WITH A HIGH PROBABILITY OF STORMS PARTICULARLY AT
RDU/RWI/FAY MID-LATE AFTERNOON THROUGH TONIGHT. LOCAL TORRENTIAL
DOWNPOURS WITH BRIEF IFR/LIFR CONDITIONS ARE POSSIBLE WITH THESE
SHOWERS AND STORMS... ALONG WITH THE POTENTIAL FOR SURFACE WIND
GUSTS OVER 40 MPH. SCATTERED STORMS ARE EXPECTED NEAR INT/GSO AFTER
19Z... SPREADING EASTWARD TOWARD RDU/RWI/FAY AFTER 21Z AND BECOMING
NUMEROUS. STORM CHANCES WILL PERSIST IN LATE EVENING AT
RDU/RWI/FAY... TAPERING TO LIGHTER AND MORE PATCHY SHOWERS LATE
TONIGHT. BASED ON THE PERSISTENCE OF THIS PATTERN... AREAS OF
IFR/LIFR STRATUS ARE POSSIBLE AFTER 07Z TONIGHT AT RDU/RWI/FAY...
BUT ONCE AGAIN THE MODELS ARE PRESENTING CONFLICTING GUIDANCE
REGARDING THIS THREAT... SO CONFIDENCE IN OCCURRENCE OF A
PREDOMINANT IFR/LIFR CIG IS LOW. ANY SUCH STRATUS WOULD LIFT BY 14Z
SATURDAY MORNING... AND VFR CONDITIONS WOULD THEN HOLD THROUGH 18Z.
LOOKING BEYOND 18Z SATURDAY... SHOWERS/STORMS AND ATTENDANT MVFR OR
IFR CONDITIONS ARE EXPECTED TO BECOME MORE NUMEROUS SATURDAY
AFTERNOON INTO THE NIGHT... SO EXPECT INCREASINGLY POTENTIAL FOR
ADVERSE AVIATION CONDITIONS... ESPECIALLY AT RDU/RWI/FAY. WITH
MINIMAL CHANGE IN THE OVERALL PATTERN OVER THE CONUS... THE RISK FOR
DAILY NUMEROUS SUB-VFR SHOWERS AND STORMS (PRIMARILY FROM MID
AFTERNOON THROUGH MIDNIGHT) AND SHALLOW EARLY-MORNING IFR STRATUS IS
EXPECTED TO PERSIST INTO THE MIDDLE OF NEXT WEEK. -GIH
&&
.EQUIPMENT...
KRAX WSR-88D WILL REMAIN DOWN OR IN DEGRADED MODE THROUGH MID
AFTERNOON TODAY. KRAX HAS BEEN IN A SEVERELY DEGRADED MODE FOR
SEVERAL DAYS... AND THE NEEDED REPAIRS WERE DEEMED TO BE CRITICAL.
THE TEAM OF TECHNICIANS ARE MAKING THESE REPAIRS AS QUICKLY AS
POSSIBLE... AND IS WORKING HARD TO RETURN THE RADAR TO NORMAL
SERVICE THIS AFTERNOON. WE APOLOGIZE FOR THE INCONVENIENCE. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...CBL
LONG TERM...KRR
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
135 PM EDT FRI JUN 28 2013
.SYNOPSIS...
A WARM AND HUMID AIR MASS COMBINED WITH A PERSISTENT TROUGH OF LOW
PRESSURE OVER THE REGION WILL RESULT IN A GOOD CHANCE OF SHOWERS AND
THUNDERSTORMS EACH DAY THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1040 AM FRIDAY...
LITTLE DOUBT THAT MOST OF THE AREA WILL SEE SHOWERS/STORMS SOMETIME
IN THE NEXT 18 HOURS... ALTHOUGH IT LOOKS LIKE WE MAY SEE A SLIGHT
DELAY IN THE MORE ORGANIZED CONVECTION UNTIL LATER IN THE DAY.
ACCORDING TO CURRENT MESOANALYSES WE ARE SLOWLY DESTABILIZING BUT
WITH A LOT OF REMAINING CINH. LATEST SATELLITE IMAGERY SHOWS THAT
MUCH OF THE MORNING STRATUS IN THE COASTAL PLAIN IS SLOWLY MOVING
OUT TO THE EAST... WHILE THE WRN SECTIONS ARE SEEING HIGH THIN
CLOUDS ASSOCIATED WITH THE NOW-DYING MCS DIVING FROM MEMPHIS INTO
MS/AL. OVERNIGHT RUNS OF THE RAP MODEL HAVE HAD A DIFFICULT TIME
WITH THE MCV TO OUR WEST... TRACKING IT EASTWARD THROUGH THE
CAROLINAS WHEN TRAJECTORIES AND OBSERVATIONS SUGGEST THAT IT WILL
TAKE A MORE SRN ROUTE THROUGH AL AND PERHAPS GA. WITH THIS FEATURE
LIKELY SLIDING TO OUR SOUTH... WHILE ANOTHER AREA OF ENHANCED
MID/HIGH-LEVEL FORCING FOR ASCENT TRACKS UP THROUGH PA... NC COULD
BE LEFT BENEATH A RELATIVE MINIMUM IN TERMS OF LARGE SCALE DYNAMIC
FORCING. THAT SAID... DEEP LAYER SHEAR IS EXPECTED TO STEADILY
INCREASE THROUGH THE DAY -- ESPECIALLY INTO THE EVENING -- AND WITH
THE DEARTH OF MORNING CLOUD COVER LEADING TO GOOD HEATING (TEMPS ARE
RUNNING A FEW DEGREES COOLER THAN YESTERDAY IN THE SOUTHEAST BUT 1-7
DEGREES WARMER THAN THIS TIME THURSDAY OVER THE REST OF CENTRAL NC)
AND MODELS PROJECTING 1500-2500 J/KG OF MLCAPE OVER ALL BUT THE NW
CWA BY MID AFTERNOON... SEE NO REASON TO THINK THAT WE WON`T SEE
INCREASING STORMS (IN NUMBER AND INTENSITY) HEADING THROUGH THE
MID-LATE AFTERNOON AND THROUGH THE EVENING. THE LATEST HRRR RUN
DEPICTS THIS SCENARIO QUITE WELL... BRINGING SCATTERED STORMS INTO
THE TRIAD TOWARD 19-20Z THEN CONGEALING INTO AN ORGANIZED BAND OF
STORM CLUSTERS HEADING EASTWARD THROUGH 04Z. STILL APPEARS THAT
SEVERE WIND GUSTS WILL BE THE BIGGEST THREAT LATE TODAY INTO TONIGHT
GIVEN THAT WE HAVE SOME DRY AIR NOT FAR OFF THE SURFACE. THE -10C TO
-30C CAPE IS QUITE LOW THIS MORNING AND DON`T EXPECT THAT TO CHANGE
MUCH WITH ONLY MINIMAL COOLING ALOFT AND NO APPARENT OPPORTUNITY FOR
GOOD MOISTURE FLUX IN THIS MIXED PHASE REGION... THUS THE RISK OF
LARGE HAIL SHOULD BE SECONDARY. IT IS INTERESTING HOW VERY DRY THE
12Z GSO SOUNDING WAS... WITH A PW OF 1.02 INCHES... MUCH LOWER THAN
IN PAST DAYS AND A BIT OF AN OUTLIER COMPARED TO SURROUNDING UPPER
AIR PLOTS. IT ALSO DEPARTS QUITE A BIT FROM THE PW NOTED ON TPW
BLENDED IMAGERY (AROUND 1.4 INCHES IN THE TRIAD). MODELS DO SHOW A
REMOISTENING OF THE COLUMN HERE THIS AFTERNOON... TOUGH TO BELIEVE
CONSIDERING THE OBSERVED UPPER-AIR DATA UPSTREAM THIS MORNING AND
THE LOW DEW POINTS IN THE TRIAD. WILL LEAVE IN GOOD CHANCE POPS HERE
FOR NOW GIVEN THE IMPROVING BULK SHEAR THROUGH THE DAY... ALTHOUGH
WE SHOULD SEE A RELATIVE MINIMUM IN COVERAGE IN THE TRIAD. LITTLE
CHANGE IN HIGHS WITH TEMP TRENDS SUPPORTING READINGS OF 89-94. WILL
CONTINUE TO TREND POPS DOWN AND OUT WEST TO EAST ESPECIALLY AFTER
MIDNIGHT WITH LOSS OF HEATING. FOG/STRATUS HAS BEEN TOUGH TO
FORECAST THE LAST FEW DAYS BUT WILL LEAN TOWARD PERSISTENCE... WITH
BETTER COVERAGE EAST OF HIGHWAY 1 WITHIN A VERY LIGHT SW FLOW. -GIH
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
AS OF 300 AM FRIDAY...
AS THE UPPER TROUGH CONTINUES TO DEEPEN...MID TO UPPER LEVEL FLOW
WILL BECOME SWLY AND WE WILL HAVE TO BE CONCERN WITH SHORTWAVE
IMPULSES FROM THE SW AS OPPOSE TO THE W-NW FROM RECENT DAYS. ANOTHER
IMPORTANT DIFFERENCE TO NOTE IS HOW MODELS ARE HANDLING THE
MEANDERING SURFACE TROUGH/FRONT WITH BOTH THE NAM AND GFS ADVECTING
CONSIDERABLY LOWER THETA-E AIR INTO THE LOW-LEVELS...WHICH
EFFECTIVELY LESSENS CAPE OVER THE WESTERN PIEDMONT. THIS WOULD
POTENTIALLY CONFINE THE BEST CONVECTIVE ACTIVITY TO EASTERN NC WITH
LOWER PRECIP PROBABILITIES THAN CURRENTLY FORECASTING ACROSS THE
WESTERN AND POSSIBLY CENTRAL PIEDMONT.
FOR STORMS THAT DO DEVELOP...THE MODEST MID-LEVEL WIND FIELD
OF 30 TO 35KTS AND STRONG DESTABILIZATION WITH 2000 TO 2500
J/KG OF MLCAPE WILL ONCE AGAIN SUPPORT THE THREAT FOR DAMAGING WING
GUSTS AND HAIL. ADDITIONALLY WITH THE UPPER FLOW NOW PARALLEL TO THE
WEAK SURFACE BOUNDARY...EASTERN AREAS WE WILL HAVE TO BE ON THE
ALERT FOR FOR TRAINING OF STORMS AND THE INHERENT HEAVY RAIN AND
FLOODING THREAT.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 300 AM FRIDAY...
AN UNUSUALLY AMPLIFIED UPPER LEVEL PATTERN WILL PERSIST THROUGH MUCH
OF THE PERIOD AS RIDGES DOMINATE WEST OF THE ROCKIES (EXTENDING UP
INTO CANADA) AND ACROSS THE WESTERN ATLANTIC...WITH A DEEP TROUGH
SANDWICHED IN THE MIDDLE. THIS TROUGH WILL GRADUALLY RETROGRADE
THROUGH THE PERIOD...NEVERTHELESS LEAVING CENTRAL NC WITHIN A
PERSISTENT DEEP SOUTHWESTERLY FLOW. AS A RESULT...NUMEROUS
DISTURBANCES ALOFT WILL MOVE ACROSS THE AREA AND WITH MOISTURE
REMAINING HIGH (BETWEEN 1.75-2 INCHES)...UNSETTLED WEATHER WILL
CONTINUE THROUGH THE ENTIRE LONG TERM PERIOD (IF NOT LONGER)...WITH
ABOVE NORMAL CHANCES OF SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS EXPECTED EACH DAY (MOSTLY DIURNALLY DRIVEN). AS THE
UPPER LEVEL TROUGH RETROGRADES...THE RIDGE OVER THE WESTERN ATLANTIC
WILL PUSH WESTWARD...THEREFORE EVENTUALLY EXERTING SOME MORE
INFLUENCE OVER THE REGION BY THE MIDDLE/LATTER PORTION OF THE WEEK.
THIS IS WHEN WE MAY START SEEING A DECREASE IN PRECIP COVERAGE...
ESPECIALLY OVER EASTERN NC.
OTHERWISE...WITH THE INCREASED FLOW ALOFT...DECENT DEEP LAYER SHEAR
WILL PERSIST OVER THE AREA AND THEREFORE WE SHOULD SEE MORE IN THE
WAY OF ORGANIZED CONVECTION. THIS MAY RESULT IN SOME STRONG TO
SEVERE STORMS. ANOTHER SIGNIFICANT WEATHER THREAT WILL BE THE
INCREASING FLOODING RISK AS THE AREA REMAINS IN THIS EXTENDED WET
PATTERN. DAYTIME HIGHS WILL GENERALLY BE BELOW NORMAL THROUGH THE
PERIOD...WITH MOSTLY MID 80S EXPECTED. OVERNIGHT LOWS WILL MOSTLY BE
IN THE LOWER 70S.
&&
.AVIATION /18Z THURSDAY THROUGH WEDNESDAY/...
AS OF 135 PM FRIDAY...
THIS MORNING`S IFR STRATUS AFFECTING RDU/RWI/FAY HAS SHIFTED
EASTWARD AND MIXED OUT... AND VFR CONDITIONS WILL DOMINATE THIS
AFTERNOON. BUT WE REMAIN IN A WARM... HUMID... AND UNSETTLED PATTERN
OVER CENTRAL NC... WITH A HIGH PROBABILITY OF STORMS PARTICULARLY AT
RDU/RWI/FAY MID-LATE AFTERNOON THROUGH TONIGHT. LOCAL TORRENTIAL
DOWNPOURS WITH BRIEF IFR/LIFR CONDITIONS ARE POSSIBLE WITH THESE
SHOWERS AND STORMS... ALONG WITH THE POTENTIAL FOR SURFACE WIND
GUSTS OVER 40 MPH. SCATTERED STORMS ARE EXPECTED NEAR INT/GSO AFTER
19Z... SPREADING EASTWARD TOWARD RDU/RWI/FAY AFTER 21Z AND BECOMING
NUMEROUS. STORM CHANCES WILL PERSIST IN LATE EVENING AT
RDU/RWI/FAY... TAPERING TO LIGHTER AND MORE PATCHY SHOWERS LATE
TONIGHT. BASED ON THE PERSISTENCE OF THIS PATTERN... AREAS OF
IFR/LIFR STRATUS ARE POSSIBLE AFTER 07Z TONIGHT AT RDU/RWI/FAY...
BUT ONCE AGAIN THE MODELS ARE PRESENTING CONFLICTING GUIDANCE
REGARDING THIS THREAT... SO CONFIDENCE IN OCCURRENCE OF A
PREDOMINANT IFR/LIFR CIG IS LOW. ANY SUCH STRATUS WOULD LIFT BY 14Z
SATURDAY MORNING... AND VFR CONDITIONS WOULD THEN HOLD THROUGH 18Z.
LOOKING BEYOND 18Z SATURDAY... SHOWERS/STORMS AND ATTENDANT MVFR OR
IFR CONDITIONS ARE EXPECTED TO BECOME MORE NUMEROUS SATURDAY
AFTERNOON INTO THE NIGHT... SO EXPECT INCREASINGLY POTENTIAL FOR
ADVERSE AVIATION CONDITIONS... ESPECIALLY AT RDU/RWI/FAY. WITH
MINIMAL CHANGE IN THE OVERALL PATTERN OVER THE CONUS... THE RISK FOR
DAILY NUMEROUS SUB-VFR SHOWERS AND STORMS (PRIMARILY FROM MID
AFTERNOON THROUGH MIDNIGHT) AND SHALLOW EARLY-MORNING IFR STRATUS IS
EXPECTED TO PERSIST INTO THE MIDDLE OF NEXT WEEK. -GIH
&&
.EQUIPMENT...
KRAX WSR-88D WILL REMAIN DOWN OR IN DEGRADED MODE THROUGH MID
AFTERNOON TODAY. KRAX HAS BEEN IN A SEVERELY DEGRADED MODE FOR
SEVERAL DAYS... AND THE NEEDED REPAIRS WERE DEEMED TO BE CRITICAL.
THE TEAM OF TECHNICIANS ARE MAKING THESE REPAIRS AS QUICKLY AS
POSSIBLE... AND IS WORKING HARD TO RETURN THE RADAR TO NORMAL
SERVICE THIS AFTERNOON. WE APOLOGIZE FOR THE INCONVENIENCE. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...CBL
LONG TERM...KRR
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1244 PM CDT FRI JUN 28 2013
.UPDATE...
ISSUED AT 1245 PM CDT FRI JUN 28 2013
NO MAJOR CHANGES PLANNED TO THIS UPDATE. WE WILL ADD AN UPDATED
AVIATION AND HYDROLOGY DISCUSSION...OTHERWISE THE CURRENT FORECAST
IS IN GOOD SHAPE AND WILL ONLY ADD CURRENT DATA AND TRENDS.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 350 AM CDT FRI JUN 28 2013
CHALLENGES INCLUDE CLOUD COVER/PRECIPITATION CHANCES TODAY AND
THEN TEMPERATURES THROUGH THE PERIOD. GFS/NAM/ECMWF/GEM ARE IN
GOOD AGREEMENT...BUT WILL LEAN ON LATEST RAP GUIDANCE FOR NEAR TERM
FORECAST.
FOR TODAY...STRATOCUMULUS DECK ACROSS NORTH-CENTRAL MN WILL EXPAND
SOUTH AND WEST THROUGH THE DAY GIVEN CONVECTIVE TEMPERATURES IN
THE UPPER 60S TO MID 70S. WITH A 100 KT 300 HPA JET STREAK MOVING
THROUGH NORTHWEST FLOW ALOFT AND 500 TO 1000 J/KG OF MLCAPE...
SOME OF THESE THERMAL CU MAY GIVE WAY TO SCATTERED AFTERNOON
SHOWERS AND THUNDERSTORMS. REMOVED POPS ALONG AND WEST OF THE
VALLEY THIS MORNING WITH A MOSTLY SUNNY START TO THE DAY...BUT
WILL EXPAND CHANCE POPS SOUTH AND WEST WITH INCREASING CLOUD COVER
THIS AFTERNOON. BOUNDARY LAYER IS 3 TO 6 C COLDER THAN YESTERDAY...
SO EXPECT DAYTIME HIGHS IN THE 70S. WITH 20 TO 30 KTS AT 850 HPA
TO MIX TO THE SURFACE...EXPECT ANOTHER BREEZY AFTERNOON WITH WINDS
FROM 15 TO 20 MPH AND OCCASIONAL GUSTS UP TO 30 MPH.
THERMAL CU WILL DISSIPATE AFTER SUNSET...BUT EXPECT SOME THICKER
CLOUD COVER TO TAKE ITS TIME MOVING OUT OF THE REGION OVERNIGHT.
WINDS WILL SUBSIDE WITH SURFACE HIGH PRESSURE BUILDING ACROSS THE
REGION. OVERNIGHT LOWS WILL BE IN THE 50S.
MOST OF SATURDAY WILL BE DRY...BUT DID KEEP 20 POPS REGION-WIDE
THROUGH THE DAY AS OPERATIONAL MODELS PAINT SEEMINGLY RANDOM LIGHT
QPF IN ASSOCIATION WITH A WEAK SHORT-WAVE ALOFT. SURFACE TO MID-
LEVEL FORCING IS WEAK...SO EXPECT MINIMAL ACCUMULATION WITH ANY
SHOWERS THAT DO DEVELOP. ANOTHER COOLER DAY WITH HIGHS AGAIN IN
THE 70S.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 350 AM CDT FRI JUN 28 2013
SURFACE PRESSURE RIDGE WILL SLIDE SLOWLY ACROSS THE NORTHERN
PLAINS SUNDAY AND MONDAY RESULTING IN DRY...MOSTLY SUNNY
CONDITIONS. WINDS WILL BE LIGHT AND TEMPERATURES WILL BE NEAR
SEASONAL NORMALS WITH HIGHS IN THE UPPER 70S TO LOWER 80S.
A BLEND OF THE GFS/ECMWF TO BE FOLLOWED EARLY IN THE EXTENDED THEN
TRENDING TOWARD THE GFS IN DAYS 5-7. THE UPPER PATTERN AMPLIFIES
DURING THE PERIOD WITH RIDGING OVER THE WRN CONUS AND TROF OVER THE
ERN THIRD OF THE COUNTRY. THE RIDGING OUT WEST WILL RETROGRADE
SOMEWHAT WEST ALLOWING FOR PIECES OF S/WV ENERGY TO SLIDE DOWN THE
BACK SIDE OF THE TROF BY TUE/TUE NIGHT. A FRONTAL BOUNDARY ACROSS
THE REGION WILL HELP FOCUS PRECIPITATION TUE-THU WITH WED BEING THE
MOST OPTIMAL PERIOD FOR SCATTERED SHRA/TSRA. THE BOUNDARY IS
EXPECTED TO WEAKEN BY THU. TEMPERATURES WILL BE TEMPERED WITH HIGHS
IN THE UPPER 70S TO AROUND 80 THROUGH THE WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1245 PM CDT FRI JUN 28 2013
CEILINGS HAVE BEEN RISING EAST OF THE VALLEY...AND EXPECT MAINLY VFR
SCT/BKN CU THIS AFTERNOON. NORTHWEST WINDS WILL GUST UP TO 25 TO 30
KTS...ESPECIALLY VALLEY WESTWARD...BEFORE DIMINISHING TOWARDS SUNSET.
ISO/SCT THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON INTO THE EARLY
EVENING. WITH VERY LIMITED COVERAGE...KEPT MOST TERMINALS DRY. DID
INCLUDE VICINITY THUNDER FOR A PERIOD LATE THIS AFTERNOON INTO THE
EVENING AT KBJI WHERE PRECIP CHANCES APPEAR HIGHEST. WILL HAVE TO
MONITOR FOR LOWER CEILINGS LATER TONIGHT INTO THE MORNING...ESPECIALLY
TOWARDS KBJI.
&&
.HYDROLOGY...
ISSUED AT 1245 PM CDT THU JUN 27 2013
THE RED RIVER AT FARGO IS RIGHT ABOUT CREST CURRENTLY AT OR JUST
UNDER THE MAJOR STAGE OF 30 FEET. INCREASES AT LAKE TRAVERSE WILL
ACT TO SLOW THE RATE OF FALL AT SOUTHERN VALLEY POINTS. MAINLY MINOR
FLOODING WILL CONTINUE ALONG THE SOUTHERN NORTH DAKOTA AND MINNESOTA
TRIBUTARIES. FORECAST CRESTS AND RIVER TRACES REMAIN CLOSE TO THE
PREVIOUS FORECAST. OTHERWISE...RISES ARE EXPECTED TO CONTINUE OVER
THE NEXT FEW DAYS ON CENTRAL AND NORTHERN SECTIONS OF THE RED...WITH
A FEW FORECAST POINTS RISING ABOVE MINOR FLOOD STAGE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...DK
SHORT TERM...ROGERS
LONG TERM...ROGERS/FRAZIER
AVIATION...MAKOWSKI
HYDROLOGY...WJB
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
550 PM EDT FRI JUN 28 2013
.SYNOPSIS...
AN UNSEASONABLY INTENSE UPPER TROUGH WILL CARVE OUT OVER THE
EASTERN UNITED STATES FROM THE GREAT LAKES TO THE NORTHEASTERN US
THROUGH THE WEEKEND INTO EARLY NEXT WEEK. THIS WILL BRING AN
EXTENDED PERIOD OF UNSETTLED WEATHER TO THE REGION WHICH COULD
LAST INTO THE FIRST DAYS OF JULY.
&&
.NEAR TERM /UNTIL 11 PM THIS EVENING/...
DIURNALLY ENHANCED CONVECTION CONTINUES TO FIRE ACROSS MAINLY
SOUTHERN PA EARLY THIS EVENING. FFW REMAINS IN AFFECT FOR
CLEARFIELD CO...WHERE GROUND REMAINS VERY WET FROM YESTERDAY/S
DELUGE AND MODERATE RAIN FALLING AS OF 2130Z. ELSEWHERE...SVR
WATCH 386 REMAINS IN EFFECT UNTIL 00Z FOR SOUTHERN PA...WHERE SPC
MESOANALYSIS SHOWS CAPES STILL NR 1000 J/KG.
EXPECT CONVECTION TO DIMINISH MARKEDLY AFTER SUNSET WITH THREAT OF
SVR WX ENDING LAST OVR THE SE COUNTIES BASED ON LATEST RAP OUTPUT.
LIGHT WIND...PARTIAL CLEARING AND WET GROUND SHOULD RESULT IN
AREAS OF FOG LATER TONIGHT. TEMPS SHOULD BE A BIT COOLER THAN LAST
NIGHT...AS SOMEWHAT DRIER AIR WORKS INTO THE REGION. READINGS ARND
DAWN SHOULD RANGE FROM THE M50S NW MTNS...TO THE M60S ACROSS THE
LOWER SUSQ VALLEY.
&&
.SHORT TERM /11 PM THIS EVENING THROUGH 6 PM SATURDAY/...
PRECIP WATER VALUES WILL DIP BY AROUND 0.50 INCH TONIGHT...AND
PERIODS OF CLEARING WILL ALLOW TEMPS TO COOL OFF NICELY...ESPECIALLY
ACROSS CENTRAL AND NWRN PENN WHERE LOWS EARLY SAT WILL VARY FROM
THE MID 50S TO AROUND 60F. LINGERING...SLIGHTLY HIGHER PWATS ACRS
THE LOWER SUSQ VALLEY WILL KEEP TEMPS FROM FALLING BELOW THE MID
60S.
DAYTIME HIGHS CONTINUE TO TREND DOWNWARD INTO THE WEEKEND WITH HIGH
TEMPS A FEW...TO SEVERAL DEG BELOW NORMAL ACROSS THE CENTRAL AND NW
MTNS GIVEN CLOUDIER SKIES AND AFTERNOON PRECIPITATION.
THE UNSEASONABLY LOW HEIGHTS WILL COVER THE OHIO VALLEY AND
WESTERN PA ON SATURDAY...A PATTERN FAVORABLE FOR DIURNAL CONVECTION
GIVEN COOL TEMPS ALOFT/STEEP LAPSE RTS. WILL MAINTAIN LIKELY POPS
FOR PM SHRA/TSRA ACROSS THE WESTERN COUNTIES BASED ON LATEST 00Z/03Z
GEFS AND SREF GUIDANCE. ENS MEAN 925MB TEMPS INDICATE SAT WILL BE
ANOTHER WARM DAY ACROSS THE EASTERN HALF OF THE STATE...WHILE
CLOUDS/PRECIP KEEP READINGS COOLER ACROSS THE WEST.
&&
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
THE SLOW MOVING UPPER TROUGH THAT IS EXPECTED TO DEVELOP AND
LINGER OVER THE EASTERN US IS FORCING ONE OF THOSE RARE FORECASTS
FROM THE DEPARTMENT OF REDUNDANCY DEPARTMENT.
DAILY MENTION OF SHOWERS AND STORMS WILL SOUND TEDIOUS AND
REPETITIVE IN THE FORECAST...BUT THERE ISN`T A PERIOD THROUGH
THE WHOLE OF NEXT WEEK WHEN THERE SEEMS LIKE THE REGION WILL NOT
SEE AT LEAST SCATTERED SHOWERS OR STORMS.
TEMPERATURES WILL AVERAGE NEAR TO SLIGHTLY BELOW NORMAL GIVEN THE
EXPECTED LOWER THAN NORMAL UPPER HEIGHTS...CLOUD COVER AND
EXPECTED PRECIPITATION CHANCES.
THE ANOMALOUS UPPER TROUGH IS EXPECTED TO SLOWLY RETROGRADE NEXT
WEEK...WITH HINTS THAT THE THE BERMUDA RIDGE WILL EXPERIENCE A
RESURGENCE INTO THE EASTERN US TOWARD NEXT WEEKEND...HINTING AT A
WARMER BUT STILL STILL HUMID AIRMASS TO RETURN TO THE REGION.
&&
.AVIATION /22Z FRIDAY THROUGH WEDNESDAY/...
BANDS OF SHOWERS AND STORMS WILL CONTINUE INTO THE MID EVENING
HOURS...IF NOT LONGER. TEMPS ALOFT COOLER THAN YESTERDAY...AND
STORMS HIGHER...THUS MORE OF A HAIL THREAT TODAY. ALSO A WIND
THREAT...AS WAS THE CASE YESTERDAY.
LATER TONIGHT...EXPECT FOG TO BECOME THE MAIN CONCERN.
NOT MUCH CHANGE EXPECTED INTO EARLY NEXT WEEK...AS A LARGE
UPPER LEVEL TROUGH WILL REMAIN OVER THE EASTERN U.S. INTO THE
WEEKEND...BEFORE MIGRATING SLOWLY WESTWARD INTO THE MIDWEST AND
PLAINS DURING THE FIRST WEEK OF JULY. THIS WILL RESULT IN A
PROLONGED PERIOD OF UNSETTLED CONDITIONS WITH DAILY CHANCES FOR
SCT SHOWERS AND THUNDERSTORMS. FOG WILL ALSO BE LIKELY A FEW
HOURS EITHER SIDE OF SUNRISE.
OUTLOOK...
SUN-WED...VFR-MVFR WITH SCT SHOWERS AND TSTMS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DEVOIR/LA CORTE/STEINBUGL
NEAR TERM...DEVOIR/FITZGERALD
SHORT TERM...LAMBERT
LONG TERM...LA CORTE/LAMBERT
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS AMARILLO TX
554 PM CDT FRI JUN 28 2013
.AVIATION...
VFR CONDITIONS TO PREVAIL THROUGH THIS TAF ISSUANCE. NORTHWEST UPPER
LEVEL FLOW WILL KEEP THE RISK OF CONVECTION IN AND AROUND THE
TERMINAL BOTH THIS EVENING AND TOMORROW AFTERNOON. CONVECTIVE CHANCES
AT THE TERMINALS THIS EVENING REMAIN TOO LOW TO INSERT INTO
PREVAILING GROUPS AND WILL BE DEPENDENT ON CONVECTION OVER NEW MEXICO
PERSISTING INTO THE PANHANDLES. WILL CONTINUE TO CLOSELY MONITOR THE
CONVECTIVE TRENDS AND WILL MAKE UPDATES AS NEEDED. TOMORROWS CHANCES
LOOK HIGHER THAN TODAYS BUT ARE AT THE VERY END OF THIS TAF ISSUANCE.
&&
.PREV DISCUSSION... /ISSUED 348 PM CDT FRI JUN 28 2013/
SHORT TERM...
AFTERNOON WV SATELLITE IMAGERY AND RUC UPPER AIR ANALYSIS SHOWS THE
LARGE UPPER RIDGE SQUARELY CENTERED OVER THE FOUR CORNERS REGION.
WHILE THIS RIDGE WILL LIKELY BRING RECORD HEAT TO THE WESTERN
CONUS...THE PLACEMENT OF THIS RIDGE MEANS THE PANHANDLES WILL SEE A
SHIFT TOWARD WETTER AND COOLER WX CONDITIONS. MEANWHILE THE COLD
FRONT THAT PUSHED THROUGH THE AREA LAST NIGHT HAS SLID INTO SOUTHERN
TX. EASTERLY TO SOUTHEASTERLY UPSLOPE FLOW RESULTED IN COOLER
CONDITIONS ALTHOUGH ITS STILL TOASTY WITH TEMPS THIS AFTERNOON
CLIMBING WELL INTO THE 90S. CONVECTION HAS STARTED TO DEVELOP OVER
THE HIGHER TERRAIN IN NM AND CO WHICH IS TYPICAL IN THIS TYPE OF WX
PATTERN. HOWEVER GIVEN THAT THE UPPER FLOW IS MORE NORTH-
NORTHEASTERLY STORMS WILL HAVE A TOUGH TIME MAKING IT INTO THE
WESTERN TX PANHANDLES. ALTHOUGH INSTABILITY IS IN PLACE ACROSS THE
AREA /PER SPC MESOSCALE ANALYSIS SHOWING AROUND 1000-1500 J/KG SBCAPE
VALUES/ BULK SHEAR IS WEAK SO IF ANY STORMS DO MAKE IT INTO THE
NORTHWESTERN ZONES THEY WILL NOT BE ORGANIZED. HOWEVER PRECIP CHANCES
IMPROVE SAT AS AN UPPER TROUGH OVER THE GREAT LAKES REGION
RETROGRADES INTO THE MIDWEST WHILE THE WESTERN CONUS RIDGE EDGES A
BIT FURTHER TO THE WEST. EXPECT THE UPPER FLOW TO TRANSITION MORE TO
THE NORTHWEST WHICH WOULD FAVOR A GREATER COVERAGE OF STORMS. STORMS
MAY BE MORE ORGANIZED AS WELL OWING TO LARGER VALUES OF CAPE AND
SHEAR. ALTHOUGH SPC HAS KEPT THE AREA OUT OF A SLIGHT RISK FOR SEVERE
STORMS LIKELY DUE TO A LACK OF ANY APPRECIABLE CONVECTIVE INITIATION
MECHANISM...LARGE HAIL AND DAMAGING WIND GUSTS WILL BE THE MAIN
THREATS.
LONG TERM...
THE UPPER TROUGH CONTINUES TO RETROGRADE TOWARD THE OH VALLEY EARLY
NEXT WEEK WHILE THE UPPER RIDGE REMAINS OVER THE WESTERN CONUS. THE
PANHANDLES WILL REMAIN UNDER STOUT NORTHERLY UPPER FLOW ALTHOUGH AT
TIMES...ESPECIALLY EARLY ON IN THE WEEK...PRECIP CHANCES MAY BE
LIMITED DUE TO A MORE NORTHERLY COMPONENT ALOFT. BY WEDNESDAY AND
ESPECIALLY INDEPENDENCE DAY...PRECIP CHANCES LOOK BETTER AS THE UPPER
TROUGH MOVES INTO THE CENTRAL PLAINS WHILE THE UPPER FLOW BACKS
TOWARD THE NORTHWEST. THIS PATTERN LOOKS LIKE IT WILL HOLD TOWARD THE
END OF THE WEEK. GIVEN MEDIUM RANGE MODELS HAVE NOT DIVERGED TOO MUCH
FROM THEIR SOLUTIONS HAVE OPTED TO NOT MAKE TOO MANY CHANGES FOR THIS
PERIOD. BESIDES THE INCREASED RAIN CHANCES...TEMPS WILL CONTINUE TO
COOL WITH HIGHS MAINLY IN THE 80S EXPECTED AREA WIDE. THIS WILL BE A
NICE CONTRAST TO THE HOT WEEK WE`VE HAD.
CLK
FIRE WEATHER...
NEITHER ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED
OVER THE NEXT SEVERAL DAYS DUE TO MINIMUM RELATIVE HUMIDITY
VALUES ABOVE 20 PERCENT...PERIODIC CHANCES FOR SHOWERS AND
THUNDERSTORMS...AND 20 FOOT WINDS GENERALLY STAYING UNDER 15 MPH.
CLK
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
14/02
AREA FORECAST DISCUSSION
NWS AMARILLO TX
348 PM CDT FRI JUN 28 2013
.SHORT TERM...
AFTERNOON WV SATELLITE IMAGERY AND RUC UPPER AIR ANALYSIS SHOWS THE
LARGE UPPER RIDGE SQUARELY CENTERED OVER THE FOUR CORNERS REGION.
WHILE THIS RIDGE WILL LIKELY BRING RECORD HEAT TO THE WESTERN
CONUS...THE PLACEMENT OF THIS RIDGE MEANS THE PANHANDLES WILL SEE A
SHIFT TOWARD WETTER AND COOLER WX CONDITIONS. MEANWHILE THE COLD
FRONT THAT PUSHED THROUGH THE AREA LAST NIGHT HAS SLID INTO SOUTHERN
TX. EASTERLY TO SOUTHEASTERLY UPSLOPE FLOW RESULTED IN COOLER
CONDITIONS ALTHOUGH ITS STILL TOASTY WITH TEMPS THIS AFTERNOON
CLIMBING WELL INTO THE 90S. CONVECTION HAS STARTED TO DEVELOP OVER
THE HIGHER TERRAIN IN NM AND CO WHICH IS TYPICAL IN THIS TYPE OF WX
PATTERN. HOWEVER GIVEN THAT THE UPPER FLOW IS MORE NORTH-
NORTHEASTERLY STORMS WILL HAVE A TOUGH TIME MAKING IT INTO THE
WESTERN TX PANHANDLES. ALTHOUGH INSTABILITY IS IN PLACE ACROSS THE
AREA /PER SPC MESOSCALE ANALYSIS SHOWING AROUND 1000-1500 J/KG SBCAPE
VALUES/ BULK SHEAR IS WEAK SO IF ANY STORMS DO MAKE IT INTO THE
NORTHWESTERN ZONES THEY WILL NOT BE ORGANIZED. HOWEVER PRECIP CHANCES
IMPROVE SAT AS AN UPPER TROUGH OVER THE GREAT LAKES REGION
RETROGRADES INTO THE MIDWEST WHILE THE WESTERN CONUS RIDGE EDGES A
BIT FURTHER TO THE WEST. EXPECT THE UPPER FLOW TO TRANSITION MORE TO
THE NORTHWEST WHICH WOULD FAVOR A GREATER COVERAGE OF STORMS. STORMS
MAY BE MORE ORGANIZED AS WELL OWING TO LARGER VALUES OF CAPE AND
SHEAR. ALTHOUGH SPC HAS KEPT THE AREA OUT OF A SLIGHT RISK FOR SEVERE
STORMS LIKELY DUE TO A LACK OF ANY APPRECIABLE CONVECTIVE INITIATION
MECHANISM...LARGE HAIL AND DAMAGING WIND GUSTS WILL BE THE MAIN
THREATS.
.LONG TERM...
THE UPPER TROUGH CONTINUES TO RETROGRADE TOWARD THE OH VALLEY EARLY
NEXT WEEK WHILE THE UPPER RIDGE REMAINS OVER THE WESTERN CONUS. THE
PANHANDLES WILL REMAIN UNDER STOUT NORTHERLY UPPER FLOW ALTHOUGH AT
TIMES...ESPECIALLY EARLY ON IN THE WEEK...PRECIP CHANCES MAY BE
LIMITED DUE TO A MORE NORTHERLY COMPONENT ALOFT. BY WEDNESDAY AND
ESPECIALLY INDEPENDENCE DAY...PRECIP CHANCES LOOK BETTER AS THE UPPER
TROUGH MOVES INTO THE CENTRAL PLAINS WHILE THE UPPER FLOW BACKS
TOWARD THE NORTHWEST. THIS PATTERN LOOKS LIKE IT WILL HOLD TOWARD THE
END OF THE WEEK. GIVEN MEDIUM RANGE MODELS HAVE NOT DIVERGED TOO MUCH
FROM THEIR SOLUTIONS HAVE OPTED TO NOT MAKE TOO MANY CHANGES FOR THIS
PERIOD. BESIDES THE INCREASED RAIN CHANCES...TEMPS WILL CONTINUE TO
COOL WITH HIGHS MAINLY IN THE 80S EXPECTED AREA WIDE. THIS WILL BE A
NICE CONTRAST TO THE HOT WEEK WE`VE HAD.
CLK
&&
.FIRE WEATHER...
NEITHER ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED
OVER THE NEXT SEVERAL DAYS DUE TO MINIMUM RELATIVE HUMIDITY
VALUES ABOVE 20 PERCENT...PERIODIC CHANCES FOR SHOWERS AND
THUNDERSTORMS...AND 20 FOOT WINDS GENERALLY STAYING UNDER 15 MPH.
CLK
&&
.PRELIMINARY POINT TEMPS/POPS...
AMARILLO TX 67 90 62 85 60 / 10 10 30 20 20
BEAVER OK 66 92 61 85 57 / 10 10 20 10 10
BOISE CITY OK 65 91 61 83 59 / 20 10 30 20 30
BORGER TX 70 94 66 88 64 / 10 10 30 10 20
BOYS RANCH TX 68 96 66 87 63 / 10 10 30 20 30
CANYON TX 65 91 62 85 59 / 10 10 30 20 20
CLARENDON TX 69 93 64 86 61 / 10 10 30 10 20
DALHART TX 64 92 62 84 61 / 20 10 30 20 30
GUYMON OK 65 92 62 86 59 / 20 10 30 10 20
HEREFORD TX 63 93 63 84 58 / 10 10 30 20 30
LIPSCOMB TX 66 92 61 85 59 / 10 10 20 10 10
PAMPA TX 66 90 62 83 59 / 10 10 30 10 20
SHAMROCK TX 68 94 64 85 60 / 10 10 30 10 10
WELLINGTON TX 69 97 65 89 61 / 10 10 30 10 10
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
07/05
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
539 PM EDT FRI JUN 28 2013
.SYNOPSIS...
AN UPPER LEVEL TROUGH WILL RESIDE OVER THE EASTERN UNITED STATES
THIS WEEKEND. THIS PATTERN WILL RESULT IN A DAILY THREAT OF
SHOWERS AND THUNDERSTORMS...WITH SOME POTENTIAL FOR SEVERE STORMS
DURING THE AFTERNOONS AND EVENINGS.
&&
.NEAR TERM /THROUGH SATURDAY/...
AS OF 530 PM EDT FRIDAY...
HAVE KEPT THE SVR THUNDERSTORM WATCH 388 CONTINUING ALTHOUGH SVR
THREAT LOOKS TO BE DIMINISHING AS LINE OF STORMS EXITS THE CWA.
STILL MESOANALYSIS INDICATES INSTABILITY AND SHEAR SUCH THAT SOME
REDEVELOPMENT INTO THE NEXT HOUR OR IS POSSIBLE...PER CHAT WITH
SPC. MAY BE ABLE TO CANCEL IT EARLY THOUGH. THE WESTERLY FLOW
HOWEVER IS ACTING TO SUPPRESS ANY DEVELOPMENT WEST OF THE PIEDMONT
AS CU HAS BEEN MORE OF FAIR WX VARIETY.
LOWERED POPS CONSIDERABLY ACROSS THE BOARD WITH HIGHER POPS IN THE
SOUTHEAST. THE 18Z NAM/12Z LOCAL WRF AND 20Z HRRR HANDLING THIS
SETUP WELL AND GOING INTO THE EVENING LOOKS LIKE FOCUS FOR MORE
SHOWERS WILL BE INTO THE NC MTNS/FOOTHILLS AND ACROSS SE WV
PORTIONS OF SW VA...ALTHOUGH INSTABILITY SHOULD BE LOWER AND
THREAT OF STORMS LOOKS SMALL. MADE CHANGES TO SKY COVER TO ALLOW
FOR MORE SUNSHINE THROUGH 7 PM...OUTSIDE OF CONVECTION AREA.
PREVIOUS VALID DISCUSSION...
VIRTUALLY ALL ACTIVITY SHOULD SUBSIDE BY MIDNIGHT. LOWS WERE ONLY
DROPPED A DEGREE OR TWO AS DEWPOINTS SHOULD FALL SLIGHTLY
OVERNIGHT...BUT CONCERNS ABOUT DEBRIS CLOUD COVER WILL HOLD OFF
DECENT RADIATIONAL COOLING.
BY SATURDAY...THE UPPER LEVEL TROUGH WILL BE DIGGING SOUTHWARD
OVER THE OHIO RIVER VALLEY. THE WESTERLY FLOW DOES NOT APPEAR TO
BE AS STRONG COMPARED TO FRIDAY...AND THE WIND SHEAR PROFILE IS
CONSIDERABLY LESS IMPRESSIVE ACCORDING TO ALL MODEL SOUNDINGS.
THUS...THE ATMOSPHERIC ENVIRONMENT SUGGESTS LESS ORGANIZED
CONVECTION AND MORE PULSE SHOWERS AND THUNDERSTORMS TO POP UP
DURING EARLY SATURDAY AFTERNOON. THE MORE ORGANIZED CONVECTION
APPEARS TO BE WELL EAST OF THE CWA ACCORDING TO THE SYNOPTIC
MODELS. WHILE THE DRIER BOUNDARY LAYER COULD DELAY THE ONSET OF
ACTIVITY...THE PRESENCE OF THE UPPER LEVEL TROUGH AND HIGHS
REACHING THE UPPER 70S TO THE UPPER 80S SUGGEST THERE IS STILL A
POTENTIAL SEVERE THREAT...PARTICULARLY EAST OF THE BLUE RIDGE.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
AS OF 400 PM EDT FRIDAY...
AMPLIFIED/BLOCKY PATTERN IN PLACE WITH A TROUGH OVER MUCH OF THE
EASTERN CONUS. DISTURBANCES WILL CONTINUE TO ARRIVE FROM THE WEST
AND NORTHWEST THROUGH THE WEEKEND...LEADING TO IN AND OUT SHOWERS
AND THUNDERSTORMS THROUGH THE WEEKEND. SUNDAY SHOULD BE THE
WETTEST DAY AS AN UPPER LOW POTENTIALLY CUTS OFF AND RECENTERS
OVER THE LOWER OHIO VALLEY AS THE TROUGH STRENGTHENS....AND
SURFACE WINDS BACK. MORE SOUTHERLY COMPONENT WILL HELP FOCUS
STORMS ALONG THE BLUE RIDGE. WATER PROBLEMS MAY EVENTUALLY DEVELOP
WITH SEVERAL DAYS OF THIS PATTERN. WITH MORE CLOUDS AND STORMS
THIS WEEKEND...ALSO WITH SLIGHT COOLING AT H85/H7...TEMPS SHOULD
BE A SLIGHT COOLING TREND...ALTHOUGH STILL WARM AND HUMID THROUGH
THE WEEKEND.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 400 PM EDT FRIDAY...
UPPER AIR PATTERN REMAINS WITH SOME RETROGRESSION OF THE BERMUDA
HIGH NEXT WEEKEND...PERHAPS FINALLY LEADING TO A DRIER SOLUTION.
BEFORE THEN...THE ONLY CHANGE TO THE PATTERN INTO THE MIDDLE OF NEXT
WEEK WILL BE THE CLOSING OFF OF AN UPPER RIDGE JUST NW OF BERMUDA.
THIS WILL ALLOW SHRTWAVES/JET STREAKS TO TAKE ALMOST A SOUTH TO
NORTH PATH OVER OUR REGION...WHICH WILL LEAD TO EVEN MORE WIDESPREAD
SHOWERS AND THUNDERSTORMS INTO NEXT WEEK.
&&
.AVIATION /22Z FRIDAY THROUGH WEDNESDAY/...
AS OF 150 PM EDT FRIDAY...
VFR CONDITIONS WITH GUSTY WESTERLY WINDS WILL PREVAIL THROUGH THIS
AFTERNOON. IN ADDITION...SHOWERS AND THUNDERSTORMS WILL POP UP
DURING THE NEXT FEW HOURS. WITH SCATTERED CONVECTIVE ACTIVITY
LIKELY THROUGHOUT THE AREA...VCTS WAS KEPT AT ALL TAF SITES.
THE SHOWERS AND THUNDERSTORM SHOULD SUBSIDE BY SUNSET...AND WINDS
WILL ALSO DECREASE. THE MODEL GUIDANCE IS NOT REALLY PESSIMISTIC
ABOUT FOG AND STRATUS TONIGHT...SO ONLY A PERIOD OF MVFR FOG WAS
MENTIONED AT BLF/LWB/BCB...BUT ROA/LYH/DAN WAS LEFT AT VFR.
WINDS WILL NOT BE AS GUSTY DURING SATURDAY. HOWEVER...THE DAILY
THREAT FOR AFTERNOON TO EVENING SHOWERS AND THUNDERSTORMS WILL
CONTINUE THROUGH THE WEEKEND INTO EARLY NEXT WEEK COURTESY OF AN
UPPER LEVEL TROUGH OVER THE OHIO RIVER VALLEY. VFR CONDITIONS
SHOULD BE PRESENT DURING THE MORNINGS...WITH SOME POTENTIAL FOR
MVFR IN THE SHOWERS AND THUNDERSTORMS...AND MAYBE A LITTLE FOG OR
STRATUS IN SHELTERED AREAS OVERNIGHT. BY THE MIDDLE OF NEXT
WEEK...THE UPPER LEVEL TROUGH WILL SHIFT WESTWARD...AS A STRONG
UPPER LEVEL RIDGE BUILDS OVER THE EAST COAST. THUS...THE COVERAGE
IN DIURNAL CONVECTIVE ACTIVITY MAY GRADUALLY WANE WITH TIME.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...PW
NEAR TERM...PW/WP
SHORT TERM...KM
LONG TERM...KM
AVIATION...PW
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1100 AM PDT Fri Jun 28 2013
.SYNOPSIS...
Temperatures across the Inland Northwest will warm over the
weekend and reach very hot temperatures early next week. There
will be a small chance of strong thunderstorms Saturday over the
Idaho Panhandle. Temperatures Monday through Wednesday will be
some of the hottest we have seen in several years. Many places
will experience triple digit heat early next week.
&&
.DISCUSSION...
A very minor forecast update sent out mainly to put in clear skies
across much of the region except for over the Cascades and across
the northern mountains. The rest of the forecast remains on track.
latest 12Z model guidance still supports developing thunderstorms
over the Cascades, mainly near the crest. We will start out with a
little bit of a cap across these areas, but the higher peaks are
expected to break through. Once (if) the cap is broken, there is a
convective potential of up to around 700 J/KG to be tapped into
and strong shear of around 40 to 50 kts between 0-6 km. These
parameters would support the possibility for storms going severe.
The problem with seeing any severe thunderstorms today, is that
the only kicker in town to provide additional synoptic lift is
still too far offshore to have any effect on thunderstorms today.
This means that the only lift we will generate will be from
thermodynamics of the atmosphere (aka buoyancy relationships). It
may take much of this afternoon before storms can get going as
well with only a few hours of really good buoyancy during our peak
heating. The NAM appears to be overdoing our dew point temps over
the mountains, so the GFS is being relied upon much more for
convective potential. Although we will see a considerable amount
of CAPE over the Northeast Blue Mountains into the Central
Panhandle Mountains today, there also looks to be a stronger cap
in place of around 50-100 J/KG; thus, we will continue to go with
clear skies across these areas. The SREF supports thunderstorms only
over the Cascade Mountains this afternoon as well. The HRRR model
would suggest no thunderstorms across the region today, so there is
some uncertainty when consulting some of the high resolution short
term model guidance. /SVH
&&
.AVIATION...
18Z TAFS: A strong ridge building in from the south will promote
mostly clear skies across much of the region into this evening. Some
developing cumulus is expected over the northern WA Cascade Mtns and
across the northern mtns of NE WA and N ID near the Canadian border.
Cumulus over the northern WA Cascades may be able to break the
capping inversion this afternoon for isolated thunderstorms across
the higher peaks near the crest, but any storms that do develop are
not expected to impact the KEAT taf site. The focus for tonight will
be for the potential for some elevated thunderstorms pushing into
the region from the south. There is still some uncertainty with the
coverage thunderstorms, but all taf sites could be impacted.
Thunderstorm threat for KLWS, KPUW, KMWH and KEAT is expected to
hold off until about 09Z and then for KGEG, KSFF and KCOE a few
hours later after 12Z. /SVH
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 87 63 89 65 90 68 / 0 10 20 20 10 0
Coeur d`Alene 87 60 89 62 89 65 / 0 10 20 20 10 0
Pullman 89 59 88 61 89 65 / 0 20 20 20 10 10
Lewiston 95 67 95 69 97 69 / 0 20 20 20 10 10
Colville 88 57 92 60 93 63 / 10 10 20 20 10 0
Sandpoint 83 53 89 58 88 59 / 0 0 20 20 10 0
Kellogg 85 60 88 62 87 64 / 10 10 20 30 10 0
Moses Lake 92 65 93 66 97 68 / 0 20 20 10 0 0
Wenatchee 91 68 92 68 96 71 / 0 10 20 10 0 0
Omak 89 62 91 63 96 66 / 0 10 20 10 0 0
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
946 AM PDT Fri Jun 28 2013
.SYNOPSIS...
Temperatures across the Inland Northwest will warm over the
weekend and reach very hot temperatures early next week. There
will be a small chance of strong thunderstorms Saturday over the
Idaho Panhandle. Temperatures Monday through Wednesday will be
some of the hottest we have seen in several years. Many places
will experience triple digit heat early next week.
&&
.DISCUSSION...
A very minor forecast update sent out mainly to put in clear skies
across much of the region except for over the Cascades and across
the northern mountains. The rest of the forecast remains on track.
latest 12Z model guidance still supports developing thunderstorms
over the Cascades, mainly near the crest. We will start out with a
little bit of a cap across these areas, but the higher peaks are
expected to break through. Once (if) the cap is broken, there is a
convective potential of up to around 700 J/KG to be tapped into
and strong shear of around 40 to 50 kts between 0-6 km. These
parameters would support the possibility for storms going severe.
The problem with seeing any severe thunderstorms today, is that
the only kicker in town to provide additional synoptic lift is
still too far offshore to have any effect on thunderstorms today.
This means that the only lift we will generate will be from
thermodynamics of the atmosphere (aka buoyancy relationships). It
may take much of this afternoon before storms can get going as
well with only a few hours of really good buoyancy during our peak
heating. The NAM appears to be overdoing our dew point temps over
the mountains, so the GFS is being relied upon much more for
convective potential. Although we will see a considerable amount
of CAPE over the Northeast Blue Mountains into the Central
Panhandle Mountains today, there also looks to be a stronger cap
in place of around 50-100 J/KG; thus, we will continue to go with
clear skies across these areas. The SREF supports thunderstorms
only over the Cascade Mountains this afternoon as well. The HRRR model
would suggest no thunderstorms across the region today, so there
is some uncertainty when consulting some of the high resolution
short term model guidance. /SVH
&&
.AVIATION...
12Z TAFS: A strong ridge building in from the south will keep dry
conditions over the area today. There is a possibility for isolated
thunderstorms over the North WA Cascades btwn 20z-03z but this
should not impact KEAT. An increase in mid level
moisture/instability arrives after 06z Saturday with elevated
thunderstorms possibility developing around KMWH/KPUW/KLWS. For
KGEG/KSFF/KCOE the best chances for thunderstorms will hold off til
after 12z Sat. JW
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 87 63 89 65 90 68 / 0 10 20 20 10 0
Coeur d`Alene 87 60 89 62 89 65 / 0 10 20 20 10 0
Pullman 89 59 88 61 89 65 / 0 20 20 20 10 10
Lewiston 95 67 95 69 97 69 / 0 20 20 20 10 10
Colville 88 57 92 60 93 63 / 10 10 20 20 10 0
Sandpoint 83 53 89 58 88 59 / 0 0 20 20 10 0
Kellogg 85 60 88 62 87 64 / 10 10 20 30 10 0
Moses Lake 92 65 93 66 97 68 / 0 20 20 10 0 0
Wenatchee 91 68 92 68 96 71 / 0 10 20 10 0 0
Omak 89 62 91 63 96 66 / 0 10 20 10 0 0
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
218 PM CDT FRI JUN 28 2013
.SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)
ISSUED AT 218 PM CDT FRI JUN 28 2013
WATER VAPOR IMAGERY/RAP 500MB ANALYSIS SHOWS A CLOSED LOW NEAR THE
LAKE HURON/EERIE REGION WITH A TROUGH EXTENDING WESTWARD ACROSS
LOWER MI INTO NORTHERN WI/MN. RAP ANALYZING SEVERAL EMBEDDED
POSITIVE VORTICITY MAXIMA WITHIN THIS TROUGH...ADVECTING SOUTHWARD
ACROSS THE AREA. THIS TROUGH/VORTICITY...COMBINED WITH FAIRLY STEEP LOWER
LEVEL LAPSE RATES WAS PRODUCING SCATTERED SHOWER ACTIVITY MAINLY
EAST OF THE MISSISSIPPI RIVER. OTHERWISE...AN EXTENSIVE CUMULUS
FIELD WAS NOTED ACROSS THE REGION UNDER THE COOLER CYCLONIC FLOW
ALOFT WITH SURFACE TEMPERATURES RANGING FROM THE 65-70 DEGREES
ACROSS NORTHERN WI...TO THE NEAR 80 ACROSS NORTHEAST IA/FAR
SOUTHWEST WI. IN ADDITION...BREEZY NORTHWEST WINDS MAKING IT FEEL
LIKE MORE OF AN EARLY AUTUMN DAY ACROSS THE REGION.
LOOK FOR THE MID-LEVEL TROUGH TO CONTINUE DROPPING SOUTHWARD ACROSS
THE AREA TONIGHT...PRODUCING EXTENSIVE CLOUD COVER AND SCATTERED
SHOWER ACTIVITY. LOWS OVERNIGHT EXPECTED TO DROP OFF INTO THE UPPER
50S TO THE LOWER 60S.
COOLER CYCLONIC FLOW TO CONTINUE ACROSS THE AREA ON SATURDAY.
THUS...ANOTHER DAY OF ABUNDANT CLOUD COVER AND SCATTERED SHOWERS CAN
BE EXPECTED. AN ISOLATED RUMBLE OF THUNDER MAY ALSO OCCUR AS 0-1KM
ML MUCAPE PERKS UP INTO THE 400-1000J/KG RANGE BY AFTERNOON. BAY
LATER IN THE AFTERNOON...EXPECTING MOST OF THE CONVECTION TO BE
CONFINED SOUTH MAINLY SOUTH OF I-94 AS THE MID-LEVEL TROUGH AXIS
DROPS FARTHER SOUTH INTO IA/IL AND RIDGING STARTS TO BUILD ACROSS
THE NORTH. OTHERWISE...PLAN ON TEMPERATURES TO BE A COUPLE DEGREES
COOLER THAN FRIDAY...TOPPING OFF IN THE 70-75 RANGE.
THE MID-LEVEL TROUGH WILL CONTINUE TO ROTATE SOUTH OF THE AREA
SATURDAY NIGHT WITH HIGH PRESSURE BUILDING IN FROM THE NORTHERN
PLAINS/MN. AS A RESULT...LOOK FOR A RAPID DIMINISHING OF SHOWER
ACTIVITY ACROSS SOUTHERN PORTIONS OF THE FORECAST AREA WITH CLEARING
SKIES FROM NORTH TO SOUTH AS THE EVENING PROGRESSES. MOSTLY CLEAR
SKIES WILL THEN BE NOTED OVERNIGHT WITH TEMPERATURES COOLING INTO
THE UPPER 40S TO THE MIDDLE 50S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 218 PM CDT FRI JUN 28 2013
PATTERN REMAINS BASICALLY UNCHANGED FROM SUNDAY THROUGH TUESDAY
NIGHT WITH THE MID-LEVEL TROUGH AXIS EXTENDING FROM THE GREAT LAKES
TO TO THE OHIO RIVER VALLEY WHILE RIDGE OF HIGH PRESSURE CONTROLS
THE NORTHERN PLAINS INTO THE UPPER MISSISSIPPI RIVER REGIONS. THIS
KEEPS THE AREA DRY WITH TEMPERATURES REMAINING A FEW DEGREES BELOW
NORMAL. PLAN ON HIGHS IN THE MID/UPPER 70S WITH OVERNIGHT LOWS IN
THE 50S. IT APPEARS THE GFS/ECMWF EVENTUALLY SHOW THE MID-LEVEL
TROUGH FILLING/LIFTING NORTHEAST INTO THE EASTERN GREAT
LAKES/EASTERN ONTARIO BY FRIDAY WITH FLOW BECOMING MORE LAMINAR/HIGH
ZONAL ACROSS CANADA. SO...LOOKS LIKE A SLIGHT CHANCE OF SHOWERS AND
ISOLATED THUNDERSTORMS WEDNESDAY AND THURSDAY WITH FRIDAY DRY AND
BECOMING WARMER. PLAN ON HIGHS IN THE UPPER 70S ON WEDNESDAY...
WARMING INTO THE 80-85 DEGREE RANGE BY FRIDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED
AT 1206 PM CDT FRI JUN 28 2013
SCATTERED SHOWERS HAVE DEVELOPED THIS MORNING...MAINLY ACROSS
WISCONSIN. THESE SHOWERS HAVE DROPPED THE VISIBILITY BRIEFLY INTO
THE MVFR RANGE. AS THESE MOVE SOUTH...APPEARS THEY HAVE THE BEST
POTENTIAL TO IMPACT KLSE...SO HAVE INCLUDED A TEMPO GROUP FOR THE
EARLY AFTERNOON TO SHOW THE POSSIBILITY OF THE SHOWERS GOING OVER
THE AIRFIELD WITH A REDUCTION TO THE VISIBILITY. ONCE THE INITIAL
WAVE OF SHOWERS GOES BY...CONFIDENCE ON HOW THE REMAINDER OF THE
AFTERNOON AND EVENING WILL TURN OUT BECOMES PRETTY LOW. THE 28.15Z
RAP SHOWS THE CYCLONIC FLOW ALOFT WILL CONTINUE INTO TONIGHT WHICH
WILL HELP TO MAINTAIN THE CLOUDS OVER THE AREA. SHOULD BE
ADDITIONAL SHORT WAVE TROUGHS IN THIS FLOW...BUT THEY WILL PRODUCE
VERY LITTLE PVA ADVECTION AND THUS NOT SURE HOW MANY ADDITIONAL
SHOWERS WILL BE AROUND. THE RAP...28.14Z ARX LAPS AND 28.12Z NAM
ALL TRY TO SHOW ANOTHER ROUND OF SHOWERS COMING OFF LAKE SUPERIOR
OVERNIGHT AND MAINLY IMPACTING MINNESOTA AND IOWA AS THEY COME
SOUTH. WILL MAINTAIN THE MENTION OF VCSH THROUGH THE NIGHT TO
ACCOUNT FOR THIS AND LET LATER FORECASTS DETAIL THIS THREAT BETTER
IF THESE SHOWERS DO DEVELOP. ALSO SOME POTENTIAL FOR MVFR CEILINGS
AS THESE ARE CURRENTLY OVER NORTHERN WISCONSIN. THESE HAVE BEEN
MOVING SOUTH AND HAVE INCLUDED THEM FROM THE EARLY EVENING THROUGH
THE OVERNIGHT. WILL HAVE TO MONITOR THE SOUTHWARD PROGRESS AND
UPDATE IF THEY LOOK TO MOVE IN SOONER.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM....DAS
AVIATION...04