Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/20/12
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1036 PM MDT SUN JUN 17 2012
.AVIATION...
VFR CONDITIONS ARE EXPECTED AT ALL 3 TAF SITES...KCOS...KPUB AND
KALS DURING THE NEXT 24H. IT WILL BE VERY HOT TOMORROW WITH 100+
READINGS AT KPUB...95-97F AT KCOS AND 85-89 AT KALS. SOME GUSTS TO
25 MPH FROM A S-SW TO SW DIRECTION WILL BE POSSIBLE TOMORROW
AFTERNOON AT ALL TAF SITES.
&&
.PREV DISCUSSION... /ISSUED 513 PM MDT SUN JUN 17 2012/
UPDATE...
UPDATED THE FCST TO MENTION SMOKE IN THE FCST. MODELS SHOWS LOWER
LVL FLOW FROM THE WNW THE REST OF TODAY SHIFTING TO THE WEST
TONIGHT AND EVENTUALLY W-SW TOMORROW. SMOKE WILL SETTLE TONIGHT
ONCE THE INVERSION SETS IN...ESPECIALLY OVER TELLER COUNTY.
WE CAN SMELL THE SMOKE HERE AT THE WX OFFICE WHICH IS LOCATED AT
THE PUEBLO AIRPORT. /34
PREV DISCUSSION... /ISSUED 312 PM MDT SUN JUN 17 2012/
SHORT TERM...
(TONIGHT AND MONDAY)
THE MAIN CONCERN IS FIRE WEATHER ISSUES. THE FLOW ALOFT TODAY IS
WEST TO NW AND THE MTN AND HIGH VALLEY AREAS HAVE BEEN SEEING WIND
GUSTS THAT ARE MEETING CRITERIA FOR THE RED FLAG WARNING...AS ARE
THE RH VALUES. ON MONDAY THE FLOW ALOFT BECOMES WEST TO SOUTHWEST
AS AN UPR TROF MOVING INTO WRN MT...AND IT LOOKS LIKE WIND GUSTS
OVER THE MTS AND HIGH VALLEYS WILL AGAIN REACH RED FLAG
CRITERIA...AS WILL THE MIN RH VALUES. THUS WL UPGRADE THE FIRE
WEATHER WATCH THAT IS CURRENTLY IN EFFECT FOR THE MTS AND HIGH
VALLEYS...TO A RED FLAG WARNING.
THE NSSL 4KM WRF AND HRRR CONTINUE TO SHOW THE POTENTIAL FOR A
LITTLE CONVECTION NR THE SRN BORDER THRU ABOUT 00Z. HAVE
SEE A FEW ECHOES IN THE OK PANHANDLE...BUT WL KEEP POPS LESS THAN 15
PERCENT ALONG THE SRN BORDER FOR THE VERY EARLY EVENING HOURS.
OTHERWISE THE WEATHER WILL BE DRY ACRS THE FORECAST AREA TONIGHT.
MONDAY WILL BE ANOTHER HOT AND DRY DAY. H7 TEMPS IN THE AFTERNOON
ARE EXPECTED TO RANGE FROM 17C-21C. TEMPS ACRS THE SERN PLAINS WILL
BE IN THE UPPER 90S TO AROUND 103...WHILE THE HIGH VALLEYS SHOULD
SEE MID AND UPR 80S. THE RECORD HIGH FOR COLO SPGS MON IS 96...FOR
PUEBLO IS 104 AND FOR ALAMOSA IS 90. /28
LONG TERM...
(MONDAY NIGHT THROUGH SUNDAY)
.CONTINUED HOT AND DRY...
EXTENDED FORECAST CONTINUES TO LOOK FAIRLY UNEVENTFUL...A TYPICAL
PRE-MONSOONAL SUMMERTIME PATTERN FOR THE ROCKIES. TUE SHOULD BE THE
LAST DAY OF POTENTIAL RECORD-BREAKING HEAT...AS H7 TEMPS REMAIN IN
THE 18-20 DEG C RANGE. FIRE WX DANGER WILL BE ELEVATED ON TUE...BUT
THERE IS STILL SOME QUESTION AS TO HOW STRONG SURFACE WINDS WILL BE
ON TUE...AND THAT WILL DETERMINE RED FLAG STATUS. THE NAM 12KM
SUGGESTS A FAIRLY BROAD LEE TROUGH WILL DEVELOP OVR THE AREA...AND
THE STRONGEST SFC GRADIENT WILL BE OVER W KS AND THE OK PANHANDLE.
THIS COULD KEEP WINDS FAIRLY LIGHT E OF THE MTS. HOWEVER...THERE IS A
STRONG JET TO OUR N...AND WITH DEEP MIXING EXPECT SOME STRONGER
GUSTS ESPECIALLY OVR WRN AND NRN PORTIONS OF THE CWA. WINDS SHOULD
STILL BE LIGHTER THAN ON MON...HOWEVER. WILL HOLD OFF ON ANY FIRE WX
HEADLINES FOR NOW.
FRONT SHOULD ARRIVE EARLY WED...AND TEMPS WILL FALL BACK
DRAMATICALLY ON WED AS H7 TEMPS FALL BACK BELOW 10 DEG C. COULD EVEN
SEE SOME UPPR 70S ON WED OVR THE PLAINS...FOR A PLEASANT REPRISE
FROM THE HEAT. THE PLEASANTRY WILL BE SHORT-LIVED...HOWEVER...AS A
TROUGH RELOADS ON THE W COAST FOR THE LATTER PART OF THE WEEK...AND
DRY AND HOT W-SW FLOW RESUMES. TEMPS COULD EASILY BE BACK INTO THE
UPPR 90S TO NEAR 100 BY THE END OF THE WEEK. VERY LITTLE IF ANY
PRECIP IS EXPECTED AS WELL. FORTUNATELY...THE GENERALLY LIGHT SFC
WINDS WILL LIMIT CRITICAL FIRE DANGER. THERE IS ALSO SOME INDICATION
THAT MID LEVEL MOISTURE WILL BEGIN MOVING NWD INTO THE S CENTRAL
ROCKIES FOR THE WEEKEND...BUT AT THIS POINT THE MOISTURE TAP LOOKS
MODEST AT BEST. DOG DAYS OF SUMMER APPEAR TO BE WITH US UNTIL FURTHER
NOTICE. 44
AVIATION...
VFR CONDITIONS WILL BE SEEN AT KCOS...KPUB AND KALS FOR THE NEXT 24
HRS. WIND GUSTS OF 15-25 KTS CAN BE EXPECTED AT KALS THRU ABOUT
01Z. KPUB AND KCOS WILL PROBABLY SEE GUSTS UP TO AROUND 20 KTS THRU
ABOUT 01Z. WINDS WILL PICK UP AGAIN ON MONDAY AFTERNOON WITH GUSTS
OF 15-25 KTS FROM THE SOUTH TO SOUTHWEST AT THE TAF SITES.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 11 AM TO 9 PM MDT MONDAY FOR COZ064-
220>225.
&&
$$
34/34
AREA FORECAST DISCUSSION
NWS NEW YORK NY
941 PM EDT TUE JUN 19 2012
.SYNOPSIS...
HIGH PRESSURE WILL BUILD SOUTHEAST OF THE REGION...PROVIDING HOT
AND HUMID CONDITIONS TO THE TRI-STATE AREA THROUGH THURSDAY. A COLD
FRONT WILL APPROACH THURSDAY NIGHT AND MOVE SLOWLY THROUGH FRIDAY
AFTERNOON INTO FRIDAY NIGHT. WEAK HIGH PRESSURE FOLLOWS FOR THE
WEEKEND. A STRONG FRONTAL SYSTEM MAY AFFECT THE REGION MONDAY INTO
TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
WEAK WARM FRONT AT THE SFC MOVES THROUGH AS RIDGE BUILDS ALOFT.
MCS OVER GREAT LAKES REGION HAS WEAKENED. THERE IS SOME
INDICATION FROM MESOSCALE MODELS FOR A FEW SHOWERS APPROACHING
FROM THE NORTHWEST LATE TONIGHT. HOWEVER...NOW FEEL ANY SHOWER
COVERAGE WILL BE TOO LOW TO INCLUDE FOR THE OVERNIGHT FORECAST.
THIS WILL NEED TO BE WATCHED THOUGH...BUT SUBSIDENCE MAY PREVAIL.
PATCHY FOG POSSIBLE AFTER MIDNIGHT DUE TO HIGH RH AND LIGHT
ONSHORE FLOW. TEMPS WILL MOVE LITTLE OVERNIGHT...60S TO LOWER 70S
IN THE NYC METRO.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
HOT AND HUMID CONDITIONS EXPECTED ON WEDNESDAY AND WEDNESDAY NIGHT.
STRONG UPPER RIDGING BUILDS TO THE WEST AND SFC RIDGING SETS UP OFF
THE CAROLINA COAST. THIS WILL RESULT IN DEEP LAYER WESTERLY FLOW
INLAND...A SET UP FAVORABLE FOR HIGH TEMPERATURES ACROSS THE
INTERIOR. A WEST TO SOUTHWEST FLOW WILL SET UP CLOSER TO THE COAST.
MODELS IN GOOD AGREEMENT WITH H8 TEMPERATURES RISING TO 20-21 C
DEGREES WITH GOOD MIXING TO AROUND THE SAME HEIGHT.
WITH STRONG SUBSIDENCE AND PLENTY OF SUNSHINE...WIDESPREAD TEMPS IN
THE MID TO UPPER 90S EXPECTED ACROSS THE NYC/NJ METRO AND INTERIOR.
TEMPERATURES ALONG THE COAST WILL BE SLIGHTLY COOLER WITH THE
DEVELOPMENT OF AN AFTERNOON SEABREEZE. THIS SHOULD LIMIT
TEMPERATURES TO THE UPPER 80S AND LOWER 90S ALONG SOUTHERN AND
EASTERN COASTAL AREAS.
DEWPOINTS ARE EXPECTED TO CLIMB INTO THE MID AND UPPER 60S. THIS
WILL RESULT IN HEAT INDEX VALUES IN THE UPPER 90S AND LOWER 100S FOR
RANGE FOR THE INTERIOR NYC METRO...NE NJ...LOWER HUDSON
VALLEY...NORTHERN NASSAU COUNTY...AND INTERIOR SW CT. AS A
RESULT...A HEAT ADVISORY WILL BE ISSUED.
TEMPERATURES WILL REMAIN QUITE WARM WEDNESDAY NIGHT WITH LOWS ONLY
FALLING INTO THE UPPER 60S AND 70S. TEMPERATURES IN NYC MAY REMAIN
IN THE UPPER 70S TO NEAR 80S.
THERE IS A MODERATE RISK OF RIP CURRENTS ON WEDNESDAY.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
MAIN STORY CONTINUES TO BE HIGH HEAT AND HUMIDITY ON THU...GRADUALLY
RELENTING FRIDAY INTO SATURDAY.
STRONG UPPER RIDGING SLIDES TO THE EAST COAST ON THURSDAY WITH
SURFACE RIDGING SLOWLY SLIDING EAST OF THE SE US COAST. MODELS
CONTINUE IN GOOD AGREEMENT WITH 850 HPA TEMPS AROUND 20-21Z AND
MIXING TO AROUND THAT HEIGHT. WITH STRONG SUBSIDENCE AND PLENTY OF
SUNSHINE...WIDESPREAD TEMPS IN THE MID TO UPPER 90S EXPECTED
ACROSS THE NYC/NJ METRO AND INTERIOR ON THURSDAY. IN FACT...A FEW
SPOTS MAY TOUCH 100 ACROSS URBAN NE NJ AND INTERIOR NYC. AFTERNOON
THERMAL TROUGHING WILL LIKELY RESULT IN AFTERNOON SEABREEZE
DEVELOPMENT ALONG THE COAST...LIMITING TEMPS TO THE LOWER TO MID
90S ALONG SOUTH AND EASTERN SHORE COASTAL AREAS. WITH DOWNSLOPE
FLOW AND MODELS INDICATING 850 HPA DEWPOINTS A BIT LOWER ON
THURSDAY...LEANING TOWARDS DEWPOINTS IN THE MID TO UPPER 60S ON
THURSDAY DURING MAX HEATING. THIS WILL SPELL HEAT INDICES IN THE
100 TO 104 RANGE FOR THE NYC METRO...NE NJ...LOWER HUDSON
VALLEY...NORTHERN NASSAU...AND INTERIOR SW CONN ONCE AGAIN. SO
WILL ISSUE HEAT ADVISORY FOR THESE AREAS INTO THURSDAY. THE HEAT
ADVISORY MAY NEED TO BE EXPANDED FURTHER EAST DEPENDING ON DEWPOINT
MIX OUT. LOWS THU NIGHT SHOULD REMAIN OPPRESSIVE...GENERALLY IN THE
70S ACROSS MUCH OF THE REGION...AROUND 80 NYC/NJ METRO.
IN TERMS OF CONVECTION...ONLY AN ISOLATED TSTM THREAT LATE
THURSDAY ACROSS FAR NW ORANGE AS UPPER RIDGE SLIDES FAR ENOUGH
EAST TO ALLOW WEAK VORT ENERGY TO WORK OVER THE REGION. ANY
CONVECTION SHOULD BE LIMITED TO DIFFERENTIAL HEATING OFF
POCONOS/CATSKILLS WHEN MID-LEVEL CAPPING BEGINS TO WEAKEN...THEN
SINKING SE.
BROAD UPPER TROUGH SLIDES TOWARDS THE REGION FROM THE GREAT LAKES
THURSDAY NIGHT INTO FRIDAY...WITH SURFACE COLD FRONT SLOWLY
SLIDING OVER THE REGION. MODELS INDICATING A WEAK LEAD VORT AXIS
THURSDAY NIGHT...WHICH MAY ALLOW FOR ISOLATED CONVECTION IN THE
VICINITY OF THE COLD FRONT...MAINLY WESTERN SECTIONS.
FOR FRIDAY...SCATTERED SHRA/TSTM DEVELOPMENT POSSIBLE ON WITH
DAYTIME INSTABILITY...SHORTWAVE ENERGY APPROACHING...AND COLD
FRONT SLOWLY SLIDING THROUGH. A FEW STRONG TO SEVERE STORMS ARE
POSSIBLE ALONG AND EAST OF THE COLD FRONT WITH AT LEAST MODERATE
INSTABILITY AND INCREASING SHEAR...IF CAPPING WEAKENS ENOUGH TO
ALLOW FOR INITIATION. WITH MAIN SHORTWAVE FORCING LAGGING DOES NOT
LOOKS LIKE A WIDESPREAD STRONG TO SEVERE CONVECTION SETUP. WITH
INITIALLY VERY WARM AIRMASS...HIGHS WELL INTO THE 80S TO LOWER 90S
LOOK VERY POSSIBLE AREAWIDE ON FRIDAY DESPITE PARTIAL SUNSHINE.
MODELS IN DECENT AGREEMENT WITH THE COLD FRONT ONLY SLOWLY SLIDING
EAST OF THE AREA BY SATURDAY MORNING AS THE SHORTWAVE AXIS
APPROACHES...SO THREAT FOR SHRA/TSTMS MAY LINGER ACROSS FAR EASTERN
SECTIONS WELL INTO FRIDAY NIGHT.
SHORTWAVE AXIS SLIDES EAST THROUGH THE REGION ON SATURDAY.
INSTABILITY CU AND A LINGERING SHOWER OR TSTM POSSIBLE ACROSS FAR
EASTERN SECTIONS SATURDAY AFTERNOON...BUT CONFIDENCE ON THIS IS
LOW SO HAVE LEFT DRY.
OTHERWISE MEAN TROUGHING EXPECTED INTO EARLY NEXT WEEK...WITH
MODELS COMING INTO GOOD AGREEMENT WITH ANOMALOUSLY STRONG UPPER
LOW SWINGING FROM THE GREAT LAKES INTO THE NORTHEAST FOR MONDAY
INTO TUESDAY. AS A RESULT CONFIDENCE IS INCREASING ON AN UNUSUALLY
STRONG FRONTAL SYSTEM/SURFACE LOW AFFECTING THE REGION MONDAY INTO
TUESDAY.
&&
.AVIATION /02Z WEDNESDAY THROUGH SUNDAY/...
WARM FRONT OVER EASTERN PA/WESTERN NJ WILL TRACK ACROSS THE
TERMINALS TONIGHT. HIGH PRES BUILDS SOUTHWEST OF THE AREA ON
WEDNESDAY.
SOUTHERLY FLOW CONTINUES THIS EVENING AT 10-15 KT NEAR THE COAST
AND 5-10 KT INLAND. WINDS BECOME VRB02-05KT THIS EVENING...BUT
WITH PASSAGE OF WARM FRONT...KNYC TERMINALS WILL BECOME SW AT 5-7
KT.
MAIN FORECAST PROBLEM TONIGHT WILL BE THE POTENTIAL FOR
FOG/STRATUS TO DEVELOP. WITH PASSAGE OF WARM FRONT SOMETIME IN THE
04-06Z TIME FRAME...PREVAILING SOUTHWEST FLOW USHERS A WARM AND
HUMID AIRMASS INTO THE REGION. WITH SFC TEMPS FALLING AND DEW
POINT TEMPS RISING...WIDESPREAD FOG MAY DEVELOP. 18Z MAV GUIDANCE
AND 22Z LAV GUIDANCE INDICATE WIDESPREAD VLIFR CONDS LATE TONIGHT
THROUGH WEDNESDAY MORNING. WILL HOLD OFF ON GOING THAT LOW WITH
00Z TAF PACKAGE...AS CONFIDENCE IS LOW IN THAT OCCURRING. BUT
WILL INTRODUCE A TEMPO GROUP FOR IFR CONDS FOR THE TERMINALS.
IN ADDITION...MCS OVER THE GREAT LAKES PASSES NORTH OF THE
TERMINALS TONIGHT. HOWEVER...THE HRRR MODEL IS INDICATING THAT MCS
COULD TURN RIGHT AND DROP SOUTH TOWARDS THE LOCAL TERMINALS.
CONFIDENCE IS LOW IN THAT OCCURRING AS WELL...AND WITH THE PUBLIC
FORECAST ONLY INDICATING SLIGHT CHANCE POPS...WILL GO AHEAD AND
LEAVE OUT OF THE TAFS AS WELL.
CONDS IMPROVE WEDNESDAY MORNING BETWEEN 12-14Z. VFR ON TAP WITH A
WEST TO SOUTHWEST FLOW AT 8-12 KT. SEA BREEZES POSSIBLE AT COASTAL
TERMINALS IN THE AFTERNOON WHICH WOULD TURN WINDS TO MORE OF A
SOUTHERLY FLOW. SLANT RANGE VSBY MAY BE REDUCED IN HAZE AT KEWR ON
WEDNESDAY.
AN ISOLATED AIRMASS TSTM IS POSSIBLE IN THE AFTERNOON.
...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)
KJFK FCSTER COMMENTS: LOW CONFIDENCE ON DEVELOPMENT OF
FOG/STRATUS. AMENDMENTS LIKELY DEPENDING ON ITS DEVELOPMENT THIS
EVENING.
KLGA FCSTER COMMENTS: LOW CONFIDENCE ON DEVELOPMENT OF
FOG/STRATUS. AMENDMENTS LIKELY DEPENDING ON ITS DEVELOPMENT THIS
EVENING.
KEWR FCSTER COMMENTS: LOW CONFIDENCE ON DEVELOPMENT OF
FOG/STRATUS. AMENDMENTS LIKELY DEPENDING ON ITS DEVELOPMENT THIS
EVENING.
KTEB FCSTER COMMENTS: LOW CONFIDENCE ON DEVELOPMENT OF
FOG/STRATUS. AMENDMENTS LIKELY DEPENDING ON ITS DEVELOPMENT THIS
EVENING.
KHPN FCSTER COMMENTS: LOW CONFIDENCE ON DEVELOPMENT OF
FOG/STRATUS. AMENDMENTS LIKELY DEPENDING ON ITS DEVELOPMENT THIS
EVENING.
KISP FCSTER COMMENTS: LOW CONFIDENCE ON DEVELOPMENT OF
FOG/STRATUS.
.OUTLOOK FOR 00Z THURSDAY THROUGH SUNDAY...
.WED NIGHT...SUB-VFR CONDS POSSIBLE IN FOG.
.THU...VFR. AN ISOLD AIRMASS TSTM POSSIBLE IN THE AFTN/EVE.
.FRI...MVFR OR LOWER IN SCT/NMRS TSTMS...ESPECIALLY IN THE AFTN AND
EVE.
.SAT...MVFR IN MRNG CONVECTIVE DEBRIS. AFTN VFR.
.SUN...VFR.
&&
.MARINE...
WINDS AND SEAS WILL REMAIN BELOW SCA LEVELS THROUGH THE WEEKEND.
COMBINED SEAS FROM SW FLOW INCREASING TO AROUND 15 KT...AND
INCOMING E-SE SWELL FROM AN OFFSHORE LOW...COULD BUILD OCEAN SEAS
UP TO 4 FT AT TIMES THROUGH THE END OF THE WEEK...WITH ROUGH
CONDITIONS AT THE INLETS.
WINDS WILL DIMINISH ON FRIDAY...AND THEN SHIFT MORE TO THE WEST
TO NORTHWEST BEHIND A COLD FRONTAL PASSAGE FRIDAY NIGHT. A WEAK
PRESSURE GRADIENT WILL BE ACROSS THE WATERS SATURDAY AND SUNDAY WITH
HIGH PRESSURE GRADUALLY BUILDING IN FROM THE WEST.
&&
.HYDROLOGY...
LOCALIZED HEAVY DOWNPOURS EXPECTED WITH ANY CONVECTION ON
FRIDAY...AS PWATS INCREASE TO AROUND 2 INCHES...PRESENTING AN
ISOLATED FLASH FLOOD THREAT.
&&
.CLIMATE...
TEMPERATURES FOR JUNE 20...
..LOCATION.........FORECAST HIGH......RECORD HIGH.......YEAR....
CENTRAL PARK NY.........96................98............1923....
LAGUARDIA NY............97................96............1953....
KENNEDY NY..............89................93............1995....
NEWARK NJ...............98................97............1953....
ISLIP NY................89................93............1995....
BRIDGEPORT CT...........90................93............1953....
TEMPERATURES FOR JUNE 21...
..LOCATION.........FORECAST HIGH......RECORD HIGH.......YEAR....
CENTRAL PARK NY.........97................97.........1953/1988..
LAGUARDIA NY............99................97............1953....
KENNEDY NY..............95................95............1988....
NEWARK NJ..............100................100...........1953....
ISLIP NY................95................93............1988....
BRIDGEPORT CT...........93................95............1953....
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...HEAT ADVISORY FROM NOON WEDNESDAY TO 8 PM EDT THURSDAY FOR
CTZ005-006-009.
NY...HEAT ADVISORY FROM NOON WEDNESDAY TO 8 PM EDT THURSDAY FOR
NYZ067>075-176>178.
NJ...HEAT ADVISORY FROM NOON WEDNESDAY TO 8 PM EDT THURSDAY FOR
NJZ002-004-006-103>108.
MARINE...NONE.
&&
$$
SYNOPSIS...BC/NV
NEAR TERM...BC/PW
SHORT TERM...BC
LONG TERM...NV
AVIATION...MPS/12
MARINE...BC/NV
HYDROLOGY...BC/NV
CLIMATE...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
756 PM EDT TUE JUN 19 2012
.SYNOPSIS...
HIGH PRESSURE WILL BUILD SOUTHEAST OF THE REGION...PROVIDING HOT
AND HUMID CONDITIONS TO THE TRI-STATE AREA THROUGH THURSDAY. A COLD
FRONT WILL APPROACH THURSDAY NIGHT AND MOVE SLOWLY THROUGH FRIDAY
AFTERNOON INTO FRIDAY NIGHT. WEAK HIGH PRESSURE FOLLOWS FOR THE
WEEKEND. A STRONG FRONTAL SYSTEM MAY AFFECT THE REGION MONDAY INTO
TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
WEAK WARM FRONT MOVES THROUGH AS RIDGE BUILDS ALOFT.
MCS OVER GREAT LAKES REGION...AND GLOBAL MODELS DID NOT HANDLE
THIS WELL. THIS ACTIVITY WILL WEAKEN OVERNIGHT AS IT MOVES SE OVER
RIDGE...BUT SOME INDICATION FROM MESOSCALE MODELS FOR WEAK
ACTIVITY FOR PORTIONS OF THE CWA LATE TONIGHT. ADDED SLIGHT CHANCE
DUE TO PRESENCE OF ELEVATED INSTABILITY...WEAK VORTICITY
ADVECTION.
ADDED PATCHY FOG TO GRIDS...BUT UNCERTAINTY REMAINS. HOWEVER...DPS
COULD INCREASE SLIGHTLY...RESULTING IN A SMALL T/TD SPREAD LATE
TONIGHT.
OVERNIGHT LOWS WILL ONLY FALL INTO THE 60S...WITH LOWER 70S IN
THE NYC METRO.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
HOT AND HUMID CONDITIONS EXPECTED ON WEDNESDAY AND WEDNESDAY NIGHT.
STRONG UPPER RIDGING BUILDS TO THE WEST AND SFC RIDGING SETS UP OFF
THE CAROLINA COAST. THIS WILL RESULT IN DEEP LAYER WESTERLY FLOW
INLAND...A SET UP FAVORABLE FOR HIGH TEMPERATURES ACROSS THE
INTERIOR. A WEST TO SOUTHWEST FLOW WILL SET UP CLOSER TO THE COAST.
MODELS IN GOOD AGREEMENT WITH H8 TEMPERATURES RISING TO 20-21 C
DEGREES WITH GOOD MIXING TO AROUND THE SAME HEIGHT.
WITH STRONG SUBSIDENCE AND PLENTY OF SUNSHINE...WIDESPREAD TEMPS IN
THE MID TO UPPER 90S EXPECTED ACROSS THE NYC/NJ METRO AND INTERIOR.
TEMPERATURES ALONG THE COAST WILL BE SLIGHTLY COOLER WITH THE
DEVELOPMENT OF AN AFTERNOON SEABREEZE. THIS SHOULD LIMIT
TEMPERATURES TO THE UPPER 80S AND LOWER 90S ALONG SOUTHERN AND
EASTERN COASTAL AREAS.
DEWPOINTS ARE EXPECTED TO CLIMB INTO THE MID AND UPPER 60S. THIS
WILL RESULT IN HEAT INDEX VALUES IN THE UPPER 90S AND LOWER 100S FOR
RANGE FOR THE INTERIOR NYC METRO...NE NJ...LOWER HUDSON
VALLEY...NORTHERN NASSAU COUNTY...AND INTERIOR SW CT. AS A
RESULT...A HEAT ADVISORY WILL BE ISSUED.
TEMPERATURES WILL REMAIN QUITE WARM WEDNESDAY NIGHT WITH LOWS ONLY
FALLING INTO THE UPPER 60S AND 70S. TEMPERATURES IN NYC MAY REMAIN
IN THE UPPER 70S TO NEAR 80S.
THERE IS A MODERATE RISK OF RIP CURRENTS ON WEDNESDAY.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
MAIN STORY CONTINUES TO BE HIGH HEAT AND HUMIDITY ON THU...GRADUALLY
RELENTING FRIDAY INTO SATURDAY.
STRONG UPPER RIDGING SLIDES TO THE EAST COAST ON THURSDAY WITH
SURFACE RIDGING SLOWLY SLIDING EAST OF THE SE US COAST. MODELS
CONTINUE IN GOOD AGREEMENT WITH 850 HPA TEMPS AROUND 20-21Z AND
MIXING TO AROUND THAT HEIGHT. WITH STRONG SUBSIDENCE AND PLENTY OF
SUNSHINE...WIDESPREAD TEMPS IN THE MID TO UPPER 90S EXPECTED
ACROSS THE NYC/NJ METRO AND INTERIOR ON THURSDAY. IN FACT...A FEW
SPOTS MAY TOUCH 100 ACROSS URBAN NE NJ AND INTERIOR NYC. AFTERNOON
THERMAL TROUGHING WILL LIKELY RESULT IN AFTERNOON SEABREEZE
DEVELOPMENT ALONG THE COAST...LIMITING TEMPS TO THE LOWER TO MID
90S ALONG SOUTH AND EASTERN SHORE COASTAL AREAS. WITH DOWNSLOPE
FLOW AND MODELS INDICATING 850 HPA DEWPOINTS A BIT LOWER ON
THURSDAY...LEANING TOWARDS DEWPOINTS IN THE MID TO UPPER 60S ON
THURSDAY DURING MAX HEATING. THIS WILL SPELL HEAT INDICES IN THE
100 TO 104 RANGE FOR THE NYC METRO...NE NJ...LOWER HUDSON
VALLEY...NORTHERN NASSAU...AND INTERIOR SW CONN ONCE AGAIN. SO
WILL ISSUE HEAT ADVISORY FOR THESE AREAS INTO THURSDAY. THE HEAT
ADVISORY MAY NEED TO BE EXPANDED FURTHER EAST DEPENDING ON DEWPOINT
MIX OUT. LOWS THU NIGHT SHOULD REMAIN OPPRESSIVE...GENERALLY IN THE
70S ACROSS MUCH OF THE REGION...AROUND 80 NYC/NJ METRO.
IN TERMS OF CONVECTION...ONLY AN ISOLATED TSTM THREAT LATE
THURSDAY ACROSS FAR NW ORANGE AS UPPER RIDGE SLIDES FAR ENOUGH
EAST TO ALLOW WEAK VORT ENERGY TO WORK OVER THE REGION. ANY
CONVECTION SHOULD BE LIMITED TO DIFFERENTIAL HEATING OFF
POCONOS/CATSKILLS WHEN MID-LEVEL CAPPING BEGINS TO WEAKEN...THEN
SINKING SE.
BROAD UPPER TROUGH SLIDES TOWARDS THE REGION FROM THE GREAT LAKES
THURSDAY NIGHT INTO FRIDAY...WITH SURFACE COLD FRONT SLOWLY
SLIDING OVER THE REGION. MODELS INDICATING A WEAK LEAD VORT AXIS
THURSDAY NIGHT...WHICH MAY ALLOW FOR ISOLATED CONVECTION IN THE
VICINITY OF THE COLD FRONT...MAINLY WESTERN SECTIONS.
FOR FRIDAY...SCATTERED SHRA/TSTM DEVELOPMENT POSSIBLE ON WITH
DAYTIME INSTABILITY...SHORTWAVE ENERGY APPROACHING...AND COLD
FRONT SLOWLY SLIDING THROUGH. A FEW STRONG TO SEVERE STORMS ARE
POSSIBLE ALONG AND EAST OF THE COLD FRONT WITH AT LEAST MODERATE
INSTABILITY AND INCREASING SHEAR...IF CAPPING WEAKENS ENOUGH TO
ALLOW FOR INITIATION. WITH MAIN SHORTWAVE FORCING LAGGING DOES NOT
LOOKS LIKE A WIDESPREAD STRONG TO SEVERE CONVECTION SETUP. WITH
INITIALLY VERY WARM AIRMASS...HIGHS WELL INTO THE 80S TO LOWER 90S
LOOK VERY POSSIBLE AREAWIDE ON FRIDAY DESPITE PARTIAL SUNSHINE.
MODELS IN DECENT AGREEMENT WITH THE COLD FRONT ONLY SLOWLY SLIDING
EAST OF THE AREA BY SATURDAY MORNING AS THE SHORTWAVE AXIS
APPROACHES...SO THREAT FOR SHRA/TSTMS MAY LINGER ACROSS FAR EASTERN
SECTIONS WELL INTO FRIDAY NIGHT.
SHORTWAVE AXIS SLIDES EAST THROUGH THE REGION ON SATURDAY.
INSTABILITY CU AND A LINGERING SHOWER OR TSTM POSSIBLE ACROSS FAR
EASTERN SECTIONS SATURDAY AFTERNOON...BUT CONFIDENCE ON THIS IS
LOW SO HAVE LEFT DRY.
OTHERWISE MEAN TROUGHING EXPECTED INTO EARLY NEXT WEEK...WITH
MODELS COMING INTO GOOD AGREEMENT WITH ANOMALOUSLY STRONG UPPER
LOW SWINGING FROM THE GREAT LAKES INTO THE NORTHEAST FOR MONDAY
INTO TUESDAY. AS A RESULT CONFIDENCE IS INCREASING ON AN UNUSUALLY
STRONG FRONTAL SYSTEM/SURFACE LOW AFFECTING THE REGION MONDAY INTO
TUESDAY.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
WARM FRONT OVER EASTERN PA/WESTERN NJ WILL TRACK ACROSS THE
TERMINALS TONIGHT. HIGH PRES BUILDS SOUTHWEST OF THE AREA ON
WEDNESDAY.
SOUTHERLY FLOW CONTINUES THIS EVENING AT 10-15 KT NEAR THE COAST
AND 5-10 KT INLAND. WINDS BECOME VRB02-05KT THIS EVENING...BUT
WITH PASSAGE OF WARM FRONT...KNYC TERMINALS WILL BECOME SW AT 5-7
KT.
MAIN FORECAST PROBLEM TONIGHT WILL BE THE POTENTIAL FOR
FOG/STRATUS TO DEVELOP. WITH PASSAGE OF WARM FRONT SOMETIME IN THE
04-06Z TIME FRAME...PREVAILING SOUTHWEST FLOW USHERS A WARM AND
HUMID AIRMASS INTO THE REGION. WITH SFC TEMPS FALLING AND DEW
POINT TEMPS RISING...WIDESPREAD FOG MAY DEVELOP. 18Z MAV GUIDANCE
AND 22Z LAV GUIDANCE INDICATE WIDESPREAD VLIFR CONDS LATE TONIGHT
THROUGH WEDNESDAY MORNING. WILL HOLD OFF ON GOING THAT LOW WITH
00Z TAF PACKAGE...AS CONFIDENCE IS LOW IN THAT OCCURRING. BUT
WILL INTRODUCE A TEMPO GROUP FOR IFR CONDS FOR THE TERMINALS.
IN ADDITION...MCS OVER THE GREAT LAKES PASSES NORTH OF THE
TERMINALS TONIGHT. HOWEVER...THE HRRR MODEL IS INDICATING THAT MCS
COULD TURN RIGHT AND DROP SOUTH TOWARDS THE LOCAL TERMINALS.
CONFIDENCE IS LOW IN THAT OCCURRING AS WELL...AND WITH THE PUBLIC
FORECAST ONLY INDICATING SLIGHT CHANCE POPS...WILL GO AHEAD AND
LEAVE OUT OF THE TAFS AS WELL.
CONDS IMPROVE WEDNESDAY MORNING BETWEEN 12-14Z. VFR ON TAP WITH A
WEST TO SOUTHWEST FLOW AT 8-12 KT. SEA BREEZES POSSIBLE AT COASTAL
TERMINALS IN THE AFTERNOON WHICH WOULD TURN WINDS TO MORE OF A
SOUTHERLY FLOW. SLANT RANGE VSBY MAY BE REDUCED IN HAZE AT KEWR ON
WEDNESDAY.
AN ISOLATED AIRMASS TSTM IS POSSIBLE IN THE AFTERNOON.
...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)
KJFK FCSTER COMMENTS: LOW CONFIDENCE ON DEVELOPMENT OF
FOG/STRATUS. AMENDMENTS LIKELY DEPENDING ON ITS DEVELOPMENT THIS
EVENING.
KLGA FCSTER COMMENTS: LOW CONFIDENCE ON DEVELOPMENT OF
FOG/STRATUS. AMENDMENTS LIKELY DEPENDING ON ITS DEVELOPMENT THIS
EVENING.
KEWR FCSTER COMMENTS: LOW CONFIDENCE ON DEVELOPMENT OF
FOG/STRATUS. AMENDMENTS LIKELY DEPENDING ON ITS DEVELOPMENT THIS
EVENING.
KTEB FCSTER COMMENTS: LOW CONFIDENCE ON DEVELOPMENT OF
FOG/STRATUS. AMENDMENTS LIKELY DEPENDING ON ITS DEVELOPMENT THIS
EVENING.
KHPN FCSTER COMMENTS: LOW CONFIDENCE ON DEVELOPMENT OF
FOG/STRATUS. AMENDMENTS LIKELY DEPENDING ON ITS DEVELOPMENT THIS
EVENING.
KISP FCSTER COMMENTS: LOW CONFIDENCE ON DEVELOPMENT OF
FOG/STRATUS.
.OUTLOOK FOR 00Z THURSDAY THROUGH SUNDAY...
.WED NIGHT...SUB-VFR CONDS POSSIBLE IN FOG.
.THU...VFR. AN ISOLD AIRMASS TSTM POSSIBLE IN THE AFTN/EVE.
.FRI...MVFR OR LOWER IN SCT/NMRS TSTMS...ESPECIALLY IN THE AFTN AND
EVE.
.SAT...MVFR IN MRNG CONVECTIVE DEBRIS. AFTN VFR.
.SUN...VFR.
&&
.MARINE...
WINDS AND SEAS WILL REMAIN BELOW SCA LEVELS THROUGH THE WEEKEND.
COMBINED SEAS FROM SW FLOW INCREASING TO AROUND 15 KT...AND
INCOMING E-SE SWELL FROM AN OFFSHORE LOW...COULD BUILD OCEAN SEAS
UP TO 4 FT AT TIMES THROUGH THE END OF THE WEEK...WITH ROUGH
CONDITIONS AT THE INLETS.
WINDS WILL DIMINISH ON FRIDAY...AND THEN SHIFT MORE TO THE WEST
TO NORTHWEST BEHIND A COLD FRONTAL PASSAGE FRIDAY NIGHT. A WEAK
PRESSURE GRADIENT WILL BE ACROSS THE WATERS SATURDAY AND SUNDAY WITH
HIGH PRESSURE GRADUALLY BUILDING IN FROM THE WEST.
&&
.HYDROLOGY...
LOCALIZED HEAVY DOWNPOURS EXPECTED WITH ANY CONVECTION ON
FRIDAY...AS PWATS INCREASE TO AROUND 2 INCHES...PRESENTING AN
ISOLATED FLASH FLOOD THREAT.
&&
.CLIMATE...
TEMPERATURES FOR JUNE 20...
..LOCATION.........FORECAST HIGH......RECORD HIGH.......YEAR....
CENTRAL PARK NY.........96................98............1923....
LAGUARDIA NY............97................96............1953....
KENNEDY NY..............89................93............1995....
NEWARK NJ...............98................97............1953....
ISLIP NY................89................93............1995....
BRIDGEPORT CT...........90................93............1953....
TEMPERATURES FOR JUNE 21...
..LOCATION.........FORECAST HIGH......RECORD HIGH.......YEAR....
CENTRAL PARK NY.........97................97.........1953/1988..
LAGUARDIA NY............99................97............1953....
KENNEDY NY..............95................95............1988....
NEWARK NJ..............100................100...........1953....
ISLIP NY................95................93............1988....
BRIDGEPORT CT...........93................95............1953....
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...HEAT ADVISORY FROM NOON WEDNESDAY TO 8 PM EDT THURSDAY FOR
CTZ005-006-009.
NY...HEAT ADVISORY FROM NOON WEDNESDAY TO 8 PM EDT THURSDAY FOR
NYZ067>075-176>178.
NJ...HEAT ADVISORY FROM NOON WEDNESDAY TO 8 PM EDT THURSDAY FOR
NJZ002-004-006-103>108.
MARINE...NONE.
&&
$$
SYNOPSIS...BC/NV
NEAR TERM...BC/PW
SHORT TERM...BC
LONG TERM...NV
AVIATION...MPS/12
MARINE...BC/NV
HYDROLOGY...BC/NV
CLIMATE...
AREA FORECAST DISCUSSION
NWS POCATELLO ID
217 PM MDT MON JUN 18 2012
.DISCUSSION...UPPER LOW CURRENTLY OVER WASHINGTON CONTINUING TO
MOVE EAST PER WV SAT IMAGERY. CU FIELD SPREADING INTO THE CENTRAL
MOUNTAINS AHEAD OF MAIN TROUGH AXIS. WEAK STRATOCU FIELD HAS
PUSHED THROUGH PORTIONS OF THE SNAKE PLAIN AND SOUTHERN/EASTERN
HIGHLANDS TODAY WHICH HAS SOMEWHAT LIMITED DIURNAL MIXING. THUS
THE WINDS HAVE REMAINED SLIGHTLY LOWER THAN FORECAST. WINDS ACROSS
THE ARCO DESERT HAVE STRENGTHENED INTO THE HIGH WIND CATEGORY.
WINDS THROUGH REMAINDER OF WARNED AREA SHOULD INCREASE AS CLOUDS
MOVE THROUGH. HRRR MODEL INDICATES PEAK SPEEDS OCCURING BETWEEN
21Z AND 00Z THIS AFTERNOON WITH SWIFT DROPOFF DURING THE EVENING. MAIN
TROUGH AXIS KICKS PAST EASTERN IDAHO THIS EVENING BUT LEAVES BROAD
TROUGH IN PLACE OVER THE PACNW. SECOND WEAKER SHORTWAVE MOVES
THROUGH TROUGH ON TUESDAY BUT JET PUSHED FURTHER SOUTH SO WINDS
EXPECTED TO BE LESS OF A CONCERN. LAKE WIND ADVISORY MAY BE
NECESSARY BUT WILL LEAVE FOR LATER SHIFTS AFTER CURRENT WIND EVENT
IS OVER.
UPPER RIDGE BUILDS INTO THE REGION WEDNESDAY AND BEYOND AS DEEP
LOW DEVELOPS OFF PACNW COAST. GENERAL MODEL CONSENSUS HOLDS CENTER
OF UPPER LOW OFF WASHINGTON/OREGON COAST FRIDAY THROUGH SUNDAY.
MODELS DIFFER IN HOW MUCH MOISTURE SPREADS INLAND...LEAVING
EASTERN IDAHO ON THE FRINGE OF POTENTIAL CONVECTIVE ACTIVITY EACH
DAY. SOUTHWEST FLOW ALOFT SHOULD HOLD TEMPS FAIRLY STABLE THROUGH
THE EXTENDED RANGE. OVERALL MADE ONLY A FEW MINOR ADJUSTMENTS TO
CURRENT FORECAST. DMH
&&
.AVIATION...THE STRONG WINDS ACROSS THE AREA TODAY WILL SUBSIDE LATE
THIS EVENING. VFR CONDITIONS ARE FORECAST THROUGH TUESDAY WITH MID
LEVEL CLOUD COVER ACROSS EASTERN IDAHO. ANY REAL THREAT OF SHOWERS
AND THUNDERSTORMS WILL REMAIN CONFINED TO AREAS ALONG THE MONTANA
AND WYOMING BORDERS. KEYES
&&
.FIRE WEATHER...A STORM SYSTEM WILL CONTINUE TO SHIFT EAST ACROSS
THE PANHANDLE AND INTO MONTANA IN THE NEXT 24 HOURS. ISOLATED TO
WIDELY SCATTERED SHOWERS AND STORMS WILL BE CONFINED TO CLOSER TO
THE MONTANA AND WYOMING BORDERS THROUGH TONIGHT...THEN JUST THE
MONTANA BORDER TUESDAY. THE STORY IS THE STRONG WINDS AND LOW
HUMIDITY FOUND ACROSS MUCH OF THE AREA TODAY. WE WILL SEE WINDS
RAPIDLY DECREASE THIS EVENING ALONG WITH RISING HUMIDITY VALUES. THE
RED FLAG WARNINGS FOR PORTIONS OF ZONES 409/410/411/412 ARE STILL
VALID THROUGH 9PM. WE WILL LOCALLY BREEZY CONDITIONS TOMORROW BUT NO
RED FLAG ISSUES AS HUMIDITIES WILL BE UP DESPITE GUSTY WINDS.
MIDWEEK WILL BE MUCH DRIER AND WARMER UNDER HIGH PRESSURE. WE WILL
SEE RAPID DRYING EVEN AT HIGHER ELEVATIONS...SO EXPECT POOR
NIGHTTIME RECOVERY AT RIDGETOP. WHILE MORE PRECISE DETAILS ON WHERE
POTENTIAL SHOWERS AND STORMS WILL BE FORMING BY THE WEEKEND...IT
DOES APPEAR A DISTINCT PATTERN SHIFT TOWARD SOUTHWEST/MONSOON FLOW
IS COMING. KEYES
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING IDZ410-411.
WIND ADVISORY UNTIL 9 PM MDT THIS EVENING IDZ017-019-021>023-032.
HIGH WIND WARNING UNTIL 9 PM MDT THIS EVENING IDZ020.
RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING IDZ409-412.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
633 AM CDT MON JUN 18 2012
.UPDATE...
CLOUD COVER FROM THE MCS IS A BIT THICKER THAN EARLIER THOUGHT BUT
SATELLITE SHOWS CLEARING OCCURRING FROM THE WEST. STRONG SOUTHWEST
FLOW AND RELATIVELY DRY GROUND WILL ALLOW TEMPERATURES TO CLIMB
QUICKLY DURING THE DAY. REFER TO THE CLIMATE SECTION AS
TEMPERATURES MAY BE CLOSE TO RECORDS FOR SOME LOCATIONS.
WINDS SHOULD PICK UP CONSIDERABLE BETWEEN 9 AND 11 AM AS THE
INVERSION BREAKS.
RAP TRENDS SHOW CONVECTIVE TEMPERATURES NORTH OF 100 DEGREES THIS
AFTERNOON SO DRY CONDITIONS ARE EXPECTED. IF CURRENT TRENDS FROM
THE MODELS ARE CORRECT...THE EXPECTED CONVECTION THIS AFTERNOON
MAY BE FURTHER NORTH ALONG THE MN/IA BORDER WHERE THE EDGE OF THE
CAP IS BEING SUGGESTED. A WEAKNESS IN THE CAP IS SUGGESTED THIS
EVENING OVER EXTREME NORTHEAST IOWA/SOUTHEAST MINNESOTA WHICH MAY
BE DUE TO CONVECTION. MCS AND LIFT TOOLS ARE NOW SUGGESTING
CONVECTION MAY BE JUST NORTH OF THE CWFA WITH THE HWY 20 CORRIDOR
POSSIBLY REMAINING DRY. ..08..
&&
.AVIATION...
VFR WX WILL BE SEEN THROUGH 12Z/19. STORM SYSTEM MOVING INTO
MINNESOTA WILL PRODUCE STRONG WINDS ONCE THE INVERSION BREAKS
AROUND 15Z/18. SUSTAINED WINDS 20-25 KTS WITH GUSTS OF 30 KTS OR
HIGHER ARE EXPECTED. KDBQ MAY HAVE A CB VISIBLE IN THE SKY AFT
00Z/19 BUT IT SHOULD NOT IMPACT THE AIRPORT. ..08..
&&
.CLIMATE...
RECORD HIGHS FOR JUNE 18...
MOLINE.........98 IN 1994
CEDAR RAPIDS...99 IN 1913
DUBUQUE........96 IN 1887
BURLINGTON.....97 IN 1953
&&
.PREV DISCUSSION... /ISSUED 336 AM CDT MON JUN 18 2012/
SYNOPSIS...
06Z SFC ANALYSIS HAS A LOW NEAR KVTN WITH A WARM FRONT INTO
NORTHWEST IOWA. MESO HIGHS AND LOWS ASSOCIATED WITH THE MCS
CROSSING THE MISSISSIPPI INTO WISCONSIN WERE ACROSS MN/WI. A
FRONT/BOUNDARY RAN FROM CENTRAL WISCONSIN INTO NORTHERN INDIANA.
DEW POINTS WERE IN THE 60S ACROSS THE MIDWEST WITH 50S OVER THE
IMMEDIATE GREAT LAKES REGION.
SHORT TERM...TODAY AND TONIGHT
THE CONCERNS TODAY ARE MANY. REFER TO THE CLIMATE SECTION FOR
RECORD HIGHS FOR JUNE 18TH.
FIRST...BASED ON RADAR TRENDS AND RAP MODEL TRENDS THE MCS OVER
WISCONSIN WILL MISS THE CWFA. THUS THE MORNING HOURS WILL BE DRY.
SKIES WILL CLEAR OUT AS THE MCS MOVES FURTHER EAST AND WINDS WILL
INCREASE AS THE INVERSION BREAKS.
A WIND ADVISORY WILL BE IN EFFECT THIS AFTERNOON FOR THE ENTIRE
AREA. THE ADVISORY WILL LIKELY BE MARGINAL FOR MUCH OF THE AREA
BUT DEEP MIXING SHOULD ALLOW GUSTS OF 40 TO 45 MPH.
THE NEXT PROBLEM IS TEMPERATURES AND A POSSIBLE HEADLINE FOR HEAT.
BASED ON THE SOURCE REGION FROM YESTERDAY AND THE WARM START THIS
MORNING MAX TEMPERATURES SHOULD BE IN THE 92 TO 96 RANGE ACROSS
THE AREA. FAVORED WARM AREAS WILL LIKELY SEE UPPER 90S. DEEP
MIXING THIS AFTERNOON SHOULD RESULT IN DEW POINTS DROPPING A FEW
DEGREES BUT SHOULD REMAIN IN THE 64 TO 68 DEGREE RANGE. BASED ON
THIS AFTERNOON HEAT INDICES WILL BE AT OR A LITTLE ABOVE 100
DEGREES.
CONSIDERABLE THOUGHT WENT INTO WHETHER OR NOT TO GO WITH HEAT
HEADLINES. FIRST...THE CRITERIA OF 100 WILL BE ACHIEVED OVER A
GOOD CHUNK OF THE CWFA. HOWEVER...YESTERDAY WAS NOT OVERLY WARM
AND HEAT RELATED PROBLEMS ARE ACCUMULATIVE OVER SEVERAL DAYS.
SINCE TODAY WILL BE THE FIRST DAY OF REALLY HOT WX THE DECISION
WAS TO HOLD OFF ON ISSUING HEAT HEADLINES. HEAT HEADLINES MAY NEED
TO BE REVISITED AS THE DAY PROGRESSES...ESPECIALLY IF DEW POINTS
REMAIN HIGHER THAN FCST.
TONIGHT...THE QUESTION IS WHERE WILL THE CONVECTION FIRE. MCS AND
LIFT TOOLS SUGGEST NORTHERN IOWA NEAR THE IA/MN BORDER AT THE EDGE
OF THE CAP. CORFIDI VECTORS WOULD THEN TAKE ANY CONVECTION THAT
DEVELOPS EAST WITH PERHAPS A SLOW PROPAGATION DRIFT TO THE SOUTH.
THEREFORE...WILL CONTINUE WITH THE SCHC POPS IN THE HWY 20
CORRIDOR WHICH IS NEAR THE EDGE OF THE CAP. MIN TEMPERATURES
TONIGHT WILL BE QUITE WARM WITH LOWS OF 70 TO 75. ..08..
LONG TERM...TUESDAY THROUGH SUNDAY...
MAIN FORECAST CONCERNS ARE THE COLD FRONTAL PASSAGE AND POTENTIAL
FOR SEVERE WEATHER AND MUCH NEEDED RAINFALL LATE WEDNESDAY INTO
THURSDAY...AND THE NEXT WARM AND COLD FRONTAL PASSAGES THIS WEEKEND.
TUESDAY LOOKS TO BE A NEAR REPEAT OF MONDAY WITH A LITTLE LESS HEAT
AND WIND AS WE CONTINUE TO BAKE IN THE WARM SECTOR. THEN THINGS GET
INTERESTING WEDNESDAY.
MODELS INDICATE A LATE DAY FRONTAL PASSAGE WITH THE 00Z NAM THE
FASTEST AND 12Z/00Z ECMWF THE SLOWEST. THE NAM BRINGS THE FRONT
INTO THE NORTHWEST PART OF THE CWA RIGHT AT PEAK HEATING. THUS IT
INDICATES THE HIGHEST THREAT OF SEVERE WEATHER WITH SUFFICIENT CAPE
AND SHEAR FOR ORGANIZED CONVECTION...POSSIBLY IN THE FORM OF A
SQUALL LINE GIVEN THE NATURE OF LOW-LEVEL FORCING.
THE ECMWF INDICATES MORE OF A LATE EVENING FRONTAL PASSAGE AND THE
GFS IS IN BETWEEN. BOTH THE GFS AND ECMWF SHOW A MARKED DIURNAL
IMPACT ON CAPE WITH INSTABILITY...AND THUS THE SEVERE THREAT...
DECREASING RAPIDLY AFTER 00Z. GFS CAPES LOOK TOO HIGH TO BEGIN WITH
GIVEN ISSUES WITH OVERDONE LOW-LEVEL MOISTURE THAT HAS BEEN
COMMONPLACE OF LATE. WILL MENTION SEVERE POTENTIAL IN THE HWO...BUT
AVOID DETAILS UNTIL THE PICTURE CLARIFIES.
GIVEN THE DRY WEATHER OF RECENT WEEKS...INTEREST IS QPF POTENTIAL IS
HIGH. FORECAST PW VALUES ARE BETWEEN 1.5 AND 2 INCHES...THOUGH
AGAIN THE HIGHER VALUES IN THE GFS ARE LIKELY OVERDONE. GIVEN THE
NAM FORECAST...QPF COULD BE LOCALLY HIGH WITH 1.5 INCH PW VALUES AT
150% OF NORMAL...BUT THE PROGRESSIVE NATURE OF THE FRONT MIGHT
NEGATE THE POTENTIAL FOR A BROAD AREA OF REALLY DECENT RAINFALL THAT
WOULD TAKE THE EDGE OFF OF THE DRYNESS. CLIMATOLOGICALLY WE AVERAGE
A LITTLE MORE THAN 1 INCH OF RAIN A WEEK...OR ABOUT 4.5 INCHES FOR
THE MONTH...SO WE MAY DO LITTLE MORE THAN TREAD WATER IN THIS EVENT
IN MOST AREAS.
ONCE THE FRONT EXITS THE CWA BY MIDDAY THURSDAY...A PERIOD OF DRY
WEATHER SHOULD PREVAIL UNTIL THE FRONT RETURNS AS A WARM FRONT
FRIDAY NIGHT INTO SATURDAY. BOTH THE GFS AND ECMWF INDICATE A
SHORTWAVE PHASING WITH THE FRONT LIFTING NORTHEAST THROUGH OUR
CWA...SO HAVE CHANCE POPS IN THE FORECAST.
THE GFS AND 12Z AND 00Z ECMWF DROP A BACKDOOR COLD FRONT INTO THE
AREA SUNDAY AS SURFACE HIGH PRESSURE DROPS DOWN LAKE MICHIGAN...
PUTTING US IN EASTERLY FLOW. COLLABORATED WITH NEIGHBORING OFFICES
AND REFLECTED THESE CHANGES IN MAX TEMPS AND WIND FORECASTS.
WOLF
AVIATION...
VFR WX WILL BE SEEN THROUGH 00Z/19. WINDS WILL INCREASE
SIGNIFICANTLY AFT 14Z/18 AS THE INVERSION BREAKS WITH GUSTS OF 30
TO 35 KTS EXPECTED. AFT 00Z/19 THERE IS A LOW POSSIBILITY OF VCTS
OCCURRING AT KDBQ. THE CURRENT THINKING IS TO LEAVE THIS OUT OF
THE 12Z TAFS AND SEE HOW POSSIBLE CONVECTION DEVELOPS LATER TODAY.
THUS VFR WX IS EXPECTED AFT 00Z/19. ..08..
CLIMATE...
RECORD HIGHS FOR JUNE 18...
MOLINE.........98 IN 1994
CEDAR RAPIDS...99 IN 1913
DUBUQUE........96 IN 1887
BURLINGTON.....97 IN 1953
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...WIND ADVISORY FROM NOON TODAY TO 7 PM CDT THIS EVENING FOR
BENTON-BUCHANAN-CEDAR-CLINTON-DELAWARE-DES MOINES-DUBUQUE-
HENRY IA-IOWA-JACKSON-JEFFERSON-JOHNSON-JONES-KEOKUK-LEE-
LINN-LOUISA-MUSCATINE-SCOTT-VAN BUREN-WASHINGTON.
IL...WIND ADVISORY FROM NOON TODAY TO 7 PM CDT THIS EVENING FOR
BUREAU-CARROLL-HANCOCK-HENDERSON-HENRY IL-JO DAVIESS-
MCDONOUGH-MERCER-PUTNAM-ROCK ISLAND-STEPHENSON-WARREN-
WHITESIDE.
MO...WIND ADVISORY FROM NOON TODAY TO 7 PM CDT THIS EVENING FOR CLARK-
SCOTLAND.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
336 AM CDT MON JUN 18 2012
.SYNOPSIS...
06Z SFC ANALYSIS HAS A LOW NEAR KVTN WITH A WARM FRONT INTO
NORTHWEST IOWA. MESO HIGHS AND LOWS ASSOCIATED WITH THE MCS
CROSSING THE MISSISSIPPI INTO WISCONSIN WERE ACROSS MN/WI. A
FRONT/BOUNDARY RAN FROM CENTRAL WISCONSIN INTO NORTHERN INDIANA.
DEW POINTS WERE IN THE 60S ACROSS THE MIDWEST WITH 50S OVER THE
IMMEDIATE GREAT LAKES REGION.
&&
.SHORT TERM...TODAY AND TONIGHT
THE CONCERNS TODAY ARE MANY. REFER TO THE CLIMATE SECTION FOR
RECORD HIGHS FOR JUNE 18TH.
FIRST...BASED ON RADAR TRENDS AND RAP MODEL TRENDS THE MCS OVER
WISCONSIN WILL MISS THE CWFA. THUS THE MORNING HOURS WILL BE DRY.
SKIES WILL CLEAR OUT AS THE MCS MOVES FURTHER EAST AND WINDS WILL
INCREASE AS THE INVERSION BREAKS.
A WIND ADVISORY WILL BE IN EFFECT THIS AFTERNOON FOR THE ENTIRE
AREA. THE ADVISORY WILL LIKELY BE MARGINAL FOR MUCH OF THE AREA
BUT DEEP MIXING SHOULD ALLOW GUSTS OF 40 TO 45 MPH.
THE NEXT PROBLEM IS TEMPERATURES AND A POSSIBLE HEADLINE FOR HEAT.
BASED ON THE SOURCE REGION FROM YESTERDAY AND THE WARM START THIS
MORNING MAX TEMPERATURES SHOULD BE IN THE 92 TO 96 RANGE ACROSS
THE AREA. FAVORED WARM AREAS WILL LIKELY SEE UPPER 90S. DEEP
MIXING THIS AFTERNOON SHOULD RESULT IN DEW POINTS DROPPING A FEW
DEGREES BUT SHOULD REMAIN IN THE 64 TO 68 DEGREE RANGE. BASED ON
THIS AFTERNOON HEAT INDICES WILL BE AT OR A LITTLE ABOVE 100
DEGREES.
CONSIDERABLE THOUGHT WENT INTO WHETHER OR NOT TO GO WITH HEAT
HEADLINES. FIRST...THE CRITERIA OF 100 WILL BE ACHIEVED OVER A
GOOD CHUNK OF THE CWFA. HOWEVER...YESTERDAY WAS NOT OVERLY WARM
AND HEAT RELATED PROBLEMS ARE ACCUMULATIVE OVER SEVERAL DAYS.
SINCE TODAY WILL BE THE FIRST DAY OF REALLY HOT WX THE DECISION
WAS TO HOLD OFF ON ISSUING HEAT HEADLINES. HEAT HEADLINES MAY NEED
TO BE REVISITED AS THE DAY PROGRESSES...ESPECIALLY IF DEW POINTS
REMAIN HIGHER THAN FCST.
TONIGHT...THE QUESTION IS WHERE WILL THE CONVECTION FIRE. MCS AND
LIFT TOOLS SUGGEST NORTHERN IOWA NEAR THE IA/MN BORDER AT THE EDGE
OF THE CAP. CORFIDI VECTORS WOULD THEN TAKE ANY CONVECTION THAT
DEVELOPS EAST WITH PERHAPS A SLOW PROPAGATION DRIFT TO THE SOUTH.
THEREFORE...WILL CONTINUE WITH THE SCHC POPS IN THE HWY 20
CORRIDOR WHICH IS NEAR THE EDGE OF THE CAP. MIN TEMPERATURES
TONIGHT WILL BE QUITE WARM WITH LOWS OF 70 TO 75. ..08..
.LONG TERM...TUESDAY THROUGH SUNDAY...
MAIN FORECAST CONCERNS ARE THE COLD FRONTAL PASSAGE AND POTENTIAL
FOR SEVERE WEATHER AND MUCH NEEDED RAINFALL LATE WEDNESDAY INTO
THURSDAY...AND THE NEXT WARM AND COLD FRONTAL PASSAGES THIS WEEKEND.
TUESDAY LOOKS TO BE A NEAR REPEAT OF MONDAY WITH A LITTLE LESS HEAT
AND WIND AS WE CONTINUE TO BAKE IN THE WARM SECTOR. THEN THINGS GET
INTERESTING WEDNESDAY.
MODELS INDICATE A LATE DAY FRONTAL PASSAGE WITH THE 00Z NAM THE
FASTEST AND 12Z/00Z ECMWF THE SLOWEST. THE NAM BRINGS THE FRONT
INTO THE NORTHWEST PART OF THE CWA RIGHT AT PEAK HEATING. THUS IT
INDICATES THE HIGHEST THREAT OF SEVERE WEATHER WITH SUFFICIENT CAPE
AND SHEAR FOR ORGANIZED CONVECTION...POSSIBLY IN THE FORM OF A
SQUALL LINE GIVEN THE NATURE OF LOW-LEVEL FORCING.
THE ECMWF INDICATES MORE OF A LATE EVENING FRONTAL PASSAGE AND THE
GFS IS IN BETWEEN. BOTH THE GFS AND ECMWF SHOW A MARKED DIURNAL
IMPACT ON CAPE WITH INSTABILITY...AND THUS THE SEVERE THREAT...
DECREASING RAPIDLY AFTER 00Z. GFS CAPES LOOK TOO HIGH TO BEGIN WITH
GIVEN ISSUES WITH OVERDONE LOW-LEVEL MOISTURE THAT HAS BEEN
COMMONPLACE OF LATE. WILL MENTION SEVERE POTENTIAL IN THE HWO...BUT
AVOID DETAILS UNTIL THE PICTURE CLARIFIES.
GIVEN THE DRY WEATHER OF RECENT WEEKS...INTEREST IS QPF POTENTIAL IS
HIGH. FORECAST PW VALUES ARE BETWEEN 1.5 AND 2 INCHES...THOUGH
AGAIN THE HIGHER VALUES IN THE GFS ARE LIKELY OVERDONE. GIVEN THE
NAM FORECAST...QPF COULD BE LOCALLY HIGH WITH 1.5 INCH PW VALUES AT
150% OF NORMAL...BUT THE PROGRESSIVE NATURE OF THE FRONT MIGHT
NEGATE THE POTENTIAL FOR A BROAD AREA OF REALLY DECENT RAINFALL THAT
WOULD TAKE THE EDGE OFF OF THE DRYNESS. CLIMATOLOGICALLY WE AVERAGE
A LITTLE MORE THAN 1 INCH OF RAIN A WEEK...OR ABOUT 4.5 INCHES FOR
THE MONTH...SO WE MAY DO LITTLE MORE THAN TREAD WATER IN THIS EVENT
IN MOST AREAS.
ONCE THE FRONT EXITS THE CWA BY MIDDAY THURSDAY...A PERIOD OF DRY
WEATHER SHOULD PREVAIL UNTIL THE FRONT RETURNS AS A WARM FRONT
FRIDAY NIGHT INTO SATURDAY. BOTH THE GFS AND ECMWF INDICATE A
SHORTWAVE PHASING WITH THE FRONT LIFTING NORTHEAST THROUGH OUR
CWA...SO HAVE CHANCE POPS IN THE FORECAST.
THE GFS AND 12Z AND 00Z ECMWF DROP A BACKDOOR COLD FRONT INTO THE
AREA SUNDAY AS SURFACE HIGH PRESSURE DROPS DOWN LAKE MICHIGAN...
PUTTING US IN EASTERLY FLOW. COLLABORATED WITH NEIGHBORING OFFICES
AND REFLECTED THESE CHANGES IN MAX TEMPS AND WIND FORECASTS.
WOLF
&&
.AVIATION...
VFR WX WILL BE SEEN THROUGH 00Z/19. WINDS WILL INCREASE
SIGNIFICANTLY AFT 14Z/18 AS THE INVERSION BREAKS WITH GUSTS OF 30
TO 35 KTS EXPECTED. AFT 00Z/19 THERE IS A LOW POSSIBILITY OF VCTS
OCCURRING AT KDBQ. THE CURRENT THINKING IS TO LEAVE THIS OUT OF
THE 12Z TAFS AND SEE HOW POSSIBLE CONVECTION DEVELOPS LATER TODAY.
THUS VFR WX IS EXPECTED AFT 00Z/19. ..08..
&&
.CLIMATE...
RECORD HIGHS FOR JUNE 18...
MOLINE.........98 IN 1994
CEDAR RAPIDS...99 IN 1913
DUBUQUE........96 IN 1887
BURLINGTON.....97 IN 1953
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...WIND ADVISORY FROM NOON TODAY TO 7 PM CDT THIS EVENING FOR
BENTON-BUCHANAN-CEDAR-CLINTON-DELAWARE-DES MOINES-DUBUQUE-
HENRY IA-IOWA-JACKSON-JEFFERSON-JOHNSON-JONES-KEOKUK-LEE-
LINN-LOUISA-MUSCATINE-SCOTT-VAN BUREN-WASHINGTON.
IL...WIND ADVISORY FROM NOON TODAY TO 7 PM CDT THIS EVENING FOR
BUREAU-CARROLL-HANCOCK-HENDERSON-HENRY IL-JO DAVIESS-
MCDONOUGH-MERCER-PUTNAM-ROCK ISLAND-STEPHENSON-WARREN-
WHITESIDE.
MO...WIND ADVISORY FROM NOON TODAY TO 7 PM CDT THIS EVENING FOR CLARK-
SCOTLAND.
&&
$$
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
945 PM CDT TUE JUN 19 2012
.DISCUSSION...
WIDELY SCT CONVECTION CONTINUES TO WANE THIS EVENING WITH THE
DECREASE IN LOW LEVEL INSTABILITY...WITH ONLY ISOLATED -SHRA
REMAINING ACROSS ACROSS RED RIVER COUNTY TX...AS WELL AS CNTRL LA
AND SW AR. THE EVENING WATER VAPOR LOOP REVEALS OUR WEAK INVERTED
SHEAR AXIS EXTENDING FROM NEAR THE RED RIVER VALLEY OF NE TX SSW
INTO ECNTRL AND S TX...WHICH MAY DRIFT A TAD FARTHER W TOWARDS THE
I-35 CORRIDOR LATE BEFORE PULLING UP STATIONARY WEDNESDAY. THE 00Z
NAM AND LATEST RUC INDICATE A MID LEVEL THETA-E RIDGE PERSISTING
ACROSS SE OK/E TX OVERNIGHT...IN VC OF A 25-30 KT SRLY LLJ THAT
DEVELOPS JUST E OF THE PRIMARY SHEAR AXIS. GIVEN THE MYRIAD OF
REMNANT OUTFLOW BOUNDARIES THAT LINGER ACROSS THESE AREAS...HAVE
EXTENDED SLIGHT CHANCE POPS OVERNIGHT AS ADDITIONAL REDEVELOPMENT
MAY BE POSSIBLE...GIVEN THE NEARLY TROPICAL AIR MASS IN PLACE /PER
THE 00Z KSHV RAOB PW JUST UNDER 2 INCHES/. DRIER AIR TO THE E AND
SE /AS INDICATED ON THE 00Z KLIX/KJAN RAOBS/ WILL BEGIN TO ADVECT
NW INTO SCNTRL AR/NCNTRL LA OVERNIGHT...AND FARTHER W ACROSS THE
REGION WEDNESDAY...THUS DIMINISHING RAIN CHANCES OVER ALL BUT
PORTIONS OF E TX CLOSER TO THE SHEAR AXIS.
STILL SEEING A CONSIDERABLE AMOUNT OF CONVECTIVE DEBRIS OVER MUCH
OF THE REGION THIS EVENING...BUT THIS SHOULD GRADUALLY THIN A BIT
OVERNIGHT ESPECIALLY OVER THE ERN SECTIONS OF THE REGION. THIS
CLOUD COVER AND A WEAK PRESSURE GRADIENT MAY ALSO LIMIT THE EXTENT
OF THE TEMP FALL OVERNIGHT...DESPITE MUCH OF THE AREA BEING RAIN
COOLED. THUS...HAVE BUMPED UP THE MIN TEMP FORECAST SLIGHTLY FOR E
TX/WRN LA...BUT SHOULD NOT HAVE ANY SENSIBLE WORDING CHANGES TO
THE GOING FORECAST. OTHERWISE...THE CURRENT FORECAST IS ON TRACK.
ZONE UPDATE ALREADY OUT...GRIDS WILL BE AVAILABLE SHORTLY.
15
&&
.AVIATION...
CONCERNING THE ARKLATEX...ISOLD TSTMS ENDING AND OUR TERMINALS ARE
FAIR FOR THE EVENING UNDER A VEIL OF CIRRUS...BUT WITH MVFR/IFR CIGS
AGAIN BY SUNRISE AND THEN RAINFALL FROM TODAY/S STORMS MAY ALSO
ALLOW FOR PATCHY FOG TO DEVELOP AT ANY OF OUR SITES EXCEPT KMLU
WHERE RAIN DID NOT FALL. S/SE SFC WINDS OVERNIGHT WILL INCREASE BY
MID MORNING TO AROUND 10 KTS WITH A FLAT SCT CU FIELD TO FOLLOW.
ISOLD TSTMS POSSIBLE OVER EAST TEXAS 21-24Z...BUT MAYBE BE JUST TO
OUR W. ALOFT...SOUTHERLY FLOW 20-30 KTS IS SUPER DEEP TO 36KFT. /24/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 72 92 71 93 70 / 10 10 10 10 10
MLU 71 92 70 93 69 / 10 10 10 10 10
DEQ 70 92 67 93 68 / 20 10 10 20 20
TXK 71 93 68 92 70 / 20 10 10 10 20
ELD 70 92 67 92 67 / 10 10 10 10 10
TYR 73 90 71 91 72 / 20 20 10 10 10
GGG 72 92 70 91 69 / 20 20 10 10 10
LFK 73 91 70 92 70 / 20 20 10 10 0
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
15/24
AREA FORECAST DISCUSSION
NWS CARIBOU ME
926 PM EDT TUE JUN 19 2012
.SYNOPSIS...
A WEAK COLD FRONT WILL ACROSS THE REGION WEDNESDAY. A WARM FRONT
WILL THEN CROSS THE STATE ON THURSDAY FOLLOWED BY ANOTHER COLD FRONT ON
FRIDAY.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
925 PM UPDATE: FOG AND STRATUS HAS MOVED IN FROM THE OCEAN OVER THE
COASTAL AREAS. EXPECT THE FOG AND STRATUS TO CONTINUE TO MOVE
NORTH TONIGHT.
630 PM UPDATE: SHOWERS ACROSS NORTHERN MAINE HAVE DISSIPATED EARLY
THIS EVENING AS WEAK IMPULSE SHEARS APART AS IT RIDES THROUGH THE
UPPER RIDGE. NEAR TERM MODELS (HRRR/RUC) INDICATE SHOWERS POSSIBLE
AFTER MIDNIGHT AS ANOTHER WEAK IMPULSE MOVES ACROSS THE NORTHERN
EDGE OF THE UPPER RIDGE SO WILL KEEP LOW CHANCE TO ISOLATED POPS
FOR LATER TONIGHT IN THE FORECAST.
PREVIOUS DISCUSSION:
CHALLENGES THIS TERM WILL BE CONVECTION AND STRATUS.
ATTM, NOT OVERLY IMPRESSED W/THE POTENTIAL FOR TSTMS TO FIRE UP
ACROSS THE NORTHERN AND WESTERN CWA.
LATEST RUC SOUNDINGS DO SUPPORT SB CAPES OF 700+ JOULES
W/MOISTURE UP THROUGH 700 MBS ACROSS THE FAR W AND N BUT AS THE
AFTERNOON WEARS ON AND EVENING APCHS, THE MOISTURE IS LIMITED TO
850MBS AND BELOW AND ATMOSPHERE STABILIZES IN THE LLVLS. MID LEVEL
LAPSE RATES ARE CLOSE TO 6.0 C/KM AND HOLD THERE THROUGH THE
NIGHT. THERE IS SOME MID LEVEL FORCING INITIALLY BUT THAT IS GONE
BY 06Z AS THE FRONT APCHS. ATTM, DECIDED ON ISOLD TSTMS AND KEPT
POPS NO MORE THAN 40% ACROSS THE FAR N AND W FOR SHOWERS.
SKY COVER WILL BE A CHALLENGE TONIGHT AS S FLOW INITIALLY WILL
ALLOW FOR STRATUS TO DEVELOP AGAIN LATER THIS EVENING INTO THE
OVERNIGHT PERIOD ESPECIALLY ACROSS THE DOWNEAST INTO THE CENTRAL
HIGHLANDS INTO THE MLT AND HUL REGIONS. FURTHER N AND W, WIND
VEERING MORE SW OVERNIGHT SHOULD LIMIT PROGRESSION OF THE STRATUS.
FOG POTENTIAL IS HIGHEST OVER THE DOWNEAST AND COAST AND DECIDED
TO KEEP THE MENTION OF FOG IN THERE FOR THESE AREAS. FURTHER N AND
W, KEPT FOG OUT DUE TO WIND SPEEDS STAYING UP FOR ONE AND DIRECTION
MORE WSW BY MORNING. THIS WILL ALSO KEEP TEMPERATURES UP WITH
READINGS SOME 5 DEGREES WARMER THAN THEY WERE LAST NIGHT AND EARLY
THIS MORNING.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
A SMALL TROUGH OF LOW PRESSURE SLIDING ACROSS THE NORTH WILL MOVE
EAST OF THE AREA ON WEDNESDAY. THIS WILL LEAVE A WEAK FRONTAL
BOUNDARY DRAPED ACROSS THE CENTRAL PART OF THE STATE DIVIDING WARM
AIR TO THE NORTH FROM HOT AND HUMID AIR TO THE SOUTH AND WEST.
SOME MOISTURE WILL CONCENTRATED ALONG THIS BOUNDARY AND A
THUNDERSTORM MAY AFFECT CENTRAL OR DOWNEAST AREAS JUST ALONG OR
SOUTH OF THE FRONTAL BOUNDARY. THE STRONGEST INSTABILITY SEEMS TO
BE DURING THE MIDDAY ACROSS DOWNEAST AREAS AS THE SURFACE TROUGH
PUSHES THROUGH. THE FRONT WILL REMAIN IN PLACE WEDNESDAY NIGHT. A
SMALL LOW LIFTING NORTH AND WEST OF THE AREA ON THURSDAY WILL PULL
THE FRONTAL BOUNDARY BACK NORTH AS A WARM FRONT. MODEL SOUNDINGS
SHOW INCREASING INSTABILITY ALONG AND JUST SOUTHWEST OF THE WARM
FRONT ACROSS THE WESTERN EDGE OF OUR REGION THURSDAY AFTERNOON.
WARMER AND MORE HUMID AIR WILL BE PULLED INTO THE AREA LATE
THURSDAY INTO THURSDAY NIGHT. SOME THUNDERSTORMS MAY FORM ALONG
THE WARM FRONT THURSDAY AFTERNOON OR EVENING WITH THE BEST CHANCES
FOR STORMS IN THE WEST. THURSDAY NIGHT WILL BE A WARM AND HUMID
NIGHT ACROSS THE REGION BEHIND THE WARM FRONT. A COLD FRONT WILL
THEN APPROACH ON FRIDAY BRINGING A GOOD CHANCE FOR SHOWERS AND
THUNDERSTORMS ACROSS THE STATE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
LOW PRESSURE WILL DRAW A COLD FRONT ACROSS THE REGION FRIDAY NIGHT
WITH A CHANCE OF SHOWERS/THUNDERSTORMS DURING THE EVENING...WITH
DIMINISHING SHOWER CHANCES OVERNIGHT. THE LOW WILL REMAIN IN THE
VICINITY OF THE REGION SATURDAY KEEPING A CHANCE OF
SHOWERS/THUNDERSTORMS MOSTLY DURING THE AFTERNOON. A CHANCE OF
SHOWERS WILL LINGER SATURDAY NIGHT WHILE THE LOW MOVES EAST. A
SHOWER/THUNDERSTORM WILL REMAIN POSSIBLE SUNDAY WITH A LINGERING
TROF IN THE WAKE OF THE LOW. SURFACE LOW PRESSURE WILL THEN
DEVELOP TO THE WEST OF THE REGION SUNDAY NIGHT/MONDAY WHILE AN
UPPER LOW MOVES SOUTH TOWARD THE GREAT LAKES REGION. SHOWER
CHANCES WILL INCREASE ACROSS THE REGION SUNDAY NIGHT THROUGH
MONDAY...WITH A STEADIER RAIN DEVELOPING LATER MONDAY. THE
SURFACE/UPPER LOW WILL THEN REMAIN ACROSS WESTERN NEW ENGLAND
MONDAY NIGHT THROUGH TUESDAY KEEPING A STEADY RAIN ACROSS THE
FORECAST AREA. THE RAIN SHOULD TAPER TO SHOWERS TUESDAY NIGHT.
TEMPERATURES SHOULD BE AT NEAR NORMAL LEVELS SATURDAY/SUNDAY...WITH
BELOW NORMAL LEVEL TEMPERATURES MONDAY/TUESDAY.
&&
.AVIATION /01Z WEDNESDAY THROUGH SUNDAY/...
NEAR TERM: VFR ATTM GOING TO MVFR LATER THIS EVENING AND THEN IFR
BY EARLY WEDNESDAY MORNING. BEST CHC FOR IFR WILL BE FROM HUL ON
SOUTH TO BGR AND BHB. CONDITIONS WILL GO VFR AFTER 12Z WEDNESDAY
W/BGR AND BHB TAKING A WHILE LONGER TO IMPROVE.
SHORT TERM: GENERALLY VFR CONDITIONS ARE EXPECTED WEDNESDAY
THROUGH FRIDAY. THE EXCEPTIONS WILL BE IN ANY THUNDERSTORMS
MAINLY LATE THURSDAY INTO FRIDAY AND IN COASTAL FOG LATE
WEDNESDAY NIGHT AND AGAIN LATE THURSDAY NIGHT. FOG MAY LINGER FOR
A WHILE EACH DAY ALONG THE IMMEDIATE COAST. OCCASIONAL MVFR
CONDITIONS ARE POSSIBLE ACROSS THE REGION FRIDAY NIGHT. OCCASIONAL
MVFR CONDITIONS COULD THEN OCCUR WITH ANY SHOWERS OR THUNDERSTORMS
SATURDAY/SUNDAY.
&&
.MARINE...
NEAR TERM: KEPT THE MENTION OF THE SWELL IN THE FCST TONIGHT AS A
8-9 SECOND PERIOD IS OCCURRING ATTM. THE LATEST WAVE GUIDANCE
INCLUDING THE SWAN GUIDANCE IS SHOWING SEAS REACHING 5 FT TONIGHT
W/THE SOUTHERLY SWELL. DECISION WAS TO BRING SEAS UP A FOOT W/A
RANGE OF 3-5 FT TONIGHT. SEAS LOOK LIKE THEY WILL SUBSIDE LATER
WEDNESDAY AS REFERENCED IN THE SHORT TERM AS WINDS GO OFFSHORE.
SHORT TERM: SWELL FROM A SMALL SUBTROPICAL LOW OFF THE COAST OF
NOVA SCOTIA WILL RESULT IN SEAS NEAR 5 FT EARLY WED.
OTHERWISE...WINDS AND SEAS ARE EXPECTED TO BE BELOW SCA THROUGH
THE PERIOD. HUMID AIR MOVING OVER THE WATERS WILL RESULT IN FOG
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...FOSTER/HEWITT
SHORT TERM...BLOOMER
LONG TERM...NORCROSS
AVIATION...FOSTER/HEWITT
MARINE...FOSTER/HEWITT/BLOOMER
AREA FORECAST DISCUSSION
NWS GRAY ME
1153 AM EDT MON JUN 18 2012
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN ANCHORED IN THE GULF OF MAINE THROUGH
TUESDAY. AN ONSHORE FLOW WILL KEEP COASTAL AREAS COOL AND VARIABLY
CLOUDY. A WARM FRONT WILL MOVE THROUGH THE AREA TUESDAY NIGHT,
BRINGING HOT HUMID AIR INTO THE REGION FOR WEDNESDAY AND THURSDAY.
A COOL FRONT WILL MOVE THROUGH THURSDAY NIGHT AND MOVE OFF THE
COAST BY FRIDAY MORNING BRINGING A RETURN TO SOMEWHAT COOLER AND
LESS HUMID CONDITIONS FRIDAY AND INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1150...STRATUS HAS BROKEN UP OVER THE MOUNTAINS AS EXPECTED...BUT
ALSO HAS BROKEN UP IN MANY SPOTS ALONG THE IMMEDIATE COAST. THIS
SEEMS TO BE DUE TO A LITTLE BETTER AND DEEPER MIXING THANKS TO
ENHANCED ONSHORE FLOW DUE TO SEA BREEZE CIRCULATION. ALSO THE WEAK
ESE UPSLOPE IS SUPPORTING THE CLOUDS FURTHER INLAND. SO HAVE
ADJUSTED THE SKY AND SUBSEQUENTLY...THE TEMP GRIDS BASED ON THIS.
ALTHOUGH STILL SHOULD SEE SOME SUN IN MOST AREAS BY MID-AFTERNOON.
0900...THIS UPDATE FINE TUNES THE CLOUD COVER A BIT FOR THIS
MORNING. FOLLOWING LATEST HRRR MODEL FOR CLOUDS...AS IT HANDLED
LOW STRATUS WELL ON SATURDAY AND IS DOING THE BEST WITH IT THIS
MORNING. STARTING TO SEE THE STRATUS THIN AND BREAK UP IN AREAS OF
TERRAIN...AND WILL CONTINUE TO SEE IT BREAK DOWN AS THE MORNING
WEARS ON. MAY NOT START SEEING BREAKS OF SUN ON THE COASTAL PLAIN
UNTIL EARLY AFTERNOON. STILL SHOULD SEE AT LEAST SOME BREAKS OF
SUN FOR A FEW HOURS THIS AFTERNOON...EVEN ON THE COAST....BEFORE
IT ALL COMES BACK ONSHORE THIS EVENING.
PREV DISCUSSION;
A LIGHT COOL AND MOIST ONSHORE FLOW WILL CONTINUE TODAY. ATTM SAT
PIX SHOWING WIDESPREAD LOW CLOUDS AND FOG OVER THE COASTAL WATERS
AND ALONG THE MAINE COASTAL PLAIN...WITH TIME TODAY SOME OF THE
LOW CLOUDS ALONG THE COASTAL AREAS MAY BURN OFF. FURTHER INLAND
MORE SUN EXPECTED SINCE THE LOW STRATUS WILL NOT REACH TO WELL
INLAND. PATCHY EARLY MORNING FOG IS EXPECTED THOUGH IN THE NORMAL
LOW LYING VALLEY AREAS. TEMPS TODAY WILL BE COOL ALONG THE COAST
WITH WARMER TEMPS WELL INLAND. USED A BLEND OF THE MAV/MET TEMPS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
TONIGHT AND TUESDAY THE COOL ONSHORE FLOW WILL CONTINUE. STRATUS
AND AREAS OF FOG WILL ONCE AGAIN MOVE INLAND TONIGHT AND THEN
SLOWLY BURN OFF BY TUESDAY AFTERNOON. TEMPS WILL BE COOLEST ALONG
THE COAST AND WARMER WELL INLAND TUESDAY. USED A BLEND OF THE
MAV/MET TEMPS ONCE AGAIN.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
RIDGING WILL BUILD EASTWARD FROM THE MIDWEST WEDNESDAY AND
THURSDAY AND BRING THE HEAT ALONG WITH IT. TOOK A BLEND OF THE
AVAILABLE GUIDANCE FOR MAX TEMPS DURING THIS TIME.
THEREFORE...EXPECTING 90S FOR MOST LOCATIONS BOTH DAYS. IT/S
POSSIBLE THAT THE IMMEDIATE COAST STAYS COOLER THAN FORECAST
DEPENDING ON THE EXACT WIND DIRECTION AND ANY SUBTLE SNEAKY
BACKDOOR FRONTS WITH THE NWLY FLOW IN PLACE ALOFT...ESPECIALLY
THE MID COAST OF MAINE. IN ADDITION THERE COULD BE A FEW CLOUDS
AROUND ON WEDNESDAY AS PER LATEST ECMWF WITH SHORT WAVE TROUGH
MOVING THROUGH WEDNESDAY MORNING. HOWEVER...HIGHS IN THE 90S SEEMS
ACCEPTABLE FOR MOST AS THE PATTERN FAVORS IT WITH DOWNSLOPING
WINDS...850MB TEMPS AROUND +20C...AND 1000-500MB THICKNESS VALUES
BETWEEN 577 AND 580 DM.
AS FAR AS POPS GO FOR WEDNESDAY THROUGH FRIDAY...THERE/S A SLIGHT
CHANCE OF SHOWERS AND THUNDERSTORMS TUESDAY NIGHT INTO WEDNESDAY
MORNING AS A WEAK SHORT WAVE TROUGH MOVES THROUGH THE MEAN NWLY
FLOW ALOFT. OTHERWISE...THE BALANCE OF WEDNESDAY LOOKS DRY AS DOES
THURSDAY WITH RIDGING IN PLACE. CAN/T COMPLETELY RULE OUT A SPOT
THUNDERSTORM THURSDAY...ESPECIALLY IN THE MOUNTAINS...BUT A
SLIGHTLY BETTER CHANCE OF A SHOWER OR THUNDERSTORMS EXISTS ACROSS
NORTHERN AND WESTERN ZONES THURSDAY NIGHT WITH THE APPROACH OF A
COLD FRONT.
FRONT MOVES OFFSHORE DURING THE DAY ON FRIDAY...HOWEVER...IT
SHOULD STILL REMAIN VERY WARM. TEMPS MAY APPROACH 90 IN SOUTHERN
MAINE INTO SOUTHERN NH. DRY WEATHER EXPECTED THEN.
DRY AND COOLER WEATHER EXPECTED FRIDAY NIGHT THROUGH SATURDAY IN
THE CAA REGIME. MODEL CONSENSUS IS CURRENTLY QUITE GOOD ON
FORECASTING A COOL RAINMAKER FOR SUNDAY AND SUNDAY NIGHT...SO
INCREASED POPS A BIT THEN BUT IT/S STILL PRETTY FAR OUT AND
SUBJECT TO CHANGE.
&&
.AVIATION /16Z MONDAY THROUGH FRIDAY/...
SHORT TERM...AREAS OF IFR OR LIFR CONDS ARE EXPECTED EARLY THIS
MORNING IN STRATUS AND AREAS OF FOG BUT WILL IMPROVE TO VFR BY
THIS AFTERNOON. CONDS WILL ONCE AGAIN LOWER TO IFR OR LIFR
TONIGHT AS LOW CLOUDS AND FOG RETURN ALONG THE COASTAL PLAIN AND
THE ADJACENT INLAND AREAS AS WELL...WELL INLAND MVFR CONDS ARE
POSSIBLE IN AREAS OF STRATUS THAT WILL MOVE WELL INLAND. ON TUESDAY THE
LOW CLOUDS AND FOG WILL ONCE AGAIN BURN OFF BY AFTERNOON OVER MOST
AREAS WITH THE COASTAL LOCATIONS BEING THE LAST TO IMPROVE.
LONG TERM...SOME LOCAL IFR ON FOG AND STRATUS POSSIBLE TUESDAY
NIGHT...ESPECIALLY ALONG THE COAST. THEREAFTER...MAINLY VFR
CONDITIONS ARE EXPECTED WEDNESDAY THROUGH FRIDAY.
&&
.MARINE...
SHORT TERM...HIGH PRESSURE AND LIGHT WINDS WILL REMAIN OVER THE
WATERS THROUGH TUESDAY. WIDESPREAD FOG CAN BE EXPECTED OVER THE
OUTER WATERS AND AREAS OF FOG IN THE BAYS TODAY THROUGH TUESDAY
RESTRICTING VISIBILITIES.
LONG TERM...MARGINAL SCA SEAS POSSIBLE ON THE OCEAN TUESDAY NIGHT
INTO EARLY WEDNESDAY. OTHERWISE...SUB-SCA CONDITIONS EXPECTED
THROUGH FRIDAY.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...CEMPA
SHORT TERM...
LONG TERM...
AVIATION...
MARINE...
AREA FORECAST DISCUSSION
NWS GRAY ME
903 AM EDT MON JUN 18 2012
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN ANCHORED IN THE GULF OF MAINE THROUGH
TUESDAY. AN ONSHORE FLOW WILL KEEP COASTAL AREAS COOL AND VARIABLY
CLOUDY. A WARM FRONT WILL MOVE THROUGH THE AREA TUESDAY NIGHT,
BRINGING HOT HUMID AIR INTO THE REGION FOR WEDNESDAY AND THURSDAY.
A COOL FRONT WILL MOVE THROUGH THURSDAY NIGHT AND MOVE OFF THE
COAST BY FRIDAY MORNING BRINGING A RETURN TO SOMEWHAT COOLER AND
LESS HUMID CONDITIONS FRIDAY AND INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
0900...THIS UPDATE FINE TUNES THE CLOUD COVER A BIT FOR THIS
MORNING. FOLLOWING LATEST HRRR MODEL FOR CLOUDS...AS IT HANDLED
LOW STRATUS WELL ON SATURDAY AND IS DOING THE BEST WITH IT THIS
MORNING. STARTING TO SEE THE STRATUS THIN AND BREAK UP IN AREAS OF
TERRAIN...AND WILL CONTINUE TO SEE IT BREAK DOWN AS THE MORNING
WEARS ON. MAY NOT START SEEING BREAKS OF SUN ON THE COASTAL PLAIN
UNTIL EARLY AFTERNOON. STILL SHOULD SEE AT LEAST SOME BREAKS OF
SUN FOR A FEW HOURS THIS AFTERNOON...EVEN ON THE COAST....BEFORE
IT ALL COMES BACK ONSHORE THIS EVENING.
PREV DISCUSSION;
A LIGHT COOL AND MOIST ONSHORE FLOW WILL CONTINUE TODAY. ATTM SAT
PIX SHOWING WIDESPREAD LOW CLOUDS AND FOG OVER THE COASTAL WATERS
AND ALONG THE MAINE COASTAL PLAIN...WITH TIME TODAY SOME OF THE
LOW CLOUDS ALONG THE COASTAL AREAS MAY BURN OFF. FURTHER INLAND
MORE SUN EXPECTED SINCE THE LOW STRATUS WILL NOT REACH TO WELL
INLAND. PATCHY EARLY MORNING FOG IS EXPECTED THOUGH IN THE NORMAL
LOW LYING VALLEY AREAS. TEMPS TODAY WILL BE COOL ALONG THE COAST
WITH WARMER TEMPS WELL INLAND. USED A BLEND OF THE MAV/MET TEMPS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
TONIGHT AND TUESDAY THE COOL ONSHORE FLOW WILL CONTINUE. STRATUS
AND AREAS OF FOG WILL ONCE AGAIN MOVE INLAND TONIGHT AND THEN
SLOWLY BURN OFF BY TUESDAY AFTERNOON. TEMPS WILL BE COOLEST ALONG
THE COAST AND WARMER WELL INLAND TUESDAY. USED A BLEND OF THE
MAV/MET TEMPS ONCE AGAIN.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
RIDGING WILL BUILD EASTWARD FROM THE MIDWEST WEDNESDAY AND
THURSDAY AND BRING THE HEAT ALONG WITH IT. TOOK A BLEND OF THE
AVAILABLE GUIDANCE FOR MAX TEMPS DURING THIS TIME.
THEREFORE...EXPECTING 90S FOR MOST LOCATIONS BOTH DAYS. IT/S
POSSIBLE THAT THE IMMEDIATE COAST STAYS COOLER THAN FORECAST
DEPENDING ON THE EXACT WIND DIRECTION AND ANY SUBTLE SNEAKY
BACKDOOR FRONTS WITH THE NWLY FLOW IN PLACE ALOFT...ESPECIALLY
THE MID COAST OF MAINE. IN ADDITION THERE COULD BE A FEW CLOUDS
AROUND ON WEDNESDAY AS PER LATEST ECMWF WITH SHORT WAVE TROUGH
MOVING THROUGH WEDNESDAY MORNING. HOWEVER...HIGHS IN THE 90S SEEMS
ACCEPTABLE FOR MOST AS THE PATTERN FAVORS IT WITH DOWNSLOPING
WINDS...850MB TEMPS AROUND +20C...AND 1000-500MB THICKNESS VALUES
BETWEEN 577 AND 580 DM.
AS FAR AS POPS GO FOR WEDNESDAY THROUGH FRIDAY...THERE/S A SLIGHT
CHANCE OF SHOWERS AND THUNDERSTORMS TUESDAY NIGHT INTO WEDNESDAY
MORNING AS A WEAK SHORT WAVE TROUGH MOVES THROUGH THE MEAN NWLY
FLOW ALOFT. OTHERWISE...THE BALANCE OF WEDNESDAY LOOKS DRY AS DOES
THURSDAY WITH RIDGING IN PLACE. CAN/T COMPLETELY RULE OUT A SPOT
THUNDERSTORM THURSDAY...ESPECIALLY IN THE MOUNTAINS...BUT A
SLIGHTLY BETTER CHANCE OF A SHOWER OR THUNDERSTORMS EXISTS ACROSS
NORTHERN AND WESTERN ZONES THURSDAY NIGHT WITH THE APPROACH OF A
COLD FRONT.
FRONT MOVES OFFSHORE DURING THE DAY ON FRIDAY...HOWEVER...IT
SHOULD STILL REMAIN VERY WARM. TEMPS MAY APPROACH 90 IN SOUTHERN
MAINE INTO SOUTHERN NH. DRY WEATHER EXPECTED THEN.
DRY AND COOLER WEATHER EXPECTED FRIDAY NIGHT THROUGH SATURDAY IN
THE CAA REGIME. MODEL CONSENSUS IS CURRENTLY QUITE GOOD ON
FORECASTING A COOL RAINMAKER FOR SUNDAY AND SUNDAY NIGHT...SO
INCREASED POPS A BIT THEN BUT IT/S STILL PRETTY FAR OUT AND
SUBJECT TO CHANGE.
&&
.AVIATION /13Z MONDAY THROUGH FRIDAY/...
SHORT TERM...AREAS OF IFR OR LIFR CONDS ARE EXPECTED EARLY THIS
MORNING IN STRATUS AND AREAS OF FOG BUT WILL IMPROVE TO VFR BY
THIS AFTERNOON. CONDS WILL ONCE AGAIN LOWER TO IFR OR LIFR
TONIGHT AS LOW CLOUDS AND FOG RETURN ALONG THE COASTAL PLAIN AND
THE ADJACENT INLAND AREAS AS WELL...WELL INLAND MVFR CONDS ARE
POSSIBLE IN AREAS OF STRATUS THAT WILL MOVE WELL INLAND. ON TUESDAY THE
LOW CLOUDS AND FOG WILL ONCE AGAIN BURN OFF BY AFTERNOON OVER MOST
AREAS WITH THE COASTAL LOCATIONS BEING THE LAST TO IMPROVE.
LONG TERM...SOME LOCAL IFR ON FOG AND STRATUS POSSIBLE TUESDAY
NIGHT...ESPECIALLY ALONG THE COAST. THEREAFTER...MAINLY VFR
CONDITIONS ARE EXPECTED WEDNESDAY THROUGH FRIDAY.
&&
.MARINE...
SHORT TERM...HIGH PRESSURE AND LIGHT WINDS WILL REMAIN OVER THE
WATERS THROUGH TUESDAY. WIDESPREAD FOG CAN BE EXPECTED OVER THE
OUTER WATERS AND AREAS OF FOG IN THE BAYS TODAY THROUGH TUESDAY
RESTRICTING VISIBILITIES.
LONG TERM...MARGINAL SCA SEAS POSSIBLE ON THE OCEAN TUESDAY NIGHT
INTO EARLY WEDNESDAY. OTHERWISE...SUB-SCA CONDITIONS EXPECTED
THROUGH FRIDAY.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...CEMPA
SHORT TERM...
LONG TERM...
AVIATION...
MARINE...
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
134 PM EDT MON JUN 18 2012
.SYNOPSIS...
ISSUED AT 506 AM EDT MON JUN 18 2012
WV IMAGERY AND RUC ANALYSIS INDICATED ZONAL MID/UPPER LEVEL FLOW
ACROSS THE NRN CONUS FROM THE PAC NW TO THE WRN GREAT LAKES WITH A
110-120 KT 250-300 MB JET THROUGH THE NRN PLAINS. AT THE SFC...A
COLD FRONT EXTENDED THROUGH THE ERN DAKOTAS INTO N CNTRL NEBRASKA
FROM LOW PRES NEAR WINNIPEG. A WARM FRONT STRETCHED FROM NW MN
THROUGH WRN WI INTO NRN IL. A LARGE MCS THAT DEVELOPED OVER NE SOUTH
DAKOTA HAS MOVED THROUGH CNTRL/SRN MN INTO WI AND UPPER MI. THE
STRONGEST CONVECTIVE ELEMENTS WITH THE BEST LOW LEVEL MOISTURE
INFLOW AND INSTABILITY AVAILABLE WERE LINED UP FROM E CNTRL THROUGH
SRN WI.
&&
.SHORT TERM...(TODAY)
ISSUED AT 506 AM EDT MON JUN 18 2012
SATELLITE AND RADAR TRENDS SUGGEST THAT THE MCS WILL MOVE THROUGH
THE CWA EARLY THIS MORNING...ENDING OVER CNTRL UPPER MI BY AROUND
10Z AND OVER THE EAST BY 12Z. HOWEVER...SOME SCT SHRA/TSRA MAY
REDEVELOP BY LATE MORNING AS A SHORTWAVE TROUGH MOVES QUICKLY TOWARD
THE AREA FROM THE NW MN. EVEN THROUGH THERE WAS EXTENSIVE CLOUD
COVER IN THE WAKE OF THE MCS...EXPECT THE MID AND HIGH CLOUDS TO
THIN OUT ENOUGH TO ALLOW MODERATE DAYTIME HEATING PUSHING TEMPS TO
AROUND 80 AND MLCAPE VALUES INTO THE 1K-2K J/KG RANGE THIS
AFTERNOON. AS THE NOSE OF THE JET STREAK AND THE SFC TROUGH PUSHES
INTO THE REGION EXPECT FORCING FOR TSTM DEVELOPMENT TO INCREASE.
ALTHOUGH THERE IS STILL CONSIDERABLE UNCERTAINTY WITH THE
TIMING/LOCATION OF CONVECTIVE DEVELOPMENT THIS AFTERNOON...THE
CONSENSUS OF HIGHER RES MODELS SUGGEST TSRA SHOULD RAPIDLY DEVELOP
THIS AFTERNOON OVER THE WEST...AIDED BY LAKE SUPERIOR BREEZE
BOUNDARY...AND SPREAD INTO CNTRL UPPER MI BY MID AFTERNOON BEFORE
SLIDING SOUTHEAST OF THE AREA EARLY THIS EVENING.
STRONG 500 MB WINDS(TO 80 KT) LEADING TO 0-6KM BULK SHEAR VALUES IN
THE 60-70 KT RANGE WILL LEAD TO POTENTIAL FOR SUPERCELLS BEFORE
CONVECTION BECOMES MORE ORGANIZED INTO LARGER CLUSTERS OR LINES.
GIVEN THE STRONG WIND FIELDS AND STEEP LOW LEVEL LAPSE RATES THIS
AFTERNOON...THE GREATEST SVR THREAT WOULD BE STRONG/DAMAGING
WINDS...PER SPC. AN ISOLATED TORNADO CANNOT BE RULED OUT WITH ANY
SUPERCELLS THAT DEVELOP...ESPECIALLY NEAR THE WARM FRONTAL BOUNDARY
EXPECTED NEAR THE WI BORDER.
.LONG TERM...(TONIGHT THROUGH SUNDAY)
ISSUED AT 506 AM EDT MON JUN 18 2012
TUESDAY...
WE WILL START THIS PERIOD WITH W-SW FLOW ALOFT...IN
BETWEEN A DOMINANT RIDGE OF HIGH PRESSURE OVER THE TN/OH RIVER
VALLEYS AND A PROGRESSIVE LOW OVER MT. AT THE SFC...THE EXITING LOW
SHOULD BE JUST NE OF JAMES BAY...WITH A COLD FRONT EXTENDING
SOUTHWARD ACROSS W LAKE SUPERIOR /OR JUST NW OF LAKE SUPERIOR/
THROUGH THE NEXT LOW SET UP OVER S CENTRAL SD. EXPECT WARMER AIR TO
SURGE INTO THE S AND E SECTIONS OF THE CWA DURING THE LATE AFTERNOON
HOURS TUESDAY...AS THE MAIN WARM FRONT PUSHES N OF LAKE MI TO OR
ACROSS PORTIONS OF LAKE SUPERIOR 00Z WEDNESDAY /850MB TEMPS OF
18-22C/. EXPECT SHOWERS AND TS TO SLIDE IN DURING THE AFTERNOON
HOURS...MOST LIKELY OVER LAKE SUPERIOR AND FAR W UPPER MI.
TUESDAY NIGHT AND WEDNESDAY...
THE MT LOW WILL SHIFT ACROSS S MANITOBA BY DAYBREAK
WEDNESDAY...BEFORE PUSHING INTO N CENTRAL ONTARIO. MODELS LOOK TO BE
FOLLOWING 3 SEPARATE IDEAS WITH THE TRACK OF THIS LOW...WITH THE
FIRST BEING A MORE PROGRESSIVE GFS/NAM/SREF SOLUTION. THE OLDER
17/12Z RUNS OF THE CANADIAN AND ECMWF...WHILE FAIRLY CONSISTENT WITH
THE OTHER MODELS THROUGH TUESDAY AFTERNOON...BECOME A BIT SLOWER
DURING THE AFTERNOON HOURS...WITH THE CANADIAN NEVER REALLY CATCHING
UP UNTIL LATER IN THE WORK WEEK. AS A RESULT...THE CANADIAN WILL NOT
BE HIGHLY UTILIZED BEYOND TUESDAY NIGHT. BACK AT THE
SFC...TEMPERATURES MAY STRUGGLE TO GET MUCH BELOW 70F TUESDAY NIGHT
AS THE WARM FRONT SURGES WELL NORTH OF LAKE SUPERIOR BY DAYBREAK
WEDNESDAY /35-40KT 850MB WINDS AND TEMPS OF 15-20C/...IN RESPONSE TO
THE LOW SHIFTING ACROSS W LAKE SUPERIOR/MN TUESDAY NIGHT...AND NW OF
LAKE SUPERIOR BY 12Z WEDNESDAY. AS A RESULT OF BEING ONE OF THE
DEEPER SOLUTIONS...THE SFC LOW IS ON THE NW OR SLOWER SIDE. THIS
DOES MAKE TIMING THE PASSAGE OF THE COLD FRONT A BIT MORE
DIFFICULT...WITH IT LIKELY SET UP ACROSS THE WESTERN THIRD OF THE
CWA BY 18Z WEDNESDAY.
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...
EXPECT THE COLD FRONT TO CONTINUE ITS EASTWARD PROGRESSION AND BE
MAINLY E OF THE CWA BY 06Z THURSDAY...WITH A WEAKER SECONDARY SFC
TROUGH ATTEMPTING TO CROSS WEDNESDAY NIGHT. MUCH OF OUR WEATHER WILL
BE DOMINATED BY THE LINGERING 500MB LOW SPINNING OVER HUDSON
BAY/ONTARIO/QUEBEC...WITH A TROUGH EXTENDING ACROSS THE GREAT LAKES
REGION. THE RESULT WITH BE COOLER W-NW FLOW...WITH 850MB TEMPS
AVERAGING 8-10C THURSDAY THROUGH EARLY FRIDAY. WITH HIGH PRESSURE AT
THE SFC...EXPECT DRY WEATHER THURSDAY THROUGH AT LEAST THURSDAY
NIGHT. LOWERED DEWPOINTS SLIGHTLY FROM CONSENSUS FOR WEDNESDAY NIGHT
INTO THURSDAY...WITH GOOD MIXING INTO PLENTY OF DRY AIR AOA 800MB
THURSDAY AFTERNOON. THIS RESULTED IN RH VALUES NEAR 35 PERCENT
INTERIOR WEST. WOULD NOT BE SURPRISED TO SEE LESS THAN 30 PERCENT AS
THE TIME NEARS.
FRIDAY THROUGH MONDAY...
THE 500MB RIDGE OVER THE S STATES WILL EXTEND UP THROUGH MT FRIDAY
MORNING...WITH THE LOW TO OUR NORTH SLOWLY EXITING. THERE ARE
SIGNIFICANT ENOUGH DIFFERENCES IN THE PATTERN BY SATURDAY AFTERNOON
TO RESULT IN A MODERATE TO LOWER CONFIDENCE FORECAST BEYOND THEN.
THE CONSENSUS IS TO BRING THE 500MB RIDGE UP THROUGH THE PLAINS
STATES THROUGH S CENTRAL CANADA BY MONDAY. EXPECT MODERATING
TEMPS...AND THE RETURN OF SLIGHT CHANCE/CHANCE POPS AS LOW PRESSURE
OVER SD/NE SATURDAY ATTEMPTS TO EXTEND A WARM FRONT ACROSS THE AREA
AS 500MB WAVE PUSHES IN. WHILE BOTH THE GFS AND ECMWF DO PRINT OUT
PRECIP SATURDAY NIGHT...IT IS MAINLY ALONG THE WI BORDER...AND
CONFIDENCE REMAINS LOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 133 PM EDT MON JUN 18 2012
SCT SHRA/TSRA WILL BE NEAR ENOUGH TO THE TAF SITES TO INCLUDE
THROUGH THIS AFTERNOON. VFR CONDITIONS EXPECTED TO CONTINUE THROUGH
THE PERIOD. MORE -SHRA COME THROUGH TUE WITH RETURN FLOW SETTING UP
LATE IN THE MORNING AND WENT PROB30 POPS AT ALL SITES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 506 AM EDT MON JUN 18 2012
RELATIVELY SMALL SECTIONS OF PATCHY TO AREAS OF FOG WILL REMAIN
POSSIBLE THROUGH WEDNESDAY AS ADDITIONAL MOISTURE PUSHES ACROSS THE
COOLER LS WATERS. LOW PRESSURE STRETCHING FROM S MANITOBA THROUGH NE
WILL CONSOLIDATE N-NW OF LS BY THIS EVENING BEFORE CROSSING JAMES
BAY AND INTO QUEBEC BY DAYBREAK TUESDAY. SOME THUNDERSTORMS COULD BE
STRONG THIS AFTERNOON EVENING...WITH STRONG WINDS AND LARGE HAIL
POSSIBLE /MAINLY ACROSS S PORTIONS OF LS/. A TROUGH OF LOW PRESSURE
WILL SET UP ACROSS LS...WHERE IT WILL REMAIN AS ANOTHER LOW DEVELOPS
OVER SD/NE TUESDAY MORNING. THIS SECONDARY LOW SHOULD CROSS N MN/W
LS TUESDAY NIGHT INTO WEDNESDAY MORNING...BEFORE SHIFTING ACROSS
CENTRAL ONTARIO AND DRAGGING A TROUGH/COLD FRONT OVER LS WEDNESDAY
AFTERNOON/EVENING. HIGH PRESSURE WILL THEN TAKE HOLD FOR WEDNESDAY
NIGHT...SHIFTING TO THE LOWER GREAT LAKES FRIDAY NIGHT AS ANOTHER
LOW DEVELOPS ACROSS THE CENTRAL TO NORTHERN PLAINS STATES. THIS LOW
SHOULD REMAIN TO OUR SOUTH...WITH AN ADDITIONAL HIGH SINKING ACROSS
THE UPPER GREAT LAKES FROM CENTRAL CANADA SATURDAY NIGHT THROUGH
MONDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...KF
AVIATION...07
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
743 AM EDT MON JUN 18 2012
.SYNOPSIS...
ISSUED AT 506 AM EDT MON JUN 18 2012
WV IMAGERY AND RUC ANALYSIS INDICATED ZONAL MID/UPPER LEVEL FLOW
ACROSS THE NRN CONUS FROM THE PAC NW TO THE WRN GREAT LAKES WITH A
110-120 KT 250-300 MB JET THROUGH THE NRN PLAINS. AT THE SFC...A
COLD FRONT EXTENDED THROUGH THE ERN DAKOTAS INTO N CNTRL NEBRASKA
FROM LOW PRES NEAR WINNIPEG. A WARM FRONT STRETCHED FROM NW MN
THROUGH WRN WI INTO NRN IL. A LARGE MCS THAT DEVELOPED OVER NE SOUTH
DAKOTA HAS MOVED THROUGH CNTRL/SRN MN INTO WI AND UPPER MI. THE
STRONGEST CONVECTIVE ELEMENTS WITH THE BEST LOW LEVEL MOISTURE
INFLOW AND INSTABILITY AVAILABLE WERE LINED UP FROM E CNTRL THROUGH
SRN WI.
&&
.SHORT TERM...(TODAY)
ISSUED AT 506 AM EDT MON JUN 18 2012
SATELLITE AND RADAR TRENDS SUGGEST THAT THE MCS WILL MOVE THROUGH
THE CWA EARLY THIS MORNING...ENDING OVER CNTRL UPPER MI BY AROUND
10Z AND OVER THE EAST BY 12Z. HOWEVER...SOME SCT SHRA/TSRA MAY
REDEVELOP BY LATE MORNING AS A SHORTWAVE TROUGH MOVES QUICKLY TOWARD
THE AREA FROM THE NW MN. EVEN THROUGH THERE WAS EXTENSIVE CLOUD
COVER IN THE WAKE OF THE MCS...EXPECT THE MID AND HIGH CLOUDS TO
THIN OUT ENOUGH TO ALLOW MODERATE DAYTIME HEATING PUSHING TEMPS TO
AROUND 80 AND MLCAPE VALUES INTO THE 1K-2K J/KG RANGE THIS
AFTERNOON. AS THE NOSE OF THE JET STREAK AND THE SFC TROUGH PUSHES
INTO THE REGION EXPECT FORCING FOR TSTM DEVELOPMENT TO INCREASE.
ALTHOUGH THERE IS STILL CONSIDERABLE UNCERTAINTY WITH THE
TIMING/LOCATION OF CONVECTIVE DEVELOPMENT THIS AFTERNOON...THE
CONSENSUS OF HIGHER RES MODELS SUGGEST TSRA SHOULD RAPIDLY DEVELOP
THIS AFTERNOON OVER THE WEST...AIDED BY LAKE SUPERIOR BREEZE
BOUNDARY...AND SPREAD INTO CNTRL UPPER MI BY MID AFTERNOON BEFORE
SLIDING SOUTHEAST OF THE AREA EARLY THIS EVENING.
STRONG 500 MB WINDS(TO 80 KT) LEADING TO 0-6KM BULK SHEAR VALUES IN
THE 60-70 KT RANGE WILL LEAD TO POTENTIAL FOR SUPERCELLS BEFORE
CONVECTION BECOMES MORE ORGANIZED INTO LARGER CLUSTERS OR LINES.
GIVEN THE STRONG WIND FIELDS AND STEEP LOW LEVEL LAPSE RATES THIS
AFTERNOON...THE GREATEST SVR THREAT WOULD BE STRONG/DAMAGING
WINDS...PER SPC. AN ISOLATED TORNADO CANNOT BE RULED OUT WITH ANY
SUPERCELLS THAT DEVELOP...ESPECIALLY NEAR THE WARM FRONTAL BOUNDARY
EXPECTED NEAR THE WI BORDER.
.LONG TERM...(TONIGHT THROUGH SUNDAY)
ISSUED AT 506 AM EDT MON JUN 18 2012
TUESDAY...
WE WILL START THIS PERIOD WITH W-SW FLOW ALOFT...IN
BETWEEN A DOMINANT RIDGE OF HIGH PRESSURE OVER THE TN/OH RIVER
VALLEYS AND A PROGRESSIVE LOW OVER MT. AT THE SFC...THE EXITING LOW
SHOULD BE JUST NE OF JAMES BAY...WITH A COLD FRONT EXTENDING
SOUTHWARD ACROSS W LAKE SUPERIOR /OR JUST NW OF LAKE SUPERIOR/
THROUGH THE NEXT LOW SET UP OVER S CENTRAL SD. EXPECT WARMER AIR TO
SURGE INTO THE S AND E SECTIONS OF THE CWA DURING THE LATE AFTERNOON
HOURS TUESDAY...AS THE MAIN WARM FRONT PUSHES N OF LAKE MI TO OR
ACROSS PORTIONS OF LAKE SUPERIOR 00Z WEDNESDAY /850MB TEMPS OF
18-22C/. EXPECT SHOWERS AND TS TO SLIDE IN DURING THE AFTERNOON
HOURS...MOST LIKELY OVER LAKE SUPERIOR AND FAR W UPPER MI.
TUESDAY NIGHT AND WEDNESDAY...
THE MT LOW WILL SHIFT ACROSS S MANITOBA BY DAYBREAK
WEDNESDAY...BEFORE PUSHING INTO N CENTRAL ONTARIO. MODELS LOOK TO BE
FOLLOWING 3 SEPARATE IDEAS WITH THE TRACK OF THIS LOW...WITH THE
FIRST BEING A MORE PROGRESSIVE GFS/NAM/SREF SOLUTION. THE OLDER
17/12Z RUNS OF THE CANADIAN AND ECMWF...WHILE FAIRLY CONSISTENT WITH
THE OTHER MODELS THROUGH TUESDAY AFTERNOON...BECOME A BIT SLOWER
DURING THE AFTERNOON HOURS...WITH THE CANADIAN NEVER REALLY CATCHING
UP UNTIL LATER IN THE WORK WEEK. AS A RESULT...THE CANADIAN WILL NOT
BE HIGHLY UTILIZED BEYOND TUESDAY NIGHT. BACK AT THE
SFC...TEMPERATURES MAY STRUGGLE TO GET MUCH BELOW 70F TUESDAY NIGHT
AS THE WARM FRONT SURGES WELL NORTH OF LAKE SUPERIOR BY DAYBREAK
WEDNESDAY /35-40KT 850MB WINDS AND TEMPS OF 15-20C/...IN RESPONSE TO
THE LOW SHIFTING ACROSS W LAKE SUPERIOR/MN TUESDAY NIGHT...AND NW OF
LAKE SUPERIOR BY 12Z WEDNESDAY. AS A RESULT OF BEING ONE OF THE
DEEPER SOLUTIONS...THE SFC LOW IS ON THE NW OR SLOWER SIDE. THIS
DOES MAKE TIMING THE PASSAGE OF THE COLD FRONT A BIT MORE
DIFFICULT...WITH IT LIKELY SET UP ACROSS THE WESTERN THIRD OF THE
CWA BY 18Z WEDNESDAY.
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...
EXPECT THE COLD FRONT TO CONTINUE ITS EASTWARD PROGRESSION AND BE
MAINLY E OF THE CWA BY 06Z THURSDAY...WITH A WEAKER SECONDARY SFC
TROUGH ATTEMPTING TO CROSS WEDNESDAY NIGHT. MUCH OF OUR WEATHER WILL
BE DOMINATED BY THE LINGERING 500MB LOW SPINNING OVER HUDSON
BAY/ONTARIO/QUEBEC...WITH A TROUGH EXTENDING ACROSS THE GREAT LAKES
REGION. THE RESULT WITH BE COOLER W-NW FLOW...WITH 850MB TEMPS
AVERAGING 8-10C THURSDAY THROUGH EARLY FRIDAY. WITH HIGH PRESSURE AT
THE SFC...EXPECT DRY WEATHER THURSDAY THROUGH AT LEAST THURSDAY
NIGHT. LOWERED DEWPOINTS SLIGHTLY FROM CONSENSUS FOR WEDNESDAY NIGHT
INTO THURSDAY...WITH GOOD MIXING INTO PLENTY OF DRY AIR AOA 800MB
THURSDAY AFTERNOON. THIS RESULTED IN RH VALUES NEAR 35 PERCENT
INTERIOR WEST. WOULD NOT BE SURPRISED TO SEE LESS THAN 30 PERCENT AS
THE TIME NEARS.
FRIDAY THROUGH MONDAY...
THE 500MB RIDGE OVER THE S STATES WILL EXTEND UP THROUGH MT FRIDAY
MORNING...WITH THE LOW TO OUR NORTH SLOWLY EXITING. THERE ARE
SIGNIFICANT ENOUGH DIFFERENCES IN THE PATTERN BY SATURDAY AFTERNOON
TO RESULT IN A MODERATE TO LOWER CONFIDENCE FORECAST BEYOND THEN.
THE CONSENSUS IS TO BRING THE 500MB RIDGE UP THROUGH THE PLAINS
STATES THROUGH S CENTRAL CANADA BY MONDAY. EXPECT MODERATING
TEMPS...AND THE RETURN OF SLIGHT CHANCE/CHANCE POPS AS LOW PRESSURE
OVER SD/NE SATURDAY ATTEMPTS TO EXTEND A WARM FRONT ACROSS THE AREA
AS 500MB WAVE PUSHES IN. WHILE BOTH THE GFS AND ECMWF DO PRINT OUT
PRECIP SATURDAY NIGHT...IT IS MAINLY ALONG THE WI BORDER...AND
CONFIDENCE REMAINS LOW.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 741 AM EDT MON JUN 18 2012
SCT SHRA/TSRA WILL BE NEAR TO KSAW ENOUGH TO INCLUDE VCTS THROUGH
14Z. AFTER THE HRA END...THERE MAY BE A PERIOD OF LO CLDS/MVFR
CONDITIONS IN ADVANCE OF WARM FRONT TRYING TO MOVE NE FM
WI...ESPECIALLY AT SAW WITH UPSLOPE S WIND. MORE SHRA/TS ARE PSBL IN
THE AFTN...BUT ONCE AGAIN DID NOT INCLUDE EXPLICIT TSRA DUE TO TIMING
DIFFERENCES AMONG NUMERICAL MODELS. VIGOROUS DRYING ALOFT SHOULD END
THE SHRA/TS THREAT W-E LATE THIS AFTN AND ENSURE VFR CONDITIONS FOR
THIS EVNG. &&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 506 AM EDT MON JUN 18 2012
RELATIVELY SMALL SECTIONS OF PATCHY TO AREAS OF FOG WILL REMAIN
POSSIBLE THROUGH WEDNESDAY AS ADDITIONAL MOISTURE PUSHES ACROSS THE
COOLER LS WATERS. LOW PRESSURE STRETCHING FROM S MANITOBA THROUGH NE
WILL CONSOLIDATE N-NW OF LS BY THIS EVENING BEFORE CROSSING JAMES
BAY AND INTO QUEBEC BY DAYBREAK TUESDAY. SOME THUNDERSTORMS COULD BE
STRONG THIS AFTERNOON EVENING...WITH STRONG WINDS AND LARGE HAIL
POSSIBLE /MAINLY ACROSS S PORTIONS OF LS/. A TROUGH OF LOW PRESSURE
WILL SET UP ACROSS LS...WHERE IT WILL REMAIN AS ANOTHER LOW DEVELOPS
OVER SD/NE TUESDAY MORNING. THIS SECONDARY LOW SHOULD CROSS N MN/W
LS TUESDAY NIGHT INTO WEDNESDAY MORNING...BEFORE SHIFTING ACROSS
CENTRAL ONTARIO AND DRAGGING A TROUGH/COLD FRONT OVER LS WEDNESDAY
AFTERNOON/EVENING. HIGH PRESSURE WILL THEN TAKE HOLD FOR WEDNESDAY
NIGHT...SHIFTING TO THE LOWER GREAT LAKES FRIDAY NIGHT AS ANOTHER
LOW DEVELOPS ACROSS THE CENTRAL TO NORTHERN PLAINS STATES. THIS LOW
SHOULD REMAIN TO OUR SOUTH...WITH AN ADDITIONAL HIGH SINKING ACROSS
THE UPPER GREAT LAKES FROM CENTRAL CANADA SATURDAY NIGHT THROUGH
MONDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...KF
AVIATION...JLB
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
506 AM EDT MON JUN 18 2012
.SYNOPSIS...
ISSUED AT 506 AM EDT MON JUN 18 2012
WV IMAGERY AND RUC ANALYSIS INDICATED ZONAL MID/UPPER LEVEL FLOW
ACROSS THE NRN CONUS FROM THE PAC NW TO THE WRN GREAT LAKES WITH A
110-120 KT 250-300 MB JET THROUGH THE NRN PLAINS. AT THE SFC...A
COLD FRONT EXTENDED THROUGH THE ERN DAKOTAS INTO N CNTRL NEBRASKA
FROM LOW PRES NEAR WINNIPEG. A WARM FRONT STRETCHED FROM NW MN
THROUGH WRN WI INTO NRN IL. A LARGE MCS THAT DEVELOPED OVER NE SOUTH
DAKOTA HAS MOVED THROUGH CNTRL/SRN MN INTO WI AND UPPER MI. THE
STRONGEST CONVECTIVE ELEMENTS WITH THE BEST LOW LEVEL MOISTURE
INFLOW AND INSTABILITY AVAILABLE WERE LINED UP FROM E CNTRL THROUGH
SRN WI.
&&
.SHORT TERM...(TODAY)
ISSUED AT 506 AM EDT MON JUN 18 2012
SATELLITE AND RADAR TRENDS SUGGEST THAT THE MCS WILL MOVE THROUGH
THE CWA EARLY THIS MORNING...ENDING OVER CNTRL UPPER MI BY AROUND
10Z AND OVER THE EAST BY 12Z. HOWEVER...SOME SCT SHRA/TSRA MAY
REDEVELOP BY LATE MORNING AS A SHORTWAVE TROUGH MOVES QUICKLY TOWARD
THE AREA FROM THE NW MN. EVEN THROUGH THERE WAS EXTENSIVE CLOUD
COVER IN THE WAKE OF THE MCS...EXPECT THE MID AND HIGH CLOUDS TO
THIN OUT ENOUGH TO ALLOW MODERATE DAYTIME HEATING PUSHING TEMPS TO
AROUND 80 AND MLCAPE VALUES INTO THE 1K-2K J/KG RANGE THIS
AFTERNOON. AS THE NOSE OF THE JET STREAK AND THE SFC TROUGH PUSHES
INTO THE REGION EXPECT FORCING FOR TSTM DEVELOPMENT TO INCREASE.
ALTHOUGH THERE IS STILL CONSIDERABLE UNCERTAINTY WITH THE
TIMING/LOCATION OF CONVECTIVE DEVELOPMENT THIS AFTERNOON...THE
CONSENSUS OF HIGHER RES MODELS SUGGEST TSRA SHOULD RAPIDLY DEVELOP
THIS AFTERNOON OVER THE WEST...AIDED BY LAKE SUPERIOR BREEZE
BOUNDARY...AND SPREAD INTO CNTRL UPPER MI BY MID AFTERNOON BEFORE
SLIDING SOUTHEAST OF THE AREA EARLY THIS EVENING.
STRONG 500 MB WINDS(TO 80 KT) LEADING TO 0-6KM BULK SHEAR VALUES IN
THE 60-70 KT RANGE WILL LEAD TO POTENTIAL FOR SUPERCELLS BEFORE
CONVECTION BECOMES MORE ORGANIZED INTO LARGER CLUSTERS OR LINES.
GIVEN THE STRONG WIND FIELDS AND STEEP LOW LEVEL LAPSE RATES THIS
AFTERNOON...THE GREATEST SVR THREAT WOULD BE STRONG/DAMAGING
WINDS...PER SPC. AN ISOLATED TORNADO CANNOT BE RULED OUT WITH ANY
SUPERCELLS THAT DEVELOP...ESPECIALLY NEAR THE WARM FRONTAL BOUNDARY
EXPECTED NEAR THE WI BORDER.
.LONG TERM...(TONIGHT THROUGH SUNDAY)
ISSUED AT 506 AM EDT MON JUN 18 2012
TUESDAY...
WE WILL START THIS PERIOD WITH W-SW FLOW ALOFT...IN
BETWEEN A DOMINANT RIDGE OF HIGH PRESSURE OVER THE TN/OH RIVER
VALLEYS AND A PROGRESSIVE LOW OVER MT. AT THE SFC...THE EXITING LOW
SHOULD BE JUST NE OF JAMES BAY...WITH A COLD FRONT EXTENDING
SOUTHWARD ACROSS W LAKE SUPERIOR /OR JUST NW OF LAKE SUPERIOR/
THROUGH THE NEXT LOW SET UP OVER S CENTRAL SD. EXPECT WARMER AIR TO
SURGE INTO THE S AND E SECTIONS OF THE CWA DURING THE LATE AFTERNOON
HOURS TUESDAY...AS THE MAIN WARM FRONT PUSHES N OF LAKE MI TO OR
ACROSS PORTIONS OF LAKE SUPERIOR 00Z WEDNESDAY /850MB TEMPS OF
18-22C/. EXPECT SHOWERS AND TS TO SLIDE IN DURING THE AFTERNOON
HOURS...MOST LIKELY OVER LAKE SUPERIOR AND FAR W UPPER MI.
TUESDAY NIGHT AND WEDNESDAY...
THE MT LOW WILL SHIFT ACROSS S MANITOBA BY DAYBREAK
WEDNESDAY...BEFORE PUSHING INTO N CENTRAL ONTARIO. MODELS LOOK TO BE
FOLLOWING 3 SEPARATE IDEAS WITH THE TRACK OF THIS LOW...WITH THE
FIRST BEING A MORE PROGRESSIVE GFS/NAM/SREF SOLUTION. THE OLDER
17/12Z RUNS OF THE CANADIAN AND ECMWF...WHILE FAIRLY CONSISTENT WITH
THE OTHER MODELS THROUGH TUESDAY AFTERNOON...BECOME A BIT SLOWER
DURING THE AFTERNOON HOURS...WITH THE CANADIAN NEVER REALLY CATCHING
UP UNTIL LATER IN THE WORK WEEK. AS A RESULT...THE CANADIAN WILL NOT
BE HIGHLY UTILIZED BEYOND TUESDAY NIGHT. BACK AT THE
SFC...TEMPERATURES MAY STRUGGLE TO GET MUCH BELOW 70F TUESDAY NIGHT
AS THE WARM FRONT SURGES WELL NORTH OF LAKE SUPERIOR BY DAYBREAK
WEDNESDAY /35-40KT 850MB WINDS AND TEMPS OF 15-20C/...IN RESPONSE TO
THE LOW SHIFTING ACROSS W LAKE SUPERIOR/MN TUESDAY NIGHT...AND NW OF
LAKE SUPERIOR BY 12Z WEDNESDAY. AS A RESULT OF BEING ONE OF THE
DEEPER SOLUTIONS...THE SFC LOW IS ON THE NW OR SLOWER SIDE. THIS
DOES MAKE TIMING THE PASSAGE OF THE COLD FRONT A BIT MORE
DIFFICULT...WITH IT LIKELY SET UP ACROSS THE WESTERN THIRD OF THE
CWA BY 18Z WEDNESDAY.
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...
EXPECT THE COLD FRONT TO CONTINUE ITS EASTWARD PROGRESSION AND BE
MAINLY E OF THE CWA BY 06Z THURSDAY...WITH A WEAKER SECONDARY SFC
TROUGH ATTEMPTING TO CROSS WEDNESDAY NIGHT. MUCH OF OUR WEATHER WILL
BE DOMINATED BY THE LINGERING 500MB LOW SPINNING OVER HUDSON
BAY/ONTARIO/QUEBEC...WITH A TROUGH EXTENDING ACROSS THE GREAT LAKES
REGION. THE RESULT WITH BE COOLER W-NW FLOW...WITH 850MB TEMPS
AVERAGING 8-10C THURSDAY THROUGH EARLY FRIDAY. WITH HIGH PRESSURE AT
THE SFC...EXPECT DRY WEATHER THURSDAY THROUGH AT LEAST THURSDAY
NIGHT. LOWERED DEWPOINTS SLIGHTLY FROM CONSENSUS FOR WEDNESDAY NIGHT
INTO THURSDAY...WITH GOOD MIXING INTO PLENTY OF DRY AIR AOA 800MB
THURSDAY AFTERNOON. THIS RESULTED IN RH VALUES NEAR 35 PERCENT
INTERIOR WEST. WOULD NOT BE SURPRISED TO SEE LESS THAN 30 PERCENT AS
THE TIME NEARS.
FRIDAY THROUGH MONDAY...
THE 500MB RIDGE OVER THE S STATES WILL EXTEND UP THROUGH MT FRIDAY
MORNING...WITH THE LOW TO OUR NORTH SLOWLY EXITING. THERE ARE
SIGNIFICANT ENOUGH DIFFERENCES IN THE PATTERN BY SATURDAY AFTERNOON
TO RESULT IN A MODERATE TO LOWER CONFIDENCE FORECAST BEYOND THEN.
THE CONSENSUS IS TO BRING THE 500MB RIDGE UP THROUGH THE PLAINS
STATES THROUGH S CENTRAL CANADA BY MONDAY. EXPECT MODERATING
TEMPS...AND THE RETURN OF SLIGHT CHANCE/CHANCE POPS AS LOW PRESSURE
OVER SD/NE SATURDAY ATTEMPTS TO EXTEND A WARM FRONT ACROSS THE AREA
AS 500MB WAVE PUSHES IN. WHILE BOTH THE GFS AND ECMWF DO PRINT OUT
PRECIP SATURDAY NIGHT...IT IS MAINLY ALONG THE WI BORDER...AND
CONFIDENCE REMAINS LOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 129 AM EDT MON JUN 18 2012
INCRSG SLY FLOW OF MOIST AIR BTWN HI PRES OVER NEW ENGLAND AND LO
PRES IN THE NRN PLAINS CAUSED AREA OF SHRA/TS TO DVLP OVER CNTRL MN
THIS EVNG. SINCE THE BULK OF THE SHRA/TS ARE HEADING MORE ESEWD INTO
WI...EXPECT THE SHRA/ISOLD TS MOVING TOWARD UPR MI TO REMAIN
RELATIVELY WEAK EVEN AS THE LLJ INCREASES IN MAGNITUDE AND CAUSES
LLWS. BEST CHC FOR TS/MVFR CONDITIONS WITH THE PCPN WL BE AT
IWD...AND INCLUDED MENTION OF TS AT IWD FOR THE FIRST HR OR SO OF
TAF PERIOD. FARTHER NE...RESIDUAL DRY LLVL AIR WL LIKELY MAINTAIN VFR
CONDITIONS WHEN THE -SHRA ARRIVE AT CMX/SAW. AFTER THE -SHRA
END...THERE MAY BE A PERIOD OF LO CLDS/MVFR CONDITIONS IN ADVANCE OF
WARM FRONT TRYING TO MOVE NE FM WI...ESPECIALLY AT SAW WITH UPSLOPE
S WIND. MORE SHRA/TS ARE PSBL IN THE AFTN...BUT ONCE AGAIN DID NOT
INCLUDE EXPLICIT MENTION OF TS DUE TO TIMING DIFFERENCES AMONG
NUMERICAL MODELS. VIGOROUS DRYING ALOFT SHOULD END THE SHRA/TS
THREAT W-E LATE THIS AFTN AND ENSURE VFR CONDITIONS FOR THIS EVNG.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 506 AM EDT MON JUN 18 2012
RELATIVELY SMALL SECTIONS OF PATCHY TO AREAS OF FOG WILL REMAIN
POSSIBLE THROUGH WEDNESDAY AS ADDITIONAL MOISTURE PUSHES ACROSS THE
COOLER LS WATERS. LOW PRESSURE STRETCHING FROM S MANITOBA THROUGH NE
WILL CONSOLIDATE N-NW OF LS BY THIS EVENING BEFORE CROSSING JAMES
BAY AND INTO QUEBEC BY DAYBREAK TUESDAY. SOME THUNDERSTORMS COULD BE
STRONG THIS AFTERNOON EVENING...WITH STRONG WINDS AND LARGE HAIL
POSSIBLE /MAINLY ACROSS S PORTIONS OF LS/. A TROUGH OF LOW PRESSURE
WILL SET UP ACROSS LS...WHERE IT WILL REMAIN AS ANOTHER LOW DEVELOPS
OVER SD/NE TUESDAY MORNING. THIS SECONDARY LOW SHOULD CROSS N MN/W
LS TUESDAY NIGHT INTO WEDNESDAY MORNING...BEFORE SHIFTING ACROSS
CENTRAL ONTARIO AND DRAGGING A TROUGH/COLD FRONT OVER LS WEDNESDAY
AFTERNOON/EVENING. HIGH PRESSURE WILL THEN TAKE HOLD FOR WEDNESDAY
NIGHT...SHIFTING TO THE LOWER GREAT LAKES FRIDAY NIGHT AS ANOTHER
LOW DEVELOPS ACROSS THE CENTRAL TO NORTHERN PLAINS STATES. THIS LOW
SHOULD REMAIN TO OUR SOUTH...WITH AN ADDITIONAL HIGH SINKING ACROSS
THE UPPER GREAT LAKES FROM CENTRAL CANADA SATURDAY NIGHT THROUGH
MONDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...KF
AVIATION...KC
MARINE...KF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1205 AM CDT MON JUN 18 2012
.UPDATED FOR 06Z AVIATION DISCUSSION BELOW...
.DISCUSSION...
TO SAY THE NEXT FEW DAYS WILL BE ACTIVE IS AN UNDERSTATEMENT WITH
SEVERAL ROUNDS OF THUNDERSTORMS/SEVERE WEATHER EXPECTED...ALONG WITH
A RISK FOR MORE FLASH FLOODING. STILL ANTICIPATING A SEVERE WEATHER
EPISODE THIS AFTERNOON INTO TONIGHT. LOOKING LIKE WE GET A BREAK IN
THE ACTION DURING THE DAY MONDAY...BEFORE A WARM FRONT COMES SURGING
BACK NORTH MONDAY NIGHT. THIS FRONT WILL BE ANCHORED OVER THE AREA
TUESDAY THOUGH WEDNESDAY...WITH MULTIPLE ROUNDS OF THUNDERSTORMS
EXPECTED OVER THOSE TWO DAYS. BESIDE SEVERE WEATHER
TUESDAY/WEDNESDAY...FLOW WILL BE NEARLY PARALLEL TO THE FRONT...WITH
THREAT FOR TRAINING THUNDERSTORMS AND FLASH FLOODING EXISTING THOSE
DAYS.
WATER VAPOR IMAGERY ALONG WITH RAP ANALYSIS SHOWS A VERY STRONG
UPPER JET /100-150 KTS/ SLAMMING ACROSS THE NORTHERN ROCKIES AND
INTO THE NORTHERN PLAINS RIGHT NOW. BATCH OF SHOWERS CONTINUES TO
WORK EAST ACROSS MN INTO WI THIS AFTERNOON ON NOSE OF 40 KT LLJ
AND LEADING BLAST OF THETA-E ADVECTION. BACK FURTHER
WEST...STARTING TO SEE A NICE WARM FRONT TAKE SHAPE BEHIND THE
CLOUDS IN SW MN INTO NE SD...ALMOST RIGHT ALONG THE BUFFALO RIDGE.
MLCAPES SOUTH OF THE BOUNDARY IN ERN SODAK HAVE INCREASED TO
AROUND 3000 J/KG. INCREASING WINDS ALOFT AND BACKING WINDS NORTH
OF THE BOUNDARY HAVE RESULTED IN BOTH DEEP LAYER SHEAR /NOW AROUND
50 KTS/ AND 0-1KM SHEAR /25-30 KTS ALONG THE WARM FRONT/
INCREASING QUITE A BIT THIS AFTERNOON. HI-RES GUIDANCE ALL
SIMILAR WITH INITIATING CONVECTION BY 22Z ALONG THE SD/MN BORDER
AROUND YELLOW MEDICINE/LAC QUI PARLE COUNTIES. GIVEN SHEAR AND
INSTABILITY PROFILES...STORM TYPE WILL BE SUPER CELLULAR WITH A
GOOD RISK OF VERY LARGE HAIL...DAMAGING WINDS...AND TORNADOES
THROUGH ABOUT 0/1Z. WHAT IS MORE WORRISOME IS WHAT HAPPENS AFTER
THESE STORMS INITIATE. IT DOES NOT MATTER WHAT HI-RES GUIDANCE YOU
LOOK AT...HRRR/NMM/ARW/MPX-WRF...THEY ALL CONGEAL THE STORMS OVER
CENTRAL MINNESOTA INTO A LINE AND SEND IT RACING EAST ACROSS THE
AREA TONIGHT. BIG WORRY HERE IS THAT PARAMETERS APPEAR TO BE
COMING TOGETHER FOR THE FORMATION OF A SIGNIFICANT DERECHO THIS
EVENING THAT THEN ROUGHLY FOLLOWS I-94 DOWN INTO THE TWIN CITES.
BY 6Z...THE RAP HAS MUCAPE OVER THE TWIN CITIES OF AROUND 2500
J/KG...DCAPE OF AROUND 1000 J/KG...AND MOST WORRISOME OF ALL...AN
H85 LLJ INCREASING TO BETWEEN 65 AND 70 KTS ALL POINT TO THE
POTENTIAL FOR A SIGNIFICANT DERECHO. THE BIG HOPE IS THAT
SIGNIFICANTLY RAIN COOLED AIR /TEMPS IN RAIN HAVE FALLEN INTO THE
LOW AND MID 60S/ WILL STABILIZE THE BOUNDARY LAYER ENOUGH ACROSS
ERN MN THAT BOUNDARY LAYER CAN NOT RECOVER ENOUGH TO ALLOW WINDS
TO REACH THE SFC AND WE END UP WITH AN ELEVATED MCS. EITHER WAY
YOU SLICE IT...LOOKS LIKE IT WILL BE A LONG NIGHT FOR THE MPX
AREA.
TONIGHT...MODELS DRIVE A FRONT EAST OF THE AREA...WITH MONDAY NOW
LOOKING DRY DURING THE DAY AND CUT POPS OUT OF ALL BUT THE FAR SE
CWA. LATE MONDAY NIGHT...THE WARM FRONT COMES SURGING BACK
NORTH...WITH MODELS SHOWING ANOTHER ROUND OF THUNDERSTORMS COMING
INTO WRN AND CENTRAL MN MAINLY AFTER 06Z TUESDAY ON YET ANOTHER 50 KT
LLJ. THIS THEN LEADS US INTO WHAT IS LOOKING LIKE THE MOST ACTIVE
WEATHER PERIOD IN THE COMING DAYS FOR TUESDAY THROUGH WEDNESDAY.
GOOD NEWS HERE IS MODELS ARE NOW SHOWING BETTER AGREEMENT WITH
EACH OTHER THESE TWO DAYS...WITH THE ECMWF NOW BEING LESS
PROGRESSIVE AND SHOWING FRONTAL PLACEMENT MUCH MORE SIMILAR TO
WHAT THE GFS HAS BEEN SHOWING THE PAST COUPLE OF DAYS. WILL BE
VERY WARM AND HUMID SOUTH OF THE BOUNDARY...WITH A VERY UNSTABLE
AIRMASS LIKELY IN PLACE BOTH DAYS. DURING THE DAY TUESDAY...MAY NOT
SEE MUCH ACTIVITY AS STRONG CAPPING INVERSION...WITH H7 TEMPS
INCREASING TO AROUND +14C...BUT TUESDAY NIGHT...MODELS SHOW MID
LEVEL TEMPS COOLING...WITH ALL SORTS OF CONVECTION TAKING OFF.
WORRY BOTH TUESDAY AND WEDNESDAY IS THAT BESIDE ALL THE
INSTABILITY...AN IMPRESSIVE 70-90 KT SW MID-LEVEL JET WILL BE
SPLAYED OUT ACROSS CENTRAL MN...WITH PLENTY OF SHEAR PRESENT FOR
ORGANIZED/SEVERE CONVECTION. IN ADDITION...UPPER FLOW WILL BE NEARLY
PARALLEL TO THE FRONT TUES/WED...WHICH MEANS POTENTIAL FOR
TRAINING STORMS WILL BE HIGH...AND WITH PWATS UP AROUND 2 INCHES
/180 PERCENT OF NORMAL/...FLASH FLOODING WILL AGAIN BE A CONCERN.
MODELS FINALLY SHOWING WNW FLOW DEVELOPING ALOFT BY
THURSDAY...WITH THE MOISTURE AND ASSOCIATED RAIN FINALLY GETTING
KICKED OUT OF HERE. FOLLOWED THE ECMWF FOR THU/FRI...WHICH IS
DRY...BUT THE GFS DOES SHOW ANOTHER WAVE MOVING ACROSS THE AREA
THU NIGHT/FRI...JUST AS THE ECWMF SLIDES A 1020 MB HIGH ACROSS THE
AREA. BETTER AGREEMENT FOR THUNDERSTORMS SHOWS UP SATURDAY WHEN
THE ECWMF/GFS SHOW A STRONG WARM FRONT MOVING UP INTO THE MPX AREA
AS A SFC LOW WORKS ACROSS SODAK INTO IA. AS A RESULT...BROUGHT
CHANCE POPS BACK FRIDAY NIGHT THOUGH SAT NIGHT. LOOKING JUST
BEYOND THE FORECAST...THE GFS/ECMWF SHOW AN UPPER RIDGE BUILDING
IN ACROSS THE CENTRAL CONUS FOR THE LAST WEEK OF JUNE...WITH
SIGNS OF A DECENT HEAT WAVE SHOWING UP FOR THE END OF JUNE.
&&
.AVIATION... /06Z TAF ISSUANCE/
STILL HAVE STRONG/SEVERE CONVECTION MOVING ACROSS MAINLY SOUTHERN
PORTION OF THE CWA. WILL HOLD ONTO TSRA OVER EASTERN TAF SITES FOR
A FEW HOURS YET. THEN MAY HAVE SOME MVFR CIG/BR THROUGH ABOUT
13Z...AGAIN OVER EASTERN AREAS BEFORE WINDS DO SHIFT MORE
SOUTHWEST/WEST. SOME MID/HIGH LEVEL CLOUDS SPREADING EAST OVER
NORTHERN CWA WITH SOME CUMULUS OVER EASTERN AREAS AHEAD OF FRONT
THAT MOVES THROUGH THE REGION DURING THE DAY. MAY SEE WINDS GUST A
BIT LATER IN THE AFTERNOON OVER WESTERN AREA AFTER 18Z AS DRIER AIR
TRIES TO MOVE IN. WILL LIKELY SEE SOME CLOUDS DEVELOP AGAIN LATER IN
THE NIGHT/AFTER 06Z AHEAD OF WAA PATTERN. WILL HOLD OFF ON ANY
PRECIPITATION FOR NOW.
.KMSP...STILL HAVE SOME TSRA LAGGING THE MAIN LINE OF STORMS. WILL
HOLD ONTO THEM FOR ANOTHER COUPLE HOURS...AS IT SHOULD MOVE SOUTH
AND EAST. SOME CUMULUS AND MID CLOUDS EXPECTED INTO THE DAY MONDAY
AS FRONT MOVES ACROSS THE REGION. ANY REDEVELOPMENT DURING THE DAY
SHOULD REMAIN EAST OF THE AREA. SOUTHERLY WIND PERHAPS A BIT GUSTY
EARLY...SHOULD BECOME MORE WEST WITH FROPA ON MONDAY AFTERNOON.
WILL BRING MORE CLOUDS IN AFTER 06Z TUE AND PERHAPS SOME MID CLOUDS
OUT AHEAD OF NEXT WAA PATTERN WILL KEEP IT DRY THROUGH THEN.
OUTLOOK...
TUESDAY...VFR/MVFR WITH TSRA POSSIBLE. SE TO S WINDS 20 TO 25 KTS.
WEDNESDAY...VFR/MVFR WITH TSRA POSSIBLE. WINDS NW AT 12 TO 17
KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
MPG/DE
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1146 PM CDT SUN JUN 17 2012
.AVIATION...06Z TAF. VFR CONDITIONS ARE EXPECTED THROUGH THE TAF
PERIOD. CONDITIONS WILL REMAIN DRY AND CLOUDS WILL BE LIMITED TO
HIGH LEVELS. WINDS WILL BE GUSTY FROM A SOUTHERLY DIRECTION WITH
GUSTS OF 25 TO 30KTS POSSIBLE. WIND SPEEDS WILL DIMINISH SOME ON
MONDAY AS A SURFACE BOUNDARY EDGES TOWARD THE TERMINAL. THERE IS
JUST AN OUTSIDE CHANCE THAT A STORM MAY DEVELOP NW OF KGRI IN THE
VCNTY OF THE FRONT BUT IT APPEARS UNLIKELY ATTM THAT ACTIVITY WILL
REACH KGRI.
&&
PREV DISCUSSION... /ISSUED 400 PM CDT SUN JUN 17 2012/
SHORT TERM...THROUGH MONDAY AFTERNOON. PRIMARY CONCERN IS HOW
CLOSE PARTS OF THE SOUTHERN CWA WILL COME TO MEETING HEAT ADVISORY
CRITERIA ON MONDAY AFTERNOON...WITH NO SHOWERS/THUNDERSTORMS
FORECAST THROUGH THE NEXT 24 HOURS.
19Z OBJECTIVE SURFACE ANALYSIS REVEALED A STILL-DEEPENING 996MB LOW
OVER CENTRAL SD...IN RESPONSE TO A 110KT 300MB JET STREAK TRACKING
DUE EAST OUT OF MT INTO THE WESTERN DAKOTAS. A TROUGH AXIS
EXTENDED SOUTHWEST FROM THIS LOW INTO NORTHWEST NEB...BUT STILL
WELL NORTHWEST OF THE CWA. IN RESPONSE TO THE PRESSURE
FALLS...AND WITH MIXING TO AROUND THE 750MB ACROSS MOST OF THE CWA
PER FORECAST SOUNDINGS...A BREEZY/WINDY DAY HAS ENSUED...WITH
SUSTAINED SOUTHERLY SPEEDS BETWEEN 20-25 MPH/GUSTS TO AROUND 30
MPH AND LOCALLY HIGHER. AS SUSPECTED IN THE EARLIER AFTERNOON
DISCUSSION...DEWPOINTS HAVE STARTED TO DROP SEVERAL DEGREES ACROSS
THE CWA FROM WEST TO EAST THIS AFTERNOON IN RESPONSE TO THE DEEP
MIXING. IN FACT...WITH DEWPOINTS ALL THE WAY DOWN INTO THE UPPER
40S/LOW 50S IN SOME SOUTHWEST COUNTIES...RED FLAG WARNING CRITERIA
OF 20 PERCENT IS BEING BREACHED IN A FEW SPOTS...BUT WITH ONLY KS
COUNTIES OFFICIALLY HAVING A FAVORABLE FUEL STATUS FOR LARGE FIRE
GROWTH...AND ANY RELATIVE HUMIDITY VALUES BELOW 20 PERCENT LIKELY
TO ONLY AFFECT A SMALL AREA FOR 3 HOURS OR MORE...WILL NOT BE
ISSUING ANY FIRE HEADLINES. TEMP WISE...ALTHOUGH PARTS OF MAINLY
THE NORTHEAST HALF OF THE CWA COULD FALL SHORT OF FORECAST HIGHS
BY A FEW DEGREES...STILL SHOULD END UP WITH SOLID COVERAGE OF AT
LEAST LOW-MID 90S ACROSS MOST NEB COUNTIES...AND UPPER 90S IN MOST
OF KS ALONG WITH FURNAS COUNTY AREA. ALOFT...THE AFOREMENTIONED
JET STREAK AND ASSOCIATED MID LEVEL SHORTWAVE TRANSLATING ACROSS
THE NORTHERN PLAINS/SOUTHERN CANADA REGION IS BY FAR THE MAIN
FEATURE OF INTEREST...WITH WEAKER QUASI-ZONAL FLOW OVER THE LOCAL
AREA.
FOR TONIGHT...KEPT ALL THUNDERSTORM MENTION OUT OF THE
FORECAST...DESPITE THE PRESENCE OF THE SURFACE TROUGH SLOWLY
MIGRATING TOWARD THE NORTHWEST CWA. WITH 700MB TEMPS INCREASING
INTO THE 12-15C RANGE AS A PRONOUNCED ELEVATED MIXED LAYER MOVES
IN FROM THE WEST...THIS SHOULD KEEP A STOUT CAP IN PLACE. A FEW
MODELS SUCH AS THE RAP AND 18Z NAM ATTEMPT TO BREAK OUT A FEW HIGH
BASED STORMS ACROSS NORTH CENTRAL/NORTHEAST NEB AT SOME POINT LATE
THIS AFTERNOON/THIS EVENING...BUT ANY OF THIS ACTIVITY SHOULD HOLD
OFF TO OUR NORTH. OTHERWISE...AS THE PRIMARY SURFACE LOW PRESSURE
SYSTEM MIGRATES EAST TOWARD THE IA/MN/NE/SD BORDER AREA
OVERNIGHT...A STEADY SOUTH BREEZE WILL PERSIST ACROSS MOST OF THE
CWA ALL NIGHT LONG...WITH BREEZES OF AT LEAST 20-25 MPH REMAINING
IN PLACE. LATE IN THE NIGHT HOWEVER...SPEEDS WILL START TO SLACKEN
ACROSS NORTHWEST COUNTIES AS THE SURFACE TROUGH FINALLY MOVES IN.
MADE LITTLE CHANGE TO LOW TEMPERATURES...STILL AIMING FOR MID 60S
FAR NORTHWEST TO LOW 70S EAST/SOUTHEAST...AND WOULD NOT BE
SURPRISED TO SEE MORE CENTRAL AREAS HOLD ABOVE THE 70-MARK AS
WELL.
TURNING TO THE 12Z-00Z DAYTIME HOURS MONDAY...A DRY FORECAST
CONTINUES AS A STOUT CAP WITH 700MB TEMPS ON THE ORDER OF 13-16C
REMAINS FIRMLY IN PLACE. ALOFT...THE FLOW REMAINS QUASI-ZONAL OVER
THE CENTRAL CONUS...AS ONE SHORTWAVE DEPARTS ACROSS THE NORTHERN MN
REGION...WHILE THE NEXT WAVE OF INTEREST TRANSITIONS EASTWARD
INTO THE NORTHERN ROCKIES. AT THE SURFACE...WIND TRENDS ARE A BIT
TRICKY THROUGH THE DAY...AS THE SURFACE TROUGH/WEAK COLD FRONT
SINKS AT LEAST PARTWAY INTO THE CWA DURING THE FIRST PART OF THE
DAY USHERING IN A LIGHT WESTERLY/NORTHERLY COMPONENT...BUT THEN
THE BOUNDARY RETREATS BACK NORTHWARD IN RESPONSE TO HIGH PLAINS
PRESSURE FALLS...WITH ALL AREAS BACK IN A LIGHT TO STEADY
SOUTHEAST BREEZE BY LATE AFTERNOON. HOWEVER...GIVEN THE WARM START
AND VERY WARM 850MB TEMPS IN PLACE...A RATHER HOT DAY IS STILL
ADVERTISED ESPECIALLY ACROSS THE SOUTHERN HALF OF THE CWA.
DIDN/T CHANGE HIGH TEMPS MUCH FROM PREVIOUS FORECAST...STILL
CALLING FOR A RANGE FROM MID 90S FAR NORTH...UPPER 90S ALONG THE
I-80 CORRIDOR...AND 100-105 ACROSS SEVERAL SOUTHERN COUNTIES
INCLUDING NORTH CENTRAL KS. HOWEVER...WITHIN MANY OF THESE HOTTEST
COUNTIES...ALSO LOWERED DEWPOINTS AT LEAST A FEW DEGREES FROM
PREVIOUS FORECAST PER MET GUIDANCE/RAW NAM SUGGESTION. AS A
RESULT...FORECAST APPARENT TEMPERATURES TOP OUT MAINLY IN THE
100-104 RANGE...WHICH IS JUST BARELY BELOW CRITERIA FOR HEAT
ADVISORY...ALTHOUGH IT MIGHT BE VERY CLOSE. FOR NOW...WILL
CONTINUE TO CARRY AN HWO MENTION OF NEAR-ADVISORY CRITERIA...BUT
NO ACTUAL HEADLINE SEEMS NECESSARY AT THIS POINT. ALONG THESE SAME
LINES...DESPITE RELATIVE HUMIDITY VALUES CRASHING INTO THE 10-20
PERCENT RANGE ACROSS SEVERAL WESTERN COUNTIES IN THE
AFTERNOON...THE SUSTAINED WIND SPEEDS OF 20 MPH NEEDED FOR RED
FLAG WARNING ISSUANCE DON/T APPEAR TO BE IN PLACE...SO NO FIRE
HEADLINES PLANNED.
LONG TERM...00Z TUESDAY THROUGH SUNDAY. CONCERNS IN THE EXTENDED
CONTINUE TO BE HEAT EARLY...FOLLOWED BY PRECIPITATION CHANCES MID
WEEK...AND THEN MORE HEAT BY THE END OF THE PERIOD.
LONG RANGE MODELS STILL VERY SIMILAR WITH OVERALL PATTERN THROUGH
THE PERIOD. AT THE START OF THE PERIOD...MONDAY EVENING...IT LOOKS
LIKE THERE WILL BE A MID LEVEL SHORT WAVE TROUGH MOVING INTO THE
NORTHERN ROCKIES AND THIS FEATURE SHOULD IMPACT OUR WEATHER TUESDAY
NIGHT AND WEDNESDAY AS IT CROSSES THE NORTHERN PLAINS. THE SOUTHERN
END OF THE MID LEVEL TROUGH AXIS IS SLATED TO MOVE THROUGH OUR CWA
BY WED EVENING WITH RIDGING STARTING TO BUILD OVER THE ROCKIES AT
THAT TIME AND THIS WILL TRANSLATE EAST AND ESTABLISH ITSELF OVER THE
CENTRAL PLAINS GOING INTO NEXT WEEKEND.
SENSIBLE WEATHER SHOULD BE DRY OVERNIGHT MONDAY AND THROUGH MUCH OF
THE DAY ON TUESDAY. AT THE SURFACE...SHOULD BE A WARM FRONT DRAPED
OVER THE NORTHERN CWA AT THE START OF THE PERIOD AND THIS IS SLATED
TO LIFT NORTH OVERNIGHT AS A SURFACE LOW PRESSURE LIFTS FROM SW TO
NE NEBRASKA. ON TUESDAY THE COLD FRONT WILL SLOWLY START TO APPROACH
THE CWA...EXTENDING FROM VTN TO LBF BY 12Z...AND FROM FULLERTON TO
CAMBRIDGE BY 00Z. QUESTION HERE IS HOW LONG WILL WE REMAIN CAPPED
TUESDAY AFTERNOON. LOOKING AT PROGGED 700 MB TEMPS IT WILL BE A
CLOSE CALL IN THE NW WHETHER CONVECTION CAN INITIATE LATE IN THE
AFTERNOON. OVERNIGHT TUESDAY AND INTO THE DAYTIME WED THE MID LEVEL
TROUGH SHOULD PUSH THE SURFACE FRONT THROUGH THE CWA. BY 06Z THE
NE/SW ORIENTED FRONT SHOULD BE ABOUT HALFWAY THROUGH THE CWA...AND
EXPECT IT TO PUSH THROUGH THE CWA SHORTLY AFTER SUNRISE.
MODEL GENERATED QPF SHOWING SOME DIFFERENCES IN WHERE THE BULK OF
THE RAIN WILL FALL. THE NAM AND THE GFS BOTH SHOW THE RAIN STARTING
ALONG THE SURFACE FRONT...BUT THE NAM HAS THE BULK OF THE OVERNIGHT
RAIN MAINLY NORTH OF OUR CWA ALONG THE MID LEVEL FRONT. LATEST GFS
CONTINUES THE TREND OF KEEPING THE RAIN FURTHER SOUTH
OVERNIGHT...PRODUCING MORE ACROSS OUR CWA. IT ALSO SHOWS THE MID
LEVEL FRONT FURTHER SOUTH AND MUCH CLOSER TO THE SURFACE FRONT. THE
OLD EC SHOWED MORE OF A NORTHERN SOLUTION AND WILL TAKE A LATE LOOK
AT THE 12Z RUN BEFORE MAKING A FINAL CALL. CHECKING OTHER
MODELS...BOTH THE SREF AND GEM SUPPORT A MORE NORTHERN SOLUTION
WHILE THE UKMET MORE IN LINE WITH THE SOUTHERN GFS SOLUTION.
WED AND THU STILL SHOWING UNCERTAINTY IN THE DETAILS AS LATEST GFS
NOW BRINGS ANOTHER MID LEVEL WAVE THROUGH THE NORTHERN PLAINS ON
THURSDAY NIGHT WHILE THE OLD EC AND MOST OF THE OTHER MODEL
SOLUTIONS NOT SHOWING THIS AT ALL. THUS WILL LEAN TOWARD CONSENSUS
AND WHILE IT MAY NOT BE TOTALLY DRY ON THURSDAY...BELIEVE THE GFS IS
OVERDONE...ESPECIALLY GIVE THE HIGH DEWPOINT BIAS AS OF LATE
CANNOT RULE OUT SEVERE POSSIBILITIES TUESDAY NIGHT THROUGH WEDNESDAY
STARTING IN THE NW PART OF THE CWA TUESDAY LATE AFTN/EVE AS MUCAPE
AND DEEP LAYER SHEAR BOTH RESPECTABLE VIA THE EC. SHEAR MUCH LESS IN
THE SOUTHERN PART OF THE CWA. BY WED LATE AFTERNOON BEST SEVERE
PARAMETERS LOOK TO BE SOUTH OF THE CWA ACCORDING TO OLD EC RUN BUT A
LITTLE CHANGE IN TIMING COULD PUT PART OF OUR CWA IN THE PICTURE.
FRIDAY THROUGH SUNDAY LOOKS DRY AS BOTH SOLUTIONS CONTINUE TO BUILD
IN A STOUT RIDGE BY THEN. ONLY FLY IN THE OINTMENT WOULD BE IF WE
END UP WITH A FEW RIDGE RUNNERS AROUND THE RING OF FIRE THAT CLIP A
PART OF OUR AREA. THAT DOES NOT LOOK TO BE THE CASE AT THIS
TIME...BUT HAS BEEN SOMEWHAT COMMON THE PAST COUPLE OF YEARS WITH
THIS TYPE OF JULY PATTERN SO WILL NEED TO BE WATCHED.
AVIATION...18Z KGRI TAF. VFR CEILING AND VISIBILITY FORECAST
THROUGH THE PERIOD...WITH ONLY SOME PASSING MID-HIGH CLOUDS AND
ESSENTIALLY ZERO RISK OF THUNDERSTORMS. AS A DEEPENING SURFACE LOW
PRESSURE SYSTEM PASSES BY TO THE NORTH...STEADY SOUTH BREEZES WILL
PERSIST THROUGH AT LEAST THE FIRST 15 HOURS OF THE PERIOD...WITH
GUST POTENTIAL TO AROUND 26KT. THERE COULD BE BIT OF A LULL IN
THESE GUSTS DURING THE EVENING...BUT HAVE NOT DEPICTED THIS FOR
NOW. OVERNIGHT...MAY HAVE TO CONSIDER ADDING LOW LEVEL WIND
SHEAR...AS SOUTHERLY SPEEDS INCREASE TO AROUND 50KT BETWEEN
1500-2000 FT AGL. HOWEVER...WILL OMIT FOR NOW AS DIRECTIONAL
CHANGE IS FAIRLY MINIMAL...AND THE SPEED DIFFERENCE IS FAIRLY
MARGINAL FOR A FORMAL LOW LEVEL WIND SHEAR MENTION. LATE TONIGHT
INTO MONDAY MORNING...AN APPROACHING SURFACE TROUGH AXIS WILL
DECREASE SURFACE WIND SPEEDS A BIT...AND START TURNING THEM MORE
WESTERLY. TOWARD THE VERY END OF THE PERIOD...A LIGHT NORTHERLY
BREEZE MAY TAKE HOLD BEHIND A WEAK COLD FRONT...BUT WILL DEFER TO
LATER SHIFTS TO ADD THIS WIND SHIFT.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
402 PM EDT MON JUN 18 2012
.SYNOPSIS...
A SERIES OF SURFACE WARM FRONTS WILL LIFT ACROSS THE NORTH COUNTRY
OVER THE NEXT COUPLE OF DAYS. THIS WILL RESULT IN MUCH ABOVE NORMAL
TEMPERATURES BY WEDNESDAY...ALONG WITH MAINLY DRY CONDITIONS. A FEW
SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE ON TUESDAY
AFTERNOON AND EVENING NEAR THE INTERNATIONAL BORDER.
HAZY...HOT...AND HUMID CONDITIONS DEVELOP ON WEDNESDAY INTO THURSDAY
WITH HIGHS WELL INTO THE 90S AND LOWS ONLY IN THE UPPER 60S TO MID
70S.
&&
.NEAR TERM /UNTIL 8 AM TUESDAY MORNING/...
AS OF 400 PM EDT MONDAY...FCST CHALLENGE TONIGHT WL BE SCHC OF POPS
ACRS THE SLV AND AREAL COVERAGE OF CLOUDS AND ASSOCIATED IMPACTS
ON TEMPS. WATER VAPOR SHOWS MID/UPPER LVL RIDGE ALONG THE EAST
COAST WITH A STRONG DIVERGENCE SIGNATURE IN THE HGHT FIELDS ACRS
OUR CWA. MEANWHILE...FAST WESTERLY FLW WITH SEVERAL EMBEDDED 5H
VORTS AND SOME MID LVL MOISTURE IS LOCATED ACRS THE NORTHERN
PLAINS INTO THE NORTHERN GREAT LAKES. THE INITIAL SURGE OF MID RH
AND WEAK OMEGA FIELDS WL DISSIPATE ACRS OUR WESTERN CWA
TONIGHT...AND MAY PRODUCE A VERY SCHC FOR A SHOWER ACRS THE SLV.
MEANWHILE...SE ANTICYCLONIC FLW AROUND SFC HIGH PRES LOCATED OFF
THE COAST OF MAINE WL CONT TO ADVECT IN LLVL MOISTURE TONIGHT ACRS
EASTERN/CENTRAL VT. NAM12/BTV4 AND RAP ALL SHOW SFC TO 800MB RH
PROFILES INCREASING AFT 04Z TONIGHT...WITH SOME INDICATION OF
FOG/BR DEVELOPMENT. WL MENTION CLOUDS WITH SOME PATCHY FOG
POSSIBLE. TEMPS WL RANGE FROM THE L/M 50S NEK/EASTERN VT/SLK TO
M60S CPV/SLV. CPV/SLV SOUNDINGS SHOW WELL MIXED BL...WHICH WL
RESULT IN SOUTHERLY WINDS AT 5 TO 15 MPH OVERNIGHT...WITH SOME
HIGHER GUSTS NEAR THE LAKE.
&&
.SHORT TERM /8 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 400 PM EDT MONDAY...
...CHANCE OF THUNDERSTORMS ON TUES AFTN/EVENING FOLLOWED BY
RECORD BREAKING HEAT ON WEDNESDAY...
...HEAT ADVISORY MAYBE NEEDED FOR HEAT INDEX VALUES NEAR 100 DEGREES
ON WEDNESDAY AND THURSDAY AFTERNOONS...
MID/UPPER LVL RIDGE WL REDEVELOP ACRS THE OHIO VALLEY AND PUSH TWD
THE NE CONUS ON TUES INTO WEDS...AS BELT OF ACTIVE WESTERLY WINDS
LIFTS NORTH OF OUR CWA BY LATE WEDS. HOWEVER...AS STRONG LLVL WAA
DEVELOPS ON TUES AND SEVERAL CONVECTIVELY INDUCED 5H VORTS SLIDE
ALONG THE BOUNDARY IN NW FLW ALOFT...SCATTERED SHOWERS/STORMS WL BE
POSSIBLE ON TUES. THINKING TWO ROUNDS OF SHOWERS/STORMS WL BE
POSSIBLE WITH LIMITED AREAL COVERAGE. STILL PLENTY OF UNCERTAINTY
WITH REGARDS TO LOCATION AND SVR POTENTIAL. FIRST LINE WL BE
ASSOCIATED WITH DECAYING UPSTREAM CONVECTION ACRS THE CENTRAL GREAT
LAKES OVERNIGHT AND WL ENTER OUR WESTERN CWA AROUND 12Z TUES. THIS
WL TRACK EAST AND DISSIPATE IN STABLE AIRMASS PROVIDED BY SE
MARITIME AIR ACRS CENTRAL/EASTERN VT. BEST INSTABILITY BTWN 12Z-15Z
WL BE ACRS THE SLV/DACKS WITH CAPE VALUES BTWN 600-900 J/KG. FEEL
INITIAL LINE OF MAINLY SHOWERS WL ADD LLVL MOISTURE AND BE THE
LEADING EDGE TO A MUCH MORE HUMID/WARMER AIRMASS FOR THE AFTN HRS.
MEANWHILE....SECONDARY S/W ENERGY DEVELOPS ACRS SOUTHERN CANADA LATE
TUES AFTN...AND DIVES SE TWD THE SLV AND OUR NORTHERN CWA BY EARLY
TUES EVENING. THE BEST ULVL DYNAMICS ASSOCIATED WITH S/W ENERGY AND
WESTERLY JET WL BE LOCATED ACRS OUR NORTHERN CWA...ALONG WITH BEST
DEEP LAYER SHEAR. NAM/GFS SHOW 0-6KM SHEAR PARAMETERS BTWN 35 AND 40
KNOTS...WHILE CAPE VALUES INCREASE BTWN 2400 AND 2800 J/KG. BIG
QUESTION WL BE IF CONVECTION TRACKS SE INTO OUR NORTHERN CWA OR
STAYS JUST NORTH OF THE INTERNATIONAL BORDER...WHERE THE WESTERLY
FLW IS THE STRONGEST. GIVEN...THE SVR PARAMETERS IF ANY CONVECTION
CROSSES THE BORDER...THE POTENTIAL WL EXIST FOR STRONG TO SVR
STORMS...WITH SOME ORGANIZATION TO THE CONVECTION LIKELY.
GIVEN...THE UNCERTAINTY IN DEVELOPMENT AND PLACEMENT/TRACK OF
CONVECTIVE VORT...WL MENTION CHC POPS ALONG THE INTERNATIONAL BORDER
AND SCHC CENTRAL...AND NIL POPS SOUTH. ALSO...WL MENTION A BRIEF
STATEMENT WITH REGARDS TO THUNDERSTORM DEVELOPMENT IN HWO. TEMPS
TUES WL BE TRICKY WITH EXPECTED CLOUDS...BUT THINKING NEAR 80F
EASTERN VT TO NEAR 90F CPV/SLV. VERY WARM AND MUGGY NIGHT EXPECTED
ON TUES INTO WEDS...AS DWPT TEMPS CLIMB INTO THE 60S AND SOUTHERLY
WINDS CONT WITH AREAS OF HAZY. LOWS WL RANGE FROM U50S NEK TO NEAR
70F SLV/CPV.
WEDS...MID/UPPER LVL RIDGE CONTS TO BUILD ACRS OUR CWA...WITH AXIS
OF WESTERLY SHIFTING INTO CANADA AND NORTHERN MAINE. NAM/GFS/GEM ALL
HINT AT THE POTENTIAL FOR A LATE AFTN COMPLEX OF STORMS TO DEVELOP
ACRS SOUTHERN CANADA AND DIVE SE TWD THE NEK ON WEDS AFTN...IN THE
NW FLW ALOFT. GIVEN...DEEP SUBSIDENCE/CAP ACRS MOST OF OUR CWA...WL
NOT MENTION ANY POPS...BUT KEEP SCHC ACRS NORTHERN VT FOR THE
POTENTIAL OF SOME CONVECTION. OTHERWISE...THE BIG STORY WL BE THE
POSSIBLE RECORD BREAKING HEAT ON WEDS AFTN. PROGGED 85H TEMPS ARE
NEAR 20C WITH 925MB TEMPS AROUND 25C...WHICH WITH GOOD MIXING PRE
SOUNDING DATA SUPPORT HIGHS IN THE U80S MTNS TO M90S VALLEYS. SEE
CLIMO SECTION BLW FOR RECORDS. INTERESTING...WHEN VIEWING THE CAPE
PROFILES ON WEDS...SHOWS LOTS OF CAPE THRU 18Z WITH VALUES OVER
3000 J/KG...BUT AS MIXING INCREASES AND SFC DWPTS DROP FROM NEAR
70F BACK INTO THE 50S/L60S...CAPE VALUES DROP BTWN 500-1000
J/KG...AS TEMPS CLIMB INTO THE 90S. ANOTHER VERY WARM AND MUGGY
NIGHT ANTICIPATED ON WEDS NIGHT INTO THUR...WITH LOWS IN THE 60S TO
M70S.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 347 PM EDT MONDAY...STRONG UPPER RIDGE IN PLACE ALONG THE
MID ATLANTIC COAST THURSDAY. HOT AIRMASS REMAINS IN PLACE WITH 850
MB TEMPERATURES AROUND 20C. VALLEY LOCATIONS SHOULD ONCE AGAIN TOP
90 DEGREES...WITH PORTIONS OF CHAMPLAIN VALLEY AND CONNECTICUT
RIVER VALLEY REACHING INTO THE MID 90S. HEIGHTS BEGIN TO FALL
LATER THURSDAY INTO THURSDAY NIGHT AND CONTINUE TO FALL DURING
FRIDAY. COLD FRONT WILL MAKE ITS WAY SOUTHEAST ACROSS THE REGION
THURSDAY NIGHT INTO EARLY FRIDAY MORNING. MODELS HAVE COME INTO
BETTER AGREEMENT REGARDING TIMING OF THE FRONT. MOISTURE IS
LIMITED WITH THE FRONT...AND TIMING OF FROPA DOES NOT SUPPORT
WIDESPREAD CONVECTION. HAVE CONTINUED WITH CHANCE POPS FOR
THURSDAY AFTERNOON OVER FAR NORTHERN ZONES AND FOR ENTIRE AREA
THURSDAY NIGHT. MAINLY DRY CONDITIONS EXPECTED FRIDAY AS HIGH
PRESSURE BUILDS INTO THE REGION. MAX TEMPERATURES WILL STILL BE
ABOVE NORMAL...BUT THEY WILL BE ABOUT 10 DEGREES COOLER THAN
THURSDAY WITH HIGHS IN THE UPPER 70S AND LOWER 80S. TEMPERATURES
WILL BE WILL BE WITHIN A FEW DEGREES OF SEASONAL NORMS OVER THE
WEEKEND. A SERIES OF SHORTWAVE TROUGHS WILL MOVE ACROSS THE REGION
IN FAST NORTHWEST FLOW...BUT SURFACE HIGH PRESSURE REMAINS OVER
THE AREA INTO SUNDAY...SO MAINLY DRY CONDITIONS EXPECTED. CHANCES
FOR SHOWERS INCREASE LATER SUNDAY INTO MONDAY AS A STRONGER
DISTURBANCE IN THE NORTHWEST FLOW ALOFT APPROACHES. TEMPERATURES
WILL ALSO BE COOLER MONDAY DUE CLOUD COVER AND CHANCE OF SHOWERS.
&&
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
THROUGH 18Z TUESDAY...GULF OF MAINE MARINE LAYER STRATUS WITH
VFR/MVFR CEILINGS EVIDENT IN IR SATELLITE/OBSERVATIONS HAS MADE
IT INTO RUT/MPV UNDER SOUTHEAST/SOUTH SFC FLOW. OTHERWISE VFR
CONDITIONS PREVAIL THIS AFTERNOON. CHALLENGE WILL BE WHEN THE
STRATUS LAYER LIFTS...WHICH DOESN`T LOOK LIKE IT WILL HAPPEN UNTIL
EARLY EVENING. HAVE WENT WITH SCT028 ONCE STRATUS LAYER LIFTS WITH
VFR CONTINUING THROUGH THE OVERNIGHT. GUSTY SOUTH WINDS (UP TO 25
KTS) CONTINUE THROUGH THE AFTERNOON BEFORE SUBSIDING LATE
AFTERNOON/EARLY EVENING.
FOR TUESDAY...CONDITIONS ONCE AGAIN SIMILAR TO TODAY WITH VFR
AND GUSTY SOUTH/SOUTHWEST WINDS (GUSTS 17-22KTS). WITH FLOW
BECOMING MORE SOUTHERLY THINK MVFR STRATUS AT RUT/MPV IS LESS OF A
POSSIBILITY THOUGH WILL MONITOR CLOSELY.
OUTLOOK 18Z TUESDAY THROUGH FRIDAY...MAINLY VFR CONDITIONS THROUGH
THE PERIOD UNDER HIGH PRESSURE. WIDELY SCATTERED SHOWERS AND
ISOLATED THUNDER EACH DAY TUESDAY THROUGH WEDNESDAY...MAINLY
DURING THE AFTERNOON/EVENING HOURS. BRIEF MVFR POSSIBLE IN ANY
PRECIPITATION. CHANCES FOR THUNDERSTORMS INCREASE LATER THURSDAY
WITH APPROACH OF COLD FRONT.
&&
.MARINE...
AS OF 318 PM EDT MONDAY...LAKE WIND ADVISORY REMAINS IN EFFECT.
SOUTHERLY WINDS CONTINUE TO BLOW IN THE 15 TO 25 KNOT RANGE THIS
AFTERNOON. THESE WINDS WILL CONTINUE IN THIS RANGE THROUGH THE
OVERNIGHT. WAVES OF 1 TO 3 FEET ARE EXPECTED.
&&
.CLIMATE...
TUESDAY THROUGH THURSDAY JUNE 19TH-21ST WILL FEATURE VERY WARM
TEMPERATURES AND INCREASING HUMIDITY LEVELS...WITH SOME POTENTIAL
FOR RECORD HIGH MAXIMUM TEMPERATURES AND/OR RECORD HIGH MINIMUM
TEMPERATURES TO BE BROKEN. THE FOLLOWING ARE A LIST OF RECORD HIGH
MAXIMUM AND MINIMUM TEMPERATURES FOR OUR CLIMATE SITES WITH LONG-
ESTABLISHED CLIMATE RECORDS.
JUNE 19TH:
BTV 100 (1995) / 78 (1896)
MSS 94 (1955) / 73 (1995)
MPV 95 (1995) / 67 (2001)
IV4 98 (1995) / 69 (1994)
MMN 78 (1995) / 61 (1995)
JUNE 20TH:
BTV 94 (1988) / 78 (1893)
MSS 91 (1953) / 71 (1953)
MPV 89 (1953) / 67 (1976)
1V4 97 (1995) / 70 (1976)
MMN 77 (1995) / 65 (1983)
JUNE 21ST:
BTV 97 (1941) / 72 (1893)
MSS 95 (1953) / 70 (1953)
MPV 92 (1953) / 66 (1953)
1V4 93 (1941) / 69 (1923)
&&
.EQUIPMENT...
AS OF 423 AM MONDAY...COMMUNICATION PROBLEMS AT THE KVSF
(SPRINGFIELD VT) ASOS ARE KEEPING OBSERVATIONS FROM BEING
TRANSMITTED. FAA TECHNICIANS ARE AWARE OF THE PROBLEM.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...TABER
NEAR TERM...TABER
SHORT TERM...TABER
LONG TERM...RJS
AVIATION...LOCONTO
MARINE...
CLIMATE...
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS RALEIGH NC
130 AM EDT MON JUN 18 2012
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL MOVE THROUGH THE REGION ON MONDAY.
HIGH PRESSURE ALOFT WILL STRENGTHEN BY THE MIDDLE OF THE WEEK. THIS
WILL RESULT IN VERY WARM HIGH TEMPERATURES FOR THE MIDDLE AND END OF
THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 955 PM SUNDAY...
MAINLY MID AND HIGH LEVEL CLOUD COVER IS INCREASING ACROSS THE AREA
THIS EVENING FROM WEST TO EAST IN ADVANCE OF AN APPROACHING
MID/UPPER LEVEL DISTURBANCE... CURRENTLY LOCATED OVER THE OH/TN
VALLY REGIONS. THE MAIN S/W TROUGH IS NOT EXPECTED TO MOVE THROUGH
THE AREA UNTIL MONDAY AFTERNOON. THE SHOWERS AND ISOLATED STORMS
THAT DEVELOPED ACROSS THE HIGHER TERRAIN THIS AFTERNOON INTO THE
EARLY EVENING ARE DWINDLING IN COVERAGE. UPPER AIR ANALYSIS THIS
EVENING CONTINUED TO SHOW RIDGING ALOFT HANGING ON ACROSS THE
AREA.... WITH THE BEST UPPER LEVEL SUPPORT PASSING TO THE NORTH OF
CENTRAL NC. GIVEN THIS AND LACK OF OVERALL INSTABILITY WILL LOWER
POPS... ONLY KEEPING A SLIGHT CHANCE OF SHOWERS ACROSS THE
NORTHWEST/FAR NORTHERN PIEDMONT (AS SOME MODELS CONTINUE TO SHOW A
REMOTE POSSIBLY OF A SHOWER OR TWO THERE). HOWEVER... WITH LACK OF
ANY SIGNIFICANT S/W`S NOTED ON THE NAM... GFS AND RUC ON THE 1.5 PVU
SURFACE AND MODELS NOT SHOWING EVEN MUCH/IF ANY MUCAPE.... THINK
THIS MAY STILL BE A BIT OVERDONE. STILL EXPECT LOW TO RANGE FROM
GENERALLY THE UPPER 50S EAST TO THE LOWER 60S WEST (GIVEN MORE CLOUD
COVER AND INCREASING SOUTHERLY FLOW ACROSS THE WEST)... WITH PERHAPS
A FEW MID 50S IN THE USUAL COOL SPOTS ACROSS THE EAST (WHERE CLOUD
COVER SHOULD BE THE LEAST).
&&
.SHORT TERM /MONDAY AND MONDAY NIGHT/...
AS OF 305 PM SUNDAY...
AS THE MOISTURE AND MODEST LIFT RUN INTO A DRIER AIR MASS FURTHER TO
THE EAST OF THE AREA...COINCIDENT WITH THE PASSAGE OF VORTICITY ON
THE 1.5PVU SURFACE...CURRENTLY EXPECT THE CHANCES FOR MINIMAL
MEASURABLE PRECIPITATION TO DIMINISH SOME...AND TOWARD KRWI ANY
PRECIPITATION MAY END UP BEING MORE IN THE FORM OF SPRINKLES. AS THE
DAY PROGRESSES...INSTABILITY OVER THE AREA IS ONLY FORECAST TO BE
MODEST UNDER WEAK 0-6KM SHEAR AT OR LESS THAN 20KT...WITH MLCAPE IN
THE LOWEST KILOMETER AROUND 500J/KG BY 21Z. LIFTED INDICES FALL TO
AS MUCH AS -3C OR -4C...ESPECIALLY ON THE GFS...TO THE NORTHWEST OF
CENTRAL NORTH CAROLINA...AND BASED ON THE THERMAL WIND PROFILE
FOLLOWING THE 1000-500MB THICKNESSES...THUNDERSTORMS THAT DEVELOP
OVER HIGHER ELEVATIONS HAVE THE POTENTIAL TO MOVE INTO CENTRAL NORTH
CAROLINA DURING THE AFTERNOON. ONCE AGAIN...FOLLOWED A BLEND OF THE
WETTER GFS AND THE DRIER NAM...MORE TOWARD THE COMPROMISE SREF...TO
FORECAST ISOLATED THUNDERSTORMS MAINLY ALONG AND WEST OF U.S. 1 WITH
HEATING MONDAY AFTERNOON...WITH SCATTERED CHANCES TOWARD KINT.
MAINTAINED A SLIGHT CHANCE OF A SHOWER OVERNIGHT MAINLY NORTH OF A
LINE FROM ALBEMARLE TO GOLDSBORO FOR LINGERING SHOWERS MOVING
EAST...OR POSSIBLY MOVING INTO THE AREA FROM THE NORTH OVERNIGHT
MONDAY ACCOMPANIED BY ANOTHER 1.5PVU MODEST VORTICITY MAXIMUM. ONLY
MODEST INSTABILITY AND LAPSE RATES...THE LATTER 6C/KM TO 6.25C/KM...
PLUS WEAK SHEAR SHOULD KEEP THE POTENTIAL FOR A SEVERE STORM
RELATIVELY LOW...NOT COMPLETELY NON-ZERO TOWARD THE TRIAD...BUT LOW
ENOUGH TO AVOID MENTION IN THE HWO FOR NOW. HIGHS AND LOWS MONDAY
AND MONDAY NIGHT WERE FORECAST CLOSE TO GUIDANCE...AT OR A DEGREE
COOL MONDAY EXCEPT OVER THE SOUTHWEST PIEDMONT...WHERE THE HIGHEST
THICKNESSES AND POSSIBLY THE GREATEST AMOUNT OF SUN RELATIVE TO THE
REST OF CENTRAL NORTH CAROLINA IS EXPECTED. FORECAST LOWS AT OR A
DEGREE WARM MONDAY NIGHT UNDER A MOIST AIR MASS WITH AREAS OF CLOUDS
AND SOME SOUTHWEST WIND.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
AS OF 215 PM...
TUESDAY THROUGH WEDNESDAY NIGHT
SURFACE PATTERN QUITE STATIC DURING THIS PERIOD WITH HIGH
PRESSURE OFF THE CAROLINA COAST. CHANGES ALOFT HOWEVER AS WINDS
SHIFT TOWARD EAST AND THE AIR MASS ABOVE 12000 FEET DRYS WEDNESDAY.
PRECIPITABLE WATERS ABOVE 1.5 INCHES TUESDAY AFTERNOON WITH
MINIMAL INSTABILITY. THE WIND FIELD CONTINUES SUMMER TIME WEAK
AND SURFACE TRIGGERS OTHER THAN AFTERNOON HEATING APPEAR ABSENT.
POTENTIAL ENERGY LOW AND CAN SEE NO MORE THAN SLIGHT RAIN CHANCES.
WITH DRYING ALOFT... RAIN CHANCES UNDER TEN PERCENT... PERHAPS
CLOSE TO ZERO.
HIGH TEMPERATURES TUESDAY AROUND 90. TUESDAY NIGHT LOW TEMPERATURES
NEAR 67. WITH A WARMER START TO THE DAY AND MINIMALLY HIGHER
THICKNESSES... HIGH TEMPERATURES WEDNESDAY MOSTLY LOWER 90S. LOW
TEMPERATURES 66 TO 70 WEDNESDAY NIGHT.
THURSDAY THROUGH SUNDAY
FLOW ACROSS THE NORTHERN UNITED STATES IS ZONAL THURSDAY BEFORE
SHIFTING TOWARD NORTHWEST AS RIDGING BUILDS IN THE ROCKIES AND
BEGINS TO SLOWLY PUSH EAST. SURFACE HIGH PRESSURE PERSISTS OFF THE
CAROLINA COAST. THIS WILL ALLOW THE RUN OF ABOVE NORMAL TEMPERATURES
TO CONTINUE INTO THE COMING WEEKEND. THE QUESTION WILL BE... HOW
WARM? 850 MILLIBAR PRESSURE SURFACES FALL A BIT THURSDAY BEFORE
LEVELING OFF. SURFACE HEAT WILL BE LARGELY DETERMINED BY HOW STRONG
LESS SIDE OR OTHER TROUGHING AT THE SURFACE BECOMES. MODELS HAVE
BEEN PROMISING SUCH TROUGHING (WITH POTENTIAL MID TO UPPER 90S) FOR
SEVERAL DAYS IN THE DAY SIX OR SEVEN FORECAST... YET IT AS OF YET
REMAINS UNVERIFIED. SEE NO REASON TO TRUST MODELS NOW... AND WILL
KEEP HIGH TEMPERATURES NO HIGHER THAN 89 TO 94. LOW TEMPERATURES
66 TO 71.
CURRENT TIMING ON A POTENTIAL TROUGH PASSAGE AND ASSOCIATED RAIN
CHANCE WOULD PLACE THE BEST RAIN CHANCE MID TO LATE AFTERNOON
FRIDAY... WITH THE TROUGH EXITING TO THE SOUTHEAST FRIDAY NIGHT.
MINIMAL PUSH WITH THIS TROUGH WITH LITTLE CHANGE IN AIR MASS BEHIND
THE SYSTEM. WINDS ALOFT MOSTLY EAST TO NORTHEAST AND WEAK WITH NO
UPPER LEVEL SUPPORT TO SPEAK OF FOR CONVECTION. THUS OTHER THAN
FRIDAY AFTERNOON AND EVENING...CHANCES LESS THAN TEN PERCENT... WITH
AROUND 25 PERCENT FRIDAY AFTERNOON NORTH... 20 PERCENT SOUTH.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 115 AM MONDAY...
A WEAK UPPER LEVEL DISTURBANCE WILL DIVE SOUTHEAST...APPROACHING
THE CENTRAL/SOUTHERN APPALACHIANS BY DAYBREAK...AND WILL MOVE ACROSS
CENTRAL NC DURING THE AFTERNOON. WARM MOIST AIR ADVECTION IN ADVANCE
OF THIS WAVE WILL RESULT IN A BROKEN/OVERCAST MID CLOUD DECK
OVERSPREADING THE AREA WITH A FEW BRIEF PASSING SHOWERS.
OTHERWISE...OUTSIDE OF SOME ISOLATED AREAS OF MVFR VSBYS IN PATCHY
FOG AT KRWI AND POSSIBLY KFAY...VFR CONDITIONS ARE EXPECTED
OVERNIGHT.
STRONG DAYTIME HEATING COMBINED WITH THE PASSAGE OF THE UPPER LEVEL
DISTURBANCE WILL LEAD TO ISOLATED TO WIDELY SCATTERED CONVECTION
ACROSS THE AREA THIS AFTERNOON...WITH CONDITIONS BIT MORE FAVORABLE
TO SUPPORT SLIGHTLY BETTER COVERAGE OVER THE HIGHER TERRAIN OF
WESTERN NC. THE EXPECTED COVERAGE IS TOO LOW FOR MENTION AT KGSO AND
KINT AT THIS TIME.
OUTLOOK...
AN UPPER LEVEL RIDGE WILL INTENSIFY OVER THE REGION THROUGH THE
WORK WEEK. OUTSIDE OF SOME ISOLATED CONVECTION ON TUESDAY
AND SOME PREDAWN FOG/HAZE...STRONG SYNOPTIC SCALE SUBSIDENCE WILL
RESULT IN PREDOMINATELY VFR CONDITIONS THROUGH THURSDAY. THE NEXT
CHANCE FOR MORE WIDESPREAD AVIATION CONCERNS COULD COME ON FRIDAY
WITH THE PASSAGE OF A COLD FRONT.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BSD/DJF
NEAR TERM...BSD
SHORT TERM...DJF
LONG TERM...99
AVIATION...CBL
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
840 PM CDT TUE JUN 19 2012
.FORECAST CHALLENGE CONCERNS CONTINUED CONVECTIVE CHANCES...STRENGTH
AND COVERAGE. SURFACE LOW AND E-W ORIENTED WARM FRONTAL BOUNDARY HAS
SHOWN VERY LITTLE MOVEMENT THIS EVENING WITH SURFACE LOW JUST EAST
OF HON WITH WARM FRONTAL BOUNDARY JUST SOUTH OF LINE FROM ATY TO STC
AND DLH. SO FAR AIRMASS VCNTY BOUNDARY VERY CAPPED HOWEVER RECENT
RADAR TRENDS SHOWING SOME CONVECTIVE INITIATION. FARTHER NORTH
ELEVATED CONVECTION MAINLY OVER THE LAKES REGION HAS SHOWN A
DECREASE IN BOTH INTENSITY AND COVERAGE. HIGH RESOLUTION RAPID
REFRESH MODEL (HRRR) DOING AN EXCELLENT JOB SO FAR ON CONVECTIVE
TRENDS. HRRR GRADUALLY WEAKENS NORTHERN CONVECTION FOCUSING MORE
SOUTHWARD TOWARDS WARM FRONT OVERNIGHT. ANY FURTHER SEVERE POTENTIAL
LOOKING MORE AND MORE LIKE IT MAY SLIP JUST ALONG OR SOUTH OF OUR SE
FORECAST AREA. BASED ON THIS SOLUTION WHICH IS TOUGH TO ARGUE WITH
AT THIS POINT FEEL BEST CHANCES WILL BE CONFINED TO FAR SE FA
REMAINDER OF THE OVERNIGHT. FARTHER NW PCPN MORE SPOTTY/ISOLATED
WITH SLIGHTLY MORE ORGANIZED BAND OF SHRA OVER NW DVL BASIN. WILL
MAKE SOME POPS ADJUSTMENTS BASED ON ABOVE TRENDS. WITH FAIRLY
QUASISTATIONARY SURFACE BOUNDARY COLUMN ONLY COOLS SLIGHTLY
OVERNIGHT. CLOUDS WILL DETERMINE TEMPERATURE DROP OVERNIGHT.
CURRENTLY BEST POTENTIAL FOR ANY BREAKS IN CLOUDS WILL BE ACROSS FAR
NW FA WHERE LOWEST MINIMUMS. WILL MAKE ADJUSTMENTS TO HOURLY CURVE
HOWEVER CURRENT MINIMUMS SEEM REASONABLE.
&&
.AVIATION...TAFS CONTINUE TO BE A CHALLENGE MVFR/IFR CIGS STILL
SPATTERED ACROSS FA WITH GENERALLY MORE VFR CONDITIONS ACROSS
NORTHERN FA. WITH CIGS HOLDING GOOD PART OF NIGHT NOT TOO MUCH OF A
CHANGE PLANNED. WILL LIKELY SEE SOME PATCHY BR BUT TOO TOUGH TO
PINPOINT AND COULD BE FAIRLY ISOLD.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
VOELKER
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
702 PM EDT MON JUN 18 2012
.SYNOPSIS...
AFTER TONIGHT THE STORM TRACK SHOULD BE NORTH OF THE AREA. A HOT
AND HUMID AIRMASS WILL BUILD ACROSS THE REGION FOR TUESDAY AND
WEDNESDAY. A COLD FRONT IS EXPECTED TO MOVE ACROSS THE AREA
THURSDAY.
&&
.NEAR TERM /THROUGH TUESDAY/...
SHOWERS AND EMBEDDED THUNDERSTORMS ACROSS THE SOUTH AND EAST
PORTIONS OF THE FORECAST AREA. THUNDERSTORMS MAINLY CONFINED TO
THE FAR SOUTHEAST AS OF 2250Z. TIMED HOURLY POPS WITH THIS TO THE
SOUTHEAST THROUGH 02Z OR SO THEN MAINLY DRY OVERNIGHT. SATELLITE
SHOWING PLENTY OF DEBRIS CLOUDS LINGERING OVER MUCH OF THE AREA
BUT EVEN THOSE SHOULD BEGIN TO BECOME MORE SCATTERED AND CLEAR OUT
DURING EARLY TONIGHT.
SATELLITE AND RADAR SHOWING ANOTHER COMPLEX OVER NRN LAKE MI THAT
IS MOVING ESE. MODELS PROJECTING THIS TO CONTINUE MOVING ACROSS
LOWER MI EARLY TONIGHT...THEN SOME DIVERGENCE LOOKING AT THE
LATEST HRRR RUNS...NAM AND SREF AS TO HOW THIS WILL PROGRESS. HRRR
WANTS TO WEAKEN THIS COMPLEX BEFORE IMPACTING THE FORECAST
AREA...WHILE OTHER MODELS WANT TO MOVE IT NORTHEAST OF THE AREA. FOR
NOW WILL KEEP SOME POPS OVER LAKE ERIE LATER TONIGHT...AND WILL
MONITOR FOR NEXT UPDATE. NO CHANGES TO TEMPS. PREVIOUS DISCUSSION
BELOW.
COMPLEX HAS TRAVELED A LONG WAY AND HAS REMAINED FAIRLY STEADY IN
TERMS OF STRENGTH. WILL MOVE THIS COMPLEX EAST-SOUTHEAST ACROSS
THE AREA. NOT SURE HOW FAR TO TAKE CATEGORICAL POPS THOUGH. WILL
UPDATE AS NEEDED. RIDGE WILL BE BUILDING INTO THE AREA TONIGHT AND
SHOULD KEEP ANY OVERNIGHT COMPLEXES NORTH OF THE AREA. WILL LIKELY
CONTINUE TO HAVE SOME HIGH/DEBRIS CLOUDS AND THEREFORE DID NOT
CLEAR THE ENTIRE AREA OUT OVERNIGHT. MILD TONIGHT.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
STRONG RIDGE BUILDS OVERHEAD FOR TUESDAY AND WEDNESDAY. WILL HAVE
TEMPERATURES PUSHING ABOVE 90 DEGREES AT MOST LOCATIONS. NOT
EXPECTING ANY PRECIP TO BREAK OUT EITHER.
MODELS CONSISTENT ON TAKING A COLD FRONT ACROSS THE AREA ON
THURSDAY. AT LEAST SCATTERED SHOWERS/TS WITH THIS.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
COLD FRONT MOVES THROUGH THE AREA ON THURSDAY LEAVING HIGH PRESSURE
TO BUILD IN FOR FRIDAY. IF THE FRONT SLOWS WE COULD GET SOME
LINGERING SHOWERS FRIDAY MORNING SOUTHEAST BUT FOR NOW WILL GO DRY.
GFS AND ECMWF ARE FAIRLY SIMILAR THROUGH THE EXTENDED WITH BROAD
HIGH PRESSURE ALOFT ACROSS THE CENTRAL STATES AND LOW PRESSURE
ACROSS EASTERN CANADA. APPEARS AT THIS TIME THAT THE HEAT WILL
REMAIN WEST OF THE AREA WITH MORE MODERATE/SEASONAL TEMPS FOR
SATURDAY AND SUNDAY. SUNDAY NIGHT THE GFS BRINGS ANOTHER SHOT OF
COOL AIR DOWN ACROSS THE LAKES AND THEN BOTH MODELS TEND TO DIG THE
UPPER LOW OVER CANADA SSE WITH THE UPPER HIGH DRIFTING WEST...WILL
BRING CHANCE POPS SUNDAY. MONDAY MORE HIGH PRESSURE WILL BUILD IN
FROM THE WEST WITH SEASONAL TO SLIGHTLY BELOW NORMAL TEMPS FOR THE
BEGINNING OF NEXT WEEK.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
WARM FRONT DIFFICULT TO PINPOINT BUT WINDS ACROSS THE AREA ARE
FROM THE SOUTHWEST AND DEWPOINTS ARE 65 TO 70 SO MAYBE A MOOT
POINT. CONVECTION ACROSS SRN LOWER MI HAVE BEEN AND WILL CONTINUE
TO TURN SOUTH TOWARD THE WESTERN PORTION OF THE CWA. TIMED THE
CONVECTION INTO TOL AT 1830Z. WILL CONTINUE IN TEMPO GROUP THRU
21Z. OTHERWISE...WITH PLENTY OF ENERGY ACROSS THE AREA FOLLOWED
HRRR GUIDANCE AND PUT VCTS IN TERMINALS FROM 20Z THROUGH 00Z. WILL
ALLOW FOR DIURNAL TRENDS TO DOMINATE AFTER 00Z SO WILL GO WITH A
COUPLE HOURS OF A VFR BROKEN CLOUD DECK THROUGH THE EVENING AS
DEBRIS FROM CONVECTION MOVES THROUGH FOLLOWED BY CLEARING SKIES
OVERNIGHT. GUIDANCE SUGGESTS SSW WINDS REMAIN AT 10KTS OVERNIGHT
BUT BELIEVE THEY WILL DROP INTO THE SINGLE DIGITS...AND WITH
MOISTURE IN PLACE EXPECT AT LEAST CENTRAL AND EASTERN TERMINALS
TO GO DOWN TO MVFR IN EARLY MORNING FOG.
.OUTLOOK...NON VFR POSSIBLE IN SCT CONVECTION ON THURSDAY.
&&
.MARINE...
CHOPPINESS OVER THE WESTERN PART OF THE LAKE FROM PASSING TSRA WILL
CALM DOWN DURING EARLY EVENING.
AS A WEAK WARM FRONT LIFTS NE ACROSS THE LAKE TONIGHT S WINDS WILL
INCREASE TO 10 TO 20 KNOTS AND BECOME SSW. WINDS OVER THE LAKE
SHOULD DIMINISH SOME FOR TUE AFTERNOON DURING THE HEAT OF THE DAY
DUE TO THE TEMP DIFFERENCE WITH THE LAKE. SW WINDS WILL GENERALLY
STAY UNDER 15 KNOTS INTO THU AS HIGH PRESSURE RIDGES NORTH INTO OHIO
FOR WED THEN SHIFTS EAST THU.
A COLD FRONT IS STILL ON TRACK TO MOVE SE ACROSS THE LAKE THU AND
WINDS VEER TO NW THEN N FOR FRI BUT WIND SPEEDS STAY FAIRLY LIGHT AS
HIGH PRESSURE QUICKLY BUILDS INTO THE LAKE. HIGH PRESSURE OVER THE
LAKE SAT SHOULD LEAD TO LIGHT AND VARIABLE WINDS.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...OUDEMAN
NEAR TERM...ABE/OUDEMAN
SHORT TERM...OUDEMAN
LONG TERM...TK
AVIATION...TK
MARINE...ADAMS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
147 AM EDT MON JUN 18 2012
.SYNOPSIS...
A WEAKENING COLD FRONT IS EXPECTED TO MOVE ACROSS NORTHERN OHIO
AND NW PA THIS THIS EVENING BEFORE STALLING OVER CENTRAL OHIO
TONIGHT. THE FRONT WILL DISSIPATE BY TUESDAY AS HIGH PRESSURE
STRENGTHENS OVER THE MIDDLE ATLANTIC. A STRONG HIGH WILL BE
OVERHEAD FOR MIDWEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
MUCH OF THE SHOWERS AND THUNDERSTORMS ARE OVER FAR NE OH AND NW PA
AS OF 02Z...HOWEVER THERE ARE SOME ISOLATED SHOWERS AND
THUNDERSTORMS ON RADAR STILL WHICH ARE EXPECTED TO PUSH EAST
ACROSS THE FORECAST AREA DURING THE OVERNIGHT. WILL CONTINUE WITH
ISOL-SCT POPS ESPECIALLY FOR THE EASTERN 2/3 OF THE FORECAST AREA
THROUGH THE OVERNIGHT. COVERAGE APPEARS TO BE LESS WITH ACTIVITY
DURING THE OVERNIGHT. RAISED TEMPS A FEW DEGREES ESPECIALLY ACROSS
EASTERN AREAS. PREVIOUS DISCUSSION BELOW.
TRIED TO TIME IT ACROSS THE AREA...LIKELY GETTING OUT OF NW PA
AROUND MIDNIGHT. HRRR DID WELL TIMING THIS INTO THE CLE METRO AREA
AND HAVE FOLLOWED CLOSELY TO THAT TO TIME IT ACROSS THE REST OF
THE AREA. WINDS WILL SHIFT TO THE WEST WITH THE PASSAGE OF THE
FRONT. LOWS IN THE 60S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY NIGHT/...
WHAT IS LEFT OF THE FRONT WILL GET A LITTLE PUSH NORTH MONDAY AND
HAVE CONTINUED A LOW CHANCE MENTION OF SHOWERS/TS. IT WILL BE
WARMER AGAIN...ESPECIALLY ACROSS THE WEST HALF WITH HIGHS GETTING
BACK INTO THE UPPER 80S. RIDGE REALLY BUILDS FOR MID WEEK AND
WILL GET BACK INTO THE 90S FOR MUCH OF THE AREA. HUMIDITY WILL BE
UP TOO...SO IT WILL FEEL UNCOMFORTABLE.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
MODELS IN AGREEMENT BREAKING DOWN MID WEEK UPPER RIDGE ACROSS THE
OHIO VALLEY AND BY THURSDAY IT SHOULD BE MOVING OFF THE MID ATLANTIC
COAST WITH A ZONAL FLOW DROPPING SOUTH ACROSS THE AREA. TO OUR
NORTH AN UPPER LOW WILL BE MOVING ACROSS HUDSON BAY AND THE SURFACE
SYSTEM WILL HAVE A TRAILING COLD FRONT THAT WILL MOVE THROUGH THE
AREA THURSDAY AFTERNOON. GLFMX MOISTURE APPEARS TO BE CLOSED OFF BY
HIGH PRESSURE ACROSS THE SOUTHEASTERN STATES SO SYSTEM SHOULD
HAVE LIMITED MOISTURE. STILL ENOUGH MOISTURE FOR TSTMS TO
ACCOMPANY THE FRONT SO WILL HAVE CHANCE POPS FOR THE AFTERNOON
THURSDAY INTO THURSDAY EVENING. FRIDAY THE FRONT WILL STALL OUT IN
THE LOWER OHIO VALLEY WITH A SURFACE HIGH ACROSS THE AREA. WILL
KEEP FORECAST DRY...SIDING MORE WITH THE ECMWF. SATURDAY MODELS
REDEVELOP AN UPPER RIDGE ACROSS THE NATIONS MID SECTION WITH A
NORTHWEST GRADIENT ALOFT ACROSS OHIO AND THE GREAT LAKES. A WARM
FRONT WILL BE STRENGTHENING ACROSS THE UPPER MIDWEST...AS THE
FRONT WHICH PASSED THROUGH THE AREA THURSDAY BEGINS TO MOVE
NORTHEAST. BOTH MODELS HINTING AT CONVECTION/SHORT WAVE MOVING
INTO THE AREA FROM ACROSS THE GREAT LAKES IN THE NORTHWEST FLOW.
WILL HAVE CHANCE POPS FOR NORTHEAST OHIO AND NORTHWEST PA SATURDAY
AND A SLIGHT CHANCE SUNDAY AS BY THEN THE VERY WARM AIR RETURNS
WITH THE BUILDING UPPER RIDGE.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
ONE LAST AREA OF SHOWERS AND WILL MOVE ACROSS KYNG THROUGH 07Z.
THERE MAYBE A RUMBLE OF THUNDER WITH IT. OTHERWISE WE WILL MONITOR
THE DEVELOPMENT OF FOG AND STRATOCU IN THE WAKE OF YESTERDAYS RAIN.
THE FOG AND MVFR CEILINGS WILL PERSIST UNTIL AFTER SUNRISE. THERE
WILL LIKELY BE PATCHES OF IFR CONDITIONS AROUND SUNRISE. WE WILL
THEN HAVE SIGNIFICANT AMOUNTS OF CONVECTIVE DEBRIS CLOUDINESS
THROUGH THE DAY. UNCERTAINTY AT THIS POINT WILL BE THE DEVELOPMENT
OF AFTERNOON THUNDERSTORMS. DO NOT FEEL CONFIDENT ENOUGH TO PLACE
THUNDERSTORMS IN THE TAF SITES AT THIS POINT.
.OUTLOOK...NON VFR POSSIBLE IN SCT CONVECTION MONDAY EVENING AND
AGAIN ON THURSDAY.
&&
.MARINE...
WEAK COLD FRONT WILL MOVE ACROSS THE LAKE THIS EVENING BRINGING
SHOWERS AND THUNDERSTORMS TO THE LAKE. THE FRONT WILL STALL OVER OR
JUST SOUTH OF THE LAKE OVERNIGHT BEFORE RETURNING AS A WARM FRONT
MONDAY. THIS WILL BRING ANOTHER CHANCE OF THUNDERSTORMS TO THE
LAKE. WINDS WILL BE FROM THE SOUTHWEST TONIGHT AT 10 TO 20 KNOTS
AND AGAIN MONDAY BEHIND THE WARM FRONT. TUESDAY THROUGH WEDNESDAY
WINDS WILL DIMINISH TO 10 KNOTS OF LESS MOST PLACES AS HIGH PRESSURE
BUILDS ACROSS THE LAKE FROM THE EAST. ANOTHER COLD FRONT WILL MOVE
ACROSS THE LAKE FROM THE NORTHWEST THURSDAY AND WILL BRING ANOTHER
CHANCE OF THUNDERSTORMS. WAVES WILL REMAIN BELOW 4 FEET THROUGH THE
PERIOD.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...OUDEMAN
NEAR TERM...ABE/OUDEMAN
SHORT TERM...OUDEMAN
LONG TERM...TK
AVIATION...MULLEN
MARINE...TK
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
549 PM EDT MON JUN 18 2012
.SYNOPSIS...
A WARM FRONT ENTRENCHED ALONG AND EAST OF THE ALLEGHENY MOUNTAINS
WILL LIFT SLOWLY NORTHWARD THROUGH TUESDAY. AN UPPER LEVEL RIDGE
BUILDING INTO THE MID-ATLANTIC STATES WILL BRING HOT AND HUMID
CONDITIONS THROUGH MID-WEEK. A COLD FRONT WILL MOVE THROUGH THE
AREA LATE THURSDAY OR EARLY FRIDAY...ALLOWING A COOLER AIR MASS TO
RETURN TO THE REGION THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
EAST OF A WARM FNT ENTRENCHED EAST OF THE ALLEGHENY FRONT...LOW
CLOUDS ARE STILL BLANKETING MUCH OF CENTRAL AND ERN PTNS OF THE
CWA PER 18Z VIS SATL IMAGERY. THIS WILL KEEP THE ATM STABLE OVER
THESE AREAS...WITH VERY LIMITED/ISOLATED PCPN EXPECTED THRU THE
REMAINDER OF THE PD. WILL LOWER POPS ACRS THIS AREA FOR THE REST
OF THE EVE.
THE LATEST VISIBLE SATL SHOWS AIRMASS OVR WRN PA /ALONG AND WEST
OF THE ALLEGHENIES/ IS BECOMING INCREASINGLY UNSTABLE...WITH
BREAKS IN THE CLOUDS ALLOWING FOR SUFFICIENT DESTABILIZATION FOR
SCT TSTM DEVELOPMENT. THE MAIN THREAT FOR TSTMS WILL GENERALLY BE
WEST OF JST-DUJ LINE...WITH HIGHEST POPS OVER THE LAUREL
HIGHLANDS. WEAK MID-LVL WINDS WILL LIMIT CONVECTIVE ORGANIZATION
AND STORMS HAVE EXHIBITED PULSE-TYPE CHARACTERISTICS...DRIVEN
LARGELY BY DIURNAL INSTABILITY. THEREFORE EXPECT MUCH OF THE
ACTIVITY TO WEAKEN INTO THE EVE HOURS WITH THE LOSS OF HEATING.
THE MESO MODEL DATA HAS DONE FAIRLY WELL THUS FAR IN DEPICTING
CONVECTIVE INITIATION AREA/COVERAGE. THE WILD CARD WILL BE UPSTREAM
MCS CROSSING XTRME SW LAKE ERIE. LATEST HRRR KEEPS THIS TSTM
COMPLEX OUT OF OUR CWA...WEAKENING THE SYSTEM AS IT DIVES SEWD
ACRS NERN OH THRU 00Z.
CLOUD COVER AND HIGH DEWPOINTS WILL KEEP MINS IN THE 60S IN MOST
PLACES OVERNIGHT.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
WARM FNT WILL LIFT SLOWLY NWD AS UPPER RIDGE BUILDS NEWD THRU THE
UPPER OH VLY. TEMPS WILL WARM ALOFT AND REACH +8-9C AT 700MB BY
00Z WED. LOW CLOUDS SHOULD GRADUALLY ERODE EARLY IN THE DAY...AND
MDL DATA SUGGESTS DIURNAL AIRMASS CONVECTION ACRS CENTRAL AND ERN
AREAS DURING PEAK HEATING. THE WARMING MID LEVEL TEMPS AND LIMITED
FORCING SHOULD ALLOW DIURNAL CONVECTION TO STAY MOSTLY ISOLATED
TO SCATTERED IN NATURE...AND MORE PROBABLE NEAR THE ELEVATED HEAT
SOURCES OF THE RIDGES/HIGHER MTN TERRAIN. INCREASING HEAT AND
HUMIDITY /SFC DEWPOINTS RISING WELL INTO 60S/ WILL RESULT IN HAZE
AND AREAS OF FOG OVERNIGHT TUES.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
WED/THU LOOK VERY WARM TO HOT WITH INCREASING HUMIDITIES. HEAT
INDICES LOOK TO NUDGE 100F OVER SERN ZONES FOR A TIME EACH
AFTERNOON...AND WILL LIKELY NEED A HEAT ADVISORY HEADLINE FOR
WED/THU AS EVENT GETS A LITTLE NEARER.
CONVECTION SHOULD CONTINUE TO BE MINIMIZED THANKS TO VERY WARM MID
LEVEL TEMPS WHICH ARE FCST TO REMAIN IN PLACE UNTIL LATER
THURSDAY...WHEN MED RANGE GUIDANCE SUGGESTS A NEW COLD FRONT
ENTERS THE PICTURE - INTRODUCING SCT TSTMS TO THE FORECAST.
THERE IS GOOD AGREEMENT IN A COOL DOWN TOWARD THE END OF THE WEEK
AS UPPER RIDGE TRANSITIONS TO AN ANOMALOUS UPPER TROF. THIS WILL
BRING CHANCES FOR RAIN AS SHORTWAVES RIPPLE DOWN THRU THE FLOW
INTO THE NORTHEAST STARTING FRIDAY. TIMING VERY DIFFICULT AT THIS
RANGE...SO MAINTAINED HEDGED TOWARD LOW POPS FOR MUCH OF THE
WEEKEND...THOUGH MODELS CONTINUING TO SLOWLY GAIN CONFIDENCE IN
POSSIBILITY OF A CHILLY RAIN FOR SAT NIGHT /NW/ AND SUNDAY /SE/.
&&
.AVIATION /22Z MONDAY THROUGH SATURDAY/...
VIS SATL SHOWS AIR MASS OVR WRN PA HAS DESTABILIZED ENOUGH TO
SUPPORT SCT TSTMS. RADAR LOOP SUGGESTS A BRIEF VSBY REDUCTION IS
POSSIBLE AT JST EARLY THIS EVENING. OTHERWISE...MAIN AVIATION
CONCERN OVERNIGHT WILL BE THE POTENTIAL OF LOW CIGS ACROSS THE
CENTRAL MTNS.
LOW CLOUDS /LOW END MVFR CIGS 1-2KFT AGL/ CONTINUE TO BLANKET
MUCH OF CNTRL AND ERN PA AS OF 21Z. XPECT CIGS TO LOWER OVERNIGHT
WITH LOW MVFR TO IFR CIGS AT MOST TAF SITES. SREF OUTPUT AND
LATEST 18Z MDL GUIDANCE BOTH SUGGEST THE CENTRAL MTNS SHOULD SEE
THE LOWEST CIGS...THE RESULT OF MOIST SERLY FLOW ASCENDING THE
HIGHER TERRAIN. IMPROVEMENT IS EXPECTED LATE TUE AM...AS WARM
FRONT PUSHES NORTH OF THE AREA...BRINGING CLEARING SKIES. ISOLD
TSRA COULD DEVELOP ALONG THE SPINE OF THE APPALACHIANS DURING THE
AFTN. HOWEVER...MOST AIRFIELDS SHOULD BE UNAFFECTED.
OUTLOOK...
TUE...AM FOG-HZ/LOW CIGS POSS. ISOLD PM TSTM IMPACTS POSS.
WED...AM FOG POSSIBLE.
THU...ISOLD PM TSTM IMPACTS POSS.
FRI...NO SIG WX EXPECTED.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...RXR
AVIATION...FITZGERALD/STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
328 PM EDT MON JUN 18 2012
.SYNOPSIS...
A WARM FRONT ENTRENCHED ALONG AND EAST OF THE ALLEGHENY MOUNTAINS
WILL LIFT SLOWLY NORTHWARD THROUGH TUESDAY. AN UPPER LEVEL RIDGE
BUILDING INTO THE MID-ATLANTIC STATES WILL BRING HOT AND HUMID
CONDITIONS THROUGH MID-WEEK. A COLD FRONT WILL MOVE THROUGH THE
AREA LATE THURSDAY OR EARLY FRIDAY...ALLOWING A COOLER AIRMASS TO
RETURN TO THE REGION THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
EAST OF A WARM FNT ENTRENCHED EAST OF THE ALLEGHENY FRONT...LOW
CLOUDS ARE STILL BLANKETING MUCH OF CENTRAL AND ERN PTNS OF THE
CWA PER 18Z VIS SATL IMAGERY. THIS WILL KEEP THE ATM STABLE OVER
THESE AREAS...WITH VERY LIMITED/ISOLATED PCPN EXPECTED THRU THE
REMAINDER OF THE PD. WILL LOWER POPS ACRS THIS AREA FOR THE REST
OF THE EVE.
THE LATEST VISIBLE SATL SHOWS AIRMASS OVR WRN PA /ALONG AND WEST
OF THE ALLEGHENIES/ IS BECOMING INCREASINGLY UNSTABLE...WITH
BREAKS IN THE CLOUDS ALLOWING FOR SUFFICIENT DESTABILIZATION FOR
SCT TSTM DEVELOPMENT. THE MAIN THREAT FOR TSTMS WILL GENERALLY BE
WEST OF JST-DUJ LINE...WITH HIGHEST POPS OVER THE LAUREL
HIGHLANDS. WEAK MID-LVL WINDS WILL LIMIT CONVECTIVE ORGANIZATION
AND STORMS HAVE EXHIBITED PULSE-TYPE CHARACTERISTICS...DRIVEN
LARGELY BY DIURNAL INSTABILITY. THEREFORE EXPECT MUCH OF THE
ACTIVITY TO WEAKEN INTO THE EVE HOURS WITH THE LOSS OF HEATING.
THE MESO MODEL DATA HAS DONE FAIRLY WELL THUS FAR IN DEPICTING
CONVECTIVE INITIATION AREA/COVERAGE. THE WILD CARD WILL BE UPSTREAM
MCS CROSSING XTRME SW LAKE ERIE. LATEST HRRR KEEPS THIS TSTM
COMPLEX OUT OF OUR CWA...WEAKENING THE SYSTEM AS IT DIVES SEWD
ACRS NERN OH THRU 00Z.
CLOUD COVER AND HIGH DEWPOINTS WILL KEEP MINS IN THE 60S IN MOST
PLACES OVERNIGHT.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
WARM FNT WILL LIFT SLOWLY NWD AS UPPER RIDGE BUILDS NEWD THRU THE
UPPER OH VLY. TEMPS WILL WARM ALOFT AND REACH +8-9C AT 700MB BY
00Z WED. LOW CLOUDS SHOULD GRADUALLY ERODE EARLY IN THE DAY...AND
MDL DATA SUGGESTS DIURNAL AIRMASS CONVECTION ACRS CENTRAL AND ERN
AREAS DURING PEAK HEATING. THE WARMING MID LEVEL TEMPS AND LIMITED
FORCING SHOULD ALLOW DIURNAL CONVECTION TO STAY MOSTLY ISOLATED
TO SCATTERED IN NATURE...AND MORE PROBABLE NEAR THE ELEVATED HEAT
SOURCES OF THE RIDGES/HIGHER MTN TERRAIN. INCREASING HEAT AND
HUMIDITY /SFC DEWPOINTS RISING WELL INTO 60S/ WILL RESULT IN HAZE
AND AREAS OF FOG OVERNIGHT TUES.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
WED/THU LOOK VERY WARM TO HOT WITH INCREASING HUMIDITIES. HEAT
INDICES LOOK TO NUDGE 100F OVER SERN ZONES FOR A TIME EACH
AFTERNOON...AND WILL LIKELY NEED A HEAT ADVISORY HEADLINE FOR
WED/THU AS EVENT GETS A LITTLE NEARER.
CONVECTION SHOULD CONTINUE TO BE MINIMIZED THANKS TO VERY WARM MID
LEVEL TEMPS WHICH ARE FCST TO REMAIN IN PLACE UNTIL LATER
THURSDAY...WHEN MED RANGE GUIDANCE SUGGESTS A NEW COLD FRONT
ENTERS THE PICTURE - INTRODUCING SCT TSTMS TO THE FORECAST.
THERE IS GOOD AGREEMENT IN A COOL DOWN TOWARD THE END OF THE WEEK
AS UPPER RIDGE TRANSITIONS TO AN ANOMALOUS UPPER TROF. THIS WILL
BRING CHANCES FOR RAIN AS SHORTWAVES RIPPLE DOWN THRU THE FLOW
INTO THE NORTHEAST STARTING FRIDAY. TIMING VERY DIFFICULT AT THIS
RANGE...SO MAINTAINED HEDGED TOWARD LOW POPS FOR MUCH OF THE
WEEKEND...THOUGH MODELS CONTINUING TO SLOWLY GAIN CONFIDENCE IN
POSSIBILITY OF A CHILLY RAIN FOR SAT NIGHT /NW/ AND SUNDAY /SE/.
&&
.AVIATION /19Z MONDAY THROUGH SATURDAY/...
VIS SATL SHOWS AIRMASS OVR WRN PA HAS DESTABILIZED ENOUGH TO
SUPPORT ISOLD TO SCT TSTMS. HAVE INDICATED VCSH/VCTS AT BFD AND
JST BUT POINT PROBS ARE LOW.
LOW CLOUDS /LOW END MVFR CIGS 1-2KFT AGL/ WILL CONTINUE TO BLANKET
MUCH OF CNTRL AND ERN PA THRU THIS EVE. XPECT CIGS TO LOWER
OVERNIGHT WITH LOW MVFR TO IFR CIGS MAINTAINED AT MOST TAF SITES.
SLOW IMPROVEMENT WILL OCCUR EARLY TOMORROW WITH CONDS EVENTUALLY
BCMG VFR BY LATER TUE AFTN.
OUTLOOK...
TUE...AM FOG-HZ/LOW CIGS POSS. ISOLD PM TSTM IMPACTS POSS.
WED...AM FOG POSSIBLE.
THU...ISOLD PM TSTM IMPACTS POSS.
FRI...NO SIG WX EXPECTED.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...RXR
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
254 PM EDT MON JUN 18 2012
.SYNOPSIS...
A WARM FRONT ENTRENCHED ALONG AND EAST OF THE ALLEGHENY MOUNTAINS
WILL LIFT SLOWLY NORTHWARD THROUGH TUESDAY. AN UPPER LEVEL RIDGE
BUILDING INTO THE MID-ATLANTIC STATES WILL BRING HOT AND HUMID
CONDITIONS THROUGH MID-WEEK. A COLD FRONT WILL MOVE THROUGH THE
AREA LATE THURSDAY OR EARLY FRIDAY...ALLOWING A COOLER AIRMASS TO
RETURN TO THE REGION THIS WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
EAST OF A WARM FNT ENTRENCHED EAST OF THE ALLEGHENY FRONT...LOW
CLOUDS ARE STILL BLANKETING MUCH OF CENTRAL AND ERN PTNS OF THE
CWA PER 18Z VIS SATL IMAGERY. THIS WILL KEEP THE ATM STABLE OVER
THESE AREAS...WITH VERY LIMITED/ISOLATED PCPN EXPECTED THRU THE
REMAINDER OF THE PD. WILL LOWER POPS ACRS THIS AREA FOR THE REST
OF THE EVE.
THE LATEST VISIBLE SATL SHOWS AIRMASS OVR WRN PA /ALONG AND WEST
OF THE ALLEGHENIES/ IS BECOMING INCREASINGLY UNSTABLE...WITH
BREAKS IN THE CLOUDS ALLOWING FOR SUFFICIENT DESTABILIZATION FOR
SCT TSTM DEVELOPMENT. THE MAIN THREAT FOR TSTMS WILL GENERALLY BE
WEST OF JST-DUJ LINE...WITH HIGHEST POPS OVER THE LAUREL
HIGHLANDS. WEAK MID-LVL WINDS WILL LIMIT CONVECTIVE ORGANIZATION
AND STORMS HAVE EXHIBITED PULSE-TYPE CHARACTERISTICS...DRIVEN
LARGELY BY DIURNAL INSTABILITY. THEREFORE EXPECT MUCH OF THE
ACTIVITY TO WEAKEN INTO THE EVE HOURS WITH THE LOSS OF HEATING.
THE MESO MODEL DATA HAS DONE FAIRLY WELL THUS FAR IN DEPICTING
CONVECTIVE INITIATION AREA/COVERAGE. THE WILD CARD WILL BE UPSTREAM
MCS CROSSING XTRME SW LAKE ERIE. LATEST HRRR KEEPS THIS TSTM
COMPLEX OUT OF OUR CWA...WEAKENING THE SYSTEM AS IT DIVES SEWD
ACRS NERN OH THRU 00Z.
CLOUD COVER AND HIGH DEWPOINTS WILL KEEP MINS IN THE 60S IN MOST
PLACES OVERNIGHT.
&&
.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
WARM FNT WILL LIFT SLOWLY NWD AS UPPER RIDGE BUILDS NEWD THRU THE
UPPER OH VLY. TEMPS WILL WARM ALOFT AND REACH +8-9C AT 700MB BY
00Z WED. LOW CLOUDS SHOULD GRADUALLY ERODE EARLY IN THE DAY...AND
MDL DATA SUGGESTS DIURNAL AIRMASS CONVECTION ACRS CENTRAL AND ERN
AREAS DURING PEAK HEATING. THE WARMING MID LEVEL TEMPS AND LIMITED
FORCING SHOULD ALLOW DIURNAL CONVECTION TO STAY MOSTLY ISOLATED
TO SCATTERED IN NATURE...AND MORE PROBABLE NEAR THE ELEVATED HEAT
SOURCES OF THE RIDGES/HIGHER MTN TERRAIN. INCREASING HEAT AND
HUMIDITY /SFC DEWPOINTS RISING WELL INTO 60S/ WILL RESULT IN HAZE
AND AREAS OF FOG OVERNIGHT TUES.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
WED/THU LOOK VERY WARM TO HOT AND QUITE MUGGY. HEAT INDICES COULD
NUDGE 100 OVER SERN ZONES FOR A TIME EACH AFTERNOON...BUT
WIDESPREAD EXCESSIVE HEAT INDICES ARE NOT YET INDICATED. IF TEMPS
OR DEWPOINTS GET NUDGED UP A BIT HOWEVER...WE COULD BE DEALING
WITH THE SEASON`S FIRST HEATWAVE AND ADVISORY HEADLINES.
CONVECTION SHOULD CONTINUE TO BE MINIMIZED THANKS TO VERY WARM MID
LEVEL TEMPS WHICH ARE FCST TO REMAIN IN PLACE UNTIL LATER THURSDAY
WHEN MED RANGE GUIDANCE SUGGESTS A NEW COLD FRONT ENTERS THE
PICTURE.
THERE IS GOOD AGREEMENT IN A COOL DOWN TOWARD THE END OF THE WEEK
AS OUR UPPER RIDGE TRANSITIONS TO AN ANOMALOUS UPPER TROF. THIS
WILL BRING CHANCES FOR RAIN AS SHORTWAVES RIPPLE DOWN THRU THE
FLOW INTO THE NORTHEAST STARTING FRIDAY. TIMING AT THIS RANGE IS
IMPOSSIBLE SO HEDGED TOWARD LOW POPS FOR MUCH OF THE WEEKEND.
INTERESTING ECMWF DEVELOPMENT WOULD GIVE US A WIDESPREAD CHILLY
RAIN FOR SUNDAY. STILL FAR OUT IN THE EXTENDED...BUT THE PATTERN
IT IS PAINTING LOOKS LIKE ANYTHING BUT THE FIRST DAYS OF THE
ASTRONOMICAL SUMMER.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
VIS SATL SHOWS AIRMASS OVR WRN PA HAS DESTABILIZED ENOUGH TO
SUPPORT ISOLD TO SCT TSTMS. HAVE INDICATED VCSH/VCTS AT BFD AND
JST BUT POINT PROBS ARE LOW.
LOW CLOUDS /LOW END MVFR CIGS 1-2KFT AGL/ WILL CONTINUE TO BLANKET
MUCH OF CNTRL AND ERN PA THRU THIS EVE. XPECT CIGS TO LOWER
OVERNIGHT WITH LOW MVFR TO IFR CIGS MAINTAINED AT MOST TAF SITES.
SLOW IMPROVEMENT WILL OCCUR EARLY TOMORROW WITH CONDS EVENTUALLY
BCMG VFR BY LATER TUE AFTN.
OUTLOOK...
TUE...AM FOG-HZ/LOW CIGS POSS. ISOLD PM TSTM IMPACTS POSS.
WED...AM FOG POSSIBLE.
THU...ISOLD PM TSTM IMPACTS POSS.
FRI...NO SIG WX EXPECTED.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...LA CORTE
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1006 AM EDT MON JUN 18 2012
.SYNOPSIS...
A WEAKENING COLD FRONT WILL BRING A FEW SHOWERS AND THUNDERSTORMS
TO THE REGION TODAY BEFORE MUCH WARMER AND MORE HUMID AIR MOVES
INTO THE COMMONWEALTH FOR MUCH OF THE UPCOMING WEEK. COOLER AND
DRIER AIR WILL ARRIVE IN TIME FOR THE WEEKEND AS A DEEP TROUGH
MOVES ACROSS THE NORTHEAST STATES.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
RADAR LOOP SHOWS BAND OF SHOWERS WEAKENING OVR THE LWR SUSQ VLY.
THIS AREA OF -RA SHOULD EXIT THE SE ZONES BY 15-16Z. MUCH OF THE
AREA WILL BE CLOUDY BUT DRY THRU LATE MORNING. BINOVC SHOULD LEAD
TO DIURNAL INSTABILITY OVR WRN PA WITH ISOLD-SCT CONVECTION
DEVELOPING WEST OF THE LAURELS BY EARLY AFTN.
PREVIOUS DISCUSSION ISSUED 805 AM...BAND OF LIGHT RAIN/SHOWERS MOVG
INTO THE SUSQ VLY AT 12Z. PCPN IS MORE SCATTERED IN NATURE ACROSS
THE WESTERN HALF OF THE CWA. THE MAIN PCPN BAND IS ASSOC WITH A
STRIPE OF 850MB THETA-E/MSTR CONVERGENCE ALONG WEAKENING FRONT/SFC
DEWPT GRADIENT. HIGH RES MDL DATA SHOWS THIS AREA OF LIGHT QPF
CONTINUING TO WEAKEN AS IT SHIFTS EWD TWD THE ERN EDGE OF THE CWA
BY 15Z.
SELY UPSLOPE FLOW SHOULD KEEP PLENTY OF LOW CLOUDS LOCKED IN OVR
THE ERN HALF OF THE CWA THRU MUCH OF THE DAY. THIS WILL KEEP THE
ATM STABLE. SREF DATA SHOWS THE INSTABILITY AXIS CONFINED ALONG
AND WEST OF THE ALLEGHENY FRONT...AND HI RES HRRR DEVELOPS SCT
AIRMASS TYPE SHOWERS AND TSTMS OVR WRN PA BY 18Z. MID-UPPER
FORCING REMAINS VERY WEAK AND HEIGHTS WILL RISE THROUGH THE
EVE...AS UPPER RIDGE BEGINS TO BUILD NWD FM THE OH RVR VLY. THERE
ARE A FEW SUBTLE SHORTWAVES MOVG THRU ALOFT BUT OVERALL XPECT
ANY DIURNAL CONVECTIVE ACTIVITY TO DECREASE IN CVRG/DISSIPATE
AFTER DARK.
HIGHS TODAY WILL BE NOTICEABLY COOLER THAN PREV DAYS...ONLY IN
THE LOW TO MID 70S IN MOST AREAS. SOME AREAS MAY NOT GET ABV 70F.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH 6 PM TUESDAY/...
AS THE MID LEVEL RIDGE BUILDS STRONGLY INTO THE AREA TONIGHT AND
TUESDAY...PRECIP SHUD BECOME MORE SCARCE. BIGGEST ISSUE IS HOW
MUCH IF ANY DIURNAL CONVECTION WE SEE FIRE UP TUESDAY. OPERATIONAL
GFS HAS VERY WARM MID LEVEL TEMPS SURGING INTO THE REGION WHICH
USUALLY ACT AS AN EFFECTIVE CAP TO CONVECTION. THE NAM IS LESS
WARM ALOFT ALLOWING FOR MORE DIURNAL DEVELOPMENT. SREF/GEFS SHOW
THE POTENTIAL FOR SCATTERED AFTERNOON SHOWERS AND STORMS SO HAVE
INCLUDED A SMALL CHANCE AND MAINLY CONFINED THEM TO HIGHER
ELEVATIONS OF THE WEST. WITH SUCH A STRONG RIDGE ALOFT I STILL
HAVE A HARD TIME WE WILL BE ABLE TO REALIZE MUCH ACTION
DEVELOPING.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
WED/THU LOOK VERY WARM TO HOT AND QUITE MUGGY. HEAT INDICES COULD
NUDGE 100 OVER SERN ZONES FOR A TIME EACH AFTERNOON...BUT
WIDESPREAD EXCESSIVE HEAT INDICES ARE NOT YET INDICATED. IF TEMPS
OR DEWPOINTS GET NUDGED UP A BIT HOWEVER...WE COULD BE DEALING
WITH THE SEASON`S FIRST HEATWAVE AND ADVISORY HEADLINES.
CONVECTION SHOULD CONTINUE TO BE MINIMIZED THANKS TO VERY WARM MID
LEVEL TEMPS WHICH ARE FCST TO REMAIN IN PLACE UNTIL LATER THURSDAY
WHEN MED RANGE GUIDANCE SUGGESTS A NEW COLD FRONT ENTERS THE
PICTURE.
THERE IS GOOD AGREEMENT IN A COOL DOWN TOWARD THE END OF THE WEEK
AS OUR UPPER RIDGE TRANSITIONS TO AN ANOMALOUS UPPER TROF. THIS
WILL BRING CHANCES FOR RAIN AS SHORTWAVES RIPPLE DOWN THRU THE
FLOW INTO THE NORTHEAST STARTING FRIDAY. TIMING AT THIS RANGE IS
IMPOSSIBLE SO HEDGED TOWARD LOW POPS FOR MUCH OF THE WEEKEND.
INTERESTING ECMWF DEVELOPMENT WOULD GIVE US A WIDESPREAD CHILLY
RAIN FOR SUNDAY. STILL FAR OUT IN THE EXTENDED...BUT THE PATTERN
IT IS PAINTING LOOKS LIKE ANYTHING BUT THE FIRST DAYS OF THE
ASTRONOMICAL SUMMER.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
SEVERAL MORE HOURS OF SHOWERS. MADE SOME ADJUSTMENTS TO
CURRENT FCST PACKAGE.
BEEN WATCHING CONVECTION OVER SOUTHERN OH...ACTIVITY NOW
LOOKS LIKE IT WOULD STAY SOUTH OF ANY OF OUR TAF LOCATIONS.
ADDED IN SOME FOG FOR TONIGHT...DEWPOINTS WILL BE HIGHER...
BUT WINDS MAY LIMIT FOG FORMATION.
EARLIER DISCUSSION BELOW.
BEEN WATCHING THE SHOWERS AND STORMS ON THE RADAR SINCE I CAME
IN AT MIDNIGHT. AIRMASS EAST OF THE MOUNTAINS NOT REAL WARM OR
HUMID...SO ACTIVITY HAS BEEN SLOW TO MOVE INTO THE AREA. STRONGEST
ACTIVITY FORMING ON THE WESTERN EDGE OF THE AREA OF SHOWERS AND
STORMS...WHERE THE AIRMASS IS MORE UNSTABLE.
VERY WINDY JUST BEFORE MIDNIGHT AT IPT. ALSO INTERESTING THAT
EACH DAY OF THE LAST 3 DAYS IS COOLER THAN THE ONE BEFORE IT.
ANYWAY...EXPECT SOME IMPROVEMENT TO CONDITIONS LATER THIS
AFTERNOON...BEFORE CIGS AND VISIBILITIES DROP AGAIN AFTER
DARK.
MUCH OF THE PERIOD TUE INTO THU SHOULD BE DRY...MAINLY VFR...AND
ON THE HOT AND HUMID SIDE...AS HIGH PRESSURE SFC AND ALOFT BUILDS
INTO THE AREA.
COLD FRONT FOR LATE THU...STRONG TO EVEN SEVERE STORMS
WILL BE POSSIBLE.
LATE FRIDAY INTO THE WEEKEND NOT SO CLEAR CUT...PATTERN CHANGES
BACK TO HAVING A TROUGH ACROSS THE NE. NORMALLY WOULD EXPECT
COOLER TEMPS. IN THIS CASE...A LOT OF VARIATION...COULD SEE A
SECONDARY FRONT DROPPING SE WITH SOME SHOWERS AND EVEN A
THUNDERSTORM AT SOME POINT.
OUTLOOK...
TUE...AM FOG-HZ/LOW CIGS POSS. ISOLD PM TSTM IMPACTS POSS.
WED...AM FOG POSSIBLE.
THU...ISOLD PM TSTM IMPACTS POSS.
FRI...NO SIG WX EXPECTED.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...STEINBUGL
SHORT TERM...LA CORTE
LONG TERM...LA CORTE
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
805 AM EDT MON JUN 18 2012
.SYNOPSIS...
A WEAKENING COLD FRONT WILL BRING A FEW SHOWERS AND THUNDERSTORMS
TO THE REGION TODAY BEFORE MUCH WARMER AND MORE HUMID AIR MOVES
INTO THE COMMONWEALTH FOR MUCH OF THE UPCOMING WEEK. COOLER AND
DRIER AIR WILL ARRIVE IN TIME FOR THE WEEKEND AS A DEEP TROUGH
MOVES ACROSS THE NORTHEASTERN US.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
BAND OF LIGHT RAIN/SHOWERS MOVG INTO THE SUSQ VLY AT 12Z. PCPN IS
MORE SCATTERED IN NATURE ACROSS THE WESTERN HALF OF THE CWA. THE
MAIN PCPN BAND IS ASSOC WITH A STRIPE OF 850MB THETA-E/MSTR
CONVERGENCE ALONG WEAKENING FRONT/SFC DEWPT GRADIENT. HIGH RES MDL
DATA SHOWS THIS AREA OF LIGHT QPF CONTINUING TO WEAKEN AS IT
SHIFTS EWD TWD THE ERN EDGE OF THE CWA BY 15Z.
SELY UPSLOPE FLOW SHOULD KEEP PLENTY OF LOW CLOUDS LOCKED IN OVR
THE ERN HALF OF THE CWA THRU MUCH OF THE DAY. THIS WILL KEEP THE
ATM STABLE. SREF DATA SHOWS THE INSTABILITY AXIS CONFINED ALONG
AND WEST OF THE ALLEGHENY FRONT...AND HI RES HRRR DEVELOPS SCT
AIRMASS TYPE SHOWERS AND TSTMS OVR WRN PA BY 18Z. MID-UPPER
FORCING REMAINS VERY WEAK AND HEIGHTS WILL RISE THROUGH THE
EVE...AS UPPER RIDGE BEGINS TO BUILD NWD FM THE OH RVR VLY. THERE
ARE A FEW SUBTLE SHORTWAVES MOVG THRU ALOFT BUT OVERALL XPECT
ANY DIURNAL CONVECTIVE ACTIVITY TO DECREASE IN CVRG/DISSIPATE
AFTER DARK.
HIGHS TODAY WILL BE NOTICEABLY COOLER THAN PREV DAYS...ONLY IN
THE LOW TO MID 70S IN MOST AREAS. SOME AREAS MAY NOT GET ABV 70F.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH 6 PM TUESDAY/...
AS THE MID LEVEL RIDGE BUILDS STRONGLY INTO THE AREA TONIGHT AND
TUESDAY...PRECIP SHUD BECOME MORE SCARCE. BIGGEST ISSUE IS HOW
MUCH IF ANY DIURNAL CONVECTION WE SEE FIRE UP TUESDAY. OPERATIONAL
GFS HAS VERY WARM MID LEVEL TEMPS SURGING INTO THE REGION WHICH
USUALLY ACT AS AN EFFECTIVE CAP TO CONVECTION. THE NAM IS LESS
WARM ALOFT ALLOWING FOR MORE DIURNAL DEVELOPMENT. SREF/GEFS SHOW
THE POTENTIAL FOR SCATTERED AFTERNOON SHOWERS AND STORMS SO HAVE
INCLUDED A SMALL CHANCE AND MAINLY CONFINED THEM TO HIGHER
ELEVATIONS OF THE WEST. WITH SUCH A STRONG RIDGE ALOFT I STILL
HAVE A HARD TIME WE WILL BE ABLE TO REALIZE MUCH ACTION
DEVELOPING.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
WED/THU LOOK VERY WARM TO HOT AND QUITE MUGGY. HEAT INDICES COULD
NUDGE 100 OVER SERN ZONES FOR A TIME EACH AFTERNOON...BUT
WIDESPREAD EXCESSIVE HEAT INDICES ARE NOT YET INDICATED. IF TEMPS
OR DEWPOINTS GET NUDGED UP A BIT HOWEVER...WE COULD BE DEALING
WITH THE SEASON`S FIRST HEATWAVE AND ADVISORY HEADLINES.
CONVECTION SHOULD CONTINUE TO BE MINIMIZED THANKS TO VERY WARM MID
LEVEL TEMPS WHICH ARE FCST TO REMAIN IN PLACE UNTIL LATER THURSDAY
WHEN MED RANGE GUIDANCE SUGGESTS A NEW COLD FRONT ENTERS THE
PICTURE.
THERE IS GOOD AGREEMENT IN A COOL DOWN TOWARD THE END OF THE WEEK
AS OUR UPPER RIDGE TRANSITIONS TO AN ANOMALOUS UPPER TROF. THIS
WILL BRING CHANCES FOR RAIN AS SHORTWAVES RIPPLE DOWN THRU THE
FLOW INTO THE NORTHEAST STARTING FRIDAY. TIMING AT THIS RANGE IS
IMPOSSIBLE SO HEDGED TOWARD LOW POPS FOR MUCH OF THE WEEKEND.
INTERESTING ECMWF DEVELOPMENT WOULD GIVE US A WIDESPREAD CHILLY
RAIN FOR SUNDAY. STILL FAR OUT IN THE EXTENDED...BUT THE PATTERN
IT IS PAINTING LOOKS LIKE ANYTHING BUT THE FIRST DAYS OF THE
ASTRONOMICAL SUMMER.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
SEVERAL MORE HOURS OF SHOWERS. MADE SOME ADJUSTMENTS TO
CURRENT FCST PACKAGE.
BEEN WATCHING CONVECTION OVER SOUTHERN OH...ACTIVITY NOW
LOOKS LIKE IT WOULD STAY SOUTH OF ANY OF OUR TAF LOCATIONS.
ADDED IN SOME FOG FOR TONIGHT...DEWPOINTS WILL BE HIGHER...
BUT WINDS MAY LIMIT FOG FORMATION.
EARLIER DISCUSSION BELOW.
BEEN WATCHING THE SHOWERS AND STORMS ON THE RADAR SINCE I CAME
IN AT MIDNIGHT. AIRMASS EAST OF THE MOUNTAINS NOT REAL WARM OR
HUMID...SO ACTIVITY HAS BEEN SLOW TO MOVE INTO THE AREA. STRONGEST
ACTIVITY FORMING ON THE WESTERN EDGE OF THE AREA OF SHOWERS AND
STORMS...WHERE THE AIRMASS IS MORE UNSTABLE.
VERY WINDY JUST BEFORE MIDNIGHT AT IPT. ALSO INTERESTING THAT
EACH DAY OF THE LAST 3 DAYS IS COOLER THAN THE ONE BEFORE IT.
ANYWAY...EXPECT SOME IMPROVEMENT TO CONDITIONS LATER THIS
AFTERNOON...BEFORE CIGS AND VISIBILITIES DROP AGAIN AFTER
DARK.
MUCH OF THE PERIOD TUE INTO THU SHOULD BE DRY...MAINLY VFR...AND
ON THE HOT AND HUMID SIDE...AS HIGH PRESSURE SFC AND ALOFT BUILDS
INTO THE AREA.
COLD FRONT FOR LATE THU...STRONG TO EVEN SEVERE STORMS
WILL BE POSSIBLE.
LATE FRIDAY INTO THE WEEKEND NOT SO CLEAR CUT...PATTERN CHANGES
BACK TO HAVING A TROUGH ACROSS THE NE. NORMALLY WOULD EXPECT
COOLER TEMPS. IN THIS CASE...A LOT OF VARIATION...COULD SEE A
SECONDARY FRONT DROPPING SE WITH SOME SHOWERS AND EVEN A
THUNDERSTORM AT SOME POINT.
OUTLOOK...
TUE...AM FOG-HZ/LOW CIGS POSS. ISOLD PM TSTM IMPACTS POSS.
WED...AM FOG POSSIBLE.
THU...ISOLD PM TSTM IMPACTS POSS.
FRI...NO SIG WX EXPECTED.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE/STEINBUGL
SHORT TERM...LA CORTE
LONG TERM...LA CORTE
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
152 PM EDT MON JUN 18 2012
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL PERSIST OVER THE REGION THROUGH THE
WEEK...BRINGING ABOVE AVERAGE TEMPS. A WEAK COLD FRONT WILL THEN
APPROACH THE CWA FROM THE NW ON FRIDAY AND SATURDAY.
&&
.NEAR TERM /THROUGH TUESDAY/...
AS OF 145 PM EDT...WIDELY SCATTERED CONVECTION IS INDICATED BY
RADAR ALONG THE BLUE RIDGE AS EXPECTED. EXPECT THAT CONVECTIVE
ACTIVITY WILL INCREASE SOME IN COVERAGE PER THE LATEST HRRR INTO THE
SCATTERED CATEGORY...BUT REMAIN CONFINED TO THE MOUNTAINS. UPDRAFTS
DO NOT LOOK PARTICUALRY STRONG AND WITH WEAK WIND FIELDS...THE
THREAT OF SEVERE IS MINIMAL. IT WILL TAKE A 55DBZ CORE TO NEAR 24KFT
FOR SEVERE HAIL TODAY. CURRENT REGIONAL RADARS SHOW MORE ORGANIZED
CONVECTION WELL TO THE NE IN VA ASSOCIATED WITH SOME APPARENT WEAK
MCV`S. EXPANDING THE SCATTERED TYPE POPS OUT INTO THE NC FOOTHILLS
AND NC NORTHERN PIEDMONT THIS AFTERNOON STILL APPEARS PRUDENT AS
THIS AREA IS SKIRTED BY SOME WEAK UPPER FORCING.
THE UPPER RIDGE INITIALLY TO THE WEST IS FORECAST TO DEVELOP INTO
A CLOSED UPPER HIGH OVER THE OHIO VALLEY ON TUE WITH SURFACE HIGH
PRESSURE OVER THE WESTERN ATLANTIC. A WEAK SW WIND FLOW WILL REMAIN
OVER THE REGION ALONG WITH VERY WARM TEMPS. THE 12Z NAM FORECASTS
A MCV TO MOVE FROM VA INTO CENTRAL NC OVERNIGHT. LOOKS LIKE
MOST...IF NOT ALL OF THE CONVECTION SHOULD MISS THE CWA...SO JUST
ISOLATED POPS IN THE NORTHERN NC FOOTHILLS/PIEDMONT.
ON TUESDAY...THE WEAK BUT SOMEWHAT UPSLOPE FLOW SHOULD BE ENOUGH TO
GENERATE WIDELY SCATTERED/SCATTERED CONVECTION AGAIN OVER THE
MOUNTAINS DURING THE AFTERNOON. MAX TEMPS WILL PROBABLY HIT 90
ACROSS THE SOUTHERN UPSTATE WITH UPPER 80S ELSEHWERE OUTSIDE THE
MOUNTAINS. THE MOUNTAIN VALLEYS WILL BE QUITE WARM AS WELL WITH
LOWER TO MIDDLE 80S THERE.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
AS OF 115 PM SUNDAY...A DEEP LAYER RIDGE OF HIGH PRESSURE WILL DRIFT
NORTHWARD...ACROSS THE MID-ATLANTIC STATES DURING THE DAY ON
THURSDAY. THIS WILL PUT THE FA UNDER A LIGHT E TO SE FLOW. MODEL
SOUNDINGS SHOW A MODEST AMOUNT OF CONVECTIVE INHIBITION OVER THE
FOOTHILLS AND PIEDMONT. THE MOUNTAINS LOOK A LITTLE MORE UNSTABLE
THOUGH LAPSE RATES WILL NOT BE STEEP. ANY SHOWERS AND STORMS THAT
DEVELOP SHOULD DRIFT TO THE NORTHWEST...TOWARD ERN TN.
THEREFORE...I/M KEEPING POPS QUITE LOW IN THE FOOTHILLS AND
PIEDMONT...WITH SLIGHT CHANCE TO LOW END CHANCE POPS OVER THE HIGH
TERRAIN. TEMPS WILL BE A FEW DEGREES ABOVE NORMAL...THOUGH WITH THE
ESE FLOW I DON/T SEE FOOTHILL AND PIEDMONT LOCATIONS GETTING MUCH
HOTTER THAN 90 OR 91 DEGREES.
THE RIDGE WILL WEAKEN AND DROP TO THE SOUTH OF THURSDAY...TURNING
THE FLOW FROM LIGHT EASTERLY TO VERY LIGHT WESTERLY ACROSS THE FA.
THE GFS HAS A LITTLE HIGHER DEWPOINT POOLING ALONG THE LEE...BUT
WARM MID LEVELS STILL WORK TO CAP THE ATMOSPHERE OUTSIDE THE MTNS.
WITH EVEN WEAKER SHEAR THAN ON WEDNESDAY...THERE SHOULD BE VERY
LITTLE COVERAGE OVER THE FOOTHILLS OR PIEDMONT ONCE AGAIN. THE
COVERAGE OVER THE MOUNTAINS MAY BE A LITTLE LESS AS WELL CONSIDERING
HOW WEAK THE LAPSE-RATES WILL BE...BUT THERE WILL CERTAINLY BE A FEW
STORMS AROUND. MAX TEMPS WILL BE A DEGREE OR TWO WARMER ON THURSDAY
WITH THE VERY LIGHT DOWNSLOPE FLOW...OR AT LEAST A LACK OF ANY
UPSLOPE COOLING. NEITHER DAY LOOKS TO HAVE MUCH SEVERE POTENTIAL...
BUT YOU CAN NEVER RULE OUT AN ISOLATED MICROBURST THIS TIME OF YEAR.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 100 PM MONDAY...THE 18/12 UTC RUN OF THE OP GFS CONTINUES TO
ADVERTISE RESPONSE ASSOCIATED WITH ENCROACHING AND EVENTUALLY
DISSIPATING WEAK COLD FRONT FRIDAY AND SATURDAY. WILL PLAN ON
MAINTAINING LOW/SLIGHT CHANCE DIURNALLY TIMED TSTM PROBABILITIES
EACH DAY AND MAX TEMPS SVRL CATEGORIES ABOVE CLIMO. IT IS
QUESTIONABLE WHETHER THE PATTERN DURING THE LATTER HALF OF THE
PERIOD WILL FEATURE UPPER RIDGING POKING BACK EASTWARD AS PER THE
GFS OR THE PREFERRED FLATTER WNW FLOW AS THE ECMWF IS SHOWING...BUT
AT THIS POINT...THERE IS LITTLE REASON TO DEVIATE FROM ROUGHLY A
PERSISTENCE FCST TO ROUND OUT THE PERIOD...A SHOTGUN 15-20 DAILY POP
AND TEMPERATURES REMAINING QUITE WARM.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AT KCLT...VFR CONDITIONS ANTICIPATED THRU THE TAF PERIOD. ANY
THUNDERSTORM ACTIVITY WILL REMAIN OVER THE NC MOUNTAINS OR WELL TO
THE NORTH OF THE AIRFIELD. SCATTERED CUMULUS WILL DISSIPATE AROUND
SUNSET.
ELSEWHERE...GENERALLY VFR WITH ONLY SCATTERED CUMULUS DURING THE
AFTERNOON. THE EXCEPTION WIL BE KAVL WHERE SCATTERED THUNDERSTORMS
DICTATE A VCTS UNTIL ABOUT 21Z. ALSO...HAVE LOWERED VSBY IN FOG LATE
TONIGHT TO AROUND 3SM PER MOST GUIDANCE.
OUTLOOK...GENERALLY DRY/VFR CONDITIONS ARE EXPECTED E OF MTNS THRU
THU...WITH SCT AFTN TSTMS OVER THE MTNS EACH DAY AND VALLEY FOG
POSSIBLE LATE EACH NIGHT INTO THE MORNING.
AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...
WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...WINESETT
NEAR TERM...LG
SHORT TERM...MCAVOY
LONG TERM...CSH
AVIATION...LG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
123 PM EDT MON JUN 18 2012
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH THE
WEEK.
&&
.NEAR TERM /THROUGH TUESDAY/...
AS OF 1 PM EDT...WIDELY SCATTERED CONVECTION BEGINNING TO FIRE ALONG
THE BLUE RIDGE AS EXPECTED. EXPECT THAT CONVECTIVE ACTIVITY WILL
CONTINUE TO INCREASE IN COVERAGE INTO THE SCATTERED CATEGORY...BUT
REMAIN CONFINED TO THE MOUNTAINS. UPDRAFTS DO NOT LOOK PARTICUALRY
STRONG AND WITH WEAK WIND FIELDS...THE THREAT OF SEVERE IS MINIMAL.
IT WILL TAKE A 55DBZ CORE TO NEAR 24KFT FOR SEVERE HAIL TODAY.
CURRENT REGIONAL RADARS SHOW MORE ORGANIZED CONVECTION WELL TO THE
NE IN VA ASSOCIATED WITH SOME APPARENT WEAK MCV`S. EXPANDING THE
SCATTERED TYPE POPS OUT INTO THE NC FOOTHILLS AND NC NORTHERN
PIEDMONT THIS AFTERNOON STILL APPEARS PRUDENT AS THIS AREA IS
SKIRTED BY SOME WEAK UPPER FORCING. THE 12Z NAM FORECASTS A MORE
SIGNIFICANT MCV TO MOVE FROM VA INTO CENTRAL NC OVERNIGHT. LOOKS
LIKE MOST OF THE CONVECTION SHOULD AGAIN MISS THE CWA...BUT BRINGING
POPS INTO THE ISOLD RANGE IN THE NORTHERN NC PIEDMONT/FOOTHILLS IS
AGAIN PRUDENT IN DEFERENCE TO THE PROXIMITY OF THE MCV.
PREVIOUS DISCUSSIONS:
AS OF 1015 AM...12Z NAM AND 06Z GFS LOOK CONSIDERABLY OVERDONE IN
REGARD TO THE COVERAGE OF CONVECTION TODAY CONSIDERING THAT SYNOPTIC
FORCING LOOKS TO BE QUITE WEAK. 12Z NAM DOES SHOW SOME WEAK VORT
ENERGY MOVING INTO WESTERN NC THIS AFTERNOON AND SETTLING OVER THE
AREA TONIGHT. HOWEVER...BEST UPPER FORCING WILL REMAIN TO THE NORTH.
THE MESOSCALE MODELS LIKE THE HRRR...GSP WRF AND RAP ARE MUCH LESS
BULLISH IN REGARD TO CONVECTIVE COVERAGE AND CONTAIN IT OVER THE NC
MOUNTAINS. I DID MAKE SOME MINOR ADJUSTMENTS TO THE POP FIELD TO
ALLOW FOR ISOLATED/WIDELY SCATTERED CONVECTION IN THE SC/GA
MOUNTAINS. OTHERWISE...WIND/MOISTURE/THERMAL FIELDS LOOK GOOD.
THE UPPER RIDGE BEGINS REBUILDING IN THE WAKE OF THE OHIO VALLEY
SHORT WAVE....BUT ANOTHER WEAKER WAVE MOVES OVER THE AREA IN THE
WAKE OF THE FIRST WAVE. THIS SHOULD HELP ERODE THE MID LEVEL
SUBSIDENCE INVERSION THAT HAS BEEN CAPPING THE ATMOSPHERE OUTSIDE OF
THE MTNS. AT THE SFC...THE CENTER OF THE HIGH MOVES FARTHER OFF
SHORE BRINGING SLY TO SWLY LOW LVL FLOW BACK OVER THE CWFA. THIS
WILL BRING GREATER AMOUNTS OF LOW TO MID LEVEL MOISTURE IN FROM THE
SOUTH WHICH SHOULD GENERATE AT LEAST WEAK INSTABILITY CWFA WIDE.
EXPECT SCT CONVECTION TO DEVELOP OVER THE MTS AND POSSIBLY THE
ESCARPMENT WITH ISOLATED TO THE SOUTH. RISING THICKNESSES WILL BRING
HIGHER MAX TEMPS...WITH VALUES TOPPING OUT IN THE MID 80S OVER THE
LOWER ELEVATIONS AND UPPER 70S TO LOW 80S FOR THE MTS.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
AS OF 115 PM SUNDAY...A DEEP LAYER RIDGE OF HIGH PRESSURE WILL DRIFT
NORTHWARD...ACROSS THE MID-ATLANTIC STATES DURING THE DAY ON
THURSDAY. THIS WILL PUT THE FA UNDER A LIGHT E TO SE FLOW. MODEL
SOUNDINGS SHOW A MODEST AMOUNT OF CONVECTIVE INHIBITION OVER THE
FOOTHILLS AND PIEDMONT. THE MOUNTAINS LOOK A LITTLE MORE UNSTABLE
THOUGH LAPSE RATES WILL NOT BE STEEP. ANY SHOWERS AND STORMS THAT
DEVELOP SHOULD DRIFT TO THE NORTHWEST...TOWARD ERN TN.
THEREFORE...I/M KEEPING POPS QUITE LOW IN THE FOOTHILLS AND
PIEDMONT...WITH SLIGHT CHANCE TO LOW END CHANCE POPS OVER THE HIGH
TERRAIN. TEMPS WILL BE A FEW DEGREES ABOVE NORMAL...THOUGH WITH THE
ESE FLOW I DON/T SEE FOOTHILL AND PIEDMONT LOCATIONS GETTING MUCH
HOTTER THAN 90 OR 91 DEGREES.
THE RIDGE WILL WEAKEN AND DROP TO THE SOUTH OF THURSDAY...TURNING
THE FLOW FROM LIGHT EASTERLY TO VERY LIGHT WESTERLY ACROSS THE FA.
THE GFS HAS A LITTLE HIGHER DEWPOINT POOLING ALONG THE LEE...BUT
WARM MID LEVELS STILL WORK TO CAP THE ATMOSPHERE OUTSIDE THE MTNS.
WITH EVEN WEAKER SHEAR THAN ON WEDNESDAY...THERE SHOULD BE VERY
LITTLE COVERAGE OVER THE FOOTHILLS OR PIEDMONT ONCE AGAIN. THE
COVERAGE OVER THE MOUNTAINS MAY BE A LITTLE LESS AS WELL CONSIDERING
HOW WEAK THE LAPSE-RATES WILL BE...BUT THERE WILL CERTAINLY BE A FEW
STORMS AROUND. MAX TEMPS WILL BE A DEGREE OR TWO WARMER ON THURSDAY
WITH THE VERY LIGHT DOWNSLOPE FLOW...OR AT LEAST A LACK OF ANY
UPSLOPE COOLING. NEITHER DAY LOOKS TO HAVE MUCH SEVERE POTENTIAL...
BUT YOU CAN NEVER RULE OUT AN ISOLATED MICROBURST THIS TIME OF YEAR.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
AS OF 100 PM MONDAY...THE 18/12 UTC RUN OF THE OP GFS CONTINUES TO
ADVERTISE RESPONSE ASSOCIATED WITH ENCROACHING AND EVENTUALLY
DISSIPATING WEAK COLD FRONT FRIDAY AND SATURDAY. WILL PLAN ON
MAINTAINING LOW/SLIGHT CHANCE DIURNALLY TIMED TSTM PROBABILITIES
EACH DAY AND MAX TEMPS SVRL CATEGORIES ABOVE CLIMO. IT IS
QUESTIONABLE WHETHER THE PATTERN DURING THE LATTER HALF OF THE
PERIOD WILL FEATURE UPPER RIDGING POKING BACK EASTWARD AS PER THE
GFS OR THE PREFERRED FLATTER WNW FLOW AS THE ECMWF IS SHOWING...BUT
AT THIS POINT...THERE IS LITTLE REASON TO DEVIATE FROM ROUGHLY A
PERSISTENCE FCST TO ROUND OUT THE PERIOD...A SHOTGUN 15-20 DAILY POP
AND TEMPERATURES REMAINING QUITE WARM.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AT KCLT...VFR CONDITIONS ANTICIPATED THRU THE TAF PERIOD. ANY
THUNDERSTORM ACTIVITY WILL REMAIN OVER THE NC MOUNTAINS OR WELL TO
THE NORTH OF THE AIRFIELD. SCATTERED CUMULUS WILL DISSIPATE AROUND
SUNSET.
ELSEWHERE...GENERALLY VFR WITH ONLY SCATTERED CUMULUS DURING THE
AFTERNOON. THE EXCEPTION WIL BE KAVL WHERE SCATTERED THUNDERSTORMS
DICTATE A VCTS UNTIL ABOUT 21Z. ALSO...HAVE LOWERED VSBY IN FOG LATE
TONIGHT TO AROUND 3SM PER MOST GUIDANCE.
OUTLOOK...GENERALLY DRY/VFR CONDITIONS ARE EXPECTED E OF MTNS THRU
THU...WITH SCT AFTN TSTMS OVER THE MTNS EACH DAY AND VALLEY FOG
POSSIBLE LATE EACH NIGHT INTO THE MORNING.
AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...
WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...WINESETT
NEAR TERM...LG
SHORT TERM...MCAVOY
LONG TERM...CSH
AVIATION...LG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1026 AM EDT MON JUN 18 2012
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH THE
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1015 AM...12Z NAM AND 06Z GFS LOOK CONSIDERABLY OVERDONE IN
REGARD TO THE COVERAGE OF CONVECTION TODAY CONSIDERING THAT SYNOPTIC
FORCING LOOKS TO BE QUITE WEAK. 12Z NAM DOES SHOW SOME WEAK VORT
ENERGY MOVING INTO WESTERN NC THIS AFTERNOON AND SETTLING OVER THE
AREA TONIGHT. HOWEVER...BEST UPPER FORCING WILL REMAIN TO THE NORTH.
THE MESOSCALE MODELS LIKE THE HRRR...GSP WRF AND RAP ARE MUCH LESS
BULLISH IN REGARD TO CONVECTIVE COVERAGE AND CONTAIN IT OVER THE NC
MOUNTAINS. I DID MAKE SOME MINOR ADJUSTMENTS TO THE POP FIELD TO
ALLOW FOR ISOLATED/WIDELY SCATTERED CONVECTION IN THE SC/GA
MOUNTAINS. OTHERWISE...WIND/MOISTURE/THERMAL FIELDS LOOK GOOD.
PREVIOUS DISCUSSION:
ALL OF THE LINGERING SHOWER ACTIVITY HAS PRETTY MUCH DISSIPATED OVER
THE PAST HOUR OR SO. POCKETS OF CONVECTION CONTINUE TO FIRE WELL TO
OUR NORTH...BUT OTHER THAN THAT EVERY THING IS QUIET. I BUMPED UP
MIN TEMPS A DEGREE OR 2 IN LIGHT OF THE LINGERING STRATOCU AND
WARMER GUIDANCE. HAVE YET TO SEE ANY FOG DEVELOP OVER THE AREA...AND
ITS LOOKING LIKE THE LOCATIONS THAT WILL SEE ANY WILL BE THE FAR
WESTERN NC MT VALLEYS. IF IT DOES DEVELOP...ANY VISBY RESTRICTIONS
SHOULD LIFT BY MID MORNING.
THE UPPER RIDGE BEGINS REBUILDING IN THE WAKE OF THE OHIO VALLEY
SHORT WAVE....BUT ANOTHER WEAKER WAVE MOVES OVER THE AREA IN THE
WAKE OF THE FIRST WAVE. THIS SHOULD HELP ERODE THE MID LEVEL
SUBSIDENCE INVERSION THAT HAS BEEN CAPPING THE ATMOSPHERE OUTSIDE OF
THE MTNS. AT THE SFC...THE CENTER OF THE HIGH MOVES FARTHER OFF
SHORE BRINGING SLY TO SWLY LOW LVL FLOW BACK OVER THE CWFA. THIS
WILL BRING GREATER AMOUNTS OF LOW TO MID LEVEL MOISTURE IN FROM THE
SOUTH WHICH SHOULD GENERATE AT LEAST WEAK INSTABILITY CWFA WIDE.
EXPECT SCT CONVECTION TO DEVELOP OVER THE MTS AND POSSIBLY THE
ESCARPMENT WITH ISOLATED TO THE SOUTH. RISING THICKNESSES WILL BRING
HIGHER MAX TEMPS...WITH VALUES TOPPING OUT IN THE MID 80S OVER THE
LOWER ELEVATIONS AND UPPER 70S TO LOW 80S FOR THE MTS.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 AM SUNDAY...MID AND UPR LVL RIDGE WILL BUILD OVER THE
REGION TUE-WED...WITH A SFC RIDGE BUILDING INTO THE AREA FROM THE E.
THIS WILL PUT THE CWA IN S-SE LOW LVL FLOW WITH ENOUGH MOISTURE FOR
DIURNALLY ENHANCED AFTN-EVE CONVECTION...MAINLY OVER THE MTNS...BOTH
DAYS. TEMPS WILL WARM TO ABOVE AVG WITH TUE HIGHS NEAR 90 ACROSS THE
PIEDMONT...L-M80S MTN VLYS. LOWS WILL RANGE FROM THE M-U60S ACROSS
THE PIEDMONT WITH U50S-L60S MTN VLYS.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 300 AM SUNDAY...UPPER RIDGE OVER THE E US BEGINS TO BREAK DOWN
THU-FRI AS A SERIES OF SHORTWAVES TRACK FROM CENTRL CANADA AND OVER
THE GREAT LAKES. LATEST MODELS CONTINUE TREND OF UPPER TROF DIGGING
OVER THE NE US FRI INTO THE WEEKEND WITH A WEAK COLD FRONT
APPROACHING THE CWA FROM THE NW. IT STILL APPEARS THE FRONT MAY WASH
OUT N OF THE AREA SO TEMPS ARE EXPECTED TO REMAIN ABOVE AVG...WITH
BELOW CLIMO POPS.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
AT KCLT AND ELSEWHERE...VFR CONDITIONS ANTICIPATED THRU TAF PERIOD.
SCATTERED STRATOCU IS STILL STREAMING OVER PORTIONS OF THE NC MTS
AND DOWN INTO THE PIEDMONT AS OF 1030Z. EXPECT ANOTHER ROUND OF CU
TO DEVELOP OVER THE MTS AND ESCARPMENT EARLY IN THE AFTERNOON AND
LINGER WELL INTO THE EVENING. ISOLATED TO SCATTERED SH AND TS ARE
POSSIBLE AGAIN TODAY OVER THE MTS AND ADJACENT FOOTHILLS ONCE SFC
HEATING INCREASES. MOST OF THE ACTIVITY WILL LIKELY OCCUR NORTH OF
THE TAF SITES...HOWEVER KAVL AND TO A LESSER EXTENT KHKY CARRY MORE
THAN A SLIGHT CHANCE POP FOR A FEW HOURS THIS AFTERNOON. WINDS WILL
BE LIGHT AND S TO SWLY THRU THE EVENING WITH MOST AREAS BECOMING
CALM DURING THE OVERNIGHT.
OUTLOOK...GENERALLY DRY CONDITIONS ARE EXPECTED E OF MTNS THRU
THU...WITH SCT AFTN TSTMS OVER THE MTNS EACH DAY AND VALLEY FOG
POSSIBLE EACH NIGHT/MORNING.
AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...
WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...RB
NEAR TERM...LG
SHORT TERM...RB
LONG TERM...RB
AVIATION...JPT
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1229 PM CDT MON JUN 18 2012
.AVIATION...
AN INVERTED UPPER LEVEL TROUGH THAT EXTENDS FROM NEAR HOUSTON
NORTHWARD INTO THE EASTERN PART OF NORTH TEXAS WILL MOVE WEST
NORTHWEST DURING THE NEXT 24 HOURS. ISOLATED TO SCATTERED SHOWERS
AND THUNDERSTORMS WILL OCCUR MAINLY EAST OF I-35/I35E THIS
AFTERNOON AND DISSIPATE AROUND SUNSET. EXPECT VFR CONDITIONS AT
THE AREA AIRPORTS THROUGH THIS EVENING. A 35 KNOT LOW LEVEL JET
IS EXPECTED TO SET UP OVERNIGHT...WHICH MAY ALLOW FOR SOME MVFR
STRATUS TO SPREAD UP ACROSS THE REGION TOWARD DAYBREAK TUESDAY.
HAVE KEPT A MENTION OF BKN018 AT WACO STARTING AT 10Z...AND
BKN020 AT THE METROPLEX TAFS FOR THE 11-16Z PERIOD.
58
&&
.UPDATE...
ANALYSIS THIS MORNING DEPICTS AN UPPER LEVEL INVERTED TROUGH IS
LOCATED NEAR THE SOUTHEAST TEXAS COAST AND WILL CONTINUE TO SLOWLY
CREEP WEST/NORTHWEST TODAY. PER THE RUC ANALYSIS...A WEAK
SHORTWAVE STRETCHED ALONG OUR WESTERN COUNTIES WITH A STRONGER
SHORTWAVE LOCATED OVER THE HILL COUNTRY. THE BEST CHANCE FOR RAIN
TODAY WILL BE OVER OUR SOUTHEASTERN AND EASTERN COUNTIES WHERE AN
EXTENSIVE CUMULUS FIELD IS ALREADY DEVELOPING. EXPECT THE COVERAGE
TO REMAIN ISOLATED TO SCATTERED IN NATURE WITH A FEW STRONG STORMS
POSSIBLE. CAPE VALUES IN THAT AREA WILL INCREASE TO OVER 2000 J/KG
WITH LITTLE TO NO CIN. HOWEVER...SHEAR VALUES WILL AGAIN BE LOW
WITH DEEP LAYER SHEAR VALUES OF 10-20KTS. GUSTY WINDS WILL BE THE
MAIN THREAT WITH ANY STRONGER STORMS.
FOR THE UPDATE...REMOVED THE MENTION OF ISOLATED SHOWERS IN THE
SOUTHWEST THIS MORNING AND INCREASED WIND SPEEDS TO 15 TO 20 MPH
WITH GUSTS UP TO 30 MPH FOR MUCH OF THE WESTERN TWO-THIRDS OF THE
CWA THIS AFTERNOON. WIND SPEEDS ARE ALREADY INCREASING ACROSS THE
REGION IN RESPONSE TO A DEEPENING SURFACE LOW PRESSURE IN THE LEE
OF THE ROCKIES. THE REMAINDER OF THE FORECAST LOOKED ON TRACK.
82/JLD
&&
.PREV DISCUSSION... /ISSUED 409 AM CDT MON JUN 18 2012/
EARLY MORNING WATER VAPOR IMAGERY DEPICTED A SHORTWAVE TROUGH OVER
WEST TX MOVING SOUTHEAST. PRONOUNCED ANTICYCLONIC FLOW WAS NOTED
OVER THE FAR SOUTHWESTERN CONUS AND A WEAKNESS IN THE FLOW ALOFT
WAS IN PLACE OVER THE GULF OF MEXICO FROM THE LA COAST SOUTH TO
THE YUCATAN PENINSULA. EARLY MORNING INFRARED SATELLITE IMAGERY
INDICATED COOLING CLOUD TOPS EXTENDING FROM STEPHENVILLE SOUTHWEST
TOWARDS GOLDTHWAITE AND LAMPASAS. SURFACE OBSERVATIONS HELD ON TO
UPPER 60S DEW POINTS FOR MOST LOCATIONS ACROSS NORTH TX AS OF 08Z
AND DEEP MOISTURE WAS LIKELY STILL IN PLACE OVER MUCH OF THE
FORECAST AREA PER THE 2 INCH PRECIPITABLE WATER (PWAT) VALUE
OBSERVED ON THE 00Z FWD SOUNDING.
THIS MORNING...WENT AHEAD AND MENTIONED ISOLATED RAIN SHOWERS IN
THE FORECAST FOR AREAS WITH COOLING CLOUD TOPS PER EARLY MORNING
INFRARED SATELLITE IMAGERY. THE TWO INCH PWAT OBSERVED ON THE
EVENING SOUNDING COMBINED WITH WEAK LARGE SCALE FORCING FOR ASCENT
ASSOCIATED WITH THE UPSTREAM SHORTWAVE TROUGH IS SUFFICIENT
EVIDENCE TO INCLUDE SOME RAIN SHOWERS IN THE FORECAST AT THIS
TIME. REGIONAL RADARS HAVE NOT YET INDICATED THE PRESENCE OF
PRECIPITATION FROM THESE COOLING CLOUD TOPS...SO KEPT COVERAGE AS
ISOLATED/10 PERCENT FOR THE TIME BEING. WILL UPDATE THE FORECAST
LATER THIS MORNING IF IT LOOKS LIKE COVERAGE WILL BE GREATER THAN
EXPECTED. OTHERWISE...EXPECT RAIN SHOWER ACTIVITY OVER THE
SOUTHWEST CWA TO BE SHORT LIVED THIS MORNING AS THE WEST TX
SHORTWAVE TROUGH MOVES SOUTH OF THE CWA SPREADING LARGE SCALE
FORCING FOR SUBSIDENCE OVER THE WESTERN HALF OF THE FORECAST AREA
BY LATE THIS MORNING.
LARGE SCALE SUBSIDENCE IS EXPECTED TO SCOUR DEEP MOISTURE OFF TO
THE SOUTHEAST THROUGHOUT THE DAY TODAY. THE COMBINATION OF
SUBSIDENCE AND STRONG HEATING THIS AFTERNOON IS EXPECTED TO DRIVE
AFTERNOON DEW POINT VALUES DOWN INTO THE UPPER 50S TO LOWER 60S
FOR MOST LOCATIONS WEST OF THE INTERSTATE 35 CORRIDOR. ASSUMING
THIS OCCURS SURFACE BASED AIR PARCELS ARE EXPECTED TO REMAIN
CAPPED DESPITE THE LACK OF A STRONG ELEVATED MIXED LAYER OVER THE
REGION. THEREFORE AFTERNOON THUNDERSTORMS WEST OF INTERSTATE 35
LOOK UNLIKELY DESPITE A LOSS OF STRONGER SUBSIDENCE BY LATE THIS
AFTERNOON WITH THE SHORTWAVE TROUGH MOVING OVER FAR SOUTH TX.
THIS AFTERNOON THROUGH WEDNESDAY NIGHT...THE SHORTWAVE TROUGH
OVER FAR SOUTH TX IS EXPECTED TO MERGE WITH THE WEAKNESS OVER THE
GULF OF MEXICO AND BECOME A WEAK CUT-OFF LOW OVER THE FAR WESTERN
GULF FOR MUCH OF THIS WEEK. GUIDANCE CONTINUES TO INDICATE AN
UPPER LEVEL INVERTED TROUGH EXTENDING TO THE NORTH OF THIS FEATURE
MOVING PROGRESSIVELY WEST FROM LATE THIS AFTERNOON THROUGH
WEDNESDAY NIGHT. THIS INVERTED TROUGH ESSENTIALLY MARKS A
BOUNDARY BETWEEN A DEEP...MOIST AIRMASS TO THE EAST AND A SOMEWHAT
MODIFIED/DRIER CONTINENTAL AIRMASS TO THE WEST.
THIS MOIST AIRMASS IS EXPECTED TO BE CHARACTERIZED BY MEAGER MID-
LEVEL LAPSE RATES AND PWAT VALUES IN EXCESS OF 1.5 INCHES. DURING
THE AFTERNOON HRS MODELS ARE FAIRLY CONSISTENT IN ADVERTISING
CAPE VALUES OF 1000 TO 1500 J/KG WITH NORMALIZED CAPE VALUES OF
LESS THAN 0.25. ON A FORECAST SOUNDING THIS LOOKS LIKE A TALL BUT
SLENDER CAPE REGION WHICH IS TYPICALLY ASSOCIATED WITH
THUNDERSTORM ACTIVITY WITH EFFICIENT PRECIPITATION PROCESSES.
DEEP LAYER SHEAR IS EXPECTED TO BE VERY WEAK...ESPECIALLY CLOSE TO
THE INVERTED TROUGH. WITH LITTLE CAP IN PLACE EXPECT THAT ISOLATED
TO SCATTERED THUNDERSTORMS WILL DEVELOP WITHIN THIS MOIST AIRMASS
EACH AFTERNOON. THESE STORMS ARE NOT EXPECTED TO BE WELL ORGANIZED
AND ARE THEREFORE UNLIKELY TO PRODUCE SIGNIFICANT SEVERE WEATHER.
IF STORMS MOVE OVER THE SAME LOCATION MULTIPLE TIMES...HEAVY
RAINFALL RATES COULD LEAD TO LOCALIZED FLOODING ISSUES. THIS
INVERTED TROUGH IS EXPECTED TO MOVE OVER THE FAR EASTERN CWA BY
LATE THIS AFTERNOON. IT IS THEN EXPECTED TO MOVE WEST OF THE
INTERSTATE 35 CORRIDOR BY TUESDAY AFTERNOON AND SHOULD BE WEST OF
THE ENTIRE CWA BY WEDNESDAY AFTERNOON. MAINTAINED 20 TO 30 POPS IN
THE FORECAST ALONG AND EAST OF THIS TROUGH AXIS THROUGHOUT THE
PERIOD.
BY THURSDAY MOST GUIDANCE INDICATES THAT UPPER LEVEL RIDGING WILL
BEGIN BUILDING OVER THE CENTRAL PLAINS. THIS WILL SPREAD STRONG
LARGE SCALE FORCING FOR SUBSIDENCE FROM NORTH TO SOUTH OVER NORTH
TX BEGINNING THURSDAY AFTERNOON. HAVE POPS EXITING THE CWA TO THE
SOUTHWEST THURSDAY MORNING AS A RESULT.
EXTENDED...MOST GUIDANCE IS ON BOARD WITH A STRONG UPPER LEVEL
RIDGE OVER THE CENTRAL PLAINS FROM FRIDAY THROUGH EARLY NEXT WEEK.
STRONG FORCING FOR SUBSIDENCE FROM THIS RIDGE APPEARS TO EXTEND
OVER NORTH TX THROUGH THE PERIOD SO MAINTAINED A DRY FORECAST AT
THIS TIME. ALSO WENT WITH HIGHS IN THE UPPER 90S THROUGH THE END
OF THE FORECAST PERIOD AS UPPER RIDGING WILL ALLOW HEAT TO BEGIN
BUILDING OVER NORTH TX WHICH IS TYPICAL FOR THIS TIME OF YEAR.
ASSUMING THE RIDGE IS AS STRONG AS ADVERTISED...WE COULD SEE 100
DEGREES IN THE METROPLEX BY NEXT WEEKEND...BUT HAVE HIGHS JUST
SHY OF THE CENTURY MARK FOR THE TIME BEING.
CAVANAUGH
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 93 75 92 75 91 / 10 10 20 20 30
WACO, TX 94 75 92 76 92 / 10 10 20 20 40
PARIS, TX 91 72 90 71 90 / 20 20 20 20 20
DENTON, TX 94 74 91 74 91 / 10 10 20 20 30
MCKINNEY, TX 93 74 90 73 91 / 10 10 20 20 30
DALLAS, TX 94 75 91 75 91 / 10 10 20 20 30
TERRELL, TX 92 75 90 74 91 / 20 20 20 20 30
CORSICANA, TX 92 75 90 75 90 / 20 20 40 20 40
TEMPLE, TX 94 73 91 75 91 / 20 20 20 20 40
MINERAL WELLS, TX 94 72 91 72 91 / 10 10 10 10 30
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
58/82
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1126 AM CDT MON JUN 18 2012
.UPDATE...
ANALYSIS THIS MORNING DEPICTS AN UPPER LEVEL INVERTED TROUGH IS
LOCATED NEAR THE SOUTHEAST TEXAS COAST AND WILL CONTINUE TO SLOWLY
CREEP WEST/NORTHWEST TODAY. PER THE RUC ANALYSIS...A WEAK
SHORTWAVE STRETCHED ALONG OUR WESTERN COUNTIES WITH A STRONGER
SHORTWAVE LOCATED OVER THE HILL COUNTRY. THE BEST CHANCE FOR RAIN
TODAY WILL BE OVER OUR SOUTHEASTERN AND EASTERN COUNTIES WHERE AN
EXTENSIVE CUMULUS FIELD IS ALREADY DEVELOPING. EXPECT THE COVERAGE
TO REMAIN ISOLATED TO SCATTERED IN NATURE WITH A FEW STRONG STORMS
POSSIBLE. CAPE VALUES IN THAT AREA WILL INCREASE TO OVER 2000 J/KG
WITH LITTLE TO NO CIN. HOWEVER...SHEAR VALUES WILL AGAIN BE LOW
WITH DEEP LAYER SHEAR VALUES OF 10-20KTS. GUSTY WINDS WILL BE THE
MAIN THREAT WITH ANY STRONGER STORMS.
FOR THE UPDATE...REMOVED THE MENTION OF ISOLATED SHOWERS IN THE
SOUTHWEST THIS MORNING AND INCREASED WIND SPEEDS TO 15 TO 20 MPH
WITH GUSTS UP TO 30 MPH FOR MUCH OF THE WESTERN TWO-THIRDS OF THE
CWA THIS AFTERNOON. WIND SPEEDS ARE ALREADY INCREASING ACROSS THE
REGION IN RESPONSE TO A DEEPENING SURFACE LOW PRESSURE IN THE LEE
OF THE ROCKIES. THE REMAINDER OF THE FORECAST LOOKED ON TRACK.
82/JLD
&&
.AVIATION...
AREA RADAR VAD WINDS INDICATE SOUTHERLY FLOW AROUND 30 KT IN THE
020-040 LAYER...WHICH HAS TRANSLATED TO SURFACE WINDS IN THE 10 TO 15
KT RANGE ACROSS MOST OF NORTH TEXAS SINCE MIDNIGHT. SPEEDS HAVE
SLACKENED IN THE PAST HOUR BUT SHOULD PICK UP AGAIN AROUND MID
MORNING AND BECOME SUSTAINED 15-20 KT BY MIDDAY. LOW CLOUDS HAVE
BEEN ABSENT THIS MORNING BUT SHOULD RETURN BEFORE SUNRISE TOMORROW
AS A 35-40 KT LOW LEVEL JET SETS UP OVERNIGHT. WILL INCLUDE MVFR
STRATUS TOMORROW BEGINNING 10Z AT ACT AND 11Z IN THE METROPLEX.
OTHERWISE VFR CONDITIONS ARE EXPECTED AREA-WIDE WITH MAINLY JUST
SOME MID AND HIGH CLOUDS TO CONTEND WITH. PRECIPITATION CHANCES
WILL REMAIN TOO LOW TO MENTION LOW AT AREA TAF SITES UNTIL
PERHAPS DURING THE AFTERNOON AND EVENING HOURS TUESDAY.
30
&&
.PREV DISCUSSION... /ISSUED 409 AM CDT MON JUN 18 2012/
EARLY MORNING WATER VAPOR IMAGERY DEPICTED A SHORTWAVE TROUGH OVER
WEST TX MOVING SOUTHEAST. PRONOUNCED ANTICYCLONIC FLOW WAS NOTED
OVER THE FAR SOUTHWESTERN CONUS AND A WEAKNESS IN THE FLOW ALOFT
WAS IN PLACE OVER THE GULF OF MEXICO FROM THE LA COAST SOUTH TO
THE YUCATAN PENINSULA. EARLY MORNING INFRARED SATELLITE IMAGERY
INDICATED COOLING CLOUD TOPS EXTENDING FROM STEPHENVILLE SOUTHWEST
TOWARDS GOLDTHWAITE AND LAMPASAS. SURFACE OBSERVATIONS HELD ON TO
UPPER 60S DEW POINTS FOR MOST LOCATIONS ACROSS NORTH TX AS OF 08Z
AND DEEP MOISTURE WAS LIKELY STILL IN PLACE OVER MUCH OF THE
FORECAST AREA PER THE 2 INCH PRECIPITABLE WATER (PWAT) VALUE
OBSERVED ON THE 00Z FWD SOUNDING.
THIS MORNING...WENT AHEAD AND MENTIONED ISOLATED RAIN SHOWERS IN
THE FORECAST FOR AREAS WITH COOLING CLOUD TOPS PER EARLY MORNING
INFRARED SATELLITE IMAGERY. THE TWO INCH PWAT OBSERVED ON THE
EVENING SOUNDING COMBINED WITH WEAK LARGE SCALE FORCING FOR ASCENT
ASSOCIATED WITH THE UPSTREAM SHORTWAVE TROUGH IS SUFFICIENT
EVIDENCE TO INCLUDE SOME RAIN SHOWERS IN THE FORECAST AT THIS
TIME. REGIONAL RADARS HAVE NOT YET INDICATED THE PRESENCE OF
PRECIPITATION FROM THESE COOLING CLOUD TOPS...SO KEPT COVERAGE AS
ISOLATED/10 PERCENT FOR THE TIME BEING. WILL UPDATE THE FORECAST
LATER THIS MORNING IF IT LOOKS LIKE COVERAGE WILL BE GREATER THAN
EXPECTED. OTHERWISE...EXPECT RAIN SHOWER ACTIVITY OVER THE
SOUTHWEST CWA TO BE SHORT LIVED THIS MORNING AS THE WEST TX
SHORTWAVE TROUGH MOVES SOUTH OF THE CWA SPREADING LARGE SCALE
FORCING FOR SUBSIDENCE OVER THE WESTERN HALF OF THE FORECAST AREA
BY LATE THIS MORNING.
LARGE SCALE SUBSIDENCE IS EXPECTED TO SCOUR DEEP MOISTURE OFF TO
THE SOUTHEAST THROUGHOUT THE DAY TODAY. THE COMBINATION OF
SUBSIDENCE AND STRONG HEATING THIS AFTERNOON IS EXPECTED TO DRIVE
AFTERNOON DEW POINT VALUES DOWN INTO THE UPPER 50S TO LOWER 60S
FOR MOST LOCATIONS WEST OF THE INTERSTATE 35 CORRIDOR. ASSUMING
THIS OCCURS SURFACE BASED AIR PARCELS ARE EXPECTED TO REMAIN
CAPPED DESPITE THE LACK OF A STRONG ELEVATED MIXED LAYER OVER THE
REGION. THEREFORE AFTERNOON THUNDERSTORMS WEST OF INTERSTATE 35
LOOK UNLIKELY DESPITE A LOSS OF STRONGER SUBSIDENCE BY LATE THIS
AFTERNOON WITH THE SHORTWAVE TROUGH MOVING OVER FAR SOUTH TX.
THIS AFTERNOON THROUGH WEDNESDAY NIGHT...THE SHORTWAVE TROUGH
OVER FAR SOUTH TX IS EXPECTED TO MERGE WITH THE WEAKNESS OVER THE
GULF OF MEXICO AND BECOME A WEAK CUT-OFF LOW OVER THE FAR WESTERN
GULF FOR MUCH OF THIS WEEK. GUIDANCE CONTINUES TO INDICATE AN
UPPER LEVEL INVERTED TROUGH EXTENDING TO THE NORTH OF THIS FEATURE
MOVING PROGRESSIVELY WEST FROM LATE THIS AFTERNOON THROUGH
WEDNESDAY NIGHT. THIS INVERTED TROUGH ESSENTIALLY MARKS A
BOUNDARY BETWEEN A DEEP...MOIST AIRMASS TO THE EAST AND A SOMEWHAT
MODIFIED/DRIER CONTINENTAL AIRMASS TO THE WEST.
THIS MOIST AIRMASS IS EXPECTED TO BE CHARACTERIZED BY MEAGER MID-
LEVEL LAPSE RATES AND PWAT VALUES IN EXCESS OF 1.5 INCHES. DURING
THE AFTERNOON HRS MODELS ARE FAIRLY CONSISTENT IN ADVERTISING
CAPE VALUES OF 1000 TO 1500 J/KG WITH NORMALIZED CAPE VALUES OF
LESS THAN 0.25. ON A FORECAST SOUNDING THIS LOOKS LIKE A TALL BUT
SLENDER CAPE REGION WHICH IS TYPICALLY ASSOCIATED WITH
THUNDERSTORM ACTIVITY WITH EFFICIENT PRECIPITATION PROCESSES.
DEEP LAYER SHEAR IS EXPECTED TO BE VERY WEAK...ESPECIALLY CLOSE TO
THE INVERTED TROUGH. WITH LITTLE CAP IN PLACE EXPECT THAT ISOLATED
TO SCATTERED THUNDERSTORMS WILL DEVELOP WITHIN THIS MOIST AIRMASS
EACH AFTERNOON. THESE STORMS ARE NOT EXPECTED TO BE WELL ORGANIZED
AND ARE THEREFORE UNLIKELY TO PRODUCE SIGNIFICANT SEVERE WEATHER.
IF STORMS MOVE OVER THE SAME LOCATION MULTIPLE TIMES...HEAVY
RAINFALL RATES COULD LEAD TO LOCALIZED FLOODING ISSUES. THIS
INVERTED TROUGH IS EXPECTED TO MOVE OVER THE FAR EASTERN CWA BY
LATE THIS AFTERNOON. IT IS THEN EXPECTED TO MOVE WEST OF THE
INTERSTATE 35 CORRIDOR BY TUESDAY AFTERNOON AND SHOULD BE WEST OF
THE ENTIRE CWA BY WEDNESDAY AFTERNOON. MAINTAINED 20 TO 30 POPS IN
THE FORECAST ALONG AND EAST OF THIS TROUGH AXIS THROUGHOUT THE
PERIOD.
BY THURSDAY MOST GUIDANCE INDICATES THAT UPPER LEVEL RIDGING WILL
BEGIN BUILDING OVER THE CENTRAL PLAINS. THIS WILL SPREAD STRONG
LARGE SCALE FORCING FOR SUBSIDENCE FROM NORTH TO SOUTH OVER NORTH
TX BEGINNING THURSDAY AFTERNOON. HAVE POPS EXITING THE CWA TO THE
SOUTHWEST THURSDAY MORNING AS A RESULT.
EXTENDED...MOST GUIDANCE IS ON BOARD WITH A STRONG UPPER LEVEL
RIDGE OVER THE CENTRAL PLAINS FROM FRIDAY THROUGH EARLY NEXT WEEK.
STRONG FORCING FOR SUBSIDENCE FROM THIS RIDGE APPEARS TO EXTEND
OVER NORTH TX THROUGH THE PERIOD SO MAINTAINED A DRY FORECAST AT
THIS TIME. ALSO WENT WITH HIGHS IN THE UPPER 90S THROUGH THE END
OF THE FORECAST PERIOD AS UPPER RIDGING WILL ALLOW HEAT TO BEGIN
BUILDING OVER NORTH TX WHICH IS TYPICAL FOR THIS TIME OF YEAR.
ASSUMING THE RIDGE IS AS STRONG AS ADVERTISED...WE COULD SEE 100
DEGREES IN THE METROPLEX BY NEXT WEEKEND...BUT HAVE HIGHS JUST
SHY OF THE CENTURY MARK FOR THE TIME BEING.
CAVANAUGH
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 93 75 92 75 91 / 10 10 20 20 30
WACO, TX 94 75 92 76 92 / 10 10 20 20 40
PARIS, TX 91 72 90 71 90 / 20 20 20 20 20
DENTON, TX 94 74 91 74 91 / 10 10 20 20 30
MCKINNEY, TX 93 74 90 73 91 / 10 10 20 20 30
DALLAS, TX 94 75 91 75 91 / 10 10 20 20 30
TERRELL, TX 92 75 90 74 91 / 20 20 20 20 30
CORSICANA, TX 92 75 90 75 90 / 20 20 40 20 40
TEMPLE, TX 94 73 91 75 91 / 20 20 20 20 40
MINERAL WELLS, TX 94 72 91 72 91 / 10 10 10 10 30
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
58/82
AREA FORECAST DISCUSSION
NWS SPOKANE WA
846 AM PDT Mon Jun 18 2012
.SYNOPSIS...
A strong disturbance will bring a good chance of rain to the
region Monday along with gusty winds. Scattered showers Tuesday
will give way to drier and much warmer weather Wednesday and
Thursday. Unsettled weather will return by the end of the week.
&&
.DISCUSSION...
Morning Update: We have went ahead and increased PoPs for a
majority of E WA and N ID through the remainder of the afternoon.
Radar continues to quickly fill in between Omak and Pullman as
large scale ascent along and ahead of a potent shortwave trough
currently in the vicinity of Yakima, WA. There are a few
mesoscale bands of showers pivoting around the main shortwave and
oriented like spokes on a bicycle wheel. Each band appears to
be enhanced by micro-scale circulations best viewed on the radar
loop. One near Chewelah and a second southeast of Omak. Rainfall
rates under these bands will approach 0.20/hr. Otherwise, most
locations will receive around a tenth or less through early
afternoon.
The shortwave is expected to reach the ID/MT border around 00z and
we should see some breaks in the clouds from W and N toward the
SE. Convective temperatures per 12z KOTX sounding were only 64F
and with many locations like already in the mid 50`s, it will
not take much to get showers and isolated thunderstorms firing
this afternoon once the large scale lift passes through. Still a
low confidence forecast on the amount of clearing across the
eastern third of the CWA and exactly the degree of surface based
cape we are able to generate. HRRR would support the idea of
thunder across the north early this afternoon...tracking south
early this evening where the best chance for sun-breaks and deeper
moisture exist. Consequently, we have maintained the threat for
small hail and heavy rain with the strongest cells.
&&
.AVIATION...
12Z TAFS: A cold upper low will drop southeast into Eastern
Washington and North Idaho today. Increased instability will lead
to increased shower activity over the area. Isolated tsra is also
expected between 18z Monday - 03z Tuesday mainly along and east of a
line from Colville to Spokane to Pullman. Small hail is expected
with thunderstorms that develop. The chance of a storm impacting a
TAF site is very low so only a CB cloud group was mentioned in the
TAF forecasts. The low will pull away from the area tonight with
showers decreasing in the evening. Winds will remain gusty at the
TAF sites today but speeds will be a little lower compared to
yesterday. JW
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 59 45 64 47 72 49 / 90 30 10 10 0 0
Coeur d`Alene 56 46 61 46 70 46 / 90 50 40 20 0 0
Pullman 56 42 62 41 73 44 / 100 30 10 10 0 0
Lewiston 64 48 69 50 79 53 / 100 20 10 10 0 0
Colville 62 48 67 48 76 49 / 90 30 40 30 10 10
Sandpoint 55 46 60 44 71 44 / 100 70 60 30 10 10
Kellogg 50 43 55 43 72 47 / 100 80 60 20 10 0
Moses Lake 72 49 73 50 79 52 / 30 10 0 0 0 0
Wenatchee 68 51 70 52 78 55 / 20 0 10 0 0 0
Omak 69 46 72 48 77 50 / 80 10 20 10 0 0
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
332 PM CDT MON JUN 18 2012
.SHORT TERM...
.TONIGHT...FORECAST CONFIDENCE IS MEDIUM.
MESOSCALE MODELS AND MOST OF THE OPERATIONAL MODELS SEEM TO HAVE A
DECENT HANDLE ON THE CONVECTION IN NORTH CENTRAL WI EARLY THIS
AFTERNOON ALONG A PRE-FRONTAL CONVERGENCE ZONE. MODELS DEVELOP A
THUNDERSTORM COMPLEX AND MOVE THE OUTFLOW-TRIGGERED THUNDERSTORMS
SOUTHWARD INTO OUR FORECAST AREA LATE THIS AFTERNOON. IT LOOKS LIKE
AT LEAST THE NORTHERN TIER OF COUNTIES COULD SEE THUNDERSTORMS
BETWEEN 4 PM AND 7 PM THIS AFTERNOON...AND IT COULD REACH MADISON
AND MILWAUKEE AREAS FROM 7 TO 10 PM. MUCH LOWER PROBABILITY ON
ANYTHING REACHING RACINE OR KENOSHA BEFORE THE OUTFLOW BOUNDARY
HANGS UP.
WITH NEARLY 2000 J/KG OF CAPE AND 40 KNOTS OF 6KM BULK SHEAR...LARGE
HAIL AND DAMAGING WINDS WILL BE THE MAIN THREAT. A SEVERE
THUNDERSTORM WATCH IS IN EFFECT FOR THE NORTHERN TIER OF COUNTIES
UNTIL 8 PM. IF THE BOUNDARY REALLY GETS MOVING AND CAN MAINTAIN
STRENGTH AND FIGHT AGAINST THE WARM CAP ACROSS SOUTHERN WI...THEN
THE WATCH COULD BE EXPANDED SOUTHWARD THIS EVENING.
THESE THUNDERSTORMS WILL BE SLOW MOVING AND PRECIPITABLE WATER
VALUES ARE HIGH. MOISTURE TRANSPORT POINTS INTO OUR NORTHEAST
FORECAST AREA AND THIS IS ALSO WHERE THE RIDGE OF THE CORFIDI
VECTORS LINES UP. A CONCERN IS FLASH FLOODING IN NORTHEAST FORECAST
AREA...ESPECIALLY IN THE URBAN AREAS OF FOND DU LAC AND
SHEBOYGAN...POSSIBLY DOWN INTO NORTHERN MILWAUKEE METRO IF HRRR PANS
OUT. THE 17Z HRRR SLOWLY MOVES THE BOUNDARY ACROSS SOUTHEAST WI THIS
EVENING.
WIND ADVISORY WILL REMAIN IN EFFECT THROUGH 8 PM. IT HAS TAKEN A
WHILE TO TAP INTO THE STRONG WINDS ALOFT...BUT SITES ARE JUST
MEETING CRITERIA WITHIN THE LAST HOUR.
.TUESDAY...FORECAST CONFIDENCE IS MEDIUM.
THE FRONTAL BOUNDARY WILL SHIFT BACK UP INTO NORTHERN WISCONSIN
TUESDAY MORNING AND SOUTHERN WI WILL BE BACK IN THE HOT...HUMID AND
BREEZY CONDITIONS THROUGH THE DAY.
.TUESDAY NIGHT AND WEDNESDAY...FORECAST CONFIDENCE MEDIUM.
THE MODELS ARE NOW A LITTLE STRONGER WITH THE NORTH DAKOTA
SHORTWAVE TUESDAY NIGHT...THAT LIFTS NORTHEAST INTO
MANITOBA/WESTERN ONTARIO ON WEDNESDAY.
AS A RESULT SOUTHERN WISCONSIN STAYS IN THE DRY WARM SECTOR
TUESDAY NIGHT BEFORE THE TRAILING COLD FRONT APPROACHES AND MOVES
INTO SOUTH CENTRAL WISCONSIN WEDNESDAY AFTERNOON.
THE 850 MB JET IS AT 50 KNOTS ACROSS THE FORECAST AREA...BUT THE
CONVERGENCE HAS LIFTED WELL TO THE NORTHEAST. ON WEDNESDAY AS THE
FRONT APPROACHES...THE 850 MB WINDS WEAKEN TO 25 KNOTS WITH THE
FORECAST AREA IN THE ENTRANCE REGION BY EVENING...WITH WEAK
MOISTURE CONVERGENCE.
THE 12Z NAM FORECAST SOUNDINGS ARE FAIRLY DRY ABOVE THE LOW LEVEL
CAP. THE NAM WEAKENS THE RATHER STRONG CAP BETWEEN 7 TO 10 THSD
FT DURING THE AFTERNOON. THE ZERO TO 1 KM CAPE INCREASES TO AROUND
1500 J/KG. THIS AND THE APPROACHING FRONT WILL INCREASE THE
CHANCES OF THUNDERSTORMS...DESPITE THE WEAK LOW LEVEL CONVERGENCE
AND WEAK UPPER DIVERGENCE. PRECIPITABLE WATER VALUES ARE 1.75 TO
1.90 INCHES...SO SOME STORMS COULD PRODUCE HEAVY RAINS.
.WEDNESDAY NIGHT AND THURSDAY...FORECAST CONFIDENCE MEDIUM.
THE MAIN NORTHERN STREAM SHORTWAVE REACHES THE JAMES BAY CANADA
REGION THURSDAY WITH THE JET MAX LIFTING NORTHEAST WEDNESDAY NIGHT
BEFORE A WEST/NORTHWEST JET ACROSS THE U.S. CANADIAN BORDER DIPS
ACROSS NORTHERN WISCONSIN.
THE COLD FRONT SHOULD EXIT THE FAR SOUTHEAST WEDNESDAY NIGHT REACHING
THE CENTRAL ILLINOIS AND UPPER OHIO VALLEY REGION ON THURSDAY.
THEREFORE EXPECT SHOWERS AND THUNDERSTORMS TO END WEDNESDAY
NIGHT...WEAKENING AS THE CAPE DIMINISHES WITH LOSS OF HEATING.
ON THURSDAY COOLER AND DRIER AIR WILL ENTER SOUTHERN WISCONSIN AS
HIGH PRESSURE MOVES ACROSS THE MIDWEST.
.LONG TERM...
.FRIDAY AND SATURDAY...FORECAST CONFIDENCE MEDIUM.
ON FRIDAY AND SATURDAY THE 12Z GFS AND 00Z ECMWF ARE IN CLOSE AGREEMENT
IN BRINGING A WEAK SHORTWAVE INTO THE UPPER MISSISSIPPI VALLEY
FRIDAY NIGHT AND INTO THE WESTERN GREAT LAKES REGION SATURDAY.
WITH THE BAROCLINIC ZONE ACROSS WISCONSIN A SURFACE TROUGH MOVES
ACROSS THE AREA SATURDAY...WITH HE MAIN LOW MOVING ACROSS IOWA
AND INTO ILLINOIS. BOTH THE 12Z GFS AND 00Z ECMWF BRING A MODERATE
TO HEAVY RAIN EVENT MAINLY LATE FRIDAY NIGHT AND SATURDAY.
.SUNDAY AND MONDAY...FORECAST CONFIDENCE MEDIUM.
A RATHER STRONG MID/UPPER LEVEL RIDGE BUILDS NORTH INTO THE
NORTHERN PLAINS WITH A NORTHWEST MID/UPPER FLOW ACROSS THE
WESTERN GREAT LAKES.
BOTH THE 12Z GFS AND 00Z ECMWF BRINGS A SURFACE HIGH INTO THE
UPPER MISSISSIPPI VALLEY SUNDAY AND ACROSS WISCONSIN MONDAY.
ONLY THE 12Z GFS KEEPS SOME LIGHT PRECIPITATION OVER THE SOUTH
SUNDAY MORNING. PREFER THE QUICKER 00Z ECMWF/06Z DGEX FOR NOW.
&&
.AVIATION/00Z TAFS/...
STRONG SOUTHWEST GRADIENT WINDS ARE PEAKING LATE THIS AFTERNOON.
THESE WINDS WILL DIMINISH QUICKLY AFTER 00Z TUESDAY.
THUNDERSTORMS ARE DEVELOPING IN NORTH CENTRAL WISCONSIN EARLY THIS
AFTERNOON.
ADDITIONAL THUNDERSTORMS EXPECTED ALONG THE OUTFLOW BOUNDARY SHOULD
SPREAD SOUTHWARD INTO THE FORECAST AREA LATE THIS AFTERNOON. THESE
SHOULD STAY NORTH OF A MADISON TO A MILWAUKEE LINE...BUT INCREASING
CHANCES AT TAF SITES BETWEEN 7 PM AND MIDNIGHT THIS
EVENING...ESPECIALLY TOWARD UES/MKE. BRIEF MVFR CONDITIONS COULD
OCCUR IN AND AROUND ANY THUNDERSTORM ACTIVITY.
HOT...HUMID AND BREEZY AGAIN ON TUESDAY.
&&
.MARINE...STRONG SOUTHWEST GRADIENT WINDS THROUGH EARLY
EVENING...PEAKING MID TO LATE AFTERNOON. A SMALL CRAFT ADVISORY IS
IN EFFECT THROUGH MID EVENING TONIGHT. A GALE WARNING IS IN EFFECT
ROUGHLY SOUTH OF PORT WASHINGTON THROUGH EARLY EVENING. THE
STRONGEST WINDS WILL BE LOCATED CLOSE TO SHORE...DIMINISHING OFF
SHORE DUE TO THE LAKE STABILIZING INFLUENCE. BUT...WAVES WILL BE
HIGHER TOWARD OPEN WATER. SO EITHER WAY...A ROUGH DAY OUT ON THE
WATER TODAY.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR WIZ058>060-062>072.
LM...GALE WARNING UNTIL 7 PM CDT THIS EVENING FOR LMZ644>646.
SMALL CRAFT ADVISORY UNTIL 10 PM CDT THIS EVENING FOR LMZ643.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...MRC
TUESDAY THROUGH SUNDAY...HENTZ
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1245 AM CDT MON JUN 18 2012
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.SYNOPSIS...POTENTIALLY VERY ACTIVE WEATHER THE NEXT FEW DAYS.
VERY BROAD/FLAT UPR TROF CURRENTLY EXTENDING FM THE ERN PAC TO
THE WRN GREAT LAKES RGN WL UNDERGO AMPLIFICATION EARLY IN THE FCST
PERIOD AS THE TROF AXIS CONSOLIDATES OVER THE NRN ROCKIES. THEN
PATTERN WL UNDERGO READJUSTMENT DURING THE WEEK...SO THAT BY NEXT
WEEKEND THERE SHOULD BE A SPRAWLING UPR HIGH OVER THE CENTRAL
PLAINS WITH RIDGING EXTENDING NWD ACRS THE NRN PLAINS/PRAIRIE
PROVINCES OF CANADA...AND WITH UPR TROFS ALONG BOTH COASTS.
WANT TO BE CAREFUL ABOUT FCSTG TOO MUCH PCPN GIVEN THE RECENT DRY
WX...BUT PROGGED PATTEN CERTAINLY SEEMS FAVORABLE FOR ABV NORMAL
PCPN AMNTS. TEMPS WL START OUT WELL ABV NORMAL...THEN TREND BACK
CLOSER TO...BUT STILL SOMEWHAT ABV...SEASONAL NORMALS.
&&
.SHORT TERM...TONIGHT AND MONDAY.
LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LAST NIGHTS
COLD FRONT STRETCHING FROM LAKE HURON TO NORTHERN MISSOURI EARLY
THIS AFTERNOON WHILE BROAD LOW PRESSURE EXISTS OVER THE DAKOTAS.
ELEVATED SHOWERS AND THUNDERSTORMS ARE MOVING OVER SOUTHEAST
MINNESOTA ALONG THE 850MB THETA-E GRADIENT. ADDED SMALL POPS OVER
THE WESTERN CWA AFTER 21Z IN CASE THEY MAKE IT. OTHERWISE...AN
ENERGETIC JET STREAK IS PUSHING A SHORTWAVE INTO NORTH DAKOTA.
CONVECTION IS EXPECTED TO DEVELOP OVER THE ND/SD BORDER AHEAD OF
THIS SHORTWAVE AND THE BROAD SURFACE LOW LATER THIS AFTERNOON. THE
MAIN FORECAST CONCERN IS SEVERE WEATHER CHANCES AS THIS CONVECTION
ORGANIZES LATER TODAY AND MOVES EAST INTO THE REGION.
TONIGHT...THE CHALLENGING FORECAST STARTS OUT RIGHT OFF THE BAT
THIS EVENING AND ONLY BECOMES MORE COMPLEX THROUGH MONDAY. SHOWERS
AND THUNDERSTORMS OVER SOUTHEAST MINNESOTA WILL CONTINUE TO TRACK
EAST THIS AFTERNOON ALONG THE 850MB THETAE GRADIENT/MID-LEVEL
RETURN FLOW. THIS RETURN FLOW IS EXPECTED TO BACK TO THE SOUTH
THIS AFTERNOON AHEAD OF SHORTWAVE ENERGY MOVING INTO NORTH DAKOTA.
AS A RESULT...AM EXPECTING THIS AREA OF SHOWERS AND STORMS TO
WEAKEN BEFORE THEY MOVE INTO CENTRAL WISCONSIN. HOWEVER...THAT
850MB THETA-E GRADIENT DOES PUSH INTO CENTRAL WISCONSIN THIS
EVENING AND DO NOT ENTIRELY TRUST THAT EVERYTHING WILL HAVE
DISSIPATED BY 00Z. ADDED CHANCE POPS OVER THE WESTERN CWA TO
ACCOUNT FOR THIS. OTHERWISE...THINKING AT THIS TIME THAT THE MAIN
SHOW FOR TONIGHT WILL GET GOING LATER THIS AFTERNOON ALONG A WARM
FRONT POSITIONED OVER THE EASTERN ND/SD BORDER INTO CENTRAL
MINNESOTA. THIS CONVECTION SHOULD BECOME INCREASINGLY ELEVATED
THIS EVENING AS SURFACE BASED INSTABILITY IS LOST AND A 40-50KT
LLJ DEVELOPS. TRACKING THIS MCS IS TRICKY DUE TO MASS CONVERGENCE
ALONG THE NOSE OF THE LLJ MOVING NORTHEAST...WHILE INSTABILITY
REMAINS TO THE SOUTH ON THE EDGE OF THE CAP (MID-LEVEL LAPSE RATE
GRADIENT). A ROUGH GUESS WOULD TRACK THE MCS TO THE ENE ON THE
NOSE OF THE LLJ...WHILE THE STRONGEST THUNDERSTORMS MOVE EAST OR
ESE TOWARDS THE INSTABILITY. ELEVATED CAPES OF 1000-1400 J/KG AT
09Z SUGGEST THAT THUNDERSTORMS WILL HAVE POTENTIAL TO SUSTAIN
THEMSELVES AS THEY MOVE INTO N-C AND CENTRAL WISCONSIN AFTER
MIDNIGHT. FREEZING LEVELS ARE HIGH (15KFT)...SO THINK THE MAIN
THREATS WILL BE STRONG GUSTY WINDS DUE TO THE BEEFY LLJ OVERHEAD
AND HEAVY RAINFALL (PWATS 1.7 INCHES AND K-INDEX OF 41). THE MCS
SHOULD GRADUALLY WEAKEN AS IT MOVES INTO NE WISCONSIN LATE
TONIGHT.
MONDAY...THE MCS SHOULD MOVE ACROSS NORTHEAST WISCONSIN BEFORE
EXITING DURING THE MORNING. ANTICIPATE PLENTY OF CLOUD COVER LEFT
OVER FROM THE MCS WHICH SHOULD HOLD BACK TEMPS IN THE MORNING.
VERY WARM TEMPS AT 850MB AND THE HIGH SUN ANGLE SHOULD PARTIALLY
ERODE CLOUD COVER IN THE AFTERNOON. THE AMOUNT OF HEATING WE
RECEIVE WILL LARGELY DETERMINE THUNDERSTORM POTENTIAL DURING THE
PM HOURS. WILL HAVE A COOL FRONT PUSH INTO N-C WISCONSIN LATE IN
THE AFTERNOON...AND POSSIBLE OUTFLOW BOUNDARIES/DIFFERENTIAL
HEATING BOUNDARIES TO SERVE AS A FOCUS FOR CONVECTION. THINK THE
BEST CHANCES OF THUNDERSTORMS WILL BE OVER CENTRAL WISCONSIN AND
THE FOX VALLEY WHERE TEMPS COULD REACH INTO THE UPPER 80S. THE NAM
SUGGESTS THIS POSSIBILITY AS WELL...THOUGH ITS NOT CLEAR IF
CONVECTION CONTINUES ON THE TAIL OF THE MCS...OR REDEVELOPS ON
OTHER BOUNDARIES. 0-6KM BULK SHEAR VALUES OF 40-60KTS AND ML CAPES
OF 1500 J/KG SUGGEST SEVERE WEATHER IS POSSIBLE IF CONVECTION DOES
DEVELOP AND MAIN THREATS SHOULD BE STRONG GUSTY WINDS AND LARGE
HAIL. CONVECTION IS MORE UNCERTAIN ALONG THE COLD FRONT DUE TO
CLOUD COVER CONCERNS. WILL GO WITH HIGHS AROUND 80F NORTH TO UPPER
80S SOUTH.
.LONG TERM...MON NGT THROUGH NEXT SUN. THE FLOW WITHIN THE BASE
OF THE BROAD UPR TROF ACRS THE NWRN PART OF THE CONUS WAS PRETTY
STG FOR JUNE...WITH UPR SPEED MAX OF NEARLY 150 KTS WORKING EWD
ACRS THE PAC NW. THE JET WORKING E COMBINED WITH THE AMPLIFICATION
OF THE LARGE SCALE PATTERN CERTAINLY HAS THE POTENTIAL TO RESULT
IN VERY ACTIVE WX ACRS THE FCST AREA...AS FRONTAL BOUNDARY
OSCILLATES N AND S FOR A COUPLE DAYS. SEVERAL ROUNDS OF SVR
CONVECTION ARE LIKELY IN THE UPPER MIDWEST/GREAT LAKES RGN...WITH
QUESTION BEING WHETHER/WHEN INDIVIDUAL EVENTS AFFECT THE FCST
AREA. TRIED TO ADD A LITTLE RESOLUTION TO POPS...BUT WITH PCPN
CHCS GENERALLY TIED TO POSN OF FRONT AND THAT DEPENDING ON PRIOR
MCS DEVELOPMENT/MVMT...THERE WAS NO WAY TO REALLY GET ARND HAVING
SEVERAL PERIODS WITH HIGHER END CHC POPS AT LEAST SOMEWHERE IN THE
AREA.
ONCE THE MAJOR SHRTWV EJECTING OUT OF THE WRN TROF CROSSES THE RGN
MID-WEEK...A COUPLE DAYS OF QUIETER WEATHER ARE POSSIBLE DURING
THE LATTER PART OF THE WEEK. BUT IT WL BE HARD TO TOTALLY RULE OUT
PCPN AS FCST AREA BECOMES POSITIONED ALONG THE SRN EDGE OF THE
WESTERLIES...AND IN A LCN SUSCEPTIBLE TO CONVECTION FIRING ARND
THE PERIPHERY OF THE DEVELOPING PLAINS UPR HIGH.
&&
.AVIATION...AN AREA OF SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS
THE REGION OVERNIGHT WITH GUSTY WINDS AND MVFR CIGS AND VSBYS.
A STRONG LOW LEVEL JET BY LATE EVENING PRODUCING SOUTH WINDS
AROUND 40 KTS AT 1000 FT AGL. AFTER THE MORNING PCPN...MVFR CIGS
MAY LINGER IN THE MORNING HOURS. SCATTERED CONVECTION WITH MVFR
CIGS AGAIN EXPECTED MONDAY AFTERNOON AND EVENING AS A FRONT DROPS
OVER THE FORECAST AREA.
TDH
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1144 AM MDT MON JUN 18 2012
.AVIATION...18Z TAF ISSUANCE...
VFR CONDITIONS CAN BE EXPECTED AT ALL OF THE AREA AIRPORTS TODAY.
WEST WINDS WILL BE STRONG THIS AFTERNOON WITH GUSTS OF 25 TO 35
KNOTS AT SE WYOMING AIRFIELDS AND 20 TO 25 KNOTS ACROSS THE
WESTERN NEBRASKA PANHANDLE. THESE WINDS WILL SUBSIDE AFTER AROUND
02Z. A FRONT WILL PUSH INTO THE AREA LATE TONIGHT. THIS WILL TURN
THE WINDS NORTHWESTERLY ACROSS THE EASTERN PLAINS THROUGH TUESDAY
MORNING. HAHN
&&
.PREV DISCUSSION... /ISSUED 1011 AM MDT MON JUN 18 2012/
UPDATE...
NW-TO-SE BOUNDARY CURRENTLY RUNS FROM DOUGLAS THROUGH SCOTTSBLUFF
WITH LIGHT SE WINDS AND HIGHER DEWPOINTS TO THE NORTH AND A
WARMER...DRIER...AND ALREADY WELL MIXED BOUNDARY LAYER TO THE
SOUTH. THE MODELS FCST THIS BOUNDARY TO MOVE TO THE NORTHEAST
THROUGH THIS AFTN...WITH THE ENTIRE CWA COMING UNDER THE INFLUENCE
OF THE DRIER SOUTHWESTERLY LLVL FLOW. RFW CONDITIONS CONTINUE TO LOOK
ON TRACK WITH FIRE WEATHER ZONE 311 PROBABLY THE LAST TO REACH
CRITERIA LATE THIS AFTN. LOWERED DEWPOINTS IN THE GRIDS...MORE IN
LINE WITH WHAT THE RUC IS SHOWING.
PREV DISCUSSION... /ISSUED 255 AM MDT MON JUN 18 2012/
SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT.
TODAY...PRIMARY CONCERN TODAY ONCE AGAIN WILL BE FIRE WEATHER
ISSUES. PLEASE SEE FIRE WEATHER SECTION. ANOTHER HOT DAY ON TAP WITH
BRISK WEST SOUTHWEST FLOW ALOFT...700 MB TEMPERATURES 14-18C AND
1000-500 MB THICKNESSES NEAR 5910 METERS. EARLY MORNING TEMPERATURES
RUNNING SOME 5 TO 15 DEGREES WARMER THAN 24 HOURS AGO WITH DEWPOINTS
SOME 5 TO 15 DEGREES LOWER AT MOST LOCATIONS. BASED ON PERSISTENCE...
BELIEVE HIGH TEMPERATURES TODAY WILL BE CLOSE TO THOSE OF YESTERDAY.
TONIGHT...SHORTWAVE TROUGH MOVES EASTWARD ACROSS MONTANA AND
NORTHERN WYOMING SENDING A COLD FRONT ACROSS OUR COUNTIES AFTER
MIDNIGHT. WITH VERY LIMITED LOW AND MID LEVEL MOISTURE...THIS FRONT
WILL BE DRY AS IT PASSES ACROSS OUR COUNTIES WITH A WIND SWITCH TO
WEST AND NORTHWEST.
TUESDAY...QUITE A BIT COOLER IN THE WAKE OF THE PASSING COLD FRONT
WITH HIGH TEMPERATURES IN THE 70S AND 80S AS 700 MB TEMPERATURES
RANGE FROM 4C IN THE NORTH TO 12C IN THE SOUTH. STILL LOOKS LIKE LOW
AND MID LEVEL MOISTURE WILL BE TOO LIMITED FOR SHOWERS AND
THUNDERSTORMS.
TUESDAY NIGHT...MAY HAVE ENOUGH LOW LEVEL CONVERGENCE AND MOISTURE
FOR ISOLATED SHOWERS TO DEVELOP EAST OF INTERSTATE 25 AND WILL
MAINTAIN THESE WHICH BLENDS WELL WITH OUR NEIGHBORS TO THE NORTH AND
EAST.
WEDNESDAY...ONCE AGAIN...LOW AND MID LEVEL MOISTURE LOOKS TOO SCANT
FOR ANY AFTERNOON OR EVENING SHOWERS OR THUNDERSTORMS. CONTINUED
COOLER TEMPERATURES WITH 700 MB TEMPERATURES FROM 6-13C YIELDING
HIGH TEMPERATURES IN THE 70S TO LOWER 80S.
WEDNESDAY NIGHT...ANOTHER RELATIVELY COOL AND CLEAR NIGHT WITH LIGHT
WINDS AS THE AIRMASS BEGINS TO MODERATE.
LONG TERM...THURSDAY THROUGH MONDAY
LOOKING AT THE WARMEST TEMPERATURES OF THE YEAR SO FAR TOWARDS THE
END OF THE WEEK. FORECAST CHALLENGES DEAL WITH THESE TEMPERATURES
AND FIRE WEATHER CONCERNS ASSOCIATED WITH THESE HIGH TEMPERATURES.
DRY FORECAST AT LEAST UNTIL SATURDAY AS HEIGHTS BUILD OVER THE
AREA. BY THURSDAY AFTERNOON...WE ARE LOOKING AT 588DM HEIGHTS OVER
THE CWFA WITH 700MB TEMPERATURES OF +16 TO +18C. BY FRIDAY...GFS
SHOWING WIDESPREAD +18C TEMPERATURES OVER THE CWFA WHILE THE
LATEST ECMWF SHOWING +20C 700MB TEMPERATURES. CONTINUED
FORECASTING SEVERAL DEGREES OVER MAX/MIN TEMPERATURE GUIDANCE.
LOOKS LIKE POSSIBLY A WINDY PERIOD AS WELL FRIDAY AS 700MB WINDS
OFF THE GFS SHOWING 25-30KTS OVER CARBON AND ALBANY COUNTIES. BY
FRIDAY NIGHT...IT LOOKS LIKE THE UPPER RIDGE AXIS FINALLY PUSHES
EAST OF OUR AREA AND TEMPERATURES BEGIN TO COOL A LITTLE. FOR THE
MOST PART A DRY FORECAST THROUGH THE WEEKEND...THOUGH BOTH THE
ECMWF AND GFS START TO PAINT SOME SHOWERS OVER THE MOUNTAINS
SUNDAY. WILL WAIT AND SEE IF THIS HAPPENS AS BOTH MODELS HAVE BEEN
TOO MOIST FOR US ON SEVERAL PAST EVENTS. ODDS ARE...WE STAY DRY.
&&
.FIRE WEATHER...CRITICAL FIRE WEATHER CONDITIONS TODAY WITH NEARLY
ALL LOCATIONS SEEING MINIMUM AFTERNOON RELATIVE HUMIDITIES UNDER 15
PERCENT ALONG WITH WIND GUSTS IN EXCESS OF 25 MPH...ESPECIALLY WEST
OF INTERSTATE 25. EXPECT A DRY COLD FRONTAL PASSAGE AFTER MIDNIGHT
TONIGHT WITH WINDS BECOMING WEST AND NORTHWEST...ALTHOUGH HUMIDITY
RECOVERIES WILL BE MINIMAL ESPECIALLY FROM WHEATLAND TO CHEYENNE.
MORE CRITICAL FIRE WEATHER CONDITIONS LOOK LIKELY FOR TUESDAY
AFTERNOON ACROSS MUCH OF SOUTHEAST WYOMING EVEN WITH COOLER
TEMPERATURES...AS MINIMUM AFTERNOON RELATIVE HUMIDITIES FALL UNDER
15 PERCENT ALONG WITH WIND GUSTS IN EXCESS OF 25 MPH.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...RED FLAG WARNING UNTIL 9 PM MONDAY FOR WYZ101-WYZ102-WYZ103-
WYZ104-WYZ106-WYZ107-WYZ108-WYZ109-WYZ110-WYZ111-WYZ112-
WYZ113-WYZ116-WYZ117-WYZ118-WYZ119.
FIRE WEATHER WATCH FROM 10 AM TUESDAY TO 9 PM TUESDAY FOR WYZ103-
WYZ104-WYZ106-WYZ107-WYZ108-WYZ109-WYZ110-WYZ111-WYZ112-
WYZ113-WYZ116-WYZ117-WYZ118-WYZ119.
NE...RED FLAG WARNING UNTIL 9 PM MONDAY FOR NEZ002-NEZ003-NEZ019-
NEZ020-NEZ021-NEZ054-NEZ055-NEZ095-NEZ096.
&&
$$
SHORT TERM/FIRE WEATHER...RUBIN
LONG TERM...CLAYCOMB
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1011 AM MDT MON JUN 18 2012
.UPDATE...
NW-TO-SE BOUNDARY CURRENTLY RUNS FROM DOUGLAS THROUGH SCOTTSBLUFF
WITH LIGHT SE WINDS AND HIGHER DEWPOINTS TO THE NORTH AND A
WARMER...DRIER...AND ALREADY WELL MIXED BOUNDARY LAYER TO THE
SOUTH. THE MODELS FCST THIS BOUNDARY TO MOVE TO THE NORTHEAST
THROUGH THIS AFTN...WITH THE ENTIRE CWA COMING UNDER THE INFLUENCE
OF THE DRIER SOUTHWESTERLY LLVL FLOW. RFW CONDITIONS CONTINUE TO LOOK
ON TRACK WITH FIRE WEATHER ZONE 311 PROBABLY THE LAST TO REACH
CRITERIA LATE THIS AFTN. LOWERED DEWPOINTS IN THE GRIDS...MORE IN
LINE WITH WHAT THE RUC IS SHOWING.
&&
.PREV DISCUSSION... /ISSUED 533 AM MDT MON JUN 18 2012/
AVIATION...12Z TAFS
VFR CONDITIONS EXPECTED WITH GUSTY WESTERLY WINDS FROM 15Z TIL 02Z
OR SO. BESIDES THE GUSTY WINDS...NO IMPACTS FROM WEATHER IS
EXPECTED FOR FLIGHT OPERATIONS TODAY.
CLAYCOMB
PREV DISCUSSION... /ISSUED 255 AM MDT MON JUN 18 2012/
SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT.
TODAY...PRIMARY CONCERN TODAY ONCE AGAIN WILL BE FIRE WEATHER
ISSUES. PLEASE SEE FIRE WEATHER SECTION. ANOTHER HOT DAY ON TAP WITH
BRISK WEST SOUTHWEST FLOW ALOFT...700 MB TEMPERATURES 14-18C AND
1000-500 MB THICKNESSES NEAR 5910 METERS. EARLY MORNING TEMPERATURES
RUNNING SOME 5 TO 15 DEGREES WARMER THAN 24 HOURS AGO WITH DEWPOINTS
SOME 5 TO 15 DEGREES LOWER AT MOST LOCATIONS. BASED ON PERSISTENCE...
BELIEVE HIGH TEMPERATURES TODAY WILL BE CLOSE TO THOSE OF YESTERDAY.
TONIGHT...SHORTWAVE TROUGH MOVES EASTWARD ACROSS MONTANA AND
NORTHERN WYOMING SENDING A COLD FRONT ACROSS OUR COUNTIES AFTER
MIDNIGHT. WITH VERY LIMITED LOW AND MID LEVEL MOISTURE...THIS FRONT
WILL BE DRY AS IT PASSES ACROSS OUR COUNTIES WITH A WIND SWITCH TO
WEST AND NORTHWEST.
TUESDAY...QUITE A BIT COOLER IN THE WAKE OF THE PASSING COLD FRONT
WITH HIGH TEMPERATURES IN THE 70S AND 80S AS 700 MB TEMPERATURES
RANGE FROM 4C IN THE NORTH TO 12C IN THE SOUTH. STILL LOOKS LIKE LOW
AND MID LEVEL MOISTURE WILL BE TOO LIMITED FOR SHOWERS AND
THUNDERSTORMS.
TUESDAY NIGHT...MAY HAVE ENOUGH LOW LEVEL CONVERGENCE AND MOISTURE
FOR ISOLATED SHOWERS TO DEVELOP EAST OF INTERSTATE 25 AND WILL
MAINTAIN THESE WHICH BLENDS WELL WITH OUR NEIGHBORS TO THE NORTH AND
EAST.
WEDNESDAY...ONCE AGAIN...LOW AND MID LEVEL MOISTURE LOOKS TOO SCANT
FOR ANY AFTERNOON OR EVENING SHOWERS OR THUNDERSTORMS. CONTINUED
COOLER TEMPERATURES WITH 700 MB TEMPERATURES FROM 6-13C YIELDING
HIGH TEMPERATURES IN THE 70S TO LOWER 80S.
WEDNESDAY NIGHT...ANOTHER RELATIVELY COOL AND CLEAR NIGHT WITH LIGHT
WINDS AS THE AIRMASS BEGINS TO MODERATE.
LONG TERM...THURSDAY THROUGH MONDAY
LOOKING AT THE WARMEST TEMPERATURES OF THE YEAR SO FAR TOWARDS THE
END OF THE WEEK. FORECAST CHALLENGES DEAL WITH THESE TEMPERATURES
AND FIRE WEATHER CONCERNS ASSOCIATED WITH THESE HIGH TEMPERATURES.
DRY FORECAST AT LEAST UNTIL SATURDAY AS HEIGHTS BUILD OVER THE
AREA. BY THURSDAY AFTERNOON...WE ARE LOOKING AT 588DM HEIGHTS OVER
THE CWFA WITH 700MB TEMPERATURES OF +16 TO +18C. BY FRIDAY...GFS
SHOWING WIDESPREAD +18C TEMPERATURES OVER THE CWFA WHILE THE
LATEST ECMWF SHOWING +20C 700MB TEMPERATURES. CONTINUED
FORECASTING SEVERAL DEGREES OVER MAX/MIN TEMPERATURE GUIDANCE.
LOOKS LIKE POSSIBLY A WINDY PERIOD AS WELL FRIDAY AS 700MB WINDS
OFF THE GFS SHOWING 25-30KTS OVER CARBON AND ALBANY COUNTIES. BY
FRIDAY NIGHT...IT LOOKS LIKE THE UPPER RIDGE AXIS FINALLY PUSHES
EAST OF OUR AREA AND TEMPERATURES BEGIN TO COOL A LITTLE. FOR THE
MOST PART A DRY FORECAST THROUGH THE WEEKEND...THOUGH BOTH THE
ECMWF AND GFS START TO PAINT SOME SHOWERS OVER THE MOUNTAINS
SUNDAY. WILL WAIT AND SEE IF THIS HAPPENS AS BOTH MODELS HAVE BEEN
TOO MOIST FOR US ON SEVERAL PAST EVENTS. ODDS ARE...WE STAY DRY.
FIRE WEATHER...CRITICAL FIRE WEATHER CONDITIONS TODAY WITH NEARLY
ALL LOCATIONS SEEING MINIMUM AFTERNOON RELATIVE HUMIDITIES UNDER 15
PERCENT ALONG WITH WIND GUSTS IN EXCESS OF 25 MPH...ESPECIALLY WEST
OF INTERSTATE 25. EXPECT A DRY COLD FRONTAL PASSAGE AFTER MIDNIGHT
TONIGHT WITH WINDS BECOMING WEST AND NORTHWEST...ALTHOUGH HUMIDITY
RECOVERIES WILL BE MINIMAL ESPECIALLY FROM WHEATLAND TO CHEYENNE.
MORE CRITICAL FIRE WEATHER CONDITIONS LOOK LIKELY FOR TUESDAY
AFTERNOON ACROSS MUCH OF SOUTHEAST WYOMING EVEN WITH COOLER
TEMPERATURES...AS MINIMUM AFTERNOON RELATIVE HUMIDITIES FALL UNDER
15 PERCENT ALONG WITH WIND GUSTS IN EXCESS OF 25 MPH.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...RED FLAG WARNING UNTIL 9 PM MONDAY FOR WYZ101-WYZ102-WYZ103-
WYZ104-WYZ106-WYZ107-WYZ108-WYZ109-WYZ110-WYZ111-WYZ112-
WYZ113-WYZ116-WYZ117-WYZ118-WYZ119.
FIRE WEATHER WATCH FROM 10 AM TUESDAY TO 9 PM TUESDAY FOR WYZ103-
WYZ104-WYZ106-WYZ107-WYZ108-WYZ109-WYZ110-WYZ111-WYZ112-
WYZ113-WYZ116-WYZ117-WYZ118-WYZ119.
NE...RED FLAG WARNING UNTIL 9 PM MONDAY FOR NEZ002-NEZ003-NEZ019-
NEZ020-NEZ021-NEZ054-NEZ055-NEZ095-NEZ096.
&&
$$
UPDATE...FINCH
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1239 AM EDT WED JUN 20 2012
.SYNOPSIS...
A WEAK COLD FRONT WILL ACROSS THE REGION WEDNESDAY. A WARM FRONT
WILL THEN CROSS THE STATE ON THURSDAY FOLLOWED BY ANOTHER COLD
FRONT ON FRIDAY.
&&
.NEAR TERM /THROUGH TODAY/...
1240 AM UPDATE...THE GOING FORECAST IS PRETTY MUCH ON TRACK.
STRATUS HAS MADE IT AS FAR NORTH AS BANGOR AND SHOULD CONTINUE TO
SLOWLY LIFT NORTH THROUGH DAYBREAK. SEEING SOME SHOWERS RUNNING
JUST TO THE NORTH OF THE ST JOHN VALLEY, SO KEPT A SLIGHT CHANCE
OF A SHOWER OR THUNDERSTORM ACROSS THE NORTH. THE MAIN CHANGE WAS
TO ADD PATCHY FOG EVERYWHERE, AS DEWPOINTS ARE IN THE UPPER 50S
AND WE`RE STARTING TO SEE SOME CLEARING SKIES ACROSS THE NORTH. NO
OTHER CHANGES WERE NEEDED.
PREVIOUS DISCUSSION:
CHALLENGES THIS TERM WILL BE CONVECTION AND STRATUS.
ATTM, NOT OVERLY IMPRESSED W/THE POTENTIAL FOR TSTMS TO FIRE UP
ACROSS THE NORTHERN AND WESTERN CWA.
LATEST RUC SOUNDINGS DO SUPPORT SB CAPES OF 700+ JOULES
W/MOISTURE UP THROUGH 700 MBS ACROSS THE FAR W AND N BUT AS THE
AFTERNOON WEARS ON AND EVENING APCHS, THE MOISTURE IS LIMITED TO
850MBS AND BELOW AND ATMOSPHERE STABILIZES IN THE LLVLS. MID LEVEL
LAPSE RATES ARE CLOSE TO 6.0 C/KM AND HOLD THERE THROUGH THE
NIGHT. THERE IS SOME MID LEVEL FORCING INITIALLY BUT THAT IS GONE
BY 06Z AS THE FRONT APCHS. ATTM, DECIDED ON ISOLD TSTMS AND KEPT
POPS NO MORE THAN 40% ACROSS THE FAR N AND W FOR SHOWERS.
SKY COVER WILL BE A CHALLENGE TONIGHT AS S FLOW INITIALLY WILL
ALLOW FOR STRATUS TO DEVELOP AGAIN LATER THIS EVENING INTO THE
OVERNIGHT PERIOD ESPECIALLY ACROSS THE DOWNEAST INTO THE CENTRAL
HIGHLANDS INTO THE MLT AND HUL REGIONS. FURTHER N AND W, WIND
VEERING MORE SW OVERNIGHT SHOULD LIMIT PROGRESSION OF THE STRATUS.
FOG POTENTIAL IS HIGHEST OVER THE DOWNEAST AND COAST AND DECIDED
TO KEEP THE MENTION OF FOG IN THERE FOR THESE AREAS. FURTHER N AND
W, KEPT FOG OUT DUE TO WIND SPEEDS STAYING UP FOR ONE AND DIRECTION
MORE WSW BY MORNING. THIS WILL ALSO KEEP TEMPERATURES UP WITH
READINGS SOME 5 DEGREES WARMER THAN THEY WERE LAST NIGHT AND EARLY
THIS MORNING.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY/...
A SMALL TROUGH OF LOW PRESSURE SLIDING ACROSS THE NORTH WILL MOVE
EAST OF THE AREA ON WEDNESDAY. THIS WILL LEAVE A WEAK FRONTAL
BOUNDARY DRAPED ACROSS THE CENTRAL PART OF THE STATE DIVIDING WARM
AIR TO THE NORTH FROM HOT AND HUMID AIR TO THE SOUTH AND WEST.
SOME MOISTURE WILL CONCENTRATED ALONG THIS BOUNDARY AND A
THUNDERSTORM MAY AFFECT CENTRAL OR DOWNEAST AREAS JUST ALONG OR
SOUTH OF THE FRONTAL BOUNDARY. THE STRONGEST INSTABILITY SEEMS TO
BE DURING THE MIDDAY ACROSS DOWNEAST AREAS AS THE SURFACE TROUGH
PUSHES THROUGH. THE FRONT WILL REMAIN IN PLACE WEDNESDAY NIGHT. A
SMALL LOW LIFTING NORTH AND WEST OF THE AREA ON THURSDAY WILL PULL
THE FRONTAL BOUNDARY BACK NORTH AS A WARM FRONT. MODEL SOUNDINGS
SHOW INCREASING INSTABILITY ALONG AND JUST SOUTHWEST OF THE WARM
FRONT ACROSS THE WESTERN EDGE OF OUR REGION THURSDAY AFTERNOON.
WARMER AND MORE HUMID AIR WILL BE PULLED INTO THE AREA LATE
THURSDAY INTO THURSDAY NIGHT. SOME THUNDERSTORMS MAY FORM ALONG
THE WARM FRONT THURSDAY AFTERNOON OR EVENING WITH THE BEST CHANCES
FOR STORMS IN THE WEST. THURSDAY NIGHT WILL BE A WARM AND HUMID
NIGHT ACROSS THE REGION BEHIND THE WARM FRONT. A COLD FRONT WILL
THEN APPROACH ON FRIDAY BRINGING A GOOD CHANCE FOR SHOWERS AND
THUNDERSTORMS ACROSS THE STATE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
LOW PRESSURE WILL DRAW A COLD FRONT ACROSS THE REGION FRIDAY NIGHT
WITH A CHANCE OF SHOWERS/THUNDERSTORMS DURING THE EVENING...WITH
DIMINISHING SHOWER CHANCES OVERNIGHT. THE LOW WILL REMAIN IN THE
VICINITY OF THE REGION SATURDAY KEEPING A CHANCE OF
SHOWERS/THUNDERSTORMS MOSTLY DURING THE AFTERNOON. A CHANCE OF
SHOWERS WILL LINGER SATURDAY NIGHT WHILE THE LOW MOVES EAST. A
SHOWER/THUNDERSTORM WILL REMAIN POSSIBLE SUNDAY WITH A LINGERING
TROF IN THE WAKE OF THE LOW. SURFACE LOW PRESSURE WILL THEN
DEVELOP TO THE WEST OF THE REGION SUNDAY NIGHT/MONDAY WHILE AN
UPPER LOW MOVES SOUTH TOWARD THE GREAT LAKES REGION. SHOWER
CHANCES WILL INCREASE ACROSS THE REGION SUNDAY NIGHT THROUGH
MONDAY...WITH A STEADIER RAIN DEVELOPING LATER MONDAY. THE
SURFACE/UPPER LOW WILL THEN REMAIN ACROSS WESTERN NEW ENGLAND
MONDAY NIGHT THROUGH TUESDAY KEEPING A STEADY RAIN ACROSS THE
FORECAST AREA. THE RAIN SHOULD TAPER TO SHOWERS TUESDAY NIGHT.
TEMPERATURES SHOULD BE AT NEAR NORMAL LEVELS SATURDAY/SUNDAY...WITH
BELOW NORMAL LEVEL TEMPERATURES MONDAY/TUESDAY.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
NEAR TERM: VFR ATTM GOING TO MVFR LATER THIS EVENING AND THEN IFR
BY EARLY WEDNESDAY MORNING. BEST CHC FOR IFR WILL BE FROM HUL ON
SOUTH TO BGR AND BHB. CONDITIONS WILL GO VFR AFTER 12Z WEDNESDAY
W/BGR AND BHB TAKING A WHILE LONGER TO IMPROVE.
SHORT TERM: GENERALLY VFR CONDITIONS ARE EXPECTED WEDNESDAY
THROUGH FRIDAY. THE EXCEPTIONS WILL BE IN ANY THUNDERSTORMS
MAINLY LATE THURSDAY INTO FRIDAY AND IN COASTAL FOG LATE
WEDNESDAY NIGHT AND AGAIN LATE THURSDAY NIGHT. FOG MAY LINGER FOR
A WHILE EACH DAY ALONG THE IMMEDIATE COAST. OCCASIONAL MVFR
CONDITIONS ARE POSSIBLE ACROSS THE REGION FRIDAY NIGHT. OCCASIONAL
MVFR CONDITIONS COULD THEN OCCUR WITH ANY SHOWERS OR THUNDERSTORMS
SATURDAY/SUNDAY.
&&
.MARINE...
NEAR TERM: KEPT THE MENTION OF THE SWELL IN THE FCST TONIGHT AS A
8-9 SECOND PERIOD IS OCCURRING ATTM. THE LATEST WAVE GUIDANCE
INCLUDING THE SWAN GUIDANCE IS SHOWING SEAS REACHING 5 FT TONIGHT
W/THE SOUTHERLY SWELL. DECISION WAS TO BRING SEAS UP A FOOT W/A
RANGE OF 3-5 FT TONIGHT. SEAS LOOK LIKE THEY WILL SUBSIDE LATER
WEDNESDAY AS REFERENCED IN THE SHORT TERM AS WINDS GO OFFSHORE.
SHORT TERM: SWELL FROM A SMALL SUBTROPICAL LOW OFF THE COAST OF
NOVA SCOTIA WILL RESULT IN SEAS NEAR 5 FT EARLY WED.
OTHERWISE...WINDS AND SEAS ARE EXPECTED TO BE BELOW SCA THROUGH
THE PERIOD. HUMID AIR MOVING OVER THE WATERS WILL RESULT IN FOG
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HASTINGS/HEWITT
SHORT TERM...BLOOMER
LONG TERM...NORCROSS
AVIATION...HASTINGS/HEWITT
MARINE...HASTINGS/HEWITT/BLOOMER
AREA FORECAST DISCUSSION
NWS BILLINGS MT
341 AM MDT WED JUN 20 2012
.SHORT TERM...VALID FOR TDY AND THU...
AFTER ONE MORE OPPORTUNITY FOR SHOWERS OR PERHAPS A STORM TODAY...
A WARM AND MAINLY DRY PERIOD WILL START THU AS HEIGHTS RISE ALOFT.
MOISTURE CHANNEL IMAGERY AT 09 UTC REVEALS A BIT MORE COMPLEX FLOW
THAN WE EXPECTED AT THIS TIME YESTERDAY...WITH AN ADDITIONAL SHORT
WAVE MOVING INTO WESTERN WY. THAT FEATURE HAS BEEN RESPONSIBLE FOR
SHOWERS OVER SOUTH CENTRAL MT OVERNIGHT...BUT SINCE BOTH THAT WAVE
AND ITS MORE NORTHERN COUNTERPART WILL BE HEADING EAST OF MT TODAY
WE WILL MAINLY DEAL WITH LINGERING CYCLONIC FLOW IN THEIR WAKE.
TODAY...WEAK CONVECTION IS EXPECTED IN CYCLONIC FLOW ALOFT...WHICH
SUPPORTS POPS IN THE 30 PERCENT RANGE FOR MOST AREAS. A BIT BETTER
CONCENTRATION OF CONVECTION COULD OCCUR ON THE LEADING EDGE OF THE
SUBTLE 1.5 PVU LOWERING THAT THE 00 UTC NAM AND GFS TAKE FROM NEAR
GREAT FALLS AT 09 UTC TO MILES CITY BY 18 UTC. SHOWERS AROUND THAT
FEATURE HAVE HELD TOGETHER IN NORTH CENTRAL MT OVERNIGHT DESPITE A
STABLE BOUNDARY LAYER...WHICH ADDS CONFIDENCE TO OUR BELIEF THAT A
SCATTERING OF CONVECTION WILL OCCUR ACROSS OUR AREA TODAY. THAT IS
FURTHER SUPPORTED BY THE LAST FEW HRRR RUNS...AND THE QPF FROM THE
00 UTC GFS AND NAM AS WELL. THE FORECAST DOES CONTAIN A MENTION OF
THUNDERSTORMS TOO...WITH THE CALIBRATED PROBABILITIES OF THAT FROM
THE 21 UTC SREF NEAR 10 PERCENT. HOWEVER...FORECAST SOUNDINGS SHOW
MARGINAL BUOYANCY...AND SOME HINTS OF MID-LEVEL SUBSIDENCE...WHICH
SHOULD KEEP MOST UPDRAFTS FROM GROWING TALL ENOUGH FOR TOO MUCH IN
THE WAY OF LIGHTNING PRODUCTION. IT IS ALSO POSSIBLE THAT DOWNWARD
MOTION WILL RESULT IN LOWER-THAN-EXPECTED CONVECTIVE COVERAGE OVER
PARTS OF THE AREA.
TONIGHT...WE CONTINUED SOME SLIGHT CHANCE POPS FOR SOUTHEASTERN MT
UNTIL 03 UTC IN ORDER TO GIVE ANY RESIDUAL CONVECTION TIME TO END.
THIS IS SUPPORTED BY THE 00 UTC 4 KM WRF-NMM...WHICH DOES NOT TAIL
OFF ALL OF ITS WEAK CONVECTION NEAR MILES CITY AND BAKER UNTIL THE
LATE EVENING HOURS. WEAK SURFACE RIDGING WILL INFLUENCE THE REGION
OVERNIGHT...WHICH SHOULD ALLOW FOR DECENT RADIATIONAL COOLING. OUR
FORECAST LOWS ARE ON THE COLD SIDE OF THE GUIDANCE SPREAD BASED ON
THE DRY BOUNDARY LAYER AIR AND LIGHT WINDS NEAR THE RIDGE. THE AIR
MASS IS NOT VERY COOL THOUGH...SO WE MAY ADMITTEDLY BE TOO COLD IN
SPOTS. NONETHELESS...NAM-BASED GUIDANCE HANDLED A SIMILAR SCENARIO
LAST FRI NIGHT WELL...SO WE LEANED ON IT FOR LOWS TONIGHT AS WELL.
THU...WARM AIR ADVECTION WILL OCCUR AS HEIGHTS ALOFT BEGIN RISING.
THE LOWER AND MIDDLE 80S F WILL BE AN EASY TARGET ON THE PLAINS AS
MIXING TO 700 HPA OCCURS. EVEN THOUGH THERE WILL BE LIGHT EASTERLY
LOW-LEVEL FLOW IN THE AFTERNOON...WE FEEL THAT THE SITUATION STILL
WARRANTS HIGHS THAT ARE SEVERAL DEGREES F OVER THE MODEL CONSENSUS
GIVEN STRONG INSOLATION AND DRY GROUND CONDITIONS. SCHULTZ
.LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE...
NO SIGNIFICANT CHANGES WERE MADE TO THE EXTENDED FORECASTS. THE
CHANCE OF PRECIPITATION ACROSS OUR FORECAST AREA WILL BE GENERALLY
BELOW NORMAL WITH TEMPERATURES WELL ABOVE NORMAL.
A STRONG LOW LEVEL JET WILL BRING HIGHER DEWPOINTS INTO THE FAR
EAST BY FRIDAY AS A RIDGE AXIS PUMPS UP RIGHT THROUGH OUR REGION.
THIS WILL PROVIDE POTENTIAL ENERGY FOR STRONG TO SEVERE STORMS IN
OUR SE ZONES BY LATE FRIDAY...BUT AT THIS TIME BUFKIT SOUNDINGS
CONTINUE TO SHOW A RELATIVELY STRONGLY CAPPED ENVIRONMENT
PREVENTING DEEP CONVECTION. IF THE CAP BREAKS IN OUR FAR EAST I
WOULD EXPECT A SUPERCELL OR TWO DUE TO FAVORABLE VERTICAL
SHEAR...AND THERE IS A WEAK WAVE PROGGED TO MOVE OVER THIS AREA
LATE IN THE DAY DURING MAX HEATING. SO LEFT SLIGHT CHANCE IN THE
FAR EAST AND SOUTHEAST. LOW LEVEL CONVERGENCE ALONG AN INVERTED
SURFACE TROUGH FRIDAY NIGHT MAY ALSO PRODUCE SOME CONVECTION IN
THE CENTRAL ZONES AS WELL. SO WILL CONTINUE THE LOW POPS AS FAR
WEST AS YELLOWSTONE COUNTY FOR THIS PERIOD.
HIGHER DEWPOINTS MAY SPREAD AS FAR WEST AS BILLINGS AT SOME POINT
DURING THE WEEKEND INTO EARLY NEXT WEEK. THIS WILL AGAIN PROVIDE
POTENTIAL ENERGY FOR THUNDERSTORMS...BUT THIS MAY AGAIN BE
LIMITED DUE TO CAPPING ACROSS THE REGION WITH LITTLE EVIDENCE OF
ANY TRIGGER FOR FORCED ASCENT OR ERODING THAT CAP. THEREFORE...AM
INCLINED TO KEEP JUST A SLIGHT CHANCE ACROSS AREAS WITH HIGHER
DEWPOINTS. IN THE MEANTIME...MODELS SUGGEST A DRY INTRUSION OF
AIR IN THE WESTERN SECTIONS THROUGH MUCH OF THE WEEKEND WITH
DOWNSLOPE FLOW DUE TO THE POSITION OF THE SURFACE LOW ON THE
PLAINS. SO LEFT POPS OUT OF THE SW MOUNTAINS AND SURROUNDING AREAS
FOR MUCH OF THE WEEKEND. EARLY NEXT WEEK WE MAY SEE A SIGNIFICANT
EVENT UNFOLD WHERE A COLD FRONT PUSHES THROUGH THE REGION AROUND
TUESDAY NIGHT. THIS MODEST RIDGE CRASHING EVENT MIGHT LEND ITSELF
TO A FIRE WEATHER HIGHLIGHT WITH HOT TEMPERATURES PRECEDING A WIND
SHIFT AND POSSIBLY SOME THUNDERSTORMS ALONG THE COLD FRONT.
SOMETHING WE WILL BE KEEPING A CLOSE EYE ON. BT
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL THE REST OF THE NIGHT ALTHOUGH MID
LEVEL CLOUD COVER IS EXPECTED TO INCREASE. SCATTERED TO ISOLATED
SHOWERS WILL AFFECT KSHR THROUGH 12Z WITH A SLIGHT CHANCE OF
MAINLY IN CLOUD LIGHTNING. SHOWERS WILL THEN INCREASE AGAIN FROM
THE NORTH THIS MORNING. LOOK FOR BRISK NORTHWEST SURFACE WINDS TO
BE COMMON MUCH OF THE DAY. BT
&&
.PRELIMINARY POINT TEMP/POPS...
TDY THU FRI SAT SUN MON TUE
-------------------------------------------------------
BIL 074 047/084 055/087 059/091 062/094 063/094 066/092
3/T 10/U 01/U 22/T 11/B 12/T 22/T
LVM 071 036/082 047/085 052/089 053/091 054/086 057/081
3/T 10/U 01/U 11/U 21/B 12/T 22/T
HDN 075 043/084 052/091 060/094 065/097 063/096 064/096
4/T 10/U 01/U 22/T 11/U 22/T 22/T
MLS 075 047/085 056/087 063/090 064/096 065/095 066/093
4/T 20/U 02/T 22/T 12/T 22/T 22/T
4BQ 074 045/082 055/093 060/090 065/098 066/100 066/094
3/T 20/U 02/T 22/T 11/U 22/T 22/T
BHK 070 045/079 054/085 061/086 061/089 064/093 065/089
3/T 20/U 02/T 22/T 22/T 22/T 22/T
SHR 069 042/080 051/089 061/092 063/095 063/093 062/091
3/T 10/U 01/U 11/U 11/B 22/T 22/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
355 AM CDT WED JUN 20 2012
.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
355 AM CDT WED JUN 20 2012
MAIN FORECAST CONCERNS THIS PACKAGE...SHRA/TSRA CHANCES AND SEVERE
POTENTIAL TODAY/THIS EVENING...SHRA/ISOLATED TSRA CHANCES AGAIN FRI
NIGHT...TEMPERATURES THRU THE PERIOD.
06Z DATA ANALYSIS HAD THE COLD FRONT NORTHWEST OF KDLH TO JUST WEST
OF KFSD. A WEAK WAVE OF LOW PRESSURE WAS RIDING NORTHEAST ALONG THE
FRONT...KEEPING THE FRONT FROM MOVING MUCH EARLY THIS MORNING.
SOUTH OF THE FRONT ACROSS IA/WI/SOUTHERN MN SKIES REMAINED CLEAR
UNDER THE CAPPING AND TEMPS WERE ON THE WARM SIDE...IN THE 70S TO
NEAR 80. CONVERGENCE/MOISTURE FLOW INTO/OVER THE FRONTAL BOUNDARY
PRODUCING A BROAD LINE OF SHRA/TSRA FROM NORTHWEST NEB TO WESTERN LK
SUPERIOR. TRAINING ECHOS IN THE LINE PRODUCING SOME HEAVY RAINS
OF 2 TO AS MUCH AS 5+ INCHES FROM EAST CENTRAL SD TO THE DULUTH
AREA.
20.00Z MODELS LOOK TO HAVE INITIALIZED WELL...BUT FOR GFS AGAIN
SOME 2-7F TOO HIGH WITH SFC DEW POINTS OVER THE MID/UPPER MS VALLEY.
SOLUTIONS QUITE SIMILAR FOR TONIGHT THRU FRI NIGHT AS THE TROUGH
AND COLD FRONT MOVE ACROSS THE REGION EARLY IN THE PERIOD THEN
ANOTHER SHORTWAVE/ROUND OF MOISTURE/LIFT APPROACH LATE IN THE
PERIOD. DPROG/DT OF 500MB HGTS AT 20.00Z SHOWED THE PREVIOUS RUNS OF
THE PAST 24-48HRS VERIFIED RATHER WELL ACROSS NOAM/EASTERN PAC.
OVERALL TREND FAVORS SLOWER OF EARLIER RUNS WITH THE TROUGH/FRONTAL
PASSAGE TODAY/TONIGHT. TREND IS TOWARD SLOWER PROGRESSION OF THE
TROUGH THU/THU NIGHT/FRI WITH BROADER TROUGHING REMAINING OVER THE
GREAT LAKES. MODELS STILL BRING A SHORTWAVE THRU THE EASTERN
ROCKIES/WESTERN PLAINS RIDGING AND TOWARD THE REGION FRI NIGHT BUT
TREND IS WEAKER WITH THIS FEATURE AND PLENTY OF MODEL DETAIL
DIFFERENCES BY 12Z SAT. CHECK OF OBS VS. MODEL DATA AT 06Z SHOWED
MODELS REASONABLE WITH THE COLD FRONT POSITION. MODELS STRUGGLING
WITH THE DEW POINT FIELD OVER THE UPPER MIDWEST SOUTH/EAST OF THE
FRONT...GFS TOO HIGH...GEM/ECMWF A BIT LOW. NAM/GFS TOO FAR SOUTH
WITH THE 00-06Z PRECIP OVER MN/SD...ECMWF/GEM/SREF BETTER. NO CLEAR
MODEL FAVORITE...ESPECIALLY NOT THE GFS WHICH HAS BEEN TOO WET/
WIDESPREAD WITH PRECIP OF LATE. FAVORED A NON-GFS MODEL/ENSEMBLE
BLEND THIS CYCLE. EVEN WITH MODEL ISSUES/DIFFERENCES...SHORT TERM
FCST CONFIDENCE REMAINS AVERAGE TO GOOD THIS CYCLE.
IN THE SHORT TERM...MODEL CONSENSUS CONTINUES TO SLOW THE COLD FRONT
AND SFC-700MB TROUGH PASSAGE...NOW SLOWLY BRINGING IT ACROSS THE
FCST AREA THIS AFTERNOON/EVENING. STRONGEST OF THE SFC-700MB THERMO-
DYNAMIC FORCING...FN CONVERGENCE AND MOISTURE TRANSPORT NOW MOVE
ACROSS THE FCST AREA THIS AFTERNOON AND EVENING. PW VALUES WITH/
AHEAD OF THE FRONT IN THE 1.5 TO 2 INCH RANGE. WITH SOME SUNNY SKIES
THIS MORNING AND THE SLOWER FRONT ARRIVAL...ML/MU CAPE VALUES LIKELY
TO BUILD TO THE HIGHER END OF THE EXPECTED RANGES TODAY. THIS WITH
AN INCREASE OF 0-6KM SHEAR AHEAD OF THE APPROACHING SFC-500MB
TROUGH. SWODY1 LOOKS GOOD FOR THIS AFTERNOON/EVENING. AREA UNDER
FAVORABLE RIGHT ENTRANCE REGION OF A 100+KT 300MB JET MAX. AREA
REMAINS UNDER THIS RIGHT ENTRANCE REGION THRU THIS EVENING. MAIN
CHANGES TO GRIDS TODAY/TONIGHT WERE TO DELAY ARRIVAL OF CONVECTION
THIS MORNING AND EXTEND IT MORE INTO THIS EVENING/TONIGHT.
CONTINUED/RAISED THE AFTERNOON/EVENING RAIN CHANCES INTO THE 70-85
PERCENT RANGE. HEAVY RAINS STILL POSSIBLE THIS AFTERNOON/EVENING
WITH STORM MOTION LOOKING PARALLEL TO THE SLOW MOVING FRONT...MUCH
LIKE OVER EASTERN SD/NORTHERN MN EARLY THIS MORNING. WITH MORE
SUNSHINE THIS MORNING...A WARM START AND SLOWER FRONT ARRIVAL...
RAISED TODAYS HIGHS SOME 4-8F ACROSS THE FCST AREA.
FRONT CONTINUES TO PUSH SOUTH/EAST OF THE FCST AREA THU AS DRIER
HIGH PRESSURE BUILDS EAST FROM THE NORTHERN PLAINS. DEW POINTS FALL
INTO THE 50S FOR THU/FRI FOR WHAT SHOULD BE A STABLE AIRMASS OVER
THE AREA. HOWEVER...COOLER 850-500MB TEMPS BEHIND THE MID LEVEL
TROUGH AXIS AND STEEP LOW LEVEL LAPSE RATES FROM DIURNAL WARMING
LOOK TO PRODUCE SOME 200-500 J/KG OF SB AND ML CAPE ACROSS MAINLY
THE NORTHEAST PARTS OF THE AREA BOTH THU/FRI AFTERNOONS. WITH
POTENTIAL FOR WEAK NORTHWEST FLOW SHORTWAVES TO RIPPLE ACROSS THE
AREA BOTH THU/FRI...CANNOT RULE OUT SOME WIDELY SCATTERED AFTERNOON
SHRA/TSRA EITHER DAY. LEFT THU DRY FOR NOW BUT DID INCLUDE A SMALL
SHRA/TSRA CHANCE OVER THE NORTHEAST END OF THE FCST AREA ON FRI
WHEN A LITTLE STRONGER SHORTWAVE LOOKS RIPPLE ACROSS THE AREA.
EVEN WITH A WEAKER LOOKING SHORTWAVE TO TRACK THRU THE ROCKIES/
WESTERN PLAINS RIDGE AND TOWARD THE AREA FRI NIGHT...ALL STILL
INDICATE A MODEST SURGE OF 850-700MB MOISTURE TRANSPORT/THETA-E
CONVERGENCE TO SPREAD INTO THE AREA LATER FRI NIGHT. LIFTING A
700MB PARCEL OVER THE AREA LATER FRI NIGHT RESULTS IN NEAR NEUTRAL
STABILITY OR VERY WEAK CAPE. CONTINUED A SMALL SHRA/TSRA CHANCE
OVER MAINLY THE WEST/NORTH ENDS OF THE FCST AREA LATE FRI NIGHT
GIVEN THE ELEVATED MOISTURE TRANSPORT/STABILITY SIGNAL.
FAVORED WARMER OF GUIDANCE HIGHS TODAY WITH THE WARM START AND
MORNING SUNSHINE. TRENDED TOWARD A BLEND OF GUIDANCE LOWS/HIGHS FOR
TONIGHT THRU FRI NIGHT.
.LONG TERM...SATURDAY THROUGH TUESDAY
355 AM CDT WED JUN 20 2012
20.00Z MEDIUM RANGE MODELS REMAIN IN RATHER GOOD AGREEMENT WITH EACH
OTHER AND THEIR PREVIOUS RUNS FOR SAT THRU TUE. THE DECENT MODEL
CONSENSUS INDICATES THE FLOW OVER NOAM/EASTERN PAC TO SLOWLY AMPLIFY
WITH DEEPENING TROUGHS NEAR THE COASTS AND BUILDING RIDGING OVER
CENTRAL NOAM. THE RIDGE AXIS TO REMAIN OVER THE PLAINS...WITH THE
UPPER MIDWEST STAYING UNDER NORTHWEST TO NORTH FLOW ALOFT. MOISTURE
IN THE SFC-700MB LAYER CONTINUES TO INCREASE OVER THE AREA SAT AS
THE SHORTWAVE CONTINUES EAST/SOUTHEAST THRU THE RIDGE...ALONG WITH
AN INCREASE OF SB/ML CAPE. 30-50 PERCENT SHRA/TSRA CHANCES STILL
LOOK REASONABLE FOR SAT AND BLEND WELL WITH NEIGHBORING GRIDS. BY
SUN...CAN HIGH PRESSURE AND DRYING IN THE SFC-700MB LAYER BUILD
SOUTH ACROSS THE AREA...AND REMAIN OVER THE AREA FOR EARLY NEXT
WEEK. WITH THE NORTHWEST/NORTH FLOW ALOFT AND/OR CAN HIGH PRESSURE
BUILDING IN...TEMPS FOR SAT THRU TUE TRENDING TO BE NEAR TO A BIT
BELOW NORMAL. THIS WELL TRENDED IN THE DAY 4-7 GRIDS BY THE
MODEL/ENSEMBLE CONSENSUS DATA SET.
&&
.AVIATION...THROUGH 06Z THURSDAY
1147 PM CDT TUE JUN 19 2012
FRONTAL BOUNDARY HAS BEEN NEARLY STATIONARY FROM CENTRAL MN...INTO
NORTHERN WI. CONVECTION CONTINUES TO THE NORTH OF THE BOUNDARY
WITH CLEAR SKIES TO THE SOUTH. TAF SITES WILL REMAIN VFR THROUGH THE
OVERNIGHT HOURS AND REMAIN IN THE WARM SECTOR. FRONT THEN BEGINS TO
MOVE WEDNESDAY AND CONVECTION WILL BECOME MORE LIKELY AS THE DAY
WEARS ON. 20.00Z HRRR DOES SHOW SHOWERS APPROACHING THE KRST SITE
AROUND 15Z WEDNESDAY. EXPECT CEILINGS TO LOWER...BUT REMAIN VFR
AHEAD OF THE FRONT. MAIN CONVECTION LIKELY AFTER 18Z THOUGH AND THEN
INTO THE EVENING HOURS WITH FRONTAL PASSAGE EXPECTED 00Z-02Z AT KRST
AND 01-03Z AT KLSE. MODELS SUGGEST SOME STRATUS BEHIND THE FRONT AND
DID LOWER INTO MVFR CATEGORY AT BOTH SITES AFTER FRONTAL PASSAGE.
&&
.HYDROLOGY...WED/WED EVENING
355 AM CDT WED JUN 20 2012
ONE LAST ROUND OF STORMS LATE TODAY INTO TONIGHT AS THE COLD FRONT
MAKES ITS WAY ACROSS THE REGION. AMPLE INSTABILITY AND SUPPLY OF
WARM MOIST AIR FOR HEAVY RAINFALL PRODUCTION. PRECIPITABLE WATER
POOLS JUST OVER 2 INCHES ALONG THE SLOW-MOVING BOUNDARY. INDIVIDUAL
CELLS WILL HAVE A GOOD NORTHEAST MOVEMENT...BUT WITH THE FRONT ONLY
CRAWLING FORWARD...POSSIBILITY FOR TRAINING OF CELLS IS REAL. RAIN
AMOUNTS OF 2-4 INCHES NOT OUT OF THE QUESTION FOR SOME SPOTS...WITH
A BROAD AREA AROUND 1 INCH SEEMINGLY LIKELY.
SOME BASINS ARE STILL WET AND/OR HAVE RIVER LEVELS RUNNING HIGH...
INCLUDING THE ZUMBRO...BLACK...BUFFALO...TREMPEALEAU...AND
MISSISSIPPI. SO WILL HAVE TO KEEP AN EYE ON THINGS. LATEST RIVER
FORECASTS INDICATE THE MISSISSIPPI WILL RISE TO NEAR FLOOD STAGE
AGAIN AT WABASHA...WHICH MEANS OTHER SITES ALONG THE BIG MUDDY WILL
REACH HEIGHTS VERY SIMILAR TO WHAT WAS SEEN JUST LAST WEEK.
WITH THAT IN MIND...WILL SEND A HYDROLOGIC OUTLOOK /ESFARX/ TO
HEIGHTEN THE PUBLIC AWARENESS OF THE SITUATION.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
355 AM CDT WED JUN 20 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RRS
LONG TERM....RRS
AVIATION.....RABERDING
HYDROLOGY....MW
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1147 PM CDT TUE JUN 19 2012
.SHORT TERM /TONIGHT THROUGH FRIDAY/...
MAIN CONCERNS THIS PERIOD WILL BE THE THE PASSAGE OF THE FRONT ON
WEDNESDAY AND ASSOCIATED CHANCES FOR THUNDER AND HEAVY RAINFALL.
FRONT HAS SLOWED SOMEWHAT AND WITH UPPER LEVEL WINDS BECOMING MORE
PARALLEL TO BOUNDARY...EXPECTATIONS ARE FOR A LATER ARRIVAL OF
THUNDER MORE TOWARD 12Z WED NORTHWEST SECTIONS RATHER THAN 06Z. BY
MORNING WILL SEE INCREASE IN AREAL COVERAGE AS THUNDER ACTIVITY FROM
CENTRAL MN WORKS EAST IN THE SLOWING FLOW. AS THE H500 TROUGH SWINGS
EAST WEDNESDAY WILL SEE RAPID INCREASE IN STORM DEVELOPMENT FROM
WEST TO EAST IN THE AFTERNOON HOURS. HAVE CONTINUED HIGHEST POP AT
THAT TIME WITH HIGH LIKELY CAT EXPECTED. STORM MOTION EXPECTED TO BE
RATHER BRISK TO THE NORTHEAST AT 25 TO 35KTS. CORFIDI VECTORS
SUGGEST OVERALL NORTHEAST MOVEMENT. SEVERE CHANCES WILL BE LIMITED
WITH SOME EARLY DAY CONVECTION DEBRIS LIKELY TO REDUCE DAYTIME
HEATING SOMEWHAT...BUT LINEAR WIND FIELDS INCREASING OVERNIGHT
TONIGHT AND WED MORNING MAY BE ENOUGH TO PRODUCE SOME ISO SEVERE
STORMS DURING THE AFTERNOON HOURS...MAINLY FOR WIND OR HAIL. THE
FRONT WILL MOVE EAST QUICKLY WEDNESDAY NIGHT WITH CLEARING EXPECTED
TO TAKE OVER FOR THE REMAINDER OF WED NIGHT. THURSDAY LOOKS
UNEVENTFUL BUT THERE IS A HINT OF A SHORT WAVE TRACKING SOUTHEAST
EITHER LATE THURSDAY EVENING OR FRIDAY. CONSENSUS IN MODELS LACKING
SO HAVE KEPT POP AT 14 FOR NOW THURSDAY NIGHT AND FRIDAY. NEXT
UPSTREAM WAVE EXPECTED TO ARRIVE ON FRIDAY NIGHT AS RETURN FLOW AND
STRONGER WARM AIR ADVECTION BEGINS TO INCREASE INSTABILITY AND
ISENTROPIC LIFT ACROSS THE REGION.
.LONG TERM...SATURDAY THROUGH TUESDAY
LEE SIDE TROUGH QUICKLY DEEPENS SATURDAY MORNING TO OUR WEST AND
INCREASING SFC MOISTURE CONVERGENCE ALONG WITH LIFT AT H700-H850
WILL RESULT IN MCS OR WIDESPREAD ELEVATED THUNDER EVENT. POP HAS
BEEN MAINTAINED ACROSS THE REGION WITH THE HIGHER POP WEST...THOUGH
MODELS AGAIN HAVING SOME DIFFICULTY WITH THE TIMING...PREFER THE
SLIGHTLY SLOWER EURO MODEL OVER THE GFS SOLUTION. HIGHS ON SATURDAY
WILL BE APPRECIABLY COOLER...AND MAY NOT HAVE TRIMMED HIGHS ENOUGH
IF CONVECTION ENDS UP AS WIDESPREAD AS INDICATED...HIGHS MAY
STRUGGLE TO REACH THE LOWER TO MID 70S...SOME 5 DEGREES COOLER THAN
NOW FORECAST. WILL NEED TO MONITOR TRENDS OVER NEXT FEW DAYS. FRONT
HANGS ON INTO SUNDAY AND THEN SAGS BACK SOUTH AS CANADIAN HIGH
BUILDS INTO THE REGION FROM THE NORTHWEST. WITH MODIFIED NORTHWEST
FLOW...EXPECT TO SEE GENERALLY PLEASANT HIGHS RETURN TO THE REGION
MONDAY AND TUESDAY WITH DRY WEATHER...HIGHS REACHING THE 70S TO
LOWER 80S.
&&
.AVIATION...THROUGH 06Z THURSDAY
1147 PM CDT TUE JUN 19 2012
FRONTAL BOUNDARY HAS BEEN NEARLY STATIONARY FROM CENTRAL
MINNESOTA...INTO NORTHERN WISCONSIN. CONVECTION CONTINUES TO THE
NORTH OF THE BOUNDARY WITH CLEAR SKIES TO THE SOUTH. TAF SITES
WILL REMAIN VFR THROUGH THE OVERNIGHT HOURS AND REMAIN IN THE WARM
SECTOR. FRONT THEN BEGINS TO MOVE WEDNESDAY AND CONVECTION WILL
BECOME MORE LIKELY AS THE DAY WEARS ON. 20.00Z HRRR DOES SHOW
SHOWERS APPROACHING THE KRST SITE AROUND 15Z WEDNESDAY. EXPECT
CEILINGS TO LOWER...BUT REMAIN VFR AHEAD OF THE FRONT. MAIN
CONVECTION LIKELY AFTER 18Z THOUGH AND THEN INTO THE EVENING HOURS
WITH FRONTAL PASSAGE EXPECTED 00Z-02Z AT KRST AND 01-03Z AT KLSE.
MODELS SUGGEST SOME STRATUS BEHIND THE FRONT AND DID LOWER INTO
MVR CATEGORY AT BOTH SITES AFTER FRONTAL PASSAGE.
&&
.HYDROLOGY...WED/WED EVENING
RECAP OF PREVIOUSLY ISSUED HYDRO DISCUSSION FROM MORNING...
ANOTHER ROUND OF STORMS...WEDNESDAY...WILL MAINTAIN AT LEAST THE
POSSIBILITY FOR HEAVY RAINFALL AND POTENTIAL FLOODING CONCERNS.
ANOTHER BATCH OF STORMS IS ANTICIPATED ON WEDNESDAY AS A POTENT
SHORT WAVE TROUGH AND ASSOCIATED COLD FRONT MOVE THROUGH THE REGION.
ATMOSPHERE WILL REMAIN MOIST AND UNSTABLE...WITH AMPLE MOISTURE AND
WARM CLOUD DEPTH FOR THE PRODUCTION OF HEAVY RAINFALL. THE KEY HERE
WILL BE HOW FAST THE FRONT MOVES THROUGH. TROUGH IS DEEPENING AND
SHOWING SIGNS OF BECOMING NEGATIVELY TILTED PER THE MODEL
FORECASTS...AND THIS MAY SLOW THE FRONTAL MOVEMENT SOMEWHAT. STORMS
WILL HAVE A GOOD NORTHEAST FORWARD MOTION...BUT MAY SEE SOME
TRAINING OF STORMS ALONG THE SOUTHWEST TO NORTHEAST FRONTAL
BOUNDARY. SOME RIVERS ARE RUNNING HIGH /ZUMBRO...BLACK...BUFFALO...
TREMPEALEAU...MISSISSIPPI/ SO WILL HAVE TO WATCH WHERE THE HEAVIEST
RAIN FALLS FOR ANY FLOOD POTENTIAL.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...REV
LONG TERM....REV
AVIATION...RABERDING
HYDROLOGY....MW
AREA FORECAST DISCUSSION
NWS DENVER CO
407 AM MDT WED JUN 20 2012
.SHORT TERM...COLD FRONT HAS PUSHED SOUTH ACROSS THE PLAINS WITH
LOW LEVEL MOISTURE INCREASING AND DEWPOINTS RISING INTO THE 40S
AND LOWER 50S. LATEST MSAS ANALYSIS SHOWS BEST PRESSURE RISE
CENTER PUSHING THROUGH WESTERN NEBRASKA...HELPING LOW LEVEL WINDS
TURN A BIT NORTHEASTERLY ACROSS THE PLAINS. LOOKS LIKE SHORT RANGE
MESOSCALE MODELS INCLUDING THE HRRR HAVE THE BEST HANDLE ON THIS
LOW LEVEL MOISTURE AND COOLER AIR AT THIS TIME...ALTHOUGH EVEN THE
NAM AND GFS SUGGEST THE SAME SCENARIO JUST WITHOUT THE HIGHER
RESOLUTION. NONETHELESS...THERE WILL BE A VERY SHARP LINE OF
SINGLE DIGIT DEWPOINTS OVER THE HIGH COUNTRY BATTLING UPPER 30S
AND 40S DEWPOINTS BACKING INTO THE FOOTHILLS AND PORTIONS OF
SOUTH PARK DURING THE DAY. THE INCREASE IN LOW LEVEL MOISTURE AND
UPSLOPE FLOW WILL ALSO AID STRATUS FORMATION ACROSS THE PLAINS AND
PERHAPS LOWER FOOTHILLS EARLY THIS MORNING.
TEMPERATURES WILL BE A GOOD 20 DEGREES COOLER ACROSS THE PLAINS
AND FOOTHILLS TODAY WITH THE RATHER STRONG AND DEEP COLD
ADVECTION. EVEN IN THE MOUNTAINS...GRIDDED TEMP FIELDS SHOW ABOUT
10-16 DEGREES COOLING. AIRMASS WILL BE TOO COOL IN THE LOW LEVEL
TO SUPPORT ANY CONVECTION...ALTHOUGH CANT TOTALLY RULE OUT A
SHOWER OR STORM IN THE PARK COUNTY AREA BY THIS EVENING WITH
ENOUGH MOISTURE POOLING THERE AND SLIGHTLY WEAKER CAP. PARTIAL
CLEARING LATER TONIGHT SHOULD ALLOW FOR A PLEASANTLY COOL NIGHT
FOR A CHANGE.
.LONG TERM...COOL TEMPERATURES...OR AT LEAST TEMPERATURES AROUND
SEASONAL NORMALS WILL HANG ON FOR ONE MORE DAY THURSDAY AS
SOUTHEASTERLY LOW LEVEL FLOW CONTINUES ACROSS EASTERN COLORADO.
MODERATE DEW POINTS WILL ALSO REMAIN ON THE PLAINS...HELPING TO
KEEP TEMPERATURES FROM WARMING TOO RAPIDLY. EVEN THOUGH SOME LOW
LEVEL MOISTURE WILL BE IN PLACE OVER THE REGION...STRONG
SUBSIDENCE AT MID LEVELS ASSOCIATED WITH RISING HEIGHTS OVER THE
STATE WILL KEEP MOST CONVECTION CAPPED. MODELS ARE VERY SKIMPY IN
PRODUCING ANY QPF THURSDAY AFTERNOON AND EVENING. AFTER
THURSDAY...THE UPPER RIDGE STRENGTHENS OVER THE SOUTH CENTRAL
UNITED STATES WITH COLORADO UNDER WARM SOUTHWESTERLY FLOW ALOFT.
WARM TEMPERATURES OUT OF THE DESERT SOUTHWEST WILL ONCE AGAIN
ADVECT ACROSS OUR REGION. MOS TEMPERATURE GUIDANCE POPS
TEMPERATURES INTO THE MID AND UPPER 90S FOR THE FRIDAY THROUGH
THE WEEKEND AND INTO EARLY NEXT WEEK. OPPORTUNITIES FOR ANY
PRECIPITATION WILL BE SPARSE AS THE STATE REMAINS CUT OFF FROM ANY
MOISTURE SOURCES. THE GFS AND ECMWF HINT AT A PLUME OF MOISTURE
ARCING ACROSS ARIZONA INTO UTAH NEXT TUESDAY...BUT THIS WOULD BE
TOO FAR WEST TO BRING ANY BENEFICIAL RAIN INTO COLORADO. WARM
TEMPERATURES AND LOW HUMIDITIES WILL CONTINUE TO PRESENT PROBLEMS
FOR FIRE MANAGERS WITH NO REAL RELIEF IN SIGHT.
&&
.AVIATION...TEMPERATURE/DEWPOINT SPREADS WILL NARROW EARLY THIS
MORNING AND WITH CONTINUED UPSLOPE FLOW EXPECT A FAIRLY LOW
STRATUS DECK TO DEVELOP IN THE 11Z-15Z TIME FRAME WITH IFR
CONDITIONS POSSIBLE. CEILINGS WILL LIKELY GRADUALLY LIFT BUT
INSTRUMENT LANDINGS MAY STILL BE REQUIRED THROUGH 18Z WITH
CONTINUED UPSLOPE FLOW SLOWING STRATUS DISSIPATION. BUT OVERALL
EXPECT A GRADUAL LIFT/BREAKUP FROM 16Z-19Z WITH DAYTIME HEATING.
THERE ARE INDICATIONS OF A 6000-7000 FT AGL CEILING REDEVELOPING
AROUND 00Z-02Z AS UPSLOPE MOISTURE GETS TRAPPED UNDER A STRONG
CAPPING INVERSION.
.FIRE WEATHER...THERE WILL BE A VERY SHARP DIVIDE IN A MOIST
AIRMASS BACKING INTO THE FOOTHILLS AND PARK COUNTY TODAY VERSUS
MUCH DRIER AIR REMAINING OVER MUCH OF GRAND AND SUMMIT COUNTIES
THROUGH THE DAY. AT THIS TIME...WE DO EXPECT A MORE EAST/SOUTHEAST
MOIST FLOW TO DEVELOP IN BOTH THE HIGH PARK AND SPRINGER FIRE
AREAS THIS MORNING PER THE HRRR...ALTHOUGH THE SPRINGER FIRE COULD
VERY WELL WOBBLE BETWEEN THE TWO AIRMASSES BEFORE THE DEEPER MOIST
AIRMASS FINALLY WINS OUT LATER THIS AFTERNOON. WE WILL BE CLOSE TO
RED FLAG CONDITIONS IN PORTIONS OF SUMMIT...GRAND...AND WESTERN
PARK COUNTIES WHERE THE VERY DRY ARIMASS AND LOW HUMIDITY
READINGS PREVAIL. HOWEVER...WINDS SHOULD BE SLIGHTLY WEAKER THAN
THE LAST COUPLE DAYS.
&&
.HYDROLOGY...NO CONCERNS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BARJENBRUCH
LONG TERM....DANKERS
AVIATION...BARJENBRUCH
AREA FORECAST DISCUSSION
NWS JACKSON KY
1136 AM EDT WED JUN 20 2012
.UPDATE...
ISSUED AT 1136 AM EDT WED JUN 20 2012
12Z NAM AND HRRR CONTINUE TO POINT TOWARDS CONVECTION INITIATING
ALONG THE HIGHER TERRAIN NEAR THE VA BORDER EARLY THIS AFTERNOON WITH
A SLIGHT CHANCE FURTHER NW BY MID TO LATE AFTERNOON. THE 09Z SREF
ALSO SUPPORTING THIS. 1515Z VISIBLE SATELLITE SHOWS CU FORMING OVER
THE BLACK MOUNTAIN AREA OF HARLAN COUNTY WITH CU EXTENDING ON INTO
WISE COUNTY VA...SO FORECAST LOOKS ON TRACK AT THIS POINT. MADE MINOR
UPDATE TO NDFD FOR LATEST OBSERVATIONAL TRENDS.
UPDATE ISSUED AT 953 AM EDT WED JUN 20 2012
HAVE UPDATED NDFD AND ASSOICATED PRODUCTS TO EXPAND THE 20 PERCENT
CHANCE OF THUNDERSTORMS ACROSS THE FORECAST AREA FOR THIS AFTERNOON.
THIS IDEA IS SUPPORTED BY THE 06Z NAM AND 10Z HRRR. CONVECTION MAY
FIRST INITIATE ALONG THE HIGHER TERRAIN NEAR THE VA BORDER IN EARLY
AFTERNOON...WITH THE ISOLATED CONVECTION THEN BECOMING POSSIBLE
FURTHER NW DURING THE MIDDLE TO LATE AFTERNOON.
UPDATE ISSUED AT 659 AM EDT WED JUN 20 2012
SOME PATCHY FOG SHOWING UP IN A FEW OBSERVATIONS WITH VISIBILITIES IN
THE 5-6 MILE RANGE. FOG ALREADY MENTIONED IN THE FORECAST. TEMPS ON
TRACK AND GRIDS HAVE BEEN REFRESHED FOR THE MOST RECENT OBS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 250 AM EDT WED JUN 20 2012
SFC AND 50H HIGH OVER THE APPALACHIANS WILL SHIFT TO THE COAST AS A
COLD FRONT APPROACHES THE OHIO VALLEY. THE RIDGE WILL BE REPLACED BY
A 50H TROF FROM THE GREAT LAKES TO FLA. MODELS WERE IN GOOD AGREEMENT
THAT THE FRONT WOULD ENTER EASTERN KY EARLY FRIDAY WITH THE BULK OF
THE PCPN EXPECTED WITH AND BEHIND THE FRONT. SEVERAL DAYS OF
SOUTHWEST FLOW HAS PUSHED DEWPOINTS INTO THE UPPER 60S AS EVIDENCED
BY NIGHTLY VALLEY FOG. WITH THE APPROACHING FRONT EXPECT AN INCREASE
IN AFTERNOON SHOWERS AND THUNDERSTORMS ACROSS THE FORECAST AREA.
THESE STORMS WILL BE INITIALLY LOCATED IN THE EASTERN COUNTIES THIS
AFTERNOON AND THEN MORE WIDESPREAD ON THU BEFORE THE FRONT ARRIVES ON
FRIDAY. TEMPERATURES HAVE BEEN HARD PRESSED TO RISE MUCH ABOVE THE 90
DEG MARK WITH ALL THE GREEN FORESTS IN EASTERN KY. EXPECT THIS TREND
TO CONTINUE WITH HIGHS IN THE UPPER 80S TO AROUND 90 BOTH TODAY AND
THU BEFORE FALLING SLIGHTLY TO JUST THE UPPER 80S ON FRI WITH THE
INCREASE IN CLOUD COVER PRECEEDING THE FRONTAL BOUNDARY. OVERNIGHT
LOWS WILL FALL TO AROUND 70 EACH NIGHT WITH LOWER 70S PREVALENT ON
THE RIDGES AS THE COOLER AIR SINKS INTO THE VALLEYS AFTER SUNSET.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 258 AM EDT WED JUN 20 2012
THE EXTENDED FORECAST PERIOD BEGINS ON FRIDAY NIGHT WITH MERIDIONAL
AND UNSEASONAL AMPLIFIED PATTERN FOR THIS TIME OF YEAR. A
STRENGTHENING RIDGE DEVELOPS OVER THE CENTRAL PLAINS AS BROAD TROUGH
TAKES SHAPE OVER THE EASTERN CONUS AND ALONG THE CANADIAN MARITIMES.
A DEVELOPED AND STRENGTHENING CLOSED LOW OVER THE HUDSON BAY REGION
WILL SEND DOWN SEVERAL SHORTWAVES DURING THE REST OF THE EXTENDED.
AFTER A BRIEF SHORTWAVE RIDGE ON SATURDAY...A STRONGER SHORTWAVE
TROUGH DIVES SOUTH THROUGH THE DAKOTAS AND MN INTO THE OHIO VALLEY
BY SUNDAY. BY TUESDAY...THE CLOSED LOW OVER THE GREAT LAKES FINALLY
DROPS SOUTH INTO THE MID ATLANTIC AND NEW ENGLAND STATES BUT REMAINS
NEARLY STATIONARY THROUGH THE END OF THE EXTENDED AS A BLOCKING
PATTERN LOOKS TO SET UP.
THE INITIALIZATION CAME IN WITH A REASONABLE SET UP FOR POPS WITH
SOME SLIGHT CHANCE IN THE EASTERN COUNTIES BORDERING VA WITH THE
EXITING FRONT FRIDAY NIGHT. THE NEXT FRONT WILL MOVE THROUGH ON
SUNDAY PROVIDING A SLIGHT CHANCE OF PRECIP. WHILE THE FORCING AND
INSTABILITY ARE THERE...ONCE AGAIN THE AMOUNT OF MOISTURE IS OF A
CONCERN AS SOME SHOWER AND THUNDERSTORM ACTIVITY WILL DEVELOP FOR
SUNDAY THROUGH MONDAY...BUT COVERAGE WILL BE FEW AND FAR BETWEEN
COMPLICATING THE DRY CONDITIONS THAT HAVE DEVELOPED IN CERTAIN AREAS
OF EASTERN KENTUCKY. BY TUESDAY...GOOD SUBSIDENCE AND DRY MID LEVELS
HAVE EDGED FAR ENOUGH EAST TO BASICALLY KEEP PRECIP OUT OF EASTERN
KENTUCKY FOR THE REST OF THE EXTENDED AND POSSIBLY EVEN LONGER PAST
DAY 7. BY TUESDAY...THE AFOREMENTIONED UPPER LEVEL CLOSED LOW SLIDES
SOUTH AS A COLD FRONT PUSHES SOUTH THROUGH THE OHIO VALLEY.
HOWEVER...THIS LOOKS TO BE A DRY FRONT AS THE BULK OF THE MOISTURE
AND BETTER DYNAMICS STAYS TO THE NORTH AND EAST PROLONGING THE DRY
PERIOD OVER THE FA. ON A GOOD NOTE...THE PROLONGED TROUGH OVER THE
EASTERN CONUS CUTS OFF THE FLOW FROM THE SOUTH AND INTO A MORE
NORTHWEST FLOW. THIS PUTS HIGH TEMPERATURES ACROSS THE AREA RIGHT
AROUND NORMAL IN THE LOW 80S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 703 AM EDT WED JUN 20 2012
LOCALIZED FOG HAS DEVELOPED IN DEEP VALLEYS AND SHOULD PERSIST
THROUGH ABOUT 13Z. MAY BE BRIEF PERIODS OF MVFR AT LOZ/SME BUT
SHOULD LAST ONLY A FEW MINUTES AT A TIME AND DO NOT PLAN TO CHANGE
THE TAF TO INDICATE THE FOG. IT WILL BE THICKEST AND MOST PREVALENT
IN THE BIG SANDY RIVER VALLEY BUT THIS WILL NOT AFFECT ANY AIRPORTS
AS THEY ARE LOCATED ON RIDGETOPS IN THIS AREA. ISOLATED CONVECTION
MAY DEVELOP SOUTHEAST OF THE TAF SITES BETWEEN 18Z AND 23Z.
HOWEVER...VFR CONDITIONS ARE EXPECTED THROUGHOUT THE PERIOD AT THE
TAF SITES. THE LOCATION OF ANY CONVECTION WILL NEED TO BE MONITORED
FOR POSSIBLE INCLUSION OF MVFR FOG THURSDAY MORNING.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...DUSTY
LONG TERM....SHALLENBERGER
AVIATION...DUSTY
AREA FORECAST DISCUSSION
NWS BILLINGS MT
611 AM MDT WED JUN 20 2012
.SHORT TERM...VALID FOR TDY AND THU...
WE MADE A MINOR UPDATE TO THE MORNING FORECAST BASED ON THE TRENDS
IN RECENT RADAR DATA IN ORDER TO BUMP POPS UP TO AROUND 50 PERCENT
FOR PLACES LIKE BILLINGS AND MILES CITY. INSTEAD OF JUST USING THE
PROBABILITY IN THE UPDATED FORECAST...WE ADDED COVERAGE /SCATTERED
SHOWER/ WORDING TO HELP CONVEY THE TRENDS IN PRECIPITATION. ALL OF
THIS IS SUPPORTED BY THE LATEST RAP AND HRRR SIMULATIONS. SCHULTZ
PREVIOUS DISCUSSION...ISSUED AT 341 AM MDT WED JUN 20 2012...
AFTER ONE MORE OPPORTUNITY FOR SHOWERS OR PERHAPS A STORM TODAY...
A WARM AND MAINLY DRY PERIOD WILL START THU AS HEIGHTS RISE ALOFT.
MOISTURE CHANNEL IMAGERY AT 09 UTC REVEALS A BIT MORE COMPLEX FLOW
THAN WE EXPECTED AT THIS TIME YESTERDAY...WITH AN ADDITIONAL SHORT
WAVE MOVING INTO WESTERN WY. THAT FEATURE HAS BEEN RESPONSIBLE FOR
SHOWERS OVER SOUTH CENTRAL MT OVERNIGHT...BUT SINCE BOTH THAT WAVE
AND ITS MORE NORTHERN COUNTERPART WILL BE HEADING EAST OF MT TODAY
WE WILL MAINLY DEAL WITH LINGERING CYCLONIC FLOW IN THEIR WAKE.
TODAY...WEAK CONVECTION IS EXPECTED IN CYCLONIC FLOW ALOFT...WHICH
SUPPORTS POPS IN THE 30 PERCENT RANGE FOR MOST AREAS. A BIT BETTER
CONCENTRATION OF CONVECTION COULD OCCUR ON THE LEADING EDGE OF THE
SUBTLE 1.5 PVU LOWERING THAT THE 00 UTC NAM AND GFS TAKE FROM NEAR
GREAT FALLS AT 09 UTC TO MILES CITY BY 18 UTC. SHOWERS AROUND THAT
FEATURE HAVE HELD TOGETHER IN NORTH CENTRAL MT OVERNIGHT DESPITE A
STABLE BOUNDARY LAYER...WHICH ADDS CONFIDENCE TO OUR BELIEF THAT A
SCATTERING OF CONVECTION WILL OCCUR ACROSS OUR AREA TODAY. THAT IS
FURTHER SUPPORTED BY THE LAST FEW HRRR RUNS...AND THE QPF FROM THE
00 UTC GFS AND NAM AS WELL. THE FORECAST DOES CONTAIN A MENTION OF
THUNDERSTORMS TOO...WITH THE CALIBRATED PROBABILITIES OF THAT FROM
THE 21 UTC SREF NEAR 10 PERCENT. HOWEVER...FORECAST SOUNDINGS SHOW
MARGINAL BUOYANCY...AND SOME HINTS OF MID-LEVEL SUBSIDENCE...WHICH
SHOULD KEEP MOST UPDRAFTS FROM GROWING TALL ENOUGH FOR TOO MUCH IN
THE WAY OF LIGHTNING PRODUCTION. IT IS ALSO POSSIBLE THAT DOWNWARD
MOTION WILL RESULT IN LOWER-THAN-EXPECTED CONVECTIVE COVERAGE OVER
PARTS OF THE AREA.
TONIGHT...WE CONTINUED SOME SLIGHT CHANCE POPS FOR SOUTHEASTERN MT
UNTIL 03 UTC IN ORDER TO GIVE ANY RESIDUAL CONVECTION TIME TO END.
THIS IS SUPPORTED BY THE 00 UTC 4 KM WRF-NMM...WHICH DOES NOT TAIL
OFF ALL OF ITS WEAK CONVECTION NEAR MILES CITY AND BAKER UNTIL THE
LATE EVENING HOURS. WEAK SURFACE RIDGING WILL INFLUENCE THE REGION
OVERNIGHT...WHICH SHOULD ALLOW FOR DECENT RADIATIONAL COOLING. OUR
FORECAST LOWS ARE ON THE COLD SIDE OF THE GUIDANCE SPREAD BASED ON
THE DRY BOUNDARY LAYER AIR AND LIGHT WINDS NEAR THE RIDGE. THE AIR
MASS IS NOT VERY COOL THOUGH...SO WE MAY ADMITTEDLY BE TOO COLD IN
SPOTS. NONETHELESS...NAM-BASED GUIDANCE HANDLED A SIMILAR SCENARIO
LAST FRI NIGHT WELL...SO WE LEANED ON IT FOR LOWS TONIGHT AS WELL.
THU...WARM AIR ADVECTION WILL OCCUR AS HEIGHTS ALOFT BEGIN RISING.
THE LOWER AND MIDDLE 80S F WILL BE AN EASY TARGET ON THE PLAINS AS
MIXING TO 700 HPA OCCURS. EVEN THOUGH THERE WILL BE LIGHT EASTERLY
LOW-LEVEL FLOW IN THE AFTERNOON...WE FEEL THAT THE SITUATION STILL
WARRANTS HIGHS THAT ARE SEVERAL DEGREES F OVER THE MODEL CONSENSUS
GIVEN STRONG INSOLATION AND DRY GROUND CONDITIONS. SCHULTZ
.LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE...
NO SIGNIFICANT CHANGES WERE MADE TO THE EXTENDED FORECASTS. THE
CHANCE OF PRECIPITATION ACROSS OUR FORECAST AREA WILL BE GENERALLY
BELOW NORMAL WITH TEMPERATURES WELL ABOVE NORMAL.
A STRONG LOW LEVEL JET WILL BRING HIGHER DEWPOINTS INTO THE FAR
EAST BY FRIDAY AS A RIDGE AXIS PUMPS UP RIGHT THROUGH OUR REGION.
THIS WILL PROVIDE POTENTIAL ENERGY FOR STRONG TO SEVERE STORMS IN
OUR SE ZONES BY LATE FRIDAY...BUT AT THIS TIME BUFKIT SOUNDINGS
CONTINUE TO SHOW A RELATIVELY STRONGLY CAPPED ENVIRONMENT
PREVENTING DEEP CONVECTION. IF THE CAP BREAKS IN OUR FAR EAST I
WOULD EXPECT A SUPERCELL OR TWO DUE TO FAVORABLE VERTICAL
SHEAR...AND THERE IS A WEAK WAVE PROGGED TO MOVE OVER THIS AREA
LATE IN THE DAY DURING MAX HEATING. SO LEFT SLIGHT CHANCE IN THE
FAR EAST AND SOUTHEAST. LOW LEVEL CONVERGENCE ALONG AN INVERTED
SURFACE TROUGH FRIDAY NIGHT MAY ALSO PRODUCE SOME CONVECTION IN
THE CENTRAL ZONES AS WELL. SO WILL CONTINUE THE LOW POPS AS FAR
WEST AS YELLOWSTONE COUNTY FOR THIS PERIOD.
HIGHER DEWPOINTS MAY SPREAD AS FAR WEST AS BILLINGS AT SOME POINT
DURING THE WEEKEND INTO EARLY NEXT WEEK. THIS WILL AGAIN PROVIDE
POTENTIAL ENERGY FOR THUNDERSTORMS...BUT THIS MAY AGAIN BE
LIMITED DUE TO CAPPING ACROSS THE REGION WITH LITTLE EVIDENCE OF
ANY TRIGGER FOR FORCED ASCENT OR ERODING THAT CAP. THEREFORE...AM
INCLINED TO KEEP JUST A SLIGHT CHANCE ACROSS AREAS WITH HIGHER
DEWPOINTS. IN THE MEANTIME...MODELS SUGGEST A DRY INTRUSION OF
AIR IN THE WESTERN SECTIONS THROUGH MUCH OF THE WEEKEND WITH
DOWNSLOPE FLOW DUE TO THE POSITION OF THE SURFACE LOW ON THE
PLAINS. SO LEFT POPS OUT OF THE SW MOUNTAINS AND SURROUNDING AREAS
FOR MUCH OF THE WEEKEND. EARLY NEXT WEEK WE MAY SEE A SIGNIFICANT
EVENT UNFOLD WHERE A COLD FRONT PUSHES THROUGH THE REGION AROUND
TUESDAY NIGHT. THIS MODEST RIDGE CRASHING EVENT MIGHT LEND ITSELF
TO A FIRE WEATHER HIGHLIGHT WITH HOT TEMPERATURES PRECEDING A WIND
SHIFT AND POSSIBLY SOME THUNDERSTORMS ALONG THE COLD FRONT.
SOMETHING WE WILL BE KEEPING A CLOSE EYE ON. BT
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL THE REST OF THE NIGHT ALTHOUGH MID
LEVEL CLOUD COVER IS EXPECTED TO INCREASE. SCATTERED TO ISOLATED
SHOWERS WILL AFFECT KSHR THROUGH 12Z WITH A SLIGHT CHANCE OF
MAINLY IN CLOUD LIGHTNING. SHOWERS WILL THEN INCREASE AGAIN FROM
THE NORTH THIS MORNING. LOOK FOR BRISK NORTHWEST SURFACE WINDS TO
BE COMMON MUCH OF THE DAY. BT
&&
.PRELIMINARY POINT TEMP/POPS...
TDY THU FRI SAT SUN MON TUE
-------------------------------------------------------
BIL 074 047/084 055/087 059/091 062/094 063/094 066/092
5/T 10/U 01/U 22/T 11/B 12/T 22/T
LVM 071 036/082 047/085 052/089 053/091 054/086 057/081
3/T 10/U 01/U 11/U 21/B 12/T 22/T
HDN 075 043/084 052/091 060/094 065/097 063/096 064/096
5/T 10/U 01/U 22/T 11/U 22/T 22/T
MLS 075 047/085 056/087 063/090 064/096 065/095 066/093
5/T 20/U 02/T 22/T 12/T 22/T 22/T
4BQ 074 045/082 055/093 060/090 065/098 066/100 066/094
4/T 20/U 02/T 22/T 11/U 22/T 22/T
BHK 070 045/079 054/085 061/086 061/089 064/093 065/089
3/T 20/U 02/T 22/T 22/T 22/T 22/T
SHR 069 042/080 051/089 061/092 063/095 063/093 062/091
3/T 10/U 01/U 11/U 11/B 22/T 22/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
920 AM EDT WED JUN 20 2012
.SYNOPSIS...
STRONG RIDGE OF HIGH PRESSURE OVER THE OHIO VALLEY WILL MOVE OFF THE
CAROLINA COAST ALLOWING A COLD FRONT TO PUSH ACROSS THE AREA LATE
THURSDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FOR 930 AM UPDATE...HAVE MADE A SMALL ADJUSTMENT TO SKY GRIDS TO
ALLOW FOR A LITTLE CU TO DEVELOP. MODELS DIFFER ON WHERE THEY THINK
BETTER 850 MB MOISTURE WILL BE THIS AFTERNOON. ADDED CONVERGENCE
FROM LAKE BREEZE SHOULD AID CU DEVELOPMENT IN THE EASTERN PART OF
THE SNOWBELT. HRRR LATEST RUN NOW DEVELOPS A FEW LIGHT CELLS IN THE
AREA OF WHERE THE LAKEBREEZE CONVERGENCE OCCURS WHILE THE RUN FROM
THE PREVIOUS HOUR HAD SOME ISOLATED LIGHT CELLS SPREAD IN THE SOUTH
AND SE PART OF THE AREA. THINK CAP AT MID LEVELS WILL KEEP ANY
PRECIP FROM DEVELOPING SO WILL KEEP POP BELOW 10%.
TEMPS AND DEWPOINTS SEEM IN LINE SO HEAT INDEX SHOULD STAY JUST
UNDER THRESHOLD NEEDED FOR HEAT ADVISORY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
MODELS IN GOOD AGREEMENT MOVING COLD FRONT INTO NW OH THURSDAY
AFTERNOON AND PUSHING SOUTH OF THE AREA THURSDAY NIGHT. BEST CHANCE
FOR PRECIP LATE AFTERNOON INTO THE EVENING HOURS. SPC HAS AREA IN A
SEE TEXT. CAPES APPROACH 1500 J/KG...BUT VERY LITTLE SHEAR AND
LIMITED MOISTURE.
MUCH COOLER AND DRIER MUCH MORE SEASONAL CONDITIONS RETURN FOR
FRIDAY AND SATURDAY.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
OVERALL THE MODELS ARE FAIRLY SIMILAR BUT SOME DIFFERENCES DO CROP
UP LATE IN THE PERIOD. A WEAK COLD FRONT WILL MOVE ACROSS THE
REGION LATE SUNDAY INTO SUNDAY NIGHT. WILL NEED A MENTION OF PRECIP
WITH THIS FEATURE. HIGH PRESSURE WILL BEGIN TO BUILD OVER THE
REGION FROM NORTHWEST ON MONDAY. 850 MB TEMPS WILL DIP TO THE UPPER
SINGLE DIGITS SO HIGH TEMPS WILL BE A LITTLE BELOW NORMAL BOTH
MONDAY AND TUESDAY. THE MODELS TRACK AN AREA OF LOW PRESSURE UP THE
EAST COAST EARLY NEXT WEEK. THE ECMWF IS A LITTLE FURTHER WEST THAN
THE GFS. AS A RESULT THE ECMWF BRINGS PRECIP INTO THE EASTERN END
OF THE FORECAST AREA. THE GFS KEEPS THE AREA MAINLY DRY. GIVEN THE
FACT THAT PRECIP IS ALREADY IN THE FORECAST WILL CONTINUE WITH A
SMALL MENTION TUESDAY ACROSS FAR NE OH AND NW PA.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
QUIET WEATHER WILL CONTINUE DURING THE PERIOD WITH HIGH PRESSURE
OVER THE AREA. EXPECTING VFR WEATHER THE ENTIRE PERIOD. SOME FAIR
WEATHER CU LIKELY BY MIDDAY AS A VERY WARM AND UNSTABLE AIRMASS
REMAINS OVER THE AREA. LIGHT S TO SW FLOW WILL INCREASE AND BECOME
GUSTY THIS MORNING.
.OUTLOOK...NON VFR POSSIBLE IN SCATTERED THUNDERSTORMS THURSDAY
AFTERNOON AND EVENING.
&&
.MARINE...
QUIET WEATHER WILL CONTINUE ON THE LAKE THE NEXT COUPLE OF DAYS. S
TO SW FLOW GENERALLY IN THE 5 TO 15 KNOT RANGE WILL CONTINUE TILL A
COLD FRONT CROSSES LAKE ERIE SOMETIME LATE THURSDAY. ONSHORE FLOW
IS LIKELY IN THE NEARSHORE WATERS DURING THE AFTERNOON. THE FLOW
WILL BECOME W TO NW BEHIND THE FRONT WITH SPEEDS INCREASING TO
AROUND 15 KNOTS. MAY COME CLOSE TO NEEDING A SMALL CRAFT ADVISORY.
NW TO N FLOW AT UNDER 15 KNOTS CAN BE EXPECTED FROM FRIDAY INTO LATE
SATURDAY. HIGH PRESSURE WILL MOVE OVERHEAD SUNDAY WITH MAINLY LIGHT
AND VARIABLE FLOW. STRONG TO POSSIBLY SEVERE STORMS COULD OCCUR
LATE THURSDAY ALONG AND AHEAD OF THE COLD FRONT.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...DJB
NEAR TERM...DJB/ADAMS
SHORT TERM...DJB
LONG TERM...KUBINA
AVIATION...KUBINA
MARINE...KUBINA
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1049 AM EDT WED JUN 20 2012
.SYNOPSIS...
A RIDGE OF SURFACE HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH
THURSDAY. A WEAKENING COLD FRONT WILL THEN APPROACH FROM THE
NORTHWEST FRIDAY AND MOVE INTO THE AREA SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1040 AM...CURRENT FORECAST LOOKS RIGHT ON TRACK. FORECAST
SOUNDINGS SHOW WARM MID LEVELS WHICH RESULTS IN MEAGER LAPSE RATES.
RAP SOUNDINGS INDICATE THAT PIEDMONT AREAS SHOULD REMAINED
CAPPED...BUT MOUNTAIN LOCATIONS SHOULD BREAK THE CAP WITH HEATING
WITH CAPES IN THE 500-1000J RANGE. GFS AND NAM LOOK OVERDONE ON THE
CONVECTIVE COVERAGE THIS AFTERNOON. MESOMODELS LOOK MORE REASONABLE
WITH JUST WIDELY SCATTERED/SCATTERED CONVECTION. HOWEVER, WILL
DISREGARD THE ISOLD CONVECTION OF HRRR OVER THE PIEDMONT. THE UPSHOT
IS THAT WE WILL STAY THE COURSE WITH WIDELY SCATTERED TYPE POPS
CONFINED TO THE MOUNTAINS FOR THIS AFTERNOON.
PREVIOUS DISCUSSION...
FOR TODAY...THE CENTER OF THE LARGE UPPER RIDGE WILL SLIDE JUST TO
OUR NORTH AND THEN BEGIN TO DAMPEN AS A NORTHERN STREAM UPPER TROF
APPROACHES THE GREAT LAKES EARLY THURS. AT THE SFC...HIGH PRESSURE
WILL PERSIST THRU THE PERIOD BUT SLIDE A BIT FARTHER EAST CAUSING
OUR LOW LVL WINDS TO BECOME MORE SELY THIS AFTERNOON/EVENING.
OTHERWISE...THE SENSIBLE FCST WILL BE VERY SIMILAR TO THE PAST FEW
DAYS WITH A SLIGHT CHANCE POP OVER THE NC MTS FOR SCT TO ISO TSRA
AND A SOLID CHANCE ALONG PORTIONS OF THE TN BORDER DURING PEAK
HEATING. THE REST OF THE CWFA SHOULD REMAIN DRY WITH HIGH TEMPS
AROUND 90 DEGREES FOR THE LOWER ELEVATIONS AND LOW TO MID 80S FOR
THE HIGHER ELEVATIONS. AN AIR QUALITY ALERT IS IN AFFECT FROM 6AM
UNTIL 9PM TODAY FOR ELEVATED AMOUNTS OF GROUND LVL OZONE OVER THE
CLT AND HKY REGIONS.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 AM WEDNESDAY...AS H5 SHORTWAVE MOVES OFFSHORE THU A
SHORTWAVE APPROACHES THE S APPALACHIANS FROM THE NW. BEST FORCING
STAYS WELL N OF THE AREA AND MID LVL RIDGE REMAINS OVER THE CWA.
MODEL SOUNDINGS REMAIN UNIMPRESSIVE...ESP ACROSS THE PIEDMONT...SO
LIMITED SCT CONVECTION TO THE N MTNS WITH ISOLD REST OF MTN RIDGES
AND PEAKS LATE THU AFTN INTO EARLY EVE. A WEAK UPPER WAVE AND ASSOC
COLD FRONT APPROACH THE AREA FROM THE NW FRI. THE GFS SHOWS THE MOST
RESPONSE WITH THE NAM AND ECMWF MORE RESERVED. BASED ON RECENT GFS
PESSIMISM USED A MODEL BLEND...LEANING MORE TOWARD THE NAM/ECMWF.
FCST SOUNDINGS STILL SHOW ENOUGH CAPE AND SHEAR FOR SOLID CHC POPS
ACROSS THE MTNS FRI AFTN...TAPERING TO LOW CHC ACROSS THE FOOTHILLS
AND SLIGHT CHC OVER THE SE CWA. TEMPS WILL BE ABOUT 5 DEG ABOVE AVG
THRU THE PD.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 310 AM WEDNESDAY...LATEST MODEL RUNS KEEP THE UPPER TROF OVER
THE E US THRU THE MIDDLE OF NEXT WEEK. MOISTURE ASSOC WITH
DISTURBANCE(S)IN THE GULF IS EXPECTED TO STAY S AND E OF THE CWA...
WHILE A WEAK SFC BOUNDARY MEANDERS OVER THE AREA THRU THE WEEKEND.
GFS AND ECMWF SHOW WEAK UPPER LVL DIVERGENCE OVER THE REGION SAT-SUN
BUT MOISTURE IS LIMITED. BASED ON THIS KEPT SLIGHT CHC POPS OVER THE
MTNS SAT AND ACROSS THE CWA SUN AS UPPER FORCING IMPROVES SLIGHTLY.
MODELS CONTINUE TO SHOW WEAK SFC BOUNDARY MOVG SE OF THE CWA MON-TUE
WITH LLVL CONVERGENCE AND INSTABILITY SETTING UP ALONG THE COAST...
WHILE THE W CAROLINAS AND NE GA STAY RELATIVELY DRY. TEMPS REMAIN
ABOVE AVG THRU THE FCST PD.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT AND ELSEWHERE...VFR CONDITIONS EXPECTED THRU THE PERIOD WITH
THE EXCEPTION OF LIFR STRATUS FOG AT KAVL UNTIL ABOUT 14Z.
OTHERWISE...CONDITIONS TODAY WILL BE SIMILAR TO YESTERDAY EXCEPT
WINDS WILL LIKELY TAKE ON MORE OF A SELY COMPONENT THIS
AFTERNOON...AS OPPOSED TO SWLY. WINDS SHOULD BECOME CALM AGAIN THIS
EVENING INTO THE OVERNIGHT. I DONT EXPECT ANY SHOWERS OR TS OVER
MOST OF THE FCST AREA WITH ONLY A SLIGHT CHANCE FOR SOME SHOWERS AND
MAYBE A TS OR 2 DEVELOPING OVER THE NC MOUNTAINS AFTER 17Z OR SO.
OUTLOOK...GENERALLY DRY/VFR CONDITIONS ARE EXPECTED EAST OF MTNS
THRU THURSDAY. EXPECT ISOLATED TO SCATTERED AFTERNOON TSTMS OVER THE
MTS...WITH VALLEY FOG POSSIBLE DURING THE MORNING. A WEAK COLD
FRONT APPROACHING THE AREA WILL INCREASE CHANCES FOR CONVECTION
FRIDAY AND SATURDAY...WITH DRYING POSSIBLE BY SUNDAY.
AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...
WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...RB
NEAR TERM...LG
SHORT TERM...RB
LONG TERM...RB
AVIATION...JPT
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1043 AM CDT WED JUN 20 2012
.UPDATE...LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LOW
PRESSURE AND ASSOCIATED COLD FRONT NOW MOVING INTO NORTHWEST
WISCONSIN THIS MORNING. CONVECTION AHEAD OF THE FRONT AND IN THE
RIGHT REAR QUAD OF JET STREAK WILL STAY NORTHWEST OF THE FORECAST
ARE THIS MORNING. BUT DO LOOK FOR THUNDERSTORMS TO REDEVELOP ALONG
THE FRONT LATER THIS AFTERNOON. THE SPC WRF AND OTHER GUIDANCE
POINT TOWARDS CONVECTION MOVING INTO N-C WISCONSIN AFTER 21Z AND
INTO NORTHEAST WISCONSIN AFTER 03Z. PROGGED NAM SOUNDINGS SHOW
1500-2000 J/KG OF ML CAPE AND 30-35 KTS OF EFFECTIVE SHEAR AHEAD
OF THE BOUNDARY THIS AFTERNOON. THE MAIN THREAT WILL CONTINUE TO
BE STRONG GUSTY WINDS BUT DO NOT THINK CAN RULE OUT LARGE HAIL
DURING THE PEAK HEATING PERIOD UNTIL INSTABILITY RAPIDLY
DIMINISHES IN THE EVENING. NORTHEAST WISCONSIN SHOULD BE
RELATIVELY SAFER FROM SEVERE WEATHER AS THEY ARRIVE LATE IN THE EVENING.
MPC
&&
.PREV DISCUSSION...ISSUED AT 645 AM CDT WED JUN 20 2012...
SHORT TERM...TODAY THROUGH THURSDAY...MAIN FCST CONCERNS INCLUDE
PCPN TIMING...AND THE THREAT OF SVR TSTMS AND HEAVY RAINFALL THIS
AFTERNOON AND EVENING.
MSAS ANALYSIS SHOWED A SFC LOW IN SW MN...WITH A COLD FRONT EXTENDING
SWWD INTO THE CENTRAL PLAINS...AND A WARM FRONT EXTENDING NEWD
INTO FAR NW WI AND THE UPPER PENINSULA. A LARGE AREA OF SHRA/TSRA
WAS ONGOING NW OF THE COLD FRONT AND NORTH OF THE WARM FRONT...
WITH TRAINING LEADING TO HEAVY RAINFALL AND SOME FLOODING FROM
EASTERN SD INTO THE MN ARROWHEAD. CLEAR TO PARTLY CLOUDY SKIES
COVERED GRB CWA...BUT DEVELOPING CONVECTION WAS EDGING TOWARD OUR
FAR NW COUNTIES EARLY THIS MORNING.
ALTHOUGH CURRENT CONVECTION MAY BRUSH PARTS OF NC WI THIS MORNING...
MODELS CONTINUE TO SUGGEST THAT THE MAIN BRUNT OF THE PCPN WILL
OCCUR ALONG AND BEHIND THE COLD FRONT AS IT MOVES INTO GRB CWA
LATER THIS AFTERNOON AND EVENING. MODIFIED FCST SOUNDINGS WOULD
INDICATE THAT SFC BASED CONVECTION COULD DEVELOP ALONG THE COLD
FRONT OVER PARTS OF NC/C WI LATER THIS AFTERNOON...AS MID-LEVEL
CAA ERODES THE CAP AND SBCAPE INCREASES TO AROUND 2000 J/KG. STRONG
UNIDIRECTIONAL SW WINDS AND WINDEX VALUES AROUND 55 KTS SUGGEST
THAT DAMAGING WINDS ARE A GOOD BET IF SFC BASED CONVECTION CAN
DEVELOP. NOT QUITE CONFIDENT ENOUGH TO EXPLICITLY MENTION SEVERE
WORDING IN THE GRIDS/FCST...BUT WILL CERTAINLY HIGHLIGHT THE
POTENTIAL IN THE HWO. CONFIDENCE IS HIGHER IN THE THREAT OF HVY
RAINFALL...AS PW`S INCREASE TO NEAR 2 INCHES AND H8 DEW POINTS
RISE TO AROUND 16 C IN THE VCNTY OF THE COLD FRONT. THE COMBINATION
OF LLVL CONVERGENCE ALONG THE BOUNDAY AND INCREASING UPPER LEVEL
DIVG IN THE RRQ OF A STG UPPER LEVEL JET ARE ALSO SUPPORTIVE OF
A HEAVY RAINFALL THREAT...SO WILL MENTION IN THE FCST. WILL HAVE
LIKELY POPS IN THE FAR NW COUNTIES THIS AFTERNOON...THEN SPREAD
THEM ACROSS THE REST OF THE CWA TONIGHT. A VERY WARM START TO THE
DAY COMBINED WITH MIXING THROUGH 825-800 MB SUPPORTS HIGHS IN THE
80S TO LOWER 90S TODAY. THE DEEP MIXING WILL ALSO LEAD TO WINDS
GUSTING OVER 30 MPH AT TIMES THIS AFTERNOON AND EARLY EVG.
THE FRONT WILL SHIFT EAST OF THE RGN BY THURSDAY MORNING...WITH
COOLER AND DRIER AIR ARRIVING. WILL CONTINUE WITH THE PREVIOUS
DRY FCST...AND MAX TEMPS THAT ARE 10-15 DEGREES COOLER THAN
TODAY.
LONG TERM...THURSDAY NIGHT THROUGH TUESDAY.
MODELS HAD A MID LEVEL TROUGH PASSING EAST OF WISCONSIN AT THE
START OF THE FORECAST PERIOD. A 500MB LOW WAS THEN FORECAST TO
DEVELOP EAST OF THE STATE AS A CENTRAL CONUS RIDGE BUILDS. THIS
WILL KEEP THE FORECAST AREA IN NORTHWEST FLOW ALOFT THROUGH EARLY
NEXT WEEK. THIS SHOULD BRING A PERIOD OF MOSTLY DRY WEATHER
WITH TEMPERATURES NEAR NORMAL FOR THIS TIME OF YEAR.
HAVE SLIGHT CHANCE POPS FOR THURSDAY NIGHT INTO FRIDAY AS 00Z
GFS/00Z NAM/12Z ECMWF ALL HAD SOME QPF DURING ONE OR BOTH OF THOSE
PERIODS AND CYCLONIC FLOW PERSISTS AT BOTH THE SURFACE AND ALOFT.
SHORT WAVE ENERGY COMBINED WITH THE RIGHT ENTRANCE REGION OF AN
UPPER LEVEL JET AND AN APPROACHING SURFACE SYSTEM WILL BRING A
CHANCE OF SHOWERS AND THUNDERSTORMS TO THE AREA FRIDAY NIGHT
THROUGH SATURDAY NIGHT IN THE WEST AND SATURDAY THROUGH SUNDAY IN
THE EAST. HIGH PRESSURE THEN MOVES INTO THE REGION AS THE UPPER
RIDGE CONTINUES TO BUILD TO THE WEST. AS A RESULT...HAVE GONE WITH
A DRY FORECAST FOR THE REST OF THE PERIOD.
&&
.AVIATION...WILL CONTINUE LLWS FOR A COUPLE HOURS THIS MORNING...
BUT DAYTIME MIXING WILL REDUCE THE THREAT AND PROMOTE GUSTY WINDS
AT THE SURFACE FOR THE REST OF THE DAY. COULD SEE GUSTS AS HIGH AS
30 KTS FROM MID-AFTERNOON THROUGH EARLY EVENING. SHRA/TSRA WILL
ARRIVE IN NC/C WI DURING THE LATE AFTERNOON/EARLY EVG...AND SPREAD
EAST TONIGHT. SVR TSTMS WITH DAMAGING WINDS AND HEAVY RAINFALL
ARE POSSIBLE...ESPECIALLY AT THE WESTERN TAF SITES. HAVE PUT A
FOUR HOUR TEMPO GROUP FOR TSTMS AT EACH TAF SITE...WITH AN ESTIMATE
OF THE MOSTLY LIKELY TIME PERIOD FOR DEVELOPMENT. LLWS MAY REDEVELOP
THIS EVG...AND LAST UNTIL THE COLD FRONT PASSES THROUGH. SOME LOW
CLOUDS...WITH IFR/MVFR CIGS...ARE POSSIBLE IN THE WAKE OF THE
FRONT LATER TONIGHT.
KIECKBUSCH
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1114 AM MDT WED JUN 20 2012
.UPDATE...
&&
.SHORT TERM...HIGH STRATUS DECK STARTING TO MIX OUT AND WITH MUCH
DRIER AIR ABOVE THE FRONTAL INVERSION...SKIES SHOULD CLEAR OUT
PRETTY WELL THIS AFTERNOON. WILL HOLD ON TO THE SLIGHT CHANCE OF
STORMS AROUND PARK COUNTY THIS EVENING...BUT IT IS LOOKING LIKE
THE MOISTURE MAY NOT BE DEEP ENOUGH TO HANG ON IN THAT AREA. NO
CHANGES NEEDED AT THIS TIME.
&&
.AVIATION...EXPECTING THE CEILING IN THE DENVER AREA TO BREAK UP
IN THE NEXT HOUR OR TWO. NO CHANGES NEEDED.
&&
.FIRE WEATHER...COOL MOIST LAYER HAS PUSHED ABOUT TWO THIRDS OF
THE WAY UP THE EAST SLOPE OF THE FRONT RANGE...BUT LOOKS TO BE
MIXING WITH THE DRIER AIR AS THE WINDS PUSH FURTHER WEST. WEST
SIDE OF THE HIGH PARK FIRE AND AND THE SPRINGER FIRE MAY STILL BE
IN RELATIVELY DRY AIR AND COULD HAVE SOME SOUTH TO SOUTHWEST WINDS
MIXING DOWN LATE IN THE DAY...WHILE LOWER ELEVATIONS SHOULD STAY
COOLER WITH HIGHER HUMIDITIES. HOTTER/BREEZIER/VERY DRY ON FRIDAY
AND SATURDAY...EVALUATING FOR POSSIBLE FIRE WEATHER WATCH.
&&
.PREV DISCUSSION... /ISSUED 407 AM MDT WED JUN 20 2012/
SHORT TERM...COLD FRONT HAS PUSHED SOUTH ACROSS THE PLAINS WITH
LOW LEVEL MOISTURE INCREASING AND DEWPOINTS RISING INTO THE 40S
AND LOWER 50S. LATEST MSAS ANALYSIS SHOWS BEST PRESSURE RISE
CENTER PUSHING THROUGH WESTERN NEBRASKA...HELPING LOW LEVEL WINDS
TURN A BIT NORTHEASTERLY ACROSS THE PLAINS. LOOKS LIKE SHORT RANGE
MESOSCALE MODELS INCLUDING THE HRRR HAVE THE BEST HANDLE ON THIS
LOW LEVEL MOISTURE AND COOLER AIR AT THIS TIME...ALTHOUGH EVEN THE
NAM AND GFS SUGGEST THE SAME SCENARIO JUST WITHOUT THE HIGHER
RESOLUTION. NONETHELESS...THERE WILL BE A VERY SHARP LINE OF
SINGLE DIGIT DEWPOINTS OVER THE HIGH COUNTRY BATTLING UPPER 30S
AND 40S DEWPOINTS BACKING INTO THE FOOTHILLS AND PORTIONS OF
SOUTH PARK DURING THE DAY. THE INCREASE IN LOW LEVEL MOISTURE AND
UPSLOPE FLOW WILL ALSO AID STRATUS FORMATION ACROSS THE PLAINS AND
PERHAPS LOWER FOOTHILLS EARLY THIS MORNING.
TEMPERATURES WILL BE A GOOD 20 DEGREES COOLER ACROSS THE PLAINS
AND FOOTHILLS TODAY WITH THE RATHER STRONG AND DEEP COLD
ADVECTION. EVEN IN THE MOUNTAINS...GRIDDED TEMP FIELDS SHOW ABOUT
10-16 DEGREES COOLING. AIRMASS WILL BE TOO COOL IN THE LOW LEVEL
TO SUPPORT ANY CONVECTION...ALTHOUGH CANT TOTALLY RULE OUT A
SHOWER OR STORM IN THE PARK COUNTY AREA BY THIS EVENING WITH
ENOUGH MOISTURE POOLING THERE AND SLIGHTLY WEAKER CAP. PARTIAL
CLEARING LATER TONIGHT SHOULD ALLOW FOR A PLEASANTLY COOL NIGHT
FOR A CHANGE.
LONG TERM...COOL TEMPERATURES...OR AT LEAST TEMPERATURES AROUND
SEASONAL NORMALS WILL HANG ON FOR ONE MORE DAY THURSDAY AS
SOUTHEASTERLY LOW LEVEL FLOW CONTINUES ACROSS EASTERN COLORADO.
MODERATE DEW POINTS WILL ALSO REMAIN ON THE PLAINS...HELPING TO
KEEP TEMPERATURES FROM WARMING TOO RAPIDLY. EVEN THOUGH SOME LOW
LEVEL MOISTURE WILL BE IN PLACE OVER THE REGION...STRONG
SUBSIDENCE AT MID LEVELS ASSOCIATED WITH RISING HEIGHTS OVER THE
STATE WILL KEEP MOST CONVECTION CAPPED. MODELS ARE VERY SKIMPY IN
PRODUCING ANY QPF THURSDAY AFTERNOON AND EVENING. AFTER
THURSDAY...THE UPPER RIDGE STRENGTHENS OVER THE SOUTH CENTRAL
UNITED STATES WITH COLORADO UNDER WARM SOUTHWESTERLY FLOW ALOFT.
WARM TEMPERATURES OUT OF THE DESERT SOUTHWEST WILL ONCE AGAIN
ADVECT ACROSS OUR REGION. MOS TEMPERATURE GUIDANCE POPS
TEMPERATURES INTO THE MID AND UPPER 90S FOR THE FRIDAY THROUGH
THE WEEKEND AND INTO EARLY NEXT WEEK. OPPORTUNITIES FOR ANY
PRECIPITATION WILL BE SPARSE AS THE STATE REMAINS CUT OFF FROM ANY
MOISTURE SOURCES. THE GFS AND ECMWF HINT AT A PLUME OF MOISTURE
ARCING ACROSS ARIZONA INTO UTAH NEXT TUESDAY...BUT THIS WOULD BE
TOO FAR WEST TO BRING ANY BENEFICIAL RAIN INTO COLORADO. WARM
TEMPERATURES AND LOW HUMIDITIES WILL CONTINUE TO PRESENT PROBLEMS
FOR FIRE MANAGERS WITH NO REAL RELIEF IN SIGHT.
AVIATION...TEMPERATURE/DEWPOINT SPREADS WILL NARROW EARLY THIS
MORNING AND WITH CONTINUED UPSLOPE FLOW EXPECT A FAIRLY LOW
STRATUS DECK TO DEVELOP IN THE 11Z-15Z TIME FRAME WITH IFR
CONDITIONS POSSIBLE. CEILINGS WILL LIKELY GRADUALLY LIFT BUT
INSTRUMENT LANDINGS MAY STILL BE REQUIRED THROUGH 18Z WITH
CONTINUED UPSLOPE FLOW SLOWING STRATUS DISSIPATION. BUT OVERALL
EXPECT A GRADUAL LIFT/BREAKUP FROM 16Z-19Z WITH DAYTIME HEATING.
THERE ARE INDICATIONS OF A 6000-7000 FT AGL CEILING REDEVELOPING
AROUND 00Z-02Z AS UPSLOPE MOISTURE GETS TRAPPED UNDER A STRONG
CAPPING INVERSION.
FIRE WEATHER...THERE WILL BE A VERY SHARP DIVIDE IN A MOIST
AIRMASS BACKING INTO THE FOOTHILLS AND PARK COUNTY TODAY VERSUS
MUCH DRIER AIR REMAINING OVER MUCH OF GRAND AND SUMMIT COUNTIES
THROUGH THE DAY. AT THIS TIME...WE DO EXPECT A MORE EAST/SOUTHEAST
MOIST FLOW TO DEVELOP IN BOTH THE HIGH PARK AND SPRINGER FIRE
AREAS THIS MORNING PER THE HRRR...ALTHOUGH THE SPRINGER FIRE COULD
VERY WELL WOBBLE BETWEEN THE TWO AIRMASSES BEFORE THE DEEPER MOIST
AIRMASS FINALLY WINS OUT LATER THIS AFTERNOON. WE WILL BE CLOSE TO
RED FLAG CONDITIONS IN PORTIONS OF SUMMIT...GRAND...AND WESTERN
PARK COUNTIES WHERE THE VERY DRY ARIMASS AND LOW HUMIDITY
READINGS PREVAIL. HOWEVER...WINDS SHOULD BE SLIGHTLY WEAKER THAN
THE LAST COUPLE DAYS.
HYDROLOGY...NO CONCERNS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BARJENBRUCH
LONG TERM....DANKERS
AVIATION/UPDATE...GIMMESTAD
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
327 PM CDT WED JUN 20 2012
.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 323 PM CDT WED JUN 20 2012
A STRONG UPPER LEVEL SHORTWAVE TROUGH WILL MOVE FROM THE NORTHERN
PLAINS THIS AFTERNOON AND INTO THE UPPER MIDWEST BY TOMORROW
MORNING. AN ASSOCIATED COLD FRONT EXTENDS FROM DIGHTON TO JUST WEST
OF DODGE CITY TO NEAR LIBERAL WILL CONTINUE TO WORK TO THE EAST INTO
TONIGHT. THE FRONT SHOULD BE NEAR MEDICINE LODGE BY 7 PM THIS
EVENING THEN EXIT OUR FA INTO OKLAHOMA AND WEST TEXAS TONIGHT.
THUNDERSTORMS WILL CONTINUE TO UNZIP ALONG THE COLD FRONT MAINLY
AFTER 4 PM AND COULD BE NEAR OR JUST EAST OF A HAYS TO DODGE CITY TO
MEADE LINE. SOME STORMS COULD BE SEVERE WITH STRONG OUTFLOW WIND
GUSTS AND HAIL UP TO QUARTER SIZE. UPPER TO MID LEVEL WINDS REMAIN
WEAK SO ANY STORMS THAT FORM SHOULD COLLAPSE FAIRLY QUICKLY WITH NEW
OUTFLOW KICKING OFF MORE STORMS. WILL MAINTAIN HIGHEST POPS FROM 20
TO 50 PERCENT THIS EVENING MAINLY EAST OF A LACROSSE TO DODGE CITY
TO MEADE LINE, THEN GRADUALLY DECREASE POPS INTO 6 AM THURSDAY. AS
THE UPPER LEVEL WAVE CONTINUES TO MOVE EAST ON THURSDAY, SURFACE
HIGH PRESSURE WILL BUILD INTO THE CENTRAL PLAINS WITH THE RAINFALL
AREAS INTO OKLAHOMA AND WEST TEXAS. NORTH WINDS OF 20 TO 30 MPH
BEHIND THE COLD FRONT LATER THIS AFTERNOON INTO EARLY EVENING WILL
GRADUALLY BECOME NORTHEASTERLY AND DECREASE TO AROUND 10 MPH AFTER
MIDNIGHT. WINDS THEN BECOME EAST TO SOUTHEAST ON THURSDAY AROUND 10
TO 20 MPH.
OVERNIGHT LOWS WILL RANGE FROM THE UPPER 50S NORTH AND WEST FROM
ELKHART TO HAYS AND FROM 60 TO 65 SOUTH. HIGH TEMPERATURES TOMORROW
WILL RANGE FROM THE MID 80S NORTH TO THE LOWER 80S SOUTH. COOLER
TEMPS ARE EXPECTED SOUTH OF DODGE CITY WITH MORE CLOUDS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 319 PM CDT WED JUN 20 2012
A 590+ DECAMETER 500MB HIGH IS ANTICIPATED TO BUILD ABOVE THE
CENTRAL HIGH PLAINS FRIDAY THEN ANCHOR ITSELF AND STRENGTHEN
THROUGHOUT THE MIDDLE OF NEXT WEEK. THIS WILL ALLOW THE EML TO
FILTER BACK INTO THE HIGH PLAINS IN THE MID LEVELS OF THE
ATMOSPHERE. WITH THE LACK OF MOISTURE AND VERY WARM TEMPERATURES IN
THE MID LEVELS, MOSTLY CLEAR SKIES AND DRY CONDITIONS ARE EXPECTED
TO PREVAIL ACROSS WESTERN KANSAS THROUGH EARLY NEXT WEEK. A
PERSISTENT UPPER LEVEL LONG WAVE TROUGH ACROSS THE WESTERN CONUS
WILL HELP REDEVELOP SURFACE LEE TROUGHING ACROSS EASTERN COLORADO ON
FRIDAY AND CONTINUE THROUGH THE EXTENDED PERIOD. EASTERLY WINDS
THURSDAY NIGHT WILL SHIFT BACK TO A SOUTHERLY DIRECTION FRIDAY
THROUGH TUESDAY BECOMING BREEZY IN THE AFTERNOONS WHEN THE
ATMOSPHERE MIXES AND THE PRESSURE GRADIENT TIGHTENS. HIGHS FRIDAY
ARE FORECASTED TO REACH TO AROUND 90 DEGREES WITH HIGHS RANGING FROM
THE UPPER 90S TO 105 SATURDAY THROUGH TUESDAY. THE WARMEST DAYS ARE
ANTICIPATED TO BE ON SATURDAY AND SUNDAY. LOWS FRIDAY MORNING ARE
ANTICIPATED TO DIP INTO THE LOWER 60S WITH LOWS RANGING FROM AROUND
70 DEGREES TO MID 70S SATURDAY MORNING THROUGH TUESDAY MORNING. WITH
VERY WARM SURFACE TEMPERATURES AND SURFACE DEWPOINTS REACHING INTO
THE 60S THERE COULD BE A FEW THUNDERSTORMS THAT FORM ACROSS THE
KS/CO BORDER IN THE AFTERNOON. HOWEVER, IF THESE STORMS DO FORM THEY
WILL MOST LIKELY BE SHORT LIVED AND ISOLATED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1221 PM CDT WED JUN 20 2012
A COLD FRONT STRETCHES FROM HUGOTON TO JUST WEST OF KGCK AND SCOTT
CITY WITH A PRE-FRONTAL TROUGH WIND SHIFT EAST OF THAT LINE NEAR
LIBERAL TO KGCK TO DIGHTON. EXPECT WINDS TO SHIFT NORTH AND
INCREASE TO 20 TO 25 KTS AT KDDC AND KHYS BETWEEN 19 TO 21Z WITH
THE COLD FRONT. THE LATEST RAP FORECAST SHOWS A LINE OF
THUNDERSTORMS BEGINNING AROUND 21Z FROM KHYS TO KDDC AND KLBL.
OTHER SHORT TERM MODELS KEEP THE LINE OF STORMS JUST EAST OF THE
TAF SITES. FOR NOW WITH THE SOUNDING SHOWING A STRONG CAPPING
INVERSION WILL CONTINUE TO KEEP THUNDER OUT OF THE TAFS AND JUST
TO THE EAST. CIGS COULD LOWER BRIEFLY TO MFVR CONDITIONS AROUND
03-05Z OTHERWISE VFR CONDITIONS ARE EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 61 84 62 91 / 10 10 10 10
GCK 59 84 60 92 / 10 10 10 10
EHA 58 81 64 95 / 30 10 10 10
LBL 61 82 63 94 / 30 10 10 10
HYS 58 85 59 91 / 20 0 10 10
P28 64 84 63 90 / 60 20 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...KRUSE
LONG TERM...HOVORKA_42
AVIATION...KRUSE
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
320 PM CDT WED JUN 20 2012
...UPDATED LONG TERM SECTION...
.SYNOPSIS...
ISSUED AT 321 AM CDT WED JUN 20 2012
THE 20.00Z UPPER AIR CHARTS REVEALED A FAIRLY SIGNIFICANT STORM
SYSTEM CENTERED OVER THE NORTHERN ROCKIES. THERE WERE TWO DISTINCT
MID LEVEL VORTICITY CENTERS...ONE NORTH OF GLASGOW, MT JUST NORTH OF
THE CANADA BORDER...AND ANOTHER ONE FARTHER TO THE SOUTHWEST OVER
EASTERN IDAHO ENTERING WESTERN WYOMING. AN OCCLUDED LOW AT 850MB
WAS ANALYZED OVER SOUTHERN SASKATCHEWAN TIED TO THE FIRST MINOR WAVE
WITH A NEW LOW DEVELOPING AT THE OCCLUSION POINT OVER NORTHEASTERN
SOUTH DAKOTA. A COLD FRONT EXTENDED SOUTHWEST OF THE NEW LOW INTO
THE NORTHERN NEBRASKA PANHANDLE. THUNDERSTORMS ERUPTED BOTH IN THE
WARM FRONTAL ZONE NORTHEAST OF THE SURFACE LOW ACROSS NORTHERN
MINNESOTA...AND ALONG THE COLD FRONT IN THE NORTHERN NEBRASKA
PANHANDLE. THE MOST ROBUST CONVECTION AS OF 0745 UTC WAS FOUND OVER
THE WESTERN NEBRASKA SANDHILLS AROUND THE HYANNIS AREA NORTHWEST OF
NORTH PLATTE. INFRARED SATELLITE (USING A SUPER-ENHANCED COLOR CURVE)
SHOWED THE COLD FRONT BEGINNING TO SURGE SOUTHWARD THROUGH
NORTHEASTERN COLORADO AS OF 0745 UTC PRIMARILY DUE TO COLD POOL
GENERATION FROM THE NEBRASKA PANHANDLE CONVECTION.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 321 AM CDT WED JUN 20 2012
THE TIMING OF THE FRONT IS THE BIG QUESTION FOR LATER ON
TODAY...SEEING AS IT WILL PLAY A HUGE ROLE AS TO WHERE THUNDERSTORMS
WILL FIRST DEVELOP. IT SEEMS PRETTY CLEAR BASED ON ALL THE SHORT
TERM HIGH RESOLUTION CONVECTION ALLOWING MODELS (AND THE LOWER
RESOLUTION MODELS USING A PARAMETRIZATION SCHEME) THAT THUNDERSTORMS
WILL DEVELOP BY LATE THIS AFTERNOON ALONG THE FRONT AS FAR SOUTHWEST
AS SOUTHWEST KANSAS AND INTO THE NORTHERN TX-OK PANHANDLE REGION.
THE BEST FORECAST IS THUNDERSTORMS FIRST FORMING JUST SOUTHEAST OF A
HAYS TO DODGE CITY LINE IN THE 20-22Z TIME FRAME. FAIRLY HIGH
SURFACE-BASED CAPE (2400-2800 J/KG) WILL HAVE DEVELOPED BY THEN
ALONG AND AHEAD OF THE COLD FRONT WITH TEMPERATURES WARMING INTO THE
LOWER TO MID 90S AND DEWPOINT TEMPERATURES GENERALLY IN THE LOWER TO
MID 60S. WIND SHEAR WILL BE QUITE LOW THROUGH THE DEPTH OF THE
TROPOSPHERE WITH 0-6KM BULK SHEAR MAGNITUDES 18 TO 25 KNOTS WITHIN
THE HIGHEST CAPE AREA ALONG AND AHEAD OF THE FRONT. THERE WILL BE
ENOUGH SHEAR TO SUPPORT GENERALLY MULTICELL CLUSTERS...BUT SUPERCELL
STRUCTURES ARE UNLIKELY. THE THINKING IS MAX HAIL SIZE OF ONE TO
PERHAPS ONE AND A HALF INCH DIAMETER AND THE TYPICAL DAMAGING WIND
GUSTS TO 65 MPH OR SO IN THIS KIND OF ENVIRONMENT. SLOW MOVEMENT OF
THE STORMS WILL LEAD TO A LOCAL HEAVY RAIN THREAT AS WELL.
WILL BE CARRYING LIKELY POPS AROUND 60 PERCENT FOR ONLY THE COUNTIES
ACROSS SOUTH-CENTRAL KANSAS (COMANCHE, BARBER, PRATT)...WITH POPS
RAPIDLY DECREASING TO THE NORTHWEST TO 20 PERCENT FROM ELKHART TO
JETMORE TO HAYS. ONE OR TWO STRONG/SEVERE CLUSTERS WILL PERSIST
THROUGH THE EVENING AND LATE NIGHT MOST LIKELY ALONG THE
KANSAS-OKLAHOMA BORDER SO WILL KEEP HIGHEST POPS ACROSS THE EXTREME
SOUTH (ALONG THE OKLAHOMA BORDER) THROUGH 06Z WITH POPS DECREASING
TO AROUND 20 PERCENT BY DAYBREAK AS THE MAIN CONVECTIVE ACTIVITY
SHIFTS FURTHER SOUTH INTO THE OKLAHOMA-TEXAS PANHANDLES. SOME
REMNANT POST-FRONTAL SHOWERY TYPE PRECIPITATION COULD LINGER ON
THROUGH DAYBREAK ACROSS SOUTHERN COUNTIES WHERE WEAK MID LEVEL
FRONTOGENESIS MAY CONTINUE...BUT THE BULK OF THE ACTIVITY WILL BE
OFF TO THE SOUTH BY THEN.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 319 PM CDT WED JUN 20 2012
A 590+ DECAMETER 500MB HIGH IS ANTICIPATED TO BUILD ABOVE THE
CENTRAL HIGH PLAINS FRIDAY THEN ANCHOR ITSELF AND STRENGTHEN
THROUGHOUT THE MIDDLE OF NEXT WEEK. THIS WILL ALLOW THE EML TO
FILTER BACK INTO THE HIGH PLAINS IN THE MID LEVELS OF THE
ATMOSPHERE. WITH THE LACK OF MOISTURE AND VERY WARM TEMPERATURES IN
THE MID LEVELS, MOSTLY CLEAR SKIES AND DRY CONDITIONS ARE EXPECTED
TO PREVAIL ACROSS WESTERN KANSAS THROUGH EARLY NEXT WEEK. A
PERSISTENT UPPER LEVEL LONG WAVE TROUGH ACROSS THE WESTERN CONUS
WILL HELP REDEVELOP SURFACE LEE TROUGHING ACROSS EASTERN COLORADO ON
FRIDAY AND CONTINUE THROUGH THE EXTENDED PERIOD. EASTERLY WINDS
THURSDAY NIGHT WILL SHIFT BACK TO A SOUTHERLY DIRECTION FRIDAY
THROUGH TUESDAY BECOMING BREEZY IN THE AFTERNOONS WHEN THE
ATMOSPHERE MIXES AND THE PRESSURE GRADIENT TIGHTENS. HIGHS FRIDAY
ARE FORECASTED TO REACH TO AROUND 90 DEGREES WITH HIGHS RANGING FROM
THE UPPER 90S TO 105 SATURDAY THROUGH TUESDAY. THE WARMEST DAYS ARE
ANTICIPATED TO BE ON SATURDAY AND SUNDAY. LOWS FRIDAY MORNING ARE
ANTICIPATED TO DIP INTO THE LOWER 60S WITH LOWS RANGING FROM AROUND
70 DEGREES TO MID 70S SATURDAY MORNING THROUGH TUESDAY MORNING. WITH
VERY WARM SURFACE TEMPERATURES AND SURFACE DEWPOINTS REACHING INTO
THE 60S THERE COULD BE A FEW THUNDERSTORMS THAT FORM ACROSS THE
KS/CO BORDER IN THE AFTERNOON. HOWEVER, IF THESE STORMS DO FORM THEY
WILL MOST LIKELY BE SHORT LIVED AND ISOLATED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1221 PM CDT WED JUN 20 2012
A COLD FRONT STRETCHES FROM HUGOTON TO JUST WEST OF KGCK AND SCOTT
CITY WITH A PRE-FRONTAL TROUGH WIND SHIFT EAST OF THAT LINE NEAR
LIBERAL TO KGCK TO DIGHTON. EXPECT WINDS TO SHIFT NORTH AND
INCREASE TO 20 TO 25 KTS AT KDDC AND KHYS BETWEEN 19 TO 21Z WITH
THE COLD FRONT. THE LATEST RAP FORECAST SHOWS A LINE OF
THUNDERSTORMS BEGINNING AROUND 21Z FROM KHYS TO KDDC AND KLBL.
OTHER SHORT TERM MODELS KEEP THE LINE OF STORMS JUST EAST OF THE
TAF SITES. FOR NOW WITH THE SOUNDING SHOWING A STRONG CAPPING
INVERSION WILL CONTINUE TO KEEP THUNDER OUT OF THE FORECAST AND
JUST TO THE EAST. CIGS COULD LOWER BRIEFLY TO MFVR CONDITIONS
AROUND 03-05Z OTHERWISE VFR CONDITIONS ARE EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 63 84 61 90 / 20 10 10 10
GCK 62 83 59 90 / 10 10 10 10
EHA 62 81 64 94 / 20 20 10 10
LBL 64 83 62 93 / 30 20 10 10
HYS 61 85 58 91 / 20 10 10 10
P28 69 85 62 90 / 50 20 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...UMSCHEID
SHORT TERM...UMSCHEID
LONG TERM...HOVORKA_42
AVIATION...KRUSE
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1236 PM CDT WED JUN 20 2012
...UPDATED FOR AVIATION...
.SYNOPSIS...
ISSUED AT 321 AM CDT WED JUN 20 2012
THE 20.00Z UPPER AIR CHARTS REVEALED A FAIRLY SIGNIFICANT STORM
SYSTEM CENTERED OVER THE NORTHERN ROCKIES. THERE WERE TWO DISTINCT
MID LEVEL VORTICITY CENTERS...ONE NORTH OF GLASGOW, MT JUST NORTH OF
THE CANADA BORDER...AND ANOTHER ONE FARTHER TO THE SOUTHWEST OVER
EASTERN IDAHO ENTERING WESTERN WYOMING. AN OCCLUDED LOW AT 850MB
WAS ANALYZED OVER SOUTHERN SASKATCHEWAN TIED TO THE FIRST MINOR WAVE
WITH A NEW LOW DEVELOPING AT THE OCCLUSION POINT OVER NORTHEASTERN
SOUTH DAKOTA. A COLD FRONT EXTENDED SOUTHWEST OF THE NEW LOW INTO
THE NORTHERN NEBRASKA PANHANDLE. THUNDERSTORMS ERUPTED BOTH IN THE
WARM FRONTAL ZONE NORTHEAST OF THE SURFACE LOW ACROSS NORTHERN
MINNESOTA...AND ALONG THE COLD FRONT IN THE NORTHERN NEBRASKA
PANHANDLE. THE MOST ROBUST CONVECTION AS OF 0745 UTC WAS FOUND OVER
THE WESTERN NEBRASKA SANDHILLS AROUND THE HYANNIS AREA NORTHWEST OF
NORTH PLATTE. INFRARED SATELLITE (USING A SUPER-ENHANCED COLOR CURVE)
SHOWED THE COLD FRONT BEGINNING TO SURGE SOUTHWARD THROUGH
NORTHEASTERN COLORADO AS OF 0745 UTC PRIMARILY DUE TO COLD POOL
GENERATION FROM THE NEBRASKA PANHANDLE CONVECTION.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 321 AM CDT WED JUN 20 2012
THE TIMING OF THE FRONT IS THE BIG QUESTION FOR LATER ON
TODAY...SEEING AS IT WILL PLAY A HUGE ROLE AS TO WHERE THUNDERSTORMS
WILL FIRST DEVELOP. IT SEEMS PRETTY CLEAR BASED ON ALL THE SHORT
TERM HIGH RESOLUTION CONVECTION ALLOWING MODELS (AND THE LOWER
RESOLUTION MODELS USING A PARAMETRIZATION SCHEME) THAT THUNDERSTORMS
WILL DEVELOP BY LATE THIS AFTERNOON ALONG THE FRONT AS FAR SOUTHWEST
AS SOUTHWEST KANSAS AND INTO THE NORTHERN TX-OK PANHANDLE REGION.
THE BEST FORECAST IS THUNDERSTORMS FIRST FORMING JUST SOUTHEAST OF A
HAYS TO DODGE CITY LINE IN THE 20-22Z TIME FRAME. FAIRLY HIGH
SURFACE-BASED CAPE (2400-2800 J/KG) WILL HAVE DEVELOPED BY THEN
ALONG AND AHEAD OF THE COLD FRONT WITH TEMPERATURES WARMING INTO THE
LOWER TO MID 90S AND DEWPOINT TEMPERATURES GENERALLY IN THE LOWER TO
MID 60S. WIND SHEAR WILL BE QUITE LOW THROUGH THE DEPTH OF THE
TROPOSPHERE WITH 0-6KM BULK SHEAR MAGNITUDES 18 TO 25 KNOTS WITHIN
THE HIGHEST CAPE AREA ALONG AND AHEAD OF THE FRONT. THERE WILL BE
ENOUGH SHEAR TO SUPPORT GENERALLY MULTICELL CLUSTERS...BUT SUPERCELL
STRUCTURES ARE UNLIKELY. THE THINKING IS MAX HAIL SIZE OF ONE TO
PERHAPS ONE AND A HALF INCH DIAMETER AND THE TYPICAL DAMAGING WIND
GUSTS TO 65 MPH OR SO IN THIS KIND OF ENVIRONMENT. SLOW MOVEMENT OF
THE STORMS WILL LEAD TO A LOCAL HEAVY RAIN THREAT AS WELL.
WILL BE CARRYING LIKELY POPS AROUND 60 PERCENT FOR ONLY THE COUNTIES
ACROSS SOUTH-CENTRAL KANSAS (COMANCHE, BARBER, PRATT)...WITH POPS
RAPIDLY DECREASING TO THE NORTHWEST TO 20 PERCENT FROM ELKHART TO
JETMORE TO HAYS. ONE OR TWO STRONG/SEVERE CLUSTERS WILL PERSIST
THROUGH THE EVENING AND LATE NIGHT MOST LIKELY ALONG THE
KANSAS-OKLAHOMA BORDER SO WILL KEEP HIGHEST POPS ACROSS THE EXTREME
SOUTH (ALONG THE OKLAHOMA BORDER) THROUGH 06Z WITH POPS DECREASING
TO AROUND 20 PERCENT BY DAYBREAK AS THE MAIN CONVECTIVE ACTIVITY
SHIFTS FURTHER SOUTH INTO THE OKLAHOMA-TEXAS PANHANDLES. SOME
REMNANT POST-FRONTAL SHOWERY TYPE PRECIPITATION COULD LINGER ON
THROUGH DAYBREAK ACROSS SOUTHERN COUNTIES WHERE WEAK MID LEVEL
FRONTOGENESIS MAY CONTINUE...BUT THE BULK OF THE ACTIVITY WILL BE
OFF TO THE SOUTH BY THEN.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 353 AM CDT WED JUN 20 2012
AN EXTENDED PERIOD OF WARM AND DRY WEATHER WILL PREVAIL IN THE
CENTRAL UNITED STATES AFTER THE ATMOSPHERE RECOVERS FROM THE
INVASION OF SLIGHTLY COOLER AIR WEDNESDAY AND THURSDAY. ALL OF THE
NUMERICAL MODELS ARE IN EXCELLENT AGREEMENT WITH BUILDING AN UPPER
LEVEL SUBTROPICAL HIGH PRESSURE SYSTEM OVER THE CENTRAL PLAINS
FRIDAY AND SATURDAY AND MAINTAINING THE RIDGE THROUGH THE MIDDLE OF
NEXT WEEK. THIS EVOLUTION IS CONSISTENT WITH LARGE SCALE ENERGY
PROPAGATION FROM TROPICAL THUNDERSTORM ACTIVITY IN THE INDIAN OCEAN,
AND CONFIDENCE IN THIS EVOLUTION IS HIGH. TROPICAL THUNDERSTORM
ACTIVITY REMAINS VERY ACTIVE FROM 60E TO 80E AND APPEARS TO BE BEST
REPRESENTED BY PHASE ONE/TWO OF THE WHEELER HENDON PHASE SPACE
DIAGRAM. MOST OF THE NUMERICAL MODELS INDICATE A COHERENT TROPICAL
CLUSTER WILL PROPAGATE SLOWLY IN THE INDIAN OCEAN THROUGH LATE JUNE,
AND THE ECMWF SEEMS TO BE IN BEST AGREEMENT WITH OBSERVED EVOLUTION
OF TROPICAL THUNDERSTORMS ON SATELLITE IMAGERY. THE GLOBAL RELATIVE
ATMOSPHERIC ANGULAR MOMENTUM HAS DROPPED BELOW THE LONG TERM
AVERAGE, AND THE TENDENCY CONTINUES TO BE NEGATIVE. THE ATMOSPHERE
APPEARS TO BE BE BEST REPRESENTED BY PHASE ONE OF THE WEICKMANN-
BERRY GLOBAL WIND OSCILLATION (GWO) PHASE SPACE DIAGRAM. PHASE ONE
OF THE GWO PHASE SPACE DIAGRAM AND PHASE TWO OF THE WHEELER HENDON
PHASE SPACE DIAGRAM CORRELATE WITH ANTICYCLONIC UPPER LEVEL FLOW
ACROSS THE SOUTHERN UNITED STATES WITH A TENDENCY FOR CYCLONIC FLOW
FROM WESTERN CANADA INTO THE NORTHERN ROCKIES. THE 00Z RUN OF THE
ECMWF IS LESS AMPLIFIED THAN PREVIOUS RUNS WITH THE LONG WAVE TROUGH
NEAR 80W AND IS CLOSER TO THE GFS SOLUTION. THE GFS DEVELOPS A
STRONGER ANTICYCLONE IN THE SOUTHEASTERN UNITED STATES LATE NEXT
WEEK AND BETTER REPRESENTS WHAT WOULD BE EXPECTED FROM THE LARGE
SCALE ATMOSPHERIC FORCING.
BY THE MIDDLE OF NEXT WEEK, THE UPPER LEVEL RIDGE IN THE CENTRAL
UNITED STATES SHOULD BEGIN TO WEAKEN SLIGHTLY. MOST OF THE CANADIAN
ENSEMBLE MEMBERS AND THE GFS DETERMINISTIC SOLUTION SUGGEST
RETROGRESSION OF THE CENTRAL UNITED STATES ANTICYCLONE TO THE
ROCKIES WITH AN UPPER LEVEL CYCLONE NEAR JAMES BAY. WEAKENING OF THE
ANTICYCLONE IN THE CENTRAL PLAINS MAY PROVIDE INCREASED OPPORTUNITY
FOR NORTHWESTERLY FLOW THUNDERSTORM CLUSTERS IN THE CENTRAL PLAINS
BY THE FIRST PART OF JULY, BUT THERE MAY NOT BE MUCH RAINFALL IN
SOUTHWESTERN KANSAS AFTER TONIGHT UNTIL THE END OF JUNE.
IN THE NEAR TERM, MODEL SOUNDINGS CONTINUE TO INDICATE WEAK
INSTABILITY AND MID LEVEL MOISTURE BEHIND THE COLD FRONT IN
SOUTHWEST KANSAS YET THURSDAY MORNING. A WEAK UPPER LEVEL TROUGH
THAT WAS IN NORTHERN NEVADA AT 06Z WILL APPROACH WESTERN KANSAS
THURSDAY MORNING AND MAY PROVIDE ENOUGH UPWARD VERTICAL MOTION IN
THE MID LEVEL BAROCLINIC ZONE TO SUPPORT A FEW HIGH BASED
SHOWERS/VIRGA THURSDAY MORNING NEAR THE OKLAHOMA BORDER. IT IS NOT
OUT OF THE REALM OF POSSIBILITY THAT A FEW THUNDERSTORMS COULD FORM
IN THE HIGHER TERRAIN IN EASTERN COLORADO NEAR THE OLD FRONTAL
BOUNDARY THURSDAY AFTERNOON WITH THE RETURN OF MOIST UPSLOPE FLOW,
AND AN ISOLATED THUNDERSTORM COULD REACH FAR SOUTHWEST KANSAS EARLY
THURSDAY EVENING. THE ELEVATED MIXED LAYER WILL SPREAD EASTWARD INTO
KANSAS THURSDAY NIGHT, AND SOME ALTOCUMULUS WITH VIRGA OR LIGHT
SHOWERS ARE POSSIBLE IN THE MID LEVEL FRONTOGENETIC ZONE LATE
THURSDAY NIGHT. CONFIDENCE IN MEASURABLE RAINFALL IS LOW,
HOWEVER.
VERY HOT AIR IN THE MID LEVELS OF THE ATMOSPHERE WILL COVER KANSAS
THROUGH THE FIRST PART OF NEXT WEEK. AN ISOLATED THUNDERSTORM IS
POSSIBLE ALONG THE LEE TROUGH IN EASTERN COLORADO IN THE LATE
AFTERNOON HOURS, BUT ANYTHING THAT FORMS WILL BE SHORT LIVED AND
PROBABLY WILL NOT MOVE MUCH. AN UPPER LEVEL TROUGH MOVING OVER THE
CENTRAL UNITED STATES RIDGE WILL SUPPORT THUNDERSTORM DEVELOPMENT
ALONG THE EAST SIDE OF THE ELEVATED MIXED LAYER FRIDAY NIGHT, BUT
THESE THUNDERSTORMS LIKELY WILL REMAIN WELL TO THE EAST OF HAYS. A
WEAK COLD FRONT WILL MOVE TO NEAR THE KANSAS/NEBRASKA BORDER SUNDAY
AND REMAIN NEARLY STATIONARY MONDAY. CONVERGENCE ALONG THE BOUNDARY
MAY SUPPORT DEVELOPMENT OF AN ISOLATED THUNDERSTORM EVEN WITH
EXTREMELY WARM TEMPERATURES ALOFT, BUT ANYTHING THAT DOES FORM
LIKELY WILL REMAIN NORTH OF INTERSTATE 70. TEMPERATURES WILL RISE TO
NEAR 100 DEGREES SATURDAY THROUGH TUESDAY WITH ONLY MINOR DAY TO DAY
VARIATIONS. SOME TEMPERATURES NEAR 105 ARE POSSIBLE, ESPECIALLY IN
NORTHERN KANSAS WHERE RAINFALL HAS BEEN ESPECIALLY LIMITED IN RECENT
WEEKS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1221 PM CDT WED JUN 20 2012
A COLD FRONT STRETCHES FROM HUGOTON TO JUST WEST OF KGCK AND SCOTT
CITY WITH A PRE-FRONTAL TROUGH WIND SHIFT EAST OF THAT LINE NEAR
LIBERAL TO KGCK TO DIGHTON. EXPECT WINDS TO SHIFT NORTH AND
INCREASE TO 20 TO 25 KTS AT KDDC AND KHYS BETWEEN 19 TO 21Z WITH
THE COLD FRONT. THE LATEST RAP FORECAST SHOWS A LINE OF
THUNDERSTORMS BEGINNING AROUND 21Z FROM KHYS TO KDDC AND KLBL.
OTHER SHORT TERM MODELS KEEP THE LINE OF STORMS JUST EAST OF THE
TAF SITES. FOR NOW WITH THE SOUNDING SHOWING A STRONG CAPPING
INVERSION WILL CONTINUE TO KEEP THUNDER OUT OF THE FORECAST AND
JUST TO THE EAST. CIGS COULD LOWER BRIEFLY TO MFVR CONDITIONS
AROUND 03-05Z OTHERWISE VFR CONDITIONS ARE EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 92 63 84 61 / 20 20 10 10
GCK 90 62 83 59 / 10 10 10 10
EHA 90 62 81 64 / 10 20 20 10
LBL 93 64 83 62 / 20 30 20 10
HYS 88 61 85 58 / 10 20 10 10
P28 94 69 85 62 / 30 50 20 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 1 PM CDT THIS AFTERNOON FOR KSZ031-046-
064>066-078>081-086>090.
&&
$$
SYNOPSIS...UMSCHEID
SHORT TERM...UMSCHEID
LONG TERM...RUTHI
AVIATION...KRUSE
AREA FORECAST DISCUSSION
NWS JACKSON KY
140 PM EDT WED JUN 20 2012
.UPDATE...
ISSUED AT 140 PM EDT WED JUN 20 2012
ISOLATED CONVECTION HAS REMAINED IN VA SO FAR EARLY THIS
AFTERNOON...BUT STILL EXPECT ISOLATED CONVECTION TO DEVELOP OVER SE
KY. CUMULUS FIELD HAS BECOME A LITTLE MORE EXTENSTIVE AND HAVE
UPDATED NDFD WITH WITH LATEST OBSERVATIONAL TRENDS.
UPDATE ISSUED AT 1136 AM EDT WED JUN 20 2012
12Z NAM AND HRRR CONTINUE TO POINT TOWARDS CONVECTION INITIATING
ALONG THE HIGHER TERRAIN NEAR THE VA BORDER EARLY THIS AFTERNOON WITH
A SLIGHT CHANCE FURTHER NW BY MID TO LATE AFTERNOON. THE 09Z SREF
ALSO SUPPORTING THIS. 1515Z VISIBLE SATELLITE SHOWS CU FORMING OVER
THE BLACK MOUNTAIN AREA OF HARLAN COUNTY WITH CU EXTENDING ON INTO
WISE COUNTY VA...SO FORECAST LOOKS ON TRACK AT THIS POINT. MADE MINOR
UPDATE TO NDFD FOR LATEST OBSERVATIONAL TRENDS.
UPDATE ISSUED AT 953 AM EDT WED JUN 20 2012
HAVE UPDATED NDFD AND ASSOICATED PRODUCTS TO EXPAND THE 20 PERCENT
CHANCE OF THUNDERSTORMS ACROSS THE FORECAST AREA FOR THIS AFTERNOON.
THIS IDEA IS SUPPORTED BY THE 06Z NAM AND 10Z HRRR. CONVECTION MAY
FIRST INITIATE ALONG THE HIGHER TERRAIN NEAR THE VA BORDER IN EARLY
AFTERNOON...WITH THE ISOLATED CONVECTION THEN BECOMING POSSIBLE
FURTHER NW DURING THE MIDDLE TO LATE AFTERNOON.
UPDATE ISSUED AT 659 AM EDT WED JUN 20 2012
SOME PATCHY FOG SHOWING UP IN A FEW OBSERVATIONS WITH VISIBILITIES IN
THE 5-6 MILE RANGE. FOG ALREADY MENTIONED IN THE FORECAST. TEMPS ON
TRACK AND GRIDS HAVE BEEN REFRESHED FOR THE MOST RECENT OBS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 250 AM EDT WED JUN 20 2012
SFC AND 50H HIGH OVER THE APPALACHIANS WILL SHIFT TO THE COAST AS A
COLD FRONT APPROACHES THE OHIO VALLEY. THE RIDGE WILL BE REPLACED BY
A 50H TROF FROM THE GREAT LAKES TO FLA. MODELS WERE IN GOOD AGREEMENT
THAT THE FRONT WOULD ENTER EASTERN KY EARLY FRIDAY WITH THE BULK OF
THE PCPN EXPECTED WITH AND BEHIND THE FRONT. SEVERAL DAYS OF
SOUTHWEST FLOW HAS PUSHED DEWPOINTS INTO THE UPPER 60S AS EVIDENCED
BY NIGHTLY VALLEY FOG. WITH THE APPROACHING FRONT EXPECT AN INCREASE
IN AFTERNOON SHOWERS AND THUNDERSTORMS ACROSS THE FORECAST AREA.
THESE STORMS WILL BE INITIALLY LOCATED IN THE EASTERN COUNTIES THIS
AFTERNOON AND THEN MORE WIDESPREAD ON THU BEFORE THE FRONT ARRIVES ON
FRIDAY. TEMPERATURES HAVE BEEN HARD PRESSED TO RISE MUCH ABOVE THE 90
DEG MARK WITH ALL THE GREEN FORESTS IN EASTERN KY. EXPECT THIS TREND
TO CONTINUE WITH HIGHS IN THE UPPER 80S TO AROUND 90 BOTH TODAY AND
THU BEFORE FALLING SLIGHTLY TO JUST THE UPPER 80S ON FRI WITH THE
INCREASE IN CLOUD COVER PRECEEDING THE FRONTAL BOUNDARY. OVERNIGHT
LOWS WILL FALL TO AROUND 70 EACH NIGHT WITH LOWER 70S PREVALENT ON
THE RIDGES AS THE COOLER AIR SINKS INTO THE VALLEYS AFTER SUNSET.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 258 AM EDT WED JUN 20 2012
THE EXTENDED FORECAST PERIOD BEGINS ON FRIDAY NIGHT WITH MERIDIONAL
AND UNSEASONAL AMPLIFIED PATTERN FOR THIS TIME OF YEAR. A
STRENGTHENING RIDGE DEVELOPS OVER THE CENTRAL PLAINS AS BROAD TROUGH
TAKES SHAPE OVER THE EASTERN CONUS AND ALONG THE CANADIAN MARITIMES.
A DEVELOPED AND STRENGTHENING CLOSED LOW OVER THE HUDSON BAY REGION
WILL SEND DOWN SEVERAL SHORTWAVES DURING THE REST OF THE EXTENDED.
AFTER A BRIEF SHORTWAVE RIDGE ON SATURDAY...A STRONGER SHORTWAVE
TROUGH DIVES SOUTH THROUGH THE DAKOTAS AND MN INTO THE OHIO VALLEY
BY SUNDAY. BY TUESDAY...THE CLOSED LOW OVER THE GREAT LAKES FINALLY
DROPS SOUTH INTO THE MID ATLANTIC AND NEW ENGLAND STATES BUT REMAINS
NEARLY STATIONARY THROUGH THE END OF THE EXTENDED AS A BLOCKING
PATTERN LOOKS TO SET UP.
THE INITIALIZATION CAME IN WITH A REASONABLE SET UP FOR POPS WITH
SOME SLIGHT CHANCE IN THE EASTERN COUNTIES BORDERING VA WITH THE
EXITING FRONT FRIDAY NIGHT. THE NEXT FRONT WILL MOVE THROUGH ON
SUNDAY PROVIDING A SLIGHT CHANCE OF PRECIP. WHILE THE FORCING AND
INSTABILITY ARE THERE...ONCE AGAIN THE AMOUNT OF MOISTURE IS OF A
CONCERN AS SOME SHOWER AND THUNDERSTORM ACTIVITY WILL DEVELOP FOR
SUNDAY THROUGH MONDAY...BUT COVERAGE WILL BE FEW AND FAR BETWEEN
COMPLICATING THE DRY CONDITIONS THAT HAVE DEVELOPED IN CERTAIN AREAS
OF EASTERN KENTUCKY. BY TUESDAY...GOOD SUBSIDENCE AND DRY MID LEVELS
HAVE EDGED FAR ENOUGH EAST TO BASICALLY KEEP PRECIP OUT OF EASTERN
KENTUCKY FOR THE REST OF THE EXTENDED AND POSSIBLY EVEN LONGER PAST
DAY 7. BY TUESDAY...THE AFOREMENTIONED UPPER LEVEL CLOSED LOW SLIDES
SOUTH AS A COLD FRONT PUSHES SOUTH THROUGH THE OHIO VALLEY.
HOWEVER...THIS LOOKS TO BE A DRY FRONT AS THE BULK OF THE MOISTURE
AND BETTER DYNAMICS STAYS TO THE NORTH AND EAST PROLONGING THE DRY
PERIOD OVER THE FA. ON A GOOD NOTE...THE PROLONGED TROUGH OVER THE
EASTERN CONUS CUTS OFF THE FLOW FROM THE SOUTH AND INTO A MORE
NORTHWEST FLOW. THIS PUTS HIGH TEMPERATURES ACROSS THE AREA RIGHT
AROUND NORMAL IN THE LOW 80S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 140 PM EDT WED JUN 20 2012
OTHER THAN SOME LIGHT FOG DEVELOPING RIGHT ALONG THE RIVERS AND OTHER
BODIES OF WATER LATE TONIGHT...VFR CONDITIONS WILL CONTINUE. FOG
TONIGHT IS NOT FORECAST TO AFFECT ANY OF THE TAF SITES. WITH DAY TIME
HEATING ISOLATED THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON AND
EARLY EVENING...AND AGAIN ON THURSDAY AFTERNOON. COVERAGE WILL BE
VERY LIMITED AND WILL LEAVE OUT OF TAFS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...DUSTY
LONG TERM....SHALLENBERGER
AVIATION...SBH
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
409 PM EDT WED JUN 20 2012
.SYNOPSIS...
VERY WARM DAY ON THURSDAY WILL PRECEDE A WEAK COLD FRONT MOVING
THROUGH THE MID OHIO VALLEY ON THURSDAY NIGHT AND FRIDAY MORNING.
THIS FRONT WILL BRING A THREAT OF SHOWERS AND STORMS...BUT RAIN IS
NOT EXPECTED TO BE WIDESPREAD OR PARTICULARLY HEAVY OUTSIDE OF
TYPICAL SUMMERTIME DOWNPOURS. THE FRONT WILL SETTLE SOUTH OF THE
AREA FRIDAY AFTERNOON WITH COOLER AIR MOVING IN FOR THE UPCOMING
WEEKEND. WHILE A SMALL THREAT OF PRECIPITATION WILL DEVELOP LATER
IN THE WEEKEND...MOST AREAS ARE EXPECTED TO REMAIN DRY WITH
COOL TEMPERATURES CONTINUING INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
AT 19Z...MSAS CONTINUED TO DEPICT A RATHER LARGE/BROAD SURFACE
HIGH PRESSURE SYSTEM OVER WV MOUNTAINS /1021MB/ WITH WEAK SWLY
FLOW OVER THE WFO ILN FORECAST AREA. 850MB TEMPS OF 17C AS
SAMPLED BY 20.12Z KILN RAOB HAD LIKELY WARMED TO AROUND 19C VIA
WEAK WARM ADVECTION VIA RUC ANALYSIS - AND SUPPORTED HIGHS TODAY
IN THE LOWER 90S. DEWPOINTS CONTINUE TO MIX OUT AND ACTUALLY
CAUSING HEAT INDEX VALUES TO COME IN SAME OR LESS THAN AIR
TEMPERATURE...INDICATIVE THAT SURFACE MOISTURE IS NOT SUBSTANTIAL
THIS AFTERNOON. SO FAR...DEEPER CUMULUS HAS DEVELOPED RIGHT WHERE
HI-RES CONVECTION ALLOWING 4KM GUIDANCE SAID IT WOULD /NEAR PMH/
BUT MIXING DEWPOINTS LIKELY INHIBITING FURTHER GROWTH THUS FAR.
WILL HOLD THE LOW RAIN CHANCE IN THE FAR SOUTH INTO EARLY
EVENING...BUT UNLESS CUMULUS SHOWS MORE DEPTH IN NEXT HOUR OR
TWO...WILL LIKELY PULL THIS RAIN CHANCE SOONER THAN LATER.
OVERNIGHT...DEEPER MOISTURE POOL /SHOWN NICELY ON SATELLITE
BLENDED PWAT AND RUC ANALYSIS/ OFF TO OUR SOUTH/EAST WILL CONTINUE
TO ROTATE UP THE EAST SIDE OF THE FORECAST AREA. THIS MAY BRING A
FEW MORE CLOUDS OVER PREVIOUS NIGHTS TO THE EASTERN AREAS BUT BY
AND LARGE SKIES SHOULD AGAIN GO CLEAR QUICKLY THIS EVENING. LITTLE
MORE FLOW IN THE LOWEST 1KM TONIGHT OUT OF THE SOUTHWEST /WARM
ADVECTION/ SO WILL RUN MIN TEMPS A LITTLE WARMER IN MOST AREAS
THAN LAST. THOUGHT ABOUT A LOW RAIN CHANCE FOR CNTL OH LATER ON
FOR AN ELEVATED STORM WITHIN THAT DEEPER MOISTURE PLUME...BUT LOW
LEVEL JET AND CONVERGENCE NOT AT ALL IMPRESSIVE SO WILL HOLD DRY
THROUGH THE NIGHT.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
FEATURES OF IMPORTANCE IN THIS PERIOD ARE THE STRONG DEEP LAYERED
RIDGE OVER THE MID ATLANTIC...AND UPPER TROUGH OVER THE CENTRAL
CONUS PUSHING EAST. BY 12Z THURSDAY...CENTER OF 591DM 500MB
ANTICYCLONE WILL BE OVER WASHINGTON DC AREA WITH RATHER SHARP
UPPER TROUGH AXIS JUST EAST OF THE MS RIVER. SHORTWAVE
DYNAMICS/JET ENERGY HOWEVER WILL BE PULLING NORTHEAST THROUGH
ONTARIO...THUS A GLANCING BLOW OF MID/UPPER LEVEL FORCING AND PV
FROM THIS WAVE BY THE TIME IT ARRIVES LATER THURSDAY EVENING.
HEIGHT FALL CENTER WELL TO THE NORTH OF THE AREA...BUT ENOUGH
PROGRESSION OF THE FALLS TO ALLOW THE RATHER DEFINED /INITIALLY/
COLD FRONT TO PROGRESS QUICKLY FROM THE WESTERN GREAT LAKES INTO
THE INDIANA/OHIO BY LATER THURS AFTN AND EVE. THIS WILL PUSH DEEP
LAYERED RIDGE OFF THE ATLANTIC COAST BY 22.00Z.
20.12Z NAM/ECMWF BOTH IN VERY GOOD AGREEMENT THAT CORRIDOR OF
RATHER DEEP/DRY AIR WILL DEVELOP AMIDST SUBSIDENCE/COMPRESSIONAL
WARMING AHEAD OF THE FRONT. BOTH DATA SETS SUGGEST NARROW 850MB
TEMP AXIS UP TO 20/21C DEVELOPING COINCIDENT TO THE DRYING OVER
THE FORECAST AREA. WITH GUIDANCE /STATISTICAL MOS AND RAW DATA/
SHOWING SURFACE AND ML DEWPOINTS DROPPING IN THIS ZONE...THINK A
WINDOW OF HIGHER HEAT DEVELOPS TOMORROW BETWEEN THE LOBE OF HIGH
PWAT OFF TO OUR EAST...AND INCOMING FRONTAL BOUNDARY. THUS HAVE
INCREASED MAX T IN THE FORECAST...NOW RUNNING MID 90S MUCH OF
SRN/ERN FORECAST AREA INCLUDING CMH/CVG. WOULD CONSIDER HEAT
HEADLINES...BUT BLENDED DEWPT FORECAST YIELDS 59-63 DEWPOINTS
WHICH ACTUALLY REDUCED APPARENT TEMP NUMBERS IN THE GRIDS...SO NO
HEAT HEADLINES.
20.12Z DATA SETS A LITTLE MORE INTACT WITH THE LOW LEVEL FGEN
CIRCULATION ATTENDANT TO THE ADVANCING COLD FRONT...AND SUBSEQUENT
LOW LEVEL VERTICAL MOTION FIELD AND MOISTURE CONVERGENCE. DESPITE
THE FACT FRONT WILL BE SLOWING A LITTLE...AND BOUNDARY LAYER
MOISTURE WILL OVERALL BE MEAGER...FEEL A SCT-BKN BAND OF MULTICELL
STORMS /WEEK DEEP SHEAR THUS LITTLE STORM ORGANIZATION/ WILL
DEVELOP/MOVE INTO WESTERN AREAS BY EVENING. THINK WESTERN AREAS
SEE THE BEST CHANCE OF THESE STORMS THUS MINOR UPGRADE IN RAIN
CHANCES PER 20.15Z SREF/NMM/ARW-WRF...BUT FEEL THIS ACTIVITY WILL
QUICKLY BECOME OUTFLOW DOMINATED /PER WEAK LOW LEVEL FLOW/ AND
GUST OUT...THUS HAVE RAIN CHANCES DIMINISHING FROM NW TO SE THURS
NIGHT AS DYNAMICS/STRONGER WIND FIELDS ALOFT CONTINUE TO PULL AWAY
AND DIURNAL/INSTABILITY COMPONENT WANES. FGEN CIRCULATION WEAKENS
AS WELL WITH TIME.
DON/T FEEL SEVERE THREAT ALL THAT HIGH...MLCAPES PER 4KM NAM-WRF
NEST BUFR SOUNDINGS AND SREF PLUMES STRUGGLE TO EXCEED 1000
J/KG...BUT THINKING HOT/DEEPLY MIXED BOUNDARY LAYER /INVERTED V
SOUNDINGS AND LARGE DCAPE/ MAY PROMOTE A FEW WIND GUST REPORTS AS THE
BIGGEST STORMS COLLAPSE EARLY IN THE LIFE CYCLE OF THE EVENT. MAY
HAVE A WARNING OR TWO...BUT DON`T ANTICIPATE WIDESPREAD SVR NOR
ANY SIGNIFICANT REPORTS. ALSO DON/T FEEL RAIN COVERAGE WILL BE
HIGH AND/OR SIGNIFICANT ENOUGH TO DETER DRYING THAT CONTINUES TO
SLOWLY WORSEN...ESPECIALLY NRN FORECAST AREA.
FRONT A LITTLE SLOWER TO CLEAR THE AREA ON FRIDAY AND INSTBY MAY
BUILD JUST ENOUGH IN THE FAR SOUTH/EAST ON FRIDAY MORNING TO
WARRANT A SMALL RAIN CHANCE. TEMPS A LITTLE TRICKIER BUT FEEL
WE/LL CARVE A GOOD 10F OFF THURSDAYS HIGHS IN MOST AREAS.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
THE HEADLINE FOR THE LONG TERM PERIOD IS THAT THERE DOES NOT APPEAR
TO BE ANY SUBSTANTIAL RAIN MAKER IN THE OFFING. THE UPPER LEVEL FLOW
PATTERN WILL BEGIN TO AMPLIFY THIS WEEKEND AS A DEEP CLOSED LOW
MOVES ONTO THE PACNW COAST...SURGING THE MIDCONTINENT RIDGE INTO
CANADA AND A CLOSED LOW OVER HUDSON BAY SOUTHEAST TOWARD NEW
ENGLAND. THIS WILL PLACE THE AREA IN NORTHWEST FLOW ALOFT FOR MUCH
OF THE PERIOD AS THE RIDGE REMAINS DOMINANT OVER THE PLAINS DESPITE
SOME MOVEMENT OF THE CLOSED LOWS.
SATURDAY WILL FEATURE DRY AND SEASONABLY WARM WEATHER WITH SFC HIGH
PRESSURE IN CONTROL. ALL MODELS HAVE BACKED OFF ON ANY SORT OF
MCS...SO HAVE REMOVED PCPN CHANCES FROM SATURDAY NIGHT. SUNDAY WILL
CONTINUE THIS THEME...ALTHOUGH THE FIRST SHORTWAVE TROUGH ASSOCIATED
WITH THE CLOSED LOW WILL BEGIN TO DIP TOWARD THE EASTERN GREAT
LAKES. INTRODUCED 20 POPS INTO THE NORTH/EAST TO ACCOUNT FOR THIS.
ANOTHER SPOKE OF ENERGY WILL PUSH A WEAK COLD FRONT SOUTH INTO THE
AREA SUNDAY NIGHT AND EARLY MONDAY...SO CONTINUED TO SINK THE 20
POPS SOUTH THROUGH THE AREA (WHICH ARE BELOW POP THRESHOLD FOR THE
WORDED FORECAST). COOLER AIR WILL SLOWLY SEEP SOUTHWARD MONDAY AND
MONDAY NIGHT.
BEYOND THIS...MODELS HAVE BEEN INCONSISTENT IN RESOLVING THE BLOCKY
PATTERN...AND ANOMALOUSLY LOW 500 MB HEIGHTS OVER EASTERN NORTH
AMERICA. ALSO FACTORING INTO THE DILEMMA IS A POSSIBLE TROPICAL
SYSTEM ALONG THE SOUTHEAST COAST. THE PAST FEW RUNS OF THE GFS HAVE
BEEN ON THE DEEP AND SOUTHERN SIDE OF THE ENVELOPE...SO HAVE
DISCOUNTED ITS COOL (60S) TEMPERATURES FOR TUESDAY. HOWEVER...NAEFS
1000-500 MB THICKNESS PLUMES SHOWED AGREEMENT ON TUESDAY HAVING THE
LOWEST VALUES OF THE EXTENDED...YET WITH THE HIGHEST ENSEMBLE
SPREAD. SO TOOK A BLEND OF HPC/00Z ECMWF AND SHAVED OFF A FEW
DEGREES TO ACCOUNT FOR POSSIBLE COOLER SOLUTIONS (YIELDING 75-80).
REGARDLESS OF TEMPERATURES...IT WILL FEEL CRISP COMPARED TO RECENT
WEATHER AS DRY NORTHERLY FLOW DROPS DEW POINTS INTO THE 40S.
WEDNESDAY WILL SHOW SLIGHT MODERATION TO TEMPERATURES AS THE LOW
PULLS A LITTLE TO THE NORTHEAST. WHILE ITS NOT OUT OF THE QUESTION
FOR SOME PCPN TO ROTATE AROUND THE LOW AT SOME TIME EARLY NEXT WEEK
(PARTICULARLY FOR THE NORTHEASTERN CWA)...HAVE KEPT THE FORECAST DRY
FOR NOW WITH NOTHING SUBSTANTIAL TO FOCUS ON.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
CENTER OF UPPER LEVEL RIDGE OVER THE UPPER OHIO VALLEY WILL MOVE
SOUTHEAST TO A POSITION OFF THE CAROLINA COAST BY THURSDAY
EVENING. MEANWHILE...A MID LEVEL TROUGH WILL DIG INTO THE WESTERN
GREAT LAKES. AN ATTENDANT COLD FRONT WITH THE MID LEVEL TROUGH
WILL PUSH ACROSS THE TAF SITES THURSDAY EVENING/NIGHT.
AN INSTABILITY DRIVEN SHOWER OR STORM IS EXPECTED TO REMAIN EAST
AND SOUTH OF THE TAF SITES THROUGH THIS AFTERNOON.
THUS...DIURNALLY DRIVEN CUMULUS CLOUDS WILL DISSIPATE THIS EVENING
WITH SOME FEW-SCT MID AND HIGH LEVEL CLOUDS LINGERING OVERNIGHT
NEAR THE EASTERN TAF SITES. KLUK WILL LIKELY EXPERIENCE SHALLOW
RIVER FOG AGAIN TONIGHT AND HAVE ACCOUNTED FOR THIS BY EMPLOYING
PREDOMINATE MVFR VSBYS WITH LOCAL IFR VSBYS. FOG SHOULD BURN OFF
BY 12Z.
LOOKS LIKE TAF SITES WILL BE PCPN FREE FOR A GOOD PART OF
THURSDAY UNTIL A COLD FRONT MOVES IN FROM THE WEST LATE IN THE DAY
AND MOVES EAST/SOUTHEAST THROUGH THE REGION THURSDAY NIGHT. THERE
SHOULD BE ENOUGH INSTABILITY AND LOW LEVEL FRONTAL CONVERGENCE FOR
SCATTERED CONVECTION ALONG THE FRONT. THUNDERSTORM CHANCES START TO
INCREASE TOWARD 00Z AS THE FRONT APPROACHES.
OUTLOOK...THUNDERSTORMS POSSIBLE THURSDAY NIGHT.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...BINAU
NEAR TERM...BINAU
SHORT TERM...BINAU
LONG TERM...SNYDER
AVIATION...HICKMAN
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
139 PM EDT WED JUN 20 2012
.SYNOPSIS...
STRONG RIDGE OF HIGH PRESSURE OVER THE OHIO VALLEY WILL MOVE OFF THE
CAROLINA COAST ALLOWING A COLD FRONT TO PUSH ACROSS THE AREA LATE
THURSDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FOR 930 AM UPDATE...HAVE MADE A SMALL ADJUSTMENT TO SKY GRIDS TO
ALLOW FOR A LITTLE CU TO DEVELOP. MODELS DIFFER ON WHERE THEY THINK
BETTER 850 MB MOISTURE WILL BE THIS AFTERNOON. ADDED CONVERGENCE
FROM LAKE BREEZE SHOULD AID CU DEVELOPMENT IN THE EASTERN PART OF
THE SNOWBELT. HRRR LATEST RUN NOW DEVELOPS A FEW LIGHT CELLS IN THE
AREA OF WHERE THE LAKE BREEZE CONVERGENCE OCCURS WHILE THE RUN FROM
THE PREVIOUS HOUR HAD SOME ISOLATED LIGHT CELLS SPREAD IN THE SOUTH
AND SE PART OF THE AREA. THINK CAP AT MID LEVELS WILL KEEP ANY
PRECIP FROM DEVELOPING SO WILL KEEP POP BELOW 10%.
TEMPS AND DEWPOINTS SEEM IN LINE SO HEAT INDEX SHOULD STAY JUST
UNDER THRESHOLD NEEDED FOR HEAT ADVISORY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
MODELS IN GOOD AGREEMENT MOVING COLD FRONT INTO NW OH THURSDAY
AFTERNOON AND PUSHING SOUTH OF THE AREA THURSDAY NIGHT. BEST CHANCE
FOR PRECIP LATE AFTERNOON INTO THE EVENING HOURS. SPC HAS AREA IN A
SEE TEXT. CAPES APPROACH 1500 J/KG...BUT VERY LITTLE SHEAR AND
LIMITED MOISTURE.
MUCH COOLER AND DRIER MUCH MORE SEASONAL CONDITIONS RETURN FOR
FRIDAY AND SATURDAY.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
OVERALL THE MODELS ARE FAIRLY SIMILAR BUT SOME DIFFERENCES DO CROP
UP LATE IN THE PERIOD. A WEAK COLD FRONT WILL MOVE ACROSS THE
REGION LATE SUNDAY INTO SUNDAY NIGHT. WILL NEED A MENTION OF PRECIP
WITH THIS FEATURE. HIGH PRESSURE WILL BEGIN TO BUILD OVER THE
REGION FROM NORTHWEST ON MONDAY. 850 MB TEMPS WILL DIP TO THE UPPER
SINGLE DIGITS SO HIGH TEMPS WILL BE A LITTLE BELOW NORMAL BOTH
MONDAY AND TUESDAY. THE MODELS TRACK AN AREA OF LOW PRESSURE UP THE
EAST COAST EARLY NEXT WEEK. THE ECMWF IS A LITTLE FURTHER WEST THAN
THE GFS. AS A RESULT THE ECMWF BRINGS PRECIP INTO THE EASTERN END
OF THE FORECAST AREA. THE GFS KEEPS THE AREA MAINLY DRY. GIVEN THE
FACT THAT PRECIP IS ALREADY IN THE FORECAST WILL CONTINUE WITH A
SMALL MENTION TUESDAY ACROSS FAR NE OH AND NW PA.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
VFR CONDITIONS WILL CONTINUE. FEW/SCT FAIR WEATHER CUMULUS WILL
GRADUALLY DIMINISH LATE THIS AFTERNOON AND EARLY THIS
EVENING...THEN IT WILL BE CLEAR. THE SOUTH TO SOUTHWEST BREEZE
WILL BE A BIT GUSTY AT TIMES THIS AFTERNOON. THERE WILL PROBABLY
BE JUST ENOUGH OF A SOUTH BREEZE TONIGHT TO KEEP ANY FOG OR HAZE
FROM FORMING.
.OUTLOOK...NON VFR POSSIBLE IN SCATTERED SHOWERS AND THUNDERSTORMS
THURSDAY EVENING AND NIGHT.
&&
.MARINE...
QUIET WEATHER WILL CONTINUE ON THE LAKE THE NEXT COUPLE OF DAYS. S
TO SW FLOW GENERALLY IN THE 5 TO 15 KNOT RANGE WILL CONTINUE TILL A
COLD FRONT CROSSES LAKE ERIE SOMETIME LATE THURSDAY. ONSHORE FLOW
IS LIKELY IN THE NEARSHORE WATERS DURING THE AFTERNOON. THE FLOW
WILL BECOME W TO NW BEHIND THE FRONT WITH SPEEDS INCREASING TO
AROUND 15 KNOTS. MAY COME CLOSE TO NEEDING A SMALL CRAFT ADVISORY.
NW TO N FLOW AT UNDER 15 KNOTS CAN BE EXPECTED FROM FRIDAY INTO LATE
SATURDAY. HIGH PRESSURE WILL MOVE OVERHEAD SUNDAY WITH MAINLY LIGHT
AND VARIABLE FLOW. STRONG TO POSSIBLY SEVERE STORMS COULD OCCUR
LATE THURSDAY ALONG AND AHEAD OF THE COLD FRONT.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...DJB
NEAR TERM...DJB
SHORT TERM...DJB
LONG TERM...KUBINA
AVIATION...KOSARIK
MARINE...KUBINA
AREA FORECAST DISCUSSION
NWS NORMAN OK
257 PM CDT WED JUN 20 2012
.DISCUSSION...
A FEW SHOWERS AND STORMS MAY DEVELOP ACROSS SOUTH CENTRAL AND
SOUTHEAST OKLAHOMA THROUGH THE LATE AFTERNOON...BUT SHOULD
DISSIPATE QUICKLY DURING THE EARLY EVENING. A BETTER CHANCE FOR
STORM DEVELOPMENT WILL BE OVER NORTHWEST OKLAHOMA THIS EVENING
AS A COLD FRONT APPROACHES
HIGH RESOLUTION MODELS DEVELOP CONVECTION AROUND 6 OR 7 PM ACROSS
FAR NORTHWEST OKLAHOMA WITH ADDITIONAL STORMS FORMING ALONG THE
FRONT DURING THE EVENING AND OVERNIGHT. RATHER WARM MID-LEVEL
TEMPS WHERE OBSERVED ACROSS THE HIGH PLAINS THIS MORNING
+ 16-17 AT DDC/AMA...WHICH MAY LIMIT THE NUMBER OF STORMS. A
RECENT RUN OF THE HRRR WEAKENS CONVECTION OUT WEST...WITH BETTER
CHANCES FOR STORMS ACROSS NORTH CENTRAL OKLAHOMA. THIS SEEMS LIKE
A PLAUSIBLE SOLUTION.
STORMS/SHOWERS MAY DEVELOP AS FAR SOUTH AS CENTRAL OKLAHOMA DURING
THE OVERNIGHT EARLY THURSDAY MORNING...BUT THE OVER COVERAGE OF
PRECIPITATION SHOULD DECREASE AS THE FRONT MOVES SOUTH AND WEAKENS.
MODELS STILL BUILD A RATHER IMPRESSIVE RIDGE OVER THE SOUTHERN
PLAINS DURING THE WEEKEND. TRIPLE DIGIT HEAT WILL LIKELY RETURN
TO SOME AREAS...ESPECIALLY LOCATIONS THAT HAVE BEEN LESS FORTUNATE
WITH RAINFALL AMOUNTS OVER THE PAST 30-60 DAYS. THE OFFSHOOT WILL
BE TRIPLE DIGIT HEAT INDEX VALUES WITH HIGHS IN THE UPPER 90S.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 71 87 68 89 / 30 40 20 0
HOBART OK 69 89 68 92 / 30 50 20 10
WICHITA FALLS TX 71 94 71 95 / 10 30 20 10
GAGE OK 64 86 60 91 / 60 30 10 0
PONCA CITY OK 68 85 63 88 / 60 40 10 0
DURANT OK 71 92 71 92 / 10 20 20 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
117 PM EDT WED JUN 20 2012
.SYNOPSIS...
SURFACE HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH THE DAY
THURSDAY...A WEAKENING COLD FRONT WILL THEN APPROACH FROM THE
NORTHWEST FRIDAY AND MOVE THROUGH THE AREA SATURDAY.
&&
.NEAR TERM /THROUGH THURSDAY/...
AS OF 1 PM EDT...FORECAST MONITOR IS ALL GREEN WITH ALL PARAMATERS
WITHIN TOLERANCE...SO NO GRID CHANGES NEEDED. NO CONVECTION HAS
FIRED YET IN OUR CWA...BUT STILL EXPECT WIDELY SCATTERED COVERAGE
BY MID-AFTERNOON OVER THE NC MOUNTAINS.
PREVIOUS DISCUSSION:
CURRENT FORECAST LOOKS RIGHT ON TRACK. FORECAST SOUNDINGS SHOW WARM
MID LEVELS WHICH RESULTS IN MEAGER LAPSE RATES. RAP SOUNDINGS
INDICATE THAT PIEDMONT AREAS SHOULD REMAINED CAPPED...BUT MOUNTAIN
LOCATIONS SHOULD BREAK THE CAP WITH HEATING WITH CAPES IN THE
500-1000J RANGE. GFS AND NAM LOOK OVERDONE ON THE CONVECTIVE
COVERAGE THIS AFTERNOON. MESOMODELS LOOK MORE REASONABLE WITH JUST
WIDELY SCATTERED/SCATTERED CONVECTION. HOWEVER, WILL DISREGARD THE
ISOLD CONVECTION OF HRRR OVER THE PIEDMONT. THE UPSHOT IS THAT WE
WILL STAY THE COURSE WITH WIDELY SCATTERED TYPE POPS CONFINED TO THE
MOUNTAINS FOR THIS AFTERNOON.
PREVIOUS DISCUSSION...
FOR TODAY...THE CENTER OF THE LARGE UPPER RIDGE WILL SLIDE JUST TO
OUR NORTH AND THEN BEGIN TO DAMPEN AS A NORTHERN STREAM UPPER TROF
APPROACHES THE GREAT LAKES EARLY THURS. AT THE SFC...HIGH PRESSURE
WILL PERSIST THRU THE PERIOD BUT SLIDE A BIT FARTHER EAST CAUSING
OUR LOW LVL WINDS TO BECOME MORE SELY THIS AFTERNOON/EVENING.
OTHERWISE...THE SENSIBLE FCST WILL BE VERY SIMILAR TO THE PAST FEW
DAYS WITH A SLIGHT CHANCE POP OVER THE NC MTS FOR SCT TO ISO TSRA
AND A SOLID CHANCE ALONG PORTIONS OF THE TN BORDER DURING PEAK
HEATING. THE REST OF THE CWFA SHOULD REMAIN DRY WITH HIGH TEMPS
AROUND 90 DEGREES FOR THE LOWER ELEVATIONS AND LOW TO MID 80S FOR
THE HIGHER ELEVATIONS. AN AIR QUALITY ALERT IS IN AFFECT FROM 6AM
UNTIL 9PM TODAY FOR ELEVATED AMOUNTS OF GROUND LVL OZONE OVER THE
CLT AND HKY REGIONS.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
AS OF 300 AM WEDNESDAY...AS H5 SHORTWAVE MOVES OFFSHORE THU A
SHORTWAVE APPROACHES THE S APPALACHIANS FROM THE NW. BEST FORCING
STAYS WELL N OF THE AREA AND MID LVL RIDGE REMAINS OVER THE CWA.
MODEL SOUNDINGS REMAIN UNIMPRESSIVE...ESP ACROSS THE PIEDMONT...SO
LIMITED SCT CONVECTION TO THE N MTNS WITH ISOLD REST OF MTN RIDGES
AND PEAKS LATE THU AFTN INTO EARLY EVE. A WEAK UPPER WAVE AND ASSOC
COLD FRONT APPROACH THE AREA FROM THE NW FRI. THE GFS SHOWS THE MOST
RESPONSE WITH THE NAM AND ECMWF MORE RESERVED. BASED ON RECENT GFS
PESSIMISM USED A MODEL BLEND...LEANING MORE TOWARD THE NAM/ECMWF.
FCST SOUNDINGS STILL SHOW ENOUGH CAPE AND SHEAR FOR SOLID CHC POPS
ACROSS THE MTNS FRI AFTN...TAPERING TO LOW CHC ACROSS THE FOOTHILLS
AND SLIGHT CHC OVER THE SE CWA. TEMPS WILL BE ABOUT 5 DEG ABOVE AVG
THRU THE PD.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 310 AM WEDNESDAY...LATEST MODEL RUNS KEEP THE UPPER TROF OVER
THE E US THRU THE MIDDLE OF NEXT WEEK. MOISTURE ASSOC WITH
DISTURBANCE(S)IN THE GULF IS EXPECTED TO STAY S AND E OF THE CWA...
WHILE A WEAK SFC BOUNDARY MEANDERS OVER THE AREA THRU THE WEEKEND.
GFS AND ECMWF SHOW WEAK UPPER LVL DIVERGENCE OVER THE REGION SAT-SUN
BUT MOISTURE IS LIMITED. BASED ON THIS KEPT SLIGHT CHC POPS OVER THE
MTNS SAT AND ACROSS THE CWA SUN AS UPPER FORCING IMPROVES SLIGHTLY.
MODELS CONTINUE TO SHOW WEAK SFC BOUNDARY MOVG SE OF THE CWA MON-TUE
WITH LLVL CONVERGENCE AND INSTABILITY SETTING UP ALONG THE COAST...
WHILE THE W CAROLINAS AND NE GA STAY RELATIVELY DRY. TEMPS REMAIN
ABOVE AVG THRU THE FCST PD.
&&
.AVIATION /17Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...GENERALLY VFR CONDITIONS EXPECTED THRU THE PERIOD. THERE
IS A CHANCE FOR A BRIEF PERIOD OF MVFR FOG VSBY RESTRICTION IN THE
11Z-12Z TIMEFRAME.
ELSEWHERE...AT KAVL...A PERIOD OF LIFR STRATUS/FOG IS EXPECTED TO
REPEAT ITSELF IN THE 10Z-13Z TIMEFRAME...OTHERWISE VFR WITH WIDELY
SCATTERED -TSRA SCATTERED ACROSS THE NC MOUNTAINS TIL ABOUT 00Z.
ELSEWHERE...VFR CONDITIONS ARE EXPECTED EXCEPT FOR SOME AREAS OF
MVFR FOG RESTRICTIONS IN THE 11Z-13Z TIMEFRAME.
OUTLOOK...GENERALLY DRY/VFR CONDITIONS ARE EXPECTED EAST OF MTNS
THRU THURSDAY. EXPECT ISOLATED TO SCATTERED AFTERNOON TSTMS OVER THE
MTS...WITH VALLEY FOG POSSIBLE DURING THE MORNING. A WEAK COLD FRONT
APPROACHING THE AREA WILL INCREASE CHANCES FOR CONVECTION AT ALL TAF
SITES FRIDAY THROUGH AND SUNDAY AFTERNOONS.
AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...
WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...WINESETT
NEAR TERM...LG
SHORT TERM...RB
LONG TERM...RB
AVIATION...LG
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
240 PM CDT WED JUN 20 2012
.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT
240 PM CDT WED JUN 20 2012
FORECAST CONCERNS FOCUS ON THE STORMS THIS EVENING...POSSIBILITY FOR
SEVERE WEATHER.
CONVECTION HAS BUBBLED ALONG A NORTHEAST TO SOUTHWEST RUNNING COLD
FRONT...CURRENTLY RUNNING FROM NORTHWEST WI INTO NORTHWEST IA. GOOD
CONVERGENCE NEAR...BUT MOSTLY POST THE BOUNDARY...ALONG WITH A
STRONG THERMAL BAND IN THE LOW LAYERS. ABOUT 1000 OR SO J/KG OF
MLCAPE AROUND THE FRONT WITH EFFECTIVE SHEAR OF 40 TO 50 KTS. THERE
WILL BE A SEVERE RISK IN THE VICINITY OF THE FRONT INTO THE MID TO
POSSIBLY LATE EVENING HOURS. SOUNDINGS AND 0-3 KM SHEAR VECTORS
SUPPORT WIND AS THE MAIN THREAT...WITH SOME POTENTIAL FOR LARGE
HAIL. HEAVY RAIN PRODUCING FLOODING WILL ALSO BE POSSIBLE. MORE ON
THAT IN THE HYDRO DISCUSSION BELOW. THINK SHOWERS/STORMS WILL BECOME
MORE WIDESPREAD THIS EVENING BEHIND THE FRONT/CONVECTIVE LINE...IN
THE REGION OF SLOPING FRONTOGENETIC LIFT. CAPE MUCH LESS IN THIS
REGION...ALTHOUGH SHEAR WOULD BE A BIT BETTER. COULD BE SOME SEVERE
RISK IN THIS AREA...BUT THINK THE HIGHER THREAT WILL BE AROUND THE
FRONT.
FOR THU/FRI...THE REGION REMAINS UNDER CYCLONIC FLOW A LOFT...WITH
THE 20.12Z NAM AND GFS HINTING AT SOME WEAK RIPPLES IN THE FLOW
SPINNING ACROSS THE REGION THU AND FRI AFTERNOONS. FRIDAY SEEMS A
BIT STRONGER. STRONG LOW LEVEL LAPSE RATES WITH MUCAPES AROUND 500
J/KG IN THE AFTERNOON...MOSTLY NORTH/EAST OF THE I-94 CORRIDOR. NOT
A LOT...BUT ENOUGH LOW LEVEL MOISTURE INDICATED VIA RUC SOUNDINGS
AND RH PLOTS THAT SOME SHRA/TS COULD BE GENERATED IN THIS AREA. WILL
ADD SMALL CHANCES FOR THU AND CONTINUE THE FRI CHANCES.
THE LOW LEVEL JET/MOISTURE TRANSPORT WILL RESULT IN THUNDERSTORM
DEVELOPMENT ACROSS THE SD/NEB FRI NIGHT/SAT. THIS STORM COMPLEX AND
RESULTING MCV WILL SLIDE EAST ACROSS IA/MN/WI ON SAT...BRINGING A
SHOWER/STORM THREAT. THE NAM IS MORE AGGRESSIVE WITH A SOUTHERN
TRACK...WHICH WOULD SLIDE IT JUST SOUTH OF THE FORECAST AREA. THE
GFS AND GEM ARE FARTHER NORTH...WHILE THE EC LOOKS MORE LIKE A MIX
OF THE SOUTHERN/NORTHERN SOLUTIONS. WILL LEAN TOWARD CONSENSUS IN
THIS TIME FRAME.
THE PASSAGE OF THE COLD FRONT WILL USHER IN SOME LESS HUMID
AIR...WITH TEMPERATURES PRETTY CLOSE TO THE SEASONABLE NORMALS.
.LONG TERM...SUNDAY THROUGH WEDNESDAY
240 PM CDT WED JUN 20 2012
SOME DIFFERENCES IN THE MODELS WITH HOW LONG TO LINGER THE SAT
SYSTEM ACROSS THE REGION. THE EC WOULD BRING IT THROUGH SAT NIGHT
WHILE THE GFS WOULD HANG IT AROUND ON SUNDAY. GEM IS A BIT
QUICKER...ALA THE EC. WILL STEER TOWARD THE CONSENSUS SOLUTION IN
THIS PERIOD...WITH SOME LEAN ON THE QUICKER EC/GEM.
GFS AND ECMWF IN GOOD AGREEMENT WITH DROPPING A SFC HIGH ACROSS THE
UPPER MISSISSIPPI RIVER VALLEY FOR MON-WED WHILE AN UPPER LEVEL
RIDGE EASES SLOWLY EAST ACROSS THE PLAINS. THIS SHOULD RESULT IN A
DRY START TO THE NEW WORK WEEK...WITH TEMPERATURES NEAR TO BELOW
NORMAL. MOSTLY...HIGHS IN THE MID 70S TO AROUND 80 ARE EXPECTED.
&&
.AVIATION...THROUGH 18Z THURSDAY
1251 PM CDT WED JUN 20 2012
MAIN AVIATION CONCERN IS TIMING OF SHOWERS AND THUNDERSTORMS INTO
BOTH LSE AND RST TAF SITES FOR THIS AFTERNOON AND EVENING. THE
LATEST 20.12Z DETERMINISTIC MODELS SUGGEST REGION TO REMAIN CAPPED
THROUGH MID TO LATE THIS AFTERNOON OUT AHEAD OF COLD FRONT OVER
CENTRAL MINNESOTA. AS THE CAP WEAKENS LATE THIS AFTERNOON PER
20.15Z BUFKIT SOUNDINGS...EXPECT SHOWERS AND THUNDERSTORMS TO
DEVELOP ALONG AND BEHIND THE FRONT AND MOVE INTO THE TAF SITES
AFTER 20Z. IF THE CAP HOLDS....AS SOME HI RESOLUTION MODELS
SUGGEST...SHOWERS AND THUNDERSTORMS MAY NOT MOVE INTO THE RST AND
LSE TAF SITES UNTIL 23Z WEDNESDAY TO 00Z THURSDAY. AT THIS
TIME...HAVE KEPT TIMING OF SHOWERS AND THUNDERSTORMS AFTER 20Z AT
RST AND 22Z AT LSE. LATEST METARS INDICATE CEILINGS HEIGHTS IN THE
MVFR RANGE 2000-3000 FEET ALONG AND BEHIND COLD FRONT. THE 20.12Z
DETERMINISTIC MODELS SHOW CEILINGS LOWERING INTO THE MVFR RANGE
FOR A SHORT DURATION LATE THIS AFTERNOON AND INTO TONIGHT...AS
THE COLD FRONT MOVES ACROSS THE TAF SITES. HAVE INTRODUCED MVFR
CEILINGS AT RST AFTER 22Z AND AT LSE AFTER 00Z. VFR CONDITIONS
SHOULD PREVAIL AT BOTH TAF SITES AFTER 12Z THURSDAY.
&&
.HYDROLOGY...TONIGHT
240 PM CDT WED JUN 20 2012
PWS CLOSE TO 2 INCHES AND THE SLOW MOVEMENT OF A COLD FRONT SUGGEST
HEAVY RAIN WILL REMAIN A THREAT TONIGHT. WHILE THE INDIVIDUAL STORMS
SHOULD MOVE AT A DECENT CLIP NORTHEAST...THE SLOWER TRACK OF THE
FRONT COULD LEAD TO TRAINING OF STORMS WITH HEAVY RAIN. LOCALIZED 2
TO 3 INCHES WILL BE POSSIBLE...WITH OVERALL 1/2 TO 1 INCH TOTALS
MORE LIKELY.
SOME BASINS ARE STILL WET AND/OR HAVE RIVER LEVELS RUNNING HIGH...
INCLUDING THE ZUMBRO...BLACK...BUFFALO...TREMPEALEAU...AND
MISSISSIPPI. SO WILL HAVE TO KEEP AN EYE ON THINGS. LATEST RIVER
FORECASTS INDICATE THE MISSISSIPPI WILL RISE TO NEAR FLOOD STAGE
AGAIN AT WABASHA ON WED...WHICH MEANS OTHER SITES ALONG THE BIG
MUDDY WILL REACH HEIGHTS VERY SIMILAR TO WHAT WAS SEEN JUST LAST
WEEK.
CONTINUED THE HYDROLOGIC OUTLOOK /ESFARX/ TO HEIGHTEN THE PUBLIC
AWARENESS OF THE SITUATION.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
240 PM CDT WED JUN 20 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RIECK
LONG TERM....RIECK
AVIATION.....DTJ
HYDROLOGY....MW/RIECK
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
226 PM CDT WED JUN 20 2012
.SHORT TERM...TONIGHT AND THURSDAY.
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW SURFACE LOW
PRESSURE MOVING NORTHEAST OVER FAR NORTHWEST WISCONSIN...AND A COLD
FRONT TRAILING TO SOUTH-CENTRAL MINNESOTA EARLY THIS AFTERNOON.
SHOWERS AND STORMS ARE LIGHTING UP ALONG THE COLD FRONT AND SHOULD
CONTINUE TO DO SO AS THE ATMOSPHERE DESTABILIZES WITH FURTHER
HEATING...BUT NOTHING ORGANIZED AT THE MOMENT. RIGHT REAR QUAD OF
AN UPPER JET STREAK AND FGEN ARE ALSO SPREADING OVER THE FRONT TO
AID IN THE LARGE-SCALE ASCENT. BEHIND THE FRONT...SHOWERS AND
ISOLATED STORMS ARE ALSO DEVELOPING OVER NORTH DAKOTA BENEATH AN
UPPER TROUGH. AS THE FRONT SLOWLY MOVES EAST TONIGHT...SEVERE
WEATHER IS THE MAIN FORECAST CONCERN.
TONIGHT...THE UPPER TROUGH OVER THE NORTHERN PLAINS WILL PUSH A COLD
FRONT ACROSS CENTRAL AND NORTH-CENTRAL WISCONSIN THIS EVENING...AND
EAST-CENTRAL AND NORTHEAST WISCONSIN AFTER MIDNIGHT. EXPECT STRONG STORMS
TO DEVELOP AHEAD OF THE FRONT THIS AFTERNOON WHERE ML CAPES WILL BE
IN THE 1500-2000 J/KG RANGE OVER CENTRAL AND NORTHERN WISCONSIN.
WITH A DECENT WIND FIELD AND EFFECTIVE SHEARS BETWEEN
30-35KTS...DAMAGING WINDS AND LARGE HAIL WILL BE THE PRIMARY THREATS
IN THE THUNDERSTORMS AT LEAST INITIALLY OVER CENTRAL AND
NORTH-CENTRAL WISCONSIN AS THE STORMS ARRIVE. INSTABILITY DOES
DIMINISH FAIRLY QUICKLY THIS EVENING...SO EXPECT STORMS TO WEAKEN AS
THEY MOVE EAST...PERHAPS TO AN ISOLATED SEVERE THREAT AS THEY ENTER
THE FOX VALLEY AROUND MIDNIGHT. PWATS OF 1.80 INCHES AHEAD OF THE
FRONT SHOULD ALLOW THE STORMS TO PRODUCE DECENT RAINFALL. SHOULD
SEE THE STORMS MOVE OUT AFTER 09Z AND PARTIAL CLEARING TO MOVE IN IN
ITS WAKE. LOWS IN THE MID 50S NORTH TO MID 60S SOUTH.
THURSDAY...THE COLD FRONT WILL HAVE EXITED THE REGION BY 12Z
THURSDAY AND COOLER AND DRIER AIR WILL HAVE FILTERED ACROSS THE
AREA. THE UPPER TROUGH WILL SETTLE OVERHEAD THROUGH THE DAY AND
PROGGED SOUNDINGS INDICATE LOW LEVEL INSTABILITY DEVELOPING WITH
DAYTIME HEATING. DEFINITELY GOOD ENOUGH FOR A SUBSTANTIAL CU FIELD
ESPECIALLY AFTER ALL THE RAINFALL LATELY. NOT SURE ABOUT A TRIGGER
FOR SHOWER POSSIBILITIES...BUT THE 12Z NAM DOES INDICATE AN EMBEDDED
SHORTWAVE SWINGING ACROSS THE AREA IN THE AFTERNOON THAT COULD
INTERACT WITH 300-400 J/KG OF ML CAPE OVER N-C WISCONSIN. WILL
LEAVE THE AREA DRY FOR NOW BUT MENTION POSSIBILITY TO THE NEXT SHIFT.
HIGHS IN THE MID 70S NORTH TO LOW 80S SOUTH.
.LONG TERM...THURSDAY NIGHT THROUGH NEXT WEDNESDAY. A NICE
SEASONABLE PERIOD OF WEATHER EXPECTED WITH NORTHWEST UPPER FLOW
AND A REFRESHING HUDSON BAY HIGH DROPPING SOUTH INTO THE GREAT
LAKES EARLY NEXT WEEK.
A JET STREAK MOVING THROUGH THE UPPER FLOW SHOULD COMBINE WITH
COLD AIR ALOFT TO PRODUCE SOME SHOWERS AND THUNDERSTORMS FRIDAY
ESPECIALLY IN THE NORTHEAST. ANOTHER CHANCE OF SHOWERS AND
THUNDERSTORMS SATURDAY AND SATURDAY NIGHT AS MORE JET ENERGY MOVES
THROUGH AND A REINFORCING COLD FRONT MOVES IN FROM THE NORTH.
BIG SURFACE HIGH THEN SHOULD DROP SOUTH INTO THE GREAT LAKES AND
BRING DRY AND COOL WEATHER FOR A GOOD PART OF NEXT WEEK. GFS
SUGGESTS THAT THE AIR MAY BE DRY ENOUGH FOR A LATE SEASON FROST IN
THE FAR NORTH TUESDAY NIGHT. WILL NOT MENTION YET IN THE HAZARDOUS
WEATHER OUTLOOK YET DUE TO MODEL DIFFERENCES.
&&
.AVIATION...A COLD FRONT WILL SLOWLY MOVE ACROSS CENTRAL AND EASTERN
WISCONSIN LATE THIS AFTERNOON THROUGH LATE TONIGHT. SHOWERS AND
STORMS WILL PUSH ACROSS THE REGION AHEAD OF THIS FRONT. SOME STORMS
MAY BECOME STRONG TO SEVERE OVER CENTRAL AND NORTH-CENTRAL WISCONSIN
LATE THIS AFTERNOON INTO EARLY THIS EVENING. CIGS AND VSBYS WILL
LIKELY FALL TO MVFR IF NOT IFR IN ANY THUNDERSTORMS. IMPROVING
CONDITIONS WILL BE FOUND BEHIND THE FRONT LATE TONIGHT INTO
TOMORROW. LOOKING AT A FAIRLY WIDESPREAD DIURNAL CU FIELD TO
DEVELOP BY LATE MORNING WHICH COULD LEAD TO HIGH END MVFR CIGS AT
RHI FOR A FEW HOURS.
MPC
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MPC/RDM
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1238 PM CDT WED JUN 20 2012
UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE
.PREV DISCUSSION...ISSUED AT 1043 AM CDT WED JUN 20 2012...
.UPDATE...LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LOW
PRESSURE AND ASSOCIATED COLD FRONT NOW MOVING INTO NORTHWEST
WISCONSIN THIS MORNING. CONVECTION AHEAD OF THE FRONT AND IN THE
RIGHT REAR QUAD OF JET STREAK WILL STAY NORTHWEST OF THE FORECAST
ARE THIS MORNING. BUT DO LOOK FOR THUNDERSTORMS TO REDEVELOP ALONG
THE FRONT LATER THIS AFTERNOON. THE SPC WRF AND OTHER GUIDANCE
POINT TOWARDS CONVECTION MOVING INTO N-C WISCONSIN AFTER 21Z AND
INTO NORTHEAST WISCONSIN AFTER 03Z. PROGGED NAM SOUNDINGS SHOW
1500-2000 J/KG OF ML CAPE AND 30-35 KTS OF EFFECTIVE SHEAR AHEAD
OF THE BOUNDARY THIS AFTERNOON. THE MAIN THREAT WILL CONTINUE TO
BE STRONG GUSTY WINDS BUT DO NOT THINK CAN RULE OUT LARGE HAIL
DURING THE PEAK HEATING PERIOD UNTIL INSTABILITY RAPIDLY
DIMINISHES IN THE EVENING. NORTHEAST WISCONSIN SHOULD BE
RELATIVELY SAFER FROM SEVERE WEATHER AS THEY ARRIVE LATE IN THE EVENING.
MPC
&&
.PREV DISCUSSION...ISSUED AT 645 AM CDT WED JUN 20 2012...
SHORT TERM...TODAY THROUGH THURSDAY...MAIN FCST CONCERNS INCLUDE
PCPN TIMING...AND THE THREAT OF SVR TSTMS AND HEAVY RAINFALL THIS
AFTERNOON AND EVENING.
MSAS ANALYSIS SHOWED A SFC LOW IN SW MN...WITH A COLD FRONT EXTENDING
SWWD INTO THE CENTRAL PLAINS...AND A WARM FRONT EXTENDING NEWD
INTO FAR NW WI AND THE UPPER PENINSULA. A LARGE AREA OF SHRA/TSRA
WAS ONGOING NW OF THE COLD FRONT AND NORTH OF THE WARM FRONT...
WITH TRAINING LEADING TO HEAVY RAINFALL AND SOME FLOODING FROM
EASTERN SD INTO THE MN ARROWHEAD. CLEAR TO PARTLY CLOUDY SKIES
COVERED GRB CWA...BUT DEVELOPING CONVECTION WAS EDGING TOWARD OUR
FAR NW COUNTIES EARLY THIS MORNING.
ALTHOUGH CURRENT CONVECTION MAY BRUSH PARTS OF NC WI THIS MORNING...
MODELS CONTINUE TO SUGGEST THAT THE MAIN BRUNT OF THE PCPN WILL
OCCUR ALONG AND BEHIND THE COLD FRONT AS IT MOVES INTO GRB CWA
LATER THIS AFTERNOON AND EVENING. MODIFIED FCST SOUNDINGS WOULD
INDICATE THAT SFC BASED CONVECTION COULD DEVELOP ALONG THE COLD
FRONT OVER PARTS OF NC/C WI LATER THIS AFTERNOON...AS MID-LEVEL
CAA ERODES THE CAP AND SBCAPE INCREASES TO AROUND 2000 J/KG. STRONG
UNIDIRECTIONAL SW WINDS AND WINDEX VALUES AROUND 55 KTS SUGGEST
THAT DAMAGING WINDS ARE A GOOD BET IF SFC BASED CONVECTION CAN
DEVELOP. NOT QUITE CONFIDENT ENOUGH TO EXPLICITLY MENTION SEVERE
WORDING IN THE GRIDS/FCST...BUT WILL CERTAINLY HIGHLIGHT THE
POTENTIAL IN THE HWO. CONFIDENCE IS HIGHER IN THE THREAT OF HVY
RAINFALL...AS PW`S INCREASE TO NEAR 2 INCHES AND H8 DEW POINTS
RISE TO AROUND 16 C IN THE VCNTY OF THE COLD FRONT. THE COMBINATION
OF LLVL CONVERGENCE ALONG THE BOUNDAY AND INCREASING UPPER LEVEL
DIVG IN THE RRQ OF A STG UPPER LEVEL JET ARE ALSO SUPPORTIVE OF
A HEAVY RAINFALL THREAT...SO WILL MENTION IN THE FCST. WILL HAVE
LIKELY POPS IN THE FAR NW COUNTIES THIS AFTERNOON...THEN SPREAD
THEM ACROSS THE REST OF THE CWA TONIGHT. A VERY WARM START TO THE
DAY COMBINED WITH MIXING THROUGH 825-800 MB SUPPORTS HIGHS IN THE
80S TO LOWER 90S TODAY. THE DEEP MIXING WILL ALSO LEAD TO WINDS
GUSTING OVER 30 MPH AT TIMES THIS AFTERNOON AND EARLY EVG.
THE FRONT WILL SHIFT EAST OF THE RGN BY THURSDAY MORNING...WITH
COOLER AND DRIER AIR ARRIVING. WILL CONTINUE WITH THE PREVIOUS
DRY FCST...AND MAX TEMPS THAT ARE 10-15 DEGREES COOLER THAN
TODAY.
LONG TERM...THURSDAY NIGHT THROUGH TUESDAY.
MODELS HAD A MID LEVEL TROUGH PASSING EAST OF WISCONSIN AT THE
START OF THE FORECAST PERIOD. A 500MB LOW WAS THEN FORECAST TO
DEVELOP EAST OF THE STATE AS A CENTRAL CONUS RIDGE BUILDS. THIS
WILL KEEP THE FORECAST AREA IN NORTHWEST FLOW ALOFT THROUGH EARLY
NEXT WEEK. THIS SHOULD BRING A PERIOD OF MOSTLY DRY WEATHER
WITH TEMPERATURES NEAR NORMAL FOR THIS TIME OF YEAR.
HAVE SLIGHT CHANCE POPS FOR THURSDAY NIGHT INTO FRIDAY AS 00Z
GFS/00Z NAM/12Z ECMWF ALL HAD SOME QPF DURING ONE OR BOTH OF THOSE
PERIODS AND CYCLONIC FLOW PERSISTS AT BOTH THE SURFACE AND ALOFT.
SHORT WAVE ENERGY COMBINED WITH THE RIGHT ENTRANCE REGION OF AN
UPPER LEVEL JET AND AN APPROACHING SURFACE SYSTEM WILL BRING A
CHANCE OF SHOWERS AND THUNDERSTORMS TO THE AREA FRIDAY NIGHT
THROUGH SATURDAY NIGHT IN THE WEST AND SATURDAY THROUGH SUNDAY IN
THE EAST. HIGH PRESSURE THEN MOVES INTO THE REGION AS THE UPPER
RIDGE CONTINUES TO BUILD TO THE WEST. AS A RESULT...HAVE GONE WITH
A DRY FORECAST FOR THE REST OF THE PERIOD.
&&
.AVIATION...A COLD FRONT WILL SLOWLY MOVE ACROSS CENTRAL AND EASTERN
WISCONSIN LATE THIS AFTERNOON THROUGH LATE TONIGHT. SHOWERS AND
STORMS WILL PUSH ACROSS THE REGION AHEAD OF THIS FRONT. SOME STORMS
MAY BECOME STRONG TO SEVERE OVER CENTRAL AND NORTH-CENTRAL WISCONSIN
LATE THIS AFTERNOON INTO EARLY THIS EVENING. CIGS AND VSBYS WILL
LIKELY FALL TO MVFR IF NOT IFR IN ANY THUNDERSTORMS. IMPROVING
CONDITIONS WILL BE FOUND BEHIND THE FRONT LATE TONIGHT INTO
TOMORROW. LOOKING AT A FAIRLY WIDESPREAD DIURNAL CU FIELD TO
DEVELOP BY LATE MORNING WHICH COULD LEAD TO HIGH END MVFR CIGS AT
RHI FOR A FEW HOURS.
MPC
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$