Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/13/12
AREA FORECAST DISCUSSION
NWS ALBANY NY
158 PM EDT MON JUN 11 2012
.SYNOPSIS...
HIGH PRESSURE ALOFT WILL BUILD INTO THE REGION THROUGH TODAY...WITH
WARM AND SOMEWHAT HUMID CONDITIONS THROUGH TONIGHT. AN ISOLATED
AFTERNOON SHOWER OR THUNDERSTORM WILL BE POSSIBLE ACROSS PORTIONS
OF THE WESTERN MOHAWK VALLEY AND ADIRONDACKS. WIDESPREAD SHOWERS
AND THUNDERSTORMS WILL RETURN FOR TUESDAY INTO EARLY WEDNESDAY...
ASSOCIATED WITH A PERIOD OF MODERATE TO HEAVY RAINFALL AS A FRONTAL
BOUNDARY SLOWLY CROSSES THE REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 PM...ISOLATED CONVECTION HAS DEVELOPED OVER THE
ADIRONDACK ZONES SO WILL LEAVE THE SLIGHT CHANCE POPS IN THAT AREA
AND THE MOHAWK VALLEY AS WELL. HAVE LEFT HIGH TEMP FORECAST FOR
TODAY AS IS...OR RAISED BY A FEW DEGREES...ESPECIALLY ACROSS THE
NORTHWEST PART OF THE FORECSAT AREA.
****PREVIOUS DISCUSSION****
AS OF 935 AM EDT...STRATUS CLOUDS CONTINUE TO EXPAND N AND
W...ACROSS NW CT...THE MID HUDSON VALLEY REGION AND
BERKSHIRES...AS WELL AS ACROSS THE SE CATSKILLS. AREAS OF LOW
CLOUDS/FOG ACROSS THE WESTERN ADIRONDACKS...AND PORTIONS OF THE
HELDERBERGS APPEARS TO BE DECREASING.
HAVE MADE SOME CHANGES TO GRIDDED DATABASE BASED ON RECENT
OBS...12Z UA SOUNDINGS...AND LATEST RAP/HRRR. FIRST WAS TO EXPAND THE
SLIGHT CHC POPS A BIT FURTHER SOUTH INTO THE CENTRAL AND WESTERN
MOHAWK VALLEY. THE LATEST RAP AND HRRR CONTINUE TO INDICATE
POCKETS OF FAIRLY DECENT INSTABILITY DEVELOPING THIS AFTERNOON IN
THIS REGION. IN ADDITION...THIS REGION WILL BE CLOSER TO A WEAK
BOUNDARY...SEPARATING A SLIGHTLY COOLER MODIFIED MARINE AIR MASS
TO THE E AND S...FROM A WARMER...MORE CONTINENTAL AIR MASS TO THE
N AND W.
ELSEWHERE...HAVE INCREASED CLOUDS COVERAGE AND LOWERED MAX TEMPS
ACROSS WESTERN NEW ENGLAND...AND THE MID HUDSON VALLEY REGION. AS
THE AFOREMENTIONED MODIFIED MARINE AIR CONTINUES TO WORK N AND
W...MAX TEMPS MAY FAIL TO REACH 80 ACROSS THE BERKSHIRES/SOUTHERN
GREENS...LITCHFIELD CO AND THE MID HUDSON VALLEY.
ELSEWHERE...STILL EXPECT MAXES TO REACH 80-85 ACROSS THE UPPER
HUDSON VALLEY FROM ALBANY NORTH...AND MID 80S ACROSS THE CENTRAL
AND WESTERN MOHAWK VALLEY...WHERE EVEN SOME UPPER 80S ARE
POSSIBLE.
WILL NEED TO WATCH HOW FAR N AND W THE LOWER CLOUDS REACH...AS
THIS MAY REQUIRE ADDITIONAL MODIFICATIONS TO MAX TEMPS/TOWARD
LOWER VALUES/WITHIN THE CAPITAL REGION SHOULD MORE CLOUDS FORM.
FOR TONIGHT...ANY CONVECTION SHOULD QUICKLY DISSIPATE THIS EVENING
AS THE UPPER LEVEL RIDGE AXIS SLIDES FURTHER OFFSHORE. THIS WILL
ALLOW THE UPSTREAM NORTHERN PLAINS TROUGH TO MIGRATE FURTHER EAST
TOWARD THE CENTRAL GREAT LAKES REGION. ALONG WITH ITS
APPROACH...MOISTURE ADVECTION FROM THE SOUTHEAST CONUS AND OHIO
VALLEY WILL ADVANCE NORTHWARD. FORECAST SOUNDINGS SUPPORT AN
ENTRAINMENT OF LOW LEVEL STRATUS FROM THE ATLANTIC YET RATHER DRY
BETWEEN 850-500MB TO KEEP THE CHANCE OF PRECIP WEST OF THE REGION.
EXPECTATIONS ARE FOR AN INCREASING CLOUD COVER AND A MILD
OVERNIGHT WITH LOWS MAINLY INTO THE 60S.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
RAINFALL POTENTIAL INCREASES FROM WEST TO EAST AS THE LOW LEVEL
JET INCREASES TO >40KTS TO ASSIST WITH RAPID MOISTURE TRANSPORT
INTO THE CWFA. NCEP MODEL SUITE ARE IN EXCELLENT AGREEMENT WITH A
PERIOD OF MODERATE RAINFALL TO MOVE ACROSS THE REGION ON TUESDAY.
INSTABILITY PARAMETERS ARE NOT FAVORABLE FOR SEVERE
WEATHER...HOWEVER...MID LEVEL VALUES PER THE SHOWALTERS STILL
SUPPORT EMBEDDED DEEPER CONVECTION. PWATS ARE PROGGED TO CLIMB IN
EXCESS OF 1.75" WITH UPSTREAM VALUES CLOSE TO 2.00". THESE VALUES
ARE 2-3 STANDARD DEVIATIONS ABOVE NORMAL TO SUPPORT EMBEDDED
PERIODS OF HEAVY RAINFALL. FAVORED UPSLOPE REGIONS OF THE
CATSKILLS...NW CT INTO THE BERKS AND SOUTHERN VT MAY ENHANCE
RAINFALL RATES. SEE THE HYDRO DISCUSSION FOR FURTHER DETAILS ON
THE RAINFALL POTENTIAL IMPACTS. OTHERWISE...RATHER HIGH POPS
EXPECTED DURING THE DAY WITH TEMPERATURES A BIT COOLER DUE TO THE
MARINE INFLUENCE...CLOUDS AND PRECIP WITH HIGHS MAINLY IN THE MID
60S TO LOWER 70S.
MODELS HAVE COME AROUND TO THE ECMWF OF THE PAST SEVERAL DAYS
WITH A MORE PROGRESSIVE FROPA TUESDAY EVENING. SO WE WILL
GRADUALLY LOWER POPS FROM WEST TO EAST ALONG WITH IMPROVEMENTS TO
THE SKY COVER. HOWEVER...EAST OF THE HUDSON RIVER...THOSE CLOUDS
WILL LIKELY LINGER LONGER UNTIL THE FRONT HAS CLEARED THE EASTERN
SEABOARD.
CONFIDENCE CONTINUES TO INCREASE THAT WEDNESDAY SHOULD TURN OUT TO
BE A DRIER DAY. WHILE THE MID LEVELS OF THE ATMOSPHERE ARE
EXPECTED TO REMAIN RATHER DRY...LOWER LEVELS WILL LIKELY REMAIN A
BIT MORE MOIST DUE TO THE RAINFALL FROM TUESDAY EVENT AND LOW
LEVEL NORTHEAST WIND TRAJECTORIES. SCT-BKN CLOUDS ARE EXPECTED FOR
OUT ADJACENT WESTERN NEW ENGLAND COUNTIES WITH DOWNSLOPING
COMPONENT INTO THE HUDSON RIVER VALLEY FOR AT LEAST A PTSUNNY DAY.
AS FOR TEMPERATURES...A MODEL BLEND APPROACH WAS UTILIZED WHICH
DOWNPLAYS THE COOLER VALUES WITHIN THE GFS MOS AND THE MUCH WARMER
VALUES SEEN IN THE MET MOS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
THE MODELS HAVE STARTED TO COME INTO BETTER AGREEMENT REGARDING THE
EXTENDED PERIOD...FOR THE PERIOD BEGINNING ON WEDNESDAY EVENING. AT
THIS POINT...IT APPEARS THAT THE UPPER TROUGH RESPONSIBLE FOR
BRINGING THE MID WEEK WET WEATHER WILL BE PROGRESSIVE AND CONTINUE
TO MOVE EASTWARD ACROSS CANADA. ALTHOUGH THE SURFACE FRONTAL
BOUNDARY WON/T MAKE A CLEAN SWEEP OUT TO SEA...IT LOOKS TO GENERALLY
WASH OUT ACROSS NEW ENGLAND TO THE EAST OF OUR REGION. ALSO...WHILE
IT STILL APPEARS THAT A SURFACE WAVE MAY DEVELOP ALONG THIS
FRONT...THE LATEST 00 UTC ECMWF/GFS BOTH SHOW A WEAK LOW REMAINING
OFF THE COAST...WITH HIGH PRESSURE BUILDING INTO OUR AREA FROM
SOUTHERN CANADA. WHILE WE STILL MAY HAVE A LOW CHC/SLIGHT CHC FOR A
RAIN SHOWER ACROSS THE REGION /ESP FOR EASTERN AREAS/ FOR WED NIGHT
INTO THURSDAY DUE TO THE PROXIMITY OF THE SFC BOUNDARY...IT DOESN/T
APPEAR TO BE A WASHOUT BY ANY STRETCH. SKIES LOOK TO RANGE FROM
PARTLY CLOUDY IN WESTERN AREAS...TO MOSTLY CLOUDY FOR WESTERN NEW
ENGLAND...DUE TO THE WEAK NE SURFACE FLOW IN PLACE. MIN TEMPS LOOK
TO RANGE FROM THE MID 40S TO UPPER 50S FOR WED NIGHT...WITH MAX
TEMPS GENERALLY IN THE 70S ON THURSDAY.
STRONG UPPER RIDGING LOOKS TO BUILD INTO THE REGION FOR FRIDAY INTO
THE WEEKEND AS A RIDGE OVER THE GREAT LAKES BENDS NORTHEASTWARD INTO
OUR AREA. ALTHOUGH THE MODELS SHOW A CLOSED OFF 500 HPA LOW ACROSS
THE WESTERN ATLANTIC...IT LOOKS TO STAY FAR ENOUGH EAST OF OUR AREA
TO BE OF ANY CONCERN FOR US. WITH THE BUILDING RIDGE...AND WARMING
TEMPS ALOFT...ENOUGH OF A CAP LOOKS TO BE IN PLACE TO PREVENT ANY
CONVECTION FROM FIRING UP...SO HAVE GONE WITH A DRY FORECAST FOR
FRIDAY ONWARD. VALLEY MAX TEMPS SHOULD BE GRADUALLY WARMER AND
WARMER EACH DAY...WITH UPPER 70S TO NEAR 80 FOR FRIDAY...LOW 80S FOR
SATURDAY...AND LOW TO MID 80S FOR SUNDAY. SKIES GENERALLY LOOK
MOSTLY CLEAR TO PARTLY CLOUDY. AT THIS POINT...DEWPOINTS DON/T LOOK
TOO MUGGY JUST YET...WITH TDS GENERALLY IN THE 50S F.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
HIGH PRESSURE WILL REMAIN ANCHORED OFF THE NEW ENGLAND COAST
THROUGH TONIGHT. A WARM FRONT APPROACHING FROM THE SOUTHWEST WILL
SPREAD CLOUDS...AND SHOWERS INTO THE REGION FOR TUESDAY AFTERNOON
AND NIGHT.
EXPECT VFR CONDITIONS THROUGH AT LEAST EARLY TONIGHT. THEN...AS A
MOIST S/SE FLOW CONTINUES...SOME LOW CLOUDS ARE EXPECTED TO
DEVELOP AND SPREAD NORTHWARD AFTER 06Z/TUE. THIS SHOULD LEAD TO
MVFR CIGS DEVELOPING PRIOR TO 12Z/TUE...WITH A CHANCE FOR IFR CIGS
AT KPSF...AND POSSIBLY KPOU. THERE IS A SLIGHT CHANCE THAT IFR
CIGS MAY SPREAD EVEN FURTHER N...BUT AT THIS TIME...CONFIDENCE NOT
QUITE HIGH ENOUGH TO INCLUDE AT KALB/KGFL.
AREAS OF MVFR CIGS WILL LINGER THROUGH 14Z-15Z/TUE...WITH SOME
POSSIBILITY OF IMPROVEMENT INTO THE LOW VFR RANGE THEREAFTER.
HOWEVER...SHOWERS SHOULD DEVELOP ACROSS WESTERN AND CENTRAL NYS
DURING THE MORNING...AND MAY IMPACT TAF SITES WEST OF THE HUDSON
RIVER AFTER 16Z/TUE.
SOUTH TO SOUTHEAST WINDS WILL REMAIN AT 8-12 KT THIS
AFTERNOON...WITH SOME GUSTS OF 20-25 KT POSSIBLE...ESP AT KALB DUE
TO FUNNELING EFFECTS UP THE HUDSON RIVER VALLEY. SOUTH TO
SOUTHEAST WINDS WILL DIMINISH TO 5-10 KT TONIGHT...THEN INCREASE
AGAIN TO 8-12 KT TUE MORNING...WITH SOME GUSTS OF 20-25 KT POSSIBLE.
OUTLOOK...
TUE-TUE NT...VFR/MVFR. CHC IFR. AFTERNOON SHRA/TSRA LIKELY.
WED...VFR/MVFR. SHRA POSSIBLE EARLY.
THU/SAT...VFR. SLIGHT CHC -SHRA. CHC LATE NIGHT/EARLY MORNING
MVFR/IFR IN FOG/STRATUS.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS ARE EXPECTED OVER THE NEXT SEVERAL DAYS.
A SOUTH TO SOUTHEAST WIND WILL INCREASE TO AROUND 10 MPH TODAY WITH
DRY WEATHER EXPECTED. AFTERNOON RH VALUES WILL DROP INTO THE 35-50
PERCENT...HIGHEST TO THE WEST OF ALBANY. MINIMUM RH VALUES TONIGHT
REBOUND TO GREATER THAN 80 PERCENT.
A WETTING RAIN IS EXPECTED ON TUESDAY TO FURTHER REDUCE FIRE
WEATHER CONCERNS.
&&
.HYDROLOGY...
A MODERATE RAINFALL EVENT IS EXPECTED ON TUESDAY ACROSS THE HYDRO
SERVICE AREA. LATEST MODEL GUIDANCE SUPPORTS A ROBUST MOISTURE
TRANSPORT THAT SHOULD GENERATE AT LEAST BROKEN COVERAGE OF
MODERATE TO HEAVY EMBEDDED CONVECTIVE RAINFALL RATES. EXPECTING
THE RAINFALL TO BE OROGRAPHICALLY ENHANCED ACROSS PORTIONS OF THE
CATSKILLS....BERKSHIRES AND SOUTHERN GREENS. PWAT ANOMALIES OF 2
TO 3 STD DEV ABOVE NORMAL...A >40 KT SOUTHERLY LOW LEVEL JET
HELPING TO ENHANCE ISENTROPIC LIFT AND OROGRAPHICS SHOULD HELP
ENHANCE RAINFALL RATES...AND THUS EXPECTING SOME LOCALLY HEAVIER
TOTALS FOR THE EVENT AT OR ABOVE 2 INCHES.
THIS SHOULD PRODUCE RISES ON AREA RIVERS AND STREAMS...BUT NO
FLOODING IS EXPECTED ON THE STREAMS AND RIVERS. LATEST RUN OF THE
MMEFS GUIDANCE ALSO SUPPORT THIS IDEA WITH NO POINTS EXPECTED TO
CLIMB ABOVE FLOOD STAGE.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...GJM/KL/BGM
NEAR TERM...GJM/KL/BGM
SHORT TERM...BGM
LONG TERM...FRUGIS
AVIATION...KL
FIRE WEATHER...BGM
HYDROLOGY...BGM
AREA FORECAST DISCUSSION
NWS ALBANY NY
142 PM EDT MON JUN 11 2012
.SYNOPSIS...
HIGH PRESSURE ALOFT WILL BUILD INTO THE REGION THROUGH
TODAY...WITH WARM AND SOMEWHAT HUMID CONDITIONS THROUGH TONIGHT.
WIDESPREAD SHOWERS AND THUNDERSTORMS WILL RETURN FOR TUESDAY INTO
EARLY WEDNESDAY ASSOCIATED WITH A PERIOD OF MODERATE TO HEAVY
RAINFALL AS A FRONTAL BOUNDARY SLOWLY CROSSES THE REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 935 AM EDT...STRATUS CLOUDS CONTINUE TO EXPAND N AND
W...ACROSS NW CT...THE MID HUDSON VALLEY REGION AND
BERKSHIRES...AS WELL AS ACROSS THE SE CATSKILLS. AREAS OF LOW
CLOUDS/FOG ACROSS THE WESTERN ADIRONDACKS...AND PORTIONS OF THE
HELDERBERGS APPEARS TO BE DECREASING.
HAVE MADE SOME CHANGES TO GRIDDED DATABASE BASED ON RECENT
OBS...12Z UA SOUNDINGS...AND LATEST RAP/HRRR. FIRST WAS TO EXPAND THE
SLIGHT CHC POPS A BIT FURTHER SOUTH INTO THE CENTRAL AND WESTERN
MOHAWK VALLEY. THE LATEST RAP AND HRRR CONTINUE TO INDICATE
POCKETS OF FAIRLY DECENT INSTABILITY DEVELOPING THIS AFTERNOON IN
THIS REGION. IN ADDITION...THIS REGION WILL BE CLOSER TO A WEAK
BOUNDARY...SEPARATING A SLIGHTLY COOLER MODIFIED MARINE AIR MASS
TO THE E AND S...FROM A WARMER...MORE CONTINENTAL AIR MASS TO THE
N AND W.
ELSEWHERE...HAVE INCREASED CLOUDS COVERAGE AND LOWERED MAX TEMPS
ACROSS WESTERN NEW ENGLAND...AND THE MID HUDSON VALLEY REGION. AS
THE AFOREMENTIONED MODIFIED MARINE AIR CONTINUES TO WORK N AND
W...MAX TEMPS MAY FAIL TO REACH 80 ACROSS THE BERKSHIRES/SOUTHERN
GREENS...LITCHFIELD CO AND THE MID HUDSON VALLEY.
ELSEWHERE...STILL EXPECT MAXES TO REACH 80-85 ACROSS THE UPPER
HUDSON VALLEY FROM ALBANY NORTH...AND MID 80S ACROSS THE CENTRAL
AND WESTERN MOHAWK VALLEY...WHERE EVEN SOME UPPER 80S ARE
POSSIBLE.
WILL NEED TO WATCH HOW FAR N AND W THE LOWER CLOUDS REACH...AS
THIS MAY REQUIRE ADDITIONAL MODIFICATIONS TO MAX TEMPS/TOWARD
LOWER VALUES/WITHIN THE CAPITAL REGION SHOULD MORE CLOUDS FORM.
FOR TONIGHT...ANY CONVECTION SHOULD QUICKLY DISSIPATE THIS EVENING
AS THE UPPER LEVEL RIDGE AXIS SLIDES FURTHER OFFSHORE. THIS WILL
ALLOW THE UPSTREAM NORTHERN PLAINS TROUGH TO MIGRATE FURTHER EAST
TOWARD THE CENTRAL GREAT LAKES REGION. ALONG WITH ITS
APPROACH...MOISTURE ADVECTION FROM THE SOUTHEAST CONUS AND OHIO
VALLEY WILL ADVANCE NORTHWARD. FORECAST SOUNDINGS SUPPORT AN
ENTRAINMENT OF LOW LEVEL STRATUS FROM THE ATLANTIC YET RATHER DRY
BETWEEN 850-500MB TO KEEP THE CHANCE OF PRECIP WEST OF THE REGION.
EXPECTATIONS ARE FOR AN INCREASING CLOUD COVER AND A MILD
OVERNIGHT WITH LOWS MAINLY INTO THE 60S.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
RAINFALL POTENTIAL INCREASES FROM WEST TO EAST AS THE LOW LEVEL
JET INCREASES TO >40KTS TO ASSIST WITH RAPID MOISTURE TRANSPORT
INTO THE CWFA. NCEP MODEL SUITE ARE IN EXCELLENT AGREEMENT WITH A
PERIOD OF MODERATE RAINFALL TO MOVE ACROSS THE REGION ON TUESDAY.
INSTABILITY PARAMETERS ARE NOT FAVORABLE FOR SEVERE
WEATHER...HOWEVER...MID LEVEL VALUES PER THE SHOWALTERS STILL
SUPPORT EMBEDDED DEEPER CONVECTION. PWATS ARE PROGGED TO CLIMB IN
EXCESS OF 1.75" WITH UPSTREAM VALUES CLOSE TO 2.00". THESE VALUES
ARE 2-3 STANDARD DEVIATIONS ABOVE NORMAL TO SUPPORT EMBEDDED
PERIODS OF HEAVY RAINFALL. FAVORED UPSLOPE REGIONS OF THE
CATSKILLS...NW CT INTO THE BERKS AND SOUTHERN VT MAY ENHANCE
RAINFALL RATES. SEE THE HYDRO DISCUSSION FOR FURTHER DETAILS ON
THE RAINFALL POTENTIAL IMPACTS. OTHERWISE...RATHER HIGH POPS
EXPECTED DURING THE DAY WITH TEMPERATURES A BIT COOLER DUE TO THE
MARINE INFLUENCE...CLOUDS AND PRECIP WITH HIGHS MAINLY IN THE MID
60S TO LOWER 70S.
MODELS HAVE COME AROUND TO THE ECMWF OF THE PAST SEVERAL DAYS
WITH A MORE PROGRESSIVE FROPA TUESDAY EVENING. SO WE WILL
GRADUALLY LOWER POPS FROM WEST TO EAST ALONG WITH IMPROVEMENTS TO
THE SKY COVER. HOWEVER...EAST OF THE HUDSON RIVER...THOSE CLOUDS
WILL LIKELY LINGER LONGER UNTIL THE FRONT HAS CLEARED THE EASTERN
SEABOARD.
CONFIDENCE CONTINUES TO INCREASE THAT WEDNESDAY SHOULD TURN OUT TO
BE A DRIER DAY. WHILE THE MID LEVELS OF THE ATMOSPHERE ARE
EXPECTED TO REMAIN RATHER DRY...LOWER LEVELS WILL LIKELY REMAIN A
BIT MORE MOIST DUE TO THE RAINFALL FROM TUESDAY EVENT AND LOW
LEVEL NORTHEAST WIND TRAJECTORIES. SCT-BKN CLOUDS ARE EXPECTED FOR
OUT ADJACENT WESTERN NEW ENGLAND COUNTIES WITH DOWNSLOPING
COMPONENT INTO THE HUDSON RIVER VALLEY FOR AT LEAST A PTSUNNY DAY.
AS FOR TEMPERATURES...A MODEL BLEND APPROACH WAS UTILIZED WHICH
DOWNPLAYS THE COOLER VALUES WITHIN THE GFS MOS AND THE MUCH WARMER
VALUES SEEN IN THE MET MOS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
THE MODELS HAVE STARTED TO COME INTO BETTER AGREEMENT REGARDING THE
EXTENDED PERIOD...FOR THE PERIOD BEGINNING ON WEDNESDAY EVENING. AT
THIS POINT...IT APPEARS THAT THE UPPER TROUGH RESPONSIBLE FOR
BRINGING THE MID WEEK WET WEATHER WILL BE PROGRESSIVE AND CONTINUE
TO MOVE EASTWARD ACROSS CANADA. ALTHOUGH THE SURFACE FRONTAL
BOUNDARY WON/T MAKE A CLEAN SWEEP OUT TO SEA...IT LOOKS TO GENERALLY
WASH OUT ACROSS NEW ENGLAND TO THE EAST OF OUR REGION. ALSO...WHILE
IT STILL APPEARS THAT A SURFACE WAVE MAY DEVELOP ALONG THIS
FRONT...THE LATEST 00 UTC ECMWF/GFS BOTH SHOW A WEAK LOW REMAINING
OFF THE COAST...WITH HIGH PRESSURE BUILDING INTO OUR AREA FROM
SOUTHERN CANADA. WHILE WE STILL MAY HAVE A LOW CHC/SLIGHT CHC FOR A
RAIN SHOWER ACROSS THE REGION /ESP FOR EASTERN AREAS/ FOR WED NIGHT
INTO THURSDAY DUE TO THE PROXIMITY OF THE SFC BOUNDARY...IT DOESN/T
APPEAR TO BE A WASHOUT BY ANY STRETCH. SKIES LOOK TO RANGE FROM
PARTLY CLOUDY IN WESTERN AREAS...TO MOSTLY CLOUDY FOR WESTERN NEW
ENGLAND...DUE TO THE WEAK NE SURFACE FLOW IN PLACE. MIN TEMPS LOOK
TO RANGE FROM THE MID 40S TO UPPER 50S FOR WED NIGHT...WITH MAX
TEMPS GENERALLY IN THE 70S ON THURSDAY.
STRONG UPPER RIDGING LOOKS TO BUILD INTO THE REGION FOR FRIDAY INTO
THE WEEKEND AS A RIDGE OVER THE GREAT LAKES BENDS NORTHEASTWARD INTO
OUR AREA. ALTHOUGH THE MODELS SHOW A CLOSED OFF 500 HPA LOW ACROSS
THE WESTERN ATLANTIC...IT LOOKS TO STAY FAR ENOUGH EAST OF OUR AREA
TO BE OF ANY CONCERN FOR US. WITH THE BUILDING RIDGE...AND WARMING
TEMPS ALOFT...ENOUGH OF A CAP LOOKS TO BE IN PLACE TO PREVENT ANY
CONVECTION FROM FIRING UP...SO HAVE GONE WITH A DRY FORECAST FOR
FRIDAY ONWARD. VALLEY MAX TEMPS SHOULD BE GRADUALLY WARMER AND
WARMER EACH DAY...WITH UPPER 70S TO NEAR 80 FOR FRIDAY...LOW 80S FOR
SATURDAY...AND LOW TO MID 80S FOR SUNDAY. SKIES GENERALLY LOOK
MOSTLY CLEAR TO PARTLY CLOUDY. AT THIS POINT...DEWPOINTS DON/T LOOK
TOO MUGGY JUST YET...WITH TDS GENERALLY IN THE 50S F.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
HIGH PRESSURE WILL REMAIN ANCHORED OFF THE NEW ENGLAND COAST
THROUGH TONIGHT. A WARM FRONT APPROACHING FROM THE SOUTHWEST WILL
SPREAD CLOUDS...AND SHOWERS INTO THE REGION FOR TUESDAY AFTERNOON
AND NIGHT.
EXPECT VFR CONDITIONS THROUGH AT LEAST EARLY TONIGHT. THEN...AS A
MOIST S/SE FLOW CONTINUES...SOME LOW CLOUDS ARE EXPECTED TO
DEVELOP AND SPREAD NORTHWARD AFTER 06Z/TUE. THIS SHOULD LEAD TO
MVFR CIGS DEVELOPING PRIOR TO 12Z/TUE...WITH A CHANCE FOR IFR CIGS
AT KPSF...AND POSSIBLY KPOU. THERE IS A SLIGHT CHANCE THAT IFR
CIGS MAY SPREAD EVEN FURTHER N...BUT AT THIS TIME...CONFIDENCE NOT
QUITE HIGH ENOUGH TO INCLUDE AT KALB/KGFL.
AREAS OF MVFR CIGS WILL LINGER THROUGH 14Z-15Z/TUE...WITH SOME
POSSIBILITY OF IMPROVEMENT INTO THE LOW VFR RANGE THEREAFTER.
HOWEVER...SHOWERS SHOULD DEVELOP ACROSS WESTERN AND CENTRAL NYS
DURING THE MORNING...AND MAY IMPACT TAF SITES WEST OF THE HUDSON
RIVER AFTER 16Z/TUE.
SOUTH TO SOUTHEAST WINDS WILL REMAIN AT 8-12 KT THIS
AFTERNOON...WITH SOME GUSTS OF 20-25 KT POSSIBLE...ESP AT KALB DUE
TO FUNNELING EFFECTS UP THE HUDSON RIVER VALLEY. SOUTH TO
SOUTHEAST WINDS WILL DIMINISH TO 5-10 KT TONIGHT...THEN INCREASE
AGAIN TO 8-12 KT TUE MORNING...WITH SOME GUSTS OF 20-25 KT POSSIBLE.
OUTLOOK...
TUE-TUE NT...VFR/MVFR. CHC IFR. AFTERNOON SHRA/TSRA LIKELY.
WED...VFR/MVFR. SHRA POSSIBLE EARLY.
THU/SAT...VFR. SLIGHT CHC -SHRA. CHC LATE NIGHT/EARLY MORNING
MVFR/IFR IN FOG/STRATUS.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS ARE EXPECTED OVER THE NEXT SEVERAL DAYS.
A SOUTH TO SOUTHEAST WIND WILL INCREASE TO AROUND 10 MPH TODAY WITH
DRY WEATHER EXPECTED. AFTERNOON RH VALUES WILL DROP INTO THE 35-50
PERCENT...HIGHEST TO THE WEST OF ALBANY. MINIMUM RH VALUES TONIGHT
REBOUND TO GREATER THAN 80 PERCENT.
A WETTING RAIN IS EXPECTED ON TUESDAY TO FURTHER REDUCE FIRE
WEATHER CONCERNS.
&&
.HYDROLOGY...
A MODERATE RAINFALL EVENT IS EXPECTED ON TUESDAY ACROSS THE HYDRO
SERVICE AREA. LATEST MODEL GUIDANCE SUPPORTS A ROBUST MOISTURE
TRANSPORT THAT SHOULD GENERATE AT LEAST BROKEN COVERAGE OF
MODERATE TO HEAVY EMBEDDED CONVECTIVE RAINFALL RATES. EXPECTING
THE RAINFALL TO BE OROGRAPHICALLY ENHANCED ACROSS PORTIONS OF THE
CATSKILLS....BERKSHIRES AND SOUTHERN GREENS. PWAT ANOMALIES OF 2
TO 3 STD DEV ABOVE NORMAL...A >40 KT SOUTHERLY LOW LEVEL JET
HELPING TO ENHANCE ISENTROPIC LIFT AND OROGRAPHICS SHOULD HELP
ENHANCE RAINFALL RATES...AND THUS EXPECTING SOME LOCALLY HEAVIER
TOTALS FOR THE EVENT AT OR ABOVE 2 INCHES.
THIS SHOULD PRODUCE RISES ON AREA RIVERS AND STREAMS...BUT NO
FLOODING IS EXPECTED ON THE STREAMS AND RIVERS. LATEST RUN OF THE
MMEFS GUIDANCE ALSO SUPPORT THIS IDEA WITH NO POINTS EXPECTED TO
CLIMB ABOVE FLOOD STAGE.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...KL/BGM
NEAR TERM...KL/BGM
SHORT TERM...BGM
LONG TERM...FRUGIS
AVIATION...KL
FIRE WEATHER...BGM
HYDROLOGY...BGM
AREA FORECAST DISCUSSION
NWS ALBANY NY
1108 AM EDT MON JUN 11 2012
.SYNOPSIS...
HIGH PRESSURE ALOFT WILL BUILD INTO THE REGION THROUGH
TODAY...WITH WARM AND SOMEWHAT HUMID CONDITIONS THROUGH TONIGHT.
WIDESPREAD SHOWERS AND THUNDERSTORMS WILL RETURN FOR TUESDAY INTO
EARLY WEDNESDAY ASSOCIATED WITH A PERIOD OF MODERATE TO HEAVY
RAINFALL AS A FRONTAL BOUNDARY SLOWLY CROSSES THE REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 935 AM EDT...STRATUS CLOUDS CONTINUE TO EXPAND N AND
W...ACROSS NW CT...THE MID HUDSON VALLEY REGION AND
BERKSHIRES...AS WELL AS ACROSS THE SE CATSKILLS. AREAS OF LOW
CLOUDS/FOG ACROSS THE WESTERN ADIRONDACKS...AND PORTIONS OF THE
HELDERBERGS APPEARS TO BE DECREASING.
HAVE MADE SOME CHANGES TO GRIDDED DATABASE BASED ON RECENT
OBS...12Z UA SOUNDINGS...AND LATEST RAP/HRRR. FIRST WAS TO EXPAND THE
SLIGHT CHC POPS A BIT FURTHER SOUTH INTO THE CENTRAL AND WESTERN
MOHAWK VALLEY. THE LATEST RAP AND HRRR CONTINUE TO INDICATE
POCKETS OF FAIRLY DECENT INSTABILITY DEVELOPING THIS AFTERNOON IN
THIS REGION. IN ADDITION...THIS REGION WILL BE CLOSER TO A WEAK
BOUNDARY...SEPARATING A SLIGHTLY COOLER MODIFIED MARINE AIR MASS
TO THE E AND S...FROM A WARMER...MORE CONTINENTAL AIR MASS TO THE
N AND W.
ELSEWHERE...HAVE INCREASED CLOUDS COVERAGE AND LOWERED MAX TEMPS
ACROSS WESTERN NEW ENGLAND...AND THE MID HUDSON VALLEY REGION. AS
THE AFOREMENTIONED MODIFIED MARINE AIR CONTINUES TO WORK N AND
W...MAX TEMPS MAY FAIL TO REACH 80 ACROSS THE BERKSHIRES/SOUTHERN
GREENS...LITCHFIELD CO AND THE MID HUDSON VALLEY.
ELSEWHERE...STILL EXPECT MAXES TO REACH 80-85 ACROSS THE UPPER
HUDSON VALLEY FROM ALBANY NORTH...AND MID 80S ACROSS THE CENTRAL
AND WESTERN MOHAWK VALLEY...WHERE EVEN SOME UPPER 80S ARE
POSSIBLE.
WILL NEED TO WATCH HOW FAR N AND W THE LOWER CLOUDS REACH...AS
THIS MAY REQUIRE ADDITIONAL MODIFICATIONS TO MAX TEMPS/TOWARD
LOWER VALUES/WITHIN THE CAPITAL REGION SHOULD MORE CLOUDS FORM.
FOR TONIGHT...ANY CONVECTION SHOULD QUICKLY DISSIPATE THIS EVENING
AS THE UPPER LEVEL RIDGE AXIS SLIDES FURTHER OFFSHORE. THIS WILL
ALLOW THE UPSTREAM NORTHERN PLAINS TROUGH TO MIGRATE FURTHER EAST
TOWARD THE CENTRAL GREAT LAKES REGION. ALONG WITH ITS
APPROACH...MOISTURE ADVECTION FROM THE SOUTHEAST CONUS AND OHIO
VALLEY WILL ADVANCE NORTHWARD. FORECAST SOUNDINGS SUPPORT AN
ENTRAINMENT OF LOW LEVEL STRATUS FROM THE ATLANTIC YET RATHER DRY
BETWEEN 850-500MB TO KEEP THE CHANCE OF PRECIP WEST OF THE REGION.
EXPECTATIONS ARE FOR AN INCREASING CLOUD COVER AND A MILD
OVERNIGHT WITH LOWS MAINLY INTO THE 60S.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
RAINFALL POTENTIAL INCREASES FROM WEST TO EAST AS THE LOW LEVEL
JET INCREASES TO >40KTS TO ASSIST WITH RAPID MOISTURE TRANSPORT
INTO THE CWFA. NCEP MODEL SUITE ARE IN EXCELLENT AGREEMENT WITH A
PERIOD OF MODERATE RAINFALL TO MOVE ACROSS THE REGION ON TUESDAY.
INSTABILITY PARAMETERS ARE NOT FAVORABLE FOR SEVERE
WEATHER...HOWEVER...MID LEVEL VALUES PER THE SHOWALTERS STILL
SUPPORT EMBEDDED DEEPER CONVECTION. PWATS ARE PROGGED TO CLIMB IN
EXCESS OF 1.75" WITH UPSTREAM VALUES CLOSE TO 2.00". THESE VALUES
ARE 2-3 STANDARD DEVIATIONS ABOVE NORMAL TO SUPPORT EMBEDDED
PERIODS OF HEAVY RAINFALL. FAVORED UPSLOPE REGIONS OF THE
CATSKILLS...NW CT INTO THE BERKS AND SOUTHERN VT MAY ENHANCE
RAINFALL RATES. SEE THE HYDRO DISCUSSION FOR FURTHER DETAILS ON
THE RAINFALL POTENTIAL IMPACTS. OTHERWISE...RATHER HIGH POPS
EXPECTED DURING THE DAY WITH TEMPERATURES A BIT COOLER DUE TO THE
MARINE INFLUENCE...CLOUDS AND PRECIP WITH HIGHS MAINLY IN THE MID
60S TO LOWER 70S.
MODELS HAVE COME AROUND TO THE ECMWF OF THE PAST SEVERAL DAYS
WITH A MORE PROGRESSIVE FROPA TUESDAY EVENING. SO WE WILL
GRADUALLY LOWER POPS FROM WEST TO EAST ALONG WITH IMPROVEMENTS TO
THE SKY COVER. HOWEVER...EAST OF THE HUDSON RIVER...THOSE CLOUDS
WILL LIKELY LINGER LONGER UNTIL THE FRONT HAS CLEARED THE EASTERN
SEABOARD.
CONFIDENCE CONTINUES TO INCREASE THAT WEDNESDAY SHOULD TURN OUT TO
BE A DRIER DAY. WHILE THE MID LEVELS OF THE ATMOSPHERE ARE
EXPECTED TO REMAIN RATHER DRY...LOWER LEVELS WILL LIKELY REMAIN A
BIT MORE MOIST DUE TO THE RAINFALL FROM TUESDAY EVENT AND LOW
LEVEL NORTHEAST WIND TRAJECTORIES. SCT-BKN CLOUDS ARE EXPECTED FOR
OUT ADJACENT WESTERN NEW ENGLAND COUNTIES WITH DOWNSLOPING
COMPONENT INTO THE HUDSON RIVER VALLEY FOR AT LEAST A PTSUNNY DAY.
AS FOR TEMPERATURES...A MODEL BLEND APPROACH WAS UTILIZED WHICH
DOWNPLAYS THE COOLER VALUES WITHIN THE GFS MOS AND THE MUCH WARMER
VALUES SEEN IN THE MET MOS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
THE MODELS HAVE STARTED TO COME INTO BETTER AGREEMENT REGARDING THE
EXTENDED PERIOD...FOR THE PERIOD BEGINNING ON WEDNESDAY EVENING. AT
THIS POINT...IT APPEARS THAT THE UPPER TROUGH RESPONSIBLE FOR
BRINGING THE MID WEEK WET WEATHER WILL BE PROGRESSIVE AND CONTINUE
TO MOVE EASTWARD ACROSS CANADA. ALTHOUGH THE SURFACE FRONTAL
BOUNDARY WON/T MAKE A CLEAN SWEEP OUT TO SEA...IT LOOKS TO GENERALLY
WASH OUT ACROSS NEW ENGLAND TO THE EAST OF OUR REGION. ALSO...WHILE
IT STILL APPEARS THAT A SURFACE WAVE MAY DEVELOP ALONG THIS
FRONT...THE LATEST 00 UTC ECMWF/GFS BOTH SHOW A WEAK LOW REMAINING
OFF THE COAST...WITH HIGH PRESSURE BUILDING INTO OUR AREA FROM
SOUTHERN CANADA. WHILE WE STILL MAY HAVE A LOW CHC/SLIGHT CHC FOR A
RAIN SHOWER ACROSS THE REGION /ESP FOR EASTERN AREAS/ FOR WED NIGHT
INTO THURSDAY DUE TO THE PROXIMITY OF THE SFC BOUNDARY...IT DOESN/T
APPEAR TO BE A WASHOUT BY ANY STRETCH. SKIES LOOK TO RANGE FROM
PARTLY CLOUDY IN WESTERN AREAS...TO MOSTLY CLOUDY FOR WESTERN NEW
ENGLAND...DUE TO THE WEAK NE SURFACE FLOW IN PLACE. MIN TEMPS LOOK
TO RANGE FROM THE MID 40S TO UPPER 50S FOR WED NIGHT...WITH MAX
TEMPS GENERALLY IN THE 70S ON THURSDAY.
STRONG UPPER RIDGING LOOKS TO BUILD INTO THE REGION FOR FRIDAY INTO
THE WEEKEND AS A RIDGE OVER THE GREAT LAKES BENDS NORTHEASTWARD INTO
OUR AREA. ALTHOUGH THE MODELS SHOW A CLOSED OFF 500 HPA LOW ACROSS
THE WESTERN ATLANTIC...IT LOOKS TO STAY FAR ENOUGH EAST OF OUR AREA
TO BE OF ANY CONCERN FOR US. WITH THE BUILDING RIDGE...AND WARMING
TEMPS ALOFT...ENOUGH OF A CAP LOOKS TO BE IN PLACE TO PREVENT ANY
CONVECTION FROM FIRING UP...SO HAVE GONE WITH A DRY FORECAST FOR
FRIDAY ONWARD. VALLEY MAX TEMPS SHOULD BE GRADUALLY WARMER AND
WARMER EACH DAY...WITH UPPER 70S TO NEAR 80 FOR FRIDAY...LOW 80S FOR
SATURDAY...AND LOW TO MID 80S FOR SUNDAY. SKIES GENERALLY LOOK
MOSTLY CLEAR TO PARTLY CLOUDY. AT THIS POINT...DEWPOINTS DON/T LOOK
TOO MUGGY JUST YET...WITH TDS GENERALLY IN THE 50S F.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
A BATCH OF STRATUS CLOUDS OF 3-5 KFT OVER PORTIONS OF THE
REGION...ALONG WITH A LIGHT S-SW WIND...PREVENTED ANY IFR FOG FROM
DEVELOPING THIS MORNING. SOME MVFR BR IS POSSIBLE FOR A BRIEF TIME
AT KPOU...OTHERWISE...VFR CONDITIONS SHOULD CONTINUE AT ALL
TAF SITES THIS MORNING. SCT DIURNAL CU WILL DEVELOP WITHIN DAYTIME
HEATING BY THE LATE MORNING. SOME PASSING HIGH CIRRUS IS POSSIBLE AS
WELL. WITHIN DAYTIME MIXING...SOUTHERLY WINDS WILL AVERAGE AROUND 10
KTS.
AN APPROACHING FRONTAL SYSTEM WILL SPREAD MID AND HIGH LEVEL CLOUDS
ACROSS THE REGION TONIGHT. IN ADDITION...LIGHT S-SE SFC WINDS WILL
CONTINUE AS WELL. THESE TWO FACTORS SHOULD PREVENT ANY RADIATIONAL
FOG FROM DEVELOPING...KEEPING FLYING CONDITIONS MAINLY VFR.
HOWEVER...THE MOIST SOUTHERLY FLOW MAY ALLOW FOR SOME MVFR STRATUS
TO MOVE INTO KPOU FOR THE SECOND HALF OF THE NIGHT.
OUTLOOK...
TUE-TUE NT...VFR TO MVFR. SHRA/TSRA LIKELY.
WED...VFR/MVFR. SHRA POSSIBLE EARLY.
THU/FRI...VFR. SLIGHT CHC -SHRA. CHC LATE NIGHT/EARLY MORNING
MVFR/IFR IN FOG/STRATUS.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS ARE EXPECTED OVER THE NEXT SEVERAL DAYS.
A SOUTH TO SOUTHEAST WIND WILL INCREASE TO AROUND 10 MPH TODAY WITH
DRY WEATHER EXPECTED. AFTERNOON RH VALUES WILL DROP INTO THE 35-50
PERCENT...HIGHEST TO THE WEST OF ALBANY. MINIMUM RH VALUES TONIGHT
REBOUND TO GREATER THAN 80 PERCENT.
A WETTING RAIN IS EXPECTED ON TUESDAY TO FURTHER REDUCE FIRE
WEATHER CONCERNS.
&&
.HYDROLOGY...
A MODERATE RAINFALL EVENT IS EXPECTED ON TUESDAY ACROSS THE HYDRO
SERVICE AREA. LATEST MODEL GUIDANCE SUPPORTS A ROBUST MOISTURE
TRANSPORT THAT SHOULD GENERATE AT LEAST BROKEN COVERAGE OF
MODERATE TO HEAVY EMBEDDED CONVECTIVE RAINFALL RATES. EXPECTING
THE RAINFALL TO BE OROGRAPHICALLY ENHANCED ACROSS PORTIONS OF THE
CATSKILLS....BERKSHIRES AND SOUTHERN GREENS. PWAT ANOMALIES OF 2
TO 3 STD DEV ABOVE NORMAL...A >40 KT SOUTHERLY LOW LEVEL JET
HELPING TO ENHANCE ISENTROPIC LIFT AND OROGRAPHICS SHOULD HELP
ENHANCE RAINFALL RATES...AND THUS EXPECTING SOME LOCALLY HEAVIER
TOTALS FOR THE EVENT AT OR ABOVE 2 INCHES.
THIS SHOULD PRODUCE RISES ON AREA RIVERS AND STREAMS...BUT NO
FLOODING IS EXPECTED ON THE STREAMS AND RIVERS. LATEST RUN OF THE
MMEFS GUIDANCE ALSO SUPPORT THIS IDEA WITH NO POINTS EXPECTED TO
CLIMB ABOVE FLOOD STAGE.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...KL/BGM
NEAR TERM...KL/BGM
SHORT TERM...BGM
LONG TERM...FRUGIS
AVIATION...KL/FRUGIS
FIRE WEATHER...BGM
HYDROLOGY...BGM
AREA FORECAST DISCUSSION
NWS ALBANY NY
937 AM EDT MON JUN 11 2012
.SYNOPSIS...
HIGH PRESSURE ALOFT WILL BUILD INTO THE REGION THROUGH
TODAY...WITH WARM AND SOMEWHAT HUMID CONDITIONS THROUGH TONIGHT.
WIDESPREAD SHOWERS AND THUNDERSTORMS WILL RETURN FOR TUESDAY INTO
EARLY WEDNESDAY ASSOCIATED WITH A PERIOD OF MODERATE TO HEAVY
RAINFALL AS A FRONTAL BOUNDARY SLOWLY CROSSES THE REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 935 AM EDT...STRATUS CLOUDS CONTINUE TO EXPAND N AND
W...ACROSS NW CT...THE MID HUDSON VALLEY REGION AND
BERKSHIRES...AS WELL AS ACROSS THE SE CATSKILLS. AREAS OF LOW
CLOUDS/FOG ACROSS THE WESTERN ADIRONDACKS...AND PORTIONS OF THE
HELDERBERGS APPEARS TO BE DECREASING.
HAVE MADE SOME CHANGES TO GRIDDED DATABASE BASED ON RECENT
OBS...12Z UA SOUNDINGS...AND LATEST RAP/HRRR. FIRST WAS TO EXPAND THE
SLIGHT CHC POPS A BIT FURTHER SOUTH INTO THE CENTRAL AND WESTERN
MOHAWK VALLEY. THE LATEST RAP AND HRRR CONTINUE TO INDICATE
POCKETS OF FAIRLY DECENT INSTABILITY DEVELOPING THIS AFTERNOON IN
THIS REGION. IN ADDITION...THIS REGION WILL BE CLOSER TO A WEAK
BOUNDARY...SEPARATING A SLIGHTLY COOLER MODIFIED MARINE AIR MASS
TO THE E AND S...FROM A WARMER...MORE CONTINENTAL AIR MASS TO THE
N AND W.
ELSEWHERE...HAVE INCREASED CLOUDS COVERAGE AND LOWERED MAX TEMPS
ACROSS WESTERN NEW ENGLAND...AND THE MID HUDSON VALLEY REGION. AS
THE AFOREMENTIONED MODIFIED MARINE AIR CONTINUES TO WORK N AND
W...MAX TEMPS MAY FAIL TO REACH 80 ACROSS THE BERKSHIRES/SOUTHERN
GREENS...LITCHFIELD CO AND THE MID HUDSON VALLEY.
ELSEWHERE...STILL EXPECT MAXES TO REACH 80-85 ACROSS THE UPPER
HUDSON VALLEY FROM ALBANY NORTH...AND MID 80S ACROSS THE CENTRAL
AND WESTERN MOHAWK VALLEY...WHERE EVEN SOME UPPER 80S ARE
POSSIBLE.
WILL WIL NEED TO WATCH HOW FAR N AND W THE LOWER CLOUDS REACH...AS
THIS MAY REQUIRE ADDITIONAL MODIFICATIONS TO MAX TEMPS/TOWARD
LOWER VALUES/WITHIN THE CAPITAL REGION SHOULD MORE CLOUDS FORM.
FOR TONIGHT...ANY CONVECTION SHOULD QUICKLY DISSIPATE THIS EVENING
AS THE UPPER LEVEL RIDGE AXIS SLIDES FURTHER OFFSHORE. THIS WILL
ALLOW THE UPSTREAM NORTHERN PLAINS TROUGH TO MIGRATE FURTHER EAST
TOWARD THE CENTRAL GREAT LAKES REGION. ALONG WITH ITS
APPROACH...MOISTURE ADVECTION FROM THE SOUTHEAST CONUS AND OHIO
VALLEY WILL ADVANCE NORTHWARD. FORECAST SOUNDINGS SUPPORT AN
ENTRAINMENT OF LOW LEVEL STRATUS FROM THE ATLANTIC YET RATHER DRY
BETWEEN 850-500MB TO KEEP THE CHANCE OF PRECIP WEST OF THE REGION.
EXPECTATIONS ARE FOR AN INCREASING CLOUD COVER AND A MILD
OVERNIGHT WITH LOWS MAINLY INTO THE 60S.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
RAINFALL POTENTIAL INCREASES FROM WEST TO EAST AS THE LOW LEVEL
JET INCREASES TO >40KTS TO ASSIST WITH RAPID MOISTURE TRANSPORT
INTO THE CWFA. NCEP MODEL SUITE ARE IN EXCELLENT AGREEMENT WITH A
PERIOD OF MODERATE RAINFALL TO MOVE ACROSS THE REGION ON TUESDAY.
INSTABILITY PARAMETERS ARE NOT FAVORABLE FOR SEVERE
WEATHER...HOWEVER...MID LEVEL VALUES PER THE SHOWALTERS STILL
SUPPORT EMBEDDED DEEPER CONVECTION. PWATS ARE PROGGED TO CLIMB IN
EXCESS OF 1.75" WITH UPSTREAM VALUES CLOSE TO 2.00". THESE VALUES
ARE 2-3 STANDARD DEVIATIONS ABOVE NORMAL TO SUPPORT EMBEDDED
PERIODS OF HEAVY RAINFALL. FAVORED UPSLOPE REGIONS OF THE
CATSKILLS...NW CT INTO THE BERKS AND SOUTHERN VT MAY ENHANCE
RAINFALL RATES. SEE THE HYDRO DISCUSSION FOR FURTHER DETAILS ON
THE RAINFALL POTENTIAL IMPACTS. OTHERWISE...RATHER HIGH POPS
EXPECTED DURING THE DAY WITH TEMPERATURES A BIT COOLER DUE TO THE
MARINE INFLUENCE...CLOUDS AND PRECIP WITH HIGHS MAINLY IN THE MID
60S TO LOWER 70S.
MODELS HAVE COME AROUND TO THE ECMWF OF THE PAST SEVERAL DAYS
WITH A MORE PROGRESSIVE FROPA TUESDAY EVENING. SO WE WILL
GRADUALLY LOWER POPS FROM WEST TO EAST ALONG WITH IMPROVEMENTS TO
THE SKY COVER. HOWEVER...EAST OF THE HUDSON RIVER...THOSE CLOUDS
WILL LIKELY LINGER LONGER UNTIL THE FRONT HAS CLEARED THE EASTERN
SEABOARD.
CONFIDENCE CONTINUES TO INCREASE THAT WEDNESDAY SHOULD TURN OUT TO
BE A DRIER DAY. WHILE THE MID LEVELS OF THE ATMOSPHERE ARE
EXPECTED TO REMAIN RATHER DRY...LOWER LEVELS WILL LIKELY REMAIN A
BIT MORE MOIST DUE TO THE RAINFALL FROM TUESDAY EVENT AND LOW
LEVEL NORTHEAST WIND TRAJECTORIES. SCT-BKN CLOUDS ARE EXPECTED FOR
OUT ADJACENT WESTERN NEW ENGLAND COUNTIES WITH DOWNSLOPING
COMPONENT INTO THE HUDSON RIVER VALLEY FOR AT LEAST A PTSUNNY DAY.
AS FOR TEMPERATURES...A MODEL BLEND APPROACH WAS UTILIZED WHICH
DOWNPLAYS THE COOLER VALUES WITHIN THE GFS MOS AND THE MUCH WARMER
VALUES SEEN IN THE MET MOS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
THE MODELS HAVE STARTED TO COME INTO BETTER AGREEMENT REGARDING THE
EXTENDED PERIOD...FOR THE PERIOD BEGINNING ON WEDNESDAY EVENING. AT
THIS POINT...IT APPEARS THAT THE UPPER TROUGH RESPONSIBLE FOR
BRINGING THE MID WEEK WET WEATHER WILL BE PROGRESSIVE AND CONTINUE
TO MOVE EASTWARD ACROSS CANADA. ALTHOUGH THE SURFACE FRONTAL
BOUNDARY WON/T MAKE A CLEAN SWEEP OUT TO SEA...IT LOOKS TO GENERALLY
WASH OUT ACROSS NEW ENGLAND TO THE EAST OF OUR REGION. ALSO...WHILE
IT STILL APPEARS THAT A SURFACE WAVE MAY DEVELOP ALONG THIS
FRONT...THE LATEST 00 UTC ECMWF/GFS BOTH SHOW A WEAK LOW REMAINING
OFF THE COAST...WITH HIGH PRESSURE BUILDING INTO OUR AREA FROM
SOUTHERN CANADA. WHILE WE STILL MAY HAVE A LOW CHC/SLIGHT CHC FOR A
RAIN SHOWER ACROSS THE REGION /ESP FOR EASTERN AREAS/ FOR WED NIGHT
INTO THURSDAY DUE TO THE PROXIMITY OF THE SFC BOUNDARY...IT DOESN/T
APPEAR TO BE A WASHOUT BY ANY STRETCH. SKIES LOOK TO RANGE FROM
PARTLY CLOUDY IN WESTERN AREAS...TO MOSTLY CLOUDY FOR WESTERN NEW
ENGLAND...DUE TO THE WEAK NE SURFACE FLOW IN PLACE. MIN TEMPS LOOK
TO RANGE FROM THE MID 40S TO UPPER 50S FOR WED NIGHT...WITH MAX
TEMPS GENERALLY IN THE 70S ON THURSDAY.
STRONG UPPER RIDGING LOOKS TO BUILD INTO THE REGION FOR FRIDAY INTO
THE WEEKEND AS A RIDGE OVER THE GREAT LAKES BENDS NORTHEASTWARD INTO
OUR AREA. ALTHOUGH THE MODELS SHOW A CLOSED OFF 500 HPA LOW ACROSS
THE WESTERN ATLANTIC...IT LOOKS TO STAY FAR ENOUGH EAST OF OUR AREA
TO BE OF ANY CONCERN FOR US. WITH THE BUILDING RIDGE...AND WARMING
TEMPS ALOFT...ENOUGH OF A CAP LOOKS TO BE IN PLACE TO PREVENT ANY
CONVECTION FROM FIRING UP...SO HAVE GONE WITH A DRY FORECAST FOR
FRIDAY ONWARD. VALLEY MAX TEMPS SHOULD BE GRADUALLY WARMER AND
WARMER EACH DAY...WITH UPPER 70S TO NEAR 80 FOR FRIDAY...LOW 80S FOR
SATURDAY...AND LOW TO MID 80S FOR SUNDAY. SKIES GENERALLY LOOK
MOSTLY CLEAR TO PARTLY CLOUDY. AT THIS POINT...DEWPOINTS DON/T LOOK
TOO MUGGY JUST YET...WITH TDS GENERALLY IN THE 50S F.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
A BATCH OF STRATUS CLOUDS OF 3-5 KFT OVER PORTIONS OF THE
REGION...ALONG WITH A LIGHT S-SW WIND...PREVENTED ANY IFR FOG FROM
DEVELOPING THIS MORNING. SOME MVFR BR IS POSSIBLE FOR A BRIEF TIME
AT KPOU...OTHERWISE...VFR CONDITIONS SHOULD CONTINUE AT ALL
TAF SITES THIS MORNING. SCT DIURNAL CU WILL DEVELOP WITHIN DAYTIME
HEATING BY THE LATE MORNING. SOME PASSING HIGH CIRRUS IS POSSIBLE AS
WELL. WITHIN DAYTIME MIXING...SOUTHERLY WINDS WILL AVERAGE AROUND 10
KTS.
AN APPROACHING FRONTAL SYSTEM WILL SPREAD MID AND HIGH LEVEL CLOUDS
ACROSS THE REGION TONIGHT. IN ADDITION...LIGHT S-SE SFC WINDS WILL
CONTINUE AS WELL. THESE TWO FACTORS SHOULD PREVENT ANY RADIATIONAL
FOG FROM DEVELOPING...KEEPING FLYING CONDITIONS MAINLY VFR.
HOWEVER...THE MOIST SOUTHERLY FLOW MAY ALLOW FOR SOME MVFR STRATUS
TO MOVE INTO KPOU FOR THE SECOND HALF OF THE NIGHT.
OUTLOOK...
TUE-TUE NT...VFR TO MVFR. SHRA/TSRA LIKELY.
WED...VFR/MVFR. SHRA POSSIBLE EARLY.
THU/FRI...VFR. SLIGHT CHC -SHRA. CHC LATE NIGHT/EARLY MORNING
MVFR/IFR IN FOG/STRATUS.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS ARE EXPECTED OVER THE NEXT SEVERAL DAYS.
A SOUTH TO SOUTHEAST WIND WILL INCREASE TO AROUND 10 MPH TODAY WITH
DRY WEATHER EXPECTED. AFTERNOON RH VALUES WILL DROP INTO THE 35-50
PERCENT...HIGHEST TO THE WEST OF ALBANY. MINIMUM RH VALUES TONIGHT
REBOUND TO GREATER THAN 80 PERCENT.
A WETTING RAIN IS EXPECTED ON TUESDAY TO FURTHER REDUCE FIRE
WEATHER CONCERNS.
&&
.HYDROLOGY...
A MODERATE RAINFALL EVENT IS EXPECTED ON TUESDAY ACROSS THE HYDRO
SERVICE AREA. LATEST MODEL GUIDANCE SUPPORTS A ROBUST MOISTURE
TRANSPORT THAT SHOULD GENERATE AT LEAST BROKEN COVERAGE OF
MODERATE TO HEAVY EMBEDDED CONVECTIVE RAINFALL RATES. EXPECTING
THE RAINFALL TO BE OROGRAPHICALLY ENHANCED ACROSS PORTIONS OF THE
CATSKILLS....BERKSHIRES AND SOUTHERN GREENS. PWAT ANOMALIES OF 2
TO 3 STD DEV ABOVE NORMAL...A >40 KT SOUTHERLY LOW LEVEL JET
HELPING TO ENHANCE ISENTROPIC LIFT AND OROGRAPHICS SHOULD HELP
ENHANCE RAINFALL RATES...AND THUS EXPECTING SOME LOCALLY HEAVIER
TOTALS FOR THE EVENT AT OR ABOVE 2 INCHES.
THIS SHOULD PRODUCE RISES ON AREA RIVERS AND STREAMS...BUT NO
FLOODING IS EXPECTED ON THE STREAMS AND RIVERS. LATEST RUN OF THE
MMEFS GUIDANCE ALSO SUPPORT THIS IDEA WITH NO POINTS EXPECTED TO
CLIMB ABOVE FLOOD STAGE.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...KL/BGM
NEAR TERM...KL/BGM
SHORT TERM...BGM
LONG TERM...FRUGIS
AVIATION...KL/FRUGIS
FIRE WEATHER...BGM
HYDROLOGY...BGM
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
511 PM CDT MON JUN 11 2012
.DISCUSSION...
320 PM CDT
THE FORECAST CONCERNS ARE VERY MINIMAL THROUGH THE REST OF THE
WEEK WITH A CONTINUED DRY PATTERN. WILL BE MONITORING FOR A FEW
STORMS LATE THIS AFTERNOON INTO EARLY EVENING...OTHERWISE THAT MAY
WILL LIKELY BE ALL THAT IS ON THE SCOPE FOR QUITE A WHILE.
ISOLATED SHOWERS WITH A FEW STORMS REDEVELOPING OVER COOK COUNTY
AND SOUTH ALONG THE IL/IN STATE LINE...WHICH IS ALONG AND JUST
AHEAD OF A WEAK CONVERGENT AXIS AND APPARENT SHORT WAVE SEEN ON
SATELLITE. MID 80S TEMPERATURES AND UPPER 60S DEW POINTS ALONG AND
AHEAD OF THIS CORRIDOR HAS BUILT SURFACE BASED CAPE TO AROUND OR
SLIGHTLY OVER 2000 J/KG. THIS CONVECTION SHOULD LAST LONGER THAN
THE PREVIOUS ACTIVITY NEAR NOON BEING CLOSER TO THE SHORT WAVE
CENTER AND HAVING MORE INSTABILITY TO WORK WITH. UPPER LEVEL WIND
SHEAR LOOKS TO BE AROUND A MEAGER 20 KT PER PROFILER ANALYSIS. THE
BEHAVIOR OF THE STORM CORES IS LIKELY TO BE SOMEWHAT PULSY WITH
INSTABILITY IN THE DRIVERS SEAT...AND WITH LIMITED ATTENDANT SHEAR
IT LEAVES ONLY A VERY SMALL CHANCE FOR ANY TYPE OF SEVERE ACTIVITY.
THE SYSTEM UPPER TROUGH CENTER IS LOCATED ALONG THE MN/WESTERN
QUEBEC BORDER WITH PRIMARY HEIGHT FALLS...THE UPPER JET AXIS...AND
ASSOCIATED DEEPER ASCENT MOVING EAST FROM THERE. THIS FORCING HAS
AIDED SOME SHOWER DEVELOPMENT ALONG THE SURFACE COLD FRONT IN
WESTERN WI. THE COOL FRONT EXTENDS SOUTH FROM THERE WHERE IT WILL
MOVE INTO NW IL BY 4 PM AND EAST THROUGH THE FORECAST AREA THIS
EVE. THE WIND SHIFT IS GRADUAL FROM WEST SOUTHWEST TO WEST
NORTHWEST ALONG THE BOUNDARY...AND IT IS ACTUALLY AHEAD OF THE
STRONGEST MOISTURE CONVERGENCE. SO OVERALL CONVERGENCE IS LIMITED
AND FEEL THAT WILL BE THE CASE WITH ANY CONVECTION THAT WERE TO
TRIGGER ALONG IT...WHICH IS NOW APPEARING DOUBTFUL IN OUR AREA.
THE HRRR AND OTHER EXPLICIT CONVECTIVE MODELS AGREE IN THIS
LIMITED COVERAGE.
THE COOL FRONT WILL MOVE THROUGH THE AREA THIS EVENING AND IT
LOOKS LIKE THE BOUNDARY LAYER WILL STAY MIXED AS IT DOES
SUCH...WITH SOME GUSTS UP TO 20 MPH AS THE PRESSURE RISE AXIS
MOVES THROUGH. SUNNY AND DRY WEATHER WILL THEN ONCE AGAIN BE THE
STORY AS CANADIAN HIGH PRESSURE MOVES OVERHEAD TUESDAY NIGHT INTO
WEDNESDAY. THE REALLY ONLY WEATHER OF INTEREST FROM DAY TO DAY WILL
BE HOW LOW DEW POINTS WILL DROP DURING THE AFTERNOON MIXING...AND
TO WHAT DEGREE OF COOLING WILL THERE BE FROM THE LAKE. NORTHWEST
WINDS WILL BEGIN TO DECREASE TUESDAY AFTERNOON...POTENTIALLY
ALLOWING FOR A SLIGHT LAKE BREEZE INTO IL...BUT LIKELY INTO IN.
THIS MAY NOT DEVELOP UNTIL LATE AFTERNOON THOUGH...SO WIDESPREAD
HIGHS IN THE MID TO UPPER 70S ARE EXPECTED. UPSTREAM DEW POINTS
TODAY HAVE BEEN IN THE LOWER TO MID 40S ACROSS EASTERN SD. THIS
AND POSSIBLY EVEN LOWER SHOULD BE REALIZED DURING TUESDAY AFTERNOON
WITH PROJECTED MIXING TO 850 MB. THE AFTERNOON HUMIDITY WILL
REMAIN LOW...UNDER 25 PERCENT...ON WEDNESDAY AFTERNOON WITH THE
SYNOPTIC FLOW TURNING NORTHEAST AND THEN EAST.
INFLUENCE FROM THE LAKE WILL LIKELY CONTINUE TO MOVE INTO CHICAGO
DURING THE AFTERNOON ALL THE WAY THROUGH SATURDAY. THE UPPER LEVEL
HEIGHTS AND LOW-LEVEL THERMAL RIDGE BUILD MORE INTO THE AREA
THURSDAY NIGHT INTO SATURDAY. THE EC HAS SHOWN IN THE UPPER LEVEL
SW FLOW THAT SHORT WAVE ENERGY IS POSSIBLE WITHIN THIS AND MAY
DAMPEN THE RIDGE SLIGHTLY SATURDAY NIGHT INTO SUNDAY...AND HAVE A
SMALL CHANCE FOR POPS DURING PART OF THAT TIME. OTHERWISE...HAVE
COLLABORATED GOING DRIER THAN POPS AND DEW POINTS FROM GUIDANCE
BLENDS IN THE EXTENDED PER PERSISTENCE AND AN OVERALL STAGNANT
PATTERN.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* DECREASING TSRA/SHRA THREAT.
* GUSTY WSW WINDS SHIFTING TO NW WITH COLD FROPA AROUND 02-03Z.
RATZER
//DISCUSSION...UPDATED 22Z...
ISOLATED SHRA/TSRA WHICH HAD FORMED SOUTHEAST OF ORD/MDW THIS
AFTERNOON HAVE WEAKENED AND MOVED OUT OVER SOUTHERN LAKE MICHIGAN.
PRE-FRONTAL TROUGH HAS MOVED THROUGH MOST OF TERMINAL AREA...WITH
WINDS SHIFTING WEST-SOUTHWEST BEHIND IT. THIS IS EXPECTED TO LIMIT
LOW LEVEL CONVERGENCE NECESSARY FOR ADDITIONAL TSRA/SHRA
DEVELOPMENT AHEAD OF COLD FRONT AND UPPER TROUGH WHICH WILL MOVE
ACROSS THE AREA LATER THIS EVENING. THUS WHILE ISOLATED SHRA/TSRA
CANT COMPLETELY BE RULED OUT OF THE REALM OF POSSIBILITY FOR THE
NEXT 3-4 HOURS...PROBABILITY OF THIS OCCURRING IS VERY LOW AND
WILL NOT CARRY ANY MENTION IN TAFS. AS INDICATED...WINDS SHIFTING
MORE WEST-SOUTHWEST WITH SOME GUSTS AROUND 20 KTS BETWEEN PRE-
FRONTAL TROUGH AND APPROACHING COLD FRONT...THEN WILL SHIFT WEST-
NORTHWEST AFTER COLD FROPA. TIMING OF FRONT IN THE 02-03Z TIME
FRAME STILL LOOKS REASONABLE. LATEST GUIDANCE INDICATES LOW LEVEL
MIXING MAY SUPPORT GUSTS FOR A FEW HOURS POST FROPA.
RATZER
PREVIOUS DISCUSSION FROM 18Z...
A COLD FRONT LIES ACROSS NORTHWEST WISCONSIN SOUTH INTO CENTRAL IOWA
THIS AFTERNOON. ONGOING THUNDERSTORMS CONTINUE ACROSS PORTIONS
SOUTHERN MISSOURI INTO CENTRAL ILLINOIS PROVIDING A CANOPY OF CLOUD
COVER ACROSS MUCH OF NORTHERN ILLINOIS THIS AFTERNOON. THERE IS SOME
CLEARING ACROSS PORTIONS OF EAST CENTRAL ILLINOIS AND NORTHWEST
INDIANA WHERE AN AXIS OF MODEST INSTABILITY HAS BEGUN TO DEVELOP. AN
UPPER LEVEL DISTURBANCE MOVING ACROSS IOWA EARLY THIS AFTERNOON WILL
PUSH EAST ACROSS NORTHERN ILLINOIS WITH THE POTENTIAL FOR ADDITIONAL
THUNDERSTORM DEVELOPMENT ACROSS THIS INSTABILITY AXIS MID AFTERNOON.
IT APPEARS THE THREAT SHOULD STAY SOUTHEAST/EAST OF ORD/MDW WITH
SOME POTENTIAL FOR GYY TO BE IMPACTED OR AT LEAST TO SEE ACTIVITY IN
THE VICINITY OF THE TERMINAL. MOVED UP VCTS AT GYY TO START OF TAF
GIVEN ACTIVITY CURRENTLY IN THE AREA JUST NORTHWEST OF THE
TERMINAL AT 18Z. LATE THIS EVENING...THE COLD FRONT IS EXPECTED TO
MOVE ACROSS THE AREA WITH WINDS BECOMING NORTHWEST. THERE MAY BE
ADDITIONAL THUNDERSTORMS THAT DEVELOP ALONG THE FRONT...BUT GIVEN
THE WEAK CONVERGENCE ALONG THE FRONT AND LOSS OF DIURNAL
HEATING...EXPECT COVERAGE TO BE ISOLATED TO WIDELY SCATTERED WITH
LOW THREAT OF BEING ON STATION. ON TUESDAY...HIGH PRESSURE WILL
BEGIN TO BUILD IN FROM THE NORTHWEST. WILL HAVE TO MONITOR THE
POSSIBILITY OF A LAKE BREEZE TURNING WINDS NORTHEAST IN THE
CHICAGO AREA LATE IN THE AFTERNOON.
BMD/RC
//ORD AND MDW CONFIDENCE...UPDATED 22Z...
* MEDIUM-HIGH CONFIDENCE IN WIND TRENDS THROUGH LATE EVENING.
* MEDIUM-HIGH CONFIDENCE IN NO ADDITIONAL TSRA/SHRA PRIOR TO COLD
FROPA THIS EVENING.
RATZER
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT THROUGH SATURDAY...VFR.
SUNDAY...VFR. SLIGHT CHC SHRA/TSRA.
BEACHLER
&&
.MARINE...
231 PM CDT
A LARGE LOW HAS MOVED INTO HUDSON BAY...WHILE HIGH PRESSURE SITS OFF
THE NEW ENGLAND COAST. THE UPPER LEVEL PRESSURE GRADIENT HAS
RELAXED...RESULTING IN SOUTH TO SOUTHWEST WINDS 15-25 KT ACROSS THE
LAKE THIS AFTERNOON. STRONGEST WINDS AROUND 25 KT WILL CONTINUE TO
BE OVER THE NORTHERN HALF OF THE LAKE WHICH IS CLOSER TO THE LOW AND
ITS TIGHT PRESSURE GRADIENT. THE LOWS COLD FRONT WILL SWEEP ACROSS
THE LAKE TONIGHT. WINDS WILL TURN OUT OF THE WEST AT 15 TO 25 KT
ACROSS THE LAKE BEHIND THE FRONT. HIGH PRESSURE MOVES IN BEHIND THE
FRONT TUESDAY NIGHT...WITH WINDS DIMINISHING AND BECOMING NORTHERLY
FOR A ON TUESDAY. THE LIGHT WINDS WILL CONTINUE TO VEER TO EASTERLY
AS THE HIGH MOVES OVER THE LAKE WEDNESDAY. WINDS TURN SOUTHEASTERLY
AS THE HIGH MAKES ITS WAY OVER NORTHERN QUEBEC ON THURSDAY.
ALTHOUGH THE CENTER OF THE HIGH MOVES OFF TO THE NORTHEAST...A LARGE
RIDGE WILL REMAIN OVER THE EASTERN THIRD OF THE US THROUGH THE
REMAINING PART OF THE FORECAST PERIOD. THIS PATTERN WILL RESULT IN
LIGHT WINDS VARYING BETWEEN EAST AND SOUTH.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
320 PM CDT MON JUN 11 2012
.DISCUSSION...
320 PM CDT
THE FORECAST CONCERNS ARE VERY MINIMAL THROUGH THE REST OF THE
WEEK WITH A CONTINUED DRY PATTERN. WILL BE MONITORING FOR A FEW
STORMS LATE THIS AFTERNOON INTO EARLY EVENING...OTHERWISE THAT MAY
WILL LIKELY BE ALL THAT IS ON THE SCOPE FOR QUITE A WHILE.
ISOLATED SHOWERS WITH A FEW STORMS REDEVELOPING OVER COOK COUNTY
AND SOUTH ALONG THE IL/IN STATE LINE...WHICH IS ALONG AND JUST
AHEAD OF A WEAK CONVERGENT AXIS AND APPARENT SHORT WAVE SEEN ON
SATELLITE. MID 80S TEMPERATURES AND UPPER 60S DEW POINTS ALONG AND
AHEAD OF THIS CORRIDOR HAS BUILT SURFACE BASED CAPE TO AROUND OR
SLIGHTLY OVER 2000 J/KG. THIS CONVECTION SHOULD LAST LONGER THAN
THE PREVIOUS ACTIVITY NEAR NOON BEING CLOSER TO THE SHORT WAVE
CENTER AND HAVING MORE INSTABILITY TO WORK WITH. UPPER LEVEL WIND
SHEAR LOOKS TO BE AROUND A MEAGER 20 KT PER PROFILER ANALYSIS. THE
BEHAVIOR OF THE STORM CORES IS LIKELY TO BE SOMEWHAT PULSY WITH
INSTABILITY IN THE DRIVERS SEAT...AND WITH LIMITED ATTENDANT SHEAR
IT LEAVES ONLY A VERY SMALL CHANCE FOR ANY TYPE OF SEVERE ACTIVITY.
THE SYSTEM UPPER TROUGH CENTER IS LOCATED ALONG THE MN/WESTERN
QUEBEC BORDER WITH PRIMARY HEIGHT FALLS...THE UPPER JET AXIS...AND
ASSOCIATED DEEPER ASCENT MOVING EAST FROM THERE. THIS FORCING HAS
AIDED SOME SHOWER DEVELOPMENT ALONG THE SURFACE COLD FRONT IN
WESTERN WI. THE COOL FRONT EXTENDS SOUTH FROM THERE WHERE IT WILL
MOVE INTO NW IL BY 4 PM AND EAST THROUGH THE FORECAST AREA THIS
EVE. THE WIND SHIFT IS GRADUAL FROM WEST SOUTHWEST TO WEST
NORTHWEST ALONG THE BOUNDARY...AND IT IS ACTUALLY AHEAD OF THE
STRONGEST MOISTURE CONVERGENCE. SO OVERALL CONVERGENCE IS LIMITED
AND FEEL THAT WILL BE THE CASE WITH ANY CONVECTION THAT WERE TO
TRIGGER ALONG IT...WHICH IS NOW APPEARING DOUBTFUL IN OUR AREA.
THE HRRR AND OTHER EXPLICIT CONVECTIVE MODELS AGREE IN THIS
LIMITED COVERAGE.
THE COOL FRONT WILL MOVE THROUGH THE AREA THIS EVENING AND IT
LOOKS LIKE THE BOUNDARY LAYER WILL STAY MIXED AS IT DOES
SUCH...WITH SOME GUSTS UP TO 20 MPH AS THE PRESSURE RISE AXIS
MOVES THROUGH. SUNNY AND DRY WEATHER WILL THEN ONCE AGAIN BE THE
STORY AS CANADIAN HIGH PRESSURE MOVES OVERHEAD TUESDAY NIGHT INTO
WEDNESDAY. THE REALLY ONLY WEATHER OF INTEREST FROM DAY TO DAY WILL
BE HOW LOW DEW POINTS WILL DROP DURING THE AFTERNOON MIXING...AND
TO WHAT DEGREE OF COOLING WILL THERE BE FROM THE LAKE. NORTHWEST
WINDS WILL BEGIN TO DECREASE TUESDAY AFTERNOON...POTENTIALLY
ALLOWING FOR A SLIGHT LAKE BREEZE INTO IL...BUT LIKELY INTO IN.
THIS MAY NOT DEVELOP UNTIL LATE AFTERNOON THOUGH...SO WIDESPREAD
HIGHS IN THE MID TO UPPER 70S ARE EXPECTED. UPSTREAM DEW POINTS
TODAY HAVE BEEN IN THE LOWER TO MID 40S ACROSS EASTERN SD. THIS
AND POSSIBLY EVEN LOWER SHOULD BE REALIZED DURING TUESDAY AFTERNOON
WITH PROJECTED MIXING TO 850 MB. THE AFTERNOON HUMIDITY WILL
REMAIN LOW...UNDER 25 PERCENT...ON WEDNESDAY AFTERNOON WITH THE
SYNOPTIC FLOW TURNING NORTHEAST AND THEN EAST.
INFLUENCE FROM THE LAKE WILL LIKELY CONTINUE TO MOVE INTO CHICAGO
DURING THE AFTERNOON ALL THE WAY THROUGH SATURDAY. THE UPPER LEVEL
HEIGHTS AND LOW-LEVEL THERMAL RIDGE BUILD MORE INTO THE AREA
THURSDAY NIGHT INTO SATURDAY. THE EC HAS SHOWN IN THE UPPER LEVEL
SW FLOW THAT SHORT WAVE ENERGY IS POSSIBLE WITHIN THIS AND MAY
DAMPEN THE RIDGE SLIGHTLY SATURDAY NIGHT INTO SUNDAY...AND HAVE A
SMALL CHANCE FOR POPS DURING PART OF THAT TIME. OTHERWISE...HAVE
COLLABORATED GOING DRIER THAN POPS AND DEW POINTS FROM GUIDANCE
BLENDS IN THE EXTENDED PER PERSISTENCE AND AN OVERALL STAGNANT
PATTERN.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* WINDS SHIFTING FROM SW THIS AFTERNOON TO NW THIS
EVENING...POTENTIAL FOR GUSTINESS TO CONTINUE OVERNIGHT.
* COUPLE WINDOWS OF POTENTIAL FOR ADDITIONAL THUNDERSTORM
DEVELOPMENT THIS AFTERNOON AND AGAIN THIS EVENING.
RC
//DISCUSSION...UPDATED 20Z...
STILL DO NOT THINK TSRA WILL DIRECTLY IMPACT ORD/MDW THE NEXT FEW
HOURS AND PROBABILITY OF REDEVELOPMENT AHEAD OF FRONT THIS EVENING
IS LOW. VCTS NEAR GYY SHOULD REMAIN SOUTHEAST OF GYY. WILL MONITOR
POTENTIAL FOR POP-UP DEVELOPMENT THE NEXT FEW HOURS. OTHER CHANGE
IN 20Z AMD WAS TO MOVE UP TIMING OF WIND SHIFT TO NORTHWEST BY 1
HOUR EARLIER AT TAF SITES. THIS MAY NEED TO BE MOVED UP A BIT
MORE. POTENTIAL FOR NW WIND GUSTS AFTER FRONTAL PASSAGE
EXISTS...BUT NOT ENOUGH CONFIDENCE TO INCLUDE IN TAF.
RC
...FROM 18Z...
A COLD FRONT LIES ACROSS NORTHWEST WISCONSIN SOUTH INTO CENTRAL IOWA
THIS AFTERNOON. ONGOING THUNDERSTORMS CONTINUE ACROSS PORTIONS
SOUTHERN MISSOURI INTO CENTRAL ILLINOIS PROVIDING A CANOPY OF CLOUD
COVER ACROSS MUCH OF NORTHERN ILLINOIS THIS AFTERNOON. THERE IS SOME
CLEARING ACROSS PORTIONS OF EAST CENTRAL ILLINOIS AND NORTHWEST
INDIANA WHERE AN AXIS OF MODEST INSTABILITY HAS BEGUN TO DEVELOP. AN
UPPER LEVEL DISTURBANCE MOVING ACROSS IOWA EARLY THIS AFTERNOON WILL
PUSH EAST ACROSS NORTHERN ILLINOIS WITH THE POTENTIAL FOR ADDITIONAL
THUNDERSTORM DEVELOPMENT ACROSS THIS INSTABILITY AXIS MID AFTERNOON.
IT APPEARS THE THREAT SHOULD STAY SOUTHEAST/EAST OF ORD/MDW WITH
SOME POTENTIAL FOR GYY TO BE IMPACTED OR AT LEAST TO SEE ACTIVITY IN
THE VICINITY OF THE TERMINAL. MOVED UP VCTS AT GYY TO START OF TAF
GIVEN ACTIVITY CURRENTLY IN THE AREA JUST NORTHWEST OF THE
TERMINAL AT 18Z. LATE THIS EVENING...THE COLD FRONT IS EXPECTED TO
MOVE ACROSS THE AREA WITH WINDS BECOMING NORTHWEST. THERE MAY BE
ADDITIONAL THUNDERSTORMS THAT DEVELOP ALONG THE FRONT...BUT GIVEN
THE WEAK CONVERGENCE ALONG THE FRONT AND LOSS OF DIURNAL
HEATING...EXPECT COVERAGE TO BE ISOLATED TO WIDELY SCATTERED WITH
LOW THREAT OF BEING ON STATION. ON TUESDAY...HIGH PRESSURE WILL
BEGIN TO BUILD IN FROM THE NORTHWEST. WILL HAVE TO MONITOR THE
POSSIBILITY OF A LAKE BREEZE TURNING WINDS NORTHEAST IN THE
CHICAGO AREA LATE IN THE AFTERNOON.
BMD/RC
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM TO HIGH CONFIDENCE IN WIND DIRECTION...LOW CONFIDENCE IN
WIND GUST MAGNITUDE...PARTICULARLY THIS EVENING BEHIND THE
FRONT.
* MEDIUM CONFIDENCE IN TSRA SE OF THE TERMINALS THIS AFTERNOON...LOW
CONFIDENCE IT WILL IMPACT ORD/MDW.
* LOW CONFIDENCE IN TSRA ALONG THE FRONT THIS EVENING.
RC
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT THROUGH SATURDAY...VFR.
SUNDAY...VFR. SLIGHT CHC SHRA/TSRA.
BEACHLER
&&
.MARINE...
231 PM CDT
A LARGE LOW HAS MOVED INTO HUDSON BAY...WHILE HIGH PRESSURE SITS OFF
THE NEW ENGLAND COAST. THE UPPER LEVEL PRESSURE GRADIENT HAS
RELAXED...RESULTING IN SOUTH TO SOUTHWEST WINDS 15-25 KT ACROSS THE
LAKE THIS AFTERNOON. STRONGEST WINDS AROUND 25 KT WILL CONTINUE TO
BE OVER THE NORTHERN HALF OF THE LAKE WHICH IS CLOSER TO THE LOW AND
ITS TIGHT PRESSURE GRADIENT. THE LOWS COLD FRONT WILL SWEEP ACROSS
THE LAKE TONIGHT. WINDS WILL TURN OUT OF THE WEST AT 15 TO 25 KT
ACROSS THE LAKE BEHIND THE FRONT. HIGH PRESSURE MOVES IN BEHIND THE
FRONT TUESDAY NIGHT...WITH WINDS DIMINISHING AND BECOMING NORTHERLY
FOR A ON TUESDAY. THE LIGHT WINDS WILL CONTINUE TO VEER TO EASTERLY
AS THE HIGH MOVES OVER THE LAKE WEDNESDAY. WINDS TURN SOUTHEASTERLY
AS THE HIGH MAKES ITS WAY OVER NORTHERN QUEBEC ON THURSDAY.
ALTHOUGH THE CENTER OF THE HIGH MOVES OFF TO THE NORTHEAST...A LARGE
RIDGE WILL REMAIN OVER THE EASTERN THIRD OF THE US THROUGH THE
REMAINING PART OF THE FORECAST PERIOD. THIS PATTERN WILL RESULT IN
LIGHT WINDS VARYING BETWEEN EAST AND SOUTH.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
258 PM CDT MON JUN 11 2012
.DISCUSSION...
ISSUED 258 PM CDT MON JUN 11 2012
SHORT TERM...TONIGHT THROUGH THURSDAY
MAIN QUESTION IN THE IMMEDIATE SHORT-TERM IS WHETHER OR NOT ANY
CONVECTION WILL RE-DEVELOP ALONG AN ADVANCING COLD FRONT THIS
EVENING. 2 PM SURFACE ANALYSIS SHOWS FRONT ACROSS EASTERN
IOWA...HOWEVER AIRMASS AHEAD OF IT IS STILL QUITE STABLE DUE TO
MORNING CONVECTION THAT DECAYED ACROSS WEST-CENTRAL ILLINOIS.
LATEST MESO-ANALYSIS FROM SPC IS INDICATING SOME DESTABILIZATION
ALONG THE BOUNDARY...WITH SURFACE-BASED CAPES BACK UP TO AROUND
1500 TO 2000J/KG. 19Z VISIBLE SATELLITE IMAGERY IS SHOWING A
NARROW RIBBON OF CU DEVELOPING IN THE INSTABILITY AXIS...HOWEVER
NO SHOWERS/STORMS HAVE FIRED YET. 12Z MODELS ARE LARGELY
USELESS...AS NONE OF THEM ADEQUATELY PREDICTED THE STORMS THAT
ROLLED ACROSS SOUTH-CENTRAL AND SOUTHEAST ILLINOIS THIS AFTERNOON
ALONG THE LEADING EDGE OF AN OLD OUTFLOW BOUNDARY. EVEN SOME OF
THE HIGHER-RES MODELS SUCH AS THE 4KM WRF FAILED TO CAPTURE THIS
CONVECTION...SO THEIR SOLUTIONS FOR LATE THIS AFTERNOON AND
EVENING ARE SUSPECT. THE 17Z HRRR SEEMS TO HAVE THE BEST HANDLE ON
REALITY...SHOWING THE CURRENT CONVECTION ACROSS THE FAR E/SE KILX
CWA EXITING THE AREA OVER THE NEXT 2 TO 3 HOURS...FOLLOWED BY
LARGELY DRY CONDITIONS THIS EVENING. THE HRRR DOES TRY TO DEVELOP
SOME ISOLATED CONVECTION ALONG THE COLD FRONT AS IT PUSHES INTO
THE ILLINOIS RIVER VALLEY AROUND 00Z...BUT THIS RAPIDLY DISSIPATES
AS DAYTIME INSTABILITY IS LOST AFTER SUNSET. SINCE THE FRONT IS
STILL OFF TO THE WEST...THINK THIS SOLUTION SEEMS REASONABLE...SO
WILL MENTION ISOLATED THUNDER ACROSS THE BOARD DURING THE EARLY
EVENING. AFTER THAT...SKIES WILL CLEAR FROM WEST TO EAST ACROSS
THE AREA AS THE FRONT PUSHES INTO INDIANA AFTER MIDNIGHT.
HIGH PRESSURE WILL BUILD INTO THE GREAT LAKES FOR THE MIDDLE OF
THE WEEK...PROVIDING COOLER AND LESS HUMID CONDITIONS FOR TUESDAY
THROUGH THURSDAY. COOLEST MORNING WILL BE WEDNESDAY MORNING...WHEN
TEMPS FALL INTO THE LOWER 50S. AFTERNOON HIGHS ON WEDNESDAY WILL
BE NEAR OR SLIGHTLY BELOW NORMAL IN THE UPPER 70S/LOWER 80S.
LONG TERM...FRIDAY THROUGH MONDAY
WARMER AND MORE HUMID WEATHER WILL RETURN FOR THE EXTENDED...AS
UPPER TROUGH DIGS ACROSS THE WESTERN CONUS AND RIDGING DEVELOPS
ACROSS THE EAST. MODELS CONTINUE TO DISAGREE ON THE EXACT DEGREE
OF AMPLIFICATION WITHIN THE FLOW...WITH THE 12Z 11 JUN GFS
FEATURING A STRONG RIDGE AND RESULTING DRY CONDITIONS RIGHT
THROUGH EARLY NEXT WEEK. MEANWHILE...THE LATEST ECMWF CONTINUES TO
BE WEAKER WITH THE UPPER RIDGE AND BRINGS A FRONTAL BOUNDARY INTO
THE AREA SUNDAY INTO MONDAY. GIVEN CURRENT MODEL DISCREPANCIES
AND THE FACT THAT PARTS OF CENTRAL ILLINOIS ARE IN A MODERATE
DROUGHT...WILL MAINTAIN HOT AND DRY CONDITIONS THROUGH MONDAY.
BARNES
&&
.AVIATION...
ISSUED 1255 PM CDT MON JUN 11 2012
LINE OF STRONG THUNDERSTORMS ALONG I-57 ON LEADING EDGE OF MCS AT
CMI JUST GOT A NW WIND GUST OF 35 KTS WITH HEAVY RAINS TO REDUCE
VSBY TO 1/2-1 MILE DURING THE NEXT HOUR OR SO AS LINE MOVES
STEADILY EASTWARD. MVFR CEILINGS LIKELY AS WELL AT CMI. NO
REPORTS OF HAIL YET AND THINK BETTER HAIL THREAT WILL BE SOUTH OF
CMI. HAVE TS WITH MVFR CEILINGS AND VSBY AT DEC NEXT HOUR WHILE
CONVECTION APPEARS TO BE EAST OF I-55/REST OF CENTRAL IL TAF SITES
THIS AFTERNOON. COULD STILL BE ISOLATED CONVECTION THIS AFTERNOON
AS COLD FRONT IN SE IA INTO CENTRAL MO TRACKS SE INTO SE IL EARLY
THIS EVENING. SKIES TO CLEAR LATER THIS EVENING AND CONTINUE
THROUGH TUE AS 1026 MB HIGH PRESSURE OVER THE NORTHERN ROCKIES
SETTLES INTO THE MIDWEST BY 18Z/TUE. SSW WINDS 10-15 KTS WITH
POSSIBLE WIND GUSTS NEAR 20 KTS TO TURN NW BEHIND THE FRONT AND
DIMINISH TO 5-10 KTS THEN BE NW 10-15 KTS TUESDAY WITH GUSTS TO 20
KTS BY MIDDAY TUE.
HUETTL
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
301 AM CDT MON JUN 11 2012
.DISCUSSION...
929 PM CDT
SOME MINOR CHANGES MADE TO ARRIVAL TIMING OF POPS FOR MONDAY
MORNING...OTHERWISE NO REAL CHANGES MADE TO GOING FORECAST FOR
TONIGHT INTO MONDAY.
EXPANSIVE UPPER LEVEL LOW AND ASSOCIATED HIGH PWAT AIR...AS SEEN
ON WATER VAPOR...IS EXPANDING NORTHWARD. A WEAK UPPER LEVEL WAVE
IN SOUTHWEST IL THIS EVE HAS HELPED TO SPREAD THIS NORTH CAUSING
AN EXPANSION IN HIGH CLOUDS ACROSS THE AREA...WHICH SHOULD
CONTINUE INTO OVERNIGHT. THESE CLOUDS ALONG WITH SOUTHERLY FLOW
REMAINING AROUND 10 MPH TONIGHT SHOULD KEEP MINIMUM TEMPERATURES 3
TO 5 DEGREES WARMER THAN LAST NIGHT...WHICH IS RIGHT ON PAR WITH
GOING FORECAST. LIGHT RETURNS ON THE KIND RADAR ARE INDICATIVE OF
GRADUAL MID-LEVEL ASCENT AND SATURATION OCCURRING AHEAD OF THIS
UPPER LOW. SATELLITE TRENDS AND GUIDANCE FORECASTS KEEP ALMOST ALL
OF THIS ENTIRELY EAST OF THE AREA LATER TONIGHT INTO MONDAY
MORNING.
THE FEATURE WHICH WILL HAVE MORE INFLUENCE ON THE AREA IS A WELL-
DEFINED UPPER LEVEL TROUGH ACROSS THE CANADIAN/U.S. HIGH PLAINS
BORDER. IMPRESSIVE NORTH-TO-SOUTH LINE OF CONVECTION FROM NEAR
INTERNATIONAL FALLS TO NORTHEAST KS HAS DEVELOPED JUST AHEAD OF
THE SURFACE COOL FRONT WHERE CONVERGENCE WAS MAXIMIZED AND WITHIN
A CORRIDOR OF HIGHER THETA-E RETURN. THE FRONT AND CONVECTION
AHEAD OF IT WILL EVOLVE EAST INTO OVERNIGHT...LIKELY GRADUALLY
TAPERING IN INTENSITY AND AT LEAST SOMEWHAT IN COVERAGE OVERNIGHT
ACROSS IA AND NORTHERN MO. A PORTION OF THIS MAY MAKE IT INTO THE
WESTERN FORECAST AREA IN THE EARLY MORNING...AND THE HRRR SOLUTION
DEPICTS THIS...HOWEVER IT SEEMS TOO GENEROUS ON DEVELOPMENT
OVERNIGHT IN THE ABSENCE OF MUCH OF A LOW-LEVEL JET/WAA.
THE MID-LEVEL SHORT WAVE AXIS ACROSS EASTERN NE AND KS HELPING TO
DRIVE SOME OF THE CONVECTION IS DEPICTED IN MOST GUIDANCE...AND
TRACKS ACROSS THE FORECAST AREA DURING THE LATE MORNING AND
AFTERNOON. COLLOCATED WITH THIS APPEARS TO BE A PRE-FRONTAL
TROUGH...AT LEAST IN THE 925-700MB FLOW...WHICH HELPS IN FOCUSING
SOME OF THE CONVERGENCE FIELDS. INSTABILITY VALUES ARE SIMILAR ON
THE 11.00 NAM TO THOSE MENTIONED IN PRIOR DISCUSSION...SO SOME
SCATTERED CONVECTION REGENERATING IN COVERAGE DURING THE MIDDAY
TIME IS FAVORED AT THIS TIME. HAVE ADJUSTED MORNING POPS TO
ACCOUNT FOR THIS TYPE OF TIMING/REASONING. AFTERNOON POPS STILL
LOOK GOOD.
MTF
//PREV DISCUSSION...
317 PM CDT
FOCUS OF FORECAST IS ON RAIN CHANCES MON AND MON EVE WITH A COLD
FRONT MOVING ACROSS THE AREA...AND THEN ON THE VERY LOW...IF
ANY...PROBABILITIES FOR RAIN THROUGH THE REST OF THE WORK WEEK AND
WELL INTO NEXT WEEKEND.
AN UPPER LOW OVER SOUTHERN SASKATCHEWAN AND NORTHEASTERN MT HAS
CONTINUED TO BECOME SHEARED/ELONGATED TODAY...SLOWING ITS EASTWARD
PROGRESS. AS A RESULT THE ASSOCIATED SURFACE LOW AND ATTENDANT COLD
FRONT HAVE ALSO BEEN RELUCTANT TO MOVE EASTWARD WITH ANY VIGOR.
MODELS SHOW THE UPPER LOW IS TO ACCELERATE NORTHEASTWARD LATER TODAY
AND TONIGHT AS A SHORT WAVE AND JET MAX DIG SSE FROM THE YUKON-NW
TERRITORIES BORDER TO SOUTHERN SASKATCHEWAN AND NE MT BY 12Z MON.
THIS SHORT WAVE AND SPEED MAX ARE THEN PROGGED TO TURN SOUTHEASTERLY
ACROSS THE DAKOTAS AND MN DURING THE DAY MON. WITH THE UPPER TROUGH
BECOMING MORE PROGRESSIVE THE COLD FRONT...WHICH IS CURRENTLY
LINGERING ACROSS NW AND W CENTRAL MN AND FAR SE SD AND NE NE...
WILL ALSO START TO ACCELERATE EASTWARD...REACHING THE MID MS VALLEY
BY EARLY MON AFTERNOON AND CONTINUING TO SE WI AND NE IL EARLY MON
EVENING. CONVERGENCE ALONG THE COLD FRONT AS IT MOVES ACROSS THE
LOCAL FORECAST AREA IS NOT VERY STRONG THOUGH TIMING OF THE FRONTAL
PASSAGE DURING OR SOON AFTER PEAK HEATING LEADS TO IT OCCURRING WHEN
INSTABILITY WILL BE MAXIMIZED WITH DEW POINTS SLOWLY CREEPING UP
INTO THE 60S OVERNIGHT AND MON.
HOWEVER...IF 10.12Z RUN OF GFS VERIFIES WITH THE LAYER FROM 2 TO 4K
FT AGL SOME 3-4 DEG C WARMER THAN THE NAM SOLUTION DURING THE DAY
MON THEN CONVECTIVE DEVELOPMENT AHEAD OF THE COLD FRONT WILL BE
INHIBITED BY THE WARMTH ALOFT MAINTAINING A SIGNIFICANT AREA OF CIN
AND CAPPING AT LEAST THROUGH 18Z MON. NAM HAS MINIMAL CIN AHEAD OF
THE FRONT BUT THE QPF AND MOS POP VALUES ARE FLIPPED FROM WHAT ONE
WOULD EXPECT GIVEN THE DIFFERENCES IN THE FORECAST SOUNDINGS. THAT
IS...THE GFS IS MORE GENEROUS WITH THE QPF WHILE THE NAM GENERATES
SOME SMALL RAINFALL AMOUNTS INTO N CENTRAL IL BOTH ONLY A FEW
HUNDREDTHS AT MOST ACROSS THE REST OF THE FA...WITH MOS POPS IN
LOWER END OF CHANCE CATEGORY AND GFS AT HIGH END. HAVE LOWERED POPS
SLIGHTLY FOR MON THOUGH STILL LEFT AT VERY LOW END OF LIKELY WITH
55-60 PCT ACROSS THE FA.
ZONAL FLOW SPREADS EASTWARD ACROSS THE ROCKIES AND GREAT PLAINS
BY TUE...AND ACROSS THE MIDWEST AND GREAT LAKES BY WED BRINGING
MILDER AND DRY AIR TO THE REGION. MODELS INDICATE A MINOR SHORT WAVE
TO TRAVERSE THE DAKOTAS TUE NIGHT AND WED...AND THE UPPER MIDWEST
WED NIGHT AND THU. THE SURFACE RIDGE THAT WILL BUILD IN BEHIND THE
COLD FRONT IS PROGGED TO STILL HAVE ITS AXIS FROM QUEBEC SW BACK
ACROSS THE GREAT LAKES AND TO THE MID MS VALLEY. THIS WOULD PLACE
ANY THREAT OF RAIN WITH THIS DISTURBANCE TO THE N OF THE FA.
UPPER RIDGING TO PUSH BACK NORTHEASTWARD ACROSS THE MIDWEST AND
GREAT LAKES THU AND FRI AS AN UPPER TROUGH DEEPENS OVER FAR WESTERN
NOAM. AFTER MAX TEMPS COOL TO THE 70S FOR A COUPLE DAYS AFTER THE
COLD FRONTAL PASSAGE THEY CLIMB BACK INTO THE MID AND UPPER 80S FOR
FRI AND NEXT WEEKEND WITH THE UPPER RIDGE BUILDING OVERHEAD. AREAS
NEAR THE LAKE WILL BE COOLER FROM TUE INTO NEXT WEEKEND AS THE
SURFACE HIGH BUILDING INTO THE REGION ALLOWS NNE FLOW TO TURN IN
OFF OF THE LAKE TUE AND THEN WITH THE CENTER OF THE ANTICYCLONE
MOVING OVER THE CENTRAL GREAT LAKES PROVIDES E TO SE LOW LEVEL FLOW
OFF OF THE LAKE FROM WED ON. RIDGING SURFACE AND ALOFT TO KEEP AREA
RAIN-FREE TUE THROUGH SAT...WITH ONLY SLIGHT CHANCES IN N CENTRAL IL
ON SUN.
WITH THE AREA NOT SEEING ANY LET ALONE SIGNIFICANT RAINFALL SINCE
THE END OF MAY ANY AREAS THAT DO NOT GET ANY SIGNIFICANT RAIN WITH
COLD FRONT WILL SEE MUCH GREATER MOISTURE DEFICITS AS NO ADDITIONAL
THREAT OF SIGNIFICANT RAINS UNTIL AT LEAST LATE NEXT WEEKEND OR
EARLY NEXT WORK WEEK.
TRS
&&
.FIRE WEATHER...
317 PM CDT
WINDS AND RH VALUES APPROACHING BUT NOT EXPECTED TO REACH RED
FLAG CRITERIA THE REST OF THE AFTERNOON OR EARLY THIS EVENING.
TRS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* NO IMPACTS THROUGH 12Z.
* TSRA POTENTIAL IN THE AFTERNOON HOURS.
BEACHLER
//DISCUSSION...UPDATED 06Z...
LOW LEVEL HIGH PRESSURE HAS PUSHED FURTHER EAST OF THE
REGION...ALLOWING A CONTINUED FEED OF SOUTHERLY WINDS OVER
NORTHERN IL/NORTHWEST IN AIRFIELDS. A COLD FRONTAL BOUNDARY
REMAINS WEST OF THE REGION...HOWEVER WILL CONTINUE TO SLOWLY PUSH
EAST THROUGHOUT THE DAY TODAY. FRONTAL PASSAGE IS EXPECTED TO
OCCUR DURING THE LATE AFTN/EVE HOURS. THEN WINDS VEER
WEST/NORTHWEST DURING THE EVENING AND OVERNIGHT HOURS INTO TUE.
THE OTHER CONCERN IS IN REGARDS TO TSRA DEVELOPMENT. GUIDANCE HAS
STRUGGLED WITH THE PRECISE TIMING/PLACEMENT/INTENSITY...AND MANY
THINGS STILL NEED TO COME TOGETHER. AT THIS TIME THE BEST TIMING
IS FOR SHRA/TSRA DEVELOPMENT TO OCCUR DURING THE AFTN/EVE
HOURS...THEN PUSH EAST INTO NORTHERN IN. AT THIS TIME GIVEN THE
LOW CONFIDENCE HAVE MAINTAINED THE PROB30 GROUP...AND WILL ALLOW
FOR FURTHER ADJUSTMENTS AS WE APPROACH THE LATE MORNING HOURS.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE IN ALL ELEMENTS THROUGH 16Z.
* MEDIUM CONFIDENCE ON TSRA DEVELOPMENT AFT 16Z.
* LOW CONFIDENCE ON COVERAGE OF TSRA.
* HIGH CONFIDENCE IN WIND DIR/SPEED FORECAST.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...
TUESDAY THROUGH SATURDAY...VFR.
RATZER
&&
.MARINE...
300 AM CDT
SURFACE HIGH PRESSURE CENTERED OVER THE SOUTHEAST COASTAL UNITED
STATES WILL CONTINUE TO PUSH EAST...WHILE AN UPPER LEVEL TROUGH OF
LOW PRESSURE PUSHES EAST ACROSS THE UPPER MIDWEST. ASSOCIATED WITH
THE UPPER LEVEL SYSTEM WAS A COUPLE OF SURFACE LOW PRESSURES OVER
CENTRAL AND SOUTHWEST ONTARIO. THESE LOW PRESSURE SYSTEMS WILL
CONSOLIDATE ALLOWING FOR A TIGHTENING GRADIENT ALONG THE NORTHERN
PORTION OF LAKE MICHIGAN FOR THE FIRST HALF OF TODAY...THEN THE
GRADIENT WILL BEGIN TO SLACKEN MARGINALLY. SOUTHERLY FLOW WILL
DOMINATE THE LAKE FOR TODAY...THEN AS A FRONTAL BOUNDARY SLOWLY
APPROACHES FROM THE WEST WINDS WILL BEGIN TO TURN SOUTHWESTERLY.
FRONTAL PASSAGE WILL BRING WEST AND EVENTUALLY NORTHWEST WINDS
ACROSS THE LAKE. THE LOW PRESSURE SYSTEM OVER SOUTHERN HUDSON BAY
WILL THEN DEEPEN...ALLOWING FOR AN INCREASED GRADIENT TO OCCUR
ACROSS THE NORTHERN LAKES AND MAY STRETCH SOUTH ACROSS LAKE MICHIGAN
TUE. OVERALL EXPECT WINDS TUE FROM A NORTHWEST/NORTH WIND TO BE 15
TO 25 KT. BROAD HIGH PRESSURE THEN BUILDS INTO THE GREAT LAKES
REGION AND WILL PROVIDE MUCH LIGHTER WINDS FOR THE TUE NGT THROUGH
THUR PERIODS. WINDS WILL MAINLY BE NORTH/NORTHEAST DURING THESE
PERIODS.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
101 AM CDT MON JUN 11 2012
.DISCUSSION...
929 PM CDT
SOME MINOR CHANGES MADE TO ARRIVAL TIMING OF POPS FOR MONDAY
MORNING...OTHERWISE NO REAL CHANGES MADE TO GOING FORECAST FOR
TONIGHT INTO MONDAY.
EXPANSIVE UPPER LEVEL LOW AND ASSOCIATED HIGH PWAT AIR...AS SEEN
ON WATER VAPOR...IS EXPANDING NORTHWARD. A WEAK UPPER LEVEL WAVE
IN SOUTHWEST IL THIS EVE HAS HELPED TO SPREAD THIS NORTH CAUSING
AN EXPANSION IN HIGH CLOUDS ACROSS THE AREA...WHICH SHOULD
CONTINUE INTO OVERNIGHT. THESE CLOUDS ALONG WITH SOUTHERLY FLOW
REMAINING AROUND 10 MPH TONIGHT SHOULD KEEP MINIMUM TEMPERATURES 3
TO 5 DEGREES WARMER THAN LAST NIGHT...WHICH IS RIGHT ON PAR WITH
GOING FORECAST. LIGHT RETURNS ON THE KIND RADAR ARE INDICATIVE OF
GRADUAL MID-LEVEL ASCENT AND SATURATION OCCURRING AHEAD OF THIS
UPPER LOW. SATELLITE TRENDS AND GUIDANCE FORECASTS KEEP ALMOST ALL
OF THIS ENTIRELY EAST OF THE AREA LATER TONIGHT INTO MONDAY
MORNING.
THE FEATURE WHICH WILL HAVE MORE INFLUENCE ON THE AREA IS A WELL-
DEFINED UPPER LEVEL TROUGH ACROSS THE CANADIAN/U.S. HIGH PLAINS
BORDER. IMPRESSIVE NORTH-TO-SOUTH LINE OF CONVECTION FROM NEAR
INTERNATIONAL FALLS TO NORTHEAST KS HAS DEVELOPED JUST AHEAD OF
THE SURFACE COOL FRONT WHERE CONVERGENCE WAS MAXIMIZED AND WITHIN
A CORRIDOR OF HIGHER THETA-E RETURN. THE FRONT AND CONVECTION
AHEAD OF IT WILL EVOLVE EAST INTO OVERNIGHT...LIKELY GRADUALLY
TAPERING IN INTENSITY AND AT LEAST SOMEWHAT IN COVERAGE OVERNIGHT
ACROSS IA AND NORTHERN MO. A PORTION OF THIS MAY MAKE IT INTO THE
WESTERN FORECAST AREA IN THE EARLY MORNING...AND THE HRRR SOLUTION
DEPICTS THIS...HOWEVER IT SEEMS TOO GENEROUS ON DEVELOPMENT
OVERNIGHT IN THE ABSENCE OF MUCH OF A LOW-LEVEL JET/WAA.
THE MID-LEVEL SHORT WAVE AXIS ACROSS EASTERN NE AND KS HELPING TO
DRIVE SOME OF THE CONVECTION IS DEPICTED IN MOST GUIDANCE...AND
TRACKS ACROSS THE FORECAST AREA DURING THE LATE MORNING AND
AFTERNOON. COLLOCATED WITH THIS APPEARS TO BE A PRE-FRONTAL
TROUGH...AT LEAST IN THE 925-700MB FLOW...WHICH HELPS IN FOCUSING
SOME OF THE CONVERGENCE FIELDS. INSTABILITY VALUES ARE SIMILAR ON
THE 11.00 NAM TO THOSE MENTIONED IN PRIOR DISCUSSION...SO SOME
SCATTERED CONVECTION REGENERATING IN COVERAGE DURING THE MIDDAY
TIME IS FAVORED AT THIS TIME. HAVE ADJUSTED MORNING POPS TO
ACCOUNT FOR THIS TYPE OF TIMING/REASONING. AFTERNOON POPS STILL
LOOK GOOD.
MTF
//PREV DISCUSSION...
317 PM CDT
FOCUS OF FORECAST IS ON RAIN CHANCES MON AND MON EVE WITH A COLD
FRONT MOVING ACROSS THE AREA...AND THEN ON THE VERY LOW...IF
ANY...PROBABILITIES FOR RAIN THROUGH THE REST OF THE WORK WEEK AND
WELL INTO NEXT WEEKEND.
AN UPPER LOW OVER SOUTHERN SASKATCHEWAN AND NORTHEASTERN MT HAS
CONTINUED TO BECOME SHEARED/ELONGATED TODAY...SLOWING ITS EASTWARD
PROGRESS. AS A RESULT THE ASSOCIATED SURFACE LOW AND ATTENDANT COLD
FRONT HAVE ALSO BEEN RELUCTANT TO MOVE EASTWARD WITH ANY VIGOR.
MODELS SHOW THE UPPER LOW IS TO ACCELERATE NORTHEASTWARD LATER TODAY
AND TONIGHT AS A SHORT WAVE AND JET MAX DIG SSE FROM THE YUKON-NW
TERRITORIES BORDER TO SOUTHERN SASKATCHEWAN AND NE MT BY 12Z MON.
THIS SHORT WAVE AND SPEED MAX ARE THEN PROGGED TO TURN SOUTHEASTERLY
ACROSS THE DAKOTAS AND MN DURING THE DAY MON. WITH THE UPPER TROUGH
BECOMING MORE PROGRESSIVE THE COLD FRONT...WHICH IS CURRENTLY
LINGERING ACROSS NW AND W CENTRAL MN AND FAR SE SD AND NE NE...
WILL ALSO START TO ACCELERATE EASTWARD...REACHING THE MID MS VALLEY
BY EARLY MON AFTERNOON AND CONTINUING TO SE WI AND NE IL EARLY MON
EVENING. CONVERGENCE ALONG THE COLD FRONT AS IT MOVES ACROSS THE
LOCAL FORECAST AREA IS NOT VERY STRONG THOUGH TIMING OF THE FRONTAL
PASSAGE DURING OR SOON AFTER PEAK HEATING LEADS TO IT OCCURRING WHEN
INSTABILITY WILL BE MAXIMIZED WITH DEW POINTS SLOWLY CREEPING UP
INTO THE 60S OVERNIGHT AND MON.
HOWEVER...IF 10.12Z RUN OF GFS VERIFIES WITH THE LAYER FROM 2 TO 4K
FT AGL SOME 3-4 DEG C WARMER THAN THE NAM SOLUTION DURING THE DAY
MON THEN CONVECTIVE DEVELOPMENT AHEAD OF THE COLD FRONT WILL BE
INHIBITED BY THE WARMTH ALOFT MAINTAINING A SIGNIFICANT AREA OF CIN
AND CAPPING AT LEAST THROUGH 18Z MON. NAM HAS MINIMAL CIN AHEAD OF
THE FRONT BUT THE QPF AND MOS POP VALUES ARE FLIPPED FROM WHAT ONE
WOULD EXPECT GIVEN THE DIFFERENCES IN THE FORECAST SOUNDINGS. THAT
IS...THE GFS IS MORE GENEROUS WITH THE QPF WHILE THE NAM GENERATES
SOME SMALL RAINFALL AMOUNTS INTO N CENTRAL IL BOTH ONLY A FEW
HUNDREDTHS AT MOST ACROSS THE REST OF THE FA...WITH MOS POPS IN
LOWER END OF CHANCE CATEGORY AND GFS AT HIGH END. HAVE LOWERED POPS
SLIGHTLY FOR MON THOUGH STILL LEFT AT VERY LOW END OF LIKELY WITH
55-60 PCT ACROSS THE FA.
ZONAL FLOW SPREADS EASTWARD ACROSS THE ROCKIES AND GREAT PLAINS
BY TUE...AND ACROSS THE MIDWEST AND GREAT LAKES BY WED BRINGING
MILDER AND DRY AIR TO THE REGION. MODELS INDICATE A MINOR SHORT WAVE
TO TRAVERSE THE DAKOTAS TUE NIGHT AND WED...AND THE UPPER MIDWEST
WED NIGHT AND THU. THE SURFACE RIDGE THAT WILL BUILD IN BEHIND THE
COLD FRONT IS PROGGED TO STILL HAVE ITS AXIS FROM QUEBEC SW BACK
ACROSS THE GREAT LAKES AND TO THE MID MS VALLEY. THIS WOULD PLACE
ANY THREAT OF RAIN WITH THIS DISTURBANCE TO THE N OF THE FA.
UPPER RIDGING TO PUSH BACK NORTHEASTWARD ACROSS THE MIDWEST AND
GREAT LAKES THU AND FRI AS AN UPPER TROUGH DEEPENS OVER FAR WESTERN
NOAM. AFTER MAX TEMPS COOL TO THE 70S FOR A COUPLE DAYS AFTER THE
COLD FRONTAL PASSAGE THEY CLIMB BACK INTO THE MID AND UPPER 80S FOR
FRI AND NEXT WEEKEND WITH THE UPPER RIDGE BUILDING OVERHEAD. AREAS
NEAR THE LAKE WILL BE COOLER FROM TUE INTO NEXT WEEKEND AS THE
SURFACE HIGH BUILDING INTO THE REGION ALLOWS NNE FLOW TO TURN IN
OFF OF THE LAKE TUE AND THEN WITH THE CENTER OF THE ANTICYCLONE
MOVING OVER THE CENTRAL GREAT LAKES PROVIDES E TO SE LOW LEVEL FLOW
OFF OF THE LAKE FROM WED ON. RIDGING SURFACE AND ALOFT TO KEEP AREA
RAIN-FREE TUE THROUGH SAT...WITH ONLY SLIGHT CHANCES IN N CENTRAL IL
ON SUN.
WITH THE AREA NOT SEEING ANY LET ALONE SIGNIFICANT RAINFALL SINCE
THE END OF MAY ANY AREAS THAT DO NOT GET ANY SIGNIFICANT RAIN WITH
COLD FRONT WILL SEE MUCH GREATER MOISTURE DEFICITS AS NO ADDITIONAL
THREAT OF SIGNIFICANT RAINS UNTIL AT LEAST LATE NEXT WEEKEND OR
EARLY NEXT WORK WEEK.
TRS
&&
.FIRE WEATHER...
317 PM CDT
WINDS AND RH VALUES APPROACHING BUT NOT EXPECTED TO REACH RED
FLAG CRITERIA THE REST OF THE AFTERNOON OR EARLY THIS EVENING.
TRS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* NO IMPACTS THROUGH 12Z.
* TSRA POTENTIAL IN THE AFTERNOON HOURS.
BEACHLER
//DISCUSSION...UPDATED 06Z...
LOW LEVEL HIGH PRESSURE HAS PUSHED FURTHER EAST OF THE
REGION...ALLOWING A CONTINUED FEED OF SOUTHERLY WINDS OVER
NORTHERN IL/NORTHWEST IN AIRFIELDS. A COLD FRONTAL BOUNDARY
REMAINS WEST OF THE REGION...HOWEVER WILL CONTINUE TO SLOWLY PUSH
EAST THROUGHOUT THE DAY TODAY. FRONTAL PASSAGE IS EXPECTED TO
OCCUR DURING THE LATE AFTN/EVE HOURS. THEN WINDS VEER
WEST/NORTHWEST DURING THE EVENING AND OVERNIGHT HOURS INTO TUE.
THE OTHER CONCERN IS IN REGARDS TO TSRA DEVELOPMENT. GUIDANCE HAS
STRUGGLED WITH THE PRECISE TIMING/PLACEMENT/INTENSITY...AND MANY
THINGS STILL NEED TO COME TOGETHER. AT THIS TIME THE BEST TIMING
IS FOR SHRA/TSRA DEVELOPMENT TO OCCUR DURING THE AFTN/EVE
HOURS...THEN PUSH EAST INTO NORTHERN IN. AT THIS TIME GIVEN THE
LOW CONFIDENCE HAVE MAINTAINED THE PROB30 GROUP...AND WILL ALLOW
FOR FURTHER ADJUSTMENTS AS WE APPROACH THE LATE MORNING HOURS.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE IN ALL ELEMENTS THROUGH 16Z.
* MEDIUM CONFIDENCE ON TSRA DEVELOPMENT AFT 16Z.
* LOW CONFIDENCE ON COVERAGE OF TSRA.
* HIGH CONFIDENCE IN WIND DIR/SPEED FORECAST.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...
TUESDAY THROUGH SATURDAY...VFR.
RATZER
&&
.MARINE...
202 PM...SOUTHERLY FLOW WILL CONTINUE THROUGH MONDAY AFTERNOON
UNTIL A COLD FRONT MOVES ACROSS LAKE MICHIGAN MONDAY EVENING. A
LARGE AREA OF LOW PRESSURE OVER SOUTHERN CANADA WILL EVENTUALLY
CONSOLIDATE INTO ONE LOW AND SLOWLY LIFT NORTHEAST TO HUDSON BAY
MONDAY. THE GRADIENT IS STILL EXPECTED TO TIGHTEN SOME...
ESPECIALLY OVER THE NORTHERN PORTION OF THE LAKE WHERE 15-25KTS IS
POSSIBLE. WINDS WILL SLOWLY DIMINISH AHEAD OF THE FRONT AND THEN
SHIFT NORTHWEST BEHIND THE FRONT MONDAY EVENING INTO MONDAY NIGHT.
HIGH PRESSURE BUILDS ACROSS THE PLAINS TUESDAY...MAINTAINING A
NORTHWESTERLY FLOW ACROSS THE LAKE AND AS THE HIGH SPREADS EAST IN
THE AFTERNOON...EXPECT THE GRADIENT TO WEAKEN ENOUGH FOR A LAKE
BREEZE TO FORM ACROSS NORTHEAST IL AND NORTHWEST INDIANA. THE HIGH
WILL MOVE ACROSS THE LAKES REGION TUESDAY NIGHT INTO WEDNESDAY WITH
LIGHT WINDS BECOMING SOUTHERLY THURSDAY AS THE HIGH DEPARTS. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1109 PM CDT SUN JUN 10 2012
.DISCUSSION...
ISSUED 852 PM CDT SUN JUN 10 2012
LATEST SURFACE ANALYSIS INDICATES THE COLD FRONT WHICH WILL AFFECT
OUR AREA ON MONDAY WAS LOCATED OVER EXTREME WESTERN IOWA EARLY THIS
EVENING. CONVECTION HAS BEEN ORGANIZING ALONG AND JUST TO THE EAST
OF THE FRONT OVER THE PAST SEVERAL HOURS AND SEEMS TO BE GETTING
BETTER ORGANIZED...ESPECIALLY ACRS SOUTHWEST IOWA INTO SE NEBRASKA
WHERE THE CONVERGENCE WAS MOST PRONOUNCED OVER THE PAST SEVERAL
HOURS. SHORT TERM MODELS CONTINUE TO SUGGEST THE CONVECTION WILL
PUSH EAST AND SOUTHEAST THRU IOWA AND INTO NORTHERN MISSOURI LATE
THIS EVENING AND INTO THE EARLY MORNING HOURS WITH A GRADUAL WEAKENING
TREND AS IT TRACKS TO EXTREME EASTERN IOWA AND NE MISSOURI TOWARDS
300 AM...AND POSSIBLY INTO PARTS OF WEST CENTRAL IL JUST BEFORE DAWN.
THE 00Z ILX AND SGF SOUNDINGS SHOWING A FAIRLY STRONG CAP IN PLACE
EARLY THIS EVENING WITH OUR AREAS IN BETWEEN THE BETTER MOISTURE
SOURCES...WITH THE DEEP TROPICAL MOISTURE ASSOCIATED WITH THE SOUTHERN
MISSISSIPPI VALLEY UPPER WAVE MAINLY ACRS THE EAST AND SE SECTIONS
OF OUR FORECAST AREA...AND THE BETTER LOW LEVEL MOISTURE AHEAD OF
THE FRONT LOCATED IN A NARROW SW-NE CORRIDOR JUST AHEAD OF THE COLD
FRONT. THE BETTER INSTABILITY FROM THE SPC MESOANALYSIS WAS LOCATED
ACROSS PARTS OF SOUTHWEST IOWA INTO EASTERN KS AND NW MO WHERE SURFACE
BASE CAPES WERE IN THE 2500 TO 3000 J/JG OVER THE PAST HOUR WITH
THE ELEVATED MIXED LAYER STARTING TO ERODE THANKS TO THE INCREASING
SFC MOISTURE CONVERGENCE AND JET DYNAMICS. PROPAGATION VECTORS
SUGGEST THE MORE ORGANIZED CONVECTION MAY START TO TURN SE INTO
PARTS OF NW MO AND NE KS EARLY THIS EVENING AS THE NORTHERN PORTION
OF THE CONVECTION WEAKENS SOME AS IT TRACKS FURTHER EAST.
THIS TYPE OF SCENARIO DOES NOT BODE WELL WITH RESPECT TO SEEING SOME
DECENT RAINFALL ACRS OUR AREA ON MONDAY. WHAT IS LEFT OF THE CONVECTION
WILL PUSH ACRS WESTERN IL DURING THE MORNING AND POSSIBLY REDEVELOP
ALONG OR EAST OF THE I-55 CORRIDOR DURING THE AFTERNOON AS THE COLD
FRONT APPROACHES THE AREA. UPPER LEVEL SUPPORT AS WELL AS ANY LOW
LEVEL CONVERGENCE DOES NOT LOOK THAT GREAT FOR ANY SIGNIFICANT
ORGANIZATION TO THE CONVECTION TOMORROW AHEAD OF THE COLD FRONT...DESPITE
THE MODERATE INSTABILITY SEEN ON MODELS...NEVER THE LESS...WE SHOULD
SEE AT LEAST SOME SCATTERED SHOWERS AND THUNDERSTORMS ACRS THE AREA
DURING THE DAY BUT THIS CERTAINLY DOESN`T LOOK LIKE IT WILL PRODUCE
WIDESPREAD RAINFALL...WHICH WE DESPERATELY NEED.
THE CURRENT ZONE FORECAST IS IN GOOD SHAPE THIS EVENING...SO OTHER
THAN THE USUAL EARLY EVENING TWEAKS TO THE HOURLY TEMPERATURE
GRIDS...NO OTHER ADJUSTMENTS WILL BE NEEDED...AS A RESULT NO ZONE
UPDATE WILL BE NEEDED.
&&
.AVIATION...
ISSUED 1105 PM CDT SUN JUN 10 2012
LOOKING AT MAINLY VFR CONDITIONS THRU THIS FORECAST PERIOD. STILL
SOME QUESTIONS WITH RESPECT TO TIMING OF CONVECTION...OR WHAT IS
LEFT OF THE CONVECTION CURRENTLY GOING ACRS CENTRAL IOWA AND ANY
AFFECT ON CIGS ACRS OUR AREA TOMORROW MORNING. TIMING OF PRECIP
STILL LOOKS TO BE IN THE 10Z-14Z TIME FRAME ACRS THE WEST BEFORE
DISSIPATING. MAY SEE SOME RE-DEVELOPMENT ALONG OR JUST EAST OF
I-55 BETWEEN 18Z-22Z WITH COVERAGE STILL LIMITED ENOUGH TO CONTINUE
WITH VCTS. ANY CONVECTION THAT DOES FORM LATE TOMORROW MORNING OR
EARLY AFTN SHOULD PUSH EAST OF THE TAF SITES BY 00Z WITH THE
ACTUAL COLD FRONT LAGGING SEVERAL HOURS BEHIND THE PRECIP. SURFACE
WINDS WILL CONTINUE FROM A SE DIRECTION OVERNIGHT AT 5 TO 10
KTS...AND THEN WINDS WILL BEGIN TO VEER MORE INTO THE SOUTHWEST
TOMORROW WITH SPEEDS RUNNING FROM 10 TO 15 KTS. THE WIND WILL
SHIFT INTO THE WEST LATE TOMORROW AFTN AND EVENING AS THE FRONT
EDGES ACRS THE FORECAST AREA.
SMITH
&&
.PREV DISCUSSION...
ISSUED 257 PM CDT SUN JUN 10 2012
SHORT TERM...TONIGHT THROUGH WEDNESDAY
UPPER-LEVEL DISTURBANCE CURRENTLY OVER THE LOWER MISSISSIPPI
RIVER VALLEY WILL CONTINUE TO SPREAD MOISTURE NORTHWARD INTO THE
REGION TONIGHT. LATEST SATELLITE/RADAR LOOPS INDICATE THE DEEPER
MOISTURE AND ASSOCIATED PRECIP ARE PRIMARILY LIMITED TO LOCATIONS
ALONG AND TO THE RIGHT OF THIS FEATURE. AS A RESULT...THE BEST
RAIN CHANCES WILL SPREAD INTO THE TENNESSEE AND OHIO RIVER
VALLEYS TONIGHT...GENERALLY STAYING EAST OF ILLINOIS. HIGH-RES
MODELS SUCH AS THE HRRR ARE KEEPING THE KILX CWA DRY...HOWEVER
WITH DEEPER MOISTURE COMING SO CLOSE TO THE E/SE...HAVE OPTED TO
MAINTAIN A SLIM CHANCE FOR SHOWERS ALONG/EAST OF I-57 TONIGHT.
MEANWHILE...VIGOROUS UPPER WAVE OVER THE NORTHERN ROCKIES WILL
TRACK ALONG THE CANADIAN BORDER TOWARD THE NORTHERN GREAT LAKES BY
MONDAY EVENING. TRAILING COLD FRONT WILL CROSS THE MISSISSIPPI
RIVER BY AROUND MIDDAY MONDAY AND BE LOCATED ALONG THE I-55
CORRIDOR BY EARLY MONDAY EVENING. AIRMASS AHEAD OF THE FRONT WILL
BECOME MODERATELY UNSTABLE...CHARACTERIZED BY CAPE VALUES OF 1500
TO 2500J/KG. MITIGATING FACTOR FOR WIDESPREAD THUNDERSTORMS AND
SEVERE POTENTIAL WILL BE LACK OF WIND SHEAR. FORECAST SOUNDINGS
INDICATE WEAK WIND PROFILE THROUGHOUT THE ENTIRE DEPTH OF THE
ATMOSPHERE AND VERY WEAK 0-6 KM BULK SHEAR VALUES OF 15 TO 25KT.
DESPITE LACK OF SHEAR...ADEQUATE INSTABILITY AND GOOD CONVERGENCE
ALONG THE ADVANCING FRONT WILL RESULT IN A BROKEN LINE OF
STORMS...WITH A LOW PROBABILITY FOR SEVERE. PRIMARY TIME FRAME
WILL BE DURING THE LATE MORNING/AFTERNOON WEST OF I-55...AND
DURING THE EVENING FURTHER EAST. ANY CONVECTION WILL QUICKLY EXIT
INTO INDIANA AFTER MIDNIGHT...WITH CLEARING SKIES NOTED FROM WEST
TO EAST ACROSS THE AREA TOWARD DAWN.
HIGH PRESSURE WILL BUILD INTO THE GREAT LAKES BEHIND THE DEPARTING
COLD FRONT ON TUESDAY AND WEDNESDAY...BRINGING A COOLER/DRIER
AIRMASS INTO THE REGION. WITH 850MB TEMPS PROGGED TO DROP INTO THE
12 TO 14C RANGE...HIGHS WILL FALL BACK TO NEAR NORMAL FOR THIS
TIME OF YEAR IN THE UPPER 70S/LOWER 80S.
LONG TERM...THURSDAY THROUGH SUNDAY
MODELS CONTINUE TO ADVERTISE UPPER TROUGHING DEVELOPING ACROSS THE
WESTERN CONUS BY THE END OF THE WEEK...RESULTING IN DOWNSTREAM
RIDGING AND WARMER WEATHER FOR THE MIDWEST. EXACT EVOLUTION AND
DEGREE OF AMPLIFICATION STILL REMAIN IN QUESTION...WITH A
SLIGHTLY DIFFERENT SOLUTION FEATURED ON EACH SUCCESSIVE MODEL RUN.
GIVEN UNCERTAINTIES...HAVE OPTED TO MAINTAIN A DRY FORECAST
THROUGH NEXT WEEKEND EVEN THOUGH THE ECMWF SUGGESTS A FRONT MAY
APPROACH FROM THE NORTHWEST BY SUNDAY. 12Z 10 JUN GFS IS MUCH
STRONGER WITH THE EASTERN RIDGE AND DEVELOPS A REX BLOCK ACROSS
THE GREAT LAKES/OHIO RIVER VALLEY. IF THIS SOLUTION PANS OUT...THE
NEXT CHANCE FOR RAIN WOULD BE DELAYED PERHAPS UNTIL THE MIDDLE OF
NEXT WEEK. WILL THEREFORE MAINTAIN WARM/DRY CONDITIONS THROUGH
SUNDAY...UNTIL BETTER MODEL CONSISTENCY IS ACHIEVED.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1230 AM EDT MON JUN 11 2012
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 308 PM EDT SUN JUN 10 2012
AN UPPER SYSTEM WILL MOVE SOUTHEAST OF THE AREA ON MONDAY BRINGING
SOME RAIN TO THE AREA...THEN A COLD FRONT WILL MOVE THROUGH ON
MONDAY NIGHT BRINGING ADDITIONAL CHANCES FOR RAIN. HIGH PRESSURE
WILL THEN BUILD IN AND DRY WEATHER INTO NEXT WEEKEND.
&&
.NEAR TERM /OVERNIGHT/...
ISSUED AT 940 PM EDT SUN JUN 10 2012
MID AND HIGH LEVEL CLOUDS ASSOCIATED WITH THE UPPER LEVEL
DISTURBANCE OVER THE TENNESSEE VALLEY CONTINUING TO SPREAD INTO
THE REGION THIS EVENING. HAVE SEEN A FEW SPRINKLES/VERY LIGHT RAIN
SHOWERS MOVING NORTH THROUGH SOUTHERN FORECAST AREA. TEMPS WERE IN
THE UPPER 70S AND LOWER 80S AT 01Z.
NOT MUCH CHANGE TO CURRENT FORECAST FOR THE OVERNIGHT. ONLY EXCEPTION
WILL BE TO MAKE SOME REFINEMENTS TO POPS BASED ON RADAR AND
SATELLITE TRENDS AND SUPPORTED BY MOST RECENT SHORT RANGE MODEL
GUIDANCE. GREATER COVERAGE TO RAINFALL ASSOCIATED WITH THE UPPER
DISTURBANCE FROM MIDDLE TENNESSEE SOUTH INTO ALABAMA/GEORGIA
CURRENTLY. RAP APPEARS TO CAPTURE THIS ACTIVITY WELL THIS
EVENING...TRACKING IT N/NE OVERNIGHT AND INTO THE OHIO VALLEY
TOWARDS DAYBREAK. WILL CONTINUE WITH LIKELY POPS OVER FAR
SOUTHEAST COUNTIES WHERE CONFIDENCE IS HIGHEST IN MEASURABLE
PRECIP LATE. DROPPED BACK TO LOW CHANCE POPS FURTHER NORTH AND
WEST OVER MUCH OF THE REMAINDER OF THE FORECAST AREA. ALSO REMOVED
ISOLATED THUNDER FROM ALL BUT FAR SOUTHEAST COUNTIES WITH ONLY
WEAK ELEVATED CAPE VALUES PRESENT AND LITTLE IN THE WAY OF
LIGHTNING STRIKES WITH PRECIP SHIELD TO OUR SOUTH.
ZONE AND GRID UPDATES OUT SHORTLY.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
ISSUED AT 308 PM EDT SUN JUN 10 2012
FOCUS IS ON RAIN CHANCES EARLY IN THE PERIOD. NAM IS A LITTLE
STRONGER THAN THE OTHER MODELS AND STANDS OUT...SO WENT CLOSER TO
GFS/ECMWF.
UPPER SYSTEM TO OUR EAST WILL STILL BE CLOSE ENOUGH FOR LOW END
LIKELY POPS MONDAY MORNING ACROSS THE EAST AND CHANCE POPS
ELSEWHERE. THEN FOR THE AFTERNOON THE FORECAST AREA WILL BE IN
BETWEEN THE EASTERN SYSTEM AND A COLD FRONT APPROACHING FROM THE
WEST. THUS WENT CHANCE POPS ALL AREAS DURING THE AFTERNOON.
THE FRONT WILL MOVE IN MONDAY NIGHT...BUT BY THEN TIMING IS NOT
FAVORABLE AS INSTABILITY WILL BE DIMINISHING. THUS AGAIN ONLY WENT
CHANCE POPS DURING THE EVENING...DECREASING OVERNIGHT.
ONLY KEPT SLIGHT CHANCE POPS IN THE FAR EAST ON TUESDAY TO ACCOUNT
FOR ANY LINGERING SHOWERS BEHIND THE FRONT...BUT THIS WILL PROBABLY
BE ABLE TO BE REMOVED IF CURRENT MODEL TRENDS CONTINUE.
DRY CONDITIONS WILL THEN MOVE IN THROUGH WEDNESDAY AS HIGH PRESSURE
MOVES IN.
AS FAR AS TEMPERATURES ARE CONCERNED...WENT CLOSER TO THE WARMER MAV
ON MONDAY AS NOTED ABOVE MOST OF THE AREA WILL BE IN BETWEEN SYSTEMS
DURING THE DAY. STUCK CLOSE TO MODEL BLEND FOR MUCH OF THE REST OF
THE PERIOD.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
ISSUED AT 308 PM EDT SUN JUN 10 2012
HIGH PRESSURE OVER THE GREAT LAKES WILL SLOWLY MAKES ITS WAY TOWARDS
NEW ENGLAND KEEPING CONDITIONS DRY THROUGHOUT THE PERIOD. THE GFS
AND CANADIAN DEPICT A WEAK WAVE AND ASSOCIATED VORT MAX POSSIBLY
IMPACTING THE AREA ON SUNDAY. HOWEVER...MODELS CURRENTLY INDICATE
PRECIPITATION CHANCES NOT EXPECTED TO IMPACT THE AREA UNTIL SUNDAY
NIGHT AT THE EARLIEST. THEREFORE...REMOVED ALLBLEND SLIGHT CHANCE
POPS AND CONTINUED WITH AN ENTIRELY DRY FORECAST FOR THE LONG TERM.
TEMPERATURES WILL START OUT NEAR NORMAL VALUES AND GRADUALLY
INCREASE THROUGHOUT THE PERIOD ALLOWING ABOVE NORMAL VALUES TO
RETURN.
&&
.AVIATION /DISCUSSION FOR THE 110600Z TAFS/...
ISSUED AT 1230 AM EDT MON JUN 11 2012
EXPECTING CEILINGS TO FALL INTO THE 040-050 RANGE DURING THE PRE
DAWN HOURS AS DEEPER MOISTURE CONTINUES TO ADVECT INTO THE AREA.
UPPER DISTURBANCE CURRENTLY OVER THE TENNESSEE VALLEY EXPECTED TO
DRIFT NORTHEAST INTO THE LOCAL AREA AFTER SUNRISE ON MONDAY. LIFT
LOOKS RATHER DISORGANIZED WITH THIS SYSTEM WITH 850MB WINDS
GENERALLY WEAK. SOME SCATTERED SHOWER ACTIVITY POSSIBLE AFTER
SUNRISE ON MONDAY...ESPECIALLY IN THE VICINITY OF KIND/KBMG...BUT
WITH THE DISORGANIZED LIFT...ONLY MVFR VISIBILITY RESTRICTIONS
EXPECTED IN ANY SHOWERS. HEATING OF THE MOIST BOUNDARY LAYER MAY
RESULT IN SOME AREAS OF MVFR CEILINGS AFTER SUNRISE AS WELL.
A BETTER THREAT FOR ORGANIZED CONVECTION MAY DEVELOP OVER THE TAF
SITES AFTER ABOUT 112000Z WITH THE APPROACH OF A FRONTAL ZONE/UPPER
TROUGH FROM THE WEST.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...RYAN
SHORT TERM...50
LONG TERM....HOMANN/50
AVIATION...JAS/JP
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1214 PM CDT MON JUN 11 2012
...UPDATE TO AVIATION...
.DISCUSSION...
STRONG MOISTURE CONVERGENCE CONTINUES IN FAR NORTHEAST KANSAS
BEHIND SURFACE FRONT...WHICH LIES FROM ROUGHLY FROM KDSM TO KTOP
TO KWLD AT 08Z. GUSTY NORTHEAST WINDS WERE REPORTED AT KMHK AT 08Z
WITH OUTFLOW BOUNDARY SHOWING NEAR THE KTWX RADAR. MUCH DRIER AIR
NOT FAR BEHIND WITH SURFACE DEWPOINTS IN THE UPPER 40S IN NORTH
CENTRAL KANSAS AND LOWER 30S IN NORTHWEST KANSAS. WEAK MID LEVEL
RETURNS SHOWING UP ON WESTERN KANSAS RADARS BUT LITTLE NEARING THE
SURFACE IN MID LEVEL FRONTOGENESIS. 0Z 850MB TEMPS WERE VERY CLOSE
TO 20C THROUGHOUT THE SURROUNDING STATES...THOUGH TEMPS BELOW 10C
WERE SAMPLED IN MONTANA.
WILL GO ALONG WITH HRRR AND RUC WITH CONVECTION SLOWLY PUSHING
SOUTHEAST OUT OF THE AREA THIS MORNING AS THE MODIFIED CONTINENTAL
AIRMASS MOVES IN. WESTERN MID LEVEL RETURNS SHOULD ENCOUNTER THIS
DRIER AIR AND STILL STRUGGLE TO REACH THE GROUND. COLD AIR ADVECTION
TAKES ITS TIME GETTING HERE HOWEVER...WITH SOMEWHAT INCREASED LEVELS
COMING LATE IN THE DAY. WITH SOME EARLY DAY HIGH CLOUD AS
WELL...THIS MAY KEEP NORTHERN AREAS IN THE MID 80S...WITH SOME UPPER
80S ALONG I-70 WHERE EARLY DAY DEBRIS IS MORE REMOVED AND BETTER
CALL WILL HOLD OFF LONGER.
TONIGHT INTO TUESDAY PERIODS LOOK RATHER QUIET WITH SURFACE HIGH
PASSING ACROSS NEBRASKA AND IOWA AND 700-850MB RIDGING OVER EASTERN
KANSAS. MAY SEE SOME HIGH CLOUD MOVE OUT OF THE ROCKIES TUESDAY WITH
HIGHS A LITTLE COOLER THAN TODAY.
MODELS HAVE BEEN FAIRLY CONSISTENT WITH A WEAK UPPER WAVE MOVING
THROUGH LATE TUESDAY NIGHT INTO WEDNESDAY EVENING. SOUTHERLY LOW/MID
LEVEL FLOW WILL SLOWLY INCREASE RESULTING IN WEAK ISENTROPIC LIFT
WHILE PRECIPITABLE WATER VALUES RISE TO AROUND 1.3 INCHES BY LATE
WEDNESDAY. COMBINED FORCING AND DEEPER MOISTURE MAY BE ENOUGH FOR
SOME CONVECTION...THOUGH COVERAGE IS MUCH IN QUESTION AT THIS POINT.
WILL KEEP POPS ON THE LOW SIDE WEDNESDAY AND WEDNESDAY
NIGHT...KEEPING TUESDAY NIGHT DRY AT THIS POINT. WEAK MID LEVEL
LAPSE RATES SHOULD KEEP STRONG INSTABILITY IN CHECK.
WARM AND HUMID CONDITIONS TO RULE MUCH OF THE EXTENDED PERIODS WITH
LITTLE CHANGE IN AIRMASS FROM THE AFOREMENTIONED SITUATION. FAIRLY
GOOD MODEL AGREEMENT WITH WEAK UPPER RIDGE FROM THE SOUTHERN PLAINS
INTO THE GREAT LAKES THROUGH AT LEAST SATURDAY AND STRONG FORCING
MECHANISM APPEAR LACKING...BUT ALSO LACKING IS STRONG CAPPING. SMALL
PRECIPITATION CHANCES...NEAR CLIMATOLOGICAL VALUES FOR MID JUNE...
WILL BE KEPT FOR THE BULK OF THESE PERIODS WITH TEMPS SOMEWHAT ABOVE
NORMAL.
65
&&
.AVIATION...
VFR CONDITIONS ARE FORECAST THROUGH THE TAF PERIOD. NORTH WINDS
WILL PERSIST WITH GUSTS APPROACHING 20 KTS TODAY...BUT WILL TAPER
OFF TO LIGHT NNE OR NEAR CALM AFTER SUNSET THROUGH THE REMAINDER
OF THE TAF.
BARJENBRUCH
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
642 AM CDT MON JUN 11 2012
...UPDATE TO AVIATION...
.DISCUSSION...
STRONG MOISTURE CONVERGENCE CONTINUES IN FAR NORTHEAST KANSAS
BEHIND SURFACE FRONT...WHICH LIES FROM ROUGHLY FROM KDSM TO KTOP
TO KWLD AT 08Z. GUSTY NORTHEAST WINDS WERE REPORTED AT KMHK AT 08Z
WITH OUTFLOW BOUNDARY SHOWING NEAR THE KTWX RADAR. MUCH DRIER AIR
NOT FAR BEHIND WITH SURFACE DEWPOINTS IN THE UPPER 40S IN NORTH
CENTRAL KANSAS AND LOWER 30S IN NORTHWEST KANSAS. WEAK MID LEVEL
RETURNS SHOWING UP ON WESTERN KANSAS RADARS BUT LITTLE NEARING THE
SURFACE IN MID LEVEL FRONTOGENESIS. 0Z 850MB TEMPS WERE VERY CLOSE
TO 20C THROUGHOUT THE SURROUNDING STATES...THOUGH TEMPS BELOW 10C
WERE SAMPLED IN MONTANA.
WILL GO ALONG WITH HRRR AND RUC WITH CONVECTION SLOWLY PUSHING
SOUTHEAST OUT OF THE AREA THIS MORNING AS THE MODIFIED CONTINENTAL
AIRMASS MOVES IN. WESTERN MID LEVEL RETURNS SHOULD ENCOUNTER THIS
DRIER AIR AND STILL STRUGGLE TO REACH THE GROUND. COLD AIR ADVECTION
TAKES ITS TIME GETTING HERE HOWEVER...WITH SOMEWHAT INCREASED LEVELS
COMING LATE IN THE DAY. WITH SOME EARLY DAY HIGH CLOUD AS
WELL...THIS MAY KEEP NORTHERN AREAS IN THE MID 80S...WITH SOME UPPER
80S ALONG I-70 WHERE EARLY DAY DEBRIS IS MORE REMOVED AND BETTER
CALL WILL HOLD OFF LONGER.
TONIGHT INTO TUESDAY PERIODS LOOK RATHER QUIET WITH SURFACE HIGH
PASSING ACROSS NEBRASKA AND IOWA AND 700-850MB RIDGING OVER EASTERN
KANSAS. MAY SEE SOME HIGH CLOUD MOVE OUT OF THE ROCKIES TUESDAY WITH
HIGHS A LITTLE COOLER THAN TODAY.
MODELS HAVE BEEN FAIRLY CONSISTENT WITH A WEAK UPPER WAVE MOVING
THROUGH LATE TUESDAY NIGHT INTO WEDNESDAY EVENING. SOUTHERLY LOW/MID
LEVEL FLOW WILL SLOWLY INCREASE RESULTING IN WEAK ISENTROPIC LIFT
WHILE PRECIPITABLE WATER VALUES RISE TO AROUND 1.3 INCHES BY LATE
WEDNESDAY. COMBINED FORCING AND DEEPER MOISTURE MAY BE ENOUGH FOR
SOME CONVECTION...THOUGH COVERAGE IS MUCH IN QUESTION AT THIS POINT.
WILL KEEP POPS ON THE LOW SIDE WEDNESDAY AND WEDNESDAY
NIGHT...KEEPING TUESDAY NIGHT DRY AT THIS POINT. WEAK MID LEVEL
LAPSE RATES SHOULD KEEP STRONG INSTABILITY IN CHECK.
WARM AND HUMID CONDITIONS TO RULE MUCH OF THE EXTENDED PERIODS WITH
LITTLE CHANGE IN AIRMASS FROM THE AFOREMENTIONED SITUATION. FAIRLY
GOOD MODEL AGREEMENT WITH WEAK UPPER RIDGE FROM THE SOUTHERN PLAINS
INTO THE GREAT LAKES THROUGH AT LEAST SATURDAY AND STRONG FORCING
MECHANISM APPEAR LACKING...BUT ALSO LACKING IS STRONG CAPPING. SMALL
PRECIPITATION CHANCES...NEAR CLIMATOLOGICAL VALUES FOR MID JUNE...
WILL BE KEPT FOR THE BULK OF THESE PERIODS WITH TEMPS SOMEWHAT ABOVE
NORMAL.
65
&&
.AVIATION...
CONVECTION HAS MOVED OFF TO THE SOUTHEAST OF THE TOP AND FOE
TERMINALS. A MID CLOUD DECK QWITH SOME LOWER STRATUS WILL CLEAR
OUT BY 15Z THIS MORNING. VFR CONDITIONS ARE EXPECTED THROUGH THE
PERIOD. NORTH TO NORTHWEST WIND NEAR 10 KTS EXPECTED THROUGH
12/01Z THEN BECOME NORTH NORTHEAST LESS THAN 5 KTS.
53
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
326 AM CDT MON JUN 11 2012
.DISCUSSION...
STRONG MOISTURE CONVERGENCE CONTINUES IN FAR NORTHEAST KANSAS
BEHIND SURFACE FRONT...WHICH LIES FROM ROUGHLY FROM KDSM TO KTOP
TO KWLD AT 08Z. GUSTY NORTHEAST WINDS WERE REPORTED AT KMHK AT 08Z
WITH OUTFLOW BOUNDARY SHOWING NEAR THE KTWX RADAR. MUCH DRIER AIR
NOT FAR BEHIND WITH SURFACE DEWPOINTS IN THE UPPER 40S IN NORTH
CENTRAL KANSAS AND LOWER 30S IN NORTHWEST KANSAS. WEAK MID LEVEL
RETURNS SHOWING UP ON WESTERN KANSAS RADARS BUT LITTLE NEARING THE
SURFACE IN MID LEVEL FRONTOGENESIS. 0Z 850MB TEMPS WERE VERY CLOSE
TO 20C THROUGHOUT THE SURROUNDING STATES...THOUGH TEMPS BELOW 10C
WERE SAMPLED IN MONTANA.
WILL GO ALONG WITH HRRR AND RUC WITH CONVECTION SLOWLY PUSHING
SOUTHEAST OUT OF THE AREA THIS MORNING AS THE MODIFIED CONTINENTAL
AIRMASS MOVES IN. WESTERN MID LEVEL RETURNS SHOULD ENCOUNTER THIS
DRIER AIR AND STILL STRUGGLE TO REACH THE GROUND. COLD AIR ADVECTION
TAKES ITS TIME GETTING HERE HOWEVER...WITH SOMEWHAT INCREASED LEVELS
COMING LATE IN THE DAY. WITH SOME EARLY DAY HIGH CLOUD AS
WELL...THIS MAY KEEP NORTHERN AREAS IN THE MID 80S...WITH SOME UPPER
80S ALONG I-70 WHERE EARLY DAY DEBRIS IS MORE REMOVED AND BETTER
CALL WILL HOLD OFF LONGER.
TONIGHT INTO TUESDAY PERIODS LOOK RATHER QUIET WITH SURFACE HIGH
PASSING ACROSS NEBRASKA AND IOWA AND 700-850MB RIDGING OVER EASTERN
KANSAS. MAY SEE SOME HIGH CLOUD MOVE OUT OF THE ROCKIES TUESDAY WITH
HIGHS A LITTLE COOLER THAN TODAY.
MODELS HAVE BEEN FAIRLY CONSISTENT WITH A WEAK UPPER WAVE MOVING
THROUGH LATE TUESDAY NIGHT INTO WEDNESDAY EVENING. SOUTHERLY LOW/MID
LEVEL FLOW WILL SLOWLY INCREASE RESULTING IN WEAK ISENTROPIC LIFT
WHILE PRECIPITABLE WATER VALUES RISE TO AROUND 1.3 INCHES BY LATE
WEDNESDAY. COMBINED FORCING AND DEEPER MOISTURE MAY BE ENOUGH FOR
SOME CONVECTION...THOUGH COVERAGE IS MUCH IN QUESTION AT THIS POINT.
WILL KEEP POPS ON THE LOW SIDE WEDNESDAY AND WEDNESDAY
NIGHT...KEEPING TUESDAY NIGHT DRY AT THIS POINT. WEAK MID LEVEL
LAPSE RATES SHOULD KEEP STRONG INSTABILITY IN CHECK.
WARM AND HUMID CONDITIONS TO RULE MUCH OF THE EXTENDED PERIODS WITH
LITTLE CHANGE IN AIRMASS FROM THE AFOREMENTIONED SITUATION. FAIRLY
GOOD MODEL AGREEMENT WITH WEAK UPPER RIDGE FROM THE SOUTHERN PLAINS
INTO THE GREAT LAKES THROUGH AT LEAST SATURDAY AND STRONG FORCING
MECHANISM APPEAR LACKING...BUT ALSO LACKING IS STRONG CAPPING. SMALL
PRECIPITATION CHANCES...NEAR CLIMATOLOGICAL VALUES FOR MID JUNE...
WILL BE KEPT FOR THE BULK OF THESE PERIODS WITH TEMPS SOMEWHAT ABOVE
NORMAL.
65
&&
.AVIATION...
PRIMARY UPPER LEVEL FORCING SHOULD EXIT THE AREA BY 06Z TAKING THE
MAJORITY OF THE CONVECTION WITH IT SO HAVE WENT WITH A DRY FCST
AT ALL TAFS SITES. HOWEVER...OUTFLOW BOUNDARY MAY STILL SERVE TO
DEVELOP SOME ISOLATED CONVECTION BEFORE 09Z...BUT CHANCES APPEAR
TOO LOW TO INCLUDE IN THE TERMINAL FCSTS. FRONT AND OUTFLOW
COMBINATION WILL KEEP NORTH/NORTH WINDS THROUGH 12Z AND THEN INCREASE
SLIGHTLY. ONLY SCT-BKN STRATOCU THROUGH 12Z THEN A FEW AC BEYOND 12Z.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS JACKSON KY
140 AM EDT MON JUN 11 2012
.UPDATE...
ISSUED AT 140 AM EDT MON JUN 11 2012
WELL...RADAR CONTINUES TO PAINT LIGHT RETURNS ACROSS OUR SWRN
COUNTIES BUT IT STILL APPEARS THAT VERY LITTLE OF THIS IS REACHING
THE GROUND. MODELS CONTINUE TO RUN AMUCK WITH PRECIP OVERNIGHT BUT
GENERALLY APPEAR TO BE OVER DOING THINGS BASED ON CURRENT OBS/TRENDS.
WILL GO AHEAD AND SCALE POPS BACK A BIT FOR THE NEXT FEW HOURS BUT
WILL ALSO KEEP SOME CHANCES IN FOR AROUND DAYBREAK.
UPDATE ISSUED AT 1036 PM EDT SUN JUN 10 2012
LATEST NAM AND RUC HAVE REALLY BACKED OFF ON PRECIPITATION ACROSS
SOUTHEAST KENTUCKY THROUGH THE REMAINDER OF THE NIGHT. THIS MAY BE
DUE TO THE CONTINUED DOWNSLOPING (DRYING) FLOW. IF THIS IS THE
CASE...MUCH OF THE AREA MAY GET ROBBED OVERNIGHT. HOWEVER...AREAS
ALONG AND NORTH OF THE MOUNTAIN PARKWAY MAY NOT FEEL THIS INFLUENCE
AS MUCH WITH DEWPOINTS POOLING A BIT HIGHER ACROSS THE AREA.
THUS...THE NAM DEPICTION OF A BAND OF PRECIPITATION FORMING ACROSS
OUR NORTH SEEMS REASONABLE AND WILL DRIFT NORTH TOWARDS DAYBREAK INTO
NORTHERN KENTUCKY. MEANWHILE...LOW LEVEL JET WILL LIKELY BLOSSOM AN
AREA OF SHOWERS ACROSS CENTRAL TENNESSEE LATE TONIGHT AND THESE WILL
LIKELY PUSH NORTH ALONG THE I-75 CORRIDOR THROUGH DAYBREAK AND
BEYOND. AGAIN...NOT SURE HOW MUCH INFLUENCE COULD BE ATTRIBUTED TO
THE DOWNSLOPING FLOW...BUT THE EVOLUTION OF THIS SYSTEM WILL NEED TO
BE WATCHED AS IT TOO COULD FALL APART AND BECOME MORE SCATTERED
SHOWERS OR SPRINKLES AT BEST. REGARDLESS...STILL A BIT OF A CHANCE WE
COULD END UP STAYING DRY IN SEVERAL AREAS THROUGH DAYBREAK AND
PERHAPS WELL INTO MONDAY AS WELL.
UPDATE ISSUED AT 806 PM EDT SUN JUN 10 2012
LOOKING AT ALL AVENUES IN WHICH WE COULD ACHIEVE THUNDER TONIGHT CAME
BACK NEGATIVE. LIFTING PARCELS FROM MANY DIFFERENT LEVELS COULD NOT
GENERATE ENOUGH INSTABILITY TO WARRANT THUNDER LATE TONIGHT. THIS IS
SUPPORTED BY THE LACK OF LIGHTNING UPSTREAM. ALTHOUGH WE ARE
ANTICIPATING NEW DEVELOPMENT...IT WILL LIKELY TRANSITION INTO MORE
RAIN SHOWERS. IT WOULD TAKE SOME PRETTY VIGOROUS UPDRAFTS TO GET
MOISTURE ABOVE THE VERY HIGH FREEZING LEVEL...THUS...FEEL SAFE
REMOVING THUNDER. STILL NOT CONFIDENT TO GO ANY HIGHER WITH
POPS...BUT WE MAY NEED TO GO HIGHER WITH A LATER UPDATE IF THINGS
BEGIN TO DEVELOP AS EXPECTED. HOWEVER...AT THIS TIME...PREFER TO WAIT
AND SEE AND STICK WITH OUR 60 TO 70 POPS. IT STILL LOOKS LIKE SHOWERS
SHOULD BEGIN TO DEVELOP NEAR THE TENNESSEE BORDER AROUND 1 OR 2
AM...THEN SPREAD NORTHWARD...REACHING THE I-64 CORRIDOR BY 4 OR 5
AM...AND INTO NORTHERN KENTUCKY AROUND DAYBREAK. AFTER THE INITIAL
SURGE OF MOISTURE AND RAIN...IT APPEARS WE COULD DRY OUT BEHIND THIS
FEATURE TOMORROW MORNING...LEADING TO A DRIER PERIOD DURING THE MID
MORNING HOURS. THEN WE MAY HAVE TO WAIT FOR DAYTIME INSTABILITY TO
REFIRE THINGS IN THE AFTERNOON IF WE DON`T HAVE TOO MANY CLOUDS
AROUND TO PREVENT THE DEVELOPMENT OF INSTABILITY. REGARDLESS...STILL
PLENTY OF QUESTIONS SWIRLING AROUND TOMORROW`S FORECAST. GOING TO
HOLD OFF TO MAKE ANY CHANGES AS MUCH WILL BE DETERMINED IN THE NEXT 6
TO 12 HOURS.
UPDATE ISSUED AT 524 PM EDT SUN JUN 10 2012
DECIDED TO INTRODUCE A FEW HOURS OF SPRINKLES FOR AREAS SOUTH OF THE
HAL ROGERS PARKWAY FOR THIS EVENING. CEILINGS ARE AROUND 5KFT...SO I
IMAGINE A FEW DROPS ARE MAKING IT TO THE SURFACE. STILL LOOKS LIKE
THE BEST FORCING WITH THE MAIN PRECIPITATION WILL HOLD OFF UNTIL
AROUND OR SHORTLY AFTER MIDNIGHT. THE TARGETED AREAS EARLY...WILL BE
NEAR THE TENNESSEE BORDER WITH THE THREAT FOR RAIN PUSHING INTO
NORTHERN KENTUCKY TOWARDS DAYBREAK. DOWNSLOPING MAY KEEP INITIAL
PRECIPITATION TOTALS ON THE LIGHT SIDE AND PERHAPS NOT EVEN
MEASURABLE ACROSS SOUTHEAST KENTUCKY...BUT EVENTUALLY THE FORCING
SHOULD WIN OUT. LOWER CLOUD DECK HAS BROUGHT SOME EARLIER COOLING
INTO OUR SOUTHERN COUNTIES...SO HAVE ADJUSTED THE HOURLY TEMPERATURE
TRACE TO REFLECT THIS EARLIER COOLING. NO NEED TO UPDATE ZONES WITH
ANY OF THESE CHANGES.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 259 PM EDT SUN JUN 10 2012
EASTERN KENTUCKY REMAINS SANDWICHED BETWEEN AN AREA OF SURFACE HIGH
PRESSURE SITUATED OFF OF THE CAROLINA COAST...AND OCCLUDING LOW
PRESSURE ACROSS SOUTH CENTRAL CANADA...LINKED TO A NEARLY STATIONARY
FRONT ALIGNED NORTH TO SOUTH ALONG THE PLAINS. ALOFT...PLENTIFUL
MOISTURE HAS BEEN FEEDING IN FROM THE SOUTHWEST OUT AHEAD OF A SLOW-
MOVING SHORT WAVE TROUGH THAT HAS BEEN PLAGUING THE GULF COAST FOR
THE PAST FEW DAYS. MEANWHILE...A MORE STOUT UPPER LEVEL TROUGH IS
MOVING EAST ALONG THE U.S./CANADIAN BORDER.
DOWNSLOPING SOUTHEASTERLY WINDS HAVE BEEN SCOURING OUT ANY
PRECIPITATION THAT HAS TRIED TO MAKE IT IN FROM THE SOUTH
TODAY...WITH ONLY A FEW SPRINKLES NOTED THUS FAR. THIS TREND LOOKS TO
CONTINUE THROUGH THIS EVENING.
THE MODELS ARE IN GOOD AGREEMENT WITH SLOWLY LIFTING THE GULF WAVE
THROUGH THE TENNESSEE AND OHIO VALLEYS OVER THE NEXT 24 TO 36 HOURS
AS IT GETS GRADUALLY INGESTED INTO THE MAIN WESTERLIES BY THE MORE
DOMINATE NORTHERN STREAM WAVE. THIS WILL BRING ROUNDS OF SHOWERS AND
ISOLATED TO SCATTERED THUNDER TO THE AREA BEGINNING LATER TONIGHT AND
THROUGH THE DAY ON TUESDAY AS DEEP MOISTURE WILL BE IN PLACE...WITH
PERIODS OF WEAK TO MODEST FORCING.
DESPITE VERY HIGH PWATS FOR THIS TIME OF YEAR...AS HAS BEEN
PREVIOUSLY NOTED...INSTABILITY CONTINUES TO BE IN QUESTION WITH SO
MUCH CLOUD COVER...SO AM NOT CONFIDENT THAT THESE VALUES WILL BE
REALIZED. STILL...WITH THIS KIND OF PATTERN IN PLACE...IT CERTAINLY
CONTINUES TO BEAR WATCHING FOR LOCALLY HEAVY RAINERS.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 259 PM EDT SUN JUN 10 2012
LONG RANGE MODELS SHOW A RATHER BAGGY LONGWAVE PATTERN OVER THE
SOUTHERN APPALACHIANS THROUGH THE REST OF THE WORK WEEK. BY THE
WEEKEND...SOME AMPLIFICATION OCCURS AT 500 MB WITH RIDGING TAKING
SHAPE OVER THE UPPER MIDWEST AND GREAT LAKES WHILE STUBBORN
TROUGHINESS HANGS IN ALONG THE EASTERN SEABOARD. THE COLD FRONT AND
UPPER LEVEL LOW WHICH WILL BRING THE EARLY WEEK RAINS WILL BE OFF TO
OUR EAST BY TUESDAY NIGHT AND BROAD...WEAK HIGH PRESSURE WILL BUILD
INTO THE APPALACHIANS FOR THE DURATION OF THE PERIOD.
SENSIBLE WEATHER WILL FEATURE A FEW LINGERING SHOWERS TUESDAY NIGHT
BEHIND OUR DEPARTING FRONTAL SYSTEM. THE REST OF THE PERIOD WILL
LIKELY BE PRECIP FREE FOR MOST FOLKS AS A DRY NORTHEASTERLY FLOW
DOMINATES. A FEW WEAK DISTURBANCES RETROGRADING TO THE SOUTHWEST
UNDER THE BUILDING RIDGE OVER THE GREAT LAKES MAY KICK OFF AN
ISOLATED SHOWER FRIDAY THROUGH SUNDAY. HOWEVER...SURFACE DEWPOINTS
WILL BE FAIRLY LOW AND PWATS ONLY REBOUND TO AROUND AN INCH SO
MODELS MAY BE OVERDOING THE QPF...AT LEAST ON THIS SIDE OF THE
APPALACHIAN SPINE. AS SUCH...HAVE TRIMMED BACK ANY MENTION OF PRECIP
TO JUST THE HIGHER TERRAIN AREAS ALONG THE TN AND VA BORDERS.
TEMPERATURES ARE EXPECTED TO REMAIN PRETTY MUCH NEAR NORMAL THROUGH
THE PERIOD...AND WITH COMFORTABLE DEWPOINTS. OVERNIGHT LOWS WILL
LIKELY SNEAK INTO THE 50S MOST NIGHTS IN THE VALLEYS AS WELL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 140 AM EDT MON JUN 11 2012
VFR CONDITIONS WILL CONTINUE THROUGH THE OVERNIGHT HOURS BUT CIGS ARE
EXPECTED TO BEGIN LOWERING WITH -RA POSSIBLE AT SME AND LOZ. STILL
SOME UNCERTAINTY THOUGH AS TO HOW MUCH PRECIP WILL DEVELOP THROUGH
12Z AND WHAT THE END RESULT WILL BE ON FLIGHT CATS..BUT AM EXPECTING
MVFR CONDITIONS TO MATERIALIZE AROUND DAYBREAK AND CONTINUE THROUGH
THE DAY AS -SHRA BECOME MORE PREVALENT ACROSS ERN KY. STILL CANNOT
RULE OUT SOME THUNDER DURING THE DAY AS WELL...BUT WITH UNCERTAINTY
HERE AS WELL WILL CONTINUE TO ADVERTISE THIS WITH VCTS AT THE
TAF SITES. A COLD FRONT CURRENTLY MOVING THROUGH THE MIDWEST IS
EXPECTED TO BEGIN ENCROACHING ON THE AREA LATER TODAY/TONIGHT AND
WILL KEEP UNSETTLED CONDITIONS WITH A CHANCE FOR MORE TSTMS THROUGH
THE END OF THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KAS/MB
SHORT TERM...GEOGERIAN
LONG TERM....ABE
AVIATION...MB
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1012 PM EDT TUE JUN 12 2012
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE WEST TONIGHT AND SLOWLY CROSS
THE REGION ON WEDNESDAY THEN MOVE EAST WEDNESDAY NIGHT. HIGH PRESSURE
FROM NORTHERN CANADA WILL SLOWLY BUILD TOWARD THE REGION THROUGH
THE REMAINDER OF THE WEEK INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
1000 PM UPDATE: FORECAST ON TRACK, NO CHANGES NEEDED AT THIS TIME.
700 PM UPDATE: USING THE RUC MODEL AND RADAR TREND, HAVE DELAYED
THE ONSET OF SHOWERS ACROSS MOST OF THE REGION FROM LATE TONIGHT
UNTIL WEDNESDAY MORNING. ALSO INCREASED CLOUDS A BIT FASTER
TONIGHT THAN PREVIOUS FORECAST BASED ON RH PROGS.
PREVIOUS DISCUSSION: A COLD FRONT CURRENTLY STRETCHING FROM
WESTERN QUEBEC SOUTHWARD THROUGH THE GREAT LAKES WILL CONTINUE TO
TREK EASTWARD TONIGHT AND WILL PASS ACROSS THE STATE TOMORROW.
THIS FEATURE IS PRODUCING A SWATH OF LIGHT TO MODERATE SHOWERS
ACROSS EASTERN NEW YORK AND WESTERN NEW ENGLAND THIS AFTERNOON,
AND THIS TOO WILL SHIFT EASTWARD. PRECIPITATION SHOULD REACH
WESTERN SECTIONS LATE THIS EVENING, BY AROUND MIDNIGHT, BUT IT
WILL BE EARLY TOMORROW MORNING BEFORE IT MAKES IT INTO EASTERN
MAINE. NOT SEEING MUCH EVIDENCE OF SURFACE BASED OR ELEVATED
INSTABILITY OVERNIGHT, SO THERE SHOULDN`T BE ANY THUNDER. HOWEVER
HAVE INCLUDED THE CHANCE OF THUNDERSTORMS TOMORROW AFTERNOON WITH
THE ACTUAL FRONTAL PASSAGE. HEAVY RAIN IS ALSO A POSSIBILITY AS
PWATS WILL BE RUNNING HIGH, 1 TO 1.5+ INCHES, BUT GIVEN THAT THIS
SYSTEM WILL BE WEAKENING AS IT MOVES THROUGH HAVE OPTED TO NOT
INCLUDE HEAVY RAIN IN THE FORECAST FOR NOW. RAINFALL TOTALS WILL
BE HIGHEST IN CENTRAL AND WESTERN MAINE, WHERE 0.50 TO 0.75 INCHES
ARE EXPECTED THROUGH EARLY TOMORROW EVENING. AMOUNTS DROP OFF AS
YOU MOVE SOUTH AND EAST, WITH A TENTH TO A THIRD OF AN INCH ACROSS
EASTERN AND DOWNEAST MAINE. OVERNIGHT LOWS WILL BE MILD GIVEN THE
INFLUX OF MOISTURE, WITH MOST LOCATIONS DROPPING INTO THE MID AND
UPPER 50S. TOMORROW WILL BE MUCH COOLER THAN THE PREVIOUS COUPLE
OF DAYS; HIGHS ARE EXPECTED TO BE IN THE MID AND UPPER 60S.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
MODELS APPEAR TO REASONABLY CONSISTENT WITH THE DEPARTURE TIME OF
SHWRS E OF THE FA WED NGT WITH MAX THU 00-06Z QPF MSLY LESS THAN
0.10 INCHES FOR LOCATIONS EXPERIENCING RNFL...WITH ALL LOCATIONS
DRYING BY THU MORN. WITH WINDS BECOMING N AT 5 TO 10 MPH BEHIND
A COLD FRONT LATE WED NGT AND ERLY THU MORN...CURRENT THINKING IS
THAT THERE WILL NOT BE MUCH TM FOR PATCHY FOG TO FORM IN THE WAKE
OF RNFL...SO FOR NOW WE DID NOT INCLUDE ANY FOG IN THE GRIDS FOR
THIS PD...BUT BRIEF FOG CANNOT BE COMPLETELY RULED FOR A FEW
LOCATIONS.
OTHERWISE...MODELS HAVE BACKED OFF OF KEEPING CLDNSS AND ASSOCIATED
SHWRS WITH THE UPPER LOW SE OF NOVA SCOTIA ACROSS SRN PTNS OF THE
FA THU INTO THU NGT...SO WE LOWERED POPS BLO SLGT CHC AND ALLOWED
FOR AT LEAST PARTIAL CLRG.
WITH HI PRES BOTH AT THE SFC ALD ALF SLOWLY SUBSIDING SWRD FROM
NRN/CNTRL CAN...FAIR SKIES AND LGT WINDS WILL CONT INTO FRI. LOW
AND HI TEMPS WED NGT THRU THU NGT SHOULD BE NEAR NORMAL FOR THIS
TM OF SEASON...WITH A SLIGHT WARMING TREND BEGINNING ON FRI.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
A STRONG RIDGE OF HIGH PRESSURE IS EXPECTED TO REMAIN ACROSS THE
NORTHEAST THIS WEEKEND THROUGH MUCH OF NEXT WEEK BRING EXCEPTIONALLY
WARM WEATHER TO THE REGION. AFTER A CLEAR NIGHT FRIDAY
NIGHT...SATURDAY IS EXPECTED TO BE SUNNY WITH HIGH PRESSURE BOTH AT
THE SURFACE AND ALOFT CRESTING OVER THE AREA. THE HIGH WILL REMAIN
IN PLACE ON SUNDAY BRINGING ANOTHER MOSTLY SUNNY AND VERY WARM DAY.
CLOUDS MAY INCREASE LATE IN THE DAY AS A WEAK SHORTWAVE SLIDES
ACROSS THE NORTH AND SOME SCATTERED LATE DAY SHOWERS OR
THUNDERSHOWERS ARE POSSIBLE ACROSS THE NORTH. SURFACE HIGH PRESSURE
WILL THEN SLIDE SOUTH OF THE AREA EARLY NEXT WEEK. SOUTHWESTERLY
WINDS JUST NORTH OF THE HIGH WILL THEN CHANNEL VERY WARM AIR INTO
THE NORTHEAST FROM THE MIDWEST. THE WEAK DISTURBANCE OVER THE FAR
NORTH MAY BRING SOME SHOWERS OR THUNDERSHOWERS ACROSS THE NORTH
MONDAY INTO TUESDAY. OTHERWISE...THE DAYS WILL BE PARTLY
CLOUDY...WARM AND HUMID. THE WARMEST AIR MAY THEN REACH THE STATE
DURING MID WEEK WHEN TEMPS ON WEDNESDAY AND AGAIN ON THURSDAY COULD
SOAR WELL INTO THE 80S AND POSSIBLY REACH 90 OR HIGHER IN SOME AREAS
UNDER MOSTLY SUNNY SKIES.
&&
.AVIATION /02Z WEDNESDAY THROUGH SUNDAY/...
NEAR TERM: VFR CEILINGS WILL LOWER TO MVFR CEILING AFTER MIDNIGHT,
AND REMAIN MVFR IN RAIN SHOWERS WEDNESDAY. CEILINGS WILL REMAIN
MVFR THROUGH THE REMAINDER OF THE DAY AND MAY OCCASIONALLY DIP
BELOW 1000 FT IN HEAVIER SHOWERS. SCATTERED THUNDERSTORMS ARE
POSSIBLE WEDNESDAY AFTERNOON.
SHORT TERM: ALL SITES WILL INITIALLY BEGIN MVFR WITH LOW CLGS AND
OCNL VSBYS BETWEEN 3 TO 6 SM IN SHWRS WED EVE AND THEN IMPROVE TO
VFR BY THU MORN BEHIND A COLD FRONT. ALL SITES SHOULD THEN CONT
VFR THRU SUN.
&&
.MARINE...
NEAR TERM: A COLD FRONT WILL APPROACH THE WATERS LATE TONIGHT AND
MOVE ACROSS THE AREA LATE TOMORROW. WHILE WINDS AND WAVES WILL
INCREASE IN RESPONSE, THEY ARE EXPECTED TO REMAIN BELOW SMALL
CRAFT LEVELS. THEREFORE, NO HEADLINES ARE NEEDED.
SHORT TO LONG TERM: BOTH WINDS AND SEAS WILL REMAIN BLO SCA
CRITERIA THRU SUN...WITH WINDS INCREASING TO 10 TO 15 KT FROM
THE N BEHIND A COLD FRONT THU INTO THU NGT...THEN GRADUALLY
DIMINISHING FRI INTO THE WEEKEND. USED A BLEND OF NAM12...GFS40
AND GMOS FOR WINDS AND KEPT CLOSE TO WW3 WV GUIDANCE FOR WV HTS...
LOWERED FOR BAYS IMMEDIATELY ADJACENT TO THE COAST.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...FOSTER/HASTINGS
SHORT TERM...VJN
LONG TERM...BLOOMER
AVIATION...FOSTER/HASTINGS
MARINE...FOSTER/HASTINGS/VJN
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
647 PM EDT MON JUN 11 2012
.SYNOPSIS...
A COLD FRONT WILL BRING SHOWERS AND A CHANCE FOR THUNDERSTORMS
TONIGHT INTO TUESDAY. HIGH PRESSURE IS THEN EXPECTED TO BRING DRY
WEATHER THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TUESDAY/...
RADAR LOOP SHOWS WIDELY SCATTERED SHOWERS DEVELOPING OVER RLX THE
PAST FEW HOURS AND SLOWLY MOVING NORTHWARD. LATEST HRRR AND RAP MODELS
SUGGEST MORE SCATTERED SHOWERS TO DEVELOP TONIGHT BEFORE TAPERING
OFF IN THE MID MORNING HOURS. THUS HAVE INCREASED POPS SLIGHTLY TO
INCLUDE MORE CATEGORICAL AREAS TONIGHT. KEPT ONLY SLIGHT CHANCE OF
THUNDER TONIGHT AS INSTABILITY REMAINS MINIMAL AND CIN BEGINNING TO
FORM OVER THE REGION.
COLD FRONT WILL THEN PASS ACROSS THE REGION TUESDAY AFTERNOON.
SPC HAS CONTINUED TO INCLUDE THE AREA AS A `SEE TEXT` MENTION IN
THE DAY 2 CONVECTIVE OUTLOOK. APPEARS THAT MODERATE INSTABILITY
WILL BE PRESENT...BUT ONLY LOW VALUES OF WIND SHEAR WILL BE
PRESENT. AT THIS POINT...APPEARS AS IF THERE WILL ONLY BE A
MINIMAL CHANCE FOR SEVERE WEATHER.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
A CHANCE OF STORMS REMAINS EAST OF I-79 TUESDAY NIGHT...BUT ONLY
THE RIDGES SHOULD HAVE A CHANCE FOR PRECIPITATION AFTER MIDNIGHT.
BY WEDNESDAY MORNING HIGH PRESSURE WILL BE CENTERED OVER LOWER
MICHIGAN...AND THE HIGH WILL DRIFT INTO QUEBEC THROUGH THE REST OF
THE PERIOD. WITH LAKE ERIE TEMPERATURES STILL IN THE 60S AND
NORTHERLY WINDS WEDNESDAY AND WEDNESDAY NIGHT...TEMPERATURES WILL
BE A FEW DEGREES BELOW NORMAL DURING THAT TIME. AS WINDS SHIFT TO
THE EAST FOR THURSDAY...HIGHS WILL RISE BY A FEW DEGREES.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
BLEND OF RECENT ECMWF AND NAEFS MODEL OUTPUT SHOW UPPER LEVEL RIDGE
BUILDING ACROSS THE EASTERN U.S. THIS PERIOD, AS UPPER LEVEL
TROUGHING IS PROJECTED ACROSS THE WESTERN U.S.
HENCE EXPECT THE UPPER OHIO VALLEY TO BE DRY THROUGH THE WEEKEND
WITH TEMPERATURES EACH DAY SLIGHTLY WARMER THAN THE PREVIOUS. BLEND
OF GFS AND ECMWF MOS SHOW TEMPERATURES FRIDAY TO BE NEAR NORMAL,
THEN GRADUALLY WARMING TO VALUES 5 TO 8 DEGREES WARMER THAN NORMAL
SUNDAY AND MONDAY.
BY EARLY NEXT WEEK, THE SURFACE HIGH CENTER COULD BE OFFSHORE,
BECOMING WHAT IS TERMED A BERMUDA HIGH, WHICH WOULD ALLOW WEAK
LOWLEVEL SOUTHERLY WINDS TO BRING INCREASING HUMIDITY TO THE UPPER
OHIO VALLEY. THIS WOULD PROMOTE A SLIGHT CHANCE OF LATE DAY
INSTABILITY THUNDERSTORMS STARTING MONDAY OR TUESDAY.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
BLEND OF RECENT RADAR AND SURFACE DATA, COUPLED WITH HRRR AND
WRF-NMM MODEL OUTPUT, SHOW A PREFRONTAL SURGE OF MVFR SHOWERS TO
MOVE NORTHWARD THROUGH THE UPPER OHIO VALLEY THROUGH EARLY EVENING.
AS SURFACE TEMPERATURES WARM PAST 78, ISOLATED THUNDERSTORMS CAN
DEVELOP.
MVFR CONDITIONS WILL BE PREVALENT TONIGHT, AND MAY LOWER TO IFR LATE
TONIGHT, DEPENDING ON THE EXTENT THAT EVAPORATING RAINFALL SATURATES
A NOCTURNALLY-COOLING SURFACE LAYER. WITH THE MODELS SHOWING SHOWER
COVERAGE DECREASING BY MIDDAY TUESDAY, CONDITIONS CAN LIFT TO VFR
PRIOR TO THE COLD FRONTAL PASSAGE, ALTHOUGH A FRONTAL BAND OF
SHOWERS AND POSSIBLE THUNDERSTORMS CAN CAUSE A BRIEF TEMPORARY DROP
TO MVFR TUESDAY AFTERNOON.
SURFACE WINDS WILL BE MAINLY FROM THE SOUTH AT ABOUT 10 KTS THROUGH
TUESDAY MORNING, WITH GUSTS TO 20 KTS POSSIBLE THIS AFTERNOON.
SURFACE WINDS WILL BE WESTERLY TUESDAY AFTERNOON WITH THE COLD
FRONTAL PASSAGE.
.OUTLOOK...TUESDAY NIGHT THROUGH SATURDAY...
EXCEPT FOR POSSIBLE RESTRICTIONS EARLY WEDNESDAY MORNING IF FOG
DEVELOPS, POST FRONTAL DRYING AND ENSUING HIGH PRESSURE SUBSIDENCE
WILL PROMOTE VFR INTO THE WEEKEND.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
330 PM EDT MON JUN 11 2012
.SYNOPSIS...
A COLD FRONT WILL BRING SHOWERS AND A CHANCE FOR THUNDERSTORMS
TONIGHT INTO TUESDAY. HIGH PRESSURE IS THEN EXPECTED TO BRING DRY
WEATHER THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TUESDAY/...
RADAR SHOWS THAT SHOWERS HAVE MADE PROGRESS ALL THE WAY TO
INTERSTATE 80...ALTHOUGH EARLIER RETURNS THIS AFTERNOON HAVE BEEN
VIRGA. SHOWERS HAVE BEEN QUITE SCATTERED IN COVERAGE...WITH NO
THUNDERSTORMS IN THE REGION EITHER. HAVE CONTINUED TO BACK OFF POPS
IN THE NEAR TERM...ALTHOUGH COVERAGE IS EXPECTED TO INCREASE OVER
TIME. HAVE CONTINUED LIKELY/CATEGORICAL SHOWERS OVERNIGHT...ALTHOUGH
AM CONCERNED THAT HIGH-RESOLUTION MODELS NEVER SHOW ANYTHING
RESEMBLING STRATIFORM COVERAGE. WILL CONTINUE SLIGHT CHANCE FOR
THUNDER OVERNIGHT AND INTO TUESDAY MORNING...ACCORDING TO SREF
CALIBRATED PROBABILITIES. COLD FRONT WILL THEN PASS ACROSS THE
REGION LATE TUESDAY MORNING INTO TUESDAY AFTERNOON. SPC HAS
CONTINUED TO INCLUDE THE AREA AS A `SEE TEXT` MENTION IN THE DAY 2
CONVECTIVE OUTLOOK. APPEARS THAT MODERATE INSTABILITY WILL BE
PRESENT...BUT ONLY LOW VALUES OF WIND SHEAR WILL BE PRESENT. AT THIS
POINT...APPEARS AS IF THERE WILL ONLY BE A MINIMAL CHANCE FOR SEVERE
WEATHER.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
A CHANCE OF STORMS REMAINS EAST OF I-79 TUESDAY NIGHT...BUT ONLY
THE RIDGES SHOULD HAVE A CHANCE FOR PRECIPITATION AFTER MIDNIGHT.
BY WEDNESDAY MORNING HIGH PRESSURE WILL BE CENTERED OVER LOWER
MICHIGAN...AND THE HIGH WILL DRIFT INTO QUEBEC THROUGH THE REST OF
THE PERIOD. WITH LAKE ERIE TEMPERATURES STILL IN THE 60S AND
NORTHERLY WINDS WEDNESDAY AND WEDNESDAY NIGHT...TEMPERATURES WILL
BE A FEW DEGREES BELOW NORMAL DURING THAT TIME. AS WINDS SHIFT TO
THE EAST FOR THURSDAY...HIGHS WILL RISE BY A FEW DEGREES.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
BLEND OF RECENT ECMWF AND NAEFS MODEL OUTPUT SHOW UPPER LEVEL RIDGE
BUILDING ACROSS THE EASTERN U.S. THIS PERIOD, AS UPPER LEVEL
TROUGHING IS PROJECTED ACROSS THE WESTERN U.S.
HENCE EXPECT THE UPPER OHIO VALLEY TO BE DRY THROUGH THE WEEKEND
WITH TEMPERATURES EACH DAY SLIGHTLY WARMER THAN THE PREVIOUS. BLEND
OF GFS AND ECMWF MOS SHOW TEMPERATURES FRIDAY TO BE NEAR NORMAL,
THEN GRADUALLY WARMING TO VALUES 5 TO 8 DEGREES WARMER THAN NORMAL
SUNDAY AND MONDAY.
BY EARLY NEXT WEEK, THE SURFACE HIGH CENTER COULD BE OFFSHORE,
BECOMING WHAT IS TERMED A BERMUDA HIGH, WHICH WOULD ALLOW WEAK
LOWLEVEL SOUTHERLY WINDS TO BRING INCREASING HUMIDITY TO THE UPPER
OHIO VALLEY. THIS WOULD PROMOTE A SLIGHT CHANCE OF LATE DAY
INSTABILITY THUNDERSTORMS STARTING MONDAY OR TUESDAY.
&&
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
BLEND OF RECENT RADAR AND SURFACE DATA, COUPLED WITH HRRR AND
WRF-NMM MODEL OUTPUT, SHOW A PREFRONTAL SURGE OF MVFR SHOWERS TO
MOVE NORTHWARD THROUGH THE UPPER OHIO VALLEY THROUGH EARLY EVENING.
AS SURFACE TEMPERATURES WARM PAST 78, ISOLATED THUNDERSTORMS CAN
DEVELOP.
MVFR CONDITIONS WILL BE PREVALENT TONIGHT, AND MAY LOWER TO IFR LATE
TONIGHT, DEPENDING ON THE EXTENT THAT EVAPORATING RAINFALL SATURATES
A NOCTURNALLY-COOLING SURFACE LAYER. WITH THE MODELS SHOWING SHOWER
COVERAGE DECREASING BY MIDDAY TUESDAY, CONDITIONS CAN LIFT TO VFR
PRIOR TO THE COLD FRONTAL PASSAGE, ALTHOUGH A FRONTAL BAND OF
SHOWERS AND POSSIBLE THUNDERSTORMS CAN CAUSE A BRIEF TEMPORARY DROP
TO MVFR TUESDAY AFTERNOON.
SURFACE WINDS WILL BE MAINLY FROM THE SOUTH AT ABOUT 10 KTS THROUGH
TUESDAY MORNING, WITH GUSTS TO 20 KTS POSSIBLE THIS AFTERNOON.
SURFACE WINDS WILL BE WESTERLY TUESDAY AFTERNOON WITH THE COLD
FRONTAL PASSAGE.
.OUTLOOK...TUESDAY NIGHT THROUGH SATURDAY...
EXCEPT FOR POSSIBLE RESTRICTIONS EARLY WEDNESDAY MORNING IF FOG
DEVELOPS, POST FRONTAL DRYING AND ENSUING HIGH PRESSURE SUBSIDENCE
WILL PROMOTE VFR INTO THE WEEKEND.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
209 PM EDT MON JUN 11 2012
.SYNOPSIS...
A COLD FRONT WILL BRING SHOWERS AND STORMS THIS AFTERNOON THROUGH
TUESDAY, FOLLOWED BY DRY AND SEASONABLE CONDITIONS WEDNESDAY
INTO FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
WITH 115PM UPDATE...HAVE BACKED OFF PRECIPITATION BY A FEW MORE
HOURS IN MOST LOCATIONS. LOW LEVEL MOISTURE IS TAKING ITS TIME
MOVING INTO THE AREA...AND RADAR HAS BEEN SHOWING A LOT OF VIRGA.
THE VIRGA SHOULD EVENTUALLY MOISTEN LOW LEVELS AND ALLOW RAIN AT
THE SURFACE. ALSO TWEAKED AFTERNOON TEMPERATURES...BUMPING UP
NORTHERN COUNTIES UP A DEGREE OR TWO AND DECREASING TEMPERATURES
ACROSS EASTERN OHIO WHERE RAINFALL HAS ALREADY ARRIVED. PREVIOUS
DISCUSSION FOLLOWS.
BASED ON RECENT SATELLITE DATA AND NAM MODEL OUTPUT, EXPECT
SKIES TO BECOME MOSTLY CLOUDY ACROSS THE WHOLE UPPER OHIO VALLEY
BY MIDDAY, AS DEEP MOISTURE MOVES INTO THE REGION WITH UPPER LEVEL
SHORTWAVE MOVING NORTH FROM THE TENNESSEE VALLEY.
THIS WILL MERGE WITH A COLD FRONT AND A DEEPER TOUGH MOVING EAST
FROM THE UPPER GREAT LAKES TO PRODUCE WIDESPREAD SHOWERS AND
THUNDERSTORMS THIS AFTERNOON THROUGH TONIGHT.
RAINFALL AMOUNTS OVER ONE HALF INCH WITH LOCALLY AN INCH
EXPECTED. SEVERE THREAT WILL BE LIMITED BY A LACK OF LOW LEVEL
INSTABILITY AT THE SURFACE AND BEST UPPER LEVEL DYNAMICS WELL WEST
OF REGION.
WITH MID AND UPPER LEVEL CLOUDS ALREADY ENTERING REGION LOWERED
MAX TEMPS TOWARD MAV MOS. QUITE MILD AND HUMID TONIGHT AHEAD OF
FRONT.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
SHOWERS AND THUNDERSTORMS WILL BE LIKELY TUESDAY UNTIL THE COLD
FRONTAL PASSAGE AND LOW LEVEL DRYING TOWARD EVENING. ISOLATED
SEVERE THREAT WITH AMOUNT OF AVAILABLE INSTABILITY IN DOUBT AS WELL
AS WEAKENING UPPER LEVEL DYNAMICS. TRENDED TOWARD THE NAM AND
ECMWF FOR SHOWERS TO DIMINISH WEST TO EAST TUESDAY EVENING AS DRY
AIR WORKS ACROSS REGION.
MODELS THEN IN GOOD OVERALL AGREEMENT FOR DRY HIGH PRESSURE TO
MOVE EAST WITH MUCH LOWER DEW POINTS AND NEAR NORMAL TEMPERATURES
WEDNESDAY AND THURSDAY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
BLEND OF RECENT ECMWF AND NAEFS MODEL OUTPUT SHOW UPPER LEVEL RIDGE
BUILDING ACROSS THE EASTERN U.S. THIS PERIOD, AS UPPER LEVEL
TROUGHING IS PROJECTED ACROSS THE WESTERN U.S.
HENCE EXPECT THE UPPER OHIO VALLEY TO BE DRY THROUGH THE WEEKEND
WITH TEMPERATURES EACH DAY SLIGHTLY WARMER THAN THE PREVIOUS. BLEND
OF GFS AND ECMWF MOS SHOW TEMPERATURES FRIDAY TO BE NEAR NORMAL,
THEN GRADUALLY WARMING TO VALUES 5 TO 8 DEGREES WARMER THAN NORMAL
SUNDAY AND MONDAY.
BY EARLY NEXT WEEK, THE SURFACE HIGH CENTER COULD BE OFFSHORE,
BECOMING A WHAT IS TERMED A BERMUDA HIGH, WHICH WOULD ALLOW
WEAK LOWLEVEL SOUTHERLY WINDS TO BRING INCREASING HUMIDITY TO THE
UPPER OHIO VALLEY AND SO PROMOTE A SLIGHT CHANCE OF LATE DAY
INSTABILITY THUNDERSTORMS STARTING MONDAY OR TUESDAY.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
BLEND OF RECENT RADAR AND SURFACE DATA, COUPLED WITH HRRR AND
WRF-NMM MODEL OUTPUT, SHOW A PREFRONTAL SURGE OF MVFR SHOWERS TO
MOVE NORTHWARD THROUGH THE UPPER OHIO VALLEY THROUGH EARLY EVENING.
AS SURFACE TEMPERATURES WARM PAST 78, ISOLATED THUNDERSTORMS CAN
DEVELOP.
MVFR CONDITIONS WILL BE PREVALENT TONIGHT, AND MAY LOWER TO IFR LATE
TONIGHT, DEPENDING ON THE EXTENT THAT EVAPORATING RAINFALL SATURATES
A NOCTURNALLY-COOLING SURFACE LAYER. WITH THE MODELS SHOWING SHOWER
COVERAGE DECREASING BY MIDDAY TUESDAY, CONDITIONS CAN LIFT TO VFR
PRIOR TO THE COLD FRONTAL PASSAGE, ALTHOUGH A FRONTAL BAND OF
SHOWERS AND POSSIBLE THUNDERSTORMS CAN CAUSE A BRIEF TEMPORARY DROP
TO MVFR TUESDAY AFTERNOON.
SURFACE WINDS WILL BE MAINLY FROM THE SOUTH AT ABOUT 10 KTS THROUGH
TUESDAY MORNING, WITH GUSTS TO 20 KTS POSSIBLE THIS AFTERNOON.
SURFACE WINDS WILL BE WESTERLY TUESDAY AFTERNOON WITH THE COLD
FRONTAL PASSAGE.
.OUTLOOK...TUESDAY NIGHT THROUGH SATURDAY...
EXCEPT FOR POSSIBLE RESTRICTIONS EARLY WEDNESDAY MORNING IF FOG
DEVELOPS, POST FRONTAL DRYING AND ENSUING HIGH PRESSURE SUBSIDENCE
WILL PROMOTE VFR INTO THE WEEKEND.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
721 PM EDT TUE JUN 12 2012
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 325 PM EDT TUE JUN 12 2012
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW PROGRESSIVE UPR
TROF EXTENDING FM HUDSON BAY INTO THE GRT LKS MOVING E IN ADVANCE OF
UPR RDG OVER WRN CANADA. SHRTWV EMBEDDED WITHIN THIS TROF BROUGHT
LOTS OF CLDS AND SOME -SHRA TO MAINLY THE NRN TIER INTO EARLY
AFTN... BUT TREND THIS AFTN HAS BEEN FOR MORE SUNSHINE AS DNVA/
LARGER SCALE QVECTOR DVGC/MORE ACYC FLOW AND DRIER AIR SHOWN ON THE
12Z INL RAOB IS FOLLOWING IN THE WAKE OF THAT DISTURBANCE IN ADVANCE
OF SFC HI PRES CENTERED OVER SE SDAKOTA. SKIES ARE MOCLR FM THE HI
CENTER STRETCHING TOWARD LK WINNIPEG...WHERE THE 12Z RAOB AT THE PAS
IN MANITOBA SHOWS A PWAT OF 0.28 INCH. SFC DEWPTS THIS AFTN HAVE
MIXED OUT INTO THE LO-MID 30S IN THIS UPSTREAM AIRMASS. MORE CLDS
ARE PRESENT A BIT FARTHER W IN THE NRN PLAINS IN THE RETURN SW FLOW
ARND THE SFC HI AND IN ADVANCE OF SHRTWV TRACKING E ACRS
WYOMING/MONTANA. 12Z BIS RAOB SHOWS MORE MSTR/PWAT OF 0.70 INCH NEAR
THE WAD CLD BAND.
MAIN FCST CONCERNS IN THE SHORT TERM REVOLVE ARND CLRG TRENDS THIS
AFTN AND THEN TEMPS/POTENTIAL FOR FROST TNGT.
TNGT...SFC HI PRES IS FCST TO MOVE E AND TO OVER NRN LWR MI BY 12Z
WED. EXPECT ANY LINGERING CLDS TO DSPT LATE THIS AFTN/EARLY THIS
EVNG WITH THE ARRIVAL OF MORE ACYC FLOW AND WARMER/DRIER AIR AT
H925. STRONGER WSW FLOW ARND SFC HI IS FCST TO DVLP OVER THE NW HALF
OF THE CWA AFT 06Z...WITH PWAT RISING AS THIS FLOW TAPS MORE MSTR
SHOWN ON THE 12Z BIS RAOB. MOST SUSTAINED CONDITIONS FOR RADIATIONAL
COOLING LOOK TO BE OVER THE SCNTRL AND E...WHERE THE GRADIENT FLOW
WL REMAIN WEAKER/PWAT LOWER AND UNDER 0.5 INCH THRU 12Z WED. OPTED
TO EXTEND GOING FROST ADVY NEAR THE WI BORDER TO INCLUDE MOST OF THE
CWA FROM BARAGA TO THE E...WITH MIN TEMPS CLOSER TO THE LOWER END OF
GUIDANCE IN THESE AREAS PER OBSVD MIXING OF DEWPTS UPSTREAM.
WED...AS SFC HI PRES DRIFTS SLOWLY E ACRS LK HURON...STRONGER SW
FLOW WL DVLP OVER THE ENTIRE CWA. WITH APRCH OF DISTURBANCE NOW
MOVING THRU THE NRN PLAINS AND SOME MSTR RETURN...EXPECT AT LEAST
SOME CLDS TO INVADE MAINLY THE WRN ZNS IN THE AFTN. ALTHOUGH THE GFS
GENERATES SOME PCPN OVER THE FAR W LATE IN THE DAY...PREFER TO
FOLLOW THE DRY 12Z NAM/CNDN/LOCAL WRF-ARW DUE TO VERY DRY NATURE OF
LLVL AIRMASS. MIXING TO H8 ON NAM FCST SDNGS YIELDS HI TEMPS
REBOUNDING TO 70 TO 75 AWAY FM LK MODERATION.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 325 PM EDT TUE JUN 12 2012
THE WEAK HIGH PRESSURE RIDGE IN PLACE FOR WEDNESDAY WILL SLIDE
EASTWARD AS A TROUGH OVER THE CANADIAN PRAIRIE DIGS DOWN INTO THE
NORTHERN PLAINS. MODELS AGREE THAT A SHORTWAVE WILL BE APPROACHING
WESTERN UPPER MICHIGAN BY 00Z THURSDAY...THOUGH THERE SEEMS TO BE
DIFFERENCES WITH HOW STRONG IT WILL BE. THE GEM/ECMWF SEEM TO AGREE
ON A WEAKER SOLUTION...WHILE THE GFS DEVELOPS A SMALL TROUGH. THE
GFS ALSO AMPLIFIES THE EXITING RIDGE MUCH MORE THAN THE OTHER
MODELS. WILL STICK WITH A BLEND MORE SIMILAR TO THE GEM/ECMWF FOR
NOW GIVEN THEIR AGREEMENT...THOUGH CONFIDENCE IS NOT VERY HIGH. THIS
KEEPS MOST OF THE PRECIPITATION THAT WILL OCCUR WITH THIS SHORTWAVE
OVER WESTERN LAKE SUPERIOR AND THE WEST HALF OF THE CWA. WILL KEEP
LOW CHANCE POPS OVER THESE AREAS TO ACCOUNT FOR UNCERTAINTY DURING
THE DAY ON THURSDAY. MODEL SOUNDINGS SUGGEST MIXING TO AROUND
850MB...WHICH PUTS HIGHS IN THE 70S AND PERHAPS LOW 80S. DESPITE
INCOMING CLOUD COVER WITH THE SHORTWAVE...EXPECT THE WARMEST
TEMPERATURES TO BE OUT WEST WITH THE HIGHEST 850MB TEMPS OF AROUND
13C. WITH SKIES MOSTLY SUNNY OUT EAST...EXPECT MIXING TO BRING
RELATIVE HUMIDITY DOWN INTO THE 30 PERCENT RANGE. WITH THE STRONGER
PRESSURE GRADIENT ASSOCIATED WITH THE LOW PRESSURE SYSTEM...EXPECT
GUSTY SOUTHERLY TO SOUTHEASTERLY WINDS ACROSS MUCH OF THE
AREA...MAINLY NORTH CENTRAL AND OVER LAKE SUPERIOR. HIGHEST GUSTS
ARE EXPECTED TO BE AROUND 25 KNOTS.
FRIDAY THE TROUGH WILL SWING JUST NORTH OF LAKE SUPERIOR...REACHING
HUDSON BAY BY 00Z SATURDAY. MODELS SEEM TO BE IN FAIRLY GOOD
AGREEMENT ON THE AMOUNT OF QPF ASSOCIATED WITH THE PASSING FRONT
ACROSS WEST AND CENTRAL UPPER MICHIGAN...WITH AROUND 0.25-0.50 INCH
IMPACTING THE AREA. THE NAM BRINGS THE FRONT ALL THE WAY THROUGH THE
CWA...BRINGING 0.25 INCH TO THE EASTERN AREAS. THE ECMWF/GEM/GFS
TAKE THE BEST UPPER LEVEL FORCING NORTHWARD /PER 850-500MB QVECTOR
CONVERGENCE/ AND THEREFORE KEEP MUCH OF THE EASTERN CWA DRY. THERE
ARE ALSO DIFFERENCES IN TIMING OF PRECIPITATION...SO HAVE LOWERED
CONFIDENCE IN PUTTING SPECIFICS INTO THE FORECAST. KEPT THE BEST
CHANCES OVER LAKE SUPERIOR AND ACROSS THE WEST AND CENTRAL. MU/ML
CAPE VALUES THURSDAY NIGHT INTO FRIDAY AFTERNOON RANGE FROM AROUND
200-1000 J/KG...SO KEPT THUNDER CHANCES IN. WITH PRESSURE GRADIENT
REMAINING TIGHT...WINDS WILL CONTINUE TO GUST INTO THE 20-25 KNOT
RANGE THROUGH FRIDAY EVENING.
FOR THE EXTENDED /THE WEEKEND INTO TUESDAY/...
FOR THE MOST PART...IT SEEMS THROUGH THE WEEKEND A RIDGE WILL CENTER
ITSELF OVER LOWER MICHIGAN...AND SHORTWAVES WILL RIDE AROUND THE
IT BRINGING CHANCES OF PRECIPITATION. FOR THE FIRST PART OF THE
WORK WEEK...A STRONGER LOW PRESSURE TROUGH WILL SWING INTO THE
NORTHERN PLAINS AND BRING ADDITIONAL PRECIPITATION/THUNDERSTORMS TO
MUCH OF THE CWA. HOWEVER...MODELS DIFFER ON TIMING AND PLACEMENT OF
FEATURES. THE GFS/GEM BRING A STRONGER RIDGE UP FROM THE
PLAINS...KEEPING MUCH OF THE PRECIPITATION ASSOCIATED WITH A SECOND
TROUGH/SHORTWAVE CONFINED TO THE WESTERN CWA OR NOT IN THE UPPER
PENINSULA AT ALL. THE GFS EVENTUALLY DEVELOPS THE TROUGH INTO A
CLOSED LOW...AND THEN MOVES THE PRECIPITATION THROUGH ON MONDAY. THE
ECMWF KEEPS THE RIDGE FURTHER SOUTH AND EAST...AND BRINGS A MUCH
MORE POTENT SHORTWAVE INTO UPPER MICHIGAN SATURDAY MORNING INTO
MONDAY. WITH SUCH A VARIANCE IN SOLUTIONS...DO NOT FEEL CONFIDENT
BUMPING UP ANY POPS. WILL KEEP THE MENTION OF THUNDER AS MODELS SEEM
TO BRING IN A DECENT AMOUNT OF INSTABILITY THROUGH THE WEEKEND. AS
FOR HIGH TEMPERATURES...850MB TEMPS LOOK TO BE IN THE 16-18C
RANGE...SO WILL KEEP FORECASTED HIGHS IN THE UPPER 70S TO THE MID
80S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 720 PM EDT TUE JUN 12 2012
HIGH PRESSURE TO DOMINATE THE REGION THROUGH THE FORECAST...
RESULTING IN VFR CONDITIONS. WINDS TO BE LIGHT OVERNIGHT AS THE
PRESSURE GRADIENT RELAXES AND THE BOUNDARY LAYER DECOUPLES. AS THE
HIGH SHIFTS OVER NORTHERN LOWER MICHIGAN ON WEDNESDAY...SOUTHWEST
WINDS TO PICK UP OVER THE AREA WITH SOME GUSTS TO 20 KTS AT KIWD.
INCREASING MID CLOUDS AND WINDS BACKING TO THE SOUTH TO SOUTHEAST
LATE IN THE FORECAST IN RESPONSE TO APPROACHING LOW PRESSURE SYSTEM.
THIS FEATURE COULD BRING AN ISOLATED SHOWER OR THUNDERSTORM TO IWD
BY 0Z THURSDAY...BUT WITH BETTER FORCING AND MOISTURE WELL TO THE
WEST WILL LEAVE OUT AT THIS TIME.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 325 PM EDT TUE JUN 12 2012
EXPECT NW WINDS UP TO 25-30 KTS INTO THIS EVENING OVER THE E TO
DIMINISH OVERNIGHT WITH THE ARRIVAL OF A HI PRES RIDGE. THESE LIGHT
WINDS WILL PERSIST INTO WED NIGHT AS THE HI REMAINS DOMINANT. THEN A
STRONGER S WIND UP TO 25 KTS WILL IMPACT MAINLY THE NCENTRAL AND E
PART OF THE LAKE ON THU/FRI UNDER A TIGHTER PRES GRADIENT BETWEEN
THE HI DEPARTING TO THE E AND A LO PRES TROF APPROACHING FROM THE W.
THEN LIGHTER WINDS WILL PREVAIL AGAIN THIS COMING WEEKEND WITH A
WEAKER PRES GRADIENT FORECAST TO DOMINATE THE UPPER LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FROST ADVISORY FROM 1 AM EDT /MIDNIGHT CDT/ TO 7 AM EDT /6 AM
CDT/ WEDNESDAY FOR MIZ002-004>007-009>014-084-085.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...MCB
AVIATION...RJT
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
419 PM EDT MON JUN 11 2012
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 419 PM EDT MON JUN 11 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A FAIRLY DEEP TROF AND
ASSOC STRONG SHORTWAVE MOVING FM ND INTO NW MN. THE EASTWARD
MOVEMENT OF THIS SHORTWAVE IS HELPING TO SLOWLY PUSH A SFC COLD
FRONT ACROSS WRN UPPER MI THIS AFTERNOON. LATEST 19Z SFC
PLOT/ANALYSIS SHOWS THE FRONT IS ALONG A CRYSTAL FALLS-MICHIGAMME
LINE. ALTHOUGH 12Z MODEL SNDGS INDICATE IN EXCESS OF 1000 J/KG
MLCAPE WITH T/TD OF 82/63...VIS SATELLITE LOOP SHOWS LITTLE DVLPMT
TO CU FIELD UPSTREAM OVER CENTRAL UPPER MI OR IMMEDIATELY UPSTREAM
OVER NRN WI. SUSPECT THAT DRY ALOFT MOVING IN AHEAD OF THE SHORTWAVE
AS NOTED ON VERY DRY 12Z KMPX SNDGS MAY BE INHIBITING CU DVLPMT OVER
THE FCST AREA.
TONIGHT...GIVEN LACK OF CU DVLPMT ON VIS SATELLITE MAY END UP
EVENTUALLY HAVING TO BACK OFF ON POPS TO SLIGHT CHC OVER CENTRAL AND
ERN COUNTIES FOR THIS EVENING AHEAD OF APPROACHING FRONT. IF SOME
CONVECTION IS ABLE TO FIRE ALONG THE FRONT...THERE IS A CHANCE FOR
AN ISOLATED STRONG TO SVR STORM GIVEN THE INSTABILITY AND DEEP LAYER
SHEAR GREATER THAN 40 KTS OVER THE AREA. RELUCTANT TO PULL POPS OUT
COMPLETELY SINCE FRONT IS STILL APPROACHING BUT CHC OF PCPN IS
LOOKING MORE AND MORE DOUBTFUL THIS EVENING OVER CENTRAL AND ERN
CWA. MODEL SNDGS INDICATE WEST WINDS ARE EXPECTED TO PICK UP BEHIND
THE FRONT THIS EVENING ESPECIALLY OVER THE KEWEENAW PENINSULA WHERE
PASSAGE OF SECONDARY COLD FRONT AND INCREASING MIXING/INSTABILITY
WITH COLDER AIR COMING IN MAY PRODUCE GUSTS TO 40 MPH. LOOK FOR LOWS
TO REACH INTO THE MID 40S WEST TO MID 50S SOUTH CENTRAL AND EAST.
TUESDAY...THE 500MB TROUGH AXIS WILL MOVE ACROSS THE AREA MIDDAY
ALONG WITH THE 8H THERMAL TROF AS 850 MB TEMPS LOWER TO AROUND 0C.
WITH GOOD CAA IN THE WNW FLOW OVER THE AREA. WITH LIMITED MIXING
ALONG THE LAKE SUPERIOR SHORE EXPECT HIGHS IN THE LOWER TO MID 50S
WHILE DEEPER SOUTH CENTRAL WILL YIELD HIGHS IN THE LOWER TO MID 60S.
INCREASINGLY ANTICYCLONIC SFC-850 MB FLOW AND RDGG BUILDING IN FROM
THE WEST SHOULD SCOUR OUT LOW CLOUDS FROM WEST TO EAST IN THE
AFTERNOON.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 419 PM EDT MON JUN 11 2012
THE SFC HIGH SHOULD BE DIRECTLY OVERHEAD FROM 00-06Z
WEDNESDAY...BEFORE SHIFTING OFF TO QUEBEC WEDNESDAY AFTERNOON INTO
THURSDAY. SIMILAR TO A FEW DAYS AGO...WE WILL MONITOR THE
DEVELOPMENT OF AN ELONGATED SFC LOW STRETCHING FROM S CENTRAL CANADA
THROUGH THE CO ROCKIES.
FROST WILL REMAIN POSSIBLE TUESDAY NIGHT/WEDNESDAY MORNING...WITH
TEMPS BOTTOMING OUT 31-36F INLAND FROM THE GREAT LAKES AS WINDS GO
NEARLY CALM AND CLOUDS DISSIPATE.
WEDNESDAY WILL LIKELY BE A BIT DRIER THAN ORIGINALLY THROUGH...WITH
MIXED DEW POINTS IN THE MID 20S BY 18Z. THIS SCENARIO WOULD RESULT
IN MIN RH VALUES NEAR 20 PERCENT OVER THE WEST HALF OF UPPER
MI...AND 25-30 PERCENT EAST. EXPECT THE RETURN OF LIGHT/SOUTHERLY
FLOW AS THE HIGH SHIFTS ACROSS LAKE HURON AND STRETCHES THROUGH
QUEBEC...STILL BELOW 15MPH. DID PUSH THE FCST CLOSER TO THESE LOWEST
VALUES.
THE ELONGATED SFC LOW STRETCHING FROM SOUTHERN SASKATCHEWAN/MANITOBA
THROUGH THE DAKOTAS AND E CO/NM THURSDAY MORNING WILL CONTINUE TO
REMAIN NEARLY STEADY. ALTHOUGH THURSDAY SHOULD BE WARMER...WITH
INCREASED SOUTHERLY WINDS /20-35KTS BETWEEN THE SFC AND
850MB/...MOISTURE SHOULD BE ON THE INCREASE AS WELL. MIN RH VALUES
COULD STILL NEAR 30 PERCENT OVER PORTIONS OF INTERIOR W UPPER MI BY
LATE MORNING/EARLY AFTERNOON.
THE FCST FOR SUNDAY MONDAY REMAINS VERY UNCERTAIN...SO DID NOT GO
TOO FAR IN DEPTH WITH ADJUSTMENTS FOR THAT PERIOD. THE WESTERN SFC
LOW WILL BE LOCATED SOMEWHERE BETWEEN NWS ONTARIO AND MN BY 12Z
MONDAY...WITH THE TRAILING COLD FRONT STILL REMAINING TO OUR W BY
THE END OF THE DAY. THE RESULT SHOULD BE ANOTHER ROUND OF WARM/HOT
WEATHER SATURDAY THROUGH MONDAY...AS S WINDS REMAIN STEADY AND 850MB
TEMPS RISE AGAIN TO 16 TO 20C.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 155 PM EDT MON JUN 11 2012
VFR CONDITIONS SHOULD PREVAIL INTO THE EVENING HRS AT
KIWD/KCMX/KSAW. SCT -SHRA/-TSRA COULD FORM BTWN 18-00Z IN VCNTY OF
KSAW ALONG INCOMING COLD FRONT BUT GIVEN CONSIDERABLE UNCERTAINTY IN
PLACEMENT/COVERAGE OF AFTN CONVECTION DUE TO CLOUD COVER...SHRA/TSRA
WERE NOT MENTIONED AT KSAW. WEST WINDS COULD BECOME GUSTY AND PICK
UP SUBSTANTIALLY AT KIWD AND ESPECIALLY KCMX AS A SECONDARY COLD
FRONT PASSES THRU THE AREA LATE AFTN/EVENING. LOOKING
UPSTREAM...MVFR CIGS COULD DEVELOP OVERNIGHT AT KIWD AND KCMX AND
THEN LATE TUE MORNING AT KSAW WITH PASSAGE OF SECONDARY COLD
FRONT.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 419 PM EDT MON JUN 11 2012
LOW PRESSURE ACROSS HUDSON BAY WILL KEEP A TROUGH ACROSS LS THIS
EVENING...AHEAD OF HIGH NEARING FROM THE WEST. EXPECT THE HIGH OVER
MINNESOTA TUESDAY MORNING TO PUSH ACROSS THE UPPER GREAT LAKES
TUESDAY AFTERNOON THROUGH WEDNESDAY...BEFORE EXITING ACROSS QUEBEC
WEDNESDAY NIGHT. W-NW GUSTS OF 30 TO POSSIBLY 30KTS WILL SLIDE IN
OVERNIGHT AND LINGER THROUGH THE DAY TUESDAY. A RIDGE WILL REMAIN
ACROSS LS THROUGH SATURDAY...AS AN ELONGATED AREA OF LOW PRESSURE
ORGANIZES ACROSS THE CENTRAL AND NORTHERN PLAINS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...KF
AVIATION...VOSS
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
157 PM EDT MON JUN 11 2012
.SHORT TERM...(TODAY)
ISSUED AT 518 AM EDT MON JUN 11 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A FAIRLY DEEP TROF MOVING
ACROSS THE NRN PLAINS. AS EXPECTED DUE TO WEAKENING INSTABILITY...
SHRA/TSRA THAT DEVELOPED YESTERDAY AFTN AHEAD OF COLD FRONT IN MN
DIMINISHED AS THEY APPROACHED UPPER MI EARLIER IN THE NIGHT.
HOWEVER...A LINGERING RIBBON OF MUCAPE WHICH HAS RECENTLY INCREASED
TO 500-1000J/KG PER LATEST SPC MESOANALYSIS IS SUPPORTING SCT
SHRA/TSRA WHICH ARE SPREADING/DEVELOPING NE INTO THE WRN FCST AREA
AS OF 09Z.
MAIN CONCERN IN THE SHORT TERM REVOLVES AROUND REDEVELOPMENT OF
CONVECTION TODAY AS COLD FRONT DRIFTS ACROSS THE AREA.
SHRA/TSRA SPREADING INTO WRN UPPER MI WILL PROBABLY PERSIST FOR THE
NEXT FEW HRS GIVEN AVBL INSTABILITY. COLD FRONT SHOULD THEN CLEAR
THE W BEFORE REDEVELOPMENT CAN OCCUR TODAY. TO THE E...DEBRIS CLOUDS
FROM SHRA/TSRA WILL PROBABLY THIN OUT SUFFICIENTLY TO ALLOW FOR
DECENT HEATING AHEAD OF THE COLD FRONT AS IT MOVES ACROSS CNTRL
UPPER MI THIS AFTN. UTILIZING MODIFIED NAM FCST SOUNDINGS FOR T/TD
OF MID 80S/LWR 60S PRIOR TO MODEL GENERATED PCPN (GFS SOUNDING
CONTAMINATED BY PCPN) YIELDS SBCAPE IN THE 1000-1500J/KG RANGE. WITH
DEEP LAYER SHEAR OF 30-40KT...THERE WILL BE THE POTENTIAL FOR
ORGANIZED STORMS AND SVR WX. HIGH RES MODELS GIVE CONFLICTING
SIGNALS ABOUT WHETHER CONVECTION WILL REDVELOP AS SEVERAL INDICATE
LITTLE OR NO REGENERATION TODAY. HOWEVER...GIVEN POTENTIAL
INSTABILITY...SEEMS PRUDENT TO MENTION AT LEAST SCT SHRA/TSRA THIS
AFTN. A QUICK CHECK OF THE 06Z LOCAL HIGH RES WRF AND 4KM NAM ARE
VERY SUPPORTIVE OF THIS IDEA AS THEY SHOW CONVECTION DEVELOPING
ACROSS CNTRL UPPER MI EARLY THIS AFTN AND THEN SPREADING E. APPEARS
THE AREA FROM ROUGHLY CRYSTAL FALLS TO ISHPEMING EASTWARD WILL HAVE
THE POTENTIAL FOR SVR STORMS THIS AFTN. SVR POTENTIAL SHOULD BE
LOWER TOWARD LAKE MICHIGAN ACROSS SE DELTA/SRN SCHOOLCRAFT COUNTIES
WITH SRLY FLOW/MARINE INFLUENCE OFF THE LAKE.
OTHER ITEM OF NOTE TODAY IS THE DRIER AIR MOVING INTO WRN UPPER MI
BEHIND FRONT. SEVERAL PIECES OF GUIDANCE SUGGEST DWPTS FALLING INTO
THE UPPER 40S WHICH RESULTS IN RH FALLING TO AROUND 30PCT THIS AFTN.
WITH WINDS GUSTING TO 20-25MPH THIS AFTN...THERE WILL BE AN
INCREASED RISK OF WILDFIRES WHERE SIGNIFICANT RAINFALL HAS NOT
OCCURRED RECENTLY.
.LONG TERM...(TONIGHT THROUGH SUNDAY)
ISSUED AT 518 AM EDT MON JUN 11 2012
FOR THE START OF THE PERIOD 00Z TUE...A MID LEVEL SHORTWAVE TROUGH
AXIS WILL BE FROM WRN HUDSON BAY TO CENTRAL MN...WITH A SFC LOW OVER
CENTRAL NRN ONTARIO. A COLD FRONT/SFC TROUGH WILL STRETCH S TO
CENTRAL UPPER MI BY 00Z TUE. SOME SHOWERS AND THUNDERSTORMS WILL BE
ONGOING ALONG AND AHEAD OF THE COLD FRONT...BUT THE DRY SLOT WILL BE
MOVING IN AROUND THIS TIME DURING LOSS OF DAYTIME HEATING. THERE IS
A POSSIBILITY OF SOME ELEVATED CONVECTION LATE IN THE EVENING OR
EARLY OVERNIGHT...BUT I THINK THE DRY AIR WILL KEEP THAT FROM
HAPPENING. WILL DEPICT PRECIP WITH CHANCE POPS MOVING OUT OF THE CWA
BY 06Z TUE.
BY 12Z TUE...THE 500MB TROUGH AXIS WILL BE FROM ERN
HUDSON BAY TO WRN LAKE SUPERIOR...WITH THE SFC LOW NEAR JAMES BAY
AND SFC HIGH PRESSURE MOVING INTO WRN MN. THE COLD FRONT WILL BE E OF
THE CWA...WITH GOOD CAA IN THE WNW LOW LEVEL FLOW OVER THE AREA.
850MB TEMPS WILL BE AROUND 3C E AND -1C W. BY 18Z TUE...THE 500MB
TROUGH AXIS WILL BE OVER THE CENTER OF THE CWA...WITH THE SFC HIGH
BEGINNING TO MOVE INTO THE WRN CWA. 850MB TEMPS AT 18Z WILL RANGE
FROM -2C N TO 2C S. BY 00Z WED...THE 500MB TROUGH AXIS WILL BE OVER
FAR ERN UPPER MI...WHILE THE SFC HIGH WILL BE OVER MOST OF THE CWA.
MODEL SOUNDING SUGGEST MIXING TO AROUND 825MB TUE...RESULTING IN
HIGHS IN THE 50S N TO 60S S...AND LOW DEW PTS.
THE SFC HIGH WILL BE CENTERED OVER THE CWA TUE NIGHT...WHICH WILL
LEAD TO FROST POTENTIAL AS COOL TEMPS TUE DROP QUICKLY UNDER MOSTLY
CLEAR SKIES. WENT WITH THE LOW SIDE OF TEMP GUIDANCE...WITH MANY
LOCATIONS OVER THE INTERIOR DROPPING NEAR OR BELOW FREEZING. WILL
KEEP MENTION OF FROST IN HWO.
WED THROUGH FRI...THE SFC HIGH MOVES E WHILE SFC LOW PRESSURE
DEVELOPS WELL TO OUR W IN RESPONSE TO A SERIES OF SHORTWAVES. THE
RESULTING SLY FLOW IN THE LOW LEVELS BRINGS OFF AND ON CONVECTION
FROM LATE WED THROUGH FRI...BUT MODELS INDICATE MOST OF THAT STAYING
W OF THE CWA AND INTO WRN LAKE SUPERIOR. WILL KEEP FORECAST FOR
UPPER MI DRY THROUGH THIS PERIOD AS A DRIER PATTERN HAS VERIFIED
BETTER RECENTLY...AND MOST MODELS KEEP US DRY ANYWAYS. AN UPPER
RIDGE WILL BUILD INTO THE AREA FROM THE S...BRINGING STEADILY
INCREASING TEMPS WED THROUGH AT LEAST FRI. BY FRI...850MB TEMPS
SHOULD BE UP TO 16C...THEN UP TO 18C ON SAT AND SUN. MODELS DIVERGE
ON SOLUTIONS FOR THE WEEKEND...WITH THE 12Z/10 ECMWF BRINGING A
TROUGH PUSHING IN FROM THE NW...WHILE THE 00Z/11 GFS KEEPS THE UPPER
RIDGE IN PLACE. USED A CONSENSUS OF MODELS FOR THE WEEKEND GIVEN LOW
CONFIDENCE IN ANY PARTICULAR MODEL SOLUTION.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 155 PM EDT MON JUN 11 2012
VFR CONDITIONS SHOULD PREVAIL INTO THE EVENING HRS AT
KIWD/KCMX/KSAW. SCT -SHRA/-TSRA COULD FORM BTWN 18-00Z IN VCNTY OF
KSAW ALONG INCOMING COLD FRONT BUT GIVEN CONSIDERABLE UNCERTAINTY IN
PLACEMENT/COVERAGE OF AFTN CONVECTION DUE TO CLOUD COVER...SHRA/TSRA
WERE NOT MENTIONED AT KSAW. WEST WINDS COULD BECOME GUSTY AND PICK
UP SUBSTANTIALLY AT KIWD AND ESPECIALLY KCMX AS A SECONDARY COLD
FRONT PASSES THRU THE AREA LATE AFTN/EVENING. LOOKING
UPSTREAM...MVFR CIGS COULD DEVELOP OVERNIGHT AT KIWD AND KCMX AND
THEN LATE TUE MORNING AT KSAW WITH PASSAGE OF SECONDARY COLD
FRONT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 518 AM EDT MON JUN 11 2012
AHEAD OF A COLD FRONT...S WINDS WILL BE IN THE 15-25KT RANGE OVER
ERN LAKE SUPERIOR TODAY...ESPECIALLY EARLY IN THE DAY. SOME OF THE
HIGHER OBSERVING PLATFORMS WILL SEE WINDS TO AROUND 30KT. BEHIND THE
COLD FRONT...A PUSH OF STRONGER WESTERLY WINDS TO 25-30KT WILL
ARRIVE OVER WRN LAKE SUPERIOR MID/LATE AFTN. THESE STRONGER WINDS
WILL THEN SPREAD ACROSS THE LAKE TONIGHT. LOOK FOR THE WINDS TO
GRADUALLY DIMINISH FROM W TO E TUE WITH WINDS FALLING BLO 15KT TUE
NIGHT AS HIGH PRES ARRIVES OVER THE UPPER LAKES. WINDS WED THRU FRI
SHOULD BE UNDER 20KT AS PRES GRADIENT REMAINS RELATIVELY WEAK BTWN
THE DEPARTING HIGH AND A LOW PRES TROF SETTING UP WELL TO THE W AND
NW.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...VOSS
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
739 AM EDT MON JUN 11 2012
.SHORT TERM...(TODAY)
ISSUED AT 518 AM EDT MON JUN 11 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A FAIRLY DEEP TROF MOVING
ACROSS THE NRN PLAINS. AS EXPECTED DUE TO WEAKENING INSTABILITY...
SHRA/TSRA THAT DEVELOPED YESTERDAY AFTN AHEAD OF COLD FRONT IN MN
DIMINISHED AS THEY APPROACHED UPPER MI EARLIER IN THE NIGHT.
HOWEVER...A LINGERING RIBBON OF MUCAPE WHICH HAS RECENTLY INCREASED
TO 500-1000J/KG PER LATEST SPC MESOANALYSIS IS SUPPORTING SCT
SHRA/TSRA WHICH ARE SPREADING/DEVELOPING NE INTO THE WRN FCST AREA
AS OF 09Z.
MAIN CONCERN IN THE SHORT TERM REVOLVES AROUND REDEVELOPMENT OF
CONVECTION TODAY AS COLD FRONT DRIFTS ACROSS THE AREA.
SHRA/TSRA SPREADING INTO WRN UPPER MI WILL PROBABLY PERSIST FOR THE
NEXT FEW HRS GIVEN AVBL INSTABILITY. COLD FRONT SHOULD THEN CLEAR
THE W BEFORE REDEVELOPMENT CAN OCCUR TODAY. TO THE E...DEBRIS CLOUDS
FROM SHRA/TSRA WILL PROBABLY THIN OUT SUFFICIENTLY TO ALLOW FOR
DECENT HEATING AHEAD OF THE COLD FRONT AS IT MOVES ACROSS CNTRL
UPPER MI THIS AFTN. UTILIZING MODIFIED NAM FCST SOUNDINGS FOR T/TD
OF MID 80S/LWR 60S PRIOR TO MODEL GENERATED PCPN (GFS SOUNDING
CONTAMINATED BY PCPN) YIELDS SBCAPE IN THE 1000-1500J/KG RANGE. WITH
DEEP LAYER SHEAR OF 30-40KT...THERE WILL BE THE POTENTIAL FOR
ORGANIZED STORMS AND SVR WX. HIGH RES MODELS GIVE CONFLICTING
SIGNALS ABOUT WHETHER CONVECTION WILL REDVELOP AS SEVERAL INDICATE
LITTLE OR NO REGENERATION TODAY. HOWEVER...GIVEN POTENTIAL
INSTABILITY...SEEMS PRUDENT TO MENTION AT LEAST SCT SHRA/TSRA THIS
AFTN. A QUICK CHECK OF THE 06Z LOCAL HIGH RES WRF AND 4KM NAM ARE
VERY SUPPORTIVE OF THIS IDEA AS THEY SHOW CONVECTION DEVELOPING
ACROSS CNTRL UPPER MI EARLY THIS AFTN AND THEN SPREADING E. APPEARS
THE AREA FROM ROUGHLY CRYSTAL FALLS TO ISHPEMING EASTWARD WILL HAVE
THE POTENTIAL FOR SVR STORMS THIS AFTN. SVR POTENTIAL SHOULD BE
LOWER TOWARD LAKE MICHIGAN ACROSS SE DELTA/SRN SCHOOLCRAFT COUNTIES
WITH SRLY FLOW/MARINE INFLUENCE OFF THE LAKE.
OTHER ITEM OF NOTE TODAY IS THE DRIER AIR MOVING INTO WRN UPPER MI
BEHIND FRONT. SEVERAL PIECES OF GUIDANCE SUGGEST DWPTS FALLING INTO
THE UPPER 40S WHICH RESULTS IN RH FALLING TO AROUND 30PCT THIS AFTN.
WITH WINDS GUSTING TO 20-25MPH THIS AFTN...THERE WILL BE AN
INCREASED RISK OF WILDFIRES WHERE SIGNIFICANT RAINFALL HAS NOT
OCCURRED RECENTLY.
.LONG TERM...(TONIGHT THROUGH SUNDAY)
ISSUED AT 518 AM EDT MON JUN 11 2012
FOR THE START OF THE PERIOD 00Z TUE...A MID LEVEL SHORTWAVE TROUGH
AXIS WILL BE FROM WRN HUDSON BAY TO CENTRAL MN...WITH A SFC LOW OVER
CENTRAL NRN ONTARIO. A COLD FRONT/SFC TROUGH WILL STRETCH S TO
CENTRAL UPPER MI BY 00Z TUE. SOME SHOWERS AND THUNDERSTORMS WILL BE
ONGOING ALONG AND AHEAD OF THE COLD FRONT...BUT THE DRY SLOT WILL BE
MOVING IN AROUND THIS TIME DURING LOSS OF DAYTIME HEATING. THERE IS
A POSSIBILITY OF SOME ELEVATED CONVECTION LATE IN THE EVENING OR
EARLY OVERNIGHT...BUT I THINK THE DRY AIR WILL KEEP THAT FROM
HAPPENING. WILL DEPICT PRECIP WITH CHANCE POPS MOVING OUT OF THE CWA
BY 06Z TUE.
BY 12Z TUE...THE 500MB TROUGH AXIS WILL BE FROM ERN
HUDSON BAY TO WRN LAKE SUPERIOR...WITH THE SFC LOW NEAR JAMES BAY
AND SFC HIGH PRESSURE MOVING INTO WRN MN. THE COLD FRONT WILL BE E OF
THE CWA...WITH GOOD CAA IN THE WNW LOW LEVEL FLOW OVER THE AREA.
850MB TEMPS WILL BE AROUND 3C E AND -1C W. BY 18Z TUE...THE 500MB
TROUGH AXIS WILL BE OVER THE CENTER OF THE CWA...WITH THE SFC HIGH
BEGINNING TO MOVE INTO THE WRN CWA. 850MB TEMPS AT 18Z WILL RANGE
FROM -2C N TO 2C S. BY 00Z WED...THE 500MB TROUGH AXIS WILL BE OVER
FAR ERN UPPER MI...WHILE THE SFC HIGH WILL BE OVER MOST OF THE CWA.
MODEL SOUNDING SUGGEST MIXING TO AROUND 825MB TUE...RESULTING IN
HIGHS IN THE 50S N TO 60S S...AND LOW DEW PTS.
THE SFC HIGH WILL BE CENTERED OVER THE CWA TUE NIGHT...WHICH WILL
LEAD TO FROST POTENTIAL AS COOL TEMPS TUE DROP QUICKLY UNDER MOSTLY
CLEAR SKIES. WENT WITH THE LOW SIDE OF TEMP GUIDANCE...WITH MANY
LOCATIONS OVER THE INTERIOR DROPPING NEAR OR BELOW FREEZING. WILL
KEEP MENTION OF FROST IN HWO.
WED THROUGH FRI...THE SFC HIGH MOVES E WHILE SFC LOW PRESSURE
DEVELOPS WELL TO OUR W IN RESPONSE TO A SERIES OF SHORTWAVES. THE
RESULTING SLY FLOW IN THE LOW LEVELS BRINGS OFF AND ON CONVECTION
FROM LATE WED THROUGH FRI...BUT MODELS INDICATE MOST OF THAT STAYING
W OF THE CWA AND INTO WRN LAKE SUPERIOR. WILL KEEP FORECAST FOR
UPPER MI DRY THROUGH THIS PERIOD AS A DRIER PATTERN HAS VERIFIED
BETTER RECENTLY...AND MOST MODELS KEEP US DRY ANYWAYS. AN UPPER
RIDGE WILL BUILD INTO THE AREA FROM THE S...BRINGING STEADILY
INCREASING TEMPS WED THROUGH AT LEAST FRI. BY FRI...850MB TEMPS
SHOULD BE UP TO 16C...THEN UP TO 18C ON SAT AND SUN. MODELS DIVERGE
ON SOLUTIONS FOR THE WEEKEND...WITH THE 12Z/10 ECMWF BRINGING A
TROUGH PUSHING IN FROM THE NW...WHILE THE 00Z/11 GFS KEEPS THE UPPER
RIDGE IN PLACE. USED A CONSENSUS OF MODELS FOR THE WEEKEND GIVEN LOW
CONFIDENCE IN ANY PARTICULAR MODEL SOLUTION.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 739 AM EDT MON JUN 11 2012
VFR CONDITIONS SHOULD PREVAIL THRU THIS FCST PERIOD AT
KIWD/KCMX/KSAW. NARROW BAND OF SCT -SHRA/-TSRA PER CURRENT KMQT
RADAR IMAGERY WILL LIKELY AFFECT KSAW UNTIL AROUND 14Z.
OTHERWISE...AS COLD FRONT SLOWLY MOVES ACROSS THE AREA TODAY...
POTENTIAL IS THERE FOR SHRA/TSRA TO REDEVELOP OVER CNTRL UPPER MI
THIS AFTN. WITH CONSIDERABLE UNCERTAINTY IN PLACEMENT/COVERAGE OF
ANY AFTN CONVECTION...SHRA/TSRA WERE NOT MENTIONED AT KSAW. WEST
WINDS COULD BECOME GUSTY AND PICK UP SUBSTANTIALLY AT KIWD AND
ESPECIALLY KCMX AS A SECONDARY COLD FRONT PASSES THRU THE AREA LATE
AFTN/EVENING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 518 AM EDT MON JUN 11 2012
AHEAD OF A COLD FRONT...S WINDS WILL BE IN THE 15-25KT RANGE OVER
ERN LAKE SUPERIOR TODAY...ESPECIALLY EARLY IN THE DAY. SOME OF THE
HIGHER OBSERVING PLATFORMS WILL SEE WINDS TO AROUND 30KT. BEHIND THE
COLD FRONT...A PUSH OF STRONGER WESTERLY WINDS TO 25-30KT WILL
ARRIVE OVER WRN LAKE SUPERIOR MID/LATE AFTN. THESE STRONGER WINDS
WILL THEN SPREAD ACROSS THE LAKE TONIGHT. LOOK FOR THE WINDS TO
GRADUALLY DIMINISH FROM W TO E TUE WITH WINDS FALLING BLO 15KT TUE
NIGHT AS HIGH PRES ARRIVES OVER THE UPPER LAKES. WINDS WED THRU FRI
SHOULD BE UNDER 20KT AS PRES GRADIENT REMAINS RELATIVELY WEAK BTWN
THE DEPARTING HIGH AND A LOW PRES TROF SETTING UP WELL TO THE W AND
NW.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
532 AM EDT MON JUN 11 2012
.SHORT TERM...(TODAY)
ISSUED AT 518 AM EDT MON JUN 11 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A FAIRLY DEEP TROF MOVING
ACROSS THE NRN PLAINS. AS EXPECTED DUE TO WEAKENING INSTABILITY...
SHRA/TSRA THAT DEVELOPED YESTERDAY AFTN AHEAD OF COLD FRONT IN MN
DIMINISHED AS THEY APPROACHED UPPER MI EARLIER IN THE NIGHT.
HOWEVER...A LINGERING RIBBON OF MUCAPE WHICH HAS RECENTLY INCREASED
TO 500-1000J/KG PER LATEST SPC MESOANALYSIS IS SUPPORTING SCT
SHRA/TSRA WHICH ARE SPREADING/DEVELOPING NE INTO THE WRN FCST AREA
AS OF 09Z.
MAIN CONCERN IN THE SHORT TERM REVOLVES AROUND REDEVELOPMENT OF
CONVECTION TODAY AS COLD FRONT DRIFTS ACROSS THE AREA.
SHRA/TSRA SPREADING INTO WRN UPPER MI WILL PROBABLY PERSIST FOR THE
NEXT FEW HRS GIVEN AVBL INSTABILITY. COLD FRONT SHOULD THEN CLEAR
THE W BEFORE REDEVELOPMENT CAN OCCUR TODAY. TO THE E...DEBRIS CLOUDS
FROM SHRA/TSRA WILL PROBABLY THIN OUT SUFFICIENTLY TO ALLOW FOR
DECENT HEATING AHEAD OF THE COLD FRONT AS IT MOVES ACROSS CNTRL
UPPER MI THIS AFTN. UTILIZING MODIFIED NAM FCST SOUNDINGS FOR T/TD
OF MID 80S/LWR 60S PRIOR TO MODEL GENERATED PCPN (GFS SOUNDING
CONTAMINATED BY PCPN) YIELDS SBCAPE IN THE 1000-1500J/KG RANGE. WITH
DEEP LAYER SHEAR OF 30-40KT...THERE WILL BE THE POTENTIAL FOR
ORGANIZED STORMS AND SVR WX. HIGH RES MODELS GIVE CONFLICTING
SIGNALS ABOUT WHETHER CONVECTION WILL REDVELOP AS SEVERAL INDICATE
LITTLE OR NO REGENERATION TODAY. HOWEVER...GIVEN POTENTIAL
INSTABILITY...SEEMS PRUDENT TO MENTION AT LEAST SCT SHRA/TSRA THIS
AFTN. A QUICK CHECK OF THE 06Z LOCAL HIGH RES WRF AND 4KM NAM ARE
VERY SUPPORTIVE OF THIS IDEA AS THEY SHOW CONVECTION DEVELOPING
ACROSS CNTRL UPPER MI EARLY THIS AFTN AND THEN SPREADING E. APPEARS
THE AREA FROM ROUGHLY CRYSTAL FALLS TO ISHPEMING EASTWARD WILL HAVE
THE POTENTIAL FOR SVR STORMS THIS AFTN. SVR POTENTIAL SHOULD BE
LOWER TOWARD LAKE MICHIGAN ACROSS SE DELTA/SRN SCHOOLCRAFT COUNTIES
WITH SRLY FLOW/MARINE INFLUENCE OFF THE LAKE.
OTHER ITEM OF NOTE TODAY IS THE DRIER AIR MOVING INTO WRN UPPER MI
BEHIND FRONT. SEVERAL PIECES OF GUIDANCE SUGGEST DWPTS FALLING INTO
THE UPPER 40S WHICH RESULTS IN RH FALLING TO AROUND 30PCT THIS AFTN.
WITH WINDS GUSTING TO 20-25MPH THIS AFTN...THERE WILL BE AN
INCREASED RISK OF WILDFIRES WHERE SIGNIFICANT RAINFALL HAS NOT
OCCURRED RECENTLY.
.LONG TERM...(TONIGHT THROUGH SUNDAY)
ISSUED AT 518 AM EDT MON JUN 11 2012
FOR THE START OF THE PERIOD 00Z TUE...A MID LEVEL SHORTWAVE TROUGH
AXIS WILL BE FROM WRN HUDSON BAY TO CENTRAL MN...WITH A SFC LOW OVER
CENTRAL NRN ONTARIO. A COLD FRONT/SFC TROUGH WILL STRETCH S TO
CENTRAL UPPER MI BY 00Z TUE. SOME SHOWERS AND THUNDERSTORMS WILL BE
ONGOING ALONG AND AHEAD OF THE COLD FRONT...BUT THE DRY SLOT WILL BE
MOVING IN AROUND THIS TIME DURING LOSS OF DAYTIME HEATING. THERE IS
A POSSIBILITY OF SOME ELEVATED CONVECTION LATE IN THE EVENING OR
EARLY OVERNIGHT...BUT I THINK THE DRY AIR WILL KEEP THAT FROM
HAPPENING. WILL DEPICT PRECIP WITH CHANCE POPS MOVING OUT OF THE CWA
BY 06Z TUE.
BY 12Z TUE...THE 500MB TROUGH AXIS WILL BE FROM ERN
HUDSON BAY TO WRN LAKE SUPERIOR...WITH THE SFC LOW NEAR JAMES BAY
AND SFC HIGH PRESSURE MOVING INTO WRN MN. THE COLD FRONT WILL BE E OF
THE CWA...WITH GOOD CAA IN THE WNW LOW LEVEL FLOW OVER THE AREA.
850MB TEMPS WILL BE AROUND 3C E AND -1C W. BY 18Z TUE...THE 500MB
TROUGH AXIS WILL BE OVER THE CENTER OF THE CWA...WITH THE SFC HIGH
BEGINNING TO MOVE INTO THE WRN CWA. 850MB TEMPS AT 18Z WILL RANGE
FROM -2C N TO 2C S. BY 00Z WED...THE 500MB TROUGH AXIS WILL BE OVER
FAR ERN UPPER MI...WHILE THE SFC HIGH WILL BE OVER MOST OF THE CWA.
MODEL SOUNDING SUGGEST MIXING TO AROUND 825MB TUE...RESULTING IN
HIGHS IN THE 50S N TO 60S S...AND LOW DEW PTS.
THE SFC HIGH WILL BE CENTERED OVER THE CWA TUE NIGHT...WHICH WILL
LEAD TO FROST POTENTIAL AS COOL TEMPS TUE DROP QUICKLY UNDER MOSTLY
CLEAR SKIES. WENT WITH THE LOW SIDE OF TEMP GUIDANCE...WITH MANY
LOCATIONS OVER THE INTERIOR DROPPING NEAR OR BELOW FREEZING. WILL
KEEP MENTION OF FROST IN HWO.
WED THROUGH FRI...THE SFC HIGH MOVES E WHILE SFC LOW PRESSURE
DEVELOPS WELL TO OUR W IN RESPONSE TO A SERIES OF SHORTWAVES. THE
RESULTING SLY FLOW IN THE LOW LEVELS BRINGS OFF AND ON CONVECTION
FROM LATE WED THROUGH FRI...BUT MODELS INDICATE MOST OF THAT STAYING
W OF THE CWA AND INTO WRN LAKE SUPERIOR. WILL KEEP FORECAST FOR
UPPER MI DRY THROUGH THIS PERIOD AS A DRIER PATTERN HAS VERIFIED
BETTER RECENTLY...AND MOST MODELS KEEP US DRY ANYWAYS. AN UPPER
RIDGE WILL BUILD INTO THE AREA FROM THE S...BRINGING STEADILY
INCREASING TEMPS WED THROUGH AT LEAST FRI. BY FRI...850MB TEMPS
SHOULD BE UP TO 16C...THEN UP TO 18C ON SAT AND SUN. MODELS DIVERGE
ON SOLUTIONS FOR THE WEEKEND...WITH THE 12Z/10 ECMWF BRINGING A
TROUGH PUSHING IN FROM THE NW...WHILE THE 00Z/11 GFS KEEPS THE UPPER
RIDGE IN PLACE. USED A CONSENSUS OF MODELS FOR THE WEEKEND GIVEN LOW
CONFIDENCE IN ANY PARTICULAR MODEL SOLUTION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 136 AM EDT MON JUN 11 2012
EXPECT MAINLY VFR CONDITIONS THROUGH THE FCST PERIOD. HOWEVER...THERE
MAY BE PERIOD OF MVFR CIGS AT KIWD EARLY THIS MORNING ASSOCIATED WITH
LOW LEVEL MOISTURE BEHIND A COLD FRONT MOVING INTO WRN UPPER MI. IN
ADDITION...EXPECT LLWS OVERNIGHT WITH A LOW LEVEL JET AHEAD OF THE
COLD FRONT. SCT -SHRA ARE POSSIBLE AS THE FRONT MOVES THROUGH BUT
CONFIDENCE IS ONLY MARGINAL THAT ANY TSRA WILL OCCUR SO WERE NOT INCLUDED
AT THIS TIME. BY MID TO LATE MORNING...CLOUDS CLEAR OUT AS DRY AIR
MOVES IN. WEST WINDS COULD BECOMING GUSTY AND PICK UP SUBSTANTIALLY
AT KCMX AND KIWD BY EVENING AS A SECONDARY COLD FRONT MOVES THROUGH.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 518 AM EDT MON JUN 11 2012
AHEAD OF A COLD FRONT...S WINDS WILL BE IN THE 15-25KT RANGE OVER
ERN LAKE SUPERIOR TODAY...ESPECIALLY EARLY IN THE DAY. SOME OF THE
HIGHER OBSERVING PLATFORMS WILL SEE WINDS TO AROUND 30KT. BEHIND THE
COLD FRONT...A PUSH OF STRONGER WESTERLY WINDS TO 25-30KT WILL
ARRIVE OVER WRN LAKE SUPERIOR MID/LATE AFTN. THESE STRONGER WINDS
WILL THEN SPREAD ACROSS THE LAKE TONIGHT. LOOK FOR THE WINDS TO
GRADUALLY DIMINISH FROM W TO E TUE WITH WINDS FALLING BLO 15KT TUE
NIGHT AS HIGH PRES ARRIVES OVER THE UPPER LAKES. WINDS WED THRU FRI
SHOULD BE UNDER 20KT AS PRES GRADIENT REMAINS RELATIVELY WEAK BTWN
THE DEPARTING HIGH AND A LOW PRES TROF SETTING UP WELL TO THE W AND
NW.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...JLB
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
659 AM CDT MON JUN 11 2012
.UPDATE...
12Z AVIATION DISCUSSION ADDED BELOW.
&&
.DISCUSSION...
SHORTWAVE TROUGH CENTERED OVER LAKE WINNIPEG CANADA WILL CONTINUE
TO LIFT NORTHEAST OVER THE UPPER GREAT LAKES TODAY. COLD POOL
ALOFT ASSOCIATED WITH THE UPPER LEVEL LOW PRESSURE SYSTEM ALONG
WITH ANY DAYTIME HEATING COULD GENERATE ISOLATED SHOWERS OVER
THE FAR NORTHERN SECTION OF OUR FORECAST AREA LATE MORNING THROUGH
MID AFTERNOON. ELSEWHERE...DRIER AIR WILL CONTINUE TO FILTER IN
THROUGH TUESDAY. HIGHS TODAY WILL BE MUCH COOLER THAN PREVIOUS
COUPLE OF DAYS WITH READINGS MAINLY IN THE 70S.
HIGH PRESSURE WILL BEGIN TO BUILD OVER THE NORTHERN PLAINS THIS
AFTERNOON AND OVER THE WESTERN GREAT LAKES AREA LATER TONIGHT AND
TUESDAY. OVERNIGHT LOWS TONIGHT WILL COOL DOWN INTO THE 40S TO LOWER
50S. HIGHS ON TUESDAY WILL WARM BACK INTO THE UPPER 60S AND LOWER
70S.
MEDIUM RANGE MODELS HAVE BEEN CONSISTENT WITH NEXT SHORTWAVE TROUGH
FORECAST TO MOVE INTO THE UPPER MIDWEST WEDNESDAY NIGHT AND THURSDAY
AS THE UPPER AIRFLOW BECOMES MORE ZONAL ACROSS THE NORTHERN TIER OF
CONUS. WL KEEP SOME POPS GOING THROUGH THE REST OF THE WORK WEEK.
UPPER HIGH PRESSURE RIDGE OVER THE EASTERN CONUS WILL RETROGRESS
BACK WEST OVER THE MIDWEST BY THE END OF THE WORK WEEK AND
WEEKEND. THE LATEST LONG TERM MODELS INDICATE A SPLIT UPPER AIR
FLOW OVER THE UPPER MIDWEST. ECMWF MODEL KEEPS MUCH OF THE
PRECIPITATION OVER NORTHERN HALF OF THE STATE. UPPER RIDGE WILL
BRING MUCH OF THE EASTERN FORECAST AREA DRY CONDITIONS ALONG WITH
MAX TEMPERATURES MODERATING INTO THE UPPER 80S.
&&
.AVIATION.../12Z TAF ISSUANCE/
A FEW LINGERING IFR/MVFR CONDITIONS OVER WRN WI WILL QUICKLY GET
PUSHED OUT BY DRIER AIR FROM THE WEST...WITH VFR CONDITIONS
DOMINATING THIS TAF PERIOD. A SECONDARY BOUNDARY IS WORKING INTO
WRN MN RIGHT NOW AND WILL WORK ACROSS MN THIS MORNING AND THROUGH
EAU BY THE EARLY AFTERNOON. WINDS WILL BE SW OUT AHEAD OF THIS
BOUNDARY...AND SWITCH TO THE W BEHIND WHILE ALSO PICKING UP IN
STRENGTH. STRONGEST WINDS WILL BE OVER NW MN...BUT A FEW GUSTS AOA
30 KTS WILL BE POSSIBLE AT MAINLY AXN THIS AFTERNOON. FOR
SHOWERS...THE RAP SHOWS SOME INSTABILITY DEVELOPING AHEAD OF THE
BOUNDARY BY THE AFTERNOON...WITH THE HRRR GENERATING A LINE OF
SHRA AS A RESULT. THE HRRR HAS BEEN DEVELOPING THESE SHOWERS
FURTHER EAST WITH EACH SUCCESSIVE RUN...AND WHAT WAS NEAR MSP WITH
THE 04Z RUN IS NOW NOT GETTING GENERATED UNTIL EAST OF EAU...WHICH
IS WERE HIGHEST RISK OF FOR A BRIEF SHRA WILL EXIST.
OTHERWISE...BKN CU FIELD AROUND 5K FT IS EXPECTED BY THE AFTERNOON
DOWN TO THE TWIN CITIES...WITH A BRIEF MVFR CIG POSSIBLE AT AXN
BETWEEN 14 AND 16Z.
KMSP...FAVORED TAF WIND DIRECTIONS TOWARD THAT OF THE HRRR...WITH
WINDS EXPECTED TO VEER TO THE WEST BY THE AFTERNOON. DO NOT EXPECT
WINDS TO BE CONSISTENTLY NORTH OF 240 UNTIL AFTER 15Z...SO THERE
COULD BE A FEW ISSUES WITH HAVING THE AIRPORT ON THE 30S HERE IN
THE FIRST COUPLE OF HOURS. AFTER THAT...DO EXPECT BKN CIGS...BUT
CAPPING INVERSION LOOKS TO BE LOW ENOUGH THIS AFTERNOON TO LIMIT
ANY SHOWER POTENTIAL. ALSO...BASED ON WINDS ACROSS THE DAKOTAS ALL
NIGHT...LOOKS GOOD TO SEE ANOTHER DAY OF GUSTS UP TO AROUND 30
KTS...EXCEPT THIS TIME WITH A WEST WIND. WILL SEE LIGHTER WINDS
TUESDAY AS HIGH PRESSURE MOVES THROUGH.
OUTLOOK...
.TUE...VFR/SKC. WINDS NW 5-10 KTS.
.WED...VFR WITH BRIEF PERIODS OF MVFR WITH SCTD SHRA/TSRA. WINDS S 10-15
KTS.
.THU...CHC SHRA/TSRA. VFR...EXCEPT MVFR WITH ANY SHRA/TSRA. WINDS
S AROUND 10 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
JVM/MPG
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1220 PM CDT Mon Jun 11 2012
...UPDATED AVIATION DISCUSSION...
.DISCUSSION...
Short Term (Tonight-Wednesday)
Overnight, the focus was on two lines of convection: the leading
line being the advancing gust front and the second line being
focused along the cold front. The showers and thunderstorms along
the gust front continued to weaken through the overnight hours, with
the bit of remnant activity tracking southeast of the Missouri River
by 09Z. The better area of convective activity was focused along the
cold front that was stretching roughly along a line from North
Kansas City to Cameron and Bethany around 09Z. The activity was
remaining well below severe limits with 1000-1500 J/kg MUCAPE, weak
shear, and poor lapse rates present. This line of thunderstorms had
been fairly slow-moving, but has become a bit more progressive toward
the southeast with the help of 20-25kt 850mb winds. This slow
tracking was resulting in higher rainfall rates across extreme
northeast Kansas and northwest Missouri, with some locations likely
accumulating more than one inch of rain within an hour. HRRR shows
the line of thunderstorms stretching along a Kansas City to
Chillicothe line by around 10Z, progressing just south of the
Missouri River by around 13Z. Short range models are in fairly good
agreement that this thunderstorm activity will shift southeast of the
forecast area late this morning, but cannot rule out a few lingering
showers and thunderstorms across central Missouri early this
afternoon.
Winds will shift to the northwest behind the advancing cold front.
However, cold air advection behind the cold front will be limited
today so should see afternoon temperatures still warmer than normal
-- into the middle 80s. High pressure will build in across the
Northern and Central Plains later this afternoon and track toward
the Great Lakes region by the middle of the week, keeping conditions
dry. Temperatures look to be near to slightly above seasonal normals
through Wednesday as winds shift from northeast to southeast with
the eastward-moving surface high.
As the upper level trough over the Northern Plains progresses toward
the northern Great Lakes, a more zonal flow will set up across the
western and central CONUS through mid-week. Models have shown the
potential for a few disturbances to develop within the zonal flow
primarily west of the forecast area across Kansas. Confidence is low
in whether or not any of these impulses will spread enough eastward
to clip eastern Kansas and extreme western Missouri Wednesday and
Wednesday night, so have nothing more than slight chance pops in for
that area.
ACH
Medium Range (Thursday through Sunday)...
Prefer a wait and see approach as it relates to rain chances during
the medium range period. The 00z ECMWF and GFS build mid level
heights, with the ECMWF developing a closed high, across the mid MO
River Valley while a western U.S. trough builds. While it`s
certainly possible a weak vorticity lobe or two will meander across
the Central Plains Thursday or Friday within a chaotic and weak
westerly flow coming out of the Rockies, confidence is low on just
how much convection, if any can make it into the CWA. Agree with the
previous discussion in favoring the drier ECMWF over the relatively
wet GFS. As such can only justify slight chance pops until the end
late Sunday when falling heights across the Plains in response to
the approaching upper trough offers some hope that increasing
dynamics will generate some scattered convection.
A gradual warm up on temperatures and dewpoints continues to look in
order with readings in the upper 80s/90 by the weekend.
MJ
&&
.AVIATION...
For the 18z TAFs: Secondary cold front beginning to push through the
terminals early this afternoon will allow drier air to filter
southward. Scattered strato-cu deck behind this front and ahead of
850 trough will persist into the afternoon hours. Skies will clear by
this evening and remain VFR though the overnight period.
Will need to monitor for the potential of fog development near
daybreak at the terminals as winds turn light. Recent rainfall
combined with these light winds may support development, but
advection of drier air from the northwest will also inhibit
development.
Dux
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
WFO EAX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
633 AM CDT Mon Jun 11 2012
...UPDATED AVIATION DISCUSSION...
.DISCUSSION...
Short Term (Tonight-Wednesday)
Overnight, the focus was on two lines of convection: the leading
line being the advancing gust front and the second line being
focused along the cold front. The showers and thunderstorms along
the gust front continued to weaken through the overnight hours, with
the bit of remnant activity tracking southeast of the Missouri River
by 09Z. The better area of convective activity was focused along the
cold front that was stretching roughly along a line from North
Kansas City to Cameron and Bethany around 09Z. The activity was
remaining well below severe limits with 1000-1500 J/kg MUCAPE, weak
shear, and poor lapse rates present. This line of thunderstorms had
been fairly slow-moving, but has become a bit more progressive toward
the southeast with the help of 20-25kt 850mb winds. This slow
tracking was resulting in higher rainfall rates across extreme
northeast Kansas and northwest Missouri, with some locations likely
accumulating more than one inch of rain within an hour. HRRR shows
the line of thunderstorms stretching along a Kansas City to
Chillicothe line by around 10Z, progressing just south of the
Missouri River by around 13Z. Short range models are in fairly good
agreement that this thunderstorm activity will shift southeast of the
forecast area late this morning, but cannot rule out a few lingering
showers and thunderstorms across central Missouri early this
afternoon.
Winds will shift to the northwest behind the advancing cold front.
However, cold air advection behind the cold front will be limited
today so should see afternoon temperatures still warmer than normal
-- into the middle 80s. High pressure will build in across the
Northern and Central Plains later this afternoon and track toward
the Great Lakes region by the middle of the week, keeping conditions
dry. Temperatures look to be near to slightly above seasonal normals
through Wednesday as winds shift from northeast to southeast with
the eastward-moving surface high.
As the upper level trough over the Northern Plains progresses toward
the northern Great Lakes, a more zonal flow will set up across the
western and central CONUS through mid-week. Models have shown the
potential for a few disturbances to develop within the zonal flow
primarily west of the forecast area across Kansas. Confidence is low
in whether or not any of these impulses will spread enough eastward
to clip eastern Kansas and extreme western Missouri Wednesday and
Wednesday night, so have nothing more than slight chance pops in for
that area.
ACH
Medium Range (Thursday through Sunday)...
Prefer a wait and see approach as it relates to rain chances during
the medium range period. The 00z ECMWF and GFS build mid level
heights, with the ECMWF developing a closed high, across the mid MO
River Valley while a western U.S. trough builds. While it`s
certainly possible a weak vorticity lobe or two will meander across
the Central Plains Thursday or Friday within a chaotic and weak
westerly flow coming out of the Rockies, confidence is low on just
how much convection, if any can make it into the CWA. Agree with the
previous discussion in favoring the drier ECMWF over the relatively
wet GFS. As such can only justify slight chance pops until the end
late Sunday when falling heights across the Plains in response to
the approaching upper trough offers some hope that increasing
dynamics will generate some scattered convection.
A gradual warm up on temperatures and dewpoints continues to look in
order with readings in the upper 80s/90 by the weekend.
MJ
&&
.AVIATION...
For the 12Z TAFs, the showers and thunderstorms that have developed
along the cold front will continue to track southeastward through
central and into southern Missouri this morning. Winds will shift to
the northwest behind this passing front with dry conditions expected
for the remainder of the period as high pressure begins to settle
into the Northern and Central Plains. Some scattered mid-level
clouds are possible through the day before clearing out by later
this afternoon.
ACH
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
WFO EAX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
411 AM CDT Mon Jun 11 2012
.DISCUSSION...
Short Term (Tonight-Wednesday)
Overnight, the focus was on two lines of convection: the leading
line being the advancing gust front and the second line being
focused along the cold front. The showers and thunderstorms along
the gust front continued to weaken through the overnight hours, with
the bit of remnant activity tracking southeast of the Missouri River
by 09Z. The better area of convective activity was focused along the
cold front that was stretching roughly along a line from North
Kansas City to Cameron and Bethany around 09Z. The activity was
remaining well below severe limits with 1000-1500 J/kg MUCAPE, weak
shear, and poor lapse rates present. This line of thunderstorms had
been fairly slow-moving, but has become a bit more progressive toward
the southeast with the help of 20-25kt 850mb winds. This slow
tracking was resulting in higher rainfall rates across extreme
northeast Kansas and northwest Missouri, with some locations likely
accumulating more than one inch of rain within an hour. HRRR shows
the line of thunderstorms stretching along a Kansas City to
Chillicothe line by around 10Z, progressing just south of the
Missouri River by around 13Z. Short range models are in fairly good
agreement that this thunderstorm activity will shift southeast of the
forecast area late this morning, but cannot rule out a few lingering
showers and thunderstorms across central Missouri early this
afternoon.
Winds will shift to the northwest behind the advancing cold front.
However, cold air advection behind the cold front will be limited
today so should see afternoon temperatures still warmer than normal
-- into the middle 80s. High pressure will build in across the
Northern and Central Plains later this afternoon and track toward
the Great Lakes region by the middle of the week, keeping conditions
dry. Temperatures look to be near to slightly above seasonal normals
through Wednesday as winds shift from northeast to southeast with
the eastward-moving surface high.
As the upper level trough over the Northern Plains progresses toward
the northern Great Lakes, a more zonal flow will set up across the
western and central CONUS through mid-week. Models have shown the
potential for a few disturbances to develop within the zonal flow
primarily west of the forecast area across Kansas. Confidence is low
in whether or not any of these impulses will spread enough eastward
to clip eastern Kansas and extreme western Missouri Wednesday and
Wednesday night, so have nothing more than slight chance pops in for
that area.
ACH
Medium Range (Thursday through Sunday)...
Prefer a wait and see approach as it relates to rain chances during
the medium range period. The 00z ECMWF and GFS build mid level
heights, with the ECMWF developing a closed high, across the mid MO
River Valley while a western U.S. trough builds. While it`s
certainly possible a weak vorticity lobe or two will meander across
the Central Plains Thursday or Friday within a chaotic and weak
westerly flow coming out of the Rockies, confidence is low on just
how much convection, if any can make it into the CWA. Agree with the
previous discussion in favoring the drier ECMWF over the relatively
wet GFS. As such can only justify slight chance pops until the end
late Sunday when falling heights across the Plains in response to
the approaching upper trough offers some hope that increasing
dynamics will generate some scattered convection.
A gradual warm up on temperatures and dewpoints continues to look in
order with readings in the upper 80s/90 by the weekend.
MJ
&&
.AVIATION...
Convection percolating along and behind front will continue for the
next few hours over the terminals as the front lays out more east
west. Shear is weak and gust front getting out ahead will keep storms
below severe levels but as new elevated storms develop the terminals
will be in and out of MVFR until around daybreak. Adolphson
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
WFO EAX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1159 PM CDT SUN JUN 10 2012
.UPDATE...
ISSUED AT 1037 PM CDT SUN JUN 10 2012
ISSUED AT 651 PM CDT SUN JUN 10 2012
MADE SOME MINOR CHANGES TO THE POPS FORECAST FOR EAST CENTRAL
MISSOURI CONCERNING THE TIMING OF THE CHANCE FOR POPS. SLIGHTLY
DELAYED TO POPS ARRIVAL OVER EAST CENTRAL MISSOOURI. STRONG CAP
CONTINUES OVER CENTRAL THROUGH SOUTHEAST AND EAST CENTRAL KANSAS
AT THIS TIME. STILL BELIEVE THAT THE LOCAL LSX WRF AND HRRR IN
SOME FORM HAS THE BEST SOLUTIONS COMPARED TO THE NSSL-NCEP WRF
MODEL. HRRR APPEARS TO BE TO SHOW VERY STRONG REFELCTVITY
ORGANIZATION WHICH MIGHT BE SUSPECT GIVEN THE EVENING ENVIRONMENT.
LIKE THE LOCAL WRF THE BEST. STILL BELIEVE MUCH OF THE
PRECIPITATION WILL REMAIN GENERALLY ALONG AND NORTH OF I-70. AS
CONVECTION GENERALLY MOVES ACROSS THE NORTHERN HALF OF MISSOURI IT
WILL HAVE SOME PROBLEMS MAINTAIN LINE STRUCTURE DUE TO WEAK
VERTICAL SHEAR. ALSO WOULD LIKE TO SEE HIGHER CAPE VALUES FOR THIS
TIME OF THE YEAR FOR A DYNAMIC SYSTEM TO EVOLVE. COMPARING CURRENT
CASE TO PREVIOUS LINE CASES THIS EVENING. LINE-TO WEAK BROAD
BOWING REFLECTIVITY STRUCTURE WILL FURTHER WEAKEN AS CONVECTIVE
SYSTEM MOVES INTO EXTREME NORTHEAST MISSOURI AND EAST CENTRAL
SECTIONS OF THE STATE BY 11 TO 13 UTC.
PRZYBYLINSKI
.SHORT TERM...
ISSUED AT 325 PM CDT SUN JUN 10 2012
(TONIGHT)
ISO-SCT SHRA/TSRA MAY CLIP THE SERN CWA LATE THIS AFTN BUT THE BULK
OF ANY PCPN SHOULD REMAIN CLOSER TO THE MID-LEVEL LOW OVER AR/LA/MS
AS IT LIFTS INTO THE TN VALLEY. ADDITIONAL SCT TSRA ARE EXPECTED TO
DEVELOP LATE TONIGHT ALONG A TRAILING COLD FRONT AS IT SINKS SEWD
FROM THE PLAINS TOWARDS THE CWA. PCPN MAY NOT BE VERY WIDESPREAD
GIVEN THE LIMITED DYNAMICS AND LACK OF UPPER LEVEL SUPPORT.
KANOFSKY
&&
.SHORT TERM...
ISSUED AT 325 PM CDT SUN JUN 10 2012
(TONIGHT)
ISO-SCT SHRA/TSRA MAY CLIP THE SERN CWA LATE THIS AFTN BUT THE BULK
OF ANY PCPN SHOULD REMAIN CLOSER TO THE MID-LEVEL LOW OVER AR/LA/MS
AS IT LIFTS INTO THE TN VALLEY. ADDITIONAL SCT TSRA ARE EXPECTED TO
DEVELOP LATE TONIGHT ALONG A TRAILING COLD FRONT AS IT SINKS SEWD
FROM THE PLAINS TOWARDS THE CWA. PCPN MAY NOT BE VERY WIDESPREAD
GIVEN THE LIMITED DYNAMICS AND LACK OF UPPER LEVEL SUPPORT.
KANOFSKY
&&
.LONG TERM...
ISSUED AT 325 PM CDT SUN JUN 10 2012
(MONDAY THROUGH NEXT SUNDAY)
UPPER LEVEL RIDGE WILL GET SUPPRESSED BY MONDAY AS A STRONG
SHORTWAVE PASSES TO OUR N...AND WILL RESULT IN ZONAL FLOW UNTIL
THURSDAY. AT THE SFC...A CDFNT WILL PUSH THRU MAINLY ON MONDAY
AFTERNOON AND EVENING WITH HI PRES THEN DOMINATING THE REGION
TUESDAY THRU WEDNESDAY NIGHT.
MONDAY STILL LOOKS OUR BEST CHC FOR PCPN OVER THE NEXT WEEK... AND
EVEN THEN...IT ISN/T AS MUCH OF A SLAM DUNK AS ONE WOULD THINK.
WHILE THE MOISTURE AHEAD OF THE FRONT SHOULD BE DECENTLY RICH WITH
SFC DWPTS PUSHING 70F...H850 DWPTS BETWEEN 13-16C...AND PWATS AROUND
1.75" WHICH IS NEAR THE 99TH PERCENTILE FOR CLIMO AND THIS SHOULD
RESULT IN A VERY UNSTABLE ATMOSPHERE...LIFTING MECHANISMS DO NOT
LOOK AS GOOD AND SCENARIOS TO BRING THIS ABOUT DEPICTED BY MODELS DO
NOT INSPIRE CONFIDENCE. FIRST...SYNOPTIC SETUP OF CD FROPA WILL
FEATURE /LAND-BETWEEN-THE-LOWS/ WHICH WILL FEATURE WEAK LO LEVEL
CONVERGENCE WITH A RAPID PUNCH OF RIDGING IMMEDIATELY BEHIND. UPPER
LEVEL SUPPORT LOOKS WEAK IF MODEL SIGNALS ARE CORRECT...AND IF
INCORRECT WOULD MEAN JUST MODEL NOISE. IN ADDITION...A COUPLE
EXPICIT 4KM WRF MODELS (BOTH NMM AND ARW) ARE SHOWING CDFNT AND DRY
LINE LIGHTING UP TONIGHT...WITH THE SRN PART REMAINING THE MOST
ACTIVE AND DIVING THRU SWRN MO...PUSHING AN EFFECTIVE BOUNDARY THRU
MUCH OF THE FA BEFORE THINGS FIRE UP AGAIN IN THE FAR ERN FA MONDAY
AFTERNOON. WHILE IT IS HARD TO BUY FULLY INTO THE EXPLICIT
MODELS...THE MESSAGE IS THAT OF NOT HI CONFIDENCE IN RAIN CHCS AS
WELL AS KEEPING IN MIND THE ONGOING MILD-MODERATE DROUGHT IN THE
AREA. HAVE ONCE AGAIN CAPPED POPS AT 50PCT AREAWIDE AND JUST
DIFFERENTIATED IN ROUGH TIMING OF BEST CHCS. CONVECTIVE DEBRIS
CLOUDS AND PCPN CHCS SHOULD KEEP TEMPS IN CHECK ON MONDAY...BUT
OVERALL PREFERRED THE HIGHER MET MOS NUMBERS.
SHOULD SEE DRY WX TUESDAY THRU WEDNESDAY NIGHT ALTHOUGH ORDINARILY
ZONAL FLOW IN JUNE WOULD GIVE ONE CAUSE FOR PAUSE. LO PWATS AND HI
PRES IN CONTROL SHOULD ENSURE THAT...ALTHOUGH THE VACATING SFC HI ON
WEDNESDAY NIGHT MAY LET SOMETHING SLIP THRU WITH BRIEF WINDOW OF
OPPORTUNITY BETWEEN THAT AND RETURN OF UPPER RIDGE...WILL KEEP A
CLOSE EYE ON THAT.
THE UPPER LEVEL RIDGE WILL THEN RETURN IN FORCE THURSDAY THRU NEXT
SUNDAY BRINGING WITH IT A RETURN OF THE HEAT OF COURSE. HAVE MAX
TEMPS AROUND 90F GOING EACH DAY FROM FRIDAY ON...BUT WOULD NOT BE
SURPRISED TO SEE FRIDAY AND SATURDAY 3-4F WARMER. THERE ARE VERY
WEAK SIGNALS FOR RAIN CHCS FOR MUCH OF THIS PERIOD BUT OVERALL
SYNOPTIC PATTERN SHOULD KEEP ANY CONVECTION OF A PULSE NATURE FROM
WEAK SHEAR ENVIRONMENT AND LIMITED TO AFTERNOON HOURS...AND
GENERALLY ISOLATED IN COVERAGE. PROBABILITIES ARE LO ENOUGH TO
LIMIT TO 20PCT OR LESS...AND THUS SILENT ON THE FCST. MODELS
ATTEMPT TO BREAK RIDGE DOWN A BIT ON SUNDAY...BUT BY DIFFERENT
MEANS...BUT RESULT MAY BE THE SAME. HAVE EDGED BACK 30PCT CHC FROM
SATURDAY TO SUNDAY BUT THIS IS EVEN SCALED BACK FROM WHAT MODELS ARE
SHOWING AS SOMETHING DOESN/T QUITE LOOK RIGHT ABOUT IT.
TES
&&
.AVIATION...
ISSUED AT 1141 PM CDT SUN JUN 10 2012
THUNDERSTORMS OVER NORTHWEST MISSOURI WILL CONTINUE MOVING EAST
AND SHOULD BE MOVING INTO CENTRAL AND NORTHEAST MISSOURI BETWEEN
09Z-10Z. UNCERTAIN HOW EXTENSIVE THE COVERAGE WILL BE AS IT MOVES
THROUGH CENTRAL INTO EASTERN MISSOURI AFTER SUNRISE. CURRENT
INDICATIONS ARE THAT IT WILL STILL BE WIDELY SCATTERED TO
SCATTERED COVERAGE SINCE THE STORMS WILL BE MOVING AWAY FROM THE
GREATEST INSTABILITY. THINK WIDELY SCATTERED STORMS WILL CONTINUE
INTO MONDAY AFTERNOON UNTIL THE FRONT MOVES THROUGH THE AREA.
ELSEWHERE AND OTHERWISE...AREAS OF CIGS BETWEEN 2000-3000FT ARE
DEVELOPING OVER SOUTHEAST MISSOURI AND MAY CONTINUE TO SPREAD
NORTH-NORTHEAST ACROSS SOUTHWEST ILLINOIS AND EASTERN SECTIONS OF
THE STL METRO AREA. MVFR CIGS SHOULD LIFT QUICKLY AFTER SUNRISE
AND VFR FLIGHT CONDITIONS WILL PREVAIL OUTSIDE OF THUNDERSTORMS.
SPECIFICS FOR KSTL...
LATEST SATELLITE PICTURES ARE SHOWING A MVFR DECK BETWEEN
2000-3000FT DEVELOPING AROUND KFAM. LOOKS LIKE THE DECK MAY PASS
EAST OF THE TERMINAL...BUT I CAN`T RULE OUT SOME INTERMITTENT MVFR
CIGS BEFORE SUNRISE. ANY MVFR CIGS THAT DO FORM SHOULD BREAK UP
AND LIFT QUICKLY AFTER SUNRISE. STILL EXPECTING THUNDERSTORMS IN
THE VICINITY AFTER 12Z...NOT SURE WHAT THE COVERAGE WILL BE SO
WILL CONTINUE VCTS WORDING INSTEAD OF TEMPO. WIDELY SCATTERED
SHOWERS AND STORMS WILL LIKELY CONTINUE INTO THE
AFTERNOON...WITH THE THREAT FINALLY ENDING WITH THE COLD FRONT
PASSAGE.
CARNEY
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS GLASGOW MT
257 PM MDT MON JUN 11 2012
.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH WEDNESDAY...
A WEAK UPPER RIDGE OVER THE PACIFIC NORTHWEST INTO ALBERTA WILL
MOVE OVER THE NORTHERN ROCKIES TONIGHT INTO TOMORROW. A WEAK
SHORTWAVE WILL UNDERCUT THE UPPER RIDGE ON TUESDAY. ANOTHER
SLIGHTLY STRONGER SHORTWAVE TROUGH WILL ROTATE AROUND THE UPPER
LOW OVER THE GULF OF ALASKA AND MOVE OVER THE NORTHERN ROCKIES
TUESDAY NIGHT INTO WEDNESDAY.
THIS AFTERNOON AND EVENING THE WINDS WILL CONTINUE TO DROP OFF AS
THE PRESSURE GRADIENT RELAXES AS A SURFACE HIGH MOVES IN FROM THE
SOUTHWEST. SO WILL CANCEL THE LAKE WIND ADVISORY WITH THE
AFTERNOON PACKAGE...A FEW HOURS EARLIER THEN EXPECTED. COULD BE
SOME SCATTERED SHOWERS AROUND WITH SOME ISOLATED THUNDERSTORMS
MOVING ACROSS THE REGION THIS EVENING WHICH WAS INDICATED ON THE
LATEST HRRR RUN. THIS ACTIVITY WILL END BEFORE MIDNIGHT SO
DROPPED POPS DOWN TO NOTHING AFTER THAT.
TUESDAY...ADDED SOME SLIGHT CHANCE POPS OVER MY SW ZONES AS THE
WEAK WAVE MOVES ACROSS SOUTHERN MONTANA. MODELS SOUNDING DO SHOW A
SMALL AMOUNT OF ELEVATED CAPE ACROSS THE REGION SO A FEW ISOLATED
STORMS ARE POSSIBLE SO WENT WITH A SLIGHT CHANCE OF THUNDER FOR
TUESDAY AFTERNOON AND EVENING.
TUESDAY NIGHT THROUGH WEDNESDAY...THE SLIGHTLY STRONGER SHORTWAVE
WILL MOVE INTO WESTERN MONTANA WHICH WILL HELP GENERATE SOUTHWEST
FLOW OVER EASTERN MONTANA. THIS WILL HELP TO DESTABILIZE THE MID
LEVELS AHEAD OF THE SHORTWAVE. CAPE VALUES ARE ONCE AGAIN WEAK AND
ELEVATED OTHER THUNDERSTORM PARAMETERS ARE WEAK AS WELL. THE
THINKING AT THIS TIME IS JUST GENERAL THUNDER POSSIBLE FOR
WEDNESDAY AFTERNOON AND EVENING. RSMITH
.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...
THE EXTENDED PERIOD BEGINS WITH AN UPPER LEVEL SHORTWAVE TROUGH
MOVING OVER MONTANA THURSDAY NIGHT. THE ASSOCIATED COLD FRONT
SWINGS ACROSS THE AREA...MEETING MODERATE INSTABILITY...GENERATING
THUNDERSTORMS IN THE EVENING. TIMING IS NOT CERTAIN WITH THIS WAVE
DUE TO DIFFERENCES BETWEEN THE 12Z GFS AND THE 00Z ECMWF. THESE
DIFFERENCES CONTINUE THROUGH THE ENTIRE PERIOD.
ALTHOUGH NOT CERTAIN...THERE APPEARS TO BE A BREAK IN THE ACTION
ON THURSDAY AND FRIDAY WITH A SHORT PERIOD UPPER RIDGE. THIS
RIDGE GETS OVERTAKEN BY THE NEXT UPPER TROUGH LATE FRIDAY. FROM
THIS POINT ON THE MODELS AGREE WITH AN UPPER TROUGH ONLY IN
GENERAL...BUT DIFFER TOTALLY WITH THE EMBEDDED FEATURES. LATE IN
THE SHIFT THE 12Z EC CONTINUES THE DISAGREEMENT WITH THE GFS.
AGREE THE BEST BET IS TO MAINTAIN CHANCE POPS AND COOLER
TEMPERATURES THROUGH THE ENTIRE PERIOD UNTIL BETTER AGREEMENT IS
OBTAINED. SCT
PREVIOUS DISCUSSION...
SHORTWAVE TROUGH EXITS THE AREA WEDNESDAY NIGHT WITH LINGERING
SHOWERS AND THUNDERSTORMS POSSIBLE ESPECIALLY IN THE NORTHEAST.
HIGH PRESSURE SYSTEM AND SHORTWAVE RIDGE WILL BE OVER THE AREA ON
THURSDAY WITH MAINLY DRY WEATHER. THE WESTERN ZONES COULD SEE A
SHOWER OR THUNDERSTORM IN THE AFTERNOON AHEAD OF THE NEXT SYSTEM.
AN UPPER TROUGH WILL BE OVER MONTANA AND NEARBY AREAS OVER THE
WEEKEND AND EARLY NEXT WEEK. THERE ARE DIFFERENCES BETWEEN THE
MODELS ON HOW THE TROUGH WILL BE CONFIGURED...TIMING OF SHORTWAVES
WITHIN THE TROUGH AND WHEN AND WHERE INDIVIDUAL STORMS WILL OCCUR.
NORTHEAST MONTANA WILL SEE RAIN WITH SHOWERS AND THUNDERSTORMS AT
TIMES OVER THE PERIOD BUT MODEL CONFIDENCE IS TOO LOW TO TIME WHEN
RAIN WILL OCCUR AT THIS POINT. PREVIOUS FORECAST IDEA OF A 30 TO
40 POP BROAD-BRUSH LOOKS REASONABLE FOR NOW. FORRESTER
&&
.AVIATION...
VFR. AN UPPER LEVEL RIDGE WILL MOVE ACROSS NORTHEAST MONTANA
TONIGHT WHICH SHOULD END THE THREAT OF SHOWERS AND REDUCE SKY
COVER. IN ADDITION A WEAK SURFACE PRESSURE DIFFERENCE WILL REDUCE
WINDS TO LIGHT AND VARIABLE TONIGHT. ON TUESDAY A WEAK SHORTWAVE
TROUGH NUDGES INTO THE NORTHERN ROCKIES LEADING TO THUNDERSTORMS.
ALTHOUGH NORTHEAST MONTANA WILL DEVELOP MODERATE INSTABILITY...THE
LACK OF LOCAL DISTURBANCES WILL DIMINISH THE THREAT OF
THUNDERSTORMS. WITH A BROAD LEE SURFACE TROUGH...EXPECT WESTERLY
WINDS TO REMAIN LESS THAN 15KTS. SCT
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1226 PM CDT MON JUN 11 2012
.AVIATION... /FOR THE 11.18Z TAF ISSUANCE/
MINIMAL AVIATION CONCERNS THROUGH MID-DAY TUESDAY. FAIR WEATHER
CUMULUS WILL OCCUR OVER NORTHERN NEBRASKA THIS AFTERNOON...BUT
CEILINGS WILL REMAIN VFR. HIGH PRESSURE WILL BUILD INTO THE UPPER
MIDWEST TONIGHT AND TUESDAY WHICH WILL CAUSE WINDS TO DECREASE AND
SHIFT THE NORTH WINDS AROUND TO THE SOUTH BY TUESDAY MORNING. THE
BOUNDARY LAYER IS EXPECTED TO BECOME WELL MIXED AGAIN ON TUESDAY
SO WILL SEE GUSTY CONDITIONS IN THE LATE MORNING AND AFTERNOON.
FORECAST SOUNDINGS SHOWING AN INCREASE IN MOISTURE AT THE MID-
LEVELS SO SHOULD SEE INCREASED CLOUD COVER TUESDAY...HOWEVER WILL
REMAIN VFR.
&&
.PREV DISCUSSION... /ISSUED 838 AM CDT MON JUN 11 2012/
UPDATE...
HRRR AND RAP INDICATE LOWER 80S ACROSS SWRN NEB THIS AFTN. THE
HRRR AND RAP WERE DEAD ON SUNDAY ACROSS THIS AREA SO THE FCST HAS
BEEN UPDATED FOR SLIGHTLY WARMER TEMPS. REST OF FCST OKAY FOR NOW.
PREV DISCUSSION... /ISSUED 300 AM CDT MON JUN 11 2012/
DISCUSSION...
PACIFIC HIGH PRESSURE WILL BUILD EAST INTO THE CNTRL/NRN PLAINS
TODAY. BREEZY NORTHWEST WINDS STARTING THE DAY BEHIND A SECONDARY
COLD FRONTAL PASSAGE...WILL DIMINISH THIS AFTERNOON AS THE HIGH
PRESSURE BUILDS IN. AIRMASS ACROSS THE AREA IS VERY DRY...WITH A
DOWNSLOPE WIND COMPONENT AIDING THE DRYNESS. DEW POINTS GENERALLY
IN THE 30S TODAY...WILL CREATE AFTERNOON RELATIVE HUMIDITY VALUES
IN THE 15 TO 25 PERCENT RANGE. FORTUNATELY WINDS WILL BE
DIMINISHING DURING THE PERIOD OF LOWEST RELATIVE HUMIDITY...SO
FIRE WEATHER HEADLINES ARE NOT EXPECTED TO BE NEEDED.
SOME GULF MOISTURE BEGINS TO RETURN NORTH INTO THE AREA
TUESDAY...BUT REALLY DOESN/T GET INTO FULL SWING UNTIL TUESDAY
NIGHT...WHEN H85 DEW POINTS RISE TO NEAR 14C ON SOUTHERLY LLJ.
MODELS CONTINUE TO INDICATE A DECENT MID LEVEL WAVE WILL INTERACT
WITH THE RETURNING MOISTURE...AND SCATTERED TSTM DEVELOPMENT IS
POSSIBLE DURING THE AFTERNOON IN UPSLOPE ENVIRONMENT ACROSS THE NEB
PANHANDLE/EASTERN WY AND CO. A LITTLE CONCERNED ABOUT THE LACK OF
BETTER MOISTURE AT FIRST...SO WILL KEEP CHANCES SLIGHT TUESDAY
AFTERNOON...AND INCREASE TO LOW CHANCE TUESDAY NIGHT AS STORMS MOVE
EAST INTO AN INCREASINGLY FAVORABLE MOIST/UNSTABLE ENVIRONMENT DUE
TO SOUTHERLY 45 KT LLJ. MID LEVEL WAVE AND CONVECTION SHOULD PUSH
EAST OF THE AREA WEDNESDAY.
A LARGE CLOSED LOW IS EXPECTED TO DEVELOP ACROSS SOUTHWEST CANADA BY
THURSDAY. GFS ENSEMBLE MEAN KEEPS THE LOW INVOF SOUTHWEST CANADA
THROUGH THE UPCOMING WEEKEND. BUILDING HEAT IS EXPECTED THURSDAY
RIGHT THROUGH THE WEEKEND...AS ANY COLD FRONT ASSOCIATED WITH THE
LOW STAYS WELL NORTHWEST OF THE AREA. RAIN CHANCES WILL NOT BE NIL
HOWEVER...AS THE AREA APPEARS TO BE IN A RATHER ACTIVE SOUTHWEST
FLOW ALOFT. LEEWARD TROUGHING DEVELOPS DAILY...AND THIS COULD SERVE
FOR CONVECTIVE DEVELOPMENT. MOISTURE IS IN PLACE...WITH A DECENT
TRAJECTORY OFF THE GULF DURING THE PERIOD. THE CAVEAT HERE IS
POTENTIAL MID LEVEL WARM AIR...WHICH WOULD TEND TO CAP THE
ATMOSPHERE. THIS WAS THE CASE THIS PAST WEEK...AND WON/T BE OVER
AMBITIOUS WITH RAIN CHANCES AT THIS TIME.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
DISCUSSION...TAYLOR
UPDATE...CDC
AVIATION...BROOKS
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
838 AM CDT MON JUN 11 2012
.UPDATE...
HRRR AND RAP INDICATE LOWER 80S ACROSS SWRN NEB THIS AFTN. THE
HRRR AND RAP WERE DEAD ON SUNDAY ACROSS THIS AREA SO THE FCST HAS
BEEN UPDATED FOR SLIGHTLY WARMER TEMPS. REST OF FCST OKAY FOR NOW.
&&
.PREV DISCUSSION... /ISSUED 640 AM CDT MON JUN 11 2012/
AVIATION...
NO FLIGHT RESTRICTIONS ARE FORECAST THROUGH TONIGHT AND INTO
TUESDAY MORNING. SMOKE FROM AT LEAST FOUR FIRES IN COLORADO WILL BE
VISIBLE THROUGH TODAY AND BEYOND. BASED ON THE UPPER LEVEL WINDS...
THE BASE OF THE SMOKE LAYER COULD BE AS LOW AS 7000 FEET AGL.
HOWEVER...IT IS UNLIKELY THAT THE SMOKE WILL PRODUCE A CEILING.
NORTHWEST WIND 300-330 IS EXPECTED TO INCREASE TO 12-18G21-27KT
BY 15Z. WIND WILL THEN CONTINUE THUS UNTIL AFTER 01Z WHEN IT BECOMES
LIGHT AND VARIABLE.
PREV DISCUSSION... /ISSUED 300 AM CDT MON JUN 11 2012/
DISCUSSION...
PACIFIC HIGH PRESSURE WILL BUILD EAST INTO THE CNTRL/NRN PLAINS
TODAY. BREEZY NORTHWEST WINDS STARTING THE DAY BEHIND A SECONDARY
COLD FRONTAL PASSAGE...WILL DIMINISH THIS AFTERNOON AS THE HIGH
PRESSURE BUILDS IN. AIRMASS ACROSS THE AREA IS VERY DRY...WITH A
DOWNSLOPE WIND COMPONENT AIDING THE DRYNESS. DEW POINTS GENERALLY
IN THE 30S TODAY...WILL CREATE AFTERNOON RELATIVE HUMIDITY VALUES
IN THE 15 TO 25 PERCENT RANGE. FORTUNATELY WINDS WILL BE
DIMINISHING DURING THE PERIOD OF LOWEST RELATIVE HUMIDITY...SO
FIRE WEATHER HEADLINES ARE NOT EXPECTED TO BE NEEDED.
SOME GULF MOISTURE BEGINS TO RETURN NORTH INTO THE AREA
TUESDAY...BUT REALLY DOESN/T GET INTO FULL SWING UNTIL TUESDAY
NIGHT...WHEN H85 DEW POINTS RISE TO NEAR 14C ON SOUTHERLY LLJ.
MODELS CONTINUE TO INDICATE A DECENT MID LEVEL WAVE WILL INTERACT
WITH THE RETURNING MOISTURE...AND SCATTERED TSTM DEVELOPMENT IS
POSSIBLE DURING THE AFTERNOON IN UPSLOPE ENVIRONMENT ACROSS THE NEB
PANHANDLE/EASTERN WY AND CO. A LITTLE CONCERNED ABOUT THE LACK OF
BETTER MOISTURE AT FIRST...SO WILL KEEP CHANCES SLIGHT TUESDAY
AFTERNOON...AND INCREASE TO LOW CHANCE TUESDAY NIGHT AS STORMS MOVE
EAST INTO AN INCREASINGLY FAVORABLE MOIST/UNSTABLE ENVIRONMENT DUE
TO SOUTHERLY 45 KT LLJ. MID LEVEL WAVE AND CONVECTION SHOULD PUSH
EAST OF THE AREA WEDNESDAY.
A LARGE CLOSED LOW IS EXPECTED TO DEVELOP ACROSS SOUTHWEST CANADA BY
THURSDAY. GFS ENSEMBLE MEAN KEEPS THE LOW INVOF SOUTHWEST CANADA
THROUGH THE UPCOMING WEEKEND. BUILDING HEAT IS EXPECTED THURSDAY
RIGHT THROUGH THE WEEKEND...AS ANY COLD FRONT ASSOCIATED WITH THE
LOW STAYS WELL NORTHWEST OF THE AREA. RAIN CHANCES WILL NOT BE NIL
HOWEVER...AS THE AREA APPEARS TO BE IN A RATHER ACTIVE SOUTHWEST
FLOW ALOFT. LEEWARD TROUGHING DEVELOPS DAILY...AND THIS COULD SERVE
FOR CONVECTIVE DEVELOPMENT. MOISTURE IS IN PLACE...WITH A DECENT
TRAJECTORY OFF THE GULF DURING THE PERIOD. THE CAVEAT HERE IS
POTENTIAL MID LEVEL WARM AIR...WHICH WOULD TEND TO CAP THE
ATMOSPHERE. THIS WAS THE CASE THIS PAST WEEK...AND WON/T BE OVER
AMBITIOUS WITH RAIN CHANCES AT THIS TIME.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM/EXTENDED...CDC
AVIATION...BROOKS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1007 PM EDT TUE JUN 12 2012
.SYNOPSIS...
A COLD FRONT WILL MOVE SOUTHEAST AND ACROSS THE EASTERN CAROLINAS
WEDNESDAY...MOVING OFFSHORE WEDNESDAY NIGHT. SHOWERS AND
THUNDERSTORMS WILL END AS THE FRONT MOVES OFFSHORE. LOW PRESSURE
SHOULD DEVELOP ALONG THE FRONT THURSDAY...BRINGING NORTHEAST WINDS
AND MILD TEMPERATURES TO THE CAROLINAS THURSDAY INTO SATURDAY. HIGH
PRESSURE WILL BUILD INTO THE AREA FROM THE NORTHEAST EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1005 PM TUESDAY...DECENT CLUSTER OF SHOWERS AND THUNDERSTORMS
EXTENDS ACROSS THE SE NC COASTAL COUNTIES AND THE ADJACENT COASTAL
AND OFFSHORE WATERS. MOVEMENT IS TO THE ENE NEAR 15 MPH. VIA LATEST
KLTX RAINFALL ESTIMATES...LOOK FOR AN ADDITIONAL ONE TENTH TO ONE
QUARTER OF AN INCH...EXCEPT ONE HALF TO 1 INCH FROM ANY OF THE
STRONGER SHOWERS AND STORMS. THIS CLUSTER/AREA SHOULD TRACK NE OF
THE AREA BY MIDNIGHT TO 1 AM.
THE DEEP PLUME OF MOISTURE FROM THE TROPICS IS SLOWLY BEING CUT OFF
AS THE MID-UPPER LEVEL TROF REACHES THE EASTERN CAROLINAS...VIA THE
LATEST NEAR TERM RUC MODEL HOURLY RUNS. AS A RESULT...THE BEST
CHANCES FOR PCPN AND THE ORIENTATION OF OVERNIGHT POPS ACROSS THE
ILM CWA...WILL CONTINUE TO BE GEARED ALONG THE COASTAL COUNTIES AND
ADJACENT COASTAL/OFFSHORE WATERS. THE 5H VORT ACROSS SOUTHERN GA IS
PROGGED TO TRACK OFF THE GA COAST LATE THIS EVENING AND OVERNIGHT
AND SHOULD NOT BE A PROBLEM FOR THE ILM CWA. WILL HAVE TO MAINLY
DEAL WITH THE APPROACH OF FRONTAL DYNAMICS AND ANY SHEARED MID LEVEL
VORTS ACCOMPANYING IT FOR THE CONTINUED POPS OVERNIGHT. TWEAKED MIN
TEMPS UPWARDS BY A DEGREE OR 2 BASED ON LATEST TRENDS AND A PEAK
LOOK AT THE NEW 00Z GUIDANCE.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 PM TUESDAY...THE BAND OF DEEP TROPICAL MOISTURE WILL
BEGIN TO NUDGE OFFSHORE WEDNESDAY AS THE 500 MB UPPER TROUGH
BEGINS TO KICK EAST AND FINALLY OFF THE COAST WEDNESDAY NIGHT.
THE SURFACE COLD FRONT WILL ACCOMPANY THE UPPER TROUGH TO THE COAST
WEDNESDAY AFTERNOON...BUT A WEAK SEABREEZE WILL HOLD UP THE
FRONT`S EASTWARD PROGRESS UNTIL EVENING. THE HIGHEST CHANCES FOR
SHOWERS AND STORMS WEDNESDAY WILL OCCUR NEAR THE COAST WHERE
ENHANCED LOW-LEVEL CONVERGENCE WILL COEXIST WITH THE LINGERING
TROPICAL HIGH-PRECIPITABLE WATER ATMOSPHERE. CONVECTIVE COVERAGE
SHOULD RANGE FROM 50-60 PERCENT ALONG THE COAST TO ONLY 20-30 PERCENT
ALONG AND WEST OF INTERSTATE 95. UNLIKE TODAY...WEDNESDAY`S STORM
MOTION SHOULD BE FROM NORTH TO SOUTH AS THE MID-LEVEL FLOW SHIFTS
BEFORE THE SURFACE FRONT ARRIVES.
DRIER AIR SHOULD OVERSPREAD THE REGION FROM NW TO SE WEDNESDAY
NIGHT WITH MODEL PRECIP WATER VALUES DROPPING FROM ~2.0 INCHES TO
BARELY 0.6 INCHES BY 12Z THURSDAY. MULTIPLE AREAS OF LOW PRESSURE
WILL DEVELOP ALONG THE FRONT WELL OFFSHORE THURSDAY AND THURSDAY
NIGHT. THE MAIN IMPACTS TO LAND WILL BE INCREASING NORTH TO
NORTHEAST WINDS AND ENOUGH COLD ADVECTION TO KEEP TEMPERATURES AND
DEWPOINTS SURPRISINGLY MILD FOR MID-JUNE. ENOUGH ATLANTIC MOISTURE
SHOULD GET ADVECTED BACK ONSHORE LATE THURSDAY AFTERNOON INTO
THURSDAY NIGHT TO SPREAD A BATCH OF LOW CLOUDS INLAND ALONG THE
COAST WITH THE LARGEST IMPACTS EXPECTED AROUND WILMINGTON.
MOS TEMPERATURES LOOK PRETTY GOOD THROUGH THE PERIOD WITH LITTLE
SPREAD SEEN BETWEEN NUMBERS FROM THE GFS...NAM...OR THE
EXPERIMENTAL ECMWF MOS.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 300 PM TUESDAY...SYNOPTIC PATTERN WILL BE CHARACTERIZED BY A
MID-LEVEL RIDGE AXIS EXTENDING FROM THE GREAT LAKES SOUTHWESTWARD TO
THE SOUTHERN PLAINS...AND A MID-LEVEL TROUGH AXIS A FEW HUNDRED
MILES OFF THE CAROLINA COAST. AT THE SURFACE...THIS WILL TRANSLATE
INTO WEDGE SCENARIO AS HIGH PRESSURE EXTENDS SOUTHWARD ALONG THE
EASTERN SIDE OF THE APPALACHIANS...WITH NORTHEASTERLY FLOW KEEPING
TEMPERATURES ON THE COOL SIDE OF CLIMATOLOGY. MODELS SUGGEST THIS
PATTERN WILL PERSIST THROUGH THE EXTENDED PERIOD.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
AS OF 23Z...WIDELY SCATTERED CONVECTION CONTINUES ACROSS THE
AREA...BUT REMAINS WEAK. COASTAL TERMINALS WILL LIKELY SEE ANOTHER
ROUND WITH LESS AREAL COVERAGE EXPECTED AT KLBT AND KFLO. MANY AREAS
RECEIVED RAINFALL TODAY AND MAY SEE IFR CIGS DEVELOP OVERNIGHT IN
THE AREAS THAT RECEIVED THE MOST RAINFALL. THUS BROUGHT IN TEMPO IFR
CONDITIONS THROUGH AROUND 1200 UTC WEDNESDAY. HEATING WILL ALLOW
THE CIGS TO LIFT DURING THE MORNING...BUT SCATTERED CONVECTION IS
EXPECTED TO REDEVELOP WITH THE HEATING WEDNESDAY AFTERNOON.
EXTENDED OUTLOOK...VFR THROUGH THE FORECAST PERIOD.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1005 PM TUESDAY...SCEC WILL BE ALLOWED TO EXPIRE AT MIDNIGHT
FOR THE ILM NC WATERS. UNTIL THE COLD FRONT REACHES THE COASTAL
WATERS WHICH WILL LIKELY BE CLOSER TO DAYBREAK WED...THE SFC PG AND
PATTERN AHEAD OF IT WILL YIELD SW WINDS AROUND 15 KT...OCCASIONALLY
UP TO 20 KT FOR THE LOCAL WATERS OFF CAPE FEAR. AS THE FRONT MOVES
CLOSER WINDS WILL VEER TO THE WSW TOWARD DAYBREAK AND DROP TO 10 TO
15 KT. SIGNIFICANT SEAS WILL RUN 3 TO 4 FT...UP TO 5 FT ACROSS
THE LOCAL WATERS OFF CAPE FEAR THROUGH MIDNIGHT. DOMINANT PERIODS
WILL BE AROUND 6 SECONDS. WIND DRIVEN WAVES WILL DOMINATE SIG SEAS
WITH A CONTINUED UNDERLYING 1 TO 1.5 FT ESE 9-10 SECOND PERIOD
GROUND SWELL.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 PM TUESDAY...A SURFACE COLD FRONT WILL MAKE ITS WAY DOWN
TO THE COAST MORNING WEDNESDAY...BUT IT SHOULD STALL NEAR THE
BEACHES DURING THE AFTERNOON AS A WEAK SEABREEZE HOLDS UP THE
FRONT`S PROGRESS EAST. SCATTERED SHOWERS AND STORMS WILL ACCOMPANY
THE SLOW-MOVING FRONT WEDNESDAY. THE FRONT WILL RESUME ITS
OFFSHORE MOVEMENT DURING THE EVENING AND SHOULD MOVE WELL OFFSHORE
WEDNESDAY NIGHT. THE 12Z NAM HAS COME INTO AGREEMENT WITH
YESTERDAY`S GFS (AND TODAY`S GFS AS WELL) SHOWING THE DEVELOPMENT
OF MULTIPLE CENTERS OF LOW PRESSURE OFFSHORE THURSDAY ALONG THE
FRONT. THE EXACT LOCATION OF THESE LOWS ARE NOT AS IMPORTANT AS THE
OVERALL IMPACT ON TIGHTENING OUR LOCAL PRESSURE GRADIENT THURSDAY
AFTERNOON INTO THURSDAY NIGHT WITH A SUBSTANTIAL INCREASE IN WIND
SPEEDS EXPECTED ALONG THE COAST. OUR LATEST FORECAST INCREASES WINDS
INTO THE 20-25 KT RANGE THURSDAY NIGHT WITH THE POTENTIAL FOR GUSTS
APPROACHING 30 KT LATE. THIS WILL BUILD SEAS FROM A GENTLE 2-3 FT
WEDNESDAY...TO AS HIGH AS 6-8 FEET NORTH AND EAST OF CAPE FEAR LATE
THURSDAY NIGHT.
LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 300 PM TUESDAY...PERSISTENT NORTHEAST FLOW IS EXPECTED OVER
THE WATERS AS SURFACE HIGH PRESSURE EXTENDS SOUTHWARD ACROSS THE
INLAND CAROLINAS...AND A TROUGH LINGERS WELL OFFSHORE. A MODERATE
PRESSURE GRADIENT ACROSS THE WATERS WILL LIKELY KEEP WINDS IN A
15-25 KT RANGE...AND A PERSISTENT FETCH SHOULD ALLOW SEAS TO BUILD
AS HIGH AS 5-7 FT IN THE 10-20 NM RANGE. SMALL CRAFT ADVISORY
THRESHOLDS WILL BE APPROACHED...IF NOT EXCEEDED AT TIMES FRIDAY AND
SATURDAY...ESPECIALLY ACROSS THE NORTH CAROLINA COASTAL WATERS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TRA
NEAR TERM...DCH
SHORT TERM...TRA
LONG TERM...CRM
AVIATION...SRP
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
745 PM EDT TUE JUN 12 2012
.SYNOPSIS...
A COLD FRONT WILL MOVE SOUTHEAST AND ACROSS THE EASTERN CAROLINAS
WEDNESDAY...MOVING OFFSHORE WEDNESDAY NIGHT. SHOWERS AND
THUNDERSTORMS WILL END AS THE FRONT MOVES OFFSHORE. LOW PRESSURE
SHOULD DEVELOP ALONG THE FRONT THURSDAY...BRINGING NORTHEAST WINDS
AND MILD TEMPERATURES TO THE CAROLINAS THURSDAY INTO SATURDAY. HIGH
PRESSURE WILL BUILD INTO THE AREA FROM THE NORTHEAST EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 740 PM TUESDAY...THE DEEP PLUME OF MOISTURE FROM THE TROPICS
IS SLOWLY BEING CUT OFF AS THE MID-UPPER LEVEL TROF REACHES THE
EASTERN CAROLINAS...VIA THE LATEST NEAR TERM RUC MODEL HOURLY RUNS.
AS A RESULT...THE BEST CHANCES FOR PCPN AND THE ORIENTATION OF
OVERNIGHT POPS ACROSS THE ILM CWA...WILL BE GEARED ALONG THE COASTAL
COUNTIES AND ADJACENT COASTAL WATERS. THE 5H VORT ACROSS SOUTHERN GA
IS PROGGED TO TRACK OFF THE GA COAST LATE THIS EVENING AND OVERNIGHT
AND SHOULD NOT BE A PROBLEM FOR THE ILM CWA. WILL MAINLY DEAL WITH
THE APPROACH OF FRONTAL DYNAMICS AND ANY SHEARED MID LEVEL VORT
ACCOMPANYING IT FOR THE CONTINUED POPS OVERNIGHT. MIN TEMPS LOOK ON
TARGET AND SEE NO REASON TO TWEAK AT THIS TIME.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 PM TUESDAY...THE BAND OF DEEP TROPICAL MOISTURE WILL
BEGIN TO NUDGE OFFSHORE WEDNESDAY AS THE 500 MB UPPER TROUGH
BEGINS TO KICK EAST AND FINALLY OFF THE COAST WEDNESDAY NIGHT.
THE SURFACE COLD FRONT WILL ACCOMPANY THE UPPER TROUGH TO THE COAST
WEDNESDAY AFTERNOON...BUT A WEAK SEABREEZE WILL HOLD UP THE
FRONT`S EASTWARD PROGRESS UNTIL EVENING. THE HIGHEST CHANCES FOR
SHOWERS AND STORMS WEDNESDAY WILL OCCUR NEAR THE COAST WHERE
ENHANCED LOW-LEVEL CONVERGENCE WILL COEXIST WITH THE LINGERING
TROPICAL HIGH-PRECIPITABLE WATER ATMOSPHERE. CONVECTIVE COVERAGE
SHOULD RANGE FROM 50-60 PERCENT ALONG THE COAST TO ONLY 20-30 PERCENT
ALONG AND WEST OF INTERSTATE 95. UNLIKE TODAY...WEDNESDAY`S STORM
MOTION SHOULD BE FROM NORTH TO SOUTH AS THE MID-LEVEL FLOW SHIFTS
BEFORE THE SURFACE FRONT ARRIVES.
DRIER AIR SHOULD OVERSPREAD THE REGION FROM NW TO SE WEDNESDAY
NIGHT WITH MODEL PRECIP WATER VALUES DROPPING FROM ~2.0 INCHES TO
BARELY 0.6 INCHES BY 12Z THURSDAY. MULTIPLE AREAS OF LOW PRESSURE
WILL DEVELOP ALONG THE FRONT WELL OFFSHORE THURSDAY AND THURSDAY
NIGHT. THE MAIN IMPACTS TO LAND WILL BE INCREASING NORTH TO
NORTHEAST WINDS AND ENOUGH COLD ADVECTION TO KEEP TEMPERATURES AND
DEWPOINTS SURPRISINGLY MILD FOR MID-JUNE. ENOUGH ATLANTIC MOISTURE
SHOULD GET ADVECTED BACK ONSHORE LATE THURSDAY AFTERNOON INTO
THURSDAY NIGHT TO SPREAD A BATCH OF LOW CLOUDS INLAND ALONG THE
COAST WITH THE LARGEST IMPACTS EXPECTED AROUND WILMINGTON.
MOS TEMPERATURES LOOK PRETTY GOOD THROUGH THE PERIOD WITH LITTLE
SPREAD SEEN BETWEEN NUMBERS FROM THE GFS...NAM...OR THE
EXPERIMENTAL ECMWF MOS.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 300 PM TUESDAY...SYNOPTIC PATTERN WILL BE CHARACTERIZED BY A
MID-LEVEL RIDGE AXIS EXTENDING FROM THE GREAT LAKES SOUTHWESTWARD TO
THE SOUTHERN PLAINS...AND A MID-LEVEL TROUGH AXIS A FEW HUNDRED
MILES OFF THE CAROLINA COAST. AT THE SURFACE...THIS WILL TRANSLATE
INTO WEDGE SCENARIO AS HIGH PRESSURE EXTENDS SOUTHWARD ALONG THE
EASTERN SIDE OF THE APPALACHIANS...WITH NORTHEASTERLY FLOW KEEPING
TEMPERATURES ON THE COOL SIDE OF CLIMATOLOGY. MODELS SUGGEST THIS
PATTERN WILL PERSIST THROUGH THE EXTENDED PERIOD.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
AS OF 23Z...WIDELY SCATTERED CONVECTION CONTINUES ACROSS THE
AREA...BUT REMAINS WEAK. COASTAL TERMINALS WILL LIKELY SEE ANOTHER
ROUND WITH LESS AREAL COVERAGE EXPECTED AT KLBT AND KFLO. MANY AREAS
RECEIVED RAINFALL TODAY AND MAY SEE IFR CIGS DEVELOP OVERNIGHT IN
THE AREAS THAT RECEIVED THE MOST RAINFALL. THUS BROUGHT IN TEMPO IFR
CONDITIONS THROUGH AROUND 1200 UTC WEDNESDAY. HEATING WILL ALLOW
THE CIGS TO LIFT DURING THE MORNING...BUT SCATTERED CONVECTION IS
EXPECTED TO REDEVELOP WITH THE HEATING WEDNESDAY AFTERNOON.
EXTENDED OUTLOOK...VFR THROUGH THE FORECAST PERIOD.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 740 PM TUESDAY...SCEC WILL BE ALLOWED TO EXPIRE AT MIDNIGHT
FOR THE ILM NC WATERS. UNTIL THE COLD FRONT REACHES THE COASTAL
WATERS WHICH WILL LIKELY BE CLOSER TO DAYBREAK WED...THE SFC PG AND
PATTERN AHEAD OF IT WILL YIELD SW WINDS AROUND 15 KT...OCCASIONALLY
UP TO 20 KT FOR THE LOCAL WATERS OFF CAPE FEAR. SIGNIFICANT
SEAS WILL RUN 3 TO 4 FT...UP TO 5 FT ACROSS THE LOCAL WATERS OFF
CAPE FEAR THROUGH MIDNIGHT. DOMINANT PERIODS WILL BE AROUND 6
SECONDS.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 PM TUESDAY...A SURFACE COLD FRONT WILL MAKE ITS WAY DOWN
TO THE COAST MORNING WEDNESDAY...BUT IT SHOULD STALL NEAR THE
BEACHES DURING THE AFTERNOON AS A WEAK SEABREEZE HOLDS UP THE
FRONT`S PROGRESS EAST. SCATTERED SHOWERS AND STORMS WILL ACCOMPANY
THE SLOW-MOVING FRONT WEDNESDAY. THE FRONT WILL RESUME ITS
OFFSHORE MOVEMENT DURING THE EVENING AND SHOULD MOVE WELL OFFSHORE
WEDNESDAY NIGHT. THE 12Z NAM HAS COME INTO AGREEMENT WITH
YESTERDAY`S GFS (AND TODAY`S GFS AS WELL) SHOWING THE DEVELOPMENT
OF MULTIPLE CENTERS OF LOW PRESSURE OFFSHORE THURSDAY ALONG THE
FRONT. THE EXACT LOCATION OF THESE LOWS ARE NOT AS IMPORTANT AS THE
OVERALL IMPACT ON TIGHTENING OUR LOCAL PRESSURE GRADIENT THURSDAY
AFTERNOON INTO THURSDAY NIGHT WITH A SUBSTANTIAL INCREASE IN WIND
SPEEDS EXPECTED ALONG THE COAST. OUR LATEST FORECAST INCREASES WINDS
INTO THE 20-25 KT RANGE THURSDAY NIGHT WITH THE POTENTIAL FOR GUSTS
APPROACHING 30 KT LATE. THIS WILL BUILD SEAS FROM A GENTLE 2-3 FT
WEDNESDAY...TO AS HIGH AS 6-8 FEET NORTH AND EAST OF CAPE FEAR LATE
THURSDAY NIGHT.
LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 300 PM TUESDAY...PERSISTENT NORTHEAST FLOW IS EXPECTED OVER
THE WATERS AS SURFACE HIGH PRESSURE EXTENDS SOUTHWARD ACROSS THE
INLAND CAROLINAS...AND A TROUGH LINGERS WELL OFFSHORE. A MODERATE
PRESSURE GRADIENT ACROSS THE WATERS WILL LIKELY KEEP WINDS IN A
15-25 KT RANGE...AND A PERSISTENT FETCH SHOULD ALLOW SEAS TO BUILD
AS HIGH AS 5-7 FT IN THE 10-20 NM RANGE. SMALL CRAFT ADVISORY
THRESHOLDS WILL BE APPROACHED...IF NOT EXCEEDED AT TIMES FRIDAY AND
SATURDAY...ESPECIALLY ACROSS THE NORTH CAROLINA COASTAL WATERS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TRA
NEAR TERM...DCH
SHORT TERM...TRA
LONG TERM...CRM
AVIATION...SRP
AREA FORECAST DISCUSSION
NWS RALEIGH NC
752 PM EDT TUE JUN 12 2012
.SYNOPSIS...
A COLD FRONT WILL PUSH SLOWLY SOUTHEAST THROUGH THE REGION LATE
TONIGHT AND WEDNESDAY...BRINGING COOLER AND MUCH DRIER CONDITIONS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 230 PM TUESDAY...
OVERVIEW:
A WEAK MID-LEVEL TROUGH CENTERED OVER THE WESTERN CAROLINAS (NEAR
I-77 PER 700 MB 15Z SPC MESOANALYSIS) WILL TRACK SLOWLY EASTWARD
INTO THE CENTRAL CAROLINAS THIS AFTERNOON/EVENING...PROGRESSING TO
THE CAROLINA COAST BY 12Z WED MORNING. IN THE LOWER LEVELS...A
SFC-H85 REFLECTION ATTENDANT THE MID-LEVEL WAVE WILL ALSO PROGRESS
EASTWARD INTO THE CENTRAL CAROLINAS. FURTHER UPSTREAM...A COLD FRONT
EXTENDING SSW FROM THE GREAT LAKES INTO THE WESTERN OH/TN VALLEY AT
15Z THIS MORNING WILL PROGRESS INTO THE SOUTHERN APPALACHIANS BY 00Z
THIS EVENING. THE FRONT WILL SLOW DOWN AND BECOME INCREASINGLY
WEST-EAST ORIENTED TONIGHT...THEN PROGRESS SOUTH THROUGH THE AREA ON
WED AS HIGH PRESSURE STRENGTHENS OVER THE GREAT LAKES AND NORTHERN
MID-ATLANTIC.
PRECIPITATION CHANCES:
DESPITE A VERY MOIST BOUNDARY LAYER WITH SFC DEWPOINTS IN THE LOWER
70S...WEAK MID-LEVEL LAPSE RATES AND EXTENSIVE CLOUD COVER OVER THE
AREA SHOULD TEMPER DIURNAL DESTABILIZATION THIS AFTERNOON ALONG/EAST
OF HWY 1...WHERE 500-1000 J/KG OF MLCAPE IS PROGGED AT BEST. IN THE
WESTERN PIEDMONT...LESS CLOUD COVER AND BETTER INSOLATION WILL LEAD
TO STRONGER DIURNAL DESTABILIZATION...WITH MLCAPE VALUES PROGGED AT
1000-1500 J/KG. BASED ON SPC MESOANALYSIS AND THE LATEST
OBSERVATIONAL DATA...THE LOW/MID-LEVEL TROUGH IN VICINITY OF I-77
OVER THE WESTERN CAROLINAS AT 15Z WILL BE THE PRIMARY FOCUSING
MECHANISM FOR CONVECTION TODAY AS IT PROGRESSES EASTWARD INTO
CENTRAL NC IN THE PRESENCE OF A TROPICAL (PWAT NEAR 2.00") AIRMASS.
15Z VWP DATA FROM SURROUNDING SITES ALREADY SHOW WESTERLY LOW-LEVEL
FLOW AT GSP/RNK/CAE...SUGGESTING THE BEST LOW-LEVEL CONVERGENCE AND
FOCUS FOR CONVECTION TODAY SHOULD REMAIN ALONG AND EAST OF HIGHWAY
1...AND WILL MAINTAIN CATEGORICAL (80%) PRECIPITATION CHANCES IN
THAT AREA. FURTHER WEST THE FORECAST IS MORE UNCERTAIN. ALTHOUGH THE
BEST CONVERGENCE WITH THE LOW/MID-LEVEL TROUGH IS ALREADY IN
VICINITY OF HWY 1...15Z WV IMAGERY SHOWED A SHEAR AXIS PROGRESSING
EASTWARD THROUGH EASTERN KY/CENTRAL TN...AND THE LATEST RAP MODEL
DATA PROGS THIS FEATURE TO PROGRESS INTO THE MOUNTAINS AND FOOTHILLS
LATER THIS AFTERNOON AND EVENING (IN VICINITY OF PEAK HEATING).
ALTERNATELY...DIFFERENTIAL HEATING IN THE PRESENCE OF A VERY MOIST
AIRMASS MAY LEAD TO THE DEVELOPMENT OF ISOLD/SCT CONVECTION IN THE
MOUNTAINS EARLY THIS AFTERNOON...WHICH COULD PROGRESS EAST/SE INTO
THE WESTERN PIEDMONT BY MID TO LATE AFTERNOON VIA 15 KT W/NW
MID-LEVEL FLOW.
THE 00-12Z HIGH-RES CONVECTION ALLOWING MODELS OFFER VARYING
SOLUTIONS WITH REGARD TO CONVECTION THIS AFTERNOON... RANGING FROM
LITTLE MORE THAN ISOLD CONVECTION IN THE WESTERN PIEDMONT TO THE
DEVELOPMENT OF A SW-NE ORIENTED LINE OF CONVECTION FROM CLT-INT AT
20Z THAT PROGRESSES THROUGH ALL OF CENTRAL NC BY SUNSET.
ADDITIONALLY...LARGE MCS`S UPSTREAM OF THE AREA LAST NIGHT MAY HAVE
ALTERED THE MID-LEVELS IN A MANNER NOT CAPTURED WELL BY THE 00-06Z
MODEL RUNS...ADDING FURTHER UNCERTAINTY TO THE PRECIP FORECAST. WITH
THE ABOVE IN MIND...FEEL THAT IT WOULD BE UNWISE TO REDUCE PRECIP
CHANCES MUCH BELOW WHAT HAS BEEN PREVIOUSLY ADVERTISED IN THE
WESTERN PIEDMONT. AFTER SUNSET...EXPECT CONVECTION TO WEAKEN AND
SHIFT SOUTHEAST IN CONCERT WITH THE MID-LEVEL TROUGH...WITH PRECIP
CHANCES DECREASING AND ENDING FROM NW-SE BY OR SHORTLY AFTER
MIDNIGHT AS A DRIER MID-LEVEL AIRMASS PROGRESSES INTO THE AREA.
SEVERE/FLOODING THREAT:
DO NOT ANTICIPATE A THREAT FOR AREA-WIDE FLOODING GIVEN A LACK OF
WIDESPREAD HEAVY RAIN YESTERDAY (ISOLD AREAS GOT 1-2") AND 1-3 HR
FLASH FLOOD GUIDANCE IN THE 2-4" RANGE IN MOST LOCATIONS (EXCLUDING
URBAN AREAS). HOWEVER...GIVEN THE TROPICAL AIRMASS IN PLACE...
RAINFALL RATES WITH CONVECTION THIS AFTERNOON WILL BE ON THE
HIGH-END...AND A LOCALIZED THREAT FOR FLOODING WILL CERTAINLY BE
PRESENT...PRIMARILY IN URBAN AREAS. ALTHOUGH MODERATE INSTABILITY
WILL BE POSSIBLE IN THE WESTERN PIEDMONT THIS AFT/EVE...DEEP LAYER
SHEAR IS PROGGED TO BE NO HIGHER THAN 15-20 KT...AND ORGANIZED
CONVECTION IS NOT EXPECTED. RELATIVELY BETTER INSOLATION IN THE
WESTERN PIEDMONT MAY YIELD 500-750 J/KG OF DCAPE THIS AFTERNOON...IN
THE PRESENCE OF 1.50"+ PWAT VALUES. THIS COMBINATION OF PRECIP
LOADING AND BOUNDARY LAYER EVAP COOLING COULD RESULT IN ISOLD SEVERE
DOWNBURSTS IN THE WESTERN PIEDMONT BETWEEN 300-800 PM.
TEMPERATURES:
EXTENSIVE CLOUD COVER AND SHOWER ACTIVITY WILL KEEP HIGHS TODAY
SIMILAR TO YESTERDAY...IN THE LOWER 80S...OR 81-85F. LOWS TONIGHT
WILL PRIMARILY DEPEND ON THE PROGRESS OF THE COLD (DRY) FRONT
APPROACHING THE AREA FROM THE NORTHWEST. THE BULK OF MODEL GUIDANCE
AGREES THAT THE FRONT SHOULD MAKE PROGRESS INTO THE N/NW PIEDMONT BY
SUNRISE WED...AND WILL INDICATE LOWS RANGING FROM THE MID/UPPER 60S
N/NW TO ~70F SOUTHEAST. -VINCENT
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 245 PM TUESDAY...
WEDNESDAY:
THE MID-LEVEL TROUGH TRACKING EASTWARD INTO CENTRAL NC TODAY IS
PROGGED TO PROGRESS TO THE CAROLINA COAST BY 12Z WED...WITH A MUCH
DRIER MID-LEVEL AIRMASS OVERSPREADING THE AREA. IN THE LOWER
LEVELS...THE SW-NE ORIENTED COLD FRONT LOCATED OVER THE CENTRAL
OH/TN VALLEY THIS AFTERNOON WILL BECOME MORE WEST-EAST ORIENTED AS
IT MOVES INTO THE MID-ATLANTIC TONIGHT. THE FRONT WILL PROGRESS
SOUTHWARD THROUGH CENTRAL NC DURING THE DAY WED AS HIGH PRESSURE
STRENGTHENS OVER THE GREAT LAKES. THE LATEST MODEL GUIDANCE SHOWS
THE LEADING EDGE OF THE FRONT (AND WIND SHIFT TO THE N/NE) OCCURRING
AROUND OR SHORTLY AFTER SUNRISE WED MORNING...HOWEVER...MODEL
GUIDANCE IS IN RELATIVELY GOOD AGREEMENT THAT THE BOUNDARY LAYER
WILL REMAIN RELATIVELY MOIST THROUGH PEAK HEATING WED...WITH THE
BULK OF THE DRIER AIR NOT ADVECTING INTO CENTRAL NC FROM THE
NORTH/NE UNTIL THE LATE AFTERNOON/EVENING. FCST SOUNDINGS SHOW SFC
DEWPOINTS IN THE MID 60S ALMOST EVERYWHERE...WITH UPPER 60S TO NEAR
70F IN SOUTH/SW PORTIONS OF THE AREA. GIVEN THE RESIDUAL MOIST
BOUNDARY LAYER AND GOOD INSOLATION ASSOC/W DRIER MID-LEVELS...MLCAPE
VALUES COULD REACH AS HIGH AS 1000-1500 J/KG DURING PEAK HEATING...
PRIMARILY IN THE SANDHILLS/SW PIEDMONT. THOUGH THE BEST LOW-LEVEL
CONVERGENCE SHOULD BE ALONG OR JUST OFFSHORE THE CAROLINA COAST WED
AFTERNOON...MODEL GUIDANCE INDICATES SHORTWAVE ENERGY PROGRESSING
INTO WESTERN PORTIONS OF THE STATE BY MID/LATE AFTERNOON. IT IS
POSSIBLE THAT ISOLD CONVECTION COULD DEVELOP OVER PORTIONS OF THE
AREA BETWEEN 21-00Z IF SHORTWAVE ENERGY ARRIVES DURING PEAK HEATING
AND/OR PRIOR TO THE ADVECTION OF THE DRIER /MORE STABLE/ LOW-LEVEL
AIRMASS FROM THE NORTH. AT THIS TIME THE SHORTWAVE ENERGY APPEARS TO
ARRIVE A BIT TOO LATE...AND CONSIDERABLE DRY AIR ALOFT WOULD LIKELY
ACT TO HINDER EVEN ISOLD DEVELOPMENT. WILL KEEP PRECIP CHANCES
CONFINED TO A SLIGHT CHANCE SOUTH OF HWY 64 IN THE SANDHILLS/SW
PIEDMONT DURING THE AFTERNOON. WITH MOSTLY SUNNY SKIES AND COLD
ADVECTION OCCURRING CLOSER TOWARD SUNSET EXPECT HIGHS IN THE
MID/UPPER 80S. -VINCENT
WEDNESDAY NIGHT THROUGH FRIDAY:
MUCH DRIER AND COOLER CONDITIONS ARRIVE WEDNESDAY NIGHT AND
THURSDAY...LASTING THROUGH THE WEEKEND. THE MODELS ARE IN GOOD
GENERAL AGREEMENT IN THE DEVELOPMENT OF A WESTERN ATLANTIC UPPER
TROUGH WITH OUR REGION ON THE SUBSIDENCE SIDE OF THE TROUGH
WEDNESDAY NIGHT THROUGH THE END OF THE WEEK. THE MUCH DRIER AIR WILL
BE FELT WEDNESDAY NIGHT AND THURSDAY AS DEW POINTS FALL INTO THE 50S
WITH THE NNE LOW LEVEL FLOW. THE SKIES ARE EXPECTED TO BE MOSTLY
CLEAR WEDNESDAY NIGHT. SOME MIXING WILL CONTINUE WEDNESDAY NIGHT AS
THE HIGH PRESSURE BUILDS SOUTHWARD DOWN THE EASTERN SEABOARD INTO
NC/SC. LOWS MAY BE HELD UP AS WELL BY THE NE FLOW AT 5-10 MPH. WE
WILL LEAN TOWARD THE WARMER NAM GUIDANCE...60-65 FOR LOWS.
THURSDAY...MODELS ALSO SUGGEST A PERIOD OF CLOUDINESS WILL BE LIKELY
AS THE NE FLOW ADVECTS ATLANTIC MOISTURE ACROSS EASTERN VA INTO
CENTRAL NC DURING THE AFTERNOON AND EVENING. THE FORECAST SOUNDINGS
INDICATE PARTLY SUNNY TO MOSTLY CLOUDY SKIES THROUGH THE AFTERNOON
WITH HIGHS 75-82 (NE TO S). AS THE SURFACE HIGH PRESSURE STRENGTHENS
AND MOVES TOWARD THE MID-ATLANTIC STATES THURSDAY INTO THURSDAY
NIGHT...THE SKIES ARE EXPECTED TO BECOME MOSTLY CLEAR/MOSTLY SUNNY.
LOWS WILL DIP INTO THE 55-62 RANGE THURSDAY MORNING...WITH HIGHS
EXPECTED TO HOLD IN THE UPPER 70S TO LOWER 80S. THESE READINGS WILL
BE 5-8 DEGREES BELOW THE MID JUNE NORMALS. -BADGETT
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 220 PM TUESDAY...
AN EXTENDED DRY AND COOL PATTERN FOR MID JUNE.
THE SURFACE RIDGE ALONG THE EAST COAST IS FORECAST TO STRENGTHEN
FRIDAY INTO THE WEEKEND WITH A CONTINUED SUPPLY OF COOL AND DRY AIR
ADVECTION INTO NC. FRI-SUN SHOULD FEATURE MOSTLY CLEAR NIGHTS AND
MOSTLY SUNNY DAYS WITH LOW HUMIDITY. LOWS WILL BE IN THE 50S TO
AROUND 60 (5-10 DEGREES BELOW NORMAL). HIGHS WILL BE IN THE 77-82
RANGE... OR 5-8 DEGREES BELOW NORMAL).
BY MONDAY AND TUESDAY... THERE IS A CHANCE OF SOME RETROGRESSION OF
THE UPPER PATTERN WITH THE MID/UPPER LOW OVER THE WESTERN ATLANTIC
POSSIBLY DRIFTING SLOWLY WESTWARD TOWARD THE EASTERN SEABOARD.
STRONG RIDING IS EXPECTED TO OUR NW OVER THE OHIO VALLEY AND
MIDWEST. THIS WILL LEAD TO A CONTINUED NORTHERLY FLOW ALOFT WITH DRY
CONDITIONS. TEMPERATURES AND HUMIDITIES WILL MODERATE BACK CLOSER TO
MID JUNE NORMALS... YET NOT QUITE ALL THE WAY BACK. LOWS 62-67 WITH
HIGHS IN THE MID TO UPPER 80S.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
AS OF 750 PM TUESDAY...
24 HOUR TAF PERIOD:
AS OF 00Z A SMALL LINE OF THUNDERSTORMS IS MOVING INTO THE PIEDMONT
TRIAD AREA. HAVE TEMPO GROUP FOR THUNDER IN THE TAFS AT KGSO AND
KINT THROUGH 3Z. OUTSIDE OF THE TRIAD...EARLIER RAIN AND THUNDER HAS
EXITED TO THE EAST. WILL WAIT TO SEE HOW THUNDER THREAT TO THE NORTH
AND WEST EVOLVES BEFORE PUTTING ANYTHING INTO THE KRDU...KFAY...AND
KRWI TAFS. EXPECT FOG AND OR LOW STRATUS AT ALL SITES AFTER 3Z AND
CONTINUING UNTIL NEAR SUNRISE. WINDS WILL BE LIGHT AND VARIABLE
OVERNIGHT...EVENTUALLY SHIFTING AROUND TO NORTH NORTHEASTERLY BY
WEDNESDAY MORNING AND MAY TAKE ON A MORE EASTERLY COMPONENT BY THE
AFTERNOON. BROKEN CEILINGS WILL REMAIN THROUGHOUT THE AFTERNOON ON
WEDNESDAY MOSTLY IN THE 3-5 KFT RANGE. A COLD FRONT WILL LINGER
ACROSS SOUTHERN PORTIONS OF THE AREA TOMORROW AFTERNOON WHICH COULD
LEAD TO SOME SHOWER AND THUNDERSTORM ACTIVITY AT KFAY BUT HAVE KEPT
IT OUT OF THE 00Z TAF PACKAGE UNTIL FORECAST CONFIDENCE RISES.
VFR CONDITIONS ARE LARGELY EXPECTED THROUGH THE END OF THE WEEK
HOWEVER SOME MVFR CEILINGS MAY RESULT FROM THE PREVAILING
NORTHEASTERLY FLOW DURING THE EARLY MORNING HOURS EACH DAY THIS
WEEK.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BADGETT
NEAR TERM...VINCENT
SHORT TERM...VINCENT/BADGETT
LONG TERM...BADGETT
AVIATION...ELLIS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
302 PM EDT MON JUN 11 2012
.SYNOPSIS...
A TROPICAL AIRMASS WILL CONTINUE TO BRING OCCASIONAL SHOWERS AND
THUNDERSTORMS TO THE EASTERN CAROLINAS TONIGHT INTO TUESDAY.
LOCALLY HEAVY RAINFALL IS EXPECTED. A WEAK FRONT WILL SLIDE EAST
TO THE COAST WEDNESDAY...WITH DRIER AIR BEHIND THE FRONT LEADING
TO REDUCED CHANCES OF SHOWERS AND STORMS LATER IN THE WEEK.
NORTHEAST WINDS AROUND HIGH PRESSURE TO OUR NORTH WILL BRING
SURPRISINGLY MILD TEMPERATURES THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
AS OF 300 PM WEDNESDAY...SOMEWHAT COMPLICATED SETUP IN PLACE DUE
TO THE JUXTAPOSITION OF LATE-SUMMERLIKE TROPICAL MOISTURE AND
UPPER PIECES OF ENERGY USUALLY ONLY SEEN ON FRINGES OF SUMMER.
MAIN VORT MAX CURRENTLY CLEARLY EVIDENT ON BOTH SAT AND RADAR NR
CLT WITH BAND OF HEAVY SHOWERS/EMBEDDED THUNDERSTORMS ALONG ITS
LEADING EDGE. THIS HEAVY RAIN WILL SWEEP THROUGH WESTERN COUNTIES
OVER THE NEXT COUPLE OF HOURS. THEREAFTER COME A FEW POINTS OF
FCST UNCERTAINTY. FOR ONE...SUBSIDENCE BEHIND THE MAIN VORT SHOULD
SUPPRESS CONVECTION OVER WRN ZONES FOR NEXT SEVERAL HOURS AS THE
VORT MOVES NE AND WEAKENS. SECOND...IT`LL BE INTERESTING TO SEE
HOW THE TRAILING/TRAINING BAND OF SHOWERS PERSISTS AND HOW FAR
EAST THEY PUSH. MODEL GUIDANCE NOT PERFORMING VERY WELL IN THE 1ST
PLACE...BUT SUGGESTS THAT THE MAIN FORCING SHIFTS SOUTH OF THE
REGION ASSOC WITH WEAK JETLET TRAILING THE VORT AS THE MAIN PIECE
WEAKENS NEAR THE CAPE FEAR REGION. FOR WHAT ITS WORTH THE SRF IS
RELUCTANT TO BRING SIGNIFICANT RAIN ASSOC WITH THIS FEATURE ALL
THE WAY EAST TO COASTAL NC COUNTIES DUE TO THE UPPER FEATURE
WEAKENING. GRANTED...THIS IS ALL JUST REALLY TRYING TO FINE-TUNE
POPS...WITH THE LCL SO LOW/500-750M/AREA-WIDE AND THE COLUMN
SATURATED THROUGH SUCH A DEEP LAYER VIRTUALLY EVERY LITTLE RIPPLE
WILL BE ABLE TO GENERATE SHOWERS THAT WILL PUT DOWN APPRECIABLE
RAINFALL. FORECAST THUS STILL BRINGS LIKELY POPS TO NC COAST THIS
EVE. A RELATIVE LULL MAY OCCUR LATE EVENING INTO THE FIRST PART OF
TONIGHT AS ALL OF THESE SHORTWAVES WEAKEN AND/OR MOVE EAST OUT OF
THE AREA. FOCUS WILL THEN SHIFT TO THE IMMEDIATE COASTAL AREAS
WHERE ANOTHER CHAIN OF SHEAR VORTS DEVELOP IN THE FLOW AND LEAD TO
ASCENT.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 3 PM MONDAY...A WET PATTERN WILL CONTINUE INTO TUESDAY WITH
PRECIPITABLE WATER AT OR ABOVE 2.00 INCHES AND THE 500 MB TROUGH
JUST TO OUR WEST. THE BULK OF THE RAINFALL TUESDAY MORNING SHOULD
BE OFFSHORE PERHAPS AFFECTING THE BEACHES...BUT ACTIVITY WILL
SHIFT BACK ONSHORE BY MID TO LATE MORNING WITH SLOW-MOVING HEAVY
SHOWERS AND ISOLATED TSTMS EXPECTED TO SPREAD ALL THE WAY BACK
INTO CENTRAL NC/SC BY EARLY AFTERNOON. PLENTY OF CLOUDS...A NEARLY
SATURATED TROPOSPHERE...AND LITTLE VERTICAL WIND SHEAR SHOULD
REDUCE OUR SEVERE WEATHER POTENTIAL AND LEAVE LOCALIZED RAINFALL-
INDUCED FLOODING AS THE PRIMARY ADVERSE WEATHER POTENTIAL.
ANTECEDENT CONDITIONS ARE NOT TREMENDOUSLY WET OVER THE EASTERN
CAROLINAS: TS BERYL BROUGHT OUR LAST SIGNIFICANT RAINFALL EVENT
OVER 10 DAYS AGO AND ONE-WEEK RAINFALL (NOT COUNTING TODAY) IS
ONLY 5-25% OF NORMAL. FLOODING POTENTIAL IS NOT QUITE HIGH ENOUGH
FOR A FLOOD WATCH AT THIS TIME...BUT WE WILL CONTINUE THE MENTION
OF LOCALIZED FLOODING IN THE HAZARDOUS WEATHER OUTLOOK.
THE 500 MB TROUGH SHOULD EASE ITS WAY TO THE COAST WEDNESDAY
AFTERNOON WITH DRIER MID-LEVEL AIR (1.50 INCH PW) ADVECTING IN ON
LIGHT NW/N WINDS ALOFT DURING THE DAY. THIS IS NEARLY THE SAME
TIMING OF THE SURFACE COLD FRONT AS WELL. THIS SHOULD LEAD TO
GRADUALLY DIMINISHING POPS WITH THE HIGHEST CHANCES OF SHOWERS AND
STORMS WEDNESDAY ALONG THE COAST. THE GFS IS MUCH MORE BULLISH
DEVELOPING SYNOPTIC LOW PRESSURE ALONG THE FRONT WEDNESDAY NIGHT
WHICH WOULD BRING A SOMEWHAT STRONGER NE SURGE DOWN THE COAST WITH
DRIER AND COOLER AIR PENETRATING FARTHER SOUTH INTO SOUTH CAROLINA.
DIURNAL TEMPERATURE RANGES WILL BE RESTRICTED TUESDAY DUE TO CLOUDS
AND RATHER WIDESPREAD SHOWER ACTIVITY. HIGH TEMPERATURES SHOULD
BRIEFLY REACH 84-85 DEGREES ALTHOUGH THIS MIGHT BE FOR ONLY A FEW
MINUTES IN BREAKS BETWEEN SHOWERS. AFTER A HUMID TUESDAY NIGHT WITH
LOWS 69-73...SOMEWHAT DRIER CONDITIONS WEDNESDAY WILL ALLOW HIGHS
INLAND TO REACH THE UPPER 80S. LOWS WEDNESDAY NIGHT SHOULD FALL TO
67-71...ALTHOUGH STRONGER COLD ADVECTION BEHIND OFFSHORE LOW
PRESSURE AS ADVERTISED BY THE 12Z GFS COULD BRING SLIGHTLY COOLER
READINGS.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 300 PM MONDAY...MEDIUM RANGE GUIDANCE CONTINUES TO ADVERTISE
THE MID LEVEL PATTERN DEVELOPING INTO A OMEGA CONFIGURATION FOR
THE WEEKEND. AT THE SURFACE...HIGH PRESSURE WILL BE THE FEATURE OF
FOCUS FOR OUR AREA WITH THE RIDGE AXIS ALIGNED ALONG THE
APPALACHIANS AS LOW PRESSURE REMAINS WELL OFFSHORE. THURSDAY AND
FRIDAY SHOULD BE DRY. IT APPEARS ENOUGH MOISTURE POOLING OCCURS
SATURDAY THROUGH MONDAY TO WARRANT NORTHEAST RESULTANT SEA BREEZE
POPS. OPERATIONAL GFS/MEX NUMBERS ARE QUITE COOL AND OPTED FOR
SLIGHTLY MODIFIED/WARMER HIGHS AND OVERNIGHT LOWS.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 18Z...AIRMASS VERY JUICY WITH PRECIPITABLE WATER VALUES AROUND
TWO INCHES. THIS CREATES MODERATE UNCERTAINTY WITH RESPECT TO TIMING
OF CONVECTION. THE HRRR MODEL DID NOT INITIALIZE WELL WITH THE
PRECIP OVER SOUTHEASTERN NORTH CAROLINA...SO IT MAY NOT HOLD WEIGHT
FOR ACTIVITY THIS AFTERNOON. NEVERTHELESS...IT SHOWS AN AREA OF
ACTIVE CONVECTION MOVING THROUGH THE CWA FROM WEST TO EAST THIS
AFTERNOON...WEAKENING FOR DIURNAL REASONS AS IT NEARS THE COAST.
VISIBILITIES COULD BRIEFLY GO DOWN TO IFR IN THE BRIEF HEAVY RAIN.
OVERNIGHT...EXPECT CONVECTION TO WANE...BUT COULD NOT RULE OUT A
SHOWER AT NEARLY ANY TIME. CEILINGS WILL REMAIN MVFR FOR THE MOST
PART BUT COULD GO IFR INLAND TOWARD MORNING.
TUESDAY...A FRONTAL BOUNDARY APPROACHES FROM THE WEST AS WELL AS A
PRE FRONTAL TROUGH. CONVECTION IS EXPECTED...MAINLY FROM LATE
MORNING ON.
EXTENDED OUTLOOK...CHANCE FOR THUNDERSTORMS/IFR TUESDAY AFTERNOON
THROUGH WEDNESDAY MORNING. OTHERWISE EXPECT VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM MONDAY...HIGH PRESSURE MAINTAINS ITS PRESENCE OFF THE
SOUTHEAST COAST THROUGH THE PERIOD ALTHOUGH IT IS A FAIRLY WEAK
HIGH...ITS MAIN CENTER OFF THE COAST OF NEW ENGLAND AND NOVA SCOTIA.
A PIEDMONT TROUGH WILL GRADUALLY DEVELOP DURING THE NEAR TERM
HOWEVER AND ADD A FEW KNOTS OF WIND SPEED TO THE FCST. THIS BUMP IN
WINDS PAIRED WITH THE SLIGHT INC IN SE SWELL ENERGY WILL YIELD A
FORECAST OF 2 OR 3 TO 4 FT FORECAST FOR ALL ZONES.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 PM MONDAY...MODERATE SOUTH-SOUTHWEST WINDS ARE EXPECTED
TUESDAY IN ADVANCE OF A COLD FRONT THAT WILL MAKE ITS WAY TO THE
BEACHES DURING THE DAY WEDNESDAY. SLOW-MOVING HEAVY SHOWERS AND
ISOLATED TSTMS WILL BE THE MAIN WEATHER STORY AHEAD OF THIS FRONT.
ALTHOUGH IT IS ALWAYS DIFFICULT TO PREDICT WHERE BATCHES OF
CONVECTION WILL BE MORE THAN A FEW HOURS IN THE FUTURE...MODEL
TRENDS HINT AT THE BEST CHANCES ACROSS THE COASTAL WATERS TUESDAY
MORNING...WITH PERHAPS A SECOND MAXIMUM IN COVERAGE LATE TUESDAY
NIGHT. ONCE THE FRONT PUSHES OFFSHORE WEDNESDAY AFTERNOON WINDS
WILL TURN NORTHEASTERLY...WITH CONSIDERABLE MODEL DISAGREEMENT
CONCERNING WHETHER A NORTHEAST SURGE DEVELOPS WITH LOW PRESSURE
DEVELOPING ALONG THE FRONT OFFSHORE. FOR NOW WE HAVE ONLY
INCREASED FORECAST WIND SPEEDS INTO THE 10-15 KT RANGE...BUT THE
12Z GFS WOULD IMPLY SPEEDS IN THE 15-20 KT RANGE WEDNESDAY
NIGHT...BUT STRONGER THAN THE 12Z NAM MODEL.
LONG TERM /THURSDAY THROUGH FRIDAY/...
AS OF 300 PM MONDAY...NORTHEASTERLY FLOW WILL PREVAIL THROUGH THE
PERIOD AS SURFACE HIGH PRESSURE AXIS IS SITUATED ALONG THE
APPALACHIANS. WIND SPEEDS WILL HOVER IN A RANGE OF 10-15 KNOTS
PROBABLY CLOSER TO THE LOWER RANGE MOST OF THE TIME. CAVEAT TO THE
FORECAST WITH THIS TYPE OF SYNOPTIC SCENARIO IS THE EMBEDDED
NUMEROUS SURGES WHICH ARE ALL BUT IMPOSSIBLE TO RECONCILE THIS FAR
OUT IN TIME. SEAS WILL HOVER IN A RANGE OF 2-4 FEET THURSDAY AND
FRIDAY INCREASING TO 3-5 FEET AND POSSIBLY HIGHER INTO FLAG
CRITERIA SATURDAY AS THE FETCH PERSISTS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TRA
NEAR TERM...MBB
SHORT TERM...TRA
LONG TERM...SHK
AVIATION...MBB/DL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
140 PM EDT MON JUN 11 2012
.SYNOPSIS...
SHOWERS AND THUNDERSTORMS WITH TORRENTIAL DOWNPOURS WILL BE ON THE
INCREASE INTO WEDNESDAY AS TROPICAL MOISTURE FEEDS NORTH AHEAD OF A
SLOW-MOVING COLD FRONT. THIS FRONT WILL MOVE ACROSS THE AREA ON
WEDNESDAY. HIGH PRESSURE WILL BUILD DOWN FROM THE GREAT LAKES
THURSDAY AND PERSIST THROUGH THE WEEKEND AS LOW PRESSURE DEVELOPS
OFF THE COAST OF CAPE HATTERAS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM WEDNESDAY...NOT MUCH TO CHANGE AT THIS POINT...JUST
TRYING TO PIN DOWN BEST LOCATION AND TIMING OF PRECIP CHANCES. AGREE
WITH PREV FCST THAT MAIN AREA OF RAINFALL WILL MOVE IN FROM THE
WEST...THE BAND OF SHOWERS CURRENTLY CROSSING THE SAVANNAH RIVER. A
FEW SMALLER SCALE BANDS OF SHALLOW CONVECTION HAVE BROKEN OUT ALONG
APPARENT DIFFERENTIAL HEATING BOUNDARIES...AND THERE IS NO REASON TO
THINK THAT THEY WILL NOT CONTINUE. SUCH FEATURES WILL BE TOUGH TO
TIME BUT ALSO NOT LEAD TO VERY APPRECIABLE PRECIP AMOUNTS. PREVIOUS
DISCUSSION...
AS OF 6 AM MONDAY...A TROPICAL MOISTURE FEED EXTENDING FROM NEAR THE
BAY OF CAMPECHE AND UP THROUGH THE SOUTHEASTERN STATES WILL INCREASE
THE PROBABILITY OF SHOWERS AND THUNDERSTORMS AND HEAVY DOWNPOURS
THIS PERIOD AS A MID-LEVEL RIDGE SLOWLY EXITS THE EASTERN CAROLINAS
AND A SLOW MOVING TROUGH TO OUR W CONTINUES TO APPROACH.
PRECIPITABLE WATER VALUES WILL TOP 2 INCHES AS SSW TO SW LOW LEVEL
JET INCREASES TO 25 TO 30 KT...HIGHEST INLAND FROM THE COAST. MODEST
ISENTROPIC UPGLIDE WILL REMAIN THROUGH THE PERIOD. A WEAK MID-LEVEL
SHORTWAVE TROUGH WILL ADD LIFT AS IT APPROACHES FROM THE SW LATE
TONIGHT. HARD TO RULE OUT PRECIPITATION AT ANY POINT THIS PERIOD.
WILL TREND POPS HIGHER THROUGH THE DAY AND ESPECIALLY TONIGHT AS LOW
LEVEL JETTING AND LIFT INCREASES.
THE POTENTIAL FOR SIGNIFICANT RAINFALL IS THERE GIVEN THE DEEP...
NEARLY SATURATED LAYER THAT DEVELOPS FROM NEAR THE SURFACE THROUGH
20 KFT...MOST PRONOUNCED INLAND. THIS WILL BE ESPECIALLY TRUE LATE
IN THE PERIOD SHOULD CELLS BEGIN TO TRAIN OVER THE SAME GENERAL
AREA. AT THIS TIME...HIGHEST QPF VALUES THIS PERIOD ARE EXPECTED
NEAR THE I-95 CORRIDOR WHERE AMOUNTS COULD REACH 1 TO 2 INCHES. AS
YOU NEAR THE COAST...AMOUNTS SHOULD GENERALLY BE LOWER...ESPECIALLY
ACROSS THE CAPE FEAR REGION WHERE RIDGING WILL ACQUIESCE LAST AND AS
A RESULT POPS WILL BE LOWEST.
DIURNAL RANGE SHOULD BE LIMITED DUE TO DEEP MOISTURE AND ABUNDANCE
OF CLOUD COVER. HIGHS WILL BE ABOUT TO SLIGHTLY BELOW NORMAL. LOWS
WILL BE ABOVE NORMAL...LOWER TO MID 70S. IT WILL FEEL RATHER HUMID
THROUGH THE PERIOD WITH DEWPOINTS AS HIGH AS THE LOWER 70S.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 3 AM MONDAY... DEEP MOIST SOUTHERLY FLOW WILL BE IN PLACE
ON TUESDAY AHEAD OF AN APPROACHING COLD FRONT. MEANWHILE SHORTWAVE
TROUGH TRACKING UP FROM THE GULF COAST WILL MOVE EAST ACROSS THE
CAROLINAS TUES INTO WED AS A NORTHERN STREAM TROUGH PUSHES THIS
COLD FRONT EAST INTO AND THROUGH THE COASTAL CAROLINAS WED. THE H5
TROUGH WILL PROVIDE ENHANCED SUPPORT FOR SHWR/TSTM ACTIVITY IN A
MOIST AND UNSTABLE ENVIRONMENT. GFS/NAM SHOWING BEST LIFT AND
MOISTURE TUES AFTN THROUGH TUES NIGHT AND SHIFTING OFF THE COAST
BY WED AFTN. PCP WATER VALUES INCREASE UP TO 2.25 INCHES AHEAD AND
ALONG COLD FRONT TUES AFTN THROUGH TUES NIGHT. GFS SHOWS MORE OF A
CLEAN PASSAGE OF FRONT EARLY WED BUT NAM SHOWS SEA BREEZE KICKING
IN ON WED WITH MOISTURE LINGERING ALONG THE COAST AND HOLDING OFF
FROPA UNTIL LATER IN THE DAY.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 3 AM MONDAY...MODELS CONTINUE TO SHOW DEVELOPING LOW
PRESSURE OFF THE HATTERAS COAST ON THURS. THIS MAY HELP TO THROW
AROUND SOME MOISTURE ON BACK END...BUT OVERALL EXPECT DRIER HIGH
PRESSURE TO BUILD DOWN FROM THE GREAT LAKES INTO THE CAROLINAS
THURS THROUGH THE WEEKEND. IN THE MID TO UPPER LEVELS...H5 RIDGE
BUILDS UP THROUGH THE GREAT LAKES HEADING INTO THE WEEKEND WHILE
MID TO UPPER TROUGH MAY DIG SOUTHWESTWARD FROM THE ATLANTIC WATERS
PRODUCING SOME UNCERTAINTY OVER THE WEEKEND. FOR NOW WILL SHOW
DRIER AIR BUILDING IN FOR THURS BUT WILL ADD SOME LOW END POPS
BACK IN FORECAST MAINLY OVER COASTAL WATERS AND JUST ALONG THE
COAST FRI THROUGH THE WEEKEND DUE TO UNCERTAINTY WITH THIS LOW.
TEMPS WILL RUN INTO THE 80S DURING THE DAY AND IN THE 60S AT
NIGHT.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 18Z...AIRMASS VERY JUICY WITH PRECIPITABLE WATER VALUES AROUND
TWO INCHES. THIS CREATES MODERATE UNCERTAINTY WITH RESPECT TO TIMING
OF CONVECTION. THE HRRR MODEL DID NOT INITIALIZE WELL WITH THE
PRECIP OVER SOUTHEASTERN NORTH CAROLINA...SO IT MAY NOT HOLD WEIGHT
FOR ACTIVITY THIS AFTERNOON. NEVERTHELESS...IT SHOWS AN AREA OF
ACTIVE CONVECTION MOVING THROUGH THE CWA FROM WEST TO EAST THIS
AFTERNOON...WEAKENING FOR DIURNAL REASONS AS IT NEARS THE COAST.
VISIBILITIES COULD BRIEFLY GO DOWN TO IFR IN THE BRIEF HEAVY RAIN.
OVERNIGHT...EXPECT CONVECTION TO WANE...BUT COULD NOT RULE OUT A
SHOWER AT NEARLY ANY TIME. CEILINGS WILL REMAIN MVFR FOR THE MOST
PART BUT COULD GO IFR INLAND TOWARD MORNING.
TUESDAY...A FRONTAL BOUNDARY APPROACHES FROM THE WEST AS WELL AS A
PRE FRONTAL TROUGH. CONVECTION IS EXPECTED...MAINLY FROM LATE
MORNING ON.
EXTENDED OUTLOOK...CHANCE FOR THUNDERSTORMS/IFR TUESDAY AFTERNOON
THROUGH WEDNESDAY MORNING. OTHERWISE EXPECT VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM MONDAY...FAIRLY STEAD SET OF CONDITIONS THROUGH THE
DAY TO BRING QUIET WEATHER FOR THE MOST PART. SOME LOW LEVEL JETTING
WILL DEVELOP OVER THE LANDMASS...THE COASTAL WATERS WILL BE ON THE
EASTERN PERIPHERY OF THIS JET LEADING TO A FEW KTS INCREASE IN
SSWRLY FLOW. SEAS 2.5 TO 3 FT AT THE BUOYS WITH PEAK PD AT 5 SEC. A
SMALL 10 SEC SWELL SHOWING UP AS WELL. BOTH WAVE COMPONENTS WILL
CONTINUE AS-IS THROUGH THE PERIOD. PREVIOUS DISCUSSION...
AS OF 6 AM MONDAY...A SOUTH TO SSW FLOW WILL REMAIN ACROSS THE
WATERS AHEAD OF A SLOW MOVING TROUGH APPROACHING FROM THE W. LOW
LEVEL JETTING THIS PERIOD WILL BE STRONGEST LATE TONIGHT WHEN WINDS
COULD REACH 15 TO 20 KT. SEAS WILL HOLD IN THE 2 TO 4 FT RANGE
THROUGH THE DAY WITH PERHAPS SOME 5 FOOTERS CREEPING INTO THE
OUTERMOST WATERS LATE TONIGHT AS WINDS BEGIN TO INCREASE. A 9 TO 10
SECOND SE SWELL WILL PERSIST THROUGH THE PERIOD.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 3 AM MONDAY...GRADIENT TIGHTENS AS COLD FRONT MOVES THROUGH
THE CAROLINAS TUES INTO WED. SOUTHERLY WINDS WILL REACH UP TO 20
KTS AHEAD OF THE FRONT. THIS WILL PUSH SEAS UP TO 3 TO 5 FT LATE
TUES. THE COLD FRONT SHOULD CLEAR THE COASTAL WATERS ON WED WITH
NORTHERLY FLOW DEVELOPING BEHIND IT. THE DIMINISHING OFF SHORE
FLOW WILL ALLOW SEAS TO RELAX DOWN TO 3 FT OR LESS BY WED NIGHT.
LONG TERM /THURSDAY THROUGH FRIDAY/...
AS OF 3 AM MONDAY...LIGHT NORTHERLY FLOW AROUND 10 TO 15 KTS ON
THURSDAY MAY INCREASE UP TO 15 TO 20 KTS ON FRIDAY AS GRADIENT
TIGHTENS BETWEEN HIGH PRESSURE BUILDING DOWN FROM THE GREAT LAKES
AND LOW PRESSURE DEVELOPING OFF THE HATTERAS COAST. SEAS MAY
INCREASE UP TO 4 TO 5 FT IN THE OUTER WATERS FRI INTO TE WEEKEND
AND POSSIBLY HIGHER IF LOW PRESSURE DEEPENS OFF THE COAST. THERE
IS SOME UNCERTAINTY AS TO THE STRENGTH AND LOCATION OF THIS
DEVELOPING LOW PRESSURE OFF THE CAROLINA COAST HEADING INTO THE
WEEKEND AND THEREFORE WILL REMAIN MORE CONSERVATIVE WITH SEA
HEIGHTS FOR NOW. WNA MODEL SHOWS SEAS SHOOTING UP ON FRI TO NEAR
SCA THRESHOLDS IN OUTER WATERS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...MBB
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...43
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
342 PM EDT MON JUN 11 2012
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE FORECAST AREA LATE TONIGHT AND
TUESDAY MORNING. HIGH PRESSURE WILL BUILD IN OVER THE GREAT LAKES WEDNESDAY
AND THEN MOVE SLOWLY EAST THROUGH THE REST OF THE WORK WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
A VERY TOUGH FORECAST MAINLY TO DO WITH THE COVERAGE. SOME LIGHT
SHOWERS WILL EXIT THE NORTHEAST PORTION OF THE FORECAST AREA THIS
EVENING. SOME OF THE MODELS TRY TO INDICATE MORE SHOWERS AND
THUNDERSTORMS DEVELOPING OVER THE EXTREME EASTERN PORTION OF THE
FORECAST AREA LATE THIS EVENING. WENT ALONG WITH THAT BUT VERY
MUCH ON THE EDGE.
FOR NORTHWEST OHIO...SOME SHOWERS AND THUNDERSTORMS DEVELOPING
OVER SOUTHWEST OHIO THAT WILL MOVE NORTHEAST THIS EVENING. THE MCS
OVER MISSOURI AND ILLINOIS DOESN`T SEEM LIKE IT WILL BE A PROBLEM
FOR THE AREA. THE HRRR TRIES TO DEVELOP THIS...WHICH MAY BE OK
WITH A SHORT WAVE MOVING ACROSS THE REGION TONIGHT WITH THE COLD
FRONT. ON THE EDGE ABOUT HOW MUCH THUNDER ACTIVITY WILL OCCUR WITH
THE AIRMASS NOT THAT UNSTABLE.
QPF AMOUNTS SHOULD NOT BE THAT HIGH...WILL HAVE TO WATCH ANY SLOW
MOVING CONVECTION.
WENT TOWARD THE WARMER GUIDANCE FOR LOWS BECAUSE OF CLOUDS AND NOT
WIDESPREAD PRECIPITATION.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
ON THE EDGE HOW MUCH ACTIVITY WILL OCCUR TUESDAY WITH THE FRONT
MOVING THROUGH BY EARLY AFTERNOON. FOLLOWED PREVIOUS FORECAST
WHICH SEEMED REASONABLE. CLOUDS SHOULD DECREASE FROM THE WEST.
OTHERWISE HIGH PRESSURE BUILDING IN FOR THE REMAINDER OF THE
PERIOD. THE LAKE AND 850 MB TEMPERATURE DIFFERENCE SHOULD NOT BE
THAT EXTREME TO CAUSE LAKE EFFECT OR LAKE INDUCED CLOUDS... EXCEPT
MAY BE AROUND DAYBREAK WEDNESDAY WHEN THE DIFFERENCE WILL BE NEAR
10 C.
USED A BLEND OF GUIDANCE FOR THE LOWS AND HIGHS. TENDED TOWARD
COOLER ESPECIALLY FOR NIGHT TIME READINGS.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
FOR THOSE WANTING RAIN...THIS IS NOT A GOOD LONG TERM FORECAST.
RIDGE REMAINS NEARLY STATIONARY OVER THE REGION. MUCH OF THE HEAT
WILL BE TO OUR WEST THROUGH THE WEEKEND SO OUR TEMPERATURES SHOULD
BE IN THE 80S. POSSIBLY A LITTLE WARMER EARLY NEXT WEEK IF THE RIDGE
SHIFTS A LITTLE MORE EAST. HAVE GONE A FEW DEGREES ABOVE GUIDANCE
SINCE LATELY WE HAVE BEEN WARMING BETTER THAN THE CLIMO WEIGHTED
GUIDANCE IS SUGGESTING. WE ARE GETTING DRIER AND WE HAVE A LONG JUNE
DAY TO WARM. AFTERNOON POP-UP SHOWER/TS CHANCES DO NOT EVEN LOOK
THAT GOOD.
&&
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
LIGHT SHOWERS SLOW TO MOVE INTO CENTRAL AND EASTERN PORTIONS OF
THE AREA...BUT THEY WILL. MVFR CEILINGS ASSOCIATED WITH THESE
SHOWERS. CU HAVE GOTTEN A LITTLE BUBBLY OVER INDIANA AND TOL/FDY
MAY SEE AN ISOLATED TS AROUND THIS AFTERNOON. A LOT OF QUESTION AS
TO WHAT WILL DEVELOP THIS EVENING/OVERNIGHT. WILL STILL HAVE A
CHANCE OF SOME EMBEDDED TS AND SCATTERED SHOWERS WITH THE COLD
FRONT MAKING ITS WAY ACROSS THE AREA TOWARD SUNRISE/EARLY MORNING.
SOME GUIDANCE IS WANTING TO GO AS LOW AS IFR WITH VSBY AND/OR CIGS
OVERNIGHT. NOT SURE SO HAVE GONE WITH A MORE CONSERVATIVE MVFR
OVERNIGHT. CLEARING TUESDAY MORNING/EARLY AFTERNOON. SOUTH FLOW
THROUGH TONIGHT...WEST-NORTHWEST TUESDAY AFTER THE FRONT.
.OUTLOOK...NON VFR...NONE.
&&
.MARINE...
LAKE LOOKS LIKE IT WILL GET MIXED UP OVER THE NEXT FEW DAYS AS COLD
AIR ADVECTION NORTHERLY FLOW DEVELOPS. LOOKING AT POSSIBLE SMALL
CRAFT ADVISORIES BY TUESDAY NIGHT. THE EVENT WILL BE SHORT LIVED AS
WINDS BEGIN TO DIMINISH ON WEDNESDAY. HIGH PRESSURE FINALLY BECOMES
STATIONARY OVER THE EAST COAST AND SETS UP A LIGHT SOUTHERLY
COMPONENT TO THE WIND. GENERALLY LIGHT FLOW IS EXPECTED THROUGH THE
REST OF THE PERIOD.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KIELTYKA
NEAR TERM...KIELTYKA
SHORT TERM...KIELTYKA
LONG TERM...OUDEMAN
AVIATION...OUDEMAN
MARINE...LOMBARDY
AREA FORECAST DISCUSSION
NWS NORMAN OK
428 PM CDT MON JUN 11 2012
.DISCUSSION...
THE BIGGEST CHALLENGES ARE SEVERE THUNDERSTORM AND RAIN CHANCES
THROUGH WEDNESDAY.
THROUGH 10 PM CDT TONIGHT...BELIEVE THE BEST CHANCES FOR SEVERE
STORMS WILL OVER WESTERN NORTH TEXAS AND POSSIBLY FAR SOUTHERN
OKLAHOMA NEAR A SURFACE BOUNDARY...WHERE KEPT 20/30 PERCENT
CHANCES. STORMS WERE DEVELOPING NEAR ABILENE TEXAS WHERE THE CAP
HAS BEEN BROKEN AND WILL MOVE EAST AND POSSIBLY NORTHEAST. WITH
THE AIR BEING UNSTABLE WITH SOME SHEAR...THINK LARGE
HAIL...POSSIBLY AS LARGE AS BASEBALLS...AND DAMAGING WIND OF 65
MPH OR GREATER WILL BE THE MAIN HAZARDS. MOST OF THESE STORMS WILL
STAY SOUTH OF THE FORECAST AREA. NOTICED THE LATEST HRRR RUNS
INDICATED ISOLATED DEVELOPMENT EAST OF I-35...SO KEPT 20 PERCENT
IN THESE AREAS...THOUGH CONFIDENCE OF DEVELOPMENT REMAINS QUITE
LOW DUE TO STRONG CAPPING.
AFTER 10 PM CDT TONIGHT...KEPT RAIN CHANCES SOUTH OF A CLINTON TO
OKLAHOMA CITY TO SWEETWATER LINE. ADDITIONAL STORMS MAY DEVELOP
NEAR THE LINE MENTIONED ABOVE BETWEEN 10 PM AND 4 AM AS LATEST
MODELS INDICATED THE MID LEVEL CAP WEAKENING WITH 700 MB
TEMPERATURES COOLING TO +9/10C. WITH ABUNDANT INSTABILITY AND A
GOOD AMOUNT OF SHEAR...A FEW STORMS MAY BE SEVERE WITH LARGE
HAIL...POSSIBLY VERY LARGE...AND DAMAGING WIND. THE FOCUS FOR
LIFT APPEARS TO BE WEAK...SO WIDESPREAD SEVERE SEEMS UNLIKELY.
LOCALLY HEAVY RAINFALL MAY BE POSSIBLE AS WELL.
TUESDAY...KEPT RAIN CHANCES ACROSS MUCH OF THE AREA WITH THE
HIGHEST CHANCES OVER SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS
WHERE BEST MOISTURE AND INSTABILITY ARE FORECAST. SOME STORMS
MAY BE SEVERE WITH LARGE HAIL AND DAMAGING WIND...MAINLY DURING
THE LATE AFTERNOON AND EVENING HOURS...THOUGH LARGE HAIL THREAT
MAY BE LOWER COMPARED TO TONIGHT.
WEDNESDAY INTO THURSDAY...KEPT LOWER CHANCES FOR SHOWERS AND
STORMS OVER THE AREA. CANNOT RULE OUT A FEW SEVERE STORMS
BOTH DAYS.
FRIDAY THROUGH NEXT MONDAY...HOTTER AND DRIER WEATHER
IS EXPECTED. A FEW STORMS MAY BE POSSIBLE DURING THIS TIME
FRAME...BUT DID NOT MENTION DUE TO LOW CONFIDENCE.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 68 85 66 86 / 20 20 40 30
HOBART OK 64 87 67 89 / 20 40 40 30
WICHITA FALLS TX 69 88 71 91 / 40 30 50 30
GAGE OK 55 84 62 88 / 0 20 40 30
PONCA CITY OK 60 86 61 86 / 0 0 20 30
DURANT OK 71 87 70 88 / 50 30 40 30
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
02/17
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
401 PM EDT MON JUN 11 2012
.SYNOPSIS...
A FRONTAL SYSTEM WILL APPROACH FROM THE WEST AND GENERATE
WIDESPREAD SHOWERS AND THUNDERSTORMS FOR LATE TONIGHT AND
TUESDAY. THE COLD FRONT WILL PASS THROUGH TUESDAY NIGHT. THIS
FRONT MAY STALL OUT NEAR THE MID ATLANTIC COAST FOR THE MIDDLE
AND LATTER PART OF THIS WEEK DELAYING THE EXIT OF CLOUDS AND
SHOWERS OUT OF THE EASTERN HALF OF PENNSYLVANIA.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
MSTR ALOFT IS THICKENING UP AND DIURNAL CU IS FORMING/FILLING IN.
THE LOW CRUD IN THE EAST IS GONE. THICKER LINE OF CU FORMING FROM
YORK TO STATE COLLEGE COULD MAKE ISOLD SHRA BEFORE SUNSET. THE MESO
MDLS LIKE THE HRRR AND RUC DO GENERATE SOME RAINFALL THROUGH THE
CONVECTIVE PARAM. SHOWERS ALSO MOVING THRU FAR WRN PA HAVE A
DISTINCT LACK OF LTG DESPITE LOW STABILITY. EXPECT THESE SHOWERS
TO SLIDE TO THE WEST AND AFFECT THE FAR WRN ZONES THIS EVENING.
RAIN WILL NOT BE HEAVY AT ALL...WITH JUST A TENTH OR SO BEFORE
MIDNIGHT. WILL STILL MENTION SLIGHT CHC T FOR THE REGION WITH
STABILITY LOW. MOST OF THE PRECIP WILL WAIT UNTIL AFTER MIDNIGHT
WHEN THE HEIGHTS START TO DROP FASTER. PWATS CLIMB MORE THAN AN
INCH THRU SUNRISE AND THE MDL SOUNDINGS DECIDEDLY MOIST-ADIABATIC
FOR LATER TONIGHT...SO HEAVY RAIN FROM ANY CONVECTION IS POSSIBLE.
SKY COVER WILL BECOME 100PCT THIS EVENING AND EARLY TONIGHT.
THUS...TEMPS SHOULD NOT FALL FAR BELOW THE MID 60S.
FFG AND FFH NUMBERS ARE PRETTY LOFTY - ON THE ORDER OF 2.5 TO 3.5
INCHES IN 3 HRS...SO IT WOULD NEED TO BE MUCH HEAVIER RAIN THAN
EXPECTED TO CREATE FLOODING PROBLEMS. THE DURATION OF THE EVENT
AND PROGRESSIVE NATURE OF THE TROUGH AND FRONT ARGUE AGAINST ANY
FLOOD WATCHES.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
CATEGORICAL POPS ARE STILL IN ORDER THROUGH ALL OF TUESDAY AND
INTO TUESDAY EVENING. STABLE PRECIP SHOULD DOMINATE OVER
CONVECTIVE FORCING. LLJET IS NOT STRONG AT ALL. SHEAR ALSO ONLY
WEAK TO MODERATE. HOWEVER...SPC DOES MENTION THE AREA IN THE DAY2
OUTLOOK. WILL KEEP THE MENTION OF THUNDER IN BUT FOREGO MENTIONS
OF GUSTY WINDS OR HAIL. I THINK IT WILL BE HARD TO GET THE CLOUDS
OUT OF THE WAY LONG ENOUGH AND MATCH UP THE TIMING OF UPPER
FORCING OR THE COLD FRONT WITH THAT POSSIBLE WINDOW OF STRONGER
SFC HEATING AND DESTABILIZATION.
THE HIGH PRECIP WATER WILL NOT BE TAPPED VERY EFFECTIVELY WITHOUT
WIDESPREAD UPRIGHT CONVECTION TO TAP INTO IT. OVERALL...A GENERAL
1 INCH OF PRECIP IS LOOKING LIKE THE STORM TOTAL. EXPECT SLIGHTLY
LOWER AMOUNTS TO THE WEST AND HIGHER AMOUNTS IN THE EAST.
AGAIN...THOSE AMOUNTS SHOULD NOT RAISE EYEBROWS WITH VEGETATION
FULLY GROWN AND STREAM FLOWS AROUND NORMAL.
TIMING OF THE FROPA LOOKS LIKE IT WILL BE A BIT QUICKER THAN PREV
FCSTS...WITH WINDS SHIFTING TO THE WEST LATE TUES AFTN IN THE WEST
AND IN THE EAST BY MIDNIGHT. THUS...WILL KEEP POPS HIGH FOR THE
DAYLIGHT HRS...BUT TAPER THEM OFF COMPLETELY FROM WEST TO EAST
BEFORE SUNRISE WED. THE FRONT ITSELF WILL HANG BACK BEHIND THE
MAIN SHIELD OF PRECIP AND GENERATE SOME LOW-TOPPED SHOWERS AS IT
MOVES THROUGH. MAXES WILL BE IN THE 70S OVERALL WITHOUT SIG BREAKS
IN THE SKY COVER. DRY AIR FINALLY WORKS IN TO THE WEST TUES NIGHT
AS THE STRONGEST SHORT WAVE PUSHES THROUGH. CLEARING - IN THE WEST
AT LEAST - MAY ALLOW FOG TO FORM AS TEMPS DIP CLOSE TO 50 IN THE
WRN MTS AND MID 50S TO NEAR 60 IN THE CENTRAL AND EAST. BUT WIND
AND DRYING AIRMASS MAY NEGATE THAT AS WELL.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
THE CFRONTAL BOUNDARY WILL HAVE PUSHED THE DEEP MOISTURE EAST OF
THE AREA TO BEGIN THE PERIOD. HOWEVER...AN UPPER LOW FCST TO CUT-
OFF OVER THE NORTH ATLANTIC /FOLLOWED BY A DEVELOPING REX BLOCK/
MAY HOLD THE BOUNDARY/TROFFINESS ALONG THE MID ATLANTIC SEABOARD
FOR SEVERAL DAYS MORE. THIS WILL KEEP AT LEAST A LOW POTENTIAL FOR
SOME SHOWERS AND COOLER TEMPERATURES ACROSS THE EASTERN PARTS OF
CENTRAL PA...AS A SLIGHTLY ANOMALOUS LLVL EASTERLY FLOW DEVELOPS
THURSDAY INTO FRIDAY WITH THE CENTER OF HIGH PRESSURE SLIDING BY
ACROSS SRN ONTARIO.
LATEST LONG TERM GUIDANCE HAS FLOPPED BACK TO A DRIER SOLUTION
THAT WHAT WAS SHOWN YESTERDAY WITH REGARD CLOUDS/SHOWERS BEING
SLOW TO CLEAR OVER EASTERN PA. HOWEVER...SOLUTIONS ARE NOT
COMPLETELY DRY...THUS THIS APPEARS TO THE MAIN FORECAST PROBLEM
IN THE LONG TERM PERIOD.
UPPER RIDGING IS STILL FORECAST TO BUILD INTO THE MIDWEST/OHIO
VALLEY LATE IN THE WEEK /LED SEVERAL HUNDRED KM BY A 1024 MB SFC
HIGH/...LIKELY BRINGING ANOTHER SUMMER-LIKE PERIOD LATER IN THE
EXTENDED.
HOWEVER...WITH THE CENTER OF THE RIDGE SITUATED FROM THE MID MISS
VALLEY TO LAKE MICHIGAN...AND SLOW RETROGRADE OF THE NORTH ATLC
UPPER LOW...THERE IS STILL SOME UNCERTAINTY WITH RESPECT TO
TEMPS...THE DISTRIBUTION OF CLOUD COVER...THE CHANCE FOR DIURNAL
CONVECTION ACROSS THE EASTERN HALF OF PENN LATE IN THE WEEK AND
INTO THE UPCOMING WEEKEND.
&&
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
CLOUDS WILL CONTINUE TO THICKEN AND LOWER INTO THIS EVENING...IN
ADVANCE OF COLD FRONT APPROACHING FROM THE MIDWEST. AN UPPER
LEVEL DISTURBANCE LIFTING NWD ALONG THE APPALACHIANS AND COULD
TRIGGER ISOLD-SCT SHOWER OR TSTM OVER S/W PA THROUGH THIS EVE.
THE MAIN UPPER TROUGH SWINGS ACROSS THE GREAT LAKES LATER TONIGHT
INTO TUES...PUSHING THE COLD FRONT THROUGH CENTRAL PA. EXPECT SHRA
TO INCREASE IN CVRG/INTENSITY AND SPREAD EASTWARD OVERNIGHT INTO
TUES...BEFORE TAPERING OFF FROM WEST TO EAST TUES NGT. MOIST S-SE
LOW LEVEL FLOW WILL SUPPORT LOW MVFR TO IFR CIGS...WITH VIS
FLUCTUATIONS IN MOD TO OCNLY HVY SHRA/TSRA.
ONCE THE FRONT PULLS EAST OF THE REGION...THE REMAINDER OF THE
WEEK /WED-SAT/ LOOKS RELATIVELY QUIET AS HIGH PRESSURE BUILDS
INTO THE NE UNITED STATES.
OUTLOOK...
WED-FRI...GENERALLY VFR. ISOLD SHRA/TSRA POSSIBLE EACH AFTN.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...LAMBERT/GARTNER
AVIATION...EVANEGO
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
241 PM EDT MON JUN 11 2012
.SYNOPSIS...
A FRONTAL SYSTEM WILL APPROACH FROM THE WEST AND GENERATE
WIDESPREAD SHOWERS AND THUNDERSTORMS FOR LATE TONIGHT AND
TUESDAY. THE COLD FRONT WILL PASS THROUGH TUESDAY NIGHT. THIS
FRONT MAY STALL OUT NEAR THE MID ATLANTIC COAST FOR THE MIDDLE
AND LATTER PART OF THIS WEEK DELAYING THE EXIT OF CLOUDS AND
SHOWERS OUT OF THE EASTERN HALF OF PENNSYLVANIA.
&&
.NEAR TERM /THROUGH TONIGHT/...
MSTR ALOFT IS THICKENING UP AND DIURNAL CU IS FORMING/FILLING IN.
THE LOW CRUD IN THE EAST IS GONE. THICKER LINE OF CU FORMING FROM
YORK TO STATE COLLEGE COULD MAKE ISOLD SHRA BEFORE SUNSET. THE MESO
MDLS LIKE THE HRRR AND RUC DO GENERATE SOME RAINFALL THROUGH THE
CONVECTIVE PARAM. SHOWERS ALSO MOVING THRU FAR WRN PA HAVE A
DISTINCT LACK OF LTG DESPITE LOW STABILITY. EXPECT THESE SHOWERS
TO SLIDE TO THE WEST AND AFFECT THE FAR WRN ZONES THIS EVENING.
RAIN WILL NOT BE HEAVY AT ALL...WITH JUST A TENTH OR SO BEFORE
MIDNIGHT. WILL STILL MENTION SLIGHT CHC T FOR THE REGION WITH
STABILITY LOW. MOST OF THE PRECIP WILL WAIT UNTIL AFTER MIDNIGHT
WHEN THE HEIGHTS START TO DROP FASTER. PWATS CLIMB MORE THAN AN
INCH THRU SUNRISE AND THE MDL SOUNDINGS DECIDEDLY MOIST-ADIABATIC
FOR LATER TONIGHT...SO HEAVY RAIN FROM ANY CONVECTION IS POSSIBLE.
SKY COVER WILL BECOME 100PCT THIS EVENING AND EARLY TONIGHT.
THUS...TEMPS SHOULD NOT FALL FAR BELOW THE MID 60S.
FFG AND FFH NUMBERS ARE PRETTY LOFTY - ON THE ORDER OF 2.5 TO 3.5
INCHES IN 3 HRS...SO IT WOULD NEED TO BE MUCH HEAVIER RAIN THAN
EXPECTED TO CREATE FLOODING PROBLEMS. THE DURATION OF THE EVENT
AND PROGRESSIVE NATURE OF THE TROUGH AND FRONT ARGUE AGAINST ANY
FLOOD WATCHES.
&&
.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
CATEGORICAL POPS ARE STILL IN ORDER THROUGH ALL OF TUESDAY AND
INTO TUESDAY EVENING. STABLE PRECIP SHOULD DOMINATE OVER
CONVECTIVE FORCING. LLJET IS NOT STRONG AT ALL. SHEAR ALSO ONLY
WEAK TO MODERATE. HOWEVER...SPC DOES MENTION THE AREA IN THE DAY2
OUTLOOK. WILL KEEP THE MENTION OF THUNDER IN BUT FOREGO MENTIONS
OF GUSTY WINDS OR HAIL. I THINK IT WILL BE HARD TO GET THE CLOUDS
OUT OF THE WAY LONG ENOUGH AND MATCH UP THE TIMING OF UPPER
FORCING OR THE COLD FRONT WITH THAT POSSIBLE WINDOW OF STRONGER
SFC HEATING AND DESTABILIZATION.
THE HIGH PRECIP WATER WILL NOT BE TAPPED VERY EFFECTIVELY WITHOUT
WIDESPREAD UPRIGHT CONVECTION TO TAP INTO IT. OVERALL...A GENERAL
1 INCH OF PRECIP IS LOOKING LIKE THE STORM TOTAL. EXPECT SLIGHTLY
LOWER AMOUNTS TO THE WEST AND HIGHER AMOUNTS IN THE EAST.
AGAIN...THOSE AMOUNTS SHOULD NOT RAISE EYEBROWS WITH VEGETATION
FULLY GROWN AND STREAM FLOWS AROUND NORMAL.
TIMING OF THE FROPA LOOKS LIKE IT WILL BE A BIT QUICKER THAN PREV
FCSTS...WITH WINDS SHIFTING TO THE WEST LATE TUES AFTN IN THE WEST
AND IN THE EAST BY MIDNIGHT. THUS...WILL KEEP POPS HIGH FOR THE
DAYLIGHT HRS...BUT TAPER THEM OFF COMPLETELY FROM WEST TO EAST
BEFORE SUNRISE WED. THE FRONT ITSELF WILL HANG BACK BEHIND THE
MAIN SHIELD OF PRECIP AND GENERATE SOME LOW-TOPPED SHOWERS AS IT
MOVES THROUGH. MAXES WILL BE IN THE 70S OVERALL WITHOUT SIG BREAKS
IN THE SKY COVER. DRY AIR FINALLY WORKS IN TO THE WEST TUES NIGHT
AS THE STRONGEST SHORT WAVE PUSHES THROUGH. CLEARING - IN THE WEST
AT LEAST - MAY ALLOW FOG TO FORM AS TEMPS DIP CLOSE TO 50 IN THE
WRN MTS AND MID 50S TO NEAR 60 IN THE CENTRAL AND EAST. BUT WIND
AND DRYING AIRMASS MAY NEGATE THAT AS WELL.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
THE CFRONTAL BOUNDARY WILL HAVE PUSHED THE DEEP MOISTURE EAST OF THE
AREA TO BEGIN THE PERIOD. HOWEVER...AN UPPER LOW FCST TO CUT-OFF OVER
THE NORTH ATLANTIC /FOLLOWED BY A DEVELOPING REX BLOCK/ MAY HOLD THE
BOUNDARY/TROFFINESS ALONG THE MID ATLANTIC SEABOARD FOR SEVERAL DAYS
MORE. THIS WILL KEEP AT LEAST A LOW POTENTIAL FOR SOME SHOWERS AND
COOLER TEMPERATURES ACROSS THE EASTERN PARTS OF CENTRAL PA...AS A
SLIGHTLY ANOMALOUS LLVL EASTERLY FLOW DEVELOPS THURSDAY INTO FRIDAY
WITH THE CENTER OF HIGH PRESSURE SLIDING BY ACROSS SRN ONTARIO.
UPPER RIDGING IS STILL FORECAST TO BUILD INTO THE MIDWEST/OHIO
VALLEY LATE IN THE WEEK /LED SEVERAL HUNDRED KM BY A 1024 MB SFC
HIGH/...LIKELY BRINGING ANOTHER SUMMER-LIKE PERIOD LATER IN THE
EXTENDED.
HOWEVER...WITH THE CENTER OF THE RIDGE SITUATED FROM THE MID MISS
VALLEY TO LAKE MICHIGAN...AND SLOW RETROGRADE OF THE NORTH ATLC
UPPER LOW...THERE IS STILL SOME UNCERTAINTY WITH RESPECT TO
TEMPS...THE DISTRIBUTION OF CLOUD COVER...THE THE CHC FOR DIURNAL
CONVECTION ACROSS THE EASTERN HALF OF PENN LATE IN THE WEEK AND INTO
THE UPCOMING WEEKEND.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
CLOUDS WILL CONTINUE TO THICKEN AND LOWER INTO THIS EVENING...IN
ADVANCE OF COLD FRONT APPROACHING FROM THE MIDWEST. AN UPPER
LEVEL DISTURBANCE LIFTING NWD ALONG THE APPALACHIANS AND COULD
TRIGGER ISOLD-SCT SHOWER OR TSTM OVER S/W PA THROUGH THIS EVE.
THE MAIN UPPER TROUGH SWINGS ACROSS THE GREAT LAKES LATER TONIGHT
INTO TUES...PUSHING THE COLD FRONT THROUGH CENTRAL PA. EXPECT SHRA
TO INCREASE IN CVRG/INTENSITY AND SPREAD EASTWARD OVERNIGHT INTO
TUES...BEFORE TAPERING OFF FROM WEST TO EAST TUES NGT. MOIST S-SE
LOW LEVEL FLOW WILL SUPPORT LOW MVFR TO IFR CIGS...WITH VIS
FLUCTUATIONS IN MOD TO OCNLY HVY SHRA/TSRA.
ONCE THE FRONT PULLS EAST OF THE REGION...THE REMAINDER OF THE
WEEK /WED-SAT/ LOOKS RELATIVELY QUIET AS HIGH PRESSURE BUILDS
INTO THE NE UNITED STATES.
OUTLOOK...
WED-FRI...GENERALLY VFR. ISOLD SHRA/TSRA POSSIBLE EACH AFTN.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...LAMBERT/GARTNER
AVIATION...EVANEGO
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1255 PM CDT MON JUN 11 2012
.DISCUSSION...
UPDATED FOR 18Z AVIATION DISCUSSION
&&
.PREV DISCUSSION... /ISSUED 1115 AM CDT MON JUN 11 2012/
UPDATE...
UPDATED FOR ANTICIPATED CONVECTION AND SEVERE THREAT.
DISCUSSION...
A FORWARD PROPAGATING MCS CONTINUES TO PROGRESS EAST-SOUTHEASTWARD
ACROSS SOUTHERN MISSOURI. THIS MCS IS PROGRESSING ALONG THE
NORTHEASTERN PERIPHERY OF STRONG ELEVATED MIXED LAYER (EML/CAP)
OVER MUCH OF ARKANSAS. THIS CAPPING INVERSION WAS ALSO EVIDENT
FROM THE 12Z KLZK SOUNDING. THE CAP WEAKENS WITH EASTWARD EXTENT
AND THE LATEST STEERING FLOW SUGGESTS THAT THE MCS SHOULD MAKE A
TURN MORE TOWARDS THE SOUTH AND INTO THE HEART OF THE MID SOUTH.
THE ATMOSPHERE WILL BECOME STRONGLY UNSTABLE IN THE PRE-CONVECTIVE
AIRMASS AHEAD OF THE MCS. MLCAPES SHOULD APPROACH OR EVEN EXCEED
4000 J/KG AS TEMPERATURES RISE TO NEAR 90 DEGREES WITH DEWPOINTS
REMAINING IN THE LOWER TO MIDDLE 70S. IN ADDITION...STEEPENING MID
LEVEL LAPSE RATES ON EDGE OF THE EML AROUND 7.0 C/KM AND LI/S
BETWEEN -8C AND -12C SHOULD BE MORE THAN ENOUGH TO SUSTAIN
CONVECTION AND ALLOW FOR THE POTENTIAL OF DAMAGING WINDS AND LARGE
HAIL. CONVECTION SHOULD REMAIN ORGANIZED ALONG THE ADVANCING COLD
POOL. ADDITIONAL CONVECTION MAY DEVELOP IN ADVANCE OF THE MCS AND
WITH STRONG INSTABILITY AND WEAK CAPPING MAY ALSO POSE A SEVERE
THREAT. PLAN TO EXPAND THE SLIGHT RISK AREAWIDE AND ADD MENTION OF
SEVERE IN THE ZONES. ALSO POPS HAVE BEEN ADJUSTED TO REFLECT THE
ANTICIPATED SITUATION.
UPDATED ZONES AND GRIDS HAVE BEEN SENT AND THE HWO WILL BE UPDATED
SHORTLY.
JLH
DISCUSSION... /ISSUED 449 AM CDT MON JUN 11 2012/
PRIMARY SHORT TERM FORECAST CONCERN REMAINS RAIN CHANCES. EARLY
THIS MORNING... SHORTWAVE RIDGING WAS SPREADING INTO THE
MIDSOUTH... IN THE WAKE OF AN UPPER LEVEL SHEAR AXIS THAT BROUGHT
SCATTERED SHOWERS TO THE REGION ON SUNDAY. UPSTREAM OF THE
SHORTWAVE RIDGE AXIS... A ROBUST LINEAR MCS WAS DROPPING SOUTHEAST
THROUGH NW MISSOURI. 850/500MB THICKNESS ANALYSIS SUGGESTS THIS
FEATURE MAY BEGIN A MORE SOUTHERLY PROPAGATION. KSGF VAD WIND
PROFILER SHOWED 25KTS OF INFLOW...THOUGH THIS INFLOW SHOULD WEAKEN
CONSIDERABLY FOLLOWING SUNRISE.
AFTER A WEAKENING OF THE MO STORM COMPLEX... NAM MODEL REDEVELOPS
STORMS OVER THE OZARK PLATEAU TOWARD MIDDAY. THIS APPEARS A
REASONABLE SCENARIO...IN RESPONSE TO SURFACE HEATING... FALLING
HEIGHTS AND INCREASING UPPER LEVEL DIFFLUENCE AHEAD OF A LONG WAVE
TROF.
SURFACED BASED INSTABILITY SHOULD BE IN GOOD SUPPLY ACROSS THE
MIDSOUTH THIS AFTERNOON... WITH PARTIAL SUN AND LOWER 70S DEWPOINTS.
DESPITE WEAK SHORTWAVE RIDGING...THE HIGH DEWPOINTS SHOULD MAKE
CONVECTIVE TEMPS ATTAINABLE THIS AFTERNOON...ENOUGH TO WARRANT
CHANCE POPS.
MORE ORGANIZED CONVECTIVE ACTIVITY WILL BE POSSIBLE LATE THIS
AFTERNOON AND EVENING. THE RIGHT ENTRANCE REGION OF AN UPPER JET
CORE WILL INCREASE UPPER LEVEL DIFFLUENCE OVER THE MIDSOUTH... A
PATTERN WHICH WILL WILL REMAIN RELATIVELY STATIC OVERNIGHT. THIS
SUGGESTS ELEVATED STORMS MAY CONTINUE INTO THE OVERNIGHT...
THROUGH MESOSCALE PROPAGATION PROCESSES WILL PLAY A LARGE ROLE ON
WHERE STORMS OCCUR.
A SURFACE COLD FRONT ARRIVES TUESDAY MORNING...BRINGING DRIER
MIDCONTINENTAL AIR TO AREAS NORTH OF I40 BY AFTERNOON. 06Z NAM
SUGGESTS THE FRONT MAY HANG UP OVER NORTH MS TUESDAY AFTERNOON...
PROVIDING FOCUS FOR ADDITIONAL THUNDERSTORMS.
WEDNESDAY WILL SEE DRIER AIR OVER ALL THE MIDSOUTH. TEMPERATURES
WILL RECOVER TO NEAR OR SLIGHTLY ABOVE NORMAL VALUES FOR THE
LATTER HALF OF THE WEEK. BY FRIDAY... DEWPOINTS RECOVER TO THE
60S. DRY CONDITIONS WILL PREVAIL...THOUGH CANNOT RULE OUT AN
ISOLATED AFTERNOON THUNDERSTORM OR TWO UNDER AN UPPER LEVEL
SYNOPTIC SCALE RIDGE.
PWB
&&
.AVIATION...
18Z TAF SET
CONVECTIVE COMPLEX IS SET TO SWEEP THROUGH THE MIDSOUTH THIS
AFTERNOON AND EARLY THIS EVENING. THIS IS CORROBORATED WELL BY THE
LATEST HRRR RUN. HAVE TIMED TEMPO GROUPS AT ALL SITES. EXPECT A
FEW QUIET HOURS AFTER THE PASSAGE OF THE FIRST ROUND OF TSRAS.
EXPECT REDEVELOPMENT TO OCCUR OVERNIGHT AS THE FRONT MOVES INTO
THE REGION. KEPT A VCTS GOING FOR NOW SINCE IT IS DIFFICULT TO
TIME THIS MESOSCALE ACTIVITY BEYOND A FEW HOURS. EXPECT SSW WINDS
AT 8-10 KTS THIS AFTERNOON. AS THE COMPLEX MOVES THROUGH WINDS
SHOULD SHARPLY SHIFT TO THE NORTH AND GUST. ADDED A WIND GROUP TO
KJBR IN ANTICIPATION OF THIS. NOT CONFIDENT ENOUGH AT THE OTHER
3 SITES TO ADD THIS YET. EXPECT WINDS TO BACK AFTER THE COMPLEX
MOVES THROUGH AND THEN EVENTUALLY RETURN TO LIGHT SOUTHERLY
OVERNIGHT. THE FRONT WILL PASS THROUGH EARLY TUESDAY AND WINDS
WILL SHIFT TO THE NORTH AT 8-10 KTS.
SJM
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 90 74 87 65 / 60 50 40 10
MKL 88 69 85 59 / 60 50 40 0
JBR 87 67 86 61 / 80 50 10 0
TUP 89 71 86 65 / 50 60 60 10
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1115 AM CDT MON JUN 11 2012
.UPDATE...
UPDATED FOR ANTICIPATED CONVECTION AND SEVERE THREAT.
&&
.DISCUSSION...
A FORWARD PROPAGATING MCS CONTINUES TO PROGRESS EAST-SOUTHEASTWARD
ACROSS SOUTHERN MISSOURI. THIS MCS IS PROGRESSING ALONG THE
NORTHEASTERN PERIPHERY OF STRONG ELEVATED MIXED LAYER (EML/CAP)
OVER MUCH OF ARKANSAS. THIS CAPPING INVERSION WAS ALSO EVIDENT
FROM THE 12Z KLZK SOUNDING. THE CAP WEAKENS WITH EASTWARD EXTENT
AND THE LATEST STEERING FLOW SUGGESTS THAT THE MCS SHOULD MAKE A
TURN MORE TOWARDS THE SOUTH AND INTO THE HEART OF THE MID SOUTH.
THE ATMOSPERE WILL BECOME STRONGLY UNSTABLE IN THE PRE-CONVECTIVE
AIRMASS AHEAD OF THE MCS. MLCAPES SHOULD APPROACH OR EVEN EXCEED
4000 J/KG AS TEMPERATURES RISE TO NEAR 90 DEGREES WITH DEWPOINTS
REMAINING IN THE LOWER TO MIDDLE 70S. IN ADDITION...STEEPENING MID
LEVEL LAPSE RATES ON EDGE OF THE EML AROUND 7.0 C/KM AND LI/S
BETWEEN -8C AND -12C SHOULD BE MORE THAN ENOUGH TO SUSTAIN
CONVECTION AND ALLOW FOR THE POTENTIAL OF DAMAGING WINDS AND LARGE
HAIL. CONVECTION SHOULD REMAIN ORGANIZED ALONG THE ADVANCING COLD
POOL. ADDITIONAL CONVECTION MAY DEVELOP IN ADVANCE OF THE MCS AND
WITH STRONG INSTABILITY AND WEAK CAPPING MAY ALSO POSE A SEVERE
THREAT. PLAN TO EXPAND THE SLIGHT RISK AREAWIDE AND ADD MENTION OF
SEVERE IN THE ZONES. ALSO POPS HAVE BEEN ADJUSTED TO REFLECT THE
ANTICIPATED SITUATION.
UPDATED ZONES AND GRIDS HAVE BEEN SENT AND THE HWO WILL BE UPDATED
SHORTLY.
JLH
&&
.PREV DISCUSSION... /ISSUED 559 AM CDT MON JUN 11 2012/
DISCUSSION... /ISSUED 449 AM CDT MON JUN 11 2012/
PRIMARY SHORT TERM FORECAST CONCERN REMAINS RAIN CHANCES. EARLY
THIS MORNING... SHORTWAVE RIDGING WAS SPREADING INTO THE
MIDSOUTH... IN THE WAKE OF AN UPPER LEVEL SHEAR AXIS THAT BROUGHT
SCATTERED SHOWERS TO THE REGION ON SUNDAY. UPSTREAM OF THE
SHORTWAVE RIDGE AXIS... A ROBUST LINEAR MCS WAS DROPPING SOUTHEAST
THROUGH NW MISSOURI. 850/500MB THICKNESS ANALYSIS SUGGESTS THIS
FEATURE MAY BEGIN A MORE SOUTHERLY PROPAGATION. KSGF VAD WIND
PROFILER SHOWED 25KTS OF INFLOW...THOUGH THIS INFLOW SHOULD WEAKEN
CONSIDERABLY FOLLOWING SUNRISE.
AFTER A WEAKENING OF THE MO STORM COMPLEX... NAM MODEL REDEVELOPS
STORMS OVER THE OZARK PLATEAU TOWARD MIDDAY. THIS APPEARS A
REASONABLE SCENARIO...IN RESPONSE TO SURFACE HEATING... FALLING
HEIGHTS AND INCREASING UPPER LEVEL DIFFLUENCE AHEAD OF A LONG WAVE
TROF.
SURFACED BASED INSTABILITY SHOULD BE IN GOOD SUPPLY ACROSS THE
MIDSOUTH THIS AFTERNOON... WITH PARTIAL SUN AND LOWER 70S DEWPOINTS.
DESPITE WEAK SHORTWAVE RIDGING...THE HIGH DEWPOINTS SHOULD MAKE
CONVECTIVE TEMPS ATTAINABLE THIS AFTERNOON...ENOUGH TO WARRANT
CHANCE POPS.
MORE ORGANIZED CONVECTIVE ACTIVITY WILL BE POSSIBLE LATE THIS
AFTERNOON AND EVENING. THE RIGHT ENTRANCE REGION OF AN UPPER JET
CORE WILL INCREASE UPPER LEVEL DIFFLUENCE OVER THE MIDSOUTH... A
PATTERN WHICH WILL WILL REMAIN RELATIVELY STATIC OVERNIGHT. THIS
SUGGESTS ELEVATED STORMS MAY CONTINUE INTO THE OVERNIGHT...
THROUGH MESOSCALE PROPAGATION PROCESSES WILL PLAY A LARGE ROLE ON
WHERE STORMS OCCUR.
A SURFACE COLD FRONT ARRIVES TUESDAY MORNING...BRINGING DRIER
MIDCONTINENTAL AIR TO AREAS NORTH OF I40 BY AFTERNOON. 06Z NAM
SUGGESTS THE FRONT MAY HANG UP OVER NORTH MS TUESDAY AFTERNOON...
PROVIDING FOCUS FOR ADDITIONAL THUNDERSTORMS.
WEDNESDAY WILL SEE DRIER AIR OVER ALL THE MIDSOUTH. TEMPERATURES
WILL RECOVER TO NEAR OR SLIGHTLY ABOVE NORMAL VALUES FOR THE
LATTER HALF OF THE WEEK. BY FRIDAY... DEWPOINTS RECOVER TO THE
60S. DRY CONDITIONS WILL PREVAIL...THOUGH CANNOT RULE OUT AN
ISOLATED AFTERNOON THUNDERSTORM OR TWO UNDER AN UPPER LEVEL
SYNOPTIC SCALE RIDGE.
PWB
&&
.AVIATION...
12Z TAF SET
COLD FRONT EXPECTED TO MOVE INTO THE CWA OVERNIGHT. HRRR MODEL HAS
INITIALIZED THE BEST WITH ONGOING ACTIVITY UP ACROSS MISSOURI THUS
HAVE LEANED TOWARD THIS SOLUTION WITH NEW TAF SET. EXPECT POSSIBLY
TWO ROUNDS OF SHRA/TSRA ACTIVITY. FIRST...MODEL INDICATING A TSRA
COMPLEX DEVELOPING OVER NW ARKANSAS/SW MISSOURI AROUND 17-18Z. MCS
WILL PUSH EAST INTO KJBR AFTER 20Z AND POSSIBLY INTO KMEM AFTER
21Z. HAVE ADDED TEMPO GROUPS TO NEW TAF AS A RESULT. NAM ALSO
SHOWS THIS FIRST ROUND OF ACTIVITY OCCURRING. THEREAFTER...CONFIDENCE
WANES AS HOW FAR EAST AND SOUTH COMPLEX WILL PUSH. A SECOND ROUND OF
ACTIVITY COULD OCCUR ALONG FRONT AS IT PUSHES INTO THE AREA. FOR
NOW JUST LEFT VCTS WORDING AS CONFIDENCE IS LOW AS EARLIER TSRA
COMPLEX (IF IT DOES DEVELOP) COULD STABILIZE THE ATMOSPHERE KILLING
ANY ACTIVITY PUSHING INTO THE AREA ALONG THE FRONT. IF HAD TO PICK
BEST TIMING AT KMEM FOR SECOND ROUND ACTIVITY TO OCCUR WOULD PICK
SOMEWHERE BETWEEN 6Z- 10Z. OTHERWISE...IFR CIGS CURRENTLY OCCURRING
SHOULD LIFT TO VFR BY 15-19Z DEPENDING ON LOCATION. SW WINDS
BETWEEN 8-12 KTS EXPECTED TODAY...SPEEDS WILL DECREASE AFTER 01Z.
KRM
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 90 74 87 65 / 60 50 40 10
MKL 88 69 85 59 / 60 50 40 0
JBR 87 67 86 61 / 80 50 10 0
TUP 89 71 86 65 / 50 60 60 10
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
559 AM CDT MON JUN 11 2012
.DISCUSSION... /ISSUED 449 AM CDT MON JUN 11 2012/
PRIMARY SHORT TERM FORECAST CONCERN REMAINS RAIN CHANCES. EARLY
THIS MORNING... SHORTWAVE RIDGING WAS SPREADING INTO THE
MIDSOUTH... IN THE WAKE OF AN UPPER LEVEL SHEAR AXIS THAT BROUGHT
SCATTERED SHOWERS TO THE REGION ON SUNDAY. UPSTREAM OF THE
SHORTWAVE RIDGE AXIS... A ROBUST LINEAR MCS WAS DROPPING SOUTHEAST
THROUGH NW MISSOURI. 850/500MB THICKNESS ANALYSIS SUGGESTS THIS
FEATURE MAY BEGIN A MORE SOUTHERLY PROPAGATION. KSGF VAD WIND
PROFILER SHOWED 25KTS OF INFLOW...THOUGH THIS INFLOW SHOULD WEAKEN
CONSIDERABLY FOLLOWING SUNRISE.
AFTER A WEAKENING OF THE MO STORM COMPLEX... NAM MODEL REDEVELOPS
STORMS OVER THE OZARK PLATEAU TOWARD MIDDAY. THIS APPEARS A
REASONABLE SCENARIO...IN RESPONSE TO SURFACE HEATING... FALLING
HEIGHTS AND INCREASING UPPER LEVEL DIFFLUENCE AHEAD OF A LONG WAVE
TROF.
SURFACED BASED INSTABILITY SHOULD BE IN GOOD SUPPLY ACROSS THE
MIDSOUTH THIS AFTERNOON... WITH PARTIAL SUN AND LOWER 70S DEWPOINTS.
DESPITE WEAK SHORTWAVE RIDGING...THE HIGH DEWPOINTS SHOULD MAKE
CONVECTIVE TEMPS ATTAINABLE THIS AFTERNOON...ENOUGH TO WARRANT
CHANCE POPS.
MORE ORGANIZED CONVECTIVE ACTIVITY WILL BE POSSIBLE LATE THIS
AFTERNOON AND EVENING. THE RIGHT ENTRANCE REGION OF AN UPPER JET
CORE WILL INCREASE UPPER LEVEL DIFFLUENCE OVER THE MIDSOUTH... A
PATTERN WHICH WILL WILL REMAIN RELATIVELY STATIC OVERNIGHT. THIS
SUGGESTS ELEVATED STORMS MAY CONTINUE INTO THE OVERNIGHT...
THROUGH MESOSCALE PROPAGATION PROCESSES WILL PLAY A LARGE ROLE ON
WHERE STORMS OCCUR.
A SURFACE COLD FRONT ARRIVES TUESDAY MORNING...BRINGING DRIER
MIDCONTINENTAL AIR TO AREAS NORTH OF I40 BY AFTERNOON. 06Z NAM
SUGGESTS THE FRONT MAY HANG UP OVER NORTH MS TUESDAY AFTERNOON...
PROVIDING FOCUS FOR ADDITIONAL THUNDERSTORMS.
WEDNESDAY WILL SEE DRIER AIR OVER ALL THE MIDSOUTH. TEMPERATURES
WILL RECOVER TO NEAR OR SLIGHTLY ABOVE NORMAL VALUES FOR THE
LATTER HALF OF THE WEEK. BY FRIDAY... DEWPOINTS RECOVER TO THE
60S. DRY CONDITIONS WILL PREVAIL...THOUGH CANNOT RULE OUT AN
ISOLATED AFTERNOON THUNDERSTORM OR TWO UNDER AN UPPER LEVEL
SYNOPTIC SCALE RIDGE.
PWB
&&
.AVIATION...
12Z TAF SET
COLD FRONT EXPECTED TO MOVE INTO THE CWA OVERNIGHT. HRRR MODEL HAS
INITIALIZED THE BEST WITH ONGOING ACTIVITY UP ACROSS MISSOURI THUS
HAVE LEANED TOWARD THIS SOLUTION WITH NEW TAF SET. EXPECT POSSIBLY
TWO ROUNDS OF SHRA/TSRA ACTIVITY. FIRST...MODEL INDICATING A TSRA
COMPLEX DEVELOPING OVER NW ARKANSAS/SW MISSOURI AROUND 17-18Z. MCS
WILL PUSH EAST INTO KJBR AFTER 20Z AND POSSIBLY INTO KMEM AFTER
21Z. HAVE ADDED TEMPO GROUPS TO NEW TAF AS A RESULT. NAM ALSO
SHOWS THIS FIRST ROUND OF ACTIVITY OCCURRING. THEREAFTER...CONFIDENCE
WANES AS HOW FAR EAST AND SOUTH COMPLEX WILL PUSH. A SECOND ROUND OF
ACTIVITY COULD OCCUR ALONG FRONT AS IT PUSHES INTO THE AREA. FOR
NOW JUST LEFT VCTS WORDING AS CONFIDENCE IS LOW AS EARLIER TSRA
COMPLEX (IF IT DOES DEVELOP) COULD STABILIZE THE ATMOSPHERE KILLING
ANY ACTIVITY PUSHING INTO THE AREA ALONG THE FRONT. IF HAD TO PICK
BEST TIMING AT KMEM FOR SECOND ROUND ACTIVITY TO OCCUR WOULD PICK
SOMEWHERE BETWEEN 6Z- 10Z. OTHERWISE...IFR CIGS CURRENTLY OCCURRING
SHOULD LIFT TO VFR BY 15-19Z DEPENDING ON LOCATION. SW WINDS
BETWEEN 8-12 KTS EXPECTED TODAY...SPEEDS WILL DECREASE AFTER 01Z.
KRM
&&
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 90 74 87 65 / 40 50 40 10
MKL 87 69 85 59 / 40 50 40 0
JBR 88 67 86 61 / 40 50 10 0
TUP 88 71 86 65 / 40 60 60 10
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1254 AM CDT MON JUN 11 2012
.UPDATE... /ISSUED 846 PM CDT SUN JUN 10 2012/
LATEST IR SAT AND RUC13 DATA SHOWS THE UPPER LEVEL LOW MOVING
SLOWLY NE TOWARDS MIDDLE TN THIS EVENING FROM NEAR COLUMBUS MS.
WITH THE LOSS OF HEATING SHOWERS AND THUNDERSTORMS ARE STARTING TO
DECLINE IN COVERAGE ACROSS THE REGION. HAVE LOWERED POPS THROUGH
06Z WITH JUST ISOLATED TO SCTD SHWRS AND TSTORMS IN THE EASTERN
PORTIONS OF THE FORECAST AREA OVERNIGHT INTO THE MORNING AT BEST.
HIGH CONFIDENCE THAT ONLY A FEW SPOTS WILL EVEN SEE THIS ACTIVITY.
TWEAKED TEMPS AND DEWPTS TO MATCH CURRENT READINGS WITH FORECAST
LOWS LOOKING GOOD AT THIS POINT. --ABS
&&
.PREV DISCUSSION... /ISSUED 251 PM CDT SUN JUN 10 2012/
INSTABILITY IS IN PLACE...HOWEVER WEAK LOW LEVEL CONVERGENCE HAS
BEEN HINDERING CONVECTION...AND A FEW SHOWERS THAT HAVE DEVELOPED
HAVE BEEN LIGHT...WITH THE EXCEPTION OF NORTHEAST MISSISSIPPI. NOT
CONFIDENT WITH THE 12Z MODELS THAT A QUARTER TO A HALF INCH IN QPF
AMOUNTS WILL OVERSPREAD THE MIDSOUTH THROUGH 11/00Z. THEY MAY
RECEIVE THAT AMOUNT ACROSS PORTIONS OF NORTHEAST MISSISSIPPI BUT
THAT`S ALL. THIS AREA WILL ALSO BE FAVORED FOR AN OCCASIONAL CLAP
OF THUNDER...BUT STRONG STORMS SEEMS UNLIKELY. MOST MIDSOUTHERNERS
HOWEVER WILL BE LUCKY TO SEE A FEW HUNDREDTHS OF AN INCH. BY
SUNSET ANY LINGERING SHOWERS SHOULD BEGIN TO QUICKLY
DISSIPATE...WITH DRY CONDITIONS EXPECTED FOR MOST OF THE AREA.
ONLY THE FAR EASTERN COUNTIES MAY CONTINUE TO SEE SCATTERED SHOWER
ACTIVITY. MOSTLY CLOUDY TO CLOUDY SKIES WILL BE THE RULE AREA
WIDE...KEEPING LOW TEMPERATURES A DEGREE OR TWO WARMER THEN LAST
NIGHT.
MONDAY AND TUESDAY...THE LOW PRESSURE DISTURBANCE CURRENTLY OVER
THE MIDSOUTH WILL SLOWLY TRACK EAST THROUGH THE VOLUNTEER STATE AS
A MAJOR SHORTWAVE IN THE MAIN JET FLOW CROSSES THE NORTHERN PLAINS
AND UPPER MIDWEST. THIS ENERGY WILL SEND A COLD FRONT SOUTHEAST
THROUGH THE MID MISSISSIPPI VALLEY MONDAY AFTERNOON. PORTIONS OF
THE MIDSOUTH WEST OF THE RIVER ARE ZONED FOR A SLIGHT RISK OF
SEVERE WEATHER MONDAY EVENING AND OVERNIGHT AS THE TAIL END OF
THE FRONT CROSSES THE OZARKS. LIFTED INDICES NEAR -10C ARE
PROGGED FOR LATE TOMORROW AND NEARLY THAT ACROSS NORTH MISSISSIPPI
BY MIDDAY TUESDAY AS THE FRONT PUSHES SOUTH. WILL LIKELY REMOVE
ANY WORDING FOR A STRONG STORM FOR THIS AFTERNOON WITH THE
DISTURBANCE...BUT KEEP MENTION OF SEVERE IN TOMORROW AND TUESDAY.
FORECAST HIGHS A BIT TRICKY FOR MONDAY AS LOW LEVEL CLOUD COVER
MAY BE ABUNDANT IN THE MORNING HOURS. HAVE LEANED TOWARD THE EURO
AND NAM WITH SLIGHTLY COOLER HIGHS. SAME SITUATION ON TUESDAY AS
CONVECTION WILL BE ONGOING OVER PORTIONS OF THE AREA.
WEDNESDAY THROUGH THURSDAY...MODELS SHOW THE REGION ON THE
SOUTH SIDE OF SURFACE HIGH PRESSURE WITH DRIER DEWPOINTS USHERING
IN ON NORTHEAST BREEZES. TEMPERATURES WILL BE NEAR AVERAGE FOR MID
JUNE...WITH ONLY A SLIGHT CHANCE OF AFTERNOON CONVECTION OVER THE
EXTREME SOUTHERN COUNTIES...WHERE DEWPOINTS IN THE MID 60S WILL
STILL BE FOUND.
NEXT WEEKEND...SOUTHERLY WINDS WILL BRING HIGHER HUMIDITY BACK TO
THE MIDSOUTH WITH ISOLATED SUMMERTIME AFTERNOON CONVECTION. HIGH
TEMPERATURES WILL WARM SLIGHTLY.
JAB
&&
.AVIATION...
06Z TAF CYCLE
OVERNIGHT...STILL THINK IFR CONDITIONS WILL DEVELOP AT KMKL AND KTUP
WITH LOWERING CEILINGS AND FOG...MVFR CEILINGS DEVELOPING AT KMEM
AND KJBR. CONDITIONS THEN GRADUALLY IMPROVING AFTER MID-MORNING
MONDAY BECOMING MOSTLY VFR AFTER 18Z. UPPER LEVEL RIDGING IS
EXPECTED TO TEMPORARILY SPREADING INTO THE AREA AS THE UPPER LEVEL
TROUGH THAT HAS BEEN MOVING THROUGH THE LOWER MS RIVER VALLEY THE
LAST COUPLE OF DAYS MOVES TO THE EAST. THIS MAY SUPPRESS CONVECTION
EARLY IN THE AFTERNOON...HOWEVER WITH LESS CLOUDS AND STRONG DAYTIME
HEATING EXPECTED DECIDED TO ADD VCTS TO THE TAFS AFTER 20Z-21Z.
CONTINUED THE MENTION OF VCTS AT KMEM...KMKL..AND KJBR MONDAY
EVENING THROUGH 12/06Z AS A COLD FRONT APPROACHES FROM THE
NORTHWEST. AT KTUP KEPT VCTS IN UNTIL 12/02Z THEN REMOVED IT WITH
THE LOSS OF DAYTIME HEATING.
SE-S WINDS 3-7 KTS TONIGHT BECOMING SW 8-12 KTS MONDAY...THEN AFTER
12/00Z GENERALLY SW 5 KTS.
JCL/KRM
&&
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 73 87 66 86 / 50 40 10 10
MKL 69 86 61 85 / 50 40 10 0
JBR 69 86 62 86 / 50 20 10 0
TUP 72 87 64 88 / 50 50 20 10
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
549 PM CDT MON JUN 11 2012
.SHORT TERM...THROUGH WEDNESDAY NIGHT
253 PM CDT MON JUN 11 2012
MAIN FORECAST CONCERN IS WITH THE TEMPERATURES THROUGH TUESDAY AND
RAIN CHANCES FOR WEDNESDAY NIGHT.
SURFACE ANALYSIS THIS AFTERNOON SHOWS A WIND SHIFT/DRY LINE
EXTENDING FROM NORTH CENTRAL WISCONSIN THROUGH THE FORECAST AREA
INTO NORTHWEST MISSOURI. LOCAL RADAR SHOWS A FEW SHOWERS
DEVELOPING ALONG THIS BOUNDARY.
THE HRRR HAS BEEN CONSISTENTLY SHOWING THE SHOWERS FORMING OVER
THE AREA THIS AFTERNOON. THE 11.15Z RUN CONTINUES THIS TREND
SHOWING THEM MOVING TO THE EAST THROUGH THE REMAINDER OF THE
AFTERNOON WITH THE BOUNDARY. THE SHOWERS AND BOUNDARY ARE EXPECTED
TO BE EAST OF THE FORECAST AREA BY 00Z...SO NO PLANS TO CARRY ANY
EVENING RAIN CHANCES.
AFTER THAT...IT IS A QUESTION OF HOW MUCH COOL AIR SETTLES IN OVER
THE AREA AS HIGH PRESSURE BUILDS IN. BOTH THE 11.12Z NAM AND GFS
INDICATE 925 MB TEMPERATURES SHOULD DIP DOWN TO 5-7C TONIGHT
BEFORE STARTING TO REBOUND TO AROUND 10C TUESDAY NIGHT. SURFACE
TEMPERATURES WILL GENERALLY FALL TO AROUND 50 TONIGHT AS A
NORTHWEST BREEZE IS EXPECTED TO CREATE JUST ENOUGH MIXING TO KEEP
THEM FROM GOING ANY LOWER. HIGHS TUESDAY WILL BE MUCH COOLER
TOPPING OUT IN THE UPPER 60S TO LOWER 70S. THE COOLEST NIGHT WILL
BE TUESDAY NIGHT DESPITE THE SLIGHTLY WARMER 925 MB TEMPERATURES.
THE SURFACE HIGH WILL BE RIGHT OVER THE AREA ALLOWING THE WINDS TO
DECOUPLE AND EXCELLENT RADIATIONAL COOLING TO OCCUR. EXPECTING
LOWS TO BE IN THE 40S WITH THE FAVORED COOLER SPOTS DIPPING INTO
THE UPPER 30S.
AS THE SURFACE HIGH THEN MOVES OFF TO THE EAST...THE CONCERN
BECOMES WHETHER THERE WILL BE ANY SHOWERS THAT DEVELOP IN THE
RETURN FLOW. THE MODELS SUGGEST THERE WILL BE A SHORT WAVE TROUGH
MOVING ACROSS THE DAKOTAS WEDNESDAY NIGHT WITH THE BEST PV
ADVECTION IN THE 500-300MB LAYER STAYING NORTHWEST OF THE AREA.
THE BEST LOW LEVEL MOISTURE TRANSPORT WILL BE INTO THIS WAVE...BUT
THERE WILL ALSO BE A WEAKER BRANCH SPLITTING OFF TO THE NORTHEAST
AHEAD OF ANOTHER SHORT WAVE TROUGH. THIS PLACES THE WESTERN
SECTIONS OF THE FORECAST UNDER UNDER THE EASTERN CONVERGENT SIDE
OF THE MOISTURE TRANSPORT AXIS. THIS IS EXPECTED TO COINCIDE WITH
1-2 UBAR/S OF UP GLIDE ON THE 310K ISENTROPIC SURFACE AND WHILE
THE FORCING IS NOT THAT STRONG FELT THERE WAS ENOUGH TO JUSTIFY A
20 PERCENT RAIN CHANCES LATE TUESDAY NIGHT OVER THE NORTHWEST
SECTIONS OF THE AREA.
.LONG TERM...THURSDAY THROUGH MONDAY
253 PM CDT MON JUN 11 2012
CONSIDERABLE UNCERTAINTY IN THE EXTENDED PART OF THE FORECAST. THE
UPPER LEVEL RIDGE IS EXPECTED TO BUILD FROM THE SOUTHERN PLAINS
INTO SOUTHEAST CANADA. MODELS HAVE BEEN SHOWING RUN TO RUN
DIFFERENCES ON HOW FAR WEST THE RIDGE WILL EXTEND AND WHETHER THIS
WILL ALLOW ANY SHORT WAVE TROUGHS IN THE SOUTHWEST FLOW TO IMPACT
THE AREA. THE 11.12Z ECMWF HAS COME IN WITH AN EVEN FLATTER AND
FARTHER EAST RIDGE AXIS WHICH ALLOWS A SYSTEM TO MOVE ACROSS THE
UPPER MIDWEST FOR THE WEEKEND. THE GFS AND 11.12Z GEM ARE MORE
ROBUST WITH THE RIDGE AXIS WHICH DEFLECTS THIS SYSTEM OFF TO THE
NORTHWEST. MODELS ARE KNOWN TO STRUGGLE MIGHTILY WITH SOUTHWEST
FLOW SO HAVE OPTED TO LEAVE IN THE SMALL RAIN CHANCES AS
CONFIDENCE TO PULL THEM OUT IS JUST NOT THERE.
&&
.AVIATION...TONIGHT AND TUESDAY
549 PM CDT MON JUN 11 2012
VFR CONDITIONS WILL OCCUR THROUGH TOMORROW AS COOLER AIR MOVES
INTO THE REGION BEHIND A COLD FRONT. WINDS WILL BE THE TRICKIEST
PART OF THE FORECAST WITH SOME FORECAST GUIDANCE...THE 11.21Z RAP
MODEL...SHOWING THAT SOME LOW LEVEL MIXING WILL CONTINUE
OVERNIGHT AND KEEP SOME GUSTS AROUND. AS SURFACE TEMPERATURES DROP
THIS EVENING...THINK THAT WE SHOULD BE ABLE TO DECOUPLE AND END
THE GUSTS BETWEEN 1-2Z. THE PRESSURE GRADIENT WILL REMAIN TIGHT
OVERNIGHT...SO HAVE KEPT THE SUSTAINED WINDS UP BETWEEN 12-16KTS.
OTHERWISE...SKIES WILL CLEAR OUT WITH VFR FAIR WEATHER CU
REFORMING TOMORROW MORNING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
253 PM CDT MON JUN 11 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...HALBACH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
254 PM CDT MON JUN 11 2012
.SHORT TERM...THROUGH WEDNESDAY NIGHT
253 PM CDT MON JUN 11 2012
MAIN FORECAST CONCERN IS WITH THE TEMPERATURES THROUGH TUESDAY AND
RAIN CHANCES FOR WEDNESDAY NIGHT.
SURFACE ANALYSIS THIS AFTERNOON SHOWS A WIND SHIFT/DRY LINE
EXTENDING FROM NORTH CENTRAL WISCONSIN THROUGH THE FORECAST AREA
INTO NORTHWEST MISSOURI. LOCAL RADAR SHOWS A FEW SHOWERS
DEVELOPING ALONG THIS BOUNDARY.
THE HRRR HAS BEEN CONSISTENTLY SHOWING THE SHOWERS FORMING OVER
THE AREA THIS AFTERNOON. THE 11.15Z RUN CONTINUES THIS TREND
SHOWING THEM MOVING TO THE EAST THROUGH THE REMAINDER OF THE
AFTERNOON WITH THE BOUNDARY. THE SHOWERS AND BOUNDARY ARE EXPECTED
TO BE EAST OF THE FORECAST AREA BY 00Z...SO NO PLANS TO CARRY ANY
EVENING RAIN CHANCES.
AFTER THAT...IT IS A QUESTION OF HOW MUCH COOL AIR SETTLES IN OVER
THE AREA AS HIGH PRESSURE BUILDS IN. BOTH THE 11.12Z NAM AND GFS
INDICATE 925 MB TEMPERATURES SHOULD DIP DOWN TO 5-7C TONIGHT
BEFORE STARTING TO REBOUND TO AROUND 10C TUESDAY NIGHT. SURFACE
TEMPERATURES WILL GENERALLY FALL TO AROUND 50 TONIGHT AS A
NORTHWEST BREEZE IS EXPECTED TO CREATE JUST ENOUGH MIXING TO KEEP
THEM FROM GOING ANY LOWER. HIGHS TUESDAY WILL BE MUCH COOLER
TOPPING OUT IN THE UPPER 60S TO LOWER 70S. THE COOLEST NIGHT WILL
BE TUESDAY NIGHT DESPITE THE SLIGHTLY WARMER 925 MB TEMPERATURES.
THE SURFACE HIGH WILL BE RIGHT OVER THE AREA ALLOWING THE WINDS TO
DECOUPLE AND EXCELLENT RADIATIONAL COOLING TO OCCUR. EXPECTING
LOWS TO BE IN THE 40S WITH THE FAVORED COOLER SPOTS DIPPING INTO
THE UPPER 30S.
AS THE SURFACE HIGH THEN MOVES OFF TO THE EAST...THE CONCERN
BECOMES WHETHER THERE WILL BE ANY SHOWERS THAT DEVELOP IN THE
RETURN FLOW. THE MODELS SUGGEST THERE WILL BE A SHORT WAVE TROUGH
MOVING ACROSS THE DAKOTAS WEDNESDAY NIGHT WITH THE BEST PV
ADVECTION IN THE 500-300MB LAYER STAYING NORTHWEST OF THE AREA.
THE BEST LOW LEVEL MOISTURE TRANSPORT WILL BE INTO THIS WAVE...BUT
THERE WILL ALSO BE A WEAKER BRANCH SPLITTING OFF TO THE NORTHEAST
AHEAD OF ANOTHER SHORT WAVE TROUGH. THIS PLACES THE WESTERN
SECTIONS OF THE FORECAST UNDER UNDER THE EASTERN CONVERGENT SIDE
OF THE MOISTURE TRANSPORT AXIS. THIS IS EXPECTED TO COINCIDE WITH
1-2 UBAR/S OF UP GLIDE ON THE 310K ISENTROPIC SURFACE AND WHILE
THE FORCING IS NOT THAT STRONG FELT THERE WAS ENOUGH TO JUSTIFY A
20 PERCENT RAIN CHANCES LATE TUESDAY NIGHT OVER THE NORTHWEST
SECTIONS OF THE AREA.
.LONG TERM...THURSDAY THROUGH MONDAY
253 PM CDT MON JUN 11 2012
CONSIDERABLE UNCERTAINTY IN THE EXTENDED PART OF THE FORECAST. THE
UPPER LEVEL RIDGE IS EXPECTED TO BUILD FROM THE SOUTHERN PLAINS
INTO SOUTHEAST CANADA. MODELS HAVE BEEN SHOWING RUN TO RUN
DIFFERENCES ON HOW FAR WEST THE RIDGE WILL EXTEND AND WHETHER THIS
WILL ALLOW ANY SHORT WAVE TROUGHS IN THE SOUTHWEST FLOW TO IMPACT
THE AREA. THE 11.12Z ECMWF HAS COME IN WITH AN EVEN FLATTER AND
FARTHER EAST RIDGE AXIS WHICH ALLOWS A SYSTEM TO MOVE ACROSS THE
UPPER MIDWEST FOR THE WEEKEND. THE GFS AND 11.12Z GEM ARE MORE
ROBUST WITH THE RIDGE AXIS WHICH DEFLECTS THIS SYSTEM OFF TO THE
NORTHWEST. MODELS ARE KNOWN TO STRUGGLE MIGHTILY WITH SOUTHWEST
FLOW SO HAVE OPTED TO LEAVE IN THE SMALL RAIN CHANCES AS
CONFIDENCE TO PULL THEM OUT IS JUST NOT THERE.
&&
.AVIATION...THIS AFTERNOON THROUGH TUESDAY
1220 PM CDT MON JUN 11 2012
QUIET...GOOD VFR PERIOD FOR THIS AFTERNOON THRU TUESDAY AS DRIER
CANADIAN HIGH PRESSURE BUILDS INTO THE REGION. WITH COOLER TEMPS
ALOFT AND STEEP LOW LEVEL LAPSE RATES...SCT 4K-5K FT DIURNAL CUMULUS
WILL DEVELOP FOR THE LATE MORNING AND AFTERNOON HOURS. THE STEEP
LAPSE RATES AND DEEPER MIXING WILL ALLOW FOR SOME BRISK/GUSTY WEST
TO NORTHWEST WINDS THIS AFTERNOON...DIMINISHING THIS EVENING AS
TEMPS COOL AND THE MIXING DEPTH DECREASES. DIURNAL WARMING WITH
STEEP LAPSE RATES TO 900-850MB ON TUE WILL RESULT IN NORTHWEST WINDS
10-15KT G20KTS FOR TUE AFTERNOON. WITH LIGHT WINDS...CLEAR SKIES AND
CHILLY LOWS EXPECTED TUE NIGHT...WILL HAVE TO WATCH FOR VALLEY FOG
FORMATION IN THE 09Z-13Z WED MORNING PERIOD AT SITES LIKE KONA/KLSE/
KPDC/KOVS/KLNR.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
253 PM CDT MON JUN 11 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...DAS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1220 PM CDT MON JUN 11 2012
.SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT
330 AM CDT MON JUN 11 2012
MAIN FORECAST CONCERN IS ON TEMPERATURES THROUGHOUT THE SHORT TERM.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING OVER BRITISH COLUMBIA AND THE EASTERN GREAT LAKES...
WITH TROUGHING IN-BETWEEN FROM SOUTH CENTRAL CANADA INTO THE
NORTHERN PLAINS. WITHIN THIS TROUGH...A FAIRLY POTENT SHORTWAVE
STRETCHED FROM NORTHERN MN SOUTHWEST INTO SOUTHEAST SOUTH DAKOTA...
WHICH IS EVIDENT BY A DEEP DRY SLOT ON WATER VAPOR AND CLEAR SKIES
ON IR IMAGERY. 00Z ABR SOUNDING IN THE DRY SLOT WAS VERY DRY WITH A
PRECIPITABLE WATER OF 0.51 INCHES. AHEAD OF THE SHORTWAVE...AN AREA
OF CONVECTION STRETCHED FROM NORTHERN WI SOUTH INTO FAR NORTHEAST
IA/SOUTHWEST WI AND TO THE KANSAS CITY AREA. THE STRONGEST
CONVECTION HAS SHIFTED TO THE SOUTHERN END OF THIS LINE...DUE TO
BETTER LOW LEVEL CONVERGENCE SEEN IN 925 AND 850MB PROFILER DATA.
CONVECTION THAT WAS OVER MN LAST EVENING HAS WEAKENED...DUE TO THE
BETTER LOW LEVEL CONVERGENCE AND MOISTURE TRANSPORT SHIFTING
SOUTH...DECREASING INSTABILITY AHEAD OF THE CONVECTION...AS WELL AS
RAP LOW TO MID LEVEL FRONTOGENESIS FIELDS INDICATING WEAKENING
THROUGH THE NIGHT. THE ONE CAVEAT TO THIS IS AN MCV RIDING
NORTHEAST...ENTERING THE LA CROSSE AREA AS OF 08Z. ON ITS SOUTHEAST
SIDE...THE COMBINATION OF DCAPE AROUND 1000 J/KG PER RAP ANALYSIS
AND STORMS LINED ORTHOGONAL TO THE 0-3KM SHEAR VECTOR HAS HELPED
PRODUCE SOME STRONG TO POSSIBLY DAMAGING WIND GUSTS. AT THE
SURFACE...A COLD FRONT WAS PRESENT JUST BEHIND THE CONVECTION...
STRETCHING FROM NEAR THUNDER BAY ONTARIO TO LA CROSSE WI. A
SECONDARY COLD FRONT WAS PRESENT IN NORTHWEST MN. IN THE WAKE OF
THIS FRONT...SATELLITE IMAGERY AND OBSERVATION SHOWED LOW CLOUDS...
ISOLATED LIGHT SHOWERS AND MUCH COOLER TEMPERATURES IN THE 50S.
TODAY AND TONIGHT...UPPER TROUGHING OVER SOUTH CENTRAL CANADA AND
THE NORTHERN PLAINS IS FORECAST TO CONTINUE AN EAST-NORTHEASTWARD
MOVEMENT...BEING PROPELLED BY THE CURRENT POTENT SHORTWAVE IN MN AND
A SECOND ONE DROPPING DOWN THE BACK SIDE OF THE TROUGH. ALTHOUGH THE
BULK OF THE TROUGH LIFTS INTO MANITOBA...NORTHWEST ONTARIO AND LAKE
SUPERIOR...SOME OF THE TROUGHING WILL EXTEND DOWN INTO THE FORECAST
AREA BY TONIGHT. IN SUMMARY...EXPECT THE TROUGH TO BRING A COOL DOWN
FROM WHAT HAS BEEN SEEN LATELY. FIRST ISSUE TO CONTEND WITH IS THE
ONGOING SHOWERS AND EMBEDDED THUNDERSTORMS. LATEST HRRR/RAP GUIDANCE
AS WELL AS 11.00Z NAM SUGGESTS THE PRECIPITATION MAY BE COMPLETELY
EAST OF THE AREA BY 12Z. LOOKS LIKE THERE SHOULD BE A BREAK AS
INSTABILITY TRIES TO BUILD AHEAD OF THE MAIN COLD FRONT.
HOWEVER...THE MAIN COLD FRONT WILL BE EAST OF THE AREA BEFORE IT
CONVECTS...LIKELY BETWEEN 18-21Z. ATTENTION THEN TURNS TO THE
SECONDARY COLD FRONT. THIS COMES THROUGH IN THE AFTERNOON...WITH
WINDS INCREASING OUT OF THE WEST BEHIND IT. NO PRECIPITATION
ANTICIPATED...BUT SOME STRATOCUMULUS AS SEEN BACK IN THE DAKOTAS
SHOULD FILTER IN. THESE CLOUDS WILL LIKELY BECOME CELLULAR RESULTING
FROM THE STRONG JUNE SUN...THUS DISSIPATING WITH LOSS OF HEATING IN
THE EVENING. 850MB TEMPS OF 12-16C AT 18Z PLUS PLENTY OF SUN AND DRY
AIR AHEAD OF THE SECONDARY COLD FRONT SHOULD ALLOW TEMPERATURES TO
CLIMB INTO THE UPPER 70S TO MID 80S. TEMPERATURES MAY FALL SLIGHTLY
ONCE THE SECONDARY FRONT MOVES IN. BETTER TEMPERATURE FALL EXPECTED
TONIGHT AIDED BY NOCTURNAL COOLING AND CONTINUED COLD ADVECTION ON
BREEZY NORTHWEST WINDS. BY 12Z TUESDAY...850MB TEMPS ARE PROGGED TO
DROP AT LEAST DOWN TO 4-7C...AND PERHAPS SLIGHTLY COOLER AS
INDICATED BY THE NAM. WENT WITH A BLEND OF GUIDANCE FOR
LOWS...RESULTING IN UPPER 40S TO MID 50S.
TUESDAY AND TUESDAY NIGHT...UPPER FLOW IS PROGGED TO GRADUALLY TURN
ZONAL DURING THIS PERIOD AS THE UPPER TROUGHING LIFTS AWAY FROM THE
AREA. WITHIN THE ZONAL FLOW...A SHORTWAVE IS INDICATED TO REACH
CENTRAL SOUTH DAKOTA BY 12Z WEDNESDAY. SOME MID/HIGH CLOUDS
ASSOCIATED WITH ISENTROPIC LIFT AHEAD OF THIS SHORTWAVE COULD GET
INTO SOUTHEAST MN AND NORTHEAST IA LATE IN THE NIGHT. OTHERWISE...
PLENTY OF DRY AIR NOTED BY PRECIPITABLE WATER VALUES OF 0.5 INCH OR
LESS SHOULD KEEP SKIES CLEAR. ALTHOUGH THE DRY AIR AND CLEAR SKIES
ARE FAVORABLE FOR WARMING...TEMPERATURES ON TUESDAY MAY STRUGGLE
GIVEN 850MB TEMPS PROGGED TO STILL BE AT 4-7C AT 18Z. IN
FACT...TAYLOR COUNTY MAY ONLY BE AROUND 2C. THESE ARE 2 STANDARD
DEVIATIONS BELOW NORMAL. AS A RESULT...ONLY FORECAST HIGHS IN THE
MID 60S TO LOW 70S...20 DEGREES COLDER THAN YESTERDAY. DEWPOINTS ARE
LIKELY TO TANK FROM MIXING OF THE DRY AIR. SHOULD BE BREEZY TOO IN
THE MORNING ADDING AN EXTRA CHILL BEFORE SURFACE HIGH PRESSURE
BUILDS OVERHEAD IN THE EVENING TO CALM WINDS. THIS SETS THE STAGE
FOR GOOD RADIATIONAL COOLING TUESDAY NIGHT...ESPECIALLY IN
WISCONSIN. WOULD NOT BE SURPRISED TO HAVE SOME UPPER 30S FOR LOWS IN
THE TYPICAL COLD SPOTS. WARMER READINGS ARE EXPECTED WEST OF THE
MISSISSIPPI RIVER WHERE RETURN FLOW AND CLOUDS COME IN.
WEDNESDAY AND WEDNESDAY NIGHT...UPPER LEVEL FLOW LOOKS TO AMPLIFY
AGAIN AS TROUGHING DROPS DOWN INTO SOUTHWEST CANADA AND THE PACIFIC
NORTHWEST BY 12Z THURSDAY. THIS AMPLIFICATION SHOULD HELP TAKE THE
SHORTWAVE THAT WAS COMING INTO SOUTH DAKOTA TUESDAY NIGHT AND LIFT
IT WELL NORTHWEST OF THE AREA. BY 00Z THURSDAY...ALL MODELS HAVE IT
CROSSING CENTRAL OR NORTHERN MN. GIVEN DRY LOW LEVEL AIRMASS IN
PLACE BY THE SURFACE HIGH PRESSURE AREA...AS WELL AS THE TRACK OF
THE SHORTWAVE...NOT ANTICIPATING ANY PRECIPITATION TO SPREAD INTO
THE FORECAST AREA. HOWEVER...CLOUD COVER IS AN ISSUE. INCREASING
305-310 K ISENTROPIC LIFT EAST OF THE SHORTWAVE SHOULD SPREAD MID
AND HIGH CLOUDS ACROSS MUCH OF THE AREA ON WEDNESDAY. THESE CLOUDS
MAY LIMITING HEATING SOMEWHAT...DESPITE WARMER 850MB TEMPS IN THE
8-12C RANGE. KEPT HIGHS IN THE LOW TO MID 70S...WHICH ARE ABOUT 5
DEGREES COOLER THAN WHAT THEY COULD BE IF FULL SUN WAS OBSERVED. THE
CLOUDS DO LOOK TO CLEAR OUT WEDNESDAY NIGHT AS THE SHORTWAVE HEADS
INTO ONTARIO. FOLLOWED A BLEND OF GUIDANCE FOR LOWS GIVEN NO STRONG
SIGNAL TO GO COLDER OR WARMER.
.LONG TERM...THURSDAY THROUGH SUNDAY NIGHT
330 AM CDT MON JUN 11 2012
11.00Z ECMWF/CANADIAN/GFS AND GFS ENSEMBLES REMAIN IN PRETTY GOOD
AGREEMENT ON THE UPPER LEVEL PATTERN...AND IN FACT ARE IN BETTER
AGREEMENT NOW COMPARED TO YESTERDAY. CONSENSUS IS THAT TROUGHING
WILL HOLD OVER THE NORTHWESTERN U.S. THROUGH MUCH OF THE LONG TERM
PERIOD...RESULTING IN STRENGTHENING RIDGING DOWNSTREAM OVER THE
WESTERN GREAT LAKES. IN FACT...BY SUNDAY NIGHT WHEN MODELS HAVE THE
TROUGH DIGGING MORE INTO THE NORTHERN ROCKIES...THE RIDGE DOWNSTREAM
REALLY STRENGTHENS. IT APPEARS THAT MOST OF THE SHORTWAVES EJECTING
OUT OF THE TROUGH WILL END UP STAYING MOSTLY TO THE NORTHWEST OF THE
AREA. THUS...OVERALL MUCH OF THIS LONG TERM FORECAST LOOKS DRY. HAVE
MAINTAINED SOME 20-30 PERCENT CHANCES OVER NORTHWEST PORTIONS OF THE
AREA ON SATURDAY...NORTH OF I-90 SATURDAY NIGHT AND ACROSS THE
ENTIRE AREA SUNDAY INTO SUNDAY NIGHT. THESE MOSTLY STEM FROM BEING
ON THE NOSE OF SOME MOISTURE TRANSPORT AND SHORTWAVES COMING CLOSE
TO THE AREA. HOWEVER...IT IS POSSIBLE THESE CHANCES MAY BE ABLE TO
BE REMOVED IN LATER FORECASTS WITH MODELS TRENDING DRIER. ONE OTHER
PERIOD TO WATCH IS THURSDAY WITH THE 11.00Z ECMWF BEING REALLY
AGGRESSIVE IN DEVELOPING PRECIPITATION OVER MN. THIS APPEARS TO BE
RELATED TO A SURGE OF WARM...MOIST AIR OCCURRING WITH THE BUILDING
RIDGING. GIVEN THAT THE MODEL DOES NOT BRING THE PRECIPITATION INTO
THE AREA AND OTHER MODELS SUGGESTING DRIER...HAVE KEPT THURSDAY DRY.
WHAT COULD BE MORE SIGNIFICANT FOR THE LONG TERM FORECAST IS
TEMPERATURES. WITH THE AREA NOW STRONGLY FORECAST TO BE UNDER
RIDGING...AND IN BROAD BREEZY SOUTHERLY FLOW...WE COULD BE DEALING
WITH ANOTHER LONG STRETCH OF 80S AND PERHAPS 90S. NEW ECMWF REALLY
CAME IN WARM...WITH 850MB TEMPS FRIDAY THROUGH MONDAY HOVERING
AROUND 20C OR SO...RESULTING IN HIGHS OF 90-95. HAVE BOOSTED
TEMPERATURES UP ABOVE THE CONSENSUS AND THESE MAY STILL BE TOO
COOL.
&&
.AVIATION...THIS AFTERNOON THROUGH TUESDAY
1220 PM CDT MON JUN 11 2012
QUIET...GOOD VFR PERIOD FOR THIS AFTERNOON THRU TUESDAY AS DRIER
CANADIAN HIGH PRESSURE BUILDS INTO THE REGION. WITH COOLER TEMPS
ALOFT AND STEEP LOW LEVEL LAPSE RATES...SCT 4K-5K FT DIURNAL CUMULUS
WILL DEVELOP FOR THE LATE MORNING AND AFTERNOON HOURS. THE STEEP
LAPSE RATES AND DEEPER MIXING WILL ALLOW FOR SOME BRISK/GUSTY WEST
TO NORTHWEST WINDS THIS AFTERNOON...DIMINISHING THIS EVENING AS
TEMPS COOL AND THE MIXING DEPTH DECREASES. DIURNAL WARMING WITH
STEEP LAPSE RATES TO 900-850MB ON TUE WILL RESULT IN NORTHWEST WINDS
10-15KT G20KTS FOR TUE AFTERNOON. WITH LIGHT WINDS...CLEAR SKIES AND
CHILLY LOWS EXPECTED TUE NIGHT...WILL HAVE TO WATCH FOR VALLEY FOG
FORMATION IN THE 09Z-13Z WED MORNING PERIOD AT SITES LIKE KONA/KLSE/
KPDC/KOVS/KLNR.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
330 AM CDT MON JUN 11 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...DAS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
645 AM CDT MON JUN 11 2012
.SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT
330 AM CDT MON JUN 11 2012
MAIN FORECAST CONCERN IS ON TEMPERATURES THROUGHOUT THE SHORT TERM.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING OVER BRITISH COLUMBIA AND THE EASTERN GREAT LAKES...
WITH TROUGHING IN-BETWEEN FROM SOUTH CENTRAL CANADA INTO THE
NORTHERN PLAINS. WITHIN THIS TROUGH...A FAIRLY POTENT SHORTWAVE
STRETCHED FROM NORTHERN MN SOUTHWEST INTO SOUTHEAST SOUTH DAKOTA...
WHICH IS EVIDENT BY A DEEP DRY SLOT ON WATER VAPOR AND CLEAR SKIES
ON IR IMAGERY. 00Z ABR SOUNDING IN THE DRY SLOT WAS VERY DRY WITH A
PRECIPITABLE WATER OF 0.51 INCHES. AHEAD OF THE SHORTWAVE...AN AREA
OF CONVECTION STRETCHED FROM NORTHERN WI SOUTH INTO FAR NORTHEAST
IA/SOUTHWEST WI AND TO THE KANSAS CITY AREA. THE STRONGEST
CONVECTION HAS SHIFTED TO THE SOUTHERN END OF THIS LINE...DUE TO
BETTER LOW LEVEL CONVERGENCE SEEN IN 925 AND 850MB PROFILER DATA.
CONVECTION THAT WAS OVER MN LAST EVENING HAS WEAKENED...DUE TO THE
BETTER LOW LEVEL CONVERGENCE AND MOISTURE TRANSPORT SHIFTING
SOUTH...DECREASING INSTABILITY AHEAD OF THE CONVECTION...AS WELL AS
RAP LOW TO MID LEVEL FRONTOGENESIS FIELDS INDICATING WEAKENING
THROUGH THE NIGHT. THE ONE CAVEAT TO THIS IS AN MCV RIDING
NORTHEAST...ENTERING THE LA CROSSE AREA AS OF 08Z. ON ITS SOUTHEAST
SIDE...THE COMBINATION OF DCAPE AROUND 1000 J/KG PER RAP ANALYSIS
AND STORMS LINED ORTHOGONAL TO THE 0-3KM SHEAR VECTOR HAS HELPED
PRODUCE SOME STRONG TO POSSIBLY DAMAGING WIND GUSTS. AT THE
SURFACE...A COLD FRONT WAS PRESENT JUST BEHIND THE CONVECTION...
STRETCHING FROM NEAR THUNDER BAY ONTARIO TO LA CROSSE WI. A
SECONDARY COLD FRONT WAS PRESENT IN NORTHWEST MN. IN THE WAKE OF
THIS FRONT...SATELLITE IMAGERY AND OBSERVATION SHOWED LOW CLOUDS...
ISOLATED LIGHT SHOWERS AND MUCH COOLER TEMPERATURES IN THE 50S.
TODAY AND TONIGHT...UPPER TROUGHING OVER SOUTH CENTRAL CANADA AND
THE NORTHERN PLAINS IS FORECAST TO CONTINUE AN EAST-NORTHEASTWARD
MOVEMENT...BEING PROPELLED BY THE CURRENT POTENT SHORTWAVE IN MN AND
A SECOND ONE DROPPING DOWN THE BACK SIDE OF THE TROUGH. ALTHOUGH THE
BULK OF THE TROUGH LIFTS INTO MANITOBA...NORTHWEST ONTARIO AND LAKE
SUPERIOR...SOME OF THE TROUGHING WILL EXTEND DOWN INTO THE FORECAST
AREA BY TONIGHT. IN SUMMARY...EXPECT THE TROUGH TO BRING A COOL DOWN
FROM WHAT HAS BEEN SEEN LATELY. FIRST ISSUE TO CONTEND WITH IS THE
ONGOING SHOWERS AND EMBEDDED THUNDERSTORMS. LATEST HRRR/RAP GUIDANCE
AS WELL AS 11.00Z NAM SUGGESTS THE PRECIPITATION MAY BE COMPLETELY
EAST OF THE AREA BY 12Z. LOOKS LIKE THERE SHOULD BE A BREAK AS
INSTABILITY TRIES TO BUILD AHEAD OF THE MAIN COLD FRONT.
HOWEVER...THE MAIN COLD FRONT WILL BE EAST OF THE AREA BEFORE IT
CONVECTS...LIKELY BETWEEN 18-21Z. ATTENTION THEN TURNS TO THE
SECONDARY COLD FRONT. THIS COMES THROUGH IN THE AFTERNOON...WITH
WINDS INCREASING OUT OF THE WEST BEHIND IT. NO PRECIPITATION
ANTICIPATED...BUT SOME STRATOCUMULUS AS SEEN BACK IN THE DAKOTAS
SHOULD FILTER IN. THESE CLOUDS WILL LIKELY BECOME CELLULAR RESULTING
FROM THE STRONG JUNE SUN...THUS DISSIPATING WITH LOSS OF HEATING IN
THE EVENING. 850MB TEMPS OF 12-16C AT 18Z PLUS PLENTY OF SUN AND DRY
AIR AHEAD OF THE SECONDARY COLD FRONT SHOULD ALLOW TEMPERATURES TO
CLIMB INTO THE UPPER 70S TO MID 80S. TEMPERATURES MAY FALL SLIGHTLY
ONCE THE SECONDARY FRONT MOVES IN. BETTER TEMPERATURE FALL EXPECTED
TONIGHT AIDED BY NOCTURNAL COOLING AND CONTINUED COLD ADVECTION ON
BREEZY NORTHWEST WINDS. BY 12Z TUESDAY...850MB TEMPS ARE PROGGED TO
DROP AT LEAST DOWN TO 4-7C...AND PERHAPS SLIGHTLY COOLER AS
INDICATED BY THE NAM. WENT WITH A BLEND OF GUIDANCE FOR
LOWS...RESULTING IN UPPER 40S TO MID 50S.
TUESDAY AND TUESDAY NIGHT...UPPER FLOW IS PROGGED TO GRADUALLY TURN
ZONAL DURING THIS PERIOD AS THE UPPER TROUGHING LIFTS AWAY FROM THE
AREA. WITHIN THE ZONAL FLOW...A SHORTWAVE IS INDICATED TO REACH
CENTRAL SOUTH DAKOTA BY 12Z WEDNESDAY. SOME MID/HIGH CLOUDS
ASSOCIATED WITH ISENTROPIC LIFT AHEAD OF THIS SHORTWAVE COULD GET
INTO SOUTHEAST MN AND NORTHEAST IA LATE IN THE NIGHT. OTHERWISE...
PLENTY OF DRY AIR NOTED BY PRECIPITABLE WATER VALUES OF 0.5 INCH OR
LESS SHOULD KEEP SKIES CLEAR. ALTHOUGH THE DRY AIR AND CLEAR SKIES
ARE FAVORABLE FOR WARMING...TEMPERATURES ON TUESDAY MAY STRUGGLE
GIVEN 850MB TEMPS PROGGED TO STILL BE AT 4-7C AT 18Z. IN
FACT...TAYLOR COUNTY MAY ONLY BE AROUND 2C. THESE ARE 2 STANDARD
DEVIATIONS BELOW NORMAL. AS A RESULT...ONLY FORECAST HIGHS IN THE
MID 60S TO LOW 70S...20 DEGREES COLDER THAN YESTERDAY. DEWPOINTS ARE
LIKELY TO TANK FROM MIXING OF THE DRY AIR. SHOULD BE BREEZY TOO IN
THE MORNING ADDING AN EXTRA CHILL BEFORE SURFACE HIGH PRESSURE
BUILDS OVERHEAD IN THE EVENING TO CALM WINDS. THIS SETS THE STAGE
FOR GOOD RADIATIONAL COOLING TUESDAY NIGHT...ESPECIALLY IN
WISCONSIN. WOULD NOT BE SURPRISED TO HAVE SOME UPPER 30S FOR LOWS IN
THE TYPICAL COLD SPOTS. WARMER READINGS ARE EXPECTED WEST OF THE
MISSISSIPPI RIVER WHERE RETURN FLOW AND CLOUDS COME IN.
WEDNESDAY AND WEDNESDAY NIGHT...UPPER LEVEL FLOW LOOKS TO AMPLIFY
AGAIN AS TROUGHING DROPS DOWN INTO SOUTHWEST CANADA AND THE PACIFIC
NORTHWEST BY 12Z THURSDAY. THIS AMPLIFICATION SHOULD HELP TAKE THE
SHORTWAVE THAT WAS COMING INTO SOUTH DAKOTA TUESDAY NIGHT AND LIFT
IT WELL NORTHWEST OF THE AREA. BY 00Z THURSDAY...ALL MODELS HAVE IT
CROSSING CENTRAL OR NORTHERN MN. GIVEN DRY LOW LEVEL AIRMASS IN
PLACE BY THE SURFACE HIGH PRESSURE AREA...AS WELL AS THE TRACK OF
THE SHORTWAVE...NOT ANTICIPATING ANY PRECIPITATION TO SPREAD INTO
THE FORECAST AREA. HOWEVER...CLOUD COVER IS AN ISSUE. INCREASING
305-310 K ISENTROPIC LIFT EAST OF THE SHORTWAVE SHOULD SPREAD MID
AND HIGH CLOUDS ACROSS MUCH OF THE AREA ON WEDNESDAY. THESE CLOUDS
MAY LIMITING HEATING SOMEWHAT...DESPITE WARMER 850MB TEMPS IN THE
8-12C RANGE. KEPT HIGHS IN THE LOW TO MID 70S...WHICH ARE ABOUT 5
DEGREES COOLER THAN WHAT THEY COULD BE IF FULL SUN WAS OBSERVED. THE
CLOUDS DO LOOK TO CLEAR OUT WEDNESDAY NIGHT AS THE SHORTWAVE HEADS
INTO ONTARIO. FOLLOWED A BLEND OF GUIDANCE FOR LOWS GIVEN NO STRONG
SIGNAL TO GO COLDER OR WARMER.
.LONG TERM...THURSDAY THROUGH SUNDAY NIGHT
330 AM CDT MON JUN 11 2012
11.00Z ECMWF/CANADIAN/GFS AND GFS ENSEMBLES REMAIN IN PRETTY GOOD
AGREEMENT ON THE UPPER LEVEL PATTERN...AND IN FACT ARE IN BETTER
AGREEMENT NOW COMPARED TO YESTERDAY. CONSENSUS IS THAT TROUGHING
WILL HOLD OVER THE NORTHWESTERN U.S. THROUGH MUCH OF THE LONG TERM
PERIOD...RESULTING IN STRENGTHENING RIDGING DOWNSTREAM OVER THE
WESTERN GREAT LAKES. IN FACT...BY SUNDAY NIGHT WHEN MODELS HAVE THE
TROUGH DIGGING MORE INTO THE NORTHERN ROCKIES...THE RIDGE DOWNSTREAM
REALLY STRENGTHENS. IT APPEARS THAT MOST OF THE SHORTWAVES EJECTING
OUT OF THE TROUGH WILL END UP STAYING MOSTLY TO THE NORTHWEST OF THE
AREA. THUS...OVERALL MUCH OF THIS LONG TERM FORECAST LOOKS DRY. HAVE
MAINTAINED SOME 20-30 PERCENT CHANCES OVER NORTHWEST PORTIONS OF THE
AREA ON SATURDAY...NORTH OF I-90 SATURDAY NIGHT AND ACROSS THE
ENTIRE AREA SUNDAY INTO SUNDAY NIGHT. THESE MOSTLY STEM FROM BEING
ON THE NOSE OF SOME MOISTURE TRANSPORT AND SHORTWAVES COMING CLOSE
TO THE AREA. HOWEVER...IT IS POSSIBLE THESE CHANCES MAY BE ABLE TO
BE REMOVED IN LATER FORECASTS WITH MODELS TRENDING DRIER. ONE OTHER
PERIOD TO WATCH IS THURSDAY WITH THE 11.00Z ECMWF BEING REALLY
AGGRESSIVE IN DEVELOPING PRECIPITATION OVER MN. THIS APPEARS TO BE
RELATED TO A SURGE OF WARM...MOIST AIR OCCURRING WITH THE BUILDING
RIDGING. GIVEN THAT THE MODEL DOES NOT BRING THE PRECIPITATION INTO
THE AREA AND OTHER MODELS SUGGESTING DRIER...HAVE KEPT THURSDAY DRY.
WHAT COULD BE MORE SIGNIFICANT FOR THE LONG TERM FORECAST IS
TEMPERATURES. WITH THE AREA NOW STRONGLY FORECAST TO BE UNDER
RIDGING...AND IN BROAD BREEZY SOUTHERLY FLOW...WE COULD BE DEALING
WITH ANOTHER LONG STRETCH OF 80S AND PERHAPS 90S. NEW ECMWF REALLY
CAME IN WARM...WITH 850MB TEMPS FRIDAY THROUGH MONDAY HOVERING
AROUND 20C OR SO...RESULTING IN HIGHS OF 90-95. HAVE BOOSTED
TEMPERATURES UP ABOVE THE CONSENSUS AND THESE MAY STILL BE TOO
COOL.
&&
.AVIATION...TODAY AND TONIGHT
645 AM CDT MON JUN 11 2012
CONCERNS DEAL WITH A FEW LOW CLOUDS THIS MORNING...THEN WINDS
THROUGH THE REST OF TODAY.
CURRENTLY WATCHING A COLD FRONT MOVE EAST OF THE MISSISSIPPI INTO
CENTRAL WISCONSIN...BRINGING LINE OF SHRA/TS WITH IT. LOOSE
GRADIENT IMMEDIATELY BEHIND THE FRONT PRODUCING LIGHT WINDS AT
KRST/KLSE TAF SITES EARLY THIS MORNING. LIGHTER WINDS AND RESIDUAL
LOWER BOUNDARY LAYER MOISTURE FROM OVERNIGHT RAINFALL WAS
ALLOWING POCKETS OF STRATUS TO DEVELOP. SO FAR...STRATUS WITH BASES
AOB 600 FEET SCATTERED IN NATURE AND IS EXPECTED TO DISSIPATE
13-14Z AS WINDS START TO VEER TO THE WEST AND DRYING OF THE
BOUNDARY LAYER TAKES PLACE. LOOK FOR THE PRESSURE GRADIENT AND
RESULTANT WEST WINDS TO INCREASE BY 16Z WITH GUSTS IN THE 20-30KT
RANGE PREVALENT BY AFTERNOON. SCATTERED CUMULUS WITH BASES 4-5KFT
EXPECTED TO DEVELOP BY MIDDAY AS AN UPPER LEVEL TROUGH SWINGS
ACROSS THE DAKOTAS INTO THE UPPER MISSISSIPPI RIVER VALLEY REGION.
LOOK FOR THE WINDS TO SUBSIDE AND CUMULUS TO DISSIPATE TOWARD
SUNSET. MOSTLY CLEAR/VFR CONDITIONS EXPECTED OVERNIGHT AS HIGH
PRESSURE BUILDS IN FROM THE NORTHERN PLAINS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
330 AM CDT MON JUN 11 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...DAS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
330 AM CDT MON JUN 11 2012
.SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT
330 AM CDT MON JUN 11 2012
MAIN FORECAST CONCERN IS ON TEMPERATURES THROUGHOUT THE SHORT TERM.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING OVER BRITISH COLUMBIA AND THE EASTERN GREAT LAKES...
WITH TROUGHING IN-BETWEEN FROM SOUTH CENTRAL CANADA INTO THE
NORTHERN PLAINS. WITHIN THIS TROUGH...A FAIRLY POTENT SHORTWAVE
STRETCHED FROM NORTHERN MN SOUTHWEST INTO SOUTHEAST SOUTH DAKOTA...
WHICH IS EVIDENT BY A DEEP DRY SLOT ON WATER VAPOR AND CLEAR SKIES
ON IR IMAGERY. 00Z ABR SOUNDING IN THE DRY SLOT WAS VERY DRY WITH A
PRECIPITABLE WATER OF 0.51 INCHES. AHEAD OF THE SHORTWAVE...AN AREA
OF CONVECTION STRETCHED FROM NORTHERN WI SOUTH INTO FAR NORTHEAST
IA/SOUTHWEST WI AND TO THE KANSAS CITY AREA. THE STRONGEST
CONVECTION HAS SHIFTED TO THE SOUTHERN END OF THIS LINE...DUE TO
BETTER LOW LEVEL CONVERGENCE SEEN IN 925 AND 850MB PROFILER DATA.
CONVECTION THAT WAS OVER MN LAST EVENING HAS WEAKENED...DUE TO THE
BETTER LOW LEVEL CONVERGENCE AND MOISTURE TRANSPORT SHIFTING
SOUTH...DECREASING INSTABILITY AHEAD OF THE CONVECTION...AS WELL AS
RAP LOW TO MID LEVEL FRONTOGENESIS FIELDS INDICATING WEAKENING
THROUGH THE NIGHT. THE ONE CAVEAT TO THIS IS AN MCV RIDING
NORTHEAST...ENTERING THE LA CROSSE AREA AS OF 08Z. ON ITS SOUTHEAST
SIDE...THE COMBINATION OF DCAPE AROUND 1000 J/KG PER RAP ANALYSIS
AND STORMS LINED ORTHOGONAL TO THE 0-3KM SHEAR VECTOR HAS HELPED
PRODUCE SOME STRONG TO POSSIBLY DAMAGING WIND GUSTS. AT THE
SURFACE...A COLD FRONT WAS PRESENT JUST BEHIND THE CONVECTION...
STRETCHING FROM NEAR THUNDER BAY ONTARIO TO LA CROSSE WI. A
SECONDARY COLD FRONT WAS PRESENT IN NORTHWEST MN. IN THE WAKE OF
THIS FRONT...SATELLITE IMAGERY AND OBSERVATION SHOWED LOW CLOUDS...
ISOLATED LIGHT SHOWERS AND MUCH COOLER TEMPERATURES IN THE 50S.
TODAY AND TONIGHT...UPPER TROUGHING OVER SOUTH CENTRAL CANADA AND
THE NORTHERN PLAINS IS FORECAST TO CONTINUE AN EAST-NORTHEASTWARD
MOVEMENT...BEING PROPELLED BY THE CURRENT POTENT SHORTWAVE IN MN AND
A SECOND ONE DROPPING DOWN THE BACK SIDE OF THE TROUGH. ALTHOUGH THE
BULK OF THE TROUGH LIFTS INTO MANITOBA...NORTHWEST ONTARIO AND LAKE
SUPERIOR...SOME OF THE TROUGHING WILL EXTEND DOWN INTO THE FORECAST
AREA BY TONIGHT. IN SUMMARY...EXPECT THE TROUGH TO BRING A COOL DOWN
FROM WHAT HAS BEEN SEEN LATELY. FIRST ISSUE TO CONTEND WITH IS THE
ONGOING SHOWERS AND EMBEDDED THUNDERSTORMS. LATEST HRRR/RAP GUIDANCE
AS WELL AS 11.00Z NAM SUGGESTS THE PRECIPITATION MAY BE COMPLETELY
EAST OF THE AREA BY 12Z. LOOKS LIKE THERE SHOULD BE A BREAK AS
INSTABILITY TRIES TO BUILD AHEAD OF THE MAIN COLD FRONT.
HOWEVER...THE MAIN COLD FRONT WILL BE EAST OF THE AREA BEFORE IT
CONVECTS...LIKELY BETWEEN 18-21Z. ATTENTION THEN TURNS TO THE
SECONDARY COLD FRONT. THIS COMES THROUGH IN THE AFTERNOON...WITH
WINDS INCREASING OUT OF THE WEST BEHIND IT. NO PRECIPITATION
ANTICIPATED...BUT SOME STRATOCUMULUS AS SEEN BACK IN THE DAKOTAS
SHOULD FILTER IN. THESE CLOUDS WILL LIKELY BECOME CELLULAR RESULTING
FROM THE STRONG JUNE SUN...THUS DISSIPATING WITH LOSS OF HEATING IN
THE EVENING. 850MB TEMPS OF 12-16C AT 18Z PLUS PLENTY OF SUN AND DRY
AIR AHEAD OF THE SECONDARY COLD FRONT SHOULD ALLOW TEMPERATURES TO
CLIMB INTO THE UPPER 70S TO MID 80S. TEMPERATURES MAY FALL SLIGHTLY
ONCE THE SECONDARY FRONT MOVES IN. BETTER TEMPERATURE FALL EXPECTED
TONIGHT AIDED BY NOCTURNAL COOLING AND CONTINUED COLD ADVECTION ON
BREEZY NORTHWEST WINDS. BY 12Z TUESDAY...850MB TEMPS ARE PROGGED TO
DROP AT LEAST DOWN TO 4-7C...AND PERHAPS SLIGHTLY COOLER AS
INDICATED BY THE NAM. WENT WITH A BLEND OF GUIDANCE FOR
LOWS...RESULTING IN UPPER 40S TO MID 50S.
TUESDAY AND TUESDAY NIGHT...UPPER FLOW IS PROGGED TO GRADUALLY TURN
ZONAL DURING THIS PERIOD AS THE UPPER TROUGHING LIFTS AWAY FROM THE
AREA. WITHIN THE ZONAL FLOW...A SHORTWAVE IS INDICATED TO REACH
CENTRAL SOUTH DAKOTA BY 12Z WEDNESDAY. SOME MID/HIGH CLOUDS
ASSOCIATED WITH ISENTROPIC LIFT AHEAD OF THIS SHORTWAVE COULD GET
INTO SOUTHEAST MN AND NORTHEAST IA LATE IN THE NIGHT. OTHERWISE...
PLENTY OF DRY AIR NOTED BY PRECIPITABLE WATER VALUES OF 0.5 INCH OR
LESS SHOULD KEEP SKIES CLEAR. ALTHOUGH THE DRY AIR AND CLEAR SKIES
ARE FAVORABLE FOR WARMING...TEMPERATURES ON TUESDAY MAY STRUGGLE
GIVEN 850MB TEMPS PROGGED TO STILL BE AT 4-7C AT 18Z. IN
FACT...TAYLOR COUNTY MAY ONLY BE AROUND 2C. THESE ARE 2 STANDARD
DEVIATIONS BELOW NORMAL. AS A RESULT...ONLY FORECAST HIGHS IN THE
MID 60S TO LOW 70S...20 DEGREES COLDER THAN YESTERDAY. DEWPOINTS ARE
LIKELY TO TANK FROM MIXING OF THE DRY AIR. SHOULD BE BREEZY TOO IN
THE MORNING ADDING AN EXTRA CHILL BEFORE SURFACE HIGH PRESSURE
BUILDS OVERHEAD IN THE EVENING TO CALM WINDS. THIS SETS THE STAGE
FOR GOOD RADIATIONAL COOLING TUESDAY NIGHT...ESPECIALLY IN
WISCONSIN. WOULD NOT BE SURPRISED TO HAVE SOME UPPER 30S FOR LOWS IN
THE TYPICAL COLD SPOTS. WARMER READINGS ARE EXPECTED WEST OF THE
MISSISSIPPI RIVER WHERE RETURN FLOW AND CLOUDS COME IN.
WEDNESDAY AND WEDNESDAY NIGHT...UPPER LEVEL FLOW LOOKS TO AMPLIFY
AGAIN AS TROUGHING DROPS DOWN INTO SOUTHWEST CANADA AND THE PACIFIC
NORTHWEST BY 12Z THURSDAY. THIS AMPLIFICATION SHOULD HELP TAKE THE
SHORTWAVE THAT WAS COMING INTO SOUTH DAKOTA TUESDAY NIGHT AND LIFT
IT WELL NORTHWEST OF THE AREA. BY 00Z THURSDAY...ALL MODELS HAVE IT
CROSSING CENTRAL OR NORTHERN MN. GIVEN DRY LOW LEVEL AIRMASS IN
PLACE BY THE SURFACE HIGH PRESSURE AREA...AS WELL AS THE TRACK OF
THE SHORTWAVE...NOT ANTICIPATING ANY PRECIPITATION TO SPREAD INTO
THE FORECAST AREA. HOWEVER...CLOUD COVER IS AN ISSUE. INCREASING
305-310 K ISENTROPIC LIFT EAST OF THE SHORTWAVE SHOULD SPREAD MID
AND HIGH CLOUDS ACROSS MUCH OF THE AREA ON WEDNESDAY. THESE CLOUDS
MAY LIMITING HEATING SOMEWHAT...DESPITE WARMER 850MB TEMPS IN THE
8-12C RANGE. KEPT HIGHS IN THE LOW TO MID 70S...WHICH ARE ABOUT 5
DEGREES COOLER THAN WHAT THEY COULD BE IF FULL SUN WAS OBSERVED. THE
CLOUDS DO LOOK TO CLEAR OUT WEDNESDAY NIGHT AS THE SHORTWAVE HEADS
INTO ONTARIO. FOLLOWED A BLEND OF GUIDANCE FOR LOWS GIVEN NO STRONG
SIGNAL TO GO COLDER OR WARMER.
.LONG TERM...THURSDAY THROUGH SUNDAY NIGHT
330 AM CDT MON JUN 11 2012
11.00Z ECMWF/CANADIAN/GFS AND GFS ENSEMBLES REMAIN IN PRETTY GOOD
AGREEMENT ON THE UPPER LEVEL PATTERN...AND IN FACT ARE IN BETTER
AGREEMENT NOW COMPARED TO YESTERDAY. CONSENSUS IS THAT TROUGHING
WILL HOLD OVER THE NORTHWESTERN U.S. THROUGH MUCH OF THE LONG TERM
PERIOD...RESULTING IN STRENGTHENING RIDGING DOWNSTREAM OVER THE
WESTERN GREAT LAKES. IN FACT...BY SUNDAY NIGHT WHEN MODELS HAVE THE
TROUGH DIGGING MORE INTO THE NORTHERN ROCKIES...THE RIDGE DOWNSTREAM
REALLY STRENGTHENS. IT APPEARS THAT MOST OF THE SHORTWAVES EJECTING
OUT OF THE TROUGH WILL END UP STAYING MOSTLY TO THE NORTHWEST OF THE
AREA. THUS...OVERALL MUCH OF THIS LONG TERM FORECAST LOOKS DRY. HAVE
MAINTAINED SOME 20-30 PERCENT CHANCES OVER NORTHWEST PORTIONS OF THE
AREA ON SATURDAY...NORTH OF I-90 SATURDAY NIGHT AND ACROSS THE
ENTIRE AREA SUNDAY INTO SUNDAY NIGHT. THESE MOSTLY STEM FROM BEING
ON THE NOSE OF SOME MOISTURE TRANSPORT AND SHORTWAVES COMING CLOSE
TO THE AREA. HOWEVER...IT IS POSSIBLE THESE CHANCES MAY BE ABLE TO
BE REMOVED IN LATER FORECASTS WITH MODELS TRENDING DRIER. ONE OTHER
PERIOD TO WATCH IS THURSDAY WITH THE 11.00Z ECMWF BEING REALLY
AGGRESSIVE IN DEVELOPING PRECIPITATION OVER MN. THIS APPEARS TO BE
RELATED TO A SURGE OF WARM...MOIST AIR OCCURRING WITH THE BUILDING
RIDGING. GIVEN THAT THE MODEL DOES NOT BRING THE PRECIPITATION INTO
THE AREA AND OTHER MODELS SUGGESTING DRIER...HAVE KEPT THURSDAY DRY.
WHAT COULD BE MORE SIGNIFICANT FOR THE LONG TERM FORECAST IS
TEMPERATURES. WITH THE AREA NOW STRONGLY FORECAST TO BE UNDER
RIDGING...AND IN BROAD BREEZY SOUTHERLY FLOW...WE COULD BE DEALING
WITH ANOTHER LONG STRETCH OF 80S AND PERHAPS 90S. NEW ECMWF REALLY
CAME IN WARM...WITH 850MB TEMPS FRIDAY THROUGH MONDAY HOVERING
AROUND 20C OR SO...RESULTING IN HIGHS OF 90-95. HAVE BOOSTED
TEMPERATURES UP ABOVE THE CONSENSUS AND THESE MAY STILL BE TOO
COOL.
&&
.AVIATION...THROUGH 06Z TUESDAY
1110 PM CDT SUN JUN 10 2012
SHOWERS AND THUNDERSTORMS WILL MOVE EAST ALONG AND JUST BEHIND A
COLD FRONT THAT CURRENTLY EXTENDS FROM THE TWIN CITIES DOWN TO
MASON CITY. IT LOOKS LIKE IT WILL BE ABOUT A 3-4 HOUR PERIOD OF
CONVECTION WITH SOME INTERMITTENT THUNDERSTORMS POSSIBLE.
CONDITIONS WILL MAINLY BE VFR THOUGH CEILINGS MAY DROP DOWN TO
BETWEEN 2-3KFT FOR A PERIOD AS THE SHOWERS AND STORMS MOVE THROUGH
OVERNIGHT. WINDS WILL GO LIGHT AFTER THE FRONT AND CONVECTION
PASSES THROUGH...BUT CLOUD COVER WILL LIKELY PERSIST THROUGH
DAYBREAK. THUS...AM NOT EXPECTING ANY FOG TO FORM AT RST OR LSE
THIS MORNING. WINDS WILL INCREASE INTO THE 20-25KT RANGE THIS
AFTERNOON AS A SECONDARY COLD FRONT MOVES THROUGH THE REGION.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
330 AM CDT MON JUN 11 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...HALBACH
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
135 AM EDT WED JUN 13 2012
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 325 PM EDT TUE JUN 12 2012
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW PROGRESSIVE UPR
TROF EXTENDING FM HUDSON BAY INTO THE GRT LKS MOVING E IN ADVANCE OF
UPR RDG OVER WRN CANADA. SHRTWV EMBEDDED WITHIN THIS TROF BROUGHT
LOTS OF CLDS AND SOME -SHRA TO MAINLY THE NRN TIER INTO EARLY
AFTN... BUT TREND THIS AFTN HAS BEEN FOR MORE SUNSHINE AS DNVA/
LARGER SCALE QVECTOR DVGC/MORE ACYC FLOW AND DRIER AIR SHOWN ON THE
12Z INL RAOB IS FOLLOWING IN THE WAKE OF THAT DISTURBANCE IN ADVANCE
OF SFC HI PRES CENTERED OVER SE SDAKOTA. SKIES ARE MOCLR FM THE HI
CENTER STRETCHING TOWARD LK WINNIPEG...WHERE THE 12Z RAOB AT THE PAS
IN MANITOBA SHOWS A PWAT OF 0.28 INCH. SFC DEWPTS THIS AFTN HAVE
MIXED OUT INTO THE LO-MID 30S IN THIS UPSTREAM AIRMASS. MORE CLDS
ARE PRESENT A BIT FARTHER W IN THE NRN PLAINS IN THE RETURN SW FLOW
ARND THE SFC HI AND IN ADVANCE OF SHRTWV TRACKING E ACRS
WYOMING/MONTANA. 12Z BIS RAOB SHOWS MORE MSTR/PWAT OF 0.70 INCH NEAR
THE WAD CLD BAND.
MAIN FCST CONCERNS IN THE SHORT TERM REVOLVE ARND CLRG TRENDS THIS
AFTN AND THEN TEMPS/POTENTIAL FOR FROST TNGT.
TNGT...SFC HI PRES IS FCST TO MOVE E AND TO OVER NRN LWR MI BY 12Z
WED. EXPECT ANY LINGERING CLDS TO DSPT LATE THIS AFTN/EARLY THIS
EVNG WITH THE ARRIVAL OF MORE ACYC FLOW AND WARMER/DRIER AIR AT
H925. STRONGER WSW FLOW ARND SFC HI IS FCST TO DVLP OVER THE NW HALF
OF THE CWA AFT 06Z...WITH PWAT RISING AS THIS FLOW TAPS MORE MSTR
SHOWN ON THE 12Z BIS RAOB. MOST SUSTAINED CONDITIONS FOR RADIATIONAL
COOLING LOOK TO BE OVER THE SCNTRL AND E...WHERE THE GRADIENT FLOW
WL REMAIN WEAKER/PWAT LOWER AND UNDER 0.5 INCH THRU 12Z WED. OPTED
TO EXTEND GOING FROST ADVY NEAR THE WI BORDER TO INCLUDE MOST OF THE
CWA FROM BARAGA TO THE E...WITH MIN TEMPS CLOSER TO THE LOWER END OF
GUIDANCE IN THESE AREAS PER OBSVD MIXING OF DEWPTS UPSTREAM.
WED...AS SFC HI PRES DRIFTS SLOWLY E ACRS LK HURON...STRONGER SW
FLOW WL DVLP OVER THE ENTIRE CWA. WITH APRCH OF DISTURBANCE NOW
MOVING THRU THE NRN PLAINS AND SOME MSTR RETURN...EXPECT AT LEAST
SOME CLDS TO INVADE MAINLY THE WRN ZNS IN THE AFTN. ALTHOUGH THE GFS
GENERATES SOME PCPN OVER THE FAR W LATE IN THE DAY...PREFER TO
FOLLOW THE DRY 12Z NAM/CNDN/LOCAL WRF-ARW DUE TO VERY DRY NATURE OF
LLVL AIRMASS. MIXING TO H8 ON NAM FCST SDNGS YIELDS HI TEMPS
REBOUNDING TO 70 TO 75 AWAY FM LK MODERATION.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 325 PM EDT TUE JUN 12 2012
THE WEAK HIGH PRESSURE RIDGE IN PLACE FOR WEDNESDAY WILL SLIDE
EASTWARD AS A TROUGH OVER THE CANADIAN PRAIRIE DIGS DOWN INTO THE
NORTHERN PLAINS. MODELS AGREE THAT A SHORTWAVE WILL BE APPROACHING
WESTERN UPPER MICHIGAN BY 00Z THURSDAY...THOUGH THERE SEEMS TO BE
DIFFERENCES WITH HOW STRONG IT WILL BE. THE GEM/ECMWF SEEM TO AGREE
ON A WEAKER SOLUTION...WHILE THE GFS DEVELOPS A SMALL TROUGH. THE
GFS ALSO AMPLIFIES THE EXITING RIDGE MUCH MORE THAN THE OTHER
MODELS. WILL STICK WITH A BLEND MORE SIMILAR TO THE GEM/ECMWF FOR
NOW GIVEN THEIR AGREEMENT...THOUGH CONFIDENCE IS NOT VERY HIGH. THIS
KEEPS MOST OF THE PRECIPITATION THAT WILL OCCUR WITH THIS SHORTWAVE
OVER WESTERN LAKE SUPERIOR AND THE WEST HALF OF THE CWA. WILL KEEP
LOW CHANCE POPS OVER THESE AREAS TO ACCOUNT FOR UNCERTAINTY DURING
THE DAY ON THURSDAY. MODEL SOUNDINGS SUGGEST MIXING TO AROUND
850MB...WHICH PUTS HIGHS IN THE 70S AND PERHAPS LOW 80S. DESPITE
INCOMING CLOUD COVER WITH THE SHORTWAVE...EXPECT THE WARMEST
TEMPERATURES TO BE OUT WEST WITH THE HIGHEST 850MB TEMPS OF AROUND
13C. WITH SKIES MOSTLY SUNNY OUT EAST...EXPECT MIXING TO BRING
RELATIVE HUMIDITY DOWN INTO THE 30 PERCENT RANGE. WITH THE STRONGER
PRESSURE GRADIENT ASSOCIATED WITH THE LOW PRESSURE SYSTEM...EXPECT
GUSTY SOUTHERLY TO SOUTHEASTERLY WINDS ACROSS MUCH OF THE
AREA...MAINLY NORTH CENTRAL AND OVER LAKE SUPERIOR. HIGHEST GUSTS
ARE EXPECTED TO BE AROUND 25 KNOTS.
FRIDAY THE TROUGH WILL SWING JUST NORTH OF LAKE SUPERIOR...REACHING
HUDSON BAY BY 00Z SATURDAY. MODELS SEEM TO BE IN FAIRLY GOOD
AGREEMENT ON THE AMOUNT OF QPF ASSOCIATED WITH THE PASSING FRONT
ACROSS WEST AND CENTRAL UPPER MICHIGAN...WITH AROUND 0.25-0.50 INCH
IMPACTING THE AREA. THE NAM BRINGS THE FRONT ALL THE WAY THROUGH THE
CWA...BRINGING 0.25 INCH TO THE EASTERN AREAS. THE ECMWF/GEM/GFS
TAKE THE BEST UPPER LEVEL FORCING NORTHWARD /PER 850-500MB QVECTOR
CONVERGENCE/ AND THEREFORE KEEP MUCH OF THE EASTERN CWA DRY. THERE
ARE ALSO DIFFERENCES IN TIMING OF PRECIPITATION...SO HAVE LOWERED
CONFIDENCE IN PUTTING SPECIFICS INTO THE FORECAST. KEPT THE BEST
CHANCES OVER LAKE SUPERIOR AND ACROSS THE WEST AND CENTRAL. MU/ML
CAPE VALUES THURSDAY NIGHT INTO FRIDAY AFTERNOON RANGE FROM AROUND
200-1000 J/KG...SO KEPT THUNDER CHANCES IN. WITH PRESSURE GRADIENT
REMAINING TIGHT...WINDS WILL CONTINUE TO GUST INTO THE 20-25 KNOT
RANGE THROUGH FRIDAY EVENING.
FOR THE EXTENDED /THE WEEKEND INTO TUESDAY/...
FOR THE MOST PART...IT SEEMS THROUGH THE WEEKEND A RIDGE WILL CENTER
ITSELF OVER LOWER MICHIGAN...AND SHORTWAVES WILL RIDE AROUND THE
IT BRINGING CHANCES OF PRECIPITATION. FOR THE FIRST PART OF THE
WORK WEEK...A STRONGER LOW PRESSURE TROUGH WILL SWING INTO THE
NORTHERN PLAINS AND BRING ADDITIONAL PRECIPITATION/THUNDERSTORMS TO
MUCH OF THE CWA. HOWEVER...MODELS DIFFER ON TIMING AND PLACEMENT OF
FEATURES. THE GFS/GEM BRING A STRONGER RIDGE UP FROM THE
PLAINS...KEEPING MUCH OF THE PRECIPITATION ASSOCIATED WITH A SECOND
TROUGH/SHORTWAVE CONFINED TO THE WESTERN CWA OR NOT IN THE UPPER
PENINSULA AT ALL. THE GFS EVENTUALLY DEVELOPS THE TROUGH INTO A
CLOSED LOW...AND THEN MOVES THE PRECIPITATION THROUGH ON MONDAY. THE
ECMWF KEEPS THE RIDGE FURTHER SOUTH AND EAST...AND BRINGS A MUCH
MORE POTENT SHORTWAVE INTO UPPER MICHIGAN SATURDAY MORNING INTO
MONDAY. WITH SUCH A VARIANCE IN SOLUTIONS...DO NOT FEEL CONFIDENT
BUMPING UP ANY POPS. WILL KEEP THE MENTION OF THUNDER AS MODELS SEEM
TO BRING IN A DECENT AMOUNT OF INSTABILITY THROUGH THE WEEKEND. AS
FOR HIGH TEMPERATURES...850MB TEMPS LOOK TO BE IN THE 16-18C
RANGE...SO WILL KEEP FORECASTED HIGHS IN THE UPPER 70S TO THE MID
80S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 132 AM EDT WED JUN 13 2012
HIGH PRESSURE TO INFLUENCE THE WEATHER THROUGH THE FORECAST PERIOD
WITH VFR CONDITIONS PREVAILING. WINDS TO STAY LIGHT OVERNIGHT UNTIL
PICKING UP FROM THE SW AFTER SUNRISE AS SFC HIGH SHIFTS EAST. SOME
GUSTS UP TO 20 KTS EXPECTED OVER KIWD WHERE GRADIENT TO BE A BIT
TIGHTER. MID CLOUDS TO INCREASE AND WINDS BACK TO THE SOUTH TO
SOUTHEAST LATE IN THE FORECAST AS AN APPROACHING LOW PRESSURE SYSTEM
MOVES THROUGH THE NORTHERN PLAINS. THIS FEATURE COULD BRING AN
ISOLATED SHOWER OR THUNDERSTORM TO THE KIWD VICINITY AFTER 0Z
THURSDAY.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 325 PM EDT TUE JUN 12 2012
EXPECT NW WINDS UP TO 25-30 KTS INTO THIS EVENING OVER THE E TO
DIMINISH OVERNIGHT WITH THE ARRIVAL OF A HI PRES RIDGE. THESE LIGHT
WINDS WILL PERSIST INTO WED NIGHT AS THE HI REMAINS DOMINANT. THEN A
STRONGER S WIND UP TO 25 KTS WILL IMPACT MAINLY THE NCENTRAL AND E
PART OF THE LAKE ON THU/FRI UNDER A TIGHTER PRES GRADIENT BETWEEN
THE HI DEPARTING TO THE E AND A LO PRES TROF APPROACHING FROM THE W.
THEN LIGHTER WINDS WILL PREVAIL AGAIN THIS COMING WEEKEND WITH A
WEAKER PRES GRADIENT FORECAST TO DOMINATE THE UPPER LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FROST ADVISORY UNTIL 7 AM EDT /6 AM CDT/ THIS MORNING FOR MIZ002-
004>007-009>014-084-085.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...MCB
AVIATION...RJT
MARINE...KC
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
446 AM EDT WED JUN 13 2012
.SYNOPSIS...
COOLER AND DRIER AIR WILL MOVE IN AS HIGH PRESSURE BUILDS OVER
THE GREAT LAKES. DRY CONDITIONS ARE EXPECTED THROUGH THE COMING
WEEKEND. NEAR NORMAL TEMPERATURES THURSDAY AND FRIDAY...WILL EDGE
UPWARD BY EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
430 AM UPDATE...
COLD FRONT...WHICH WAS WELL MARKED BY BAND OF LIGHT
SHOWERS...JUST PASSED THROUGH MONTICELLO AND IS CLEARING THE AREA.
HOWEVER...NAM AND RUC ARE IN AGREEMENT WITH UPSTREAM SATELLITE
IMAGERY...THAT A TEMPORARY SCT TO BKN STRATOCUMULUS DECK WILL MOVE
BACK IN AS FINAL VORTICITY LOBE CARRIES THROUGH FROM 11Z NW TO 15Z
SE. THESE CLOUDS WILL THEN MIX OUT WITH THE MUCH DRIER AIR MASS
ADVECTING IN...ALONG WITH HIGH PRESSURE BUILDING IN FROM WESTERN
GREAT LAKES REGION. HIGH TEMPERATURES IN THE WAKE OF THE COLD
FRONT WILL BE SLIGHTLY BELOW NORMAL...AND A FRESH NORTHERLY
BREEZE WITH GUSTS OF 15 TO 25 MPH WILL HELP TO MAKE THE COOLER AIR
MASS MORE APPARENT.
MAINLY CLEAR NIGHT TONIGHT...THOUGH SOME UNCERTAINTY AS TO WHETHER
AT LEAST A FEW CLOUDS WILL TRY TO HANG ON NEAR POCONOS-
CATSKILLS...WHERE WEAK LOW LEVEL CONVERGENCE WILL COINCIDE WITH
SOME MOISTURE AROUND 850MB. EITHER WAY...LOOKING AT A COOL NIGHT
WITH LOWS IN THE MID 40S TO LOW 50S FOR MOST OF THE AREA...THANKS
TO LOW DEWPOINTS AND RADIATIONAL COOLING...WITH A FEW OF THE
TYPICAL COLDER SPOTS EVEN GETTING INTO LOWER 40S. ALSO APPEARS TO
BE A GOOD SET UP FOR PATCHY FOG IN SOME RIVER VALLEYS SUCH AS IN
THE ELMIRA AREA.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
A SLOW UL RIDGING PROCESS WILL BEGIN THIS PERIOD, WITH A STRONG
SURFACE HIGH SETTING UP ALONG THE EASTERN SEABOARD. THIS WILL LEAD
TO A QUIET WEATHER PATTERN, WITH DAYTIME HIGHS PUSHING INTO THE
MIDDLE OR UPPER 70S. OVERNIGHT LOWS WILL DIP INTO THE UPPER 40S
AND LOWER 50S.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
UL RIDGING WILL CONTINUE, LEADING TO A WARMING TREND. THE WEEKEND
WILL BEGIN WITH TEMPERATURES REACHING INTO THE UPPER 70S AND LOWER
80S DURING THE AFTERNOON. BY EARLY NEXT WEEK, THE BUILDING
THICKNESS PATTERN WILL PUSH AFTERNOON MAXES INTO THE LOWER AND
MIDDLE 80S.
THE PATTERN APPEARS DRY, THOUGH WE DO ACCOUNT FOR SOME UNCERTAINTY
WITH SLIGHT CHANCE POPS AT THE END OF THE PERIOD WHEN DEW POINTS
CLIMB BACK TOWARD 60F.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
09Z UPDATE...
FRONT HAS MOVED EAST OF THE AREA AS OF 09Z. LOOKING AT MAINLY VFR
BEHIND THE FRONT AREAWIDE...AT LEAST INITIALLY. A FINAL WEAK UPPER
DISTURBANCE BEHIND THE FRONT...AS CAN NOW BE SEEN BY STRATOCUMULUS
UPSTREAM OVER ONTARIO...WILL ALLOW MVFR OR LOW END VFR DECK TO
DEVELOP FOR MOST TERMINALS DURING THE 11Z-15Z WINDOW /SEE TAFS FOR
TIMING DETAILS/. BECAUSE OF DRYNESS OF INCOMING AIR MASS...NOT
EXPECTING IFR DESPITE A COUPLE HILLTOP MODEL SOUNDINGS SUGGESTING
IT DURING THAT TIME. AFTER THE EARLY MORNING MVFR...STRATOCUMULUS
LIFTS AND MIXES OUT COURTESY OF VERY DRY AIR MASS. NORTHERLY WINDS
GUSTING 15-20 KTS DURING THE DAY WITH VFR...THEN DROPPING TO LESS
THAN 10 KTS WITH DECOUPLING THIS EVENING.
OUTLOOK...
LATE WED NIGHT TO SUNDAY...MAINLY VFR. POSSIBLY EARLY MORNING
IFR/MVFR VALLEY FOG...MAINLY KELM.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP
SHORT TERM...DJP
LONG TERM...DJP
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
241 AM EDT WED JUN 13 2012
.SYNOPSIS...
IN THE WAKE OF AN OVERNIGHT COLD FRONT...COOLER AND DRIER AIR WILL
MOVE IN AS HIGH PRESSURE BUILDS OVER THE GREAT LAKES. MORNING
CLOUDS WILL BREAK UP DURING THE DAY...FOLLOWED BY A COOL NIGHT.
DRY CONDITIONS ARE EXPECTED THROUGH THE COMING WEEKEND...WITH INITIALLY
NEAR NORMAL TEMPERATURES EDGING UPWARD BY EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
2 AM UPDATE...
COLD FRONT...WELL MARKED BY BAND OF LIGHT SHOWERS...STRETCHES FROM
ONEONTA THROUGH WALTON THROUGH SCRANTON AND WILKES-BARRE JUST
BEFORE 2 AM. IT WILL FINISH CLEARING THE AREA BEFORE DAWN.
HOWEVER...NAM AND RUC ARE IN AGREEMENT WITH UPSTREAM
OBSERVATIONS...THAT A TEMPORARY STRATOCUMULUS DECK WILL MOVE BACK
IN AS FINAL VORTICITY LOBE CARRIES THROUGH FROM 10Z NW TO 15Z SE.
THESE CLOUDS WILL THEN MIX OUT WITH THE MUCH DRIER AIR MASS
ADVECTING IN...ALONG WITH HIGH PRESSURE BUILDING IN FROM WESTERN
GREAT LAKES REGION.
MAINLY CLEAR NIGHT TONIGHT...THOUGH SOME UNCERTAINTY AS TO WHETHER
AT LEAST A FEW CLOUDS WILL TRY TO HANG ON NEAR POCONOS-
CATSKILLS...WHERE WEAK LOW LEVEL CONVERGENCE WILL COINCIDE WITH
SOME MOISTURE AROUND 850MB. EITHER WAY...LOOKING AT A COOL NIGHT
WITH LOWS IN THE MID 40S TO LOW 50S FOR MOST OF THE AREA...THANKS
TO LOW DEWPOINTS AND RADIATIONAL COOLING...AND LIGHT NORTHEAST
FLOW.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
A SLOW UL RIDGING PROCESS WILL BEGIN THIS PERIOD, WITH A STRONG
SURFACE HIGH SETTING UP ALONG THE EASTERN SEABOARD. THIS WILL LEAD
TO A QUIET WEATHER PATTERN, WITH DAYTIME HIGHS PUSHING INTO THE
MIDDLE OR UPPER 70S. OVERNIGHT LOWS WILL DIP INTO THE UPPER 40S
AND LOWER 50S.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
UL RIDGING WILL CONTINUE, LEADING TO A WARMING TREND. THE WEEKEND
WILL BEGIN WITH TEMPERATURES REACHING INTO THE UPPER 70S AND LOWER
80S DURING THE AFTERNOON. BY EARLY NEXT WEEK, THE BUILDING
THICKNESS PATTERN WILL PUSH AFTERNOON MAXES INTO THE LOWER AND
MIDDLE 80S.
THE PATTERN APPEARS DRY, THOUGH WE DO ACCOUNT FOR SOME UNCERTAINTY
WITH SLIGHT CHANCE POPS AT THE END OF THE PERIOD WHEN DEW POINTS
CLIMB BACK TOWARD 60F.
&&
.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
06Z UPDATE...
FRONT MOVING INTO KAVP AT 06Z...AFTER HAVING CLEARED THE REMAINDER
OF THE AREA BETWEEN 00Z-06Z. MODELS CONTINUE TO UNDERESTIMATE
DRYNESS OF AIRMASS BEHIND THE FRONT...WITH GUIDANCE AND LAMP
PROBABILITIES SUGGESTING MVFR OR EVEN IFR FOR MOST SITES THROUGH
REMAINDER OF THE NIGHT. INSTEAD...OTHER THAN POSSIBLE BRIEF IFR
CIG/VIS WITH NARROW SHOWER BAND IMMEDIATELY ALONG FRONT FOR
KAVP 06Z-07Z...LOOKING AT MAINLY VFR BEHIND THE FRONT AREAWIDE...AT
LEAST INITIALLY. A FINAL WEAK UPPER DISTURBANCE BEHIND THE
FRONT...AS CAN NOW BE SEEN BY STRATOCUMULUS UPSTREAM OVER
ONTARIO...WILL ALLOW MVFR DECK TO DEVELOP FOR MOST TERMINALS
DURING THE 10Z-14Z WINDOW /SEE TAFS FOR TIMING DETAILS/. BECAUSE
OF DRYNESS OF INCOMING AIR MASS...NOT EXPECTING IFR DESPITE A COUPLE
HILLTOP MODEL SOUNDINGS SUGGESTING IT DURING THAT TIME. AFTER THE
EARLY MORNING MVFR...STRATOCUMULUS LIFTS AND MIXES OUT COURTESY OF
VERY DRY AIR MASS. NORTHERLY WINDS GUSTING 15-20 KTS DURING THE
DAY WITH VFR...THEN DROPPING TO LESS THAN 10 KTS WITH DECOUPLING
THIS EVENING.
OUTLOOK...
LATE WED NIGHT TO SUNDAY...MAINLY VFR. POSSIBLY EARLY MORNING
IFR/MVFR VALLEY FOG AT KELM.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP
SHORT TERM...DJP
LONG TERM...DJP
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
204 AM EDT WED JUN 13 2012
.SYNOPSIS...
IN THE WAKE OF AN OVERNIGHT COLD FRONT...COOLER AND DRIER AIR WILL
MOVE IN AS HIGH PRESSURE BUILDS OVER THE GREAT LAKES. MORNING
CLOUDS WILL BREAK UP DURING THE DAY...FOLLOWED BY A COOL NIGHT.
DRY CONDITIONS ARE EXPECTED THROUGH THE COMING WEEKEND...WITH INITIALLY
NEAR NORMAL TEMPERATURES EDGING UPWARD BY EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
2 AM UPDATE...
COLD FRONT...WELL MARKED BY BAND OF LIGHT SHOWERS...STRETCHES FROM
ONEONTA THROUGH WALTON THROUGH SCRANTON AND WILKES-BARRE JUST
BEFORE 2 AM. IT WILL FINISH CLEARING THE AREA BEFORE DAWN.
HOWEVER...NAM AND RUC ARE IN AGREEMENT WITH UPSTREAM
OBSERVATIONS...THAT A TEMPORARY STRATOCUMULUS DECK WILL MOVE BACK
IN AS FINAL VORTICITY LOBE CARRIES THROUGH FROM 10Z NW TO 15Z SE.
THESE CLOUDS WILL THEN MIX OUT WITH THE MUCH DRIER AIR MASS
ADVECTING IN...ALONG WITH HIGH PRESSURE BUILDING IN FROM WESTERN
GREAT LAKES REGION.
MAINLY CLEAR NIGHT TONIGHT...THOUGH SOME UNCERTAINTY AS TO WHETHER
AT LEAST A FEW CLOUDS WILL TRY TO HANG ON NEAR POCONOS-
CATSKILLS...WHERE WEAK LOW LEVEL CONVERGENCE WILL COINCIDE WITH
SOME MOISTURE AROUND 850MB. EITHER WAY...LOOKING AT A COOL NIGHT
WITH LOWS IN THE MID 40S TO LOW 50S FOR MOST OF THE AREA...THANKS
TO LOW DEWPOINTS AND RADIATIONAL COOLING...AND LIGHT NORTHEAST
FLOW.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
A VERY QUIET PERIOD SHAPING UP FOR THE CONCLUSION OF THE WORK
WEEK AS HIGH PRESSURE BECOMES FIRMLY ESTABLISHED ACROSS THE FCST
AREA. EXPECT TEMPS TO GRADUALLY MAKE A REBOUND BACK INTO THE
MIDDLE TO UPPER 70S AS EARLY AS THU AFTERNOON WITH A GRADUAL
WARMING TREND THEN ANTICIPATED THROUGH THE UPCOMING WEEKEND AS
HIGH PRESSURE SLIDES NORTHEAST OF THE AREA.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
2 PM UPDATE...
VERY QUIET EXTENDED WITH A LARGE SURFACE HIGH ACROSS THE ENTIRE
EAST COAST OF THE UNITED STATES THROUGH THE WEEKEND INTO AT LEAST
MONDAY AND MAYBE TUESDAY OR WEDNESDAY. A SOUTHWEST FLOW OF
MOISTER AIR COULD CAUSE A FEW SHOWERS OR THUNDERSTORMS ON TUESDAY.
AS USUAL THAT FAR OUT DIFFERENCES BETWEEN THE MODELS ON TIMING AND
STRENGTH. BOTH THE GFS AND ECMWF HAVE A LARGE UPPER LEVEL TROF
MOVING INTO THE PLAINS WHILE A STORM IS OFF THE SE US COAST.
LONG TERM TEMPERATURES START OUT WITH NEAR NORMAL TEMPERATURES
AROUND 80 THAT RISE INTO THE MID TO UPPER 80S NEXT WEEK. DEWPOINT
TEMPS SHOULD BE MOSTLY IN THE 50S. EARLY MORNING VALLEY FOG
POSSIBLE EACH DAY.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
06Z UPDATE...
FRONT MOVING INTO KAVP AT 06Z...AFTER HAVING CLEARED THE REMAINDER
OF THE AREA BETWEEN 00Z-06Z. MODELS CONTINUE TO UNDERESTIMATE
DRYNESS OF AIRMASS BEHIND THE FRONT...WITH GUIDANCE AND LAMP
PROBABILITIES SUGGESTING MVFR OR EVEN IFR FOR MOST SITES THROUGH
REMAINDER OF THE NIGHT. INSTEAD...OTHER THAN POSSIBLE BRIEF IFR
CIG/VIS WITH NARROW SHOWER BAND IMMEDIATELY ALONG FRONT FOR
KAVP 06Z-07Z...LOOKING AT MAINLY VFR BEHIND THE FRONT AREAWIDE...AT
LEAST INITIALLY. A FINAL WEAK UPPER DISTURBANCE BEHIND THE
FRONT...AS CAN NOW BE SEEN BY STRATOCUMULUS UPSTREAM OVER
ONTARIO...WILL ALLOW MVFR DECK TO DEVELOP FOR MOST TERMINALS
DURING THE 10Z-14Z WINDOW /SEE TAFS FOR TIMING DETAILS/. BECAUSE
OF DRYNESS OF INCOMING AIR MASS...NOT EXPECTING IFR DESPITE A COUPLE
HILLTOP MODEL SOUNDINGS SUGGESTING IT DURING THAT TIME. AFTER THE
EARLY MORNING MVFR...STRATOCUMULUS LIFTS AND MIXES OUT COURTESY OF
VERY DRY AIR MASS. NORTHERLY WINDS GUSTING 15-20 KTS DURING THE
DAY WITH VFR...THEN DROPPING TO LESS THAN 10 KTS WITH DECOUPLING
THIS EVENING.
OUTLOOK...
LATE WED NIGHT TO SUNDAY...MAINLY VFR. POSSIBLY EARLY MORNING
IFR/MVFR VALLEY FOG AT KELM.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP
SHORT TERM...CMG
LONG TERM...TAC
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
254 AM EDT WED JUN 13 2012
.SYNOPSIS...
A COLD FRONT WILL MOVE SLOWLY ACROSS THE AREA TODAY BRINGING WITH
IT MORE RAIN. HIGH PRESSURE WILL BUILD IN THURSDAY AND MAINTAIN A
RELATIVELY COOL AND DRY PATTERN THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1005 PM TUESDAY...DECENT CLUSTER OF SHOWERS AND THUNDERSTORMS
EXTENDS ACROSS THE SE NC COASTAL COUNTIES AND THE ADJACENT COASTAL
AND OFFSHORE WATERS. MOVEMENT IS TO THE ENE NEAR 15 MPH. VIA LATEST
KLTX RAINFALL ESTIMATES...LOOK FOR AN ADDITIONAL ONE TENTH TO ONE
QUARTER OF AN INCH...EXCEPT ONE HALF TO 1 INCH FROM ANY OF THE
STRONGER SHOWERS AND STORMS. THIS CLUSTER/AREA SHOULD TRACK NE OF
THE AREA BY MIDNIGHT TO 1 AM.
THE DEEP PLUME OF MOISTURE FROM THE TROPICS IS SLOWLY BEING CUT OFF
AS THE MID-UPPER LEVEL TROF REACHES THE EASTERN CAROLINAS...VIA THE
LATEST NEAR TERM RUC MODEL HOURLY RUNS. AS A RESULT...THE BEST
CHANCES FOR PCPN AND THE ORIENTATION OF OVERNIGHT POPS ACROSS THE
ILM CWA...WILL CONTINUE TO BE GEARED ALONG THE COASTAL COUNTIES AND
ADJACENT COASTAL/OFFSHORE WATERS. THE 5H VORT ACROSS SOUTHERN GA IS
PROGGED TO TRACK OFF THE GA COAST LATE THIS EVENING AND OVERNIGHT
AND SHOULD NOT BE A PROBLEM FOR THE ILM CWA. WILL HAVE TO MAINLY
DEAL WITH THE APPROACH OF FRONTAL DYNAMICS AND ANY SHEARED MID LEVEL
VORTS ACCOMPANYING IT FOR THE CONTINUED POPS OVERNIGHT. TWEAKED MIN
TEMPS UPWARDS BY A DEGREE OR 2 BASED ON LATEST TRENDS AND A PEAK
LOOK AT THE NEW 00Z GUIDANCE.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3:00 AM WEDNESDAY...MAIN FORECAST CHALLENGE FOR THE SHORT TERM WILL
BE TEMPERATURES AS MOISTURE WILL BE ON THE DECREASE AS AN OMEGA
CONFIGURATION DEVELOPS AT THE MID LEVELS. AT THE SURFACE A
FORMIDABLE NORTHEAST FLOW WILL DEVELOP AS HIGH PRESSURE BUILDS
DOWN FROM THE NORTHEAST AND LOW PRESSURE MEANDERS NEAR BERMUDA.
MET GUIDANCE IS QUITE A BIT WARMER AS OPPOSED TO THE MAV NUMBERS
THROUGH THE PERIOD MORE-SO THURSDAY. THIS APPEARS TO BE A FUNCTION
OF LINGERING LOW LEVEL MOISTURE VIA THE GFS. NUMBERS JOG TOWARD
SLIGHTLY BETTER AGREEMENT FRIDAY. HAVE LEANED TOWARD THE COOLER
MAV NUMBERS OPTING FOR A SLOWER PROGRESSION OF THE LOW LEVEL
MOISTURE. NO POPS THROUGH THE PERIOD.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 3:00 AM WEDNESDAY...NO SIGNIFICANT CHANGES TO THE MEDIUM RANGE
GUIDANCE THIS MORNING AS THE FORECAST AREA CONTINUES TO BE
SITUATED IN THE EASTERN PART OF A MID LEVEL OMEGA PATTERN FOR MOST
OF THE PERIOD. I DID INCREASE THE POPS INCREMENTALLY SUNDAY AND
MONDAY TO SLIGHT CHANCE TO MATCH HPC AND ADJACENT OFFICES VIA
NORTHEAST RESULTANT SEA BREEZE COMBINED WITH THE 700MB SUBSIDENCE
INVERSION ABATING. THE PATTERN BEGINS TO CHANGE LATE IN THE PERIOD
WITH THE GFS ADVERTISING A REX BLOCK DEVELOPING SO CONFIDENCE IS
BELOW AVERAGE. NO CHANGES TO TEMPERATURE FORECAST.
&&
.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
AS OF 06Z...A VARIETY OF CLOUD DECKS EXPECTED OVERNIGHT FROM
UPSTREAM CONVECTIVE DEBRIS TO AREAS OF STRATUS AND STRATO-CUMULUS.
AS A RESULT...CIGS AND VSBYS WILL VARY FROM IFR TO VFR THROUGH
AROUND SUNRISE. IFR/MVFR CIGS AND VSBYS WILL IMPROVE ALL AREAS
OUTSIDE OF CONVECTION THEREAFTER. WILL ALSO INCLUDE TEMPO SHOWERS AT
KLBT 08-10Z AS UPSTREAM CONVECTION CONTINUES TO WEAKEN AS IT MOVES
TO THE SOUTH. CONVECTION IS EXPECTED TO BECOME SCATTERED ONCE
DAYTIME HEATING PEAKS IN THE AFTERNOON. WINDS WILL BE LIGHT AND
VARIABLE NEAR THE FRONTAL BOUNDARY...BUT FOR THE MYRTLES...THE SEA
BREEZE WILL LIKELY DOMINATE IN THE AFTERNOON ALLOWING WINDS TO TURN
ONSHORE.
EXTENDED OUTLOOK...VFR THROUGH THE FORECAST PERIOD.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1005 PM TUESDAY...SCEC WILL BE ALLOWED TO EXPIRE AT MIDNIGHT
FOR THE ILM NC WATERS. UNTIL THE COLD FRONT REACHES THE COASTAL
WATERS WHICH WILL LIKELY BE CLOSER TO DAYBREAK WED...THE SFC PG AND
PATTERN AHEAD OF IT WILL YIELD SW WINDS AROUND 15 KT...OCCASIONALLY
UP TO 20 KT FOR THE LOCAL WATERS OFF CAPE FEAR. AS THE FRONT MOVES
CLOSER WINDS WILL VEER TO THE WSW TOWARD DAYBREAK AND DROP TO 10 TO
15 KT. SIGNIFICANT SEAS WILL RUN 3 TO 4 FT...UP TO 5 FT ACROSS
THE LOCAL WATERS OFF CAPE FEAR THROUGH MIDNIGHT. DOMINANT PERIODS
WILL BE AROUND 6 SECONDS. WIND DRIVEN WAVES WILL DOMINATE SIG SEAS
WITH A CONTINUED UNDERLYING 1 TO 1.5 FT ESE 9-10 SECOND PERIOD
GROUND SWELL.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3:00 AM WEDNESDAY...A NORTHEASTERLY FLOW WILL PREVAIL THROUGHOUT
THE PERIOD AS HIGH PRESSURE BUILDS DOWN FROM THE NORTHEAST AND LOW
PRESSURE SLOWLY DEVELOPS WELL INTO THE ATLANTIC. STRONGEST WINDS
OCCUR LATE FRIDAY WHEN THE 20-25 KNOT RANGE WILL LIKELY BE CLOSER TO
THE HIGH END OF THE RANGE. THE PERSISTENT FETCH WILL ALLOW SEAS TO
BUILD LATE THURSDAY TO ECLIPSE THE SIX FOOT SMALL CRAFT CRITERIA AND
CONTINUE THROUGH THE REMAINDER OF THE PERIOD.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3:00 AM WEDNESDAY...ESSENTIALLY NO CHANGES TO THE EXTENDED COASTAL
WATERS FORECAST AS A NORTHEASTERLY FLOW SHOULD PREVAIL. MAY SEE MORE
VEERING SUNDAY AFTERNOON AS THE FLOW IS LIGHTER ALLOWING MORE OF A
NORTHEAST RESULTANT TO DEVELOP. THE CAVEAT WITH THIS TYPE OF
SCENARIO ARE THE EMBEDDED SURGES. I DID WALK BACK SEAS SLIGHTLY BUT
A SMALL CRAFT ADVISORY MAY STILL BE NEEDED BUT IT APPEARS MORE
MARGINAL AT THIS POINT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SHK
NEAR TERM...MBB
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...RJD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
144 AM EDT WED JUN 13 2012
.SYNOPSIS...
A COLD FRONT WILL MOVE SOUTHEAST AND ACROSS THE EASTERN CAROLINAS
WEDNESDAY...MOVING OFFSHORE WEDNESDAY NIGHT. SHOWERS AND
THUNDERSTORMS WILL END AS THE FRONT MOVES OFFSHORE. LOW PRESSURE
SHOULD DEVELOP ALONG THE FRONT THURSDAY...BRINGING NORTHEAST WINDS
AND MILD TEMPERATURES TO THE CAROLINAS THURSDAY INTO SATURDAY. HIGH
PRESSURE WILL BUILD INTO THE AREA FROM THE NORTHEAST EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1005 PM TUESDAY...DECENT CLUSTER OF SHOWERS AND THUNDERSTORMS
EXTENDS ACROSS THE SE NC COASTAL COUNTIES AND THE ADJACENT COASTAL
AND OFFSHORE WATERS. MOVEMENT IS TO THE ENE NEAR 15 MPH. VIA LATEST
KLTX RAINFALL ESTIMATES...LOOK FOR AN ADDITIONAL ONE TENTH TO ONE
QUARTER OF AN INCH...EXCEPT ONE HALF TO 1 INCH FROM ANY OF THE
STRONGER SHOWERS AND STORMS. THIS CLUSTER/AREA SHOULD TRACK NE OF
THE AREA BY MIDNIGHT TO 1 AM.
THE DEEP PLUME OF MOISTURE FROM THE TROPICS IS SLOWLY BEING CUT OFF
AS THE MID-UPPER LEVEL TROF REACHES THE EASTERN CAROLINAS...VIA THE
LATEST NEAR TERM RUC MODEL HOURLY RUNS. AS A RESULT...THE BEST
CHANCES FOR PCPN AND THE ORIENTATION OF OVERNIGHT POPS ACROSS THE
ILM CWA...WILL CONTINUE TO BE GEARED ALONG THE COASTAL COUNTIES AND
ADJACENT COASTAL/OFFSHORE WATERS. THE 5H VORT ACROSS SOUTHERN GA IS
PROGGED TO TRACK OFF THE GA COAST LATE THIS EVENING AND OVERNIGHT
AND SHOULD NOT BE A PROBLEM FOR THE ILM CWA. WILL HAVE TO MAINLY
DEAL WITH THE APPROACH OF FRONTAL DYNAMICS AND ANY SHEARED MID LEVEL
VORTS ACCOMPANYING IT FOR THE CONTINUED POPS OVERNIGHT. TWEAKED MIN
TEMPS UPWARDS BY A DEGREE OR 2 BASED ON LATEST TRENDS AND A PEAK
LOOK AT THE NEW 00Z GUIDANCE.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 PM TUESDAY...THE BAND OF DEEP TROPICAL MOISTURE WILL
BEGIN TO NUDGE OFFSHORE WEDNESDAY AS THE 500 MB UPPER TROUGH
BEGINS TO KICK EAST AND FINALLY OFF THE COAST WEDNESDAY NIGHT.
THE SURFACE COLD FRONT WILL ACCOMPANY THE UPPER TROUGH TO THE COAST
WEDNESDAY AFTERNOON...BUT A WEAK SEABREEZE WILL HOLD UP THE
FRONT`S EASTWARD PROGRESS UNTIL EVENING. THE HIGHEST CHANCES FOR
SHOWERS AND STORMS WEDNESDAY WILL OCCUR NEAR THE COAST WHERE
ENHANCED LOW-LEVEL CONVERGENCE WILL COEXIST WITH THE LINGERING
TROPICAL HIGH-PRECIPITABLE WATER ATMOSPHERE. CONVECTIVE COVERAGE
SHOULD RANGE FROM 50-60 PERCENT ALONG THE COAST TO ONLY 20-30 PERCENT
ALONG AND WEST OF INTERSTATE 95. UNLIKE TODAY...WEDNESDAY`S STORM
MOTION SHOULD BE FROM NORTH TO SOUTH AS THE MID-LEVEL FLOW SHIFTS
BEFORE THE SURFACE FRONT ARRIVES.
DRIER AIR SHOULD OVERSPREAD THE REGION FROM NW TO SE WEDNESDAY
NIGHT WITH MODEL PRECIP WATER VALUES DROPPING FROM ~2.0 INCHES TO
BARELY 0.6 INCHES BY 12Z THURSDAY. MULTIPLE AREAS OF LOW PRESSURE
WILL DEVELOP ALONG THE FRONT WELL OFFSHORE THURSDAY AND THURSDAY
NIGHT. THE MAIN IMPACTS TO LAND WILL BE INCREASING NORTH TO
NORTHEAST WINDS AND ENOUGH COLD ADVECTION TO KEEP TEMPERATURES AND
DEWPOINTS SURPRISINGLY MILD FOR MID-JUNE. ENOUGH ATLANTIC MOISTURE
SHOULD GET ADVECTED BACK ONSHORE LATE THURSDAY AFTERNOON INTO
THURSDAY NIGHT TO SPREAD A BATCH OF LOW CLOUDS INLAND ALONG THE
COAST WITH THE LARGEST IMPACTS EXPECTED AROUND WILMINGTON.
MOS TEMPERATURES LOOK PRETTY GOOD THROUGH THE PERIOD WITH LITTLE
SPREAD SEEN BETWEEN NUMBERS FROM THE GFS...NAM...OR THE
EXPERIMENTAL ECMWF MOS.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 3 PM TUESDAY...SYNOPTIC PATTERN WILL BE CHARACTERIZED BY A
MID-LEVEL RIDGE AXIS EXTENDING FROM THE GREAT LAKES SOUTHWESTWARD TO
THE SOUTHERN PLAINS...AND A MID-LEVEL TROUGH AXIS A FEW HUNDRED
MILES OFF THE CAROLINA COAST. AT THE SURFACE...THIS WILL TRANSLATE
INTO WEDGE SCENARIO AS HIGH PRESSURE EXTENDS SOUTHWARD ALONG THE
EASTERN SIDE OF THE APPALACHIANS...WITH NORTHEASTERLY FLOW KEEPING
TEMPERATURES ON THE COOL SIDE OF CLIMATOLOGY. MODELS SUGGEST THIS
PATTERN WILL PERSIST THROUGH THE EXTENDED PERIOD.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 06Z...A VARIETY OF CLOUD DECKS EXPECTED OVERNIGHT FROM
UPSTREAM CONVECTIVE DEBRIS TO AREAS OF STRATUS AND STRATO-CUMULUS.
AS A RESULT...CIGS AND VSBYS WILL VARY FROM IFR TO VFR THROUGH
AROUND SUNRISE. IFR/MVFR CIGS AND VSBYS WILL IMPROVE ALL AREAS
OUTSIDE OF CONVECTION THEREAFTER. WILL ALSO INCLUDE TEMPO SHOWERS AT
KLBT 08-10Z AS UPSTREAM CONVECTION CONTINUES TO WEAKEN AS IT MOVES
TO THE SOUTH. CONVECTION IS EXPECTED TO BECOME SCATTERED ONCE
DAYTIME HEATING PEAKS IN THE AFTERNOON. WINDS WILL BE LIGHT AND
VARIABLE NEAR THE FRONTAL BOUNDARY...BUT FOR THE MYRTLES...THE SEA
BREEZE WILL LIKELY DOMINATE IN THE AFTERNOON ALLOWING WINDS TO TURN
ONSHORE.
EXTENDED OUTLOOK...VFR THROUGH THE FORECAST PERIOD.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1005 PM TUESDAY...SCEC WILL BE ALLOWED TO EXPIRE AT MIDNIGHT
FOR THE ILM NC WATERS. UNTIL THE COLD FRONT REACHES THE COASTAL
WATERS WHICH WILL LIKELY BE CLOSER TO DAYBREAK WED...THE SFC PG AND
PATTERN AHEAD OF IT WILL YIELD SW WINDS AROUND 15 KT...OCCASIONALLY
UP TO 20 KT FOR THE LOCAL WATERS OFF CAPE FEAR. AS THE FRONT MOVES
CLOSER WINDS WILL VEER TO THE WSW TOWARD DAYBREAK AND DROP TO 10 TO
15 KT. SIGNIFICANT SEAS WILL RUN 3 TO 4 FT...UP TO 5 FT ACROSS
THE LOCAL WATERS OFF CAPE FEAR THROUGH MIDNIGHT. DOMINANT PERIODS
WILL BE AROUND 6 SECONDS. WIND DRIVEN WAVES WILL DOMINATE SIG SEAS
WITH A CONTINUED UNDERLYING 1 TO 1.5 FT ESE 9-10 SECOND PERIOD
GROUND SWELL.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 PM TUESDAY...A SURFACE COLD FRONT WILL MAKE ITS WAY DOWN
TO THE COAST MORNING WEDNESDAY...BUT IT SHOULD STALL NEAR THE
BEACHES DURING THE AFTERNOON AS A WEAK SEABREEZE HOLDS UP THE
FRONT`S PROGRESS EAST. SCATTERED SHOWERS AND STORMS WILL ACCOMPANY
THE SLOW-MOVING FRONT WEDNESDAY. THE FRONT WILL RESUME ITS
OFFSHORE MOVEMENT DURING THE EVENING AND SHOULD MOVE WELL OFFSHORE
WEDNESDAY NIGHT. THE 12Z NAM HAS COME INTO AGREEMENT WITH
YESTERDAY`S GFS (AND TODAY`S GFS AS WELL) SHOWING THE DEVELOPMENT
OF MULTIPLE CENTERS OF LOW PRESSURE OFFSHORE THURSDAY ALONG THE
FRONT. THE EXACT LOCATION OF THESE LOWS ARE NOT AS IMPORTANT AS THE
OVERALL IMPACT ON TIGHTENING OUR LOCAL PRESSURE GRADIENT THURSDAY
AFTERNOON INTO THURSDAY NIGHT WITH A SUBSTANTIAL INCREASE IN WIND
SPEEDS EXPECTED ALONG THE COAST. OUR LATEST FORECAST INCREASES WINDS
INTO THE 20-25 KT RANGE THURSDAY NIGHT WITH THE POTENTIAL FOR GUSTS
APPROACHING 30 KT LATE. THIS WILL BUILD SEAS FROM A GENTLE 2-3 FT
WEDNESDAY...TO AS HIGH AS 6-8 FEET NORTH AND EAST OF CAPE FEAR LATE
THURSDAY NIGHT.
LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 3 PM TUESDAY...PERSISTENT NORTHEAST FLOW IS EXPECTED OVER
THE WATERS AS SURFACE HIGH PRESSURE EXTENDS SOUTHWARD ACROSS THE
INLAND CAROLINAS...AND A TROUGH LINGERS WELL OFFSHORE. A MODERATE
PRESSURE GRADIENT ACROSS THE WATERS WILL LIKELY KEEP WINDS IN A
15-25 KT RANGE...AND A PERSISTENT FETCH SHOULD ALLOW SEAS TO BUILD
AS HIGH AS 5-7 FT IN THE 10-20 NM RANGE. SMALL CRAFT ADVISORY
THRESHOLDS WILL BE APPROACHED...IF NOT EXCEEDED AT TIMES FRIDAY AND
SATURDAY...ESPECIALLY ACROSS THE NORTH CAROLINA COASTAL WATERS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...DCH
SHORT TERM...TRA
LONG TERM...CRM
AVIATION...SRP/RJD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
429 AM CDT WED JUN 13 2012
.SHORT TERM...NOW THROUGH THURSDAY AFTERNOON...
THE MAIN PROBLEM OF THE DAY IS CONCERNED WITH THE POTENTIAL FOR
SEVERE WEATHER LATER TODAY. THE DAY 1 STORM PREDICTION CENTER
DISCUSSION REFERENCES THUNDERSTORMS FORMING ALONG A SURFACE COLD
FRONT PUSHING INTO THE WESTERN DAKOTAS THIS AFTERNOON...BUT
DOWNPLAYS DAYTIME SEVERE POTENTIAL DUE TO LIMITED INSTABILITY.
THE 00/06 UTC NAM DEPICTS A LINE OF STRONGER THUNDERSTORMS
FORMING...OR STRENGTHENING OF ONGOING CONVECTION...ALONG A LINE
FROM MOBRIDGE SOUTH DAKOTA TO VALLEY CITY NORTH DAKOTA BETWEEN 06
AND 09 UTC THURSDAY MORNING. GREATER INSTABILITY IN THIS REGION
AND FAVORABLE LOW-LEVEL JET SUPPORT SUGGEST THAT STORMS ARE MORE
LIKELY TO BECOME SEVERE THEN...WHICH AGREES WITH THE STORM
PREDICTION CENTER SLIGHT RISK AREA.
THE 06 UTC HRRR DOES INITIATE AT LEAST MODERATE CONVECTION ON THE
MISSOURI SLOPE AT 19 UTC TODAY...BUT IT HAS DIFFICULTY SUSTAINING
IT...WHICH IS CONSISTENT WITH LESS THAN FAVORABLE INSTABILITY
PARAMETERS.
OTHERWISE...GUSTY POST FRONTAL WESTERLIES MAY APPROACH LOWER WIND
ADVISORY CRITERIA THURSDAY AFTERNOON.
.LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...
A BREAK IN THUNDERSTORM ACTIVITY FOR NORTH DAKOTA THURSDAY NIGHT AS
ONE SHORTWAVE EXITS THE AREA AND THE NEXT DISTURBANCE MOVES ACROSS
THE ROCKIES.
AN ACTIVE WEATHER PATTERN CONTINUES THROUGH THE REST OF THE LONG
TERM PERIOD. MODELS IN FAIRLY GOOD AGREEMENT FRIDAY AND SATURDAY
WITH SEVERAL SHORTWAVES MOVING THROUGH THE STATE WITH A PROGRESSIVE
SERIES OF DISTURBANCES. BY SUNDAY THE OVERALL SYNOPTIC WEATHER
PATTERN IS DOMINATED BY A RELATIVELY PERSISTENT BROAD UPPER LEVEL
LOW OVER CENTRAL CANADA...WHICH ALSO BRINGS SEVERAL UPPER LEVEL
SHORTWAVES MOVING ACROSS THE NORTHERN PLAINS...KEEPING A CHANCE OF
PRECIPITATION EACH DAY THROUGH EARLY NEXT WEEK.
THE OVERALL TEMPERATURE TREND IS FOR AVERAGE TEMPERATURES IN THE 70S
TO LOWER 80S FRIDAY...COOLING BY MONDAY TO THE LOW TO MID 70S.
&&
.AVIATION...
SOUTHERLY SURFACE WINDS TODAY AHEAD OF A COLD FRONT THAT IS FORECAST
TO ENTER WESTERN NORTH DAKOTA AFTER 18Z. IFR CIGS IN SOUTH DAKOTA
THIS MORNING ARE EXPECTED TO MOVE INTO THE KBIS/KJMS TAF SITES FOR A
FEW HOURS THIS MORNING...THEN SCATTER OUT FROM WEST TO EAST. WILL
WAIT FOR FINAL DETERMINATION ON THIS CLOSER TO TAF ISSUANCE TIME.
THE SURFACE COLD FRONT WILL BE ACCOMPANIED BY AN UPPER LEVEL
SHORTWAVE...WHICH WILL CREATE INCREASINGLY UNSTABLE CONDITIONS AND
WILL MENTION THUNDERSTORMS WITH VCTS GROUPS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...SCHECK
LONG TERM/AVIATION....JV
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
325 AM CDT WED JUN 13 2012
.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
325 AM CDT WED JUN 13 2012
MAIN FORECAST CONCERN DEALS WITH RAIN CHANCES TODAY THROUGH FRIDAY
NIGHT.
WATER VAPOR IMAGERY AND RAP ANALYSIS AT 2 AM SHOWS A DISTINCT
MID-LEVEL CYCLONIC CIRCULATION MOVING EAST ACROSS CENTRAL SD.
MOISTURE TRANSPORT AND ISENTROPIC LIFT AHEAD OF THE WAVE AIDING IN
SHOWERS AND ISOLATED THUNDERSTORMS ACROSS EASTERN SD/NEB...INTO
NORTHWEST IA. CLOSER TO HOME OVER OUR FORECAST AREA...HIGH CLOUDS
FROM THE DAKOTAS WAVE STREAMING IN WITH CENTER OF HIGH PRESSURE
ACROSS CENTRAL WI INTO CENTRAL LOWER MI. LIGHT WINDS AND PARTLY
CLOUDY CONDITIONS HAS ALLOWED TEMPERATURES TO DIP TO 37 DEGREES AT
BLACK RIVER FALLS WI...WHILE OTHER LOCATIONS RANGED FROM THE 40S TO
THE LOWER 50S UNDER MORE CLOUD COVER.
13.00Z NCEP MODEL SUITE/ECMWF/GEM GENERALLY IN GOOD AGREEMENT
THROUGH THE SHORT TERM PERIOD.
FOR TODAY...WILL BE WATCHING THAT MID-LEVEL WAVE OVER SD MOVES INTO
CENTRAL MN THROUGH THIS AFTERNOON. MODELS CONCENTRATE MAIN AXIS OF
ASSOCIATED 850MB MOISTURE TRANSPORT NORTHWEST INTO MN WITH OUR AREA
JUST ON THE EASTERN FRINGES. MEANWHILE...DECENT AMOUNT OF ISENTROPIC
LIFT INTO THE AREA FOR MID-CLOUD/ACCAS GENERATION. KEPT SMALL
CHANCES OF SHOWERS MAINLY NORTHWEST OF A LINE FROM MEDFORD AND
ARCADIA WI...TO ROCHESTER AND AUSTIN MN. OTHERWISE...WITH INCREASING
CLOUD COVER EXPECTED...HIGHS TODAY ARE EXPECTED TO TOP OFF IN THE
LOWER TO MIDDLE 70S.
TONIGHT...ANOTHER MID-LEVEL WAVE AND SURFACE CYCLOGENESIS WILL TAKE
PLACE OVER NEB/SD WITH MOISTURE TRANSPORT/ISENTROPIC LIFT IMPINGING
ON THE WESTERN PORTIONS OF THE FORECAST AREA. PLANNING ON ISOLATED
SHOWER AND ISOLATED THUNDER //WITH INCREASING ELEVATED MUCAPE//
NORTHWEST OF A MEDFORD-ARCADIA-ROCHESTER-AUSTIN LINE AGAIN IN THE
EVENING...THEN INCREASING SLIGHTLY IN COVERAGE/SPREADING EAST INTO
THE REST OF THE AREA AFTER MIDNIGHT AS 850MB MOISTURE TRANSPORT
VECTORS BEND MORE INTO THE AREA. RAINFALL LOOKS VERY LIGHT WITH
GENERALLY LESS THAN 5 HUNDRETHS OF AN INCH EXPECTED.
ON THURSDAY...LOOK FOR THE MID-LEVEL WAVE/SURFACE COLD FRONT TO MOVE
INTO MN WITH INCREASING 850MB MOISTURE TRANSPORT INTO THE AREA.
0-3KM MLCAPE INCREASES INTO THE 1000-1500J/KG RANGE ALONG AND AHEAD
OF THE FRONT JUST TO OUR WEST WITH RESPECTABLE 20-30KT 0-3KM BULK
SHEAR. THEREFORE...EXPECTING STRONGER THUNDERSTORM ACTIVITY ALONG
THE FRONT BY AFTERNOON WITH EASTERN FRINGES OF THIS ACTIVITY PERHAPS
MAKING IT INTO NORTHWEST PORTIONS OF THE FORECAST AREA. FOR
NOW...WILL STICK WITH 20-40 PERCENT SHOWER/THUNDERSTORM CHANCE
NORTHWEST OF A SPARTA-VIROQUA-OELWEIN LINE. OTHERWISE...LOOK FOR
HIGH TEMPERATURES IN THE UPPER 70S TO LOWER 80S.
FOR THURSDAY NIGHT THROUGH FRIDAY NIGHT...LOOK FOR THE COLD FRONT
OVER MN TO SINK INTO THE AREA WHILE WEAKENING. MEANWHILE...MODELS
SHOWING A COUPLE MID-LEVELS WAVE EJECTING NORTHEAST TOWARD/ACROSS
THE AREA WITH BOUTS OF LIFT/MOISTURE TRANSPORT. BASED ON THIS
SIGNAL...WILL GO WITH 30-50 SHOWER/THUNDERSTORM CHANCES FOR NOW FOR
THIS PERIOD.
.LONG TERM...SATURDAY THROUGH TUESDAY
325 AM CDT WED JUN 13 2012
13.00Z GFS/ECMWF SHOWING SOUTHWEST FLOW ALOFT INTO THE AREA THROUGH
THE PERIOD AS HIGH PRESSURE ANCHORS IN ACROSS THE EASTERN CONUS AND
A TROUGH SLOWLY MAKES ITS WAY ACROSS THE INTERMOUNTAIN WEST INTO THE
PLAINS. SIGNAL AGREEMENT BETWEEN THE MODELS SEEMS TO BE GETTING
STRONGER FOR PERIODIC SHOWER/THUNDERSTORM CHANCES THROUGH THE
WEEKEND. BOTH MODELS THEN BRING IN A DEEPER TROUGH/STRONGER SURFACE
COLD FRONT INTO THE AREA MONDAY THROUGH TUESDAY FOR CONTINUED
SHOWER/THUNDERSTORM CHANCES.
&&
.AVIATION...THROUGH 06Z THURSDAY
1145 PM CDT TUE JUN 12 2012
SURFACE HIGH PRESSURE OVER EASTERN WISCONSIN WILL CONTINUE TO DRIFT
EASTWARD OVERNIGHT AND WEDNESDAY. HIGH CLOUDS WERE ALREADY WORKING
THEIR WAY ACROSS MINNESOTA ON THE BACKSIDE OF THE HIGH AND WILL
CONTINUE TO OVERSPREAD THE TAF SITES TONIGHT. CEILINGS WILL LOWER
INTO THE 8K-12K FOOT RANGE AFTER 12Z. THE EDGE OF THE MOISTURE
TRANSPORT DOES CLIP SOUTHEAST MINNESOTA LATER WEDNESDAY AND THUS
EXPECT SOME SCATTERED SHOWERS. CONFIDENCE NOT HIGH THAT THESE WILL
IMPACT THE TAF SITES. SLIGHTLY BETTER CHANCES AFTER 00Z AS
MOISTURE CONTINUES TO INCREASE. DID ADD MENTION OF VCSH AT KRST
AFTER 00Z AND AT KLSE AFTER 03Z. OTHERWISE...EXPECT SOUTHERLY
WINDS TO GUST TO BETWEEN 20 AND 25 KNOTS AT KRST DURING THE
AFTERNOON HOURS WEDNESDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
325 AM CDT WED JUN 13 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...RABERDING
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
940 AM MDT WED JUN 13 2012
.UPDATE...NO CHANGES TO THE GRIDS AT THIS TIME. THE LATEST NAM12
FCST SOUNDINGS DOES INDICATE SOME MINIMAL CAPE AROUND 200 J/KG
THIS AFTN. NOT ENOUGH FOR TSTMS BUT BY ENOUGH TO PRODUCE SOME WEAK
CB BUILDUPS AND BRIEF GUSTY OUTFLOW WINDS. THE 12Z HRRR DEVELOPS
MINIMAL CELL COVERAGE AS WELL THIS AFTN WITH THE ACTIVITY EAST OF
THE DENVER AREA. OVERALL HOT AND DRY THE GOING THEME. WINDS AT THE
HIGH PARK WILDFIRE MAY BE SIMILAR TO YESTERDAY WITH W-SWLY WINDS
ON THE WEST SIDE...WITH MORE OF AN E-SELY COMPONENT ON THE EAST
SIDE. THE WINDS OVER THE BURN AREA MAY BECOME W-SWLY ON THE EAST
SIDE IN THE AFTN...AFTER 20Z. IN SPITE OF THE HOT AND DRY
CONDITIONS...WILL HOLD OFF ON ISSUING ANY FIRE WEATHER HIGHLIGHT
DUE TO THE LACK OF A STRONG SFC WIND COMPONENT.
&&
.AVIATION...VFR CONDITIONS OVER THE NEXT 24 HRS. THE MDLS DO HINT
AT SOME CELL DEVELOPMENT THIS AFTN...BUT WEAK AND EAST OF THE
DENVER AREA. SOME WEAK CB BUILDUPS NEAR D.I.A. COULD PRODUCE BRIEF
GUSTY OUTFLOW WINDS TO 25 KTS...BUT NOT ENOUGH CONFIDENCE TO ADD
IT TO THE TAF. A DRY COLD FRONT IS STILL PROGGED TO PUSH THROUGH
THE DENVER AREA OVERNIGHT...COULD BE SOONER...IN THE 09-12Z TIME
FRAME SO MAY ADJUST THE TIMING IN THE 18Z TAF ISSUANCE. ESELY
WINDS PROGGED THE LOW LEVEL MOISTURE ADVECTING INTO THE DENVER
AREA THROUGH THE DAY WEDNESDAY...SO THE PROSPECTS OF THUNDERSTORMS
BETTER IN THE AFTN SO WL ADD VCTS TO THE OUTLOOK PERIOD FOR D.I.A.
&&
.PREV DISCUSSION... /ISSUED 259 AM MDT WED JUN 13 2012/
SHORT TERM...THERE IS A CONTINUED MODERATE WESTERLY FLOW ALOFT
ACROSS COLORADO TODAY...WHICH WILL BE GRADUALLY SHIFTING MORE
SOUTHWESTERLY LATER TODAY AND TONIGHT. THE AIRMASS CONTINUES ON A
DRYING AND WARMING TREND. 700MB TEMPS RISE TO AROUND +16C AT
DENVER AND THIS WILL RESULT IN ANOTHER 4-6 DEGREES OF WARMING
TODAY. END RESULT WILL BE TEMPERATURES WELL INTO THE 90S ACROSS
LOWER ELEVATIONS. THE RECORD FOR DENVER TODAY IS 99 SO SHOULD BE
WELL SHORT OF THAT. FORECAST SOUNDINGS SHOW SOME MIDDLE LEVEL
MOISTURE BY LATER IN THE DAY BUT EXTREMELY DRY LOW LEVELS SHOULD
RESULT IN NO STORMS TODAY. THE ONLY EXCEPTION WOULD BE OVER THE
FAR EASTERN PLAINS OVER LINCOLN COUNTY TOWARDS EVENING WHERE LOW
LEVEL MOISTURE WOULD BE A BIT HIGHER. NOT EVEN THRILLED WITH
CHANCES OUT THERE BUT WILL LEAVE IN AN EVER SO SLIGHT CHANCE. IN
TERMS OF FIRE WEATHER CONCERNS IT WILL CERTAINLY BE WARM WITH LOW
HUMIDITIES 10-15 PERCENT BUT WIND GUSTS WILL GENERALLY BE BELOW
THRESHOLD NEEDED FOR ANY FIRE WEATHER HILITES. A FEW GUSTS IN THE
15-25 MPH RANGE CERTAINLY BUT NOT SUSTAINED AND WIDESPREAD ENOUGH
TO WARRANT ANY BIG FIRE CONCERNS. WIND SPEEDS SHOULD BE SIMILAR TO
YESTERDAY OVER MOUNTAINS AND FOOTHILLS.
LONG TERM...THURSDAY STARTS OUT WITH THE HIGH PLAINS CAPPED BY A
SHALLOW FRONTAL INVERSION WHICH IS TOPPED BY A WARM AND DRY
WESTERLY FLOW ASSOCIATED WITH A PASSING MID-LEVEL SHORTWAVE RIDGE.
LIGHT POST-FRONTAL EAST-NORTHEASTERLY WINDS ON THE PLAINS ARE
PROGGED TO TURN SOUTHEASTERLY LATE IN THE DAY WHICH ADVECTS
INCREASING AMOUNTS OF LOW-LEVEL MOISTURE UP AGAINST THE FRONT
RANGE DURING THE EVENING HOURS. THE RESULTANT DESTABILIZATION MAY
CAUSE A FEW GUSTY SHOWERS/T-STORMS TO FORM OVER AND NEAR THE FRONT
RANGE DURING THE EVENING. UNFORTUNATELY DO NOT SEE MUCH IN THE WAY
OF WETTING RAINFALL FROM THIS HIGH BASED CONVECTION. SO LIGHTNING
MAY POSE A THREAT FOR NEW FIRE IGNITIONS WHERE FUELS REMAIN QUITE
DRY. OVERNIGHT...MODELS SHOW LOW-LEVEL MOISTURE CONTINUING TO
FLOW INTO THE AREA ON SOUTHEASTERLY BOUNDARY LAYER WINDS...
POSSIBLY RESULTING IN POCKETS OF FOG TOWARDS MORNING.
ON FRIDAY...PATCHY FOG ON THE PLAINS IS EXPECTED TO BURN OFF BY
MID-MORNING WITH STRONG SOLAR HEATING. MODELS THEN SHOW A WEAK
SHORTWAVE TROUGH OVER THE 4-CORNERS AREA PASSING OVER THE
FORECAST AREA LATE IN THE DAY. COULD SEE CONVECTION BEGINNING IN
THE HIGH COUNTRY...NOT LONG AFTER MIDDAY WITH THE APPROACHING
SHORTWAVE. HOWEVER STORM COVERAGE IN THE HIGH COUNTRY PROBABLY NO
MORE THAN ISOLATED IN COVERAGE DUE TO A LACK OF MID-LEVEL
MOISTURE. AS THE LIFT GENERATED BY THIS WAVE INTERACTS WITH THE
RELATIVELY MOIST AND UNSTABLE AIR MASS ON THE PLAINS...COULD SEE
ISOLATED TO SCATTERED T-STORMS DEVELOPING DURING THE LATE
AFTERNOON AND EVENING HOURS. DOES NOT LOOK FAVORABLE FOR SEVERE
WEATHER...BUT CAN/T RULE OUT AN ISOLATED SEVERE STORM WITH
MOISTURE AROUND THIS TIME OF YEAR. LATER THAT NIGHT MAY SEE
PATCHING FOG FORMING AGAIN ON THE PLAINS ACCORDING TO THE NAM.
ON SATURDAY...MODELS SHOW THE DEEP UPPER LOW/TROUGH OVER THE
DESERT SOUTHWEST RETROGRADING WHICH ALLOWS A SECONDARY TROUGH TO
DROP SOUTH OUT OF IDAHO AND WESTERN WYOMING. MODELS SHOW THE
LEADING EDGE OF SLIGHTLY COOLER AND MORE MOIST AIR MASS SLIPPING
INTO NORTHEAST COLORADO DURING THE MORNING. THIS PUSH LOOKS
STRONGEST ON THE NAM. AS THE UPPER TROUGH SWINGS EAST ACROSS
WYOMING AND NORTHERN COLORADO DURING THE DAY...QG VERTICAL
VELOCITY FIELDS INDICATE WEAK UPPER MOTION OVER NORTHEAST COLORADO
DURING THE AFTERNOON AND EVENING HOURS. MODELS ALSO INDICATE
AREAS OF LIGHT QPF. THERE IS A SLIGHT CHANCE WE COULD SEE A
SEVERE STORM OR TWO ALONG A FRONTAL BOUNDARY WHICH THE NAM AND
CANADIAN GEM SHOW STRADDLED ACROSS THE NORTHEAST CORNER OF
COLORADO AROUND 00Z/SUN. CURRENT FORECAST GRIDS INDICATE 20-30
PERCENT POPS ACROSS THE AREA SATURDAY AFTERNOON AND EVENING. SEE
LITTLE REASON TO CHANGE THEM AT THIS TIME.
SUNDAY-TUESDAY...WITH THE UPPER TROUGH PASSING OVERHEAD SATURDAY
NIGHT...FLOW BOTH SFC AND ALOFT BECOME ZONAL ON SUNDAY...RESULTING
IN DRIER AND WARMER CONDITIONS AREA WIDE. HOWEVER THE GFS IS
SLOW TO DRY THINGS OUT EAST OF THE MTNS AS IT CONTINUES TO SHOW A
RELATIVELY MOIST SOUTH-SOUTHEAST LOW-LEVEL FLOW FOR MOST OF THE
DAY. WHILE AT THE SAME TIME IT SHOWS ZONAL FLOW ALOFT WITH WAVES
OF MID-LEVEL MOISTURE PASSING BY DURING THE DAY. FOR NOW WILL
LEAVE OUT ANY MENTION OF PRECIP ON SUNDAY. FOR MONDAY AND TUESDAY...
CONFIDENCE IN THE MODELS WAINS AS A FAST NORTHWESTERLY FLOW ON
THE BACK SIDE OF THE PASSING TROUGH MAKES IT DIFFICULT TO PIN DOWN
THE TIMING OF WEAK MID-LEVEL DISTURBANCES WHICH MODELS SHOW
PASSING OVERHEAD. SO WILL KEEP THINGS GENERALLY DRY WITH NEAR TO
SLIGHTLY ABOVE AVERAGE TEMPERATURES. AVERAGE TEMPERATURE FOR
DENVER ON THE MON/18TH AND TUE/19TH IS 83 AND 84...RESPECTIVELY.
AVIATION...LIGHT DRAINAGE WINDS THIS MORNING WILL GRADUALLY SHIFT
MORE SOUTHEAST LATER THIS AFTERNOON. VFR CONDITIONS THROUGH
TONIGHT. SOME SCT-BKN MIDDLE AND HIGH LEVEL MOISTURE LATER TODAY
BUT NO STORMS EXPECTED. THE NEXT COLD FRONT WILL MOVE THROUGH
TERMINALS THURSDAY MORNING...BETWEEN 12-15Z AS WINDS SHIFT
NORTHERLY. A DRY FRONT SO NO STRATUS/FOG IS EXPECTED AT THIS TIME.
HYDROLOGY...NO ISSUES THROUGH TONIGHT WITH A DRY FORECAST.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...COOPER
LONG TERM....BAKER
AVIATION...COOPER
AREA FORECAST DISCUSSION
NWS LINCOLN IL
948 AM CDT WED JUN 13 2012
.DISCUSSION...
ISSUED 947 AM CDT WED JUN 13 2012
THUNDERSTORM COMPLEX...ASSOCIATED WITH A SHORTWAVE OVER SOUTH
DAKOTA...HAS BEEN WEAKENING AS IT MOVES THROUGH WESTERN IOWA.
DRIER AIR OVER ILLINOIS WILL PREVENT THE RAIN FROM MAKING IT AS
FAR AS OUR AREA...BUT THICKENING MID AND HIGH CLOUDS FROM THIS
SYSTEM HAVE BEGUN MOVING INTO THE WESTERN CWA. LATEST LAYER
HUMIDITY PLOTS FROM THE RAP MODEL SHOWING THE THICKEST CLOUDS TO
PASS JUST TO OUR NORTH THROUGH MID AFTERNOON...WITH SCATTERED
CLOUDS SOUTHWARD OVER MOST OF THE CWA. HAVE SENT OUT SOME
ZONE/GRID UPDATES TO INCREASE THE CLOUD COVER SOMEWHAT OVER THE
NORTHERN CWA FOR TODAY. CURRENT TEMPERATURE FORECASTS LARGELY ARE
ON TRACK AND MADE ONLY VERY MINOR MODIFICATIONS BASED ON OBSERVED
TRENDS.
GEELHART
&&
.AVIATION...
ISSUED 644 AM CDT WED JUN 13 2012...FOR THE 12Z TAFS
VFR CONDITIONS WILL CONTINUE OVER THE NEXT 24 HOURS UNDER DRY
CANADIAN HIGH PRESSURE. CIRRUS CLOUDS FROM CONVECTIVE DEBRIS OVER
THE PLAINS SHOULD BE THE PRIMARY CLOUD COVER OVER THE TERMINALS
TODAY. THE LOW AND MID LEVELS WILL REMAIN TOO DRY FOR MUCH IN THE
WAY OF FAIR WEATHER CUMULUS.
LIKEWISE...VISIBILITY SHOULD REMAIN UNRESTRICTED DUE TO THE VERY
LOW SURFACE DEWPOINTS.
WINDS WILL CLIMB BETWEEN 10-12KT FROM THE ESE DURING THE
DAY...THEN DIMINISH BELOW 10KT BY SUNSET.
SHIMON
&&
.PREV DISCUSSION...
ISSUED 249 AM CDT WED JUN 13 2012
AT 06Z A BROAD AREA OF 1020 MB HIGH PRESSURE OCCUPIED MUCH OF THE
UPPER MIDWEST AND GREAT LAKES. UNDER THIS RIDGE CLEAR SKIES AND
LIGHT WINDS ALLOWED EARLY MORNING TEMPERATURES TO DIP INTO
THE SEASONABLY COOL 50S LOCALLY. AT THE MID LEVELS ZONAL FLOW
DOMINATED MUCH OF THE CENTRAL AND WESTERN U.S. WITH TROUGHING
AFFECTING THE EASTERN THIRD OF THE COUNTRY. A SHORTWAVE OVER THE
DAKOTAS WAS PRODUCING SOME SHOWERS AS FAR EAST AS WESTERN IOWA. AFTER
ANOTHER COMFORTABLE DAY TODAY...WARMING BEGINS THURSDAY THEN 90+
DEGREE HEAT IS EXPECTED FRIDAY THROUGH THE WEEKEND WHEN A MID LEVEL
RIDGE STRENGTHENS OVERHEAD. RAIN CHANCES INCREASE FROM THE NW
EARLY NEXT WEEK...OR WHEN THE RIDGE FINALLY SHIFTS FARTHER EAST.
SHORT TERM...TODAY THROUGH FRIDAY
AS THE HIGH SLIPS INTO THE EASTERN GREAT LAKES...EASTERLY LLVL
FLOW WILL KEEP TEMPS SIMILAR TO OBSERVED HIGHS YESTERDAY...IN THE
UPPER 70S/LOWER 80S. HUMIDITY LEVELS TO REMAIN REMARKABLY LOW FOR
MID JUNE WITH DEWPOINTS IN THE 40S. A SHORTWAVE CURRENTLY OVER THE
DAKOTAS WILL SHIFT INTO THE FAR UPPER MIDWEST KEEPING ANY PRECIP
NORTHWEST OF THE AREA...HOWEVER AN INCREASE IN MID/HIGH LEVEL CLOUDS
MAY PREVENT A SECOND COMPLETELY SUNNY DAY AT LEAST ACROSS THE
NORTHERN CWA. QUIET WEATHER PREVAILS OVERNIGHT WITH LOWS
MODERATING A FEW DEGREES FROM WHAT IS SEEN THIS MORNING. RETURN
SOUTHERLY FLOW COMMENCES ON THURSDAY IN CONCERT WITH RISING
HEIGHTS WILL PUSH TEMPS BACK UP NEAR SEASONAL NORMALS.
BY FRIDAY...LOW TO MID LEVEL THERMAL RIDGE BUILDS OVERHEAD AS A
LARGE MID LEVEL HIGH PRESSURE RIDGE STRENGTHENS FROM THE EASTERN
GREAT LAKES SOUTHWEST TOWARDS TX. THIS WILL RETURN HIGHS TO THE
90S. DRY SOILS WILL HELP KEEP DEWPOINTS IN CHECK...GRADUALLY
RISING THROUGH THE 50S FOR TOLERABLE HUMIDITY LEVELS.
LONG TERM...SATURDAY THROUGH TUESDAY
PRIMARY WEATHER FEATURES FOR THE EXTENDED PORTION OF THE FORECAST
ARE THE EXTENT/DURATION OF HEAT INTO EARLY NEXT WEEK...AND THE
POTENTIAL RETURN OF MUCH NEEDED RAINS BY MONDAY/TUESDAY OR LATER. EACH
OF THESE ELEMENTS WILL BE DETERMINED BY THE STRENGTH OF THE RIDGE
AND HOW QUICKLY IT SHIFTS FAR ENOUGH EAST TO ALLOW AN ACTIVE WX
PATTERN TO OUR NORTHWEST TO MOVE IN. FOR NOW WILL KEEP SLIGHT TO
LOW CHANCE POPS MONDAY/TUESDAY ACROSS THE NORTHWEST HALF WITH THE
ECMWF WEAKENING THE RIDGE QUICKER THAN GFS...WHICH WOULD ALLOW
ORGANIZED CONVECTION TO SETTLE SOUTHEAST TOWARDS CENTRAL IL. UNTIL
THE RIDGE DAMPENS...HIGHS IN THE LOWER 90S ARE LIKELY.
25
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
614 AM CDT WED JUN 13 2012
.AVIATION...12Z TAFS FOR KOMA...KLNK AND KOFK. VFR CONDITIONS
THROUGH THE PERIOD. SOUTHEAST WINDS AROUND 12 KNOTS DO INCREASE
WITH GUSTS UP TO 25 TO 28 KTS BY 15-17Z AND SHOULD CONTINUE UNTIL
ABOUT 14/01Z.
&&
.PREV DISCUSSION...
88D MOSAIC THIS MORNING SHOWING NARROW LINE OF BOWED-OUT ELEVATED
CONVECTION DRIVING EWD INTO ERN SD/ERN NEB. ACTIVITY WAS OCCURRING
WITHIN AREA OF STRONG LAYER DIFFERENTIAL DIVG/850MB WAA WITH A LLVL
MOIST FEED UP THRU THE CNTRL PLAINS. HRRR AND RAP SUGGESTING ACTIVITY
SHOULD BE OUT OF THE CWA SOMETIME AROUND RUSH HOUR.
ON THE WHOLE...MODELS CONTINUE TO BE IN REASONABLY GOOD AGREEMENT
THAT LARGE SCALE FLOW OVER THE NEXT WEEK WILL TRANSITION FROM NEAR
ZONAL OVER THE CONUS TO A RELATIVELY STAGNANT SITUATION WITH A BROAD
TROF COVERING THE WRN CONUS AND A RIDGE TO THE EAST. ALSO GOOD
AGREEMENT THAT BULK OF ACCUMULATING PCPN WILL GENERALLY OCCUR OVER
THE UPPER MIDWEST...ERN DAKOTAS...WRN IA...ERN NEB THRU DAY 7. ALL
THIS IN PART TO A PROLONGED MID LYR BNDRY ORIENTED PARALLEL TO SW-NE
FLOW ALOFT WITH SUSTAINED LLVL MOISTURE TO FEED ON PER MOISTURE
TRANSPORT PROGS. LIFTING MECHANISM THOUGH WILL BE MEANDERING SOMEWHAT
DURING THIS TIME...MAKING IT IMPOSSIBLE TO PIN DOWN POPS WITHIN THE
CWA. THUS...BECAUSE OF UNCERTAINTIES WILL OPT TO JUST BLANKET THE
AREA WITH SMALL POPS.
DEE
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
957 AM EDT WED JUN 13 2012
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE NORTH AND MOVE ACROSS THE AREA
THIS EVENING. SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
REDEVELOP ACROSS THE EASTERN CAROLINAS THIS AFTERNOON...WITH THE
BEST CHANCE ALONG THE COAST. HIGH PRESSURE WILL BUILD IN LATE
TONIGHT AND THURSDAY...BRINGING A RELATIVELY COOL AND DRY PATTERN
WHICH WILL PERSIST INTO NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM WEDNESDAY...SURFACE WINDS HAVE SHIFTED NORTHWESTERLY
ALL THE WAY DOWN TO THE BEACHES THIS MORNING AS A SURFACE TROUGH HAS
PUSHED OFF THE COAST. THE ACTUAL SURFACE COLD FRONT IS LAGGING THIS
WIND SHIFT AND SHOULD MAKE IT OFFSHORE EARLY THIS EVENING. WE`RE
LOSING THE DEEP TROPICAL MOISTURE AS MID-LEVEL WINDS HAVE SHIFTED
NORTHWESTERLY BEHIND A DEPARTING UPPER LEVEL TROUGH. PRECIPITABLE
WATER VALUES (CURRENTLY 1.75 INCHES) SHOULD FALL THROUGHOUT THE DAY
AND INTO TONIGHT AS DRIER AIR BUILDS IN MAINLY AT AND ABOVE 700 MB.
WITH MANY MORE BREAKS EXPECTED IN LOW AND MID-LEVEL CLOUD COVER
TODAY COMPARED TO THE PAST SEVERAL DAYS HIGH TEMPERATURES SHOULD
MAKE IT INTO THE 80S EVERYWHERE...WITH SOME UPPER 80S EVEN POSSIBLE
NEAR AND WEST OF LUMBERTON...DILLON AND FLORENCE. THIS WILL STEEPEN
LOW-LEVEL LAPSE RATES SIGNIFICANTLY AND SHOULD CREATE SCATTERED
SHOWERS AND STORMS THIS AFTERNOON. LATEST HRRR MODEL RUNS SHOW WE
SHOULD EXCEED CONVECTIVE TRIGGER TEMPERATURE BETWEEN 17-18Z...1-2 PM
EDT. LOWER PRECIP WATER VALUES WILL NOT BE ABLE TO COMPLETELY NEGATE
THE THREAT OF MORE HEAVY RAINFALL AND ISOLATED FLOODING DUE TO SLOW
CELL MOTION EXPECTED TO BE FROM NORTH TO SOUTH AT ONLY 10-12 MPH.
THERE WILL ALSO BE A THREAT OF GUSTY WINDS AS DRIER AIR ALOFT IS
ENTRAINED INTO THE STORM CELLS WITH DCAPE VALUES INCREASING TO 1000
J/KG OR MORE.
CONVECTIVE ACTIVITY SHOULD END FROM NORTH TO SOUTH THIS EVENING AS
THE ACTUAL COLD FRONT PUSHES OFFSHORE AND DRIER MORE STABLE AIR
BUILDS IN.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...MAIN FORECAST CHALLENGE FOR THE SHORT TERM
WILL BE TEMPERATURES AS MOISTURE WILL BE ON THE DECREASE AS AN OMEGA
CONFIGURATION DEVELOPS AT THE MID LEVELS. AT THE SURFACE A
FORMIDABLE NORTHEAST FLOW WILL DEVELOP AS HIGH PRESSURE BUILDS DOWN
FROM THE NORTHEAST AND LOW PRESSURE MEANDERS NEAR BERMUDA. MET
GUIDANCE IS QUITE A BIT WARMER AS OPPOSED TO THE MAV NUMBERS THROUGH
THE PERIOD MORE-SO THURSDAY. THIS APPEARS TO BE A FUNCTION OF
LINGERING LOW LEVEL MOISTURE VIA THE GFS. NUMBERS JOG TOWARD
SLIGHTLY BETTER AGREEMENT FRIDAY. HAVE LEANED TOWARD THE COOLER MAV
NUMBERS OPTING FOR A SLOWER PROGRESSION OF THE LOW LEVEL MOISTURE.
NO POPS THROUGH THE PERIOD.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 3 AM WEDNESDAY...NO SIGNIFICANT CHANGES TO THE MEDIUM RANGE
GUIDANCE THIS MORNING AS THE FORECAST AREA CONTINUES TO BE SITUATED
IN THE EASTERN PART OF A MID LEVEL OMEGA PATTERN FOR MOST OF THE
PERIOD. I DID INCREASE THE POPS INCREMENTALLY SUNDAY AND MONDAY TO
SLIGHT CHANCE TO MATCH HPC AND ADJACENT OFFICES VIA NORTHEAST
RESULTANT SEA BREEZE COMBINED WITH THE 700MB SUBSIDENCE INVERSION
ABATING. THE PATTERN BEGINS TO CHANGE LATE IN THE PERIOD WITH THE
GFS ADVERTISING A REX BLOCK DEVELOPING SO CONFIDENCE IS BELOW
AVERAGE. NO CHANGES TO TEMPERATURE FORECAST.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AS OF 12Z...MOST OF THE SIGNIFICANT CONVECTION IS OFFSHORE...
ASSOCIATED WITH A PRE-FRONTAL TROUGH. LOOK FOR LIGHT SHOWERS TO
AFFECT THE COASTAL TERMINALS FOR THE FIRST HOUR OR SO...ALONG WITH
INTERMITTENT STRATUS. LOW LEVELS BEGIN TO DRY OUT BY 13Z AS THE
WINDS SHIFT MORE TO THE NORTH AS THE COLD FRONT BEGINS TO PUSH
THROUGH. WILL HAVE TO WATCH THE STRATUS...CURRENT THINKING IS WE
WILL SEE A QUICK TRANSITION TO VFR BY MID MORNING...CONFIDENCE
MODERATE. SHOULD SEE PRETTY FULL SUN BY NOON TODAY. THERE COULD BE
ENOUGH HEATING TO KICK OFF SCATTERED LIGHT SHOWERS MAINLY ALONG THE
COAST THIS AFTERNOON. COVERAGE SHOULD BE LIMITED. TONIGHT...VFR
CONDITIONS WITH LIGHT NORTHEASTERLY WINDS.
EXTENDED OUTLOOK...MAINLY VFR THROUGH THE FORECAST PERIOD.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM WEDNESDAY...THUNDERSTORM ACTIVITY HAS PUSHED WELL
OFFSHORE AND INTO THE GULF STREAM...WITH LIGHTER SHOWERS NOW ENDING
ACROSS THE COASTAL WATERS. THERE SHOULD BE A LULL IN CONVECTION
LASTING THROUGH EARLY AFTERNOON BEFORE ADDITIONAL SHOWERS AND
THUNDERSTORMS DEVELOPING INLAND BEGIN TO MOVE OFFSHORE...AFFECTING
THE COASTAL WATERS THROUGH THIS EVENING. WINDS HAVE SHIFTED TO THE
WEST OR NORTHWEST THIS MORNING AS A TROUGH HAS PUSHED OFF THE COAST.
THE ACTUAL SURFACE COLD FRONT IS STILL WELL INLAND AND SHOULD WAIT
UNTIL THIS EVENING TO PUSH OFF THE COAST.
SEAS CURRENTLY RANGE FROM 2-3 FT NEAR THE COAST...BUT EARLIER
SHOWER/STORM ACTIVITY HAS BUILT SEAS TO AROUND 5 FT AT THE FRYING
PAN SHOALS BUOY AND AT THE OFFSHORE LEJEUNE BUOY. SEA HEIGHTS SHOULD
DIMINISH THROUGH EARLY EVENING...BUT MAY BEGIN TO BUILD LATER
TONIGHT AS INCREASING NORTHEAST WINDS DEVELOP BEHIND THE ACTUAL COLD
FRONT.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...A NORTHEASTERLY FLOW WILL PREVAIL
THROUGHOUT THE PERIOD AS HIGH PRESSURE BUILDS DOWN FROM THE
NORTHEAST AND LOW PRESSURE SLOWLY DEVELOPS WELL INTO THE ATLANTIC.
STRONGEST WINDS OCCUR LATE FRIDAY WHEN THE 20-25 KNOT RANGE WILL
LIKELY BE CLOSER TO THE HIGH END OF THE RANGE. THE PERSISTENT FETCH
WILL ALLOW SEAS TO BUILD LATE THURSDAY TO ECLIPSE THE SIX FOOT SMALL
CRAFT CRITERIA AND CONTINUE THROUGH THE REMAINDER OF THE PERIOD.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3 AM WEDNESDAY...ESSENTIALLY NO CHANGES TO THE EXTENDED
COASTAL WATERS FORECAST AS A NORTHEASTERLY FLOW SHOULD PREVAIL. MAY
SEE MORE VEERING SUNDAY AFTERNOON AS THE FLOW IS LIGHTER ALLOWING
MORE OF A NORTHEAST RESULTANT TO DEVELOP. THE CAVEAT WITH THIS TYPE
OF SCENARIO ARE THE EMBEDDED SURGES. I DID WALK BACK SEAS SLIGHTLY
BUT A SMALL CRAFT ADVISORY MAY STILL BE NEEDED BUT IT APPEARS MORE
MARGINAL AT THIS POINT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...DL
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
634 AM CDT WED JUN 13 2012
.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
325 AM CDT WED JUN 13 2012
MAIN FORECAST CONCERN DEALS WITH RAIN CHANCES TODAY THROUGH FRIDAY
NIGHT.
WATER VAPOR IMAGERY AND RAP ANALYSIS AT 2 AM SHOWS A DISTINCT
MID-LEVEL CYCLONIC CIRCULATION MOVING EAST ACROSS CENTRAL SD.
MOISTURE TRANSPORT AND ISENTROPIC LIFT AHEAD OF THE WAVE AIDING IN
SHOWERS AND ISOLATED THUNDERSTORMS ACROSS EASTERN SD/NEB...INTO
NORTHWEST IA. CLOSER TO HOME OVER OUR FORECAST AREA...HIGH CLOUDS
FROM THE DAKOTAS WAVE STREAMING IN WITH CENTER OF HIGH PRESSURE
ACROSS CENTRAL WI INTO CENTRAL LOWER MI. LIGHT WINDS AND PARTLY
CLOUDY CONDITIONS HAS ALLOWED TEMPERATURES TO DIP TO 37 DEGREES AT
BLACK RIVER FALLS WI...WHILE OTHER LOCATIONS RANGED FROM THE 40S TO
THE LOWER 50S UNDER MORE CLOUD COVER.
13.00Z NCEP MODEL SUITE/ECMWF/GEM GENERALLY IN GOOD AGREEMENT
THROUGH THE SHORT TERM PERIOD.
FOR TODAY...WILL BE WATCHING THAT MID-LEVEL WAVE OVER SD MOVES INTO
CENTRAL MN THROUGH THIS AFTERNOON. MODELS CONCENTRATE MAIN AXIS OF
ASSOCIATED 850MB MOISTURE TRANSPORT NORTHWEST INTO MN WITH OUR AREA
JUST ON THE EASTERN FRINGES. MEANWHILE...DECENT AMOUNT OF ISENTROPIC
LIFT INTO THE AREA FOR MID-CLOUD/ACCAS GENERATION. KEPT SMALL
CHANCES OF SHOWERS MAINLY NORTHWEST OF A LINE FROM MEDFORD AND
ARCADIA WI...TO ROCHESTER AND AUSTIN MN. OTHERWISE...WITH INCREASING
CLOUD COVER EXPECTED...HIGHS TODAY ARE EXPECTED TO TOP OFF IN THE
LOWER TO MIDDLE 70S.
TONIGHT...ANOTHER MID-LEVEL WAVE AND SURFACE CYCLOGENESIS WILL TAKE
PLACE OVER NEB/SD WITH MOISTURE TRANSPORT/ISENTROPIC LIFT IMPINGING
ON THE WESTERN PORTIONS OF THE FORECAST AREA. PLANNING ON ISOLATED
SHOWER AND ISOLATED THUNDER //WITH INCREASING ELEVATED MUCAPE//
NORTHWEST OF A MEDFORD-ARCADIA-ROCHESTER-AUSTIN LINE AGAIN IN THE
EVENING...THEN INCREASING SLIGHTLY IN COVERAGE/SPREADING EAST INTO
THE REST OF THE AREA AFTER MIDNIGHT AS 850MB MOISTURE TRANSPORT
VECTORS BEND MORE INTO THE AREA. RAINFALL LOOKS VERY LIGHT WITH
GENERALLY LESS THAN 5 HUNDRETHS OF AN INCH EXPECTED.
ON THURSDAY...LOOK FOR THE MID-LEVEL WAVE/SURFACE COLD FRONT TO MOVE
INTO MN WITH INCREASING 850MB MOISTURE TRANSPORT INTO THE AREA.
0-3KM MLCAPE INCREASES INTO THE 1000-1500J/KG RANGE ALONG AND AHEAD
OF THE FRONT JUST TO OUR WEST WITH RESPECTABLE 20-30KT 0-3KM BULK
SHEAR. THEREFORE...EXPECTING STRONGER THUNDERSTORM ACTIVITY ALONG
THE FRONT BY AFTERNOON WITH EASTERN FRINGES OF THIS ACTIVITY PERHAPS
MAKING IT INTO NORTHWEST PORTIONS OF THE FORECAST AREA. FOR
NOW...WILL STICK WITH 20-40 PERCENT SHOWER/THUNDERSTORM CHANCE
NORTHWEST OF A SPARTA-VIROQUA-OELWEIN LINE. OTHERWISE...LOOK FOR
HIGH TEMPERATURES IN THE UPPER 70S TO LOWER 80S.
FOR THURSDAY NIGHT THROUGH FRIDAY NIGHT...LOOK FOR THE COLD FRONT
OVER MN TO SINK INTO THE AREA WHILE WEAKENING. MEANWHILE...MODELS
SHOWING A COUPLE MID-LEVELS WAVE EJECTING NORTHEAST TOWARD/ACROSS
THE AREA WITH BOUTS OF LIFT/MOISTURE TRANSPORT. BASED ON THIS
SIGNAL...WILL GO WITH 30-50 SHOWER/THUNDERSTORM CHANCES FOR NOW FOR
THIS PERIOD.
.LONG TERM...SATURDAY THROUGH TUESDAY
325 AM CDT WED JUN 13 2012
13.00Z GFS/ECMWF SHOWING SOUTHWEST FLOW ALOFT INTO THE AREA THROUGH
THE PERIOD AS HIGH PRESSURE ANCHORS IN ACROSS THE EASTERN CONUS AND
A TROUGH SLOWLY MAKES ITS WAY ACROSS THE INTERMOUNTAIN WEST INTO THE
PLAINS. SIGNAL AGREEMENT BETWEEN THE MODELS SEEMS TO BE GETTING
STRONGER FOR PERIODIC SHOWER/THUNDERSTORM CHANCES THROUGH THE
WEEKEND. BOTH MODELS THEN BRING IN A DEEPER TROUGH/STRONGER SURFACE
COLD FRONT INTO THE AREA MONDAY THROUGH TUESDAY FOR CONTINUED
SHOWER/THUNDERSTORM CHANCES.
&&
.AVIATION...TODAY AND TONIGHT
634 AM CDT WED JUN 13 2012
A SOUTH-SOUTHEAST FLOW WILL HELP HOLD DRY AIR IN PLACE IN THE
LOWER LEVELS OF THE ATMOSHPERE...RESULTING IN CONDITIONS REMAINING
VFR THROUGH TONIGHT. THIS FLOW ORIGINATES OUT OF HIGH PRESSURE
MOVING EAST INTO THE GREAT LAKES. ABOVE THIS DRY AIR...MOISTURE
WILL RETURN FROM THE GULF OF MEXICO AHEAD OF A LOW PRESSURE SYSTEM
IN THE DAKOTAS. A FEW SHOWERS AND PERHAPS EVEN THUNDERSTORMS COULD
IMPACT THE KRST TAF SITE AFTER MIDNIGHT...ON THE NOSE OF THIS
MOISTURE RETURN. HOWEVER...CONFIDENCE IS ONLY HIGH ENOUGH TO PUT A
VCSH IN AFTER 06Z. OTHER SHOWERS CURRENTLY PRESENT ON RADAR AROUND
THE SIOUX FALLS AREA ARE EXPECTED TO WEAKEN AND HEAD OFF TO THE
NORTHWEST...STAYING MOSTLY AWAY FROM KRST AND KLSE. REGARDING THE
SOUTH-SOUTHEAST FLOW...THE WINDS SHOULD BECOME GUSTY AT KRST WITH
GUSTS TO 20 KT DUE TO DAYTIME HEATING AND A TIGHTER PRESSURE
GRADIENT THAN AT KLSE. THESE GUSTS WILL END THIS EVENING WITH LOSS
OF HEATING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
325 AM CDT WED JUN 13 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
333 PM EDT WED JUN 13 2012
.SYNOPSIS...
LOW PRESSURE TO OUR EAST WILL CONTINUE TO PULL FURTHER OFFSHORE
TONIGHT WHILE HIGH PRESSURE NOSES IN FROM THE NORTHWEST. THIS RIDGE
WILL REMAIN COMPLACENT OVER THE REGION THURSDAY THROUGH WEDNESDAY OF
NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
THE WRF-NMMB LOOKED BETTER THAN THE GFS WITH ITS 500MB
INITIALIZATION IN THE NERN CONUS, THE GFS LOOKED BETTER IN OTHER
PLACES EAST. ALSO THE GFS LOOKED SLIGHTLY BETTER AT 850MB AND 925MB.
IN TERMS OF VERIFYING "WHAT IS OUT THERE", THE GFS AND CAN RGEM
LOOKED SLIGHTLY BETTER THAN THE WRF-NMMB. SO THE PLAN IS TO LEAN
TOWARD THE GFS THROUGH THE SHORT TERM AND MOVE THE CHANCES FASTER
THROUGH OUR CWA TONIGHT. THE HRRR WAS NOT USED AS ITS WAVES OF
SHOWERS REACHING INTO PA IS AND HAS NOT BEEN VERIFYING.
SHOWERS CHANCES ARE TIED TO A COMBINATION OF THE GFS, CAN RGEM AND
4KM ARW SOLUTIONS. NOT MUCH DPVA FORECAST BEYOND MIDNIGHT AND NO
OTHER FORCING APPARENT. SOME COASTAL FRICTIONAL CONVERGENCE HELPING
NOW ALONG THE INVERTED TROF. AS THE OFFSHORE LOW SAGS SOUTH, SO
SHOULD THE GREATER CONVERGENCE/SFC TROF AND HENCE THE SOUTHWARD SAG
OF POPS.
OTHERWISE EXPERIMENTAL SATELLITE IMAGERY IS SHOWING A FAIRLY LARGE
SWATH OF MVFR WITH LOW PROBABILITY IFR CIGS OFFSHORE. AS THE SFC LOW
SAGS SOUTHWARD, THE WINDS WILL VEER MORE TOWARD THE ONSHORE
DIRECTION. WITH THE FORECAST SOUNDINGS DEVELOPING AN INVERSION, THIS
SHOULD TRAP THE CLOUDS AND HELP SPREAD IT WESTWARD INTO OUR CWA.
RIGHT NOW WE ARE LEANING MORE TOWARD CLOUDINESS THAN FOG. WE ARE
MAKING SKY COVER MORE PESSIMISTIC TONIGHT. CONFIDENCE AS TO HOW FAR
WEST THIS GETS IS NOT HIGH. BECAUSE WE ARE GOING WITH THE CLOUDIER
FORECAST, WE ARE ALSO GOING WITH HIGHER STAT GUIDANCE MINIMUM
TEMPERATURES.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
ONCE THE STRATOCU CEILING IN OUR CWA GETS ESTABLISHED, THE CONTINUING
ONSHORE FLOW MAY HELP TAKE IT A WHILE LONGER THAN TYPICALLY FOR JUNE
FOR SUNSHINE TO DEVELOP ON THURSDAY. WE HAVE GONE THE CONSERVATIVE
ROUTE WITH THE SUNSHINE. ONE KNOWN WEAKNESS OF THE NEW VERSION OF
THE GFS IS EVEN A MORE GENEROUS WET BIAS WITH THE .01 ISOHYET. AT
THE RISK OF PUTTING OUR FOOT IN OUR MOUTHS, THAT IS WHAT THE GFS
LOOKS LIKE ITS DOING IN OUR CWA TOMORROW. ITS GETTING THERE BY
POOLING DEW POINTS INTO THE MID 60S AND GENERATING SOME WEAK CAPE.
ITS OWN STAT GUIDANCE HAS DEW POINTS 5 TO 8F LOWER AND WITHOUT THOSE
DEW POINTS, THE CHANCES GET THAT MUCH LOWER. EVEN WITH FULL SUN AND
OFF THE FORECAST 925MB TEMPERATURES, GFS MOS MAX TEMPS LOOK TOO
WARM. MAX TEMPS CLOSER TO NAM MOS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
5-WAVE MODEL GUIDANCE SHOWS BLOCKING TO OUR NORTHEAST WHERE A
LONGWAVE TROUGH HAS RESIDED FOR THE PAST COUPLE OF DAYS. RIDGING
WILL MOVE INTO THE REGION BY FRIDAY ORIENTED SOUTHWEST TO NORTHEAST.
THIS WILL PROVIDE A STAGNANT PATTERN THROUGH MID-WEEK NEXT WEEK. IT
WILL PROVIDE DRY CONDITIONS WITH SLIGHTLY BELOW NORMAL TEMPERATURES
TO START THE PERIOD. WITH THE STAGNANT PATTERN CONFIDENCE IN THE
LONGTERM FORECAST IS HIGH.
AS THE MID-LEVEL AND SURFACE RIDGING MOVE EVER SO SLIGHTLY TO OUR
EAST ON SUNDAY AND MONDAY OUR SURFACE FLOW WILL TURN MORE TOWARDS
THE SOUTH-SOUTHEAST. THIS WILL ALLOW THICKNESSES TO INCREASE AS
WARMER, MOISTER AIR IS ADVECTED INTO OUR REGION. TEMPERATURES WILL
BEGIN A SLOW UPWARD TREND STARTING ON MONDAY THROUGH THE REMAINDER
OF THE PERIOD.
WITH THE NORTHEASTERLY FLOW TURNING MORE EASTERLY BY SATURDAY WE
WILL SEE DIURNALLY DRIVEN CLOUDS AT NIGHT THROUGH WEDNESDAY...BETTER
CHANCES CLOSER TO THE COAST. DURING THE OVERNIGHT HOURS WE WILL SEE
MOISTURE POOLING IN THE LOW-LEVELS WHICH COULD PRODUCE PROLONGED
PERIODS OF FOG AND OVERCAST CONDITIONS...MOST OF THE LOWER CLOUDS
AND FOG WILL BURN OFF DURING THE MORNING HOURS.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
A TRENDING TOWARD MVFR TAF PACKAGE WAS ISSUED WITH THE 18Z TAFS,
ALTHOUGH CONFIDENCE IS LOWER THAN AVERAGE. THE EASTWARD ADVANCE OF
THE LOWER CLOUDS HAS HIT THE WALL AND THEY ARE SLOWLY ADVANCING
TO THE WEST. SOME SHOWERS ARE EXPECTED TO REMAIN JUST EAST
OF KACY. WE EXPECT THE EASTERN NJ AIRPORTS AND KACY TAF SITE TO
REMAIN MVFR WITH SOME WESTWARD PROGRESSION IN NJ. THE PA AND
DELMARVA AIRPORTS SHOULD REMAIN VFR WITH SOME CUMULUS AND CIRRUS
CLOUDS. GUSTY NORTH WINDS (20 TO 25 KT GUSTS) SHOULD CONTINUE
THROUGH THE AFTERNOON WITH A SLOW VEERING TO THE NORTHEAST.
FOR THIS EVENING WE ARE EXPECTING THE MVFR CIGS TO ADVANCE WESTWARD
EVEN MORE AS IT PROGRESSES. GREATEST CONFIDENCE OF MVFR CONDITIONS
EASTERN TERMINALS, LESS CONFIDENCE ABOUT IT REACHING KABE AND KRDG.
THE WESTERN EDGE OF SHOWERS WILL CONTINUE TO BE NEAR KACY AND KMIV.
NOT ENOUGH CONFIDENCE TO INCLUDE. FORECAST SOUNDINGS SUGGESTING SOME
GUSTINESS MAY CONTINUE INTO THE EVENING, ESPECIALLY EASTERN
TERMINALS. WE BELIEVE THERE WILL BE EITHER TOO MANY CLOUDS OR WINDS
FOR FOG TO FORM OVERNIGHT.
ONCE THE MVFR CIG ARRIVES, IT MAY TAKE A WHILE FOR IT TO DISSIPATE
ON THURSDAY. SO OTHER THAN OUR NW TERMINALS, WE KEPT MVFR CIGS
GOING THROUGH THE MORNING. SOME GUSTINESS FROM THE NORTHEAST
(SLIGHTLY LOWER THAN TODAY) WINDS SHOULD RETURN IN THE MORNING.
THE OVERALL GRADIENT IS EXPECTED TO RELAX DURING THURSDAY
AFTERNOON WHICH MIGHT BE A WINDOW TO HAVE CLOUDS DISSIPATE OR RISE
TO VFR CIGS.
OUTLOOK...
THU NIGHT - WEDNESDAY... VFR CONDITIONS WITH EAST-NORTHEAST WINDS.
POSSIBLE LOCAL MVFR CONDITIONS DURING THE OVERNIGHT AND EARLY
MORNING HOURS...MAINLY EAST OF PHILADELPHIA.
&&
.MARINE...
WE WILL EXTEND THE SCA ON DELAWARE BAY THROUGH THE NIGHT. FORECAST
SOUNDINGS ARE NOW SHOWING SMALL CRAFT ADVISORY WINDS NEAR THE TOP OF
THE MIXING LEVEL THROUGH THE NIGHT. IT IS PROBABLE THAT WE WILL GO
BELOW SMALL CRAFT ADVISORY LEVEL GUSTS FROM TIME TO TIME THE REST OF
THIS AFTERNOON AND EVENING, BUT AS AIR TEMPERATURES EDGE BELOW THE
WATER TEMPERATURES OVERNIGHT, THERE MAY BE ANOTHER WINDOW FOR MORE
FREQUENT SCA LEVEL GUSTS. THE OVERALL GRADIENT IS EXPECTED
TO BE LESSEN ON THURSDAY, SO THE CHANCES FOR SCA CRITERIA WILL
DECREASE AS THE DAY PROGRESSES ON THE BAY.
ON THE OCEAN, SMALL CRAFT ADVISORY LEVEL WINDS SHOULD OCCUR TONIGHT
AND THEN INTO THURSDAY ON THE SOUTHERN WATERS. SWELLS WILL BE A
CONTINUING AND LAGGING ISSUE ONCE THE WINDS CEASE AS THE OVERALL
ONSHORE FLOW SHOULD PERSIST FOR A WHILE. WE DID NOT EXTEND THE SCA
ON THE OCEAN FOR EITHER SEGMENTS, BUT SOME ADJUSTMENTS MAY BECOME
NECESSARY AS CONFIDENCE INCREASES.
OUTLOOK...
HIGH PRESSURE WILL BUILD IN FROM THE NORTHWEST AND SLIDE TO OUR
NORTHEAST BY SATURDAY. THIS WILL PROVIDE DRY WEATHER ALTHOUGH WITH AN
ONSHORE FLOW WE COULD STILL HAVE SOME LINGERING ISSUES WITH SWELLS
ACROSS OUR SOUTHERN WATERS THROUGH SATURDAY. AFTER THAT SEAS WILL
BECOME MORE TRANQUIL AS WE LOSS THE SWELLS.
&&
.RIP CURRENTS...
THE COMBINATION OF LARGE...8 SECOND PERIOD SWELLS AND FAIRLY HIGH
SURF ZONE WAVES WILL INTERACT TO CREATE A HIGH RISK OF RIP CURRENTS
FOR BOTH THE NEW JERSEY AND DELAWARE COASTS FOR THURSDAY. DUE TO THE
HIGH RISK...A HIGH RIP CURRENT RISK HEADLINE WILL BE ISSUED FOR
THURSDAY. THE DETAILS OF THE HIGH RIP CURRENT RISK CAN BE FOUND IN
THE COASTAL HAZARD MESSAGE PRODUCT /AWIPS HEADER PHLCFWPHI/.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...HIGH RIP CURRENT RISK FROM THURSDAY MORNING THROUGH THURSDAY
EVENING FOR NJZ014-024>026.
DE...HIGH RIP CURRENT RISK FROM THURSDAY MORNING THROUGH THURSDAY
EVENING FOR DEZ004.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 9 PM EDT THURSDAY FOR ANZ452>455.
SMALL CRAFT ADVISORY UNTIL 7 AM EDT THURSDAY FOR ANZ430-431-
450-451.
&&
$$
SYNOPSIS...HEAVENER
NEAR TERM...GIGI
SHORT TERM...GIGI
LONG TERM...HEAVENER
AVIATION...GIGI/HEAVENER
MARINE...GIGI/HEAVENER
RIP CURRENTS...HAYES
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1208 PM CDT WED JUN 13 2012
.DISCUSSION...
ISSUED 947 AM CDT WED JUN 13 2012
THUNDERSTORM COMPLEX...ASSOCIATED WITH A SHORTWAVE OVER SOUTH
DAKOTA...HAS BEEN WEAKENING AS IT MOVES THROUGH WESTERN IOWA.
DRIER AIR OVER ILLINOIS WILL PREVENT THE RAIN FROM MAKING IT AS
FAR AS OUR AREA...BUT THICKENING MID AND HIGH CLOUDS FROM THIS
SYSTEM HAVE BEGUN MOVING INTO THE WESTERN CWA. LATEST LAYER
HUMIDITY PLOTS FROM THE RAP MODEL SHOWING THE THICKEST CLOUDS TO
PASS JUST TO OUR NORTH THROUGH MID AFTERNOON...WITH SCATTERED
CLOUDS SOUTHWARD OVER MOST OF THE CWA. HAVE SENT OUT SOME
ZONE/GRID UPDATES TO INCREASE THE CLOUD COVER SOMEWHAT OVER THE
NORTHERN CWA FOR TODAY. CURRENT TEMPERATURE FORECASTS LARGELY ARE
ON TRACK AND MADE ONLY VERY MINOR MODIFICATIONS BASED ON OBSERVED
TRENDS.
GEELHART
&&
.AVIATION...
ISSUED 1207 PM CDT WED JUN 13 2012
EASTERLY WINDS WILL PERSIST THROUGH ABOUT 06Z...BEFORE TRENDING
SOUTHEAST AS A COLD FRONT BEGINS TO PUSH THROUGH THE CENTRAL
PLAINS. SOME INCREASE IN SPEED IS EXPECTED TOWARD THE END OF THE
PERIOD AS THE FRONT GETS CLOSER. EXPECT PERIODIC CLOUD COVER TO
REMAIN AT OR ABOVE 12 KFT DUE TO DRY AIR IN THE LOWER LEVELS OF
THE ATMOSPHERE.
GEELHART
&&
.PREV DISCUSSION...
ISSUED 249 AM CDT WED JUN 13 2012
AT 06Z A BROAD AREA OF 1020 MB HIGH PRESSURE OCCUPIED MUCH OF THE
UPPER MIDWEST AND GREAT LAKES. UNDER THIS RIDGE CLEAR SKIES AND
LIGHT WINDS ALLOWED EARLY MORNING TEMPERATURES TO DIP INTO
THE SEASONABLY COOL 50S LOCALLY. AT THE MID LEVELS ZONAL FLOW
DOMINATED MUCH OF THE CENTRAL AND WESTERN U.S. WITH TROUGHING
AFFECTING THE EASTERN THIRD OF THE COUNTRY. A SHORTWAVE OVER THE
DAKOTAS WAS PRODUCING SOME SHOWERS AS FAR EAST AS WESTERN IOWA. AFTER
ANOTHER COMFORTABLE DAY TODAY...WARMING BEGINS THURSDAY THEN 90+
DEGREE HEAT IS EXPECTED FRIDAY THROUGH THE WEEKEND WHEN A MID LEVEL
RIDGE STRENGTHENS OVERHEAD. RAIN CHANCES INCREASE FROM THE NW
EARLY NEXT WEEK...OR WHEN THE RIDGE FINALLY SHIFTS FARTHER EAST.
SHORT TERM...TODAY THROUGH FRIDAY
AS THE HIGH SLIPS INTO THE EASTERN GREAT LAKES...EASTERLY LLVL
FLOW WILL KEEP TEMPS SIMILAR TO OBSERVED HIGHS YESTERDAY...IN THE
UPPER 70S/LOWER 80S. HUMIDITY LEVELS TO REMAIN REMARKABLY LOW FOR
MID JUNE WITH DEWPOINTS IN THE 40S. A SHORTWAVE CURRENTLY OVER THE
DAKOTAS WILL SHIFT INTO THE FAR UPPER MIDWEST KEEPING ANY PRECIP
NORTHWEST OF THE AREA...HOWEVER AN INCREASE IN MID/HIGH LEVEL CLOUDS
MAY PREVENT A SECOND COMPLETELY SUNNY DAY AT LEAST ACROSS THE
NORTHERN CWA. QUIET WEATHER PREVAILS OVERNIGHT WITH LOWS
MODERATING A FEW DEGREES FROM WHAT IS SEEN THIS MORNING. RETURN
SOUTHERLY FLOW COMMENCES ON THURSDAY IN CONCERT WITH RISING
HEIGHTS WILL PUSH TEMPS BACK UP NEAR SEASONAL NORMALS.
BY FRIDAY...LOW TO MID LEVEL THERMAL RIDGE BUILDS OVERHEAD AS A
LARGE MID LEVEL HIGH PRESSURE RIDGE STRENGTHENS FROM THE EASTERN
GREAT LAKES SOUTHWEST TOWARDS TX. THIS WILL RETURN HIGHS TO THE
90S. DRY SOILS WILL HELP KEEP DEWPOINTS IN CHECK...GRADUALLY
RISING THROUGH THE 50S FOR TOLERABLE HUMIDITY LEVELS.
LONG TERM...SATURDAY THROUGH TUESDAY
PRIMARY WEATHER FEATURES FOR THE EXTENDED PORTION OF THE FORECAST
ARE THE EXTENT/DURATION OF HEAT INTO EARLY NEXT WEEK...AND THE
POTENTIAL RETURN OF MUCH NEEDED RAINS BY MONDAY/TUESDAY OR LATER. EACH
OF THESE ELEMENTS WILL BE DETERMINED BY THE STRENGTH OF THE RIDGE
AND HOW QUICKLY IT SHIFTS FAR ENOUGH EAST TO ALLOW AN ACTIVE WX
PATTERN TO OUR NORTHWEST TO MOVE IN. FOR NOW WILL KEEP SLIGHT TO
LOW CHANCE POPS MONDAY/TUESDAY ACROSS THE NORTHWEST HALF WITH THE
ECMWF WEAKENING THE RIDGE QUICKER THAN GFS...WHICH WOULD ALLOW
ORGANIZED CONVECTION TO SETTLE SOUTHEAST TOWARDS CENTRAL IL. UNTIL
THE RIDGE DAMPENS...HIGHS IN THE LOWER 90S ARE LIKELY.
25
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
351 PM CDT WED JUN 13 2012
.SYNOPSIS...
ISSUED AT 342 PM CDT WED JUN 13 2012
A BROAD WEAK, ZONAL MID LEVEL FLOW PATTERN WA IN PLACE ACROSS
WESTERN KANSAS. INCREASING BOUNDARY LAYER MOISTURE WAS OCCURRING AS
SOUTHERLY WINDS TRANSPORTED HIGHER CONTENT MOISTURE AIR FROM
WESTERN OKLAHOMA AND THE PANHANDLES. FARTHER WEST, A DRYLINE WAS
EVIDENT IN THE MESONET POINT DATA ACROSS SOUTHEAST COLORADO, AS WELL
AS IN A FINE LINE DEVELOPING ON KPUX RADAR FROM LAMAR, CO
SOUTHWEST.
&&
.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 342 PM CDT WED JUN 13 2012
THE SHORT TERM MODELS HANDLE THE EVOLUTION OF CONVECTION THIS EVENING
VERY DIFFERENTLY AND THERE IS RELATIVELY LOW CONFIDENCE IN THIS
NEAR TERM FORECAST. THE 12UTC NAM MODEL WOULD INDICATE AND STORMS
THAT DEVELOP REMAIN ANCHORED TO THE MUCH HIGHER CAPE/INSTABILITY
AXIS OF THE HIGH PLAINS OF COLORADO INTO THE WEST TEXAS PANHANDLE
THIS EVENING. AT HIS TIME, THIS NAM SOLUTION SEEMS TO BE MORE
LIKELY THAN OTHERS BASED ON THE WEAK FORCING ENVIRONMENT WE ARE
DEALING WITH. HOWEVER, WE CANNOT COMPLETELY IGNORE THE RECENT
ARW-WRF/NMM RUNS AND HRRR THAT HAVE ELUDED TO CONVECTION OVER
EASTERN COLORADO LATER THIS AFTERNOON DEVELOPING A COLD POOL AND
SPREADING RAPIDLY INTO THE WESTERN SEVERAL TIERS OF COUNTIES IN THE
EVENING HOURS. IF THAT DOES OCCUR, THE MOST PLAUSIBLE OUTCOME WOULD
SEEM TO BE MARGINALLY ISOLATED SEVERE THUNDERSTORM WIND GUSTS AND
PERHAPS ISOLATED HAIL PUSHING SEVERE LIMITS OF AN INCH AT MOST.
HOWEVER, THE WEAKER CONVECTION COULD SPREAD FOR SEVERAL HOURS
EASTWARD INTO CENTRAL KANSAS DURING THE LATE EVENING.
CONVECTIVE CHANCES ARE JUST AS GOOD OR BETTER ALONG A STRENGTHENING
COLD FRONTAL BOUNDARY WHICH SHOULD UNDERGO FRONTOGENESIS FROM WEST
CENTRAL KANSAS INTO NORTH CENTRAL KANSAS DURING THE VERY LATE
AFTERNOON INTO THURSDAY EVENING. THIS WILL BE BE WEAK FORCING,
BUT PERHAPS MORE MODERATE CAPE VALUES BY LATE IN THE DAY.
ISOLATED SEVERE CONVECTION COULD BE FOUND THROUGH THE INTERSTATE
70 CORRIDOR, WESTWARD TO SCOTT CITY LATE IN THE AFTERNOON
THURSDAY, BUT WIDESPREAD SEVERE IS NOT ANTICIPATED. THE NAM MODEL
IS INDICATING THE WARMEST TEMPERATURES AROUND 100 DEGREES, WHILST
MOST OTHER NUMERICAL OUTPUT IS INDICATING LOW 90S. TEMPERATURES
SHOULD WARM TO SOMEWHERE IN THE MIDDLE THURSDAY AFTERNOON ACROSS
SOUTHWEST AND CENTRAL KANSAS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 302 PM CDT WED JUN 13 2012
THE EXTENDED PERIOD BEGINNING FRIDAY WILL SEE ONE UPPER SHORT WAVE
EXITING THE WESTERN PLAINS OF KANSAS, BRINGING ABOUT A 40 TO 50
PERCENT CHANCE OF THUNDERSTORMS NEAR THE I-70 CORRIDOR AND
NORTHWARD, EARLY THURSDAY NIGHT. AFTER MIDNIGHT THURSDAY, THE
PRECIP CHANCES WILL CHANGE TO 30 TO 40 PERCENT, AND ONLY IN TREGO,
ELLIS AND RUSH COUNTIES. THE NAM MODEL IS HINTING AT QPF FROM 0.60
TO 0.80-INCH IN OUR NORTHWEST FROM HAYS TO SCOTT CITY, BUT HAVE A
HARD TIME BUYING THAT MUCH PERCEPTIBLE WATER WILL FALL OUT, BASED
ON RECENT TRENDS. TRIMMED THURSDAY NIGHT QPF TO AROUND 0.25 TO
0.30-INCH. AS THAT SHORT WAVE EXITS, ANOTHER SMALL SCALE WAVE IS
EJECTED FROM THE LARGE UPPER LOW OFF THE COAST OF BAJA CALIFORNIA.
THIS SECOND WAVE IS LESS ORGANIZED THAN THE FIRST, AND WILL BRING
THUNDERSTORM CHANCES TO THAT AREA NORTH OF A LINE FROM JOHNSON
CITY TO LA CROSSE. THE UPPER BAJA LOW CUTS OFF SATURDAY NIGHT PER
THE ECMWF AND GFS MODELS, AND AN UPPER HIGH BEGINS TO BUILD OVER
TEXAS. FOR NOW, PLAN TO KEEP SUNDAY AND SUNDAY NIGHT FREE OF
PRECIPITATION CHANCES, BUT OUR EXTREME EAST WILL HAVE A SLIGHT
CHANCE MONDAY AFTERNOON AS UPPER DIVERGENCE WILL BE OVERHEAD, AND
A DOWN SLOPE FLOW WILL BE EVOLVING. A COLD FRONT WILL SINK INTO
SOUTHWEST KANSAS MONDAY NIGHT, AND THERE COULD BE A FEW SCATTERED
STORMS IN OUR SOUTHEAST ZONES WHERE THE GREATEST MOISTURE WILL BE,
SUCH AS SOUTHEAST OF LINE FORM LARNED TO DODGE CITY TO ASHLAND
MONDAY NIGHT. THE CR-EXTENDED BLEND PROCEDURE PLACED 30 POPS IN
MY EXTREME THREE EASTERN COUNTIES OF STAFFORD, PRATT AND BARBER
WEDNESDAY, OR DAY 7. KNOCKED THOSE POPS DOWN TO 20 PERCENT, AS THE
TIMING AND PLACEMENT OF THE NEXT WAVE COULD BE JUST ABOUT ANYWHERE
AROUND THAT TIME.
TEMPERATURES WILL BE RELATIVELY HOT DURING THE EXTENDED. OVERNIGHT
MINIMUM TEMPERATURES WILL GENERALLY BE IN THE MID 60S TO LOWER 70S
(SE, PRATT AND BARBER COUNTIES), WITH PERHAPS MONDAY NIGHT/TUESDAY
MORNING THE COOLEST MORNING WITH MIN TEMPS FROM THE LOWER 60S IN
SCOTT CITY TO 70 DEGREES IN MEDICINE LODGE. MAXIMUM TEMPERATURES
WILL START OUT FRIDAY IN THE LOWER 90S NORTH OF I-70 AND RANGE TO
THE MID 90S ALONG THE OKLAHOMA BORDER. BY SUNDAY, MAXIMUM
TEMPERATURES WILL BE IN THE LOWER TO MID 90S ACROSS ALL OF SOUTHWEST
KANSAS, THEN WARM TO PERHAPS THE WARMEST DAY MONDAY. HIGHS MONDAY
SHOULD TOP OUT IN THE MID TO UPPER 90S, WITH THE ELKHART AREA
BEING NEAR THE CENTURY MARK. THE WEAK COLD FRONT WILL SLIP THROUGH
MONDAY NIGHT (BEST GUESS), AND KNOCK HIGHS DOWN A NOTCH INTO THE
LOWER TO MID 90S BOTH TUESDAY AND WEDNESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1257 PM CDT WED JUN 13 2012
A NARROW STRIP OF MID LEVEL (9-10KFT) LEVEL ACCAS WAS NOTED ON
VISIBLE SATELLITE BETWEEN KDDC AND KHYS. OTHER THAN THIS STRIP OF
CLOUDS, THE SKY WAS CLEAR ACROSS THE AREA. MID LEVEL INSTABILITY MAY
ALLOW ADDITIONAL CLOUDS TO DEVELOP THROUGH THE AFTERNOON ON THE MID
LAYERS, AND VERY SMALL CONVECTIVE CHANCES ARE ANTICIPATED FOR THE
EVENING (AFTER 00 UTC PERIOD). AND STORMS THAT MIGHT DEVELOP WILL
PROBABLY BE HIGH BASED AND ONLY MAY AFFECT THE KGCK TERMINAL.
CONFIDENCE IS LOW ENOUGH HOWEVER TO NOT MENTION AT THIS TIME IN THE
KGCK TERMINAL AT THIS TIME.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 67 96 70 93 / 20 20 20 20
GCK 68 97 70 93 / 20 20 30 20
EHA 67 96 69 91 / 20 20 20 20
LBL 68 96 71 93 / 20 10 20 20
HYS 68 97 68 90 / 20 30 50 20
P28 68 95 76 94 / 20 20 20 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RUSSELL
SHORT TERM...RUSSELL
LONG TERM...BURKE
AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
627 PM EDT WED JUN 13 2012
.SYNOPSIS...
HIGH PRESSURE WILL BRING DRY AND COOL AIR OVER THE UPPER OHIO VALLEY
OVERNIGHT THROUGH THE END OF THE WEEK. THE STRETCH OF NICE
WEATHER WILL CONTINUE THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH THURSDAY/...
AN EARLY EVENING ENHANCED SHORT TERM FORECAST UPDATE HAS BEEN
ISSUED WITH LITTLE CHANGE OTHER THAN TO INCREASE SKY GRIDS SLIGHTLY
OVERNIGHT AS CIRRUS PASSES OVER THE AREA.
THE LATEST RAP MID-LEVEL ANALYSIS INDICATES A 500MB RIDGE AXIS
CENTERED ACROSS THE UPPER OHIO VALLEY WITH A DEEP LAYER OF DRY AIR
IN PLACE. AT THE SURFACE, HIGH PRESSURE IS CENTERED ACROSS
MICHIGAN. IN THIS PATTERN, SKIES ARE CLEAR WITH LIGHT AND NORTHERLY
WINDS ACROSS THE AREA.
THE MID-LEVEL RIDGE AXIS WILL SLOWLY NUDGE EASTWARD OVERNIGHT WITH
THE HIGH SHIFTING INTO EASTERN CANADA ON THURSDAY. THE DRY PROFILE
ALOFT WILL REMAIN IN PLACE ASIDE FROM SOME THIN CIRRUS CROSSING
THE AREA OVERNIGHT. CIRRUS WILL PASS ON THURSDAY, WITH ANOTHER
CLEAR DAY EXPECTED ACROSS THE AREA. DESPITE THIN CIRRUS CROSSING
THE AREA, A STRONG RADIATIONAL COOLING NIGHT IS EXPECTED. OVERNIGHT
LOWS ARE CLOSER TO THE WARMER MET GUIDANCE, RANGING FROM THE UPPER
40S TO LOWER 50S. WITH 850 TEMPS WARMING TO 11-13C TOMORROW AND
ABUNDANT SUNSHINE, HIGHS WILL WARM TO NEAR NORMAL SEASONAL VALUES.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY/...
STRONG SURFACE HIGH TONIGHT WILL STAY OVER THE GREAT LAKES AND
BRING LIGHT NORTH WINDS TO THE REGION. RADITIONAL COOLING WILL
BRING TEMPERATURES DOWN TO THE 50S AND 40S.
SURFACE HIGH AND STRENGTHENING EASTERN RIDGE WILL ALLOW FOR
COMFORTABLE CONDITIONS AND PLENTY OF SUNSHINE THROUGH THE REST OF
THE PERIOD. NEAR NORMAL TEMPS THURSDAY THROUGH SATURDAY WITH JUST
A COUPLE OF DEGREES ABOVE THE NORMAL HIGH.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
SATURDAY NIGHT THROUGH WEDNESDAY...MODEL AGREEMENT IS RATHER
STRONG WITH REGARD TO THE DEVELOPMENT AND AMPLIFICATION OF AN
UPPER RIDGE OVER THE EASTERN THIRD OF THE U.S. THROUGH THE
EXTENDED FORECAST PERIOD. RUN-TO-RUN MODEL VARIATION HAS BEEN
VIRTUALLY NIL...AND OTHER THAN A POSSIBLE IMPULSE RUNNING OVER
THE RIDGE AXIS...THE CHANCES FOR PRECIPITATION THROUGHOUT THE
EXTENDED FORECAST ARE FAIRLY LOW.
WITH SURFACE HIGH PRESSURE IN CONTROL AND AN UPPER RIDGE AXIS
TRANSITING THE AREA...COMPRESSIONAL WARMING AND INCREASING MIXING
BEYOND NEXT WEEKEND WILL ALLOW TEMPERATURES TO SURGE WELL ABOVE
NORMAL. AS MODEL CONSENSUS 850 MB TEMPERATURES RUN FROM ROUGHLY
16C UP TOWARD 20C...THE POSSIBILITY OF ECLIPSING 90F IN SOME
LOCATIONS INCREASES DAY-BY-DAY THROUGH THE MIDDLE OF NEXT WEEK. AT
THIS TIME...THE RIDGE BREAKDOWN FOR OUR AREA STILL SEEMS TO BE FAR
ENOUGH OUT INTO THE FUTURE TO BE BEYOND THE FORECAST
PERIOD...HOWEVER THE ECMWF BECOMES SOMEWHAT FLATTER BY THE MIDDLE
OF NEXT WEEK SUCH THAT A FEW SHOWERS OR THUNDERSTORMS IN AFTERNOON
INSTABILITY CANNOT BE RULED OUT...PARTICULARLY NORTH OF
PITTSBURGH. HOWEVER...ALL THINGS CONSIDERED...A DRY SUMMERLIKE
PATTERN LOOKS TO CONTINUE FOR THE EASTERN THIRD OF THE COUNTRY.
FRIES
&&
.AVIATION /22Z WEDNESDAY THROUGH MONDAY/...
HIGH PRESSURE WILL TRANSIT THE GREAT LAKES...LEAVING OUR AREA TO
ITS SOUTH OVER THE NEXT 24-30 HOURS. OVERNIGHT INVERSIONS SHOULD
FORM AND ALLOW LIGHT/VARIABLE WINDS EVERYWHERE...HOWEVER AS
DAYTIME THURSDAY ENSUES...WINDS SHOULD TURN LIGHT EASTERLY FOR US
AROUND THE SOUTH SIDE OF THE SURFACE HIGH. SKIES SHOULD REMAIN
MOSTLY CLEAR WITH ONLY AN OUTSIDE SHOT AT SOME CIRRUS...SO VFR
CONDITIONS WILL BE THE RULE.
.OUTLOOK...WEDNESDAY NIGHT THROUGH SUNDAY...
HIGH PRESSURE WILL ALLOW FOR VFR CONDITIONS TO PREVAIL ACROSS THE
TERMINALS THROUGH SUNDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
102 PM CDT WED JUN 13 2012
.AVIATION...18Z TAFS FOR KOMA...KLNK AND KOFK. VFR TO MVFR
CONDITIONS THROUGH THE FORECAST PERIOD. THERE IS A SLIGHT CHANCE
OF -TSRA PRIMARILY AT KOFK IN THE 03Z TO 06Z TIME FRAME. OTHERWISE
THE WEATHER FEATURE WILL BE THE BREEZY SOUTHEAST WINDS 10 TO 15
KTS WITH GUSTS 25 TO 28KTS UNTIL 01Z. COLD FRONT WILL APPROACH THE
FORECAST AREA PRODUCING THREAT OF TSRA...ESPECIALLY KOFK
AREA...BY THE END OF THE FORECAST PERIOD.
&&
.PREV DISCUSSION... /ISSUED 614 AM CDT WED JUN 13 2012/
88D MOSAIC THIS MORNING SHOWING NARROW LINE OF BOWED-OUT ELEVATED
CONVECTION DRIVING EWD INTO ERN SD/ERN NEB. ACTIVITY WAS OCCURRING
WITHIN AREA OF STRONG LAYER DIFFERENTIAL DIVG/850MB WAA WITH A
LLVL MOIST FEED UP THRU THE CNTRL PLAINS. HRRR AND RAP SUGGESTING
ACTIVITY SHOULD BE OUT OF THE CWA SOMETIME AROUND RUSH HOUR.
ON THE WHOLE...MODELS CONTINUE TO BE IN REASONABLY GOOD AGREEMENT
THAT LARGE SCALE FLOW OVER THE NEXT WEEK WILL TRANSITION FROM NEAR
ZONAL OVER THE CONUS TO A RELATIVELY STAGNANT SITUATION WITH A BROAD
TROF COVERING THE WRN CONUS AND A RIDGE TO THE EAST. ALSO GOOD
AGREEMENT THAT BULK OF ACCUMULATING PCPN WILL GENERALLY OCCUR OVER
THE UPPER MIDWEST...ERN DAKOTAS...WRN IA...ERN NEB THRU DAY 7. ALL
THIS IN PART TO A PROLONGED MID LYR BNDRY ORIENTED PARALLEL TO SW-NE
FLOW ALOFT WITH SUSTAINED LLVL MOISTURE TO FEED ON PER MOISTURE
TRANSPORT PROGS. LIFTING MECHANISM THOUGH WILL BE MEANDERING SOMEWHAT
DURING THIS TIME...MAKING IT IMPOSSIBLE TO PIN DOWN POPS WITHIN THE
CWA. THUS...BECAUSE OF UNCERTAINTIES WILL OPT TO JUST BLANKET THE
AREA WITH SMALL POPS.
DEE
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1252 PM EDT WED JUN 13 2012
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE NORTH AND MOVE ACROSS THE AREA
THIS EVENING. SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
REDEVELOP ACROSS THE EASTERN CAROLINAS THIS AFTERNOON...WITH THE
BEST CHANCE ALONG THE COAST. HIGH PRESSURE WILL BUILD IN LATE
TONIGHT AND THURSDAY...BRINGING A RELATIVELY COOL AND DRY PATTERN
WHICH WILL PERSIST INTO NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 100 PM WEDNESDAY...NORTHERLY SURFACE WINDS ARE WELL-
ESTABLISHED...BUT LOW-LEVEL MOISTURE IS HANGING TOUGH WITH DEWPOINTS
STILL WITHIN A FEW DEGREES OF 70 THROUGHOUT THE AREA. AN AREA OF
ENHANCED CUMULUS MOVING SOUTHWARD ACROSS EAST-CENTRAL NC IS
ASSOCIATED WITH THE ACTUAL SURFACE COLD FRONT. CONVECTION MAY FIRE
ALONG THIS FEATURE STARTING WITHIN THE NEXT 90 MINUTES. WE`VE
TWEAKED HIGH TEMPERATURES UPWARD BASED ON LATEST OBSERVATIONS...
ESPECIALLY NEAR THE COAST. OTHER CHANGES WERE MINOR. PREVIOUS
DISCUSSION FROM 10 AM FOLLOWS...
SURFACE WINDS HAVE SHIFTED NORTHWESTERLY ALL THE WAY DOWN TO THE
BEACHES THIS MORNING AS A SURFACE TROUGH HAS PUSHED OFF THE COAST.
THE ACTUAL SURFACE COLD FRONT IS LAGGING THIS WIND SHIFT AND SHOULD
MAKE IT OFFSHORE EARLY THIS EVENING. WE`RE LOSING THE DEEP TROPICAL
MOISTURE AS MID-LEVEL WINDS HAVE SHIFTED NORTHWESTERLY BEHIND A
DEPARTING UPPER LEVEL TROUGH. PRECIPITABLE WATER VALUES (CURRENTLY
1.75 INCHES) SHOULD FALL THROUGHOUT THE DAY AND INTO TONIGHT AS
DRIER AIR BUILDS IN MAINLY AT AND ABOVE 700 MB.
WITH MANY MORE BREAKS EXPECTED IN LOW AND MID-LEVEL CLOUD COVER
TODAY COMPARED TO THE PAST SEVERAL DAYS HIGH TEMPERATURES SHOULD
MAKE IT INTO THE 80S EVERYWHERE...WITH SOME UPPER 80S EVEN POSSIBLE
NEAR AND WEST OF LUMBERTON...DILLON AND FLORENCE. THIS WILL STEEPEN
LOW-LEVEL LAPSE RATES SIGNIFICANTLY AND SHOULD CREATE SCATTERED
SHOWERS AND STORMS THIS AFTERNOON. LATEST HRRR MODEL RUNS SHOW WE
SHOULD EXCEED CONVECTIVE TRIGGER TEMPERATURE BETWEEN 17-18Z...1-2 PM
EDT. LOWER PRECIP WATER VALUES WILL NOT BE ABLE TO COMPLETELY NEGATE
THE THREAT OF MORE HEAVY RAINFALL AND ISOLATED FLOODING DUE TO SLOW
CELL MOTION EXPECTED TO BE FROM NORTH TO SOUTH AT ONLY 10-12 MPH.
THERE WILL ALSO BE A THREAT OF GUSTY WINDS AS DRIER AIR ALOFT IS
ENTRAINED INTO THE STORM CELLS WITH DCAPE VALUES INCREASING TO 1000
J/KG OR MORE.
CONVECTIVE ACTIVITY SHOULD END FROM NORTH TO SOUTH THIS EVENING AS
THE ACTUAL COLD FRONT PUSHES OFFSHORE AND DRIER MORE STABLE AIR
BUILDS IN.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...MAIN FORECAST CHALLENGE FOR THE SHORT TERM
WILL BE TEMPERATURES AS MOISTURE WILL BE ON THE DECREASE AS AN OMEGA
CONFIGURATION DEVELOPS AT THE MID LEVELS. AT THE SURFACE A
FORMIDABLE NORTHEAST FLOW WILL DEVELOP AS HIGH PRESSURE BUILDS DOWN
FROM THE NORTHEAST AND LOW PRESSURE MEANDERS NEAR BERMUDA. MET
GUIDANCE IS QUITE A BIT WARMER AS OPPOSED TO THE MAV NUMBERS THROUGH
THE PERIOD MORE-SO THURSDAY. THIS APPEARS TO BE A FUNCTION OF
LINGERING LOW LEVEL MOISTURE VIA THE GFS. NUMBERS JOG TOWARD
SLIGHTLY BETTER AGREEMENT FRIDAY. HAVE LEANED TOWARD THE COOLER MAV
NUMBERS OPTING FOR A SLOWER PROGRESSION OF THE LOW LEVEL MOISTURE.
NO POPS THROUGH THE PERIOD.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 3 AM WEDNESDAY...NO SIGNIFICANT CHANGES TO THE MEDIUM RANGE
GUIDANCE THIS MORNING AS THE FORECAST AREA CONTINUES TO BE SITUATED
IN THE EASTERN PART OF A MID LEVEL OMEGA PATTERN FOR MOST OF THE
PERIOD. I DID INCREASE THE POPS INCREMENTALLY SUNDAY AND MONDAY TO
SLIGHT CHANCE TO MATCH HPC AND ADJACENT OFFICES VIA NORTHEAST
RESULTANT SEA BREEZE COMBINED WITH THE 700MB SUBSIDENCE INVERSION
ABATING. THE PATTERN BEGINS TO CHANGE LATE IN THE PERIOD WITH THE
GFS ADVERTISING A REX BLOCK DEVELOPING SO CONFIDENCE IS BELOW
AVERAGE. NO CHANGES TO TEMPERATURE FORECAST.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 18Z...ENHANCED CUMULUS VISIBLE ON SATELLITE DROPPING SOUTHWARD
FROM EAST-CENTRAL NORTH CAROLINA ALONG AT LEAST TWO FRONTAL-LIKE
BOUNDARIES. EXPECT SCATTERED CONVECTION TO FIRE ALONG THESE
BOUNDARIES...MAINLY BETWEEN 19-23Z. COVERAGE WILL BE ABOUT 50
PERCENT OF THE AREA. AFTER SUNSET MODELS ARE SHOWING QUITE A BIT OF
ATLANTIC STRATOCUMULUS ADVECTING SOUTHWESTWARD AS SFC LOW PRESSURE
DEVELOPS WELL OFFSHORE. THESE CLOUD BASES COULD LOWER TO MVFR
OVERNIGHT. WILL KEEP THINGS VFR AT THIS TIME BUT CONFIDENCE IS NOT
HIGH. THURSDAY...PREDOMINANTLY VFR WITH CONTINUED NORTHEAST FLOW.
EXTENDED OUTLOOK...MAINLY VFR THROUGH THE FORECAST PERIOD.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 100 PM WEDNESDAY...NO SIGNIFICANT CHANGES TO THE MARINE
FORECAST WITH THIS EARLY AFTERNOON NEAR-TERM UPDATE. PREVIOUS
DISCUSSION FROM 10 AM FOLLOWS...
THUNDERSTORM ACTIVITY HAS PUSHED WELL OFFSHORE AND INTO THE GULF
STREAM...WITH LIGHTER SHOWERS NOW ENDING ACROSS THE COASTAL WATERS.
THERE SHOULD BE A LULL IN CONVECTION LASTING THROUGH EARLY AFTERNOON
BEFORE ADDITIONAL SHOWERS AND THUNDERSTORMS DEVELOPING INLAND BEGIN
TO MOVE OFFSHORE...AFFECTING THE COASTAL WATERS THROUGH THIS
EVENING. WINDS HAVE SHIFTED TO THE WEST OR NORTHWEST THIS MORNING AS
A TROUGH HAS PUSHED OFF THE COAST. THE ACTUAL SURFACE COLD FRONT IS
STILL WELL INLAND AND SHOULD WAIT UNTIL THIS EVENING TO PUSH OFF THE
COAST.
SEAS CURRENTLY RANGE FROM 2-3 FT NEAR THE COAST...BUT EARLIER
SHOWER/STORM ACTIVITY HAS BUILT SEAS TO AROUND 5 FT AT THE FRYING
PAN SHOALS BUOY AND AT THE OFFSHORE LEJEUNE BUOY. SEA HEIGHTS SHOULD
DIMINISH THROUGH EARLY EVENING...BUT MAY BEGIN TO BUILD LATER
TONIGHT AS INCREASING NORTHEAST WINDS DEVELOP BEHIND THE ACTUAL COLD
FRONT.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...A NORTHEASTERLY FLOW WILL PREVAIL
THROUGHOUT THE PERIOD AS HIGH PRESSURE BUILDS DOWN FROM THE
NORTHEAST AND LOW PRESSURE SLOWLY DEVELOPS WELL INTO THE ATLANTIC.
STRONGEST WINDS OCCUR LATE FRIDAY WHEN THE 20-25 KNOT RANGE WILL
LIKELY BE CLOSER TO THE HIGH END OF THE RANGE. THE PERSISTENT FETCH
WILL ALLOW SEAS TO BUILD LATE THURSDAY TO ECLIPSE THE SIX FOOT SMALL
CRAFT CRITERIA AND CONTINUE THROUGH THE REMAINDER OF THE PERIOD.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3 AM WEDNESDAY...ESSENTIALLY NO CHANGES TO THE EXTENDED
COASTAL WATERS FORECAST AS A NORTHEASTERLY FLOW SHOULD PREVAIL. MAY
SEE MORE VEERING SUNDAY AFTERNOON AS THE FLOW IS LIGHTER ALLOWING
MORE OF A NORTHEAST RESULTANT TO DEVELOP. THE CAVEAT WITH THIS TYPE
OF SCENARIO ARE THE EMBEDDED SURGES. I DID WALK BACK SEAS SLIGHTLY
BUT A SMALL CRAFT ADVISORY MAY STILL BE NEEDED BUT IT APPEARS MORE
MARGINAL AT THIS POINT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...DL/TRA
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
310 PM CDT WED JUN 13 2012
.SHORT TERM...
CONVECTION CHANCES THROUGHOUT THE PERIOD...INCLUDING THE
POSSIBILITY OF SEVERE LATE TONIGHT...WILL BE THE PRIMARY FORECAST
HEADACHE FOR THE SHORT TERM.
WV LOOP SHOWS THE SHORTWAVE TROUGH THAT BROUGHT SHOWERS TO CENTRAL
MN DURING THE DAY TODAY HEADING OFF TO THE EAST...WITH THE NEXT
SHORTWAVE OVER MT. VIS SAT LOOP HAS SOME FAIRLY VIGOROUS TOWERING
CU OVER THE WESTERN CWA...WHICH FITS WITH MODEL SOUNDINGS SHOWING
AROUND 800 J/KG AND NOT MUCH CAP. HOWEVER...DEVELOPMENT OF ECHOES
ON RADAR HAS NOT REALLY BEEN HAPPENING...AND SPC MESOANALYSIS HAS
THE BEST CAPE FURTHER NORTH AND WEST. HRRR HAS SOME BLIPS IN OUR
SOUTHWESTERN COUNTIES DURING THE LATE AFTERNOON AND EVENING...BUT
QUICKLY DISAPPEARING AND MOST OF THE ACTIVITY COMING IN LATER
TONIGHT AS THE MAIN SHORTWAVE COMES EAST. WILL KEEP AN EYE ON
SATELLITE/RADAR TRENDS...BUT MAY HAVE TO INCLUDE SOME LOW POPS FOR
OUR SOUTHWESTERN COUNTIES IN CASE SOMETHING CAN GET GOING THIS
EVENING.
ALL MODELS ARE IN FAIRLY GOOD AGREEMENT ON DEVELOPING STORMS OUT
IN THE WESTERN DAKOTAS WHERE THE BEST INSTABILITY CURRENTLY
IS...AND BRINGING SOMETHING EASTWARD INTO THE CWA BY MORNING.
THERE IS A FAIR AMOUNT OF ELEVATED CAPE OVER THE SOUTHWESTERN
COUNTIES BY 12Z...AND DEEP LAYER BULK SHEAR INCREASES INTO THE 60
TO 70 KT RANGE. THINK THAT THE PRECIP COULD COME EASTWARD AS A
POSSIBLY SEVERE MCS AFTER MIDNIGHT TONIGHT. INCREASED POPS TO 70
PERCENT OVER OUR SOUTHEASTERN COUNTIES...AND PUT IN A SEVERE
MENTION. WITH PWATS GETTING UP TO AROUND 1.5 INCHES...HEAVY RAIN
COULD BE A POSSIBILITY.
THE UPPER TROUGH WILL MOVE OFF INTO SOUTHERN MANITOBA
TOMORROW...PUSHING THE SFC TROUGH AXIS EASTWARD THROUGH THE CWA.
THUNDERSTORM ACTIVITY SHOULD PUSH EASTWARD AND BE MOSTLY IN MN BY
TOMORROW AFTERNOON. WILL CONTINUE TO HAVE TO WATCH FOR SEVERE
TOMORROW AFTERNOON AS MODELS CONTINUE TO SHOW A GOOD AMOUNT OF
CAPE ABOVE 1500 J/KG AND BULK SHEAR OVER 50 KTS. JUST INCLUDED
LIKELY POPS MENTION THOUGH AND LEFT SEVERE MENTION OUT FOR NOW.
THURSDAY NIGHT AND FRIDAY SHOULD BE FAIRLY QUIET AS WE SEE
SOUTHWESTERLY FLOW ALOFT BETWEEN SYSTEMS. SFC PATTERN WILL BE
FAIRLY WEAK...WITH ANOTHER TROUGH NOT COMING IN UNTIL THE NEXT
SYSTEM STARTS APPROACHING FRIDAY NIGHT. MODELS SHOW SOME
DIFFERENCES IN TIMING ON THE NEXT SHORTWAVE...WITH THE NAM MOST
PROGRESSIVE ON BRINGING THE TROUGH OUT INTO THE PLAINS. LEANED
TOWARDS THE SLOWER GFS AND ECMWF. CONTINUED TO KEEP POPS IN THE
50-70 PERCENT RANGE FOR LATE FRIDAY NIGHT INTO SATURDAY.
TEMPERATURES WILL CONTINUE TO BE FAIRLY WARM...PARTICULARLY FRIDAY
AS BOTH THE NAM AND GFS HAVE 850MB TEMPS APPROACHING 20 C IN THE
SOUTHERN RED RIVER VALLEY. CONTINUED TO KEEP HIGHS IN THE UPPER
70S TO LOW 80S...WITH SOME SLIGHTLY COOLER TEMPS SATURDAY
AFTERNOON. LOWS WILL BE MAINLY IN THE UPPER 50S AND 60S.
.LONG TERM... /SAT NIGHT THROUGH WED/
UPPER WAVE/LOW OVER SOUTH CNTRL CANADA WILL RESULT
IN A SERIES OF WAVES MOVING ACROSS THE NORTHERN TIER...
RESULTING IN A CHANCE OF TSTMS OR SHOWERS THROUGHOUT
THE MAJORITY OF THE PERIOD. BEST CHANCE TO NOT SEE ACTIVITY
WILL BE SAT NIGHT...AS UPPER WAVE EXITS EASTERN ZONES AND
SUBSIDENCE SETS IN. SUN MORNING SHOULD BE DRY AS WELL...BEFORE
THE POTENTIAL FOR CONVECTION INCREASES AGAIN BY SUN AFTN. TEMPS
WILL GENERALLY BE IN THE 70S AS THE PERIOD WILL BE RATHER CLOUDY.
&&
.AVIATION...
CU FIELD WILL SPREAD SOUTH TO NORTH THROUGHOUT THE AFTERNOON AND
INTO THE EVENING...BUT SHOULD DISSIPATE AFTER SUNSET. MAY SEE SOME
BREAKS IN CLOUDS TONIGHT...BUT MID LEVEL DECK WILL PUSH INTO AREA
OVER NIGHT. EXPECT TO SEE SOME SHOWERS AND THUNDERSTORM ACTIVITY
FROM THE SOUTHERN VALLEY THROUGH THE BJI AREA....AND MORE ISOLATED
ACTIVITY AT GFK...TVF AND DVL.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
JR/SPEICHER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
257 PM CDT WED JUN 13 2012
.SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT...
MAIN FORECAST PROBLEM IS THUNDERSTORM CHANCES TONIGHT.
CURRENTLY...SURFACE LOW PRESSURE IS SITUATED OVER SOUTHEAST
MONTANA WITH SOUTHERLY FLOW ACROSS WESTERN AND CENTRAL NORTH
DAKOTA. SHORTWAVE LIFTING FROM NORTHERN MONTANA IN TO SOUTHERN
SASKATCHEWAN IN PRODUCING A BAND OF SHOWERS THAT IS LIFTING ACROSS
NORTHWEST NORTH DAKOTA. MOISTURE CONTINUES TO INCREASE OVER THE
REGION WITH DEWPOINTS CURRENTLY IN THE MID 50S.
MODELS INDICATE SCATTERED CONVECTION DEVELOPING ALONG THE EASTERN
MONTANA COLD FRONT AS IT PUSHES INTO WESTERN NORTH DAKOTA. THE
ONGOING CONVECTION IN THE NORTHWEST MAY ACTUALLY INHIBIT
DESTABILIZATION...BUT WEST CENTRAL AND SOUTHWEST NORTH DAKOTA WILL
SEE MORE SUN THIS AFTERNOON WHICH SHOULD HELP LOWER CONVECTIVE
INHIBITION. CONVECTION WILL HAVE A SLIGHT TO MODERATELY UNSTABLE
ATMOSPHERE TO WORK WITH INITIALLY WITH DECENT 0-6KM SHEAR. IN
ADDITION...INCREASING LOW LEVEL MOISTURE IS NOT UNDERDONE BY
FORECAST MODELS. AS CONVECTION TRACKS INTO CENTRAL NORTH DAKOTA
SHEAR AND CAPE REMAIN BUT THE CAP STRENGTHENS AS YOU MOVE EAST
FROM BISMARCK TO JAMESTOWN. HIGH RESOLUTION MODELS SEEM TO HIT ON
THIS WITH THIS INITIAL CONVECTION HAVING A HARD TIME HOLDING
TOGETHER AS IT MOVES INTO CENTRAL NORTH DAKOTA.
A STRONG SHORTWAVE MOVING THROUGH WESTERN MONTANA THIS AFTERNOON
WILL BE THE TRIGGER FOR EITHER ADDITIONAL THUNDERSTORM
DEVELOPMENT THIS EVENING OR A STRENGTHENING OF CONVECTION THAT
DEVELOPS THIS AFTERNOON ALONG THE EASTERN MT COLD FRONT. THE
LATEST HRRR INDICATES CONVECTION DEVELOPING OVER THE NORTHERN HIGH
PLAINS AND MOVING INTO THE WESTERN DAKOTAS BY MID EVENING AND
TRACKING ACROSS THE LOCAL AREA LATE THIS EVENING AND OVERNIGHT.
EML ADVECTING INTO THE REGION WILL MAINTAIN STEEP LAPSE RATES OVER
THE FORECAST AREA TONIGHT. THIS CONVECTION MAY INITIALLY FORM AS
DISCRETE SUPERCELLS BUT THEN DEVELOP INTO A LINEAR CONVECTIVE
SYSTEM AS IT TRAVERSES THE AREA TONIGHT. ALTHOUGH A TORNADIC
SUPERCELL CANNOT BE RULED OUT LATE THIS AFTERNOON OR THIS
EVENING...THE MAIN THREAT OVERNIGHT WOULD BE LARGE HAIL AND
DAMAGING WINDS. WITH PWATS INCREASING WELL ABOVE NORMAL...HEAVY
RAIN CAN ALSO BE EXPECTED...ESPECIALLY FROM FROM THE FAR SOUTH
CENTRAL INTO THE JAMES RIVER VALLEY. THIS AREA HAS NOT SEEN
SIGNIFICANT RAINFALL LATELY AND THE PROGRESSIVE NATURE OF THE
SYSTEM...WILL NOT ISSUE ANY HYDRO HEADLINES.
PRECIPITATION MAY BE LINGERING IN THE FAR EAST ON THURSDAY
MORNING. OTHERWISE THE MAJORITY OF THE DAY WILL BE DRY ACROSS THE
SOUTHERN TWO THIRDS OF THE CWA. THE FAR NORTH WILL SEE A CHANCE OF
SHOWERS AS THE UPPER LOW TRACKS ACROSS SOUTHERN CANADA. THE SHORT
LIVED DRY SPELL SHOULD CONTINUE THROUGH THURSDAY NIGHT WITH UPPER
LEVEL RIDGING OVER THE LOCAL AREA AHEAD OF THE NEXT SYSTEM.
.LONG TERM...FRIDAY THROUGH NEXT WEDNESDAY...
POTENT UPPER LEVEL WAVE/MID LEVEL CLOSED LOW WILL LIFT ACROSS THE
ROCKIES AND THROUGH THE NORTHERN PLAINS FRIDAY-SATURDAY BRINGING
LIKELY SHOWERS AND THUNDERSTORMS TO MOST LOCATIONS. UNCERTAIN IF WE
WILL SEE WIDESPREAD SEVERE WEATHER THOUGH WITH DAYTIME HEATING ON
FRIDAY LIMITED ALONG WITH MARGINAL CAPE. SCALED BACK CONSIDERABLY ON
POPS SATURDAY AFTERNOON WITH DRY AIR PUNCHING INTO THE REGION FROM
SOUTHWEST TO CENTRAL. LEFT CHANCES IN EAST FOR LINGERING
SHOWERS/THUNDER...AND CHANCES ACROSS THE NORTH NEAR THE TRACK OF THE
MID LEVEL LOW.
DRY CONDITIONS REGION WIDE SATURDAY NIGHT WITH A WEAK RIDGE PUSHING
ACROSS THE NORTHERN PLAINS. AFTERWARDS (SUN-WED)...OUR WEATHER
PATTERN RETURNS TO VERY ACTIVE AS THE UPPER LEVEL JET BECOMES
ORIENTATED OVER THE NORTHERN CONUS AND STEERS SEVERAL MID LEVEL
DISTURBANCES FROM ACROSS THE ROCKIES INTO THE NORTHERN PLAINS.
SHOULD SEE A GOOD CHANCE FOR PRECIPITATION EACH PERIOD.
TEMPERATURES WILL AVERAGE NEAR NORMAL THROUGH THIS
WEEKEND...TRENDING TO NEAR TO SLIGHTLY BELOW NORMAL MON-WED.
&&
.AVIATION...
AN AREA OF SURFACE LOW PRESSURE ACCOMPANIED BY AN UPPER LEVEL
SHORTWAVE WILL COMBINE WITH INCREASINGLY UNSTABLE CONDITIONS TO
BRING THUNDERSTORMS TO WESTERN INTO CENTRAL NORTH DAKOTA THIS
AFTERNOON AND EVENING. MENTIONED VCTS GROUPS FOR ALL BUT KJMS.
HEAVIER THUNDERSTORMS ARE POSSIBLE LATER THIS EVENING AND OVERNIGHT
BEFORE 10Z MAINLY FOR KDIK...KBIS...AND KJMS. WHILE VFR CONDITIONS
SHOULD PREVAIL FOR THE MAJORITY OF THE PERIOD...MVFR-IFR CONDITIONS
CAN BE EXPECTED WITH ANY THUNDERSTORMS WHICH PASS OVER TERMINALS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...TWH
LONG TERM/AVIATION...NH
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
559 PM CDT WED JUN 13 2012
.DISCUSSION...
SEE 00Z AVIATION DISCUSSION BELOW.
&&
.AVIATION...
VFR CONDITIONS ARE EXPECTED THE NEXT 24 HOURS. WINDS WILL BE SOUTH
AT 10 TO 15 KNOTS WITH A FEW GUSTS TO 20 KNOTS. WATCHING A FEW
TSTMS OVER SOUTHWEST TEXAS. THIS ACTIVITY WILL PROBABLY REMAIN
WELL WEST OF THE TERMINALS.
21
&&
.PREV DISCUSSION... /ISSUED 348 PM CDT WED JUN 13 2012/
SHORT TERM...
WE HAD ISOLATED WEAK CONVECTION EARLY TODAY BUT THIS HAS SINCE
DISSIPATED. SKIES HAVE BECOME MOSTLY CLEAR TO PARTLY CLOUDY ACROSS
THE CWA LIKELY IN RESPONSE TO SUBSIDENCE IN THE WAKE OF THE
DEPARTING MCV ALONG THE RED RIVER VALLEY. A WEAK SURFACE...YET
DISCERNIBLE...BOUNDARY STILL EXISTS OVER THE SOUTHWEST CWA PER THE
KSJT WSR-88D BUT THIS FEATURE REMAINS BENIGN AT THIS TIME. LOOKING
WEST...MID LEVEL RADAR ECHOES HAVE BEEN INCREASING ACROSS
SOUTHWEST TX THIS AFTERNOON AHEAD OF AN APPROACHING SHORTWAVE. AS
THIS SYNOPTIC SCALE ASCENT OVERSPREADS THE AREA AND SURFACE TEMPS
WARM INTO THE MID/UPPER 90S...I ANTICIPATE CONVECTION DEVELOPING
IN THE VICINITY OF THE CWA. CONFIDENCE IS FAIRLY LOW THAT WE WILL
SEE WIDESPREAD THUNDERSTORMS BUT SEVERAL VERSIONS OF THE HIRES WRF
AND THE HRRR ALL AGREE IN THUNDERSTORMS FORMING OVER THE
CENTRAL/EASTERN COUNTIES.
A LOOK AT THE SPC MESO ANALYSIS PAGE DEPICTS SBCAPE VALUES ON THE
ORDER OF 2500-3500 J/KG WITH EFFECTIVE SHEAR VALUES BETWEEN 40-50
KTS. THE QUESTION WILL BE WHETHER OR NOT THE CAP WILL GIVE WAY.
THUS...WE DO HAVE A CONDITIONAL THREAT FOR SEVERE WEATHER BUT I AM
PLAYING THIS RATHER CONSERVATIVE FOR NOW THINKING THAT THE CAP
WILL HOLD FOR THE MOST PART AND ANY CONVECTIVE INITIATION WILL
LIKELY BE DELAYED UNTIL WELL AFTER PEAK HEATING. THUS...I AM ONLY
CARRYING 20 POPS FOR THE PERIOD BEGINNING AT 00Z. OVERNIGHT TEMPS
WILL FALL INTO THE LOWER 70S /BUT WILL LIKELY BE LOWER IF
CONVECTION DOES DEVELOP/.
GENERALLY DRY AND WARM CONDITIONS ARE EXPECTED FOR THURSDAY WITH
SOUTH WINDS INCREASING TO 10-20 MPH ACROSS THE CWA. HIGHS ARE
EXPECTED TO BE IN THE MID/UPPER 90S.
JOHNSON
LONG TERM...
THURSDAY NIGHT INTO FRIDAY...THE UPPER LEVEL LOW THAT IS
CURRENTLY OVER SOUTHERN CALIFORNIA TODAY WILL BE ENVELOPED BY
ANOTHER LOW THAT WILL MOVE SOUTH ALONG THE CALIFORNIA COAST. THERE
WILL BE AN UPPER LEVEL TROUGH OVER THE GULF COAST REGION AS WELL
WHILE WEST CENTRAL TEXAS WILL BE IN BETWEEN UNDERNEATH RIDGING.
FOR THIS REASON...WILL GO WITH TEMPERATURES SLIGHTLY WARMER THAN
GUIDANCE FOR FRIDAY AND SATURDAY. HAVE NOT EXPANDED ANY OF THE
INHERITED POPS FRIDAY AFTERNOON AND EVENING. IT STILL APPEARS THAT
THE LOW WILL BE TOO FAR WEST TO DIRECTLY INFLUENCE US...AND THAT
MOST OF THE CONVECTION WILL GET GOING IN THE HIGHER TERRAIN OF THE
WEST TEXAS AREA...THEN MOVE SLOWLY TO THE NORTHEAST DURING THE
EVENING HOURS...POSSIBLY MAKING THEIR WAY INTO OUR WESTERN TIER OF
COUNTIES BEFORE DISSIPATING.
THE UPPER LEVEL RIDGING EXPANDS THROUGH THE WEEKEND ACROSS TEXAS
AND THE REST OF THE SOUTHWESTERN U.S. THIS WILL PUSH THE MID/UPPER
LEVEL LOW BACK OUT TO THE PACIFIC...AND KEEP OUR TEMPERATURES
WARMER THAN NORMAL WITH LITTLE CHANCE FOR PRECIPITATION. BY
TUESDAY OF NEXT WEEK...A WEAK MID/UPPER LEVEL TROUGH DEVELOPS
ACROSS THE EASTERN HALF OF TEXAS...AND LOOKS TO DRIFT SLOWLY
WEST/SOUTHWEST ACROSS THE SOUTHERN HALF OF THE STATE. THIS COULD
RESULT IN SOME LOWERED TEMPERATURES...AND THE GFS/ECMWF ALSO TRY
TO SHOW SOME SHRA/TSRA DEVELOPING ACROSS OUR SOUTHEASTERN
COUNTIES. WILL HOLD OFF ON INTRODUCING ANY WX AT THIS TIME...BUT
IT WILL BE WORTH WATCHING.
20
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 72 93 72 94 71 / 20 10 10 10 10
SAN ANGELO 73 98 73 98 71 / 20 10 10 10 10
JUNCTION 74 98 73 94 72 / 20 10 10 10 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
352 PM CDT WED JUN 13 2012
.SHORT TERM...
BOUNDARY LAYER APPEARS TO BE FAIRLY STABLE OVER THE ROLLING PLAINS
THANKS TO OUTFLOW FROM THE STORMS THAT ROLLED ACROSS THIS AREA EARLY
THIS MORNING. ACROSS THE SOUTH PLAINS...LATEST VISIBLE SATELLITE
SHOWS THAT CU FIELD IS TRYING TO DEVELOP AND DEEPEN. RAP BUFKIT
SOUNDINGS CONTINUE TO INDICATE A WEAK CAP THAT IS BROKEN IN A COUPLE
OF HOURS AT KLBB WHILE HOLDING THE CAP IN PLACE FURTHER WEST AT
CLOVIS. SPC MESOSCALE ANALYSIS ALSO SHOWS THE CAP HOLDING OVER THE
ROLLING PLAINS WITH AN UNCAPPED ATMOSPHERE OVER THE SOUTH PLAINS AND
MLCAPE VALUES BETWEEN 3500-4000 J/KG. BULK SHEAR VALUES ARE A BIT
LOWER THAN YESTERDAY OVER THE ENTIRE AREA BUT 30-40 KNOTS IS IN
PLACE ACROSS THE SOUTHWESTERN QUARTER OF THE AREA. THESE FACTORS
COULD POTENTIALLY RESULT IN RAPID DEVELOPMENT OF SEVERE STORMS /IF/
THEY ARE ABLE TO DEVELOP. NOT SURE WHAT TO MAKE OF THE POSSIBLE CAP
OVER THE SOUTH PLAINS AND WHAT THIS MAY DO FOR OUR CHANCES OF
CONVECTION AND ALSO MAKES IT DIFFICULT TO NAIL DOWN THE POP FORECAST
FOR TONIGHT.
WILL HOLD POPS IN THE LOW END OF CHANCE AS THE TTU/OUN WRF AND THE
HRRR HAVE ALL BEEN CONSISTENT IN NOT GENERATING ANY STORMS OVER THE
AREA...WITH THE EXCEPTION OF THE HRRR TRYING TO DEVELOP SOME STORMS
LATE TONIGHT BETWEEN 03 AND 06Z. ALSO AM CONCERNED THAT THE
INCOMING AREA OF ENHANCED CLOUD COVER ON VISIBLE SATELLITE MAY
INDICATE SOME KIND OF POCKET OF COOLER AIR ALOFT AND SOME WEAK LIFT
THAT MAY HELP STORMS TO FIRE. THE FLAVORS OF THE WRF HAVE SHOWN
THAT ACTIVITY IN NORTHEAST NEW MEXICO MAY ORGANIZE INTO ANOTHER
COMPLEX THAT COULD MOVE TOWARDS THE NORTHERN ROLLING PLAINS
OVERNIGHT AND ONCE AGAIN HAVE KEPT SLIGHT CHANCE POPS ACROSS THIS
AREA THROUGH TOMORROW MORNING.
FOR THURSDAY...RIDGE AXIS TRIES TO PUSH OVERHEAD WHICH SHOULD HELP
SUPPRESS CONVECTION A BIT BUT OPTED TO HOLD SLIGHT CHANCE POPS
ACROSS THE WESTERN HALF DEPENDING ON HOW CONVECTION DEVELOPS
TONIGHT. MODELS STILL SHOW CONVECTION DEVELOPING ACROSS THE HIGHER
TERRAIN OF NM TOMORROW AFTERNOON SO CANNOT RULE OUT AN ISOLATED
STORM OR TWO PUSHING TOWARDS THE STATE LINE. TEMPERATURES MAY ALSO
BE A FEW DEGREES WARMER WITH THE RIDGE AXIS OVERHEAD BUT LOW-LEVEL
MOISTURE MAY HELP TO LIMIT THE WARMUP SOMEWHAT.
JORDAN
&&
.LONG TERM...
LATEST WATER VAPOR IMAGERY DISPLAYED A PACIFIC UL DISTURBANCE MOVING
ACROSS CALIFORNIA...AND IS PROGGED TO DIG ESE TOWARDS THE DESERT SW
TOMORROW NIGHT. THIS WILL PROMOTE SOUTHWESTERLY FLOW ALOFT...AND
THUS PERMIT THE DRYLINE TO NEAR THE TEXAS/NEW MEXICO BORDER.
FORECAST MODELS HINT AT ADEQUATE CONVERGENCE ALONG THE DRYLINE...SO
MUCH SO THAT IT WILL OVERCOME THE LESS THAN 100 J/KG OF CIN.
FURTHERMORE...A WEAK EMBEDDED IMPULSE MAY BE ENOUGH TO SPARK
CONVECTION ALONG AND EAST OF THE DRYLINE...AS SOUTHEASTERLY SFC
WINDS EAST OF THE DRYLINE INDUCE DEWPOINTS IN THE 50S AND 60S.
CURRENT THINKING IS THAT THE SAID EMBEDDED IMPULSE WILL EJECT NE
ACROSS THE PANHANDLES...HOWEVER WILL MAINTAIN SLIGHT CHANCE POPS
ACROSS PORTIONS OF THE CENTRAL AND WESTERN ZONES...WHERE PROGGED
SFC-BASED CAPE OF 1.0-1.5 KJ/KG EXISTS. IF STORMS DO INDEED
DEVELOP...STRONG TO SEVERE STORMS WILL BE POSSIBLE WITH HAIL AND
BRIEF GUSTY WINDS THE PRIMARY THREATS.
FRIDAY THROUGH SUNDAY...THE PACIFIC UL DISTURBANCE WILL RETROGRADE
WEST ACROSS THE EASTERN PACIFIC...WHILE CONCURRENTLY A PROGRESSIVE
PATTERN ACROSS THE NORTHERN U.S. TIER ENSUES...WHICH WILL LEAD TO
THE DRYLINE LINGERING ACROSS OR JUST WEST OF THE CWA. DESPITE SLIGHT
HEIGHT INCREASES FROM AN UA RIDGE...MOIST LOW LEVELS WILL EXIST AS
UPSLOPE SFC WINDS PERSIST /PWATS IN EXCESS OF 1.00 INCH/...AND MODEL
SOUNDINGS EXHIBITING STEEPENED LAPSE RATES EACH AFTERNOON/EVENING
/SFC-BASED CAPE OF 2.0-2.5 KJ/KG/ SUGGEST THE POTENTIAL FOR STRONG
TO SEVERE STORMS MORESO ACROSS THE WESTERN ZONES NEAREST TO THE
DRYLINE /HAIL AND GUSTY WINDS THE PRIMARY THREATS/. THE GFS
MAINTAINS BEST POPS ACROSS EASTERN NEW MEXICO COINCIDING WITH THE
DISPLACEMENT OF THE DRYLINE THROUGHOUT THE SAID PERIOD...WHILE THE
NAM AND ECMWF SOLUTIONS ARE A BIT MORE ROBUST /DRYLINE A BIT CLOSER
TO THE FA/. AS SUCH...STORMS APPEAR TO BE DEPENDENT ON THE EXACT
LOCATION OF THE DRYLINE AND WILL THEREFORE OPT TO KEEP POPS BELOW 30
PERCENT ATTM.
MONDAY THROUGH WEDNESDAY THE LONG TERM MODELS DIFFER A BIT IN REGARD
TO THE SYNOPTIC PATTERN. THE GFS RETROGRADES THE UA RIDGE TO THE
SOUTHWESTERN CONUS BY MONDAY AS AN EASTERN CONUS UA RIDGE PROMOTES
AN UA LOW TO MOVE ACROSS SOUTHERN TEXAS AND PERHAPS ALLOW INCREASING
CHANCES FOR PRECIP OFF THE CAPROCK TUESDAY-WEDNESDAY. THE ECMWF ON
THE OTHER HAND ALSO DEVELOPS AN UA RIDGE ACROSS THE EASTERN
CONUS...WHILE A TROPICAL SYSTEM TRANSLATES NORTH ACROSS OLD MEXICO
THUS STREAMING LOW TO MID LEVEL MOISTURE ACROSS THE FA...AND A
CHANCE FOR STORMS. FURTHERMORE...THE ECMWF HINTS AT THE BROAD UA
TROUGH ACROSS THE NORTHERN U.S. TIER TO SURGE A RELATIVELY WEAK DRY
COLD FRONT TO ACROSS FAR THE NWRN ZONES TUESDAY BEFORE QUICKLY
RETREATING NORTH. WILL NEED TO ANALYZE FUTURE MODEL RUNS FOR
CONSENSUS...AND WILL THEREFORE OPT TO MAINTAIN SILENT POPS BEYOND
SUNDAY NIGHT ATTM.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 61 93 64 92 62 / 40 20 20 30 30
TULIA 66 91 65 91 65 / 30 20 20 20 20
PLAINVIEW 69 92 67 91 67 / 30 20 20 20 20
LEVELLAND 69 95 67 93 66 / 30 20 20 20 20
LUBBOCK 69 94 69 93 68 / 30 20 20 20 20
DENVER CITY 69 95 68 94 66 / 30 20 20 30 30
BROWNFIELD 70 95 68 93 66 / 30 20 20 20 20
CHILDRESS 68 94 72 93 71 / 30 10 10 10 10
SPUR 70 94 70 93 69 / 30 10 20 20 20
ASPERMONT 73 95 74 95 71 / 20 10 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
14/29
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
348 PM CDT WED JUN 13 2012
.SHORT TERM...
WE HAD ISOLATED WEAK CONVECTION EARLY TODAY BUT THIS HAS SINCE
DISSIPATED. SKIES HAVE BECOME MOSTLY CLEAR TO PARTLY CLOUDY ACROSS
THE CWA LIKELY IN RESPONSE TO SUBSIDENCE IN THE WAKE OF THE
DEPARTING MCV ALONG THE RED RIVER VALLEY. A WEAK SURFACE...YET
DISCERNIBLE...BOUNDARY STILL EXISTS OVER THE SOUTHWEST CWA PER THE
KSJT WSR-88D BUT THIS FEATURE REMAINS BENIGN AT THIS TIME. LOOKING
WEST...MID LEVEL RADAR ECHOES HAVE BEEN INCREASING ACROSS
SOUTHWEST TX THIS AFTERNOON AHEAD OF AN APPROACHING SHORTWAVE. AS
THIS SYNOPTIC SCALE ASCENT OVERSPREADS THE AREA AND SURFACE TEMPS
WARM INTO THE MID/UPPER 90S...I ANTICIPATE CONVECTION DEVELOPING
IN THE VICINITY OF THE CWA. CONFIDENCE IS FAIRLY LOW THAT WE WILL
SEE WIDESPREAD THUNDERSTORMS BUT SEVERAL VERSIONS OF THE HIRES WRF
AND THE HRRR ALL AGREE IN THUNDERSTORMS FORMING OVER THE
CENTRAL/EASTERN COUNTIES.
A LOOK AT THE SPC MESO ANALYSIS PAGE DEPICTS SBCAPE VALUES ON THE
ORDER OF 2500-3500 J/KG WITH EFFECTIVE SHEAR VALUES BETWEEN 40-50
KTS. THE QUESTION WILL BE WHETHER OR NOT THE CAP WILL GIVE WAY.
THUS...WE DO HAVE A CONDITIONAL THREAT FOR SEVERE WEATHER BUT I AM
PLAYING THIS RATHER CONSERVATIVE FOR NOW THINKING THAT THE CAP
WILL HOLD FOR THE MOST PART AND ANY CONVECTIVE INITIATION WILL
LIKELY BE DELAYED UNTIL WELL AFTER PEAK HEATING. THUS...I AM ONLY
CARRYING 20 POPS FOR THE PERIOD BEGINNING AT 00Z. OVERNIGHT TEMPS
WILL FALL INTO THE LOWER 70S /BUT WILL LIKELY BE LOWER IF
CONVECTION DOES DEVELOP/.
GENERALLY DRY AND WARM CONDITIONS ARE EXPECTED FOR THURSDAY WITH
SOUTH WINDS INCREASING TO 10-20 MPH ACROSS THE CWA. HIGHS ARE
EXPECTED TO BE IN THE MID/UPPER 90S.
JOHNSON
.LONG TERM...
THURSDAY NIGHT INTO FRIDAY...THE UPPER LEVEL LOW THAT IS
CURRENTLY OVER SOUTHERN CALIFORNIA TODAY WILL BE ENVELOPED BY
ANOTHER LOW THAT WILL MOVE SOUTH ALONG THE CALIFORNIA COAST. THERE
WILL BE AN UPPER LEVEL TROUGH OVER THE GULF COAST REGION AS WELL
WHILE WEST CENTRAL TEXAS WILL BE IN BETWEEN UNDERNEATH RIDGING.
FOR THIS REASON...WILL GO WITH TEMPERATURES SLIGHTLY WARMER THAN
GUIDANCE FOR FRIDAY AND SATURDAY. HAVE NOT EXPANDED ANY OF THE
INHERITED POPS FRIDAY AFTERNOON AND EVENING. IT STILL APPEARS THAT
THE LOW WILL BE TOO FAR WEST TO DIRECTLY INFLUENCE US...AND THAT
MOST OF THE CONVECTION WILL GET GOING IN THE HIGHER TERRAIN OF THE
WEST TEXAS AREA...THEN MOVE SLOWLY TO THE NORTHEAST DURING THE
EVENING HOURS...POSSIBLY MAKING THEIR WAY INTO OUR WESTERN TIER OF
COUNTIES BEFORE DISSIPATING.
THE UPPER LEVEL RIDGING EXPANDS THROUGH THE WEEKEND ACROSS TEXAS
AND THE REST OF THE SOUTHWESTERN U.S. THIS WILL PUSH THE MID/UPPER
LEVEL LOW BACK OUT TO THE PACIFIC...AND KEEP OUR TEMPERATURES
WARMER THAN NORMAL WITH LITTLE CHANCE FOR PRECIPITATION. BY
TUESDAY OF NEXT WEEK...A WEAK MID/UPPER LEVEL TROUGH DEVELOPS
ACROSS THE EASTERN HALF OF TEXAS...AND LOOKS TO DRIFT SLOWLY
WEST/SOUTHWEST ACROSS THE SOUTHERN HALF OF THE STATE. THIS COULD
RESULT IN SOME LOWERED TEMPERATURES...AND THE GFS/ECMWF ALSO TRY
TO SHOW SOME SHRA/TSRA DEVELOPING ACROSS OUR SOUTHEASTERN
COUNTIES. WILL HOLD OFF ON INTRODUCING ANY WX AT THIS TIME...BUT
IT WILL BE WORTH WATCHING.
20
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 72 93 72 94 71 / 20 10 10 10 10
SAN ANGELO 73 98 73 98 71 / 20 10 10 10 10
JUNCTION 74 98 73 94 72 / 20 10 10 10 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
1249 PM CDT WED JUN 13 2012
.UPDATE...
18Z AVIATION DISCUSSION IS BELOW. DIFFICULT FORECAST FOR THIS
AFTERNOON AS NONE OF THE MESOSCALE MODELS ARE INDICATING
CONVECTION OVER THE FORECAST AREA...THE OPERATIONAL RUNS ARE...
AND THE LATEST RAP RUN WEAKENS THE CAP CONSIDERABLY WHICH ALL MEAN
CONDITIONS WILL NEED TO BE WATCHED. DEEP LAYER SHEAR PROFILE IS
MUCH WEAKER THAN YESTERDAY WITH SURFACE WINDS VEERING TO MORE OF A
SOUTHERLY DIRECTION THROUGH THE DAY AS OPPOSED TO SOUTHEASTERLY.
THERE IS A WEAK SURFACE TROF OVER THE AREA WHICH MAY PROVIDE AN
AREA OF SURFACE-BASED CONVERGENCE AND IF THE LATEST RAP RUNS ARE
CORRECT...SBCAPE VALUES OF BETWEEN 2000-3500 J/KG MAY BE REALIZED.
THESE TWO FEATURES MEAN THAT THERE IS STILL A POTENTIAL FOR SEVERE
CONVECTION THIS AFTERNOON...HOWEVER CONFIDENCE IS STILL PRETTY
LOW WHEN/IF ANYTHING CAN GO. WITH CAPE VALUES THIS HIGH...LARGE
HAIL WILL BE THE PRIMARY THREAT ALONG WITH SOME LOCALLY HEAVY
RAINFALL. WILL KEEP POPS THE WAY THEY ARE FOR NOW AND WILL
EVALUATE THROUGH THE DAY TO SEE IF THERE ARE ANY AREAS SHOWING A
TENDENCY FOR CONVECTIVE DEVELOPMENT AND ADJUST IF NEEDED.
JORDAN
&&
.AVIATION...
MVFR CONDITIONS AT KCDS SHOULD GRADUALLY GIVE WAY TO VFR THIS
AFTERNOON WITH VFR IN PLACE IN LUBBOCK. THERE DOES REMAIN A CHANCE
WE COULD SEE STORMS AT BOTH TERMINALS BUT THE TIMING OF THIS
POSSIBILITY IS HIGHLY UNCERTAIN AT THIS TIME AND WILL NOT INCLUDE
IN THE TAFS FOR NOW. MVFR CEILINGS COULD REDEVELOP AT BOTH
TERMINALS OVERNIGHT IF THERE ARE STORMS IN THE AREA AND WILL ALSO
MONITOR FOR POSSIBLE INCLUSION IN LATER TAF ISSUANCES.
JORDAN
&&
.PREV DISCUSSION... /ISSUED 640 AM CDT WED JUN 13 2012/
AVIATION...
OUTFLOW FROM OVERNIGHT CONVECTION WILL BRING MOIST EASTERLY WINDS
ACROSS THE AREA THIS MORNING WITH THE POTENTIAL FOR AREAS OF LOW
STRATUS. SAT IMAGERY AT 630 AM SHOWS EXPANDING STRATUS FIELD
ACROSS THE WESTERN SOUTH PLAINS. WITH LOW CONFIDENCE THAT MVFR
CEILINGS WILL IMPACT EITHER TERMINAL WE HAVE KEPT TAFS VFR FOR
NOW. THIS EVENING...WE EXPECT SCATTERED TSTM ACTIVITY ACROSS ERN
NM AND WRN SPLNS TO MOVE EAST TOWARD BOTH TERMINALS...WITH HIGHER
CONFIDENCE THAT STORMS WILL REACH THE CENTRAL SOUTH PLAINS WE HAVE
ADDED A PROB30 TO KLBB.
PREV DISCUSSION... /ISSUED 410 AM CDT WED JUN 13 2012/
DISCUSSION...
CONVECTIVE INITIATION AND LOCATION TODAY STILL REMAINS HIGHLY
UNCERTAIN ESPECIALLY WITH CONVECTION FROM EARLY THIS MORNING
STABILIZING THINGS OUT. WINDS SHOULD STILL BE ABLE TO SWING BACK
AROUND TO THE SOUTHEAST BY LATER THIS MORNING WITH STRONG SURFACE
DESTABILIZATION BY THE AFTERNOON. WITH THE OUTFLOW...A STRONG CAP
WILL BE IN PLACE AT LEAST THROUGH THE EARLY AFTERNOON. STEEP MID
LEVEL LAPSE RATES WILL CONTRIBUTE TO VERY STRONG SURFACE CAPE
VALUES BETWEEN 3000 AND 4000 J/KG ON THE CAPROCK. HOWEVER...LIFT
WILL BE SIGNIFICANTLY WEAKER THAN OBSERVED EARLY THIS MORNING. MID
AND UPPER LEVEL FLOW WILL BE WEAKER. UPPER LEVEL LIFT WILL
GENERALLY BE LESS ROBUST WITH A VERY WEAK JET MAX MOVING OVERHEAD.
THE ONLY LOW LEVEL CONVERGENCE WILL BE FOUND NEAR THE MOUNTAINS IN
EASTERN NEW MEXICO. WEAK HEIGHT FALLS WILL NOT MOVE INTO THE AREA
UNTIL EARLY THIS EVENING. CONVECTION DOES APPEAR POSSIBLE BUT
LOCATION IS EXTREMELY DIFFICULT TO DETERMINE AT THE MOMENT. THE
BEST CHANCES WILL LIKELY EXIST ON THE CAPROCK THIS EVENING.
BEGINNING ON THURSDAY...A TROUGH WILL AMPLIFY ACROSS THE DESERT
SOUTHWEST. THIS WILL CAUSE THE UPPER FLOW OVER WEST TEXAS TO TURN
SOUTHWESTERLY. HOWEVER...THIS FLOW WILL ALSO SUBSTANTIALLY WEAKEN.
HEIGHT RISES ON THURSDAY WILL ALSO NOT BODE WELL FOR CONVECTION.
LOW LEVEL SOUTHEASTERLY FLOW WILL CONTINUE TO KEEP MOISTURE IN THE
AREA. NONETHELESS...HAVE STILL INCLUDED SLIGHT CHANCES FOR THUNDER
ACROSS WESTERN AREAS ON THURSDAY. PRECIPITATION CHANCES MAY BE
BETTER ON FRIDAY WHEN THE MID AND UPPER FLOW WILL INCREASE A BIT.
DIFFLUENCE WILL ALSO BE SEEN ALOFT ALTHOUGH THE JET MAX WILL STILL
BE WELL TO THE SOUTHWEST OF THE REGION. DETAILS ARE STILL SKETCHY
FOR THE WEEKEND WITH CONVECTION POSSIBLE EACH DAY THROUGH SUNDAY.
SOUTHEASTERLY FLOW WILL HELP TO KEEP LOW LEVEL MOISTURE IN THE
AREA WITH AN UNSTABLE ATMOSPHERE DURING THE AFTERNOON HOURS.
PRECIPITABLE WATER VALUES WILL ALSO INCREASE THROUGH THE WEEKEND
BEGINNING ON FRIDAY. MODELS ALSO SHOW MID LEVEL TEMPERATURES
COOLING ON SATURDAY AND SUNDAY INDICATING INCREASED INSTABILITY
AND LESS CHANCE OF A CAP THESE DAYS. THINGS LOOK TO THEN DRY OUT A
BIT EARLY NEXT WEEK WITH A POSSIBLE FRONTAL PASSAGE ON TUESDAY.
JDV
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 89 64 92 63 91 / 30 30 20 20 30
TULIA 86 64 91 64 91 / 30 30 20 20 20
PLAINVIEW 85 65 91 66 91 / 30 30 20 20 20
LEVELLAND 91 67 94 66 92 / 30 30 20 20 20
LUBBOCK 89 69 93 68 92 / 30 30 20 20 20
DENVER CITY 94 70 94 69 92 / 30 30 20 20 30
BROWNFIELD 93 70 94 69 92 / 30 30 20 20 20
CHILDRESS 88 70 92 72 93 / 30 30 10 10 10
SPUR 90 69 93 69 93 / 30 30 20 20 10
ASPERMONT 93 72 95 73 95 / 20 20 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/99/99
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
402 PM CDT WED JUN 13 2012
.SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT
356 PM CDT WED JUN 13 2012
AT 3 PM...A CONVECTIVELY INDUCED VORTICITY MAXIMUM WAS MOVING
THROUGH NORTH-CENTRAL IOWA AND SOUTH-CENTRAL MINNESOTA. THE LAPS
INDICATES MODERATE TO STRONG 800-600 MB FRONTOGENESIS ACROSS
SOUTHEAST MINNESOTA AND NORTHEAST IOWA. THE LATEST RAP CONTINUES
TO SHOW THAT THIS FRONTOGENESIS WILL CONTINUE TO WEAKEN LATE THIS
AFTERNOON. AS THIS OCCURS...EXPECT THE BAND OF SHOWERS JUST TO OUR
WEST WILL CONTINUE TO WEAKEN AND DISSIPATE. THIS IS IN GOOD
AGREEMENT WITH THE HRRR...EAST ARW...AND EAST NMM.
FOR TONIGHT...THE 13.12Z MODELS ARE IN GOOD AGREEMENT THAT STRONG
925 TO 700 MB MOISTURE TRANSPORT WILL DEVELOP ACROSS NORTHERN AND
WESTERN MINNESOTA. THIS IS IN RESPONSE TO A WARM FRONT MOVING
THROUGH THIS REGION. ALL OF THE MESO MODELS AND BROADER SCALE
MODELS ARE IN FAIRLY GOOD AGREEMENT THAT A MAJORITY OF THE
PRECIPITATION OVERNIGHT WILL BE WEST OF A CHARLES CITY IOWA TO
DIAMOND LAKE WISCONSIN LINE.
ON THURSDAY AFTERNOON AND EVENING...THE MODELS ARE SHOWING THAT
THERE WILL INCREASING SHEAR ACROSS EASTERN MINNESOTA...AND
NORTHERN WESTERN WISCONSIN AS A STRONG WAVE SHORT WAVE MOVES
ACROSS NORTHERN MINNESOTA. BULK SHEARS CLIMB ABOVE 40 KNOTS ACROSS
THE AFOREMENTIONED AREAS WHICH WILL MAKE IT FAVORABLE FOR THE
DEVELOPMENT OF SUPERCELL THUNDERSTORMS. THE SIGNIFICANT TORNADO
PARAMETER SUGGESTS THAT THERE WILL BE THE POTENTIAL OF TORNADOES.
THE NAM/WRF WOULD SUGGEST EAST-CENTRAL MINNESOTA AND NORTHWEST
WISCONSIN. MEANWHILE THE GFS INDICATES THAT THIS MAY BE A BIT
FURTHER SOUTH AND IT WOULD INCLUDE SOUTHEAST MINNESOTA AND WEST-
CENTRAL WISCONSIN. WHILE THE SHEAR IS GOOD...THERE IS SOME
CONCERN THAT THAT DEW POINTS IN THE MODELS MAY BE A BIT TOO
HIGH...AND IF THIS IS TRUE THAN THE CAPES MAY BE TOO HIGH TOO.
THE TORNADO THREAT WOULD LIKELY IN THE MID TO LATE AFTERNOON...AND
THEN EVOLVE INTO A WIND THREAT AS THE COLD POOLS COALESCE.
BEYOND THIS TIME PERIOD...THERE IS A LOT OF UNCERTAINTY ON WHERE
THE FRONT WILL BE LOCATED ACROSS THE REGION. DUE TO THIS...THERE
IS LOW CONFIDENCE ON BOTH THE TEMPERATURE AND PRECIPITATION
FORECAST.
.LONG TERM...SATURDAY THROUGH WEDNESDAY
356 PM CDT WED JUN 13 2012
ON SATURDAY AND SATURDAY NIGHT...THE MODELS SUGGEST THAT A COLD
FRONT AND UPPER LEVEL TROUGH WILL BE MOVING THROUGH THE REGION.
THE BULK SHEAR WILL ONCE AGAIN CLIMB ABOVE 40 KNOTS. THIS WOULD BE
CONDUCIVE FOR THE DEVELOPMENT OF SUPERCELL THUNDERSTORMS. HOWEVER
THERE IS QUITE A BIT OF UNCERTAINTY ON WHEN THE COLD FRONT WILL
MOVE THROUGH THE REGION AND HOW MUCH INSTABILITY WILL BE AHEAD OF
IT.
ON SUNDAY AND SUNDAY NIGHT...BOTH THE GEM AND ECMWF INDICATE THAT
THE AREA MAY BE DRY AS HIGH PRESSURE BUILDS ACROSS THE REGION.
MEANWHILE THE GFS IS SHOWING YET ANOTHER FRONT MOVING INTO THE
REGION. DUE TO THIS THE ALL BLEND POPS WERE REDUCED SOME.
LOOKING TOWARD THE MIDDLE OF NEXT WEEK...THERE LOOKS TO BE A
PATTERN CHANGE BACK TO NORTHWEST FLOW AS A TROUGH BUILDS ACROSS
THE REGION. THE GFS IS NOT AS AGGRESSIVE AS THE ECMWF. HOWEVER
LOOKING WITH A MADDEN JULIAN OSCILLATION MOVING FROM PHASE 6 TO
7...THE ECMWF WOULD BE THE MOST PROBABLE OUTCOME.
&&
.AVIATION...THROUGH 18Z THURSDAY
101 PM CDT WED JUN 13 2012
VFR CONDITIONS EXPECTED THROUGH THE PERIOD WITH MAIN FORECAST
CONCERNS ON PRECIPITATION CHANCES OVERNIGHT AND THURSDAY. FOR THIS
AFTERNOON...WEAK SHORTWAVE MOVING ACROSS AREA RESULTING IN
ISOLATED SPRINKLES ACROSS SOUTHERN MINNESOTA AND NORTHERN IOWA.
DRY AIR IN THE LOW LEVELS IS KEEPING CLOUD BASES AT OR ABOVE 8
KFT. FOR THE OVERNIGHT...BROKEN TO SCATTERED MID TO HIGH LEVEL
DECK WILL PERSIST AND AS 850 MB MOISTURE TRANSPORT INCREASES TO
THE WEST...SHOWERS AND THUNDERSTORMS LOOK TO DEVELOP ACROSS
CENTRAL MINNESOTA. CURRENT THINKING IS THIS ACTIVITY WILL REMAIN
NORTH AND WEST OF KRST/KLSE SO FOR NOW HAVE LEFT OUT OF TAFS...BUT
WILL NEED TO MONITOR CLOSELY. AN INCREASINGLY TIGHTER PRESSURE
GRADIENT THURSDAY MORNING / AFTERNOON WILL LEAD TO BREEZY
SOUTHERLY WINDS WITH GUSTS TO AROUND 25 KTS AT KRST AND 20 KTS AT
KLSE. LOOKING AHEAD...A COLD FRONT WILL APPROACH THE AREA THURSDAY
EVENING...BRINGING THE CHANCE OF SHOWERS AND THUNDERSTORMS TO THE
AREA.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
356 PM CDT WED JUN 13 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...ZT
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
101 PM CDT WED JUN 13 2012
.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
325 AM CDT WED JUN 13 2012
MAIN FORECAST CONCERN DEALS WITH RAIN CHANCES TODAY THROUGH FRIDAY
NIGHT.
WATER VAPOR IMAGERY AND RAP ANALYSIS AT 2 AM SHOWS A DISTINCT
MID-LEVEL CYCLONIC CIRCULATION MOVING EAST ACROSS CENTRAL SD.
MOISTURE TRANSPORT AND ISENTROPIC LIFT AHEAD OF THE WAVE AIDING IN
SHOWERS AND ISOLATED THUNDERSTORMS ACROSS EASTERN SD/NEB...INTO
NORTHWEST IA. CLOSER TO HOME OVER OUR FORECAST AREA...HIGH CLOUDS
FROM THE DAKOTAS WAVE STREAMING IN WITH CENTER OF HIGH PRESSURE
ACROSS CENTRAL WI INTO CENTRAL LOWER MI. LIGHT WINDS AND PARTLY
CLOUDY CONDITIONS HAS ALLOWED TEMPERATURES TO DIP TO 37 DEGREES AT
BLACK RIVER FALLS WI...WHILE OTHER LOCATIONS RANGED FROM THE 40S TO
THE LOWER 50S UNDER MORE CLOUD COVER.
13.00Z NCEP MODEL SUITE/ECMWF/GEM GENERALLY IN GOOD AGREEMENT
THROUGH THE SHORT TERM PERIOD.
FOR TODAY...WILL BE WATCHING THAT MID-LEVEL WAVE OVER SD MOVES INTO
CENTRAL MN THROUGH THIS AFTERNOON. MODELS CONCENTRATE MAIN AXIS OF
ASSOCIATED 850MB MOISTURE TRANSPORT NORTHWEST INTO MN WITH OUR AREA
JUST ON THE EASTERN FRINGES. MEANWHILE...DECENT AMOUNT OF ISENTROPIC
LIFT INTO THE AREA FOR MID-CLOUD/ACCAS GENERATION. KEPT SMALL
CHANCES OF SHOWERS MAINLY NORTHWEST OF A LINE FROM MEDFORD AND
ARCADIA WI...TO ROCHESTER AND AUSTIN MN. OTHERWISE...WITH INCREASING
CLOUD COVER EXPECTED...HIGHS TODAY ARE EXPECTED TO TOP OFF IN THE
LOWER TO MIDDLE 70S.
TONIGHT...ANOTHER MID-LEVEL WAVE AND SURFACE CYCLOGENESIS WILL TAKE
PLACE OVER NEB/SD WITH MOISTURE TRANSPORT/ISENTROPIC LIFT IMPINGING
ON THE WESTERN PORTIONS OF THE FORECAST AREA. PLANNING ON ISOLATED
SHOWER AND ISOLATED THUNDER //WITH INCREASING ELEVATED MUCAPE//
NORTHWEST OF A MEDFORD-ARCADIA-ROCHESTER-AUSTIN LINE AGAIN IN THE
EVENING...THEN INCREASING SLIGHTLY IN COVERAGE/SPREADING EAST INTO
THE REST OF THE AREA AFTER MIDNIGHT AS 850MB MOISTURE TRANSPORT
VECTORS BEND MORE INTO THE AREA. RAINFALL LOOKS VERY LIGHT WITH
GENERALLY LESS THAN 5 HUNDREDTHS OF AN INCH EXPECTED.
ON THURSDAY...LOOK FOR THE MID-LEVEL WAVE/SURFACE COLD FRONT TO MOVE
INTO MN WITH INCREASING 850MB MOISTURE TRANSPORT INTO THE AREA.
0-3KM MLCAPE INCREASES INTO THE 1000-1500J/KG RANGE ALONG AND AHEAD
OF THE FRONT JUST TO OUR WEST WITH RESPECTABLE 20-30KT 0-3KM BULK
SHEAR. THEREFORE...EXPECTING STRONGER THUNDERSTORM ACTIVITY ALONG
THE FRONT BY AFTERNOON WITH EASTERN FRINGES OF THIS ACTIVITY PERHAPS
MAKING IT INTO NORTHWEST PORTIONS OF THE FORECAST AREA. FOR
NOW...WILL STICK WITH 20-40 PERCENT SHOWER/THUNDERSTORM CHANCE
NORTHWEST OF A SPARTA-VIROQUA-OELWEIN LINE. OTHERWISE...LOOK FOR
HIGH TEMPERATURES IN THE UPPER 70S TO LOWER 80S.
FOR THURSDAY NIGHT THROUGH FRIDAY NIGHT...LOOK FOR THE COLD FRONT
OVER MN TO SINK INTO THE AREA WHILE WEAKENING. MEANWHILE...MODELS
SHOWING A COUPLE MID-LEVELS WAVE EJECTING NORTHEAST TOWARD/ACROSS
THE AREA WITH BOUTS OF LIFT/MOISTURE TRANSPORT. BASED ON THIS
SIGNAL...WILL GO WITH 30-50 SHOWER/THUNDERSTORM CHANCES FOR NOW FOR
THIS PERIOD.
.LONG TERM...SATURDAY THROUGH TUESDAY
325 AM CDT WED JUN 13 2012
13.00Z GFS/ECMWF SHOWING SOUTHWEST FLOW ALOFT INTO THE AREA THROUGH
THE PERIOD AS HIGH PRESSURE ANCHORS IN ACROSS THE EASTERN CONUS AND
A TROUGH SLOWLY MAKES ITS WAY ACROSS THE INTERMOUNTAIN WEST INTO THE
PLAINS. SIGNAL AGREEMENT BETWEEN THE MODELS SEEMS TO BE GETTING
STRONGER FOR PERIODIC SHOWER/THUNDERSTORM CHANCES THROUGH THE
WEEKEND. BOTH MODELS THEN BRING IN A DEEPER TROUGH/STRONGER SURFACE
COLD FRONT INTO THE AREA MONDAY THROUGH TUESDAY FOR CONTINUED
SHOWER/THUNDERSTORM CHANCES.
&&
.AVIATION...THROUGH 18Z THURSDAY
101 PM CDT WED JUN 13 2012
VFR CONDITIONS EXPECTED THROUGH THE PERIOD WITH MAIN FORECAST
CONCERNS ON PRECIPITATION CHANCES OVERNIGHT AND THURSDAY. FOR THIS
AFTERNOON...WEAK SHORTWAVE MOVING ACROSS AREA RESULTING IN
ISOLATED SPRINKLES ACROSS SOUTHERN MINNESOTA AND NORTHERN IOWA.
DRY AIR IN THE LOW LEVELS IS KEEPING CLOUD BASES AT OR ABOVE 8
KFT. FOR THE OVERNIGHT...BROKEN TO SCATTERED MID TO HIGH LEVEL
DECK WILL PERSIST AND AS 850 MB MOISTURE TRANSPORT INCREASES TO
THE WEST...SHOWERS AND THUNDERSTORMS LOOK TO DEVELOP ACROSS
CENTRAL MINNESOTA. CURRENT THINKING IS THIS ACTIVITY WILL REMAIN
NORTH AND WEST OF KRST/KLSE SO FOR NOW HAVE LEFT OUT OF TAFS...BUT
WILL NEED TO MONITOR CLOSELY. AN INCREASINGLY TIGHTER PRESSURE
GRADIENT THURSDAY MORNING / AFTERNOON WILL LEAD TO BREEZY
SOUTHERLY WINDS WITH GUSTS TO AROUND 25 KTS AT KRST AND 20 KTS AT
KLSE. LOOKING AHEAD...A COLD FRONT WILL APPROACH THE AREA THURSDAY
EVENING...BRINGING THE CHANCE OF SHOWERS AND THUNDERSTORMS TO THE
AREA.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
325 AM CDT WED JUN 13 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...ZT