Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 05/16/12
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1112 PM MDT SUN MAY 13 2012
.AVIATION...
WEAK OUTFLOW BOUNDARY HEADING WESTWARD TOWARDS KCOS AND KPUB WILL
SHIFT WINDS FROM A LIGHT EASTERLY DIRECTION AT THE START OF THE
TAF ISSUANCE. WIND SPEEDS WILL REMAIN LESS THAN 10 KTS.
OTHERWISE...WITH CLEARING SKIES ALOFT...MOIST LOW LEVELS AND A
WEAK EASTERLY WIND...THERE IS STILL THE POTENTIAL FOR SOME
FRAGMENTED STRATUS DEVELOPMENT WITH BASES AROUND 010. WILL KEEP
THE SCT010 LAYER IN GOING TAFS AFTER 09Z...WITH POTENTIAL FOR
GROUND FOG AS NORTHERLY DRAINAGE WIND PICKS UP AT KCOS WHICH
SHOULD HELP PREVENT ANY WIDESPREAD PERSIST STRATUS DEVELOPMENT.
PERHAPS A LITTLE BETTER CHANCE FOR STRATUS AT KPUB THROUGH THE
MORNING HOURS. MON MORNING...CLEARING SKIES AND LIGHT WINDS WILL
KEEP CONDITIONS IN THE VFR CATEGORY FOR ALL 3 TAF SITES WITH WIND
SPEEDS UNDER 10 KTS. -KT
&&
.PREV DISCUSSION... /ISSUED 956 PM MDT SUN MAY 13 2012/
UPDATE...
UPDATED FORECAST TO DECREASE POPS ACROSS WESTERN AND NORTHERN
PORTIONS OF THE FORECAST AREA. SCATTERED TO WIDESPREAD SHOWERS
WITH EMBEDDED THUNDERSTORMS WILL CONTINUE ACROSS THE SOUTHEAST
PLAINS THROUGH 06Z BEFORE DIMINISHING ACROSS MOST OF THE AREA BY
09Z. HRRR SEEMS TO HAVE A FAIR HANDLE ON THE PROGRESSION OF THE
PCPN...AND HAVE FOLLOWED IT FOR POPS IN THE LATEST GRID UPDATE. -KT
AVIATION...
OUTFLOW BOUNDARIES FROM CONVECTION OUT EAST ARE HEADING WESTWARD
TOWARDS KCOS AND KPUB...AND MAY BRING A BRIEF WIND SHIFT FROM AN
EASTERLY DIRECTION TO BOTH TERMINALS BETWEEN 04 AND 06Z. THIS MAY
HELP WITH SOME LOW STRATUS DEVELOPMENT AND WILL CONTINUE TO BE
MONITORED TOWARDS THE 06Z TAF ISSUANCE. -KT
PREV DISCUSSION... /ISSUED 242 PM MDT SUN MAY 13 2012/
SHORT TERM...
(TONIGHT AND MONDAY)
.ONE LAST CHANCE AT GETTING SOME RAIN...
UPPER LOW CENTER IS DROPPING SOUTH ACROSS WESTERN COLORADO CENTERED
NEAR GRAND JUNCTION AT THE PRESENT TIME. LEFT FRONT QUADRANT
ACTIVITY ASSOCIATED WITH 70 KNOT JETSTREAM MAXIMA MOVING BY TO THE
SOUTH OF THE 4 CORNERS...IS TRIGGERING WIDESPREAD SHOWERS AND
THUNDERSTORMS OVER THE SOUTHERN HALF OF THE FORECAST AREA. NORTHERN
HALF OF THE FORECAST AREA IS BEING AFFECTED BY LIFT ASSOCIATED WITH
UPPER LEVEL DIFFLUENT FLOW AND COLD POOL NEAR UPPER LOW CENTER.
THE 2 FEATURES WILL COMBINE TO GIVE MUCH OF SOUTHERN COLORADO
ANOTHER SHOT AT SHOWERS AND THUNDERSTORMS THROUGH THIS EVENING...
BEFORE EVERYTHING SHIFTS SOUTH INTO NEW MEXICO AFTER MIDNIGHT. SO
FAR TODAY...THERE HAVE BEEN PEA TO HALF INCH SIZE HAIL REPORTS IN AN
AND AROUND THE AREA. A BRIEFLY INTENSE PULSE STORM THAT DEVELOPED
NEAR FLORISSANT EARLIER...HAD A 48 DBZ CORE UP TO ABOUT 34,000 FEET
MSL...MINOR ROTATION...AND A VIL HITTING 30. AT THAT ELEVATION...IN
THIS ENVIRONMENT...WITH A GOOD AMOUNT OF COLD AIR ALOFT...SOME
QUARTER SIZE HAIL WAS CERTAINLY PLAUSIBLE. SAW THIS HAPPEN FROM A
STORM 2 MILES EAST OF SOUTH FORK YESTERDAY. FOR THE REMAINDER OF
THE EVENING...EXPECT SHOWERS AND THUNDERSTORMS TO SPREAD OFF OF THE
MOUNTAINS ONTO THE PLAINS AND CONTINUE EASTWARD...PROBABLY WITH
BETTER SUCCESS THAN LAST NIGHT. ATMOSPHERE IS A BIT LESS STABLE
TODAY AND DEWPOINTS ARE NOW WIDESPREAD LOWER TO UPPER 40S ACROSS THE
PLAINS. THIS SHOULD HELP THE SUCCESS OF THE EVENING CONVECTION
ACROSS THE PLAINS.
MOST ACTIVITY SHOULD SHIFT SOUTH INTO NEW MEXICO BY MIDNIGHT...WITH
JUST SOME LINGERING ACTIVITY SOUTHERN AREAS PAST MIDNIGHT. COULD
SEE SOME PATCHY GROUND FOG IN A LOT OF AREAS TOWARD MORNING AS SKIES
START TO CLEAR. ONCE THE FOG GETS OUT OF HERE IN THE MORNING...WE
SHOULD BE LOOKING AT A MOSTLY SUNNY DAY WITH VERY PLEASANT SEASONAL
SPRING TEMPERATURES. STILL AN ISOLATED STORM CHANCE SOUTHERN
MOUNTAIN AREAS...BUT LIKELY THE EXCEPTION...NOT THE RULE.
THIS JUST IN...JUST HEARD FROM ONE OF OUR HAM RADIO COOPERATORS.
APPARENTLY...THE CELL THAT WAS WARNED ON OVER TELLER COUNTY EARLIER
DROPPED PEA SIZE HAIL...TO A 1 INCH DEPTH...IN A SWATH FROM THE LAKE
GEORGE AREA EASTWARD THROUGH THE FLORISSANT CANYON...TO WITHIN 5
MILES OR SO WEST OF WOODLAND PARK. ALSO GOT A REPORT FROM ANOTHER
SPOTTER 2 MILES NORTH OF WOODLAND PARK OF 1/2 DIAMETER HAIL IN THE
PAST HOUR. SPRINGTIME IS FUN TIME IN THE ROCKIES. LW
LONG TERM...
(MONDAY NIGHT THROUGH NEXT SUNDAY)
REST OF THE WEEK INTO NEXT WEEKEND LOOKS RELATIVELY BENIGN WITH
GENERALLY ABOVE AVERAGE TEMPERATURES AND NO SIGNIFICANT STORMS ON
THE HORIZON.
TUESDAY...SHOULD BE WARM AND DRY AS AN UPPER RIDGE MOVES SEWD
THROUGH CO. TEMPS SHOULD CLIMB INTO THE 80S OVR THE PLAINS...AND
50S-60S FOR THE MTN AREAS. BY WED...FIRST OF A COUPLE SHORT WAVES
MOVES THROUGH FROM THE W. THE TROUGH AXIS LOOKS TO BE MOSTLY EA OF
OUR AREA BY 00Z THU...AND BEST MID LEVEL WINDS AND FORCING LOOK TO
BE FARTHER N...SO STRONGEST AFTERNOON OR EVE CONVECTION AT THIS
POINT LOOKS TO BE MAINLY NE OF OUR CWA. HAVE INTRODUCED LOW POPS
HOWEVER FOR THE ERN PLAINS IN THE LATE AFTERNOON AND EVENING HOURS.
THERE IS JUST ENOUGH BULK SHEAR AND INSTABILITY THAT A COUPLE STRONG
STORMS CANNOT BE RULED OUT.
THE RIDGE REBUILDS THU INTO FRI...AND AGAIN IT SHOULD BE MOSTLY DRY
BOTH DAYS FOR THE ENTIRE AREA...WITH TEMPS IN THE UPPR 80S TO
POSSIBLY NR 90 DEGREES OVR THE PLAINS. NEXT DISTURBANCE MOVES IN
LATE FRI INTO SAT...AND A COLD FRONT ASSOCIATED WITH THIS SYSTEM
WILL PUSH INTO ERN CO SOMETIME ON SAT. SOME POTENTIAL FOR STRONGER
CONVECTION WITH THIS SYSTEM...AS DEEPER MOISTURE WITH HIGHER
DEWPOINTS BEGINS TO SURGE WWD OVR THE PLAINS BY LATE IN THE DAY OR
INTO SUN. NOT VERY CONFIDENT WITH THE MODEL SOLUTIONS FOR THE LATTER
PART OF THE WEEKEND...AS THE GFS AND ECMWF CONTINUE TO BE OUT OF
PHASE BEYOND SAT. 44
AVIATION...
CATTERED THUNDERSTORMS HAVE DEVELOPED OVER THE HIGHER TERRAIN AND
WILL SPREAD ONTO THE PLAINS THROUGH THE REMAINDER OF THE AFTERNOON
INTO THE EVENING. WILL CONTINUE AT LEAST VCTS MENTION ALL TAF SITES
THROUGH 02Z TIME PERIOD...WITH POTENTIAL FOR AT LEAST BRIEF MVFR
CONDITIONS UNDER A FEW OF THE STRONGER STORMS. MAINLY VFR CONDITIONS
SPREADING FROM NORTH TO SOUTH 03Z-06Z TIME FRAME AS TSRA MOVE INTO
NM...THOUGH DUE TO RECENT PRECIPITATION AND LIGHT WINDS...WILL HAVE
TO WATCH FOR PATCHY GROUND FOG DEVELOPMENT AROUND SUNRISE MONDAY...
ESPECIALLY AT KALS AND KPUB. LW
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
31/13
AREA FORECAST DISCUSSION
NWS ALBANY NY
649 AM EDT MON MAY 14 2012
.SYNOPSIS...
A STATIONARY FRONT WILL SERVE AS PATHWAY FOR SEVERAL DISTURBANCES TO
MOVE ALONG IT...STARTING TODAY...THROUGH TUESDAY NIGHT. TODAY
DISTURBANCES LOOK FAIRLY WEAK BRAINING SCATTERED TO NUMEROUS
SHOWERS. HOWEVER...A STRONGER DISTURBANCE TONIGHT WILL LIKELY BRING
A SOAKING POTENTIALLY HEAVY RAINFALL...TO MAINLY CENTRAL AND
SOUTHERN PORTIONS OF OUR REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 630 AM...BASED ON REGIONAL RADARS AND THE HRRR EXPERIMENTAL
MODEL...HAVE DECIDED TO GO BACK TO THE IDEA OF A MORE STEADIER RAIN
(ALBEIT LIGHT) THIS MORNING THEN A BREAK IN THE RAIN (SCATTERED
SHOWERS)DURING MUCH OF THE AFTERNOON. ACTUALLY...THE 00Z NAM
SUPPORTED THIS IDEA. THE 06Z GFS STILL BRINGS HEAVIER RAIN IN THIS
AFTERNOON...BUT AGAIN REGIONAL RADAR DOES NOT SUPPORT THIS IDEA.
TINKERED WITH THE QPF BUT NOT MUCH TO REFLECT THIS MODIFICATION IN
THINKING.
EITHER WAY...IT WILL REMAIN DAMP AND PROBABLY WILL SEE SCATTERED
SHOWERS OR PATCHY DRIZZLE THIS AFTERNOON ALONG WITH LOTS OF CLOUDS.
NO OTHER CHANGES OTHER THEN TO RE-TOOL THE HOURLY GRIDS...WHICH WERE
IN PRETTY GOOD SHAPE.
RAINFALL AMOUNTS LOOK TO BE A QUARTER TO MAYBE HALF AN
INCH...LIGHTER AMOUNTS UNDER QUARTER OF AN INCH TO THE NORTHWEST.
THE CLOUDS AND SHOWERS SHOULD KEEP TEMPERATURES DOWN
TODAY...GENERALLY HELD TO THE 60S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
CONFIDENCE IS NOW HIGHER THAT THE AXIS OF HEAVY RAIN TONIGHT THROUGH
TUESDAY NIGHT WILL GENERALLY RUN FROM THE CATSKILLS...NORTHEAST
ACROSS THE GREATER CAPITAL DISTRICT INTO THE SOUTHERN VERMONT.
THE SYNOPTIC SETUP DOES NOT REALLY LOOK LIKE A CLASSICAL HEAVY
RAINFALL EVENT...BUT CERTAINLY A MODERATE ONE. THE UPPER AIR TROUGH
IS SOMEWHAT WEAK. THERE WILL BE A LOW LEVEL JET...POSSIBLY
INCREASING TO 40KTS TRANSPORTING PWAT VALUES APPROACHING AN INCH AND
HALF FROM ALBANY SOUTHWARD. THE FLOW LOOKS TO BE SSE TO
SOUTHERLY...THROUGHOUT THE COLUMN.
A STRONGER DISTURBANCE...STILL DEVELOPING DOWN IN THE TENNESSEE
VALLEY...WILL BE THE ONE TO BRING MORE SIGNIFICANT RAINFALL TONIGHT
THROUGH TUESDAY NIGHT AS OUR CENTRAL AND EVENTUALLY SOUTHEAST AREAS
COME UNDERNEATH MID LEVEL FRONTOGENESIS AND ASSISTANCE FROM
DIVERGENCE ALOFT UNDERNEATH THE LEFT ENTRANCE OF AN UPPER LEVEL JET.
THE TOTAL QPF AMOUNT IS STILL SOMEWHAT UNCERTAIN AS THERE IS SOME
DISPARITY WITH THE CANADIAN AND EUROPEAN MODELS GENERALLY GIVING A
TOTAL RAINFALL IN THE 1-2 INCH RANGE...WHILE THE GFS AND NAM WERE
MORE IN THE 2-3+ INCH RANGE.
FOR NOW...PER HPC...HAVE LEANED WITH THE AMERICAN MODELS. MORE ABOUT
THE QPF AND WHAT IT COULD FOR OUR HYDROLOGICAL SERVICE AREAS (HSA)
CAN BE FOUND IN OUR HYDROLOGY SECTION.
SHOWALTER INDICES REMAINED POSITIVE WITH VERY LITTLE IF ANY SURFACE
INSTABILITY THROUGH TONIGHT. ON TUESDAY SHOWALTER VALUES LOOK TO
APPROACH ZERO SO WE WILL INCLUDE A SLIGHT CHANCE OF THUNDER.
THE UPPER LEVEL TROUGH LOOKS TO BEGIN TO SLOWLY SHIFT EASTWARD
TUESDAY TAKING THE SURFACE FRONT WITH IT AS IT GETS A KICK FROM
ANOTHER UPSTREAM DISTURBANCE. THE MODERATE TO HEAVY RAIN WILL SHIFT
EASTWARD AS WELL...AND FINALLY END.
HOWEVER...THE "KICKER"...ANOTHER COLD FRONT...COULD PRODUCE A ROUND
OF SHOWERS AND EVEN THUNDERSTORMS OF ITS OWN WEDNESDAY. THIS LOOKS
TO BE A MUCH FASTER MOVING SYSTEM SO ANY PRECIPITATION WITH IT
SHOULD NOT BE NEARLY AS HEAVY OR PROLONGED.
WITH CLOUDS AND RAIN...THERE WILL BE VERY LITTLE RANGE IN DIURNAL
TEMPERATURES THROUGH TUESDAY NIGHT. OVERNIGHT LOWS WILL BE IN THE
50S TO AROUND 60 AND DAYTIME HIGHS IN THE 60S.
BY WEDNESDAY...WE EXPECT BREAKS OF SUNSHINE MIDDAY AND AFTERNOON
ALONG WITH CONTINUE H850 TEMPERATURES NOT FAR FROM +10C.
THEREFORE...LOOK FOR A BOUNCE IN TEMPERATURES AS THEY RISE BACK
THROUGH THE 70S...POSSIBLY TOUCHING 80 IN SOME OF THE WARMEST SPOTS
MAINLY SOUTH OF ALBANY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A LARGE HIGH PRESSURE SYSTEM WILL BEGIN BUILDING EAST FROM THE GREAT
LAKES REGION WEDNESDAY NIGHT...AND BE OVER THE REGION THURSDAY NIGHT
AND FRIDAY. DURING THE WEEKEND THE HIGH WILL BECOME A STATIONARY
ELONGATED RIDGE THAT WILL STRETCH ALONG THE COAST FROM NEW ENGLAND
TO THE MID ATLANTIC STATES. THIS SHOULD KEEP FAIR AND DRY WEATHER
OVER THE FORECAST AREA FOR THE ENTIRE LONG TERM PERIOD. AT TIMES...
VARIOUS RUNS OF THE GFS/ECMWF HAVE INDICATED THE POSSIBILITY OF SCT
CONVECTION FRIDAY OR SATURDAY DUE TO SOME WEAK DISTURBANCES MOVING
INTO/THROUGH THE HIGH...BUT THEY HAVE NOT BEEN CONSISTENT WITH THIS
SO WILL CONTINUE TO IGNORE THE THREAT AND FORECAST DRY CONDITIONS
FOR NOW.
TEMPS WILL START THE LONG TERM PERIOD ON THE COOL SIDE...ESPECIALLY
AT NIGHT...BUT THEN WARM TO ABOVE NORMAL READINGS BY FRIDAY AND THE
WEEKEND. LOWS WEDNESDAY NIGHT WILL BE IN THE UPPER 30S AND 40S.
HIGHS THURSDAY IN THE 60S TO LOWER 70S. LOWS THURSDAY NIGHT IN THE
MID 30S TO MID 40S. HIGHS FRIDAY IN THE MID 60S TO MID 70S. LOWS
FRIDAY NIGHT IN THE UPPER 30S AND 40S. HIGHS SATURDAY IN THE UPPER
60S AND 70S. LOWS SATURDAY NIGHT IN THE 40S AND LOWER 50S...AND
HIGHS SUNDAY IN THE 70S.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
A FRONTAL BOUNDARY WILL BE NEARLY STATIONARY SOMEWHERE ACROSS
SOUTHEAST NEW YORK AS LOW PRESSURE COMES SLOWLY UP THE APPALACHIAN
CHAIN TODAY THROUGH TUESDAY. INITIALLY WIDESPREAD LIGHT RAIN WILL BE
OVER THE REGION THIS MORNING WITH A BREAK IN THE PCPN FOR PART OF
THIS AFTERNOON POSSIBLE AS RADAR IMAGERY AT 630 AM SHOWS A LARGE
AREA OF LITTLE OR NO RAIN OVER ERN PA AND NJ. AS A RESULT...MAINLY
VFR CONDITIONS EXPECTED AT THE KGFL/KALB/KPOU TAF SITES FOR MOST OF
TODAY...WHILE MVFR/IFR VSBY CONDITIONS WILL OCCUR AT KPSF WHERE THE
LOWER VSBYS ARE PRIMARILY DUE TO FOG (CIGS WILL BE MAINLY
VFR).
DURING THE EARLY AND MIDDLE PART OF THE AFTERNOON...AS NOTED ABOVE...
RAINFALL MAY END FOR A TIME OR BECOME SCATTERED. CONDITIONS LIKELY
TO BE MAINLY VFR AT ALL FOUR TAF SITES. HOWEVER...AS THE HEAVIER
RAIN ARRIVES LATER THIS AFTERNOON...CONDITIONS WILL LOWER TO MVFR AT
ALL THE TAF SITES INTO THE VENING...THEN ALL SITES WILL HAVE
WIDESPREAD IFR CONDITIONS BY MIDNIGHT...WITHTHE WIDESPREAD IFR
CONDITIONS CONTINUING THROUGH THE END OF THE TAF PERIOD AT 12Z
TUESDAY.
SURFACE WINDS WILL BE CALM OR LIGHT NORTHERLY (5 KTS OR LESS) TO
START THE TAF PERIOD...THEN SWITCH TO SOUTHERLY LATER THIS MORNING
AND PICK UP TO 5 TO 10 KTS DURING THE AFTERNOON. WINDS WILL REMAIN
SOUTHERLY TONIGHT...BUT DECREASE TO 5 KTS OR LESS.
.OUTLOOK...
TUE-TUE NGT...MVFR/IFR RA LIKELY.
WED...MAINLY VFR...SCT SHRA.
WED NGT-FRI...VFR...NO WX.
&&
.FIRE WEATHER...
DAMP CONDITIONS WILL PREVAIL TODAY IN MOST SECTIONS WITH SCATTERED
TO NUMEROUS SHOWERS. AREAS ACROSS THE ADIRONDACKS...MOHAWK VALLEY
AND LITCHFIELD COUNTY WILL LIKELY SEE RAINFALL AMOUNTS UNDER A
QUARTER OF AN INCH TODAY...WHILE OTHER REGIONS WILL HAVE A QUARTER
TO UPWARDS OF NEARLY HALF AN INCH.
RH VALUES WILL REMAIN ELEVATED TODAY...GENERALLY NO LOWER THAN 60-75
PERCENT.
A SOAKING RAIN IS IN THE OFFING LATER TONIGHT THROUGH TUESDAY NIGHT
WITH RAINFALL AMOUNTS RANGING FROM AROUND THREE QUARTERS OF INCH
ACROSS THE ADIRONDACKS...TO 1-3 INCHES ACROSS THE REMAINDER OF THE
REGION.
SOME DRYING IS EXPECTED WEDNESDAY...HOWEVER ADDITIONAL SHOWERS ARE
POSSIBLE.
MUCH DRIER WEATHER LOOKS LIKELY THURSDAY INTO NEXT WEEKEND.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE EXPECTED THROUGH TODAY.
IT STILL LOOKS AS IF TODAY/S RAINFALL WILL GENERALLY RANGE FROM A
QUARTER TO HALF AN INCH...WITH LIGHTER AMOUNTS UNDER A QUARTER OF AN
INCH ACROSS THE ADIRONDACKS...MOHAWK VALLEY AND LITCHFIELD COUNTY.
THIS RAIN WILL PRODUCE MINOR RISES ON STREAMS AND RIVERS AT THE
MOST.
THEN...IT LOOKS OF AS IF A MORE STEADY AND POTENTIALLY HEAVIER RAIN
WILL ENSUE TONIGHT INTO EARLY TUESDAY NIGHT. RAINFALL AMOUNTS STILL
LOOK TO BE IN ONE TO THREE INCH RANGE...EXCEPT A LITTLE LESS ACROSS
PORTIONS OF OUR ADIRONDACKS.
ASSUMING THIS RAINFALL AMOUNT WORKS OUT...THE ADIRONDACKS SHOULD
ONLY SEE ONLY ADDITIONAL MINOR RISES ON STREAMS AND RIVERS. OTHER
REGIONS WILL SEE MORE SIGNIFICANT WITHIN BANK RISES ON RIVERS AND
STREAMS...WITH MANY OF THEM POSSIBLY REACHING ACTION STAGE.
AGAIN...ASSUMING WE HAVE A GOOD HANDLE OF THE QPF AMOUNTS...FLOODING
IS NOT LIKELY AND THEREFORE NO FLOOD WATCHES WERE ISSUED WITH THIS
RAINFALL EVENT AT THIS TIME. IT WOULD BE A GOOD IDEA TO CHECK BACK
ON THE HYDROLOGY STATUS DURING THE NEXT COUPLE OF DAYS.
NEVERTHELESS...PONDING OF WATER IS A GOOD BET...MAINLY IN AREAS OF
POOR DRAINAGE AS RAINFALL RATES COULD REACH UP TO A QUARTER OF AN
INCH AN HOUR AT TIMES LATE TONIGHT INTO EARLY TUESDAY NIGHT.
SOME ADDITIONAL RAINFALL IS POSSIBLE ON WEDNESDAY WITH ANOTHER
FASTER MOVING COLD FRONT...BUT AT THIS POINT RIVER BASIN QPF WITH
THIS SYSTEM LOOKS TO BE UNDER A QUARTER OF AN INCH.
DRIER WEATHER IS THEN FORECAST LATE IN THE WEEK AND WEEKEND WHICH
WOULD ALLOW RIVERS AND STREAMS TO RECEDE BACK TO MORE SEASONAL
LEVELS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...HWJIV
AVIATION...GJM
FIRE WEATHER...HWJIV
HYDROLOGY...HWJIV
AREA FORECAST DISCUSSION
NWS ALBANY NY
635 AM EDT MON MAY 14 2012
.SYNOPSIS...
A STATIONARY FRONT WILL SERVE AS PATHWAY FOR SEVERAL DISTURBANCES TO
MOVE ALONG IT...STARTING TODAY...THROUGH TUESDAY NIGHT. TODAY
DISTURBANCES LOOK FAIRLY WEAK BRAINING SCATTERED TO NUMEROUS
SHOWERS. HOWEVER...A STRONGER DISTURBANCE TONIGHT WILL LIKELY BRING
A SOAKING POTENTIALLY HEAVY RAINFALL...TO MAINLY CENTRAL AND
SOUTHERN PORTIONS OF OUR REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 630 AM...BASED ON REGIONAL RADARS AND THE HRRR EXPERIMENTAL
MODEL...HAVE DECIDED TO GO BACK TO THE IDEA OF A MORE STEADIER RAIN
(ALBEIT LIGHT) THIS MORNING THEN A BREAK IN THE RAIN (SCATTERED
SHOWERS)DURING MUCH OF THE AFTERNOON. ACTUALLY...THE 00Z NAM
SUPPORTED THIS IDEA. THE 06Z GFS STILL BRINGS HEAVIER RAIN IN THIS
AFTERNOON...BUT AGAIN REGIONAL RADAR DOES NOT SUPPORT THIS IDEA.
TINKERED WITH THE QPF BUT NOT MUCH TO REFLECT THIS MODIFICATION IN
THINKING.
EITHER WAY...IT WILL REMAIN DAMP AND PROBABLY WILL SEE SCATTERED
SHOWERS OR PATCHY DRIZZLE THIS AFTERNOON ALONG WITH LOTS OF CLOUDS.
NO OTHER CHANGES OTHER THEN TO RE-TOOL THE HOURLY GRIDS...WHICH WERE
IN PRETTY GOOD SHAPE.
RAINFALL AMOUNTS LOOK TO BE A QUARTER TO MAYBE HALF AN
INCH...LIGHTER AMOUNTS UNDER QUARTER OF AN INCH TO THE NORTHWEST.
THE CLOUDS AND SHOWERS SHOULD KEEP TEMPERATURES DOWN
TODAY...GENERALLY HELD TO THE 60S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
CONFIDENCE IS NOW HIGHER THAT THE AXIS OF HEAVY RAIN TONIGHT THROUGH
TUESDAY NIGHT WILL GENERALLY RUN FROM THE CATSKILLS...NORTHEAST
ACROSS THE GREATER CAPITAL DISTRICT INTO THE SOUTHERN VERMONT.
THE SYNOPTIC SETUP DOES NOT REALLY LOOK LIKE A CLASSICAL HEAVY
RAINFALL EVENT...BUT CERTAINLY A MODERATE ONE. THE UPPER AIR TROUGH
IS SOMEWHAT WEAK. THERE WILL BE A LOW LEVEL JET...POSSIBLY
INCREASING TO 40KTS TRANSPORTING PWAT VALUES APPROACHING AN INCH AND
HALF FROM ALBANY SOUTHWARD. THE FLOW LOOKS TO BE SSE TO
SOUTHERLY...THROUGHOUT THE COLUMN.
A STRONGER DISTURBANCE...STILL DEVELOPING DOWN IN THE TENNESSEE
VALLEY...WILL BE THE ONE TO BRING MORE SIGNIFICANT RAINFALL TONIGHT
THROUGH TUESDAY NIGHT AS OUR CENTRAL AND EVENTUALLY SOUTHEAST AREAS
COME UNDERNEATH MID LEVEL FRONTOGENESIS AND ASSISTANCE FROM
DIVERGENCE ALOFT UNDERNEATH THE LEFT ENTRANCE OF AN UPPER LEVEL JET.
THE TOTAL QPF AMOUNT IS STILL SOMEWHAT UNCERTAIN AS THERE IS SOME
DISPARITY WITH THE CANADIAN AND EUROPEAN MODELS GENERALLY GIVING A
TOTAL RAINFALL IN THE 1-2 INCH RANGE...WHILE THE GFS AND NAM WERE
MORE IN THE 2-3+ INCH RANGE.
FOR NOW...PER HPC...HAVE LEANED WITH THE AMERICAN MODELS. MORE ABOUT
THE QPF AND WHAT IT COULD FOR OUR HYDROLOGICAL SERVICE AREAS (HSA)
CAN BE FOUND IN OUR HYDROLOGY SECTION.
SHOWALTER INDICES REMAINED POSITIVE WITH VERY LITTLE IF ANY SURFACE
INSTABILITY THROUGH TONIGHT. ON TUESDAY SHOWALTER VALUES LOOK TO
APPROACH ZERO SO WE WILL INCLUDE A SLIGHT CHANCE OF THUNDER.
THE UPPER LEVEL TROUGH LOOKS TO BEGIN TO SLOWLY SHIFT EASTWARD
TUESDAY TAKING THE SURFACE FRONT WITH IT AS IT GETS A KICK FROM
ANOTHER UPSTREAM DISTURBANCE. THE MODERATE TO HEAVY RAIN WILL SHIFT
EASTWARD AS WELL...AND FINALLY END.
HOWEVER...THE "KICKER"...ANOTHER COLD FRONT...COULD PRODUCE A ROUND
OF SHOWERS AND EVEN THUNDERSTORMS OF ITS OWN WEDNESDAY. THIS LOOKS
TO BE A MUCH FASTER MOVING SYSTEM SO ANY PRECIPITATION WITH IT
SHOULD NOT BE NEARLY AS HEAVY OR PROLONGED.
WITH CLOUDS AND RAIN...THERE WILL BE VERY LITTLE RANGE IN DIURNAL
TEMPERATURES THROUGH TUESDAY NIGHT. OVERNIGHT LOWS WILL BE IN THE
50S TO AROUND 60 AND DAYTIME HIGHS IN THE 60S.
BY WEDNESDAY...WE EXPECT BREAKS OF SUNSHINE MIDDAY AND AFTERNOON
ALONG WITH CONTINUE H850 TEMPERATURES NOT FAR FROM +10C.
THEREFORE...LOOK FOR A BOUNCE IN TEMPERATURES AS THEY RISE BACK
THROUGH THE 70S...POSSIBLY TOUCHING 80 IN SOME OF THE WARMEST SPOTS
MAINLY SOUTH OF ALBANY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A LARGE HIGH PRESSURE SYSTEM WILL BEGIN BUILDING EAST FROM THE GREAT
LAKES REGION WEDNESDAY NIGHT...AND BE OVER THE REGION THURSDAY NIGHT
AND FRIDAY. DURING THE WEEKEND THE HIGH WILL BECOME A STATIONARY
ELONGATED RIDGE THAT WILL STRETCH ALONG THE COAST FROM NEW ENGLAND
TO THE MID ATLANTIC STATES. THIS SHOULD KEEP FAIR AND DRY WEATHER
OVER THE FORECAST AREA FOR THE ENTIRE LONG TERM PERIOD. AT TIMES...
VARIOUS RUNS OF THE GFS/ECMWF HAVE INDICATED THE POSSIBILITY OF SCT
CONVECTION FRIDAY OR SATURDAY DUE TO SOME WEAK DISTURBANCES MOVING
INTO/THROUGH THE HIGH...BUT THEY HAVE NOT BEEN CONSISTENT WITH THIS
SO WILL CONTINUE TO IGNORE THE THREAT AND FORECAST DRY CONDITIONS
FOR NOW.
TEMPS WILL START THE LONG TERM PERIOD ON THE COOL SIDE...ESPECIALLY
AT NIGHT...BUT THEN WARM TO ABOVE NORMAL READINGS BY FRIDAY AND THE
WEEKEND. LOWS WEDNESDAY NIGHT WILL BE IN THE UPPER 30S AND 40S.
HIGHS THURSDAY IN THE 60S TO LOWER 70S. LOWS THURSDAY NIGHT IN THE
MID 30S TO MID 40S. HIGHS FRIDAY IN THE MID 60S TO MID 70S. LOWS
FRIDAY NIGHT IN THE UPPER 30S AND 40S. HIGHS SATURDAY IN THE UPPER
60S AND 70S. LOWS SATURDAY NIGHT IN THE 40S AND LOWER 50S...AND
HIGHS SUNDAY IN THE 70S.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
A FRONTAL BOUNDARY WILL BECOME STATIONARY SOMEWHERE ACROSS SOUTHEAST
NEW YORK AS LOW PRESSURE COMES SLOWLY UP THE APPALACHIAN CHAIN TO
INITIALLY BRING WIDESPREAD LIGHT RAIN INTO THE REGION BY AROUND
DAYBREAK. THE RAIN WILL REMAIN LIGHT THROUGH MOST OF MONDAY WITH
CIG/VSBY CONDITIONS REMAINING VFR AT THE KGFL/KALB/KPOU/KPSF TAF
SITES THROUGH JUST BEFORE NOON MONDAY. DURING MONDAY AFTERNOON
CONDITIONS WILL DETERIORATE TO MAINLY MVFR CIGS BUT VSBY WILL LIKELY
REMAIN 6 MILES OR MORE. BETWEEN 22Z AND 02Z PCPN WILL BECOME HEAVIER
AND VSBYS WILL LOWER TO AROUND 3 MILES WHILE CIGS DROP TO 1000 FEET
OR LESS. THE MVFR/IFR CONDITIONS WILL THEN PERSIST THROUGH THE END
OF THE TAF PERIOD AT 06Z TUESDAY.
SURFACE WINDS WILL BE CALM OR LIGHT NORTHERLY (5 KTS OR LESS) TO
START THE TAF PERIOD...THEN SWITCH TO SOUTHERLY MONDAY MORNING AND
PICK UP TO 5 TO 10 KTS DURING THE AFTERNOON. WINDS WILL REMAIN
SOUTHERLY MONDAY NIGHT...BUT DECREASE TO 5 KTS OR LESS.
.OUTLOOK...
LATE MON NGT-TUE NGT...MVFR/IFR RA LIKELY.
WED...MAINLY VFR...SCT SHRA.
WED NGT-FRI...VFR...NO WX.
&&
.FIRE WEATHER...
DAMP CONDITIONS WILL PREVAIL TODAY IN MOST SECTIONS WITH SCATTERED
TO NUMEROUS SHOWERS. AREAS ACROSS THE ADIRONDACKS...MOHAWK VALLEY
AND LITCHFIELD COUNTY WILL LIKELY SEE RAINFALL AMOUNTS UNDER A
QUARTER OF AN INCH TODAY...WHILE OTHER REGIONS WILL HAVE A QUARTER
TO UPWARDS OF NEARLY HALF AN INCH.
RH VALUES WILL REMAIN ELEVATED TODAY...GENERALLY NO LOWER THAN 60-75
PERCENT.
A SOAKING RAIN IS IN THE OFFING LATER TONIGHT THROUGH TUESDAY NIGHT
WITH RAINFALL AMOUNTS RANGING FROM AROUND THREE QUARTERS OF INCH
ACROSS THE ADIRONDACKS...TO 1-3 INCHES ACROSS THE REMAINDER OF THE
REGION.
SOME DRYING IS EXPECTED WEDNESDAY...HOWEVER ADDITIONAL SHOWERS ARE
POSSIBLE.
MUCH DRIER WEATHER LOOKS LIKELY THURSDAY INTO NEXT WEEKEND.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE EXPECTED THROUGH TODAY.
IT STILL LOOKS AS IF TODAY/S RAINFALL WILL GENERALLY RANGE FROM A
QUARTER TO HALF AN INCH...WITH LIGHTER AMOUNTS UNDER A QUARTER OF AN
INCH ACROSS THE ADIRONDACKS...MOHAWK VALLEY AND LITCHFIELD COUNTY.
THIS RAIN WILL PRODUCE MINOR RISES ON STREAMS AND RIVERS AT THE
MOST.
THEN...IT LOOKS OF AS IF A MORE STEADY AND POTENTIALLY HEAVIER RAIN
WILL ENSUE TONIGHT INTO EARLY TUESDAY NIGHT. RAINFALL AMOUNTS STILL
LOOK TO BE IN ONE TO THREE INCH RANGE...EXCEPT A LITTLE LESS ACROSS
PORTIONS OF OUR ADIRONDACKS.
ASSUMING THIS RAINFALL AMOUNT WORKS OUT...THE ADIRONDACKS SHOULD
ONLY SEE ONLY ADDITIONAL MINOR RISES ON STREAMS AND RIVERS. OTHER
REGIONS WILL SEE MORE SIGNIFICANT WITHIN BANK RISES ON RIVERS AND
STREAMS...WITH MANY OF THEM POSSIBLY REACHING ACTION STAGE.
AGAIN...ASSUMING WE HAVE A GOOD HANDLE OF THE QPF AMOUNTS...FLOODING
IS NOT LIKELY AND THEREFORE NO FLOOD WATCHES WERE ISSUED WITH THIS
RAINFALL EVENT AT THIS TIME. IT WOULD BE A GOOD IDEA TO CHECK BACK
ON THE HYDROLOGY STATUS DURING THE NEXT COUPLE OF DAYS.
NEVERTHELESS...PONDING OF WATER IS A GOOD BET...MAINLY IN AREAS OF
POOR DRAINAGE AS RAINFALL RATES COULD REACH UP TO A QUARTER OF AN
INCH AN HOUR AT TIMES LATE TONIGHT INTO EARLY TUESDAY NIGHT.
SOME ADDITIONAL RAINFALL IS POSSIBLE ON WEDNESDAY WITH ANOTHER
FASTER MOVING COLD FRONT...BUT AT THIS POINT RIVER BASIN QPF WITH
THIS SYSTEM LOOKS TO BE UNDER A QUARTER OF AN INCH.
DRIER WEATHER IS THEN FORECAST LATE IN THE WEEK AND WEEKEND WHICH
WOULD ALLOW RIVERS AND STREAMS TO RECEDE BACK TO MORE SEASONAL
LEVELS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...HWJIV
AVIATION...GJM
FIRE WEATHER...HWJIV
HYDROLOGY...HWJIV
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
935 PM EDT TUE MAY 15 2012
.UPDATE (TONIGHT AND WEDNESDAY)...
01Z WATER VAPOR AND H4 RUC ANALYSIS SHOWS AN AMPLIFIED UPPER LEVEL
PATTERN OVER THE CONUS THIS EVENING WITH NORTHERN STREAM FLOW
CONFIGURED INTO BROAD RIDGING FROM THE PACIFIC NORTHWEST THROUGH
SOUTH-CENTRAL CANADA...AND THEN CARVING OUT LONGWAVE TROUGHING
ACROSS THE EASTERN HALF OF THE NATION. THE DEEP TROUGHING INTO THE
GULF OF MEXICO FOR THIS TIME OF YEAR IS PROVIDING RATHER ROBUST
UPPER LEVEL FLOW HIGH ABOVE THE EASTERN GULF AND FL PENINSULA. THIS
FLOW IS PROVIDING PLENTY OF MID/UPPER LEVEL COLUMN MOISTURE AND ALSO
THE POTENTIAL FOR PERIODIC SUBTLE IMPULSES TO MOVE OVER THE REGION.
THESE TWO FEATURES COMBINED WITH THE FAVORABLE UPPER LEVEL JET
CONFIGURATION WILL LIKELY KEEP THE THREAT FOR SCATTERED
SHOWERS/STORM IN THE FORECAST THROUGH THE MIDDLE OF THE WEEK. AS
USUAL FOR THIS TIME OF YEAR...THE BEST CHANCES/HIGHEST COVERAGE OF
THIS CONVECTION WILL BE INLAND FROM THE COAST AND MAXIMIZED DURING
THE AFTERNOON/EVENING HOURS.
AT THE SURFACE...A WEAK SUBTROPICAL RIDGE AXIS IS ANALYZED DOWN OVER
THE FAR SOUTHERN FL PENINSULA/FL STRAITS THIS EVENING...WITH A BROAD
INVERTED TROUGH EXTENDING NORTHWARD FROM THE YUCATAN PENINSULA INTO
THE CENTRAL GULF OF MEXICO. OVERALL THE LOCAL GRADIENT AROUND THESE
FEATURES IS QUITE WEAK AND WILL KEEP OUR SYNOPTIC FLOW ON THE LIGHT
SIDE THROUGH WEDNESDAY.
REST OF TONIGHT...RESIDUAL CONVERGENCE BETWEEN THE WEST COAST
SEA-BREEZE AND CONVECTIVE OUTFLOW IS STILL TRIGGERING A FEW SHOWERS
INLAND FROM THE I-75 CORRIDOR FROM NEAR FT. MYERS TO CENTRAL POLK
COUNTY. THIS LEFTOVER ACTIVITY SHOULD FADE IN THE NEXT HOUR OR 2 AS
THE LOSS OF DIURNAL HEATING SLOWLY SHUTS DOWN THE SEA-BREEZE
CIRCULATION. LATER TONIGHT THROUGH WEDNESDAY MORNING...WILL BE
WATCHING FOR ANY OF THE PRE-MENTIONED SUBTLE IMPULSES WHICH WOULD
HAVE THE POTENTIAL TO BRING A ROUND OF SHOWERS TOWARD THE COAST FROM
THE EASTERN GULF...HOWEVER NOTHING IMMINENT IS CURRENTLY ANALYZED IN
WV IMAGERY.
&&
.AVIATION...
MID LEVEL CIGS AOA 120 OVER SOUTHWEST FLORIDA THIS EVENING WITH A
SLIGHT CHANCE OF A SHOWER...OTHERWISE VFR CONDITIONS PREVAIL WITH
SCT LCL BKN250. INCREASING HIGH CLOUDINESS OVERNIGHT WITH SCT
SHOWERS WITH LCL MVFR CIGS/VSBYS DEVELOPING VCNTY ALL TERMINALS
WEDNESDAY MORNING. SCT TSTMS WILL DEVELOP DURING THE AFTERNOON AND
PUSH INLAND WITH LCL IFR CIGS/VSBYS...OUTSIDE OF SHOWER ACTIVITY VFR
CONDITIONS WILL PREVAIL. BEST CHANCE OF THUNDERSTORMS WEDNESDAY
WILL BE OVER THE INTERIOR NEAR LAL.
&&
.MARINE...
WEAK SURFACE HIGH PRESSURE WILL CONTINUE TO SUPPORT LIGHT WINDS AND
SLIGHT SEAS OVER THE GULF WATERS TONIGHT THROUGH THE REMAINDER OF
THE WORK WEEK WITH AN ENHANCED ONSHORE SEA BREEZE COMPONENT
DEVELOPING ALONG THE COAST EACH AFTERNOON. WIND AND SEAS WILL BE ON
THE INCREASE BY THE UPCOMING WEEKEND AS THE GRADIENT TIGHTENS IN
RESPONSE TO A STRONGER SURFACE HIGH BUILDING DOWN THE EASTERN SEA
BOARD WITH EXERCISE CAUTION OR LOW END SMALL CRAFT CONDITIONS A
POSSIBILITY BY LATE SATURDAY INTO SUNDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 72 87 72 87 / 20 50 20 50
FMY 72 87 71 86 / 20 50 20 50
GIF 72 90 71 89 / 20 60 20 60
SRQ 71 86 70 86 / 20 50 20 50
BKV 64 88 63 88 / 20 50 20 50
SPG 74 86 74 86 / 20 50 20 50
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
MROCZKA/OGLESBY
AREA FORECAST DISCUSSION
NWS MIAMI FL
156 PM EDT MON MAY 14 2012
.AVIATION...VFR WILL PREVAIL. SHRA/TSRA WILL CONCENTRATE OVER THE
INTERIOR, BUT COULD MOVE TOWARDS KPBI LATER THIS AFTERNOON.
TRANQUIL WEATHER IS EXPECTED OVERNIGHT. TSRA IS A BETTER BET FOR
THE EAST COAST TERMINALS ON TUE AFTERNOON. ADDED VCTS THERE FOR
NOW, BUT TEMPO WILL LIKELY BE NEEDED AT LATER FORECAST ISSUANCES.
/GREGORIA
&&
.PREV DISCUSSION... /ISSUED 924 AM EDT MON MAY 14 2012/
UPDATE...
THE MORNING SURFACE ANALYSIS SHOWED A RIDGE AXIS EXTENDING WEST
OVER CENTRAL FLORIDA WITH LIGHT SOUTHEAST LOW-LEVEL FLOW STREAMING
ACROSS SOUTH FLORIDA. A COLD FRONT WAS ANALYZED OVER THE GULF
EXTENDING SOUTH FROM THE FL PANHANDLE TO THE SOUTHWEST GULF OF
MEXICO. RECENTLY ANIMATED WATER VAPOR LOOP SHOWED A POSITIVELY-
TILTED UPPER TROUGH EXTENDING SOUTHWEST OVER THE PLAINS AND A
RIDGE AXIS EXTENDING NORTH OVER THE WESTERN ATLANTIC. THIS PLACES
SOUTH FLORIDA UNDER PRIMARILY MOIST SOUTHWEST MID TO UPPER FLOW. A
WEAK SHORTWAVE TROUGH EMBEDDED WITHIN THIS SOUTHWEST FLOW
APPROACHING FROM THE WEST COMBINED WITH SUFFICIENT DAYTIME HEATING
AND INSTABILITY WILL BE ENOUGH TO INITIATE AFTERNOON CONVECTION
ACROSS PORTIONS OF THE LOCAL AREA TODAY. THE LATEST HRRR AND WRF
SOLUTIONS ARE IN DECENT AGREEMENT AND GENERALLY INDICATE THE
AFTERNOON CONVECTION SETTING UP OVER THE INTERIOR LOCATIONS AND
FARTHER NORTH AROUND THE LAKE AND PALM BEACH COUNTY AREA THROUGH
THE EVENING HOURS BEFORE TRENDING DOWN TONIGHT. THIS LINES UP
WELL WITH THE LATEST FORECAST PACKAGE AND ONLY SLIGHT
MODIFICATIONS WERE NEEDED IN THE HAZARDOUS WEATHER OUTLOOK THIS
MORNING TO INCLUDE THE POTENTIAL FOR STRONG WIND GUSTS AND SMALL
HAIL WITH ANY STORMS THAT BECOME STRONG TODAY. OTHERWISE...THE
PREVIOUS FORECAST PACKAGE REMAINS ON TRACK AND NO OTHER UPDATES
WERE NECESSARY AT THIS TIME. 85/AG
PREV DISCUSSION... /ISSUED 724 AM EDT MON MAY 14 2012/
AVIATION...VFR CONDITIONS WILL PREVAIL THROUGH AT LEAST 16Z WITH EXTENSIVE
CIRRUS FIELD ACROSS S FL. CONVECTION IS EXPECTED TO DEVELOP AFT 16Z
ACROSS THE INTERIOR AND STEERING FLOW WILL TAKE IT TO THE NNE SO
MOSTLY AFFECT THE KPBI TERMINAL. HOWEVER, CANNOT RULE OUT THE
POSSIBILITY OF DEVELOPMENT FARTHER TO THE SOUTH AS THE AFTERNOON
PROGRESSES BUT CONFIDENCE NOT HIGH TO PLACE IN THE TAFS. LIGHT SE
SFC WIND WILL CONTINUE THROUGH THE PERIOD ALLOWING FOR W CST SEA
BREEZE AFT 18Z.
PREV DISCUSSION... /ISSUED 315 AM EDT MON MAY 14 2012/
DISCUSSION...BROAD UPPER TROUGH OVER THE EASTERN 2/3RDS OF THE U.S.
DEEPENS AS A SHORT WAVE MOVES INTO THE TROUGH FROM THE SOUTHERN
ROCKIES. THE TROUGH MOVES SLOWLY EASTWARD AND BY THURSDAY MORNING
WILL BE ALIGNED WITH THE E U.S. COAST AND EXTEND SW ACROSS THE FLA
PANHANDLE INTO THE N GULF OF MEX. AS THE TROUGH MOVES E AND OFFSHORE
INTO THE ATLC...A CLOSED LOW WILL DEVELOP OFF OF THE SE U.S. COAST
LATE THURSDAY NIGHT AND PERSIST INTO NEXT WEEKEND. AT THE
SURFACE...A SURFACE LOW IN THE SOUTHERN APPALACHIANS ALONG THE
SURFACE TROUGH ASSOCIATED WITH THE UPPER TROUGH WILL GET TO THE E
U.S. COAST AND THE FLA PANHANDLE BY WEDNESDAY NIGHT AS THE SURFACE
LOW MOVES INTO THE MID ATLC STATES. THE TROUGH WILL MOVE SE AND
THROUGH S FLA THURSDAY AND WILL BE SE OF THE AREA FRIDAY AND
SATURDAY. FINALLY THE ECWMF AND GFS INTO SIMILAR AGREEMENT.
FOR THE SHORT TERM...TODAY THROUGH WEDNESDAY...AS THE UPPER TROUGH
DEEPENS...WINDS ALOFT BECOME SW PULLING SOME DEEPER MOISTURE OVER S
FLA. AT THE LOWER LEVELS WINDS WILL BE SE BUT LIGHT ALLOWING E/W
COAST SEA BREEZES. COMBINED WITH HEATING...AN INCREASE IN SHOWERS
/MAINLY AFTERNOON THUNDERSTORMS CAN BE EXPECTED. WITH THE STEERING
WINDS ALOFT SW...THE CONVECTIVE ACTIVITY WILL AFFECT THE INTERIOR
AND NE COASTAL AREAS THOUGH ALL ZONES WILL SEE SOME RAINFALL. THIS
PATTERN WILL PERSIST EACH DAY WITH NOCTURNAL ACTIVITY POSSIBLE...
MAINLY OFF OF THE E COAST IN THE EVENING AND THE W COAST OVER
-NIGHT.
EXTENDED FORECAST...THURSDAY THROUGH SUNDAY...LITTLE CHANGE
THURSDAY THOUGH STEERING WINDS BECOME A LITTLE MORE NW AFFECTING THE
E COAST UNIFORMLY WITH CONVECTION. WITH AN UPPER CLOSED LOW
DEVELOPING OFF OF THE SE U.S. COAST FRIDAY AND INTO SATURDAY...AND
WITH THE SURFACE TROUGH SE OF THE AREA...DRIER AIR WILL MOVE OVER S
FLA WITH POPS DROPPING DRASTICALLY. VERY LITTLE...IF AT ALL...
LOWERING OF MAX/MIN TEMPERATURES EXPECTED.
MARINE...
WINDS 10 KNOTS OR LESS TONIGHT THROUGH FRIDAY THOUGH SHIFTING FROM
SOUTHERLY TO NORTHERLY THURSDAY AS THE TROUGH MOVES THROUGH. SEAS 2
FEET OR LESS AS WELL.
FIRE WEATHER...
RELATIVE HUMIDITY VALUES REMAIN ABOVE 35 PERCENT CRITICAL VALUE
THROUGH MID WEEK. NO PROBLEMS EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 84 74 84 72 / 50 40 60 40
FORT LAUDERDALE 84 75 85 74 / 40 30 60 40
MIAMI 85 73 86 72 / 30 30 60 30
NAPLES 86 72 85 72 / 30 20 30 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MIAMI FL
924 AM EDT MON MAY 14 2012
.UPDATE...
THE MORNING SURFACE ANALYSIS SHOWED A RIDGE AXIS EXTENDING WEST
OVER CENTRAL FLORIDA WITH LIGHT SOUTHEAST LOW-LEVEL FLOW STREAMING
ACROSS SOUTH FLORIDA. A COLD FRONT WAS ANALYZED OVER THE GULF
EXTENDING SOUTH FROM THE FL PANHANDLE TO THE SOUTHWEST GULF OF
MEXICO. RECENTLY ANIMATED WATER VAPOR LOOP SHOWED A POSITIVELY-
TILTED UPPER TROUGH EXTENDING SOUTHWEST OVER THE PLAINS AND A
RIDGE AXIS EXTENDING NORTH OVER THE WESTERN ATLANTIC. THIS PLACES
SOUTH FLORIDA UNDER PRIMARILY MOIST SOUTHWEST MID TO UPPER FLOW. A
WEAK SHORTWAVE TROUGH EMBEDDED WITHIN THIS SOUTHWEST FLOW
APPROACHING FROM THE WEST COMBINED WITH SUFFICIENT DAYTIME HEATING
AND INSTABILITY WILL BE ENOUGH TO INITIATE AFTERNOON CONVECTION
ACROSS PORTIONS OF THE LOCAL AREA TODAY. THE LATEST HRRR AND WRF
SOLUTIONS ARE IN DECENT AGREEMENT AND GENERALLY INDICATE THE
AFTERNOON CONVECTION SETTING UP OVER THE INTERIOR LOCATIONS AND
FARTHER NORTH AROUND THE LAKE AND PALM BEACH COUNTY AREA THROUGH
THE EVENING HOURS BEFORE TRENDING DOWN TONIGHT. THIS LINES UP
WELL WITH THE LATEST FORECAST PACKAGE AND ONLY SLIGHT
MODIFICATIONS WERE NEEDED IN THE HAZARDOUS WEATHER OUTLOOK THIS
MORNING TO INCLUDE THE POTENTIAL FOR STRONG WIND GUSTS AND SMALL
HAIL WITH ANY STORMS THAT BECOME STRONG TODAY. OTHERWISE...THE
PREVIOUS FORECAST PACKAGE REMAINS ON TRACK AND NO OTHER UPDATES
WERE NECESSARY AT THIS TIME. 85/AG
&&
.PREV DISCUSSION... /ISSUED 724 AM EDT MON MAY 14 2012/
AVIATION...VFR CONDITIONS WILL PREVAIL THROUGH AT LEAST 16Z WITH EXTENSIVE
CIRRUS FIELD ACROSS S FL. CONVECTION IS EXPECTED TO DEVELOP AFT 16Z
ACROSS THE INTERIOR AND STEERING FLOW WILL TAKE IT TO THE NNE SO
MOSTLY AFFECT THE KPBI TERMINAL. HOWEVER, CANNOT RULE OUT THE
POSSIBILITY OF DEVELOPMENT FARTHER TO THE SOUTH AS THE AFTERNOON
PROGRESSES BUT CONFIDENCE NOT HIGH TO PLACE IN THE TAFS. LIGHT SE
SFC WIND WILL CONTINUE THROUGH THE PERIOD ALLOWING FOR W CST SEA
BREEZE AFT 18Z.
PREV DISCUSSION... /ISSUED 315 AM EDT MON MAY 14 2012/
DISCUSSION...BROAD UPPER TROUGH OVER THE EASTERN 2/3RDS OF THE U.S.
DEEPENS AS A SHORT WAVE MOVES INTO THE TROUGH FROM THE SOUTHERN
ROCKIES. THE TROUGH MOVES SLOWLY EASTWARD AND BY THURSDAY MORNING
WILL BE ALIGNED WITH THE E U.S. COAST AND EXTEND SW ACROSS THE FLA
PANHANDLE INTO THE N GULF OF MEX. AS THE TROUGH MOVES E AND OFFSHORE
INTO THE ATLC...A CLOSED LOW WILL DEVELOP OFF OF THE SE U.S. COAST
LATE THURSDAY NIGHT AND PERSIST INTO NEXT WEEKEND. AT THE
SURFACE...A SURFACE LOW IN THE SOUTHERN APPALACHIANS ALONG THE
SURFACE TROUGH ASSOCIATED WITH THE UPPER TROUGH WILL GET TO THE E
U.S. COAST AND THE FLA PANHANDLE BY WEDNESDAY NIGHT AS THE SURFACE
LOW MOVES INTO THE MID ATLC STATES. THE TROUGH WILL MOVE SE AND
THROUGH S FLA THURSDAY AND WILL BE SE OF THE AREA FRIDAY AND
SATURDAY. FINALLY THE ECWMF AND GFS INTO SIMILAR AGREEMENT.
FOR THE SHORT TERM...TODAY THROUGH WEDNESDAY...AS THE UPPER TROUGH
DEEPENS...WINDS ALOFT BECOME SW PULLING SOME DEEPER MOISTURE OVER S
FLA. AT THE LOWER LEVELS WINDS WILL BE SE BUT LIGHT ALLOWING E/W
COAST SEA BREEZES. COMBINED WITH HEATING...AN INCREASE IN SHOWERS
/MAINLY AFTERNOON THUNDERSTORMS CAN BE EXPECTED. WITH THE STEERING
WINDS ALOFT SW...THE CONVECTIVE ACTIVITY WILL AFFECT THE INTERIOR
AND NE COASTAL AREAS THOUGH ALL ZONES WILL SEE SOME RAINFALL. THIS
PATTERN WILL PERSIST EACH DAY WITH NOCTURNAL ACTIVITY POSSIBLE...
MAINLY OFF OF THE E COAST IN THE EVENING AND THE W COAST OVER
-NIGHT.
EXTENDED FORECAST...THURSDAY THROUGH SUNDAY...LITTLE CHANGE
THURSDAY THOUGH STEERING WINDS BECOME A LITTLE MORE NW AFFECTING THE
E COAST UNIFORMLY WITH CONVECTION. WITH AN UPPER CLOSED LOW
DEVELOPING OFF OF THE SE U.S. COAST FRIDAY AND INTO SATURDAY...AND
WITH THE SURFACE TROUGH SE OF THE AREA...DRIER AIR WILL MOVE OVER S
FLA WITH POPS DROPPING DRASTICALLY. VERY LITTLE...IF AT ALL...
LOWERING OF MAX/MIN TEMPERATURES EXPECTED.
MARINE...
WINDS 10 KNOTS OR LESS TONIGHT THROUGH FRIDAY THOUGH SHIFTING FROM
SOUTHERLY TO NORTHERLY THURSDAY AS THE TROUGH MOVES THROUGH. SEAS 2
FEET OR LESS AS WELL.
FIRE WEATHER...
RELATIVE HUMIDITY VALUES REMAIN ABOVE 35 PERCENT CRITICAL VALUE
THROUGH MID WEEK. NO PROBLEMS EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 84 73 85 72 / 50 40 50 40
FORT LAUDERDALE 84 74 85 75 / 40 30 50 40
MIAMI 85 74 86 74 / 30 30 50 30
NAPLES 86 70 86 71 / 30 20 30 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...85/AG
AVIATION/RADAR...57/DG
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
454 PM EDT MON MAY 14 2012
.SYNOPSIS...
LOW PRESSURE AND AN ASSOCIATED COLD FRONT WILL SLOWLY MOVE EAST
ACROSS THE REGION THROUGH TONIGHT. HIGH MOISTURE WILL CONTINUE AHEAD
OF THIS SYSTEM. SOME DRYING IS EXPECTED TUESDAY WHICH WILL RESULT
IN SCATTERED AFTERNOON SHOWERS AND THUNDERSTORMS THROUGH MIDWEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
UPPER TROUGH STILL TO THE WEST PULLING MOISTURE ACROSS THE REGION
FROM THE SOUTH. BOTH OBSERVED AND FORECAST SOUNDINGS ARE NEARLY
MOIST ADIABATIC WHICH SHOULD ALLOW SHOWERS TO POP UP WITH THE
SLIGHTEST TRIGGER. RUC13 SHOWS WEAK TROUGH ACROSS THE REGION LATE
THIS AFTERNOON INTO THE EARLY EVENING HOURS. ALSO...STRONG
AFTERNOON SURFACE HEATING HAS ALLOW STRONG AND IN SOME CASES NEAR
SEVERE THUNDERSTORM ACTIVITY TO DEVELOP MAINLY IN THE SOUTHERN
PART OF THE FORECAST AREA. EXPECT RAINFALL AMOUNTS TO REMAIN ONE
QUARTER INCH OR LESS IN THE WESTERN MIDLANDS AND TAPER TO LESS
THAN A TENTH OF AN INCH OVER THE EASTERN MIDLANDS THROUGH THIS
AFTERNOON...MAINLY DUE TO A LACK OF FORCING.
TONIGHT...THE UPPER TROUGH WILL BE SLOW MOVING AS IT MOVES INTO
THE REGION AND WILL CONTINUE TO PROVIDE UPPER SUPPORT
OVERNIGHT...ESPECIALLY DURING THE EVENING HOURS...THEREFORE WILL
CONTINUE WITH LIKELY POPS OVERNIGHT. THE PRECIPITABLE WATER AXIS
SHIFTS OVER THE FORECAST AREA OVERNIGHT AND EXPECT THE BEST
RAINFALL ACCUMULATION TO OCCUR DURING THIS PERIOD. THE WESTERN AND
NORTHERN MIDLANDS WILL LIKELY SEE THE HIGHEST AMOUNTS...POSSIBLY
UP TO AN INCH...BUT THE ENTIRE FORECAST AREA SHOULD SEE MODERATE
MEASURABLE RAINFALL THROUGH EARLY MONDAY MORNING. TEMPERATURES
TONIGHT WILL BE LIMITED BY INCREASED DEWPOINTS AND CLOUDS AND
PRECIPITATION...GENERALLY IN THE MID 60S.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY/...
SURFACE TROUGH WILL REMAIN ACROSS THE AREA THROUGH THE PERIOD AND
SHOULD PROVIDE FOCUS FOR SCATTERED SHOWERS AND THUNDERSTORMS.
AIR MASS APPEARS TO REMAIN MODERATELY MOIST AND INCREASINGLY UNSTABLE THROUGH
THE PERIOD. SOME DRYING SUGGESTED BY MODELS ESPECIALLY GFS...HOWEVER
EXPECT PRECIPITABLE WATER TO REMAIN RELATIVELY HIGH...NEAR 1.5
INCHES AT TIMES WITH PERSISTENT SOUTHWEST MOIST 850MB FLOW AHEAD
OF UPPER LEVEL TROUGH ACROSS THE MISSISSIPPI VALLEY AND MIDWEST.
SEVERAL SHORT WAVE TRIGGERS LIKELY TO ROTATE THROUGH THE
REGION...WHICH SHOULD AID THUNDERSTORM DEVELOPMENT...HOWEVER
TIMING OF WAVES DIFFICULT. FORECAST HIGH CHANCE POPS DURING THE
LATE AFTERNOON AND EVENING TUESDAY...POSSIBLY LATE INTO TUESDAY
NIGHT ASSOCIATED WITH POSSIBLE STRONGER SHORT WAVE. CHANCE
WEDNESDAY ESPECIALLY EAST MIDLANDS WHERE DEEPER MOISTURE IS
AND STRONGER UPPER LEVEL FORCING IS LOCATED. TEMPERATURES SHOULD BE
WARMER TUESDAY AND WEDNESDAY WITH SOME BREAKS IN THE OVERCAST MID
MORNING THROUGH EARLY AFTERNOON.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
MEDIUM RANGE MODELS HAVE COME INTO REASONABLE AGREEMENT WITH
POTENTIAL COASTAL LOW OFF THE CAROLINA COAST DURING THE EXTENDED
FORECAST PERIODS. BOTH GFS/ECMWF PUSH THE TROUGH FAR ENOUGH OFF
THE COAST THAT CONFIDENCE HAS INCREASED THAT THE SYSTEM LIKELY
WILL NOT AFFECT THE FORECAST AREA VERY MUCH. HIGH PRESSURE BUILDS
DOWN THE EAST COAST THURSDAY AND FRIDAY AS AN UPPER RIDGE BUILDS
OVER THE LOWER MISSISSIPPI VALLEY NORTHWARD INTO THE OHIO VALLEY
FOR THE WEEKEND. THIS WILL YIELD DRY WEATHER OVER OUR AREA THROUGH
THE WEEKEND WITH NEAR NORMAL TEMPERATURES EXPECTED.
&&
.AVIATION /21Z MONDAY THROUGH SATURDAY/...
UPPER TROUGH STILL TO THE WEST OF THE FORECAST AREA BRINGING
PLENTY OF MOISTURE ON LOW LEVEL SOUTH TO SOUTHWEST WIND FLOW.
WITH REAL GOOD SURFACE HEATING WHERE CLOUDS HAVE BROKEN UP...
THERE IS A POTENTIAL FOR THUNDERSTORMS TO DEVELOP BUT WILL NOT
MENTION IN TAF SITES UNLESS ACTIVITY IS MOVING RIGHT AT TAF SITE.
RUC13 H5 SHOWS WEAK TROUGHINESS DURING THIS PERIOD...SO DECIDED
TO MENTION SHOWERS IN THE VICINITY FOR THE MOST PART. WILL GO
MAINLY VFR BUT BRIEF IFR TO MVFR CONDITIONS ARE POSSIBLE IN
SHOWERS AND THUNDERSTORMS. CAE 88D SHOWS MORE CONVECTION FIRING UP
BETWEEN AGS AND OGB. EXPECT ACTIVITY TO WEAKEN AS SUN GOES DOWN
AND SURFACE HEATING ENDS. AFTER MIDNIGHT...MOIST SOUTHWEST WIND
FLOW WILL CONTINUE IN THE LOWER LEVELS AND IT SHOULD FAVOR MORE
IFR STRATUS CEILING THAN IFR FOG. WILL GO MAINLY MVFR VSBYS WITH
FOG MOST LOCATIONS TUESDAY NEAR DAYBREAK BUT WILL HAVE LOWER IFR
VSBYS AT AGS AND OGB. AFTER 14Z TUESDAY MORNING...CONDITIONS
SHOULD HAVE IMPROVED TO VFR AGAIN BUT WILL KEEP SHOWER IN THE
VICINITY REMARKS AS MOISTURE AND UPPER FEATURES STILL SIMILAR TO
THOSE TODAY.
EXTENDED AVIATION OUTLOOK...WIDESPREAD MVFR TO IFR CONDITIONS
POSSIBLE AGAIN WEDNESDAY MORNING AS LOW PRESSURE SYSTEM SLOWLY MOVES
EAST.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...07
SHORT TERM...
LONG TERM...
AVIATION...07
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
150 PM EDT MON MAY 14 2012
.SYNOPSIS...
LOW PRESSURE AND AN ASSOCIATED COLD FRONT WILL SLOWLY MOVE EAST
ACROSS THE REGION THROUGH TONIGHT. HIGH MOISTURE WILL CONTINUE AHEAD
OF THIS SYSTEM. SOME DRYING IS EXPECTED TUESDAY WHICH WILL RESULT
IN SCATTERED AFTERNOON SHOWERS AND THUNDERSTORMS THROUGH MIDWEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPPER TROUGH STILL TO THE WEST PULLING MOISTURE ACROSS THE REGION
FROM THE SOUTH. BOTH OBSERVED AND FORECAST SOUNDINGS ARE NEARLY
MOIST ADIABATIC WHICH SHOULD ALLOW SHOWERS TO POP UP WITH THE
SLIGHTEST TRIGGER. RUC13 SHOWS WEAK TROUGH ACROSS THE REGION LATE
THIS AFTERNOON INTO THE EARLY EVENING HOURS. WHILE MOST THE ACTIVITY
HAS MOVED EAST...SHOWERS CAN STILL DEVELOP. CANNOT RULE OUT A
THUNDERSTORM OR TWO BUT ABUNDANT MOISTURE IS EXPECTED TO LIMIT
STRONG CONVECTIVE ACTIVITY FROM DEVELOPING. EXPECT RAINFALL AMOUNTS
TO REMAIN ONE QUARTER INCH OR LESS IN THE WESTERN MIDLANDS AND TAPER
TO LESS THAN A TENTH OF AN INCH OVER THE EASTERN MIDLANDS THROUGH
THIS AFTERNOON...MAINLY DUE TO A LACK OF FORCING.
TONIGHT...THE UPPER TROUGH WILL BE SLOW MOVING AS IT MOVES INTO
THE REGION AND WILL CONTINUE TO PROVIDE UPPER SUPPORT
OVERNIGHT...ESPECIALLY DURING THE EVENING HOURS...THEREFORE WILL
CONTINUE WITH LIKELY POPS OVERNIGHT. THE PRECIPITABLE WATER AXIS
SHIFTS OVER THE FORECAST AREA OVERNIGHT AND EXPECT THE BEST
RAINFALL ACCUMULATION TO OCCUR DURING THIS PERIOD. THE WESTERN AND
NORTHERN MIDLANDS WILL LIKELY SEE THE HIGHEST AMOUNTS...POSSIBLY
UP TO AN INCH...BUT THE ENTIRE FORECAST AREA SHOULD SEE MODERATE
MEASURABLE RAINFALL THROUGH EARLY MONDAY MORNING. TEMPERATURES
TONIGHT WILL BE LIMITED BY INCREASED DEWPOINTS AND CLOUDS AND
PRECIPITATION...GENERALLY IN THE MID 60S.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
SURFACE TROUGH WILL REMAIN ACROSS THE AREA THROUGH THE PERIOD AND
SHOULD PROVIDE FOCUS FOR SCATTERED SHOWERS AND THUNDERSTORMS.
AIR MASS APPEARS TO REMAIN MODERATELY MOIST AND INCREASINGLY UNSTABLE THROUGH
THE PERIOD. SOME DRYING SUGGESTED BY MODELS ESPECIALLY GFS...HOWEVER
EXPECT PRECIPITABLE WATER TO REMAIN RELATIVELY HIGH...NEAR 1.5
INCHES AT TIMES WITH PERSISTENT SOUTHWEST MOIST 850MB FLOW AHEAD
OF UPPER LEVEL TROUGH ACROSS THE MISSISSIPPI VALLEY AND MIDWEST.
SEVERAL SHORT WAVE TRIGGERS LIKELY TO ROTATE THROUGH THE
REGION...WHICH SHOULD AID THUNDERSTORM DEVELOPMENT...HOWEVER
TIMING OF WAVES DIFFICULT. FORECAST HIGH CHANCE POPS DURING THE
LATE AFTERNOON AND EVENING TUESDAY...POSSIBLY LATE INTO TUESDAY
NIGHT ASSOCIATED WITH POSSIBLE STRONGER SHORT WAVE. CHANCE
WEDNESDAY ESPECIALLY EAST MIDLANDS WHERE DEEPER MOISTURE IS
AND STRONGER UPPER LEVEL FORCING IS LOCATED. TEMPERATURES SHOULD BE
WARMER TUESDAY AND WEDNESDAY WITH SOME BREAKS IN THE OVERCAST MID
MORNING THROUGH EARLY AFTERNOON.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
MEDIUM RANGE MODELS HAVE COME INTO REASONABLE AGREEMENT WITH
POTENTIAL COASTAL LOW OFF THE CAROLINA COAST DURING THE EXTENDED
FORECAST PERIODS. BOTH GFS/ECMWF PUSH THE TROUGH FAR ENOUGH OFF
THE COAST THAT CONFIDENCE HAS INCREASED THAT THE SYSTEM LIKELY
WILL NOT AFFECT THE FORECAST AREA VERY MUCH. HIGH PRESSURE BUILDS
DOWN THE EAST COAST THURSDAY AND FRIDAY AS AN UPPER RIDGE BUILDS
OVER THE LOWER MISSISSIPPI VALLEY NORTHWARD INTO THE OHIO VALLEY
FOR THE WEEKEND. THIS WILL YIELD DRY WEATHER OVER OUR AREA THROUGH
THE WEEKEND WITH NEAR NORMAL TEMPERATURES EXPECTED.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
UPPER TROUGH STILL TO THE WEST OF THE FORECAST AREA BRINGING
PLENTY OF MOISTURE ON LOW LEVEL SOUTH TO SOUTHWEST WIND FLOW.
AIR MASS NEARLY SATURATED WITH BOTH LAPS AND MODEL SOUNDING MOIST
ADIABATIC. THIS SHOULD LIMIT THUNDERSTORM DEVELOPMENT BUT SHOWERS
ARE EXPECTED TO DEVELOP ANY TIME THIS AFTERNOON THROUGH THE EARLY
EVENING HOURS WITH JUST A MODEST TRIGGER. RUC13 H5 SHOWS WEAK
TROUGHINESS DURING THIS PERIOD...SO DECIDED TO MENTION SHOWERS IN
THE VICINITY FOR THE MOST PART. WILL GO MAINLY VFR BUT BRIEF IFR
TO MVFR CONDITIONS ARE POSSIBLE IN JUST ABOUT ANY SHOWER.
THUNDERSTORMS ARE ALSO POSSIBLE BUT NOT CONFIDENT ENOUGH TO PUT
IN THE TAF SITES. CAE 88D SHOWS STRONGEST CONVECTIVE ACTIVITY WITH
LIGHTNING WELL EAST OF TAF SITES WITH CONVECTIVE LINE WHICH MOVED
THROUGH EARLIER THIS MORNING. ALSO...AIRMASS APPEARS MORE UNSTABLE
TO THE EAST WITH LAPS CAPES OVER 3000 J/KG AND LAPS LIS -6/-7. MORE
MODEST DYNAMICS OVER TAF SITES WITH LAPS CAPES AROUND 2000 J/KG AND
LAPS LIS AROUND -5. TREND GOOD THROUGH ABOUT MIDNIGHT TONIGHT...04Z.
SHOWERS ARE EXPECTED TO TAPER OFF BEFORE THEN THOUGH AROUND 01-02Z.
AFTER MIDNIGHT...MOIST SOUTHWEST WIND FLOW WILL CONTINUE IN THE
LOWER LEVELS AND IT SHOULD FAVOR MORE IFR STRATUS CEILING THAN IFR
FOG. WILL GO MAINLY MVFR VSBYS WITH FOG MOST LOCATIONS TUESDAY NEAR
DAYBREAK BUT WILL HAVE LOWER IFR VSBYS AT AGS AND OGB. AFTER 14Z
TUESDAY MORNING...CONDITIONS SHOULD HAVE IMPROVED TO VFR AGAIN BUT
WILL KEEP SHOWER IN THE VICINITY REMARKS AS MOISTURE AND UPPER
FEATURES STILL SIMILAR TO THOSE TODAY.
EXTENDED AVIATION OUTLOOK...WIDESPREAD MVFR TO IFR CONDITIONS
POSSIBLE AGAIN WEDNESDAY MORNING AS LOW PRESSURE SYSTEM SLOWLY MOVES
EAST.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1029 PM CDT TUE MAY 15 2012
.DISCUSSION...
823 PM CDT
AS THE FRONTAL BOUNDARY CONTINUED TO SAG SOUTHEAST ACROSS
SOUTHCENTRAL WISC STRETCHING WEST THROUGH CENTRAL IA...ISOLATED
SHOWERS AND THUNDERSTORMS HAD DEVELOPED. THIS WAS FOCUSED ALONG AN
ENHANCED MID-LVL MOISTURE CONVERGENCE TONGUE...AND CONTINUED TO
PRESS SOUTHEAST TOWARDS NORTHERN IL. THE ENVIRONMENT OVER NORTHERN
IL LATE THIS AFTERNOON/EARLY EVENING...HAD INDICATED STEEP MID-LVL
LAPSE RATES DESPITE A CONTINUED RELATIVELY DRY SOUNDING. WHILE THE
MOISTURE WAS LACKING...FORCING WAS AIDING IN MAINTAING THE
ISOLATED CONVECTION AND THE MAIN CONCERN CONTINUED TO BE STRONG TO
SEVERE WIND GUSTS. WSR-88D RADAR INDICATED EARLY THIS EVENING
VELOCITY RETURNS NEAR 40 TO AT TIMES 50 KTS. HOWEVER...THE PAST
20-30 MINUTES HAVE INDICATED A STEADY DOWNWARD TREND IN THE
REFLECTIVITY AND VELOCITY PATTERN...HOWEVER MID-LVL LAPSE RATES
HAVE REMAINED RELATIVELY STEEP.
AS WE CONTINUE TO LOSE SFC HEATING AND MOVE TOWARDS THE NOCTURNAL
HOURS...SFC INSTABILITY AND MOISTURE CONVERGENCE WILL DIMINISH.
THIS SHOULD PROVIDE A STEADY DIMINISHING TREND IN THE
PRECIPITATION AND CONVECTION THROUGHOUT THE REMAINDER OF THE
EVENING. OCCASIONAL WIND GUSTS AHEAD OF THE FRONTAL BOUNDARY COULD
STILL APPROACH 50 MPH...HOWEVER ANTICIPATE THAT THIS WILL BE LESS
FREQUENT. WINDS WILL THEN VEER TO NORTHWEST AND EVENTUALLY
NORTHERLY ON THE BACK SIDE OF THE FRONT. IN ADDITION DRY AIR WILL
RAPIDLY PUSH IN BEHIND THIS BOUNDARY...ALLOWING DEW POINTS TO FALL
MAINLY INTO THE UPR 30S TO LOWER 40S. ONCE THE CLOUDS AND PRECIP
PUSHES SOUTH/SOUTHEAST...TEMPS WILL STEADILY RADIATE INTO THE MID
40S. CLOSER TO DOWNTOWN CHICAGO AND THE URBAN HEAT ISLAND...TEMPS
SHOULD BOTTOM OUT ARND 50 DEG.
BEACHLER
//PREV DISCUSSION...
251 PM CDT
FORECAST FOCUS IN NEAR TERM REMAINS COLD FRONTAL PASSAGE THIS
EVENING AND THE POTENTIAL FOR ISOLATED/SCATTERED CONVECTION. AFTER A
MUCH COOLER DAY WEDNESDAY...A WARMING TREND BACK TO SUMMER-LIKE
TEMPERATURES AND EVENTUALLY AND INCREASING POTENTIAL FOR
THUNDERSTORMS IS EXPECTED THROUGH THE WEEKEND.
AT 19Z...SFC ANALYSIS DEPICTS COLD FRONT STRETCHING FROM NEAR GREEN
BAY WISCONSIN...TO AMES IN CENTRAL IOWA. WARM SECTOR AHEAD OF FRONT
IS CHARACTERIZED BY TEMPS IN MID-UPPER 80S FROM NORTHERN IL BACK
INTO EASTERN IA...THOUGH VERY DRY LOW LEVELS AS INDICATED BY SFC DEW
PTS GENERALLY IN THE UPPER 30S TO MID 40S. THIS NOT SURPRISING GIVEN
EXTREMELY DRY LOW-MID LEVELS SEEN IN 12Z RAOBS AT UPSTREAM AT
MPX/OAX...THOUGH THERE IS A NARROW AXIS OF SLIGHTLY HIGHER DWPTS
FROM WESTERN IL INTO NORTHEAST IL. 18Z RAP APPEARS TO HAVE A DECENT
HANDLE ON THE LOW LEVEL MOISTURE FIELD...AND REMAINS CONSISTENT IN
DEVELOPING CONVECTIVE PRECIP AHEAD OF FRONT ACROSS CNTRL/EASTERN WI
AND DEVELOPING IT SOUTHEAST INTO NORTHERN/NORTHEAST IL EARLY THIS
EVENING. DESPITE VIGOROUS MID-LEVEL SHORT WAVE DIGGING SOUTHEAST
ACROSS THE NORTHERN LAKES...STEEP LOW/MID LEVEL LAPSE RATES AND THE
APPROACH OF A RELATIVELY STRONG COLD FRONTAL BOUNDARY...DEARTH OF
LOW LEVEL MOISTURE SUGGESTS IT WILL LIKELY BE DIFFICULT TO DEVELOP
SIGNIFICANT THUNDERSTORM COVERAGE...WITH HIGH LCL/LFC AND FAIRLY
SKINNY CAPE PROFILES OF 200-300 J/KG ALOFT PER RAP SOUNDINGS. THUS
WHILE ISOLATED-SCATTERED STORMS CANT BE RULED OUT COMPLETELY WITH
FROPA EARLY THIS EVENING...CONTINUE TO SUSPECT COVERAGE WILL BE
RELATIVELY LOW AND CONDITIONAL SEVERE THREAT MINIMAL. AS NOTED
PREVIOUSLY...ANY ACTIVITY WHICH DOES DEVELOP SHOULD HAVE A FAIRLY
STRONG DIURNAL COMPONENT AND SHOULD FADE QUICKLY WITH COOLING OF
BOUNDARY LAYER BEYOND SUNSET. WILL CONTINUE TO MAINTAIN ONLY LOW
CHANCE POPS.
HIGH PRESSURE WILL THEN BUILD ACROSS THE GREAT LAKES REGION
WEDNESDAY IN THE WAKE OF THE MID-LEVEL WAVE AND COLD FRONT. MUCH
COOLER TEMPS THAN TODAY CAN BE EXPECTED...RANGING FROM AROUND 60
NEAR THE LAKE MICHIGAN SHORE TO THE LOW 70S IN THE FAR WEST/SOUTH
REACHES OF THE CWA. FLAT UPPER LEVEL RIDGE THEN SPREADS ACROSS THE
MIDWEST THURSDAY...WITH LOW LEVEL WARM ADVECTION FOCUSING ACROSS THE
UPPER MISSISSIPPI VALLEY AND ACROSS THE NORTHERN LAKES FRIDAY. AXIS
OF LOW LEVEL 40-50 KT JET KEEPS THUNDERSTORM FOCUS NORTH/NORTHWEST
OF THE CWA THROUGH THIS TIME. UPPER RIDGE STRENGTHENS OVER THE
MIDWEST INTO THE WEEKEND AS BROAD TROUGH PUSHES EAST ACROSS THE
WESTERN HALF OF THE CONUS. SOUTHEAST/SOUTH FLOW THROUGH THE PERIOD
WILL LEAD TO TEMPS GRADUALLY WARMING FROM THE 70S THURSDAY INTO THE
LOW-MID80S FRI AND MID 80S SAT. LOW LEVEL MOISTURE WILL ALSO
GRADUALLY INCREASE FROM THE WEST/SOUTHWEST OVER THE WEEKEND AS
WESTERN TROUGH AND COLD FRONT SLOWLY APPROACH. GUIDANCE HAS SLOWED
FRONTAL ARRIVAL SOMEWHAT...HOLDING OFF GREATER PRECIP/THUNDERSTORM
THREAT UNTIL SUNDAY NIGHT AND MONDAY. UPPER TROUGH THEN MOVES SLOWLY
ACROSS THE AREA EARLY NEXT WEEK WITH COOLER WEATHER AS LOW LEVEL
FLOW BECOMES NORTHERLY BEHIND THE FRONT.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* FRONTAL PASSAGE THIS EVENING
* NORTHERLY WINDS BECOMING NORTHEASTERLY
SHEA
//DISCUSSION...UPDATED 00Z...
MAIN CONCERNS THIS EVENING ARE SHOWERS AND THE OCCASIONAL CLAP OF
THUNDER THAT ARE MOVING ACROSS THE TERMINALS...OR WILL BE MOVING
OVERHEAD OVER THE NEXT HOUR OR SO. MAIN STORMS HAVE ALREADY TAPPED
INTO THE MOST UNSTABLE PARTS OF THE ATMOSPHERE AND ARE HAVING
DIFFICULTY PRODUCING ANYTHING BEYOND STRONG WIND GUSTS. AS THEY
MOVE THROUGH THEY ARE RAINING WITH VFR VISIBILITIES AND CIGS ARE
ALSO REMAINING VFR. WITH THE DRY ATMOSPHERE...STRONG WIND GUSTS
HAVE BEEN NOTED. ADDED IN A TEMPO GROUP TO ACCOMODATE...AND
VARIOUS UPSTREAM SITES HAVE SHOWN WINDS SUSTAINED OUT OF THE
NORTHWEST AROUND 20 KT...WITH GUSTS IN THE MID 30 KT RANGE. MAIN
FRONT WILL THEN SETTLE SOUTH AND WINDS WILL RAPIDLY SHIFT THROUGH
NORTHWESTERLY TO NORTH-NORTHEASTERLY OVERNIGHT. WITH HIGH PRESSURE
BUILDING IN BEHIND THE FRONT...WINDS ARE EXPECTED TO REMAIN
RELATIVELY LIGHT THROUGH TOMORROW.
SHEA
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* MODERATE TO HIGH CONFIDENCE WITH WINDS AND SHIFT THIS EVENING
* HIGH CONFIDENCE ON TIMING OF SHRA/ OCNL TSRA
* HIGH CONFIDENCE IN POST SHOWER FORECAST ELEMENTS
SHEA
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
* THURSDAY THROUGH SATURDAY...VFR.
* SUNDAY...CHANCE OF TSRA. GUSTY SOUTHWEST WINDS.
* MONDAY...CHANCE OF TSRA.
SHEA
&&
.MARINE...
353 PM CDT
A COLD FRONT TRAILING BACK SOUTHWESTWARD FROM LOW PRESSURE OVER
FAR EASTERN ONTARIO BETWEEN JAMES BAY AND GEORGIAN BAY...ACROSS
THE FAR EASTERN UPPER PENINSULA OF MI...CENTRAL WI AND SE IA WILL
CONTINUE TO PUSH SE ACROSS THE UPPER GREAT LAKES AND MID MS VALLEY
THIS EVENING AS THE LOW CONTINUES TO MOVE E TO CENTRAL QUEBEC
DURING THE NIGHT. HIGH PRESSURE CENTERED OVER SOUTHERN MANITOBA
AND EXTENDING S ACROSS THE NORTHERN PLAINS WILL BUILD ACROSS THE
UPPER MIDWEST AND MID MO VALLEY OVERNIGHT BEHIND THE COLD FRONT.
COLD AIR ADVECTION AND A SIGNIFICANT 3 HR PRESSURE RISE CENTER OF
5-6 MB WAS MOVING SE ACROSS CENTRAL LAKE SUPERIOR AND THE U.P. OF
MI GENERATING SOME NW GUSTS TO AROUND 30 KT BEHIND THE COLD FRONT.
THIS PRESSURE RISE CENTER IS EXPECTED TO SWING ACROSS NORTHERN
LAKE MI THIS EVE CAUSING SOME GUSTY NW AND N WINDS MAINLY ON THE N
PORTION OF THE LAKE.
HIGH PRESSURE CENTERED OVER SOUTHERN MANITOBA AND EXTENDING S
ACROSS THE NORTHERN PLAINS WILL BUILD ACROSS THE UPPER MIDWEST AND
MID MO VALLEY OVERNIGHT BEHIND THE COLD FRONT WITH THE PRESSURE
GRADIENT OVER LAKE MI GRADUALLY WEAKENING AND THE RESULTANT WINDS
SLACKING. THIS HIGH THEN MOVES E OVER THE UPPER GREAT LAKES DURING
WED BRINGING LIGHTER WINDS TO THE LAKE. AS THE HIGH SHIFTS FURTHER
E TO THE LOWER GREAT LAKES DURING THU SE WINDS WILL START TO
SLOWLY INCREASE THU NIGHT AND FRI AS LOW PRESSURE MOVES E OVER THE
CENTRAL PLAINS.
TRS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
837 PM CDT TUE MAY 15 2012
.DISCUSSION...
823 PM CDT
AS THE FRONTAL BOUNDARY CONTINUED TO SAG SOUTHEAST ACROSS
SOUTHCENTRAL WISC STRETCHING WEST THROUGH CENTRAL IA...ISOLATED
SHOWERS AND THUNDERSTORMS HAD DEVELOPED. THIS WAS FOCUSED ALONG AN
ENHANCED MID-LVL MOISTURE CONVERGENCE TONGUE...AND CONTINUED TO
PRESS SOUTHEAST TOWARDS NORTHERN IL. THE ENVIRONMENT OVER NORTHERN
IL LATE THIS AFTERNOON/EARLY EVENING...HAD INDICATED STEEP MID-LVL
LAPSE RATES DESPITE A CONTINUED RELATIVELY DRY SOUNDING. WHILE THE
MOISTURE WAS LACKING...FORCING WAS AIDING IN MAINTAING THE
ISOLATED CONVECTION AND THE MAIN CONCERN CONTINUED TO BE STRONG TO
SEVERE WIND GUSTS. WSR-88D RADAR INDICATED EARLY THIS EVENING
VELOCITY RETURNS NEAR 40 TO AT TIMES 50 KTS. HOWEVER...THE PAST
20-30 MINUTES HAVE INDICATED A STEADY DOWNWARD TREND IN THE
REFLECTIVITY AND VELOCITY PATTERN...HOWEVER MID-LVL LAPSE RATES
HAVE REMAINED RELATIVELY STEEP.
AS WE CONTINUE TO LOSE SFC HEATING AND MOVE TOWARDS THE NOCTURNAL
HOURS...SFC INSTABILITY AND MOISTURE CONVERGENCE WILL DIMINISH.
THIS SHOULD PROVIDE A STEADY DIMINISHING TREND IN THE
PRECIPITATION AND CONVECTION THROUGHOUT THE REMAINDER OF THE
EVENING. OCCASIONAL WIND GUSTS AHEAD OF THE FRONTAL BOUNDARY COULD
STILL APPROACH 50 MPH...HOWEVER ANTICIPATE THAT THIS WILL BE LESS
FREQUENT. WINDS WILL THEN VEER TO NORTHWEST AND EVENTUALLY
NORTHERLY ON THE BACK SIDE OF THE FRONT. IN ADDITION DRY AIR WILL
RAPIDLY PUSH IN BEHIND THIS BOUNDARY...ALLOWING DEW POINTS TO FALL
MAINLY INTO THE UPR 30S TO LOWER 40S. ONCE THE CLOUDS AND PRECIP
PUSHES SOUTH/SOUTHEAST...TEMPS WILL STEADILY RADIATE INTO THE MID
40S. CLOSER TO DOWNTOWN CHICAGO AND THE URBAN HEAT ISLAND...TEMPS
SHOULD BOTTOM OUT ARND 50 DEG.
BEACHLER
&&
.PREV DISCUSSION...
251 PM CDT
FORECAST FOCUS IN NEAR TERM REMAINS COLD FRONTAL PASSAGE THIS
EVENING AND THE POTENTIAL FOR ISOLATED/SCATTERED CONVECTION. AFTER A
MUCH COOLER DAY WEDNESDAY...A WARMING TREND BACK TO SUMMER-LIKE
TEMPERATURES AND EVENTUALLY AND INCREASING POTENTIAL FOR
THUNDERSTORMS IS EXPECTED THROUGH THE WEEKEND.
AT 19Z...SFC ANALYSIS DEPICTS COLD FRONT STRETCHING FROM NEAR GREEN
BAY WISCONSIN...TO AMES IN CENTRAL IOWA. WARM SECTOR AHEAD OF FRONT
IS CHARACTERIZED BY TEMPS IN MID-UPPER 80S FROM NORTHERN IL BACK
INTO EASTERN IA...THOUGH VERY DRY LOW LEVELS AS INDICATED BY SFC DEW
PTS GENERALLY IN THE UPPER 30S TO MID 40S. THIS NOT SURPRISING GIVEN
EXTREMELY DRY LOW-MID LEVELS SEEN IN 12Z RAOBS AT UPSTREAM AT
MPX/OAX...THOUGH THERE IS A NARROW AXIS OF SLIGHTLY HIGHER DWPTS
FROM WESTERN IL INTO NORTHEAST IL. 18Z RAP APPEARS TO HAVE A DECENT
HANDLE ON THE LOW LEVEL MOISTURE FIELD...AND REMAINS CONSISTENT IN
DEVELOPING CONVECTIVE PRECIP AHEAD OF FRONT ACROSS CNTRL/EASTERN WI
AND DEVELOPING IT SOUTHEAST INTO NORTHERN/NORTHEAST IL EARLY THIS
EVENING. DESPITE VIGOROUS MID-LEVEL SHORT WAVE DIGGING SOUTHEAST
ACROSS THE NORTHERN LAKES...STEEP LOW/MID LEVEL LAPSE RATES AND THE
APPROACH OF A RELATIVELY STRONG COLD FRONTAL BOUNDARY...DEARTH OF
LOW LEVEL MOISTURE SUGGESTS IT WILL LIKELY BE DIFFICULT TO DEVELOP
SIGNIFICANT THUNDERSTORM COVERAGE...WITH HIGH LCL/LFC AND FAIRLY
SKINNY CAPE PROFILES OF 200-300 J/KG ALOFT PER RAP SOUNDINGS. THUS
WHILE ISOLATED-SCATTERED STORMS CANT BE RULED OUT COMPLETELY WITH
FROPA EARLY THIS EVENING...CONTINUE TO SUSPECT COVERAGE WILL BE
RELATIVELY LOW AND CONDITIONAL SEVERE THREAT MINIMAL. AS NOTED
PREVIOUSLY...ANY ACTIVITY WHICH DOES DEVELOP SHOULD HAVE A FAIRLY
STRONG DIURNAL COMPONENT AND SHOULD FADE QUICKLY WITH COOLING OF
BOUNDARY LAYER BEYOND SUNSET. WILL CONTINUE TO MAINTAIN ONLY LOW
CHANCE POPS.
HIGH PRESSURE WILL THEN BUILD ACROSS THE GREAT LAKES REGION
WEDNESDAY IN THE WAKE OF THE MID-LEVEL WAVE AND COLD FRONT. MUCH
COOLER TEMPS THAN TODAY CAN BE EXPECTED...RANGING FROM AROUND 60
NEAR THE LAKE MICHIGAN SHORE TO THE LOW 70S IN THE FAR WEST/SOUTH
REACHES OF THE CWA. FLAT UPPER LEVEL RIDGE THEN SPREADS ACROSS THE
MIDWEST THURSDAY...WITH LOW LEVEL WARM ADVECTION FOCUSING ACROSS THE
UPPER MISSISSIPPI VALLEY AND ACROSS THE NORTHERN LAKES FRIDAY. AXIS
OF LOW LEVEL 40-50 KT JET KEEPS THUNDERSTORM FOCUS NORTH/NORTHWEST
OF THE CWA THROUGH THIS TIME. UPPER RIDGE STRENGTHENS OVER THE
MIDWEST INTO THE WEEKEND AS BROAD TROUGH PUSHES EAST ACROSS THE
WESTERN HALF OF THE CONUS. SOUTHEAST/SOUTH FLOW THROUGH THE PERIOD
WILL LEAD TO TEMPS GRADUALLY WARMING FROM THE 70S THURSDAY INTO THE
LOW-MID80S FRI AND MID 80S SAT. LOW LEVEL MOISTURE WILL ALSO
GRADUALLY INCREASE FROM THE WEST/SOUTHWEST OVER THE WEEKEND AS
WESTERN TROUGH AND COLD FRONT SLOWLY APPROACH. GUIDANCE HAS SLOWED
FRONTAL ARRIVAL SOMEWHAT...HOLDING OFF GREATER PRECIP/THUNDERSTORM
THREAT UNTIL SUNDAY NIGHT AND MONDAY. UPPER TROUGH THEN MOVES SLOWLY
ACROSS THE AREA EARLY NEXT WEEK WITH COOLER WEATHER AS LOW LEVEL
FLOW BECOMES NORTHERLY BEHIND THE FRONT.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* GUSTY WINDS AND FRONTAL PASSAGE
* ASSOCIATED WIND GUSTS
* SHOWERS AND THE OCNL CLAP OF THUNDER THIS EVENING
SHEA
//DISCUSSION...UPDATED 00Z...
MAIN CONCERNS THIS EVENING ARE SHOWERS AND THE OCCASIONAL CLAP OF
THUNDER THAT ARE MOVING ACROSS THE TERMINALS...OR WILL BE MOVING
OVERHEAD OVER THE NEXT HOUR OR SO. MAIN STORMS HAVE ALREADY TAPPED
INTO THE MOST UNSTABLE PARTS OF THE ATMOSPHERE AND ARE HAVING
DIFFICULTY PRODUCING ANYTHING BEYOND STRONG WIND GUSTS. AS THEY
MOVE THROUGH THEY ARE RAINING WITH VFR VISIBILITIES AND CIGS ARE
ALSO REMAINING VFR. WITH THE DRY ATMOSPHERE...STRONG WIND GUSTS
HAVE BEEN NOTED. ADDED IN A TEMPO GROUP TO ACCOMODATE...AND
VARIOUS UPSTREAM SITES HAVE SHOWN WINDS SUSTAINED OUT OF THE
NORTHWEST AROUND 20 KT...WITH GUSTS IN THE MID 30 KT RANGE. MAIN
FRONT WILL THEN SETTLE SOUTH AND WINDS WILL RAPIDLY SHIFT THROUGH
NORTHWESTERLY TO NORTH-NORTHEASTERLY OVERNIGHT. WITH HIGH PRESSURE
BUILDING IN BEHIND THE FRONT...WINDS ARE EXPECTED TO REMAIN
RELATIVELY LIGHT THROUGH TOMORROW.
SHEA
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* MODERATE TO HIGH CONFIDENCE WITH WINDS AND SHIFT THIS EVENING
* HIGH CONFIDENCE ON TIMING OF SHRA/ OCNL TSRA
* HIGH CONFIDENCE IN POST SHOWER FORECAST ELEMENTS
SHEA
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
* THURSDAY THROUGH SATURDAY...VFR.
* SUNDAY...CHANCE OF TSRA. GUSTY SOUTHWEST WINDS.
* MONDAY...CHANCE OF TSRA.
SHEA
&&
.MARINE...
353 PM CDT
A COLD FRONT TRAILING BACK SOUTHWESTWARD FROM LOW PRESSURE OVER
FAR EASTERN ONTARIO BETWEEN JAMES BAY AND GEORGIAN BAY...ACROSS
THE FAR EASTERN UPPER PENINSULA OF MI...CENTRAL WI AND SE IA WILL
CONTINUE TO PUSH SE ACROSS THE UPPER GREAT LAKES AND MID MS VALLEY
THIS EVENING AS THE LOW CONTINUES TO MOVE E TO CENTRAL QUEBEC
DURING THE NIGHT. HIGH PRESSURE CENTERED OVER SOUTHERN MANITOBA
AND EXTENDING S ACROSS THE NORTHERN PLAINS WILL BUILD ACROSS THE
UPPER MIDWEST AND MID MO VALLEY OVERNIGHT BEHIND THE COLD FRONT.
COLD AIR ADVECTION AND A SIGNIFICANT 3 HR PRESSURE RISE CENTER OF
5-6 MB WAS MOVING SE ACROSS CENTRAL LAKE SUPERIOR AND THE U.P. OF
MI GENERATING SOME NW GUSTS TO AROUND 30 KT BEHIND THE COLD FRONT.
THIS PRESSURE RISE CENTER IS EXPECTED TO SWING ACROSS NORTHERN
LAKE MI THIS EVE CAUSING SOME GUSTY NW AND N WINDS MAINLY ON THE N
PORTION OF THE LAKE.
HIGH PRESSURE CENTERED OVER SOUTHERN MANITOBA AND EXTENDING S
ACROSS THE NORTHERN PLAINS WILL BUILD ACROSS THE UPPER MIDWEST AND
MID MO VALLEY OVERNIGHT BEHIND THE COLD FRONT WITH THE PRESSURE
GRADIENT OVER LAKE MI GRADUALLY WEAKENING AND THE RESULTANT WINDS
SLACKING. THIS HIGH THEN MOVES E OVER THE UPPER GREAT LAKES DURING
WED BRINGING LIGHTER WINDS TO THE LAKE. AS THE HIGH SHIFTS FURTHER
E TO THE LOWER GREAT LAKES DURING THU SE WINDS WILL START TO
SLOWLY INCREASE THU NIGHT AND FRI AS LOW PRESSURE MOVES E OVER THE
CENTRAL PLAINS.
TRS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
712 PM CDT TUE MAY 15 2012
.DISCUSSION...
251 PM CDT
FORECAST FOCUS IN NEAR TERM REMAINS COLD FRONTAL PASSAGE THIS
EVENING AND THE POTENTIAL FOR ISOLATED/SCATTERED CONVECTION. AFTER A
MUCH COOLER DAY WEDNESDAY...A WARMING TREND BACK TO SUMMER-LIKE
TEMPERATURES AND EVENTUALLY AND INCREASING POTENTIAL FOR
THUNDERSTORMS IS EXPECTED THROUGH THE WEEKEND.
AT 19Z...SFC ANALYSIS DEPICTS COLD FRONT STRETCHING FROM NEAR GREEN
BAY WISCONSIN...TO AMES IN CENTRAL IOWA. WARM SECTOR AHEAD OF FRONT
IS CHARACTERIZED BY TEMPS IN MID-UPPER 80S FROM NORTHERN IL BACK
INTO EASTERN IA...THOUGH VERY DRY LOW LEVELS AS INDICATED BY SFC DEW
PTS GENERALLY IN THE UPPER 30S TO MID 40S. THIS NOT SURPRISING GIVEN
EXTREMELY DRY LOW-MID LEVELS SEEN IN 12Z RAOBS AT UPSTREAM AT
MPX/OAX...THOUGH THERE IS A NARROW AXIS OF SLIGHTLY HIGHER DWPTS
FROM WESTERN IL INTO NORTHEAST IL. 18Z RAP APPEARS TO HAVE A DECENT
HANDLE ON THE LOW LEVEL MOISTURE FIELD...AND REMAINS CONSISTENT IN
DEVELOPING CONVECTIVE PRECIP AHEAD OF FRONT ACROSS CNTRL/EASTERN WI
AND DEVELOPING IT SOUTHEAST INTO NORTHERN/NORTHEAST IL EARLY THIS
EVENING. DESPITE VIGOROUS MID-LEVEL SHORT WAVE DIGGING SOUTHEAST
ACROSS THE NORTHERN LAKES...STEEP LOW/MID LEVEL LAPSE RATES AND THE
APPROACH OF A RELATIVELY STRONG COLD FRONTAL BOUNDARY...DEARTH OF
LOW LEVEL MOISTURE SUGGESTS IT WILL LIKELY BE DIFFICULT TO DEVELOP
SIGNIFICANT THUNDERSTORM COVERAGE...WITH HIGH LCL/LFC AND FAIRLY
SKINNY CAPE PROFILES OF 200-300 J/KG ALOFT PER RAP SOUNDINGS. THUS
WHILE ISOLATED-SCATTERED STORMS CANT BE RULED OUT COMPLETELY WITH
FROPA EARLY THIS EVENING...CONTINUE TO SUSPECT COVERAGE WILL BE
RELATIVELY LOW AND CONDITIONAL SEVERE THREAT MINIMAL. AS NOTED
PREVIOUSLY...ANY ACTIVITY WHICH DOES DEVELOP SHOULD HAVE A FAIRLY
STRONG DIURNAL COMPONENT AND SHOULD FADE QUICKLY WITH COOLING OF
BOUNDARY LAYER BEYOND SUNSET. WILL CONTINUE TO MAINTAIN ONLY LOW
CHANCE POPS.
HIGH PRESSURE WILL THEN BUILD ACROSS THE GREAT LAKES REGION
WEDNESDAY IN THE WAKE OF THE MID-LEVEL WAVE AND COLD FRONT. MUCH
COOLER TEMPS THAN TODAY CAN BE EXPECTED...RANGING FROM AROUND 60
NEAR THE LAKE MICHIGAN SHORE TO THE LOW 70S IN THE FAR WEST/SOUTH
REACHES OF THE CWA. FLAT UPPER LEVEL RIDGE THEN SPREADS ACROSS THE
MIDWEST THURSDAY...WITH LOW LEVEL WARM ADVECTION FOCUSING ACROSS THE
UPPER MISSISSIPPI VALLEY AND ACROSS THE NORTHERN LAKES FRIDAY. AXIS
OF LOW LEVEL 40-50 KT JET KEEPS THUNDERSTORM FOCUS NORTH/NORTHWEST
OF THE CWA THROUGH THIS TIME. UPPER RIDGE STRENGTHENS OVER THE
MIDWEST INTO THE WEEKEND AS BROAD TROUGH PUSHES EAST ACROSS THE
WESTERN HALF OF THE CONUS. SOUTHEAST/SOUTH FLOW THROUGH THE PERIOD
WILL LEAD TO TEMPS GRADUALLY WARMING FROM THE 70S THURSDAY INTO THE
LOW-MID80S FRI AND MID 80S SAT. LOW LEVEL MOISTURE WILL ALSO
GRADUALLY INCREASE FROM THE WEST/SOUTHWEST OVER THE WEEKEND AS
WESTERN TROUGH AND COLD FRONT SLOWLY APPROACH. GUIDANCE HAS SLOWED
FRONTAL ARRIVAL SOMEWHAT...HOLDING OFF GREATER PRECIP/THUNDERSTORM
THREAT UNTIL SUNDAY NIGHT AND MONDAY. UPPER TROUGH THEN MOVES SLOWLY
ACROSS THE AREA EARLY NEXT WEEK WITH COOLER WEATHER AS LOW LEVEL
FLOW BECOMES NORTHERLY BEHIND THE FRONT.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* GUSTY WINDS AND FRONTAL PASSAGE
* ASSOCIATED WIND GUSTS
* SHOWERS AND THE OCNL CLAP OF THUNDER THIS EVENING
SHEA
//DISCUSSION...UPDATED 00Z...
MAIN CONCERNS THIS EVENING ARE SHOWERS AND THE OCCASIONAL CLAP OF
THUNDER THAT ARE MOVING ACROSS THE TERMINALS...OR WILL BE MOVING
OVERHEAD OVER THE NEXT HOUR OR SO. MAIN STORMS HAVE ALREADY TAPPED
INTO THE MOST UNSTABLE PARTS OF THE ATMOSPHERE AND ARE HAVING
DIFFICULTY PRODUCING ANYTHING BEYOND STRONG WIND GUSTS. AS THEY
MOVE THROUGH THEY ARE RAINING WITH VFR VISIBILITIES AND CIGS ARE
ALSO REMAINING VFR. WITH THE DRY ATMOSPHERE...STRONG WIND GUSTS
HAVE BEEN NOTED. ADDED IN A TEMPO GROUP TO ACCOMODATE...AND
VARIOUS UPSTREAM SITES HAVE SHOWN WINDS SUSTAINED OUT OF THE
NORTHWEST AROUND 20 KT...WITH GUSTS IN THE MID 30 KT RANGE. MAIN
FRONT WILL THEN SETTLE SOUTH AND WINDS WILL RAPIDLY SHIFT THROUGH
NORTHWESTERLY TO NORTH-NORTHEASTERLY OVERNIGHT. WITH HIGH PRESSURE
BUILDING IN BEHIND THE FRONT...WINDS ARE EXPECTED TO REMAIN
RELATIVELY LIGHT THROUGH TOMORROW.
SHEA
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* MODERATE TO HIGH CONFIDENCE WITH WINDS AND SHIFT THIS EVENING
* HIGH CONFIDENCE ON TIMING OF SHRA/ OCNL TSRA
* HIGH CONFIDENCE IN POST SHOWER FORECAST ELEMENTS
SHEA
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
* THURSDAY THROUGH SATURDAY...VFR.
* SUNDAY...CHANCE OF TSRA. GUSTY SOUTHWEST WINDS.
* MONDAY...CHANCE OF TSRA.
SHEA
&&
.MARINE...
353 PM CDT
A COLD FRONT TRAILING BACK SOUTHWESTWARD FROM LOW PRESSURE OVER
FAR EASTERN ONTARIO BETWEEN JAMES BAY AND GEORGIAN BAY...ACROSS
THE FAR EASTERN UPPER PENINSULA OF MI...CENTRAL WI AND SE IA WILL
CONTINUE TO PUSH SE ACROSS THE UPPER GREAT LAKES AND MID MS VALLEY
THIS EVENING AS THE LOW CONTINUES TO MOVE E TO CENTRAL QUEBEC
DURING THE NIGHT. HIGH PRESSURE CENTERED OVER SOUTHERN MANITOBA
AND EXTENDING S ACROSS THE NORTHERN PLAINS WILL BUILD ACROSS THE
UPPER MIDWEST AND MID MO VALLEY OVERNIGHT BEHIND THE COLD FRONT.
COLD AIR ADVECTION AND A SIGNIFICANT 3 HR PRESSURE RISE CENTER OF
5-6 MB WAS MOVING SE ACROSS CENTRAL LAKE SUPERIOR AND THE U.P. OF
MI GENERATING SOME NW GUSTS TO AROUND 30 KT BEHIND THE COLD FRONT.
THIS PRESSURE RISE CENTER IS EXPECTED TO SWING ACROSS NORTHERN
LAKE MI THIS EVE CAUSING SOME GUSTY NW AND N WINDS MAINLY ON THE N
PORTION OF THE LAKE.
HIGH PRESSURE CENTERED OVER SOUTHERN MANITOBA AND EXTENDING S
ACROSS THE NORTHERN PLAINS WILL BUILD ACROSS THE UPPER MIDWEST AND
MID MO VALLEY OVERNIGHT BEHIND THE COLD FRONT WITH THE PRESSURE
GRADIENT OVER LAKE MI GRADUALLY WEAKENING AND THE RESULTANT WINDS
SLACKING. THIS HIGH THEN MOVES E OVER THE UPPER GREAT LAKES DURING
WED BRINGING LIGHTER WINDS TO THE LAKE. AS THE HIGH SHIFTS FURTHER
E TO THE LOWER GREAT LAKES DURING THU SE WINDS WILL START TO
SLOWLY INCREASE THU NIGHT AND FRI AS LOW PRESSURE MOVES E OVER THE
CENTRAL PLAINS.
TRS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
745 PM EDT TUE MAY 15 2012
.UPDATE/AVIATION... /00 UTC TAFS/
TIMING/LOSS OF INSOLATION/ TO RESULT IN SIGNIFICANT STABILIZATION IN
0-3KM LAPSE RATES TO LEE OF LAKE MICHIGAN WHICH SHOULD SPELL
ULTIMATE DEMISE OF LINEAR CONVECTION CNRTLY FM WCNTL MI TO KENOSHA
WI TO QUAD CITIES. MINOR ADJUSTMENT TO TAF TIMING OF INCRSD VFR
CLOUDS INTO KSBN AND ADDED VCSH TO ACCOUNT FOR POTNL SPOTTY
CONVECTION ON DECLINE...LEANING ON RAP/3KM HRRR FOR TIMING SUPPORT.
OTHERWISE DRY AIRMASS TO ASSURE VFR THROUGH ENTIRE FCST PD AND
BEYOND...AND QUITE PSBLY THROUGH THE WEEKEND. BLEND OF LAV/HRRR TO
CRNT FCST FOR SIG LWG POPS NWRN CWA IN NEAR TERM WITH SERN THIRD NOW
VOID OF ANY MENTION.
&&
.PREV DISCUSSION... /ISSUED 430 PM EDT TUE MAY 15 2012/
SHORT TERM.../TONIGHT-WED NGT/
CDFNT MOVG ACROSS WI/IA THIS AFTN WILL MOVE SE ACROSS OUR CWA
TONIGHT. BKN HIGH BASED CU AND ISOLATED LIGHTNING STRIKES ALONG
FRONT OVER WI/IA ATTM. SFC OBS AND 12Z UPR AIR ANALYSIS SUGGESTS
LATEST NCEP MODELS CONT TO BE TOO MOIST IN LOW LEVELS... THUS
CONFIDENCE IN BKN LINE OF SHOWERS/TSTMS DVLPG FROM MI-SE IA BY 00Z
AS DEPICTED BY LATEST 4KM SPC WRF IS LOW. HRRR INDICATING
CONSIDERABLY LOWER CHC OF CONVECTION REACHING OUR AREA AND APPEARS
TO BE HANDLING THE SFC DWPTS AHEAD OF THE FRONT A LITTLE BETTER. IN
EITHER CASE... ANY SHOWERS/TSTMS WHICH DEVELOP ALONG FRONT LATE
THIS AFTN/EARLY EVE SHOULD BE IN A WKNG/DISSIPATING STAGE UPON
REACHING OUR CWA GIVEN DRY AIRMASS IN PLACE AND DIURNAL
STABILIZATION. ALTHOUGH CONFIDENCE LOW IN CONVECTION REACHING OUR
AREA... FELT GOING LOW CHC OF TSTMS TONIGHT WORTH LEAVING IN FCST
ATTM. GIVEN STEEP LAPSE RATES ABOVE DVLPG SHALLOW NOCTURNAL SFC
BASED INVERSION... POTENTIAL FOR SOME GUSTY WINDS IF CONVECTION
DOES REACH OUR CWA.
HIGH PRESSURE BUILDING INTO THE AREA BEHIND THE FRONT WED WILL
RESULT IN CLEARING SKIES. FAIRLY STRONG CAA SHOULD HOLD TEMPS DOWN
ABOUT 10F FROM TODAYS READINGS DESPITE SUNNY SKIES MOST OF THE DAY.
WITH HIGH MOVG OVERHEAD WED NGT LIGHT WINDS AND DRY AIRMASS WILL
RESULT IN GOOD RADIATIONAL COOLING WITH LOWS IN THE L-M40S ACROSS
THE AREA.
LONG TERM...
PROGRESSIVE PATTN ALOFT CONTS TO HOLD SWAY THIS PD. LEAD SW TROUGH
OVR SRN ON THIS AFTN WILL RAPIDLY DRIVE EWD UP THROUGH THE ST LAW
VALLEY THU AS SFC RIDGING SHIFTS EWD W/ROBUST WAA DVLPG DURING THE
DAY. MEXMOS APPROXIMATION STILL HOLDS AND SEE NO REASON TO CHG
ANYTHING.
AFT THAT...SIG UPR RIDGING DVLPS EWD OF WRN US TROUGHING AND
INTENSIFIES ACRS THE MID ATL COAST THIS WEEKEND. THERMAL RIDGE
INBTWN WILL BE QUITE WARM FOR MID MAY STANDARDS WITH LOW-MID 80S
XPCD FRI-SUN. EJECTING WRN TROUGH SAT PROGGED TO QUICKLY DEAMPLIFY
EWD MON IN RESPONSE TO DOWNSTREAM UPR RIDGING AND RENEWED FOCUS ON A
MORE SIG WAVE TRAIN ENTERING NWPAC/SW CANADA. IN ADDN...CONTD
SUGGESTION OF A TROPICAL DISTURBANCE OVR THE WRN CARIBBEAN WILL
ELIMINATE ANY SIG GOMEX MSTR RTN. GIVEN CONTD POOR MODEL HANDLING OF
BNDRY LYR MSTR AND XPCD WKNG FNTL SYS...WILL SLASH GOING POPS LWR
MON/MON NIGHT. REMAINDER ON TRACK.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 4 PM EDT
WEDNESDAY FOR LMZ043-046.
&&
$$
SHORT TERM...JT
LONG TERM...T
AVIATION/UPDATE...MURPHY
AREA FORECAST DISCUSSION
NWS GOODLAND KS
553 PM MDT TUE MAY 15 2012
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 1249 PM MDT TUE MAY 15 2012
EARLY AFTERNOON WV IMAGERY AND RUC H5 ANALYSIS SHOW SHORTWAVE
RIDGE ACROSS CENTRAL ROCKIES...WITH DEEP UPPER LOW UPSTREAM OVER
NORTHERN CALIFORNIA. A COLD FRONT IS CURRENTLY JUST NORTH OF OUR
CWA...WITH TEMPERATURES AHEAD OF THE FRONT OVER OUR CWA IN THE MID
TO UPPER 80S...AND TEMPERATURES BEHIND THE FRONT IN THE MID TO
UPPER 70S.
THE COLD FRONT TO THE NORTH OF THE CWA WILL DROP SOUTH AND EAST
THIS EVENING...WITH INCREASING TD NORTH OF THE FRONT AS WINDS
SHIFT TO THE EAST-SOUTHEAST. IF TD VALUES IN THE LOW-MID 40S WERE
TO ADVECT INTO THE NORTHERN HALF OF OUR CWA...RADIATIONAL FOG
COULDN`T BE RULED OUT. GUIDANCE IS CURRENTLY SHOWING BL REMAINING
UNSATURATED THROUGH WED MORNING...SO FOG WAS LEFT OUT OF
FORECAST.
LARGE SCALE SUBSIDENCE AND A VERY DRY/STABLE AIR MASS WILL REMAIN
IN PLACE THROUGH WEDNESDAY AFTERNOON. SHORTWAVE TROUGH BEGINS TO
MOVE EAST INTO THE CENTRAL ROCKIES BY WED AFTERNOON...WHICH
COULD BRING THUNDERSTORM CHANCES TO EASTERN COLORADO COUNTIES BY
LATE WEDNESDAY AFTERNOON. OVERALL TREND IS TO SLOW DOWN THE
ARRIVAL OF LIFT/MOISTURE WITH THIS FEATURE...SO I LIMITED SLIGHT
CHANCE MENTION CLOSER TO 00Z OVER NW PART OF YUMA COUNTY.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 239 PM MDT TUE MAY 15 2012
THE NORTHERN PERIPHERY OF AN UPPER LEVEL RIDGE WILL MOVE OVER THE
AREA WEDNESDAY NIGHT. MEANWHILE A SHORT WAVE TROUGH WILL MOVE ALONG
THE PERIPHERY OF THE RIDGE...ENTERING THE NORTHWEST PART OF THE AREA
DURING THE EVENING. SLIGHT CHANCES FOR PRECIPITATION START DURING
THE EARLY EVENING AS POINT SOUNDINGS FROM 550 MB ON UP BEGIN TO
SATURATE OVER THE WESTERN PART OF YUMA COUNTY. WITH 100J/KG OF
700-500MB MOST UNSTABLE CAPE IN THE VICINITY AND CONVECTIVE
TEMPERATURES BEING REACHED DURING THE EARLY EVENING...AN ISOLATED
THUNDERSTORM IS CERTAINLY POSSIBLE AHEAD OF THE SHORT WAVE TROUGH.
WITH MOISTURE INCREASING ABOVE 600MB AND A LOBE OF 500MB VORTICITY
MOVING OVER THE NORTHWEST PART OF THE AREA AROUND MIDNIGHT...HAVE
PRECIPITATION CHANCES PEAKING AT THIS TIME THEN DECLINING TOWARDS
MORNING AS THE 500MB VORTICITY AND SHORT WAVE TROUGH MOVE NORTHEAST
INTO NEBRASKA. WITH A DEEP DRY LAYER IN PLACE...AM NOT TOO
CONFIDENT THAT ANY RAINFALL PRODUCED WILL MAKE IT TO THE
GROUND...BUT CANNOT COMPLETELY RULE OUT MEASURABLE PRECIPITATION
FROM OCCURRING.
THURSDAY ANOTHER SHORT WAVE TROUGH WILL MOVE INTO THE AREA DURING
THE LATE MORNING HOURS...MOVING ACROSS THE AREA THROUGH THE DAY AND
EXITING THE AREA DURING THE LATE EVENING. LATEST NAM HAS SHIFTED THE
TRACK OF THE TROUGH FURTHER SOUTH WHICH IS IN LINE WITH THE GFS. AS
SUCH HAVE SHIFTED THE BULK OF THE PRECIPITATION CHANCES TO AREAS
GENERALLY ALONG AND SOUTH OF HIGHWAY 24 DURING THE AFTERNOON. AS
THE TROUGH MOVES THROUGH...THE AREA OF 500MB VORTICITY BECOMES MORE
DISJOINTED. IN ADDITION THE DEEP DRY LAYER WILL PERSIST THROUGH THE
AFTERNOON AND EVENING...SO DECIDED TO KEEP PRECIPITATION CHANCES IN
THE SLIGHT CATEGORY. PRECIPITATION CHANCES SHIFT TO THE EASTERN
PART OF THE AREA DURING THE MID TO LATE AFTERNOON AS 500MB VORTICITY
SPREADS NORTH WHILE THE SHORT WAVE TROUGH MOVES THROUGH THE EASTERN
HALF OF THE AREA.
LATE THURSDAY MORNING AND THROUGH THE AFTERNOON SOUTH WINDS WILL STRENGTHEN
FOR LOCATIONS GENERALLY EAST OF A RUSSELL SPRINGS TO MCCOOK LINE AHEAD
OF A SURFACE TROUGH OF LOW PRESSURE. 850MB WINDS OF 20 TO 30 KTS
WILL MIX DOWN TO THE SURFACE AHEAD OF THE SURFACE TROUGH PRODUCING
GUSTS UP TO 40 MPH FOR THE ABOVE LOCATIONS. THE WINDS WILL DECLINE
DURING THE LATE AFTERNOON AS THE STRONGER WINDS MOVE EAST OF THE
AREA. SEE FIRE WEATHER SECTION FOR FIRE WEATHER INFORMATION.
FOR THE FRIDAY THROUGH TUESDAY PERIOD AN UPPER LEVEL SHORT WAVE
TROUGH WILL MOVE THROUGH THE AREA SATURDAY WITH ANOTHER ON MONDAY.
THE STRONGEST SHORT WAVE WILL MOVE THROUGH ON SATURDAY ACCOMPANIED
BY A COLD FRONT. AS A RESULT THE BEST CHANCE FOR PRECIPITATION WILL
BE SATURDAY...MAINLY TIED TO THE FRONTAL PASSAGE. A DRY SLOT WILL
MOVE OVER THE SOUTHERN PART OF THE AREA SATURDAY...DIMINISHING
PRECIPITATION CHANCES FOR THAT AREA. A MINOR SHORT WAVE THROUGH
WILL MOVE THROUGH THE AREA MONDAY...SO HAVE SLIGHT CHANCES IN PLACE
ACROSS MOST OF THE AREA.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 546 PM MDT TUE MAY 15 2012
WEAK SURFACE FRONT WILL CONTINUE TO SLIDE SOUTH INTO THE FORECAST
AREA THIS EVENING WITH NORTHEASTERLY/EASTERLY WINDS EXPECTED TO
GRADUALLY VEER TO THE SOUTHEAST DURING THE DAY WEDNESDAY. COULD
SEE A FEW GUSTS IN EXCESS OF 20KTS THROUGH THE LATE AFTERNOON
HOURS WEDNESDAY WITH JUST A FEW MID-LEVEL CLOUDS EXPECTED. ANY
POTENTIAL FOR CONVECTION SHOULD HOLD OFF UNTIL AFTER THE END OF
THIS EFFECTIVE PERIOD.
&&
.FIRE WEATHER...
ISSUED AT 239 PM MDT TUE MAY 15 2012
FIRE WEATHER WATCH FOR WED WAS UPGRADED TO RED FLAG WARNING...WITH
CONFIDENCE HIGH IN RFW CRITERIA BEING MET. WINDS ACROSS THE
WESTERN HALF OF THE AREA SHOULD BE WELL WITHIN CRITERIA WITH GUSTS
AROUND 35 MPH POSSIBLE. THERE WERE SOME QUESTIONS REGARDING TO
RH...WITH SHORTWAVE TROUGH OVER CENTRAL COLORADO POSSIBLY BRINGING
HIGHER TD VALUES INTO WESTERN PARTS OF CWA. EVEN IF MIXING WERE TO
BE LIMITED IN THE WEST AND TD VALUES REMAIN SLIGHTLY HIGHER...RH
VALUES AROUND 15-17% WOULD STILL BE EXPECTED. BASED ON LOWER MODEL
TRENDS AND BETTER MIXING...CURRENT FORECAST SHOWS RH 12-15%. WITH
WINDS GUSTING AROUND 35 MPH...RFW CRITERIA IS LIKELY UNDER EITHER
SCENARIO.
LOW RELATIVE HUMIDITIES OF 15 TO 20 PERCENT AND STRONG SOUTH WINDS
WITH GUSTS UP TO 40 MPH WILL DEVELOP FOR LOCATIONS EAST OF A
RUSSELL SPRINGS TO MCCOOK LINE THURSDAY AFTERNOON. THESE CONDITIONS WILL
CREATE HAZARDOUS FIRE WEATHER CONDITIONS DURING THE AFTERNOON.
LATEST FUEL STATUS FOR THE NORTON AND HILL CITY AREA WHERE WINDS
WILL BE THE STRONGEST INDICATES THE FUELS ARE STILL GREEN ENOUGH
NOT TO BE A CONCERN...SO WILL NOT BE ISSUING A FIRE WEATHER
HIGHLIGHT AT THIS TIME FOR THURSDAY.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...RED FLAG WARNING FROM 10 AM TO 8 PM MDT WEDNESDAY FOR KSZ013-027.
CO...RED FLAG WARNING FROM 10 AM TO 8 PM MDT WEDNESDAY FOR COZ252>254.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JTL
AVIATION...FOLTZ
FIRE WEATHER...DR/JTL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1125 PM MDT SUN MAY 13 2012
.UPDATE...
ISSUED AT 837 PM MDT SUN MAY 13 2012
JUST ISSUED ANOTHER UPDATE. CURRENT PRECIPITATION FORECAST IS
TRENDING AND MADE NO CHANGES. THERE WAS LITTLE WIND/MIXING THROUGH
THE DAY WITH DEWPOINTS NEARLY THE SAME TODAY AS YESTERDAY. AREA
SOUNDINGS SHOW THAT THE LOW LEVEL MOISTURE HAS ALSO CHANGED LITTLE
ALTHOUGH THE AIR MASS HAS WARMED. WITH A SIMILAR AIR MASS
YESTERDAY THERE WAS SOME MORNING FOG. ALSO CLUSTER OF
THUNDERSTORMS DROPPED A DECENT AMOUNT OF RAINFALL OVER A RATHER
LARGE AREA OVER WESTERN KIT CARSON AND CHEYENNE COUNTIES.
WINDS WILL BE LIGHT AND THEN WILL SHIFT TO THE WEST TO BRING THIS
MOISTURE IN FROM THE WEST. CONSIDERING THE RUC THAT HAS A GOOD
HANDLE ON THE WIND FIELD...DRIER AIR WORKS ITS WAY INTO THE
NORTHEAST HALF OF THE AREA. RUC AND TO A LESSER DEGREE THE ECMWF
INCREASE LOW LEVEL MOISTURE OVER THE SOUTHWEST HALF ALTHOUGH THE
RUC WOULD SAY IT WILL BE STRATUS. AS A RESULT...ADDED PATCHY TO
AREAS OF FOG FOR LATER TONIGHT INTO TOMORROW MORNING. LATEST MAV
WAS DOING WELL WITH THE DEWPOINTS AND AS STATED ABOVE USED THE RUC
FOR THE WINDS AND BLENDED THEM WITH REALITY. OVERNIGHT LOWS LOOK
FINE AT THIS TIME.
UPDATE ISSUED AT 623 PM MDT SUN MAY 13 2012
PERSISTENT AND SLOW MOVING CLUSTER OF STORMS LOCATED OVER/NEAR WESTERN
KIT CARSON AT THIS TIME. THIS AREA LOOKS TO BE IN AN AREA OF
SURFACE/MOISTURE CONVERGENCE COMBINED WITH WEAK SHORTWAVE TROUGH
AND DEEPEST MOISTURE. RAISED POPS MUCH HIGHER OUT WEST...EXPANDED
AREA OF THUNDERSTORMS AND PER CONVERGENCE AND QPF FORECASTS...EXTENDED
THUNDERSTORMS UNTIL 06Z. ALSO INCREASED CLOUD COVER OVER THE WEST
AND SOUTHWEST PORTIONS OF THE AREA WHERE CONVECTION IS OCCURRING.
OTHERWISE JUST MADE MINOR ADJUSTMENTS WITH THE REMAINING ELEMENTS.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH MONDAY EVENING)
ISSUED AT 1157 AM MDT SUN MAY 13 2012
SCATTERED TO BROKEN SKY COVER THIS AFTERNOON WILL PERSIST WITH THE
DAYTIME HEATING PRODUCING A WIDESPREAD CU FIELD. EXPECT THIS TO
DISSIPATE RAPIDLY FOLLOWING SUNSET WITH DRYER AIR MOVING IN MONDAY
AND MONDAY NIGHT AS THE RIDGE OF HIGHER PRESSURE MOVES OVER THE
ROCKIES AND HIGH PLAINS REGION. THERE IS SOME CONVECTIVE ACTIVITY
DEVELOPING OVER THE HIGH TERRAIN OF COLORADO THIS AFTERNOON...SO
THERE IS THE POSSIBILITY OF A FEW SHOWERS MAKING THEIR WAY OVER
THE FAR SOUTHWESTERN PORTION OF THE FORECAST AREA LATE THIS
AFTERNOON AND EARLY EVENING. ANY SHOWERS THAT DO MAKE IT THIS FAR
EAST SHOULD DISSIPATE RAPIDLY AFTER 03Z.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 236 PM MDT SUN MAY 13 2012
TUESDAY-TUESDAY NIGHT...SHORTWAVE RIDGE WILL REMAIN IN PLACE THROUGH
TUESDAY NIGHT...WITH LARGE SCALE SUBSIDENCE SUPPORTING DRY
CONDITIONS. MUCH WARMER TEMPERATURES ARE EXPECTED WITH GUIDANCE
CONTINUING TO SUPPORT TEMPS IN THE MID TO UPPER 80S OVER MUCH OF THE
CWA...WITH TEMPS AROUND 90F IN THE EAST.
WEDNESDAY-THURSDAY NIGHT...VERY WARM TEMPERATURES CONTINUE WITH
SOUTHERLY FLOW IN PLACE AND H85 TEMPS AROUND 25C. HIGHS ON WEDNESDAY
AND THURSDAY WILL BE VERY SIMILAR TO TUESDAY...WITH HIGHS OVER MUCH
OF THE CWA IN THE UPPER 80S. H5 RIDGE BEGINS TO BREAK DOWN WEDNESDAY
AS A SHORTWAVE TROUGH MOVES TOWARDS THE INTER-MOUNTAIN WEST/HIGH
PLAINS. STILL SOME RUN-RUN SPREAD BETWEEN GUIDANCE ON
TIMING/POSITION OF THIS FEATURE...WITH 12Z ECMWF SLOWER AND DRIER.
GFS AND NAM STILL SUPPORT TIMING/COVERAGE FROM PREVIOUS FORECAST
WITH THUNDERSTORMS BEGINNING IN EASTERN COLORADO WEDNESDAY AFTERNOON
AND SPREADING EAST ACROSS THE CWA THROUGH THURSDAY. COVERAGE IS
STILL A QUESTION EVEN WITH THE GFS/NAM SOLUTIONS...WITH LIMITED
MOISTURE ADVECTION AND INSTABILITY WEDNESDAY/WEDNESDAY NIGHT. I
KEPT POPS LIMITED TO SLIGHT CHANCE CATEGORY...AND MADE ONLY MINOR
ADJUSTMENTS TO LOCATION OF POPS IN CWA. IF GFS/NAM IS CORRECT THEN
BEST CHANCE FOR PRECIP WITH THIS FEATURE MAY END UP BEING THURSDAY
OVER OUR EASTERN CWA.
FRIDAY-SUNDAY...SUBSIDENCE ASSOCIATED WITH SHORTWAVE RIDGE SHOULD
KEEP FRIDAY WARM AND DRY. PRECIP CHANCES RETURN BY SATURDAY AS SW
FLOW SET UP ACROSS CWA...AND COLD FRONT DROPS SOUTH ACROSS CWA
SUNDAY. THERE IS STILL CONSIDERABLE SPREAD IN UPPER LEVEL PATTERN
BETWEEN OPERATIONAL GUIDANCE...HOWEVER BOTH GFS AND ECMWF SUPPORT
PRECIP CHANCES SATURDAY THROUGH SUNDAY NIGHT. I CONSIDERED RAISING
POPS...HOWEVER WITH SPREAD ON UPPER LEVEL AND SURFACE FEATURES...ITS
DIFFICULT TO PIN DOWN FAVORED LOCATIONS AT THIS TIME. RATHER THAN
STRAY TOO FAR FROM PREVIOUS TRENDS...I KEPT POPS IN SLIGHT
CHANCE/CHANCE CATEGORIES DURING THESE PERIODS TO ACCOUNT FOR MODEL
SPREAD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1121 PM MDT SUN MAY 13 2012
VFR CONDITIONS AND LIGHT WINDS ARE EXPECTED THROUGH THE PERIOD.
SOME FOG IS EXPECTED AROUND KGLD BUT AT THIS TIME DO NOT EXPECT
CREATE BELOW VFR CONDITIONS.
&&
.FIRE WEATHER...
ISSUED AT 236 PM MDT SUN MAY 13 2012
RED FLAG CONDITIONS WILL BE POSSIBLE WEDNESDAY THROUGH FRIDAY WITH
RH VALUES AND WINDS APPROACHING CRITERIA. BEST CHANCE FOR RED FLAG
CRITERIA TO BE MET LOOKS TO BE ON WEDNESDAY AFTERNOON WHEN WINDS
GUSTING OVER 25 MPH WILL BE COMMON ACROSS THE CWA. THERE ARE STILL
QUESTIONS ON HOW LOW RH VALUES WILL BE WEDNESDAY WITH SHORTWAVE
TROUGH MOVING IN FROM THE WEST. IF PROFILES REMAIN DRY ADIABATIC
THROUGH THE AFTERNOON...CURRENT TD/RH FORECAST COULD BE TOO HIGH.
THIS WILL NEED TO BE MONITORED.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...LOCKHART
LONG TERM...DR
AVIATION...BULLER
FIRE WEATHER...DR
AREA FORECAST DISCUSSION...UPDATED
NWS TWIN CITIES/CHANHASSEN MN
706 PM CDT TUE MAY 15 2012
.UPDATE...
UPDATED FOR THE 00Z AVIATION DISCUSSION BELOW. ALSO WE ARE
LOWERING TEMPERATURES TONIGHT ACROSS MUCH OF THE AREA. IN SOUTH
CENTRAL MN...WE`RE ONLY DROPPING THE LOWS A COUPLE DEGREES FROM
THE AFTERNOON FORECAST. FROM WEST CENTRAL MN INTO WEST CENTRAL
WI...MAINLY AREAS NORTH AND EAST OF THE TWIN CITIES...WE LOWERED
OVERNIGHT LOWS BETWEEN 3-6 DEGREES. YESTERDAY...THE SPREAD BETWEEN
THE HIGH AND LOW TEMPERATURE WAS 35-45 DEGREES ACROSS MUCH OF THE
AREA. THE SURFACE HIGH SETTLES IN LATE TONIGHT AND THE WINDS
SHOULD DECOUPLE. THIS COMBINED WITH THE COOL DEWPOINTS SHOULD MAKE
FOR A VERY COOL MORNING. THE COOLEST TEMPS WILL STRETCH FROM
NORTHEAST/NORTH CENTRAL MN...DOWN INTO WEST CENTRAL WI. LOOKS LIKE
WIDESPREAD UPPER 30S BY SUNRISE TOMORROW IN WEST CENTRAL MN AND
PORTIONS OF EAST CENTRAL MN...WITH LOW SPOTS DROPPING INTO THE MID
30S. THE CORE OF THE TWIN CITIES METRO WILL LIKELY REMAIN CLOSER
TO THE MID 40S...ALTHOUGH SOME OF THE SUBURBS COULD DROP TO NEAR
40.
.DISCUSSION...
A FAIRLY PROGRESSIVE UPPER LEVEL PATTERN WILL BE THE RULE ACROSS
THE NORTHERN CONUS OVER THE UPCOMING WEEK. LATEST WATER VAPOR
IMAGERY AND RAP ANALYSES SHOW A BROAD RIDGE OVER THE WEST... WITH
TROUGHING OVER THE EAST. A HEALTHY SHORTWAVE CAN BE SEEN ROTATING
SOUTHEAST ACROSS THE NORTHERN GREAT LAKES AT THE CURRENT TIME.
THIS FEATURE IS HELPING TO ENHANCE THE CU FIELD ACROSS NORTHEAST
MINNESOTA AND NORTHERN WISCONSIN... BUT ANY SHRA ARE STAYING WELL
NORTH AND EAST OF OUR AREA. THE WESTERN RIDGE WILL MOVE EAST OVER
THE NEXT FEW DAYS... GENERALLY BRINGING DRY WEATHER AND A WARMING
TREND. HOWEVER... CHANCES FOR SHRA/TSRA WILL STEADILY INCREASE
DURING THE SECOND HALF OF THE WEEK INTO THE WEEKEND... WITH AN
UPPER TROUGH EVENTUALLY PUSHING THROUGH TOWARD THE END OF THE
WEEKEND... WHICH WILL HELP PUSH A SURFACE LOW AND FRONTAL BOUNDARY
ACROSS THE REGION. FAVORED THE NAM FOR THE SHORT TERM DETAILS...
THEN TRENDED TOWARD A BLEND OF THE PREVIOUS FORECAST AND ECMWF...
WHICH WAS A BIT SLOWER TO KICK THE RIDGE EASTWARD. THE LATEST
ECMWF IS A BIT FASTER HOWEVER... WHICH MAKES THE WEEKEND FORECAST
TRICKY IN TERMS OF PINPOINTING WHEN PCPN IS MOST LIKELY.
SURFACE RIDGE WILL CONTINUE TO BUILD SOUTHEAST ACROSS THE AREA
TONIGHT... FURTHER DRYING OUT DEWPOINTS THROUGH THE EARLY
EVENING... WITH A REASONABLY COOL NIGHT EXPECTED FOR THE OVERNIGHT
HOURS. THE WESTERN PART OF THE AREA SHOULD MANAGE TO GET ON THE
BACKSIDE OF THE RIDGE BY TOMORROW AFTERNOON... WITH SOME RETURN
FLOW WORKING INTO THAT AREA BY EVENING. A BETTER LOW LEVEL JET AND
WARM ADVECTION LOOK TO SETUP ACROSS THE AREA LATER WEDNESDAY
NIGHT AS LOW PRESSURE EDGED OUT INTO THE HIGH PLAINS. A LOOK AT
FORECAST 850-500MB DIFFERENTIAL THETA-E VALUES... 850MB THETA-E
ADVECTION... AND ISENTROPIC ASCENT ON THE 305K SURFACE SUGGEST
THAT ELEVATED SHRA/TSRA MAY INITIALLY GET GOING OVER THE NORTH
CENTRAL PART OF THE AREA... BUT SHOULD WORK ITS WAY SOUTHEAST
THROUGH THE OVERNIGHT AS SATURATION OCCURS SOUTHWARD ALONG THE
ELEVATED FRONTAL BOUNDARY. SOME ACTIVITY SHOULD REMAIN FOCUSED
NEAR THE FRONTAL BOUNDARY THROUGH THE DAY ON THURSDAY INTO
THURSDAY NIGHT AS WARM ADVECTION PERSISTS IN AN AREA OF CONVECTIVE
INSTABILITY. HOWEVER... BY FRIDAY THROUGH FRIDAY NIGHT THE FOCUS OF
THIS ACTIVITY LOOKS LIKE IT SHOULD SHIFT NORTHEAST OF MOST OF THE
AREA... SO TRIMMED BACK POPS DURING THAT TIME FRAME TO MAINLY
INCLUDE ONLY THE FAR NORTHERN PORTION OF THE CWFA. BY SATURDAY WE
WILL START TO FEEL THE INFLUENCE OF THE APPROACHING SURFACE FRONT
AS THE AIRMASS ACROSS THE REGION CONTINUES TO DESTABILIZE... SO
INCREASED POPS ACROSS MUCH OF THE AREA FROM WEST TO EAST. THE
BOUNDARY ITSELF LOOKS TO MOVE ACROSS THE REGION SATURDAY NIGHT OR
EARLY SUNDAY... BUT AT THIS POINT THAT TIMING COULD EASILY SHIFT
FOR 12-24 HOURS... WHICH WILL CERTAINLY HAVE AN IMPACT ON WHEN
WIDESPREAD SHRA/TSRA IS MOST LIKELY... AS WELL AS WHETHER MUCH IF
ANY SEVERE WEATHER WILL OCCUR. THINGS LOOK TO DRY OUT MONDAY AND
TUESDAY IN THE WAKE OF THE FRONT AND UPPER TROUGH... WITH HIGH
PRESSURE QUICKLY SETTLING IN ON MONDAY... THEN THE PROGRESSIVE
PATTERN BRINGING RETURN FLOW BACK INTO THE REGION BY TUESDAY
AFTERNOON.
&&
.AVIATION.../00Z TAF ISSUANCE/
VFR CONDITIONS THROUGH THE TAF. SHOULD LOSE MOST OF THE GUSTS OVER
15KTS BETWEEN 00-01Z AND THE WINDS WILL CONTINUE TO DROP OFF THIS
EVENING. STARTED THE TAF WITHOUT MUCH OF THE GUSTS DUE TO THE
EXPECTED QUICK DISSIPATION. WINDS SHOULD BE NEAR CALM BEFORE
RETURNING TO THE SOUTH AND THE BACK SIDE OF HIGH PRESSURE.
KMSP...WILL SEE THE FREQUENCY OF GUSTS BETWEEN 15-22KTS DROP OFF
BETWEEN 0030Z AND 0100Z...SO VERY SOON. WINDS WILL BE NEAR CALM
FOR THE MORNING RUSH TOMORROW AND EVENTUALLY SEE A NEAR TRUE SOUTH
COMPONENT BY TOMORROW AFTERNOON. VFR CONDITIONS EXPECTED.
OUTLOOK...
THU-FRI...SLIGHT CHANCE OF SHRA/TSRA...MVFR CEILINGS POSSIBLE.
SAT-SUN...SHRA/TSRA LIKELY WITH MVFR/IFR POSSIBLE.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
TRH/CLF
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
636 PM EDT MON MAY 14 2012
.SYNOPSIS...
LOW PRESSURE WILL MOVE UP THE EAST COAST TONIGHT, AND SPREAD RAIN
INTO THE AREA THROUGH TUESDAY, BEFORE ENDING LATE TUESDAY AND
TUESDAY NIGHT. SKIES WILL CLEAR BRIEFLY LATE TUESDAY AND EARLY
WEDNESDAY AHEAD OF A COLD FRONT. THIS FRONT WILL MOVE THROUGH LATE
WEDNESDAY WITH SHOWERS. HIGH PRESSURE WILL BUILD IN BEHIND THE
FRONT AND BRING DRY WEATHER FOR THE END OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
625 PM UPDATE...
MINOR ADJUSTMENTS...MOSTLY FOR THE SPEED AND COVERAGE OF THE RAIN.
IN GENERAL FORECAST ON TRACK. RAINFALL AMOUNTS SO FAR UNDER AN
INCH.
PREVIOUS DISCUSSION...
MODELS STILL RESOLVING THE UPCOMING RAIN EVENT. OPERATIONAL NAM
HAS GONE BACK TO IT/S EARLIER SOLN AND BRINGS RAIN BACK TO THE
WEST WITHOUT GENERATING THE QPF BULLSEYE OVER THE ERN ZONES. SREF
MEAN SOLN IS MORE IN LINE WITH THE OPERATIONAL GFS WHICH HAS A
PCPN MAX OVER THE UPSLOPE AREAS IN THE CATSKILLS AND POCONOS.
HWVR...GFS MAX ACCUMULATED QPF OF OVER 4.5 INCHES SEEMS TOO
HIGH...AND MODEL MAY BE SUFFERING FROM CONV FEEDBACK WITH STRONG
STORMS FIRING OVER THE SE. SYSTEM HAS GOOD JET STRUCTURE WITH UPR
DIVERGENCE IN THE RR QUAD AND GOOD LL SLY INFLOW. PWATS APRCHS 2"
OVER THE EAST CST...A BIT LESS OVER THE FCST AREA.
CONSENSUS AVGD QPF PUTS 30 HR AMTS OVER THE WRN CATS APRCHG 2
INCHES...WELL BLO FFG AND HEADWATERS GUID. AREA HAS ACTUALLY BEEN A
BIT DRY AND HAS SOME OF THE HIGHEST GUID IN THEN FCST AREA.
SO...AFTER XTNSV COORD WITH SURROUNDING OFFICES HAVE DECIDED TO
HOLD OFF ON A WATCH ATTM. WILL KEEP HWO GOING WITH A MENTION OF
PTNL PRBLMS IF AMTS ARE HIGHER.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
OLD FNT IS SLOW TO MVE AS YET ANOTHER WV RIDES UP ON TUE...SLOWING
THE EWRD ADVANCE. LOOKS LIKE SOME HEAVIER RAIN COULD LINGER IN THE
EAST THRU ABT 18Z TUE AS THE WV PASSES. STILL...BNDRY REMAINS
NEARLY STATIONARY INTO EARLY WED BEFORE A STRONGER SHRT WV AND
SFC FNT APRCHS FROM THE WEST AND PUSHES IT ALONG.
WED/S FNT DOES NOT HAVE THE MOISTURE CONNECTION THAT TUE/S
DOES...SO DESPITE GOOD LL CONVERGENCE AND SUPPORT ALOFT...FNT MAY
NOT GENERATE ALL THAT MUCH PCPN. SOME MRGNL INSTABILITY DOES BRING
THE CHANCE OF CONV WITH THE FNT...ESP OVER THE NORTH NEAR THE
BETTER DYNAMICS AND SOME POOLED LL MOISTURE.
MUCH COOLER AND DRIER AIR FOLLOWS THE FNT ON THU AS A SFC HIPRES
BLDS INTO THE OH VLY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
IMPRVMNT WITH A WARMING TREND FOR THE MEDIUM RNG AS THE NE U.S.
TROF BEGINS TO PULL OUT AND UPR LVL/SFC RIDGING COMMENCES. BY
LATER IN THE WEEKEND THE PTRN DOES BCM MORE FVRBL FOR THE DVLPMNT
OF SOME ISOLD/WDLY SCT -TSRA MAINLY DUE TO DIURNAL EFFECTS...AND
THE PREV 00Z EURO SUGGESTED SOME POTNL FOR MCS ACTIVITY WITH
SYSTEMS DROPPING OUT OF CANADA OVER THE WEEKEND. GFS NOT SHOWING
THIS...AND INDEED HPC POPS INDICATE A DRY FCST UNTIL MONDAY OF NXT
WEEK. WE SEE NO REASON TO TO DISAGREE. WE DID GO MORE OPTIMISTIC
WITH THE SKY COVER THAN THE HPC FCST...WITH GNRLY PARTLY
SUNNY/PARTLY CLOUDY SKIES THRU THE PD.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
WDSPRD RESTRICTIONS ACRS THE FCST AREA THRU 18Z TUE DUE TO
CIGS/RAIN/BR. IT IS A TUFF CALL AT RME/SYR BUT XPCT POTNL FOR MVFR
THIS AFTN...SPCLY AT RME...THEN GNRL MVFR OVRNGT WITH THESE SITES
ON THE PERIPHERY OF THE STEADIER RAIN SHIELD. OTRW...IFR (PSBL
LIFR AT ITH/BGM/AVP) AND SOME MVFR IN RAIN AND MIST. HEAVIER RAINS ARE
XPCTD TO PULL OUT ON TUE MRNG...BUT LOW CIGS AND BR XPCTD TO
PERSIST THRU 18Z. WINDS THIS AFTN GNRLY S TO SE ARND 5 KTS...THEN
SELY 5-10 KTS TNGT INTO MON MRNG.
.OUTLOOK...
TUE NGT...LINGERING MVFR AT AVP...VFR ELSEWHERE WITH PONTL FOR VLY
FOG LATE AFFECTING ELM.
WED...MAINLY VFR...WDLY SCT AFTN -TSRA WITH MVFR PSBL.
THU/FRI/SAT...VFR...XCPT LATE NGT VLY FOG AFFECTING ELM.
&&
.HYDROLOGY...
IN GENERAL FLASH FLOOD AND HEADWATER GUID BLO FCSTD QPF FROM
NEARLY ALL SOURCES. OUTLIER IS THE GFS WICH DROPS A 30 HR TTL OF
ARND 4.5 INCHES OVER THE UPR DELAWARE BASIN. THAT AMT WLD CAUSE
FLOODING ISSUES BUT CONSENSUS IS THAT THE MODEL IS SUFFERING SOME
CONV FEEDBACK ISSUES. HWVR...PLACEMENT FROM THE GFS SEEMS CORRECT
SO BEST LOCATION FOR THE HIGHEST QPF APPEARS TO BE OVER ERN
DELAWARE AND NRN SULLIVAN...IN THE DELAWARE BASIN. HERE THE TOTAL QPF
IS 2 TO 2.5 INCHES WHICH COULD CAUSE MINOR FLOODING OF THE
FLASHIER CREEKS AND STREAMS SUCH AS THE WEST BRANCH AT WALTON. TO
THE WEST OVER THE UPR AND NORTH BRANCH SUSQ BASINS...AVERAGED
AMTS WILL BE LESS SO RVRS SHD STAY WELL BLO FLOOD STAGE. FOR THE
FINGER LAKES AND CHEMUNG BASINS AMOUNTS AN INCH OR LESS SO NO
PROBLEMS EXPECTED.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DGM
NEAR TERM...DGM/TAC
SHORT TERM...DGM
LONG TERM...
AVIATION...
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
326 PM EDT MON MAY 14 2012
.SYNOPSIS...
LOW PRESSURE WILL MOVE UP THE EAST COAST TONIGHT AND SPREAD RAIN
INTO THE AREA THROUGH TUESDAY. SKIES WILL CLEAR BRIEFLY LATE
TUESDAY AND EARLY WEDNESDAY AHEAD OF A COLD FRONT. THIS FRONT WILL
MOVE THROUGH LATE WEDNESDAY. HIGH PRESSURE WILL BUILD IN BEHIND
THE FRONT AND BRING DRY WEATHER FOR THE END OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
MODELS STILL RESOLVING THE UPCOMING RAIN EVENT. OPERATIONAL NAM
HAS GONE BACK TO IT/S EARLIER SOLN AND BRINGS RAIN BACK TO THE
WEST WITHOUT GENERATING THE QPF BULLSEYE OVER THE ERN ZONES. SREF
MEAN SOLN IS MORE IN LINE WITH THE OPERATIONAL GFS WHICH HAS A
PCPN MAX OVER THE UPSLOPE AREAS IN THE CATSKILLS AND POCONOS.
HWVR...GFS MAX ACCUMULATED QPF OF OVER 4.5 INCHES SEEMS TOO
HIGH...AND MODEL MAY BE SUFFERING FROM CONV FEEDBACK WITH STRONG
STORMS FIRING OVER THE SE. SYSTEM HAS GOOD JET STRUCTURE WITH UPR
DIVERGENCE IN THE RR QUAD AND GOOD LL SLY INFLOW. PWATS APRCHS 2"
OVER THE EAST CST...A BIT LESS OVER THE FCST AREA.
CONSENSUS AVGD QPF PUTS 30 HR AMTS OVER THE WRN CATS APRCHG 2
INCHES...WELL BLO FFG AND HEADWATERS GUID. AREA HAS ACTUALLY BEEN A
BIT DRY AND HAS SOME OF THE HIGHEST GUID IN THEN FCST AREA.
SO...AFTER XTNSV COORD WITH SURROUNDING OFFICES HAVE DECIDED TO
HOLD OFF ON A WATCH ATTM. WILL KEEP HWO GOING WITH A MENTION OF
PTNL PRBLMS IF AMTS ARE HIGHER.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
OLD FNT IS SLOW TO MVE AS YET ANOTHER WV RIDES UP ON TUE...SLOWING
THE EWRD ADVANCE. LOOKS LIKE SOME HEAVIER RAIN COULD LINGER IN THE
EAST THRU ABT 18Z TUE AS THE WV PASSES. STILL...BNDRY REMAINS
NEARLY STATIONARY INTO EARLY WED BEFORE A STRONGER SHRT WV AND
SFC FNT APRCHS FROM THE WEST AND PUSHES IT ALONG.
WED/S FNT DOES NOT HAVE THE MOISTURE CONNECTION THAT TUE/S
DOES...SO DESPITE GOOD LL CONVERGENCE AND SUPPORT ALOFT...FNT MAY
NOT GENERATE ALL THAT MUCH PCPN. SOME MRGNL INSTABILITY DOES BRING
THE CHANCE OF CONV WITH THE FNT...ESP OVER THE NORTH NEAR THE
BETTER DYNAMICS AND SOME POOLED LL MOISTURE.
MUCH COOLER AND DRIER AIR FOLLOWS THE FNT ON THU AS A SFC HIPRES
BLDS INTO THE OH VLY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
IMPRVMNT WITH A WARMING TREND FOR THE MEDIUM RNG AS THE NE U.S.
TROF BEGINS TO PULL OUT AND UPR LVL/SFC RIDGING COMMENCES. BY
LATER IN THE WEEKEND THE PTRN DOES BCM MORE FVRBL FOR THE DVLPMNT
OF SOME ISOLD/WDLY SCT -TSRA MAINLY DUE TO DIURNAL EFFECTS...AND
THE PREV 00Z EURO SUGGESTED SOME POTNL FOR MCS ACTIVITY WITH
SYSTEMS DROPPING OUT OF CANADA OVER THE WEEKEND. GFS NOT SHOWING
THIS...AND INDEED HPC POPS INDICATE A DRY FCST UNTIL MONDAY OF NXT
WEEK. WE SEE NO REASON TO TO DISAGREE. WE DID GO MORE OPTIMISTIC
WITH THE SKY COVER THAN THE HPC FCST...WITH GNRLY PARTLY
SUNNY/PARTLY CLOUDY SKIES THRU THE PD.
&&
.AVIATION /19Z MONDAY THROUGH SATURDAY/...
WDSPRD RESTRICTIONS ACRS THE FCST AREA THRU 18Z TUE DUE TO
CIGS/RAIN/BR. IT IS A TUFF CALL AT RME/SYR BUT XPCT POTNL FOR MVFR
THIS AFTN...SPCLY AT RME...THEN GNRL MVFR OVRNGT WITH THESE SITES
ON THE PERIPHERY OF THE STEADIER RAIN SHIELD. OTRW...IFR (PSBL
LIFR AT ITH/BGM/AVP) AND SOME MVFR IN RAIN AND MIST. HEAVIER RAINS ARE
XPCTD TO PULL OUT ON TUE MRNG...BUT LOW CIGS AND BR XPCTD TO
PERSIST THRU 18Z. WINDS THIS AFTN GNRLY S TO SE ARND 5 KTS...THEN
SELY 5-10 KTS TNGT INTO MON MRNG.
.OUTLOOK...
TUE NGT...LINGERING MVFR AT AVP...VFR ELSEWHERE WITH PONTL FOR VLY
FOG LATE AFFECTING ELM.
WED...MAINLY VFR...WDLY SCT AFTN -TSRA WITH MVFR PSBL.
THU/FRI/SAT...VFR...XCPT LATE NGT VLY FOG AFFECTING ELM.
&&
.HYDROLOGY...
FFG AND HEADWATER GUID BLO FCSTD QPF FROM NEARLY ALL SOURCES.
OUTLIER IS THE GFS WICH DROPS A 30 HR TTL OF ARND 4.5 INCHES OVER
THE UPR DELAWARE BASIN. THAT AMT WLD CAUSE FLOODING ISSUES BUT
CONSENSUS IS THAT THE MODEL IS SUFFERING SOME CONV FEEDBACK
ISSUES. HWVR...PLACEMENT FROM THE GFS SEEMS CORRECT SO BEST
LOCATION FOR THE HIGHEST QPF APPEARS TO BE OVER ERN DELAWARE AND
NRN SULLIVAN...IN THE DELAWARE BASIN. TO THE WEST OVER THE UPR
SUSQ BASIN...AVERAGED AMTS WILL BE CONSIDERABLY LESS SO RVRS SHD
STAY WELL BLO FLOOD STAGE.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DGM
NEAR TERM...DGM
SHORT TERM...DGM
LONG TERM...
AVIATION...
HYDROLOGY...DGM
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
731 PM EDT TUE MAY 15 2012
.SYNOPSIS...
A VERY SLOW MOVING COLD FRONT WILL BE A FOCUS FOR SHOWERS AND
THUNDERSTORMS TODAY...WITH A FEW THUNDERSTORMS PRODUCING HEAVY
RAIN AND GUSTY WINDS. SHOWERS AND THUNDERSTORMS WILL DEVELOP AGAIN
WEDNESDAY BEFORE COLD FRONT MOVES OFFSHORE WEDNESDAY NIGHT. HIGH
PRESSURE WILL BUILD INTO THE REGION THURSDAY...BRINGING DRIER AND
SEASONABLE WEATHER INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 2:00 PM TUESDAY...STATIONARY FRONT REMAINS TO THE WEST AS A
BROAD SOUTHWESTERLY FLOW CONTINUES ALOFT. SEA BREEZE CONVECTION
HAS FIRED AND SPC MESO-ANALYSIS PAGE SHOWS MIXED LAYER CAPE VALUES
NEAR 2000 J/KG INLAND. SHOULD SEE CONVECTION FIRE SHORTLY IN THESE
AREAS AS HEATING CONTINUES. GFS HAS BACKED OFF THE POPS INLAND FOR
OVERNIGHT BUT THE NAM AND HRRR CONTINUE TO BE QUITE AGGRESSIVE.
BACKED OFF POPS SLIGHTLY BUT WILL CONTINUE TO ADVERTISE LIKELY
VALUES MAXIMIZED AROUND 0000 UTC ACROSS WESTERN COUNTIES WITH
CHANCE ELSEWHERE. LATEST SPC DAY ONE OUTLOOK HAS NOT CHANGED FROM
EARLIER VERSIONS. FOR OVERNIGHT LOWS...WITH THE TROPICAL AIRMASS
IN PLACE CONTINUED TO GO WARMER THAN GUIDANCE.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 2:00 PM TUESDAY...COLD FRONT WILL REMAIN A FOCUS FOR
CONVECTION ON WEDNESDAY AS IT MOVES SLOWLY SOUTHEAST ACROSS THE
FORECAST AREA. AIR MASS WILL REMAIN JUICY AND WARM AND AT LEAST
MARGINALLY UNSTABLE...WITH DEW POINTS WELL IN THE 60S AND P/W
VALUES OF AROUND AN INCH AND A HALF. FRONT SHOULD MOVE OFFSHORE
AROUND DAYBREAK ON THURSDAY.
LATEST GUIDANCE HINTS AT FRONT LINGERING JUST OFFSHORE INTO THE
DAYLIGHT HOURS ON THURSDAY AS AN UPPER WEAKNESS LINGERS OVER THE
EASTERN CAROLINAS. THIS WILL KEEP IN THE POSSIBILITY OF
CONVECTION ON THURSDAY...ESPECIALLY FOR THE COASTAL COUNTIES.
MODEL SOUNDINGS ALSO KEEP IN DEEP MOISTURE FOR MUCH OF THAT DAY.
HAVE RAMPED UP POPS FOR THURSDAY AS A RESULT...ALTHOUGH CONFIDENCE
NOT HIGH AT THIS POINT.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 300 AM TUESDAY...THERE ARE TWO GUIDANCE CAMPS FOR THE
EXTENDED. THE GFS/CMC DEVELOP ELONGATED RIDGING ACROSS THE OH VLY
WITH A BAGGY TROUGH PERSISTING FROM THE WESTERN ATLANTIC INTO
FLORIDA...WHILE THE ECMWF STILL DEVELOPS A CLOSED UPPER LOW OVER THE
WESTERN ATLANTIC ABOVE A HYBRID SURFACE CYCLONE. ALTHOUGH THE ECMWF
HAS BEEN SHOWING THIS FOR SEVERAL RUNS...WEAKER BLOCKING UPSTREAM
COMBINED WITH THE VERY SIMILAR GFS/CMC AND OVERALL DRIER FORECAST
PROFILES SUGGEST MUCH LESS CHANCE OF HYBRID CYCLONE DEVELOPMENT.
STILL...SOME LOWERED HEIGHTS TROUGHING BACK TOWARDS THE SOUTHEAST
SUGGEST THAT THE GFS IS NOT GIVING UP ON THIS SOLUTION
ENTIRELY...AND EVEN SO...WOULD NOT JUMP EXCLUSIVELY ON THE CMC/GFS
BANDWAGON SINCE THIS MARKS A LARGE DEPARTURE FROM PREVIOUS
SOLUTIONS. HOWEVER...WILL GO WITH A DRY FORECAST THROUGH THE PERIOD
THANKS TO SURFACE RIDGING PERSISTING FROM THE NORTH...AND THE NOW
EXPECTED DRY/STABLE LAYERS ABOVE THE SURFACE.
WITH NE FLOW THROUGH THE PERIOD...TEMPS WILL REMAIN RIGHT AROUND
CLIMO FOR BOTH HIGHS AND LOWS...EVEN AS THICKNESSES BEGIN TO RETURN
TO MORE SUBTROPICAL LEVELS. SOME PRECIP MAY AGAIN APPROACH THE
REGION MONDAY...BUT FOR NOW WILL KEEP POP OUT OF THE FORECAST 7 DAYS
OUT.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
AS OF 00Z...AT FLO OVER THE NEXT HOUR OR TWO THERE IS MODERATE
CONFIDENCE THAT THUNDERSTORMS/TEMPO MVFR CONDITIONS WILL AFFECT
THE TERMINAL. THE REMAINING TERMINALS SHOULD REMAIN THUNDERSTORM
FREE.
AT CRE/MYR THERE IS A POSSIBILITY OF LOW MVFR/IFR CEILINGS THIS
EVENING. CONFIDENCE IS LOW AS TO ANY SUSTAINED PERIOD OF CEILINGS.
AFTER MIDNIGHT THERE IS A CHANCE FOR MVFR VISIBILITIES IN BR AT
FLO/LBT. AS LONG AS CLOUD COVER REMAINS BROKEN IFR POTENTIAL
SHOULD REMAIN LOW. MODELS ARE SUGGESTING SHOWERS AND POSSIBLY
THUNDERSTORMS WILL RE-DEVELOP OVERNIGHT NEAR FLO AND MOVE TO NEAR
LBT BY SUNRISE. CONFIDENCE IS LOW AS TO THUNDERSTORM DEVELOPMENT
SO WILL JUST INDICATE TEMPO SHRA AND RE-EVALUATE THUNDERSTORM
POTENTIAL ON THE NEXT TAF ISSUANCE.
WITH A COLD FRONT APPROACHING AND THE SEA BREEZE EXPECT A GOOD
CHANCE OF SHOWERS/SCATTERED THUNDERSTORMS DURING THE DAY. TEMPO
PERIODS OF MVFR/IFR WILL BE POSSIBLE. HAVE USED CONTINUITY FOR
ACTIVITY AT THE COASTAL TERMINALS.
EXTENDED OUTLOOK...UNSETTLED WEATHER THROUGH THURSDAY WITH A GOOD
CHANCE FOR SHOWERS/ISOLATED THUNDERSTORMS/TEMPO MVFR. VFR FRIDAY
THROUGH SUNDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 2:00 PM TUESDAY...SUMMERTIME PATTERN CONTINUES ACROSS THE
COASTAL WATERS WITH THE SOUTH TO SOUTHWESTERLY FLOW BETWEEN A WEAK
STATIONARY FRONT TO THE WEST AND BERMUDA HIGH PRESSURE TO THE
EAST. WILL PROBABLY SEE A SIMILAR PATTERN OF WINDS BACKING OFF A
COUPLE OF KNOTS LATE TONIGHT TO NEAR TEN KNOTS AS THE GRADIENT
DECREASES SLIGHTLY. SEAS REMAIN CONSISTENT AS WELL WITH 2-4 FEET.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 2:00 PM TUESDAY...A COLD FRONT WILL DROP SLOWLY SOUTHEAST
ACROSS THE CAROLINAS ON WEDNESDAY...MOVING ACROSS THE WATERS ON
THURSDAY MORNING. SLACK GRADIENT WILL KEEP WINDS LIGHT AND
SOUTHERLY UNTIL THEN...MAINLY IN THE 10 TO 15 KT RANGE...WITH SEAS
IN THE 3 TO 4 FT RANGE. WINDS WILL SHIFT NE ON
THURSDAY...INCREASING TO AROUND 15 KTS LATE OVERNIGHT. SEAS WILL
BE IN THE 2 TO 4 FT RANGE FOR MUCH OF THURSDAY.
LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 3:00 AM TUESDAY...HIGH PRESSURE RIDGING DOWN THE EAST COAST
WILL KEEP MODERATE-TO-STRONG NE WINDS THROUGH THE PERIOD. WINDS OF
15-20 KTS...WITH ONLY MINOR DIURNAL VARIATIONS...WILL OCCUR THROUGH
SATURDAY. ALTHOUGH A WEAK SE SWELL WILL PERSIST...THE SIGNIFICANT
WAVES WILL BE A NE WIND CHOP OF 5FT/5SEC WHICH BUILDS SEAS TO 4-5 FT
FRIDAY...WITH 6 FT SEAS DEVELOPING ON SATURDAY. CAUTIONARY HEADLINES
ARE LIKELY FRIDAY...WITH SCA CONDITIONS POSSIBLE FOR THE WEEKEND.
ONCE AGAIN...THERE WILL BE A SIGNIFICANT SHADOW REGION SW OF FRYING
PAN SHOALS...WHERE SEAS WILL PERSIST AT ONLY 1-3 FT IN THE INNER 10
NM OF AMZ252 AND AMZ254.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...SHK
SHORT TERM...REK
LONG TERM...JDW
AVIATION...MRR
MARINE...REK/JDW/SHK
AREA FORECAST DISCUSSION
NWS RALEIGH NC
210 AM EDT MON MAY 14 2012
.SYNOPSIS...
AN UPPER LEVEL TROUGH AND ASSOCIATED SURFACE LOW PRESSURE SYSTEM
WILL SLOWLY PROGRESS EAST TOWARD THE SOUTHEAST COAST THROUGH MID
WEEK...RESULTING IN AN EXTENDED PERIOD OF UNSETTLED WEATHER.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 925 PM SUNDAY...
FOR THE REST OF TONIGHT: THE MID LEVEL TROUGH AXIS EXTENDS FROM LAKE
HURON THROUGH INDIANA TO THE LOWER OH VALLEY AND MS THIS EVENING...
AND NUMEROUS MINOR PERTURBATIONS CONTINUE TO TRACK UP THE EAST SIDE
OF THE TROUGH THROUGH WESTERN/CENTRAL NC. THIS WEAK BUT PERSISTENT
DPVA AND A SUBTLE DISSIPATING POCKET OF UPPER DIVERGENCE AS WELL
AS DEEPENING AND STRENGTHENING ISENTROPIC UPGLIDE THROUGH 295K-
310K ACTING ON COPIOUS MOISTURE (PRECIPITABLE WATER HAS RISEN FROM
JUST BELOW NORMAL TO NEARLY 150% OF NORMAL SINCE THIS MORNING) HAS
PRODUCED WIDESPREAD LIGHT RAIN AND DRIZZLE OVER CENTRAL NC SINCE
LATE AFTERNOON... PARTICULARLY ON THE WESTERN PIEDMONT. THIS LIGHT
RAIN/DRIZZLE AREA... COINCIDENT WITH ONE PARTICULAR BETTER-DEFINED
MID LEVEL WAVE... WILL CONTINUE TO MOVE TOWARD THE NORTH NORTHEAST
OVER THE NEXT SEVERAL HOURS... AND WILL LIKELY BE FOLLOWED BY A
BREAK IN STEADY PRECIPITATION FROM SSW TO NORTH NORTHEAST
OVERNIGHT... AS NOTED ON THE HRRR MODEL WHICH IS HANDLING THE
CURRENT PRECIPITATION WELL. BUT WITH STEADY ADVECTION IN THE
LOWEST 3 KM OF WARM AND VERY MOIST AIR... AND CONVERGENT FLOW AT
850 MB THROUGH THE CENTRAL CAROLINAS EVIDENT ON 00Z UPPER AIR
ANALYSES... THE CHANCES FOR MORE PRECIPITATION OVERNIGHT ARE QUITE
HIGH... ESPECIALLY OVER THE WESTERN PIEDMONT GIVEN MODEL
INDICATIONS OF SUBSTANTIAL LOW LEVEL MOISTURE TRANSPORT CONTINUING
IN THIS AREA THROUGH DAYBREAK. NOT OVERLY CONCERNED ABOUT MUCH
THUNDER TONIGHT CONSIDERING THE LACK OF MID LEVEL HEIGHT FALLS AND
WEAKENING UPPER LEVEL WIND FIELD... PLUS THE DEEP LAYER SHEAR IS
VERY WEAK AS ARE THE LOW- AND MID-LEVEL LAPSE RATES. BUT
CONSIDERING THE INCOMING PUNCH OF MID LEVEL DRY AIR NOTED ON WATER
VAPOR IMAGERY AND 00Z SOUNDINGS FROM THE DEEP SOUTH AND WESTERN
GULF COAST... POCKETS OF BETTER (YET STILL VERY MODEST)
DESTABILIZATION REMAIN POSSIBLE AND THE RISK OF ISOLATED THUNDER
WILL BE RETAINED OVERNIGHT. WITH THE LIGHT NATURE OF THE
PRECIPITATION SO FAR AND EXPECTED SPOTTY NATURE OF ADDITIONAL
SHOWERS AND ISOLATED STORMS OVERNIGHT... HAVE CUT BACK FORECAST
PRECIPITATION AMOUNTS THROUGH DAWN TO NO MORE THAN A THIRD OF AN
INCH WEST TO JUST A FEW HUNDREDTHS EAST... ALTHOUGH THE THREAT OF
HEAVIER RAIN ON MONDAY STILL APPEARS ON TRACK. EXPECT NEARLY
STEADY TEMPS IN THE 60-65 RANGE OVER MUCH OF THE AREA FOR THE REST
OF THE NIGHT. -GIH
&&
.SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY NIGHT/...
AS OF 235 PM SUNDAY...
MONDAY AND MONDAY NIGHT:
BROAD UPPER-LEVEL TROUGH IN PLACE FROM THE GREAT LAKES TO THE LOWER
MS VALLEY WILL GET REINFORCED BY SHORTWAVE TROUGH DIVING SOUTHEAST
ALONG THE SOUTHERN ROCKIES AND INTO THE SOUTHERN PLAINS ON MONDAY.
MEANWHILE...WEAK FRONTAL ZONE AND ASSOCIATED WAVE OF LOW PRESSURE
OVER THE SOUTHERN APPALACHIANS WILL INCH SLOWLY EASTWARD INTO THE
WESTERN CAROLINAS THROUGH MONDAY NIGHT. SHORTWAVE ENERGY IS EXPECTED
TO EJECT EAST-NORTHEASTWARD ACROSS THE AREA IN THE SOUTHWEST FLOW
ALOFT DOWNSTREAM OF THE BROAD TROUGH AND WITHIN THE ANOMALOUSLY
HIGH (2 STD ABOVE NORMAL)PRECIPITABLE WATER AIR MASS LYING ALONG
AND EAST OF THE WEAK FRONTAL ZONE ACROSS WESTERN NC. DAYTIME
HEATING OF THE MOIST BOUNDARY LAYER WILL SUPPORT NUMEROUS TO
WIDESPREAD SHOWERS/THUNDERSTORMS MONDAY AFTERNOON/EVENING...WITH
AN AXIS OF MODERATE TO HEAVY RAINFALL NOT BUDGING VERY
MUCH...CENTERED ALONG AND ON THE EASTERN SLOPES OF THE
APPALACHIANS AND POTENTIALLY EXTENDING EAST INTO THE WESTERN
PIEDMONTS OF NC AND VIRGINIA. WHILE THERE REMAINS SOME UNCERTAINTY
WITH REGARD TO TO THE TIMING OF THE EMBEDDED SHORTWAVE
IMPULSES...MODEL CONSENSUS INDICATES THAT THE HEAVY RAINFALL AXIS
AND HIGHEST WILL SHIFT EASTWARD MONDAY NIGHT...REACHING THE
COASTAL SECTIONS BY DAYBREAK TUESDAY.
SEVERE WEATHER THREAT:
WHILE MOIST ADIABATIC PROFILES WILL SUPPORT WEAK MID-LEVEL LAPSE
RATES AND INSOLATION SHOULD BE GREATLY IMPEDED BY WIDESPREAD
CLOUDS...MODELS STILL SUGGEST THE POTENTIAL FOR WEAK TO MODERATE
DESTABILIZATION COULD DEVELOP MONDAY AFTERNOON. UNIDIRECTIONAL
SOUTHWEST FLOW OF 25-30 KT COULD SUPPORT A CLUSTER OR TWO OF
STRONG TO SEVERE THUNDERSTORMS THAT COULD PRODUCE DAMAGING WET
MICROBURSTS. WITH LOSS OF DAYTIME HEATING ...THE THREAT OF SEVERE
WEATHER SHOULD BE ON THE WANE MONDAY NIGHT AS THE AIR MASS
COOLS/STABILIZES.
HEAVY RAIN THREAT:
WHILE IT WILL GREATLY DEPEND ON HOW MUCH RAINFALL WE SEE THIS
AFTERNOON AND TONIGHT...THE WESTERN PIEDMONT/TRIAD AREA COULD
POTENTIALLY ADD ANOTHER 1 TO 2 INCHES MONDAY AND MONDAY NIGHT TO
WHATEVER WE SEE TONIGHT. 3 HOUR FLASH FLOOD GUIDANCE TODAY FOR THOSE
AREAS ARE AROUND 3.0"...BUT IF WE RECEIVE AN INCH OF RAIN
TONIGHT...IT SHOULD LOWER THE GUIDANCE SIGNIFICANTLY...CLOSE TO THE
TWO INCH THRESHOLD. LATER SHIFTS MAY NEED TO CONSIDER A FLASH FLOOD
WATCH FOR THE WESTERN PIEDMONT MONDAY AFTERNOON/MONDAY NIGHT. EAST
OF THE TRIAD...EXPECT AVERAGE RAINFALL AMOUNTS OF 0.50-1.0"... WITH
ONLY LOCALIZED/URBAN FLOODING EXPECTED.
TEMPERATURES:
HIGHS MONDAY WILL DEPEND ON SHOWER/STORM COVERAGE AND WHETHER WE
WILL MANAGE TO SEE ANY BREAKS IN THE EAST. AFTERNOON HIGHS RANGING
FROM AROUND 70 WEST TO AROUND 80 EAST. LOWS MONDAY NIGHT AGAIN
IN THE 60S. -CBL
TUESDAY AND TUESDAY NIGHT:
ONGOING SHOWERS AND STORMS TUESDAY MORNING SHOULD BE MOVING INTO THE
COASTAL PLAIN AS THE AXIS OF DEEPEST MOISTURE FINALLY SHIFTS TOWARD
THE COAST. HOWEVER...THE WEAK SURFACE FRONT IS FORECAST LINGER BACK
TO THE WEST ALONG THE MOUNTAINS WHILE THE UPPER TROUGH ENERGY
CONTINUES TO EVOLVE WEST OF THE MOUNTAINS....EVENTUALLY PUSHING INTO
THE AREA TUESDAY EVENING. WITH SLIGHTLY DRIER AIR FORECAST TO
OVERSPREAD CENTRAL NC...SOME BREAKS IN CLOUD COVER AND STRONGER
DESTABILIZATION ARE EXPECTED. AHEAD OF THE UPPER TROUGH... THE MAY
CONTINUE TO BE SUBTLE DISTURBANCES ALOFT MOVING ACROSS THE
PERSISTENT WARM AND MOIST AIR MASS...LEADING TO A SCATTERED SHOWERS
AND STORMS BY TUESDAY AFTERNOON. THE NAM IS STRONGEST AND SHOWING A
STOUT VORTICITY MAX LIFTING ACROSS THE AREA DURING PEAK HEATING. A
TIGHTER HEIGHT FIELD ASSOCIATED WITH THIS FEATURE LEADS TO STRONGER
DEEP LAYER SHEAR FORECAST BY THE NAM...BUT THE NAM SEEMS TO BE
OVERDONE. THE GFS AND ECMWF SHOW MORE A MORE DIFFUSE WAVE AND
ONLY 20-25KT OF 0-6KM BULK SHEAR...WHICH IS SUPPORTED BY MOST SREF
MEMBERS. THERE IS CONSIDERABLE SPREAD AMONG SREF MEMBERS REGARDING
INSTABILITY...BUT MODIFIED GFS SOUNDINGS FOR TEMPS IN THE UPPER 70S
TO LOWER 80S AND DEWPOINTS IN THE LOWER 60S SHOW 500-1000 J/KG OF
MLCAPE. A FEW ISOLATED SEVERE STORMS MAY BE POSSIBLE...BUT IF THE
UPPER WAVE IS STRONGER...AS THE NAM FORECASTS...THEN THE SEVERE
POTENTIAL WILL BE GREATER. HIGHS 77-82.
AS THE SURFACE FRONT AND MAIN LOW LEVEL CONVERGENCE ZONE PUSHES INTO
THE CWA TUESDAY EVENING...ISOLATED SHOWERS AND STORMS MAY CONTINUE
INTO THE OVERNIGHT HOURS. THE FRONT WILL CONTINUE TO BE RATHER SLOW
MOVING...AND LOWS SHOULD BE FAIRLY PERSISTENT IN THE UPPER 50S TO
LOWER 60S.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 205 AM...
A BAGGY UPPER TROUGH IS FORECAST TO BE DROPPING OFF THE MOUNTAINS
INTO THE FOOTHILLS AT SUNRISE WEDNESDAY. PROGRESS IS SLOW WITH THE
TROUGH AXIS NO FURTHER EAST THAN HIGHWAY ONE AT SUNSET. THE GFS
CONTINUES TO BE SHARPEST AND MOST PROGRESSIVE WITH UPPER LEVEL
RIDGING IN THE MIDWEST...SLOWING THE EASTWARD PROGRESS OF THE EAST
COAST TROUGH. THE MAJORITY OF MODELS ARE FLATTER AND FURTHER WEST
WITH MIDWEST RIDGING... WITH THE 850 MILLIBAR TROUGH WELL EAST OF
CENTRAL NORTH CAROLINA BY SUNSET. WILL FAVOR THE CONSENSUS WITH
SLIGHT CHANCES FOR SHOWERS WEDNESDAY MORNING... AND SMALL
AFTERNOON CHANCES FOR THUNDERSTORMS IN THE EAST EXITING DURING
THE EVENING.
WEAK HIGH PRESSURE ADVANCES TOWARD THE MID ATLANTIC STATES WEDNESDAY
NIGHT AND THURSDAY. MID LEVEL FLOW OVER THE CAROLINAS IS WEAK AND
GENERALLY FROM THE WEST TO NORTHWEST. MEASURABLE RAIN CHANCES APPEAR
MINIMAL IN THIS PATTERN AND WILL PLACE CHANCES AT LESS THAN SLIGHT.
1000 TO 850 MILLIBAR THICKNESSES FORECAST TO BE NEAR CLIMATOLOGY.
EXPECT ENOUGH SUNSHINE BOTH DAYS FOR AFTERNOON HIGH TEMPERATURES
SETTLE NEAR CLIMATOLOGY AS WELL... WITH HIGHS IN THE UPPER 70S TO
LOWER 80S. LOW TEMPERATURES WEDNESDAY AND THURSDAY NIGHTS IN THE MID
TO UPPER 50S.
MID LEVEL HIGH PRESSURE OVER TENNESSEE FRIDAY WILL EXPAND TOWARD NEW
ENGLAND DURING THE WEEKEND. A BROAD AREA OF LOW PRESSURE IS EXPECTED
TO BE CENTERED FAR ENOUGH OFF THE CAROLINA COAST TO LEAVE CENTRAL
NORTH CAROLINA DRY FRIDAY INTO SUNDAY. WITH THE WEATHER PATTERN OVER
THE SOUTHEAST SOMEWHAT STATIC AND LOW LEVEL THICKNESSES NEAR
CLIMATOLOGY... TEMPERATURES WILL FOLLOW SUIT. AFTERNOON HIGH
TEMPERATURES IN THE UPPER 80S TO LOWER 80S AND LOWS IN THE UPPER
50S TO LOWER 60S.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 1205 AM MONDAY...
24-HR TAF PERIOD:
DETERIORATING CONDITIONS ARE EXPECTED THIS MORNING...WITH LITTLE (IF
ANY) IMPROVEMENT THROUGH THE REMAINDER OF THE TAF PERIOD. AN UPPER
LEVEL TROUGH AND ASSOCIATED SURFACE LOW PRESSURE SYSTEM WILL
CONTINUE TO SLOWLY APPROACH THE CAROLINAS FROM THE WEST TODAY AND
TONIGHT. PERIODS OF SHOWERS ARE EXPECTED THIS MORNING...WITH
CEILINGS LOWERING TO IFR/LIFR AT THE INT/GSO TERMINALS AND MVFR/IFR
AT THE RDU/FAY/RWI TERMINALS. PERIODS OF SHOWERS AND THUNDERSTORMS
ARE EXPECTED THIS AFTERNOON...WITH ONLY A MARGINAL IMPROVEMENT IN
CEILINGS DURING PEAK HEATING. EXPECT CEILINGS AND VISBYS TO DECREASE
INTO THE IFR/LIFR RANGE EVERYWHERE BETWEEN SUNSET THIS EVENING AND
SUNRISE TUESDAY MORNING. SE/SSE WINDS AT ~5 KT WILL PERSIST THROUGH
SUNRISE...WITH SE/SSE WINDS INCREASING TO ~10 KT BY THIS AFTERNOON.
LOOKING AHEAD:
LINGERING LOW LEVEL MOISTURE COMBINED WITH ANOTHER UPPER LEVEL
TROUGH APPROACHING THE AREA FROM THE NORTHWEST WILL ALLOW ADVERSE
AVIATION CONDITIONS TO PERSIST TUESDAY/TUESDAY NIGHT...WITH
SCATTERED SHOWERS AND THUNDERSTORMS POSSIBLE AT ALL TERMINALS.
IMPROVING CONDITIONS ARE EXPECTED WEDNESDAY/WEDNESDAY NIGHT AS THE
UPPER LEVEL TROUGH AND ASSOCIATED SURFACE LOW PROGRESS CLOSER
TOWARD THE SOUTHEAST COAST... THOUGH MVFR CONDITIONS APPEAR LIKELY
IN MANY LOCATIONS. UNCERTAINTY INCREASES TOWARD THE LATTER PORTION
OF THE WEEK. AT THIS TIME... VFR/MVFR CEILINGS (2500-4500 FT AGL)
ARE EXPECTED THURSDAY/FRIDAY. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...GIH
SHORT TERM...SMITH/CBL
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1213 AM EDT MON MAY 14 2012
.SYNOPSIS...
AN UPPER LEVEL TROUGH AND ASSOCIATED SURFACE LOW PRESSURE SYSTEM
WILL SLOWLY PROGRESS EAST TOWARD THE SOUTHEAST COAST THROUGH MID
WEEK...RESULTING IN AN EXTENDED PERIOD OF UNSETTLED WEATHER.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 925 PM SUNDAY...
FOR THE REST OF TONIGHT: THE MID LEVEL TROUGH AXIS EXTENDS FROM LAKE
HURON THROUGH INDIANA TO THE LOWER OH VALLEY AND MS THIS EVENING...
AND NUMEROUS MINOR PERTURBATIONS CONTINUE TO TRACK UP THE EAST SIDE
OF THE TROUGH THROUGH WRN/CENTRAL NC. THIS WEAK BUT PERSISTENT DPVA
AND A SUBTLE DISSIPATING POCKET OF UPPER DIVERGENCE AS WELL AS
DEEPENING AND STRENGTHENING ISENTROPIC UPGLIDE THROUGH 295K-310K
ACTING ON COPIOUS MOISTURE (PRECIPITABLE WATER HAS RISEN FROM JUST
BELOW NORMAL TO NEARLY 150% OF NORMAL SINCE THIS MORNING) HAS
PRODUCED WIDESPREAD LIGHT RAIN AND DRIZZLE OVER CENTRAL NC SINCE
LATE AFTERNOON... PARTICULARLY ON THE WESTERN PIEDMONT. THIS LIGHT
RAIN/DRIZZLE AREA... COINCIDENT WITH ONE PARTICULAR BETTER-DEFINED
MID LEVEL WAVE... WILL CONTINUE TO MOVE TOWARD THE NNE OVER THE NEXT
SEVERAL HOURS... AND WILL LIKELY BE FOLLOWED BY A BREAK IN STEADY
PRECIP FROM SSW TO NNE OVERNIGHT... AS NOTED ON THE HRRR MODEL WHICH
IS HANDLING THE CURRENT PRECIP WELL. BUT WITH STEADY ADVECTION IN
THE LOWEST 3 KM OF WARM AND VERY MOIST AIR... AND CONVERGENT FLOW AT
850 MB THROUGH THE CENTRAL CAROLINAS EVIDENT ON 00Z UPPER AIR
ANALYSES... THE CHANCES FOR MORE PRECIP OVERNIGHT ARE QUITE HIGH...
ESPECIALLY OVER THE WESTERN PIEDMONT GIVEN MODEL INDICATIONS OF
SUBSTANTIAL LOW LEVEL MOISTURE TRANSPORT CONTINUING IN THIS AREA
THROUGH DAYBREAK. NOT OVERLY CONCERNED ABOUT MUCH THUNDER TONIGHT
CONSIDERING THE LACK OF MID LEVEL HEIGHT FALLS AND WEAKENING UPPER
LEVEL WIND FIELD... PLUS THE DEEP LAYER SHEAR IS VERY WEAK AS ARE
THE LOW- AND MID-LEVEL LAPSE RATES. BUT CONSIDERING THE INCOMING
PUNCH OF MID LEVEL DRY AIR NOTED ON WATER VAPOR IMAGERY AND 00Z
SOUNDINGS FROM THE DEEP SOUTH AND WESTERN GULF COAST... POCKETS OF
BETTER (YET STILL VERY MODEST) DESTABILIZATION REMAIN POSSIBLE AND
THE RISK OF ISOLATED THUNDER WILL BE RETAINED OVERNIGHT. WITH THE
LIGHT NATURE OF THE PRECIP SO FAR AND EXPECTED SPOTTY NATURE OF
ADDITIONAL SHOWERS AND ISOLATED STORMS OVERNIGHT... HAVE CUT BACK
FORECAST PRECIP AMOUNTS THROUGH DAWN TO NO MORE THAN A THIRD OF AN
INCH WEST TO JUST A FEW HUNDREDTHS EAST... ALTHOUGH THE THREAT OF
HEAVIER RAIN ON MONDAY STILL APPEARS ON TRACK. EXPECT NEARLY STEADY
TEMPS IN THE 60-65 RANGE OVER MUCH OF THE AREA FOR THE REST OF THE
NIGHT. -GIH
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 235 PM SUNDAY...
MONDAY AND MONDAY NIGHT:
BROAD UPPER-LEVEL TROUGH IN PLACE FROM THE GREAT LAKES TO THE LOWER
MS VALLEY WILL GET REINFORCED BY SHORTWAVE TROUGH DIVING SOUTHEAST
ALONG THE SOUTHERN ROCKIES AND INTO THE SOUTHERN PLAINS ON MONDAY.
MEANWHILE...WEAK FRONTAL ZONE AND ASSOCIATED WAVE OF LOW PRESSURE
OVER THE SOUTHERN APPALACHIANS WILL INCH SLOWLY EASTWARD INTO THE
WESTERN CAROLINAS THROUGH MONDAY NIGHT. SHORTWAVE ENERGY IS EXPECTED
TO EJECT EAST-NORTHEASTWARD ACROSS THE AREA IN THE SWLY FLOW ALOFT
DOWNSTREAM OF THE BROAD TROUGH AND WITHIN THE ANOMALOUSLY HIGH (2
STD ABOVE NORMAL)PWAT AIRMASS LYING ALONG AND EAST OF THE WEAK
FRONTAL ZONE ACROSS WESTERN NC. DAYTIME HEATING OF THE MOIST
BOUNDARY LAYER WILL SUPPORT NUMEROUS TO WIDESPREAD SHOWERS/TSTMS
MONDAY AFTERNOON/EVENING...WITH AN AXIS OF MODERATE TO HEAVY RAINFALL
NOT BUDGING VERY MUCH...CENTERED ALONG AND ON THE EASTERN SLOPES OF
THE APPALACHIANS AND POTENTIALLY EXTENDING EAST INTO THE WESTERN
PIEDMONTS OF NC AND VIRGINIA. WHILE THERE REMAINS SOME UNCERTAINTY
WRT TO THE TIMING OF THE EMBEDDED SHORTWAVE IMPULSES...MODEL
CONSENSUS INDICATES THAT THE HEAVY RAINFALL AXIS AND HIGHEST WILL
SHIFT EASTWARD MONDAY NIGHT...REACHING THE COASTAL SECTIONS BY
DAYBREAK TUESDAY.
SEVERE WEATHER THREAT:
WHILE MOIST ADIABATIC PROFILES WILL SUPPORT WEAK MID-LEVEL LAPSE
RATES AND INSOLATION SHOULD BE GREATLY IMPEDED BY WIDESPREAD
CLOUDS...MODELS STILL SUGGEST THE POTENTIAL FOR WEAK TO MODERATE
DESTABILIZATION COULD DEVELOP MONDAY AFTERNOON. UNIDIRECTIONAL SWLY
FLOW OF 25-30 KT COULD SUPPORT A CLUSTER OR TWO OF STRONG TO SEVERE
THUNDERSTORMS THAT COULD PRODUCE DAMAGING WET MICROBURSTS. WITH LOSS
OF DAYTIME HEATING ...THE THREAT OF SEVERE WEATHER SHOULD BE ON THE
WANE MONDAY NIGHT AS THE AIRMASS COOLS/STABILIZES.
HEAVY RAIN THREAT:
WHILE IT WILL GREATLY DEPEND ON HOW MUCH RAINFALL WE SEE THIS
AFTERNOON AND TONIGHT...THE WESTERN PIEDMONT/TRIAD AREA COULD
POTENTIALLY ADD ANOTHER 1 TO 2 INCHES MONDAY AND MONDAY NIGHT TO
WHATEVER WE SEE TONIGHT. 3 HOUR FLASH FLOOD GUIDANCE TODAY FOR THOSE
AREAS ARE AROUND 3.0"...BUT IF WE RECEIVE AN INCH OF RAIN
TONIGHT...IT SHOULD LOWER THE GUIDANCE SIGNIFICANTLY...CLOSE TO THE
TWO INCH THRESHOLD. LATER SHIFTS MAY NEED TO CONSIDER A FLASH FLOOD
WATCH FOR THE WESTERN PIEDMONT MONDAY AFTERNOON/MONDAY NIGHT. EAST
OF THE TRIAD...EXPECT AVERAGE RAINFALL AMOUNTS OF 0.50-1.0"... WITH
ONLY LOCALIZED/URBAN FLOODING EXPECTED.
TEMPERATURES:
HIGHS MONDAY WILL DEPEND ON SHOWER/STORM COVERAGE AND WHETHER WE
WILL MANAGE TO SEE ANY BREAKS IN THE EAST. AFTERNOON HIGHS RANGING
FROM AROUND 70 WEST TO AROUND 80 EAST. LOWS MONDAY NIGHT AGAIN
IN THE 60S. -CBL
TUESDAY AND TUESDAY NIGHT:
ONGOING SHOWERS AND STORMS TUESDAY MORNING SHOULD BE MOVING INTO THE
COASTAL PLAIN AS THE AXIS OF DEEPEST MOISTURE FINALLY SHIFTS TOWARD
THE COAST. HOWEVER...THE WEAK SURFACE FRONT IS FORECAST LINGER BACK
TO THE WEST ALONG THE MOUNTAINS WHILE THE UPPER TROUGH ENERGY
CONTINUES TO EVOLVE WEST OF THE MOUNTAINS....EVENTUALLY PUSHING INTO
THE AREA TUESDAY EVENING. WITH SLIGHTLY DRIER AIR FORECAST TO
OVERSPREAD CENTRAL NC...SOME BREAKS IN CLOUD COVER AND STRONGER
DESTABILIZATION ARE EXPECTED. AHEAD OF THE UPPER TROUGH... THE MAY
CONTINUE TO BE SUBTLE DISTURBANCES ALOFT MOVING ACROSS THE
PERSISTENT WARM AND MOIST AIRMASS...LEADING TO A SCATTERED SHOWERS
AND STORMS BY TUESDAY AFTERNOON. THE NAM IS STRONGEST AND SHOWING A
STOUT VORT MAX LIFTING ACROSS THE AREA DURING PEAK HEATING. A
TIGHTER HEIGHT FIELD ASSOCIATED WITH THIS FEATURE LEADS TO STRONGER
DEEP LAYER SHEAR FORECAST BY THE NAM...BUT THE NAM SEEMS TO BE
OVERDONE. THE GFS AND ECMWF SHOW MORE A MORE DIFFUSE WAVE AND
ONLY 20-25KT OF 0-6KM BULK SHEAR...WHICH IS SUPPORTED BY MOST SREF
MEMBERS. THERE IS CONSIDERABLE SPREAD AMONG SREF MEMBERS REGARDING
INSTABILITY...BUT MODIFIED GFS SOUNDINGS FOR TEMPS IN THE UPPER 70S
TO LOWER 80S AND DEWPOINTS IN THE LOWER 60S SHOW 500-1000 J/KG OF
MLCAPE. A FEW ISOLATED SEVERE STORMS MAY BE POSSIBLE...BUT IF THE
UPPER WAVE IS STRONGER...AS THE NAM FORECASTS...THEN THE SEVERE
POTENTIAL WILL BE GREATER. HIGHS 77-82.
AS THE SURFACE FRONT AND MAIN LOW LEVEL CONVERGENCE ZONE PUSHES INTO
THE CWA TUESDAY EVENING...ISOLATED SHOWERS AND STORMS MAY CONTINUE
INTO THE OVERNIGHT HOURS. THE FRONT WILL CONTINUE TO BE RATHER SLOW
MOVING...AND LOWS SHOULD BE FAIRLY PERSISTENT IN THE UPPER 50S TO
LOWER 60S.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 310 PM SUNDAY...
A SLOW MOVING...WEAK COLD FRONT IS FORECAST TO FINALLY MOVE INTO
CENTRAL NC BY WEDNESDAY MORNING...AS A POSITIVELY TITLED UPPER
TROUGH EXTENDING FROM THE GREAT LAKES INTO THE DEEP SOUTH BEGINS TO
DRIFT EAST ACROSS THE APPALACHIANS MOUNTAINS. DEEP MOISTURE WILL
BEGIN TO TREND DOWNWARD FROM WEST TO EAST AS THE TROUGH MOVES INTO
THE AREA...AND THUS POPS WILL BE INCREASINGLY FOCUSED OVER THE
EASTERN CWA WEDNESDAY AND THURSDAY. TEMPS SHOULD GENERALLY RUN
RIGHT AROUND NORMAL (HIGHS AROUND 80 AND LOWS IN THE MID TO UPPER
50S) IF NOT A SLIGHTLY BELOW NORMAL WITH WEAK TROUGHING ALONG THE
EAST COAST.
THEN...AS ENERGY SWINGING ACROSS THE GREAT LAKES LEAVES
THE SOUTHERN END OF THE UPPER TROUGH BEHIND...MODELS DIVERGE
REGARDING HOW THE TROUGH WILL EVOLVE AS IT DRIFTS EAST TOWARD THE
GA/SC COAST. THE 12Z GFS NEVER QUITE CLOSES OFF AN UPPER LOW AND
ALLOWS THE TROUGH TO BE SWEPT OFF TO THE NORTHEAST AS NORTHERN
STREAM ENERGY SWINGS ACROSS NEW ENGLAND. THE 00Z ECMWF HAD SHOWN A
VERY INTERESTING SOLUTION WITH THE UPPER LOW DEVELOPING ALONG THE
SOUTHEAST COAST AND A POSSIBLE SUBTROPICAL-LIKE LOW THAT DRIFTED
NORTHWEST INTO NC/SC OVER THE WEEKEND. THE 12Z ECMWF RUN SHOWS THE
UPPER LOW FURTHER OFFSHORE AND LITTLE IMPACT OVER NC. THERE IS A
LOT OF SPREAD AMONG GFS AND ECWMF ENSEMBLE MEMBERS...SO CONFIDENCE
IN SENSIBLE WEATHER IMPACTS NEXT WEEKEND IS LOW AT THE MOMENT....BUT
WE WILL KEEP THE FORECAST DRY FOR THIS PACKAGE.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 1205 AM MONDAY...
24-HR TAF PERIOD:
DETERIORATING CONDITIONS ARE EXPECTED THIS MORNING...WITH LITTLE (IF
ANY) IMPROVEMENT THROUGH THE REMAINDER OF THE TAF PERIOD. AN UPPER
LEVEL TROUGH AND ASSOCIATED SURFACE LOW PRESSURE SYSTEM WILL
CONTINUE TO SLOWLY APPROACH THE CAROLINAS FROM THE WEST TODAY AND
TONIGHT. PERIODS OF SHOWERS ARE EXPECTED THIS MORNING...WITH
CEILINGS LOWERING TO IFR/LIFR AT THE INT/GSO TERMINALS AND MVFR/IFR
AT THE RDU/FAY/RWI TERMINALS. PERIODS OF SHOWERS AND THUNDERSTORMS
ARE EXPECTED THIS AFTERNOON...WITH ONLY A MARGINAL IMPROVEMENT IN
CEILINGS DURING PEAK HEATING. EXPECT CEILINGS AND VISBYS TO DECREASE
INTO THE IFR/LIFR RANGE EVERYWHERE BETWEEN SUNSET THIS EVENING AND
SUNRISE TUE MORNING. SE/SSE WINDS AT ~5 KT WILL PERSIST THROUGH
SUNRISE...WITH SE/SSE WINDS INCREASING TO ~10 KT BY THIS AFTERNOON.
LOOKING AHEAD:
LINGERING LOW-LEVEL MOISTURE COMBINED WITH ANOTHER UPPER LEVEL
TROUGH APPROACHING THE AREA FROM THE NORTHWEST WILL ALLOW ADVERSE
AVIATION CONDITIONS TO PERSIST TUE/TUE NIGHT...WITH SCATTERED
SHOWERS AND THUNDERSTORMS POSSIBLE AT ALL TERMINALS. IMPROVING
CONDITIONS ARE EXPECTED WED/WED NIGHT AS THE UPPER LEVEL TROUGH AND
ASSOCIATED SURFACE LOW PROGRESS CLOSER TOWARD THE SOUTHEAST COAST...
THOUGH MVFR CONDITIONS APPEAR LIKELY IN MANY LOCATIONS. UNCERTAINTY
INCREASES TOWARD THE LATTER PORTION OF THE WEEK. AT THIS TIME...
VFR/MVFR CEILINGS (2500-4500 FT AGL) ARE EXPECTED THU/FRI. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...HARTFIELD
SHORT TERM...CBL/BLS
LONG TERM...BLS
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
1229 PM CDT MON MAY 14 2012
.DISCUSSION...SEE AVIATION SECTION BELOW.
&&
.AVIATION...CLOUDS AROUND 15K FT ARE MOVG ACROSS S TX WITH A LOWER
DECK DVLPG AROUND 4K FT. EXPECTING VFR CONDITIONS THROUGH THE
REMAINDER OF THE DAY AND INTO THE EVENING HOURS. AN UPPER
DISTURBANCE WILL BRING SHRA`S/TSRA`S FROM THE BIG BEND AREA DOWN
INTO THE RIO GRANDE PLAINS TONIGHT AND ACROSS S TX OVERNIGHT AND
INTO TUE. MVFR/IFR CONDITIONS ARE EXPECTED IN AND AROUND THE
PRECIP LATE TONIGHT INTO TUE.
&&
.PREV DISCUSSION... /ISSUED 946 AM CDT MON MAY 14 2012/
DISCUSSION...THE REMAINS OF AN MCS IS WEAKENING AS IT MOVES
SOUTHEAST ACROSS THE WESTERN CWA. MOST MODELS DID NOT EVEN PICK UP
ON THIS PRECIP...HOWEVER THE LATEST RUC13 HAS AND IT SHOWS THE
PRECIP DISSIPATING OVER THE NEXT COUPLE OF HOURS...MAINLY DUE TO A
SLIGHTLY SUBSIDENT/DRIER AIRMASS IN PLACE ACROSS THE E CWA. ONLY
CONCERN IS THAT THIS PRECIP IS HEADING TOWARD AN AREA OF LESS
CIN/HIGHER CAPE ACROSS THE E CWA. FOR NOW...WILL LEAVE POPS AS
IS FOR TODAY UNLESS THIS SYSTEM RE-INTENSIFIES. REST OF FCST LOOKS
ON TRACK. NO MAJOR CHANGES TO THE FCST AT THIS TIME.
PREV DISCUSSION... /ISSUED 724 AM CDT MON MAY 14 2012/
DISCUSSION...INTRODUCED SLIGHT END POPS UNTIL 18Z ACROSS THE RIO
GRANDE PLAINS AS MCS CONTINUES TO MOVE SOUTHEAST THIS MORNING.
UPDATED PRODUCTS OUT.
PREV DISCUSSION... /ISSUED 659 AM CDT MON MAY 14 2012/
DISCUSSION...UPDATED FOR 12Z AVIATION
AVIATION...LINGERING CONVECTION OVER MAVERICK COUNTY SHOULD
CONTINUE TO MOVE EAST...BUT SHOULD NOT IMPACTING THE TERMINALS.
OTHERWISE...VFR CONDITIONS TO PERSIST THROUGH TODAY. UPPER LEVEL
DISTURBANCE AND CHANCES FOR CONVECTION WILL INCREASE TONIGHT FROM
THE NORTHWEST. INCLUDED VCTS REMARKS AT LRD IN ANTICIPATION OF MCS
DEVELOPING TONIGHT. DID NOT INCLUDE AT THE OTHER TERMINALS ATTM.
WINDS GENERALLY REMAIN LESS THAN 12 KNOTS AT ALI/CRP/VCT...BUT MAY
BECOME A LITTLE GUSTY IN THE AFTERNOON AT LRD.
PREV DISCUSSION... /ISSUED 409 AM CDT MON MAY 14 2012/
SHORT TERM (TODAY THROUGH TUESDAY)...LATEST RADAR TRENDS SHOW
WEAKENING MCS OVER THE BIG BEND OF TEXAS. ANTICIPATE THIS
CONVECTION WILL NOT MAKE IT INTO LA SALLE AND WEBB COUNTIES SO
WILL KEEP POPS SILENT FOR THE MORNING HOURS. UPPER LEVEL TROUGH
WILL DROP SOUTHEAST OUT OF NEW MEXICO TODAY AND TONIGHT. MOISTURE
FIELDS BEGIN TO INCREASE BY THIS EVENING. HIGH RESOLUTION MODELS
DEVELOP ANOTHER MCS OVER THE BIG BEND TONIGHT WITH IT TRACKING
FURTHER TO THE SOUTHEAST...APPROACHING THE NORTHWESTERN ZONES
BETWEEN 03Z AND 06Z TUESDAY. IF STORMS ARE ABLE TO MAINTAIN THEIR
STRENGTH...THEN PERHAPS A DAMAGING WIND GUST THREAT COULD
EMERGE...BUT CONFIDENCE OF THIS OCCURRING IS ON THE LOW SIDE. WENT
AHEAD AND INCREASED POPS ACROSS LA SALLE AND WEBB COUNTIES TO 60
PERCENT...TAPERING OFF TO 20 PERCENT OVER THE COASTAL WATERS FOR
THE TONIGHT PERIOD. HIGHER RAINFALL AMOUNTS SHOULD OCCUR NORTH OF
THE AREA. UPPER TROUGH WEAKEN A BIT AS IT CONTINUES TO MOVE TO THE
SOUTHEAST ON TUESDAY. NAM/GFS IN DECENT AGREEMENT ON PRECIP CHANCES
AND HAVE RAISED THEM A LITTLE. CLOUD COVER AND CHANCES FOR PRECIP
WILL KEEPS TEMPS DOWN ON TUESDAY... MAINLY IN THE LOWER 80S.
FAVORED THE COOLER METMOS TEMPS.
LONG TERM (TUESDAY NIGHT THROUGH SUNDAY)...ANY PRECIP THAT EXISTS
AT START OF LONG TERM PERIOD SHOULD END FROM NORTH TO SOUTH AS UPPER
LEVEL TROUGH AXIS SWINGS SOUTH OF CWA AND SURFACE HIGH PRESSURE
BUILDS INTO AREA. 00Z ECMWF IS ABOUT SIX HRS SLOWER THAN GFS WITH
MOVEMENT OF SYSTEM AND A LINGERING CHANCE OF PRECIP MAY BE NEEDED IN
LATER FORECAST PKGS IF SYSTEM SLOWS...BUT FOR NOW WILL LEAVE WED
DRY. QUIET WX THEN EXPECTED FOR SECOND HALF OF WORK WEEK AS WEAK
MID/UPPER LEVEL RIDGING DEVELOPS RESULTING IN WNW FLOW ALOFT AND
LIMITED DEEP LAYER MOISTURE. BY NEXT WEEKEND GFS AND ECMWF DIFFER
SOMEWHAT WITH MID/UPPER LEVEL PATTERN. GFS HAS MORE ZONAL FLOW WITH
ELONGATED MID LEVEL RIDGING WHILE ECMWF HAS MORE PRONOUNCED S/W
TROUGHS MOVING ACROSS THE PLAINS. BOTH GUIDANCE SUITES INITIATE
SURFACE CYCLOGENESIS ACROSS THE NORTHERN SOUTH HIGH PLAINS AND
DIURNAL SFC TROUGHING WHICH IN TURN SHOULD TIGHTEN THE PRESSURE
GRADIENT ACROSS S TX AND ALLOW LOW LEVEL MOISTURE ADVECTION TO
INCREASE. LOW LEVEL MOISTURE VALUES AND WIND PROFILE MAY BECOME MORE
CONDUCIVE FOR ISOLATED STREAMER SHOWERS ACROSS MARINE ZONES AND
COASTAL PLAINS BY LATE IN THE EXTENDED PERIOD. TEMPS ARE EXPECTED TO
BE AT OR SLIGHTLY ABOVE SEASONABLE VALUES /EXCEPT AROUND MID WEEK
WHERE BELOW NORMAL MIN TEMPS MAY OCCUR WHEN HIGH PRESSURE CENTER IS
THE CLOSEST/ AND HAVE GENERALLY GONE CLOSE TO A BIAS CORRECTED
MOSGUIDE/ECMWF BLEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 86 68 82 64 86 / 10 30 50 20 10
VICTORIA 86 64 80 60 86 / 10 30 50 20 10
LAREDO 92 69 86 67 91 / 20 50 50 20 10
ALICE 89 66 84 61 88 / 10 30 50 20 10
ROCKPORT 86 71 80 68 86 / 10 30 50 20 10
COTULLA 88 64 82 60 89 / 20 60 50 10 10
KINGSVILLE 88 68 84 62 87 / 10 30 50 30 10
NAVY CORPUS 84 71 82 68 84 / 10 30 50 30 10
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
TE/81...SHORT TERM
GW/86...LONG TERM
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
946 AM CDT MON MAY 14 2012
.DISCUSSION...THE REMAINS OF AN MCS IS WEAKENING AS IT MOVES
SOUTHEAST ACROSS THE WESTERN CWA. MOST MODELS DID NOT EVEN PICK UP
ON THIS PRECIP...HOWEVER THE LATEST RUC13 HAS AND IT SHOWS THE
PRECIP DISSIPATING OVER THE NEXT COUPLE OF HOURS...MAINLY DUE TO A
SLIGHTLY SUBSIDENT/DRIER AIRMASS IN PLACE ACROSS THE E CWA. ONLY
CONCERN IS THAT THIS PRECIP IS HEADING TOWARD AN AREA OF LESS
CIN/HIGHER CAPE ACROSS THE E CWA. FOR NOW...WILL LEAVE POPS AS
IS FOR TODAY UNLESS THIS SYSTEM RE-INTENSIFIES. REST OF FCST LOOKS
ON TRACK. NO MAJOR CHANGES TO THE FCST AT THIS TIME.
&&
.PREV DISCUSSION... /ISSUED 724 AM CDT MON MAY 14 2012/
DISCUSSION...INTRODUCED SLIGHT END POPS UNTIL 18Z ACROSS THE RIO
GRANDE PLAINS AS MCS CONTINUES TO MOVE SOUTHEAST THIS MORNING.
UPDATED PRODUCTS OUT.
PREV DISCUSSION... /ISSUED 659 AM CDT MON MAY 14 2012/
DISCUSSION...UPDATED FOR 12Z AVIATION
AVIATION...LINGERING CONVECTION OVER MAVERICK COUNTY SHOULD
CONTINUE TO MOVE EAST...BUT SHOULD NOT IMPACTING THE TERMINALS.
OTHERWISE...VFR CONDITIONS TO PERSIST THROUGH TODAY. UPPER LEVEL
DISTURBANCE AND CHANCES FOR CONVECTION WILL INCREASE TONIGHT FROM
THE NORTHWEST. INCLUDED VCTS REMARKS AT LRD IN ANTICIPATION OF MCS
DEVELOPING TONIGHT. DID NOT INCLUDE AT THE OTHER TERMINALS ATTM.
WINDS GENERALLY REMAIN LESS THAN 12 KNOTS AT ALI/CRP/VCT...BUT MAY
BECOME A LITTLE GUSTY IN THE AFTERNOON AT LRD.
PREV DISCUSSION... /ISSUED 409 AM CDT MON MAY 14 2012/
SHORT TERM (TODAY THROUGH TUESDAY)...LATEST RADAR TRENDS SHOW
WEAKENING MCS OVER THE BIG BEND OF TEXAS. ANTICIPATE THIS
CONVECTION WILL NOT MAKE IT INTO LA SALLE AND WEBB COUNTIES SO
WILL KEEP POPS SILENT FOR THE MORNING HOURS. UPPER LEVEL TROUGH
WILL DROP SOUTHEAST OUT OF NEW MEXICO TODAY AND TONIGHT. MOISTURE
FIELDS BEGIN TO INCREASE BY THIS EVENING. HIGH RESOLUTION MODELS
DEVELOP ANOTHER MCS OVER THE BIG BEND TONIGHT WITH IT TRACKING
FURTHER TO THE SOUTHEAST...APPROACHING THE NORTHWESTERN ZONES
BETWEEN 03Z AND 06Z TUESDAY. IF STORMS ARE ABLE TO MAINTAIN THEIR
STRENGTH...THEN PERHAPS A DAMAGING WIND GUST THREAT COULD
EMERGE...BUT CONFIDENCE OF THIS OCCURRING IS ON THE LOW SIDE. WENT
AHEAD AND INCREASED POPS ACROSS LA SALLE AND WEBB COUNTIES TO 60
PERCENT...TAPERING OFF TO 20 PERCENT OVER THE COASTAL WATERS FOR
THE TONIGHT PERIOD. HIGHER RAINFALL AMOUNTS SHOULD OCCUR NORTH OF
THE AREA. UPPER TROUGH WEAKEN A BIT AS IT CONTINUES TO MOVE TO THE
SOUTHEAST ON TUESDAY. NAM/GFS IN DECENT AGREEMENT ON PRECIP CHANCES
AND HAVE RAISED THEM A LITTLE. CLOUD COVER AND CHANCES FOR PRECIP
WILL KEEPS TEMPS DOWN ON TUESDAY... MAINLY IN THE LOWER 80S.
FAVORED THE COOLER METMOS TEMPS.
LONG TERM (TUESDAY NIGHT THROUGH SUNDAY)...ANY PRECIP THAT EXISTS
AT START OF LONG TERM PERIOD SHOULD END FROM NORTH TO SOUTH AS UPPER
LEVEL TROUGH AXIS SWINGS SOUTH OF CWA AND SURFACE HIGH PRESSURE
BUILDS INTO AREA. 00Z ECMWF IS ABOUT SIX HRS SLOWER THAN GFS WITH
MOVEMENT OF SYSTEM AND A LINGERING CHANCE OF PRECIP MAY BE NEEDED IN
LATER FORECAST PKGS IF SYSTEM SLOWS...BUT FOR NOW WILL LEAVE WED
DRY. QUIET WX THEN EXPECTED FOR SECOND HALF OF WORK WEEK AS WEAK
MID/UPPER LEVEL RIDGING DEVELOPS RESULTING IN WNW FLOW ALOFT AND
LIMITED DEEP LAYER MOISTURE. BY NEXT WEEKEND GFS AND ECMWF DIFFER
SOMEWHAT WITH MID/UPPER LEVEL PATTERN. GFS HAS MORE ZONAL FLOW WITH
ELONGATED MID LEVEL RIDGING WHILE ECMWF HAS MORE PRONOUNCED S/W
TROUGHS MOVING ACROSS THE PLAINS. BOTH GUIDANCE SUITES INITIATE
SURFACE CYCLOGENESIS ACROSS THE NORTHERN SOUTH HIGH PLAINS AND
DIURNAL SFC TROUGHING WHICH IN TURN SHOULD TIGHTEN THE PRESSURE
GRADIENT ACROSS S TX AND ALLOW LOW LEVEL MOISTURE ADVECTION TO
INCREASE. LOW LEVEL MOISTURE VALUES AND WIND PROFILE MAY BECOME MORE
CONDUCIVE FOR ISOLATED STREAMER SHOWERS ACROSS MARINE ZONES AND
COASTAL PLAINS BY LATE IN THE EXTENDED PERIOD. TEMPS ARE EXPECTED TO
BE AT OR SLIGHTLY ABOVE SEASONABLE VALUES /EXCEPT AROUND MID WEEK
WHERE BELOW NORMAL MIN TEMPS MAY OCCUR WHEN HIGH PRESSURE CENTER IS
THE CLOSEST/ AND HAVE GENERALLY GONE CLOSE TO A BIAS CORRECTED
MOSGUIDE/ECMWF BLEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 86 68 82 64 86 / 10 30 50 20 10
VICTORIA 86 64 80 60 86 / 10 30 50 20 10
LAREDO 92 69 86 67 91 / 20 50 50 20 10
ALICE 89 66 84 61 88 / 10 30 50 20 10
ROCKPORT 86 71 80 68 86 / 10 30 50 20 10
COTULLA 88 64 82 60 89 / 20 60 50 10 10
KINGSVILLE 88 68 84 62 87 / 10 30 50 30 10
NAVY CORPUS 84 71 82 68 84 / 10 30 50 30 10
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
TE/81...SHORT TERM
GW/86...LONG TERM
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
1155 PM CDT SUN MAY 13 2012
.AVIATION...
FOR THE 06Z TAFS...ONGOING SHOWERS AND THUNDERSTORMS WERE NORTH AND
WEST OF THE TERMINALS AND ARE EXPECTED TO STAY OUTSIDE OF THE
VICINITY OF THE TERMINALS OVERNIGHT. HOWEVER ANOTHER ROUND OF
SHOWERS CAN IMPACT THE KAMA/KDHT TERMINALS BY 11-12Z WHILE THINK
SHOWERS WILL NOT AFFECT THE KGUY TERMINAL. HAVE KEPT CONDITIONS VFR
THROUGH THE FORECAST PERIOD ALTHOUGH MODERATE TO HEAVY RAINFALL CAN
BRIEFLY REDUCE VISBYS TO MVFR. AS THE UPPER-LEVEL TROUGH MOVES INTO
WEST TX ON MONDAY...SKIES SHOULD BEGIN TO DIMINISH WITH ONLY FEW TO
SCT MID CLOUDS BY 20-00Z.
CLK
&&
.PREV DISCUSSION... /ISSUED 655 PM CDT SUN MAY 13 2012/
AVIATION...
FOR THE 00Z TAFS...ONGOING SHOWERS AND THUNDERSTORMS CONTINUE TO
IMPACT THE KAMA TERMINAL WHERE MODERATE TO HEAVY RAIN HAS REDUCED
VISBYS DOWN TO BELOW 2 MILES BRIEFLY. CURRENT RADAR IMAGERY SHOWS
STORMS SLOWLY MOVING EAST...SO EXPECT TSRA TO IMPACT KAMA THROUGH
01Z. HAVE INSERTED A TEMPO GROUP WITH MVFR VISBYS AT 2SM THROUGH THEN
AS ADDITIONAL HEAVY RAINFALL CAN ACCOMPANY THESE STORMS. KDHT IS
CURRENTLY REPORTING MVFR VISBYS IN LIGHT FOG WHICH SHOULD CONTINUE
THIS EVENING. STORMS CONTINUE TO DEVELOP ACROSS THE EASTERN PLAINS
0F CO/NM AS UPPER LIFT PROVIDED BY AN UPPER SHORTWAVE TROUGH IN THE
FOUR CORNERS AREA COMBINES WITH MOIST LOW-LEVEL UPSLOPE FLOW. HAVE
CARRIED -SHRA TONIGHT AT THE TERMINALS AS THESE SHOWERS WILL
CONTINUE TO MOVE TO THE EAST. OUTSIDE OF ANY STRONGER SHOWER THAT MAY
PRODUCE MODERATE OR HEAVY RAINFALL THAT CAN REDUCE BRIEFLY REDUCE
VISBYS...EXPECT VFR CONDITIONS THROUGH THE TAF FORECAST PERIOD. THE
UPPER SHORTWAVE TROUGH IS EXPECTED TO CONTINUE TO DROP SOUTH AND MOVE
INTO WEST TX BY MONDAY AFTERNOON. THUS EXPECT -SHRA MONDAY MORNING
AND AFTERNOON WITH SKIES THINNING TOWARD THE END OF THE FORECAST
PERIOD...PARTICULARLY AT KGUY/KDHT.
CLK
PREV DISCUSSION... /ISSUED 332 PM CDT SUN MAY 13 2012/
DISCUSSION...
PRIMARY FOCUS IS ON PRECIPITATION CHANCES THROUGH MONDAY.
AFTERNOON WATER VAPOR IMAGERY SHOWED A MID/UPPER-LEVEL SHORTWAVE
TROUGH SINKING SOUTHEAST ACROSS EASTERN UT TOWARDS THE FOUR CORNERS
REGION. MID TO UPPER-LEVEL FORCING AHEAD OF THIS SHORTWAVE HAS
COMBINED WITH DAYTIME HEATING/DESTABILIZATION AND LOW-LEVEL UPSLOPE
FLOW OVER EASTERN CO AND NM TO GENERATE SHOWERS AND THUNDERSTORMS.
THE GREATEST CONVECTIVE COVERAGE IS CURRENTLY ACROSS NORTHEAST NM
WORKING INTO THE SOUTHWEST TX PANHANDLE...BUT ADDITIONAL SCATTERED
SHOWERS AND THUNDERSTORMS HAVE DEVELOPED FARTHER EAST ACROSS THE
PANHANDLES DUE TO THE COMBINATION OF AFTERNOON DESTABILIZATION AND
BROADER SCALE LIFT AHEAD OF THE SHORTWAVE.
SHOWERS AND THUNDERSTORMS WILL CONTINUE TO IMPACT THE AREA THIS
EVENING AND OVERNIGHT. THE MID/UPPER-LEVEL SHORTWAVE TROUGH WILL
CONTINUE TO DIVE SOUTHEAST...REACHING NORTHERN/CENTRAL NM BY EARLY
MONDAY MORNING. DIFFLUENT/DIVERGENT FLOW ALOFT AHEAD OF THIS WAVE
WILL CONTINUE TO SUPPORT CONVECTION PROPAGATING EAST/SOUTHEAST OUT OF
NM AND CO THIS EVENING AND OVERNIGHT. BEST DYNAMICS WILL BE FOCUSED
ACROSS THE SOUTHWEST HALF OF THE AREA AND HAVE ALIGNED POPS
ACCORDINGLY. ALSO SOME WEAK ISENTROPIC LIFT EVIDENT ON THE 305K THETA
SURFACE ACROSS THE SOUTHWEST TX PANHANDLE THIS EVENING TO FURTHER AID
CONVECTION. LATEST LAPS AND RUC ANALYSIS DATA SHOW MLCAPES IN THE
500-1000 J/KG RANGE ACROSS THE WESTERN PANHANDLES WITH LESSER VALUES
TO THE EAST AND DEEP LAYER SHEAR AROUND 30-35 KTS IN THE SOUTHWEST
TX PANHANDLE...DECREASING TO THE NORTHEAST. THUS COULD SEE A FEW
STRONG STORMS THROUGH THIS EVENING CAPABLE OF PRODUCING SMALL HAIL
AND GUSTY WINDS...BUT NOT REALLY ANTICIPATING ANY SEVERE WEATHER
/ALTHOUGH AN ISOLATED MARGINALLY SEVERE STORM ACROSS THE SOUTHWEST CAN/T
BE RULED OUT/. COULD ALSO SEE SOME LOCALLY HEAVY RAIN GIVEN PWATS IN
THE THREE QUARTERS OF AN INCH TO ONE INCH RANGE AND SOME TRAINING OF
STORMS POSSIBLE. BETTER RAIN CHANCES LOOK TO GRADUALLY SHIFT
SOUTH/SOUTHWEST OF THE AREA LATE TONIGHT IN ASSOCIATION WITH STRONGER
DIVERGENCE ALOFT...AND ALSO AS THE LLJ AND LOW-LEVEL ISENTROPIC LIFT
FOCUS TO OUR SOUTHWEST.
RAIN CHANCES LINGER INTO MONDAY...BUT WILL GRADUALLY END FROM NORTH
TO SOUTH THROUGH THE DAY AS THE SHORTWAVE CONTINUES TO DIVE SOUTHEAST
TO SOUTHEAST NM/SOUTHWEST TX BY EARLY MONDAY EVENING. BETTER RAIN
CHANCES WILL BE FOCUSED ACROSS THE SOUTHERN HALF OF THE CWA ON
MONDAY. WEAKER INSTABILITY AND SHEAR SHOULD PRECLUDE ANY STRONG OR
SEVERE STORMS. WILL ALSO SEE THE COOLEST TEMPS IN THE SOUTH ON MONDAY
DUE TO LINGERING CLOUDS/PRECIP...WITH HIGHS FORECAST TO RANGE FROM
THE UPPER 60S SOUTHWEST TO MID/UPPER 70S NORTH.
DRY CONDITIONS ARE THEN FORECAST BEGINNING MONDAY NIGHT AS SHORTWAVE
UPPER RIDGING BUILDS EAST ACROSS THE SOUTHERN AND CENTRAL ROCKIES.
TEMPS WILL BEGIN TO REBOUND ON TUESDAY DUE TO RISING HEIGHTS...A
RETURN OF WEAK SOUTHERLY WINDS...AND INCREASED SUNSHINE...WITH HIGHS
CLIMBING BACK INTO THE UPPER 70S TO LOWER 80S. A DAMPENING MID-LEVEL
SHORTWAVE WILL WORK ACROSS THE CENTRAL ROCKIES AND PLAINS WEDNESDAY
AND WEDNESDAY NIGHT. THIS COULD POTENTIALLY SPAWN A FEW
SHOWERS/THUNDERSTORMS ACROSS THE NORTHERN PANHANDLES WEDNESDAY NIGHT.
HOWEVER...CHANCES LOOK LOW AT THIS TIME AS BETTER DYNAMICS WILL STAY
TO OUR NORTH AND COME ACROSS AT NIGHT...BY WHICH TIME ELEVATED
INSTABILITY LOOKS MINIMAL. THUS KEPT A DRY FORECAST FOR NOW. THE LEE
TROUGH WILL DEEPEN ON WEDNESDAY...WITH RESULTANT BREEZY SOUTHWEST
WINDS FURTHER CONTRIBUTING TO THE WARM UP.
A ZONAL FLOW/BROAD FLAT RIDGING LATE THIS WEAK WILL TRANSITION TO
SOUTHWESTERLY OVER THE WEEKEND AS AN UPPER TROUGH WORKS ACROSS THE
INTERMOUNTAIN WEST AND ROCKIES EVENTUALLY INTO THE NORTHERN PLAINS.
THIS FLOW ALOFT WILL PROMOTE SURFACE LEE TROUGHING AND SOME
SHARPENING OF THE DRYLINE BY FRIDAY AND SATURDAY. HOWEVER IT
CURRENTLY LOOKS LIKE WARM TEMPS ALOFT AND A LACK OF UPPER FORCING /AS
THE TROUGH IS DEFLECTED WELL TO OUR NORTHWEST/ WILL MAKE IT TOUGH FOR
CONVECTION TO INITIATE. THUS WILL MAINTAIN A DRY FORECAST. ABOVE
NORMAL TEMPERATURES EXPECTED LATE WEEK INTO THE WEEKEND WITH HIGHS IN
THE MID 80S TO LOWER 90S. WILL HAVE TO KEEP AN EYE ON A POTENTIAL
COLD FRONT THAT MAY MOVE IN SUNDAY OR SUNDAY NIGHT.
KB
FIRE WEATHER...
NO ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ARE CURRENTLY
EXPECTED THROUGH THE WEEK. SOUTH/SOUTHWEST WINDS WILL INCREASE TO 15
TO 20 MPH ON WEDNESDAY AND RELATIVE HUMIDITIES MAY FALL TO 15 TO 20
PERCENT ACROSS THE FAR WESTERN PANHANDLES...BUT RECENT RAINFALL AND
RESULTANT GREEN-UP SHOULD MITIGATE ANY FIRE WEATHER CONCERNS. WARMER
TEMPERATURES WILL CONTINUE LATE WEEK INTO THE WEEKEND AND MINIMUM
RELATIVE HUMIDITIES WILL FALL TO 15 TO 20 PERCENT ACROSS WESTERN
AREAS. SOUTH/SOUTHWEST WINDS WILL BE BREEZY AT TIMES AND ELEVATED
FIRE WEATHER CONDITIONS COULD DEVELOP...BUT AGAIN RECENT RAINFALL AND
GREEN-UP WILL HELP MINIMIZE FIRE WEATHER CONCERNS.
KB
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
05/15
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1052 PM EDT TUE MAY 15 2012
.SYNOPSIS...
THE PESKY WEAK STATIONARY BOUNDARY...WHICH HAS BEEN THE FOCUS FOR
HEAVY RAINFALL THE PAST FEW DAYS...WILL FINALLY DRIFT EAST TONIGHT
THROUGH WEDNESDAY. HIGH PRESSURE WILL DRIFT ACROSS THE UPPER OHIO
VALLEY ON THURSDAY...THEN MOVE OFF THE NEW ENGLAND COAST BY
SUNDAY...IN RESPONSE TO A STRENGTHENING UPPER RIDGE.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
AS OF 1035 PM EDT TUESDAY...
PLANNING TO GO AHEAD AND DROP THE FLASH FLOOD WATCH OVERNIGHT
GIVEN LACK OF COVERAGE AND NOCTURNAL COOLING. HOWEVER SOME
GUIDANCE INCLUDING THE HRRR STILL WANTS TO REDEVELOP HEAVIER SHRA
ESPCLY SOUTH AFTER MIDNIGHT ALONG WHERE THE CURRENT THETA-E
GRADIENT EXISTS. THINK THIS IS OVERDONE AT THIS POINT BUT APPEARS SOME
SHRA WILL FILL BACK IN ALONG THE FOOTHILLS GIVEN LEFTOVER
INSTABILITY BUT LIKELY TOO ISOLATED TO KEEP A BROAD WATCH UP AT
THIS POINT. THUS WILL ONLY KEEP IN HIGH CHANCE POPS SOUTH/EAST
OVERNIGHT WITH MENTION OF BRIEF HEAVY RAIN IN THE HWO. DRIER AIR
SEEPING INTO THE WEST SHOULD KEEP THINGS DRY FROM THE NEW RIVER
VALLEY NORTH AND WEST OVERNIGHT SO TRIMMED POPS A BIT MORE THERE
WITH ADDITION OF MORE DENSE FOG IN SPOTS ESPCLY WHERE ADDED HEAVY
RAINFALL OCCURRED THIS EVENING. MAY NEED A DENSE FOG ADVISORY BY
MORNING AS WELL MAINLY SOUTH AND EAST WHERE DEWPOINTS ARE HIGHER
AND DRIER AIR WONT MAKE IT UNTIL EARLY WED AT BEST. NUDGED DOWN LOW
TEMPS A FEW DEGREES WEST OTRW STAYED CLOSE TO THE PREVIOUS
FORECAST.
AS OF 8 PM EDT TUESDAY...
SENT A QUICK UPDATE TO LOWER POPS SIGNIFICANTLY ACROSS THE AREA
GIVEN DIMINISHING ECHOES ALONG THE BLUE RIDGE AND ONLY SCTD STORMS
REMAINING IN THE PIEDMONT AND WEST OF THE NC NRN MOUNTAINS.
APPEARS A BIT LOWER THETA-E AIR ACROSS THE FAR WEST HAS WEAKENED
THE ONGOING CONVERGENCE...WITH OUTFLOW DRIVEN STORMS ACROSS THE
EAST. HOWEVER INSTABILITY REMAINS PRETTY HIGH ESPCLY SOUTH-SE SO
LEAVING IN HIGH CHANCE FOR A FEW MORE HOURS BEFORE LIKELY SEEING A
MORE DIURNALLY DRIVEN REDUCTION IN COVERAGE THIS EVENING PER
WEAKER SUPPORT AND MORE WEST/SW FLOW ALOFT ATTM. APPEARS MOST
AREAS MAY BE PRECIP FREE AROUND MIDNIGHT IF NOT SOONER SIMILAR TO
TO PREVIOUS THINKING SO KEPT IN A SMALL POP MAINLY SE THIRD
OVERNIGHT. MAY ALSO BE ABLE TO DROP THE WATCH EARLY PENDING
COVERAGE OVER THE NEXT COUPLE OF HOURS.
AS OF 249 PM EDT TUESDAY...
SIMILAR TO YESTERDAY AT THIS TIME...SHOWERS AND STORMS HAVE BEEN
SLOW TO DEVELOP THANKS TO CLOUD COVER. BUT WOULDN`T BE SURPRISED
IF RAPID DEVELOPMENT AGAIN OCCURS BY LATE AFTERNOON...WITH OUTFLOW
BOUNDARIES ONLY HELPING MORE STORMS TO POP UP. SPC MESOANALYSIS
CONTINUES TO SHOW INCREASING CAPE/INSTABILITY DESPITE THE CLOUD
COVER. THUNDERSTORMS ALREADY BEGINNING TO LINE UP FROM SW TO NE IN
GRAYSON COUNTY...AND AS THIS CLUSTER MOVES NE MAY BE THE BEGINNING
OF MORE ORGANIZATION MOVING TOWARDS FLOYD AND HARD HIT FRANKLIN
COUNTY. BY DINNERTIME...LOCAL MODELS HAVE AN ORGANIZED TRAINING LINE
RIGHT ALONG THE BLUE RIDGE...AND THE CELLS MAY STAY ANCHORED TO
THE MOUNTAINS CONSIDERING MEAGER LLVL WIND FIELDS AND NIL
SHEAR...BELOW 10 M/S...EVEN THROUGH 3KM AGL. THUS...THE FLASH FLOOD
WATCH STANDS. DESPITE THE RATHER WET SOUNDING...ENOUGH MIDLEVEL
DRY AIR EXISTS SUCH THAT 500 J/KG OF DCAPE IS PRESENT...SO SOME
GUSTY WINDS AND SCATTERED SVR STORMS ARE ALSO POSSIBLE...PER SPC
SLT RISK IN OUR AREA. OF COURSE VERY LOW FFG ESPECIALLY IN HARD
HIT FRANKLIN AND ROCKBRIDGE...UNDER AN INCH AN HOUR...SO IT WILL
NOT TAKE MUCH FOR MORE WATER PROBLEMS CONSIDERING PWATS 120% OF
NORMAL. AGAIN COULD BE LOOKING AT A CRITICAL SITUATION ACROSS THE
HARD HIT AREAS CONSIDERING THESE STORMS HAVE THE POTENTIAL TO PUT
DOWN AN INCH OR TWO IN 30 MINUTES. THE FLASH FLOOD WATCH MAY HAVE
TO BE EXPANDED TOO DEPENDING UPON DEVELOPMENT. LOOKING FOR
FOG WHICH AGAIN COULD BE DENSE AFTER MIDNIGHT...AS STORMS FINALLY
DIE.
WITH THE WEAK BOUNDARY FINALLY MAKING SOME EASTWARD PROGRESS
WEDNESDAY...LLVL WINDS WILL BE DEEPER AND STRONGER FROM A
DOWNSLOPING DIRECTION AS FAR EAST AS THE BLUE RIDGE. ALTHOUGH THIS
USUALLY CREATES ENOUGH SUBSIDENCE TO PRECLUDE PRECIP...CAN`T RULE
OUT AN ISOLATED THUNDERSTORMS OUTSIDE OF SE WEST VA CONSIDERING
SOME INSTABILITY STILL IN PLACE AND DEVELOPING WEAK LEE TROUGH.
LIMITING FACTOR THOUGH WILL BE MIDLEVEL MOISTURE...AS H7 RH GETS
PRETTY DRY BY 18Z/2P WEDNESDAY NEW RIVER VALLEY AND WEST. BEST
OPPORTUNITY FOR SCATTERED STORMS WILL BE ALONG THE SOUTHSIDE
WEDNESDAY...WHERE SOME STORMS AGAIN COULD BE SEVERE...WITH
SOMEWHAT BETTER SHEAR AND UPPER LEVEL WINDS AS A FEW DISTURBANCES
RIDE NE TOWARDS RDU. DRIER AIR AND DOWNSLOPE WARMING...WITH LESS
CLOUDS COMBINED WITH H85 TEMPS AROUND +14C...MEAN THE WARMER SPOTS
SHOULD CROSS 80F SO MAX T WAS RAISED BY SEVERAL DEGREES TO PUT IT
MORE IN LINE WITH MAV/MET MOS.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
AS OF 300 PM EDT TUESDAY...
KEEPING JUST A SLIGHT CHANCE OF SHOWERS/TSRA IN THE FAR SOUTHEAST
WED EVENING AS THE FRONT DEPARTS. WILL SEE CLEARING SKIES WITH WINDS
OUT OF NW AND LIGHT. NOT OUT OF THE QUESTION TO SEE SOME FOG LATE
WED NIGHT IN THE DEEPER VALLEYS.
AMPLIFICATION OF THE 5H TROUGH TAKES PLACE OVER THE SOUTHEAST WITH
MODELS CLOSING OFF A LOW OFF THE COAST BY FRIDAY WITH SHORTWAVE
RIDGING PUSHING INTO THE OHIO VALLEY. NUDGE IN COOLER AIR/DEWPOINTS
WILL BE OCCURRING BEHIND THE FRONT THURSDAY WITH THE SFC HIGH
SHIFTING EWD INTO THE MID ATLANTIC. MOISTURE STAYS MAINLY CONFINED
INTO THE SOUTHEAST THURSDAY BUT ENOUGH EAST FLOW TO ALLOW FOR SOME
ISOLATED MOUNTAIN CONVECTION IN NORTH CAROLINA DURING THE
AFTERNOON/EARLY EVENING.
THU NIGHT-FRIDAY WILL BE MAINLY DRY WITH THE HIGH PRESSURE WEDGING SW
INTO THE MTNS...BUT AGAIN HIGHER MOISTURE STAYS ACROSS THE SOUTHEAST
AND COULD DEFINITELY SHIFT NWD ALONG THE SRN APPALACHIANS LEADING TO
OROGRAPHICALLY INDUCED SHRA/TSRA DURING THE AFTERNOON FRIDAY.
CHANCES STAY SMALL THOUGH.
WENT WITH TEMPS CLOSER TO THE LOCAL MOS THIS PERIOD AS IT HAS
PERFORMED A BIT BETTER THAN THE MET/MAV OVERALL. SHOULD SEE LOWS IN
THE UPPER 40S IN THE MOUNTAINS WED NIGHT TO MID 50S EAST. IT STAYS
SEASONAL INTO FRIDAY WITH HIGHS IN THE 70S AND LOWS IN THE UPPER 40S
TO LOWER 50S.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 1255 PM EDT TUESDAY...
WEEKEND IS LOOKING MAINLY DRY WITH AT OR ABOVE NORMAL TEMPS AS SFC
HIGH WEDGES SOUTHWEST ACROSS THE REGION. CLOUD COVER LOOKS SPARSE
OVERALL...BUT THERE COULD BE STRATUS FORMATION FRI NIGHT WITH SE-E
FLOW ALONG THE BLUE RIDGE. STILL CONFIDENCE NOT HIGH ENOUGH YET TO
GO WITH A BKN-OVC SKY AS HIGH PRESSURE SHOULD CLOSE ENOUGH TO KEEP
THE FLOW LIGHT.
MAKING ADJUSTMENTS HEADING INTO EARLY NEXT WEEK...AS MOST MODELS
AGREE THAT THE UPPER LOW OFF THE SOUTHEAST COAST RETROGRADES TOWARD
FLORIDA BY MONDAY...AND NORTHERN STREAM SHORTWAVE MOVES ACROSS THE
GREAT LAKES. A FRONTAL BOUNDARY APPROACHES THE CENTRAL APPALACHIANS
TUESDAY. MONDAY...MODELS INDICATE ENOUGH ATLANTIC MOISTURE MAY FEED
INTO THE CAROLINAS AND SURGE NWD TOWARD VIRGINIA...THAT WENT WITH
SLIGHT CHANCE OF SHOWERS OR STORMS. BETTER CHANCE ARRIVES BUT STILL
30 POPS TUESDAY WITH SHORTWAVE APPROACHING WITH THE FRONT.
&&
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
AS OF 710 PM EDT TUESDAY...
SCTD STORMS HAVE AGAIN DEVELOPED ALONG THE BLUE RIDGE NEAR THE LOW
LEVEL THETA-E GRADIENT UNDERNEATH THE STALLED FRONT. HOWEVER
COVERAGE NOT NEARLY AS GREAT AS LAST EVENING ATTM WITH MOST TSRA
IN BETWEEN THE TAF SITES. APPEARS THAT EASTERN LOCATIONS SUCH AS
KLYH/KDAN HAVE THE BEST SHOT OF GETTING A DIRECT HIT SO INCLUDED
MORE PREVAILING REDUCTIONS IN SHRA/TSRA THERE. BRIEF MVFR/IFR
CONDS MAY BE REALIZED IN THE HEAVIER STORMS THIS EVENING. ELSW
COVERAGE LOOKS LOW ENOUGH TO JUST INCLUDE A VCTS/VCSH FOR A FEW
HOURS THIS EVENING. THE BOUNDARY WILL MAKE SLOW EASTWARD
PROGRESSION TONIGHT...ALLOWING SKIES TO CLR AND SETTING UP IFR
CIG/VIS KBCB/KLWB/KLYH AND CONDITIONAL IFR CIG/VIS AT KDAN.
CHANCES FOR THIS TO OCCUR GO UP IF THESE TERMINALS GET RAINED ON
THIS EVENING.
WINDS VEER TO THE W AND NW ON WEDNESDAY...WHICH SHOULD HELD ERODE
ANY IFR VIS/CIG IN PLACE EARLY WEDNESDAY MORNING. DESPITE THE
DOWNSLOPING FLOW CAN`T RULE OUT WIDELY SCATTERED STORMS EAST AND
ISOLATED ALONG THE WESTERN RIDGES. HOWEVER LOOKS LIKE THE BEST
CHANCE OF A STORM WILL BE OVER THE SE AT KDAN WHERE INCLUDED AN
AFTERNOON VCTS MENTION.
SOME IFR CIG/VIS AGAIN MAY OCCUR AT KLWB AS HIGH PRESSURE SLIDES
ACROSS THE OHIO VALLEY WEDNESDAY NIGHT. HIGH PRESSURE ACROSS THE
OHIO VALLEY AND LOW PRESSURE OFF THE COAST WILL COMBINE TO PRODUCE
DEEP BUT RATHER LIGHT EASTERLY UPSLOPE FLOW...WHICH MAY WORK ON
LEFT OVER INSTABILITY KLWB/KBLF ON THURSDAY FOR SOME STORMS. HIGH
PRESSURE STRENGTHENS AND MOVES OFF THE NEW ENGLAND COAST THIS
WEEKEND TAKING ON A WEDGE POSITION...HOWEVER ATTM THIS WEDGE
APPEARS TO BE DRY...ALTHOUGH MORE MOISTURE THAN THE MODELS ARE
FORECASTING COULD PRODUCE SOME MVFR CIGS AT TIMES DURING THE
NIGHTS INTO THE WEEKEND.
&&
.HYDROLOGY...
SOME ADDED SHOWERS MAY OCCUR ALONG THE SOUTHERN BLUE RIDGE AND
FOOTHILLS OVERNIGHT BUT ARE NOT EXPECTED TO BE ENOUGH TO CAUSE
WIDESPREAD FLOODING. THUS HAVE DROPPED THE GOING FLASH FLOOD WATCH
ACROSS THE AREA FOR NOW.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...KM/RAB
NEAR TERM...JH/KM
SHORT TERM...NF
LONG TERM...WP
AVIATION...JH/KM/NF
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
210 AM CDT WED MAY 16 2012
.DISCUSSION...
823 PM CDT
AS THE FRONTAL BOUNDARY CONTINUED TO SAG SOUTHEAST ACROSS
SOUTH CENTRAL WISC STRETCHING WEST THROUGH CENTRAL IA...ISOLATED
SHOWERS AND THUNDERSTORMS HAD DEVELOPED. THIS WAS FOCUSED ALONG AN
ENHANCED MID-LVL MOISTURE CONVERGENCE TONGUE...AND CONTINUED TO
PRESS SOUTHEAST TOWARDS NORTHERN IL. THE ENVIRONMENT OVER NORTHERN
IL LATE THIS AFTERNOON/EARLY EVENING...HAD INDICATED STEEP MID-LVL
LAPSE RATES DESPITE A CONTINUED RELATIVELY DRY SOUNDING. WHILE THE
MOISTURE WAS LACKING...FORCING WAS AIDING IN MAINTAINING THE
ISOLATED CONVECTION AND THE MAIN CONCERN CONTINUED TO BE STRONG TO
SEVERE WIND GUSTS. WSR-88D RADAR INDICATED EARLY THIS EVENING
VELOCITY RETURNS NEAR 40 TO AT TIMES 50 KTS. HOWEVER...THE PAST
20-30 MINUTES HAVE INDICATED A STEADY DOWNWARD TREND IN THE
REFLECTIVITY AND VELOCITY PATTERN...HOWEVER MID-LVL LAPSE RATES
HAVE REMAINED RELATIVELY STEEP.
AS WE CONTINUE TO LOSE SFC HEATING AND MOVE TOWARDS THE NOCTURNAL
HOURS...SFC INSTABILITY AND MOISTURE CONVERGENCE WILL DIMINISH.
THIS SHOULD PROVIDE A STEADY DIMINISHING TREND IN THE
PRECIPITATION AND CONVECTION THROUGHOUT THE REMAINDER OF THE
EVENING. OCCASIONAL WIND GUSTS AHEAD OF THE FRONTAL BOUNDARY COULD
STILL APPROACH 50 MPH...HOWEVER ANTICIPATE THAT THIS WILL BE LESS
FREQUENT. WINDS WILL THEN VEER TO NORTHWEST AND EVENTUALLY
NORTHERLY ON THE BACK SIDE OF THE FRONT. IN ADDITION DRY AIR WILL
RAPIDLY PUSH IN BEHIND THIS BOUNDARY...ALLOWING DEW POINTS TO FALL
MAINLY INTO THE UPR 30S TO LOWER 40S. ONCE THE CLOUDS AND PRECIP
PUSHES SOUTH/SOUTHEAST...TEMPS WILL STEADILY RADIATE INTO THE MID
40S. CLOSER TO DOWNTOWN CHICAGO AND THE URBAN HEAT ISLAND...TEMPS
SHOULD BOTTOM OUT ARND 50 DEG.
BEACHLER
//PREV DISCUSSION...
251 PM CDT
FORECAST FOCUS IN NEAR TERM REMAINS COLD FRONTAL PASSAGE THIS
EVENING AND THE POTENTIAL FOR ISOLATED/SCATTERED CONVECTION. AFTER A
MUCH COOLER DAY WEDNESDAY...A WARMING TREND BACK TO SUMMER-LIKE
TEMPERATURES AND EVENTUALLY AND INCREASING POTENTIAL FOR
THUNDERSTORMS IS EXPECTED THROUGH THE WEEKEND.
AT 19Z...SFC ANALYSIS DEPICTS COLD FRONT STRETCHING FROM NEAR GREEN
BAY WISCONSIN...TO AMES IN CENTRAL IOWA. WARM SECTOR AHEAD OF FRONT
IS CHARACTERIZED BY TEMPS IN MID-UPPER 80S FROM NORTHERN IL BACK
INTO EASTERN IA...THOUGH VERY DRY LOW LEVELS AS INDICATED BY SFC DEW
PTS GENERALLY IN THE UPPER 30S TO MID 40S. THIS NOT SURPRISING GIVEN
EXTREMELY DRY LOW-MID LEVELS SEEN IN 12Z RAOBS AT UPSTREAM AT
MPX/OAX...THOUGH THERE IS A NARROW AXIS OF SLIGHTLY HIGHER DWPTS
FROM WESTERN IL INTO NORTHEAST IL. 18Z RAP APPEARS TO HAVE A DECENT
HANDLE ON THE LOW LEVEL MOISTURE FIELD...AND REMAINS CONSISTENT IN
DEVELOPING CONVECTIVE PRECIP AHEAD OF FRONT ACROSS CNTRL/EASTERN WI
AND DEVELOPING IT SOUTHEAST INTO NORTHERN/NORTHEAST IL EARLY THIS
EVENING. DESPITE VIGOROUS MID-LEVEL SHORT WAVE DIGGING SOUTHEAST
ACROSS THE NORTHERN LAKES...STEEP LOW/MID LEVEL LAPSE RATES AND THE
APPROACH OF A RELATIVELY STRONG COLD FRONTAL BOUNDARY...DEARTH OF
LOW LEVEL MOISTURE SUGGESTS IT WILL LIKELY BE DIFFICULT TO DEVELOP
SIGNIFICANT THUNDERSTORM COVERAGE...WITH HIGH LCL/LFC AND FAIRLY
SKINNY CAPE PROFILES OF 200-300 J/KG ALOFT PER RAP SOUNDINGS. THUS
WHILE ISOLATED-SCATTERED STORMS CANT BE RULED OUT COMPLETELY WITH
FROPA EARLY THIS EVENING...CONTINUE TO SUSPECT COVERAGE WILL BE
RELATIVELY LOW AND CONDITIONAL SEVERE THREAT MINIMAL. AS NOTED
PREVIOUSLY...ANY ACTIVITY WHICH DOES DEVELOP SHOULD HAVE A FAIRLY
STRONG DIURNAL COMPONENT AND SHOULD FADE QUICKLY WITH COOLING OF
BOUNDARY LAYER BEYOND SUNSET. WILL CONTINUE TO MAINTAIN ONLY LOW
CHANCE POPS.
HIGH PRESSURE WILL THEN BUILD ACROSS THE GREAT LAKES REGION
WEDNESDAY IN THE WAKE OF THE MID-LEVEL WAVE AND COLD FRONT. MUCH
COOLER TEMPS THAN TODAY CAN BE EXPECTED...RANGING FROM AROUND 60
NEAR THE LAKE MICHIGAN SHORE TO THE LOW 70S IN THE FAR WEST/SOUTH
REACHES OF THE CWA. FLAT UPPER LEVEL RIDGE THEN SPREADS ACROSS THE
MIDWEST THURSDAY...WITH LOW LEVEL WARM ADVECTION FOCUSING ACROSS THE
UPPER MISSISSIPPI VALLEY AND ACROSS THE NORTHERN LAKES FRIDAY. AXIS
OF LOW LEVEL 40-50 KT JET KEEPS THUNDERSTORM FOCUS NORTH/NORTHWEST
OF THE CWA THROUGH THIS TIME. UPPER RIDGE STRENGTHENS OVER THE
MIDWEST INTO THE WEEKEND AS BROAD TROUGH PUSHES EAST ACROSS THE
WESTERN HALF OF THE CONUS. SOUTHEAST/SOUTH FLOW THROUGH THE PERIOD
WILL LEAD TO TEMPS GRADUALLY WARMING FROM THE 70S THURSDAY INTO THE
LOW-MID80S FRI AND MID 80S SAT. LOW LEVEL MOISTURE WILL ALSO
GRADUALLY INCREASE FROM THE WEST/SOUTHWEST OVER THE WEEKEND AS
WESTERN TROUGH AND COLD FRONT SLOWLY APPROACH. GUIDANCE HAS SLOWED
FRONTAL ARRIVAL SOMEWHAT...HOLDING OFF GREATER PRECIP/THUNDERSTORM
THREAT UNTIL SUNDAY NIGHT AND MONDAY. UPPER TROUGH THEN MOVES SLOWLY
ACROSS THE AREA EARLY NEXT WEEK WITH COOLER WEATHER AS LOW LEVEL
FLOW BECOMES NORTHERLY BEHIND THE FRONT.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
NORTHERLY WIND GUSTS OVER THE NEXT COUPLE OF HOURS.
KJB
//DISCUSSION...UPDATED 06Z...
A COLD FRONT HAS JUST PUSHED ACROSS THE TERMINALS EARLY THIS
MORNING. WINDS DIRECTLY BEHIND THIS FRONT HAVE INCREASED OUT OF THE
NORTH WITH GUSTS UP TO 30 KT. THESE STRONG WIND GUSTS WILL ONLY LAST
FOR THE NEXT 1 TO 2 HOURS AS STRONG PRESSURE RISES OVERSPREAD THE
AREA. NORTHEASTERLY FLOW WILL CONTINUE THROUGH THE DAY TODAY
AHEAD OF HIGH PRESSURE BUILDING IN FROM THE NORTH. WIND SPEEDS
SHOULD GENERALLY BE LIGHT...WITH ONLY ABOUT 10 TO 15 KT OF FLOW. THE
SURFACE HIGH PRESSURE SYSTEM WILL BUILD ACROSS THE REGION LATER THIS
EVENING...THIS WILL PROVIDE A PERIOD OF LIGHT AND VARIABLE WINDS
GRADUALLY SHIFTING TO THE SOUTHEAST.
KJB
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
HIGH FOR ALL FORECAST ELEMENTS.
KJB
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
* THURSDAY THROUGH SATURDAY...VFR.
* SUNDAY...CHANCE OF TSRA. GUSTY SOUTHWEST WINDS.
* MONDAY...CHANCE OF TSRA.
SHEA
&&
.MARINE...
208 AM CDT
A COLD FRONT HAS PUSHED SOUTH OF THE LAKE EARLY THIS MORNING. IN
THE WAKE OF THIS FRONT...NORTHERLY WINDS WINDS CONTINUE TO GUST
IN THE 25 TO 30 KT RANGE ACROSS THE SOUTHERN HALF OF LAKE
MICHIGAN. I OPTED TO ISSUE A SMALL CRAFT ADVISORY EARLIER FOR THE
ILLINOIS AND INDIANA NEAR SHORES UNTIL 15 UTC TODAY DUE TO THESE
STRONG WINDS UP TO 30 KT AND ALSO FOR THE BUILDING WAVES...WHICH
ARE EXPECTED TO BE AT OR SLIGHTLY ABOVE 4 FEET THROUGH THE MORNING
TODAY. OVERALL...I EXPECT THESE STRONG NORTHERLY WINDS GUSTS TO
SLOWLY DIMINISH LATER THIS MORNING AS SURFACE HIGH PRESSURE BUILDS
IN ACROSS THE LAKE LATER IN THE DAY. A PERIOD OF LIGHT AND
VARIABLE WINDS ARE EXPECTED TONIGHT BEFORE THE WINDS BECOME
SOUTHEASTERLY BY THURSDAY AS THE SURFACE HIGH SHIFTS EAST OF THE
LAKE. ONCE THIS OCCURS...THERE WILL BE A PROLONGED PERIOD OF
SOUTHERLY WINDS ACROSS LAKE MICHIGAN AS A LARGE AREA OF LOW
PRESSURE TAKES SHAPE ACROSS THE PLAINS. WIND SPEEDS MAY INCREASE
SOME BY THE WEEKEND...BUT OVERALL 10 TO 20 KT FLOW LOOKS TO BE THE
PRIMARY WIND SPEED.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 10 AM WEDNESDAY.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1247 AM CDT WED MAY 16 2012
.DISCUSSION...
823 PM CDT
AS THE FRONTAL BOUNDARY CONTINUED TO SAG SOUTHEAST ACROSS
SOUTH CENTRAL WISC STRETCHING WEST THROUGH CENTRAL IA...ISOLATED
SHOWERS AND THUNDERSTORMS HAD DEVELOPED. THIS WAS FOCUSED ALONG AN
ENHANCED MID-LVL MOISTURE CONVERGENCE TONGUE...AND CONTINUED TO
PRESS SOUTHEAST TOWARDS NORTHERN IL. THE ENVIRONMENT OVER NORTHERN
IL LATE THIS AFTERNOON/EARLY EVENING...HAD INDICATED STEEP MID-LVL
LAPSE RATES DESPITE A CONTINUED RELATIVELY DRY SOUNDING. WHILE THE
MOISTURE WAS LACKING...FORCING WAS AIDING IN MAINTAINING THE
ISOLATED CONVECTION AND THE MAIN CONCERN CONTINUED TO BE STRONG TO
SEVERE WIND GUSTS. WSR-88D RADAR INDICATED EARLY THIS EVENING
VELOCITY RETURNS NEAR 40 TO AT TIMES 50 KTS. HOWEVER...THE PAST
20-30 MINUTES HAVE INDICATED A STEADY DOWNWARD TREND IN THE
REFLECTIVITY AND VELOCITY PATTERN...HOWEVER MID-LVL LAPSE RATES
HAVE REMAINED RELATIVELY STEEP.
AS WE CONTINUE TO LOSE SFC HEATING AND MOVE TOWARDS THE NOCTURNAL
HOURS...SFC INSTABILITY AND MOISTURE CONVERGENCE WILL DIMINISH.
THIS SHOULD PROVIDE A STEADY DIMINISHING TREND IN THE
PRECIPITATION AND CONVECTION THROUGHOUT THE REMAINDER OF THE
EVENING. OCCASIONAL WIND GUSTS AHEAD OF THE FRONTAL BOUNDARY COULD
STILL APPROACH 50 MPH...HOWEVER ANTICIPATE THAT THIS WILL BE LESS
FREQUENT. WINDS WILL THEN VEER TO NORTHWEST AND EVENTUALLY
NORTHERLY ON THE BACK SIDE OF THE FRONT. IN ADDITION DRY AIR WILL
RAPIDLY PUSH IN BEHIND THIS BOUNDARY...ALLOWING DEW POINTS TO FALL
MAINLY INTO THE UPR 30S TO LOWER 40S. ONCE THE CLOUDS AND PRECIP
PUSHES SOUTH/SOUTHEAST...TEMPS WILL STEADILY RADIATE INTO THE MID
40S. CLOSER TO DOWNTOWN CHICAGO AND THE URBAN HEAT ISLAND...TEMPS
SHOULD BOTTOM OUT ARND 50 DEG.
BEACHLER
//PREV DISCUSSION...
251 PM CDT
FORECAST FOCUS IN NEAR TERM REMAINS COLD FRONTAL PASSAGE THIS
EVENING AND THE POTENTIAL FOR ISOLATED/SCATTERED CONVECTION. AFTER A
MUCH COOLER DAY WEDNESDAY...A WARMING TREND BACK TO SUMMER-LIKE
TEMPERATURES AND EVENTUALLY AND INCREASING POTENTIAL FOR
THUNDERSTORMS IS EXPECTED THROUGH THE WEEKEND.
AT 19Z...SFC ANALYSIS DEPICTS COLD FRONT STRETCHING FROM NEAR GREEN
BAY WISCONSIN...TO AMES IN CENTRAL IOWA. WARM SECTOR AHEAD OF FRONT
IS CHARACTERIZED BY TEMPS IN MID-UPPER 80S FROM NORTHERN IL BACK
INTO EASTERN IA...THOUGH VERY DRY LOW LEVELS AS INDICATED BY SFC DEW
PTS GENERALLY IN THE UPPER 30S TO MID 40S. THIS NOT SURPRISING GIVEN
EXTREMELY DRY LOW-MID LEVELS SEEN IN 12Z RAOBS AT UPSTREAM AT
MPX/OAX...THOUGH THERE IS A NARROW AXIS OF SLIGHTLY HIGHER DWPTS
FROM WESTERN IL INTO NORTHEAST IL. 18Z RAP APPEARS TO HAVE A DECENT
HANDLE ON THE LOW LEVEL MOISTURE FIELD...AND REMAINS CONSISTENT IN
DEVELOPING CONVECTIVE PRECIP AHEAD OF FRONT ACROSS CNTRL/EASTERN WI
AND DEVELOPING IT SOUTHEAST INTO NORTHERN/NORTHEAST IL EARLY THIS
EVENING. DESPITE VIGOROUS MID-LEVEL SHORT WAVE DIGGING SOUTHEAST
ACROSS THE NORTHERN LAKES...STEEP LOW/MID LEVEL LAPSE RATES AND THE
APPROACH OF A RELATIVELY STRONG COLD FRONTAL BOUNDARY...DEARTH OF
LOW LEVEL MOISTURE SUGGESTS IT WILL LIKELY BE DIFFICULT TO DEVELOP
SIGNIFICANT THUNDERSTORM COVERAGE...WITH HIGH LCL/LFC AND FAIRLY
SKINNY CAPE PROFILES OF 200-300 J/KG ALOFT PER RAP SOUNDINGS. THUS
WHILE ISOLATED-SCATTERED STORMS CANT BE RULED OUT COMPLETELY WITH
FROPA EARLY THIS EVENING...CONTINUE TO SUSPECT COVERAGE WILL BE
RELATIVELY LOW AND CONDITIONAL SEVERE THREAT MINIMAL. AS NOTED
PREVIOUSLY...ANY ACTIVITY WHICH DOES DEVELOP SHOULD HAVE A FAIRLY
STRONG DIURNAL COMPONENT AND SHOULD FADE QUICKLY WITH COOLING OF
BOUNDARY LAYER BEYOND SUNSET. WILL CONTINUE TO MAINTAIN ONLY LOW
CHANCE POPS.
HIGH PRESSURE WILL THEN BUILD ACROSS THE GREAT LAKES REGION
WEDNESDAY IN THE WAKE OF THE MID-LEVEL WAVE AND COLD FRONT. MUCH
COOLER TEMPS THAN TODAY CAN BE EXPECTED...RANGING FROM AROUND 60
NEAR THE LAKE MICHIGAN SHORE TO THE LOW 70S IN THE FAR WEST/SOUTH
REACHES OF THE CWA. FLAT UPPER LEVEL RIDGE THEN SPREADS ACROSS THE
MIDWEST THURSDAY...WITH LOW LEVEL WARM ADVECTION FOCUSING ACROSS THE
UPPER MISSISSIPPI VALLEY AND ACROSS THE NORTHERN LAKES FRIDAY. AXIS
OF LOW LEVEL 40-50 KT JET KEEPS THUNDERSTORM FOCUS NORTH/NORTHWEST
OF THE CWA THROUGH THIS TIME. UPPER RIDGE STRENGTHENS OVER THE
MIDWEST INTO THE WEEKEND AS BROAD TROUGH PUSHES EAST ACROSS THE
WESTERN HALF OF THE CONUS. SOUTHEAST/SOUTH FLOW THROUGH THE PERIOD
WILL LEAD TO TEMPS GRADUALLY WARMING FROM THE 70S THURSDAY INTO THE
LOW-MID80S FRI AND MID 80S SAT. LOW LEVEL MOISTURE WILL ALSO
GRADUALLY INCREASE FROM THE WEST/SOUTHWEST OVER THE WEEKEND AS
WESTERN TROUGH AND COLD FRONT SLOWLY APPROACH. GUIDANCE HAS SLOWED
FRONTAL ARRIVAL SOMEWHAT...HOLDING OFF GREATER PRECIP/THUNDERSTORM
THREAT UNTIL SUNDAY NIGHT AND MONDAY. UPPER TROUGH THEN MOVES SLOWLY
ACROSS THE AREA EARLY NEXT WEEK WITH COOLER WEATHER AS LOW LEVEL
FLOW BECOMES NORTHERLY BEHIND THE FRONT.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
NORTHERLY WIND GUSTS OVER THE NEXT COUPLE OF HOURS.
KJB
//DISCUSSION...UPDATED 06Z...
A COLD FRONT HAS JUST PUSHED ACROSS THE TERMINALS EARLY THIS
MORNING. WINDS DIRECTLY BEHIND THIS FRONT HAVE INCREASED OUT OF THE
NORTH WITH GUSTS UP TO 30 KT. THESE STRONG WIND GUSTS WILL ONLY LAST
FOR THE NEXT 1 TO 2 HOURS AS STRONG PRESSURE RISES OVERSPREAD THE
AREA. NORTHEASTERLY FLOW WILL CONTINUE THROUGH THE DAY TODAY
AHEAD OF HIGH PRESSURE BUILDING IN FROM THE NORTH. WIND SPEEDS
SHOULD GENERALLY BE LIGHT...WITH ONLY ABOUT 10 TO 15 KT OF FLOW. THE
SURFACE HIGH PRESSURE SYSTEM WILL BUILD ACROSS THE REGION LATER THIS
EVENING...THIS WILL PROVIDE A PERIOD OF LIGHT AND VARIABLE WINDS
GRADUALLY SHIFTING TO THE SOUTHEAST.
KJB
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
HIGH FOR ALL FORECAST ELEMENTS.
KJB
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
* THURSDAY THROUGH SATURDAY...VFR.
* SUNDAY...CHANCE OF TSRA. GUSTY SOUTHWEST WINDS.
* MONDAY...CHANCE OF TSRA.
SHEA
&&
.MARINE...
353 PM CDT
A COLD FRONT TRAILING BACK SOUTHWESTWARD FROM LOW PRESSURE OVER
FAR EASTERN ONTARIO BETWEEN JAMES BAY AND GEORGIAN BAY...ACROSS
THE FAR EASTERN UPPER PENINSULA OF MI...CENTRAL WI AND SE IA WILL
CONTINUE TO PUSH SE ACROSS THE UPPER GREAT LAKES AND MID MS VALLEY
THIS EVENING AS THE LOW CONTINUES TO MOVE E TO CENTRAL QUEBEC
DURING THE NIGHT. HIGH PRESSURE CENTERED OVER SOUTHERN MANITOBA
AND EXTENDING S ACROSS THE NORTHERN PLAINS WILL BUILD ACROSS THE
UPPER MIDWEST AND MID MO VALLEY OVERNIGHT BEHIND THE COLD FRONT.
COLD AIR ADVECTION AND A SIGNIFICANT 3 HR PRESSURE RISE CENTER OF
5-6 MB WAS MOVING SE ACROSS CENTRAL LAKE SUPERIOR AND THE U.P. OF
MI GENERATING SOME NW GUSTS TO AROUND 30 KT BEHIND THE COLD FRONT.
THIS PRESSURE RISE CENTER IS EXPECTED TO SWING ACROSS NORTHERN
LAKE MI THIS EVE CAUSING SOME GUSTY NW AND N WINDS MAINLY ON THE N
PORTION OF THE LAKE.
HIGH PRESSURE CENTERED OVER SOUTHERN MANITOBA AND EXTENDING S
ACROSS THE NORTHERN PLAINS WILL BUILD ACROSS THE UPPER MIDWEST AND
MID MO VALLEY OVERNIGHT BEHIND THE COLD FRONT WITH THE PRESSURE
GRADIENT OVER LAKE MI GRADUALLY WEAKENING AND THE RESULTANT WINDS
SLACKING. THIS HIGH THEN MOVES E OVER THE UPPER GREAT LAKES DURING
WED BRINGING LIGHTER WINDS TO THE LAKE. AS THE HIGH SHIFTS FURTHER
E TO THE LOWER GREAT LAKES DURING THU SE WINDS WILL START TO
SLOWLY INCREASE THU NIGHT AND FRI AS LOW PRESSURE MOVES E OVER THE
CENTRAL PLAINS.
TRS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 10 AM WEDNESDAY.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
150 AM EDT WED MAY 16 2012
.AVIATION...
HIRES GUIDANCE OUT TO LUNCH THIS EVENING WITH WHOPPING TEMP AND
DEWPOINT ERRORS RESULTING IN POOR HANDLING OF RESIDUAL CONVECTION
ALONG COLD FRONT MOVING THROUGH KSBN AT THIS TIME. RADAR SHOWING A
SLIGHT FLARE UP ALONG ELEVATED THETA E GRADIENT AND APPROACHING
850MB TROUGH. CONVECTION REMAINS SPOTTY AND CONFINED TO KSBN AREA
FOR NEXT HOUR TO TWO AT MOST SO ACCOUNTED FOR VIS RESTRICTION DURING
THIS PERIOD. UNLESS ADDITIONAL DEVELOPMENT TAKES PLACE DO NOT EXPECT
PCPN TO REACH KFWA. WINDS BECOME NORTH TO NORTHEAST BEHIND FRONT
WITH DRYING EXPECTED TOWARD DAYBREAK. SHOULD SEE MID LEVEL CLOUDS
DECREASE FROM WEST TO EAST TOWARD SUNRISE AND SHORTLY AFTER.
&&
.UPDATE...
HIRES GUIDANCE SHOWING SERIOUS ERRORS WITH TEMPS AND DEW POINTS THIS
EVENING ACROSS THE AREA. RUC...HRRR...NAM12...LOCAL WRF...SREF...ALL
TOO COOL WITH HOURLY TEMPS BY 7 TO 12 DEGREES AT 05Z AND ALSO
STRUGGLING WITH EXTRAORDINARY DEW POINT DISCONTINUITIES ACROSS THE
CWA. EARLIER MIXING AHEAD OF FRONT ALLOWED DRIER AIR TO WORK TO
SURFACE WHILE MOISTURE HAS BEEN POOLING IMMEDIATELY ALONG FRONT THIS
EVENING AND NOW DRIER AIR IS WORKING IN FROM NORTH IN WAKE OF COLD
FRONT. TRIED TO ADJUST GRIDS TO REFLECT THIS WITH COOLING AND DRYING
THROUGH THE NIGHT. THE WARMER TEMPS AND POOLING MOISTURE HAS ALLOWED
A POCKET OF CONVECTION TO PERSIST NEAR KSBN WITH A SLOW DRIFT EAST.
ADJUSTED GRIDS SLIGHTLY TO ACCOUNT FOR THIS FOR A FEW MORE HOURS
OVERNIGHT. REMAINDER OF FORECAST UNCHANGED AT THIS TIME.
&&
.PREV DISCUSSION... /ISSUED 430 PM EDT TUE MAY 15 2012/
SHORT TERM.../TONIGHT-WED NGT/
CDFNT MOVG ACROSS WI/IA THIS AFTN WILL MOVE SE ACROSS OUR CWA
TONIGHT. BKN HIGH BASED CU AND ISOLATED LIGHTNING STRIKES ALONG
FRONT OVER WI/IA ATTM. SFC OBS AND 12Z UPR AIR ANALYSIS SUGGESTS
LATEST NCEP MODELS CONT TO BE TOO MOIST IN LOW LEVELS... THUS
CONFIDENCE IN BKN LINE OF SHOWERS/TSTMS DVLPG FROM MI-SE IA BY 00Z
AS DEPICTED BY LATEST 4KM SPC WRF IS LOW. HRRR INDICATING
CONSIDERABLY LOWER CHC OF CONVECTION REACHING OUR AREA AND APPEARS
TO BE HANDLING THE SFC DWPTS AHEAD OF THE FRONT A LITTLE BETTER. IN
EITHER CASE... ANY SHOWERS/TSTMS WHICH DEVELOP ALONG FRONT LATE
THIS AFTN/EARLY EVE SHOULD BE IN A WKNG/DISSIPATING STAGE UPON
REACHING OUR CWA GIVEN DRY AIRMASS IN PLACE AND DIURNAL
STABILIZATION. ALTHOUGH CONFIDENCE LOW IN CONVECTION REACHING OUR
AREA... FELT GOING LOW CHC OF TSTMS TONIGHT WORTH LEAVING IN FCST
ATTM. GIVEN STEEP LAPSE RATES ABOVE DVLPG SHALLOW NOCTURNAL SFC
BASED INVERSION... POTENTIAL FOR SOME GUSTY WINDS IF CONVECTION
DOES REACH OUR CWA.
HIGH PRESSURE BUILDING INTO THE AREA BEHIND THE FRONT WED WILL
RESULT IN CLEARING SKIES. FAIRLY STRONG CAA SHOULD HOLD TEMPS DOWN
ABOUT 10F FROM TODAYS READINGS DESPITE SUNNY SKIES MOST OF THE DAY.
WITH HIGH MOVG OVERHEAD WED NGT LIGHT WINDS AND DRY AIRMASS WILL
RESULT IN GOOD RADIATIONAL COOLING WITH LOWS IN THE L-M40S ACROSS
THE AREA.
LONG TERM...
PROGRESSIVE PATTN ALOFT CONTS TO HOLD SWAY THIS PD. LEAD SW TROUGH
OVR SRN ON THIS AFTN WILL RAPIDLY DRIVE EWD UP THROUGH THE ST LAW
VALLEY THU AS SFC RIDGING SHIFTS EWD W/ROBUST WAA DVLPG DURING THE
DAY. MEXMOS APPROXIMATION STILL HOLDS AND SEE NO REASON TO CHG
ANYTHING.
AFT THAT...SIG UPR RIDGING DVLPS EWD OF WRN US TROUGHING AND
INTENSIFIES ACRS THE MID ATL COAST THIS WEEKEND. THERMAL RIDGE
INBTWN WILL BE QUITE WARM FOR MID MAY STANDARDS WITH LOW-MID 80S
XPCD FRI-SUN. EJECTING WRN TROUGH SAT PROGGED TO QUICKLY DEAMPLIFY
EWD MON IN RESPONSE TO DOWNSTREAM UPR RIDGING AND RENEWED FOCUS ON A
MORE SIG WAVE TRAIN ENTERING NWPAC/SW CANADA. IN ADDN...CONTD
SUGGESTION OF A TROPICAL DISTURBANCE OVR THE WRN CARIBBEAN WILL
ELIMINATE ANY SIG GOMEX MSTR RTN. GIVEN CONTD POOR MODEL HANDLING OF
BNDRY LYR MSTR AND XPCD WKNG FNTL SYS...WILL SLASH GOING POPS LWR
MON/MON NIGHT. REMAINDER ON TRACK.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 4 PM EDT
WEDNESDAY FOR LMZ043-046.
&&
$$
SHORT TERM...JT
LONG TERM...T
AVIATION...LASHLEY
UPDATE...LASHLEY
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
520 AM EDT WED MAY 16 2012
.SYNOPSIS...
ISSUED AT 518 AM EDT WED MAY 16 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE FROM
THE ROCKIES INTO SASK AND A DOWNSTREAM TROUGH FROM HUDSON BAY INTO
THE CNTRL GREAT LAKES RESULTING IN NW FLOW THROUGH UPPER MI. AT THE
SFC...HIGH PRES FROM MANITOBA INTO WRN MN WAS BUILDING INTO THE WRN
GREAT LAKES. SUBSIDENCE AND DRY ADVECTION IN THE WAKE OF THE MID
LEVEL TROUGH HAS BROUGHT CLEAR SKIES TO THE AREA ALONG WITH
DIMINISHING WINDS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 518 AM EDT WED MAY 16 2012
TODAY...SUNSHINE AND MIXING IN THE VERY DRY AIRMASS (PWAT VALUES
DOWN TO NEAR 0.25 INCH) OVER THE AREA WILL BOOST TEMPS INTO THE
LOWER TO MID 60S BUT PUSH DEWPOINTS DOWN TO NEAR 20 OVER INLAND
LOCATIONS THIS AFTERNOON. THIS WILL RESULT IN RH VALUES IN THE 20 TO
25 PCT RANGE. FORTUNATELY WINDS WILL BE RELATIVELY LIGHT...ONLY
INCREASING INTO THE 10 TO 15 MPH RANGE THIS AFTERNOON.
TONIGHT...AS THE MID LEVEL RIDGE EDGES TO THE EAST...DOWNSTREAM WAA
AND 300K-305K ISENTROPIC LIFT WILL BRING AN INCREASE IN MID LEVEL
CLOUDS FROM NW ONTARIO INTO UPPER MI. HOWEVER...LIGHT WINDS AND
MAINLY CLEAR SKIES TIL LATE NIGHT OVER THE EAST WILL RESULT IN
DECENT RADIATIONAL COOLING WITH TEMPS FALLING INTO THE LOWER 30S.
A FROST ADVY MAY BE NEEDED FOR THE INTERIOR EAST HALF...ESPECIALLY
IF THERE IS A TREND TOWARD LATER INCREASE IN CLOUDS.
THURSDAY...EXPECT THE POSITION OF THE 850 MB WARM FRONT AND GREATER
LOW LEVEL THETA-E ADVECTION...PER NAM/GFS/ECMWF...TO REMAIN FAR
ENOUGH TO THE SOUTH AND WEST TO KEEP BEST PCPN CHANCES OVER NRN
MN AND NRN WI. HOWEVER...SOME SHRA MAY BRUSH MAINLY THE SW PORTION
OF THE CWA. CLOUD COVER SHOULD BE THICK ENOUGH TO KEEP TEMPS INTO
THE MID TO UPPER 60S...EVEN AS 850 MB TEMPS CLIMB INTO THE 7C TO 10C
RANGE.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 518 AM EDT WED MAY 16 2012
NAM STARTS OFF WITH A 500 MB TROUGH OVER THE WESTERN U.S. AND
SHORTWAVE IN THE CENTRAL PLAINS 00Z FRI WITH RIDGING INTO THE UPPER
MISSISSIPPI RIVER VALLEY AND TROUGHING IN THE SERN U.S. AND ALSO IN
NEW ENGLAND. UPPER LEVEL RIDGING BUILDS INTO THE UPPER GREAT LAKES
THIS PERIOD.
NAM BRINGS THIS SHORTWAVE NORTHEAST FRIDAY WITH 850-500 MB Q-VECTOR
CONVERGENCE AND DEEPER MOISTURE MOVING THROUGH THE AREA BEFORE BOTH
GET PUSHED NORTH FRIDAY NIGHT. NAM ALSO SHOWS SOME ISENTROPIC LIFT
AND LIMITED MOISTURE THU NIGHT WITH A WARM FRONT MOVING THROUGH THE
AREA BEFORE THE LIFT AND MOISTURE PUSH NORTH ON FRIDAY. GFS SHOWS
ABOUT THE SAME THING FOR ISENTROPIC LIFT ON I300K-I310K SURFACES AND
MOISTURE THU NIGHT INTO FRI. GFS AND ECMWF ALSO SHOW 850-500 MB
Q-VECTOR CONVERGENCE OVER THE AREA THROUGH 12Z SAT. WILL PUT IN
CHANCE TO SLIGHT CHANCE POPS FOR THIS WARM FRONT THU NIGHT THROUGH
FRIDAY NIGHT ACROSS THE AREA. BEST CHANCES FOR PCPN WILL BE ACROSS
THE WEST AND LOWEST IN THE EAST AWAY FROM THE BETTER MOISTURE AND
DYNAMICS. DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST FOR
TEMPERATURES.
IN THE EXTENDED...ECMWF SHOWS A 500 MB RIDGE OVER THE UPPER GREAT
LAKES WITH TROUGHING IN THE WESTERN U.S. 12Z WITH A TROUGH IN THE
EASTERN U.S. AND A WEAK CLOSED 500 MB LOW OVER THE SERN U.S. PATTERN
CHANGES LITTLE 12Z SUNDAY BEFORE THE TROUGH IN THE WESTERN U.S.
MOVES INTO THE UPPER GREAT LAKES SUN NIGHT THROUGH TUE. GFS SHOWS
ABOUT THE SAME THING THROUGH SUNDAY. WHAT THIS WILL MEAN IS A VERY
WARM PERIOD AT THE START OF THE WEEKEND...THEN A COOL DOWN INTO
EARLY NEXT WEEK. TEMPERATURES WILL STILL BE AT OR ABOVE NORMAL
THOUGH. WITH THE UPPER LEVEL TROUGH REMAINING INTO TUE...AFTER
CHANCE TO LIKELY POPS ON SUNDAY WITH THE COLD FRONT...SLIGHT CHANCE
POPS FOR MONDAY INTO TUESDAY STILL SEEM WARRANTED. DID BUMP HIGHS UP
A BIT ON SATURDAY AS PLENTY OF SUNSHINE AND 850 MB TEMPERATURES TO
14C TO 16C...THIS WOULD GIVE HIGHS IN THE LOWER TO MID 80S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 139 AM EDT WED MAY 16 2012
ALTHOUGH THERE WL BE A GRADUAL INCRS IN HI CLDS LATER...EXPECT VFR
CONDITIONS AND LIGHT WINDS THIS FCST PERIOD WITH DRY HI PRES
DOMINATING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 518 AM EDT WED MAY 16 2012
WINDS WILL BE BELOW 25 KNOTS THROUGH THE PERIOD. A HIGH PRESSURE
RIDGE WILL BUILD INTO THE REGION TODAY THROUGH THURSDAY. A LOW
PRESSURE TROUGH WILL APPROACH FROM THE PLAINS AND PUSH A WARM FRONT
ACROSS THE AREA THURSDAY NIGHT INTO FRIDAY. A COLD FRONT WILL MOVE
THROUGH THE UPPER GREAT LAKES ON SUNDAY WITH COOLER HIGH PRESSURE
BUILDING BACK IN FOR EARLY NEXT WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...07
AVIATION...JLB
MARINE...07
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1129 PM CDT TUE MAY 15 2012
.AVIATION... /06Z TAF ISSUANCE/
NOT TOO MANY CONCERNS AHEAD AS A LARGE HIGH PRESSURE SYSTEM PASSES
ACROSS THE TAF SITES. VFR CONDITIONS TO PREVAIL. LIGHT NORTH WINDS
OVERNIGHT WILL BECOME SOUTH FOR THE MN TAF SITES AND WEST FOR THE
WI ONES. WINDS WILL INCREASE DURING THE AFTERNOON AT KAXN AND
KRWF WITH GUSTS OF 18-20 KNOTS POSSIBLE FOR A FEW HOURS.
KMSP...VFR CONDITIONS TO PREVAIL THROUGH THE PERIOD. LIGHT NORTH
WINDS OVERNIGHT WILL VEER TO THE EAST WEDNESDAY MORNING AND THEN
BECOME SOUTH LESS THAN 10 KNOTS IN THE AFTERNOON.
OUTLOOK...
THU-FRI...SLIGHT CHANCE OF SHRA/TSRA...MVFR CEILINGS POSSIBLE.
SAT-SUN...SHRA/TSRA LIKELY WITH MVFR/IFR POSSIBLE.
&&
.DISCUSSION... /ISSUED 312 PM CDT TUE MAY 15 2012/
A FAIRLY PROGRESSIVE UPPER LEVEL PATTERN WILL BE THE RULE ACROSS
THE NORTHERN CONUS OVER THE UPCOMING WEEK. LATEST WATER VAPOR
IMAGERY AND RAP ANALYSIS SHOW A BROAD RIDGE OVER THE WEST... WITH
TROUGHING OVER THE EAST. A HEALTHY SHORTWAVE CAN BE SEEN ROTATING
SOUTHEAST ACROSS THE NORTHERN GREAT LAKES AT THE CURRENT TIME.
THIS FEATURE IS HELPING TO ENHANCE THE CU FIELD ACROSS NORTHEAST
MINNESOTA AND NORTHERN WISCONSIN... BUT ANY SHRA ARE STAYING WELL
NORTH AND EAST OF OUR AREA. THE WESTERN RIDGE WILL MOVE EAST OVER
THE NEXT FEW DAYS... GENERALLY BRINGING DRY WEATHER AND A WARMING
TREND. HOWEVER... CHANCES FOR SHRA/TSRA WILL STEADILY INCREASE
DURING THE SECOND HALF OF THE WEEK INTO THE WEEKEND... WITH AN
UPPER TROUGH EVENTUALLY PUSHING THROUGH TOWARD THE END OF THE
WEEKEND... WHICH WILL HELP PUSH A SURFACE LOW AND FRONTAL BOUNDARY
ACROSS THE REGION. FAVORED THE NAM FOR THE SHORT TERM DETAILS...
THEN TRENDED TOWARD A BLEND OF THE PREVIOUS FORECAST AND ECMWF...
WHICH WAS A BIT SLOWER TO KICK THE RIDGE EASTWARD. THE LATEST
ECMWF IS A BIT FASTER HOWEVER... WHICH MAKES THE WEEKEND FORECAST
TRICKY IN TERMS OF PINPOINTING WHEN PCPN IS MOST LIKELY.
SURFACE RIDGE WILL CONTINUE TO BUILD SOUTHEAST ACROSS THE AREA
TONIGHT... FURTHER DRYING OUT DEWPOINTS THROUGH THE EARLY
EVENING... WITH A REASONABLY COOL NIGHT EXPECTED FOR THE OVERNIGHT
HOURS. THE WESTERN PART OF THE AREA SHOULD MANAGE TO GET ON THE
BACKSIDE OF THE RIDGE BY TOMORROW AFTERNOON... WITH SOME RETURN
FLOW WORKING INTO THAT AREA BY EVENING. A BETTER LOW LEVEL JET AND
WARM ADVECTION LOOK TO SETUP ACROSS THE AREA LATER WEDNESDAY
NIGHT AS LOW PRESSURE EDGED OUT INTO THE HIGH PLAINS. A LOOK AT
FORECAST 850-500MB DIFFERENTIAL THETA-E VALUES... 850MB THETA-E
ADVECTION... AND ISENTROPIC ASCENT ON THE 305K SURFACE SUGGEST
THAT ELEVATED SHRA/TSRA MAY INITIALLY GET GOING OVER THE NORTH
CENTRAL PART OF THE AREA... BUT SHOULD WORK ITS WAY SOUTHEAST
THROUGH THE OVERNIGHT AS SATURATION OCCURS SOUTHWARD ALONG THE
ELEVATED FRONTAL BOUNDARY. SOME ACTIVITY SHOULD REMAIN FOCUSED
NEAR THE FRONTAL BOUNDARY THROUGH THE DAY ON THURSDAY INTO
THURSDAY NIGHT AS WARM ADVECTION PERSISTS IN AN AREA OF CONVECTIVE
INSTABILITY. HOWEVER... BY FRIDAY THROUGH FRIDAY NIGHT THE FOCUS OF
THIS ACTIVITY LOOKS LIKE IT SHOULD SHIFT NORTHEAST OF MOST OF THE
AREA... SO TRIMMED BACK POPS DURING THAT TIME FRAME TO MAINLY
INCLUDE ONLY THE FAR NORTHERN PORTION OF THE CWFA. BY SATURDAY WE
WILL START TO FEEL THE INFLUENCE OF THE APPROACHING SURFACE FRONT
AS THE AIRMASS ACROSS THE REGION CONTINUES TO DESTABILIZE... SO
INCREASED POPS ACROSS MUCH OF THE AREA FROM WEST TO EAST. THE
BOUNDARY ITSELF LOOKS TO MOVE ACROSS THE REGION SATURDAY NIGHT OR
EARLY SUNDAY... BUT AT THIS POINT THAT TIMING COULD EASILY SHIFT
FOR 12-24 HOURS... WHICH WILL CERTAINLY HAVE AN IMPACT ON WHEN
WIDESPREAD SHRA/TSRA IS MOST LIKELY... AS WELL AS WHETHER MUCH IF
ANY SEVERE WEATHER WILL OCCUR. THINGS LOOK TO DRY OUT MONDAY AND
TUESDAY IN THE WAKE OF THE FRONT AND UPPER TROUGH... WITH HIGH
PRESSURE QUICKLY SETTLING IN ON MONDAY... THEN THE PROGRESSIVE
PATTERN BRINGING RETURN FLOW BACK INTO THE REGION BY TUESDAY
AFTERNOON.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
RAH/TRH
AREA FORECAST DISCUSSION...UPDATED
NWS BLACKSBURG VA
200 PM EDT WED MAY 16 2012
.SYNOPSIS...
THE PESKY WEAK STATIONARY BOUNDARY...WHICH HAS BEEN THE FOCUS FOR
HEAVY RAINFALL THE PAST FEW DAYS...WILL FINALLY DRIFT EAST TONIGHT
THROUGH WEDNESDAY. HIGH PRESSURE WILL DRIFT ACROSS THE UPPER OHIO
VALLEY ON THURSDAY...THEN MOVE OFF THE NEW ENGLAND COAST BY
SUNDAY...IN RESPONSE TO A STRENGTHENING UPPER RIDGE.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
AS OF 1035 PM EDT TUESDAY...
PLANNING TO GO AHEAD AND DROP THE FLASH FLOOD WATCH OVERNIGHT
GIVEN LACK OF COVERAGE AND NOCTURNAL COOLING. HOWEVER SOME
GUIDANCE INCLUDING THE HRRR STILL WANTS TO REDEVELOP HEAVIER SHRA
ESPCLY SOUTH AFTER MIDNIGHT ALONG WHERE THE CURRENT THETA-E GRADIENT
EXISTS. THINK THIS IS OVERDONE AT THIS POINT BUT APPEARS SOME SHRA
WILL FILL BACK IN ALONG THE FOOTHILLS GIVEN LEFTOVER INSTABILITY BUT
LIKELY TOO ISOLATED TO KEEP A BROAD WATCH UP AT THIS POINT. THUS
WILL ONLY KEEP IN HIGH CHANCE POPS SOUTH/EAST OVERNIGHT WITH MENTION
OF BRIEF HEAVY RAIN IN THE HWO. DRIER AIR SEEPING INTO THE WEST
SHOULD KEEP THINGS DRY FROM THE NEW RIVER VALLEY NORTH AND WEST
OVERNIGHT SO TRIMMED POPS A BIT MORE THERE WITH ADDITION OF MORE
DENSE FOG IN SPOTS ESPCLY WHERE ADDED HEAVY RAINFALL OCCURRED THIS
EVENING. MAY NEED A DENSE FOG ADVISORY BY MORNING AS WELL MAINLY
SOUTH AND EAST WHERE DEWPOINTS ARE HIGHER AND DRIER AIR WONT MAKE IT
UNTIL EARLY WED AT BEST. NUDGED DOWN LOW TEMPS A FEW DEGREES WEST
OTRW STAYED CLOSE TO THE PREVIOUS FORECAST.
AS OF 8 PM EDT TUESDAY...
SENT A QUICK UPDATE TO LOWER POPS SIGNIFICANTLY ACROSS THE AREA
GIVEN DIMINISHING ECHOES ALONG THE BLUE RIDGE AND ONLY SCTD STORMS
REMAINING IN THE PIEDMONT AND WEST OF THE NC NRN MOUNTAINS.
APPEARS A BIT LOWER THETA-E AIR ACROSS THE FAR WEST HAS WEAKENED
THE ONGOING CONVERGENCE...WITH OUTFLOW DRIVEN STORMS ACROSS THE
EAST. HOWEVER INSTABILITY REMAINS PRETTY HIGH ESPCLY SOUTH-SE SO
LEAVING IN HIGH CHANCE FOR A FEW MORE HOURS BEFORE LIKELY SEEING A
MORE DIURNALLY DRIVEN REDUCTION IN COVERAGE THIS EVENING PER
WEAKER SUPPORT AND MORE WEST/SW FLOW ALOFT ATTM. APPEARS MOST
AREAS MAY BE PRECIP FREE AROUND MIDNIGHT IF NOT SOONER SIMILAR TO
TO PREVIOUS THINKING SO KEPT IN A SMALL POP MAINLY SE THIRD
OVERNIGHT. MAY ALSO BE ABLE TO DROP THE WATCH EARLY PENDING
COVERAGE OVER THE NEXT COUPLE OF HOURS.
AS OF 249 PM EDT TUESDAY...
SIMILAR TO YESTERDAY AT THIS TIME...SHOWERS AND STORMS HAVE BEEN
SLOW TO DEVELOP THANKS TO CLOUD COVER. BUT WOULDN`T BE SURPRISED
IF RAPID DEVELOPMENT AGAIN OCCURS BY LATE AFTERNOON...WITH OUTFLOW
BOUNDARIES ONLY HELPING MORE STORMS TO POP UP. SPC MESOANALYSIS
CONTINUES TO SHOW INCREASING CAPE/INSTABILITY DESPITE THE CLOUD
COVER. THUNDERSTORMS ALREADY BEGINNING TO LINE UP FROM SW TO NE IN
GRAYSON COUNTY...AND AS THIS CLUSTER MOVES NE MAY BE THE BEGINNING
OF MORE ORGANIZATION MOVING TOWARDS FLOYD AND HARD HIT FRANKLIN
COUNTY. BY DINNERTIME...LOCAL MODELS HAVE AN ORGANIZED TRAINING LINE
RIGHT ALONG THE BLUE RIDGE...AND THE CELLS MAY STAY ANCHORED TO
THE MOUNTAINS CONSIDERING MEAGER LLVL WIND FIELDS AND NIL
SHEAR...BELOW 10 M/S...EVEN THROUGH 3KM AGL. THUS...THE FLASH FLOOD
WATCH STANDS. DESPITE THE RATHER WET SOUNDING...ENOUGH MIDLEVEL
DRY AIR EXISTS SUCH THAT 500 J/KG OF DCAPE IS PRESENT...SO SOME
GUSTY WINDS AND SCATTERED SVR STORMS ARE ALSO POSSIBLE...PER SPC
SLT RISK IN OUR AREA. OF COURSE VERY LOW FFG ESPECIALLY IN HARD
HIT FRANKLIN AND ROCKBRIDGE...UNDER AN INCH AN HOUR...SO IT WILL
NOT TAKE MUCH FOR MORE WATER PROBLEMS CONSIDERING PWATS 120% OF
NORMAL. AGAIN COULD BE LOOKING AT A CRITICAL SITUATION ACROSS THE
HARD HIT AREAS CONSIDERING THESE STORMS HAVE THE POTENTIAL TO PUT
DOWN AN INCH OR TWO IN 30 MINUTES. THE FLASH FLOOD WATCH MAY HAVE
TO BE EXPANDED TOO DEPENDING UPON DEVELOPMENT. LOOKING FOR
FOG WHICH AGAIN COULD BE DENSE AFTER MIDNIGHT...AS STORMS FINALLY
DIE.
WITH THE WEAK BOUNDARY FINALLY MAKING SOME EASTWARD PROGRESS
WEDNESDAY...LLVL WINDS WILL BE DEEPER AND STRONGER FROM A
DOWNSLOPING DIRECTION AS FAR EAST AS THE BLUE RIDGE. ALTHOUGH THIS
USUALLY CREATES ENOUGH SUBSIDENCE TO PRECLUDE PRECIP...CAN`T RULE
OUT AN ISOLATED THUNDERSTORMS OUTSIDE OF SE WEST VA CONSIDERING
SOME INSTABILITY STILL IN PLACE AND DEVELOPING WEAK LEE TROUGH.
LIMITING FACTOR THOUGH WILL BE MIDLEVEL MOISTURE...AS H7 RH GETS
PRETTY DRY BY 18Z/2P WEDNESDAY NEW RIVER VALLEY AND WEST. BEST
OPPORTUNITY FOR SCATTERED STORMS WILL BE ALONG THE SOUTHSIDE
WEDNESDAY...WHERE SOME STORMS AGAIN COULD BE SEVERE...WITH
SOMEWHAT BETTER SHEAR AND UPPER LEVEL WINDS AS A FEW DISTURBANCES
RIDE NE TOWARDS RDU. DRIER AIR AND DOWNSLOPE WARMING...WITH LESS
CLOUDS COMBINED WITH H85 TEMPS AROUND +14C...MEAN THE WARMER SPOTS
SHOULD CROSS 80F SO MAX T WAS RAISED BY SEVERAL DEGREES TO PUT IT
MORE IN LINE WITH MAV/MET MOS.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
AS OF 300 PM EDT TUESDAY...
KEEPING JUST A SLIGHT CHANCE OF SHOWERS/TSRA IN THE FAR SOUTHEAST
WED EVENING AS THE FRONT DEPARTS. WILL SEE CLEARING SKIES WITH WINDS
OUT OF NW AND LIGHT. NOT OUT OF THE QUESTION TO SEE SOME FOG LATE
WED NIGHT IN THE DEEPER VALLEYS.
AMPLIFICATION OF THE 5H TROUGH TAKES PLACE OVER THE SOUTHEAST WITH
MODELS CLOSING OFF A LOW OFF THE COAST BY FRIDAY WITH SHORTWAVE
RIDGING PUSHING INTO THE OHIO VALLEY. NUDGE IN COOLER AIR/DEWPOINTS
WILL BE OCCURRING BEHIND THE FRONT THURSDAY WITH THE SFC HIGH
SHIFTING EWD INTO THE MID ATLANTIC. MOISTURE STAYS MAINLY CONFINED
INTO THE SOUTHEAST THURSDAY BUT ENOUGH EAST FLOW TO ALLOW FOR SOME
ISOLATED MOUNTAIN CONVECTION IN NORTH CAROLINA DURING THE
AFTERNOON/EARLY EVENING.
THU NIGHT-FRIDAY WILL BE MAINLY DRY WITH THE HIGH PRESSURE WEDGING
SW INTO THE MTNS...BUT AGAIN HIGHER MOISTURE STAYS ACROSS THE
SOUTHEAST AND COULD DEFINITELY SHIFT NWD ALONG THE SRN APPALACHIANS
LEADING TO OROGRAPHICALLY INDUCED SHRA/TSRA DURING THE AFTERNOON
FRIDAY. CHANCES STAY SMALL THOUGH.
WENT WITH TEMPS CLOSER TO THE LOCAL MOS THIS PERIOD AS IT HAS
PERFORMED A BIT BETTER THAN THE MET/MAV OVERALL. SHOULD SEE LOWS IN
THE UPPER 40S IN THE MOUNTAINS WED NIGHT TO MID 50S EAST. IT STAYS
SEASONAL INTO FRIDAY WITH HIGHS IN THE 70S AND LOWS IN THE UPPER 40S
TO LOWER 50S.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 1255 PM EDT TUESDAY...
WEEKEND IS LOOKING MAINLY DRY WITH AT OR ABOVE NORMAL TEMPS AS SFC
HIGH WEDGES SOUTHWEST ACROSS THE REGION. CLOUD COVER LOOKS SPARSE
OVERALL...BUT THERE COULD BE STRATUS FORMATION FRI NIGHT WITH SE-E
FLOW ALONG THE BLUE RIDGE. STILL CONFIDENCE NOT HIGH ENOUGH YET TO
GO WITH A BKN-OVC SKY AS HIGH PRESSURE SHOULD CLOSE ENOUGH TO KEEP
THE FLOW LIGHT.
MAKING ADJUSTMENTS HEADING INTO EARLY NEXT WEEK...AS MOST MODELS
AGREE THAT THE UPPER LOW OFF THE SOUTHEAST COAST RETROGRADES TOWARD
FLORIDA BY MONDAY...AND NORTHERN STREAM SHORTWAVE MOVES ACROSS THE
GREAT LAKES. A FRONTAL BOUNDARY APPROACHES THE CENTRAL APPALACHIANS
TUESDAY. MONDAY...MODELS INDICATE ENOUGH ATLANTIC MOISTURE MAY FEED
INTO THE CAROLINAS AND SURGE NWD TOWARD VIRGINIA...THAT WENT WITH
SLIGHT CHANCE OF SHOWERS OR STORMS. BETTER CHANCE ARRIVES BUT STILL
30 POPS TUESDAY WITH SHORTWAVE APPROACHING WITH THE FRONT.
&&
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
AS OF 200 PM EDT WEDNESDAY...
CWA IN BETWEEN MOIST/UNSTABLE AIR MASS TO THE SE AND MORE
STABLE...YET MOIST LOW-LEVEL AIR MASS TO THE NW. BIGGEST PROBLEM FOR
THE MAJORITY OF THE CWA THIS MORNING WILL BE FOG. EXPECT IFR-LIFR
BR/FG AT MANY LOCATIONS ACROSS THE NEW RIVER VALLEY AND WV AREAS
OVERNIGHT. LESS THREAT TOWARD THE PIEDMONT BECAUSE OF EXTENSIVE
HIGH/MID CLOUDS STREAMING NE FROM CONVECTION ACROSS SC/NC.
HOWEVER...STILL EXPECT MVFR BR IN THESE AREAS FOR SEVERAL HOURS
LATER THROUGH EARLY MORNING. FOG SHOULD LIFT ALL AREAS BY 14Z...WITH
GENERALLY SCT-BKN MVFR-LVFR CIGS THROUGH THE MORNING/AFTERNOON
HOURS. FOG POTENTIAL APPEARS TO BE LESS THU MORNING GIVEN SLIGHTLY
DRIER NW FLOW. DEEPER MOISTURE/LIFTING FOCUS FINALLY SHIFTS SE OF
THE CWA BY AFTERNOON...WITH THREAT FOR CONVECTION TODAY GENERALLY
LIMITED TO THE PIEDMONT...HENCE DAN. ON THE OTHER HAND...A WEAK
FRONTAL SYSTEM WILL MOVE INTO WV FROM THE NW DURING THE AFTERNOON.
OROGRAPHIC LIFT/UPSLOPE SHOULD PROVIDE ENOUGH SUPPORT FOR BKN MID
CLOUDS AND AT LEAST ISOLD SHRA...SO HAVE INCLUDED VCSH BLF-LWB LATE
AFTERNOON/EARLY EVENING. DO NOT FEEL THERE WILL BE TSRA WITH
THIS...BUT WILL MONITOR THE THREAT FOR SUCH WITH LATER UPDATES.
WINDS LIGHT/VARIABLE ACROSS THE PIEDMONT TODAY...GENERALLY IN A COL
REGION. WV/NEW RIVER VALLEY TAF SITES SHOULD SEE A LIGHT NW
FLOW...5-7KTS...WITH POTENTIALLY 10KTS ROA DURING AFTERNOON MIXING.
AS OF 700 PM EDT TUESDAY...
SOME IFR CIG/VIS AGAIN MAY OCCUR AT KLWB AS HIGH PRESSURE SLIDES
ACROSS THE OHIO VALLEY WEDNESDAY NIGHT. HIGH PRESSURE ACROSS THE
OHIO VALLEY AND LOW PRESSURE OFF THE COAST WILL COMBINE TO PRODUCE
DEEP BUT RATHER LIGHT EASTERLY UPSLOPE FLOW...WHICH MAY WORK ON
LEFT OVER INSTABILITY KLWB/KBLF ON THURSDAY FOR SOME STORMS. HIGH
PRESSURE STRENGTHENS AND MOVES OFF THE NEW ENGLAND COAST THIS
WEEKEND TAKING ON A WEDGE POSITION...HOWEVER ATTM THIS WEDGE
APPEARS TO BE DRY...ALTHOUGH MORE MOISTURE THAN THE MODELS ARE
FORECASTING COULD PRODUCE SOME MVFR CIGS AT TIMES DURING THE
NIGHTS INTO THE WEEKEND.
&&
.HYDROLOGY...
SOME ADDED SHOWERS MAY OCCUR ALONG THE SOUTHERN BLUE RIDGE AND
FOOTHILLS OVERNIGHT BUT ARE NOT EXPECTED TO BE ENOUGH TO CAUSE
WIDESPREAD FLOODING. THUS HAVE DROPPED THE GOING FLASH FLOOD WATCH
ACROSS THE AREA FOR NOW.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...KM/RAB
NEAR TERM...JH/KM
SHORT TERM...NF
LONG TERM...WP
AVIATION...RAH/WP
HYDROLOGY...JH
AREA FORECAST DISCUSSION...CORRECTED
NWS GOODLAND KS
924 AM MDT WED MAY 16 2012
.UPDATE...
ISSUED AT 911 AM MDT WED MAY 16 2012
FORECAST GENERALLY ON TRACK...WITH ONLY MINOR ADJUSTMENTS TO CATCH
LATEST TRENDS. TD FORECAST ACROSS EASTERN CWA MAY BE TOO HIGH
CONSIDERING LIMITED MOISTURE ADVECTION AND TD VALUES STARTING IN
THE MID TO HIGH 30S. LATEST RUC SEEMED TO HAVE A BETTER HANDLE ON
CURRENT TRENDS SO USED THAT AS A STARTING POINT. OVERALL THIS
RESULTS IN LOWER RH VALUES FURTHER EAST THAN PREVIOUSLY
ADVERTISED...WITH RFW CONDITIONS POSSIBLE FURTHER EAST. QUESTION
REMAINS FUELS ACROSS THE AREA...WITH CURRENT INDICATION THAT FUELS
REMAIN GREEN THE FURTHER EAST IN THE CWA. DISCUSSIONS WITH LOCAL
AUTHORITIES FROM DUNDY COUNTY AND NEAR THE CHEYENNE KANSAS BORDER
INDICATE FAVORABLE FUELS. WITH SHERMAN KS AND CHASE NE ALREADY
UNDER A RED FLAG WARNING I DECIDED TO EXTEND CURRENT RED FLAG
WARNING TO INCLUDE DUNDY AND CHEYENNE BASED ON THESE FUEL
OBSERVATIONS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 244 AM MDT WED MAY 16 2012
0330Z WATER VAPOR INDICATED SHORT WAVE RIDGE IN PLACE ACROSS THE THE
HIGH PLAINS...WITH CLOSED CIRCULATION ASSOCIATED WITH STRONG SHORT
WAVE TROUGH MOVING INTO SOUTHWESTERN UTAH. THIS TROUGH ALREADY
TAKING A MORE SOUTHERLY TRACK THAN PREVIOUSLY EXPECTED AND OVERALL
OBSERVED 12 HOUR HEIGHT FALLS PRETTY WEAK AHEAD OF THIS SYSTEM. 00Z
RAOBS INDICATE A WARM...WELL MIXED AND STABLE AIRMASS WAS IN PLACE
ACROSS THE AREA...WITH VERY DRY AIR/LOW PW`S AT DDC/DNR AND LBF. AT
THE SFC...1021MB SFC HIGH WAS CENTERED OVER NORTHEASTERN NEBRASKA
WITH COLD FRONT FROM APPROX KLAA TO KSLN TO KMCI.
MAIN FORECAST CONCERNS WILL BE FIRE WEATHER AND TEMPS
TODAY...FOLLOWED BY PRECIP CHANCES TONIGHT THROUGH THE WEEKEND.
SHORT TERM...SHORT WAVE TROUGH CURRENTLY MOVING INTO WESTERN UTAH
WILL BE PRIMARY INFLUENCE OF THE WEATHER ACROSS THE CWA AS IT
APPROACHES DURING THE DAY. DRY CONDITIONS ARE EXPECTED THROUGH MUCH
OF THE DAY...BUT SUBSIDENCE WILL DECREASE THROUGH THE MORNING HOURS
AS WEAK LARGE SCALE FORCING ASCENT INCREASES DURING THE AFTERNOON.
ALTHOUGH LIFT DOES INCREASE...LITTLE WITH ATMOSPHERE PROCEEDING
INCOMING TROUGH HAVING VERY LARGE TD DEPRESSIONS...THINK IT WILL BE
DIFFICULT TO HAVE MUCH CHANCE SATURATING/INITIATING ANYTHING UNTIL
VERY LATE IN THE DAY. WHILE BEST LARGE SCALE FORCING APPEARS TO
FAVOR EASTERN COLORADO...DO HAVE A FEW CONCERNS ABOUT CONVECTIVE
INITIATION ALONG RETREATING FRONTAL ZONE IN EASTERN CWA WHERE MORE
INSTABILITY/BETTER MOISTURE PROFILES ARE PRESENT. MAIN ISSUE HERE
WILL BE WHETHER CINH CAN BE OVERCOME AS VALUES ARE EXPECTED TO
REMAIN IN THE 50-150 J/KG RANGE. INITIAL PLAN WAS TO LEAVE OUT...BUT
WANT TO SEE SOME OF THE HIGHER RES DATA BEFORE MAKING A FINAL CALL
HERE. WINDS WILL INCREASE TO AROUND 20KTS IN AREAS SOUTH OF FRONTAL
ZONE. WITH DEEP MIXING EXPECTED TO DROP TDS SHARPLY TO SOUTH OF
FRONT AND CURRENT RFW LOOKS TO BE IN GOOD SHAPE. COULD MAKE AN
ARGUMENT FOR EXTENDING IT TO THE NORTH...BUT WITH RECENT RELATIVE
GREENNESS DATA SHOWING THINGS GREENING UP QUITE A BIT IN CHEYENNE
KS...THINK A WARNING NOT NEEDED AS FUELS MAY NOT BE CRITICAL.
OVERNIGHT LARGE SCALE FORCING FOR ASCENT WILL CONTINUE...ALTHOUGH
MORE SOUTHERLY TRACK OF SYSTEM RESULTS IN MUCH WEAKER AND A MORE
FURTHER WEST/SOUTH AREA OF MAXIMUM ASCENT. WITH THIS IN
MIND...CONFIDENCE MUCH LOWER THAN 24 HOURS AGO WITH RESPECT TO
PRECIP COVERAGE AND OVERALL CHANCES. HAVE DOUBTS THAT ANY STORMS
WILL MAKE IT MUCH FARTHER EAST THAN EASTERN COLORADO GIVEN THE VERY
LIMITED INSTABILITY AND MOISTURE PROFILES AND DO NOT THINK GOING
HIGHER THAN SLIGHT CHANCES AT THIS POINT. SHORT WAVE TROUGH WILL
CONTINUE TO IMPACT THE AREA THROUGH THE DAY THURSDAY...ALTHOUGH Q
VECTOR FIELDS SUGGEST LARGE SCALE FORCING FOR ASCENT WILL BE
MAXIMIZED TO THE SOUTH OF THE AREA. WHILE LARGE SCALE FORCING NOT
ALL THAT GREAT...INSTABILITY VALUES HIGHER AND WITH TEMPS ALOFT
COOLER CINH VALUES WEAKER. MOISTURE RETURN CONCERNS STILL EXIST FOR
PERIOD AS THERE DOES NOT APPEAR TO BE ANY MEANINGFUL MOISTURE
RETURN...SO THINK LIMITING POPS TO THE 20 PERCENT RANGE IN ORDER.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 244 AM MDT WED MAY 16 2012
THURSDAY NIGHT-FRIDAY NIGHT...WEAK SHORT WAVE RIDGING WILL BUILD
OVER THE AREA DURING THE EVENING HOURS...BRINGING AN END TO ANY
PRECIP CHANCES DURING THE OVERNIGHT HOURS. NEXT SHORT WAVE TROUGH
WILL MOVE OVER THE FOUR CORNERS AREA AND INTO COLORADO BY FRIDAY
NIGHT. WHILE LARGE SCALE FORCING FOR ASCENT WITH UPPER TROUGH NOT
EXPECTED TO INFLUENCE THE AREA DIRECTLY UNTIL AROUND 12Z WHEN COLD
FRONT ENTERS CWA...HAVE SOME CONCERNS ABOUT POTENTIAL FOR
THUNDERSTORMS ALONG SFC TROUGH/DRYLINE LATE FRIDAY AFTERNOON AND
EVENING. STRONGEST LOW LEVEL CONVERGENCE EXPECTED TO THE SOUTH OF
SFC LOW CENTERED OVER NORTHEASTERN COLORADO/NEB PANHANDLE. MOISTURE
ADVECTION LOOKS A BIT STRONGER THAN PREVIOUS SYSTEM WITH TDS IN THE
MID 40S TO LOW 50S EXPECTED EAST OF DRY LINE. WHILE THERE IS A SMALL
POTENTIAL FOR STORMS...THINK PROBABILITIES SHOULD REMAIN FAIRLY LOW
FOR THE TIME BEING AS HIGHEST TDS/INSTABILITY WILL BE WELL TO THE
EAST OF BEST SFC CONVERGENCE AND WITH LARGE SCALE FORCING NOT
BECOMING STRONG UNTIL AROUND 12Z THINK SFC FEATURES WILL BE PRIMARY
MEANS FOR ANY CONVECTIVE INITIATION. WINDS INCREASE SHARPLY DURING
THE DAY FRIDAY...ESPECIALLY TO THE EAST OF SFC TROUGH INCREASING
SHARPLY AROUND 00Z. STILL A FAIRLY LARGE DISCREPANCY ON HOW STRONG
WINDS ALOFT WILL BE...BUT THERE LOOKS TO BE AT LEAST SOME POTENTIAL
FOR ADVISORY TYPE WINDS LATE FRIDAY AFTERNOON AND EARLY EVENING.
WINDS SHOULD REMAIN STRONG/GUSTY DURING THE OVERNIGHT HOURS AHEAD OF
COLD FRONT KEEPING LOWS MUCH WARMER THAN THE PAST FEW DAYS WITH MANY
LOCATIONS SEEING LOWS STAY IN THE 60S.
A STRONG COLD FRONT WILL MOVE THROUGH THE REGION SATURDAY MORNING
AHEAD OF A SHORTWAVE TROUGH THAT WILL MOVE THROUGH THE CENTRAL
ROCKIES AND INTO KANSAS BEFORE SWINGING UP INTO NEBRASKA BY SATURDAY
EVENING. PRECIPITATION CHANCES WILL INCREASE AS THE FRONT MOVES
THROUGH THE REGION...WITH BEST CHANCES ACROSS THE NORTHERN HALF OF
THE CWA. DRY SLOT APPEARS TO DEVELOP AND WILL KEEP PRECIPITATION
CHANCES LOW ACROSS PARTS OF SOUTHEAST COLORADO AND SOUTHWEST KANSAS.
COOLER AIR WILL MOVE IN BEHIND THE FRONT WITH A GRADUAL WARMING
THROUGH NEXT WEEK. ANOTHER SHORTWAVE TROUGH WILL MOVE THROUGH THE
REGION ON SUNDAY...BUT WITH HIGHER SURFACE DEWPOINTS EXPECTED TO BE
MUCH FURTHER EASTWARD ACROSS EASTERN KANSAS...AM NOT EXPECTING
THUNDERSTORMS TO DEVELOP SUNDAY AFTERNOON. BY EARLY NEXT
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 536 AM MDT WED MAY 16 2012
VFR CONDITIONS EXPECTED FOR THE NEXT 24 HOURS AS UPPER LEVEL
DISTURBANCE APPROACHES FROM THE WEST. PERIOD OF LLWS AT GLD SHOULD
END QUICKLY THIS MORNING AS SFC WINDS INCREASE WITH HEATING.
SOUTHEASTERLY WINDS WILL GRADUALLY SHIFT TO THE SOUTH AND INCREASE
TO AROUND 20KTS...MAINLY AFTER 17Z. THERE IS A SMALL CHANCE FOR
THUNDERSTORMS BTWN 00Z AND 06Z...BUT THESE SHOULD REMAIN WELL TO
THE WEST OF TAF SITES.
&&
.FIRE WEATHER...
ISSUED AT 236 AM MDT WED MAY 16 2012
CRITICAL FIRE WEATHER CONDITIONS EXPECTED TODAY AS A DEVELOPING
SURFACE TROUGH BRINGS SOUTHERLY WINDS OF 15 TO 25 MPH TO THE AREA
AND AFTERNOON HUMIDITIES FALL TO LESS THAN 15 PERCENT ACROSS MUCH
OF THE AREA. BASED ON LATEST FUEL REPORTS AND AVAILABLE SATELLITE
GREENESS DATA...IT APPEARS THAT WITH THE EXCEPTION OF PORTIONS OF
EASTERN COLORADO AND ADJACENT AREAS OF NORTHWEST KANSAS WIDESPREAD
CRITICAL FUELS ARE NOT AVAILABLE.
AFTERNOON HUMIDITIES WILL FALL TO THE 10 TO 20 PERCENT RANGE EACH
AFTERNOON THROUGH FRIDAY. WINDS ARE EXPECTED TO REMAIN CRITICAL
VALUES ON THURSDAY...BUT WILL INCREASE THROUGH THE DAY FRIDAY.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...RED FLAG WARNING UNTIL 8 PM MDT /9 PM CDT/ THIS EVENING FOR
KSZ001-013-027.
CO...RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ252>254.
NE...RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR NEZ079.
&&
$$
UPDATE...DR
SHORT TERM...JRM
LONG TERM...JRM/PM
AVIATION...JRM
FIRE WEATHER...JRM
AREA FORECAST DISCUSSION
NWS GOODLAND KS
912 AM MDT WED MAY 16 2012
.UPDATE...
ISSUED AT 911 AM MDT WED MAY 16 2012
FORECAST GENERALLY ON TRACK...WITH ONLY MINOR ADJUSTMENTS TO CATCH
LATEST TRENDS. TD FORECAST ACROSS EASTERN CWA MAY BE TOO HIGH
CONSIDERING LIMITED MOISTURE ADVECTION AND TD VALUES STARTING IN
THE MID TO HIGH 30S. LATEST RUC SEEMED TO HAVE A BETTER HANDLE ON
CURRENT TRENDS SO USED THAT AS A STARTING POINT. OVERALL THIS
RESULTS IN LOWER RH VALUES FURTHER EAST THAN PREVIOUSLY
ADVERTISED...WITH RFW CONDITIONS POSSIBLE FURTHER EAST. QUESTION
REMAINS FUELS ACROSS THE AREA...WITH CURRENT INDICATION THAT FUELS
REMAIN GREEN THE FURTHER EAST IN THE CWA. DISCUSSIONS WITH LOCAL
AUTHORITIES FROM DUN DY COUNTY AND NEAR THE CHEYENNE KANSAS BORDER
INDICATE FAVORABLE FUELS. WITH SHERMAN KS AND CHASE NE ALREADY
UNDER A RED FLAG WARNING I DECIDED TO EXTEND CURRENT RED FLAG
WARNING TO INCLUDE DUN DY AND CHEYENNE BASED ON THESE FUEL
OBSERVATIONS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 244 AM MDT WED MAY 16 2012
0330Z WATER VAPOR INDICATED SHORT WAVE RIDGE IN PLACE ACROSS THE THE
HIGH PLAINS...WITH CLOSED CIRCULATION ASSOCIATED WITH STRONG SHORT
WAVE TROUGH MOVING INTO SOUTHWESTERN UTAH. THIS TROUGH ALREADY
TAKING A MORE SOUTHERLY TRACK THAN PREVIOUSLY EXPECTED AND OVERALL
OBSERVED 12 HOUR HEIGHT FALLS PRETTY WEAK AHEAD OF THIS SYSTEM. 00Z
RAOBS INDICATE A WARM...WELL MIXED AND STABLE AIRMASS WAS IN PLACE
ACROSS THE AREA...WITH VERY DRY AIR/LOW PW`S AT DDC/DNR AND LBF. AT
THE SFC...1021MB SFC HIGH WAS CENTERED OVER NORTHEASTERN NEBRASKA
WITH COLD FRONT FROM APPROX KLAA TO KSLN TO KMCI.
MAIN FORECAST CONCERNS WILL BE FIRE WEATHER AND TEMPS
TODAY...FOLLOWED BY PRECIP CHANCES TONIGHT THROUGH THE WEEKEND.
SHORT TERM...SHORT WAVE TROUGH CURRENTLY MOVING INTO WESTERN UTAH
WILL BE PRIMARY INFLUENCE OF THE WEATHER ACROSS THE CWA AS IT
APPROACHES DURING THE DAY. DRY CONDITIONS ARE EXPECTED THROUGH MUCH
OF THE DAY...BUT SUBSIDENCE WILL DECREASE THROUGH THE MORNING HOURS
AS WEAK LARGE SCALE FORCING ASCENT INCREASES DURING THE AFTERNOON.
ALTHOUGH LIFT DOES INCREASE...LITTLE WITH ATMOSPHERE PROCEEDING
INCOMING TROUGH HAVING VERY LARGE TD DEPRESSIONS...THINK IT WILL BE
DIFFICULT TO HAVE MUCH CHANCE SATURATING/INITIATING ANYTHING UNTIL
VERY LATE IN THE DAY. WHILE BEST LARGE SCALE FORCING APPEARS TO
FAVOR EASTERN COLORADO...DO HAVE A FEW CONCERNS ABOUT CONVECTIVE
INITIATION ALONG RETREATING FRONTAL ZONE IN EASTERN CWA WHERE MORE
INSTABILITY/BETTER MOISTURE PROFILES ARE PRESENT. MAIN ISSUE HERE
WILL BE WHETHER CINH CAN BE OVERCOME AS VALUES ARE EXPECTED TO
REMAIN IN THE 50-150 J/KG RANGE. INITIAL PLAN WAS TO LEAVE OUT...BUT
WANT TO SEE SOME OF THE HIGHER RES DATA BEFORE MAKING A FINAL CALL
HERE. WINDS WILL INCREASE TO AROUND 20KTS IN AREAS SOUTH OF FRONTAL
ZONE. WITH DEEP MIXING EXPECTED TO DROP TDS SHARPLY TO SOUTH OF
FRONT AND CURRENT RFW LOOKS TO BE IN GOOD SHAPE. COULD MAKE AN
ARGUMENT FOR EXTENDING IT TO THE NORTH...BUT WITH RECENT RELATIVE
GREENNESS DATA SHOWING THINGS GREENING UP QUITE A BIT IN CHEYENNE
KS...THINK A WARNING NOT NEEDED AS FUELS MAY NOT BE CRITICAL.
OVERNIGHT LARGE SCALE FORCING FOR ASCENT WILL CONTINUE...ALTHOUGH
MORE SOUTHERLY TRACK OF SYSTEM RESULTS IN MUCH WEAKER AND A MORE
FURTHER WEST/SOUTH AREA OF MAXIMUM ASCENT. WITH THIS IN
MIND...CONFIDENCE MUCH LOWER THAN 24 HOURS AGO WITH RESPECT TO
PRECIP COVERAGE AND OVERALL CHANCES. HAVE DOUBTS THAT ANY STORMS
WILL MAKE IT MUCH FARTHER EAST THAN EASTERN COLORADO GIVEN THE VERY
LIMITED INSTABILITY AND MOISTURE PROFILES AND DO NOT THINK GOING
HIGHER THAN SLIGHT CHANCES AT THIS POINT. SHORT WAVE TROUGH WILL
CONTINUE TO IMPACT THE AREA THROUGH THE DAY THURSDAY...ALTHOUGH Q
VECTOR FIELDS SUGGEST LARGE SCALE FORCING FOR ASCENT WILL BE
MAXIMIZED TO THE SOUTH OF THE AREA. WHILE LARGE SCALE FORCING NOT
ALL THAT GREAT...INSTABILITY VALUES HIGHER AND WITH TEMPS ALOFT
COOLER CINH VALUES WEAKER. MOISTURE RETURN CONCERNS STILL EXIST FOR
PERIOD AS THERE DOES NOT APPEAR TO BE ANY MEANINGFUL MOISTURE
RETURN...SO THINK LIMITING POPS TO THE 20 PERCENT RANGE IN ORDER.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 244 AM MDT WED MAY 16 2012
THURSDAY NIGHT-FRIDAY NIGHT...WEAK SHORT WAVE RIDGING WILL BUILD
OVER THE AREA DURING THE EVENING HOURS...BRINGING AN END TO ANY
PRECIP CHANCES DURING THE OVERNIGHT HOURS. NEXT SHORT WAVE TROUGH
WILL MOVE OVER THE FOUR CORNERS AREA AND INTO COLORADO BY FRIDAY
NIGHT. WHILE LARGE SCALE FORCING FOR ASCENT WITH UPPER TROUGH NOT
EXPECTED TO INFLUENCE THE AREA DIRECTLY UNTIL AROUND 12Z WHEN COLD
FRONT ENTERS CWA...HAVE SOME CONCERNS ABOUT POTENTIAL FOR
THUNDERSTORMS ALONG SFC TROUGH/DRYLINE LATE FRIDAY AFTERNOON AND
EVENING. STRONGEST LOW LEVEL CONVERGENCE EXPECTED TO THE SOUTH OF
SFC LOW CENTERED OVER NORTHEASTERN COLORADO/NEB PANHANDLE. MOISTURE
ADVECTION LOOKS A BIT STRONGER THAN PREVIOUS SYSTEM WITH TDS IN THE
MID 40S TO LOW 50S EXPECTED EAST OF DRY LINE. WHILE THERE IS A SMALL
POTENTIAL FOR STORMS...THINK PROBABILITIES SHOULD REMAIN FAIRLY LOW
FOR THE TIME BEING AS HIGHEST TDS/INSTABILITY WILL BE WELL TO THE
EAST OF BEST SFC CONVERGENCE AND WITH LARGE SCALE FORCING NOT
BECOMING STRONG UNTIL AROUND 12Z THINK SFC FEATURES WILL BE PRIMARY
MEANS FOR ANY CONVECTIVE INITIATION. WINDS INCREASE SHARPLY DURING
THE DAY FRIDAY...ESPECIALLY TO THE EAST OF SFC TROUGH INCREASING
SHARPLY AROUND 00Z. STILL A FAIRLY LARGE DISCREPANCY ON HOW STRONG
WINDS ALOFT WILL BE...BUT THERE LOOKS TO BE AT LEAST SOME POTENTIAL
FOR ADVISORY TYPE WINDS LATE FRIDAY AFTERNOON AND EARLY EVENING.
WINDS SHOULD REMAIN STRONG/GUSTY DURING THE OVERNIGHT HOURS AHEAD OF
COLD FRONT KEEPING LOWS MUCH WARMER THAN THE PAST FEW DAYS WITH MANY
LOCATIONS SEEING LOWS STAY IN THE 60S.
A STRONG COLD FRONT WILL MOVE THROUGH THE REGION SATURDAY MORNING
AHEAD OF A SHORTWAVE TROUGH THAT WILL MOVE THROUGH THE CENTRAL
ROCKIES AND INTO KANSAS BEFORE SWINGING UP INTO NEBRASKA BY SATURDAY
EVENING. PRECIPITATION CHANCES WILL INCREASE AS THE FRONT MOVES
THROUGH THE REGION...WITH BEST CHANCES ACROSS THE NORTHERN HALF OF
THE CWA. DRY SLOT APPEARS TO DEVELOP AND WILL KEEP PRECIPITATION
CHANCES LOW ACROSS PARTS OF SOUTHEAST COLORADO AND SOUTHWEST KANSAS.
COOLER AIR WILL MOVE IN BEHIND THE FRONT WITH A GRADUAL WARMING
THROUGH NEXT WEEK. ANOTHER SHORTWAVE TROUGH WILL MOVE THROUGH THE
REGION ON SUNDAY...BUT WITH HIGHER SURFACE DEWPOINTS EXPECTED TO BE
MUCH FURTHER EASTWARD ACROSS EASTERN KANSAS...AM NOT EXPECTING
THUNDERSTORMS TO DEVELOP SUNDAY AFTERNOON. BY EARLY NEXT
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 536 AM MDT WED MAY 16 2012
VFR CONDITIONS EXPECTED FOR THE NEXT 24 HOURS AS UPPER LEVEL
DISTURBANCE APPROACHES FROM THE WEST. PERIOD OF LLWS AT GLD SHOULD
END QUICKLY THIS MORNING AS SFC WINDS INCREASE WITH HEATING.
SOUTHEASTERLY WINDS WILL GRADUALLY SHIFT TO THE SOUTH AND INCREASE
TO AROUND 20KTS...MAINLY AFTER 17Z. THERE IS A SMALL CHANCE FOR
THUNDERSTORMS BTWN 00Z AND 06Z...BUT THESE SHOULD REMAIN WELL TO
THE WEST OF TAF SITES.
&&
.FIRE WEATHER...
ISSUED AT 236 AM MDT WED MAY 16 2012
CRITICAL FIRE WEATHER CONDITIONS EXPECTED TODAY AS A DEVELOPING
SURFACE TROUGH BRINGS SOUTHERLY WINDS OF 15 TO 25 MPH TO THE AREA
AND AFTERNOON HUMIDITIES FALL TO LESS THAN 15 PERCENT ACROSS MUCH
OF THE AREA. BASED ON LATEST FUEL REPORTS AND AVAILABLE SATELLITE
GREENESS DATA...IT APPEARS THAT WITH THE EXCEPTION OF PORTIONS OF
EASTERN COLORADO AND ADJACENT AREAS OF NORTHWEST KANSAS WIDESPREAD
CRITICAL FUELS ARE NOT AVAILABLE.
AFTERNOON HUMIDITIES WILL FALL TO THE 10 TO 20 PERCENT RANGE EACH
AFTERNOON THROUGH FRIDAY. WINDS ARE EXPECTED TO REMAIN CRITICAL
VALUES ON THURSDAY...BUT WILL INCREASE THROUGH THE DAY FRIDAY.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...RED FLAG WARNING UNTIL 8 PM MDT /9 PM CDT/ THIS EVENING FOR
KSZ001-013-027.
CO...RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ252>254.
NE...RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR NEZ079.
&&
$$
UPDATE...DR
SHORT TERM...JRM
LONG TERM...JRM/PM
AVIATION...JRM
FIRE WEATHER...JRM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
628 AM EDT WED MAY 16 2012
.SYNOPSIS...
ISSUED AT 518 AM EDT WED MAY 16 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE FROM
THE ROCKIES INTO SASK AND A DOWNSTREAM TROUGH FROM HUDSON BAY INTO
THE CNTRL GREAT LAKES RESULTING IN NW FLOW THROUGH UPPER MI. AT THE
SFC...HIGH PRES FROM MANITOBA INTO WRN MN WAS BUILDING INTO THE WRN
GREAT LAKES. SUBSIDENCE AND DRY ADVECTION IN THE WAKE OF THE MID
LEVEL TROUGH HAS BROUGHT CLEAR SKIES TO THE AREA ALONG WITH
DIMINISHING WINDS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 518 AM EDT WED MAY 16 2012
TODAY...SUNSHINE AND MIXING IN THE VERY DRY AIRMASS (PWAT VALUES
DOWN TO NEAR 0.25 INCH) OVER THE AREA WILL BOOST TEMPS INTO THE
LOWER TO MID 60S BUT PUSH DEWPOINTS DOWN TO NEAR 20 OVER INLAND
LOCATIONS THIS AFTERNOON. THIS WILL RESULT IN RH VALUES IN THE 20 TO
25 PCT RANGE. FORTUNATELY WINDS WILL BE RELATIVELY LIGHT...ONLY
INCREASING INTO THE 10 TO 15 MPH RANGE THIS AFTERNOON.
TONIGHT...AS THE MID LEVEL RIDGE EDGES TO THE EAST...DOWNSTREAM WAA
AND 300K-305K ISENTROPIC LIFT WILL BRING AN INCREASE IN MID LEVEL
CLOUDS FROM NW ONTARIO INTO UPPER MI. HOWEVER...LIGHT WINDS AND
MAINLY CLEAR SKIES TIL LATE NIGHT OVER THE EAST WILL RESULT IN
DECENT RADIATIONAL COOLING WITH TEMPS FALLING INTO THE LOWER 30S.
A FROST ADVY MAY BE NEEDED FOR THE INTERIOR EAST HALF...ESPECIALLY
IF THERE IS A TREND TOWARD LATER INCREASE IN CLOUDS.
THURSDAY...EXPECT THE POSITION OF THE 850 MB WARM FRONT AND GREATER
LOW LEVEL THETA-E ADVECTION...PER NAM/GFS/ECMWF...TO REMAIN FAR
ENOUGH TO THE SOUTH AND WEST TO KEEP BEST PCPN CHANCES OVER NRN
MN AND NRN WI. HOWEVER...SOME SHRA MAY BRUSH MAINLY THE SW PORTION
OF THE CWA. CLOUD COVER SHOULD BE THICK ENOUGH TO KEEP TEMPS INTO
THE MID TO UPPER 60S...EVEN AS 850 MB TEMPS CLIMB INTO THE 7C TO 10C
RANGE.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 518 AM EDT WED MAY 16 2012
NAM STARTS OFF WITH A 500 MB TROUGH OVER THE WESTERN U.S. AND
SHORTWAVE IN THE CENTRAL PLAINS 00Z FRI WITH RIDGING INTO THE UPPER
MISSISSIPPI RIVER VALLEY AND TROUGHING IN THE SERN U.S. AND ALSO IN
NEW ENGLAND. UPPER LEVEL RIDGING BUILDS INTO THE UPPER GREAT LAKES
THIS PERIOD.
NAM BRINGS THIS SHORTWAVE NORTHEAST FRIDAY WITH 850-500 MB Q-VECTOR
CONVERGENCE AND DEEPER MOISTURE MOVING THROUGH THE AREA BEFORE BOTH
GET PUSHED NORTH FRIDAY NIGHT. NAM ALSO SHOWS SOME ISENTROPIC LIFT
AND LIMITED MOISTURE THU NIGHT WITH A WARM FRONT MOVING THROUGH THE
AREA BEFORE THE LIFT AND MOISTURE PUSH NORTH ON FRIDAY. GFS SHOWS
ABOUT THE SAME THING FOR ISENTROPIC LIFT ON I300K-I310K SURFACES AND
MOISTURE THU NIGHT INTO FRI. GFS AND ECMWF ALSO SHOW 850-500 MB
Q-VECTOR CONVERGENCE OVER THE AREA THROUGH 12Z SAT. WILL PUT IN
CHANCE TO SLIGHT CHANCE POPS FOR THIS WARM FRONT THU NIGHT THROUGH
FRIDAY NIGHT ACROSS THE AREA. BEST CHANCES FOR PCPN WILL BE ACROSS
THE WEST AND LOWEST IN THE EAST AWAY FROM THE BETTER MOISTURE AND
DYNAMICS. DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST FOR
TEMPERATURES.
IN THE EXTENDED...ECMWF SHOWS A 500 MB RIDGE OVER THE UPPER GREAT
LAKES WITH TROUGHING IN THE WESTERN U.S. 12Z WITH A TROUGH IN THE
EASTERN U.S. AND A WEAK CLOSED 500 MB LOW OVER THE SERN U.S. PATTERN
CHANGES LITTLE 12Z SUNDAY BEFORE THE TROUGH IN THE WESTERN U.S.
MOVES INTO THE UPPER GREAT LAKES SUN NIGHT THROUGH TUE. GFS SHOWS
ABOUT THE SAME THING THROUGH SUNDAY. WHAT THIS WILL MEAN IS A VERY
WARM PERIOD AT THE START OF THE WEEKEND...THEN A COOL DOWN INTO
EARLY NEXT WEEK. TEMPERATURES WILL STILL BE AT OR ABOVE NORMAL
THOUGH. WITH THE UPPER LEVEL TROUGH REMAINING INTO TUE...AFTER
CHANCE TO LIKELY POPS ON SUNDAY WITH THE COLD FRONT...SLIGHT CHANCE
POPS FOR MONDAY INTO TUESDAY STILL SEEM WARRANTED. DID BUMP HIGHS UP
A BIT ON SATURDAY AS PLENTY OF SUNSHINE AND 850 MB TEMPERATURES TO
14C TO 16C...THIS WOULD GIVE HIGHS IN THE LOWER TO MID 80S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 628 AM EDT WED MAY 16 2012
ALTHOUGH THERE WL BE A GRADUAL INCRS IN MID AND HI CLDS
LATER...EXPECT VFR CONDITIONS AND LIGHT WINDS THIS FCST PERIOD WITH
DRY HI PRES DOMINATING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 518 AM EDT WED MAY 16 2012
WINDS WILL BE BELOW 25 KNOTS THROUGH THE PERIOD. A HIGH PRESSURE
RIDGE WILL BUILD INTO THE REGION TODAY THROUGH THURSDAY. A LOW
PRESSURE TROUGH WILL APPROACH FROM THE PLAINS AND PUSH A WARM FRONT
ACROSS THE AREA THURSDAY NIGHT INTO FRIDAY. A COLD FRONT WILL MOVE
THROUGH THE UPPER GREAT LAKES ON SUNDAY WITH COOLER HIGH PRESSURE
BUILDING BACK IN FOR EARLY NEXT WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...07
AVIATION...07
MARINE...07
AREA FORECAST DISCUSSION
NWS GLASGOW MT
916 AM MDT WED MAY 16 2012
.SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH FRIDAY...
ONLY MINOR TWEAK TO FORECAST FOR THE MORNING UPDATE. INCREASED
CLOUD COVER A LITTLE BIT TO ACCOUNT FOR SOME CUMULUS AND STRATUS
OVER MUCH OF THE AREA. QUITE WARM TODAY. HRRR MODEL SHOWS SOME
THUNDERSHOWERS INITIATING OVER THE ROCKY MOUNTAINS THIS AFTERNOON.
SOME OF THESE SHOWERS MAY APPROACH THE AREA THIS EVENING OR
TONIGHT...HOWEVER...FORCING FROM SURFACE HEATING WILL BE IN
DECLINE BY THEN AND STORMS ARE EXPECTED TO DIE OUT BEFORE REACHING
OUR AREA. CHANCES FOR PRECIPITATION ARE MUCH BETTER LATE THURSDAY
INTO FRIDAY AS TROUGH PASSES OVER THE AREA. MARTIN
PREVIOUS DISCUSSION...
UPPER RIDGE PROGRESSING EASTWARD WILL BRING CONTINUED DRY YET
WARMER WEATHER TO NORTHEAST MONTANA TODAY. LEE TROF WILL ALSO MOVE
EASTWARD SWITCHING THE LOW LEVEL FLOW FROM SOUTHEAST TO WEST. WEAK
CLOSED LOW MOVING ACROSS WYOMING WILL PUSH SOME MOISTURE AND
INSTABILITY INTO SOUTHERN MONTANA...WILL HELP DEVELOP
THUNDERSTORMS OVER THE HIGHER TERRAIN OF SOUTH CENTRAL MONTANA
LATE THIS AFTERNOON.
COLD FRONT MOVES THROUGH THE STATE LATE TONIGHT AND AS UPPER FLOW
TURNS SOUTHWEST...MOISTURE WILL BE INCREASING. BEST PUSH OF
MOISTURE AND INSTABILITY INTO MONTANA NOT EXPECT TO OCCUR UNTIL
THURSDAY NIGHT AS UPPER TROF DIGS ACROSS THE GREAT BASIN. COOLER
AND WETTER WEATHER WILL CONTINUE INTO FRIDAY. EBERT
.LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY...
AN UPPER PATTERN OF TROUGH...THEN RIDGE...THEN TROUGH. MODELS AGREE
WITH THIS...SO WEATHER IS STRAIGHTFORWARD WITH A THREAT OF SHOWERS
AND SOMEWHAT COOL WEATHER BEGINNING AND ENDING OF THE PERIOD...AND
A SUNNY AND WARM PERIOD IN THE MIDDLE.
A VERY ELONGATED UPPER TROUGH MOVES ACROSS THE AREA SATURDAY.
MOST SHOWER ACTIVITY IS FRI NIGHT THOUGH AS MODELS INDICATE
DOWNSLOPE DRYING ARRIVING SATURDAY. COOL TEMPS WITH GFS AND CMC
GEM INDICATING 850MB TEMPS AS LOW AS 2C IN OUR NW SAT MORN...AND WITH
COOL ADVECTION CAUSING SOMEWHAT WINDY WEATHER AS WELL.
THE UPPER RIDGE THEN BRINGS CLEAR SKIES AND A STRONG WARMING TREND
FOR SUNDAY/MONDAY. THICKNESSES RISE TO THE LOWER 570S DM...
INDICATING 80S FOR HIGHS.
THE END OF THE PERIOD WITH ANOTHER APPROACHING TROUGH IS EXPECTEDLY
FUZZY ON DETAILS...LOCATION OF SHOWER THREATS AND DRY
DOWNSLOPING...BUT REASONABLE TO HAVE SLIGHT CHANCE POPS FOR AT
LEAST 2 OR 3 FORECAST PERIODS...AND ALSO TO START A COOLING TREND.
SIMONSEN
&&
.AVIATION...
VFR WITH ONLY SCATTERED CLOUDS ABOVE 10K FT AGL. LIGHT SOUTHEAST
WINDS WILL SLOWLY VEER AROUND TO THE WEST DURING THE AFTERNOON.
HICKS/SIMONSEN
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1035 AM EDT WED MAY 16 2012
.SYNOPSIS...
A SLOW MOVING COLD FRONT WILL BRING SHOWERS AND THUNDERSTORMS AGAIN
TODAY...WITH SOME OF THESE PRODUCING VERY HEAVY RAINFALL. SHOWERS
AND THUNDERSTORMS ARE POSSIBLE AGAIN THURSDAY AS AN APPROACHING COLD
FRONT FINALLY PUSHES OFFSHORE. BUILDING HIGH PRESSURE WILL BRING
DRIER AND MORE SEASONABLE WEATHER FRIDAY THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 10:30 AM WEDNESDAY...ANALYSIS OF MORNING SOUNDINGS CONFIRM
EARLIER HYPOTHESIS THAT TODAY WILL FEATURE ANOTHER ROUND OF
DIURNALLY-DRIVEN CONVECTION. MOIST SOUTHWESTERLY FLOW WILL REMAIN
IN PLACE WITH P/W VALUES OF AROUND 1.50 INCHES AND DEWPOINTS WELL
IN THE 60S. MODEL SOUNDINGS DEVELOP MODERATE INSTABILITY WITH
STEEP LAPSE RATES ACROSS THE AREA THIS AFTERNOON. PEAK
DESTABILIZATION WILL THUS BE THIS AFTERNOON...WHEN THE GREATEST
THREAT OF STRONG CONVECTION WILL BE. UNTIL THEN...EXPECT INITIAL
CONVECTION TO FIRE UP ALONG A WEAK SEA BREEZE BOUNDARY LATE THIS
MORNING AND EARLY AFTERNOON. HRRR MODEL DID FAIRLY WELL DEPICTING
THIS YESTERDAY...AND IS GOING FOR A REPEAT PERFORMANCE TODAY.
PREVIOUS DISCUSSION FOLLOWS:
INGREDIENTS COALESCING FOR ANOTHER ROUND OF DIURNAL THUNDERSTORMS
AS HEATING DESTABILIZES A MOISTURE RICH COLUMN. WEAK OUTFLOW
BOUNDARIES SNAKING ACROSS THE REGION EARLY THIS MORNING WILL
PRODUCE ISOLATED HEAVY THUNDERSHOWERS EVEN PRIOR TO DIURNAL
WARMING. THE SEA BREEZE BOUNDARY WILL PROVIDE A FOCUS FOR A BROKEN
LINE OF THUNDERSTORMS TO LIGHT UP BY EARLY AFTERNOON ACROSS OUR
COASTAL INTERIOR. UPPER WINDS MAY PUSH THE CONVECTION BACK TOWARD
THE COAST IN THE LATE AFTERNOON AND EVENING.
PRECIPITABLE WATER VALUES BETWEEN 1.3-1.5 ACROSS THE REGION AND
DEWPOINTS OF 66-71...WILL INTERACT WITH SHARPENING LOW-LEVEL LAPSE
RATES BY MID AFTERNOON TO PRODUCE AN ISOLATED POTENTIAL FOR STRONG
WIND GUSTS OR DAMAGING WINDS.
PLENTIFUL CLOUDS WILL KEEP MAX TEMPS HELD IN THE LOWER TO MIDDLE
80S TODAY. A COLD FRONT WILL EXIT THE MOUNTAINS TODAY AND MOVE TO
THE COAST LATE TONIGHT INTO DAYBREAK THURSDAY. FOR THIS REASON
MENTIONABLE POP VALUES WERE RETAINED TROUGH THE OVERNIGHT PERIOD.
MINIMUM TEMPS AS A RESULT SHOULD BE JUST A DEGREE OR TWO COOLER
THAN THE LAST FEW MORNINGS.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 AM WEDNESDAY...SLIGHTLY SLOWER EVOLUTION AS DEPICTED IN
GUIDANCE NOW SUGGESTS THAT THURSDAY WILL BE THE TRANSITION DAY AS
COLD FRONT...FINALLY...PUSHES OFFSHORE. PERSISTENT UPPER TROUGH
NEVER QUITE MOVES AWAY HOWEVER...AND INSTEAD ADOPTS AN ORIENTATION
MORE WSW-TO-ENE ACROSS THE SOUTHEAST AND BACK TOWARDS THE MS VLY. AT
THE SAME TIME...AN ARC OF RIDGING DEVELOPS NORTH OF THIS FEATURE
FROM THE OH VLY INTO THE MID-ATLANTIC. WITH WEAK OVERALL FORCING AND
A MORE ZONALLY DRIVEN SETUP AT 500MB...FEATURES WILL CONTINUE TO BE
QUITE SLOW TO MOVE...KEEPING AT LEAST THE POTENTIAL FOR UNSETTLED
WEATHER THROUGH THE PERIOD.
AT THE SURFACE...A COLD FRONT WILL DROP SOUTH THROUGH THE CWA EARLY
THURSDAY...BUT IS NOW PROGGED TO HANG UP AND STALL ACROSS SOUTHERN
AND COASTAL PORTIONS OF THE CWA. THIS WILL AGAIN SERVE AS A FOCUS
FOR CONVECTION...ALTHOUGH POSSIBLY SPARING INLAND LOCATIONS THAT
HAVE SEEN SIGNIFICANT RAINFALL THE PAST FEW DAYS. WILL CARRY CHC POP
THURSDAY ALONG THE COAST AND SC ZONES...WITH SCHC INLAND/NC
COUNTIES. THIS FRONT WILL PUSH ONLY SLIGHTLY FURTHER SOUTH FRIDAY AS
SURFACE HIGH RIDGES DOWN FROM THE NORTH. EVEN THOUGH THE FRONT WILL
REMAIN INVOF THIS AREA...MUCH DRIER AIR NOTED IN FORECAST SOUNDINGS
SUGGESTS THAT FRIDAY WILL BE A DRY DAY SO WILL KEEP POP SILENT
FRIDAY.
TEMPS WILL REMAIN AROUND CLIMO FOR HIGHS AND LOWS THROUGH THE
PERIOD...A FEW DEGREES EITHER SIDE OF 80 AND 60.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 300 AM WEDNESDAY...GUIDANCE COMING INTO BETTER AGREEMENT FOR
THE WKND WITH A RESIDUAL E-W ORIENTED 500MB TROUGH PERSISTING ACROSS
THE SOUTHEAST...WHILE A RIDGE DEVELOPS NORTH OF THIS FROM THE OH VLY
INTO THE MID ATLANTIC. AT THE SURFACE...A STALLED STATIONARY FRONT
WILL BE DRAPED JUST OFF THE COAST AND BACK INTO NORTHERN
FLORIDA...WHILE A RIDGE OF HIGH PRESSURE PUSHES NE DOWN THE COAST.
EVEN WITH THE FRONT REMAINING NEAR THE AREA...EXPECT THE WKND TO BE
DRY. THE RIDGE OF HIGH PRESSURE WILL PROMOTE A SUBTLE SUBSIDENCE
INVERSION NEAR THE SURFACE WHILE DRIER AIR REMAINS IN THE MID
LEVELS. WILL KEEP POP JUST BELOW THRESHOLD NEAR THE COAST TO ACCOUNT
FOR THE BOUNDARY OFFSHORE...BUT EXPECT NO SHOWERS THROUGH THE WKND.
AS SURFACE HIGH DRIFTS OFF THE NEW ENGLAND COAST MON/TUE...SURFACE
FLOW BECOMES MORE EASTERLY WHICH INCREASES MOISTURE ADVECTION INTO
THE COLUMN. ADDITIONALLY...THICKNESSES BEGIN TO RETURN TO MORE
SEASONABLE LEVELS AS PERSISTENT TROUGHING FINALLY BEGINS TO ERODE.
THIS COULD ALLOW FOR DIURNAL SHOWERS TO RETURN MON/TUE AND WILL
CARRY SCHC BEING SO FAR OUT.
TEMPS THROUGH THE PERIOD WILL BE AROUND CLIMO FOR MAXES AND
MINS...BECOMING SLIGHTLY ABOVE AT THE END OF THE PERIOD.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
AS OF 12Z...JUICY AIRMASS IN PLACE WITH CONVECTION JUST OFFSHORE.
LOOK FOR A RATHER UNEVENTFUL MORNING...BUT AS THE SURFACE CAPES
REACH 2K OR MORE...CONVECTION WILL REFIRE ALONG THE SEA BREEZE
RESULTANT. CONVECTION MAY OVERPOWER THE RESULTANT AND AFFECT THE
COASTAL TERMINALS THROUGH MUCH OF THE AFTERNOON...POSSIBLY EARLY
EVENING. LOOK FOR MVFR CEILINGS AND BRIEF IFR VISIBILITIES IN THE
HEAVY RAIN. SCATTERED CONVECTION WILL ALSO AFFECT INLAND
TERMINALS...BUT CONFIDENCE IS LOWER WITH RESPECT TO TIMING AND
INTENSITY. TONIGHT...CONVECTION WILL WANE...BUT MORE NOCTURNAL
SHOWERS COULD ERUPT OFFSHORE...POSSIBLY COMING NEAR THE MYRTLES AND
ILM THROUGH THE OVERNIGHT HOURS.
EXTENDED OUTLOOK...UNSETTLED WEATHER THROUGH THURSDAY WITH A GOOD
CHANCE FOR SHOWERS/ISOLATED THUNDERSTORMS/TEMPO MVFR. VFR FRIDAY
THROUGH SUNDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 10:30 AM WEDNESDAY...LATEST OBS SHOWS SOUTHERLY WINDS IN THE
10 KT RANGE...WITH SEAS OF AROUND 3 FT. THIS IS RIGHT AS FORECAST
FOR THIS TIME OF DAY. PREVIOUS DISCUSSION STILL APPLIES AND FOLLOWS
BELOW:
SEA HEIGHTS AND SYNOPTIC WINDS WILL NOT POSE A THREAT TODAY...BUT
ISOLATED TO SCATTERED THUNDERSTORMS MAY PRODUCE TREACHEROUS
CONDITIONS LOCALLY...LATER TODAY AND TONIGHT AS A WEAK COLD FRONT
APPROACHES THE COAST. MARINERS SHOULD CONSULT RADAR TRENDS BEFORE
HEADING OUT TO ASCERTAIN THE LOCAL RISKS. ELSE-WISE...SEAS
GENERALLY COMPOSED OF SE WAVES 3-4 FEET IN 7 SECONDS INTERVALS
WITH A LIGHT SSW CHOP. WINDS AND WIND-WAVES IN AND NEAR TSTMS WILL
BE LOCALLY MUCH HIGHER. WINDS TO SHIFT TO NW BUT OVERALL LIGHT
WIND-SPEEDS IN THE PRE-DAWN HOURS OF THU AS A WEAK COLD FRONT
MOVES OFFSHORE BY SUNRISE.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 AM WEDNESDAY...THURSDAY IS A TRANSITION DAY AS A COLD
FRONT CROSSES THE WATERS EARLY IN THE DAY. NW WINDS OF 5-10 KTS
EARLY THURSDAY WILL BECOME NE LATE IN THE DAY AND BEGIN TO INCREASE
ON A NE SURGE AS HIGH PRESSURE RIDGES DOWN THE COAST. WINDS INCREASE
TO 10-15 KTS THURSDAY NIGHT WHICH HELPS BUILD SEAS FROM 2-3 FT UP TO
3-4 FT...WITH THE NE WIND CHOP BECOMING INCREASINGLY MORE DOMINANT
IN THE SPECTRUM. NE WINDS INCREASE FURTHER FRIDAY...TO 15-20 KTS
THROUGH THE DAY. THIS BUILDS SEAS FURTHER...TO 4-5 FT...AND SCEC
HEADLINES MAY BE NEEDED LATE IN THE DAY.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 300 AM WEDNESDAY...CONTINUED STRONG NE WINDS THROUGH THE WKND
WILL LIKELY NECESSITATE A SMALL CRAFT ADVISORY THROUGH THE ENTIRE
EXTENDED. NE WINDS OF 15-20 KTS WILL PERSIST THROUGH THE WKND WITH
ONLY MINOR DIURNAL VARIATIONS. THIS BUILDS SEAS TO 4-6 FT BEGINNING
VERY EARLY SATURDAY AND PERSISTING THROUGH SUNDAY NIGHT...WITH A
6SEC NE WIND WAVE BEING THE DOMINANT FEATURE IN THE SEA SPECTRUM. AS
IS FREQUENTLY THE CASE WITH NE SURGES...THE HIGHEST SEAS WILL BE
BLOCKED BY THE FRYING PAN SHOALS...SO A SHADOW REGION OF 2-4 FT SEAS
IN THE INNER 10NM ALONG BRUNSWICK AND NORTHERN HORRY COUNTIES WILL
EXIST THROUGH THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JDW
NEAR TERM...MJC/REK
SHORT TERM...JDW
LONG TERM...JDW
AVIATION...MJC
MARINE...MJC/REK/JDW
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1119 AM EDT WED MAY 16 2012
.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE THROUGH THE AREA ON WEDNESDAY. HIGH
PRESSURE WILL THEN BUILD IN FOR THE REST OF THE WEEK...WITH
GRADUALLY WARMING TEMPERATURES INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
A WEAK COLD FRONT WILL DROP SOUTHWARD THROUGH THE REGION THIS
AFTERNOON. THE FRONT SEEMS TO BE JUST A TAD SLOWER THAN PREVIOUSLY
FORECAST. FORECAST CHALLENGES WITH THIS FRONT REVOLVE AROUND
CHANCES OF PCPN AND TEMPERATURES. FORCING IS WEAK WITH THE FRONT.
ALSO...INSTABILITY WILL BE LIMITED...MORE SO THAN WHAT THE NAM-WRF
AND GFS ARE INDICATING AS THEY HAVE BEEN POOLING MUCH HIGHER
DEWPOINTS AHEAD OF THE FRONT THAN WHAT HAS BEEN ACTUALLY
OCCURRING. THUS...HAVE SIDED WITH THE MORE LOWER DEWPOINT VALUES
WITH THE RAP MODEL WHICH YIELD MLCAPES OF ABOUT 1000 J/KG LATE IN
THE DAY ACRS THE SRN ZONES. AS A RESULT...HAVE PLACED A 20 POP
AHEAD OF THE FRONT ACRS THE NORTH FOR AN ISOLATED SHOWER THROUGH
LATE AFTN. THEREAFTER...HAVE PLACED A 20 POP IN THE SRN ZONES FOR
AN ISOLATED SHOWER/THUNDERSTORM LATE IN THE DAY INTO THE EARLY
EVENING HOURS. FRONTAL PASSAGE WILL BE DELINEATED WITH A WIND
SHIFT TO THE NORTH ALONG WITH SOME GUSTS AS HIGH AS 25 MPH.
TEMPERATURES WILL BE TRICKY GIVEN CLOUDS AND CAA ASSOCIATED WITH
AND JUST BEHIND THE FRONT. HIGHS TODAY SHOULD RANGE FROM NEAR 70
IN THE FAR NW TO THE LOWER 80S IN THE SOUTH.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
THE COLD FRONT AND ANY REMAINING THUNDERSTORMS WILL SHIFT SOUTH OF
OUR AREA THIS EVENING. IN THE WAKE OF THE FRONT...COLD ADVECTION
WILL LIKELY KEEP WINDS UP AROUND 10 MPH FOR MOST OF THE OVERNIGHT
PERIOD. WITH THE COOLER AND DRIER AIRMASS MOVING INTO
PLACE...OVERNIGHT LOWS WILL RUN ABOUT 10 DEGREES COOLER THAN THIS
MORNINGS VALUES. HAVE FORECAST LOW A DEGREE OR TWO ABOVE
GUIDANCE...MAINLY DUE TO WINDS NOT GOING COMPLETELY CALM
OVERNIGHT.
THURSDAY THROUGH FRIDAY...RIDGING WILL DOMINATE OUR WEATHER WITH
ONLY SCATTERED CLOUDS...NO PRECIPITATION...AND GRADUALLY
REBOUNDING TEMPERATURES. MAXIMUM TEMPERATURES WILL BE NEAR CLIMO
ON THURSDAY. THURSDAY NIGHT WILL BE COOL...WITH UPPER 40S TO LOW
50S WITH CLEAR SKIES...CALM WINDS...AND DEWPOINTS IN THE 30S TO
40S.
THE SURFACE RIDGE WILL SHIFT EAST ON FRIDAY...AND MID LEVEL
HEIGHTS AND CORRESPONDING THICKNESSES WILL INCREASE. THIS WILL
LEAD TO HIGH TEMPERATURES ON FRIDAY SEVERAL DEGREES WARMER THAN
THURSDAY...UNDER MOSTLY CLEAR SKIES.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
MODELS ARE IN GENERAL AGREEMENT FOR THE LONG TERM TIME FRAME. DRY
CONDITIONS WILL BE PRESENT TO START OUT THE LONG TERM WITH HIGH
PRESSURE IN PLACE. PREVIOUS MODEL RUNS WERE TRYING TO ALLOW FOR A
FEW THUNDERSTORMS TO DEVELOP DURING THE AFTERNOON SATURDAY AND
SUNDAY. MOST RECENT MODEL RUNS HAVE COME IN DRIER FOR THE WEEKEND
AND BELIEVE THAT WITH THE RIDGE IN PLACE THAT DRY CONDITIONS WILL
PREVAIL. TEMPERATURES WILL GRADUALLY INCREASE THROUGH THE WEEKEND
WITH WARM SOUTHERLY FLOW. TEMPERATURES ON MONDAY WILL BE SIMILAR TO
SUNDAY WITH SOME LOCATIONS A DEGREE OR TWO COOLER THAN SUNDAY DUE TO
AN INCREASE IN CLOUD COVER. MODELS CONTINUE TO SLOW DOWN THE SYSTEM
FOR MONDAY AND TUESDAY AND THEREFORE LIMITED PRECIPITATION CHANCES
ON MONDAY AND MOST OF MONDAY NIGHT TO A SLIGHT CHANCE. EXPECT
TEMPERATURES TO BE A LITTLE COOLER ON TUESDAY WITH INCREASED
PRECIPITATION AND CLOUD COVER ACROSS THE FA.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
A COLD FRONT IS PUSHING DOWN TOWARD THE AREA THIS MORNING...
CURRENTLY STRETCHING FROM NORTHWEST OHIO ACROSS NORTHERN INDIANA
INTO CENTRAL ILLINOIS. SOME DEBRIS CLOUDINESS AHEAD OF THE FRONT
WILL LIKELY WORK ACROSS THE TAF SITES THROUGH MID MORNING. AS THE
FRONT MOVES SOUTH ACROSS THE AREA...THE AIRMASS ALONG AND SOUTH OF
THE FRONT WILL BEGIN TO DESTABILIZE THROUGH THIS AFTERNOON. THIS
WILL LIKELY LEAD TO SOME CU DEVELOPMENT LATE THIS MORNING INTO
EARLY AFTERNOON. EVENTUALLY SOME SHOWERS AND A FEW THUNDERSTORMS
WILL LIKELY DEVELOP AHEAD OF THE FRONT THIS AFTERNOON.
HOWEVER...BY THIS TIME THE FRONT SHOULD BE SOUTH OF TH TAF SITES
SO WILL KEEP PCPN OUT OF THE FORECAST. SKIES SHOULD THEN CLEAR ON
THE BACK SIDE OF THE FRONT LATER THIGH AFTERNOON INTO THIS
EVENING.
OUTLOOK...NO SIGNIFICANT WEATHER EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...LATTO
NEAR TERM...HICKMAN
SHORT TERM...LATTO
LONG TERM...NOVAK
AVIATION...JGL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
449 PM MDT WED MAY 16 2012
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 150 PM MDT WED MAY 16 2012
EARLY AFTERNOON WV IMAGERY AND RUC H5 ANALYSIS SHOW SHORTWAVE RIDGE
OVER WESTERN KS BEGINNING TO BREAK DOWN AS SHORTWAVE TROUGH OVER
GREAT BASIN CONTINUES TO MOVE EAST INTO THE CENTRAL ROCKIES. TIGHT
GRADIENT CURRENTLY IN PLACE ACROSS CWA NO EASTERN EXTENT OF LEE
TROUGH HAS LED TO BREEZY CONDITIONS ACROSS THE AREA...WITH WINDS
GUSTING AROUND 30KT AT SEVERAL LOCATIONS. A WARM FRONT JUST
SOUTHWEST OF GOODLAND LIFTING TO THE NORTHEAST. WEST OF THIS FRONT
RH VALUES HAVE DROPPED TO 15% OR LOWER. WITH SEVERAL LOCATIONS
ALREADY WITHIN RED FLAG CRITERIA...PLAN ON KEEPING RFW IN PLACE
THROUGH EXPIRATION (02Z).
SHORTWAVE TROUGH WILL CONTINUE TO MOVE EAST WITH LARGE SCALE ASCENT
SPREADING INTO EASTERN COLORADO. RADAR RETURNS ALREADY SHOWING
SHOWERS/THUNDERSTORMS ALONG FRONT RANGE...WITH ACTIVITY GENERALLY
MOVING FROM THE SOUTH TO NORTH. LATEST RUC/HRRR SHOW THIS ACTIVITY
REMAINING JUST EAST OF THE CWA. WITH LARGE SCALE ASCENT STILL
EXPECTED TO OVERSPREAD THE CWA...AND THE CLOSE PROXIMITY OF
ACTIVITY...I DECIDED TO LEAVE ISOLATED THUNDERSTORMS IN FORECAST
THIS EVENING.
SHORTWAVE TROUGH AXIS CURRENTLY PROGGED TO MOVE EAST ACROSS WESTERN
KS. GUIDANCE IN GENERAL AGREEMENT ON TIMING...HOWEVER STRENGTH AND
POSITION OF SHORTWAVE ARE STILL ISSUES...WITH KEEPING OUR CWA
DRY...AND OTHER GUIDANCE FAVORING THE SOUTH AND EAST LATE THURSDAY
AFTERNOON. WITH INSTABILITY/LARGE SCALE ASCENT ACROSS THE CWA
THURSDAY...SLIGHT CHANCE POPS FROM PREVIOUS FORECAST SEEMED
REASONABLE. TIGHT SURFACE GRADIENT WILL REMAIN IN PLACE OVER EASTERN
PARTS OF CWA...WITH NAM/GFS BL WINDS APPROACHING ADVISORY CRITERIA
FOR A PERIOD OF TIME THURSDAY AFTERNOON. CONFIDENCE IS NOT THERE
THAT ADVISORY CRITERIA WINDS WILL LAST 3HR...SO NO HAZARD PLANNED.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 248 PM MDT WED MAY 16 2012
THURSDAY EVENING THE SHORT WAVE TROUGH WILL CONTINUE TO MOVE EAST
ACROSS THE AREA. LATEST GUIDANCE DISAGREES WITH THE LOCATION OF THE
SHORT WAVE TROUGH DURING THE EVENING...WITH THE GFS SHIFTING THE
TROUGH FURTHER NORTH WHILE THE NAM HAS KEPT THE TROUGH OVER THE
SOUTHERN PART OF THE AREA. WITH MODELS NOT BEING CONSISTANT WITH
THE PLACEMENT OF THE SHORT WAVE TROUGH...WILL EXPAND THE SLIGHT
CHANCES TO INCLUDE THE ENTIRE AREA EAST OF THE COLORADO LINE. WITH
A DEEP WELL MIXED LAYER IN PLACE OVER THE AREA...STRONG DOWN BURST
WINDS WILL BE POSSIBLE WITH ANY THUNDERSTORM THAT DEVELOPS DURING
THE EARLY EVENING. THE SHORT WAVE TROUGH AND MID LEVEL CAPE WILL
EXIT THE AREA AROUND MIDNIGHT BRINGING ANY CHANCE FOR PRECIPITATION
TO AN END.
FRIDAY A DRY LINE SETS UP OVER THE CENTRAL PART OF THE AREA. DURING THE
MID TO LATE AFTERNOON A SHORT WAVE TROUGH MOVES OVER THE DRY LINE.
POINT SOUNDINGS FOR THE AREA SHOW THE ENVIRONMENT NEARING SATURATION
AROUND THE 500MB LEVEL ON UP...SO AM THINKING THE STORM DEVELOPMENT
WILL BE TIED TO THE LOCATION OF THE 500MB LIFT. HOWEVER CANNOT RULE
OUT ENOUGH CONVERGENCE OCCURRING OVER THE DRY LINE FOR A STORM OR TWO
TO INITIATION...SO HAVE PLACED SLIGHT CHANCES ALONG THE DRY LINE WITH
FOCUS ON THE BETTER AREA OF 500MB LIFT DURING THE LATE
AFTERNOON. WITH THE DEEP WELL MIXED ENVIRONMENT OVER THE
AREA...STRONG DOWN BURST WINDS ARE POSSIBLE WITH ANY STORM THAT
DEVELOPS DURING THE EARLY EVENING. THE SHORT WAVE TROUGH EXITS THE
AREA AROUND MIDNIGHT...BRINGING PRECIPITATION CHANCES TO AN END.
SOUTH WINDS WILL INCREASE DURING THE LATE MORNING AND AFTERNOON AS
STRONGER WINDS ABOVE THE SURFACE MIX DOWN TO THE GROUND. THE
SURFACE PRESSURE GRADIENT WILL ALSO TIGHTEN THROUGH THE AFTERNOON
AHEAD OF THE COLD FRONT THAT WILL MOVE THROUGH DURING THE OVERNIGHT
HOURS. WINDS WILL PEAK DURING THE LATE AFTERNOON...WITH GUSTS UP TO
40 MPH POSSIBLE. THE WINDS WILL EASE SOME DURING THEN EVENING AS
MIXING CEASES...BUT WILL STILL BE GUSTY DUE TO THE TIGHT PRESSURE
GRADIENT IN PLACE AHEAD OF THE COLD FRONT.
DURING THE OVERNIGHT HOURS A COLD FRONT WILL MOVE INTO THE AREA FROM
THE NORTHWEST. LATEST CROSS SECTIONS SHOW THE LIFT TO BE SITUATED
AHEAD OF THE FRONT IN THE DRIER AIR. WILL BE KEEPING THE FRONTAL
PASSAGE FOR THE OVERNIGHT PERIOD DRY AS A RESULT.
THE SATURDAY THROUGH FRIDAY PERIOD WILL START OFF WITH PRECIPITATION
CHANCES ACROSS MOST OF THE AREA SATURDAY...FOLLOWING A SHORT WAVE
TROUGH AND COLD FRONT THAT WILL MOVE THROUGH THE AREA DURING THE
DAY. BULK OF THE MOISTURE WILL BE OVER THE NORTHERN HALF OF THE
AREA...CAUSING PRECIPITATION CHANCES TO QUICKLY DECREASE OVER THE
SOUTHERN PART OF THE AREA THAT WILL BE IN THE DRIER AIR. BEHIND THE
FRONT WINDS WILL BE GUSTY...BUT SHOULD DECLINE THROUGH THE DAY AS
THE FRONT MOVES FURTHER SOUTH.
SATURDAY EVENING PRECIPITATION CHANCES CONTINUE AS THE SHORT WAVE
TROUGH MOVES ACROSS THE EASTERN PART OF THE AREA. MODELS HAVE A
SECOND SHORT WAVE TROUGH FOLLOWING THE FIRST ONE OVER THE WESTERN
PART OF THE AREA. AM NOT TOO CONFIDENT THERE WILL BE MUCH MOISTURE
FOR THE SECOND SHORT WAVE TO WORK WITH...BUT KEPT IN SLIGHT CHANCES
FOR THE REST OF THE AREA TO STAY CONSISTANT WITH NEIGHBORS.
PRECIPITATION CHANCES RETURN WEDNESDAY TO THE EASTERN PART OF THE
AREA AS ANOTHER SHORT WAVE TROUGH MOVES ACROSS THE AREA.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 449 PM MDT WED MAY 16 2012
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD AT BOTH
TERMINALS. A LEE TROUGH WILL CONTINUE TO BE LOCATED OVER EASTERN
COLORADO TONIGHT AND SLOWLY MOVE INTO WESTERN KANSAS THURSDAY.
WINDS WILL CONTINUE TO BE GUSTY THROUGH THE OVERNIGHT HOURS WITH
GUSTS OF 18-20 KNOTS POSSIBLE. LOW LEVEL JET WILL STRENGTHEN
OVERNIGHT WITH LLWS POSSIBLE AT BOTH TERMINALS. HOWEVER...WITH
SURFACE WINDS GUSTY OVERNIGHT...FEEL THAT WILL NOT MEET LLWS
CRITERIA SO WILL KEEP OUT OF SIGHT ATTM AND CONTINUE TO WATCH
THROUGH THE EVENING HOURS. WINDS WILL BE GUSTY ON THURSDAY AND
MID LEVEL CLOUDS WILL INCREASE AS A DISTURBANCE MOVES INTO THE
REGION. ISOLATED THUNDERSTORMS ARE POSSIBLE THURSDAY BUT
TIMING/COVERAGE IS UNCERTAIN SO WILL KEEP OUT OF TAFS.
&&
.FIRE WEATHER...
ISSUED AT 248 PM MDT WED MAY 16 2012
FRIDAY AFTERNOON SOUTH WINDS WILL STRENGTHEN...WITH GUSTS UP TO 40
MPH ACROSS THE AREA. RELATIVE HUMIDITIES WILL FALL INTO THE 10 TO
20 PERCENT RANGE DURING THE AFTERNOON FOR LOCATIONS WEST OF A
MCCOOK TO GOVE LINE...LEADING TO HAZARDOUS FIRE WEATHER
CONDITIONS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...RED FLAG WARNING UNTIL 8 PM MDT /9 PM CDT/ THIS EVENING FOR
KSZ001-013-027.
CO...RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ252>254.
NE...RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR NEZ079.
&&
$$
SHORT TERM...DR
LONG TERM...JTL
AVIATION...BAS
FIRE WEATHER...JTL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
251 PM MDT WED MAY 16 2012
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 150 PM MDT WED MAY 16 2012
EARLY AFTERNOON WV IMAGERY AND RUC H5 ANALYSIS SHOW SHORTWAVE RIDGE
OVER WESTERN KS BEGINNING TO BREAK DOWN AS SHORTWAVE TROUGH OVER
GREAT BASIN CONTINUES TO MOVE EAST INTO THE CENTRAL ROCKIES. TIGHT
GRADIENT CURRENTLY IN PLACE ACROSS CWA NO EASTERN EXTENT OF LEE
TROUGH HAS LED TO BREEZY CONDITIONS ACROSS THE AREA...WITH WINDS
GUSTING AROUND 30KT AT SEVERAL LOCATIONS. A WARM FRONT JUST
SOUTHWEST OF GOODLAND LIFTING TO THE NORTHEAST. WEST OF THIS FRONT
RH VALUES HAVE DROPPED TO 15% OR LOWER. WITH SEVERAL LOCATIONS
ALREADY WITHIN RED FLAG CRITERIA...PLAN ON KEEPING RFW IN PLACE
THROUGH EXPIRATION (02Z).
SHORTWAVE TROUGH WILL CONTINUE TO MOVE EAST WITH LARGE SCALE ASCENT
SPREADING INTO EASTERN COLORADO. RADAR RETURNS ALREADY SHOWING
SHOWERS/THUNDERSTORMS ALONG FRONT RANGE...WITH ACTIVITY GENERALLY
MOVING FROM THE SOUTH TO NORTH. LATEST RUC/HRRR SHOW THIS ACTIVITY
REMAINING JUST EAST OF THE CWA. WITH LARGE SCALE ASCENT STILL
EXPECTED TO OVERSPREAD THE CWA...AND THE CLOSE PROXIMITY OF
ACTIVITY...I DECIDED TO LEAVE ISOLATED THUNDERSTORMS IN FORECAST
THIS EVENING.
SHORTWAVE TROUGH AXIS CURRENTLY PROGGED TO MOVE EAST ACROSS WESTERN
KS. GUIDANCE IN GENERAL AGREEMENT ON TIMING...HOWEVER STRENGTH AND
POSITION OF SHORTWAVE ARE STILL ISSUES...WITH KEEPING OUR CWA
DRY...AND OTHER GUIDANCE FAVORING THE SOUTH AND EAST LATE THURSDAY
AFTERNOON. WITH INSTABILITY/LARGE SCALE ASCENT ACROSS THE CWA
THURSDAY...SLIGHT CHANCE POPS FROM PREVIOUS FORECAST SEEMED
REASONABLE. TIGHT SURFACE GRADIENT WILL REMAIN IN PLACE OVER EASTERN
PARTS OF CWA...WITH NAM/GFS BL WINDS APPROACHING ADVISORY CRITERIA
FOR A PERIOD OF TIME THURSDAY AFTERNOON. CONFIDENCE IS NOT THERE
THAT ADVISORY CRITERIA WINDS WILL LAST 3HR...SO NO HAZARD PLANNED.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 248 PM MDT WED MAY 16 2012
THURSDAY EVENING THE SHORT WAVE TROUGH WILL CONTINUE TO MOVE EAST
ACROSS THE AREA. LATEST GUIDANCE DISAGREES WITH THE LOCATION OF THE
SHORT WAVE TROUGH DURING THE EVENING...WITH THE GFS SHIFTING THE
TROUGH FURTHER NORTH WHILE THE NAM HAS KEPT THE TROUGH OVER THE
SOUTHERN PART OF THE AREA. WITH MODELS NOT BEING CONSISTANT WITH
THE PLACEMENT OF THE SHORT WAVE TROUGH...WILL EXPAND THE SLIGHT
CHANCES TO INCLUDE THE ENTIRE AREA EAST OF THE COLORADO LINE. WITH
A DEEP WELL MIXED LAYER IN PLACE OVER THE AREA...STRONG DOWN BURST
WINDS WILL BE POSSIBLE WITH ANY THUNDERSTORM THAT DEVELOPS DURING
THE EARLY EVENING. THE SHORT WAVE TROUGH AND MID LEVEL CAPE WILL
EXIT THE AREA AROUND MIDNIGHT BRINGING ANY CHANCE FOR PRECIPITATION
TO AN END.
FRIDAY A DRY LINE SETS UP OVER THE CENTRAL PART OF THE AREA. DURING THE
MID TO LATE AFTERNOON A SHORT WAVE TROUGH MOVES OVER THE DRY LINE.
POINT SOUNDINGS FOR THE AREA SHOW THE ENVIRONMENT NEARING SATURATION
AROUND THE 500MB LEVEL ON UP...SO AM THINKING THE STORM DEVELOPMENT
WILL BE TIED TO THE LOCATION OF THE 500MB LIFT. HOWEVER CANNOT RULE
OUT ENOUGH CONVERGENCE OCCURRING OVER THE DRY LINE FOR A STORM OR TWO
TO INITIATION...SO HAVE PLACED SLIGHT CHANCES ALONG THE DRY LINE WITH
FOCUS ON THE BETTER AREA OF 500MB LIFT DURING THE LATE
AFTERNOON. WITH THE DEEP WELL MIXED ENVIRONMENT OVER THE
AREA...STRONG DOWN BURST WINDS ARE POSSIBLE WITH ANY STORM THAT
DEVELOPS DURING THE EARLY EVENING. THE SHORT WAVE TROUGH EXITS THE
AREA AROUND MIDNIGHT...BRINGING PRECIPITATION CHANCES TO AN END.
SOUTH WINDS WILL INCREASE DURING THE LATE MORNING AND AFTERNOON AS
STRONGER WINDS ABOVE THE SURFACE MIX DOWN TO THE GROUND. THE
SURFACE PRESSURE GRADIENT WILL ALSO TIGHTEN THROUGH THE AFTERNOON
AHEAD OF THE COLD FRONT THAT WILL MOVE THROUGH DURING THE OVERNIGHT
HOURS. WINDS WILL PEAK DURING THE LATE AFTERNOON...WITH GUSTS UP TO
40 MPH POSSIBLE. THE WINDS WILL EASE SOME DURING THEN EVENING AS
MIXING CEASES...BUT WILL STILL BE GUSTY DUE TO THE TIGHT PRESSURE
GRADIENT IN PLACE AHEAD OF THE COLD FRONT.
DURING THE OVERNIGHT HOURS A COLD FRONT WILL MOVE INTO THE AREA FROM
THE NORTHWEST. LATEST CROSS SECTIONS SHOW THE LIFT TO BE SITUATED
AHEAD OF THE FRONT IN THE DRIER AIR. WILL BE KEEPING THE FRONTAL
PASSAGE FOR THE OVERNIGHT PERIOD DRY AS A RESULT.
THE SATURDAY THROUGH FRIDAY PERIOD WILL START OFF WITH PRECIPITATION
CHANCES ACROSS MOST OF THE AREA SATURDAY...FOLLOWING A SHORT WAVE
TROUGH AND COLD FRONT THAT WILL MOVE THROUGH THE AREA DURING THE
DAY. BULK OF THE MOISTURE WILL BE OVER THE NORTHERN HALF OF THE
AREA...CAUSING PRECIPITATION CHANCES TO QUICKLY DECREASE OVER THE
SOUTHERN PART OF THE AREA THAT WILL BE IN THE DRIER AIR. BEHIND THE
FRONT WINDS WILL BE GUSTY...BUT SHOULD DECLINE THROUGH THE DAY AS
THE FRONT MOVES FURTHER SOUTH.
SATURDAY EVENING PRECIPITATION CHANCES CONTINUE AS THE SHORT WAVE
TROUGH MOVES ACROSS THE EASTERN PART OF THE AREA. MODELS HAVE A
SECOND SHORT WAVE TROUGH FOLLOWING THE FIRST ONE OVER THE WESTERN
PART OF THE AREA. AM NOT TOO CONFIDENT THERE WILL BE MUCH MOISTURE
FOR THE SECOND SHORT WAVE TO WORK WITH...BUT KEPT IN SLIGHT CHANCES
FOR THE REST OF THE AREA TO STAY CONSISTANT WITH NEIGHBORS.
PRECIPITATION CHANCES RETURN WEDNESDAY TO THE EASTERN PART OF THE
AREA AS ANOTHER SHORT WAVE TROUGH MOVES ACROSS THE AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1217 PM MDT WED MAY 16 2012
VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD AT BOTH KGLD AND
KMCK. GUSTY WINDS EXPECTED THROUGH MOST OF THE TAF PERIOD AT BOTH
SITES WITH STRONGEST WINDS THIS AFTERNOON 25-30KT. WINDS SHOULD
DECREASE SLIGHTLY AFTER SUNSET...THOUGH THEY WILL REMAIN GUSTY AT
BOTH TERMINALS THROUGH THURSDAY MORNING AS UPPER LEVEL DISTURBANCE
MOVES EAST. THERE IS A SMALL CHANCE FOR A THUNDERSTORM AT KGLD THIS
AFTERNOON/EVENING AND AT BOTH KGLD AND KMCK THURSDAY AFTERNOON.
COVERAGE WILL BE VERY LIMITED...SO LEFT MENTION OUT OF TAFS.
&&
.FIRE WEATHER...
ISSUED AT 248 PM MDT WED MAY 16 2012
FRIDAY AFTERNOON SOUTH WINDS WILL STRENGTHEN...WITH GUSTS UP TO 40
MPH ACROSS THE AREA. RELATIVE HUMIDITIES WILL FALL INTO THE 10 TO
20 PERCENT RANGE DURING THE AFTERNOON FOR LOCATIONS WEST OF A
MCCOOK TO GOVE LINE...LEADING TO HAZARDOUS FIRE WEATHER
CONDITIONS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...RED FLAG WARNING UNTIL 8 PM MDT /9 PM CDT/ THIS EVENING FOR
KSZ001-013-027.
CO...RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ252>254.
NE...RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR NEZ079.
&&
$$
SHORT TERM...DR
LONG TERM...JTL
AVIATION...DR
FIRE WEATHER...JTL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
151 PM MDT WED MAY 16 2012
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 150 PM MDT WED MAY 16 2012
EARLY AFTERNOON WV IMAGERY AND RUC H5 ANALYSIS SHOW SHORTWAVE RIDGE
OVER WESTERN KS BEGINNING TO BREAK DOWN AS SHORTWAVE TROUGH OVER
GREAT BASIN CONTINUES TO MOVE EAST INTO THE CENTRAL ROCKIES. TIGHT
GRADIENT CURRENTLY IN PLACE ACROSS CWA NO EASTERN EXTENT OF LEE
TROUGH HAS LED TO BREEZY CONDITIONS ACROSS THE AREA...WITH WINDS
GUSTING AROUND 30KT AT SEVERAL LOCATIONS. A WARM FRONT JUST
SOUTHWEST OF GOODLAND LIFTING TO THE NORTHEAST. WEST OF THIS FRONT
RH VALUES HAVE DROPPED TO 15% OR LOWER. WITH SEVERAL LOCATIONS
ALREADY WITHIN RED FLAG CRITERIA...PLAN ON KEEPING RFW IN PLACE
THROUGH EXPIRATION (02Z).
SHORTWAVE TROUGH WILL CONTINUE TO MOVE EAST WITH LARGE SCALE ASCENT
SPREADING INTO EASTERN COLORADO. RADAR RETURNS ALREADY SHOWING
SHOWERS/THUNDERSTORMS ALONG FRONT RANGE...WITH ACTIVITY GENERALLY
MOVING FROM THE SOUTH TO NORTH. LATEST RUC/HRRR SHOW THIS ACTIVITY
REMAINING JUST EAST OF THE CWA. WITH LARGE SCALE ASCENT STILL
EXPECTED TO OVERSPREAD THE CWA...AND THE CLOSE PROXIMITY OF
ACTIVITY...I DECIDED TO LEAVE ISOLATED THUNDERSTORMS IN FORECAST
THIS EVENING.
SHORTWAVE TROUGH AXIS CURRENTLY PROGGED TO MOVE EAST ACROSS WESTERN
KS. GUIDANCE IN GENERAL AGREEMENT ON TIMING...HOWEVER STRENGTH AND
POSITION OF SHORTWAVE ARE STILL ISSUES...WITH KEEPING OUR CWA
DRY...AND OTHER GUIDANCE FAVORING THE SOUTH AND EAST LATE THURSDAY
AFTERNOON. WITH INSTABILITY/LARGE SCALE ASCENT ACROSS THE CWA
THURSDAY...SLIGHT CHANCE POPS FROM PREVIOUS FORECAST SEEMED
REASONABLE. TIGHT SURFACE GRADIENT WILL REMAIN IN PLACE OVER EASTERN
PARTS OF CWA...WITH NAM/GFS BL WINDS APPROACHING ADVISORY CRITERIA
FOR A PERIOD OF TIME THURSDAY AFTERNOON. CONFIDENCE IS NOT THERE
THAT ADVISORY CRITERIA WINDS WILL LAST 3HR...SO NO HAZARD PLANNED.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 244 AM MDT WED MAY 16 2012
THURSDAY NIGHT-FRIDAY NIGHT...WEAK SHORT WAVE RIDGING WILL BUILD
OVER THE AREA DURING THE EVENING HOURS...BRINGING AN END TO ANY
PRECIP CHANCES DURING THE OVERNIGHT HOURS. NEXT SHORT WAVE TROUGH
WILL MOVE OVER THE FOUR CORNERS AREA AND INTO COLORADO BY FRIDAY
NIGHT. WHILE LARGE SCALE FORCING FOR ASCENT WITH UPPER TROUGH NOT
EXPECTED TO INFLUENCE THE AREA DIRECTLY UNTIL AROUND 12Z WHEN COLD
FRONT ENTERS CWA...HAVE SOME CONCERNS ABOUT POTENTIAL FOR
THUNDERSTORMS ALONG SFC TROUGH/DRYLINE LATE FRIDAY AFTERNOON AND
EVENING. STRONGEST LOW LEVEL CONVERGENCE EXPECTED TO THE SOUTH OF
SFC LOW CENTERED OVER NORTHEASTERN COLORADO/NEB PANHANDLE. MOISTURE
ADVECTION LOOKS A BIT STRONGER THAN PREVIOUS SYSTEM WITH TDS IN THE
MID 40S TO LOW 50S EXPECTED EAST OF DRY LINE. WHILE THERE IS A SMALL
POTENTIAL FOR STORMS...THINK PROBABILITIES SHOULD REMAIN FAIRLY LOW
FOR THE TIME BEING AS HIGHEST TDS/INSTABILITY WILL BE WELL TO THE
EAST OF BEST SFC CONVERGENCE AND WITH LARGE SCALE FORCING NOT
BECOMING STRONG UNTIL AROUND 12Z THINK SFC FEATURES WILL BE PRIMARY
MEANS FOR ANY CONVECTIVE INITIATION. WINDS INCREASE SHARPLY DURING
THE DAY FRIDAY...ESPECIALLY TO THE EAST OF SFC TROUGH INCREASING
SHARPLY AROUND 00Z. STILL A FAIRLY LARGE DISCREPANCY ON HOW STRONG
WINDS ALOFT WILL BE...BUT THERE LOOKS TO BE AT LEAST SOME POTENTIAL
FOR ADVISORY TYPE WINDS LATE FRIDAY AFTERNOON AND EARLY EVENING.
WINDS SHOULD REMAIN STRONG/GUSTY DURING THE OVERNIGHT HOURS AHEAD OF
COLD FRONT KEEPING LOWS MUCH WARMER THAN THE PAST FEW DAYS WITH MANY
LOCATIONS SEEING LOWS STAY IN THE 60S.
A STRONG COLD FRONT WILL MOVE THROUGH THE REGION SATURDAY MORNING
AHEAD OF A SHORTWAVE TROUGH THAT WILL MOVE THROUGH THE CENTRAL
ROCKIES AND INTO KANSAS BEFORE SWINGING UP INTO NEBRASKA BY SATURDAY
EVENING. PRECIPITATION CHANCES WILL INCREASE AS THE FRONT MOVES
THROUGH THE REGION...WITH BEST CHANCES ACROSS THE NORTHERN HALF OF
THE CWA. DRY SLOT APPEARS TO DEVELOP AND WILL KEEP PRECIPITATION
CHANCES LOW ACROSS PARTS OF SOUTHEAST COLORADO AND SOUTHWEST KANSAS.
COOLER AIR WILL MOVE IN BEHIND THE FRONT WITH A GRADUAL WARMING
THROUGH NEXT WEEK. ANOTHER SHORTWAVE TROUGH WILL MOVE THROUGH THE
REGION ON SUNDAY...BUT WITH HIGHER SURFACE DEWPOINTS EXPECTED TO BE
MUCH FURTHER EASTWARD ACROSS EASTERN KANSAS...AM NOT EXPECTING
THUNDERSTORMS TO DEVELOP SUNDAY AFTERNOON. BY EARLY NEXT
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1217 PM MDT WED MAY 16 2012
VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD AT BOTH KGLD AND
KMCK. GUSTY WINDS EXPECTED THROUGH MOST OF THE TAF PERIOD AT BOTH
SITES WITH STRONGEST WINDS THIS AFTERNOON 25-30KT. WINDS SHOULD
DECREASE SLIGHTLY AFTER SUNSET...THOUGH THEY WILL REMAIN GUSTY AT
BOTH TERMINALS THROUGH THURSDAY MORNING AS UPPER LEVEL DISTURBANCE
MOVES EAST. THERE IS A SMALL CHANCE FOR A THUNDERSTORM AT KGLD THIS
AFTERNOON/EVENING AND AT BOTH KGLD AND KMCK THURSDAY AFTERNOON.
COVERAGE WILL BE VERY LIMITED...SO LEFT MENTION OUT OF TAFS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...RED FLAG WARNING UNTIL 8 PM MDT /9 PM CDT/ THIS EVENING FOR
KSZ001-013-027.
CO...RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ252>254.
NE...RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR NEZ079.
&&
$$
SHORT TERM...DR
LONG TERM...JRM/PM
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1217 PM MDT WED MAY 16 2012
.UPDATE...
ISSUED AT 911 AM MDT WED MAY 16 2012
FORECAST GENERALLY ON TRACK...WITH ONLY MINOR ADJUSTMENTS TO CATCH
LATEST TRENDS. TD FORECAST ACROSS EASTERN CWA MAY BE TOO HIGH
CONSIDERING LIMITED MOISTURE ADVECTION AND TD VALUES STARTING IN
THE MID TO HIGH 30S. LATEST RUC SEEMED TO HAVE A BETTER HANDLE ON
CURRENT TRENDS SO USED THAT AS A STARTING POINT. OVERALL THIS
RESULTS IN LOWER RH VALUES FURTHER EAST THAN PREVIOUSLY
ADVERTISED...WITH RFW CONDITIONS POSSIBLE FURTHER EAST. QUESTION
REMAINS FUELS ACROSS THE AREA...WITH CURRENT INDICATION THAT FUELS
REMAIN GREEN THE FURTHER EAST IN THE CWA. DISCUSSIONS WITH LOCAL
AUTHORITIES FROM DUNDY COUNTY AND NEAR THE CHEYENNE KANSAS BORDER
INDICATE FAVORABLE FUELS. WITH SHERMAN KS AND CHASE NE ALREADY
UNDER A RED FLAG WARNING I DECIDED TO EXTEND CURRENT RED FLAG
WARNING TO INCLUDE DUNDY AND CHEYENNE BASED ON THESE FUEL
OBSERVATIONS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 244 AM MDT WED MAY 16 2012
0330Z WATER VAPOR INDICATED SHORT WAVE RIDGE IN PLACE ACROSS THE THE
HIGH PLAINS...WITH CLOSED CIRCULATION ASSOCIATED WITH STRONG SHORT
WAVE TROUGH MOVING INTO SOUTHWESTERN UTAH. THIS TROUGH ALREADY
TAKING A MORE SOUTHERLY TRACK THAN PREVIOUSLY EXPECTED AND OVERALL
OBSERVED 12 HOUR HEIGHT FALLS PRETTY WEAK AHEAD OF THIS SYSTEM. 00Z
RAOBS INDICATE A WARM...WELL MIXED AND STABLE AIRMASS WAS IN PLACE
ACROSS THE AREA...WITH VERY DRY AIR/LOW PW`S AT DDC/DNR AND LBF. AT
THE SFC...1021MB SFC HIGH WAS CENTERED OVER NORTHEASTERN NEBRASKA
WITH COLD FRONT FROM APPROX KLAA TO KSLN TO KMCI.
MAIN FORECAST CONCERNS WILL BE FIRE WEATHER AND TEMPS
TODAY...FOLLOWED BY PRECIP CHANCES TONIGHT THROUGH THE WEEKEND.
SHORT TERM...SHORT WAVE TROUGH CURRENTLY MOVING INTO WESTERN UTAH
WILL BE PRIMARY INFLUENCE OF THE WEATHER ACROSS THE CWA AS IT
APPROACHES DURING THE DAY. DRY CONDITIONS ARE EXPECTED THROUGH MUCH
OF THE DAY...BUT SUBSIDENCE WILL DECREASE THROUGH THE MORNING HOURS
AS WEAK LARGE SCALE FORCING ASCENT INCREASES DURING THE AFTERNOON.
ALTHOUGH LIFT DOES INCREASE...LITTLE WITH ATMOSPHERE PROCEEDING
INCOMING TROUGH HAVING VERY LARGE TD DEPRESSIONS...THINK IT WILL BE
DIFFICULT TO HAVE MUCH CHANCE SATURATING/INITIATING ANYTHING UNTIL
VERY LATE IN THE DAY. WHILE BEST LARGE SCALE FORCING APPEARS TO
FAVOR EASTERN COLORADO...DO HAVE A FEW CONCERNS ABOUT CONVECTIVE
INITIATION ALONG RETREATING FRONTAL ZONE IN EASTERN CWA WHERE MORE
INSTABILITY/BETTER MOISTURE PROFILES ARE PRESENT. MAIN ISSUE HERE
WILL BE WHETHER CINH CAN BE OVERCOME AS VALUES ARE EXPECTED TO
REMAIN IN THE 50-150 J/KG RANGE. INITIAL PLAN WAS TO LEAVE OUT...BUT
WANT TO SEE SOME OF THE HIGHER RES DATA BEFORE MAKING A FINAL CALL
HERE. WINDS WILL INCREASE TO AROUND 20KTS IN AREAS SOUTH OF FRONTAL
ZONE. WITH DEEP MIXING EXPECTED TO DROP TDS SHARPLY TO SOUTH OF
FRONT AND CURRENT RFW LOOKS TO BE IN GOOD SHAPE. COULD MAKE AN
ARGUMENT FOR EXTENDING IT TO THE NORTH...BUT WITH RECENT RELATIVE
GREENNESS DATA SHOWING THINGS GREENING UP QUITE A BIT IN CHEYENNE
KS...THINK A WARNING NOT NEEDED AS FUELS MAY NOT BE CRITICAL.
OVERNIGHT LARGE SCALE FORCING FOR ASCENT WILL CONTINUE...ALTHOUGH
MORE SOUTHERLY TRACK OF SYSTEM RESULTS IN MUCH WEAKER AND A MORE
FURTHER WEST/SOUTH AREA OF MAXIMUM ASCENT. WITH THIS IN
MIND...CONFIDENCE MUCH LOWER THAN 24 HOURS AGO WITH RESPECT TO
PRECIP COVERAGE AND OVERALL CHANCES. HAVE DOUBTS THAT ANY STORMS
WILL MAKE IT MUCH FARTHER EAST THAN EASTERN COLORADO GIVEN THE VERY
LIMITED INSTABILITY AND MOISTURE PROFILES AND DO NOT THINK GOING
HIGHER THAN SLIGHT CHANCES AT THIS POINT. SHORT WAVE TROUGH WILL
CONTINUE TO IMPACT THE AREA THROUGH THE DAY THURSDAY...ALTHOUGH Q
VECTOR FIELDS SUGGEST LARGE SCALE FORCING FOR ASCENT WILL BE
MAXIMIZED TO THE SOUTH OF THE AREA. WHILE LARGE SCALE FORCING NOT
ALL THAT GREAT...INSTABILITY VALUES HIGHER AND WITH TEMPS ALOFT
COOLER CINH VALUES WEAKER. MOISTURE RETURN CONCERNS STILL EXIST FOR
PERIOD AS THERE DOES NOT APPEAR TO BE ANY MEANINGFUL MOISTURE
RETURN...SO THINK LIMITING POPS TO THE 20 PERCENT RANGE IN ORDER.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 244 AM MDT WED MAY 16 2012
THURSDAY NIGHT-FRIDAY NIGHT...WEAK SHORT WAVE RIDGING WILL BUILD
OVER THE AREA DURING THE EVENING HOURS...BRINGING AN END TO ANY
PRECIP CHANCES DURING THE OVERNIGHT HOURS. NEXT SHORT WAVE TROUGH
WILL MOVE OVER THE FOUR CORNERS AREA AND INTO COLORADO BY FRIDAY
NIGHT. WHILE LARGE SCALE FORCING FOR ASCENT WITH UPPER TROUGH NOT
EXPECTED TO INFLUENCE THE AREA DIRECTLY UNTIL AROUND 12Z WHEN COLD
FRONT ENTERS CWA...HAVE SOME CONCERNS ABOUT POTENTIAL FOR
THUNDERSTORMS ALONG SFC TROUGH/DRYLINE LATE FRIDAY AFTERNOON AND
EVENING. STRONGEST LOW LEVEL CONVERGENCE EXPECTED TO THE SOUTH OF
SFC LOW CENTERED OVER NORTHEASTERN COLORADO/NEB PANHANDLE. MOISTURE
ADVECTION LOOKS A BIT STRONGER THAN PREVIOUS SYSTEM WITH TDS IN THE
MID 40S TO LOW 50S EXPECTED EAST OF DRY LINE. WHILE THERE IS A SMALL
POTENTIAL FOR STORMS...THINK PROBABILITIES SHOULD REMAIN FAIRLY LOW
FOR THE TIME BEING AS HIGHEST TDS/INSTABILITY WILL BE WELL TO THE
EAST OF BEST SFC CONVERGENCE AND WITH LARGE SCALE FORCING NOT
BECOMING STRONG UNTIL AROUND 12Z THINK SFC FEATURES WILL BE PRIMARY
MEANS FOR ANY CONVECTIVE INITIATION. WINDS INCREASE SHARPLY DURING
THE DAY FRIDAY...ESPECIALLY TO THE EAST OF SFC TROUGH INCREASING
SHARPLY AROUND 00Z. STILL A FAIRLY LARGE DISCREPANCY ON HOW STRONG
WINDS ALOFT WILL BE...BUT THERE LOOKS TO BE AT LEAST SOME POTENTIAL
FOR ADVISORY TYPE WINDS LATE FRIDAY AFTERNOON AND EARLY EVENING.
WINDS SHOULD REMAIN STRONG/GUSTY DURING THE OVERNIGHT HOURS AHEAD OF
COLD FRONT KEEPING LOWS MUCH WARMER THAN THE PAST FEW DAYS WITH MANY
LOCATIONS SEEING LOWS STAY IN THE 60S.
A STRONG COLD FRONT WILL MOVE THROUGH THE REGION SATURDAY MORNING
AHEAD OF A SHORTWAVE TROUGH THAT WILL MOVE THROUGH THE CENTRAL
ROCKIES AND INTO KANSAS BEFORE SWINGING UP INTO NEBRASKA BY SATURDAY
EVENING. PRECIPITATION CHANCES WILL INCREASE AS THE FRONT MOVES
THROUGH THE REGION...WITH BEST CHANCES ACROSS THE NORTHERN HALF OF
THE CWA. DRY SLOT APPEARS TO DEVELOP AND WILL KEEP PRECIPITATION
CHANCES LOW ACROSS PARTS OF SOUTHEAST COLORADO AND SOUTHWEST KANSAS.
COOLER AIR WILL MOVE IN BEHIND THE FRONT WITH A GRADUAL WARMING
THROUGH NEXT WEEK. ANOTHER SHORTWAVE TROUGH WILL MOVE THROUGH THE
REGION ON SUNDAY...BUT WITH HIGHER SURFACE DEWPOINTS EXPECTED TO BE
MUCH FURTHER EASTWARD ACROSS EASTERN KANSAS...AM NOT EXPECTING
THUNDERSTORMS TO DEVELOP SUNDAY AFTERNOON. BY EARLY NEXT
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1217 PM MDT WED MAY 16 2012
VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD AT BOTH KGLD AND
KMCK. GUSTY WINDS EXPECTED THROUGH MOST OF THE TAF PERIOD AT BOTH
SITES WITH STRONGEST WINDS THIS AFTERNOON 25-30KT. WINDS SHOULD
DECREASE SLIGHTLY AFTER SUNSET...THOUGH THEY WILL REMAIN GUSTY AT
BOTH TERMINALS THROUGH THURSDAY MORNING AS UPPER LEVEL DISTURBANCE
MOVES EAST. THERE IS A SMALL CHANCE FOR A THUNDERSTORM AT KGLD THIS
AFTERNOON/EVENING AND AT BOTH KGLD AND KMCK THURSDAY AFTERNOON.
COVERAGE WILL BE VERY LIMITED...SO LEFT MENTION OUT OF TAFS.
&&
.FIRE WEATHER...
ISSUED AT 236 AM MDT WED MAY 16 2012
CRITICAL FIRE WEATHER CONDITIONS EXPECTED TODAY AS A DEVELOPING
SURFACE TROUGH BRINGS SOUTHERLY WINDS OF 15 TO 25 MPH TO THE AREA
AND AFTERNOON HUMIDITIES FALL TO LESS THAN 15 PERCENT ACROSS MUCH
OF THE AREA. BASED ON LATEST FUEL REPORTS AND AVAILABLE SATELLITE
GREENESS DATA...IT APPEARS THAT WITH THE EXCEPTION OF PORTIONS OF
EASTERN COLORADO AND ADJACENT AREAS OF NORTHWEST KANSAS WIDESPREAD
CRITICAL FUELS ARE NOT AVAILABLE.
AFTERNOON HUMIDITIES WILL FALL TO THE 10 TO 20 PERCENT RANGE EACH
AFTERNOON THROUGH FRIDAY. WINDS ARE EXPECTED TO REMAIN CRITICAL
VALUES ON THURSDAY...BUT WILL INCREASE THROUGH THE DAY FRIDAY.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...RED FLAG WARNING UNTIL 8 PM MDT /9 PM CDT/ THIS EVENING FOR
KSZ001-013-027.
CO...RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ252>254.
NE...RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR NEZ079.
&&
$$
UPDATE...DR
SHORT TERM...JRM
LONG TERM...JRM/PM
AVIATION...DR
FIRE WEATHER...JRM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
118 PM EDT WED MAY 16 2012
.SYNOPSIS...
ISSUED AT 518 AM EDT WED MAY 16 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE FROM
THE ROCKIES INTO SASK AND A DOWNSTREAM TROUGH FROM HUDSON BAY INTO
THE CNTRL GREAT LAKES RESULTING IN NW FLOW THROUGH UPPER MI. AT THE
SFC...HIGH PRES FROM MANITOBA INTO WRN MN WAS BUILDING INTO THE WRN
GREAT LAKES. SUBSIDENCE AND DRY ADVECTION IN THE WAKE OF THE MID
LEVEL TROUGH HAS BROUGHT CLEAR SKIES TO THE AREA ALONG WITH
DIMINISHING WINDS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 518 AM EDT WED MAY 16 2012
TODAY...SUNSHINE AND MIXING IN THE VERY DRY AIRMASS (PWAT VALUES
DOWN TO NEAR 0.25 INCH) OVER THE AREA WILL BOOST TEMPS INTO THE
LOWER TO MID 60S BUT PUSH DEWPOINTS DOWN TO NEAR 20 OVER INLAND
LOCATIONS THIS AFTERNOON. THIS WILL RESULT IN RH VALUES IN THE 20 TO
25 PCT RANGE. FORTUNATELY WINDS WILL BE RELATIVELY LIGHT...ONLY
INCREASING INTO THE 10 TO 15 MPH RANGE THIS AFTERNOON.
TONIGHT...AS THE MID LEVEL RIDGE EDGES TO THE EAST...DOWNSTREAM WAA
AND 300K-305K ISENTROPIC LIFT WILL BRING AN INCREASE IN MID LEVEL
CLOUDS FROM NW ONTARIO INTO UPPER MI. HOWEVER...LIGHT WINDS AND
MAINLY CLEAR SKIES TIL LATE NIGHT OVER THE EAST WILL RESULT IN
DECENT RADIATIONAL COOLING WITH TEMPS FALLING INTO THE LOWER 30S.
A FROST ADVY MAY BE NEEDED FOR THE INTERIOR EAST HALF...ESPECIALLY
IF THERE IS A TREND TOWARD LATER INCREASE IN CLOUDS.
THURSDAY...EXPECT THE POSITION OF THE 850 MB WARM FRONT AND GREATER
LOW LEVEL THETA-E ADVECTION...PER NAM/GFS/ECMWF...TO REMAIN FAR
ENOUGH TO THE SOUTH AND WEST TO KEEP BEST PCPN CHANCES OVER NRN
MN AND NRN WI. HOWEVER...SOME SHRA MAY BRUSH MAINLY THE SW PORTION
OF THE CWA. CLOUD COVER SHOULD BE THICK ENOUGH TO KEEP TEMPS INTO
THE MID TO UPPER 60S...EVEN AS 850 MB TEMPS CLIMB INTO THE 7C TO 10C
RANGE.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 518 AM EDT WED MAY 16 2012
NAM STARTS OFF WITH A 500 MB TROUGH OVER THE WESTERN U.S. AND
SHORTWAVE IN THE CENTRAL PLAINS 00Z FRI WITH RIDGING INTO THE UPPER
MISSISSIPPI RIVER VALLEY AND TROUGHING IN THE SERN U.S. AND ALSO IN
NEW ENGLAND. UPPER LEVEL RIDGING BUILDS INTO THE UPPER GREAT LAKES
THIS PERIOD.
NAM BRINGS THIS SHORTWAVE NORTHEAST FRIDAY WITH 850-500 MB Q-VECTOR
CONVERGENCE AND DEEPER MOISTURE MOVING THROUGH THE AREA BEFORE BOTH
GET PUSHED NORTH FRIDAY NIGHT. NAM ALSO SHOWS SOME ISENTROPIC LIFT
AND LIMITED MOISTURE THU NIGHT WITH A WARM FRONT MOVING THROUGH THE
AREA BEFORE THE LIFT AND MOISTURE PUSH NORTH ON FRIDAY. GFS SHOWS
ABOUT THE SAME THING FOR ISENTROPIC LIFT ON I300K-I310K SURFACES AND
MOISTURE THU NIGHT INTO FRI. GFS AND ECMWF ALSO SHOW 850-500 MB
Q-VECTOR CONVERGENCE OVER THE AREA THROUGH 12Z SAT. WILL PUT IN
CHANCE TO SLIGHT CHANCE POPS FOR THIS WARM FRONT THU NIGHT THROUGH
FRIDAY NIGHT ACROSS THE AREA. BEST CHANCES FOR PCPN WILL BE ACROSS
THE WEST AND LOWEST IN THE EAST AWAY FROM THE BETTER MOISTURE AND
DYNAMICS. DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST FOR
TEMPERATURES.
IN THE EXTENDED...ECMWF SHOWS A 500 MB RIDGE OVER THE UPPER GREAT
LAKES WITH TROUGHING IN THE WESTERN U.S. 12Z WITH A TROUGH IN THE
EASTERN U.S. AND A WEAK CLOSED 500 MB LOW OVER THE SERN U.S. PATTERN
CHANGES LITTLE 12Z SUNDAY BEFORE THE TROUGH IN THE WESTERN U.S.
MOVES INTO THE UPPER GREAT LAKES SUN NIGHT THROUGH TUE. GFS SHOWS
ABOUT THE SAME THING THROUGH SUNDAY. WHAT THIS WILL MEAN IS A VERY
WARM PERIOD AT THE START OF THE WEEKEND...THEN A COOL DOWN INTO
EARLY NEXT WEEK. TEMPERATURES WILL STILL BE AT OR ABOVE NORMAL
THOUGH. WITH THE UPPER LEVEL TROUGH REMAINING INTO TUE...AFTER
CHANCE TO LIKELY POPS ON SUNDAY WITH THE COLD FRONT...SLIGHT CHANCE
POPS FOR MONDAY INTO TUESDAY STILL SEEM WARRANTED. DID BUMP HIGHS UP
A BIT ON SATURDAY AS PLENTY OF SUNSHINE AND 850 MB TEMPERATURES TO
14C TO 16C...THIS WOULD GIVE HIGHS IN THE LOWER TO MID 80S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 117 PM EDT WED MAY 16 2012
VFR CEILINGS AND VIS EXPECTED OVER THE NEXT 24 HOURS...AS HIGH
CLOUDS INVADE FROM THE NORTHWEST. AFTERNOON GUSTS NEAR 20KTS WILL BE
POSSIBLE AT CMX AND SAW TODAY...AND WILL BE POSSIBLE MAINLY AT IWD
AND SAW WITH A SOUTHERLY PUSH ON THURSDAY.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 518 AM EDT WED MAY 16 2012
WINDS WILL BE BELOW 25 KNOTS THROUGH THE PERIOD. A HIGH PRESSURE
RIDGE WILL BUILD INTO THE REGION TODAY THROUGH THURSDAY. A LOW
PRESSURE TROUGH WILL APPROACH FROM THE PLAINS AND PUSH A WARM FRONT
ACROSS THE AREA THURSDAY NIGHT INTO FRIDAY. A COLD FRONT WILL MOVE
THROUGH THE UPPER GREAT LAKES ON SUNDAY WITH COOLER HIGH PRESSURE
BUILDING BACK IN FOR EARLY NEXT WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...07
AVIATION...KF
MARINE...07
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
315 PM EDT WED MAY 16 2012
.SYNOPSIS...
A SLOW MOVING COLD FRONT WILL BRING SHOWERS AND THUNDERSTORMS THIS
EVENING AND AGAIN ON THURSDAY. THE FRONT WILL MOVE OFF THE COAST
LATE THURSDAY AND STALL. HIGH PRESSURE WILL RIDGE INTO THE AREA
FROM THE NORTHEAST INTO EARLY NEXT WEEK WHILE LOW PRESSURE DEVELOPS
ALONG THE FRONT AND MOVES SLOWLY NE.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1:30 PM WEDNESDAY...VIGOROUS SEA BREEZE CONVECTION OVER THE
COASTAL COUNTIES NOW IN PROGRESS IS BEING CAPTURED NEARLY
PERFECTLY BY THE LOCAL HRRR MODEL. THIS SAME MODEL CONTINUES SEA
BREEZE RELATED CONVECTION INTO THE AFTERNOON HOURS...WITH ACTIVITY
SPREADING INLAND DURING THAT TIME. ACT TWO WILL BEGIN THIS EVENING
AS CONVECTION ASSOCIATED WITH A SLOW MOVING COLD FRONT SPREADS
FROM THE NORTHWEST TOWARDS THE COAST.
MODIFIED AREA SOUNDINGS FROM THIS MORNING SHOW A MOIST AND
MODERATELY UNSTABLE ATMOSPHERE WITH STEEP LAPSE RATES DEVELOPING
THIS AFTERNOON. EXTENSIVE CLOUD COVER IS KEEPING A BIT OF A DAMPER
ON CONVECTION INLAND SO FAR...ALTHOUGH CONVECTIVE TEMPERATURES
SEEM TO HAVE BEEN EXCEEDED MOST PLACES. CONVECTION ALONG THE SEA
BREEZE FRONT HAS BEEN STRONG TO MARGINALLY SEVERE SO FAR WITH
REPORTS OF FREQUENT LIGHTNING...HEAVY RAIN AND MOSTLY SMALL HAIL.
AS STATED ABOVE...APPROACHING COLD FRONT WILL TRIGGER ADDITIONAL
CONVECTION STARTING THIS EVENING FROM THE NORTHWEST. FRONT WILL
SLOWLY DROP SE ACROSS THE FORECAST AREA AND OFFSHORE BY AROUND
DAYBREAK THURSDAY. SYSTEM HAS DECENT UPPER LEVEL SUPPORT WITH AN
IMPRESSIVE VORTICITY MAXIMUM AND A MODERATELY DEEP H/5 TROUGH
ACCOMPANYING THE FRONT. THESE FEATURES WILL CONTINUE THE GOOD
CHANCE THAT CONVECTION WILL CONTINUE THROUGH THE OVERNIGHT HOURS.
BASED ON RECENT MODEL PERFORMANCE HAVE GONE ABOVE GUIDANCE FOR
OVERNIGHT TEMPERATURES. MAJOR GUIDANCE HAS BEEN CONSISTENTLY TOO
COOL LATELY...SO WILL BE GOING WITH MID 60S FOR MINIMUMS OVERNIGHT.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 PM WEDNESDAY...THURSDAY LOOKS LIKE ANOTHER DAY WHERE
SCATTERED SHOWERS AND STORMS ARE POSSIBLE AS THE FRONT MOVES SLOWLY
THROUGH BEFORE STALLING OFF THE COAST. THERE IS THE POSSIBILITY OF
SHOWERS AND STORMS AGAIN FRIDAY ALONG THE COAST...OTHERWISE FRIDAY
IS EXPECTED TO BE DRY.
TEMPS WILL REMAIN AROUND CLIMO FOR HIGHS THROUGH THE
PERIOD...REACHING A FEW DEGREES EITHER SIDE OF 80. LOWS AROUND 60
ARE EXPECTED THURSDAY NIGHT WITH MID 50S TO AROUND 60 EXPECTED
FRIDAY NIGHT.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 300 PM WEDNESDAY...SATURDAY LOOKS TO BE DRY WITH HIGH PRESSURE
RIDGING IN FROM THE NORTHEAST. HOWEVER...AN AREA OF LOW PRESSURE
ALONG AN OLD FRONT OFF THE COAST OFF THE COAST WILL BRING A RETURN
OF THE POSSIBILITY OF SHOWERS ON SUNDAY. AS WINDS BECOME MORE
EASTERLY EARLY NEXT WEEK...THE POSSIBILITY OF SHOWERS AND
THUNDERSTORMS...MAINLY OF THE AFTERNOON AND EVENING VARIETY...WILL
RETURN. MAX TEMPERATURES WILL MODERATE SLIGHTLY THROUGH THE PERIOD
FROM UPPER 70S TO LOWER 80S SATURDAY TO LOW TO MID 80S BY MID WEEK.
LOWS WILL ALSO MODERATE FROM THE MID 50S TO AROUND 60 SATURDAY NIGHT
TO LOW TO MID 60S BY TUESDAY NIGHT.
&&
.AVIATION /17Z WEDNESDAY THROUGH SUNDAY/...
AS OF 17Z...CONVECTION ALREADY FIRING ALONG THE RESULTANT...WITH
CAPES AT 2K+ AND 1.6" PRECIPITABLE WATER. CONVECTION MAY OVERPOWER
THE RESULTANT AND AFFECT THE COASTAL TERMINALS THROUGH MUCH OF THE
AFTERNOON...POSSIBLY EARLY EVENING. LOOK FOR MVFR CEILINGS AND BRIEF
IFR VISIBILITIES IN THE HEAVY RAIN. SCATTERED CONVECTION WILL ALSO
AFFECT INLAND TERMINALS...BUT CONFIDENCE IS LOWER WITH RESPECT TO
TIMING AND INTENSITY. TONIGHT...CONVECTION WILL WANE...BUT MORE
NOCTURNAL SHOWERS COULD ERUPT OFFSHORE...POSSIBLY COMING NEAR THE
MYRTLES AND ILM THROUGH THE OVERNIGHT HOURS. BRIEF IFR CEILINGS ARE
POSSIBLE AFTER 08Z WITH ABUNDANT LOW LEVEL MOISTURE.
THURSDAY...WINDS SHIFT WEAKLY TO THE NORTHEAST WITH MORE SCATTERED
CONVECTION EXPECTED...BEST CHANCE SOUTH.
EXTENDED OUTLOOK...CONDITIONS IMPROVING LATE THURSDAY NIGHT WITH VFR
EXPECTED FRIDAY THROUGH SUNDAY. CHANCE OF SHOWERS SOUTH ON MONDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1:30 PM WEDNESDAY...WINDS NEAR SHORE THIS AFTERNOON BEING
ENHANCED BY CONVECTION JUST INLAND THAT IS RELATED TO THIS
AFTERNOONS SEA BREEZE CIRCULATION. SOUTHERLY WINDS ARE RIGHT
AROUND 15 KTS NEAR SHORE...AND AROUND 20 IN THE VICINITY OF
CONVECTION. OTHERWISE...GENERALLY LIGHT SOUTH TO SOUTHWESTERLY
WINDS OVER THE WATERS WILL PRECEDE A COLD FRONT TODAY AND THIS
EVENING...WITH WINDS TURNING NEARLY CALM BY DAYBREAK AS THE FRONT
MOVES OVER THE WATERS. SEAS WILL REMAIN IN THEIR PRESENT 3 FT
RANGE THROUGH THE PERIOD...PERHAPS DROPPING A FOOT BY MORNING AS
WINDS SLACKEN.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 PM WEDNESDAY...THURSDAY IS A TRANSITION DAY AS A COLD
FRONT CROSSES THE WATERS DURING IN THE DAY. NW WINDS OF 5-10 KTS
EARLY THURSDAY WILL BECOME NE AND BEGIN TO INCREASE ON A NE SURGE AS
HIGH PRESSURE RIDGES DOWN THE COAST. WINDS INCREASE TO 10-15 KTS
THURSDAY NIGHT WHICH HELPS BUILD SEAS FROM 2-3 FT UP TO 3-4
FT...WITH THE NE WIND CHOP BECOMING INCREASINGLY MORE DOMINANT IN
THE SPECTRUM. NE WINDS INCREASE FURTHER FRIDAY...TO 15-20 KTS
THROUGH THE DAY. THIS BUILDS SEAS FURTHER...TO 4-5 FT...AND SCEC
HEADLINES MAY BE NEEDED LATE IN THE DAY.
LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 300 PM WEDNESDAY...CONTINUED STRONG E-NE WINDS THROUGH THE
WKND MAY NECESSITATE A SMALL CRAFT ADVISORY THROUGH THROUGH MUCH OF
THE WEEKEND. NE WINDS OF 15-20 KTS WILL PERSIST INTO SUNDAY BEFORE
DIMINISHING LATE SUNDAY INTO MONDAY AS WINDS BECOME MORE EASTERLY.
AS A RESULT...SEAS WILL BUILD TO 4-6 FT BEGINNING VERY EARLY
SATURDAY AND PERSISTING INTO SUNDAY. SEAS WILL SUBSIDE TO AROUND 4
FT BY MONDAY AFTERNOON.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...REK/JDW
NEAR TERM...REK
SHORT TERM...RAN
LONG TERM...RAN
AVIATION...DL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
148 PM EDT WED MAY 16 2012
.SYNOPSIS...
A SLOW MOVING COLD FRONT WILL BRING SHOWERS AND THUNDERSTORMS
AGAIN TODAY AND THIS EVENING...WITH SOME OF THESE PRODUCING VERY
HEAVY RAINFALL. SHOWERS AND THUNDERSTORMS ARE POSSIBLE AGAIN
ON THURSDAY AS A COLD FRONT LINGERS NEAR SHORE. BUILDING HIGH
PRESSURE WILL BRING DRIER AND MORE SEASONABLE WEATHER FROM FRIDAY
THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1:30 PM WEDNESDAY...VIGOROUS SEA BREEZE CONVECTION OVER THE
COASTAL COUNTIES NOW IN PROGRESS IS BEING CAPTURED NEARLY
PERFECTLY BY THE LOCAL HRRR MODEL. THIS SAME MODEL CONTINUES SEA
BREEZE RELATED CONVECTION INTO THE AFTERNOON HOURS...WITH ACTIVITY
SPREADING INLAND DURING THAT TIME. ACT TWO WILL BEGIN THIS EVENING
AS CONVECTION ASSOCIATED WITH A SLOW MOVING COLD FRONT SPREADS
FROM THE NORTHWEST TOWARDS THE COAST.
MODIFIED AREA SOUNDINGS FROM THIS MORNING SHOW A MOIST AND
MODERATELY UNSTABLE ATMOSPHERE WITH STEEP LAPSE RATES DEVELOPING
THIS AFTERNOON. EXTENSIVE CLOUD COVER IS KEEPING A BIT OF A DAMPER
ON CONVECTION INLAND SO FAR...ALTHOUGH CONVECTIVE TEMPERATURES
SEEM TO HAVE BEEN EXCEEDED MOST PLACES. CONVECTION ALONG THE SEA
BREEZE FRONT HAS BEEN STRONG TO MARGINALLY SEVERE SO FAR WITH
REPORTS OF FREQUENT LIGHTNING...HEAVY RAIN AND MOSTLY SMALL HAIL.
AS STATED ABOVE...APPROACHING COLD FRONT WILL TRIGGER ADDITIONAL
CONVECTION STARTING THIS EVENING FROM THE NORTHWEST. FRONT WILL
SLOWLY DROP SE ACROSS THE FORECAST AREA AND OFFSHORE BY AROUND
DAYBREAK THURSDAY. SYSTEM HAS DECENT UPPER LEVEL SUPPORT WITH AN
IMPRESSIVE VORTICITY MAXIMUM AND A MODERATELY DEEP H/5 TROUGH
ACCOMPANYING THE FRONT. THESE FEATURES WILL CONTINUE THE GOOD
CHANCE THAT CONVECTION WILL CONTINUE THROUGH THE OVERNIGHT HOURS.
BASED ON RECENT MODEL PERFORMANCE HAVE GONE ABOVE GUIDANCE FOR
OVERNIGHT TEMPERATURES. MAJOR GUIDANCE HAS BEEN CONSISTENTLY TOO
COOL LATELY...SO WILL BE GOING WITH MID 60S FOR MINIMUMS OVERNIGHT.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 AM WEDNESDAY...SLIGHTLY SLOWER EVOLUTION AS DEPICTED IN
GUIDANCE NOW SUGGESTS THAT THURSDAY WILL BE THE TRANSITION DAY AS
COLD FRONT...FINALLY...PUSHES OFFSHORE. PERSISTENT UPPER TROUGH
NEVER QUITE MOVES AWAY HOWEVER...AND INSTEAD ADOPTS AN ORIENTATION
MORE WSW-TO-ENE ACROSS THE SOUTHEAST AND BACK TOWARDS THE MS VLY. AT
THE SAME TIME...AN ARC OF RIDGING DEVELOPS NORTH OF THIS FEATURE
FROM THE OH VLY INTO THE MID-ATLANTIC. WITH WEAK OVERALL FORCING AND
A MORE ZONALLY DRIVEN SETUP AT 500MB...FEATURES WILL CONTINUE TO BE
QUITE SLOW TO MOVE...KEEPING AT LEAST THE POTENTIAL FOR UNSETTLED
WEATHER THROUGH THE PERIOD.
AT THE SURFACE...A COLD FRONT WILL DROP SOUTH THROUGH THE CWA EARLY
THURSDAY...BUT IS NOW PROGGED TO HANG UP AND STALL ACROSS SOUTHERN
AND COASTAL PORTIONS OF THE CWA. THIS WILL AGAIN SERVE AS A FOCUS
FOR CONVECTION...ALTHOUGH POSSIBLY SPARING INLAND LOCATIONS THAT
HAVE SEEN SIGNIFICANT RAINFALL THE PAST FEW DAYS. WILL CARRY CHC POP
THURSDAY ALONG THE COAST AND SC ZONES...WITH SCHC INLAND/NC
COUNTIES. THIS FRONT WILL PUSH ONLY SLIGHTLY FURTHER SOUTH FRIDAY AS
SURFACE HIGH RIDGES DOWN FROM THE NORTH. EVEN THOUGH THE FRONT WILL
REMAIN INVOF THIS AREA...MUCH DRIER AIR NOTED IN FORECAST SOUNDINGS
SUGGESTS THAT FRIDAY WILL BE A DRY DAY SO WILL KEEP POP SILENT
FRIDAY.
TEMPS WILL REMAIN AROUND CLIMO FOR HIGHS AND LOWS THROUGH THE
PERIOD...A FEW DEGREES EITHER SIDE OF 80 AND 60.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 300 AM WEDNESDAY...GUIDANCE COMING INTO BETTER AGREEMENT FOR
THE WKND WITH A RESIDUAL E-W ORIENTED 500MB TROUGH PERSISTING ACROSS
THE SOUTHEAST...WHILE A RIDGE DEVELOPS NORTH OF THIS FROM THE OH VLY
INTO THE MID ATLANTIC. AT THE SURFACE...A STALLED STATIONARY FRONT
WILL BE DRAPED JUST OFF THE COAST AND BACK INTO NORTHERN
FLORIDA...WHILE A RIDGE OF HIGH PRESSURE PUSHES NE DOWN THE COAST.
EVEN WITH THE FRONT REMAINING NEAR THE AREA...EXPECT THE WKND TO BE
DRY. THE RIDGE OF HIGH PRESSURE WILL PROMOTE A SUBTLE SUBSIDENCE
INVERSION NEAR THE SURFACE WHILE DRIER AIR REMAINS IN THE MID
LEVELS. WILL KEEP POP JUST BELOW THRESHOLD NEAR THE COAST TO ACCOUNT
FOR THE BOUNDARY OFFSHORE...BUT EXPECT NO SHOWERS THROUGH THE WKND.
AS SURFACE HIGH DRIFTS OFF THE NEW ENGLAND COAST MON/TUE...SURFACE
FLOW BECOMES MORE EASTERLY WHICH INCREASES MOISTURE ADVECTION INTO
THE COLUMN. ADDITIONALLY...THICKNESSES BEGIN TO RETURN TO MORE
SEASONABLE LEVELS AS PERSISTENT TROUGHING FINALLY BEGINS TO ERODE.
THIS COULD ALLOW FOR DIURNAL SHOWERS TO RETURN MON/TUE AND WILL
CARRY SCHC BEING SO FAR OUT.
TEMPS THROUGH THE PERIOD WILL BE AROUND CLIMO FOR MAXES AND
MINS...BECOMING SLIGHTLY ABOVE AT THE END OF THE PERIOD.
&&
.AVIATION /17Z WEDNESDAY THROUGH SUNDAY/...
AS OF 17Z...CONVECTION ALREADY FIRING ALONG THE RESULTANT...WITH
CAPES AT 2K+ AND 1.6" PRECIPITABLE WATER. CONVECTION MAY OVERPOWER
THE RESULTANT AND AFFECT THE COASTAL TERMINALS THROUGH MUCH OF THE
AFTERNOON...POSSIBLY EARLY EVENING. LOOK FOR MVFR CEILINGS AND BRIEF
IFR VISIBILITIES IN THE HEAVY RAIN. SCATTERED CONVECTION WILL ALSO
AFFECT INLAND TERMINALS...BUT CONFIDENCE IS LOWER WITH RESPECT TO
TIMING AND INTENSITY. TONIGHT...CONVECTION WILL WANE...BUT MORE
NOCTURNAL SHOWERS COULD ERUPT OFFSHORE...POSSIBLY COMING NEAR THE
MYRTLES AND ILM THROUGH THE OVERNIGHT HOURS. BRIEF IFR CEILINGS ARE
POSSIBLE AFTER 08Z WITH ABUNDANT LOW LEVEL MOISTURE.
THURSDAY...WINDS SHIFT WEAKLY TO THE NORTHEAST WITH MORE SCATTERED
CONVECTION EXPECTED...BEST CHANCE SOUTH.
EXTENDED OUTLOOK...CONDITIONS IMPROVING LATE THURSDAY NIGHT WITH VFR
EXPECTED FRIDAY THROUGH SUNDAY. CHANCE OF SHOWERS SOUTH ON MONDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1:30 PM WEDNESDAY...WINDS NEAR SHORE THIS AFTERNOON BEING
ENHANCED BY CONVECTION JUST INLAND THAT IS RELATED TO THIS
AFTERNOONS SEA BREEZE CIRCULATION. SOUTHERLY WINDS ARE RIGHT
AROUND 15 KTS NEAR SHORE...AND AROUND 20 IN THE VICINITY OF
CONVECTION. OTHERWISE...GENERALLY LIGHT SOUTH TO SOUTHWESTERLY
WINDS OVER THE WATERS WILL PRECEDE A COLD FRONT TODAY AND THIS
EVENING...WITH WINDS TURNING NEARLY CALM BY DAYBREAK AS THE FRONT
MOVES OVER THE WATERS. SEAS WILL REMAIN IN THEIR PRESENT 3 FT
RANGE THROUGH THE PERIOD...PERHAPS DROPPING A FOOT BY MORNING AS
WINDS SLACKEN.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 AM WEDNESDAY...THURSDAY IS A TRANSITION DAY AS A COLD
FRONT CROSSES THE WATERS EARLY IN THE DAY. NW WINDS OF 5-10 KTS
EARLY THURSDAY WILL BECOME NE LATE IN THE DAY AND BEGIN TO INCREASE
ON A NE SURGE AS HIGH PRESSURE RIDGES DOWN THE COAST. WINDS INCREASE
TO 10-15 KTS THURSDAY NIGHT WHICH HELPS BUILD SEAS FROM 2-3 FT UP TO
3-4 FT...WITH THE NE WIND CHOP BECOMING INCREASINGLY MORE DOMINANT
IN THE SPECTRUM. NE WINDS INCREASE FURTHER FRIDAY...TO 15-20 KTS
THROUGH THE DAY. THIS BUILDS SEAS FURTHER...TO 4-5 FT...AND SCEC
HEADLINES MAY BE NEEDED LATE IN THE DAY.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 300 AM WEDNESDAY...CONTINUED STRONG NE WINDS THROUGH THE WKND
WILL LIKELY NECESSITATE A SMALL CRAFT ADVISORY THROUGH THE ENTIRE
EXTENDED. NE WINDS OF 15-20 KTS WILL PERSIST THROUGH THE WKND WITH
ONLY MINOR DIURNAL VARIATIONS. THIS BUILDS SEAS TO 4-6 FT BEGINNING
VERY EARLY SATURDAY AND PERSISTING THROUGH SUNDAY NIGHT...WITH A
6SEC NE WIND WAVE BEING THE DOMINANT FEATURE IN THE SEA SPECTRUM. AS
IS FREQUENTLY THE CASE WITH NE SURGES...THE HIGHEST SEAS WILL BE
BLOCKED BY THE FRYING PAN SHOALS...SO A SHADOW REGION OF 2-4 FT SEAS
IN THE INNER 10NM ALONG BRUNSWICK AND NORTHERN HORRY COUNTIES WILL
EXIST THROUGH THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...REK/JDW
NEAR TERM...REK
SHORT TERM...JDW
LONG TERM...JDW
AVIATION...DL
MARINE...REK/JDW
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
119 PM EDT WED MAY 16 2012
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE NORTHWEST TODAY AND MOVE
THROUGH THE REGION LATE TONIGHT. HIGH PRESSURE WILL BUILD IN FROM
THE NORTH BEHIND THE FRONT AND CONTINUE TO RIDGE INTO THE AREA
THIS WEEKEND AS AN AREA OF LOW PRESSURE LIFTS NORTH OFFSHORE.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 110 PM WED...MADE MINOR ADJUSTMENTS TO REFLECT CURRENT
TRENDS. THIS POSITIVELY TILTED UPPER LEVEL TROUGH WILL PERSIST ACROSS
THE APPALACHIANS INTO THE DEEP SOUTH WHILE A DISSIPATING TROUGH OF
LOW PRES CONTINUES ACROSS THE CAROLINA PIEDMONT REGION. ATMOSPHERE
CONDITIONS CONTINUE TO BE VERY MOIST AND UNSTABLE WITH CURRENT
CAPE VALUES IN 2500 ACROSS THE SOUTHERN COASTAL PLAINS AND LI OF
-7. BOTH SPC MESO ANALYSIS AND RUC MODEL REFLECTS PERFECTLY WHAT
IS HAPPENING ON RADAR. RADAR IS CURRENTLY SHOWING SHOWERS AND
THUNDERSTORMS ALONG OR EAST OF HWY 17 AND WILL CONTINUE INTO THE
EVENING. HIGHS TODAY GENERALLY IN THE L80S INLAND AND U70S ALONG
THE COAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
AS OF 315 AM WED...A ROBUST NRN STREAM SHORTWAVE TROUGH SLIDES E
OF THE GREAT LAKES TODAY AND MOVES INTO NEW ENGLAND TONIGHT WHILE
THE ATTENDANT COLD FRONT DROPS ACROSS THE OHIO RIVER VALLEY TODAY
AND IS EXPECTED TO PUSH THROUGH ERN NC LATE TONIGHT. ONGOING
SHOWERS AND TSTMS EARLY THIS EVENING SHOULD DISSIPATE WITH LOSS OF
SFC HEATING BUT THE AIRMASS REMAINS CONDITIONALLY UNSTABLE AND
FRONTAL FORCING COULD BRING ADDITIONAL SHOWERS OR STORMS ACROSS
THE REGION OVERNIGHT. SWLY FLOW AHEAD OF THE FRONT WILL BRING
ANOTHER MILD NIGHT WITH LOWS MAINLY IN THE M/U60S.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
AS OF 315 AM WEDNESDAY...ENOUGH MODEL AGREEMENT TO MAKE MINOR
ADJUSTMENTS TO THU-FRI PERIOD...THEN MODELS DIVERGE ON PATTERN
EVOLUTION...LEADING TO LOW CONFIDENCE FCST FOR SAT-TUE.
SFC FRONT WILL BE MOVING OFF COAST EARLY THU...BUT CAA AND LINGERING
UPR TROF ENERGY SUPPORT PSBL SHOWER/TSTM DEVELOPMENT WITH ALL MODELS
INDICATING SOME LIGHT QPF. ADJUSTED FCST FOR 20N/40S POPS DURING THE
DAY...WITH LINGERING 20/30 SRN COASTAL SECTIONS THU NIGHT...IN LINE
WITH MOS POP BLEND. MODELS GENERALLY AGREE ON DRY FCST FOR FRI AND
FRI NIGHT WITH DRYING ATMOS AND UPR TROF AXIS MOVING OFF COAST.
00Z GFS HAS MAINLY DRY FCST FOR WEEKEND WITH SE UPR LOW SUPPRESSED
FARTHER S...WHILE 00Z ECMWF CONTINUES TO INDICATE UPR LOW AXIS
STRETCHED SW TO NE...WITH OFFSHORE SFC LOW DEVELOPMENT GRADUALLY
RETROGRADING BACK TOWARD COAST SUN. NOT ENOUGH CONFIDENCE TO MAKE
ADJUSTMENTS TO PREVIOUS FCST...AND CONTINUED WITH LOW CHC POPS
RETURNING FOR SUN-TUE.
COOLER HIGH PRES WILL RESULT IN TEMPS MAINLY 50S/70S FOR
THU-FRI...WITH SOME GRADUAL MODERATION REST OF PERIOD.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
SHORT TERM /THROUGH TONIGHT/...
AS OF 1020 AM WED...SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS
EXPECTED AGAIN TODAY WITH A MOIST AND UNSTABLE AIRMASS IN PLACE
AND A WEAK UPPER LEVEL DISTURBANCE MOVING ACROSS THE AREA. SHOWERS
TAPER OFF THIS EVENING BUT CANNOT RULE OUT ISOLATED TO SCATTERED
SHOWERS PERSISTING OVERNIGHT WITH DESCENT INSTABILITY ALOFT AND A
COLD FRONT DROPPING INTO THE AREA LATE. ALSO CANNOT RULE OUT
PATCHY FOG LATE TONIGHT WITH ABUNDANT LOW LEVEL
MOISTURE...ESPECIALLY IN AREAS THAT RECEIVE SIGNIFICANT RAINFALL
TODAY.
LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 315 AM WEDNESDAY...COLD FRONT WILL BE MOVING OFF COAST EARLY
THU BUT DEVELOPING NE FLOW LIKELY TO CONTINUE MVFR CONDITIONS WITH
SCT SHOWERS/TSTMS DURING DAY THU AND WITH SOME STRATUS/SCU THU
NIGHT. VFR EXPECTED TO RETURN ON FRI WITH HIGH PRES BUILDING IN FROM
N...AND CONTINUE THROUGH SAT. CHC OF SHOWERS/TSTMS MAY DEVELOP
AGAIN SUN WITH INCREASING ONSHORE FLOW.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 110 PM WED...CURRENT FORECAST IS IN GREAT SHAPE. NO CHANGES
NEEDED FOR THIS AFTERNOON.
PREV DISC...S/SWLY WINDS AOB 15 KT CONTINUE TODAY WITH HIGH PRES
CENTERED OFFSHORE AND A DISSIPATING TROUGH INLAND AND A COLD FRONT
APPROACHING FROM THE NW. SEAS GRADUALLY DISSIPATING EARLY THIS
MORNING AND BUOY 44095 OFF OREGON INLET HAS DROPPED BELOW 6 FT
OVER THE PAST COUPLE HOURS AND EXPECT THE TREND TO CONTINUE AND
WILL DROP THE SCA. SEAS AROUND 2-5 FT EXPECTED TODAY AND TONIGHT.
LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 315 AM WEDNESDAY...MODELS CONTINUE TO SUPPORT CAA SURGE OF NE
WINDS 15-20 KT SPREADING N TO S ALONG COAST ON THU AS HIGH PRES
BUILDS ACROSS TO N. NE WINDS EXPECTED TO PERSIST THROUGH WEEKEND BUT
LOW CONFIDENCE ON SPEEDS BEYOND FRIDAY DUE TO MODEL DIFFERENCES ON
STRENGTH OF PRES GRADIENT. ALL MODELS GENERALLY AGREE TO HIGH PRES
WILL CONTINUE TO EXTEND OVER AREA FROM MID ATLC COAST...BUT NAM AND
ECMWF HAVE LOW PRES DEVELOPING OFFSHORE AND MOVING TOWARD COAST
DURING PERIOD RESULTING IN MUCH STRONGER WINDS. HAVE LEANED TO GFS
AND PREVIOUS FCST FOR WEEKEND...WITH PERSISTENT NE 15-20 KT FLOW
LIKELY TO PRODUCE 5-6 FT SEAS FRIDAY-SUNDAY. STRONGER ECMWF AND NAM
SOLUTIONS WOULD OBVIOUSLY RESULT IN PERIOD OF HIGHER WINDS AND
SEAS...ESPECIALLY FOR NORTHERN AND CENTRAL WATERS.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SK
NEAR TERM...SK/BM
SHORT TERM...SK
LONG TERM...JBM
AVIATION...JBM/HSA/SK
MARINE...JBM/SK/BM
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1225 PM EDT WED MAY 16 2012
.SYNOPSIS...
A SLOW MOVING COLD FRONT WILL BRING SHOWERS AND THUNDERSTORMS AGAIN
TODAY...WITH SOME OF THESE PRODUCING VERY HEAVY RAINFALL. SHOWERS
AND THUNDERSTORMS ARE POSSIBLE AGAIN THURSDAY AS AN APPROACHING COLD
FRONT FINALLY PUSHES OFFSHORE. BUILDING HIGH PRESSURE WILL BRING
DRIER AND MORE SEASONABLE WEATHER FRIDAY THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 10:30 AM WEDNESDAY...ANALYSIS OF MORNING SOUNDINGS CONFIRM
EARLIER HYPOTHESIS THAT TODAY WILL FEATURE ANOTHER ROUND OF
DIURNALLY-DRIVEN CONVECTION. MOIST SOUTHWESTERLY FLOW WILL REMAIN
IN PLACE WITH P/W VALUES OF AROUND 1.50 INCHES AND DEWPOINTS WELL
IN THE 60S. MODEL SOUNDINGS DEVELOP MODERATE INSTABILITY WITH
STEEP LAPSE RATES ACROSS THE AREA THIS AFTERNOON. PEAK
DESTABILIZATION WILL THUS BE THIS AFTERNOON...WHEN THE GREATEST
THREAT OF STRONG CONVECTION WILL BE. UNTIL THEN...EXPECT INITIAL
CONVECTION TO FIRE UP ALONG A WEAK SEA BREEZE BOUNDARY LATE THIS
MORNING AND EARLY AFTERNOON. HRRR MODEL DID FAIRLY WELL DEPICTING
THIS YESTERDAY...AND IS GOING FOR A REPEAT PERFORMANCE TODAY.
PREVIOUS DISCUSSION FOLLOWS:
INGREDIENTS COALESCING FOR ANOTHER ROUND OF DIURNAL THUNDERSTORMS
AS HEATING DESTABILIZES A MOISTURE RICH COLUMN. WEAK OUTFLOW
BOUNDARIES SNAKING ACROSS THE REGION EARLY THIS MORNING WILL
PRODUCE ISOLATED HEAVY THUNDERSHOWERS EVEN PRIOR TO DIURNAL
WARMING. THE SEA BREEZE BOUNDARY WILL PROVIDE A FOCUS FOR A BROKEN
LINE OF THUNDERSTORMS TO LIGHT UP BY EARLY AFTERNOON ACROSS OUR
COASTAL INTERIOR. UPPER WINDS MAY PUSH THE CONVECTION BACK TOWARD
THE COAST IN THE LATE AFTERNOON AND EVENING.
PRECIPITABLE WATER VALUES BETWEEN 1.3-1.5 ACROSS THE REGION AND
DEWPOINTS OF 66-71...WILL INTERACT WITH SHARPENING LOW-LEVEL LAPSE
RATES BY MID AFTERNOON TO PRODUCE AN ISOLATED POTENTIAL FOR STRONG
WIND GUSTS OR DAMAGING WINDS.
PLENTIFUL CLOUDS WILL KEEP MAX TEMPS HELD IN THE LOWER TO MIDDLE
80S TODAY. A COLD FRONT WILL EXIT THE MOUNTAINS TODAY AND MOVE TO
THE COAST LATE TONIGHT INTO DAYBREAK THURSDAY. FOR THIS REASON
MENTIONABLE POP VALUES WERE RETAINED TROUGH THE OVERNIGHT PERIOD.
MINIMUM TEMPS AS A RESULT SHOULD BE JUST A DEGREE OR TWO COOLER
THAN THE LAST FEW MORNINGS.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 AM WEDNESDAY...SLIGHTLY SLOWER EVOLUTION AS DEPICTED IN
GUIDANCE NOW SUGGESTS THAT THURSDAY WILL BE THE TRANSITION DAY AS
COLD FRONT...FINALLY...PUSHES OFFSHORE. PERSISTENT UPPER TROUGH
NEVER QUITE MOVES AWAY HOWEVER...AND INSTEAD ADOPTS AN ORIENTATION
MORE WSW-TO-ENE ACROSS THE SOUTHEAST AND BACK TOWARDS THE MS VLY. AT
THE SAME TIME...AN ARC OF RIDGING DEVELOPS NORTH OF THIS FEATURE
FROM THE OH VLY INTO THE MID-ATLANTIC. WITH WEAK OVERALL FORCING AND
A MORE ZONALLY DRIVEN SETUP AT 500MB...FEATURES WILL CONTINUE TO BE
QUITE SLOW TO MOVE...KEEPING AT LEAST THE POTENTIAL FOR UNSETTLED
WEATHER THROUGH THE PERIOD.
AT THE SURFACE...A COLD FRONT WILL DROP SOUTH THROUGH THE CWA EARLY
THURSDAY...BUT IS NOW PROGGED TO HANG UP AND STALL ACROSS SOUTHERN
AND COASTAL PORTIONS OF THE CWA. THIS WILL AGAIN SERVE AS A FOCUS
FOR CONVECTION...ALTHOUGH POSSIBLY SPARING INLAND LOCATIONS THAT
HAVE SEEN SIGNIFICANT RAINFALL THE PAST FEW DAYS. WILL CARRY CHC POP
THURSDAY ALONG THE COAST AND SC ZONES...WITH SCHC INLAND/NC
COUNTIES. THIS FRONT WILL PUSH ONLY SLIGHTLY FURTHER SOUTH FRIDAY AS
SURFACE HIGH RIDGES DOWN FROM THE NORTH. EVEN THOUGH THE FRONT WILL
REMAIN INVOF THIS AREA...MUCH DRIER AIR NOTED IN FORECAST SOUNDINGS
SUGGESTS THAT FRIDAY WILL BE A DRY DAY SO WILL KEEP POP SILENT
FRIDAY.
TEMPS WILL REMAIN AROUND CLIMO FOR HIGHS AND LOWS THROUGH THE
PERIOD...A FEW DEGREES EITHER SIDE OF 80 AND 60.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 300 AM WEDNESDAY...GUIDANCE COMING INTO BETTER AGREEMENT FOR
THE WKND WITH A RESIDUAL E-W ORIENTED 500MB TROUGH PERSISTING ACROSS
THE SOUTHEAST...WHILE A RIDGE DEVELOPS NORTH OF THIS FROM THE OH VLY
INTO THE MID ATLANTIC. AT THE SURFACE...A STALLED STATIONARY FRONT
WILL BE DRAPED JUST OFF THE COAST AND BACK INTO NORTHERN
FLORIDA...WHILE A RIDGE OF HIGH PRESSURE PUSHES NE DOWN THE COAST.
EVEN WITH THE FRONT REMAINING NEAR THE AREA...EXPECT THE WKND TO BE
DRY. THE RIDGE OF HIGH PRESSURE WILL PROMOTE A SUBTLE SUBSIDENCE
INVERSION NEAR THE SURFACE WHILE DRIER AIR REMAINS IN THE MID
LEVELS. WILL KEEP POP JUST BELOW THRESHOLD NEAR THE COAST TO ACCOUNT
FOR THE BOUNDARY OFFSHORE...BUT EXPECT NO SHOWERS THROUGH THE WKND.
AS SURFACE HIGH DRIFTS OFF THE NEW ENGLAND COAST MON/TUE...SURFACE
FLOW BECOMES MORE EASTERLY WHICH INCREASES MOISTURE ADVECTION INTO
THE COLUMN. ADDITIONALLY...THICKNESSES BEGIN TO RETURN TO MORE
SEASONABLE LEVELS AS PERSISTENT TROUGHING FINALLY BEGINS TO ERODE.
THIS COULD ALLOW FOR DIURNAL SHOWERS TO RETURN MON/TUE AND WILL
CARRY SCHC BEING SO FAR OUT.
TEMPS THROUGH THE PERIOD WILL BE AROUND CLIMO FOR MAXES AND
MINS...BECOMING SLIGHTLY ABOVE AT THE END OF THE PERIOD.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 17Z...CONVECTION ALREADY FIRING ALONG THE RESULTANT...WITH
CAPES AT 2K+ AND 1.6" PRECIPITABLE WATER. CONVECTION MAY OVERPOWER
THE RESULTANT AND AFFECT THE COASTAL TERMINALS THROUGH MUCH OF THE
AFTERNOON...POSSIBLY EARLY EVENING. LOOK FOR MVFR CEILINGS AND BRIEF
IFR VISIBILITIES IN THE HEAVY RAIN. SCATTERED CONVECTION WILL ALSO
AFFECT INLAND TERMINALS...BUT CONFIDENCE IS LOWER WITH RESPECT TO
TIMING AND INTENSITY. TONIGHT...CONVECTION WILL WANE...BUT MORE
NOCTURNAL SHOWERS COULD ERUPT OFFSHORE...POSSIBLY COMING NEAR THE
MYRTLES AND ILM THROUGH THE OVERNIGHT HOURS. BRIEF IFR CEILINGS ARE
POSSIBLE AFTER 08Z WITH ABUNDANT LOW LEVEL MOISTURE.
THURSDAY...WINDS SHIFT WEAKLY TO THE NORTHEAST WITH MORE SCATTERED
CONVECTION EXPECTED...BEST CHANCE SOUTH.
EXTENDED OUTLOOK...CONDITIONS IMPROVING LATE THURSDAY NIGHT WITH VFR
EXPECTED FRIDAY THROUGH SUNDAY. CHANCE OF SHOWERS SOUTH ON MONDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 10:30 AM WEDNESDAY...LATEST OBS SHOWS SOUTHERLY WINDS IN THE
10 KT RANGE...WITH SEAS OF AROUND 3 FT. THIS IS RIGHT AS FORECAST
FOR THIS TIME OF DAY. PREVIOUS DISCUSSION STILL APPLIES AND FOLLOWS
BELOW:
SEA HEIGHTS AND SYNOPTIC WINDS WILL NOT POSE A THREAT TODAY...BUT
ISOLATED TO SCATTERED THUNDERSTORMS MAY PRODUCE TREACHEROUS
CONDITIONS LOCALLY...LATER TODAY AND TONIGHT AS A WEAK COLD FRONT
APPROACHES THE COAST. MARINERS SHOULD CONSULT RADAR TRENDS BEFORE
HEADING OUT TO ASCERTAIN THE LOCAL RISKS. ELSE-WISE...SEAS
GENERALLY COMPOSED OF SE WAVES 3-4 FEET IN 7 SECONDS INTERVALS
WITH A LIGHT SSW CHOP. WINDS AND WIND-WAVES IN AND NEAR TSTMS WILL
BE LOCALLY MUCH HIGHER. WINDS TO SHIFT TO NW BUT OVERALL LIGHT
WIND-SPEEDS IN THE PRE-DAWN HOURS OF THU AS A WEAK COLD FRONT
MOVES OFFSHORE BY SUNRISE.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 AM WEDNESDAY...THURSDAY IS A TRANSITION DAY AS A COLD
FRONT CROSSES THE WATERS EARLY IN THE DAY. NW WINDS OF 5-10 KTS
EARLY THURSDAY WILL BECOME NE LATE IN THE DAY AND BEGIN TO INCREASE
ON A NE SURGE AS HIGH PRESSURE RIDGES DOWN THE COAST. WINDS INCREASE
TO 10-15 KTS THURSDAY NIGHT WHICH HELPS BUILD SEAS FROM 2-3 FT UP TO
3-4 FT...WITH THE NE WIND CHOP BECOMING INCREASINGLY MORE DOMINANT
IN THE SPECTRUM. NE WINDS INCREASE FURTHER FRIDAY...TO 15-20 KTS
THROUGH THE DAY. THIS BUILDS SEAS FURTHER...TO 4-5 FT...AND SCEC
HEADLINES MAY BE NEEDED LATE IN THE DAY.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 300 AM WEDNESDAY...CONTINUED STRONG NE WINDS THROUGH THE WKND
WILL LIKELY NECESSITATE A SMALL CRAFT ADVISORY THROUGH THE ENTIRE
EXTENDED. NE WINDS OF 15-20 KTS WILL PERSIST THROUGH THE WKND WITH
ONLY MINOR DIURNAL VARIATIONS. THIS BUILDS SEAS TO 4-6 FT BEGINNING
VERY EARLY SATURDAY AND PERSISTING THROUGH SUNDAY NIGHT...WITH A
6SEC NE WIND WAVE BEING THE DOMINANT FEATURE IN THE SEA SPECTRUM. AS
IS FREQUENTLY THE CASE WITH NE SURGES...THE HIGHEST SEAS WILL BE
BLOCKED BY THE FRYING PAN SHOALS...SO A SHADOW REGION OF 2-4 FT SEAS
IN THE INNER 10NM ALONG BRUNSWICK AND NORTHERN HORRY COUNTIES WILL
EXIST THROUGH THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JDW
NEAR TERM...MJC/REK
SHORT TERM...JDW
LONG TERM...JDW
AVIATION...43
MARINE...MJC/REK/JDW
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
400 PM EDT WED MAY 16 2012
.SYNOPSIS...
A WEAK COLD FRONT WILL DROP SOUTH THROUGH THE AREA THIS EVENING
OFFERING A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS EARLY. HIGH
PRESSURE WILL BUILD INTO THE REGION PROVIDING DRY WEATHER THROUGH
THE REMAINDER OF THE WEEK. TEMPERATURES WILL GRADUALLY WARM TO ABOVE
NORMAL BY FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
UPPER LEVEL TROF TO PIVOT EAST THRU THE GREAT LAKES INTO NEW
ENGLAND/SE CANADA BY THURSDAY MORNING. ASSOCIATED COLD FRONT WHICH
EXTENDS FROM WESTERN PA THRU SW OHIO AND SRN INDIANA TO DROP
SOUTH OF THE OHIO RIVER BY LATE AFTERNOON. BOTH NAM/GFS APPEAR
OVERDONE WITH SURFACE DEWPOINTS POOLED IN THE MID 60S ALONG AND
SOUTH OF THE FRONTAL BOUNDARY. 13 KM RAP MODEL SOLN LOOKS MORE
REALISTIC WITH DEWPOINTS IN THE UPPER 50S YIELDING MARGINAL BLYR
CAPES LESS THAN 1000 J/KG ACRS SE OHIO AND NRN KY. WL CONTINUE TO
LIMIT POPS TO SLIGHT CHANCE FOR THUNDERSTORMS ACRS THESE AREAS
EARLY. SINCE CONVECTION IS STARTING TO DEVELOP WILL OPT FOR AREAL
COVERAGE WORDING...ISOLATED THUNDERSTORMS.
IN THE WAKE OF THIS FRONT SFC HIGH PRESSURE BUILDS INTO THE GREAT
LAKES OVERNIGHT. SUBSIDENCE WILL LEAD TO CLEARING SKIES. DRY AIRMASS
AND LOW LEVEL CAA WILL LEAD TO BELOW NORMAL TEMPERATURES. HAVE FCST
LOWS RANGING FROM NEAR 40 NE TO LOWER 50S FAR SOUTH.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
SURFACE HIGH PRESSURE TO BUILD ACROSS THE GREAT LAKES ON THURSDAY.
DRY AIRMASS WILL RESULT IN MOSTLY SUNNY SKY CONDITIONS. EXPECT TEMPS
TO BE SLIGHTLY BELOW NORMAL. AFTER A COOL START TO THE DAY EXPECT
HIGHS TO RANGE FROM NEAR 70 NE TO THE MID 70S SW.
SURFACE HIGH PRESSURE TO SLIDE OFF TO THE EAST THURSDAY NIGHT.
EXPECT MAINLY CLEAR SKIES WITH ONLY SOME THIN HIGH LEVEL CLOUDS
SPILLING IN. HAVE FCST TEMPS RANGING FROM MID 40S NORTHEAST TO THE
LOWER 50S SOUTH.
MID/UPR LEVEL RIDGE TO BUILD INTO OHIO ON FRIDAY. EXPECT TO SEE A
GOOD DEAL OF SUNSHINE WITH JUST SOME HIGH LEVEL CLOUDINESS. UNDER
THE INFLUENCE OF WAA TEMPS WILL WARM TO VALUES ABOVE NORMAL. HAVE
FCST HIGHS FROM NEAR 80 NORTH TO THE LOWER 80S SOUTH.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
WITH AN UPPER RIDGE BUILDING OVERHEAD AND SURFACE HIGH PRESSURE
CENTERED TO THE EAST...A PERIOD OF DRY WEATHER IS INDICATED FOR
SATURDAY THROUGH MONDAY. CONFIDENCE IS RATHER HIGH FOR THIS TIME
FRAME DUE TO MODEL CONSISTENCY FROM RUN TO RUN.
AN UPPER LOW IS SHOWN TO DEVELOP OVER THE MISSISSIPPI VALLEY ON
TUESDAY...ACCOMPANIED BY INCREASING MOISTURE. THE LOW IS FORECAST TO
MOVE TO INDIANA ON WEDNESDAY. MODELS HAVE BEEN INCONSISTENT WITH THE
PATH OF THE UPPER LOW...MAKING THIS PART OF THE FORECAST LESS
CERTAIN. WENT WITH A CHANCE OF THUNDERSTORMS IN WESTERN COUNTIES ON
TUESDAY...EXPANDING TO THE WHOLE AREA ON WEDNESDAY.
WITH THE AREA IN A SOUTHERLY FLOW AND WITH CONSIDERABLE SUNSHINE TO
START...TEMPERATURES WILL BE ABOVE NORMAL THROUGH THE PERIOD. HIGHS
WILL BE MAINLY IN THE 80S SATURDAY THROUGH MONDAY...WITH INCREASING
CLOUDS AND POSSIBLE PRECIPITATION CAUSING READINGS TO SLIP TO THE
MID AND UPPER 70S BY WEDNESDAY.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
A WEAK COLD FRONT WILL SLIP SOUTH OF THE OHIO RIVER BY THIS
EVENING. LIMITED MOISTURE WITH THE FRONT MAY BRING AN ISOLATED
SHOWER OR THUNDERSTORM BEFORE PASSAGE. AFTER PASSAGE...MAINLY
CLEAR SKIES ARE EXPECTED. WINDS WILL VEER TO THE NORTH AND WILL BE
LOCALLY GUSTY WITH FRONTAL PASSAGE. HIGH PRESSURE IS EXPECTED TO
BUILD SOUTH INTO THE GREAT LAKES AND OHIO VALLEY THROUGH THURSDAY.
WINDS WILL VEER TO AN EASTERLY DIRECTION AND WILL RANGE BETWEEN 8
AND 14 KNOTS ON THURSDAY.
OUTLOOK...NO SIGNIFICANT WEATHER EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...AR
NEAR TERM...AR
SHORT TERM...AR
LONG TERM...CONIGLIO
AVIATION...HICKMAN
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
145 PM EDT WED MAY 16 2012
.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE THROUGH THE AREA ON WEDNESDAY. HIGH
PRESSURE WILL THEN BUILD IN FOR THE REST OF THE WEEK...WITH
GRADUALLY WARMING TEMPERATURES INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
A WEAK COLD FRONT WILL DROP SOUTHWARD THROUGH THE REGION THIS
AFTERNOON. THE FRONT SEEMS TO BE JUST A TAD SLOWER THAN PREVIOUSLY
FORECAST. FORECAST CHALLENGES WITH THIS FRONT REVOLVE AROUND
CHANCES OF PCPN AND TEMPERATURES. FORCING IS WEAK WITH THE FRONT.
ALSO...INSTABILITY WILL BE LIMITED...MORE SO THAN WHAT THE NAM-WRF
AND GFS ARE INDICATING AS THEY HAVE BEEN POOLING MUCH HIGHER
DEWPOINTS AHEAD OF THE FRONT THAN WHAT HAS BEEN ACTUALLY
OCCURRING. THUS...HAVE SIDED WITH THE MORE LOWER DEWPOINT VALUES
WITH THE RAP MODEL WHICH YIELD MLCAPES OF ABOUT 1000 J/KG LATE IN
THE DAY ACRS THE SRN ZONES. AS A RESULT...HAVE PLACED A 20 POP
AHEAD OF THE FRONT ACRS THE NORTH FOR AN ISOLATED SHOWER THROUGH
LATE AFTN. THEREAFTER...HAVE PLACED A 20 POP IN THE SRN ZONES FOR
AN ISOLATED SHOWER/THUNDERSTORM LATE IN THE DAY INTO THE EARLY
EVENING HOURS. FRONTAL PASSAGE WILL BE DELINEATED WITH A WIND
SHIFT TO THE NORTH ALONG WITH SOME GUSTS AS HIGH AS 25 MPH.
TEMPERATURES WILL BE TRICKY GIVEN CLOUDS AND CAA ASSOCIATED WITH
AND JUST BEHIND THE FRONT. HIGHS TODAY SHOULD RANGE FROM NEAR 70
IN THE FAR NW TO THE LOWER 80S IN THE SOUTH.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
THE COLD FRONT AND ANY REMAINING THUNDERSTORMS WILL SHIFT SOUTH OF
OUR AREA THIS EVENING. IN THE WAKE OF THE FRONT...COLD ADVECTION
WILL LIKELY KEEP WINDS UP AROUND 10 MPH FOR MOST OF THE OVERNIGHT
PERIOD. WITH THE COOLER AND DRIER AIRMASS MOVING INTO
PLACE...OVERNIGHT LOWS WILL RUN ABOUT 10 DEGREES COOLER THAN THIS
MORNINGS VALUES. HAVE FORECAST LOW A DEGREE OR TWO ABOVE
GUIDANCE...MAINLY DUE TO WINDS NOT GOING COMPLETELY CALM
OVERNIGHT.
THURSDAY THROUGH FRIDAY...RIDGING WILL DOMINATE OUR WEATHER WITH
ONLY SCATTERED CLOUDS...NO PRECIPITATION...AND GRADUALLY
REBOUNDING TEMPERATURES. MAXIMUM TEMPERATURES WILL BE NEAR CLIMO
ON THURSDAY. THURSDAY NIGHT WILL BE COOL...WITH UPPER 40S TO LOW
50S WITH CLEAR SKIES...CALM WINDS...AND DEWPOINTS IN THE 30S TO
40S.
THE SURFACE RIDGE WILL SHIFT EAST ON FRIDAY...AND MID LEVEL
HEIGHTS AND CORRESPONDING THICKNESSES WILL INCREASE. THIS WILL
LEAD TO HIGH TEMPERATURES ON FRIDAY SEVERAL DEGREES WARMER THAN
THURSDAY...UNDER MOSTLY CLEAR SKIES.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
MODELS ARE IN GENERAL AGREEMENT FOR THE LONG TERM TIME FRAME. DRY
CONDITIONS WILL BE PRESENT TO START OUT THE LONG TERM WITH HIGH
PRESSURE IN PLACE. PREVIOUS MODEL RUNS WERE TRYING TO ALLOW FOR A
FEW THUNDERSTORMS TO DEVELOP DURING THE AFTERNOON SATURDAY AND
SUNDAY. MOST RECENT MODEL RUNS HAVE COME IN DRIER FOR THE WEEKEND
AND BELIEVE THAT WITH THE RIDGE IN PLACE THAT DRY CONDITIONS WILL
PREVAIL. TEMPERATURES WILL GRADUALLY INCREASE THROUGH THE WEEKEND
WITH WARM SOUTHERLY FLOW. TEMPERATURES ON MONDAY WILL BE SIMILAR TO
SUNDAY WITH SOME LOCATIONS A DEGREE OR TWO COOLER THAN SUNDAY DUE TO
AN INCREASE IN CLOUD COVER. MODELS CONTINUE TO SLOW DOWN THE SYSTEM
FOR MONDAY AND TUESDAY AND THEREFORE LIMITED PRECIPITATION CHANCES
ON MONDAY AND MOST OF MONDAY NIGHT TO A SLIGHT CHANCE. EXPECT
TEMPERATURES TO BE A LITTLE COOLER ON TUESDAY WITH INCREASED
PRECIPITATION AND CLOUD COVER ACROSS THE FA.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
A WEAK COLD FRONT WILL SLIP SOUTH OF THE OHIO RIVER BY THIS
EVENING. LIMITED MOISTURE WITH THE FRONT MAY BRING AN ISOLATED
SHOWER OR THUNDERSTORM BEFORE PASSAGE. AFTER PASSAGE...MAINLY
CLEAR SKIES ARE EXPECTED. WINDS WILL VEER TO THE NORTH AND WILL BE
LOCALLY GUSTY WITH FRONTAL PASSAGE. HIGH PRESSURE IS EXPECTED TO
BUILD SOUTH INTO THE GREAT LAKES AND OHIO VALLEY THROUGH THURSDAY.
WINDS WILL VEER TO AN EASTERLY DIRECTION AND WILL RANGE BETWEEN 8
AND 14 KNOTS ON THURSDAY.
OUTLOOK...NO SIGNIFICANT WEATHER EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...LATTO
NEAR TERM...HICKMAN
SHORT TERM...LATTO
LONG TERM...NOVAK
AVIATION...HICKMAN
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
242 PM EDT WED MAY 16 2012
.SYNOPSIS...
A SLOW MOVING UPPER LEVEL AREA OF LOW PRESSURE WILL MOVE EAST ACROSS
THE AREA THROUGH THURSDAY. STRONG HIGH PRESSURE WILL THEN BUILD IN
FROM THE NORTH ON FRIDAY AND REMAIN THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH THURSDAY/...
THE CURRENT WATER VAPOR IMAGERY AND THE LATEST RAP RUN SHOW A WEAK
H5 TROUGH ORIENTED NE TO SW ACROSS THE SRN APPALACHIANS. UPPER
DIVERGENCE ON THE EAST SIDE OF THE TROUGH...WHICH HAS HELPED SPAWN
WIDESPREAD THUNDERSTORM ACTIVITY ALONG THE COAST...IS RESULTING IN
A RAGGED BAROCLINIC LEAF BACK ACROSS THE UPSTATE AND SRN NC
PIEDMONT. THIS HAS CUT DOWN A BIT ON THE INSOLATION ACROSS THE FA
THIS AFTN. EVEN SO...ISOLATED SHRA AND A FEW TSTMS HAVE DEVELOPED
OVER THE REGION...THOUGH COVERAGE HAS BEEN A LITTLE LESS THAN
EXPECTED. THE CONVECTIVE COVERAGE IS EXPECTED TO INCREASE SOME
DURING THE LATE AFTN HOURS...THOUGH NOTHING HIGHER THAN LOW CHANCE
POPS HAS BEEN CARRIED OWING TO THE WEAK SHEAR. WHILE THE STORMS
SHOULD GO INTO THE LATE EVENING HOURS...WE ARE NOT EXPECTING
CONVECTION TO LAST AS LONG AS IT DID LAST NIGHT. THERE IS STILL A
CHANCE THAT ONE OR TWO OF THE STORMS WILL REACH SEVERE
LIMITS...PARTICULARLY ALONG AND SOUTH OF I-85 WHERE THE SHEAR IS A
LITTLE STRONGER...AT LEAST UNTIL AROUND 00 UTC.
THE WEAK TROUGH WILL SETTLE ACROSS THE MIDLANDS LATE TONIGHT AND ON
THURSDAY...PUTTING THE FA UNDER NVA ALOFT. THE TROUGH PASSAGE WILL
BRING A WEAK COLD FRONT THROUGH THE AREA. THE FRONT WILL PUSH IN
FROM THE NE LATE TONIGHT...TURNING THE WINDS OUT OF THE NE AND
BRINGING MORE STABLE AIR ACROSS THE FOOTHILLS AND PIEDMONT. THE
MOUNTAINS WILL SEE LLVL MOISTURE POOLING DURING THE DAY ON THU...AND
A FEW SHRA/TSTMS ARE EXPECTED TO FIRE IN THE AFTN.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
AS OF 230 PM WEDNESDAY...SHORT RANGE MODELS INDICATE THE A BROAD MID
LEVEL TROF WILL PIVOT SE ALLOWING HEIGHTS TO RISE ACROSS THE MTNS
FRIDAY AFTERNOON. NAM FORECAST SOUNDINGS INDICATE A INVERSION AROUND
H6 ALONG WITH VERY MILD MID LEVEL TEMPERATURES...THE GFS ALSO
INDICATES WARM MID LEVEL TEMPERATURES. BOTH SOLUTIONS SUPPORT
AFTERNOON CAPE VALUES BELOW 1000 J/KG WITH SHALLOW LAYER OF CIN. AT
THE SFC...HIGH PRESSURE WILL REMAIN RIDGED NE TO SE ACROSS THE CWA.
GIVEN THE RISING MID HEIGHTS...SFC RIDGING...AND WEAKLY CAPPED
POTENTIAL INSTABILITY I WILL FAVOR DRY CONDITIONS EAST OF THE MTNS.
HOWEVER...CONDITIONS MAY REMAIN LESS CAPPED ACROSS THE MTNS AND
RIDGETOP CONVECTION COULD OCCUR DURING THE LATE AFTERNOON. I WILL
PAINT SCHC POPS ACROSS THE MTN RIDGES. TEMPERATURES SHOULD RANGE
VERY CLOSE TO NORMAL VALUES...MINS NEAR 60 WITH HIGHS NEAR 80.
ON SATURDAY...MID LEVEL HEIGHT VALUES WILL CONTINUE TO SLOWLY RISE
THROUGH THE AFTERNOON. SFC HIGH PRESSURE WILL REMAIN RIDGE SE ACROSS
THE CWA...SUPPLYING A STEADY LLVL NE WIND. THE NE FLOW RESULTS IN
LOWER LLVL DEWPOINTS AND OVERALL DRIER MOISTURE PROFILE. FORECAST
SOUNDINGS INDICATE LITTLE TO NO INSTABILITY ACROSS THE FORECAST
AREA. THE CHCS FOR DEEP CONVECTION APPEARS MINIMAL AND POPS WILL
REMAIN AROUND 10 PERCENT. TEMPERATURES MAY VERIFY WITHIN A DEGREE
ONE TO TWO DEGREES WARMER THAN FRIDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
AS OF NOON WEDNESDAY...A COMPLICATED MID LEVEL PATTERN WILL REMAIN
ACROSS THE SOUTHEAST REGION THROUGH THE EXTENDED PERIOD. IT APPEARS
THAT A BROAD CLOSED LOW WILL REMAIN OVER THE REGION ON SUNDAY...THIS
LOW MAY PHASE WITH AN APPROACHING TROF ON TUESDAY AND WEDNESDAY. THE
TIMING AND PLACEMENT OF THE MAIN FEATURES IS UNCERTAIN. BASED ON
NATIONAL GUIDANCE AND FORECAST CONSISTENCY I WILL ADVERTISE A
GRADUALLY INCREASE IN POPS AND SKY COVER FROM EAST TO WEST SUNDAY
AND MONDAY...THEN KEEP CHCS AND ABUNDANT SKY COVER FOR TUES AND
WEDS. TEMPERATURES SUNDAY THROUGH WEDNESDAY ARE EXPECTED TO RANGE
AROUND NORMAL VALUES.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
AT KCLT...TCU ARE DEVELOPING ACROSS THE REGION...THOUGH THE ONLY
SHRA/TSTMS SO FAR HAVE BEEN ABOUT 20 MI SSE OF THE AIRFIELD. A
SHRA/TSTM COULD DEVELOP JUST ABOUT ANY TIME...BUT I/LL CONFINE A
TEMPO GROUP TO THE 20-22 UTC TIME FRAME AS THIS IS WHEN THE HRRR
BRINGS A LITTLE CONVECTION ACROSS THE AIRFIELD. OTRW WILL CARRY VCSH
TIL 00 UTC. FOG AND LOW CLOUDS COULD DEVELOP TONIGHT...BUT PROBABLY
NOT IF IT DOESN/T RAIN IN THE VCNTY. THEREFORE NOTHING HAS BEEN
CARRIED IN THE TAF.
WIND SPEEDS WILL BE LIGHT TODAY. THEY WILL GRADUALLY VEER TO THE SE
BY LATE AFTN...THEN TURN BACK OUT OF THE NE AFTER MIDNIGHT AS A BACK
DOOR COLD FRONT CROSSES THE REGION.
THE KCLT ASOS OBSERVATION IS PERIODICALLY NOT TRANSMITTING. THE ASOS
IS FINE AND I CAN DIAL INTO IT. ATTM I/M NOT SURE IF IT/S AN FFA OR
NWS COMMS ISSUE BUT WE/LL LOOK INTO IT.
ELSEWHERE...HAVE VCSH AT THE REMAINING SITES THROUGH 00 UTC...WITH
THE EXCEPTION OF KHKY WHERE I/VE GONE WITH VCTS FOR THE NEXT FEW
HOURS. NOT EXPECTING MUCH IN THE WAY OF FOG OR LOW CLOUDS TONIGHT.
HOWEVER...A HEAVY SHOWER AT OR IN THE VCNTY OF AN AIRFIELD WOULD
INCREASE THE CHANCES OF BOTH FOG AND LOW CLOUDS LATER TONIGHT. WINDS
WILL GRADUALLY VEER TO THE SE AT MOST SITES THIS AFTN...THEN TURN
BACK OUT OF THE NE LATE TONIGHT AS A BACK DOOR COLD FRONT CROSSES
THE REGION.
OUTLOOK...EXPECT ISOLD LATE DAY SHOWERS AND TSTMS THRU FRI...ESP
MTNS. THEN DRYING OVER THE WEEKEND. MRNG FOG WILL BE PSBL...ESP MTN
VALLEYS AND NEAR LAKES/RIVERS.
AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...
WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...CSH
NEAR TERM...MCAVOY
SHORT TERM...NED
LONG TERM...NED
AVIATION...MCAVOY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
239 PM EDT WED MAY 16 2012
.SYNOPSIS...
A SLOW MOVING UPPER LEVEL AREA OF LOW PRESSURE WILL MOVE EAST ACROSS
THE AREA THROUGH THURSDAY. STRONG HIGH PRESSURE WILL THEN BUILD IN
FROM THE NORTH ON FRIDAY AND REMAIN THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH THURSDAY/...
THE CURRENT WATER VAPOR IMAGERY AND THE LATEST RAP RUN SHOW A WEAK
H5 THROUGH ORIENTED NE TO SW ACROSS THE SRN APPALACHIANS. UPPER
DIVERGENCE ON THE EAST SIDE OF THE TROUGH...WHICH HAS HELPED SPAWN
WIDESPREAD THUNDERSTORM ACTIVITY ALONG THE COAST...IS RESULTING IN
A RAGGED BAROCLINIC LEAF BACK ACROSS THE UPSTATE AND SRN NC
PIEDMONT. THIS HAS CUT DOWN A BIT ON THE INSOLATION ACROSS THE FA
THIS AFTN. EVEN SO...ISOLATED SHRA AND A FEW TSTMS HAVE DEVELOPED
OVER THE REGION...THOUGH COVERAGE HAS BEEN A LITTLE LESS THAN
EXPECTED. THE CONVECTIVE COVERAGE IS EXPECTED TO INCREASE SOME
DURING THE LATE AFTN HOURS...THOUGH NOTHING HIGHER THAN LOW CHANCE
POPS HAS BEEN CARRIED OWING TO THE WEAK SHEAR. WHILE THE STORMS
SHOULD GO INTO THE LATE EVENING HOURS...WE ARE NOT EXPECTING
CONVECTION TO LAST AS LONG AS IT DID LAST NIGHT. THERE IS STILL A
CHANCE THAT ONE OR TWO OF THE STORMS WILL REACH SEVERE
LIMITS...PARTICULARLY ALONG AND SOUTH OF I-85 WHERE THE SHEAR IS A
LITTLE STRONGER...AT LEAST UNTIL AROUND 00 UTC.
THE WEAK TROUGH WILL SETTLE ACROSS THE MIDLANDS LATE TONIGHT AND ON
THURSDAY...PUTTING THE FA UNDER NVA ALOFT. THE TROUGH PASSAGE WILL
BRING A WEAK COLD FRONT THROUGH THE AREA. THE FRONT WILL PUSH IN
FROM THE NE LATE TONIGHT...TURNING THE WINDS OUT OF THE NE AND
BRINGING MORE STABLE AIR ACROSS THE FOOTHILLS AND PIEDMONT. THE
MOUNTAINS WILL SEE LLVL MOISTURE POOLING DURING THE DAY ON THU...AND
A FEW SHRA/TSTMS ARE EXPECTED TO FIRE IN THE AFTN.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
AS OF 230 PM WEDNESDAY...SHORT RANGE MODELS INDICATE THE A BROAD MID
LEVEL TROF WILL PIVOT SE ALLOWING HEIGHTS TO RISE ACROSS THE MTNS
FRIDAY AFTERNOON. NAM FORECAST SOUNDINGS INDICATE A INVERSION AROUND
H6 ALONG WITH VERY MILD MID LEVEL TEMPERATURES...THE GFS ALSO
INDICATES WARM MID LEVEL TEMPERATURES. BOTH SOLUTIONS SUPPORT
AFTERNOON CAPE VALUES BELOW 1000 J/KG WITH SHALLOW LAYER OF CIN. AT
THE SFC...HIGH PRESSURE WILL REMAIN RIDGED NE TO SE ACROSS THE CWA.
GIVEN THE RISING MID HEIGHTS...SFC RIDGING...AND WEAKLY CAPPED
POTENTIAL INSTABILITY I WILL FAVOR DRY CONDITIONS EAST OF THE MTNS.
HOWEVER...CONDITIONS MAY REMAIN LESS CAPPED ACROSS THE MTNS AND
RIDGETOP CONVECTION COULD OCCUR DURING THE LATE AFTERNOON. I WILL
PAINT SCHC POPS ACROSS THE MTN RIDGES. TEMPERATURES SHOULD RANGE
VERY CLOSE TO NORMAL VALUES...MINS NEAR 60 WITH HIGHS NEAR 80.
ON SATURDAY...MID LEVEL HEIGHT VALUES WILL CONTINUE TO SLOWLY RISE
THROUGH THE AFTERNOON. SFC HIGH PRESSURE WILL REMAIN RIDGE SE ACROSS
THE CWA...SUPPLYING A STEADY LLVL NE WIND. THE NE FLOW RESULTS IN
LOWER LLVL DEWPOINTS AND OVERALL DRIER MOISTURE PROFILE. FORECAST
SOUNDINGS INDICATE LITTLE TO NO INSTABILITY ACROSS THE FORECAST
AREA. THE CHCS FOR DEEP CONVECTION APPEARS MINIMAL AND POPS WILL
REMAIN AROUND 10 PERCENT. TEMPERATURES MAY VERIFY WITHIN A DEGREE
ONE TO TWO DEGREES WARMER THAN FRIDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
AS OF NOON WEDNESDAY...A COMPLICATED MID LEVEL PATTERN WILL REMAIN
ACROSS THE SOUTHEAST REGION THROUGH THE EXTENDED PERIOD. IT APPEARS
THAT A BROAD CLOSED LOW WILL REMAIN OVER THE REGION ON SUNDAY...THIS
LOW MAY PHASE WITH AN APPROACHING TROF ON TUESDAY AND WEDNESDAY. THE
TIMING AND PLACEMENT OF THE MAIN FEATURES IS UNCERTAIN. BASED ON
NATIONAL GUIDANCE AND FORECAST CONSISTENCY I WILL ADVERTISE A
GRADUALLY INCREASE IN POPS AND SKY COVER FROM EAST TO WEST SUNDAY
AND MONDAY...THEN KEEP CHCS AND ABUNDANT SKY COVER FOR TUES AND
WEDS. TEMPERATURES SUNDAY THROUGH WEDNESDAY ARE EXPECTED TO RANGE
AROUND NORMAL VALUES.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
AT KCLT...TCU ARE DEVELOPING ACROSS THE REGION...THOUGH THE ONLY
SHRA/TSTMS SO FAR HAVE BEEN ABOUT 20 MI SSE OF THE AIRFIELD. A
SHRA/TSTM COULD DEVELOP JUST ABOUT ANY TIME...BUT I/LL CONFINE A
TEMPO GROUP TO THE 20-22 UTC TIME FRAME AS THIS IS WHEN THE HRRR
BRINGS A LITTLE CONVECTION ACROSS THE AIRFIELD. OTRW WILL CARRY VCSH
TIL 00 UTC. FOG AND LOW CLOUDS COULD DEVELOP TONIGHT...BUT PROBABLY
NOT IF IT DOESN/T RAIN IN THE VCNTY. THEREFORE NOTHING HAS BEEN
CARRIED IN THE TAF.
WIND SPEEDS WILL BE LIGHT TODAY. THEY WILL GRADUALLY VEER TO THE SE
BY LATE AFTN...THEN TURN BACK OUT OF THE NE AFTER MIDNIGHT AS A BACK
DOOR COLD FRONT CROSSES THE REGION.
THE KCLT ASOS OBSERVATION IS PERIODICALLY NOT TRANSMITTING. THE ASOS
IS FINE AND I CAN DIAL INTO IT. ATTM I/M NOT SURE IF IT/S AN FFA OR
NWS COMMS ISSUE BUT WE/LL LOOK INTO IT.
ELSEWHERE...HAVE VCSH AT THE REMAINING SITES THROUGH 00 UTC...WITH
THE EXCEPTION OF KHKY WHERE I/VE GONE WITH VCTS FOR THE NEXT FEW
HOURS. NOT EXPECTING MUCH IN THE WAY OF FOG OR LOW CLOUDS TONIGHT.
HOWEVER...A HEAVY SHOWER AT OR IN THE VCNTY OF AN AIRFIELD WOULD
INCREASE THE CHANCES OF BOTH FOG AND LOW CLOUDS LATER TONIGHT. WINDS
WILL GRADUALLY VEER TO THE SE AT MOST SITES THIS AFTN...THEN TURN
BACK OUT OF THE NE LATE TONIGHT AS A BACK DOOR COLD FRONT CROSSES
THE REGION.
OUTLOOK...EXPECT ISOLD LATE DAY SHOWERS AND TSTMS THRU FRI...ESP
MTNS. THEN DRYING OVER THE WEEKEND. MRNG FOG WILL BE PSBL...ESP MTN
VALLEYS AND NEAR LAKES/RIVERS.
AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...
WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...CSH
NEAR TERM...MCAVOY
SHORT TERM...NED
LONG TERM...NED
AVIATION...MCAVOY
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1228 PM CDT WED MAY 16 2012
.UPDATE...
SEE UPDATED AVIATION DISCUSSION BELOW.
THE VAST MAJORITY OF THE TODAY PERIOD FORECAST IS IN FINE SHAPE.
DID BEEF UP WIND SPEEDS A FEW MORE KNOTS ACROSS THE MISSOURI RIVER
VALLEY AND ISSUE A WIND ADVISORY VALID UNTIL 7 PM CDT FOR THAT
PORTION OF THE CWA...PER BUFKIT MOMENTUM TRANSFER TOOL AND 06Z/12Z
0.5KM FORECAST WIND SPEEDS /30 TO 35 KNOTS/ TODAY. THAT AND A FEW
OBSERVATIONS WEST AND NORTHWEST OF THE CWA HAD ALREADY CHIMED IN
WITH MARGINAL TO LOW END ADVISORY CRITERIA AT 9 AM CDT AND 10 AM
CDT THIS MORNING.
ALSO...BASED OFF THE LATEST AVAILABLE GFS/NAM AND RAP LOW LEVEL
THERMAL PROGS...DID BUMP UP TEMPERATURES FROM BROWN AND SPINK
COUNTIES WESTWARD APPX 2 TO 5 DEGREES. UPDATES ARE OUT.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TODAY THROUGH FRIDAY
WINDS TODAY...AND PCPN CHANCES TONIGHT ARE THE MAIN FORECAST CHALLENGES.
AN AREA OF HIGH PRESSURE OVER THE EASTERN DAKOTAS THIS MORNING
WILL BE REPLACED BY A LOW PRESSURE SYSTEM CURRENTLY OVER THE
NORTHERN HIGH PLAINS. WITH A STRENGTHENING PRESSURE GRADIENT
ACROSS THE WESTERN DAKOTAS TODAY WINDS MAY APPROACH ADVISORY
CRITERIA. GFS LAMP GUIDANCE IS SUGGESTING SUSTAINED WINDS ALONG
THE MISSOURI RIVER COULD REACH 27 KNOTS WITH WIND GUSTS AROUND 35
KNOTS...OR SUB ADVISORY. WILL GO HEADLINE FREE FOR NOW AND LET THE
DAY SHIFT ISSUE AN ADVISORY AS NEEDED.
LATER TONIGHT...A 50 TO 60 KNOT SW ORIENTATE LLJ DEVELOPS OVER
EASTERN SD AND WESTERN MN. DECENT UVM AND MOISTURE ADVECTION ALONG
THE NOSE OF THE LLJ MAY RESULT IN SCT SHOWERS AND THUNDERSTORMS
FOR THE NE CWA AFTER 6Z. WITH GOOD MODEL TO MODEL CONTINUITY WITH
THIS FEATURE...HAVE DECIDED TO INCREASE POPS SOME.
ANOTHER LLJ WILL DEVELOPS THURSDAY NIGHT ACROSS NORTHERN MN WITH
THIS CWA LIKELY SEEING DRY CONDITIONS. THUS HAVE REMOVED THE
PREVIOUS FORECAST POPS.
.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY
THE MODELS ALL SHOW A COLD FRONT MAKING ITS WAY ACROSS THE CWA
LATE FRIDAY NIGHT THROUGH SATURDAY EVENING. THEY ALL HAVE SOME
DIFFERENCES IN THE SPEED OF THE FRONT ALONG WITH THE QPF OCCURRING
IN ASSOCIATION WITH IT. THEY WERE DIFFERENT MAINLY AS A RESULT OF
THE STRENGTH AND TIMING OF THE SURFACE LOW PRESSURE AREA LIFTING
NORTHEAST ALONG THE FRONT. NONETHELESS...IT DOES LOOK LIKE A
STRONG BOUNDARY WITH PLENTY OF INSTABILITY ALONG AND BEHIND IT.
ALREADY HAD IN DECENT CHANCE POPS IN THE GRIDS WITH THE FRONT FOR
FRIDAY NIGHT THROUGH SATURDAY NIGHT. COOLER AND DRIER HIGH
PRESSURE AIR WILL PUSH IN FOR SUNDAY WITH HIGHS AROUND 70 FOR THE
AFTERNOON. THE SURFACE HIGH PRESSURE AREA WILL PUSH EAST MONDAY
AND TUESDAY WITH WARMER AIR RETURNING ON THE BACKSIDE. SOUTH WINDS
WILL ALSO PICK UP INTO MONDAY BRINGING IN THE WARMER AIR. MONDAY
WILL BE IN THE 70S ACROSS THE CWA WITH MAINLY 80S ON TUESDAY. IT
DOES LOOK LIKE MONDAY AND TUESDAY WILL BE DRY.
&&
.AVIATION...
18Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
VFR CONDITIONS WILL PREVAIL THROUGH TODAY AND TONIGHT AT ALL
TERMINALS. SOUTH TO SOUTHEAST WINDS WILL INCREASE FROM WEST TO
EAST THROUGH THE AFTERNOON. WINDS WILL BE STRONGEST OVER THE KMBG AND KPIR
TERMINALS WHERE SPEEDS WILL RANGE FROM 25 TO 35 KNOTS BY 21Z. THE
WINDS WILL FALL OFF EARLY THIS EVENING INTO THE 15 TO 20 KNOT
RANGE AT ALL TERMINALS.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY UNTIL 7 PM CDT /6 PM MDT/ THIS EVENING FOR BUFFALO-
CAMPBELL-CORSON-DEWEY-HUGHES-HYDE-JONES-LYMAN-POTTER-
STANLEY-SULLY-WALWORTH.
MN...NONE.
&&
$$
UPDATE...WISE
SHORT TERM...DORN
LONG TERM...MOHR
AVIATION...WISE
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1127 AM CDT WED MAY 16 2012
.UPDATE...
THE VAST MAJORITY OF THE TODAY PERIOD FORECAST IS IN FINE SHAPE.
DID BEEF UP WIND SPEEDS A FEW MORE KNOTS ACROSS THE MISSOURI RIVER
VALLEY AND ISSUE A WIND ADVISORY VALID UNTIL 7 PM CDT FOR THAT
PORTION OF THE CWA...PER BUFKIT MOMENTUM TRANSFER TOOL AND 06Z/12Z
0.5KM FORECAST WIND SPEEDS /30 TO 35 KNOTS/ TODAY. THAT AND A FEW
OBSERVATIONS WEST AND NORTHWEST OF THE CWA HAD ALREADY CHIMED IN
WITH MARGINAL TO LOW END ADVISORY CRITERIA AT 9 AM CDT AND 10 AM
CDT THIS MORNING.
ALSO...BASED OFF THE LATEST AVAILABLE GFS/NAM AND RAP LOW LEVEL
THERMAL PROGS...DID BUMP UP TEMPERATURES FROM BROWN AND SPINK
COUNTIES WESTWARD APPX 2 TO 5 DEGREES. UPDATES ARE OUT.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TODAY THROUGH FRIDAY
WINDS TODAY...AND PCPN CHANCES TONIGHT ARE THE MAIN FORECAST CHALLENGES.
AN AREA OF HIGH PRESSURE OVER THE EASTERN DAKOTAS THIS MORNING
WILL BE REPLACED BY A LOW PRESSURE SYSTEM CURRENTLY OVER THE
NORTHERN HIGH PLAINS. WITH A STRENGTHENING PRESSURE GRADIENT
ACROSS THE WESTERN DAKOTAS TODAY WINDS MAY APPROACH ADVISORY
CRITERIA. GFS LAMP GUIDANCE IS SUGGESTING SUSTAINED WINDS ALONG
THE MISSOURI RIVER COULD REACH 27 KNOTS WITH WIND GUSTS AROUND 35
KNOTS...OR SUB ADVISORY. WILL GO HEADLINE FREE FOR NOW AND LET THE
DAY SHIFT ISSUE AN ADVISORY AS NEEDED.
LATER TONIGHT...A 50 TO 60 KNOT SW ORIENTATE LLJ DEVELOPS OVER
EASTERN SD AND WESTERN MN. DECENT UVM AND MOISTURE ADVECTION ALONG
THE NOSE OF THE LLJ MAY RESULT IN SCT SHOWERS AND THUNDERSTORMS
FOR THE NE CWA AFTER 6Z. WITH GOOD MODEL TO MODEL CONTINUITY WITH
THIS FEATURE...HAVE DECIDED TO INCREASE POPS SOME.
ANOTHER LLJ WILL DEVELOPS THURSDAY NIGHT ACROSS NORTHERN MN WITH
THIS CWA LIKELY SEEING DRY CONDITIONS. THUS HAVE REMOVED THE
PREVIOUS FORECAST POPS.
.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY
THE MODELS ALL SHOW A COLD FRONT MAKING ITS WAY ACROSS THE CWA
LATE FRIDAY NIGHT THROUGH SATURDAY EVENING. THEY ALL HAVE SOME
DIFFERENCES IN THE SPEED OF THE FRONT ALONG WITH THE QPF OCCURRING
IN ASSOCIATION WITH IT. THEY WERE DIFFERENT MAINLY AS A RESULT OF
THE STRENGTH AND TIMING OF THE SURFACE LOW PRESSURE AREA LIFTING
NORTHEAST ALONG THE FRONT. NONETHELESS...IT DOES LOOK LIKE A
STRONG BOUNDARY WITH PLENTY OF INSTABILITY ALONG AND BEHIND IT.
ALREADY HAD IN DECENT CHANCE POPS IN THE GRIDS WITH THE FRONT FOR
FRIDAY NIGHT THROUGH SATURDAY NIGHT. COOLER AND DRIER HIGH
PRESSURE AIR WILL PUSH IN FOR SUNDAY WITH HIGHS AROUND 70 FOR THE
AFTERNOON. THE SURFACE HIGH PRESSURE AREA WILL PUSH EAST MONDAY
AND TUESDAY WITH WARMER AIR RETURNING ON THE BACKSIDE. SOUTH WINDS
WILL ALSO PICK UP INTO MONDAY BRINGING IN THE WARMER AIR. MONDAY
WILL BE IN THE 70S ACROSS THE CWA WITH MAINLY 80S ON TUESDAY. IT
DOES LOOK LIKE MONDAY AND TUESDAY WILL BE DRY.
&&
.AVIATION...
12Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
VFR CONDITIONS WILL PREVAIL THROUGH TODAY AND TONIGHT AT ALL
TERMINALS. SOUTH TO SOUTHEAST WINDS WILL BECOME QUITE GUSTY BY MID
TO LATE MORNING AND WILL INCREASE THROUGH THE DAY. WINDS WILL BE
STRONGEST OVER THE KMBG AND KPIR TERMINALS WHERE SPEEDS WILL RANGE
FROM 25 TO 35 KNOTS BY AFTERNOON. THE WINDS WILL FALL OFF EARLY
THIS EVENING INTO THE 15 TO 20 KNOT RANGE AT ALL TERMINALS.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY UNTIL 7 PM CDT /6 PM MDT/ THIS EVENING FOR BUFFALO-
CAMPBELL-CORSON-DEWEY-HUGHES-HYDE-JONES-LYMAN-POTTER-
STANLEY-SULLY-WALWORTH.
MN...NONE.
&&
$$
UPDATE...DORN
SHORT TERM...SD
LONG TERM...MOHR
AVIATION...MOHR
WEATHER.GOV/ABERDEEN