Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/16/13
AREA FORECAST DISCUSSION...UPDATE FOR AVIATION
NWS LITTLE ROCK AR
1235 AM CDT FRI JUN 14 2013
.AVIATION...
OVERALL VFR FLIGHT CONDITIONS ARE EXPECTED OVER THE NEXT 24 HOURS. A
COLD FRONT WILL SLOWLY SAG SW OVERNIGHT AND BRING A BIT MORE DRIER
AIR TO AR. THIS SHOULD LIMIT ANY FOG FORMATION AROUND SUNRISE
FRIDAY. WINDS AHEAD OF THE FRONT WILL BE LIGHT FROM THE
SOUTH...WHILE BEHIND THE FRONT FROM THE NE AT 3 TO 8 KNOTS. (59)
&&
.PREV DISCUSSION... /ISSUED 817 PM CDT THU JUN 13 2013/
.UPDATE...
COLD FRONT CONTINUES TO WORK ITS WAY ACROSS THE STATE THIS EVENING
WITH THE BOUNDARY EASY TO SPOT ON WSR-88D IMAGERY. A FEW SHOWERS
HAVE DEVELOPED OVER SOUTHEAST ARKANSAS ALONG THE BOUNDARY BUT WITH
LOSS OF HEATING...NOT EXPECTING THESE TO REMAIN TOGETHER MUCH
LONGER. CURRENT PRECIPITATION GRIDS...AND ALL GRIDS FOR THAT
MATTER...REMAIN IN GOOD SHAPE AND NO CHANGES ARE NEEDED TONIGHT.
TEMPERATURES ACROSS THE BOUNDARY ARE SLIGHTLY COOLER BUT DEW POINT
TEMPERATURES ARE MUCH LOWER. DEW POINT AT THE WFO HAVE DROPPED 8
DEGREES IN THE PAST HOUR AFTER FROPA WITH THE DRIER AIR MOVING
SOUTH BEHIND THE BOUNDARY.
&&
PREV DISCUSSION... /ISSUED 245 PM CDT THU JUN 13 2013/
SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT
W-E ORIENTED CDFNT WAS SITUATED ACRS CNTRL AR AT MID AFTN. DEWPOINTS
IN THE LOWER AND MID 70S HAVE POOLED IN THE VCNTY OF THE BNDRY...
RESULTING IN HEAT INDICES BETWEEN 100 AND 105 DEGREES. HAVE SEEN A
FEW WEAK RADAR RETURNS OVR ERN AR. THE RUC AND HRRR MODELS CONT TO
INDCD ISOLD SHRA/TSRA DVLPG ALONG THE FNT OVR CNTRL/SERN AR LATE
THIS AFTN/EARLY EVENING. THUS...WL LEAVE SOME SMALL POPS IN PER
GOING FCST.
THE AFOREMENTIONED CDFNT WL EVENTUALLY STALL OUT TO THE SW OF THE
AREA BY FRI AS A WEAK SFC RDG BLDS INTO AR. THE BNDRY WL MEANDER IN
THE VCNTY OF WRN AR HEADING INTO THE WEEKEND. CANNOT RULE OF A STRAY
SHRA/TSRA FRI AND SAT ALONG WITH WRN PERIPHERY OF THE SFC RDG...BUT
WL KEEP A DRY FCST IN PLACE. E/NELY SFC WINDS BEHIND THE FNT WL
BRING DRIER AND SLIGHTLY COOLER AIRMASS TO MUCH OF THE FA.
THE SFC HIGH WL WEAKEN ENOUGH BY SUN/SUN NGT FOR A RETURN OF SLY
WINDS...ALONG WITH INCRSG LOW LVL RH. MEANWHILE...THE UPR LVL FLOW
WL FLATTEN TO ALLOW A NEW CDFNT WL APCH AR FM THE N...ALONG WITH A
BETTER CHC OF SHRA/TSRA. THE UNSETTLED PATTERN WL CONT INTO THE LONG
TERM PD.
LONG TERM...MONDAY THROUGH THURSDAY
UPPER RIDGE WILL BE PUSHED SOUTH OF THE STATE FOR THE BEGINNING OF
NEXT WEEK...AND ALLOW A COLD FRONT TO MOVE INTO THE STATE. MODELS
ARE IN BETTER AGREEMENT OF MOVING THIS FRONT FURTHER INTO THE STATE
THAN PREVIOUS RUNS...AND HAVE INCREASED POPS TO THE CHANCE CATEGORY
FOR MONDAY INTO TUESDAY. UPPER RIDGE WILL BEGIN TO BUILD BACK OVER
THE AREA WEDNESDAY INTO THURSDAY...WITH RAIN CHANCES DWINDLING.
TEMPERATURES WILL CONTINUE TO BE ABOVE NORMAL ACROSS THE SOUTH...
WHILE NORTHERN ARKANSAS WILL HAVE A LITTLE COOLER TEMPERATURES DUE
TO CLOUD COVER AND RAINFALL.
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS FLAGSTAFF AZ
245 PM MST FRI JUN 14 2013
.SYNOPSIS...THERE IS A SLIGHT CHANCE OF THUNDERSTORMS ON SATURDAY
MOSTLY OVER THE HIGHER TERRAIN OF NORTHERN ARIZONA...BUT LITTLE
RAINFALL IS EXPECTED. BREEZY CONDITIONS WILL PERSIST WITH
TEMPERATURES AROUND NORMAL. BY SUNDAY AND INTO NEXT
WEEK...INCREASING SOUTHWEST WINDS AND MUCH DRIER AIR WILL END
THE CHANCE OF ANY THUNDERSTORMS...WITH SEASONABLY WARM TEMPERATURES.
&&
.DISCUSSION...ONLY A FEW ISOLATED SHOWERS OVER THE EASTERN RIM AND
WHITE MTS SO FAR THIS AFTERNOON...LESS THAN YESTERDAY...AND IN
AGREEMENT WITH THE HRRR MODEL RUNS. EXPECT ANY SHOWERS TO DIMINISH
EARLY THIS EVENING BRINGING MOSTLY CLEAR SKIES FOR THE REST OF THE
NIGHT.
MINOR DIGGING OF THE TROUGH OFF THE WEST COAST WILL ALLOW FOR A
MORE SOUTHERLY FETCH ACROSS ARIZONA ON SATURDAY...BRINGING A
TEMPORARY INCREASE IN MOISTURE...AND RESULTING IN ISOLATED TO
SCATTERED WEAK THUNDERSTORM ACTIVITY. MODEL RUNS INDICATE THE
GREATEST CHANCES FOR THUNDERSTORMS WILL BE ALONG AND NORTH OF THE
MOGOLLON RIM SATURDAY AFTERNOON..WHERE THE MOISTURE AXIS COINCIDES
WITH THE TIME OF MAXIMUM HEATING...AND NORTHEASTERLY STORM MOTION.
LITTLE PRECIPITATION IS EXPECTED FROM THE STORMS AS THE LOWER
ATMOSPHERE WILL REMAIN QUITE DRY.
MUCH DRIER AIR ADVECTS INTO THE AREA LATE SUNDAY THROUGH EARLY NEXT
WEEK AS THE FLOW TURNS MORE WESTERLY. NO PRECIPITATION IS EXPECTED
THROUGH NEXT WEEK AS A STRENGTHENING TROUGH DEVELOPS OVER THE
PACIFIC NORTHWEST...KEEPING A VERY DRY SOUTHWESTERLY FLOW IN PLACE
OVER ARIZONA. BREEZY...TO OCCASIONALLY WINDY CONDITIONS CAN BE
EXPECTED BY MIDWEEK...POSSIBLY APPROACHING CRITICAL FIRE WEATHER
THRESHOLDS.
&&
.AVIATION...
FOR THE 00Z PACKAGE...VFR CONDITIONS EXPECTED FOR THE NEXT 24 HOURS.
SOUTHWEST WINDS 10-20 WITH GUSTS TO 25 KTS WILL PERSIST THROUGH
03Z/SAT. ISOLATED HIGH BASED -SHRA/-TSRA MAY EXIST EAST OF A
KFLG-K0V7 LINE WITH GUSTY WINDS ACCOMPANYING ANY THUNDERSTORM
ACTIVITY...TAPERING OFF BY 03Z/SAT. SIMILAR CONDITIONS XPCTED
SATURDAY WITH -SHRA/-TSRA POSSIBLE AFTER 18Z EAST OF A KPRC-KGCN
LINE WITH GUSTY WINDS AND LITTLE RAIN. AVIATION DISCUSSION NOT
UPDATED FOR AMENDMENTS.
&&
.FIRE WEATHER...A MODEST INCREASE IN MOISTURE WILL CONTINUE TO IMPACT
NORTHERN ARIZONA THROUGH SATURDAY. VERY DRY CONDITIONS AND LOW RH
VALUES WILL PERSIST ACROSS FAR WESTERN ZONES...PRIMARILY WEST OF A
KPRC-KFLG LINE WITH DEWPOINTS AND RH INCREASING WITH EASTWARD
EXTENT. PRIMARILY DRY THUNDERSTORM ACTIVITY WHICH HAS BEEN LIMITED
TO THE WHITE MOUNTAIN REGION THE PAST COUPLE DAYS WILL EXPAND
SATURDAY TO ENCOMPASS THE EASTERN TWO THIRDS OF NORTHERN AZ. THESE
THUNDERSTORMS WILL PRODUCE GUSTY WINDS...BUT LITTLE RAIN. THE WHITE
MOUNTAIN AREA MAY FARE BETTER WITH WETTING RAINFALL ACCOMPANYING THE
HEAVIEST DOWNPOURS. DRY AIR ATTEMPTS TO RETURN SUNDAY WITH TSTORM
ACTIVITY BECOMING LIMITED TO THE WHITE MOUNTAINS AND LOWER RH VALUES
PUSHING IN FROM THE WEST.
MONDAY THROUGH WEDNESDAY...
EXPECT BREEZY SOUTHWEST WINDS EACH AFTERNOON WITH SPEEDS BELOW
CRITICAL VALUES. AFTERNOON RELATIVE HUMIDITIES SHOULD BE FROM 10 TO
15 PERCENT ALONG THE MOGOLLON RIM AND SINGLE DIGITS ELSEWHERE.
WEDNESDAY MAY SEE AN INCREASE IN AFTERNOON BREEZINESS AND ENHANCED
FIRE WEATHER POTENTIAL BUT STILL EXPECTED TO REMAIN BELOW CRITICAL
THRESHOLDS FOR NOW. DESPITE THE FORECAST REMAINING BELOW CRITICAL
RED FLAG CONDITIONS...IT MAY APPROACH IT AND FIRE DANGER WILL
REMAIN VERY HIGH WITH HIGH HAINES VALUES EACH AFTERNOON.
&&
.FGZ WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC.........BAK
AVIATION.......OUTLER
FIRE WEATHER...OUTLER
FOR NORTHERN ARIZONA WEATHER INFORMATION VISIT
WEATHER.GOV/FLAGSTAFF
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1224 PM MDT FRI JUN 14 2013
.UPDATE...
ISSUED AT 1220 PM MDT FRI JUN 14 2013
INCREASED POPS ACROSS THE SOUTHERN I-25 CORRIDOR AND PARTS OF THE
EASTERN PLAINS TO CLOSER REFLECT CURRENT RADAR TRENDS AND LATEST
HRRR AND RAP RUNS. -PJC
UPDATE ISSUED AT 916 AM MDT FRI JUN 14 2013
UPDATED THE GRIDS TO INCREASE CLOUD COVER ACROSS THE AREA OVER THE
NEXT FEW HOURS. -PJC
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 343 AM MDT FRI JUN 14 2013
SOUTHWEST FLOW ALOFT CONTINUES OVER THE AREA TODAY AND TONIGHT...AS
STRONG UPPER TROUGH LIFTS NORTHEAST FROM THE NORTHERN ROCKIES INTO
THE CANADIAN PRAIRIE. RATHER DIFFUSE SURFACE FRONT OVER THE EASTERN
PLAINS HAS BEEN GRADUALLY DRIFTING BACK EASTWARD THIS MORNING...WITH
WARMER/DRIER AIR MASS SPREADING EAST FROM THE MOUNTAINS ACROSS THE
I-25 CORRIDOR. OVERALL...WINDS TODAY LOOK LESS THAN THE PAST FEW
DAYS AS MID LEVEL FLOW DECREASES AND SURFACE GRADIENT RELAXES. FAR
SOUTHEAST PLAINS...MAINLY BACA COUNTY...COULD GET FAIRLY WINDY AHEAD
OF LEE SURFACE TROUGH...THOUGH RH REMAINS JUST ABOVE 15 PERCENT AND
WILL REFRAIN FROM ISSUING A FIRE WX HIGHLIGHT. WITH THIN PLUME OF
MID LEVEL MOISTURE OVER THE AREA ONCE AGAIN...EXPECT ANOTHER ROUND
OF MAINLY ISOLATED AFTERNOON AND EVENING THUNDERSTORMS...WITH BEST
CHANCES ALONG AND EAST OF A TRINIDAD TO LA JUNTA TO EADS
LINE...WHERE DEWPOINTS HOLD IN THE 40S AND CAPES PUSH ABOVE 1000
J/KG. SOME CONCERN ABOUT LOW RH AND BRIEFLY GUSTY WINDS OVER
TELLER/EL PASO COUNTIES THIS AFTERNOON...AS SUCCESSIVE RUNS OF THE
HRRR/NAM HAVE TRENDED DRIER AND WINDIER THE PAST FEW HOURS. IN
FACT...LATEST HRRR DROPS DEWPOINTS INTO THE TEENS OVER NORTHERN EL
PASO COUNTY BY EARLY AFTERNOON...WHICH SUGGESTS FAIRLY DEEP
MIXING...THOUGH MODEL SURFACE/BL WINDS NEVER GET MUCH ABOVE 15
KNOTS. MAX TEMPS CONTINUE ON THE HOT SIDE...VERY SIMILAR TO
YESTERDAY. OVERNIGHT...CONVECTION LINGERS IN THE DEEPER MOISTURE
OVER THE FAR EASTERN PLAINS PAST SUNSET...THOUGH MOST AREAS SHOULD
SEE TSRA END BY MIDNIGHT AS POTENTIAL MCS LIFTS NORTHEAST INTO NEB.
SURFACE FRONT SHOULD GET A SOUTHWESTWARD SHOVE BY DEPARTING
CONVECTION...WITH LOW LEVEL MOISTURE SLOSHING BACK TO THE I-25
CORRIDOR AND EASTERN MOUNTAINS BY EARLY SATURDAY MORNING.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 343 AM MDT FRI JUN 14 2013
SOME CHANGES TO THE EXTENDED FOR THE WEEKEND INTO EARLY NEXT WEEK.
MODEL SOLUTIONS HAVE AN UPPER LEVEL RIDGE ACROSS THE ROCKIES
SATURDAY THROUGH TUESDAY...WITH SEVERAL DISTURBANCES MOVING ACROSS THE
REGION UNDER THE RIDGE. THE MAIN MODEL DIFFERENCES ARE IN THE
AMOUNT AND TYPE OF CONVECTION THAT MAY BE POSSIBLE ACROSS THE
PLAINS. MOISTURE WILL BE THE BIGGEST COMPLICATION AND WILL
DETERMINE HOW MUCH PRECIPITATION FALLS WITH THUNDERSTORM ACTIVITY.
MOISTURE STILL LOOKS MODEST ON SATURDAY AND MODEL SOLUTIONS ARE
HINTING THAT THUNDERSTORM ACTIVITY MAY BE LIMITED. MODELS DEVELOP
THUNDERSTORMS OVER THE MOUNTAINS BY SATURDAY AFTERNOON...WITH SOME
MOVEMENT OVER THE PALMER DIVIDE AND RATON MESA THROUGH THE
EVENING. LIGHTNING AND STRONG WIND GUSTS...POSSIBLY AS HIGH WAS 50
MPH...WILL BE THE MAIN THREATS...WITH VERY LITTLE PRECIPITATION
ACTUALLY FALLING.
MODELS A BIT MORE IMPRESSIVE WITH PRECIPITATION CHANCES SUNDAY
THROUGH TUESDAY. MOISTURE WILL ADVECT NORTHWARD OUT OF THE DESERT
SOUTHWEST WHICH SHOULD LEAD TO MORE WIDESPREAD SHOWER AND
THUNDERSTORM ACTIVITY. EXPECT THUNDERSTORMS TO DEVELOP BY LATE
MORNING EACH DAY OVER THE MOUNTAINS...AND SPREAD EAST INTO THE
I-25 CORRIDOR BY THE AFTERNOON. THE GFS IS MOST IMPRESSIVE
DEVELOPING MCS EVENTS THAT PUSH EAST ACROSS THE PLAINS THROUGH THE
OVERNIGHT PERIODS. THIS WOULD BRING LOCALLY HEAVY RAINFALL UNDER
THE STORM SYSTEMS. FOR NOW HAVE WIDESPREAD LOW POPS ACROSS THE
REGION AND HOPEFULLY THE REGION SEES SOME BENEFICIAL RAINFALL.
AN UPPER LEVEL LOW WILL MOVE INTO THE PACIFIC NORTHWEST BY
WEDNESDAY WHICH WILL SPREAD STRONG DRY SOUTHWEST FLOW ACROSS THE
ROCKIES. THIS WILL LEAD TO DRY AND HOT CONDITIONS ACROSS COLORADO
ALONG WITH INCREASED RISK OF DANGEROUS FIRE WEATHER CONDITIONS.
AREAS OVER THE CONTINENTAL DIVIDE...SAN LUIS VALLEY AND EASTERN
MOUNTAINS WILL LIKELY SEE THE DANGEROUS CONDITIONS BY WEDNESDAY
AFTERNOON WHICH WILL SPREAD EAST ACROSS THE PLAINS FOR THURSDAY
AND FRIDAY. WE WILL CONTINUE TO MONITOR THE SITUATION FOR MID TO
LATE NEXT WEEK IN REGARDS TO FIRE WEATHER. MOZLEY
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1103 AM MDT FRI JUN 14 2013
KALS...ISOLATED HIGH BASED STORMS WILL DEVELOP OVER THE
SURROUNDING MOUNTAINS DURING THE AFTERNOON AND EARLY EVENING.
THREAT OF ANY CONVECTION NEAR KALS IS LOW AND DID NOT PUT ANY IN
TAFS. HOWEVER...OUTFLOWS FROM THE STORMS COULD AFFECT KALS.
KCOS AND KPUB...CLOUDS WILL GRADUALLY DISSIPATE...AND ANTICIPATE
CONVECTION IN THE VICINITY OF BOTH SITES DURING THE AFTERNOON AND
EARLY EVENING. NEARBY CONVECTION COULD PRODUCE GUSTY OUTFLOWS WHICH
MAY IMPACT TAF SITES. CURRENT TAFS HAVE A COLD FRONT PASSING
AROUND SUNRISE SATURDAY. HOWEVER...OUTFLOW FROM FRIDAY EVENING
CONVECTION COULD RESULT IN AN EARLIER FRONTAL PASSAGE. --PGW--
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...PJC
SHORT TERM...PETERSEN
LONG TERM...MOZLEY
AVIATION...PGW
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1115 AM MDT FRI JUN 14 2013
.UPDATE...
ISSUED AT 916 AM MDT FRI JUN 14 2013
UPDATED THE GRIDS TO INCREASE CLOUD COVER ACROSS THE AREA OVER THE
NEXT FEW HOURS. -PJC
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 343 AM MDT FRI JUN 14 2013
SOUTHWEST FLOW ALOFT CONTINUES OVER THE AREA TODAY AND TONIGHT...AS
STRONG UPPER TROUGH LIFTS NORTHEAST FROM THE NORTHERN ROCKIES INTO
THE CANADIAN PRAIRIE. RATHER DIFFUSE SURFACE FRONT OVER THE EASTERN
PLAINS HAS BEEN GRADUALLY DRIFTING BACK EASTWARD THIS MORNING...WITH
WARMER/DRIER AIR MASS SPREADING EAST FROM THE MOUNTAINS ACROSS THE
I-25 CORRIDOR. OVERALL...WINDS TODAY LOOK LESS THAN THE PAST FEW
DAYS AS MID LEVEL FLOW DECREASES AND SURFACE GRADIENT RELAXES. FAR
SOUTHEAST PLAINS...MAINLY BACA COUNTY...COULD GET FAIRLY WINDY AHEAD
OF LEE SURFACE TROUGH...THOUGH RH REMAINS JUST ABOVE 15 PERCENT AND
WILL REFRAIN FROM ISSUING A FIRE WX HIGHLIGHT. WITH THIN PLUME OF
MID LEVEL MOISTURE OVER THE AREA ONCE AGAIN...EXPECT ANOTHER ROUND
OF MAINLY ISOLATED AFTERNOON AND EVENING THUNDERSTORMS...WITH BEST
CHANCES ALONG AND EAST OF A TRINIDAD TO LA JUNTA TO EADS
LINE...WHERE DEWPOINTS HOLD IN THE 40S AND CAPES PUSH ABOVE 1000
J/KG. SOME CONCERN ABOUT LOW RH AND BRIEFLY GUSTY WINDS OVER
TELLER/EL PASO COUNTIES THIS AFTERNOON...AS SUCCESSIVE RUNS OF THE
HRRR/NAM HAVE TRENDED DRIER AND WINDIER THE PAST FEW HOURS. IN
FACT...LATEST HRRR DROPS DEWPOINTS INTO THE TEENS OVER NORTHERN EL
PASO COUNTY BY EARLY AFTERNOON...WHICH SUGGESTS FAIRLY DEEP
MIXING...THOUGH MODEL SURFACE/BL WINDS NEVER GET MUCH ABOVE 15
KNOTS. MAX TEMPS CONTINUE ON THE HOT SIDE...VERY SIMILAR TO
YESTERDAY. OVERNIGHT...CONVECTION LINGERS IN THE DEEPER MOISTURE
OVER THE FAR EASTERN PLAINS PAST SUNSET...THOUGH MOST AREAS SHOULD
SEE TSRA END BY MIDNIGHT AS POTENTIAL MCS LIFTS NORTHEAST INTO NEB.
SURFACE FRONT SHOULD GET A SOUTHWESTWARD SHOVE BY DEPARTING
CONVECTION...WITH LOW LEVEL MOISTURE SLOSHING BACK TO THE I-25
CORRIDOR AND EASTERN MOUNTAINS BY EARLY SATURDAY MORNING.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 343 AM MDT FRI JUN 14 2013
SOME CHANGES TO THE EXTENDED FOR THE WEEKEND INTO EARLY NEXT WEEK.
MODEL SOLUTIONS HAVE AN UPPER LEVEL RIDGE ACROSS THE ROCKIES
SATURDAY THROUGH TUESDAY...WITH SEVERAL DISTURBANCES MOVING ACROSS THE
REGION UNDER THE RIDGE. THE MAIN MODEL DIFFERENCES ARE IN THE
AMOUNT AND TYPE OF CONVECTION THAT MAY BE POSSIBLE ACROSS THE
PLAINS. MOISTURE WILL BE THE BIGGEST COMPLICATION AND WILL
DETERMINE HOW MUCH PRECIPITATION FALLS WITH THUNDERSTORM ACTIVITY.
MOISTURE STILL LOOKS MODEST ON SATURDAY AND MODEL SOLUTIONS ARE
HINTING THAT THUNDERSTORM ACTIVITY MAY BE LIMITED. MODELS DEVELOP
THUNDERSTORMS OVER THE MOUNTAINS BY SATURDAY AFTERNOON...WITH SOME
MOVEMENT OVER THE PALMER DIVIDE AND RATON MESA THROUGH THE
EVENING. LIGHTNING AND STRONG WIND GUSTS...POSSIBLY AS HIGH WAS 50
MPH...WILL BE THE MAIN THREATS...WITH VERY LITTLE PRECIPITATION
ACTUALLY FALLING.
MODELS A BIT MORE IMPRESSIVE WITH PRECIPITATION CHANCES SUNDAY
THROUGH TUESDAY. MOISTURE WILL ADVECT NORTHWARD OUT OF THE DESERT
SOUTHWEST WHICH SHOULD LEAD TO MORE WIDESPREAD SHOWER AND
THUNDERSTORM ACTIVITY. EXPECT THUNDERSTORMS TO DEVELOP BY LATE
MORNING EACH DAY OVER THE MOUNTAINS...AND SPREAD EAST INTO THE
I-25 CORRIDOR BY THE AFTERNOON. THE GFS IS MOST IMPRESSIVE
DEVELOPING MCS EVENTS THAT PUSH EAST ACROSS THE PLAINS THROUGH THE
OVERNIGHT PERIODS. THIS WOULD BRING LOCALLY HEAVY RAINFALL UNDER
THE STORM SYSTEMS. FOR NOW HAVE WIDESPREAD LOW POPS ACROSS THE
REGION AND HOPEFULLY THE REGION SEES SOME BENEFICIAL RAINFALL.
AN UPPER LEVEL LOW WILL MOVE INTO THE PACIFIC NORTHWEST BY
WEDNESDAY WHICH WILL SPREAD STRONG DRY SOUTHWEST FLOW ACROSS THE
ROCKIES. THIS WILL LEAD TO DRY AND HOT CONDITIONS ACROSS COLORADO
ALONG WITH INCREASED RISK OF DANGEROUS FIRE WEATHER CONDITIONS.
AREAS OVER THE CONTINENTAL DIVIDE...SAN LUIS VALLEY AND EASTERN
MOUNTAINS WILL LIKELY SEE THE DANGEROUS CONDITIONS BY WEDNESDAY
AFTERNOON WHICH WILL SPREAD EAST ACROSS THE PLAINS FOR THURSDAY
AND FRIDAY. WE WILL CONTINUE TO MONITOR THE SITUATION FOR MID TO
LATE NEXT WEEK IN REGARDS TO FIRE WEATHER. MOZLEY
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1103 AM MDT FRI JUN 14 2013
KALS...ISOLATED HIGH BASED STORMS WILL DEVELOP OVER THE
SURROUNDING MOUNTAINS DURING THE AFTERNOON AND EARLY EVENING.
THREAT OF ANY CONVECTION NEAR KALS IS LOW AND DID NOT PUT ANY IN
TAFS. HOWEVER...OUTFLOWS FROM THE STORMS COULD AFFECT KALS.
KCOS AND KPUB...CLOUDS WILL GRADUALLY DISSIPATE...AND ANTICIPATE
CONVECTION IN THE VICINITY OF BOTH SITES DURING THE AFTERNOON AND
EARLY EVENING. NEARBY CONVECTION COULD PRODUCE GUSTY OUTFLOWS WHICH
MAY IMPACT TAF SITES. CURRENT TAFS HAVE A COLD FRONT PASSING
AROUND SUNRISE SATURDAY. HOWEVER...OUTFLOW FROM FRIDAY EVENING
CONVECTION COULD RESULT IN AN EARLIER FRONTAL PASSAGE. --PGW--
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...PJC
SHORT TERM...PETERSEN
LONG TERM...MOZLEY
AVIATION...PGW
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
946 AM MDT FRI JUN 14 2013
.UPDATE...
&&
.SHORT TERM...WEAK FNT WAS MOVING ACROSS NERN CO THIS MORNING
WITH DRIER AIR BEHIND FNT. AT THIS POINT LOOKS LIKE BEST AREA FOR
TSTM DEVELOPMENT THIS AFTN WILL BE OVER THE PALMER DIVIDE TOWARDS
THE LIMON AREA. ALONG THE FRONT RANGE AND FURTHER NORTH EXPECTED
ISOLD TO WDLY SCT HIGHER BASED STORMS. THERE WILL BE SOME SVR
POTENTIAL MAINLY OVER ERN ELBERT AND LINCOLN COUNTIES.
.AVIATION...WK BNDRY WAS OVER DIA WITH WINDS SHIFTING TO NNE. BY
EARLY AFTN LATEST RAP SHOWS A WK DENVER CYCLONE DEVELOPING OVER
ERN DOUGLAS COUNTY WITH LOW LVL WINDS BECOMING MORE ELY AND
CONTINUING THRU MOST OF THE AFTN. AT THIS TIME LOOKS LIKE BEST CHC
FOR TSTMS WILL BE S AND SE OF DIA HOWEVER THERE STILL COULD BE
SOME ISOLD HIGHER BASED STORMS SO WILL KEEP VCNTY IN THE TAF. FOR
TONIGHT ANOTHER FNT WILL AFFECT THE AREA AFTER MIDNIGHT WITH
AREAS OF STRATUS DEVELOPING BY 12Z SAT. WINDS THIS EVENING WILL BE
SELY AND THEN BECOME MORE NLY AFTER MIDNIGHT.
&&
.FIRE WEATHER...HUMIDITY LEVELS WILL BE VERY LOW IN THE HIGHER
VALLEYS AND SRN FOOTHILLS HOWEVER WINDS WILL STAY BLO 20 MPH IN
MOST AREAS SO WILL NOT ISSUE ANY RED FLAG WARNINGS
&&
.HYDROLOGY...ISOLD HIGH BASED STORMS WILL BE POSSIBLE HOWEVER VERY
LITTLE RAINFALL WILL OCCUR.
&&
.PREV DISCUSSION... /ISSUED 349 AM MDT FRI JUN 14 2013/
SHORT TERM...SOUTHWEST FLOW ALOFT WILL CONTINUE TODAY. DRIER AIR
OVER UTAH AND WESTERN COLORADO WILL SHIFT EAST ACROSS THE STATE THIS
MORNING. DEW POINTS ARE ALREADY FALLING INTO 30S ACROSS THE DENVER
AREA. A LACK OF MOISTURE SHOULD KEEP ANY SHOWERS AND STORMS EAST OF
I-25. MOISTURE NOT THAT GREAT OVER EASTERN COLORADO EITHER WITH DEW
POINTS DROPPING INTO THE UPPER 30S TO LOWER 40S. A WEAK COLD FRONT
WITH ONLY FEW DEGREES OF COOLING WILL PUSH SOUTH ACROSS EASTERN
COLORADO THIS MORNING. THIS FRONT WILL STALL OVER THE PALMER DIVIDE
AND ALONG I-70 SOUTHEAST OF DENVER. CONVERGENCE ALONG THIS BOUNDARY
WILL LIKELY TRIGGER A FEW SHOWERS AND STORMS THIS AFTERNOON AND
EVENING. MOST OF THE MODELS ARE SHOWING SOME ACTIVITY IN THIS AREA.
TEMPERATURES IN THE UPPER 80S WITH DEW POINTS IN THE LOWER 40S YIELD
SURFACE BASED CAPES IN THE 400-800 J/KG RANGE. COULD GET A SEVERE
WIND GUST OR TWO DUE TO THE DRY SUB CLOUD LAYER...OTHERWISE NO
WIDESPREAD SEVERE WEATHER IS EXPECTED.
WINDS WILL TURN EASTERLY ACROSS NORTHEAST COLORADO THIS AFTERNOON
BEHIND THE FRONT. MOISTURE WILL START TO INCREASE AGAIN LATE THIS
AFTERNOON...BUT MORE SO THIS EVENING. THIS INCREASE IN MOISTURE
COMBINED WITH WEAK LIFT FROM A JET TO THE NORTH COULD PRODUCE A FEW
WEAK SHOWERS OR STORMS OVER NORTHEAST COLORADO. WILL HAVE 10-20 POPS
FOR THIS WITH HIGHER POPS ALONG I-70 SOUTHEAST OF DENVER WHERE THE
BETTER LIFT WILL BE.
STRONGER COLD FRONT WILL ENTER NORTHEAST COLORADO AFTER MIDNIGHT
TONIGHT. LOW CLOUDS WILL DEVELOP BEHIND THE FRONT AFTER 09Z AND THEN
SPREAD SOUTH ACROSS NORTHEAST COLORADO AROUND SUNRISE SATURDAY
MORNING.
LONG TERM...NOT MUCH IN TERMS OF ADJUSTMENT FROM THE PREVIOUS
FORECAST. SATURDAY WILL BE COOLER...FOLLOWING THE PASSAGE OF A
COLD FRONT FRIDAY NIGHT. THE NAM12 SPATIAL CROSS SECTIONS INDICATE
A FAIRLY THICK LAYER OF STRATUS IN THE LOWER LEVELS...WHICH WILL
LIKELY TAKE UNTIL LATE MORNING/EARLY AFTN TO COMPLETELY BURN OFF.
THE MDLS SOUNDINGS STILL SHOW VERY FAVORABLE CAPE IN THE AFTN
WITH VALUES IN THE 1200-1600 J/KG RANGE AT KDEN...KLIC AND KAKO.
MAIN QUESTION WILL BE IF AND WHEN THE CAP WILL BE ELIMINATED.
POTENTIAL FOR A FEW SEVERE THUNDERSTORMS WITH FAVORABLE SHEAR IN
PLACE. ON SUNDAY...IT MAY BE A LITTLE DRIER FROM THE FRONT RANGE
FOOTHILLS WESTWARD...BUT STILL A CHANCE OF TSTMS ESPECIALLY ACROSS
THE NORTHEASTERN PLAINS WHERE EVER THE LOW LEVEL THETA-E
CONVERGENCE OCCURS. ANOTHER COLD FRONT IS PROGGED TO MOVE INTO
NORTHEAST COLORADO SUNDAY NIGHT...WITH SIMILAR CONDITIONS TO
SATURDAY SETTING UP FOR MONDAY. THE AIRMASS WILL START TO DRY OUT
TUESDAY THROUGH THURSDAY AS THE SOUTHWESTERLY FLOW ALOFT OVER THE
STATE INCREASES...AND THE LOW LEVEL MOISTURE OVER THE NORTHEAST
PLAINS SHIFTS TO THE EAST. FIRE DANGER MAY AGAIN START TO ELEVATE
WITH HIGH TEMPERATURES PROGGED TO WARM INTO THE UPPER 80S BY
MIDWEEK.
AVIATION...SOUTH TO SOUTHWEST WINDS WITH GUSTS TO 20 KNOTS WILL
WEAKEN AND TURN WESTERLY AROUND 12Z. WINDS WILL CONTINUE TO TURN
CLOCKWISE DURING THE MORNING HOURS AS A WEAK COLD FRONT PUSHES
ACROSS THE AREA. AROUND 18Z...WINDS WILL BE EASTERLY AND REMAIN
EASTERLY THROUGH THE AFTERNOON. ISOLATED THUNDERSTORMS WILL
DEVELOP AFTER 19Z...MAINLY SOUTHEAST OF DENVER...THOUGH ONE CAN
NOT BE RULED OUT FOR THE DENVER AREA. THE DENVER AIRPORTS WILL
HAVE A BETTER CHANCE AT SEEING AN OUTFLOW BOUNDARY OR TWO.
ANOTHER COLD FRONT WILL PUSH THROUGH NORTHEAST COLORADO LATE
TONIGHT. LOW CLOUDS WITH CEILINGS BELOW 3000 FEET WILL DEVELOP
BEHIND THE FRONT LATE FRIDAY NIGHT AND CONTINUE INTO SATURDAY
MORNING.
HYDROLOGY...NO CONCERNS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RPK
LONG TERM....COOPER
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS PUEBLO CO
918 AM MDT FRI JUN 14 2013
.UPDATE...
ISSUED AT 916 AM MDT FRI JUN 14 2013
UPDATED THE GRIDS TO INCREASE CLOUD COVER ACROSS THE AREA OVER THE
NEXT FEW HOURS. -PJC
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 343 AM MDT FRI JUN 14 2013
SOUTHWEST FLOW ALOFT CONTINUES OVER THE AREA TODAY AND TONIGHT...AS
STRONG UPPER TROUGH LIFTS NORTHEAST FROM THE NORTHERN ROCKIES INTO
THE CANADIAN PRAIRIE. RATHER DIFFUSE SURFACE FRONT OVER THE EASTERN
PLAINS HAS BEEN GRADUALLY DRIFTING BACK EASTWARD THIS MORNING...WITH
WARMER/DRIER AIR MASS SPREADING EAST FROM THE MOUNTAINS ACROSS THE
I-25 CORRIDOR. OVERALL...WINDS TODAY LOOK LESS THAN THE PAST FEW
DAYS AS MID LEVEL FLOW DECREASES AND SURFACE GRADIENT RELAXES. FAR
SOUTHEAST PLAINS...MAINLY BACA COUNTY...COULD GET FAIRLY WINDY AHEAD
OF LEE SURFACE TROUGH...THOUGH RH REMAINS JUST ABOVE 15 PERCENT AND
WILL REFRAIN FROM ISSUING A FIRE WX HIGHLIGHT. WITH THIN PLUME OF
MID LEVEL MOISTURE OVER THE AREA ONCE AGAIN...EXPECT ANOTHER ROUND
OF MAINLY ISOLATED AFTERNOON AND EVENING THUNDERSTORMS...WITH BEST
CHANCES ALONG AND EAST OF A TRINIDAD TO LA JUNTA TO EADS
LINE...WHERE DEWPOINTS HOLD IN THE 40S AND CAPES PUSH ABOVE 1000
J/KG. SOME CONCERN ABOUT LOW RH AND BRIEFLY GUSTY WINDS OVER
TELLER/EL PASO COUNTIES THIS AFTERNOON...AS SUCCESSIVE RUNS OF THE
HRRR/NAM HAVE TRENDED DRIER AND WINDIER THE PAST FEW HOURS. IN
FACT...LATEST HRRR DROPS DEWPOINTS INTO THE TEENS OVER NORTHERN EL
PASO COUNTY BY EARLY AFTERNOON...WHICH SUGGESTS FAIRLY DEEP
MIXING...THOUGH MODEL SURFACE/BL WINDS NEVER GET MUCH ABOVE 15
KNOTS. MAX TEMPS CONTINUE ON THE HOT SIDE...VERY SIMILAR TO
YESTERDAY. OVERNIGHT...CONVECTION LINGERS IN THE DEEPER MOISTURE
OVER THE FAR EASTERN PLAINS PAST SUNSET...THOUGH MOST AREAS SHOULD
SEE TSRA END BY MIDNIGHT AS POTENTIAL MCS LIFTS NORTHEAST INTO NEB.
SURFACE FRONT SHOULD GET A SOUTHWESTWARD SHOVE BY DEPARTING
CONVECTION...WITH LOW LEVEL MOISTURE SLOSHING BACK TO THE I-25
CORRIDOR AND EASTERN MOUNTAINS BY EARLY SATURDAY MORNING.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 343 AM MDT FRI JUN 14 2013
SOME CHANGES TO THE EXTENDED FOR THE WEEKEND INTO EARLY NEXT WEEK.
MODEL SOLUTIONS HAVE AN UPPER LEVEL RIDGE ACROSS THE ROCKIES
SATURDAY THROUGH TUESDAY...WITH SEVERAL DISTURBANCES MOVING ACROSS THE
REGION UNDER THE RIDGE. THE MAIN MODEL DIFFERENCES ARE IN THE
AMOUNT AND TYPE OF CONVECTION THAT MAY BE POSSIBLE ACROSS THE
PLAINS. MOISTURE WILL BE THE BIGGEST COMPLICATION AND WILL
DETERMINE HOW MUCH PRECIPITATION FALLS WITH THUNDERSTORM ACTIVITY.
MOISTURE STILL LOOKS MODEST ON SATURDAY AND MODEL SOLUTIONS ARE
HINTING THAT THUNDERSTORM ACTIVITY MAY BE LIMITED. MODELS DEVELOP
THUNDERSTORMS OVER THE MOUNTAINS BY SATURDAY AFTERNOON...WITH SOME
MOVEMENT OVER THE PALMER DIVIDE AND RATON MESA THROUGH THE
EVENING. LIGHTNING AND STRONG WIND GUSTS...POSSIBLY AS HIGH WAS 50
MPH...WILL BE THE MAIN THREATS...WITH VERY LITTLE PRECIPITATION
ACTUALLY FALLING.
MODELS A BIT MORE IMPRESSIVE WITH PRECIPITATION CHANCES SUNDAY
THROUGH TUESDAY. MOISTURE WILL ADVECT NORTHWARD OUT OF THE DESERT
SOUTHWEST WHICH SHOULD LEAD TO MORE WIDESPREAD SHOWER AND
THUNDERSTORM ACTIVITY. EXPECT THUNDERSTORMS TO DEVELOP BY LATE
MORNING EACH DAY OVER THE MOUNTAINS...AND SPREAD EAST INTO THE
I-25 CORRIDOR BY THE AFTERNOON. THE GFS IS MOST IMPRESSIVE
DEVELOPING MCS EVENTS THAT PUSH EAST ACROSS THE PLAINS THROUGH THE
OVERNIGHT PERIODS. THIS WOULD BRING LOCALLY HEAVY RAINFALL UNDER
THE STORM SYSTEMS. FOR NOW HAVE WIDESPREAD LOW POPS ACROSS THE
REGION AND HOPEFULLY THE REGION SEES SOME BENEFICIAL RAINFALL.
AN UPPER LEVEL LOW WILL MOVE INTO THE PACIFIC NORTHWEST BY
WEDNESDAY WHICH WILL SPREAD STRONG DRY SOUTHWEST FLOW ACROSS THE
ROCKIES. THIS WILL LEAD TO DRY AND HOT CONDITIONS ACROSS COLORADO
ALONG WITH INCREASED RISK OF DANGEROUS FIRE WEATHER CONDITIONS.
AREAS OVER THE CONTINENTAL DIVIDE...SAN LUIS VALLEY AND EASTERN
MOUNTAINS WILL LIKELY SEE THE DANGEROUS CONDITIONS BY WEDNESDAY
AFTERNOON WHICH WILL SPREAD EAST ACROSS THE PLAINS FOR THURSDAY
AND FRIDAY. WE WILL CONTINUE TO MONITOR THE SITUATION FOR MID TO
LATE NEXT WEEK IN REGARDS TO FIRE WEATHER. MOZLEY
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 343 AM MDT FRI JUN 14 2013
VFR CONDITIONS EXPECTED AT ALL TAF SITES TODAY AND
TONIGHT. EXPECT ISOLATED TSRA OVER THE REGION AFTER 18Z...LASTING
UNTIL 02Z. MOST STORMS WILL BE HIGH BASED...LEADING TO POTENTIAL FOR
GUSTY/ERRATIC WINDS TO 40-45 KTS WITH ANY OUTFLOWS. COULD ALSO SEE
SOME OUTFLOW WIND DRIVEN AREAS OF BLOWING DUST OVER THE EASTERN
PLAINS BY LATE AFTERNOON...ESPECIALLY AROUND KLAA.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...PJC
SHORT TERM...PETERSEN
LONG TERM...MOZLEY
AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
446 AM MDT FRI JUN 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 343 AM MDT FRI JUN 14 2013
SOUTHWEST FLOW ALOFT CONTINUES OVER THE AREA TODAY AND TONIGHT...AS
STRONG UPPER TROUGH LIFTS NORTHEAST FROM THE NORTHERN ROCKIES INTO
THE CANADIAN PRAIRIE. RATHER DIFFUSE SURFACE FRONT OVER THE EASTERN
PLAINS HAS BEEN GRADUALLY DRIFTING BACK EASTWARD THIS MORNING...WITH
WARMER/DRIER AIR MASS SPREADING EAST FROM THE MOUNTAINS ACROSS THE
I-25 CORRIDOR. OVERALL...WINDS TODAY LOOK LESS THAN THE PAST FEW
DAYS AS MID LEVEL FLOW DECREASES AND SURFACE GRADIENT RELAXES. FAR
SOUTHEAST PLAINS...MAINLY BACA COUNTY...COULD GET FAIRLY WINDY AHEAD
OF LEE SURFACE TROUGH...THOUGH RH REMAINS JUST ABOVE 15 PERCENT AND
WILL REFRAIN FROM ISSUING A FIRE WX HIGHLIGHT. WITH THIN PLUME OF
MID LEVEL MOISTURE OVER THE AREA ONCE AGAIN...EXPECT ANOTHER ROUND
OF MAINLY ISOLATED AFTERNOON AND EVENING THUNDERSTORMS...WITH BEST
CHANCES ALONG AND EAST OF A TRINIDAD TO LA JUNTA TO EADS
LINE...WHERE DEWPOINTS HOLD IN THE 40S AND CAPES PUSH ABOVE 1000
J/KG. SOME CONCERN ABOUT LOW RH AND BRIEFLY GUSTY WINDS OVER
TELLER/EL PASO COUNTIES THIS AFTERNOON...AS SUCCESSIVE RUNS OF THE
HRRR/NAM HAVE TRENDED DRIER AND WINDIER THE PAST FEW HOURS. IN
FACT...LATEST HRRR DROPS DEWPOINTS INTO THE TEENS OVER NORTHERN EL
PASO COUNTY BY EARLY AFTERNOON...WHICH SUGGESTS FAIRLY DEEP
MIXING...THOUGH MODEL SURFACE/BL WINDS NEVER GET MUCH ABOVE 15
KNOTS. MAX TEMPS CONTINUE ON THE HOT SIDE...VERY SIMILAR TO
YESTERDAY. OVERNIGHT...CONVECTION LINGERS IN THE DEEPER MOISTURE
OVER THE FAR EASTERN PLAINS PAST SUNSET...THOUGH MOST AREAS SHOULD
SEE TSRA END BY MIDNIGHT AS POTENTIAL MCS LIFTS NORTHEAST INTO NEB.
SURFACE FRONT SHOULD GET A SOUTHWESTWARD SHOVE BY DEPARTING
CONVECTION...WITH LOW LEVEL MOISTURE SLOSHING BACK TO THE I-25
CORRIDOR AND EASTERN MOUNTAINS BY EARLY SATURDAY MORNING.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 343 AM MDT FRI JUN 14 2013
SOME CHANGES TO THE EXTENDED FOR THE WEEKEND INTO EARLY NEXT WEEK.
MODEL SOLUTIONS HAVE AN UPPER LEVEL RIDGE ACROSS THE ROCKIES
SATURDAY THROUGH TUESDAY...WITH SEVERAL DISTURBANCES MOVING ACROSS THE
REGION UNDER THE RIDGE. THE MAIN MODEL DIFFERENCES ARE IN THE
AMOUNT AND TYPE OF CONVECTION THAT MAY BE POSSIBLE ACROSS THE
PLAINS. MOISTURE WILL BE THE BIGGEST COMPLICATION AND WILL
DETERMINE HOW MUCH PRECIPITATION FALLS WITH THUNDERSTORM ACTIVITY.
MOISTURE STILL LOOKS MODEST ON SATURDAY AND MODEL SOLUTIONS ARE
HINTING THAT THUNDERSTORM ACTIVITY MAY BE LIMITED. MODELS DEVELOP
THUNDERSTORMS OVER THE MOUNTAINS BY SATURDAY AFTERNOON...WITH SOME
MOVEMENT OVER THE PALMER DIVIDE AND RATON MESA THROUGH THE
EVENING. LIGHTNING AND STRONG WIND GUSTS...POSSIBLY AS HIGH WAS 50
MPH...WILL BE THE MAIN THREATS...WITH VERY LITTLE PRECIPITATION
ACTUALLY FALLING.
MODELS A BIT MORE IMPRESSIVE WITH PRECIPITATION CHANCES SUNDAY
THROUGH TUESDAY. MOISTURE WILL ADVECT NORTHWARD OUT OF THE DESERT
SOUTHWEST WHICH SHOULD LEAD TO MORE WIDESPREAD SHOWER AND
THUNDERSTORM ACTIVITY. EXPECT THUNDERSTORMS TO DEVELOP BY LATE
MORNING EACH DAY OVER THE MOUNTAINS...AND SPREAD EAST INTO THE
I-25 CORRIDOR BY THE AFTERNOON. THE GFS IS MOST IMPRESSIVE
DEVELOPING MCS EVENTS THAT PUSH EAST ACROSS THE PLAINS THROUGH THE
OVERNIGHT PERIODS. THIS WOULD BRING LOCALLY HEAVY RAINFALL UNDER
THE STORM SYSTEMS. FOR NOW HAVE WIDESPREAD LOW POPS ACROSS THE
REGION AND HOPEFULLY THE REGION SEES SOME BENEFICIAL RAINFALL.
AN UPPER LEVEL LOW WILL MOVE INTO THE PACIFIC NORTHWEST BY
WEDNESDAY WHICH WILL SPREAD STRONG DRY SOUTHWEST FLOW ACROSS THE
ROCKIES. THIS WILL LEAD TO DRY AND HOT CONDITIONS ACROSS COLORADO
ALONG WITH INCREASED RISK OF DANGEROUS FIRE WEATHER CONDITIONS.
AREAS OVER THE CONTINENTAL DIVIDE...SAN LUIS VALLEY AND EASTERN
MOUNTAINS WILL LIKELY SEE THE DANGEROUS CONDITIONS BY WEDNESDAY
AFTERNOON WHICH WILL SPREAD EAST ACROSS THE PLAINS FOR THURSDAY
AND FRIDAY. WE WILL CONTINUE TO MONITOR THE SITUATION FOR MID TO
LATE NEXT WEEK IN REGARDS TO FIRE WEATHER. MOZLEY
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 343 AM MDT FRI JUN 14 2013
VFR CONDITIONS EXPECTED AT ALL TAF SITES TODAY AND
TONIGHT. EXPECT ISOLATED TSRA OVER THE REGION AFTER 18Z...LASTING
UNTIL 02Z. MOST STORMS WILL BE HIGH BASED...LEADING TO POTENTIAL FOR
GUSTY/ERRATIC WINDS TO 40-45 KTS WITH ANY OUTFLOWS. COULD ALSO SEE
SOME OUTFLOW WIND DRIVEN AREAS OF BLOWING DUST OVER THE EASTERN
PLAINS BY LATE AFTERNOON...ESPECIALLY AROUND KLAA.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...PETERSEN
LONG TERM...MOZLEY
AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS MIAMI FL
738 PM EDT SAT JUN 15 2013
.AVIATION...
GENERALLY QUIET NEXT 48 HOURS IN STORE FOR TERMINALS...WITH ONLY
ISOLATED SHOWERS EXPECTED SUNDAY AFTERNOON. VFR CONDITIONS WILL
PREVAIL WITH MAINLY SCATTERED CU BELOW CI DEBRIS. LIGHT WINDS
TONIGHT WILL BECOME ESE AT 10 KNOTS ON SUNDAY. GULF BREEZE SHOULD
REACH KAPF BTWN 16-19Z SUNDAY...TRANSITIONING WINDS TO WSW AROUND
10 KTS.
&&
.PREV DISCUSSION... /ISSUED 202 PM EDT SAT JUN 15 2013/
DISCUSSION...
HIGH PRESSURE BUILDING OVER THE AREA, HAS ALLOWED THE UPPER
ATMOSPHERE TO WARM AND DRY OUT SOME. THIS HAS INHIBITED ANY
CONVECTIVE CELLS SO FAR TODAY. THE GFS KEEPS ANYTHING THAT IS ABLE
TO DEVELOP, NEAR THE LAKE REGION. THE ECMWF IS NOT MUCH DIFFERENT.
WITH LAPSE RATES LOWER THAN YESTERDAY, AS WELL AS PWATS DROPPING TO
BELOW 1.5 INCHES, THIS IS BELIEVABLE. THE HRRR IS SHOWING
CONVECTION TRYING TO FIRE IN THE WESTERN HALF OF THE CWA THIS
EVENING, BUT AM NOT BITING OFF ENTIRELY ON THIS SCENARIO. HAVE
KEPT LOW END CHANCE POPS OVER GLADE/HENDRY/AND COLLIER COUNTIES,
AND SLIGHT CHANCE OVER MUCH OF THE REST OF THE CWA, BUT THIS MAY
WELL EVEN BE OVERKILL TODAY. BUT, ONLY TIME WILL TELL. IF IT IS
NOT ABLE TO GO TODAY, IT WILL PROBABLY HAVE A HARD TIME GOING
TOMORROW AS WELL, AS CONDITIONS WILL ONLY BE DRIER, WITH A
SOMEWHAT STRONGER UPPER LEVEL HIGH. HAVE KEPT LOW END CHANCE OVER
THE GULF COAST FOR TOMORROW WITH THIS PACKAGE, BUT AGAIN, THAT MAY
BE TOO HIGH.
THE HIGH CONTINUES FOR THE BEGINNING OF THE WEEK IN THE UPPER
LEVELS. IN THE LOWER LEVELS, HOWEVER, THE BERMUDA HIGH STRENGTHENS
ONCE AGAIN, BRINGING A MORE EASTERLY FLOW BACK TO SOUTH FLORIDA,
AND THEREFORE INCREASING MOISTURE. SO, THE GULF COAST WILL KEEP
CHANCE POPS INTO AT LEAST MID NEXT WEEK AND PROBABLY THROUGH THE
END OF THE WEEK, BY WHICH TIME, MORE OF SOUTH FLORIDA MAY SEE
CONVECTION FIRING.
THERE IS A TROPICAL WAVE THAT MODELS SHOW WILL BE WELL TO THE
SOUTH. IF IT KEEPS THAT TRACK, IT SHOULD NOT HAVE AN IMPACT ON
SOUTH FLORIDA WEATHER. IF IT DOES COME CLOSER, IT WILL, OF COURSE,
CHANGE THE FORECAST TO MOST LIKELY ADDITIONAL COVERAGE OF SHOWERS
AND THUNDERSTORMS FROM MID TO LATE NEXT WEEK.
MARINE...
CONDITIONS SHOULD REMAIN FAIRLY QUIET INTO THE BEGINNING OF THE
WEEK. THE BERMUDA HIGH IS FORECAST TO STRENGTHEN, WHICH COULD
ALLOW SEAS TO BUILD BY MID WEEK. OTHERWISE, EASTERLY WINDS WILL
KICK IN BY THE BEGINNING OF THE WEEK FOR THE ATLANTIC WATERS.
THERE IS A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY.
FIRE WEATHER...
THERE IS AN UPPER LEVEL RIDGE THAT IS BUILDING OVER SOUTH FLORIDA.
THIS SHOULD LEAD TO INCREASING STABILITY FOR A COUPLE OF DAYS. THE
BERMUDA HIGH WILL STRENGTHEN FOR THE BEGINNING OF THE WEEK,
ALLOWING AN EASTERLY FLOW TO BEGIN TO BEING MORE MOISTURE BACK
INTO THE AREA, AND THUS MORE CONVECTIVE ACTIVITY NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 75 85 75 86 / 10 20 10 20
FORT LAUDERDALE 79 87 78 87 / 10 20 10 20
MIAMI 78 88 78 88 / 10 20 10 20
NAPLES 76 88 75 88 / 20 20 20 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...13/SI
AVIATION/RADAR...23/SK
AREA FORECAST DISCUSSION
NWS MIAMI FL
1058 AM EDT FRI JUN 14 2013
.UPDATE...
FAIRLY QUIET MORNING WITH JUST A COUPLE OF ISOLATED LIGHT SHOWERS
TRYING TO DEVELOP ALONG THE GULF COAST. THE HRRR DOES SHOW
CONVECTION FIRING AFTER 18Z TODAY, WHICH DOES AGREE WITH THE GFS
AND ECMWF. SO HAVE KEPT 30 POPS IN FOR THE EASTERN HALF OF THE
FORECAST AREA.
&&
.PREV DISCUSSION... /ISSUED 732 AM EDT FRI JUN 14 2013/
AVIATION...
ALTHOUGH THE SHRA/TSTM COVERAGE WILL BE REDUCED COMPARED TO THE PAST
FEW DAYS DUE TO SOME DRIER AIR FILTERING IN ACROSS THE AREA ON THE
BACK-SIDE OF AN UPPER TROUGH...LIGHT WESTERLY LOW-LEVEL FLOW
COMBINED WITH A SUFFICIENT AMOUNT OF MOISTURE AND DAYTIME HEATING
WILL BE ENOUGH TO TRIGGER AFTERNOON SHRA/TSTMS TODAY. THE BEST CHANCE
FOR THIS ISLTD/SCT ACTIVITY WILL FAVOR THE EAST COAST TAF SITES
THROUGH THE AFTERNOON/EARLY EVENING PERIODS. WILL KEEP THE VCTS IN
THIS TAF PACKAGE FOR THE EAST COAST SITES. THIS ACTIVITY WILL TREND
DOWN THROUGH THE EARLY/MID EVENING HOURS WITH ANOTHER QUIET NIGHT
ANTICIPATED TONIGHT INTO SATURDAY MORNING
AVIATION...BNB/AG
PREV DISCUSSION... /ISSUED 416 AM EDT FRI JUN 14 2013/
DISCUSSION...
ONLY A FEW SHOWERS REMAIN ACROSS THE ATLANTIC WATERS THIS MORNING
AND SHOULD REMAIN OFFSHORE. WEAK MID LEVEL TROUGH WILL CONTINUE TO
PUSH OFFSHORE THE ATLANTIC COAST THROUGH THE DAY. HOWEVER...ANOTHER
ROUND OF AFTERNOON SHOWERS AND THUNDERSTORMS ARE EXPECTED ACROSS
THE AREA TODAY BEFORE A SHORT DRYING PERIOD THROUGH THE FIRST PART
OF THE WEEKEND. WEAK SOUTHWESTERLY FLOW WILL PREVAIL AGAIN THROUGH
THE DAY BUT SHOULD NOT BE STRONG ENOUGH TO OVERTAKE A DEVELOPING
EAST COAST SEA BREEZE. THIS SHOULD ALLOW SHOWERS AND THUNDERSTORMS
TO DEVELOP MAINLY ALONG THE EAST COASTAL AREAS AND LOCAL HIGH
RESOLUTION MODELS ARE DEPICTING THIS. BELIEVE GUIDANCE IS WAY TOO
LOW FOR POPS...SO KEPT 20 POP AREA WIDE WITH 30 POP ALONG THE EAST
COAST METRO AREAS.
AS THE MID LEVEL TROUGH MOVES OUT...THIS WILL ALLOW RIDGING TO BUILD
ACROSS THE AREA FROM THE GULF OF MEXICO WHICH WILL ALLOW A DRIER
AIR MASS TO PUSH INTO THE AREA FOR THE WEEKEND. STEERING FLOW WILL
STILL BE WEAK WHICH SHOULD ALLOW A SEA BREEZE TO SET UP. AS A
RESULT...COULD NOT RULE OUT A FEW ISOLATED THUNDERSTORMS MAINLY
ACROSS THE NORTHWEST INTERIOR DURING THE PEAK HEATING HOURS
SATURDAY AND SUNDAY.
MONDAY THROUGH MIDWEEK...EASTERLY FLOW WILL BECOME RE-ESTABLISHED
ACROSS THE SOUTH FLORIDA PENINSULA. AT THE SAME TIME...A TROPICAL
WAVE IS STILL EXPECTED TO PUSH WEST-NORTHWEST ACROSS THE YUCATAN
PENINSULA AND INTO THE BAY OF CAMPECHE. AS IT DOES...IT WILL ENHANCE
CHANCES FOR SHOWERS AND THUNDERSTORMS ACROSS SOUTH FLORIDA WITH THE
BEST CHANCES TUESDAY AFTERNOON.
SLIGHTLY DRIER AIR WILL THEN FILTER INTO THE AREA THROUGH THE
LATTER HALF OF THE WEEK AS WEAK RIDGING SETS UP ACROSS THE WESTERN
ATLANTIC BEHIND THE PASSING TROPICAL WAVE. HOWEVER...SLIGHT
CHANCES FOR AFTERNOON SHOWERS AND THUNDERSTORMS WILL STILL
PREVAIL. TEMPERATURES THROUGH THE UPCOMING WEEK ARE EXPECTED TO
RUN SLIGHTLY ABOVE NORMAL WITH MAXIMUM HEAT INDEX READINGS
APPROACHING 100 DEGREES ACROSS THE EAST COAST METRO AREAS.
AVIATION...
ALTHOUGH THE SHRA/TSTM COVERAGE WILL BE REDUCED COMPARED TO THE PAST
FEW DAYS DUE TO SOME DRIER AIR FILTERING IN ACROSS THE AREA ON THE
BACK-SIDE OF AN UPPER TROUGH...LIGHT WESTERLY LOW-LEVEL FLOW
COMBINED WITH A SUFFICIENT AMOUNT OF MOISTURE AND DAYTIME HEATING
WILL BE ENOUGH TO TRIGGER AFTERNOON SHRA/TSTMS TODAY. THE BEST CHANCE
FOR THIS ISLTD/SCT ACTIVITY WILL FAVOR THE EAST COAST TAF SITES
THROUGH THE AFTERNOON/EARLY EVENING PERIODS. WILL KEEP THE VCTS IN
THIS TAF PACKAGE FOR THE EAST COAST SITES. THIS ACTIVITY WILL TREND
DOWN THROUGH THE EARLY/MID EVENING HOURS WITH ANOTHER QUIET NIGHT
ANTICIPATED TONIGHT INTO SATURDAY MORNING.
MARINE...
MAINLY BENIGN MARINE CONDITIONS ARE EXPECTED ACROSS THE AREA
WATERS OUTSIDE OF SHOWERS AND THUNDERSTORMS AS WINDS REMAIN AT
AROUND 10 KNOTS OR LESS THROUGH SATURDAY. FOR SUNDAY INTO EARLY
NEXT WEEK, EASTERLY FLOW RETURNS WITH WINDS AROUND 10 TO 15 KNOTS
AND SEAS AROUND 3 FEET ACROSS THE ATLANTIC WATERS AS A TROPICAL
WAVE PASSES BY WELL TO THE SOUTH.
FIRE WEATHER...
SLIGHTLY DRIER AIR IS EXPECTED TO PUSH INTO THE SOUTH FLORIDA AREA
INTO THE WEEKEND. HOWEVER...MINIMUM RELATIVE HUMIDITY VALUES
SHOULD STILL REMAIN ABOVE CRITICAL THRESHOLDS AND REMAIN THAT WAY
THROUGH NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 87 74 89 78 / 30 10 10 10
FORT LAUDERDALE 89 76 89 80 / 30 10 10 10
MIAMI 90 76 90 78 / 30 10 10 10
NAPLES 87 75 90 76 / 20 - 10 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...13/SI
AVIATION/RADAR...85/AG
AREA FORECAST DISCUSSION
NWS LINCOLN IL
124 PM CDT FRI JUN 14 2013
.DISCUSSION...
ISSUED 124 PM CDT FRI JUN 14 2013
ISSUED MINOR UPDATE TO ADD A STRIPE OF 50 POPS TO THE FAR
SOUTHWEST CWA THIS AFTERNOON PRIMARILY AFFECTING RUSHVILLE TO
JACKSONVILLE AND WEST. CLUSTER OF SHOWERS AND EMBEDDED TSTMS HAS
NOW EDGED EAST OF THE MISSISSIPPI RIVER...AND ALTHOUGH IR IMAGERY
SHOWS CLOUD TOPS BEGINNING TO WARM...FEEL SYSTEM HAS ENOUGH
ORGANIZATION TO GRAZE THE CORNER OF THE CWA BEFORE DISSIPATING
EARLY THIS EVENING.
25
&&
.AVIATION...
ISSUED 1240 PM CDT FRI JUN 14 2013
VFR CONDITIONS EXPECTED OUTSIDE OF THUNDERSTORMS NEXT 24 HRS.
FIRST IN A SERIES OF TSTM COMPLEXES TO AFFECT THE MIDWEST OVER THE
NEXT COUPLE DAYS...IS SHIFTING EAST ALONG THE IA/MO BORDER. WITH
SFC RIDGE AXIS AND DRIER AIR STILL OVER CENTRAL IL FEEL MUCH OF
THIS WILL DISSIPATE AS IT PUSHES EAST OF THE MS RIVER THIS
AFTERNOON...LEAVING A VEIL OF HIGH CLOUDS OVER THE TERMINALS INTO
THIS EVENING. MOST MODEL GUIDANCE SUPPORTS ANOTHER COMPLEX
DEVELOPING OVER IA TONIGHT AND SHIFTS E/SE INTO NORTHERN AND
CENTRAL IA SATURDAY MORNING...IN A WEAKENING MODE AS LOW LEVEL JET
SUPPORT WEAKENS AFTER 12Z. THUS HAVE MOST CONFIDENCE IN THIS
ACTIVITY AFFECTING PIA...WHILE FARTHER SITES TO THE SOUTHEAST JUST
HAVE VCTS THROUGH THE REMAINDER OF THE MORNING. LIGHT/VRB WINDS
UNDER THE RIDGE AXIS THIS AFTERNOON WILL GRADUALLY COME AROUND TO
THE SOUTHEAST THIS EVENING BUT REMAIN LIGHT UNDER 10 KTS
OVERNIGHT. HIGHER SPEEDS OF 10+ KTS ARE EXPECTED AFTER 12Z SAT
AS GRADIENT DEVELOPS AHEAD OF A LOW PRESSURE WAVE SHIFTING ACROSS
IA.
25
&&
.PREV DISCUSSION...
ISSUED 1041 AM CDT FRI JUN 14 2013
15Z SURFACE MAP PLACED A RIDGE AXIS FROM LK SUPERIOR SOUTH THROUGH
CENTRAL IL AND INTO THE LOWER MISSISSIPPI VALLEY. THIS PROVIDED
LIGHT WINDS ALONG WITH MOSTLY SUNNY SKIES AND MILD
TEMPS/DEWPOINTS. UPSTREAM CONVECTION OVER CENTRAL IA/NRN MO
DEVELOPED AHEAD OF SHORTWAVE IN EASTERN NEB WHICH WAS TOPPING THE
UPPER RIDGE. THIS COMPLEX OF STORMS WAS BEING MAINTAINED FROM THE
SOUTHWEST BY A HIGH THETA-E FEED OF MOISTURE-RICH AIR FROM EASTERN
KS. THIS ACTIVITY SHOULD TEND TO DIMINISH AS IT SHIFTS EAST THIS
AFTERNOON AWAY FROM BEST SUPPORT AND INTO DRIER AIR ASSOCIATED
WITH THE LINGERING RIDGE. MOST HI-RES GUIDANCE SUPPORTS THIS IDEA
WITH THE HRRR BEING A NOTABLE EXCEPTION...BRINGING SCATTERED T-STORMS
INTO WEST CENTRAL IL AFTER 21Z. WILL KEEP A DRY FORECAST ACROSS
THE WEST FOR NOW BUT MONITOR TRENDS FOR THE LATE AFTERNOON.
OTHERWISE...SKIES TO BE MOSTLY SUNNY OVER THE EAST WITH INCREASING
HIGH CLOUDS OVER THE WESTERN CWA. HIGHS ON TRACK TO BE A COUPLE
DEGREES COOLER THAN YESTERDAY DUE TO SHALLOWER MIXING DEPTH UNDER
RIDGE AND ASSOCIATED LIGHTER WIND REGIME.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1241 PM CDT FRI JUN 14 2013
.DISCUSSION...
ISSUED 1041 AM CDT FRI JUN 14 2013
15Z SURFACE MAP PLACED A RIDGE AXIS FROM LK SUPERIOR SOUTH THROUGH
CENTRAL IL AND INTO THE LOWER MISSISSIPPI VALLEY. THIS PROVIDED
LIGHT WINDS ALONG WITH MOSTLY SUNNY SKIES AND MILD
TEMPS/DEWPOINTS. UPSTREAM CONVECTION OVER CENTRAL IA/NRN MO
DEVELOPED AHEAD OF SHORTWAVE IN EASTERN NEB WHICH WAS TOPPING THE
UPPER RIDGE. THIS COMPLEX OF STORMS WAS BEING MAINTAINED FROM THE
SOUTHWEST BY A HIGH THETA-E FEED OF MOISTURE-RICH AIR FROM EASTERN
KS. THIS ACTIVITY SHOULD TEND TO DIMINISH AS IT SHIFTS EAST THIS
AFTERNOON AWAY FROM BEST SUPPORT AND INTO DRIER AIR ASSOCIATED
WITH THE LINGERING RIDGE. MOST HI-RES GUIDANCE SUPPORTS THIS IDEA
WITH THE HRRR BEING A NOTABLE EXCEPTION...BRINGING SCATTERED T-STORMS
INTO WEST CENTRAL IL AFTER 21Z. WILL KEEP A DRY FORECAST ACROSS
THE WEST FOR NOW BUT MONITOR TRENDS FOR THE LATE AFTERNOON.
OTHERWISE...SKIES TO BE MOSTLY SUNNY OVER THE EAST WITH INCREASING
HIGH CLOUDS OVER THE WESTERN CWA. HIGHS ON TRACK TO BE A COUPLE
DEGREES COOLER THAN YESTERDAY DUE TO SHALLOWER MIXING DEPTH UNDER
RIDGE AND ASSOCIATED LIGHTER WIND REGIME.
&&
.AVIATION...
ISSUED 1240 PM CDT FRI JUN 14 2013
VFR CONDITIONS EXPECTED OUTSIDE OF THUNDERSTORMS NEXT 24 HRS.
FIRST IN A SERIES OF TSTM COMPLEXES TO AFFECT THE MIDWEST OVER THE
NEXT COUPLE DAYS...IS SHIFTING EAST ALONG THE IA/MO BORDER. WITH
SFC RIDGE AXIS AND DRIER AIR STILL OVER CENTRAL IL FEEL MUCH OF
THIS WILL DISSIPATE AS IT PUSHES EAST OF THE MS RIVER THIS
AFTERNOON...LEAVING A VEIL OF HIGH CLOUDS OVER THE TERMINALS INTO
THIS EVENING. MOST MODEL GUIDANCE SUPPORTS ANOTHER COMPLEX
DEVELOPING OVER IA TONIGHT AND SHIFTS E/SE INTO NORTHERN AND
CENTRAL IA SATURDAY MORNING...IN A WEAKENING MODE AS LOW LEVEL JET
SUPPORT WEAKENS AFTER 12Z. THUS HAVE MOST CONFIDENCE IN THIS
ACTIVITY AFFECTING PIA...WHILE FARTHER SITES TO THE SOUTHEAST JUST
HAVE VCTS THROUGH THE REMAINDER OF THE MORNING. LIGHT/VRB WINDS
UNDER THE RIDGE AXIS THIS AFTERNOON WILL GRADUALLY COME AROUND TO
THE SOUTHEAST THIS EVENING BUT REMAIN LIGHT UNDER 10 KTS
OVERNIGHT. HIGHER SPEEDS OF 10+ KTS ARE EXPECTED AFTER 12Z SAT
AS GRADIENT DEVELOPS AHEAD OF A LOW PRESSURE WAVE SHIFTING ACROSS
IA.
25
&&
.PREV DISCUSSION...
ISSUED 330 AM CDT FRI JUN 14 2013
SHORT TERM...TODAY THROUGH MONDAY NIGHT
WILL USE A BLEND OF THE 00Z MODELS FOR THIS FORECAST WITH ONE MORE
NICE DAY TODAY WITH PARTLY TO MOSTLY SUNNY SKIES THEN BECOMING MORE
UNSETTLED THIS WEEKEND INTO MON BEFORE DRIER AND COOLER WEATHER
RETURNS TUE/WED. MET AND MAV GUIDANCE TEMPS SIMILAR THROUGH SUNDAY
THOUGH DID GO A BIT WARMER FOR HIGHS TODAY SINCE TEMPS HAVE BEEN
RUNNING ABOVE GUIDANCE TEMPS PAST FEW DAYS AND EXPECTING A FAIR
AMOUNT OF SUNSHINE YET TODAY. SPC CONTINUES SLIGHT RISK OF SEVERE
STORMS IN DAY2 OUTLOOK FOR SAT NW HALF OF CWA AND WILL NEED TO
ADDRESS THIS.
1023 MB CANADIAN HIGH PRESSURE NORTH OF LAKE SUPERIOR OVER CENTRAL
ONTARIO WAS RIDGING SOUTHWARD INTO THE MS VALLEY AND PROVIDING
NEARLY CLEAR SKIES OVER CENTRAL AND EASTERN IL WITH A FEW PATCHES
OF HIGH CLOUDS OVER WEST CENTRAL IL. COOLER TEMPS WERE IN THE
UPPER 50S AND LOWER 60S WITH MORE COMFORTABLE DEWPOINTS IN THE LOW
TO MID 50S WITH LIGHT WINDS.
MODELS WEAKEN HIGH PRESSURE OVER CENTRAL ONTARIO SSE INTO LOWER MI
AND OHIO AT 1019 MB THIS EVENING AS UPPER LEVEL HEIGHTS RISE A BIT
OVER IL AS UPPER LEVEL TROF OVER THE ATLANTIC STATES PULLS FURTHER
AWAY FROM IL. SCATTERED CUMULUS CLOUDS TO DEVELOP BY MIDDAY WITH
INCREASING HIGH CLOUDS ESPECIALLY IL RIVER VALLEY WHERE SKIES
BECOME PARTLY SUNNY THIS AFTERNOON...AND MOSTLY SUNNY OVER EASTERN
IL. HIGHS GENERALLY IN THE LOWER 80S WITH AREAS FROM I-74 NE
CLOSER TO 80F AS ENE WINDS LESS THAN 10 MPH PREVAIL TODAY.
MOST AREAS SHOULD STAY DRY YET THIS EVENING WITH JUST SMALL
CHANCES OF SHOWERS AND THUNDERSTORMS MOVING INTO THE IL RIVER
VALLEY LATER THIS EVENING. THEN INCREASING CHANCES OF SHOWERS AND
THUNDERSTORMS OVERNIGHT FROM I-55 NW WITH LIKELY POPS NW OF THE IL
RIVER LATE TONIGHT. THIS DUE TO MCS TO RIDE OVER TOP OF UPPER
LEVEL RIDGE OVER THE EASTERN PLAINS AND MOVE FROM IA INTO
CENTRAL/NW IL OVERNIGHT INTO SAT MORNING. EASTERN AND SE IL SHOULD
STAY DRY THROUGH THE NIGHT. LOWS TONIGHT IN THE LOWER 60S AND COOLEST
OVER EAST CENTRAL IL. SPC KEEPS SLIGHT RISK OVER CENTRAL AND
WESTERN IA TONIGHT.
BETTER CHANCES OF CONVECTION SAT OVER CENTRAL AND NORTHERN AREAS
WHILE JUST SLIGHT CHANCE IN SE IL SAT AFTERNOON. MCS TO WEAKEN
OVER CENTRAL IL SAT MORNING BUT SCATTERED THUNDERSTORMS TO
REDEVELOP IN UNSTABLE AIR MASS SAT AFTERNOON AND CONTINUE SAT NIGHT
WHEN YET ANOTHER MCS TO IMPACT PARTS OF CENTRAL/NORTHERN IL. SPC
HAS SLIGHT CHANCE FROM RANTOUL TO SPRINGFIELD NW LATER SAT AFTERNOON
AND SAT NIGHT WITH 15% RISK OF DAMAGING WIND GUSTS AND LARGE HAIL
POSSIBLE.
FRONTAL BOUNDARY TO PUSH SOUTHWARD THROUGH CENTRAL/SE IL SUNDAY
AND STALL FOR A TIME EARLY NEXT WEEK BEFORE PUSHING FURTHER SOUTH
LATER MON AND MON NIGHT. HAVE HIGHER CHANCES OF SHOWERS AND
THUNDERSTORMS OVER SOUTHERN HALF CWA SUNDAY INTO MONDAY. SPC HAS
5% RISK OF SEVERE STORMS ON SUNDAY OVER CENTRAL/SE IL. CONVECTION
CHANCES TO DIMINISH FROM NW TO SE LATER MON INTO MONDAY EVENING.
LONG TERM...TUESDAY THROUGH THURSDAY
CANADIAN HIGH PRESSURE SETTLING INTO THE GREAT LAKES REGION BY
TUE TO RETURN DRY AND COOLER AND LESS HUMID WEATHER TUE AND WED.
CONVECTION CHANCES RETURN TO THE MS VALLEY BY THU BUT MODELS
DIFFER ON TIMING OF RETURNING CONVECTION CHANCES TO IL AND STAYED
CLOSE TO ALLBLEND POPS WHICH ARE JUST SLIGHT OVER WESTERN AREAS
THU.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1042 AM CDT FRI JUN 14 2013
.DISCUSSION...
ISSUED 1041 AM CDT FRI JUN 14 2013
15Z SURFACE MAP PLACED A RIDGE AXIS FROM LK SUPERIOR SOUTH THROUGH
CENTRAL IL AND INTO THE LOWER MISSISSIPPI VALLEY. THIS PROVIDED
LIGHT WINDS ALONG WITH MOSTLY SUNNY SKIES AND MILD
TEMPS/DEWPOINTS. UPSTREAM CONVECTION OVER CENTRAL IA/NRN MO
DEVELOPED AHEAD OF SHORTWAVE IN EASTERN NEB WHICH WAS TOPPING THE
UPPER RIDGE. THIS COMPLEX OF STORMS WAS BEING MAINTAINED FROM THE
SOUTHWEST BY A HIGH THETA-E FEED OF MOISTURE-RICH AIR FROM EASTERN
KS. THIS ACTIVITY SHOULD TEND TO DIMINISH AS IT SHIFTS EAST THIS
AFTERNOON AWAY FROM BEST SUPPORT AND INTO DRIER AIR ASSOCIATED
WITH THE LINGERING RIDGE. MOST HI-RES GUIDANCE SUPPORTS THIS IDEA
WITH THE HRRR BEING A NOTABLE EXCEPTION...BRINGING SCATTERED T-STORMS
INTO WEST CENTRAL IL AFTER 21Z. WILL KEEP A DRY FORECAST ACROSS
THE WEST FOR NOW BUT MONITOR TRENDS FOR THE LATE AFTERNOON.
OTHERWISE...SKIES TO BE MOSTLY SUNNY OVER THE EAST WITH INCREASING
HIGH CLOUDS OVER THE WESTERN CWA. HIGHS ON TRACK TO BE A COUPLE
DEGREES COOLER THAN YESTERDAY DUE TO SHALLOWER MIXING DEPTH UNDER
RIDGE AND ASSOCIATED LIGHTER WIND REGIME.
25
&&
.AVIATION...
ISSUED 620 AM CDT FRI JUN 14 2013
LITTLE TO WORRY ABOUT THROUGH ABOUT MID EVENING...WITH MAINLY
INCREASING HIGH CLOUDS AND NORTHEAST WINDS GRADUALLY SWINGING
AROUND TO THE SOUTHEAST. MAIN CONCERN WILL BE WITH OVERNIGHT
STORM CHANCES...AS A CONVECTIVE COMPLEX FORMS ACROSS IOWA/
NORTHERN MISSOURI THIS EVENING AND MOVES SOUTHEAST. CURRENTLY
THINK THAT KPIA IS THE ONLY CENTRAL ILLINOIS TAF SITE TO HAVE A
DECENT SHOT OF TSRA AFTER 06Z...BUT HAVE INCLUDED VCTS AT
KBMI/KSPI LATE AS SOME OF THE MODELS HINT THE STORMS MAY MAKE IT
THAT FAR EAST BY SUNRISE. HOWEVER...THE BETTER CHANCES OF STORMS
OVER CENTRAL ILLINOIS APPEAR TO BE AFTER THE CURRENT TAF FORECAST
PERIOD.
GEELHART
&&
.PREV DISCUSSION...
ISSUED 330 AM CDT FRI JUN 14 2013
SHORT TERM...TODAY THROUGH MONDAY NIGHT
WILL USE A BLEND OF THE 00Z MODELS FOR THIS FORECAST WITH ONE MORE
NICE DAY TODAY WITH PARTLY TO MOSTLY SUNNY SKIES THEN BECOMING MORE
UNSETTLED THIS WEEKEND INTO MON BEFORE DRIER AND COOLER WEATHER
RETURNS TUE/WED. MET AND MAV GUIDANCE TEMPS SIMILAR THROUGH SUNDAY
THOUGH DID GO A BIT WARMER FOR HIGHS TODAY SINCE TEMPS HAVE BEEN
RUNNING ABOVE GUIDANCE TEMPS PAST FEW DAYS AND EXPECTING A FAIR
AMOUNT OF SUNSHINE YET TODAY. SPC CONTINUES SLIGHT RISK OF SEVERE
STORMS IN DAY2 OUTLOOK FOR SAT NW HALF OF CWA AND WILL NEED TO
ADDRESS THIS.
1023 MB CANADIAN HIGH PRESSURE NORTH OF LAKE SUPERIOR OVER CENTRAL
ONTARIO WAS RIDGING SOUTHWARD INTO THE MS VALLEY AND PROVIDING
NEARLY CLEAR SKIES OVER CENTRAL AND EASTERN IL WITH A FEW PATCHES
OF HIGH CLOUDS OVER WEST CENTRAL IL. COOLER TEMPS WERE IN THE
UPPER 50S AND LOWER 60S WITH MORE COMFORTABLE DEWPOINTS IN THE LOW
TO MID 50S WITH LIGHT WINDS.
MODELS WEAKEN HIGH PRESSURE OVER CENTRAL ONTARIO SSE INTO LOWER MI
AND OHIO AT 1019 MB THIS EVENING AS UPPER LEVEL HEIGHTS RISE A BIT
OVER IL AS UPPER LEVEL TROF OVER THE ATLANTIC STATES PULLS FURTHER
AWAY FROM IL. SCATTERED CUMULUS CLOUDS TO DEVELOP BY MIDDAY WITH
INCREASING HIGH CLOUDS ESPECIALLY IL RIVER VALLEY WHERE SKIES
BECOME PARTLY SUNNY THIS AFTERNOON...AND MOSTLY SUNNY OVER EASTERN
IL. HIGHS GENERALLY IN THE LOWER 80S WITH AREAS FROM I-74 NE
CLOSER TO 80F AS ENE WINDS LESS THAN 10 MPH PREVAIL TODAY.
MOST AREAS SHOULD STAY DRY YET THIS EVENING WITH JUST SMALL
CHANCES OF SHOWERS AND THUNDERSTORMS MOVING INTO THE IL RIVER
VALLEY LATER THIS EVENING. THEN INCREASING CHANCES OF SHOWERS AND
THUNDERSTORMS OVERNIGHT FROM I-55 NW WITH LIKELY POPS NW OF THE IL
RIVER LATE TONIGHT. THIS DUE TO MCS TO RIDE OVER TOP OF UPPER
LEVEL RIDGE OVER THE EASTERN PLAINS AND MOVE FROM IA INTO
CENTRAL/NW IL OVERNIGHT INTO SAT MORNING. EASTERN AND SE IL SHOULD
STAY DRY THROUGH THE NIGHT. LOWS TONIGHT IN THE LOWER 60S AND COOLEST
OVER EAST CENTRAL IL. SPC KEEPS SLIGHT RISK OVER CENTRAL AND
WESTERN IA TONIGHT.
BETTER CHANCES OF CONVECTION SAT OVER CENTRAL AND NORTHERN AREAS
WHILE JUST SLIGHT CHANCE IN SE IL SAT AFTERNOON. MCS TO WEAKEN
OVER CENTRAL IL SAT MORNING BUT SCATTERED THUNDERSTORMS TO
REDEVELOP IN UNSTABLE AIR MASS SAT AFTERNOON AND CONTINUE SAT NIGHT
WHEN YET ANOTHER MCS TO IMPACT PARTS OF CENTRAL/NORTHERN IL. SPC
HAS SLIGHT CHANCE FROM RANTOUL TO SPRINGFIELD NW LATER SAT AFTERNOON
AND SAT NIGHT WITH 15% RISK OF DAMAGING WIND GUSTS AND LARGE HAIL
POSSIBLE.
FRONTAL BOUNDARY TO PUSH SOUTHWARD THROUGH CENTRAL/SE IL SUNDAY
AND STALL FOR A TIME EARLY NEXT WEEK BEFORE PUSHING FURTHER SOUTH
LATER MON AND MON NIGHT. HAVE HIGHER CHANCES OF SHOWERS AND
THUNDERSTORMS OVER SOUTHERN HALF CWA SUNDAY INTO MONDAY. SPC HAS
5% RISK OF SEVERE STORMS ON SUNDAY OVER CENTRAL/SE IL. CONVECTION
CHANCES TO DIMINISH FROM NW TO SE LATER MON INTO MONDAY EVENING.
LONG TERM...TUESDAY THROUGH THURSDAY
CANADIAN HIGH PRESSURE SETTLING INTO THE GREAT LAKES REGION BY
TUE TO RETURN DRY AND COOLER AND LESS HUMID WEATHER TUE AND WED.
CONVECTION CHANCES RETURN TO THE MS VALLEY BY THU BUT MODELS
DIFFER ON TIMING OF RETURNING CONVECTION CHANCES TO IL AND STAYED
CLOSE TO ALLBLEND POPS WHICH ARE JUST SLIGHT OVER WESTERN AREAS
THU.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1246 PM CDT FRI JUN 14 2013
.UPDATE...
ISSUED AT 1212 PM CDT FRI JUN 14 2013
APPEARS THE MOIST AIR IS WINNING OUT AS THE SMALL MCS THAT WAS IN
SW IA EARLIER THIS MORNING HAS SHIFTED INTO SE IA AND EXTREME NORTHEAST
MO. HAVE MADE A QUICK UPDATE TO THE GRIDS TO INCREASE POPS TO
LIKELY IN OUR SOUTHWEST CWA INTO THIS AFTERNOON. NONE OF THE
MODELS INCLUDING THE MESO MODELS INDICATED THIS MCS MOVING INTO
THE DVN CWA SO WILL CONTINUE TO NOWCAST AND UPDATE AS NEEDED.
UPDATE ISSUED AT 1033 AM CDT FRI JUN 14 2013
THUNDERSTORMS WERE OCCURRING IN SW IA AND NW MO ON THE NOSE OF A
LOW LEVEL JET AND STRONG MOISTURE GRADIENT...AND ON THE EDGE OF A
STRONG CAP. 850 MB DEWPOINT AT KTOP WAS +18C BUT DRIER AIR WAS NOTED
FARTHER TO THE NORTHEAST WITH KMPX -4C AND KDVN +7. THE BETTER
FORCING WILL REMAIN WEST AND SOUTHWEST OF THE DVN CWA BUT ISOLATED
TO SCATTERED SHOWERS AND THUNDERSTORMS WILL OCCUR IN OUR WESTERN
CWA LATE THIS MORNING INTO THE AFTERNOON HOURS.
UPDATE ISSUED AT 642 AM CDT FRI JUN 14 2013
RADAR SHOWS THE CONVECTION IN CENTRAL IOWA CONTINUES BUT IS
RAPIDLY WEAKENING AS IT MOVES INTO DRIER AIR AND AWAY FROM THE
BETTER SUPPORT. RAP TRENDS CONTINUE TO SHOW A WEAK BUT RESPECTABLE
THETA E GRADIENT WHICH IS HELPING TO MAINTAIN THE CONVECTION.
BASED ON RADAR AND RAP TRENDS SOME OF THIS CONVECTION WILL GET
INTO THE WESTERN CWFA THIS MORNING AS LIGHT SHOWERS OR SPRINKLES
BEFORE DISSIPATING.
WATER VAPOR AND THE RAP SHOW TWO VORT MAXES CURRENTLY MOVING
ACROSS NEBRASKA. THESE FEATURES WILL DRIVE THE DIURNAL CONVECTION
THIS AFTERNOON THAT WILL EVENTUALLY EVOLVE INTO ANOTHER NOCTURNAL
MCS LATE TONIGHT. ..08..
&&
.SYNOPSIS...
ISSUED AT 308 AM CDT FRI JUN 14 2013
06Z SFC ANALYSIS HAS A HIGH RUNNING FROM LAKE SUPERIOR INTO THE
LOWER MISSISSIPPI VALLEY. LOWS WERE IN SOUTHEAST MONTANA AND
SOUTHEAST COLORADO. THE MAIN SYNOPTIC FRONT RAN FROM SOUTHWEST
KANSAS INTO THE DEEP SOUTH. DEW POINTS WERE IN THE 60S AND 70S FROM
THE CENTRAL PLAINS INTO THE DEEP SOUTH WITH 40S AND 50S ACROSS THE
GREAT LAKES AND UPPER MISSISSIPPI VALLEY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM CDT FRI JUN 14 2013
THE MCS AND LIFT TOOLS INDICATE THE CURRENT CONVECTION FROM
SOUTHWEST MN INTO NORTHERN IOWA IS ASSOCIATED WITH A THETA E
GRADIENT AND VORT MAX. THIS CONVECTION WILL SLOWLY DISSIPATE AS IT
MOVES AWAY FROM THE BETTER MOISTURE AND INTO THE RIDGE. THUS THE
MORNING HOURS WILL BE DRY WITH AN INCREASE IN CLOUD COVER.
HOWEVER...THE CLOUD COVER WILL SLOWLY THIN AS IT HITS THE RIDGE SO
THERE SHOULD BE A RESPECTABLE AMOUNT OF SUNSHINE TO HELP WARM UP.
RAP TRENDS ALONG WITH THE MCS AND LIFT TOOLS INDICATE THE VORT MAX
MOVING THROUGH SOUTHERN NEBRASKA WILL PROBABLY BE THE MECHANISM TO
GENERATE DIURNAL CONVECTION THIS AFTERNOON. THIS CONVECTION SHOULD
DEVELOP OR MOVE INTO THE WESTERN CWFA AROUND MID AFTERNOON AND
SLOWLY OVERSPREAD THE WESTERN HALF OF THE CWFA THROUGH LATE
AFTERNOON.
TONIGHT...THE MCS AND LIFT TOOLS INDICATE THE DIURNAL CONVECTION IS
EXPECTED TO EVOLVE INTO ANOTHER NOCTURNAL MCS ACROSS THE AREA.
CONVECTION SHOULD REMAIN ISOLATED TO SCATTERED UNTIL CLOSER TO
MIDNIGHT WHEN THE LLJ VEERS INTO THE CWFA. AT THIS TIME UPSCALE
GROWTH AND AN INCREASE IN AREAL COVERAGE ACROSS THE CWFA WILL BE
SEEN. PWATS ARE EXPECTED TO BE OVER 1.5 INCHES SO THERE WOULD BE A
THREAT OF HEAVY RAIN IF STORMS MOVE OVER THE SAME AREA. THE GROUND
IS REASONABLY DRY SO THIS INITIAL ROUND OF RAIN SHOULD NOT CAUSE
MUCH IN THE WAY OF PROBLEMS. ..08..
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 308 AM CDT FRI JUN 14 2013
INITIAL FOCUS IS ON THUNDERSTORM POTENTIAL FOR SATURDAY THAT WILL
HAVE A RISK FOR BOTH SEVERE STORMS AND HEAVY RAINFALL. TRANSITION TO
NW FLOW TO THEN BRING COOLER AND DRIER WEATHER FOR AT LEAST THE
FIRST HALF OF NEXT WEEK.
NOCTURNAL MCS WILL LIKELY BE ON-GOING SATURDAY MORNING...WHERE
MODELS ARE IN GENERAL AGREEMENT DEPICTING LOW PRESSURE NEAR OMAHA
WITH A WARM...OR INITIALLY STATIONARY FRONT REACHING EAST ALONG THE
IA/MO BORDER. ALL ARE SUGGESTING A RIDGE TOPPING SHORTWAVE THAT WILL
PUSH THROUGH DURING THE DAY...WHICH SENDS THE SURFACE LOW
EAST-NORTHEAST ACROSS THE FORECAST AREA AND NUDGES THE SURFACE
BOUNDARY NORTHWARD. ON THE WARM SIDE OF THIS BOUNDARY...MODEL CAPES
ARE ROUGHLY IN THE RANGE OF 3500 TO OVER 4000 J/KG WITH BULK SHEAR
VALUES AROUND 40 TO 45 KTS...SUFFICIENT FOR SEVERE STORMS AND
SUPERCELLS ESPECIALLY ALONG THE BOUNDARY IN THE AFTERNOON INTO
EVENING. SPC HAS THE ENTIRE FORECAST AREA IN A SLIGHT RISK FOR DAY
2. MUCH WILL DEPEND ON THE TIMING OF THE EXITING OR DISSIPATING
OVERNIGHT MCS AND RELATED BOUNDARIES AND CLOUD COVER. FOR NOW...WILL
CONTINUE A BROAD-BRUSH APPROACH WITH LIKELY POPS FOR THUNDERSTORMS
OVER THE ENTIRE AREA. HIGHS WILL LIKELY BE LIMITED TO THE UPPER 70S
ACROSS THE NORTH...WHILE THE SOUTH SHOULD AT LEAST PUSH INTO THE 80S
WITH DEWPOINTS INTO THE 70S...DEPENDING ON TRENDS WITH CLOUD COVER AND
FRONTAL TIMING. ELEVATED SW FLOW OF 15 TO 30 KTS WILL ADVECT A HIGH
PW AIRMASS...AROUND 1.5 TO 1.8 OR 150 PERCENT OF NORMAL OVER THE
ENTIRE AREA...THAT WILL SUPPORT HEAVY RAINFALL IN HP TYPE SUPERCELLS OR
WHERE STORMS TRAIN ALONG BOUNDARIES. THE RESULTING FLASH FLOODING
THREAT WILL BE HIGHLY DEPENDENT ON RAINFALL COVERAGE AND AMOUNTS
FROM THE PREVIOUS EVENT. FOR NOW...HAVE WIDESPREAD QPF AMOUNTS OF A
QUARTER TO HALF INCH...BUT FULLY EXPECT STORM SCALE TOTALS OF 1 TO 2
INCHES.
SATURDAY NIGHT...A STRONGER SHORTWAVE...INITIALLY OVER THE TX BEND
REGION AT 00Z...IS SHOWN RIDING NORTH AND THEN SWEEPING EAST ACROSS
THE FORECAST AREA IN THE FIRST HALF OF THE NIGHT...PROVIDING RENEWED
FOCUS FOR LIKELY ANOTHER MCS AND POSSIBLE HEAVY RAINFALL AND LIKELY
POPS ARE MAINTAINED. THIS SYSTEM IS EXPECTED TO SUPPRESS THE FRONTAL
BOUNDARY BACK TO JUST SOUTH OF THE FORECAST AREA SUNDAY. THE CLOSE
PROXIMITY OF THIS BOUNDARY...AND A STRONG UPPER SHORTWAVE THEN
ADVANCING FROM THE NW WILL KEEP SHOWERS AND THUNDERSTORMS IN THE
FORECAST THROUGH MONDAY...BUT THE HEAVY RAINFALL THREAT WILL BE
DIMINISHED. A NW FLOW AND HIGH PRESSURE THEN SUGGESTS DRY CONDITIONS
THROUGH AT LEAST WED WITH NEAR TO SLIGHTLY BELOW NORMAL
TEMPERATURES. MODEL CONSENSUS HAS CHANCES FOR SHOWERS AND
THUNDERSTORMS RETURNING TO THE FORECAST THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1242 PM CDT FRI JUN 14 2013
VFR CONDS THIS AFTERNOON WITH THUNDERSTORMS IN SOUTHEAST IA MOVING
TO THE SOUTHEAST. KBRL IS ON THE EDGE OF THE CLUSTER OF STORMS.
OTHERWISE...AT ALL TAF SITES SHOWERS AND THUNDERSTORMS WILL
ARRIVE THIS EVENING AND OVERNIGHT...THEN DIMINISH A BIT SATURDAY
MORNING. MVFR/BRIEF IFR CONDS CAN BE EXPECTED IN THE STRONGER
STORMS. SOUTHEAST WINDS AROUND 10 KNOTS OR LESS THIS AFTERNOON AND
TONIGHT THEN BECOMING SOUTH 10 TO 15 KNOTS ON SATURDAY.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...HAASE
SYNOPSIS...08
SHORT TERM...08
LONG TERM...SHEETS
AVIATION...HAASE
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1217 PM CDT FRI JUN 14 2013
.UPDATE...
ISSUED AT 1212 PM CDT FRI JUN 14 2013
APPEARS THE MOIST AIR IS WINNING OUT AS THE SMALL MCS THAT WAS IN
SW IA EARLIER THIS MORNING HAS SHIFTED INTO SE IA AND EXTREME NORTHEAST
MO. HAVE MADE A QUICK UPDATE TO THE GRIDS TO INCREASE POPS TO
LIKELY IN OUR SOUTHWEST CWA INTO THIS AFTERNOON. NONE OF THE
MODELS INCLUDING THE MESO MODELS INDICATED THIS MCS MOVING INTO
THE DVN CWA SO WILL CONTINUE TO NOWCAST AND UPDATE AS NEEDED.
UPDATE ISSUED AT 1033 AM CDT FRI JUN 14 2013
THUNDERSTORMS WERE OCCURRING IN SW IA AND NW MO ON THE NOSE OF A
LOW LEVEL JET AND STRONG MOISTURE GRADIENT...AND ON THE EDGE OF A
STRONG CAP. 850 MB DEWPOINT AT KTOP WAS +18C BUT DRIER AIR WAS NOTED
FARTHER TO THE NORTHEAST WITH KMPX -4C AND KDVN +7. THE BETTER
FORCING WILL REMAIN WEST AND SOUTHWEST OF THE DVN CWA BUT ISOLATED
TO SCATTERED SHOWERS AND THUNDERSTORMS WILL OCCUR IN OUR WESTERN
CWA LATE THIS MORNING INTO THE AFTERNOON HOURS.
UPDATE ISSUED AT 642 AM CDT FRI JUN 14 2013
RADAR SHOWS THE CONVECTION IN CENTRAL IOWA CONTINUES BUT IS
RAPIDLY WEAKENING AS IT MOVES INTO DRIER AIR AND AWAY FROM THE
BETTER SUPPORT. RAP TRENDS CONTINUE TO SHOW A WEAK BUT RESPECTABLE
THETA E GRADIENT WHICH IS HELPING TO MAINTAIN THE CONVECTION.
BASED ON RADAR AND RAP TRENDS SOME OF THIS CONVECTION WILL GET
INTO THE WESTERN CWFA THIS MORNING AS LIGHT SHOWERS OR SPRINKLES
BEFORE DISSIPATING.
WATER VAPOR AND THE RAP SHOW TWO VORT MAXES CURRENTLY MOVING
ACROSS NEBRASKA. THESE FEATURES WILL DRIVE THE DIURNAL CONVECTION
THIS AFTERNOON THAT WILL EVENTUALLY EVOLVE INTO ANOTHER NOCTURNAL
MCS LATE TONIGHT. ..08..
&&
.SYNOPSIS...
ISSUED AT 308 AM CDT FRI JUN 14 2013
06Z SFC ANALYSIS HAS A HIGH RUNNING FROM LAKE SUPERIOR INTO THE
LOWER MISSISSIPPI VALLEY. LOWS WERE IN SOUTHEAST MONTANA AND
SOUTHEAST COLORADO. THE MAIN SYNOPTIC FRONT RAN FROM SOUTHWEST
KANSAS INTO THE DEEP SOUTH. DEW POINTS WERE IN THE 60S AND 70S FROM
THE CENTRAL PLAINS INTO THE DEEP SOUTH WITH 40S AND 50S ACROSS THE
GREAT LAKES AND UPPER MISSISSIPPI VALLEY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM CDT FRI JUN 14 2013
THE MCS AND LIFT TOOLS INDICATE THE CURRENT CONVECTION FROM
SOUTHWEST MN INTO NORTHERN IOWA IS ASSOCIATED WITH A THETA E
GRADIENT AND VORT MAX. THIS CONVECTION WILL SLOWLY DISSIPATE AS IT
MOVES AWAY FROM THE BETTER MOISTURE AND INTO THE RIDGE. THUS THE
MORNING HOURS WILL BE DRY WITH AN INCREASE IN CLOUD COVER.
HOWEVER...THE CLOUD COVER WILL SLOWLY THIN AS IT HITS THE RIDGE SO
THERE SHOULD BE A RESPECTABLE AMOUNT OF SUNSHINE TO HELP WARM UP.
RAP TRENDS ALONG WITH THE MCS AND LIFT TOOLS INDICATE THE VORT MAX
MOVING THROUGH SOUTHERN NEBRASKA WILL PROBABLY BE THE MECHANISM TO
GENERATE DIURNAL CONVECTION THIS AFTERNOON. THIS CONVECTION SHOULD
DEVELOP OR MOVE INTO THE WESTERN CWFA AROUND MID AFTERNOON AND
SLOWLY OVERSPREAD THE WESTERN HALF OF THE CWFA THROUGH LATE
AFTERNOON.
TONIGHT...THE MCS AND LIFT TOOLS INDICATE THE DIURNAL CONVECTION IS
EXPECTED TO EVOLVE INTO ANOTHER NOCTURNAL MCS ACROSS THE AREA.
CONVECTION SHOULD REMAIN ISOLATED TO SCATTERED UNTIL CLOSER TO
MIDNIGHT WHEN THE LLJ VEERS INTO THE CWFA. AT THIS TIME UPSCALE
GROWTH AND AN INCREASE IN AREAL COVERAGE ACROSS THE CWFA WILL BE
SEEN. PWATS ARE EXPECTED TO BE OVER 1.5 INCHES SO THERE WOULD BE A
THREAT OF HEAVY RAIN IF STORMS MOVE OVER THE SAME AREA. THE GROUND
IS REASONABLY DRY SO THIS INITIAL ROUND OF RAIN SHOULD NOT CAUSE
MUCH IN THE WAY OF PROBLEMS. ..08..
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 308 AM CDT FRI JUN 14 2013
INITIAL FOCUS IS ON THUNDERSTORM POTENTIAL FOR SATURDAY THAT WILL
HAVE A RISK FOR BOTH SEVERE STORMS AND HEAVY RAINFALL. TRANSITION TO
NW FLOW TO THEN BRING COOLER AND DRIER WEATHER FOR AT LEAST THE
FIRST HALF OF NEXT WEEK.
NOCTURNAL MCS WILL LIKELY BE ON-GOING SATURDAY MORNING...WHERE
MODELS ARE IN GENERAL AGREEMENT DEPICTING LOW PRESSURE NEAR OMAHA
WITH A WARM...OR INITIALLY STATIONARY FRONT REACHING EAST ALONG THE
IA/MO BORDER. ALL ARE SUGGESTING A RIDGE TOPPING SHORTWAVE THAT WILL
PUSH THROUGH DURING THE DAY...WHICH SENDS THE SURFACE LOW
EAST-NORTHEAST ACROSS THE FORECAST AREA AND NUDGES THE SURFACE
BOUNDARY NORTHWARD. ON THE WARM SIDE OF THIS BOUNDARY...MODEL CAPES
ARE ROUGHLY IN THE RANGE OF 3500 TO OVER 4000 J/KG WITH BULK SHEAR
VALUES AROUND 40 TO 45 KTS...SUFFICIENT FOR SEVERE STORMS AND
SUPERCELLS ESPECIALLY ALONG THE BOUNDARY IN THE AFTERNOON INTO
EVENING. SPC HAS THE ENTIRE FORECAST AREA IN A SLIGHT RISK FOR DAY
2. MUCH WILL DEPEND ON THE TIMING OF THE EXITING OR DISSIPATING
OVERNIGHT MCS AND RELATED BOUNDARIES AND CLOUD COVER. FOR NOW...WILL
CONTINUE A BROAD-BRUSH APPROACH WITH LIKELY POPS FOR THUNDERSTORMS
OVER THE ENTIRE AREA. HIGHS WILL LIKELY BE LIMITED TO THE UPPER 70S
ACROSS THE NORTH...WHILE THE SOUTH SHOULD AT LEAST PUSH INTO THE 80S
WITH DEWPOINTS INTO THE 70S...DEPENDING ON TRENDS WITH CLOUD COVER AND
FRONTAL TIMING. ELEVATED SW FLOW OF 15 TO 30 KTS WILL ADVECT A HIGH
PW AIRMASS...AROUND 1.5 TO 1.8 OR 150 PERCENT OF NORMAL OVER THE
ENTIRE AREA...THAT WILL SUPPORT HEAVY RAINFALL IN HP TYPE SUPERCELLS OR
WHERE STORMS TRAIN ALONG BOUNDARIES. THE RESULTING FLASH FLOODING
THREAT WILL BE HIGHLY DEPENDENT ON RAINFALL COVERAGE AND AMOUNTS
FROM THE PREVIOUS EVENT. FOR NOW...HAVE WIDESPREAD QPF AMOUNTS OF A
QUARTER TO HALF INCH...BUT FULLY EXPECT STORM SCALE TOTALS OF 1 TO 2
INCHES.
SATURDAY NIGHT...A STRONGER SHORTWAVE...INITIALLY OVER THE TX BEND
REGION AT 00Z...IS SHOWN RIDING NORTH AND THEN SWEEPING EAST ACROSS
THE FORECAST AREA IN THE FIRST HALF OF THE NIGHT...PROVIDING RENEWED
FOCUS FOR LIKELY ANOTHER MCS AND POSSIBLE HEAVY RAINFALL AND LIKELY
POPS ARE MAINTAINED. THIS SYSTEM IS EXPECTED TO SUPPRESS THE FRONTAL
BOUNDARY BACK TO JUST SOUTH OF THE FORECAST AREA SUNDAY. THE CLOSE
PROXIMITY OF THIS BOUNDARY...AND A STRONG UPPER SHORTWAVE THEN
ADVANCING FROM THE NW WILL KEEP SHOWERS AND THUNDERSTORMS IN THE
FORECAST THROUGH MONDAY...BUT THE HEAVY RAINFALL THREAT WILL BE
DIMINISHED. A NW FLOW AND HIGH PRESSURE THEN SUGGESTS DRY CONDITIONS
THROUGH AT LEAST WED WITH NEAR TO SLIGHTLY BELOW NORMAL
TEMPERATURES. MODEL CONSENSUS HAS CHANCES FOR SHOWERS AND
THUNDERSTORMS RETURNING TO THE FORECAST THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 642 AM CDT FRI JUN 14 2013
CONVECTION IN CENTRAL IOWA WILL DISSIPATE THROUGH 18Z/14 AS IT
ENCOUNTERS DRIER AIR OVER EASTERN IOWA. VFR WX IS EXPECTED
THROUGH 00Z/15. TSRA WILL DEVELOP AFT 20Z/14 THAT WILL BECOME MORE
NUMEROUS ACROSS EASTERN IOWA/NORTHERN ILLINOIS AFT 00Z/15. AFT
00Z/15 VFR WX IS EXPECTED TO CONTINUE. HOWEVER...THE TSRA ARE
EXPECTED TO EVOLVE INTO A TSRA COMPLEX THAT MAY RESULT IN MVFR
CONDITIONS AFT 06Z/15. ..08..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...HAASE
SYNOPSIS...08
SHORT TERM...08
LONG TERM...SHEETS
AVIATION...08
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1039 AM CDT FRI JUN 14 2013
.UPDATE...
ISSUED AT 1033 AM CDT FRI JUN 14 2013
THUNDERSTORMS WERE OCCURRING IN SW IA AND NW MO ON THE NOSE OF A
LOW LEVEL JET AND STRONG MOISTURE GRADIENT...AND ON THE EDGE OF A
STRONG CAP. 850 MB DEWPOINT AT KTOP WAS +18C BUT DRIER AIR WAS NOTED
FARTHER TO THE NORTHEAST WITH KMPX -4C AND KDVN +7. THE BETTER
FORCING WILL REMAIN WEST AND SOUTHWEST OF THE DVN CWA BUT ISOLATED
TO SCATTERED SHOWERS AND THUNDERSTORMS WILL OCCUR IN OUR WESTERN
CWA LATE THIS MORNING INTO THE AFTERNOON HOURS.
UPDATE ISSUED AT 642 AM CDT FRI JUN 14 2013
RADAR SHOWS THE CONVECTION IN CENTRAL IOWA CONTINUES BUT IS
RAPIDLY WEAKENING AS IT MOVES INTO DRIER AIR AND AWAY FROM THE
BETTER SUPPORT. RAP TRENDS CONTINUE TO SHOW A WEAK BUT RESPECTABLE
THETA E GRADIENT WHICH IS HELPING TO MAINTAIN THE CONVECTION.
BASED ON RADAR AND RAP TRENDS SOME OF THIS CONVECTION WILL GET
INTO THE WESTERN CWFA THIS MORNING AS LIGHT SHOWERS OR SPRINKLES
BEFORE DISSIPATING.
WATER VAPOR AND THE RAP SHOW TWO VORT MAXES CURRENTLY MOVING
ACROSS NEBRASKA. THESE FEATURES WILL DRIVE THE DIURNAL CONVECTION
THIS AFTERNOON THAT WILL EVENTUALLY EVOLVE INTO ANOTHER NOCTURNAL
MCS LATE TONIGHT. ..08..
&&
.SYNOPSIS...
ISSUED AT 308 AM CDT FRI JUN 14 2013
06Z SFC ANALYSIS HAS A HIGH RUNNING FROM LAKE SUPERIOR INTO THE
LOWER MISSISSIPPI VALLEY. LOWS WERE IN SOUTHEAST MONTANA AND
SOUTHEAST COLORADO. THE MAIN SYNOPTIC FRONT RAN FROM SOUTHWEST
KANSAS INTO THE DEEP SOUTH. DEW POINTS WERE IN THE 60S AND 70S FROM
THE CENTRAL PLAINS INTO THE DEEP SOUTH WITH 40S AND 50S ACROSS THE
GREAT LAKES AND UPPER MISSISSIPPI VALLEY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM CDT FRI JUN 14 2013
THE MCS AND LIFT TOOLS INDICATE THE CURRENT CONVECTION FROM
SOUTHWEST MN INTO NORTHERN IOWA IS ASSOCIATED WITH A THETA E
GRADIENT AND VORT MAX. THIS CONVECTION WILL SLOWLY DISSIPATE AS IT
MOVES AWAY FROM THE BETTER MOISTURE AND INTO THE RIDGE. THUS THE
MORNING HOURS WILL BE DRY WITH AN INCREASE IN CLOUD COVER.
HOWEVER...THE CLOUD COVER WILL SLOWLY THIN AS IT HITS THE RIDGE SO
THERE SHOULD BE A RESPECTABLE AMOUNT OF SUNSHINE TO HELP WARM UP.
RAP TRENDS ALONG WITH THE MCS AND LIFT TOOLS INDICATE THE VORT MAX
MOVING THROUGH SOUTHERN NEBRASKA WILL PROBABLY BE THE MECHANISM TO
GENERATE DIURNAL CONVECTION THIS AFTERNOON. THIS CONVECTION SHOULD
DEVELOP OR MOVE INTO THE WESTERN CWFA AROUND MID AFTERNOON AND
SLOWLY OVERSPREAD THE WESTERN HALF OF THE CWFA THROUGH LATE
AFTERNOON.
TONIGHT...THE MCS AND LIFT TOOLS INDICATE THE DIURNAL CONVECTION IS
EXPECTED TO EVOLVE INTO ANOTHER NOCTURNAL MCS ACROSS THE AREA.
CONVECTION SHOULD REMAIN ISOLATED TO SCATTERED UNTIL CLOSER TO
MIDNIGHT WHEN THE LLJ VEERS INTO THE CWFA. AT THIS TIME UPSCALE
GROWTH AND AN INCREASE IN AREAL COVERAGE ACROSS THE CWFA WILL BE
SEEN. PWATS ARE EXPECTED TO BE OVER 1.5 INCHES SO THERE WOULD BE A
THREAT OF HEAVY RAIN IF STORMS MOVE OVER THE SAME AREA. THE GROUND
IS REASONABLY DRY SO THIS INITIAL ROUND OF RAIN SHOULD NOT CAUSE
MUCH IN THE WAY OF PROBLEMS. ..08..
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 308 AM CDT FRI JUN 14 2013
INITIAL FOCUS IS ON THUNDERSTORM POTENTIAL FOR SATURDAY THAT WILL
HAVE A RISK FOR BOTH SEVERE STORMS AND HEAVY RAINFALL. TRANSITION TO
NW FLOW TO THEN BRING COOLER AND DRIER WEATHER FOR AT LEAST THE
FIRST HALF OF NEXT WEEK.
NOCTURNAL MCS WILL LIKELY BE ON-GOING SATURDAY MORNING...WHERE
MODELS ARE IN GENERAL AGREEMENT DEPICTING LOW PRESSURE NEAR OMAHA
WITH A WARM...OR INITIALLY STATIONARY FRONT REACHING EAST ALONG THE
IA/MO BORDER. ALL ARE SUGGESTING A RIDGE TOPPING SHORTWAVE THAT WILL
PUSH THROUGH DURING THE DAY...WHICH SENDS THE SURFACE LOW
EAST-NORTHEAST ACROSS THE FORECAST AREA AND NUDGES THE SURFACE
BOUNDARY NORTHWARD. ON THE WARM SIDE OF THIS BOUNDARY...MODEL CAPES
ARE ROUGHLY IN THE RANGE OF 3500 TO OVER 4000 J/KG WITH BULK SHEAR
VALUES AROUND 40 TO 45 KTS...SUFFICIENT FOR SEVERE STORMS AND
SUPERCELLS ESPECIALLY ALONG THE BOUNDARY IN THE AFTERNOON INTO
EVENING. SPC HAS THE ENTIRE FORECAST AREA IN A SLIGHT RISK FOR DAY
2. MUCH WILL DEPEND ON THE TIMING OF THE EXITING OR DISSIPATING
OVERNIGHT MCS AND RELATED BOUNDARIES AND CLOUD COVER. FOR NOW...WILL
CONTINUE A BROAD-BRUSH APPROACH WITH LIKELY POPS FOR THUNDERSTORMS
OVER THE ENTIRE AREA. HIGHS WILL LIKELY BE LIMITED TO THE UPPER 70S
ACROSS THE NORTH...WHILE THE SOUTH SHOULD AT LEAST PUSH INTO THE 80S
WITH DEWPOINTS INTO THE 70S...DEPENDING ON TRENDS WITH CLOUD COVER AND
FRONTAL TIMING. ELEVATED SW FLOW OF 15 TO 30 KTS WILL ADVECT A HIGH
PW AIRMASS...AROUND 1.5 TO 1.8 OR 150 PERCENT OF NORMAL OVER THE
ENTIRE AREA...THAT WILL SUPPORT HEAVY RAINFALL IN HP TYPE SUPERCELLS OR
WHERE STORMS TRAIN ALONG BOUNDARIES. THE RESULTING FLASH FLOODING
THREAT WILL BE HIGHLY DEPENDENT ON RAINFALL COVERAGE AND AMOUNTS
FROM THE PREVIOUS EVENT. FOR NOW...HAVE WIDESPREAD QPF AMOUNTS OF A
QUARTER TO HALF INCH...BUT FULLY EXPECT STORM SCALE TOTALS OF 1 TO 2
INCHES.
SATURDAY NIGHT...A STRONGER SHORTWAVE...INITIALLY OVER THE TX BEND
REGION AT 00Z...IS SHOWN RIDING NORTH AND THEN SWEEPING EAST ACROSS
THE FORECAST AREA IN THE FIRST HALF OF THE NIGHT...PROVIDING RENEWED
FOCUS FOR LIKELY ANOTHER MCS AND POSSIBLE HEAVY RAINFALL AND LIKELY
POPS ARE MAINTAINED. THIS SYSTEM IS EXPECTED TO SUPPRESS THE FRONTAL
BOUNDARY BACK TO JUST SOUTH OF THE FORECAST AREA SUNDAY. THE CLOSE
PROXIMITY OF THIS BOUNDARY...AND A STRONG UPPER SHORTWAVE THEN
ADVANCING FROM THE NW WILL KEEP SHOWERS AND THUNDERSTORMS IN THE
FORECAST THROUGH MONDAY...BUT THE HEAVY RAINFALL THREAT WILL BE
DIMINISHED. A NW FLOW AND HIGH PRESSURE THEN SUGGESTS DRY CONDITIONS
THROUGH AT LEAST WED WITH NEAR TO SLIGHTLY BELOW NORMAL
TEMPERATURES. MODEL CONSENSUS HAS CHANCES FOR SHOWERS AND
THUNDERSTORMS RETURNING TO THE FORECAST THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 642 AM CDT FRI JUN 14 2013
CONVECTION IN CENTRAL IOWA WILL DISSIPATE THROUGH 18Z/14 AS IT
ENCOUNTERS DRIER AIR OVER EASTERN IOWA. VFR WX IS EXPECTED
THROUGH 00Z/15. TSRA WILL DEVELOP AFT 20Z/14 THAT WILL BECOME MORE
NUMEROUS ACROSS EASTERN IOWA/NORTHERN ILLINOIS AFT 00Z/15. AFT
00Z/15 VFR WX IS EXPECTED TO CONTINUE. HOWEVER...THE TSRA ARE
EXPECTED TO EVOLVE INTO A TSRA COMPLEX THAT MAY RESULT IN MVFR
CONDITIONS AFT 06Z/15. ..08..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...HAASE
SYNOPSIS...08
SHORT TERM...08
LONG TERM...SHEETS
AVIATION...08
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
656 AM CDT FRI JUN 14 2013
.UPDATE...
ISSUED AT 642 AM CDT FRI JUN 14 2013
RADAR SHOWS THE CONVECTION IN CENTRAL IOWA CONTINUES BUT IS
RAPIDLY WEAKENING AS IT MOVES INTO DRIER AIR AND AWAY FROM THE
BETTER SUPPORT. RAP TRENDS CONTINUE TO SHOW A WEAK BUT RESPECTABLE
THETA E GRADIENT WHICH IS HELPING TO MAINTAIN THE CONVECTION.
BASED ON RADAR AND RAP TRENDS SOME OF THIS CONVECTION WILL GET
INTO THE WESTERN CWFA THIS MORNING AS LIGHT SHOWERS OR SPRINKLES
BEFORE DISSIPATING.
WATER VAPOR AND THE RAP SHOW TWO VORT MAXES CURRENTLY MOVING
ACROSS NEBRASKA. THESE FEATURES WILL DRIVE THE DIURNAL CONVECTION
THIS AFTERNOON THAT WILL EVENTUALLY EVOLVE INTO ANOTHER NOCTURNAL
MCS LATE TONIGHT. ..08..
&&
.SYNOPSIS...
ISSUED AT 308 AM CDT FRI JUN 14 2013
06Z SFC ANALYSIS HAS A HIGH RUNNING FROM LAKE SUPERIOR INTO THE
LOWER MISSISSIPPI VALLEY. LOWS WERE IN SOUTHEAST MONTANA AND
SOUTHEAST COLORADO. THE MAIN SYNOPTIC FRONT RAN FROM SOUTHWEST
KANSAS INTO THE DEEP SOUTH. DEW POINTS WERE IN THE 60S AND 70S FROM
THE CENTRAL PLAINS INTO THE DEEP SOUTH WITH 40S AND 50S ACROSS THE
GREAT LAKES AND UPPER MISSISSIPPI VALLEY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM CDT FRI JUN 14 2013
THE MCS AND LIFT TOOLS INDICATE THE CURRENT CONVECTION FROM
SOUTHWEST MN INTO NORTHERN IOWA IS ASSOCIATED WITH A THETA E
GRADIENT AND VORT MAX. THIS CONVECTION WILL SLOWLY DISSIPATE AS IT
MOVES AWAY FROM THE BETTER MOISTURE AND INTO THE RIDGE. THUS THE
MORNING HOURS WILL BE DRY WITH AN INCREASE IN CLOUD COVER.
HOWEVER...THE CLOUD COVER WILL SLOWLY THIN AS IT HITS THE RIDGE SO
THERE SHOULD BE A RESPECTABLE AMOUNT OF SUNSHINE TO HELP WARM UP.
RAP TRENDS ALONG WITH THE MCS AND LIFT TOOLS INDICATE THE VORT MAX
MOVING THROUGH SOUTHERN NEBRASKA WILL PROBABLY BE THE MECHANISM TO
GENERATE DIURNAL CONVECTION THIS AFTERNOON. THIS CONVECTION SHOULD
DEVELOP OR MOVE INTO THE WESTERN CWFA AROUND MID AFTERNOON AND
SLOWLY OVERSPREAD THE WESTERN HALF OF THE CWFA THROUGH LATE
AFTERNOON.
TONIGHT...THE MCS AND LIFT TOOLS INDICATE THE DIURNAL CONVECTION IS
EXPECTED TO EVOLVE INTO ANOTHER NOCTURNAL MCS ACROSS THE AREA.
CONVECTION SHOULD REMAIN ISOLATED TO SCATTERED UNTIL CLOSER TO
MIDNIGHT WHEN THE LLJ VEERS INTO THE CWFA. AT THIS TIME UPSCALE
GROWTH AND AN INCREASE IN AREAL COVERAGE ACROSS THE CWFA WILL BE
SEEN. PWATS ARE EXPECTED TO BE OVER 1.5 INCHES SO THERE WOULD BE A
THREAT OF HEAVY RAIN IF STORMS MOVE OVER THE SAME AREA. THE GROUND
IS REASONABLY DRY SO THIS INITIAL ROUND OF RAIN SHOULD NOT CAUSE
MUCH IN THE WAY OF PROBLEMS. ..08..
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 308 AM CDT FRI JUN 14 2013
INITIAL FOCUS IS ON THUNDERSTORM POTENTIAL FOR SATURDAY THAT WILL
HAVE A RISK FOR BOTH SEVERE STORMS AND HEAVY RAINFALL. TRANSITION TO
NW FLOW TO THEN BRING COOLER AND DRIER WEATHER FOR AT LEAST THE
FIRST HALF OF NEXT WEEK.
NOCTURNAL MCS WILL LIKELY BE ON-GOING SATURDAY MORNING...WHERE
MODELS ARE IN GENERAL AGREEMENT DEPICTING LOW PRESSURE NEAR OMAHA
WITH A WARM...OR INITIALLY STATIONARY FRONT REACHING EAST ALONG THE
IA/MO BORDER. ALL ARE SUGGESTING A RIDGE TOPPING SHORTWAVE THAT WILL
PUSH THROUGH DURING THE DAY...WHICH SENDS THE SURFACE LOW
EAST-NORTHEAST ACROSS THE FORECAST AREA AND NUDGES THE SURFACE
BOUNDARY NORTHWARD. ON THE WARM SIDE OF THIS BOUNDARY...MODEL CAPES
ARE ROUGHLY IN THE RANGE OF 3500 TO OVER 4000 J/KG WITH BULK SHEAR
VALUES AROUND 40 TO 45 KTS...SUFFICIENT FOR SEVERE STORMS AND
SUPERCELLS ESPECIALLY ALONG THE BOUNDARY IN THE AFTERNOON INTO
EVENING. SPC HAS THE ENTIRE FORECAST AREA IN A SLIGHT RISK FOR DAY
2. MUCH WILL DEPEND ON THE TIMING OF THE EXITING OR DISSIPATING
OVERNIGHT MCS AND RELATED BOUNDARIES AND CLOUD COVER. FOR NOW...WILL
CONTINUE A BROAD-BRUSH APPROACH WITH LIKELY POPS FOR THUNDERSTORMS
OVER THE ENTIRE AREA. HIGHS WILL LIKELY BE LIMITED TO THE UPPER 70S
ACROSS THE NORTH...WHILE THE SOUTH SHOULD AT LEAST PUSH INTO THE 80S
WITH DEWPOINTS INTO THE 70S...DEPENDING ON TRENDS WITH CLOUD COVER AND
FRONTAL TIMING. ELEVATED SW FLOW OF 15 TO 30 KTS WILL ADVECT A HIGH
PW AIRMASS...AROUND 1.5 TO 1.8 OR 150 PERCENT OF NORMAL OVER THE
ENTIRE AREA...THAT WILL SUPPORT HEAVY RAINFALL IN HP TYPE SUPERCELLS OR
WHERE STORMS TRAIN ALONG BOUNDARIES. THE RESULTING FLASH FLOODING
THREAT WILL BE HIGHLY DEPENDENT ON RAINFALL COVERAGE AND AMOUNTS
FROM THE PREVIOUS EVENT. FOR NOW...HAVE WIDESPREAD QPF AMOUNTS OF A
QUARTER TO HALF INCH...BUT FULLY EXPECT STORM SCALE TOTALS OF 1 TO 2
INCHES.
SATURDAY NIGHT...A STRONGER SHORTWAVE...INITIALLY OVER THE TX BEND
REGION AT 00Z...IS SHOWN RIDING NORTH AND THEN SWEEPING EAST ACROSS
THE FORECAST AREA IN THE FIRST HALF OF THE NIGHT...PROVIDING RENEWED
FOCUS FOR LIKELY ANOTHER MCS AND POSSIBLE HEAVY RAINFALL AND LIKELY
POPS ARE MAINTAINED. THIS SYSTEM IS EXPECTED TO SUPPRESS THE FRONTAL
BOUNDARY BACK TO JUST SOUTH OF THE FORECAST AREA SUNDAY. THE CLOSE
PROXIMITY OF THIS BOUNDARY...AND A STRONG UPPER SHORTWAVE THEN
ADVANCING FROM THE NW WILL KEEP SHOWERS AND THUNDERSTORMS IN THE
FORECAST THROUGH MONDAY...BUT THE HEAVY RAINFALL THREAT WILL BE
DIMINISHED. A NW FLOW AND HIGH PRESSURE THEN SUGGESTS DRY CONDITIONS
THROUGH AT LEAST WED WITH NEAR TO SLIGHTLY BELOW NORMAL
TEMPERATURES. MODEL CONSENSUS HAS CHANCES FOR SHOWERS AND
THUNDERSTORMS RETURNING TO THE FORECAST THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 642 AM CDT FRI JUN 14 2013
CONVECTION IN CENTRAL IOWA WILL DISSIPATE THROUGH 18Z/14 AS IT
ENCOUNTERS DRIER AIR OVER EASTERN IOWA. VFR WX IS EXPECTED
THROUGH 00Z/15. TSRA WILL DEVELOP AFT 20Z/14 THAT WILL BECOME MORE
NUMEROUS ACROSS EASTERN IOWA/NORTHERN ILLINOIS AFT 00Z/15. AFT
00Z/15 VFR WX IS EXPECTED TO CONTINUE. HOWEVER...THE TSRA ARE
EXPECTED TO EVOLVE INTO A TSRA COMPLEX THAT MAY RESULT IN MVFR
CONDITIONS AFT 06Z/15. ..08..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...08
SYNOPSIS...08
SHORT TERM...08
LONG TERM...SHEETS
AVIATION...08
AREA FORECAST DISCUSSION...UPDATED
NWS DODGE CITY KS
613 PM CDT SAT JUN 15 2013
...UPDATED FOR AVIATION...
.SYNOPSIS...
ISSUED AT 202 PM CDT SAT JUN 15 2013
THE 12Z UPPER AIR ANALYSIS SHOWED BROAD RIDGING CONTINUING OVER THE
LOWER 48 STATES. NUMEROUS WEAK SHORTWAVE TROUGHS WERE EMBEDDED IN
THE FLOW OVER THE RIDGE. A STRONGER WAVE EXTENDED FROM OVER
WESTERN KANSAS INTO THE BIG BEND AREA OF SOUTHWEST TEXAS. THIS
WAVE HAD BROUGHT SOME EARLY MORNING SHOWERS AND THUNDERSTORMS TO
WESTERN KANSAS WHICH HAVE SINCE MOVED INTO CENTRAL AND EASTERN
KANSAS BY EARLY AFTERNOON. BEHIND THIS WAVE...SUBSIDENCE WAS
SPREADING ACROSS WESTERN KANSAS AS EVIDENT IN THE WATER VAPOR IMAGERY.
TO THE WEST OF THIS...A WEAK DISTURBANCE WAS MOVING EAST THROUGH
THE CENTRAL ROCKIES. A WEAK FRONTAL BOUNDARY EXTENDED FROM EASTERN
NEBRASKA ACROSS NORTHWEST KANSAS INTO EAST CENTRAL COLORADO. LOW
LEVEL MOISTURE CONTINUES TO STREAM NORTH TOWARD THE CENTRAL PLAINS AS
DEWPOINTS IN THE LOW TO MID 60S ADVECT INTO WESTERN AND CENTRAL KANSAS.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 202 PM CDT SAT JUN 15 2013
IT APPEARS THAT PORTIONS OF WESTERN AND CENTRAL KANSAS COULD HAVE
A DECENT SHOT AT RECEIVING RAIN LATE THIS AFTERNOON INTO
TONIGHT. THE NAM AND GFS MODELS SHOW A TREND OF THUNDERSTORMS
DEVELOPING OVER EASTERN COLORADO AND MOVING INTO WESTERN KANSAS
DURING THE EVENING HOURS. THE HRRR HAS BEEN SHOWING THIS TREND AS
WELL. THE LATEST RUNS OF THAT MODEL ARE SHOWING WIDELY SCATTERED
THUNDERSTORMS DEVELOPING OVER WEST CENTRAL KANSAS LATE THIS
AFTERNOON AND MOVING INTO CENTRAL KANSAS WITH ANOTHER ROUND OF
THUNDERSTORMS THAT DEVELOP OVER EASTERN COLORADO THEN MOVING
ACROSS NORTHWEST AND WEST CENTRAL KANSAS LATER THIS EVENING. THINK
THAT THE TWO AREAS OF STORMS DEPICTED BY THE HRRR MAY BE CORRECT
GIVEN THE LOCATION OF THE FRONTAL BOUNDARY AND INCREASING
INSTABILITY. THE SUBSIDENCE CURRENTLY OVER THE REGION MAY QUASH
ANY LATE AFTERNOON CONVECTION BUT MODEL SOUNDINGS SHOW THE AREA
BECOMING UNCAPPED BY 00Z SO CAN`T TOTALLY RULE OUT A STORM OR TWO.
LATER TONIGHT AM EXPECTING THUNDERSTORMS TO MOVE OUT INTO WEST
CENTRAL AND PARTS OF SOUTHWEST KANSAS. HAVE INCREASED
PRECIPITATION CHANCES TO 50-55 PERCENT ESPECIALLY IN THE AREA
NORTH OF A LINE FROM SYRACUSE THROUGH MONTEZUMA, DODGE CITY AND
LARNED BASED OFF OF TRENDS IN THE HRRR. THE MODELS HINT AT A LOW
LEVEL JET DEVELOPING TONIGHT WHICH COULD HELP SUSTAIN THINGS INTO
THE LATE NIGHT HOURS BUT THINK WE WILL SEE A DECREASING TREND
AFTER 06Z.
SUNDAY SHOULD STAR OUT PARTLY TO MOSTLY SUNNY. ANOTHER WEAK
SHORTWAVE IS PROGGED TO MOVE OUT OF THE ROCKIES DURING THE LATE
AFTERNOON HOURS. HARD TO TELL WHERE EXACTLY THUNDERSTORMS WILL
INITIATE GIVEN THE UNCERTAINTY OF THE FRONTAL POSITION AND THE
POTENTIAL FOR ANY LEFTOVER OUTFLOW BOUNDARIES. WILL CONTINUE THE
PREVIOUS FORECAST TREND OF INCREASING POPS INTO THE CHANCE
CATEGORY BY LATE AFTERNOON. HIGH TEMPERATURES ON SUNDAY MAY ALSO
BE A LITTLE PROBLEMATIC DEPENDING ON HOW MUCH AND WHERE RAINFALL
OCCURS TONIGHT. WILL KEEP HIGHS IN THE UPPER 80S TO NEAR 90 IN
MOST AREAS WITH SOME LOW 90S OUT ALONG THE COLORADO BORDER.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 333 PM CDT SAT JUN 15 2013
FOR THE LATE SUNDAY THROUGH EARLY WEDNESDAY PERIOD, A FLAT UPPER
LEVEL RIDGE WILL BE SITUATED OVER THE SOUTHERN AND CENTRAL ROCKIES, WITH
WEST-NORTHWESTERLY CROSS-MOUNTAIN, MID LEVEL, FLOW ACROSS THE HIGH
PLAINS. THIS PATTERN WILL LEAD TO WEAK MID LEVEL CAPPING AND SURFACE
LEE TROUGHING, ALONG WITH LOW LEVEL MOISTURE RETURN ON THE HIGH
PLAINS. IN ADDITION, THE SOUTHERN BRANCH OF THE WESTERLIES AT MID
AND HIGH LEVELS WILL BE SITUATED FROM THE SOUTHWESTERN UNITED
STATES ACROSS THE CENTRAL PLAINS. ALL THESE FACTORS ARE FAVORABLE
FOR NOCTURNAL STORM CLUSTERS TO DEVELOP THIS TIME OF YEAR ON THE FRONT
RANGE AND HIGH PLAINS EVERY EVENING AND NIGHTTIME. THEREFORE,
CHANCES OF THUNDERSTORMS WITH BENEFICIAL RAINS LOOK HIGH. BUT THE
EXACT PLACEMENT OF THE RAIN AREAS IS NOT KNOWN WITH HIGH
CONFIDENCE. LOTS OF COOL OUTFLOW FROM THE THUNDERSTORM CLUSTERS
WILL LEAD TO COOLER HIGH TEMPERATURES EACH DAY THROUGH TUESDAY.
THE BEST CHANCES FOR RAIN APPEAR TO BE SUNDAY AND MONDAY NIGHTS AS
MUCH MORE STABLE AIR COULD BE IN PLACE BY TUESDAY.
FOR THE WEDNESDAY TO FRIDAY PERIOD, UPPER LEVEL RIDGING IS EXPECTED
TO REDEVELOP ACROSS EASTERN KANSAS, MISSOURI AND OKLAHOMA, WITH
UPPER LEVEL TROUGHING OVER THE NORTHERN ROCKIES. THIS WILL LEAD TO
MUCH DRIER WEATHER AND WARMER TEMPERATURES, WITH HIGHS APPROACHING
100F BY FRIDAY AND SATURDAY. ISOLATED THUNDERSTORMS CANNOT BE RULED
OUT EACH AFTERNOON AND EVENING ALONG THE SOUTHERN EDGE OF THE WESTERLIES
NEAR THE LEE TROUGH IN WESTERN KANSAS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 606 PM CDT SAT JUN 15 2013
SOUTHEASTERLY UPSLOPE FLOW WILL CONTINUE TONIGHT AT 10-15KT. AN MCS
IS FORECAST TO MOVE FROM EASTERN COLORADO AND INTO WESTERN KANSAS
LATE THIS EVENING. THUNDERSTORMS ARE EXPECTED IN THE KGCK AREA
FROM 03-08Z, AND IN KDDC AND KHYS FROM 05-08Z. THE MAIN THREAT
WILL BE OUTFLOW WINDS TO 40-50KT AND SOME SMALL HAIL TO DIME SIZE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 67 89 64 86 / 50 40 60 30
GCK 66 89 64 86 / 50 40 50 20
EHA 66 92 64 87 / 30 20 40 20
LBL 67 91 64 86 / 30 30 50 30
HYS 66 87 64 85 / 50 50 60 20
P28 69 91 68 88 / 30 40 80 60
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...GERARD
SHORT TERM...GERARD
LONG TERM...FINCH
AVIATION...KRUSE
AREA FORECAST DISCUSSION
NWS CARIBOU ME
554 PM EDT FRI JUN 14 2013
.SYNOPSIS...
A WEAK COLD FRONT WILL CROSS THE AREA LATE THIS AFTERNOON AND EARLY
EVENING. A SECONDARY COLD FRONT WILL APPROACH FROM QUEBEC SATURDAY
AND CROSS THE REGION SATURDAY NIGHT. WEAK LOW PRESSURE FROM THE
GREAT LAKES WILL APPROACH FROM THE WEST LATER SUNDAY.
&&
.NEAR TERM /THROUGH SATURDAY/...
550 PM UPDATE: INCLUDED GUSTY WINDS AND SMALL HAIL AS FAR SOUTH AS
NORTHERN WASHINGTON COUNTY THROUGH 00Z AS RADAR INDICATING SOME OF THE
STORMS HAVE SOME HAIL W/REFLECTIVITY CORE ABOVE THE FREEZING LEVEL
OF 8500 FT. THIS MATCHES WELL W/THE LATEST LAPS AND RUC ANALYSIS
W/INSTABILITY AXIS SHIFTING FURTHER SOUTH.
PREVIOUS DISCUSSION:
LATEST RADAR REF SHOWS THE MOST IMPRESSIVE CNVCTV ACTIVITY OVR NE
ME AT THE MOMENT...BUT EVEN SO...TOPS HAVE GENERALLY NOT EXCEEDED
25 KFT FOR THE MOST PART. FCST SBCAPES INTO ERLY EVE WILL BE IN
THE 300 TO 600 J/KG RANGE...ENOUGH FOR GENERAL THUNDER...WITH
ISOLD SVR TSTMS SLIMLY POSSIBLE. THINKING IS THAT ACTIVITY NOW
SLIDING S (WITH FORWARD CORFIDI PROPAGATION OF 15 KT OR SO) TOWARD
CNTRL PTNS OF THE FA WILL STABILIZE SOMEWHAT DUE TO MID/HI CLD CVR
HANGING ON OVR THIS AND DOWNEAST AREAS FOR MUCH OF THE DAY.
THE CAPE ENVIRONMENT WILL CONTINUE FOR AREAS OF THE N NOT BEING
RAN OVR BY CURRENT CNVCTN UNTIL ERLY EVE...AFTERWHICH THE LOSS OF
HTG AND THE BUCKLING OF WEAK LLVL THETA-E RIDGE ACROSS THE N WILL
RESULT IN DISSIPATION OF ACTIVITY BY MID TO LATE EVE.
FOLLOWING THE UPPER LVL S/WV CROSSING THE FA FROM QB...LLVL COOL
ADVCN WILL BRING DRIER SFC DWPTS AND CLRG TO THE REGION LATE TNGT
AND ERLY SAT MORN. SAT WILL BEGIN MCLR...BUT ANOTHER S/WV ASSOCIATED
WITH A STRONG BUT TIGHT MID LVL VORTEX FROM HUDSON BAY TRACKING
ESE N OF THE FA INTO THE CAN MARITIMES WILL BRING SOME CLDNSS TO
THE FA BY AFTN AND PERHAPS ANOTHER CHC OF SHWRS AHEAD OF A
SECONDARY COLD FRONT SLATED TO ARRIVE INTO NW PTNS OF THE FA BY
SAT EVE. NW WIND GUSTS COULD REACH 25 TO 30 MPH MIDDAY AND AFTN
SAT DUE TO A STRONGER PRES GRAD AT THE SFC AND WINDS ALF.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
ANY SHOWERS THAT DEVELOP ON SATURDAY WILL QUICKLY SUBSIDE DURING THE
EVENING HOURS AS DAYTIME HEATING IS LOST. A WEAK SECONDARY FRONT
WILL TRAVERSE ACROSS THE REGION OVERNIGHT SATURDAY NIGHT, USHERING
IN MUCH DRIER AIR. AS SUCH, SATURDAY NIGHT WILL BE DRY AND COOL
UNDER PARTLY TO MOSTLY CLEAR SKIES. HOWEVER, RAIN RETURNS BY SUNDAY
AFTERNOON AS A WARM FRONT SLOWLY LIFTS TOWARD NORTHERN NEW ENGLAND.
THIS FRONT WILL CROSS THE PINE TREE STATE SUNDAY NIGHT AND STALL
SOMEWHERE OVER SOUTHERN QUEBEC/NORTHERN MAINE. ALTHOUGH THERE MAY BE
A BRIEF BREAK FROM THE RAIN SUNDAY NIGHT, IT RETURNS MONDAY AS A
WAVE OF LOW PRESSURE TRAVELS ALONG THE STALLED BOUNDARY. GIVEN THE
UNCERTAINTY ON EXACTLY HOW JUST HOW FAR NORTH THE WARM FRONT WILL
LIFT, IT IS HARD TO SAY HOW MUCH OF THE FORECAST AREA WILL BE IN THE
WARM SECTOR COME MONDAY. FOR THOSE AREAS THAT ARE ON THE SOUTHERN
SIDE OF THE FRONT, THUNDERSTORMS WILL BE POSSIBLE (AWAY FROM THE
COAST) AND TEMPERATURES WILL REACH INTO THE 70S. NORTH OF THE FRONT,
TEMPERATURES WILL REMAIN IN THE 60S AND THE PRECIPITATION WILL BE
MORE STRATIFORM IN NATURE WITH LIMITED INSTABILITY. CURRENT MODEL
GUIDANCE IS SPLIT ON THE FRONT`S POSITION (QUEBEC VS MAINE), SO HAVE
STAYED PRETTY CLOSE TO THE PREVIOUS FORECAST (WHICH LOOKED
REASONABLE) FOR CONSISTENCY. ALSO OPTED TO LEAVE ANY MENTION OF
THUNDER OUT OF THE FORECAST FOR NOW GIVEN THE UNCERTAINTY.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
GUIDANCE IN REASONABLE AGREEMENT WITH TROUGH LOCATION ACROSS THE
GREAT LAKES. THE MAJOR DIFFERENCE RIGHT NOW IS THE TIMING. THE
00/06Z GFS BRINGS A SURFACE LOW TO THE NORTH WITH FRONTAL BOUNDARY
EXTENDING SOUTH FOR TUESDAY AFTERNOON. THE 00Z ECMWF BRINGS THE
SURFACE LOW SOUTH WITH A SHORTWAVE RIDING THROUGH THE LARGER UPPER
LEVEL LOW BUT IS A BIT SLOWER WITH TIMING. EITHER SCENARIO WOULD
BRING DECENT SHOT OF PRECIP ACROSS THE REGION FOR TUESDAY AND
TUESDAY NIGHT. THE LATEST 12Z GFS STILL HAS SAME TIMING WITH
INTIAL LOW. THE BIGGEST CHANGE WOULD BE THE DEVELOPMENT OF A
COASTAL LOW FOR WEDNESDAY IN RESPONSE TO ANOTHER SHORTWAVE THAT
DEVELOPS NEAR THE GREAT LAKES. THE 00Z CMC DOES INTRODUCE THE
SURFACE LOW WEDNESDAY BUT MUCH FURTHER SOUTH THAN THE 12Z GFS.
CONDITIONS DO IMPROVE LATER IN THE FORECAST PERIOD AS HIGH
PRESSURE MOVES EAST. TEMPERATURES THROUGH THE PERIOD STAYING NEAR
NORMAL.
&&
.AVIATION /22Z FRIDAY THROUGH WEDNESDAY/...
NEAR TERM: VFR XPCTD ALL SITES THRU SAT...XCPT BRIEFLY MVFR IN HVY
RNFL LATE THIS AFTN AND EVE IN ANY TSTM OR HEAVIER SHWR.
SHORT TERM: VFR CONDITIONS ARE EXPECTED SATURDAY NIGHT INTO
SUNDAY MORNING, BUT MVFR CEILINGS WILL BE POSSIBLE SUNDAY
AFTERNOON THROUGH MONDAY AS RAIN SHOWERS SPREAD INTO THE REGION.
ISOLATED THUNDERSTORMS WILL BE POSSIBLE MONDAY AFTERNOON, MAINLY
AT KBHB AND KBGR. MVFR/VFR CONDITIONS AND UNSETTLED WEATHER WILL
CONTINUE INTO MID WEEK.
&&
.MARINE...
NEAR TERM: NO HDLNS ANTICIPATED ATTM. THE ONLY CONCERN IS SWELL
COMING BACK BACK AROUND THE W END OF NOVA SCOTIA BY SAT AS THE
DEPARTING LOW MOVES INTO THE OPEN N ATLC. USED WW3 WITH SWAN NAM
SMOOTHED NEAR THE COASTLINE TO REDUCE COASTLINE WV HTS TO AROUND
1 TO 2 FT.
SHORT TERM: A WEAK FRONT WILL PASS ACROSS THE WATERS SATURDAY NIGHT,
WITH ANOTHER TO COME LATE SUNDAY. THIS WILL KEEP UNSETTLED WEATHER
AROUND INTO EARLY NEXT WEEK. HOWEVER, CONDITIONS ARE EXPECTED TO
REMAIN BELOW SMALL CRAFT CRITERIA, SO NO HEADLINES ARE ANTICIPATED.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HEWITT/VJN
SHORT TERM...HASTINGS
LONG TERM...JORDAN
AVIATION...HEWITT/VJN/HASTINGS
MARINE...HEWITT/VJN/HASTINGS
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
842 PM MDT SAT JUN 15 2013
.UPDATE...
A WEAK COOL FRONT IS MOVING SOUTH ACROSS THE AREA THIS EVENING AND
CAN BE SEEN ON RADAR AS A FINE-LINE IN BASE REFLECTIVITY IMAGES TO
THE NORTHEAST OF BILLINGS AT 0230 UTC. WINDS WILL BECOME NORTHERLY
BEHIND THE FRONT...BUT THE SURFACE GRADIENT IS WEAK ENOUGH THAT IT
MAY BE DIFFICULT TO PICK OUT THE EFFECTS OF THE FRONT AFTER 06 UTC
WHEN SOME LIGHT DRAINAGE EFFECTS TAKE OVER WINDS IN SOME SPOTS. WE
DID BLEND THE GRIDDED WIND FORECASTS TO RECENT LAMP AND RUC OUTPUT
TO HELP CAPTURE THIS SCENARIO. OTHERWISE...WE LOWERED TEMPERATURES
JUST SLIGHTLY IN A FEW PLACES...ESPECIALLY AROUND LIVINGSTON WHERE
EVENING DEWPOINTS ARE RUNNING IN THE MID 30S F. SCHULTZ
&&
.SHORT TERM...VALID FOR SUN AND MON...
A SUNNY TO MOSTLY SUNNY WEEKEND REMAINS ON TAP ACROSS OUR
FORECAST AREA ALONG WITH SEASONAL TEMPERATURES. UPPER LOW
CONTINUES TO SLOWLY MOVE EAST AND SOUTHEAST ACROSS SOUTHERN CANADA
INTO NORTH DAKOTA AND MINNESOTA LEAVING MOSTLY CLEAR SKIES FOR OUR
AREA. SUBSIDENCE ACROSS SOUTHERN MONTANA IS RESULTING IN A MOSTLY
SUNNY DAY BUT COLD AIR ALOFT COMBINED WITH A WEAK COLD FRONT
ACROSS THE NORTHEASTERN PORTIONS OF THE STATE HAS RESULTED IN
QUITE A BIT OF CUMULUS ACROSS THAT AREA. THIS FRONT WILL SLIDE
SOUTH THIS EVENING AND OVERNIGHT BRINGING A WIND SHIFT TO THE
NORTHEAST LATE TONIGHT AND THROUGH THE DAY SUNDAY.
HOWEVER...ATMOSPHERE REMAINS DRY SO NOT EXPECTING ANY PRECIP WITH
THE FRONT. A FEW CLOUDS WILL POSSIBLY WORK THEIR WAY SOUTH INTO
OUR FAR NORTH AND NORTHEAST ZONES BUT THESE ARE EXPECTED TO
DISSIPATE SHORTLY AFTER SUNSET. TEMPERATURES WILL BE A FEW DEGREES
WARMER TONIGHT FOR SOME AREAS BUT STILL EXPECT A CHILLY NIGHT ONCE
AGAIN WITH TEMPERATURES SLIGHTLY BELOW NORMAL.
HIGH PRESSURE RIDGING BEGINS TO BUILD ALONG WITH RISING HEIGHTS
SUNDAY AND ESPECIALLY INTO MONDAY. A FEW WEAK DISTURBANCES MAY
UNDERCUT THE RIDGE RESULTING IN A SLIGHT SHOWER/THUNDERSTORM
CHANCE MAINLY OVER THE MOUNTAINS AND NEARBY FOOTHILLS BOTH SUNDAY
AND MONDAY AFTERNOON/EVENING. HIGH TEMPERATURES SUNDAY WILL BE
AROUND AVERAGE WITH MIDDLE TO UPPER 70S WITH READINGS A FEW
DEGREES WARMER ON MONDAY. HOOLEY
.LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT...
RIDGING BEGINS BREAKING DOWN LATE TUES AS UPPER LEVEL FLOW BECOMES
INCREASINGLY SOUTHWESTERLY. SHORTWAVES EMBEDDED WITHIN THE FLOW
WILL WORK WITH SURFACE DEWPOINTS IN THE 40S TO LOW 50S...A BIT OF
SHEAR...AND DAYTIME INSTABILITY TO INCREASE CHANCES OF SHOWERS
AND THUNDERSTORMS ACROSS WESTERN AND CENTRAL AREAS...AS FAR EAST
AS BILLINGS AND SHERIDAN. FOR NOW...KEPT POPS LOW THROUGH TUES
EVE...BUT IF SHORTWAVE ACTIVITY LOOKS STRONGER AS TUES
APPROACHES...WE WILL NEED TO RAISE POPS. HIGH TEMPS WILL BE IN THE
80S.
MORE SHORTWAVE ACTIVITY IN SW FLOW ALOFT IS EXPECTED TO BRING
SHOWERS AND THUNDERSTORMS TO THE REGION WED...WITH THE BEST
CHANCES AGAIN ACROSS THE WEST AND CENTRAL WHERE STRONG UPPER LEVEL
JET ENERGY/DIVERGENCE WILL HELP TO DEEPEN A SURFACE
LOW AND INCREASE FRONTOGENETICAL AND LOW-LEVEL FORCING. SHEAR
LOOKS MARGINAL...BUT CAPE VALUES ARE QUITE HIGH WED AFTN/EVE...SO
NOT SURE ABOUT THE LIKELIHOOD OF SEVERE STORMS...BUT CERTAINLY
SOME STRONG STORMS ARE POSSIBLE. 700 MB TEMPS ACROSS THE EAST WED
AFTN/EVE WILL BE IN THE +12C TO +14C RANGE...WHICH MAY CAP THAT
REGION. SO...AT THIS POINT...LESS CONVECTIVE ACTIVITY IS EXPECTED
ACROSS THE EAST. WED NIGHT INTO THURS...THE SURFACE LOW MOVES
E...DRAGGING A COLD FRONT WITH IT. THIS WILL STABILIZE THE
ATMOSPHERE A BIT THROUGH A GOOD PORTION OF THURS. EXPECT HIGHS
AGAIN IN THE 80S ACROSS MUCH OF THE REGION WED...WITH HIGHS IN THE
70S THURS.
SHORTWAVE ENERGY ROUNDING THE BASE OF THE UPPER LEVEL TROUGH LATE
THURS INTO EARLY FRI WILL INCREASE UPPER LEVEL DIVERGENCE AND
POTENTIALLY HELP TO DEVELOP ANOTHER SURFACE LOW ACROSS SOUTHERN
MT/NORTHERN WY...SETTING THE STAGE FOR FURTHER CONVECTIVE
DEVELOPMENT ACROSS THE REGION. CONVECTION SHOULD FIRE OVER THE
WEST AND CENTRAL LATE THURS EVE...AND PROPAGATE EASTWARD THROUGH
THE OVERNIGHT HOURS AND INTO EARLY FRI AS THE LOW DRAGS ANOTHER
COLD FRONT THROUGH THE REGION. SHEAR VALUES LOOK SUFFICIENT FOR AT
LEAST STRONG STORMS LATE THURS INTO EARLY FRI MORNING...BUT LOW
LEVEL MOISTURE IS LOWER THAN WED...THUS CAPE VALUES ARE NOT ALL
THAT HIGH. WILL HAVE TO KEEP AN EYE ON SURFACE DEWPOINTS. IF THEY
RECOVER INTO THE 50S ACROSS THE EASTERN HALF OF THE REGION THURS
NIGHT...AS SUGGESTED BY THE ECMWF...THERE WILL BE A BETTER CHANCE
OF SOME STORMS BECOMING SEVERE.
FRI LOOKS TO BE A TOUCH COOLER THAN THURS ACROSS THE REGION
BEHIND THE FRONT WITH A MORE STABLE AIRMASS BUILDING
IN...ESPECIALLY BY LATER IN THE DAY. ANOTHER STRONG SHORTWAVE
TROUGH APPROACHES THE REGION SAT...INCREASING THE POTENTIAL FOR
SHOWERS AND THUNDERSTORMS. STC
&&
.AVIATION...
VFR CONDITIONS WITH NO FLIGHT HAZARDS TO AVIATION ARE EXPECTED
TONIGHT THROUGH MID DAY SUNDAY. A WEAK DISTURBANCE WILL BRING A
FEW THUNDERSTORMS OVER THE WESTERN MOUNTAINS BY MID AFTERNOON
SUNDAY. THE SHOWERS AND THUNDERSTORMS COULD CREATE A BRIEF PERIOD
OF MOUNTAIN OBSCURATIONS. THE PLAINS WILL REMAIN DRY. RICHMOND
&&
.PRELIMINARY POINT TEMP/POPS...
SUN MON TUE WED THU FRI SAT
-----------------------------------------------------------
BIL 049/077 053/080 057/085 054/086 054/075 049/074 050/073
00/U 11/B 12/T 23/T 32/T 33/T 22/T
LVM 037/078 044/081 047/084 048/083 047/070 039/071 042/072
01/U 11/B 22/T 23/T 33/T 22/T 23/T
HDN 048/079 051/080 056/088 054/090 056/076 052/075 050/074
00/U 01/U 12/T 22/T 22/T 33/T 22/T
MLS 051/078 052/079 057/086 058/087 060/079 054/075 055/075
01/U 01/U 11/U 12/T 33/T 33/T 23/T
4BQ 048/079 051/079 055/087 056/089 059/079 054/076 052/075
01/U 11/U 12/T 22/T 22/T 33/T 22/T
BHK 047/075 048/075 055/083 057/082 060/078 053/076 053/072
01/U 11/U 11/U 12/T 22/T 33/T 33/T
SHR 044/077 049/079 053/085 051/087 053/076 049/074 048/073
01/U 12/T 23/T 22/T 22/T 22/T 22/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
1128 AM MDT Fri Jun 14 2013
.UPDATE...
Current satellite imagery shows upper level trof extending from
northern Alberta to southern Idaho with the trof axis slightly east
of the Rocky Mtn Front. Moisture plume along/behind the trof axis
will bring one more round of showers and isolated to scattered
thunderstorms over central and southwest MT this aftn. Have slightly
increased chances of precipitation from Great Falls north to US/Can
border for today as morning model runs indicating enough lift and
instability there to promote better precip coverage. Although
severe storms are not expected for our region, will be keeping a
close eye on storm development as cooling aloft may bring slightly
higher chance for some storms to produce small hail. Gradual
clearing still expected this evening with dry/warmer conditions
beginning tomorrow.
Waranauskas
&&
.DISCUSSION...
Today through Sunday night...One more day of unsettled weather is in
store for the area. An upper level trof will move across the area
today bringing additional instability. A jet max rounding the upper
trof will aid in the development of showers and thunderstorms over
southwest Montana this morning. Both the models and HRRR analysis
indicate the development of storms over the southwest mountains this
morning and their subsequent movement north and east during the
afternoon. SPC has the entire county warning area under a general
thunderstorm outlook for today. Some storms may be strong but
widespread severe storms are not anticipated. Breezy westerly winds
will develop across the plains by late morning. Cooler air has moved
into southwest Montana and some snow is possible above 7500 feet
today. Convective activity ends by late afternoon with rising
heights as an upper ridge begins to build over western Montana.
Saturday and Sunday will be dry with warming temperatures. Afternoon
readings will be below seasonal averages today but warm to near to
slightly above seasonal averages this weekend. Emanuel
Sunday night through Friday...Models continue to be in good
agreement, but the overall progression of next week`s low pressure
system from the Pacific Ocean is about 24 hours slower than the
previous runs. Will address the changes below. An upper level ridge
of high pressure will linger over Montana through Monday night. The
airmass will warm to between 5 and 10 degrees above seasonal
averages, but weak steering winds aloft will keep the threat for
isolated thunderstorm activity over the higher terrain. The
aforementioned weather system will then deepen and move onto the
Pacific coast on Tuesday. The increasingly moist and unstable
southwesterly flow aloft ahead of the system will bring an
increasing chance of showers and thunderstorms mainly to the western
half of Montana. The flow aloft will also pump warmer air into the
area, causing temperatures to warm to between 10 and 15 degrees
above normal. As the system moves into the Pacific Northwest on
Wednesday, the flow aloft will become more southerly, unstable, and
diffluent. This, in turn, will bring a much better chance for
showers and thunderstorms to the area, especially over north
central/central Montana. Forecast CAPE values increase to between
1000 and 2000 J/kg Wednesday afternoon/evening, which hints at the
potential for a round of strong to possibly severe thunderstorms.
Would like to see run-to-run consistency with this feature before
mentioning severe potential in Hazardous Weather Outlook. Forecast
models differ with exact movement of this system beyond Wednesday.
GFS model moves the system into southern Alberta and Saskatchewan by
Friday, while the ECMWF model keeps the system over the Pacific
Northwest. The GEM is slow with movement of the system (moving it
over Montana), but it weakens the system. With this discrepancy,
have kept the chance for showers/thunderstorms near climatology and
will look to refine the details when the models come into better
agreement. Regardless, the models all bring a cold front through the
area Wednesday night, which should cool temperatures back to between
5 and 10 degrees below normal for Thursday through Friday and bring
breezy westerly winds to the area. Coulston
&&
.AVIATION...
Updated 1727Z.
An upper level low pressure trof will move east of the region and
high pressure will begin to build aloft. However, the airmass will
remain slightly unsettled through the afternoon and early evening.
Scattered showers and thunderstorms will develop although small hail
and strong, gusty winds are possible from thunderstorms. Westerly
surface winds will remain gusty through the afternoon and early
evening, as well. VFR conditions will prevail through the next 24
hours.
&&
.HYDROLOGY...
Point flood warnings remain in effect for the Big Sandy Creek near
Havre and Clear Creek near Chinook. Rain from recent thunderstorms
will keep water levels high in many creeks and streams. Drier
weather this weekend should result in gradually decreasing levels
into early next week.
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 64 42 75 44 / 20 10 0 0
CTB 63 42 73 43 / 20 10 0 10
HLN 64 43 75 46 / 40 10 0 0
BZN 61 38 75 41 / 70 20 0 0
WEY 55 31 68 34 / 40 10 0 0
DLN 59 36 73 41 / 70 20 0 0
HVR 68 46 76 48 / 20 20 10 10
LWT 62 41 71 44 / 30 10 0 0
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
Flood Warnings continue until further notice for Big Sandy Creek
near Havre and Clear Creek near Chinook.
&&
$$
weather.gov/greatfalls
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
930 AM MDT Fri Jun 14 2013
.UPDATE...
Current satellite imagery shows upper level trof extending from
northern Alberta to southern Idaho with the trof axis slightly east
of the Rocky Mtn Front. Moisture plume along/behind the trof axis
will bring one more round of showers and isolated to scattered
thunderstorms over central and southwest MT this aftn. Have slightly
increased chances of precipitation from Great Falls north to US/Can
border for today as morning model runs indicating enough lift and
instability there to promote better precip coverage. Although
severe storms are not expected for our region, will be keeping a
close eye on storm development as cooling aloft may bring slightly
higher chance for some storms to produce small hail. Gradual
clearing still expected this evening with dry/warmer conditions
beginning tomorrow.
Waranauskas
&&
.DISCUSSION...
Today through Sunday night...One more day of unsettled weather is in
store for the area. An upper level trof will move across the area
today bringing additional instability. A jet max rounding the upper
trof will aid in the development of showers and thunderstorms over
southwest Montana this morning. Both the models and HRRR analysis
indicate the development of storms over the southwest mountains this
morning and their subsequent movement north and east during the
afternoon. SPC has the entire county warning area under a general
thunderstorm outlook for today. Some storms may be strong but
widespread severe storms are not anticipated. Breezy westerly winds
will develop across the plains by late morning. Cooler air has moved
into southwest Montana and some snow is possible above 7500 feet
today. Convective activity ends by late afternoon with rising
heights as an upper ridge begins to build over western Montana.
Saturday and Sunday will be dry with warming temperatures. Afternoon
readings will be below seasonal averages today but warm to near to
slightly above seasonal averages this weekend. Emanuel
Sunday night through Friday...Models continue to be in good
agreement, but the overall progression of next week`s low pressure
system from the Pacific Ocean is about 24 hours slower than the
previous runs. Will address the changes below. An upper level ridge
of high pressure will linger over Montana through Monday night. The
airmass will warm to between 5 and 10 degrees above seasonal
averages, but weak steering winds aloft will keep the threat for
isolated thunderstorm activity over the higher terrain. The
aforementioned weather system will then deepen and move onto the
Pacific coast on Tuesday. The increasingly moist and unstable
southwesterly flow aloft ahead of the system will bring an
increasing chance of showers and thunderstorms mainly to the western
half of Montana. The flow aloft will also pump warmer air into the
area, causing temperatures to warm to between 10 and 15 degrees
above normal. As the system moves into the Pacific Northwest on
Wednesday, the flow aloft will become more southerly, unstable, and
diffluent. This, in turn, will bring a much better chance for
showers and thunderstorms to the area, especially over north
central/central Montana. Forecast CAPE values increase to between
1000 and 2000 J/kg Wednesday afternoon/evening, which hints at the
potential for a round of strong to possibly severe thunderstorms.
Would like to see run-to-run consistency with this feature before
mentioning severe potential in Hazardous Weather Outlook. Forecast
models differ with exact movement of this system beyond Wednesday.
GFS model moves the system into southern Alberta and Saskatchewan by
Friday, while the ECMWF model keeps the system over the Pacific
Northwest. The GEM is slow with movement of the system (moving it
over Montana), but it weakens the system. With this discrepancy,
have kept the chance for showers/thunderstorms near climatology and
will look to refine the details when the models come into better
agreement. Regardless, the models all bring a cold front through the
area Wednesday night, which should cool temperatures back to between
5 and 10 degrees below normal for Thursday through Friday and bring
breezy westerly winds to the area. Coulston
&&
.AVIATION...
Updated 1155Z.
VFR conditions are generally expected across north central, central,
and southwest Montana through at least Friday night, unless
otherwise noted. An upper level trough of low pressure will lift
northeast out of the area through the period. A disturbance within
this trough will continue rain/mountain snow showers across
southwest Montana through around 17Z, possibly causing conditions to
lower to MVFR at times at KBZN in heavier showers. Otherwise, winds
aloft will become more breezy and westerly by 18Z as the trough
moves northeast. Mid level moisture will combine with weakly
unstable airmass after 18Z. The best chance for showers and
thunderstorms will be over the mountain areas, as the westerly
downslope winds (possibly gusting over 30 kt at times) will limit
the threat over the plains. However, am thinking the likelihood that
thunderstorms will directly impact any given terminal is low, so
have not included mention of them in the TAFs. Skies will clear and
winds will decrease after 01Z as the trough exits the area.
Coulston
&&
.HYDROLOGY...
Point flood warnings remain in effect for the Big Sandy Creek near
Havre and Clear Creek near Chinook. Rain from recent thunderstorms
will keep water levels high in many creeks and streams. Drier
weather this weekend should result in gradually decreasing levels
into early next week.
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 64 42 75 44 / 20 10 0 0
CTB 63 42 73 43 / 20 10 0 10
HLN 64 43 75 46 / 40 10 0 0
BZN 61 38 75 41 / 70 20 0 0
WEY 55 31 68 34 / 40 10 0 0
DLN 59 36 73 41 / 70 20 0 0
HVR 68 46 76 48 / 20 20 10 10
LWT 62 41 71 44 / 30 10 0 0
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
Flood Warnings continue until further notice for Big Sandy Creek
near Havre and Clear Creek near Chinook.
&&
$$
weather.gov/greatfalls
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
555 AM MDT Fri Jun 14 2013
UPDATE TO AVIATION
.DISCUSSION...
Today through Sunday night...One more day of unsettled weather is in
store for the area. An upper level trof will move across the area
today bringing additional instability. A jet max rounding the upper
trof will aid in the development of showers and thunderstorms over
southwest Montana this morning. Both the models and HRRR analysis
indicate the development of storms over the southwest mountains this
morning and their subsequent movement north and east during the
afternoon. SPC has the entire county warning area under a general
thunderstorm outlook for today. Some storms may be strong but
widespread severe storms are not anticipated. Breezy westerly winds
will develop across the plains by late morning. Cooler air has moved
into southwest Montana and some snow is possible above 7500 feet
today. Convective activity ends by late afternoon with rising
heights as an upper ridge begins to build over western Montana.
Saturday and Sunday will be dry with warming temperatures. Afternoon
readings will be below seasonal averages today but warm to near to
slightly above seasonal averages this weekend. Emanuel
Sunday night through Friday...Models continue to be in good
agreement, but the overall progression of next week`s low pressure
system from the Pacific Ocean is about 24 hours slower than the
previous runs. Will address the changes below. An upper level ridge
of high pressure will linger over Montana through Monday night. The
airmass will warm to between 5 and 10 degrees above seasonal
averages, but weak steering winds aloft will keep the threat for
isolated thunderstorm activity over the higher terrain. The
aforementioned weather system will then deepen and move onto the
Pacific coast on Tuesday. The increasingly moist and unstable
southwesterly flow aloft ahead of the system will bring an
increasing chance of showers and thunderstorms mainly to the western
half of Montana. The flow aloft will also pump warmer air into the
area, causing temperatures to warm to between 10 and 15 degrees
above normal. As the system moves into the Pacific Northwest on
Wednesday, the flow aloft will become more southerly, unstable, and
diffluent. This, in turn, will bring a much better chance for
showers and thunderstorms to the area, especially over north
central/central Montana. Forecast CAPE values increase to between
1000 and 2000 J/kg Wednesday afternoon/evening, which hints at the
potential for a round of strong to possibly severe thunderstorms.
Would like to see run-to-run consistency with this feature before
mentioning severe potential in Hazardous Weather Outlook. Forecast
models differ with exact movement of this system beyond Wednesday.
GFS model moves the system into southern Alberta and Saskatchewan by
Friday, while the ECMWF model keeps the system over the Pacific
Northwest. The GEM is slow with movement of the system (moving it
over Montana), but it weakens the system. With this discrepancy,
have kept the chance for showers/thunderstorms near climatology and
will look to refine the details when the models come into better
agreement. Regardless, the models all bring a cold front through the
area Wednesday night, which should cool temperatures back to between
5 and 10 degrees below normal for Thursday through Friday and bring
breezy westerly winds to the area. Coulston
&&
.AVIATION...
Updated 1155Z.
VFR conditions are generally expected across north central, central,
and southwest Montana through at least Friday night, unless
otherwise noted. An upper level trough of low pressure will lift
northeast out of the area through the period. A disturbance within
this trough will continue rain/mountain snow showers across
southwest Montana through around 17Z, possibly causing conditions to
lower to MVFR at times at KBZN in heavier showers. Otherwise, winds
aloft will become more breezy and westerly by 18Z as the trough
moves northeast. Mid level moisture will combine with weakly
unstable airmass after 18Z. The best chance for showers and
thunderstorms will be over the mountain areas, as the westerly
downslope winds (possibly gusting over 30 kt at times) will limit
the threat over the plains. However, am thinking the likelihood that
thunderstorms will directly impact any given terminal is low, so
have not included mention of them in the TAFs. Skies will clear and
winds will decrease after 01Z as the trough exits the area.
Coulston
&&
.HYDROLOGY...
Point flood warnings remain in effect for the Big Sandy Creek near
Havre and Clear Creek near Chinook. Rain from recent thunderstorms
will keep water levels high in many creeks and streams. Drier
weather this weekend should result in gradually decreasing levels
into early next week.
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 64 42 75 44 / 20 10 0 0
CTB 63 42 73 43 / 20 10 0 10
HLN 64 43 75 46 / 40 10 0 0
BZN 61 38 75 41 / 70 20 0 0
WEY 55 31 68 34 / 40 10 0 0
DLN 59 36 73 41 / 70 20 0 0
HVR 68 46 76 48 / 20 20 10 10
LWT 62 41 71 44 / 30 10 0 0
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
Flood Warnings continue until further notice for Big Sandy Creek
near Havre and Clear Creek near Chinook.
&&
$$
weather.gov/greatfalls
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
415 AM MDT Fri Jun 14 2013
.DISCUSSION...
Today through Sunday night...One more day of unsettled weather is in
store for the area. An upper level trof will move across the area
today bringing additional instability. A jet max rounding the upper
trof will aid in the development of showers and thunderstorms over
southwest Montana this morning. Both the models and HRRR analysis
indicate the development of storms over the southwest mountains this
morning and their subsequent movement north and east during the
afternoon. SPC has the entire county warning area under a general
thunderstorm outlook for today. Some storms may be strong but
widespread severe storms are not anticipated. Breezy westerly winds
will develop across the plains by late morning. Cooler air has moved
into southwest Montana and some snow is possible above 7500 feet
today. Convective activity ends by late afternoon with rising
heights as an upper ridge begins to build over western Montana.
Saturday and Sunday will be dry with warming temperatures. Afternoon
readings will be below seasonal averages today but warm to near to
slightly above seasonal averages this weekend. Emanuel
Sunday night through Friday...Models continue to be in good
agreement, but the overall progression of next week`s low pressure
system from the Pacific Ocean is about 24 hours slower than the
previous runs. Will address the changes below. An upper level ridge
of high pressure will linger over Montana through Monday night. The
airmass will warm to between 5 and 10 degrees above seasonal
averages, but weak steering winds aloft will keep the threat for
isolated thunderstorm activity over the higher terrain. The
aforementioned weather system will then deepen and move onto the
Pacific coast on Tuesday. The increasingly moist and unstable
southwesterly flow aloft ahead of the system will bring an
increasing chance of showers and thunderstorms mainly to the western
half of Montana. The flow aloft will also pump warmer air into the
area, causing temperatures to warm to between 10 and 15 degrees
above normal. As the system moves into the Pacific Northwest on
Wednesday, the flow aloft will become more southerly, unstable, and
diffluent. This, in turn, will bring a much better chance for
showers and thunderstorms to the area, especially over north
central/central Montana. Forecast CAPE values increase to between
1000 and 2000 J/kg Wednesday afternoon/evening, which hints at the
potential for a round of strong to possibly severe thunderstorms.
Would like to see run-to-run consistency with this feature before
mentioning severe potential in Hazardous Weather Outlook. Forecast
models differ with exact movement of this system beyond Wednesday.
GFS model moves the system into southern Alberta and Saskatchewan by
Friday, while the ECMWF model keeps the system over the Pacific
Northwest. The GEM is slow with movement of the system (moving it
over Montana), but it weakens the system. With this discrepancy,
have kept the chance for showers/thunderstorms near climatology and
will look to refine the details when the models come into better
agreement. Regardless, the models all bring a cold front through the
area Wednesday night, which should cool temperatures back to between
5 and 10 degrees below normal for Thursday through Friday and bring
breezy westerly winds to the area. Coulston
&&
.AVIATION...
Updated 0430Z.
A deep trough of low pressure will continue to influence the weather
across the region tonight. Showers will push out of the area by 08Z
with conditions at KLWT and KBZN improving to VFR. Another round of
showers will affect KBZN after 10Z bringing VFR and possibly IFR
conditions through the mid-morning. Skies will begin to clear by
late morning across the area and KBZN should improve to VFR. Breezy
westerly winds will develop late morning over the plains and spread
into the valleys in the afternoon. Wind gusts will reach up to 35
knots in the plains. Expect winds to diminish Friday evening.
Langlieb
&&
.HYDROLOGY...
Point flood warnings remain in effect for the Big Sandy Creek near
Havre and Clear Creek near Chinook. Rain from recent thunderstorms
will keep water levels high in many creeks and streams. Drier
weather this weekend should result in gradually decreasing levels
into early next week.
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 64 42 75 44 / 20 10 0 0
CTB 63 42 73 43 / 20 10 0 10
HLN 64 43 75 46 / 40 10 0 0
BZN 61 38 75 41 / 70 20 0 0
WEY 55 31 68 34 / 40 10 0 0
DLN 59 36 73 41 / 70 20 0 0
HVR 68 46 76 48 / 20 20 10 10
LWT 62 41 71 44 / 30 10 0 0
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
Flood Warnings continue until further notice for Big Sandy Creek
near Havre and Clear Creek near Chinook.
&&
$$
weather.gov/greatfalls
AREA FORECAST DISCUSSION
NWS HASTINGS NE
633 PM CDT SAT JUN 15 2013
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 306 PM CDT SAT JUN 15 2013
TONIGHT THROUGH SUNDAY AFTERNOON. PRIMARY CONCERN WILL CENTER
AROUND THUNDERSTORM CHANCES. WILL NOT MAKE THIS TOO DETAILED TODAY
JUST IN CASE CONVECTION GETS GOING BY MID AFTERNOON.
CURRENT WATER VAPOR IMAGERY AND UPPER AIR DATA SHOWING CLOSED
UPPER LOW OVER SASKATCHEWAN CANADA WITH BROAD TROUGH INTO THE
NORTHERN PLAINS. THIS FEATURE GIVING THE NORTHERN PART OF OUR CWA
A LITTLE STRONGER DEEP LAYER SHEAR THAN THE SOUTHERN PART DUE TO
THE STRONGER WESTERLY FLOW. ANOTHER WEAK WAVE FROM KS TO TX HAS
HELPED DEVELOP/SUSTAIN NON SEVERE CONVECTION OVER THE SOUTHERN AND
SOUTHEAST PART OF THE CWA THIS MORNING...AND WAS JUST PUSHING TO
THE EAST OF THE AREA BY 1 PM CDT. ALSO ON THE VISIBLE SATELLITE
IMAGERY...LOOKS LIKE AN MCV OR NEDDY EDDY SWIRLING FROM THE SOUTH
CENTRAL INTO THE EASTERN PART OF THE CWA EARLY THIS AFTERNOON BUT
WOULD EXPECT ANY EFFECTS FROM THIS TO BE TO OUR EAST. DIFFICULT TO
PLACE THE SURFACE BOUNDARY EARLY THIS AFTERNOON DUE TO DIFFUSE
NATURE OF THE BOUNDARY AND EXTENSIVE CLOUD COVER THAT PASSED
ACROSS OUR SOUTHERN CWA THIS MORNING. BY 17Z THE BOUNDARY APPEARED
TO BE LYING FROM THE SOUTHWEST TO THE NORTHEAST PART OF THE CWA.
BEST SURFACE MOISTURE POOLING IN THIS AREA WITH UPPER 60S FOR
DEWPOINTS...AS COMPARED TO THE 50S NORTHWEST OF THE CWA. TO GO
ALONG WITH THIS...ML CAPES THE HIGHEST HERE AT 17Z WITH VALUES
AROUND 1500 J/KG. 0-6 KM SHEAR AT 50 KT ALONG NEB/SDAK BORDER...30
KT IN THE NORTHERN PART OF THE CWA AND LESS THAN THAT IN OUR
SOUTH.
FIRST QUESTION THEN IS WILL THUNDERSTORMS POP THIS AFTERNOON AND
TO WHAT EXTENT. THE 4KM WRF DEVELOPS CONVECTION ALONG THE FRONT
LATE THIS AFTERNOON AND THEN SAGS IT SOUTH DURING THE EVENING. IT
ALSO DEVELOPS AN MCS OVER NORTHEAST COLORADO THIS EVENING AND THEN
SLIDES IT EAST ACROSS NORTHERN KS OVERNIGHT. THIS SCENARIO ALSO
SUPPORTED BY SEVERAL RUNS OF THE HRRR TODAY. QUESTION HERE IS WILL
THE TRACK TAKE IT ACROSS OR JUST SOUTH OF OUR KS COUNTIES. WILL
MOST LIKELY KEEP AT LEAST A SLIGHT CHANCE IN THE NORTH LATER TODAY
INTO THE EVENING WITH A LITTLE BIT BETTER CHANCES ACROSS KS. SO
FAR SEVERE CHANCES LATER THIS AFTERNOON DO NOT LOOK THAT PROMISING
DUE TO THE LACK OF MID LEVEL FORCING AND WEAK SHEAR. COULD SEE
SOME SEVERE THUNDERSTORMS OVERNIGHT IF MCS SCENARIO MATERIALIZES.
THE SITUATION IS NOT MUCH CLEARER FOR SUNDAY WITH LOCATIONS OF THE
SURFACE BOUNDARIES STILL A BIT OF A QUESTION. IT DOES LOOK LIKE WE
COULD HAVE SOME MID LEVEL SUPPORT AND INSTABILITY AND SHEAR
PARAMETERS LOOKING MORE FAVORABLE THAN THEY DO TODAY. LATEST DAY 2
OUTLOOK FROM SPC HAS AREA IN A SLIGHT RISK. THEY MENTION THAT
CONDITIONS LOOK FAVORABLE FOR A LINEAR SYSTEM TO DEVELOP WITH
DAMAGING WINDS THE GREATEST THREAT ALTHOUGH EARLY ON WE COULD SEE
DISCRETE CELLS WITH LARGE HAIL...DAMAGING WINDS AND A FEW
TORNADOES POSSIBLE. WILL PROBABLY HAVE HIGHEST POPS IN THE SOUTH
FOR SUNDAY...CLOSER TO EXPECTED LOCATION OF THE SURFACE BOUNDARY.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 306 PM CDT SAT JUN 15 2013
GUIDANCE FROM THE NAM...OPERATIONAL GFS...EC...AND SREF-MEAN
SUGGESTS A MID TO UPPER LEVEL RIDGE WILL LINGER OVER THE ROCKY
MOUNTAIN RANGE MONDAY AND TUESDAY...THUS HELPING PROMOTE
NORTHWESTERLY MID TO UPPER LEVEL FLOW OVER THE CENTRAL PLAINS.
PERIODIC MID LEVEL PERTURBATIONS ARE EXPECTED TO PUSH OVER OUR
AREA WITHIN THE MEAN MID LEVEL FLOW...THUS PRESENTING PERIODS OF
INCREASED OMEGA. SUNDAY NIGHT INTO EARLY MONDAY MORNING IS ONE
SUCH TIME PERIOD WITH QPF FIELDS FROM THE OPERATIONAL GFS...EC
...SREF-MEAN...AND TO A LESSER EXTENT THE NAM...ALL SUGGESTING
MEASURABLE PRECIPITATION WILL BE REALIZED OVER OUR AREA.
MAINTAINED THE ~50% POPS INHERITED FROM THE PREVIOUS FORECAST FOR
SUNDAY NIGHT INTO EARLY MONDAY MORNING AS A RESULT. MONDAY INTO
TUESDAY...POP-RELATED DETAILS BECOME MURKY AT BEST...WITH VARIOUS
MODELS SUGGESTING THE AFOREMENTIONED MID LEVEL PERTURBATIONS WILL
MOVE OVER SOME PORTION OF OUR CWA AT SOME POINT IN TIME. RESULTANT
QPF FIELDS ARE ALL OVER THE PLACE AS A RESULT...THUS MAKING IT
DIFFICULT TO PIN DOWN AN EXACT LOCATION TO PLACE POPS. THAT BEING
SAID...THERE DOES SEEM TO BE SOME AGREEMENT BETWEEN THE
NAM...EC...AND SREF-MEAN OF MEASURABLE PRECIPITATION BEING
REALIZED SOMEWHERE ACROSS OUR WEST/SOUTHWESTERN CWA BOTH MONDAY
AND TUESDAY DURING THE AFTERNOON AND EVENING HOURS. FORECAST
PROXIMITY SOUNDINGS FROM ACROSS OUR WEST/SOUTHWEST...PER THE
NAM...EC...AND EVEN THE OPERATIONAL GFS DESPITE ITS DRY QPF OUTPUT
ON BOTH DAYS...SUGGEST STEEP LOW TO MID LEVEL LAPSE RATES MAY
ALLOW A FEW LOCATIONS TO AUTO-CONVECT ACROSS THE HIGHER TERRAIN OF
OUR WEST/SOUTHWESTERN CWA. GIVEN THE MODEST CONSENSUS FROM MODEL
QPF FIELDS...AS WELL AS THE LOW TO MID LEVEL LAPSE RATES SUGGESTED
BY THE AFOREMENTIONED FORECAST PROXIMITY SOUNDINGS...WENT AHEAD
WITH ~20% POPS ACROSS ROUGHLY THE WEST/SOUTHWESTERN ONE-THIRD OF
OUR CWA FOR THE AFTERNOON AND EVENING HOURS ON MONDAY AND TUESDAY.
WEDNESDAY AND BEYOND...THE OPERATIONAL GFS AND EC BOTH SUGGEST MID
TO UPPER LEVEL FLOW WILL TRANSITION FROM THE NORTHWEST TO MORE OF
A SOUTHWESTERLY DIRECTION...WITH MULTIPLE MID LEVEL PERTURBATIONS
MOVING OVER THE REGION. ALLBLEND RESPONDED BY PROVIDING 20-50%
POPS FOR VARIOUS POINTS ACROSS OUR CWA DURING VARIOUS TIME
PERIODS. TIMING AND POSITION DETAILS WITH RESPECT TO ANY OF THE
MID LEVEL PERTURBATIONS MID TO LATE NEXT WEEK WILL LIKELY NOT
BECOME ANY MORE CLEAR FOR A COUPLE MORE DAYS AND AS A RESULT...THE
PROBABILITY OF SUCCESSFULLY IMPROVING THE FORECAST AS PROVIDED BY
ALLBLEND IS LOW. GIVEN THIS LOW PROBABILITY...OPTED TO LEAVE THE
ALLBLEND POPS UNCHANGED FOR THE MOST PART.
FORECAST PROXIMITY SOUNDINGS FROM ACROSS OUR CWA...IN PARTICULAR
THE NAM...SUGGEST ASCENDING PARCELS ROOTED TO BETWEEN 825MB AND
750MB WILL HAVE ~1500J/KG TO WORK WITH SUNDAY NIGHT INTO EARLY
MONDAY MORNING. IN ADDITION TO THIS POTENTIAL ENERGY...DEEP LAYER
BULK SHEAR VALUES OF ~30KTS ARE ALSO FORECAST ACROSS MUCH OF OUR
AREA. ALTHOUGH CONFIDENCE IS NOT OVERLY HIGH WITH RESPECT TO
SEVERE WEATHER CHANCES SUNDAY NIGHT INTO EARLY MONDAY
MORNING...WILL GO AHEAD AND MAINTAIN SEVERE WEATHER WORDING IN THE
HWO FOR SUNDAY NIGHT AND EARLY MONDAY MORNING. SEVERE WEATHER
COULD BE OBSERVED SHOULD THUNDERSTORM ACTIVITY BE REALIZED ACROSS
OUR WEST/SOUTHWESTERN CWA DURING THE AFTERNOON AND/OR EVENING
HOURS MONDAY AND TUESDAY...WITH THE NAM...OPERATIONAL GFS...AND EC
ALL SUGGESTING DEEP LAYER MUCAPE VALUES GENERALLY IN THE
2000-3000J/KG RANGE. DEEP LAYER BULK SHEAR VALUES ON THE ORDER OF
~30KTS ARE ALSO FORECAST. GIVEN ALL THIS...WILL GO AHEAD AND
OUTLOOK THE THREAT FOR ISOLATED SEVERE WEATHER BOTH MONDAY AND
TUESDAY ACROSS OUR WEST/SOUTHWEST. MUCH LIKE THE OVERALL POP
FORECAST...DETAILS REGARDING SEVERE WEATHER TIMING AND POSITION
WEDNESDAY AND BEYOND WILL NOT LIKELY BECOME ANY MORE CLEAR FOR A
COUPLE MORE DAYS AND AS A RESULT...WILL CONTINUE THE GENERAL
THUNDERSTORM MENTION IN THE HWO FOR THE TIME BEING.
LITTLE CHANGE IN THE LOW LEVEL AIRMASS SHOULD PRESENT SIMILAR
TEMPERATURES BETWEEN MONDAY AND WEDNESDAY...WITH AFTERNOON HIGH
TEMPERATURE GENERALLY IN THE 80S CURRENTLY FORECAST. LOW LEVEL
SOUTHERLY FLOW AND RESULTANT LOW LEVEL WARM AIR ADVECTION
BEGINNING WEDNESDAY HOWEVER...SHOULD PROMOTE A WARMING TREND TO
FINISH OUT THE FORECAST PERIOD...WITH AFTERNOON HIGH TEMPERATURES
IN THE UPPER 80S AND 90S EXPECTED FOR THE MOST LOCATIONS BY LATE
NEXT WEEK. OVERNIGHT TEMPERATURES IN THE 60S ARE FORECAST FOR MOST
LOCATIONS THROUGH WEDNESDAY NIGHT...WITH LOWS CREEPING INTO THE
70S FOR SOME LOCATIONS BY LATE NEXT WEEK.
&&
.AVIATION...(FOR THE 00Z KGRI TAF THROUGH 00Z SUNDAY EVENING)
ISSUED AT 630 PM CDT SAT JUN 15 2013
PREVAILING VFR CONDITIONS ARE EXPECTED FOR THE NEXT 24 HOURS WITH
TWO DISTINCT CHANCES FOR THUNDERSTORMS EXPECTED TO IMPACT THE
TERMINAL AND THE SLIGHTEST CHANCE FOR SOME MVFR BR DEVELOPING NEAR
DAYBREAK. FOR TONIGHT...EXPECT CONVECTION FORMING OVER THE HIGH
PLAINS TO TRANSITION EAST SOUTHEASTWARD TOWARDS THE LOCAL
AREA...AND MENTIONED A VCTS AFTER 16/06Z AS THE BULK OF THE
ACTIVITY APPEARS TO BE HEADED WELL TO THE SOUTH OF THE TERMINAL.
THEN AS THE WINDS SHIFT AND BECOME EASTERLY TOWARDS
DAYBREAK...COULD SEE ENOUGH LIGHT UPSLOPE FLOW AND RADIATIONAL
COOLING FOR SOME MVFR VSBYS...BUT ANY BR THAT DOES DEVELOP WILL BE
THIN AND BRIEF...WITH A CHANCE OF THUNDERSTORMS RETURNING BY
16/18Z AS A MID LEVEL DISTURBANCE CROSSES THE PLAINS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...EWALD
LONG TERM...BRYANT
AVIATION...SAR
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1245 PM CDT FRI JUN 14 2013
.DISCUSSION...
HAVE AGAIN TWEAKED FORECAST THROUGH THE REMAINDER OF THE
AFTERNOON. A WARM FRONTAL FEATURE IS DEVELOPING ACROSS EASTERN
NEB...AND SATELLITE TRENDS INDICATE SOME CLEARING IS TAKING
PLACE...WITH TEMPS INTO THE 80S AND DEWPOINTS ALREADY BREACHING
70 IN SOUTHEAST NEB. THOUGH UPPER-LEVEL PATTERN IS FAIRLY
BENIGN...SURFACE CONVERGENCE SHOULD BE ENOUGH TO PROMPT
THUNDERSTORM DEVELOPMENT BEGINNING IN THE LATE AFTERNOON.
HOWEVER...DO THINK THAT UPPER-LEVEL FORCING IS WEAK ENOUGH THAT
SIGNIFICANT COVERAGE IS NOT EXPECTED BEFORE 00Z. HAVE BACKED
AFTERNOON POPS DOWN TO CHANCE/SCATTERED CATEGORY...WITH COVERAGE
WORDING...AND TIGHTENED LOCATION OF MOST LIKELY THUNDERSTORM
DEVELOPMENT.
MAYES
&&
.AVIATION...
18Z TAFS FOR KOMA...KLNK...AND KOFK.
PREVAILING VFR CONDITIONS ARE EXPECTED THROUGH THE TAF CYCLE.
THUNDERSTORMS ARE LIKELY TO DEVELOP IN CENTRAL TO EASTERN NEBRASKA
BY AROUND 00Z AND PERSIST FOR SEVERAL HOURS. HAVE INCLUDED A TEMPO
MENTION AT ALL SITES FOR NOW WITH A BEST GUESS AT TIME WINDOW THAT
SITES WOULD BE AFFECTED BY STORMS. SHOULD ANY OF THE HEAVIER
STORMS MOVE OVER A TAF SITE...WOULD FORESEE POSSIBILITY FOR MVFR
TO IFR CONDITIONS FOR A SHORT TIME...BUT CONFIDENCE IS TOO LOW TO
INTRODUCE AT THIS TIME. IN WAKE OF STORMS...SHOULD SEE IMPROVING
CONDTIONS FOR OVERNIGHT AND MORNING. WINDS WILL SHIFT BY LATE
MORNING TO NORTHEASTERLY AT KOFK...AND NORTH/NORTHWESTERLY AT
KOMA/KLNK.
MAYES
&&
.PREV DISCUSSION... /ISSUED 951 AM CDT FRI JUN 14 2013/
DISCUSSION...
MADE A FEW UDPATES FOR ONGOING MORNING TRENDS. CONVECTION IS
SLIDING EASTWARD OUT OF WESTERN IOWA...AND AREA OF LIGHT SHOWERS
ALONG THE I-80 CORRIDOR BETWEEN SEWARD AND LINCOLN IS DISSIPATING.
HOWEVER...A NEW LINE OF SHOWERS AND ISOLATED THUNDER HAS CROPPED
UP FROM ALBION TO YANKTON. HAVE ADJUSTED POPS FOR THESE
TRENDS...AND DO EXPECT ACTIVITY TO FADE/MOVE OUT THROUGH THE
REMAINDER OF THE MORNING HOURS...WITH THUNDERSTORMS DEVELOPING
AGAIN LATER THIS AFTERNOON...AND A WINDOW OF DRY WEATHER BETWEEN.
MAYES
PREV DISCUSSION... /ISSUED 714 AM CDT FRI JUN 14 2013/
AVIATION...
12Z TAFS FOR KOMA...KLNK...KOFK.
VFR CEILINGS ARE FORECAST ACROSS MUCH OF THE AREA DURING THE
DAY...EXCEPT IN THE VICINITY OF THUNDERSTORMS WHERE CEILINGS CAN
BE EXPECTED TO BE MVFR. SOUTHERLY WINDS ARE FORECAST TO BECOME
GUSTY BY 18Z WITH GUSTS AS HIGH AS 25 KT. SHRA OVER THE FORECAST
AREA SHOULD DIMINISH BY MID MORNING AND THEN TSRA IS EXPECTED TO
DEVELOP...ESPECIALLY AFTER 21Z.
SMITH
PREV DISCUSSION... /ISSUED 340 AM CDT FRI JUN 14 2013/
DISCUSSION...
MAIN FORECAST CONCERN IS CONVECTION THIS MORNING...THEN AGAIN
THIS AFTERNOON AND TONIGHT...
LATEST WATER VAPOR IMAGERY AND RAP 500MB ANALYSIS SHOW A TROUGH AXIS
EXTENDING FROM LOW PRESSURE IN ALBERTA SOUTHWARD TOWARD NORTHERN
NEVADA. DOWNSTREAM...A HIGH PRESSURE RIDGE AXIS EXTENDS FROM THE
SOUTHERN PLAINS INTO CENTRAL MANITOBA. AN EMBEDDED WEAK SHORTWAVE
CONTINUES TO MOVE UP THE BACKSIDE OF THE RIDGE AND INTO CENTRAL
NEBRASKA. WIDELY SCATTERED THUNDERSTORMS CONTINUE IN ADVANCE OF
THIS SHORTWAVE AND THESE ARE SLOWLY MOVING EAST-NORTHEAST. MOST
LIKELY SCENARIO TO PLAY OUT SEEMS TO BE WHAT THE HRRR AND RAP
HAVE BEEN INDICATING AND THAT IS FOR THE CONVECTION ASSOCIATED
WITH THE ABOVE MENTIONED SHORTWAVE TO CONTINUE TO CLUSTER TOGETHER AND
DRIFT EAST ACROSS THE CWA THROUGH THE MORNING WHERE STRONG
ISENTROPIC UPGLIDE RESIDES. SOME OF THESE MAY CONTAIN MARGINALLY
SEVERE HAIL...AIDED BY A VEERED 35-45KT LOW LEVEL JET.
CLOUD COVER FROM MORNING CONVECTIVE ACTIVITY WILL LIKELY INHIBIT
STRONG HEATING INITIALLY. AS HIGH PLAINS SFC LOW PRESSURE SLIDES
EAST TODAY...A WARM FRONT WILL EXTEND WEST TO EAST ACROSS THE
FORECAST AREA BRINGING A RAPID WARM UP TO THE AREA THIS
AFTERNOON...ESPECIALLY IN OUR SOUTH. IN ADDITION...SFC DEWPOINTS
ARE PROGGED TO RISE INTO THE LOWER 70S BY AFTERNOON WHICH MAY BE A
BIT HIGH AND PUSHES FORECASTED SFC BASED CAPE VALUES INTO THE 4000
J/KG RANGE. WITH AN INCREASING SOUTHWEST LOW LEVEL JET EARLY IN
THE EVENING AIDING TSTMS...THINK BUSIEST TIMEFRAME IN TERMS OF ANY
SEVERE STORMS WILL BE FROM ABOUT 23Z-03Z NEAR THE SFC BOUNDARY.
THIS WILL MOST LIKELY LINGER INTO THE OVERNIGHT HOURS AS A
POSSIBLE MCS AS THE BOUNDARY REMAINS IN THE AREA. ALL THIS LIMITED
OF COURSE BY CAPPING INVERSION...ESPECIALLY THIS AFTERNOON.
WILL CONTINUE TO CARRY POPS THROUGH THE WEEKEND AS THE BOUNDARY
REMAINS OVER THE AREA ALTHOUGH DO NOT THINK WE WILL HAVE A
CONTINUOUS PERIOD OF THUNDERSTORMS THROUGHOUT THE ENTIRE WEEKEND.
WITH WESTERLY MID LEVEL FLOW...HIGHER POPS ARE WARRANTED WITH
THIS BOUNDARY EXTENDING OVER THE AREA.
NO CHANGES INTO THE LATER PERIODS WITH DRIER WEATHER ON TAP FOR
MONDAY AND TUESDAY AND A BIT MORE ACTIVE MID TO LATE WEEK.
KERN
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1236 PM CDT FRI JUN 14 2013
.UPDATE...
ISSUED AT 1236 PM CDT FRI JUN 14 2013
TODAY WILL MARK THE 4TH DAY IN A ROW OF 100+ TEMPS AT PGH
/PHILLIPSBURG KS/.
HIGH TEMPS WERE INCREASED OVER MUCH OF S-CNTRL NEB WITH THE 11 AM
UPDATE. THE ONLY CHANGES WITH THIS ENHANCED SHORT-TERM FCST /ESTF/
UPDATE WERE TO GET THE HOURLY FCST BACK ON THE OBSERVED TREND LINE
AT A A COUPLE COOLER LOCATIONS. ALSO NUDGED WINDS UP A COUPLE KTS.
THE BULK OF THE AFTN-TNGT-SAT FCST WILL BE UPDATED AND IN ITS
PROBABLE FINAL FORM BY 130 PM IN AN EFFORT TO MONITOR SHORT-TERM
MESOSCALE TRENDS AS WE AWAIT CONVECTIVE INITIATION.
UPDATE ISSUED AT 1121 CDT FRI JUN 14 2013
THE WARM FRONT HAS BEEN REINFORCED BY TSTM ACTIVITY OVER THE LAST
12 HRS. IT LIES ROUGHLY FROM NEAR IMPERIAL-PHILLIPSBURG KS-KANSAS
CITY. EXPECT FRONT TO LIFT N. MEANWHILE...THE APPROACHING COOL
FRONT IS OVER THE PANHANDLE BACK TO NEAR DENVER.
IMPORTANT MESOSCALE PARAMETERS:
MLCAPE 2000-3500 J/KG.
EFFECTIVE SHEAR 25 KTS.
LCL HGTS 6-8K FT.
2-7 KM SHEAR VECTOR ORIENTATION: PARALLEL TO THE COOL FRONT.
0-3 KM SRH WILL BE E OF THE WARM FRONT...WHICH SHOULD BE E OF THE
FCST AREA BY THE TIME TSTMS ERUPT. THE SUPERCELL COMPOSITE
PARAMETER WILL ALSO BE GREATEST E OF THE WARM FRONT AS WELL.
BOTTOM LINE...MODERATE SHEAR...DRY SUB-CLOUD LAYER...AND SHEAR
ORIENTATION PARALLEL TO THE FRONT WILL RESULT IN OUTFLOW DOMINANT
MULTICELL TSTMS THAT WILL TEND TO ORGANIZE INTO LINES. THE PRIMARY
THREAT WILL BE DAMAGING MICROBURST WINDS UP TO 70 MPH /POSSIBLY
HIGHER/. INSTABILITY WILL BE SIGNIFICANT...BUT LIMITED SHEAR WILL
LIMIT THE LARGEST HAIL TO THE SIZE OF GOLF BALLS.
IF FOR SOME REASON THE COOLER/DENSE AIR PREVAILS...AND THE WARM
FRONT REMAINS OVER PART OF THE FCST AREA...SAY FROM ORD-GRAND
ISLAND-HEBRON...THEN LCL HGTS WILL BE LOWER AND SHEAR WILL BE
HIGHER AND WE`LL NEED TO WATCH FOR SUPERCELL/TORNADO POTENTIAL
OVER THE ERN FRINGE OF OUR FCST AREA. SINCE SUNSHINE IS OCCURRING
N OF THE FRONT...THIS IS A GOOD SIGN THAT THE FRONT SHOULD LIFT N
AND CLEAR THE FCST AREA.
UPDATE ISSUED AT 952 AM CDT FRI JUN 14 2013
OFF TO A BIT OF SLOW START DUE TO MONITORING RADAR THRU 830 AM.
THERE WERE A COUPLE OF NEAR-SVR STORMS THAT TRACKED FROM NEAR
HANSEN E ALONG THE HAMILTON-CLAY COUNTY LINE. WE SAW 50 DBZ UP TO
32K FT.
THE MRNG SHWRS/TSTMS WERE WARM FRONT GENERATED. THE HEAT WILL NOW
FOLLOW.
FCST HOURLY TEMPS WERE RUNNING WAY TOO WARM IN THE RAIN-COOLED
AREAS. SO SOME MAJOR ADJUSTMENTS HAVE BEEN MADE. CLEARING IS
HEADING E PER VIS SAT SO TEMPS SHOULD ROCKET UP. ALSO ADJUSTED
POPS AS SHWRS/TSTMS HAVE NEARLY CLEARED THE FCST AREA. POPS WERE
ALSO BLENDED WITH MULTIPLE HI-RES MODELS FROM 23Z-06Z TO COVER
TSTMS EXPECTED TO ERUPT.
FURTHER EVALUATION OF THE SITUATION WILL BE ON-GOING AND WE`LL
PROBABLY HAVE MORE IN AN AFD LATER THIS MRNG. 12Z SOUNDINGS ARE
SURPRISINGLY MOIST UP TO 850 MB. HOWEVER...WITH HIGHS OF 94-104F
AT 5 PM...SFC TEMP/DWPT SPREADS WILL STILL RESULT IN SUBSTANTIAL
DRYING BELOW CLOUD BASES THAT DEVELOP.
BASED ON BEST-VERIFYING HIGH TEMP GUIDANCE WE WILL PROBABLY BE
RAISING HIGH TEMPS SEVERAL DEGS IN THE TRI-CITIES AREA PENDING
FURTHER EVALUATION BEFORE NOON.
SLGT RISK CONTINUES FOR LATE THIS AFTN-EVNG.
PLEASE FOLLOW LATEST UPDATES FROM THE SPC VIA THEIR OUTLOOKS AND
MESOSCALE DISCUSSIONS...AND ALL FUTURE STATEMENTS/WATCHES/WARNINGS
FROM THIS OFFICE.
SKYWARN: BE ALERT FOR ACTIVATION IN THE 21Z-00Z TIME FRAME.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 413 AM CDT FRI JUN 14 2013
THE PRIMARY FORECAST CONCERN CENTERS AROUND THE CHANCE OF
THUNDERSTORMS EARLY THIS MORNING AND THEN AGAIN LATER THIS
AFTERNOON. SOME THUNDERSTORMS LATE THIS AFTERNOON AND EVENING WILL
LIKELY BE SEVERE.
THE FIRST ROUND OF THUNDERSTORMS HAVE BEEN WEAKENING AS THEY TRACK
EAST. THE HRRR SEEMS TO HAVE A GOOD HANDLE ON THESE STORMS AND
TRACKS THEM ALL THE WAY ACROSS OUR FORECAST AREA GENERALLY ALONG
THE INTERSTATE 80/HWY 6 CORRIDOR. CURRENT EXPECTATION IS THAT ALL
OF THESE THUNDERSTORMS WILL HAVE EITHER DECAYED OR BE EAST OF OUR
FORECAST AREA BY MID MORNING WITH DRY CONDITIONS FROM LATE
MORNING THROUGH MID AFTERNOON. THE HIGH CIRRUS LEFT OVER FROM THE
MORNING THUNDERSTORMS WILL THIN AND WE SHOULD SEE A GOOD DEAL OF
SUNSHINE TODAY HELPING TEMPERATURES SKY ROCKET. AN INCREASING
SOUTH WIND IN THE WARM SECTOR TODAY...WHICH WILL INCLUDE ALL OF
OUR FORECAST AREA EXCEPT MAYBE OUR FAR NORTHERN ZONES WILL ALSO
HELP TO GIVE TEMPERATURES A BOOST. EXPECT AFTERNOON HIGHS TO RANGE
FROM AROUND 90 IN OUR FAR NORTH AROUND ORD TO OVER 100 ACROSS MUCH
OF NORTH CENTRAL KANSAS.
THERE IS GOOD FORECAST MODEL AGREEMENT THAT AFTERNOON
THUNDERSTORMS WILL EVENTUALLY OVERCOME AN ELEVATED CAP
AND INITIATE ALONG A SFC FRONT THAT WILL STRETCH FROM NORTHEAST
NEBRASKA INTO SOUTH CENTRAL NEBRASKA AND NORTHWEST KANSAS. MLCAPE
VALUES ALONG THE FRONT WILL RANGE FROM 2000 TO 4000 J/KG MAKING
FOR A VERY UNSTABLE ATMOSPHERE. 0-6KM WIND SHEAR WILL BE MORE
MARGINAL AT 25 TO 35 KTS. THE COMBINATION OF STRONG
INSTABILITY...AT LEAST MARGINAL SHEAR...AND A FRONTAL BOUNDARY
SHOULD BE MORE THAN SUFFICIENT TO ALLOW FOR SEVERAL SEVERE
THUNDERSTORMS ACROSS OUR FORECAST AREA LATE THIS AFTERNOON AND
EVENING. EXPECT INITIATION WILL LIKELY BE AFTER 4 PM WITH THE
GREATEST SEVERE WEATHER THREAT IN THE 5 PM TO 10 PM TIME FRAME.
REDEVELOPMENT AND POSSIBLE TRAINING OF THUNDERSTORMS ALONG THE
FRONT WILL BE POSSIBLE LEADING TO LOCALIZED HEAVY RAIN. THE
HIGHEST CHANCE OF THUNDERSTORMS WILL GENERALLY BE NEAR HIGHWAY 30
FROM MERRICK COUNTY DOWN INTO GRAND ISLAND AND KEARNEY...AND THEN
SOUTHWEST INTO GOSPER AND FURNAS COUNTY. THE CHANCE OF
THUNDERSTORMS WILL DECREASE PRETTY FAST AS YOU HEAD SOUTHEAST OF
THIS CORRIDOR INTO NORTH CENTRAL KANSAS. THE PRIMARY SEVERE
WEATHER THREATS WILL BE LARGE HAIL TO THE SIZE OF GOLFBALLS AND
WIND GUSTS TO 70 MPH. WIND IS A BIG CONCERN DUE TO THE INVERTED V
FORECAST SOUNDING AND STEEP LAPSE RATES ALONG WITH THE OBVIOUSLY
HIGH CAPE. THE TORNADO THREAT WILL BE LIMITED DUE TO GENERALLY
WEAK LOW LEVEL SHEAR AND HIGHER LCL HEIGHTS. THE LIMITED TORNADO
THREAT WILL BE ACROSS OUR NORTHEASTERN CWA PRIMARY FOR THE KEARNEY
AND GRAND ISLAND AREAS AND POINTS NORTHEAST WHERE LCL HEIGHTS WILL
BE THE LOWEST AND THERE MIGHT BE SOME BACKING OF THE SFC WIND BY
EARLY EVENING...BUT AGAIN THIS IS ONLY A LIMITED THREAT WITH THE
PRIMARY THREATS TODAY BEING BIG HAIL AND STRONG THUNDERSTORM
WINDS.
THE CONVECTION WILL SLOWLY PUSH EAST TONIGHT AND AREAS ALONG AND
NORTH OF HIGHWAY 6 MAY ALSO SEE SOME ADDITIONAL THUNDERSTORM
REDEVELOPMENT DURING THE LATE EVENING HOURS AS THE LOW LEVEL JET
STRENGTHENS AND NOSES INTO OUR NEBRASKA ZONES.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 413 AM CDT FRI JUN 14 2013
MAIN FORECAST CONCERNS WILL BE CHANCES FOR THUNDERSTORMS AND
TEMPERATURES.
AN ACTIVE WEATHER PATTERN WILL BE FOUND ACROSS THE AREA THROUGH THIS
PERIOD. MODELS ARE SIMILAR IN THE MAIN FEATURES WITH SUBTLE
DIFFERENCES IN THE FINER DETAILS. SEVERAL UPPER LEVEL LOWS MOVE
THROUGH THE AREA DURING THE PERIOD AND EACH HAS THE POTENTIAL FOR
SOME THUNDERSTORMS. WITH THIS IN MIND THERE ARE CHANCES FOR
THUNDERSTORMS NEARLY EVERY PERIOD FOR PORTIONS OF THE AREA.
THE FIRST UPPER LEVEL LOW MOVES THROUGH THE AREA SATURDAY.
THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG A NEARLY STATIONARY
FRONT. THE QUESTION IS WHERE THIS FRONT WILL BE AND WHEN THE
THUNDERSTORMS DEVELOP. MODELS ARE SIMILAR THAT IT IS DRAPED ACROSS
THE CENTRAL TO SOUTHERN PART OF THE FORECAST AREA. HAVE KEPT CHANCES
ACROSS THE AREA WITH THUNDERSTORMS ALONG THE FRONT. THUNDERSTORM
CHANCES CONTINUE INTO SATURDAY NIGHT AS ANOTHER UPPER LEVEL WAVE
MOVES INTO THE AREA SATURDAY NIGHT AND THUNDERSTORMS ON THE HIGH
PLAINS START TO MOVE INTO THE AREA LATE SATURDAY NIGHT. THE NEXT
WAVE AFFECTS THE AREA SUNDAY AND SUNDAY NIGHT. THE BEST CHANCE FOR
THUNDERSTORMS WITH THIS ROUND WILL BE SUNDAY NIGHT IN THE SOUTHERN
PART OF THE FORECAST AREA.
THERE IS A BREAK ON MONDAY AS A SURFACE HIGH PRESSURE SYSTEM PUSHES
INTO THE AREA. THE BREAK IS SHORT LIVED FOR PORTIONS OF THE AREA.
ANOTHER UPPER LEVEL WAVE STARTS TO AFFECT THE CENTRAL HIGH PLAINS
MONDAY NIGHT THROUGH TUESDAY NIGHT...BUT WITH AN UPPER LEVEL RIDGE
ACROSS THE AREA AND THE SURFACE HIGH MOVING TO THE EAST THE STORMS
SHOULD BE MAINLY IN THE WESTERN PART OF THE FORECAST AREA.
WEDNESDAY THROUGH THURSDAY A SERIES OF UPPER LEVEL WAVES MOVE
THROUGH THE AREA AND BRING CHANCES FOR THUNDERSTORMS TO THE FORECAST
AREA AGAIN. MODELS HAVE A FEW DIFFERENCES IN THE TIMING OF THE
PRECIPITATION.
TEMPERATURES THROUGH THE PERIOD WILL BE MOSTLY IN THE 80S WITH A
LITTLE VARIATION UP AND DOWN THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1236 PM CDT FRI JUN 14 2013
THIS AFTN: VFR THOUGH SCT TSTMS DEVELOPING AROUND 22Z WITH POCKETS
OF IFR VSBYS. THREAT IS COVERED WITH VCTS UNTIL WE CAN BE MORE
CERTAIN THE TERMINAL WILL ACTUALLY BE HIT. THESE TSTMS WILL
CONTAIN GUSTY WINDS WITH 40 KTS LIKELY AND 50 KTS POSSIBLE.
OUTSIDE OF TSTMS...S WINDS WILL GUST UP TO 30 KTS THIS AFTN AND
THEN DIMINISH AND BECOME VARIABLE 10 KTS OR LESS AS A COOL FRONT
APPROACHES. THERE MAY BE A PRIMARY WIND DIRECTION...BUT
DISAGREEMENT AMONGST MODEL GUIDANCE PRECLUDES A DEFINITE DIRECTION.
TNGT: VFR OUTSIDE OF SCT TSTMS THEN THREAT DIMINISHES BUT MAY NOT
END AFTER 04Z. TOO MUCH UNCERTAINTY TO INCLUDE VCTS AFTER 04Z BUT
IT MAY EVENTUALLY NEED TO BE INCLUDED.
SAT: SCT TSTMS CONTINUE THOUGH EXPECT VFR MOST OF THE TIME.
CIG CONFIDENCE: AVERAGE
VSBY CONFIDENCE: HIGH OUTSIDE OF TSTMS
WX CONFIDENCE: LOW DUE TO TIMING/OCCURRENCE OF TSTMS
WIND CONFIDENCE: LOW
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HALBLAUB
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1122 AM CDT FRI JUN 14 2013
.UPDATE...
ISSUED AT 1121 CDT FRI JUN 14 2013
THE WARM FRONT HAS BEEN REINFORCED BY TSTM ACTIVITY OVER THE LAST
12 HRS. IT LIES ROUGHLY FROM NEAR IMPERIAL-PHILLIPSBURG KS-KANSAS
CITY. EXPECT FRONT TO LIFT N. MEANWHILE...THE APPROACHING COOL
FRONT IS OVER THE PANHANDLE BACK TO NEAR DENVER.
IMPORTANT MESOSCALE PARAMETERS:
MLCAPE 2000-3500 J/KG.
EFFECTIVE SHEAR 25 KTS.
LCL HGTS 6-8K FT.
2-7 KM SHEAR VECTOR ORIENTATION: PARALLEL TO THE COOL FRONT.
0-3 KM SRH WILL BE E OF THE WARM FRONT...WHICH SHOULD BE E OF THE
FCST AREA BY THE TIME TSTMS ERUPT. THE SUPERCELL COMPOSITE
PARAMETER WILL ALSO BE GREATEST E OF THE WARM FRONT AS WELL.
BOTTOM LINE...MODERATE SHEAR...DRY SUB-CLOUD LAYER...AND SHEAR
ORIENTATION PARALLEL TO THE FRONT WILL RESULT IN OUTFLOW DOMINANT
MULTICELL TSTMS THAT WILL TEND TO ORGANIZE INTO LINES. THE PRIMARY
THREAT WILL BE DAMAGING MICROBURST WINDS UP TO 70 MPH /POSSIBLY
HIGHER/. INSTABILITY WILL BE SIGNIFICANT...BUT LIMITED SHEAR WILL
LIMIT THE LARGEST HAIL TO THE SIZE OF GOLF BALLS.
IF FOR SOME REASON THE COOLER/DENSE AIR PREVAILS...AND THE WARM
FRONT REMAINS OVER PART OF THE FCST AREA...SAY FROM ORD-GRAND
ISLAND-HEBRON...THEN LCL HGTS WILL BE LOWER AND SHEAR WILL BE
HIGHER AND WE`LL NEED TO WATCH FOR SUPERCELL/TORNADO POTENTIAL
OVER THE ERN FRINGE OF OUR FCST AREA. SINCE SUNSHINE IS OCCURRING
N OF THE FRONT...THIS IS A GOOD SIGN THAT THE FRONT SHOULD LIFT N
AND CLEAR THE FCST AREA.
UPDATE ISSUED AT 952 AM CDT FRI JUN 14 2013
OFF TO A BIT OF SLOW START DUE TO MONITORING RADAR THRU 830 AM.
THERE WERE A COUPLE OF NEAR-SVR STORMS THAT TRACKED FROM NEAR
HANSEN E ALONG THE HAMILTON-CLAY COUNTY LINE. WE SAW 50 DBZ UP TO
32K FT.
THE MRNG SHWRS/TSTMS WERE WARM FRONT GENERATED. THE HEAT WILL NOW
FOLLOW.
FCST HOURLY TEMPS WERE RUNNING WAY TOO WARM IN THE RAIN-COOLED
AREAS. SO SOME MAJOR ADJUSTMENTS HAVE BEEN MADE. CLEARING IS
HEADING E PER VIS SAT SO TEMPS SHOULD ROCKET UP. ALSO ADJUSTED
POPS AS SHWRS/TSTMS HAVE NEARLY CLEARED THE FCST AREA. POPS WERE
ALSO BLENDED WITH MULTIPLE HI-RES MODELS FROM 23Z-06Z TO COVER
TSTMS EXPECTED TO ERUPT.
FURTHER EVALUATION OF THE SITUATION WILL BE ON-GOING AND WE`LL
PROBABLY HAVE MORE IN AN AFD LATER THIS MRNG. 12Z SOUNDINGS ARE
SURPRISINGLY MOIST UP TO 850 MB. HOWEVER...WITH HIGHS OF 94-104F
AT 5 PM...SFC TEMP/DWPT SPREADS WILL STILL RESULT IN SUBSTANTIAL
DRYING BELOW CLOUD BASES THAT DEVELOP.
BASED ON BEST-VERIFYING HIGH TEMP GUIDANCE WE WILL PROBABLY BE
RAISING HIGH TEMPS SEVERAL DEGS IN THE TRI-CITIES AREA PENDING
FURTHER EVALUATION BEFORE NOON.
SLGT RISK CONTINUES FOR LATE THIS AFTN-EVNG.
PLEASE FOLLOW LATEST UPDATES FROM THE SPC VIA THEIR OUTLOOKS AND
MESOSCALE DISCUSSIONS...AND ALL FUTURE STATEMENTS/WATCHES/WARNINGS
FROM THIS OFFICE.
SKYWARN: BE ALERT FOR ACTIVATION IN THE 21Z-00Z TIME FRAME.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 413 AM CDT FRI JUN 14 2013
THE PRIMARY FORECAST CONCERN CENTERS AROUND THE CHANCE OF
THUNDERSTORMS EARLY THIS MORNING AND THEN AGAIN LATER THIS
AFTERNOON. SOME THUNDERSTORMS LATE THIS AFTERNOON AND EVENING WILL
LIKELY BE SEVERE.
THE FIRST ROUND OF THUNDERSTORMS HAVE BEEN WEAKENING AS THEY TRACK
EAST. THE HRRR SEEMS TO HAVE A GOOD HANDLE ON THESE STORMS AND
TRACKS THEM ALL THE WAY ACROSS OUR FORECAST AREA GENERALLY ALONG
THE INTERSTATE 80/HWY 6 CORRIDOR. CURRENT EXPECTATION IS THAT ALL
OF THESE THUNDERSTORMS WILL HAVE EITHER DECAYED OR BE EAST OF OUR
FORECAST AREA BY MID MORNING WITH DRY CONDITIONS FROM LATE
MORNING THROUGH MID AFTERNOON. THE HIGH CIRRUS LEFT OVER FROM THE
MORNING THUNDERSTORMS WILL THIN AND WE SHOULD SEE A GOOD DEAL OF
SUNSHINE TODAY HELPING TEMPERATURES SKY ROCKET. AN INCREASING
SOUTH WIND IN THE WARM SECTOR TODAY...WHICH WILL INCLUDE ALL OF
OUR FORECAST AREA EXCEPT MAYBE OUR FAR NORTHERN ZONES WILL ALSO
HELP TO GIVE TEMPERATURES A BOOST. EXPECT AFTERNOON HIGHS TO RANGE
FROM AROUND 90 IN OUR FAR NORTH AROUND ORD TO OVER 100 ACROSS MUCH
OF NORTH CENTRAL KANSAS.
THERE IS GOOD FORECAST MODEL AGREEMENT THAT AFTERNOON
THUNDERSTORMS WILL EVENTUALLY OVERCOME AN ELEVATED CAP
AND INITIATE ALONG A SFC FRONT THAT WILL STRETCH FROM NORTHEAST
NEBRASKA INTO SOUTH CENTRAL NEBRASKA AND NORTHWEST KANSAS. MLCAPE
VALUES ALONG THE FRONT WILL RANGE FROM 2000 TO 4000 J/KG MAKING
FOR A VERY UNSTABLE ATMOSPHERE. 0-6KM WIND SHEAR WILL BE MORE
MARGINAL AT 25 TO 35 KTS. THE COMBINATION OF STRONG
INSTABILITY...AT LEAST MARGINAL SHEAR...AND A FRONTAL BOUNDARY
SHOULD BE MORE THAN SUFFICIENT TO ALLOW FOR SEVERAL SEVERE
THUNDERSTORMS ACROSS OUR FORECAST AREA LATE THIS AFTERNOON AND
EVENING. EXPECT INITIATION WILL LIKELY BE AFTER 4 PM WITH THE
GREATEST SEVERE WEATHER THREAT IN THE 5 PM TO 10 PM TIME FRAME.
REDEVELOPMENT AND POSSIBLE TRAINING OF THUNDERSTORMS ALONG THE
FRONT WILL BE POSSIBLE LEADING TO LOCALIZED HEAVY RAIN. THE
HIGHEST CHANCE OF THUNDERSTORMS WILL GENERALLY BE NEAR HIGHWAY 30
FROM MERRICK COUNTY DOWN INTO GRAND ISLAND AND KEARNEY...AND THEN
SOUTHWEST INTO GOSPER AND FURNAS COUNTY. THE CHANCE OF
THUNDERSTORMS WILL DECREASE PRETTY FAST AS YOU HEAD SOUTHEAST OF
THIS CORRIDOR INTO NORTH CENTRAL KANSAS. THE PRIMARY SEVERE
WEATHER THREATS WILL BE LARGE HAIL TO THE SIZE OF GOLFBALLS AND
WIND GUSTS TO 70 MPH. WIND IS A BIG CONCERN DUE TO THE INVERTED V
FORECAST SOUNDING AND STEEP LAPSE RATES ALONG WITH THE OBVIOUSLY
HIGH CAPE. THE TORNADO THREAT WILL BE LIMITED DUE TO GENERALLY
WEAK LOW LEVEL SHEAR AND HIGHER LCL HEIGHTS. THE LIMITED TORNADO
THREAT WILL BE ACROSS OUR NORTHEASTERN CWA PRIMARY FOR THE KEARNEY
AND GRAND ISLAND AREAS AND POINTS NORTHEAST WHERE LCL HEIGHTS WILL
BE THE LOWEST AND THERE MIGHT BE SOME BACKING OF THE SFC WIND BY
EARLY EVENING...BUT AGAIN THIS IS ONLY A LIMITED THREAT WITH THE
PRIMARY THREATS TODAY BEING BIG HAIL AND STRONG THUNDERSTORM
WINDS.
THE CONVECTION WILL SLOWLY PUSH EAST TONIGHT AND AREAS ALONG AND
NORTH OF HIGHWAY 6 MAY ALSO SEE SOME ADDITIONAL THUNDERSTORM
REDEVELOPMENT DURING THE LATE EVENING HOURS AS THE LOW LEVEL JET
STRENGTHENS AND NOSES INTO OUR NEBRASKA ZONES.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 413 AM CDT FRI JUN 14 2013
MAIN FORECAST CONCERNS WILL BE CHANCES FOR THUNDERSTORMS AND
TEMPERATURES.
AN ACTIVE WEATHER PATTERN WILL BE FOUND ACROSS THE AREA THROUGH THIS
PERIOD. MODELS ARE SIMILAR IN THE MAIN FEATURES WITH SUBTLE
DIFFERENCES IN THE FINER DETAILS. SEVERAL UPPER LEVEL LOWS MOVE
THROUGH THE AREA DURING THE PERIOD AND EACH HAS THE POTENTIAL FOR
SOME THUNDERSTORMS. WITH THIS IN MIND THERE ARE CHANCES FOR
THUNDERSTORMS NEARLY EVERY PERIOD FOR PORTIONS OF THE AREA.
THE FIRST UPPER LEVEL LOW MOVES THROUGH THE AREA SATURDAY.
THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG A NEARLY STATIONARY
FRONT. THE QUESTION IS WHERE THIS FRONT WILL BE AND WHEN THE
THUNDERSTORMS DEVELOP. MODELS ARE SIMILAR THAT IT IS DRAPED ACROSS
THE CENTRAL TO SOUTHERN PART OF THE FORECAST AREA. HAVE KEPT CHANCES
ACROSS THE AREA WITH THUNDERSTORMS ALONG THE FRONT. THUNDERSTORM
CHANCES CONTINUE INTO SATURDAY NIGHT AS ANOTHER UPPER LEVEL WAVE
MOVES INTO THE AREA SATURDAY NIGHT AND THUNDERSTORMS ON THE HIGH
PLAINS START TO MOVE INTO THE AREA LATE SATURDAY NIGHT. THE NEXT
WAVE AFFECTS THE AREA SUNDAY AND SUNDAY NIGHT. THE BEST CHANCE FOR
THUNDERSTORMS WITH THIS ROUND WILL BE SUNDAY NIGHT IN THE SOUTHERN
PART OF THE FORECAST AREA.
THERE IS A BREAK ON MONDAY AS A SURFACE HIGH PRESSURE SYSTEM PUSHES
INTO THE AREA. THE BREAK IS SHORT LIVED FOR PORTIONS OF THE AREA.
ANOTHER UPPER LEVEL WAVE STARTS TO AFFECT THE CENTRAL HIGH PLAINS
MONDAY NIGHT THROUGH TUESDAY NIGHT...BUT WITH AN UPPER LEVEL RIDGE
ACROSS THE AREA AND THE SURFACE HIGH MOVING TO THE EAST THE STORMS
SHOULD BE MAINLY IN THE WESTERN PART OF THE FORECAST AREA.
WEDNESDAY THROUGH THURSDAY A SERIES OF UPPER LEVEL WAVES MOVE
THROUGH THE AREA AND BRING CHANCES FOR THUNDERSTORMS TO THE FORECAST
AREA AGAIN. MODELS HAVE A FEW DIFFERENCES IN THE TIMING OF THE
PRECIPITATION.
TEMPERATURES THROUGH THE PERIOD WILL BE MOSTLY IN THE 80S WITH A
LITTLE VARIATION UP AND DOWN THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 556 AM CDT FRI JUN 14 2013
SHOWERS AND THUNDERSTORMS WILL TRACK THROUGH KGRI EARLY THIS
MORNING WITH DRY WEATHER EXPECTED BY LATE MORNING THROUGH EARLY
AFTERNOON. THE FRONT WILL SINK TO AROUND KGRI BY MID AFTERNOON AND
THEN STALL OUT RESULTING IN FAIRLY LIGHT AND SHIFTY WINDS. WILL
STILL HAVE TO WATCH OUT FOR GUSTY THUNDERSTORM WINDS DURING THE
LATE AFTERNOON AND EVENING HOURS WITH ANY THUNDERSTORMS THAT
REDEVELOP.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HALBLAUB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
953 AM CDT FRI JUN 14 2013
.UPDATE...
ISSUED AT 952 AM CDT FRI JUN 14 2013
OFF TO A BIT OF SLOW START DUE TO MONITORING RADAR THRU 830 AM.
THERE WERE A COUPLE OF NEAR-SVR STORMS THAT TRACKED FROM NEAR
HANSEN E ALONG THE HAMILTON-CLAY COUNTY LINE. WE SAW 50 DBZ UP TO
32K FT.
THE MRNG SHWRS/TSTMS WERE WARM FRONT GENERATED. THE HEAT WILL NOW
FOLLOW.
FCST HOURLY TEMPS WERE RUNNING WAY TOO WARM IN THE RAIN-COOLED
AREAS. SO SOME MAJOR ADJUSTMENTS HAVE BEEN MADE. CLEARING IS
HEADING E PER VIS SAT SO TEMPS SHOULD ROCKET UP. ALSO ADJUSTED
POPS AS SHWRS/TSTMS HAVE NEARLY CLEARED THE FCST AREA. POPS WERE
ALSO BLENDED WITH MULTIPLE HI-RES MODELS FROM 23Z-06Z TO COVER
TSTMS EXPECTED TO ERUPT.
FURTHER EVALUATION OF THE SITUATION WILL BE ON-GOING AND WE`LL
PROBABLY HAVE MORE IN AN AFD LATER THIS MRNG. 12Z SOUNDINGS ARE
SURPRISINGLY MOIST UP TO 850 MB. HOWEVER...WITH HIGHS OF 94-104F
AT 5 PM...SFC TEMP/DWPT SPREADS WILL STILL RESULT IN SUBSTANTIAL
DRYING BELOW CLOUD BASES THAT DEVELOP.
BASED ON BEST-VERIFYING HIGH TEMP GUIDANCE WE WILL PROBABLY BE
RAISING HIGH TEMPS SEVERAL DEGS IN THE TRI-CITIES AREA PENDING
FURTHER EVALUATION BEFORE NOON.
SLGT RISK CONTINUES FOR LATE THIS AFTN-EVNG.
PLEASE FOLLOW LATEST UPDATES FROM THE SPC VIA THEIR OUTLOOKS AND
MESOSCALE DISCUSSIONS...AND ALL FUTURE STATEMENTS/WATCHES/WARNINGS
FROM THIS OFFICE.
SKYWARN: BE ALERT FOR ACTIVATION IN THE 21Z-00Z TIME FRAME.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 413 AM CDT FRI JUN 14 2013
THE PRIMARY FORECAST CONCERN CENTERS AROUND THE CHANCE OF
THUNDERSTORMS EARLY THIS MORNING AND THEN AGAIN LATER THIS
AFTERNOON. SOME THUNDERSTORMS LATE THIS AFTERNOON AND EVENING WILL
LIKELY BE SEVERE.
THE FIRST ROUND OF THUNDERSTORMS HAVE BEEN WEAKENING AS THEY TRACK
EAST. THE HRRR SEEMS TO HAVE A GOOD HANDLE ON THESE STORMS AND
TRACKS THEM ALL THE WAY ACROSS OUR FORECAST AREA GENERALLY ALONG
THE INTERSTATE 80/HWY 6 CORRIDOR. CURRENT EXPECTATION IS THAT ALL
OF THESE THUNDERSTORMS WILL HAVE EITHER DECAYED OR BE EAST OF OUR
FORECAST AREA BY MID MORNING WITH DRY CONDITIONS FROM LATE
MORNING THROUGH MID AFTERNOON. THE HIGH CIRRUS LEFT OVER FROM THE
MORNING THUNDERSTORMS WILL THIN AND WE SHOULD SEE A GOOD DEAL OF
SUNSHINE TODAY HELPING TEMPERATURES SKY ROCKET. AN INCREASING
SOUTH WIND IN THE WARM SECTOR TODAY...WHICH WILL INCLUDE ALL OF
OUR FORECAST AREA EXCEPT MAYBE OUR FAR NORTHERN ZONES WILL ALSO
HELP TO GIVE TEMPERATURES A BOOST. EXPECT AFTERNOON HIGHS TO RANGE
FROM AROUND 90 IN OUR FAR NORTH AROUND ORD TO OVER 100 ACROSS MUCH
OF NORTH CENTRAL KANSAS.
THERE IS GOOD FORECAST MODEL AGREEMENT THAT AFTERNOON
THUNDERSTORMS WILL EVENTUALLY OVERCOME AN ELEVATED CAP
AND INITIATE ALONG A SFC FRONT THAT WILL STRETCH FROM NORTHEAST
NEBRASKA INTO SOUTH CENTRAL NEBRASKA AND NORTHWEST KANSAS. MLCAPE
VALUES ALONG THE FRONT WILL RANGE FROM 2000 TO 4000 J/KG MAKING
FOR A VERY UNSTABLE ATMOSPHERE. 0-6KM WIND SHEAR WILL BE MORE
MARGINAL AT 25 TO 35 KTS. THE COMBINATION OF STRONG
INSTABILITY...AT LEAST MARGINAL SHEAR...AND A FRONTAL BOUNDARY
SHOULD BE MORE THAN SUFFICIENT TO ALLOW FOR SEVERAL SEVERE
THUNDERSTORMS ACROSS OUR FORECAST AREA LATE THIS AFTERNOON AND
EVENING. EXPECT INITIATION WILL LIKELY BE AFTER 4 PM WITH THE
GREATEST SEVERE WEATHER THREAT IN THE 5 PM TO 10 PM TIME FRAME.
REDEVELOPMENT AND POSSIBLE TRAINING OF THUNDERSTORMS ALONG THE
FRONT WILL BE POSSIBLE LEADING TO LOCALIZED HEAVY RAIN. THE
HIGHEST CHANCE OF THUNDERSTORMS WILL GENERALLY BE NEAR HIGHWAY 30
FROM MERRICK COUNTY DOWN INTO GRAND ISLAND AND KEARNEY...AND THEN
SOUTHWEST INTO GOSPER AND FURNAS COUNTY. THE CHANCE OF
THUNDERSTORMS WILL DECREASE PRETTY FAST AS YOU HEAD SOUTHEAST OF
THIS CORRIDOR INTO NORTH CENTRAL KANSAS. THE PRIMARY SEVERE
WEATHER THREATS WILL BE LARGE HAIL TO THE SIZE OF GOLFBALLS AND
WIND GUSTS TO 70 MPH. WIND IS A BIG CONCERN DUE TO THE INVERTED V
FORECAST SOUNDING AND STEEP LAPSE RATES ALONG WITH THE OBVIOUSLY
HIGH CAPE. THE TORNADO THREAT WILL BE LIMITED DUE TO GENERALLY
WEAK LOW LEVEL SHEAR AND HIGHER LCL HEIGHTS. THE LIMITED TORNADO
THREAT WILL BE ACROSS OUR NORTHEASTERN CWA PRIMARY FOR THE KEARNEY
AND GRAND ISLAND AREAS AND POINTS NORTHEAST WHERE LCL HEIGHTS WILL
BE THE LOWEST AND THERE MIGHT BE SOME BACKING OF THE SFC WIND BY
EARLY EVENING...BUT AGAIN THIS IS ONLY A LIMITED THREAT WITH THE
PRIMARY THREATS TODAY BEING BIG HAIL AND STRONG THUNDERSTORM
WINDS.
THE CONVECTION WILL SLOWLY PUSH EAST TONIGHT AND AREAS ALONG AND
NORTH OF HIGHWAY 6 MAY ALSO SEE SOME ADDITIONAL THUNDERSTORM
REDEVELOPMENT DURING THE LATE EVENING HOURS AS THE LOW LEVEL JET
STRENGTHENS AND NOSES INTO OUR NEBRASKA ZONES.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 413 AM CDT FRI JUN 14 2013
MAIN FORECAST CONCERNS WILL BE CHANCES FOR THUNDERSTORMS AND
TEMPERATURES.
AN ACTIVE WEATHER PATTERN WILL BE FOUND ACROSS THE AREA THROUGH THIS
PERIOD. MODELS ARE SIMILAR IN THE MAIN FEATURES WITH SUBTLE
DIFFERENCES IN THE FINER DETAILS. SEVERAL UPPER LEVEL LOWS MOVE
THROUGH THE AREA DURING THE PERIOD AND EACH HAS THE POTENTIAL FOR
SOME THUNDERSTORMS. WITH THIS IN MIND THERE ARE CHANCES FOR
THUNDERSTORMS NEARLY EVERY PERIOD FOR PORTIONS OF THE AREA.
THE FIRST UPPER LEVEL LOW MOVES THROUGH THE AREA SATURDAY.
THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG A NEARLY STATIONARY
FRONT. THE QUESTION IS WHERE THIS FRONT WILL BE AND WHEN THE
THUNDERSTORMS DEVELOP. MODELS ARE SIMILAR THAT IT IS DRAPED ACROSS
THE CENTRAL TO SOUTHERN PART OF THE FORECAST AREA. HAVE KEPT CHANCES
ACROSS THE AREA WITH THUNDERSTORMS ALONG THE FRONT. THUNDERSTORM
CHANCES CONTINUE INTO SATURDAY NIGHT AS ANOTHER UPPER LEVEL WAVE
MOVES INTO THE AREA SATURDAY NIGHT AND THUNDERSTORMS ON THE HIGH
PLAINS START TO MOVE INTO THE AREA LATE SATURDAY NIGHT. THE NEXT
WAVE AFFECTS THE AREA SUNDAY AND SUNDAY NIGHT. THE BEST CHANCE FOR
THUNDERSTORMS WITH THIS ROUND WILL BE SUNDAY NIGHT IN THE SOUTHERN
PART OF THE FORECAST AREA.
THERE IS A BREAK ON MONDAY AS A SURFACE HIGH PRESSURE SYSTEM PUSHES
INTO THE AREA. THE BREAK IS SHORT LIVED FOR PORTIONS OF THE AREA.
ANOTHER UPPER LEVEL WAVE STARTS TO AFFECT THE CENTRAL HIGH PLAINS
MONDAY NIGHT THROUGH TUESDAY NIGHT...BUT WITH AN UPPER LEVEL RIDGE
ACROSS THE AREA AND THE SURFACE HIGH MOVING TO THE EAST THE STORMS
SHOULD BE MAINLY IN THE WESTERN PART OF THE FORECAST AREA.
WEDNESDAY THROUGH THURSDAY A SERIES OF UPPER LEVEL WAVES MOVE
THROUGH THE AREA AND BRING CHANCES FOR THUNDERSTORMS TO THE FORECAST
AREA AGAIN. MODELS HAVE A FEW DIFFERENCES IN THE TIMING OF THE
PRECIPITATION.
TEMPERATURES THROUGH THE PERIOD WILL BE MOSTLY IN THE 80S WITH A
LITTLE VARIATION UP AND DOWN THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 556 AM CDT FRI JUN 14 2013
SHOWERS AND THUNDERSTORMS WILL TRACK THROUGH KGRI EARLY THIS
MORNING WITH DRY WEATHER EXPECTED BY LATE MORNING THROUGH EARLY
AFTERNOON. THE FRONT WILL SINK TO AROUND KGRI BY MID AFTERNOON AND
THEN STALL OUT RESULTING IN FAIRLY LIGHT AND SHIFTY WINDS. WILL
STILL HAVE TO WATCH OUT FOR GUSTY THUNDERSTORM WINDS DURING THE
LATE AFTERNOON AND EVENING HOURS WITH ANY THUNDERSTORMS THAT
REDEVELOP.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HALBLAUB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
951 AM CDT FRI JUN 14 2013
.DISCUSSION...
MADE A FEW UDPATES FOR ONGOING MORNING TRENDS. CONVECTION IS
SLIDING EASTWARD OUT OF WESTERN IOWA...AND AREA OF LIGHT SHOWERS
ALONG THE I-80 CORRIDOR BETWEEN SEWARD AND LINCOLN IS DISSIPATING.
HOWEVER...A NEW LINE OF SHOWERS AND ISOLATED THUNDER HAS CROPPED
UP FROM ALBION TO YANKTON. HAVE ADJUSTED POPS FOR THESE
TRENDS...AND DO EXPECT ACTIVITY TO FADE/MOVE OUT THROUGH THE
REMAINDER OF THE MORNING HOURS...WITH THUNDERSTORMS DEVELOPING
AGAIN LATER THIS AFTERNOON...AND A WINDOW OF DRY WEATHER BETWEEN.
MAYES
&&
.PREV DISCUSSION... /ISSUED 714 AM CDT FRI JUN 14 2013/
AVIATION...
12Z TAFS FOR KOMA...KLNK...KOFK.
VFR CEILINGS ARE FORECAST ACROSS MUCH OF THE AREA DURING THE
DAY...EXCEPT IN THE VICINITY OF THUNDERSTORMS WHERE CEILINGS CAN
BE EXPECTED TO BE MVFR. SOUTHERLY WINDS ARE FORECAST TO BECOME
GUSTY BY 18Z WITH GUSTS AS HIGH AS 25 KT. SHRA OVER THE FORECAST
AREA SHOULD DIMINISH BY MID MORNING AND THEN TSRA IS EXPECTED TO
DEVELOP...ESPECIALLY AFTER 21Z.
SMITH
PREV DISCUSSION... /ISSUED 340 AM CDT FRI JUN 14 2013/
DISCUSSION...
.MAIN FORECAST CONCERN IS CONVECTION THIS MORNING...THEN AGAIN
THIS AFTERNOON AND TONIGHT...
LATEST WATER VAPOR IMAGERY AND RAP 500MB ANALYSIS SHOW A TROUGH AXIS
EXTENDING FROM LOW PRESSURE IN ALBERTA SOUTHWARD TOWARD NORTHERN
NEVADA. DOWNSTREAM...A HIGH PRESSURE RIDGE AXIS EXTENDS FROM THE
SOUTHERN PLAINS INTO CENTRAL MANITOBA. AN EMBEDDED WEAK SHORTWAVE
CONTINUES TO MOVE UP THE BACKSIDE OF THE RIDGE AND INTO CENTRAL
NEBRASKA. WIDELY SCATTERED THUNDERSTORMS CONTINUE IN ADVANCE OF
THIS SHORTWAVE AND THESE ARE SLOWLY MOVING EAST-NORTHEAST. MOST
LIKELY SCENARIO TO PLAY OUT SEEMS TO BE WHAT THE HRRR AND RAP
HAVE BEEN INDICATING AND THAT IS FOR THE CONVECTION ASSOCIATED
WITH THE ABOVE MENTIONED SHORTWAVE TO CONTINUE TO CLUSTER TOGETHER AND
DRIFT EAST ACROSS THE CWA THROUGH THE MORNING WHERE STRONG
ISENTROPIC UPGLIDE RESIDES. SOME OF THESE MAY CONTAIN MARGINALLY
SEVERE HAIL...AIDED BY A VEERED 35-45KT LOW LEVEL JET.
CLOUD COVER FROM MORNING CONVECTIVE ACTIVITY WILL LIKELY INHIBIT
STRONG HEATING INITIALLY. AS HIGH PLAINS SFC LOW PRESSURE SLIDES
EAST TODAY...A WARM FRONT WILL EXTEND WEST TO EAST ACROSS THE
FORECAST AREA BRINGING A RAPID WARM UP TO THE AREA THIS
AFTERNOON...ESPECIALLY IN OUR SOUTH. IN ADDITION...SFC DEWPOINTS
ARE PROGGED TO RISE INTO THE LOWER 70S BY AFTERNOON WHICH MAY BE A
BIT HIGH AND PUSHES FORECASTED SFC BASED CAPE VALUES INTO THE 4000
J/KG RANGE. WITH AN INCREASING SOUTHWEST LOW LEVEL JET EARLY IN
THE EVENING AIDING TSTMS...THINK BUSIEST TIMEFRAME IN TERMS OF ANY
SEVERE STORMS WILL BE FROM ABOUT 23Z-03Z NEAR THE SFC BOUNDARY.
THIS WILL MOST LIKELY LINGER INTO THE OVERNIGHT HOURS AS A
POSSIBLE MCS AS THE BOUNDARY REMAINS IN THE AREA. ALL THIS LIMITED
OF COURSE BY CAPPING INVERSION...ESPECIALLY THIS AFTERNOON.
WILL CONTINUE TO CARRY POPS THROUGH THE WEEKEND AS THE BOUNDARY
REMAINS OVER THE AREA ALTHOUGH DO NOT THINK WE WILL HAVE A
CONTINUOUS PERIOD OF THUNDERSTORMS THROUGHOUT THE ENTIRE WEEKEND.
WITH WESTERLY MID LEVEL FLOW...HIGHER POPS ARE WARRANTED WITH
THIS BOUNDARY EXTENDING OVER THE AREA.
NO CHANGES INTO THE LATER PERIODS WITH DRIER WEATHER ON TAP FOR
MONDAY AND TUESDAY AND A BIT MORE ACTIVE MID TO LATE WEEK.
KERN
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
714 AM CDT FRI JUN 14 2013
.AVIATION...
12Z TAFS FOR KOMA...KLNK...KOFK.
VFR CEILINGS ARE FORECAST ACROSS MUCH OF THE AREA DURING THE
DAY...EXCEPT IN THE VICINITY OF THUNDERSTORMS WHERE CEILINGS CAN
BE EXPECTED TO BE MVFR. SOUTHERLY WINDS ARE FORECAST TO BECOME
GUSTY BY 18Z WITH GUSTS AS HIGH AS 25 KT. SHRA OVER THE FORECAST
AREA SHOULD DIMINISH BY MID MORNING AND THEN TSRA IS EXPECTED TO
DEVELOP...ESPECIALLY AFTER 21Z.
SMITH
&&
.PREV DISCUSSION... /ISSUED 340 AM CDT FRI JUN 14 2013/
DISCUSSION...
..MAIN FORECAST CONCERN IS CONVECTION THIS MORNING...THEN AGAIN
THIS AFTERNOON AND TONIGHT...
LATEST WATER VAPOR IMAGERY AND RAP 500MB ANALYSIS SHOW A TROUGH AXIS
EXTENDING FROM LOW PRESSURE IN ALBERTA SOUTHWARD TOWARD NORTHERN
NEVADA. DOWNSTREAM...A HIGH PRESSURE RIDGE AXIS EXTENDS FROM THE
SOUTHERN PLAINS INTO CENTRAL MANITOBA. AN EMBEDDED WEAK SHORTWAVE
CONTINUES TO MOVE UP THE BACKSIDE OF THE RIDGE AND INTO CENTRAL
NEBRASKA. WIDELY SCATTERED THUNDERSTORMS CONTINUE IN ADVANCE OF
THIS SHORTWAVE AND THESE ARE SLOWLY MOVING EAST-NORTHEAST. MOST
LIKELY SCENARIO TO PLAY OUT SEEMS TO BE WHAT THE HRRR AND RAP
HAVE BEEN INDICATING AND THAT IS FOR THE CONVECTION ASSOCIATED
WITH THE ABOVE MENTIONED SHORTWAVE TO CONTINUE TO CLUSTER TOGETHER AND
DRIFT EAST ACROSS THE CWA THROUGH THE MORNING WHERE STRONG
ISENTROPIC UPGLIDE RESIDES. SOME OF THESE MAY CONTAIN MARGINALLY
SEVERE HAIL...AIDED BY A VEERED 35-45KT LOW LEVEL JET.
CLOUD COVER FROM MORNING CONVECTIVE ACTIVITY WILL LIKELY INHIBIT
STRONG HEATING INITIALLY. AS HIGH PLAINS SFC LOW PRESSURE SLIDES
EAST TODAY...A WARM FRONT WILL EXTEND WEST TO EAST ACROSS THE
FORECAST AREA BRINGING A RAPID WARM UP TO THE AREA THIS
AFTERNOON...ESPECIALLY IN OUR SOUTH. IN ADDITION...SFC DEWPOINTS
ARE PROGGED TO RISE INTO THE LOWER 70S BY AFTERNOON WHICH MAY BE A
BIT HIGH AND PUSHES FORECASTED SFC BASED CAPE VALUES INTO THE 4000
J/KG RANGE. WITH AN INCREASING SOUTHWEST LOW LEVEL JET EARLY IN
THE EVENING AIDING TSTMS...THINK BUSIEST TIMEFRAME IN TERMS OF ANY
SEVERE STORMS WILL BE FROM ABOUT 23Z-03Z NEAR THE SFC BOUNDARY.
THIS WILL MOST LIKELY LINGER INTO THE OVERNIGHT HOURS AS A
POSSIBLE MCS AS THE BOUNDARY REMAINS IN THE AREA. ALL THIS LIMITED
OF COURSE BY CAPPING INVERSION...ESPECIALLY THIS AFTERNOON.
WILL CONTINUE TO CARRY POPS THROUGH THE WEEKEND AS THE BOUNDARY
REMAINS OVER THE AREA ALTHOUGH DO NOT THINK WE WILL HAVE A
CONTINUOUS PERIOD OF THUNDERSTORMS THROUGHOUT THE ENTIRE WEEKEND.
WITH WESTERLY MID LEVEL FLOW...HIGHER POPS ARE WARRANTED WITH
THIS BOUNDARY EXTENDING OVER THE AREA.
NO CHANGES INTO THE LATER PERIODS WITH DRIER WEATHER ON TAP FOR
MONDAY AND TUESDAY AND A BIT MORE ACTIVE MID TO LATE WEEK.
KERN
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION
NWS HASTINGS NE
605 AM CDT FRI JUN 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 413 AM CDT FRI JUN 14 2013
THE PRIMARY FORECAST CONCERN CENTERS AROUND THE CHANCE OF
THUNDERSTORMS EARLY THIS MORNING AND THEN AGAIN LATER THIS
AFTERNOON. SOME THUNDERSTORMS LATE THIS AFTERNOON AND EVENING WILL
LIKELY BE SEVERE.
THE FIRST ROUND OF THUNDERSTORMS HAVE BEEN WEAKENING AS THEY TRACK
EAST. THE HRRR SEEMS TO HAVE A GOOD HANDLE ON THESE STORMS AND
TRACKS THEM ALL THE WAY ACROSS OUR FORECAST AREA GENERALLY ALONG
THE INTERSTATE 80/HWY 6 CORRIDOR. CURRENT EXPECTATION IS THAT ALL
OF THESE THUNDERSTORMS WILL HAVE EITHER DECAYED OR BE EAST OF OUR
FORECAST AREA BY MID MORNING WITH DRY CONDITIONS FROM LATE
MORNING THROUGH MID AFTERNOON. THE HIGH CIRRUS LEFT OVER FROM THE
MORNING THUNDERSTORMS WILL THIN AND WE SHOULD SEE A GOOD DEAL OF
SUNSHINE TODAY HELPING TEMPERATURES SKY ROCKET. AN INCREASING
SOUTH WIND IN THE WARM SECTOR TODAY...WHICH WILL INCLUDE ALL OF
OUR FORECAST AREA EXCEPT MAYBE OUR FAR NORTHERN ZONES WILL ALSO
HELP TO GIVE TEMPERATURES A BOOST. EXPECT AFTERNOON HIGHS TO RANGE
FROM AROUND 90 IN OUR FAR NORTH AROUND ORD TO OVER 100 ACROSS MUCH
OF NORTH CENTRAL KANSAS.
THERE IS GOOD FORECAST MODEL AGREEMENT THAT AFTERNOON
THUNDERSTORMS WILL EVENTUALLY OVERCOME AN ELEVATED CAP
AND INITIATE ALONG A SFC FRONT THAT WILL STRETCH FROM NORTHEAST
NEBRASKA INTO SOUTH CENTRAL NEBRASKA AND NORTHWEST KANSAS. MLCAPE
VALUES ALONG THE FRONT WILL RANGE FROM 2000 TO 4000 J/KG MAKING
FOR A VERY UNSTABLE ATMOSPHERE. 0-6KM WIND SHEAR WILL BE MORE
MARGINAL AT 25 TO 35 KTS. THE COMBINATION OF STRONG
INSTABILITY...AT LEAST MARGINAL SHEAR...AND A FRONTAL BOUNDARY
SHOULD BE MORE THAN SUFFICIENT TO ALLOW FOR SEVERAL SEVERE
THUNDERSTORMS ACROSS OUR FORECAST AREA LATE THIS AFTERNOON AND
EVENING. EXPECT INITIATION WILL LIKELY BE AFTER 4 PM WITH THE
GREATEST SEVERE WEATHER THREAT IN THE 5 PM TO 10 PM TIME FRAME.
REDEVELOPMENT AND POSSIBLE TRAINING OF THUNDERSTORMS ALONG THE
FRONT WILL BE POSSIBLE LEADING TO LOCALIZED HEAVY RAIN. THE
HIGHEST CHANCE OF THUNDERSTORMS WILL GENERALLY BE NEAR HIGHWAY 30
FROM MERRICK COUNTY DOWN INTO GRAND ISLAND AND KEARNEY...AND THEN
SOUTHWEST INTO GOSPER AND FURNAS COUNTY. THE CHANCE OF
THUNDERSTORMS WILL DECREASE PRETTY FAST AS YOU HEAD SOUTHEAST OF
THIS CORRIDOR INTO NORTH CENTRAL KANSAS. THE PRIMARY SEVERE
WEATHER THREATS WILL BE LARGE HAIL TO THE SIZE OF GOLFBALLS AND
WIND GUSTS TO 70 MPH. WIND IS A BIG CONCERN DUE TO THE INVERTED V
FORECAST SOUNDING AND STEEP LAPSE RATES ALONG WITH THE OBVIOUSLY
HIGH CAPE. THE TORNADO THREAT WILL BE LIMITED DUE TO GENERALLY
WEAK LOW LEVEL SHEAR AND HIGHER LCL HEIGHTS. THE LIMITED TORNADO
THREAT WILL BE ACROSS OUR NORTHEASTERN CWA PRIMARY FOR THE KEARNEY
AND GRAND ISLAND AREAS AND POINTS NORTHEAST WHERE LCL HEIGHTS WILL
BE THE LOWEST AND THERE MIGHT BE SOME BACKING OF THE SFC WIND BY
EARLY EVENING...BUT AGAIN THIS IS ONLY A LIMITED THREAT WITH THE
PRIMARY THREATS TODAY BEING BIG HAIL AND STRONG THUNDERSTORM
WINDS.
THE CONVECTION WILL SLOWLY PUSH EAST TONIGHT AND AREAS ALONG AND
NORTH OF HIGHWAY 6 MAY ALSO SEE SOME ADDITIONAL THUNDERSTORM
REDEVELOPMENT DURING THE LATE EVENING HOURS AS THE LOW LEVEL JET
STRENGTHENS AND NOSES INTO OUR NEBRASKA ZONES.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 413 AM CDT FRI JUN 14 2013
MAIN FORECAST CONCERNS WILL BE CHANCES FOR THUNDERSTORMS AND
TEMPERATURES.
AN ACTIVE WEATHER PATTERN WILL BE FOUND ACROSS THE AREA THROUGH THIS
PERIOD. MODELS ARE SIMILAR IN THE MAIN FEATURES WITH SUBTLE
DIFFERENCES IN THE FINER DETAILS. SEVERAL UPPER LEVEL LOWS MOVE
THROUGH THE AREA DURING THE PERIOD AND EACH HAS THE POTENTIAL FOR
SOME THUNDERSTORMS. WITH THIS IN MIND THERE ARE CHANCES FOR
THUNDERSTORMS NEARLY EVERY PERIOD FOR PORTIONS OF THE AREA.
THE FIRST UPPER LEVEL LOW MOVES THROUGH THE AREA SATURDAY.
THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG A NEARLY STATIONARY
FRONT. THE QUESTION IS WHERE THIS FRONT WILL BE AND WHEN THE
THUNDERSTORMS DEVELOP. MODELS ARE SIMILAR THAT IT IS DRAPED ACROSS
THE CENTRAL TO SOUTHERN PART OF THE FORECAST AREA. HAVE KEPT CHANCES
ACROSS THE AREA WITH THUNDERSTORMS ALONG THE FRONT. THUNDERSTORM
CHANCES CONTINUE INTO SATURDAY NIGHT AS ANOTHER UPPER LEVEL WAVE
MOVES INTO THE AREA SATURDAY NIGHT AND THUNDERSTORMS ON THE HIGH
PLAINS START TO MOVE INTO THE AREA LATE SATURDAY NIGHT. THE NEXT
WAVE AFFECTS THE AREA SUNDAY AND SUNDAY NIGHT. THE BEST CHANCE FOR
THUNDERSTORMS WITH THIS ROUND WILL BE SUNDAY NIGHT IN THE SOUTHERN
PART OF THE FORECAST AREA.
THERE IS A BREAK ON MONDAY AS A SURFACE HIGH PRESSURE SYSTEM PUSHES
INTO THE AREA. THE BREAK IS SHORT LIVED FOR PORTIONS OF THE AREA.
ANOTHER UPPER LEVEL WAVE STARTS TO AFFECT THE CENTRAL HIGH PLAINS
MONDAY NIGHT THROUGH TUESDAY NIGHT...BUT WITH AN UPPER LEVEL RIDGE
ACROSS THE AREA AND THE SURFACE HIGH MOVING TO THE EAST THE STORMS
SHOULD BE MAINLY IN THE WESTERN PART OF THE FORECAST AREA.
WEDNESDAY THROUGH THURSDAY A SERIES OF UPPER LEVEL WAVES MOVE
THROUGH THE AREA AND BRING CHANCES FOR THUNDERSTORMS TO THE FORECAST
AREA AGAIN. MODELS HAVE A FEW DIFFERENCES IN THE TIMING OF THE
PRECIPITATION.
TEMPERATURES THROUGH THE PERIOD WILL BE MOSTLY IN THE 80S WITH A
LITTLE VARIATION UP AND DOWN THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 556 AM CDT FRI JUN 14 2013
SHOWERS AND THUNDERSTORMS WILL TRACK THROUGH KGRI EARLY THIS
MORNING WITH DRY WEATHER EXPECTED BY LATE MORNING THROUGH EARLY
AFTERNOON. THE FRONT WILL SINK TO AROUND KGRI BY MID AFTERNOON AND
THEN STALL OUT RESULTING IN FAIRLY LIGHT AND SHIFTY WINDS. WILL
STILL HAVE TO WATCH OUT FOR GUSTY THUNDERSTORM WINDS DURING THE
LATE AFTERNOON AND EVENING HOURS WITH ANY THUNDERSTORMS THAT
REDEVELOP.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HASTINGS NE
509 AM CDT FRI JUN 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 413 AM CDT FRI JUN 14 2013
THE PRIMARY FORECAST CONCERN CENTERS AROUND THE CHANCE OF
THUNDERSTORMS EARLY THIS MORNING AND THEN AGAIN LATER THIS
AFTERNOON. SOME THUNDERSTORMS LATE THIS AFTERNOON AND EVENING WILL
LIKELY BE SEVERE.
THE FIRST ROUND OF THUNDERSTORMS HAVE BEEN WEAKENING AS THEY TRACK
EAST. THE HRRR SEEMS TO HAVE A GOOD HANDLE ON THESE STORMS AND
TRACKS THEM ALL THE WAY ACROSS OUR FORECAST AREA GENERALLY ALONG
THE INTERSTATE 80/HWY 6 CORRIDOR. CURRENT EXPECTATION IS THAT ALL
OF THESE THUNDERSTORMS WILL HAVE EITHER DECAYED OR BE EAST OF OUR
FORECAST AREA BY MID MORNING WITH DRY CONDITIONS FROM LATE
MORNING THROUGH MID AFTERNOON. THE HIGH CIRRUS LEFT OVER FROM THE
MORNING THUNDERSTORMS WILL THIN AND WE SHOULD SEE A GOOD DEAL OF
SUNSHINE TODAY HELPING TEMPERATURES SKY ROCKET. AN INCREASING
SOUTH WIND IN THE WARM SECTOR TODAY...WHICH WILL INCLUDE ALL OF
OUR FORECAST AREA EXCEPT MAYBE OUR FAR NORTHERN ZONES WILL ALSO
HELP TO GIVE TEMPERATURES A BOOST. EXPECT AFTERNOON HIGHS TO RANGE
FROM AROUND 90 IN OUR FAR NORTH AROUND ORD TO OVER 100 ACROSS MUCH
OF NORTH CENTRAL KANSAS.
THERE IS GOOD FORECAST MODEL AGREEMENT THAT AFTERNOON
THUNDERSTORMS WILL EVENTUALLY OVERCOME AN ELEVATED CAP
AND INITIATE ALONG A SFC FRONT THAT WILL STRETCH FROM NORTHEAST
NEBRASKA INTO SOUTH CENTRAL NEBRASKA AND NORTHWEST KANSAS. MLCAPE
VALUES ALONG THE FRONT WILL RANGE FROM 2000 TO 4000 J/KG MAKING
FOR A VERY UNSTABLE ATMOSPHERE. 0-6KM WIND SHEAR WILL BE MORE
MARGINAL AT 25 TO 35 KTS. THE COMBINATION OF STRONG
INSTABILITY...AT LEAST MARGINAL SHEAR...AND A FRONTAL BOUNDARY
SHOULD BE MORE THAN SUFFICIENT TO ALLOW FOR SEVERAL SEVERE
THUNDERSTORMS ACROSS OUR FORECAST AREA LATE THIS AFTERNOON AND
EVENING. EXPECT INITIATION WILL LIKELY BE AFTER 4 PM WITH THE
GREATEST SEVERE WEATHER THREAT IN THE 5 PM TO 10 PM TIME FRAME.
REDEVELOPMENT AND POSSIBLE TRAINING OF THUNDERSTORMS ALONG THE
FRONT WILL BE POSSIBLE LEADING TO LOCALIZED HEAVY RAIN. THE
HIGHEST CHANCE OF THUNDERSTORMS WILL GENERALLY BE NEAR HIGHWAY 30
FROM MERRICK COUNTY DOWN INTO GRAND ISLAND AND KEARNEY...AND THEN
SOUTHWEST INTO GOSPER AND FURNAS COUNTY. THE CHANCE OF
THUNDERSTORMS WILL DECREASE PRETTY FAST AS YOU HEAD SOUTHEAST OF
THIS CORRIDOR INTO NORTH CENTRAL KANSAS. THE PRIMARY SEVERE
WEATHER THREATS WILL BE LARGE HAIL TO THE SIZE OF GOLFBALLS AND
WIND GUSTS TO 70 MPH. WIND IS A BIG CONCERN DUE TO THE INVERTED V
FORECAST SOUNDING AND STEEP LAPSE RATES ALONG WITH THE OBVIOUSLY
HIGH CAPE. THE TORNADO THREAT WILL BE LIMITED DUE TO GENERALLY
WEAK LOW LEVEL SHEAR AND HIGHER LCL HEIGHTS. THE LIMITED TORNADO
THREAT WILL BE ACROSS OUR NORTHEASTERN CWA PRIMARY FOR THE KEARNEY
AND GRAND ISLAND AREAS AND POINTS NORTHEAST WHERE LCL HEIGHTS WILL
BE THE LOWEST AND THERE MIGHT BE SOME BACKING OF THE SFC WIND BY
EARLY EVENING...BUT AGAIN THIS IS ONLY A LIMITED THREAT WITH THE
PRIMARY THREATS TODAY BEING BIG HAIL AND STRONG THUNDERSTORM
WINDS.
THE CONVECTION WILL SLOWLY PUSH EAST TONIGHT AND AREAS ALONG AND
NORTH OF HIGHWAY 6 MAY ALSO SEE SOME ADDITIONAL THUNDERSTORM
REDEVELOPMENT DURING THE LATE EVENING HOURS AS THE LOW LEVEL JET
STRENGTHENS AND NOSES INTO OUR NEBRASKA ZONES.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 413 AM CDT FRI JUN 14 2013
MAIN FORECAST CONCERNS WILL BE CHANCES FOR THUNDERSTORMS AND
TEMPERATURES.
AN ACTIVE WEATHER PATTERN WILL BE FOUND ACROSS THE AREA THROUGH THIS
PERIOD. MODELS ARE SIMILAR IN THE MAIN FEATURES WITH SUBTLE
DIFFERENCES IN THE FINER DETAILS. SEVERAL UPPER LEVEL LOWS MOVE
THROUGH THE AREA DURING THE PERIOD AND EACH HAS THE POTENTIAL FOR
SOME THUNDERSTORMS. WITH THIS IN MIND THERE ARE CHANCES FOR
THUNDERSTORMS NEARLY EVERY PERIOD FOR PORTIONS OF THE AREA.
THE FIRST UPPER LEVEL LOW MOVES THROUGH THE AREA SATURDAY.
THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG A NEARLY STATIONARY
FRONT. THE QUESTION IS WHERE THIS FRONT WILL BE AND WHEN THE
THUNDERSTORMS DEVELOP. MODELS ARE SIMILAR THAT IT IS DRAPED ACROSS
THE CENTRAL TO SOUTHERN PART OF THE FORECAST AREA. HAVE KEPT CHANCES
ACROSS THE AREA WITH THUNDERSTORMS ALONG THE FRONT. THUNDERSTORM
CHANCES CONTINUE INTO SATURDAY NIGHT AS ANOTHER UPPER LEVEL WAVE
MOVES INTO THE AREA SATURDAY NIGHT AND THUNDERSTORMS ON THE HIGH
PLAINS START TO MOVE INTO THE AREA LATE SATURDAY NIGHT. THE NEXT
WAVE AFFECTS THE AREA SUNDAY AND SUNDAY NIGHT. THE BEST CHANCE FOR
THUNDERSTORMS WITH THIS ROUND WILL BE SUNDAY NIGHT IN THE SOUTHERN
PART OF THE FORECAST AREA.
THERE IS A BREAK ON MONDAY AS A SURFACE HIGH PRESSURE SYSTEM PUSHES
INTO THE AREA. THE BREAK IS SHORT LIVED FOR PORTIONS OF THE AREA.
ANOTHER UPPER LEVEL WAVE STARTS TO AFFECT THE CENTRAL HIGH PLAINS
MONDAY NIGHT THROUGH TUESDAY NIGHT...BUT WITH AN UPPER LEVEL RIDGE
ACROSS THE AREA AND THE SURFACE HIGH MOVING TO THE EAST THE STORMS
SHOULD BE MAINLY IN THE WESTERN PART OF THE FORECAST AREA.
WEDNESDAY THROUGH THURSDAY A SERIES OF UPPER LEVEL WAVES MOVE
THROUGH THE AREA AND BRING CHANCES FOR THUNDERSTORMS TO THE FORECAST
AREA AGAIN. MODELS HAVE A FEW DIFFERENCES IN THE TIMING OF THE
PRECIPITATION.
TEMPERATURES THROUGH THE PERIOD WILL BE MOSTLY IN THE 80S WITH A
LITTLE VARIATION UP AND DOWN THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1239 AM CDT FRI JUN 14 2013
THUNDERSTORMS TO THE WEST OF GRAND ISLAND CONTINUE TO DIE AS THEY
SLOWLY MOVE EAST. CAN NOT RULE OUT A FEW LIGHT RAIN SHOWERS EARLY
THIS MORNING...BUT CHANCES ARE LOW ENOUGH TO KEEP IT OUT OF THE
TAF FOR NOW. THE BETTER CHANCE FOR THUNDERSTORMS WILL BE LATE
AFTERNOON AND LASTING THROUGH THE EVENING AS A SFC FRONT STALLS
OUT RIGHT OVER KGRI. THE WIND WILL PICK UP AFTER SUNRISE THIS
MORNING AND THEN DIE DOWN THIS EVENING AS THE FRONT STALLS
OVERHEAD.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
340 AM CDT FRI JUN 14 2013
.DISCUSSION...
...MAIN FORECAST CONCERN IS CONVECTION THIS MORNING...THEN AGAIN
THIS AFTERNOON AND TONIGHT...
LATEST WATER VAPOR IMAGERY AND RAP 500MB ANALYSIS SHOW A TROUGH AXIS
EXTENDING FROM LOW PRESSURE IN ALBERTA SOUTHWARD TOWARD NORTHERN
NEVADA. DOWNSTREAM...A HIGH PRESSURE RIDGE AXIS EXTENDS FROM THE
SOUTHERN PLAINS INTO CENTRAL MANITOBA. AN EMBEDDED WEAK SHORTWAVE
CONTINUES TO MOVE UP THE BACKSIDE OF THE RIDGE AND INTO CENTRAL
NEBRASKA. WIDELY SCATTERED THUNDERSTORMS CONTINUE IN ADVANCE OF
THIS SHORTWAVE AND THESE ARE SLOWLY MOVING EAST-NORTHEAST. MOST
LIKELY SCENARIO TO PLAY OUT SEEMS TO BE WHAT THE HRRR AND RAP
HAVE BEEN INDICATING AND THAT IS FOR THE CONVECTION ASSOCIATED
WITH THE ABOVE MENTIONED SHORTWAVE TO CONTINUE TO CLUSTER TOGETHER AND
DRIFT EAST ACROSS THE CWA THROUGH THE MORNING WHERE STRONG
ISENTROPIC UPGLIDE RESIDES. SOME OF THESE MAY CONTAIN MARGINALLY
SEVERE HAIL...AIDED BY A VEERED 35-45KT LOW LEVEL JET.
CLOUD COVER FROM MORNING CONVECTIVE ACTIVITY WILL LIKELY INHIBIT
STRONG HEATING INITIALLY. AS HIGH PLAINS SFC LOW PRESSURE SLIDES
EAST TODAY...A WARM FRONT WILL EXTEND WEST TO EAST ACROSS THE
FORECAST AREA BRINGING A RAPID WARM UP TO THE AREA THIS
AFTERNOON...ESPECIALLY IN OUR SOUTH. IN ADDITION...SFC DEWPOINTS
ARE PROGGED TO RISE INTO THE LOWER 70S BY AFTERNOON WHICH MAY BE A
BIT HIGH AND PUSHES FORECASTED SFC BASED CAPE VALUES INTO THE 4000
J/KG RANGE. WITH AN INCREASING SOUTHWEST LOW LEVEL JET EARLY IN
THE EVENING AIDING TSTMS...THINK BUSIEST TIMEFRAME IN TERMS OF ANY
SEVERE STORMS WILL BE FROM ABOUT 23Z-03Z NEAR THE SFC BOUNDARY.
THIS WILL MOST LIKELY LINGER INTO THE OVERNIGHT HOURS AS A
POSSIBLE MCS AS THE BOUNDARY REMAINS IN THE AREA. ALL THIS LIMITED
OF COURSE BY CAPPING INVERSION...ESPECIALLY THIS AFTERNOON.
WILL CONTINUE TO CARRY POPS THROUGH THE WEEKEND AS THE BOUNDARY
REMAINS OVER THE AREA ALTHOUGH DO NOT THINK WE WILL HAVE A
CONTINUOUS PERIOD OF THUNDERSTORMS THROUGHOUT THE ENTIRE WEEKEND.
WITH WESTERLY MID LEVEL FLOW...HIGHER POPS ARE WARRANTED WITH
THIS BOUNDARY EXTENDING OVER THE AREA.
NO CHANGES INTO THE LATER PERIODS WITH DRIER WEATHER ON TAP FOR
MONDAY AND TUESDAY AND A BIT MORE ACTIVE MID TO LATE WEEK.
KERN
&&
.AVIATION...06Z TAFS FOR KOMA...KLNK...KOFK.
VFR CONDITIONS SHOULD OCCUR AT ALL THREE SITES OVERNIGHT. SOME
SHRA AND TSRA ARE EXPECTED TO DEVELOP OVER PARTS OF EASTERN
NEBRASKA BETWEEN ABOUT 10Z AND 12Z THEN AFFECT MAINLY KOFK AND
KOMA IN THE MORNING. CEILINGS WITH THIS ACTIVITY WOULD BE MAINLY
ABOVE 4000 FEET...BUT SOME MVFR CEILINGS AROUND 2500 FEET ARE
POSSIBLE. SOUTHERLY WINDS WILL INCREASE AND BECOME GUSTY BY MID
TO LATE MORNING.
TSRA SHOULD INCREASE OVER THE REGION MID TO LATE AFTN. INCLUDED A
PROB 30 GROUP FOR THIS AT KOFK...BUT LEFT OUT FOR KOMA AND KLNK
AT HIS TIME DUE TO UNCERTAINTY OF COVERAGE.
MILLER
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1150 PM CDT THU JUN 13 2013
.AVIATION...
06Z TAFS FOR KOMA...KLNK...KOFK.
VFR CONDITIONS SHOULD OCCUR AT ALL THREE SITES OVERNIGHT. SOME
SHRA AND TSRA ARE EXPECTED TO DEVELOP OVER PARTS OF EASTERN
NEBRASKA BETWEEN ABOUT 10Z AND 12Z THEN AFFECT MAINLY KOFK AND
KOMA IN THE MORNING. CEILINGS WITH THIS ACTIVITY WOULD BE MAINLY
ABOVE 4000 FEET...BUT SOME MVFR CEILINGS AROUND 2500 FEET ARE
POSSIBLE. SOUTHERLY WINDS WILL INCREASE AND BECOME GUSTY BY MID
TO LATE MORNING.
TSRA SHOULD INCREASE OVER THE REGION MID TO LATE AFTN. INCLUDED A
PROB 30 GROUP FOR THIS AT KOFK...BUT LEFT OUT FOR KOMA AND KLNK
AT HIS TIME DUE TO UNCERTAINTY OF COVERAGE.
MILLER
&&
.PREV DISCUSSION... /ISSUED 920 PM CDT THU JUN 13 2013/
UPDATE...
BAND OF PCPN THAT WAS MOVING THROUGH THE AREA THIS AFTERNOON AND
EARLY EVENING HAS MOVED EAST OF THE FORECAST AREA AS OF 9 PM SO
CLEANED UP ZFP WORDING FOR THAT. EXPECT THAT PCPN WILL PROBABLY
HOLD OFF MOST AREAS OVERNIGHT...BUT SOME CHANCE BY 3-4 AM CDT.
01Z HIGH RESOLUTION RAP AND 00Z NAM INDICATE THIS TREND. MADE A
FEW MINOR CHANGES TO POPS IN THE MORNING. OTHERWISE FEW IF ANY
CHANGES MADE BEYOND THE TONIGHT PERIOD.
MILLER
PREV DISCUSSION... /ISSUED 308 PM CDT THU JUN 13 2013/
DISCUSSION...
THUNDERSTORM COMPLEX...INITIALLY PROBABLY ROOTED NEAR 600 MB PER
LBF/OAX 12Z SOUNDINGS...CONTINUED WORKING INTO FORECAST AREA THIS
AFTERNOON DESPITE LACK OF LOW LEVEL JET/INSTABILITY SUPPORT. THIS
HIGHLIGHTS UNCERTAINTIES THAT WILL EXIST IN FINE-TUNING
THUNDERSTORM CHCS AND TIMES THROUGH THIS WEEKEND AND IS THE
PRIMARY FORECAST CONCERN.
CURRENT RADAR TRENDS/LATEST RAP FCST WOULD TAKE THIS AREA OF
CONVECTION OUT OF ERN ZONES BY AROUND 02Z WITH A PROBABLE PRECIP
LULL UNTIL CONVECTION DEVELOPING TO OUR WEST APPROACHES OR
DEVELOPS INTO ZONES LATER TONIGHT. MADE SOME ATTEMPTS AT
ADJUSTING HOURLY GRIDS TO REFLECT THIS TREND TONIGHT.
HOWEVER...AFTER THAT RELUCTANT TO REMOVE OR LOWER TOMORROW MORNING
POPS VERY MUCH...ESPECIALLY CNTRL/NE ZONES AS 00Z/12Z ECMWF AND
12Z GFS CONTINUED TO DEVELOP QPF OVER THE NERN FA IN 12-18Z PD.
SINCE THIS AREA WILL BE ON NOSE OF THE MOISTURE/INSTABILITY RETURN
NOTED BY STRONG H85 THETA E ADVECTION IN 12Z-15Z PERIOD PER
NAM...LEFT IN LIKELY MORNING POPS NERN ZONES. ALTHOUGH THERE COULD
BE A MIDDAY LULL IN THE ACTIVITY...THIS THETA ADVECTION INCREASES
AGAIN IN THE AFTERNOON. THUS CANNOT REALLY SAY WHETHER OR NOT
CONVECTION WILL COMPLETELY DIE OUT...WHICH HAS BEEN THE CASE TODAY
AND WAS A FEW DAYS AGO AS WELL. SFC BASED DWPT RETURN PER NAM/GFS
PROBABLY TOO HIGH THUS SFC BASED CAPE FORECAST ALSO TOO HIGH
FRIDAY...BUT WITH BOUNDARY IN AREA AND UPPER WAVE LIFTING INTO
NERN MT...SOME SEVERE THREAT WILL PROBABLY EXIST. HOWEVER...
COVERAGE PROBABLY DICTATED BY EFFECTIVENESS OF CAP WHICH WILL BE
TRYING TO BECOME ESTABLISHED...ESPECIALLY SRN ZONES...OR DEBRIS
CLOUDS/PCPN FROM ANY MORNING ACTIVITY NE. AT THIS TIME MADE
LITTLE/NO CHANCES TO MAX TEMPS WHICH WILL LIKELY NEED ADJUSTING AS
AMOUNT OF DEBRIS BECOMES APPARENT.
WITH BOUNDARY REMAINING OVER AREA SATURDAY AND POSSIBLY SUNDAY...
AND CNTRL PLAINS CONTINUING ON SRN END OF WESTERLIES OF SRN
CANADIAN LOW...MODESTLY HIGH POPS WARRANTED INTO SUNDAY. ALTHOUGH
AGAIN WOULD GENERALLY THINK CENTROID OF MCS ACTIVITY ON SYNOPTIC
SCALE COULD SHIFT SOUTH EACH DAY THUS HIGHER CHCS WOULD APPEAR TO
SHIFT INTO SRN ZONES BY SUNDAY/SUNDAY NIGHT. WITH ERLY FLOW
SETTING UP SATURDAY BEHIND EXPECTED MCS TOMORROW NIGHT...LEANED
TOWARD COOLER NAM FOR MAX TEMPS. NO CHANGES TO SUNDAY MAX TEMPS AT
THIS TIME.
DRIER WEATHER STILL ON TAP MONDAY AND PROBABLY TUESDAY AS WELL AS
NWRLY FLOW SENDS HIGH PRESSURE THROUGH ERN PLAINS AND FORECAST WAS
MOSTLY DRY. AFTER THAT...RETURNING MOISTURE WILL BRING INCREASING
TSTM RISK THRU END OF WEEK ALTHOUGH FOR THE TIME BEING KEPT MOST
POPS IN LOWER CHC RANGE.
CHERMOK
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BISMARCK ND
257 PM CDT FRI JUN 14 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 257 PM CDT FRI JUN 14 2013
MAIN CONCERN FOR THE SHORT TERM WILL BE THUNDERSTORMS ACROSS THE
NORTHWEST THIS EVENING. SATELLITE AND THE RAP MODEL SHOW A MID
LEVEL IMPULSE THAT WILL TRACK THROUGH NORTHEAST MONTANA INTO
NORTHWEST NORTH DAKOTA THIS EVENING. WILL ADD A CHANCE FOR
THUNDERSTORMS FOR THE EVENING HOURS. TO THE EAST...A COLD FRONT
WAS MAKING ITS WAY ACROSS CENTRAL NORTH DAKOTA. STILL BELIEVE
THERE WILL BE A CHANCE FOR CONVECTIVE INITIATION ACROSS THE EAST
CENTRAL TONIGHT. AFTER SUNRISE SATURDAY...BELIEVE ITS REASONABLE
FOR ALL THE PRECIPITATION TO BE NORTH AND EAST OF THE REGION .
WILL GO DRY FOR SATURDAY IN GENERAL SUBSIDENCE ON THE SOUTH AND
WEST SIDE OF THE UPPER LOW WHICH WILL BE IN CANADA.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 257 PM CDT FRI JUN 14 2013
NO SIGNIFICANT WEATHER TO HIGHLIGHT THE EXTENDED FORECAST WITH
BELOW NORMAL TEMPERATURES SUNDAY AND MONDAY TRANSITIONING TO NEAR
NORMAL VALUES THROUGH THE REMAINDER OF NEXT WEEK.
THE 12 UTC GUIDANCE SUITE IS IN GOOD AGREEMENT THROUGH WEDNESDAY
WITH A DIVERGENCE IN SOLUTIONS THURSDAY INTO FRIDAY. FOR
SUNDAY...A FILLING UPPER LEVEL LOW PROPAGATES SOUTHEAST OUT OF
CANADA WHICH SUPPORTS DIURNALLY DRIVEN ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS UNDER THE COLD CORE ALOFT. COOL HIGH
PRESSURE IN THE WAKE OF THIS SYSTEM FOR MONDAY SUGGESTS WIDESPREAD
HIGHS IN THE UPPER 60S AND LOWER 70S...ABOUT 7 TO 10 DEGREES BELOW
NORMAL. THEREAFTER...UPPER LEVEL RIDGING BUILDS ACROSS THE
NORTHERN PLAINS WITH A RETURN TO NORMAL HIGHS NEAR 80. UNCERTAINTY
INCREASES FOR CONVECTIVE CHANCES THURSDAY THROUGH FRIDAY IN REGARDS
TO THE PROPAGATION AND EVOLUTION OF THE UPPER LEVEL LOW COMING ON
SHORE TO THE PACIFIC NORTHWEST ON WEDNESDAY...AND HOW FAR EAST THE
LOW CAN PROPAGATE TO TURN TO THE UPPER LEVEL FLOW TO THE SOUTHWEST
ACROSS THE NORTHERN PLAINS. OVERALL...A BLEND OF THE 12 UTC
GUIDANCE SUITE WAS USED FOR MOST FIELDS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 257 PM CDT FRI JUN 14 2013
AT 2 PM CDT...SURFACE LOW PRESSURE ACROSS CENTRAL ALBERTA AND
SASKATCHEWAN HAD AN ASSOCIATED COLD FRONT PROGRESSING EAST
THROUGH CENTRAL NORTH DAKOTA. THE FRONT WILL BE THE FOCUS FOR
WIDELY SCATTERED THUNDERSTORMS IN THE JAMES RIVER VALLEY LATE THIS
AFTERNOON AND TONIGHT. AN UPPER LEVEL IMPULSE WILL BRING A CHANCE
OF THUNDERSTORMS NORTHWEST THIS EVENING. TIMING STILL UNCERTAIN
FOR THUNDERSTORMS SO AT THIS TIME WILL ONLY MENTION VCTS AT
KJMS/KISN. OTHERWISE VFR THROUGH TAF PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...WAA
LONG TERM...AYD
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
954 AM CDT FRI JUN 14 2013
.UPDATE...
ISSUED AT 950 AM CDT FRI JUN 14 2013
MAIN CLUSTER OF CONVECTION VCNTY MOT LIFTING NNE AS SHORTWAVE
LIFTS INTO S CENTRAL CANADA AND AT MOST MAY CLIP FAR NE FA.
ELSEWHERE IN OUR FA CONVECTION OVERALL WEAKENING WITH LTG STRIKES NO
LONGER NOTED. BASED ON CURRENT RADAR TRENDS...CLOUDS MOVING INTO
FA AND BOUNDARY WELL TO OUR WEST BACKED OFF ON POPS REMAINDER OF
AM INTO MID AFTERNOON. CLOUDS MOVING IN AND MAY RESTRICT
TEMPERATURE RECOVERY SOME BUT ANY BREAKS WILL LIFT TEMPERATURES SO
WILL LEAVE TEMPS AS IS FOR NOW.
UPDATE ISSUED AT 702 AM CDT FRI JUN 14 2013
MORE SHOWERS AND A FEW STORMS HAVE GONE UP ACROSS THE NORTHWESTERN
AND NORTH CENTRAL CWA ALONG AN AREA OF WARM AIR ADVECTION. RAP HAS
SEEMED TO HAVE A GOOD HANDLE ON THIS ACTIVITY OVERNIGHT AND HAS
SOME PRECIP CONTINUING OVER THE CENTRAL CWA FOR THE NEXT FEW
HOURS. THE NEXT ROUND IS SEEN ACROSS CENTRAL ND ON RADAR AND
SHOULD START ENTERING THE WESTERN CWA BY LATE MORNING. ADJUSTED
POPS ACCORDINGLY FOR TODAYS ACTIVITY.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 347 AM CDT FRI JUN 14 2013
MAIN CONCERN FOR THE SHORT TERM IS HOW MUCH CONVECTION WE GET
TODAY AND IF ANY WILL BE SEVERE.
THE MAIN UPPER TROUGH IS STILL OUT OVER WA/OR/ID BUT WV LOOP SHOWS
SOME LEAD SHORTWAVES SETTING OFF ACTIVITY OVER THE NORTHERN
ROCKIES. THE UPPER RIDGE AXIS CURRENTLY OVER THE RED RIVER VALLEY
WILL MOVE EAST INTO MN TODAY. THERE HAS BEEN SHOWERS AND STORMS
DEVELOPING OVER THE SOUTHEASTERN COUNTIES AS WELL AS JUST OUTSIDE
OUR NORTHWEST ALONG THE FRONT EDGE OF THE 850MB WARM AIR ADVECTION
AND RIGHT EXIT REGION OF THE LOW LEVEL JET. NONE OF THE MODELS
EXCEPT FOR THE RAP HAS HAD A GOOD HANDLE ON THE ACTIVITY. THINK
THAT THIS BAND OF LIGHT CONVECTION WILL SLOWLY SPREAD EASTWARD
DURING THE MORNING HOURS. WILL MAKE LAST MINUTE ADJUSTMENTS TO
POPS/WX BASED ON RADAR TRENDS.
BY LATE THIS AFTERNOON AND EVENING...THE MAIN SHORTWAVE WILL
APPROACH AND WILL HELP PUSH THE SFC TROUGH AXIS INTO THE RED RIVER
VALLEY. THINK THAT THERE WILL BE PLENTY OF LIFT TO WORK WITH...THE
QUESTION IS HOW MUCH INSTABILITY WILL BE AVAILABLE FOR CONVECTION.
THE MODELS HAVE DECENT 1000-2000 J/KG ALONG THE SFC TROUGH AXIS
THIS AFTERNOON...BUT THERE IS ALSO QUITE A BIT OF A CAP WITH 700MB
TEMPS IN THE LOW TEENS C. THERE IS ALSO THE QUESTION OF HOW MUCH
CLOUD COVER WILL BE HANGING AROUND FROM THIS MORNINGS ACTIVITY.
THERE CONTINUES TO BE QUITE A BIT OF PRECIP BREAKING OUT ALONG THE
SFC TROUGH ACCORDING TO THE MODELS. WILL CONTINUE TO KEEP FAIRLY
HIGH POPS AND WILL MENTION THE POSSIBILITY OF SOME HAIL AND WINDS
IN THE HWO...BUT WILL KEEP A MENTION OUT OF THE GRIDS FOR NOW.
THE UPPER TROUGH WILL MOVE INTO CENTRAL CANADA AND THE NORTHERN
PLAINS TONIGHT...WITH THE SFC TROUGH AXIS/WEAK FRONTAL BOUNDARY
PUSHING THE REST OF THE WAY THROUGH THE CWA. DECENT WINDS WILL
HELP KEEP LOWS IN THE 50S. NEAR ZONAL FLOW SETS UP OVER ND FOR
SATURDAY WITH THE MAIN SFC LOW WELL TO OUR NORTH OVER MANT/SASK.
WEST WINDS WILL REMAIN OVER THE PLAINS...AND WITH THE BEST COLD
AIR ADVECTION HOLDING OFF FOR NOW...HIGHS ON SATURDAY SHOULD AGAIN
CLIMB INTO THE MID TO UPPER 70S.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 347 AM CDT FRI JUN 14 2013
FOR THE REST OF THE WEEKEND...ANOTHER UPPER TROUGH WILL BEGIN TO
DIG DOWN OUT OF CANADA BY SUNDAY...PUSHING A MUCH MORE SIGNIFICANT
COLD FRONT DOWN INTO THE CWA. THERE COULD BE SOME SHOWERS AND
THUNDERSTORMS ALONG AND BEHIND THE FRONT...SO CONTINUED WITH
CHANCE POPS MAINLY ALONG THE INTERNATIONAL BORDER SUNDAY. PRECIP
WILL MOVE OFF TO THE SOUTH AND EAST SUNDAY NIGHT AS THE COLD FRONT
PUSHES THE REST OF THE WAY THROUGH THE CWA. HIGHS ON SUNDAY WILL
DEPEND ON EXACT TIMING OF THE FRONT...BUT FOR NOW HAVE HIGHS
AROUND 70 IN THE NORTHWEST AND NEAR 80 IN THE SOUTHEAST.
MODELS IN FAIR AGREEMENT WITH THE BEGINNING OF THE NEXT WORK WEEK. A
COOL MONDAY WILL SEE A CHC FOR SOME SHOWER ACTIVITY WITH COLD CORE
ALOFT ALLOWING LOW CONVECTIVE TEMPS TO BE REACHED IF ANY SFC SOLAR
OCCURS. SFC HIGH WITH 500MB RIDGING WILL GIVE OVERALL DRY AND WARM
WEATHER TUESDAY AND WEDNESDAY BEFORE THE NEXT SYSTEM MOVES INTO THE
REGION THURSDAY BRINGING THE NEXT CHC OF RAIN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 702 AM CDT FRI JUN 14 2013
VFR CONDITIONS WILL CONTINUE THROUGH MOST OF THE PERIOD ALTHOUGH
THERE COULD BE SOME DROPS TO MVFR UNDER SHOWERS AND THUNDERSTORMS
FOR A BRIEF PERIOD. FOR NOW IT SEEMS THAT THIS MORNINGS ACTIVITY
WILL BE NORTH OF THE TAF SITES...BUT LATER ON THIS AFTERNOON
SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS THE AREA. SOUTHEASTERLY
WINDS WILL PICK UP INTO THE 15 TO 20 KT RANGE WITH SOME HIGHER
GUSTS. AFTER A TROUGH AXIS/WEAK COLD FRONT MOVES THROUGH DURING
THE AFTERNOON TO EVENING...WINDS WILL SHIFT TO THE WEST AND
DECREASE. SKIES SHOULD BEGIN TO CLEAR TOWARDS THE END OF THE PERIOD.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...VOELKER
SHORT TERM...JR
LONG TERM...JR/JK
AVIATION...JR
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
702 AM CDT FRI JUN 14 2013
.UPDATE...
ISSUED AT 702 AM CDT FRI JUN 14 2013
MORE SHOWERS AND A FEW STORMS HAVE GONE UP ACROSS THE NORTHWESTERN
AND NORTH CENTRAL CWA ALONG AN AREA OF WARM AIR ADVECTION. RAP HAS
SEEMED TO HAVE A GOOD HANDLE ON THIS ACTIVITY OVERNIGHT AND HAS
SOME PRECIP CONTINUING OVER THE CENTRAL CWA FOR THE NEXT FEW
HOURS. THE NEXT ROUND IS SEEN ACROSS CENTRAL ND ON RADAR AND
SHOULD START ENTERING THE WESTERN CWA BY LATE MORNING. ADJUSTED
POPS ACCORDINGLY FOR TODAYS ACTIVITY.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 347 AM CDT FRI JUN 14 2013
MAIN CONCERN FOR THE SHORT TERM IS HOW MUCH CONVECTION WE GET
TODAY AND IF ANY WILL BE SEVERE.
THE MAIN UPPER TROUGH IS STILL OUT OVER WA/OR/ID BUT WV LOOP SHOWS
SOME LEAD SHORTWAVES SETTING OFF ACTIVITY OVER THE NORTHERN
ROCKIES. THE UPPER RIDGE AXIS CURRENTLY OVER THE RED RIVER VALLEY
WILL MOVE EAST INTO MN TODAY. THERE HAS BEEN SHOWERS AND STORMS
DEVELOPING OVER THE SOUTHEASTERN COUNTIES AS WELL AS JUST OUTSIDE
OUR NORTHWEST ALONG THE FRONT EDGE OF THE 850MB WARM AIR ADVECTION
AND RIGHT EXIT REGION OF THE LOW LEVEL JET. NONE OF THE MODELS
EXCEPT FOR THE RAP HAS HAD A GOOD HANDLE ON THE ACTIVITY. THINK
THAT THIS BAND OF LIGHT CONVECTION WILL SLOWLY SPREAD EASTWARD
DURING THE MORNING HOURS. WILL MAKE LAST MINUTE ADJUSTMENTS TO
POPS/WX BASED ON RADAR TRENDS.
BY LATE THIS AFTERNOON AND EVENING...THE MAIN SHORTWAVE WILL
APPROACH AND WILL HELP PUSH THE SFC TROUGH AXIS INTO THE RED RIVER
VALLEY. THINK THAT THERE WILL BE PLENTY OF LIFT TO WORK WITH...THE
QUESTION IS HOW MUCH INSTABILITY WILL BE AVAILABLE FOR CONVECTION.
THE MODELS HAVE DECENT 1000-2000 J/KG ALONG THE SFC TROUGH AXIS
THIS AFTERNOON...BUT THERE IS ALSO QUITE A BIT OF A CAP WITH 700MB
TEMPS IN THE LOW TEENS C. THERE IS ALSO THE QUESTION OF HOW MUCH
CLOUD COVER WILL BE HANGING AROUND FROM THIS MORNINGS ACTIVITY.
THERE CONTINUES TO BE QUITE A BIT OF PRECIP BREAKING OUT ALONG THE
SFC TROUGH ACCORDING TO THE MODELS. WILL CONTINUE TO KEEP FAIRLY
HIGH POPS AND WILL MENTION THE POSSIBILITY OF SOME HAIL AND WINDS
IN THE HWO...BUT WILL KEEP A MENTION OUT OF THE GRIDS FOR NOW.
THE UPPER TROUGH WILL MOVE INTO CENTRAL CANADA AND THE NORTHERN
PLAINS TONIGHT...WITH THE SFC TROUGH AXIS/WEAK FRONTAL BOUNDARY
PUSHING THE REST OF THE WAY THROUGH THE CWA. DECENT WINDS WILL
HELP KEEP LOWS IN THE 50S. NEAR ZONAL FLOW SETS UP OVER ND FOR
SATURDAY WITH THE MAIN SFC LOW WELL TO OUR NORTH OVER MANT/SASK.
WEST WINDS WILL REMAIN OVER THE PLAINS...AND WITH THE BEST COLD
AIR ADVECTION HOLDING OFF FOR NOW...HIGHS ON SATURDAY SHOULD AGAIN
CLIMB INTO THE MID TO UPPER 70S.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 347 AM CDT FRI JUN 14 2013
FOR THE REST OF THE WEEKEND...ANOTHER UPPER TROUGH WILL BEGIN TO
DIG DOWN OUT OF CANADA BY SUNDAY...PUSHING A MUCH MORE SIGNIFICANT
COLD FRONT DOWN INTO THE CWA. THERE COULD BE SOME SHOWERS AND
THUNDERSTORMS ALONG AND BEHIND THE FRONT...SO CONTINUED WITH
CHANCE POPS MAINLY ALONG THE INTERNATIONAL BORDER SUNDAY. PRECIP
WILL MOVE OFF TO THE SOUTH AND EAST SUNDAY NIGHT AS THE COLD FRONT
PUSHES THE REST OF THE WAY THROUGH THE CWA. HIGHS ON SUNDAY WILL
DEPEND ON EXACT TIMING OF THE FRONT...BUT FOR NOW HAVE HIGHS
AROUND 70 IN THE NORTHWEST AND NEAR 80 IN THE SOUTHEAST.
MODELS IN FAIR AGREEMENT WITH THE BEGINNING OF THE NEXT WORK WEEK. A
COOL MONDAY WILL SEE A CHC FOR SOME SHOWER ACTIVITY WITH COLD CORE
ALOFT ALLOWING LOW CONVECTIVE TEMPS TO BE REACHED IF ANY SFC SOLAR
OCCURS. SFC HIGH WITH 500MB RIDGING WILL GIVE OVERALL DRY AND WARM
WEATHER TUESDAY AND WEDNESDAY BEFORE THE NEXT SYSTEM MOVES INTO THE
REGION THURSDAY BRINGING THE NEXT CHC OF RAIN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 702 AM CDT FRI JUN 14 2013
VFR CONDITIONS WILL CONTINUE THROUGH MOST OF THE PERIOD ALTHOUGH
THERE COULD BE SOME DROPS TO MVFR UNDER SHOWERS AND THUNDERSTORMS
FOR A BRIEF PERIOD. FOR NOW IT SEEMS THAT THIS MORNINGS ACTIVITY
WILL BE NORTH OF THE TAF SITES...BUT LATER ON THIS AFTERNOON
SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS THE AREA. SOUTHEASTERLY
WINDS WILL PICK UP INTO THE 15 TO 20 KT RANGE WITH SOME HIGHER
GUSTS. AFTER A TROUGH AXIS/WEAK COLD FRONT MOVES THROUGH DURING
THE AFTERNOON TO EVENING...WINDS WILL SHIFT TO THE WEST AND
DECREASE. SKIES SHOULD BEGIN TO CLEAR TOWARDS THE END OF THE PERIOD.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...JR
LONG TERM...JR/JK
AVIATION...JR
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
348 AM CDT FRI JUN 14 2013
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 347 AM CDT FRI JUN 14 2013
MAIN CONCERN FOR THE SHORT TERM IS HOW MUCH CONVECTION WE GET
TODAY AND IF ANY WILL BE SEVERE.
THE MAIN UPPER TROUGH IS STILL OUT OVER WA/OR/ID BUT WV LOOP SHOWS
SOME LEAD SHORTWAVES SETTING OFF ACTIVITY OVER THE NORTHERN
ROCKIES. THE UPPER RIDGE AXIS CURRENTLY OVER THE RED RIVER VALLEY
WILL MOVE EAST INTO MN TODAY. THERE HAS BEEN SHOWERS AND STORMS
DEVELOPING OVER THE SOUTHEASTERN COUNTIES AS WELL AS JUST OUTSIDE
OUR NORTHWEST ALONG THE FRONT EDGE OF THE 850MB WARM AIR ADVECTION
AND RIGHT EXIT REGION OF THE LOW LEVEL JET. NONE OF THE MODELS
EXCEPT FOR THE RAP HAS HAD A GOOD HANDLE ON THE ACTIVITY. THINK
THAT THIS BAND OF LIGHT CONVECTION WILL SLOWLY SPREAD EASTWARD
DURING THE MORNING HOURS. WILL MAKE LAST MINUTE ADJUSTMENTS TO
POPS/WX BASED ON RADAR TRENDS.
BY LATE THIS AFTERNOON AND EVENING...THE MAIN SHORTWAVE WILL
APPROACH AND WILL HELP PUSH THE SFC TROUGH AXIS INTO THE RED RIVER
VALLEY. THINK THAT THERE WILL BE PLENTY OF LIFT TO WORK WITH...THE
QUESTION IS HOW MUCH INSTABILITY WILL BE AVAILABLE FOR CONVECTION.
THE MODELS HAVE DECENT 1000-2000 J/KG ALONG THE SFC TROUGH AXIS
THIS AFTERNOON...BUT THERE IS ALSO QUITE A BIT OF A CAP WITH 700MB
TEMPS IN THE LOW TEENS C. THERE IS ALSO THE QUESTION OF HOW MUCH
CLOUD COVER WILL BE HANGING AROUND FROM THIS MORNINGS ACTIVITY.
THERE CONTINUES TO BE QUITE A BIT OF PRECIP BREAKING OUT ALONG THE
SFC TROUGH ACCORDING TO THE MODELS. WILL CONTINUE TO KEEP FAIRLY
HIGH POPS AND WILL MENTION THE POSSIBILITY OF SOME HAIL AND WINDS
IN THE HWO...BUT WILL KEEP A MENTION OUT OF THE GRIDS FOR NOW.
THE UPPER TROUGH WILL MOVE INTO CENTRAL CANADA AND THE NORTHERN
PLAINS TONIGHT...WITH THE SFC TROUGH AXIS/WEAK FRONTAL BOUNDARY
PUSHING THE REST OF THE WAY THROUGH THE CWA. DECENT WINDS WILL
HELP KEEP LOWS IN THE 50S. NEAR ZONAL FLOW SETS UP OVER ND FOR
SATURDAY WITH THE MAIN SFC LOW WELL TO OUR NORTH OVER MANT/SASK.
WEST WINDS WILL REMAIN OVER THE PLAINS...AND WITH THE BEST COLD
AIR ADVECTION HOLDING OFF FOR NOW...HIGHS ON SATURDAY SHOULD AGAIN
CLIMB INTO THE MID TO UPPER 70S.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 347 AM CDT FRI JUN 14 2013
FOR THE REST OF THE WEEKEND...ANOTHER UPPER TROUGH WILL BEGIN TO
DIG DOWN OUT OF CANADA BY SUNDAY...PUSHING A MUCH MORE SIGNIFICANT
COLD FRONT DOWN INTO THE CWA. THERE COULD BE SOME SHOWERS AND
THUNDERSTORMS ALONG AND BEHIND THE FRONT...SO CONTINUED WITH
CHANCE POPS MAINLY ALONG THE INTERNATIONAL BORDER SUNDAY. PRECIP
WILL MOVE OFF TO THE SOUTH AND EAST SUNDAY NIGHT AS THE COLD FRONT
PUSHES THE REST OF THE WAY THROUGH THE CWA. HIGHS ON SUNDAY WILL
DEPEND ON EXACT TIMING OF THE FRONT...BUT FOR NOW HAVE HIGHS
AROUND 70 IN THE NORTHWEST AND NEAR 80 IN THE SOUTHEAST.
MODELS IN FAIR AGREEMENT WITH THE BEGINNING OF THE NEXT WORK WEEK. A
COOL MONDAY WILL SEE A CHC FOR SOME SHOWER ACTIVITY WITH COLD CORE
ALOFT ALLOWING LOW CONVECTIVE TEMPS TO BE REACHED IF ANY SFC SOLAR
OCCURS. SFC HIGH WITH 500MB RIDGING WILL GIVE OVERALL DRY AND WARM
WEATHER TUESDAY AND WEDNESDAY BEFORE THE NEXT SYSTEM MOVES INTO THE
REGION THURSDAY BRINGING THE NEXT CHC OF RAIN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY EVENING)
ISSUED AT 1159 PM CDT THU JUN 13 2013
EXPECT GENLY FAIR SKIES AND LIGHT EAST TO SOUTHEAST BLAYER FLOW
THROUGH THE LATE EVENING AND OVERNIGHT PERIODS. INCREASING MID TO
UPPER LEVEL CLOUDS EARLY ON FRIDAY. ISOLD TSMS IN FAR SERN ND
DURING THE OVERNIGHT. AREAS OF MVFR CIGS AND VSBYS IN TSTMS
EXPECTED ACROSS ERN ND FROM LATE FORENOON INTO FRIDAY AFTERNOON...
SPREADING INTO WRN MN THROUGH MID AND LATE AFTERNOON.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...JR
LONG TERM...JR/JK
AVIATION...GUST
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1217 AM CDT FRI JUN 14 2013
.UPDATE...
ISSUED AT 919 PM CDT THU JUN 13 2013
MAIN CHANGE TO FORECAST INVOLVES PRECIPITATION CHANCES. FOR THIS
EVENING...DO EXPECT LIGHT SHOWERS/THUNDERSTORMS TO PERSIST IN NW
IA UNTIL ABOUT MID NIGHT. THIS IS ASSOCIATED WITH A WEAK 700 MB
FRONT.
FARTHER WEST...AM GOING TO DELAY CONVECTIVE CHANCES WEST OF I29
UNTIL AFTER 06Z AND REALLY NOT GO ABOVE A 20 PERCENT UNTIL AFTER
09Z. THE UPPER LEVEL WAVE IS WELL TO THE WEST YET AND AS A RESULT
THE STEEPER LAPSE RATES DO NOT ARRIVE INTO THE JAMES VALLEY UNTIL
06Z. OF EVEN GREATER CONCERN THE LOW LEVEL JET DOES NOT REALLY
INCREASE UNTIL AFTER 06Z. AS A RESULTS THE BEST THETA-E ADVECTION
IS NOT UNTIL ALMOST 12Z. BOTH RAP AND HRRR ARE MUCH SLOWER IN
DEVELOPING CONVECTION. IN FACT THE RAP HAS ALMOST NO CONVECTION
UNTIL AFTER 12Z. THAT MAY BE A LITTLE TOO SLOW GIVEN MUCAPES OF
1000 TO 1500 J/KG AND CIN NEAR ZERO AT KFSD BY 12Z AND APPROACHING
WEAK WAVE. CURRENT MENTION OF NICKEL TO HALF-DOLLAR SIZE HAIL IN
HWO FOR LATE TONIGHT AND TOMORROW SEEMS REASONABLE GIVEN AMOUNT OF
CAPE AVAILABLE TO STORMS...EVEN WITH EFFECTIVE SHEAR AROUND 20 KTS
FOR MORNING CONVECTION. TEMPERATURES LOOK ON TRACK FOR TONIGHT.
GRIDS UPDATED AND WILL UPDATE HWO SHORTLY TO SLOW DOWN TIMING OF
CONVECTION.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 405 PM CDT THU JUN 13 2013
ISOLATED SHOWERS AND THUNDERSTORMS THIS AFTERNOON WILL PASS OVER THE
AREA FROM SIOUX CITY TO STORM LAKE AND SOUTH WITH LITTLE FANFARE.
LATER TONIGHT IN AXIS OF INCREASING MOISTURE AND
INSTABILITY...ISOLATED STORMS ARE EXPECTED TO DEVELOP OVER MORE OF
THE AREA AND MOVE FROM WEST TO EAST...PROBABLY BECOMING SCATTERED BY
DAYBREAK IN THE EAST. AIR STILL DOES NOT LOOK UNSTABLE ENOUGH GIVEN
AVAILABLE MOISTURE AND MEAGER LIFT TO PRODUCE SEVERE WEATHER...BUT
SOME LATE COULD PUT DOWN SOME SMALL HAIL. THIS ACTIVITY WILL BE ONLY
SLOWLY INCREASING AS IT MOVES EAST INTO BETTER AREA OF THERMAL LIFT.
HOWEVER...INSTEAD OF DECREASING FRIDAY MORNING AS NOCTURNAL ACTIVITY
OFTEN DOES...EXPECT A CONTINUED SLOW INCREASE IN COVERAGE BECAUSE OF
INCREASING DYNAMIC SUPPORT AS WAVE AND SURFACE BOUNDARY APPROACH.
NIGHTTIME ACTIVITY HAS LITTLE SUPPORT FROM LOW LEVEL JET WHICH
DEVELOPS STRONGLY TO THE WEST OF OUR AREA...BUT EVEN THOUGH EXPECTED
TO DECREASE FRIDAY...IT WILL THEN BE MOVING INTO OUR AREA...SO
EXPECT SCATTERED ELEVATED STORMS TO CONTINUE DEVELOPING AT A TIME
WHEN THEY WOULD NORMALLY BE DECREASING. THE QUESTION REMAINS AT WHAT
TIME LATE IN THE DAY THE STORMS COULD BECOME MORE SURFACE BASED OR
WHETHER THEY EVEN WILL. HOWEVER...INSTABILITY SEEMS ENOUGH BY MIDDAY
FRIDAY FOR EVEN THESE ELEVATED STORMS TO PRODUCE ISOLATED SEVERE
HAIL REPORTS. TEMPERATURES TONIGHT AND FRIDAY WILL BE KEPT CLOSE TO
WHAT WE HAVE BEEN GOING FOR...A LITTLE COOLER THAN GUIDANCE IN THE
EAST DUE TO THE EXPECTED CLOUD COVER AND SCATTERED CONVECTION. WINDS
WILL INCREASE TO BREEZY LEVELS IN THE EAST FOR A WHILE FRIDAY AHEAD
OF SURFACE TROUGH/OCCLUDED FRONT.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 405 PM CDT THU JUN 13 2013
QUESTION FOR FRIDAY EVENING INTO THE OVERNIGHT IS WHETHER SURFACE
BASED CONVECTION FIRES ALONG THE APPROACHING FRONT...AND IF IT
DOES...WHEN AND WHERE. ELEVATED ACTIVITY ONGOING ACROSS OUR EAST
DURING THE AFTERNOON WILL LIKELY HINDER SURFACE HEATING SOMEWHAT.
ALSO A STRONG CAP IS FORECAST TO BE IN PLACE...ALTHOUGH THIS SHOULD
GRADUALLY BE ERODED AS COOLER MID LEVEL TEMPERATURES MOVE INTO THE
AREA. BEST UPPER FORCING WITH THE MAIN WAVE WILL STAY WELL TO OUR
NORTH. MEANWHILE BEST FRONTOGENETICAL FORCING LOOKS TO BE FOCUSED
ACROSS CENTRAL NEBRASKA. GIVEN THIS...COMBINED WITH UNCERTAINTY ON
HOW MUCH HEATING WE GET DURING THE DAY...SEEMS LIKE MOST LIKELY
SOLUTION HAS ONE AREA OF SHOWERS AND STORMS FORM NORTH OF OUR CWA
WITH THE BETTER UPPER LEVEL FORCING. AND ANOTHER AREA FORM IN SOUTH
CENTRAL NEBRASKA ALONG THE STRONGER PORTION OF THE
BOUNDARY...LEAVING OUR CWA IN THE MIDDLE. SUBTLE SIGNS THAT A
SECONDARY WAVE MAY EJECT OUT OF THE COLORADO ROCKIES DURING THE
AFTERNOON...WHICH MAY AID IN THE NEBRASKA DEVELOPMENT. EXPECT THIS
ACTIVITY TO THEN POTENTIALLY INCREASE NORTHEAST ALONG THE FRONT...AS
THE SECONDARY WAVE EJECTS EAST AND CAPPING WEAKENS DUE TO HEATING
AND COOLING ALOFT. QUESTION IS HOW FAR NORTH THIS CONVECTION GETS.
INDIVIDUAL STORM MOTION WILL TEND TO BE ALMOST DUE EASTERLY...THUS
THE BEST CHANCE WILL PROBABLY END UP ACROSS NORTHWEST IOWA AND
EXTREME SOUTHEAST SOUTH DAKOTA IN THE EVENING INTO THE OVERNIGHT.
STORMS WOULD INITIALLY BE SUPERCELLS BEFORE PROBABLY BECOMING MORE OF
A CLUSTER...WITH LARGE HAIL AND STRONG WINDS THE MAIN THREAT...BUT
GIVEN LOW LEVEL WIND FIELDS AN ISOLATED TORNADO WOULD ALSO BE
POSSIBLE IF STORMS GET INTO OUR AREA EARLY ENOUGH. FURTHER NORTH THE
THREAT SEEMS LOWER. HOWEVER WILL HAVE TO KEEP AN EYE ON THINGS...AS
IF AN ISOLATED STORM IS ABLE TO FORM ALONG THE FRONT NEAR THE JAMES
RIVER...IT WOULD LIKELY BECOME SUPERCELLUAR WITH CAPE AROUND 2000
J/KG AND DEEP LAYER SHEAR OF 40 OR MORE KTS.
SATURDAY SEES THE FRONT LIKELY TO OUR SOUTH. BUT DECENT UPPER
SUPPORT IN THE RIGHT ENTRANCE OF A STRONG UPPER JET IS EXPECTED.
MODELS ALSO SUGGEST THAT LOW TO MODERATE INSTABILITY MAY LINGER
ALONG AND SOUTH OF INTERSTATE 90. THUS WHILE IT WOULD SEEM LIKELY
THAT THE GREATEST THUNDERSTORM COVERAGE WILL REMAIN SOUTH IN THE
VICINITY OF THE FRONT...CAN NOT RULE OT ISOLATED TO SCATTERED
ACTIVITY SOUTH OF INTERSTATE 90. AGAIN SHEAR PROFILES WOULD SUPPORT A
LARGE HAIL AND WIND THREAT WITH ANY STORM THAT DOES FORM. HIGHS
DEPENDENT ON CLOUD COVER AND COVERAGE OF SHOWERS AND STORMS...BUT
NEAR SEASONABLE READINGS IN THE UPPER 70S TO LOW 80S SEEM PROBABLE.
ON SUNDAY A STRONGER WAVE WILL EJECT SOUTHEAST OUT OF CANADA AND
INTO THE FAR NORTHERN PLAINS. STILL UNCERTAINTY ON AVAILABLE
MOISTURE AND WHERE THE BEST FORCING ENDS UP. WIND FIELDS WOULD
SUGGEST A SEVERE THREAT WITH ANY STORMS THAT COULD FORM...BUT AGAIN
LATEST INDICATIONS ARE THAT THE BEST THREAT MAY END UP SOUTH OF US.
BUT SOMETHING TO KEEP AN EYE ON. HIGHS PROBABLY A COUPLE DEGREES
WARMER ON SUNDAY...BUT STILL AROUND OR JUST SLIGHTLY ABOVE AVERAGE.
DRIER AND COOLER AIR MOVES IN ON MONDAY BEHIND THE WAVE. MODELS
COMING IN A BIT COOLER ALOFT...AND THUS HIGHS LOOK LIKE THEY WILL
END UP AT LEAST A FEW DEGREES BELOW SEASONABLE NORMALS...WITH MID TO
UPPER 70S EXPECTED. RIDGING THEN BEGINS TO BUILD IN TUESDAY INTO
THURSDAY. ALTHOUGH LATEST RUNS SLOW THIS DOWN A BIT...SUGGESTING
SLIGHTLY COOLER HIGHS POSSIBLE. EITHER WAY EXPECTING READINGS
AROUND AVERAGE THROUGH THURSDAY...WITH A SLOW WARMING TREND EACH
DAY. RIDGE AXIS SHOULD MOVE OVERHEAD AROUND WEDNESDAY. UNCERTAINTY
ON TIMING AND PLACEMENT OF SUBTLE WAVES RIDING OVER THE RIDGE...BUT
THE SETUP WOULD SUGGEST AT LEAST THE MENTION OF A RETURN OF ISOLATED
SHOWERS AND THUNDERSTORMS ANYTIME LATER WEDNESDAY INTO THURSDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1210 AM CDT FRI JUN 14 2013
GENERAL VFR CONDITIONS THROUGH THE TAF PERIOD. EXCEPTIONS WILL BE
IN BRIEF REDUCED VISIBILITIES IN CONVECTION WHICH MAY DEVELOP
ACROSS PORTIONS OF THE AREA IN THE MORNING HOURS OF FRIDAY...THEN
AGAIN IN THE AFTERNOON. SOUTHERLY WINDS WILL PICK UP BY LATE
MORNING AND CONTINUE INTO THE AFTERNOON.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
UPDATE...SCHUMACHER
SHORT TERM...
LONG TERM...CHENARD
AVIATION...JM
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
656 PM CDT SAT JUN 15 2013
.UPDATE...
LATEST SATELLITE AND WSR-88D DATA INDICATE SHOWERS AND
THUNDERSTORMS HAVE DISSIPATED ACROSS WEST CENTRAL TEXAS. VISIBLE
SATELLITE LOOP SHOWS CLOUD MOVEMENT AT A COUPLE DIFFERENT LEVELS.
ONE...AT THE LOWEST LEVEL...INDICATES OPEN CELL CUMULUS MOVING
MAINLY TOWARD THE NORTHWEST ACROSS WEST CENTRAL TEXAS.
ALOFT...OTHER CLOUDS ARE MOVING TOWARD THE EAST OR SOUTHEAST. OVER
THE CONCHO VALLEY...DISSIPATING CUMULUS IMPLIES SUBSIDENCE. THE
MESOSCALE CONVECTIVE VORTEX SIGNATURES WE WERE OBSERVING EARLIER
TODAY IN THE VISIBLE IMAGERY APPEAR TO HAVE DISSIPATED. THE LATEST
RUC DATA INDICATES CONVECTION WILL BE LIMITED TO MAINLY OUR
NORTHWEST HILL COUNTRY AND HEARTLAND COUNTIES. HOWEVER...DYNAMICS
ALOFT LOOKS WEAK. THUS...I HAVE REDUCED POPS ACROSS THE SAME AREA
WE HAD IN OUR PREVIOUS FORECAST PACKAGE TO SLIGHT CHANCE FOR THE
REMAINDER OF TONIGHT. AGAIN...THE RUC INDICATES OUR SOUTHEASTERN
COUNTIES APPEAR TO BE THE BEST PLACE FOR RAIN FOR THE REMAINDER OF
TONIGHT. BUT...THE LATEST HPC QPF GUIDANCE GRIDS FOR TONIGHT HAVE
ZERO QPF FOR ALL OF WEST CENTRAL TEXAS.
I RECENTLY SENT A NEW SUITE OF PUBLIC AND FIRE ALPHANUMERIC
PRODUCTS TO REFLECT THESE CHANGES.
HUBER
&&
.PREV DISCUSSION... /ISSUED 622 PM CDT SAT JUN 15 2013/
DISCUSSION...
/SEE BELOW FOR AVIATION DISCUSSION/
AVIATION...
WITH A MOIST BOUNDARY LAYER IN PLACE AND PARTIALLY CLEARING
SKIES... EXPECT MVFR STRATUS TO RETURN AFTER 7Z TONIGHT...OVER
ALL BUT KABI. LIGHT MVFR FOG POSSIBLE TOWARDS MORNING WITH WET
VEGETATION. COULD SEE VISIBILITY DIPS INTO IFR...BUT SHOULD BRIEF
IF THEY OCCUR. CIGS RISE TO VFR BY LATE MORNING.
04
PREV DISCUSSION... /ISSUED 340 PM CDT SAT JUN 15 2013/
SHORT TERM...
CURRENTLY...VIS SATELLITE IMAGERY SHOWS AT LEAST TWO MCV/S IN OR
NEAR OUR CWA. ONE CAN BE SEEN TURNING OVER THE NORTHWEST CORNER OF
THE CWA...AND ANOTHER ONE IS MOVING NORTHWARD INTO CROCKETT AND
SONORA COUNTIES. THE SOUTHERN MCV APPEARS TO BE AIDING IN SCATTERED
NEW CONVECTIVE DEVELOPMENT SOUTH OF SAN ANGELO THIS AFTERNOON. AT
THE SAME TIME...A CU FIELD TO THE WEST OF THE CWA CAN BE SEEN
EVAPORATING FROM WEST TO EAST AS THE MAIN UPPER TROUGH MOVES EAST.
DEPENDING ON HOW FAST THE MAIN TROUGH CAN EXIT THE AREA...WE MAY
STILL SEE A REASONABLE CHANCE FOR ADDITIONAL CONVECTION LATER
TONIGHT AS THE MAIN TROUGH AXIS MOVES ACROSS THE AREA. HIGH
RESOLUTION MODELS AND THE GFS SEEM TO PICK UP ON THIS SHOWING
ADDITIONAL QPF ACROSS OUR SOUTHERN AREAS LATER TONIGHT. EXPECT
CHANCES TO FINALLY START TO DIMINISH MORE SUBSTANTIALLY AFTER
MIDNIGHT TONIGHT. AND IF ANY CLEARING OCCURS AS THE TROUGH AXIS
MOVES EAST...WE MIGHT EVEN SEE SOME PATCHY FOG IN WESTERN AREAS
WHERE HEAVIER PRECIPITATION FELL.
TEMPERATURES WILL BE SIMILAR TONIGHT TO LAST NIGHT WITH LOWS IN THE
UPPER 60S TO LOWER 70S. EXPECT WARMER TEMPERATURES ACROSS THE AREA
TOMORROW AS WE WILL SEE MUCH MORE SUNSHINE...AND NO RAINFALL. HAVE
TRIMMED POPS BACK IN THE NORTHWEST AS MOST OF THE POSSIBLE
CONVECTION TOMORROW AIS NOW EXPECTED TO OCCUR FARTHER WEST NEAR THE
TX/NM BORDER.
LONG TERM...
/SUNDAY NIGHT THROUGH SATURDAY/
COLD FRONT MAY BRING A CHANCE OF SHOWERS AND THUNDERSTORMS...
MAINLY TO THE BIG COUNTRY...MONDAY NIGHT INTO TUESDAY NIGHT.
AN UPPER RIDGE WILL BUILD IN FROM THE SOUTH TO NORTH THIS WEEK.
RIDGE WILL BE WEAK ENOUGH EARLY THIS WEEK...TO ALLOW DEVELOPMENT
OF SCATTERED THUNDERSTORMS ALONG A COLD FRONT...MONDAY NIGHT AND
TUESDAY. THE FRONT IS EXPECTED TO MOVE INTO THE THE RED RIVER
VALLEY MONDAY NIGHT...MOVING PERHAPS AS FAR SOUTH AS THE I-20
CORRIDOR. WHILE THE BEST CHANCE OF RAIN WILL BE IN THE BIG
COUNTRY... CANNOT RULE OUT POTENTIAL FOR STORM OUTFLOW TO PUSH
FARTHER SOUTH INTO THE CONCHO VALLEY AND HEARTLAND...LATE MONDAY
NIGHT INTO TUESDAY.
GFS SURFACE BASED CAPES INCREASE TO 1500-2000 J/KG OVER THE BIG
COUNTRY MONDAY INTO WEDNESDAY...SO A STRONG OR SEVERE
THUNDERSTORM POSSIBLE. HOWEVER UPPER DYNAMICS WILL BE NORTH OF
THE REGION...SO DO NOT EXPECT ORGANIZED SEVERE WEATHER. UPPER
RIDGING WILL BE BUILDING DIRECTLY OVER THE REGION THE SECOND HALF
OF NEXT WEEK...ENDING RAIN CHANCES AND BRINGING WARMER
TEMPERATURES.
04
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 70 94 73 94 71 / 10 10 10 20 30
SAN ANGELO 69 95 71 95 72 / 10 10 10 10 20
JUNCTION 71 93 71 93 71 / 20 5 5 10 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
04/HUBER
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1109 AM CDT FRI JUN 14 2013
.UPDATE...
HAVE ADDED 10 POPS OVER THE FAR WESTERN COUNTIES THIS AFTERNOON FOR
ISOLATED CONVECTION POTENTIAL. A FEW LIGHT SHOWERS HAVE ALREADY
PASSED THROUGH MILLS AND LAMPASAS COUNTIES THIS MORNING AND
EXPECT SOME ADDITIONAL ACTIVITY DURING THE AFTERNOON HOURS. 75
&&
.AVIATION...
FOR THE 12Z TAFS...VFR CONDITIONS ARE EXPECTED THROUGH THE VALID
FORECAST PERIOD. LOW CHANCES OF SHOWERS AND THUNDERSTORMS LATE
THIS AFTERNOON AND ON SATURDAY ARE THE PRIMARY FORECAST CONCERNS.
A WEAK BUT LARGE UPPER LOW REMAINS IN PLACE NEAR DEL RIO...AND IS
EXPECTED TO MOVE NORTH THROUGHOUT THE DAY TODAY. AREA AIRPORTS ARE
EXPECTED TO REMAIN UNDER THE INFLUENCE OF AN UPPER LEVEL RIDGE
WHICH IS EXPECTED TO SLIDE SOUTHEAST OVER NORTH TX TODAY AND
SHOULD KEEP US DRY THROUGH SATURDAY MORNING.
WE WILL HAVE TO CAREFULLY MONITOR AREA TAF SITES FOR SHOWERS AND
THUNDERSTORMS DEVELOPING FURTHER EAST THAN MODEL GUIDANCE
EXPLICITLY FORECASTS THOUGH. MORNING RUNS OF THE RAP AND NAM BOTH
INDICATE THAT WE HAVE VERY LITTLE TO NO CAP REMAINING FOR STORMS
OVER THE DFW AREA AND WACO BY 23Z. THIS DOES NOT MEAN WE WILL GET
STORMS...HOWEVER ANY WEAK FORCING FOR ASCENT MAY BE ENOUGH TO SET
OFF SOME /SURPRISE/ SHOWER OR THUNDERSTORM ACTIVITY NEAR OR ON TOP
OF AREA AIRPORTS LATE THIS AFTERNOON INTO THE EVENING HOURS.
CHANCES OF THIS ARE TOO LOW TO DO ANYTHING BUT MENTION THE
POSSIBILITY IN THE DISCUSSION AT THIS TIME.
WE WILL HAVE A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS TOMORROW
AFTERNOON AT ALL AREA AIRPORTS AS THE UPPER LOW IS EXPECTED TO
MOVE NORTHEAST OVER NORTH TX. THE BEST CHANCE OF STORMS LOOKS TO
OCCUR AFTER 18Z AT THIS TIME...WHICH IS BEYOND THE CURRENT VALID
FORECAST PERIOD. CAVANAUGH
&&
.PREV DISCUSSION... /ISSUED 422 AM CDT FRI JUN 14 2013/
CHANGES IN THE WEATHER PATTERN SHOULD BRING SOME MUCH NEED RAIN TO
NORTH TEXAS THIS WEEKEND THROUGH EARLY NEXT WEEK. THE UPPER LEVEL
RIDGE THAT HAS DOMINATED NORTH TEXAS WEATHER THIS PAST WEEK WILL
MOVE EAST TO THE MISSISSIPPI VALLEY REGION WHILE A WEAK CLOSED LOW...
CURRENTLY CENTERED NEAR THE BIG BEND...OPENS UP AND MOVES EAST.
PRECIPITATION ASSOCIATED WITH THE UPPER LOW SHOULD REMAIN
WEST/SOUTHWEST OF NORTH TEXAS TODAY AS LARGE SCALE SUBSIDENCE
CONTINUES OVER THE REGION. HOWEVER...SCATTERED SHOWERS AND
THUNDERSTORMS WILL BE POSSIBLE ACROSS THE WESTERN SECTIONS OF
NORTH TEXAS AS EARLY AS SATURDAY MORNING AND ACROSS THE REMAINDER
OF REGION SATURDAY AFTERNOON AND EVENING. MARGINAL INSTABILITY AND
SHEAR WILL KEEP MOST IF NOT ALL STORMS BELOW SEVERE LIMITS...BUT
PRECIPITABLE WATER VALUES AROUND 2 INCHES WILL RESULT EFFICIENT
RAIN PRODUCING STORMS. THERE WILL BE MODERATE STEERING FLOW SO
FLASH FLOODING IS NOT EXPECTED. THE UPPER TROUGH AXIS WILL MOVE
EAST OF THE REGION OVERNIGHT SATURDAY AND PRECIPITATION CHANCES
WILL END.
BRIEF RIDGING ALOFT IS EXPECTED SUNDAY. HOWEVER...THE RIDGE IS
PROGGED TO FLATTEN SUNDAY NIGHT AS AN UPPER TROUGH DEEPENS AND
MOVES EAST ACROSS THE NORTHERN AND CENTRAL PLAINS. A COLD FRONT
WILL MOVE SOUTHWARD ACROSS THE CENTRAL PLAINS BEHIND THE EASTWARD
MOVING UPPER TROUGH. THE FRONT SHOULD CROSS THE RED RIVER ON
MONDAY AND STALL OVER NORTH TEXAS UNTIL WEDNESDAY. THE ECMWF SOLUTION
AND GFS ARE STARTING TO COME IN LINE WITH EACH OTHER REGARDING THE
STRENGTH OF THE COLD FRONT AND POSITION OF THE ASSOCIATED PRECIP.
HAVE DECIDED TO RAISE POPS IN THE MONDAY THROUGH WEDNESDAY TIME
FRAME...MAINLY BASED ON THE RUN TO RUN CONSISTENCY OF THE ECMWF.
THE BEST RAIN CHANCES SHOULD BE ALONG AND JUST NORTH OF THE COLD
FRONT...ESPECIALLY TUESDAY WHEN A SHORT WAVE ROTATES THROUGH THE
REGION AND PROVIDES ADDITIONAL FORCING. WILL KEEP THE HIGHEST POPS
ACROSS THE NORTHERN HALF OF THE REGION BASED ON THE EXPECTED
POSITION OF THE FRONT. PRECIPITATION CHANCES SHOULD DECREASE FROM
WEST TO EAST TUESDAY NIGHT THROUGH WEDNESDAY AS THE SHORT WAVE
TROUGH MOVES EAST AND THE COLD FRONT BEGINS TO LIFT NORTHWARD IN
RESPONSE TO A DEVELOPING LEE TROUGH.
UPPER LEVEL HIGH PRESSURE WILL BUILD BACK OVER NORTH TEXAS THE END
OF NEXT WEEK THROUGH THE WEEKEND AND RESULT IN WARMER AND RAIN
FREE CONDITIONS.
AFTER ANOTHER HOT DAY TODAY WITH HIGHS IN THE MIDDLE AND UPPER 90S...
TEMPERATURES SHOULD BE A BIT COOLER SATURDAY DUE TO INCREASED
CLOUD COVER AND PRECIPITATION. HOTTER TEMPS WILL BRIEFLY RETURN SUNDAY
DUE TO MORE SUN AND BUILDING HIGH PRESSURE. HOWEVER...SLIGHTLY COOLER
TEMPERATURES ARE ON TAP MONDAY THROUGH WEDNESDAY DUE TO THE
PASSAGE OF THE COLD FRONT AND EXPECTED PRECIP. AFTERNOON HIGHS
MONDAY THROUGH WEDNESDAY WILL RANGE FROM THE UPPER 80S IN THE
NORTH TO THE MID 90S IN THE SOUTH. HIGH TEMPERATURES THE REMAINDER
OF NEXT WEEK WILL BE GENERALLY IN THE MIDDLE 90S. 79
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 97 77 94 77 97 / 0 5 30 10 10
WACO, TX 96 75 95 75 95 / 0 5 20 10 10
PARIS, TX 97 74 92 73 93 / 0 5 20 20 10
DENTON, TX 98 74 94 75 96 / 0 5 30 10 10
MCKINNEY, TX 97 75 93 73 94 / 0 5 30 20 10
DALLAS, TX 98 78 95 77 95 / 0 5 20 10 10
TERRELL, TX 97 76 94 74 94 / 0 5 20 10 10
CORSICANA, TX 97 75 93 75 93 / 0 5 20 10 10
TEMPLE, TX 94 73 93 74 93 / 5 5 20 10 10
MINERAL WELLS, TX 96 74 94 72 95 / 5 10 30 10 10
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/75
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
709 AM CDT FRI JUN 14 2013
.AVIATION...
FOR THE 12Z TAFS...VFR CONDITIONS ARE EXPECTED THROUGH THE VALID
FORECAST PERIOD. LOW CHANCES OF SHOWERS AND THUNDERSTORMS LATE
THIS AFTERNOON AND ON SATURDAY ARE THE PRIMARY FORECAST CONCERNS.
A WEAK BUT LARGE UPPER LOW REMAINS IN PLACE NEAR DEL RIO...AND IS
EXPECTED TO MOVE NORTH THROUGHOUT THE DAY TODAY. AREA AIRPORTS ARE
EXPECTED TO REMAIN UNDER THE INFLUENCE OF AN UPPER LEVEL RIDGE
WHICH IS EXPECTED TO SLIDE SOUTHEAST OVER NORTH TX TODAY AND
SHOULD KEEP US DRY THROUGH SATURDAY MORNING.
WE WILL HAVE TO CAREFULLY MONITOR AREA TAF SITES FOR SHOWERS AND
THUNDERSTORMS DEVELOPING FURTHER EAST THAN MODEL GUIDANCE
EXPLICITLY FORECASTS THOUGH. MORNING RUNS OF THE RAP AND NAM BOTH
INDICATE THAT WE HAVE VERY LITTLE TO NO CAP REMAINING FOR STORMS
OVER THE DFW AREA AND WACO BY 23Z. THIS DOES NOT MEAN WE WILL GET
STORMS...HOWEVER ANY WEAK FORCING FOR ASCENT MAY BE ENOUGH TO SET
OFF SOME /SURPRISE/ SHOWER OR THUNDERSTORM ACTIVITY NEAR OR ON TOP
OF AREA AIRPORTS LATE THIS AFTERNOON INTO THE EVENING HOURS.
CHANCES OF THIS ARE TOO LOW TO DO ANYTHING BUT MENTION THE
POSSIBILITY IN THE DISCUSSION AT THIS TIME.
WE WILL HAVE A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS TOMORROW
AFTERNOON AT ALL AREA AIRPORTS AS THE UPPER LOW IS EXPECTED TO
MOVE NORTHEAST OVER NORTH TX. THE BEST CHANCE OF STORMS LOOKS TO
OCCUR AFTER 18Z AT THIS TIME...WHICH IS BEYOND THE CURRENT VALID
FORECAST PERIOD.
CAVANAUGH
&&
.PREV DISCUSSION... /ISSUED 422 AM CDT FRI JUN 14 2013/
CHANGES IN THE WEATHER PATTERN SHOULD BRING SOME MUCH NEED RAIN TO
NORTH TEXAS THIS WEEKEND THROUGH EARLY NEXT WEEK. THE UPPER LEVEL
RIDGE THAT HAS DOMINATED NORTH TEXAS WEATHER THIS PAST WEEK WILL
MOVE EAST TO THE MISSISSIPPI VALLEY REGION WHILE A WEAK CLOSED LOW...
CURRENTLY CENTERED NEAR THE BIG BEND...OPENS UP AND MOVES EAST.
PRECIPITATION ASSOCIATED WITH THE UPPER LOW SHOULD REMAIN
WEST/SOUTHWEST OF NORTH TEXAS TODAY AS LARGE SCALE SUBSIDENCE
CONTINUES OVER THE REGION. HOWEVER...SCATTERED SHOWERS AND
THUNDERSTORMS WILL BE POSSIBLE ACROSS THE WESTERN SECTIONS OF
NORTH TEXAS AS EARLY AS SATURDAY MORNING AND ACROSS THE REMAINDER
OF REGION SATURDAY AFTERNOON AND EVENING. MARGINAL INSTABILITY AND
SHEAR WILL KEEP MOST IF NOT ALL STORMS BELOW SEVERE LIMITS...BUT
PRECIPITABLE WATER VALUES AROUND 2 INCHES WILL RESULT EFFICIENT
RAIN PRODUCING STORMS. THERE WILL BE MODERATE STEERING FLOW SO
FLASH FLOODING IS NOT EXPECTED. THE UPPER TROUGH AXIS WILL MOVE
EAST OF THE REGION OVERNIGHT SATURDAY AND PRECIPITATION CHANCES
WILL END.
BRIEF RIDGING ALOFT IS EXPECTED SUNDAY. HOWEVER...THE RIDGE IS
PROGGED TO FLATTEN SUNDAY NIGHT AS AN UPPER TROUGH DEEPENS AND
MOVES EAST ACROSS THE NORTHERN AND CENTRAL PLAINS. A COLD FRONT
WILL MOVE SOUTHWARD ACROSS THE CENTRAL PLAINS BEHIND THE EASTWARD
MOVING UPPER TROUGH. THE FRONT SHOULD CROSS THE RED RIVER ON
MONDAY AND STALL OVER NORTH TEXAS UNTIL WEDNESDAY. THE ECMWF SOLUTION
AND GFS ARE STARTING TO COME IN LINE WITH EACH OTHER REGARDING THE
STRENGTH OF THE COLD FRONT AND POSITION OF THE ASSOCIATED PRECIP.
HAVE DECIDED TO RAISE POPS IN THE MONDAY THROUGH WEDNESDAY TIME
FRAME...MAINLY BASED ON THE RUN TO RUN CONSISTENCY OF THE ECMWF.
THE BEST RAIN CHANCES SHOULD BE ALONG AND JUST NORTH OF THE COLD
FRONT...ESPECIALLY TUESDAY WHEN A SHORT WAVE ROTATES THROUGH THE
REGION AND PROVIDES ADDITIONAL FORCING. WILL KEEP THE HIGHEST POPS
ACROSS THE NORTHERN HALF OF THE REGION BASED ON THE EXPECTED
POSITION OF THE FRONT. PRECIPITATION CHANCES SHOULD DECREASE FROM
WEST TO EAST TUESDAY NIGHT THROUGH WEDNESDAY AS THE SHORT WAVE
TROUGH MOVES EAST AND THE COLD FRONT BEGINS TO LIFT NORTHWARD IN
RESPONSE TO A DEVELOPING LEE TROUGH.
UPPER LEVEL HIGH PRESSURE WILL BUILD BACK OVER NORTH TEXAS THE END
OF NEXT WEEK THROUGH THE WEEKEND AND RESULT IN WARMER AND RAIN
FREE CONDITIONS.
AFTER ANOTHER HOT DAY TODAY WITH HIGHS IN THE MIDDLE AND UPPER 90S...
TEMPERATURES SHOULD BE A BIT COOLER SATURDAY DUE TO INCREASED
CLOUD COVER AND PRECIPITATION. HOTTER TEMPS WILL BRIEFLY RETURN SUNDAY
DUE TO MORE SUN AND BUILDING HIGH PRESSURE. HOWEVER...SLIGHTLY COOLER
TEMPERATURES ARE ON TAP MONDAY THROUGH WEDNESDAY DUE TO THE
PASSAGE OF THE COLD FRONT AND EXPECTED PRECIP. AFTERNOON HIGHS
MONDAY THROUGH WEDNESDAY WILL RANGE FROM THE UPPER 80S IN THE
NORTH TO THE MID 90S IN THE SOUTH. HIGH TEMPERATURES THE REMAINDER
OF NEXT WEEK WILL BE GENERALLY IN THE MIDDLE 90S.
79
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 97 77 94 77 97 / 0 5 30 10 10
WACO, TX 96 75 95 75 95 / 0 5 20 10 10
PARIS, TX 97 74 92 73 93 / 0 5 20 20 10
DENTON, TX 98 74 94 75 96 / 0 5 30 10 10
MCKINNEY, TX 97 75 93 73 94 / 0 5 30 20 10
DALLAS, TX 98 78 95 77 95 / 0 5 20 10 10
TERRELL, TX 97 76 94 74 94 / 0 5 20 10 10
CORSICANA, TX 97 75 93 75 93 / 0 5 20 10 10
TEMPLE, TX 94 73 93 74 93 / 0 5 20 10 10
MINERAL WELLS, TX 96 74 94 72 95 / 0 10 30 10 10
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS SAN ANGELO TX
1159 PM CDT THU JUN 13 2013
.DISCUSSION...
SEE AVIATION SECTION.
&&
.AVIATION...
CHALLENGING AVIATION FORECAST WITH THE 00Z MODELS SHOWING A
WETTER PATTERN FOR WEST CENTRAL TEXAS. GIVEN HOW MOIST THE
AIRMASS IS BECOMING...ALONG WITH THE FORECAST TRACK OF THE UPPER
LOW AND EXTENT OF CONVECTIVE ACTIVITY ACROSS OUR AREA EARLIER IN
THE EVENING...A WETTER SOLUTION APPEARS MORE REASONABLE. WITH THIS
IN MIND...INTRODUCING VCSH AND LOWER CEILINGS SOONER IN THE DAY AT
KSOA...KJCT... KSJT AND KBBD. WITH UNCERTAINTY IN HOW EXTENSIVE
THE SHOWERS/THUNDERSTORM COVERAGE WILL BE...ALONG WITH HOW LOW THE
CEILINGS AND VISIBILITIES WILL BE WITH THE CONVECTION... KEEPING
THE CEILINGS VFR WITH THE 06Z TAF PACKAGE. CEILING AND VISIBILITY
REDUCTIONS INTO THE MVFR CATEGORY WILL BE POSSIBLE IN THE LOCALLY
HEAVY RAIN WHICH ACCOMPANIES THE CONVECTION. LOCALLY GUSTY WINDS
WILL ALSO BE POSSIBLE IN AND NEAR THUNDERSTORMS. SOUTH TO
SOUTHEAST WINDS ARE EXPECTED THROUGH THE TAF PERIOD.
19
&&
.PREV DISCUSSION... /ISSUED 1024 PM CDT THU JUN 13 2013/
UPDATE...
ADJUSTED POPS AND TEMPERATURES FOR THE REMAINDER OF THE NIGHT.
DISCUSSION...
CONVECTION HAS ALL BUT ENDED ACROSS THE AREA WITH ONLY SOME LIGHT
SHOWERS REMAINING ACROSS CROCKETT COUNTY. UPPER LOW CURRENTLY NEAR
THE BIG BEND WILL LIFT SLOWLY NORTH ACROSS THE TRANS PECOS REGION
THROUGH FRIDAY MORNING. LATEST NAM AND HRRR SHOW SOME ADDITIONAL
CONVECTION LIFTING NORTH ACROSS SOUTHWEST COUNTIES TOWARDS
DAYBREAK SO WILL KEEP INHERITED SLIGHT CHANCE TO LOW END CHANCE
POPS GOING ROUGHLY SOUTH AND WEST OF A SAN ANGELO TO JUNCTION LINE
FOR THE REMAINDER OF THE NIGHT. OVERNIGHT LOW TEMPERATURES WERE
ALSO RAISED A FEW DEGREES BASED ON TRENDS AND EXPECTED CLOUD
COVER.
PREV DISCUSSION... /ISSUED 655 PM CDT THU JUN 13 2013/
DISCUSSION...
SEE AVIATION SECTION.
AVIATION...
SCATTERED SHOWERS AND THUNDERSTORMS OVER CENTRAL AND SOUTHERN PARTS
OF WEST CENTRAL TEXAS ARE MOVING TO THE NORTHWEST...AND WILL POTENTIALLY
AFFECT THE KSJT AND KBBD TAF SITES DURING THE FIRST HOUR IN THE TAF
PERIOD /00-01Z/. GUSTY WINDS 35-40 KT ARE POSSIBLE IN AND NEAR THE
STORMS...AND A FEW OF THE STORMS WILL LIKELY CONTAIN FREQUENT
LIGHTNING. BRIEF REDUCTIONS IN CLOUD CEILING AND VISIBILITY ARE
POSSIBLE IN THE LOCALLY HEAVY RAIN WHICH ACCOMPANIES THIS
CONVECTION. THE SHOWERS AND STORMS WILL GRADUALLY DISSIPATE LATE
THIS EVENING. CLOUD COVER WILL DECREASE DURING THE NIGHT WITH VFR
CONDITIONS EXPECTED TO PREVAIL. LATE NIGHT INCREASE IN BOUNDARY
LAYER MOISTURE LOOKS MARGINAL FOR LOW CLOUD DEVELOPMENT ACROSS OUR
SOUTHERN COUNTIES. HOLDING OFF WITH A LOW CLOUD MENTION FOR NOW
AND WILL REVISIT THIS WITH THE NEXT /06Z/ TAF PACKAGE. A VFR-BASED
CUMULUS FIELD IS EXPECTED TO DEVELOP DURING THE DAY THURSDAY.
SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP PRIMARILY
DURING THE AFTERNOON... WITH THE BETTER COVERAGE ANTICIPATED
ACROSS ROUGHLY WEST OF A SWEETWATER TO SAN ANGELO TO SONORA LINE.
SOME OF THE SHOWERS MAY DEVELOP BY MID-TO-LATE MORNING THURSDAY
ACROSS THE SOUTHWESTERN PART OF WEST CENTRAL TEXAS /SOUTHWEST OF A
MERTZON TO SONORA LINE/. AT THIS TIME...CARRYING VCSH FOR ALL AREA
TAF SITES EXCEPT KABI FOR THURSDAY AFTERNOON. MAY ADJUST THE
TIMING WITH THE NEXT TAF PACKAGE. SIMILAR TO TODAY...WILL HAVE A
POSSIBILITY OF GUSTY WINDS...FREQUENT LIGHTNING...AND BRIEF CLOUD
CEILING AND VISIBILITY REDUCTIONS IN THE LOCALLY HEAVY RAINFALL
WHICH ACCOMPANIES SOME OF THE STORMS.
19
PREV DISCUSSION... /ISSUED 605 PM CDT THU JUN 13 2013/
UPDATE...
WIDLEY SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH
MID EVENING SOUTH OF THE BIG COUNTRY. POPS WERE ADDED ACROSS
EASTERN PORTIONS OF THE CONCHO VALLEY...HEARTLAND AND NORTHWEST
HILL COUNTRY THROUGH MID EVENING. SEVERE WEATHER IS NOT EXPECTED
BUT STORMS WILL BE CAPABLE OF BRIEF HEAVY RAINFALL...WIND GUSTS TO
45 MPH AND DANGEROUS CLOUD TO GROUND LIGHTNING. NO OTHER CHANGES
MADE AT THIS TIME.
PREV DISCUSSION... /ISSUED 331 PM CDT THU JUN 13 2013/
SHORT TERM...
/TONIGHT THROUGH FRIDAY/
AN UPPER LOW IS SITUATED OVER THE BIG BEND REGION EARLY THIS
AFTERNOON AT THE BASE OF AN UPPER RIDGE THAT EXTENDS NORTH THROUGH
THE PLAINS STATES. PER LATEST RADAR...A LARGE AREA OF ASSOCIATED
SHOWERS AND THUNDERSTORMS EXTENDS FROM THE BIG BEND COUNTRY EAST
TO THE TEXAS GULF COAST. THIS AREA OF SHOWERS IS SLOWLY MAKING ITS
WAY NORTH AND SHOULD ENTER OUR SOUTHERN TIER OF COUNTIES LATER
THIS AFTERNOON. THE CENTER OF THE UPPER LOW IS FORECAST TO MOVE
NORTH ON A TRACK JUST WEST OF THE FORECAST AREA TO A POSITION OVER
THE NORTHERN PANHANDLE BY LATE TOMORROW. THE BULK OF SHOWERS
ASSOCIATED WITH THIS SYSTEM WILL REMAIN WEST OF THE CWA WITH THE
BEST CHANCE OF RAINFALL FOR OUR AREA BEING THE SOUTHWESTERN CWA
THROUGH TONIGHT AND THROUGH THE DAY TOMORROW...WITH POPS
DECREASING FROM SOUTHWEST TO NORTHEAST. AFTERNOON HIGHS TOMORROW
WILL REFLECT THE EXPECTED CLOUD COVER AND RAINFALL WITH MID 80S
OVER THE SOUTHWESTERN CWA TO THE MID 90S OVER THE NORTHEASTERN
CWA...WHICH SHOULD BE RAIN FREE WITH LESS CLOUD COVER. LOOKING FOR
MORNING LOWS TOMORROW IN THE LOWER 70S ACROSS ALL OF THE FORECAST
AREA.
LONG TERM...
/FRIDAY NIGHT THROUGH THURSDAY/
AN UPPER LEVEL LOW CONTINUES TO SPIN IN NORTH CENTRAL MEXICO
TODAY. THIS WILL MOVE NORTH INTO WEST TEXAS THROUGH
SATURDAY...BEFORE MOVING OFF TO THE NORTHEAST SATURDAY NIGHT. HAVE
KEPT IN SLIGHT CHANCE TO CHANCE POPS FOR THE AREA FRIDAY NIGHT
THROUGH SATURDAY. HAVE KEPT HIGHER POPS TO THE WEST AS THE ECMWF
CONTINUES TO BE THE LONE MODEL WITH THE HIGHEST PROBABILITY OF
PRECIPITATION ACROSS THE CENTRAL PART OF THE FORECAST AREA. WITH
PRECIPITABLE WATERS INCREASING TO NEAR 1.75 INCHES...AND THE SLOW
MOVING NATURE OF THE STORMS...WE MAY SEE SOME LOCALLY HEAVY
RAINFALL AND MINOR FLOODING UNDER THE STRONGER STORMS. IN
ADDITION...DANGEROUS CLOUD TO GROUND LIGHTNING AND GUSTY WINDS
WILL BE POSSIBLE...BUT WIDESPREAD SEVERE WEATHER IS NOT EXPECTED.
FOLLOWING OUR RAIN CHANCES THROUGH SATURDAY...A WEAK RIDGING TO
ZONAL PATTERN IS EXPECTED TO SET UP ACROSS THE SOUTHWEST U.S. THIS
WILL BRING WARMER WEATHER BACK INTO THE AREA THROUGH THE REST OF
THE FORECAST. HOWEVER...HEIGHTS/THICKNESSES ARE NOT EXPECTED TO
REACH THE SAME LEVELS AS WERE EXPERIENCED EARLIER THIS WEEK...SO
HIGHS SHOULD STAY BELOW TRIPLE DIGIT VALUES FOR THE MOST PART.
HAVE GONE AHEAD AND INTRODUCED SOME SLIGHT CHANCE POPS FOR
NORTHERN AREAS MONDAY NIGHT INTO TUESDAY OF NEXT WEEK. MEDIUM
RANGE GUIDANCE AGREES THAT A COLD FRONT WILL MOVE SOUTH INTO THE
RED RIVER VALLEY OR JUST SOUTH OF THERE BY EARLY NEXT WEEK AS A
RESULT OF A SFC HIGH PRESSURE BUILDING ACROSS THE CENTRAL/SOUTHERN
PLAINS BEHIND AN UPPER LEVEL LOW MOVING THROUGH THE GREAT LAKES.
THE ECMWF AND CANADIAN MODELS CARRY PRECIPITATION FARTHER SOUTH
INTO THE CONCHO VALLEY AND HEARTLAND...BUT WILL HOLD POPS NORTH OF
THE INTERSTATE 20 CORRIDOR FOR NOW AS FLOW ALOFT IS EXPECTED TO BE
FAIRLY WEAK AND WESTERLY IN OUR AREA...AND JUST HOW FAR SOUTH THE
FRONT WILL MAKE IT IS QUESTIONABLE THIS TIME OF THE YEAR.
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 73 90 71 92 73 / 5 10 20 30 10
SAN ANGELO 72 89 71 93 73 / 30 30 30 30 10
JUNCTION 72 86 71 92 72 / 20 30 20 20 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
133 PM EDT FRI JUN 14 2013
.SYNOPSIS...
COOL HIGH PRESSURE WILL GRADUALLY BUILD INTO THE AREA TONIGHT INTO
FRIDAY BRINGING IN MUCH DRIER AIR INTO THE WEEKEND. MOISTURE WILL
START TO RETURN ON SUNDAY AS THE HIGH MOVES OFFSHORE FOLLOWED BY
A COLD FRONT EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 900 AM EDT FRIDAY...
MADE SOME MINOR ADJUSTMENTS TO CLOUD COVER AND TEMPERATURES
TODAY. NAM AND RAP STILL SHOWED SOME LIGHT SHOWERS WITH THE WEAK
SHORTWAVE THAT DROPS SOUTH ACROSS THE MID ATLANTIC REGION.
MOISTURE REMAINS QUITE SHALLOW BUT LAPSE RATES SUPPORT LIGHT
POP MENTION ACROSS THE NORTH.
AS OF 410 AM EDT FRIDAY...
UPPER TROF MOVES EAST OF THE FORECAST AREA THIS MORNING. A WEAK
SHORT WAVE TRACKS DOWN THE WEST SIDE OF THE TROF AND ACROSS THE
MID ATLANTIC REGION TODAY. TEMPERATURES ALOFT ARE COOL ENOUGH FOR
LARGE LAPSE RATES BUT MOISTURE IS LIMITED. BUFKIT FORECAST
SOUNDINGS SHOWED MOISTURE CONFINED TO SHALLOW LAYER BETWEEN 900
AND 800 MB. MODELS SHOWED BEST POTENTIAL FOR SHOWERS IN THE
WESTERN UPSLOPE AREAS OF SOUTHEAST WEST VIRGINIA AND EAST OF HOT
SPRINGS AND LYNCHBURG THIS AFTERNOON. ANY PRECIPITATION WILL BE
LIGHT.
THE STRATOCUMULUS AND ANY SHOWERS THAT DEVELOP THIS AFTERNOON WILL
DISSIPATE THIS EVENING WITH THE LOSS OF HEATING. 850 MB START OUT
AROUND 35 KNOTS THIS MORNING AND DIMINISH TO LESS THAN 20 KNOTS BY
THIS EVENING. HIGH PRESSURE BUILDS IN TONIGHT AND WILL BE CENTERED
OVER WEST VIRGINIA BY SATURDAY MORNING. SURFACE WINDS WILL
DECOUPLE...AND WITH A CLEAR SKY EXPECT VERY FAVORABLE CONDITIONS
FOR COOLING. SHELTERED VALLEYS IN THE WEST MAY DROP JUST BELOW 50
DEGREES OVERNIGHT.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
AS OF 326 AM EDT FRIDAY...
SUNDAY WILL PRESENT THE FIRST OPPORTUNITY FOR SHOWERS...MAINLY WEST
OF THE BLUE RIDGE. AN UPPER DISTURBANCE HEADING OUR WAY IS RATHER
SHEARED AND WEAK...ALSO INSTABILITY ISN`T THAT GREAT. THINKING THE
MODELS MAY BE OVERDOING THE AMOUNT OF PRECIP AND COVERAGE SO WENT
A LITTLE LESS THAN GUIDANCE POPS AND DELAYED MOST OF THE RAIN
UNTIL LATE AFTERNOON. COMPARED TO LAST NIGHT`S RUNS...THERE IS A
DEEPER TROUGH OVER THE EASTERN US MONDAY WITH A STRONGER UPPER LOW
OVER SE CANADA...ALSO THE UPPER RIDGE OVER THE SOUTHEASTERN STATES
IS FLATTER. THIS CONFIGURATION WILL SEND A COLD FRONT IN OUR
DIRECTION MONDAY NIGHT AND TUESDAY...WITH MORE SHOWERS AND SOME
STORMS OUT AHEAD OF THE BOUNDARY FOR A CLOUDY YET WARM AND HUMID
MONDAY.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 1215 PM EDT THURSDAY...
HIGH PRESSURE WILL BE OFF THE SOUTHEAST COAST WHILE INCREASING
HUMIDITY AND PIECES OF SHORTWAVE ENERGY MOVE ACROSS THE AREA AHEAD
OF A FRONT. THE PATTERN SUGGESTS THAT MON-TUE WILL HAVE THE BETTER
THREAT OF SHOWERS/STORMS WITH THE FRONT SHIFTING SOUTHEAST OF US BY
WEDNESDAY. HIGH PRESSURE BUILDS IN BEHIND THIS FRONT OVER THE GREAT
LAKES SOUTH INTO THE TN VALLEY WEDNESDAY AND THURSDAY. THE FRONT
WILL STAY HUNG UP ACROSS THE SOUTHEAST SO THERE IS AN OUTSIDE SHOT
THAT SOME OF OUR SRN CWA COUNTIES COULD SEE A FEW SHOWERS WED OR
THU...ALTHOUGH FOR NOW LEFT IT MAINLY DRY. TEMPS ABOVE NORMAL EARLY
BECOME MORE NORMAL POST FRONTAL PASSAGE...WITH HUMIDITY DROPPING
SOME BY WED NIGHT-THU.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 130 PM EDT FRIDAY...
SCATTERED TO BROKEN STRATOCUMULUS AT ROA/BCB/LWB/BLF AND THE
WESTERN UPSLOPE AREAS WILL GRADUALLY DISSIPATE THIS AFTERNOON.
NORTH SURFACE WINDS GUSTING UP TO 20 KNOTS THIS AFTERNOON WILL
DIMINISH THIS EVENING INTO TONIGHT.
HIGH PRESSURE WILL BUILD IN TONIGHT AND SATURDAY RESULTING IN VFR
WEATHER. WITH LIGHT WINDS AND LOW LEVEL MOISTURE ALLOWED
FOR PATCHY FOG AT KLWB OVERNIGHT INTO SATURDAY MORNING.
LOW LEVEL SOUTHERLY FLOW RETURNS ON SUNDAY AHEAD OF ANOTHER FRONT
MOVING INTO THE MIDWEST/GREAT LAKES. MAY SEE FOG AT THE TYPICAL
LOCATIONS SUNDAY MORNING... KLWB/KBCB...OTHERWISE VFR. THE
RETURN OF MOISTURE WILL BRING ISOLATED STORMS TO THE MOUNTAINS
SUNDAY AFTERNOON...WITH BETTER COVERAGE ACROSS THE REGION MONDAY
AND TUESDAY AHEAD/ALONG AND APPROACHING COLD FRONT.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/KK
SHORT TERM...KM/WP
LONG TERM...WP
AVIATION...AMS/KK
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
903 AM EDT FRI JUN 14 2013
.SYNOPSIS...
COOL HIGH PRESSURE WILL GRADUALLY BUILD INTO THE AREA TONIGHT INTO
FRIDAY BRINGING IN MUCH DRIER AIR INTO THE WEEKEND. MOISTURE WILL
START TO RETURN ON SUNDAY AS THE HIGH MOVES OFFSHORE FOLLOWED BY
A COLD FRONT EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 900 AM EDT FRIDAY...
MADE SOME MINOR ADJUSTMENTS TO CLOUD COVER AND TEMPERATURES
TODAY. NAM AND RAP STILL SHOWED SOME LIGHT SHOWERS WITH THE WEAK
SHORTWAVE THAT DROPS SOUTH ACROSS THE MID ATLANTIC REGION.
MOISTURE REMAINS QUITE SHALLOW BUT LAPSE RATES SUPPORT LIGHT
POP MENTION ACROSS THE NORTH.
AS OF 410 AM EDT FRIDAY...
UPPER TROF MOVES EAST OF THE FORECAST AREA THIS MORNING. A WEAK
SHORT WAVE TRACKS DOWN THE WEST SIDE OF THE TROF AND ACROSS THE
MID ATLANTIC REGION TODAY. TEMPERATURES ALOFT ARE COOL ENOUGH FOR
LARGE LAPSE RATES BUT MOISTURE IS LIMITED. BUFKIT FORECAST
SOUNDINGS SHOWED MOISTURE CONFINED TO SHALLOW LAYER BETWEEN 900
AND 800 MB. MODELS SHOWED BEST POTENTIAL FOR SHOWERS IN THE
WESTERN UPSLOPE AREAS OF SOUTHEAST WEST VIRGINIA AND EAST OF HOT
SPRINGS AND LYNCHBURG THIS AFTERNOON. ANY PRECIPITATION WILL BE
LIGHT.
THE STRATOCUMULUS AND ANY SHOWERS THAT DEVELOP THIS AFTERNOON WILL
DISSIPATE THIS EVENING WITH THE LOSS OF HEATING. 850 MB START OUT
AROUND 35 KNOTS THIS MORNING AND DIMINISH TO LESS THAN 20 KNOTS BY
THIS EVENING. HIGH PRESSURE BUILDS IN TONIGHT AND WILL BE CENTERED
OVER WEST VIRGINIA BY SATURDAY MORNING. SURFACE WINDS WILL
DECOUPLE...AND WITH A CLEAR SKY EXPECT VERY FAVORABLE CONDITIONS
FOR COOLING. SHELTERED VALLEYS IN THE WEST MAY DROP JUST BELOW 50
DEGREES OVERNIGHT.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
AS OF 326 AM EDT FRIDAY...
SUNDAY WILL PRESENT THE FIRST OPPORTUNITY FOR SHOWERS...MAINLY WEST
OF THE BLUE RIDGE. AN UPPER DISTURBANCE HEADING OUR WAY IS RATHER
SHEARED AND WEAK...ALSO INSTABILITY ISN`T THAT GREAT. THINKING THE
MODELS MAY BE OVERDOING THE AMOUNT OF PRECIP AND COVERAGE SO WENT
A LITTLE LESS THAN GUIDANCE POPS AND DELAYED MOST OF THE RAIN
UNTIL LATE AFTERNOON. COMPARED TO LAST NIGHT`S RUNS...THERE IS A
DEEPER TROUGH OVER THE EASTERN US MONDAY WITH A STRONGER UPPER LOW
OVER SE CANADA...ALSO THE UPPER RIDGE OVER THE SOUTHEASTERN STATES
IS FLATTER. THIS CONFIGURATION WILL SEND A COLD FRONT IN OUR
DIRECTION MONDAY NIGHT AND TUESDAY...WITH MORE SHOWERS AND SOME
STORMS OUT AHEAD OF THE BOUNDARY FOR A CLOUDY YET WARM AND HUMID
MONDAY.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 1215 PM EDT THURSDAY...
HIGH PRESSURE WILL BE OFF THE SOUTHEAST COAST WHILE INCREASING
HUMIDITY AND PIECES OF SHORTWAVE ENERGY MOVE ACROSS THE AREA AHEAD
OF A FRONT. THE PATTERN SUGGESTS THAT MON-TUE WILL HAVE THE BETTER
THREAT OF SHOWERS/STORMS WITH THE FRONT SHIFTING SOUTHEAST OF US BY
WEDNESDAY. HIGH PRESSURE BUILDS IN BEHIND THIS FRONT OVER THE GREAT
LAKES SOUTH INTO THE TN VALLEY WEDNESDAY AND THURSDAY. THE FRONT
WILL STAY HUNG UP ACROSS THE SOUTHEAST SO THERE IS AN OUTSIDE SHOT
THAT SOME OF OUR SRN CWA COUNTIES COULD SEE A FEW SHOWERS WED OR
THU...ALTHOUGH FOR NOW LEFT IT MAINLY DRY. TEMPS ABOVE NORMAL EARLY
BECOME MORE NORMAL POST FRONTAL PASSAGE...WITH HUMIDITY DROPPING
SOME BY WED NIGHT-THU.
&&
.AVIATION /13Z FRIDAY THROUGH TUESDAY/...
AS OF 725 AM EDT FRIDAY...
SCATTERED TO BROKEN STRATOCUMULUS AT ROA/BCB/LWB/BLF AND THE
WESTERN UPSLOPE AREAS WILL GRADUALLY DISSIPATE THIS MORNING.
NORTHWEST SURFACE WINDS GUSTING UP TO 20 KNOTS WILL TURN TO THE
NORTH AND WIND SPEEDS WILL DIMINISH BY AFTERNOON.
HIGH PRESSURE WILL BUILD IN TODAY AND SATURDAY RESULTING IN VFR
WEATHER. GRIDDED LAMP GUIDANCE SUGGESTED LIFR FOG IN THE
GREENBRIER VALLEY AT THE KLWB AIRPORT LATE TONIGHT. THE SKY WILL
BE CLEAR WITH A CALM WIND BUT AIR MASS WILL BE DRY. CONFIDENCE NOT
HIGH ENOUGH AT THIS TIME TO INCLUDE IN THE TAF.
LOW LEVEL SOUTHERLY FLOW RETURNS ON SUNDAY AHEAD OF ANOTHER FRONT
MOVING INTO THE MIDWEST/GREAT LAKES. MAY SEE FOG AT THE TYPICAL
LOCATIONS SUNDAY MORNING... KLWB/KBCB...OTHERWISE VFR. THE
RETURN OF MOISTURE WILL BRING ISOLATED STORMS TO THE MOUNTAINS
SUNDAY AFTERNOON...WITH BETTER COVERAGE ACROSS THE REGION MONDAY
AND TUESDAY AHEAD/ALONG AND APPROACHING COLD FRONT.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/KK
SHORT TERM...KM/WP
LONG TERM...WP
AVIATION...AMS/JH
AREA FORECAST DISCUSSION
NWS SPOKANE WA
428 AM PDT Fri Jun 14 2013
.SYNOPSIS...
Scattered mountain showers are expected today as temperatures still
remain on the cool side. Drier and much warmer weather can be
expected for the weekend. The next weather system will arrive by
Monday and bring more showery and cool weather for much of the
upcoming work week.
&&
.DISCUSSION...
Today and tonight...The Inland NW will be under the influence of an
exiting upper level trough of low pressure and cold air for the
next 24 hours. Currently this trough resides across eastern
Washington. Most of the daytime convection has diminished, but
radar does show some light shower activity associated with a few
upper level impulses and terrain. Of the upper level disturbances,
there are two main ones that we will be monitoring. The first is
within the base of the upper level trough and is pivoting across
the northeast Oregon and the Clearwater mountains into southwest
Montana with a band of light showers and embedded thunderstorms.
This area continues to pull away from our region and may brush our
southeast borders with mid level clouds and a few early morning
sprinkles. The other impulse is seen on satellite dropping south
from BC down the Okanogan valley. The Kelowna radar does show
light showers, and if they hold together, they could reach Omak
and Republic early this morning. Updated the early morning grids
to reflect this trend. The HRRR does pick up on these light
showers and spreads them from the Okanogan Valley and Highlands,
toward Colville and Sandpoint area early Friday morning as the
upper level trough axis shifts east. Daytime heating and surface
based instability will be enhanced within the upper level trough
axis which will be over northeast Washington and north Idaho
during the afternoon and early evening. Cape values will reach
near 400 j/kg, not as steep as yesterday but enough for the
potential of a couple embedded thunderstorms especially over the
mountains. Meanwhile, a more stable, dry westerly flow will
develop across the western zones. The instability will quickly
decrease after mid evening as an upper level ridge of high
pressure builds into the region with drying and clearing Friday
night. Although temperatures will moderate gradually today and
tonight, they will still be cooler than normal. /rfox.
Saturday and Saturday night: As the Low exits the region a ridge will
build into Eastern Washington...bringing drier and warmer weather
to much of the forecast area. Weak diffluence and daytime heating
will begin to affect the Cascades by Saturday afternoon, leading
to potential showers or isolated thunderstorm along the crest of
the Cascades. The next Low pressure will move into position just
of the coast of northern BC. /JDC
Sunday through Monday...Model agreement is good and consistent
over previous runs in depicting an increasingly moist and deep
southerly flow regime over the forecast area as a new upper level
low slowly approaches the forecast area off the Pacific. This
pattern strongly argues fro increasing temperatures each day...as
will as the return of a perceptible convective threat...probably
beginning Sunday mainly over the Cascades and on Monday broadening
out to include a chance of showers and thunderstorms over the
mountains ringing the basin...but also a smaller threat of a stray
shower or afternoon thunderstorm over the basin. Moisture and
instability will be increasing...but so far models do not sense
any especially stimulating short wave or disturbance necessary to
trigger widespread convection. An unsettled early summer-like
regime would best characterize this period of the forecast.
Monday night through Thursday...This period will cover the passage
directly aloft of the incoming closed low. For the last few days
the EC and GFS have been consistent and in reasonable agreement
in tracking this upper low directly across the forecast area. Two
distinct events are becoming increasingly likely during this
evolution...the first will be another day of increased convective
activity as the increasingly moist southerly flow continues to
impact the region on Tuesday...showers and thunderstorms will be
hit-and-miss but highly likely to be prowling most of the
forecast area justifying solid chance pops...with high
temperatures cooler than previous days but only down to around
seasonal normal values.
By Wednesday and Thursday there is an increased likelihood that a
much wetter and cooler pattern will develop as the low center
passes directly over the region...and on at least one of these
days...at this time Wednesday looks like the best bet but
Thursday also a possibility...or maybe both days...a downright wet dense
shower/stratiform rain event associated with a deformation band
will develop probably over the east and north reaches of the
forecast area. Model details are still a little nebulous that far
out but in good agreement with the overall pattern which
historically implies a wetter solution than climatology would
suggest. /Fugazzi
&&
.AVIATION...
12Z TAFS: One disturbance is pulling away from the KWS/KPUW this
morning and will see skies tempo clear this morning. Meanwhile a
secondary disturbance will bring mid and high level clouds to the
KGEG-KCOE area after 15z with isolated showers. AFter 19z, surface
based instability will enhance the cumulus clouds and the best
chance for showers and thunderstorms look to be north and east of
KGEG-KCOE. Drier westerly flow will be found from KEAT to KMWH.
Expect the convection to diminish by 02z with clearing and VFR
conditions overnight. /rfox.
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 68 47 77 53 84 56 / 20 10 0 0 10 10
Coeur d`Alene 67 42 77 50 85 53 / 20 20 0 0 10 10
Pullman 68 38 77 47 84 49 / 20 10 0 0 0 10
Lewiston 75 48 85 54 91 56 / 20 0 0 0 0 10
Colville 74 45 81 49 88 54 / 40 20 0 0 20 20
Sandpoint 68 39 77 45 85 48 / 30 30 0 0 10 10
Kellogg 67 43 73 50 82 54 / 40 10 0 0 10 10
Moses Lake 77 46 86 57 90 59 / 10 0 0 0 10 20
Wenatchee 75 52 85 63 89 61 / 0 0 0 10 10 20
Omak 75 45 83 54 87 57 / 20 0 0 10 20 20
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
242 AM PDT Fri Jun 14 2013
.SYNOPSIS...
Scattered mountain showers are expected today as temperatures still
remain on the cool side. Drier and much warmer weather can be
expected for the weekend. The next weather system will arrive by
Monday and bring more showery and cool weather for much of the
upcoming work week.
&&
.DISCUSSION...
Today and tonight...The Inland NW will be under the influence of an
exiting upper level trough of low pressure and cold air for the
next 24 hours. Currently this trough resides across eastern
Washington. Most of the daytime convection has diminished, but
radar does show some light shower activity associated with a few
upper level impulses and terrain. Of the upper level disturbances,
there are two main ones that we will be monitoring. The first is
within the base of the upper level trough and is pivoting across
the northeast Oregon and the Clearwater mountains into southwest
Montana with a band of light showers and embedded thunderstorms.
This area continues to pull away from our region and may brush our
southeast borders with mid level clouds and a few early morning
sprinkles. The other impulse is seen on satellite dropping south
from BC down the Okanogan valley. The Kelowna radar does show
light showers, and if they hold together, they could reach Omak
and Republic early this morning. Updated the early morning grids
to reflect this trend. The HRRR does pick up on these light
showers and spreads them from the Okanogan Valley and Highlands,
toward Colville and Sandpoint area early Friday morning as the
upper level trough axis shifts east. Daytime heating and surface
based instability will be enhanced within the upper level trough
axis which will be over northeast Washington and north Idaho
during the afternoon and early evening. Cape values will reach
near 400 j/kg, not as steep as yesterday but enough for the
potential of a couple embedded thunderstorms especially over the
mountains. Meanwhile, a more stable, dry westerly flow will
develop across the western zones. The instability will quickly
decrease after mid evening as an upper level ridge of high
pressure builds into the region with drying and clearing Friday
night. Although temperatures will moderate gradually today and
tonight, they will still be cooler than normal. /rfox.
Saturday and Saturday night: As the Low exits the region a ridge will
build into Eastern Washington...bringing drier and warmer weather
to much of the forecast area. Weak diffluence and daytime heating
will begin to affect the Cascades by Saturday afternoon, leading
to potential showers or isolated thunderstorm along the crest of
the Cascades. The next Low pressure will move into position just
of the coast of northern BC. /JDC
Sunday through Monday...Model agreement is good and consistent
over previous runs in depicting an increasingly moist and deep
southerly flow regime over the forecast area as a new upper level
low slowly approaches the forecast area off the Pacific. This
pattern strongly argues fro increasing temperatures each day...as
will as the return of a perceptible convective threat...probably
beginning Sunday mainly over the Cascades and on Monday broadening
out to include a chance of showers and thunderstorms over the
mountains ringing the basin...but also a smaller threat of a stray
shower or afternoon thunderstorm over the basin. Moisture and
instability will be increasing...but so far models do not sense
any especially stimulating short wave or disturbance necessary to
trigger widespread convection. An unsettled early summer-like
regime would best characterize this period of the forecast.
Monday night through Thursday...This period will cover the passage
directly aloft of the incoming closed low. For the last few days
the EC and GFS have been consistent and in reasonable agreement
in tracking this upper low directly across the forecast area. Two
distinct events are becoming increasingly likely during this
evolution...the first will be another day of increased convective
activity as the increasingly moist southerly flow continues to
impact the region on Tuesday...showers and thunderstorms will be
hit-and-miss but highly likely to be prowling most of the
forecast area justifying solid chance pops...with high
temperatures cooler than previous days but only down to around
seasonal normal values.
By Wednesday and Thursday there is an increased likelihood that a
much wetter and cooler pattern will develop as the low center
passes directly over the region...and on at least one of these
days...at this time Wednesday looks like the best bet but
Thursday also a possibility...or maybe both days...a downright wet dense
shower/stratiform rain event associated with a deformation band
will develop probably over the east and north reaches of the
forecast area. Model details are still a little nebulous that far
out but in good agreement with the overall pattern which
historically implies a wetter solution than climatology would
suggest. /Fugazzi
&&
.AVIATION...
06Z TAFS: Stronger showers and thunderstorms have ended this
evening. Some light shower activity will continue across the
Cascade crest, northeast mountains, and in the vicinity of
KLWS/PUW tonight. There is a possibility of patchy fog and/or
stratus/low cloud development from about 10Z on to 18Z for
KLWS/KCOE where more significant showers fell earlier, but
confidence is low. Drier conditions will prevail for all TAF
sites Friday with scattered showers possible for the Idaho
panhandle. /EK
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 68 47 77 53 84 56 / 20 10 0 0 10 10
Coeur d`Alene 67 42 77 50 85 53 / 20 20 0 0 10 10
Pullman 68 38 77 47 84 49 / 20 10 0 0 0 10
Lewiston 75 48 85 54 91 56 / 20 0 0 0 0 10
Colville 74 45 81 49 88 54 / 40 20 0 0 20 20
Sandpoint 68 39 77 45 85 48 / 30 30 0 0 10 10
Kellogg 67 43 73 50 82 54 / 40 10 0 0 10 10
Moses Lake 77 46 86 57 90 59 / 10 0 0 0 10 20
Wenatchee 75 52 85 63 89 61 / 0 0 0 10 10 20
Omak 75 45 83 54 87 57 / 20 0 0 10 20 20
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1035 PM CDT SAT JUN 15 2013
.UPDATE...
ISSUED AT 1035 PM CDT SAT JUN 15 2013
EVENING RAINS...LIGHT WINDS...AND CLEARING SKIES IS A GREAT RECIPE
FOR FOG. OBS ACROSS NORTHWEST WI DROPPED TO 1/4 MILE QUICKLY AFTER
CLOUDS DEPARTED. DRIER AIR ACROSS PARTS OF NORTHERN MN...BUT DON/T
THINK THAT/S GOING TO WORK IN OVERNIGHT. WITH THAT IN MIND...HAVE
ELECTED TO ISSUE A DENSE FOG ADVISORY FOR CLARK/TAYLOR COUNTIES IN
NORTHCENTRAL WI. FOG HAS NOT DEVELOPED YET...BUT THE CONDITIONS ARE
RIPE FOR IT...AND FOR DENSE FOG. CONDITIONS WILL BE MONITORED AND
ADJUSTMENTS MADE AS NEEDED. DON/T SEE THIS DENSE FOG POTENTIAL
BECOMING FORECAST AREA-WIDE AT THE MOMENT...BOUNDARY LAYER MOISTURE
NOT AS FAVORABLE.
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 330 PM CDT SAT JUN 15 2013
LATEST RADAR SHOWED A LINE OF SHOWERS AND ISOLATED THUNDERSTORM
MOVING ACROSS SOUTHEAST MINNESOTA AND NORTHEAST IOWA AND WAS
WEAKENING RAPIDLY AS IT APPROACHED THE MISSISSIPPI RIVER.
SCATTERED THUNDERSTORMS WERE ONGOING ACROSS PORTIONS OF NORTH
CENTRAL AND NORTHWEST WISCONSIN. SURFACE OBSERVATIONS INDICATED A
WEAK COLD FRONT EXTENDING FROM SUPERIOR WISCONSIN...SOUTH TO RED
WING MINNESOTA TO AROUND AUSTIN MINNESOTA AND WAS GRADUALLY MOVING
EAST. A WEAKENING MCV WAS MOVING ACROSS THE FORECAST AREA AND WAS
SUPPORTING THE SHOWER/STORM ACTIVITY.
LATEST MESOSCALE ANALYSIS SHOWS 1500 TO 2000 J/KG OF SURFACED
BASED CAPE LINGERING ACROSS MUCH OF THE FORECAST AREA WITH AROUND
100 J/KG OF CIN. WILL HAVE TO KEEP A VERY CLOSE EYE ON THE
CLEARING BEHIND THE MCV TO SEE IF ADDITIONAL SHOWERS AND STORMS
WILL DEVELOP ALONG THE COLD FRONT. 0-6KM SHEAR IS INCREASING
BEHIND THIS FEATURE AS A 500 MB JET SAGS SOUTH INTO THE AREA. THE
FORECAST AREA ALSO IN PROXIMITY TO THE RIGHT ENTRANCE REGION OF A
250 MB JET STRETCHING FROM EASTERN SOUTH DAKOTA THROUGH CENTRAL
MINNESOTA INTO CENTRAL ONTARIO. CANNOT RULE OUT AN ISOLATED STRONG
TO PERHAPS SEVERE THUNDERSTORM LATE THIS AFTERNOON. CURRENTLY
THERE ISN/T MUCH FOR CUMULUS DEVELOPMENT ALONG THE BOUNDARY IN THE
WAKE OF THE MCV SO THINKING OVERALL SEVERE THREAT IS QUICKLY
DIMINISHING. THE COLD FRONT SLIDES SOUTH OF THE FORECAST AREA THIS
EVENING AS HIGH PRESSURE BUILDS IN TONIGHT INTO SUNDAY MORNING.
PLAN ON QUIET AND PLEASANT WEATHER ON SUNDAY WITH HIGH
TEMPERATURES CLIMBING INTO THE LOWER TO MID 80S UNDER PARTLY TO
MOSTLY SUNNY SKIES.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 330 PM CDT SAT JUN 15 2013
A TROUGH IS EXPECTED TO DIVE SOUTHEAST OUT OF SOUTHERN
MANITOBA/CANADA LATE SUNDAY NIGHT THROUGH MONDAY. ALSO...A COLD
FRONT WILL SLIDE SOUTH JUST AHEAD OF THE TROUGH. THE FRONT LOOKS TO
MOVE FROM NORTH TO SOUTH ACROSS THE FORECAST AREA MONDAY AFTERNOON
INTO MONDAY EVENING. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
DEVELOP LATE SUNDAY NIGHT AND CONTINUE INTO MONDAY AS THE FRONT
AND UPPER TROUGH MOVES THROUGH THE REGION. IF THE SYSTEM SLOWS AND
INSTABILITY CAN BUILD AHEAD OF THE SYSTEM ON MONDAY...A FEW STRONG
TO SEVERE STORMS ARE POSSIBLE. FORECAST SOUNDINGS INDICATE A
RATHER DRY SUB CLOUD LAYER...WITH AN INVERTED V LOOK TO THE
SOUNDING. 0-6 KM BULK SHEAR VALUES OF 30 TO 35 KTS...AND 0-3KM
MUCAPE VALUES IN THE 1200 TO 1500 J/KG ALSO SUPPORT THE POTENTIAL
FOR SEVERE THUNDERSTORMS. THINKING THAT THUNDERSTORMS MONDAY
AFTERNOON MAY HAVE THE POTENTIAL TO PRODUCE DAMAGING WIND GUSTS
AND POSSIBLY LARGE HAIL. THE FRONT MOVES SOUTH OF THE FORECAST
AREA MONDAY EVENING AND SURFACE HIGH PRESSURE BUILDS IN QUICKLY IN
ITS WAKE. NORTHWEST FLOW ALOFT THEN SETS UP ACROSS THE UPPER
MIDWEST TUESDAY THROUGH WEDNESDAY AS A RIDGE BUILDS OVER THE
CENTRAL CONUS. WILL HAVE TO KEEP A CLOSE WATCH ON EMBEDDED
SHORTWAVES WITHIN THE FLOW...WHICH HAVE THE POTENTIAL TO PRODUCE
SHOWERS AND THUNDERSTORMS. THINKING THE SURFACE HIGH SHOULD WIN
OUT AND PROVIDE QUIET WEATHER TUESDAY INTO WEDNESDAY. PLAN ON
HIGHS ON TUESDAY IN THE LOWER TO MID 70S...THEN WARMING SLIGHTLY
ON WEDNESDAY WITH HIGHS CLIMBING INTO THE UPPER 70S. THE UPPER
RIDGE STARTS TO BREAK DOWN THURSDAY THROUGH FRIDAY WITH SEVERAL
EMBEDDED SHORTWAVES MOVING THROUGH IT. WARM SOUTHERLY FLOW SETS UP
AT THE SURFACE ON THURSDAY AS THE HIGH SLIDES OFF TO THE EAST AND
A SURFACE TROUGH DEVELOPS OVER THE CENTRAL/NORTHERN PLAINS. AN
ACTIVE PERIOD IS IN STORE FOR THE FORECAST AREA STARTING LATE
THURSDAY AND POTENTIALLY LASTING INTO THE WEEKEND. LOOKING AT THE
ECMWF SOLUTIONS FOR FRIDAY...A SEVERE WEATHER EVENT MAY OCCUR. A
LOT OF DETAILS TO SORT OUT YET...BUT THIS IS THE TIMEFRAME WHEN
CAPE AND SHEAR PROFILES WOULD SUPPORT SEVERE THUNDERSTORMS.
ALSO...A SHORTWAVE TROUGH IS EXPECTED TO MOVE ACROSS THE AREA AND
COULD TRIGGER THE SHOWERS/STORMS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1035 PM CDT SAT JUN 15 2013
EXPECT CLEAR SKIES FOR THE REST OF THE NIGHT AS WEAK HIGH PRESSURE
BUILDS IN. DECOUPLING WINDS LEAD TO THOUGHTS OF FOG. LIGHTER SFC
WINDS AT KLSE...BUT RAP BUFKIT SOUNDINGS KEEP IT STIRRED NEAR 10 KTS
BY 200 FT. BOUNDARY LAYER DOESN/T APPEAR OVERLY MOIST...BUT T/TD
SPREAD AT KLSE IS 5 AS OF 10 PM. SEE SOME POTENTIAL THERE. BEST
AREAS FOR FOG WILL BE WHERE IT RAINS EARLIER THIS EVENING...WHICH IS
MOSTLY AROUND THE I-94 CORRIDOR AND NORTH. LEANING TOWARD NOT ADDING
ANY BR/FG MENTION INTO TAFS AT THIS TIME...BUT WILL MONITOR TRENDS
CLOSELY AN ADD IF IT BECOMES MORE LIKELY.
LATER SUNDAY NIGHT...A BOUNDARY TO THE NORTH WILL SINK SOUTH WITH
SOME WEAK MOISTURE TRANSPORT ALONG IT. A FEW SHRA/TS COULD SPARK
ALONG THE BOUNDARY...AND COULD IMPACT KRST/KLSE AFTER 06Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...DENSE FOG ADVISORY UNTIL 9 AM CDT SUNDAY FOR WIZ017-029.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM....WETENKAMP
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
831 PM CDT SAT JUN 15 2013
.UPDATE...
CONVECTION FINALLY GOT GOING THIS EVENING...JUST TOOK A LOT LONGER
THAN JUST ABOUT ANY MODEL SIMULATED. THE MID LEVEL SHORTWAVE/SFC
LOW PRESSURE COMBO SHOWS UP NICELY IN SATELLITE AND RADAR IMAGERY
WITH A DISTINCT CIRCULATION MOVING EAST OF LA CROSSE. AT TIMES THE
STORMS HAVE GOTTEN SOME RESPECTABLE DEPTH WITH LONG RANGE HAIL
ESTIMATES PUSHING 1 1/2 INCHES. STORMS ARE STARTING TO INCREASE
ALONG THE TRAILING TROF BACK INTO IOWA. THE HRRR FILLS THIS AREA UP
WITH RAIN BEFORE MIDNIGHT AND WE COULD SEE A PERIOD OF HEAVY RAIN
ALONG THE SOUTHERN TIER OF COUNTIES. SEVERE THREAT LOOKS LIMITED
GIVEN THE DECREASING PARAMETERS AS WE HEAD INTO THE EVENING. THE
STORMS LOOK LIKE THEY ARE STRUGGLING AT THIS POINT. EXPECT MOST OF
THE STORMS TO EXIT TO THE SOUTH AND EAST BY MIDNIGHT OR 1 AM. THEN
CLEARING THROUGH THE REMAINDER OF THE NIGHT. WE MAY HAVE TO DEAL
WITH SOME FOG RIGHT AROUND SUNRISE WITH WEAK WINDS AND LINGERING
BOUNDARY LAYER MOISTURE.
&&
.AVIATION/06Z TAFS/...
THUNDERSTORMS WILL BE EXITING TO THE EAST OF WISCONSIN BY THE
BEGINNING OF THE TAF PERIOD AT 06Z. WE SHOULD SEE AREAS OF MVFR
CONDITIONS BEFORE SUNRISE ON SUNDAY DUE TO CLEARING SKIES...LIGHT
WINDS AND LINGERING MOISTURE NEAR GROUND LEVEL. THEN DRIER AIR
ARRIVES BRINGING MOSTLY CLEAR SKIES FOR THE DURATION OF THE TAF
PERIOD.
&&
.PREV DISCUSSION... /ISSUED 336 PM CDT SAT JUN 15 2013/
SHORT TERM...
TONIGHT AND SUNDAY...FORECAST CONFIDENCE...MEDIUM TO HIGH.
SHOWERS AND STORMS ASSOCIATED WITH IOWA/MN SHORT WAVE AND VORTICITY
MAX HAVE WEAKENED OVER IOWA. THIS SYSTEM APPEARS TO BE MOVING
EAST-NORTHEAST. TAIL END OF PRECIP OVER IOWA SHOWS SIGNS OF
SPLITTING AND BLOWING OUT...PER HRRR MODEL RUN AT 16Z. BEST MOISTURE
TRANSPORT WITH LOW LEVEL JET IS FROM THE WEST-SOUTHWEST OVER IOWA
AND ILLINOIS AND MISSOURI. PUTTING THIS ALL TOGETHER...WILL GO WITH
MORE SCATTERED WORDING FOR SHOWERS AND STORMS ACROSS SOUTHERN
WISCONSIN LATE THIS AFTERNOON AND EVENING. WE JUST DON/T SEE DEEP
MOIST CONVECTION AFFECTING ALL PARTS OF OUR COUNTY WARNING AREA AS
PREVIOUSLY THOUGHT PER OLDER MODEL RUNS. BASICALLY..IT LOOKS LIKE
THE PALMYRA SPLIT AGAIN. MODELS DO NOT GENERATE DECENT LOW LEVEL
JET...ONLY SOME 20 TO 25 KNOTS FROM THE WEST-SOUTHWEST. DEEP LAYER
SHEAR REMAINS BELOW 35 KNOTS. SO DO NOT ANTICIPATE SEVERE
STORMS...BUT SOME STRONG STORMS POSSIBLE GIVEN CAPE OF 700 TO 1300
J/KG IN FORECAST SOUNDINGS. THINGS GRADUALLY QUIET DOWN AFTER 1 AM
TONIGHT AFTER 850 AND 700 MB TROUGHS SLIDE EAST.
SUNDAY WILL BE QUIET AS UPPER LEVEL FLOW BECOMES WEST TO NORTHWEST
AND SURFACE HIGH PRESSURE MOVES EAST FROM NORTHERN PLAINS TO IOWA
AND ILLINOIS AREA. MODELS HAVE A DRY COLUMN FORECASTED...AND EXPECT
ONLY SOME DAYTIME SCATTERED CUMULUS CLOUDS WITH HEATING. MODELS HAVE
925 MB TEMPS IN +21C RANGE...WHICH SUGGESTS MAX TEMPS IN LOWER 80S.
SURFACE WINDS WILL BE WEST TO NORTHWEST 10 TO 20 MPH WITH DAYTIME
HEATING AND MIXING TO THE 850 MB LEVEL WHERE WIND SPEEDS WILL BE IN
THE 20 KNOT RANGE.
SUNDAY NIGHT THROUGH TUESDAY...FORECAST CONFIDENCE MEDIUM
A SHORTWAVE TROUGH WILL DROP SEWD FROM THE NRN PLAINS INTO MN AND
NRN WI FOR LATE SUN NT...AND THEN ACROSS WI MON AND MON NT. AT THE
SFC...A COLD FRONT WILL DROP SWD INTO CENTRAL WI BY EARLY MON
AFTERNOON AND THEN PROGRESS SWD TO THE IL BORDER BY EARLY MON
EVENING. IF A SUFFICIENT N-S PRESSURE GRADIENT DEVELOPS...A
PNEUMONIA FRONT WILL BE GENERATED AND SWEEP SSWWD ACROSS THE WRN
SHORE OF LAKE MI AND ERN WI...AS THE NAM INDICATES. TEMPS WILL
DROP FROM THE LOWER 80S INTO THE 50S LAKESIDE. IF THE PRESSURE
GRADIENT REMAINS WEAKER LIKE THE ECMWF OR GFS...MORE OF A GRADUAL
CHANGE WILL OCCUR IN THE WINDS AND TEMPS. THE CONVERGENCE ALONG
THE COLD FRONT ALONG WITH THE APPROACHING SHORTWAVE TROUGH SHOULD
PROVIDE A GOOD TRIGGER FOR CONVECTION AS WELL. THERE ARE FAIRLY
LARGE MLCAPE DIFFERENCES ON THE MODELS BUT BELIEVE AT LEAST 1000
J/KG WILL OCCUR WITH MDT DEEP LAYER SHEAR. THE TSTORMS WILL
HOWEVER QUICKLY MOVE EWD INTO THE COOLER AIR BEHIND THE FRONT
LIMITING ANY STRONG OR SVR POTENTIAL TO A QUICK PULSE STORM.
NELY WINDS AND COLD ADVECTION WILL THEN BRING A COOL BUT PLEASANT
TUESDAY WITH HIGH PRESSURE CENTERED OVER THE NRN GREAT LAKES. SOME
MODELS HAVE ANOTHER SHORTWAVE TROUGH DIVING SEWD FROM MN TOWARD IL
ON TUE WHICH WOULD BRING CLOUDS AND POSSIBLY LGT PCPN. BEST
COMBINATION OF LIFT AND MOISTURE HOWEVER MAY STAY JUST TO THE WEST
AND WILL KEEP DRY FOR NOW.
LONG TERM...
WEDNESDAY THROUGH SATURDAY...FORECAST CONFIDENCE MEDIUM
HIGH PRESSURE WILL PREVAIL OVER THE LOWER GREAT LAKES AND MID
ATLANTIC STATES WED AND THU WHILE LEE SIDE TROUGHING OCCURS OVER
THE HIGH PLAINS IN RESPONSE TO A LARGE UPPER LOW MOVING INTO THE
PACIFIC NW. SRN WI WILL REMAIN DRY WED-THU DUE TO THE CLOSE
PROXIMITY TO THE HIGH AND LOW ATMOSPHERIC MOISTURE...BUT WITH A
WARMING TREND ON LGT SLY WINDS AND FULL SUNSHINE.
TSTORM CHANCES TO THEN INCREASE AT THE END OF THE WEEK AS THE
TROUGH OF LOW PRESSURE MOVES EAST ACROSS THE PLAINS BUT WEAKENS AS
THE UPPER TROUGH DE-AMPLIFIES AND LIFTS MORE INTO CANADA. THIS
RESULTS IN AN APPROACHING WARM FRONT BECOMING STATIONARY OVER THE
AREA WITH WARM...HUMID...AND UNSTABLE CONDITIONS.
AVIATION/00Z TAFS/...
WEAK SURFACE LOW PRESSURE AND COLD FRONT FORECAST TO MOVE ACROSS
SOUTHERN WISCONSIN TONIGHT. SCATTERD BANDS OF SHOWERS AND STORMS
WILL MOVE WEST TO EAST ACROSS THE AREA. GENERALLY VFR CONDITIONS
EXPECTED OUTSIDE OF THE THUNDERSTORMS. UNDER THE STORMS VISIBILITIES
COULD DROP TO 3 TO 5 MILES WITH SOME FOG MIXED IN DUE TO DEWPOINTS
IN THE 60S. GUSTS TO 30 KNOTS POSSIBLE WITH THE STORMS.
MARINE....
NOT MUCH GOING ON WITH THE WINDS AND WAVES OVER THE NEARSHORE ZONES.
EAST TO SOUTHEAST ONSHORE FLOW SATURDAY AFTERNOON WILL TRANSITION TO
A SOUTH TO SOUTHWEST FLOW OVERNIGHT AS COLD FRONT APPROACHES. AFTER
THE WEAK COLD FRONT THE WINDS WILL BECOME OFFSHORE. THERE IS A 2 TO
4 HOUR WINDOW SATURDAY EVENING FOR FOG DUE TO COOL WATER TEMPS WITH
MOIST AIR OVER LAND MOVING OUT OVER THE LAKE...BUT NOT CONFIDENT TO
PUT THIS INTO FORECAST. UPDATE ON FORECAST WOULD BE NEEDED THIS
EARLY THIS EVENING IF IT STILL LOOKS LIKE IT WILL HAPPEN.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...DAVIS
TONIGHT/SUNDAY AND AVIATION/MARINE...KAPELA
SUNDAY NIGHT THROUGH SATURDAY...GEHRING
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
600 PM CDT FRI JUN 14 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 320 PM CDT FRI JUN 14 2013
LATEST WATER VAPOR IMAGERY SHOWED A RIDGE OVER THE THE UPPER
MIDWEST WITH EMBEDDED SHORTWAVES MOVING THROUGH IT. A TROUGH WAS
MOVING INTO EASTERN MONTANA/WYOMING GRADUALLY PUSHING
EAST/NORTHEAST. A SHORTWAVE WAS MOVING ACROSS WESTERN AND CENTRAL
IOWA...FUELING SHOWERS AND THUNDERSTORMS. SURFACE OBSERVATIONS
INDICATED LOW PRESSURE OVER NORTH CENTRAL NEBRASKA SHIFTING EAST.
A WARM FRONT WAS POSITIONED FROM EAST CENTRAL NEBRASKA...EAST
THROUGH SOUTHERN IOWA. A SECOND SURFACE LOW WAS TAKING SHAPE OVER
SOUTHERN SASKATCHEWAN...WITH A SURFACE TROUGH EXTENDING SOUTHWARD
THROUGH CENTRAL NORTH DAKOTA/SOUTH DAKOTA. HIGH PRESSURE WAS
CENTERED OVER LAKE SUPERIOR...MOVING EAST WITH SOUTH/SOUTHEAST WINDS
INCREASING ACROSS THE FORECAST AREA AND USHERING IN A SLIGHTLY
WARMER AND MOIST AIRMASS.
THE SURFACE TROUGH WILL CONTINUE TO ADVANCE EAST THIS EVENING AS THE
WARM FRONT FRONT LIFT INTO NORTHERN IOWA. A SHORTWAVE MOVING THROUGH
THE RIDGE WILL ENTER THE UPPER MISSISSIPPI RIVER VALLEY THIS
EVENING. MEANWHILE...850 MB MOISTURE TRANSPORT RAMPS UP ALONG AND
WEST OF THE INTERSTATE 35 CORRIDOR EARLY THIS EVENING THEN QUICKLY
FOCUSES EAST INTO THE FORECAST AREA. PERIODS OF SHOWERS AND
THUNDERSTORMS ARE EXPECTED OVER THE AREA THIS EVENING INTO THE
OVERNIGHT HOURS. THE FOCUS FOR THE HEAVIEST RAINFALL WILL BE OVER
NORTHERN IOWA INTO FAR SOUTHWEST WISCONSIN...WHERE THE STRONGEST 850
MB MOISTURE TRANSPORT FOCUSES INTO THE FRONT. PRECIPITABLE WATER
VALUES CLIMB INTO THE 1.5 TO 1.9 RANGE ACROSS MUCH OF THE FORECAST
AREA THIS EVENING AND HOVER THERE THROUGH MUCH OF THE OVERNIGHT.
ALSO...WARM CLOUD DEPTH INCREASES TO AROUND 4KM ACROSS MUCH OF THE
REGION. THE THUNDERSTORMS SHOULD BE EFFICIENT RAIN PRODUCERS...WITH
LOCALLY HEAVY RAINFALL POSSIBLE. THE SURFACE TROUGH SLIDES THROUGH
LATE TONIGHT FOR LOCATIONS NORTH OF INTERSTATE 90...BUT THE WARM
FRONT LINGERS OVER NORTHERN IOWA INTO FAR SOUTHWEST WISCONSIN AND
THE MOISTURE TRANSPORT CONTINUES TO FOCUS INTO IT. THIS SHOULD LEAD
TO REPEATED ROUNDS OF SHOWERS AND STORMS OVER THESE AREAS...LEADING
TO POTENTIAL FLASH FLOODING. AREAS THAT HAVE RECEIVED RECENT HEAVY
RAINFALL ARE AT GREATEST RISK OF SEEING FLASH FLOODING. CANNOT RULE
OUT AN ISOLATED SEVERE HAIL REPORT OR TWO GIVEN ELEVATED CAPE VALUES
APPROACHING 2000 J/KG VERY LATE TONIGHT INTO SATURDAY MORNING.
HOWEVER...SHEAR IS LIMITED AND WITH VERY HIGH FREEZING LEVELS IT
WILL TAKE UPDRAFT ROTATION TO GROW LARGE ENOUGH HAILSTONES TO
OVERCOME THE HIGHER FREEZING LEVELS. SHOWERS AND STORMS WILL BE
ONGOING EARLY SATURDAY MORNING...ESPECIALLY ALONG AND SOUTH OF
INTERSTATE 90. WEAK RIDGING MOVES IN IN WAKE OF THE FIRST ROUND OF
SHOWERS/STORMS MID MORNING ON SATURDAY THEN ANOTHER SHORTWAVE
MOVES IN LATE SATURDAY MORNING INTO EARLY SATURDAY AFTERNOON.
ANOTHER ROUND OF SHOWERS AND STORMS EXPECTED WITH THIS WAVE. AGAIN
THE STORMS WILL BE CAPABLE OF PRODUCING HEAVY RAINFALL. THE
SURFACE TROUGH LOOKS TO BE POSITIONED ALONG THE INTERSTATE 35
CORRIDOR AROUND 15Z SATURDAY MORNING...THEN PUSHES EAST THROUGH
THE FORECAST AREA DURING THE LATE MORNING AND AFTERNOON HOURS.
DEPENDING ON WHETHER OR NOT WE SEE SOME SUNSHINE/DESTABILIZATION
IN THE WAKE OF THE FIRST ROUND OF ACTIVITY. THERE IS THE
POSSIBILITY OF SEEING A FEW STRONG TO SEVERE STORMS DEVELOPING
ALONG THIS SURFACE TROUGH. 0-6KM BULK SHEAR INCREASES IN THE
AFTERNOON HOURS TO AROUND 30 KTS AS THE SHORTWAVE MOVES IN.
ALSO...FORECAST SOUNDINGS SUGGEST WE COULD SEE SURFACE BASED CAPE
VALUES CLIMB TO AROUND 2000 J/KG. THE SHEAR LOOKS TO LAG BEHIND
THE WAVE SO THIS WOULD BE A LIMITING FACTOR FOR SEVERE POTENTIAL.
THE HIGHEST CHANCES FOR SHOWERS AND STORMS SATURDAY AFTERNOON WILL
OVER NORTHEAST IOWA AND FAR SOUTHWEST WISCONSIN. THE STRONGEST
MOISTURE TRANSPORT FOCUSES INTO SOUTHERN AND EASTERN IOWA BY
SATURDAY AFTERNOON. ALSO...THE OVERNIGHT MCS ACTIVITY COULD HELP
PUSH THE WARM FRONT TO THE SOUTH. WILL HAVE TO KEEP A VERY CLOSE
EYE ON THE POSITION OF THE WARM FRONT ON SATURDAY. PLAN ON HIGH
TEMPERATURES ON SATURDAY IN THE MID TO UPPER 70S.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 320 PM CDT FRI JUN 14 2013
THE SURFACE TROUGH PUSHES EAST OF THE FORECAST AREA SATURDAY
EVENING. ANOTHER ROUND OF CONVECTION ALONG THE WARM FRONT LATE
SATURDAY AFTERNOON INTO SATURDAY EVENING OVER NORTHEAST IOWA AND FAR
SOUTHWEST WISCONSIN WILL HELP TO PUSH THE WARM FRONT BACK TO THE
SOUTH...CLOSER TO THE INTERSTATE 80 CORRIDOR. SHOWERS AND STORMS
SHOULD TAPER OFF AND DURING THE EVENING HOURS AND FOCUS
SOUTH/SOUTHEAST OF THE FORECAST AREA. WEAK HIGH PRESSURE THEN MOVES
INTO THE REGION WITH THE FORECAST AREA BETWEEN SYSTEMS SATURDAY LATE
NIGHT INTO SUNDAY. SUNDAY IS SHAPING UP TO BE A RATHER PLEASANT LATE
SPRING DAY. UNDER PARTLY SUNNY SKIES...PLAN ON HIGHS CLIMBING INTO
THE LOWER TO MID 80S. AN UPPER TROUGH THEN RACES SOUTHEAST SUNDAY
NIGHT OUT OF SOUTHERN MANITOBA/ONTARIO AND HEADS TOWARD THE FORECAST
AREA. THERE ARE SOME SLIGHT TIMING DIFFERENCES IN THE FORECAST
MODELS ON EXACTLY WHEN THE TROUGH WILL PASS THROUGH. CURRENT
THINKING IS THAT THE TROUGH SHOULD MOVE THROUGH LATE SUNDAY SUNDAY
NIGHT INTO MONDAY MORNING...BRINGING CHANCES FOR SHOWERS AND
THUNDERSTORMS TO THE AREA. THE TROUGH FINALLY EXITS THE REGION LATE
MONDAY AFTERNOON WITH HIGH PRESSURE BUILDING ACROSS THE REGION IN
ITS WAKE. QUIET NORTHWEST FLOW ALOFT AND SURFACE HIGH PRESSURE IN
PLACE WILL PROVIDE DRY AND QUIET WEATHER THROUGH AT LEAST WEDNESDAY.
FORECAST MODELS ARE SUGGESTING SOME WEAK IMPULSES WILL MOVE THROUGH
THE AREA LATE IN THE WEEK BRINGING SOME LOW CHANCES FOR SHOWERS AND
STORMS TO THE AREA. HOWEVER MODEL SOLUTIONS START TO DIVERGE BEYOND
THURSDAY SO HAVE LEANED TOWARD MODEL CONSENSUS BLEND. HIGH
TEMPERATURES ARE EXPECTED TO RANGE FROM THE 70S TO AROUND 80S
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 600 PM CDT FRI JUN 14 2013
CURRENT SHRA/TS OVER CENTRAL IA SHOULD CONTINUE TO MARCH
SOUTHEAST...PER RAP CORFIDI VECTORS. BROAD SWATH OF LOW LEVEL
SOUTH-NORTH RUNNING LOW LEVEL MOISTURE TRANSPORT WILL GRADUALLY
SHIFT EAST TONIGHT...TRANSITIONING ACROSS THE AREA. MEANWHILE...A
RIDGE OF INSTABILTY ALSO SHIFTS EAST...DIMINISHING SOMEWHAT WITH THE
LOSS OF DAYTIME HEATING. THIS UNSTABLE...MOIST AIR WILL SERVE AS THE
FUEL FOR SHRA/TS DEVELOPMENT. THE QUESTION...AND WHERE THE
UNCERTAINLY LIES...IS WHAT WILL SERVE AS THE KICKERS FOR PCPN.
LATEST WATERVAPOR IMAGERY HINTS AT BITS OF UPPER LEVEL ENERGY THAT
COULD SPIN ACROSS THE REGION TONIGHT. AT THE SFC...A WARM FRONT IS
EXPECTED TO LIFT INTO CENTRAL IA OVERNIGHT. BELIEVE IA IS THE MOST
LIKELY TO EXPERIENCE THE MOST WIDESPREAD SHRA/TS TONIGHT...VIA
LATEST HRRR. HOWEVER...NAM12 TRACKS A BATCH OF RAIN DIRECTLY ACROSS
KRST/KLSE THIS EVENING...WHILE THE ARXLAPS DEVELOPS AN APPRECIABLE
AMOUNT OF RAIN WITHIN THE MOISTURE TRANSPORT BETWEEN 03-06Z...AGAIN
OVER THE TAF SITES.
CONFIDENCE IS LOW IN JUST HOW ALL WILL EVOLVE. WILL TREND TOWARD
THE HRRR FOR NOW...BUT ANTICIPATE UPDATES WILL BE NEEDED AS
SATELLITE/RADAR TRENDS BECOME MORE APPARENT.
&&
.HYDROLOGY...THIS EVENING THROUGH SATURDAY EVENING
ISSUED AT 320 PM CDT FRI JUN 14 2013
HEAVY RAINFALL COULD LEAD TO FLASH FLOODING OVER PORTIONS OF
SOUTHEAST MINNESOTA INTO NORTHEAST IOWA THIS EVENING THROUGH
SATURDAY EVENING. THE AREAS OF GREATEST CONCERN ARE LOCATIONS THAT
RECEIVED HEAVY RAINFALL ON WEDNESDAY...SUCH AS PORTIONS OF DODGE
AND FILMORE COUNTIES IN SOUTHEAST MINNESOTA...AND MUCH OF
NORTHEAST IOWA ESPECIALLY FLOYD AND MITCHELL COUNTIES. 1 TO 2
INCHES OF RAINFALL ARE POSSIBLE BY SATURDAY EVENING. LOCALLY
HIGHER AMOUNTS ARE NOT OUT OF THE QUESTION UNDER ANY STRONGER
THUNDERSTORMS.
A LINE OF SHOWERS AND STORMS WILL TRACK ACROSS PORTIONS OF
NORTHEAST IOWA LATE THIS AFTERNOON INTO EARLY THIS EVENING.
SHOWERS AND THUNDERSTORMS WILL BECOME WIDESPREAD LATE THIS
EVENING INTO THE OVERNIGHT HOURS AS A WARM FRONT LIFTS INTO
NORTHERN IOWA AND MOISTURE TRANSPORT FOCUSES INTO THE FRONT.
ANOTHER ROUND OF SHOWERS AND STORMS ARE EXPECTED LATE SATURDAY
MORNING INTO SATURDAY AFTERNOON. THE THUNDERSTORMS TONIGHT THROUGH
SATURDAY WILL BE VERY EFFICIENT RAIN PRODUCERS WITH PRECIPITABLE
WATER VALUES OF 1.5 TO 1.9 INCHES AND WARM CLOUD DEPTHS HOVERING
AROUND 4000 METERS. WILL CONTINUE THE FLASH FLOOD WATCH THROUGH
SATURDAY EVENING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...FLASH FLOOD WATCH THROUGH SATURDAY EVENING FOR MNZ094-095.
IA...FLASH FLOOD WATCH THROUGH SATURDAY EVENING FOR IAZ008>010-018-
019-029-030.
&&
$$
SHORT TERM....WETENKAMP
LONG TERM.....WETENKAMP
AVIATION......RIECK
HYDROLOGY.....WETENKAMP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
105 PM CDT FRI JUN 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 329 AM CDT FRI JUN 14 2013
MAIN FORECAST FOCUS IS ON POTENTIAL FOR HEAVY RAIN/FLASH FLOODING
LATER TODAY THROUGH SATURDAY.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A HIGHLY AMPLIFIED PATTERN ACROSS NORTH AMERICA...CONSISTING
OF TROUGHING OVER ALBERTA AND IDAHO...RIDGING FROM THE SOUTHERN
PLAINS INTO MANITOBA...AND TROUGHING FROM SOUTHEAST CANADA SOUTHWARD
ALONG THE EAST COAST OF THE U.S.. THE FORECAST AREA LIES ON THE
SUBSIDENT SIDE OF THE RIDGING...RESULTING IN HIGH PRESSURE AT THE
SURFACE WHICH EXISTS OVER WISCONSIN. 00Z SOUNDINGS FROM MPX...GRB
AND DVN DEPICTED A DRY AIRMASS WITH THIS HIGH PRESSURE AREA WITH
PRECIPITABLE WATER VALUES OF 0.7-0.8 INCHES OR 80-90 PERCENT OF
NORMAL. THE DRY AIRMASS HAS HELPED KEEP SKIES MOSTLY CLEAR OVERNIGHT
AND WITH LIGHT WINDS...TEMPERATURES HAVE DROPPED INTO THE UPPER 40S
TO UPPER 50S. MEANWHILE...TO THE WEST UNDER AND WEST OF THE UPPER
RIDGE AXIS...MOISTURE HAS BEEN GRADUALLY ADVECTING NORTHWARD THROUGH
THE PLAINS ON A 30-45 KT 850MB JET PER VWP DATA. GOES DERIVED
PRECIPITABLE WATER SHOWED VALUES OF 1-1.5 INCHES ACROSS MUCH OF THE
PLAINS...HIGHEST ACROSS SOUTH CENTRAL NEBRASKA AND NORTH CENTRAL KS.
THIS MAXIMA WAS ALSO CORRELATED WITH THE REMNANTS OF AN MCS THAT
INITIATED OFF THE FRONT RANGE IN COLORADO YESTERDAY AFTERNOON. ALONG
WITH THE INCREASED MOISTURE...00Z RAOBS SHOWED 850MB TEMPS OF 16-21C
FROM RAPID CITY TO OMAHA AND TOPEKA...QUITE A BIT WARMER COMPARED TO
THE 10-13C AROUND THE FORECAST AREA. ALONG THE GRADIENT OF THIS
TEMPERATURE DIFFERENCE...A NARROW LINE OF SHOWERS AND THUNDERSTORMS
HAS BROKE OUT OVER SOUTHWEST MN INTO WESTERN IA.
OVER THE NEXT 24 HOURS...THE UPPER RIDGE AXIS OVER THE PLAINS IS
PROGGED TO SHIFT EAST OVER THE FORECAST AREA. THIS IS IN RESPONSE TO
THE TROUGH OVER IDAHO AND ALBERTA EJECTING NORTHEAST...AS WELL AS
FORMING A DEEP CLOSED LOW CIRCULATION OVER CENTRAL SASKATCHEWAN.
WHAT THIS MEANS FOR THE FORECAST AREA IS ALL OF THAT WARMER 850MB
AIR AND HIGHER PRECIPITABLE WATER UNDER THE UPPER RIDGE WILL MOVE
TOWARDS US. GIVEN THE WARM ADVECTION PATTERN...EXPECT CONCERN FOR
PRECIPITATION TO INCREASE. IN ADDITION...CONVECTIVELY INDUCED
SHORTWAVES FROM CONVECTION COMING OFF THE ROCKIES AND THE PLAINS
THIS MORNING...AND THOSE THAT FIRE THIS AFTERNOON...WILL ALSO PLAY A
ROLE AS THEY HEAD NORTHEAST AROUND THE UPPER RIDGE.
FOR TODAY...GENERAL CONSENSUS FROM THE MODELS IS FOR INCREASING
310-315K ISENTROPIC LIFT AND 700MB MOISTURE TRANSPORT TO COME ACROSS
THE FORECAST AREA DURING THE AFTERNOON. ANTICIPATING AN
ALTOSTRATUS/ACCAS DECK TO FORM AS A RESULT AND OVERSPREAD MUCH OF
THE AREA. THIS CAN ALREADY BE SEEN ALONG THE DAKOTAS/MN BORDER WHERE
THOSE SHOWERS AND THUNDERSTORMS HAVE BEEN OCCURRING. HAVE
CONTINUED THE MENTION OF SOME LOW PROBABILITIES FOR PRECIPITATION
WEST OF THE MS RIVER EARLY THIS AFTERNOON TO ACCOUNT FOR THIS SHOWER
POTENTIAL.
LATE IN THE AFTERNOON...SOMETHING TO WATCH IS THE 14.00Z NAM
SCENARIO WHICH DEPICTS A LARGER AMOUNT OF CONVECTION OVER SOUTH
CENTRAL MN AND NORTH CENTRAL IA...CLIPPING FAR WESTERN PORTIONS OF
THE FORECAST AREA. THE GFS/ECMWF/REGIONAL CANADIAN ARE VERY
SIMILAR...THOUGH QPF VALUES ARE NOT NEARLY AS HIGH WHICH MAY BE A
RESULT OF MODEL RESOLUTION. THE SITUATION APPEARS TO BE A RESULT OF
INCREASING 700-850MB MOISTURE TRANSPORT...ON THE LEADING EDGE OF THE
HIGHER PRECIPITABLE WATER VALUES OF 1.5-1.8 INCHES PER RAP COMING
INTO WESTERN IA...CAPE OF 1000 J/KG OR SO THAT IS UNCAPPED LIFTED
FROM 725MB...AND A POSSIBLE RIGHT ENTRANCE REGION OF A JET STREAK
TRACKING SOUTHEAST THROUGH WISCONSIN. SHOULD THIS PAN OUT...GIVEN
THE HIGH PRECIPITABLE WATER...THESE STORMS WILL BE HEAVY RAIN
PRODUCERS.
NAM/GFS/ECMWF/REGIONAL CANADIAN MOISTURE TRANSPORT FIELDS FROM
925-700MB ARE ALL IN AGREEMENT THAT THE STREAM SHIFTS NORTHEAST
TONIGHT...FOLLOWING THE UPPER RIDGE AXIS. THUS...THINKING THE
CONVECTION THAT FIRES LATE THIS AFTERNOON SHOULD SLOWLY PROGRESS
EASTWARD THROUGH THE FORECAST AREA. ADDITIONALLY...IT APPEARS THERE
IS A SECOND SURGE OF MOISTURE TRANSPORT COMING UP OUT OF KS INTO
CENTRAL IA OVERNIGHT...LIKELY FIRING MORE CONVECTION ON ITS NOSE
FROM NORTH CENTRAL INTO EASTERN IA. THE ECMWF HAS BEEN EXTREMELY
CONSISTENT RUN TO RUN WITH THIS.
ALTHOUGH INSTABILITY IS ADVECTING TOWARDS US ON THIS MOISTURE
TRANSPORT...THE INSTABILITY IS TALL AND SKINNY. WITH WARM CLOUD
DEPTHS APPROACHING 14 KFT...THINKING HEAVY RAIN WOULD BE THE MAIN
SEVERE WEATHER CONCERN. ADDITIONALLY...THE 2-7KM SHEAR WHICH IS MORE
REPRESENTATIVE OF THE INSTABILITY USED BY THE STORMS...IS LESS THAN
30 KTS. SEE THE HYDROLOGY SECTION BELOW FOR MORE ON THE IMPACTS FROM
THE PRECIPITATION. MAIN THING TO NOTE HERE IS THAT GIVEN THE MOIST
SOILS OVER PORTIONS OF NORTHEAST IA AND SOUTHEAST MN...ANY HEAVY
RAIN MAY CAUSE FLASH FLOODING...ESPECIALLY IN FLOYD AND MITCHELL
COUNTIES IN IA. THEREFORE...HAVE ISSUED FLASH FLOOD WATCHES FOR THE
MOST CONCERNING AREAS.
850MB TEMPERATURES ARE PROGGED TO STAY BETWEEN 10-13C TODAY. WITH
INCREASING CLOUDS...TEMPERATURES SHOULD END UP NEAR OR A LITTLE
BELOW YESTERDAY HIGHS. WARMER NIGHT ON TAP AS HIGHER DEWPOINTS MOVE
IN ACCOMPANYING THE HIGHER PRECIPITABLE WATER.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 329 AM CDT FRI JUN 14 2013
SATURDAY THROUGH MONDAY...
MODELS ARE IN GOOD AGREEMENT FLATTENING THE UPPER RIDGE OVER THE
AREA ON SATURDAY...AGAIN RESULTING FROM THE EJECTING IDAHO TROUGH.
EVENTUALLY...THE CLOSED UPPER LOW THAT FORMED OVER SASKATCHEWAN ON
SATURDAY WILL APPROACH THE AREA...PROGGED TO DROP INTO CENTRAL MN AT
12Z MONDAY AS A SHORTWAVE TROUGH. THIS TROUGH MAY EVEN BEGIN TO
PHASE WITH THE GENERAL TROUGHING OVER SOUTHEAST CANADA AS INDICATED
BY THE 00Z ECMWF.
WITH THE FLOW TURNING ZONAL ON SATURDAY...THE MAIN MOISTURE
TRANSPORT STREAM SUPPORTING CONVECTION TONIGHT SHOULD PUSH OFF TO
THE EAST. THUS...LIKE CLIMATOLOGY FOR NOCTURNAL CONVECTION...
EXPECTING IT TO WEAKEN THROUGH THE MORNING HOURS. HOWEVER...OUTFLOW
BOUNDARIES FROM THE CONVECTION AND WHAT SHOULD BE A COLD FRONT AT
THE SURFACE ARE SUGGESTED TO LAY UP OVER SOUTHERN SECTIONS OVER THE
FORECAST AREA. GROWING INSTABILITY FROM ANY DAYTIME HEATING PLUS A
HUMID AIRMASS CHARACTERIZED BY DEWPOINTS IN THE MID-UPPER
60S...ALONG WITH PRECIPITABLE WATER VALUES OF 1.5-1.8 INCHES...
SHOULD PROMOTE RENEWED CONVECTION. AGAIN...HEAVY RAIN WOULD BE THE
MAIN CONCERN AND THUS THE FLASH FLOOD WATCH GOES THROUGH THE DAY
SATURDAY. OUTFLOWS FROM THIS NEW CONVECTION COMBINED WITH THE COLD
FRONT DROPPING SOUTHEAST SHOULD PUSH MUCH OF THE CONVECTION OUT OF
THE AREA SOMETIME DURING THE EVENING. EXACT TIMING STILL HARD TO PIN
DOWN. LEFT SOME LOW CHANCES IN AFTER MIDNIGHT INTO THE DAY SUNDAY
ACROSS FAR SOUTHERN SECTIONS OF THE AREA WITH THE 14.00Z GFS/ECMWF
SHOWING SOME LIGHT QPF LINGERING. HOWEVER...BELIEVE THESE MIGHT BE
ABLE TO BE REMOVED IN LATER FORECASTS WITH A WEAK RIDGE OF HIGH
PRESSURE IN PLACE. ATTENTION SUNDAY NIGHT AND MONDAY TURNS TO THE
TROUGHING DROPPING INTO MINNESOTA. DPVA AHEAD OF THE TROUGH PLUS A
SURGE OF 850-700MB MOISTURE TRANSPORT MAY BE ENOUGH TO KICK OFF SOME
SHOWER AND THUNDERSTORM ACTIVITY. HOWEVER...THE TROUGH IS COMING
THROUGH AT THE WRONG TIME OF DAY TO GET EXCITED ABOUT IT...AND
MOISTURE IS LACKING WITH PRECIPITABLE WATER VALUES MAYBE AROUND 1
INCH. THEREFORE...HAVE ONLY WENT WITH 20-40 PERCENT CHANCES ACROSS
THE FORECAST AREA. 13.12Z/14.00Z ECMWF EVEN SUGGESTS THE TROUGH AND
ITS ASSOCIATED COLD FRONT COULD COME THROUGH THE AREA MAINLY DRY.
WITH WARMER 850MB TEMPS ON SATURDAY...14-17C...AND MORE SUNSHINE ON
SUNDAY WITH SIMILAR READINGS...EXPECT TEMPERATURES TO RISE EACH DAY.
MOST LOCATIONS SHOULD SEE GOOD MIXING ON SUNDAY...BOOSTING HIGHS
INTO THE LOW TO MID 80S. COOLER READINGS ON TAP FOR MONDAY WITH THE
COLD FRONT COMING THROUGH. GENERALLY FOLLOWED A BLEND OF GUIDANCE
FOR HIGHS AND LOWS.
MONDAY NIGHT THROUGH THURSDAY...
VERY GOOD MODEL AGREEMENT EXISTS AMONGST THE 14.00Z
ECMWF/GFS/CANADIAN AND GFS ENSEMBLES ON THE UPPER LEVEL PATTERN.
MUCH OF THE PERIOD IS DOMINATED BY TROUGHING ALONG THE U.S. WEST
COAST...RIDGING FROM THE NORTHWEST TERRITORIES OF CANADA INTO THE
CENTRAL PLAINS...AND TROUGHING OVER EASTERN CANADA INTO THE GREAT
LAKES. THIS MEANS MOSTLY A NORTHWEST FLOW OF COOL AND DRY AIR FROM
CANADA. THUS...MUCH OF THE FORECAST IS DRY. THERE ARE INDICATIONS OF
A SHORTWAVE DROPPING THROUGH THE WESTERN GREAT LAKES ON
THURSDAY...BRINGING A COLD FRONT INTO THE AREA. HAVE INCLUDED 20
PERCENT CHANCES FOR SHOWERS AND THUNDERSTORMS NORTH OF I-90 FOR THIS
FEATURE. TEMPERATURE WISE...THE COOLEST DAY LOOKS TO BE TUESDAY WITH
HIGH PRESSURE OVERHEAD AND 850MB TEMPS OF 8-10C. AIRMASS
MODIFICATION THANKS TO THE STRONG JUNE SUN SHOULD HELP WARM
TEMPERATURES EACH DAY THEREAFTER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 105 PM CDT FRI JUN 14 2013
SHORT WAVE ENERGY ALONG NORTHERN TIER OF STATES CONTINUES TO FIRE
THREAT FOR CONVECTION...EVEN WITH SHORT TERM RIDGE IN PLACE. TIMING
AND EXTENT OF THIS THREAT IS MAIN CHALLENGE FOR AVIATION WITH GOOD
VFR CONDITIONS IN PLACE RIGHT NOW.
EXPECT INITIAL DEVELOPMENT LATER TODAY TO THE WEST BUT UNCERTAINTY
IN WHERE AND EXACTLY WHEN. BANKING ON HIGHER CHANCES FOR STORMS TO
ROLL IN OVERNIGHT AND THEN PASS THROUGH TOWARDS DAYBREAK SATURDAY
WITH GENERAL RETURN TO VFR AFTER THAT. HARD TO GIVE EXACT TIMING OF
STORMS BUT WILL TRY AND NAIL DOWN 3-4 HOUR WINDOW WITH HIGHEST
CHANCES.
&&
.HYDROLOGY...LATE THIS AFTERNOON THROUGH SATURDAY
ISSUED AT 329 AM CDT FRI JUN 14 2013
VERY WET SOILS ACROSS MOWER AND FILLMORE COUNTIES IN MN ALONG WITH
MUCH OF NORTHEAST IOWA OVER THE PAST WEEK...AND REALLY THE PAST
COUPLE MONTHS...RESULT IN A HUGE CONCERN FOR FLOODING. THAT 1-2
INCHES OF RAINFALL THAT IMPACTED FLOYD COUNTY IA LATE WEDNESDAY...
MOSTLY IN A SHORT TIME PERIOD...CAUSED A LOT OF FLOODING ISSUES.
EXPECTING A BAND OF THUNDERSTORMS TO MOVE INTO MOWER THROUGH FLOYD
COUNTIES LATE THIS AFTERNOON...SLOWLY MOVING EAST THROUGH THE
EVENING. ADDITIONAL THUNDERSTORMS ARE FORECAST AFTER MIDNIGHT AND
THROUGH MUCH OF THE DAY SATURDAY SOUTH OF I-90. WITH PRECIPITABLE
WATER VALUES OF 1.5-1.8 INCHES AND WARM CLOUD DEPTHS OF 3500-4200
METERS ACCOMPANYING THESE THUNDERSTORMS...HEAVY RAIN IS LIKELY. WE
COULD BE LOOKING AT A WIDESPREAD 1-2 INCHES OF RAINFALL SOUTH OF
I-90...HIGHEST ACROSS NORTHEAST IOWA. LOCALLY HEAVIER RAINFALL IS
EASILY POSSIBLE.
GIVEN THE VERY WET SOILS AND POTENTIAL FOR HEAVY RAIN...HAVE ISSUED
A FLASH FLOOD WATCH FOR MOWER AND FILLMORE COUNTIES IN MN AND MUCH
OF NORTHEAST IA EXCEPT ALLAMAKEE. DEPENDING ON HOW CONVECTION
EVOLVES...THE WATCH MAY NEED TO BE EXPANDED EASTWARD...MOST LIKELY
INTO FAR SOUTHWEST WI.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...FLASH FLOOD WATCH FROM THIS AFTERNOON THROUGH SATURDAY EVENING
FOR MNZ094-095.
IA...FLASH FLOOD WATCH FROM THIS AFTERNOON THROUGH SATURDAY EVENING
FOR IAZ008>010-018-019-029-030.
&&
$$
SHORT TERM...AJ
LONG TERM....AJ
AVIATION.....SHEA
HYDROLOGY....AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
640 AM CDT FRI JUN 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 329 AM CDT FRI JUN 14 2013
MAIN FORECAST FOCUS IS ON POTENTIAL FOR HEAVY RAIN/FLASH FLOODING
LATER TODAY THROUGH SATURDAY.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A HIGHLY AMPLIFIED PATTERN ACROSS NORTH AMERICA...CONSISTING
OF TROUGHING OVER ALBERTA AND IDAHO...RIDGING FROM THE SOUTHERN
PLAINS INTO MANITOBA...AND TROUGHING FROM SOUTHEAST CANADA SOUTHWARD
ALONG THE EAST COAST OF THE U.S.. THE FORECAST AREA LIES ON THE
SUBSIDENT SIDE OF THE RIDGING...RESULTING IN HIGH PRESSURE AT THE
SURFACE WHICH EXISTS OVER WISCONSIN. 00Z SOUNDINGS FROM MPX...GRB
AND DVN DEPICTED A DRY AIRMASS WITH THIS HIGH PRESSURE AREA WITH
PRECIPITABLE WATER VALUES OF 0.7-0.8 INCHES OR 80-90 PERCENT OF
NORMAL. THE DRY AIRMASS HAS HELPED KEEP SKIES MOSTLY CLEAR OVERNIGHT
AND WITH LIGHT WINDS...TEMPERATURES HAVE DROPPED INTO THE UPPER 40S
TO UPPER 50S. MEANWHILE...TO THE WEST UNDER AND WEST OF THE UPPER
RIDGE AXIS...MOISTURE HAS BEEN GRADUALLY ADVECTING NORTHWARD THROUGH
THE PLAINS ON A 30-45 KT 850MB JET PER VWP DATA. GOES DERIVED
PRECIPITABLE WATER SHOWED VALUES OF 1-1.5 INCHES ACROSS MUCH OF THE
PLAINS...HIGHEST ACROSS SOUTH CENTRAL NEBRASKA AND NORTH CENTRAL KS.
THIS MAXIMA WAS ALSO CORRELATED WITH THE REMNANTS OF AN MCS THAT
INITIATED OFF THE FRONT RANGE IN COLORADO YESTERDAY AFTERNOON. ALONG
WITH THE INCREASED MOISTURE...00Z RAOBS SHOWED 850MB TEMPS OF 16-21C
FROM RAPID CITY TO OMAHA AND TOPEKA...QUITE A BIT WARMER COMPARED TO
THE 10-13C AROUND THE FORECAST AREA. ALONG THE GRADIENT OF THIS
TEMPERATURE DIFFERENCE...A NARROW LINE OF SHOWERS AND THUNDERSTORMS
HAS BROKE OUT OVER SOUTHWEST MN INTO WESTERN IA.
OVER THE NEXT 24 HOURS...THE UPPER RIDGE AXIS OVER THE PLAINS IS
PROGGED TO SHIFT EAST OVER THE FORECAST AREA. THIS IS IN RESPONSE TO
THE TROUGH OVER IDAHO AND ALBERTA EJECTING NORTHEAST...AS WELL AS
FORMING A DEEP CLOSED LOW CIRCULATION OVER CENTRAL SASKATCHEWAN.
WHAT THIS MEANS FOR THE FORECAST AREA IS ALL OF THAT WARMER 850MB
AIR AND HIGHER PRECIPITABLE WATER UNDER THE UPPER RIDGE WILL MOVE
TOWARDS US. GIVEN THE WARM ADVECTION PATTERN...EXPECT CONCERN FOR
PRECIPITATION TO INCREASE. IN ADDITION...CONVECTIVELY INDUCED
SHORTWAVES FROM CONVECTION COMING OFF THE ROCKIES AND THE PLAINS
THIS MORNING...AND THOSE THAT FIRE THIS AFTERNOON...WILL ALSO PLAY A
ROLE AS THEY HEAD NORTHEAST AROUND THE UPPER RIDGE.
FOR TODAY...GENERAL CONSENSUS FROM THE MODELS IS FOR INCREASING
310-315K ISENTROPIC LIFT AND 700MB MOISTURE TRANSPORT TO COME ACROSS
THE FORECAST AREA DURING THE AFTERNOON. ANTICIPATING AN
ALTOSTRATUS/ACCAS DECK TO FORM AS A RESULT AND OVERSPREAD MUCH OF
THE AREA. THIS CAN ALREADY BE SEEN ALONG THE DAKOTAS/MN BORDER WHERE
THOSE SHOWERS AND THUNDERSTORMS HAVE BEEN OCCURRING. HAVE
CONTINUED THE MENTION OF SOME LOW PROBABILITIES FOR PRECIPITATION
WEST OF THE MS RIVER EARLY THIS AFTERNOON TO ACCOUNT FOR THIS SHOWER
POTENTIAL.
LATE IN THE AFTERNOON...SOMETHING TO WATCH IS THE 14.00Z NAM
SCENARIO WHICH DEPICTS A LARGER AMOUNT OF CONVECTION OVER SOUTH
CENTRAL MN AND NORTH CENTRAL IA...CLIPPING FAR WESTERN PORTIONS OF
THE FORECAST AREA. THE GFS/ECMWF/REGIONAL CANADIAN ARE VERY
SIMILAR...THOUGH QPF VALUES ARE NOT NEARLY AS HIGH WHICH MAY BE A
RESULT OF MODEL RESOLUTION. THE SITUATION APPEARS TO BE A RESULT OF
INCREASING 700-850MB MOISTURE TRANSPORT...ON THE LEADING EDGE OF THE
HIGHER PRECIPITABLE WATER VALUES OF 1.5-1.8 INCHES PER RAP COMING
INTO WESTERN IA...CAPE OF 1000 J/KG OR SO THAT IS UNCAPPED LIFTED
FROM 725MB...AND A POSSIBLE RIGHT ENTRANCE REGION OF A JET STREAK
TRACKING SOUTHEAST THROUGH WISCONSIN. SHOULD THIS PAN OUT...GIVEN
THE HIGH PRECIPITABLE WATER...THESE STORMS WILL BE HEAVY RAIN
PRODUCERS.
NAM/GFS/ECMWF/REGIONAL CANADIAN MOISTURE TRANSPORT FIELDS FROM
925-700MB ARE ALL IN AGREEMENT THAT THE STREAM SHIFTS NORTHEAST
TONIGHT...FOLLOWING THE UPPER RIDGE AXIS. THUS...THINKING THE
CONVECTION THAT FIRES LATE THIS AFTERNOON SHOULD SLOWLY PROGRESS
EASTWARD THROUGH THE FORECAST AREA. ADDITIONALLY...IT APPEARS THERE
IS A SECOND SURGE OF MOISTURE TRANSPORT COMING UP OUT OF KS INTO
CENTRAL IA OVERNIGHT...LIKELY FIRING MORE CONVECTION ON ITS NOSE
FROM NORTH CENTRAL INTO EASTERN IA. THE ECMWF HAS BEEN EXTREMELY
CONSISTENT RUN TO RUN WITH THIS.
ALTHOUGH INSTABILITY IS ADVECTING TOWARDS US ON THIS MOISTURE
TRANSPORT...THE INSTABILITY IS TALL AND SKINNY. WITH WARM CLOUD
DEPTHS APPROACHING 14 KFT...THINKING HEAVY RAIN WOULD BE THE MAIN
SEVERE WEATHER CONCERN. ADDITIONALLY...THE 2-7KM SHEAR WHICH IS MORE
REPRESENTATIVE OF THE INSTABILITY USED BY THE STORMS...IS LESS THAN
30 KTS. SEE THE HYDROLOGY SECTION BELOW FOR MORE ON THE IMPACTS FROM
THE PRECIPITATION. MAIN THING TO NOTE HERE IS THAT GIVEN THE MOIST
SOILS OVER PORTIONS OF NORTHEAST IA AND SOUTHEAST MN...ANY HEAVY
RAIN MAY CAUSE FLASH FLOODING...ESPECIALLY IN FLOYD AND MITCHELL
COUNTIES IN IA. THEREFORE...HAVE ISSUED FLASH FLOOD WATCHES FOR THE
MOST CONCERNING AREAS.
850MB TEMPERATURES ARE PROGGED TO STAY BETWEEN 10-13C TODAY. WITH
INCREASING CLOUDS...TEMPERATURES SHOULD END UP NEAR OR A LITTLE
BELOW YESTERDAY HIGHS. WARMER NIGHT ON TAP AS HIGHER DEWPOINTS MOVE
IN ACCOMPANYING THE HIGHER PRECIPITABLE WATER.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 329 AM CDT FRI JUN 14 2013
SATURDAY THROUGH MONDAY...
MODELS ARE IN GOOD AGREEMENT FLATTENING THE UPPER RIDGE OVER THE
AREA ON SATURDAY...AGAIN RESULTING FROM THE EJECTING IDAHO TROUGH.
EVENTUALLY...THE CLOSED UPPER LOW THAT FORMED OVER SASKATCHEWAN ON
SATURDAY WILL APPROACH THE AREA...PROGGED TO DROP INTO CENTRAL MN AT
12Z MONDAY AS A SHORTWAVE TROUGH. THIS TROUGH MAY EVEN BEGIN TO
PHASE WITH THE GENERAL TROUGHING OVER SOUTHEAST CANADA AS INDICATED
BY THE 00Z ECMWF.
WITH THE FLOW TURNING ZONAL ON SATURDAY...THE MAIN MOISTURE
TRANSPORT STREAM SUPPORTING CONVECTION TONIGHT SHOULD PUSH OFF TO
THE EAST. THUS...LIKE CLIMATOLOGY FOR NOCTURNAL CONVECTION...
EXPECTING IT TO WEAKEN THROUGH THE MORNING HOURS. HOWEVER...OUTFLOW
BOUNDARIES FROM THE CONVECTION AND WHAT SHOULD BE A COLD FRONT AT
THE SURFACE ARE SUGGESTED TO LAY UP OVER SOUTHERN SECTIONS OVER THE
FORECAST AREA. GROWING INSTABILITY FROM ANY DAYTIME HEATING PLUS A
HUMID AIRMASS CHARACTERIZED BY DEWPOINTS IN THE MID-UPPER
60S...ALONG WITH PRECIPITABLE WATER VALUES OF 1.5-1.8 INCHES...
SHOULD PROMOTE RENEWED CONVECTION. AGAIN...HEAVY RAIN WOULD BE THE
MAIN CONCERN AND THUS THE FLASH FLOOD WATCH GOES THROUGH THE DAY
SATURDAY. OUTFLOWS FROM THIS NEW CONVECTION COMBINED WITH THE COLD
FRONT DROPPING SOUTHEAST SHOULD PUSH MUCH OF THE CONVECTION OUT OF
THE AREA SOMETIME DURING THE EVENING. EXACT TIMING STILL HARD TO PIN
DOWN. LEFT SOME LOW CHANCES IN AFTER MIDNIGHT INTO THE DAY SUNDAY
ACROSS FAR SOUTHERN SECTIONS OF THE AREA WITH THE 14.00Z GFS/ECMWF
SHOWING SOME LIGHT QPF LINGERING. HOWEVER...BELIEVE THESE MIGHT BE
ABLE TO BE REMOVED IN LATER FORECASTS WITH A WEAK RIDGE OF HIGH
PRESSURE IN PLACE. ATTENTION SUNDAY NIGHT AND MONDAY TURNS TO THE
TROUGHING DROPPING INTO MINNESOTA. DPVA AHEAD OF THE TROUGH PLUS A
SURGE OF 850-700MB MOISTURE TRANSPORT MAY BE ENOUGH TO KICK OFF SOME
SHOWER AND THUNDERSTORM ACTIVITY. HOWEVER...THE TROUGH IS COMING
THROUGH AT THE WRONG TIME OF DAY TO GET EXCITED ABOUT IT...AND
MOISTURE IS LACKING WITH PRECIPITABLE WATER VALUES MAYBE AROUND 1
INCH. THEREFORE...HAVE ONLY WENT WITH 20-40 PERCENT CHANCES ACROSS
THE FORECAST AREA. 13.12Z/14.00Z ECMWF EVEN SUGGESTS THE TROUGH AND
ITS ASSOCIATED COLD FRONT COULD COME THROUGH THE AREA MAINLY DRY.
WITH WARMER 850MB TEMPS ON SATURDAY...14-17C...AND MORE SUNSHINE ON
SUNDAY WITH SIMILAR READINGS...EXPECT TEMPERATURES TO RISE EACH DAY.
MOST LOCATIONS SHOULD SEE GOOD MIXING ON SUNDAY...BOOSTING HIGHS
INTO THE LOW TO MID 80S. COOLER READINGS ON TAP FOR MONDAY WITH THE
COLD FRONT COMING THROUGH. GENERALLY FOLLOWED A BLEND OF GUIDANCE
FOR HIGHS AND LOWS.
MONDAY NIGHT THROUGH THURSDAY...
VERY GOOD MODEL AGREEMENT EXISTS AMONGST THE 14.00Z
ECMWF/GFS/CANADIAN AND GFS ENSEMBLES ON THE UPPER LEVEL PATTERN.
MUCH OF THE PERIOD IS DOMINATED BY TROUGHING ALONG THE U.S. WEST
COAST...RIDGING FROM THE NORTHWEST TERRITORIES OF CANADA INTO THE
CENTRAL PLAINS...AND TROUGHING OVER EASTERN CANADA INTO THE GREAT
LAKES. THIS MEANS MOSTLY A NORTHWEST FLOW OF COOL AND DRY AIR FROM
CANADA. THUS...MUCH OF THE FORECAST IS DRY. THERE ARE INDICATIONS OF
A SHORTWAVE DROPPING THROUGH THE WESTERN GREAT LAKES ON
THURSDAY...BRINGING A COLD FRONT INTO THE AREA. HAVE INCLUDED 20
PERCENT CHANCES FOR SHOWERS AND THUNDERSTORMS NORTH OF I-90 FOR THIS
FEATURE. TEMPERATURE WISE...THE COOLEST DAY LOOKS TO BE TUESDAY WITH
HIGH PRESSURE OVERHEAD AND 850MB TEMPS OF 8-10C. AIRMASS
MODIFICATION THANKS TO THE STRONG JUNE SUN SHOULD HELP WARM
TEMPERATURES EACH DAY THEREAFTER.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 640 AM CDT THU JUN 13 2013
HIGH PRESSURE WILL CONTINUE TO MOVE EAST OF THE AREA TODAY...WITH
LOW PRESSURE AND A COLD FRONT MOVING INTO MN/IA TONIGHT. VFR
CONDITIONS THIS MORNING WILL GIVE WAY TO GRADUALLY LOWERING
CONDITIONS THIS AFTERNOON AND TONIGHT AS THE LOW/FRONT MOVE INTO THE
REGION. WITH A WIDE VARIETY OF CONVECTION OUTCOMES AMONG THE
FORECAST MODELS...NOT A LOT OF CONFIDENCE ON THE DETAILS OF SHRA/
TSRA EXPECTED TO SPREAD WEST TO EAST ACROSS THE AREA LATER THIS
AFTERNOON THRU TONIGHT.
RATHER THAN BURY THE KRST/KLSE TAFS IN LONG PERIODS OF TSRA OR IFR
CONDITIONS WHEN CONFIDENCE IS LOWER THAN AVERAGE...JUST CARRIED A
TREND CIGS/VSBYS GRADUALLY LOWERING INTO MVFR TONIGHT. CONTINUED A
PERIOD OF TSRA THIS EVENING WHEN THERE IS SOME MODEL CONSISTENCY FOR
STRONGER FORCING/INCREASED MOISTURE AND INSTABILITY TO BE OVER THE
AREA. SHRA/EMBEDDED TSRA LOOKING TO PERSIST OVERNIGHT BUT WITH THE
LOWER CONFIDENCE LEFT TSRA MENTION OUT OF THE OVERNIGHT HOURS FOR
NOW.
&&
.HYDROLOGY...LATE THIS AFTERNOON THROUGH SATURDAY
ISSUED AT 329 AM CDT FRI JUN 14 2013
VERY WET SOILS ACROSS MOWER AND FILLMORE COUNTIES IN MN ALONG WITH
MUCH OF NORTHEAST IOWA OVER THE PAST WEEK...AND REALLY THE PAST
COUPLE MONTHS...RESULT IN A HUGE CONCERN FOR FLOODING. THAT 1-2
INCHES OF RAINFALL THAT IMPACTED FLOYD COUNTY IA LATE WEDNESDAY...
MOSTLY IN A SHORT TIME PERIOD...CAUSED A LOT OF FLOODING ISSUES.
EXPECTING A BAND OF THUNDERSTORMS TO MOVE INTO MOWER THROUGH FLOYD
COUNTIES LATE THIS AFTERNOON...SLOWLY MOVING EAST THROUGH THE
EVENING. ADDITIONAL THUNDERSTORMS ARE FORECAST AFTER MIDNIGHT AND
THROUGH MUCH OF THE DAY SATURDAY SOUTH OF I-90. WITH PRECIPITABLE
WATER VALUES OF 1.5-1.8 INCHES AND WARM CLOUD DEPTHS OF 3500-4200
METERS ACCOMPANYING THESE THUNDERSTORMS...HEAVY RAIN IS LIKELY. WE
COULD BE LOOKING AT A WIDESPREAD 1-2 INCHES OF RAINFALL SOUTH OF
I-90...HIGHEST ACROSS NORTHEAST IOWA. LOCALLY HEAVIER RAINFALL IS
EASILY POSSIBLE.
GIVEN THE VERY WET SOILS AND POTENTIAL FOR HEAVY RAIN...HAVE ISSUED
A FLASH FLOOD WATCH FOR MOWER AND FILLMORE COUNTIES IN MN AND MUCH
OF NORTHEAST IA EXCEPT ALLAMAKEE. DEPENDING ON HOW CONVECTION
EVOLVES...THE WATCH MAY NEED TO BE EXPANDED EASTWARD...MOST LIKELY
INTO FAR SOUTHWEST WI.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...FLASH FLOOD WATCH FROM THIS AFTERNOON THROUGH SATURDAY EVENING
FOR MNZ094-095.
IA...FLASH FLOOD WATCH FROM THIS AFTERNOON THROUGH SATURDAY EVENING
FOR IAZ008>010-018-019-029-030.
&&
$$
SHORT TERM...AJ
LONG TERM....AJ
AVIATION.....RRS
HYDROLOGY....AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
329 AM CDT FRI JUN 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 329 AM CDT FRI JUN 14 2013
MAIN FORECAST FOCUS IS ON POTENTIAL FOR HEAVY RAIN/FLASH FLOODING
LATER TODAY THROUGH SATURDAY.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A HIGHLY AMPLIFIED PATTERN ACROSS NORTH AMERICA...CONSISTING
OF TROUGHING OVER ALBERTA AND IDAHO...RIDGING FROM THE SOUTHERN
PLAINS INTO MANITOBA...AND TROUGHING FROM SOUTHEAST CANADA SOUTHWARD
ALONG THE EAST COAST OF THE U.S.. THE FORECAST AREA LIES ON THE
SUBSIDENT SIDE OF THE RIDGING...RESULTING IN HIGH PRESSURE AT THE
SURFACE WHICH EXISTS OVER WISCONSIN. 00Z SOUNDINGS FROM MPX...GRB
AND DVN DEPICTED A DRY AIRMASS WITH THIS HIGH PRESSURE AREA WITH
PRECIPITABLE WATER VALUES OF 0.7-0.8 INCHES OR 80-90 PERCENT OF
NORMAL. THE DRY AIRMASS HAS HELPED KEEP SKIES MOSTLY CLEAR OVERNIGHT
AND WITH LIGHT WINDS...TEMPERATURES HAVE DROPPED INTO THE UPPER 40S
TO UPPER 50S. MEANWHILE...TO THE WEST UNDER AND WEST OF THE UPPER
RIDGE AXIS...MOISTURE HAS BEEN GRADUALLY ADVECTING NORTHWARD THROUGH
THE PLAINS ON A 30-45 KT 850MB JET PER VWP DATA. GOES DERIVED
PRECIPITABLE WATER SHOWED VALUES OF 1-1.5 INCHES ACROSS MUCH OF THE
PLAINS...HIGHEST ACROSS SOUTH CENTRAL NEBRASKA AND NORTH CENTRAL KS.
THIS MAXIMA WAS ALSO CORRELATED WITH THE REMNANTS OF AN MCS THAT
INITIATED OFF THE FRONT RANGE IN COLORADO YESTERDAY AFTERNOON. ALONG
WITH THE INCREASED MOISTURE...00Z RAOBS SHOWED 850MB TEMPS OF 16-21C
FROM RAPID CITY TO OMAHA AND TOPEKA...QUITE A BIT WARMER COMPARED TO
THE 10-13C AROUND THE FORECAST AREA. ALONG THE GRADIENT OF THIS
TEMPERATURE DIFFERENCE...A NARROW LINE OF SHOWERS AND THUNDERSTORMS
HAS BROKE OUT OVER SOUTHWEST MN INTO WESTERN IA.
OVER THE NEXT 24 HOURS...THE UPPER RIDGE AXIS OVER THE PLAINS IS
PROGGED TO SHIFT EAST OVER THE FORECAST AREA. THIS IS IN RESPONSE TO
THE TROUGH OVER IDAHO AND ALBERTA EJECTING NORTHEAST...AS WELL AS
FORMING A DEEP CLOSED LOW CIRCULATION OVER CENTRAL SASKATCHEWAN.
WHAT THIS MEANS FOR THE FORECAST AREA IS ALL OF THAT WARMER 850MB
AIR AND HIGHER PRECIPITABLE WATER UNDER THE UPPER RIDGE WILL MOVE
TOWARDS US. GIVEN THE WARM ADVECTION PATTERN...EXPECT CONCERN FOR
PRECIPITATION TO INCREASE. IN ADDITION...CONVECTIVELY INDUCED
SHORTWAVES FROM CONVECTION COMING OFF THE ROCKIES AND THE PLAINS
THIS MORNING...AND THOSE THAT FIRE THIS AFTERNOON...WILL ALSO PLAY A
ROLE AS THEY HEAD NORTHEAST AROUND THE UPPER RIDGE.
FOR TODAY...GENERAL CONSENSUS FROM THE MODELS IS FOR INCREASING
310-315K ISENTROPIC LIFT AND 700MB MOISTURE TRANSPORT TO COME ACROSS
THE FORECAST AREA DURING THE AFTERNOON. ANTICIPATING AN
ALTOSTRATUS/ACCAS DECK TO FORM AS A RESULT AND OVERSPREAD MUCH OF
THE AREA. THIS CAN ALREADY BE SEEN ALONG THE DAKOTAS/MN BORDER WHERE
THOSE SHOWERS AND THUNDERSTORMS HAVE BEEN OCCURRING. HAVE
CONTINUED THE MENTION OF SOME LOW PROBABILITIES FOR PRECIPITATION
WEST OF THE MS RIVER EARLY THIS AFTERNOON TO ACCOUNT FOR THIS SHOWER
POTENTIAL.
LATE IN THE AFTERNOON...SOMETHING TO WATCH IS THE 14.00Z NAM
SCENARIO WHICH DEPICTS A LARGER AMOUNT OF CONVECTION OVER SOUTH
CENTRAL MN AND NORTH CENTRAL IA...CLIPPING FAR WESTERN PORTIONS OF
THE FORECAST AREA. THE GFS/ECMWF/REGIONAL CANADIAN ARE VERY
SIMILAR...THOUGH QPF VALUES ARE NOT NEARLY AS HIGH WHICH MAY BE A
RESULT OF MODEL RESOLUTION. THE SITUATION APPEARS TO BE A RESULT OF
INCREASING 700-850MB MOISTURE TRANSPORT...ON THE LEADING EDGE OF THE
HIGHER PRECIPITABLE WATER VALUES OF 1.5-1.8 INCHES PER RAP COMING
INTO WESTERN IA...CAPE OF 1000 J/KG OR SO THAT IS UNCAPPED LIFTED
FROM 725MB...AND A POSSIBLE RIGHT ENTRANCE REGION OF A JET STREAK
TRACKING SOUTHEAST THROUGH WISCONSIN. SHOULD THIS PAN OUT...GIVEN
THE HIGH PRECIPITABLE WATER...THESE STORMS WILL BE HEAVY RAIN
PRODUCERS.
NAM/GFS/ECMWF/REGIONAL CANADIAN MOISTURE TRANSPORT FIELDS FROM
925-700MB ARE ALL IN AGREEMENT THAT THE STREAM SHIFTS NORTHEAST
TONIGHT...FOLLOWING THE UPPER RIDGE AXIS. THUS...THINKING THE
CONVECTION THAT FIRES LATE THIS AFTERNOON SHOULD SLOWLY PROGRESS
EASTWARD THROUGH THE FORECAST AREA. ADDITIONALLY...IT APPEARS THERE
IS A SECOND SURGE OF MOISTURE TRANSPORT COMING UP OUT OF KS INTO
CENTRAL IA OVERNIGHT...LIKELY FIRING MORE CONVECTION ON ITS NOSE
FROM NORTH CENTRAL INTO EASTERN IA. THE ECMWF HAS BEEN EXTREMELY
CONSISTENT RUN TO RUN WITH THIS.
ALTHOUGH INSTABILITY IS ADVECTING TOWARDS US ON THIS MOISTURE
TRANSPORT...THE INSTABILITY IS TALL AND SKINNY. WITH WARM CLOUD
DEPTHS APPROACHING 14 KFT...THINKING HEAVY RAIN WOULD BE THE MAIN
SEVERE WEATHER CONCERN. ADDITIONALLY...THE 2-7KM SHEAR WHICH IS MORE
REPRESENTATIVE OF THE INSTABILITY USED BY THE STORMS...IS LESS THAN
30 KTS. SEE THE HYDROLOGY SECTION BELOW FOR MORE ON THE IMPACTS FROM
THE PRECIPITATION. MAIN THING TO NOTE HERE IS THAT GIVEN THE MOIST
SOILS OVER PORTIONS OF NORTHEAST IA AND SOUTHEAST MN...ANY HEAVY
RAIN MAY CAUSE FLASH FLOODING...ESPECIALLY IN FLOYD AND MITCHELL
COUNTIES IN IA. THEREFORE...HAVE ISSUED FLASH FLOOD WATCHES FOR THE
MOST CONCERNING AREAS.
850MB TEMPERATURES ARE PROGGED TO STAY BETWEEN 10-13C TODAY. WITH
INCREASING CLOUDS...TEMPERATURES SHOULD END UP NEAR OR A LITTLE
BELOW YESTERDAY HIGHS. WARMER NIGHT ON TAP AS HIGHER DEWPOINTS MOVE
IN ACCOMPANYING THE HIGHER PRECIPITABLE WATER.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 329 AM CDT FRI JUN 14 2013
SATURDAY THROUGH MONDAY...
MODELS ARE IN GOOD AGREEMENT FLATTENING THE UPPER RIDGE OVER THE
AREA ON SATURDAY...AGAIN RESULTING FROM THE EJECTING IDAHO TROUGH.
EVENTUALLY...THE CLOSED UPPER LOW THAT FORMED OVER SASKATCHEWAN ON
SATURDAY WILL APPROACH THE AREA...PROGGED TO DROP INTO CENTRAL MN AT
12Z MONDAY AS A SHORTWAVE TROUGH. THIS TROUGH MAY EVEN BEGIN TO
PHASE WITH THE GENERAL TROUGHING OVER SOUTHEAST CANADA AS INDICATED
BY THE 00Z ECMWF.
WITH THE FLOW TURNING ZONAL ON SATURDAY...THE MAIN MOISTURE
TRANSPORT STREAM SUPPORTING CONVECTION TONIGHT SHOULD PUSH OFF TO
THE EAST. THUS...LIKE CLIMATOLOGY FOR NOCTURNAL CONVECTION...
EXPECTING IT TO WEAKEN THROUGH THE MORNING HOURS. HOWEVER...OUTFLOW
BOUNDARIES FROM THE CONVECTION AND WHAT SHOULD BE A COLD FRONT AT
THE SURFACE ARE SUGGESTED TO LAY UP OVER SOUTHERN SECTIONS OVER THE
FORECAST AREA. GROWING INSTABILITY FROM ANY DAYTIME HEATING PLUS A
HUMID AIRMASS CHARACTERIZED BY DEWPOINTS IN THE MID-UPPER
60S...ALONG WITH PRECIPITABLE WATER VALUES OF 1.5-1.8 INCHES...
SHOULD PROMOTE RENEWED CONVECTION. AGAIN...HEAVY RAIN WOULD BE THE
MAIN CONCERN AND THUS THE FLASH FLOOD WATCH GOES THROUGH THE DAY
SATURDAY. OUTFLOWS FROM THIS NEW CONVECTION COMBINED WITH THE COLD
FRONT DROPPING SOUTHEAST SHOULD PUSH MUCH OF THE CONVECTION OUT OF
THE AREA SOMETIME DURING THE EVENING. EXACT TIMING STILL HARD TO PIN
DOWN. LEFT SOME LOW CHANCES IN AFTER MIDNIGHT INTO THE DAY SUNDAY
ACROSS FAR SOUTHERN SECTIONS OF THE AREA WITH THE 14.00Z GFS/ECMWF
SHOWING SOME LIGHT QPF LINGERING. HOWEVER...BELIEVE THESE MIGHT BE
ABLE TO BE REMOVED IN LATER FORECASTS WITH A WEAK RIDGE OF HIGH
PRESSURE IN PLACE. ATTENTION SUNDAY NIGHT AND MONDAY TURNS TO THE
TROUGHING DROPPING INTO MINNESOTA. DPVA AHEAD OF THE TROUGH PLUS A
SURGE OF 850-700MB MOISTURE TRANSPORT MAY BE ENOUGH TO KICK OFF SOME
SHOWER AND THUNDERSTORM ACTIVITY. HOWEVER...THE TROUGH IS COMING
THROUGH AT THE WRONG TIME OF DAY TO GET EXCITED ABOUT IT...AND
MOISTURE IS LACKING WITH PRECIPITABLE WATER VALUES MAYBE AROUND 1
INCH. THEREFORE...HAVE ONLY WENT WITH 20-40 PERCENT CHANCES ACROSS
THE FORECAST AREA. 13.12Z/14.00Z ECMWF EVEN SUGGESTS THE TROUGH AND
ITS ASSOCIATED COLD FRONT COULD COME THROUGH THE AREA MAINLY DRY.
WITH WARMER 850MB TEMPS ON SATURDAY...14-17C...AND MORE SUNSHINE ON
SUNDAY WITH SIMILAR READINGS...EXPECT TEMPERATURES TO RISE EACH DAY.
MOST LOCATIONS SHOULD SEE GOOD MIXING ON SUNDAY...BOOSTING HIGHS
INTO THE LOW TO MID 80S. COOLER READINGS ON TAP FOR MONDAY WITH THE
COLD FRONT COMING THROUGH. GENERALLY FOLLOWED A BLEND OF GUIDANCE
FOR HIGHS AND LOWS.
MONDAY NIGHT THROUGH THURSDAY...
VERY GOOD MODEL AGREEMENT EXISTS AMONGST THE 14.00Z
ECMWF/GFS/CANADIAN AND GFS ENSEMBLES ON THE UPPER LEVEL PATTERN.
MUCH OF THE PERIOD IS DOMINATED BY TROUGHING ALONG THE U.S. WEST
COAST...RIDGING FROM THE NORTHWEST TERRITORIES OF CANADA INTO THE
CENTRAL PLAINS...AND TROUGHING OVER EASTERN CANADA INTO THE GREAT
LAKES. THIS MEANS MOSTLY A NORTHWEST FLOW OF COOL AND DRY AIR FROM
CANADA. THUS...MUCH OF THE FORECAST IS DRY. THERE ARE INDICATIONS OF
A SHORTWAVE DROPPING THROUGH THE WESTERN GREAT LAKES ON
THURSDAY...BRINGING A COLD FRONT INTO THE AREA. HAVE INCLUDED 20
PERCENT CHANCES FOR SHOWERS AND THUNDERSTORMS NORTH OF I-90 FOR THIS
FEATURE. TEMPERATURE WISE...THE COOLEST DAY LOOKS TO BE TUESDAY WITH
HIGH PRESSURE OVERHEAD AND 850MB TEMPS OF 8-10C. AIRMASS
MODIFICATION THANKS TO THE STRONG JUNE SUN SHOULD HELP WARM
TEMPERATURES EACH DAY THEREAFTER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY EVENING)
ISSUED AT 1145 PM CDT THU JUN 13 2013
HIGH PRESSURE BUILDS ACROSS THE REGION TONIGHT...WITH SKC SKIES AND
VRB TO LIGHT EAST WINDS. HIGH CLOUDS WILL BE ON THE INCREASE FRI
AFTERNOON...AHEAD OF AN ANTICIPATED AREA OF SHRA/TS MOVING NORTHEAST
AHEAD OF A WARM FRONT. PCPN IS LIKELY FOR KRST/KLSE FRIDAY NIGHT
INTO SATURDAY...WITH A LOWERING IN CIG HEIGHTS AS THE SHRA/TS MOVE
IN. PERIODS OF MVFR APPEARS LIKELY AT THIS TIME...WITH SOME
RESTRICTIONS IN VSBY. PARAMETERS SUGGEST THAT THE SHOWERS AND STORMS
COULD BE EFFICIENT RAIN PRODUCERS...AND HEAVY RAIN WILL BE POSSIBLE.
WINDS WILL INCREASE AND TURN FROM EAST TO SOUTHEAST ON FRIDAY.
SOME MESO MODELS ARE SUGGESTING THE POTENTIAL FOR SCT/ISOLD
SHRA/TS AHEAD OF THE EXPECTED PCPN FOR FRIDAY NIGHT...DEVELOPING IN
THE MID LEVEL WARM AIR ADVECTIVE WING OF THE APPROACHING SYSTEM. AT
THIS TIME...ANYTHING THAT WOULD DEVELOP WOULD COME OUT OF A MID /10
KFT/ LEVEL CLOUD DECK...WITH MINIMAL/IF ANY ACCUMULATIONS. ACTIVITY
IS NOT A FOR SURE THING...AND LOOKS LIMITED IN AREAL EXTENT...SO
WILL LEAVE OUT OF THE TAFS FOR NOW.
&&
.HYDROLOGY...LATE THIS AFTERNOON THROUGH SATURDAY
ISSUED AT 329 AM CDT FRI JUN 14 2013
VERY WET SOILS ACROSS MOWER AND FILLMORE COUNTIES IN MN ALONG WITH
MUCH OF NORTHEAST IOWA OVER THE PAST WEEK...AND REALLY THE PAST
COUPLE MONTHS...RESULT IN A HUGE CONCERN FOR FLOODING. THAT 1-2
INCHES OF RAINFALL THAT IMPACTED FLOYD COUNTY IA LATE WEDNESDAY...
MOSTLY IN A SHORT TIME PERIOD...CAUSED A LOT OF FLOODING ISSUES.
EXPECTING A BAND OF THUNDERSTORMS TO MOVE INTO MOWER THROUGH FLOYD
COUNTIES LATE THIS AFTERNOON...SLOWLY MOVING EAST THROUGH THE
EVENING. ADDITIONAL THUNDERSTORMS ARE FORECAST AFTER MIDNIGHT AND
THROUGH MUCH OF THE DAY SATURDAY SOUTH OF I-90. WITH PRECIPITABLE
WATER VALUES OF 1.5-1.8 INCHES AND WARM CLOUD DEPTHS OF 3500-4200
METERS ACCOMPANYING THESE THUNDERSTORMS...HEAVY RAIN IS LIKELY. WE
COULD BE LOOKING AT A WIDESPREAD 1-2 INCHES OF RAINFALL SOUTH OF
I-90...HIGHEST ACROSS NORTHEAST IOWA. LOCALLY HEAVIER RAINFALL IS
EASILY POSSIBLE.
GIVEN THE VERY WET SOILS AND POTENTIAL FOR HEAVY RAIN...HAVE ISSUED
A FLASH FLOOD WATCH FOR MOWER AND FILLMORE COUNTIES IN MN AND MUCH
OF NORTHEAST IA EXCEPT ALLAMAKEE. DEPENDING ON HOW CONVECTION
EVOLVES...THE WATCH MAY NEED TO BE EXPANDED EASTWARD...MOST LIKELY
INTO FAR SOUTHWEST WI.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...FLASH FLOOD WATCH FROM THIS AFTERNOON THROUGH SATURDAY EVENING
FOR MNZ094-095.
IA...FLASH FLOOD WATCH FROM THIS AFTERNOON THROUGH SATURDAY EVENING
FOR IAZ008>010-018-019-029-030.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION......RIECK
HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
200 AM EDT SUN JUN 16 2013
.SYNOPSIS...
HIGH PRESSURE RIDGING INTO THE FORECAST AREAS FROM THE ATLANTIC
OCEAN WILL WEAKEN. MOISTURE WILL INCREASE IN THE SOUTH FLOW
ASSOCIATED WITH THE OFFSHORE HIGH AS A FRONT SLOWLY APPROACHES
FROM THE NORTH.
&&
.NEAR TERM /THROUGH TODAY/...
HIGH PRESSURE RIDGING INTO THE FORECAST AREA FROM THE ATLANTIC
WILL DOMINATE TODAY. MOISTURE WILL REMAIN SHALLOW AND A MID-LEVEL
SHORTWAVE RIDGE WILL HELP MAINTAIN THE CAPPING. ALL OF THE MOS
INDICATES POPS LESS THAN 10 PERCENT. USED THE GUIDANCE CONSENSUS
FOR THE TEMPERATURE FORECAST.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
MOISTURE WILL INCREASE AHEAD OF A MID-LEVEL SHORTWAVE TROUGH
TONIGHT. THE MOISTURE MAY BECOME DEEP ENOUGH IN THE NORTHWEST PART
AHEAD OF THE SLOW MOVING FRONT TO SUPPORT SHOWERS LATE. FORECASTED
SLIGHT CHANCE POPS IN THE NORTHWEST. THE NAM AND GFS SHOW THE
DIFFUSE FRONT AND ASSOCIATED MOISTURE NEAR THE AREA MONDAY AND
MONDAY NIGHT. THERE WILL BE A SERIES OF DIFFICULT TO TIME
SHORTWAVE TROUGHS IN THE MID-LEVEL FLOW. THE NAM AND GFS MOS ARE
IN GOOD AGREEMENT WITH POPS 40 TO 50 PERCENT.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
THE GFS AND ECMWF DISPLAY THE FRONT AND ASSOCIATED MOISTURE
LINGERING NEAR THE FORECAST AREA DURING MOST OF THE MEDIUM-RANGE
PERIOD. THE MODELS SHOW BROAD UPPER-LEVEL TROUGHING OVER THE AREA.
THE GFS AND ECMWF MOS SUPPORT CHANCE POPS THROUGH THE PERIOD.
LEANED TOWARD THE COOLER NAM AND ECMWF MOS TEMPERATURES TUESDAY
BECAUSE OF EXPECTED CLOUDINESS. USED AN AVERAGE OF THE GFS AND
ECMWF MOS DURING THE REST OF THE PERIOD.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
DEW POINTS BEGINNING TO DROP A BIT EARLY THIS MORNING AFTER A SEA
BREEZE BOUNDARY ROLLED THROUGH THE FORECAST AREA DURING LAST EVENING
WHICH HAD INCREASED DEW POINTS. WINDS HAVE BECOME LIGHT AND
VARIABLE. LATEST HRRR NOT INDICATING FOG...BUT LATEST GFS LAMP
GUIDANCE SUGGESTING POSSIBILITY OF MVFR VSBYS AT FOG PRONE AGS/OGB.
WILL INCLUDE IN A TEMPO GROUP...BUT CONFIDENCE LIMITED.
VFR CONDITIONS ARE EXPECTED AFTER 14Z TODAY. A DRY AND CAPPED
ATMOSPHERE IS EXPECTED TO CONTINUE OVER OUR FORECAST AREA...SO NO
CONVECTION EXPECTED.
EXTENDED AVIATION OUTLOOK...THE CHANCE FOR MAINLY DIURNAL CONVECTION
RETURNS MONDAY THROUGH WEDNESDAY...ALONG WITH SOME CHANCES OF LATE
NIGHT/EARLY MORNING FOG/STRATUS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1251 AM CDT SUN JUN 16 2013
...UPDATED AVIATION SECTION...
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 202 PM CDT SAT JUN 15 2013
IT APPEARS THAT PORTIONS OF WESTERN AND CENTRAL KANSAS COULD HAVE
A DECENT SHOT AT RECEIVING RAIN LATE THIS AFTERNOON INTO
TONIGHT. THE NAM AND GFS MODELS SHOW A TREND OF THUNDERSTORMS
DEVELOPING OVER EASTERN COLORADO AND MOVING INTO WESTERN KANSAS
DURING THE EVENING HOURS. THE HRRR HAS BEEN SHOWING THIS TREND AS
WELL. THE LATEST RUNS OF THAT MODEL ARE SHOWING WIDELY SCATTERED
THUNDERSTORMS DEVELOPING OVER WEST CENTRAL KANSAS LATE THIS
AFTERNOON AND MOVING INTO CENTRAL KANSAS WITH ANOTHER ROUND OF
THUNDERSTORMS THAT DEVELOP OVER EASTERN COLORADO THEN MOVING
ACROSS NORTHWEST AND WEST CENTRAL KANSAS LATER THIS EVENING. THINK
THAT THE TWO AREAS OF STORMS DEPICTED BY THE HRRR MAY BE CORRECT
GIVEN THE LOCATION OF THE FRONTAL BOUNDARY AND INCREASING
INSTABILITY. THE SUBSIDENCE CURRENTLY OVER THE REGION MAY QUASH
ANY LATE AFTERNOON CONVECTION BUT MODEL SOUNDINGS SHOW THE AREA
BECOMING UNCAPPED BY 00Z SO CAN`T TOTALLY RULE OUT A STORM OR TWO.
LATER TONIGHT AM EXPECTING THUNDERSTORMS TO MOVE OUT INTO WEST
CENTRAL AND PARTS OF SOUTHWEST KANSAS. HAVE INCREASED
PRECIPITATION CHANCES TO 50-55 PERCENT ESPECIALLY IN THE AREA
NORTH OF A LINE FROM SYRACUSE THROUGH MONTEZUMA, DODGE CITY AND
LARNED BASED OFF OF TRENDS IN THE HRRR. THE MODELS HINT AT A LOW
LEVEL JET DEVELOPING TONIGHT WHICH COULD HELP SUSTAIN THINGS INTO
THE LATE NIGHT HOURS BUT THINK WE WILL SEE A DECREASING TREND
AFTER 06Z.
SUNDAY SHOULD STAR OUT PARTLY TO MOSTLY SUNNY. ANOTHER WEAK
SHORTWAVE IS PROGGED TO MOVE OUT OF THE ROCKIES DURING THE LATE
AFTERNOON HOURS. HARD TO TELL WHERE EXACTLY THUNDERSTORMS WILL
INITIATE GIVEN THE UNCERTAINTY OF THE FRONTAL POSITION AND THE
POTENTIAL FOR ANY LEFTOVER OUTFLOW BOUNDARIES. WILL CONTINUE THE
PREVIOUS FORECAST TREND OF INCREASING POPS INTO THE CHANCE
CATEGORY BY LATE AFTERNOON. HIGH TEMPERATURES ON SUNDAY MAY ALSO
BE A LITTLE PROBLEMATIC DEPENDING ON HOW MUCH AND WHERE RAINFALL
OCCURS TONIGHT. WILL KEEP HIGHS IN THE UPPER 80S TO NEAR 90 IN
MOST AREAS WITH SOME LOW 90S OUT ALONG THE COLORADO BORDER.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 333 PM CDT SAT JUN 15 2013
FOR THE LATE SUNDAY THROUGH EARLY WEDNESDAY PERIOD, A FLAT UPPER
LEVEL RIDGE WILL BE SITUATED OVER THE SOUTHERN AND CENTRAL ROCKIES, WITH
WEST-NORTHWESTERLY CROSS-MOUNTAIN, MID LEVEL, FLOW ACROSS THE HIGH
PLAINS. THIS PATTERN WILL LEAD TO WEAK MID LEVEL CAPPING AND SURFACE
LEE TROUGHING, ALONG WITH LOW LEVEL MOISTURE RETURN ON THE HIGH
PLAINS. IN ADDITION, THE SOUTHERN BRANCH OF THE WESTERLIES AT MID
AND HIGH LEVELS WILL BE SITUATED FROM THE SOUTHWESTERN UNITED
STATES ACROSS THE CENTRAL PLAINS. ALL THESE FACTORS ARE FAVORABLE
FOR NOCTURNAL STORM CLUSTERS TO DEVELOP THIS TIME OF YEAR ON THE FRONT
RANGE AND HIGH PLAINS EVERY EVENING AND NIGHTTIME. THEREFORE,
CHANCES OF THUNDERSTORMS WITH BENEFICIAL RAINS LOOK HIGH. BUT THE
EXACT PLACEMENT OF THE RAIN AREAS IS NOT KNOWN WITH HIGH
CONFIDENCE. LOTS OF COOL OUTFLOW FROM THE THUNDERSTORM CLUSTERS
WILL LEAD TO COOLER HIGH TEMPERATURES EACH DAY THROUGH TUESDAY.
THE BEST CHANCES FOR RAIN APPEAR TO BE SUNDAY AND MONDAY NIGHTS AS
MUCH MORE STABLE AIR COULD BE IN PLACE BY TUESDAY.
FOR THE WEDNESDAY TO FRIDAY PERIOD, UPPER LEVEL RIDGING IS EXPECTED
TO REDEVELOP ACROSS EASTERN KANSAS, MISSOURI AND OKLAHOMA, WITH
UPPER LEVEL TROUGHING OVER THE NORTHERN ROCKIES. THIS WILL LEAD TO
MUCH DRIER WEATHER AND WARMER TEMPERATURES, WITH HIGHS APPROACHING
100F BY FRIDAY AND SATURDAY. ISOLATED THUNDERSTORMS CANNOT BE RULED
OUT EACH AFTERNOON AND EVENING ALONG THE SOUTHERN EDGE OF THE WESTERLIES
NEAR THE LEE TROUGH IN WESTERN KANSAS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1244 AM CDT SUN JUN 16 2013
SCATTERED THUNDERSTORMS AND MVFR/IFR CONDITIONS WILL CONTINUE
ACROSS DDC AND HYS TERMINALS OVER THE NEXT COUPLE HOURS.
THEREAFTER, VFR CONDITIONS SHOULD PREVAIL FOR THE REMAINDER OF THE
MORNING HOURS INTO THE AFTERNOON. GUSTY WINDS WILL ACCOMPANY THESE
STORMS BECOMING LIGHT AND VARIABLE DURING THE EARLY MORNING HOURS.
WINDS THEN INCREASE FROM THE SOUTH AT 10 TO 15 KNOTS IN THE LATE
MORNING INTO THE AFTERNOON HOURS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 64 86 62 82 / 60 30 30 30
GCK 64 86 62 81 / 50 20 40 30
EHA 64 87 62 81 / 40 20 40 40
LBL 64 86 63 81 / 50 30 40 30
HYS 64 85 62 81 / 60 20 30 20
P28 68 88 64 83 / 80 60 30 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GERARD
LONG TERM...FINCH
AVIATION...HOVORKA_42
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
548 AM EDT SUN JUN 16 2013
.SYNOPSIS...
SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY...WITH THE POSSIBILITY
FOR PERIODIC RAIN CONTINUING MONDAY AND TUESDAY. CONDITIONS
SHOULD THEN DRY OUT FOR THE REST OF THE WORK WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
LINE OF SHOWERS AND THUNDERSTORMS ACROSS LOWER MICHIGAN AND NORTHERN
INDIANA HAS MANAGED TO HOLD UP FAIRLY WELL CONSIDERING THE TIME OF
DAY. HOWEVER...DO NOT THINK THIS LINE WILL BE ABLE TO MAINTAIN
ITSELF ALL THE WAY INTO NORTHEASTERN OHIO AND NORTHWESTERN
PENNSYLVANIA. 04Z HRRR INDICATES THE LINE MAY PASS TO THE NORTH
AROUND SUNRISE. NEVERTHELESS...SOME LIGHT SPRINKLES ARE EXPECTED
OVERNIGHT...AND COVERAGE OF SHOWERS WILL INCREASE AS THE MORNING
PROGRESSES. CONTINUED PREVIOUS FORECAST WITH LIKELY POPS MOVING
FROM NORTH TO SOUTH DURING THE DAY. CANNOT RULE OUT A
STRONG/SEVERE THUNDERSTORM...BUT AM NOT OVERLY IMPRESSED WITH THE
SETUP. MODEL SOUNDINGS SHOW MODERATE LEVELS OF INSTABILITY AND
SHEAR ALONG THE FRONT ITSELF...BUT LOOKING AT HIGH-RESOLUTION
MODEL REFLECTIVITIES...MOST OF THE PRECIPITATION WILL OCCUR WELL
AHEAD OF THE FRONT ITSELF. MODEL SOUNDINGS IN THE REGIONS WITH
PRECIPITATION SHOW A BIT LESS INSTABILITY DUE TO WEAK LOW-LEVEL
LAPSE RATES. WHILE SHOWERS WILL CONTINUE INTO THE EVENING...THINK
THAT MOST RAINFALL ACTIVITY WILL BE CONFINED TO LOCATIONS SOUTH OF
THE MASON-DIXON LINE AFTER MIDNIGHT. WITH THE WIDESPREAD CLOUD
COVER...DAYTIME TEMPS WILL BE A FEW DEGREES COOLER THAN
YESTERDAY...AND OVERNIGHT LOWS SHOULD BE SIMILAR TO CURRENT
READINGS.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
HAVE BACKED OFF POPS ON MONDAY DOWN TO SLIGHT CHANCE. FORECAST AREA
SHOULD BE IN THE DRY REGION BETWEEN FRONTS TO THE NORTH AND
SOUTH...AND DO NOT SEE MUCH OF A TRIGGER TO GET PRECIP GOING. MONDAY
NIGHT AND TUESDAY THE NAM/SREF ARE AGGRESSIVE SWEEPING THE NORTHERN
FRONT ACROSS THE REGION AND BRINGING WIDESPREAD PRECIPITATION. WITH
THE ECMWF SHOWING MORE CONSISTENCY...KEEPING THE NORTHERN FRONT DRY
AND FOCUSING PRECIPITATION ALONG THE SOUTHERN FRONT...AND THE GFS
AND GEFS COMING INTO LINE WITH THE ECMWF SOLUTION...HAVE BACKED OFF
POPS ACROSS THE NORTHERN HALF OF THE REGION FOR MON NIGHT/TUES.
ONCE THE FRONT MOVES OFF TO THE EAST...THE ENTIRE AREA SHOULD BE
DRY TUESDAY NIGHT AND WEDNESDAY WITH HIGH PRESSURE MOVING IN FROM
MICHIGAN. LIGHT NORTHERLY FLOW THROUGH THIS TIME PERIOD SHOULD
KEEP TEMPERATURES A FEW DEGREES BELOW NORMAL.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
LATEST GFS AND ECMWF DETERMINISTIC SOLNS AGREED GENLY IN
DEPICTIONS OF THE PROGGED FLOW PTN OVR THE ERN CONUS FOR THE
LATTER HALF OF THE WEEK...WITH ECMWF AMPLIFYING THE PTN CLOSER TO
GFS WITH A RIDGE AXIS EXTENDING FM THE SRN PLNS ACRS THE GREAT
LAKES.
THE LONG TERM FORECAST THUS CONSERVATIVELY FEATURES TEMPS
GRADUALLY WARMING TO SLIGHTLY ABOVE THE SEASONAL AVERAGES BY THE
WEEKEND. PCPN CHCS WERE FORECAST AOB CLIMO NMBRS...BUT WERE GENLY
INCRSD USING A GFS/ECMWF BLEND FOR SHRTWV TIMING INTO THE WEEKEND.
&&
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
AN APPRHG SHRTWV AND ASSOCIATED CDFNT WL BRING SHWRS AND INCRSD
EMBEDDED TSTM CHCS TDA. FOR NOW...GIVEN A LACK OF CONFIDENCE IN
INSTABILITY PROGS...WL KP MENTION OF THUNDER OUT OF ANY SPECIFIC
TAF SITE. A GRADUAL DETERIORATION TO MVFR CAN BE EXPECTED...WITH
ISOLD IFR IN HEAVIER SHWRS.
.OUTLOOK.../MONDAY THROUGH THURSDAY/...
PERIODIC RESTRICTIONS ARE ANTICIPATED THROUGH TUESDAY AS ANOTHER
LOW APPRCHS AND CROSSES THE REGION. BLDG HIGH PRES SHOULD RTN VFR
CONDITIONS FOR WEDNESDAY AND THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
330 AM EDT SUN JUN 16 2013
.SYNOPSIS...
SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY...WITH THE POSSIBILITY
FOR RAIN CONTINUING MONDAY AND TUESDAY. CONDITIONS SHOULD THEN DRY
OUT FOR THE REST OF THE WORK WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
LINE OF SHOWERS AND THUNDERSTORMS ACROSS LOWER MICHIGAN AND NORTHERN
INDIANA HAS MANAGED TO HOLD UP FAIRLY WELL CONSIDERING THE TIME OF
DAY. HOWEVER...DO NOT THINK THIS LINE WILL BE ABLE TO MAINTAIN
ITSELF ALL THE WAY INTO NORTHEASTERN OHIO AND NORTHWESTERN
PENNSYLVANIA. 04Z HRRR INDICATES THE LINE MAY PASS TO THE NORTH
AROUND SUNRISE. NEVERTHELESS...SOME LIGHT SPRINKLES ARE EXPECTED
OVERNIGHT...AND COVERAGE OF SHOWERS WILL INCREASE AS THE MORNING
PROGRESSES. CONTINUED PREVIOUS FORECAST WITH LIKELY POPS MOVING
FROM NORTH TO SOUTH DURING THE DAY. CANNOT RULE OUT A
STRONG/SEVERE THUNDERSTORM...BUT AM NOT OVERLY IMPRESSED WITH THE
SETUP. MODEL SOUNDINGS SHOW MODERATE LEVELS OF INSTABILITY AND
SHEAR ALONG THE FRONT ITSELF...BUT LOOKING AT HIGH-RESOLUTION
MODEL REFLECTIVITIES...MOST OF THE PRECIPITATION WILL OCCUR WELL
AHEAD OF THE FRONT ITSELF. MODEL SOUNDINGS IN THE REGIONS WITH
PRECIPITATION SHOW A BIT LESS INSTABILITY DUE TO WEAK LOW-LEVEL
LAPSE RATES. WHILE SHOWERS WILL CONTINUE INTO THE EVENING...THINK
THAT MOST RAINFALL ACTIVITY WILL BE CONFINED TO LOCATIONS SOUTH OF
THE MASON-DIXON LINE AFTER MIDNIGHT. WITH THE WIDESPREAD CLOUD
COVER...DAYTIME TEMPS WILL BE A FEW DEGREES COOLER THAN
YESTERDAY...AND OVERNIGHT LOWS SHOULD BE SIMILAR TO CURRENT
READINGS.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
HAVE BACKED OFF POPS ON MONDAY DOWN TO SLIGHT CHANCE. FORECAST AREA
SHOULD BE IN THE DRY REGION BETWEEN FRONTS TO THE NORTH AND
SOUTH...AND DO NOT SEE MUCH OF A TRIGGER TO GET PRECIP GOING. MONDAY
NIGHT AND TUESDAY THE NAM/SREF ARE AGGRESSIVE SWEEPING THE NORTHERN
FRONT ACROSS THE REGION AND BRINGING WIDESPREAD PRECIPITATION. WITH
THE ECMWF SHOWING MORE CONSISTENCY...KEEPING THE NORTHERN FRONT DRY
AND FOCUSING PRECIPITATION ALONG THE SOUTHERN FRONT...AND THE GFS
AND GEFS COMING INTO LINE WITH THE ECMWF SOLUTION...HAVE BACKED OFF
POPS ACROSS THE NORTHERN HALF OF THE REGION FOR MON NIGHT/TUES.
ONCE THE FRONT MOVES OFF TO THE EAST...THE ENTIRE AREA SHOULD BE
DRY TUESDAY NIGHT AND WEDNESDAY WITH HIGH PRESSURE MOVING IN FROM
MICHIGAN. LIGHT NORTHERLY FLOW THROUGH THIS TIME PERIOD SHOULD
KEEP TEMPERATURES A FEW DEGREES BELOW NORMAL.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
LATEST GFS AND ECMWF DETERMINISTIC SOLNS AGAIN DIVERGE
SIGNIFICANTLY IN DEPICTIONS OF THE PROGGED FLOW PTN OVR THE ERN
CONUS FOR THE LATTER HALF OF THE WEEK. GFS FORECASTS A MORE
AMPLIFIED HT FIELD WITH A RIDGE AXIS EXTENDING FM THE SRN PLNS
ACRS THE GREAT LAKES.
WITH THE ECMWF EXHIBITING A MORE CONSISTENT SOLN THAT IS CLOSER
TO ENSEMBLE MEANS...THE LONG TERM FORECAST IS A MORE MODERATE
PROGNOSIS FEATURING TEMPS GRADUALLY WARMING TO NR/JUST ABOVE THE
SEASONAL AVERAGES BY THE WEEKEND. PCPN CHCS WERE FORECAST AOB
CLIMO NMBRS...BUT WERE GENLY INCRSD USING A GFS/ECMWF BLEND FOR
SHRTWV TIMING INTO THE WEEKEND. ALL OF WHICH IS GENLY FEATURED VIA
HPC GUIDANCE...MINOR TWEAKS TO WHICH SUFFICED.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
AN APPRHG SHRTWV AND ASSOCIATED CDFNT WL BRING SHWRS AND INCRSG
CHCS FOR TSTMS TDA. FOR NOW...GIVEN A LACK OF CONFIDENCE IN
INSTABILITY PROGS...WL KP MENTION OF THUNDER OUT OF ANY SPECIFIC
TAF SITE. A GRADUAL DETERIORATION TO MVFR CAN BE EXPECTED...WITH
ISOLD IFR IN HEAVIER SHWRS.
.OUTLOOK.../MONDAY THROUGH THURSDAY/...
PERIODIC RESTRICTIONS ARE ANTICIPATED THROUGH TUESDAY AS ANOTHER
LOW APPRCHS AND CROSSES THE REGION. BLDG HIGH PRES SHOULD RTN VFR
CONDITIONS FOR WEDNESDAY AND THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
348 AM EDT SUN JUN 16 2013
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 432 PM EDT SAT JUN 15 2013
WEAKENING UPPER RIDGE AXIS IS STILL OVER THE WESTERN GREAT
LAKES...WHILE A LARGE UPPER LOW IS SPINNING OVER CENTRAL
SASKATCHEWAN. THERE AREA A COUPLE SUBTLE DISTURBANCES ROUNDING THE
RIDGE. THE FIRST ONE IS CURRENTLY EXITING EASTERN UPPER MICHIGAN.
THIS WAVE COMBINED WITH BROAD WARM AIR ADVECTION TO PRODUCE
THE SHOWERS THIS MORNING OVER THE WEST AND THEN THE DIMINISHING
SHOWERS OVER THE EAST THIS AFTERNOON. THE NEXT WAVE IS CURRENTLY
ASSOCIATED WITH THE CONVECTION IN NORTHERN IOWA AND SOUTHERN
MINNESOTA AND MOVING TO THE EAST-NORTHEAST. AT THE SURFACE...A
TROUGH IS CURRENTLY STRETCHING SOUTH ACROSS EASTERN MINNESOTA FROM
THE LOW IN CENTRAL SASKATCHEWAN. POCKET OF MLCAPE VALUES AROUND
1000 J/KG IS LOCATED AHEAD OF THIS TROUGH IN WESTERN WISCONSIN AND
STARTING TO NOSE NORTHEAST INTO WESTERN UPPER MICHIGAN. SHOWERS AND
THUNDERSTORMS HAVE STARTED TO DEVELOP NORTH OF THE TWIN CITIES...AS
HINTED AT BY MORNING RUNS OF THE HRRR...AND HAVE BEEN LIFTING
NORTHEAST.
FOR THE REST OF THIS AFTERNOON AND TONIGHT THE FORECAST DEPENDS ON
TWO FEATURES...THE TROUGH MOVING THROUGH THE U.P. THIS EVENING AND
THE SHORTWAVE ASSOCIATED WITH THE DECAYING CONVECTION IN SOUTHEAST
MN. THEY BOTH SEEM TO BE INTERACTING OVER THE LAST COUPLE OF HOURS
WITH THE DEVELOPMENT OF THUNDERSTORMS NORTH OF THE TWIN CITIES AND
INTO WEST CENTRAL WISCONSIN. AS INDICATED BY THE HRRR THIS
MORNING...WOULD EXPECT THESE THUNDERSTORMS TO CONTINUE DEVELOP AND
PUSH NORTHEAST INITIALLY BEFORE THE STORM MOTIONS TAKE THEM MORE
EASTERLY AS IT ROUNDS THE RIDGE. ML CAPES SHOULD CONTINUE TO PUSH
NORTHEAST TOWARDS THE WISCONSIN BORDER...AS THE LOW CLOUDS BEGIN TO
THIN AND INCREASE HEATING. THE ONE CONCERN WILL BE THE THICKENING
HIGH CLOUDS ON THE NORTH SIDE OF THE CONVECTION MAY BE ENOUGH TO
LIMIT THE NORTHWARD EXTENT OF THE INSTABILITY. WITH THE SHORTWAVE
ALSO ROUNDING THE RIDGE...THAT SHOULD FOCUS THE BEST FORCING ACROSS
CENTRAL WISCONSIN. THEREFORE...WOULD EXPECT THE BEST CHANCE FOR
SHOWERS AND THUNDERSTORMS LATE THIS AFTERNOON AND EVENING OVER THE
SOUTHERN HALF OF THE CWA...ESPECIALLY NEAR THE WISCONSIN BORDER
WHERE THE BEST INSTABILITY WILL BE LOCATED AND STORM MOTION WOULD
TRACK THE THUNDERSTORMS. AT THIS POINT...WOULD EXPECT HEAVY RAIN TO
BE THE MAIN THREAT SINCE NCAPE SHOULD REMAIN BELOW 0.1 AND DCAPE
VALUES STRUGGLE TO RISE ABOVE 700 J/KG AS THE LOW CLOUDS OVER THE
SOUTHWEST DISSIPATE.
FARTHER NORTHWEST...THE UPPER LOW SPINNING IN CENTRAL SASKATCHEWAN
WILL LIKELY SPARK SOME SHOWERS AND THUNDERSTORMS ALONG THE
MN/ND/CANADA BORDER THIS AFTERNOON WHICH WILL TRACK EAST THIS
EVENING. WITH THE LOSS OF DIURNAL HEATING...WOULD EXPECT THEM TO
DIMINISH AS THEY APPROACH NORTHERN LAKE SUPERIOR. BUT WITH THE
CLOSE PROXIMITY OF THE UPPER LEVEL SHORTWAVES...DEEPER MOISTURE AND
STEEPER LAPSE RATES...WILL HOLD ONTO SLIGHT CHANCE POPS AS THAT
MOVES ACROSS THE NORTHERN LAKE TONIGHT.
OTHERWISE...ONCE THE THE TROUGH AND CONVECTION SLIDE THROUGH...DRY
MID LEVEL AIR WILL SURGE OVER THE AREA AND LEAD TO A FAIRLY QUIET
NIGHT WITH DECREASING CLOUDS FROM WEST TO EAST. WITH THE MOIST
SOUTHERLY FLOW OFF LAKE MICHIGAN AND THE POTENTIAL FOR SOME FOG OFF
THE LAKE WITH THE SHOWERS UPSTREAM...HAVE ADDED IN FOG OVER EASTERN
UPPER MICHIGAN. ALSO ADDED A MENTION OVER CENTRAL/EASTERN LAKE
SUPERIOR...ALONG WITH THE KEWEENAW...SINCE THERE IS A DENCENT
CONSISTENCY IN THE MODELS AND THERE ARE 50S AND LOW 60S DEWPOINTS
MOVING OVER WESTERN/CENTRAL LAKE SUPERIOR THIS AFTERNOON.
UNFORTUNATELY...CLOUDS HAVE OBSCURED THE LAKE TO SEE IF ANY FOG IS
GOING...BUT SHIP OBS HAVE YET TO REPORT FOG.
EXPECT SUNDAY TO START OFF ON THE NICE SIDE WITH A DECENT AMOUNT OF
SUNSHINE...AS THE AREA IS STILL UNDER THE 900-500MB DRY AIR. THIS
DRY AIR WILL SLIDE EAST-SOUTHEAST THROUGH THE DAY AS THE UPPER
LOW WEST OF LAKE WINNIPEG SHEARS OFF AND STARTS TO SEND PIECES OF
ENERGY ACROSS THE AREA. THE ABUNDANT SUNSHINE TO START THE DAY WILL
ALLOW TEMPERATURES TO QUICKLY RISE INTO THE 70S...WITH A FEW
VALUES IN THE LOWER 80S OVER THE SOUTH CENTRAL.
AS FOR FORCING FEATURES...SURFACE LOW ASSOCIATED WITH THE ELONGATED
TROUGH WILL BE RE-FOCUSING EAST OF LAKE SUPERIOR SUNDAY MORNING AND
THEN PUSHING EAST INTO SOUTHEASTERN ONTARIO ON SUNDAY AFTERNOON...AS
THE MAIN AREA OF SHORTWAVE ENERGY FOLLOWS THAT SAME TRACK. THIS WILL
LEAVE A SURFACE TROUGH OR COLD FRONT BACK ACROSS LAKE
SUPERIOR...WHICH WILL START TO DROP SOUTH OVER UPPER MICHIGAN DURING
THE AFTERNOON HOURS. AS THAT OCCURS...THE INCREASING 850-750MB
MOISTURE SHOULD SPARK SOME HIGH BASED DIURNAL CU. WITH MODEL
CONSENSUS ML CAPE VALUES AROUND 400J/KG...QUESTION COMES TO IF THERE
WILL BE ENOUGH MOISTURE FOR SHOWERS TO DEVELOP. MARGINAL MID-LEVEL
MOISTURE AND DECENT DRY AIR ABOVE 650MB WILL LIKELY
LIMIT THINGS...BUT DID INCLUDE SLIGHTS AND LOW END CHANCES FROM MID
AFTERNOON ON IN CASE THE DEEPER MOISTURE WITH THE TROUGH ARRIVES A
LITTLE QUICKER. IF THERE WASN/T THE INVERTED V LOOK TO THE
SOUNDINGS WITH THE MIXING TO 800-700MB WOULD HAVE CONSIDERED THE
HIGHER INSTABILITY VALUES SEEN IN THE NAM...ML CAPE VALUES AROUND
1000 J/KG...AND BOOSTED POPS UP MORE. EXPECT THE SEVERE THREAT TO BE
LIMITED WITH THESE SHOWERS/THUNDERSTORMS UNLESS THE NAM SOLUTION
VERIFIES. THIS IS DUE TO THE CAPE IS FAIRLY TALL/SKINNY WITH NCAPE
VALUES BELOW 0.1 ALTHOUGH EFFECTIVE SHEAR VALUES ARE IN THE 30-40KT
RANGE. GUSTY WINDS COULD BE A CONCERN WITH THAT INVERTED V
LOOK...DCAPE VALUES OVER 750 J/KG OVER THE SOUTH CENTRAL...AND
EXISTING WINDS GUSTING TO 20-25KTS OVER THE WESTERN CWA.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 347 AM EDT SUN JUN 16 2013
THE WEATHER IN THE LONG TERM WILL NOT CHANGE DRAMATICALLY...WITH NO
SIGNIFICANT PATTERN CHANGES IN SIGHT. EXPECT 500MB LOW PRESSURE TO
REMAIN OVER NE CANADA AND HUDSON BAY THROUGH THE ENTIRE PERIOD.
WILL START OUT MONDAY WITH A GOOD AMOUNT OF CLOUD COVER...THANKS TO
COOL N FLOW OFF LAKE SUPERIOR /850MB TEMPS NEAR 7C ALONG THE SHORE/
AND THE 500MB SHORTWAVE BREAKING UP THE WEAK NW TO ZONAL FLOW. THE
SHORTWAVE WILL SLIDE IN FROM NE MN AND ONTARIO EARLY...WITH
IMPROVING CONDITIONS BY EARLY AFTERNOON. THE 500MB LOW SPINNING NEAR
JAMES BAY ON MONDAY WILL SWING ANOTHER WAVE DOWN FROM ONTARIO MONDAY
NIGHT...WITH VERY LITTLE IMPACT AS HIGH PRESSURE DOMINATES AT THE
SFC. FEW CLOUDS...LIGHT WINDS...AND COOL TEMPS FALLING INTO THE LOW
TO MID 30S SHOULD BE ENOUGH FOR PATCHY FROST ACROSS THE INTERIOR W
HALF OF UPPER MI AFTER MIDNIGHT MONDAY NIGHT INTO EARLY TUESDAY
MORNING.
DRY WEATHER SHOULD THEN BE THE RULE THROUGH AT LEAST WEDNESDAY...AS
THE SFC HIGH SLOWLY SINKS ACROSS LOWER MI. EXPECT A SLOW AND STEADY
WARMUP EACH DAY...WITH LAKE BREEZES LIKELY EACH AFTERNOON...COOLING
DOWN NEAR SHORE AREAS. WAA WILL INTENSIFY WEDNESDAY...WITH 850MB
TEMPS RISING TO AROUND 10C BY THE END OF THE DAY.
THERE COULD BE A SMALL CHANCE OF SHOWERS WEDNESDAY NIGHT INTO EARLY
THURSDAY MORNING...OR MORE THAN LIKELY JUST INCREASED CLOUD
COVER...ASSOCIATED WITH YET ANOTHER WAVE SWEEPING ACROSS THE UPPER
GREAT LAKES ON OUR QUICK NW FLOW ALOFT. ALTHOUGH IT LOOKS LIKE A
PRETTY WET PERIOD POP WISE FOR WEDNESDAY NIGHT THROUGH SUNDAY...IT
WILL BE A LOW CONFIDENCE FORECAST BEYOND THIS PERIOD. THE CONSENSUS
IS TO CONTINUE TO KEEP THE FAR EASTERN AREAS A BIT DRIER...WITH A SFC
LOW ORGANIZING ACROSS THE PLAINS STATES FOR THE END OF THE WORK WEEK.
THE BEST DYNAMICS LOOK TO STAY TO OUR SOUTH...AS THE SFC LOW SLIDES
TOWARD LAKE MI AND LOWER MI SATURDAY NIGHT. IF THAT OCCURS...IT WILL
GIVE THE EAST END OF UPPER MI A GOOD CHANCE OF RECEIVING A WETTING
RAIN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 133 AM EDT SUN JUN 16 2013
FOG AND LOW CLOUDS WILL MAKE THE FCST A CHALLENGE THIS MORNING. TEMPO
IFR VIS WILL OCCUR OVERNIGHT AT IWD AND SAW WITH FOG AND THEN VFR
CONDITIONS ARE EXPECTED THROUGH THE REST OF THE PERIOD WITH MIXING
TAKING PLACE DURING THE DAY. AT CMX EXPECT LIFR TO VLIFR VSBY IN FOG
AS IT ADVECTS IN OFF THE LAKE. THIS SHOULD MIX OUT BY MORNING WITH
VFR CONDITIONS EXPECTED THEN THROUGH REST OF PERIOD AT CMX.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 432 PM EDT SAT JUN 15 2013
EXPECT WINDS LESS THAN 20KT ACROSS LAKE SUPERIOR THRU THE FCST
PERIOD AS PRES GRADIENT WILL REMAIN GENERALLY WEAK...TYPICAL OF THE
WARM SEASON. THERE MAY BE SOME FOG PATCHES THRU SUN EVENING BEFORE
DRIER AIR BEGINS TO SURGE S INTO THE AREA. IF SOME RAINFALL OCCURS
OVER THE LAKE...FOG WILL BE MORE LIKELY TO FORM AND BECOME MORE
WIDESPREAD/DENSE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
DENSE FOG ADVISORY UNTIL 8 AM EDT THIS MORNING FOR LMZ221-248-
250.
&&
$$
SHORT TERM...SRF
LONG TERM...KF
AVIATION...07/JV
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
142 AM EDT SUN JUN 16 2013
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 432 PM EDT SAT JUN 15 2013
WEAKENING UPPER RIDGE AXIS IS STILL OVER THE WESTERN GREAT
LAKES...WHILE A LARGE UPPER LOW IS SPINNING OVER CENTRAL
SASKATCHEWAN. THERE AREA A COUPLE SUBTLE DISTURBANCES ROUNDING THE
RIDGE. THE FIRST ONE IS CURRENTLY EXITING EASTERN UPPER MICHIGAN.
THIS WAVE COMBINED WITH BROAD WARM AIR ADVECTION TO PRODUCE
THE SHOWERS THIS MORNING OVER THE WEST AND THEN THE DIMINISHING
SHOWERS OVER THE EAST THIS AFTERNOON. THE NEXT WAVE IS CURRENTLY
ASSOCIATED WITH THE CONVECTION IN NORTHERN IOWA AND SOUTHERN
MINNESOTA AND MOVING TO THE EAST-NORTHEAST. AT THE SURFACE...A
TROUGH IS CURRENTLY STRETCHING SOUTH ACROSS EASTERN MINNESOTA FROM
THE LOW IN CENTRAL SASKATCHEWAN. POCKET OF MLCAPE VALUES AROUND
1000 J/KG IS LOCATED AHEAD OF THIS TROUGH IN WESTERN WISCONSIN AND
STARTING TO NOSE NORTHEAST INTO WESTERN UPPER MICHIGAN. SHOWERS AND
THUNDERSTORMS HAVE STARTED TO DEVELOP NORTH OF THE TWIN CITIES...AS
HINTED AT BY MORNING RUNS OF THE HRRR...AND HAVE BEEN LIFTING
NORTHEAST.
FOR THE REST OF THIS AFTERNOON AND TONIGHT THE FORECAST DEPENDS ON
TWO FEATURES...THE TROUGH MOVING THROUGH THE U.P. THIS EVENING AND
THE SHORTWAVE ASSOCIATED WITH THE DECAYING CONVECTION IN SOUTHEAST
MN. THEY BOTH SEEM TO BE INTERACTING OVER THE LAST COUPLE OF HOURS
WITH THE DEVELOPMENT OF THUNDERSTORMS NORTH OF THE TWIN CITIES AND
INTO WEST CENTRAL WISCONSIN. AS INDICATED BY THE HRRR THIS
MORNING...WOULD EXPECT THESE THUNDERSTORMS TO CONTINUE DEVELOP AND
PUSH NORTHEAST INITIALLY BEFORE THE STORM MOTIONS TAKE THEM MORE
EASTERLY AS IT ROUNDS THE RIDGE. ML CAPES SHOULD CONTINUE TO PUSH
NORTHEAST TOWARDS THE WISCONSIN BORDER...AS THE LOW CLOUDS BEGIN TO
THIN AND INCREASE HEATING. THE ONE CONCERN WILL BE THE THICKENING
HIGH CLOUDS ON THE NORTH SIDE OF THE CONVECTION MAY BE ENOUGH TO
LIMIT THE NORTHWARD EXTENT OF THE INSTABILITY. WITH THE SHORTWAVE
ALSO ROUNDING THE RIDGE...THAT SHOULD FOCUS THE BEST FORCING ACROSS
CENTRAL WISCONSIN. THEREFORE...WOULD EXPECT THE BEST CHANCE FOR
SHOWERS AND THUNDERSTORMS LATE THIS AFTERNOON AND EVENING OVER THE
SOUTHERN HALF OF THE CWA...ESPECIALLY NEAR THE WISCONSIN BORDER
WHERE THE BEST INSTABILITY WILL BE LOCATED AND STORM MOTION WOULD
TRACK THE THUNDERSTORMS. AT THIS POINT...WOULD EXPECT HEAVY RAIN TO
BE THE MAIN THREAT SINCE NCAPE SHOULD REMAIN BELOW 0.1 AND DCAPE
VALUES STRUGGLE TO RISE ABOVE 700 J/KG AS THE LOW CLOUDS OVER THE
SOUTHWEST DISSIPATE.
FARTHER NORTHWEST...THE UPPER LOW SPINNING IN CENTRAL SASKATCHEWAN
WILL LIKELY SPARK SOME SHOWERS AND THUNDERSTORMS ALONG THE
MN/ND/CANADA BORDER THIS AFTERNOON WHICH WILL TRACK EAST THIS
EVENING. WITH THE LOSS OF DIURNAL HEATING...WOULD EXPECT THEM TO
DIMINISH AS THEY APPROACH NORTHERN LAKE SUPERIOR. BUT WITH THE
CLOSE PROXIMITY OF THE UPPER LEVEL SHORTWAVES...DEEPER MOISTURE AND
STEEPER LAPSE RATES...WILL HOLD ONTO SLIGHT CHANCE POPS AS THAT
MOVES ACROSS THE NORTHERN LAKE TONIGHT.
OTHERWISE...ONCE THE THE TROUGH AND CONVECTION SLIDE THROUGH...DRY
MID LEVEL AIR WILL SURGE OVER THE AREA AND LEAD TO A FAIRLY QUIET
NIGHT WITH DECREASING CLOUDS FROM WEST TO EAST. WITH THE MOIST
SOUTHERLY FLOW OFF LAKE MICHIGAN AND THE POTENTIAL FOR SOME FOG OFF
THE LAKE WITH THE SHOWERS UPSTREAM...HAVE ADDED IN FOG OVER EASTERN
UPPER MICHIGAN. ALSO ADDED A MENTION OVER CENTRAL/EASTERN LAKE
SUPERIOR...ALONG WITH THE KEWEENAW...SINCE THERE IS A DENCENT
CONSISTENCY IN THE MODELS AND THERE ARE 50S AND LOW 60S DEWPOINTS
MOVING OVER WESTERN/CENTRAL LAKE SUPERIOR THIS AFTERNOON.
UNFORTUNATELY...CLOUDS HAVE OBSCURED THE LAKE TO SEE IF ANY FOG IS
GOING...BUT SHIP OBS HAVE YET TO REPORT FOG.
EXPECT SUNDAY TO START OFF ON THE NICE SIDE WITH A DECENT AMOUNT OF
SUNSHINE...AS THE AREA IS STILL UNDER THE 900-500MB DRY AIR. THIS
DRY AIR WILL SLIDE EAST-SOUTHEAST THROUGH THE DAY AS THE UPPER
LOW WEST OF LAKE WINNIPEG SHEARS OFF AND STARTS TO SEND PIECES OF
ENERGY ACROSS THE AREA. THE ABUNDANT SUNSHINE TO START THE DAY WILL
ALLOW TEMPERATURES TO QUICKLY RISE INTO THE 70S...WITH A FEW
VALUES IN THE LOWER 80S OVER THE SOUTH CENTRAL.
AS FOR FORCING FEATURES...SURFACE LOW ASSOCIATED WITH THE ELONGATED
TROUGH WILL BE RE-FOCUSING EAST OF LAKE SUPERIOR SUNDAY MORNING AND
THEN PUSHING EAST INTO SOUTHEASTERN ONTARIO ON SUNDAY AFTERNOON...AS
THE MAIN AREA OF SHORTWAVE ENERGY FOLLOWS THAT SAME TRACK. THIS WILL
LEAVE A SURFACE TROUGH OR COLD FRONT BACK ACROSS LAKE
SUPERIOR...WHICH WILL START TO DROP SOUTH OVER UPPER MICHIGAN DURING
THE AFTERNOON HOURS. AS THAT OCCURS...THE INCREASING 850-750MB
MOISTURE SHOULD SPARK SOME HIGH BASED DIURNAL CU. WITH MODEL
CONSENSUS ML CAPE VALUES AROUND 400J/KG...QUESTION COMES TO IF THERE
WILL BE ENOUGH MOISTURE FOR SHOWERS TO DEVELOP. MARGINAL MID-LEVEL
MOISTURE AND DECENT DRY AIR ABOVE 650MB WILL LIKELY
LIMIT THINGS...BUT DID INCLUDE SLIGHTS AND LOW END CHANCES FROM MID
AFTERNOON ON IN CASE THE DEEPER MOISTURE WITH THE TROUGH ARRIVES A
LITTLE QUICKER. IF THERE WASN/T THE INVERTED V LOOK TO THE
SOUNDINGS WITH THE MIXING TO 800-700MB WOULD HAVE CONSIDERED THE
HIGHER INSTABILITY VALUES SEEN IN THE NAM...ML CAPE VALUES AROUND
1000 J/KG...AND BOOSTED POPS UP MORE. EXPECT THE SEVERE THREAT TO BE
LIMITED WITH THESE SHOWERS/THUNDERSTORMS UNLESS THE NAM SOLUTION
VERIFIES. THIS IS DUE TO THE CAPE IS FAIRLY TALL/SKINNY WITH NCAPE
VALUES BELOW 0.1 ALTHOUGH EFFECTIVE SHEAR VALUES ARE IN THE 30-40KT
RANGE. GUSTY WINDS COULD BE A CONCERN WITH THAT INVERTED V
LOOK...DCAPE VALUES OVER 750 J/KG OVER THE SOUTH CENTRAL...AND
EXISTING WINDS GUSTING TO 20-25KTS OVER THE WESTERN CWA.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 432 PM EDT SAT JUN 15 2013
THE FIRST HALF OF THE UPCOMING WEEK WILL FEATURE NW FLOW INTO THE
UPPER GREAT LAKES BTWN A RIDGE DRIFTING FROM THE ROCKIES TO THE
PLAINS AND A BROAD TROF OVER ERN NAMERICA. LATER IN THE WEEK...RIDGE
PROGRESSING INTO THE PLAINS WILL BE SUPPRESSED BY SHORTWAVE ENERGY
EJECTING E FROM A TROF OVER THE PACIFIC NW. WHILE THERE MAY BE SOME
LIMITED OPPORTUNITIES FOR PCPN...NW FLOW WILL NOT SUPPORT
WIDESPREAD/SIGNIFICANT RAINFALL THRU MID WEEK. THE LATE WEEK PERIOD
COULD THEN BECOME ACTIVE WITH BETTER PCPN PROSPECTS AS SHORTWAVES
EJECT E ACROSS THE NRN PLAINS TO THE GREAT LAKES. AS FOR TEMPS...
COOLEST WEATHER WILL OCCUR EARLY IN THE WEEK BEHIND SHORTWAVE
PASSING SUN NIGHT/MON. THEN...DESPITE NW FLOW...TEMPS THRU THE
MIDWEEK PERIOD SHOULD BE CLOSE TO NORMAL OR EVEN A LITTLE ABOVE
NORMAL SINCE ERN TROF WILL NOT HAVE SIGNIFICANT AMPLITUDE INTO THE
ERN CONUS...RESULTING IN COOLER AIR STAYING E AND NE OF THE AREA.
TEMPS LATE WEEK WILL BE ABOVE NORMAL WITH WARMER/MORE HUMID
CONDITIONS.
BEGINNING SUN NIGHT/MON...CURRENTLY WELL-DEFINED MID-LEVEL LOW OVER
SASKATCHEWAN WILL BE WEAKENING CONSIDERABLY/OPENING UP AS IT GETS
SHEARED ESE IN THE FLOW BTWN RIDGE OVER THE ROCKIES AND AMPLIFYING
ERN CANADA TROF. DESPITE THE CURRENT VIGOROUS APPEARANCE/RELATIVELY
LARGE CIRCULATION OF MID-LEVEL LOW...RECENT MODEL TRENDS POINT
TOWARD A WEAKER REMNANT DROPPING THRU THE UPPER MISSISSIPPI
VALLEY/WRN GREAT LAKES WITH BULK OF DEEP LAYER FORCING PER QVECTORS
PASSING BY TO THE SW AND S OF UPPER MI SUN NIGHT/MON. AS SUCH...WILL
ONLY CONTINUE CHC POPS FOR SHRA/TSRA SUN NIGHT INTO MON MORNING.
WITH SHORTWAVE SWINGING BY TO THE S OF UPPER MI MON AND WITH
VIGOROUS LOW/MID LEVEL DRYING SURGING INTO THE AREA FROM THE N IN
THE WAKE OF SHORTWAVE ROTATING THRU NRN ONTARIO...EXPECT ANY SHRA TO
END FROM NW TO SE DURING THE DAY WITH CLEARING FOLLOWING. IT WILL BE
A COOLER DAY...ESPECIALLY NEAR LAKE SUPERIOR...DUE TO BREEZY N WINDS
AND CLOUDS DOMINATING INTO AT LEAST EARLY AFTN. A CHILLY NIGHT IS
THEN ON THE WAY FOR MON NIGHT AS HIGH PRES BUILDS INTO THE UPPER
LAKES. WITH VERY DRY COLUMN (PRECIPITABLE WATER 30-50PCT OF NORMAL)
AND WINDS DIMINISHING TO LIGHT/CALM...WILL CONTINUE OUR RECENT TREND
OF LOWERING MIN TEMPS FOR MON NIGHT. WILL FAVOR LOWER END OF MODEL
GUIDANCE...ESPECIALLY OVER THE W WHERE SFC HIGH PRES CENTER WILL BE
ARRIVING DURING THE NIGHT. WITH IDEAL RADIATIONAL COOLING
CONDITIONS...FROST IS CERTAINLY POSSIBLE IN THE USUAL COLDER
AREAS...AND A MENTION OF FROST WILL BE INCLUDED IN FCST. SOME OF THE
TRADITIONAL COLD SPOTS COULD FALL TO NEAR FREEZING. RECORD LOW FOR
NWS MQT SITE ON THE 18TH IS 38F. NOT OUT OF THE QUESTION THAT RECORD
COULD BE TIED OR POSSIBLY BROKEN.
IN THE WAKE OF THE SHORTWAVE PASSAGE MON...SFC HIGH PRES WILL SETTLE
INTO THE UPPER LAKES TUE...PROVIDING A DRY/PLEASANT MID JUNE DAY
WITH ABUNDANT SUNSHINE UNDER LINGERING VERY DRY COLUMN. LAKE BREEZES
WILL BE THE RULE...KEEPING LAKESIDE LOCATIONS COOLER IN THE AFTN.
UTILIZING MIXING HEIGHTS TO DETERMINE POSSIBLE DWPT CRASH IN THE
AFTN SUGGESTS DWPTS COULD DROP INTO THE 20S IN THE INTERIOR...BUT
DID NOT GO THAT LOW JUST YET. EVEN WITH MID 30S DWPTS...RH WILL
BOTTOM OUT AROUND 25PCT. FORTUNATELY...LIGHT WINDS WILL KEEP FIRE WX
CONCERNS IN CHECK. MEDIUM RANGE GUIDANCE HAS AND CONTINUES TO HINT
THAT A SHORTWAVE MAY DROP SE...PASSING JUST N OF UPPER MI WED/WED
NIGHT. GIVEN THE FAIRLY CONSISTENT SIGNAL FROM ALL MEDIUM RANGE
GUIDANCE...IT APPEARS THERE MAY BE SOME PCPN AT SOME POINT LATER
WED/WED NIGHT. NOTHING MORE THAN SCHC POPS ARE WARRANTED AT THIS
TIME GIVEN THE UNCERTAINTY AND WHAT SHOULD BE LOW COVERAGE IF PCPN
DOES OCCUR. IF WAVE IS FASTER AND ARRIVES DURING PEAK HEATING WED...
PCPN CHC WILL BE GREATER...BUT WOULD STILL NOT EXPECT ANYTHING MORE
THAN SCT COVERAGE.
IT WOULD APPEAR THU SHOULD BE DRY. HOWEVER...THERE IS THE POTENTIAL
FOR SUBTLE BOUNDARY ASSOCIATED WITH SHORTWAVE PASSING BY THE AREA WED
NIGHT TO HANG UP OVER/NEAR UPPER MI...AND THAT COULD BE THE FOCUS FOR
SOME CONVECTION THU AFTN. SCHC/LOW CHC POPS WERE INCLUDED IN FCST.
AS MENTIONED EARLIER...THE LATE WEEK PERIOD COULD BECOME ACTIVE AS
SHORTWAVES TRACK ACROSS THE NRN CONUS TO THE GREAT LAKES...
SUPPRESSING THE RIDGE THAT WAS SHIFTING ACROSS THE PLAINS TO THE
MISSISSIPPI VALLEY. SIGNAL LOOKS STRONG ENOUGH TO WARRANT AT LEAST
MID RANGE CHC POPS FOR SHRA/TSRA FOR MUCH OF FRI AND SAT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 133 AM EDT SUN JUN 16 2013
FOG AND LOW CLOUDS WILL MAKE THE FCST A CHALLENGE THIS MORNING. TEMPO
IFR VIS WILL OCCUR OVERNIGHT AT IWD AND SAW WITH FOG AND THEN VFR
CONDITIONS ARE EXPECTED THROUGH THE REST OF THE PERIOD WITH MIXING
TAKING PLACE DURING THE DAY. AT CMX EXPECT LIFR TO VLIFR VSBY IN FOG
AS IT ADVECTS IN OFF THE LAKE. THIS SHOULD MIX OUT BY MORNING WITH
VFR CONDITIONS EXPECTED THEN THROUGH REST OF PERIOD AT CMX. &&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 432 PM EDT SAT JUN 15 2013
EXPECT WINDS LESS THAN 20KT ACROSS LAKE SUPERIOR THRU THE FCST
PERIOD AS PRES GRADIENT WILL REMAIN GENERALLY WEAK...TYPICAL OF THE
WARM SEASON. THERE MAY BE SOME FOG PATCHES THRU SUN EVENING BEFORE
DRIER AIR BEGINS TO SURGE S INTO THE AREA. IF SOME RAINFALL OCCURS
OVER THE LAKE...FOG WILL BE MORE LIKELY TO FORM AND BECOME MORE
WIDESPREAD/DENSE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...ROLFSON
AVIATION...07/JV
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1152 PM EDT SAT JUN 15 2013
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 345 PM EDT SAT JUN 15 2013
A LOW PRESSURE SYSTEM WILL MOVE THROUGH THE GREAT LAKES REGION
TONIGHT BRINGING SHOWERS AND THUNDERSTORMS. SEVERE WEATHER IS NOT
EXPECTED. THE RAIN WILL COME TO AN END ON SUNDAY FROM NORTH TO
SOUTH. ANOTHER LOW WILL MOVE THROUGH THE AREA ON MONDAY BRINGING
ADDITIONAL SHOWERS AND STORMS TO THE AREA. CONDITIONS WILL DRY OUT
MONDAY NIGHT AS HIGH PRESSURE SETTLES INTO THE REGION. DRY WEATHER
IS THEN FORECAST FROM MONDAY NIGHT THROUGH THURSDAY AS THE HIGH ONLY
SLOWLY MOVES THROUGH. HIGHS WILL TOP OUT AROUND 80 DEGREES SUNDAY
AND MONDAY....FALLING BACK INTO THE 70S FOR TUESDAY THROUGH THURSDAY.
&&
.UPDATE...
ISSUED AT 755 PM EDT SAT JUN 15 2013
WE HAVE ISSUED AN UPDATE THIS EVENING TO FRESHEN UP THE FCST A
BIT. WE ARE CURRENTLY IN A LULL BETWEEN THE WAVE THAT MOVED
THROUGH THE SRN PORTION OF THE FCST AREA EARLIER...AND THE
CONVECTION THAT IS STILL EXPECTED OVERNIGHT. THE LATEST HRRR RUC
HAS A PRETTY GOOD HANDLE ON THE CURRENT SITUATION. IT THEN FILLS
IN SHOWERS AND STORMS OVER A GOOD PORTION OF WISCONSIN THIS
EVENING...WITH IT ALL MOVING IN ACROSS LOWER MICHIGAN AFTER 05Z OR
SO.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 345 PM EDT SAT JUN 15 2013
MAIN FORECAST ISSUE WAS DETERMINING CHANCES FOR PRECIPITATION AS A
COUPLE OF WEAK LOW PRESSURE SYSTEMS MOVE THROUGH THE REGION.
AS FOR TONIGHT...SOME QUESTION AS TO HOW WIDESPREAD THE
PRECIPITATION IS GOING TO BE...BUT FELT LIKELY CHANCES (60/70 PCT)
FOR SHOWERS AND STORMS WERE STILL WARRANTED. THE 850MB LLJ INCREASES
OVERNIGHT...WITH WIND CONVERGENCE LOCATED RIGHT OVER THE CWA.
MOISTURE TRANSPORT CONTINUES AT 850MB/S TONIGHT...ALBEIT OF LIGHT TO
MODERATE VALUES. FEEL THE HEAVIER RAINS WILL FALL ACROSS THE
SOUTHERN HALF OF THE FORECAST AREA. A WEAK COLD FRONT MAY HELP TO
FOCUS PRECIPITATION AS WELL...ALTHOUGH CONVERGENCE IS NOT
IMPRESSIVE. UPSTREAM VORT OVER MINNESOTA AND IOWA WILL LIKELY BE THE
MAIN FORCING MECHANISM. WEAK INSTABILITY SHOULD BE ENOUGH FOR SOME
EMBEDDED STORMS.
THE PRECIPITATION WILL LINGER INTO SUNDAY ESPECIALLY IN THE SOUTH
AND SOUTHEAST. BY EARLY TO MID AFTERNOON THE FINAL VESTIGES OF
PRECIPITATION SHOULD BE EXITING THE SOUTHEAST CWA TOWARDS JACKSON. A
DRYING WEST AND NORTHWEST WIND SHOULD TAKE SKIES MOSTLY SUNNY.
SUNDAY NIGHT CONTINUED THE DRY FORECAST DESPITE A WEAK FRONT NUDGING
DOWN FROM THE NORTH ACROSS NORTHERN LOWER MICHIGAN. FEEL
PRECIPITATION WITH THIS FRONT WILL HOLD OFF UNTIL MONDAY. SCATTERED
SHOWERS AND STORMS EXPECTED WITH THIS FRONT MONDAY INTO MONDAY
EVENING. CONDITIONS DRY OUT MONDAY NIGHT WITH HIGH PRESSURE BUILDING
IN.
.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 345 PM EDT SAT JUN 15 2013
A COOLER TREND WAS NOTED ON THE MEDIUM RANGE MODELS AS THE MONDAY
NIGHT SHORT WAVE CONTINUES TO DEEPEN AS IT HEADS TOWARD NEW
ENGLAND. THIS WILL HELP DRAG DOWN COOL CANADIAN AIR FROM THE
CENTRAL CONTINENT. H8 TEMPS DIP TO AROUND 8C SO LOWERED TEMPS FOR
TUESDAY THROUGH WEDNESDAY...WITH HIGHS MAINLY 70 TO 75 EACH DAY AND
TUESDAY NIGHT LOWS WERE DROPPED TO 45 TO 50. A SIGNIFICANT WARM UP
IS EXPECTED INTO THURSDAY AND EVEN WARMER ON FRI/SAT AS H8 TEMPS ARE
PROGGED TO INCREASE TO AROUND 18C...BRINGING MAX TEMPS TO 80 TO 85
FOR FRI/SAT.
THE COOLISH MID WEEK WILL BE CURIOSITY OF CANADIAN HIGH PRESSURE
THAT SHOULD BE MOVING OVER THE CWA BY WED. SOUTHERLY WINDS BEHIND
THE HIGH WILL RESULT IN THE WARMING TREND LATER IN THE WEEK. DRY
WEATHER IS EXPECTED THROUGH THURSDAY NIGHT. THEN BY FRI/SAT
INCREASING GULF MOISTURE AND A COUPLE OF WEAK SHORT WAVES SHOULD
CREATE THE CHANCE OF SHOWERS AND STORMS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1152 PM EDT SAT JUN 15 2013
SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS LOWER MICHIGAN
OVERNIGHT BRINGING MVFR CONDITIONS AND BRIEF HEAVY RAIN AND
ISOLATED AREAS OF GUSTY WINDS AND SMALL HAIL. THE RAIN SHOULD BE
OVER BY 12Z WITH VFR CONDITIONS EXPECTED FOR SUNDAY.
&&
.MARINE...
ISSUED AT 345 PM EDT SAT JUN 15 2013
WINDS AND WAVES ARE EXPECTED TO REMAIN BELOW ADVISORY CRITERIA THE
NEXT COUPLE OF DAYS. SOUTHWEST WINDS TODAY AND AGAIN SUNDAY NIGHT OF
10 TO 20 KNOTS WILL LIKELY BUMP WAVES UP INTO THE 1 TO 3 FOOT
CATEGORY. MONDAY NIGHT NORTHERLY WINDS WILL ELEVATE WAVES ONCE AGAIN
BEHIND A LOW PRESSURE SYSTEM...BUT A NORTHERLY FLOW MAY KEEP THE
HIGHEST WAVES OFF SHORE.
&&
.HYDROLOGY...
ISSUED AT 345 PM EDT SAT JUN 15 2013
4 RIVER ADVISORIES REMAIN FROM WEDNESDAY NIGHT/S RAIN. USGS PERCENT
OF NORMAL MAP ILLUSTRATES WELL THE AREA THAT RECEIVED THE HEAVY
RAIN...ESSENTIALLY THE MIDDLE OF THE FORECAST AREA THROUGH PORTIONS
OF THE GRAND BASIN. AREAS TO THE NORTH AND SOUTH REMAIN NEAR NORMAL
FLOWS. RAINFALL THE NEXT COUPLE DAYS SHOULD RANGE FROM AROUND A
QUARTER OF AN INCH ACROSS THE NORTH TO POSSIBLY AS MUCH AS THREE
QUARTERS OF AN INCH IN THE SOUTH. THIS RAINFALL MAY BUMP A FEW
ADDITIONAL SITES BACK INTO ADVISORY CATEGORY THAT ARE JUST BELOW
CRITERIA.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...NJJ
SYNOPSIS...DUKE
SHORT TERM...DUKE
LONG TERM...JK
AVIATION...OSTUNO
HYDROLOGY...DUKE
MARINE...DUKE
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
755 PM EDT SAT JUN 15 2013
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 345 PM EDT SAT JUN 15 2013
A LOW PRESSURE SYSTEM WILL MOVE THROUGH THE GREAT LAKES REGION
TONIGHT BRINGING SHOWERS AND THUNDERSTORMS. SEVERE WEATHER IS NOT
EXPECTED. THE RAIN WILL COME TO AN END ON SUNDAY FROM NORTH TO
SOUTH. ANOTHER LOW WILL MOVE THROUGH THE AREA ON MONDAY BRINGING
ADDITIONAL SHOWERS AND STORMS TO THE AREA. CONDITIONS WILL DRY OUT
MONDAY NIGHT AS HIGH PRESSURE SETTLES INTO THE REGION. DRY WEATHER
IS THEN FORECAST FROM MONDAY NIGHT THROUGH THURSDAY AS THE HIGH ONLY
SLOWLY MOVES THROUGH. HIGHS WILL TOP OUT AROUND 80 DEGREES SUNDAY
AND MONDAY....FALLING BACK INTO THE 70S FOR TUESDAY THROUGH THURSDAY.
&&
.UPDATE...
ISSUED AT 755 PM EDT SAT JUN 15 2013
WE HAVE ISSUED AN UPDATE THIS EVENING TO FRESHEN UP THE FCST A
BIT. WE ARE CURRENTLY IN A LULL BETWEEN THE WAVE THAT MOVED
THROUGH THE SRN PORTION OF THE FCST AREA EARLIER...AND THE
CONVECTION THAT IS STILL EXPECTED OVERNIGHT. THE LATEST HRRR RUC
HAS A PRETTY GOOD HANDLE ON THE CURRENT SITUATION. IT THEN FILLS
IN SHOWERS AND STORMS OVER A GOOD PORTION OF WISCONSIN THIS
EVENING...WITH IT ALL MOVING IN ACROSS LOWER MICHIGAN AFTER 05Z OR
SO.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 345 PM EDT SAT JUN 15 2013
MAIN FORECAST ISSUE WAS DETERMINING CHANCES FOR PRECIPITATION AS A
COUPLE OF WEAK LOW PRESSURE SYSTEMS MOVE THROUGH THE REGION.
AS FOR TONIGHT...SOME QUESTION AS TO HOW WIDESPREAD THE
PRECIPITATION IS GOING TO BE...BUT FELT LIKELY CHANCES (60/70 PCT)
FOR SHOWERS AND STORMS WERE STILL WARRANTED. THE 850MB LLJ INCREASES
OVERNIGHT...WITH WIND CONVERGENCE LOCATED RIGHT OVER THE CWA.
MOISTURE TRANSPORT CONTINUES AT 850MB/S TONIGHT...ALBEIT OF LIGHT TO
MODERATE VALUES. FEEL THE HEAVIER RAINS WILL FALL ACROSS THE
SOUTHERN HALF OF THE FORECAST AREA. A WEAK COLD FRONT MAY HELP TO
FOCUS PRECIPITATION AS WELL...ALTHOUGH CONVERGENCE IS NOT
IMPRESSIVE. UPSTREAM VORT OVER MINNESOTA AND IOWA WILL LIKELY BE THE
MAIN FORCING MECHANISM. WEAK INSTABILITY SHOULD BE ENOUGH FOR SOME
EMBEDDED STORMS.
THE PRECIPITATION WILL LINGER INTO SUNDAY ESPECIALLY IN THE SOUTH
AND SOUTHEAST. BY EARLY TO MID AFTERNOON THE FINAL VESTIGES OF
PRECIPITATION SHOULD BE EXITING THE SOUTHEAST CWA TOWARDS JACKSON. A
DRYING WEST AND NORTHWEST WIND SHOULD TAKE SKIES MOSTLY SUNNY.
SUNDAY NIGHT CONTINUED THE DRY FORECAST DESPITE A WEAK FRONT NUDGING
DOWN FROM THE NORTH ACROSS NORTHERN LOWER MICHIGAN. FEEL
PRECIPITATION WITH THIS FRONT WILL HOLD OFF UNTIL MONDAY. SCATTERED
SHOWERS AND STORMS EXPECTED WITH THIS FRONT MONDAY INTO MONDAY
EVENING. CONDITIONS DRY OUT MONDAY NIGHT WITH HIGH PRESSURE BUILDING
IN.
.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 345 PM EDT SAT JUN 15 2013
A COOLER TREND WAS NOTED ON THE MEDIUM RANGE MODELS AS THE MONDAY
NIGHT SHORT WAVE CONTINUES TO DEEPEN AS IT HEADS TOWARD NEW
ENGLAND. THIS WILL HELP DRAG DOWN COOL CANADIAN AIR FROM THE
CENTRAL CONTINENT. H8 TEMPS DIP TO AROUND 8C SO LOWERED TEMPS FOR
TUESDAY THROUGH WEDNESDAY...WITH HIGHS MAINLY 70 TO 75 EACH DAY AND
TUESDAY NIGHT LOWS WERE DROPPED TO 45 TO 50. A SIGNIFICANT WARM UP
IS EXPECTED INTO THURSDAY AND EVEN WARMER ON FRI/SAT AS H8 TEMPS ARE
PROGGED TO INCREASE TO AROUND 18C...BRINGING MAX TEMPS TO 80 TO 85
FOR FRI/SAT.
THE COOLISH MID WEEK WILL BE CURIOSITY OF CANADIAN HIGH PRESSURE
THAT SHOULD BE MOVING OVER THE CWA BY WED. SOUTHERLY WINDS BEHIND
THE HIGH WILL RESULT IN THE WARMING TREND LATER IN THE WEEK. DRY
WEATHER IS EXPECTED THROUGH THURSDAY NIGHT. THEN BY FRI/SAT
INCREASING GULF MOISTURE AND A COUPLE OF WEAK SHORT WAVES SHOULD
CREATE THE CHANCE OF SHOWERS AND STORMS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 741 PM EDT SAT JUN 15 2013
VFR CONDITIONS THIS EVENING THEN SOME SHOWERS AND THUNDERSTORMS
AFTER MIDNIGHT WITH A FEW HOURS OF MVFR EXPECTED. CONDITIONS
SHOULD GO BACK TO VFR AFTER 12Z. WINDS WILL BE SOUTH THEN
SOUTHWEST AOB 10 KNOTS.
&&
.MARINE...
ISSUED AT 345 PM EDT SAT JUN 15 2013
WINDS AND WAVES ARE EXPECTED TO REMAIN BELOW ADVISORY CRITERIA THE
NEXT COUPLE OF DAYS. SOUTHWEST WINDS TODAY AND AGAIN SUNDAY NIGHT OF
10 TO 20 KNOTS WILL LIKELY BUMP WAVES UP INTO THE 1 TO 3 FOOT
CATEGORY. MONDAY NIGHT NORTHERLY WINDS WILL ELEVATE WAVES ONCE AGAIN
BEHIND A LOW PRESSURE SYSTEM...BUT A NORTHERLY FLOW MAY KEEP THE
HIGHEST WAVES OFF SHORE.
&&
.HYDROLOGY...
ISSUED AT 345 PM EDT SAT JUN 15 2013
4 RIVER ADVISORIES REMAIN FROM WEDNESDAY NIGHT/S RAIN. USGS PERCENT
OF NORMAL MAP ILLUSTRATES WELL THE AREA THAT RECEIVED THE HEAVY
RAIN...ESSENTIALLY THE MIDDLE OF THE FORECAST AREA THROUGH PORTIONS
OF THE GRAND BASIN. AREAS TO THE NORTH AND SOUTH REMAIN NEAR NORMAL
FLOWS. RAINFALL THE NEXT COUPLE DAYS SHOULD RANGE FROM AROUND A
QUARTER OF AN INCH ACROSS THE NORTH TO POSSIBLY AS MUCH AS THREE
QUARTERS OF AN INCH IN THE SOUTH. THIS RAINFALL MAY BUMP A FEW
ADDITIONAL SITES BACK INTO ADVISORY CATEGORY THAT ARE JUST BELOW
CRITERIA.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...NJJ
SYNOPSIS...DUKE
SHORT TERM...DUKE
LONG TERM...JK
AVIATION...OSTUNO
HYDROLOGY...DUKE
MARINE...DUKE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
722 PM EDT SAT JUN 15 2013
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 432 PM EDT SAT JUN 15 2013
WEAKENING UPPER RIDGE AXIS IS STILL OVER THE WESTERN GREAT
LAKES...WHILE A LARGE UPPER LOW IS SPINNING OVER CENTRAL
SASKATCHEWAN. THERE AREA A COUPLE SUBTLE DISTURBANCES ROUNDING THE
RIDGE. THE FIRST ONE IS CURRENTLY EXITING EASTERN UPPER MICHIGAN.
THIS WAVE COMBINED WITH BROAD WARM AIR ADVECTION TO PRODUCE
THE SHOWERS THIS MORNING OVER THE WEST AND THEN THE DIMINISHING
SHOWERS OVER THE EAST THIS AFTERNOON. THE NEXT WAVE IS CURRENTLY
ASSOCIATED WITH THE CONVECTION IN NORTHERN IOWA AND SOUTHERN
MINNESOTA AND MOVING TO THE EAST-NORTHEAST. AT THE SURFACE...A
TROUGH IS CURRENTLY STRETCHING SOUTH ACROSS EASTERN MINNESOTA FROM
THE LOW IN CENTRAL SASKATCHEWAN. POCKET OF MLCAPE VALUES AROUND
1000 J/KG IS LOCATED AHEAD OF THIS TROUGH IN WESTERN WISCONSIN AND
STARTING TO NOSE NORTHEAST INTO WESTERN UPPER MICHIGAN. SHOWERS AND
THUNDERSTORMS HAVE STARTED TO DEVELOP NORTH OF THE TWIN CITIES...AS
HINTED AT BY MORNING RUNS OF THE HRRR...AND HAVE BEEN LIFTING
NORTHEAST.
FOR THE REST OF THIS AFTERNOON AND TONIGHT THE FORECAST DEPENDS ON
TWO FEATURES...THE TROUGH MOVING THROUGH THE U.P. THIS EVENING AND
THE SHORTWAVE ASSOCIATED WITH THE DECAYING CONVECTION IN SOUTHEAST
MN. THEY BOTH SEEM TO BE INTERACTING OVER THE LAST COUPLE OF HOURS
WITH THE DEVELOPMENT OF THUNDERSTORMS NORTH OF THE TWIN CITIES AND
INTO WEST CENTRAL WISCONSIN. AS INDICATED BY THE HRRR THIS
MORNING...WOULD EXPECT THESE THUNDERSTORMS TO CONTINUE DEVELOP AND
PUSH NORTHEAST INITIALLY BEFORE THE STORM MOTIONS TAKE THEM MORE
EASTERLY AS IT ROUNDS THE RIDGE. ML CAPES SHOULD CONTINUE TO PUSH
NORTHEAST TOWARDS THE WISCONSIN BORDER...AS THE LOW CLOUDS BEGIN TO
THIN AND INCREASE HEATING. THE ONE CONCERN WILL BE THE THICKENING
HIGH CLOUDS ON THE NORTH SIDE OF THE CONVECTION MAY BE ENOUGH TO
LIMIT THE NORTHWARD EXTENT OF THE INSTABILITY. WITH THE SHORTWAVE
ALSO ROUNDING THE RIDGE...THAT SHOULD FOCUS THE BEST FORCING ACROSS
CENTRAL WISCONSIN. THEREFORE...WOULD EXPECT THE BEST CHANCE FOR
SHOWERS AND THUNDERSTORMS LATE THIS AFTERNOON AND EVENING OVER THE
SOUTHERN HALF OF THE CWA...ESPECIALLY NEAR THE WISCONSIN BORDER
WHERE THE BEST INSTABILITY WILL BE LOCATED AND STORM MOTION WOULD
TRACK THE THUNDERSTORMS. AT THIS POINT...WOULD EXPECT HEAVY RAIN TO
BE THE MAIN THREAT SINCE NCAPE SHOULD REMAIN BELOW 0.1 AND DCAPE
VALUES STRUGGLE TO RISE ABOVE 700 J/KG AS THE LOW CLOUDS OVER THE
SOUTHWEST DISSIPATE.
FARTHER NORTHWEST...THE UPPER LOW SPINNING IN CENTRAL SASKATCHEWAN
WILL LIKELY SPARK SOME SHOWERS AND THUNDERSTORMS ALONG THE
MN/ND/CANADA BORDER THIS AFTERNOON WHICH WILL TRACK EAST THIS
EVENING. WITH THE LOSS OF DIURNAL HEATING...WOULD EXPECT THEM TO
DIMINISH AS THEY APPROACH NORTHERN LAKE SUPERIOR. BUT WITH THE
CLOSE PROXIMITY OF THE UPPER LEVEL SHORTWAVES...DEEPER MOISTURE AND
STEEPER LAPSE RATES...WILL HOLD ONTO SLIGHT CHANCE POPS AS THAT
MOVES ACROSS THE NORTHERN LAKE TONIGHT.
OTHERWISE...ONCE THE THE TROUGH AND CONVECTION SLIDE THROUGH...DRY
MID LEVEL AIR WILL SURGE OVER THE AREA AND LEAD TO A FAIRLY QUIET
NIGHT WITH DECREASING CLOUDS FROM WEST TO EAST. WITH THE MOIST
SOUTHERLY FLOW OFF LAKE MICHIGAN AND THE POTENTIAL FOR SOME FOG OFF
THE LAKE WITH THE SHOWERS UPSTREAM...HAVE ADDED IN FOG OVER EASTERN
UPPER MICHIGAN. ALSO ADDED A MENTION OVER CENTRAL/EASTERN LAKE
SUPERIOR...ALONG WITH THE KEWEENAW...SINCE THERE IS A DENCENT
CONSISTENCY IN THE MODELS AND THERE ARE 50S AND LOW 60S DEWPOINTS
MOVING OVER WESTERN/CENTRAL LAKE SUPERIOR THIS AFTERNOON.
UNFORTUNATELY...CLOUDS HAVE OBSCURED THE LAKE TO SEE IF ANY FOG IS
GOING...BUT SHIP OBS HAVE YET TO REPORT FOG.
EXPECT SUNDAY TO START OFF ON THE NICE SIDE WITH A DECENT AMOUNT OF
SUNSHINE...AS THE AREA IS STILL UNDER THE 900-500MB DRY AIR. THIS
DRY AIR WILL SLIDE EAST-SOUTHEAST THROUGH THE DAY AS THE UPPER
LOW WEST OF LAKE WINNIPEG SHEARS OFF AND STARTS TO SEND PIECES OF
ENERGY ACROSS THE AREA. THE ABUNDANT SUNSHINE TO START THE DAY WILL
ALLOW TEMPERATURES TO QUICKLY RISE INTO THE 70S...WITH A FEW
VALUES IN THE LOWER 80S OVER THE SOUTH CENTRAL.
AS FOR FORCING FEATURES...SURFACE LOW ASSOCIATED WITH THE ELONGATED
TROUGH WILL BE RE-FOCUSING EAST OF LAKE SUPERIOR SUNDAY MORNING AND
THEN PUSHING EAST INTO SOUTHEASTERN ONTARIO ON SUNDAY AFTERNOON...AS
THE MAIN AREA OF SHORTWAVE ENERGY FOLLOWS THAT SAME TRACK. THIS WILL
LEAVE A SURFACE TROUGH OR COLD FRONT BACK ACROSS LAKE
SUPERIOR...WHICH WILL START TO DROP SOUTH OVER UPPER MICHIGAN DURING
THE AFTERNOON HOURS. AS THAT OCCURS...THE INCREASING 850-750MB
MOISTURE SHOULD SPARK SOME HIGH BASED DIURNAL CU. WITH MODEL
CONSENSUS ML CAPE VALUES AROUND 400J/KG...QUESTION COMES TO IF THERE
WILL BE ENOUGH MOISTURE FOR SHOWERS TO DEVELOP. MARGINAL MID-LEVEL
MOISTURE AND DECENT DRY AIR ABOVE 650MB WILL LIKELY
LIMIT THINGS...BUT DID INCLUDE SLIGHTS AND LOW END CHANCES FROM MID
AFTERNOON ON IN CASE THE DEEPER MOISTURE WITH THE TROUGH ARRIVES A
LITTLE QUICKER. IF THERE WASN/T THE INVERTED V LOOK TO THE
SOUNDINGS WITH THE MIXING TO 800-700MB WOULD HAVE CONSIDERED THE
HIGHER INSTABILITY VALUES SEEN IN THE NAM...ML CAPE VALUES AROUND
1000 J/KG...AND BOOSTED POPS UP MORE. EXPECT THE SEVERE THREAT TO BE
LIMITED WITH THESE SHOWERS/THUNDERSTORMS UNLESS THE NAM SOLUTION
VERIFIES. THIS IS DUE TO THE CAPE IS FAIRLY TALL/SKINNY WITH NCAPE
VALUES BELOW 0.1 ALTHOUGH EFFECTIVE SHEAR VALUES ARE IN THE 30-40KT
RANGE. GUSTY WINDS COULD BE A CONCERN WITH THAT INVERTED V
LOOK...DCAPE VALUES OVER 750 J/KG OVER THE SOUTH CENTRAL...AND
EXISTING WINDS GUSTING TO 20-25KTS OVER THE WESTERN CWA.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 432 PM EDT SAT JUN 15 2013
THE FIRST HALF OF THE UPCOMING WEEK WILL FEATURE NW FLOW INTO THE
UPPER GREAT LAKES BTWN A RIDGE DRIFTING FROM THE ROCKIES TO THE
PLAINS AND A BROAD TROF OVER ERN NAMERICA. LATER IN THE WEEK...RIDGE
PROGRESSING INTO THE PLAINS WILL BE SUPPRESSED BY SHORTWAVE ENERGY
EJECTING E FROM A TROF OVER THE PACIFIC NW. WHILE THERE MAY BE SOME
LIMITED OPPORTUNITIES FOR PCPN...NW FLOW WILL NOT SUPPORT
WIDESPREAD/SIGNIFICANT RAINFALL THRU MID WEEK. THE LATE WEEK PERIOD
COULD THEN BECOME ACTIVE WITH BETTER PCPN PROSPECTS AS SHORTWAVES
EJECT E ACROSS THE NRN PLAINS TO THE GREAT LAKES. AS FOR TEMPS...
COOLEST WEATHER WILL OCCUR EARLY IN THE WEEK BEHIND SHORTWAVE
PASSING SUN NIGHT/MON. THEN...DESPITE NW FLOW...TEMPS THRU THE
MIDWEEK PERIOD SHOULD BE CLOSE TO NORMAL OR EVEN A LITTLE ABOVE
NORMAL SINCE ERN TROF WILL NOT HAVE SIGNIFICANT AMPLITUDE INTO THE
ERN CONUS...RESULTING IN COOLER AIR STAYING E AND NE OF THE AREA.
TEMPS LATE WEEK WILL BE ABOVE NORMAL WITH WARMER/MORE HUMID
CONDITIONS.
BEGINNING SUN NIGHT/MON...CURRENTLY WELL-DEFINED MID-LEVEL LOW OVER
SASKATCHEWAN WILL BE WEAKENING CONSIDERABLY/OPENING UP AS IT GETS
SHEARED ESE IN THE FLOW BTWN RIDGE OVER THE ROCKIES AND AMPLIFYING
ERN CANADA TROF. DESPITE THE CURRENT VIGOROUS APPEARANCE/RELATIVELY
LARGE CIRCULATION OF MID-LEVEL LOW...RECENT MODEL TRENDS POINT
TOWARD A WEAKER REMNANT DROPPING THRU THE UPPER MISSISSIPPI
VALLEY/WRN GREAT LAKES WITH BULK OF DEEP LAYER FORCING PER QVECTORS
PASSING BY TO THE SW AND S OF UPPER MI SUN NIGHT/MON. AS SUCH...WILL
ONLY CONTINUE CHC POPS FOR SHRA/TSRA SUN NIGHT INTO MON MORNING.
WITH SHORTWAVE SWINGING BY TO THE S OF UPPER MI MON AND WITH
VIGOROUS LOW/MID LEVEL DRYING SURGING INTO THE AREA FROM THE N IN
THE WAKE OF SHORTWAVE ROTATING THRU NRN ONTARIO...EXPECT ANY SHRA TO
END FROM NW TO SE DURING THE DAY WITH CLEARING FOLLOWING. IT WILL BE
A COOLER DAY...ESPECIALLY NEAR LAKE SUPERIOR...DUE TO BREEZY N WINDS
AND CLOUDS DOMINATING INTO AT LEAST EARLY AFTN. A CHILLY NIGHT IS
THEN ON THE WAY FOR MON NIGHT AS HIGH PRES BUILDS INTO THE UPPER
LAKES. WITH VERY DRY COLUMN (PRECIPITABLE WATER 30-50PCT OF NORMAL)
AND WINDS DIMINISHING TO LIGHT/CALM...WILL CONTINUE OUR RECENT TREND
OF LOWERING MIN TEMPS FOR MON NIGHT. WILL FAVOR LOWER END OF MODEL
GUIDANCE...ESPECIALLY OVER THE W WHERE SFC HIGH PRES CENTER WILL BE
ARRIVING DURING THE NIGHT. WITH IDEAL RADIATIONAL COOLING
CONDITIONS...FROST IS CERTAINLY POSSIBLE IN THE USUAL COLDER
AREAS...AND A MENTION OF FROST WILL BE INCLUDED IN FCST. SOME OF THE
TRADITIONAL COLD SPOTS COULD FALL TO NEAR FREEZING. RECORD LOW FOR
NWS MQT SITE ON THE 18TH IS 38F. NOT OUT OF THE QUESTION THAT RECORD
COULD BE TIED OR POSSIBLY BROKEN.
IN THE WAKE OF THE SHORTWAVE PASSAGE MON...SFC HIGH PRES WILL SETTLE
INTO THE UPPER LAKES TUE...PROVIDING A DRY/PLEASANT MID JUNE DAY
WITH ABUNDANT SUNSHINE UNDER LINGERING VERY DRY COLUMN. LAKE BREEZES
WILL BE THE RULE...KEEPING LAKESIDE LOCATIONS COOLER IN THE AFTN.
UTILIZING MIXING HEIGHTS TO DETERMINE POSSIBLE DWPT CRASH IN THE
AFTN SUGGESTS DWPTS COULD DROP INTO THE 20S IN THE INTERIOR...BUT
DID NOT GO THAT LOW JUST YET. EVEN WITH MID 30S DWPTS...RH WILL
BOTTOM OUT AROUND 25PCT. FORTUNATELY...LIGHT WINDS WILL KEEP FIRE WX
CONCERNS IN CHECK. MEDIUM RANGE GUIDANCE HAS AND CONTINUES TO HINT
THAT A SHORTWAVE MAY DROP SE...PASSING JUST N OF UPPER MI WED/WED
NIGHT. GIVEN THE FAIRLY CONSISTENT SIGNAL FROM ALL MEDIUM RANGE
GUIDANCE...IT APPEARS THERE MAY BE SOME PCPN AT SOME POINT LATER
WED/WED NIGHT. NOTHING MORE THAN SCHC POPS ARE WARRANTED AT THIS
TIME GIVEN THE UNCERTAINTY AND WHAT SHOULD BE LOW COVERAGE IF PCPN
DOES OCCUR. IF WAVE IS FASTER AND ARRIVES DURING PEAK HEATING WED...
PCPN CHC WILL BE GREATER...BUT WOULD STILL NOT EXPECT ANYTHING MORE
THAN SCT COVERAGE.
IT WOULD APPEAR THU SHOULD BE DRY. HOWEVER...THERE IS THE POTENTIAL
FOR SUBTLE BOUNDARY ASSOCIATED WITH SHORTWAVE PASSING BY THE AREA WED
NIGHT TO HANG UP OVER/NEAR UPPER MI...AND THAT COULD BE THE FOCUS FOR
SOME CONVECTION THU AFTN. SCHC/LOW CHC POPS WERE INCLUDED IN FCST.
AS MENTIONED EARLIER...THE LATE WEEK PERIOD COULD BECOME ACTIVE AS
SHORTWAVES TRACK ACROSS THE NRN CONUS TO THE GREAT LAKES...
SUPPRESSING THE RIDGE THAT WAS SHIFTING ACROSS THE PLAINS TO THE
MISSISSIPPI VALLEY. SIGNAL LOOKS STRONG ENOUGH TO WARRANT AT LEAST
MID RANGE CHC POPS FOR SHRA/TSRA FOR MUCH OF FRI AND SAT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 722 PM EDT SAT JUN 15 2013
CONFIDENCE IS LOW IN THIS FORECAST AS CONVECTION NOT HANDLED WELL BY
MODELS AND THIS WILL AFFECT LOW CLOUDS. MVFR CIGS AT IWD AND SAW
SHOULD CLEAR OUT BY MID EVENING AND THEN VFR CONDITIONS EXPECTED
THROUGH THE REST OF THE PERIOD. CMX IS ANOTHER STORY WITH IFR CIGS
ALREADY IN THERE AND THINK WITH FOG ON THE LAKE...CANNOT SEE WHY
LIFR CONDITIONS WOULD NOT DEVELOP TONIGHT. THIS SHOULD MIX OUT BY
MORNING WITH VFR CONDITIONS EXPECTED THEN THROUGH REST OF PERIOD AT
CMX.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 432 PM EDT SAT JUN 15 2013
EXPECT WINDS LESS THAN 20KT ACROSS LAKE SUPERIOR THRU THE FCST
PERIOD AS PRES GRADIENT WILL REMAIN GENERALLY WEAK...TYPICAL OF THE
WARM SEASON. THERE MAY BE SOME FOG PATCHES THRU SUN EVENING BEFORE
DRIER AIR BEGINS TO SURGE S INTO THE AREA. IF SOME RAINFALL OCCURS
OVER THE LAKE...FOG WILL BE MORE LIKELY TO FORM AND BECOME MORE
WIDESPREAD/DENSE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...ROLFSON
AVIATION...07
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS HASTINGS NE
132 AM CDT SUN JUN 16 2013
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 306 PM CDT SAT JUN 15 2013
TONIGHT THROUGH SUNDAY AFTERNOON. PRIMARY CONCERN WILL CENTER
AROUND THUNDERSTORM CHANCES. WILL NOT MAKE THIS TOO DETAILED TODAY
JUST IN CASE CONVECTION GETS GOING BY MID AFTERNOON.
CURRENT WATER VAPOR IMAGERY AND UPPER AIR DATA SHOWING CLOSED
UPPER LOW OVER SASKATCHEWAN CANADA WITH BROAD TROUGH INTO THE
NORTHERN PLAINS. THIS FEATURE GIVING THE NORTHERN PART OF OUR CWA
A LITTLE STRONGER DEEP LAYER SHEAR THAN THE SOUTHERN PART DUE TO
THE STRONGER WESTERLY FLOW. ANOTHER WEAK WAVE FROM KS TO TX HAS
HELPED DEVELOP/SUSTAIN NON SEVERE CONVECTION OVER THE SOUTHERN AND
SOUTHEAST PART OF THE CWA THIS MORNING...AND WAS JUST PUSHING TO
THE EAST OF THE AREA BY 1 PM CDT. ALSO ON THE VISIBLE SATELLITE
IMAGERY...LOOKS LIKE AN MCV OR NEDDY EDDY SWIRLING FROM THE SOUTH
CENTRAL INTO THE EASTERN PART OF THE CWA EARLY THIS AFTERNOON BUT
WOULD EXPECT ANY EFFECTS FROM THIS TO BE TO OUR EAST. DIFFICULT TO
PLACE THE SURFACE BOUNDARY EARLY THIS AFTERNOON DUE TO DIFFUSE
NATURE OF THE BOUNDARY AND EXTENSIVE CLOUD COVER THAT PASSED
ACROSS OUR SOUTHERN CWA THIS MORNING. BY 17Z THE BOUNDARY APPEARED
TO BE LYING FROM THE SOUTHWEST TO THE NORTHEAST PART OF THE CWA.
BEST SURFACE MOISTURE POOLING IN THIS AREA WITH UPPER 60S FOR
DEWPOINTS...AS COMPARED TO THE 50S NORTHWEST OF THE CWA. TO GO
ALONG WITH THIS...ML CAPES THE HIGHEST HERE AT 17Z WITH VALUES
AROUND 1500 J/KG. 0-6 KM SHEAR AT 50 KT ALONG NEB/SDAK BORDER...30
KT IN THE NORTHERN PART OF THE CWA AND LESS THAN THAT IN OUR
SOUTH.
FIRST QUESTION THEN IS WILL THUNDERSTORMS POP THIS AFTERNOON AND
TO WHAT EXTENT. THE 4KM WRF DEVELOPS CONVECTION ALONG THE FRONT
LATE THIS AFTERNOON AND THEN SAGS IT SOUTH DURING THE EVENING. IT
ALSO DEVELOPS AN MCS OVER NORTHEAST COLORADO THIS EVENING AND THEN
SLIDES IT EAST ACROSS NORTHERN KS OVERNIGHT. THIS SCENARIO ALSO
SUPPORTED BY SEVERAL RUNS OF THE HRRR TODAY. QUESTION HERE IS WILL
THE TRACK TAKE IT ACROSS OR JUST SOUTH OF OUR KS COUNTIES. WILL
MOST LIKELY KEEP AT LEAST A SLIGHT CHANCE IN THE NORTH LATER TODAY
INTO THE EVENING WITH A LITTLE BIT BETTER CHANCES ACROSS KS. SO
FAR SEVERE CHANCES LATER THIS AFTERNOON DO NOT LOOK THAT PROMISING
DUE TO THE LACK OF MID LEVEL FORCING AND WEAK SHEAR. COULD SEE
SOME SEVERE THUNDERSTORMS OVERNIGHT IF MCS SCENARIO MATERIALIZES.
THE SITUATION IS NOT MUCH CLEARER FOR SUNDAY WITH LOCATIONS OF THE
SURFACE BOUNDARIES STILL A BIT OF A QUESTION. IT DOES LOOK LIKE WE
COULD HAVE SOME MID LEVEL SUPPORT AND INSTABILITY AND SHEAR
PARAMETERS LOOKING MORE FAVORABLE THAN THEY DO TODAY. LATEST DAY 2
OUTLOOK FROM SPC HAS AREA IN A SLIGHT RISK. THEY MENTION THAT
CONDITIONS LOOK FAVORABLE FOR A LINEAR SYSTEM TO DEVELOP WITH
DAMAGING WINDS THE GREATEST THREAT ALTHOUGH EARLY ON WE COULD SEE
DISCRETE CELLS WITH LARGE HAIL...DAMAGING WINDS AND A FEW
TORNADOES POSSIBLE. WILL PROBABLY HAVE HIGHEST POPS IN THE SOUTH
FOR SUNDAY...CLOSER TO EXPECTED LOCATION OF THE SURFACE BOUNDARY.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 306 PM CDT SAT JUN 15 2013
GUIDANCE FROM THE NAM...OPERATIONAL GFS...EC...AND SREF-MEAN
SUGGESTS A MID TO UPPER LEVEL RIDGE WILL LINGER OVER THE ROCKY
MOUNTAIN RANGE MONDAY AND TUESDAY...THUS HELPING PROMOTE
NORTHWESTERLY MID TO UPPER LEVEL FLOW OVER THE CENTRAL PLAINS.
PERIODIC MID LEVEL PERTURBATIONS ARE EXPECTED TO PUSH OVER OUR
AREA WITHIN THE MEAN MID LEVEL FLOW...THUS PRESENTING PERIODS OF
INCREASED OMEGA. SUNDAY NIGHT INTO EARLY MONDAY MORNING IS ONE
SUCH TIME PERIOD WITH QPF FIELDS FROM THE OPERATIONAL GFS...EC
...SREF-MEAN...AND TO A LESSER EXTENT THE NAM...ALL SUGGESTING
MEASURABLE PRECIPITATION WILL BE REALIZED OVER OUR AREA.
MAINTAINED THE ~50% POPS INHERITED FROM THE PREVIOUS FORECAST FOR
SUNDAY NIGHT INTO EARLY MONDAY MORNING AS A RESULT. MONDAY INTO
TUESDAY...POP-RELATED DETAILS BECOME MURKY AT BEST...WITH VARIOUS
MODELS SUGGESTING THE AFOREMENTIONED MID LEVEL PERTURBATIONS WILL
MOVE OVER SOME PORTION OF OUR CWA AT SOME POINT IN TIME. RESULTANT
QPF FIELDS ARE ALL OVER THE PLACE AS A RESULT...THUS MAKING IT
DIFFICULT TO PIN DOWN AN EXACT LOCATION TO PLACE POPS. THAT BEING
SAID...THERE DOES SEEM TO BE SOME AGREEMENT BETWEEN THE
NAM...EC...AND SREF-MEAN OF MEASURABLE PRECIPITATION BEING
REALIZED SOMEWHERE ACROSS OUR WEST/SOUTHWESTERN CWA BOTH MONDAY
AND TUESDAY DURING THE AFTERNOON AND EVENING HOURS. FORECAST
PROXIMITY SOUNDINGS FROM ACROSS OUR WEST/SOUTHWEST...PER THE
NAM...EC...AND EVEN THE OPERATIONAL GFS DESPITE ITS DRY QPF OUTPUT
ON BOTH DAYS...SUGGEST STEEP LOW TO MID LEVEL LAPSE RATES MAY
ALLOW A FEW LOCATIONS TO AUTO-CONVECT ACROSS THE HIGHER TERRAIN OF
OUR WEST/SOUTHWESTERN CWA. GIVEN THE MODEST CONSENSUS FROM MODEL
QPF FIELDS...AS WELL AS THE LOW TO MID LEVEL LAPSE RATES SUGGESTED
BY THE AFOREMENTIONED FORECAST PROXIMITY SOUNDINGS...WENT AHEAD
WITH ~20% POPS ACROSS ROUGHLY THE WEST/SOUTHWESTERN ONE-THIRD OF
OUR CWA FOR THE AFTERNOON AND EVENING HOURS ON MONDAY AND TUESDAY.
WEDNESDAY AND BEYOND...THE OPERATIONAL GFS AND EC BOTH SUGGEST MID
TO UPPER LEVEL FLOW WILL TRANSITION FROM THE NORTHWEST TO MORE OF
A SOUTHWESTERLY DIRECTION...WITH MULTIPLE MID LEVEL PERTURBATIONS
MOVING OVER THE REGION. ALLBLEND RESPONDED BY PROVIDING 20-50%
POPS FOR VARIOUS POINTS ACROSS OUR CWA DURING VARIOUS TIME
PERIODS. TIMING AND POSITION DETAILS WITH RESPECT TO ANY OF THE
MID LEVEL PERTURBATIONS MID TO LATE NEXT WEEK WILL LIKELY NOT
BECOME ANY MORE CLEAR FOR A COUPLE MORE DAYS AND AS A RESULT...THE
PROBABILITY OF SUCCESSFULLY IMPROVING THE FORECAST AS PROVIDED BY
ALLBLEND IS LOW. GIVEN THIS LOW PROBABILITY...OPTED TO LEAVE THE
ALLBLEND POPS UNCHANGED FOR THE MOST PART.
FORECAST PROXIMITY SOUNDINGS FROM ACROSS OUR CWA...IN PARTICULAR
THE NAM...SUGGEST ASCENDING PARCELS ROOTED TO BETWEEN 825MB AND
750MB WILL HAVE ~1500J/KG TO WORK WITH SUNDAY NIGHT INTO EARLY
MONDAY MORNING. IN ADDITION TO THIS POTENTIAL ENERGY...DEEP LAYER
BULK SHEAR VALUES OF ~30KTS ARE ALSO FORECAST ACROSS MUCH OF OUR
AREA. ALTHOUGH CONFIDENCE IS NOT OVERLY HIGH WITH RESPECT TO
SEVERE WEATHER CHANCES SUNDAY NIGHT INTO EARLY MONDAY
MORNING...WILL GO AHEAD AND MAINTAIN SEVERE WEATHER WORDING IN THE
HWO FOR SUNDAY NIGHT AND EARLY MONDAY MORNING. SEVERE WEATHER
COULD BE OBSERVED SHOULD THUNDERSTORM ACTIVITY BE REALIZED ACROSS
OUR WEST/SOUTHWESTERN CWA DURING THE AFTERNOON AND/OR EVENING
HOURS MONDAY AND TUESDAY...WITH THE NAM...OPERATIONAL GFS...AND EC
ALL SUGGESTING DEEP LAYER MUCAPE VALUES GENERALLY IN THE
2000-3000J/KG RANGE. DEEP LAYER BULK SHEAR VALUES ON THE ORDER OF
~30KTS ARE ALSO FORECAST. GIVEN ALL THIS...WILL GO AHEAD AND
OUTLOOK THE THREAT FOR ISOLATED SEVERE WEATHER BOTH MONDAY AND
TUESDAY ACROSS OUR WEST/SOUTHWEST. MUCH LIKE THE OVERALL POP
FORECAST...DETAILS REGARDING SEVERE WEATHER TIMING AND POSITION
WEDNESDAY AND BEYOND WILL NOT LIKELY BECOME ANY MORE CLEAR FOR A
COUPLE MORE DAYS AND AS A RESULT...WILL CONTINUE THE GENERAL
THUNDERSTORM MENTION IN THE HWO FOR THE TIME BEING.
LITTLE CHANGE IN THE LOW LEVEL AIRMASS SHOULD PRESENT SIMILAR
TEMPERATURES BETWEEN MONDAY AND WEDNESDAY...WITH AFTERNOON HIGH
TEMPERATURE GENERALLY IN THE 80S CURRENTLY FORECAST. LOW LEVEL
SOUTHERLY FLOW AND RESULTANT LOW LEVEL WARM AIR ADVECTION
BEGINNING WEDNESDAY HOWEVER...SHOULD PROMOTE A WARMING TREND TO
FINISH OUT THE FORECAST PERIOD...WITH AFTERNOON HIGH TEMPERATURES
IN THE UPPER 80S AND 90S EXPECTED FOR THE MOST LOCATIONS BY LATE
NEXT WEEK. OVERNIGHT TEMPERATURES IN THE 60S ARE FORECAST FOR MOST
LOCATIONS THROUGH WEDNESDAY NIGHT...WITH LOWS CREEPING INTO THE
70S FOR SOME LOCATIONS BY LATE NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1255 AM CDT SUN JUN 16 2013
SHOWERS AND THUNDERSTORMS SHOULD STAY OUT OF THE KGRI AREA THROUGH
THE MORNING...BUT ARE EXPECTED TO MOVE BACK INTO THE KGRI VICINITY
LATER THIS AFTERNOON AND EVENING. SEVERAL MODELS ROLL
THUNDERSTORMS SOUTHEAST OUT OF THE NEBRASKA SANDHILLS THIS
AFTERNOON. SO THE AREA TO WATCH TODAY WILL BE TO OUR WEST AND
NORTHWEST. THE WIND WILL GENERALLY HAVE AN EASTERLY COMPONENT BUT
MAY VARY FROM NORTHEAST TO SOUTHEAST BASED ON WEAK BOUNDARIES IN
THE AREA. THE WIND COULD ALSO BECOME MUCH MORE ERRATIC WITHIN AND
NEAR THUNDERSTORMS LATER TODAY.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...EWALD
LONG TERM...BRYANT
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
329 AM CDT SUN JUN 16 2013
.DISCUSSION...
THE FORECAST ESSENTIALLY BREAKS DOWN INTO TWO PARTS...THE SEMI-
WET PERIOD FOR THE NEXT FEW DAYS...AND THE DRY AND WARM/HOT
PERIOD FOR LATE WEEK INTO THE WEEKEND.
ALTHOUGH THE MAIN TROUGH IS MOVING EASTWARD THIS MORNING...A WEAK
DISTURBANCE MAY STILL BRING ANOTHER CHANCE OF SHOWERS
THUNDERSTORMS TODAY. THE HIGH RESOLUTION RAPID REFRESH IS THE
MOST AGGRESSIVE IN GENERATING ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS THROUGH THIS AFTERNOON. THE NAM AND TEXAS TECH WRF
ON THE OTHER HAND SHOW LITTLE IF ANY PRECIPITATION TODAY. IT
APPEARS THAT THE HRRR MAY BE TOO AGGRESSIVE...SO HAVE JUST GONE
WITH 20 PERCENT POPS ACROSS ALL BUT THE EXTREME WESTERN ZONES FOR
TODAY WHERE HAVE PLACED 10 PERCENT POPS AND THE NORTHEAST WHERE
THERE ARE 30 PERCENT POPS FOR THIS AFTERNOON. THIS SEEMS TO BE
CLOSER TO WHAT THE GFS/ECMWF/CANADIAN ARE INDICATING. AS A
STRONGER SHORTWAVE SLIDES ACROSS THE CENTRAL PLAINS
TONIGHT...MOST OF THE RAIN WILL BE TO THE NORTH OF THE FORECAST
AREA BUT HAVE KEPT SOME 20 PERCENT POPS ALONG AND NORTH OF A
GRAHAM TO SULPHUR SPRINGS LINE. THERE IS PRETTY GOOD AGREEMENT
BETWEEN THE GFS...ECWMF...CANADIAN AND TO A LESSER DEGREE THE
NAM...THAT THAT A COUPLE OF SHORTWAVES MOVING ACROSS CENTRAL AND
SOUTHERN PLAINS WILL DRIVE A COLD FRONT INTO NORTH TEXAS MONDAY
NIGHT...AND STALL IT NEAR OR SOUTH OF THE I-20 CORRIDOR TUESDAY.
THE FRONT WILL THEN LIFT BACK TO THE NORTH ON WEDNESDAY. THE BEST
RAIN CHANCES WILL BE NEAR AND NORTH OF THIS FRONT...SO HAVE
PLACED 30-40 PERCENT POPS ACROSS THE NORTH...WITH ONLY 20 PERCENT
ACROSS THE SOUTH.
RAIN CHANCES WILL END LATE WEDNESDAY AS AN UPPER RIDGE STARTS TO
BUILD INTO THE SOUTHERN PLAINS IN THE WAKE OF THE UPPER TROUGH
MOVING EASTWARD AND AN INTENSE UPPER LEVEL STORM MOVING INTO THE
PACIFIC NORTHWEST. THE RIDGE WILL TAKE RESIDENCE OVER THE SOUTHERN
PLAINS LATE WEEK INTO THE WEEKEND...BRINGING ABOVE NORMAL HIGH
TEMPERATURES WITH NO SIGNIFICANT CHANCE OF RAIN.
58
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 93 76 93 73 87 / 20 10 20 40 30
WACO, TX 94 75 95 74 92 / 20 10 10 20 20
PARIS, TX 92 73 90 71 85 / 30 20 30 40 30
DENTON, TX 92 75 91 72 86 / 20 20 20 40 30
MCKINNEY, TX 92 74 92 71 86 / 20 20 20 40 30
DALLAS, TX 95 76 94 74 89 / 20 10 20 40 30
TERRELL, TX 94 74 93 73 89 / 20 10 20 30 30
CORSICANA, TX 94 74 94 73 91 / 20 10 10 20 20
TEMPLE, TX 93 74 93 72 93 / 20 10 10 20 20
MINERAL WELLS, TX 94 74 93 72 87 / 20 10 20 40 30
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
85/58
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1153 PM CDT SAT JUN 15 2013
.UPDATE...
SEE 06Z AVIATION DISCUSSION BELOW.
&&
.AVIATION...
VFR CONDITIONS WILL CONTINUE INTO THE EARLY MORNING HOURS ACROSS
WEST CENTRAL TEXAS...BUT LOW CLOUDS AND MVFR CIGS ARE EXPECTED TO
DEVELOP WELL BEFORE SUNRISE. STARTING TO SEE A HINT OF IT ON LOW
CLOUD IMAGERY...AND FULLY EXPECT THIS TO EXPAND OUT OVER THE NEXT
FEW HOURS. THE MVFR CIGS SHOULD PERSIST THROUGH SUNRISE...AND
THEN SLOWLY IMPROVE DURING DAYLIGHT HOURS.
&&
.PREV DISCUSSION... /ISSUED 656 PM CDT SAT JUN 15 2013/
UPDATE...
LATEST SATELLITE AND WSR-88D DATA INDICATE SHOWERS AND
THUNDERSTORMS HAVE DISSIPATED ACROSS WEST CENTRAL TEXAS. VISIBLE
SATELLITE LOOP SHOWS CLOUD MOVEMENT AT A COUPLE DIFFERENT LEVELS.
ONE...AT THE LOWEST LEVEL...INDICATES OPEN CELL CUMULUS MOVING
MAINLY TOWARD THE NORTHWEST ACROSS WEST CENTRAL TEXAS.
ALOFT...OTHER CLOUDS ARE MOVING TOWARD THE EAST OR SOUTHEAST. OVER
THE CONCHO VALLEY...DISSIPATING CUMULUS IMPLIES SUBSIDENCE. THE
MESOSCALE CONVECTIVE VORTEX SIGNATURES WE WERE OBSERVING EARLIER
TODAY IN THE VISIBLE IMAGERY APPEAR TO HAVE DISSIPATED. THE LATEST
RUC DATA INDICATES CONVECTION WILL BE LIMITED TO MAINLY OUR
NORTHWEST HILL COUNTRY AND HEARTLAND COUNTIES. HOWEVER...DYNAMICS
ALOFT LOOKS WEAK. THUS...I HAVE REDUCED POPS ACROSS THE SAME AREA
WE HAD IN OUR PREVIOUS FORECAST PACKAGE TO SLIGHT CHANCE FOR THE
REMAINDER OF TONIGHT. AGAIN...THE RUC INDICATES OUR SOUTHEASTERN
COUNTIES APPEAR TO BE THE BEST PLACE FOR RAIN FOR THE REMAINDER OF
TONIGHT. BUT...THE LATEST HPC QPF GUIDANCE GRIDS FOR TONIGHT HAVE
ZERO QPF FOR ALL OF WEST CENTRAL TEXAS.
I RECENTLY SENT A NEW SUITE OF PUBLIC AND FIRE ALPHANUMERIC
PRODUCTS TO REFLECT THESE CHANGES.
HUBER
PREV DISCUSSION... /ISSUED 622 PM CDT SAT JUN 15 2013/
DISCUSSION...
/SEE BELOW FOR AVIATION DISCUSSION/
AVIATION...
WITH A MOIST BOUNDARY LAYER IN PLACE AND PARTIALLY CLEARING
SKIES... EXPECT MVFR STRATUS TO RETURN AFTER 7Z TONIGHT...OVER
ALL BUT KABI. LIGHT MVFR FOG POSSIBLE TOWARDS MORNING WITH WET
VEGETATION. COULD SEE VISIBILITY DIPS INTO IFR...BUT SHOULD BRIEF
IF THEY OCCUR. CIGS RISE TO VFR BY LATE MORNING.
04
PREV DISCUSSION... /ISSUED 340 PM CDT SAT JUN 15 2013/
SHORT TERM...
CURRENTLY...VIS SATELLITE IMAGERY SHOWS AT LEAST TWO MCV/S IN OR
NEAR OUR CWA. ONE CAN BE SEEN TURNING OVER THE NORTHWEST CORNER OF
THE CWA...AND ANOTHER ONE IS MOVING NORTHWARD INTO CROCKETT AND
SONORA COUNTIES. THE SOUTHERN MCV APPEARS TO BE AIDING IN SCATTERED
NEW CONVECTIVE DEVELOPMENT SOUTH OF SAN ANGELO THIS AFTERNOON. AT
THE SAME TIME...A CU FIELD TO THE WEST OF THE CWA CAN BE SEEN
EVAPORATING FROM WEST TO EAST AS THE MAIN UPPER TROUGH MOVES EAST.
DEPENDING ON HOW FAST THE MAIN TROUGH CAN EXIT THE AREA...WE MAY
STILL SEE A REASONABLE CHANCE FOR ADDITIONAL CONVECTION LATER
TONIGHT AS THE MAIN TROUGH AXIS MOVES ACROSS THE AREA. HIGH
RESOLUTION MODELS AND THE GFS SEEM TO PICK UP ON THIS SHOWING
ADDITIONAL QPF ACROSS OUR SOUTHERN AREAS LATER TONIGHT. EXPECT
CHANCES TO FINALLY START TO DIMINISH MORE SUBSTANTIALLY AFTER
MIDNIGHT TONIGHT. AND IF ANY CLEARING OCCURS AS THE TROUGH AXIS
MOVES EAST...WE MIGHT EVEN SEE SOME PATCHY FOG IN WESTERN AREAS
WHERE HEAVIER PRECIPITATION FELL.
TEMPERATURES WILL BE SIMILAR TONIGHT TO LAST NIGHT WITH LOWS IN THE
UPPER 60S TO LOWER 70S. EXPECT WARMER TEMPERATURES ACROSS THE AREA
TOMORROW AS WE WILL SEE MUCH MORE SUNSHINE...AND NO RAINFALL. HAVE
TRIMMED POPS BACK IN THE NORTHWEST AS MOST OF THE POSSIBLE
CONVECTION TOMORROW AIS NOW EXPECTED TO OCCUR FARTHER WEST NEAR THE
TX/NM BORDER.
LONG TERM...
/SUNDAY NIGHT THROUGH SATURDAY/
COLD FRONT MAY BRING A CHANCE OF SHOWERS AND THUNDERSTORMS...
MAINLY TO THE BIG COUNTRY...MONDAY NIGHT INTO TUESDAY NIGHT.
AN UPPER RIDGE WILL BUILD IN FROM THE SOUTH TO NORTH THIS WEEK.
RIDGE WILL BE WEAK ENOUGH EARLY THIS WEEK...TO ALLOW DEVELOPMENT
OF SCATTERED THUNDERSTORMS ALONG A COLD FRONT...MONDAY NIGHT AND
TUESDAY. THE FRONT IS EXPECTED TO MOVE INTO THE THE RED RIVER
VALLEY MONDAY NIGHT...MOVING PERHAPS AS FAR SOUTH AS THE I-20
CORRIDOR. WHILE THE BEST CHANCE OF RAIN WILL BE IN THE BIG
COUNTRY... CANNOT RULE OUT POTENTIAL FOR STORM OUTFLOW TO PUSH
FARTHER SOUTH INTO THE CONCHO VALLEY AND HEARTLAND...LATE MONDAY
NIGHT INTO TUESDAY.
GFS SURFACE BASED CAPES INCREASE TO 1500-2000 J/KG OVER THE BIG
COUNTRY MONDAY INTO WEDNESDAY...SO A STRONG OR SEVERE
THUNDERSTORM POSSIBLE. HOWEVER UPPER DYNAMICS WILL BE NORTH OF
THE REGION...SO DO NOT EXPECT ORGANIZED SEVERE WEATHER. UPPER
RIDGING WILL BE BUILDING DIRECTLY OVER THE REGION THE SECOND HALF
OF NEXT WEEK...ENDING RAIN CHANCES AND BRINGING WARMER
TEMPERATURES.
04
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 70 94 73 94 71 / 10 10 10 20 30
SAN ANGELO 69 95 71 95 72 / 10 10 10 10 20
JUNCTION 71 93 71 93 71 / 20 5 5 10 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
348 AM CDT SUN JUN 16 2013
.UPDATE...
ISSUED AT 348 AM CDT SUN JUN 16 2013
HAVE EXPANDED THE DENSE FOG ADVISORY TO INCLUDE MUCH MORE OF
SOUTHWEST WISCONSIN AS WELL AS WINONA AND HOUSTON COUNTIES OF
MINNESOTA. CALLS TO COUNTY LAW ENFORCEMENTS AS WELL AS AUTOMATED
SURFACE OBSERVATIONS ARE SHOWING A LOT MORE VISIBILITIES OF 1/4
MILE OR LESS...INCLUDING VIROQUA...LA CROSSE...BLACK RIVER FALLS AND
WINONA. MOST RIVER VALLEYS OVER THE NORTHERN HALF OF THE FORECAST
AREA ARE ASSUMED TO BE SOCKED IN WITH FOG GIVEN THE CONDITIONS IN THE
MISSISSIPPI RIVER VALLEY. EXPECT ALL FOG TO DISSIPATE BY 9 AM WITH
THE EARLY SUNRISE HELPING TO MIX IT OUT QUICKLY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 307 AM CDT SUN JUN 16 2013
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED AN UPPER LOW OFF THE PACIFIC NORTHWEST COAST...AND NEARLY
ZONAL FLOW ACROSS MUCH OF THE NORTHERN U.S.. WITHIN THE ZONAL
FLOW...A COLLECTION OF SHORTWAVES...SOME CONVECTIVELY INDUCED...
EXTENDED FROM LOWER MICHIGAN INTO ARKANSAS. THESE SHORTWAVES HELPED
PRODUCE SOME OF THE CONVECTION YESTERDAY AFTERNOON AND EVENING. DRY
AIR HAS ADVECTED INTO THE FORECAST AREA BEHIND THE SHORTWAVES...
NOTED ON WATER VAPOR AS WELL AS THE 00Z MPX SOUNDING WHERE THE
PRECIPITABLE WATER HAS FALLEN TO 0.94 INCHES. FARTHER WEST...THE AIR
GETS EVEN DRIER...WITH THE 00Z ABR SOUNDING AT 0.34 INCHES FOR
PRECIPITABLE WATER. THE DRY AIR HAS EFFECTIVELY CLEARED MUCH OF THE
SKIES OUT. LIGHT WINDS...THE DRY AIR ALOFT AND PRECIPITATION LAST
EVENING HAS LED TO SOME FOG DEVELOPMENT... ESPECIALLY NORTH OF THE
I-94 CORRIDOR AS WELL AS IN THE MS RIVER VALLEY NORTH OF PRAIRIE DU
CHIEN. 850MB TEMPS DID NOT DROP MUCH WITH THE SHORTWAVE PASSAGE...
WITH READINGS GENERALLY 14-17C FROM THE DAKOTAS EAST INTO WISCONSIN.
MEANWHILE...TO THE NORTHWEST...AN UPPER LOW WAS SITTING OVER
SOUTHEAST SASKATCHEWAN. SOME CONVECTION FORMED AHEAD OF THE UPPER
LOW ALONG THE CANADIAN BORDER WITH NORTH DAKOTA AND MN DURING THE
DAYTIME HOURS YESTERDAY. THIS HAS SINCE MOSTLY DISSIPATED.
MAIN FOCUS IS ON THE UPPER LOW IN SOUTHEAST SASKATCHEWAN. MODELS
CONTINUE TO SHOW THE LOW DROPPING SOUTHEASTWARD AS IT BEGINS TO GET
CAUGHT UP IN THE CIRCULATION AROUND TROUGHING IN EASTERN CANADA. AT
THE SAME TIME...THE UPPER LOW IS PROGGED TO SHEAR OUT INTO A
SHORTWAVE. THERE ARE MODEL DIFFERENCES IN HOW FAR SOUTH THE
SHORTWAVE GETS TO AT 12Z MONDAY...RANGING FROM NEAR MINNEAPOLIS FROM
THE 16.00Z GFS TO NEAR BRAINERD MN FROM THE 16.00Z
NAM/UKMET/CANADIAN. THIS DIFFERENCE HAS IMPLICATIONS ON TIMING OF
POTENTIAL PRECIPITATION LATER TONIGHT.
TODAY CONTINUES TO LOOK QUIET AS WEST-NORTHWEST FLOW AHEAD OF THE
APPROACHING UPPER LOW/SHORTWAVE HELPS TO BRING THAT DRIER AIR IN
SEEN ON THE 00Z ABR SOUNDING. ANY CONVECTIVE ACTIVITY AHEAD OF THE
UPPER LOW/SHORTWAVE LIKE SEEN YESTERDAY AFTERNOON AND EVENING WILL
STAY NORTH AND WEST OF THE AREA. WE SHOULD SEE PLENTY OF
SUNSHINE...EASILY ALLOWING MIXING TO 850MB WHERE TEMPS OF 13-14C
WILL ALLOW FOR HIGHS IN THE LOW TO MID 80S. EXPECT ANY FOG THIS
MORNING TO QUICKLY DISSIPATE...LIKELY BY 9 AM OR EVEN EARLIER
GIVEN THE EARLY SUNRISE.
FOR TONIGHT...GOOD AGREEMENT EXISTS AMONGST MODELS THAT A SURGE OF
SOMEWHAT HIGHER PRECIPITABLE WATER WILL ADVECT INTO THE FORECAST
AREA AS THE UPPER LOW/SHORTWAVE DROPS INTO MN. VALUES CLIMB UP TO
AROUND 1 INCH. AT THE SAME TIME...THERE IS A DEFINITE SURGE OF 850MB
MOISTURE TRANSPORT TO HELP SUPPORT PRECIPITATION. BETWEEN THE
MOISTURE ADVECTION AND DPVA AHEAD OF THE UPPER LOW/SHORTWAVE...SOME
SCATTERED SHOWER AND THUNDERSTORM ACTIVITY SHOULD BE PRESENT AND
PERSIST THROUGH THE NIGHT. 16.00Z NAM/GFS/CANADIAN ALL INDICATE
PRECIPITATION...BUT IT IS JUST A MATTER HOW FAR SOUTH IT GETS WHICH
GOES BACK TO THE MODEL TIMING DIFFERENCES MENTIONED EARLIER. HAVE
FOLLOWED THE MAJORITY SOLUTION OF A SLOWER APPROACH...WHICH RESULTS
IN THE HIGHEST CHANCES OF 30-40 OVER THE NORTHERN 1/3 OF THE
FORECAST AREA. DID EXTEND A 20 PERCENT CHANCE DOWN INTO SOUTHEAST MN
IN THE EVENT THE FASTER 16.00Z GFS COMES TRUE. MOST OF THESE CHANCES
ARE ALSO AFTER MIDNIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 307 AM CDT SUN JUN 16 2013
MONDAY INTO MONDAY NIGHT...SHORTWAVE LURKING UP TO OUR NORTHWEST AT
12Z MONDAY IS WELL AGREED UPON TO REACH THE I-90 CORRIDOR IN THE
FORECAST AREA AT 00Z TUESDAY...DESPITE THE MODEL DIFFERENCES ON
TIMING BEFORE THAT. ACCOMPANYING THE SHORTWAVE WILL BE A COLD FRONT
WHICH SHOULD GRADUALLY MAKE ITS WAY SOUTH THROUGH THE AREA DURING
THE DAY. ANTICIPATING SCATTERED SHOWER/THUNDERSTORM ACTIVITY THAT
WAS DROPPING INTO NORTHERN PORTIONS OF THE AREA LATE SUNDAY NIGHT TO
CONTINUE DROPPING SOUTH AND POSSIBLY WEAKEN AS THE 850MB MOISTURE
TRANSPORT FALLS APART. AS INSTABILITY BUILDS DURING THE DAY...
THUNDERSTORMS MAY FORM BOTH ALONG THE COLD FRONT IN THE SOUTHERN
PORTION OF THE FORECAST AREA...AS WELL AS UNDER THE COLDER CORE OF
AIR ASSOCIATED WITH THE SHORTWAVE. THUS...IT APPEARS MONDAY WILL BE
AN OFF AND ON PRECIP DAY AT THIS TIME. 0-6KM SHEAR IS NOT THE
GREATEST FOR THINKING SEVERE WEATHER...GENERALLY 30-35 KT OVER THE
SOUTHERN TWO THIRDS OF THE AREA IN THE AFTERNOON. THIS WOULD SUGGEST
MOST OF THE CONVECTION TAKING ON A MULTI-CELLULAR APPEARANCE.
HOWEVER...FREEZING LEVELS DO LOWER AT 21Z TO 9000 FT OVER THE NORTH
TO 10500-11000 FT AGL IN THE SOUTH...SO HAIL IS A DEFINITE
POSSIBILITY FROM THE AFTERNOON STORMS. ANY CONVECTION FROM MONDAY
AFTERNOON SHOULD DIMINISH QUICKLY DURING THE EVENING WITH LOSS OF
DAYTIME HEATING...THE SHORTWAVE HEADING INTO NORTHERN ILLINOIS AND
HIGH PRESSURE BUILDING IN FROM THE NORTH.
TUESDAY INTO TUESDAY NIGHT...WHAT LOOKED TO BE A QUIET PERIOD FOR
MANY DAYS IS BECOMING A LITTLE MORE PROBLEMATIC. THE 15.00Z ECMWF
SHOWED A FAIRLY POTENT SHORTWAVE DROPPING THROUGH WESTERN PORTIONS
OF THE FORECAST AREA DURING THE DAYTIME HOURS ON TUESDAY. SO
ALTHOUGH A RIDGE OF HIGH PRESSURE IS IN PLACE AT THE SURFACE...THE
COLDER AIR ALOFT ACCOMPANYING THE SHORTWAVE RESULTED IN
PRECIPITATION. TODAY...THE 16.00Z NAM/UKMET/GFS/ECMWF/CANADIAN
CONTINUE TO SHOW THIS SHORTWAVE BUT ITS TRACK IS ALL OVER THE PLACE.
THE NAM/UKMET/ECMWF DROP IT SOUTHEAST THROUGH CENTRAL WI WHILE THE
GFS AND 15.12Z ECMWF BRING IT THROUGH SOUTHEAST MN AND NORTHEAST
IA. THE CANADIAN LIES BETWEEN THE TWO. FOR REFERENCE...THE SHORTWAVE
RIGHT NOW SITS ALONG THE SOUTHERN ALBERTA/SASKATCHEWAN BORDER.
DESPITE THE TRACK DIFFERENCES...LIGHT MODEL QPF IS MOSTLY CENTERED
WEST OF THE MS RIVER DURING THE TUESDAY DAYTIME HOURS. THIS AREA
APPEARS TO BE THE BEST JUXTAPOSITION OF DIURNAL HEATING/LOW LEVEL
MOISTENING AND THE COOL AIR ALOFT WITH THE SHORTWAVE. DESPITE SEEING
THE LIGHT QPF SIGNAL...HAVE CONTINUED TO STAY WITH THE DRY FORECAST
THINKING THAT THE MODELS MAY BE OVERDOING LOW LEVEL DEWPOINTS. A
NORTHEAST SURFACE FLOW OUT OF HIGH PRESSURE IN UPPER MI SHOULD
PROVIDE A DRY FLOW OF AIR. AFTER THE SHORTWAVE PASSES...A DRY AND
COOL NIGHT IS IN STORE FOR TUESDAY NIGHT AS HIGH PRESSURE SETTLES
IN.
WEDNESDAY THROUGH SATURDAY NIGHT...
THE UPPER LOW CURRENTLY SITTING OFF THE PACIFIC NORTHWEST COAST IS
FORECAST TO SLOWLY PUSH EAST THE NEXT FEW DAYS...ENCOMPASSING MUCH
OF THE PACIFIC NORTHWEST ON WEDNESDAY. DOWNSTREAM RIDGING SHOULD BE
IN PLACE FROM THE NORTHWEST TERRITORIES DOWN INTO THE SOUTHERN
PLAINS...PLACING THE FORECAST AREA IN SUBSIDENCE. MODELS REMAIN IN
GOOD AGREEMENT KEEPING THE AREA DRY WEDNESDAY AND WEDNESDAY
NIGHT...STAYING IN SUBSIDENCE AND DRY AIR WITH HIGH PRESSURE NEARBY
AT THE SURFACE. THE PATTERN THEN BEGINS TO CHANGE ACCORDING TO THE
16.00Z ECMWF/CANADIAN/GFS AND GFS ENSEMBLES...SUGGESTING THE
TROUGHING THAT HAS BEEN PERSISTENT OVER SOUTHEAST CANADA BEGINS TO
LIFT OUT. ADDITIONALLY...THE UPPER LOW IN THE PACIFIC NORTHWEST
SLOWLY EJECTS EAST-NORTHEAST. ALL THESE CHANGES OCCURRING TO THE
UPPER LEVEL PATTERN SETS UP WARM ADVECTION AND A DECENT RETURN OF
GULF OF MEXICO MOISTURE BACK TOWARDS THE UPPER MISSISSIPPI RIVER
VALLEY REGION. AS A RESULT...PRECIPITATION CHANCES BEGIN TO SLOWLY
INCREASE...AS EARLY AS THURSDAY. MUCH OF THE FORECAST FROM THURSDAY
NIGHT THROUGH SATURDAY NIGHT IS BROAD BRUSHED WITH 30-40 PERCENT
CHANCES AS THE FORECAST PATTERN LENDS ITSELF TO MULTIPLE ROUNDS OF
CONVECTION. WILL LIKELY HAVE TO WAIT MANY DAYS TO NAIL DOWN ANY
TIMING OR LOCATION OF THIS CONVECTION. CERTAINLY POTENTIAL HERE FOR
HEAVY RAIN...AND POSSIBLY SEVERE WEATHER TOO...BUT THOSE DETAILS ARE
TOO EARLY TO HASH OUT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 307 AM CDT SUN JUN 16 2013
FG/BR BECOMING A PROBLEM ALONG/EAST OF THE MS RIVER EARLY THIS
MORNING. WIND HAVE TRENDED LIGHTER THAN EARLIER EXPECTED. THESE
LIGHT/VARIABLE/CALM WINDS COMBINED WITH HIGH BOUNDARY LAYER MOISTURE
FROM RAINS SAT/SAT EVENING AND CLEAR/MOSTLY CLEAR SKIES HAVE
RESULTED IN MORE BR/FG FORMATION AT VALLEY SITES LIKE KLSE. EVEN
WITH A LIGHT WEST/NORTHWEST WINDS...SOME BR FORMING AT HIGHER
ELEVATION SITES ACROSS SOUTHEAST MN /KRST/KAUM/KTOB/.
MVFR/IFR CONDITIONS IN BR/FG CAN BE EXPECTED THRU THE MS/WI RIVER
VALLEYS /KLSE/ THRU 13Z...WITH SOME MVFR VSBYS AT KRST THRU THE SAME
TIME FRAME. GIVEN IT/S MID JUNE NEAR THE SUMMER SOLSTICE AND THE SUN
RISES AROUND 530 AM...THE FOG/BR SHOULD BURN OFF VERY QUICKLY THIS
MORNING...AND BE GONE BY 13Z/1330Z. GOOD VFR THEN EXPECTED THRU
SUN/SUN EVENING.
LATER SUNDAY NIGHT...A BOUNDARY TO THE NORTH WILL SINK SOUTH WITH
SOME WEAK MOISTURE TRANSPORT ALONG IT. A FEW SHRA/TS COULD SPARK
ALONG THE BOUNDARY...AND COULD IMPACT KRST/KLSE AFTER 06Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR WIZ017-029-
032>034-041>044-053.
MN...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR MNZ088-096.
IA...NONE.
&&
$$
UPDATE...AJ/RRS
SHORT TERM...AJ
LONG TERM...AJ
AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
308 AM CDT SUN JUN 16 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 307 AM CDT SUN JUN 16 2013
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED AN UPPER LOW OFF THE PACIFIC NORTHWEST COAST...AND NEARLY
ZONAL FLOW ACROSS MUCH OF THE NORTHERN U.S.. WITHIN THE ZONAL
FLOW...A COLLECTION OF SHORTWAVES...SOME CONVECTIVELY INDUCED...
EXTENDED FROM LOWER MICHIGAN INTO ARKANSAS. THESE SHORTWAVES HELPED
PRODUCE SOME OF THE CONVECTION YESTERDAY AFTERNOON AND EVENING. DRY
AIR HAS ADVECTED INTO THE FORECAST AREA BEHIND THE SHORTWAVES...
NOTED ON WATER VAPOR AS WELL AS THE 00Z MPX SOUNDING WHERE THE
PRECIPITABLE WATER HAS FALLEN TO 0.94 INCHES. FARTHER WEST...THE AIR
GETS EVEN DRIER...WITH THE 00Z ABR SOUNDING AT 0.34 INCHES FOR
PRECIPITABLE WATER. THE DRY AIR HAS EFFECTIVELY CLEARED MUCH OF THE
SKIES OUT. LIGHT WINDS...THE DRY AIR ALOFT AND PRECIPITATION LAST
EVENING HAS LED TO SOME FOG DEVELOPMENT... ESPECIALLY NORTH OF THE
I-94 CORRIDOR AS WELL AS IN THE MS RIVER VALLEY NORTH OF PRAIRIE DU
CHIEN. 850MB TEMPS DID NOT DROP MUCH WITH THE SHORTWAVE PASSAGE...
WITH READINGS GENERALLY 14-17C FROM THE DAKOTAS EAST INTO WISCONSIN.
MEANWHILE...TO THE NORTHWEST...AN UPPER LOW WAS SITTING OVER
SOUTHEAST SASKATCHEWAN. SOME CONVECTION FORMED AHEAD OF THE UPPER
LOW ALONG THE CANADIAN BORDER WITH NORTH DAKOTA AND MN DURING THE
DAYTIME HOURS YESTERDAY. THIS HAS SINCE MOSTLY DISSIPATED.
MAIN FOCUS IS ON THE UPPER LOW IN SOUTHEAST SASKATCHEWAN. MODELS
CONTINUE TO SHOW THE LOW DROPPING SOUTHEASTWARD AS IT BEGINS TO GET
CAUGHT UP IN THE CIRCULATION AROUND TROUGHING IN EASTERN CANADA. AT
THE SAME TIME...THE UPPER LOW IS PROGGED TO SHEAR OUT INTO A
SHORTWAVE. THERE ARE MODEL DIFFERENCES IN HOW FAR SOUTH THE
SHORTWAVE GETS TO AT 12Z MONDAY...RANGING FROM NEAR MINNEAPOLIS FROM
THE 16.00Z GFS TO NEAR BRAINERD MN FROM THE 16.00Z
NAM/UKMET/CANADIAN. THIS DIFFERENCE HAS IMPLICATIONS ON TIMING OF
POTENTIAL PRECIPITATION LATER TONIGHT.
TODAY CONTINUES TO LOOK QUIET AS WEST-NORTHWEST FLOW AHEAD OF THE
APPROACHING UPPER LOW/SHORTWAVE HELPS TO BRING THAT DRIER AIR IN
SEEN ON THE 00Z ABR SOUNDING. ANY CONVECTIVE ACTIVITY AHEAD OF THE
UPPER LOW/SHORTWAVE LIKE SEEN YESTERDAY AFTERNOON AND EVENING WILL
STAY NORTH AND WEST OF THE AREA. WE SHOULD SEE PLENTY OF
SUNSHINE...EASILY ALLOWING MIXING TO 850MB WHERE TEMPS OF 13-14C
WILL ALLOW FOR HIGHS IN THE LOW TO MID 80S. EXPECT ANY FOG THIS
MORNING TO QUICKLY DISSIPATE...LIKELY BY 9 AM OR EVEN EARLIER
GIVEN THE EARLY SUNRISE.
FOR TONIGHT...GOOD AGREEMENT EXISTS AMONGST MODELS THAT A SURGE OF
SOMEWHAT HIGHER PRECIPITABLE WATER WILL ADVECT INTO THE FORECAST
AREA AS THE UPPER LOW/SHORTWAVE DROPS INTO MN. VALUES CLIMB UP TO
AROUND 1 INCH. AT THE SAME TIME...THERE IS A DEFINITE SURGE OF 850MB
MOISTURE TRANSPORT TO HELP SUPPORT PRECIPITATION. BETWEEN THE
MOISTURE ADVECTION AND DPVA AHEAD OF THE UPPER LOW/SHORTWAVE...SOME
SCATTERED SHOWER AND THUNDERSTORM ACTIVITY SHOULD BE PRESENT AND
PERSIST THROUGH THE NIGHT. 16.00Z NAM/GFS/CANADIAN ALL INDICATE
PRECIPITATION...BUT IT IS JUST A MATTER HOW FAR SOUTH IT GETS WHICH
GOES BACK TO THE MODEL TIMING DIFFERENCES MENTIONED EARLIER. HAVE
FOLLOWED THE MAJORITY SOLUTION OF A SLOWER APPROACH...WHICH RESULTS
IN THE HIGHEST CHANCES OF 30-40 OVER THE NORTHERN 1/3 OF THE
FORECAST AREA. DID EXTEND A 20 PERCENT CHANCE DOWN INTO SOUTHEAST MN
IN THE EVENT THE FASTER 16.00Z GFS COMES TRUE. MOST OF THESE CHANCES
ARE ALSO AFTER MIDNIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 307 AM CDT SUN JUN 16 2013
MONDAY INTO MONDAY NIGHT...SHORTWAVE LURKING UP TO OUR NORTHWEST AT
12Z MONDAY IS WELL AGREED UPON TO REACH THE I-90 CORRIDOR IN THE
FORECAST AREA AT 00Z TUESDAY...DESPITE THE MODEL DIFFERENCES ON
TIMING BEFORE THAT. ACCOMPANYING THE SHORTWAVE WILL BE A COLD FRONT
WHICH SHOULD GRADUALLY MAKE ITS WAY SOUTH THROUGH THE AREA DURING
THE DAY. ANTICIPATING SCATTERED SHOWER/THUNDERSTORM ACTIVITY THAT
WAS DROPPING INTO NORTHERN PORTIONS OF THE AREA LATE SUNDAY NIGHT TO
CONTINUE DROPPING SOUTH AND POSSIBLY WEAKEN AS THE 850MB MOISTURE
TRANSPORT FALLS APART. AS INSTABILITY BUILDS DURING THE DAY...
THUNDERSTORMS MAY FORM BOTH ALONG THE COLD FRONT IN THE SOUTHERN
PORTION OF THE FORECAST AREA...AS WELL AS UNDER THE COLDER CORE OF
AIR ASSOCIATED WITH THE SHORTWAVE. THUS...IT APPEARS MONDAY WILL BE
AN OFF AND ON PRECIP DAY AT THIS TIME. 0-6KM SHEAR IS NOT THE
GREATEST FOR THINKING SEVERE WEATHER...GENERALLY 30-35 KT OVER THE
SOUTHERN TWO THIRDS OF THE AREA IN THE AFTERNOON. THIS WOULD SUGGEST
MOST OF THE CONVECTION TAKING ON A MULTI-CELLULAR APPEARANCE.
HOWEVER...FREEZING LEVELS DO LOWER AT 21Z TO 9000 FT OVER THE NORTH
TO 10500-11000 FT AGL IN THE SOUTH...SO HAIL IS A DEFINITE
POSSIBILITY FROM THE AFTERNOON STORMS. ANY CONVECTION FROM MONDAY
AFTERNOON SHOULD DIMINISH QUICKLY DURING THE EVENING WITH LOSS OF
DAYTIME HEATING...THE SHORTWAVE HEADING INTO NORTHERN ILLINOIS AND
HIGH PRESSURE BUILDING IN FROM THE NORTH.
TUESDAY INTO TUESDAY NIGHT...WHAT LOOKED TO BE A QUIET PERIOD FOR
MANY DAYS IS BECOMING A LITTLE MORE PROBLEMATIC. THE 15.00Z ECMWF
SHOWED A FAIRLY POTENT SHORTWAVE DROPPING THROUGH WESTERN PORTIONS
OF THE FORECAST AREA DURING THE DAYTIME HOURS ON TUESDAY. SO
ALTHOUGH A RIDGE OF HIGH PRESSURE IS IN PLACE AT THE SURFACE...THE
COLDER AIR ALOFT ACCOMPANYING THE SHORTWAVE RESULTED IN
PRECIPITATION. TODAY...THE 16.00Z NAM/UKMET/GFS/ECMWF/CANADIAN
CONTINUE TO SHOW THIS SHORTWAVE BUT ITS TRACK IS ALL OVER THE PLACE.
THE NAM/UKMET/ECMWF DROP IT SOUTHEAST THROUGH CENTRAL WI WHILE THE
GFS AND 15.12Z ECMWF BRING IT THROUGH SOUTHEAST MN AND NORTHEAST
IA. THE CANADIAN LIES BETWEEN THE TWO. FOR REFERENCE...THE SHORTWAVE
RIGHT NOW SITS ALONG THE SOUTHERN ALBERTA/SASKATCHEWAN BORDER.
DESPITE THE TRACK DIFFERENCES...LIGHT MODEL QPF IS MOSTLY CENTERED
WEST OF THE MS RIVER DURING THE TUESDAY DAYTIME HOURS. THIS AREA
APPEARS TO BE THE BEST JUXTAPOSITION OF DIURNAL HEATING/LOW LEVEL
MOISTENING AND THE COOL AIR ALOFT WITH THE SHORTWAVE. DESPITE SEEING
THE LIGHT QPF SIGNAL...HAVE CONTINUED TO STAY WITH THE DRY FORECAST
THINKING THAT THE MODELS MAY BE OVERDOING LOW LEVEL DEWPOINTS. A
NORTHEAST SURFACE FLOW OUT OF HIGH PRESSURE IN UPPER MI SHOULD
PROVIDE A DRY FLOW OF AIR. AFTER THE SHORTWAVE PASSES...A DRY AND
COOL NIGHT IS IN STORE FOR TUESDAY NIGHT AS HIGH PRESSURE SETTLES
IN.
WEDNESDAY THROUGH SATURDAY NIGHT...
THE UPPER LOW CURRENTLY SITTING OFF THE PACIFIC NORTHWEST COAST IS
FORECAST TO SLOWLY PUSH EAST THE NEXT FEW DAYS...ENCOMPASSING MUCH
OF THE PACIFIC NORTHWEST ON WEDNESDAY. DOWNSTREAM RIDGING SHOULD BE
IN PLACE FROM THE NORTHWEST TERRITORIES DOWN INTO THE SOUTHERN
PLAINS...PLACING THE FORECAST AREA IN SUBSIDENCE. MODELS REMAIN IN
GOOD AGREEMENT KEEPING THE AREA DRY WEDNESDAY AND WEDNESDAY
NIGHT...STAYING IN SUBSIDENCE AND DRY AIR WITH HIGH PRESSURE NEARBY
AT THE SURFACE. THE PATTERN THEN BEGINS TO CHANGE ACCORDING TO THE
16.00Z ECMWF/CANADIAN/GFS AND GFS ENSEMBLES...SUGGESTING THE
TROUGHING THAT HAS BEEN PERSISTENT OVER SOUTHEAST CANADA BEGINS TO
LIFT OUT. ADDITIONALLY...THE UPPER LOW IN THE PACIFIC NORTHWEST
SLOWLY EJECTS EAST-NORTHEAST. ALL THESE CHANGES OCCURRING TO THE
UPPER LEVEL PATTERN SETS UP WARM ADVECTION AND A DECENT RETURN OF
GULF OF MEXICO MOISTURE BACK TOWARDS THE UPPER MISSISSIPPI RIVER
VALLEY REGION. AS A RESULT...PRECIPITATION CHANCES BEGIN TO SLOWLY
INCREASE...AS EARLY AS THURSDAY. MUCH OF THE FORECAST FROM THURSDAY
NIGHT THROUGH SATURDAY NIGHT IS BROAD BRUSHED WITH 30-40 PERCENT
CHANCES AS THE FORECAST PATTERN LENDS ITSELF TO MULTIPLE ROUNDS OF
CONVECTION. WILL LIKELY HAVE TO WAIT MANY DAYS TO NAIL DOWN ANY
TIMING OR LOCATION OF THIS CONVECTION. CERTAINLY POTENTIAL HERE FOR
HEAVY RAIN...AND POSSIBLY SEVERE WEATHER TOO...BUT THOSE DETAILS ARE
TOO EARLY TO HASH OUT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 307 AM CDT SUN JUN 16 2013
FG/BR BECOMING A PROBLEM ALONG/EAST OF THE MS RIVER EARLY THIS
MORNING. WIND HAVE TRENDED LIGHTER THAN EARLIER EXPECTED. THESE
LIGHT/VARIABLE/CALM WINDS COMBINED WITH HIGH BOUNDARY LAYER MOISTURE
FROM RAINS SAT/SAT EVENING AND CLEAR/MOSTLY CLEAR SKIES HAVE
RESULTED IN MORE BR/FG FORMATION AT VALLEY SITES LIKE KLSE. EVEN
WITH A LIGHT WEST/NORTHWEST WINDS...SOME BR FORMING AT HIGHER
ELEVATION SITES ACROSS SOUTHEAST MN /KRST/KAUM/KTOB/.
MVFR/IFR CONDITIONS IN BR/FG CAN BE EXPECTED THRU THE MS/WI RIVER
VALLEYS /KLSE/ THRU 13Z...WITH SOME MVFR VSBYS AT KRST THRU THE SAME
TIME FRAME. GIVEN IT/S MID JUNE NEAR THE SUMMER SOLSTICE AND THE SUN
RISES AROUND 530 AM...THE FOG/BR SHOULD BURN OFF VERY QUICKLY THIS
MORNING...AND BE GONE BY 13Z/1330Z. GOOD VFR THEN EXPECTED THRU
SUN/SUN EVENING.
LATER SUNDAY NIGHT...A BOUNDARY TO THE NORTH WILL SINK SOUTH WITH
SOME WEAK MOISTURE TRANSPORT ALONG IT. A FEW SHRA/TS COULD SPARK
ALONG THE BOUNDARY...AND COULD IMPACT KRST/KLSE AFTER 06Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR WIZ017-029.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1115 AM EDT SUN JUN 16 2013
.SYNOPSIS...
A WEAK DISTURBANCE WILL CROSS THE REGION TODAY...BRINGING SHOWERS
AND POSSIBLY AN ISOLATED THUNDERSTORM. A FRONTAL BOUNDARY WILL SAG
SOUTHEASTWARD INTO THE AREA TONIGHT INTO MONDAY...WITH A LOW
CHANCE FOR SHOWERS THROUGH THIS PERIOD. THE FRONT WILL PUSH
SOUTHEAST OF THE AREA LATE ON TUESDAY AND HIGH PRESSURE WILL THEN
BUILD IN FROM THE NORTHWEST AND ALLOW FOR A DRY MID-WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
15Z ENHANCED SHORT TERM FORECAST HAS BEEN ISSUED TO INCREASE
POP...USING COVERAGE WORDING THROUGH THE EARLY AFTERNOON. IN
ADDITION...WITH EXTENSIVE CLOUD COVERAGE ACROSS THE OHIO
VALLEY...HAVE LOWERED HIGH TEMPS TODAY 1-2 DEGREES.
THE LATEST RAP UPPER LEVEL ANALYSIS INDICATES THE UPPER OHIO VALLEY
IN A ZONAL FLOW WITH A 300MB 100KT JET AXIS CENTERED OVER LAKE
HURON. AT THE MID-LEVELS...A 500MB SHORT WAVE IS WEAKENING AS IT
MOVES EASTWARD ACROSS OHIO. AT THE SURFACE...A 1005MB SURFACE LOW IS
LOCATED NORTH OF LAKE SUPERIOR WITH A ILL-DEFINED FRONTAL BOUNDARY
EXTENDING SOUTH OF THIS FEATURE ACROSS SOUTHERN MICHIGAN. WELL AHEAD
OF THE FRONT...WEAK 700-500MB VORT ENERGY ALONG WITH A MOIST
800-650MB LAYER ARE SUPPORTING SCATTERED SHOWERS MOVING ACROSS THE
AREA. THE 12Z KPIT SOUNDING SHOWS THE AFOREMENTIONED MOIST LAYER
WITH WEAK SBCAPE (APPROX 100 J/KG) WITH A UNIDIRECTIONAL ZONAL
PROFILE THROUGH MUCH OF THE COLUMN.
THIS AFTERNOON...THE SHORT WAVE WILL CONTINUE TO WEAKEN AS IT MOVES
INTO WESTERN PENNSYLVANIA AND THE FRONTAL BOUNDARY WILL SAG FURTHER
SOUTHEASTWARD INTO OHIO. FORCING FROM THE WAVE WILL ALLOW FOR
SCATTERED SHOWERS TO CONTINUE INTO THE EARLY AFTERNOON. SOME
UNCERTAINTY COMES INTO THE FORECAST IN THE 18Z-00Z WINDOW AS HIRES
MODEL SOLUTIONS VARY IN RESOLVING CONVECTION THIS AFTERNOON.
HRRR/WRF-NMM SUPPORT THE DEVELOPMENT OF THUNDERSTORMS ALONG THE
FRONTAL BOUNDARY WHILE THE NAM 4KM INDICATES SHOWERS MORE LIMITED.
WITH EXTENSIVE UPSTREAM CLOUD COVERAGE...BELIEVE THIS WILL INHIBIT
CONVECTIVE TEMPS FROM BEING REACHED. THUS...HAVE GONE WITH
SCATTERED/NUMEROUS SHOWERS AND ISOLATED THUNDERSTORM WORDING TO NOT
COMPLETELY DISCOUNT THE HRRR/WRF-NMM SOLUTIONS. WITH ALL OF THIS
IN MIND...THE STORM PREDICTION CENTER HAS MENTIONED THE AREA IN
ITS SEE TEXT...CONSIDERING THE LOW PROB SCENARIO THAT IF CLOUD COVERAGE
BREAKS THEN THE UNIDIRECTIONAL SHEAR ENVIRONMENT WOULD BE
FAVORABLE FOR A POSSIBLE EWD MOVING STRONG TO SEVERE CONVECTIVE
CLUSTER IN THE 18Z-00Z TIME FRAME. TEMPS HAVE BEEN LOWERED A FEW
DEGREES CLOSER TO LAMP GUIDANCE...WITH HIGHS RANGING FROM THE
LOWER TO MID 70S ACROSS THE AREA.
TONIGHT...THE FRONTAL BOUNDARY WILL CONTINUE TO SAG SOUTHEASTWARD
ACROSS THE AREA...WITH ANY LINGERING COVERAGE OF SHOWERS MOSTLY
DIMINISHING BY 06Z. MOSTLY CLOUDY SKIES WILL BEGIN TO GIVE WAY TO
MORE BREAKS IN CLOUD COVERAGE WITH SHOWERS COMING TO AN END AS A
POCKET OF DRIER AIR ADVECTS IN FROM THE NORTHWEST. CLOUD COVERAGE
FOR MUCH OF THE NIGHT WILL SERVE TO MODERATE LOW TEMPS. FORECAST IS
CLOSEST TO THE WARMER MAV...WITH LOWS RANGING FROM THE LOWER TO MID
60S ACROSS THE AREA.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
HAVE BACKED OFF POPS ON MONDAY DOWN TO SLIGHT CHANCE. FORECAST AREA
SHOULD BE IN THE DRY REGION BETWEEN FRONTS TO THE NORTH AND
SOUTH...AND DO NOT SEE MUCH OF A TRIGGER TO GET PRECIP GOING. MONDAY
NIGHT AND TUESDAY THE NAM/SREF ARE AGGRESSIVE SWEEPING THE NORTHERN
FRONT ACROSS THE REGION AND BRINGING WIDESPREAD PRECIPITATION. WITH
THE ECMWF SHOWING MORE CONSISTENCY...KEEPING THE NORTHERN FRONT DRY
AND FOCUSING PRECIPITATION ALONG THE SOUTHERN FRONT...AND THE GFS
AND GEFS COMING INTO LINE WITH THE ECMWF SOLUTION...HAVE BACKED OFF
POPS ACROSS THE NORTHERN HALF OF THE REGION FOR MON NIGHT/TUES.
ONCE THE FRONT MOVES OFF TO THE EAST...THE ENTIRE AREA SHOULD BE
DRY TUESDAY NIGHT AND WEDNESDAY WITH HIGH PRESSURE MOVING IN FROM
MICHIGAN. LIGHT NORTHERLY FLOW THROUGH THIS TIME PERIOD SHOULD
KEEP TEMPERATURES A FEW DEGREES BELOW NORMAL.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
LATEST GFS AND ECMWF DETERMINISTIC SOLNS AGREED GENLY IN
DEPICTIONS OF THE PROGGED FLOW PTN OVR THE ERN CONUS FOR THE
LATTER HALF OF THE WEEK...WITH ECMWF AMPLIFYING THE PTN CLOSER TO
GFS WITH A RIDGE AXIS EXTENDING FM THE SRN PLNS ACRS THE GREAT
LAKES.
THE LONG TERM FORECAST THUS CONSERVATIVELY FEATURES TEMPS
GRADUALLY WARMING TO SLIGHTLY ABOVE THE SEASONAL AVERAGES BY THE
WEEKEND. PCPN CHCS WERE FORECAST AOB CLIMO NMBRS...BUT WERE GENLY
INCRSD USING A GFS/ECMWF BLEND FOR SHRTWV TIMING INTO THE WEEKEND.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
AN APPROACHING SHORTWAVE AND ASSOCIATED COLD FRONT WILL BRING
SHWRS AND INCRSD EMBEDDED TSTM CHCS TDA. FOR NOW...GIVEN A LACK OF
CONFIDENCE IN INSTABILITY PROGS...WL KP MENTION OF THUNDER OUT OF
ANY SPECIFIC TAF SITE. A GRADUAL DETERIORATION TO MVFR CAN BE
EXPECTED...WITH ISOLD IFR IN HEAVIER SHWRS.
.OUTLOOK.../MONDAY THROUGH THURSDAY/...
PERIODIC RESTRICTIONS ARE ANTICIPATED THROUGH TUESDAY AS ANOTHER
LOW APPRCHS AND CROSSES THE REGION. BLDG HIGH PRES SHOULD RTN VFR
CONDITIONS FOR WEDNESDAY AND THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
SYNOPSIS...WOODRUM
NEAR TERM...WOODRUM
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
749 AM EDT SUN JUN 16 2013
.SYNOPSIS...
SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY...WITH THE POSSIBILITY
FOR PERIODIC RAIN CONTINUING MONDAY AND TUESDAY. CONDITIONS
SHOULD THEN DRY OUT FOR THE REST OF THE WORK WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATED PROBALIBILITES OF PRECIPITATION SLIGHTLY DUE TO RADAR
SHOWING MEASURABLE PRECIP FARTHER SOUTH
PREVIOUS DISCUSSION...
LINE OF SHOWERS AND THUNDERSTORMS ACROSS LOWER MICHIGAN AND
NORTHERN INDIANA HAS MANAGED TO HOLD UP FAIRLY WELL CONSIDERING
THE TIME OF DAY. HOWEVER...DO NOT THINK THIS LINE WILL BE ABLE TO
MAINTAIN ITSELF ALL THE WAY INTO NORTHEASTERN OHIO AND
NORTHWESTERN PENNSYLVANIA. 04Z HRRR INDICATES THE LINE MAY PASS TO
THE NORTH AROUND SUNRISE. NEVERTHELESS...SOME LIGHT SPRINKLES ARE
EXPECTED OVERNIGHT...AND COVERAGE OF SHOWERS WILL INCREASE AS THE
MORNING PROGRESSES. CONTINUED PREVIOUS FORECAST WITH LIKELY POPS
MOVING FROM NORTH TO SOUTH DURING THE DAY. CANNOT RULE OUT A
STRONG/SEVERE THUNDERSTORM...BUT AM NOT OVERLY IMPRESSED WITH THE
SETUP. MODEL SOUNDINGS SHOW MODERATE LEVELS OF INSTABILITY AND
SHEAR ALONG THE FRONT ITSELF...BUT LOOKING AT HIGH-RESOLUTION
MODEL REFLECTIVITIES...MOST OF THE PRECIPITATION WILL OCCUR WELL
AHEAD OF THE FRONT ITSELF. MODEL SOUNDINGS IN THE REGIONS WITH
PRECIPITATION SHOW A BIT LESS INSTABILITY DUE TO WEAK LOW-LEVEL
LAPSE RATES. WHILE SHOWERS WILL CONTINUE INTO THE EVENING...THINK
THAT MOST RAINFALL ACTIVITY WILL BE CONFINED TO LOCATIONS SOUTH OF
THE MASON-DIXON LINE AFTER MIDNIGHT. WITH THE WIDESPREAD CLOUD
COVER...DAYTIME TEMPS WILL BE A FEW DEGREES COOLER THAN
YESTERDAY...AND OVERNIGHT LOWS SHOULD BE SIMILAR TO CURRENT
READINGS.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
HAVE BACKED OFF POPS ON MONDAY DOWN TO SLIGHT CHANCE. FORECAST AREA
SHOULD BE IN THE DRY REGION BETWEEN FRONTS TO THE NORTH AND
SOUTH...AND DO NOT SEE MUCH OF A TRIGGER TO GET PRECIP GOING. MONDAY
NIGHT AND TUESDAY THE NAM/SREF ARE AGGRESSIVE SWEEPING THE NORTHERN
FRONT ACROSS THE REGION AND BRINGING WIDESPREAD PRECIPITATION. WITH
THE ECMWF SHOWING MORE CONSISTENCY...KEEPING THE NORTHERN FRONT DRY
AND FOCUSING PRECIPITATION ALONG THE SOUTHERN FRONT...AND THE GFS
AND GEFS COMING INTO LINE WITH THE ECMWF SOLUTION...HAVE BACKED OFF
POPS ACROSS THE NORTHERN HALF OF THE REGION FOR MON NIGHT/TUES.
ONCE THE FRONT MOVES OFF TO THE EAST...THE ENTIRE AREA SHOULD BE
DRY TUESDAY NIGHT AND WEDNESDAY WITH HIGH PRESSURE MOVING IN FROM
MICHIGAN. LIGHT NORTHERLY FLOW THROUGH THIS TIME PERIOD SHOULD
KEEP TEMPERATURES A FEW DEGREES BELOW NORMAL.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
LATEST GFS AND ECMWF DETERMINISTIC SOLNS AGREED GENLY IN
DEPICTIONS OF THE PROGGED FLOW PTN OVR THE ERN CONUS FOR THE
LATTER HALF OF THE WEEK...WITH ECMWF AMPLIFYING THE PTN CLOSER TO
GFS WITH A RIDGE AXIS EXTENDING FM THE SRN PLNS ACRS THE GREAT
LAKES.
THE LONG TERM FORECAST THUS CONSERVATIVELY FEATURES TEMPS
GRADUALLY WARMING TO SLIGHTLY ABOVE THE SEASONAL AVERAGES BY THE
WEEKEND. PCPN CHCS WERE FORECAST AOB CLIMO NMBRS...BUT WERE GENLY
INCRSD USING A GFS/ECMWF BLEND FOR SHRTWV TIMING INTO THE WEEKEND.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AN APPROACHING SHORTWAVE AND ASSOCIATED COLD FRONT WILL BRING
SHWRS AND INCRSD EMBEDDED TSTM CHCS TDA. FOR NOW...GIVEN A LACK OF
CONFIDENCE IN INSTABILITY PROGS...WL KP MENTION OF THUNDER OUT OF
ANY SPECIFIC TAF SITE. A GRADUAL DETERIORATION TO MVFR CAN BE
EXPECTED...WITH ISOLD IFR IN HEAVIER SHWRS.
.OUTLOOK.../MONDAY THROUGH THURSDAY/...
PERIODIC RESTRICTIONS ARE ANTICIPATED THROUGH TUESDAY AS ANOTHER
LOW APPRCHS AND CROSSES THE REGION. BLDG HIGH PRES SHOULD RTN VFR
CONDITIONS FOR WEDNESDAY AND THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1151 AM EDT SUN JUN 16 2013
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OVER OUR REGION TODAY. A COLD FRONT WILL
APPROACH FROM THE NORTHWEST MONDAY AND MOVE ACROSS OUR REGION LATE
TUESDAY INTO EARLY WEDNESDAY MORNING.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1150 AM SUNDAY...
THE UPPER RIDGE WILL CONTINUE TO FLATTEN TODAY AS SURFACE HIGH
PRESSURE CONTINUES TO MOVE OFF TO THE SOUTHEAST...AND THE GRADIENT
TIGHTENS BETWEEN THE RETREATING HIGH AND SURFACE TROUGHINESS
SHARPENING OVER THE WESTERN PART OF THE STATE. THE 12Z KGSO
SOUNDING...AS WELL AS THE SOUNDING FROM KMHX...SHOWED A DECENT CAP
REMAINING AROUND 700MB...WHILE THE KRNK SOUNDING INDICATED JUST
SLIGHTLY COOLER TEMPERATURES JUST ABOVE 700MB ALBEIT WITH A WEAK CAP
IN PLACE. THE RAP SOUNDINGS FORECAST THIS CAP ESSENTIALLY REMAINING
FOR THE REST OF THE DAY...VERY GRADUALLY DIMINISHING ESPECIALLY
TOWARD THE NORTHWEST PIEDMONT AS THE RIDGE FLATTENS...UPPER LEVELS
COOL...AND THE OVERALL MOISTURE OF THE AIR MASS INCREASES. THE RAP
FORECASTS 850MB SUBSIDENCE THROUGHOUT THE DAY...WITH ANY MODEST UVV
WITH APPROACHING MID-LEVEL SHORTWAVES HOLDING OFF UNTIL 00Z AND
AFTER. THE LATEST HRRR WRF IS DRY AS WELL...ALONG WITH QPF FROM THE
RAP. WILL CONTINUE WITH A DRY FORECAST TODAY...AND EXPECT PERIODS OF
MOSTLY MID- AND SOME HIGH-LEVEL CLOUDS TO RESULT IN A
PARTLY-TO-MOSTLY SUNNY LATE MORNING AND AFTERNOON. ALREADY THERE
HAVE BEEN A FEW WIND GUSTS IN THE TEENS KNOTS AND...BASED ON THE
LATEST RAP SOUNDINGS AND THE WINDS ALOFT ON THE KRAX 88D VAD WIND
PROFILE...INCREASED THE GUSTS A TRIFLE ESPECIALLY OUTSIDE OF
SOUTHEAST AREAS TO MORE AROUND 20KT. WHILE THE MAV MOS HAS SIMPLY
BEEN TOO WARM OF LATE...THE MET MOS IS CLOSER TODAY TO THE MAV AND
TO THE ONGOING FORECAST. LOWERED A DEGREE TOWARD KRWI BASED ON THE
LATEST TRENDS AND MOS...AND AS A RESULT OF SLIGHTLY COOLER
1000-850MB THICKNESSES COMPARED TO THE REST OF CENTRAL NORTH
CAROLINA. STILL...HIGHS 85 TO 90.
THE VERY LATEST GUIDANCE HAS BEEN A LITTLE MORE AGGRESSIVE WITH THE
POTENTIAL FOR AT LEAST LIGHT QPF MOVING IN A LITTLE MORE IN EARNEST
INTO NORTHERN AREAS OVERNIGHT...MAINLY AFTER 02Z OR SO. MID-LEVEL
COOLING AND OVERALL MOISTENING ON THE NAM IS EFFICIENT OVERNIGHT...
AND THE LATEST HRRR WRF SUGGESTS UPSTREAM PRECIPITATION CURRENTLY
OVER SOUTHERN ILLINOIS INTO KENTUCKY ABLE TO MAKE STEADY PROGRESS
EAST-SOUTHEAST INTO AT LEAST THE TRIAD AND TOWARD KTDF AS
MOISTENING...AND COOLING ALOFT...OCCUR. FOR THE LATE MORNING
UPDATE...RAISED POPS INTO CHANCE FOR THAT AREA. WILL NOTE THE LATEST
NAM MOS GUIDANCE IS INTO CATEGORICAL IN THE TRIAD FOR THE OVERNIGHT
HOURS...DIMINISHING BUT STILL HIGHER ELSEWHERE. AFTER A REVIEW OF
THE GFS...MAY NEED TO SHOW SOME FURTHER INCREASE FOR MANY PARTS OF
CENTRAL NORTH CAROLINA OVERNIGHT. OTHERWISE...CLOUDINESS...AGAIN
MAINLY MID AND UPPER...WILL BECOME PREVALENT TONIGHT AS THE
APPROACHING FRONT TRANSLATES INTO THE LEE TROUGH. MINS WILL BE MILD
AND SEASONABLE...UPPER 60S.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 315 AM SUNDAY...
MONDAY AND MONDAY NIGHT...TRANSITION TO A BROAD LONGWAVE TROF WILL
BE UNDERWAY AND THE LINGERING LOW LEVEL TROFFING ALONG THE ATLANTIC
SEABOARD WILL PROMOTE AN INCREASINGLY MOIST AIRMASS. THICKNESSES ARE
RELATIVELY HIGH AND SIMILAR TO SUNDAY...WITH THE POTENTIAL FOR UPPER
80S. MOSTLY CLOUDY SKIES WILL HAMPER INSOLATION A BIT...MOSTLY MID
80S WEST TO UPPER 80S EAST. CHANCES OF SHOWERS WILL INCREASE MONDAY
AFTERNOON INTO MONDAY NIGHT IN INCREASINGLY DISTURBED FLOW...BUT ITS
DIFFICULT TO PICK OUT A PARTICULAR FEATURE DURING THIS TIME FRAME TO
FOCUS ACTIVITY...WILL CONTINUE CHANCE CATEGORY POPS FAVORING THE
WEST AND NORTH.
TUESDAY AND TUESDAY NIGHT: WITHIN A BROAD TROUGH ALOFT EAST OF THE
ROCKIES...A LOW AMPLITUDE SOUTHERN STREAM SHORTWAVE TROUGH...AND
PERHAPS A PRECEDING MCV FROM CONVECTION INITIATED AHEAD OF THIS WAVE
OVER THE CENTRAL PLAINS LATER TODAY AND TONIGHT...WILL MIGRATE
THROUGH THE BASE OF THE TROUGH/ACROSS THE CENTRAL APPALACHIANS AND
MIDDLE ATLANTIC REGION TUE. THESE FEATURES WILL BE FOLLOWED QUICKLY
BY AN ELONGATED BUT STRONGER NORTHERN STREAM WAVE IN NW FLOW FROM
THE UPPER MIDWEST TO THE CENTRAL APPALACHIANS TUE NIGHT.
IN THE LOW LEVELS...A PRE-FRONTAL TROUGH OVER VA/NC TUE WILL BE
OVERTAKEN BY A COLD FRONT ATTENDING THE AFOREMENTIONED NORTHERN
STREAM S/W TROUGH...AND THIS MERGED BOUNDARY WILL SETTLE SOUTHWARD
ACROSS CENTRAL NC TUE NIGHT. WITH A CONDITIONALLY UNSTABLE AND
UNCAPPED ENVIRONMENT PER BUFR SOUNDINGS...AND WITH FORECAST
PRECIPITABLE WATER VALUES APPROACHING TWO INCHES...THE WEAK (~20
METER/12 HR) HEIGHT FALLS ASSOCIATED WITH THE SERIES OF DISTURBANCES
ALOFT AND LOW LEVEL CONVERGENCE ALONG THE PRE-FRONTAL TROUGH/FRONT
WILL SUPPORT THE DEVELOPMENT OF NUMEROUS TO WIDESPREAD SHOWERS AND
STORMS TUE. THE SLOW SOUTHWARD PASSAGE OF THE SURFACE FRONT WILL END
THE THREAT OF CONVECTION FROM NORTH TO SOUTH TUE EVENING AND
OVERNIGHT...WITH JUST A LINGERING CHANCE OF A FEW SHOWERS ALONG THE
FAR SOUTHERN TIER BY WED MORNING.
WHILE WSW MEAN FLOW ALIGNED PARALLEL TO THE UNDERLYING SURFACE FRONT
SUGGESTS DOWNPOURS/ LOCALIZED FLOODING IN TRAINING STORMS ALONG THE
BOUNDARY MAY PROVIDE THE GREATEST IMPACT...INCREASING MID LEVEL
FLOW/BULK SHEAR TO AROUND 30 KTS MAY ALSO SUPPORT MULTI-CELL STORM
ORGANIZATION WITH PRECIPITATION-LOADED STRONG WET MICROBURST WIND
GUSTS. IN ADDITION...FORECAST MAXIMUM SRH AROUND 100 M2/S2 COULD BE
NEARLY DOUBLED LOCALLY INVOF OUTFLOW/BACKED SURFACE FLOW...WHICH
COULD SUPPORT BRIEF SUPERCELLULAR STRUCTURES...THOUGH SUCH A
SCENARIO WILL BE DEPENDENT ON MESO AND STORM SCALE INFLUENCES WITH
LIMITED PREDICTABILITY BEYOND A FEW HOURS. AS SUCH...WILL INCLUDE
ONLY A GENERIC ONE SENTENCE MENTION OF A STRONG TO SEVERE STORM IN
THE HWO FOR NOW FOR TUE. MOSTLY CLOUDY AND STORMY CONDITIONS WILL
SUPPORT HIGHS FROM THE UPPER 70S NW...TO LOWER TO MIDDLE 80S OVER
THE SOUTH...WITH LOWS MOSTLY IN THE UPPER 60S...TO AROUND 70 DEGREES
SOUTH.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 255 AM SUNDAY...
WEDNESDAY THROUGH SATURDAY: BELOW AVERAGE TEMPERATURES - IN THE
UPPER 70S TO LOWER-MIDDLE 80S - IN WEAK POST-FRONTAL HIGH PRESSURE
AND ASSOCIATED GENERALLY EAST TO ENE LOW LEVEL FLOW...WILL THEN
PREVAIL THROUGH THE END OF THE WEEK. HOWEVER...THE SURFACE FRONT
WILL LIKELY LINGER OVER SC THROUGH THU GIVEN CONTINUED FRONT-
PARALLEL FLOW ALOFT IN THE BASE OF BROAD EASTERN CONUS TROUGH. WILL
ACCORDINGLY MAINTAIN A SLIGHT CHANCE OF A SHOWER OR STORM OVER THE
FAR SOUTHERN SANDHILLS AND COASTAL PLAIN...IN CLOSEST PROXIMITY TO
THIS FRONT AND HIGHER BL MOISTURE...AND ALSO TOWARD THE YADKIN RIVER
WHERE A FEW WEAKENING SHOWERS/STORMS MAY DRIFT AFTER INITIATION AND
PROPAGATION FROM THE EASTERN SLOPES. A WARMER SOUTHEASTERLY...TO
SOUTHERLY RETURN FLOW BY SATURDAY...WILL RESULT IN RISING
TEMPERATURES TO AROUND THE 30-YEAR AVERAGE...AND HUMIDITY
LEVELS...BY THE WEEKEND. A RISK OF A FEW LATE AFTERNOON PULSE
SHOWERS OR STORMS WILL CONSEQUENTLY INCREASE TO NEAR CLIMATOLOGICAL
PROBABILITIES...AROUND 20 PERCENT OR SO...BY SAT.
&&
.AVIATION /14Z SUNDAY THROUGH FRIDAY/...
AS OF 930 AM SUNDAY...
VFR CONDITIONS WILL CONTINUE THROUGH THE TAF PERIOD. SOUTHWEST WINDS
WILL BE INCREASING AHEAD OF AN APPROACHING FRONT...WITH 10-12KTS
SUSTAINED TODAY WITH GUSTS TO 20-22KTS FROM LATE MORNING THROUGH THE
AFTERNOON. MID LEVEL FLOW WILL BECOME MORE WESTERLY AND ALTOCUMULUS
WILL CONTINUE TO BE ON THE INCREASE TONIGHT. A DISTURBANCE MOVING
INTO THE NORTHWEST WILL GRAZE ACROSS THE NORTHERN TIER OF THE
AREA...PRODUCING A CHANCE OF SHOWERS MAINLY IN THE GSO/INT VICINITY
AFTER 06Z.
IN THE LONGER RANGE...THE APPROACHING FRONT WILL STALL ACROSS THE
AREA LATER MONDAY THROUGH TUESDAY...WITH MVFR/IFR CONDITIONS AND
INCREASING COVERAGE OF SHOWERS/STORMS. VFR CONDITIONS WILL RETURN
BEHIND THE FRONT LATE TUESDAY NIGHT AND DOMINATE THROUGH FRIDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...KMC
NEAR TERM...DJF/MLM
SHORT TERM...MLM/MWS
LONG TERM...MWS
AVIATION...DJF/MLM
AREA FORECAST DISCUSSION
NWS RALEIGH NC
931 AM EDT SUN JUN 16 2013
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OVER OUR REGION TODAY. A COLD FRONT WILL
APPROACH FROM THE NORTHWEST MONDAY AND MOVE ACROSS OUR REGION LATE
TUESDAY INTO EARLY WEDNESDAY MORNING.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 930 AM SUNDAY...
THE UPPER RIDGE WILL CONTINUE TO FLATTEN TODAY AS SURFACE HIGH
PRESSURE CONTINUES TO MOVE OFF TO THE SOUTHEAST...AND THE GRADIENT
TIGHTENS BETWEEN THE RETREATING HIGH AND SURFACE TROUGHINESS
SHARPENING OVER THE WESTERN PART OF THE STATE. THE 12Z KGSO
SOUNDING...AS WELL AS THE SOUNDING FROM KMHX...SHOWED A DECENT CAP
REMAINING AROUND 700MB...WHILE THE KRNK SOUNDING INDICATED JUST
SLIGHTLY COOLER TEMPERATURES JUST ABOVE 700MB ALBEIT WITH A WEAK CAP
IN PLACE. THE RAP SOUNDINGS FORECAST THIS CAP ESSENTIALLY REMAINING
FOR THE REST OF THE DAY...VERY GRADUALLY DIMINISHING ESPECIALLY
TOWARD THE NORTHWEST PIEDMONT AS THE RIDGE FLATTENS...UPPER LEVELS
COOL...AND THE OVERALL MOISTURE OF THE AIR MASS INCREASES. THE RAP
FORECASTS 850MB SUBSIDENCE THROUGHOUT THE DAY...WITH ANY MODEST UVV
WITH APPROACHING MID-LEVEL SHORTWAVES HOLDING OFF UNTIL 00Z AND
AFTER. THE LATEST HRRR WRF IS DRY AS WELL...ALONG WITH QPF FROM THE
RAP. WILL CONTINUE WITH A DRY FORECAST TODAY...AND EXPECT PERIODS OF
MOSTLY MID- AND SOME HIGH-LEVEL CLOUDS TO RESULT IN A
PARTLY-TO-MOSTLY SUNNY LATE MORNING AND AFTERNOON. ALREADY THERE
HAVE BEEN A FEW WIND GUSTS IN THE TEENS KNOTS AND...BASED ON THE
LATEST RAP SOUNDINGS AND THE WINDS ALOFT ON THE KRAX 88D VAD WIND
PROFILE...INCREASED THE GUSTS A TRIFLE ESPECIALLY OUTSIDE OF
SOUTHEAST AREAS TO MORE AROUND 20KT. WHILE THE MAV MOS HAS SIMPLY
BEEN TOO WARM OF LATE...THE MET MOS IS CLOSER TODAY TO THE MAV AND
TO THE ONGOING FORECAST. LOWERED A DEGREE TOWARD KRWI BASED ON THE
LATEST TRENDS AND MOS...AND AS A RESULT OF SLIGHTLY COOLER
1000-850MB THICKNESSES COMPARED TO THE REST OF CENTRAL NORTH
CAROLINA. STILL...HIGHS 85 TO 90.
CLOUDINESS...AGAIN MAINLY MID AND UPPER...WILL BECOME PREVALENT
TONIGHT AS THE APPROACHING FRONT TRANSLATES INTO THE LEE TROUGH.
RAIN CHANCES ARE SMALL AND WILL BE MAINLY ACROSS THE NORTHERN TIER
WHICH WILL BE SKIRTED BY THE REMNANT OF A WEAKENING VORT MAX INDUCED
BY DEEP CONVECTION OVER THE OHIO VALLEY EARLY THIS MORNING. MINS
WILL BE MILD AND SEASONABLE...UPPER 60S.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 315 AM SUNDAY...
MONDAY AND MONDAY NIGHT...TRANSITION TO A BROAD LONGWAVE TROF WILL
BE UNDERWAY AND THE LINGERING LOW LEVEL TROFFING ALONG THE ATLANTIC
SEABOARD WILL PROMOTE AN INCREASINGLY MOIST AIRMASS. THICKNESSES ARE
RELATIVELY HIGH AND SIMILAR TO SUNDAY...WITH THE POTENTIAL FOR UPPER
80S. MOSTLY CLOUDY SKIES WILL HAMPER INSOLATION A BIT...MOSTLY MID
80S WEST TO UPPER 80S EAST. CHANCES OF SHOWERS WILL INCREASE MONDAY
AFTERNOON INTO MONDAY NIGHT IN INCREASINGLY DISTURBED FLOW...BUT ITS
DIFFICULT TO PICK OUT A PARTICULAR FEATURE DURING THIS TIME FRAME TO
FOCUS ACTIVITY...WILL CONTINUE CHANCE CATEGORY POPS FAVORING THE
WEST AND NORTH.
TUESDAY AND TUESDAY NIGHT: WITHIN A BROAD TROUGH ALOFT EAST OF THE
ROCKIES...A LOW AMPLITUDE SOUTHERN STREAM SHORTWAVE TROUGH...AND
PERHAPS A PRECEDING MCV FROM CONVECTION INITIATED AHEAD OF THIS WAVE
OVER THE CENTRAL PLAINS LATER TODAY AND TONIGHT...WILL MIGRATE
THROUGH THE BASE OF THE TROUGH/ACROSS THE CENTRAL APPALACHIANS AND
MIDDLE ATLANTIC REGION TUE. THESE FEATURES WILL BE FOLLOWED QUICKLY
BY AN ELONGATED BUT STRONGER NORTHERN STREAM WAVE IN NW FLOW FROM
THE UPPER MIDWEST TO THE CENTRAL APPALACHIANS TUE NIGHT.
IN THE LOW LEVELS...A PRE-FRONTAL TROUGH OVER VA/NC TUE WILL BE
OVERTAKEN BY A COLD FRONT ATTENDING THE AFOREMENTIONED NORTHERN
STREAM S/W TROUGH...AND THIS MERGED BOUNDARY WILL SETTLE SOUTHWARD
ACROSS CENTRAL NC TUE NIGHT. WITH A CONDITIONALLY UNSTABLE AND
UNCAPPED ENVIRONMENT PER BUFR SOUNDINGS...AND WITH FORECAST
PRECIPITABLE WATER VALUES APPROACHING TWO INCHES...THE WEAK (~20
METER/12 HR) HEIGHT FALLS ASSOCIATED WITH THE SERIES OF DISTURBANCES
ALOFT AND LOW LEVEL CONVERGENCE ALONG THE PRE-FRONTAL TROUGH/FRONT
WILL SUPPORT THE DEVELOPMENT OF NUMEROUS TO WIDESPREAD SHOWERS AND
STORMS TUE. THE SLOW SOUTHWARD PASSAGE OF THE SURFACE FRONT WILL END
THE THREAT OF CONVECTION FROM NORTH TO SOUTH TUE EVENING AND
OVERNIGHT...WITH JUST A LINGERING CHANCE OF A FEW SHOWERS ALONG THE
FAR SOUTHERN TIER BY WED MORNING.
WHILE WSW MEAN FLOW ALIGNED PARALLEL TO THE UNDERLYING SURFACE FRONT
SUGGESTS DOWNPOURS/ LOCALIZED FLOODING IN TRAINING STORMS ALONG THE
BOUNDARY MAY PROVIDE THE GREATEST IMPACT...INCREASING MID LEVEL
FLOW/BULK SHEAR TO AROUND 30 KTS MAY ALSO SUPPORT MULTI-CELL STORM
ORGANIZATION WITH PRECIPITATION-LOADED STRONG WET MICROBURST WIND
GUSTS. IN ADDITION...FORECAST MAXIMUM SRH AROUND 100 M2/S2 COULD BE
NEARLY DOUBLED LOCALLY INVOF OUTFLOW/BACKED SURFACE FLOW...WHICH
COULD SUPPORT BRIEF SUPERCELLULAR STRUCTURES...THOUGH SUCH A
SCENARIO WILL BE DEPENDENT ON MESO AND STORM SCALE INFLUENCES WITH
LIMITED PREDICTABILITY BEYOND A FEW HOURS. AS SUCH...WILL INCLUDE
ONLY A GENERIC ONE SENTENCE MENTION OF A STRONG TO SEVERE STORM IN
THE HWO FOR NOW FOR TUE. MOSTLY CLOUDY AND STORMY CONDITIONS WILL
SUPPORT HIGHS FROM THE UPPER 70S NW...TO LOWER TO MIDDLE 80S OVER
THE SOUTH...WITH LOWS MOSTLY IN THE UPPER 60S...TO AROUND 70 DEGREES
SOUTH.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 255 AM SUNDAY...
WEDNESDAY THROUGH SATURDAY: BELOW AVERAGE TEMPERATURES - IN THE
UPPER 70S TO LOWER-MIDDLE 80S - IN WEAK POST-FRONTAL HIGH PRESSURE
AND ASSOCIATED GENERALLY EAST TO ENE LOW LEVEL FLOW...WILL THEN
PREVAIL THROUGH THE END OF THE WEEK. HOWEVER...THE SURFACE FRONT
WILL LIKELY LINGER OVER SC THROUGH THU GIVEN CONTINUED FRONT-
PARALLEL FLOW ALOFT IN THE BASE OF BROAD EASTERN CONUS TROUGH. WILL
ACCORDINGLY MAINTAIN A SLIGHT CHANCE OF A SHOWER OR STORM OVER THE
FAR SOUTHERN SANDHILLS AND COASTAL PLAIN...IN CLOSEST PROXIMITY TO
THIS FRONT AND HIGHER BL MOISTURE...AND ALSO TOWARD THE YADKIN RIVER
WHERE A FEW WEAKENING SHOWERS/STORMS MAY DRIFT AFTER INITIATION AND
PROPAGATION FROM THE EASTERN SLOPES. A WARMER SOUTHEASTERLY...TO
SOUTHERLY RETURN FLOW BY SATURDAY...WILL RESULT IN RISING
TEMPERATURES TO AROUND THE 30-YEAR AVERAGE...AND HUMIDITY
LEVELS...BY THE WEEKEND. A RISK OF A FEW LATE AFTERNOON PULSE
SHOWERS OR STORMS WILL CONSEQUENTLY INCREASE TO NEAR CLIMATOLOGICAL
PROBABILITIES...AROUND 20 PERCENT OR SO...BY SAT.
&&
.AVIATION /14Z SUNDAY THROUGH FRIDAY/...
AS OF 930 AM SUNDAY...
VFR CONDITIONS WILL CONTINUE THROUGH THE TAF PERIOD. SOUTHWEST WINDS
WILL BE INCREASING AHEAD OF AN APPROACHING FRONT...WITH 10-12KTS
SUSTAINED TODAY WITH GUSTS TO 20-22KTS FROM LATE MORNING THROUGH THE
AFTERNOON. MID LEVEL FLOW WILL BECOME MORE WESTERLY AND ALTOCUMULUS
WILL CONTINUE TO BE ON THE INCREASE TONIGHT. A DISTURBANCE MOVING
INTO THE NORTHWEST WILL GRAZE ACROSS THE NORTHERN TIER OF THE
AREA...PRODUCING A CHANCE OF SHOWERS MAINLY IN THE GSO/INT VICINITY
AFTER 06Z.
IN THE LONGER RANGE...THE APPROACHING FRONT WILL STALL ACROSS THE
AREA LATER MONDAY THROUGH TUESDAY...WITH MVFR/IFR CONDITIONS AND
INCREASING COVERAGE OF SHOWERS/STORMS. VFR CONDITIONS WILL RETURN
BEHIND THE FRONT LATE TUESDAY NIGHT AND DOMINATE THROUGH FRIDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...KMC
NEAR TERM...DJF/MLM
SHORT TERM...MLM/MWS
LONG TERM...MWS
AVIATION...DJF/MLM
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1018 AM CDT SUN JUN 16 2013
.UPDATE...
ISSUED AT 1006 AM CDT SUN JUN 16 2013
UPPER LOW OVER SASKATCHEWAN OPENING UP AND MOVING SOUTHEAST AS
FORECAST. THIS WILL BRING CLOUDS INTO THE NORTH WITH SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS THIS AFTERNOON. MAIN CHANGES
THIS FORECAST ARE WINDS FOR THE JAMES RIVER VALLEY. UPPED WINDS TO
20 TO 35 MPH. STILL BELOW WIND ADVISORY CRITERIA BUT WILL WATCH.
UPDATE ISSUED AT 642 AM CDT SUN JUN 16 2013
CLEAR SKIES ACROSS WESTERN AND CENTRAL NORTH DAKOTA THIS MORNING
WITH CLOUDS ASSOCIATED WITH A LOW PRESSURE SYSTEM OVER SOUTHERN
SASKATCHEWAN STARTING TO INCH CLOSER TO THE NORTHERN TIER
COUNTIES. MINIMAL CHANGES TO THE GOING FORECAST THIS MORNING. DID
LOWER SKY COVER ACROSS THE NORTH THROUGH MID MORNING. ALSO DROPPED
THE MENTION OF THUNDER UNTIL AFTERNOON. LATEST 06Z GFS BUFR
SOUNDINGS FROM KISN AND KMOT INDICATE CONVECTION WILL BE HARD TO
DEVELOP BEFORE 18 UTC. WILL NEED TO MONITOR THE SOUTH FOR POSSIBLE
SHOWERS THIS AFTERNOON...BUT BETTER MOISTURE SHOULD REMAIN SOUTH
OF THE BORDER. LATEST 06 UTC NAM KEEPS ACTIVITY SOUTH OF THE
BORDER EXCEPT FOR MAYBE CLIPPING THE FAR SOUTHEAST CWA LATE THIS
AFTERNOON. THE 10Z RAP ALSO KEEPS ACTIVITY SOUTH OF THE BORDER.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 402 AM CDT SUN JUN 16 2013
MAIN FORECAST CONCERNS ARE WINDS TODAY AND PRECIP CHANCES/COVERAGE
THIS AFTERNOON AND EVENING.
WV IMAGERY CONTINUES TO SHOW UPPER LOW OVER CENTRAL SASKATCHEWAN
DRIFTING SOUTHWARD TOWARD NORTH DAKOTA. SATELLITE IMAGERY AND
SURFACE OBS SHOW EXTENSIVE AREA OF LOW CEILINGS IN CANADA
ASSOCIATED WITH THIS LOW. MOS GUIDANCE...MODEL RH FIELDS AND
FORECAST SOUNDINGS INDICATE SOME OF THESE LOW CEILINGS COULD
SPREAD INTO OUR CWA...MAINLY CENTRAL AND EASTERN PORTIONS LATE
SUNDAY NIGHT INTO MONDAY MORNING.
OTHERWISE...MODELS ARE IN DECENT AGREEMENT BRINGING SHOWER
ACTIVITY ACROSS CANADIAN BORDER BY AROUND 18Z AS UPPER LOW CLIPS
NORTHEASTERN ND. PRECIP AMOUNTS WITH ANY SHOWERS SHOULD BE ON THE
LIGHT SIDE AND CONVECTION SHOULD DIE OUT BY 06Z.
WITH REGARD TO WINDS TODAY...FORECAST SOUNDINGS/BUFKIT DATA LIMIT
WINDS IN THE MIXED LAYER AT MOST LOCATIONS TO 30 KTS...SO ANOTHER
BREEZY DAY EXPECTED BUT DO NOT SEE WIND ADVISORY CRITERIA BEING
MET.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 402 AM CDT SUN JUN 16 2013
NEAR NORMAL TEMPERATURES WILL HIGHLIGHT THE EXTENDED PERIOD WITH
A MORE ACTIVE PATTERN FOR THUNDERSTORMS POTENTIALLY BECOMING
ESTABLISHED WEDNESDAY NIGHT THROUGH SATURDAY.
THE 12 UTC GUIDANCE SUITE IS IN GOOD AGREEMENT THROUGH MOST OF THE
EXTENDED FORECAST PERIOD AND WILL USE A MODEL BLEND WITH PERSISTENCE
FOR MOST FIELDS. AN UPPER LEVEL RIDGE IS FORECAST TO MOVE INTO THE
CENTRAL U.S. MONDAY AND REMAIN THROUGH AT LEAST WEDNESDAY BEFORE
A SHIFT OF THE AXIS TO THE EAST WEDNESDAY NIGHT INTO NEXT
WEEKEND... WHICH WOULD YIELD SOUTHWEST FLOW ALOFT OVER THE
NORTHERN PLAINS. THIS UPPER LEVEL PATTERN SUPPORTS NEAR NORMAL
TEMPERATURES ACROSS WESTERN AND CENTRAL NORTH DAKOTA...WITH
THUNDERSTORM CHANCES INCREASING WEDNESDAY NIGHT THROUGH SATURDAY
WITH THE FORECAST TRANSITION TO A FAVORABLE SOUTHWEST FLOW ALOFT
WITH SEVERAL IMPULSES POTENTIALLY EJECTING OUT OF THE APPROACHING
UPPER LEVEL LOW. DIFFERENCES THAT DO CROP UP WITH THE PROGRESSION
OF THE UPPER LOW FROM THE NORTHERN ROCKIES INTO THE SOUTHERN
CANADIAN PRAIRIE PROVINCES LATE IN THE EXTENDED PERIOD WILL HAVE
LITTLE IMPACT ON THE RESULTING FORECAST THROUGH SATURDAY NIGHT AS
THE ACTIVE FLOW PATTERN WILL PERSIST EITHER WAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1006 AM CDT SUN JUN 16 2013
AT 10 AM CDT...SURFACE LOW PRESSURE OVER MANITOBA/SASKATCHEWAN
BORDER IS FORECAST TO MOVE SLOWLY SOUTHEAST. HIGH PRESSURE IN
MONTANA WILL REMAIN NEARLY STATIONARY. MAIN HAZARDS TO AVIATION
INCLUDE GUSTY SURFACE WINDS OF 20 TO 30 KTS. THINK MVFR CEILINGS
IN SOUTHERN SASKATCHEWAN SHOULD LIFT TO LOW VFR BY THE TIME THEY
DROP INTO NORTHERN TAF SITES OF KISN AND KMOT. WINDS WILL DIMINISH
EARLY THIS EVENING. WILL SEE INCREASING CLOUDS 15-18Z SUNDAY AS
AFTERNOON CU REGENERATE. BEST CHANCES OF PRECIPITATION SUNDAY
AFTERNOON WILL BE NORTH SO INCLUDED A VCSH FOR KMOT AND KISN.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...JNS
LONG TERM...TWH
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
643 AM CDT SUN JUN 16 2013
.UPDATE...
ISSUED AT 642 AM CDT SUN JUN 16 2013
CLEAR SKIES ACROSS WESTERN AND CENTRAL NORTH DAKOTA THIS MORNING
WITH CLOUDS ASSOCIATED WITH A LOW PRESSURE SYSTEM OVER SOUTHERN
SASKATCHEWAN STARTING TO INCH CLOSER TO THE NORTHERN TIER
COUNTIES. MINIMAL CHANGES TO THE GOING FORECAST THIS MORNING. DID
LOWER SKY COVER ACROSS THE NORTH THROUGH MID MORNING. ALSO DROPPED
THE MENTION OF THUNDER UNTIL AFTERNOON. LATEST 06Z GFS BUFR
SOUNDINGS FROM KISN AND KMOT INDICATE CONVECTION WILL BE HARD TO
DEVELOP BEFORE 18 UTC. WILL NEED TO MONITOR THE SOUTH FOR POSSIBLE
SHOWERS THIS AFTERNOON...BUT BETTER MOISTURE SHOULD REMAIN SOUTH
OF THE BORDER. LATEST 06 UTC NAM KEEPS ACTIVITY SOUTH OF THE
BORDER EXCEPT FOR MAYBE CLIPPING THE FAR SOUTHEAST CWA LATE THIS
AFTERNOON. THE 10Z RAP ALSO KEEPS ACTIVITY SOUTH OF THE BORDER.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 402 AM CDT SUN JUN 16 2013
MAIN FORECAST CONCERNS ARE WINDS TODAY AND PRECIP CHANCES/COVERAGE
THIS AFTERNOON AND EVENING.
WV IMAGERY CONTINUES TO SHOW UPPER LOW OVER CENTRAL SASKATCHEWAN
DRIFTING SOUTHWARD TOWARD NORTH DAKOTA. SATELLITE IMAGERY AND
SURFACE OBS SHOW EXTENSIVE AREA OF LOW CEILINGS IN CANADA
ASSOCIATED WITH THIS LOW. MOS GUIDANCE...MODEL RH FIELDS AND
FORECAST SOUNDINGS INDICATE SOME OF THESE LOW CEILINGS COULD
SPREAD INTO OUR CWA...MAINLY CENTRAL AND EASTERN PORTIONS LATE
SUNDAY NIGHT INTO MONDAY MORNING.
OTHERWISE...MODELS ARE IN DECENT AGREEMENT BRINGING SHOWER
ACTIVITY ACROSS CANADIAN BORDER BY AROUND 18Z AS UPPER LOW CLIPS
NORTHEASTERN ND. PRECIP AMOUNTS WITH ANY SHOWERS SHOULD BE ON THE
LIGHT SIDE AND CONVECTION SHOULD DIE OUT BY 06Z.
WITH REGARD TO WINDS TODAY...FORECAST SOUNDINGS/BUFKIT DATA LIMIT
WINDS IN THE MIXED LAYER AT MOST LOCATIONS TO 30 KTS...SO ANOTHER
BREEZY DAY EXPECTED BUT DO NOT SEE WIND ADVISORY CRITERIA BEING
MET.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 402 AM CDT SUN JUN 16 2013
NEAR NORMAL TEMPERATURES WILL HIGHLIGHT THE EXTENDED PERIOD WITH
A MORE ACTIVE PATTERN FOR THUNDERSTORMS POTENTIALLY BECOMING
ESTABLISHED WEDNESDAY NIGHT THROUGH SATURDAY.
THE 12 UTC GUIDANCE SUITE IS IN GOOD AGREEMENT THROUGH MOST OF THE
EXTENDED FORECAST PERIOD AND WILL USE A MODEL BLEND WITH PERSISTENCE
FOR MOST FIELDS. AN UPPER LEVEL RIDGE IS FORECAST TO MOVE INTO THE
CENTRAL U.S. MONDAY AND REMAIN THROUGH AT LEAST WEDNESDAY BEFORE
A SHIFT OF THE AXIS TO THE EAST WEDNESDAY NIGHT INTO NEXT
WEEKEND... WHICH WOULD YIELD SOUTHWEST FLOW ALOFT OVER THE
NORTHERN PLAINS. THIS UPPER LEVEL PATTERN SUPPORTS NEAR NORMAL
TEMPERATURES ACROSS WESTERN AND CENTRAL NORTH DAKOTA...WITH
THUNDERSTORM CHANCES INCREASING WEDNESDAY NIGHT THROUGH SATURDAY
WITH THE FORECAST TRANSITION TO A FAVORABLE SOUTHWEST FLOW ALOFT
WITH SEVERAL IMPULSES POTENTIALLY EJECTING OUT OF THE APPROACHING
UPPER LEVEL LOW. DIFFERENCES THAT DO CROP UP WITH THE PROGRESSION
OF THE UPPER LOW FROM THE NORTHERN ROCKIES INTO THE SOUTHERN
CANADIAN PRAIRIE PROVINCES LATE IN THE EXTENDED PERIOD WILL HAVE
LITTLE IMPACT ON THE RESULTING FORECAST THROUGH SATURDAY NIGHT AS
THE ACTIVE FLOW PATTERN WILL PERSIST EITHER WAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 642 AM CDT SUN JUN 16 2013
VFR CONDITIONS ALL TERMINALS THROUGH THE PERIOD. THINK MVFR
CEILINGS IN SOUTHERN SASKATCHEWAN SHOULD LIFT TO LOW VFR BY THE
TIME THEY DROP INTO NORTHERN TAF SITES OF KISN AND KMOT. WINDS
WILL INCREASE THIS MORNING WITH ANOTHER BREEZY DAY EXPECTED...
GENERALLY OUT OF THE WEST 20G30 KTS. WINDS WILL DIMINISH EARLY
THIS EVENING. WILL SEE INCREASING CLOUDS 15-18Z SUNDAY AS
AFTERNOON CU REGENERATE. BEST CHANCES OF PRECIPITATION SUNDAY
AFTERNOON WILL BE NORTH SO INCLUDED A VCSH FOR KMOT AND KISN. MAY
GET NEAR MVFR CIGS AT NORTH TERMINALS AS WELL SUNDAY 17-23Z.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...JNS
LONG TERM...TWH
AVIATION...JNS
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1120 AM EDT SUN JUN 16 2013
.SYNOPSIS...
MOISTURE INCREASES AS DISTURBANCES ALOFT HELP CAUSE ROUNDS OF
SHOWERS AND THUNDERSTORMS INTO TONIGHT. DEEPER MOISTURE SHUNTED
SOUTH MONDAY. ANOTHER STRONG SHORTWAVE PASSES TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
IN THE LATE MORNING UPDATE...ONE MID LEVEL DISTURBANCE DEPICTED ON
THE 13Z RAP MODEL FROM CMH TO CVG MOVES ACROSS NRN CNTRL WV AROUND
18/19Z AND WEAKENS. IN ITS WAKE...MORE MID LEVEL DISTURBANCES MOVE
UP THE OHIO RIVER REACHING HTS BY 21Z.
WILL BE FASTER INCREASING POPS THIS AFTERNOON AND THIS EVENING FOR
CENTRAL AND SOUTHERN COUNTIES. OTHER DISTURBANCES MAY FOLLOW FOR
SRN COUNTIES THROUGH ABOUT 06Z MONDAY. PRECIPITABLE WATER AROUND
1.5 TO 1.6 ON 12Z SOUNDINGS FROM ILN AND ILX. MODELS SHOW PWS
PEAKING TONIGHT AROUND 1.8 INCHES. OVERALL...ADDED A WATER CONCERN
FOR THE POSSIBILITY OF WEST TO EAST TRAINING DEVELOPING IN THIS
PATTERN. SO INCLUDED A WATER HAZARD MAINLY FOR THIS EVENING.
THINKING AT 14Z WAS THAT THIS THREAT WOULD SETTLE SOUTH WITH
TIME...SO BY OVERNIGHT...SOUTHERN HALF OF CWA MORE VULNERABLE THAN
THE NORTH.
OF COURSE...WILL HAVE TO JUST MONITOR RADAR...ON HOW THIS ALL
EXACTLY SETS UP AND UNFOLDS.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
A COLD FRONT CROSSES ACROSS THE OH RIVER BY 12-13Z MONDAY.
HOWEVER...LESS MOISTURE WILL BE AVAILABLE AS MODELS SUGGEST PW
AROUND 1.25 COULD LIMIT THE COVERAGE OF PCPN.
ANOTHER UPPER LEVEL DISTURBANCE CROSSES TUESDAY...CONTINUING WITH
LIKELY POPS NEARLY AREA WIDE THROUGH MUCH OF THE PERIOD. PW AROUND
1.6 INCHES...LESS THAN 25 KNOTS DEEP LAYER SHEAR AND SFC CAPE
VALUES EXCEEDING 2500 J/KG COULD RESULT IN SCATTERED TO NUMEROUS
SHOWERS AND THUNDERSTORMS TUESDAY AFTERNOON AND EVENING. AN ISOLATED
SEVERE STORM OR TWO CAN NOT BE RULED OUT.
ONLY MINIMAL CHANGES MADE TO TEMP FORECAST...CONTINUES TOO LOOK
FAIRLY SEASONABLE WITH HIGHS IN THE 70S ACROSS THE MOUNTAINS AND
80S IN THE LOWLANDS. LOWS SHOULD BE UPPER 50S AND 60S.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS UPPER RIDGE BEGINS TO BUILD TO THE WEST...SHOULD ONLY SEE
ISOLATED DIURNALLY DRIVEN POP UP THUNDERSHOWERS ACROSS THE
MOUNTAINOUS COUNTIES WEDNESDAY THROUGH FRIDAY AFTERNOONS. ACROSS
THE LOWLANDS...HIGH PRESSURE SHOULD KEEP THINGS DRY TO ROUND OUT
THE WORK WEEK. GFS/ECMWF BOTH SHOW A WARM FRONT LIFTING NORTH
SATURDAY AND INCLUDED CHANCE POPS WITH THAT.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
12Z SUNDAY THROUGH 12Z MONDAY...
VFR CONDITIONS ARE EXPECTED TO PREVAIL FOR MOST OF THE DAYLIGHT
HOURS AND INTO THE EARLY EVENING. HOWEVER...SHOWERS AND
THUNDERSTORMS CURRENTLY PUSHING INTO SE OHIO WILL CONTINUE TO
SPREAD EAST AND SOUTH AS THE DAY PROGRESSES. STILL...THE GREATER
GENERAL COVERAGE OF PRECIP SHOULD REMAIN NORTH OF A CRW-HTS LINE.
CIGS SHOULD REMAIN LOW VFR WITH THIS ACTIVITY...BUT AS ALWAYS
BRIEF MVFR CIGS AND MVFR/IFR VIS IS POSSIBLE UNDER STRONGER
SHOWERS AND THUNDERSTORMS. BY AROUND 06Z AND AFTER...THE POTENTIAL
FOR MVFR CIGS WILL INCREASE TOWARDS DAWN.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z MONDAY...
FORECAST CONFIDENCE...MEDIUM.
ALTERNATE SCENARIOS: TIMING OF CONVECTION AND ACCOMPANYING SUB-VFR
CONDITIONS MAY VARY FROM CURRENT FORECAST.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
EDT 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H M M M M M H
PKB CONSISTENCY H M M M M M M M M M M H
CKB CONSISTENCY H H H H H M M M M M M M
AFTER 12Z MONDAY...
IFR POSSIBLE MONDAY IN SHOWERS AND STORMS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...MZ
NEAR TERM...KTB
SHORT TERM...ARJ
LONG TERM...MZ
AVIATION...50
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1003 AM EDT SUN JUN 16 2013
.SYNOPSIS...
MOISTURE INCREASES AS DISTURBANCES ALOFT HELP CAUSE ROUNDS OF
SHOWERS AND THUNDERSTORMS INTO TONIGHT. DEEPER MOISTURE SHUNTED
SOUTH MONDAY. ANOTHER STRONG SHORTWAVE PASSES TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
IN THE LATE MORNING UPDATE...ONE MID LEVEL DISTURBANCE DEPICTED ON
THE 13Z RAP MODEL FROM CMH TO CVG MOVES ACROSS NRN CNTRL WV AROUND
18/19Z AND WEAKENS. IN ITS WAKE...MORE MID LEVEL DISTURBANCES MOVE
UP THE OHIO RIVER REACHING HTS BY 21Z.
WILL BE FASTER INCREASING POPS THIS AFTERNOON AND THIS EVENING FOR
SOUTHERN COUNTIES. OTHER DISTURBANCES MAY FOLLOW FOR SRN COUNTIES
THROUGH ABOUT 06Z MONDAY. PRECIPITABLE WATER AROUND 1.5 TO 1.6 ON
12Z SOUNDINGS FROM ILN AND ILX. MODELS SHOULD PW(S) PEAKING TONIGHT
AROUND 1.8 INCHES. OVERALL...ADDED A WATER CONCERN FOR THE
POSSIBILITY OF WEST TO EAST TRAINING DEVELOPING IN THIS PATTERN.
SO INCLUDED A WATER HAZARD MAINLY FOR THIS EVENING. THINKING AT 14Z
WAS THIS THREAT WOULD SETTLE SOUTH WITH TIME...SO BY
OVERNIGHT...SOUTHERN HALF OF CWA MORE VULNERABLE THAN THE NORTH.
OF COURSE...WILL HAVE TO JUST MONITOR RADAR...ON HOW THIS ALL
EXACTLY SETS UP AND UNFOLDS.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
A COLD FRONT CROSSES ACROSS THE OH RIVER BY 12-13Z MONDAY.
HOWEVER...LESS MOISTURE WILL BE AVAILABLE AS MODELS SUGGEST PW
AROUND 1.25 COULD LIMIT THE COVERAGE OF PCPN.
ANOTHER UPPER LEVEL DISTURBANCE CROSSES TUESDAY...CONTINUING WITH
LIKELY POPS NEARLY AREA WIDE THROUGH MUCH OF THE PERIOD. PW AROUND
1.6 INCHES...LESS THAN 25 KNOTS DEEP LAYER SHEAR AND SFC CAPE
VALUES EXCEEDING 2500 J/KG COULD RESULT IN SCATTERED TO NUMEROUS
SHOWERS AND THUNDERSTORMS TUESDAY AFTERNOON AND EVENING. AN ISOLATED
SEVERE STORM OR TWO CAN NOT BE RULED OUT.
ONLY MINIMAL CHANGES MADE TO TEMP FORECAST...CONTINUES TOO LOOK
FAIRLY SEASONABLE WITH HIGHS IN THE 70S ACROSS THE MOUNTAINS AND
80S IN THE LOWLANDS. LOWS SHOULD BE UPPER 50S AND 60S.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS UPPER RIDGE BEGINS TO BUILD TO THE WEST...SHOULD ONLY SEE
ISOLATED DIURNALLY DRIVEN POP UP THUNDERSHOWERS ACROSS THE
MOUNTAINOUS COUNTIES WEDNESDAY THROUGH FRIDAY AFTERNOONS. ACROSS
THE LOWLANDS...HIGH PRESSURE SHOULD KEEP THINGS DRY TO ROUND OUT
THE WORK WEEK. GFS/ECMWF BOTH SHOW A WARM FRONT LIFTING NORTH
SATURDAY AND INCLUDED CHANCE POPS WITH THAT.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
12Z SUNDAY THROUGH 12Z MONDAY...
VFR CONDITIONS ARE EXPECTED TO PREVAIL FOR MOST OF THE DAYLIGHT
HOURS AND INTO THE EARLY EVENING. HOWEVER...SHOWERS AND
THUNDERSTORMS CURRENTLY PUSHING INTO SE OHIO WILL CONTINUE TO
SPREAD EAST AND SOUTH AS THE DAY PROGRESSES. STILL...THE GREATER
GENERAL COVERAGE OF PRECIP SHOULD REMAIN NORTH OF A CRW-HTS LINE.
CIGS SHOULD REMAIN LOW VFR WITH THIS ACTIVITY...BUT AS ALWAYS
BRIEF MVFR CIGS AND MVFR/IFR VIS IS POSSIBLE UNDER STRONGER
SHOWERS AND THUNDERSTORMS. BY AROUND 06Z AND AFTER...THE POTENTIAL
FOR MVFR CIGS WILL INCREASE TOWARDS DAWN.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z MONDAY...
FORECAST CONFIDENCE...MEDIUM.
ALTERNATE SCENARIOS: TIMING OF CONVECTION AND ACCOMPANYING SUB-VFR
CONDITIONS MAY VARY FROM CURRENT FORECAST.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
EDT 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H M M M M M H
PKB CONSISTENCY H M M M M M M M M M M H
CKB CONSISTENCY H H H H H M M M M M M M
AFTER 12Z MONDAY...
IFR POSSIBLE MONDAY IN SHOWERS AND STORMS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...MZ
NEAR TERM...KTB
SHORT TERM...ARJ
LONG TERM...MZ
AVIATION...50
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
932 AM EDT SUN JUN 16 2013
.SYNOPSIS...
LOW PRESSURE FROM THE UPPER MIDWEST WILL MOVE ACROSS THE GREAT
LAKES ON TODAY AND DRAG A WEAK COLD FRONT ACROSS THE REGION. A
STRONGER COLD FRONT FROM CANADA WILL DROP ACROSS THE LOWER GREAT
LAKES MONDAY NIGHT. HIGH PRESSURE FROM CANADA WILL BUILD SOUTH
ACROSS THE GREAT LAKES BY MID WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
JUST SOME SCATTERED SHOWERS AT THE MOMENT. EXPECT A GRADUAL
DECREASE IN THIS ACTIVITY THE REMAINDER OF THE MORNING. MODELS
CONTINUE TO SUGGEST NEW DEVELOPMENT THIS AFTERNOON AS A WEAK
TROUGH SLIDES EAST ACROSS THE REGION. LATEST HRRR HAS MOST OF THIS
ACTIVITY OVER THE SE 1/2 OF THE AREA WHICH SEEMS REASONABLE. HAVE
ADJUSTED PRECIP CHANCES AS NEEDED. NO CHANGES TO TEMPS FOR NOW BUT
WILL TAKE ANOTHER LOOK IN A COUPLE OF HOURS. SUSPECT BY MID
AFTERNOON THAT MOST OF THE PRECIP WILL BE ALONG AND SOUTH OF THE
U.S. 30 CORRIDOR.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
THIS EVENING THE SLOW MOVING COLD FRONT WILL STILL BE ACROSS THE
AREA SO EARLY ON WILL NEED TO HOLD ONTO CHANCE POPS SE. AFTER
MIDNIGHT HOWEVER DROPPED THE MENTION OF PRECIP AS DRIER MORE
STABLE AIR MOVES IN. THIS WILL BE SHORT LIVED HOWEVER AS ANOTHER
LOW DROPS ACROSS THE CENTRAL GREAT LAKES ON MONDAY. MODELS BRING
THE COLD FRONT SOUTH ACROSS THE LAKES TO THE VICINITY BY 00Z
TUESDAY. MODELS ALSO BRING MORE MOISTURE INTO THE AREA DURING THE
DAY MONDAY. WILL BEGIN MONDAY DRY BUT WITH THE APPROACHING
SYSTEM...WILL HAVE CHANCE POPS NORTH AND SLIGHT CHANCE SOUTH FOR
THE AFTERNOON. MONDAY EVENING THE FRONT WILL DROP ACROSS THE AREA.
BY TUESDAY MORNING THE MODELS BEGIN TO DIVERGE WITH THE NAM
DEVELOPING A SURFACE LOW ACROSS NORTHERN OHIO AND DEEP MOISTURE
ACROSS THE REGION. THE GFS AND SREF ARE MORE SIMILAR BUILDING
DRIER AIR SOUTH ACROSS THE LAKES TO OUR NORTHERN BORDER WHILE
KEEPING ANY SURFACE LOW AND THE DEEP MOISTURE WELL SOUTH OF THE
AREA. WILL SIDE WITH THE SREF/GFS HERE. WILL HAVE CHANCE POPS
MONDAY NIGHT AND TUESDAY MORNING WITH THE FRONT...TAPERING FROM
THE NORTH/NORTHWEST TUESDAY AFTERNOON. HIGH PRESSURE BUILDS IN
TUESDAY NIGHT AND WEDNESDAY SO DRY AND A FEW DEGREES BELOW NORMAL
FOR MID WEEK.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
OVERALL CENTRAL U.S. RIDGE IS EXPECTED TO SHIFT EAST FROM THURSDAY
THROUGH SATURDAY WHILE FLATTENING TO SOME DEGREE. THERE ARE
SIGNIFICANT ENOUGH DIFFERENCES IN THE MODELS TO NOT MAKE ANY MAJOR
CHANGES TO THE CURRENT FORECAST. THE GFS IS STRONGER WITH THE RIDGE
AND THEREFORE WARMER AND DRIER. THE ECMWF ON THE OTHER HAND FLATTENS
THE RIDGE MORE AND ALLOWS SOME SHORTWAVE ENERGY TO TOP THE RIDGE AND
MOVE ACROSS THE GREAT LAKES. THIS WOULD BRING WITH IT SHRA/TS AND
LIKELY COOLER TEMPS DEPENDING ON CLOUD COVER. ALL IN ALL
TEMPERATURES WILL BE SEASONABLE...BUT MAY GET WARM IF WE TREND
TOWARD THE GFS WHICH IS RUNNING A COUPLE DEGREES WARMER AT H8. WHILE
THURSDAY WILL BE DRY...SLOWLY BRING UP PRECIP CHANCES AND CLOUD
COVER GOING INTO THE WEEKEND WITH THE INCREASED MOISTURE AND
POSSIBLE BOUNDARIES IN THE AREA.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
WARM FRONT CROSSING THE AREA EARLY THIS MORNING WILL BE FOLLOWED
BY THE COLD FRONT THIS AFTERNOON. INITIAL ROUND OF SHOWERS EARLY
THIS MORNING WERE/ARE ASSOCIATED WITH THE WARM FRONT. COULD VERY
WELL SEE NEW SHOWER DEVELOPMENT WITH THE COLD FRONT AND/OR A
PROLONGING OF SHOWERS ACROSS THE SOUTH. TOLEDO MAY BE IN THE CLEAR
ALREADY. THUNDER CHANCES UNCERTAIN...THERE IS QUITE A BIT OF CLOUD
COVER AND INSTABILITY MAY BE LIMITED AND FRONT IS WEAKENING.
CEILINGS...EVEN WITHIN THE EARLY MORNING SHOWERS WERE LARGELY VFR.
STILL WOULD THINK THAT WITH THE INCREASED LOW LEVEL MOISTURE WE
SHOULD DEVELOP A MVFR DECK THIS MORNING...LIFTING BACK TO VFR
LATER TODAY. WEST WIND...GUSTING AROUND 20 KNOTS WILL BRING IN
DRIER AIR AND IMPROVING CONDITIONS FROM WEST TO EAST DURING THE
AFTERNOON. HIGH PRESSURE BEGINS TO MOVE IN SUNDAY NIGHT. MAY HAVE
SOME FG/BR TO DEAL WITH MONDAY MORNING.
.OUTLOOK...NON VFR POSSIBLE MONDAY NIGHT INTO TUESDAY WITH A
FRONTAL PASSAGE.
&&
.MARINE...
LOW PRESSURE CROSSING NORTHERN LAKE MICHIGAN EARLY THIS MORNING IS
EXPECTED TO DEEPEN A LITTLE FURTHER AS IT SHIFTS EAST ACROSS ONTARIO
CANADA. IT WILL BRING SHOWERS/THUNDERSTORMS TO THE LAKE TODAY WITH
THE COLD FRONT CROSSING BY THIS AFTERNOON. THERE IS A LITTLE BIT OF
WIND WITH THIS SYSTEM. FEEL THERE IS ENOUGH TO GENERATE SOME 4 FOOT
WAVES ACROSS THE EAST END WITH THE WEST-SOUTHWEST FLOW. WILL HOLD
BACK ON A SMALL CRAFT ADV...BUT WILL MONITOR FOR
DEVELOPMENTS/CHANGES. NEXT FRONT ON THE HEELS OF TODAY/S AND WILL
CROSS THE LAKE 24-30 HOURS LATER...MONDAY LATE AFTERNOON. HIGH
PRESSURE WILL OVERSPREAD THE CENTRAL GREAT LAKES AND A
NORTH-NORTHEAST FLOW WILL BE REALIZED ON LAKE ERIE FOR TUESDAY INTO
WEDNESDAY. HIGH PRESSURE OVERHEAD WED-THU.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TK
NEAR TERM...KUBINA
SHORT TERM...TK
LONG TERM...OUDEMAN
AVIATION...OUDEMAN
MARINE...OUDEMAN
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1053 AM CDT SUN JUN 16 2013
.UPDATE...
WEAK FLOW ALOFT CONTINUES ACROSS NORTH TEXAS THIS MORNING WITH
UPPER HIGH EXPANDING WESTWARD ACROSS SOUTH TEXAS. BEST MOISTURE
PER GOES SATELLITE PWAT IMAGERY IS ACROSS NORTHERN/WESTERN PARTS
OF THE AREA. ACCAS SEEN OUTSIDE INDICATE SOME INSTABILITY ALOFT
AND A FEW SHOWERS HAVE DEVELOPED ACROSS THE WESTERN COUNTIES. THE
HIGH-RES HRRR/RAP AND TECH WRF TO A LESSER EXTENT ARE THE ONLY
MODELS CLOSE TO ANY REALITY IN THIS WEAK FLOW SITUATION TODAY.
WILL ADJUST POPS FOR LOW CHANCES ACROSS MAINLY THESE NORTHERN AND
WESTERN COUNTIES TODAY. WILL CONTINUE SLIGHTLY HIGHER CHANCES
ACROSS OUR FAR NORTHEAST COUNTIES LATE TODAY THROUGH SUNSET ONCE
AGAIN...AS SHORTWAVE MOVING FROM THE OK/TX PANHANDLES TRANSVERSES
EAST WITH TIME. SOME RESIDUAL OUTFLOW BOUNDARIES MAY ALSO PLAY A
ROLE ACROSS THE NORTHEAST. SIMILAR TO YESTERDAY...ENOUGH INSTABILITY
WILL EXIST FOR A STRONG STORM OR TWO WITH FREQUENT LIGHTNING...GUSTY
WINDS...AND LOCALIZED BRIEF HEAVY DOWNPOURS. FOR THOSE PLANNING
OUTDOOR EVENTS FATHERS DAY WILL NEED TO PAY ATTENTION THIS AFTERNOON
ALONG AND NORTH OF I-20/I-30.
DID LOWER HIGHS SOME OUT WEST FROM THE PREVIOUS FORECAST...WITH
CURRENT MID LEVEL CLOUD DECK AND ISOLATED SHOWERS EXPECTED INTO
THE EARLY AFTERNOON HOURS.
05/
&&
.AVIATION...
TAF PERIOD SHOULD BE RELATIVELY QUIET...ALTHOUGH CANT COMPLETELY
RULE OUT A STRAY SHOWER OR THUNDERSTORM. BEST CHANCES FOR RAIN
WILL BE BEYOND THIS TAF CYCLE...AFTER 00Z TUESDAY. SCT/BKN MID AND
HIGH CLOUDS WILL BE AROUND TODAY AND SOUTHERLY WINDS AROUND 10
KNOTS CAN BE EXPECTED.
HAMPSHIRE
&&
.PREV DISCUSSION... /ISSUED 329 AM CDT SUN JUN 16 2013/
THE FORECAST ESSENTIALLY BREAKS DOWN INTO TWO PARTS...THE SEMI-
WET PERIOD FOR THE NEXT FEW DAYS...AND THE DRY AND WARM/HOT
PERIOD FOR LATE WEEK INTO THE WEEKEND.
ALTHOUGH THE MAIN TROUGH IS MOVING EASTWARD THIS MORNING...A WEAK
DISTURBANCE MAY STILL BRING ANOTHER CHANCE OF SHOWERS
THUNDERSTORMS TODAY. THE HIGH RESOLUTION RAPID REFRESH IS THE
MOST AGGRESSIVE IN GENERATING ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS THROUGH THIS AFTERNOON. THE NAM AND TEXAS TECH WRF
ON THE OTHER HAND SHOW LITTLE IF ANY PRECIPITATION TODAY. IT
APPEARS THAT THE HRRR MAY BE TOO AGGRESSIVE...SO HAVE JUST GONE
WITH 20 PERCENT POPS ACROSS ALL BUT THE EXTREME WESTERN ZONES FOR
TODAY WHERE HAVE PLACED 10 PERCENT POPS AND THE NORTHEAST WHERE
THERE ARE 30 PERCENT POPS FOR THIS AFTERNOON. THIS SEEMS TO BE
CLOSER TO WHAT THE GFS/ECMWF/CANADIAN ARE INDICATING. AS A
STRONGER SHORTWAVE SLIDES ACROSS THE CENTRAL PLAINS
TONIGHT...MOST OF THE RAIN WILL BE TO THE NORTH OF THE FORECAST
AREA BUT HAVE KEPT SOME 20 PERCENT POPS ALONG AND NORTH OF A
GRAHAM TO SULPHUR SPRINGS LINE. THERE IS PRETTY GOOD AGREEMENT
BETWEEN THE GFS...ECWMF...CANADIAN AND TO A LESSER DEGREE THE
NAM...THAT THAT A COUPLE OF SHORTWAVES MOVING ACROSS CENTRAL AND
SOUTHERN PLAINS WILL DRIVE A COLD FRONT INTO NORTH TEXAS MONDAY
NIGHT...AND STALL IT NEAR OR SOUTH OF THE I-20 CORRIDOR TUESDAY.
THE FRONT WILL THEN LIFT BACK TO THE NORTH ON WEDNESDAY. THE BEST
RAIN CHANCES WILL BE NEAR AND NORTH OF THIS FRONT...SO HAVE
PLACED 30-40 PERCENT POPS ACROSS THE NORTH...WITH ONLY 20 PERCENT
ACROSS THE SOUTH.
RAIN CHANCES WILL END LATE WEDNESDAY AS AN UPPER RIDGE STARTS TO
BUILD INTO THE SOUTHERN PLAINS IN THE WAKE OF THE UPPER TROUGH
MOVING EASTWARD AND AN INTENSE UPPER LEVEL STORM MOVING INTO THE
PACIFIC NORTHWEST. THE RIDGE WILL TAKE RESIDENCE OVER THE SOUTHERN
PLAINS LATE WEEK INTO THE WEEKEND...BRINGING ABOVE NORMAL HIGH
TEMPERATURES WITH NO SIGNIFICANT CHANCE OF RAIN.
58
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 94 76 93 73 87 / 20 10 20 40 30
WACO, TX 96 75 95 74 92 / 10 10 10 20 20
PARIS, TX 92 73 90 71 85 / 30 20 30 40 30
DENTON, TX 92 75 91 72 86 / 20 20 20 40 30
MCKINNEY, TX 92 74 92 71 86 / 20 20 20 40 30
DALLAS, TX 95 76 94 74 89 / 20 10 20 40 30
TERRELL, TX 94 74 93 73 89 / 20 10 20 30 30
CORSICANA, TX 95 74 94 73 91 / 10 10 10 20 20
TEMPLE, TX 96 74 93 72 93 / 10 10 10 20 20
MINERAL WELLS, TX 93 74 93 72 87 / 20 10 20 40 30
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
85/05
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
624 AM CDT SUN JUN 16 2013
.AVIATION...
TAF PERIOD SHOULD BE RELATIVELY QUIET...ALTHOUGH CANT COMPLETELY
RULE OUT A STRAY SHOWER OR THUNDERSTORM. BEST CHANCES FOR RAIN
WILL BE BEYOND THIS TAF CYCLE...AFTER 00Z TUESDAY. SCT/BKN MID AND
HIGH CLOUDS WILL BE AROUND TODAY AND SOUTHERLY WINDS AROUND 10
KNOTS CAN BE EXPECTED.
HAMPSHIRE
&&
.PREV DISCUSSION... /ISSUED 329 AM CDT SUN JUN 16 2013/
THE FORECAST ESSENTIALLY BREAKS DOWN INTO TWO PARTS...THE SEMI-
WET PERIOD FOR THE NEXT FEW DAYS...AND THE DRY AND WARM/HOT
PERIOD FOR LATE WEEK INTO THE WEEKEND.
ALTHOUGH THE MAIN TROUGH IS MOVING EASTWARD THIS MORNING...A WEAK
DISTURBANCE MAY STILL BRING ANOTHER CHANCE OF SHOWERS
THUNDERSTORMS TODAY. THE HIGH RESOLUTION RAPID REFRESH IS THE
MOST AGGRESSIVE IN GENERATING ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS THROUGH THIS AFTERNOON. THE NAM AND TEXAS TECH WRF
ON THE OTHER HAND SHOW LITTLE IF ANY PRECIPITATION TODAY. IT
APPEARS THAT THE HRRR MAY BE TOO AGGRESSIVE...SO HAVE JUST GONE
WITH 20 PERCENT POPS ACROSS ALL BUT THE EXTREME WESTERN ZONES FOR
TODAY WHERE HAVE PLACED 10 PERCENT POPS AND THE NORTHEAST WHERE
THERE ARE 30 PERCENT POPS FOR THIS AFTERNOON. THIS SEEMS TO BE
CLOSER TO WHAT THE GFS/ECMWF/CANADIAN ARE INDICATING. AS A
STRONGER SHORTWAVE SLIDES ACROSS THE CENTRAL PLAINS
TONIGHT...MOST OF THE RAIN WILL BE TO THE NORTH OF THE FORECAST
AREA BUT HAVE KEPT SOME 20 PERCENT POPS ALONG AND NORTH OF A
GRAHAM TO SULPHUR SPRINGS LINE. THERE IS PRETTY GOOD AGREEMENT
BETWEEN THE GFS...ECWMF...CANADIAN AND TO A LESSER DEGREE THE
NAM...THAT THAT A COUPLE OF SHORTWAVES MOVING ACROSS CENTRAL AND
SOUTHERN PLAINS WILL DRIVE A COLD FRONT INTO NORTH TEXAS MONDAY
NIGHT...AND STALL IT NEAR OR SOUTH OF THE I-20 CORRIDOR TUESDAY.
THE FRONT WILL THEN LIFT BACK TO THE NORTH ON WEDNESDAY. THE BEST
RAIN CHANCES WILL BE NEAR AND NORTH OF THIS FRONT...SO HAVE
PLACED 30-40 PERCENT POPS ACROSS THE NORTH...WITH ONLY 20 PERCENT
ACROSS THE SOUTH.
RAIN CHANCES WILL END LATE WEDNESDAY AS AN UPPER RIDGE STARTS TO
BUILD INTO THE SOUTHERN PLAINS IN THE WAKE OF THE UPPER TROUGH
MOVING EASTWARD AND AN INTENSE UPPER LEVEL STORM MOVING INTO THE
PACIFIC NORTHWEST. THE RIDGE WILL TAKE RESIDENCE OVER THE SOUTHERN
PLAINS LATE WEEK INTO THE WEEKEND...BRINGING ABOVE NORMAL HIGH
TEMPERATURES WITH NO SIGNIFICANT CHANCE OF RAIN.
58
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 93 76 93 73 87 / 20 10 20 40 30
WACO, TX 94 75 95 74 92 / 20 10 10 20 20
PARIS, TX 92 73 90 71 85 / 30 20 30 40 30
DENTON, TX 92 75 91 72 86 / 20 20 20 40 30
MCKINNEY, TX 92 74 92 71 86 / 20 20 20 40 30
DALLAS, TX 95 76 94 74 89 / 20 10 20 40 30
TERRELL, TX 94 74 93 73 89 / 20 10 20 30 30
CORSICANA, TX 94 74 94 73 91 / 20 10 10 20 20
TEMPLE, TX 93 74 93 72 93 / 20 10 10 20 20
MINERAL WELLS, TX 94 74 93 72 87 / 20 10 20 40 30
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
625 AM CDT SUN JUN 16 2013
.UPDATE...
ISSUED AT 348 AM CDT SUN JUN 16 2013
HAVE EXPANDED THE DENSE FOG ADVISORY TO INCLUDE MUCH MORE OF
SOUTHWEST WISCONSIN AS WELL AS WINONA AND HOUSTON COUNTIES OF
MINNESOTA. CALLS TO COUNTY LAW ENFORCEMENTS AS WELL AS AUTOMATED
SURFACE OBSERVATIONS ARE SHOWING A LOT MORE VISIBILITIES OF 1/4
MILE OR LESS...INCLUDING VIROQUA...LA CROSSE...BLACK RIVER FALLS AND
WINONA. MOST RIVER VALLEYS OVER THE NORTHERN HALF OF THE FORECAST
AREA ARE ASSUMED TO BE SOCKED IN WITH FOG GIVEN THE CONDITIONS IN THE
MISSISSIPPI RIVER VALLEY. EXPECT ALL FOG TO DISSIPATE BY 9 AM WITH
THE EARLY SUNRISE HELPING TO MIX IT OUT QUICKLY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 307 AM CDT SUN JUN 16 2013
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED AN UPPER LOW OFF THE PACIFIC NORTHWEST COAST...AND NEARLY
ZONAL FLOW ACROSS MUCH OF THE NORTHERN U.S.. WITHIN THE ZONAL
FLOW...A COLLECTION OF SHORTWAVES...SOME CONVECTIVELY INDUCED...
EXTENDED FROM LOWER MICHIGAN INTO ARKANSAS. THESE SHORTWAVES HELPED
PRODUCE SOME OF THE CONVECTION YESTERDAY AFTERNOON AND EVENING. DRY
AIR HAS ADVECTED INTO THE FORECAST AREA BEHIND THE SHORTWAVES...
NOTED ON WATER VAPOR AS WELL AS THE 00Z MPX SOUNDING WHERE THE
PRECIPITABLE WATER HAS FALLEN TO 0.94 INCHES. FARTHER WEST...THE AIR
GETS EVEN DRIER...WITH THE 00Z ABR SOUNDING AT 0.34 INCHES FOR
PRECIPITABLE WATER. THE DRY AIR HAS EFFECTIVELY CLEARED MUCH OF THE
SKIES OUT. LIGHT WINDS...THE DRY AIR ALOFT AND PRECIPITATION LAST
EVENING HAS LED TO SOME FOG DEVELOPMENT... ESPECIALLY NORTH OF THE
I-94 CORRIDOR AS WELL AS IN THE MS RIVER VALLEY NORTH OF PRAIRIE DU
CHIEN. 850MB TEMPS DID NOT DROP MUCH WITH THE SHORTWAVE PASSAGE...
WITH READINGS GENERALLY 14-17C FROM THE DAKOTAS EAST INTO WISCONSIN.
MEANWHILE...TO THE NORTHWEST...AN UPPER LOW WAS SITTING OVER
SOUTHEAST SASKATCHEWAN. SOME CONVECTION FORMED AHEAD OF THE UPPER
LOW ALONG THE CANADIAN BORDER WITH NORTH DAKOTA AND MN DURING THE
DAYTIME HOURS YESTERDAY. THIS HAS SINCE MOSTLY DISSIPATED.
MAIN FOCUS IS ON THE UPPER LOW IN SOUTHEAST SASKATCHEWAN. MODELS
CONTINUE TO SHOW THE LOW DROPPING SOUTHEASTWARD AS IT BEGINS TO GET
CAUGHT UP IN THE CIRCULATION AROUND TROUGHING IN EASTERN CANADA. AT
THE SAME TIME...THE UPPER LOW IS PROGGED TO SHEAR OUT INTO A
SHORTWAVE. THERE ARE MODEL DIFFERENCES IN HOW FAR SOUTH THE
SHORTWAVE GETS TO AT 12Z MONDAY...RANGING FROM NEAR MINNEAPOLIS FROM
THE 16.00Z GFS TO NEAR BRAINERD MN FROM THE 16.00Z
NAM/UKMET/CANADIAN. THIS DIFFERENCE HAS IMPLICATIONS ON TIMING OF
POTENTIAL PRECIPITATION LATER TONIGHT.
TODAY CONTINUES TO LOOK QUIET AS WEST-NORTHWEST FLOW AHEAD OF THE
APPROACHING UPPER LOW/SHORTWAVE HELPS TO BRING THAT DRIER AIR IN
SEEN ON THE 00Z ABR SOUNDING. ANY CONVECTIVE ACTIVITY AHEAD OF THE
UPPER LOW/SHORTWAVE LIKE SEEN YESTERDAY AFTERNOON AND EVENING WILL
STAY NORTH AND WEST OF THE AREA. WE SHOULD SEE PLENTY OF
SUNSHINE...EASILY ALLOWING MIXING TO 850MB WHERE TEMPS OF 13-14C
WILL ALLOW FOR HIGHS IN THE LOW TO MID 80S. EXPECT ANY FOG THIS
MORNING TO QUICKLY DISSIPATE...LIKELY BY 9 AM OR EVEN EARLIER
GIVEN THE EARLY SUNRISE.
FOR TONIGHT...GOOD AGREEMENT EXISTS AMONGST MODELS THAT A SURGE OF
SOMEWHAT HIGHER PRECIPITABLE WATER WILL ADVECT INTO THE FORECAST
AREA AS THE UPPER LOW/SHORTWAVE DROPS INTO MN. VALUES CLIMB UP TO
AROUND 1 INCH. AT THE SAME TIME...THERE IS A DEFINITE SURGE OF 850MB
MOISTURE TRANSPORT TO HELP SUPPORT PRECIPITATION. BETWEEN THE
MOISTURE ADVECTION AND DPVA AHEAD OF THE UPPER LOW/SHORTWAVE...SOME
SCATTERED SHOWER AND THUNDERSTORM ACTIVITY SHOULD BE PRESENT AND
PERSIST THROUGH THE NIGHT. 16.00Z NAM/GFS/CANADIAN ALL INDICATE
PRECIPITATION...BUT IT IS JUST A MATTER HOW FAR SOUTH IT GETS WHICH
GOES BACK TO THE MODEL TIMING DIFFERENCES MENTIONED EARLIER. HAVE
FOLLOWED THE MAJORITY SOLUTION OF A SLOWER APPROACH...WHICH RESULTS
IN THE HIGHEST CHANCES OF 30-40 OVER THE NORTHERN 1/3 OF THE
FORECAST AREA. DID EXTEND A 20 PERCENT CHANCE DOWN INTO SOUTHEAST MN
IN THE EVENT THE FASTER 16.00Z GFS COMES TRUE. MOST OF THESE CHANCES
ARE ALSO AFTER MIDNIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 307 AM CDT SUN JUN 16 2013
MONDAY INTO MONDAY NIGHT...SHORTWAVE LURKING UP TO OUR NORTHWEST AT
12Z MONDAY IS WELL AGREED UPON TO REACH THE I-90 CORRIDOR IN THE
FORECAST AREA AT 00Z TUESDAY...DESPITE THE MODEL DIFFERENCES ON
TIMING BEFORE THAT. ACCOMPANYING THE SHORTWAVE WILL BE A COLD FRONT
WHICH SHOULD GRADUALLY MAKE ITS WAY SOUTH THROUGH THE AREA DURING
THE DAY. ANTICIPATING SCATTERED SHOWER/THUNDERSTORM ACTIVITY THAT
WAS DROPPING INTO NORTHERN PORTIONS OF THE AREA LATE SUNDAY NIGHT TO
CONTINUE DROPPING SOUTH AND POSSIBLY WEAKEN AS THE 850MB MOISTURE
TRANSPORT FALLS APART. AS INSTABILITY BUILDS DURING THE DAY...
THUNDERSTORMS MAY FORM BOTH ALONG THE COLD FRONT IN THE SOUTHERN
PORTION OF THE FORECAST AREA...AS WELL AS UNDER THE COLDER CORE OF
AIR ASSOCIATED WITH THE SHORTWAVE. THUS...IT APPEARS MONDAY WILL BE
AN OFF AND ON PRECIP DAY AT THIS TIME. 0-6KM SHEAR IS NOT THE
GREATEST FOR THINKING SEVERE WEATHER...GENERALLY 30-35 KT OVER THE
SOUTHERN TWO THIRDS OF THE AREA IN THE AFTERNOON. THIS WOULD SUGGEST
MOST OF THE CONVECTION TAKING ON A MULTI-CELLULAR APPEARANCE.
HOWEVER...FREEZING LEVELS DO LOWER AT 21Z TO 9000 FT OVER THE NORTH
TO 10500-11000 FT AGL IN THE SOUTH...SO HAIL IS A DEFINITE
POSSIBILITY FROM THE AFTERNOON STORMS. ANY CONVECTION FROM MONDAY
AFTERNOON SHOULD DIMINISH QUICKLY DURING THE EVENING WITH LOSS OF
DAYTIME HEATING...THE SHORTWAVE HEADING INTO NORTHERN ILLINOIS AND
HIGH PRESSURE BUILDING IN FROM THE NORTH.
TUESDAY INTO TUESDAY NIGHT...WHAT LOOKED TO BE A QUIET PERIOD FOR
MANY DAYS IS BECOMING A LITTLE MORE PROBLEMATIC. THE 15.00Z ECMWF
SHOWED A FAIRLY POTENT SHORTWAVE DROPPING THROUGH WESTERN PORTIONS
OF THE FORECAST AREA DURING THE DAYTIME HOURS ON TUESDAY. SO
ALTHOUGH A RIDGE OF HIGH PRESSURE IS IN PLACE AT THE SURFACE...THE
COLDER AIR ALOFT ACCOMPANYING THE SHORTWAVE RESULTED IN
PRECIPITATION. TODAY...THE 16.00Z NAM/UKMET/GFS/ECMWF/CANADIAN
CONTINUE TO SHOW THIS SHORTWAVE BUT ITS TRACK IS ALL OVER THE PLACE.
THE NAM/UKMET/ECMWF DROP IT SOUTHEAST THROUGH CENTRAL WI WHILE THE
GFS AND 15.12Z ECMWF BRING IT THROUGH SOUTHEAST MN AND NORTHEAST
IA. THE CANADIAN LIES BETWEEN THE TWO. FOR REFERENCE...THE SHORTWAVE
RIGHT NOW SITS ALONG THE SOUTHERN ALBERTA/SASKATCHEWAN BORDER.
DESPITE THE TRACK DIFFERENCES...LIGHT MODEL QPF IS MOSTLY CENTERED
WEST OF THE MS RIVER DURING THE TUESDAY DAYTIME HOURS. THIS AREA
APPEARS TO BE THE BEST JUXTAPOSITION OF DIURNAL HEATING/LOW LEVEL
MOISTENING AND THE COOL AIR ALOFT WITH THE SHORTWAVE. DESPITE SEEING
THE LIGHT QPF SIGNAL...HAVE CONTINUED TO STAY WITH THE DRY FORECAST
THINKING THAT THE MODELS MAY BE OVERDOING LOW LEVEL DEWPOINTS. A
NORTHEAST SURFACE FLOW OUT OF HIGH PRESSURE IN UPPER MI SHOULD
PROVIDE A DRY FLOW OF AIR. AFTER THE SHORTWAVE PASSES...A DRY AND
COOL NIGHT IS IN STORE FOR TUESDAY NIGHT AS HIGH PRESSURE SETTLES
IN.
WEDNESDAY THROUGH SATURDAY NIGHT...
THE UPPER LOW CURRENTLY SITTING OFF THE PACIFIC NORTHWEST COAST IS
FORECAST TO SLOWLY PUSH EAST THE NEXT FEW DAYS...ENCOMPASSING MUCH
OF THE PACIFIC NORTHWEST ON WEDNESDAY. DOWNSTREAM RIDGING SHOULD BE
IN PLACE FROM THE NORTHWEST TERRITORIES DOWN INTO THE SOUTHERN
PLAINS...PLACING THE FORECAST AREA IN SUBSIDENCE. MODELS REMAIN IN
GOOD AGREEMENT KEEPING THE AREA DRY WEDNESDAY AND WEDNESDAY
NIGHT...STAYING IN SUBSIDENCE AND DRY AIR WITH HIGH PRESSURE NEARBY
AT THE SURFACE. THE PATTERN THEN BEGINS TO CHANGE ACCORDING TO THE
16.00Z ECMWF/CANADIAN/GFS AND GFS ENSEMBLES...SUGGESTING THE
TROUGHING THAT HAS BEEN PERSISTENT OVER SOUTHEAST CANADA BEGINS TO
LIFT OUT. ADDITIONALLY...THE UPPER LOW IN THE PACIFIC NORTHWEST
SLOWLY EJECTS EAST-NORTHEAST. ALL THESE CHANGES OCCURRING TO THE
UPPER LEVEL PATTERN SETS UP WARM ADVECTION AND A DECENT RETURN OF
GULF OF MEXICO MOISTURE BACK TOWARDS THE UPPER MISSISSIPPI RIVER
VALLEY REGION. AS A RESULT...PRECIPITATION CHANCES BEGIN TO SLOWLY
INCREASE...AS EARLY AS THURSDAY. MUCH OF THE FORECAST FROM THURSDAY
NIGHT THROUGH SATURDAY NIGHT IS BROAD BRUSHED WITH 30-40 PERCENT
CHANCES AS THE FORECAST PATTERN LENDS ITSELF TO MULTIPLE ROUNDS OF
CONVECTION. WILL LIKELY HAVE TO WAIT MANY DAYS TO NAIL DOWN ANY
TIMING OR LOCATION OF THIS CONVECTION. CERTAINLY POTENTIAL HERE FOR
HEAVY RAIN...AND POSSIBLY SEVERE WEATHER TOO...BUT THOSE DETAILS ARE
TOO EARLY TO HASH OUT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 625 AM CDT SUN JUN 16 2013
SUNRISE/DIURNAL WARMING AND A BIT OF AN INCREASE IN BOUNDARY LAYER
GRADIENT WINDS WILL QUICKLY DISSIPATE THE VALLEY FOG IN THE KLSE
AREA THIS MORNING. HIGH PRESSURE AND DRIER NORTHWEST FLOW WILL THEN
PREVAIL ACROSS THE AREA FOR TODAY/THIS EVENING...WITH GOOD VFR
CONDITIONS THRU MUCH OF THIS TAF PERIOD.
A WEAK COLD FRONT APPROACHES LATER TONIGHT...WITH AN INCREASE OF
MAINLY MID LEVEL MOISTURE/CLOUDS. THE FRONT MAY BRING SOME WDLY SCT
SHRA/ISOLATED TSRA INTO THE AREA LATE TONIGHT. GIVEN ISOLATED/WDLY
SCT COVERAGE AND LOWER CONFIDENCE FOR THESE...LEFT VCSH/VCTS OUT OF
THE 06-12Z TAF PERIOD FOR NOW.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR WIZ017-029-
032>034-041>044-053.
MN...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR MNZ088-096.
IA...NONE.
&&
$$
UPDATE.......AJ/RRS
SHORT TERM...AJ
LONG TERM... AJ
AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
508 AM MDT SUN JUN 16 2013
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 500 AM MDT SUN JUN 16 2013
A FEW WEAK SHOWERS DEVELOPED OVER THE HIGH COUNTRY EARLY THIS MORNING
AHEAD OF A SHORTWAVE TROUGH MOVING TO THE NORTHWEST ACROSS THE GREAT
BASIN. A LINE OF SHOWERS AND ISOLATED STORMS DEVELOPED IN THE NORTHERN
PANHANDLE AS WELL ALONG WHAT LOOKS TO BE A WARM FRONT THAT IS MOVING
NORTH ACROSS THIS AREA. SHOULD SEE THIS ACTIVITY CONTINUE FOR THE
MOST PART THIS MORNING.
THE UPPER RIDGE AXIS WILL REMAIN OVER THE ROCKIES AS A SECOND UPPER
LEVEL WAVE WILL BEGIN TO DROP SOUTH INTO THE NORTHERN PLAINS THIS
AFTERNOON. AN ASSOCIATED WEAK COOL FRONT SLOWLY MOVING SOUTH ACROSS
THE FORECAST AREA EARLY THIS EVENING. FIRST THOUGH...A DEVELOPING
LEE SIDE TROUGH WILL MOVE SOUTHEAST ACROSS THE EASTERN PLAINS LATE
THIS MORNING AND AFTERNOON WITH SFC WINDS SHIFTING TO THE NORTH AND
THEN NORTHEAST THROUGH THIS TIME. TEMPERATURES WILL BE WARMER TODAY
THAN YESTERDAY AS A THERMAL RIDGE MOVES OVER THE FORECAST AREA AHEAD
OF THE COOL FRONT. WITH CONTINUED ENERGETIC AND MOIST SOUTHWEST FLOW
OVERHEAD IN ADDITION TO A NUMBER OF SFC FORCING MECHANISMS IN
PLACE...WILL SEE ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS ACROSS
THE FORECAST AREA TODAY. LOOKS TO BE A BROADER COVERAGE OF ACTIVITY
FOR TODAY THAN YESTERDAY WITH THE FOCUS FOR INITIATION ALONG THE
DEVELOPING LEE TROUGH IN ADDITION TO THE HIGHER TERRAIN FEATURES
THAT ARE THE MOUNTAINS AND CHEYENNE RIDGE. UPWARDS OF 2000 J/KG OF
CAPE WITH MINIMAL CAP ALONG AND EAST OF THE LARAMIE RANGE COMBINED
WITH 40 TO 50 KT OF DEEP LAYER SHEAR WILL INCREASE CHANCES ONCE
AGAIN FOR SOME OF THE STORMS TO ORGANIZE AND BECOME SEVERE. WITH
WEAK LOW LEVEL SHEAR AND HIGH LCLS IN PLACE DUE TO WARMER TEMPS OVER
THE MAJORITY OF THE REGION...THE MAIN THREATS WILL ONCE AGAIN BE
LARGE HAIL AND DAMAGING DOWNBURST WINDS. INCREASING LOW LEVEL
SHEAR AND LOWER LCLS LATE THIS AFTERNOON AHEAD OF THE LEE TROUGH
IN THE SOUTHERN NEBRASKA PANHANDLE WILL BRING A LOW POSSIBILITY
FOR AN ISOLATED TORNADO AS WELL. ALTHOUGH THE MAIN LIKELIHOOD OF
SEVERE POTENTIAL WILL BE EAST OF THE LARAMIE RANGE...CANNOT RULE
OUT A COUPLE STORMS APPROACHING SEVERE LIMITS OUT WEST ESPECIALLY
FOR DOWNBURST WINDS AS FORECAST SOUNDINGS IN THIS AREA SHOW A
PRONOUNCED INVERTED-V PROFILE BY LATE AFTERNOON. COULD SEE OVERALL
ACTIVITY LAST LONGER INTO THE NIGHT DEPENDING ON THE MOVEMENT OF
THE COOL FRONT AS IT PUSHES SOUTH ACROSS THE FORECAST AREA IN THE
LATE EVENING.
THE UPPER LEVEL RIDGE AXIS WILL REMAIN OVER THE ROCKIES AND WILL
AMPLIFY SLIGHTLY ON MONDAY AS THE NORTHERN SHORTWAVE FEATURE DIGS
INTO THE NORTHERN PLAINS. TEMPERATURES AT THE SURFACE AND ALOFT WILL
BE SLIGHTLY COOLER OVERALL BEHIND THE COOL FRONT...WHICH LOOKS TO
REMAIN STALLED ALONG THE LARAMIE RANGE THROUGH THE DAY.
EAST-SOUTHEASTERLY UPSLOPE WINDS BEHIND THE FRONT WILL INCREASE
MOISTURE ADVECTION AND WILL PROVIDE STRONG CONVERGENCE ALONG THE
LARAMIE RANGE. SO THE THREAT FOR SHOWERS AND THUNDERSTORMS WILL
CONTINUE FOR THE FORECAST AREA THROUGH MONDAY. SLIGHTLY COOLER TEMPS
ALOFT WILL REDUCE THE CAP IN THE AFTERNOON...SO ONCE AGAIN EXPECTING
SOME STORMS TO BECOME SEVERE ALONG AND EAST OF THE LARAMIE RANGE IN
THE AFTERNOON.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 500 AM MDT SUN JUN 16 2013
THE UPPER LEVEL PATTERN WILL BE DOMINATED BY RIDGING FROM THE
ROCKIES TO THE EASTERN GREAT PLAINS...WITH TROUGHS ANCHORED OVER
THE WESTERN AND EASTERN CONUS. THE MODELS CONTINUE TO BRING WEAK
UPPER LEVEL DISTURBANCES FROM THE GREAT BASIN UP AND OVER THE RIDGE
INTO THE GREAT PLAINS THROUGH THE EARLY PART OF THE WEEK. A SURFACE
DRY LINE OR TROUGH WILL BE QUASI-STATIONARY ACROSS THE EASTERN
WYOMING AND COLORADO PLAINS DURING THE SAME TIME PERIOD. MOIST
UNSTABLE AIR ALONG AND EAST OF THIS FEATURE WILL INTERACT WITH THE
DISTURBANCES TO PRODUCE MAINLY AFTERNOON AND EVENING CONVECTION.
TSTORM COVERAGE WILL GENERALLY BE SCATTERED EAST OF THE LARAMIE
RANGE...WITH MORE ISOLATED COVERAGE TO THE WEST. SOUTHERLY WINDS
WILL BE BREEZY TUESDAY...WITH MORE WIDESPREAD BREEZY CONDITIONS
ACROSS THE WESTERN PANHANDLE AND WEST OF THE LARAMIE RANGE FOR
WEDNESDAY. WEDNESDAY WILL BE DRY WITH THE UPPER RIDGE AND SUBSIDENT
FLOW OVER THE CWFA. A FRONT WILL PUSH SOUTH ACROSS THE HIGH PLAINS
LATE THURSDAY WITH WINDS SHIFTING FROM SOUTHERLY TO EASTERLY. A
LOW LEVEL MOISTURE AXIS WILL EXTEND FROM EAST CENTRAL WYOMING TO
THE WESTERN PANHANDLE FRIDAY AND SATURDAY. ISOLATED DIURNAL
CONVECTION WILL ONCE AGAIN DEVELOP ALONG AND EAST OF THIS BOUNDARY.
TEMPERATURES THROUGHOUT THE LONG TERM PERIOD WILL AVERAGE SEASONAL
NORMALS. WARMEST PERIOD WILL BE THE END OF THE WEEK WITH DRIER
SOUTHWEST FLOW IN PLACE AND 700MB TEMPERATURES FROM 14 TO 18C.
TEMPERATURES WILL COOL SLIGHTLY FOR THE WEEKEND AS HIGH PRESSURE
RIDGE BUILDS SOUTH THROUGH MONTANA AND WYOMING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY EVENING)
ISSUED AT 1041 PM MDT SAT JUN 15 2013
EXPECTING FAIRLY CALM CONDITIONS OVERNIGHT. THE LATEST HRRR MODEL
IS SHOWING SOME IFR CEILINGS AT KSNY AND KCYS AROUND THE 09-10Z
TIME FRAME. GIVEN THE HIGH FALSE ALARM RATE WITH THE HRRR THE PAST
COUPLE WEEKS THOUGH...DECIDED TO GO AGAINST THIS GUIDANCE AND ONLY
HAVE SCT008 IN THE TAFS. ANOTHER ROUND OF CONVECTION SUNDAY
AFTERNOON WITH BEST CHANCES FOR TSTMS AT KCYS...KBFF AND KSNY.
&&
.FIRE WEATHER...
ISSUED AT 500 AM MDT SUN JUN 16 2013
A NUMBER OF WEATHER DISTURBANCES MOVING OVER THE DISTRICT THROUGH
EARLY THIS WEEK WILL MAINTAIN CHANCES FOR SHOWERS AND THUNDERSTORMS
THROUGH THIS TIME. ENOUGH MOISTURE LOOKS TO BE AVAILABLE FOR WETTING
RAINS OUT OF MOST STORMS...ALTHOUGH BREEZY SOUTHWEST WINDS AND
HUMIDITIES IN THE LOW TEENS ARE EXPECTED AGAIN TODAY FOR THE HIGH
COUNTRY WHICH COULD ATTRIBUTE TO LITTLE RAINFALL IN THIS AREA.
HUMIDITIES WILL REMAIN ON THE LOW SIDE OUT WEST FOR THE NEXT COUPLE
OF DAYS IN ADDITION TO BREEZY SOUTH TO SOUTHWEST WINDS.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...RJM
LONG TERM...JAMSKI
AVIATION...CLAYCOMB
FIRE WEATHER...RJM
AREA FORECAST DISCUSSION
NWS ALBANY NY
141 PM EDT SUN JUN 16 2013
.SYNOPSIS...
A LOW PRESSURE SYSTEM AND ITS ASSOCIATED UPPER LEVEL
DISTURBANCE WILL BRING A CHANCE OF SHOWERS AND A FEW THUNDERSTORMS
TO EASTERN NEW YORK AND WESTERN NEW ENGLAND TODAY. SOME SCATTERED
SHOWERS AND THUNDERSTORMS ARE POSSIBLE AHEAD OF A COLD FRONT ON
MONDAY. THE BOUNDARY MAY STALL SOUTH OF THE CAPITAL REGION FOR MORE
SHOWERS TO LINGER INTO TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 130 PM EDT... LITTLE CHANGES TO THE ONGOING FORECAST AS CLOUDS
CONTINUE TO THICKEN THEREFORE REDUCING SOLAR INSOLATION. WE HAVE
LOWERED TEMPS A COUPLE OF DEGREES FOR THE AFTERNOON. RAIN SHIELD
WAS IMPACTING MAINLY TH DACKS WITH EXPERIENTIAL REFLECTIVITIES FROM
THE HRRR SUGGEST THE MAIN RAIN SHIELD WILL BE NORTH OF THE CAPITAL
REGION WITH A DEVELOPING TRAIL OF CONVECTION DEVELOPING SOUTH OF I90
LATER THIS AFTERNOON. CHANCES FOR THUNDER CONTINUE TO DIMINISH AS
SLIGHT CHANCE WORDING LOOKS FINE FOR NOW.
AS OF 930 AM EDT...HIGH PRESSURE CONTINUES TO MOVE EAST OF THE
CAROLINAS THIS MORNING...AS LOW PRESSURE IS APPROACHING FROM
GEORGIAN BAY. A WEAK PRE FRONTAL THERMAL SFC TROUGH AHEAD OF THE
SFC WAVE WILL INCREASE THE THREAT OF SHOWERS WITH ISOLD
THUNDERSTORMS FROM LATE THIS MORNING INTO THE AFTERNOON. CLOUDS
WILL THICKEN AND LOWER FROM WEST TO EAST THROUGH THIS MORNING.
SOME LIGHT SHOWERS HAVE DEVELOPED ACROSS WRN NY AND NRN PA...AS
THE LOW TO MID LEVEL WARM ADVECTION INCREASES.
THE BETTER JET DYNAMICS STAY NORTH OF THE FCST AREA. A MID LEVEL
SHORT-WAVE IN THE NEAR ZONAL FLOW WILL HELP ENHANCE THE SHOWERS
COUPLED WITH THE THERMAL ADVECTION. THE BEST MOISTURE CONVERGENCE
TIED TO THE BETTER QG LIFT IS OVER THE NRN HALF OF THE FCST AREA.
THE SHOWALTER VALUES GRAZE 0 C...AND THE SBCAPE OR MUCAPES REMAIN
ON THE LOW SIDE. THE PAUCITY OF INSTABILITY /GENERALLY IN THE
200-500 J/KG RANGE/ SHOULD CURTAIL ANY WIDESPREAD THUNDERSTORM
ACTIVITY. SOME RUMBLES MAY BE POSSIBLE...AND WE HAVE PHRASED IT AS
A SLIGHT CHC OF THUNDERSTORMS IN THE AFTERNOON.
THE POPS WERE KEPT IN THE LIKELY RANGE FROM THE CAPITAL
REGION...NRN CATSKILLS NORTHWARD. CHC POPS WERE USED SOUTH AND
EAST OF THE CAPITAL DISTRICT. TEMPS WILL DEPEND ON THE AMOUNT OF
HEATING THAT OCCURS AHEAD OF THE SFC CYCLONE AND ITS PREFRONTAL
SFC TROUGH. HIGHS IN THE U60S TO M70S ARE FORECASTED FROM THE
EASTERN CATSKILLS...CAPITAL REGION...NRN BERKSHIRES
NORTHWARD...WITH U70S TO L80S SOUTH...WHERE A BIT MORE SUNSHINE IS
EXPECTED. PWATS WILL BRIEFLY BE IN THE 1-1.50 INCH RANGE WITH THE
SHOWERS/ISOLD TSTMS. THE HIGHEST QPF OF A QUARTER TO A HALF AN
INCH IS FROM ROUGHLY FROM THE CAPITAL REGION NORTH AND WEST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
TONIGHT...THE SHOWERS AND ISOLD THUNDERSTORMS SHOULD DIMINISH
EARLY IN THE EVENING. PARTIAL CLEARING IS EXPECTED...AND THE SFC
TO BOUNDARY LAYER WINDS WILL VEER TO THE SOUTHWEST TO WEST. IN
LOCATIONS...THE WINDS WILL GO LIGHT TO CALM. PATCHY FOG WAS ADDED
TO THE FCST FOR LOCATIONS AT 1000 FT AGL OR LOWER. A COLD FRONT
WILL REMAIN WELL NORTH AND WEST OF THE REGION OVER THE GREAT LAKES
REGION...AND MIDWEST. LOWS WERE USED CLOSE TO A BLEND OF THE MAV-
MET MOS VALUES WITH 50S TO L60S OVER THE REGION.
MONDAY-MONDAY NIGHT...ANOTHER WEAK SFC LOW WILL PIVOT AROUND THE
UPPER LEVEL TROUGH CENTERED OVER JAMES BAY. THIS SFC WAVE WILL
PASS NORTH OF THE REGION OVER S-CNTRL QUEBEC. THE COLD FRONT
STARTS TO DESCEND SOUTH AND EAST OF THE GREAT LAKES REGION...AND
ST LAWRENCE RIVER VALLEY. THE TIMING OF THIS BOUNDARY IS TRICKY
BASED ON THE CANADIAN GUIDANCE/GFS/ECMWF/NAM. SOME DECENT HEATING
IS LIKELY AHEAD OF THE FRONT...ESPECIALLY FROM KALB SOUTH. THE MID
LEVEL LAPSE RATES ARE NOT SUPER IMPRESSIVE...IN THE 6-6.5 C/KM.
THE SBCAPES ARE MUCH LOWERS ON THE GFS COMPARED TO NAM...SINCE THE
NAM HAS HIGHER DEWPTS /LOWER TO M60S/ OVER THE SRN TIER. THE GFS
INDICATES SBCAPES OF 400-800 J/KG WITH THE NAM HAVING AN AXIS OF
1000-1500 J/KG SOUTH OF THE CAPITAL REGION. THE 0-6 KM BULK SHEAR
DOES INCREASE TO 40-45 KTS FOR POSSIBILITY OF DEEP ORGANIZED
CONVECTION. THE FLOW BEING UNIDIRECTIONAL IN THE LOW TO MID LEVELS
WOULD INDICATE SOME LINEAR DEVELOPMENT IS POSSIBLE...BUT A CAVEAT
TO ALL THE CONVECTION POSSIBILITIES IS THE SFC TO BOUNDARY LAYER
FLOW SHIFTING TO SOUTHWEST CAUSING DOWNSLOPING OFF THE HELDERBERGS
AND CATSKILLS...ALLOWING THE SFC DEWPTS TO DROP OFF.
SCT THUNDERSTORMS...SOME POTENTIALLY STRONG COULD BE POSSIBLE
ACROSS THE REGION. ANY SEVERE THREAT LOOKS ISOLD AT BEST SINCE THE
DEGREE OF INSTABILITY IS STILL IN QUESTION ALONG WITH THE TIMING
OF THE FRONT. THE NAM IS INDICATING PORTIONS OF THE FCST AREA WILL
BE IN THE FAVORABLE RIGHT REAR QUAD OF AN H250 JET STREAK TO HELP
ENHANCE ANY CONVECTION. LEANED CLOSER TO WARMER GFSMOS VALUES WITH
THE 10-METER WINDS SHOWING THE SW FLOW NICELY. EXPECT MAX TEMPS IN
THE U70S TO M80S IN THE VALLEYS...WITH GENERALLY 70S OVER THE
HIGHEST TERRAIN. THE SHOWERS AND THUNDERSTORMS SHOULD DECREASE A
BIT IN COVERAGE OVERNIGHT WITH THE FRONT POTENTIALLY STALLING OVER
E-CNTRL NY AND NEW ENGLAND. LOWS WILL GENERALLY BE IN THE M50S
ACROSS THE NRN ZONES TO U50S TO L60S OVER THE SOUTHEAST.
TUE-TUE NIGHT...THE NWP GUIDANCE IS IN DISAGREEMENT ON THE
LOCATION OF THE FRONT...AND THE MOVEMENT OF A WAVE OR MCS ALONG
IT. THE GFS BLASTS THE FRONT THROUGH...AND THE UPPER TROUGH
AMPLIFIES TO THE NORTH ALLOWING A NICE DAY. THE ECMWF/NAM/CAN GGEM
STALL THE BOUNDARY SOUTH OF THE CAPITAL REGION FOR SOME OVER
RUNNING SHOWERS AND ISOLD THUNDERSTORMS. A LONG CONFIDENCE FCST
HERE...AND WE HAVE KEPT A CHC OF SHOWERS AND A SLIGHT CHC OF
THUNDERSTORMS IN BASED ON THE STRONGER CONSENSUS IN THE GUIDANCE.
TRENDED TOWARDS DRIER WX TUE NIGHT WITH NW FLOW ALOFT AND SFC HIGH
BUILDING IN FROM GREAT LAKES REGION. HIGHS WILL BE IN 70S ACROSS
MOST OF THE REGION ON TUE WITH U60S OVER THE SRN GREENS AND SRN
DACKS. LOWS IN THE COLD ADVECTION REGIME TUE NIGHT WILL BE IN THE
40S TO L50S.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
MODEL GUIDANCE CONTINUES TO BE IN GENERAL AGREEMENT ABOUT THE
LONGWAVE PATTERN WITH A TROUGH OVER THE GREAT LAKES REGION AND
NORTHEAST...A CLOSED LOW OVER THE PACIFIC NORTHWEST AND A RIDGE
OVER THE CENTRAL CONUS.
DESPITE BEING UNDER THE TROUGH...HEIGHTS ARE EXPECTED TO RISE WITH
HIGH PRESSURE ORIGINATING FROM CANADA BUILDING IN AT THE SURFACE
BRINGING SOME MUCH NEEDED FAIR WEATHER TO THE REGION FOR A
COUPLE/FEW DAYS.
BY THE START OF THE WEEKEND...FLOW ALOFT ACROSS THE REGION SHOULD BE
ZONAL. MODEL GUIDANCE IS NOT IN AGREEMENT MOVING INDIVIDUAL PIECES
OF ENERGY THROUGH THIS FLOW. HAVE GONE WITH CLIMATOLOGICAL POPS
(20-30 PERCENT) FOR SATURDAY.
TEMPERATURES WILL START THE PERIOD OUT BELOW NORMAL MID WEEK HOWEVER
THEY WILL MODERATE A COUPLE DEGREES EACH DAY WITH NORMAL READINGS
EXPECTED BY THE END OF THE WEEK.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
A LOW PRESSURE SYSTEM IS APPROACHING OUR REGION FROM THE GREAT
LAKES REGION. HIGH AND MID LEVEL CLOUDS HAVE ALREADY THICKENED
ACROSS THE REGION. THE CLOUDS WILL THICKEN AND LOWER AS THE DAY
PROGRESSES AND THE APPROACHING LOW GETS CLOSER. SHOWERS WILL
ACCOMPANY THE LOW AS IT MOVES ACROSS THE REGION THIS AFTERNOON AND
EVENING WITH THE BEST CHANCE AT KGFL. THERE IS A CHANCE OF
THUNDERSTORMS TODAY HOWEVER THE THREAT IS LOW ENOUGH THAT IT IS
NOT MENTIONED IN TAFS...JUST HAVE SHOWERS. MVFR CONDITIONS ARE
EXPECTED TO DEVELOP IN THE WAKE OF LOW OVERNIGHT RETURNING TO VFR
MONDAY MORNING.
WINDS WILL BE SOUTH TO SOUTHWEST THIS AFTERNOON AT 5-8 KTS WITH
GUSTS OVER 15 KTS AT KGFL WHERE SHOWERS WILL BE MORE NUMEROUS.
WINDS WILL SHIFT TO THE WEST WITH THE PASSAGE OF THE LOW AND
DIMINISH TONIGHT AND THEN SOUTHWEST TO WEST AT 5-8 KTS MONDAY
MORNING.
OUTLOOK...
MON...MAINLY VFR. CHC -SHRA/-TSRA. MAINLY IN THE AFTN/EVNG.
TUE...MAINLY VFR. CHC -SHRA. SLIGHT CHC -TSRA.
TUE NIGHT-FRI...VFR. NO SIG WX.
&&
.FIRE WEATHER...
NO FIRE WEATHER RELATED PROBLEMS ARE EXPECTED THE NEXT SEVERAL
DAYS DUE TO THE PERSISTENT WET PATTERN SINCE LATE MAY.
A LOW PRESSURE SYSTEM AND ITS ASSOCIATED UPPER LEVEL
DISTURBANCE WILL BRING A CHANCE OF SHOWERS AND A FEW THUNDERSTORMS
TO EASTERN NEW YORK AND WESTERN NEW ENGLAND TODAY. SOME SCATTERED
SHOWERS AND THUNDERSTORMS ARE POSSIBLE AHEAD OF A COLD FRONT ON
MONDAY. THE BOUNDARY MAY STALL SOUTH OF THE CAPITAL REGION FOR MORE
SHOWERS TO LINGER INTO TUESDAY.
A GOOD RECOVERY IS EXPECTED IN THE RH TRENDS EACH MORNING. THE SCT
SHOWERS AND ISOLATED TO SCATTERED THUNDERSTORM TODAY INTO EARLY
NEXT WEEK WILL KEEP THE PERSISTENT WET CONDITIONS ONGOING ACROSS
EASTERN NEW YORK AND WESTERN NEW ENGLAND.
&&
.HYDROLOGY...
FLOWS REMAIN ABOVE NORMAL FOR MID JUNE ACROSS THE HYDRO SERVICE
AREA. MINOR FLOODING CONTINUES ACROSS PORTIONS OF THE HOUSATONIC
BASIN IN NW CT FROM THE HEAVY RAINFALL A FEW DAYS AGO.
RAINFALL TODAY INTO TONIGHT WILL RANGE FROM A QUARTER TO HALF AN
INCH FROM THE CAPITAL REGION AND THE NORTHERN CATSKILLS NORTHWARD
WITH ONE TO TWO TENTHS OF AN INCH TO THE SOUTH.
QPF WILL BE HIGHLY VARIABLE WITH THE COLD FRONTAL PASSAGE MONDAY
INTO TUESDAY WITH A FEW HUNDREDTHS TO A FEW TENTHS OF AN INCH
POSSIBLE WITH LOCALLY HIGHER AMOUNTS WITH ANY THUNDERSTORMS.
DRY WEATHER IS EXPECTED TO RETURN TUESDAY NIGHT INTO THE MID WEEK
ALLOWING RIVERS TO CONTINUE TO GRADUALLY LOWER FROM THE VERY WET
WEATHER THE PAST FEW WEEKS.
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...WASULA
NEAR TERM...BGM/11/WASULA
SHORT TERM...WASULA
LONG TERM...IAA
AVIATION...IAA/11
FIRE WEATHER...WASULA
HYDROLOGY...11/WASULA
WWW.WEATHER.GOV/ALBANY
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
345 PM EDT SUN JUN 16 2013
.DISCUSSION...
TONIGHT...LATEST RUC ANALYSIS SHOWS AN AIRMASS LARGELY LACKING IN
ANY SIGNIFICANT MID/UPR LVL LIFTING MECHANISMS TO SUPPORT DIURNAL
CONVECTION MUCH PAST SUNSET. H50 TEMPS AOA -6C...NO SIG H85-H50
VORTICITY COUPLETS...NEGATIVE MID LVL OMEGA CONFINED TO THE W FL
COAST...AND CONVERGENT UPR LVLS OUTSIDE THE IMMEDIATE VCNTY OF
EXISTING CONVECTION. AS IF TO EMPHASIZE...CG LTG ACTIVITY HAS BEEN
ALMOST ABSENT...NLDN RECORDING FEWER THAN A DOZEN STRIKES OVER E
CENT FL AS OF 19Z.
DESPITE HIGH MOISTURE LVLS...LCL AIRMASS IS SIMPLY TOO TORPID TO
SUPPORT CONVECTION ONCE DAYTIME HEATING IS LOST. WILL GO WITH A
PRE-FIRST PD TO COVER CURRENT CONVECTION...SLGT CHC OF TSRAS OVER
THE NRN CWA THRU 02Z THOUGH EVEN THIS MAY BE GENEROUS. SFC DEWPOINTS
IN THE L/M70S WILL COMBINE WITH LIGHT SERLY FLOW TO KEEP MIN TEMPS
ARND 5F ABV AVG.
MON-TUE...H100-H70 ATLC RIDGE WILL RELOCATE OVER THE S HALF OF THE
PENINSULA AS A STORM SYSTEM IN THE NRN STREAM ROLLS OVER THE NRN
PERIPHERY OF THE RIDGE. ONCE THERE...IT WILL MERGE WITH THE MID LVL
RIDGE OVER THE GOMEX...WITH THE DLM RIDGE AXIS LOCATED BTWN MIAMI
AND TAMPA. THIS WILL GENERATE A DEFINITIVE SWRLY STEERING FLOW ACRS
CENTRAL FL.
THIS FLOW REGIME TENDS TO FOCUS DIURNAL CONVECTION ALONG THE COAST E
FL COAST AS THE WEST COAST SEA BREEZE PENETRATES FURTHER INLAND
WHILE THE EAST COAST BREEZE IS FORCED TO OVERCOME THE INERTIA OF THE
WRLY FLOW. MERGER EXPECTED TO OCCUR ALONG AND E OF THE FL TURNPIKE
WITH THE WRLY FLOW PUSHING STORMS BACK TO THE E COAST.
THE SWRLY FLOW WILL KEEP TEMPS A FEW DEG ABV AVG...MAX TEMPS TO WARM
INTO THE L/M90S OVER MOST OF THE CWA...EXCEPTIONS WOULD BE U80S
ALONG THE IMMEDIATE COAST SHOULD THE EAST COAST SEA BREEZE FORM A
LITTLE EARLIER THAN ANTICIPATED. MIN TEMPS L/M70S AREAWIDE.
EXTENDED...(MODIFIED PREV DISC)
LITTLE CHANGE IN THE FORECAST FOR THE EXTENDED PERIOD AS EAST-WEST
ORIENTED 500MB RIDGE OVER FLORIDA CONTINUES TO WEAKENS AND SHIFT
SOUTH AS A TROUGH MOVES INTO THE EASTERN US WEDNESDAY AND LINGERS
THROUGH THE END OF THE WEEK. THE ACCOMPANYING SURFACE FRONTAL
BOUNDARY WILL MAKE IT AS FAR SOUTH AS NORTH FLORIDA ON THU...THOUGH
THE GFS IS A LITTLE MORE BULLISH IN BRINGING A MORE COHERENT
BOUNDARY INTO THE CENTRAL PORTION OF THE STATE.
ALL IN ALL HOWEVER...IT WILL BE A FAIRLY TYPICAL SUMMERTIME PATTERN
WITH SCATTERED SHOWERS AND THUNDERSTORMS EACH AFTERNOON ALONG BOTH
SEA BREEZES WITH POPS 30-40 PERCENT. THE EXACT LOCATION OF THE SEA
BREEZE COLLISION AND BEST RAIN CHANCES WILL DEPEND UPON WHERE THE
RIDGE AXIS SETS UP...BOTH MODELS POINT TO IT BEING SOUTH OF THE AREA
ON TUESDAY AND WEDNESDAY (FAVORING THE EASTERN SIDE OF THE PENINSULA
FOR RAIN) WITH A MORE DIFFUSE PATTERN THURS/FRI DUE TO THE PRESENCE
OF THE FRONTAL BOUNDARY.
RAIN CHANCES LOOK TO INCREASE AS WE HEAD INTO NEXT WEEKEND AS BOTH
THE GFS AND ECMWF SHOW A WEAK TROPICAL WAVE MOVING THROUGH THE
NORTHERN CARIBBEAN AND SOUTH FLORIDA ON SATURDAY.
MIDWEEK WILL SEE THE WARMEST DAYS WITH SLOWER EAST COAST SEA BREEZE
DEVELOPMENT. OVERALL HIGH TEMPS IN THE LOW TO MID 90S OVER THE
INTERIOR AND UPPER 80S/AROUND 90 AT THE COAST. OVERNIGHT LOWS ALONG
THE COAST IN THE MID 70S WITH LOW TO MID 70S OVER THE INTERIOR.
&&
.AVIATION...
THRU 16/24Z...SCT MVFR SHRAS/IFR TSRAS W OF KTIX-KOBE...ISOLD
SHRA/TSRAS E OF KTIX-KOBE...FC PSBL OVER ATLC S OF KFPR. BTWN
17/00Z-17/02Z...SLGT CHC IFR TSRAS N OF KISM-KTIX. BTWN
17/02Z-17/08Z...VFR ALL SITES. BTWN 17/08Z-17/14Z...LCL MVFR/IFR
CIGS IN STRATUS N OF KISM-KTIX.
&&
.MARINE...
TONIGHT...HIGH PRES RIDGE BUILDING OVERHEAD WILL GENERATE A GENTLE
TO MODERATE S/SE BREEZE...SEAS GENERALLY IN THE 2-3FT NEARSHORE...
3-4FT OFFSHORE. ISOLD TSRAS MOVING OFFSHORE N OF CAPE CANAVERAL THRU
LATE EVNG...ISOLD TSRAS OVER THE GULF STREAM OVERNIGHT.
MON-TUE...ATLC RIDGE AXIS PARKED IN THE VCNTY OF LAKE OKEECHOBEE AND
THE NRN BAHAMAS WILL GENERATE A GENTLE TO MODERATE SRLY BREEZE WITH
2-4FT SEAS SOUTH OF SEBASTIAN INLET...MODERATE TO FRESH S/SWRLY
BREEZE N OF THE INLET WITH 3-5FT SEAS. OFFSHORE COMPONENT N OF THE
INLET WILL GENERATE CHOPPY SHORT PD WIND WAVES.
WED-THU...TROFFING PATTERN OVER THE ERN SEABOARD WILL KEEP THE ATLC
RIDGE AXIS SUPPRESSED OVER THE S HALF OF THE FL PENINSULA THRU
MIDWEEK...RESULTING IN A GENTLE TO MODERATE S-SW BREEZE. SEAS 2-4FT
S OF SEBASTIAN INLET...3-5FT N OF THE INLET. SCT SHRA/TSTM COVERAGE
THRU MID WEEK WITH STORMS MOVING OFFSHORE N OF SEBASTIAN INLET.
FRI...ERN SEABOARD TROF WILL WEAKEN LATE IN THE WEEK...ALLOWING THE
RIDGE TO DRIFT BACK TO THE N. WINDS WILL BACK TO THE S/SE AND
DIMINISH TO AOB 12KTS. SEAS SUBSIDING TO 2-3FT LATE THU NIGHT INTO
FRI. STORM COVERAGE TO DIMINISH AS STEERING FLOW ALOFT WEAKENS WITH
THE PASSING RIDGE AXIS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 75 89 73 89 / 20 50 20 40
MCO 74 93 73 92 / 20 50 20 30
MLB 76 89 74 88 / 20 50 20 40
VRB 76 88 75 88 / 10 50 20 30
LEE 74 92 73 92 / 20 40 20 30
SFB 75 93 74 93 / 20 50 20 40
ORL 75 93 74 93 / 20 50 20 30
FPR 76 89 74 88 / 10 40 20 30
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
FORECAST....BRAGAW
IMPACT WX...LASCODY
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
352 PM EDT SUN JUN 16 2013
.SYNOPSIS...
HIGH PRESSURE OVER THE AREA WILL WEAKEN TONIGHT. A WEAK SYSTEM
WILL APPROACH FROM THE WEST MONDAY BRINGING A SLOW MOVING COLD
FRONT AND INCREASING THE MOISTURE ACROSS THE REGION MONDAY
THROUGH TUESDAY. AN INCREASE IN THE CHANCES OF SHOWERS AND
THUNDERSTORMS IS ALSO EXPECTED MONDAY THROUGH TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
MODELS ARE IN GOOD AGREEMENT AS A SHORT WAVE APPROACHES FROM
THE WEST TONIGHT. THIS WILL SUPPRESS AND WEAKEN THE UPPER RIDGE
THAT HAS COVERED THE REGION THE LAST COUPLE OF DAYS. CLOUDS
WILL ALSO INCREASE AND KEEP TEMPERATURES FROM FALLING AS MUCH
AS THE PREVIOUS NIGHT. EXPECT LOWS TO BE IN THE UPPER 60S TO
AROUND 70. RAIN CHANCES WILL ALSO RISE TO ABOUT 10 PERCENT BUT
MAY INCREASE TO NEAR 20 PERCENT IN THE FAR WEST INCLUDING THE
NORTHERN PORTION OF THE CSRA NEAR THE 08Z-10Z TIME FRAME MONDAY
MORNING NEAR DAYBREAK. THERE WILL BE A SLIGHT CHANCE OF SHOWERS
THOSE LOCATIONS ALSO NEAR DAYBREAK MONDAY.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
A MID-UPPER LEVEL TROUGH WILL MOVE INTO THE REGION MONDAY
THROUGH TUESDAY WITH A COUPLE WEAK SHORT WAVES TRAVERSING
THE AREA MONDAY AND AGAIN ON TUESDAY. IN ADDITION...INCREASING
LOW LEVEL SOUTHWEST WIND FLOW WILL ADVECT MOISTURE INTO THE
FORECAST AREA. ALONG WITH THE INCREASE IN MOISTURE...THERE
WILL BE OVERNIGHT LOW CLOUDS IN THE FORM OF STRATUS BOTH
MONDAY MORNING AND TUESDAY MORNING. DAYTIME HEATING WILL
HELP BREAK UP THE LOW CLOUD DECK BUT THERE SHOULD BE PLENTY
OF MOISTURE FOR SHOWERS AND THUNDERSTORMS TO DEVELOP BOTH
MONDAY AND TUESDAY. PLAN ON CONTINUING THE 40-50 PERCENT
CHANCE OF SHOWERS AND THUNDERSTORMS MONDAY THROUGH TUESDAY.
CLOUDS ARE EXPECTED TO HOLD HIGHS BELOW 90 IN THE UPPER 80S
MONDAY AND MORE CLOUDS ON TUESDAY SHOULD HOLD HIGHS INTO THE
MIDDLE 80S. OVERNIGHT LOWS MONDAY NIGHT SHOULD BE RIGHT AROUND
70 AND IN THE LOWER 70S TUESDAY NIGHT. IN ADDITION...RAIN
CHANCES CONTINUE NEAR 40 PERCENT TUESDAY NIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
THE GFS AND ECMWF APPEAR TO BE IN PRETTY GOOD AGREEMENT
WEDNESDAY THROUGH SUNDAY. THE MID-UPPER LEVEL TROUGH REMAINS
NEAR THE EAST COAST AT LEAST THROUGH FRIDAY...THEN AN UPPER
RIDGE TO THE WEST TRIES TO NUDGE IN FOR THE WEEKEND. HOWEVER
THERE APPEARS TO BE A CHANCE OF SHOWERS AND THUNDERSTORMS
EACH DAY. THE HIGHEST CHANCES ARE EARLY IN THE PERIOD
WEDNESDAY THROUGH FRIDAY WITH A 30-40 PERCENT CHANCE. AS
THE UPPER RIDGE TRIES TO BUILD EAST...RAIN CHANCES DROP
A BIT TO 20-30 PERCENT FOR SATURDAY AND SUNDAY AND THE
CONVECTIVE ACTIVITY SHOULD BECOME MORE DIURNAL OR SUMMER
LIKE IN NATURE. HIGHS ARE A BIT BELOW NORMAL MAINLY IN
THE MIDDLE 80S WEDNESDAY AND THURSDAY BUT INCREASE TO
THE UPPER 80S BY SATURDAY AND SUNDAY BUT THERE MAY BE
A FEW 90S AROUND SUNDAY DEPENDING ON THE AMOUNT OF SUNSHINE.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
ONGOING TAF PACKAGE CONTINUES TO LOOK FINE.
SCT/BKN CU/SCU WITH VFR BASES CURRENTLY AT OUR TERMINALS.
LATEST LAPS/RUC SOUNDINGS CONTINUE TO INDICATE MID LEVEL CAP.
THIS...ALONG WITH SOME NVA BEHIND A DEPARTING WEAK SHORT WAVE...
PREVENTING CONVECTION OVER OUR FORECAST AREA (FA). MORE MOISTURE TO
OUR WEST CONTRIBUTING TO A FEW SHOWERS OVER NW GA. A WEAK UPPER
IMPULSE MAY PROVIDE SOME SHOWER ACTIVITY EASTWARD INTO NE GA/UPSTATE
SC LATE TODAY AND THIS EVENING...BUT EXPECT IT TO REMAIN NORTH OF
OUR TERMINALS. CURRENT DEWPOINTS OVER OUR FA RUNNING ABOUT 7-8
DEGREES HIGHER THAN YESTERDAY...WHICH WOULD PROVIDE SOME CONCERN
OVER RADIATION FOG POTENTIAL FOR LATE TONIGHT/EARLY MONDAY.
HOWEVER...BUFKIT INDICATES A 25 KNOT BOUNDARY LAYER FLOW DEVELOPING
FROM THE SW...WHICH WOULD WORK AGAINST FOG FORMATION...BUT COULD
CONTRIBUTE TO SOME STRATUS FORMATION...THOUGH A SW DIRECTION IS
TYPICALLY NOT THE MOST FAVORABLE DIRECTION FOR STRATUS. LATEST MOS
BULLETINS AND GFS LAMP SUGGESTING SOME STRATUS POSSIBLE...WITH
MAINYL MVFR CIGS. LAMP ALSO INDICATING MVFR VSBY POTENTIAL AT FOG
PRONE AGS/OGB. LATEST RAP SUGGESTING IFR CIG POTENTIAL AT
DNL/AGS...WITH NO RESTRICTIONS ELSEWHERE. FOR NOW...WILL MAINTAIN
MENTION OF MVFR CONDITIONS LATE TONIGHT/EARLY MONDAY. AFTER ANY
MORNING RESTRICTIONS...VFR EXPECTED MONDAY OUTSIDE OF ANY
CONVECTION. A DEEPENING UPPER TROUGH AND INCREASING ATMOSPHERIC
MOISTURE IS EXPECTED TO LEAD TO SCATTERED THUNDERSTORMS MONDAY
AFTERNOON...MAINLY AFTER 18Z.
EXTENDED AVIATION OUTLOOK...CHANCE OF MAINLY AFTERNOON/EVENING
THUNDERSTORMS. CHANCE OF LATE NIGHT/EARLY MORNING FOG/STRATUS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
328 PM CDT SUN JUN 16 2013
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 326 PM CDT SUN JUN 16 2013
TRICKY FORECAST FOR THE FIRST 12-24 HOURS WITH MANY FACTORS IN PLAY
FOR CONVECTION POTENTIAL...AND DIFFERENCES IN GUIDANCE AS TO
HOW/WHERE/WHEN STORMS EVOLVE. CURRENTLY VERY LITTLE CIN OVER THE
FORECAST AREA WITH AN AREA OF GENERALLY 1500-2000J/KG CAPE BISECTING
THE FA FROM NW TO SE. BULK SHEAR HOWEVER IS QUITE LOW...LESS THAN
10KTS WITHIN THE FIRST 15KFT PER NAM SOUNDINGS. PER CU FIELD ON
VISIBLE AND WINDS IN OBS WOULD APPEAR THAT BOUNDARY HAS MADE IT
SOUTH OF EMPORIA...WITH SOME WEAK WIND CONVERGENCE JUST SOUTH. NOT
CONFIDENT OF DEVELOPMENT ON THIS BOUNDARY BUT WILL LEAVE A SLIGHT
CHANCE SOUTH AND WEST TO ACCOUNT FOR PROBABILITY.
STARTING TO SEE CONVECTION DEVELOP IN SW NEBRASKA AS WELL AS FAR SW
SOUTH DAKOTA AT THIS HOUR. MOISTURE AXIS AND CORFIDI VECTORS
INDICATE THESE STORMS WOULD MOVE TO THE EAST TO SOUTHEAST WITH
TIME...BECOMING A CLUSTER AND MOVING ACROSS WESTERN AND PORTIONS OF
CENTRAL KANSAS. HOW FAR EASTWARD THEY CAN DEVELOP IS IN
QUESTION...WITH THE NAM/GFS/EC TAKING THE BRUNT OF THE QPF MAINLY
WEST OF OUR FORECAST AREA. LAST FEW RUNS OF THE HRRR BRING A SQUALL
LINE ACROSS MUCH OF THE FORECAST AREA GENERALLY 9PM TO AFTER
MIDNIGHT. THINK THE EARLIER SCENARIO IS MORE LIKELY AND WILL TAKE
MOST OF THE LLJ ENERGY INTO THE WESTERNMOST STORM COMPLEX...THINKING
WON`T BE ABLE TO DEVELOP A LINE OF STORMS FURTHER EAST BACK TOWARD
THE COOLER AIR. ONCE AGAIN WILL GO WITH CHANCE POPS TO THE WEST AND
DECREASE CHANCES EAST...BUT NOT WILLING TO TAKE POPS OUT FAR EAST
JUST YET GIVEN MODEL DIFFERENCES. ENOUGH INSTABILITY WITH A LINE OF
STORMS TO MAKE WIND AND HEAVY RAIN A CONCERN...BUT SHEAR PROFILES
NOT AS FAVORABLE FOR LOW LEVEL ROTATION. STORMS MOVE EASTWARD
QUICKLY AND HAVE A DRY FORECAST ALL AREAS BY AFTERNOON. HAVE LOWS IN
THE 60S TONIGHT WITH HIGHS IN THE 80S ON MONDAY...COOLER SE WHERE
CLOUDS AND RAIN MAY LINGER A FEW HOURS INTO THE MORNING MONDAY. 67
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 326 PM CDT SUN JUN 16 2013
MID RANGE AND EXTENDED FORECAST (TUESDAY THROUGH SUNDAY)...
EXPECT LARGE SCALE RIDGING TO TAKE PLACE IN THE MID RANGE TO
EXTENDED PERIOD OF THE FORECAST...WHICH WILL LIKELY SPELL A
CONSISTENT PERIOD OF ABOVE NORMAL TEMPERATURES THROUGH THE END OF
THE WORK WEEK AND THROUGH NEXT THE WEEKEND. HIGHS WILL LIKELY
REACH THE MID TO UPPER 90S...HOWEVER AS THAT TIME PERIOD
APPROACHES AND MODELS CONTINUE CONSISTENCY IN BRINGING IN THE MID
LEVEL RIDGE PERHAPS WE COULD SEE TEMPERATURES LATE IN THE WEEK AND
THIS WEEKEND REACH THE TRIPLE DIGIT MARK...ESPECIALLY IN THE
WESTERN ZONES WHERE MOISTURE COULD BE A LITTLE HARDER TO COME BY.
PRECIP CHANCES THROUGH THE EXTENDED WILL BE TOUGH TO NAIL
DOWN...AS THERE ARE NO REAL STRONG MID LEVEL SIGNALS TO REALLY
TRACK FOR PRECIP. THE BEST CHANCE FOR PRECIP DOES LOOK LIKE IT
WILL TAKE PLACE IN THE MID TO LATE PART OF THE WEEK AS MODELS HINT
AT SOME STRONG CONVECTION TAKING PLACE OFF THE HIGH PLAINS...AND
DRAGGING THE CONVECTION EASTWARD THROUGH THE CENTRAL PLAINS. THE
POSITION OF THE MID LEVEL TROUGH AND THE SUBSEQUENT STEERING FLOW
WILL LIKELY DETERMINE THE EXACT TRACK OF THE PRECIP. SHOULD THE
RIDGE BECOME LESS AMPLIFIED THE W-SW STEERING FLOW MAY END UP OVER
THE FORECAST AREA...HOWEVER SHOULD THE RIDGE BE A LITTLE STRONGER
THAN ANTICIPATED IT WOULD SHUNT THE CONVECTION NORTH. EITHER
WAY...WILL MAINTAIN CHANCE POPS FOR THE WED NIGHT THROUGH FRIDAY
TIME FRAME FOR THESE SHOWERS. OTHERWISE...THE MAINLY DRY AND WARM
FORECAST DESCRIBED ABOVE WILL BE EXPECTED THROUGH THE EXTENDED.
JL
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1235 PM CDT SUN JUN 16 2013
STILL NOT CERTAIN CONVECTION WILL DEVELOP AND MOVE OVER THE
INDIVIDUAL TAF SITES. AREA REMAINS RIPE FOR CONVECTION IF A WAVE
OR A BOUNDARY CAN MAKE IT INTO EASTERN KS AND WILL CONTINUE WITH
THE VCTS AT THIS TIME. MVFR CIGS SHOULD BREAK UP IN THE NEXT HOUR
OR SO WITH DAYTIME HEATING.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...67
LONG TERM...LEIGHTON
AVIATION...67
AREA FORECAST DISCUSSION
NWS WICHITA KS
314 PM CDT SUN JUN 16 2013
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 311 PM CDT SUN JUN 16 2013
A RATHER COMPLICATED SCENARIO IS UNDERWAY ACROSS THE CENTRAL PLAINS
THIS AFTERNOON. AN OUTFLOW BOUNDARY WAS LOCATED ACROSS CENTRAL
KANSAS FROM NEAR KHUT EXTENDING NORTH AND WEST TOWARD NORTON KANSAS
AT 2 PM CDT. CU HAS DEVELOPED ON THE COOL SIDE OF THIS OUTFLOW
BOUNDARY WHILE THE OPERATIONAL ECM RAP SHOWS MINIMAL CINH WITHIN AN
AXIS OF 2000-2500 J/KG. THIS BOUNDARY MAY BECOME A FOCUS FOR DEEP
MOIST CONVECTION BY LATE AFTERNOON. ANOTHER DIFFUSE OUTFLOW BOUNDARY
WAS SITUATED NEAR THE OKLAHOMA STATE LINE WHERE WIDELY SCATTERED
SHOWERS AND THUNDERSTORMS WILL REMAIN POSSIBLE ESPECIALLY SOUTH OF
THE STATE LINE. FURTHER NORTH AND WEST ANOTHER OUTFLOW BOUNDARY WAS
SURGING SOUTH ACROSS WESTERN NEBRASKA WHILE HIGH-BASED THUNDERSTORMS
WERE DEVELOPING ACROSS THE FRONT RANGE DOWNSTREAM OF A PV ANOMALY
TRANSLATING EASTWARD ACROSS THE CENTRAL ROCKIES. THE LATEST 12Z
SUITE OF MODEL DATA HAS SHIFTED THE QPF AXIS A BIT FURTHER WEST
TONIGHT...HOWEVER THIS AREA REMAINS OVERTURNED FROM DEEP MOIST CONVECTION
LAST NIGHT/EARLY TODAY. ANY ACTIVITY DEVELOPING ALONG THE OUTFLOW
BOUNDARY ACROSS CENTRAL KANSAS WOULD BE STEERED TOWARD SOUTH CENTRAL
KANSAS THIS EVENING WHILE ANOTHER LINE OF SHOWERS AND THUNDERSTORMS
MAY PROPAGATE SOUTHEASTWARD OFF THE HIGH PLAINS OF WESTERN KANSAS
LATE TONIGHT WHILE MERGING WITH THE ACTIVITY DRIFTING SOUTH OUT OF
NEBRASKA. WILL MAINTAIN HIGH POPS ACROSS MUCH OF CENTRAL/SOUTH
CENTRAL KANSAS TONIGHT WHILE THE THREAT FOR FLOODING OVER SOUTHEAST
KANSAS APPEARS TO HAVE DIMINISHED SLIGHTLY...HOWEVER NO PLANS TO
REMOVE THE FLOOD WATCH AT THIS TIME GIVEN RAINFALL AMOUNTS BETWEEN
2-3 INCHES A FEW LOCATIONS.
MAINTAINED POPS ACROSS MAINLY SOUTHEAST KANSAS THROUGH EARLY
AFTERNOON ON MONDAY WITH SOME TIMING DIFFERENCES...HOWEVER BY LATE
AFTERNOON TEMPERATURES ARE EXPECTED RECOVER INTO THE LOW TO MID 80S
WITHIN A STABLE AIRMASS BEHIND THE DEPARTING MCS. THERE IS SOME
CONCERN FOR CONTINUED OVERNIGHT CONVECTION MOVING EASTWARD OFF THE
HIGH PLAINS MONDAY NIGHT AND AGAIN ON TUESDAY NIGHT ACROSS MAINLY
CENTRAL KANSAS. HOWEVER BETTER CHANCES FOR DEEP MOIST CONVECTION MAY
ARRIVE TOWARD THE MIDDLE OF THE WEEK AS A MORE ROBUST SHORTWAVE
TROUGH MOVES OVER THE CENTRAL AND NORTHERN PLAINS. SEASONABLE
TEMPERATURES ARE EXPECTED THROUGH THE PERIOD WITH HIGHS IN THE 80S
AND LOW IN THE 60S. -MCGUIRE
.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 311 PM CDT SUN JUN 16 2013
LINGERING SHOWERS AND THUNDERSTORMS ARE POSSIBLE FOR THE EASTERN
THIRD OF KANSAS ON THURSDAY AS A SHORTWAVE EXITS THE AREA. A RIDGE
OVER THE CENTRAL U.S. WILL STAY PLANTED FOR MOST OF THIS TIME FRAME
WITHOUT A BREAKDOWN IN THE FLOW PATTERN UNTIL LATE IN THE WEEKEND
WHEN A TROUGH MOVES OVER THE NORTHERN U.S. THERE IS MODEL
DISAGREEMENT IN THE LOCATION AND TIMING OF A WAVE AHEAD OF THE MAIN
TROUGH. THUS ANY IMPACT TO THE AREA COULD ONLY BE CONSIDERED
PRELIMINARY AT THIS TIME. THE RIDGE IN PLACE WILL HELP SET THE STAGE
FOR TEMPERATURES CLIMBING ABOVE 90 ONCE MORE. -JUANITA
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 105 PM CDT SUN JUN 16 2013
MAIN AVIATION CONCERNS WILL BE TIMING AND EVOLUTION OF CONVECTIVE
CHANCES THIS AFTERNOON AND TONIGHT. TWO AREAS OF CONCERN LATE THIS
AFTERNOON. INITIAL CHANCES WILL BE ALONG REMNANT OUTFLOW BOUNDARIES
CURRENTLY OVER CEN KS AND ANOTHER JUST NORTHWEST OF KCNU. AFTERNOON
DIURNAL HEATING COULD LEAD TO A CHANCE OF TSRA IN AND NEAR THE KRSL
AND KCNU TAF SITES. SO WILL WITH A VCTS FOR LATE THIS AFTERNOON FOR
THIS CHANCE.
NEXT CONCERN WILL BE CONVECTION LATE THIS EVENING EXPECTED TO
CONGEAL INTO A COMPLEX OF TSRA OVER THE HIGH PLAINS. THIS COMPLEX
IS EXPECTED TO PUSH EAST-SOUTHEAST INTO SOUTH CEN AND CEN KS LATE
THIS EVENING AND OVERNIGHT. SO WILL GO WITH VCTS INITIALLY AROUND
03-04Z/MON...AND GO WITH PREVAILING TSRA 06Z/MON FOR THE KRSL AND
KHUT/KICT TAFS AS THIS SYSTEM MOVES ACROSS THE AREA. WILL ALSO GO
WITH SOME VARIABLE GUSTY WINDS OF 25G235KT AS THIS SYSTEM MOVES
THROUGH AS WELL.
KETCHAM
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 67 85 64 84 / 80 60 10 10
HUTCHINSON 67 85 63 84 / 80 50 10 10
NEWTON 67 84 63 83 / 70 50 10 10
ELDORADO 67 84 63 83 / 70 50 10 10
WINFIELD-KWLD 68 85 65 84 / 80 60 10 10
RUSSELL 65 85 61 84 / 70 20 20 10
GREAT BEND 65 86 62 84 / 70 20 20 10
SALINA 66 85 62 84 / 60 20 10 10
MCPHERSON 66 85 62 83 / 80 40 10 10
COFFEYVILLE 68 83 65 85 / 70 70 10 10
CHANUTE 68 84 63 84 / 60 70 0 0
IOLA 68 83 62 83 / 60 60 0 0
PARSONS-KPPF 68 83 64 84 / 70 70 10 0
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH FROM 7 PM CDT THIS EVENING THROUGH MONDAY AFTERNOON
FOR KSZ071-072-094>096-098>100.
&&
$$
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
315` PM EDT SUN JUN 16 2013
.SHORT TERM (Fathers Day through Monday Evening Night)...
Issued at 300 PM EDT Sun Jun 16 2013
Well...I have primarily focused on POPS and weather to hone on the
best opportunities for pcpn. 1st wave of pcpn is ahead of a cold
front located from BMG to MVN. Meanwhile warm sector pcpn developing
in better instability acrs S Central KY. Storms acrs the S have 1500
j/KG to work and a deep moisture plume above. These will make
for a few gully washers with some gusty winds below. Some strong
storms in Green county right now.
The main area of precip is moving to the E-SE and will bring likely
to categorical pops acrs S IN and N Central KY later afternoon
through mid evening. The NAM is handling the pcpn initialization
quite well and moving pcpn filed to the SE makes sense. The GFS is
much more aggressive and extensive pcpn fields. The high resolution
models are all over the place over the next 18 hours with the ARW,
HRRR, SPC WRF etc. all having various solutions with the wx scenario.
Overall, have cut back pops tonight in all except Sr Tier counties.
The cold front currently located from Lake Erie to near STL will
slide SE tonight to SRN IN by 12z Monday. Model soundings show low
level clouds encompassing the Srn IN counties Monday morning, so
have cut back pops significantly with except of the srn tier again
where better instability and moisture exists.
On Monday, took the POPS out of SR IN in the morning and then with
ill defined front nearby have slgt chc of storms in the afternoon.
For the S KY counties coordinated with PAH and have high end chance
pops to low end likely pops with better MUCAPE and theta e
advection. The POPS will increase as the day moves along especially
across SW CWA.
Made minor tweaks w.r.t. temps, except for Monday where I decreased
high temps due to cloud cover. MOS guidance has upper 80s and with
cloud cover mid 80s looks more realistic.
.LONG TERM (Monday Night through Sunday)...
Issued at 300 PM EDT Sun Jun 16 2013
Monday Night through Tuesday...
Forecast confidence is not what it was just 12 hrs ago, but still
looks like a period of unsettled weather Monday night through at
least Tuesday as two impulses will sweep through in the cyclonically
curved flow aloft. Confidence is limited by uncertainty in the
timing of these disturbances, and the deeper moisture being
suppressed just to our south.
Will begin Monday evening with likely POPs across the southern tier,
tapering down to slight chance in southern Indiana. Precip chances
will expand northward later in the evening as the upper disturbance
scoots through. Best chances will be a few hours either side of
midnight, in line with the GFS solution which is a bit more robust
than the NAM and slower than the ECMWF. Still not too excited about
severe weather given weak dynamics and instability that is marginal
at best, but a juicy atmosphere will support heavy rainfall as the
main hazard.
One more shortwave to swing through on Tuesday, so the POPs will
continue as the moisture lingers. Slight chance over Indiana, but
40-50 POP from the southern tier up into the Bluegrass region where
there is more juice to work with.
Diurnal temp ranges will be limited by clouds and moisture. Min
temps split the difference between model guidance numbers, while
highs will be on the low end of consensus.
Tuesday night through Sunday...
Surface high over the Great Lakes and upper ridge building from the
southwest will bring drier weather with temps near climo and lower
humidity on Wednesday and Thursday. Warmer and more humid air will
return later in the week as southerly low-level flow develops and
the upper ridge continues to build in from Texas. Temps will push 90
Friday through Sunday, with lows either side of 70. With the ridge
axis extending more into the Mississippi Valley, there remains the
possibility for convection to fire to our north and west, and move
into the Ohio Valley as it decays. Therefore will go with a somewhat
broad-brush 20 POP for a lot of the weekend.
&&
.AVIATION (12Z TAF Update)...
Issued at 1250 PM EDT Sun Jun 16 2013
Well...area of showers and storms is along from BMG to MVN to VIH.
This is moving at about 285 to 290 at 25 to 30 mph. The RUC and NAM
seem to be handing the radar trends the best and increase the precip
towards the SDF terminal late this afternoon.
The new models are strongly suggesting pushing the bulk of the
precip thru this evening and have a fairly dry day Monday except for
the BWG TAF site.
Even across the rain obs sites from IN-MO, VFR conditions dominate.
across the 3 sites here are the best times for pcpn:
SDF - 21-01z
LEX - 23-03z
BWG - 23z-05z and again on Monday
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Short Term.......JDG
Long Term........RAS
Aviation.........JDG
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1245 PM EDT SUN JUN 16 2013
...Updated Aviation Discussion...
.FORECAST UPDATE...
Issued at 1150 AM EDT Sun Jun 16 2013
Well...precipitation coverage has expanded in coverage out to the
west. IR imagery showing cooling cloud tops along and ahead of the
front across the Land of Lincoln into the Show Me State. Deeper
convection in the warm sector is developing across the Natural
State. Updated the grids to increase POPS to categorical across S IN
and likely north of the BG Parkway.
Early 12z Models showing southern push of precip with the front
later today and this evening. The NAM takes the pops out completely
for tomorrow. This is another vexing conundrum to deal with.
The BNA sounding has over 1000 J/kg and some mid level dry air. Some
of the early evening storms will have some gusty winds.
&&
.SHORT TERM (Today through Monday Night)...
Issued at 300 AM EDT Sun Jun 16 2013
...A bit of a challenging forecast today with regard to where and if
any scattered thunderstorms may develop...
An east-west elongated closed low across the Canadian plains has
pushed the polar jet a bit south across our northern tier of states.
In fact, at 500mb, some westerly zonal flow will move as far south
as the Lower Ohio Valley.
This flow has also pushed ample Gulf moisture northeast across
southern Illinois and Indiana, although locations along and south of
the Ohio River currently still are pretty dry, with PWATs still less
than one inch. Several convective complexes have crossed the midwest
earlier this morning, aided by the development of a nocturnal jet.
Once MCS, in particular is currently (at 2AM EDT) decaying over
central Indiana.
Moisture will increase today, especially along and north of the Ohio
River. Further complicating the matter, a weakening outflow boundary
will move southeast across southern Indiana during the pre-dawn
hours today.
So...for this morning, expect occasionally cloudy skies across
southern Indiana with perhaps some isolated sprinkles or very light
showers left over from the decaying MCS. Think that locations along
and south of Interstate 64 will stay dry this morning. Expect
partial clearing north and partly cloudy skies south this afternoon
with an increasing likelihood of scattered thunderstorms developing
by mid afternoon along and north of Interstate 64, with just
isolated storms farther south, away from any richer moisture or
potential outflow boundary.
Any isolated storms will diminish this evening with only a slight
chance for some lingering showers through Monday morning.
Model guidance has been very consistent in forecasting a flat 500mb
wave moving across the Commonwealth late Monday. After a dry
morning, think that at some point late Monday, convection will
become likely, especially across central and southern Kentucky. Both
The NAM and GFS have convective feedback problems across the
Commonwealth late Monday. However, do agree that some locally heavy
rain may develop across central Kentucky late Monday evening through
early Tuesday.
Highs today and Monday will not stray too far from the mid 80s.
.LONG TERM (Monday Night through Saturday)...
Issued at 313 AM EDT Sun Jun 16 2013
Monday Night through Tuesday Night...
Fairly unsettled weather pattern looks likely at the beginning of
the forecast period. At the surface, a quasi-stationary front is
forecast to be lying across the Ohio Valley. Aloft, a mid-level
vorticity maximum is progged to slide eastward into the Ohio Valley
Monday night. This feature should bring a period of shower and
thunderstorms to the region. Highest PoP chances look to be Monday
night and during the day on Tuesday as the upper level system pushes
through. Some of the storms could be on the strong side. However,
severe weather threat looks less with each successive model run. In
general, the bulk shear forecasts are weaker and the amount of cloud
cover and precipitation will likely result in lesser amounts of
instability. Nonetheless, a juicy atmosphere will be in place and
torrential rainfall, gusty winds and plenty of lightning look to be
the main storm threats. The period of unsettled weather looks to
end Tuesday night as the mid-level wave pushes off to the east and
surface high pressure builds in from the west/northwest.
Lows Monday night will be quite mild with readings in the upper 60s
to around 70. Highs Tuesday will largely be influenced by cloud
cover and precipitation. Latest blend of guidance suggests highs in
the upper 70s to the lower 80s in the east with lower 80s in areas
west of I-65. Lows Tuesday night should cool back into the middle
60s.
Wednesday through Saturday...
Surface high looks to remain in control of our weather through the
first part of the extended forecast period. Baggy upper trough is
expected to persist across the eastern US, with the deeper moisture
being confined to the southeastern US and just south of KY/IN.
Overall forecaster confidence is average during this period and it
appears that Wednesday and Thursday will be mostly dry across the
region. Temperatures will moderate during the period with highs on
Wednesday topping out in the lower-middle 80s. Highs should warm
back into the mid-upper 80s by Thursday...while overnight lows
remain in the 60s.
By late week, the models are suggesting that the heat ridge will
build up once again across the Plains states while the Ohio Valley
remains on the eastern periphery of the ridge. A southerly flow
will likely result in more moisture being advected northward into
the region by Friday resulting in isolated-scattered convection
developing during the afternoon/eve. With the region being on the
periphery of the upper ridge, we will need to monitor disturbances
tracking around the ridge as one or more of these disturbances may
result in MCS activity affecting the area by Saturday. Tracking and
timing these features at this time range is quite poor...so plan on
sticking to climatological PoPs with this forecast. Highs Friday
and Saturday will be close to seasonal normals with highs in the
85-90 degree range and overnight lows in the mid-upper 60s.
&&
.AVIATION (12Z TAF Update)...
Issued at 1250 PM EDT Sun Jun 16 2013
Well...area of showers and storms is along from BMG to MVN to VIH.
This is moving at about 285 to 290 at 25 to 30 mph. The RUC and NAM
seem to be handing the radar trends the best and increase the precip
towards the SDF terminal late this afternoon.
The new models are strongly suggesting pushing the bulk of the
precip thru this evening and have a fairly dry day Monday except for
the BWG TAF site. The 18z TAF account for this.
Even across the rain obs sites from IN-MO, VFR conditions dominate.
across the 3 sites here are the best times for pcpn:
SDF - 21-01z
LEX - 23-03z
BWG - 23z-05z and again on Monday
Winds will primarily stay SWLY and less than 10 mph.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Update...........JDG
Short Term.......JDG
Long Term........MJ
Aviation.........JDG
AREA FORECAST DISCUSSION
NWS GRAY ME
441 PM EDT SUN JUN 16 2013
.SYNOPSIS...
A WEAK AREA OF LOW PRESSURE WILL CROSS THE REGION THIS EVENING BRINGING
WIDESPREAD SHOWERS TO MOUNTAINS AND FOOTHILLS AND SCATTERED
SHOWERS ALONG THE COAST. A COLD FRONT ASSOCIATED WITH ANOTHER
AREA OF LOW PRESSURE PASSING TO OUR NORTH MONDAY WILL TRIGGER
SHOWERS AND THUNDERSTORMS ACROSS THE AREA MONDAY AFTERNOON. THE
FRONT WILL MOVE OFF THE COAST TUESDAY MORNING. HIGH PRESSURE WILL
BUILD IN FOR THE MIDDLE AND LATTER PART OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
UPDATE...
HAVE UPDATED GRIDDED FORECAST BASED ON CURRENT CONDITIONS. LATEST
RADAR ANIMATIONS CONTINUE TO SHOW AREAS OF RAIN OVER NH SPREADING
EAST INTO MAINE. WHILE SOME OF THIS IS DRYING UP WITH EVAP
COOLING...RAIN IS REACHING THE GROUND IN MANY AREAS. HAVE UPPED
POPS FOR SOUTHERN COUNTIES...ALBIET THE RAIN WILL BE VERY LIGHT.
LATEST HRRR RUN SHOWS MUCH OF THE PCPN EXITING ERN PORTIONS OF
MANIE BY ABOUT 01Z OR 02Z.
PREV DISC...
AREA OF SHOWERS CONTINUES TO MOVE EAST FROM NY STATE THIS
AFTERNOON. MUCH OF THE INITIAL PRECIP HAS BEEN EVAPORATING BEFORE
REACHING THE GROUND, ESPECIALLY IN SOUTHERN AREAS. AIR OVER MOUNTAINS
AND FOOTHILLS SHOULD SATURATE...SO EXPECT WIDESPREAD RAIN IN
THOSE AREAS THIS EVENING. ELSEWHERE...EXPECT ONLY SCATTERED
SHOWERS TO REACH THE GROUND AS AIR IS VERY DRY. PATCHY FOG
EXPECTED OVERNIGHT IN AREAS THAT GET A SHOWER THIS EVENING.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
FRONTAL BOUNDARY APPROACHES FROM THE WEST MONDAY WITH INCREASING
MOISTURE AND TEMPERATURES. AHEAD OF THE FRONT...TEMPS IN SOUTHERN
AREAS COULD REACH THE MID 80S. ATMOSPHERE BECOMES A BIT UNSTABLE
AHEAD OF THE FRONT BRINGING THE THREAT OF SHOWERS AND
THUNDERSTORMS TO THE AREA MONDAY AFTERNOON AND EVENING. FRONT
MOVES VERY THROUGH REGION WITH SHOWER THREAT CONTINUING MONDAY
NIGHT.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
FAIRLY QUIET EXTENDED PERIOD IN STORE. SHOULD BE A WEAK BOUNDARY
DRAPED ACROSS THE REGION TUESDAY MORNING THAT COULD PROVIDE A
FOCUS FOR SOME AFTERNOON CONVECTION. THE BOUNDARY IS EXPECTED TO
MOVE OFFSHORE TUESDAY NIGHT AS HIGH PRESSURE BUILDS IN FROM THE
WEST. HIGH PRESSURE THEN REMAINS IN PLACE ACROSS NORTHERN NEW
ENGLAND UNTIL AT LEAST FRIDAY. CYCLONIC FLOW ALOFT SETS UP OVER
THE REGION FRIDAY NIGHT. THE GFS IS TRYING TO DROP A WEAK BACK
DOOR COLD FRONT OUT OF CANADA FRIDAY NIGHT AND INTO SATURDAY BUT
APPEARS TO BE THE OUTLIER. WILL NOT GIVE IT TOO MUCH WEIGHT YET
BUT IT WILL REMAIN A FEATURE TO LOOK FOR OVER THE NEXT FEW DAYS.
&&
.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
SHORT TERM...MVFR CONDITIONS POSSIBLE TONIGHT IN SHOWERS AND IFR
CONDITIONS POSSIBLE IN PATCHY FOG OVERNIGHT. MVFR TO IFR
CONDITIONS POSSIBLE IN SHOWERS AND THUNDERSTORMS MONDAY AFTERNOON
AND NIGHT.
LONG TERM...VFR CONDITIONS EXPECTED THROUGHOUT THE PERIOD.
&&
.MARINE...
SHORT TERM...WINDS AND SEAS EXPECTED TO BE BELOW SCA CRITERIA.
LONG TERM...NO FLAGS EXPECTED.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
342 PM EDT SUN JUN 16 2013
.SYNOPSIS...
A FRONTAL BOUNDARY WILL SAG SOUTHEASTWARD INTO THE AREA
TONIGHT...BRINGING SHOWERS AND POSSIBLY AN ISOLATED THUNDERSTORM
INTO MONDAY...WITH A LOW CHANCE OF SHOWERS THROUGH THIS PERIOD. THE
FRONT WILL PUSH SOUTHEAST OF THE AREA LATE ON TUESDAY AND HIGH
PRESSURE WILL THEN BUILD IN FROM THE NORTHWEST AND ALLOW FOR A DRY
MID-WEEK.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
THE LATEST RAP UPPER LEVEL ANALYSIS INDICATES THE UPPER OHIO
VALLEY IN A ZONAL FLOW WITH A 300MB 100KT JET AXIS CENTERED OVER
SOUTHERN ONTARIO. AT THE MID-LEVELS...A 500MB SHORT WAVE IS WEAKENING
AS IT SHIFTS INTO CENTRAL PA. AT THE SURFACE...A 1004MB SURFACE
LOW IS LOCATED NORTH OF LAKE SUPERIOR WITH A ILL- DEFINED FRONTAL
BOUNDARY EXTENDING SOUTH OF THIS FEATURE INTO NORTHERN OHIO.
SHOWERS INITIALLY ASSOCIATED WITH THE MID-LEVEL WAVE HAVE MOSTLY
DIMINISHED AND SHIFTED EAST OF THE AREA.
THIS EVENING...THE FRONTAL BOUNDARY WILL SAG SOUTHEASTWARD INTO
THE AREA. EXTENSIVE UPSTREAM CLOUD COVERAGE WILL CONTINUE TO
MOSTLY LIMIT CONVECTIVE TEMPS FROM BEING REACHED. THUS...HAVE GONE WITH
SCATTERED SHOWERS AND ISOLATED THUNDERSTORM WORDING TO NOT
COMPLETELY DISCOUNT THE HRRR/WRF-NMM SOLUTIONS WHICH INDICATE A
CLUSTER OF SHOWERS AND THUNDERSTORMS DEVELOPING. WITH ALL OF THIS IN
MIND...THE STORM PREDICTION CENTER STILL HAS THE AREA MENTIONED IN
ITS SEE TEXT. TEMPS HAVE BEEN LOWERED A FEW DEGREES CLOSER TO
LAMP GUIDANCE...WITH HIGHS RANGING FROM THE LOWER TO MID 70S
ACROSS THE AREA.
TONIGHT...THE FRONTAL BOUNDARY WILL CONTINUE TO EDGE SOUTHEASTWARD
ACROSS THE AREA...WITH ANY LINGERING COVERAGE OF SHOWERS MOSTLY
DIMINISHING BY 06Z. MOSTLY CLOUDY SKIES WILL BEGIN TO GIVE WAY TO
MORE BREAKS IN CLOUD COVERAGE WITH SHOWERS COMING TO AN END AS A
POCKET OF DRIER AIR ADVECTS IN FROM THE NORTHWEST. CLOUD COVERAGE
FOR MUCH OF THE NIGHT WILL SERVE TO MODERATE LOW TEMPS. FORECAST
IS CLOSEST TO THE WARMER MAV...WITH LOWS RANGING FROM THE LOWER TO
MID 60S ACROSS THE AREA.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/...
GFS/ECMWF SOLUTIONS ARE IN AGREEMENT THAT THE UPPER OHIO VALLEY WILL
CONTINUE TO BE IN A ZONAL MID-LEVEL FLOW ON MONDAY WITH THE POORLY
DEFINED SURFACE FRONTAL BOUNDARY BECOMING NEARLY STATIONARY NEAR
THE MASON-DIXON LINE. WITH THE BOUNDARY SERVING AS A FOCAL POINT
FOR POSSIBLE AFTERNOON CONVECTION...HAVE LEFT THE SLIGHT CHANCE OF
THUNDERSTORMS IN THE FORECAST FOR MONDAY. HIGHS ON MONDAY ARE A
FEW DEGREES ABOVE GFS/NAM/ECMWF GUIDANCE...RANGING FROM THE UPPER
70S ACROSS THE ALLEGHENY FRONT TO THE MID 80S IN EASTERN OHIO.
ON MONDAY NIGHT...POP FORECAST INCREASES TO CHANCE AS THE ECMWF
INDICATES A WAVE MOVING IN FROM THE WEST. STILL QUITE A BIT OF
UNCERTAINTY IN THE TIMING OF SHOWERS IN A ZONAL FLOW. DESPITE THE
FRONTAL BOUNDARY MOVING SOUTHEASTWARD ON MONDAY NIGHT...WEAK
ISODROSOTHERMAL GRADIENT WILL ALLOW TDS TO REMAIN IN THE UPPER 50S
TO LOWER 60S AND THUS LOWS ARE A ECMWF/NAM BLEND IN THE LOWER 60S
ACROSS MUCH OF THE AREA.
WEAK SHORT WAVE VORT ENERGY WILL MOVE ACROSS THE AREA ON TUESDAY AS
THE AREA IS IN MORE OF A WEAK MID-LEVEL CYCLONIC FLOW ASSOCIATED
WITH A BROAD TROUGH IN SERN CANADA. THE GFS IS INDICATING WEAK
INSTABILITY (SBCAPE <1000 J/KG) WITH MODERATE SHEAR (0-6KM BULK
SHEAR 30-35KTS) DURING THE PASSAGE OF THE WAVE. THE NAM TAKES A MUCH
MORE AGGRESSIVE APPROACH WITH THE CONVECTIVE ENVIRONMENT THAT IS CURRENTLY
BEING DISCOUNTED. THE FORECAST LEANS CLOSER TO THE GFS...WITH THE
CHC OF SHOWERS AND THUNDERSTORMS ACROSS THE AREA. AT THIS
TIME...AM NOT ANTICIPATING A SEVERE THREAT...BUT WILL CONTINUE
MONITOR THIS DUE TO THE FACT THAT IF THE NAM SOLUTION IS REALIZED
A FEW STRONG TO SEVERE STORMS WILL BE POSSIBLE. WITH THE LOSS OF
HEATING AND THE BOUNDARY SLIDING SOUTHEAST OF THE AREA...THE
FORECAST WILL BECOME DRY TUESDAY NIGHT.
HIGH PRESSURE ALONG WITH A DEEP LAYER OF DRY AIR WILL BUILD IN FROM
THE NORTHWEST ON WEDNESDAY AND ALLOW FOR A BREAK FROM SHOWERS AND
THUNDERSTORMS WITH MOSTLY SUNNY SKIES. DESPITE THE ABUNDANT SUNSHINE
ANTICIPATED...COOLER/DRIER AIR MASS WILL LIMIT HIGH TEMPS TO A FEW
DEGREES BELOW NORMAL.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
LATEST GFS AND ECMWF DETERMINISTIC SOLNS AGREED GENLY IN
DEPICTIONS OF THE PROGGED FLOW PTN OVR THE ERN CONUS FOR THE
LATTER HALF OF THE WEEK...WITH ECMWF AMPLIFYING THE PTN CLOSER TO
GFS WITH A RIDGE AXIS EXTENDING FM THE SRN PLNS ACRS THE GREAT
LAKES.
THE LONG TERM FORECAST THUS CONSERVATIVELY FEATURES TEMPS
GRADUALLY WARMING TO SLIGHTLY ABOVE THE SEASONAL AVERAGES BY THE
WEEKEND. PCPN CHCS WERE FORECAST AOB CLIMO NMBRS...BUT WERE GENLY
INCRSD USING A GFS/ECMWF BLEND FOR SHRTWV TIMING INTO THE WEEKEND.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
CURRENTLY GENERAL MVFR CONDITIONS AT MOST SITES WITH RAIN
SHOWERS. GRADUALLY IMPROVING CONDITIONS CAN BE EXPECTED AS A WEAK
COLD FRONT CONTINUES MOVING SOUTHEAST THROUGH REGION. CIGS SHOULD
GRADUALLY IMPROVE TO VFR EVERYWHERE THIS EVENING WITH PARTIAL
CLEARING TONIGHT. SLIGHTLY DRIER AIR GRADUALLY MOVING IN BUT WITH
WET CONDITIONS OVER THE AREA AND DEWPOINTS ONLY DROPPING SLIGHTLY WILL
LIKELY SEE SOME FG/BR TO DEAL WITH MONDAY MORNING AT SOME TAF SITES.
.OUTLOOK.../MONDAY THROUGH FRIDAY/...
PERIODIC RESTRICTIONS ARE ANTICIPATED THROUGH TUESDAY AS ANOTHER
LOW APPRCHS AND CROSSES THE REGION. BLDG HIGH PRES SHOULD RTN VFR
CONDITIONS FOR WEDNESDAY THROUGH FRIDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
SYNOPSIS...WOODRUM
NEAR TERM...WOODRUM
SHORT TERM...WOODRUM
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
234 PM EDT SUN JUN 16 2013
.SYNOPSIS...
A WEAK DISTURBANCE WILL PUSH EAST OF THE AREA TODAY...BRINGING SHOWERS
AND POSSIBLY AN ISOLATED THUNDERSTORM. A FRONTAL BOUNDARY WILL SAG
SOUTHEASTWARD INTO THE AREA TONIGHT INTO MONDAY...WITH A LOW
CHANCE FOR SHOWERS THROUGH THIS PERIOD. THE FRONT WILL PUSH
SOUTHEAST OF THE AREA LATE ON TUESDAY AND HIGH PRESSURE WILL THEN
BUILD IN FROM THE NORTHWEST AND ALLOW FOR A DRY MID-WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
18Z ENHANCED SHORT TERM FORECAST HAS BEEN ISSUED TO REDUCE POPS AS
INITIAL WAVE OF SHOWERS PUSHES EAST OF THE AREA.
THE LATEST RAP UPPER LEVEL ANALYSIS INDICATES THE UPPER OHIO VALLEY
IN A ZONAL FLOW WITH A 300MB 100KT JET AXIS CENTERED OVER LAKE
HURON. AT THE MID-LEVELS...A 500MB SHORT WAVE IS WEAKENING AS IT
MOVES EASTWARD INTO WESTERN PA. AT THE SURFACE...A 1005MB SURFACE
LOW IS LOCATED NORTH OF LAKE SUPERIOR WITH A ILL-DEFINED FRONTAL
BOUNDARY EXTENDING SOUTH OF THIS FEATURE ACROSS SOUTHERN MICHIGAN.
WELL AHEAD OF THE FRONT...WEAK 700-500MB VORT ENERGY ALONG WITH A
MOIST 800-650MB LAYER ARE SUPPORTING SCATTERED SHOWERS MOVING
EAST OF THE AREA.
THIS AFTERNOON AND EVENING...THE SHORT WAVE WILL CONTINUE TO
WEAKEN AS IT MOVES INTO CENTRAL PENNSYLVANIA. MEANWHILE...THE
FRONTAL BOUNDARY WILL SAG FURTHER SOUTHEASTWARD INTO THE AREA. AS
FORCING FROM THE WAVE MOVES EASTWARD...SHOWERS WILL DIMINISH IN
COVERAGE. EXTENSIVE UPSTREAM CLOUD COVERAGE WILL CONTINUE TO
INHIBIT CONVECTIVE TEMPS FROM BEING REACHED. THUS...HAVE GONE WITH
CHC SHOWERS AND SCHC THUNDERSTORM WORDING TO NOT COMPLETELY DISCOUNT
THE HRRR/WRF-NMM SOLUTIONS. WITH ALL OF THIS IN MIND...THE STORM
PREDICTION CENTER STILL HAS THE AREA MENTIONED IN ITS SEE TEXT.
TEMPS HAVE BEEN LOWERED A FEW DEGREES CLOSER TO LAMP
GUIDANCE...WITH HIGHS RANGING FROM THE LOWER TO MID TO UPPER 70S
ACROSS THE AREA.
TONIGHT...THE FRONTAL BOUNDARY WILL CONTINUE TO SAG SOUTHEASTWARD
ACROSS THE AREA...WITH ANY LINGERING COVERAGE OF SHOWERS MOSTLY
DIMINISHING BY 06Z. MOSTLY CLOUDY SKIES WILL BEGIN TO GIVE WAY TO
MORE BREAKS IN CLOUD COVERAGE WITH SHOWERS COMING TO AN END AS A
POCKET OF DRIER AIR ADVECTS IN FROM THE NORTHWEST. CLOUD COVERAGE
FOR MUCH OF THE NIGHT WILL SERVE TO MODERATE LOW TEMPS. FORECAST IS
CLOSEST TO THE WARMER MAV...WITH LOWS RANGING FROM THE LOWER TO MID
60S ACROSS THE AREA.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
HAVE BACKED OFF POPS ON MONDAY DOWN TO SLIGHT CHANCE. FORECAST AREA
SHOULD BE IN THE DRY REGION BETWEEN FRONTS TO THE NORTH AND
SOUTH...AND DO NOT SEE MUCH OF A TRIGGER TO GET PRECIP GOING. MONDAY
NIGHT AND TUESDAY THE NAM/SREF ARE AGGRESSIVE SWEEPING THE NORTHERN
FRONT ACROSS THE REGION AND BRINGING WIDESPREAD PRECIPITATION. WITH
THE ECMWF SHOWING MORE CONSISTENCY...KEEPING THE NORTHERN FRONT DRY
AND FOCUSING PRECIPITATION ALONG THE SOUTHERN FRONT...AND THE GFS
AND GEFS COMING INTO LINE WITH THE ECMWF SOLUTION...HAVE BACKED OFF
POPS ACROSS THE NORTHERN HALF OF THE REGION FOR MON NIGHT/TUES.
ONCE THE FRONT MOVES OFF TO THE EAST...THE ENTIRE AREA SHOULD BE
DRY TUESDAY NIGHT AND WEDNESDAY WITH HIGH PRESSURE MOVING IN FROM
MICHIGAN. LIGHT NORTHERLY FLOW THROUGH THIS TIME PERIOD SHOULD
KEEP TEMPERATURES A FEW DEGREES BELOW NORMAL.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
LATEST GFS AND ECMWF DETERMINISTIC SOLNS AGREED GENLY IN
DEPICTIONS OF THE PROGGED FLOW PTN OVR THE ERN CONUS FOR THE
LATTER HALF OF THE WEEK...WITH ECMWF AMPLIFYING THE PTN CLOSER TO
GFS WITH A RIDGE AXIS EXTENDING FM THE SRN PLNS ACRS THE GREAT
LAKES.
THE LONG TERM FORECAST THUS CONSERVATIVELY FEATURES TEMPS
GRADUALLY WARMING TO SLIGHTLY ABOVE THE SEASONAL AVERAGES BY THE
WEEKEND. PCPN CHCS WERE FORECAST AOB CLIMO NMBRS...BUT WERE GENLY
INCRSD USING A GFS/ECMWF BLEND FOR SHRTWV TIMING INTO THE WEEKEND.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
CURRENTLY GENERAL MVFR CONDITIONS AT MOST SITES WITH RAIN
SHOWERS. GRADUALLY IMPROVING CONDITIONS CAN BE EXPECTED AS A WEAK
COLD FRONT CONTINUES MOVING SOUTHEAST THROUGH REGION. CIGS SHOULD
GRADUALLY IMPROVE TO VFR EVERYWHERE THIS EVENING WITH PARTIAL
CLEARING TONIGHT. SLIGHTLY DRIER AIR GRADUALLY MOVING IN BUT WITH
WET CONDITIONS OVER THE AREA AND DEWPOINTS ONLY DROPPING SLIGHTLY WILL
LIKELY SEE SOME FG/BR TO DEAL WITH MONDAY MORNING AT SOME TAF SITES.
.OUTLOOK.../MONDAY THROUGH THURSDAY/...
PERIODIC RESTRICTIONS ARE ANTICIPATED THROUGH TUESDAY AS ANOTHER
LOW APPRCHS AND CROSSES THE REGION. BLDG HIGH PRES SHOULD RTN VFR
CONDITIONS FOR WEDNESDAY AND THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
SYNOPSIS...WOODRUM
NEAR TERM...WOODRUM
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
150 PM EDT SUN JUN 16 2013
.SYNOPSIS...
A WEAK DISTURBANCE WILL CROSS THE REGION TODAY...BRINGING SHOWERS
AND POSSIBLY AN ISOLATED THUNDERSTORM. A FRONTAL BOUNDARY WILL SAG
SOUTHEASTWARD INTO THE AREA TONIGHT INTO MONDAY...WITH A LOW
CHANCE FOR SHOWERS THROUGH THIS PERIOD. THE FRONT WILL PUSH
SOUTHEAST OF THE AREA LATE ON TUESDAY AND HIGH PRESSURE WILL THEN
BUILD IN FROM THE NORTHWEST AND ALLOW FOR A DRY MID-WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
15Z ENHANCED SHORT TERM FORECAST HAS BEEN ISSUED TO INCREASE
POP...USING COVERAGE WORDING THROUGH THE EARLY AFTERNOON. IN
ADDITION...WITH EXTENSIVE CLOUD COVERAGE ACROSS THE OHIO
VALLEY...HAVE LOWERED HIGH TEMPS TODAY 1-2 DEGREES.
THE LATEST RAP UPPER LEVEL ANALYSIS INDICATES THE UPPER OHIO VALLEY
IN A ZONAL FLOW WITH A 300MB 100KT JET AXIS CENTERED OVER LAKE
HURON. AT THE MID-LEVELS...A 500MB SHORT WAVE IS WEAKENING AS IT
MOVES EASTWARD ACROSS OHIO. AT THE SURFACE...A 1005MB SURFACE LOW IS
LOCATED NORTH OF LAKE SUPERIOR WITH A ILL-DEFINED FRONTAL BOUNDARY
EXTENDING SOUTH OF THIS FEATURE ACROSS SOUTHERN MICHIGAN. WELL AHEAD
OF THE FRONT...WEAK 700-500MB VORT ENERGY ALONG WITH A MOIST
800-650MB LAYER ARE SUPPORTING SCATTERED SHOWERS MOVING ACROSS THE
AREA. THE 12Z KPIT SOUNDING SHOWS THE AFOREMENTIONED MOIST LAYER
WITH WEAK SBCAPE (APPROX 100 J/KG) WITH A UNIDIRECTIONAL ZONAL
PROFILE THROUGH MUCH OF THE COLUMN.
THIS AFTERNOON...THE SHORT WAVE WILL CONTINUE TO WEAKEN AS IT MOVES
INTO WESTERN PENNSYLVANIA AND THE FRONTAL BOUNDARY WILL SAG FURTHER
SOUTHEASTWARD INTO OHIO. FORCING FROM THE WAVE WILL ALLOW FOR
SCATTERED SHOWERS TO CONTINUE INTO THE EARLY AFTERNOON. SOME
UNCERTAINTY COMES INTO THE FORECAST IN THE 18Z-00Z WINDOW AS HIRES
MODEL SOLUTIONS VARY IN RESOLVING CONVECTION THIS AFTERNOON.
HRRR/WRF-NMM SUPPORT THE DEVELOPMENT OF THUNDERSTORMS ALONG THE
FRONTAL BOUNDARY WHILE THE NAM 4KM INDICATES SHOWERS MORE LIMITED.
WITH EXTENSIVE UPSTREAM CLOUD COVERAGE...BELIEVE THIS WILL INHIBIT
CONVECTIVE TEMPS FROM BEING REACHED. THUS...HAVE GONE WITH
SCATTERED/NUMEROUS SHOWERS AND ISOLATED THUNDERSTORM WORDING TO NOT
COMPLETELY DISCOUNT THE HRRR/WRF-NMM SOLUTIONS. WITH ALL OF THIS
IN MIND...THE STORM PREDICTION CENTER HAS MENTIONED THE AREA IN
ITS SEE TEXT...CONSIDERING THE LOW PROB SCENARIO THAT IF CLOUD COVERAGE
BREAKS THEN THE UNIDIRECTIONAL SHEAR ENVIRONMENT WOULD BE
FAVORABLE FOR A POSSIBLE EWD MOVING STRONG TO SEVERE CONVECTIVE
CLUSTER IN THE 18Z-00Z TIME FRAME. TEMPS HAVE BEEN LOWERED A FEW
DEGREES CLOSER TO LAMP GUIDANCE...WITH HIGHS RANGING FROM THE
LOWER TO MID 70S ACROSS THE AREA.
TONIGHT...THE FRONTAL BOUNDARY WILL CONTINUE TO SAG SOUTHEASTWARD
ACROSS THE AREA...WITH ANY LINGERING COVERAGE OF SHOWERS MOSTLY
DIMINISHING BY 06Z. MOSTLY CLOUDY SKIES WILL BEGIN TO GIVE WAY TO
MORE BREAKS IN CLOUD COVERAGE WITH SHOWERS COMING TO AN END AS A
POCKET OF DRIER AIR ADVECTS IN FROM THE NORTHWEST. CLOUD COVERAGE
FOR MUCH OF THE NIGHT WILL SERVE TO MODERATE LOW TEMPS. FORECAST IS
CLOSEST TO THE WARMER MAV...WITH LOWS RANGING FROM THE LOWER TO MID
60S ACROSS THE AREA.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
HAVE BACKED OFF POPS ON MONDAY DOWN TO SLIGHT CHANCE. FORECAST AREA
SHOULD BE IN THE DRY REGION BETWEEN FRONTS TO THE NORTH AND
SOUTH...AND DO NOT SEE MUCH OF A TRIGGER TO GET PRECIP GOING. MONDAY
NIGHT AND TUESDAY THE NAM/SREF ARE AGGRESSIVE SWEEPING THE NORTHERN
FRONT ACROSS THE REGION AND BRINGING WIDESPREAD PRECIPITATION. WITH
THE ECMWF SHOWING MORE CONSISTENCY...KEEPING THE NORTHERN FRONT DRY
AND FOCUSING PRECIPITATION ALONG THE SOUTHERN FRONT...AND THE GFS
AND GEFS COMING INTO LINE WITH THE ECMWF SOLUTION...HAVE BACKED OFF
POPS ACROSS THE NORTHERN HALF OF THE REGION FOR MON NIGHT/TUES.
ONCE THE FRONT MOVES OFF TO THE EAST...THE ENTIRE AREA SHOULD BE
DRY TUESDAY NIGHT AND WEDNESDAY WITH HIGH PRESSURE MOVING IN FROM
MICHIGAN. LIGHT NORTHERLY FLOW THROUGH THIS TIME PERIOD SHOULD
KEEP TEMPERATURES A FEW DEGREES BELOW NORMAL.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
LATEST GFS AND ECMWF DETERMINISTIC SOLNS AGREED GENLY IN
DEPICTIONS OF THE PROGGED FLOW PTN OVR THE ERN CONUS FOR THE
LATTER HALF OF THE WEEK...WITH ECMWF AMPLIFYING THE PTN CLOSER TO
GFS WITH A RIDGE AXIS EXTENDING FM THE SRN PLNS ACRS THE GREAT
LAKES.
THE LONG TERM FORECAST THUS CONSERVATIVELY FEATURES TEMPS
GRADUALLY WARMING TO SLIGHTLY ABOVE THE SEASONAL AVERAGES BY THE
WEEKEND. PCPN CHCS WERE FORECAST AOB CLIMO NMBRS...BUT WERE GENLY
INCRSD USING A GFS/ECMWF BLEND FOR SHRTWV TIMING INTO THE WEEKEND.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
CURRENTLY GENERAL MVFR CONDITIONS AT MOST SITES WITH RAIN
SHOWERS. GRADUALLY IMPROVING CONDITIONS CAN BE EXPECTED AS A WEAK
COLD FRONT CONTINUES MOVING SOUTHEAST THROUGH REGION. CIGS SHOULD
GRADUALLY IMPROVE TO VFR EVERYWHERE THIS EVENING WITH PARTIAL
CLEARING TONIGHT. SLIGHTLY DRIER AIR GRADUALLY MOVING IN BUT WITH
WET CONDITIONS OVER THE AREA AND DEWPOINTS ONLY DROPPING SLIGHTLY WILL
LIKELY SEE SOME FG/BR TO DEAL WITH MONDAY MORNING AT SOME TAF SITES.
.OUTLOOK.../MONDAY THROUGH THURSDAY/...
PERIODIC RESTRICTIONS ARE ANTICIPATED THROUGH TUESDAY AS ANOTHER
LOW APPRCHS AND CROSSES THE REGION. BLDG HIGH PRES SHOULD RTN VFR
CONDITIONS FOR WEDNESDAY AND THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
415 PM EDT SUN JUN 16 2013
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 411 PM EDT SUN JUN 16 2013
THE MAIN CONCERN FOR THE SHORT TERM FORECAST WILL BE THE ONGOING
SHOWERS AND THUNDERSTORMS AND ADDITIONAL SHOWERS WITH THE TROUGH
DROPPING SOUTH ACROSS THE AREA TONIGHT. INITIAL CONVECTION WAS OVER
EASTERN UPPER MICHIGAN...WHERE THERE WAS INCREASED MOISTURE FROM THE
FOG EARLIER TODAY AND CONVERGENCE FROM WEAK LAKE BREEZES. THESE
INITIAL SHOWERS HAVE SHIFTED TO THE SOUTHEAST AND OUT OF THE
CWA...BUT ARE SEEING SOME SHOWERS IN CENTRAL UPPER MICHIGAN ALONG
THE LAKE SUPERIOR LAKE BREEZE. THESE SHOWERS HAVE BEEN LIMITED THUS
FAR DUE TO THE DRY MID LEVEL AIR EVEN THOUGH THERE IS STRONG
LOW LEVEL LAPSE RATES AND RAP ANALYZED SB CAPE VALUES OF
500-1000 J/KG. BUT WITH THE INVERTED V LOOK TO THE RAP
SOUNDINGS...ML CAPES ARE STRUGGLING TO GET MUCH ABOVE 250-500 J/KG.
THIS DRY AIR CAN ALSO BE SEEN IN THE DEWPOINTS /UPPER 40S/ AWAY
FROM THE INFLUENCE OF THE GREAT LAKES. THERE HAVE EVEN BEEN SOME
SIGNIFICANT JUMPS IN THE DEWPOINTS OVER THE EASTERN CWA...AS THE
LAKE BREEZES HAVE MOVED IN AND OUT OF SOME OF THE SITES. FARTHER
WEST...A PERSISTENT SHOWER/THUNDERSTORM CLUSTER MOVED INTO WESTERN
GOGEBIC COUNTY OVER THE LAST HOUR AND DID PRODUCE SOME GUSTS UP TO
40KTS EVEN THOUGH THE CLUSTER IS DIMINISHING. THIS ISN/T TOO
UNREASONABLE WITH CURRENT DCAPE VALUES OVER MUCH OF UPPER MICHIGAN
AROUND 800-1000 J/KG AND THE INVERTED V SOUNDINGS. WOULD EXPECT
THIS TO BE THE PRIMARY CONCERN FOR ANY SHOWERS/THUNDERSTORMS LATE
THIS AFTERNOON AND EVENING. FINALLY...ADDITIONAL
SHOWERS/THUNDERSTORMS HAVE BEEN ONGOING JUST NORTHEAST OF LAKE
SUPERIOR...DUE TO ONE PIECE OF SHEARED OFF UPPER LEVEL ENERGY
DROPPING SOUTHEAST ALONG THE TROUGH. THESE SHOWERS WILL CONTINUE
QUICKLY SOUTHEAST AS THE STORM MOTION IS AROUND 40KTS.
THE AREA THAT WILL BRING THE BEST CHANCE FOR SHOWERS IS THE
REMNANT SHORTWAVE FROM THE UPPER LOW THAT WAS IN CENTRAL
SASKATCHEWAN YESTERDAY. THIS SHORTWAVE HAS STARTED TO MOVE TOWARDS
THE CANADA/ND/MN BORDER AND HAS SPARKED SHOWERS AND THUNDERSTORMS
ALONG THE SURFACE TROUGH WHERE THERE IS DEEPER MOISTURE. WITH THE
STORM MOTION TO THE SOUTHEAST AROUND 30-35KTS AND THE TROUGH SLOWLY
SAGGING SOUTHEAST...WOULD EXPECT THOSE SHOWERS TO MOVE SOUTHEAST
ACROSS WESTERN/CENTRAL UPPER MICHIGAN LATE THIS AFTERNOON AND INTO
THE EVENING HOURS. NOT ENTIRELY CONFIDENT ON THE EASTERN CWA...AS
IT WILL DEPEND ON THE THUNDERSTORMS CURRENTLY MOVING SOUTHEAST
FROM THUNDER BAY AND HOW FAR SOUTHEAST THEY WILL MAKE IT BEFORE
DIMINISHING. WILL HAVE LOWER POPS THAN OVER THE WEST...BUT STILL
IN THE LOW END CHANCE CATEGORY. AN EARLIER UPDATE COVERED THE
TIMING WELL OVER THE WEST AND HAVE JUST MADE MINOR TWEAKS TO
MATCH THE CURRENT CONDITIONS...WITH MOST AREAS IN THE HIGHER REACHES
OF THE SCATTERED/CHANCE CATEGORY. THINK THERE IS A DECENT SHOT MOST
LOCATIONS WILL SEE RAIN...BUT THE COVERAGE/TIMING WOULD BE BETTER
REFLECTED IN THE SCATTERED WORDING. AS MENTIONED ABOVE...THE DRY
AIR AND LIMITED INSTABILITY WILL BE THE MAIN LIMITING FACTORS TO
THE THUNDERSTORMS AND THEIR SEVERE POTENTIAL. BEST THREAT WILL BE
WEST-SOUTHWEST OF THE CWA WHERE THE 850-700/500MB LAPSE RATES ARE
THE STEEPEST...BUT THERE COULD BE SOME STRONGER STORMS OVER THE
SOUTHWEST THIRD OF THE CWA. HAIL POTENTIAL WILL BE LIMITED DUE TO
THE LIMITED INSTABILITY AND TALL/SKINNY CAPE. AS MENTIONED
ABOVE...GUSTY WINDS WILL BE THE BIGGEST THREAT OVER THE SW
HALF OF THE CWA...AS THEY HAVE THE STEEPER MID LEVEL LAPSE
RATES...COMBINED WITH THE DRY LOW LEVELS TO PRODUCE THE HIGHER
DCAPE VALUES.
THEN...AS THE SHORTWAVE TRACKS SOUTHEAST INTO NORTHWEST WISCONSIN
TONIGHT AND THE REST OF NORTHERN WISCONSIN ON MONDAY
MORNING...WOULD EXPECT SCATTERED SHOWERS TO CONTINUE THROUGH THE
NIGHT OVER THE SOUTHWEST HALF OF THE CWA. THAT IS ALSO WHERE
THE BEST 850-500MB Q-VECTOR CONV IS LOCATED EVEN THOUGH THE DEEPER
MOISTURE IS OVER EASTERN UPPER MICHIGAN. HAVE SLOWLY DIMINISHED THE
THUNDER THREAT OVERNIGHT AND INTO MONDAY MORNING TO BE OVER THE
SOUTHERN PART OF THE CWA...WHERE THE BETTER FORCING IS LOCATED. WILL
HOLD ON TO SOME LIGHT RAIN SHOWERS OVER NORTHERN UPPER MICHIGAN
OVERNIGHT TONIGHT AND INTO TOMORROW MORNING...AS LOW LEVEL
CONVERGENCE INCREASES WITH THE WINDS SHIFTING TO THE
NORTH-NORTHEAST. WITH DECENT MOISTURE BELOW 10KFT AS THAT
CONVERGENCE OCCURS...THINKING THERE WILL BE ENOUGH TO PRODUCE SOME
SHOWERS...ESPECIALLY OVER SOME OF THE HIGHER TERRAIN LOCATIONS OF
NORTH CENTRAL UPPER MICHIGAN WHERE THE WINDS BECOME UPSLOPE FOR A
PERIOD OF TIME.
THE LARGER SCALE FORCING SHOULD DEPART THE SOUTHWEST AND SOUTH
CENTRAL CWA AROUND DAYBREAK AND THEY WILL BE LEFT WITH ANY SHOWERS
DROPPING SOUTH ALONG THE ENHANCED CONVERGENCE. BEHIND THE
TROUGH...LOW CLOUDS SEEN IN CENTRAL ONTARIO/MANITOBA THIS MORNING
WILL MOVE SOUTH ACROSS THE CWA LATE TONIGHT INTO TOMORROW MORNING.
MODELS STRUGGLING WITH HOW LOW THE CLOUDS WILL BE...BUT EITHER WAY
A CLOUDY START TO THE WORK WEEK IS EXPECTED. CANADIAN HIGH PRESSURE
IS EXPECTED TO BUILD OVER THE AREA ON MONDAY AFTERNOON...BRINGING
DRIER AIR AND SUBSIDENCE TO THE AREA IN THE AFTERNOON. THIS WILL
PRODUCE DECREASING CLOUDS FROM NORTH TO SOUTH. HIGHS WILL BE MUCH
COOLER TOMORROW...WITH 60S IN MOST LOCATIONS EXCEPT NEAR LAKE
SUPERIOR WHERE NORTHERLY FLOW OFF THE LAKE WILL KEEP HIGHS IN THE
UPPER 50S.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 411 PM EDT SUN JUN 16 2013
THROUGH THE MIDDLE OF THE WEEK...NW FLOW WILL PREVAIL INTO THE UPPER
GREAT LAKES BTWN A RIDGE DRIFTING FROM THE ROCKIES TO THE PLAINS AND
A BROAD TROF OVER ERN NAMERICA. AS THE RIDGE SHIFTS TO THE
MISSISSIPPI VALLEY/GREAT LAKES LATE WEEK...IT WILL LOOSE AMPLITUDE
AS SHORTWAVE ENERGY EJECTING E FROM A TROF OVER THE NW CONUS BEGINS
TO SUPPRESS THE RIDGE. THE NW FLOW EARLY ON WILL SUPPORT DRY WEATHER
FOR UPPER MI. MOVING INTO THE LATE WEEK PERIOD...PATTERN SHOULD
BECOME ACTIVE WITH DECENT PCPN PROSPECTS AS SHORTWAVES TRACK E
ACROSS THE NRN PLAINS TO THE GREAT LAKES. AS FOR TEMPS...COOLEST
WEATHER WILL OCCUR OVER THE NEXT DAY OR TWO BEHIND SHORTWAVE PASSING
TONIGHT/MON. THEN...DESPITE NW FLOW...TEMPS THRU THE MIDWEEK PERIOD
SHOULD BE CLOSE TO NORMAL OR EVEN A LITTLE ABOVE NORMAL SINCE ERN
TROF WILL NOT HAVE SIGNIFICANT AMPLITUDE INTO THE ERN CONUS...
RESULTING IN COOLER AIR STAYING E AND NE OF THE AREA. TEMPS LATE
WEEK INTO THE WEEKEND WILL BE ABOVE NORMAL WITH WARMER/MORE HUMID
CONDITIONS. COULD BE UNCOMFORTABLY HUMID FOR A DAY OR TWO.
BEGINNING MON NIGHT...A CHILLY NIGHT IS ON THE WAY AS HIGH PRES
BUILDS INTO THE UPPER LAKES. WITH VERY DRY COLUMN (PRECIPITABLE
WATER 30-50PCT OF NORMAL) AND WINDS DIMINISHING TO LIGHT/CALM...WILL
CONTINUE TO FAVOR THE LOW END OF MODEL GUIDANCE FOR MIN TEMPS...
ESPECIALLY OVER THE W WHERE SFC HIGH PRES CENTER WILL BE ARRIVING
DURING THE NIGHT. WITH IDEAL RADIATIONAL COOLING CONDITIONS...THERE
IS A GOOD POTENTIAL FOR SOME FROST IN THE USUAL COLDER AREAS.
SOME OF THE TRADITIONAL COLD SPOTS COULD FALL TO NEAR FREEZING.
RECORD LOW FOR NWS MQT SITE ON THE 18TH IS 38F. NOT OUT OF THE
QUESTION THAT RECORD COULD BE TIED OR BROKEN.
SFC HIGH PRES WILL BE SETTLED OVER THE UPPER LAKES TUE...PROVIDING A
DRY/PLEASANT MID JUNE DAY WITH ABUNDANT SUNSHINE UNDER LINGERING
VERY DRY COLUMN. LAKE BREEZES WILL BE THE RULE...KEEPING LAKESIDE
LOCATIONS COOLER IN THE AFTN. GIVEN AVBL DRY AIR TO MIX DOWN...DWPTS
SHOULD FALL TO THE MID 30S...POSSIBLY LOWER...IN THE INTERIOR...
RESULTING IN MIN RH DOWN AROUND 25PCT. WOULDN`T BE SURPRISED TO SEE
SOME LOCATIONS FALL TO AROUND 20PCT. FORTUNATELY...LIGHT WINDS WILL
KEEP FIRE WX CONCERNS IN CHECK.
MEDIUM RANGE GUIDANCE HAS AND STILL CONTINUES TO HINT THAT A
SHORTWAVE WILL DROP SE...PASSING JUST N OF UPPER MI LATE WED/WED
NIGHT. GIVEN THE FAIRLY CONSISTENT SIGNAL FROM ALL MEDIUM RANGE
GUIDANCE...IT STILL APPEARS THERE MAY BE SOME PCPN AT SOME POINT
LATE WED/WED NIGHT. NOTHING MORE THAN SCHC/LOW CHC POPS ARE
WARRANTED SINCE BETTER FORCING PASSES BY TO THE N AND SINCE COVERAGE
WILL BE LOW IF PCPN DOES OCCUR. IF WAVE IS FASTER AND ARRIVES DURING
PEAK HEATING WED...PCPN CHC WILL BE GREATER...BUT WOULD STILL NOT
EXPECT ANYTHING MORE THAN SCT COVERAGE.
ON THU...THERE IS THE POTENTIAL FOR SUBTLE BOUNDARY ASSOCIATED WITH
THE SHORTWAVE PASSING BY THE AREA WED NIGHT TO HANG UP OVER/NEAR
UPPER MI...AND THAT COULD BE THE FOCUS FOR SOME CONVECTION THU AFTN.
MAINTAINED SCHC/LOW CHC POPS IN FCST.
AS MENTIONED EARLIER...THE LATE WEEK PERIOD INTO THE WEEKEND COULD
BECOME ACTIVE AS SHORTWAVES TRACK ACROSS THE NRN CONUS TO THE GREAT
LAKES...SUPPRESSING THE RIDGE THAT WAS SHIFTING ACROSS THE PLAINS
TOWARD THE AREA. SIGNAL LOOKS STRONG ENOUGH TO WARRANT AT LEAST MID
RANGE CHC POPS FOR SHRA/TSRA FOR PORTIONS OF FRI/SAT. SFC HIGH PRES
MAY BEGIN TO BUILD S TOWARD THE UPPER LAKES SUN IN THE WAKE OF A
SHORTWAVE SWINGING ACROSS HUDSON BAY/QUEBEC...SO PCPN CHANCES MAY
DIMINISH ON SUN. OVERALL...THERE APPEARS TO BE DECENT POTENTIAL THAT
MOST LOCATIONS WILL SEE SOME RAIN AT SOME POINT BTWN FRI AND SUN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 136 PM EDT SUN JUN 16 2013
AN UPPER LEVEL DISTURBANCE WILL COMBINE WITH A SURFACE TROUGH
DROPPING SOUTH ACROSS LAKE SUPERIOR TO PRODUCE SHOWERS AND SOME
THUNDERSTORMS FOR ALL TAF SITES THIS AFTERNOON INTO TONIGHT. DRY AIR
CURRENTLY OVER UPPER MICHIGAN HAS BEEN KEEPING THE DIURNAL CU IN
CHECK SO FAR THIS AFTERNOON. BUT AS THE DISTURBANCE NEARS OVER THE
NEXT FEW HOURS...THE POTENTIAL FOR SHOWERS WILL BE ON THE INCREASE.
THEY SHOULD AFFECT KCMX/KIWD FIRST AS THEY QUICKLY SLIDE SOUTHEAST
FROM THE MN ARROWHEAD. WILL HOLD OFF ON THUNDER MENTION FOR ALL BUT
KIWD DUE TO UNCERTAINTY IN TIMING/LOCATION OF THE SHOWERS. FELT
CONFIDENT ENOUGH WITH A LINE OF SHOWERS/THUNDERSTORMS NEARING DULUTH
TO MENTION THUNDER AT KIWD...BUT LEFT OUT OTHERWISE. THE SCATTERED
SHOWERS/THUNDERSTORMS WILL SPREAD SOUTHEAST THROUGH THE REST OF THE
EVENING...AS THE FRONT AND SHORTWAVE PASS THROUGH THE AREA.
OVERNIGHT...EXPECT THE THUNDER THREAT TO DIMINISH AND SLIDE
SOUTH. MEANWHILE...LIGHT NORTHERLY FLOW BEHIND THE SFC TROUGH WILL
TRY TO PULL LOW CLOUDS INTO THE AREA. THESE CLOUDS HAVE BEEN SEEN
OVER SOUTHERN ONTARIO TODAY...BUT THE MODELS HAVE BEEN VARYING ON
IF THEY WILL OCCUR LATE TONIGHT INTO TOMORROW MORNING. TO
COMPLICATE MATTERS...SOME FOG LINGERS OVER EASTERN LAKE
SUPERIOR...WHICH COULD SHIFT TOWARDS KSAW/KCMX WITH THE WINDS SHIFT
AND ADDITIONAL MOISTENING FROM THE SHOWERS. SINCE IT IS LATER IN
THE PERIOD...OPTED TO PLAY THE MIDDLE GROUND AT THIS POINT /MVFR
CEILINGS/ BUT IFR OR LOWER CEILINGS/VISIBILITY IS POSSIBLE AT
KCMX/KSAW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 411 PM EDT SUN JUN 16 2013
WINDS ARE EXPECTED TO STAY BELOW 20KTS THROUGH THE PERIOD. A TROUGH
WILL DROP SOUTH ACROSS LAKE SUPERIOR THIS EVENING...LEADING TO WINDS
SHIFTING TO THE NORTH TONIGHT. AS THE TROUGH CONTINUES SOUTHEAST ON
MONDAY...HIGH PRESSURE WILL BUILD OVER THE UPPER GREAT LAKES AND
REMAIN THROUGH WEDNESDAY. A WEAK TROUGH WILL THEN APPROACH THE AREA
FROM THE NORTHWEST FOR THURSDAY. THERE IS A POCKET OF FOG OVER
EASTERN LAKE SUPERIOR /NEAR AND EAST OF GRAND MARAIS MI/ THAT HAS
BEEN DIMINISHING AND MOVING AROUND TODAY. WOULD EXPECT THE DRY AIR
TO CONTINUE TO EAT AWAY AT IT THIS EVENING...BUT THERE IS SOME
CONCERN IT COULD EXPAND WITH RAIN OCCURRING OVER CENTRAL LAKE
SUPERIOR THIS AFTERNOON/EVENING AND LINGER THROUGH THE NIGHT. IF FOG
DOES LINGER TONIGHT...IT WILL CLEAR OUT MON MORNING AS MUCH DRIER AIR
SURGES S INTO THE UPPER LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...ROLFSON
AVIATION...SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
349 PM EDT SUN JUN 16 2013
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 349 PM EDT SUN JUN 16 2013
THE MAIN CONCERN FOR THE SHORT TERM FORECAST WILL BE THE ONGOING
SHOWERS AND THUNDERSTORMS AND ADDITIONAL SHOWERS WITH THE TROUGH
DROPPING SOUTH ACROSS THE AREA TONIGHT. INITIAL CONVECTION WAS OVER
EASTERN UPPER MICHIGAN...WHERE THERE WAS INCREASED MOISTURE FROM THE
FOG EARLIER TODAY AND CONVERGENCE FROM WEAK LAKE BREEZES. THESE
INITIAL SHOWERS HAVE SHIFTED TO THE SOUTHEAST AND OUT OF THE
CWA...BUT ARE SEEING SOME SHOWERS IN CENTRAL UPPER MICHIGAN ALONG
THE LAKE SUPERIOR LAKE BREEZE. THESE SHOWERS HAVE BEEN LIMITED THUS
FAR DUE TO THE DRY MID LEVEL AIR EVEN THOUGH THERE IS STRONG
LOW LEVEL LAPSE RATES AND RAP ANALYZED SB CAPE VALUES OF
500-1000 J/KG. BUT WITH THE INVERTED V LOOK TO THE RAP
SOUNDINGS...ML CAPES ARE STRUGGLING TO GET MUCH ABOVE 250-500 J/KG.
THIS DRY AIR CAN ALSO BE SEEN IN THE DEWPOINTS /UPPER 40S/ AWAY
FROM THE INFLUENCE OF THE GREAT LAKES. THERE HAVE EVEN BEEN SOME
SIGNIFICANT JUMPS IN THE DEWPOINTS OVER THE EASTERN CWA...AS THE
LAKE BREEZES HAVE MOVED IN AND OUT OF SOME OF THE SITES. FARTHER
WEST...A PERSISTENT SHOWER/THUNDERSTORM CLUSTER MOVED INTO WESTERN
GOGEBIC COUNTY OVER THE LAST HOUR AND DID PRODUCE SOME GUSTS UP TO
40KTS EVEN THOUGH THE CLUSTER IS DIMINISHING. THIS ISN/T TOO
UNREASONABLE WITH CURRENT DCAPE VALUES OVER MUCH OF UPPER MICHIGAN
AROUND 800-1000 J/KG AND THE INVERTED V SOUNDINGS. WOULD EXPECT
THIS TO BE THE PRIMARY CONCERN FOR ANY SHOWERS/THUNDERSTORMS LATE
THIS AFTERNOON AND EVENING. FINALLY...ADDITIONAL
SHOWERS/THUNDERSTORMS HAVE BEEN ONGOING JUST NORTHEAST OF LAKE
SUPERIOR...DUE TO ONE PIECE OF SHEARED OFF UPPER LEVEL ENERGY
DROPPING SOUTHEAST ALONG THE TROUGH. THESE SHOWERS WILL CONTINUE
QUICKLY SOUTHEAST AS THE STORM MOTION IS AROUND 40KTS.
THE AREA THAT WILL BRING THE BEST CHANCE FOR SHOWERS IS THE
REMNANT SHORTWAVE FROM THE UPPER LOW THAT WAS IN CENTRAL
SASKATCHEWAN YESTERDAY. THIS SHORTWAVE HAS STARTED TO MOVE TOWARDS
THE CANADA/ND/MN BORDER AND HAS SPARKED SHOWERS AND THUNDERSTORMS
ALONG THE SURFACE TROUGH WHERE THERE IS DEEPER MOISTURE. WITH THE
STORM MOTION TO THE SOUTHEAST AROUND 30-35KTS AND THE TROUGH SLOWLY
SAGGING SOUTHEAST...WOULD EXPECT THOSE SHOWERS TO MOVE SOUTHEAST
ACROSS WESTERN/CENTRAL UPPER MICHIGAN LATE THIS AFTERNOON AND INTO
THE EVENING HOURS. NOT ENTIRELY CONFIDENT ON THE EASTERN CWA...AS
IT WILL DEPEND ON THE THUNDERSTORMS CURRENTLY MOVING SOUTHEAST
FROM THUNDER BAY AND HOW FAR SOUTHEAST THEY WILL MAKE IT BEFORE
DIMINISHING. WILL HAVE LOWER POPS THAN OVER THE WEST...BUT STILL
IN THE LOW END CHANCE CATEGORY. AN EARLIER UPDATE COVERED THE
TIMING WELL OVER THE WEST AND HAVE JUST MADE MINOR TWEAKS TO
MATCH THE CURRENT CONDITIONS...WITH MOST AREAS IN THE HIGHER REACHES
OF THE SCATTERED/CHANCE CATEGORY. THINK THERE IS A DECENT SHOT MOST
LOCATIONS WILL SEE RAIN...BUT THE COVERAGE/TIMING WOULD BE BETTER
REFLECTED IN THE SCATTERED WORDING. AS MENTIONED ABOVE...THE DRY
AIR AND LIMITED INSTABILITY WILL BE THE MAIN LIMITING FACTORS TO
THE THUNDERSTORMS AND THEIR SEVERE POTENTIAL. BEST THREAT WILL BE
WEST-SOUTHWEST OF THE CWA WHERE THE 850-700/500MB LAPSE RATES ARE
THE STEEPEST...BUT THERE COULD BE SOME STRONGER STORMS OVER THE
SOUTHWEST THIRD OF THE CWA. HAIL POTENTIAL WILL BE LIMITED DUE TO
THE LIMITED INSTABILITY AND TALL/SKINNY CAPE. AS MENTIONED
ABOVE...GUSTY WINDS WILL BE THE BIGGEST THREAT OVER THE SW
HALF OF THE CWA...AS THEY HAVE THE STEEPER MID LEVEL LAPSE
RATES...COMBINED WITH THE DRY LOW LEVELS TO PRODUCE THE HIGHER
DCAPE VALUES.
THEN...AS THE SHORTWAVE TRACKS SOUTHEAST INTO NORTHWEST WISCONSIN
TONIGHT AND THE REST OF NORTHERN WISCONSIN ON MONDAY
MORNING...WOULD EXPECT SCATTERED SHOWERS TO CONTINUE THROUGH THE
NIGHT OVER THE SOUTHWEST HALF OF THE CWA. THAT IS ALSO WHERE
THE BEST 850-500MB Q-VECTOR CONV IS LOCATED EVEN THOUGH THE DEEPER
MOISTURE IS OVER EASTERN UPPER MICHIGAN. HAVE SLOWLY DIMINISHED THE
THUNDER THREAT OVERNIGHT AND INTO MONDAY MORNING TO BE OVER THE
SOUTHERN PART OF THE CWA...WHERE THE BETTER FORCING IS LOCATED. WILL
HOLD ON TO SOME LIGHT RAIN SHOWERS OVER NORTHERN UPPER MICHIGAN
OVERNIGHT TONIGHT AND INTO TOMORROW MORNING...AS LOW LEVEL
CONVERGENCE INCREASES WITH THE WINDS SHIFTING TO THE
NORTH-NORTHEAST. WITH DECENT MOISTURE BELOW 10KFT AS THAT
CONVERGENCE OCCURS...THINKING THERE WILL BE ENOUGH TO PRODUCE SOME
SHOWERS...ESPECIALLY OVER SOME OF THE HIGHER TERRAIN LOCATIONS OF
NORTH CENTRAL UPPER MICHIGAN WHERE THE WINDS BECOME UPSLOPE FOR A
PERIOD OF TIME.
THE LARGER SCALE FORCING SHOULD DEPART THE SOUTHWEST AND SOUTH
CENTRAL CWA AROUND DAYBREAK AND THEY WILL BE LEFT WITH ANY SHOWERS
DROPPING SOUTH ALONG THE ENHANCED CONVERGENCE. BEHIND THE
TROUGH...LOW CLOUDS SEEN IN CENTRAL ONTARIO/MANITOBA THIS MORNING
WILL MOVE SOUTH ACROSS THE CWA LATE TONIGHT INTO TOMORROW MORNING.
MODELS STRUGGLING WITH HOW LOW THE CLOUDS WILL BE...BUT EITHER WAY
A CLOUDY START TO THE WORK WEEK IS EXPECTED. CANADIAN HIGH PRESSURE
IS EXPECTED TO BUILD OVER THE AREA ON MONDAY AFTERNOON...BRINGING
DRIER AIR AND SUBSIDENCE TO THE AREA IN THE AFTERNOON. THIS WILL
PRODUCE DECREASING CLOUDS FROM NORTH TO SOUTH. HIGHS WILL BE MUCH
COOLER TOMORROW...WITH 60S IN MOST LOCATIONS EXCEPT NEAR LAKE
SUPERIOR WHERE NORTHERLY FLOW OFF THE LAKE WILL KEEP HIGHS IN THE
UPPER 50S.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 529 AM EDT SUN JUN 16 2013
THE WEATHER IN THE LONG TERM WILL NOT CHANGE DRAMATICALLY...WITH NO
SIGNIFICANT PATTERN CHANGES IN SIGHT. EXPECT 500MB LOW PRESSURE TO
REMAIN OVER NE CANADA AND HUDSON BAY THROUGH THE ENTIRE PERIOD.
WILL START OUT MONDAY WITH A GOOD AMOUNT OF CLOUD COVER...THANKS TO
COOL N FLOW OFF LAKE SUPERIOR /850MB TEMPS NEAR 7C ALONG THE SHORE/
AND THE 500MB SHORTWAVE BREAKING UP THE WEAK NW TO ZONAL FLOW. THE
SHORTWAVE WILL SLIDE IN FROM NE MN AND ONTARIO EARLY...WITH
IMPROVING CONDITIONS BY EARLY AFTERNOON. THE 500MB LOW SPINNING NEAR
JAMES BAY ON MONDAY WILL SWING ANOTHER WAVE DOWN FROM ONTARIO MONDAY
NIGHT...WITH VERY LITTLE IMPACT AS HIGH PRESSURE DOMINATES AT THE
SFC. FEW CLOUDS...LIGHT WINDS...AND COOL TEMPS FALLING INTO THE LOW
TO MID 30S SHOULD BE ENOUGH FOR PATCHY FROST ACROSS THE INTERIOR W
HALF OF UPPER MI AFTER MIDNIGHT MONDAY NIGHT INTO EARLY TUESDAY
MORNING.
DRY WEATHER SHOULD THEN BE THE RULE THROUGH AT LEAST WEDNESDAY...AS
THE SFC HIGH SLOWLY SINKS ACROSS LOWER MI. EXPECT A SLOW AND STEADY
WARMUP EACH DAY...WITH LAKE BREEZES LIKELY EACH AFTERNOON...COOLING
DOWN NEAR SHORE AREAS. WAA WILL INTENSIFY WEDNESDAY...WITH 850MB
TEMPS RISING TO AROUND 10C BY THE END OF THE DAY.
THERE COULD BE A SMALL CHANCE OF SHOWERS WEDNESDAY NIGHT INTO EARLY
THURSDAY MORNING...OR MORE THAN LIKELY JUST INCREASED CLOUD
COVER...ASSOCIATED WITH YET ANOTHER WAVE SWEEPING ACROSS THE UPPER
GREAT LAKES ON OUR QUICK NW FLOW ALOFT.
ALTHOUGH IT LOOKS LIKE A PRETTY WET PERIOD POP WISE FOR WEDNESDAY
NIGHT THROUGH SUNDAY...IT WILL BE A LOW CONFIDENCE FORECAST BEYOND
THIS PERIOD. THE CONSENSUS IS TO CONTINUE TO KEEP THE FAR EASTERN
AREAS A BIT DRIER...WITH A SFC LOW ORGANIZING ACROSS THE PLAINS
STATES FOR THE END OF THE WORK WEEK. THE BEST DYNAMICS LOOK TO STAY
TO OUR SOUTH...AS THE SFC LOW SLIDES TOWARD LAKE MI AND LOWER MI
SATURDAY NIGHT. IF THAT OCCURS...IT WILL GIVE THE EAST END OF UPPER
MI A GOOD CHANCE OF RECEIVING A WETTING RAIN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 136 PM EDT SUN JUN 16 2013
AN UPPER LEVEL DISTURBANCE WILL COMBINE WITH A SURFACE TROUGH
DROPPING SOUTH ACROSS LAKE SUPERIOR TO PRODUCE SHOWERS AND SOME
THUNDERSTORMS FOR ALL TAF SITES THIS AFTERNOON INTO TONIGHT. DRY AIR
CURRENTLY OVER UPPER MICHIGAN HAS BEEN KEEPING THE DIURNAL CU IN
CHECK SO FAR THIS AFTERNOON. BUT AS THE DISTURBANCE NEARS OVER THE
NEXT FEW HOURS...THE POTENTIAL FOR SHOWERS WILL BE ON THE INCREASE.
THEY SHOULD AFFECT KCMX/KIWD FIRST AS THEY QUICKLY SLIDE SOUTHEAST
FROM THE MN ARROWHEAD. WILL HOLD OFF ON THUNDER MENTION FOR ALL BUT
KIWD DUE TO UNCERTAINTY IN TIMING/LOCATION OF THE SHOWERS. FELT
CONFIDENT ENOUGH WITH A LINE OF SHOWERS/THUNDERSTORMS NEARING DULUTH
TO MENTION THUNDER AT KIWD...BUT LEFT OUT OTHERWISE. THE SCATTERED
SHOWERS/THUNDERSTORMS WILL SPREAD SOUTHEAST THROUGH THE REST OF THE
EVENING...AS THE FRONT AND SHORTWAVE PASS THROUGH THE AREA.
OVERNIGHT...EXPECT THE THUNDER THREAT TO DIMINISH AND SLIDE
SOUTH. MEANWHILE...LIGHT NORTHERLY FLOW BEHIND THE SFC TROUGH WILL
TRY TO PULL LOW CLOUDS INTO THE AREA. THESE CLOUDS HAVE BEEN SEEN
OVER SOUTHERN ONTARIO TODAY...BUT THE MODELS HAVE BEEN VARYING ON
IF THEY WILL OCCUR LATE TONIGHT INTO TOMORROW MORNING. TO
COMPLICATE MATTERS...SOME FOG LINGERS OVER EASTERN LAKE
SUPERIOR...WHICH COULD SHIFT TOWARDS KSAW/KCMX WITH THE WINDS SHIFT
AND ADDITIONAL MOISTENING FROM THE SHOWERS. SINCE IT IS LATER IN
THE PERIOD...OPTED TO PLAY THE MIDDLE GROUND AT THIS POINT /MVFR
CEILINGS/ BUT IFR OR LOWER CEILINGS/VISIBILITY IS POSSIBLE AT
KCMX/KSAW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 349 PM EDT SUN JUN 16 2013
WINDS ARE EXPECTED TO STAY BELOW 20KTS THROUGH THE PERIOD. A TROUGH
WILL DROP SOUTH ACROSS LAKE SUPERIOR THIS EVENING...LEADING TO WINDS
SHIFTING TO THE NORTH TONIGHT. AS THE TROUGH CONTINUES SOUTHEAST ON
MONDAY...HIGH PRESSURE WILL BUILD OVER THE UPPER GREAT LAKES AND
REMAIN THROUGH WEDNESDAY. A WEAK TROUGH WILL THEN APPROACH THE AREA
FROM THE NORTHWEST FOR THURSDAY. THERE IS A POCKET OF FOG OVER
EASTERN LAKE SUPERIOR /NEAR AND EAST OF GRAND MARAIS MI/ THAT HAS
BEEN DIMINISHING AND MOVING AROUND TODAY. WOULD EXPECT THE DRY AIR
TO CONTINUE TO EAT AWAY AT IT THIS EVENING...BUT THERE IS SOME
CONCERN IT COULD EXPAND WITH RAIN OCCURRING OVER CENTRAL LAKE
SUPERIOR THIS AFTERNOON/EVENING AND LINGER THROUGH THE NIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...KF
AVIATION...SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
210 PM EDT SUN JUN 16 2013
.SYNOPSIS...
HIGH PRESSURE WILL MOVE OFFSHORE THIS EVENING...AHEAD OF AN UPPER
LEVEL DISTURBANCE THAT MOVES THROUGH THE REGION OVERNIGHT AND
MONDAY. A COLD FRONT SLOWLY APPROACHES FROM THE NORTHWEST LATE
MONDAY AND MOVES ACROSS THE REGION LATE TUESDAY INTO WEDNESDAY
MORNING.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1150 AM SUNDAY...
THE UPPER RIDGE WILL CONTINUE TO FLATTEN TODAY AS SURFACE HIGH
PRESSURE CONTINUES TO MOVE OFF TO THE SOUTHEAST...AND THE GRADIENT
TIGHTENS BETWEEN THE RETREATING HIGH AND SURFACE TROUGHINESS
SHARPENING OVER THE WESTERN PART OF THE STATE. THE 12Z KGSO
SOUNDING...AS WELL AS THE SOUNDING FROM KMHX...SHOWED A DECENT CAP
REMAINING AROUND 700MB...WHILE THE KRNK SOUNDING INDICATED JUST
SLIGHTLY COOLER TEMPERATURES JUST ABOVE 700MB ALBEIT WITH A WEAK CAP
IN PLACE. THE RAP SOUNDINGS FORECAST THIS CAP ESSENTIALLY REMAINING
FOR THE REST OF THE DAY...VERY GRADUALLY DIMINISHING ESPECIALLY
TOWARD THE NORTHWEST PIEDMONT AS THE RIDGE FLATTENS...UPPER LEVELS
COOL...AND THE OVERALL MOISTURE OF THE AIR MASS INCREASES. THE RAP
FORECASTS 850MB SUBSIDENCE THROUGHOUT THE DAY...WITH ANY MODEST UVV
WITH APPROACHING MID-LEVEL SHORTWAVES HOLDING OFF UNTIL 00Z AND
AFTER. THE LATEST HRRR WRF IS DRY AS WELL...ALONG WITH QPF FROM THE
RAP. WILL CONTINUE WITH A DRY FORECAST TODAY...AND EXPECT PERIODS OF
MOSTLY MID- AND SOME HIGH-LEVEL CLOUDS TO RESULT IN A
PARTLY-TO-MOSTLY SUNNY LATE MORNING AND AFTERNOON. ALREADY THERE
HAVE BEEN A FEW WIND GUSTS IN THE TEENS KNOTS AND...BASED ON THE
LATEST RAP SOUNDINGS AND THE WINDS ALOFT ON THE KRAX 88D VAD WIND
PROFILE...INCREASED THE GUSTS A TRIFLE ESPECIALLY OUTSIDE OF
SOUTHEAST AREAS TO MORE AROUND 20KT. WHILE THE MAV MOS HAS SIMPLY
BEEN TOO WARM OF LATE...THE MET MOS IS CLOSER TODAY TO THE MAV AND
TO THE ONGOING FORECAST. LOWERED A DEGREE TOWARD KRWI BASED ON THE
LATEST TRENDS AND MOS...AND AS A RESULT OF SLIGHTLY COOLER
1000-850MB THICKNESSES COMPARED TO THE REST OF CENTRAL NORTH
CAROLINA. STILL...HIGHS 85 TO 90.
THE VERY LATEST GUIDANCE HAS BEEN A LITTLE MORE AGGRESSIVE WITH THE
POTENTIAL FOR AT LEAST LIGHT QPF MOVING IN A LITTLE MORE IN EARNEST
INTO NORTHERN AREAS OVERNIGHT...MAINLY AFTER 02Z OR SO. MID-LEVEL
COOLING AND OVERALL MOISTENING ON THE NAM IS EFFICIENT OVERNIGHT...
AND THE LATEST HRRR WRF SUGGESTS UPSTREAM PRECIPITATION CURRENTLY
OVER SOUTHERN ILLINOIS INTO KENTUCKY ABLE TO MAKE STEADY PROGRESS
EAST-SOUTHEAST INTO AT LEAST THE TRIAD AND TOWARD KTDF AS
MOISTENING...AND COOLING ALOFT...OCCUR. FOR THE LATE MORNING
UPDATE...RAISED POPS INTO CHANCE FOR THAT AREA. WILL NOTE THE LATEST
NAM MOS GUIDANCE IS INTO CATEGORICAL IN THE TRIAD FOR THE OVERNIGHT
HOURS...DIMINISHING BUT STILL HIGHER ELSEWHERE. AFTER A REVIEW OF
THE GFS...MAY NEED TO SHOW SOME FURTHER INCREASE FOR MANY PARTS OF
CENTRAL NORTH CAROLINA OVERNIGHT. OTHERWISE...CLOUDINESS...AGAIN
MAINLY MID AND UPPER...WILL BECOME PREVALENT TONIGHT AS THE
APPROACHING FRONT TRANSLATES INTO THE LEE TROUGH. MINS WILL BE MILD
AND SEASONABLE...UPPER 60S.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 315 AM SUNDAY...
MONDAY AND MONDAY NIGHT...TRANSITION TO A BROAD LONGWAVE TROF WILL
BE UNDERWAY AND THE LINGERING LOW LEVEL TROFFING ALONG THE ATLANTIC
SEABOARD WILL PROMOTE AN INCREASINGLY MOIST AIRMASS. THICKNESSES ARE
RELATIVELY HIGH AND SIMILAR TO SUNDAY...WITH THE POTENTIAL FOR UPPER
80S. MOSTLY CLOUDY SKIES WILL HAMPER INSOLATION A BIT...MOSTLY MID
80S WEST TO UPPER 80S EAST. CHANCES OF SHOWERS WILL INCREASE MONDAY
AFTERNOON INTO MONDAY NIGHT IN INCREASINGLY DISTURBED FLOW...BUT ITS
DIFFICULT TO PICK OUT A PARTICULAR FEATURE DURING THIS TIME FRAME TO
FOCUS ACTIVITY...WILL CONTINUE CHANCE CATEGORY POPS FAVORING THE
WEST AND NORTH.
TUESDAY AND TUESDAY NIGHT: WITHIN A BROAD TROUGH ALOFT EAST OF THE
ROCKIES...A LOW AMPLITUDE SOUTHERN STREAM SHORTWAVE TROUGH...AND
PERHAPS A PRECEDING MCV FROM CONVECTION INITIATED AHEAD OF THIS WAVE
OVER THE CENTRAL PLAINS LATER TODAY AND TONIGHT...WILL MIGRATE
THROUGH THE BASE OF THE TROUGH/ACROSS THE CENTRAL APPALACHIANS AND
MIDDLE ATLANTIC REGION TUE. THESE FEATURES WILL BE FOLLOWED QUICKLY
BY AN ELONGATED BUT STRONGER NORTHERN STREAM WAVE IN NW FLOW FROM
THE UPPER MIDWEST TO THE CENTRAL APPALACHIANS TUE NIGHT.
IN THE LOW LEVELS...A PRE-FRONTAL TROUGH OVER VA/NC TUE WILL BE
OVERTAKEN BY A COLD FRONT ATTENDING THE AFOREMENTIONED NORTHERN
STREAM S/W TROUGH...AND THIS MERGED BOUNDARY WILL SETTLE SOUTHWARD
ACROSS CENTRAL NC TUE NIGHT. WITH A CONDITIONALLY UNSTABLE AND
UNCAPPED ENVIRONMENT PER BUFR SOUNDINGS...AND WITH FORECAST
PRECIPITABLE WATER VALUES APPROACHING TWO INCHES...THE WEAK (~20
METER/12 HR) HEIGHT FALLS ASSOCIATED WITH THE SERIES OF DISTURBANCES
ALOFT AND LOW LEVEL CONVERGENCE ALONG THE PRE-FRONTAL TROUGH/FRONT
WILL SUPPORT THE DEVELOPMENT OF NUMEROUS TO WIDESPREAD SHOWERS AND
STORMS TUE. THE SLOW SOUTHWARD PASSAGE OF THE SURFACE FRONT WILL END
THE THREAT OF CONVECTION FROM NORTH TO SOUTH TUE EVENING AND
OVERNIGHT...WITH JUST A LINGERING CHANCE OF A FEW SHOWERS ALONG THE
FAR SOUTHERN TIER BY WED MORNING.
WHILE WSW MEAN FLOW ALIGNED PARALLEL TO THE UNDERLYING SURFACE FRONT
SUGGESTS DOWNPOURS/ LOCALIZED FLOODING IN TRAINING STORMS ALONG THE
BOUNDARY MAY PROVIDE THE GREATEST IMPACT...INCREASING MID LEVEL
FLOW/BULK SHEAR TO AROUND 30 KTS MAY ALSO SUPPORT MULTI-CELL STORM
ORGANIZATION WITH PRECIPITATION-LOADED STRONG WET MICROBURST WIND
GUSTS. IN ADDITION...FORECAST MAXIMUM SRH AROUND 100 M2/S2 COULD BE
NEARLY DOUBLED LOCALLY INVOF OUTFLOW/BACKED SURFACE FLOW...WHICH
COULD SUPPORT BRIEF SUPERCELLULAR STRUCTURES...THOUGH SUCH A
SCENARIO WILL BE DEPENDENT ON MESO AND STORM SCALE INFLUENCES WITH
LIMITED PREDICTABILITY BEYOND A FEW HOURS. AS SUCH...WILL INCLUDE
ONLY A GENERIC ONE SENTENCE MENTION OF A STRONG TO SEVERE STORM IN
THE HWO FOR NOW FOR TUE. MOSTLY CLOUDY AND STORMY CONDITIONS WILL
SUPPORT HIGHS FROM THE UPPER 70S NW...TO LOWER TO MIDDLE 80S OVER
THE SOUTH...WITH LOWS MOSTLY IN THE UPPER 60S...TO AROUND 70 DEGREES
SOUTH.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 255 AM SUNDAY...
WEDNESDAY THROUGH SATURDAY: BELOW AVERAGE TEMPERATURES - IN THE
UPPER 70S TO LOWER-MIDDLE 80S - IN WEAK POST-FRONTAL HIGH PRESSURE
AND ASSOCIATED GENERALLY EAST TO ENE LOW LEVEL FLOW...WILL THEN
PREVAIL THROUGH THE END OF THE WEEK. HOWEVER...THE SURFACE FRONT
WILL LIKELY LINGER OVER SC THROUGH THU GIVEN CONTINUED FRONT-
PARALLEL FLOW ALOFT IN THE BASE OF BROAD EASTERN CONUS TROUGH. WILL
ACCORDINGLY MAINTAIN A SLIGHT CHANCE OF A SHOWER OR STORM OVER THE
FAR SOUTHERN SANDHILLS AND COASTAL PLAIN...IN CLOSEST PROXIMITY TO
THIS FRONT AND HIGHER BL MOISTURE...AND ALSO TOWARD THE YADKIN RIVER
WHERE A FEW WEAKENING SHOWERS/STORMS MAY DRIFT AFTER INITIATION AND
PROPAGATION FROM THE EASTERN SLOPES. A WARMER SOUTHEASTERLY...TO
SOUTHERLY RETURN FLOW BY SATURDAY...WILL RESULT IN RISING
TEMPERATURES TO AROUND THE 30-YEAR AVERAGE...AND HUMIDITY
LEVELS...BY THE WEEKEND. A RISK OF A FEW LATE AFTERNOON PULSE
SHOWERS OR STORMS WILL CONSEQUENTLY INCREASE TO NEAR CLIMATOLOGICAL
PROBABILITIES...AROUND 20 PERCENT OR SO...BY SAT.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
AS OF 210 PM SUNDAY...
SOMEWHAT CHALLENGING TAF FORECAST...DEPENDENT ON HOW MUCH
PRECIPITATION IS ABLE TO MAKE IT SOUTHEAST INTO THE SLIGHTLY MORE
CAPPED AIR MASS. OVERNIGHT...EXPECT A HIGH PROBABILITY OF VFR
CONDITIONS...WITH A CHANCE OF A PERIOD OF MVFR CONDITIONS IN
SCATTERED SHOWERS. THE CHANCES FOR AREAS OF MVFR CONDITIONS IMPROVE
LATE TONIGHT AND MONDAY...IN AT LEAST SCATTERED AREAS OF SHOWERS AND
WIDELY SCATTERED THUNDERSTORMS. SREF PROBABILITIES OF IFR CONDITIONS
ARE CURRENTLY LOW AND WILL SHOW CENTRAL NORTH CAROLINA TAF SITES
ONLY GETTING AS LOW AS MVFR DURING THE 18Z VALID TAF PERIOD.
MODESTLY GUSTY SOUTHWEST SURFACE WINDS THIS AFTERNOON WILL DIMINISH
TO MAINLY 5 TO 10KT OVERNIGHT...HOWEVER...DURING THE OVERNIGHT
PERIOD WINDS WITHIN 3K FEET OF THE SURFACE SHOULD INCREASE TO 25 TO
30KT...WITH WINDS AT THAT LEVEL DIMINISHING TOWARD 12Z MONDAY.
BEYOND THE 18Z VALID TAF PERIOD...GOOD PROBABILITY OF PERIODS OF
SUB-VFR CONDITIONS MONDAY AFTERNOON THROUGH TUESDAY IN LOW CLOUDS
AND SCATTERED-TO-NUMEROUS SHOWERS AND THUNDERSTORMS. CONDITIONS
BECOME PRIMARILY VFR WEDNESDAY THROUGH FRIDAY...OUTSIDE OF ANY
REMAINING ISOLATED SHOWERS AND THUNDERSTORMS.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...KMC/DJF
NEAR TERM...DJF/MLM
SHORT TERM...MLM/MWS
LONG TERM...MWS
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1258 PM CDT SUN JUN 16 2013
.UPDATE...
ISSUED AT 1247 PM CDT SUN JUN 16 2013
NO SURPRISES SO FAR FROM THE EVOLVING WEATHER. CUMULUS RAPIDLY
FORMING ALONG THE NORTHERN THIRD OF THE STATE WITH ASSOCIATED
SHOWERS SLOWLY DEVELOPING. MAY SEE AN ISOLATED THUNDERSTORMS BUT
NOT WIDESPREAD. DROPPED THE THUNDERSTORM MENTION TO ISOLATED.
RAISED THE HIGH TEMPERATURE A DEGREE OR TWO SOUTH CENTRAL. SO FAR
WINDS APPEAR TO REMAIN BELOW ADVISORY CRITERIA.
UPDATE ISSUED AT 1006 AM CDT SUN JUN 16 2013
UPPER LOW OVER SASKATCHEWAN OPENING UP AND MOVING SOUTHEAST AS
FORECAST. THIS WILL BRING CLOUDS INTO THE NORTH WITH SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS THIS AFTERNOON. MAIN CHANGES
THIS FORECAST ARE WINDS FOR THE JAMES RIVER VALLEY. UPPED WINDS TO
20 TO 35 MPH. STILL BELOW WIND ADVISORY CRITERIA BUT WILL WATCH.
UPDATE ISSUED AT 642 AM CDT SUN JUN 16 2013
CLEAR SKIES ACROSS WESTERN AND CENTRAL NORTH DAKOTA THIS MORNING
WITH CLOUDS ASSOCIATED WITH A LOW PRESSURE SYSTEM OVER SOUTHERN
SASKATCHEWAN STARTING TO INCH CLOSER TO THE NORTHERN TIER
COUNTIES. MINIMAL CHANGES TO THE GOING FORECAST THIS MORNING. DID
LOWER SKY COVER ACROSS THE NORTH THROUGH MID MORNING. ALSO DROPPED
THE MENTION OF THUNDER UNTIL AFTERNOON. LATEST 06Z GFS BUFR
SOUNDINGS FROM KISN AND KMOT INDICATE CONVECTION WILL BE HARD TO
DEVELOP BEFORE 18 UTC. WILL NEED TO MONITOR THE SOUTH FOR POSSIBLE
SHOWERS THIS AFTERNOON...BUT BETTER MOISTURE SHOULD REMAIN SOUTH
OF THE BORDER. LATEST 06 UTC NAM KEEPS ACTIVITY SOUTH OF THE
BORDER EXCEPT FOR MAYBE CLIPPING THE FAR SOUTHEAST CWA LATE THIS
AFTERNOON. THE 10Z RAP ALSO KEEPS ACTIVITY SOUTH OF THE BORDER.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 402 AM CDT SUN JUN 16 2013
MAIN FORECAST CONCERNS ARE WINDS TODAY AND PRECIP CHANCES/COVERAGE
THIS AFTERNOON AND EVENING.
WV IMAGERY CONTINUES TO SHOW UPPER LOW OVER CENTRAL SASKATCHEWAN
DRIFTING SOUTHWARD TOWARD NORTH DAKOTA. SATELLITE IMAGERY AND
SURFACE OBS SHOW EXTENSIVE AREA OF LOW CEILINGS IN CANADA
ASSOCIATED WITH THIS LOW. MOS GUIDANCE...MODEL RH FIELDS AND
FORECAST SOUNDINGS INDICATE SOME OF THESE LOW CEILINGS COULD
SPREAD INTO OUR CWA...MAINLY CENTRAL AND EASTERN PORTIONS LATE
SUNDAY NIGHT INTO MONDAY MORNING.
OTHERWISE...MODELS ARE IN DECENT AGREEMENT BRINGING SHOWER
ACTIVITY ACROSS CANADIAN BORDER BY AROUND 18Z AS UPPER LOW CLIPS
NORTHEASTERN ND. PRECIP AMOUNTS WITH ANY SHOWERS SHOULD BE ON THE
LIGHT SIDE AND CONVECTION SHOULD DIE OUT BY 06Z.
WITH REGARD TO WINDS TODAY...FORECAST SOUNDINGS/BUFKIT DATA LIMIT
WINDS IN THE MIXED LAYER AT MOST LOCATIONS TO 30 KTS...SO ANOTHER
BREEZY DAY EXPECTED BUT DO NOT SEE WIND ADVISORY CRITERIA BEING
MET.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 402 AM CDT SUN JUN 16 2013
NEAR NORMAL TEMPERATURES WILL HIGHLIGHT THE EXTENDED PERIOD WITH
A MORE ACTIVE PATTERN FOR THUNDERSTORMS POTENTIALLY BECOMING
ESTABLISHED WEDNESDAY NIGHT THROUGH SATURDAY.
THE 12 UTC GUIDANCE SUITE IS IN GOOD AGREEMENT THROUGH MOST OF THE
EXTENDED FORECAST PERIOD AND WILL USE A MODEL BLEND WITH PERSISTENCE
FOR MOST FIELDS. AN UPPER LEVEL RIDGE IS FORECAST TO MOVE INTO THE
CENTRAL U.S. MONDAY AND REMAIN THROUGH AT LEAST WEDNESDAY BEFORE
A SHIFT OF THE AXIS TO THE EAST WEDNESDAY NIGHT INTO NEXT
WEEKEND... WHICH WOULD YIELD SOUTHWEST FLOW ALOFT OVER THE
NORTHERN PLAINS. THIS UPPER LEVEL PATTERN SUPPORTS NEAR NORMAL
TEMPERATURES ACROSS WESTERN AND CENTRAL NORTH DAKOTA...WITH
THUNDERSTORM CHANCES INCREASING WEDNESDAY NIGHT THROUGH SATURDAY
WITH THE FORECAST TRANSITION TO A FAVORABLE SOUTHWEST FLOW ALOFT
WITH SEVERAL IMPULSES POTENTIALLY EJECTING OUT OF THE APPROACHING
UPPER LEVEL LOW. DIFFERENCES THAT DO CROP UP WITH THE PROGRESSION
OF THE UPPER LOW FROM THE NORTHERN ROCKIES INTO THE SOUTHERN
CANADIAN PRAIRIE PROVINCES LATE IN THE EXTENDED PERIOD WILL HAVE
LITTLE IMPACT ON THE RESULTING FORECAST THROUGH SATURDAY NIGHT AS
THE ACTIVE FLOW PATTERN WILL PERSIST EITHER WAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1247 PM CDT SUN JUN 16 2013
MAIN HAZARDS TO AVIATION INCLUDE MVFR CEILINGS...ISOLATED
THUNDERSTORMS AND GUSTY WINDS. AT NOON CDT...SURFACE LOW PRESSURE
CENTERED IN SOUTHWEST MANITOBA IS FORECAST TO MOVE SOUTHEAST TONIGHT.
THIS LOW WILL BE THE FOCUS FOR SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS ACROSS NORTHERN INTO CENTRAL NORTH DAKOTA SUNDAY
AFTERNOON AND EVENING. BECAUSE TSRA WILL BE ISOLATED...LEFT OUT OF
THE TAF AND JUST MENTIONED VCSH. CLOUDS FROM REGINA TO ESTEVAN
SASKATCHEWAN CURRENTLY SHOWING UP BELOW 2000 AGL...SO ADDED MVFR
CEILINGS TO KMOT BY THIS EVENING. MVFR CONDITIONS WILL DEVELOP
FROM KMOT-KJMS OVERNIGHT. OTHERWISE VFR FROM KISN- KDIK- KBIS.;
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...JNS
LONG TERM...TWH
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
127 PM EDT SUN JUN 16 2013
.SYNOPSIS...
LOW PRESSURE FROM THE UPPER MIDWEST WILL MOVE ACROSS THE GREAT
LAKES ON TODAY AND DRAG A WEAK COLD FRONT ACROSS THE REGION. A
STRONGER COLD FRONT FROM CANADA WILL DROP ACROSS THE LOWER GREAT
LAKES MONDAY NIGHT. HIGH PRESSURE FROM CANADA WILL BUILD SOUTH
ACROSS THE GREAT LAKES BY MID WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
JUST SOME SCATTERED SHOWERS AT THE MOMENT. EXPECT A GRADUAL
DECREASE IN THIS ACTIVITY THE REMAINDER OF THE MORNING. MODELS
CONTINUE TO SUGGEST NEW DEVELOPMENT THIS AFTERNOON AS A WEAK
TROUGH SLIDES EAST ACROSS THE REGION. LATEST HRRR HAS MOST OF THIS
ACTIVITY OVER THE SE 1/2 OF THE AREA WHICH SEEMS REASONABLE. HAVE
ADJUSTED PRECIP CHANCES AS NEEDED. NO CHANGES TO TEMPS FOR NOW BUT
WILL TAKE ANOTHER LOOK IN A COUPLE OF HOURS. SUSPECT BY MID
AFTERNOON THAT MOST OF THE PRECIP WILL BE ALONG AND SOUTH OF THE
U.S. 30 CORRIDOR.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
THIS EVENING THE SLOW MOVING COLD FRONT WILL STILL BE ACROSS THE
AREA SO EARLY ON WILL NEED TO HOLD ONTO CHANCE POPS SE. AFTER
MIDNIGHT HOWEVER DROPPED THE MENTION OF PRECIP AS DRIER MORE
STABLE AIR MOVES IN. THIS WILL BE SHORT LIVED HOWEVER AS ANOTHER
LOW DROPS ACROSS THE CENTRAL GREAT LAKES ON MONDAY. MODELS BRING
THE COLD FRONT SOUTH ACROSS THE LAKES TO THE VICINITY BY 00Z
TUESDAY. MODELS ALSO BRING MORE MOISTURE INTO THE AREA DURING THE
DAY MONDAY. WILL BEGIN MONDAY DRY BUT WITH THE APPROACHING
SYSTEM...WILL HAVE CHANCE POPS NORTH AND SLIGHT CHANCE SOUTH FOR
THE AFTERNOON. MONDAY EVENING THE FRONT WILL DROP ACROSS THE AREA.
BY TUESDAY MORNING THE MODELS BEGIN TO DIVERGE WITH THE NAM
DEVELOPING A SURFACE LOW ACROSS NORTHERN OHIO AND DEEP MOISTURE
ACROSS THE REGION. THE GFS AND SREF ARE MORE SIMILAR BUILDING
DRIER AIR SOUTH ACROSS THE LAKES TO OUR NORTHERN BORDER WHILE
KEEPING ANY SURFACE LOW AND THE DEEP MOISTURE WELL SOUTH OF THE
AREA. WILL SIDE WITH THE SREF/GFS HERE. WILL HAVE CHANCE POPS
MONDAY NIGHT AND TUESDAY MORNING WITH THE FRONT...TAPERING FROM
THE NORTH/NORTHWEST TUESDAY AFTERNOON. HIGH PRESSURE BUILDS IN
TUESDAY NIGHT AND WEDNESDAY SO DRY AND A FEW DEGREES BELOW NORMAL
FOR MID WEEK.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
OVERALL CENTRAL U.S. RIDGE IS EXPECTED TO SHIFT EAST FROM THURSDAY
THROUGH SATURDAY WHILE FLATTENING TO SOME DEGREE. THERE ARE
SIGNIFICANT ENOUGH DIFFERENCES IN THE MODELS TO NOT MAKE ANY MAJOR
CHANGES TO THE CURRENT FORECAST. THE GFS IS STRONGER WITH THE RIDGE
AND THEREFORE WARMER AND DRIER. THE ECMWF ON THE OTHER HAND FLATTENS
THE RIDGE MORE AND ALLOWS SOME SHORTWAVE ENERGY TO TOP THE RIDGE AND
MOVE ACROSS THE GREAT LAKES. THIS WOULD BRING WITH IT SHRA/TS AND
LIKELY COOLER TEMPS DEPENDING ON CLOUD COVER. ALL IN ALL
TEMPERATURES WILL BE SEASONABLE...BUT MAY GET WARM IF WE TREND
TOWARD THE GFS WHICH IS RUNNING A COUPLE DEGREES WARMER AT H8. WHILE
THURSDAY WILL BE DRY...SLOWLY BRING UP PRECIP CHANCES AND CLOUD
COVER GOING INTO THE WEEKEND WITH THE INCREASED MOISTURE AND
POSSIBLE BOUNDARIES IN THE AREA.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
COLD FRONT JUST SOUTH OF THE ERIE LAKESHORE AND SHOULD PUSH SOUTH
OF THE AREA THIS EVENING. COULD SEE A FEW SHOWERS AND ISOLATED
TSRA THIS EVENING...MAINLY SOUTH OF A YNG TO FDY LINE. IN TAFS
JUST WENT VCSH. CIGS SHOULD GRADUALLY IMPROVE TO VFR EVERYWHERE. SHOULD
ALSO BE A PARTIAL CLEARING TONIGHT AS DRIER AIR SPREADS OVER THE
AREA. AS CLOUDS CLEAR MAY LEAD TO SOME FG/BR TO DEAL WITH MONDAY
MORNING.
.OUTLOOK...NON VFR POSSIBLE MONDAY NIGHT INTO TUESDAY WITH SHRA/TSRA.
&&
.MARINE...
LOW PRESSURE CROSSING NORTHERN LAKE MICHIGAN EARLY THIS MORNING IS
EXPECTED TO DEEPEN A LITTLE FURTHER AS IT SHIFTS EAST ACROSS ONTARIO
CANADA. IT WILL BRING SHOWERS/THUNDERSTORMS TO THE LAKE TODAY WITH
THE COLD FRONT CROSSING BY THIS AFTERNOON. THERE IS A LITTLE BIT OF
WIND WITH THIS SYSTEM. FEEL THERE IS ENOUGH TO GENERATE SOME 4 FOOT
WAVES ACROSS THE EAST END WITH THE WEST-SOUTHWEST FLOW. WILL HOLD
BACK ON A SMALL CRAFT ADV...BUT WILL MONITOR FOR
DEVELOPMENTS/CHANGES. NEXT FRONT ON THE HEELS OF TODAY/S AND WILL
CROSS THE LAKE 24-30 HOURS LATER...MONDAY LATE AFTERNOON. HIGH
PRESSURE WILL OVERSPREAD THE CENTRAL GREAT LAKES AND A
NORTH-NORTHEAST FLOW WILL BE REALIZED ON LAKE ERIE FOR TUESDAY INTO
WEDNESDAY. HIGH PRESSURE OVERHEAD WED-THU.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TK
NEAR TERM...KUBINA
SHORT TERM...TK
LONG TERM...OUDEMAN
AVIATION...DJB
MARINE...OUDEMAN
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
318 PM CDT SUN JUN 16 2013
.DISCUSSION...
WET PATTERN SETTING OVER THE MIDSOUTH OVER THE NEXT COUPLE OF
DAYS AS A COLD FRONT AND SEVERAL SHORTWAVES MOVE INTO THE REGION.
TONIGHT...VERY LOW CONFIDENCE ON WHAT WILL HAPPEN AS MODELS DID
NOT INITIALIZE VERY WELL. ABUNDANCE OF CLOUD COVER OVER THE REGION
HAS KEPT THE ATMOSPHERE MORE STABLE THAN WHAT THE MODELS WERE
INDICATING. THUS THE NAM AND RAP MODELS SHOWED NUMEROUS SHOWERS
AND THUNDERSTORMS DEVELOPING THIS AFTERNOON INTO THE EVENING HOURS
DUE TO THE COMBINATION OF PEAK HEATING AND THE EXPECTED UNSTABLE
ATMOSPHERE. THIS IS NOT THE CASE AT LEAST SO FAR. HOWEVER...WITHIN
THE LAST 45 MINUTES A THUNDERSTORM HAS DEVELOPED OVER PANOLA
COUNTY. THE NAM AND RAP SHOWED WHATEVER ACTIVITY DEVELOPED DYING
OUT AFTER SUNSET. MEANWHILE...OTHER MODELS LIKE THE HRRR SHOWED
DEVELOPMENT ALONG AND AHEAD OF AN OUTFLOW BOUNDARY WHICH IS DRAPED
ACROSS SOUTHERN MISSOURI. BEGINNING TO SEE DEVELOPMENT OCCUR ALONG
THE BOUNDARY BUT NOTHING AHEAD OF IT YET OTHER THAN A FEW SHOWERS.
THE HRRR BRINGS THE ACTIVITY INTO NORTHERN PORTIONS OF THE
MIDSOUTH THIS EVENING AND THEN DISSIPATES IT BY MIDNIGHT. IN
ADDITION...THE GFS AND ECMWF SHOWED LITTLE ACTIVITY OCCURRING THIS
EVENING. IN FACT...THE ECMWF SHOWED LITTLE ACTIVITY THE ENTIRE
NIGHT. HOWEVER...THE GFS AND THE NAM BOTH SHOW REDEVELOPMENT OF
SHOWERS AFTER MIDNIGHT...POSSIBLY DUE TO A WEAK LOW LEVEL JET.
WITH SUCH A WIDE RANGE OF SCENARIOS...HAVE KEPT 40 POPS ACROSS
FROM THE TENNESSEE/MISSISSIPPI LINE NORTHWARD MAINLY DUE TO THE
CONVECTION YOU SEE BEGINNING TO DEVELOP ALONG THE OLD OUTFLOW
BOUNDARY. THINK THIS CONVECTION WILL PUSH DOWN INTO NORTHEAST
ARKANSAS...THE MISSOURI BOOTHEEL...AND NORTHWEST TENNESSEE. MAY
ALSO SEE A FEW MORE POP UP DIURNAL THUNDERSTORMS ACROSS NORTH MISSISSIPPI. DON/T
KNOW IF ANY STORM WILL BE SEVERE BUT WILL KEEP THE STRONG TO
SEVERE WORDING IN THE HWO FOR NOW. LOWS WILL BE IN THE LOWER TO
MID 70S.
MONDAY...A STRONGER SHORTWAVE WILL MOVE INTO THE REGION AS A COLD
FRONT SLIDES SOUTH INTO THE CWA. THE COMBINATION OF THE TWO SHOULD
PRODUCE NUMEROUS SHOWERS AND THUNDERSTORMS ACROSS THE CWA. CLOUD
COVER MAY AFFECT INSTABILITY LIKE IT DID TODAY BUT CAN/T RULE OUT
A FEW STORMS BECOMING STRONG TO SEVERE. ISOLATED HEAVY RAINFALL
UNDERNEATH SLOW MOVING STORMS MAY BE A BIGGEST ISSUE WITH ANY
THUNDERSTORMS THAT OCCUR TOMORROW. THE ACTIVITY WILL CONTINUE INTO
MONDAY NIGHT AND TUESDAY AS THE COLD FRONT SLIDES SOUTHWARD. HIGHS
ON MONDAY AND TUESDAY WILL BE IN THE 80S DUE TO THE CLOUD COVER
AND AMOUNT OF CONVECTION AROUND.
TUESDAY NIGHT INTO WEDNESDAY....THE GFS SLIDES THE FRONT SOUTH OF THE
CWA WHILE THE ECMWF CONTINUES TO HOLD THE FRONT UP OVER NORTH
MISSISSIPPI. BOTH THE GFS/ECMWF ARE CONSISTENT WITH THEIR
SOLUTIONS AND ITS REALLY ANYBODY/S GUESS WHICH IS CORRECT. FOR NOW
WILL CONTINUE WITH CURRENT FORECAST WHICH LEANS TOWARD THE GFS.
THURSDAY AND FRIDAY...UPPER RIDGE BEGINS TO START MOVING BACK INTO
THE AREA FROM THE WEST. SOME DIURNAL CONVECTION COULD OCCUR ON
THURSDAY. OTHERWISE...WARMER TEMPERATURES WILL RETURN WITH HIGHS
IN THE UPPER 80S TO LOWER 90S.
NEXT WEEKEND...HOT AND DRY CONDITIONS ARE EXPECTED AS THE UPPER
RIDGE WILL BE CENTERED OVER THE MIDSOUTH. HIGHS WILL BE IN THE
LOWER TO MID 90S WITH LOWS IN THE 70S.
KRM
&&
.AVIATION...
18Z TAF CYCLE
VFR CONDITIONS WILL PREVAIL THROUGH THIS TAF PERIOD. TIMING OF
TSRAS CONTINUES TO BE THE MAIN ISSUE. SURFACE HEATING COMBINED
WITH A WEAK DISTURBANCE MOVING THROUGH THIS AFTERNOON AND EARLY
EVENING WILL RESULT IN ISOLD/SCT COVERAGE SO VCTS LOOKS GOOD FROM
16/21Z-17/01Z. OVERNIGHT IS A QUESTION MARK. MODELS DIFFER ON
DEVELOPMENT LATER TONIGHT BUT SINCE THE NEXT DISTURBANCE MOVES IN
LATER ON MONDAY DECIDED TO JUST GO WITH VCSH OVERNIGHT AND
INTRODUCE A VCTS BY 17/15Z. TSRA COVERAGE WILL INCREASE AFTER THE
END OF THIS FORECAST PERIOD. WINDS WILL BE LIGHT FROM THE S/SW.
SJM
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 75 86 71 86 / 40 70 80 40
MKL 71 85 69 85 / 40 70 80 30
JBR 72 85 69 87 / 40 70 40 10
TUP 71 88 72 84 / 30 70 70 60
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
251 PM CDT SUN JUN 16 2013
.DISCUSSION...
A LESS ACTIVE AFTERNOON TODAY VERSUS THIS TIME YESTERDAY WITH THE
OLD UPPER TROUGH NOW LONG GONE AND AN UPPER RIDGE THAT HAS EXPANDED
WESTWARD ACROSS SOUTH/CENTRAL TX. THOUGH A ROGUE ISOLATED STRONG
STORM IS POSSIBLE NORTH OF I-20 THIS AFTERNOON...BETTER CHANCES
WILL LIKELY COME LATER TONIGHT. A SHORTWAVE OVER THE OK/TX
PANHANDLES WILL MOVE ESE TOWARD THE RED RIVER VALLEY AFTER MIDNIGHT.
A FEW STORMS WERE ALREADY POPPING ACROSS CENTRAL AND NORTHERN OK.
HIGH RESOLUTION HRRR/ARW-EAST/TEXAS TECH WRF MODELS ALL SHOW
CURRENT ISOLATED STORMS OVER NW OK INCREASING IN COVERAGE IN A
WEST-EAST LINE THIS EVENING...THEN DIVING SOUTHEAST TOWARD THE RED
RIVER LATE TONIGHT. TIMING THE LINEAR MCS TONIGHT IS SOMEWHAT
PROBLEMATIC HOWEVER AS THE HRRR IS MUCH FASTER THAN THE OTHER TWO
MODELS IN BRINGING ACTIVITY INTO THE RED RIVER VALLEY. CONSIDERING
WHERE THIS ACTIVITY IS FORMING AT THE MOMENT...WILL GO WITH THE
SLOWER TIMING MOSTLY BETWEEN MIDNIGHT AND SUNRISE MONDAY MORNING.
POPS WILL VARY FROM 50 PERCENT ACROSS THE IMMEDIATE RED RIVER AREA
TO AROUND 20 PERCENT ACROSS THE I-20 CORRIDOR. THE LINEAR MCS
SHOULD WEAKEN WITH THE VEERING/WEAKENING OF A 30-35KT NOCTURNAL
LLJ NEAR SUNRISE MONDAY MORNING.
THE FORECAST FOR LATER MONDAY AND THROUGH EARLY WEDNESDAY BECOMES A
BIT MORE DIFFICULT DUE TO THE UPPER RIDGE ANCHORED OVER SOUTH AND
CENTRAL TX AND WHERE ANY OUTFLOW BOUNDARIES SET UP ACROSS THE
NORTH. HAVE LINGERED BEST CHANCES AFTER SUNRISE MONDAY ACROSS THE
NORTHEAST COUNTIES WITH THE WEAKENING COMPLEX AND A SHORTWAVE
PASSING SOUTHEAST OVER ARKANSAS. LOW CHANCES LOOK PRUDENT FOR THE
AFTERNOON HOURS NEAR ANY OUTFLOWS ACROSS THE NORTHERN HALF OF THE
CWA. BY MONDAY NIGHT...ANOTHER SHORTWAVE DISTURBANCE MOVES EAST
FROM WEST TX AND WILL CARRY HIGHER CHANCES ACROSS THE WESTERN
COUNTIES BY MONDAY EVENING. THIS SYSTEM SHOULD WEAKEN AS IT HITS
THE RIDGE OVERNIGHT AND INTO TUESDAY MORNING. ON MORE SHORTWAVE
WILL TRANSITION SOUTHEAST OVER THE TOP OF THE UPPER RIDGE AND
TOWARD OUR OLD OUTFLOW BOUNDARY OVER THE NORTHERN COUNTIES WITH
ISOLATED TO SCATTERED STORMS FOR THE PM HOURS ONCE AGAIN. FEEL THE
UPPER RIDGE WILL KEEP AREAS FROM WACO AND ATHENS SOUTHWARD MAINLY
CAPPED AND DRY...THOUGH A ROGUE SHOWER CANNOT BE COMPLETELY RULED
OUT OVER OUR CENTRAL TX COUNTIES.
THE UPPER RIDGE EXPANDS NORTHWARD OVER NORTH TEXAS WEDNESDAY AS AN
UPPER LOW AND ASSOCIATED LONGWAVE TROUGH DEEPEN ACROSS THE WESTERN
U.S. HAVE LINGERED LOW RAIN CHANCES ACROSS THE FAR NORTHEAST CWA
WHERE SOME WEAKNESS ALOFT WILL REMAIN...BUT CONFIDENCE WILL BE
WANING BY THEN ON RAIN CHANCES. SUBSIDENCE AND DRY/HOT WEATHER
TAKE HOLD THE LATTER HALF OF THE WEEK INTO NEXT WEEKEND WITH RAIN
CHANCES NEAR ZERO. HIGHS WILL RISE INTO THE UPPER 90S AND 100 BY
FRIDAY AND SATURDAY...ESPECIALLY ACROSS THE WESTERN COUNTIES BY
NEXT WEEKEND.
05/
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 77 93 75 89 75 / 20 20 30 30 20
WACO, TX 75 95 75 92 75 / 5 0 20 10 10
PARIS, TX 74 90 72 87 71 / 50 50 20 40 40
DENTON, TX 76 91 73 88 73 / 30 30 30 40 30
MCKINNEY, TX 75 92 72 88 72 / 30 30 20 40 30
DALLAS, TX 77 94 75 89 76 / 20 20 20 30 20
TERRELL, TX 75 93 74 89 73 / 20 20 20 30 20
CORSICANA, TX 75 95 74 91 74 / 5 5 20 10 10
TEMPLE, TX 75 96 73 93 73 / 5 0 10 10 10
MINERAL WELLS, TX 75 93 73 89 71 / 30 20 40 30 20
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
05/
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1207 PM CDT SUN JUN 16 2013
.AVIATION...
CAVOK TAFS NOW NOT SO CERTAIN. HIGH RESOLUTION MODELS ARE HINTING
THAT CONVECTION ORIGINATING IN THE TX PANHANDLE THIS EVENING MAY
FORM A MESOSCALE CONVECTIVE SYSTEM THAT MIGHT MOVE TOWARDS THE
METROPLEX OVERNIGHT. HRRR FORECASTS A MIDNIGHT ARRIVAL. TTU WRF
HAS NOT RUN THROUGH THE OVERNIGHT HOURS YET...BUT HINTS AT AN
ARRIVAL CLOSER TO SUNRISE. WILL NOT ADD ANY TSRA TO THIS TAF BUT
WILL CLOSELY MONITOR GUIDANCE TO SEE IF MORE MODELS PRODUCE THIS
MCS. TSRA WILL THEN HAVE TO BE ADDED TO OVERNIGHT FORECAST.
AT WACO...INCREASING SOUTHEAST FLOW OVERNIGHT WILL LIKELY BRING
MORNING STRATUS...AND WILL INDICATE MVFR CEILINGS BEFORE SUNRISE.
84
&&
.UPDATE...
WEAK FLOW ALOFT CONTINUES ACROSS NORTH TEXAS THIS MORNING WITH
UPPER HIGH EXPANDING WESTWARD ACROSS SOUTH TEXAS. BEST MOISTURE
PER GOES SATELLITE PWAT IMAGERY IS ACROSS NORTHERN/WESTERN PARTS
OF THE AREA. ACCAS SEEN OUTSIDE INDICATE SOME INSTABILITY ALOFT
AND A FEW SHOWERS HAVE DEVELOPED ACROSS THE WESTERN COUNTIES. THE
HIGH-RES HRRR/RAP AND TECH WRF TO A LESSER EXTENT ARE THE ONLY
MODELS CLOSE TO ANY REALITY IN THIS WEAK FLOW SITUATION TODAY.
WILL ADJUST POPS FOR LOW CHANCES ACROSS MAINLY THESE NORTHERN AND
WESTERN COUNTIES TODAY. WILL CONTINUE SLIGHTLY HIGHER CHANCES
ACROSS OUR FAR NORTHEAST COUNTIES LATE TODAY THROUGH SUNSET ONCE
AGAIN...AS SHORTWAVE MOVING FROM THE OK/TX PANHANDLES TRANSVERSES
EAST WITH TIME. SOME RESIDUAL OUTFLOW BOUNDARIES MAY ALSO PLAY A
ROLE ACROSS THE NORTHEAST. SIMILAR TO YESTERDAY...ENOUGH INSTABILITY
WILL EXIST FOR A STRONG STORM OR TWO WITH FREQUENT LIGHTNING...GUSTY
WINDS...AND LOCALIZED BRIEF HEAVY DOWNPOURS. FOR THOSE PLANNING
OUTDOOR EVENTS FATHERS DAY WILL NEED TO PAY ATTENTION THIS AFTERNOON
ALONG AND NORTH OF I-20/I-30.
DID LOWER HIGHS SOME OUT WEST FROM THE PREVIOUS FORECAST...WITH
CURRENT MID LEVEL CLOUD DECK AND ISOLATED SHOWERS EXPECTED INTO
THE EARLY AFTERNOON HOURS.
05/
&&
.PREV DISCUSSION... /ISSUED 329 AM CDT SUN JUN 16 2013/
THE FORECAST ESSENTIALLY BREAKS DOWN INTO TWO PARTS...THE SEMI-
WET PERIOD FOR THE NEXT FEW DAYS...AND THE DRY AND WARM/HOT
PERIOD FOR LATE WEEK INTO THE WEEKEND.
ALTHOUGH THE MAIN TROUGH IS MOVING EASTWARD THIS MORNING...A WEAK
DISTURBANCE MAY STILL BRING ANOTHER CHANCE OF SHOWERS
THUNDERSTORMS TODAY. THE HIGH RESOLUTION RAPID REFRESH IS THE
MOST AGGRESSIVE IN GENERATING ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS THROUGH THIS AFTERNOON. THE NAM AND TEXAS TECH WRF
ON THE OTHER HAND SHOW LITTLE IF ANY PRECIPITATION TODAY. IT
APPEARS THAT THE HRRR MAY BE TOO AGGRESSIVE...SO HAVE JUST GONE
WITH 20 PERCENT POPS ACROSS ALL BUT THE EXTREME WESTERN ZONES FOR
TODAY WHERE HAVE PLACED 10 PERCENT POPS AND THE NORTHEAST WHERE
THERE ARE 30 PERCENT POPS FOR THIS AFTERNOON. THIS SEEMS TO BE
CLOSER TO WHAT THE GFS/ECMWF/CANADIAN ARE INDICATING. AS A
STRONGER SHORTWAVE SLIDES ACROSS THE CENTRAL PLAINS
TONIGHT...MOST OF THE RAIN WILL BE TO THE NORTH OF THE FORECAST
AREA BUT HAVE KEPT SOME 20 PERCENT POPS ALONG AND NORTH OF A
GRAHAM TO SULPHUR SPRINGS LINE. THERE IS PRETTY GOOD AGREEMENT
BETWEEN THE GFS...ECWMF...CANADIAN AND TO A LESSER DEGREE THE
NAM...THAT THAT A COUPLE OF SHORTWAVES MOVING ACROSS CENTRAL AND
SOUTHERN PLAINS WILL DRIVE A COLD FRONT INTO NORTH TEXAS MONDAY
NIGHT...AND STALL IT NEAR OR SOUTH OF THE I-20 CORRIDOR TUESDAY.
THE FRONT WILL THEN LIFT BACK TO THE NORTH ON WEDNESDAY. THE BEST
RAIN CHANCES WILL BE NEAR AND NORTH OF THIS FRONT...SO HAVE
PLACED 30-40 PERCENT POPS ACROSS THE NORTH...WITH ONLY 20 PERCENT
ACROSS THE SOUTH.
RAIN CHANCES WILL END LATE WEDNESDAY AS AN UPPER RIDGE STARTS TO
BUILD INTO THE SOUTHERN PLAINS IN THE WAKE OF THE UPPER TROUGH
MOVING EASTWARD AND AN INTENSE UPPER LEVEL STORM MOVING INTO THE
PACIFIC NORTHWEST. THE RIDGE WILL TAKE RESIDENCE OVER THE SOUTHERN
PLAINS LATE WEEK INTO THE WEEKEND...BRINGING ABOVE NORMAL HIGH
TEMPERATURES WITH NO SIGNIFICANT CHANCE OF RAIN.
58
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 94 76 93 73 87 / 20 10 20 40 30
WACO, TX 96 75 95 74 92 / 10 10 10 20 20
PARIS, TX 92 73 90 71 85 / 30 20 30 40 30
DENTON, TX 92 75 91 72 86 / 20 20 20 40 30
MCKINNEY, TX 92 74 92 71 86 / 20 20 20 40 30
DALLAS, TX 95 76 94 74 89 / 20 10 20 40 30
TERRELL, TX 94 74 93 73 89 / 20 10 20 30 30
CORSICANA, TX 95 74 94 73 91 / 10 10 10 20 20
TEMPLE, TX 96 74 93 72 93 / 10 10 10 20 20
MINERAL WELLS, TX 93 74 93 72 87 / 20 10 20 40 30
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1218 PM CDT SUN JUN 16 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 307 AM CDT SUN JUN 16 2013
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED AN UPPER LOW OFF THE PACIFIC NORTHWEST COAST...AND NEARLY
ZONAL FLOW ACROSS MUCH OF THE NORTHERN U.S.. WITHIN THE ZONAL
FLOW...A COLLECTION OF SHORTWAVES...SOME CONVECTIVELY INDUCED...
EXTENDED FROM LOWER MICHIGAN INTO ARKANSAS. THESE SHORTWAVES HELPED
PRODUCE SOME OF THE CONVECTION YESTERDAY AFTERNOON AND EVENING. DRY
AIR HAS ADVECTED INTO THE FORECAST AREA BEHIND THE SHORTWAVES...
NOTED ON WATER VAPOR AS WELL AS THE 00Z MPX SOUNDING WHERE THE
PRECIPITABLE WATER HAS FALLEN TO 0.94 INCHES. FARTHER WEST...THE AIR
GETS EVEN DRIER...WITH THE 00Z ABR SOUNDING AT 0.34 INCHES FOR
PRECIPITABLE WATER. THE DRY AIR HAS EFFECTIVELY CLEARED MUCH OF THE
SKIES OUT. LIGHT WINDS...THE DRY AIR ALOFT AND PRECIPITATION LAST
EVENING HAS LED TO SOME FOG DEVELOPMENT... ESPECIALLY NORTH OF THE
I-94 CORRIDOR AS WELL AS IN THE MS RIVER VALLEY NORTH OF PRAIRIE DU
CHIEN. 850MB TEMPS DID NOT DROP MUCH WITH THE SHORTWAVE PASSAGE...
WITH READINGS GENERALLY 14-17C FROM THE DAKOTAS EAST INTO WISCONSIN.
MEANWHILE...TO THE NORTHWEST...AN UPPER LOW WAS SITTING OVER
SOUTHEAST SASKATCHEWAN. SOME CONVECTION FORMED AHEAD OF THE UPPER
LOW ALONG THE CANADIAN BORDER WITH NORTH DAKOTA AND MN DURING THE
DAYTIME HOURS YESTERDAY. THIS HAS SINCE MOSTLY DISSIPATED.
MAIN FOCUS IS ON THE UPPER LOW IN SOUTHEAST SASKATCHEWAN. MODELS
CONTINUE TO SHOW THE LOW DROPPING SOUTHEASTWARD AS IT BEGINS TO GET
CAUGHT UP IN THE CIRCULATION AROUND TROUGHING IN EASTERN CANADA. AT
THE SAME TIME...THE UPPER LOW IS PROGGED TO SHEAR OUT INTO A
SHORTWAVE. THERE ARE MODEL DIFFERENCES IN HOW FAR SOUTH THE
SHORTWAVE GETS TO AT 12Z MONDAY...RANGING FROM NEAR MINNEAPOLIS FROM
THE 16.00Z GFS TO NEAR BRAINERD MN FROM THE 16.00Z
NAM/UKMET/CANADIAN. THIS DIFFERENCE HAS IMPLICATIONS ON TIMING OF
POTENTIAL PRECIPITATION LATER TONIGHT.
TODAY CONTINUES TO LOOK QUIET AS WEST-NORTHWEST FLOW AHEAD OF THE
APPROACHING UPPER LOW/SHORTWAVE HELPS TO BRING THAT DRIER AIR IN
SEEN ON THE 00Z ABR SOUNDING. ANY CONVECTIVE ACTIVITY AHEAD OF THE
UPPER LOW/SHORTWAVE LIKE SEEN YESTERDAY AFTERNOON AND EVENING WILL
STAY NORTH AND WEST OF THE AREA. WE SHOULD SEE PLENTY OF
SUNSHINE...EASILY ALLOWING MIXING TO 850MB WHERE TEMPS OF 13-14C
WILL ALLOW FOR HIGHS IN THE LOW TO MID 80S. EXPECT ANY FOG THIS
MORNING TO QUICKLY DISSIPATE...LIKELY BY 9 AM OR EVEN EARLIER
GIVEN THE EARLY SUNRISE.
FOR TONIGHT...GOOD AGREEMENT EXISTS AMONGST MODELS THAT A SURGE OF
SOMEWHAT HIGHER PRECIPITABLE WATER WILL ADVECT INTO THE FORECAST
AREA AS THE UPPER LOW/SHORTWAVE DROPS INTO MN. VALUES CLIMB UP TO
AROUND 1 INCH. AT THE SAME TIME...THERE IS A DEFINITE SURGE OF 850MB
MOISTURE TRANSPORT TO HELP SUPPORT PRECIPITATION. BETWEEN THE
MOISTURE ADVECTION AND DPVA AHEAD OF THE UPPER LOW/SHORTWAVE...SOME
SCATTERED SHOWER AND THUNDERSTORM ACTIVITY SHOULD BE PRESENT AND
PERSIST THROUGH THE NIGHT. 16.00Z NAM/GFS/CANADIAN ALL INDICATE
PRECIPITATION...BUT IT IS JUST A MATTER HOW FAR SOUTH IT GETS WHICH
GOES BACK TO THE MODEL TIMING DIFFERENCES MENTIONED EARLIER. HAVE
FOLLOWED THE MAJORITY SOLUTION OF A SLOWER APPROACH...WHICH RESULTS
IN THE HIGHEST CHANCES OF 30-40 OVER THE NORTHERN 1/3 OF THE
FORECAST AREA. DID EXTEND A 20 PERCENT CHANCE DOWN INTO SOUTHEAST MN
IN THE EVENT THE FASTER 16.00Z GFS COMES TRUE. MOST OF THESE CHANCES
ARE ALSO AFTER MIDNIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 307 AM CDT SUN JUN 16 2013
MONDAY INTO MONDAY NIGHT...SHORTWAVE LURKING UP TO OUR NORTHWEST AT
12Z MONDAY IS WELL AGREED UPON TO REACH THE I-90 CORRIDOR IN THE
FORECAST AREA AT 00Z TUESDAY...DESPITE THE MODEL DIFFERENCES ON
TIMING BEFORE THAT. ACCOMPANYING THE SHORTWAVE WILL BE A COLD FRONT
WHICH SHOULD GRADUALLY MAKE ITS WAY SOUTH THROUGH THE AREA DURING
THE DAY. ANTICIPATING SCATTERED SHOWER/THUNDERSTORM ACTIVITY THAT
WAS DROPPING INTO NORTHERN PORTIONS OF THE AREA LATE SUNDAY NIGHT TO
CONTINUE DROPPING SOUTH AND POSSIBLY WEAKEN AS THE 850MB MOISTURE
TRANSPORT FALLS APART. AS INSTABILITY BUILDS DURING THE DAY...
THUNDERSTORMS MAY FORM BOTH ALONG THE COLD FRONT IN THE SOUTHERN
PORTION OF THE FORECAST AREA...AS WELL AS UNDER THE COLDER CORE OF
AIR ASSOCIATED WITH THE SHORTWAVE. THUS...IT APPEARS MONDAY WILL BE
AN OFF AND ON PRECIP DAY AT THIS TIME. 0-6KM SHEAR IS NOT THE
GREATEST FOR THINKING SEVERE WEATHER...GENERALLY 30-35 KT OVER THE
SOUTHERN TWO THIRDS OF THE AREA IN THE AFTERNOON. THIS WOULD SUGGEST
MOST OF THE CONVECTION TAKING ON A MULTI-CELLULAR APPEARANCE.
HOWEVER...FREEZING LEVELS DO LOWER AT 21Z TO 9000 FT OVER THE NORTH
TO 10500-11000 FT AGL IN THE SOUTH...SO HAIL IS A DEFINITE
POSSIBILITY FROM THE AFTERNOON STORMS. ANY CONVECTION FROM MONDAY
AFTERNOON SHOULD DIMINISH QUICKLY DURING THE EVENING WITH LOSS OF
DAYTIME HEATING...THE SHORTWAVE HEADING INTO NORTHERN ILLINOIS AND
HIGH PRESSURE BUILDING IN FROM THE NORTH.
TUESDAY INTO TUESDAY NIGHT...WHAT LOOKED TO BE A QUIET PERIOD FOR
MANY DAYS IS BECOMING A LITTLE MORE PROBLEMATIC. THE 15.00Z ECMWF
SHOWED A FAIRLY POTENT SHORTWAVE DROPPING THROUGH WESTERN PORTIONS
OF THE FORECAST AREA DURING THE DAYTIME HOURS ON TUESDAY. SO
ALTHOUGH A RIDGE OF HIGH PRESSURE IS IN PLACE AT THE SURFACE...THE
COLDER AIR ALOFT ACCOMPANYING THE SHORTWAVE RESULTED IN
PRECIPITATION. TODAY...THE 16.00Z NAM/UKMET/GFS/ECMWF/CANADIAN
CONTINUE TO SHOW THIS SHORTWAVE BUT ITS TRACK IS ALL OVER THE PLACE.
THE NAM/UKMET/ECMWF DROP IT SOUTHEAST THROUGH CENTRAL WI WHILE THE
GFS AND 15.12Z ECMWF BRING IT THROUGH SOUTHEAST MN AND NORTHEAST
IA. THE CANADIAN LIES BETWEEN THE TWO. FOR REFERENCE...THE SHORTWAVE
RIGHT NOW SITS ALONG THE SOUTHERN ALBERTA/SASKATCHEWAN BORDER.
DESPITE THE TRACK DIFFERENCES...LIGHT MODEL QPF IS MOSTLY CENTERED
WEST OF THE MS RIVER DURING THE TUESDAY DAYTIME HOURS. THIS AREA
APPEARS TO BE THE BEST JUXTAPOSITION OF DIURNAL HEATING/LOW LEVEL
MOISTENING AND THE COOL AIR ALOFT WITH THE SHORTWAVE. DESPITE SEEING
THE LIGHT QPF SIGNAL...HAVE CONTINUED TO STAY WITH THE DRY FORECAST
THINKING THAT THE MODELS MAY BE OVERDOING LOW LEVEL DEWPOINTS. A
NORTHEAST SURFACE FLOW OUT OF HIGH PRESSURE IN UPPER MI SHOULD
PROVIDE A DRY FLOW OF AIR. AFTER THE SHORTWAVE PASSES...A DRY AND
COOL NIGHT IS IN STORE FOR TUESDAY NIGHT AS HIGH PRESSURE SETTLES
IN.
WEDNESDAY THROUGH SATURDAY NIGHT...
THE UPPER LOW CURRENTLY SITTING OFF THE PACIFIC NORTHWEST COAST IS
FORECAST TO SLOWLY PUSH EAST THE NEXT FEW DAYS...ENCOMPASSING MUCH
OF THE PACIFIC NORTHWEST ON WEDNESDAY. DOWNSTREAM RIDGING SHOULD BE
IN PLACE FROM THE NORTHWEST TERRITORIES DOWN INTO THE SOUTHERN
PLAINS...PLACING THE FORECAST AREA IN SUBSIDENCE. MODELS REMAIN IN
GOOD AGREEMENT KEEPING THE AREA DRY WEDNESDAY AND WEDNESDAY
NIGHT...STAYING IN SUBSIDENCE AND DRY AIR WITH HIGH PRESSURE NEARBY
AT THE SURFACE. THE PATTERN THEN BEGINS TO CHANGE ACCORDING TO THE
16.00Z ECMWF/CANADIAN/GFS AND GFS ENSEMBLES...SUGGESTING THE
TROUGHING THAT HAS BEEN PERSISTENT OVER SOUTHEAST CANADA BEGINS TO
LIFT OUT. ADDITIONALLY...THE UPPER LOW IN THE PACIFIC NORTHWEST
SLOWLY EJECTS EAST-NORTHEAST. ALL THESE CHANGES OCCURRING TO THE
UPPER LEVEL PATTERN SETS UP WARM ADVECTION AND A DECENT RETURN OF
GULF OF MEXICO MOISTURE BACK TOWARDS THE UPPER MISSISSIPPI RIVER
VALLEY REGION. AS A RESULT...PRECIPITATION CHANCES BEGIN TO SLOWLY
INCREASE...AS EARLY AS THURSDAY. MUCH OF THE FORECAST FROM THURSDAY
NIGHT THROUGH SATURDAY NIGHT IS BROAD BRUSHED WITH 30-40 PERCENT
CHANCES AS THE FORECAST PATTERN LENDS ITSELF TO MULTIPLE ROUNDS OF
CONVECTION. WILL LIKELY HAVE TO WAIT MANY DAYS TO NAIL DOWN ANY
TIMING OR LOCATION OF THIS CONVECTION. CERTAINLY POTENTIAL HERE FOR
HEAVY RAIN...AND POSSIBLY SEVERE WEATHER TOO...BUT THOSE DETAILS ARE
TOO EARLY TO HASH OUT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1218 PM CDT SUN JUN 16 2013
HIGH PRESSURE WILL PROVIDE VFR CONDITIONS AT THE TAF SITES THROUGH
THIS EVENING. FEW TO SCATTERED CUMULUS HAVE DEVELOP AND WILL
PERSIST THROUGH THE AFTERNOON WITH CLOUD BASES OF 4500 TO 5000 FT.
CIRRUS WILL MOVE DURING THE MID AFTERNOON HOURS...FROM ONGOING
SHOWERS/STORMS OVER PORTIONS OF WESTERN SOUTH DAKOTA. A COLD FRONT
AND UPPER TROUGH WILL PUSH SOUTH OUT OF SOUTHERN MANITOBA/ONTARIO
LATE TONIGHT INTO MONDAY...POSSIBLY GENERATING A FEW SHOWERS AND
THUNDERSTORMS MAINLY ALONG AND NORTH OF INTERSTATE 90. THE HIGHER
CHANCES FOR SHOWERS AND THUNDERSTORMS WILL ARRIVE MONDAY AFTERNOON
AS THE UPPER TROUGH MOVES SOUTH INTO THE UPPER MISSISSIPPI RIVER
VALLEY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE.......AJ/RRS
SHORT TERM...AJ
LONG TERM... AJ
AVIATION...WETENKAMP